1
|
Guixé-Muntet S, Quesada-Vázquez S, Gracia-Sancho J. Pathophysiology and therapeutic options for cirrhotic portal hypertension. Lancet Gastroenterol Hepatol 2024; 9:646-663. [PMID: 38642564 DOI: 10.1016/s2468-1253(23)00438-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/09/2023] [Revised: 11/28/2023] [Accepted: 11/28/2023] [Indexed: 04/22/2024]
Abstract
Portal hypertension represents the primary non-neoplastic complication of liver cirrhosis and has life-threatening consequences, such as oesophageal variceal bleeding, ascites, and hepatic encephalopathy. Portal hypertension occurs due to increased resistance of the cirrhotic liver vasculature to portal blood flow and is further aggravated by the hyperdynamic circulatory syndrome. Existing knowledge indicates that the profibrogenic phenotype acquired by sinusoidal cells is the initial factor leading to increased hepatic vascular tone and fibrosis, which cause increased vascular resistance and portal hypertension. Data also suggest that the phenotype of hepatic cells could be further impaired due to the altered mechanical properties of the cirrhotic liver itself, creating a deleterious cycle that worsens portal hypertension in the advanced stages of liver disease. In this Review, we discuss recent discoveries in the pathophysiology and treatment of cirrhotic portal hypertension, a condition with few pharmacological treatment options.
Collapse
Affiliation(s)
- Sergi Guixé-Muntet
- Liver Vascular Biology Research Group, IDIBAPS Biomedical Research Institute, CIBEREHD, Hospital Clínic de Barcelona, Barcelona, Spain
| | - Sergio Quesada-Vázquez
- Liver Vascular Biology Research Group, IDIBAPS Biomedical Research Institute, CIBEREHD, Hospital Clínic de Barcelona, Barcelona, Spain
| | - Jordi Gracia-Sancho
- Liver Vascular Biology Research Group, IDIBAPS Biomedical Research Institute, CIBEREHD, Hospital Clínic de Barcelona, Barcelona, Spain; Department of Visceral Surgery and Medicine, Inselspital, Bern University Hospital, University of Bern, Bern, Switzerland.
| |
Collapse
|
2
|
Gao J, Lan T, Kostallari E, Guo Y, Lai E, Guillot A, Ding B, Tacke F, Tang C, Shah VH. Angiocrine signaling in sinusoidal homeostasis and liver diseases. J Hepatol 2024:S0168-8278(24)00349-0. [PMID: 38763358 DOI: 10.1016/j.jhep.2024.05.014] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/29/2023] [Revised: 04/29/2024] [Accepted: 05/10/2024] [Indexed: 05/21/2024]
Abstract
The hepatic sinusoids are composed of liver sinusoidal endothelial cells (LSECs), which are surrounded by hepatic stellate cells (HSCs) and contain liver-resident macrophages called Kupffer cells, and other patrolling immune cells. All these cells communicate with each other and with hepatocytes to maintain sinusoidal homeostasis and a spectrum of hepatic functions under healthy conditions. Sinusoidal homeostasis is disrupted by metabolites, toxins, viruses, and other pathological factors, leading to liver injury, chronic liver diseases, and cirrhosis. Alterations in hepatic sinusoids are linked to fibrosis progression and portal hypertension. LSECs are crucial regulators of cellular crosstalk within their microenvironment via angiocrine signaling. This review discusses the mechanisms by which angiocrine signaling orchestrates sinusoidal homeostasis, as well as the development of liver diseases. Here, we summarise the crosstalk between LSECs, HSCs, hepatocytes, cholangiocytes, and immune cells in health and disease and comment on potential novel therapeutic methods for treating liver diseases.
Collapse
Affiliation(s)
- Jinhang Gao
- Laboratory of Gastroenterology and Hepatology, State Key Laboratory of Biotherapy, West China Hospital, Sichuan University, Chengdu, China; Department of Gastroenterology, West China Hospital, Sichuan University, Chengdu, China
| | - Tian Lan
- Laboratory of Gastroenterology and Hepatology, State Key Laboratory of Biotherapy, West China Hospital, Sichuan University, Chengdu, China; Department of Gastroenterology, West China Hospital, Sichuan University, Chengdu, China; Department of Hepatology and Gastroenterology, Charité Universitätsmedizin Berlin, Campus Virchow-Klinikum and Campus Charité Mitte, Berlin, Germany
| | - Enis Kostallari
- Division of Gastroenterology and Hepatology, Mayo Clinic, Rochester, MN, USA
| | - Yangkun Guo
- Laboratory of Gastroenterology and Hepatology, State Key Laboratory of Biotherapy, West China Hospital, Sichuan University, Chengdu, China; Department of Gastroenterology, West China Hospital, Sichuan University, Chengdu, China
| | - Enjiang Lai
- Laboratory of Gastroenterology and Hepatology, State Key Laboratory of Biotherapy, West China Hospital, Sichuan University, Chengdu, China; Department of Gastroenterology, West China Hospital, Sichuan University, Chengdu, China
| | - Adrien Guillot
- Department of Hepatology and Gastroenterology, Charité Universitätsmedizin Berlin, Campus Virchow-Klinikum and Campus Charité Mitte, Berlin, Germany
| | - Bisen Ding
- Key Laboratory of Birth Defects and Related Diseases of Women and Children of MOE, State Key Laboratory of Biotherapy, West China Second University Hospital, Sichuan University, Chengdu, China
| | - Frank Tacke
- Department of Hepatology and Gastroenterology, Charité Universitätsmedizin Berlin, Campus Virchow-Klinikum and Campus Charité Mitte, Berlin, Germany.
| | - Chengwei Tang
- Laboratory of Gastroenterology and Hepatology, State Key Laboratory of Biotherapy, West China Hospital, Sichuan University, Chengdu, China; Department of Gastroenterology, West China Hospital, Sichuan University, Chengdu, China.
| | - Vijay H Shah
- Division of Gastroenterology and Hepatology, Mayo Clinic, Rochester, MN, USA.
| |
Collapse
|
3
|
Sheng JY, Meng ZF, Li Q, Yang YS. Recent advances in promising drugs for primary prevention of gastroesophageal variceal bleeding with cirrhotic portal hypertension. Hepatobiliary Pancreat Dis Int 2024; 23:4-13. [PMID: 37580228 DOI: 10.1016/j.hbpd.2023.08.003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/14/2022] [Accepted: 08/01/2023] [Indexed: 08/16/2023]
Abstract
BACKGROUND Gastroesophageal variceal bleeding is one of the most severe complications of patients with cirrhosis. Although primary prevention drugs, including non-selective β-blockers, have effectively reduced the incidence of bleeding, their efficacy is limited due to side effects and related contraindications. With recent advances in precision medicine, precise drug treatment provides better treatment efficacy. DATA SOURCES Literature search was conducted in PubMed, MEDLINE and Web of Science for relevant articles published up to May 2022. Information on clinical trials was obtained from https://clinicaltrials.gov/ and http://www.chictr.org.cn/. RESULTS The in-depth understanding of the pathogenesis and advances of portal hypertension has enabled the discovery of multiple molecular targets for promising drugs. According to the site of action, these drugs could be classified into four classes: intrahepatic, extrahepatic, both intrahepatic and extrahepatic targets and others. All these classes of drugs offer advantages over traditional treatments in prevention of gastroesophageal variceal bleeding in patients with cirrhotic portal hypertension. CONCLUSIONS This review classified and summarized the promising drugs, which prevent gastroesophageal variceal bleeding by targeting specific markers of pathogenesis of portal hypertension, demonstrating the significance of using the precision medicine strategy to discover and develop promising drugs for the primary prevention of gastroesophageal variceal bleeding in patients with cirrhotic portal hypertension.
