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Bertolini A, Nguyen M, Zehra SA, Taleb SA, Bauer-Pisani T, Palm N, Strazzabosco M, Fiorotto R. Prominent role of gut dysbiosis in the pathogenesis of cystic fibrosis-related liver disease in mice. J Hepatol 2024; 81:429-440. [PMID: 38554847 PMCID: PMC11347101 DOI: 10.1016/j.jhep.2024.03.041] [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: 07/20/2023] [Revised: 03/15/2024] [Accepted: 03/20/2024] [Indexed: 04/02/2024]
Abstract
BACKGROUND & AIMS Cystic fibrosis-related liver disease (CFLD) is a chronic cholangiopathy that increases morbidity and mortality in patients with CF. Current treatments are unsatisfactory, and incomplete understanding of CFLD pathogenesis hampers therapeutic development. We have previously shown that mouse CF cholangiocytes respond to lipopolysaccharide with excessive inflammation. Thus, we investigated the role of the gut-liver axis in the pathogenesis of CFLD. METHODS Wild-type (WT), whole-body Cftr knockout (CFTR-KO) and gut-corrected (CFTR-KO-GC) mice were studied. Liver changes were assessed by immunohistochemistry and single-cell transcriptomics (single-cell RNA sequencing), inflammatory mediators were analysed by proteome array, faecal microbiota by 16S ribosomal RNA sequencing and gut permeability by FITC-dextran assay. RESULTS The livers of CFTR-KO mice showed ductular proliferation and periportal inflammation, whereas livers of CFTR-KO-GC mice had no evident pathology. Single-cell RNA sequencing analysis of periportal cells showed increased presence of neutrophils, macrophages and T cells, and activation of pro-inflammatory and pathogen-mediated immune pathways in CFTR-KO livers, consistent with a response to gut-derived stimuli. CFTR-KO mice exhibited gut dysbiosis with enrichment of Enterobacteriaceae and Enterococcus spp., which was associated with increased intestinal permeability and mucosal inflammation, whereas gut dysbiosis and inflammation were absent in CFTR-KO-GC mice. Treatment with nonabsorbable antibiotics ameliorated intestinal permeability and liver inflammation in CFTR-KO mice. Faecal microbiota transfer from CFTR-KO to germ-free WT mice did not result in dysbiosis nor liver pathology, indicating that defective intestinal CFTR is required to maintain dysbiosis. CONCLUSION Defective CFTR in the gut sustains a pathogenic microbiota, creates an inflammatory milieu, and alters intestinal permeability. These changes are necessary for the development of cholangiopathy. Restoring CFTR in the intestine or modulating the microbiota could be a promising strategy to prevent or attenuate liver disease. IMPACT AND IMPLICATIONS Severe cystic fibrosis-related liver disease (CFLD) affects 10% of patients with cystic fibrosis (CF) and contributes to increased morbidity and mortality. Treatment options remain limited due to a lack of understanding of disease pathophysiology. The cystic fibrosis transmembrane conductance regulator (CFTR) mediates Cl- and HCO3- secretion in the biliary epithelium and its defective function is thought to cause cholestasis and excessive inflammatory responses in CF. However, our study in Cftr-knockout mice demonstrates that microbial dysbiosis, combined with increased intestinal permeability caused by defective CFTR in the intestinal mucosa, acts as a necessary co-factor for the development of CFLD-like liver pathology in mice. These findings uncover a major role for the gut microbiota in CFLD pathogenesis and call for further investigation and clinical validation to develop targeted therapeutic strategies acting on the gut-liver axis in CF.
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Affiliation(s)
- Anna Bertolini
- Department of Internal Medicine, Section of Digestive Diseases, Yale Liver Center, Yale School of Medicine, New Haven, USA
| | - Mytien Nguyen
- Department of Immunobiology, Yale School of Medicine, New Haven, USA
| | - Syeda Andleeb Zehra
- Department of Internal Medicine, Section of Digestive Diseases, Yale Liver Center, Yale School of Medicine, New Haven, USA
| | - Shakila Afroz Taleb
- Department of Internal Medicine, Section of Digestive Diseases, Yale Liver Center, Yale School of Medicine, New Haven, USA
| | - Tory Bauer-Pisani
- Department of Internal Medicine, Section of Digestive Diseases, Yale Liver Center, Yale School of Medicine, New Haven, USA
| | - Noah Palm
- Department of Immunobiology, Yale School of Medicine, New Haven, USA
| | - Mario Strazzabosco
- Department of Internal Medicine, Section of Digestive Diseases, Yale Liver Center, Yale School of Medicine, New Haven, USA
| | - Romina Fiorotto
- Department of Internal Medicine, Section of Digestive Diseases, Yale Liver Center, Yale School of Medicine, New Haven, USA.
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Islam D, Israr I, Taleb MAB, Rao A, Yosief R, Sultana R, Sampaziotis F, Tysoe OC, Trauner M, Karpen SJ, Ghanekar A, Kamath BM. A novel model to study mechanisms of cholestasis in human cholangiocytes reveals a role for the SIPR2 pathway. Hepatol Commun 2024; 8:e0389. [PMID: 38407207 PMCID: PMC10898671 DOI: 10.1097/hc9.0000000000000389] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/31/2023] [Accepted: 12/09/2023] [Indexed: 02/27/2024] Open
Abstract
BACKGROUND Ductular reactivity is central to the pathophysiology of cholangiopathies. Mechanisms underlying the reactive phenotype activation by exogenous inflammatory mediators and bile acids are poorly understood. METHODS Using human extrahepatic cholangiocyte organoids (ECOs) we developed an injury model emulating the cholestatic microenvironment with exposure to inflammatory mediators and various pathogenic bile acids. Moreover, we explored roles for the bile acid activated Sphingosine-1-phosphate receptor 2 (S1PR2) and potential beneficial effects of therapeutic bile acids UDCA and norUDCA. RESULTS Synergistic exposure to bile acids (taurocholic acid, glycocholic acid, glycochenodeoxycholic acid) and TNF-α for 24 hours induced a reactive state as measured by ECO diameter, proliferation, lactate dehydrogenase activity and reactive phenotype markers. While NorUDCA and UDCA treatments given 8 hours after injury induction both suppressed reactive phenotype activation and most injury parameters, proliferation was improved by NorUDCA only. Extrahepatic cholangiocyte organoid stimulation with S1PR2 agonist sphingosine-1-phosphate reproduced the cholangiocyte reactive state and upregulated S1PR2 downstream mediators; these effects were suppressed by S1PR2 antagonist JET-013 (JET), downstream mediator extracellular signal-regulated kinase 1/2 inhibitor, and by norUDCA or UDCA treatments. JET also partially suppressed reactive phenotype after bile acid injury. CONCLUSIONS We developed a novel model to study the reactive cholangiocyte state in response to pathological stimuli in cholestasis and demonstrated a contributory role of S1PR2 signaling in both injury and NorUDCA/UDCA treatments. This model is a valuable tool to further explore the pathophysiology of human cholangiopathies.
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Affiliation(s)
- Diana Islam
- Development & Stem Cell Biology program, Peter Gilligan Centre for Research and Learning, The Hospital for Sick Children, Toronto, Ontario, Canada
| | - Izza Israr
- Development & Stem Cell Biology program, Peter Gilligan Centre for Research and Learning, The Hospital for Sick Children, Toronto, Ontario, Canada
| | - Mohamed A. B. Taleb
- Development & Stem Cell Biology program, Peter Gilligan Centre for Research and Learning, The Hospital for Sick Children, Toronto, Ontario, Canada
| | - Aditya Rao
- Development & Stem Cell Biology program, Peter Gilligan Centre for Research and Learning, The Hospital for Sick Children, Toronto, Ontario, Canada
| | - Robel Yosief
- Development & Stem Cell Biology program, Peter Gilligan Centre for Research and Learning, The Hospital for Sick Children, Toronto, Ontario, Canada
| | - Rukhsar Sultana
- Development & Stem Cell Biology program, Peter Gilligan Centre for Research and Learning, The Hospital for Sick Children, Toronto, Ontario, Canada
| | - Fotios Sampaziotis
- Wellcome–MRC Cambridge Stem Cell Institute, Department of Medicine, University of Cambridge, Cambridge, Cambridgeshire, UK
- Department of Medicine, University of Cambridge, Cambridge, Cambridgeshire, UK
| | - Olivia C. Tysoe
- Wellcome–MRC Cambridge Stem Cell Institute, Department of Medicine, University of Cambridge, Cambridge, Cambridgeshire, UK
| | - Michael Trauner
- Hans Popper Laboratory of Molecular Hepatology, Department of Internal Medicine III, Division of Gastroenterology and Hepatology, Medical University of Vienna, Vienna, Austria
| | - Saul J. Karpen
- Division of Pediatric Gastroenterology, Department of Pediatrics, Hepatology, and Nutrition, Children’s Healthcare of Atlanta and Emory University School of Medicine, Atlanta, Georgia, USA
| | - Anand Ghanekar
- Division of General Surgery, Department of Surgery, University Health Network & The Hospital for Sick Children, University of Toronto, Toronto, Ontario, Canada
| | - Binita M. Kamath
- Development & Stem Cell Biology program, Peter Gilligan Centre for Research and Learning, The Hospital for Sick Children, Toronto, Ontario, Canada
- Division of Gastroenterology, Hepatology and Nutrition, Department of Pediatrics, The Hospital for Sick Children and the University of Toronto, Toronto, Canada
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3
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Truong JK, Li J, Li Q, Pachura K, Rao A, Gumber S, Fuchs CD, Feranchak AP, Karpen SJ, Trauner M, Dawson PA. Active enterohepatic cycling is not required for the choleretic actions of 24-norUrsodeoxycholic acid in mice. JCI Insight 2023; 8:e149360. [PMID: 36787187 PMCID: PMC10070106 DOI: 10.1172/jci.insight.149360] [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] [Subscribe] [Scholar Register] [Received: 03/08/2021] [Accepted: 02/07/2023] [Indexed: 02/15/2023] Open
Abstract
The pronounced choleretic properties of 24-norUrsodeoxycholic acid (norUDCA) to induce bicarbonate-rich bile secretion have been attributed to its ability to undergo cholehepatic shunting. The goal of this study was to identify the mechanisms underlying the choleretic actions of norUDCA and the role of the bile acid transporters. Here, we show that the apical sodium-dependent bile acid transporter (ASBT), organic solute transporter-α (OSTα), and organic anion transporting polypeptide 1a/1b (OATP1a/1b) transporters are dispensable for the norUDCA stimulation of bile flow and biliary bicarbonate secretion. Chloride channels in biliary epithelial cells provide the driving force for biliary secretion. In mouse large cholangiocytes, norUDCA potently stimulated chloride currents that were blocked by siRNA silencing and pharmacological inhibition of calcium-activated chloride channel transmembrane member 16A (TMEM16A) but unaffected by ASBT inhibition. In agreement, blocking intestinal bile acid reabsorption by coadministration of an ASBT inhibitor or bile acid sequestrant did not impact norUDCA stimulation of bile flow in WT mice. The results indicate that these major bile acid transporters are not directly involved in the absorption, cholehepatic shunting, or choleretic actions of norUDCA. Additionally, the findings support further investigation of the therapeutic synergy between norUDCA and ASBT inhibitors or bile acid sequestrants for cholestatic liver disease.
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Affiliation(s)
- Jennifer K. Truong
- Department of Pediatrics, Division of Pediatric Gastroenterology, Hepatology and Nutrition, Emory University School of Medicine, Children’s Healthcare of Atlanta, Atlanta, Georgia, USA
| | - Jianing Li
- Department of Pediatrics, Division of Pediatric Gastroenterology, Hepatology and Nutrition, Emory University School of Medicine, Children’s Healthcare of Atlanta, Atlanta, Georgia, USA
| | - Qin Li
- Department of Pediatrics, University of Pittsburgh Medical Center Children’s Hospital of Pittsburgh, Pittsburgh, Pennsylvania, USA
| | - Kimberly Pachura
- Department of Pediatrics, Division of Pediatric Gastroenterology, Hepatology and Nutrition, Emory University School of Medicine, Children’s Healthcare of Atlanta, Atlanta, Georgia, USA
| | - Anuradha Rao
- Department of Pediatrics, Division of Pediatric Gastroenterology, Hepatology and Nutrition, Emory University School of Medicine, Children’s Healthcare of Atlanta, Atlanta, Georgia, USA
| | - Sanjeev Gumber
- Division of Pathology and Laboratory Medicine, Yerkes National Research Center, Emory University School of Medicine, Atlanta, Georgia, USA
| | - Claudia Daniela Fuchs
- Hans Popper Laboratory of Molecular Hepatology, Division of Gastroenterology and Hepatology, Department of Internal Medicine III, Medical University of Vienna, Vienna, Austria
| | - Andrew P. Feranchak
- Department of Pediatrics, University of Pittsburgh Medical Center Children’s Hospital of Pittsburgh, Pittsburgh, Pennsylvania, USA
| | - Saul J. Karpen
- Department of Pediatrics, Division of Pediatric Gastroenterology, Hepatology and Nutrition, Emory University School of Medicine, Children’s Healthcare of Atlanta, Atlanta, Georgia, USA
| | - Michael Trauner
- Hans Popper Laboratory of Molecular Hepatology, Division of Gastroenterology and Hepatology, Department of Internal Medicine III, Medical University of Vienna, Vienna, Austria
| | - Paul A. Dawson
- Department of Pediatrics, Division of Pediatric Gastroenterology, Hepatology and Nutrition, Emory University School of Medicine, Children’s Healthcare of Atlanta, Atlanta, Georgia, USA
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4
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Nardo AD, Schneeweiss‐Gleixner M, Bakail M, Dixon ED, Lax SF, Trauner M. Pathophysiological mechanisms of liver injury in COVID-19. Liver Int 2021; 41:20-32. [PMID: 33190346 PMCID: PMC7753756 DOI: 10.1111/liv.14730] [Citation(s) in RCA: 234] [Impact Index Per Article: 78.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/23/2020] [Revised: 11/05/2020] [Accepted: 11/06/2020] [Indexed: 02/06/2023]
Abstract
The recent outbreak of coronavirus disease 2019 (COVID-19), caused by the Severe Acute Respiratory Syndrome Coronavirus-2 (SARS-CoV-2) has resulted in a world-wide pandemic. Disseminated lung injury with the development of acute respiratory distress syndrome (ARDS) is the main cause of mortality in COVID-19. Although liver failure does not seem to occur in the absence of pre-existing liver disease, hepatic involvement in COVID-19 may correlate with overall disease severity and serve as a prognostic factor for the development of ARDS. The spectrum of liver injury in COVID-19 may range from direct infection by SARS-CoV-2, indirect involvement by systemic inflammation, hypoxic changes, iatrogenic causes such as drugs and ventilation to exacerbation of underlying liver disease. This concise review discusses the potential pathophysiological mechanisms for SARS-CoV-2 hepatic tropism as well as acute and possibly long-term liver injury in COVID-19.
