1
|
Reshetnyak VI, Maev IV. New insights into the pathogenesis of primary biliary cholangitis asymptomatic stage. World J Gastroenterol 2023; 29:5292-5304. [PMID: 37899787 PMCID: PMC10600802 DOI: 10.3748/wjg.v29.i37.5292] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/19/2023] [Revised: 08/10/2023] [Accepted: 09/14/2023] [Indexed: 09/25/2023] Open
Abstract
Primary biliary cholangitis (PBC) is a chronic cholestatic progressive liver disease and one of the most important progressive cholangiopathies in adults. Damage to cholangiocytes triggers the development of intrahepatic cholestasis, which progresses to cirrhosis in the terminal stage of the disease. Accumulating data indicate that damage to biliary epithelial cells [(BECs), cholangiocytes] is most likely associated with the intracellular accumulation of bile acids, which have potent detergent properties and damaging effects on cell membranes. The mechanisms underlying uncontrolled bile acid intake into BECs in PBC are associated with pH change in the bile duct lumen, which is controlled by the bicarbonate (HCO3-) buffer system "biliary HCO3- umbrella". The impaired production and entry of HCO3- from BECs into the bile duct lumen is due to epigenetic changes in expression of the X-linked microRNA 506. Based on the growing body of knowledge on the molecular mechanisms of cholangiocyte damage in patients with PBC, we propose a hypothesis explaining the pathogenesis of the first morphologic (ductulopenia), immunologic (antimitochondrial autoantibodies) and clinical (weakness, malaise, rapid fatigue) signs of the disease in the asymptomatic stage. This review focuses on the consideration of these mechanisms.
Collapse
Affiliation(s)
- Vasiliy Ivanovich Reshetnyak
- Department of Propaedeutics of Internal Diseases and Gastroenterology, A.I. Yevdokimov Moscow State University of Medicine and Dentistry, Moscow 127473, Russia
| | - Igor Veniaminovich Maev
- Department of Propaedeutics of Internal Diseases and Gastroenterology, A.I. Yevdokimov Moscow State University of Medicine and Dentistry, Moscow 127473, Russia
| |
Collapse
|
2
|
Rodrigues MA, Gomes DA, Fiorotto R, Guerra MT, Weerachayaphorn J, Bo T, Sessa WC, Strazzabosco M, Nathanson MH. Molecular determinants of peri-apical targeting of inositol 1,4,5-trisphosphate receptor type 3 in cholangiocytes. Hepatol Commun 2022; 6:2748-2764. [PMID: 35852334 PMCID: PMC9512452 DOI: 10.1002/hep4.2042] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/03/2022] [Revised: 06/03/2022] [Accepted: 06/20/2022] [Indexed: 11/19/2022] Open
Abstract
Fluid and bicarbonate secretion is a principal function of cholangiocytes, and impaired secretion results in cholestasis. Cholangiocyte secretion depends on peri-apical expression of the type 3 inositol trisphosphate receptor (ITPR3), and loss of this intracellular Ca2+ release channel is a final common event in most cholangiopathies. Here we investigated the mechanism by which ITPR3 localizes to the apical region to regulate secretion. Isolated bile duct units, primary mouse cholangiocytes, and polarized Madin-Darby canine kidney (MDCK) cells were examined using a combination of biochemical and fluorescence microscopy techniques to investigate the mechanism of ITPR3 targeting to the apical region. Apical localization of ITPR3 depended on the presence of intact lipid rafts as well as interactions with both caveolin 1 (CAV1) and myosin heavy chain 9 (MYH9). Chemical disruption of lipid rafts or knockdown of CAV1 or MYH9 redistributed ITPR3 away from the apical region. MYH9 interacted with the five c-terminal amino acids of the ITPR3 peptide. Disruption of lipid rafts impaired Ca2+ signaling, and absence of CAV1 impaired both Ca2+ signaling and fluid secretion. Conclusion: A cooperative mechanism involving MYH9, CAV1, and apical lipid rafts localize ITPR3 to the apical region to regulate Ca2+ signaling and secretion in cholangiocytes.
Collapse
Affiliation(s)
- Michele A. Rodrigues
- Section of Digestive Diseases, Internal MedicineYale UniversityNew HavenConnecticutUSA
- Department of Biochemistry and ImmunologyFederal University of Minas Gerais (UFMG)Belo HorizonteMGBrazil
| | - Dawidson A. Gomes
- Section of Digestive Diseases, Internal MedicineYale UniversityNew HavenConnecticutUSA
- Department of Biochemistry and ImmunologyFederal University of Minas Gerais (UFMG)Belo HorizonteMGBrazil
| | - Romina Fiorotto
- Section of Digestive Diseases, Internal MedicineYale UniversityNew HavenConnecticutUSA
| | - Mateus T. Guerra
- Section of Digestive Diseases, Internal MedicineYale UniversityNew HavenConnecticutUSA
| | | | - Tao Bo
- Department of Pharmacology and Program in Vascular Cell Signaling and TherapeuticsYale University School of MedicineNew HavenConnecticutUSA
| | - William C. Sessa
- Department of Pharmacology and Program in Vascular Cell Signaling and TherapeuticsYale University School of MedicineNew HavenConnecticutUSA
| | - Mario Strazzabosco
- Section of Digestive Diseases, Internal MedicineYale UniversityNew HavenConnecticutUSA
| | - Michael H. Nathanson
- Section of Digestive Diseases, Internal MedicineYale UniversityNew HavenConnecticutUSA
| |
Collapse
|
3
|
Rodrigues MA, Gomes DA, Cosme AL, Sanches MD, Resende V, Cassali GD. Inositol 1,4,5-trisphosphate receptor type 3 (ITPR3) is overexpressed in cholangiocarcinoma and its expression correlates with S100 calcium-binding protein A4 (S100A4). Biomed Pharmacother 2022; 145:112403. [PMID: 34798470 PMCID: PMC8678364 DOI: 10.1016/j.biopha.2021.112403] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2021] [Revised: 10/31/2021] [Accepted: 11/03/2021] [Indexed: 01/03/2023] Open
Abstract
Cholangiocarcinoma (CCA) is the second most malignant neoplasm in the liver that arises from the biliary tree. CCA is associated with a poor prognosis, and the key players involved in its pathogenesis are still not well understood. Receptor tyrosine kinases (RTKs), such as epidermal growth factor receptor (EGFR), can mediate intracellular calcium (Ca2+) signaling pathways via inositol 1,4,5-trisphosphate (InsP3), activating inositol 1,4,5-trisphosphate receptors (ITPRs) and regulating tumor growth. ITPR isoform 3 (ITPR3) is the main intracellular Ca2+ release channel in cholangiocytes. The effects of intracellular Ca2+ are mediated by calcium-binding proteins such as Calmodulin and S100 calcium-binding protein A4 (S100A4). However, the clinicopathological and biological significance of EGFR, ITPR3 and S100A4 in CCA remains unclear. Thus, the present work investigates the immunoexpression of these three proteins in 59 CCAs from patients who underwent curative surgical treatment and correlates the data with clinicopathological features and survival. High ITPR3 expression was correlated with CA 19-9 levels, TNM stage and lymph node metastasis (N). Furthermore, ITPR3 expression was increased in distal CCA compared to control bile ducts and intrahepatic and perihilar CCAs. These observations were confirmed by proteomic analysis. ITPR3 and S100A4 clinical scores were significantly correlated. Furthermore, it was demonstrated that EGF induces calcium signaling in a cholangiocarcinoma cell line and ITPR3 colocalizes with nonmuscle myosin IIA (NMIIA). In summary, ITPR3 overexpression could contribute to CCA progression and it may represent a potential therapeutic target.
Collapse
Affiliation(s)
- Michele A. Rodrigues
- Department of General Pathology, Universidade Federal de Minas Gerais, Av. Antônio Carlos 6627, Belo Horizonte, Minas Gerais, CEP: 31270-901, Brazil
| | - Dawidson A. Gomes
- Department of Biochemistry and Immunology, Universidade Federal de Minas Gerais, Av. Antônio Carlos 6627, Belo Horizonte, Minas Gerais, CEP: 31270-901, Brazil
| | - Ana Luiza Cosme
- School of Medicine, Department of Surgery, Universidade Federal de Minas Gerais, Av. Prof. Alfredo Balena 190, Belo Horizonte, Minas Gerais, CEP: 30130-100, Brazil
| | - Marcelo Dias Sanches
- School of Medicine, Department of Surgery, Universidade Federal de Minas Gerais, Av. Prof. Alfredo Balena 190, Belo Horizonte, Minas Gerais, CEP: 30130-100, Brazil.,Hepatopancreatobiliary Division, Clinical Hospital, Universidade Federal de Minas Gerais, Av. Prof. Alfredo Balena 110, Belo Horizonte, Minas Gerais, CEP: 30130-100, Brazil
| | - Vivian Resende
- School of Medicine, Department of Surgery, Universidade Federal de Minas Gerais, Av. Prof. Alfredo Balena 190, Belo Horizonte, Minas Gerais, CEP: 30130-100, Brazil.,Hepatopancreatobiliary Division, Clinical Hospital, Universidade Federal de Minas Gerais, Av. Prof. Alfredo Balena 110, Belo Horizonte, Minas Gerais, CEP: 30130-100, Brazil
| | - Geovanni D. Cassali
- Department of General Pathology, Universidade Federal de Minas Gerais, Av. Antônio Carlos 6627, Belo Horizonte, Minas Gerais, CEP: 31270-901, Brazil.,Corresponding author: Department of General Pathology, Instituto de Ciências Biológicas, Bloco C3, Sala 102, Universidade Federal de Minas Gerais, Av. Antônio Carlos, 6627 Belo Horizonte–MG, Brazil 31270-901. Tel: +55 31 34092891.
| |
Collapse
|
4
|
Lemos FO, Guerra MT, Leite MDF. Inositol 1,4,5 trisphosphate receptors in secretory epithelial cells of the gastrointestinal tract. CURRENT OPINION IN PHYSIOLOGY 2020. [DOI: 10.1016/j.cophys.2020.08.003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
|
5
|
Li T, Tuo B. Pathophysiology of hepatic Na +/H + exchange (Review). Exp Ther Med 2020; 20:1220-1229. [PMID: 32742358 PMCID: PMC7388279 DOI: 10.3892/etm.2020.8888] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2019] [Accepted: 05/15/2020] [Indexed: 02/06/2023] Open
Abstract
Na+/H+ exchangers (NHEs) are a family of membrane proteins that contribute to exchanging one intracellular proton for one extracellular sodium. The family of NHEs consists of nine known members, NHE1-9. Each isoform represents a different gene product that has unique tissue expression, membrane localization, physiological effects, pathological regulation and sensitivity to drug inhibitors. NHE1 was the first to be discovered and is often referred to as the 'housekeeping' isoform of the NHE family. NHEs are not only involved in a variety of physiological processes, including the control of transepithelial Na+ absorption, intracellular pH, cell volume, cell proliferation, migration and apoptosis, but also modulate complex pathological events. Currently, the vast majority of review articles have focused on the role of members of the NHE family in inflammatory bowel disease, intestinal infectious diarrhea and digestive system tumorigenesis, but only a few reviews have discussed the role of NHEs in liver disease. Therefore, the present review described the basic biology of NHEs and highlighted their physiological and pathological effects in the liver.