Collapse
Affiliation(s)
- Ji-Yao Sheng
- Department of Hepatobiliary and Pancreatic Surgery, the Second Hospital of Jilin University, Changchun 130041, China; Jilin Engineering Laboratory for Translational Medicine of Hepatobiliary and Pancreatic Diseases, the Second Hospital of Jilin University, Changchun 130041, China
| | - Zi-Fan Meng
- Department of Hepatobiliary and Pancreatic Surgery, the Second Hospital of Jilin University, Changchun 130041, China; Jilin Engineering Laboratory for Translational Medicine of Hepatobiliary and Pancreatic Diseases, the Second Hospital of Jilin University, Changchun 130041, China
| | - Qiao Li
- Department of Hepatobiliary and Pancreatic Surgery, the Second Hospital of Jilin University, Changchun 130041, China
| | - Yong-Sheng Yang
- Department of Hepatobiliary and Pancreatic Surgery, the Second Hospital of Jilin University, Changchun 130041, China; Jilin Engineering Laboratory for Translational Medicine of Hepatobiliary and Pancreatic Diseases, the Second Hospital of Jilin University, Changchun 130041, China.
| |
Collapse
|
4
|
The Hepatic Sinusoid in Chronic Liver Disease: The Optimal Milieu for Cancer. Cancers (Basel) 2021; 13:cancers13225719. [PMID: 34830874 PMCID: PMC8616349 DOI: 10.3390/cancers13225719] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2021] [Revised: 11/08/2021] [Accepted: 11/11/2021] [Indexed: 12/12/2022] Open
Abstract
Simple Summary During the development of chronic liver disease, the hepatic sinusoid undergoes major changes that further compromise the hepatic function, inducing persistent inflammation and the formation of scar tissue, together with alterations in liver hemodynamics. This diseased background may induce the formation and development of hepatocellular carcinoma (HCC), which is the most common form of primary liver cancer and a major cause of mortality. In this review, we describe the ways in which the dysregulation of hepatic sinusoidal cells—including liver sinusoidal cells, Kupffer cells, and hepatic stellate cells—may have an important role in the development of HCC. Our review summarizes all of the known sinusoidal processes in both health and disease, and possible treatments focusing on the dysregulation of the sinusoid; finally, we discuss how some of these alterations occurring during chronic injury are shared with the pathology of HCC and may contribute to its development. Abstract The liver sinusoids are a unique type of microvascular beds. The specialized phenotype of sinusoidal cells is essential for their communication, and for the function of all hepatic cell types, including hepatocytes. Liver sinusoidal endothelial cells (LSECs) conform the inner layer of the sinusoids, which is permeable due to the fenestrae across the cytoplasm; hepatic stellate cells (HSCs) surround LSECs, regulate the vascular tone, and synthetize the extracellular matrix, and Kupffer cells (KCs) are the liver-resident macrophages. Upon injury, the harmonic equilibrium in sinusoidal communication is disrupted, leading to phenotypic alterations that may affect the function of the whole liver if the damage persists. Understanding how the specialized sinusoidal cells work in coordination with each other in healthy livers and chronic liver disease is of the utmost importance for the discovery of new therapeutic targets and the design of novel pharmacological strategies. In this manuscript, we summarize the current knowledge on the role of sinusoidal cells and their communication both in health and chronic liver diseases, and their potential pharmacologic modulation. Finally, we discuss how alterations occurring during chronic injury may contribute to the development of hepatocellular carcinoma, which is usually developed in the background of chronic liver disease.
Collapse
|
5
|
Abstract
Liver sinusoidal endothelial cells (LSECs) form the wall of the hepatic sinusoids. Unlike other capillaries, they lack an organized basement membrane and have cytoplasm that is penetrated by open fenestrae, making the hepatic microvascular endothelium discontinuous. LSECs have essential roles in the maintenance of hepatic homeostasis, including regulation of the vascular tone, inflammation and thrombosis, and they are essential for control of the hepatic immune response. On a background of acute or chronic liver injury, LSECs modify their phenotype and negatively affect neighbouring cells and liver disease pathophysiology. This Review describes the main functions and phenotypic dysregulations of LSECs in liver diseases, specifically in the context of acute injury (ischaemia-reperfusion injury, drug-induced liver injury and bacterial and viral infection), chronic liver disease (metabolism-associated liver disease, alcoholic steatohepatitis and chronic hepatotoxic injury) and hepatocellular carcinoma, and provides a comprehensive update of the role of LSECs as therapeutic targets for liver disease. Finally, we discuss the open questions in the field of LSEC pathobiology and future avenues of research.
Collapse
|
6
|
Mendoza YP, Rodrigues SG, Bosch J, Berzigotti A. Effect of poorly absorbable antibiotics on hepatic venous pressure gradient in cirrhosis: A systematic review and meta-analysis. Dig Liver Dis 2020; 52:958-965. [PMID: 32736898 DOI: 10.1016/j.dld.2020.06.048] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/16/2020] [Revised: 06/24/2020] [Accepted: 06/29/2020] [Indexed: 12/11/2022]
Abstract
BACKGROUND The effects of poorly/non-absorbable antibiotics on hepatic venous pressure gradient (HVPG) are debated. AIM To analyze the effects of rifaximin or norfloxacin on HVPG and on markers of bacterial translocation and proinflammatory cytokines. METHODS We performed a systematic search of randomized clinical trials (RCTs) involving patients with cirrhosis and portal hypertension, assessing the effect of rifaximin or norfloxacin vs control on HVPG. Pooled analyses were based on random-effects models, heterogeneity was assessed by Cochran's Q, I2 statistic and subgroup analyses. RESULTS Five studies (215 patients) were included. Risk of bias was high in three. We found no significant differences using antibiotics versus control. The summary mean difference in HVPG was of -0.55 mmHg (95%CI:-1.52, 0.42; P = 0.27), with moderate heterogeneity (P = 0.15; I2 = 40%). RCTs with longer therapy (60-90 days) used non-selective-beta-blockers (NSBB) in both antibiotics and control arms. Subgroup analysis showed a significantly greater reduction in HVPG in the combination arm over controls (mean difference -1.46 mmHg [95%CI: -2.63, -0.28; P = 0.01]) with no heterogeneity (P = 0.46; I2 = 0%). Serum lipopolysaccharide-binding protein (LBP) significantly decreased with antibiotics, but with high heterogeneity (P < 0.001; I2 = 92%). CONCLUSIONS Rifaximin or norfloxacin did not significantly reduce HVPG in patients with cirrhosis and portal hypertension. Studies using antibiotic for longer periods on top of NSBB showed a significant decrease in HVPG.
