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Poetter-Lang S, Messner A, Bastati N, Ringe KI, Ronot M, Venkatesh SK, Ambros R, Kristic A, Korajac A, Dovjak G, Zalaudek M, Hodge JC, Schramm C, Halilbasic E, Trauner M, Ba-Ssalamah A. Diagnosis of functional strictures in patients with primary sclerosing cholangitis using hepatobiliary contrast-enhanced MRI: a proof-of-concept study. Eur Radiol 2023; 33:9022-9037. [PMID: 37470827 PMCID: PMC10667158 DOI: 10.1007/s00330-023-09915-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2022] [Revised: 04/20/2023] [Accepted: 05/09/2023] [Indexed: 07/21/2023]
Abstract
OBJECTIVES PSC strictures are routinely diagnosed on T2-MRCP as dominant- (DS) or high-grade stricture (HGS). However, high inter-observer variability limits their utility. We introduce the "potential functional stricture" (PFS) on T1-weighted hepatobiliary-phase images of gadoxetic acid-enhanced MR cholangiography (T1-MRC) to assess inter-reader agreement on diagnosis, location, and prognostic value of PFS on T1-MRC vs. DS or HGS on T2-MRCP in PSC patients, using ERCP as the gold standard. METHODS Six blinded readers independently reviewed 129 MRIs to diagnose and locate stricture, if present. DS/HGS was determined on T2-MRCP. On T1-MRC, PFS was diagnosed if no GA excretion was seen in the CBD, hilum or distal RHD, or LHD. If excretion was normal, "no functional stricture" (NFS) was diagnosed. T1-MRC diagnoses (NFS = 87; PFS = 42) were correlated with ERCP, clinical scores, labs, splenic volume, and clinical events. Statistical analyses included Kaplan-Meier curves and Cox regression. RESULTS Interobserver agreement was almost perfect for NFS vs. PFS diagnosis, but fair to moderate for DS and HGS. Forty-four ERCPs in 129 patients (34.1%) were performed, 39 in PFS (92.9%), and, due to clinical suspicion, five in NFS (5.7%) patients. PFS and NFS diagnoses had 100% PPV and 100% NPV, respectively. Labs and clinical scores were significantly worse for PFS vs. NFS. PFS patients underwent more diagnostic and therapeutic ERCPs, experienced more clinical events, and reached significantly more endpoints (p < 0.001) than those with NFS. Multivariate analysis identified PFS as an independent risk factor for liver-related events. CONCLUSION T1-MRC was superior to T2-MRCP for stricture diagnosis, stricture location, and prognostication. CLINICAL RELEVANCE STATEMENT Because half of PSC patients will develop clinically-relevant strictures over the course of the disease, earlier more confident diagnosis and correct localization of functional stricture on gadoxetic acid-enhanced MRI may optimize management and improve prognostication. KEY POINTS • There is no consensus regarding biliary stricture imaging features in PSC that have clinical relevance. • Twenty-minute T1-weighted MRC images correctly classified PSC patients with potential (PFS) vs with no functional stricture (NFS). • T1-MRC diagnoses may reduce the burden of diagnostic ERCPs.