Collapse
Affiliation(s)
- Tingting Li
- Department of Gastroenterology, Affiliated Hospital, Zunyi Medical University, Zunyi, Guizhou 563000, P.R. China
| | - Biguang Tuo
- Department of Gastroenterology, Affiliated Hospital, Zunyi Medical University, Zunyi, Guizhou 563000, P.R. China
| |
Collapse
|
6
|
Shin DH, Kim M, Kim Y, Jun I, Jung J, Nam JH, Cheng MH, Lee MG. Bicarbonate permeation through anion channels: its role in health and disease. Pflugers Arch 2020; 472:1003-1018. [PMID: 32621085 DOI: 10.1007/s00424-020-02425-x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2020] [Revised: 06/19/2020] [Accepted: 06/26/2020] [Indexed: 12/31/2022]
Abstract
Many anion channels, frequently referred as Cl- channels, are permeable to different anions in addition to Cl-. As the second-most abundant anion in the human body, HCO3- permeation via anion channels has many important physiological roles. In addition to its classical role as an intracellular pH regulator, HCO3- also controls the activity and stability of dissolved proteins in bodily fluids such as saliva, pancreatic juice, intestinal fluid, and airway surface liquid. Moreover, HCO3- permeation through these channels affects membrane potentials that are the driving forces for transmembrane transport of solutes and water in epithelia and affect neuronal excitability in nervous tissue. Consequently, aberrant HCO3- transport via anion channels causes a number of human diseases in respiratory, gastrointestinal, genitourinary, and neuronal systems. Notably, recent studies have shown that the HCO3- permeabilities of several anion channels are not fixed and can be altered by cellular stimuli, findings which may have both physiological and pathophysiological significance. In this review, we summarize recent progress in understanding the molecular mechanisms and the physiological roles of HCO3- permeation through anion channels. We hope that the present discussions can stimulate further research into this very important topic, which will provide the basis for human disorders associated with aberrant HCO3- transport.
Collapse
Affiliation(s)
- Dong Hoon Shin
- Department of Pharmacology, Brain Korea 21 PLUS Project for Medical Sciences, Severance Biomedical Science Institute, Yonsei University College of Medicine, Seoul, 03722, South Korea
| | - Minjae Kim
- Department of Pharmacology, Brain Korea 21 PLUS Project for Medical Sciences, Severance Biomedical Science Institute, Yonsei University College of Medicine, Seoul, 03722, South Korea
| | - Yonjung Kim
- Department of Pharmacology, Brain Korea 21 PLUS Project for Medical Sciences, Severance Biomedical Science Institute, Yonsei University College of Medicine, Seoul, 03722, South Korea
| | - Ikhyun Jun
- Department of Pharmacology, Brain Korea 21 PLUS Project for Medical Sciences, Severance Biomedical Science Institute, Yonsei University College of Medicine, Seoul, 03722, South Korea
- The Institute of Vision Research, Department of Ophthalmology, Yonsei University College of Medicine, Seoul, 03722, South Korea
| | - Jinsei Jung
- Department of Pharmacology, Brain Korea 21 PLUS Project for Medical Sciences, Severance Biomedical Science Institute, Yonsei University College of Medicine, Seoul, 03722, South Korea
- Department of Otorhinolaryngology, Yonsei University College of Medicine, Seoul, 03722, South Korea
| | - Joo Hyun Nam
- Department of Physiology, Dongguk University College of Medicine, 123 Dongdae-ro, Kyungju, 780-714, Republic of Korea
| | - Mary Hongying Cheng
- Department of Computational & Systems Biology, University of Pittsburgh, Pittsburgh, PA, USA
| | - Min Goo Lee
- Department of Pharmacology, Brain Korea 21 PLUS Project for Medical Sciences, Severance Biomedical Science Institute, Yonsei University College of Medicine, Seoul, 03722, South Korea.
| |
Collapse
|
7
|
Gilloteaux J. Primary cilia in the Syrian hamster biliary tract: Bile flow antennae and outlooks about signaling on the hepato-biliary-pancreatic stem cells. TRANSLATIONAL RESEARCH IN ANATOMY 2020. [DOI: 10.1016/j.tria.2020.100063] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
|
8
|
Sussman CR, Wang X, Chebib FT, Torres VE. Modulation of polycystic kidney disease by G-protein coupled receptors and cyclic AMP signaling. Cell Signal 2020; 72:109649. [PMID: 32335259 DOI: 10.1016/j.cellsig.2020.109649] [Citation(s) in RCA: 26] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2020] [Revised: 04/16/2020] [Accepted: 04/17/2020] [Indexed: 12/11/2022]
Abstract
Autosomal Dominant Polycystic Kidney Disease (ADPKD) is a systemic disorder associated with polycystic liver disease (PLD) and other extrarenal manifestations, the most common monogenic cause of end-stage kidney disease, and a major burden for public health. Many studies have shown that alterations in G-protein and cAMP signaling play a central role in its pathogenesis. As for many other diseases (35% of all approved drugs target G-protein coupled receptors (GPCRs) or proteins functioning upstream or downstream from GPCRs), treatments targeting GPCR have shown effectiveness in slowing the rate of progression of ADPKD. Tolvaptan, a vasopressin V2 receptor antagonist is the first drug approved by regulatory agencies to treat rapidly progressive ADPKD. Long-acting somatostatin analogs have also been effective in slowing the rates of growth of polycystic kidneys and liver. Although no treatment has so far been able to prevent the development or stop the progression of the disease, these encouraging advances point to G-protein and cAMP signaling as a promising avenue of investigation that may lead to more effective and safe treatments. This will require a better understanding of the relevant GPCRs, G-proteins, cAMP effectors, and of the enzymes and A-kinase anchoring proteins controlling the compartmentalization of cAMP signaling. The purpose of this review is to provide an overview of general GPCR signaling; the function of polycystin-1 (PC1) as a putative atypical adhesion GPCR (aGPCR); the roles of PC1, polycystin-2 (PC2) and the PC1-PC2 complex in the regulation of calcium and cAMP signaling; the cross-talk of calcium and cAMP signaling in PKD; and GPCRs, adenylyl cyclases, cyclic nucleotide phosphodiesterases, and protein kinase A as therapeutic targets in ADPKD.
Collapse
Affiliation(s)
- Caroline R Sussman
- Division of Nephrology and Hypertension, Mayo Clinic, Rochester, MN, United States of America
| | - Xiaofang Wang
- Division of Nephrology and Hypertension, Mayo Clinic, Rochester, MN, United States of America
| | - Fouad T Chebib
- Division of Nephrology and Hypertension, Mayo Clinic, Rochester, MN, United States of America
| | - Vicente E Torres
- Division of Nephrology and Hypertension, Mayo Clinic, Rochester, MN, United States of America.
| |
Collapse
|
9
|
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.
Collapse
|
10
|
Abstract
Cholangiocytes, the epithelial cells lining the intrahepatic and extrahepatic bile ducts, are highly specialized cells residing in a complex anatomic niche where they participate in bile production and homeostasis. Cholangiocytes are damaged in a variety of human diseases termed cholangiopathies, often causing advanced liver failure. The regulation of cholangiocyte transport properties is increasingly understood, as is their anatomical and functional heterogeneity along the biliary tract. Furthermore, cholangiocytes are pivotal in liver regeneration, especially when hepatocyte regeneration is compromised. The role of cholangiocytes in innate and adaptive immune responses, a critical subject relevant to immune-mediated cholangiopathies, is also emerging. Finally, reactive ductular cells are present in many cholestatic and other liver diseases. In chronic disease states, this repair response contributes to liver inflammation, fibrosis and carcinogenesis and is a subject of intense investigation. This Review highlights advances in cholangiocyte research, especially their role in development and liver regeneration, their functional and biochemical heterogeneity, their activation and involvement in inflammation and fibrosis and their engagement with the immune system. We aim to focus further attention on cholangiocyte pathobiology and the search for new disease-modifying therapies targeting the cholangiopathies.
Collapse
|
11
|
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.
Collapse
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
| |
Collapse
|
12
|
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.
Collapse
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.
| |
Collapse
|
13
|
Rodrigues PM, Perugorria MJ, Santos-Laso A, Bujanda L, Beuers U, Banales JM. Primary biliary cholangitis: A tale of epigenetically-induced secretory failure? J Hepatol 2018; 69:1371-1383. [PMID: 30193962 DOI: 10.1016/j.jhep.2018.08.020] [Citation(s) in RCA: 31] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/30/2018] [Revised: 08/14/2018] [Accepted: 08/24/2018] [Indexed: 12/16/2022]
Abstract
Primary biliary cholangitis (PBC) is a chronic cholestatic liver disease associated with autoimmune-related destruction of small to medium size intrahepatic bile ducts. The aetiology of PBC is unknown and its pathogenesis remains obscure. Both genetic variants and environmental factors have been linked to increased PBC susceptibility, with other alterations known to cooperate in disease pathobiology. Increasing evidence indicates the presence of epigenetic abnormalities in PBC, particularly alterations of cholangiocellular microRNAs (miRNAs or miRs). This review highlights and discusses the most relevant epigenetic alterations found in patients with PBC, focusing on the role of miR-506 in the promotion of cholestasis and immune activation.
Collapse
Affiliation(s)
- Pedro M Rodrigues
- Department of Liver and Gastrointestinal Diseases, Biodonostia Health Research Institute - Donostia University Hospital, University of the Basque Country (UPV/EHU), San Sebastian, Spain
| | - Maria J Perugorria
- Department of Liver and Gastrointestinal Diseases, Biodonostia Health Research Institute - Donostia University Hospital, University of the Basque Country (UPV/EHU), San Sebastian, Spain; National Institute for the Study of Liver and Gastrointestinal Diseases (CIBERehd, "Instituto de Salud Carlos III"), Spain; Ikerbasque, Basque Foundation for Science, Bilbao, Spain
| | - Alvaro Santos-Laso
- Department of Liver and Gastrointestinal Diseases, Biodonostia Health Research Institute - Donostia University Hospital, University of the Basque Country (UPV/EHU), San Sebastian, Spain
| | - Luis Bujanda
- Department of Liver and Gastrointestinal Diseases, Biodonostia Health Research Institute - Donostia University Hospital, University of the Basque Country (UPV/EHU), San Sebastian, Spain; National Institute for the Study of Liver and Gastrointestinal Diseases (CIBERehd, "Instituto de Salud Carlos III"), Spain
| | - Ulrich Beuers
- Tytgat Institute for Liver and Intestinal Research and Department of Gastroenterology & Hepatology, Amsterdam Gastroenterology and Metabolism, AMC, Amsterdam, The Netherlands
| | - Jesus M Banales
- Department of Liver and Gastrointestinal Diseases, Biodonostia Health Research Institute - Donostia University Hospital, University of the Basque Country (UPV/EHU), San Sebastian, Spain; National Institute for the Study of Liver and Gastrointestinal Diseases (CIBERehd, "Instituto de Salud Carlos III"), Spain; Ikerbasque, Basque Foundation for Science, Bilbao, Spain.
| |
Collapse
|
14
|
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.
