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Javitt NB. Hepatic Bile Formation: Developing a New Paradigm. Pharmacol Rev 2023; 75:1036-1042. [PMID: 37532432 DOI: 10.1124/pharmrev.122.000799] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2022] [Revised: 03/07/2023] [Accepted: 04/20/2023] [Indexed: 08/04/2023] Open
Abstract
In 1959, Ivar Sperber contrasted bile formation with that of urine and proposed that water flow into the canalicular conduit is in response to an osmotic, not a hydrostatic, gradient. Early attempts to support the hypothesis using a bile acid, sodium taurocholate, and the hormone secretin to stimulate bile flow led to conflicting data and a moratorium on attempts to further develop the initial proposal. However, current data amplify the initial proposal and indicate both paracellular and transcellular water flow into hepatic ductules and the canalicular conduit in response to an osmotic gradient. Also, the need to further modify the initial proposal became apparent with the recognition that bile acid aggregates (micelles), which form in the canalicular conduit, generate lecithin-cholesterol vesicles that contain water unrelated to an osmotic gradient. As part of this development is the recent introduction of the fluorescent localization after photobleaching technique for direct determination of hepatic duct flow and clarification of the role of biomarkers such as mannitol and polyethylene glycol 900. With the new paradigm, these biomarkers may prove useful for quantifying paracellular and transcellular water flow, respectively. SIGNIFICANCE STATEMENT: It is essential to identify and characterize all the sites for water flow during hepatic bile formation to obtain more precision in evaluating the causes and possible therapeutic approaches to cholestatic syndromes. Updating the Sperber proposal provides a new paradigm that addresses the advances in knowledge that have occurred.
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Affiliation(s)
- Norman B Javitt
- NYU Grossman School of Medicine, Division of Gastroenterology and Hepatology, New York, New York
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2
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Pryymachuk G, El-Awaad E, Piekarek N, Drebber U, Maul AC, Hescheler J, Wodarz A, Pfitzer G, Neiss WF, Pietsch M, Schroeter MM. Angiotensin II type 1 receptor localizes at the blood-bile barrier in humans and pigs. Histochem Cell Biol 2022; 157:513-524. [PMID: 35229169 PMCID: PMC9114028 DOI: 10.1007/s00418-022-02087-z] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 02/07/2022] [Indexed: 12/24/2022]
Abstract
Animal models and clinical studies suggest an influence of angiotensin II (AngII) on the pathogenesis of liver diseases via the renin–angiotensin system. AngII application increases portal blood pressure, reduces bile flow, and increases permeability of liver tight junctions. Establishing the subcellular localization of angiotensin II receptor type 1 (AT1R), the main AngII receptor, helps to understand the effects of AngII on the liver. We localized AT1R in situ in human and porcine liver and porcine gallbladder by immunohistochemistry. In order to do so, we characterized commercial anti-AT1R antibodies regarding their capability to recognize heterologous human AT1R in immunocytochemistry and on western blots, and to detect AT1R using overlap studies and AT1R-specific blocking peptides. In hepatocytes and canals of Hering, AT1R displayed a tram-track-like distribution, while in cholangiocytes AT1R appeared in a honeycomb-like pattern; i.e., in liver epithelia, AT1R showed an equivalent distribution to that in the apical junctional network, which seals bile canaliculi and bile ducts along the blood–bile barrier. In intrahepatic blood vessels, AT1R was most prominent in the tunica media. We confirmed AT1R localization in situ to the plasma membrane domain, particularly between tight and adherens junctions in both human and porcine hepatocytes, cholangiocytes, and gallbladder epithelial cells using different anti-AT1R antibodies. Localization of AT1R at the junctional complex could explain previously reported AngII effects and predestines AT1R as a transmitter of tight junction permeability.
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Affiliation(s)
- Galyna Pryymachuk
- Department of Anatomy I, University of Cologne, Faculty of Medicine and University Hospital Cologne, Kerpener Str. 62, 50937, Cologne, Germany.
