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Mak KM, Shekhar AC. Lipopolysaccharide, arbiter of the gut-liver axis, modulates hepatic cell pathophysiology in alcoholism. Anat Rec (Hoboken) 2025; 308:975-1004. [PMID: 39166429 DOI: 10.1002/ar.25562] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2024] [Revised: 07/18/2024] [Accepted: 08/06/2024] [Indexed: 08/22/2024]
Abstract
Over the last four decades, clinical research and experimental studies have established that lipopolysaccharide (LPS)-a component of the outer membrane of gram-negative bacteria-is a potent hepatotoxic molecule in humans and animals. Alcohol abuse is commonly associated with LPS endotoxemia. This review highlights LPS molecular structures and modes of release from bacteria, plasma LPS concentrations, induction of microbiota dysbiosis, disruption of gut epithelial barrier, and translocation of LPS into the portal circulation impacting the pathophysiology of hepatic cells via the gut-liver axis. We describe and illustrate the portal vein circulation and its distributaries draining the gastrointestinal tract. We also elaborate on the gut-liver axis coupled with enterohepatic circulation that represents a bidirectional communication between the gut and liver. The review also updates the data on how circulating LPS is cleared in a coordinated effort between Kupffer cells, hepatocytes, and liver sinusoidal endothelial cells. Significantly, the article reviews and updates the modes/mechanisms of action by which LPS mediates the diverse pathophysiology of Kupffer cells, hepatocytes, sinusoidal endothelial cells, and hepatic stellate cells primarily in association with alcohol consumption. Specifically, we review the intricate linkages between ethanol, microbiota dysbiosis, LPS production, gut-liver axis, and pathophysiology of various hepatic cells. The maintenance of the gut barrier structural and functional integrity and microbiome homeostasis is essential in mitigating alcoholic liver disease and improving liver health.
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Affiliation(s)
- Ki M Mak
- Department of Medical Education, Icahn School of Medicine at Mount Sinai, New York, New York, USA
| | - Aditya C Shekhar
- Department of Medical Education, Icahn School of Medicine at Mount Sinai, New York, New York, USA
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Liu H, Li MJ, Zhang XN, Wang S, Li LX, Guo FF, Zeng T. N,N-dimethylformamide-induced acute liver damage is driven by the activation of NLRP3 inflammasome in liver macrophages of mice. ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY 2022; 238:113609. [PMID: 35551047 DOI: 10.1016/j.ecoenv.2022.113609] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/22/2022] [Revised: 04/27/2022] [Accepted: 05/02/2022] [Indexed: 06/15/2023]
Abstract
N,N-dimethylformamide (DMF) is a non-negligible volatile hazardous material in indoor and outdoor environments. Although the hepatotoxicity of DMF has been well recognized, the underlying mechanisms remain unclear and prophylactic medicine is still lacking. Herein, we established a DMF-induced acute liver injury mouse model and investigated the underlying mechanisms focusing on oxidative stress and the nucleotide-binding domain and leucine-rich repeat receptor (NLR) family pyrin domain (PYD)-containing 3 (NLRP3) inflammasome. DMF was found to induce oxidative stress, evidenced by the elevation of hepatic malondialdehyde (MDA) and 4-hydroxynonenal (4-HNE) adducts levels, and the decline of reduced glutathione (GSH) levels. However, neither N-acetyl cysteine (NAC) nor sulforaphane (SF) ameliorated the hepatoxicity induced by DMF in mice. Interestingly, DMF exposure led to focal necrosis of hepatocytes and NLRP3 inflammasome activation before the onset of obvious liver damage. In addition, DMF exposure induced infiltration and proinflammatory/M1 polarization of macrophages in mice livers. Furthermore, the inactivation of hepatic macrophages by GdCl3 significantly suppressed DMF-induced elevation of serum aminotransferase activities, neutrophile infiltration, and activation of NLRP3 inflammasome in mice liver. Collectively, these results suggest that DMF-induced acute hepatotoxicity may be attributed to the activation of NLRP3 inflammasome in liver macrophages, but not oxidative stress.
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Affiliation(s)
- Hong Liu
- Institute of Toxicology, School of Public Health, Cheeloo College of Medicine, Shandong University, Jinan, Shandong 250012, China
| | - Ming-Jun Li
- Institute of Toxicology, School of Public Health, Cheeloo College of Medicine, Shandong University, Jinan, Shandong 250012, China; Tangshan Vocational&Technical College, Tangshan, Hebei 063000, China
| | - Xiu-Ning Zhang
- Institute of Toxicology, School of Public Health, Cheeloo College of Medicine, Shandong University, Jinan, Shandong 250012, China
| | - Shuo Wang
- School of Pharmaceutical Sciences, Liaocheng University, Liaocheng, Shandong Province 252059, China
| | - Long-Xia Li
- Institute of Toxicology, School of Public Health, Cheeloo College of Medicine, Shandong University, Jinan, Shandong 250012, China
| | - Fang-Fang Guo
- Department of Pharmacy, Qilu Hospital, Cheeloo College of Medicine, Shandong University, Jinan, Shandong 250012, China.
| | - Tao Zeng
- Institute of Toxicology, School of Public Health, Cheeloo College of Medicine, Shandong University, Jinan, Shandong 250012, China.
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Abstract
Nonalcoholic fatty liver disease (NAFLD) is the hepatic manifestation of cardiometabolic syndrome, which often also includes obesity, diabetes, and dyslipidemia. It is rapidly becoming the most prevalent liver disease worldwide. A sizable minority of NAFLD patients develop nonalcoholic steatohepatitis (NASH), which is characterized by inflammatory changes that can lead to progressive liver damage, cirrhosis, and hepatocellular carcinoma. Recent studies have shown that in addition to genetic predisposition and diet, the gut microbiota affects hepatic carbohydrate and lipid metabolism as well as influences the balance between pro‐inflammatory and anti‐inflammatory effectors in the liver, thereby impacting NAFLD and its progression to NASH. In this review, we will explore the impact of gut microbiota and microbiota‐derived compounds on the development and progression of NAFLD and NASH, and the unexplored factors related to potential microbiome contributions to this common liver disease.
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Affiliation(s)
| | - Danping Zheng
- Immunology Department, Weizmann Institute of Science, Rehovot, Israel.,Department of Gastroenterology, The First Affiliated Hospital Sun Yat-sen University, Guangzhou, China
| | - Oren Shibolet
- Department of Gastroenterology and Liver Disease, Tel Aviv Sourasky Medical Center, Tel Aviv, Israel.,Sackler Faculty of Medicine, Tel Aviv Sourasky Medical Center, Tel Aviv, Israel
| | - Eran Elinav
- Immunology Department, Weizmann Institute of Science, Rehovot, Israel
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Gaddam RR, Chambers S, Fraser R, Cogger VC, Le Couteur DG, Ishii I, Bhatia M. Cystathionine-Gamma-Lyase-Derived Hydrogen Sulfide-Regulated Substance P Modulates Liver Sieve Fenestrations in Caecal Ligation and Puncture-Induced Sepsis. Int J Mol Sci 2019; 20:3191. [PMID: 31261857 PMCID: PMC6651477 DOI: 10.3390/ijms20133191] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2019] [Revised: 06/27/2019] [Accepted: 06/27/2019] [Indexed: 12/20/2022] Open
Abstract
Cystathionine-γ-lyase (CSE) isa hydrogen sulfide (H2S)-synthesizing enzyme that promotesinflammation by upregulating H2S in sepsis. Liver sinusoidal endothelial cells (LSECs) are fenestrated endothelial cells (liver sieve) that undergo alteration during sepsis and H2S plays a role in this process. Substance P (SP) is encoded by the preprotachykinin A (PPTA) gene, and promotes inflammation in sepsis; however, its regulation by H2S is poorly understood. Furthermore, the interaction between H2S and SP in modulating LSEC fenestrations following sepsis remains unclear. This study aimed to investigate whether CSE/H2S regulates SP and the neurokinin-1 receptor (NK-1R) andmodulates fenestrations in LSECs following caecalligation and puncture (CLP)-induced sepsis. Here we report thatthe absence of either CSE or H2S protects against liver sieve defenestration and gaps formation in LSECsin sepsis by decreased SP-NK-1R signaling. Following sepsis, there is an increased expression of liver CSE and H2S synthesis, and plasma H2S levels, which were aligned with higher SP levels in the liver, lungs and plasma and NK-1R in the liver and lungs. The genetic deletion of CSE led to decreased sepsis-induced SP and NK-1R in the liver, lungs and plasma SP suggesting H2S synthesized through CSE regulates the SP-NK-1R pathway in sepsis. Further, mice deficient in the SP-encoding gene (PPTA) preservedsepsis-induced LSEC defenestrationand gaps formation, as seen by maintenance of patent fenestrations and fewer gaps. In conclusion, CSE/H2S regulates SP-NK-1R and modulates LSEC fenestrations in sepsis.
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Affiliation(s)
- Ravinder R Gaddam
- Department of Pathology and Biomedical Science, University of Otago, Christchurch 8140, New Zealand
| | - Stephen Chambers
- Department of Pathology and Biomedical Science, University of Otago, Christchurch 8140, New Zealand
| | - Robin Fraser
- Department of Pathology and Biomedical Science, University of Otago, Christchurch 8140, New Zealand
| | - Victoria C Cogger
- Ageing and Alzheimers Institute, ANZAC Research Institute, University of Sydney and Concord Hospital, Sydney 2139, Australia
| | - David G Le Couteur
- Ageing and Alzheimers Institute, ANZAC Research Institute, University of Sydney and Concord Hospital, Sydney 2139, Australia
| | - Isao Ishii
- Showa Pharmaceutical University, Machida 194-8543, Japan
| | - Madhav Bhatia
- Department of Pathology and Biomedical Science, University of Otago, Christchurch 8140, New Zealand.
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Kus E, Jasiński K, Skórka T, Czyzynska-Cichon I, Chlopicki S. Short-term treatment with hepatoselective NO donor V-PYRRO/NO improves blood flow in hepatic microcirculation in liver steatosis in mice. Pharmacol Rep 2017; 70:463-469. [PMID: 29631249 DOI: 10.1016/j.pharep.2017.11.019] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2017] [Revised: 09/28/2017] [Accepted: 11/29/2017] [Indexed: 12/12/2022]
Abstract
BACKGROUND The impairment of liver sinusoidal endothelial cells (LSECs) function and diminished nitric oxide (NO) production has been regarded as an important pathogenic factor in liver steatosis. Restoring NO-dependent function was shown to counteract liver steatosis, obesity, and insulin resistance. However, it is not known whether restored liver perfusion and improvement in hepatic blood flow contributes to the anti-steatotic effects of NO. Taking advantage of in vivo MRI, we have examined the effects of short-term treatment with the hepatoselective NO donor V-PYRRO/NO on hepatic microcirculation in advanced liver steatosis. METHODS Male C57BL/6 mice fed for six months a high fat diet (HFD; 60 kcal% of fat) were treated for 3 weeks with V-PYRRO/NO (twice a day 5mg/kg b.w. ip). An MRI assessment of liver perfusion using the FAIR-EPI method and a portal vein blood flow using the FLASH method were performed. Blood biochemistry, glucose tolerance tests, a histological evaluation of the liver, and liver NO concentrations were also examined. RESULTS Short-term treatment with V-PYRRO/NO releasing NO selectively in the liver improved liver perfusion and portal vein blood flow. This effect was associated with a slight improvement in glucose tolerance but there was no effect on liver steatosis, body weight, white adipose tissue mass, plasma lipid profile, or aminotransferase activity. CONCLUSION Short-term treatment with V-PYRRO/NO-derived NO improves perfusion in hepatic microcirculation and this effect may also contribute to the anti-steatotic effects of hepatoselective NO donors linked previously to the modulation of glucose and lipid metabolism in the liver.
