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Bhardwaj A, Münch A, Montague J, Koch S, Rosenstiel P, Escudero‐Hernández C. Lymphocytic colitis can be transcriptionally divided into channelopathic and inflammatory lymphocytic colitis. United European Gastroenterol J 2024; 12:737-748. [PMID: 38366868 PMCID: PMC11250513 DOI: 10.1002/ueg2.12531] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/06/2023] [Accepted: 11/19/2023] [Indexed: 02/18/2024] Open
Abstract
BACKGROUND The pathobiology of the non-destructive inflammatory bowel disease (IBD) lymphocytic colitis (LC) is poorly understood. We aimed to define an LC-specific mucosal transcriptome to gain insight into LC pathology, identify unique genomic signatures, and uncover potentially druggable disease pathways. METHODS We performed bulk RNA-sequencing of LC and collagenous colitis (CC) colonic mucosa from patients with active disease, and healthy controls (n = 4-10 per cohort). Differential gene expression was analyzed by gene-set enrichment and deconvolution analyses to identify pathologically relevant pathways and cells, respectively, altered in LC. Key findings were validated using reverse transcription quantitative PCR and/or immunohistochemistry. Finally, we compared our data with a previous cohort of ulcerative colitis and Crohn's disease patients (n = 4 per group) to distinguish non-destructive from classic IBD. RESULTS LC can be subdivided into channelopathic LC, which is governed by organic acid and ion transport dysregulation, and inflammatory LC, which is driven by microbial immune responses. Inflammatory LC displays an innate and adaptive immunity that is limited compared to CC and classic IBD. Conversely, we noted a distinct induction of regulatory non-coding RNA species in inflammatory LC samples. Moreover, compared with CC, water channel and cell adhesion molecule gene expression decreased in channelopathic LC, whereas it was accentuated in inflammatory LC and associated with reduced intestinal epithelial cell proliferation. CONCLUSIONS We conclude that LC can be subdivided into channelopathic LC and inflammatory LC that could be pathomechanistically distinct subtypes despite their shared clinical presentation. Inflammatory LC exhibits a dampened immune response compared to CC and classic IBDs. Our results point to regulatory micro-RNAs as a potential disease-specific feature that may be amenable to therapeutic intervention.
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MESH Headings
- Humans
- Colitis, Lymphocytic/genetics
- Colitis, Lymphocytic/immunology
- Intestinal Mucosa/immunology
- Intestinal Mucosa/pathology
- Intestinal Mucosa/metabolism
- Transcriptome
- Female
- Colitis, Collagenous/immunology
- Colitis, Collagenous/genetics
- Colitis, Collagenous/pathology
- Colitis, Collagenous/diagnosis
- Crohn Disease/immunology
- Crohn Disease/genetics
- Crohn Disease/pathology
- Crohn Disease/diagnosis
- Male
- Colon/immunology
- Colon/pathology
- Middle Aged
- Case-Control Studies
- Gene Expression Profiling
- Colitis, Ulcerative/immunology
- Colitis, Ulcerative/genetics
- Colitis, Ulcerative/pathology
- Colitis, Ulcerative/diagnosis
- Adult
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Affiliation(s)
- Archana Bhardwaj
- Institute of Clinical Molecular Biology (IKMB)Christian‐Albrechts‐University and University Hospital Schleswig‐HolsteinKielGermany
| | - Andreas Münch
- Department of Biomedical and Clinical Sciences (BKV)Linköping UniversityLinköpingSweden
- Department of Gastroenterology and HepatologyLinköping UniversityLinköpingSweden
- Department of Health, Medicine, and Caring SciencesLinköping UniversityLinköpingSweden
| | - Julia Montague
- Institute of Clinical Molecular Biology (IKMB)Christian‐Albrechts‐University and University Hospital Schleswig‐HolsteinKielGermany
| | - Stefan Koch
- Department of Biomedical and Clinical Sciences (BKV)Linköping UniversityLinköpingSweden
- Wallenberg Centre for Molecular Medicine (WCMM)Linköping UniversityLinköpingSweden
| | - Philip Rosenstiel
- Institute of Clinical Molecular Biology (IKMB)Christian‐Albrechts‐University and University Hospital Schleswig‐HolsteinKielGermany
| | - Celia Escudero‐Hernández
- Institute of Clinical Molecular Biology (IKMB)Christian‐Albrechts‐University and University Hospital Schleswig‐HolsteinKielGermany
- Department of Biomedical and Clinical Sciences (BKV)Linköping UniversityLinköpingSweden
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Awad K, Barmeyer C, Bojarski C, Nagel O, Lee IFM, Schweiger MR, Schulzke JD, Bücker R. Epithelial Barrier Dysfunction in Diarrhea-Predominant Irritable Bowel Syndrome (IBS-D) via Downregulation of Claudin-1. Cells 2023; 12:2846. [PMID: 38132165 PMCID: PMC10741936 DOI: 10.3390/cells12242846] [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: 11/20/2023] [Revised: 12/05/2023] [Accepted: 12/07/2023] [Indexed: 12/23/2023] Open
Abstract
BACKGROUND In patients with diarrhea-predominant irritable bowel syndrome (IBS-D), the diarrheal mechanisms are largely unknown, and they were examined in this study on colon biopsies. METHODS Electrophysiological measurements were used for monitoring functional changes in the diarrheic colon specimens. In parallel, tight junction protein expression was analyzed by Western blot and confocal laser-scanning microscopy, and signaling pathway analysis was performed using RNA sequencing and bioinformatics. RESULTS Epithelial resistance was decreased, indicating an epithelial leak flux diarrheal mechanism with a molecular correlate of decreased claudin-1 expression, while induction of active anion secretion and impairment of active sodium absorption via the epithelial sodium channel, ENaC, were not detected. The pathway analysis revealed activation of barrier-affecting cytokines TNF-α, IFN-γ, IL-1β and IL-4. CONCLUSIONS Barrier dysfunction as a result of epithelial tight junction changes plays a role in IBS-D as a pathomechanism inducing a leak flux type of diarrhea.
