Pawel R Kiela

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Scholarly Contributions

Chapters

• Kiela, P. R., Xu, H., & Ghishan, F. K. (2021). Na+/H+ Exchangers in Epithelia. In Studies of Epithelial Transporters and Ion Channels: Ion Channels and Transporters of Epithelia in Health and Disease(pp 125-209). Springer.
• Kiela, P. R., & Ghishan, F. K. (2018). Molecular Mechanisms of Intestinal Transport of Calcium, Phosphate, and Magnesium. In Physiology of the Gastrointestinal Tract. Elsevier.
• Kiela, P. R., & Ghishan, F. K. (2018). Na+/H+ Exchange in Mammalian Digestive Tract. In Physiology of the Gastrointestinal Tract.
• Kiela, P. R., & Ghishan, F. K. (2016). Physiology of Intestinal Absorption and Secretion. In Diagnosis & Management of Malabsorption.
• Kiela, P. R., & Ghishan, F. K. (2006). CHAPTER 73 – Na+-H+ Exchange in Mammalian Digestive Tract. In Physiology of the Gastrointestinal Tract. doi:10.1016/B978-012088394-3/50076-3

Journals/Publications

• Balasubramanian, I., Bandyopadhyay, S., Flores, J., Bianchi-Smak, J., Lin, X., Liu, H., Sun, S., Golovchenko, N. B., Liu, Y., Wang, D., Patel, R., Joseph, I., Suntornsaratoon, P., Vargas, J., Green, P. H., Bhagat, G., Lagana, S. M., Ying, W., Zhang, Y., , Wang, Z., et al. (2023). Infection and inflammation stimulate expansion of a CD74 Paneth cell subset to regulate disease progression. The EMBO journal, 42(21), e113975.
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  Paneth cells (PCs), a specialized secretory cell type in the small intestine, are increasingly recognized as having an essential role in host responses to microbiome and environmental stresses. Whether and how commensal and pathogenic microbes modify PC composition to modulate inflammation remain unclear. Using newly developed PC-reporter mice under conventional and gnotobiotic conditions, we determined PC transcriptomic heterogeneity in response to commensal and invasive microbes at single cell level. Infection expands the pool of CD74 PCs, whose number correlates with auto or allogeneic inflammatory disease progressions in mice. Similar correlation was found in human inflammatory disease tissues. Infection-stimulated cytokines increase production of reactive oxygen species (ROS) and expression of a PC-specific mucosal pentraxin (Mptx2) in activated PCs. A PC-specific ablation of MyD88 reduced CD74 PC population, thus ameliorating pathogen-induced systemic disease. A similar phenotype was also observed in mice lacking Mptx2. Thus, infection stimulates expansion of a PC subset that influences disease progression.
• Laubitz, D., Gurney, M. A., Midura-Kiela, M., Clutter, C., Besselsen, D. G., Chen, H., Ghishan, F. K., & Kiela, P. R. (2022). Decreased NHE3 expression in colon cancer is associated with DNA damage, increased inflammation and tumor growth. Scientific reports, 12(1), 14725.
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  Dysregulation of intra- and extracellular pH in cancer contributes to extracellular matrix remodeling, favors cell migration, proliferation, and metastasis. Although the primary attention has been focused on the role of the ubiquitous Na/H exchanger isoform NHE1, the role of NHE3, the predominant apical isoform in colonic surface epithelium in the pathogenesis of colon cancer has not been investigated. Here, we show that NHE3 mRNA expression is significantly reduced in colorectal cancer patients and that low NHE3 expression is associated with poorer survival. Deletion of NHE3 in Apc mice evaluated at 15 weeks of age (significant mortality was observed beyond this time) led to lower body weights, increased mucosal inflammation, increased colonic tumor numbers, evidence of enhanced DNA damage in tumor surface epithelium, and to significant alteration in the gut microbiota. In the absence of the inflammatory and microbial pressors, ca. 70% knockdown of NHE3 expression in SK-CO15 cells led to reduced intracellular pH, elevated apical pH, dramatic differences in their transcriptomic profile, increased susceptibility to DNA damage, increased proliferation, decreased apoptosis and reduced adhesion to extracellular matrix proteins. Our findings suggest that loss of NHE3 in the surface epithelium of colonic tumors has profound consequences for cancer progression and behavior.
• Mashaqi, S., Laubitz, D., Morales, E. J., De Armond, R., Alameddin, H., Ghishan, F. K., Kiela, P. R., & Parthasarathy, S. (2022). Interactive Effect of Combined Intermittent and Sustained Hypoxia and High-Fat Diet on the Colonic Mucosal Microbiome and Host Gene Expression in Mice. Nature and science of sleep, 14, 1623-1639.
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  Gut dysbiosis can cause cardiometabolic disease. Gut dysbiosis can be independently caused by high-fat diet (HFD) and intermittent hypoxia (IH; characterizing obstructive sleep apnea), but the interactive effect of combined intermittent and sustained hypoxia (IH+SH) (characterizing obesity hypoventilation syndrome) and HFD on gut dysbiosis is unclear. We aimed to investigate the interactive effect of a combination of IH and SH and HFD on proximal colonic microbiota and colonic gene expression pattern.
• Schiro, G., Liu, P., Dodson, M., Zhang, D. D., Ghishan, F. K., Barberan, A., & Kiela, P. R. (2022). Interactions between arsenic exposure, high-fat diet and NRF2 shape the complex responses in the murine gut microbiome and hepatic metabolism. Frontiers in Microbiomes. doi:https://doi.org/10.3389/frmbi.2022.1041188
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  Inorganic arsenic (iAs) exposure has been associated to various detrimental effects such as development of metabolic syndrome and type 2 diabetes via oxidative stress and induced prolonged activation of the NRF2 transcription factor. Such effects can be aggravated by poor dietary habits. The role of gut microbiota in promoting metabolic changes in response to arsenic has yet to be precisely defined. To address the complexity of the interactions between diet, NFE2L2/NRF2, and gut microbiota, we studied the chronic effects of iAs exposure in wild-type (WT) and Nrf2-/- mice fed normal (ND) vs. high-fat diet (HFD), on the gut microbial community in the context of hepatic metabolism. We demonstrate that all treatments and interactions influenced bacteria and metabolic profiles, with dietary differences causing a strong overlap of responses between the datasets. By identifying five metabolites of known microbial origin and following their fate across treatments, we provide examples on how gut microbial products can participate in the development of iAs and HFD-induced metabolic disease. Overall, our results underline the importance of the microbial community in driving gut-liver-cross talk during iAs and HFD exposure.
• Detman, A., Laubitz, D., Chojnacka, A., Kiela, P. R., Salamon, A., Barberán, A., Chen, Y., Yang, F., Błaszczyk, M. K., & Sikora, A. (2021). Dynamics of dark fermentation microbial communities in the light of lactate and butyrate production. Microbiome, 9(1), 158.
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  This study focuses on the processes occurring during the acidogenic step of anaerobic digestion, especially resulting from nutritional interactions between dark fermentation (DF) bacteria and lactic acid bacteria (LAB). Previously, we have confirmed that DF microbial communities (MCs) that fed on molasses are able to convert lactate and acetate to butyrate. The aims of the study were to recognize the biodiversity of DF-MCs able and unable to convert lactate and acetate to butyrate and to define the conditions for the transformation.
• Figliuolo da Paz, V. R., Jamwal, D. R., & Kiela, P. R. (2021). Intestinal Regulatory T Cells. Advances in experimental medicine and biology, 1278, 141-190.
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  Mucosal surfaces are distinctive sites exposed to environmental, dietary, and microbial antigens. Particularly in the gut, the host continuously actively adapts via complex interactions between the microbiota and dietary compounds and immune and other tissue cells. Regulatory T cells (Tregs) are critical for tuning the intestinal immune response to self- and non-self-antigens in the intestine. Its importance in intestinal homeostasis is illustrated by the onset of overt inflammation caused by deficiency in Treg generation, function, or stability in the gut. A substantial imbalance in Tregs has been observed in intestinal tissue during pathogenic conditions, when a tightly regulated and equilibrated system becomes dysregulated and leads to unimpeded and chronic immune responses. In this chapter, we compile and critically discuss the current knowledge on the key factors that promote Treg-mediated tolerance in the gut, such as those involved in intestinal Treg differentiation, specificity and suppressive function, and their immunophenotype during health and disease. We also discuss the current state of knowledge on Treg dysregulation in human intestine during pathological states such as inflammatory bowel disease (IBD), necrotizing enterocolitis (NEC), graft-versus-host disease (GVHD), and colorectal cancer (CRC), and how that knowledge is guiding development of Treg-targeted therapies to treat or prevent intestinal disorders.
• Laubitz, D., Typpo, K., Midura-Kiela, M., Brown, C., Barberán, A., Ghishan, F. K., & Kiela, P. R. (2021). Dynamics of Gut Microbiota Recovery after Antibiotic Exposure in Young and Old Mice (A Pilot Study). Microorganisms, 9(3).
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  Antibiotics have improved survival from previously deadly infectious diseases. Antibiotics alter the microbial composition of the gut microbiota, and these changes are associated with diminished innate immunity and decline in cognitive function in older adults. The composition of the human microbiota changes with age over the human lifespan. In this pilot study, we sought to identify if age is associated with differential recovery of the microbiota after antibiotic exposure. Using 16S rRNA gene sequencing, we compared recovery of the gut microbiota after the 10-day broad-spectrum antibiotic treatment in wild-type C57BL/six young and older mice. Immediately after antibiotic cessation, as expected, the number of ASVs, representing taxonomic richness, in both young and older mice significantly declined from the baseline. Mice were followed up to 6 months after cessation of the single 10-day antibiotic regimen. The Bray-Curtis index recovered within 20 days after antibiotic cessation in young mice, whereas in older mice the microbiota did not fully recover during the 6-months of follow-up. , , _NK4A136_group became dominant in older mice, whereas in young mice, the bacteria were more evenly distributed, with only one dominant genus of From 45 genera that became extinct after antibiotic treatment in young mice, 31 (68.9%) did not recover by the end of the study. In older mice, from 36 extinct genera, 27 (75%) did not recover. The majority of the genera that became extinct and never recovered belonged to phylum and family. In our study, age was a factor associated with the long-term recovery of the gut microbiota after the 10-day antibiotic treatment.
• Paz, V. F., Kiela, P. R., & Jamwal, D. R. (2021). Intestinal Regulatory T Cells.. Advances in Experimental Medicine and Biology, 1278, 141-190. doi:10.1007/978-981-15-6407-9_9
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  Mucosal surfaces are distinctive sites exposed to environmental, dietary, and microbial antigens. Particularly in the gut, the host continuously actively adapts via complex interactions between the microbiota and dietary compounds and immune and other tissue cells. Regulatory T cells (Tregs) are critical for tuning the intestinal immune response to self- and non-self-antigens in the intestine. Its importance in intestinal homeostasis is illustrated by the onset of overt inflammation caused by deficiency in Treg generation, function, or stability in the gut. A substantial imbalance in Tregs has been observed in intestinal tissue during pathogenic conditions, when a tightly regulated and equilibrated system becomes dysregulated and leads to unimpeded and chronic immune responses. In this chapter, we compile and critically discuss the current knowledge on the key factors that promote Treg-mediated tolerance in the gut, such as those involved in intestinal Treg differentiation, specificity and suppressive function, and their immunophenotype during health and disease. We also discuss the current state of knowledge on Treg dysregulation in human intestine during pathological states such as inflammatory bowel disease (IBD), necrotizing enterocolitis (NEC), graft-versus-host disease (GVHD), and colorectal cancer (CRC), and how that knowledge is guiding development of Treg-targeted therapies to treat or prevent intestinal disorders.
• Rivas, C. M., Schiff, H. V., Moutal, A., Khanna, R., Kiela, P. R., Price, T. J., Vagner, J., DeFea, K. A., & Boitano, S. (2022). Alternaria alternata-induced airway epithelial signaling and inflammatory responses via protease-activated receptor-2 expression.. Biophysical and Biochemical Research Communications, 591, 13-19. doi:10.1016/j.bbrc.2021.12.090
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  Inhalation of the fungus Alternaria alternata is associated with an increased risk of allergic asthma development and exacerbations. Recent work in acute exposure animal models suggests that A. alternata-induced asthma symptoms, which include inflammation, mucus overproduction and airway hyperresponsiveness, are due to A. alternata proteases that act via protease-activated receptor-2 (PAR2). However, because other active components present in A. alternata may be contributing to asthma pathophysiology through alternative signaling, the specific role PAR2 plays in asthma initiation remains undefined. Airway epithelial cells provide the first encounter with A. alternata and are thought to initiate the physiological response. To better understand the role for PAR2 airway epithelial signaling we created a PAR2-deficient human bronchial epithelial cell line (16HBEPAR-/-) from a model bronchial parental line (16HBE14o-). Comparison of in vitro physiological responses in these cell lines demonstrated a complete loss of PAR2 agonist (2at-LIGRL-NH2) response and significantly attenuated protease (trypsin and elastase) and A. alternata responses in the 16HBEPAR-/- line. Apical application of A. alternata to 16HBE14o- and 16HBEPAR2-/- grown at air-liquid interface demonstrated rapid, PAR2-dependent and independent, inflammatory cytokine, chemokine and growth factor basolateral release. In conclusion, the novel human PAR2-deficient cell line allows for direct in vitro examination of the role(s) for PAR2 in allergen challenge with polarized human airway epithelial cells.
• Typpo, K. V., Midura-kiela, M. T., Laubitz, D., Kiela, P. R., Ghishan, F. K., Brown, C., & Barberan, A. (2021). Dynamics of Gut Microbiota Recovery after Antibiotic Exposure in Young and Old Mice (A Pilot Study).. Microorganisms, 9(3), 647. doi:10.3390/microorganisms9030647
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  Antibiotics have improved survival from previously deadly infectious diseases. Antibiotics alter the microbial composition of the gut microbiota, and these changes are associated with diminished innate immunity and decline in cognitive function in older adults. The composition of the human microbiota changes with age over the human lifespan. In this pilot study, we sought to identify if age is associated with differential recovery of the microbiota after antibiotic exposure. Using 16S rRNA gene sequencing, we compared recovery of the gut microbiota after the 10-day broad-spectrum antibiotic treatment in wild-type C57BL/six young and older mice. Immediately after antibiotic cessation, as expected, the number of ASVs, representing taxonomic richness, in both young and older mice significantly declined from the baseline. Mice were followed up to 6 months after cessation of the single 10-day antibiotic regimen. The Bray-Curtis index recovered within 20 days after antibiotic cessation in young mice, whereas in older mice the microbiota did not fully recover during the 6-months of follow-up. Bifidobacterium, Dubosiella, Lachnospiraceae_NK4A136_group became dominant in older mice, whereas in young mice, the bacteria were more evenly distributed, with only one dominant genus of Anaeroplasma. From 45 genera that became extinct after antibiotic treatment in young mice, 31 (68.9%) did not recover by the end of the study. In older mice, from 36 extinct genera, 27 (75%) did not recover. The majority of the genera that became extinct and never recovered belonged to Firmicutes phylum and Clostridiales family. In our study, age was a factor associated with the long-term recovery of the gut microbiota after the 10-day antibiotic treatment.
• Wu, M. H., Padilla-Rodriguez, M., Blum, I., Camenisch, A., Figliuolo da Paz, V., Ollerton, M., Muller, J., Momtaz, S., Mitchell, S. A., Kiela, P., Thorne, C., Wilson, J. M., & Cox, C. M. (2021). Proliferation in the developing intestine is regulated by the endosomal protein Endotubin. Developmental biology, 480, 50-61.
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  During postnatal intestinal development, the intestinal epithelium is highly proliferative, and this proliferation is regulated by signaling in the intervillous and crypt regions. This signaling is primarily mediated by Wnt, and requires membrane trafficking. However, the mechanisms by which membrane trafficking regulates signaling during this developmental phase are largely unknown. Endotubin (EDTB, MAMDC4) is an endosomal protein that is highly expressed in the apical endocytic complex (AEC) of villus enterocytes during fetal and postnatal development, and knockout of EDTB results in defective formation of the AEC and giant lysosome. Further, knockout of EDTB in cell lines results in decreased proliferation. However, the role of EDTB in proliferation during the development of the intestine is unknown. Using Villin-CreERT2 in EDTB mice, we deleted EDTB in the intestine in the early postnatal period, or in enteroids in vitro after isolation of intervillous cells. Loss of EDTB results in decreased proliferation in the developing intestinal epithelium and decreased ability to form enteroids. EDTB is present in cells that contain the stem cell markers LGR5 and OLFM4, indicating that it is expressed in the proliferative compartment. Further, using immunoblot analysis and TCF/LEF-GFP mice as a reporter of Wnt activity, we find that knockout of EDTB results in decreased Wnt signaling. Our results show that EDTB is essential for normal proliferation during the early stages of intestinal development and suggest that this effect is through modulation of Wnt signaling.
• Zhang, Q., Zhang, Q., Zhang, D. D., Zhang, D. D., White, E., White, E., Wei, Y., Wei, Y., Shakya, A., Shakya, A., Schmidlin, C. J., Schmidlin, C. J., Ooi, A., Ooi, A., Liu, P., Liu, P., Li, H., Li, H., Kiela, P. R., , Kiela, P. R., et al. (2021). Non-canonical NRF2 activation promotes a pro-diabetic shift in hepatic glucose metabolism.. Molecular metabolism, 51, 101243. doi:10.1016/j.molmet.2021.101243
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  NRF2, a transcription factor that regulates cellular redox and metabolic homeostasis, plays a dual role in human disease. While it is well known that canonical intermittent NRF2 activation protects against diabetes-induced tissue damage, little is known regarding the effects of prolonged non-canonical NRF2 activation in diabetes. The goal of this study was to determine the role and mechanisms of prolonged NRF2 activation in arsenic diabetogenicity..To test this, we utilized an integrated transcriptomic and metabolomic approach to assess diabetogenic changes in the livers of wild type, Nrf2-/-, p62-/-, or Nrf2-/-; p62-/- mice exposed to arsenic in the drinking water for 20 weeks..In contrast to canonical oxidative/electrophilic activation, prolonged non-canonical NRF2 activation via p62-mediated sequestration of KEAP1 increases carbohydrate flux through the polyol pathway, resulting in a pro-diabetic shift in glucose homeostasis. This p62- and NRF2-dependent increase in liver fructose metabolism and gluconeogenesis occurs through the upregulation of four novel NRF2 target genes, ketohexokinase (Khk), sorbitol dehydrogenase (Sord), triokinase/FMN cyclase (Tkfc), and hepatocyte nuclear factor 4 (Hnf4A)..We demonstrate that NRF2 and p62 are essential for arsenic-mediated insulin resistance and glucose intolerance, revealing a pro-diabetic role for prolonged NRF2 activation in arsenic diabetogenesis.
• Figliuolo da Paz, V., Ghishan, F. K., & Kiela, P. R. (2020). Emerging Roles of Disabled Homolog 2 (DAB2) in Immune Regulation. Frontiers in immunology, 11, 580302.
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  Disabled-2 (DAB2) is a clathrin and cargo binding endocytic adaptor protein recognized for its multifaceted roles in signaling pathways involved in cellular differentiation, proliferation, migration, tumor suppression, and other fundamental homeostatic cellular mechanisms. The requirement for DAB2 in the canonical TGFβ signaling in fibroblasts suggested that a similar mechanism may exist in immune cells and that DAB2 may contribute to immunological tolerance and suppression of inflammatory responses. In this review, we synthesize the current state of knowledge on the roles of DAB2 in the cells of the innate and adaptive immune system, with particular focus on antigen presenting cells (APCs; macrophages and dendritic cells) and regulatory T cells (Tregs). The emerging role of DAB2 in the immune system is that of an immunoregulatory molecule with significant roles in Treg-mediated immunosuppression, and suppression of TLR signaling in APC. DAB2 itself is downregulated by inflammatory stimuli, an event that likely contributes to the immunogenic function of APC. However, contrary findings have been described in neuroinflammatory disorders, thus suggesting a highly context-specific roles for DAB2 in immune cell regulation. There is need for better understanding of DAB2 regulation and its roles in different immune cells, their specialized sub-populations, and their responses under specific inflammatory conditions.
• Jamwal, D. R., Laubitz, D., Harrison, C. A., Figliuolo da Paz, V., Cox, C. M., Wong, R., Midura-Kiela, M., Gurney, M. A., Besselsen, D. G., Setty, P., Lybarger, L., Bhattacharya, D., Wilson, J. M., Ghishan, F. K., & Kiela, P. R. (2020). Intestinal Epithelial Expression of MHCII Determines Severity of Chemical, T-Cell-Induced, and Infectious Colitis in Mice. Gastroenterology, 159(4), 1342-1356.e6.