| | - Ehab El-Awaad
- Institute II of Pharmacology, Center of Pharmacology, University of Cologne, Faculty of Medicine and University Hospital Cologne, Gleueler Str. 24, 50931, Cologne, Germany
- Department of Pharmacology, Faculty of Medicine, Assiut University, Assiut, 71515, Egypt
| | - Nadin Piekarek
- Department of Anatomy I, University of Cologne, Faculty of Medicine and University Hospital Cologne, Kerpener Str. 62, 50937, Cologne, Germany
| | - Uta Drebber
- Institute of Pathology, University of Cologne, Faculty of Medicine and University Hospital Cologne, Kerpener Str. 62, 50937, Cologne, Germany
| | - Alexandra C Maul
- Experimental Medicine, University of Cologne, Faculty of Medicine and University Hospital Cologne, Ostmerheimer Str. 200, 51109, Cologne, Germany
| | - Juergen Hescheler
- Institute for Neurophysiology, Center for Physiology and Pathophysiology, University of Cologne, Faculty of Medicine and University Hospital Cologne, Robert-Koch-Str. 39, 50931, Cologne, Germany
| | - Andreas Wodarz
- Department of Anatomy I, University of Cologne, Faculty of Medicine and University Hospital Cologne, Kerpener Str. 62, 50937, Cologne, Germany
- Cologne Excellence Cluster Cellular Stress Response in Aging-Associated Diseases (CECAD), University of Cologne, Joseph-Stelzmann-Str. 26, 50931, Cologne, Germany
- Center for Molecular Medicine Cologne, University of Cologne, Robert-Koch-Str. 21, 50931, Cologne, Germany
| | - Gabriele Pfitzer
- Institute of Vegetative Physiology, Center for Physiology and Pathophysiology, University of Cologne, Faculty of Medicine and University Hospital Cologne, Robert-Koch-Str. 39, 50931, Cologne, Germany
| | - Wolfram F Neiss
- Department of Anatomy I, University of Cologne, Faculty of Medicine and University Hospital Cologne, Kerpener Str. 62, 50937, Cologne, Germany
| | - Markus Pietsch
- Institute II of Pharmacology, Center of Pharmacology, University of Cologne, Faculty of Medicine and University Hospital Cologne, Gleueler Str. 24, 50931, Cologne, Germany
| | - Mechthild M Schroeter
- Institute for Neurophysiology, Center for Physiology and Pathophysiology, University of Cologne, Faculty of Medicine and University Hospital Cologne, Robert-Koch-Str. 39, 50931, Cologne, Germany
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3
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Vartak N, Hengstler JG. Reply. Hepatology 2022; 75:493-494. [PMID: 34546585 DOI: 10.1002/hep.32168] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/10/2021] [Accepted: 09/15/2021] [Indexed: 12/08/2022]
Affiliation(s)
- Nachiket Vartak
- Leibniz Institute for Working Environment and Human Factors (IfADo)DortmundGermany
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Javitt NB. Hepatic bile formation: bile acid transport and water flow into the canalicular conduit. Am J Physiol Gastrointest Liver Physiol 2020; 319:G609-G618. [PMID: 32935994 DOI: 10.1152/ajpgi.00078.2020] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
Advances in molecular biology identifying the many carrier-mediated organic anion transporters and advances in microscopy that have provided a more detailed anatomy of the canalicular conduit make updating the concept of osmotically determined canalicular flow possible. For the most part water flow is not transmembrane but via specific pore proteins in both the hepatocyte and the tight junction. These pores independently regulate the rate at which water flows in response to an osmotic gradient and therefore are determinants of canalicular bile acid concentration. Review of the literature indicates that the initial effect on hepatic bile flow of cholestatic agents such as Thorazine and estradiol 17β-glucuronide are on water flow and not bile salt export pump-mediated bile acid transport and thus provides new approaches to the pathogenesis of drug-induced liver injury. Attaining a micellar concentration of bile acids in the canaliculus is essential to the formation of cholesterol-lecithin vesicles, which mostly occur in the periportal region of the canalicular conduit. The other regions, midcentral and pericentral, may transport lesser amounts of bile acid but augment water flow. Broadening the concept of how hepatic bile flow is initiated, provides new insights into the pathogenesis of canalicular cholestasis.
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Affiliation(s)
- Norman B Javitt
- Division of Gastroenterology and Hepatology, New York University Grossman School of Medicine, New York, New York
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Schulze RJ, Schott MB, Casey CA, Tuma PL, McNiven MA. The cell biology of the hepatocyte: A membrane trafficking machine. J Cell Biol 2019; 218:2096-2112. [PMID: 31201265 PMCID: PMC6605791 DOI: 10.1083/jcb.201903090] [Citation(s) in RCA: 90] [Impact Index Per Article: 18.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2019] [Revised: 05/24/2019] [Accepted: 05/28/2019] [Indexed: 12/24/2022] Open
Abstract
The liver performs numerous vital functions, including the detoxification of blood before access to the brain while simultaneously secreting and internalizing scores of proteins and lipids to maintain appropriate blood chemistry. Furthermore, the liver also synthesizes and secretes bile to enable the digestion of food. These diverse attributes are all performed by hepatocytes, the parenchymal cells of the liver. As predicted, these cells possess a remarkably well-developed and complex membrane trafficking machinery that is dedicated to moving specific cargos to their correct cellular locations. Importantly, while most epithelial cells secrete nascent proteins directionally toward a single lumen, the hepatocyte secretes both proteins and bile concomitantly at its basolateral and apical domains, respectively. In this Beyond the Cell review, we will detail these central features of the hepatocyte and highlight how membrane transport processes play a key role in healthy liver function and how they are affected by disease.