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Affiliation(s)
- Karem Awad
- Clinical Physiology/Nutritional Medicine, Department of Gastroenterology, Infectious Diseases and Rheumatology, Charité—Universitätsmedizin Berlin, Campus Benjamin Franklin, 12203 Berlin, Germany (O.N.)
| | - Christian Barmeyer
- Clinical Physiology/Nutritional Medicine, Department of Gastroenterology, Infectious Diseases and Rheumatology, Charité—Universitätsmedizin Berlin, Campus Benjamin Franklin, 12203 Berlin, Germany (O.N.)
| | - Christian Bojarski
- Clinical Physiology/Nutritional Medicine, Department of Gastroenterology, Infectious Diseases and Rheumatology, Charité—Universitätsmedizin Berlin, Campus Benjamin Franklin, 12203 Berlin, Germany (O.N.)
| | - Oliver Nagel
- Clinical Physiology/Nutritional Medicine, Department of Gastroenterology, Infectious Diseases and Rheumatology, Charité—Universitätsmedizin Berlin, Campus Benjamin Franklin, 12203 Berlin, Germany (O.N.)
| | - In-Fah M. Lee
- Clinical Physiology/Nutritional Medicine, Department of Gastroenterology, Infectious Diseases and Rheumatology, Charité—Universitätsmedizin Berlin, Campus Benjamin Franklin, 12203 Berlin, Germany (O.N.)
| | - Michal R. Schweiger
- Institute for Translational Epigenetics, Medical Faculty, University of Cologne, 50931 Cologne, Germany
| | - Jörg-Dieter Schulzke
- Clinical Physiology/Nutritional Medicine, Department of Gastroenterology, Infectious Diseases and Rheumatology, Charité—Universitätsmedizin Berlin, Campus Benjamin Franklin, 12203 Berlin, Germany (O.N.)
| | - Roland Bücker
- Clinical Physiology/Nutritional Medicine, Department of Gastroenterology, Infectious Diseases and Rheumatology, Charité—Universitätsmedizin Berlin, Campus Benjamin Franklin, 12203 Berlin, Germany (O.N.)
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Chen Y, Yu X, Yan Z, Zhang S, Zhang J, Guo W. Role of epithelial sodium channel-related inflammation in human diseases. Front Immunol 2023; 14:1178410. [PMID: 37559717 PMCID: PMC10407551 DOI: 10.3389/fimmu.2023.1178410] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2023] [Accepted: 06/29/2023] [Indexed: 08/11/2023] Open
Abstract
The epithelial sodium channel (ENaC) is a heterotrimer and is widely distributed throughout the kidneys, blood vessels, lungs, colons, and many other organs. The basic role of the ENaC is to mediate the entry of Na+ into cells; the ENaC also has an important regulatory function in blood pressure, airway surface liquid (ASL), and endothelial cell function. Aldosterone, serum/glucocorticoid kinase 1 (SGK1), shear stress, and posttranslational modifications can regulate the activity of the ENaC; some ion channels also interact with the ENaC. In recent years, it has been found that the ENaC can lead to immune cell activation, endothelial cell dysfunction, aggravated inflammation involved in high salt-induced hypertension, cystic fibrosis, pseudohypoaldosteronism (PHA), and tumors; some inflammatory cytokines have been reported to have a regulatory role on the ENaC. The ENaC hyperfunction mediates the increase of intracellular Na+, and the elevated exchange of Na+ with Ca2+ leads to an intracellular calcium overload, which is an important mechanism for ENaC-related inflammation. Some of the research on the ENaC is controversial or unclear; we therefore reviewed the progress of studies on the role of ENaC-related inflammation in human diseases and their mechanisms.
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Affiliation(s)
- Yabin Chen
- Department of Hepatobiliary and Pancreatic Surgery, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, China
- National Organ Transplantation (Liver &Kidney Transplantation) Physician Training Centre, Zhengzhou, China
- National Regional Medical Treatment Centre of Henan Organ Transplantation, Zhengzhou, China
| | - Xiao Yu
- Department of Hepatobiliary and Pancreatic Surgery, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, China
- National Organ Transplantation (Liver &Kidney Transplantation) Physician Training Centre, Zhengzhou, China
- National Regional Medical Treatment Centre of Henan Organ Transplantation, Zhengzhou, China
| | - Zhiping Yan
- Henan Organ Transplantation Centre, Zhengzhou, China
- Henan Engineering and Research Center for Diagnosis and Treatment of Hepatobiliary and Pancreatic Surgical Diseases, Zhengzhou, China
| | - Shuijun Zhang
- Henan Research Centre for Organ Transplantation, Zhengzhou, China
| | - Jiacheng Zhang
- Henan Key Laboratory for Digestive Organ Transplantation, the First Affiliated Hospital of Zhengzhou University, Zhengzhou, China
| | - Wenzhi Guo
- Department of Hepatobiliary and Pancreatic Surgery, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, China
- Open and Key Laboratory for Hepatobiliary and Pancreatic Surgery and Digestive Organ Transplantation at Henan Universities, Zhengzhou, China
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Yu J, Zhao J, Xie H, Cai M, Yao L, Li J, Han L, Chen W, Yu N, Peng D. Dendrobium huoshanense polysaccharides ameliorate ulcerative colitis by improving intestinal mucosal barrier and regulating gut microbiota. J Funct Foods 2022. [DOI: 10.1016/j.jff.2022.105231] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023] Open
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Zabana Y, Tontini G, Hultgren-Hörnquist E, Skonieczna-Żydecka K, Latella G, Østvik AE, Marlicz W, D'Amato M, Arias A, Mielhke S, Münch A, Fernández-Bañares F, Lucendo AJ. Pathogenesis of Microscopic Colitis: A Systematic Review. J Crohns Colitis 2022; 16:143-161. [PMID: 34272945 DOI: 10.1093/ecco-jcc/jjab123] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
BACKGROUND Whereas the exact aetiology of microscopic colitis [MC] remains unknown, a dysregulated immune response to luminal factors or medications is the most accepted pathogenesis hypothesis. METHODS We conducted a systematic review of the pathogenesis of MC. We applied the Joanna Briggs Institute methodologies and the PRISMA statement for the reporting of systematic reviews [PROSPERO Trial Identifier: CRD42020145008]. Populations, Exposure of interest, and Outcome [PEO] questions were used to explore the following topics in MC: 1] intestinal luminal factors; 2] autoimmunity; 3] innate immunity; 4] adaptive immunity; 5] extracellular matrix; 6] genetic risk factors; and 7] mechanism of diarrhoea. A search was done in PubMed, Embase, and Web of Science up to February 2020. A narrative description was performed explaining the findings for each aspect of MC aetiopathogenesis. RESULTS Thirty-eight documents provided evidence for PEO1, 100 for PEO2, 72 for PEO3 and 4, 38 for PEO5, 20 for PEO6, and 23 for PEO7. The majority of documents were cohorts, case reports, and case series, with a few case-control and some experimental studies. Consistency among data provided by different studies was considered to support pathogenetic hypotheses. MC is a multifactorial disease believed to involve innate and adaptive immune responses to luminal factors, genetic risk, autoimmunity, and extracellular matrix alterations, all contributing by varied mechanisms to watery diarrhoea. CONCLUSIONS This is the first systematic review on the aetiology of MC supporting the notion that MC is a multifactorial disease. However, high-profile studies are lacking, and most evidence derives from small heterogeneous studies.