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Affiliation(s)
- Sarah Poetter-Lang
- Department of Biomedical Imaging and Image-Guided Therapy, Medical University Vienna, Vienna, Austria
| | - Alina Messner
- Department of Biomedical Imaging and Image-Guided Therapy, Medical University Vienna, Vienna, Austria
| | - Nina Bastati
- Department of Biomedical Imaging and Image-Guided Therapy, Medical University Vienna, Vienna, Austria
| | - Kristina I Ringe
- Department of Diagnostic and Interventional Radiology, Hannover Medical School, Hannover, Germany
| | - Maxime Ronot
- Department of Medical Imaging at the Beaujon University Hospital in Clichy, University of Paris, Clichy, France
| | - Sudhakar K Venkatesh
- Division of Abdominal Imaging, Department of Radiology, Mayo Clinic, Rochester, MN, USA
| | - Raphael Ambros
- Department of Biomedical Imaging and Image-Guided Therapy, Medical University Vienna, Vienna, Austria
| | - Antonia Kristic
- Department of Biomedical Imaging and Image-Guided Therapy, Medical University Vienna, Vienna, Austria
| | - Aida Korajac
- Department of Biomedical Imaging and Image-Guided Therapy, Medical University Vienna, Vienna, Austria
| | - Gregor Dovjak
- Department of Biomedical Imaging and Image-Guided Therapy, Medical University Vienna, Vienna, Austria
| | - Martin Zalaudek
- Department of Biomedical Imaging and Image-Guided Therapy, Medical University Vienna, Vienna, Austria
| | - Jacqueline C Hodge
- Department of Biomedical Imaging and Image-Guided Therapy, Medical University Vienna, Vienna, Austria
| | - Christoph Schramm
- Department of Gastroenterology, Hepatology, University Medical Center Hamburg - Eppendorf, Hamburg, Germany
| | - Emina Halilbasic
- Division of Gastroenterology and Hepatology, Department of Internal Medicine III, Medical University of Vienna, General Hospital of Vienna (AKH), Vienna, Austria
| | - Michael Trauner
- Division of Gastroenterology and Hepatology, Department of Internal Medicine III, Medical University of Vienna, General Hospital of Vienna (AKH), Vienna, Austria
| | - Ahmed Ba-Ssalamah
- Department of Biomedical Imaging and Image-Guided Therapy, Medical University Vienna, Vienna, Austria.
- Department of Biomedical Imaging and Image-Guided Therapy, General Hospital of Vienna (AKH), Medical University Vienna, Waehringer Guertel 18-20, 1090, Vienna, Austria.
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Lee YS, Seki E. In Vivo and In Vitro Models to Study Liver Fibrosis: Mechanisms and Limitations. Cell Mol Gastroenterol Hepatol 2023; 16:355-367. [PMID: 37270060 PMCID: PMC10444957 DOI: 10.1016/j.jcmgh.2023.05.010] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/04/2023] [Revised: 05/26/2023] [Accepted: 05/26/2023] [Indexed: 06/05/2023]
Abstract
Liver fibrosis is a common result of liver injury owing to various kinds of chronic liver diseases. A deeper understanding of the pathophysiology of liver fibrosis and identifying potential therapeutic targets of liver fibrosis is important because liver fibrosis may progress to advanced liver diseases, such as cirrhosis and hepatocellular carcinoma. Despite numerous studies, the underlying mechanisms of liver fibrosis remain unclear. Mechanisms of the development and progression of liver fibrosis differ according to etiologies. Therefore, appropriate liver fibrosis models should be selected according to the purpose of the study and the type of underlying disease. Many in vivo animal and in vitro models have been developed to study liver fibrosis. However, there are no perfect preclinical models for liver fibrosis. In this review, we summarize the current in vivo and in vitro models for studying liver fibrosis and highlight emerging in vitro models, including organoids and liver-on-a-chip models. In addition, we discuss the mechanisms and limitations of each model.
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Affiliation(s)
- Young-Sun Lee
- Karsh Division of Gastroenterology and Hepatology, Department of Medicine, Cedars-Sinai Medical Center, Los Angeles, California; Department of Internal Medicine, Korea University College of Medicine, Seoul, South Korea
| | - Ekihiro Seki
- Karsh Division of Gastroenterology and Hepatology, Department of Medicine, Cedars-Sinai Medical Center, Los Angeles, California.
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Zeng J, Fan J, Zhou H. Bile acid-mediated signaling in cholestatic liver diseases. Cell Biosci 2023; 13:77. [PMID: 37120573 PMCID: PMC10149012 DOI: 10.1186/s13578-023-01035-1] [Citation(s) in RCA: 14] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2023] [Accepted: 04/18/2023] [Indexed: 05/01/2023] Open
Abstract
Chronic cholestatic liver diseases, such as primary biliary cholangitis (PBC) and primary sclerosing cholangitis (PSC), are associated with bile stasis and gradually progress to fibrosis, cirrhosis, and liver failure, which requires liver transplantation. Although ursodeoxycholic acid is effective in slowing the disease progression of PBC, it has limited efficacy in PSC patients. It is challenging to develop effective therapeutic agents due to the limited understanding of disease pathogenesis. During the last decade, numerous studies have demonstrated that disruption of bile acid (BA) metabolism and intrahepatic circulation promotes the progression of cholestatic liver diseases. BAs not only play an essential role in nutrition absorption as detergents but also play an important role in regulating hepatic metabolism and modulating immune responses as key signaling molecules. Several excellent papers have recently reviewed the role of BAs in metabolic liver diseases. This review focuses on BA-mediated signaling in cholestatic liver disease.