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Affiliation(s)
- Alexander D. Nardo
- Hans Popper Laboratory of Molecular HepatologyDivision of Gastroenterology and HepatologyDepartment of Internal Medicine IIIMedical University of ViennaViennaAustria
| | - Mathias Schneeweiss‐Gleixner
- Medical Intensive Care Unit 13H1. Division of Gastroenterology and HepatologyDepartment of Internal Medicine IIIMedical University of ViennaViennaAustria
| | - May Bakail
- Campus ITInstitute of Science and Technology AustriaKlosterneuburgAustria
| | - Emmanuel D. Dixon
- Hans Popper Laboratory of Molecular HepatologyDivision of Gastroenterology and HepatologyDepartment of Internal Medicine IIIMedical University of ViennaViennaAustria
| | - Sigurd F. Lax
- Department of PathologyHospital Graz IIAcademic Teaching Hospital of the Medical University of GrazGrazAustria
- School of MedicineJohannes Kepler UniversityLinzAustria
| | - Michael Trauner
- Hans Popper Laboratory of Molecular HepatologyDivision of Gastroenterology and HepatologyDepartment of Internal Medicine IIIMedical University of ViennaViennaAustria
- Medical Intensive Care Unit 13H1. Division of Gastroenterology and HepatologyDepartment of Internal Medicine IIIMedical University of ViennaViennaAustria
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5
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Nardo AD, Schneeweiss-Gleixner M, Bakail M, Dixon ED, Lax SF, Trauner M. Pathophysiological mechanisms of liver injury in COVID-19. LIVER INTERNATIONAL : OFFICIAL JOURNAL OF THE INTERNATIONAL ASSOCIATION FOR THE STUDY OF THE LIVER 2020. [PMID: 33190346 DOI: 10.1111/liv.14730.] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
The recent outbreak of coronavirus disease 2019 (COVID-19), caused by the Severe Acute Respiratory Syndrome Coronavirus-2 (SARS-CoV-2) has resulted in a world-wide pandemic. Disseminated lung injury with the development of acute respiratory distress syndrome (ARDS) is the main cause of mortality in COVID-19. Although liver failure does not seem to occur in the absence of pre-existing liver disease, hepatic involvement in COVID-19 may correlate with overall disease severity and serve as a prognostic factor for the development of ARDS. The spectrum of liver injury in COVID-19 may range from direct infection by SARS-CoV-2, indirect involvement by systemic inflammation, hypoxic changes, iatrogenic causes such as drugs and ventilation to exacerbation of underlying liver disease. This concise review discusses the potential pathophysiological mechanisms for SARS-CoV-2 hepatic tropism as well as acute and possibly long-term liver injury in COVID-19.
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Affiliation(s)
- Alexander D Nardo
- Hans Popper Laboratory of Molecular Hepatology, Division of Gastroenterology and Hepatology, Department of Internal Medicine III, Medical University of Vienna, Vienna, Austria
| | - Mathias Schneeweiss-Gleixner
- Medical Intensive Care Unit 13H1. Division of Gastroenterology and Hepatology, Department of Internal Medicine III, Medical University of Vienna, Vienna, Austria
| | - May Bakail
- Campus IT, Institute of Science and Technology Austria, Klosterneuburg, Austria
| | - Emmanuel D Dixon
- Hans Popper Laboratory of Molecular Hepatology, Division of Gastroenterology and Hepatology, Department of Internal Medicine III, Medical University of Vienna, Vienna, Austria
| | - Sigurd F Lax
- Department of Pathology, Hospital Graz II, Academic Teaching Hospital of the Medical University of Graz, Graz, Austria.,School of Medicine, Johannes Kepler University, Linz, Austria
| | - Michael Trauner
- Hans Popper Laboratory of Molecular Hepatology, Division of Gastroenterology and Hepatology, Department of Internal Medicine III, Medical University of Vienna, Vienna, Austria.,Medical Intensive Care Unit 13H1. Division of Gastroenterology and Hepatology, Department of Internal Medicine III, Medical University of Vienna, Vienna, Austria
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6
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Kriegermeier A, Green R. Pediatric Cholestatic Liver Disease: Review of Bile Acid Metabolism and Discussion of Current and Emerging Therapies. Front Med (Lausanne) 2020; 7:149. [PMID: 32432119 PMCID: PMC7214672 DOI: 10.3389/fmed.2020.00149] [Citation(s) in RCA: 35] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2019] [Accepted: 04/06/2020] [Indexed: 02/06/2023] Open
Abstract
Cholestatic liver diseases are a significant cause of morbidity and mortality and the leading indication for pediatric liver transplant. These include diseases such as biliary atresia, Alagille syndrome, progressive intrahepatic cholestasis entities, ductal plate abnormalities including Caroli syndrome and congenital hepatic fibrosis, primary sclerosing cholangitis, bile acid synthesis defects, and certain metabolic disease. Medical management of these patients typically includes supportive care for complications of chronic cholestasis including malnutrition, pruritus, and portal hypertension. However, there are limited effective interventions to prevent progressive liver damage in these diseases, leaving clinicians to ultimately rely on liver transplantation in many cases. Agents such as ursodeoxycholic acid, bile acid sequestrants, and rifampicin have been mainstays of treatment for years with the understanding that they may decrease or alter the composition of the bile acid pool, though clinical response to these medications is frequently insufficient and their effects on disease progression remain limited. Recently, animal and human studies have identified potential new therapeutic targets which may disrupt the enterohepatic circulation of bile acids, alter the expression of bile acid transporters or decrease the production of bile acids. In this article, we will review bile formation, bile acid signaling, and the relevance for current and newer therapies for pediatric cholestasis. We will also highlight further areas of potential targets for medical intervention for pediatric cholestatic liver diseases.
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Affiliation(s)
- Alyssa Kriegermeier
- Division of Gastroenterology, Hepatology and Nutrition, Department of Pediatrics, Feinberg School of Medicine, Ann & Robert H. Lurie Children's Hospital of Chicago, Northwestern University, Chicago, IL, United States
| | - Richard Green
- Division of Gastroenterology and Hepatology, Department of Internal Medicine, Feinberg School of Medicine, Northwestern University, Chicago, IL, United States
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Li Q, Kresge C, Boggs K, Scott J, Feranchak A. Mechanosensor transient receptor potential vanilloid member 4 (TRPV4) regulates mouse cholangiocyte secretion and bile formation. Am J Physiol Gastrointest Liver Physiol 2020; 318:G277-G287. [PMID: 31760763 PMCID: PMC7052575 DOI: 10.1152/ajpgi.00176.2019] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
Mechanosensitive signaling has emerged as a mechanism for the regulation of cholangiocyte transport and bile formation. The mechanical effect of fluid-flow, or shear, at the apical membrane of cholangiocytes regulates secretion through a process involving increases in [Ca2+]i and activation of Ca2+-activated Cl- channels. However, the initiating steps translating shear force to increases in intracellular calcium concentration ([Ca2+]i) are unknown. Transient receptor potential vanilloid member 4 (TRPV4), a nonselective cation channel present in the apical membrane of cholangiocytes, has been proposed as a potential mechanosensor. The aim of the present studies was to determine the potential role of TRPV4 in initiating mechanosensitive signaling in response to fluid-flow in cholangiocytes. TRPV4 expression was confirmed in both small and large mouse cholangiocytes. Exposure of cells to either fluid flow or specific TRPV4 pharmacological agonists rapidly increased both [Ca2+]i and membrane cation currents. Both flow- and agonist-stimulated currents displayed identical biophysical properties and were inhibited in the presence of TRPV4 antagonists or in cells after transfection with TRPV4 small interfering RNA. Transfection of mouse cholangiocytes with a TRPV4-enhanced green fluorescent protein construct increased the expression of TRPV4 and the magnitude of flow-stimulated currents. A specific TRPV4 agonist significantly increased the biliary concentration of ATP and bile flow in live mice when administered intravenously and increased ATP release from cholangiocyte monolayers when applied exogenously. The findings are consistent with a model in which activation of cholangiocyte TRPV4 translates shear force into an acute rise in membrane cation permeability, [Ca2+]i, ATP release, and bile flow. Understanding the role of mechanosensitive transport pathways may provide novel insights to modulate bile flow for the treatment of cholestatic liver disorders.NEW & NOTEWORTHY These studies functionally characterize TRPV4 as a mechanosensitive channel in mouse cholangiocytes. By mediating a rapid rise in intracellular Ca2+, necessary for Ca2+-dependent secretion, TRPV4 represents a mechanosensor responsible for translating fluid flow into intracellular signaling and biliary secretion. Furthermore, intravenous infusion of a specific TRPV4 agonist increases bile flow in live mice. Understanding the role of TRPV4 in mechanosensitive transport pathways may provide novel insights to modulate bile flow during cholestasis.
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Affiliation(s)
- Qin Li
- 1Department of Physiology, Jianghan University School of Medicine, Wuhan, China,3Department of Pediatrics, University of Pittsburgh Medical Center, Pittsburgh, Pennsylvania
| | - Charles Kresge
- 2Department of Pediatrics, University of Texas Southwestern Medical Center, Dallas, Texas
| | - Kristy Boggs
- 3Department of Pediatrics, University of Pittsburgh Medical Center, Pittsburgh, Pennsylvania
| | - Julie Scott
- 3Department of Pediatrics, University of Pittsburgh Medical Center, Pittsburgh, Pennsylvania
| | - Andrew Feranchak
- 3Department of Pediatrics, University of Pittsburgh Medical Center, Pittsburgh, Pennsylvania
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Type 3 inositol 1,4,5-trisphosphate receptor: A calcium channel for all seasons. Cell Calcium 2019; 85:102132. [PMID: 31790953 DOI: 10.1016/j.ceca.2019.102132] [Citation(s) in RCA: 32] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2019] [Revised: 11/21/2019] [Accepted: 11/22/2019] [Indexed: 12/18/2022]
Abstract
Inositol 1,4,5 trisphosphate receptors (ITPRs) are a family of endoplasmic reticulum Ca2+ channels essential for the control of intracellular Ca2+ levels in virtually every mammalian cell type. The three isoforms (ITPR1, ITPR2 and ITPR3) are highly homologous in amino acid sequence, but they differ considerably in terms of biophysical properties, subcellular localization, and tissue distribution. Such differences underscore the variety of cellular responses triggered by each isoform and suggest that the expression/activity of specific isoforms might be linked to particular pathophysiological states. Indeed, recent findings demonstrate that changes in expression of ITPR isoforms are associated with a number of human diseases ranging from fatty liver disease to cancer. ITPR3 is emerging as the isoform that is particularly important in the pathogenesis of various human diseases. Here we review the physiological and pathophysiological roles of ITPR3 in various tissues and the mechanisms by which the expression of this isoform is modulated in health and disease.
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Fiorotto R, Strazzabosco M. Pathophysiology of Cystic Fibrosis Liver Disease: A Channelopathy Leading to Alterations in Innate Immunity and in Microbiota. Cell Mol Gastroenterol Hepatol 2019; 8:197-207. [PMID: 31075352 PMCID: PMC6664222 DOI: 10.1016/j.jcmgh.2019.04.013] [Citation(s) in RCA: 33] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/13/2019] [Revised: 04/24/2019] [Accepted: 04/24/2019] [Indexed: 12/12/2022]
Abstract
Cystic fibrosis (CF) is a monogenic disease caused by mutation of Cftr. CF-associated liver disease (CFLD) is a common nonpulmonary cause of mortality in CF and accounts for approximately 2.5%-5% of overall CF mortality. The peak of the disease is in the pediatric population, but a second wave of liver disease in CF adults has been reported in the past decade in association with an increase in the life expectancy of these patients. New drugs are available to correct the basic defect in CF but their efficacy in CFLD is not known. The cystic fibrosis transmembrane conductance regulator, expressed in the apical membrane of cholangiocytes, is a major determinant for bile secretion and CFLD classically has been considered a channelopathy. However, the recent findings of the cystic fibrosis transmembrane conductance regulator as a regulator of epithelial innate immunity and the possible influence of the intestinal disease with an altered microbiota on the liver complication have opened new mechanistic insights on the pathogenesis of CFLD. This review provides an overview of the current understanding of the pathophysiology of the disease and discusses a potential target for intervention.