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Affiliation(s)
- Yamile Zabana
- Gastroenterology Department, Hospital Universitari Mútua de Terrassa, Barcelona, Spain
- Centro de Investigación Biomédica en Red de Enfermedades Hepáticas y Digestivas, Barcelona, Spain
| | - Gian Tontini
- Department of Pathophysiology and Transplantation, University of Milan and Gastroenterology and Endoscopy Unit, Fondazione IRCCS Ca'Granda Ospedale Maggiore Policlinico, Milan, Italy
| | | | | | - Giovanni Latella
- Gastroenterology Unit, Department of Life, Health and Environmental Sciences, University of L'Aquila, L'Aquila, Italy
| | - Ann Elisabeth Østvik
- Department of Clinical and Molecular Medicine [IKOM], Faculty of Medicine and Health Sciences, Norwegian University of Science and Technology, Trondheim, Norway
- Department of Gastroenterology and Hepatology, Clinic of Medicine, St. Olav's University Hospital, Trondheim, Norway
| | - Wojciech Marlicz
- Department of Gastroenterology, Pomeranian Medical University, Szczecin, Poland
- Centre for Digestive Diseases Endoklinika, Szczecin, Poland
| | - Mauro D'Amato
- Gastrointestinal Genetics Lab, CIC bioGUNE - BRTA, Derio, Spain
- Ikerbasque, Basque Foundation for Science, Bilbao, Spain
| | - Angel Arias
- Centro de Investigación Biomédica en Red de Enfermedades Hepáticas y Digestivas, Barcelona, Spain
- Research Unit, Hospital General Mancha Centro, Alcázar de San Juan, Ciudad Real, Spain
| | - Stephan Mielhke
- Centre for Digestive Diseases, Internal Medicine Centre Eppendorf & Endoscopy Centre, University Hospital Hamburg Eppendorf, Hamburg, Germany
| | - Andreas Münch
- Department of Health, Medicine, and Caring Sciences, Linköping University, Linköping, Sweden
| | - Fernando Fernández-Bañares
- Gastroenterology Department, Hospital Universitari Mútua de Terrassa, Barcelona, Spain
- Centro de Investigación Biomédica en Red de Enfermedades Hepáticas y Digestivas, Barcelona, Spain
| | - Alfredo J Lucendo
- Centro de Investigación Biomédica en Red de Enfermedades Hepáticas y Digestivas, Barcelona, Spain
- Gastroenterology Department, Hospital General de Tomelloso-Spain and Instituto de Investigación Sanitaria Princesa [IIS-IP], Madrid, Spain
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Impaired Intestinal Sodium Transport in Inflammatory Bowel Disease: From the Passenger to the Driver's Seat. Cell Mol Gastroenterol Hepatol 2021; 12:277-292. [PMID: 33744482 PMCID: PMC8165433 DOI: 10.1016/j.jcmgh.2021.03.005] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/12/2020] [Revised: 03/09/2021] [Accepted: 03/09/2021] [Indexed: 12/22/2022]
Abstract
Although impaired intestinal sodium transport has been described for decades as a ubiquitous feature of inflammatory bowel disease (IBD), whether and how it plays a pivotal role in the ailment has remained uncertain. Our identification of dominant mutations in receptor guanylyl cyclase 2C as a cause of IBD-associated familial diarrhea syndrome brought a shift in the way we envision impaired sodium transport. Is this just a passive collateral effect resulting from intestinal inflammation, or is it a crucial regulator of IBD pathogenesis? This review summarizes the mutational spectrum and underlying mechanisms of monogenic IBD associated with congenital sodium diarrhea. We constructed a model proposing that impaired sodium transport is an upstream pathogenic factor in IBD. The review also synthesized emerging insights from microbiome and animal studies to suggest how sodium malabsorption can serve as a unifying mediator of downstream pathophysiology. Further investigations into the mechanisms underlying salt and water transport in the intestine will provide newer approaches for understanding the ion-microbiome-immune cross-talk that serves as a driver of IBD. Model systems, such as patient-derived enteroids or induced pluripotent stem cell models, are warranted to unravel the role of individual genes regulating sodium transport and to develop more effective epithelial rescue and repair therapies.