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  Intestinal epithelial cells (IECs) provide a barrier that separates the mucosal immune system from the luminal microbiota. IECs constitutively express low levels of major histocompatibility complex (MHC) class II proteins, which are upregulated upon exposure to interferon gamma. We investigated the effects of deleting MHCII proteins specifically in mice with infectious, dextran sodium sulfate (DSS)-, and T-cell-induced colitis.
• Yu, S., Balasubramanian, I., Laubitz, D., Tong, K., Bandyopadhyay, S., Lin, X., Flores, J., Singh, R., Liu, Y., Macazana, C., Zhao, Y., Béguet-Crespel, F., Patil, K., Midura-Kiela, M. T., Wang, D., Yap, G. S., Ferraris, R. P., Wei, Z., Bonder, E. M., , Häggblom, M. M., et al. (2020). Paneth Cell-Derived Lysozyme Defines the Composition of Mucolytic Microbiota and the Inflammatory Tone of the Intestine. Immunity, 53(2), 398-416.e8.
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  Paneth cells are the primary source of C-type lysozyme, a β-1,4-N-acetylmuramoylhydrolase that enzymatically processes bacterial cell walls. Paneth cells are normally present in human cecum and ascending colon, but are rarely found in descending colon and rectum; Paneth cell metaplasia in this region and aberrant lysozyme production are hallmarks of inflammatory bowel disease (IBD) pathology. Here, we examined the impact of aberrant lysozyme production in colonic inflammation. Targeted disruption of Paneth cell lysozyme (Lyz1) protected mice from experimental colitis. Lyz1-deficiency diminished intestinal immune responses to bacterial molecular patterns and resulted in the expansion of lysozyme-sensitive mucolytic bacteria, including Ruminococcus gnavus, a Crohn's disease-associated pathobiont. Ectopic lysozyme production in colonic epithelium suppressed lysozyme-sensitive bacteria and exacerbated colitis. Transfer of R. gnavus into Lyz1 hosts elicited a type 2 immune response, causing epithelial reprograming and enhanced anti-colitogenic capacity. In contrast, in lysozyme-intact hosts, processed R. gnavus drove pro-inflammatory responses. Thus, Paneth cell lysozyme balances intestinal anti- and pro-inflammatory responses, with implications for IBD.
• Zhang, X., Bandyopadhyay, S., Araujo, L. P., Tong, K., Flores, J., Laubitz, D., Zhao, Y., Yap, G., Wang, J., Zou, Q., Ferraris, R., Zhang, L., Hu, W., Bonder, E. M., Kiela, P. R., Coffey, R., Verzi, M. P., Ivanov, I. I., & Gao, N. (2020). Elevating EGFR-MAPK program by a nonconventional Cdc42 enhances intestinal epithelial survival and regeneration. JCI insight, 5(16).
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  The regulatory mechanisms enabling the intestinal epithelium to maintain a high degree of regenerative capacity during mucosal injury remain unclear. Ex vivo survival and clonogenicity of intestinal stem cells (ISCs) strictly required growth response mediated by cell division control 42 (Cdc42) and Cdc42-deficient enteroids to undergo rapid apoptosis. Mechanistically, Cdc42 engaging with EGFR was required for EGF-stimulated, receptor-mediated endocytosis and sufficient to promote MAPK signaling. Proteomics and kinase analysis revealed that a physiologically, but nonconventionally, spliced Cdc42 variant 2 (V2) exhibited stronger MAPK-activating capability. Human CDC42-V2 is transcriptionally elevated in some colon tumor tissues. Accordingly, mice engineered to overexpress Cdc42-V2 in intestinal epithelium showed elevated MAPK signaling, enhanced regeneration, and reduced mucosal damage in response to irradiation. Overproducing Cdc42-V2 specifically in mouse ISCs enhanced intestinal regeneration following injury. Thus, the intrinsic Cdc42-MAPK program is required for intestinal epithelial regeneration, and elevating this signaling cascade is capable of initiating protection from genotoxic injury.
• Daley, S. K., Witte, M. H., Washington, J., Bernas, M., Kiela, P., Thorn, J., Tanoue, N., & Alexander, J. S. (2019). Role of Lymphatic Deficiency in the Pathogenesis and Progression of Inflammatory Bowel Disease to Colorectal Cancer in an Experimental Mouse Model. Inflammatory bowel diseases, 25(12), 1919-1926.
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  Inflammatory bowel disease (IBD) is characterized by chronic inflammation, which can progress to colorectal cancer, with duration of disease being the most important risk factor. Although many factors are involved, the pathogenic link between inflammation and cancer and the role played by the lymphatic system have not been fully investigated. This project uses lymphatic-deficient mice (Angiopoietin-2 [Ang2] knockout) to examine the lymphatic system in the progression of IBD to colorectal cancer.
• Figliuolo da Paz, V., Jamwal, D. R., Gurney, M., Midura-Kiela, M., Harrison, C. A., Cox, C., Wilson, J. M., Ghishan, F. K., & Kiela, P. R. (2019). Rapid Downregulation of DAB2 by Toll-Like Receptor Activation Contributes to a Pro-Inflammatory Switch in Activated Dendritic Cells. Frontiers in immunology, 10, 304.
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  Dendritic cells (DCs) are pivotal in regulating tolerogenic as well as immunogenic responses against microorganisms by directing both the innate and adaptive immune response. In health, phenotypically different DC subsets found in the gut mucosa are maintained in their tolerogenic state but switch to a pro-inflammatory phenotype during infection or chronic autoinflammatory conditions such as inflammatory bowel disease (IBD). The mechanisms that promote the switch among the mucosal DCs from a tolerogenic to an immunogenic, pro-inflammatory phenotype are incompletely understood. We hypothesized that disabled homolog 2 (DAB2), recently described as a negative regulator of DC immunogenicity during their development, is regulated during intestinal inflammation and modulates mucosal DC function. We show that DAB2 is highly expressed in colonic CD11bCD103 DCs, a subset known for its capacity to induce inflammatory Th1/Th17 responses in the colon, and is downregulated predominantly in this DC subset during adoptive T cell transfer colitis. Administration of Dab2-deficient DCs (DC2.4 cells) modulated the course of DSS colitis in wild-type mice, enhanced mucosal expression of , and , and promoted neutrophil recruitment. In bone-marrow derived dendritic cells (BMDC), DAB2 expression correlated with CD11b levels and DAB2 was rapidly and profoundly inhibited by TLR ligands in a TRIF- and MyD88-dependent manner. The negative modulation of DAB2 was biphasic, initiated with a quick drop in DAB2 protein, followed by a sustained reduction in mRNA. DAB2 downregulation promoted a more functional and activated DC phenotype, reduced phagocytosis, and increased CD40 expression after TLR activation. Furthermore, knockout in DCs inhibited autophagy and promoted apoptotic cell death. Collectively, our results highlight the immunoregulatory role for DAB2 in the intestinal dendritic cells and suggest that DAB2 downregulation after microbial exposure promotes their switch to an inflammatory phenotype.
• Jash, A., Zhou, Y. W., Gerardo, D. K., Ripperger, T. J., Parikh, B. A., Piersma, S., Jamwal, D. R., Kiela, P. R., Boon, A. C., Yokoyama, W. M., Hsieh, C. S., & Bhattacharya, D. (2019). ZBTB32 restrains antibody responses to murine cytomegalovirus infections, but not other repetitive challenges. Scientific reports, 9(1), 15257.
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  ZBTB32 is a transcription factor that is highly expressed by a subset of memory B cells and restrains the magnitude and duration of recall responses against hapten-protein conjugates. To define physiological contexts in which ZBTB32 acts, we assessed responses by Zbtb32 mice or bone marrow chimeras against a panel of chronic and acute challenges. Mixed bone marrow chimeras were established in which all B cells were derived from either Zbtb32 mice or control littermates. Chronic infection of Zbtb32 chimeras with murine cytomegalovirus led to nearly 20-fold higher antigen-specific IgG2b levels relative to controls by week 9 post-infection, despite similar viral loads. In contrast, IgA responses and specificities in the intestine, where memory B cells are repeatedly stimulated by commensal bacteria, were similar between Zbtb32 mice and control littermates. Finally, an infection and heterologous booster vaccination model revealed no role for ZBTB32 in restraining primary or recall antibody responses against influenza viruses. Thus, ZBTB32 does not limit recall responses to a number of physiological acute challenges, but does restrict antibody levels during chronic viral infections that periodically engage memory B cells. This restriction might selectively prevent recall responses against chronic infections from progressively overwhelming other antibody specificities.
• Kiela, P. R., Ghishan, F. K., Wilson, J. M., Cox, C. M., Harrison, C. A., Midura-Kiela, M. T., Gurney, M. T., Jamwal, D. R., & Figliuolo da Paz, V. (2019). Rapid downregulation of DAB2 by toll-like receptor activation contributes to a pro-inflammatory switch in activated dendritic cells.. Frontiers in Immunology.
• Harrison, C. A., Laubitz, D., Ohland, C. L., Midura-Kiela, M. T., Patil, K., Besselsen, D. G., Jamwal, D. R., Jobin, C., Ghishan, F. K., & Kiela, P. R. (2018). Microbial dysbiosis associated with impaired intestinal Na/H exchange accelerates and exacerbates colitis in ex-germ free mice. Mucosal immunology, 11(5), 1329-1341.
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  Intestinal epithelial Na/H exchange facilitated by the apical NHE3 (Slc9a3) is a highly regulated process inhibited by intestinal pathogens and in inflammatory bowel diseases. NHE3 mice develop spontaneous, bacterially mediated colitis, and IBD-like dysbiosis. Disruption of epithelial Na/H exchange in IBD may thus represent a host response contributing to the altered gut microbial ecology, and may play a pivotal role in modulating the severity of inflammation in a microbiome-dependent manner. To test whether microbiome fostered in an NHE3-deficient environment is able to drive mucosal immune responses affecting the onset or severity of colitis, we performed a series of cohousing experiments and fecal microbiome transplants into germ-free Rag-deficient or IL-10 mice. We determined that in the settings where the microbiome of NHE3-deficient mice was stably engrafted in the recipient host, it was able accelerate the onset and amplify severity of experimental colitis. NHE3-deficiency was characterized by the reduction in pH-sensitive butyrate-producing Firmicutes families Lachnospiraceae and Ruminococcaceae (Clostridia clusters IV and XIVa), with an expansion of inflammation-associated Bacteroidaceae. We conclude that the microbiome fostered by impaired epithelial Na/H exchange enhances the onset and severity of colitis through disruption of the gut microbial ecology.
• Kędzierska, U., Banasiak, ., Kiela, P., & Majewski, P. M. (2018). Significance of NF-kappaB signaling and PARP1 activity in the TNF-induced inhibition of PHEX gene expression in human osteoblasts. Acta biochimica Polonica, 65(4), 573-571.
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  Although loss of bone mineral density is a common symptom of chronic inflammatory diseases, its mechanisms are still poorly understood. The PHEX gene encodes a Zn-endopeptidase expressed in osteoblasts and contributes to bone mineralization. Data derived from rodents has indicated co-repression of the PHEX gene by the NF-κB pathway and poly(ADP-ribose) polymerase 1 (PARP1). The aim of this study was to determine the molecular mechanism involved in TNF-mediated downregulation of PHEX expression in human osteoblasts and human osteosarcoma cell line. We observed that activation of the NF-κB pathway by TNF was manifested as a nuclear increase in RELA and NFKB1 heterodimer. We found that TNF reduced PHEX expression and the proteasome inhibitor reversed this effect in osteosarcoma cell line. Contrary to the effects seen in rodents, inhibition of PARP1 enzymatic activity did not significantly reverse the effect of TNF on the human PHEX gene expression. EMSA studies showed that the number of adenines in the PHEX proximal promoter is crucial for the transcription factors' interactions within that region. The obtained results support the hypothesis indicating the existence of a molecular mechanism of gene repression that involves a poly adenine-rich region of the proximal gene promoters and PARP1 transcriptional activity.
• Midura-kiela, M. T., Laubitz, D., Kiela, P. R., Gurney, M. A., & Ghishan, F. K. (2018). Decreased Expression of NHE3 in Colon Cancer Epithelium is Associated with DNA Damage, Increased Local Inflammation and Tumor Growth. Gastroenterology, 154(6), S-21. doi:10.1016/s0016-5085(18)30550-x
• Pierucci-Alves, F., Midura-Kiela, M. T., Fleming, S. D., Schultz, B. D., & Kiela, P. R. (2018). Transforming Growth Factor Beta Signaling in Dendritic Cells Is Required for Immunotolerance to Sperm in the Epididymis. Frontiers in immunology, 9, 1882.
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  The epididymis exhibits a less restrictive physical blood-tissue barrier than the testis and, while numerous immunosuppressive factors have been identified in the latter, no mechanisms for epididymal immunotolerance have been identified to date. Therefore, data are currently insufficient to explain how the immune system tolerates the extremely large load of novel antigens expressed on sperm, which become present in the male body after puberty, i.e., long after central tolerance was established. This study tested the hypothesis that transforming growth factor beta (TGFβ) signaling in dendritic cells (DCs) is required for immunotolerance to sperm located in the epididymis, and that male mice lacking TGFβ signaling in DCs would develop severe epididymal inflammation. To test this, we employed adult males, which exhibit a significant reduction of 2 expression and TGFβ signaling in DCs, as reported previously. Results show that males exhibit sperm-specific immune response and severe epididymal leukocytosis. This phenotype is consistent with epididymal loss of immunotolerance to sperm and suggests that TGFβ signaling in DCs is a factor required for a non-inflammatory steady state in the epididymis, and therefore for male tract homeostasis and function.
• Xu, H., Ghishan, F. K., & Kiela, P. R. (2018). SLC9 Gene Family: Function, Expression, and Regulation. Comprehensive Physiology, 8(2), 555-583.
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  The Slc9 family of Na /H exchangers (NHEs) plays a critical role in electroneutral exchange of Na and H in the mammalian intestine as well as other absorptive and secretory epithelia of digestive organs. These transport proteins contribute to the transepithelial Na and water absorption, intracellular pH and cellular volume regulation as well as the electrolyte, acid-base, and fluid volume homeostasis at the systemic level. They also influence the function of other membrane transport mechanisms, affect cellular proliferation and apoptosis as well as cell migration, adherence to the extracellular matrix, and tissue repair. Additionally, they modulate the extracellular milieu to facilitate other nutrient absorption and to regulate the intestinal microbial microenvironment. Na /H exchange is inhibited in selected gastrointestinal diseases, either by intrinsic factors (e.g., bile acids, inflammatory mediators) or infectious agents and associated bacterial toxins. Disrupted NHE activity may contribute not only to local and systemic electrolyte imbalance but also to the disease severity via multiple mechanisms. In this review, we describe the cation proton antiporter superfamily of Na /H exchangers with a particular emphasis on the eight SLC9A isoforms found in the digestive tract, followed by a more integrative description in their roles in each of the digestive organs. We discuss regulatory mechanisms that determine the function of Na /H exchangers as pertinent to the digestive tract, their regulation in pathological states of the digestive organs, and reciprocally, the contribution of dysregulated Na /H exchange to the disease pathogenesis and progression. © 2018 American Physiological Society. Compr Physiol 8:555-583, 2018.
• Ghishan, F. K., & Kiela, P. R. (2017). Vitamins and Minerals in Inflammatory Bowel Disease. Gastroenterology clinics of North America, 46(4), 797-808.
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  Indiscriminate use of multivitamin/mineral supplements in the general population may be misguided, but patients with chronic Inflammatory Bowel Diseases (IBD) should be monitored and compensated for nutritional deficiencies. Mechanistic links between vitamin/mineral deficiencies and IBD pathology has been found for some micronutrients and normalizing their levels is clinically beneficial. Others, like vitamin A, although instinctively desirable, produced disappointing results. Restoring normal levels of the selected micronutrients requires elevated doses to compensate for defects in absorptive or signaling mechanisms. This article describes some aspects of vitamin and mineral deficiencies in IBD, and summarizes pros and cons of supplementation.
• Gurney, M. A., Laubitz, D., Ghishan, F. K., & Kiela, P. R. (2017). Pathophysiology of Intestinal Na+/H+ exchange. Cellular and molecular gastroenterology and hepatology, 3(1), 27-40.
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  Several members of the SLC9A family of Na+/H+ exchangers are expressed in the gut, with varying expression patterns and cellular localization. Not only do they participate in the regulation of basic epithelial cell functions, including control of transepithelial Na+ absorption, intracellular pH (pH i ), cell volume, and nutrient absorption, but also in cellular proliferation, migration, and apoptosis. Additionally, they modulate the extracellular milieu in order to facilitate other nutrient absorption and to regulate the intestinal microbial microenvironment. Na+/H+ exchangers are frequent targets of inhibition in gastrointestinal pathologies, either by intrinsic factors (e.g. bile acids, inflammatory mediators) or infectious agents and associated microbial toxins. Based on emerging evidence, disruption of NHE activity via impaired expression or function of respective isoforms may contribute not only to local and systemic electrolyte imbalance, but also to the disease severity via multiple mechanisms. Here, we review the current state of knowledge about the roles Na+/H+ exchangers play in the pathogenesis of disorders of diverse origin and affecting a range of GI tissues.
• Daley, S., Washington, J., Bernas, M., Meister, E., Thorn, J., Kiela, P., Tanoue, N., Alexander, J. S., & Witte, M. (2016). ROLE OF THE LYMPHATIC SYSTEM IN THE PROGRESSION OF INFLAMMATORY BOWEL DISEASE TO COLORECTAL CANCER IN AN EXPERIMENTAL MOUSE MODEL. JOURNAL OF INVESTIGATIVE MEDICINE.
• Gurney, M., Laubitz, D., Ghishan, F. K., & Kiela, P. R. (2016). Pathophysiology of Intestinal Na+/H+ exchange. Cellular and Molecular Gastroenterology and Hepatology.
• Kiela, P. R., & Ghishan, F. K. (2016). Physiology of Intestinal Absorption and Secretion. Best practice & research. Clinical gastroenterology, 30(2), 145-59.
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  Virtually all nutrients from the diet are absorbed into blood across the highly polarized epithelial cell layer forming the small and large intestinal mucosa. Anatomical, histological, and functional specializations along the gastrointestinal tract are responsible for the effective and regulated nutrient transport via both passive and active mechanisms. In this chapter, we summarize the current state of knowledge regarding the mechanism of intestinal absorption of key nutrients such as sodium, anions (chloride, sulfate, oxalate), carbohydrates, amino acids and peptides, lipids, lipid- and water-soluble vitamins, as well as the major minerals and micronutrients. This outline, including the molecular identity, specificity, and coordinated activities of key transport proteins and genes involved, serves as the background for the following chapters focused on the pathophysiology of acquired and congenital intestinal malabsorption, as well as clinical tools to test and treat malabsorptive symptoms.
• Larmonier, C. B., Shehab, K. W., Laubitz, D., Jamwal, D. R., Ghishan, F. K., & Kiela, P. R. (2016). Transcriptional Reprogramming and Resistance to Colonic Mucosal Injury in Poly(ADP-ribose) Polymerase 1 (PARP1)-deficient Mice. The Journal of biological chemistry, 291(17), 8918-30.
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  Poly(ADP-ribose) polymerases (PARPs) synthesize and bind branched polymers of ADP-ribose to acceptor proteins using NAD as a substrate and participate in the control of gene transcription and DNA repair. PARP1, the most abundant isoform, regulates the expression of proinflammatory mediator cytokines, chemokines, and adhesion molecules, and inhibition of PARP1 enzymatic activity reduced or ameliorated autoimmune diseases in several experimental models, including colitis. However, the mechanism(s) underlying the protective effects of PARP1 inhibition in colitis and the cell types in which Parp1 deletion has the most significant impact are unknown. The objective of the current study was to determine the impact of Parp1 deletion on the innate immune response to mucosal injury and on the gut microbiome composition. Parp1 deficiency was evaluated in DSS-induced colitis in WT, Parp1(-/-), Rag2(-/-), and Rag2(-/-)×Parp1(-/-) double knock-out mice. Genome-wide analysis of the colonic transcriptome and fecal 16S amplicon profiling was performed. Compared with WT, we demonstrated that Parp1(-/-) were protected from dextran-sulfate sodium-induced colitis and that this protection was associated with a dramatic transcriptional reprogramming in the colon. PARP1 deficiency was also associated with a modulation of the colonic microbiota (increases relative abundance of Clostridia clusters IV and XIVa) and a concomitant increase in the frequency of mucosal CD4(+)CD25(+) Foxp3(+) regulatory T cells. The protective effects conferred by Parp1 deletion were lost in Rag2(-/-) × Parp1(-/-) mice, highlighting the role of the adaptive immune system for full protection.
• Laubitz, D., Harrison, C. A., Midura-Kiela, M. T., Ramalingam, R., Larmonier, C. B., Chase, J. H., Caporaso, J. G., Besselsen, D. G., Ghishan, F. K., & Kiela, P. R. (2016). Reduced Epithelial Na+/H+ Exchange Drives Gut Microbial Dysbiosis and Promotes Inflammatory Response in T Cell-Mediated Murine Colitis. PloS one, 11(4), e0152044.