Collapse
Affiliation(s)
- Yuly P Mendoza
- UVCM, Inselspital, Bern University Hospital, Department of Biomedical Research, University of Bern, Switzerland
| | - Susana G Rodrigues
- UVCM, Inselspital, Bern University Hospital, Department of Biomedical Research, University of Bern, Switzerland
| | - Jaime Bosch
- UVCM, Inselspital, Bern University Hospital, Department of Biomedical Research, University of Bern, Switzerland
| | - Annalisa Berzigotti
- UVCM, Inselspital, Bern University Hospital, Department of Biomedical Research, University of Bern, Switzerland.
| |
Collapse
|
7
|
Bosch J, Iwakiri Y. The portal hypertension syndrome: etiology, classification, relevance, and animal models. Hepatol Int 2017; 12:1-10. [PMID: 29064029 DOI: 10.1007/s12072-017-9827-9] [Citation(s) in RCA: 59] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/22/2017] [Accepted: 09/26/2017] [Indexed: 12/20/2022]
Abstract
BACKGROUND Portal hypertension is a key complication of portal hypertension, which is responsible for the development of varices, ascites, bleeding, and hepatic encephalopathy, which, in turn, cause a high mortality and requirement for liver transplantation. AIM This review deals with the present day state-of-the-art preventative treatments of portal hypertension in cirrhosis according to disease stage. Two main disease stages are considered, compensated and decompensated cirrhosis, the first having good prognosis and being mostly asymptomatic, and the second being heralded by the appearance of bleeding or non-bleeding complications of portal hypertension. RESULTS The aim of treatment in compensated cirrhosis is preventing clinical decompensation, the more frequent event being ascites, followed by variceal bleeding and hepatic encephalopathy. Complications are mainly driven by an increase of hepatic vein pressure gradient (HVPG) to values ≥10 mmHg (defining the presence of Clinically Significant Portal Hypertension, CSPH). Before CSPH, the treatment is limited to etiologic treatment of cirrhosis and healthy life style (abstain from alcohol, avoid/correct obesity…). When CSPH is present, association of a non-selective beta-blocker (NSBB), including carvedilol should be considered. NSBBs are mandatory if moderate/large varices are present. Patients should also enter a screening program for hepatocellular carcinoma. In decompensated patients, the goal is to prevent further bleeding if the only manifestation of decompensation was a bleeding episode, but to prevent liver transplantation and death in the common scenario where patients have manifested first non-bleeding complications. Treatment is based on the same principles (healthy life style..) associated with administration of NSBBs in combination if possible with endoscopic band ligation if there has been variceal bleeding, and complemented with simvastatin administration (20-40 mg per day in Child-Pugh A/B, 10-20 mg in Child C). Recurrence shall be treated with TIPS. TIPS might be indicated earlier in patients with: 1) Difficult/refractory ascites, who are not the best candidates for NSBBs, 2) patients having bleed under NSBBs or showing no HVPG response (decrease in HVPG of at least 20% of baseline or to values equal or below 12 mmHg). Decompensated patients shall all be considered as potential candidates for liver transplantation. CONCLUSION Treatment of portal hypertension has markedly improved in recent years. The present day therapy is based on accurate risk stratification according to disease stage.
Collapse
Affiliation(s)
- Jaime Bosch
- Hepatic Hemodynamic Laboratory, Liver Unit, Hospital Clínic-IDIBAPS, University of Barcelona, C.Villarroel 170, 08036, Barcelona, Spain. .,Centro de Investigación Biomédica en Red de Enfermedades Hepáticas y Digestivas (CIBEREHD), Instituto de Salud Carlos III, Barcelona, Spain. .,Swiss Liver Center, Hepatology, UVCM, Inselspital, University of Bern, Bern, Switzerland.
| | - Yasuko Iwakiri
- Section of Digestive Diseases, Department of Internal Medicine, Yale University School of Medicine, New Haven, CT, 06520, USA
| |
Collapse
|
8
|
Vilaseca M, García-Calderó H, Lafoz E, Ruart M, López-Sanjurjo CI, Murphy MP, Deulofeu R, Bosch J, Hernández-Gea V, Gracia-Sancho J, García-Pagán JC. Mitochondria-targeted antioxidant mitoquinone deactivates human and rat hepatic stellate cells and reduces portal hypertension in cirrhotic rats. Liver Int 2017; 37:1002-1012. [PMID: 28371136 DOI: 10.1111/liv.13436] [Citation(s) in RCA: 39] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/30/2017] [Accepted: 03/24/2017] [Indexed: 02/13/2023]
Abstract
BACKGROUND & AIMS In cirrhosis, activated hepatic stellate cells (HSC) play a major role in increasing intrahepatic vascular resistance and developing portal hypertension. We have shown that cirrhotic livers have increased reactive oxygen species (ROS), and that antioxidant therapy decreases portal pressure. Considering that mitochondria produce many of these ROS, our aim was to assess the effects of the oral mitochondria-targeted antioxidant mitoquinone on hepatic oxidative stress, HSC phenotype, liver fibrosis and portal hypertension. METHODS Ex vivo: Hepatic stellate cells phenotype was analysed in human precision-cut liver slices in response to mitoquinone or vehicle. In vitro: Mitochondrial oxidative stress was analysed in different cell type of livers from control and cirrhotic rats. HSC phenotype, proliferation and viability were assessed in LX2, and in primary human and rat HSC treated with mitoquinone or vehicle. In vivo: CCl4 - and thioacetamide-cirrhotic rats were treated with mitoquinone (5 mg/kg/day) or the vehicle compound, DecylTPP, for 2 weeks, followed by measurement of oxidative stress, systemic and hepatic haemodynamic, liver fibrosis, HSC phenotype and liver inflammation. RESULTS Mitoquinone deactivated human and rat HSC, decreased their proliferation but with no effects on viability. In CCl4 -cirrhotic rats, mitoquinone decreased hepatic oxidative stress, improved HSC phenotype, reduced intrahepatic vascular resistance and diminished liver fibrosis. These effects were associated with a significant reduction in portal pressure without changes in arterial pressure. These results were further confirmed in the thioacetamide-cirrhotic model. CONCLUSION We propose mitochondria-targeted antioxidants as a novel treatment approach against portal hypertension and cirrhosis.