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Affiliation(s)
- Edyta Kus
- Jagiellonian Centre for Experimental Therapeutics (JCET), Jagiellonian University, Kraków, Poland.
| | - Krzysztof Jasiński
- Department of MRI, Institute of Nuclear Physics Polish Academy of Sciences, Kraków, Poland.
| | - Tomasz Skórka
- Department of MRI, Institute of Nuclear Physics Polish Academy of Sciences, Kraków, Poland.
| | - Izabela Czyzynska-Cichon
- Jagiellonian Centre for Experimental Therapeutics (JCET), Jagiellonian University, Kraków, Poland.
| | - Stefan Chlopicki
- Jagiellonian Centre for Experimental Therapeutics (JCET), Jagiellonian University, Kraków, Poland; Chair of Pharmacology, Jagiellonian University Medical College, Kraków, Poland.
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Plumbagin Alleviates Capillarization of Hepatic Sinusoids In Vitro by Downregulating ET-1, VEGF, LN, and Type IV Collagen. BIOMED RESEARCH INTERNATIONAL 2017; 2017:5603216. [PMID: 28770223 PMCID: PMC5523349 DOI: 10.1155/2017/5603216] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/28/2017] [Revised: 05/28/2017] [Accepted: 06/05/2017] [Indexed: 12/19/2022]
Abstract
Critical roles for liver sinusoidal endothelial cells (LSECs) in liver fibrosis have been demonstrated, while little is known regarding the underlying molecular mechanisms of drugs delivered to the LSECs. Our previous study revealed that plumbagin plays an antifibrotic role in liver fibrosis. In this study, we investigated whether plumbagin alleviates capillarization of hepatic sinusoids by downregulating endothelin-1 (ET-1), vascular endothelial growth factor (VEGF), laminin (LN), and type IV collagen on leptin-stimulated LSECs. We found that normal LSECs had mostly open fenestrae and no organized basement membrane. Leptin-stimulated LSECs showed the formation of a continuous basement membrane with few open fenestrae, which were the features of capillarization. Expression of ET-1, VEGF, LN, and type IV collagen was enhanced in leptin-stimulated LSECs. Plumbagin was used to treat leptin-stimulated LSECs. The sizes and numbers of open fenestrae were markedly decreased, and no basement membrane production was found after plumbagin administration. Plumbagin decreased the levels of ET-1, VEGF, LN, and type IV collagen in leptin-stimulated LSECs. Plumbagin promoted downregulation of ET-1, VEGF, LN, and type IV collagen mRNA. Altogether, our data reveal that plumbagin reverses capillarization of hepatic sinusoids by downregulation of ET-1, VEGF, LN, and type IV collagen.
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Gaddam RR, Fraser R, Badiei A, Chambers S, Cogger VC, Le Couteur DG, Bhatia M. Differential Effects of Kupffer Cell Inactivation on Inflammation and The Liver Sieve Following Caecal-Ligation and Puncture-Induced Sepsis in Mice. Shock 2017; 47:480-490. [PMID: 27648694 DOI: 10.1097/shk.0000000000000755] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Sepsis remains a common clinical problem with significant mortality. Activation of the Kupffer cells during sepsis is associated with systemic inflammatory response and multiple organ failure. Kupffer cell activation also leads to structural changes in the liver sinusoidal endothelial cells (LSECs) during endotoxemia. However, these effects remain to be elucidated in caecal-ligation and puncture (CLP)-induced polymicrobial sepsis. To investigate the role of Kupffer cells on LSECs fenestrae and inflammation during CLP-induced sepsis, sepsis was induced by CLP and mice were treated with gadolinium chloride (GdCl3) before CLP-induced sepsis, to inactivate Kupffer cells. Mice were sacrificed after 8 h. Blood, liver, and lung tissues were collected and processed to measure LSECs fenestration, myeloperoxidase (MPO) activity, alanine transaminase (ALT) and aspartate aminotransferase (AST) activity, histological examination, and various cytokines/chemokines levels. LSECs fenestrae was studied using scanning electron micrographs of the LSECs. Strikingly, CLP mice treated with GdCl3 were protected against liver injury as evidenced by decreased LSECs defenestration and damage, MPO, ALT and AST activities, liver tissue damage, and inflammatory cytokines TNF-α, IL-6 and IL-1β, and chemokines MCP-1 and MIP-2α. However, CLP mice treated with GdCl3 had no protection against increased lung MPO activity, tissue damage, inflammatory cytokines, and chemokines. Treatment with GdCl3 also had no effect on the systemic inflammatory response as shown by no change in the circulatory inflammatory cytokines and chemokines following CLP-induced sepsis. Collectively, these data suggest that inactivation of Kupffer cells by GdCl3 protects the liver but had no effect on lung injury or inflammation and systemic inflammatory response following CLP-induced sepsis.
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Affiliation(s)
- Ravinder Reddy Gaddam
- *Department of Pathology, University of Otago, Christchurch, New Zealand †Centre for Education and Research on Ageing, Ageing and Alzheimers Institute and the ANZAC Research Institute, University of Sydney and Concord Hospital, Sydney, Australia
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Gaddam RR, Fraser R, Badiei A, Chambers S, Cogger VC, Le Couteur DG, Ishii I, Bhatia M. Cystathionine-Gamma-Lyase Gene Deletion Protects Mice against Inflammation and Liver Sieve Injury following Polymicrobial Sepsis. PLoS One 2016; 11:e0160521. [PMID: 27518439 PMCID: PMC4982653 DOI: 10.1371/journal.pone.0160521] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2016] [Accepted: 07/19/2016] [Indexed: 01/13/2023] Open
Abstract
BACKGROUND Hydrogen sulfide (H2S), produced by the activity of cystathionine-gamma-lyase (CSE), is a key mediator of inflammation in sepsis. The liver sinusoidal endothelial cells (LSECs) are important target and mediator of sepsis. The aim of this study was to investigate the role of CSE-derived H2S on inflammation and LSECs fenestrae in caecal-ligation and puncture (CLP)-induced sepsis using CSE KO mice. METHODS Sepsis was induced by CLP, and mice (C57BL/6J, male) were sacrificed after 8 hours. Liver, lung, and blood were collected and processed to measure CSE expression, H2S synthesis, MPO activity, NF-κB p65, ERK1/2, and cytokines/chemokines levels. Diameter, frequency, porosity and gap area of the liver sieve were calculated from scanning electron micrographs of the LSECs. RESULTS An increased CSE expression and H2S synthesizing activity in the liver and lung of wild-type mice following CLP-induced sepsis. This was associated with an increased liver and lung MPO activity, and increased liver and lung and plasma levels of the pro-inflammatory cytokines TNF-α, IL-6, and IL-1β, and the chemokines MCP-1 and MIP-2α. Conversely, CSE KO mice had less liver and lung injury and reduced inflammation following CLP-induced sepsis as evidenced by decreased levels of H2S synthesizing activity, MPO activity, and pro-inflammatory cytokines/chemokines production. Extracellular-regulated kinase (ERK1/2) and nuclear factor-κB p65 (NF-κB) became significantly activated after the CLP in WT mice but not in CSE KO mice. In addition, CLP-induced damage to the LSECs, as indicated by increased defenestration and gaps formation in the LSECs compared to WT sham control. CSE KO mice showed decreased defenestration and gaps formation following sepsis. CONCLUSIONS Mice with CSE (an H2S synthesising enzyme) gene deletion are less susceptible to CLP-induced sepsis and associated inflammatory response through ERK1/2-NF-κB p65 pathway as evidenced by reduced inflammation, tissue damage, and LSECs defenestration and gaps formation.
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Affiliation(s)
| | - Robin Fraser
- Department of Pathology, University of Otago, Christchurch, New Zealand
| | - Alireza Badiei
- Department of Pathology, University of Otago, Christchurch, New Zealand
| | - Stephen Chambers
- Department of Pathology, University of Otago, Christchurch, New Zealand
| | - Victoria C Cogger
- Centre for Education and Research on Ageing, Alzheimers and Ageing Institute, Biogerentology, ANZAC Research Institute, University of Sydney, Sydney and Concord Hospital, Sydney, Australia
| | - David G Le Couteur
- Centre for Education and Research on Ageing, Alzheimers and Ageing Institute, Biogerentology, ANZAC Research Institute, University of Sydney, Sydney and Concord Hospital, Sydney, Australia
| | - Isao Ishii
- Department of Biochemistry, Graduate School of Pharmaceutical Sciences, Keio University, Tokyo, Japan
| | - Madhav Bhatia
- Department of Pathology, University of Otago, Christchurch, New Zealand
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Boye A, Zou YH, Yang Y. Metabolic derivatives of alcohol and the molecular culprits of fibro-hepatocarcinogenesis: Allies or enemies? World J Gastroenterol 2016; 22:50-71. [PMID: 26755860 PMCID: PMC4698508 DOI: 10.3748/wjg.v22.i1.50] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/28/2015] [Revised: 10/12/2015] [Accepted: 11/19/2015] [Indexed: 02/06/2023] Open
Abstract
Chronic intake of alcohol undoubtedly overwhelms the structural and functional capacity of the liver by initiating complex pathological events characterized by steatosis, steatohepatitis, hepatic fibrosis and cirrhosis. Subsequently, these initial pathological events are sustained and ushered into a more complex and progressive liver disease, increasing the risk of fibro-hepatocarcinogenesis. These coordinated pathological events mainly result from buildup of toxic metabolic derivatives of alcohol including but not limited to acetaldehyde (AA), malondialdehyde (MDA), CYP2E1-generated reactive oxygen species, alcohol-induced gut-derived lipopolysaccharide, AA/MDA protein and DNA adducts. The metabolic derivatives of alcohol together with other comorbidity factors, including hepatitis B and C viral infections, dysregulated iron metabolism, abuse of antibiotics, schistosomiasis, toxic drug metabolites, autoimmune disease and other non-specific factors, have been shown to underlie liver diseases. In view of the multiple etiology of liver diseases, attempts to delineate the mechanism by which each etiological factor causes liver disease has always proved cumbersome if not impossible. In the case of alcoholic liver disease (ALD), it is even more cumbersome and complicated as a result of the many toxic metabolic derivatives of alcohol with their varying liver-specific toxicities. In spite of all these hurdles, researchers and experts in hepatology have strived to expand knowledge and scientific discourse, particularly on ALD and its associated complications through the medium of scientific research, reviews and commentaries. Nonetheless, the molecular mechanisms underpinning ALD, particularly those underlying toxic effects of metabolic derivatives of alcohol on parenchymal and non-parenchymal hepatic cells leading to increased risk of alcohol-induced fibro-hepatocarcinogenesis, are still incompletely elucidated. In this review, we examined published scientific findings on how alcohol and its metabolic derivatives mount cellular attack on each hepatic cell and the underlying molecular mechanisms leading to disruption of core hepatic homeostatic functions which probably set the stage for the initiation and progression of ALD to fibro-hepatocarcinogenesis. We also brought to sharp focus, the complex and integrative role of transforming growth factor beta/small mothers against decapentaplegic/plasminogen activator inhibitor-1 and the mitogen activated protein kinase signaling nexus as well as their cross-signaling with toll-like receptor-mediated gut-dependent signaling pathways implicated in ALD and fibro-hepatocarcinogenesis. Looking into the future, it is hoped that these deliberations may stimulate new research directions on this topic and shape not only therapeutic approaches but also models for studying ALD and fibro-hepatocarcinogenesis.