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Nielsen HL, Dalager-Pedersen M, Nielsen H. High risk of microscopic colitis after Campylobacter concisus infection: population-based cohort study. Gut 2020; 69:1952-1958. [PMID: 32111632 DOI: 10.1136/gutjnl-2019-319771] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/02/2019] [Revised: 01/31/2020] [Accepted: 02/08/2020] [Indexed: 12/14/2022]
Abstract
OBJECTIVE Microscopic colitis (MC) encompasses the two histopathological distinct entities of collagenous colitis (CC) and lymphocytic colitis (LC). In this Danish population-based cohort study, we examined the risk of MC following stool culture with Campylobacter concisus, C. jejuni, non-typhoidal Salmonella or a culture-negative stool test. DESIGN We identified patients with a first-time positive stool culture with C. concisus, C. jejuni, non-typhoidal Salmonella or negative stool test, from 2009 through 2013 in North Denmark Region, Denmark, and matched each with 10 population comparisons. All subjects were followed up until 1 March 2018 using Systematised Nomenclature of Medicine codes from The Danish Pathology Register for incident diagnoses of CC and LC. We computed risk and adjusted HRs with 95% CIs for MC among patients and comparisons. RESULTS We identified 962 patients with C. concisus, 1725 with C. jejuni, 446 with Salmonella and 11 825 patients with culture-negative stools. The MC risk and HR versus comparisons were high for patients with C. concisus (risk 6.2%, HR 32.4 (95% CI 18.9 to 55.6)), less for C. jejuni (risk 0.6%, HR 3.7 (95% CI 1.8 to 7.7)), low for Salmonella (risk 0.4%, HR 2.2 (95% CI 0.5 to 10.8)) and for patients with negative stool testing (risk 3.3%, HR 19.6 (95% CI 16.4 to 23.4)). After exclusion of the first year of follow-up, the HRs were 9.3 (95% CI 4.1 to 20.1), 2.2 (95% CI 0.9 to 5.4), 1.3 (95% CI 0.2 to 11.1) and 5.6 (95% CI 4.6 to 7.2), respectively. CONCLUSION A high risk of MC was observed following C. concisus in stools. Further studies are needed to elucidate any underlying biological mechanisms.
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Affiliation(s)
- Hans Linde Nielsen
- Department of Clinical Microbiology, Aalborg University Hospital, Aalborg, Denmark .,Department of Clinical Medicine, Aalborg University, Aalborg, Denmark
| | - Michael Dalager-Pedersen
- Department of Clinical Medicine, Aalborg University, Aalborg, Denmark.,Department of Infectious Diseases, Aalborg University Hospital, Aalborg, Denmark
| | - Henrik Nielsen
- Department of Clinical Medicine, Aalborg University, Aalborg, Denmark.,Department of Infectious Diseases, Aalborg University Hospital, Aalborg, Denmark
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Escudero-Hernández C, Münch A, Østvik AE, Granlund AVB, Koch S. The Water Channel Aquaporin 8 is a Critical Regulator of Intestinal Fluid Homeostasis in Collagenous Colitis. J Crohns Colitis 2020; 14:962-973. [PMID: 32016376 PMCID: PMC7393183 DOI: 10.1093/ecco-jcc/jjaa020] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
BACKGROUND AND AIMS Diarrhoea is a common, debilitating symptom of gastrointestinal disorders. Pathomechanisms probably involve defects in trans-epithelial water transport, but the role of aquaporin [AQP] family water channels in diarrhoea-predominant diseases is unknown. We investigated the involvement of AQPs in the pathobiology of collagenous colitis [CC], which features chronic, watery diarrhoea despite overtly normal intestinal epithelial cells [IECs]. METHODS We assessed the expression of all AQP family members in mucosal samples of CC patients before and during treatment with the corticosteroid drug budesonide, steroid-refractory CC patients and healthy controls. Samples were analysed by genome-wide mRNA sequencing [RNA-seq] and quantitative real-time PCR [qPCR]. In some patients, we performed tissue microdissection followed by RNA-seq to explore the IEC-specific CC transcriptome. We determined changes in the protein levels of the lead candidates in IEC by confocal microscopy. Finally, we investigated the regulation of AQP expression by corticosteroids in model cell lines. RESULTS Using qPCR and RNA-seq, we identified loss of AQP8 expression as a hallmark of active CC, which was reverted by budesonide treatment in steroid-responsive but not refractory patients. Consistently, decreased AQP8 mRNA and protein levels were observed in IECs of patients with active CC, and steroid drugs increased AQP8 expression in model IECs. Moreover, low APQ8 expression was strongly associated with higher stool frequency in CC patients. CONCLUSION Down-regulation of epithelial AQP8 may impair water resorption in active CC, resulting in watery diarrhoea. Our results suggest that AQP8 is a potential drug target for the treatment of diarrhoeal disorders.
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Affiliation(s)
| | - Andreas Münch
- Department of Biomedical and Clinical Sciences [BKV), Linköping University, Linköping, Sweden,Division of Gastroenterology and Hepatology, Department of Biomedical and Clinical Sciences [BKV), Faculty of Health Science, Linköpings University, Linköping, Sweden,Corresponding authors: Andreas Münch, MD PhD, Division of Gastroenterology and Hepatology, Department of Biomedical and Clinical Sciences [BKV), Faculty of Health Sciences, Linköping University, Linköping, 58185, Sweden. Tel: +46 100130000; ; Stefan Koch, PhD, BKV/MII—Plan 13, s-581 83 Linköping, Sweden. Tel: +46 13 282969;
| | - Ann-Elisabet Østvik
- Department of Clinical and Molecular Medicine, Faculty of Medicine and Health Sciences, Norwegian University of Science and Technology (NTNU), Trondheim, Norway,Department of Gastroenterology and Hepatology, St Olav’s University Hospital, Trondheim, Norway,Clinic of Medicine, St Olav’s University Hospital, Trondheim, Norway
| | - Atle van Beelen Granlund
- Department of Clinical and Molecular Medicine, Faculty of Medicine and Health Sciences, Norwegian University of Science and Technology (NTNU), Trondheim, Norway,Clinic of Medicine, St Olav’s University Hospital, Trondheim, Norway,Centre of Molecular Inflammation Research, Department of Clinical and Molecular Medicine, Faculty of Medicine and Health Sciences, Norwegian University of Science and Technology (NTNU), Trondheim, Norway
| | - Stefan Koch
- Department of Biomedical and Clinical Sciences [BKV), Linköping University, Linköping, Sweden,Wallenberg Centre for Molecular Medicine (WCMM), Linköping University, Linköping, Sweden,Corresponding authors: Andreas Münch, MD PhD, Division of Gastroenterology and Hepatology, Department of Biomedical and Clinical Sciences [BKV), Faculty of Health Sciences, Linköping University, Linköping, 58185, Sweden. Tel: +46 100130000; ; Stefan Koch, PhD, BKV/MII—Plan 13, s-581 83 Linköping, Sweden. Tel: +46 13 282969;