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  Inflammatory bowel diseases (IBD) are associated with functional inhibition of epithelial Na+/H+ exchange. In mice, a selective disruption of NHE3 (Slc9a3), a major apical Na+/H+ exchanger, also promotes IBD-like symptoms and gut microbial dysbiosis. We hypothesized that disruption of Na+/H+ exchange is necessary for the development of dysbiosis, which promotes an exacerbated mucosal inflammatory response. Therefore, we performed a temporal analysis of gut microbiota composition, and mucosal immune response to adoptive T cell transfer was evaluated in Rag2-/- and NHE3-/-/Rag2-/- (DKO) mice with and without broad-spectrum antibiotics. Microbiome (16S profiling), colonic histology, T cell and neutrophil infiltration, mucosal inflammatory tone, and epithelial permeability were analyzed. In adoptive T cell transfer colitis model, Slc9a3 status was the most significant determinant of gut microbial community. In DKO mice, NHE3-deficiency and dysbiosis were associated with dramatically accelerated and exacerbated disease, with rapid body weight loss, increased mucosal T cell and neutrophil influx, increased mucosal cytokine expression, increased permeability, and expansion of CD25-FoxP3+ Tregs; this enhanced susceptibility was alleviated by oral broad-spectrum antibiotics. Based on these results and our previous work, we postulate that epithelial electrolyte homeostasis is an important modulator in the progression of colitis, acting through remodeling of the gut microbial community.
• Radhakrishnan, V. M., Kiela, P. R., Gilpatrick, M. M., Ghishan, F. K., & Dehdashti, N. (2016). Post Transcriptional Regulation of Colonic Cav1.3 by IFNγ in Colitis: Potential Implications for IBD-Associated Impaired Intestinal Ca2+Absorption and Bone Loss. Gastroenterology, 150(4), S119. doi:10.1016/s0016-5085(16)30508-x
• Xu, H., Laubitz, D., Kiela, P. R., Gurney, M. A., & Ghishan, F. K. (2016). Intrinsic Effects of Reduced NHE3 Activity in Intestinal Epithelial Cells. Gastroenterology, 150(4), S114. doi:10.1016/s0016-5085(16)30488-7
• Harrison, C. A., Laubitz, D., Midura-Kiela, M. T., Jamwal, D. R., Besselsen, D. G., Ghishan, F. K., & Kiela, P. R. (2019). Sexual Dimorphism in the Response to Broad-spectrum Antibiotics During T Cell-mediated Colitis. Journal of Crohn's & colitis, 13(1), 115-126.
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  Broad-spectrum antibiotics [Abx], including combination therapy with ciprofloxacin and metronidazole, are often prescribed during the treatment of inflammatory bowel disease [IBD] to alleviate symptoms, but with varying success. In this pilot study, we studied the effects of Abx on the course of experimental colitis, with a particular focus on sex as a determinant of the microbial and inflammatory responses.
• Jamwal, D. R., Marati, R. V., Harrison, C. A., Midura-Kiela, M. T., Figliuolo Paz, V. R., Besselsen, D. G., Ghishan, F. K., & Kiela, P. R. (2020). Total CD3 T Cells Are Necessary and Sufficient to Induce Colitis in Immunodeficient Mice With Dendritic Cell-Specific Deletion of TGFbR2: A Novel IBD Model to Study CD4 and CD8 T-Cell Interaction. Inflammatory bowel diseases, 26(2), 229-241. doi:10.1093/ibd/izz191
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  Inflammatory bowel disease (IBD) is a multifactorial disorder, with the innate and adaptive immune cells contributing to disease initiation and progression. However, the intricate cross-talk between immune cell lineages remains incompletely understood. The role of CD8+ T cells in IBD pathogenesis has been understudied, largely due to the lack of appropriate models.
• Kiela, P. R., Jobin, C., Ghishan, F. K., Jamwal, D. R., Besselsen, D. G., Patil, K., Midura-Kiela, M. T., Ohland, C. L., Lubitz, D., & Harrison, C. A. (2017). Microbial Dysbiosis Associated with Impaired Intestinal Na+/H+ Exchange Accelerates and Exacerbates Colitis in Gnotobiotic Mice. Mucosal Immunology.
• Radhakrishnan, V. M., Gilpatrick, M. M., Parsa, N. A., Kiela, P. R., & Ghishan, F. K. (2017). Expression of Cav1.3 calcium channel in the human and mouse colon: post-transcriptional inhibition by IFNγ. American journal of physiology. Gastrointestinal and liver physiology, ajpgi.00394.2016.
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  It has been hypothesized that apically expressed L-type Ca(2+) channel Cav1.3 (encoded by CACNA1D gene) contributes towards an alternative TRPV6-independent route of intestinal epithelial Ca(2+) absorption, especially during digestion when high luminal concentration of Ca(2+) and other nutrients limit TRPV6 contribution. We and others have implicated altered expression and activity of key mediators of intestinal and renal Ca(2+) (re)absorption as contributors to negative systemic Ca2+ balance and bone loss in intestinal inflammation. Here, we investigated the effects of experimental colitis and related inflammatory mediators on colonic Cav1.3 expression. We confirmed Cav1.3 expression within the segments of the mouse and human gastrointestinal tract. Consistent with available microarray data (GEO database) from IBD patients, mouse colonic expression of Cav1.3 was significantly reduced in TNBS colitis. In vitro, IFNγ most potently reduced Cav1.3 expression. We reproduced these findings in vivo with wild-type and Stat1(-/-) mice injected with IFNγ. The observed effect in Stat1(-/-) suggested a non-canonical transcriptional repression or a post-transcriptional mechanism. In support of the latter, we observed no effect on the cloned Cav1.3 gene promoter activity, and accelerated Cav1.3 mRNA decay rate in IFNγ-treated HCT116 cells. While the relative contribution of Cav1.3 to intestinal Ca(2+) absorption and its value as a therapeutic target remain to be established, we postulate that Cav1.3 downregulation in IBD may contribute to the negative systemic Ca(2+) balance, increased bone resorption, and to reduced bone mineral density in IBD patients.
• Typpo, K. V., Larmonier, C. B., Deschenes, J., Redford, D., Kiela, P. R., & Ghishan, F. K. (2015). Clinical characteristics associated with postoperative intestinal epithelial barrier dysfunction in children with congenital heart disease. Pediatric critical care medicine : a journal of the Society of Critical Care Medicine and the World Federation of Pediatric Intensive and Critical Care Societies, 16(1), 37-44.
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  Children with congenital heart disease have loss of intestinal epithelial barrier function, which increases their risk for postoperative sepsis and organ dysfunction. We do not understand how postoperative cardiopulmonary support or the inflammatory response to cardiopulmonary bypass might alter intestinal epithelial barrier function. We examined variation in a panel of plasma biomarkers to reflect intestinal epithelial barrier function (cellular and paracellular) after cardiopulmonary bypass and in response to routine ICU care.
• Typpo, K., Larmonier, C., Deschenes, J., Kiela, P., & Ghishan, F. (2015). EARLY PARENTERAL NUTRITION IMPROVES INTESTINAL BARRIER FUNCTION: RESULTS FROM A PILOT RCT. CRITICAL CARE MEDICINE, 43(12).
• Ghishan, F. K., & Kiela, P. R. (2014). Epithelial transport in inflammatory bowel diseases. Inflammatory bowel diseases, 20(6), 1099-109.
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  The epithelium of the gastrointestinal tract is one of the most versatile tissues in the organism, responsible for providing a tight barrier between dietary and bacterial antigens and the mucosal and systemic immune system while maintaining efficient digestive and absorptive processes to ensure adequate nutrient and energy supply. Inflammatory bowel diseases (Crohn's disease and ulcerative colitis) are associated with a breakdown of both functions, which in some cases are clearly interrelated. In this updated literature review, we focus on the effects of intestinal inflammation and the associated immune mediators on selected aspects of the transepithelial transport of macronutrients and micronutrients. The mechanisms responsible for nutritional deficiencies are not always clear and could be related to decreased intake, malabsorption, and excess losses. We summarize the known causes of nutrient deficiencies and the mechanism of inflammatory bowel disease-associated diarrhea. We also overview the consequences of impaired epithelial transport, which infrequently transcend its primary purpose to affect the gut microbial ecology and epithelial integrity. Although some of those regulatory mechanisms are relatively well established, more work needs to be done to determine how inflammatory cytokines can alter the transport process of nutrients across the gastrointestinal and renal epithelia.
• Radhakrishnan, V. M., Kojs, P., Young, G., Ramalingam, R., Jagadish, B., Mash, E. A., Martinez, J. D., Ghishan, F. K., & Kiela, P. R. (2014). pTyr421 cortactin is overexpressed in colon cancer and is dephosphorylated by curcumin: involvement of non-receptor type 1 protein tyrosine phosphatase (PTPN1). PloS one, 9(1), e85796.
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  Cortactin (CTTN), first identified as a major substrate of the Src tyrosine kinase, actively participates in branching F-actin assembly and in cell motility and invasion. CTTN gene is amplified and its protein is overexpressed in several types of cancer. The phosphorylated form of cortactin (pTyr(421)) is required for cancer cell motility and invasion. In this study, we demonstrate that a majority of the tested primary colorectal tumor specimens show greatly enhanced expression of pTyr(421)-CTTN, but no change at the mRNA level as compared to healthy subjects, thus suggesting post-translational activation rather than gene amplification in these tumors. Curcumin (diferulolylmethane), a natural compound with promising chemopreventive and chemosensitizing effects, reduced the indirect association of cortactin with the plasma membrane protein fraction in colon adenocarcinoma cells as measured by surface biotinylation, mass spectrometry, and Western blotting. Curcumin significantly decreased the pTyr(421)-CTTN in HCT116 cells and SW480 cells, but was ineffective in HT-29 cells. Curcumin physically interacted with PTPN1 tyrosine phosphatases to increase its activity and lead to dephosphorylation of pTyr(421)-CTTN. PTPN1 inhibition eliminated the effects of curcumin on pTyr(421)-CTTN. Transduction with adenovirally-encoded CTTN increased migration of HCT116, SW480, and HT-29. Curcumin decreased migration of HCT116 and SW480 cells which highly express PTPN1, but not of HT-29 cells with significantly reduced endogenous expression of PTPN1. Curcumin significantly reduced the physical interaction of CTTN and pTyr(421)-CTTN with p120 catenin (CTNND1). Collectively, these data suggest that curcumin is an activator of PTPN1 and can reduce cell motility in colon cancer via dephosphorylation of pTyr(421)-CTTN which could be exploited for novel therapeutic approaches in colon cancer therapy based on tumor pTyr(421)-CTTN expression.
• Radhakrishnan, V. M., Ramalingam, R., Larmonier, C. B., Thurston, R. D., Laubitz, D., Midura-Kiela, M. T., McFadden, R. T., Kuro-O, M., Kiela, P. R., & Ghishan, F. K. (2014). Post-Translational Loss of Renal TRPV5 Calcium Channel Expression, Ca2+ Wasting, and Bone Loss in Experimental Colitis. GASTROENTEROLOGY, 145(3), 613-624.
• Ramalingam, R., Midura-kiela, M. T., Mcfadden, R. T., Larmonier, C. B., Kiela, P. R., Harrison, C. A., Ghishan, F. K., Chase, J., Caporaso, G., & Besselsen, D. G. (2014). The Role of Curcumin in Modulating Colonic Microbiota During Colitis and Colon Cancer Prevention. Gastroenterology, 146(5), S-66. doi:10.1016/s0016-5085(14)60234-1
• Hua, P., Xu, H., Uno, J. K., Lipko, M. A., Dong, J., Kiela, P. R., & Ghishan, F. K. (2013). Sp1 and Sp3 mediate NHE2 gene transcription in the intestinal epithelial cells. AMERICAN JOURNAL OF PHYSIOLOGY-GASTROINTESTINAL AND LIVER PHYSIOLOGY, 293(1), G146-G153.
• Kiela, P. R., Ghishan, F. K., & Johnson, L. (2013). Na+-H+ Exchange in Mammalian Digestive Tract. PHYSIOLOGY OF THE GASTROINTESTINAL TRACT, VOLS 1 AND 2, 4TH EDITION, 1847-1879.
• Kiela, P., Midura, A., Kuscuoglu, N., Jolad, S., Solyom, A., Besselsen, D., Timmermann, B., & Ghishan, F. (2013). Effects of Boswellia serrata in mouse models of chemically induced colitis. AMERICAN JOURNAL OF PHYSIOLOGY-GASTROINTESTINAL AND LIVER PHYSIOLOGY, 288(4), G798-G808.
• Larmonier, C. B., Laubitz, D., Hill, F. M., Shehab, K. W., Lipinski, L., Midura-Kiela, M. T., McFadden, R. M., Ramalingam, R., Hassan, K. A., Golebiewski, M., Besselsen, D. G., Ghishan, F. K., & Kiela, P. R. (2013). Reduced colonic microbial diversity is associated with colitis in NHE3-deficient mice. American journal of physiology. Gastrointestinal and liver physiology, 305(10), G667-77.
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  Chronic inflammation and enteric infections are frequently associated with epithelial Na(+)/H(+) exchange (NHE) inhibition. Alterations in electrolyte transport and in mucosal pH associated with inflammation may represent a key mechanism leading to changes in the intestinal microbial composition. NHE3 expression is essential for the maintenance of the epithelial barrier function. NHE3(-/-) mice develop spontaneous distal chronic colitis and are highly susceptible to dextran sulfate (DSS)-induced mucosal injury. Spontaneous colitis is reduced with broad-spectrum antibiotics treatment, thus highlighting the importance of the microbiota composition in NHE3 deficiency-mediated colitis. We herein characterized the colonic microbiome of wild-type (WT) and NHE3(-/-) mice housed in a conventional environment using 454 pyrosequencing. We demonstrated a significant decrease in the phylogenetic diversity of the luminal and mucosal microbiota of conventional NHE3(-/-) mice compared with WT. Rederivation of NHE3(-/-) mice from conventional to a barrier facility eliminated the signs of colitis and decreased DSS susceptibility. Reintroduction of the conventional microflora into WT and NHE3(-/-) mice from the barrier facility resulted in the restoration of the symptoms initially described in the conventional environment. Interestingly, qPCR analysis of the microbiota composition in mice kept in the barrier facility compared with reconventionalized mice showed a significant reduction of Clostridia classes IV and XIVa. Therefore, the gut microbiome plays a prominent role in the pathogenesis of colitis in NHE3(-/-) mice, and, reciprocally, NHE3 also plays a critical role in shaping the gut microbiota. NHE3 deficiency may be a critical contributor to dysbiosis observed in patients with inflammatory bowel disease.
• Larmonier, C. B., McFadden, R. M., Hill, F. M., Schreiner, R., Ramalingam, R., Besselsen, D. G., Ghishan, F. K., & Kiela, P. R. (2013). High vitamin D3 diet administered during active colitis negatively affects bone metabolism in an adoptive T cell transfer model. American journal of physiology. Gastrointestinal and liver physiology, 305(1), G35-46.
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  Decreased bone mineral density (BMD) represents an extraintestinal complication of inflammatory bowel disease (IBD). Vitamin D₃ has been considered a viable adjunctive therapy in IBD. However, vitamin D₃ plays a pleiotropic role in bone modeling and regulates the bone formation-resorption balance, depending on the physiological environment, and supplementation during active IBD may have unintended consequences. We evaluated the effects of vitamin D₃ supplementation during the active phase of disease on colonic inflammation, BMD, and bone metabolism in an adoptive IL-10-/- CD4⁺ T cell transfer model of chronic colitis. High-dose vitamin D₃ supplementation for 12 days during established disease had negligible effects on mucosal inflammation. Plasma vitamin D₃ metabolites correlated with diet, but not disease, status. Colitis significantly reduced BMD. High-dose vitamin D₃ supplementation did not affect cortical bone but led to a further deterioration of trabecular bone morphology. In mice fed a high vitamin D₃ diet, colitis more severely impacted bone formation markers (osteocalcin and bone alkaline phosphatase) and increased bone resorption markers, ratio of receptor activator of NF-κB ligand to osteoprotegrin transcript, plasma osteoprotegrin level, and the osteoclast activation marker tartrate-resistant acid phosphatase (ACp5). Bone vitamin D receptor expression was increased in mice with chronic colitis, especially in the high vitamin D₃ group. Our data suggest that vitamin D₃, at a dose that does not improve inflammation, has no beneficial effects on bone metabolism and density during active colitis or may adversely affect BMD and bone turnover. These observations should be taken into consideration in the planning of further clinical studies with high-dose vitamin D₃ supplementation in patients with active IBD.
• Radhakrishnan, V. M., Ramalingam, R., Larmonier, C. B., Thurston, R. D., Laubitz, D., Midura-Kiela, M. T., McFadden, R. M., Kuro-O, M., Kiela, P. R., & Ghishan, F. K. (2013). Post-translational loss of renal TRPV5 calcium channel expression, Ca(2+) wasting, and bone loss in experimental colitis. Gastroenterology, 145(3), 613-24.
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  Dysregulated Ca(2+) homeostasis likely contributes to the etiology of inflammatory bowel disease-associated loss of bone mineral density. Experimental colitis leads to decreased expression of Klotho, a protein that supports renal Ca(2+) reabsorption by stabilizing the transient receptor potential vanilloid 5 (TRPV5) channel on the apical membrane of distal tubule epithelial cells.
• Shehab, K. W., Woodford, R. T., Shehab, K. W., Midura-kiela, M. T., Laubitz, D., Larmonier, C. B., Kiela, P. R., Hill, F. M., Golebiewski, M., Ghishan, F. K., & Besselsen, D. G. (2013). Alteration of the Gut Microbiome in NHE3-Deficient Mice. Gastroenterology, 144(5), S-133. doi:10.1016/s0016-5085(13)60479-5
• Borbon, I. A., Hillman, Z., Duran, E., Kiela, P. R., Frautschy, S. A., & Erickson, R. P. (2012). Lack of efficacy of curcumin on neurodegeneration in the mouse model of Niemann-Pick C1. Pharmacology, biochemistry, and behavior, 101(1), 125-31.
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  In order to determine the efficacy of curcumin in ameliorating symptoms of neurodegeneration in the mouse model of Niemann-Pick C1, a variety of formulations and dosages of curcumin, one comparable to one previously reported as efficacious, were provided orally to Npc1(-/-)mice. Plasma levels of curcumin, survival, tests of motor performance, and memory (in some cases) were performed. We found variable, but mild, increases in survival (1.5% to 18%). The greatest increased survival occurred with the highest dose (which was unformulated) while the control for the lipidated formulation (containing phosphatidylcholine and stearic acid) had an equivalent impact and other formulations, while not significantly increased, are also not statistically different in effect from the highest dose. We conclude that curcumin is not a highly efficacious treatment for neurodegeneration in Npc1(-/-) mice. Phosphatidylcholine and stearic acid should be studied further.
• Collins, J., Xu, H., Kiela, P., Zeng, J., & Ghishan, F. (2012). Functional and molecular characterization of NHE3 expression during ontogeny in rat jejunal epithelium. AMERICAN JOURNAL OF PHYSIOLOGY-CELL PHYSIOLOGY, 273(6), C1937-C1946.
• KIELA, P., PIERZYNOWSKI, S., OLDAK, T., CEREGRZYN, M., ERLANSONALBERTSSON, C., WIECHETEK, M., & GARWACKI, S. (2012). THE EFFECT OF ENTEROSTATIN ON PIG DUODENAL, JEJUNAL AND ILEAL MOTILITY IN-VITRO. BIOMEDICAL RESEARCH-TOKYO, 15, 303-307.
• Kiela, P. R., & Ghishan, F. K. (2012). Recent advances in the renal-skeletal-gut axis that controls phosphate homeostasis. LABORATORY INVESTIGATION, 89(1), 7-14.
• Kiela, P. R., Kuscuoglu, N., Midura, A. J., Midura-Kiela, M. T., Larmonier, C. B., Lipko, M., & Ghishan, F. K. (2012). Molecular mechanism of rat NHE3 gene promoter regulation by sodium butyrate. AMERICAN JOURNAL OF PHYSIOLOGY-CELL PHYSIOLOGY, 293(1), C64-C74.
• Kiela, P., Ghishan, F. K., & Kiela, P. R. (2012). Small intestinal ion transport. Current opinion in gastroenterology, 28(2).
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  In this review, we focus on the recent (March 2010 to September 2011) advances in small intestinal ion transport, with particular emphasis on sodium, chloride, bicarbonate, and calcium transport mechanisms under physiological and pathophysiological conditions.
• Kiela, P., Ramalingam, R., Larmonier, C. B., Thurston, R. D., Midura-Kiela, M. T., Zheng, S. G., Ghishan, F. K., & Kiela, P. R. (2012). Dendritic cell-specific disruption of TGF-β receptor II leads to altered regulatory T cell phenotype and spontaneous multiorgan autoimmunity. Journal of immunology (Baltimore, Md. : 1950), 189(8).
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  In vitro data and transgenic mouse models suggest a role for TGF-β signaling in dendritic cells (DCs) to prevent autoimmunity primarily through maintenance of DCs in their immature and tolerogenic state characterized by low expression of MHC class II (MHCII) and costimulatory molecules and increased expression of IDO, among others. To test whether a complete lack of TGF-β signaling in DCs predisposes mice to spontaneous autoimmunity and to verify the mechanisms implicated previously in vitro, we generated conditional knockout (KO) mice with Cre-mediated DC-specific deletion of Tgfbr2 (DC-Tgfbr2 KO). DC-Tgfbr2 KO mice die before 15 wk of age with multiorgan autoimmune inflammation and spontaneous activation of T and B cells. Interestingly, there were no significant differences in the expression of MHCII, costimulatory molecules, or IDO in secondary lymphoid organ DCs, although Tgfbr2-deficient DCs were more proinflammatory in vitro and in vivo. DC-Tgfbr2 KO showed attenuated Foxp3 expression in regulatory T cells (Tregs) and abnormal expansion of CD25(-)Foxp3(+) Tregs in vivo. Tgfbr2-deficient DCs secreted elevated levels of IFN-γ and were not capable of directing Ag-specific Treg conversion unless in the presence of anti-IFN-γ blocking Ab. Adoptive transfer of induced Tregs into DC-Tgfbr2 KO mice partially rescued the phenotype. Therefore, in vivo, TGF-β signaling in DCs is critical in the control of autoimmunity through both Treg-dependent and -independent mechanisms, but it does not affect MHCII and costimulatory molecule expression.
• Lan, Q., Zhou, X., Fan, H., Chen, M., Wang, J., Ryffel, B., Brand, D., Ramalingam, R., Kiela, P. R., Horwitz, D. A., Liu, Z., & Zheng, S. G. (2012). Polyclonal CD4+Foxp3+ Treg cells induce TGFβ-dependent tolerogenic dendritic cells that suppress the murine lupus-like syndrome. Journal of molecular cell biology, 4(6), 409-19.
