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Magnuson FS, Christensen P, Krassioukov A, Rodriguez G, Emmanuel A, Kirshblum S, Krogh K. Neurogenic Bowel Dysfunction in Patients with Spinal Cord Injury and Multiple Sclerosis-An Updated and Simplified Treatment Algorithm. J Clin Med 2023; 12:6971. [PMID: 38002586 PMCID: PMC10672578 DOI: 10.3390/jcm12226971] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2023] [Revised: 10/27/2023] [Accepted: 11/02/2023] [Indexed: 11/26/2023] Open
Abstract
Neurogenic bowel dysfunction (NBD) is a common condition in individuals with spinal cord injury (SCI) or multiple sclerosis (MS). It usually entails constipation, difficult evacuation of the rectum, and fecal incontinence (FI); often in combination. It is highly burdensome for affected patients and is correlated with poor quality of life. The current treatment algorithm, or treatment pyramid, does not completely correspond to actual clinical practice, and the known and classical pyramid contains both treatments still in their experimental stage as well as several treatments which are not available at all treatment centers. Thus, an updated treatment algorithm is called upon, and the authors of this paper therefore propose a simplified version of the treatment pyramid, aiming to guide clinicians in treating NBD.
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Affiliation(s)
- Fredrika S. Magnuson
- Department of Hepatology and Gastroenterology, Aarhus University Hospital, 8200 Aarhus, Denmark
| | - Peter Christensen
- Department of Surgery, Aarhus University Hospital, 8200 Aarhus, Denmark
| | - Andrei Krassioukov
- International Collaboration of Repair Discoveries (ICORD), Department of Medicine, Division of Physical Medicine and Rehabilitation, The University of British Columbia, Vancouver, BC V5Z 1M9, Canada
| | - Gianna Rodriguez
- Physical Medicine and Rehabilitation, Spinal Cord Injury Medicine, University of Michigan Health, Ann Arbor, MI 48108, USA
| | - Anton Emmanuel
- GI Physiology Unit, University College London Hospital, London WC1E 6DB, UK
| | - Steven Kirshblum
- Kessler Institute for Rehabilitation, West Orange, NJ 07052, USA;
- Department of Physical Medicine and Rehabilitation, Rutgers New Jersey Medical School, Newark, NJ 07103, USA
| | - Klaus Krogh
- Department of Hepatology and Gastroenterology, Aarhus University Hospital, 8200 Aarhus, Denmark
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2
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Dengler F, Domenig O, Kather S, Burgener IA, Steiner JM, Heilmann RM. Dysregulation of intestinal epithelial electrolyte transport in canine chronic inflammatory enteropathy and the role of the renin-angiotensin-aldosterone-system. Front Vet Sci 2023; 10:1217839. [PMID: 37720474 PMCID: PMC10500592 DOI: 10.3389/fvets.2023.1217839] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2023] [Accepted: 08/18/2023] [Indexed: 09/19/2023] Open
Abstract
Chronic diarrhea is a hallmark sign of canine chronic inflammatory enteropathy (CIE), leading to fluid and electrolyte losses. Electrolyte homeostasis is regulated by the renin-angiotensin-aldosterone-system (RAAS), which might be involved in (counter-)regulating electrolyte losses in canine CIE. Whether and which electrolyte transporters are affected or if RAAS is activated in canine CIE is unknown. Thus, intestinal electrolyte transporters and components of the RAAS were investigated in dogs with CIE. Serum RAAS fingerprint analysis by mass spectrometry was performed in 5 CIE dogs and 5 healthy controls, and mRNA levels of intestinal electrolyte transporters and local RAAS pathway components were quantified by RT-qPCR in tissue biopsies from the ileum (7 CIE, 10 controls) and colon (6 CIE, 12 controls). Concentrations of RAAS components and mRNA expression of electrolyte transporters were compared between both groups of dogs and were tested for associations among each other. In dogs with CIE, associations with clinical variables were also tested. Components of traditional and alternative RAAS pathways were higher in dogs with CIE than in healthy controls, with statistical significance for Ang I, Ang II, and Ang 1-7 (all p < 0.05). Expression of ileal, but not colonic electrolyte transporters, such as Na+/K+-ATPase, Na+/H+-exchanger 3, Cl- channel 2, down-regulated in adenoma, and Na+-glucose-cotransporter (all p < 0.05) was increased in CIE. Our results suggest that the dys- or counter-regulation of intestinal electrolyte transporters in canine CIE might be associated with a local influence of RAAS. Activating colonic absorptive reserve capacities may be a promising therapeutic target in canine CIE.
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Affiliation(s)
- Franziska Dengler
- Institute of Physiology, Pathophysiology and Biophysics, University of Veterinary Medicine Vienna, Vienna, Austria
| | | | - Stefanie Kather
- Department for Small Animals, College of Veterinary Medicine, University of Leipzig, Leipzig, SN, Germany
| | - Iwan A. Burgener
- Small Animal Internal Medicine, University of Veterinary Medicine Vienna, Vienna, Austria
| | - Joerg M. Steiner
- Gastrointestinal Laboratory, School of Veterinary Medicine and Biomedical Sciences, Texas A&M University, College Station, TX, United States
| | - Romy M. Heilmann
- Department for Small Animals, College of Veterinary Medicine, University of Leipzig, Leipzig, SN, Germany
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3
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Sarker R, Lin R, Singh V, Donowitz M, Tse CM. SLC26A3 (DRA) is stimulated in a synergistic, intracellular Ca 2+-dependent manner by cAMP and ATP in intestinal epithelial cells. Am J Physiol Cell Physiol 2023; 324:C1263-C1273. [PMID: 37154494 PMCID: PMC10243534 DOI: 10.1152/ajpcell.00523.2022] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2022] [Revised: 04/24/2023] [Accepted: 04/24/2023] [Indexed: 05/10/2023]
Abstract
In polarized intestinal epithelial cells, downregulated in adenoma (DRA) is an apical Cl-/[Formula: see text] exchanger that is part of neutral NaCl absorption under baseline conditions, but in cyclic adenosine monophosphate (cAMP)-driven diarrheas, it is stimulated and contributes to increased anion secretion. To further understand the regulation of DRA in conditions mimicking some diarrheal diseases, Caco-2/BBE cells were exposed to forskolin (FSK) and adenosine 5'-triphosphate (ATP). FSK and ATP stimulated DRA in a concentration-dependent manner, with ATP acting via P2Y1 receptors. FSK at 1 µM and ATP at 0.25 µM had minimal to no effect on DRA given individually; however, together, they stimulated DRA to levels seen with maximum concentrations of FSK and ATP alone. In Caco-2/BBE cells expressing the Ca2+ indicator GCaMP6s, ATP increased intracellular Ca2+ (Ca2+i) in a concentration-dependent manner, whereas FSK (1 µM), which by itself did not significantly alter Ca2+i, followed by 0.25 µM ATP produced a large increase in Ca2+ that was approximately equal to the elevation caused by 1 µM ATP. 1,2-Bis(2-aminophenoxy)ethane-N,N,N',N'-tetraacetic acid tetrakis(acetoxymethyl ester) (BAPTA-AM) pretreatment prevented the ATP and FSK/ATP synergistically increased the DRA activity and the increase in Ca2+i caused by FSK/ATP. FSK/ATP synergistic stimulation of DRA was similarly observed in human colonoids. In Caco-2/BBE cells, subthreshold concentrations of FSK (cAMP) and ATP (Ca2+) synergistically increased Ca2+i and stimulated DRA activity with both being blocked by BAPTA-AM pretreatment. Diarrheal diseases, such as bile acid diarrhea, in which both cAMP and Ca2+ are elevated, are likely to be associated with stimulated DRA activity contributing to increased anion secretion, whereas separation of DRA from Na+/H+ exchanger isoform-3 (NHE3) contributes to reduced NaCl absorption.NEW & NOTEWORTHY The BB Cl-/[Formula: see text] exchanger DRA takes part in both neutral NaCl absorption and stimulated anion secretion. Using intestinal cell line, Caco-2/BBE high concentrations of cAMP and Ca2+ individually stimulated DRA activity, whereas low concentrations, which had no/minimal effect, synergistically stimulated DRA activity that required a synergistic increase in intracellular Ca2+. This study increases understanding of diarrheal diseases, such as bile salt diarrhea, in which both cAMP and elevated Ca2+ are involved.
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Affiliation(s)
- Rafiquel Sarker
- Division of Gastroenterology and Hepatology, Department of Medicine, The Johns Hopkins University School of Medicine, Baltimore, Maryland, United States
| | - Ruxian Lin
- Division of Gastroenterology and Hepatology, Department of Medicine, The Johns Hopkins University School of Medicine, Baltimore, Maryland, United States
| | - Varsha Singh
- Division of Gastroenterology and Hepatology, Department of Medicine, The Johns Hopkins University School of Medicine, Baltimore, Maryland, United States
| | - Mark Donowitz
- Division of Gastroenterology and Hepatology, Department of Medicine, The Johns Hopkins University School of Medicine, Baltimore, Maryland, United States
- Department of Physiology, The Johns Hopkins University School of Medicine, Baltimore, Maryland, United States
| | - Chung-Ming Tse
- Division of Gastroenterology and Hepatology, Department of Medicine, The Johns Hopkins University School of Medicine, Baltimore, Maryland, United States
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Rida R, Hodeify R, Kreydiyyeh S. Adverse effect of FTY720P on colonic Na + /K + ATPase is mediated via ERK, p38MAPK, PKC, and PI3K. J Appl Toxicol 2023; 43:220-229. [PMID: 35946054 DOI: 10.1002/jat.4375] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2022] [Revised: 08/05/2022] [Accepted: 08/06/2022] [Indexed: 01/17/2023]
Abstract
FTY720P, an analogue of sphingosine 1-phosphate, has emerged lately as a potential causative agent of inflammatory bowel disease, in which electrolytes movements driven by the sodium gradient established by the Na+ /K+ ATPase are altered. We showed previously in Caco-2 cells, a 50% FTY720P-induced decrease in the ATPase activity, mediated via S1PR2 and PGE2. This work aims at delineating the mechanism underlying PGE2 release and at investigating if the ATPase inhibition is due to changes in its abundance. The activity of the ATPase and the localization of a GFP-tagged Na+ /K+ -ATPase α1 -subunit were assessed in cells treated with 7.5 nM FTY720P. The involvement of ERK, p38 MAPK, PKC, and PI3K was studied in cells treated with 7.5 nM FTY720P or 1 nM PGE2 in presence of their inhibitors, or by determining changes in the protein expression of their activated phosphorylated forms. Imaging data showed ∼30% reduction in the GFP-tagged Na+ /K+ ATPase at the plasma membrane. Both FTY720P and PGE2 showed, respectively, 50% and 60% reduction in ATPase activity that disappeared when p38 MAPK, PKC, and PI3K were inhibited individually but not with ERK inhibition. The effect of FTY720P was imitated by PMA, an activator of PKC. Western blotting revealed inhibition of ERK by FTY720P. It was concluded that FTY720P, through activation of S1PR2, downregulates the Na+ /K+ ATPase by inhibiting ERK, which in turn activates p38 MAPK leading to the sequential activation of PKC and PI3K, PGE2 release, and a decrease in the Na+ /K+ ATPase activity and membrane abundance.