Collapse
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.
| |
Collapse
|
15
|
Cheung AC, Lorenzo Pisarello MJ, LaRusso NF. Pathobiology of biliary epithelia. Biochim Biophys Acta Mol Basis Dis 2018; 1864:1220-1231. [PMID: 28716705 PMCID: PMC5777905 DOI: 10.1016/j.bbadis.2017.06.024] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2017] [Revised: 06/22/2017] [Accepted: 06/26/2017] [Indexed: 12/12/2022]
Abstract
Cholangiocytes are epithelial cells that line the intra- and extrahepatic biliary tree. They serve predominantly to mediate the content of luminal biliary fluid, which is controlled via numerous signaling pathways influenced by endogenous (e.g., bile acids, nucleotides, hormones, neurotransmitters) and exogenous (e.g., microbes/microbial products, drugs etc.) molecules. When injured, cholangiocytes undergo apoptosis/lysis, repair and proliferation. They also become senescent, a form of cell cycle arrest, which may prevent propagation of injury and/or malignant transformation. Senescent cholangiocytes can undergo further transformation to a senescence-associated secretory phenotype (SASP), where they begin secreting pro-inflammatory and pro-fibrotic signals that may contribute to disease initiation and progression. These and other concepts related to cholangiocyte pathobiology will be reviewed herein. 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.
Collapse
Affiliation(s)
- Angela C Cheung
- Division of Gastroenterology and Hepatology, Mayo Clinic Center for Cell Signaling in Gastroenterology, Mayo Clinic, Rochester, MN, United States
| | - Maria J Lorenzo Pisarello
- Division of Gastroenterology and Hepatology, Mayo Clinic Center for Cell Signaling in Gastroenterology, Mayo Clinic, Rochester, MN, United States
| | - Nicholas F LaRusso
- Division of Gastroenterology and Hepatology, Mayo Clinic Center for Cell Signaling in Gastroenterology, Mayo Clinic, Rochester, MN, United States.
| |
Collapse
|
16
|
Erice O, Munoz-Garrido P, Vaquero J, Perugorria MJ, Fernandez-Barrena MG, Saez E, Santos-Laso A, Arbelaiz A, Jimenez-Agüero R, Fernandez-Irigoyen J, Santamaria E, Torrano V, Carracedo A, Ananthanarayanan M, Marzioni M, Prieto J, Beuers U, Oude Elferink RP, LaRusso NF, Bujanda L, Marin JJG, Banales JM. MicroRNA-506 promotes primary biliary cholangitis-like features in cholangiocytes and immune activation. Hepatology 2018; 67:1420-1440. [PMID: 28922472 PMCID: PMC5857422 DOI: 10.1002/hep.29533] [Citation(s) in RCA: 63] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/03/2017] [Revised: 08/07/2017] [Accepted: 09/14/2017] [Indexed: 12/25/2022]
Abstract
Primary biliary cholangitis (PBC) is a chronic cholestatic liver disease associated with autoimmune phenomena targeting intrahepatic bile duct cells (cholangiocytes). Although its etiopathogenesis remains obscure, development of antimitochondrial autoantibodies against pyruvate dehydrogenase complex E2 is a common feature. MicroRNA (miR) dysregulation occurs in liver and immune cells of PBC patients, but its functional relevance is largely unknown. We previously reported that miR-506 is overexpressed in PBC cholangiocytes and directly targets both Cl- / HCO3- anion exchanger 2 and type III inositol 1,4,5-trisphosphate receptor, leading to cholestasis. Here, the regulation of miR-506 gene expression and its role in cholangiocyte pathophysiology and immune activation was studied. Several proinflammatory cytokines overexpressed in PBC livers (such as interleukin-8 [IL8], IL12, IL17, IL18, and tumor necrosis factor alpha) stimulated miR-506 promoter activity in human cholangiocytes, as revealed by luciferase reporter assays. Experimental overexpression of miR-506 in cholangiocytes dysregulated the cell proteomic profile (by mass spectrometry), affecting proteins involved in different biological processes including mitochondrial metabolism. In cholangiocytes, miR-506 (1) induced dedifferentiation with down-regulation of biliary and epithelial markers together with up-regulation of mesenchymal, proinflammatory, and profibrotic markers; (2) impaired cell proliferation and adhesion; (3) increased oxidative and endoplasmic reticulum stress; (4) caused DNA damage; and (5) sensitized to caspase-3-dependent apoptosis induced by cytotoxic bile acids. These events were also associated with impaired energy metabolism in mitochondria (proton leak and less adenosine triphosphate production) and pyruvate dehydrogenase complex E2 overexpression. Coculture of miR-506 overexpressing cholangiocytes with PBC immunocytes induced activation and proliferation of PBC immunocytes. CONCLUSION Different proinflammatory cytokines enhance the expression of miR-506 in biliary epithelial cells; miR-506 induces PBC-like features in cholangiocytes and promotes immune activation, representing a potential therapeutic target for PBC patients. (Hepatology 2018;67:1420-1440).
Collapse
Affiliation(s)
- Oihane Erice
- Department of Liver and Gastrointestinal Diseases, Biodonostia Research Institute-Donostia University Hospital, University of the Basque Country (UPV/EHU), San Sebastian, Spain
| | - Patricia Munoz-Garrido
- Department of Liver and Gastrointestinal Diseases, Biodonostia Research Institute-Donostia University Hospital, University of the Basque Country (UPV/EHU), San Sebastian, Spain
- National Institute for the Study of Liver and Gastrointestinal Diseases (CIBERehd), Carlos III National Institute of Health, Madrid, Spain
| | - Javier Vaquero
- Experimental Hepatology and Drug Targeting (HEVEFARM), Biomedical Research Institute of Salamanca (IBSAL), University of Salamanca, Salamanca, Spain
- Sorbonne Universités, UPMC Université Paris 06, INSERM, Saint-Antoine Research Center, Paris, and Fondation ARC, Villejuif, France
| | - Maria J Perugorria
- Department of Liver and Gastrointestinal Diseases, Biodonostia Research Institute-Donostia University Hospital, University of the Basque Country (UPV/EHU), San Sebastian, Spain
- National Institute for the Study of Liver and Gastrointestinal Diseases (CIBERehd), Carlos III National Institute of Health, Madrid, Spain
- IKERBASQUE, Basque Foundation for Science, Bilbao, Spain
| | - Maite G Fernandez-Barrena
- National Institute for the Study of Liver and Gastrointestinal Diseases (CIBERehd), Carlos III National Institute of Health, Madrid, Spain
- Division of Hepatology, CIMA of the University of Navarra, Pamplona, Spain
| | - Elena Saez
- Division of Hepatology, CIMA of the University of Navarra, Pamplona, Spain
| | - Alvaro Santos-Laso
- Department of Liver and Gastrointestinal Diseases, Biodonostia Research Institute-Donostia University Hospital, University of the Basque Country (UPV/EHU), San Sebastian, Spain
| | - Ander Arbelaiz
- Department of Liver and Gastrointestinal Diseases, Biodonostia Research Institute-Donostia University Hospital, University of the Basque Country (UPV/EHU), San Sebastian, Spain
| | - Raul Jimenez-Agüero
- Department of Liver and Gastrointestinal Diseases, Biodonostia Research Institute-Donostia University Hospital, University of the Basque Country (UPV/EHU), San Sebastian, Spain
| | - Joaquin Fernandez-Irigoyen
- Proteored-ISCIII, Proteomics Unit, Navarrabiomed, Navarra Health Department, Public University of Navarra, Navarra Institute for Health Research (IdiSNA), Pamplona, Spain
| | - Enrique Santamaria
- Proteored-ISCIII, Proteomics Unit, Navarrabiomed, Navarra Health Department, Public University of Navarra, Navarra Institute for Health Research (IdiSNA), Pamplona, Spain
| | - Verónica Torrano
- CIC bioGUNE, Bizkaia Technology Park, Derio, Bizkaia, Spain
- CIBERONC
| | - Arkaitz Carracedo
- IKERBASQUE, Basque Foundation for Science, Bilbao, Spain
- CIC bioGUNE, Bizkaia Technology Park, Derio, Bizkaia, Spain
- CIBERONC
- Biochemistry and Molecular Biology Department, University of the Basque Country (UPV/EHU), Bilbao, Spain
| | | | - Marco Marzioni
- Department of Gastroenterology, Università Politecnica delle Marche, Ancona, Italy
| | - Jesus Prieto
- National Institute for the Study of Liver and Gastrointestinal Diseases (CIBERehd), Carlos III National Institute of Health, Madrid, Spain
- Division of Hepatology, CIMA of the University of Navarra, Pamplona, Spain
| | - Ulrich Beuers
- Department of Gastroenterology and Hepatology, Tytgat Institute for Liver and Intestinal Research, Academic Medical Centre, University of Amsterdam, Amsterdam, The Netherlands
| | - Ronald P Oude Elferink
- Department of Gastroenterology and Hepatology, Tytgat Institute for Liver and Intestinal Research, Academic Medical Centre, University of Amsterdam, Amsterdam, The Netherlands
| | | | - Luis Bujanda
- Department of Liver and Gastrointestinal Diseases, Biodonostia Research Institute-Donostia University Hospital, University of the Basque Country (UPV/EHU), San Sebastian, Spain
- National Institute for the Study of Liver and Gastrointestinal Diseases (CIBERehd), Carlos III National Institute of Health, Madrid, Spain
| | - Jose J G Marin
- National Institute for the Study of Liver and Gastrointestinal Diseases (CIBERehd), Carlos III National Institute of Health, Madrid, Spain
- Experimental Hepatology and Drug Targeting (HEVEFARM), Biomedical Research Institute of Salamanca (IBSAL), University of Salamanca, Salamanca, Spain
| | - 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
- National Institute for the Study of Liver and Gastrointestinal Diseases (CIBERehd), Carlos III National Institute of Health, Madrid, Spain
- IKERBASQUE, Basque Foundation for Science, Bilbao, Spain
| |
Collapse
|
17
|
't Hart NA, van der Plaats A, Moers C, Leuvenink HGD, Wiersema-Buist J, Verkerke GJ, Rakhorst G, Ploeg RJ. Development of the Isolated Dual Perfused Rat Liver Model as an Improved Reperfusion Model for Transplantation Research. Int J Artif Organs 2018; 29:219-27. [PMID: 16552669 DOI: 10.1177/039139880602900208] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
The Isolated Perfused Liver (IPL) model is a widely used and appreciated in vitro method to demonstrate liver viability and metabolism. Reperfusion is performed in a controlled setting, however, via the portal vein only. To study transplant related questions concerning bile and transport of bile, the in vitro Isolated dual Perfused Liver model is revisited. The IdPL is an in vitro reperfusion model, using both portal vein and hepatic artery. Livers from 12 Wistar rats were flushed with University of Wisconsin-organ preservation solution, procured and reperfused in either the conventional IPL-model (n=6) or the new IdPL-model (n=6). Liver injury, assessed by the release of aspartate amino transferase and lactate dehydrogenase, showed similar levels during both IPL and IdPL reperfusion, only alanine amino transferase showed an improvement. Cumulative bile production showed an improvement: 176.3 ± 8.4 in the IdPL compared to 126.1 ± 12.2 μg/g-liver in the IPL (p<0.05). Clearance of phenol red (PR) and taurocholic acid (TC) remained similar. At 90 minutes reperfusion the PR clearance showed 0.11 ± 0.01 and 0.11 ± 0.02 mg/30min/g-liver and the TC clearance 1.01 ± 0.10 and 1.01 ± 0.07 μmol/ml/30min/g-liver in the IPL and IdPL, respectively. Increasing the reperfusion time beyond the normally used 90 minutes resulted in a significant increase in transaminases and LDH and a decrease in bile production, liver morphology remained intact and glycogen content was appropriate. In conclusion, the IdPL-model showed similar or better results than the IPL-model, but the liver could not endure an extended reperfusion time using the IdPL.