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Affiliation(s)
- Romina Fiorotto
- Section of Digestive Diseases, Yale Liver Center, Department of Internal Medicine, Yale School of Medicine, New Haven, Connecticut.
| | - Mario Strazzabosco
- Section of Digestive Diseases, Yale Liver Center, Department of Internal Medicine, Yale School of Medicine, New Haven, Connecticut
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Cholangiocyte death in ductopenic cholestatic cholangiopathies: Mechanistic basis and emerging therapeutic strategies. Life Sci 2019; 218:324-339. [DOI: 10.1016/j.lfs.2018.12.044] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2018] [Accepted: 12/26/2018] [Indexed: 02/07/2023]
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11
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Franca A, Filho ACML, Guerra MT, Weerachayaphorn J, dos Santos ML, Njei B, Robert M, Lima CX, Vidigal PVT, Banales JM, Ananthanarayanam M, Leite MF, Nathanson MH. Effects of Endotoxin on Type 3 Inositol 1,4,5-Trisphosphate Receptor in Human Cholangiocytes. Hepatology 2019; 69:817-830. [PMID: 30141207 PMCID: PMC6351171 DOI: 10.1002/hep.30228] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/11/2018] [Accepted: 08/13/2018] [Indexed: 12/16/2022]
Abstract
Clinical conditions that result in endotoxemia, such as sepsis and alcoholic hepatitis (AH), often are accompanied by cholestasis. Although hepatocellular changes in response to lipopolysaccharide (LPS) have been well characterized, less is known about whether and how cholangiocytes contribute to this form of cholestasis. We examined effects of endotoxin on expression and function of the type 3 inositol trisphosphate receptor (ITPR3), because this is the main intracellular Ca2+ release channel in cholangiocytes, and loss of it impairs ductular bicarbonate secretion. Bile duct cells expressed the LPS receptor, Toll-like receptor 4 (TLR4), which links to activation of nuclear factor-κB (NF-κB). Analysis of the human ITPR3 promoter revealed five putative response elements to NF-κB, and promoter activity was inhibited by p65/p50. Nested 0.5- and 1.0-kilobase (kb) deletion fragments of the ITPR3 promoter were inhibited by NF-κB subunits. Chromatin immunoprecipitation (ChIP) assay showed that NF-κB interacts with the ITPR3 promoter, with an associated increase in H3K9 methylation. LPS decreased ITPR3 mRNA and protein expression and also decreased sensitivity of bile duct cells to calcium agonist stimuli. This reduction was reversed by inhibition of TLR4. ITPR3 expression was decreased or absent in cholangiocytes from patients with cholestasis of sepsis and from those with severe AH. Conclusion: Stimulation of TLR4 by LPS activates NF-κB to down-regulate ITPR3 expression in human cholangiocytes. This may contribute to the cholestasis that can be observed in conditions such as sepsis or AH.
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Affiliation(s)
- Andressa Franca
- Federal University of Minas Gerais (UFMG), Belo Horizonte, MG
| | | | - Mateus T. Guerra
- Section of Digestive Disease, Department of Internal Medicine, Yale University School of Medicine, New Haven, CT
| | - Jittima Weerachayaphorn
- Section of Digestive Disease, Department of Internal Medicine, Yale University School of Medicine, New Haven, CT,Department of Physiology, Faculty of Science, Mahidol University, Bangkok, Thailand
| | | | - Basile Njei
- Section of Digestive Disease, Department of Internal Medicine, Yale University School of Medicine, New Haven, CT
| | - Marie Robert
- Department of Pathology, Yale University School of Medicine, New Haven, CT
| | | | | | - Jesus M. Banales
- Department of Liver and Gastrointestinal Diseases, Biodonostia Research Institute, Donostia University Hospital, University of the Basque Country (UPV/EHU), San Sebastian, Spain
| | | | - M. Fatima Leite
- Federal University of Minas Gerais (UFMG), Belo Horizonte, MG
| | - Michael H. Nathanson
- Section of Digestive Disease, Department of Internal Medicine, Yale University School of Medicine, New Haven, CT
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12
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Cabrera D, Arab JP, Arrese M. UDCA, NorUDCA, and TUDCA in Liver Diseases: A Review of Their Mechanisms of Action and Clinical Applications. Handb Exp Pharmacol 2019; 256:237-264. [PMID: 31236688 DOI: 10.1007/164_2019_241] [Citation(s) in RCA: 42] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Bile acids (BAs) are key molecules in generating bile flow, which is an essential function of the liver. In the last decades, there have been great advances in the understanding of BA physiology, and new insights have emerged regarding the role of BAs in determining cell damage and death in several liver diseases. This new knowledge has helped to better delineate the pathophysiology of cholestasis and the adaptive responses of hepatocytes to cholestatic liver injury as well as of the mechanisms of injury of biliary epithelia. In this context, therapeutic approaches for liver diseases using hydrophilic BA (i.e., ursodeoxycholic acid, tauroursodeoxycholic, and, more recently, norursodeoxycholic acid), have been revamped. In the present review, we summarize current experimental and clinical data regarding these BAs and its role in the treatment of certain liver diseases.
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Affiliation(s)
- Daniel Cabrera
- Departamento de Gastroenterología, Escuela de Medicina, Pontificia Universidad Católica de Chile, Santiago, Chile
- Departamento de Ciencias Químicas y Biológicas, Facultad de Salud, Universidad Bernardo O'Higgins, Santiago, Chile
| | - Juan Pablo Arab
- Departamento de Gastroenterología, Escuela de Medicina, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Marco Arrese
- Departamento de Gastroenterología, Escuela de Medicina, Pontificia Universidad Católica de Chile, Santiago, Chile.
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13
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Rodrigues MA, Gomes DA, Nathanson MH. Calcium Signaling in Cholangiocytes: Methods, Mechanisms, and Effects. Int J Mol Sci 2018; 19:ijms19123913. [PMID: 30563259 PMCID: PMC6321159 DOI: 10.3390/ijms19123913] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2018] [Revised: 11/13/2018] [Accepted: 11/20/2018] [Indexed: 02/06/2023] Open
Abstract
Calcium (Ca2+) is a versatile second messenger that regulates a number of cellular processes in virtually every type of cell. The inositol 1,4,5-trisphosphate receptor (ITPR) is the only intracellular Ca2+ release channel in cholangiocytes, and is therefore responsible for Ca2+-mediated processes in these cells. This review will discuss the machinery responsible for Ca2+ signals in these cells, as well as experimental models used to investigate cholangiocyte Ca2+ signaling. We will also discuss the role of Ca2+ in the normal and abnormal regulation of secretion and apoptosis in cholangiocytes, two of the best characterized processes mediated by Ca2+ in this cell type.
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Affiliation(s)
- Michele Angela Rodrigues
- Section of Digestive Diseases, Department of Internal Medicine, Yale University School of Medicine, 333 Cedar Street, New Haven, CT 06520-8019, USA.
| | - Dawidson Assis Gomes
- Section of Digestive Diseases, Department of Internal Medicine, Yale University School of Medicine, 333 Cedar Street, New Haven, CT 06520-8019, USA.
- Department of Biochemistry and Immunology, Federal University of Minas Gerais. Av. Antônio Carlos, 6627, Belo Horizonte-MG 31270-901, Brazil.
| | - Michael Harris Nathanson
- Section of Digestive Diseases, Department of Internal Medicine, Yale University School of Medicine, 333 Cedar Street, New Haven, CT 06520-8019, USA.
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14
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van Niekerk J, Kersten R, Beuers U. Role of Bile Acids and the Biliary HCO 3- Umbrella in the Pathogenesis of Primary Biliary Cholangitis. Clin Liver Dis 2018; 22:457-479. [PMID: 30259847 DOI: 10.1016/j.cld.2018.03.013] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
The biliary HCO3- umbrella hypothesis states that human cholangiocytes and hepatocytes create a protective apical alkaline barrier against millimolar concentrations of potentially toxic glycine-conjugated bile salts in bile by secreting HCO3- into the bile duct lumen. This alkaline barrier may retain biliary bile salts in their polar, deprotonated, and membrane-impermeant state to avoid uncontrolled invasion of apolar toxic bile acids, which initiate apoptosis, autophagy and senescence. In primary biliary cholangitis, defects of the biliary HCO3- umbrella, leading to impaired biliary HCO3- secretion have been identified. Current medical therapies stabilize the putatively defective biliary HCO3- umbrella and improve long-term prognosis.
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Affiliation(s)
- Jorrit van Niekerk
- Department of Gastroenterology and Hepatology, Tytgat Institute for Liver and Intestinal Research, Academic Medical Center, University of Amsterdam, Meibergdreef 9, Amsterdam 1105 AZ, The Netherlands
| | - Remco Kersten
- Department of Gastroenterology and Hepatology, Tytgat Institute for Liver and Intestinal Research, Academic Medical Center, University of Amsterdam, Meibergdreef 9, Amsterdam 1105 AZ, The Netherlands
| | - Ulrich Beuers
- Department of Gastroenterology and Hepatology, Tytgat Institute for Liver and Intestinal Research, Academic Medical Center, University of Amsterdam, Meibergdreef 9, Amsterdam 1105 AZ, The Netherlands.
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15
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Fiorotto R, Amenduni M, Mariotti V, Cadamuro M, Fabris L, Spirli C, Strazzabosco M. Animal models for cystic fibrosis liver disease (CFLD). Biochim Biophys Acta Mol Basis Dis 2018; 1865:965-969. [PMID: 30071276 DOI: 10.1016/j.bbadis.2018.07.026] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2018] [Revised: 07/18/2018] [Accepted: 07/19/2018] [Indexed: 12/20/2022]
Abstract
Liver disease is a severe complication in patients with Cystic Fibrosis (CF), a genetic disease caused by mutations in the gene encoding for cystic fibrosis transmembrane conductance regulator (CFTR) channel. The sequence of events leading to CFLD is still unclear and has limited the development of more specific treatments other than the bile acid UDCA. However, in the last twenty years, several gaps have been filled, which have mainly been possible due to the availability of different animal models that mimic CF. CF mice, although they lack a spontaneous liver manifestation, have been essential to better understand the multiple functions of CFTR expression on the apical membrane of cholangiocytes, from chloride channel to regulator of epithelial innate immunity. Additionally, we have learned that the gut microbiota might be a pathogenetic factor for the development of liver disease. The recent creation of novel CF animal models (i.e. pig and ferret) that better reproduce the human disease, will allow for comparative studies with species that spontaneously develop the liver disease and will hopefully lead to novel therapeutic treatments. In this review, we have compared and summarized the main features of the current available CF animal models and their applicability for the study of the liver phenotype.
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Affiliation(s)
- Romina Fiorotto
- Digestive Disease Section, Yale Liver Center, Yale University School of Medicine, New Haven, CT, USA
| | - Mariangela Amenduni
- Digestive Disease Section, Yale Liver Center, Yale University School of Medicine, New Haven, CT, USA
| | - Valeria Mariotti
- Department of Molecular Medicine, University of Padova School of Medicine, Padova, Italy
| | - Massimiliano Cadamuro
- Department of Molecular Medicine, University of Padova School of Medicine, Padova, Italy
| | - Luca Fabris
- Department of Molecular Medicine, University of Padova School of Medicine, Padova, Italy
| | - Carlo Spirli
- Digestive Disease Section, Yale Liver Center, Yale University School of Medicine, New Haven, CT, USA.
| | - Mario Strazzabosco
- Digestive Disease Section, Yale Liver Center, Yale University School of Medicine, New Haven, CT, USA
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16
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Oliva-Vilarnau N, Hankeova S, Vorrink SU, Mkrtchian S, Andersson ER, Lauschke VM. Calcium Signaling in Liver Injury and Regeneration. Front Med (Lausanne) 2018; 5:192. [PMID: 30023358 PMCID: PMC6039545 DOI: 10.3389/fmed.2018.00192] [Citation(s) in RCA: 53] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2018] [Accepted: 06/11/2018] [Indexed: 12/12/2022] Open
Abstract
The liver fulfills central roles in metabolic control and detoxification and, as such, is continuously exposed to a plethora of insults. Importantly, the liver has a unique ability to regenerate and can completely recoup from most acute, non-iterative insults. However, multiple conditions, including viral hepatitis, non-alcoholic fatty liver disease (NAFLD), long-term alcohol abuse and chronic use of certain medications, can cause persistent injury in which the regenerative capacity eventually becomes dysfunctional, resulting in hepatic scaring and cirrhosis. Calcium is a versatile secondary messenger that regulates multiple hepatic functions, including lipid and carbohydrate metabolism, as well as bile secretion and choleresis. Accordingly, dysregulation of calcium signaling is a hallmark of both acute and chronic liver diseases. In addition, recent research implicates calcium transients as essential components of liver regeneration. In this review, we provide a comprehensive overview of the role of calcium signaling in liver health and disease and discuss the importance of calcium in the orchestration of the ensuing regenerative response. Furthermore, we highlight similarities and differences in spatiotemporal calcium regulation between liver insults of different etiologies. Finally, we discuss intracellular calcium control as an emerging therapeutic target for liver injury and summarize recent clinical findings of calcium modulation for the treatment of ischemic-reperfusion injury, cholestasis and NAFLD.
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Affiliation(s)
- Nuria Oliva-Vilarnau
- Section of Pharmacogenetics, Department of Physiology and Pharmacology, Karolinska Institutet, Stockholm, Sweden
| | - Simona Hankeova
- Department of Biosciences and Nutrition, Karolinska Institutet, Huddinge, Sweden.,Faculty of Science, Institute of Experimental Biology, Masaryk University, Brno, Czechia
| | - Sabine U Vorrink
- Section of Pharmacogenetics, Department of Physiology and Pharmacology, Karolinska Institutet, Stockholm, Sweden
| | - Souren Mkrtchian
- Section of Pharmacogenetics, Department of Physiology and Pharmacology, Karolinska Institutet, Stockholm, Sweden
| | - Emma R Andersson
- Department of Biosciences and Nutrition, Karolinska Institutet, Huddinge, Sweden.,Department of Cell and Molecular Biology, Karolinska Institutet, Stockholm, Sweden
| | - Volker M Lauschke
- Section of Pharmacogenetics, Department of Physiology and Pharmacology, Karolinska Institutet, Stockholm, Sweden
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17
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Li Q, Dutta A, Kresge C, Bugde A, Feranchak AP. Bile acids stimulate cholangiocyte fluid secretion by activation of transmembrane member 16A Cl - channels. Hepatology 2018; 68:187-199. [PMID: 29360145 PMCID: PMC6055743 DOI: 10.1002/hep.29804] [Citation(s) in RCA: 36] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/21/2017] [Revised: 01/12/2018] [Accepted: 01/18/2018] [Indexed: 12/28/2022]
Abstract
UNLABELLED Bile acids stimulate a bicarbonate-rich choleresis, in part, through effects on cholangiocytes. Because Cl- channels in the apical membrane of cholangiocytes provide the driving force for secretion and transmembrane member 16A (TMEM16A) has been identified as the Ca2+ -activated Cl- channel in the apical membrane of cholangiocytes, the aim of the present study was to determine whether TMEM16A is the target of bile-acid-stimulated Cl- secretion and to identify the regulatory pathway involved. In these studies of mouse, rat, and human biliary epithelium exposure to ursodeoxycholic acid (UDCA) or tauroursodeoxycholic acid (TUDCA) rapidly increased the rate of exocytosis, ATP release, [Ca2+ ]i , membrane Cl- permeability, and transepithelial secretion. Bile-acid-stimulated Cl- currents demonstrated biophysical properties consistent with TMEM16A and were inhibited by pharmacological or molecular (small-interfering RNA; siRNA) inhibition of TMEM16A. Bile acid-stimulated Cl- currents were not observed in the presence of apyrase, suramin, or 2-aminoethoxydiphenyl borate (2-APB), demonstrating that current activation requires extracellular ATP, P2Y, and inositol 1,4,5-trisphosphate (IP3) receptors. TUDCA did not activate Cl- currents during pharmacologic inhibition of the apical Na+ -dependent bile acid transporter (ASBT), but direct intracellular delivery of TUDCA rapidly activated Cl- currents. CONCLUSION Bile acids stimulate Cl- secretion in mouse and human biliary cells through activation of membrane TMEM16A channels in a process regulated by extracellular ATP and [Ca2+ ]i . These studies suggest that TMEM16A channels may be targets to increase bile flow during cholestasis. (Hepatology 2018;68:187-199).