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Affiliation(s)
- Reem Rida
- Department of Biology, Faculty of Arts and Sciences, American University of Beirut, Beirut, Lebanon
| | - Rawad Hodeify
- Department of Biotechnology, School of Arts and Sciences, American University of Ras Al Khaimah, Ras Al Khaimah, United Arab Emirates
| | - Sawsan Kreydiyyeh
- Department of Biology, Faculty of Arts and Sciences, American University of Beirut, Beirut, Lebanon
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Peritore-Galve FC, Kaji I, Smith A, Walker LM, Shupe JA, Washington MK, Algood HMS, Dudeja PK, Goldenring JR, Lacy DB. Increased intestinal permeability and downregulation of absorptive ion transporters Nhe3, Dra, and Sglt1 contribute to diarrhea during Clostridioides difficile infection. Gut Microbes 2023; 15:2225841. [PMID: 37350393 PMCID: PMC10291935 DOI: 10.1080/19490976.2023.2225841] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/09/2022] [Accepted: 06/09/2023] [Indexed: 06/24/2023] Open
Abstract
BACKGROUND & AIM Clostridioides difficile infection (CDI) is the leading cause of hospital-acquired diarrhea and pseudomembranous colitis. Two protein toxins, TcdA and TcdB, produced by C. difficile are the major determinants of disease. However, the pathophysiological causes of diarrhea during CDI are not well understood. Here, we investigated the effects of C. difficile toxins on paracellular permeability and apical ion transporters in the context of an acute physiological infection. METHODS We studied intestinal permeability and apical membrane transporters in female C57BL/6J mice. Üssing chambers were used to measure paracellular permeability and ion transporter function across the intestinal tract. Infected intestinal tissues were analyzed by immunofluorescence microscopy and RNA-sequencing to uncover mechanisms of transporter dysregulation. RESULTS Intestinal permeability was increased through the size-selective leak pathway in vivo during acute CDI in a 2-day-post infection model. Chloride secretory activity was reduced in the cecum and distal colon during infection by decreased CaCC and CFTR function, respectively. SGLT1 activity was significantly reduced in the cecum and colon, accompanied by ablated SGLT1 expression in colonocytes and increased luminal glucose concentrations. SGLT1 and DRA expression was ablated by either TcdA or TcdB during acute infection, but NHE3 was decreased in a TcdB-dependent manner. The localization of key proteins that link filamentous actin to the ion transporters in the apical plasma membrane was unchanged. However, Sglt1, Nhe3, and Dra were drastically reduced at the transcript level, implicating downregulation of ion transporters in the mechanism of diarrhea during CDI. CONCLUSIONS CDI increases intestinal permeability and decreases apical abundance of NHE3, SGLT1, and DRA. This combination likely leads to dysfunctional water and solute absorption in the large bowel, causing osmotic diarrhea. These findings provide insights into the pathophysiological mechanisms underlying diarrhea and may open novel avenues for attenuating CDI-associated diarrhea.
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Affiliation(s)
- F. Christopher Peritore-Galve
- Department of Pathology, Microbiology, and Immunology, Vanderbilt University Medical Center, Nashville, TN, USA
- Vanderbilt Institute for Infection, Immunology, and Inflammation, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Izumi Kaji
- Section of Surgical Sciences, Vanderbilt University Medical Center, Nashville, TN, USA
- Epithelial Biology Center, Vanderbilt University School of Medicine, Nashville, TN, USA
| | - Anna Smith
- Department of Pathology, Microbiology, and Immunology, Vanderbilt University Medical Center, Nashville, TN, USA
- Vanderbilt Institute for Infection, Immunology, and Inflammation, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Lauren M. Walker
- Department of Pathology, Microbiology, and Immunology, Vanderbilt University Medical Center, Nashville, TN, USA
- Vanderbilt Institute for Infection, Immunology, and Inflammation, Vanderbilt University Medical Center, Nashville, TN, USA
- Vanderbilt Vaccine Center, Vanderbilt University Medical Center, Nashville, TN, USA
| | - John A. Shupe
- Department of Pathology, Microbiology, and Immunology, Vanderbilt University Medical Center, Nashville, TN, USA
- Vanderbilt Institute for Infection, Immunology, and Inflammation, Vanderbilt University Medical Center, Nashville, TN, USA
| | - M. Kay Washington
- Department of Pathology, Microbiology, and Immunology, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Holly M. Scott Algood
- Department of Pathology, Microbiology, and Immunology, Vanderbilt University Medical Center, Nashville, TN, USA
- Vanderbilt Institute for Infection, Immunology, and Inflammation, Vanderbilt University Medical Center, Nashville, TN, USA
- Department of Veterans Affairs, Tennessee Valley Healthcare System, Nashville, TN, USA
| | - Pradeep K. Dudeja
- Division of Gastroenterology and Hepatology, Department of Medicine, University of Illinois at Chicago, Chicago, IL, USA
- Department of Veterans Affairs, Jesse Brown Veterans Affairs Medical Center, Chicago, IL, USA
| | - James R. Goldenring
- Vanderbilt Institute for Infection, Immunology, and Inflammation, Vanderbilt University Medical Center, Nashville, TN, USA
- Section of Surgical Sciences, Vanderbilt University Medical Center, Nashville, TN, USA
- Epithelial Biology Center, Vanderbilt University School of Medicine, Nashville, TN, USA
- Department of Veterans Affairs, Tennessee Valley Healthcare System, Nashville, TN, USA
- Cell and Developmental Biology, Vanderbilt University School of Medicine, Nashville, TN, USA
| | - D. Borden Lacy
- Department of Pathology, Microbiology, and Immunology, Vanderbilt University Medical Center, Nashville, TN, USA
- Vanderbilt Institute for Infection, Immunology, and Inflammation, Vanderbilt University Medical Center, Nashville, TN, USA
- Department of Veterans Affairs, Tennessee Valley Healthcare System, Nashville, TN, USA
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Anbazhagan AN, Priyamvada S, Kumar A, Jayawardena D, Borthakur A, Gill RK, Alrefai WA, Dudeja PK, Saksena S. Downregulation of NHE-3 (SLC9A3) expression by MicroRNAs in intestinal epithelial cells. Am J Physiol Cell Physiol 2022; 323:C1720-C1727. [PMID: 36189974 PMCID: PMC9722255 DOI: 10.1152/ajpcell.00294.2022] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2022] [Revised: 09/26/2022] [Accepted: 09/29/2022] [Indexed: 11/22/2022]
Abstract
Na+/H+ exchanger-3 (NHE-3) is the major apical membrane transporter involved in vectorial Na+ absorption in the intestine. Dysregulation of NHE-3 expression and/or function has been implicated in pathophysiology of diarrhea associated with gut inflammation and infections. Therefore, it is critical to understand the mechanisms involved in the regulation of NHE-3 expression. MicroRNAs (miRNAs) are highly conserved small RNAs that can regulate gene expression at the posttranscriptional level. To date, however, very little is known about the regulation of NHE-3 expression by microRNAs. Therefore, current studies were undertaken to examine the potential miRNA candidates that can regulate the expression of NHE-3 in intestinal epithelial cells. In silico analysis, using different algorithms, predicted several miRNAs that target NHE-3. MicroRNAs with highest context and target score, miR-326, miR-744-5p, and miR-330-5p, were selected for the current study. Human NHE-3 gene 3' untranslated region [3'UTR; 160 base pair (bp)] was cloned into pmirGLO vector upstream of luciferase reporter and transiently transfected with mimics of miR-326, miR-744-5p, and miR-330-5p into Caco-2, HT-29, and SK-CO15 cells. Cotransfection of NHE-3 3' UTR with miR-326 and -miR-330-5p mimics resulted in a significant decrease in relative luciferase activity. Transfection of miR-326 and -330-5p mimics into SK-CO15 cells significantly decreased the NHE-3 protein expression, with no change in NHE-3 messenger ribonucleic acid (mRNA) levels. Our findings demonstrate a novel mechanism for posttranscriptional regulation of NHE-3 by miR-326 and -330-5p by translational repression. We speculate that miR-326 and -330-5p dependent pathways may be involved in modulating NHE-3 expression under physiological and pathophysiological conditions.