Collapse
Affiliation(s)
- N A 't Hart
- Surgery Research Laboratory, University of Groningen, Groningen, The Netherlands.
| | | | | | | | | | | | | | | |
Collapse
|
18
|
Weerachayaphorn J, Amaya MJ, Spirli C, Chansela P, Mitchell KA, Ananthanarayanan M, Nathanson MH. Nuclear Factor, Erythroid 2-Like 2 Regulates Expression of Type 3 Inositol 1,4,5-Trisphosphate Receptor and Calcium Signaling in Cholangiocytes. Gastroenterology 2015; 149:211-222.e10. [PMID: 25796361 PMCID: PMC4478166 DOI: 10.1053/j.gastro.2015.03.014] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/14/2014] [Revised: 02/27/2015] [Accepted: 03/13/2015] [Indexed: 12/17/2022]
Abstract
BACKGROUND & AIMS Most cholestatic disorders are caused by defects in cholangiocytes. The type 3 isoform of the inositol 1,4,5-trisphosphate receptor (ITPR3) is the most abundant intracellular calcium release channel in cholangiocytes. ITPR3 is required for bicarbonate secretion by bile ducts, and its expression is reduced in intrahepatic bile ducts of patients with cholestatic disorders. We investigated whether the nuclear factor, erythroid 2-like 2 (NFE2L2 or NRF2), which is sensitive to oxidative stress, regulates expression of ITPR3. METHODS The activity of the ITPR3 promoter was measured in normal human cholangiocyte (NHC) cells and primary mouse cholangiocytes. Levels of ITPR3 protein and messenger RNA were examined by immunoblot and polymerase chain reaction analyses, respectively. ITPR3 activity was determined by measuring calcium signaling in normal human cholangiocyte cells and secretion in isolated bile duct units. Levels of NRF2 were measured in liver tissues from rats with cholestasis (induced by administration of α-napthylisothiocyanate) and from patients with biliary diseases. RESULTS We identified a musculo-aponeurotic fibrosarcoma recognition element in the promoter of ITPR3 that bound NRF2 directly in NHC cells and mouse cholangiocytes. Increasing binding of NRF2 at this site resulted in chromatin remodeling that reduced promoter activity. Mutant forms of the musculo-aponeurotic fibrosarcoma recognition element did not bind NRF2. Activation of NRF2 with quercetin or by oxidative stress reduced expression of ITPR3 and calcium signaling in NHC cells; quercetin also reduced secretion by bile duct units isolated from rats. Knockdown of NRF2 with small interfering RNAs restored expression and function of ITPR3 in NHC cells incubated with quercetin. Bile ducts from rats with cholestasis and patients with cholangiopathic disorders expressed higher levels of NRF2 and lower levels of ITPR3 than ducts from control rats or patients with other liver disorders. CONCLUSIONS The transcription factor NRF2 binds to the promoter of ITPR3 to inhibit its expression in cholangiocytes, leading to reduced calcium signaling and bile duct secretion. This could be a mechanism by which oxidative stress inhibits these processes and contributes to cholangiopathies.
Collapse
Affiliation(s)
- Jittima Weerachayaphorn
- Liver Center, Yale University School of Medicine, New Haven, Connecticut, USA,Department of Physiology, Faculty of Science, Mahidol University, Bangkok, Thailand
| | - Maria Jimena Amaya
- Liver Center, Yale University School of Medicine, New Haven, Connecticut, USA
| | - Carlo Spirli
- Liver Center, Yale University School of Medicine, New Haven, Connecticut, USA
| | - Piyachat Chansela
- Department of Anatomy, Phramongkutklao College of Medicine, Bangkok, Thailand
| | - Kisha A. Mitchell
- Department of Pathology, Yale University School of Medicine, New Haven, Connecticut, USA
| | | | - Michael H. Nathanson
- Liver Center, Yale University School of Medicine, New Haven, Connecticut, USA,Corresponding Author: Michael H. Nathanson MD., PhD., Department of Medicine, Section of Digestive Diseases, Yale University School of Medicine, 333 Cedar Street, TAC S241D, New Haven, CT, 06519 USA, Tel: (203)-785-7312, Fax: (203)-785-7273,
| |
Collapse
|
19
|
Ananthanarayanan M, Banales JM, Guerra MT, Spirli C, Munoz-Garrido P, Mitchell-Richards K, Tafur D, Saez E, Nathanson MH. Post-translational regulation of the type III inositol 1,4,5-trisphosphate receptor by miRNA-506. J Biol Chem 2014; 290:184-96. [PMID: 25378392 DOI: 10.1074/jbc.m114.587030] [Citation(s) in RCA: 60] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
The type III isoform of the inositol 1,4,5-trisphosphate receptor (InsP3R3) is apically localized and triggers Ca(2+) waves and secretion in a number of polarized epithelia. However, nothing is known about epigenetic regulation of this InsP3R isoform. We investigated miRNA regulation of InsP3R3 in primary bile duct epithelia (cholangiocytes) and in the H69 cholangiocyte cell line, because the role of InsP3R3 in cholangiocyte Ca(2+) signaling and secretion is well established and because loss of InsP3R3 from cholangiocytes is responsible for the impairment in bile secretion that occurs in a number of liver diseases. Analysis of the 3'-UTR of human InsP3R3 mRNA revealed two highly conserved binding sites for miR-506. Transfection of miR-506 mimics into cell lines expressing InsP3R3-3'UTR-luciferase led to decreased reporter activity, whereas co-transfection with miR-506 inhibitors led to enhanced activity. Reporter activity was abrogated in isolated mutant proximal or distal miR-506 constructs in miR-506-transfected HEK293 cells. InsP3R3 protein levels were decreased by miR-506 mimics and increased by inhibitors, and InsP3R3 expression was markedly decreased in H69 cells stably transfected with miR-506 relative to control cells. miR-506-H69 cells exhibited a fibrotic signature. In situ hybridization revealed elevated miR-506 expression in vivo in human-diseased cholangiocytes. Histamine-induced, InsP3-mediated Ca(2+) signals were decreased by 50% in stable miR-506 cells compared with controls. Finally, InsP3R3-mediated fluid secretion was significantly decreased in isolated bile duct units transfected with miR-506, relative to control IBDU. Together, these data identify miR-506 as a regulator of InsP3R3 expression and InsP3R3-mediated Ca(2+) signaling and secretion.
Collapse
Affiliation(s)
| | - Jesus M Banales
- the Department of Liver and Gastrointestinal Diseases, Biodonostia Research Institute, Donostia University Hospital, University of Basque Country (UPV/EHU), CIBERehd, IKERBASQUE, AECC, 20014 San Sebastian, Spain, and the Division of Gene Therapy and Hepatology, CIMA of the University of Navarra, Ciberehd, 31009 Pamplona, Spain
| | | | | | - Patricia Munoz-Garrido
- the Department of Liver and Gastrointestinal Diseases, Biodonostia Research Institute, Donostia University Hospital, University of Basque Country (UPV/EHU), CIBERehd, IKERBASQUE, AECC, 20014 San Sebastian, Spain, and
| | - Kisha Mitchell-Richards
- Pathology, Section of Digestive Diseases and the Liver Center, Yale University School of Medicine, New Haven, Connecticut 06520
| | | | - Elena Saez
- the Division of Gene Therapy and Hepatology, CIMA of the University of Navarra, Ciberehd, 31009 Pamplona, Spain
| | | |
Collapse
|
20
|
Cai JS, Chen JH. The mechanism of enterohepatic circulation in the formation of gallstone disease. J Membr Biol 2014; 247:1067-82. [PMID: 25107305 PMCID: PMC4207937 DOI: 10.1007/s00232-014-9715-3] [Citation(s) in RCA: 45] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2014] [Accepted: 07/25/2014] [Indexed: 12/25/2022]
Abstract
Bile acids entering into enterohepatic circulating are primary acids synthesized from cholesterol in hepatocyte. They are secreted actively across canalicular membrane and carried in bile to gallbladder, where they are concentrated during digestion. About 95 % BAs are actively taken up from the lumen of terminal ileum efficiently, leaving only approximately 5 % (or approximately 0.5 g/d) in colon, and a fraction of bile acids are passively reabsorbed after a series of modifications in the human large intestine including deconjugation and oxidation of hydroxy groups. Bile salts hydrolysis and hydroxy group dehydrogenation reactions are performed by a broad spectrum of intestinal anaerobic bacteria. Next, hepatocyte reabsorbs bile acids from sinusoidal blood, which are carried to liver through portal vein via a series of transporters. Bile acids (BAs) transporters are critical for maintenance of the enterohepatic BAs circulation, where BAs exert their multiple physiological functions including stimulation of bile flow, intestinal absorption of lipophilic nutrients, solubilization, and excretion of cholesterol. Tight regulation of BA transporters via nuclear receptors (NRs) is necessary to maintain proper BA homeostasis. In conclusion, disturbances of enterohepatic circulation may account for pathogenesis of gallstones diseases, including BAs transporters and their regulatory NRs and the metabolism of intestinal bacterias, etc.
Collapse
Affiliation(s)
- Jian-Shan Cai
- Department of General Surgery, Huashan Hospital, Fudan University, 12 Wulumuqi Road, Shanghai, 200040, People's Republic of China,
| | | |
Collapse
|
21
|
Jung J, Lee MG. Role of calcium signaling in epithelial bicarbonate secretion. Cell Calcium 2014; 55:376-84. [PMID: 24598807 DOI: 10.1016/j.ceca.2014.02.002] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2014] [Revised: 02/03/2014] [Accepted: 02/04/2014] [Indexed: 12/24/2022]
Abstract
Transepithelial bicarbonate secretion plays a key role in the maintenance of fluid and protein secretion from epithelial cells and the protection of the epithelial cell surface from various pathogens. Epithelial bicarbonate secretion is mainly under the control of cAMP and calcium signaling. While the physiological roles and molecular mechanisms of cAMP-induced bicarbonate secretion are relatively well defined, those induced by calcium signaling remain poorly understood in most epithelia. The present review summarizes the current status of knowledge on the role of calcium signaling in epithelial bicarbonate secretion. Specifically, this review introduces how cytosolic calcium signaling can increase bicarbonate secretion by regulating membrane transport proteins and how it synergizes with cAMP-induced mechanisms in epithelial cells. In addition, tissue-specific variations in the pancreas, salivary glands, intestines, bile ducts, and airways are discussed. We hope that the present report will stimulate further research into this important topic. These studies will provide the basis for future medicines for a wide spectrum of epithelial disorders including cystic fibrosis, Sjögren's syndrome, and chronic pancreatitis.