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Tekkesin N, Taga Y, Sav A, Bozkurt S. Modulation of extracellular matrix proteins and hepatate stellate cell activation following gadolinium chloride induced Kuffer cell blockade in an experimental model of liver fibrosis/cirrhosis. QSCIENCE CONNECT 2013. [DOI: 10.5339/connect.2013.17] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022] Open
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Fan JH, Feng GG, Huang L, Tsunekawa K, Honda T, Katano Y, Hirooka Y, Goto H, Kandatsu N, Ando K, Fujiwara Y, Koide T, Okada S, Ishikawa N. Role of naofen in apoptosis of hepatocytes induced by lipopolysaccharide through mitochondrial signaling in rats. Hepatol Res 2012; 42:696-705. [PMID: 22409254 DOI: 10.1111/j.1872-034x.2012.00972.x] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
AIM Lipopolysaccharide (LPS) causes apoptosis of hepatocytes, which is probably mediated by inflammatory substances released from Kupffer cells (KCs). Recently, we have reported that naofen, a newly found intracellular WD40-repeat protein, has a role in inducing the apoptosis in HEK293 cells. Hence, the present study was undertaken to investigate a role of naofen in the LPS-induced apoptosis of rat hepatocytes. METHODS Rats were treated with i.v. injections of LPS, and livers were extirpated to evaluate expression of naofen and apoptosis. In in vitro experiments, hepatocytes and KCs were separately isolated from rat livers. The incubation medium for KCs treated with LPS (KC-CM) was used for hepatocyte culture. RESULTS Intravenous injections of LPS enhanced the expression of naofen in the livers. Livers showed terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL)-positive staining, and elevated caspase-3 activity. In isolated KCs or hepatocytes, LPS hardly affected naofen expression and caspase-3 activity, whereas incubation of hepatocytes with KC-CM enhanced both naofen expression and caspase-3 activation. Transfection of hepatocyte with naofen siRNA prevented such effects of KC-CM, and clearly eliminated KC-CM-induced reduction of Bcl-2 and Bcl-xL. In contrast, overexpression of naofen in hepatocytes downregulated Bcl-2 and Bcl-xL, released cytochrome c from mitochondria, and activated caspase-3. CONCLUSION These results indicate that LPS may induce the hepatic apoptosis in association with enhanced naofen expression, and that naofen may mediate the activation of caspase-3 through downregulating the Bcl-2 and Bcl-xL expression, and releasing cytochrome c from mitochondria to cytoplasm.
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Affiliation(s)
- Jun-Hua Fan
- Department of Gastroenterology, Nagoya University Graduate School of Medicine, Nagoya, Departments of Pharmacology Anesthesiology, Aichi Medical University School of Medicine, Nagakute Health Research Center, Aichi Gakuin University, Nisshin, Aichi Prefecture, Japan
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Toll-like receptors in the pathogenesis of alcoholic liver disease. Gastroenterol Res Pract 2010; 2010. [PMID: 20827314 PMCID: PMC2933900 DOI: 10.1155/2010/710381] [Citation(s) in RCA: 79] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/20/2010] [Accepted: 07/20/2010] [Indexed: 12/15/2022] Open
Abstract
In the multifactorial pathophysiology of alcoholic liver disease (ALD), inflammatory cascade activation plays a central role. Recent studies demonstrated that Toll-like Receptors, the sensors of microbial and endogenous danger signals, are expressed and activated in innate immune cells as well as in parenchymal cells in the liver and thereby contribute to ALD. In this paper, we discuss the importance of gut-derived endotoxin and its recognition by TLR4. The significance of TLR-induced intracellular signaling pathways and cytokine production as well as the contribution of reactive oxygen radicals is evaluated. The contribution of TLR signaling to induction of liver fibrosis and hepatocellular cancer is reviewed in the context of alcohol-induced liver disease.
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Cheluvappa R, Denning GM, Lau GW, Grimm MC, Hilmer SN, Le Couteur DG. Pathogenesis of the hyperlipidemia of Gram-negative bacterial sepsis may involve pathomorphological changes in liver sinusoidal endothelial cells. Int J Infect Dis 2010; 14:e857-67. [PMID: 20609608 DOI: 10.1016/j.ijid.2010.02.2263] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2009] [Revised: 11/30/2009] [Accepted: 02/25/2010] [Indexed: 12/11/2022] Open
Abstract
The Gram-negative bacterium Pseudomonas aeruginosa is one of the most common opportunistic pathogens, especially after liver transplantation. Pathophysiological alterations of liver sinusoidal endothelial cells (LSECs) have far-reaching repercussions on the liver and on metabolism. LSECs are perforated with fenestrations, pores that facilitate the transfer of lipoproteins and macromolecules between blood and hepatocytes. Gram-negative bacterial endotoxin (lipopolysaccharide, LPS) and the P. aeruginosa toxin, pyocyanin, have marked effects on LSECs. Initial loss of LSEC porosity (defenestration) induced by P. aeruginosa pyocyanin and LPS may confer subsequent immune tolerance to circulating bacterial antigens and toxins. This review collates the known immune responses of the liver to Gram-negative bacterial toxins, with a focus on LSECs. Hyperlipidemia is an important response to Gram-negative bacterial sepsis. The mechanisms proposed for sepsis-associated hyperlipidemia include tissue lipoprotein lipase inhibition and upregulated hepatic triglyceride production. In this review, we propose defenestration of the LSECs by bacterial toxins as an additional mechanism for the hyperlipidemia of sepsis. Given the role of LSECs in hyperlipidemia and liver allograft rejection, LSEC changes induced by P. aeruginosa toxins including LPS and pyocyanin may have significant clinical implications.
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Affiliation(s)
- Rajkumar Cheluvappa
- Department of Medicine, St. George Clinical School and Centre for Infection and Inflammation Research, School of Medical Sciences, Wallace Wurth Building, University of New South Wales, Gate 9 High Street, Sydney, NSW 2052, Australia.
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Cheluvappa R, Denning GM, Lau GW, Grimm MC, Hilmer SN, Le Couteur DG. Pseudomonas aeruginosa and the hyperlipidaemia of sepsis. Pathology 2009; 41:615-21. [DOI: 10.3109/00313020903257764] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
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He Y, Sadahiro T, Noh SI, Wang H, Todo T, Chai NN, Klein AS, Wu GD. Flow cytometric isolation and phenotypic characterization of two subsets of ED2(+) (CD163) hepatic macrophages in rats. Hepatol Res 2009; 39:1208-18. [PMID: 19624775 DOI: 10.1111/j.1872-034x.2009.00528.x] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
AIMS Macrophages in the liver are well known for their functional heterogeneity. However, subpopulations of the hepatic macrophages are not well defined. METHODS Two subsets of hepatic macrophages isolated from rats via FACS with immunolabeling of ED2 (anti-CD163) antibody were studied for phenotypic and functional characteristics. RESULTS A subset showed an ED2(high) and autofluorescence(high) (ED2(high)/AF(high)) phenotype, exhibiting characteristics consistent with the description of the Kupffer cells (KC). A second subset, displaying an ED2(dim)/AF(dim) phenotype, was smaller in size, monocyte-like and weak in phagocytosis. Transmission electron microscopy demonstrated that both subsets are phagocytes. Quantitative RT-PCR revealed that in addition to expression of macrophage-related surface markers such as CD14, ED1 (CD68), fucose receptor, and CD163, the ED2(dim)/ AF(dim) cells expressed mRNA encoding for myeloid lineage differentiation markers ERMP12 (PECAM) and ERMP20 (Ly-6C). These two subsets exhibited differential in gene expression of selected cytokines, extracellular matrix proteinases, and Toll-like receptor in normal livers, as well as significantly upregulated expression in cholestatic livers induced by bile duct ligation. CONCLUSION The data suggest that the ED2(high)/AF(high) population of the liver cells represent the conventional Kupffer cells. The ED2(dim)/AF(dim) cells, however, are small hepatic resident macrophages characteristically different from the conventional Kupffer cells.
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Affiliation(s)
- Yao He
- Comprehensive Transplant Center, Department of Surgery, Cedars-Sinai Medical Center, Los Angeles, California, USA
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Yang ZX, Han DW, Xing HY, Liu HR, Yan Z. Pathogenesis of hepatic sinusoidal capillarization in hepatic cirrhosis. Shijie Huaren Xiaohua Zazhi 2009; 17:3101-3108. [DOI: 10.11569/wcjd.v17.i30.3101] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
AIM: To investigate the role of intestinal endotoxemia in the pathogenesis of hepatic sinusoidal capillarization in hepatic cirrhosis and explore possible mechanisms involved.
METHODS: Forty male Wistar rats were randomly divided into two groups: control group (n = 8) and experimental group (n= 32). Hepatic cirrhosis was induced in rats using carbon tetrachloride (CCl4) and alcohol. Rats in the experimental group were killed at weeks 2, 4, 6 and 8, respectively, while those in the control group were executed at the beginning of the experiment. The portal venous pressure (PVP) was measured by cranial mesenteric vein cannulation. The degree of hepatic cirrhosis was evaluated by hematoxylin and eosin (HE) staining and Van Gieson's (VG) staining. The expression of alpha-smooth muscle actin (α-SMA), laminin (LN) and transforming growth factor-β1 (TGF-β1) in the liver was detected by immunohistochemistry. The dynamic changes in the levels of endotoxin, alanine transferase (ALT) and tumor necrosis factor-α (TNF-α) in plasma were monitored using various kits. The defenestration of liver sinusoidal endothelial cells (LSECs) was observed using a scanning electron microscope.
RESULTS: In the experimental group, plasma ALT level reached its peak at week 2 (57.84 ± 7.57 IU/L) and thereafter decreased. Plasma endotoxemia level gradually increased from week 2 to 6, but slightly decreased at week 8. Plasma TNF-α level increased from week 2 to 4, slightly decreased at week 6, and increased again at week 8. At all time points, the values of the above parameters were significant higher in the experimental group than in the control group (all P < 0.05). PVP showed the same tendency as TNF-α level, increasing from week 2 to 4, slightly decreasing at week 6, and increasing again at week 8. LSEC fenestration gradually shrank, lessened and disappeared from week 0 to 8. The expression levels of LN and TGF-β1 increased from week 0 to 8, significantly higher than those in the control group or at the previous time points in the same group (all P < 0.05). The expression level of α-SMA increased from week 0 to 6, but slightly decreased at week 8.
CONCLUSION: Intestinal endotoxemia occurs in hepatic cirrhosis rats, which can increase the synthesis of TNF-α, TGF-β1 and LN and promote LSEC defenestration. Intestinal endotoxemia may be indirectly involved in the development of hepatic sinusoidal capillarization.
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Katsargyris A, Klonaris C, Alexandrou A, Giakoustidis AE, Vasileiou I, Theocharis S. Toll-like receptors in liver ischemia reperfusion injury: a novel target for therapeutic modulation? Expert Opin Ther Targets 2009; 13:427-42. [PMID: 19335065 DOI: 10.1517/14728220902794939] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
BACKGROUND There is increasing evidence that Toll-like receptors (TLRs) sense host tissue damage by engaging with endogenous ligands. TLRs are considered to be involved in many primarily non-immune-related diseases. Hepatic ischemia reperfusion injury (IRI) represents one of these disorders. OBJECTIVE To present the latest findings supporting the involvement of TLRs in liver IRI and to explore their role as potential targets for therapeutic intervention. METHODS A review of the literature summarizing the latest advances in TLR signaling, the role of TLRs in each hepatic cell population and the involvement of TLRs in the pathophysiology of hepatic IRI. The potential role of TLR-targeting treatment strategies in liver IRI is discussed. CONCLUSIONS Recent experimental evidence suggests that TLR activation on Kupffer cells provides the triggering signal for pro-inflammatory responses that lead to liver IRI. Modulating TLR signaling could have a beneficial effect in patients with liver IRI.
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Hou X, Zhou R, Wei H, Sun R, Tian Z. NKG2D-retinoic acid early inducible-1 recognition between natural killer cells and Kupffer cells in a novel murine natural killer cell-dependent fulminant hepatitis. Hepatology 2009; 49:940-9. [PMID: 19177594 DOI: 10.1002/hep.22725] [Citation(s) in RCA: 88] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
Abstract
UNLABELLED Increasing evidence suggests the contribution of natural killer (NK) cells to pathogenesis of human hepatitis, but the detailed mechanisms have yet to be clearly elucidated. In this study, injection of polyinosinic:polycytidylic acid (poly I:C) and D-galactosamine (D-GalN) was used to establish a novel murine fulminant hepatitis model: results showed that predepletion of either NK cells or Kupffer cells could completely abolish the liver injury. Injection of poly I:C/D-GalN into mice could promote tumor necrosis factor-alpha production and surface retinoic acid early inducible-1 (Rae1) protein expression by Kupffer cells, which then activated NK cells to produce interferon-gamma via NKG2D-Rae1 recognition. NK cell-derived interferon-gamma and Kupffer cell-derived tumor necrosis factor-alpha synergistically mediated the severe liver injury. Moreover, Kupffer cell-derived interleukin-12 and interleukin-18 were also found to improve cross talk between NK cells and Kupffer cells. CONCLUSION These results provide the first in vivo evidence that NKG2D/ligand interaction is involved in the synergic effects of NK cells and Kupffer cells on acute liver injury.