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  Interplay between Foxp3(+) regulatory T cells (Treg) and dendritic cells (DCs) maintains immunologic tolerance, but the effects of each cell on the other are not well understood. We report that polyclonal CD4(+)Foxp3(+) Treg cells induced ex vivo with transforming growth factor beta (TGFβ) (iTreg) suppress a lupus-like chronic graft-versus-host disease by preventing the expansion of immunogenic DCs and inducing protective DCs that generate additional recipient CD4(+)Foxp3(+) cells. The protective effects of the transferred iTreg cells required both interleukin (IL)-10 and TGFβ, but the tolerogenic effects of the iTreg on DCs, and the immunosuppressive effects of these DCs were exclusively TGFβ-dependent. The iTreg were unable to tolerize Tgfbr2-deficient DCs. These results support the essential role of DCs in 'infectious tolerance' and emphasize the central role of TGFβ in protective iTreg/DC interactions in vivo.
• Mash, E. A., Kiela, P. R., Navath, S., Rao, V., Woodford, R. T., Midura-Kiela, M. T., Ahad, A. M., & Alleti, R. (2012). Design, Synthesis, and Testing of a Molecular Truck for Colonic Delivery of 5-Aminosalicylic Acid. ACS Medicinal Chemistry Letters, 3(9), 710-714. doi:10.1021/ml300086c
• Midura-Kiela, M. T., Radhakrishnan, V. M., Larmonier, C. B., Laubitz, D., Ghishan, F. K., & Kiela, P. R. (2012). Curcumin inhibits interferon-gamma signaling in colonic epithelial cells. AMERICAN JOURNAL OF PHYSIOLOGY-GASTROINTESTINAL AND LIVER PHYSIOLOGY, 302(1), G85-G96.
• Midura-Kiela, M. T., Radhakrishnan, V. M., Larmonier, C. B., Laubitz, D., Ghishan, F. K., & Kiela, P. R. (2012). Curcumin inhibits interferon-γ signaling in colonic epithelial cells. American journal of physiology. Gastrointestinal and liver physiology, 302(1), G85-96.
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  Curcumin (diferulolylmethane) is an anti-inflammatory phenolic compound found effective in preclinical models of inflammatory bowel diseases (IBD) and in ulcerative colitis patients. Pharmacokinetics of curcumin and its poor systemic bioavailability suggest that it targets preferentially intestinal epithelial cells. The intestinal epithelium, an essential component of the gut innate defense mechanisms, is profoundly affected by IFN-γ, which can disrupt the epithelial barrier function, prevent epithelial cell migration and wound healing, and prime epithelial cells to express major histocompatibility complex class II (MHC-II) molecules and to serve as nonprofessional antigen-presenting cells. In this report we demonstrate that curcumin inhibits IFN-γ signaling in human and mouse colonocytes. Curcumin inhibited IFN-γ-induced gene transcription, including CII-TA, MHC-II genes (HLA-DRα, HLA-DPα1, HLA-DRβ1), and T cell chemokines (CXCL9, 10, and 11). Acutely, curcumin inhibited Stat1 binding to the GAS cis-element, prevented Stat1 nuclear translocation, and reduced Jak1 phosphorylation and phosphorylation of Stat1 at Tyr(701). Longer exposure to curcumin led to endocytic internalization of IFNγRα followed by lysosomal fusion and degradation. In summary, curcumin acts as an IFN-γ signaling inhibitor in colonocytes with biphasic mechanisms of action, a phenomenon that may partially account for the beneficial effects of curcumin in experimental colitis and in human IBD.
• Navath, S., Rao, V., Woodford, R. M., Midura-Kiela, M. T., Ahad, A. M., Alleti, R., Kiela, P. R., & Mash, E. A. (2012). Design, Synthesis, and Testing of a Molecular Truck for Colonic Delivery of 5-Aminosalicylic Acid. ACS medicinal chemistry letters, 3(9), 710-714.
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  A molecular scaffold bearing eight terminal alkyne groups was synthesized from sucrose. Eight copies of an azide-terminated, azo-linked precursor to 5-aminosalicylic acid were attached to the scaffold via copper(I)-catalyzed azide-alkyne cycloaddition. The resulting compound was evaluated in a DSS model of colitis in BALB/c mice against sulfasalazine as a control. Two independent studies verified that the novel pro-drug, administered in a dose calculated to result in an equimolar 5-ASA yield, outperformed sulfasalazine in terms of protection from mucosal inflammation and T cell activation. A separate study established that 5-ASA appeared in feces produced 24-48 hours following administration of the pro-drug. Thus, a new, orally administered pro-drug form of 5-aminosalicylic acid has been developed and successfully demonstrated.
• Puchala, R., Zabielski, R., Lesniewska, ., Gralak, M., Kiela, P., & Barej, W. (2012). Influence of duodenal infusion of betaine or choline on blood metabolites and duodenal electrical activity in Friesian calves. JOURNAL OF AGRICULTURAL SCIENCE, 131, 321-327.
• Typpo, K. V., Theodorou, A. A., Larmonier, C. B., Kiela, P. R., Ghishan, F. K., & Deschenes, J. (2012). 1058: INTESTINAL INJURY IN CHILDREN AFTER CARDIOPULMONARY BYPASS. Critical Care Medicine, 40, 1-328. doi:10.1097/01.ccm.0000425271.92762.5c
• Xu, H., Collins, J., Bai, L., Kiela, P., & Ghishan, F. (2012). Regulation of the human sodium-phosphate cotransporter NaPi-IIb gene promoter by epidermal growth factor. AMERICAN JOURNAL OF PHYSIOLOGY-CELL PHYSIOLOGY, 280(3), C628-C636.
• Xu, L., Dixit, M., Nullmeyer, K., Xu, H., Kiela, P., Lynch, R., & Ghishan, F. (2012). Regulation of Na+/H+ exchanger-NHE3 by angiotensin-II in OKP cells. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES, 1758(4), 519-526.
• Collins, J., Kiela, P., Xu, H., & Ghishan, F. (2011). Expression of rat, renal NHE2 and NHE3 during postnatal developmental. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES, 1464(1), 7-17.
• Kiela, P. R., & Ghishan, F. K. (2011). Advances in the understanding of mineral and bone metabolism in inflammatory bowel diseases. American Journal of Physiology-Gastrointestinal and Liver Physiology, 300(2), G191-G201. doi:10.1152/ajpgi.00496.2010
• Kiela, P., Ghishan, F. K., & Kiela, P. R. (2011). Advances in the understanding of mineral and bone metabolism in inflammatory bowel diseases. American journal of physiology. Gastrointestinal and liver physiology, 300(2).
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  Chronic inflammatory disorders such as inflammatory bowel diseases (IBDs) affect bone metabolism and are frequently associated with the presence of osteopenia, osteoporosis, and increased risk of fractures. Although several mechanisms may contribute to skeletal abnormalities in IBD patients, inflammation and inflammatory mediators such as TNF, IL-1β, and IL-6 may be the most critical. It is not clear whether the changes in bone metabolism leading to decreased mineral density are the result of decreased bone formation, increased bone resorption, or both, with varying results reported in experimental models of IBD and in pediatric and adult IBD patients. New data, including our own, challenge the conventional views, and contributes to the unraveling of an increasingly complex network of interactions leading to the inflammation-associated bone loss. Since nutritional interventions (dietary calcium and vitamin D supplementation) are of limited efficacy in IBD patients, understanding the pathophysiology of osteopenia and osteoporosis in Crohn's disease and ulcerative colitis is critical for the correct choice of available treatments or the development of new targeted therapies. In this review, we discuss current concepts explaining the effects of inflammation, inflammatory mediators and their signaling effectors on calcium and phosphate homeostasis, osteoblast and osteoclast function, and the potential limitations of vitamin D used as an immunomodulator and anabolic hormone in IBD.
• Kiela, P., Ghishan, F. K., & Kiela, P. R. (2011). From probiotics to therapeutics: another step forward?. The Journal of clinical investigation, 121(6).
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  Preclinical studies with probiotics continue to unravel mechanisms of cytoprotection and suggest that approaches utilizing microbial products as therapeutics in acute and chronic gastrointestinal disorders could be effective. However, clinical trials using these bacteria have thus far been inconsistent. In this issue of the JCI, Yan et al. describe a novel mechanism of cytoprotection by p40, a soluble product of Lactobacillus rhamnosus GG, mediated via EGFR. The efficacy of p40 in three models of chemically induced colitis indicates tremendous therapeutic potential, though this finding will need to be verified in human patients.
• Kiela, P., LeSueur, J., Collins, J., & Ghishan, F. (2011). Transcriptional regulation of the rat NHE3 gene - Functional interactions between GATA-5 and Sp family transcription factors. JOURNAL OF BIOLOGICAL CHEMISTRY, 278(8), 5659-5668.
• Larmonier, C. B., Laubitz, D., Hill, F. M., Shehab, K. W., Lipinski, L., Midura-Kiela, M. T., McFadden, R. T., Ramalingam, R., Hassan, K. A., Golebiewski, M., Besselsen, D. G., Ghishan, F. K., & Kiela, P. R. (2011). Reduced colonic microbial diversity is associated with colitis in NHE3-deficient mice. AMERICAN JOURNAL OF PHYSIOLOGY-GASTROINTESTINAL AND LIVER PHYSIOLOGY, 305(10), G667-G677.
• Larmonier, C. B., Laubitz, D., Thurston, R. D., Bucknam, A. L., Hill, F. M., Midura-Kiela, M., Ramalingam, R., Kiela, P. R., & Ghishan, F. K. (2011). NHE3 modulates the severity of colitis in IL-10-deficient mice. American journal of physiology. Gastrointestinal and liver physiology, 300(6), G998-G1009.
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  NHE3, the major intestinal Na(+)/H(+) exchanger, was shown to be downregulated and/or inhibited in patients with inflammatory bowel disease (IBD), a phenomenon believed to contribute to inflammation-associated diarrhea. NHE3(-/-) mice spontaneously develop colitis and demonstrate high susceptibility to dextran sulfate-induced mucosal injury. We investigated the effects of NHE3 deficiency on the development of chronic colitis in an IL-10 knockout (KO) mouse model of Crohn's disease. NHE3(-/-) mice were first backcrossed to 129/SvEv mice for >10 generations, with no apparent changes in their survival or phenotype. These mice were crossed with IL-10(-/-) mice on the same genetic background, and the phenotypes of 10-wk-old wild-type (WT), IL-10(-/-), NHE3(-/-), and IL-10(-/-)/NHE3(-/-) (double-KO) mice were studied. Histological and immunohistochemical examination of the colon established important architectural alterations, including increased neutrophilic and mononuclear cell infiltration in double- compared with single-KO mice. Double-KO mice demonstrated increased colonic expression of neutrophil collagenase matrix metalloproteinase-8 and the chemokines macrophage inflammatory protein-2, CXCL1, CXCL10, and CXCL11. Colonic IFNγ, IL-17, and IL-12/23 p40 protein secretion was significantly increased in double- compared with single-KO mice. IL-10(-/-)/NHE3(-/-) mouse colonic epithelium exhibited increased hallmarks of apoptosis, including a significantly increased number of cleaved caspase-3-positive surface epithelial cells. These results highlight the importance of NHE3 in the maintenance of intestinal barrier integrity and in modulating the inflammatory process in IL-10-deficient mice. Chronic NHE3 inhibition or underexpression observed in IBD may therefore contribute to the pathogenesis of IBD by influencing the extent of the epithelial barrier defect and affect the ultimate degree of inflammation.
• Larmonier, C. B., McFadden, R. -., Hill, F. M., Schreiner, R., Ramalingam, R., Besselsen, D. G., Ghishan, F. K., & Kiela, P. R. (2011). High vitamin D-3 diet administered during active colitis negatively affects bone metabolism in an adoptive T cell transfer model. AMERICAN JOURNAL OF PHYSIOLOGY-GASTROINTESTINAL AND LIVER PHYSIOLOGY, 305(1), G35-G46.
• Larmonier, C. B., Midura-Kiela, M. T., Ramalingam, R., Laubitz, D., Janikashvili, N., Larmonier, N., Ghishan, F. K., & Kiela, P. R. (2011). Modulation of neutrophil motility by curcumin: implications for inflammatory bowel disease. Inflammatory bowel diseases, 17(2), 503-15.
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  Neutrophils (PMN) are the first cells recruited at the site of inflammation. They play a key role in the innate immune response by recognizing, ingesting, and eliminating pathogens and participate in the orientation of the adaptive immune responses. However, in inflammatory bowel disease (IBD) transepithelial neutrophil migration leads to an impaired epithelial barrier function, perpetuation of inflammation, and tissue destruction via oxidative and proteolytic damage. Curcumin (diferulolylmethane) displays a protective role in mouse models of IBD and in human ulcerative colitis, a phenomenon consistently accompanied by a reduced mucosal neutrophil infiltration.
• Oweis, S., Wu, L., Kiela, P., Zhao, H., Malhotra, D., Ghishan, F., Xie, Z., Shapiro, J., & Liu, J. (2011). Cardiac glycoside downregulates NHE3 activity and expression in LLC-PK1 cells. AMERICAN JOURNAL OF PHYSIOLOGY-RENAL PHYSIOLOGY, 290(5), F997-F1008.
• Bommireddy, R., Ramalingam, R., Midura-kiela, M. T., Larmonier, C. B., Kiela, P. R., Ghishan, F. K., & Bommireddy, R. (2010). 909 Lack of TGF-Beta Signaling in Dendritic Cells Leads to Systemic Autoimmunity. Gastroenterology, 138(5), S-129. doi:10.1016/s0016-5085(10)60594-x
• Kiela, P. R. (2010). Unraveling the pathophysiology of alcohol-induced thiamin deficiency. American journal of physiology. Renal physiology, 299(1), F26-7.
• Majewski, P. M., Thurston, R. D., Ramalingam, R., Kiela, P. R., & Ghishan, F. K. (2010). Cooperative Role of NF-kappa B and Poly(ADP-ribose) Polymerase 1 (PARP-1) in the TNF-induced Inhibition of PHEX Expression in Osteoblasts. JOURNAL OF BIOLOGICAL CHEMISTRY, 285(45), 34828-34838.
• Majewski, P. M., Thurston, R. D., Ramalingam, R., Kiela, P. R., & Ghishan, F. K. (2010). Cooperative role of NF-{kappa}B and poly(ADP-ribose) polymerase 1 (PARP-1) in the TNF-induced inhibition of PHEX expression in osteoblasts. The Journal of biological chemistry, 285(45), 34828-38.
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  Reduced bone mass is a common complication in chronic inflammatory diseases, although the mechanisms are not completely understood. The PHEX gene encodes a zinc endopeptidase expressed in osteoblasts and contributes to bone mineralization. The aim of this study was to determine the molecular mechanism involved in TNF-mediated down-regulation of Phex gene transcription. We demonstrate down-regulation of the Phex gene in two models of colitis: naive T-cell transfer and in gnotobiotic IL-10(-/-) mice. In vitro, TNF decreased expression of Phex in UMR106 cells and did not require de novo synthesis of a transrepressor. Transfecting UMR-106 cells with a series of deletion constructs of the proximal Phex promoter identified a region located within -74 nucleotides containing NF-κB and AP-1 binding sites. After TNF treatment, the RelA/p50 NF-κB complex interacted with two cis-elements at positions -70/-66 and -29/-25 nucleotides in the proximal Phex promoter. Inhibition of NF-κB signaling increased the basal level of Phex transcription and abrogated the effects of TNF, whereas overexpression of RelA mimicked the effect of TNF. We identified poly(ADP-ribose) polymerase 1 (PARP-1) binding immediately upstream of the NF-κB sites and showed that TNF induced poly(ADP-ribosyl)ation of RelA when bound to the Phex promoter. TNF-mediated Phex down-regulation was completely abrogated in vitro by PARP-1 inhibitor and overexpression of poly(ADP-ribose) glucohydrolase (PARG) and in vivo in PARP-1(-/-) mice. Our results suggest that NF-κB signaling and PARP-1 enzymatic activity cooperatively contribute to the constitutive and inducible suppression of Phex. The described phenomenon likely contributes to the loss of bone mass density in chronic inflammatory diseases, such as inflammatory bowel disease.
• Midura-kiela, M. T., Laubitz, D., Larmonier, C. B., Kiela, P. R., & Ghishan, F. K. (2010). Curcumin Inhibits IFN-{gamma} Signaling in Colonic Epithelial Cells. The FASEB Journal, 24.
• Navath, S., Rao, V., Woodford, R. T., Midura-Kiela, M. T., Ahad, A. M., Alleti, R., Kiela, P. R., & Mash, E. A. (2010). Design, Synthesis, and Testing of a Molecular Truck for Colonic Delivery of 5-Aminosalicylic Acid. ACS MEDICINAL CHEMISTRY LETTERS, 3(9), 710-714.
• PIERZYNOWSKI, S., ZABIELSKI, R., PODGURNIAK, P., KIELA, P., SHARMA, P., WESTROM, B., KATO, S., & BAREJ, W. (2010). EFFECTS OF REVERSIBLE COLD VAGAL BLOCKADE AND ATROPINIZATION ON EXOCRINE PANCREATIC FUNCTION DURING LIQUID FOOD-CONSUMPTION IN CALVES. JOURNAL OF ANIMAL PHYSIOLOGY AND ANIMAL NUTRITION-ZEITSCHRIFT FUR TIERPHYSIOLOGIE TIERERNAHRUNG UND FUTTERMITTELKUNDE, 67(5), 268-273.
• Thurston, R. D., Larmonier, C. B., Majewski, P. M., Ramalingam, R., Midura-Kiela, M., Laubitz, D., Vandewalle, A., Besselsen, D. G., Muehlbauer, M., Jobin, C., Kiela, P. R., & Ghishan, F. K. (2010). Tumor Necrosis Factor and Interferon-gamma Down-regulate Klotho in Mice With Colitis. GASTROENTEROLOGY, 138(4), 1384-U231.
• Thurston, R. D., Larmonier, C. B., Majewski, P. M., Ramalingam, R., Midura-Kiela, M., Laubitz, D., Vandewalle, A., Besselsen, D. G., Mühlbauer, M., Jobin, C., Kiela, P. R., & Ghishan, F. K. (2010). Tumor necrosis factor and interferon-gamma down-regulate Klotho in mice with colitis. Gastroenterology, 138(4), 1384-94, 1394.e1-2.
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  Klotho (KL) is an anti-inflammatory protein that protects the endothelium from nitric oxide (NO)-induced dysfunction, reduces the expression of endothelial adhesion molecules, and potentially regulates T-cell functions. KL deficiency leads to premature senescence and impaired Ca2+/Pi homeostasis, which can lead to inflammatory bowel disease (IBD)-associated osteopenia/osteoporosis. We investigated the changes in renal expression of Kl as a consequence of colitis.
• Zabielski, R., Lesniewska, ., Borlak, J., Gregory, P., Kiela, P., Pierzynowski, S., & Barej, W. (2010). Effects of intraduodenal administration of tarazepide on pancreatic secretion and duodenal EMG in neonatal calves. REGULATORY PEPTIDES, 78(1-3), 113-123.
• Kiela, P. R. (2009). Unraveling the pathophysiology of alcohol-induced thiamin deficiency. AMERICAN JOURNAL OF PHYSIOLOGY-RENAL PHYSIOLOGY, 299(1), F26-F27.
• Kiela, P. R., & Ghishan, F. K. (2009). Ion transport in the intestine. Current opinion in gastroenterology, 25(2), 87-91.
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  In recent years, the field of intestinal physiology has witnessed significant progress in our understanding of the expression and function of ion transport proteins and their genes under physiological and pathophysiological conditions. This review will present some of these most recent advances in the small intestinal ion transport mechanisms.
• Kiela, P. R., & Ghishan, F. K. (2009). Recent advances in the renal-skeletal-gut axis that controls phosphate homeostasis. Laboratory investigation; a journal of technical methods and pathology, 89(1), 7-14.
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  Under physiological conditions, homeostasis of inorganic phosphate (Pi) is tightly controlled by a network of increasingly more complex interactions and direct or indirect feedback loops among classical players, such as vitamin D (1,25(OH)2D3), parathyroid hormone (PTH), intestinal and renal phosphate transporters, and the recently described phosphatonins and minhibins. A series of checks and balances offsets the effects of 1,25(OH)2D3 and PTH to enable fine-tuning of intestinal and renal Pi absorptive capacity and bone resorption and mineralization. The latter include PHEX, FGF-23, MEPE, DMP1, and secreted FRP4. Despite this large number of regulatory components with complex interactions, the system has limited redundancy and is prone to dysregulation under pathophysiological conditions. This article reviews and synthesizes recent advances to present a new model of Pi homeostasis.
• Kiela, P. R., Laubitz, D., Larmonier, C. B., Midura-Kiela, M. T., Lipko, M. A., Janikashvili, N., Bai, A., Thurston, R., & Ghishan, F. K. (2009). Changes in mucosal homeostasis predispose NHE3 knockout mice to increased susceptibility to DSS-induced epithelial injury. Gastroenterology, 137(3), 965-75, 975.e1-10.
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  NHE3 is a target of inhibition by proinflammatory cytokines and pathogenic bacteria, an event contributing to diarrhea in infectious and idiopathic colitis. In mice, NHE3 deficiency leads to mild diarrhea, increased intestinal expression of interferon (IFN)-gamma, and distal colitis, suggesting its role in epithelial barrier homeostasis. Our aim was to investigate the role of NHE3 in maintaining mucosal integrity.
• Puchala, R., Zabielski, R., Lesniewska, ., Kiela, P., & Barej, W. (2009). Influence of duodenal infusion of L-methionine and L-methionine-dl-sulfoxide on amino acid concentration and duodenal electrical activity in Friesian calves. ANIMAL FEED SCIENCE AND TECHNOLOGY, 66(1-4), 75-84.
• Su, H. W., Wang, S. W., Ghishan, F. K., Kiela, P. R., & Tang, M. J. (2009). Cell confluency-induced Stat3 activation regulates NHE3 expression by recruiting Sp1 and Sp3 to the proximal NHE3 promoter region during epithelial dome formation. American journal of physiology. Cell physiology, 296(1), C13-24.
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  Activation of signal transducer and activator of transcription-3 (Stat3) during cell confluency is related to its regulatory roles in cell growth arrest- or survival-related physiological or developmental processes. We previously demonstrated that this signaling event triggers epithelial dome formation by transcriptional augmentation of sodium hydrogen exchanger-3 (NHE3) expression. However, the detailed molecular mechanism remained unclear. By using serial deletions, site-directed mutagenesis, and EMSA analysis, we now demonstrate Stat3 binding to an atypical Stat3-response element in the rat proximal NHE3 promoter, located adjacent to a cluster of Sp cis-elements (SpA/B/C), within -77/-36 nt of the gene. SpB (-58/-55 nt) site was more effective than SpA (-72/-69 nt) site for cooperative binding of Sp1/Sp3. Increasing cell density had no effect on Sp1/Sp3 expression but resulted in their increased binding to the SpA/B/C probe along with Stat3 and concurrently with enhanced nuclear pTyr705-Stat3 level. Immunoprecipitation performed with the nuclear extracts demonstrated physical interaction of Stat3 and Sp1/Sp3 triggered by cell confluency. Stat3 inhibition by overexpression of dominant-negative Stat3-D mutant in MDCK cells or by small interfering RNA-mediated knockdown in Caco-2 cells resulted in inhibition of the cell density-induced NHE3 expression, Sp1/Sp3 binding, and NHE3 promoter activity and in decreased dome formation. Thus, during confluency, ligand-independent Stat3 activation leads to its interaction with Sp1/Sp3, their recruitment to the SpA/B/C cluster in a Stat3 DNA-binding domain-dependent fashion, increased transcription, and expression of NHE3, to coordinate cell density-mediated epithelial dome formation.