Collapse
Affiliation(s)
- Jinsei Jung
- Department of Pharmacology and Brain Korea 21 Plus Project for Medical Sciences, Yonsei University College of Medicine, Seoul 120-752, Republic of Korea; Department of Otorhinolaryngology, Yonsei University College of Medicine, Seoul 120-752, Republic of Korea
| | - Min Goo Lee
- Department of Pharmacology and Brain Korea 21 Plus Project for Medical Sciences, Yonsei University College of Medicine, Seoul 120-752, Republic of Korea.
| |
Collapse
|
22
|
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.
Collapse
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.
| |
Collapse
|
23
|
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.
Collapse
Affiliation(s)
- Maria Jimena Amaya
- Section of Digestive Diseases, Department of Internal Medicine, Yale University School of Medicine, New Haven, Connecticut, USA
| | | |
Collapse
|
24
|
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: 151] [Impact Index Per Article: 13.7] [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.
Collapse
|
25
|
Wang X, Ye H, Ward CJ, Chu JYS, Masyuk TV, Larusso NF, Harris PC, Chow BKC, Torres VE. Insignificant effect of secretin in rodent models of polycystic kidney and liver disease. Am J Physiol Renal Physiol 2012; 303:F1089-98. [PMID: 22811488 DOI: 10.1152/ajprenal.00242.2012] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
Polycystic kidney (PKD) and liver (PLD) diseases cause significant morbidity and mortality. A large body of evidence indicates that cyclic AMP plays an important role in their pathogenesis. Clinical trials of drugs that reduce cyclic AMP levels in target tissues are now in progress. Secretin may contribute to adenylyl cyclase-dependent urinary concentration and is a major agonist of adenylyl cyclase in cholangiocytes. To investigate the role of secretin in PKD and PLD, we have studied the expression of secretin and the secretin receptor in rodent models orthologous to autosomal recessive (PCK rat) and dominant (Pkd2(-/WS25) mouse) PKD; the effects of exogenous secretin administration to PCK rats, PCK rats lacking circulating vasopressin (PCK(di/di)), and Pkd2(-/WS25) mice; and the impact of a nonfunctional secretin receptor on disease development in Pkd2(-/WS25):SCTR(-/-) double mutants. Renal and hepatic secretin and secretin receptor mRNA and plasma secretin were increased in both models, and secretin receptor protein was increased in the kidneys and liver of Pkd2(-/WS25) mice. However, exogenous secretin administered subcutaneously via osmotic pumps had minimal or negligible effects and the absence of a functional secretin receptor had no influence on the severity of PKD or PLD. Therefore, it is unlikely that by itself secretin plays a significant role in the pathogenesis of PKD and/or PLD.
Collapse
Affiliation(s)
- Xiaofang Wang
- Mayo Clinic, 200 First St SW, Rochester, MN 55905, USA
| | | | | | | | | | | | | | | | | |
Collapse
|
26
|
Abstract
The formation of bile depends on the structural and functional integrity of the bile-secretory apparatus and its impairment, in different situations, results in the syndrome of cholestasis. The structural bases that permit bile secretion as well as various aspects related with its composition and flow rate in physiological conditions will first be reviewed. Canalicular bile is produced by polarized hepatocytes that hold transporters in their basolateral (sinusoidal) and apical (canalicular) plasma membrane. This review summarizes recent data on the molecular determinants of this primary bile formation. The major function of the biliary tree is modification of canalicular bile by secretory and reabsorptive processes in bile-duct epithelial cells (cholangiocytes) as bile passes through bile ducts. The mechanisms of fluid and solute transport in cholangiocytes will also be discussed. In contrast to hepatocytes where secretion is constant and poorly controlled, cholangiocyte secretion is regulated by hormones and nerves. A short section dedicated to these regulatory mechanisms of bile secretion has been included. The aim of this revision was to set the bases for other reviews in this series that will be devoted to specific issues related with biliary physiology and pathology.
Collapse
|
27
|
Fiorotto R, Spirlì C, Fabris L, Cadamuro M, Okolicsanyi L, Strazzabosco M. Ursodeoxycholic acid stimulates cholangiocyte fluid secretion in mice via CFTR-dependent ATP secretion. Gastroenterology 2007; 133:1603-13. [PMID: 17983806 DOI: 10.1053/j.gastro.2007.08.071] [Citation(s) in RCA: 93] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/26/2006] [Accepted: 07/26/2007] [Indexed: 12/02/2022]
Abstract
BACKGROUND & AIMS Cholangiopathies are characterized by impaired cholangiocyte secretion. Ursodeoxycholic acid (UDCA) is widely used for cholangiopathy treatment, but its effects on cholangiocyte secretory functions remain unclear and are the subject of this study. METHODS Polarized mouse cholangiocytes in tubular (isolated bile-duct units [IBDU]) or monolayer configuration were obtained from wild-type (WT) and B6-129-Cftr(tm1Kth) and Cftr(tm1Unc) mice that are defective in CFTR, an adenosine 3',5'-cyclic monophosphate (cAMP)-stimulated Cl(-) channel expressed in cholangiocytes. Fluid secretion was assessed by video-optical planimetry, Cl(-) and Ca(2+) efflux by microfluorimetry (6-methoxy-N-ethylquinolinium chloride, fura-2, and fluo-4), adenosine triphosphate (ATP) secretion by luciferin-luciferase assay, and protein kinase C (PKC) by Western blot. RESULTS UDCA stimulated fluid secretion and Cl(-) efflux in WT-IBDU but not in CFTR-KO-IBDU or in WT-IBDU exposed to CFTR inhibitors. UDCA did not affect intracellular cAMP levels but increased [Ca(2+)]i in WT and not in CFTR-KO cholangiocytes. UDCA stimulated apical ATP secretion in WT but not in CFTR-KO cholangiocytes. UDCA-stimulated [Ca(2+)]i increase was inhibited by suramin, a purinergic 2Y-receptor inhibitor. UDCA stimulated the translocation of PKC-alpha and PKC-epsilon to the plasma membrane. UDCA-stimulated secretion was inhibited by 2-bis(2-aminophenoxy)-ethane-N,N,N',N'-tetraacetic acid and by phospholipase C and PKC inhibitors. UDCA increased ATP output in isolated perfused livers from WT but not from CFTR-KO mice. CONCLUSIONS Our data indicate that UDCA stimulates a CFTR-dependent apical ATP release in cholangiocytes. Secreted ATP activates purinergic 2Y receptors, and, through [Ca(2+)]i increase and PKC activation stimulates Cl(-) efflux and fluid secretion. These data support the concept that CFTR plays a role in modulating purinergic signaling in secretory epithelia and suggest a novel mechanism explaining the choleretic effect of UDCA.
Collapse
Affiliation(s)
- Romina Fiorotto
- Department of Internal Medicine, Section of Digestive Diseases, Yale University School of Medicine and Liver Center, New Haven, Connecticut, USA
| | | | | | | | | | | |
Collapse
|
28
|
Minagawa N, Nagata J, Shibao K, Masyuk AI, Gomes DA, Rodrigues MA, LeSage G, Akiba Y, Kaunitz JD, Ehrlich BE, LaRusso NF, Nathanson MH. Cyclic AMP regulates bicarbonate secretion in cholangiocytes through release of ATP into bile. Gastroenterology 2007; 133:1592-602. [PMID: 17916355 PMCID: PMC2128713 DOI: 10.1053/j.gastro.2007.08.020] [Citation(s) in RCA: 105] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/27/2006] [Accepted: 07/02/2007] [Indexed: 01/07/2023]
Abstract
BACKGROUND & AIMS Bicarbonate secretion is a primary function of cholangiocytes. Either adenosine 3',5'-cyclic monophosphate (cAMP) or cytosolic Ca(2+) can mediate bicarbonate secretion, but these are thought to act through separate pathways. We examined the role of the inositol 1,4,5-trisphosphate receptor (InsP3R) in mediating bicarbonate secretion because this is the only intracellular Ca(2+) release channel in cholangiocytes. METHODS Intrahepatic bile duct units (IBDUs) were microdissected from rat liver then luminal pH was examined by confocal microscopy during IBDU microperfusion. Cyclic AMP was increased using forskolin or secretin, and Ca(2+) was increased using acetylcholine (ACh) or adenosine triphosphate (ATP). Apyrase was used to hydrolyze extracellular ATP, and suramin was used to block apical P2Y ATP receptors. In selected experiments, IBDUs were pretreated with short interfering RNA (siRNA) to silence expression of specific InsP3R isoforms. RESULTS Both cAMP and Ca(2+) agonists increased luminal pH. The effect of ACh on luminal pH was reduced by siRNA for basolateral (types I and II) but not apical (type III) InsP3R isoforms. The effect of forskolin on luminal pH was reduced by a cystic fibrosis transmembrane conductance regulator (CFTR) inhibitor and by siRNA for the type III InsP3R. Luminal apyrase or suramin blocked the effects of forskolin but not ACh on luminal pH. CONCLUSIONS Cyclic AMP-induced ductular bicarbonate secretion depends on an autocrine signaling pathway that involves CFTR, apical release of ATP, stimulation of apical nucleotide receptors, and then activation of apical, type III InsP3Rs. The primary role of CFTR in bile duct secretion may be to regulate secretion of ATP rather than to secrete chloride and/or bicarbonate.
Collapse
Affiliation(s)
- Noritaka Minagawa
- Department of Medicine, Yale University School of Medicine, New Haven, CT, Department of Surgery 1, University of Occupational and Environmental Health, Kitakyushu, Japan
| | - Jun Nagata
- Department of Medicine, Yale University School of Medicine, New Haven, CT, Department of Surgery 1, University of Occupational and Environmental Health, Kitakyushu, Japan
| | - Kazunori Shibao
- Department of Medicine, Yale University School of Medicine, New Haven, CT, Department of Surgery 1, University of Occupational and Environmental Health, Kitakyushu, Japan
| | | | - Dawidson A. Gomes
- Department of Medicine, Yale University School of Medicine, New Haven, CT
| | | | - Gene LeSage
- Department of Medicine, University of Texas, Houston, TX
| | - Yasutada Akiba
- Department of Medicine, University of California, Los Angeles, CA
| | | | - Barbara E. Ehrlich
- Department of Pharmacology, Yale University School of Medicine, New Haven, CT
| | | | - Michael H. Nathanson
- Department of Medicine, Yale University School of Medicine, New Haven, CT,7Address for correspondence: Michael H. Nathanson, Digestive Diseases, Room TAC S241D, Yale University School of Medicine, New Haven, CT 06520-8019, Phone 203-785-7312, FAX 203-785-4306,
| |
Collapse
|
29
|
Correa PRAV, Kruglov EA, Thompson M, Leite MF, Dranoff JA, Nathanson MH. Succinate is a paracrine signal for liver damage. J Hepatol 2007; 47:262-9. [PMID: 17451837 PMCID: PMC1986575 DOI: 10.1016/j.jhep.2007.03.016] [Citation(s) in RCA: 119] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/12/2006] [Revised: 01/23/2007] [Accepted: 03/10/2007] [Indexed: 01/17/2023]
Abstract
BACKGROUND/AIMS A G-protein-coupled succinate receptor has recently been identified in several tissues, including the liver. The objectives of this work were to determine the hepatic cell types that express this receptor and to determine its physiological role. METHODS Expression and distribution of the succinate receptor was determined by RT-PCR and confocal immunofluorescence. Biochemical assays were used to measure succinate and cAMP. Cytosolic Ca2+ was monitored in single cells by time-lapse imaging. Western blot was used to study the effect of succinate on activation of hepatic stellate cells. RESULTS The succinate receptor was expressed in quiescent hepatic stellate cells, and expression decreased with activation. Ischemia induced release of succinate in isolated perfused livers. In contrast to what is observed in cell expression systems, succinate did not inhibit cAMP production or increase cytosolic Ca2+ in primary hepatic stellate cells. However, succinate accelerated stellate cell activation. CONCLUSIONS Hepatic stellate cells express the succinate receptor. Succinate may behave as a paracrine signal by which ischemic hepatocytes trigger stellate cell activation.