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Affiliation(s)
- Xin Hou
- Institute of Immunology, Hefei National Laboratory for Physical Sciences at Microscale and School of Life Sciences, University of Science and Technology of China, Hefei, China
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19
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Abstract
Toll-like receptors (TLRs) are pattern recognition receptors that recognize pathogen-associated molecular patterns and signal through adaptor molecules, myeloid differentiation factor 88 (MyD88), Toll/IL-1 receptor domain containing adaptor protein (TIRAP), Toll/IL-1 receptor domain containing adaptor inducing interferon-beta (TRIF), and TRIF-related adaptor molecule (TRAM) to activate transcription factors, nuclear factor (NF)-kappaB, activator protein 1 (AP-1), and interferon regulatory factors (IRFs) leading to the initiation of innate immunity. This system promptly initiates host defenses against invading microorganisms. Endogenous TLR ligands such as the products from dying cells may also engage with TLRs as damage-associated molecular patterns. Although Kupffer cells are considered the primary cells to respond to pathogen associated molecular patterns in the liver, recent studies provide evidence of TLR signaling in hepatic nonimmune cell populations, including hepatocytes, biliary epithelial cells, endothelial cells, and hepatic stellate cells. This review highlights advances in TLR signaling in the liver, the role of TLRs in the individual hepatic cell populations, and the implication of TLR signaling in acute and chronic liver diseases. We further discuss recent advances regarding cytosolic pattern recognition receptors, RNA helicases that represents a new concept in chronic hepatitis C virus infection.
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Affiliation(s)
- Ekihiro Seki
- Department of Medicine, University of California, San Diego, School of Medicine, La Jolla, CA 92093, USA.
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Lee CH, Loureiro-Silva MR, Abraldes JG, Iwakiri Y, Haq O, Groszmann RJ. Decreased intrahepatic response to alpha(1)-adrenergic agonists in lipopolysaccharide-treated rats is located in the sinusoidal area and depends on Kupffer cell function. J Gastroenterol Hepatol 2007; 22:893-900. [PMID: 17498219 DOI: 10.1111/j.1440-1746.2007.04922.x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/09/2022]
Abstract
BACKGROUND AND AIM Livers from lipopolysaccharide-treated rats have a decreased vascular response to alpha(1)-adrenergic agonists due to an increased production of nitric oxide. Kupffer cells play a central role in the development of intrahepatic microvascular abnormalities during endotoxemia. We investigated the role of Kupffer cells in the intrahepatic vascular tone control in normal and endotoxemic rats. METHOD Twenty-four hours after pretreatment with gadolinium chloride (to eliminate/inactivate Kupffer cells) or saline, rats were treated with lipopolysaccharide or a second dose of saline. Six hours later, rats (under deep anesthesia) were submitted to liver perfusion with Krebs-Henseleit solution using a system that allowed the measurement of both perfusion and sinusoidal pressures. Dose-response curves to methoxamine (alpha(1)-adrenergic agonist) were obtained in the absence or the presence of the nitric oxide synthase inhibitor N-monomethyl-L-arginine. RESULTS Pretreatment with gadolinium did not change the intrahepatic vascular response to methoxamine in normal livers. Livers from lipopolysaccharide-treated rats showed a decreased sinusoidal vascular response to methoxamine and a 10-fold increase in nitric oxide production during liver perfusion. Either pretreatment with gadolinium or the presence of N-monomethyl-L-arginine in the perfusate restored the response to methoxamine and decreased the nitric oxide overproduction by more than 50%. CONCLUSIONS Kupffer cells neither mediate nor modulate the intrahepatic vascular response to alpha(1)-adrenergic agonists in normal livers. Reduction in intrahepatic vascular response to alpha(1)-adrenergic agonists in livers from lipopolysaccharide-treated rats is located in the sinusoidal area and depends on Kupffer cell function.
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Affiliation(s)
- Chang-Hyeong Lee
- Hepatic Hemodynamic Laboratory, VA Medical Center, West Haven, Connecticut 06516, USA
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Eugenín EA, González HE, Sánchez HA, Brañes MC, Sáez JC. Inflammatory conditions induce gap junctional communication between rat Kupffer cells both in vivo and in vitro. Cell Immunol 2007; 247:103-10. [PMID: 17900549 PMCID: PMC2105790 DOI: 10.1016/j.cellimm.2007.08.001] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2007] [Revised: 08/01/2007] [Accepted: 08/02/2007] [Indexed: 01/16/2023]
Abstract
Connexin43 (Cx43), a gap junction protein subunit, has been previously detected in Kupffer cells (KCs) during liver inflammation, however, KCs phagocytose cell debris that may include Cx43 protein, which could explain the detection of Cx43 in KCs. We determined that KCs express Cx43 and form gap junctions (GJs) both in vivo and in vitro. In liver sections of animals treated with LPS, Cx43 was detected at ED2+ cells interfaces, indicating formation of GJs between KCs in vivo. In vitro, unstimulated KCs cultures did not form functional GJs, and expressed low levels of Cx43 that showed a diffuse intracellular distribution. In contrast, KCs treated with LPS plus IFN-gamma, expressed a greater amount of Cx43 at both, protein and mRNA levels, and showed Cx43 at cell-cell contacts associated with higher dye coupling. In conclusion, activation of KCs in vivo or in vitro resulted in enhanced Cx43 expression levels and formation of GJ that might play relevant roles during liver inflammation.
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Affiliation(s)
- Eliseo A Eugenín
- Department of Pathology, F727, 1300 Morris Park Ave, Albert Einstein College of Medicine, Bronx, NY, USA.
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Jahnke C, Mehrabi A, Golling M, Frankenberg MV, Kashfi A, Nentwich H, Fonouni H, Nickkholgh A, Schemmer P, Gutt CN, Weitz J, Schmidt J, Gebhard MM, Büchler MW, Kraus T. Evaluation of microperfusion disturbances in the transplanted liver after Kupffer cell destruction using GdCl3: an experimental porcine study. Transplant Proc 2006; 38:1588-1595. [PMID: 16797363 DOI: 10.1016/j.transproceed.2006.02.067] [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] [Received: 02/19/2005] [Indexed: 01/12/2023]
Abstract
BACKGROUND Organ function after liver transplantation is determined by ischemia-reperfusion injury. Destruction of Kupffer cells with gadolinium chloride (GdCl3) has been shown to have a possible preventive effect on the extent of this injury, which can be extrapolated by analyzing the distribution of hepatic microperfusion. The aim of this study was to evaluate the protective effect of GdCl3 on disturbances of microperfusion in the transplanted liver. METHODS Landrace pigs were randomly divided into three groups. In the control group (CG; n=6) a mapping of the native liver was conducted. For mapping, the four hepatic liver lobes were named from right to left with A to D and every lobe was divided into three vertical segments (cranial, medial, and caudal). In each of these 12 areas, microperfusion was quantified using a thermodiffusion probe (TD [mL/100 g/min]). The other two groups were considered as transplanted treated group (TTG; n=10) and transplanted nontreated group (TnTG; n=10). The TTG received an infusion of 20 mg/kg GdCl3 intravenously 24 hours before organ harvesting. Then standardized orthotopic liver transplantation was performed. In TnTG, standardized orthotopic liver transplantation was carried out without prior GdCl3 injection. In the recipients, the microperfusion of transplanted livers were mapped in both TnTG and TTG, in two different time points (1 hour [n=5] and 24 hours (n=5]) after reperfusion. RESULTS A significant reduction of macrophages in the TTG livers in comparison to the CG and TnTG livers was observed (P<.05). However, the number of macrophages in CG and TnTG livers showed no significant difference (P>.05). Regarding liver microperfusion, in TnTG, a marked heterogeneity was detected in the livers after reperfusion. Significant differences between liver lobes (horizontal planes; P=.032) and vertical layers of intralobar liver parenchyma (P=.029) were observed. The same pattern was seen in TTG livers after reperfusion and a significant difference between horizontal (P=.024) and vertical layers (P=.018) of liver tissue were observed. Comparing intralobar regional flow data between vertical planes 24 hours after reperfusion still showed a prominent variation of hepatic tissue perfusion in TnTG livers (P=.028). Within the same horizontal layers, no significant differences between lobes were measured anymore (P=.16). Contrary to TnTG, in TTG, a homogenous pattern of regional liver tissue perfusion was recorded 24 hours after reperfusion. Comparison of TD data on the liver regions showed no significant microperfusion differences in either horizontal (P=.888) or vertical (P=.841) layers. CONCLUSIONS Application of GdCl3 resulted in a significant reduction of Kupffer cells. Twenty four hours after transplantation microperfusion showed a homogeneous pattern, which constituted an earlier and better recovery of the transplanted liver. Therefore, destruction of Kupffer cells reduced ischemia-reperfusion injury and seemed to be responsible for the early recovery of microperfusion disturbances and thus for an improvement of graft function.
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Affiliation(s)
- C Jahnke
- Department of General, Visceral and Transplantation Surgery, University of Heidelberg, Heidelberg, Germany
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Sun D, Chen D, Du B, Pan J. Heat shock response inhibits NF-kappaB activation and cytokine production in murine Kupffer cells. J Surg Res 2005; 129:114-21. [PMID: 16243048 DOI: 10.1016/j.jss.2005.05.028] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2005] [Revised: 05/21/2005] [Accepted: 05/31/2005] [Indexed: 12/21/2022]
Abstract
BACKGROUND Kupffer cells play a crucial role in the pathogenesis of sepsis through production of proinflammatory mediators and control of systemic endotoxemia. The anti-inflammatory effects of heat shock response (HSP) have been well documented. However, the role of HSP in lipopolysaccharide (LPS) induced Kupffer cell activation has not been fully investigated. In this study, we investigated the effects of HSP on LPS induced Kupffer cell NF-kappaB activation and cytokine production. MATERIALS AND METHODS Kupffer cells were isolated from mice by collagenase digestion and HSP was induced by culturing Kupffer cells with sodium arsenite. Kupffer cells were stimulated in vitro by LPS. Heat shock protein (HSP)-70 expression and cytoplasmic IkappaBalpha protein was determined by Western blot. Supernatant tumor necrosis factor (TNF)-alpha, interleukin (IL)-6 and IL-10 levels were measured by ELISA. NF-kappaB activation was analyzed by electrophoresis mobility shift assay. Cytokine and IkappaBalpha mRNA expression were determined by RT-PCR. Toll-like receptor 4 expression on Kupffer cells was determined by flow cytometry. RESULTS HSP pre-conditioning significantly inhibited LPS-induced cytokine TNF-alpha and IL-6 production and mRNA expression. NF-kappaB activation and IkappaBalpha degradation induced by LPS were attenuated by HSP. HSP up-regulated expression of IkappaBalpha mRNA. No effect of HSP on cell surface expression of TLR4 was observed. CONCLUSIONS Increased IkappaBalpha stability and up-regulation of IkappaBalpha gene expression may be one of the mechanisms of the inhibition of LPS induced Kupffer cell activation by HSP. HSP also inhibited expression of the anti-inflammatory cytokine IL-10, and the mechanism and biological significance of this effect merit further investigation.
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Affiliation(s)
- Dongxu Sun
- Department of Critical Care Medicine, Peking Union Medical College Hospital, Peking Union Medical College & Chinese Academy of Medical Science, Beijing, PR China.