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Affiliation(s)
- Qin Li
- Department of PhysiologyJianghan University School of MedicineWuhanChina,Department of PediatricsUniversity of Texas Southwestern Medical CenterDallasTX
| | - Amal Dutta
- Department of PediatricsUniversity of Texas Southwestern Medical CenterDallasTX
| | - Charles Kresge
- Department of PediatricsUniversity of Texas Southwestern Medical CenterDallasTX
| | - Abhijit Bugde
- Departments of Cell BiologyUniversity of Texas Southwestern Medical CenterDallasTX
| | - Andrew P. Feranchak
- Department of PediatricsUniversity of Texas Southwestern Medical CenterDallasTX
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18
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Trampert DC, Nathanson MH. Regulation of bile secretion by calcium signaling in health and disease. BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2018; 1865:1761-1770. [PMID: 29787781 DOI: 10.1016/j.bbamcr.2018.05.010] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/27/2018] [Revised: 05/12/2018] [Accepted: 05/16/2018] [Indexed: 12/15/2022]
Abstract
Calcium (Ca2+) signaling controls secretion in many types of cells and tissues. In the liver, Ca2+ regulates secretion in both hepatocytes, which are responsible for primary formation of bile, and cholangiocytes, which line the biliary tree and further condition the bile before it is secreted. Cholestatic liver diseases, which are characterized by impaired bile secretion, may result from impaired Ca2+ signaling mechanisms in either hepatocytes or cholangiocytes. This review will discuss the Ca2+ signaling machinery and mechanisms responsible for regulation of secretion in both hepatocytes and cholangiocytes, and the pathophysiological changes in Ca2+ signaling that can occur in each of these cell types to result in cholestasis.
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Affiliation(s)
- David C Trampert
- Section of Digestive Diseases, Department of Internal Medicine, Yale University School of Medicine, 333 Cedar Street, New Haven, CT 06520-8019, USA
| | - Michael H Nathanson
- Section of Digestive Diseases, Department of Internal Medicine, Yale University School of Medicine, 333 Cedar Street, New Haven, CT 06520-8019, USA.
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19
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Feranchak AP. Cystic fibrosis transmembrane conductance regulator: Actin(g) as a master regulator of cholangiocyte function. Hepatology 2018; 67:833-836. [PMID: 29023826 DOI: 10.1002/hep.29583] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/30/2017] [Revised: 09/21/2017] [Accepted: 10/03/2017] [Indexed: 01/13/2023]
Affiliation(s)
- Andrew P Feranchak
- Department of Pediatrics, University of Texas Southwestern Medical Center, Dallas, TX
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20
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Fiorotto R, Amenduni M, Mariotti V, Fabris L, Spirli C, Strazzabosco M. Src kinase inhibition reduces inflammatory and cytoskeletal changes in ΔF508 human cholangiocytes and improves cystic fibrosis transmembrane conductance regulator correctors efficacy. Hepatology 2018; 67:972-988. [PMID: 28836688 PMCID: PMC5783790 DOI: 10.1002/hep.29400] [Citation(s) in RCA: 38] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/11/2017] [Revised: 07/18/2017] [Accepted: 07/20/2017] [Indexed: 12/15/2022]
Abstract
Cystic fibrosis transmembrane conductance regulator (CFTR), the channel mutated in cystic fibrosis (CF), is expressed by the biliary epithelium (i.e., cholangiocytes) of the liver. Progressive clinical liver disease (CF-associated liver disease; CFLD) occurs in around 10% of CF patients and represents the third leading cause of death. Impaired secretion and inflammation contribute to CFLD; however, the lack of human-derived experimental models has hampered the understanding of CFLD pathophysiology and the search for a cure. We have investigated the cellular mechanisms altered in human CF cholangiocytes using induced pluripotent stem cells (iPSCs) derived from healthy controls and a ΔF508 CFTR patient. We have devised a novel protocol for the differentiation of human iPSC into polarized monolayers of cholangiocytes. Our results show that iPSC-cholangiocytes reproduced the polarity and the secretory function of the biliary epithelium. Protein kinase A/cAMP-mediated fluid secretion was impaired in ΔF508 cholangiocytes and negligibly improved by VX-770 and VX-809, two small molecule drugs used to correct and potentiate ΔF508 CFTR. Moreover, ΔF508 cholangiocytes showed increased phosphorylation of Src kinase and Toll-like receptor 4 and proinflammatory changes, including increased nuclear factor kappa-light-chain-enhancer of activated B cells activation, secretion of proinflammatory chemokines (i.e., monocyte chemotactic protein 1 and interleukin-8), as well as alterations of the F-actin cytoskeleton. Treatment with Src inhibitor (4-amino-5-(4-chlorophenyl)-7-(t-butyl)pyrazolo[3,4-d]pyramidine) decreased the inflammatory changes and improved cytoskeletal defects. Inhibition of Src, along with administration of VX-770 and VX-809, successfully restored fluid secretion to normal levels. CONCLUSION Our findings have strong translational potential and indicate that targeting Src kinase and decreasing inflammation may increase the efficacy of pharmacological therapies aimed at correcting the basic ΔF508 defect in CF liver patients. These studies also demonstrate the promise of applying iPSC technology in modeling human cholangiopathies. (Hepatology 2018;67:972-988).
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Affiliation(s)
- Romina Fiorotto
- Section of Digestive Diseases, Liver Center, Yale University, New Haven, CT, USA
- International Center for Digestive Health, University of Milan-Bicocca, Milan, Italy
| | - Mariangela Amenduni
- Section of Digestive Diseases, Liver Center, Yale University, New Haven, CT, USA
| | - Valeria Mariotti
- Department of Molecular Medicine, University of Padua, School of Medicine, Padua, Italy
| | - Luca Fabris
- Department of Molecular Medicine, University of Padua, School of Medicine, Padua, Italy
| | - Carlo Spirli
- Section of Digestive Diseases, Liver Center, Yale University, New Haven, CT, USA
- International Center for Digestive Health, University of Milan-Bicocca, Milan, Italy
| | - Mario Strazzabosco
- Section of Digestive Diseases, Liver Center, Yale University, New Haven, CT, USA
- International Center for Digestive Health, University of Milan-Bicocca, Milan, Italy
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21
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Animal models of biliary injury and altered bile acid metabolism. Biochim Biophys Acta Mol Basis Dis 2017; 1864:1254-1261. [PMID: 28709963 DOI: 10.1016/j.bbadis.2017.06.027] [Citation(s) in RCA: 107] [Impact Index Per Article: 15.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2017] [Revised: 06/28/2017] [Accepted: 06/30/2017] [Indexed: 12/14/2022]
Abstract
In the last 25years, a number of animal models, mainly rodents, have been generated with the goal to mimic cholestatic liver injuries and, thus, to provide in vivo tools to investigate the mechanisms of biliary repair and, eventually, to test the efficacy of innovative treatments. Despite fundamental limitations applying to these models, such as the distinct immune system and the different metabolism regulating liver homeostasis in rodents when compared to humans, multiple approaches, such as surgery (bile duct ligation), chemical-induced (3,5-diethoxycarbonyl-1,4-dihydrocollidine, DDC, α-naphthylisothiocyanate, ANIT), viral infections (Rhesus rotavirustype A, RRV-A), and genetic manipulation (Mdr2, Cftr, Pkd1, Pkd2, Prkcsh, Sec63, Pkhd1) have been developed. Overall, they have led to a range of liver phenotypes recapitulating the main features of biliary injury and altered bile acid metabolisms, such as ductular reaction, peribiliary inflammation and fibrosis, obstructive cholestasis and biliary dysgenesis. Although with a limited translability to the human setting, these mouse models have provided us with the ability to probe over time the fundamental mechanisms promoting cholestatic disease progression. Moreover, recent studies from genetically engineered mice have unveiled 'core' pathways that make the cholangiocyte a pivotal player in liver repair. In this review, we will highlight the main phenotypic features, the more interesting peculiarities and the different drawbacks of these mouse models. This article is part of a Special Issue entitled: Cholangiocytes in Health and Disease edited by Jesus Banales, Marco Marzioni, Nicholas LaRusso and Peter Jansen.
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22
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Fiorotto R, Villani A, Kourtidis A, Scirpo R, Amenduni M, Geibel PJ, Cadamuro M, Spirli C, Anastasiadis PZ, Strazzabosco M. The cystic fibrosis transmembrane conductance regulator controls biliary epithelial inflammation and permeability by regulating Src tyrosine kinase activity. Hepatology 2016; 64:2118-2134. [PMID: 27629435 PMCID: PMC5115965 DOI: 10.1002/hep.28817] [Citation(s) in RCA: 49] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/02/2016] [Revised: 07/22/2016] [Accepted: 08/06/2016] [Indexed: 12/18/2022]
Abstract
UNLABELLED In the liver, the cystic fibrosis (CF) transmembrane conductance regulator (CFTR) regulates bile secretion and other functions at the apical membrane of biliary epithelial cells (i.e., cholangiocytes). CF-related liver disease is a major cause of death in patients with CF. CFTR dysfunction affects innate immune pathways, generating a para-inflammatory status in the liver and other epithelia. This study investigates the mechanisms linking CFTR to toll-like receptor 4 activity. We found that CFTR is associated with a multiprotein complex at the apical membrane of normal mouse cholangiocytes, with proteins that negatively control Rous sarcoma oncogene cellular homolog (Src) activity. In CFTR-defective cholangiocytes, Src tyrosine kinase self-activates and phosphorylates toll-like receptor 4, resulting in activation of nuclear factor kappa-light-chain-enhancer of activated B cells and increased proinflammatory cytokine production in response to endotoxins. This Src/nuclear factor kappa-light-chain-enhancer of activated B cells-dependent inflammatory process attracts inflammatory cells but also generates changes in the apical junctional complex and loss of epithelial barrier function. Inhibition of Src decreased the inflammatory response of CF cholangiocytes to lipopolysaccharide, rescued the junctional defect in vitro, and significantly attenuated endotoxin-induced biliary damage and inflammation in vivo (Cftr knockout mice). CONCLUSION These findings reveal a novel function of CFTR as a regulator of toll-like receptor 4 responses and cell polarity in biliary epithelial cells; this mechanism is pathogenetic, as shown by the protective effects of Src inhibition in vivo, and may be a novel therapeutic target in CF-related liver disease and other inflammatory cholangiopathies. (Hepatology 2016;64:2118-2134).
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Affiliation(s)
- Romina Fiorotto
- Section of Digestive Diseases, Liver Center, Yale University, New Haven, Connecticut, USA,International Center for Digestive Health, University of Milan-Bicocca, Milan Italy
| | - Ambra Villani
- Section of Digestive Diseases, Liver Center, Yale University, New Haven, Connecticut, USA
| | - Antonis Kourtidis
- Department of Cancer Biology, Mayo Clinic Comprehensive Cancer Center, Jacksonville, Florida, USA
| | - Roberto Scirpo
- Section of Digestive Diseases, Liver Center, Yale University, New Haven, Connecticut, USA
| | - Mariangela Amenduni
- Section of Digestive Diseases, Liver Center, Yale University, New Haven, Connecticut, USA
| | - Peter J. Geibel
- Department of Surgery, Yale University, New Haven, Connecticut, USA
| | - Massimilano Cadamuro
- International Center for Digestive Health, University of Milan-Bicocca, Milan Italy,Section of Digestive Diseases, Department of Medicine and Surgery, University of Milan-Bicocca, Milan, Italy
| | - Carlo Spirli
- Section of Digestive Diseases, Liver Center, Yale University, New Haven, Connecticut, USA,International Center for Digestive Health, University of Milan-Bicocca, Milan Italy
| | - Panos Z. Anastasiadis
- Department of Cancer Biology, Mayo Clinic Comprehensive Cancer Center, Jacksonville, Florida, USA
| | - Mario Strazzabosco
- Section of Digestive Diseases, Liver Center, Yale University, New Haven, Connecticut, USA,International Center for Digestive Health, University of Milan-Bicocca, Milan Italy,Section of Digestive Diseases, Department of Medicine and Surgery, University of Milan-Bicocca, Milan, Italy
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23
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Hisamoto S, Shimoda S, Harada K, Iwasaka S, Onohara S, Chong Y, Nakamura M, Bekki Y, Yoshizumi T, Ikegami T, Maehara Y, He XS, Gershwin ME, Akashi K. Hydrophobic bile acids suppress expression of AE2 in biliary epithelial cells and induce bile duct inflammation in primary biliary cholangitis. J Autoimmun 2016; 75:150-160. [PMID: 27592379 DOI: 10.1016/j.jaut.2016.08.006] [Citation(s) in RCA: 46] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2016] [Revised: 08/22/2016] [Accepted: 08/23/2016] [Indexed: 12/19/2022]
Abstract
Understanding the mechanisms of chronic inflammation in primary biliary cholangitis (PBC) is essential for successful treatment. Earlier work has demonstrated that patients with PBC have reduced expression of the anion exchanger 2 (AE2) on biliary epithelial cells (BEC) and deletion of AE2 gene has led to a PBC-like disorder in mice. To directly address the role of AE2 in preventing PBC pathogenesis, we took advantage of our ability to isolate human BEC and autologous splenic mononuclear cells (SMC). We studied the influence of hydrophobic bile acids, in particular, glycochenodeoxycholic acid (GCDC), on AE2 expression in BEC and the subsequent impact on the phenotypes of BEC and local inflammatory responses. We demonstrate herein that GCDC reduces AE2 expression in BEC through induction of reactive oxygen species (ROS), which enhances senescence of BEC. In addition, a reduction of AE2 levels by either GCDC or another AE2 inhibitor upregulates expression of CD40 and HLA-DR as well as production of IL-6, IL-8 and CXCL10 from BEC in response to toll like receptor ligands, an effect suppressed by inhibition of ROS. Importantly, reduced AE2 expression enhances the migration of autologous splenic mononuclear cells (SMC) towards BEC. In conclusion, our data highlight a key functional role of AE2 in the maintenance of the normal physiology of BEC and the pathogenic consequences of reduced AE2 expression, including abnormal intrinsic characteristics of BEC and their production of signal molecules that lead to the chronic inflammatory responses in small bile ducts.