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Affiliation(s)
- Ryan J Schulze
- Division of Gastroenterology and Hepatology, Department of Biochemistry and Molecular Biology, Mayo Clinic, Rochester, MN
| | - Micah B Schott
- Division of Gastroenterology and Hepatology, Department of Biochemistry and Molecular Biology, Mayo Clinic, Rochester, MN
| | - Carol A Casey
- Research Service, Department of Veterans Affairs, Nebraska-Western Iowa Health Care System, Omaha, NE
- Departments of Internal Medicine and Biochemistry & Molecular Biology, University of Nebraska Medical Center, Omaha, NE
| | | | - Mark A McNiven
- Division of Gastroenterology and Hepatology, Department of Biochemistry and Molecular Biology, Mayo Clinic, Rochester, MN
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Gupta K, Li Q, Fan JJ, Fong ELS, Song Z, Mo S, Tang H, Ng IC, Ng CW, Pawijit P, Zhuo S, Dong CY, Low BC, Wee A, Dan YY, Kanchanawong P, So P, Viasnoff V, Yu H. Actomyosin contractility drives bile regurgitation as an early response during obstructive cholestasis. J Hepatol 2017; 66:1231-1240. [PMID: 28189756 DOI: 10.1016/j.jhep.2017.01.026] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/29/2016] [Revised: 01/10/2017] [Accepted: 01/29/2017] [Indexed: 01/06/2023]
Abstract
BACKGROUND & AIMS A wide range of liver diseases manifest as biliary obstruction, or cholestasis. However, the sequence of molecular events triggered as part of the early hepatocellular homeostatic response in obstructive cholestasis is poorly elucidated. Pericanalicular actin is known to accumulate during obstructive cholestasis. Therefore, we hypothesized that the pericanalicular actin cortex undergoes significant remodeling as a regulatory response to obstructive cholestasis. METHODS In vivo investigations were performed in a bile duct-ligated mouse model. Actomyosin contractility was assessed using sandwich-cultured rat hepatocytes transfected with various fluorescently labeled proteins and pharmacological inhibitors of actomyosin contractility. RESULTS Actomyosin contractility induces transient deformations along the canalicular membrane, a process we have termed inward blebbing. We show that these membrane intrusions are initiated by local ruptures in the pericanalicular actin cortex; and they typically retract following repair by actin polymerization and actomyosin contraction. However, above a certain osmotic pressure threshold, these inward blebs pinch away from the canalicular membrane into the hepatocyte cytoplasm as large vesicles (2-8μm). Importantly, we show that these vesicles aid in the regurgitation of bile from the bile canaliculi. CONCLUSION Actomyosin contractility induces the formation of bile-regurgitative vesicles, thus serving as an early homeostatic mechanism against increased biliary pressure during cholestasis. LAY SUMMARY Bile canaliculi expand and contract in response to the amount of secreted bile, and resistance from the surrounding actin bundles. Further expansion due to bile duct blockade leads to the formation of inward blebs, which carry away excess bile to prevent bile build up in the canaliculi.
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Affiliation(s)
- Kapish Gupta
- Mechanobiology Institute, National University of Singapore, Singapore
| | - Qiushi Li
- Mechanobiology Institute, National University of Singapore, Singapore; National University of Singapore Research Institute, Singapore
| | - Jun Jun Fan
- Institute of Bioengineering and Nanotechnology, Agency for Science, Technology and Research (A*STAR), Singapore; BioSyM, Singapore-MIT Alliance for Research and Technology, Singapore; Department of Orthopaedics, Xijing Hospital, Fourth Military Medical University, China
| | - Eliza Li Shan Fong
- Department of Physiology, National University of Singapore, Singapore; Department of Biomedical Engineering, National University of Singapore, Singapore
| | - Ziwei Song
- Institute of Bioengineering and Nanotechnology, Agency for Science, Technology and Research (A*STAR), Singapore
| | - Shupei Mo
- Institute of Bioengineering and Nanotechnology, Agency for Science, Technology and Research (A*STAR), Singapore
| | - Haoyu Tang
- Mechanobiology Institute, National University of Singapore, Singapore
| | - Inn Chuan Ng
- Department of Physiology, National University of Singapore, Singapore
| | - Chan Way Ng
- Department of Physiology, National University of Singapore, Singapore
| | - Pornteera Pawijit
- Department of Physiology, National University of Singapore, Singapore; NUS Graduate School of Integrative Sciences and Engineering, National University of Singapore, Singapore
| | - Shuangmu Zhuo
- BioSyM, Singapore-MIT Alliance for Research and Technology, Singapore; Fujian Normal University, Fuzhou, Fujian, China
| | - Chen-Yuan Dong
- Department of Physics, National Taiwan University, Taiwan
| | - Boon Chuan Low
- Mechanobiology Institute, National University of Singapore, Singapore; Department of Biological Sciences, National University of Singapore, Singapore
| | - Aileen Wee
- Department of Pathology, National University of Singapore, Singapore
| | - Yock Young Dan
- Division of Gastroenterology and Hepatology, National University Hospital, Singapore
| | - Pakorn Kanchanawong
- Mechanobiology Institute, National University of Singapore, Singapore; Department of Biomedical Engineering, National University of Singapore, Singapore
| | - Peter So
- BioSyM, Singapore-MIT Alliance for Research and Technology, Singapore
| | - Virgile Viasnoff
- Mechanobiology Institute, National University of Singapore, Singapore; CNRS UMI3639, Singapore
| | - Hanry Yu
- Mechanobiology Institute, National University of Singapore, Singapore; Institute of Bioengineering and Nanotechnology, Agency for Science, Technology and Research (A*STAR), Singapore; BioSyM, Singapore-MIT Alliance for Research and Technology, Singapore; Department of Physiology, National University of Singapore, Singapore; Department of Gastroenterology, Nanfang Hospital, Southern Medical University, Guangzhou, China.