• Xu, H., Collins, J., Bai, L., Kiela, P., Lynch, R., & Ghishan, F. (2009). Epidermal growth factor regulation of rat NHE2 gene expression. AMERICAN JOURNAL OF PHYSIOLOGY-CELL PHYSIOLOGY, 281(2), C504-C513.
• Ghishan, F. K., & Kiela, P. R. (2008). Epithelial Transport in Inflammatory Bowel Diseases. INFLAMMATORY BOWEL DISEASES, 20(6), 1099-1109.
• Kiela, P., Billerey-Larmonier, C., Uno, J. K., Larmonier, N., Midura, A. J., Timmermann, B., Ghishan, F. K., & Kiela, P. R. (2008). Protective effects of dietary curcumin in mouse model of chemically induced colitis are strain dependent. Inflammatory bowel diseases, 14(6).
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  Curcumin (diferulolylmethane) has been shown to have a protective role in mouse models of inflammatory bowel diseases (IBD) and to reduce the relapse rate in human ulcerative colitis (UC), thus making it a potentially viable supportive treatment option. Trinitrobenzene sulfonic acid (TNBS) colitis in NKT-deficient SJL/J mice has been described as Th1-mediated inflammation, whereas BALB/c mice are believed to exhibit a mixed Th1/Th2 response.
• Larmonier, C. B., Uno, J. K., Lee, K. M., Karrasch, T., Laubitz, D., Thurston, R., Midura-Kiela, M. T., Ghishan, F. K., Sartor, R. B., Jobin, C., & Kiela, P. R. (2008). Limited effects of dietary curcumin on Th-1 driven colitis in IL-10 deficient mice suggest an IL-10-dependent mechanism of protection. American journal of physiology. Gastrointestinal and liver physiology, 295(5), G1079-91.
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  Curcumin (diferulolylmethane) demonstrates profound anti-inflammatory effects in intestinal epithelial cells (IEC) and in immune cells in vitro and exhibits a protective role in rodent models of chemically induced colitis, with its presumed primary mechanism of action via inhibition of NF-kappaB. Although it has been demonstrated effective in reducing relapse rate in ulcerative colitis patients, curcumin's effectiveness in Crohn's disease (CD) or in Th-1/Th-17 mediated immune models of CD has not been evaluated. Therefore, we investigated the effects of dietary curcumin (0.1-1%) on the development of colitis, immune activation, and in vivo NF-kappaB activity in germ-free IL-10(-/-) or IL-10(-/-);NF-kappaB(EGFP) mice colonized with specific pathogen-free microflora. Proximal and distal colon morphology showed a mild protective effect of curcumin only at 0.1%. Colonic IFN-gamma and IL-12/23p40 mRNA expression followed similar pattern ( approximately 50% inhibition at 0.1%). Secretion of IL-12/23p40 and IFN-gamma by colonic explants and mesenteric lymph node cells was elevated in IL-10(-/-) mice and was not decreased by dietary curcumin. Surprisingly, activation of NF-kappaB in IL-10(-/-) mice (phospho-NF-kappaBp65) or in IL-10(-/-);NF-kappaB(EGFP) mice (whole organ or confocal imaging) was not noticeably inhibited by curcumin. Furthermore, we demonstrate that IL-10 and curcumin act synergistically to downregulate NF-kappaB activity in IEC and IL-12/23p40 production by splenocytes and dendritic cells. In conclusion, curcumin demonstrates limited effectiveness on Th-1 mediated colitis in IL-10(-/-) mice, with moderately improved colonic morphology, but with no significant effect on pathogenic T cell responses and in situ NF-kappaB activity. In vitro studies suggest that the protective effects of curcumin are IL-10 dependent.
• Laubitz, D., Larmonier, C. B., Bai, A., Midura-Kiela, M. T., Lipko, M. A., Thurston, R. D., Kiela, P. R., & Ghishan, F. K. (2008). Colonic gene expression profile in NHE3-deficient mice: evidence for spontaneous distal colitis. American journal of physiology. Gastrointestinal and liver physiology, 295(1), G63-G77.
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  Na+/H+ exchanger 3 (NHE3) provides a major route for intestinal Na+ absorption. NHE3 has been considered a target of proinflammatory cytokines and enteropathogenic bacteria, and impaired NHE3 expression and/or activity may be responsible for inflammation-associated diarrhea. However, the possibility of loss of NHE3 function reciprocally affecting gut immune homeostasis has not been investigated. In this report, we describe that NHE3-deficient mice spontaneously develop colitis restricted to distal colonic mucosa. NHE3(-/-) mice housed in a conventional facility exhibited phenotypic features such as mild diarrhea, occasional rectal prolapse, and reduced body weight. Genomewide microarray analysis identified not only a large group of transport genes that potentially represent an adaptive response, but also a considerable number of genes consistent with an inflammatory response. Histological examination demonstrated changes in the distal colon consistent with active inflammation, including crypt hyperplasia with an increased number of 5-bromo-2'-deoxyuridine-positive cells, diffuse neutrophilic infiltrate with concomitant 15-fold increase in matrix metalloproteinase 8 expression, an increased number of pSer276-RelA-positive cells, and a significant decrease in periodic acid-Schiff-positive goblet cells. Real-time PCR demonstrated elevated expression of inducible nitric oxide synthase (38-fold), TNF-alpha (6-fold), macrophage inflammatory protein-2 (48-fold), and IL-18 (3-fold) in the distal colon of NHE3(-/-) mice. NHE3(-/-) mice showed enhanced bacterial adhesion and translocation in the distal colon. Colitis was ameliorated by oral administration of broad-spectrum antibiotics. In conclusion, NHE3 deficiency leads to an exacerbated innate immune response, an observation suggesting a potentially novel role of NHE3 as a modifier gene, which when downregulated during infectious or chronic colitis may modulate the extent and severity of colonic inflammation.
• Su, H., Wang, S., Ghishan, F. K., Kiela, P. R., & Tang, M. (2008). Cell confluency-induced Stat3 activation regulates NHE3 expression by recruiting Sp1 and Sp3 to the proximal NHE3 promoter region during epithelial dome formation. AMERICAN JOURNAL OF PHYSIOLOGY-CELL PHYSIOLOGY, 296(1), C13-C24.
• Uno, J. K., Thurston, R. D., Midura-kiela, M. T., Larmonier, C. B., Kiela, P. R., & Ghishan, F. K. (2008). Downregulation of Klotho in Experimental Colitis: the Role of TNFα and IFN-γ. Gastroenterology, 134(4), A-145. doi:10.1016/s0016-5085(08)60676-9
• Arima, K., Hines, E., Kiela, P., Drees, J., Collins, J., & Ghishan, F. (2007). Glucocorticoid regulation and glycosylation of mouse intestinal type IIb Na-P-i cotransporter during ontogeny. AMERICAN JOURNAL OF PHYSIOLOGY-GASTROINTESTINAL AND LIVER PHYSIOLOGY, 283(2), G426-G434.
• Hines, E., Kolek, O., Jones, M., Serey, S., Sirjani, N., Kiela, P., Jurutka, P., Haussler, M., Collins, J., & Ghishan, F. (2007). 1,25-dihydroxyvitamin D-3 down-regulation of PHEX gene expression is mediated by apparent repression of a 110 kDa transfactor that binds to a polyadenine element in the promoter. JOURNAL OF BIOLOGICAL CHEMISTRY, 279(45), 46406-46414.
• Hua, P., Xu, H., Uno, J. K., Lipko, M. A., Dong, J., Kiela, P. R., & Ghishan, F. K. (2007). Sp1 and Sp3 mediate NHE2 gene transcription in the intestinal epithelial cells. American journal of physiology. Gastrointestinal and liver physiology, 293(1), G146-53.
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  Our previous studies have identified a minimal Sp1-driven promoter region (nt -36/+116) directing NHE2 expression in mouse renal epithelial cells. However, this minimal promoter region was not sufficient to support active transcription of NHE2 gene in the intestinal epithelial cells, suggesting the need for additional upstream regulatory elements. In the present study, we used nontransformed rat intestinal epithelial (RIE) cells as a model to identify the minimal promoter region and transcription factors necessary for the basal transcription of rat NHE2 gene in the intestinal epithelial cells. We identified a region within the rat NHE2 gene promoter located within nt -67/-43 upstream of transcription initiation site as indispensable for the promoter function in intestinal epithelial cells. Mutations at nt -56/-51 not only abolished the DNA-protein interaction in this region, but also completely abolished NHE2 gene promoter activity in RIE cells. Supershift assays revealed that Sp1 and Sp3 interact with this promoter region, but, contrary to the minimal promoter indispensable for renal expression of NHE2, both transcription factors expressed individually in Drosophila SL2 cells activated rat NHE2 gene promoter. Moreover, Sp1 was a weaker transactivator and when coexpressed in SL2 cells it reduced Sp3-mediated NHE2 basal promoter activity. Furthermore, DNase I footprinting confirmed that nt -58/-51 is protected by nuclear protein from RIE cells. We conclude that the mechanism of basal control of rat NHE2 gene promoter activity is different in the renal and intestinal epithelium, with Sp3 being the major transcriptional activator of NHE2 gene transcription in the intestinal epithelial cells.
• Kiela, P. R., Kuscuoglu, N., Midura, A. J., Midura-Kiela, M. T., Larmonier, C. B., Lipko, M., & Ghishan, F. K. (2007). Molecular mechanism of rat NHE3 gene promoter regulation by sodium butyrate. American journal of physiology. Cell physiology, 293(1), C64-74.
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  Sodium butyrate (NaB) stimulates sodium and water absorption by inducing colonic Na(+)/H(+) exchange. NaB induces Na(+)/H(+) exchanger (NHE)3 activity and protein and mRNA expression both in vivo and in vitro. Our previously published observations indicated that this induction is Ser/Thr kinase dependent and that NaB-responsive elements were localized within -320/-34 bp of the rat NHE3 promoter. Here we further delineate the mechanism of NaB-mediated NHE3 gene transcription. Transient and stable transfection of Caco-2 cells with NHE3 gene reporter constructs identified Sp binding site SpB at position -58/-55 nt as critical for NaB-mediated induction. Gel mobility shift (GMSA) and DNA affinity precipitation assays indicated NaB-induced binding of Sp3 and decreased binding of Sp1 to SpB element. While no changes in expression of Sp1 or Sp3 were noted, NaB induced phosphorylation of Sp1 and acetylation of Sp3. Sp3 was a more potent inducer of NHE3 gene transcription, which suggested that change in balance, favoring binding of Sp3 to the SpB site, would result in significant increase in NHE3 promoter activity. Small interfering RNA studies in Caco-2 cells and data from NaB-treated SL2 cells used as a reconstitution model confirmed this hypothesis. In addition to the SpB site, which played a permissive role, an upstream novel butyrate response element located at -196/-175 nt was necessary for maximal induction. GMSA identified a protein-DNA complex with a -196/-175 nt probe; this interaction was not affected by NaB treatment, thus suggesting that in response to NaB Sp3 binding to site SpB precedes and results in recruitment of the putative factor to this upstream site.
• Larmonier, C. B., Midura-Kiela, M. T., Ramalingam, R., Laubitz, D., Janikashvili, N., Larmonier, N., Ghishan, F. K., & Kiela, P. R. (2007). Modulation of Neutrophil Motility by Curcumin: Implications for Inflammatory Bowel Disease. INFLAMMATORY BOWEL DISEASES, 17(2), 503-515.
• Su, H. W., Yeh, H. H., Wang, S. W., Shen, M. R., Chen, T. L., Kiela, P. R., Ghishan, F. K., & Tang, M. J. (2007). Cell confluence-induced activation of signal transducer and activator of transcription-3 (Stat3) triggers epithelial dome formation via augmentation of sodium hydrogen exchanger-3 (NHE3) expression. The Journal of biological chemistry, 282(13), 9883-94.
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  Cell confluence induces the activation of signal transducer and activator of transcription-3 (Stat3) in various cancer and epithelial cells, yet the biological implications and the associated regulatory mechanisms remain unclear. Because confluent polarized epithelia demonstrate dome formation and sodium influx that mimic the onset of differentiation, we sought to elucidate the role of Stat3 in association with the regulation of selective epithelial transporters in this biological phenomenon. This study established the correlation between Stat3 activation and cell confluence-induced dome formation in Madin-Darby canine kidney cells (MDCK) by following Stat3 activation events in dome-forming cells. Epifluorescent and confocal microscopy provided evidence showing specific localization of phosphorylated Stat3 Tyr(705) in the nuclei of dome-forming cells at initial stages. The relationship was further elucidated by the establishment of tetracycline-inducible expression of constitutive Stat3 mutant (Stat3-C) in MDCK cells or expression of dominant negative Stat3 (Stat3-D) stable cell lines (MDCK and NMuMG). Dome formation was promoted by the expression of Stat3-C but inhibited by Stat3-D. Two trans-epithelial transporters, NHE3 and ENaC alpha-subunit, were found to be increased during cell confluence. Interestingly, NHE3 expression could be specifically up-regulated by Stat3-C but inhibited by Stat3-D through promoter regulation, whereas NHE1 and ENaC alpha-subunit were not affected by Stat3 expression. Application of NHE3 shRNA, NHE3 inhibitors (EIPA and S3226) suppressed confluence-induced dome formation in MDCK or NMuMG cells. These results demonstrate a cell confluence-induced Stat3 signaling pathway in epithelial cells in triggering dome formation through NHE3 augmentation.
• Funk, J. L., Frye, J. B., Oyarzo, J. N., Kuscuoglu, N., Wilson, J., McCaffrey, G., Stafford, G., Chen, G., Lantz, R. C., Jolad, S. D., Sólyom, A. M., Kiela, P. R., & Timmermann, B. N. (2006). Efficacy and mechanism of action of turmeric supplements in the treatment of experimental arthritis. Arthritis and rheumatism, 54(11), 3452-64.
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  Scientific evidence is lacking for the antiarthritic efficacy of turmeric dietary supplements that are being promoted for arthritis treatment. Therefore, we undertook studies to determine the antiarthritic efficacy and mechanism of action of a well-characterized turmeric extract using an animal model of rheumatoid arthritis (RA).
• Kiela, P. R., Xu, H., & Ghishan, F. K. (2006). Apical NA+/H+ exchangers in the mammalian gastrointestinal tract. Journal of physiology and pharmacology : an official journal of the Polish Physiological Society, 57 Suppl 7, 51-79.
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  The Slc9a family of nine Na(+)/H(+) exchangers (NHE) plays a critical role in neutral sodium absorption in the mammalian intestine as well as other absorptive and secretory epithelia of digestive organs. These transport proteins mediate the electroneutral exchange of Na(+) and H(+) and are crucial in a variety of physiological processes, including the fine tuning of intracellular pH, cell volume control and systemic electrolyte, acid-base and fluid volume homeostasis. Here, we review the role of the Na(+)/H(+) exchange mechanism as it relates to the physiology of organs and cells involved in nutrient absorption, and we describe physiological and molecular aspects of individual isoforms, including their structure, tissue-, and subcellular distribution, as well as their regulation by physiological stimuli at the transcriptional and post-transcriptional levels. A particular emphasis is placed on Na(+)/H(+) exchanger isoforms expressed on the apical (brush border) membrane of the epithelial cells, and the consequences of gene-targeted mutation of individual isoforms are discussed in the context of the physiology of digestive organs. Where available, we also provide a review of pathophysiological states related to aberrant expression and/or activity of Na(+)/H(+) exchangers within the confines of the digestive system.
• Kolek, O., Hines, E., Jones, M., LeSueur, L., Lipko, M., Kiela, P., Collins, J., Haussler, M., & Ghishan, F. (2006). 1 alpha,25-Dihydroxyvitamin D-3 upregulates FGF23 gene expression in bone: the final link in a renal-gastrointestinal-skeletal axis that controls phosphate transport. AMERICAN JOURNAL OF PHYSIOLOGY-GASTROINTESTINAL AND LIVER PHYSIOLOGY, 289(6), G1036-G1042.
• Larmonier, C. B., Laubitz, D., Thurston, R. D., Bucknam, A. L., Hill, F. M., Midura-Kiela, M., Ramalingam, R., Kiela, P. R., & Ghishan, F. K. (2006). NHE3 modulates the severity of colitis in IL-10-deficient mice. AMERICAN JOURNAL OF PHYSIOLOGY-GASTROINTESTINAL AND LIVER PHYSIOLOGY, 300(6), G998-G1009.
• Oweis, S., Wu, L., Kiela, P. R., Zhao, H., Malhotra, D., Ghishan, F. K., Xie, Z., Shapiro, J. I., & Liu, J. (2006). Cardiac glycoside downregulates NHE3 activity and expression in LLC-PK1 cells. American journal of physiology. Renal physiology, 290(5), F997-1008.
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  Ouabain, a cardiotonic steroid and a specific inhibitor of the Na(+)-K(+)-ATPase, has been shown to significantly inhibit transcellular Na(+) transport without altering the intracellular Na(+) concentration ([Na(+)](i)) in the epithelial cells derived from the renal proximal tubules. We therefore studied whether ouabain affects the activity and expression of Na(+)/H(+) exchanger isoform 3 (NHE3) representing the major route of apical Na(+) reabsorption in LLC-PK(1) cells. Chronic basolateral, but not apical, exposure to low-concentration ouabain (50 and 100 nM) did not change [Na(+)](i) but significantly reduced NHE3 activity, NHE3 protein, and mRNA expression. Inhibition of c-Src or phosphoinositide 3-kinase (PI3K) with PP2 or wortmannin, respectively, abolished ouabain-induced downregulation of NHE3 activity and mRNA expression. In caveolin-1 knockdown LLC-PK(1) cells, ouabain failed to downregulate NHE3 mRNA expression and NHE3 promoter activity. Ouabain response elements were mapped to a region between -450 and -1,194 nt, where decreased binding of thyroid hormone receptor (TR) and Sp1 to their cognate cis-elements was documented in vitro and in vivo by protein/DNA array analysis, EMSA, supershift, and chromatin immunoprecipitation. These data suggest that, in LLC-PK(1) cells, ouabain-induced signaling through the Na(+)-K(+)-ATPase-Src pathway results in decreased Sp1 and TR DNA binding activity and consequently in decreased expression and activity of NHE3. These novel findings may represent the underlying mechanism of cardiotonic steroid-mediated renal compensatory response to volume expansion and/or hypertension.
• Radhakrishnan, V. M., Kojs, P., Young, G., Ramalingam, R., Jagadish, B., Mash, E. A., Martinez, J. D., Ghishan, F. K., & Kiela, P. R. (2006). pTyr(421) Cortactin Is Overexpressed in Colon Cancer and Is Dephosphorylated by Curcumin: Involvement of Non-Receptor Type 1 Protein Tyrosine Phosphatase (PTPN1). PLOS ONE, 9(1).
• Ramalingam, R., Larmonier, C. B., Thurston, R. D., Midura-Kiela, M. T., Zheng, S. G., Ghishan, F. K., & Kiela, P. R. (2006). Dendritic Cell-Specific Disruption of TGF-beta Receptor II Leads to Altered Regulatory T Cell Phenotype and Spontaneous Multiorgan Autoimmunity. JOURNAL OF IMMUNOLOGY, 189(8), 3878-3893.
• Uno, J. K., Kolek, O. I., Hines, E. R., Xu, H., Timmermann, B. N., Kiela, P. R., & Ghishan, F. K. (2006). The role of tumor necrosis factor alpha in down-regulation of osteoblast Phex gene expression in experimental murine colitis. Gastroenterology, 131(2), 497-509.
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  Reduced bone mass is a common complication of inflammatory bowel disease (IBD), although the mechanisms that contribute to osteopenia are not completely understood. Tumor necrosis factor alpha (TNF-alpha) is up-regulated in patients with IBD and has detrimental effects on osteoblasts. Phex gene is expressed predominantly in osteoblasts, and its disruption results in defective bone mineralization. The aim of this study was to evaluate whether TNF-alpha regulates Phex gene expression thus contributing to the abnormal bone metabolism observed in IBD.
• Xu, H., Xu, H., Uno, J. K., Kolek, O. I., Kiela, P. R., Ghishan, F. K., & Feferman, H. R. (2006). The Role of TNF{alpha} in Down-Regulation of Osteoblast Phex Gene Expression in Experimental Colitis. The FASEB Journal, 20(5).
• Xu, L., Dixit, M. P., Nullmeyer, K. D., Xu, H., Kiela, P. R., Lynch, R. M., & Ghishan, F. K. (2006). Regulation of Na+/H+ exchanger-NHE3 by angiotensin-II in OKP cells. Biochimica et biophysica acta, 1758(4), 519-26.
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  Previous studies have shown that circulating Angiotensin II (A-II) increases renal Na+ reabsorption via elevated Na+/H+ exchanger isoform 3 (NHE3) activity. We hypothesized that prolonged exposure to A-II leads to an increased expression of renal NHE3 by a transcriptionally mediated mechanism. To test this hypothesis, we utilized the proximal tubule-like OKP cell line to evaluate the effects of 16-h treatment with A-II on NHE3 activity and gene expression. A-II significantly stimulated NHE3-mediated, S-3226-sensitive Na+/H+ exchange. Inhibition of transcription with actinomycin D abolished the stimulatory effect of A-II on NHE3-mediated pH recovery in acid-loaded OKP cells. This prolonged exposure to A-II was also found to elevate endogenous NHE3 mRNA (by 40%)-an effect also abolished by inhibition of gene transcription. To evaluate the molecular mechanism by which A-II regulates NHE3 expression, the activity of NHE3 promoter driven reporter gene was analyzed in transient transfection assays. In transfected OKP cells, rat NHE3 promoter activity was significantly stimulated by A-II treatment, and preliminary mapping indicated that the A-II responsive element(s) is present between 149 and 548 bp upstream of the transcription initiation site in the NHE3 gene promoter. We conclude that a transcriptional mechanism is at least partially responsible for the chronic effects of A-II treatment on renal NHE3 activity.
• Kiela, P. R., Midura, A. J., Kuscuoglu, N., Jolad, S. D., Sólyom, A. M., Besselsen, D. G., Timmermann, B. N., & Ghishan, F. K. (2005). Effects of Boswellia serrata in mouse models of chemically induced colitis. American journal of physiology. Gastrointestinal and liver physiology, 288(4), G798-808.