Collapse
Affiliation(s)
- Marina Vilaseca
- Barcelona Hepatic Hemodynamic Laboratory, Liver Unit, Institut d'Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), Hospital Clínic de Barcelona, University of Barcelona Medical School, Barcelona, Spain
| | - Héctor García-Calderó
- Barcelona Hepatic Hemodynamic Laboratory, Liver Unit, Institut d'Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), Hospital Clínic de Barcelona, University of Barcelona Medical School, Barcelona, Spain.,Centro de Investigación Biomédica en Red de Enfermedades Hepáticas y Digestivas (CIBEREHD), Barcelona, Spain
| | - Erica Lafoz
- Barcelona Hepatic Hemodynamic Laboratory, Liver Unit, Institut d'Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), Hospital Clínic de Barcelona, University of Barcelona Medical School, Barcelona, Spain
| | - Maria Ruart
- Barcelona Hepatic Hemodynamic Laboratory, Liver Unit, Institut d'Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), Hospital Clínic de Barcelona, University of Barcelona Medical School, Barcelona, Spain
| | - Cristina Isabel López-Sanjurjo
- Barcelona Hepatic Hemodynamic Laboratory, Liver Unit, Institut d'Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), Hospital Clínic de Barcelona, University of Barcelona Medical School, Barcelona, Spain.,Centro de Investigación Biomédica en Red de Enfermedades Hepáticas y Digestivas (CIBEREHD), Barcelona, Spain
| | | | - Ramon Deulofeu
- Centro de Investigación Biomédica en Red de Enfermedades Hepáticas y Digestivas (CIBEREHD), Barcelona, Spain.,Department of Biochemistry and Chromatography, Hospital Clinic de Barcelona, Barcelona, Spain
| | - Jaume Bosch
- Barcelona Hepatic Hemodynamic Laboratory, Liver Unit, Institut d'Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), Hospital Clínic de Barcelona, University of Barcelona Medical School, Barcelona, Spain.,Centro de Investigación Biomédica en Red de Enfermedades Hepáticas y Digestivas (CIBEREHD), Barcelona, Spain
| | - Virginia Hernández-Gea
- Barcelona Hepatic Hemodynamic Laboratory, Liver Unit, Institut d'Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), Hospital Clínic de Barcelona, University of Barcelona Medical School, Barcelona, Spain.,Centro de Investigación Biomédica en Red de Enfermedades Hepáticas y Digestivas (CIBEREHD), Barcelona, Spain
| | - Jordi Gracia-Sancho
- Barcelona Hepatic Hemodynamic Laboratory, Liver Unit, Institut d'Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), Hospital Clínic de Barcelona, University of Barcelona Medical School, Barcelona, Spain.,Centro de Investigación Biomédica en Red de Enfermedades Hepáticas y Digestivas (CIBEREHD), Barcelona, Spain
| | - Juan Carlos García-Pagán
- Barcelona Hepatic Hemodynamic Laboratory, Liver Unit, Institut d'Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), Hospital Clínic de Barcelona, University of Barcelona Medical School, Barcelona, Spain.,Centro de Investigación Biomédica en Red de Enfermedades Hepáticas y Digestivas (CIBEREHD), Barcelona, Spain
| |
Collapse
|
9
|
Intrahepatic upregulation of MRTF-A signaling contributes to increased hepatic vascular resistance in cirrhotic rats with portal hypertension. Clin Res Hepatol Gastroenterol 2017; 41:303-310. [PMID: 28043789 DOI: 10.1016/j.clinre.2016.11.010] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/20/2016] [Revised: 11/09/2016] [Accepted: 11/22/2016] [Indexed: 02/04/2023]
Abstract
BACKGROUND Portal hypertension in cirrhosis is mediated, in part, by increased intrahepatic resistance, reflecting massive structural changes associated with fibrosis and intrahepatic vasoconstriction. Activation of the Rho/MRTF/SRF signaling pathway is essential for the cellular regulatory network of fibrogenesis. The aim of this study was to investigate MRTF-A-mediated regulation of intrahepatic fibrogenesis in cirrhotic rats. METHODS Portal hypertension was induced in rats via an injection of CCl4 oil. Hemodynamic measurements were obtained using a polyethylene PE-50 catheter and pressure transducers. Expression of hepatic fibrogenesis was measured using histological staining. Expression of protein was measured using western blotting. RESULTS Upregulation of MRTF-A protein expression in the livers of rats with CCl4-induced cirrhosis was relevant to intrahepatic resistance and hepatic fibrogenesis in portal hypertensive rats with increased modeling time. Inhibition of MRTF-A by CCG-1423 decelerated hepatic fibrosis, decreased intrahepatic resistance and portal pressure, and alleviated portal hypertension. CONCLUSION Increased intrahepatic resistance in rats with CCl4-induced portal hypertension is associated with an upregulation of MRTF-A signaling. Inhibition of this pathway in the liver can decrease hepatic fibrosis and intrahepatic resistance, as well as reduce portal pressure in cirrhotic rats with CCl4-induced portal hypertension.
Collapse
|
10
|
Vilaseca M, García-Calderó H, Lafoz E, García-Irigoyen O, Avila MA, Reverter JC, Bosch J, Hernández-Gea V, Gracia-Sancho J, García-Pagán JC. The anticoagulant rivaroxaban lowers portal hypertension in cirrhotic rats mainly by deactivating hepatic stellate cells. Hepatology 2017; 65:2031-2044. [PMID: 28142199 DOI: 10.1002/hep.29084] [Citation(s) in RCA: 57] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/05/2016] [Revised: 12/29/2016] [Accepted: 01/24/2017] [Indexed: 12/12/2022]
Abstract
UNLABELLED In cirrhosis, increased intrahepatic vascular resistance (IHVR) is the primary factor for portal hypertension (PH) development. Hepatic stellate cells (HSCs) play a major role increasing IHVR because, when activated, they are contractile and promote fibrogenesis. Protease-activated receptors (PARs) can activate HSCs through thrombin and factor Xa, which are known PAR agonists, and cause microthrombosis in liver microcirculation. This study investigates the effects of the oral anticoagulant, rivaroxaban (RVXB), a direct antifactor Xa, on HSC phenotype, liver fibrosis (LF), liver microthrombosis, and PH in cirrhotic rats. Hepatic and systemic hemodynamic, nitric oxide (NO) bioavailability, LF, HSC activation, and microthrombosis were evaluated in CCl4 and thioacetamide-cirrhotic rats treated with RVXB (20 mg/kg/day) or its vehicle for 2 weeks. RVXB significantly decreased portal pressure (PP) in both models of cirrhosis without changes in portal blood flow, suggesting a reduction in IHVR. RVXB reduced oxidative stress, improved NO bioavailability, and ameliorated endothelial dysfunction. Rivaroxaban deactivated HSC, with decreased alpha-smooth muscle actin and mRNA expression of other HSC activation markers. Despite this marked improvement in HSC phenotype, no significant changes in LF were identified. RVXB markedly reduced fibrin deposition, suggesting reduced intrahepatic microthrombosis. CONCLUSION RVXB decreases PP in two rat models of cirrhosis. This effect is mostly associated with decreased IHVR, enhanced NO bioavailability, HSC deactivation, and reduced intrahepatic microthrombosis. Our findings suggest that RVXB deserves further evaluation as a potential treatment for cirrhotic PH. (Hepatology 2017;65:2031-2044).