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7
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Meyer K, Ostrenko O, Bourantas G, Morales-Navarrete H, Porat-Shliom N, Segovia-Miranda F, Nonaka H, Ghaemi A, Verbavatz JM, Brusch L, Sbalzarini I, Kalaidzidis Y, Weigert R, Zerial M. A Predictive 3D Multi-Scale Model of Biliary Fluid Dynamics in the Liver Lobule. Cell Syst 2017; 4:277-290.e9. [PMID: 28330614 DOI: 10.1016/j.cels.2017.02.008] [Citation(s) in RCA: 56] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2016] [Revised: 11/22/2016] [Accepted: 02/08/2017] [Indexed: 01/15/2023]
Abstract
Bile, the central metabolic product of the liver, is transported by the bile canaliculi network. The impairment of bile flow in cholestatic liver diseases has urged a demand for insights into its regulation. Here, we developed a predictive 3D multi-scale model that simulates fluid dynamic properties successively from the subcellular to the tissue level. The model integrates the structure of the bile canalicular network in the mouse liver lobule, as determined by high-resolution confocal and serial block-face scanning electron microscopy, with measurements of bile transport by intravital microscopy. The combined experiment-theory approach revealed spatial heterogeneities of biliary geometry and hepatocyte transport activity. Based on this, our model predicts gradients of bile velocity and pressure in the liver lobule. Validation of the model predictions by pharmacological inhibition of Rho kinase demonstrated a requirement of canaliculi contractility for bile flow in vivo. Our model can be applied to functionally characterize liver diseases and quantitatively estimate biliary transport upon drug-induced liver injury.
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Affiliation(s)
- Kirstin Meyer
- Max Planck Institute of Molecular Cell Biology and Genetics, Dresden, Saxony 01307, Germany
| | - Oleksandr Ostrenko
- Center for Information Services and High Performance Computing, Technische Universität Dresden, Dresden, Saxony 01062, Germany; Center for Advancing Electronics Dresden, Technische Universität Dresden, Dresden, Saxony 01062, Germany
| | - Georgios Bourantas
- Max Planck Institute of Molecular Cell Biology and Genetics, Dresden, Saxony 01307, Germany; Faculty of Science, Technology and Communication, University of Luxembourg, 1359 Luxembourg, Luxembourg; Center for Advancing Electronics Dresden, Technische Universität Dresden, Dresden, Saxony 01062, Germany
| | | | - Natalie Porat-Shliom
- Intracellular Membrane Trafficking Unit, National Institute of Dental and Craniofacial Research, National Institutes of Health, Bethesda, MD 20892, USA
| | - Fabian Segovia-Miranda
- Max Planck Institute of Molecular Cell Biology and Genetics, Dresden, Saxony 01307, Germany
| | - Hidenori Nonaka
- Max Planck Institute of Molecular Cell Biology and Genetics, Dresden, Saxony 01307, Germany
| | - Ali Ghaemi
- Max Planck Institute of Molecular Cell Biology and Genetics, Dresden, Saxony 01307, Germany
| | - Jean-Marc Verbavatz
- Max Planck Institute of Molecular Cell Biology and Genetics, Dresden, Saxony 01307, Germany
| | - Lutz Brusch
- Center for Information Services and High Performance Computing, Technische Universität Dresden, Dresden, Saxony 01062, Germany; Center for Advancing Electronics Dresden, Technische Universität Dresden, Dresden, Saxony 01062, Germany
| | - Ivo Sbalzarini
- Max Planck Institute of Molecular Cell Biology and Genetics, Dresden, Saxony 01307, Germany; Faculty of Computer Science, Technische Universität Dresden, Dresden, Saxony 01187, Germany; Center for Advancing Electronics Dresden, Technische Universität Dresden, Dresden, Saxony 01062, Germany
| | - Yannis Kalaidzidis
- Max Planck Institute of Molecular Cell Biology and Genetics, Dresden, Saxony 01307, Germany; Faculty of Bioengineering and Bioinformatics, Moscow State University, 119991 Moscow, Russia
| | - Roberto Weigert
- Intracellular Membrane Trafficking Unit, National Institute of Dental and Craniofacial Research, National Institutes of Health, Bethesda, MD 20892, USA
| | - Marino Zerial
- Max Planck Institute of Molecular Cell Biology and Genetics, Dresden, Saxony 01307, Germany; Center for Advancing Electronics Dresden, Technische Universität Dresden, Dresden, Saxony 01062, Germany.