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Frankenberg MV, Weimann J, Fritz S, Fiedler J, Mehrabi A, Büchler MW, Kraus TW. Gadolinium chloride-induced improvement of postischemic hepatic perfusion after warm ischemia is associated with reduced hepatic endothelin secretion. Transpl Int 2005; 18:429-36. [PMID: 15773963 DOI: 10.1111/j.1432-2277.2004.00058.x] [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: 12/13/2022]
Abstract
Selective Kupffer cell blockade by gadolinium chloride (GdCl(3)) pretreatment of liver donors previously proved to be effective in reducing ischemia/reperfusion injury in rat liver transplants. Physiological mechanisms of this effect have not been specified so far. Vasoactive peptides are involved in liver blood flow regulation. We tested the hypothesis, that hepatic hemodynamic effects of GdCl(3) pretreatment are mediated by intrahepatic endothelin-1 (ET) secretion in a standardized porcine model of warm liver ischemia and reperfusion. Standardized warm hepatic ischemia (45 min) was induced after laparotomy in intubation narcoses (ITN) by Pringle-maneuver in pigs (n = 12). Animals were either pretreated with GdCl(3) (20 mg/kg i.v.) or sodium chloride 0.9% (control group) in a randomized manner 24 h before investigation. Relaparotomy was performed at day 7. Before, during ischemia and until 6 h after liver reperfusion, transhepatic blood flow (portal venous + hepatic artery flow) was defined by ultrasonic flow probes and hepatic parenchymous microcirculation evaluated by implanted thermodiffusion electrodes. ET plasma concentrations were analyzed (commercial RIA) at all time points in the hepatic veins after selective canulation. GdCl(3) pretreatment of animals markedly improved hepatic macro- and microperfusion before and particularly after warm ischemia. Mean ET plasma concentrations in the hepatic vein were significantly lower before, 6 h and 7 days after ischemia, compared with controls. Kupffer cell destruction by GdCl(3) pretreatment improves hepatic micro- and macroperfusion after warm ischemia, thus indicating reduced ischemia/reperfusion injury. Documented reduction of postischemic liver blood flow impairment after GdCl(3) pretreatment could be mediated by a decreased hepatic ET secretion, as hemodynamic effects were associated with significantly reduced ET plasma levels in hepatic veins.
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Lee CM, Yeoh GC, Olynyk JK. Differential effects of gadolinium chloride on Kupffer cells in vivo and in vitro. Int J Biochem Cell Biol 2004; 36:481-8. [PMID: 14687926 DOI: 10.1016/j.biocel.2003.08.004] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Gadolinium chloride (GdCl) is commonly used to study the role of Kupffer cells in liver disease in vivo. The in vitro effects of GdCl on cultured Kupffer cells are poorly characterised. The aim of this study was to characterise rat Kupffer cell TNFalpha production, phagocytic function, and ED1 and ED2 antigen expression following the administration of GdCl. For in vivo experiments, rats received 10mg/kg GdCl IV or sterile saline. Lipopolysaccharide 3mg/kg IP (LPS) was administered 4h prior to sacrifice on Days 1-3, 5 or 8 following GdCl injection. Hepatic ED1 and ED2 positive macrophage numbers and TNFalpha mRNA levels were determined. For in vitro experiments, Kupffer cells were cultured in the presence of 0-270 microM GdCl for 24h following which viability, TNFalpha protein production in response to LPS (10 ng/ml), phagocytosis, and ED1 and ED2 staining were evaluated. In vivo, the proportion of ED1 positive cells which were ED2 positive was reduced from 87 to 3% and hepatic TNFalpha mRNA levels following LPS declined by 60% over Days 1-5 after injection of GdCl (P<0.01). In vitro, phagocytosis declined with increasing concentrations of GdCl. GdCl (0-27 microM) did not effect cultured Kupffer cell viability, TNFalpha production, ED1 or ED2 staining. We conclude that GdCl significantly reduces ED2 expression by Kupffer cells in vivo. In vitro, GdCl has a dose dependent effect on phagocytosis but only effects viability and TNFalpha production at high concentrations. ED2 expression of cultured Kupffer cells is not affected by GdCl.
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Affiliation(s)
- Clair M Lee
- School of Medicine and Pharmacology, University of Western Australia, Fremantle Hospital Campus, P.O. Box 480, Fremantle 6959, WA, Australia
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Nagaoka MR, Kouyoumdjian M, Borges DR. Hepatic clearance of tissue-type plasminogen activator and plasma kallikrein in experimental liver fibrosis. Liver Int 2003; 23:476-83. [PMID: 14986822 DOI: 10.1111/j.1478-3231.2003.00872.x] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/13/2023]
Abstract
UNLABELLED We have previously shown that tissue-type plasminogen activator (tPA) and rat plasma kallikrein (RPK) share a common, but not unique, pathway for liver clearance. AIM To evaluate the hepatic clearance of both proteases in experimental liver fibrosis. METHODS The hepatic clearance of these proteases was studied in porcine serum-induced liver fibrosis using the isolated and perfused rat liver model. To better interpret the results, we also studied four other experimental groups: the turpentine oil-induced acute-phase response (AP group), AP group followed by GdCl3 administration (AP/Gd group), CCl4-induced cirrhosis (CCl4 group) and normal group. RESULTS The tPA clearance decreased significantly by both fibrotic and cirrhotic rat livers whereas the RPK clearance was not altered by the fibrotic rat liver. The hepatic clearance of tPA was reduced in the AP and AP/Gd groups; on the other hand, RPK clearance was increased in the AP group and, interestingly, this effect was neutralized by concomitant GdCl3 administration. CONCLUSIONS We observed that tPA and RPK clearances were affected differently by fibrosis as well as by different stimuli of the acute-phase response, despite the fact that they share a common hepatic clearance mechanism in normal livers, and they were equally affected in cirrhosis.
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Affiliation(s)
- Marcia R Nagaoka
- Laboratory of Experimental Hepatology, Department of Biochemistry, Universidade Federal de São Paulo (UNIFESP), São Paulo, Brazil
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27
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Frankenberg M, Golling M, Mehrabi A, Nentwich H, Klar E, Kraus TW. Donor pretreatment with gadolinium chloride improves early graft function and survival after porcine liver transplantation. Transpl Int 2003. [DOI: 10.1111/j.1432-2277.2003.tb00245.x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
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Yamada T, Takahashi S, Masuda K, Ohara H, Nakazawa T, Sano H, Ando T, Nakamura S, Kobayashi S, Kuno A, Aoki S, Nomura T, Joh T, Itoh M. Kupffer-cell depletion attenuates colonic and extracolonic granulomatous inflammation in chronic colitis. ACTA ACUST UNITED AC 2003; 142:268-77. [PMID: 14625533 DOI: 10.1016/s0022-2143(03)00132-x] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
Abstract
Intramural injection of peptidoglycan-polysaccharide polymers into the distal colon in rats induces granulomatous colitis associated with extracolonic manifestations. We sought to clarify the effects of Kupffer-cell depletion induced by the intravenous administration of gadolinium on colonic and extracolonic inflammation in this model. The effects of Kupffer-cell depletion on acute and chronic inflammation were evaluated 3 days and 3 weeks after injection of peptidoglycan-polysaccharide, respectively. We assessed the effects of gadolinium on colonic cytokine levels in vivo and the viability of elicited peritoneal macrophages and peptidoglycan-polysaccharide-induced production of nitrite, an indirect index of nitric oxide production, by these cells in vitro. A single injection of gadolinium caused a marked decrease in the number of Kupffer cells stained with antibodies within 3 days. Gadolinium treatment did not alter acute inflammation at 3 days. Repeated treatment with gadolinium dramatically attenuated grossly observed chronic inflammation, including thickening of colon wall, hepatic and splenic nodules, and swelling of foot joints; and significantly reduced the proportional areas occupied by granulomas in the colon, liver, and spleen at 3 weeks. These protective effects were reflected in significant reduction in colon and liver weights; gross scores; colonic myeloperoxidase activity, an indirect quantitative index of granulocyte infiltration; colonic interleukin-1beta levels; plasma nitrite and nitrate levels; and decreased tendency toward arthritis. Although gadolinium did not cause injury in elicited peritoneal macrophages in vitro, the compound dose-dependently attenuated peptidoglycan-polysaccharide-induced production of nitrite by these cells. Chronic Kupffer-cell depletion attenuates peptidoglycan-polysaccharide-induced granulomatous inflammation in the colon, liver, and spleen and reduces the incidence of arthritis, possibly by suppressing the production of interleukin-1beta and nitric oxide.
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Affiliation(s)
- Tamaki Yamada
- Department of Comprehensive Medicine, Internal Medicine and Bioregulation, Nagoya City University Graduate School of Medical Sciences, Nagoya, Aichi, Japan.
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Pestel S, Nath A, Jungermann K, Schieferdecker HL. Inhibition of prostaglandin D2 clearance in rat hepatocytes by the thromboxane receptor antagonists daltroban and ifetroban and the thromboxane synthase inhibitor furegrelate. Biochem Pharmacol 2003; 66:643-52. [PMID: 12906929 DOI: 10.1016/s0006-2952(03)00398-8] [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: 10/27/2022]
Abstract
Prostanoids, i.e. prostaglandins and thromboxane, regulate liver-specific functions both in homeostasis and during defense reactions. For example, prostanoids are released from Kupffer cells, the resident liver macrophages, in response to the inflammatory mediator anaphylatoxin C5a, and mediate an enhanced glucose output from hepatocytes as energy supply. In perfused rat livers, the thromboxane receptor antagonist daltroban enhanced C5a-induced prostanoid overflow and reduced glucose output. It was the aim of this study to elucidate whether daltroban interfered with prostanoid release from Kupffer cells or prostanoid clearance by hepatocytes, and/or whether it directly influenced prostanoid-dependent glucose metabolism in these cells. In perfused rat livers, daltroban enhanced prostaglandin (PG)D(2) overflow not only after infusion of C5a (15-fold), but also after PGD(2) (10-fold). Neither daltroban nor another receptor antagonist, ifetroban, or the thromboxane synthase inhibitor furegrelate enhanced prostanoid release from Kupffer cells. In contrast, all inhibitors reduced clearance, i.e. uptake and degradation, of PGD(2) by hepatocytes: within 5 min uptake of 1 nmol/L PGD(2) was reduced from 43+/-5 fmol (controls) to 22+/-6 fmol (daltroban), 24+/-6 fmol (ifetroban) and 21+/-6 fmol (furegrelate). PGD(2) in the medium was reduced to 39+/-7% in the controls, but remained at 93+/-9%, 93+/-11% and 60+/-3% in the presence of the inhibitors. PGD(2)-dependent glucose output in the perfused liver or activation of glycogen phosphorylase in isolated hepatocytes remained unaffected by daltroban. These data clearly demonstrate that the thromboxane-inhibitors reduced PGD(2) clearance by hepatocytes, presumably by inhibition of prostanoid transport into the cells. In contrast, they did not interfere with PGD(2)-dependent glucose metabolism, suggesting an independent mechanism for the inhibition of glucose output from the liver.
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Affiliation(s)
- Sabine Pestel
- Institut für Biochemie und Molekulare Zellbiologie, Georg-August-Universität Göttingen, Humboldtallee 23, D-37073 Göttingen, Germany
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30
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Abstract
Shock liver describes a collecting pool of critically ill patients in whom the elevation of liver function tests or overt hepatic dysfunction is apparent. Different grades of shock liver affect about 50% of all intensive-care patients, varying from a mild elevation of serum aminotransferase and bilirubin levels in septic patients to an acute onset of high serum aminotransferases after haemodynamic shock. Abnormalities can subside within days or progressively deteriorate when persistent hepatic microcirculatory failure is present. Although hepatic injury in critically ill patients influences mortality rates it is underdiagnosed. The underlying pathophysiology involves changes in the portal and arterial blood supply as well as in microcirculation. Cross-talk between hepatocytes, Kupffer cells and endothelial cells, leading to an inflammatory response mediated primarily by tumour necrosis factor-alpha (TNF-alpha), is central to shock liver. The liver is a victim of shock inducers, and can also be the orchestrator of the inflammatory response syndrome (IRS). Hepatic injury by TNF-alpha is modulated by the prevalent pro-inflammatory or anti-inflammatory mediator profile elaborated by Kupffer cells. Kupffer cells additionally participate in the clearance of endotoxin, bacteria and inflammatory mediators and are thereby capable of preventing IRS. The hepatocyte undergoes dramatic alterations in synthetic activity, biliary transport, bile flow and glucose metabolism. Although standard determinations of aminotransferases, coagulation studies, glucose, lactate and bilirubin can detect hepatic injury they only partially reflect the cellular mechanisms driving shock liver. The management of shock liver is focused on the prevention of precipitating causes by controlling sepsis, circulation parameters and metabolism in addition to the cautious monitoring of therapeutic measures that can increase hepatic injury, which include intravenous nutrition, mechanical ventilation and catecholamine administration.