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Affiliation(s)
- Arivarasu N Anbazhagan
- Division of Gastroenterology & Hepatology, Department of Medicine, University of Illinois at Chicago, Chicago, Illinois
| | - Shubha Priyamvada
- Division of Gastroenterology & Hepatology, Department of Medicine, University of Illinois at Chicago, Chicago, Illinois
| | - Anoop Kumar
- Division of Gastroenterology & Hepatology, Department of Medicine, University of Illinois at Chicago, Chicago, Illinois
- Jesse Brown VA Medical Center, Chicago, Illinois
| | - Dulari Jayawardena
- Division of Gastroenterology & Hepatology, Department of Medicine, University of Illinois at Chicago, Chicago, Illinois
| | - Alip Borthakur
- Joan C. Edwards School of Medicine, Marshall University, Huntington, West Virginia
| | - Ravinder K Gill
- Division of Gastroenterology & Hepatology, Department of Medicine, University of Illinois at Chicago, Chicago, Illinois
| | - Waddah A Alrefai
- Division of Gastroenterology & Hepatology, Department of Medicine, University of Illinois at Chicago, Chicago, Illinois
- Jesse Brown VA Medical Center, Chicago, Illinois
| | - Pradeep K Dudeja
- Division of Gastroenterology & Hepatology, Department of Medicine, University of Illinois at Chicago, Chicago, Illinois
- Jesse Brown VA Medical Center, Chicago, Illinois
| | - Seema Saksena
- Division of Gastroenterology & Hepatology, Department of Medicine, University of Illinois at Chicago, Chicago, Illinois
- Jesse Brown VA Medical Center, Chicago, Illinois
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Nikolovska K, Seidler UE, Stock C. The Role of Plasma Membrane Sodium/Hydrogen Exchangers in Gastrointestinal Functions: Proliferation and Differentiation, Fluid/Electrolyte Transport and Barrier Integrity. Front Physiol 2022; 13:899286. [PMID: 35665228 PMCID: PMC9159811 DOI: 10.3389/fphys.2022.899286] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2022] [Accepted: 04/19/2022] [Indexed: 12/11/2022] Open
Abstract
The five plasma membrane Na+/H+ exchanger (NHE) isoforms in the gastrointestinal tract are characterized by distinct cellular localization, tissue distribution, inhibitor sensitivities, and physiological regulation. NHE1 (Slc9a1) is ubiquitously expressed along the gastrointestinal tract in the basolateral membrane of enterocytes, but so far, an exclusive role for NHE1 in enterocyte physiology has remained elusive. NHE2 (Slc9a2) and NHE8 (Slc9a8) are apically expressed isoforms with ubiquitous distribution along the colonic crypt axis. They are involved in pHi regulation of intestinal epithelial cells. Combined use of a knockout mouse model, intestinal organoid technology, and specific inhibitors revealed previously unrecognized actions of NHE2 and NHE8 in enterocyte proliferation and differentiation. NHE3 (Slc9a3), expressed in the apical membrane of differentiated intestinal epithelial cells, functions as the predominant nutrient-independent Na+ absorptive mechanism in the gut. The new selective NHE3 inhibitor (Tenapanor) allowed discovery of novel pathophysiological and drug-targetable NHE3 functions in cystic-fibrosis associated intestinal obstructions. NHE4, expressed in the basolateral membrane of parietal cells, is essential for parietal cell integrity and acid secretory function, through its role in cell volume regulation. This review focuses on the expression, regulation and activity of the five plasma membrane Na+/H+ exchangers in the gastrointestinal tract, emphasizing their role in maintaining intestinal homeostasis, or their impact on disease pathogenesis. We point to major open questions in identifying NHE interacting partners in central cellular pathways and processes and the necessity of determining their physiological role in a system where their endogenous expression/activity is maintained, such as organoids derived from different parts of the gastrointestinal tract.
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Yang X, Yao S, An J, Jin H, Wang H, Tuo B. SLC26A6 and NADC‑1: Future direction of nephrolithiasis and calculus‑related hypertension research (Review). Mol Med Rep 2021; 24:745. [PMID: 34458928 DOI: 10.3892/mmr.2021.12385] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2021] [Accepted: 07/30/2021] [Indexed: 11/06/2022] Open
Abstract
Nephrolithiasis is the most common type of urinary system disease in developed countries, with high morbidity and recurrence rates. Nephrolithiasis is a serious health problem, which eventually leads to the loss of renal function and is closely related to hypertension. Modern medicine has adopted minimally invasive surgery for the management of kidney stones, but this does not resolve the root of the problem. Thus, nephrolithiasis remains a major public health issue, the causes of which remain largely unknown. Researchers have attempted to determine the causes and therapeutic targets of kidney stones and calculus‑related hypertension. Solute carrier family 26 member 6 (SLC26A6), a member of the well‑conserved solute carrier family 26, is highly expressed in the kidney and intestines, and it primarily mediates the transport of various anions, including OXa2‑, HCO3‑, Cl‑ and SO42‑, amongst others. Na+‑dependent dicarboxylate‑1 (NADC‑1) is the Na+‑carboxylate co‑transporter of the SLC13 gene family, which primarily mediates the co‑transport of Na+ and tricarboxylic acid cycle intermediates, such as citrate and succinate, amongst others. Studies have shown that Ca2+ oxalate kidney stones are the most prevalent type of kidney stones. Hyperoxaluria and hypocitraturia notably increase the risk of forming Ca2+ oxalate kidney stones, and the increase in succinate in the juxtaglomerular device can stimulate renin secretion and lead to hypertension. Whilst it is known that it is important to maintain the dynamic equilibrium of oxalate and citrate in the kidney, the synergistic molecular mechanisms underlying the transport of oxalate and citrate across kidney epithelial cells have undergone limited investigations. The present review examines the results from early reports studying oxalate transport and citrate transport in the kidney, describing the synergistic molecular mechanisms of SLC26A6 and NADC‑1 in the process of nephrolithiasis formation. A growing body of research has shown that nephrolithiasis is intricately associated with hypertension. Additionally, the recent investigations into the mediation of succinate via regulation of the synergistic molecular mechanism between the SLC26A6 and NADC‑1 transporters is summarized, revealing their functional role and their close association with the inositol triphosphate receptor‑binding protein to regulate blood pressure.
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Affiliation(s)
- Xingyue Yang
- Department of Gastroenterology, Affiliated Hospital of Zunyi Medical University, Zunyi, Guizhou 563003, P.R. China
| | - Shun Yao
- Department of Gastroenterology, Affiliated Hospital of Zunyi Medical University, Zunyi, Guizhou 563003, P.R. China
| | - Jiaxing An
- Department of Gastroenterology, Affiliated Hospital of Zunyi Medical University, Zunyi, Guizhou 563003, P.R. China
| | - Hai Jin
- Department of Gastroenterology, Affiliated Hospital of Zunyi Medical University, Zunyi, Guizhou 563003, P.R. China
| | - Hui Wang
- Department of Gastroenterology, Affiliated Hospital of Zunyi Medical University, Zunyi, Guizhou 563003, P.R. China
| | - Biguang Tuo
- Department of Gastroenterology, Affiliated Hospital of Zunyi Medical University, Zunyi, Guizhou 563003, P.R. China
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9
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Yu Q. Slc26a3 (DRA) in the Gut: Expression, Function, Regulation, Role in Infectious Diarrhea and Inflammatory Bowel Disease. Inflamm Bowel Dis 2021; 27:575-584. [PMID: 32989468 DOI: 10.1093/ibd/izaa256] [Citation(s) in RCA: 23] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/28/2020] [Indexed: 12/12/2022]
Abstract
BACKGROUND The transport of transepithelial Cl- and HCO3- is crucial for the function of the intestinal epithelium and maintains the acid-based homeostasis. Slc26a3 (DRA), as a key chloride-bicarbonate exchanger protein in the intestinal epithelial luminal membrane, participates in the electroneutral NaCl absorption of intestine, together with Na+/H+ exchangers. Increasing recent evidence supports the essential role of decreased DRA function or expression in infectious diarrhea and inflammatory bowel disease (IBD). METHOD In this review, we give an overview of the current knowledge of Slc26a3, including its cloning and expression, function, roles in infectious diarrhea and IBD, and mechanisms of actions. A better understanding of the physiological and pathophysiological relevance of Slc26a3 in infectious diarrhea and IBD may reveal novel targets for future therapy. CONCLUSION Understanding the physiological function, regulatory interactions, and the potential mechanisms of Slc26a3 in the pathophysiology of infectious diarrhea and IBD will define novel therapeutic approaches in future.
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Affiliation(s)
- Qin Yu
- Department of Gastroenterology, Tongji Hospital, Huazhong University of Science and Technology, Wuhan City, China
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10
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Di Meglio L, Grimaldi G, Esposito F, Gelzo M, Esposito MV, Castaldo G, Canani RB. Step-Up Approach for Sodium Butyrate Treatment in Children With Congenital Chloride Diarrhea. Front Pediatr 2021; 9:810765. [PMID: 35127600 PMCID: PMC8811473 DOI: 10.3389/fped.2021.810765] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/07/2021] [Accepted: 12/28/2021] [Indexed: 11/13/2022] Open
Abstract
OBJECTIVES Oral salt substitutive therapy is pivotal for the survival of patients with congenital chloride diarrhea (CLD), however this therapy is unable to influence the symptoms severity. Butyrate has been proposed to limit diarrhea severity in CLD. Unfortunately, the optimal dose schedule is still largely undefined. In addition, butyrate seems not to be well-tolerated by all patients, with some subjects reporting diarrhea worsening. We investigated the efficacy of a step-up therapeutic approach with sodium butyrate in patients who experienced a diarrhea worsening or an absent improvement after the direct administration of 100 mg/kg/day of sodium butyrate. METHODS The efficacy of a step-up therapeutic approach starting from 50 mg/Kg/day with a subsequent 25 mg/kg/day weekly increase up to 100 mg/kg/day of oral sodium butyrate was investigated in previously three unresponsive CLD children. RESULTS The step-up therapeutic approach resulted effective in limiting diarrhea severity in all our three previously unresponsive CLD patients. CONCLUSIONS Our results suggest the efficacy of the step-up therapeutic approach in CLD children.