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  Extracts from Boswellia serrata have been reported to have anti-inflammatory activity, primarily via boswellic acid-mediated inhibition of leukotriene synthesis. In three small clinical trials, boswellia was shown to improve symptoms of ulcerative colitis and Crohn's disease, and because of its alleged safety, boswellia was considered superior over mesalazine in terms of a benefit-risk evaluation. The goal of this study was to evaluate the effectiveness of boswellia extracts in controlled settings of dextran sulfate- or trinitrobenzene sulfonic acid-induced colitis in mice. Our results suggest that boswellia is ineffective in ameliorating colitis in these models. Moreover, individual boswellic acids were demonstrated to increase the basal and IL-1beta-stimulated NF-kappaB activity in intestinal epithelial cells in vitro as well as reverse proliferative effects of IL-1beta. We also observed hepatotoxic effect of boswellia with pronounced hepatomegaly and steatosis. Hepatotoxity and increased lipid accumulation in response to boswellia were further confirmed in vitro in HepG2 cells with fluorescent Nile red binding/resazurin reduction assay and by confocal microscopy. Microarray analyses of hepatic gene expression demonstrated dysregulation of a number of genes, including a large group of lipid metabolism-related genes, and detoxifying enzymes, a response consistent with that to hepatotoxic xenobiotics. In summary, boswellia does not ameliorate symptoms of colitis in chemically induced murine models and, in higher doses, may become hepatotoxic. Potential implications of prolonged and uncontrolled intake of boswellia as an herbal supplement in inflammatory bowel disease and other inflammatory conditions should be considered in future clinical trials with this botanical.
• Kiela, P., Zabielski, R., Podgurniak, P., Midura, M., Barej, W., Gregory, P., & Pierzynowski, S. (2005). Cholecystokinin-8 and vasoactive intestinal polypeptide stimulate exocrine pancreatic secretion via duodenally mediated mechanisms in the conscious pig. EXPERIMENTAL PHYSIOLOGY, 81(3), 375-384.
• Kolek, O. I., Hines, E. R., Jones, M. D., LeSueur, L. K., Lipko, M. A., Kiela, P. R., Collins, J. F., Haussler, M. R., & Ghishan, F. K. (2005). 1alpha,25-Dihydroxyvitamin D3 upregulates FGF23 gene expression in bone: the final link in a renal-gastrointestinal-skeletal axis that controls phosphate transport. American journal of physiology. Gastrointestinal and liver physiology, 289(6), G1036-42.
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  Fibroblast growth factor (FGF)23 is a phosphaturic hormone that decreases circulating 1alpha,25-dihydroxyvitamin D(3) [1,25(OH)(2)D(3)] and elicits hypophosphatemia, both of which contribute to rickets/osteomalacia. It has been shown recently that serum FGF23 increases after treatment with renal 1,25(OH)(2)D(3) hormone, suggesting that 1,25(OH)(2)D(3) negatively feedback controls its levels by inducing FGF23. To establish the tissue of origin and the molecular mechanism by which 1,25(OH)(2)D(3) increases circulating FGF23, we administered 1,25(OH)(2)D(3) to C57BL/6 mice. Within 24 h, these mice displayed a dramatic elevation in serum immunoreactive FGF23, and the expression of FGF23 mRNA in bone was significantly upregulated by 1,25(OH)(2)D(3), but there was no effect in several other tissues. Furthermore, we treated rat UMR-106 osteoblast-like cells with 1,25(OH)(2)D(3), and real-time PCR analysis revealed a dose- and time-dependent stimulation of FGF23 mRNA concentrations. The maximum increase in FGF23 mRNA was 1,024-fold at 10(-7) M 1,25(OH)(2)D(3) after 24-h treatment, but statistically significant differences were observed as early as 4 h after 1,25(OH)(2)D(3) treatment. In addition, using cotreatment with actinomycin D or cycloheximide, we observed that 1,25(OH)(2)D(3) regulation of FGF23 gene expression occurs at the transcriptional level, likely via the nuclear vitamin D receptor, and is dependent on synthesis of an intermediary transfactor. These results indicate that bone is a major site of FGF23 expression and source of circulating FGF23 after 1,25(OH)(2)D(3) administration or physiological upregulation. Our data also establish FGF23 induction by 1,25(OH)(2)D(3) in osteoblasts as a feedback loop between these two hormones that completes a kidney-intestine-bone axis that mediates phosphate homeostasis.
• Lan, Q., Zhou, X., Fan, H., Chen, M., Wang, J., Ryffel, B., Brand, D., Ramalingam, R., Kiela, P. R., Horwitz, D. A., Liu, Z., & Zheng, S. G. (2005). Polyclonal CD4Foxp3 Treg cells induce TGF beta-dependent tolerogenic dendritic cells that suppress the murine lupus-like syndrome. JOURNAL OF MOLECULAR CELL BIOLOGY, 4(6), 409-419.
• PIERZYNOWSKI, S., ERLANSONALBERTSSON, C., PODGURNIAK, P., KIELA, P., & WESTROM, B. (2005). POSSIBLE INTEGRATION OF THE ELECTRICAL-ACTIVITY OF THE DUODENUM AND PANCREAS SECRETION THROUGH ENTEROSTATIN. BIOMEDICAL RESEARCH-TOKYO, 15, 257-260.
• Su, H., Yeh, H., Wang, S., Shen, M., Chen, T., Kiela, P. R., Ghishan, F. K., & Tang, M. (2005). Cell confluence-induced activation of signal transducer and activator of transcription-3 (Stat3) triggers epithelial dome formation via augmentation of sodium hydrogen exchanger-3 (NHE3) expression. JOURNAL OF BIOLOGICAL CHEMISTRY, 282(13), 9883-9894.
• Zabielski, R., Kiela, P., Onaga, T., Mineo, H., Gregory, P., & Kato, S. (2005). Effect of neural blockades, gastrointestinal regulatory peptides, and diversion of gastroduodenal contents on periodic pancreatic secretion in the preruminant calf. CANADIAN JOURNAL OF PHYSIOLOGY AND PHARMACOLOGY, 73(11), 1616-1624.
• Hines, E. R., Kolek, O. I., Jones, M. D., Serey, S. H., Sirjani, N. B., Kiela, P. R., Jurutka, P. W., Haussler, M. R., Collins, J. F., & Ghishan, F. K. (2004). 1,25-dihydroxyvitamin D3 down-regulation of PHEX gene expression is mediated by apparent repression of a 110 kDa transfactor that binds to a polyadenine element in the promoter. The Journal of biological chemistry, 279(45), 46406-14.
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  The PHEX gene encodes an endopeptidase expressed in osteoblasts that inactivates an uncharacterized peptide hormone, phosphatonin, which suppresses bone mineralization as well as renal phosphate reabsorption and vitamin D bioactivation. We demonstrate that 1alpha-25-dihydroxyvitamin D (1,25(OH)2D3), the, active renal vitamin D metabolite, decreases PHEX mRNA in the rat osteoblastic cell line, UMR-106, as well as in mouse calvaria. Promoter/reporter construct analysis of the murine PHEX gene in transfected UMR-106 cells localized the repressive effect of 1,25(OH)2D3 to the -133 to -74 bp region, and gel mobility shift experiments revealed that 1,25(OH)2D3 treatment of the cells diminished the binding of a nuclear protein(s) to a stretch of 17 adenines from bp -116 to -100 in the proximal PHEX promoter. Either overexpression of a dominant-negative vitamin D receptor (VDR) or deletion of this sequence of 17 A-T base pairs abolished the repressive effect of 1,25(OH)2D3 by attenuating basal promoter activity, indicating that this region mediates the 1,25(OH)2D3 response and is involved in basal transcription. South-western blot analysis and DNA affinity purification show that an unidentified 110 kDa nuclear protein binds to the poly(A) element. Because 1,25(OH)2D3-liganded VDR neither binds to the polyadenine region of the PHEX promoter nor directly influences the association of the 110 kDa transfactor, we conclude that 1,25(OH)2D3 indirectly decreases PHEX expression via VDR-mediated repression (or modification) of this novel transactivator. Thus, we have identified a cis-element required for PHEX gene transcription that participates in negative feedback control of PHEX expression and thereby modulates the actions of phosphatonin.
• Jiang, L., Wang, J., Solorzano-Vargas, R. S., Tsai, H. V., Gutierrez, E. M., Ontiveros, L. O., Kiela, P. R., Wu, S. V., & Martín, M. G. (2004). Characterization of the rat intestinal Fc receptor (FcRn) promoter: transcriptional regulation of FcRn gene by the Sp family of transcription factors. American journal of physiology. Gastrointestinal and liver physiology, 286(6), G922-31.
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  The regulatory elements that control the transcriptional regulation of the intestinal Fc receptor (FcRn) have not been elucidated. The objective of this study was to characterize the core promoter region of the rat FcRn gene. Chimeric clones that contained various regions of the promoter located upstream of the luciferase reporter were transiently transfected into either IEC-6 or Caco-2 cell lines and nuclear extracts were used to perform DNase I footprint and DNA binding assays (EMSA). Transfection of chimeric upstream nested deletions-luciferase reporter clones into either of these cell lines supported robust reporter activity and identified the location of the minimal promoter at -157/+135. DNase I footprint analysis revealed two complexes located within the gene's core promoter region, and site-directed mutagenesis identified two regions that were critical to maintain basal expression. EMSA identified the presence of five Sp elements within the immediate promoter region that are capable of binding members of the Sp family of proteins. Among the five Sp elements, one element appears to not bind Sp1, Sp2, or Sp3 while influencing the interaction of Sp proteins with an adjacent Sp site. Overexpression of either Sp1 or Sp3 augments activity of the minimal promoter in Sp-deficient Drosophila SL2 cells. In summary, we report on the characterization of the rat FcRn minimal promoter, including the characterization of five Sp elements within this region that interact with members of the Sp family of transcriptional factors and drive promoter activity in intestinal cell lines.
• Kiela, P. R., & Ghishan, F. K. (2004). Ion transport in the intestine. CURRENT OPINION IN GASTROENTEROLOGY, 25(2), 87-91.
• Kiela, P., Hines, E., Collins, J., & Ghishan, F. (2004). Regulation of the rat NHE3 gene promoter by sodium butyrate. AMERICAN JOURNAL OF PHYSIOLOGY-GASTROINTESTINAL AND LIVER PHYSIOLOGY, 281(4), G947-G956.
• Kiela, P. R., LeSueur, J., Collins, J. F., & Ghishan, F. K. (2003). Transcriptional regulation of the rat NHE3 gene. Functional interactions between GATA-5 and Sp family transcription factors. The Journal of biological chemistry, 278(8), 5659-68.
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  Expression of sodium-hydrogen exchanger isoform 3 (NHE3) in the intestinal and renal epithelium plays a critical role in sodium absorption and acid/base homeostasis. To decipher rat NHE3 gene regulation, its cis-acting regulatory elements and associated transcription factors were characterized by transient transfection of Caco-2, IEC-6, Qt6, and Drosophila SL2 cells. Deletion and mutational analyses demonstrated that the atypical TATA box located at bp -26/-31 was not necessary for promoter activity, and that a -20/+8-bp fragment represents a functional initiator. Within the 81-bp upstream region, three Sp transcription factor binding sites were critical because their mutation drastically reduced promoter activity. The roles of Sp1 and Sp3 were further demonstrated by electromobility shift assay and by transactivation of the NHE3 promoter in SL2 cells by forced expression of Sp1 and Sp3. Both of these transcription factors were found to act synergistically with GATA-5 bound to a GATA box in exon 1 (+20/+23 bp). These studies demonstrate that rat NHE3 promoter is initiator-driven and controlled mainly by Sp1 and Sp3, which functionally interact with GATA-5. This interaction represents a novel regulatory mechanism, which is likely to participate in a gradient of intestinal gene expression along the crypt-villus axis.
• Kruszewska, D., Kiela, P., Ljungh, A., Erlwanger, K. H., Weström, B. R., Linderoth, A., & Pierzynowski, S. G. (2003). Enteral crude red kidney bean (Phaseolus vulgaris) lectin--phytohemagglutinin--induces maturational changes in the enterocyte membrane proteins of suckling rats. Biology of the neonate, 84(2), 152-8.
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  This study aimed to investigate the effect of enterally administered crude red kidney bean (Phaseolus vulgaris) lectin, PHA, on the expression of brush-border membrane vesicle (BBMV) proteins, in particular Na(+)/H(+) exchangers (NHEs), in the small intestine of suckling rats. Gavage of PHA to 14-day-old rats for 3 days resulted in altered protein/glycoprotein patterns as analyzed by SDS-PAGE. Immunoblots demonstrated the appearance of two 71- and 27-kD protein bands indicative for NHE3--one of the NHE isoforms--and PHA, respectively. PHA treatment also resulted in an augmented uptake of (22)Na(+) by the BBMV indicating an increase in NHE activity. Overall, the data suggests that enteral PHA exposure may induce maturational changes in enterocyte membrane proteins in young rats. In view of these findings, an investigation into the addition of PHA to infant formulas and weaning diets is warranted.
• Laubitz, D., Larmonier, C. B., Bai, A., Midura-Kiela, M. T., Lipko, M. A., Thurston, R. D., Kiela, P. R., & Ghishan, F. K. (2003). Colonic gene expression profile in NHE3-deficient mice: evidence for spontaneous distal colitis. AMERICAN JOURNAL OF PHYSIOLOGY-GASTROINTESTINAL AND LIVER PHYSIOLOGY, 295(1), G63-G77.
• Arima, K., Hines, E. R., Kiela, P. R., Drees, J. B., Collins, J. F., & Ghishan, F. K. (2002). Glucocorticoid regulation and glycosylation of mouse intestinal type IIb Na-P(i) cotransporter during ontogeny. American journal of physiology. Gastrointestinal and liver physiology, 283(2), G426-34.
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  We sought to characterize expression of an apically expressed intestinal Na-P(i) cotransporter (Na-P(i)-IIb) during mouse ontogeny and to assess the effects of methylprednisolone (MP) treatment. In control mice, Na-P(i) uptake by intestinal brush-border membrane vesicles was highest at 14 days of age, lower at 21 days, and further reduced at 8 wk and 8-9 mo of age. Na-P(i)-IIb mRNA and immunoreactive protein levels in 14-day-old animals were markedly higher than in older groups. MP treatment significantly decreased Na-P(i) uptake and Na-P(i)-IIb mRNA and protein expression in 14-day-old mice. Additionally, the size of the protein was smaller in 14-day-old mice. Deglycosylation of protein from 14-day-old and 8-wk-old animals with peptide N-glycosidase reduced the molecular weight to the predicted size. We conclude that intestinal Na-P(i) uptake and Na-P(i)-IIb expression are highest at 14 days and decrease with age. Furthermore, MP treatment reduced intestinal Na-P(i) uptake approximately threefold in 14-day-old mice and this reduction correlates with reduced Na-P(i)-IIb mRNA and protein expression. We also demonstrate that Na-P(i)-IIb is an N-linked glycoprotein and that glycosylation is age dependent.
• Erickson, R. P., Kiela, M., Devine, P. J., Hoyer, P. B., & Heidenreich, R. A. (2002). mdr1a deficiency corrects sterility in Niemann-Pick C1 protein deficient female mice. Molecular reproduction and development, 62(2), 167-73.
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  Niemann-Pick type C disease is a progressive neurological disease with cholesterol storage in liver, and npc1-/- mice share these features and are sterile. We have searched for the cause of sterility and found normal folliculogenesis and progesterone levels but lack of implantation. Multiple drug resistance (MDR) P-glycoproteins are plasma membrane proteins implicated in the movement of drugs and lipids across membranes. Their functions are inhibited by progesterone, which has been shown to alter cellular cholesterol homeostasis and has implicated P-glycoproteins in the movement of cholesterol to the endoplasmic reticulum. We have introduced the mdr1a knockout into the npc1 mutant line. While the neurological disease continues at its usual rate, preventing the females from taking care of their litters, npc1-/-, mdr1a-/- females became fertile. Although the mdr1a P-glycoprotein co-localizes with caveolae, neither caveolin-1 nor npc1 levels were significantly altered in the livers of double homozygotes. The absence of mdr1a was confirmed by immunoblotting, but npc1 deficiency was not associated with consistent changes in cerebellar mdr1a in mdr1a+/+ mice. The results show that a mdr1a mutation is an in vivo suppressor of female sterility in npc1 deficient mice.
• Kiela, P. R., Hines, E. R., Collins, J. F., & Ghishan, F. K. (2001). Regulation of the rat NHE3 gene promoter by sodium butyrate. American journal of physiology. Gastrointestinal and liver physiology, 281(4), G947-56.
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  Short-chain fatty acids, and especially butyrate (NaB), stimulate sodium and water absorption by inducing colonic Na+/H+ exchange (NHE). NaB induces NHE3 activity and protein and mRNA expression both in vivo and in vitro. NaB, as a histone deacetylase (HDAC) inhibitor, regulates gene transcription. We therefore studied whether NaB regulates transcription of the rat NHE3 promoter in transiently transfected Caco-2 cells. NaB (5 mM) strongly stimulated reporter gene activity, and this stimulation was prevented with actinomycin D, indicating transcriptional activation. NaB effects on the NHE3 promoter depended on the activity of Ser/Thr kinases, in particular, protein kinase A (PKA). However, PKA stimulation alone did not have an effect on promoter activity, and it did not act synergistically with NaB. Another HDAC inhibitor, Trichostatin A (TSA), stimulated NHE3 promoter in a Ser/Thr kinase-independent fashion. The putative NaB-responsive elements were localized within -320/-34 bp of the NHE3 promoter. These findings suggest that PKA mediates NaB effects on NHE3 gene transcription and that the mechanism of NaB action is different from that of TSA.
• Kiela, P. R., Laubitz, D., Larmonier, C. B., Midura-Kiela, M. T., Lipko, M. A., Janikashvili, N., Bai, A., Thurston, R., & Ghishan, F. K. (2001). Changes in Mucosal Homeostasis Predispose NHE3 Knockout Mice to Increased Susceptibility to DSS-Induced Epithelial Injury. GASTROENTEROLOGY, 137(3), 965-975.
• Kiela, P. R., Xu, H., & Ghishan, F. K. (2001). APICAL NA(+)/H(+) EXCHANGERS IN THE MAMMALIAN GASTROINTESTINAL TRACT. JOURNAL OF PHYSIOLOGY AND PHARMACOLOGY, 57, 51-79.
• Xu, H., Collins, J. F., Bai, L., Kiela, P. R., & Ghishan, F. K. (2001). Regulation of the human sodium-phosphate cotransporter NaP(i)-IIb gene promoter by epidermal growth factor. American journal of physiology. Cell physiology, 280(3), C628-36.
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  The intestinal sodium-phosphate cotransporter (NaP(i)-IIb) plays a major role in intestinal P(i) absorption. Epidermal growth factor (EGF) is involved in the regulation of P(i) homeostasis. However, the role of EGF in intestinal NaP(i)-IIb regulation is not clear. The current studies showed that EGF decreased NaP(i)-IIb mRNA abundance by 40-50% in both rat intestine and Caco-2 cells. To understand the mechanism of this regulation, we cloned the human NaP(i)-IIb gene and promoter region and studied the effect of EGF on NaP(i)-IIb gene transcription. The human NaP(i)-IIb gene has 12 exons and 11 introns. Two transcription initiation sites were identified by primer extension. Additionally, 2.8 kb of the 5'-flanking region of the gene was characterized as a functional promoter in human intestinal (Caco-2) and human lung (A549) cells. Additional studies showed that EGF inhibited promoter activity by 40-50% in Caco-2 cells and that actinomycin D treatment abolished this inhibition. EGF had no effect on promoter activity in lung (A549) cells. We conclude that the human NaP(i)-IIb gene promoter is functional in Caco-2 and A549 cells and that the gene is responsive to EGF by a transcriptionally mediated mechanism in intestinal cells.
• Xu, H., Collins, J. F., Bai, L., Kiela, P. R., Lynch, R. M., & Ghishan, F. K. (2001). Epidermal growth factor regulation of rat NHE2 gene expression. American journal of physiology. Cell physiology, 281(2), C504-13.
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  Epidermal growth factor (EGF) is involved in acute regulation of Na(+)/H(+) exchangers (NHEs), but the effect of chronic EGF administration on NHE gene expression is unknown. The present studies showed that EGF treatment increased NHE2-mediated intestinal brush-border membrane vesicle Na(+) absorption and NHE2 mRNA abundance by nearly twofold in 19-day-old rats. However, no changes were observed in renal NHE2 mRNA or intestinal and renal NHE3 mRNA abundance. To understand the mechanism of this regulation, we developed the rat intestinal epithelial (RIE) cell as an in vitro model to study the effect of EGF on NHE2 gene expression. EGF increased functional NHE2 activity and mRNA abundance in cultured RIE cells, and this stimulation could be blocked by actinomycin D (a transcriptional inhibitor). Additionally, NHE2 promoter reporter gene assays in transiently transfected RIE cells showed an almost twofold increase in promoter activity after EGF treatment. We conclude that rat NHE2 activity can be stimulated by chronic EGF treatment and that this response is at least partially mediated by gene transcription.
• Billerey-Larmonier, C., Uno, J. K., Larmonier, N., Midura, A. J., Timmermann, B., Ghishan, F. K., & Kiela, P. R. (2000). Protective effects of dietary curcumin in mouse model of chemically induced colitis are strain dependent. INFLAMMATORY BOWEL DISEASES, 14(6), 780-793.
• Collins, J. F., Kiela, P. R., Xu, H., & Ghishan, F. K. (2000). Expression of rat, renal NHE2 and NHE3 during postnatal development. Biochimica et biophysica acta, 1464(1), 7-17.
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  The current studies were designed to characterize the expression of sodium-hydrogen exchangers NHE2 and NHE3 during rat, renal ontogeny. NHE2 mRNA and immunoreactive protein were more highly expressed at 2 and 3 weeks of age, with declining levels into adulthood. In situ hybridization of NHE2 mRNA localized the message to the renal inner cortex and outer medullary regions and suggested higher mRNA levels in suckling animals as compared to adults. Immunohistochemical analysis of rat kidney with the NHE2 antiserum showed specific staining of the distal convoluted tubules. In contrast, NHE3 mRNA expression was lowest in 2-week animals and higher in older rats, while NHE3 immunoreactive protein showed constant expression levels during development. Additionally uptake experiments utilizing HOE694 showed no change in NHE2 or NHE3 functional protein expression in 2-week-old rats versus adults. We conclude that the developmental increase in NHE2 mRNA and immunoreactive protein expression cannot be detected by functional assays, which suggests that NHE2 does not play a role in sodium absorption by the renal tubules (as has been previously suggested). Additionally, molecular changes seen in NHE3 mRNA expression do not affect functional protein activity, suggesting increased mRNA translational efficiency or protein stability in suckling rats.