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Affiliation(s)
- Christian P Strassburg
- Department of Gastroenterology, Hepatology and Endocrinology, Hannover Medical School, Carl-Neuberg-Strasse 1, 30625 Hannover, Germany.
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31
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Hung DY, Chang P, Cheung K, Winterford C, Roberts MS. Quantitative evaluation of altered hepatic spaces and membrane transport in fibrotic rat liver. Hepatology 2002; 36:1180-9. [PMID: 12395328 DOI: 10.1053/jhep.2002.36820] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
Four animal models were used to quantitatively evaluate hepatic alterations in this study: (1) a carbon tetrachloride control group (phenobarbital treatment only), (2) a CCl(4)-treated group (phenobarbital with CCl(4) treatment), (3) an alcohol-treated group (liquid diet with alcohol treatment), and (4) a pair-fed alcohol control group (liquid diet only). At the end of induction, single-pass perfused livers were used to conduct multiple indicator dilution (MID) studies. Hepatic spaces (vascular space, extravascular albumin space, extravascular sucrose space, and cellular distribution volume) and water hepatocyte permeability/surface area product were estimated from nonlinear regression of outflow concentration versus time profile data. The hepatic extraction ratio of (3)H-taurocholate was determined by the nonparametric moments method. Livers were then dissected for histopathologic analyses (e.g., fibrosis index, number of fenestrae). In these 4 models, CCl(4)-treated rats were found to have the smallest vascular space, extravascular albumin space, (3)H-taurocholate extraction, and water hepatocyte permeability/surface area product but the largest extravascular sucrose space and cellular distribution volume. In addition, a linear relationship was found to exist between histopathologic analyses (fibrosis index or number of fenestrae) and hepatic spaces. The hepatic extraction ratio of (3)H-taurocholate and water hepatocyte permeability/surface area product also correlated to the severity of fibrosis as defined by the fibrosis index. In conclusion, the multiple indicator dilution data obtained from the in situ perfused rat liver can be directly related to histopathologic analyses.
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Affiliation(s)
- Daniel Y Hung
- Department of Medicine and Division of Chemical Pathology, University of Queensland, Princess Alexandra Hospital, Woollongabba, Australia
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Braet F, Wisse E. Structural and functional aspects of liver sinusoidal endothelial cell fenestrae: a review. COMPARATIVE HEPATOLOGY 2002; 1:1. [PMID: 12437787 PMCID: PMC131011 DOI: 10.1186/1476-5926-1-1] [Citation(s) in RCA: 518] [Impact Index Per Article: 22.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/06/2002] [Accepted: 08/23/2002] [Indexed: 12/13/2022]
Abstract
This review provides a detailed overview of the current state of knowledge about the ultrastructure and dynamics of liver sinusoidal endothelial fenestrae. Various aspects of liver sinusoidal endothelial fenestrae regarding their structure, origin, species specificity, dynamics and formation will be explored. In addition, the role of liver sinusoidal endothelial fenestrae in relation to lipoprotein metabolism, fibrosis and cancer will be approached.
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Affiliation(s)
- Filip Braet
- Laboratory for Cell Biology and Histology, Free University of Brussels (VUB), Laarbeeklaan 103, 1090 Brussels-Jette, Belgium
| | - Eddie Wisse
- Laboratory for Cell Biology and Histology, Free University of Brussels (VUB), Laarbeeklaan 103, 1090 Brussels-Jette, Belgium
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Moulin F, Copple BL, Ganey PE, Roth RA. Hepatic and extrahepatic factors critical for liver injury during lipopolysaccharide exposure. Am J Physiol Gastrointest Liver Physiol 2001; 281:G1423-31. [PMID: 11705747 DOI: 10.1152/ajpgi.2001.281.6.g1423] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
Bacterial endotoxin [lipopolysaccharide (LPS)] causes liver injury in vivo that is dependent on platelets, neutrophils [polymorphonuclear leukocytes (PMNs)], and several inflammatory mediators, including thrombin. We tested the hypothesis that thrombin contributes to LPS-induced hepatocellular injury through direct interactions with platelets and/or PMNs in vitro. Perfusion of isolated livers from LPS-treated rats with buffer containing thrombin resulted in a significant increase in alanine aminotransferase (ALT) activity in the perfusion medium, indicating hepatocellular damage. This effect was completely abolished by prior depletion of PMNs from the LPS-treated donor rats but not by depletion of platelets, suggesting interaction between thrombin and PMNs in the pathogenesis. Thrombin did not, however, enhance degranulation of rat PMNs in vitro, and it was not directly toxic to isolated rat hepatocytes in the presence of PMNs even after LPS exposure, suggesting that hepatocellular killing by the PMN-thrombin combination requires the intervention of an additional factor(s) within the liver. In livers from naive donors perfused with buffer containing PMNs and LPS, no injury occurred in the absence of thrombin. Addition of thrombin (10 nM) to the medium caused pronounced ALT release. These results indicate that thrombin and PMNs are sufficient extrahepatic requirements for LPS-induced hepatocellular damage in intact liver.
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Affiliation(s)
- F Moulin
- Department of Pharmacology and Toxicology, Michigan State University, East Lansing, Michigan 48824, USA
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Yoneyama K. Validation of confocal laser scanning microscopy for detecting intracellular calcium heterogeneity in liver slices. J Pharmacol Toxicol Methods 2001; 45:187-93. [PMID: 11755381 DOI: 10.1016/s1056-8719(01)00147-2] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
To investigate changes in the intracellular Ca(2+) ([Ca(2+)]i) in liver lobules under aerobic and hypoxic conditions, we measured [Ca(2+)]i in liver slices using a confocal laser scanning microscope (CLSM). The liver lobule is divided into 3 equal parts between the central vein and portal area, Zones 1, 2, and 3 from the portal side. [Ca(2+)]i in each zone of cultured rat liver lobules was measured by CLSM and a fluorescent Ca(2+) indicator (Rhod 2 AM). After the culture solution was changed to an Na(+)-free solution under aerobic conditions, the percentage of cells showing an increase in [Ca(2+)]i was 66.0+/-9.7% in Zone 1, 70.0+/-10.5% in Zone 2, and 94.0+/-9.7% in Zone 3. The percentage was significantly higher in Zone 3 than in Zones 1 and 2 (P< .01). Under hypoxic conditions, the percentage of cells showing an increase in [Ca(2+)]i was 6.0+/-9.7% in Zone 1, 8.0+/-10.3% in Zone 2, and 10.0+/-10.5% in Zone 3. There were no differences among the 3 zones. In all zones, the percentage was higher under aerobic conditions than under hypoxic conditions (P< .01). These results indicated that the increase in [Ca(2+)]i in liver lobules was heterogeneous. Measurement of [Ca(2+)]i in liver slices by CLSM was considered useful for studying heterogeneity between liver lobules, as well as between liver cells.
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Affiliation(s)
- K Yoneyama
- Showa University Health Service Center, Showa University, 1-4-5 Hatanodai, Shinagawa-ku Tokyo 142-8666, Japan.
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35
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Derbocio AM, Bracht AM, Constantin J, Caparroz-Assef SM, D'Avila RB, Ishii-Iwamoto EL. Zymosan-induced changes in glucose release and fatty acid oxidation in the perfused rat liver. J Biochem Mol Toxicol 2001; 14:252-61. [PMID: 10969997 DOI: 10.1002/1099-0461(2000)14:5<252::aid-jbt4>3.0.co;2-6] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
The aim of the present study was to investigate the actions of zymosan on glucose release and fatty acid oxidation in perfused rat livers and to determine if Kupffer cells and Ca2+ ions are implicated in these actions. Zymosan caused stimulation of glycogenolysis in livers from fed rats. In livers from fasted rats zymosan caused gradual inhibition of glucose production and oxygen consumption from lactate plus pyruvate. Ketogenesis, oxygen consumption, and [14C-]-CO2 production were inhibited by zymosan when the [1-14C]-palmitate was supplied exogenously. However, ketogenesis and oxygen consumption from endogenous sources were not inhibited. An interference with substrate-uptake by the liver may be the cause of the changes in gluconeogenesis and oxidation of fatty acids from exogenous sources. The pretreatment of the rats with gadolinium chloride and the removal of Ca2+ ions did not suppress the effects of zymosan on glucose release, a finding that argues against the participation of Kupffer cells or Ca2+ ions in the liver responses. The hepatic metabolic changes caused by zymosan could play a role in the systemic metabolic alterations reported to occur after in vivo zymosan administration.
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Affiliation(s)
- A M Derbocio
- Department of Biochemistry, University of Maringá, Brazil
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36
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Khan M, Contreras M, Singh I. Endotoxin-induced alterations of lipid and fatty acid compositions in rat liver peroxisomes. JOURNAL OF ENDOTOXIN RESEARCH 2001; 6:41-50. [PMID: 11061031 DOI: 10.1177/09680519000060010601] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
The structure/function of peroxisomal lipids in rat liver treated with a sublethal dose of endotoxin, a lipopolysaccharide (LPS), was investigated. Peroxisomes isolated from LPS-treated rat liver had remarkable alterations in lipid content compared with saline treated control liver peroxisomes. Cholesterol and phospholipids (PL) decreased significantly by 28.7% and 50.8%, respectively, leading to the change in the ratio of cholesterol/phospholipids (control 0.081 versus LPS 0.118, P < 0.001). A quantitative analysis from LPS-treated rat liver peroxisomes showed a general decrease in all classes of PL. No such alterations were observed in lipid content of other subcellular organelles. The peroxisomal fatty acid composition in LPS-treated animals was also altered. An analysis of fatty acid composition in PL and phosphatidylcholine from LPS-treated peroxisomes showed an increase in arachidonic acid (C20:4) and docosahexaenoic acid (C22:6). Very long chain (VLC) fatty acids (> C22:0) were also found increased in all classes of lipids in LPS-treated peroxisomes. Gadolinium chloride (GAD) mediated inactivation of Kupffer cells (KC) normalized cholesterol/PL ratio in LPS-treated peroxisomes. Collectively, the results indicate that the peroxisome metabolism of lipids and fatty acids is specifically altered in endotoxin-treated rat liver and at least part of the alterations may be mediated by factors released by KC.
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Affiliation(s)
- M Khan
- Department of Pediatrics, Medical University of South Carolina, Charleston 29425, USA
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Kubota Y, Takahashi S, Takahashi I, Patrick G. Different cytotoxic response to gadolinium between mouse and rat alveolar macrophages. Toxicol In Vitro 2000; 14:309-19. [PMID: 10906437 DOI: 10.1016/s0887-2333(00)00027-8] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The cytotoxicity of gadolinium (Gd) chloride was investigated in alveolar macrophages (AM) cultured in vitro. A marked difference in the cytotoxic response to Gd was found between mouse and rat AM. The viability of rat AM was decreased by exposure to Gd at doses more than 3 microM, while mouse AM appeared to be resistant even up to 1000 microM Gd exposure. The decrease in the viability of rat AM exposed to Gd at doses up to 1000 microM was mitigated by centrifugation and filtration of the culture medium containing Gd, or by the treatment of AM with lysosomotropic agents such as NH(4)Cl or chloroquine, suggesting that the cytotoxic response of rat AM to Gd at doses up to 1000 microM was dependent on the intracellular uptake and subsequent dissolution of Gd present in the culture medium in colloidal form. The phagocytic activity of mouse AM, evaluated by the uptake of latex particles, was higher than that of rat AM. Furthermore, quantitative analysis of Gd with inductively coupled plasma-mass spectrometry revealed that mouse AM took up a larger amount of Gd than rat AM. Therefore, the marked difference in the cytotoxic response to Gd between mouse and rat AM could not be attributed to the phagocytic activities for the colloidal form of Gd. The cytotoxic sensitivity of AM to Gd present in non-colloidal form was almost the same between mouse and rat AM. Therefore, it is suggested that the extent to which Gd-colloid phagocytosed is dissolved in the phago-lysosome or the subsequent process to exhibit the cytotoxicity may be different between mouse and rat AM.