Collapse
Affiliation(s)
- Paulo Renato A V Correa
- Section of Digestive Diseases, Department of Internal Medicine, Room TAC S241D, Yale University School of Medicine, New Haven, CT 06520-8019, USA
| | | | | | | | | | | |
Collapse
|
30
|
Elsing C, Gosch I, Hennings JC, Hübner CA, Herrmann T. Mechanisms of hypotonic inhibition of the sodium, proton exchanger type 1 (NHE1) in a biliary epithelial cell line (Mz-Cha-1). Acta Physiol (Oxf) 2007; 190:199-208. [PMID: 17581135 DOI: 10.1111/j.1748-1716.2007.01682.x] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
AIM To elucidate the cellular events that results in inhibition of Na(+), H(+) exchanger type 1 (NHE1) by hypotonicity. METHODS Intracellular pH (pH(i)) was measured in biliary epithelial cells, with the pH-sensitive fluorochrome 2',7'-bis-(carboxyethyl)-5(6)-carboxyfluorescein (BCECF) using a spectrophotometer. Regulatory volume decrease (RVD) was analysed from confocal images. Changes in NHE1 membrane content were visualized by confocal laser scanning microscopy after transfection of Mz-Cha-1 cells with a NHE1-cMyc fusion protein. RESULTS In Mz-Cha-1 cells hypotonicity (-80 mmol L(-1) NaCl) inhibited endogenous Na(+), H(+) exchange. Tyrosine and serine kinase inhibitors were incapable to prevent inhibition. As several signalling pathways influence Na(+), H(+) exchange, we tested the effect of the Ca(++), Calmodulin, protein kinase C or the cAMP, protein kinase A system on inhibition of Na(+), H(+) exchange by hypotonic challenge, but neither system was involved. In contrast, cytoskeleton did influence the effect of hypotonicity. Inhibition of microtubule polymerization by colchicine prevented inhibition of NHE1, and also restored Na(+), H(+) exchange kinetics. Specific inhibition of Src kinases with PP2, attenuated pH(i) recovery rate from 1.93 +/- 0.16 pH units min(-1) (normotonic environment) to 1.02 +/- 0.50 pH units min(-1) (hypotonic environment). Membrane staining of NHE1-cMyc fusion protein was maintained after hypotonic exposure in colchicine pre-treated cells as was RVD. Microfilament inhibition by cytochalasin preserved NHE1 activity. Inhibition of phosphatidylinositol-3'-kinase was unable to restore Na(+), H(+) exchange activity. CONCLUSION We conclude that regulation of Na(+), H(+) exchange during RVD is mediated by cytoskeletal elements. This receptor independent pathway is regulated by Src.
Collapse
Affiliation(s)
- C Elsing
- Department of Gastroenterology, St Elisabeth Hospital, Dorsten, Germany
| | | | | | | | | |
Collapse
|
31
|
Elsing C, Gosch I, Hennings JC, Hübner CA, Herrmann T. Mechanisms of hypotonic inhibition of the sodium, proton exchanger type 1 (NHE1) in a biliary epithelial cell line (Mz-Cha-1). Acta Physiol (Oxf) 2007. [DOI: 10.1111/j.1365-201x.2007.01682.x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
|
32
|
Minagawa N, Ehrlich BE, Nathanson MH. Calcium signaling in cholangiocytes. World J Gastroenterol 2006; 12:3466-70. [PMID: 16773703 PMCID: PMC4087562 DOI: 10.3748/wjg.v12.i22.3466] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/01/2006] [Revised: 01/14/2006] [Accepted: 01/24/2006] [Indexed: 02/06/2023] Open
Abstract
Cytosolic Ca2+ is an important second messenger in virtually every type of cell. Moreover, Ca2+ generally regulates multiple activities within individual cells. This article reviews the cellular machinery that is responsible for Ca2+ signaling in cholangiocytes. In addition, two Ca2+-mediated events in cholangiocytes are discussed: bicarbonate secretion and apoptosis. Finally, emerging evidence is reviewed that Ca2+ signaling is involved in the pathogenesis of diseases affecting the biliary tree and that Ca2+ signaling pathways can be manipulated to therapeutic advantage in the treatment of cholestatic disorders.
Collapse
Affiliation(s)
- Noritaka Minagawa
- Department of Medicine Pharmacology, Yale University School of Medicine, 1 Gilbert Street, Room TAC S241D, New Haven, CT 06519, USA
| | | | | |
Collapse
|
33
|
Abstract
Primary canalicular bile undergoes a process of fluidization and alkalinization along the biliary tract that is influenced by several factors including hormones, innervation/neuropeptides, and biliary constituents. The excretion of bicarbonate at both the canaliculi and the bile ducts is an important contributor to the generation of the so-called bile-salt independent flow. Bicarbonate is secreted from hepatocytes and cholangiocytes through parallel mechanisms which involve chloride efflux through activation of Cl- channels, and further bicarbonate secretion via AE2/SLC4A2-mediated Cl-/HCO3- exchange. Glucagon and secretin are two relevant hormones which seem to act very similarly in their target cells (hepatocytes for the former and cholangiocytes for the latter). These hormones interact with their specific G protein-coupled receptors, causing increases in intracellular levels of cAMP and activation of cAMP-dependent Cl- and HCO3- secretory mechanisms. Both hepatocytes and cholangiocytes appear to have cAMP-responsive intracellular vesicles in which AE2/SLC4A2 colocalizes with cell specific Cl- channels (CFTR in cholangiocytes and not yet determined in hepatocytes) and aquaporins (AQP8 in hepatocytes and AQP1 in cholangiocytes). cAMP-induced coordinated trafficking of these vesicles to either canalicular or cholangiocyte lumenal membranes and further exocytosis results in increased osmotic forces and passive movement of water with net bicarbonate-rich hydrocholeresis.
Collapse
Affiliation(s)
- Jesús-M Banales
- Laboratory of Molecular Genetics, Division of Gene Therapy and Hepatology, University of Navarra School of Medicine, Clinica Universitaria and CIMA, Avda. Pio XII 55, E-31008 Pamplona, Spain
| | | | | |
Collapse
|
34
|
Stefan C, Jansen S, Bollen M. Modulation of purinergic signaling by NPP-type ectophosphodiesterases. Purinergic Signal 2006; 2:361-70. [PMID: 18404476 PMCID: PMC2254485 DOI: 10.1007/s11302-005-5303-4] [Citation(s) in RCA: 115] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2005] [Revised: 11/11/2005] [Accepted: 11/11/2005] [Indexed: 12/17/2022] Open
Abstract
Extracellular nucleotides can elicit a wide array of cellular responses by binding to specific purinergic receptors. The level of ectonucleotides is dynamically controlled by their release from cells, synthesis by ectonucleoside diphosphokinases and ectoadenylate kinases, and hydrolysis by ectonucleotidases. One of the four structurally unrelated families of ectonucleotidases is represented by the NPP-type ectophosphodiesterases. Three of the seven members of the NPP family, namely NPP1–3, are known to hydrolyze nucleotides. The enzymatic action of NPP1–3 (in)directly results in the termination of nucleotide signaling, the salvage of nucleotides and/or the generation of new messengers like ADP, adenosine or pyrophosphate. NPP2 is unique in that it hydrolyzes both nucleotides and lysophospholipids and, thereby, generates products that could synergistically promote cell motility. We review here the enzymatic properties of NPPs and analyze current evidence that links their nucleotide-hydrolyzing capability to epithelial and neural functions, the immune response and cell motility.
Collapse
Affiliation(s)
- Cristiana Stefan
- Division of Biochemistry, Department of Molecular Cell Biology, Faculty of Medicine, KULeuven, B-3000, Leuven, Belgium,
| | | | | |
Collapse
|
35
|
Nieuwenhuijs VB, De Bruijn MT, Padbury RTA, Barritt GJ. Hepatic ischemia-reperfusion injury: roles of Ca2+ and other intracellular mediators of impaired bile flow and hepatocyte damage. Dig Dis Sci 2006; 51:1087-102. [PMID: 16865576 DOI: 10.1007/s10620-006-8014-y] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/23/2005] [Accepted: 07/27/2005] [Indexed: 12/16/2022]
Abstract
Liver resection and liver transplantation have been successful in the treatment of liver tumors and end-stage liver disease. This success has led to an expansion in the pool of patients potentially treatable by liver surgery and, in the case of transplantation, to a shortage of liver donors. At present, there are significant numbers of potential candidates for liver resection and liver donation who have fatty livers, are aged, or have livers damaged by chemotherapy. All of these are at high risk for ischemic reperfusion (IR) injury. The aims of this review are to assess current knowledge of the clinical effectiveness of ischemic preconditioning and intermittent ischemia in reducing IR damage in liver surgery; to evaluate the use of bile flow as a sensitive indicator of IR liver damage; and to analyze the molecular mechanisms, especially intracellular Ca2+, involved in IR injury and ischemic preconditioning. It is concluded that bile flow is a sensitive indicator of IR injury. Together with reactive oxygen species (ROS) and other extracellular and intracellular signaling molecules, intracellular Ca2+ in hepatocytes plays a key role in the normal regulation of bile flow and in IR-induced injury and cell death. Ischemic preconditioning is an effective strategy to reduce IR injury but there is considerable scope for improvement, especially in patients with fatty and aged livers. The development of effective new strategies to reduce IR injury will depend on improved understanding of the molecular mechanisms involved, especially by gaining a better perspective of the relative importance of the various intrahepatocyte signaling pathways involved.