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Ion Transport Basis of Diarrhea in a Mouse Model of Adoptive T Cell Transfer Colitis. Dig Dis Sci 2020; 65:1700-1709. [PMID: 31741140 PMCID: PMC7230007 DOI: 10.1007/s10620-019-05945-4] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/29/2019] [Accepted: 11/06/2019] [Indexed: 12/13/2022]
Abstract
BACKGROUND Diarrhea, a major pathological hallmark of inflammatory bowel disease, is characterized by a significant reduction in the expression and function of key intestinal ion transporters. The adoptive naïve CD4+ T cell transfer colitis is an immune-based, chronic colitis mouse model which resembles human Crohn's disease. Although mice with T cell transfer colitis demonstrate diarrhea, the ion transporter basis of this phenotype has not been explored. AIMS/METHODS In the current studies, we aimed to determine the mRNA and protein levels of the key NaCl transporters DRA and NHE3 along with the mRNA expression of other transporters in the inflamed intestine. RESULTS Naïve CD4+ T cells, transferred to Rag2 knockout mice, induced severe colonic inflammation characterized by histological damage and increased mRNA levels of cytokines in the colon with no effect in the ileum. Diarrheal phenotype was a key feature of the excised colons of mice where loose stools were evident. Our results demonstrated that the key chloride transporter DRA, mRNA, and protein levels were significantly reduced in the inflamed colon. However, expression of the key sodium hydrogen exchanger NHE3 was unaffected. The mRNA expression of other important transporters was also determined; in this regard, the sodium channel ENACα and the monocarboxylate transporters MCT1 and SMCT1 mRNA levels were also significantly lower compared to control mice. However, CFTR mRNA was not altered in the colon or ileum. CONCLUSIONS The studies conducted herein for the first time demonstrate the downregulation of important intestinal ion transporters in proximal and distal colon in T cell transfer colitis mouse model, providing valuable evidence for the ion transporter basis of diarrhea in this chronic model of inflammation.
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Miehlke S, Verhaegh B, Tontini GE, Madisch A, Langner C, Münch A. Microscopic colitis: pathophysiology and clinical management. Lancet Gastroenterol Hepatol 2020; 4:305-314. [PMID: 30860066 DOI: 10.1016/s2468-1253(19)30048-2] [Citation(s) in RCA: 73] [Impact Index Per Article: 18.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/11/2018] [Revised: 01/18/2019] [Accepted: 01/18/2019] [Indexed: 12/12/2022]
Abstract
Microscopic colitis is a chronic inflammatory disease of the colon that frequently causes chronic watery diarrhoea that might be accompanied by abdominal pain, nocturnal diarrhoea, urgency, and faecal incontinence. These symptoms lead to poor quality of life and increased health-care costs. Diagnosis relies on histological examination of multiple biopsy samples from the colonic mucosa, which often show no or only few abnormalities on endoscopy. Two major histological subtypes can be distinguished-collagenous colitis and lymphocytic colitis-but incomplete and variant forms with fewer characteristic features have been reported. Here we summarise the latest evidence on epidemiology, pathogenesis, and risk factors, and discuss established and novel therapeutic options for clinical remission. Finally, we propose an updated treatment algorithm. Further prospective studies are needed to clarify the natural history of microscopic colitis, supported by validated criteria for the assessment of disease activity.
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Affiliation(s)
- Stephan Miehlke
- Centre for Digestive Diseases, Internal Medicine Centre Eppendorf, Hamburg, Germany; Centre for Oesophageal Disorders, University Hospital Eppendorf, Hamburg, Germany.
| | - Bas Verhaegh
- Division of Gastroenterology-Hepatology, Department of Internal Medicine, Maastricht University Medical Centre, Maastricht, Netherlands
| | - Gian Eugenio Tontini
- Gastroenterology and Endoscopy, Foundation IRCCS Ca' Granda Ospedale Maggiore Policlinico, Milan, Italy
| | - Ahmed Madisch
- Department of Gastroenterology, CRH Clinic Siloah, Hannover, Germany
| | - Cord Langner
- Institute of Pathology, Medical University of Graz, Graz, Austria
| | - Andreas Münch
- Department of Gastroenterology, Linköping University, Linköping, Sweden
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Nattramilarasu PK, Bücker R, Lobo de Sá FD, Fromm A, Nagel O, Lee IFM, Butkevych E, Mousavi S, Genger C, Kløve S, Heimesaat MM, Bereswill S, Schweiger MR, Nielsen HL, Troeger H, Schulzke JD. Campylobacter concisus Impairs Sodium Absorption in Colonic Epithelium via ENaC Dysfunction and Claudin-8 Disruption. Int J Mol Sci 2020; 21:ijms21020373. [PMID: 31936044 PMCID: PMC7013563 DOI: 10.3390/ijms21020373] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2019] [Revised: 12/31/2019] [Accepted: 12/31/2019] [Indexed: 12/12/2022] Open
Abstract
The epithelial sodium channel (ENaC) can increase the colonic absorptive capacity for salt and water. Campylobacter concisus is a common pathogenic epsilonproteobacterium, causing enteritis and diarrhea. It can induce barrier dysfunction in the intestine, but its influence on intestinal transport function is still unknown. Therefore, our study aimed to characterize C. concisus effects on ENaC using the HT-29/B6-GR/MR (epithelial cell line HT-29/B6 transfected with glucocorticoid and mineralocorticoid receptors) cell model and mouse colon. In Ussing chambers, C. concisus infection inhibited ENaC-dependent Na+ transport as indicated by a reduction in amiloride-sensitive short circuit current (−55%, n = 15, p < 0.001). This occurred via down-regulation of β- and γ-ENaC mRNA expression and ENaC ubiquitination due to extracellular signal-regulated kinase (ERK)1/2 activation, predicted by Ingenuity Pathway Analysis (IPA). In parallel, C. concisus reduced the expression of the sealing tight junction (TJ) protein claudin-8 and induced claudin-8 redistribution off the TJ domain of the enterocytes, which facilitates the back leakage of Na+ ions into the intestinal lumen. In conclusion, C. concisus caused ENaC dysfunction via interleukin-32-regulated ERK1/2, as well as claudin-8-dependent barrier dysfunction—both of which contribute to Na+ malabsorption and diarrhea.