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Affiliation(s)
- Y Kubota
- Environmental and Toxicological Sciences Research Group, National Institute of Radiological Sciences, Chiba, Japan.
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38
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Contreras MA, Khan M, Smith BT, Cimini AM, Gilg AG, Orak J, Singh I, Singh AK. Endotoxin induces structure-function alterations of rat liver peroxisomes: Kupffer cells released factors as possible modulators. Hepatology 2000; 31:446-55. [PMID: 10655269 DOI: 10.1002/hep.510310226] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/07/2022]
Abstract
We report that endotoxin treatment results in decreased amounts of peroxisomes as well as changes in structure and function of peroxisomal membranes. Peroxisomes isolated from the liver of control and treated animals showed a marked decrease in total protein, but no significant alteration in the sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) protein profile. However, the Western blot study of the peroxisomal beta-oxidation enzymes and catalase showed an increase in those enzymes in the peroxisomal peak of normal density in endotoxin-treated rats. Disintegration of peroxisomal membranes by carbonate treatment from endotoxin-treated liver and change in the fluidity of peroxisomal membranes suggests alterations in peroxisomal membrane structure. No such alterations were found in mitochondrial or microsomal membranes of endotoxin-treated livers. The lipid analysis of these organelles showed that the only organelle affected was the peroxisome, with a significant decrease in the phospholipid and cholesterol concentrations. To understand the mechanism of endotoxin-mediated alterations in peroxisomes, we studied the possible role of Kupffer cell secreted soluble factors (tumor necrosis factor alpha [TNF-alpha]) on the peroxisomal structure/function. Inactivation/elimination of Kupffer cells by gadolinium chloride before endotoxin treatment did not normalize the overall peroxisomal protein amount and the lipid composition of isolated peroxisomes. However, the levels of individual protein amount in remaining peroxisomes were normalized. Endotoxin also decreased peroxisomal beta-oxidation, and this was partially restored with gadolinium treatment. These results clearly show that peroxisomes are severely affected by endotoxin treatment and suggest that the damage to this organelle may contribute, at least in part, to endotoxin-induced hepatic cytotoxicity.
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Affiliation(s)
- M A Contreras
- Department of Pediatrics, Medical University of South Carolina, Charleston, SC, USA
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39
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Vajdová K, Smreková R, Kukan M, Jakubovský J, van Rooijen N, Horecký J, Lutterová M, Wsólová L. Endotoxin-induced aggravation of preservation-reperfusion injury of rat liver and its modulation. J Hepatol 2000; 32:112-20. [PMID: 10673075 DOI: 10.1016/s0168-8278(00)80197-x] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
BACKGROUND/AIMS In clinical transplantation, exposure of donors to gut-derived endotoxin occurs frequently and may adversely affect liver transplantation therapy. The aim of this study was to investigate: 1) whether brief exposure of rats to endotoxin before liver procurement aggravates the early phase of reperfusion injury of hepatic explants; and if so 2) whether Kupffer cell activation is a contributing factor to liver injury; and 3) whether heparin and pentoxifylline could minimize this effect. METHODS Male Wistar rats were injected with 0.2-4.0 mg/kg of Escherichia coli lipopolysaccharide 2 h prior to liver harvest. After preservation in University of Wisconsin cold-storage solution, the livers were reperfused using a blood-free perfusion model. To inactivate Kupffer cells, some rats were pretreated with gadolinium chloride or liposome-encapsulated dichloromethylene-diphosphonate before lipopolysaccharide administration. The other rats received lipopolysaccharide with heparin or pentoxifylline. RESULTS In a dose-independent fashion, lipopolysaccharide impaired portal flow during graft reperfusion. In a dose-dependent way, lipopolysaccharide increased lactate dehydrogenase release into the perfusate and decreased bile flow and bromosulfophthalein excretion. Gadolinium chloride, liposomal dichloromethylene-diphosphonate, heparin, and pentoxifylline reduced lactate dehydrogenase release by 34%, 43%, 59%, and 64%, respectively, and improved functional parameters of the liver. A 52-fold increased neutrophil infiltration in the liver sinusoids after lipopolysaccharide exposure was not affected significantly by the drugs studied; however, heparin reduced markedly neutrophil activation. CONCLUSIONS The results of this investigation provide direct evidence that aggravation of preservation-reperfusion injury of rat liver by endotoxin is mediated by Kupffer cell-dependent mechanism(s) and it can be minimized by heparin and pentoxifylline.
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Affiliation(s)
- K Vajdová
- Laboratory of Perfused Organs, Institute of Preventive and Clinical Medicine, Bratislava, Slovakia
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40
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Nagaoka MR, Kouyoumdjian M, Borges DR. The hepatic clearance of recombinant tissue-type plasminogen activator decreases after an inflammatory stimulus. Braz J Med Biol Res 2000; 33:119-25. [PMID: 10625883 DOI: 10.1590/s0100-879x2000000100016] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
We have shown that tissue-type plasminogen activator (tPA) and plasma kallikrein share a common pathway for liver clearance and that the hepatic clearance rate of plasma kallikrein increases during the acute-phase (AP) response. We now report the clearance of tPA from the circulation and by the isolated, exsanguinated and in situ perfused rat liver during the AP response (48-h ex-turpentine treatment). For the sake of comparison, the hepatic clearance of a tissue kallikrein and thrombin was also studied. We verified that, in vivo, the clearance of 125I-tPA from the circulation of turpentine-treated rats (2.2 +/- 0.2 ml/min, N = 7) decreases significantly (P = 0.016) when compared to normal rats (3.2 +/- 0.3 ml/min, N = 6). The AP response does not modify the tissue distribution of administered 125I-tPA and the liver accounts for most of the 125I-tPA (>80%) cleared from the circulation. The clearance rate of tPA by the isolated and perfused liver of turpentine-treated rats (15.5 +/- 1.3 microg/min, N = 4) was slower (P = 0.003) than the clearance rate by the liver of normal rats (22. 5 +/- 0.7 microg/min, N = 10). After the inflammatory stimulus and additional Kupffer cell ablation (GdCl3 treatment), tPA was cleared by the perfused liver at 16.2 +/- 2.4 microg/min (N = 5), suggesting that Kupffer cells have a minor influence on the hepatic tPA clearance during the AP response. In contrast, hepatic clearance rates of thrombin and pancreatic kallikrein were not altered during the AP response. These results contribute to explaining why the thrombolytic efficacy of tPA does not correlate with the dose administered.
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Affiliation(s)
- M R Nagaoka
- Laboratório de Hepatologia Experimental, Universidade Federal de São Paulo, São Paulo, SP, Brasil
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41
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Oneta CM, Mak KM, Lieber CS. Dilinoleoylphosphatidylcholine selectively modulates lipopolysaccharide-induced Kupffer cell activation. THE JOURNAL OF LABORATORY AND CLINICAL MEDICINE 1999; 134:466-70. [PMID: 10560939 DOI: 10.1016/s0022-2143(99)90167-1] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Polyenylphosphatidylcholine (PPC), a mixture of polyunsaturated phosphatidylcholines extracted from soybeans, protects against alcoholic and non-alcoholic liver injury. Because Kupffer cells mediate liver injury, we hypothesized that PPC may modulate their activation. The activation of Kupffer cells by lipopolysaccharide (LPS) leads to an enhanced production of cytokines. Among these, tumor necrosis factor-alpha(TNF-alpha) exerts mainly a hepatotoxic effect, whereas interleukin-1beta (IL-1beta) appears to be hepatoprotective. The present study evaluated whether dilinoleoylphosphatidylcholine (DLPC), the main component of PPC (40% to 52%), affects LPS-induced Kupffer cell activation in vitro. For comparison, palmitoyl-linoleoylphosphatidylcholine (PLPC), the other major component of PPC (23% to 24%), and distearoylphosphatidylcholine (DSPC), the saturated counterpart of DLPC, were also tested. Rat Kupffer cells were cultured in serum-free RPMI-1640 medium containing 10 micromol/L of either DLPC, PLPC, or DSPC in the presence or absence of LPS (1 microg/mL). After 20 hours in culture, the media were collected for cytokine measurements by enzyme-linked immunosorbent assays. LPS significantly stimulated TNF-alpha and IL-1beta production by 62% and 328%, respectively. Treatment of Kupffer cells with LPS plus DLPC decreased the production of TNF-alpha by 23% (12.17+/-1.83 pg/ng DNA vs 15.72 +/-2.74 pg/ng DNA, P < .05, n = 6) and increased that of IL-1beta by 17% (1.80 +/- 0.16 pg/ng DNA vs 1.54 +/- 0.08 pg/ng DNA, P< .05, n = 6). No effect of PLPC or DSPC on LPS-induced TNF-alpha or IL-1beta generation was observed, thereby illustrating the selective effect of DLPC in this process. Thus DLPC selectively modulates the LPS-induced activation of Kupffer cells by decreasing the production of the cytotoxic TNF-alpha while increasing that of the protective IL-1beta. This dual action of DLPC on cytokines may provide a mechanism for the protective effect against liver injury, but its significance still needs to be determined by in vivo studies.
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Affiliation(s)
- C M Oneta
- Alcohol Research and Treatment Center, Bronx Veterans Affairs Medical Center, NY 10468, USA
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42
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Abstract
The process of Ito cell activation, which is thought to be the central pathogenic mechanism in liver fibrogenesis, may involve distinct interactions with Kupffer cells (KCs) mediated by various cytokines and growth factors. The aim of this study was to determine whether targeting KC function using gadolinium chloride (GdCl(3)) interferes with the manifestation of carbon tetrachloride (CCl(4))-induced hepatic fibrosis, placing special emphasis on the process of microvascular remodelling. Using in vivo fluorescence microscopy, characteristic microvascular features of CCl(4)-induced liver fibrosis, progressively observed within the 8-week period of toxin exposure, were the significant reduction in sinusoidal density; the increase of venular vascular space; the perivenular accumulation of Ito cells, with concomitant collagen deposition; and the collapse of parenchymal tissue. GdCl(3) effectively attenuated sinusoidal rarefaction and delayed, but did not prevent, the process of Ito cell activation-associated collagen deposition. Strikingly, the 8-week modulation of KC function by GdCl(3) exhibited sustained hepatocellular fatty vacuolation with organ weight increase, liver enzyme release, and bile flow reduction. Thus, GdCl(3) treatment attenuates the hepatic microvascular response, but favours fatty change and only delays the development of liver fibrosis following CCl(4)-exposure.
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Affiliation(s)
- B Vollmar
- Institute for Clinical and Experimental Surgery, University of Saarland, Homburg/Saar, Germany.
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44
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Affiliation(s)
- C M Pastor
- Division of d'Hépatologie et de Gastroentérologie, Hôpital Cantonal Universitaire de Genève, Switzerland.
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Fernandes TR, Suzuki-Kemmelmeier F, Prado EC, Bracht A. The heterogeneous response of the bivascularly perfused rat liver to adenosine. Biochem Pharmacol 1999; 58:397-409. [PMID: 10424758 DOI: 10.1016/s0006-2952(99)00109-4] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
The heterogeneity of the liver parenchyma in relation to the metabolic response to adenosine was investigated using the bivascularly perfused rat liver in the anterograde and retrograde modes. Adenosine was infused into livers from fed rats according to four experimental protocols: (A) anterograde perfusion, adenosine via the portal vein; (B) anterograde perfusion, adenosine via the hepatic artery; (C) retrograde perfusion, adenosine via the hepatic vein; and (D) retrograde perfusion, adenosine via the hepatic artery. Due to the very pronounced concentration gradients generated by metabolic transformation, the infused adenosine attained maximal concentrations in different regions with each experimental protocol. The sinusoidal mean transit times (t(s)) were not changed by adenosine in anterograde perfusion, but were increased in retrograde perfusion. It was concluded that the vasoconstrictive elements are localized essentially in the presinusoidal region. Glucose release stimulation presented two kinetic components. The first one was rapid in both onset and decay with a peak around 30 sec; the second one developed more slowly (several minutes). The factors of the first kinetic component are possibly generated in the presinusoidal region or in the first periportal cells. The initial decrease in oxygen consumption seemed to be localized in the region just after the intrasinusoidal confluence of the ramifications of the portal vein and hepatic artery. Indomethacin decreased glucose release stimulation by adenosine in both anterograde and retrograde perfusion only when DMSO was the vehicle. The participation of eicosanoids in the generation of the effects of adenosine seems to be less important than hitherto believed.