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Affiliation(s)
- Jing Zeng
- Department of Microbiology and Immunology, Medical College of Virginia and Richmond VA Medical Center, Central Virginia Veterans Healthcare System, Virginia Commonwealth University, 1220 East Broad Street, MMRB-5044, Richmond, VA, 23298-0678, USA
- Department of Gastroenterology, Xinhua Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, 200092, China
| | - Jiangao Fan
- Department of Gastroenterology, Xinhua Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, 200092, China
| | - Huiping Zhou
- Department of Microbiology and Immunology, Medical College of Virginia and Richmond VA Medical Center, Central Virginia Veterans Healthcare System, Virginia Commonwealth University, 1220 East Broad Street, MMRB-5044, Richmond, VA, 23298-0678, USA.
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Wu H, Chen C, Ziani S, Nelson LJ, Ávila MA, Nevzorova YA, Cubero FJ. Fibrotic Events in the Progression of Cholestatic Liver Disease. Cells 2021; 10:cells10051107. [PMID: 34062960 PMCID: PMC8147992 DOI: 10.3390/cells10051107] [Citation(s) in RCA: 28] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2021] [Revised: 04/28/2021] [Accepted: 04/30/2021] [Indexed: 02/07/2023] Open
Abstract
Cholestatic liver diseases including primary biliary cholangitis (PBC) and primary sclerosing cholangitis (PSC) are associated with active hepatic fibrogenesis, which can ultimately lead to the development of cirrhosis. However, the exact relationship between the development of liver fibrosis and the progression of cholestatic liver disease remains elusive. Periductular fibroblasts located around the bile ducts seem biologically different from hepatic stellate cells (HSCs). The fibrotic events in these clinical conditions appear to be related to complex crosstalk between immune/inflammatory mechanisms, cytokine signalling, and perturbed homeostasis between cholangiocytes and mesenchymal cells. Several animal models including bile duct ligation (BDL) and the Mdr2-knockout mice have improved our understanding of mechanisms underlying chronic cholestasis. In the present review, we aim to elucidate the mechanisms of fibrosis in order to help to identify potential diagnostic and therapeutic targets.
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Affiliation(s)
- Hanghang Wu
- Department of Immunology, Ophthalmology & ENT, Complutense University School of Medicine, 28040 Madrid, Spain; (H.W.); (C.C.); (S.Z.); (Y.A.N.)
| | - Chaobo Chen
- Department of Immunology, Ophthalmology & ENT, Complutense University School of Medicine, 28040 Madrid, Spain; (H.W.); (C.C.); (S.Z.); (Y.A.N.)
- Health Research Institute Gregorio Marañón (IiSGM), 28007 Madrid, Spain
- Department of General Surgery, Wuxi Xishan People’s Hospital, Wuxi 214000, China
| | - Siham Ziani
- Department of Immunology, Ophthalmology & ENT, Complutense University School of Medicine, 28040 Madrid, Spain; (H.W.); (C.C.); (S.Z.); (Y.A.N.)
| | - Leonard J. Nelson
- Institute for Bioengineering (IBioE), School of Engineering, Faraday Building, The University of Edinburgh, Edinburgh EH9 3 JL, Scotland, UK;
- Institute of Biological Chemistry, Biophysics and Bioengineering (IB3), School of Engineering and Physical Sciences (EPS), Heriot-Watt University, Edinburgh EH14 4AS, Scotland, UK
| | - Matías A. Ávila
- Hepatology Program, Center for Applied Medical Research (CIMA), University of Navarra, 31008 Pamplona, Spain;
- Centro de Investigacion Biomedica en Red, Enfermedades Hepáticas y Digestivas (CIBERehd), 28029 Madrid, Spain
- Instituto de Investigaciones Sanitarias de Navarra IdiSNA, 31008 Pamplona, Spain
| | - Yulia A. Nevzorova
- Department of Immunology, Ophthalmology & ENT, Complutense University School of Medicine, 28040 Madrid, Spain; (H.W.); (C.C.); (S.Z.); (Y.A.N.)