Collapse
Affiliation(s)
- Marina Vilaseca
- Barcelona Hepatic Hemodynamic Lab, Liver Unit, Hospital Clínic, Barcelona, Spain, Institut d'Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), Spain.,University of Barcelona Medical School, Barcelona, Spain
| | - Héctor García-Calderó
- Barcelona Hepatic Hemodynamic Lab, Liver Unit, Hospital Clínic, Barcelona, Spain, Institut d'Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), Spain.,Centro de Investigación Biomédica en Red de Enfermedades Hepáticas y Digestivas (CIBEREHD), Spain
| | - Erica Lafoz
- Barcelona Hepatic Hemodynamic Lab, Liver Unit, Hospital Clínic, Barcelona, Spain, Institut d'Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), Spain.,University of Barcelona Medical School, Barcelona, Spain
| | - Oihane García-Irigoyen
- Centro de Investigación Biomédica en Red de Enfermedades Hepáticas y Digestivas (CIBEREHD), Spain.,Centro de Investigación Médica Aplicada (CIMA), Division of Hepatology; University of Navarra, IDISNA (Instituto de Investigacion Sanitaria de Navarra), Pamplona, Spain
| | - Matías A Avila
- Centro de Investigación Biomédica en Red de Enfermedades Hepáticas y Digestivas (CIBEREHD), Spain.,Centro de Investigación Médica Aplicada (CIMA), Division of Hepatology; University of Navarra, IDISNA (Instituto de Investigacion Sanitaria de Navarra), Pamplona, Spain
| | | | - Jaume Bosch
- Barcelona Hepatic Hemodynamic Lab, Liver Unit, Hospital Clínic, Barcelona, Spain, Institut d'Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), Spain.,University of Barcelona Medical School, Barcelona, Spain.,Centro de Investigación Biomédica en Red de Enfermedades Hepáticas y Digestivas (CIBEREHD), Spain.,Swiss Liver Centre, Inselspital, Bern University, Switzerland
| | - Virginia Hernández-Gea
- Barcelona Hepatic Hemodynamic Lab, Liver Unit, Hospital Clínic, Barcelona, Spain, Institut d'Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), Spain.,Centro de Investigación Biomédica en Red de Enfermedades Hepáticas y Digestivas (CIBEREHD), Spain
| | - Jordi Gracia-Sancho
- Barcelona Hepatic Hemodynamic Lab, Liver Unit, Hospital Clínic, Barcelona, Spain, Institut d'Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), Spain.,University of Barcelona Medical School, Barcelona, Spain.,Centro de Investigación Biomédica en Red de Enfermedades Hepáticas y Digestivas (CIBEREHD), Spain
| | - Joan Carles García-Pagán
- Barcelona Hepatic Hemodynamic Lab, Liver Unit, Hospital Clínic, Barcelona, Spain, Institut d'Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), Spain.,University of Barcelona Medical School, Barcelona, Spain.,Centro de Investigación Biomédica en Red de Enfermedades Hepáticas y Digestivas (CIBEREHD), Spain
| |
Collapse
|
11
|
Simvastatin Attenuates Liver Injury in Rodents with Biliary Cirrhosis Submitted to Hemorrhage/Resuscitation. Shock 2017; 47:370-377. [DOI: 10.1097/shk.0000000000000734] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
|
12
|
Mai S, He Q, Wang H, Hu X, Luo Y, Yang Y, Kuang S, Tian X, Ma J, Yang J. 5-lipoxygenase activation is involved in the mechanisms of chronic hepatic injury in a rat model of chronic aluminum overload exposure. Toxicol Appl Pharmacol 2016; 305:259-266. [DOI: 10.1016/j.taap.2016.06.029] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2016] [Revised: 06/24/2016] [Accepted: 06/26/2016] [Indexed: 10/21/2022]
|
13
|
İçer M, Zengin Y, Gunduz E, Dursun R, Durgun HM, Turkcu G, Yuksel H, Üstündağ M, Guloglu C. Is montelukast as effective as N-acetylcysteine in hepatic injury due to acetaminophen intoxication in rats? ACTA ACUST UNITED AC 2016; 68:55-9. [DOI: 10.1016/j.etp.2015.09.008] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2015] [Revised: 08/13/2015] [Accepted: 09/18/2015] [Indexed: 12/19/2022]
|
14
|
Abstract
BACKGROUND Microbial infections are a relevant problem for patients with liver cirrhosis. Different types of bacteria are responsible for different kinds of infections: Escherichia coli and Klebsiella pneumoniae are frequently observed in spontaneous bacterial peritonitis or urinary tract infections, and Streptococcus pneumoniae and Mycoplasma pneumoniae in pulmonary infections. Mortality is up to 4-fold higher in infected patients with liver cirrhosis than in patients without infections. Key Messages: Infections in patients with liver cirrhosis are due to three major reasons: bacterial translocation, immune deficiency and an increased incidence of systemic infections. Nonparenchymal liver cells like Kupffer cells, sinusoidal endothelial cells and hepatic stellate cells are the first liver cells to come into contact with microbial products when systemic infection or bacterial translocation occurs. Kupffer cell (KC) activation by Toll-like receptor (TLR) agonists and endothelial sinusoidal dysfunction have been shown to be important mechanisms increasing portal pressure following intraperitoneal lipopolysaccharide pretreatment in cirrhotic rat livers. Reduced intrahepatic vasodilation and increased intrahepatic vasoconstriction are the relevant pathophysiological pathways. Thromboxane A2 and leukotriene (LT) C4/D4 have been identified as important vasoconstrictors. Accordingly, treatment with montelukast to inhibit the cysteinyl-LT1 receptor reduced portal pressure in cirrhotic rat livers. Clinical studies have demonstrated that activation of KCs, estimated by the amount of soluble CD163 in the blood, correlates with the risk for variceal bleeding. Additionally, intestinal decontamination with rifaximin in patients with alcohol-associated liver cirrhosis reduced the portal pressure and the risk for variceal bleeding. CONCLUSIONS TLR activation of nonparenchymal liver cells by pathogens results in portal hypertension. This might explain the pathophysiologic correlation between microbial infections and portal hypertension in patients with liver cirrhosis. These findings are the basis for both better risk stratifying and new treatment options, such as specific inhibition of TLR for patients with liver cirrhosis and portal hypertension.