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Affiliation(s)
- Lavinia Di Meglio
- Department of Translational Medical Science, University Federico II, Naples, Italy.,Diagnostica Ecografica e Prenatale Aniello Di Meglio, Naples, Italy
| | - Giusi Grimaldi
- Department of Translational Medical Science, University Federico II, Naples, Italy
| | - Francesco Esposito
- Department of Translational Medical Science, University Federico II, Naples, Italy
| | - Monica Gelzo
- Genetic Engineering and Advanced Biotechnology Center (CEINGE) Advanced Biotechnologies Research Center, University Federico II, Naples, Italy
| | - Maria Valeria Esposito
- Genetic Engineering and Advanced Biotechnology Center (CEINGE) Advanced Biotechnologies Research Center, University Federico II, Naples, Italy
| | - Giuseppe Castaldo
- Genetic Engineering and Advanced Biotechnology Center (CEINGE) Advanced Biotechnologies Research Center, University Federico II, Naples, Italy
| | - Roberto Berni Canani
- Department of Translational Medical Science, University Federico II, Naples, Italy.,Genetic Engineering and Advanced Biotechnology Center (CEINGE) Advanced Biotechnologies Research Center, University Federico II, Naples, Italy.,Task Force for Microbiome Studies, University Federico II, Naples, Italy
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11
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What Is the Impact of Diet on Nutritional Diarrhea Associated with Gut Microbiota in Weaning Piglets: A System Review. BIOMED RESEARCH INTERNATIONAL 2019; 2019:6916189. [PMID: 31976326 PMCID: PMC6949732 DOI: 10.1155/2019/6916189] [Citation(s) in RCA: 56] [Impact Index Per Article: 11.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/11/2019] [Revised: 11/19/2019] [Accepted: 12/03/2019] [Indexed: 12/11/2022]
Abstract
Piglets experience severe growth challenges and diarrhea after weaning due to nutritional, social, psychological, environmental, and physiological changes. Among these changes, the nutritional factor plays a key role in postweaning health. Dietary protein, fibre, starch, and electrolyte levels are highly associated with postweaning nutrition diarrhea (PWND). In this review, we mainly discuss the high protein, fibre, resistant starch, and electrolyte imbalance in diets that induce PWND, with a focus on potential mechanisms in weaned piglets.
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12
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Swain SD, Grifka-Walk HN, Gripentrog J, Lehmann M, Deuling B, Jenkins B, Liss H, Blaseg N, Bimczok D, Kominsky DJ. Slug and Snail have differential effects in directing colonic epithelial wound healing and partially mediate the restitutive effects of butyrate. Am J Physiol Gastrointest Liver Physiol 2019; 317:G531-G544. [PMID: 31393789 PMCID: PMC6842986 DOI: 10.1152/ajpgi.00071.2019] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Restitution of wounds in colonic epithelium is essential in the maintenance of health. Microbial products, such as the short-chain fatty acid butyrate, can have positive effects on wound healing. We used an in vitro model of T84 colonic epithelial cells to determine if the Snail genes Slug (SNAI2) and Snail (SNAI1), implemented in keratinocyte monolayer healing, are involved in butyrate-enhanced colonic epithelial wound healing. Using shRNA-mediated Slug/Snail knockdown, we found that knockdown of Slug (Slug-KD), but not Snail (Snail-KD), impairs wound healing in scratch assays with and without butyrate. Slug and Snail had differential effects on T84 monolayer barrier integrity, measured by transepithelial resistance, as Snail-KD impaired the barrier (with or without butyrate), whereas Slug-KD enhanced the barrier, again with or without butyrate. Targeted transcriptional analysis demonstrated differential expression of several tight junction genes, as well as focal adhesion genes. This included altered regulation of Annexin A2 and ITGB1 in Slug-KD, which was reflected in confocal microscopy, showing increased accumulation of B1-integrin protein in Slug-KD cells, which was previously shown to impair wound healing. Transcriptional analysis also indicated altered expression of genes associated with epithelial terminal differentiation, such that Slug-KD cells skewed toward overexpression of secretory cell pathway-associated genes. This included trefoil factors TFF1 and TFF3, which were expressed at lower than control levels in Snail-KD cells. Since TFFs can enhance the barrier in epithelial cells, this points to a potential mechanism of differential modulation by Snail genes. Although Snail genes are crucial in epithelial wound restitution, butyrate responses are mediated by other pathways as well.NEW & NOTEWORTHY Although butyrate can promote colonic mucosal healing, not all of its downstream pathways are understood. We show that the Snail genes Snail and Slug are mediators of butyrate responses. Furthermore, these genes, and Slug in particular, are necessary for efficient restitution of wounds and barriers in T84 epithelial cells even in the absence of butyrate. These effects are achieved in part through effects on regulation of β1 integrin and cellular differentiation state.
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Affiliation(s)
- Steve D. Swain
- Department of Microbiology and Immunology, Montana State University, Bozeman, Montana
| | | | - Jeannie Gripentrog
- Department of Microbiology and Immunology, Montana State University, Bozeman, Montana
| | - Margaret Lehmann
- Department of Microbiology and Immunology, Montana State University, Bozeman, Montana
| | - Benjamin Deuling
- Department of Microbiology and Immunology, Montana State University, Bozeman, Montana
| | - Brittany Jenkins
- Department of Microbiology and Immunology, Montana State University, Bozeman, Montana
| | - Hailey Liss
- Department of Microbiology and Immunology, Montana State University, Bozeman, Montana
| | - Nathan Blaseg
- Department of Microbiology and Immunology, Montana State University, Bozeman, Montana
| | - Diane Bimczok
- Department of Microbiology and Immunology, Montana State University, Bozeman, Montana
| | - Douglas J. Kominsky
- Department of Microbiology and Immunology, Montana State University, Bozeman, Montana
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13
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Turck D, Castenmiller J, de Henauw S, Hirsch-Ernst KI, Kearney J, Knutsen HK, Maciuk A, Mangelsdorf I, McArdle HJ, Pelaez C, Pentieva K, Siani A, Thies F, Tsabouri S, Vinceti M, Aggett P, Fairweather-Tait S, Martin A, Przyrembel H, de Sesmaisons-Lecarré A, Naska A. Dietary reference values for chloride. EFSA J 2019; 17:e05779. [PMID: 32626426 PMCID: PMC7009052 DOI: 10.2903/j.efsa.2019.5779] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Following a request from the European Commission, the EFSA Panel on Nutrition, Novel Foods and Food Allergens (NDA) has derived dietary reference values (DRVs) for chloride. There are no appropriate biomarkers of chloride status, no balance studies and no adequate evidence on the relationship between chloride intake and health outcomes that can be used to set DRVs for chloride. There is a close relationship between sodium and chloride balances in the body. Sodium chloride is the main source of both electrolytes in European diets and similar urinary excretion levels of sodium and chloride (on a molar basis) are typically observed in Western populations. Hence, the Panel considered that reference values for chloride can be set at values equimolar to the reference values for sodium for all population groups, and are as follows: 1.7 g/day for children aged 1-3 years, 2.0 g/day for children aged 4-6 years, 2.6 g/day for children aged 7-10 years, 3.1 g/day for children aged 11-17 years and 3.1 g/day for adults including pregnant and lactating women. Consistent with the reference values for sodium, these levels of chloride intake are considered to be safe and adequate for the general EU population, under the consideration that the main dietary source of chloride intake is sodium chloride. For infants aged 7-11 months, an adequate intake of 0.3 g/day is set.
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14
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Palaniappan B, Arthur S, Sundaram VL, Butts M, Sundaram S, Mani K, Singh S, Nepal N, Sundaram U. Inhibition of intestinal villus cell Na/K-ATPase mediates altered glucose and NaCl absorption in obesity-associated diabetes and hypertension. FASEB J 2019; 33:9323-9333. [PMID: 31107610 PMCID: PMC6662973 DOI: 10.1096/fj.201802673r] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2018] [Accepted: 04/23/2019] [Indexed: 01/07/2023]
Abstract
During obesity, diabetes and hypertension inevitably coexist and cause innumerable health disparities. In the obesity, diabetes, and hypertension triad (ODHT), deregulation of glucose and NaCl homeostasis, respectively, causes diabetes and hypertension. In the mammalian intestine, glucose is primarily absorbed by Na-glucose cotransport 1 (SGLT1) and coupled NaCl by the dual operation of Na-H exchange 3 (NHE3) and Cl-HCO3 [down-regulated in adenoma (DRA) or putative anion transporter 1 (PAT1)] exchange in the brush border membrane (BBM) of villus cells. The basolateral membrane (BLM) Na/K-ATPase provides the favorable transcellular Na gradient for BBM SGLT1 and NHE3. How these multiple, distinct transport processes may be affected in ODHT is unclear. Here, we show the novel and broad regulation by Na/K-ATPase of glucose and NaCl absorption in ODHT in multiple species (mice, rats, and humans). In vivo, during obesity inhibition of villus-cell BLM, Na/K-ATPase led to compensatory stimulation of BBM SGLT1 and DRA or PAT1, whereas NHE3 was unaffected. Supporting this new cellular adaptive mechanism, direct silencing of BLM Na/K-ATPase in intestinal epithelial cells resulted in selective stimulation of BBM SGLT1 and DRA or PAT1 but not NHE3. These changes will lead to an increase in glucose absorption, maintenance of traditional coupled NaCl absorption, and a de novo increase in NaCl absorption from the novel coupling of stimulated SGLT1 with DRA or PAT1. Thus, these novel observations provide the pathophysiologic basis for the deregulation of glucose and NaCl homeostasis of diabetes and hypertension, respectively, during obesity. These observations may lead to more efficacious treatment for obesity-associated diabetes and hypertension.-Palaniappan, B., Arthur, S., Sundaram, V. L., Butts, M., Sundaram, S., Mani, K., Singh, S., Nepal, N., Sundaram, U. Inhibition of intestinal villus cell Na/K-ATPase mediates altered glucose and NaCl absorption in obesity-associated diabetes and hypertension.