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Affiliation(s)
- Satomi Hisamoto
- Department of Medicine and Biosystemic Science, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan.
| | - Shinji Shimoda
- Department of Medicine and Biosystemic Science, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan.
| | - Kenichi Harada
- Department of Human Pathology, Kanazawa University Graduate School of Medicine, Kanazawa, Japan.
| | - Sho Iwasaka
- Department of Medicine and Biosystemic Science, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan.
| | - Shinya Onohara
- Department of Medicine and Biosystemic Science, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan.
| | - Yong Chong
- Department of Medicine and Biosystemic Science, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan.
| | - Minoru Nakamura
- Clinical Research Center in National Hospital Organization (NHO), Nagasaki Medical Center and Department of Hepatology, Nagasaki University Graduate School of Biomedical Sciences, Omura, Japan.
| | - Yuki Bekki
- Department of Surgery and Science, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan.
| | - Tomoharu Yoshizumi
- Department of Surgery and Science, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan.
| | - Toru Ikegami
- Department of Surgery and Science, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan.
| | - Yoshihiko Maehara
- Department of Surgery and Science, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan.
| | - Xiao-Song He
- Division of Rheumatology, Allergy and Clinical Immunology, School of Medicine, University of California at Davis, Davis, CA, USA.
| | - M Eric Gershwin
- Division of Rheumatology, Allergy and Clinical Immunology, School of Medicine, University of California at Davis, Davis, CA, USA.
| | - Koichi Akashi
- Department of Medicine and Biosystemic Science, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan.
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Supplementation of ursodeoxycholic acid improves fat digestion and absorption in cystic fibrosis patients with mild liver involvement. Eur J Gastroenterol Hepatol 2016; 28:645-9. [PMID: 26882172 DOI: 10.1097/meg.0000000000000593] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
BACKGROUND Ursodeoxycholic acid (UDCA) supplementation is recommended for cystic fibrosis (CF) patients with associated liver disease. However, its effect on fat digestion and absorption is not known. MATERIALS AND METHODS In 23 patients with mild liver involvement, a C-mixed triglyceride breath test was performed on UDCA supplementation (with and without pancreatic enzymes - standard and increased dose) and after 1 month of UDCA withdrawal. Cumulative percentage dose recovery [CPDR; median (interquartile range)] has been considered to reflect lipid digestion and absorption. RESULTS The enzyme supplementation resulted in a significant CPDR improvement [0% (0-0) vs. 4.6% (0.4-6.0); P<0.00046]. With the increased dose of enzymes in 16 patients with abnormal C-mixed triglyceride breath test results and lipase dose less than 3000 U/g of fat, higher CPDR values [8.6% (5.6-12.7); P<0.000027] were observed. However, a 1-month UDCA withdrawal resulted in a significant reduction in (P<0.000031) fat digestion and absorption [2.9% (0.7-5.8)]. CONCLUSION UDCA supplementation seems to enhance lipid digestion and absorption in pancreatic insufficient CF patients with mild liver involvement. This finding points toward the potential impact of UDCA supplementation on nutritional status in CF patients with liver disease and underscores the often overlooked role of factors other than pancreatic enzymes on digestion and absorption of fats in CF.
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Li Q, Kresge C, Bugde A, Lamphere M, Park JY, Feranchak AP. Regulation of mechanosensitive biliary epithelial transport by the epithelial Na(+) channel. Hepatology 2016; 63:538-49. [PMID: 26475057 PMCID: PMC4780683 DOI: 10.1002/hep.28301] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/11/2015] [Accepted: 10/14/2015] [Indexed: 12/07/2022]
Abstract
UNLABELLED Intrahepatic biliary epithelial cells (BECs), also known as cholangiocytes, modulate the volume and composition of bile through the regulation of secretion and absorption. While mechanosensitive Cl(-) efflux has been identified as an important secretory pathway, the counterabsorptive pathways have not been identified. In other epithelial cells, the epithelial Na(+) channel (ENaC) has been identified as an important contributor to fluid absorption; however, its expression and function in BECs have not been previously studied. Our studies revealed the presence of α, β, and γ ENaC subunits in human BECs and α and γ subunits in mouse BECs. In studies of confluent mouse BEC monolayers, the ENaC contributes to the volume of surface fluid at the apical membrane during constitutive conditions. Further, functional studies using whole-cell patch clamp of single BECs demonstrated small constitutive Na(+) currents, which increased significantly in response to fluid-flow or shear. The magnitude of Na(+) currents was proportional to the shear force, displayed inward rectification and a reversal potential of +40 mV (ENa+ = +60 mV), and were abolished with removal of extracellular Na(+) (N-methyl-d-glucamine) or in the presence of amiloride. Transfection with ENaCα small interfering RNA significantly inhibited flow-stimulated Na(+) currents, while overexpression of the α subunit significantly increased currents. ENaC-mediated currents were positively regulated by proteases and negatively regulated by extracellular adenosine triphosphate. CONCLUSION These studies represent the initial characterization of mechanosensitive Na(+) currents activated by flow in biliary epithelium; understanding the role of mechanosensitive transport pathways may provide strategies to modulate the volume and composition of bile during cholestatic conditions. (Hepatology 2016;63:538-549).
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Affiliation(s)
- Qin Li
- Department of Physiology, Jianhan University School of Medicine, Wuhan, China,Pediatrics, University of Texas Southwestern Medical Center, Dallas, TX
| | - Charles Kresge
- Pediatrics, University of Texas Southwestern Medical Center, Dallas, TX
| | - Abhijit Bugde
- Departments of Cell Biology, University of Texas Southwestern Medical Center, Dallas, TX
| | - Michelle Lamphere
- Department of Pathology and Laboratory Medicine, Children’s Health, Children’s Medical Center, University of Texas Southwestern Medical Center, Dallas, TX
| | - Jason Y. Park
- Department of Pathology and Laboratory Medicine, Children’s Health, Children’s Medical Center, University of Texas Southwestern Medical Center, Dallas, TX,Pathology, University of Texas Southwestern Medical Center, Dallas, TX,Eugene McDermott Center for Human Growth and Development, University of Texas Southwestern Medical Center, Dallas, TX
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Scirpo R, Fiorotto R, Villani A, Amenduni M, Spirli C, Strazzabosco M. Stimulation of nuclear receptor peroxisome proliferator-activated receptor-γ limits NF-κB-dependent inflammation in mouse cystic fibrosis biliary epithelium. Hepatology 2015; 62. [PMID: 26199136 PMCID: PMC4618241 DOI: 10.1002/hep.28000] [Citation(s) in RCA: 96] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
UNLABELLED Cystic fibrosis-associated liver disease is a chronic cholangiopathy that negatively affects the quality of life of cystic fibrosis patients. In addition to reducing biliary chloride and bicarbonate secretion, up-regulation of toll-like receptor 4/nuclear factor kappa light-chain-enhancer of activated B cells (NF-κB)-dependent immune mechanisms plays a major role in the pathogenesis of cystic fibrosis-associated liver disease and may represent a therapeutic target. Nuclear receptors are transcription factors that regulate several intracellular functions. Some nuclear receptors, including peroxisome proliferator-activated receptor-γ (PPAR-γ), may counterregulate inflammation in a tissue-specific manner. In this study, we explored the anti-inflammatory effect of PPAR-γ stimulation in vivo in cystic fibrosis transmembrane conductance regulator (Cftr) knockout mice exposed to dextran sodium sulfate and in vitro in primary cholangiocytes isolated from wild-type and from Cftr-knockout mice exposed to lipopolysaccharide. We found that in CFTR-defective biliary epithelium expression of PPAR-γ is increased but that this does not result in increased receptor activity because the availability of bioactive ligands is reduced. Exogenous administration of synthetic agonists of PPAR-γ (pioglitazone and rosiglitazone) up-regulates PPAR-γ-dependent genes, while inhibiting the activation of NF-κB and the secretion of proinflammatory cytokines (lipopolysaccharide-induced CXC chemokine, monocyte chemotactic protein-1, macrophage inflammatory protein-2, granulocyte colony-stimulating factor, keratinocyte chemoattractant) in response to lipopolysaccharide. PPAR-γ agonists modulate NF-κB-dependent inflammation by up-regulating nuclear factor of kappa light polypeptide gene enhancer in B cells inhibitor alpha, a negative regulator of NF-κB. Stimulation of PPAR-γ in vivo (rosiglitazone) significantly attenuates biliary damage and inflammation in Cftr-knockout mice exposed to a dextran sodium sulfate-induced portal endotoxemia. CONCLUSION These studies unravel a novel function of PPAR-γ in controlling biliary epithelium inflammation and suggest that impaired activation of PPAR-γ contributes to the chronic inflammatory state of CFTR-defective cholangiocytes.
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Affiliation(s)
- Roberto Scirpo
- Section of Digestive Diseases, Liver Center, Yale University, New Haven, Connecticut,Department of Surgery and Translational Medicine, University of Milano-Bicocca, Milan, Italy
| | - Romina Fiorotto
- Section of Digestive Diseases, Liver Center, Yale University, New Haven, Connecticut
| | - Ambra Villani
- Section of Digestive Diseases, Liver Center, Yale University, New Haven, Connecticut
| | - Mariangela Amenduni
- Section of Digestive Diseases, Liver Center, Yale University, New Haven, Connecticut
| | - Carlo Spirli
- Section of Digestive Diseases, Liver Center, Yale University, New Haven, Connecticut
| | - Mario Strazzabosco
- Section of Digestive Diseases, Liver Center, Yale University, New Haven, Connecticut,Department of Surgery and Translational Medicine, University of Milano-Bicocca, Milan, Italy
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Huqi San-Evoked Rat Colonic Anion Secretion through Increasing CFTR Expression. EVIDENCE-BASED COMPLEMENTARY AND ALTERNATIVE MEDICINE 2015; 2015:301640. [PMID: 26290673 PMCID: PMC4531196 DOI: 10.1155/2015/301640] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/13/2014] [Revised: 10/06/2014] [Accepted: 10/12/2014] [Indexed: 02/07/2023]
Abstract
Huqi San (HQS) is a Chinese herbal preparation of eight medicinal herbs that promote diuresis, detoxification, blood circulation, and cholestasis. Defects in transporter expression and function can cause cholestasis and jaundice. However, the mechanism of the cholestasis underlying HQS effects, especially on the gastrointestinal tract ion secretion, has not been elucidated. Real-time RT-PCR and Western blotting were used to study the expression and localization of cystic fibrosis transmembrane conductance regulator (CFTR) and α-ENaC in rat alimentary tract, and then the effect of HQS on the ion transport in rat distal colon mucosa was investigated using the short-circuit current (ISC) technique. The results showed that pretreatment with HQS significantly enhanced mRNA transcripts and protein content of CFTR in liver and distal colon but not α-ENaC in alimentary organs. HQS increases ISC and decreases the transepithelial resistance. Pretreatment with epithelial Na+ channel blocker did not affect the ISC responses elicited by HQS, but removal of extracellular Cl− or pretreatment with Cl− channel or Na+-K+-2Cl− cotransporter blocker inhibited HQS-elicited ISC responses. These findings demonstrated that HQS, RA, and RP can stimulate Cl− secretion in the distal colon by increasing the mRNA transcripts and protein content of CFTR in liver and distal colon.
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28
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Guerra MT, Nathanson MH. Calcium signaling and secretion in cholangiocytes. Pancreatology 2015; 15:S44-8. [PMID: 26100660 PMCID: PMC4603373 DOI: 10.1016/j.pan.2015.05.477] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/05/2014] [Revised: 05/08/2015] [Accepted: 05/27/2015] [Indexed: 12/11/2022]
Abstract
Alcoholic hepatitis affects up to one-third of individuals who abuse alcohol and can be associated with high mortality. Although this disorder is characterized by hepatocellular damage, steatosis and neutrophil infiltration, recent evidence suggests that cholestasis or impaired bile secretion may be a frequent occurrence as well. Bile secretion results from the concerted activity of hepatocytes and cholangiocytes, the epithelial cells that line the bile ducts. Hepatocytes secrete bile acids and conjugated products into the bile canaliculi, which then are modified by cholangiocytes through secretion of bicarbonate and water to give rise to the final secreted bile. Here the molecular mechanisms regulating bile secretion in cholangiocytes are reviewed. Moreover, we discuss how the expression of intracellular Ca(2+) channels might be regulated in cholangiocytes, plus evidence that components of the Ca(2+) signaling machinery are altered in a range of cholestatic diseases of the bile ducts.