Collapse
Affiliation(s)
- Christian J Steib
- Department of Medicine II, University Hospital LMU Munich, Liver Center Munich, Munich, Germany
| | | | | |
Collapse
|
15
|
Jana B, Czarzasta J, Jaroszewski J. Synthesis of leukotrienes in porcine uteri with endometritis induced by infection with Escherichia coli. Reprod Fertil Dev 2015; 26:1007-16. [PMID: 23924575 DOI: 10.1071/rd13191] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2013] [Accepted: 06/29/2013] [Indexed: 12/27/2022] Open
Abstract
Leukotrienes (LTs) are lipid mediators that play a significant role in the inflammatory process. Their production in inflamed uteri is not fully understood. The present experiment aimed to determine LTB4 and LTC4 amounts, 5-lipooxygenase (5-LO), LTA4 hydrolase (LTAH) and LTC4 synthase (LTCS) mRNA levels and protein expression in inflamed porcine uteri. On Day 3 of the oestrous cycle (Day 0 of the study), either Escherichia coli suspension or saline were infused into uterine horns. Collection of uterine tissues and washings took place eight or sixteen days later. In gilts suffering from endometritis increased LTB4 and LTC4 levels in the endometrium and washings and 5-LO mRNA levels in the myometrium on Days 8 and 16, 5-LO protein levels in the endometrium and myometrium on Day 8, LTAH mRNA and protein levels in the endometrium and myometrium on Days 8 and 16, respectively. Although LTCS mRNA and protein expression in the myometrium and LTCS protein expression in the endometrium were enhanced on Day 16 after Escherichia coli inoculation, LTCS mRNA levels decreased on Day 8 in both tissues. Our study shows the upregulation of LT production in inflamed porcine uteri, which suggests the importance of these factors to the process of uterine inflammation.
Collapse
Affiliation(s)
- Barbara Jana
- Division of Reproductive Biology, Institute of Animal Reproduction and Food Research of the Polish Academy of Sciences, Tuwima 10, 10-748 Olsztyn, Poland
| | - Joanna Czarzasta
- Division of Reproductive Biology, Institute of Animal Reproduction and Food Research of the Polish Academy of Sciences, Tuwima 10, 10-748 Olsztyn, Poland
| | - Jerzy Jaroszewski
- Department of Pharmacology and Toxicology, Faculty of Veterinary Medicine, University of Warmia and Mazury, Oczapowskiego 13, 10-719 Olsztyn, Poland
| |
Collapse
|
16
|
Bosch J, Groszmann RJ, Shah VH. Evolution in the understanding of the pathophysiological basis of portal hypertension: How changes in paradigm are leading to successful new treatments. J Hepatol 2015; 62:S121-30. [PMID: 25920081 PMCID: PMC4519833 DOI: 10.1016/j.jhep.2015.01.003] [Citation(s) in RCA: 144] [Impact Index Per Article: 16.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/17/2014] [Revised: 12/23/2014] [Accepted: 01/02/2015] [Indexed: 01/08/2023]
Abstract
Among the common complication of cirrhosis portal hypertension witnessed a major improvement of prognosis during the past decades. Principally due to the introduction of rational treatments based on new pathophysiological paradigms (concepts of thought) developed in the 1980s. The best example being the use of non-selective beta-blockers and of vasopressin analogs, somatostatin, and its analogs. Further refinement in the knowledge of the molecular mechanisms involved in the regulation of both the splanchnic and hepatic circulation has led to the emergence of new treatments, which are based on evidence that show not only structural but also vasoactive components increase the hepatic vascular resistance, as well as of angiogenesis. This knowledge and future improvements will most likely result in more effective treatment of portal hypertension and effective prevention of its complications in early stages.
Collapse
Affiliation(s)
- Jaume Bosch
- Hospital Clínic-IDIBAPS, University of Barcelona and Centro de Investigación, Biomédica en Red de Enfermedades Hepáticas y Digestivas (CIBERehd), Barcelona, Spain.
| | | | - Vijay H Shah
- Division of Gastroenterology and Hepatology, Mayo Clinic, Rochester, MN, USA
| |
Collapse
|
17
|
Di Pascoli M, Diví M, Rodríguez-Vilarrupla A, Rosado E, Gracia-Sancho J, Vilaseca M, Bosch J, García-Pagán JC. Resveratrol improves intrahepatic endothelial dysfunction and reduces hepatic fibrosis and portal pressure in cirrhotic rats. J Hepatol 2013; 58:904-10. [PMID: 23262250 DOI: 10.1016/j.jhep.2012.12.012] [Citation(s) in RCA: 103] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/28/2012] [Revised: 11/29/2012] [Accepted: 12/04/2012] [Indexed: 12/13/2022]
Abstract
BACKGROUND & AIMS Resveratrol, a polyphenol found in a variety of fruits, exerts a wide range of beneficial effects on the endothelium, regulates multiple vasoactive substances and decreases oxidative stress, factors involved in the pathophysiology of portal hypertension. Our study aimed at evaluating the effects of resveratrol on hepatic and systemic hemodynamics, hepatic endothelial dysfunction, and hepatic fibrosis in CCl₄ cirrhotic rats. METHODS Resveratrol (10 and 20 mg/kg/day) or its vehicle was administered to cirrhotic rats for two weeks and hepatic and systemic hemodynamics were measured. Moreover, we evaluated endothelial function by dose-relaxation curves to acetylcholine, hepatic NO bioavailability and TXA2 production. We also evaluated liver fibrosis by Sirius Red staining of liver sections, collagen-1, NFκB, TGFβ mRNA expression, and desmin and α-smooth muscle actin (α-SMA) protein expression, as a surrogate of hepatic stellate cell activation. RESULTS Resveratrol administration significantly decreased portal pressure compared to vehicle (12.1 ± 0.9 vs. 14.3 ± 2.2 mmHg; p <0.05) without significant changes in systemic hemodynamics. Reduction in portal pressure was associated with an improved vasodilatory response to acetylcholine, with decreased TXA2 production, increased endothelial NO, and with a significant reduction in liver fibrosis. The decrease in hepatic fibrosis was associated with a reduced collagen-1, TGFβ, NFκB mRNA expression and desmin and α-SMA protein expression. CONCLUSIONS Resveratrol administration reduces portal pressure, hepatic stellate cell activation and liver fibrosis, and improves hepatic endothelial dysfunction in cirrhotic rats, suggesting it may be a useful dietary supplement in the treatment of portal hypertension in patients with cirrhosis.