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8
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Dos Santos APR, Rocha TL, Borges CL, Bailão AM, de Almeida Soares CM, de Sabóia-Morais SMT. A glyphosate-based herbicide induces histomorphological and protein expression changes in the liver of the female guppy Poecilia reticulata. CHEMOSPHERE 2017; 168:933-943. [PMID: 27836263 DOI: 10.1016/j.chemosphere.2016.10.116] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/10/2016] [Revised: 10/26/2016] [Accepted: 10/27/2016] [Indexed: 06/06/2023]
Abstract
Glyphosate-based herbicides (GBH) are among the most common herbicides found in aquatic systems, but limited data are available about their mode of action and hepatotoxicity in fish. This study investigated the hepatotoxicity induced by GBH in the guppy Poecilia reticulata using a histopathological assessment associated with a proteomic approach. Guppies were exposed to GBH for 24 h at 1.8 mg of glyphosate L-1, corresponding to 50% of the LC50, 96 h. The results indicate that the GBH at 1.8 mg of glyphosate L-1 induce the development of hepatic damage in P. reticulata, which is exposure-time dependent. The histopathological indexes demonstrate that GBH cause inflammatory, regressive, vascular and progressive disorders in the liver of guppies. Using 2D gel electrophoresis associated with mass spectrometry, 18 proteins that changed by GBH were identified and were related to the cellular structure, motility and transport, energy metabolism and apoptosis. The results show that the acute exposure to GBH causes hepatic histopathological damage related to protein expression profile changes in P. reticulata, indicating that a histopathological assessment associated with a proteomic analysis provides a valuable approach to assess the toxic effects of GBH in sentinel fish species.
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Affiliation(s)
- Ana Paula Rezende Dos Santos
- Laboratory of Cellular Behavior, Biological Sciences Institute, Federal University of Goiás, Goiânia, Goiás, Brazil
| | - Thiago Lopes Rocha
- Laboratory of Cellular Behavior, Biological Sciences Institute, Federal University of Goiás, Goiânia, Goiás, Brazil; CIMA, Faculty of Science and Technology, University of Algarve, Campus de Gambelas, Faro, Portugal
| | - Clayton Luiz Borges
- Laboratory of Molecular Biology, Biological Sciences Institute, Federal University of Goiás, Goiânia, Goiás, Brazil
| | - Alexandre Melo Bailão
- Laboratory of Molecular Biology, Biological Sciences Institute, Federal University of Goiás, Goiânia, Goiás, Brazil
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Pollheimer MJ, Fickert P, Stieger B. Chronic cholestatic liver diseases: clues from histopathology for pathogenesis. Mol Aspects Med 2013; 37:35-56. [PMID: 24141039 DOI: 10.1016/j.mam.2013.10.001] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2013] [Revised: 10/04/2013] [Accepted: 10/07/2013] [Indexed: 02/06/2023]
Abstract
Chronic cholestatic liver diseases include fibrosing cholangiopathies such as primary biliary cirrhosis or primary sclerosing cholangitis. These and related cholangiopathies clearly display pathologies associated with (auto)immunologic processes. As the cholangiocyte's apical membrane is exposed to the toxic actions of the bile fluid, the interaction of bile with cholangiocytes and the biliary tree in general must be considered to completely understand the pathogenesis of cholangiopathies. While the molecular processes involved in the hepatocellular formation of bile are well understood in both normal and pathophysiologic conditions, those in the bile ducts of normal liver and in livers with cholangiopathies lag behind. This survey highlights key mechanisms known to date that are important for the formation of bile by hepatocytes and its modification by the biliary tree. It also delineates the clinical pathophysiologic findings for cholangiopathies and puts them in perspective with current experimental models to reveal the pathogenesis of cholangiopathies and develop novel therapeutic approaches.
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Affiliation(s)
- Marion J Pollheimer
- Division of Gastroenterology and Hepatology, Laboratory of Experimental and Molecular Hepatology, Department of Internal Medicine, Medical University of Graz, Austria; Institute of Pathology, Medical University of Graz, Austria
| | - Peter Fickert
- Division of Gastroenterology and Hepatology, Laboratory of Experimental and Molecular Hepatology, Department of Internal Medicine, Medical University of Graz, Austria; Institute of Pathology, Medical University of Graz, Austria.
| | - Bruno Stieger
- Department of Clinical Pharmacology and Toxicology, University Hospital Zurich, Zurich, Switzerland.
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10
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Wang Y, Toh YC, Li Q, Nugraha B, Zheng B, Lu TB, Gao Y, Ng MML, Yu H. Mechanical compaction directly modulates the dynamics of bile canaliculi formation. Integr Biol (Camb) 2013; 5:390-401. [DOI: 10.1039/c2ib20229h] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
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11
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Molnar A, Haybaeck J, Lackner C, Strnad P. The cytoskeleton in nonalcoholic steatohepatitis: 100 years old but still youthful. Expert Rev Gastroenterol Hepatol 2011; 5:167-77. [PMID: 21476912 DOI: 10.1586/egh.11.5] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
The hepatocellular cytoskeleton consists of three filamentous systems: microfilaments, microtubules and keratins (Ks). While the alterations in microfilaments and microtubules during nonalcoholic steatohepatitis (NASH) are largely unexplored, K8/K18 reorganization into Mallory-Denk bodies (MDBs) represents a NASH hallmark, and serological K18 fragments constitute an established tool to monitor NASH severity. To commemorate the 100th anniversary of the first description of MDBs, this article summarizes the composition and function of the hepatocellular cytoskeleton, as well as the importance of cytoskeletal alterations in NASH. The significance of MDBs in clinical routine is illustrated, as are the findings from MDB mouse models, which shape our current view of MDB pathogenesis. Even after 100 years, the cytoskeleton represents a fascinating but greatly understudied area of NASH biology.