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Affiliation(s)
- Balasubramanian Palaniappan
- Department of Clinical and Translational Sciences, Joan C. Edwards School of Medicine, Marshall University, Huntington, West Virginia, USA
| | - Subha Arthur
- Department of Clinical and Translational Sciences, Joan C. Edwards School of Medicine, Marshall University, Huntington, West Virginia, USA
| | - Vijaya Lakshmi Sundaram
- Department of Clinical and Translational Sciences, Joan C. Edwards School of Medicine, Marshall University, Huntington, West Virginia, USA
| | - Molly Butts
- Department of Clinical and Translational Sciences, Joan C. Edwards School of Medicine, Marshall University, Huntington, West Virginia, USA
| | - Shanmuga Sundaram
- Department of Clinical and Translational Sciences, Joan C. Edwards School of Medicine, Marshall University, Huntington, West Virginia, USA
| | - Kathiresh Mani
- Department of Clinical and Translational Sciences, Joan C. Edwards School of Medicine, Marshall University, Huntington, West Virginia, USA
| | - Soudamani Singh
- Department of Clinical and Translational Sciences, Joan C. Edwards School of Medicine, Marshall University, Huntington, West Virginia, USA
| | - Niraj Nepal
- Department of Clinical and Translational Sciences, Joan C. Edwards School of Medicine, Marshall University, Huntington, West Virginia, USA
| | - Uma Sundaram
- Department of Clinical and Translational Sciences, Joan C. Edwards School of Medicine, Marshall University, Huntington, West Virginia, USA
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15
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Seidler U, Nikolovska K. Slc26 Family of Anion Transporters in the Gastrointestinal Tract: Expression, Function, Regulation, and Role in Disease. Compr Physiol 2019; 9:839-872. [DOI: 10.1002/cphy.c180027] [Citation(s) in RCA: 34] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
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16
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Abstract
BACKGROUND Persistent diarrhoea (PD), defined as diarrhoeal symptoms for longer than 2 weeks, still forms a substantial disease burden in children under 5 years of age. This article provides an overview of the current knowledge of PD and discusses novel concepts. METHODS A literature search on PD was performed which focused on evidence on epidemiology, pathophysiology and management of the disease. RESULTS The prevalence of PD has potentially decreased over the last decades. Debate remains around the role of specific bacterial, viral and parasitic infections with PD. PD is associated with malnutrition and a compromised immune system, including that caused by HIV infection. Management includes fluid resuscitation and improving nutritional status. There is a lack of evidence on the use of antibiotic therapy for PD. There is increasing interest in nutrient-based interventions, including pre- and/or probiotics that can modify the microbiome and thereby potentially prevent or improve the outcome of PD in children. CONCLUSION As PD remains a significant health burden, multicentre clinical trials are needed to inform future treatment guidelines. ABBREVIATIONS PD, persistent diarrhoea; EED, environmental enteric dysfunction; IBD, inflammatory bowel disease; WHO, World Health Organization.
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Affiliation(s)
- Robert H J Bandsma
- a Division of Gastroenterology, Hepatology and Nutrition , Hospital for Sick Children , Toronto , Canada.,b Translational Medicine Program, Hospital for Sick Children , Toronto , Canada.,c Centre for Global Child Health, Hospital for Sick Children , Toronto , Canada.,d Department of Nutrition Sciences , University of Toronto , Toronto , Canada
| | - Kamran Sadiq
- e Department of Paediatrics and Child Health , Aga Khan University , Karachi , Pakistan
| | - Zulfiqar A Bhutta
- c Centre for Global Child Health, Hospital for Sick Children , Toronto , Canada.,d Department of Nutrition Sciences , University of Toronto , Toronto , Canada.,e Department of Paediatrics and Child Health , Aga Khan University , Karachi , Pakistan
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17
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Yang Z, Ran L, Yuan P, Yang Y, Wang K, Xie L, Huang S, Liu J, Song Z. EGFR as a Negative Regulatory Protein Adjusts the Activity and Mobility of NHE3 in the Cell Membrane of IPEC-J2 Cells With TGEV Infection. Front Microbiol 2018; 9:2734. [PMID: 30483239 PMCID: PMC6243134 DOI: 10.3389/fmicb.2018.02734] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2018] [Accepted: 10/25/2018] [Indexed: 11/13/2022] Open
Abstract
Transmissible gastroenteritis (TGE) has caused devastating economic losses to the swine industry worldwide, despite extensive research focusing on the pathogenesis of virus infection. The molecular pathogenic mechanism of TGEV-induced diarrhea in piglets is unknown. Intestinal diarrhea is closely related to the function of the Na+/H+ exchanger protein NHE3 in the brush border membrane of small intestine epithelial cells. The epidermal growth factor receptor (EGFR) may act to regulate NHE3 expression. In addition, EGFR may promote viral invasion of host cells. The present study aimed to determine whether NHE3 activity is regulated by altering EGFR expression to affect Na+ absorption in TGEV-infected intestinal epithelial cells. Porcine intestinal epithelial cells were used as models for TGEV infection. The results showed that Na+ absorption and NHE3 expression levels decreased in TGEV-infected cells. Proliferation of TGEV within IPEC-J2 cells could be inhibited by treatment with the EGFR inhibitor AG1478 and knockdown; resulting in recovery of Na+ absorption in TGEV infected cells and increasing the activity and expression of NHE3. Moreover, we demonstrated that NHE3 activity was regulated through the EGFR/ERK pathway. Importantly, NHE3 mobility on the plasma membrane of TGEV infected cells was significantly weaker than that in normal cells, and EGFR inhibition and knockdown recovered this mobility. Our research indicated that NHE3 activity was negatively regulated by EGFR in TGEV-infected intestinal epithelial cells.
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Affiliation(s)
- Zhou Yang
- Department of Veterinary Medicine, Southwest University, Chongqing, China
| | - Ling Ran
- Department of Veterinary Medicine, Southwest University, Chongqing, China
| | - Peng Yuan
- Department of Veterinary Medicine, Southwest University, Chongqing, China
| | - Yang Yang
- Department of Veterinary Medicine, Southwest University, Chongqing, China
| | - Kai Wang
- Department of Veterinary Medicine, Southwest University, Chongqing, China
| | - Luyi Xie
- Department of Veterinary Medicine, Southwest University, Chongqing, China
| | - Shilei Huang
- Department of Veterinary Medicine, Southwest University, Chongqing, China
| | - Jia Liu
- Department of Veterinary Medicine, Southwest University, Chongqing, China
| | - Zhenhui Song
- Department of Veterinary Medicine, Southwest University, Chongqing, China
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18
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Coffing H, Priyamvada S, Anbazhagan AN, Salibay C, Engevik M, Versalovic J, Yacyshyn MB, Yacyshyn B, Tyagi S, Saksena S, Gill RK, Alrefai WA, Dudeja PK. Clostridium difficile toxins A and B decrease intestinal SLC26A3 protein expression. Am J Physiol Gastrointest Liver Physiol 2018; 315:G43-G52. [PMID: 29597352 PMCID: PMC6109705 DOI: 10.1152/ajpgi.00307.2017] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/04/2017] [Revised: 03/06/2018] [Accepted: 03/12/2018] [Indexed: 01/31/2023]
Abstract
Clostridium difficile infection (CDI) is the primary cause of nosocomial diarrhea in the United States. Although C. difficile toxins A and B are the primary mediators of CDI, the overall pathophysiology underlying C. difficile-associated diarrhea remains poorly understood. Studies have shown that a decrease in both NHE3 (Na+/H+ exchanger) and DRA (downregulated in adenoma, Cl-/[Formula: see text] exchanger), resulting in decreased electrolyte absorption, is implicated in infectious and inflammatory diarrhea. Furthermore, studies have shown that NHE3 is depleted at the apical surface of intestinal epithelial cells and downregulated in patients with CDI, but the role of DRA in CDI remains unknown. In the current studies, we examined the effects of C. difficile toxins TcdA and TcdB on DRA protein and mRNA levels in intestinal epithelial cells (IECs). Our data demonstrated that DRA protein levels were significantly reduced in response to TcdA and TcdB in IECs in culture. This effect was also specific to DRA, as NHE3 and PAT-1 (putative anion transporter 1) protein levels were unaffected by TcdA and TcdB. Additionally, purified TcdA and TcdA + TcdB, but not TcdB, resulted in a decrease in colonic DRA protein levels in a toxigenic mouse model of CDI. Finally, patients with recurrent CDI also exhibited significantly reduced expression of colonic DRA protein. Together, these findings indicate that C. difficile toxins markedly downregulate intestinal expression of DRA which may contribute to the diarrheal phenotype of CDI. NEW & NOTEWORTHY Our studies demonstrate, for the first time, that C. difficile toxins reduce DRA protein, but not mRNA, levels in intestinal epithelial cells. These findings suggest that a downregulation of DRA may be a critical factor in C. difficile infection-associated diarrhea.
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Affiliation(s)
- Hayley Coffing
- Division of Gastroenterology and Hepatology, Department of Medicine, University of Illinois at Chicago , Chicago, Illinois
| | - Shubha Priyamvada
- Division of Gastroenterology and Hepatology, Department of Medicine, University of Illinois at Chicago , Chicago, Illinois
| | - Arivarasu N Anbazhagan
- Division of Gastroenterology and Hepatology, Department of Medicine, University of Illinois at Chicago , Chicago, Illinois
| | - Christine Salibay
- Department of Pathology, University of Illinois at Chicago , Chicago, Illinois
| | - Melinda Engevik
- Department of Pathology and Immunology, Baylor College of Medicine and Department of Pathology, Texas Children's Hospital , Houston, Texas
| | - James Versalovic
- Department of Pathology and Immunology, Baylor College of Medicine and Department of Pathology, Texas Children's Hospital , Houston, Texas
| | - Mary Beth Yacyshyn
- Division of Digestive Diseases, Department. of Medicine, University of Cincinnati College of Medicine , Cincinnati, Ohio
| | - Bruce Yacyshyn
- Division of Digestive Diseases, Department. of Medicine, University of Cincinnati College of Medicine , Cincinnati, Ohio
| | - Sangeeta Tyagi
- Division of Gastroenterology and Hepatology, Department of Medicine, University of Illinois at Chicago , Chicago, Illinois
| | - Seema Saksena
- Division of Gastroenterology and Hepatology, Department of Medicine, University of Illinois at Chicago , Chicago, Illinois
- Jesse Brown Veterans Affairs Medical Center , Chicago, Illinois
| | - Ravinder K Gill
- Division of Gastroenterology and Hepatology, Department of Medicine, University of Illinois at Chicago , Chicago, Illinois
| | - Waddah A Alrefai
- Division of Gastroenterology and Hepatology, Department of Medicine, University of Illinois at Chicago , Chicago, Illinois
- Jesse Brown Veterans Affairs Medical Center , Chicago, Illinois
| | - Pradeep K Dudeja
- Division of Gastroenterology and Hepatology, Department of Medicine, University of Illinois at Chicago , Chicago, Illinois
- Jesse Brown Veterans Affairs Medical Center , Chicago, Illinois
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19
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Muthusamy S, Jeong JJ, Cheng M, Bonzo JA, Kumar A, Gonzalez FJ, Borthakur A, Dudeja PK, Saksena S, Malakooti J. Hepatocyte nuclear factor 4α regulates the expression of intestinal epithelial Na +/H + exchanger isoform 3. Am J Physiol Gastrointest Liver Physiol 2018; 314:G14-G21. [PMID: 28882825 PMCID: PMC5866373 DOI: 10.1152/ajpgi.00225.2017] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/18/2017] [Revised: 08/28/2017] [Accepted: 08/31/2017] [Indexed: 01/31/2023]
Abstract
Na+/H+ exchanger isoform 3 (NHE3) plays a key role in coupled electroneutral NaCl absorption in the mammalian intestine. Reduced NHE3 expression or function has been implicated in the pathogenesis of diarrhea associated with inflammatory bowel disease (IBD) or enteric infections. Our previous studies revealed transcriptional regulation of NHE3 by various agents such as TNF-α, IFN-γ, and butyrate involving transcription factors Sp1 and Sp3. In silico analysis revealed that the NHE3 core promoter also contains a hepatocyte nuclear factor 4α (HNF-4α) binding site that is evolutionarily conserved in several species suggesting that HNF-4α has a role in NHE3 regulation. Nhe3 mRNA levels were reduced in intestine-specific Hnf4α-null mice. However, detailed mechanisms of NHE3 regulation by HNF-4α are not known. We investigated the regulation of NHE3 gene expression by HNF-4α in vitro in the human intestinal epithelial cell line C2BBe1 and in vivo in intestine-specific Hnf4α-null ( Hnf4αΔIEpC) and control ( Hnf4αfl/fl) mice. HNF-4α knockdown by short interfering RNA in C2BBe1 cells significantly decreased NHE3 mRNA and NHE3 protein levels. Gel mobility shift and chromatin immunoprecipitation assays revealed that HNF-4α directly interacts with the HNF-4α motif in the NHE3 core promoter. Site-specific mutagenesis on the HNF-4α motif decreased, whereas ectopic overexpression of HNF-4α increased, NHE3 promoter activity. Furthermore, loss of HNF-4α in Hnf4αΔIEpC mice decreased colonic Nhe3 mRNA and NHE3 protein levels. Our results demonstrate a novel role for HNF-4α in basal regulation of NHE3 expression. These studies represent an important and novel target for therapeutic intervention in IBD-associated diarrhea. NEW & NOTEWORTHY Our studies for the first time show that hepatocyte nuclear factor 4α directly regulates NHE3 promoter activity and its basal expression in the intestine.