• Kiela, P. R., Guner, Y. S., Xu, H., Collins, J. F., & Ghishan, F. K. (2000). Age- and tissue-specific induction of NHE3 by glucocorticoids in the rat small intestine. American journal of physiology. Cell physiology, 278(4), C629-37.
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  Of the two known apical isoforms of the Na(+)/H(+) exchanger (NHE) family, only the NHE3 gene is regulated by glucocorticoids. The aim of these studies was to investigate the mechanisms underlying the effects of methylprednisolone (MP) on expression of NHE3 in the proximal and distal small intestine of suckling and adult rats. Immunoblots showed that the glucocorticoid responsiveness in the proximal small intestine was greatest in suckling animals (NHE3/beta-actin: 0.43 +/- 0.09 control vs. 1.57 +/- 0.15 MP; P < 0. 001), and responsiveness decreased with age with no effect in adults (0.56 +/- 0.14 vs. 0.64 +/- 0.17). Distal small intestine was responsive only in adult rats (0.49 +/- 0.13 vs. 1.65 +/- 0.09; P < 0.001). This pattern was confirmed at the mRNA level and by (22)Na(+) uptake. Western blot and [(3)H]dexamethasone mesylate binding showed that the responsiveness of NHE3 to glucocorticoids is directly related to the expression of glucocorticoid receptor (GR) in the small intestine. These studies suggest that loss and gain of glucocorticoid responsiveness in the proximal and distal small intestine, respectively, are related to age- and segment-dependent expression of GR.
• Kiela, P., Guner, Y., Xu, H., Collins, J., & Ghishan, F. (2000). Age- and tissue-specific induction of NHE3 by glucocorticoids in the rat small intestine. AMERICAN JOURNAL OF PHYSIOLOGY-CELL PHYSIOLOGY, 278(4), C629-C637.
• Bai, L., Collins, J. F., Muller, Y. L., Xu, H., Kiela, P. R., & Ghishan, F. K. (1999). Characterization of cis-elements required for osmotic response of rat Na(+)/H(+) exchanger-2 (NHE-2) gene. The American journal of physiology, 277(4), R1112-9.
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  The Na(+)/H(+) exchanger (NHE-2) has been implicated in osmoregulation in the kidney, because it transports Na(+) across the cell membrane and efficiently alters intracellular osmolarity. On hyperosmotic stress, NHE-2 mRNA increases in abundance in mouse inner medullary collecting duct (mIMCD-3) cells, suggesting possible transcriptional regulation. To investigate the molecular mechanism of potential transcriptional regulation of NHE-2 by hyperosmolarity, we have functionally characterized the 5'-flanking region of the gene in mIMCD-3 cells. Transient transfection of luciferase reporter gene constructs revealed a novel cis-acting element, which we call OsmoE (osmotic-responsive element, bp -808 to -791, GGGCCAGTTGGCGCTGGG), and a TonE-like element (tonicity-responsive element, bp -1201 to -1189, GCTGGAAAACCGA), which together are shown to be responsible for hyperosmotic induction of the NHE-2 gene. Electrophoretic mobility shift assays suggest that different DNA-protein interactions occur between these two osmotic response elements. However, both DNA sequences were shown to specifically bind nuclear proteins that dramatically increase in abundance under hyperosmotic conditions. Isolation of trans-acting factors and characterization of their specific interaction with these osmotic response elements will further elucidate the transcriptional mechanisms controlling NHE-2 gene expression under hyperosmolar conditions.
• Borbon, I. A., Hillman, Z., Duran, E., Kiela, P. R., Frautschy, S. A., & Erickson, R. P. (1999). Lack of efficacy of curcumin on neurodegeneration in the mouse model of Niemann-Pick C1. PHARMACOLOGY BIOCHEMISTRY AND BEHAVIOR, 101(1), 125-131.
• Guner, Y. S., Kiela, P. R., Xu, H., Collins, J. F., & Ghishan, F. K. (1999). Differential regulation of renal sodium-phosphate transporter by glucocorticoids during rat ontogeny. The American journal of physiology, 277(5), C884-90.
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  The effects of chronic administration of methylprednisolone (MP) were studied on the ontogeny of the renal type II Na-P(i) transporter (NaPi-2). Immunoblot analysis showed that MP did not alter the expression of NaPi-2 protein levels in suckling and weanling rats; however, there was an approximately 50% decrease in adolescent and adult rats. There was no change in Na-dependent P(i) uptake in brush-border membrane vesicles in suckling rats, but there was an almost twofold decrease in adolescent rats induced by MP treatment. MP administration did not alter mRNA levels in suckling or adolescent rats. Dual injections with the glucocorticoid receptor blocker RU-486 (mifepristone) and MP did not reverse the downregulation of NaPi-2 immunoreactive protein levels in adolescent rats. To control for RU-486 antagonism efficiency, Na/H exchanger isoform 3 (NHE3) protein levels were also assayed after injection with RU-486 and MP. As expected, NHE3 protein levels increased after MP injection; however, the increase was blocked in adolescent rats by RU-486. We conclude that there is an age-dependent responsiveness to glucocorticoids and that the marked decrease in NaPi-2 immunoreactive protein levels and activity in adolescent rats is due to posttranscriptional mechanisms.
• Guner, Y., Kiela, P., Xu, H., Collins, J., & Ghishan, F. (1999). Differential regulation of renal sodium-phosphate transporter by glucocorticoids during rat ontogeny. AMERICAN JOURNAL OF PHYSIOLOGY-CELL PHYSIOLOGY, 277(5), C884-C890.
• Larmonier, C. B., Uno, J. K., Lee, K., Karrasch, T., Laubitz, D., Thurston, R., Midura-Kiela, M. T., Ghishan, F. K., Sartor, R. B., Jobin, C., & Kiela, P. R. (1999). Limited effects of dietary curcumin on Th-1 driven colitis in IL-10 deficient mice suggest an IL-10-dependent mechanism of protection. AMERICAN JOURNAL OF PHYSIOLOGY-GASTROINTESTINAL AND LIVER PHYSIOLOGY, 295(5), G1079-G1091.
• Zabielski, R., Podgurniak, P., Pierzynowski, S. G., Kiela, P. R., & Colin, G. P. (1999). Cholecystokinin-like activity in the duodenal lumen of anaesthetized neonatal calves. Polish Journal of Veterinary Sciences, 02(1).
• Collins, J. F., Kiela, P. R., Xu, H., Zeng, J., & Ghishan, F. K. (1998). Increased NHE2 expression in rat intestinal epithelium during ontogeny is transcriptionally mediated. The American journal of physiology, 275(4), C1143-50.
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  We have previously described changes in intestinal brush-border membrane vesicle (BBMV) Na+/H+ exchange activity and characterized Na+/H+ exchanger (NHE3) expression during rat ontogeny. The current studies were designed to investigate developmental changes in NHE2 expression in rat intestine. In previous studies, pH-dependent uptake of Na+ in jejunal BBMV utilizing HOE-694 inhibition demonstrated that NHE2 functional protein levels were lowest in 2-wk-old rats, higher in 3-wk-old and adult rats, and highest in 6-wk-old rats [Collins et al. Am. J. Physiol. 273 (Cell Physiol. 42): C1937-C1946, 1997]. In the current investigation, Northern blot analyses showed that NHE2 mRNA levels in the jejunum were similar in 6-wk-old, adult, and 3-wk-old rats and three- to fivefold lower in 2-wk-old rats. In situ hybridization of 2- and 6-wk-old rat intestine with NHE2-specific probes confirmed Northern blot observations. Polyclonal antibodies were developed against an NHE2-specific peptide from amino acids 652-661. Western blots with NHE2 antiserum showed that the intensity of a specific 90-kDa band was lowest in 2-wk-old animals and four- to sixfold higher in 3- and 6-wk-old and adult animals. Immunohistochemical analysis showed specific staining of NHE2 antiserum to only the apical intestinal membrane. Furthermore, nuclear run-on analyses showed a 1.7-fold higher NHE2 transcription rate in 6-wk-old rats than in 2-wk-old rats. Overall, the current data suggest that increases in NHE2 expression upon weaning are mediated by increased gene transcription.
• Collins, J. F., Xu, H., Kiela, P. R., Zeng, J., & Ghishan, F. K. (1998). Ontogeny of basolateral membrane sodium-hydrogen exchange (NHE) activity and mRNA expression of NHE-1 and NHE-4 in rat kidney and jejunum. Biochimica et biophysica acta, 1369(2), 247-58.
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  Na+/H+ exchange (NHE) activity varies with ontogenic state in rat intestinal basolateral membrane vesicles (BLMV). The current investigation sought to determine if these observations are due to differential expression of BLM NHE isoforms, NHE-1 and NHE-4. In rat kidney, BLMV sodium uptake levels were similar in 2, 3 and 6 week rats (13.28+/-0.68, 14.03+/-0.84, and 11.71+/-0.66 nmol Na+/mg protein/30 s, respectively), and lower in adults (5.53+/-0.24) (n=4; p
• Jiang, L., Wang, J., Solorzano-Vargas, R., Tsai, H., Gutierrez, E., Ontiveros, L., Kiela, P., Wu, S., & Martin, M. (1998). Characterization of the rat intestinal Fc receptor (FcRn) promoter: transcriptional regulation of FcRn gene by the Sp family of transcription factors. AMERICAN JOURNAL OF PHYSIOLOGY-GASTROINTESTINAL AND LIVER PHYSIOLOGY, 286(6), G922-G931.
• Zabielski, R., Leśniewska, V., Borlak, J., Gregory, P. C., Kiela, P., Pierzynowski, S. G., & Barej, W. (1998). Effects of intraduodenal administration of tarazepide on pancreatic secretion and duodenal EMG in neonatal calves. Regulatory peptides, 78(1-3), 113-23.
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  The influence of CCK-A receptor antagonism on pancreatic exocrine secretion and duodenal EMG, and the mechanism(s) involved in CCK-induced pancreatic secretion were studied in conscious calves. Seven 1-week-old calves were fitted with a pancreatic duct catheter, duodenal cannula and duodenal electrodes. Pancreatic exocrine secretion and duodenal EMG were studied following intraduodenal CCK-A receptor antagonist (Tarazepide), intravenous atropine, and intravenous or intraduodenal CCK-8 administrations. Tarazepide decreased duodenal electric activity, reduced interdigestive pancreatic secretion, especially protein; reduced cephalic and early postprandial (milk) induced secretion of bicarbonate and protein. Pancreatic protein secretion to intravenous CCK-8 was little affected by atropine, but was significantly reduced by Tarazepide+/-atropine; in contrast, protein secretion to intraduodenal CCK-8 was abolished by Tarazepide or atropine. We conclude that pre- and especially early postprandial pancreatic secretion are partly controlled via CCK-A (mainly mucosal) mediated mechanisms.
• Collins, J. F., Xu, H., Kiela, P. R., Zeng, J., & Ghishan, F. K. (1997). Functional and molecular characterization of NHE3 expression during ontogeny in rat jejunal epithelium. The American journal of physiology, 273(6), C1937-46.
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  Ontogenic changes occur in intestinal brush-border membrane vesicle (BBMV) Na+/H+ exchange activity. The present studies were designed to investigate ontogenic changes in Na+/H+ exchanger (NHE) isoform 3 in rat jejunum. pH-dependent Na+ uptake was assayed in four age groups of rats in the presence of 0, 50, or 800 microM HOE-694, a specific NHE inhibitor with differential sensitivities for NHE2 [inhibition constant (Ki) = 5 microM in PS120 fibroblasts] and NHE3 (Ki = 650 microM). Results showed that NHE2 and NHE3 contribute to basal BBMV uptake at all ages. Uptake levels were highest in 6-wk-old rats, lower in adult rats, and lowest in 2-wk-old (suckling) and 3-wk-old (weanling) rats, NHE3 contribution ranged from 92% at 6 wk of age to 59% at 2 and 3 wk of age. NHE3 inhibition by 800 microM HOE-694 was 38-45%. Statistical analysis showed that HOE-694 had a significant effect at both concentrations at all ages and that differences were present between all ages except 2- and 3-wk rats (at all HOE-694 concentrations). Northern blot analyses of jejunal mucosa showed lowest NHE3 mRNA levels in 2-wk animals and higher levels in all other age groups. Polyclonal antibodies were developed against an NHE3 COOH-terminal fusion protein, and antiserum was characterized with NHE3-transfected PS120 cells and by immunohistochemistry. Western blot analyses showed lowest protein levels in 2-wk animals and higher levels in the other ages. Suckling rats were subcutaneously injected with methylprednisone (MP) for 2 days and killed 1 day later. Northern blot analyses showed a twofold increase in NHE3 mRNA expression with MP treatment. Immunoblot analyses showed a 2.5-fold increase in NHE3 immunoreactive protein levels with MP injection. Overall, these data suggest that NHE3 is regulated during ontogeny and that ontogenic changes are most apparent around the time of weaning. Furthermore, the data suggest that NHE3 is regulated at transcriptional and posttranscriptional levels during mammalian intestinal development.
• Collins, J., Xu, H., Kiela, P., Zeng, J., & Ghishan, F. (1997). Ontogeny of basolateral membrane sodium-hydrogen exchange (NHE) activity and mRNA expression of NHE-1 and NHE-4 in rat kidney and jejunum. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES, 1369(2), 247-258.
• Rantzer, D., Kiela, P., Thaela, M. J., Svendsen, J., Ahrén, B., Karlsson, S., & Pierzynowski, S. G. (1997). Pancreatic exocrine secretion during the first days after weaning in pigs. Journal of animal science, 75(5), 1324-31.
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  Feed replacement at weaning plays an important role in the induction of pancreatic maturation. To understand the changes in the exocrine pancreas at weaning and the relation to postweaning problems, we studied the function of the exocrine pancreas and changes of intestinal hemolytic Escherichia coli in four pigs. The pigs were chronically fitted with pancreatic duct catheters and T-shaped cannula inserted into the duodenum for reintroduction of pancreatic juice. One day before weaning (at 30 d of age), pancreatic juice was collected for 1 h before and 1 h after a morning and an evening suckling. The pigs were not creep fed, but from weaning the pigs received a standard weaning diet ad libitum. On d 1, 2, 3, and 5 after weaning, pancreatic juice was collected continuously for the 24-h period. The total pancreatic secretion was measured at hourly intervals, 1.5-mL samples were taken for analysis, and the remaining juice was returned to the animal. On these days, samples from the duodenum, ileum, and rectum were also taken for analyses of hemolytic E. coli. From the day before to 5 d after weaning, a gradual increase in pancreatic secretion was observed concerning volume (P < .001) and protein (P < .01) and trypsin (P < .02) levels. An increase (P < .01) in hemolytic E. coli in the duodenal contents was also documented during this period. We assume that the gradual increase in the measured variables of pancreatic secretion is related to the increasing consumption of solid feed. However, the appearance of E. coli and disappearance of milk components from the gastrointestinal tract could be other factors stimulating the exocrine pancreas.
• Zabielski, R., Kiela, P., Lesniewska, ., Krzeminski, R., Mikolajczyk, M., & Barej, W. (1997). Kinetics of pancreatic juice secretion in relation to duodenal migrating myoelectric complex in preruminant and ruminant calves fed twice daily. BRITISH JOURNAL OF NUTRITION, 78(3), 427-442.
• Zabielski, R., Kiela, P., Leśniewska, V., Krzemiński, R., Mikołajczyk, M., & Barej, W. (1997). Kinetics of pancreatic juice secretion in relation to duodenal migrating myoelectric complex in preruminant and ruminant calves fed twice daily. The British journal of nutrition, 78(3), 427-42.
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  Daily secretion of pancreatic juice, including postprandial responses to food, was investigated in two groups of calves: preruminant (fed with liquid food) and ruminant (fed with solid food). Male Friesian calves (1 week old and 6 weeks old) were surgically fitted with a pancreatic duct catheter, duodenal cannula and two duodenal electrodes. Continuous 24 h collections of pancreatic juice and myoelectrical recordings were performed with minimal restraint and disturbance of animals. In both groups of calves clear periodic fluctuations in pancreatic juice secretion (volume, protein output and trypsin activity) coinciding with duodenal migrating myoelectric complexes (MMC) were recorded. Secretion of juice per cycle and per day was greater in ruminant calves, but the frequency and amplitude of cycles were lower in this group. There were no differences between day and night-time preprandial pancreatic cycles and duodenal MMC in preruminant calves, whilst in ruminant calves, evening MMC were longer than morning MMC. The pancreatic cephalic phase (increase of volume flow, protein output and trypsin activity during and just after food intake) was significant only in preruminant calves following morning feeding. Postprandial pancreatic cycles did not differ from preprandial cycles, except the pancreatic cycle (juice volume and trypsin activity) in which food was offered in preruminant calves. No gastric or intestinal phase was observed in either group of calves. In conclusion, biological cycles of the gastrointestinal tract are present in both preruminant and ruminant calves, and these cycles evolve along with the change from liquid to solid food.
• Kiela, P., Zabielski, R., Podgurniak, P., Midura, M., Barej, W., Gregory, P., & Pierzynowski, S. G. (1996). Cholecystokinin-8 and vasoactive intestinal polypeptide stimulate exocrine pancreatic secretion via duodenally mediated mechanisms in the conscious pig. Experimental physiology, 81(3), 375-84.
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  The effects of local and peripheral administration of cholecystokinin-8 (CCK-8) and vasoactive intestinal polypeptide (VIP) on basal pancreatic secretion were investigated in conscious pigs. Five pigs (20 +/- 2 kg, mean +/- S.E.M.) were chronically fitted with a T-shaped cannula in the duodenum, and catheters in the pancreatic duct, jugular vein, and right gastroepiploic artery. The arterial catheter was inserted against the bloodstream with its tip opposite the duodenal branch(es) of the right gastroepiploic artery, so that all injected peptides would reach the duodenal arterial circulation excluding the pancreas. Pancreatic secretion during basal conditions (i.e. after an overnight fast) exhibited a characteristic cyclic pattern (cycle duration, 70 +/- 4.2 min). Secretion volume oscillated between 0.2 +/- 0.04 and 4.0 +/- 0.9 ml kg-1 h-1 (P < 0.001), trypsin output between 9.6 +/- 1.9 and 29.1 +/- 4.1 U kg-1 h-1 (P < 0.001) and protein output between 0.36 +/- 0.08 and 9.2 +/- 1.7 mg kg-1 h-1 (P < 0.001). Infusion into the jugular vein for 1 min, during the trough of pancreatic secretion, of either CCK-8 (15 pmol kg-1 min-1) or VIP (7 pmol kg-1 min-1) did not stimulate pancreatic secretion. However, local infusion of an identical dose of CCK-8 or VIP into the duodenal arterial circulation increased the volume, protein output and trypsin output of the pancreatic juice (P < 0.05 to < 0.001). These results indicate that CCK-8 and VIP can stimulate the exocrine pancreas by a duodenally mediated mechanism.
• Kruszewska, D., Kiela, P., Ljungh, A., Erlwanger, K., Westrom, B., Linderoth, A., & Pierzynowski, S. (1996). Enteral crude red kidney bean (Phaseolus vulgaris) lectin phytohernagglutinin induces maturational changes in the enterocyte membrane proteins of suckling rats. BIOLOGY OF THE NEONATE, 84(2), 152-158.
• Collins, J., Kiela, P., Xu, H., Zeng, J., & Ghishan, F. (1995). Increased NHE2 expression in rat intestinal epithelium during ontogeny is transcriptionally mediated. AMERICAN JOURNAL OF PHYSIOLOGY-CELL PHYSIOLOGY, 275(4), C1143-C1150.
• Zabielski, R., Kiela, P., Onaga, T., Mineo, H., Gregory, P. C., & Kato, S. (1995). Effect of neural blockades, gastrointestinal regulatory peptides, and diversion of gastroduodenal contents on periodic pancreatic secretion in the preruminant calf. Canadian journal of physiology and pharmacology, 73(11), 1616-24.
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  The role of nerves, gastrointestinal peptides, and gastroduodenal contents in the regulation of pancreatic periodic function were studied in preruminant calves. Nine male, Friesian calves were surgically fitted with pancreatic and duodenal catheters, abomasal and duodenal cannulae, and duodenal electrodes. Pancreatic secretion oscillated in phase with the duodenal migrating myoelectric complex. Pancreatic secretion and duodenal motility were abolished by intravenous atropine (5 micrograms.kg-1.min-1). The frequency of pancreatic and duodenal cycles was similarly increased by motilin and decreased by pituitary adenylate cyclase activating polypeptide-27; secretin lengthened duodenal but not pancreatic cycles, resulting in loss of synchronization; cholecystokinin-8 and secretin increased pancreatic secretion (all infusions at 120 pmol.kg-1.h-1); intraduodenal lidocaine (2%) or diversion of gastroduodenal contents reduced pancreatic secretion without altering periodicity. In conclusion, generation of pancreatic as well as of duodenal periodicity in the calf depends upon cholinergic neural efferent input. Secretin, cholecystokinin-8, pituitary adenylate cyclase activating polypeptide, duodenal contents, and mucosal afferent receptors seem to have relatively minor regulatory roles but can modulate the level of pancreatic secretion. The importance of enteric neural influence from the duodenum and the role of motilin in the regulation of pancreatic periodicity and its synchronization with the duodenal motility cycle remain to be determined.
• Bai, L., Collins, J., Muller, Y., Xu, H., Kiela, P., & Ghishan, F. (1994). Characterization of cis-elements required for osmotic response of rat Na+/H+ exchanger-2 (NHE-2) gene. AMERICAN JOURNAL OF PHYSIOLOGY-REGULATORY INTEGRATIVE AND COMPARATIVE PHYSIOLOGY, 277(4), R1112-R1119.
• Funk, J. L., Frye, J. B., Oyarzo, J. N., Kuscuoglu, N., Wilson, J., McCaffrey, G., Stafford, G., Chen, G., Lantz, R. C., Jolad, S. D., Solyom, A. M., Kiela, P. R., & Timmermann, B. N. (1994). Efficacy and mechanism of action of turmeric supplements in the treatment of experimental arthritis. ARTHRITIS AND RHEUMATISM, 54(11), 3452-3464.
• Uno, J. K., Kolek, O. I., Hines, E. R., Xu, H., Timmermann, B. N., Kiela, P. R., & Ghishan, F. K. (1992). The role of tumor necrosis factor alpha in down-regulation of osteoblast Phex gene expression in experimental murine colitis. GASTROENTEROLOGY, 131(2), 497-509.