- Health Research Institute Gregorio Marañón (IiSGM), 28007 Madrid, Spain
- Centro de Investigacion Biomedica en Red, Enfermedades Hepáticas y Digestivas (CIBERehd), 28029 Madrid, Spain
- Department of Internal Medicine III, University Hospital RWTH Aachen, 52074 Aachen, Germany
| | - Francisco Javier Cubero
- Department of Immunology, Ophthalmology & ENT, Complutense University School of Medicine, 28040 Madrid, Spain; (H.W.); (C.C.); (S.Z.); (Y.A.N.)
- Health Research Institute Gregorio Marañón (IiSGM), 28007 Madrid, Spain
- Centro de Investigacion Biomedica en Red, Enfermedades Hepáticas y Digestivas (CIBERehd), 28029 Madrid, Spain
- Correspondence: ; Tel.: +34-91-394-1385; Fax: +34-91-394-1641
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Yang QL, Yang F, Gong JT, Tang XW, Wang GY, Wang ZT, Yang L. Sweroside ameliorates α-naphthylisothiocyanate-induced cholestatic liver injury in mice by regulating bile acids and suppressing pro-inflammatory responses. Acta Pharmacol Sin 2016; 37:1218-28. [PMID: 27498779 DOI: 10.1038/aps.2016.86] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2015] [Accepted: 02/06/2016] [Indexed: 12/18/2022] Open
Abstract
AIM Sweroside is an iridoid glycoside with diverse biological activities. In the present study we investigated the effects of sweroside on α-naphthylisothiocyanate (ANIT)-induced cholestatic liver injury in mice. METHODS Mice received sweroside (120 mg·kg(-1)·d(-1), ig) or a positive control INT-747 (12 mg·kg(-1)·d(-1), ig) for 5 d, and ANIT (75 mg/kg, ig) was administered on d 3. The mice were euthanized on d 5, and serum biochemical markers, hepatic bile acids and histological changes were analyzed. Hepatic expression of genes related to pro-inflammatory mediators and bile acid metabolism was also assessed. Primary mouse hepatocytes were exposed to a reconstituted mixture of hepatic bile acids, which were markedly elevated in the ANIT-treated mice, and the cell viability and expression of genes related to pro-inflammatory mediators were examined. RESULTS Administration of sweroside or INT-747 effectively ameliorated ANIT-induced cholestatic liver injury in mice, as evidenced by significantly reduced serum biochemical markers and attenuated pathological changes in liver tissues. Furthermore, administration of sweroside or INT-747 significantly decreased ANIT-induced elevation of individual hepatic bile acids, such as β-MCA, CA, and TCA, which were related to its effects on the expression of genes responsible for bile acid synthesis and transport as well as pro-inflammatory responses. Treatment of mouse hepatocytes with the reconstituted bile acid mixture induced significant pro-inflammatory responses without affecting the cell viability. CONCLUSION Sweroside attenuates ANIT-induced cholestatic liver injury in mice by restoring bile acid synthesis and transport to their normal levels, as well as suppressing pro-inflammatory responses.
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Abstract
Cholestatic liver diseases encompass a wide spectrum of disorders with different causes, resulting in impaired bile flow and accumulation of bile acids and other potentially hepatotoxic cholephils. The understanding of the molecular mechanisms of bile formation and cholestasis has recently improved significantly through new insights into nuclear receptor (patho)biology. Nuclear receptors are ligand-activated transcription factors, which act as central players in the regulation of genes responsible for elimination and detoxification of biliary constituents accumulating in cholestasis. They also control other pathophysiologic processes such as inflammation, fibrogenesis, and carcinogenesis involved in the pathogenesis and disease progression of cholestasis liver diseases.
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Affiliation(s)
- Emina Halilbasic
- Division of Gastroenterology and Hepatology, Department of Internal Medicine III, Medical University of Vienna, Vienna, Austria
| | - Anna Baghdasaryan
- Division of Gastroenterology and Hepatology, Department of Internal Medicine III, Medical University of Vienna, Vienna, Austria
- Laboratory of Experimental and Molecular Hepatology, Division of Gastroenterology and Hepatology, Department of Internal Medicine, Medical University of Graz, Graz, Austria
| | - Michael Trauner
- Division of Gastroenterology and Hepatology, Department of Internal Medicine III, Medical University of Vienna, Vienna, Austria
- Corresponding author. Division of Gastroenterology and Hepatology, Department of Internal Medicine III, Medical University of Vienna, Waehringer Guertel 18-20, A-1090 Vienna, Vienna, Austria.