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Affiliation(s)
- Saminathan Muthusamy
- Division of Gastroenterology and Hepatology, Department of Medicine, University of Illinois at Chicago , Chicago, Illinois
| | - Jong Jin Jeong
- Division of Gastroenterology and Hepatology, Department of Medicine, University of Illinois at Chicago , Chicago, Illinois
| | - Ming Cheng
- Division of Gastroenterology and Hepatology, Department of Medicine, University of Illinois at Chicago , Chicago, Illinois
| | - Jessica A Bonzo
- Center for Cancer Research, National Cancer Institute , Bethesda, Maryland
| | - Anoop Kumar
- Division of Gastroenterology and Hepatology, Department of Medicine, University of Illinois at Chicago , Chicago, Illinois
| | - Frank J Gonzalez
- Center for Cancer Research, National Cancer Institute , Bethesda, Maryland
| | - Alip Borthakur
- Division of Gastroenterology and Hepatology, Department of Medicine, University of Illinois at Chicago , Chicago, Illinois
| | - Pradeep K Dudeja
- Division of Gastroenterology and Hepatology, Department of Medicine, University of Illinois at Chicago , Chicago, Illinois
- Jesse Brown Veterans Affairs Medical Center , Chicago, Illinois
| | - Seema Saksena
- Division of Gastroenterology and Hepatology, Department of Medicine, University of Illinois at Chicago , Chicago, Illinois
- Jesse Brown Veterans Affairs Medical Center , Chicago, Illinois
| | - Jaleh Malakooti
- Jesse Brown Veterans Affairs Medical Center , Chicago, Illinois
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20
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Anbazhagan AN, Priyamvada S, Alakkam A, Kumar A, Borthakur A, Saksena S, Gill RK, Alrefai WA, Dudeja PK. Transcriptional modulation of SLC26A3 (DRA) by sphingosine-1-phosphate. Am J Physiol Gastrointest Liver Physiol 2016; 310:G1028-35. [PMID: 27079615 PMCID: PMC4935485 DOI: 10.1152/ajpgi.00308.2015] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/03/2015] [Accepted: 04/12/2016] [Indexed: 01/31/2023]
Abstract
SLC26A3 or Downregulated in adenoma (DRA) is the major Cl(-)/HCO3 (-) exchanger involved in electroneutral NaCl absorption in the mammalian intestine. Alterations in DRA function and expression have been implicated in diarrheal diseases associated with inflammation or infection. Therefore, agents that upregulate DRA activity may serve as potential antidiarrheals. In this regard, sphingosine-1-phosphate (S1P), a member of the bioactive sphingolipid family, has been shown to modulate various cellular processes including improvement of intestinal barrier function. However, the role of S1P in modulating intestinal chloride absorption by regulating DRA is not known. Therefore, the present studies were designed to examine the direct effects of S1P on apical Cl(-)/HCO3 (-) exchange activity and DRA expression. S1P significantly increased Cl(-)/HCO3 (-) exchange activity and also significantly increased DRA mRNA and protein expression. Increased DRA mRNA by S1P was accompanied by enhanced DRA promoter activity, indicating involvement of transcriptional mechanisms. The specific S1P receptor subtype-2 (S1PR2) antagonist JTE-013 blocked the stimulatory effects of S1P on DRA promoter activity, indicating the involvement of S1PR2 S1P-mediated increase in DRA promoter activity involved PI3K/Akt pathway. Progressive deletions of the DRA promoter indicated that the putative S1P-responsive elements are present in the -790/-398 region of the DRA promoter. Furthermore, results obtained from electrophoretic mobility shift assay showed that S1P stimulated DRA promoter activity via increased binding of Ying-Yang1 (YY1) in the S1P-responsive region. In conclusion, transcriptional modulation of DRA expression and function in response to S1P through a PI3/Akt pathway represents a novel role of S1P as a potential proabsorptive agent.
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Affiliation(s)
- Arivarasu N. Anbazhagan
- 2Division of Gastroenterology and Hepatology, Department of Medicine, University of Illinois at Chicago, Chicago, Illinois
| | - Shubha Priyamvada
- 2Division of Gastroenterology and Hepatology, Department of Medicine, University of Illinois at Chicago, Chicago, Illinois
| | - Anas Alakkam
- 2Division of Gastroenterology and Hepatology, Department of Medicine, University of Illinois at Chicago, Chicago, Illinois
| | - Anoop Kumar
- 2Division of Gastroenterology and Hepatology, Department of Medicine, University of Illinois at Chicago, Chicago, Illinois
| | - Alip Borthakur
- 2Division of Gastroenterology and Hepatology, Department of Medicine, University of Illinois at Chicago, Chicago, Illinois
| | - Seema Saksena
- 1Jesse Brown VA Medical Center, Research Service, Chicago, Illinois; and ,2Division of Gastroenterology and Hepatology, Department of Medicine, University of Illinois at Chicago, Chicago, Illinois
| | - Ravinder K. Gill
- 2Division of Gastroenterology and Hepatology, Department of Medicine, University of Illinois at Chicago, Chicago, Illinois
| | - Waddah A. Alrefai
- 1Jesse Brown VA Medical Center, Research Service, Chicago, Illinois; and ,2Division of Gastroenterology and Hepatology, Department of Medicine, University of Illinois at Chicago, Chicago, Illinois
| | - Pradeep K. Dudeja
- 1Jesse Brown VA Medical Center, Research Service, Chicago, Illinois; and ,2Division of Gastroenterology and Hepatology, Department of Medicine, University of Illinois at Chicago, Chicago, Illinois
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21
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Reiner J, Hsieh CJ, Straarup C, Bodammer P, Schäffler H, Graepler F, Stüker D, Kratt T, Linnebacher M, Nadalin S, Witte M, Königsrainer A, Lamprecht G. After Intestinal Transplantation Kidney Function Is Impaired by Downregulation of Epithelial Ion Transporters in the Ileum. Transplant Proc 2016; 48:499-506. [DOI: 10.1016/j.transproceed.2015.12.068] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2015] [Accepted: 12/29/2015] [Indexed: 12/18/2022]
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Di Stadio CS, Altieri F, Miselli G, Elce A, Severino V, Chambery A, Quagliariello V, Villano V, de Dominicis G, Rippa E, Arcari P. AMP18 interacts with the anion exchanger SLC26A3 and enhances its expression in gastric cancer cells. Biochimie 2015; 121:151-60. [PMID: 26700142 DOI: 10.1016/j.biochi.2015.12.010] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2015] [Accepted: 12/01/2015] [Indexed: 01/05/2023]
Abstract
AMP18 is a stomach-specific secreted protein expressed in normal gastric mucosa but absent in gastric cancer. AMP18 plays a major role in maintaining gastric mucosa integrity and is characterized by the presence of a BRICHOS domain consisting of about 100 amino acids, present also in several unrelated proteins, and probably endowed with a chaperon-like activity. In this work, we exploited a functional proteomic strategy to identify potential AMP18 interactors with the aim to add knowledge on its functional role within gastric cell lines and tissues. To this purpose, recombinant biotinylated AMP18 was purified and incubated with protein extract from human normal gastric mucosa by applying an affinity chromatography strategy. The interacting proteins were identified by peptide mass fingerprinting using MALDI-TOF mass spectrometry. The pool of interacting proteins contained SLC26A3, a protein expressed in the apical membrane of intestinal epithelial cells, supposed to play a critical role in Cl(-) absorption and fluid homeostasis. The interaction was also confirmed by Western blot with anti-SLC26A3 on transfected AGS cell extract following AMP18 pull-down. Furthermore, the interaction between AMP18 and SLC26A3 was also validated by confocal microscopy that showed a co-localization of both proteins at plasma membrane level. More importantly, for the first time, we showed that SLC26A3 is down-regulated in gastric cancer and that the overexpression of AMP18 in AMP-transfected gastric cancer cells up-regulated the expression of SLC26A3 both at transcriptional and translational level, the latter probably through the activation of the MAP kinases pathway. These findings strongly suggest that AMP18 might play an anti-inflammatory role in maintaining mucosal integrity also by regulating SLC26A3 level.