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Affiliation(s)
- Mateus T. Guerra
- Section of Digestive Diseases, Department of Internal Medicine, Yale University School of Medicine
| | - Michael H. Nathanson
- Section of Digestive Diseases, Department of Internal Medicine, Yale University School of Medicine,Correspondence to: Michael H. Nathanson, 300 Cedar Street, TAC S241D, New Haven, CT. USA. 06520-8019, Phone: +1 203 785 7312, Fax: +1 203 785 7273,
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Kowal JM, Haanes KA, Christensen NM, Novak I. Bile acid effects are mediated by ATP release and purinergic signalling in exocrine pancreatic cells. Cell Commun Signal 2015; 13:28. [PMID: 26050734 PMCID: PMC4459444 DOI: 10.1186/s12964-015-0107-9] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2015] [Accepted: 05/26/2015] [Indexed: 02/06/2023] Open
Abstract
Background In many cells, bile acids (BAs) have a multitude of effects, some of which may be mediated by specific receptors such the TGR5 or FXR receptors. In pancreas systemic BAs, as well as intra-ductal BAs from bile reflux, can affect pancreatic secretion. Extracellular ATP and purinergic signalling are other important regulators of similar secretory mechanisms in pancreas. The aim of our study was to elucidate whether there is interplay between ATP and BA signalling. Results Here we show that CDCA (chenodeoxycholic acid) caused fast and concentration-dependent ATP release from acini (AR42J) and duct cells (Capan-1). Taurine and glycine conjugated forms of CDCA had smaller effects on ATP release in Capan-1 cells. In duct monolayers, CDCA stimulated ATP release mainly from the luminal membrane; the releasing mechanisms involved both vesicular and non-vesicular secretion pathways. Duct cells were not depleted of intracellular ATP with CDCA, but acinar cells lost some ATP, as detected by several methods including ATP sensor AT1.03YEMK. In duct cells, CDCA caused reversible increase in the intracellular Ca2+ concentration [Ca2 +]i, which could be significantly inhibited by antagonists of purinergic receptors. The TGR5 receptor, expressed on the luminal side of pancreatic ducts, was not involved in ATP release and Ca2+ signals, but could stimulate Na+/Ca2+ exchange in some conditions. Conclusions CDCA evokes significant ATP release that can stimulate purinergic receptors, which in turn increase [Ca2+]i. The TGR5 receptor is not involved in these processes but can play a protective role at high intracellular Ca2+ conditions. We propose that purinergic signalling could be taken into consideration in other cells/organs, and thereby potentially explain some of the multifaceted effects of BAs. Electronic supplementary material The online version of this article (doi:10.1186/s12964-015-0107-9) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Justyna M Kowal
- Department of Biology, Section for Cell Biology and Physiology, August Krogh Building, University of Copenhagen, Universitetsparken 13, DK-2100, Copenhagen, Denmark.
| | - Kristian A Haanes
- Department of Biology, Section for Cell Biology and Physiology, August Krogh Building, University of Copenhagen, Universitetsparken 13, DK-2100, Copenhagen, Denmark. .,Present address: Department of Clinical Experimental Research, Glostrup Research Institute, Copenhagen University Hospital, Glostrup, Denmark.
| | - Nynne M Christensen
- Department of Biology, Section for Cell Biology and Physiology, August Krogh Building, University of Copenhagen, Universitetsparken 13, DK-2100, Copenhagen, Denmark.
| | - Ivana Novak
- Department of Biology, Section for Cell Biology and Physiology, August Krogh Building, University of Copenhagen, Universitetsparken 13, DK-2100, Copenhagen, Denmark.
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30
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Poupon R. Liver alkaline phosphatase: a missing link between choleresis and biliary inflammation. Hepatology 2015; 61:2080-90. [PMID: 25603770 DOI: 10.1002/hep.27715] [Citation(s) in RCA: 69] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/25/2014] [Accepted: 01/16/2015] [Indexed: 02/06/2023]
Abstract
Several lines of evidence show that serum alkaline phosphatase (AP) is not only a signpost of cholestasis but also a surrogate marker of the severity of primary biliary cirrhosis and primary sclerosing cholangitis. In the present opinion article, we review and discuss the putative role of liver AP in health and in cholestatic diseases. In inflammatory cholestatic conditions, loss of activity of liver AP (resulting from its relocation from canaliculi and the acidic milieu) might promote hyper-adenosine triphosphate-bilia, lipopolysaccharide overload, and subsequent exacerbation and perpetuation of inflammation. Drugs that can restore the polarity of hepatocytes and canalicular export of bile acids or act as bile alkalinity modifiers are predicted to exert anti-inflammatory effects and to benefit both primary biliary cirrhosis and primary sclerosing cholangitis. Oral administration of intestinal AP could be a valid therapeutic intervention that deserves further study under experimental conditions as well as in human diseases. Overall, the key role of the liver microenvironment that might shape the different facets of the inflammatory processes in fibrosing cholangiopathies is highlighted.
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Affiliation(s)
- Raoul Poupon
- UPMC University of Paris 06, INSERM, UMR_S 938, Centre de Recherche Saint-Antoine, Paris, France.,AP-HP, Hôpital Saint-Antoine, Service d'Hépatologie, Paris, France
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31
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Fouassier L, Fiorotto R. Ezrin finds its groove in cholangiocytes. Hepatology 2015; 61:1467-70. [PMID: 25545157 PMCID: PMC4406785 DOI: 10.1002/hep.27675] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/20/2014] [Accepted: 12/18/2014] [Indexed: 12/07/2022]
Affiliation(s)
- Laura Fouassier
- INSERM, UMR_S 938, Centre de Recherche Saint-Antoine, F-75012, Paris, France,Sorbonne Universités, UPMC Univ Paris 06, UMR_S 938, Centre de Recherche Saint-Antoine F-75012, Paris, France
| | - Romina Fiorotto
- Section of Digestive Diseases, Liver Center, Yale University School of Medicine, Cedar Street 333, New Haven, CT 06520, USA
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Saiman Y, Sugiyama T, Simchoni N, Spirli C, Bansal MB. Biliary Epithelial Cells Are Not the Predominant Source of Hepatic CXCL12. THE AMERICAN JOURNAL OF PATHOLOGY 2015; 185:1859-66. [PMID: 25934614 DOI: 10.1016/j.ajpath.2015.03.006] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/12/2014] [Revised: 03/09/2015] [Accepted: 03/17/2015] [Indexed: 11/29/2022]
Abstract
Hepatic expression levels of CXCL12, a chemokine important in inflammatory and stem cell recruitment, and its receptor, C-X-C chemokine receptor 4, are increased during all forms of liver injury. CXCL12 is expressed by both parenchymal and nonparenchymal hepatic cells, and on the basis of immunohistochemistry, biliary epithelial cells (BECs) are thought to be a predominant source of hepatic CXCL12, thereby promoting periportal recruitment of C-X-C chemokine receptor 4-expressing lymphocytes. Our study aims to show that BECs may, in fact, not be the predominant source of hepatic CXCL12. We measured CXCL12 secretion and expression from human and murine BECs using enzyme-linked immunosorbent assay and Western blot analysis from cell culture supernatants and whole cell lysates, respectively, whereas CXCL12 expression in murine livers was analyzed in a Cxcl12-Gfp reporter mouse. Cell culture supernatants and whole cell lysates from BECs failed to demonstrate their expression of CXCL12. Furthermore, we confirmed these results with a Cxcl12-Gfp reporter mouse in which green fluorescent protein expression is notably absent from BECs. Interestingly, on the basis of green fluorescent protein expression, we demonstrate a population of CXCL12-expressing cells within the portal tract that are distinct, yet intimately associated with BECs. These findings indicate that BECs are not a predominant source of CXCL12.
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Affiliation(s)
- Yedidya Saiman
- Division of Liver Diseases, Department of Medicine, Icahn School of Medicine at Mount Sinai, New York, New York
| | - Tatsuki Sugiyama
- Department of Immunobiology and Hematology, Institute for Frontier Medical Sciences, Kyoto University, Kyoto, Japan
| | - Noa Simchoni
- Division of Clinical Immunology, Department of Medicine, Icahn School of Medicine at Mount Sinai, New York, New York
| | - Carlo Spirli
- Liver Center and Digestive Diseases Section, Department of Internal Medicine, Yale School of Medicine, New Haven, Connecticut
| | - Meena B Bansal
- Division of Liver Diseases, Department of Medicine, Icahn School of Medicine at Mount Sinai, New York, New York.
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Abdelkader NF, Safar MM, Salem HA. Ursodeoxycholic Acid Ameliorates Apoptotic Cascade in the Rotenone Model of Parkinson's Disease: Modulation of Mitochondrial Perturbations. Mol Neurobiol 2014; 53:810-817. [PMID: 25502462 DOI: 10.1007/s12035-014-9043-8] [Citation(s) in RCA: 83] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2014] [Accepted: 12/02/2014] [Indexed: 12/14/2022]
Abstract
The recent emergence of ursodeoxycholic acid (UDCA) as a contender in modifying neurotoxicity in human dopaminergic cells as well as its recognized anti-apoptotic and anti-inflammatory potentials in various hepatic pathologies raised impetus in investigating its anti-parkinsonian effect in rat rotenone model. UDCA prominently improved motor performance in the open field test and halted the decline in the striatal dopamine content. Meanwhile, it improved mitochondrial function as verified by elevation of ATP associated with preservation of mitochondrial integrity as portrayed in the electron microscope examination. In addition, through its anti-inflammatory potential, UDCA reduced the rotenone-induced nuclear factor-κB expression and tumor necrosis factor alpha level. Furthermore, UDCA amended alterations in Bax and Bcl-2 and reduced the activities of caspase-8, caspase-9, and caspase-3, indicating that it suppressed rotenone-induced apoptosis via modulating both intrinsic and extrinsic pathways. In conclusion, UDCA can be introduced as a novel approach for the management of Parkinson's disease via anti-apoptotic and anti-inflammatory mechanisms. These effects are probably linked to dopamine synthesis and mitochondrial regulation.
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Affiliation(s)
- Noha F Abdelkader
- Department of Pharmacology and Toxicology, Faculty of Pharmacy, Cairo University, Cairo, Egypt
| | - Marwa M Safar
- Department of Pharmacology and Toxicology, Faculty of Pharmacy, Cairo University, Cairo, Egypt.
| | - Hesham A Salem
- Department of Pharmacology and Toxicology, Faculty of Pharmacy, Cairo University, Cairo, Egypt
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Hendrick SM, Mroz MS, Greene CM, Keely SJ, Harvey BJ. Bile acids stimulate chloride secretion through CFTR and calcium-activated Cl- channels in Calu-3 airway epithelial cells. Am J Physiol Lung Cell Mol Physiol 2014; 307:L407-18. [PMID: 24993131 DOI: 10.1152/ajplung.00352.2013] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023] Open
Abstract
Bile acids resulting from the aspiration of gastroesophageal refluxate are often present in the lower airways of people with cystic fibrosis and other respiratory distress diseases. Surprisingly, there is little or no information on the modulation of airway epithelial ion transport by bile acids. The secretory effect of a variety of conjugated and unconjugated secondary bile acids was investigated in Calu-3 airway epithelial cells grown under an air-liquid interface and mounted in Ussing chambers. Electrogenic transepithelial ion transport was measured as short-circuit current (Isc). The taurine-conjugated secondary bile acid, taurodeoxycholic acid (TDCA), was found to be the most potent modulator of basal ion transport. Acute treatment (5 min) of Calu-3 cells with TDCA (25 μM) on the basolateral side caused a stimulation of Isc, and removal of extracellular Cl(-) abolished this response. TDCA produced an increase in the cystic fibrosis transmembrane conductance regulator (CFTR)-dependent current that was abolished by pretreatment with the CFTR inhibitor CFTRinh172. TDCA treatment also increased Cl(-) secretion through calcium-activated chloride (CaCC) channels and increased the Na(+)/K(+) pump current. Acute treatment with TDCA resulted in a rapid cellular influx of Ca(2+) and increased cAMP levels in Calu-3 cells. Bile acid receptor-selective activation with INT-777 revealed TGR5 localized at the basolateral membrane as the receptor involved in TDCA-induced Cl(-) secretion. In summary, we demonstrate for the first time that low concentrations of bile acids can modulate Cl(-) secretion in airway epithelial cells, and this effect is dependent on both the duration and sidedness of exposure to the bile acid.
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Affiliation(s)
| | | | - Catherine M Greene
- Respiratory Medicine, Royal College of Surgeons in Ireland, Education and Research Centre, Beaumont Hospital, Dublin, Ireland
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35
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Liver disease in cystic fibrosis. GASTROENTEROLOGY REVIEW 2014; 9:136-41. [PMID: 25097709 PMCID: PMC4110359 DOI: 10.5114/pg.2014.43574] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Received: 10/26/2011] [Revised: 09/21/2012] [Accepted: 11/25/2012] [Indexed: 12/14/2022]
Abstract
Cystic fibrosis-associated liver disease (CFLD) affects ca. 30% of patients. The CFLD is now considered the third cause of death, after lung disease and transplantation complications, in CF patients. Diagnostics, clinical assessment and treatment of CFLD have become a real challenge since a striking increase of life expectancy in CF patients has recently been observed. There is no elaborated "gold standard" in the diagnostic process of CFLD; clinical evaluation, laboratory tests, ultrasonography and liver biopsy are used. Clinical forms of CFLD are elevation of serum liver enzymes, hepatic steatosis, focal biliary cirrhosis, multilobular biliary cirrhosis, neonatal cholestasis, cholelithiasis, cholecystitis and micro-gallbladder. In children, CFLD symptoms mostly occur in puberty. Clinical symptoms appear late, when damage of the hepatobiliary system is already advanced. The CFLD is more common in patients with severe mutations of CFTR gene, in whom a complete loss of CFTR protein function is observed. CFLD, together with exocrine pancreatic insufficiency and meconium ileus, is considered a component of the severe CF phenotype. Treatment of CFLD should be complex and conducted by a multispecialist team (gastroenterologist, hepatologist, dietician, radiologist, surgeon). The main aim of the treatment is to prevent liver damage and complications associated with portal hypertension and liver cirrhosis. Ursodeoxycholic acid is used in the treatment of CFLD. There is no treatment of proven long-term efficacy in CFLD. Liver transplantation is a treatment of choice in end-stage liver disease.