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Affiliation(s)
- Praveen Kumar Nattramilarasu
- Institute of Clinical Physiology/Nutritional Medicine, Medical Department, Division of Gastroenterology, Infectiology and Rheumatology, Charité—Universitätsmedizin Berlin, 12203 Berlin, Germany
| | - Roland Bücker
- Institute of Clinical Physiology/Nutritional Medicine, Medical Department, Division of Gastroenterology, Infectiology and Rheumatology, Charité—Universitätsmedizin Berlin, 12203 Berlin, Germany
| | - Fábia Daniela Lobo de Sá
- Institute of Clinical Physiology/Nutritional Medicine, Medical Department, Division of Gastroenterology, Infectiology and Rheumatology, Charité—Universitätsmedizin Berlin, 12203 Berlin, Germany
| | - Anja Fromm
- Institute of Clinical Physiology/Nutritional Medicine, Medical Department, Division of Gastroenterology, Infectiology and Rheumatology, Charité—Universitätsmedizin Berlin, 12203 Berlin, Germany
| | - Oliver Nagel
- Institute of Clinical Physiology/Nutritional Medicine, Medical Department, Division of Gastroenterology, Infectiology and Rheumatology, Charité—Universitätsmedizin Berlin, 12203 Berlin, Germany
| | - In-Fah Maria Lee
- Institute of Clinical Physiology/Nutritional Medicine, Medical Department, Division of Gastroenterology, Infectiology and Rheumatology, Charité—Universitätsmedizin Berlin, 12203 Berlin, Germany
| | - Eduard Butkevych
- Institute of Clinical Physiology/Nutritional Medicine, Medical Department, Division of Gastroenterology, Infectiology and Rheumatology, Charité—Universitätsmedizin Berlin, 12203 Berlin, Germany
| | - Soraya Mousavi
- Institute of Microbiology, Infectious Diseases and Immunology, Charité—Universitätsmedizin Berlin, Campus Benjamin Franklin, 14195 Berlin, Germany
| | - Claudia Genger
- Institute of Microbiology, Infectious Diseases and Immunology, Charité—Universitätsmedizin Berlin, Campus Benjamin Franklin, 14195 Berlin, Germany
| | - Sigri Kløve
- Institute of Microbiology, Infectious Diseases and Immunology, Charité—Universitätsmedizin Berlin, Campus Benjamin Franklin, 14195 Berlin, Germany
| | - Markus M. Heimesaat
- Institute of Microbiology, Infectious Diseases and Immunology, Charité—Universitätsmedizin Berlin, Campus Benjamin Franklin, 14195 Berlin, Germany
| | - Stefan Bereswill
- Institute of Microbiology, Infectious Diseases and Immunology, Charité—Universitätsmedizin Berlin, Campus Benjamin Franklin, 14195 Berlin, Germany
| | - Michal R. Schweiger
- Laboratory for Epigenetics and Tumour genetics, University Hospital Cologne and Centre for Molecular Medicine Cologne, 50931 Cologne, Germany
| | - Hans Linde Nielsen
- Department of Clinical Microbiology, Aalborg University Hospital, 9000 Aalborg, Denmark
- Department of Clinical Medicine, Aalborg University, 9000 Aalborg, Denmark
| | - Hanno Troeger
- Medical Department, Division of Gastroenterology, Infectiology and Rheumatology, Charité—Universitätsmedizin Berlin, 12203 Berlin, Germany
| | - Jörg-Dieter Schulzke
- Institute of Clinical Physiology/Nutritional Medicine, Medical Department, Division of Gastroenterology, Infectiology and Rheumatology, Charité—Universitätsmedizin Berlin, 12203 Berlin, Germany
- Correspondence:
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Rao MC. Physiology of Electrolyte Transport in the Gut: Implications for Disease. Compr Physiol 2019; 9:947-1023. [PMID: 31187895 DOI: 10.1002/cphy.c180011] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
We now have an increased understanding of the genetics, cell biology, and physiology of electrolyte transport processes in the mammalian intestine, due to the availability of sophisticated methodologies ranging from genome wide association studies to CRISPR-CAS technology, stem cell-derived organoids, 3D microscopy, electron cryomicroscopy, single cell RNA sequencing, transgenic methodologies, and tools to manipulate cellular processes at a molecular level. This knowledge has simultaneously underscored the complexity of biological systems and the interdependence of multiple regulatory systems. In addition to the plethora of mammalian neurohumoral factors and their cross talk, advances in pyrosequencing and metagenomic analyses have highlighted the relevance of the microbiome to intestinal regulation. This article provides an overview of our current understanding of electrolyte transport processes in the small and large intestine, their regulation in health and how dysregulation at multiple levels can result in disease. Intestinal electrolyte transport is a balance of ion secretory and ion absorptive processes, all exquisitely dependent on the basolateral Na+ /K+ ATPase; when this balance goes awry, it can result in diarrhea or in constipation. The key transporters involved in secretion are the apical membrane Cl- channels and the basolateral Na+ -K+ -2Cl- cotransporter, NKCC1 and K+ channels. Absorption chiefly involves apical membrane Na+ /H+ exchangers and Cl- /HCO3 - exchangers in the small intestine and proximal colon and Na+ channels in the distal colon. Key examples of our current understanding of infectious, inflammatory, and genetic diarrheal diseases and of constipation are provided. © 2019 American Physiological Society. Compr Physiol 9:947-1023, 2019.