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Zollner G, Wagner M, Trauner M. Nuclear receptors as drug targets in cholestasis and drug-induced hepatotoxicity. Pharmacol Ther 2010; 126:228-43. [PMID: 20388526 DOI: 10.1016/j.pharmthera.2010.03.005] [Citation(s) in RCA: 67] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2010] [Accepted: 03/24/2010] [Indexed: 01/04/2023]
Abstract
Nuclear receptors are key regulators of various processes including reproduction, development, and metabolism of xeno- and endobiotics such as bile acids and drugs. Research in the last two decades provided researchers and clinicians with a detailed understanding of the regulation of these processes and, most importantly, also prompted the development of novel drugs specifically targeting nuclear receptors for the treatment of a variety of diseases. Some nuclear receptor agonists are already used in daily clinical practice but many more are currently designed or tested for the treatment of diabetes, dyslipidemia, fatty liver disease, cancer, drug hepatotoxicity and cholestasis. The hydrophilic bile acid ursodeoxycholic acid is currently the only available drug to treat cholestasis but its efficacy is limited. Therefore, development of novel treatments represents a major goal for both pharmaceutical industry and academic researchers. Targeting nuclear receptors in cholestasis is an intriguing approach since these receptors are critically involved in regulation of bile acid homeostasis. This review will discuss the general role of nuclear receptors in regulation of transporters and other enzymes maintaining bile acid homeostasis and will review the role of individual receptors as therapeutic targets. In addition, the central role of nuclear receptors and other transcription factors such as the aryl hydrocarbon receptor (AhR) and the nuclear factor-E2-related factor (Nrf2) in mediating drug disposition and their potential therapeutic role in drug-induced liver disease will be covered.
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Affiliation(s)
- Gernot Zollner
- Laboratory of Experimental and Molecular Hepatology, Division of Gastroenterology and Hepatology, Department of Internal Medicine, Medical University Graz, Auenbruggerplatz 15, A-8036 Graz, Austria
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Fickert P, Stöger U, Fuchsbichler A, Moustafa T, Marschall HU, Weiglein AH, Tsybrovskyy O, Jaeschke H, Zatloukal K, Denk H, Trauner M. A new xenobiotic-induced mouse model of sclerosing cholangitis and biliary fibrosis. THE AMERICAN JOURNAL OF PATHOLOGY 2007; 171:525-36. [PMID: 17600122 PMCID: PMC1934539 DOI: 10.2353/ajpath.2007.061133] [Citation(s) in RCA: 264] [Impact Index Per Article: 15.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
Xenobiotics and drugs may lead to cholangiopathies and biliary fibrosis, but the underlying mechanisms are largely unknown. Therefore, we aimed to characterize the cause and consequences of hepatobiliary injury and biliary fibrosis in 3,5-diethoxycarbonyl-1,4-dihydrocollidine (DDC)-fed mice as a novel model of xenobiotic-induced cholangiopathy. Liver morphology, markers of inflammation, cell proliferation, fibrosis, bile formation, biliary porphyrin secretion, and hepatobiliary transporter expression were studied longitudinally in DDC- and control diet-fed Swiss albino mice. DDC feeding led to increased biliary porphyrin secretion and induction of vascular cell adhesion molecule, osteopontin, and tumor necrosis factor-alpha expression in bile duct epithelial cells. This was associated with a pronounced pericholangitis with a significantly increased number of CD11b-positive cells, ductular reaction, and activation of periductal myofibroblasts, leading to large duct disease and a biliary type of liver fibrosis. After 4 weeks, we constantly observed intraductal porphyrin pigment plugs. Glutathione and phospholipid excretion significantly decreased over time. Expression of Ntcp, Oatp4, and Mrp2 was significantly reduced, whereas Bsep expression remained unchanged and adaptive Mrp3 and Mrp4 expression was significantly induced. We demonstrate that DDC feeding in mice leads to i) a reactive phenotype of cholangiocytes and bile duct injury, ii) pericholangitis, periductal fibrosis, ductular reaction, and consequently portal-portal bridging, iii) down-regulation of Mrp2 and impaired glutathione excretion, and iv) segmental bile duct obstruction. This model may be valuable to investigate the mechanisms of xenobiotic-induced chronic cholangiopathies and its sequels including biliary fibrosis.