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Affiliation(s)
- Agnes Molnar
- Department of Internal Medicine I, University Hospital Ulm, Germany
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12
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Xia L, Ng S, Han R, Tuo X, Xiao G, Leo HL, Cheng T, Yu H. Laminar-flow immediate-overlay hepatocyte sandwich perfusion system for drug hepatotoxicity testing. Biomaterials 2009; 30:5927-36. [PMID: 19646750 DOI: 10.1016/j.biomaterials.2009.07.022] [Citation(s) in RCA: 56] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2009] [Accepted: 07/11/2009] [Indexed: 11/24/2022]
Abstract
Drug hepatotoxicity testing requires in vitro hepatocyte culture to maintain the long-term and stable liver specific functions. We developed a drug testing platform based on laminar-flow immediate-overlay hepatocyte sandwich perfusion culture. The immediate-overlay sandwich (collagen-coated porous polymeric membrane as top overlay) protects the cells and integrity of the top collagen matrix from the impact of flow. A bioreactor was designed that allowed proper control of shear stress and mass transfer. The culture parameters such as the optimal perfusion initiation time and flow rate were systematically and mechanistically determined. The optimized system could re-establish hepatocyte polarity to support biliary excretion and to maintain other liver specific functions, such as the biotransformation enzyme activities, for two weeks that extended the usable in vitro hepatocyte-based drug testing window. When the perfusion cultured hepatocytes from days 7 or 14 were used for drug testing, the APAP-induced hepatotoxicity measurements were more sensitive and consistent over time than the static culture control, enabling further exploitations in large-scale drug testing applications.
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Affiliation(s)
- Lei Xia
- Institute of Bioengineering and Nanotechnology, A*STAR, The Nanos, Singapore, Singapore
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13
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Abstract
The correct functioning of the liver is ensured by the setting and the maintenance of hepatocyte polarity. The complex polarity of the hepatocyte is characterized by the existence of several basolateral and apical poles per cell. Many in vitro models are available for studying hepatocyte polarity, but which are the more suitable? To answer this question, we aimed to identify criteria which determine the typical hepatocyte polarity. Therefore, we compiled a range of protein markers of membrane domains in rat hepatocytes and investigated their involvement in hepatocytic functions. Then, we focused on the relationship between hepatic functions and the cytoskeleton, Golgi apparatus and endoplasmic reticulum. Subsequently, we compared different cell lines expressing hepatocyte polarity. Finally, to demonstrate the usefulness of some of these lines, we presented new data on endoplasmic reticulum organization in relation to polarity.
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14
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Sudo R, Kohara H, Mitaka T, Ikeda M, Tanishita K. Coordinated Movement of Bile Canalicular Networks Reconstructed by Rat Small Hepatocytes. Ann Biomed Eng 2005; 33:696-708. [PMID: 15981869 DOI: 10.1007/s10439-005-1690-5] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
Hepatocytes in vivo have a potential for liver regeneration, but it has been very difficult to reconstruct hepatic organoids in vitro. Recent studies have shown that small hepatocytes (SHs) can reconstruct hepatic organoids including functional bile canaliculi (BC). In the present study we analyzed the movement of BC formed in the hepatic organoids, focusing on the coordination of contraction and dilation among cells and the mechanism producing the coordination. Hepatic cells, including SHs, were isolated from an adult rat liver and cultured. Time-lapse images of BC movements were taken and analyzed in cells treated with or without cytochalasin B (CB). Time-lapse images revealed that all BC, regardless of region contracted in a coordinated manner. Actin filaments were observed along the BC even after the BC networks treated with CB dilated markedly. Microinjection of dye was also carried out to investigate the flow thorough BC. Secreted fluorescein from the injected cell flowed along BC, and gap junctional protein connexin 32 was expressed along BC networks, suggesting cell-to-cell communication. Thus, groups of hepatocytes in the hepatic organoids act in a coordinated manner through intercellular communication.
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Affiliation(s)
- Ryo Sudo
- Center for Life Science and Technology, School of Fundamental Science and Technology, Keio University, 3-14-1 Hiyoshi, Kohoku-ku, Yokohama 223-8522, Japan.
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15
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Li B, Gallin WJ. Differential localization of chicken FIP2 homologue, Ag-9C5, in secretory epithelial cells. Exp Cell Res 2002; 272:135-45. [PMID: 11777338 DOI: 10.1006/excr.2001.5413] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
When hepatocytes polarize, a subset of cellular proteins specifically localizes to the apical cell surface forming the boundary of the bile canaliculus. We have isolated a cDNA encoding a protein recognized by a monoclonal antibody (9C5) that specifically stains the bile canaliculus. The encoded protein (Ag-9C5) is a cytoplasmic protein with three leucine zippers and a zinc finger at the C-terminus. Extensive amino acid sequence similarity indicates that Ag-9C5 is likely the chicken homologue of a human protein, FIP2, which interacts with huntingtin and Rab8. Epitope-tagged Ag-9C5 colocalizes with endogenous Ag-9C5 and other canaliculus marker antigens in transfected organ cultures. In Cos7 cells and MDCK cells Ag-9C5 forms punctate cytoplasmic structures. In intact tissues Ag-9C5 is highly concentrated at the apical surfaces of cells that secrete protein from the apical surfaces, but is found in a fine punctate cytoplasmic pattern in other polarized epithelia. Because this protein has a number of characteristics of proteins that act as scaffolds for assembly of protein complexes (e.g., the cytoplasmic domain of classical cadherins and the FERM superfamily of proteins), it appears that FIP2/Ag-9C5 may act as a scaffold for assembling a complex of proteins that are involved in targeting of some secretory vesicles to defined regions of the cell surface.