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Affiliation(s)
- T R Fernandes
- Laboratory of Liver Metabolism, University of Maringa, Brazil
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Hamada E, Nishida T, Uchiyama Y, Nakamura J, Isahara K, Kazuo H, Huang TP, Momoi T, Ito T, Matsuda H. Activation of Kupffer cells and caspase-3 involved in rat hepatocyte apoptosis induced by endotoxin. J Hepatol 1999; 30:807-18. [PMID: 10365806 DOI: 10.1016/s0168-8278(99)80133-0] [Citation(s) in RCA: 59] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
BACKGROUND/AIMS Sepsis and lipopolysaccharides (LPS) cause mild to severe hepatic dysfunction. In this study, Kupffer cell activation, involvement of TNFalpha and caspases downstream of the TNFalpha receptor were examined in hepatocyte apoptosis induced by LPS. METHODS In in vivo experiments, male Sprague-Dawley rats were injected intravenously with LPS, and small amounts of the blood and liver were sampled to evaluate apoptosis. Kupffer cells were inactivated by pretreatment with gadolinium chloride for 2 days. In in vitro experiments, hepatocytes and Kupffer cells were separately isolated from rat livers using collagenase perfusion. RESULTS LPS induced time-dependent and dose-dependent increases in the number of TUNEL-positive cells, which coincided with the apoptotic features of hepatocytes demonstrated by electron microscopy and DNA ladder. Activation of caspase-3-like proteases was observed with an increase in the number of apoptotic hepatocytes. Immunostaining with activated caspase-3-specific antibody showed that caspase-3 was activated only in the cytoplasm of TUNEL-positive hepatocytes. Inactivation of Kupffer cells by gadolinium chloride was concomitantly accompanied by the prevention of caspase-3 activation, hepatocyte apoptosis and liver injury induced by LPS. The co-culture system of hepatocytes and Kupffer cells, but neither cell culture system, individually, showed LPS-induced hepatocyte apoptosis. Kupffer cell-conditioned medium induced hepatocyte apoptosis, whereas addition of anti-TNFalpha antibody to Kupffer cell-conditioned medium did not. Additions of acetyl-DEVD-CHO, acetyl-YVAD-CHO, and acetyl-IETD-CHO to Kupffer cell-conditioned medium decreased the number of apoptotic hepatocytes. CONCLUSIONS These results suggest that the activation of Kupffer cells, TNFalpha and caspases downstream of TNFR1 were involved in hepatocyte apoptosis induced by LPS.
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Affiliation(s)
- E Hamada
- First Department of Surgery, Osaka University Medical School, Suita, Japan
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Sarphie TG, Carey ME, Davidson JF, Soblosky JS. Scanning electron microscopy of the floor of the fourth ventricle in rats subjected to graded impact injury to the sensorimotor cortex. J Neurosurg 1999; 90:734-42. [PMID: 10193619 DOI: 10.3171/jns.1999.90.4.0734] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
OBJECT Respiratory dysfunction including apnea frequently follows head injury in humans. The purpose of this study was to identify any structural alterations in the region of brainstem respiratory nuclei that might account for immediate postinjury respiratory abnormalities in anesthetized experimental animals. METHODS Using scanning electron microscopy, the authors examined the floor of the fourth ventricle in injured rats after a piston strike to the sensorimotor cortex that depressed the dura 1, 2, or 4 mm. The rats were killed within minutes of injury. Cortical impact depths measuring either 1 or 2 mm (eight rats) produced no respiratory abnormalities, and the structural integrity of the ependymal lining of the ventricular floor in these animals was not compromised. Thirteen rats were subjected to impact to a 4-mm depth and 10 of these exhibited immediate temporary or permanent apnea. The medullae of nine of these rats were studied using scanning electron microscopy, and the fourth ventricular floors of all nine rats showed tears. Four rats that exhibited immediate, permanent apnea had tears in the caudal fourth ventricle floor near the obex, whereas five rats with no or only transient apnea had tears located more anteriorly, near the aqueduct or laterally. Changes in cerebrospinal fluid flow or pressure dynamics may have caused these tears. Light microscopy, focused near the area postrema, revealed a shearing defect through the ependyma of the fourth ventricular floor into the subjacent neuropil with a disruption of axonal pathways. CONCLUSIONS Respiratory neuronal network components lying within 2 mm of the area postrema may well have been disrupted by the caudal tears producing permanent apnea. A similar phenomenon could account for the transient or permanent postinjury apnea seen in humans with severe head injury.
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Affiliation(s)
- T G Sarphie
- Department of Cell Biology and Anatomy, Neurotrauma Research Laboratory, Louisiana State University Medical Center, New Orleans 70112, USA.
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Ahmad N, Gardner CR, Yurkow EJ, Laskin DL. Inhibition of macrophages with gadolinium chloride alters intercellular adhesion molecule-1 expression in the liver during acute endotoxemia in rats. Hepatology 1999; 29:728-36. [PMID: 10051474 DOI: 10.1002/hep.510290324] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
Cell adhesion molecules are important for localized accumulation of phagocytes at sites of tissue damage. In the present studies, we analyzed the effects of blocking hepatic macrophages on expression of beta2 integrins and intercellular adhesion molecule-1 (ICAM-1) adhesion molecules on liver cells during acute endotoxemia. Flow cytometric analysis revealed distinct subpopulations of macrophages from control animals that varied on the basis of their size and density. In contrast, hepatocytes and endothelial cells were relatively homogeneous. Treatment of rats with endotoxin (5 mg/kg, intravenously) resulted in a time-dependent increase in the percentage of small, dense macrophages and a progressive loss of larger, less-dense cells. In contrast, no major effects were observed on the physical properties of hepatocytes or endothelial cells. ICAM-1 was found to be constitutively expressed on endothelial cells and hepatocytes, as well as on macrophages. Induction of acute endotoxemia resulted in a time-dependent increase in ICAM-1 expression on hepatocytes, which was observed within 3 hours and reached a maximum after 24 hours. An increase in ICAM-1 expression was also observed on endothelial cells and on macrophages at 3 hours, followed by a decrease at 24 to 48 hours. Macrophages and endothelial cells also constitutively expressed beta2 integrins. Induction of acute endotoxemia had no effect on beta2 integrin expression by these cells. Pretreatment of rats with gadolinium chloride (GdCl3), a macrophage inhibitor known to block endotoxin-induced liver injury, abrogated the effects of endotoxin on ICAM-1 expression by hepatocytes and macrophages. In contrast, ICAM-1 expression on endothelial cells increased. Interestingly, treatment of rats with GdCl3 alone resulted in a marked increase in expression of ICAM-1 on endothelial cells and hepatocytes, and of beta2 integrins on macrophages and endothelial cells. Taken together, these data suggest that ICAM-1 is involved in mediating macrophage adherence and accumulation in the liver during endotoxemia. Furthermore, macrophages appear to regulate expression of this cell adhesion molecule on parenchymal cells.
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Affiliation(s)
- N Ahmad
- Department of Pharmacology and Toxicology, Rutgers University, Piscataway, NJ 08854-8020, USA
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Nakamura J, Nishida T, Hayashi K, Kawada N, Ueshima S, Sugiyama Y, Ito T, Sobue K, Matsuda H. Kupffer cell-mediated down regulation of rat hepatic CMOAT/MRP2 gene expression. Biochem Biophys Res Commun 1999; 255:143-9. [PMID: 10082670 DOI: 10.1006/bbrc.1999.0160] [Citation(s) in RCA: 53] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
Abstract
Lipopolysaccharides (LPS) induces intrahepatic cholestasis and canalicular multispecific organic anion transporter (CMOAT/MRP2) plays a central role in hepatic bilirubin transport. This study examined the role of Kupffer cell in LPS-induced cholestasis. Rats were injected intravenously with LPS. Kupffer cells were inactivated with gadolinium chloride (Gd). CMOAT/MRP2 mRNA expression was time- and dose-dependently decreased by LPS injection with a decrease in bile flow and an increase in serum bilirubin level. Gd pretreatment inhibited decrease in CMOAT/MRP2 mRNA and bile flow, and increase in serum bilirubin. Kupffer cell-conditioned medium decreased CMOAT/MRP2 expression. Addition of anti-IL-1 or anti-TNFalpha antibody restored CMOAT/MRP2 expression, whereas IL-1 and TNFalpha decreased the expression. MAP kinases were activated by addition of the conditioned medium, and addition of PD98059 or SB203580 restored CMOAT/MRP2 expression. These results suggest that LPS activates Kupffer cells to secrete IL-1 and TNFalpha, which in turn activate MAP kinases and decrease CMOAT/MRP2 expression.
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Affiliation(s)
- J Nakamura
- Biomedical Research Center, Osaka University Medical School, Osaka University Medical School, Yamadaoka 2-2, Suita, Osaka, 565-0871, Japan
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Deaciuc IV, D'Souza NB, Sarphie TG, Schmidt J, Hill DB, McClain CJ. Effects of exogenous superoxide anion and nitric oxide on the scavenging function and electron microscopic appearance of the sinusoidal endothelium in the isolated, perfused rat liver. J Hepatol 1999; 30:213-21. [PMID: 10068098 DOI: 10.1016/s0168-8278(99)80064-6] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/09/2023]
Abstract
BACKGROUND/AIMS Functional and morphological alterations of the hepatic sinusoidal endothelial cell occur in several models of experimental liver injury and in clinical settings. The causes of these alterations are multiple. The aim of this study was to test the hypothesis that the early functional impairment and morphological alterations of the sinusoidal endothelial cell and hepatic sinusoid associated with liver injury are mediated by free radical species, such as superoxide anion and nitric oxide. METHODS Isolated rat livers were perfused by recirculation with hemoglobin-free, Krebs-Henseleit bicarbonate buffer and presented with a source of superoxide anion (xanthine oxidase+hypoxanthine) or nitric oxide (S-nitroso-N-acetyl penicillamine). Hyaluronan uptake (an index of sinusoidal endothelial cell scavenging function), thiobarbituric acid-reactive substances content of the tissue (a marker of lipid peroxidation), reduced and oxidized glutathione (a marker of the thiol system oxidation/reduction state), lactate dehydrogenase and alanine aminotransferase activities (markers of cytolysis), as well as scanning and transmission electron microscopic appearance of the sinusoid were evaluated. RESULTS At the high concentrations used, both free radical generating systems suppressed hyaluronan uptake, increased malondialdehyde content of the tissue, enhanced the release of both liver enzymes, decreased the total glutathione content of the liver, and altered the ratio of reduced/oxidized glutathione. Both free radical species induced dose-dependent morphological alterations of the sinusoid, consisting of the appearance of large gaps replacing the sieve-plated fenestration. CONCLUSIONS The free radical species-induced functional impairment and morphological alterations of the liver sinusoid, presented in this study, closely resemble the early in vivo changes associated with liver injury under a variety of conditions, such as preservation and reperfusion, or administration of hepatotoxicants such as D-galactosamine, Gram-negative bacterial lipopolysaccharides, acetaminophen, alcohol and others. Therefore, we suggest that early liver sinusoid injury, observed under these conditions, can be attributed to the action of free radicals, such as superoxide anion and nitric oxide.
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Affiliation(s)
- I V Deaciuc
- Department of Internal Medicine, Albert B. Chandler Medical Center, University of Kentucky, Lexington, USA
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