Collapse
Affiliation(s)
- Marco Di Pascoli
- Hepatic Hemodynamic Laboratory, Liver Unit, Hospital Clínic, Institut d'Investigacions Biomèdiques August Pi i Sunyer and Ciberehd, University of Barcelona, Spain
| | | | | | | | | | | | | | | |
Collapse
|
18
|
Guillaume M, Rodriguez-Vilarrupla A, Gracia-Sancho J, Rosado E, Mancini A, Bosch J, Garcia-Pagán JC. Recombinant human manganese superoxide dismutase reduces liver fibrosis and portal pressure in CCl4-cirrhotic rats. J Hepatol 2013; 58:240-6. [PMID: 22989570 DOI: 10.1016/j.jhep.2012.09.010] [Citation(s) in RCA: 57] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/26/2012] [Revised: 09/05/2012] [Accepted: 09/07/2012] [Indexed: 02/07/2023]
Abstract
BACKGROUND & AIMS High oxidative stress plays a major role in increasing hepatic vascular resistance in cirrhosis, by facilitating liver fibrosis and by increasing hepatic vascular tone. This study is aimed at investigating whether the use of the novel isoform of recombinant human manganese superoxide dismutase (rMnSOD) could be a new therapeutic strategy to reduce oxidative stress and portal hypertension in cirrhotic rats. METHODS In CCl(4)- and BDL-cirrhotic rats treated with rMnSOD (i.p. 15 μg/kg/day) or its vehicle for 7 days, mean arterial pressure (MAP), portal pressure (PP) and portal blood flow (PBF) or small mesenteric arterial flow (SMABF) were measured. In addition, in CCl(4)-cirrhotic rats, we evaluated the hepatic vasodilatory response to acetylcholine, liver fibrosis with Sirius red staining and hepatic stellate cell activation by α-smooth muscle actin (α-SMA) protein expression. RESULTS rMnSOD treatment significantly reduced PP either in CCl(4)- or BDL-cirrhotic rats without significant changes in splanchnic blood flow, suggesting a reduction in hepatic vascular resistance. MAP was not modified. Reduction in PP was associated with a significant reduction in liver fibrosis, and α-SMA protein expression as well as with improved vasodilatory response to acetylcholine. CONCLUSIONS Chronic rMnSOD administration to cirrhotic rats reduces portal pressure by reducing hepatic vascular resistance without deleterious effects on systemic hemodynamics, suggesting that it might constitute a new antioxidant to be considered as additional therapy for treating portal hypertension in cirrhosis.
Collapse
Affiliation(s)
- Maeva Guillaume
- Hepatic Haemodynamic Laboratory, Liver Unit, Hospital Clínic, Institut d'Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS) and CIBERehd, University of Barcelona, Spain
| | | | | | | | | | | | | |
Collapse
|
19
|
Kupffer cell depletion attenuates leptin-mediated methoxamine-stimulated portal perfusion pressure and thromboxane A2 release in a rodent model of NASH-cirrhosis. Clin Sci (Lond) 2012; 123:669-80. [PMID: 22734967 DOI: 10.1042/cs20110572] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
Cirrhotic portal hypertension is characterized by increased hepatic oxidative stress, AA (arachidonic acid)-derived TXA(2) (thromboxane A(2)) release and exaggerated hepatic response to the α-adrenergic agonist MTX (methoxamine). Besides promoting hepatic fibrosis, the role of hyperleptinaemia in the modulation of vascular response in NASH (non-alcoholic steatohepatitis) rat livers remains unknown. The aim of the present study was to explore the possible links between hyperleptinaemia and the disarrangement in the hepatic microcirculation. NASH-cirrhosis with hyperleptinaemia was induced in lean rats by feeding with an HF/MCD (high-fat/methionine-choline-deficient) diet. Portal haemodynamics, various substances, protein and mRNA expression and PUFA (polyunsaturated fatty acid) composition were measured. Finally, the effects of leptin pre-infusion on TXA(2) release and concentration-PPP (portal perfusion pressure) curves in response to MTX were evaluated by simultaneously pre-treatment with the Kupffer cell inactivators GdCl(3) (gadolinium chloride) or EC (encapsulated clodronate), the TXS (TXA(2) synthase) inhibitor furegrelate, the TP receptor (TXA(2) receptor) antagonist SQ29548 and the dual TXS/TP receptor antagonist BM567. In HF/MCD+leptin-lean rats, cirrhosis-induced PPP and MTX hyper-responsiveness were associated with increased hepatic TXA(2) production, TBARS (thiobarbituric acid-reacting substances) levels and the AA (arachidonic acid)/n-3 PUFA ratio, and up-regulation of hepatic leptin, FAS (fatty acid synthase), NADPH oxidase subunits, TXS, TP receptor, TGFβ(1) (transforming growth factor β(1)) proteins and mRNAs. Pre-infusion of leptin significantly enhanced MTX-stimulated PPP elevation and TXA(2) release, which were attenuated by GdCl(3) and EC pre-treatment. Concomitantly pre-incubation with BM567, but not furegrelate or SQ29548, significantly abolished the leptin-enhanced MTX-stimulated increase in PPP in NASH-cirrhotic rats. Hyperleptinaemia plays an important role in hyper-responsiveness to MTX in NASH-cirrhotic rat livers with portal hypertension. The leptin-enhanced MTX-stimulated increase in PPP is mediated by increased oxidative stress and Kupffer-cell-activated AA-derived TXA(2) release in NASH-cirrhotic rats.
Collapse
|
20
|
Pasarín M, La Mura V, Gracia-Sancho J, García-Calderó H, Rodríguez-Vilarrupla A, García-Pagán JC, Bosch J, Abraldes JG. Sinusoidal endothelial dysfunction precedes inflammation and fibrosis in a model of NAFLD. PLoS One 2012. [PMID: 22509248 DOI: 10.1371/journal,pone.0032785] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023] Open
Abstract
Non-alcoholic fatty liver disease (NAFLD) is the hepatic manifestation of the metabolic syndrome. Most morbidity associated with the metabolic syndrome is related to vascular complications, in which endothelial dysfunction is a major pathogenic factor. However, whether NAFLD is associated with endothelial dysfunction within the hepatic vasculature is unknown. The aims of this study were to explore, in a model of diet-induced overweight that expresses most features of the metabolic syndrome, whether early NAFLD is associated with liver endothelial dysfunction. Wistar Kyoto rats were fed a cafeteria diet (CafD; 65% of fat, mostly saturated) or a control diet (CD) for 1 month. CafD rats developed features of the metabolic syndrome (overweight, arterial hypertension, hypertryglyceridemia, hyperglucemia and insulin resistance) and liver steatosis without inflammation or fibrosis. CafD rats had a significantly higher in vivo hepatic vascular resistance than CD. In liver perfusion livers from CafD rats had an increased portal perfusion pressure and decreased endothelium-dependent vasodilation. This was associated with a decreased Akt-dependent eNOS phosphorylation and NOS activity. In summary, we demonstrate in a rat model of the metabolic syndrome that shows features of NAFLD, that liver endothelial dysfunction occurs before the development of fibrosis or inflammation.