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Affiliation(s)
- Bin Li
- Department of Biological Sciences, University of Alberta, Edmonton, Alberta T6G 2E9, Canada
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16
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Ohmi K, Enosawa S, Nonomura Y, Tatsuno T, Ueno Y. Acceleration of actin polymerization and rapid microfilament reorganization in cultured hepatocytes by cyclochlorotin, a hepatotoxic cyclic peptide. Toxicon 2001; 39:303-8. [PMID: 10978748 DOI: 10.1016/s0041-0101(00)00128-8] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
Cyclochlorotin (= chloropeptide, CC) is a hepatotoxic mycotoxin of Penicillium islandicum Sopp. The effect of CC on actin polymerization was examined by the measurement of changes in fluorescence intensity using pyrene-labeled actin and high shear viscosity. In the presence of CC, the time course of actin polymerization was accelerated in a dose dependent manner (2.5 ng/ml-2.5 microg/ml), without affecting the final level of viscosity. CC exerted a strong stabilizing effect on actin, enabling it to maintain its filamentous form in the presence of members of actin-binding proteins, including those of the gelsolin family prepared from hepatocytes. Microscopic observation revealed that in cultured hepatocytes, 1.0 microg/ml of CC induced bleb formation and changes in the microfilament. These observations indicated that after contact of the hepatocyte with CC, the following events were probable. The toxin passed through the cell membrane by a transport system and immediately reacted with the actin-actin binding proteins underlying the lipid bilayer. Bleb formation and hepatotoxicity were thus induced.
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Affiliation(s)
- K Ohmi
- Department of Pathology, National Children's Medical Research Center, Tashido, Tokyo, Japan
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17
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Abstract
The apical surfaces of hepatocytes are specialized to form the boundaries of the bile canaliculi. The canaliculi function to secrete and concentrate components of the bile and to transport the bile out of the interior of the hepatic parenchymal tissue to the epithelium-lined bile ducts. Failure of the canaliculi to form and function properly can lead to biliary stasis or release of bile components into the bloodstream, both potentially life-threatening situations. Experimental analysis of canaliculus development and function has been undertaken in a number of experimental systems, ranging in complexity from intact animals to isolated hepatocyte cell cultures. These approaches each have inherent advantages and disadvantages for studying the various aspects of canaliculus development and function. This article summarizes what is known about how the functional components of the canaliculus develop and the directions that current experimental approaches are leading in analyzing this process. Studies of model epithelial systems have begun to define how interactions between components of the cytoskeleton and plasma membrane regulate the structure of polarized plasma membranes. These results are also discussed in terms of the bile canaliculus.
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Affiliation(s)
- W J Gallin
- Department of Biological Sciences, University of Alberta, Edmonton, Canada
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18
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Song JY, Van Marle J, Van Noorden CJ, Frederiks WM. Disturbed structural interactions between microfilaments and tight junctions in rat hepatocytes during extrahepatic cholestasis induced by common bile duct ligation. Histochem Cell Biol 1996; 106:573-80. [PMID: 8985745 DOI: 10.1007/bf02473272] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
Microfilaments in epithelial cells are important for the structural and functional integrity of tight junctions. In the present study, we examined the relationship between microfilaments and tight junctions in hepatocytes of rat liver following common bile duct ligation (CBDL) for up to 2 weeks. Actin filaments and tight junctions were studied by fluorescence microscopy using 7-nitrobenzene-2-oxa-1,3-diazole phallacidin (NBD-ph) and an anti-ZO-1 antibody, respectively. Double-stained sections were examined with confocal laser scanning microscopy (CLSM). Electron microscopy was applied for the assessment of structural alterations in microfilaments and in tight junctions with detergent-extraction and freeze-fracture preparations. Our results showed that F-actin was present at the entire plasma membrane of hepatocytes in control liver, whereas CBDL increased the amount of F-actin mainly at the bile canalicular and lateral plasma membranes. Simultaneously, the immunofluorescence of ZO-1 underwent striking changes, i.e., from a uniform to an irregular staining pattern with various fluorescence intensities. CLSM demonstrated a colocalization of ZO-1 and F-actin in control liver and its deterioration in CBDL liver. Electron microscopy showed marked alterations of microfilaments and tight junctions due to CBDL. It is concluded that actin filaments are intimately associated with tight junctions in normal hepatocytes. CBDL impairs this association by progressively diminishing the structural interaction between F-actin and ZO-1, which may in turn lead to functional disturbances of tight junctions.