Proceedings Publications

• Kiela, P. R. (2022, May). Gut microbiota modulates PARP1-driven PARylation to control colonic inflammation. In Digestive Disease Week Meeting/Annual Meeting of the American Gastroenterological Association, Gastroenterology, Vol. 162, S-106.
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  Background:Poly-ADP-ribosylation (PARylation) isa dynamic posttranslational modification driven by poly(ADP-ribose) polymerases. PARylation involves enzymatic transfer of ADPribose from NAD+ to specific target proteins and plays key roles in cellular biology. Our previous work showed that genetic ablation of Parp1 confers protection from dextran sulfate sodium (DSS)-induced colitis with concurrent changes in gut microbial composition, and expansion of colonic regulatoryT cells (PMID: 26912654). Aim:Thisworkaimstoinvestigate role of gut microbiota in modulating PARP1 expression and PARylation in colonic mucosa underhomeostasis andduring IBD-associateddysbiosis, and the role of epithelial hyperPARylation in the pathogenesis of experimental colitis. Methods: Colonic expression of PARP1 and PARylated targets was evaluated by immunofluorescence in biopsies from healthy and IBD patients, in the colon of DSS-treated mice, in wild-type germ-free (WT GF) mice, GF mice colonized with fecal bacteria from Specific Pathogen Free (SPF) mice (WT Ex-GF), conventionally reared SPF mice (WT SPF), in SPF Parp1-/- mice, and in GF mice associated with gut semi-defined microbiota from healthy or Crohn's disease (ileocolitis, CD_L3) patients. Colonic metabolome was assessed in WT and Parp1-/- mice by untargeted metabolomics (Metabolon). Recovery from DSS-induced injury was studied in mice with epithelialspecific (Vil-Cre) Parp1 deletion (Parp1DIEC) and Cre- littermates. Results: Both CD and UC, as well as murine DSS colitis were associated with dramatically increased mucosal PARylation. Conventional WT SPF, but not Parp1-/- mice showed easily detectable PARP1 expression and mucosal PARylation (undetectable in Parp1-/-) which was reduced by broadspectrum antibiotics. In GF mice, PARP1 protein expression was very low with no detectable PARylation. Colonization of GF mice with SPF microbiota significantly increased colonic PARP1/PARylation. GF mice transferred with microbiota from CD_L3 patients had dramatically increased PARylation compared to healthy controls. Fecal metabolites from CD_L3 patients induced hyperPARylation in Caco2 cells or in human colonoids. Finally, PARP1DIEC mice showed significantly improved recovery from DSS-induced mucosal injury as compared to PARPWT,as measuredby body weightrecovery, histology score, colon length, and mucosal cytokine expression. Conclusions: Colonic PARylation is primarily driven by PARP1, a process under the control of and modulated by commensal microbiota. Dysbiotic microbial community from CD_L3 patients induces mucosal hyperPARylation, a process detrimental to the host since epithelial-specific Parp1 knockout significantly improved recovery from mucosal injury. Approaches to prevent hyperPARylation in the colonic mucosa may therefore represent viable strategy to improve IBD outcomes.
• Thaela, M., Cornelissen, G., Halberg, F., Rantzer, D., Kiela, P., Svendsen, J., Pierzynowski, G., Laplace, J., Fevrier, C., & Barbeau, A. (2013, 1997). Rhythmicity of pancreatic secretion in pigs fed ad libitum five days after weaning. In DIGESTIVE PHYSIOLOGY IN PIGS, 608-612.
• Rantzer, D., Svendsen, J., Samuelsson, O., Kiela, P., Thaela, M., Pierzynowski, S., Laplace, J., Fevrier, C., & Barbeau, A. (2006, 1997). Developmental aspects of pancreatic exocrine secretion at weaning in the pig.. In DIGESTIVE PHYSIOLOGY IN PIGS, 190-193.

Presentations

• Dutta Dey, P., Sheikh, I. A., Saha, T., Midura-Kiela, M. T., Harris, D., Ghishan, F. K., & Kiela, P. R. (2023, May). Epithelial Aldh1a1 modulates colonic microenvironment to imprint tolerogenic DC phenotype and promote FoxP3⁺RORgT⁺ regulatory T cells.. Digestive Disease Week Meeting/Annual Meeting of the American Gastroenterological Association. Chicago, IL: American Gastroenterological Association.
• Madan, J. C., & Kiela, P. R. (2023, May). The Emerging Role of the Gut Microbiome in the Gut-Brain Axis and Neuroinflammation in PANS/PANDAS. Inflammatory Brain Disorders Conference 2023. Online: Neuroimmune Foundation.
• Kiela, P. R. (2022, October). The gut brain axis and neuroinflammation: the microbiome in PANS. PANDAS/PANS: Recognizing, Understanding, and Treating Immune-Mediated Neuropsychiatric Disorders. The 2nd Alex Manfull Fund Symposium. Portsmouth, NH: Alex Manfull Fund.
• Kiela, P. R. (2019, October). Preliminary insight into the microbiome of twins discordant for PANDAS (Pediatric Autoimmune Neuropsychiatric Disorder Associated with Streptococcal Infection). PANDAS/PANS: Advances in Diagnosis and Treatment for Post-Infectious Auto-Immune Basal Ganglia Encephalitis. Portsmouth, NH: Alex Manfull Memorial Fund – PANDAS Network.
• Kiela, P. R., West, J. J., Murray, M., Galindo, K., Mayate-Ortiz, L., Laubitz, D., Daines, M. O., & Rice, S. A. (2019, May). Assessing the Causes, Epidemiology and Under-diagnosis of Pediatric Acute-onset Neuropsychiatric Syndrome (PANS) in Arizonans. 4th Annual ABRC Research Conference, Phoenix, AZ May 2, 2019. Phoenix, AZ: Arizona Biomedical Research Commission.
• Jamwal, D. R., Laubitz, D., Harrison, C. A., Cox, C. M., Midura-Kiela, M., Gurney, M. A., Lybarger, L. P., Wilson, J. M., Ghishan, F. K., & Kiela, P. R. (2018, MAY). INTESTINAL EPITHELIAL MHCII EXPRESSION MODULATES THE COURSE OF AUTOIMMUNE AND INFECTIOUS COLITIS IN A MOUSE MODEL OF CONDITIONAL I-A(B) KNOCKOUT. Digestive Disease Week Meeting. Washington D.C.: American Gastroenterological Association.
• Laubitz, D., Gurney, M. A., Midura-Kiela, M., Ghishan, F. K., & Kiela, P. R. (2018, MAY). DECREASED EXPRESSION OF NHE3 IN COLON CANCER EPITHELIUM IS ASSOCIATED WITH DNA DAMAGE, INCREASED LOCAL INFLAMMATION AND TUMOR GROWTH. Digestive Disease Week Meeting. Washington D.C.: American Gastroenterological Association.
• Gurney, M. A., Laubitz, D., Xu, H., Ghishan, F. K., & Kiela, P. R. (2016, April). Intrinsic Effects of Reduced NHE3 Activity in Intestinal Epithelial Cells. Digestive Disease Week. San Diego, USA: American Gastroenterological Association.
• Radhakrishnan, V. M., Dehdashti, N., Gilpatrick, M. M., Kiela, P. R., & Ghishan, F. K. (2016, April). Post Transcriptional Regulation of Colonic Cav1.3 By IFNγ in Colitis: Potential Implications for IBD-Associated Impaired Intestinal Ca2+ Absorption and Bone Loss. Digestive Disease Week. San Diego, USA: American Gastroenterological Association.

Poster Presentations

• Saha, T., Gurney, M. A., Bernardazzi, C., Midura-Kiela, M. T., Ghishan, F. K., & Kiela, P. R. (2023, May). Inhibition of NHE3 mediates increased proliferation and migration of colonic epithelial cells. Digestive Disease Week Meeting/Annual Meeting of the American Gastroenterological Association. Chicago, IL: American Gastroenterological Association.
• Kiela, P. R. (2022, January). Decreased Expression of NHE3 in Colon Cancer Epithelium is Associated with DNA Damage, Increased Local Inflammation and Tumor Growth.. Crohn’s and Colitis Congress 2022. Virtual: Crohn’s and Colitis Foundation.
• Rice, S. A., Daines, M. O., Kiela, P. R., & Mayate, L. (2021, February). Assessing the Causes, Epidemiology and Under-diagnosis of Pediatric Acute-onset Neuropsychiatric Syndrome (PANS) in Arizonans. Arizona Biomedical Research Commission, Annual Research Conference. Phoenix, Arizona: ABRC.
• Gurney, M. A., Laubitz, D., Harrison, C. A., Ghishan, F. K., & Kiela, P. R. (2018, MAY). LONG-TERM REDUCTION OF NHE3 EXPRESSION IN COLON CANCER CELLS ACTIVATES AMPK, AND LEADS TO ENERGY CRISIS WHILE PROMOTING CELL SURVIVAL AND PROLIFERATION. Digestive Disease Week. Washington D.C.: American Gastroenterological Association.
• Harrison, C. A., Laubitz, D., Jamwal, D. R., Midura-Kiela, M., Ghishan, F. K., & Kiela, P. R. (2018, MAY). DIFFERENTIAL RESPONSE TO BROAD-SPECTRUM ANTIBIOTICS BY THE GUT MICROBIOTA IN MALE AND FEMALE MICE DURING COLITIS. Digestive Disease Week Meeting. Washington D.C.: American Gastroenterological Association.
• Laubitz, D., Kiela, P. R., Chau, B. T., Lantz, R. C., Burgess, J. L., O'Rourke, M., & Kurzius-Spencer, M. R. (2018, APR). Dietary Arsenic and Gut Microbiome Analysis. Experimental Biology. San Diego, CA.
• Laubitz, D., Midura-Kiela, M., Ghishan, F. K., & Kiela, P. R. (2018, MAY). DYNAMICS OF GUT MICROBIOME RECOVERY AFTER BROAD-SPECTRUM ANTIBIOTIC TREATMENT IN YOUNG AND OLD MICE. Digestive Disease Week. Washington D.C.: American Gastroenterological Association.

Reviews

• Ghishan, F. K., & Kiela, P. R. (2013. Advances in the understanding of mineral and bone metabolism in inflammatory bowel diseases(pp G191-G201).
• Ghishan, F. K., & Kiela, P. R. (1998. Small intestinal ion transport(pp 130-134).

Others

• Laubitz, D., Bai, A., Larmonier, C. B., Midura-Kiela, M. T., Thurston, R. D., Kiela, P. R., & Ghishan, F. K. (2014, APR). Spontaneous distal colitis in NHE3-deficient mice. GASTROENTEROLOGY.
• Radhakrishnan, V. M., Thurston, R. D., Larmonier, C. B., Fritz, A., Ramalingam, R., Kiela, P. R., & Ghishan, F. K. (2012, APR). Transcriptional regulation of renal NCX1 by IFN gamma in colitis. FASEB JOURNAL.
• Majewski, P., Thurston, R. D., Kiela, P. R., & Ghishan, F. K. (2011, MAY). NF-kappa B Signaling Mediates TNF alpha-Induced Inhibition of Phex Expression. GASTROENTEROLOGY.
• Kiela, P., Midura, A., Kuscuoglu, N., Midura-Kiela, M., & Ghishan, F. (2010, JAN). Molecular mechanism of rat NHE3 promoter regulation by sodium butyrate.. JOURNAL OF INVESTIGATIVE MEDICINE.
• Hines, E., Kolek, O., Jones, M., Serey, S., Sirjani, N., Kiela, P., Jurutka, P., Haussler, M., Collins, J., & Ghishan, F. (2009, OCT). 1,25-dihydroxyvitamin D downregulates PHEX gene expression in osteolblasts via repression of a 110 kDa positive transfactor that binds to a polyadenine element in the promoter. JOURNAL OF BONE AND MINERAL RESEARCH.
• Laubitz, D., Larmonier, C. B., Midura-Kiela, M. T., Thurston, R. D., Kiela, P. R., & Ghishan, F. K. (2009, MAY). Changes in Mucosal Homeostasis Leading to Hypersensitivity to Mucosal Injury in NHE3 Knockout Mice. GASTROENTEROLOGY.
• Uno, J. K., Mah, A. T., Tooley, J. E., Xu, H., Kiela, P. R., & Ghishan, F. K. (2009, APR). Altered expression of renal sodium-phosphate cotransporter in mice with chemically induced colitis. FASEB JOURNAL.
• Kiela, P. R., Larmonier, C. B., Kiela, M. M., Thurston, R. D., & Ghishan, F. (2008, APR). Hypersensitivity to DSS-induced mucosal injury in NHE3 knockout mice. GASTROENTEROLOGY.
• Kiela, P. R., Majewski, P. M., Thurston, R. D., Ramalingam, R., Sabetisoofyani, A., & Ghishan, F. K. (2008, APR). Cooperative role of NF-kappa B signaling and PARP-1 activity in the TNF-induced inhibition of PHEX gene expression. FASEB JOURNAL.
• Kiela, P., Midura, A., Kuscuoglu, N., Midura-Kiela, M., Collins, J., & Ghishan, F. (2008, APR). Molecular mechanism of rat NHE3 promoter regulation by sodium butyrate. GASTROENTEROLOGY.
• Hines, E., Kiela, P., & Collins, J. (2007, APR). Molecular cloning and glucocorticoid responsiveness of the murine PHEX gene promoter.. GASTROENTEROLOGY.
• Midura-Kiela, M. T., Larmonier, C. B., Laubitz, D., Ghishan, F. K., & Kiela, P. R. (2007, APR). Curcumin inhibits IFN-gamma signaling in colonic epithelial cells. GASTROENTEROLOGY.
• Ramalingam, R., Larmonier, C. B., Bommireddy, R., Ghishan, F. K., & Kiela, P. R. (2007, APR). Lack of TGF-beta signaling in dendritic cells leads to systemic autoimmunity. FASEB JOURNAL.
• Ghishan, F. K., & Kiela, P. R. (2006, JUN). From probiotics to therapeutics: another step forward?. JOURNAL OF CLINICAL INVESTIGATION.
• Larmonier, C. B., Laubitz, D., Bucknam, A. L., Thurston, R. D., Hill, F. M., Midura-Kiela, M. T., Ramalingam, R., Kiela, P. R., & Ghishan, F. K. (2006, MAY). Role of NHE3 in the Maintenance of Intestinal Barrier Integrity in IL-10-Deficient Mice. GASTROENTEROLOGY.
• Midura-Kiela, M. T., Larmonier, C. B., Laubitz, D., Ghishan, F. K., & Kiela, P. R. (2006, APR). Curcumin Inhibits IFN-gamma Signaling in Colonic Epithelial Cells. FASEB JOURNAL.
• Typpo, K., Larmonier, C., Deschenes, J., Kiela, P., Theodorou, A., & Ghishan, F. (2006, DEC). INTESTINAL INJURY IN CHILDREN AFTER CARDIOPULMONARY BYPASS. CRITICAL CARE MEDICINE.
• Kolek, O., Hines, E., Jones, M., LeSueur, L., Kiela, P., Haussler, M., & Ghishan, F. (2005, JAN). 1 alpha,25-dihydroxyvitamin D3 up-regulates fibroblast growth factor 23 gene expression in a rat osteoblastic cell line and mouse calvaria.. JOURNAL OF INVESTIGATIVE MEDICINE.
• Kiela, P. R., Thurston, R. D., Larmonier, C. B., Ramalingam, R., & Ghishan, F. K. (2004, MAY). Evaluation of Bone Mineral Density in Four Distinct Models of Colitis. GASTROENTEROLOGY.
• Bai, L., Collins, J., Muller, Y., Xu, H., Kiela, P., & Ghishan, F. (2003, APR). Identification of osmotic response elements from the rat sodium-hydrogen exchanger isoform 2 (NHE-2) gene. GASTROENTEROLOGY.
• Kiela, P., Collins, J., Guner, J., Xu, H., Bai, L., & Ghishan, F. (2002, APR). Age and tissue-specific induction of NHE3 by glucocorticoids in rat small intestine.. GASTROENTEROLOGY.
• Larmonier, C. B., Woodford, R. T., Hill, F. M., Schreiner, R., Ramalingam, R., Besselsen, D. G., Ghishan, F. K., & Kiela, P. R. (2002, MAY). High Vitamin D Diet Leads to a Paradoxical Decrease of Bone Mineral Density in Adoptive T-Cell Transfer Colitis. GASTROENTEROLOGY.
• Billerey-Larmonier, C., Midura-Kiela, M. T., Midura, A. J., Ghishan, F. K., & Kiela, P. R. (2001, APR). Curcumin modulates neutrophil migration at multiple levels. GASTROENTEROLOGY.
• Hua, P., Xu, H., Uno, J. K., Kiela, P. R., & Ghishan, F. K. (2000, APR). Basal promoter activation of rat NHE2 gene in intestinal epithelial cells. GASTROENTEROLOGY.
• Kolek, O., Hines, E., Jones, M., LeSueur, L., Lipko, M., Kiela, P., Haussler, M., Collins, J., & Ghishan, F. (1999, APR). 1a,25-dihydroxyvitamin D3 up-regulates Fgf23 gene expression in a rat ostcoblastic cell line and mouse calvaria. GASTROENTEROLOGY.
• Larmonier, C. B., Uno, J. K., Lipko, M. A., Larmonier, N., Ghishan, F., & Kiela, P. R. (1998, APR). Protective effects of dietary curcumin in trinitrobenzene sulfonic acid (TNBS)-induced colitis are mouse strain-dependent. GASTROENTEROLOGY.
• Uno, J. K., Feferman, H. R., Kolek, O. I., Xu, H., Kiela, P. R., & Ghishan, F. K. (1998, APR). Poly a element is involved in TNF alpha mediated decreases in Phex gene transcription. GASTROENTEROLOGY.
• Kiela, P. R., Thurston, R. D., Larmonier, C. B., Ramalingam, R., Laubitz, D., Sabetisoofyani, A., & Ghishan, F. K. (1997, MAY). Renal CA(2+) Wasting in Murine Models of Crohn's Disease is Mediated by Concerted Downregulation of Klotho and TRPV5 in Distal Convoluted Tubules. GASTROENTEROLOGY.
• Kiela, P., Lesueur, J., Collins, J., & Ghishan, F. (1997, APR). Rat NHE-3 promoter is TATA-less and regulated by Sp1 and GATA transcription factors. GASTROENTEROLOGY.
• Ramalingam, R., Midura-Kiela, M. T., Woodford, R. T., Ghishan, F. K., & Kiela, P. R. (1997, MAY). Increased Activation of Dendritic Cells Contributes to T-Cell Mediated Colitis but Not Gastritis in DC-TGFBR2 Ko Mice. GASTROENTEROLOGY.