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Kagawa T, Orii R, Hirose S, Arase Y, Shiraishi K, Mizutani A, Tsukamoto H, Mine T. Ursodeoxycholic acid stabilizes the bile salt export pump in the apical membrane in MDCK II cells. J Gastroenterol 2014; 49:890-9. [PMID: 23722250 DOI: 10.1007/s00535-013-0833-y] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/09/2013] [Accepted: 05/03/2013] [Indexed: 02/04/2023]
Abstract
BACKGROUND Ursodeoxycholic acid (UDCA) partly exerts choleretic effects by modifying the function of the bile salt export pump (Bsep, ABCB11). UDCA induces insertion of Bsep into the canalicular membrane of hepatocytes; however, underlying mechanisms remain unknown. We aimed to elucidate molecular mechanisms behind UDCA-induced Bsep activation. METHODS We established MDCK II cells stably expressing both Bsep and Na(+)-taurocholate cotransporting polypeptide, and investigated the effect of UDCA on activity and protein expression of Bsep using these cells. We performed inhibitor study to know the molecules involved in UDCA-induced Bsep activation, and also tested the influence of UDCA on Bsep having a disease-associated mutation. RESULTS UDCA activated Bsep in a dose-dependent manner. UDCA did not affect Bsep protein expression in whole cell lysates but increased its apical surface expression by extending the half-life from 2.4 to 5.0 h. This effect was specific to Bsep because UDCA did not affect other apical and basolateral proteins, and was independent of protein kinase A, adenylate cyclase, p38(MAPK), phosphatidylinositide 3-kinase, Ca(2+), and microtubules. NorUDCA activated Bsep similar to UDCA; however, cholic acid, taurocholic acid, and tauroUDCA had no effect. UDCA significantly increased the activity of Bsep with a benign recurrent intrahepatic cholestasis 2 mutation (A570T) but did not affect Bsep with a progressive familial intrahepatic cholestasis 2 mutation (G982R or D482G). CONCLUSIONS We demonstrated that UDCA stabilizes Bsep protein in the apical membrane and increases its activity in MDCK II cells, presumably by retarding the endocytotic process.
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Affiliation(s)
- Tatehiro Kagawa
- Division of Gastroenterology, Department of Internal Medicine, Tokai University School of Medicine, Shimokasuya 143, Isehara, Kanagawa, 259-1193, Japan,
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Burnstock G. Purinergic signalling in the gastrointestinal tract and related organs in health and disease. Purinergic Signal 2014; 10:3-50. [PMID: 24307520 PMCID: PMC3944042 DOI: 10.1007/s11302-013-9397-9] [Citation(s) in RCA: 84] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2013] [Accepted: 10/24/2013] [Indexed: 01/04/2023] Open
Abstract
Purinergic signalling plays major roles in the physiology and pathophysiology of digestive organs. Adenosine 5'-triphosphate (ATP), together with nitric oxide and vasoactive intestinal peptide, is a cotransmitter in non-adrenergic, non-cholinergic inhibitory neuromuscular transmission. P2X and P2Y receptors are widely expressed in myenteric and submucous enteric plexuses and participate in sympathetic transmission and neuromodulation involved in enteric reflex activities, as well as influencing gastric and intestinal epithelial secretion and vascular activities. Involvement of purinergic signalling has been identified in a variety of diseases, including inflammatory bowel disease, ischaemia, diabetes and cancer. Purinergic mechanosensory transduction forms the basis of enteric nociception, where ATP released from mucosal epithelial cells by distension activates nociceptive subepithelial primary afferent sensory fibres expressing P2X3 receptors to send messages to the pain centres in the central nervous system via interneurons in the spinal cord. Purinergic signalling is also involved in salivary gland and bile duct secretion.
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Affiliation(s)
- Geoffrey Burnstock
- Autonomic Neuroscience Centre, University College Medical School, Rowland Hill Street, London, NW3 2PF, UK,
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Amaya MJ, Nathanson MH. Calcium signaling and the secretory activity of bile duct epithelia. Cell Calcium 2014; 55:317-24. [PMID: 24612866 DOI: 10.1016/j.ceca.2014.02.003] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2013] [Revised: 02/03/2014] [Accepted: 02/04/2014] [Indexed: 12/20/2022]
Abstract
Cytosolic calcium (Cai(2+)) is a second messenger that is important for the regulation of secretion in many types of tissues. Bile duct epithelial cells, or cholangiocytes, are polarized epithelia that line the biliary tree in liver and are responsible for secretion of bicarbonate and other solutes into bile. Cai(2+) signaling plays an important role in the regulation of secretion by cholangiocytes, and this review discusses the machinery involved in the formation of Ca(2+) signals in cholangiocytes, along with the evidence that these signals regulate ductular secretion. Finally, this review discusses the evidence that impairments in cholangiocyte Ca(2+) signaling play a primary role in the pathogenesis of cholestatic disorders, in which hepatic bile secretion is impaired.
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Affiliation(s)
- Maria Jimena Amaya
- Section of Digestive Diseases, Department of Internal Medicine, Yale University, 333 Cedar Street, PO Box 208019, New Haven, CT 06520-8019, USA
| | - Michael H Nathanson
- Section of Digestive Diseases, Department of Internal Medicine, Yale University, 333 Cedar Street, PO Box 208019, New Haven, CT 06520-8019, USA.
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Sabbatini ME, Gorelick F, Glaser S. Adenylyl cyclases in the digestive system. Cell Signal 2014; 26:1173-81. [PMID: 24521753 DOI: 10.1016/j.cellsig.2014.01.033] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2014] [Accepted: 01/31/2014] [Indexed: 02/08/2023]
Abstract
Adenylyl cyclases (ACs) are a group of widely distributed enzymes whose functions are very diverse. There are nine known transmembrane AC isoforms activated by Gαs. Each has its own pattern of expression in the digestive system and differential regulation of function by Ca(2+) and other intracellular signals. In addition to the transmembrane isoforms, one AC is soluble and exhibits distinct regulation. In this review, the basic structure, regulation and physiological roles of ACs in the digestive system are discussed.
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Affiliation(s)
| | - Fred Gorelick
- Department of Cell Biology and Medicine, Yale University, United States; VA CT, United States
| | - Shannon Glaser
- Department of Internal Medicine, Scott & White-Digestive Disease Research Center, Texas A&M Health Science Center, Central Texas Veterans Health Care System, United States
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Concepcion AR, Lopez M, Ardura-Fabregat A, Medina JF. Role of AE2 for pHi regulation in biliary epithelial cells. Front Physiol 2014; 4:413. [PMID: 24478713 PMCID: PMC3894451 DOI: 10.3389/fphys.2013.00413] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2013] [Accepted: 12/27/2013] [Indexed: 12/31/2022] Open
Abstract
The Cl−/HCO−3anion exchanger 2 (AE2) is known to be involved in intracellular pH (pHi) regulation and transepithelial acid-base transport. Early studies showed that AE2 gene expression is reduced in liver biopsies and blood mononuclear cells from patients with primary biliary cirrhosis (PBC), a disease characterized by chronic non-suppurative cholangitis associated with antimitochondrial antibodies (AMA) and other autoimmune phenomena. Microfluorimetric analysis of the Cl−/HCO−3 anion exchange (AE) in isolated cholangiocytes showed that the cAMP-stimulated AE activity is diminished in PBC compared to both healthy and diseased controls. More recently, it was found that miR-506 is upregulated in cholangiocytes of PBC patients and that AE2 may be a target of miR-506. Additional evidence for a pathogenic role of AE2 dysregulation in PBC was obtained with Ae2−/−a,b mice, which develop biochemical, histological, and immunologic alterations that resemble PBC (including development of serum AMA). Analysis of HCO−3 transport systems and pHi regulation in cholangiocytes from normal and Ae2−/−a,b mice confirmed that AE2 is the transporter responsible for the Cl−/HCO−3exchange in these cells. On the other hand, both Ae2+/+a,b and Ae2−/−a,b mouse cholangiocytes exhibited a Cl−-independent bicarbonate transport system, essentially a Na+-bicarbonate cotransport (NBC) system, which could contribute to pHi regulation in the absence of AE2.
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Affiliation(s)
- Axel R Concepcion
- Division of Gene Therapy and Hepatology, Center for Applied Medical Research (CIMA), School of Medicine, University of Navarra, and Ciberehd Pamplona, Spain
| | - María Lopez
- Division of Gene Therapy and Hepatology, Center for Applied Medical Research (CIMA), School of Medicine, University of Navarra, and Ciberehd Pamplona, Spain
| | - Alberto Ardura-Fabregat
- Division of Gene Therapy and Hepatology, Center for Applied Medical Research (CIMA), School of Medicine, University of Navarra, and Ciberehd Pamplona, Spain
| | - Juan F Medina
- Division of Gene Therapy and Hepatology, Center for Applied Medical Research (CIMA), School of Medicine, University of Navarra, and Ciberehd Pamplona, Spain
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Abstract
Intracellular free Ca(2+) ([Ca(2+)]i) is a highly versatile second messenger that regulates a wide range of functions in every type of cell and tissue. To achieve this versatility, the Ca(2+) signaling system operates in a variety of ways to regulate cellular processes that function over a wide dynamic range. This is particularly well exemplified for Ca(2+) signals in the liver, which modulate diverse and specialized functions such as bile secretion, glucose metabolism, cell proliferation, and apoptosis. These Ca(2+) signals are organized to control distinct cellular processes through tight spatial and temporal coordination of [Ca(2+)]i signals, both within and between cells. This article will review the machinery responsible for the formation of Ca(2+) signals in the liver, the types of subcellular, cellular, and intercellular signals that occur, the physiological role of Ca(2+) signaling in the liver, and the role of Ca(2+) signaling in liver disease.
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Affiliation(s)
- Maria Jimena Amaya
- Section of Digestive Diseases, Department of Internal Medicine, Yale University School of Medicine, New Haven, Connecticut, USA
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Tabibian JH, Masyuk AI, Masyuk TV, O'Hara SP, LaRusso NF. Physiology of cholangiocytes. Compr Physiol 2013; 3:541-65. [PMID: 23720296 DOI: 10.1002/cphy.c120019] [Citation(s) in RCA: 157] [Impact Index Per Article: 14.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Cholangiocytes are epithelial cells that line the intra- and extrahepatic ducts of the biliary tree. The main physiologic function of cholangiocytes is modification of hepatocyte-derived bile, an intricate process regulated by hormones, peptides, nucleotides, neurotransmitters, and other molecules through intracellular signaling pathways and cascades. The mechanisms and regulation of bile modification are reviewed herein.
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Wiemuth D, Sahin H, Lefèvre CMT, Wasmuth HE, Gründer S. Strong activation of bile acid-sensitive ion channel (BASIC) by ursodeoxycholic acid. Channels (Austin) 2012; 7:38-42. [PMID: 23064163 PMCID: PMC3589280 DOI: 10.4161/chan.22406] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023] Open
Abstract
Bile acid-sensitive ion channel (BASIC) is a member of the DEG/ENaC gene family of unknown function. Rat BASIC (rBASIC) is inactive at rest. We have recently shown that cholangiocytes, the epithelial cells lining the bile ducts, are the main site of BASIC expression in the liver and identified bile acids, in particular hyo- and chenodeoxycholic acid, as agonists of rBASIC. Moreover, it seems that extracellular divalent cations stabilize the resting state of rBASIC, because removal of extracellular divalent cations opens the channel. In this addendum, we demonstrate that removal of extracellular divalent cations potentiates the activation of rBASIC by bile acids, suggesting an allosteric mechanism. Furthermore, we show that rBASIC is strongly activated by the anticholestatic bile acid ursodeoxycholic acid (UDCA), suggesting that BASIC might mediate part of the therapeutic effects of UDCA.
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Affiliation(s)
- Dominik Wiemuth
- Department of Physiology, RWTH Aachen University, Aachen, Germany.
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Urosdeoxycholic acid in primary sclerosing cholangitis: a meta-analysis and systematic review. Arab J Gastroenterol 2012; 13:103-10. [PMID: 23122450 DOI: 10.1016/j.ajg.2012.06.011] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/01/2011] [Revised: 02/23/2012] [Accepted: 06/10/2012] [Indexed: 01/06/2023]
Abstract
BACKGROUND AND STUDY AIMS Primary sclerosing cholangitis (PSC) is a chronic cholestatic liver disease with no proven effective medical therapy. Ursodeoxycholic acid (UDCA) was proposed as a potential treatment for this disorder. However, several randomised controlled trials reported conflicting results regarding the usefulness of UDCA. The aim of this meta-analysis and systematic review is to investigate the efficacy of UDCA in PSC. PATIENTS AND METHODS Literature review was performed to include randomised controlled trials and non-randomised studies comparing UDCA to a placebo in PSC. The included controlled trials were assigned a quality score. Random effects model was used. Outcomes were measured with Weight Mean Difference, Risk Ratio or Risk Difference. Heterogeneity was measured by I(2) measure of inconsistency. RESULTS Seven RCTs satisfied the inclusion criteria with a total number of 553 patients. Low dose UDCA was used in 4 studies, high dose UDCA (17-30mg/kg) was used in three studies. UDCA did not decrease the risk of mortality compared to placebo (RR=1.04, 95% CI 0.46-2.35) or the need for liver transplant (RR=1.22, 95% CI 0.7-2.12). UDCA also had no effect on the clinical symptoms. Liver Function Tests (LFTs) were significantly improved in the UDCA treated patients. UDCA did not decrease the incidence of cholangiocarcinoma. CONCLUSION UDCA had no beneficial effect on the patients' survival, liver histology, prevention of cholangiocarcinoma, or improvement of clinical symptoms. High dose UDCA was associated with increased mortality in one of the large randomised trial included in this analysis.