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Affiliation(s)
- Mrinalini C Rao
- Department of Physiology and Biophysics, University of Illinois at Chicago, Chicago, Illinois, USA
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Bücker R, Krug SM, Moos V, Bojarski C, Schweiger MR, Kerick M, Fromm A, Janßen S, Fromm M, Hering NA, Siegmund B, Schneider T, Barmeyer C, Schulzke JD. Campylobacter jejuni impairs sodium transport and epithelial barrier function via cytokine release in human colon. Mucosal Immunol 2018; 11:575-577. [PMID: 29091080 DOI: 10.1038/mi.2017.78] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
This corrects the article DOI: 10.1038/mi.2017.66.
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Campylobacter jejuni impairs sodium transport and epithelial barrier function via cytokine release in human colon. Mucosal Immunol 2018; 11:474-485. [PMID: 28766554 DOI: 10.1038/mi.2017.66] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2016] [Accepted: 06/13/2017] [Indexed: 02/04/2023]
Abstract
Campylobacter jejuni is the most prevalent cause of foodborne bacterial enteritis worldwide. Patients present with diarrhea and immune responses lead to complications like arthritis and irritable bowel syndrome. Although studies exist in animal and cell models, we aimed at a functional and structural characterization of intestinal dysfunction and the involved regulatory mechanisms in human colon. First, in patients' colonic biopsies, sodium malabsorption was identified as an important diarrheal mechanism resulting from hampered epithelial ion transport via impaired epithelial sodium channel (ENaC) β- and γ-subunit. In addition, barrier dysfunction from disrupted epithelial tight junction proteins (claudin-1, -3, -4, -5, and -8), epithelial apoptosis, and appearance of lesions was detected, which cause leak-flux diarrhea and can perpetuate immune responses. Importantly, these effects in human biopsies either represent direct action of Campylobacter jejuni (ENaC impairment) or are caused by proinflammatory signaling (barrier dysfunction). This was revealed by regulator analysis from RNA-sequencing (cytometric bead array-checked) and confirmed in cell models, which identified interferon-γ, TNFα, IL-13, and IL-1β. Finally, bioinformatics' predictions yielded additional information on protective influences like vitamin D, which was confirmed in cell models. Thus, these are candidates for intervention strategies against C. jejuni infection and post-infectious sequelae, which result from the permissive barrier defect along the leaky gut.
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Barmeyer C, Erko I, Awad K, Fromm A, Bojarski C, Meissner S, Loddenkemper C, Kerick M, Siegmund B, Fromm M, Schweiger MR, Schulzke JD. Epithelial barrier dysfunction in lymphocytic colitis through cytokine-dependent internalization of claudin-5 and -8. J Gastroenterol 2017; 52:1090-1100. [PMID: 28138755 DOI: 10.1007/s00535-017-1309-2] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/18/2016] [Accepted: 01/12/2017] [Indexed: 02/04/2023]
Abstract
BACKGROUND Watery diarrhea is the cardinal symptom of lymphocytic colitis (LC). We have previously shown that colonic Na malabsorption is one of the major pathologic alterations of LC and found evidence for an epithelial barrier defect. On these grounds, this study aimed to identify the inherent mechanisms of this epithelial barrier dysfunction and its regulatory features. METHODS Epithelial resistance (R epi) was determined by one-path impedance spectroscopy and 3H-mannitol fluxes were performed on biopsies from sigmoid colon in miniaturized Ussing chambers. Tight junction proteins were analyzed by Western blot and confocal microscopy. Inflammatory signaling was characterized in HT-29/B6 cells. Apoptosis and mucosal surface parameters were quantified morphologically. RESULTS R epi was reduced to 53% and 3H-mannitol fluxes increased 1.7-fold in LC due to lower expression of claudin-4, -5, and -8 and altered subcellular claudin-5 and -8 distributions off the tight junction. TNFα and IFNγ could mimic subcellular redistribution in HT-29/B6 cells, a process which was independent on MLCK activation. Epithelial apoptosis did not contribute to barrier dysfunction in LC and mucosal surface area was unchanged. CONCLUSIONS Epithelial barrier dysfunction in LC occurs through downregulation of claudin-4, -5, and -8, and redistribution of claudin-5 and -8 off the tight junction, which contributes to diarrhea by a leak-flux mechanism. The key effector cytokines TNFα and IFNγ turned out to be the trigger for redistribution of claudin-5 and -8. Thus, alongside sodium malabsorption, leak-flux is yet another important diarrheal mechanism in LC.
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Affiliation(s)
- Christian Barmeyer
- Department of Gastroenterology, Infectious Diseases and Rheumatology, Charité, Campus Benjamin Franklin, Berlin, Germany
- Institute of Clinical Physiology, Charité, Campus Benjamin Franklin, Hindenburgdamm 30, 12203, Berlin, Germany
| | - Irene Erko
- Department of Gastroenterology, Infectious Diseases and Rheumatology, Charité, Campus Benjamin Franklin, Berlin, Germany
| | - Karem Awad
- Institute of Clinical Physiology, Charité, Campus Benjamin Franklin, Hindenburgdamm 30, 12203, Berlin, Germany
| | - Anja Fromm
- Institute of Clinical Physiology, Charité, Campus Benjamin Franklin, Hindenburgdamm 30, 12203, Berlin, Germany
| | - Christian Bojarski
- Department of Gastroenterology, Infectious Diseases and Rheumatology, Charité, Campus Benjamin Franklin, Berlin, Germany
| | - Svenja Meissner
- Department of Gastroenterology, Infectious Diseases and Rheumatology, Charité, Campus Benjamin Franklin, Berlin, Germany
| | - Christoph Loddenkemper
- Institute of Pathology, Charité, Campus Benjamin Franklin, Berlin, Germany
- Institute of Pathology PathoTres, Berlin, Germany
| | - Martin Kerick
- Max Planck Institute for Molecular Genetics, Berlin, Germany
| | - Britta Siegmund
- Department of Gastroenterology, Infectious Diseases and Rheumatology, Charité, Campus Benjamin Franklin, Berlin, Germany
| | - Michael Fromm
- Institute of Clinical Physiology, Charité, Campus Benjamin Franklin, Hindenburgdamm 30, 12203, Berlin, Germany
| | - Michal R Schweiger
- Max Planck Institute for Molecular Genetics, Berlin, Germany
- Cologne Center for Genomics, University of Cologne, Cologne, Germany
| | - Jörg-Dieter Schulzke
- Department of Gastroenterology, Infectious Diseases and Rheumatology, Charité, Campus Benjamin Franklin, Berlin, Germany.