Collapse
Affiliation(s)
- Vincent B Nieuwenhuijs
- HPB and Liver Transplant Unit, Flinders Medical Centre and School of Medicine, Flinders University, Bedford Park, South Australia, 5042, Australia
| | | | | | | |
Collapse
|
36
|
Banales JM, Arenas F, Rodríguez-Ortigosa CM, Sáez E, Uriarte I, Doctor RB, Prieto J, Medina JF. Bicarbonate-rich choleresis induced by secretin in normal rat is taurocholate-dependent and involves AE2 anion exchanger. Hepatology 2006; 43:266-75. [PMID: 16440368 DOI: 10.1002/hep.21042] [Citation(s) in RCA: 83] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
Canalicular bile is modified along bile ducts through reabsorptive and secretory processes regulated by nerves, bile salts, and hormones such as secretin. Secretin stimulates ductular cystic fibrosis transmembrane conductance regulator (CFTR)-dependent Cl- efflux and subsequent biliary HCO3- secretion, possibly via Cl-/HCO3- anion exchange (AE). However, the contribution of secretin to bile regulation in the normal rat, the significance of choleretic bile salts in secretin effects, and the role of Cl-/HCO3- exchange in secretin-stimulated HCO3- secretion all remain unclear. Here, secretin was administered to normal rats with maintained bile acid pool via continuous taurocholate infusion. Bile flow and biliary HCO3- and Cl- excretion were monitored following intrabiliary retrograde fluxes of saline solutions with and without the Cl- channel inhibitor 5-nitro-2-(3-phenylpropylamino)-benzoic acid (NPPB) or the Cl-/HCO3- exchange inhibitor 4,4'-diisothiocyanatostilbene-2,2'-disulfonic acid (DIDS). Secretin increased bile flow and biliary excretion of HCO3- and Cl-. Interestingly, secretin effects were not observed in the absence of taurocholate. Whereas secretin effects were all blocked by intrabiliary NPPB, DIDS only inhibited secretin-induced increases in bile flow and HCO3- excretion but not the increased Cl- excretion, revealing a role of biliary Cl-/HCO3- exchange in secretin-induced, bicarbonate-rich choleresis in normal rats. Finally, small hairpin RNA adenoviral constructs were used to demonstrate the involvement of the Na+-independent anion exchanger 2 (AE2) through gene silencing in normal rat cholangiocytes. AE2 gene silencing caused a marked inhibition of unstimulated and secretin-stimulated Cl-/HCO3- exchange. In conclusion, maintenance of the bile acid pool is crucial for secretin to induce bicarbonate-rich choleresis in the normal rat and that this occurs via a chloride-bicarbonate exchange process consistent with AE2 function.
Collapse
Affiliation(s)
- Jesús M Banales
- Laboratory of Molecular Genetics, Division of Gene Therapy and Hepatology, University of Navarra School of Medicine, Clínica Universitaria and CIMA, Pamplona, Spain
| | | | | | | | | | | | | | | |
Collapse
|
37
|
Taffetani S, Ueno Y, Meng F, Venter J, Francis H, Glaser S, Alpini G, Patel T. Tannic acid inhibits cholangiocyte proliferation after bile duct ligation via a cyclic adenosine 5',3'-monophosphate-dependent pathway. THE AMERICAN JOURNAL OF PATHOLOGY 2005; 166:1671-9. [PMID: 15920152 PMCID: PMC1602411 DOI: 10.1016/s0002-9440(10)62477-7] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
Chronic cholestatic diseases are characterized by morphological changes involving cholangiocyte proliferation and functional alterations of secretory capacity. The plant polyphenol tannic acid inhibits the growth of malignant human cholangiocytes. However, the mechanisms by which tannic acid limits excessive cholangiocyte proliferation are unknown. In this study we assessed the effect of tannic acid on cholangiocyte proliferation after bile duct ligation in rats. Tannic acid feeding decreased cholangiocyte proliferation and ductal mass in vivo after bile duct ligation. These changes were associated with functional changes in bile secretion and with decreases of intracellular cyclic adenosine 5',3'-monophosphate. The anti-proliferative effect of tannic acid was associated with a reduction of ERK1,2 phosphorylation. Additionally, tannic acid feeding decreased protein kinase A phosphorylation and activity. Similar changes were observed in isolated cholangiocytes during in vitro incubation with tannic acid. Furthermore, forskolin abolished the anti-proliferative effect of tannic acid on cholangiocyte proliferation after bile duct ligation. In conclusion, the anti-proliferative effects of tannic acid in cholangiocytes involve modulation of ERK1,2 by a cyclic adenosine 5',3'-monophosphate-protein kinase A-dependent pathway. These data suggest that tannic acid may be useful in limiting excessive cholangiocyte proliferation and modulating secretion during cholestasis.
Collapse
Affiliation(s)
- Silvia Taffetani
- Department of Internal Medicine, Texas A&M University System Health Science Center College of Medicine, Temple, Texas, USA
| | | | | | | | | | | | | | | |
Collapse
|
38
|
Beaussier M, Wendum D, Fouassier L, Rey C, Barbu V, Lasnier E, Lienhart A, Scoazec JY, Rosmorduc O, Housset C. Adaptative bile duct proliferative response in experimental bile duct ischemia. J Hepatol 2005; 42:257-65. [PMID: 15664253 DOI: 10.1016/j.jhep.2004.10.025] [Citation(s) in RCA: 49] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/25/2004] [Revised: 10/18/2004] [Accepted: 10/26/2004] [Indexed: 12/30/2022]
Abstract
BACKGROUND/AIMS A rat model of bile duct ischemia was established and used to examine the potential of bile duct proliferation to provide an adaptative response in cholestatic disorders. METHODS Rats underwent partial or complete arterial deprivation of the liver. Serum biochemical tests, histological analyses and bile secretion measurements were performed at different time points up to 6 weeks after surgery. RESULTS Rats developed biochemical signs of cholestasis exclusively after complete arterial deprivation. Within 4h, cholangiocytes in these rats showed morphological signs of cell damage. After 48h, they displayed VEGF expression and became proliferative. The proportion of Ki67-labeled cholangiocytes ( approximately 30%) was similar in interlobular bile ducts and periportal ductules. A ductular reaction made of well-formed bile ducts confined to portal tracts developed within 1 week. Bile flow which was initially decreased, was restored at 3 weeks, while the biochemical signs of cholestasis completely resolved at 6 weeks. At this time, the number of bile duct sections was maximal. Fibrosis intensity was also maximal, although moderate (<F2 METAVIR staging) as assessed by Sirius-red staining morphometry. CONCLUSIONS In the present model of bile duct ischemia, ductular reaction derives from bile ducts of all anatomical compartments, and provides a poorly fibrogenic functional response to biliary dysfunction.
Collapse
Affiliation(s)
- Marc Beaussier
- INSERM U402, Faculté de Médecine Saint-Antoine, Université Pierre et Marie Curie, 27 rue Chaligny, 75571 Paris Cedex 12, France
| | | | | | | | | | | | | | | | | | | |
Collapse
|
39
|
Ruiz ML, Villanueva SSM, Luquita MG, Sánchez-Pozzi EJ, Crocenzi FA, Pellegrino JM, Ochoa JE, Vore M, Mottino AD, Catania VA. Mechanisms involved in spironolactone-induced choleresis in the rat. Biochem Pharmacol 2005; 69:531-9. [PMID: 15652244 DOI: 10.1016/j.bcp.2004.10.017] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2004] [Accepted: 10/27/2004] [Indexed: 11/21/2022]
Abstract
The mechanisms involved in spironolactone (SL, 200 micromol/kg body weight, 3 days i.p.)-induced choleresis were explored in vivo by evaluating bile salt export pump (Bsep)-, multidrug resistance-associated protein 2 (Mrp2)-, and anion exchanger 2 (AE2)-mediated secretory processes in rat liver. Hepatic bile salt metabolism was also analyzed. Total bile flow was significantly increased by SL, primarily due to an increase in bile salt-independent bile flow, whereas bile salt secretion was decreased. SL did not produce any choleresis in TR(-) rats. SL decreased the de novo bile salt synthesis rate in concordance with impaired microsomal cholesterol 7 alpha-hydroxylase activity, thus leading to a decrease in endogenous bile salt pool size. In contrast, the maximum secretory rate of tauroursodeoxycholate as well as expression of Bsep protein detected by Western blotting were not affected. Thus, decreased bile salt availability for canalicular transport rather than transport capability itself likely explains reduced biliary secretion of bile salts. Biliary secretion of glutathione, an endogenous substrate of Mrp2, and HCO(3)(-), the AE2 substrate, were increased by SL, as a main factor explaining enhanced bile salt-independent bile flow. Western blot studies revealed increased expression of Mrp2 in response to SL whereas AE2 content remained unchanged. Enhanced activity and expression of Mrp2 was confirmed by analyzing the excretion rate of dinitrophenyl S-glutathione, an exogenous substrate of Mrp2, in isolated hepatocytes and by immunofluorescence microscopy, respectively. We conclude that SL increased bile flow mainly by increasing the biliary secretion of glutathione species and HCO(3)(-); increased expression of Mrp2 is also involved.
Collapse
Affiliation(s)
- María L Ruiz
- Instituto de Fisiología Experimental (CONICET), Facultad de Ciencias, Bioquímicas y Farmacéutica (UNR), Suipacha 570, Rosario 2000, Argentina
| | | | | | | | | | | | | | | | | | | |
Collapse
|
40
|
Pusl T, Nathanson MH. The role of inositol 1,4,5-trisphosphate receptors in the regulation of bile secretion in health and disease. Biochem Biophys Res Commun 2004; 322:1318-25. [PMID: 15336978 DOI: 10.1016/j.bbrc.2004.08.036] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2004] [Indexed: 01/05/2023]
Abstract
Ca2+ signaling via the inositol 1,4,5-trisphosphate receptor (InsP3R) is a ubiquitous mechanism for regulation of cell function, yet very little is known about the role of the InsP3R in specific disease states. Converging lines of evidence suggest that the liver may provide a model for the role of the InsP3R in health and disease. Ca2+ signaling is mediated entirely by the InsP3R in hepatocytes and cholangiocytes, the two types of epithelia in the liver. Here we review the role of specific InsP3R isoforms and the physiological effects of InsP3R-mediated Ca2+ signals in both of these types of epithelia. In addition, we review evidence that the InsP3R is lost from cholangiocytes in cholestatic forms of liver disease, and discuss this as a possible final common pathway for cholestasis.
Collapse
Affiliation(s)
- Thomas Pusl
- Department of Medicine II, Klinikum of the University of Munich-Grosshadern, 81377 Munich, Germany
| | | |
Collapse
|
41
|
Portincasa P, Moschetta A, Mazzone A, Palasciano G, Svelto M, Calamita G. Water handling and aquaporins in bile formation: recent advances and research trends. J Hepatol 2003; 39:864-74. [PMID: 14568273 DOI: 10.1016/s0168-8278(03)00294-0] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Affiliation(s)
- Piero Portincasa
- Section of Internal Medicine, Department of Internal Medicine and Public Medicine, Medical School, University of Bari, Bari, Italy
| | | | | | | | | | | |
Collapse
|
42
|
Shibao K, Hirata K, Robert ME, Nathanson MH. Loss of inositol 1,4,5-trisphosphate receptors from bile duct epithelia is a common event in cholestasis. Gastroenterology 2003; 125:1175-87. [PMID: 14517800 PMCID: PMC2831084 DOI: 10.1016/s0016-5085(03)01201-0] [Citation(s) in RCA: 95] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
BACKGROUND AND AIMS Cholestasis is one of the principal manifestations of liver disease and often results from disorders involving bile duct epithelia rather than hepatocytes. A range of disorders affects biliary epithelia, and no unifying pathophysiologic event in these cells has been identified as the cause of cholestasis. Here we examined the role of the inositol 1,4,5-trisphosphate receptor (InsP3R)/Ca(2+) release channel in Ca(2+) signaling and ductular secretion in animal models of cholestasis and in patients with cholestatic disorders. METHODS The expression and distribution of the InsP3R and related proteins were examined in rat cholangiocytes before and after bile duct ligation or treatment with endotoxin. Ca(2+) signaling was examined in isolated bile ducts from these animals, whereas ductular bicarbonate secretion was examined in isolated perfused livers. Confocal immunofluorescence was used to examine cholangiocyte InsP3R expression in human liver biopsy specimens. RESULTS Expression of the InsP3R was selectively lost from biliary epithelia after bile duct ligation or endotoxin treatment. As a result, Ca(2+) signaling and Ca(2+)-mediated bicarbonate secretion were lost as well, although other components of the Ca(2+) signaling pathway and adenosine 3',5'-cyclic monophosphate (cAMP)-mediated bicarbonate secretion both were preserved. Examination of human liver biopsy specimens showed that InsP3Rs also were lost from bile duct epithelia in a range of human cholestatic disorders, although InsP3R expression was intact in noncholestatic liver disease. CONCLUSIONS InsP3-mediated Ca(2+) signaling in bile duct epithelia appears to be important for normal bile secretion in the liver, and loss of InsP3Rs may be a final common pathway for cholestasis.