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Affiliation(s)
- Peter Fickert
- Laboratory of Experimental and Molecular Hepatology, Division of Gastroenterology and Hepatology, Department of Medicine, Medical University Graz, Austria
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Abstract
Cholestasis is the failure of bile to reach duodenum due to three different mechanisms: a. alteration of bile secretion by hepatocytes into the canaliculus with or without liver cell damage; b. obstruction of the intrahepatic bile ducts caused by diseases of ductules or small/medium bile ducts; c. obstruction of extrahepatic bile ducts. This short review focuses on drugs which may induce cholestasis by any of these mechanisms.
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Affiliation(s)
- Claude Degott
- Hopital Beajuon, Service D'Anatomie et de Cytologie Pathologique, Clichy, France
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Abstract
From considerations of hepatic physiology and pathology coupled with pharmacokinetic principles, it appears that altered drug elimination in liver disease may result from the following mechanisms: reduction in absolute cell mass, in cellular enzyme content and/or activity, in portal vein perfusion due to extrahepatic/intrahepatic shunting, or of portal perfusion of hepatocyte mass due to decreased portal flow or sinusoidal perfusion; increase in arterial perfusion relative to portal perfusion; preferential perfusion of the sinusoidal midzone and terminal zones by arterioles; potential for direct mixing of arterial blood within the space of Disse; reduced exchange across the endothelial lining; and impaired diffusion within the space of Disse. In general, oxidative drug metabolism is impaired in liver disease and the degree of impairment of oxidisation differs between drugs but correlates best with the degree of sinusoidal capillarisation, i.e. the degree of access of the drug from the sinusoid to the hepatocyte. Drug conjugation appears to be relatively unaffected by liver disease, whereas elimination by biliary excretion correlates best with the degree of intrahepatic shunting and not with sinusoidal capillarisation. As the latter should impair hepatocyte access of all compounds similarly, a potentially important mechanism could be impaired access of oxygen to hepatocytes as oxidative metabolism is much more sensitive to oxygen supply than are conjugation or biliary excretion. This suggests a potentially important therapeutic role for agents which increase the hepatic oxygen supply. Useful adjunctive strategies may also derive from the oxygen limitation hypothesis. Anaemia should be targeted as a critically important variable, as should oxygen-carrying capacity, i.e. modification of the smoking habit. Additionally, enzyme inducers such as barbiturates may be used if overriding hypoxic constraints are removed by oxygen supplementation. Agents likely to seriously compromise arterial perfusion of the hepatic vascular bed should be avoided, e.g. those causing postural hypotension or vasospasm. Vasodilators can be used to actively promote arterial perfusion. While the effect of liver disease on drug handling is highly variable and difficult to predict, there are well recognised principles for modifying dosage. These include halving the dose of drugs given systemically (or of low clearance drugs given orally) and a 50 to 90% reduction in the dose of drugs with a high hepatic clearance given orally. Changes in the pharmacodynamic effects of drugs (either alone or in addition to pharmacokinetic changes) can also be profound, and awareness of this possibility should be increased.
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Affiliation(s)
- A J McLean
- Clinical Pharmacology Department, Alfred Hospital, Melbourne, Victoria, Australia
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Abstract
A large number of drugs may be associated with impaired bile flow. Drug-associated cholestasis presents like other forms of cholestasis with pale stools, dark urine, pruritus and jaundice. Abdominal pain may be present in some instances and can be so severe as to lead to a false diagnosis of acute cholecystitis. Biochemically, drug-associated cholestasis resembles other forms of cholestasis although the presence of eosinophilia may suggest drug involvement. Many types of drug-induced cholestasis run a benign course with resolution of signs and symptoms within 3 months but occasionally the jaundice can take a year or more to resolve. Progression to cirrhosis is uncommon. Some patients may develop a syndrome resembling primary biliary cirrhosis. The mechanisms of drug-associated cholestasis are uncertain but may arise from alteration of bile formation within the hepatocyte or bile excretion at the level of the canaliculus or the extrahepatic ducts. Histological examination of the liver may be helpful in classifying the types of jaundice but the diagnosis of drug-induced cholestasis is usually one of temporal association and exclusion of other causes.