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Affiliation(s)
- J Y Song
- Academic Medical Center, University of Amsterdam, The Netherlands
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20
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Coleman R, Wilton JC, Stone V, Chipman JK. Hepatobiliary function and toxicity in vitro using isolated hepatocyte couplets. GENERAL PHARMACOLOGY 1995; 26:1445-53. [PMID: 8690230 DOI: 10.1016/0306-3623(95)00071-2] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
1. Hepatocyte couplets can be routinely prepared from rat liver to produce a suitable in vitro model for polarized primary cells. 2. Centrifugal elutriation provides a means of producing enriched subpopulations of periportal and perivenous couplets from the same liver, thus providing a means of studying the influence of zonal heterogeneity on hepatobiliary function. 3. The maintenance of structural and secretory polarity demonstrated by hepatocyte couplets provides a convenient in vitro system for mechanistic studies of factors both regulatory and adversely affecting hepatobiliary functions. 4. Couplets are also uniquely appropriate for specific studies of regulation at the biliary pole, on the performance of junctions and on the maintenance and rate of transcytotic movement. 5. The possibility also exists that effects of an in vivo pre-exposure to agents causing hepatobiliary dysfunction can be assessed in couplets ex vivo.
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Affiliation(s)
- R Coleman
- School of Biochemistry, University of Birmingham, UK
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21
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Tsukada N, Azuma T, Phillips MJ. Isolation of the bile canalicular actin-myosin II motor. Proc Natl Acad Sci U S A 1994; 91:6919-23. [PMID: 8041721 PMCID: PMC44309 DOI: 10.1073/pnas.91.15.6919] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023] Open
Abstract
Cytoskeleton-rich canalicular membranes (CCMs) with preserved cytoskeleton and demembranated CCMs, consisting only of cytoskeletal elements, were used to examine the relationship of pericanalicular microfilaments, myosin II phosphorylation, and canalicular contraction. The components of CCMs were visualized by fluorescence microscopy using the filamentous actin probe rhodamine-phalloidin and by electron microscopy, before and after incubation in 1 microM Ca2+/1 mM ATP (contraction solution). Canalicular contraction (luminal closure) was evaluated by morphometric analysis. Myosin II was extracted from CCMs, purified by immunoprecipitation, and analyzed on Western blots. In sequential experiments, autoradiographs of gels from [gamma-32P]-ATP-treated CCMs in the presence or absence of Ca2+ were examined after 0.25, 0.50, 1, 2, 3, 5, and 10 min, and the effects of W7 (a calmodulin antagonist) and ML9 (a myosin light chain kinase inhibitor) were evaluated. The results showed that phosphorylation of the 20-kDa protein was low in controls but enhanced beginning 0.25-0.50 min after addition of contraction solution. Both W7 and ML9 significantly inhibited this reaction and inhibited canalicular contraction. The results indicate that phosphorylation of the regulatory 20-kDa myosin light chain of canaliculus-associated myosin II coincides with or precedes contraction of the canaliculus. We conclude that the canalicular contractile apparatus is composed of actin filaments and a myosin II motor.
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Affiliation(s)
- N Tsukada
- Research Institute, Hospital for Sick Children, Toronto, Ontario, Canada
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Ihrke G, Neufeld EB, Meads T, Shanks MR, Cassio D, Laurent M, Schroer TA, Pagano RE, Hubbard AL. WIF-B cells: an in vitro model for studies of hepatocyte polarity. J Cell Biol 1993; 123:1761-75. [PMID: 7506266 PMCID: PMC2290861 DOI: 10.1083/jcb.123.6.1761] [Citation(s) in RCA: 179] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023] Open
Abstract
We have evaluated the utility of the hepatoma-derived hybrid cell line, WIF-B, for in vitro studies of polarized hepatocyte functions. The majority (> 70%) of cells in confluent culture formed closed spaces with adjacent cells. These bile canalicular-like spaces (BC) accumulated fluorescein, a property of bile canaliculi in vivo. By indirect immunofluorescence, six plasma membrane (PM) proteins showed polarized distributions similar to rat hepatocytes in situ. Four apical PM proteins were concentrated in the BC membrane of WIF-B cells. Microtubules radiated from the BC (apical) membrane, and actin and foci of gamma-tubulin were concentrated in this region. The tight junction-associated protein ZO-1 was present in belts marking the boundary between apical and basolateral PM domains. We explored the functional properties of this boundary in living cells using fluorescent membrane lipid analogs and soluble tracers. When cells were incubated at 4 degrees C with a fluorescent analog of sphingomyelin, only the basolateral PM was labeled. In contrast, when both PM domains were labeled by de novo synthesis of fluorescent sphingomyelin from ceramide, fluorescent lipid could only be removed from the basolateral domain. These data demonstrate the presence of a barrier to the lateral diffusion of lipids between the PM domains. However, small soluble FITC-dextrans (4,400 mol wt) were able to diffuse into BC, while larger FITC-dextrans were restricted to various degrees depending on their size and incubation temperature. At 4 degrees C, the surface labeling reagent sNHS-LC-biotin (557 mol wt) had access to the entire PM, but streptavidin (60,000 mol wt), which binds to biotinylated molecules, was restricted to only the basolateral domain. Such differential accessibility of well-characterized probes can be used to mark each membrane domain separately. These results show that WIF-B cells are a suitable model to study membrane trafficking and targeting in hepatocytes in vitro.
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Affiliation(s)
- G Ihrke
- Department of Cell Biology and Anatomy, Johns Hopkins School of Medicine, Baltimore, Maryland 21205
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