Collapse
Affiliation(s)
- Kazunori Shibao
- Department of Internal Medicine, Yale University School of Medicine, New Haven, Connecticut 06520-8019, USA
| | | | | | | |
Collapse
|
43
|
Alpini G, Ueno Y, Tadlock L, Glaser SS, LeSage G, Francis H, Taffetani S, Marzioni M, Alvaro D, Patel T. Increased susceptibility of cholangiocytes to tumor necrosis factor-alpha cytotoxicity after bile duct ligation. Am J Physiol Cell Physiol 2003; 285:C183-94. [PMID: 12637265 DOI: 10.1152/ajpcell.00497.2002] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
Abstract
Tumor necrosis factor (TNF)-alpha plays a critical role in epithelial cell injury. However, the role of TNF-alpha in mediating cholangiocyte injury under physiological or pathophysiological conditions is unknown. Thus we assessed the effects of TNF-alpha alone or following sensitization by actinomycin D on cell apoptosis, proliferation, and basal and secretin-stimulated ductal secretion in cholangiocytes from normal or bile duct-ligated (BDL) rats. Cholangiocytes from normal or BDL rats were highly resistant to TNF-alpha alone. However, presensitization by actinomycin D increased apoptosis in cholangiocytes following BDL and was associated with an inhibition of proliferation and secretin-stimulated ductal secretion. Thus TNF-alpha mediates cholangiocyte injury and altered ductal secretion following bile duct ligation. These observations suggest that cholestasis may enhance susceptibility to cytokine-mediated cholangiocyte injury.
Collapse
Affiliation(s)
- Gianfranco Alpini
- Department of Internal Medicine, Texas A&M University System Health Science Center, College of Medicine, Temple, TX 76502, USA
| | | | | | | | | | | | | | | | | | | |
Collapse
|
44
|
Glaser S, Alvaro D, Roskams T, Phinizy JL, Stoica G, Francis H, Ueno Y, Barbaro B, Marzioni M, Mauldin J, Rashid S, Mancino MG, LeSage G, Alpini G. Dopaminergic inhibition of secretin-stimulated choleresis by increased PKC-gamma expression and decrease of PKA activity. Am J Physiol Gastrointest Liver Physiol 2003; 284:G683-94. [PMID: 12505882 DOI: 10.1152/ajpgi.00302.2002] [Citation(s) in RCA: 56] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
To determine the role and mechanisms of action by which dopaminergic innervation modulates ductal secretion in bile duct-ligated rats, we determined the expression of D1, D2, and D3 dopaminergic receptors in cholangiocytes. We evaluated whether D1, D2 (quinelorane), or D3 dopaminergic receptor agonists influence basal and secretin-stimulated choleresis and lumen expansion in intrahepatic bile duct units (IBDU) and cAMP levels in cholangiocytes in the absence or presence of BAPTA-AM, chelerythrine, 1-(5-isoquinolinylsulfonyl)-2-methyl piperazine (H7), or rottlerin. We evaluated whether 1) quinelorane effects on ductal secretion were associated with increased expression of Ca(2+)-dependent PKC isoforms and 2) increased expression of PKC causes inhibition of PKA activity. Quinelorane inhibited secretin-stimulated choleresis in vivo and IBDU lumen space, cAMP levels, and PKA activity in cholangiocytes. The inhibitory effects of quinelorane on secretin-stimulated ductal secretion and PKA activity were blocked by BAPTA-AM, chelerythrine, and H7. Quinelorane effects on ductal secretion were associated with activation of the Ca(2+)-dependent PKC-gamma but not other PKC isoforms. The dopaminergic nervous system counterregulates secretin-stimulated ductal secretion in experimental cholestasis.
Collapse
Affiliation(s)
- Shannon Glaser
- Department of Internal Medicine, Texas A&M University System Health Sciences Center, College of Medicine, Temple, Texas 76504, USA
| | | | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
45
|
Bode HP, Wang L, Cassio D, Leite MF, St-Pierre MV, Hirata K, Okazaki K, Sears ML, Meda P, Nathanson MH, Dufour JF. Expression and regulation of gap junctions in rat cholangiocytes. Hepatology 2002; 36:631-40. [PMID: 12198655 DOI: 10.1053/jhep.2002.35274] [Citation(s) in RCA: 60] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
Hepatocytes and other digestive epithelia exchange second messengers and coordinate their functions by communicating through gap junctions. However, little is known about intercellular communication in cholangiocytes. The aim of this study was to examine expression and regulation of gap junctions in cholangiocytes. Connexin expression was determined by confocal immunofluorescence in rat bile ducts and in normal rat cholangiocyte (NRC) cells, a polarized cholangiocyte cell line. Intercellular Ca(2+) signaling was monitored by fluorescent microscopy. Microinjection studies assessed regulation of gap junction permeability in NRC cells and in SKHep1 cells, a liver-derived cell line engineered to express connexin 43. Immunochemistry showed that cholangiocytes from normal rat liver as well as the NRC cells express connexin 43. Localization of apical, basolateral, and tight junction proteins confirmed that NRC cells are well polarized. Apical exposure to ATP induced Ca(2+) oscillations that were coordinated among neighboring NRC cells, and inhibition of gap junction conductance desynchronized the Ca(2+) oscillations. NRC cells transfected with a connexin 43 antisense were significantly less coupled. Transcellular dye spreading was inhibited by activation of protein kinase A or protein kinase C. The same was observed in transfected SKHep1 cells, which expressed only connexin 43. Rat cholangiocytes and NRC cells express connexin 43, which permits synchronization of Ca(2+) signals among cells. Permeability of connexin 43-gap junctions is negatively regulated by protein kinases A and C. In conclusion, cholangiocytes have the capacity for intercellular communication of second messenger signals via gap junctions in a fashion that is under hormonal control.
Collapse
Affiliation(s)
- Hans-Peter Bode
- Department of Gastroenterology, University of Bern, Bern, Switzerland
| | | | | | | | | | | | | | | | | | | | | |
Collapse
|
46
|
Hirata K, Dufour JF, Shibao K, Knickelbein R, O'Neill AF, Bode HP, Cassio D, St-Pierre MV, LaRusso NF, Leite MF, Nathanson MH. Regulation of Ca(2+) signaling in rat bile duct epithelia by inositol 1,4,5-trisphosphate receptor isoforms. Hepatology 2002; 36:284-96. [PMID: 12143036 PMCID: PMC2987686 DOI: 10.1053/jhep.2002.34432] [Citation(s) in RCA: 70] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
Cytosolic Ca(2+) (Ca(i)(2+)) regulates secretion of bicarbonate and other ions in the cholangiocyte. In other cell types, this second messenger acts through Ca(2+) waves, Ca(2+) oscillations, and other subcellular Ca(2+) signaling patterns, but little is known about the subcellular organization of Ca(2+) signaling in cholangiocytes. Therefore, we examined Ca(2+) signaling and the subcellular distribution of Ca(2+) release channels in cholangiocytes and in a model cholangiocyte cell line. The expression and subcellular distribution of inositol 1,4,5-trisphosphate (InsP(3)) receptor (InsP(3)R) isoforms and the ryanodine receptor (RyR) were determined in cholangiocytes from normal rat liver and in the normal rat cholangiocyte (NRC) polarized bile duct cell line. Subcellular Ca(2+) signaling in cholangiocytes was examined by confocal microscopy. All 3 InsP(3)R isoforms were expressed in cholangiocytes, whereas RyR was not expressed. The type III InsP(3)R was the most heavily expressed isoform at the protein level and was concentrated apically, whereas the type I and type II isoforms were expressed more uniformly. The type III InsP(3)R was expressed even more heavily in NRC cells but was concentrated apically in these cells as well. Adenosine triphosphate (ATP), which increases Ca(2+) via InsP(3) in cholangiocytes, induced Ca(2+) oscillations in both cholangiocytes and NRC cells. Acetylcholine (ACh) induced apical-to-basal Ca(2+) waves. In conclusion, Ca(2+) signaling in cholangiocytes occurs as polarized Ca(2+) waves that begin in the region of the type III InsP(3)R. Differential subcellular localization of InsP(3)R isoforms may be an important molecular mechanism for the formation of Ca(2+) waves and oscillations in cholangiocytes. Because Ca(i)(2+) is in part responsible for regulating ductular secretion, these findings also may have implications for the molecular basis of cholestatic disorders.
Collapse
Affiliation(s)
- Keiji Hirata
- Department of Internal Medicine, Yale University School of Medicine, New Haven, CT
| | | | - Kazunori Shibao
- Department of Internal Medicine, Yale University School of Medicine, New Haven, CT
| | - Roy Knickelbein
- Department of Internal Medicine, Yale University School of Medicine, New Haven, CT
| | - Allison F. O'Neill
- Department of Internal Medicine, Yale University School of Medicine, New Haven, CT
| | - Hans-Peter Bode
- Department of Gastroenterology, University of Bern, Bern, Switzerland
| | | | - Marie V. St-Pierre
- Department of Clinical Pharmacology, University of Zürich, Zürich, Switzerland
| | | | - M. Fatima Leite
- Department of Physiology and Biophysics, UFMG, Belo Horizonte, Brazil
| | - Michael H. Nathanson
- Department of Internal Medicine, Yale University School of Medicine, New Haven, CT
| |
Collapse
|
47
|
Abstract
Due in part to the recent development of new experimental models, cholangiocytes--the epithelial cells that line the bile ducts--are increasingly recognized as important transporting epithelia actively involved in the absorption and secretion of water, ions, and solutes. New biologic concepts have emerged including the identification and topography of receptors and flux proteins involved in the molecular mechanisms of ductal bile secretion. Individually isolated or perfused bile duct units from livers of rats and mice serve as new, physiologically relevant in vitro models to study cholangiocyte transport. Biliary tree dimensions and novel insights into anatomic remodeling of proliferating bile ducts have emerged from three-dimensional reconstruction using computed tomographic scanning and sophisticated software. Moreover, new pathologic concepts have arisen regarding the interaction of cholangiocytes with pathogens. These concepts may provide the framework for new therapies for the cholangiopathies, a group of important hepatobiliary diseases in which cholangiocytes are the target cell.
Collapse
Affiliation(s)
- Pamela Tietz
- Division of Gastroenterology and Hepatology, Department of Internal Medicine, Mayo Clinic, Medical School, Rochester, Minnesota 55905, USA
| | | |
Collapse
|