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Abstract
Acute, drug-induced hepatocellular cholestasis (either pure or cholestatic hepatitis) is a common manifestation of drug-induced hepatic injury. The drugs most frequently responsible are hormonal steroids and psychopharmacological agents (in particular phenothiazines and some antidepressants). Cholestasis usually subsides without sequelae in less than six months. Acute, drug-induced ductular cholestasis is uncommon and can resemble biliary tract obstruction. Complete recovery occurs promptly after the withdrawal of the causative drug in most cases. The pathogenetic mechanism may be immunoallergic. Prolonged ductular or ductal cholestasis can follow drug-induced acute hepatitis despite prompt withdrawal of the offending drug. This syndrome, observed mainly with chlorpromazine and uncommonly with twenty other drugs, is characterized by the progressive disappearance of small bile ducts and by manifestations mimicking primary biliary cirrhosis. However, its prognosis appears to be better than that of primary biliary cirrhosis, the condition being reversible in the majority of cases or even subsiding completely. The mechanism is still unknown, but several features suggest some form of autoimmunity. Extrahepatic cholestasis related to sclerosing cholangitis is a frequent and long-term complication of intra-arterial infusion of floxuridine in patients treated for hepatic metastases from colorectal carcinoma. Although it may be reversible, floxuridine-induced sclerosing cholangitis has a poor prognosis and can lead to death in a few patients. The mechanism is probably related to the vascular supply of the common hepatic duct and its relationship to the perfusion territory of floxuridine.
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Abstract
Intrahepatic cholestasis, defined as arrested bile flow, mimics extrahepatic obstruction in its biochemical, clinical and morphological features. It may be due to hepatocyte lesions of which there are three types, termed canalicular, hepatocanalicular and hepatocellular, respectively; or it may be due to ductal lesions at the level of the cholangiole or portal or septal ducts. Defective bile flow due to hepatic lesions reflects abnormal modification of the ductular bile. Defective formation of canalicular bile may involve bile acid-dependent or independent flow. It appears to result most importantly from defective secretion of bile acid-dependent flow secondary to defective uptake from sinusoidal blood, defective transcellular transport and defective secretion; or from regurgitation of secreted bile via leaky tight junctions. An independent defect in bile acid-independent flow is less clear. Defective flow of bile along the canaliculus may reflect increased viscosity and impaired canalicular contractility secondary to injury of the pericanalicular microfibrillar network. Impaired flow beyond the canaliculus may result from ductal injury. Sites of lesions that contribute to cholestasis include the sinusoidal and canalicular plasma membrane, the pericanalicular network and the tight junction and, less certainly, microtubules and microfilaments and Golgi apparatus. A number of drugs that lead to cholestasis have been found to lead to injury at one or more of these sites. Other agents (alpha-naphthylisothiocyanate, methylenedianiline, contaminated rapeseed oil, paraquat) lead to ductal injury resulting in cholestasis. Reports of inspissated casts in ductules (benoxaprofen jaundice) and injury to the major excretory tree (5-fluorouridine after hepatic artery infusion) have led to other forms of ductal cholestasis. Most instances of drug-induced cholestasis present as acute, transient illness, although important chronic forms also occur. The clinical features include the reflection of the cholestasis (pruritus, jaundice), systemic manifestations and extrahepatic organ involvement. While nearly all classes of medicinal agents include some that can lead to cholestasis, there are differences among the various categories. Phenothiazines and related antipsychotic and 'tranquillizer' drugs characteristically lead to cholestatic hepatic injury. The tricyclic antidepressants may lead to cholestatic or hepatocellular injury.(ABSTRACT TRUNCATED AT 400 WORDS)
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Abstract
The clinical, biochemical and histological characteristics of 13 cases of acute hepatitis A were evaluated. In 10 biopsies moderate to severe cholestasis was seen consisting of bile thrombi, cholestatic liver cell rosettes and ductular transformation of hepatocytes as shown on keratin- and S-100 immunostaining. The periportal spotty necrosis may play a role in the pathogenesis of cholestasis in hepatitis A by creating an interruption in continuity of bile flow. In 6 cases, abnormal ductular epithelium was seen resembling the ductular lesion in septicemia. Such ductular lesion may be related to the accumulation of leucotrienes as a result of cholestasis.
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