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Affiliation(s)
- Chiara Stella Di Stadio
- Department of Molecular Medicine and Medical Biotechnology, University of Naples Federico II, Naples, Italy
| | - Filomena Altieri
- Department of Molecular Medicine and Medical Biotechnology, University of Naples Federico II, Naples, Italy
| | - Giuseppina Miselli
- Department of Molecular Medicine and Medical Biotechnology, University of Naples Federico II, Naples, Italy
| | - Ausilia Elce
- Department of Molecular Medicine and Medical Biotechnology, University of Naples Federico II, Naples, Italy
| | - Valeria Severino
- Department of Environmental, Biological and Pharmaceutical Sciences and Technologies, Second University of Naples, Caserta, Italy
| | - Angela Chambery
- Department of Environmental, Biological and Pharmaceutical Sciences and Technologies, Second University of Naples, Caserta, Italy; IRCCS Multimedica, Milan, Italy
| | - Vincenzo Quagliariello
- Laboratory of Biotechnology, Department of Anesthesia, Surgical and Emergency Sciences, Second University of Naples, Via Costantinopoli 16, I-80138, Naples, Italy
| | - Valentina Villano
- Department of Molecular Medicine and Medical Biotechnology, University of Naples Federico II, Naples, Italy
| | | | - Emilia Rippa
- Department of Molecular Medicine and Medical Biotechnology, University of Naples Federico II, Naples, Italy.
| | - Paolo Arcari
- Department of Molecular Medicine and Medical Biotechnology, University of Naples Federico II, Naples, Italy; CEINGE, Advanced Biotechnology Scarl, Via Gaetano Salvatore 486, I-80145, Naples, Italy.
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23
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Anbazhagan AN, Priyamvada S, Kumar A, Maher DB, Borthakur A, Alrefai WA, Malakooti J, Kwon JH, Dudeja PK. Translational repression of SLC26A3 by miR-494 in intestinal epithelial cells. Am J Physiol Gastrointest Liver Physiol 2014; 306:G123-31. [PMID: 24177028 PMCID: PMC3920076 DOI: 10.1152/ajpgi.00222.2013] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
SLC26A3 [downregulated in adenoma (DRA)] is a Cl(-)/HCO3(-) exchanger involved in electroneutral NaCl absorption in the mammalian intestine. Altered DRA expression levels are associated with infectious and inflammatory diarrheal diseases. Therefore, it is critical to understand the regulation of DRA expression. MicroRNAs (miRNAs) are endogenous, small RNAs that regulate protein expression via blocking the translation and/or promoting mRNA degradation. To investigate potential modulation of DRA expression by miRNA, five different in silico algorithms were used to predict the miRNAs that target DRA. Of these miRNAs, miR-494 was shown to have a highly conserved putative binding site in the DRA 3'-untranslated region (3'-UTR) compared with other DRA-targeting miRNAs in vertebrates. Transfection with pmirGLO dual luciferase vector containing DRA 3'-UTR (pmirGLO-3'-UTR DRA) resulted in a significant decrease in relative luciferase activity compared with empty vector. Cotransfection of the DRA 3'-UTR luciferase vector with a miR-494 mimic further decreased luciferase activity compared with cells transfected with negative control. The transfection of a miR-494 mimic into Caco-2 and T-84 cells significantly increased the expression of miR-494 and concomitantly decreased the DRA protein expression. Mutation of the seed sequences for miR-494 in 3'-UTR of DRA abrogated the effect of miR-494 on 3'-UTR. These data demonstrate a novel regulatory mechanism of DRA expression via miR-494 and indicate that targeting this microRNA may serve to be a potential therapeutic strategy for diarrheal diseases.
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Affiliation(s)
- Arivarasu N. Anbazhagan
- 1Division of Gastroenterology and Hepatology, Department of Medicine, University of Illinois, Chicago, Illinois;
| | - Shubha Priyamvada
- 1Division of Gastroenterology and Hepatology, Department of Medicine, University of Illinois, Chicago, Illinois;
| | - Anoop Kumar
- 1Division of Gastroenterology and Hepatology, Department of Medicine, University of Illinois, Chicago, Illinois;
| | - Daniel B. Maher
- 1Division of Gastroenterology and Hepatology, Department of Medicine, University of Illinois, Chicago, Illinois;
| | - Alip Borthakur
- 1Division of Gastroenterology and Hepatology, Department of Medicine, University of Illinois, Chicago, Illinois;
| | - Waddah A. Alrefai
- 1Division of Gastroenterology and Hepatology, Department of Medicine, University of Illinois, Chicago, Illinois; ,2Jesse Brown Veterans Affairs Medical Center, Chicago, Illinois; and
| | - Jaleh Malakooti
- 1Division of Gastroenterology and Hepatology, Department of Medicine, University of Illinois, Chicago, Illinois;
| | - John H. Kwon
- 3Department of Medicine, University of Chicago, Chicago, Illinois
| | - Pradeep K. Dudeja
- 1Division of Gastroenterology and Hepatology, Department of Medicine, University of Illinois, Chicago, Illinois; ,2Jesse Brown Veterans Affairs Medical Center, Chicago, Illinois; and
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24
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Canani RB, Terrin G, Elce A, Pezzella V, Heinz-Erian P, Pedrolli A, Centenari C, Amato F, Tomaiuolo R, Calignano A, Troncone R, Castaldo G. Genotype-dependency of butyrate efficacy in children with congenital chloride diarrhea. Orphanet J Rare Dis 2013; 8:194. [PMID: 24350656 PMCID: PMC3878237 DOI: 10.1186/1750-1172-8-194] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2013] [Accepted: 12/10/2013] [Indexed: 12/23/2022] Open
Abstract
Background Congenital chloride diarrhea (CLD) is an autosomal recessive disorder characterized by life-long, severe diarrhea with intestinal Cl- malabsorption. It results from a reduced activity of the down regulated in adenoma exchanger (DRA), due to mutations in the solute carrier family 26, member 3 (SLC26A3) gene. Currently available therapies are not able to limit the severity of diarrhea in CLD. Conflicting results have been reported on the therapeutic efficacy of oral butyrate. Methods We investigated the effect of oral butyrate (100 mg/kg/day) in seven CLD children with different SLC26A3 genotypes. Nasal epithelial cells were obtained to assess the effect of butyrate on the expression of the two main Cl- transporters: DRA and putative anion transporter-1 (PAT-1). Results A variable clinical response to butyrate was observed regarding the stool pattern and fecal ion loss. The best response was observed in subjects with missense and deletion mutations. Variable response to butyrate was also observed on SLC26A3 (DRA) and SLC26A6 (PAT1) gene expression in nasal epithelial cells of CLD patients. Conclusions We demonstrate a genotype-dependency for butyrate therapeutic efficacy in CLD. The effect of butyrate is related in part on a different modulation of the expression of the two main apical membrane Cl- exchangers of epithelial cells, members of the SLC26 anion family. Trial registration Australian New Zealand Clinical trial Registry ACTRN12613000450718.
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Affiliation(s)
- Roberto Berni Canani
- Department of Translational Medical Science - Pediatric Section, and European Laboratory for the Investigation of Food Induced Diseases, University of Naples, "Federico II" Via S, Pansini, 5 80131 Naples, Italy.
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25
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Alper SL, Sharma AK. The SLC26 gene family of anion transporters and channels. Mol Aspects Med 2013; 34:494-515. [PMID: 23506885 DOI: 10.1016/j.mam.2012.07.009] [Citation(s) in RCA: 256] [Impact Index Per Article: 23.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2012] [Accepted: 06/21/2012] [Indexed: 02/08/2023]
Abstract
The phylogenetically ancient SLC26 gene family encodes multifunctional anion exchangers and anion channels transporting a broad range of substrates, including Cl(-), HCO3(-), sulfate, oxalate, I(-), and formate. SLC26 polypeptides are characterized by N-terminal cytoplasmic domains, 10-14 hydrophobic transmembrane spans, and C-terminal cytoplasmic STAS domains, and appear to be homo-oligomeric. SLC26-related SulP proteins of marine bacteria likely transport HCO3(-) as part of oceanic carbon fixation. SulP genes present in antibiotic operons may provide sulfate for antibiotic biosynthetic pathways. SLC26-related Sultr proteins transport sulfate in unicellular eukaryotes and in plants. Mutations in three human SLC26 genes are associated with congenital or early onset Mendelian diseases: chondrodysplasias for SLC26A2, chloride diarrhea for SLC26A3, and deafness with enlargement of the vestibular aqueduct for SLC26A4. Additional disease phenotypes evident only in mouse knockout models include oxalate urolithiasis for Slc26a6 and Slc26a1, non-syndromic deafness for Slc26a5, gastric hypochlorhydria for Slc26a7 and Slc26a9, distal renal tubular acidosis for Slc26a7, and male infertility for Slc26a8. STAS domains are required for cell surface expression of SLC26 proteins, and contribute to regulation of the cystic fibrosis transmembrane regulator in complex, cell- and tissue-specific ways. The protein interactomes of SLC26 polypeptides are under active investigation.
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Affiliation(s)
- Seth L Alper
- Renal Division and Division of Molecular and Vascular Medicine, Beth Israel Deaconess Medical Center, Boston, MA 02215, USA.
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26
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Hell M, Bernhofer C, Stalzer P, Kern JM, Claassen E. Probiotics in Clostridium difficile infection: reviewing the need for a multistrain probiotic. Benef Microbes 2013; 4:39-51. [PMID: 23434948 DOI: 10.3920/bm2012.0049] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
In the past two years an enormous amount of molecular, genetic, metabolomic and mechanistic data on the host-bacterium interaction, a healthy gut microbiota and a possible role for probiotics in Clostridium difficile infection (CDI) has been accumulated. Also, new hypervirulent strains of C. difficile have emerged. Yet, clinical trials in CDI have been less promising than in antibiotic associated diarrhoea in general, with more meta-analysis than primary papers on CDI-clinical-trials. The fact that C. difficile is a spore former, producing at least three different toxins has not yet been incorporated in the rational design of probiotics for (recurrent) CDI. Here we postulate that the plethora of effects of C. difficile and the vast amount of data on the role of commensal gut residents and probiotics point towards a multistrain mixture of probiotics to reduce CDI, but also to limit (nosocomial) transmission and/or endogenous reinfection. On the basis of a retrospective chart review of a series of ten CDI patients where recurrence was expected, all patients on adjunctive probiotic therapy with multistrain cocktail (Ecologic®AAD/OMNiBiOTiC® 10) showed complete clinical resolution. This result, and recent success in faecal transplants in CDI treatment, are supportive for the rational design of multistrain probiotics for CDI.