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Maillette de Buy Wenniger LJ, Oude Elferink RP, Beuers U. Molecular targets for the treatment of fibrosing cholangiopathies. Clin Pharmacol Ther 2012; 92:381-7. [PMID: 22850600 DOI: 10.1038/clpt.2012.111] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Emerging pathophysiologic insights are leading to novel approaches to treating fibrosing cholangiopathies. The current treatment, using ursodeoxycholic acid (UDCA), may slow the progression of some chronic cholangiopathies but cannot heal them. Apart from immunosuppressive interventions aimed at minimizing immune-mediated damage, the use of specific modifiers of hepatobiliary secretory and cytoprotective mechanisms may eventually give rise to a new class of disease-modifying anti-cholangiofibrotic drugs.
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Affiliation(s)
- L J Maillette de Buy Wenniger
- Department of Gastroenterology and Hepatology, Tytgat Institute for Liver and Intestinal Research, Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands
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Bodewes FAJA, Wouthuyzen-Bakker M, Bijvelds MJ, Havinga R, de Jonge HR, Verkade HJ. Ursodeoxycholate modulates bile flow and bile salt pool independently from the cystic fibrosis transmembrane regulator (Cftr) in mice. Am J Physiol Gastrointest Liver Physiol 2012; 302:G1035-42. [PMID: 22301109 DOI: 10.1152/ajpgi.00258.2011] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
Cystic fibrosis liver disease (CFLD) is treated with ursodeoxycholate (UDCA). Our aim was to evaluate, in cystic fibrosis transmembrane regulator knockout (Cftr(-/-)) mice and wild-type controls, whether the supposed therapeutic action of UDCA is mediated via choleretic activity or effects on bile salt metabolism. Cftr(-/-) mice and controls, under general anesthesia, were intravenously infused with tauroursodeoxycholate (TUDCA) in increasing dosage or were fed either standard or UDCA-enriched chow (0.5% wt/wt) for 3 wk. Bile flow and bile composition were characterized. In chow-fed mice, we analyzed bile salt synthesis and pool size of cholate (CA). In both Cftr(-/-) and controls intravenous TUDCA stimulated bile flow by ∼250% and dietary UDCA by ∼500%, compared with untreated animals (P < 0.05). In non-UDCA-treated Cftr(-/-) mice, the proportion of CA in bile was higher compared with that in controls (61 ± 4 vs. 46 ± 4%; P < 0.05), accompanied by an increased CA synthesis [16 ± 1 vs. 10 ± 2 μmol·h(-1)·100 g body wt (BW)(-1); P < 0.05] and CA pool size (28 ± 3 vs. 19 ± 1 μmol/100 g BW; P < 0.05). In both Cftr(-/-) and controls, UDCA treatment drastically reduced the proportion of CA in bile below 5% and diminished CA synthesis (2.3 ± 0.3 vs. 2.2 ± 0.4 μmol·day(-1)·100 g BW(-1); nonsignificant) and CA pool size (3.6 ± 0.6 vs. 1.5 ± 0.3 μmol/100 g BW; P < 0.05). Acute TUDCA infusion and chronic UDCA treatment both stimulate bile flow in cystic fibrosis conditions independently from Cftr function. Chronic UDCA treatment reduces the hydrophobicity of the bile salt pool in Cftr(-/-) mice. These results support a potential beneficial effect of UDCA on bile flow and bile salt metabolism in cystic fibrosis conditions.
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Affiliation(s)
- Frank A J A Bodewes
- Department of Pediatrics, University of Groningen, Beatrix Children's Hospital, University Medical Center, Groningen, The Netherlands.
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Fausther M, Lecka J, Soliman E, Kauffenstein G, Pelletier J, Sheung N, Dranoff JA, Sévigny J. Coexpression of ecto-5'-nucleotidase/CD73 with specific NTPDases differentially regulates adenosine formation in the rat liver. Am J Physiol Gastrointest Liver Physiol 2012; 302:G447-59. [PMID: 22135310 PMCID: PMC3287391 DOI: 10.1152/ajpgi.00165.2011] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
Ectonucleotidases modulate purinergic signaling by hydrolyzing ATP to adenosine. Here we characterized the impact of the cellular distribution of hepatic ectonucleotidases, namely nucleoside triphosphate diphosphohydrolase (NTPDase)1/CD39, NTPDase2/CD39L1, NTPDase8, and ecto-5'-nucleotidase/CD73, and of their specific biochemical properties, on the levels of P1 and P2 receptor agonists, with an emphasis on adenosine-producing CD73. Immunostaining and enzyme histochemistry showed that the distribution of CD73 (protein and AMPase activity) overlaps partially with those of NTPDase1, -2, and -8 (protein levels and ATPase and ADPase activities) in normal rat liver. CD73 is expressed in fibroblastic cells located underneath vascular endothelial cells and smooth muscle cells, which both express NTPDase1, in portal spaces in a distinct fibroblast population next to NTPDase2-positive portal fibroblasts, and in bile canaliculi, together with NTPDase8. In fibrotic rat livers, CD73 protein expression and activity are redistributed but still overlap with the NTPDases mentioned. The ability of the observed combinations of ectonucleotidases to generate adenosine over time was evaluated by reverse-phase HPLC with the recombinant rat enzymes at high "inflammatory" (500 μM) and low "physiological" (1 μM) ATP concentrations. Overall, ATP was rapidly converted to adenosine by the NTPDase1+CD73 combination, but not by the NTPDase2+CD73 combination. In the presence of NTPDase8 and CD73, ATP was sequentially dephosphorylated to the CD73 inhibitor ADP, and then to AMP, thus resulting in a delayed formation of adenosine. In conclusion, the specific cellular cocompartmentalization of CD73 with hepatic NTPDases is not redundant and may lead to the differential activation of P1 and P2 receptors, under normal and fibrotic conditions.
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Affiliation(s)
- Michel Fausther
- 1Centre de recherche en Rhumatologie et Immunologie, Centre Hospitalier Universitaire de Québec (pavillon CHUL), Québec and Département de microbiologie-infectiologie et d'immunologie, Faculté de médecine, Université Laval, Québec, QC, Canada; ,2Section of Digestive Diseases, Yale University School of Medicine, New Haven, Connecticut; and ,3Division of Gastroenterology and Hepatology, Department of Internal Medicine, College of Medicine, University of Arkansas for Medical Sciences, Little Rock, Arkansas
| | - Joanna Lecka
- 1Centre de recherche en Rhumatologie et Immunologie, Centre Hospitalier Universitaire de Québec (pavillon CHUL), Québec and Département de microbiologie-infectiologie et d'immunologie, Faculté de médecine, Université Laval, Québec, QC, Canada;
| | - Elwy Soliman
- 2Section of Digestive Diseases, Yale University School of Medicine, New Haven, Connecticut; and
| | - Gilles Kauffenstein
- 1Centre de recherche en Rhumatologie et Immunologie, Centre Hospitalier Universitaire de Québec (pavillon CHUL), Québec and Département de microbiologie-infectiologie et d'immunologie, Faculté de médecine, Université Laval, Québec, QC, Canada;
| | - Julie Pelletier
- 1Centre de recherche en Rhumatologie et Immunologie, Centre Hospitalier Universitaire de Québec (pavillon CHUL), Québec and Département de microbiologie-infectiologie et d'immunologie, Faculté de médecine, Université Laval, Québec, QC, Canada;
| | - Nina Sheung
- 2Section of Digestive Diseases, Yale University School of Medicine, New Haven, Connecticut; and
| | - Jonathan A. Dranoff
- 2Section of Digestive Diseases, Yale University School of Medicine, New Haven, Connecticut; and ,3Division of Gastroenterology and Hepatology, Department of Internal Medicine, College of Medicine, University of Arkansas for Medical Sciences, Little Rock, Arkansas
| | - Jean Sévigny
- 1Centre de recherche en Rhumatologie et Immunologie, Centre Hospitalier Universitaire de Québec (pavillon CHUL), Québec and Département de microbiologie-infectiologie et d'immunologie, Faculté de médecine, Université Laval, Québec, QC, Canada;
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Hohenester S, Wenniger LMDB, Paulusma CC, van Vliet SJ, Jefferson DM, Elferink RPO, Beuers U. A biliary HCO3- umbrella constitutes a protective mechanism against bile acid-induced injury in human cholangiocytes. Hepatology 2012; 55:173-83. [PMID: 21932391 DOI: 10.1002/hep.24691] [Citation(s) in RCA: 221] [Impact Index Per Article: 18.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
UNLABELLED Human cholangiocytes are continuously exposed to millimolar levels of hydrophobic bile salt monomers. We recently hypothesized that an apical biliary HCO3- umbrella might prevent the protonation of biliary glycine-conjugated bile salts and uncontrolled cell entry of the corresponding bile acids, and that defects in this biliary HCO3- umbrella might predispose to chronic cholangiopathies. Here, we tested in vitro whether human cholangiocyte integrity in the presence of millimolar bile salt monomers is dependent on (1) pH, (2) adequate expression of the key HCO3- exporter, anion exchanger 2 (AE2), and (3) an intact cholangiocyte glycocalyx. To address these questions, human immortalized cholangiocytes and cholangiocarcinoma cells were exposed to chenodeoxycholate and its glycine/taurine conjugates at different pH levels. Bile acid uptake was determined radiochemically. Cell viability and apoptosis were measured enzymatically. AE2 was knocked down by lentiviral short hairpin RNA. A cholangiocyte glycocalyx was identified by electron microscopy, was enzymatically desialylated, and sialylation was quantified by flow cytometry. We found that bile acid uptake and toxicity in human immortalized cholangiocytes and cholangiocarcinoma cell lines in vitro were pH and AE2 dependent, with the highest rates at low pH and when AE2 expression was defective. An apical glycocalyx was identified on cholangiocytes in vitro by electron microscopic techniques. Desialylation of this protective layer increased cholangiocellular vulnerability in a pH-dependent manner. CONCLUSION A biliary HCO3- umbrella protects human cholangiocytes against damage by bile acid monomers. An intact glycocalyx and adequate AE2 expression are crucial in this process. Defects of the biliary HCO3- umbrella may lead to the development of chronic cholangiopathies.
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Affiliation(s)
- Simon Hohenester
- Tytgat Institute for Liver and Intestinal Research, Department of Gastroenterology and Hepatology, Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands
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Úriz M, Sáez E, Prieto J, Medina JF, Banales JM. Ursodeoxycholic acid is conjugated with taurine to promote secretin-stimulated biliary hydrocholeresis in the normal rat. PLoS One 2011; 6:e28717. [PMID: 22194894 PMCID: PMC3237485 DOI: 10.1371/journal.pone.0028717] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2011] [Accepted: 11/14/2011] [Indexed: 12/15/2022] Open
Abstract
Background & Aims Secretin induces bicarbonate-rich hydrocholeresis in healthy individuals, but not in untreated patients with primary biliary cirrhosis (PBC). Ursodeoxycholic acid (UDCA) – the first choice treatment for PBC – restores the secretin response. Compared with humans, secretin has poor effect in experimental normal-rat models with biliary drainage, although it may elicit hydrocholeresis when the bile-acid pool is maintained. In view of the benefits of UDCA in PBC, we used normal-rat models to unravel the acute contribution of UDCA (and/or taurine-conjugated TUDCA) for eliciting the biliary secretin response. Methods Intravascular and/or intrabiliary administration of agonists and inhibitors was performed in normal rats with biliary monitoring. Secretin/bile-acid interplay was analyzed in 3D cultured rat cholangiocytes that formed expansive cystic structures with intralumenal hydroionic secretion. Results In vivo, secretin stimulates hydrocholeresis upon UDCA/TUDCA infusion, but does not modify the intrinsic hypercholeretic effect of dehydrocholic acid (DHCA). The former effect is dependent on microtubule polymerization, and involves PKCα, PI3K and MEK pathways, as shown by colchicine (i.p.) and retrograde biliary inhibitors. In vitro, while secretin alone accelerates the spontaneous expansion of 3D-cystic structures, this effect is enhanced in the presence of TUDCA, but not UDCA or DHCA. Experiments with inhibitors and Ca2+-chelator confirmed that the synergistic effect of secretin plus TUDCA involves microtubules, intracellular Ca2+, PKCα, PI3K, PKA and MEK pathways. Gene silencing also demonstrated the involvement of the bicarbonate extruder Ae2. Conclusions UDCA is conjugated in order to promote secretin-stimulated hydrocholeresis in rats through Ae2, microtubules, intracellular Ca2+, PKCα, PI3K, PKA, and MEK.
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Affiliation(s)
- Miriam Úriz
- Division of Gene Therapy and Hepatology, CIMA Clinic and School of Medicine, University of Navarra, Centro de Investigación Biomédica en Red en el Área temática de Enfermedades Hepáticas y Digestivas, Pamplona, Spain
| | - Elena Sáez
- Division of Gene Therapy and Hepatology, CIMA Clinic and School of Medicine, University of Navarra, Centro de Investigación Biomédica en Red en el Área temática de Enfermedades Hepáticas y Digestivas, Pamplona, Spain
| | - Jesús Prieto
- Division of Gene Therapy and Hepatology, CIMA Clinic and School of Medicine, University of Navarra, Centro de Investigación Biomédica en Red en el Área temática de Enfermedades Hepáticas y Digestivas, Pamplona, Spain
| | - Juan F. Medina
- Division of Gene Therapy and Hepatology, CIMA Clinic and School of Medicine, University of Navarra, Centro de Investigación Biomédica en Red en el Área temática de Enfermedades Hepáticas y Digestivas, Pamplona, Spain
- * E-mail: (JB); (JM)
| | - Jesús M. Banales
- Division of Gene Therapy and Hepatology, CIMA Clinic and School of Medicine, University of Navarra, Centro de Investigación Biomédica en Red en el Área temática de Enfermedades Hepáticas y Digestivas, Pamplona, Spain
- * E-mail: (JB); (JM)
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