- Institute of Clinical Physiology, Charité, Campus Benjamin Franklin, Hindenburgdamm 30, 12203, Berlin, Germany.
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Camilleri M, Sellin JH, Barrett KE. Pathophysiology, Evaluation, and Management of Chronic Watery Diarrhea. Gastroenterology 2017; 152:515-532.e2. [PMID: 27773805 PMCID: PMC5285476 DOI: 10.1053/j.gastro.2016.10.014] [Citation(s) in RCA: 77] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/22/2016] [Revised: 09/21/2016] [Accepted: 10/11/2016] [Indexed: 02/08/2023]
Abstract
Chronic watery diarrhea poses a diagnostic and therapeutic challenge and is often a disabling condition for patients. Although acute diarrhea is likely to be caused by infection, the causes of chronic diarrhea (>4 weeks in duration) are more elusive. We review the pathophysiology, diagnosis, and treatment of chronic diarrhea. Drawing on recent insights into the molecular mechanisms of intestinal epithelial transport and barrier function, we discuss how diarrhea can result from a decrease in luminal solute absorption, an increase in secretion, or both, as well as derangements in barrier properties. We also describe the various extraepithelial factors that activate diarrheal mechanisms. Finally, clinical evaluation and tests used in the assessment of patients presenting with chronic diarrhea are reviewed, and an algorithm guiding therapeutic decisions and pharmacotherapy is presented.
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Affiliation(s)
- Michael Camilleri
- Clinical Enteric Neuroscience Translational and Epidemiological Research, Division of Gastroenterology and Hepatology, Department of Medicine, Mayo Clinic, Rochester, Minnesota.
| | - Joseph H. Sellin
- Division of Gastroenterology, Department of Medicine, Baylor College of Medicine, Houston, TX
| | - Kim E. Barrett
- Division of Gastroenterology, Department of Medicine, University of California, San Diego, La Jolla, CA
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Barmeyer C, Fromm M, Schulzke JD. Active and passive involvement of claudins in the pathophysiology of intestinal inflammatory diseases. Pflugers Arch 2016; 469:15-26. [PMID: 27904960 DOI: 10.1007/s00424-016-1914-6] [Citation(s) in RCA: 59] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2016] [Revised: 11/20/2016] [Accepted: 11/22/2016] [Indexed: 12/18/2022]
Abstract
Intestinal inflammatory diseases, four of which are discussed here, are associated with alterations of claudins. In ulcerative colitis, diarrhea and antigen entry into the mucosa occurs. Claudin-2 is upregulated but data on other claudins are still limited or vary (e.g., claudin-1 and -4). Apart from that, tight junction changes contribute to diarrhea via a leak flux mechanism, while protection against antigen entry disappears behind epithelial gross lesions (erosions) and apoptotic foci. Crohn's disease is additionally characterized by a claudin-5 and claudin-8 reduction which plays an active role in antigen uptake already before gross lesions appear. In microscopic colitis (MC), upregulation of claudin-2 expression is weak and a reduction in claudin-4 may be only passively involved, while sodium malabsorption represents the main diarrheal mechanism. However, claudin-5 is removed from MC tight junctions which may be an active trigger for inflammation through antigen uptake along the so-called leaky gut concept. In celiac disease, primary barrier defects are discussed in the context of candidate genes as PARD3 which regulate cell polarity and tight junctions. The loss of claudin-5 allows small antigens to invade, while the reductions in others like claudin-3 are rather passive events. Taken together, the specific role of single tight junction proteins for the onset and perpetuation of inflammation and the recovery from these diseases is far from being fully understood and is clearly dependent on the stage of the disease, the background of the other tight junction components, the transport activity of the mucosa, and the presence of other barrier features like gross lesions, an orchestral interplay which is discussed in this article.
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Affiliation(s)
- Christian Barmeyer
- Institute of Clinical Physiology, Charité-Universitätsmedizin Berlin, 12203, Berlin, Germany
| | - Michael Fromm
- Institute of Clinical Physiology, Charité-Universitätsmedizin Berlin, 12203, Berlin, Germany
| | - Jörg-Dieter Schulzke
- Institute of Clinical Physiology, Charité-Universitätsmedizin Berlin, 12203, Berlin, Germany.
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Guagnozzi D, Landolfi S, Vicario M. Towards a new paradigm of microscopic colitis: Incomplete and variant forms. World J Gastroenterol 2016; 22:8459-8471. [PMID: 27784958 PMCID: PMC5064027 DOI: 10.3748/wjg.v22.i38.8459] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/29/2016] [Revised: 08/20/2016] [Accepted: 09/08/2016] [Indexed: 02/06/2023] Open
Abstract
Microscopic colitis (MC) is a chronic inflammatory bowel disease that has emerged in the last three decades as a leading cause of chronic watery diarrhoea. MC classically includes two main subtypes: lymphocytic colitis (LC) and collagenous colitis (CC). Other types of histopathological changes in the colonic mucosa have been described in patients with chronic diarrhoea, without fulfilling the conventional histopathological criteria for MC diagnosis. Whereas those unclassified alterations remained orphan for a long time, the use of the term incomplete MC (MCi) is nowadays universally accepted. However, it is still unresolved whether CC, LC and MCi should be considered as one clinical entity or if they represent three related conditions. In contrast to classical MC, the real epidemiological impact of MCi remains unknown, because only few epidemiological studies and case reports have been described. MCi presents clinical characteristics indistinguishable from complete MC with a good response to budesonide and cholestiramine. Although a number of medical treatments have been assayed in MC patients, currently, there is no causal treatment approach for MC and MCi, and only empirical strategies have been performed. Further studies are needed in order to identify their etiopathogenic mechanisms, and to better classify and treat MC.
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