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Affiliation(s)
- M Hell
- Department of Hospital Epidemiology and Infection Control, Salzburg University Hospital, Paracelsus Medical University, Strubergasse 21, 5020 Salzburg, Austria
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27
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Roginiel AC, Kohut DL, Kaur S, Saleh AMA, Weber T, Geibel P, Singh H, Geibel JP. Effect of NSAIDs on Na⁺/H⁺ exchanger activity in rat colonic crypts. Am J Physiol Cell Physiol 2013; 305:C512-8. [PMID: 23739181 DOI: 10.1152/ajpcell.00303.2012] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Nonsteroidal anti-inflammatory drugs (NSAIDs; 1) are widely recommended for several acute and chronic conditions. For example, both indomethacin and aspirin are taken for pain relief. Aspirin is also used for prevention of myocardial infarction, and indomethacin can be administered orally or as a suppository for patients with rheumatoid disease and other chronic inflammatory states. However, use of NSAIDs can cause damage to the mucosal barrier surrounding the gastrointestinal (GI) tract, increasing the risk of ulcer formation. While microencapsulation of NSAIDs has been shown to reduce upper GI injury, sustained release in the lower GI tract and colon may cause epithelial erosion due to increased acidification. The use of suppositories has also been linked to rectal and lower GI bleeding. In this study, we investigated the role of NSAIDs aspirin and indomethacin on Na⁺/H⁺ exchanger (NHE) activity in rat colonic crypts. By comparing average rates of pH recovery between control and NSAID perfusion runs, we were able to determine that both aspirin and indomethacin increase hydrogen extrusion into the colonic lumen. Through treatment with 5-ethylisopropyl amiloride (EIPA), amiloride, and zoniporide dihydrochloride, we further demonstrated that indomethacin specifically enhances proton excretion through regulation of apical NHE-3 and NHE-2 and to a lesser extent on basolateral NHE-1 and NHE-4. Our results suggest that clinical exposure to NSAIDs may affect colonic tissue at the site of selected NHE isoforms, resulting in modulation of transport and barrier function.
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Affiliation(s)
- Aliya C Roginiel
- Department of Surgery, Yale University School of Medicine, New Haven, Connecticut, USA
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28
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Differential expression of Na+/H+-exchanger (NHE-1, 2, and 4) proteins and mRNA in rodent's uterus under sex steroid effect and at different phases of the oestrous cycle. BIOMED RESEARCH INTERNATIONAL 2013; 2013:840121. [PMID: 23509787 PMCID: PMC3582097 DOI: 10.1155/2013/840121] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/14/2012] [Accepted: 01/01/2013] [Indexed: 12/16/2022]
Abstract
Precise uterine fluid pH regulation may involve the Na+/H+-exchanger (NHE). We hypothesized that NHE isoforms are differentially expressed under different sex steroid treatment and at different oestrous cycle phases which may explain the uterine fluid pH changes observed under these conditions. Method. Oestrous cycle phases of intact WKY rats were identified by vaginal smear. Another group of rats was ovariectomized and treated with 0.2 μg 17β-oestradiol (E), 4 mg progesterone (P), and E followed by P (E + P). The animals were then sacrificed and the uteri were removed for mRNA and protein expression analyses by real-time PCR and western blotting, respectively. NHE isoforms distribution was detected by immunohistochemistry (IHC). Results. NHE-1 mRNA and protein were upregulated at diestrus (Ds) and following P treatment. Meanwhile, NHE-2 and NHE-4 proteins and mRNA were upregulated at proestrus (Ps) and estrus (Es) and following E treatment. NHE-1 was found predominantly at the apical membrane, while NHE-2 and NHE-4 were found at the apical and basolateral membranes of the luminal epithelia. NHE-4 is the main isoform upregulated by E. Conclusion. Differential expressions of uterine NHE isoforms 1, 2, and 4 could explain the observed changes in the uterine fluid pH under these conditions.
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Gill RK, Kumar A, Malhotra P, Maher D, Singh V, Dudeja PK, Alrefai W, Saksena S. Regulation of intestinal serotonin transporter expression via epigenetic mechanisms: role of HDAC2. Am J Physiol Cell Physiol 2012. [PMID: 23195070 DOI: 10.1152/ajpcell.00361.2012] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
The serotonin (5-HT) transporter (SERT) facilitates clearance of extracellular 5-HT by its uptake and internalization. Decreased expression of SERT and consequent high 5-HT levels have been implicated in various diarrheal disorders. Thus, appropriate regulation of SERT is critical for maintenance of 5-HT homeostasis in health and disease. Previous studies demonstrated that SERT is regulated via posttranslational and transcriptional mechanisms. However, the role of epigenetic mechanisms in SERT regulation is not known. Current studies investigated the effects of histone deacetylase (HDAC) inhibition on SERT expression and delineated the mechanisms. Treatment of Caco-2 cells with the pan-HDAC inhibitors butyrate (5 mM) and trichostatin (TSA, 1 μM) decreased SERT mRNA and protein levels. Butyrate- or TSA-induced decrease in SERT was associated with decreased activity of human SERT (hSERT) promoter 1 (upstream of exon 1a), but not hSERT promoter 2 (upstream of exon 2). Butyrate + TSA did not show an additive effect on SERT expression, indicating that mechanisms involving histone hyperacetylation may be involved. Chromatin immunoprecipitation assays demonstrated enrichment of the hSERT promoter 1 (flanking nt -250/+2) with tetra-acetylated histone H3 or H4, which was increased (~3-fold) by butyrate. Interestingly, specific inhibition of HDAC2 (but not HDAC1) utilizing small interfering RNA decreased SERT mRNA and protein levels. The decrease in SERT expression by HDAC inhibition was recapitulated in an in vivo model. SERT mRNA levels were decreased in the ileum and colon of mice fed pectin (increased availability of butyrate) compared with controls fed a fiber-free diet (~50-60%). Our results identify a novel role of HDAC2 as a regulator of SERT gene expression in intestinal epithelial cells.
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Affiliation(s)
- Ravinder K Gill
- Section of Digestive Diseases and Nutrition, Department of Medicine, University of Illinois at Chicago, Chicago, IL 60612, USA.
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Rocafull MA, Thomas LE, del Castillo JR. The second sodium pump: from the function to the gene. Pflugers Arch 2012; 463:755-77. [PMID: 22543357 PMCID: PMC3350626 DOI: 10.1007/s00424-012-1101-3] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2012] [Revised: 03/22/2012] [Accepted: 03/24/2012] [Indexed: 11/30/2022]
Abstract
Transepithelial Na(+) transport is mediated by passive Na(+) entry across the luminal membrane and exit through the basolateral membrane by two active mechanisms: the Na(+)/K(+) pump and the second sodium pump. These processes are associated with the ouabain-sensitive Na(+)/K(+)-ATPase and the ouabain-insensitive, furosemide-inhibitable Na(+)-ATPase, respectively. Over the last 40 years, the second sodium pump has not been successfully associated with any particular membrane protein. Recently, however, purification and cloning of intestinal α-subunit of the Na(+)-ATPase from guinea pig allowed us to define it as a unique biochemical and molecular entity. The Na(+)- and Na(+)/K(+)-ATPase genes are at the same locus, atp1a1, but have independent promoters and some different exons. Herein, we spotlight the functional characteristics of the second sodium pump, and the associated Na(+)-ATPase, in the context of its role in transepithelial transport and its response to a variety of physiological and pathophysiological conditions. Identification of the Na(+)-ATPase gene (atna) allowed us, using a bioinformatics approach, to explore the tertiary structure of the protein in relation to other P-type ATPases and to predict regulatory sites in the promoter region. Potential regulatory sites linked to inflammation and cellular stress were identified in the atna gene. In addition, a human atna ortholog was recognized. Finally, experimental data obtained using spontaneously hypertensive rats suggest that the Na(+)-ATPase could play a role in the pathogenesis of essential hypertension. Thus, the participation of the second sodium pump in transepithelial Na(+) transport and cellular Na(+) homeostasis leads us to reconsider its role in health and disease.
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Affiliation(s)
- Miguel A. Rocafull
- Laboratorio de Fisiología Molecular, Centro de Biofísica y Bioquímica, Instituto Venezolano de Investigaciones Científicas (IVIC), Apartado 20632, Caracas, 1020A Venezuela
| | - Luz E. Thomas
- Laboratorio de Fisiología Molecular, Centro de Biofísica y Bioquímica, Instituto Venezolano de Investigaciones Científicas (IVIC), Apartado 20632, Caracas, 1020A Venezuela
| | - Jesús R. del Castillo
- Laboratorio de Fisiología Molecular, Centro de Biofísica y Bioquímica, Instituto Venezolano de Investigaciones Científicas (IVIC), Apartado 20632, Caracas, 1020A Venezuela
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Abstract
PURPOSE OF REVIEW 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. RECENT FINDINGS Knockout of NHERF1 and NHERF2 allowed translation of the data largely derived from the in-vitro models into a living organism. These studies also expand our knowledge about the complexity of intestinal transporter interactomes, define the role for scaffolding proteins in basal and regulated apical transport, and help identify potential targets for pharmacological approaches. We continue to accumulate novel information about the function and regulation of NHE3 (including its role in regulating paracellular Ca2+ flux), NHE8, as well as about the complexity of the intestinal Cl- and HCO3- transport in health and disease. SUMMARY Thanks to the new genetically engineered mouse models, a significant progress has been made in our understanding of the role of NHERF proteins in regulation of intestinal Na+ absorption. Significant novel data on the coordinated function of bicarbonate, chloride, and sodium transporters contributes to our current views of the integrative physiology of the small intestinal electrolyte transport.
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