Collapse
Affiliation(s)
- Marcos Pasarín
- Hepatic Hemodynamic Laboratory, Liver Unit, Hospital Clínic-IDIBAPS, CIBERrehd, University of Barcelona, Barcelona, Spain
| | | | | | | | | | | | | | | |
Collapse
|
21
|
Russo L, Gracia-Sancho J, García-Calderó H, Marrone G, García-Pagán JC, García-Cardeña G, Bosch J. Addition of simvastatin to cold storage solution prevents endothelial dysfunction in explanted rat livers. Hepatology 2012; 55:921-30. [PMID: 22031447 DOI: 10.1002/hep.24755] [Citation(s) in RCA: 86] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/16/2011] [Accepted: 09/29/2011] [Indexed: 12/11/2022]
Abstract
UNLABELLED Pathophysiological alterations in the endothelial phenotype result in endothelial dysfunction. Flow cessation, occurring during organ procurement for transplantation, triggers the endothelial dysfunction characteristic of ischemia/reperfusion injury, partly due to a reduction in the expression of the vasoprotective transcription factor Kruppel-like Factor 2 (KLF2). We aimed at (1) characterizing the effects of flow cessation and cold storage on hepatic endothelial phenotype, and (2) ascertaining if the consequences of cold stasis on the hepatic endothelium can be pharmacologically modulated, improving liver graft function. Expression of KLF2 and its vasoprotective programs was determined in (i) hepatic endothelial cells (HEC) incubated under cold storage conditions with or without the KLF2-inducer simvastatin, and (ii) rat livers not cold stored or preserved in cold University of Wisconsin solution (UWS) supplemented with simvastatin or its vehicle. In addition, upon warm reperfusion hepatic vascular resistance, endothelial function, nitric oxide vasodilator pathway, apoptosis, inflammation, and liver injury were evaluated in not cold stored livers or livers preserved in cold UWS supplemented with simvastatin or vehicle. Expression of KLF2 and its vasoprotective programs decrease in HEC incubated under cold storage conditions. Cold-stored rat livers exhibit a time-dependent decrease in KLF2 and its target genes, liver injury, increased hepatic vascular resistance, and endothelial dysfunction. The addition of simvastatin to the storage solution, maintained KLF2-dependent vasoprotective programs, prevented liver damage, inflammation, and oxidative stress and improved endothelial dysfunction. CONCLUSION Our results provide a rationale to evaluate the beneficial effects of a vasoprotective preservation solution on human liver procurement for transplantation.
Collapse
Affiliation(s)
- Lucia Russo
- Hepatic Hemodynamic Lab, Liver Unit, IMDIM, Hospital Clínic de Barcelona, IDIBAPS, Centro de Investigación Biomédica en Red en Enfermedades Hepáticas y Digestivas (CIBERehd), University of Barcelona, Barcelona, Spain
| | | | | | | | | | | | | |
Collapse
|
22
|
Pasarín M, La Mura V, Gracia-Sancho J, García-Calderó H, Rodríguez-Vilarrupla A, García-Pagán JC, Bosch J, Abraldes JG. Sinusoidal endothelial dysfunction precedes inflammation and fibrosis in a model of NAFLD. PLoS One 2012; 7:e32785. [PMID: 22509248 PMCID: PMC3317918 DOI: 10.1371/journal.pone.0032785] [Citation(s) in RCA: 164] [Impact Index Per Article: 13.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2011] [Accepted: 02/03/2012] [Indexed: 12/14/2022] Open
Abstract
Non-alcoholic fatty liver disease (NAFLD) is the hepatic manifestation of the metabolic syndrome. Most morbidity associated with the metabolic syndrome is related to vascular complications, in which endothelial dysfunction is a major pathogenic factor. However, whether NAFLD is associated with endothelial dysfunction within the hepatic vasculature is unknown. The aims of this study were to explore, in a model of diet-induced overweight that expresses most features of the metabolic syndrome, whether early NAFLD is associated with liver endothelial dysfunction. Wistar Kyoto rats were fed a cafeteria diet (CafD; 65% of fat, mostly saturated) or a control diet (CD) for 1 month. CafD rats developed features of the metabolic syndrome (overweight, arterial hypertension, hypertryglyceridemia, hyperglucemia and insulin resistance) and liver steatosis without inflammation or fibrosis. CafD rats had a significantly higher in vivo hepatic vascular resistance than CD. In liver perfusion livers from CafD rats had an increased portal perfusion pressure and decreased endothelium-dependent vasodilation. This was associated with a decreased Akt-dependent eNOS phosphorylation and NOS activity. In summary, we demonstrate in a rat model of the metabolic syndrome that shows features of NAFLD, that liver endothelial dysfunction occurs before the development of fibrosis or inflammation.
Collapse
Affiliation(s)
- Marcos Pasarín
- Hepatic Hemodynamic Laboratory, Liver Unit, Hospital Clínic-IDIBAPS, CIBERrehd, University of Barcelona, Barcelona, Spain
| | - Vincenzo La Mura
- Hepatic Hemodynamic Laboratory, Liver Unit, Hospital Clínic-IDIBAPS, CIBERrehd, University of Barcelona, Barcelona, Spain
| | - Jorge Gracia-Sancho
- Hepatic Hemodynamic Laboratory, Liver Unit, Hospital Clínic-IDIBAPS, CIBERrehd, University of Barcelona, Barcelona, Spain
| | - Héctor García-Calderó
- Hepatic Hemodynamic Laboratory, Liver Unit, Hospital Clínic-IDIBAPS, CIBERrehd, University of Barcelona, Barcelona, Spain
| | - Aina Rodríguez-Vilarrupla
- Hepatic Hemodynamic Laboratory, Liver Unit, Hospital Clínic-IDIBAPS, CIBERrehd, University of Barcelona, Barcelona, Spain
| | - Juan Carlos García-Pagán
- Hepatic Hemodynamic Laboratory, Liver Unit, Hospital Clínic-IDIBAPS, CIBERrehd, University of Barcelona, Barcelona, Spain
| | - Jaime Bosch
- Hepatic Hemodynamic Laboratory, Liver Unit, Hospital Clínic-IDIBAPS, CIBERrehd, University of Barcelona, Barcelona, Spain
| | - Juan G. Abraldes
- Hepatic Hemodynamic Laboratory, Liver Unit, Hospital Clínic-IDIBAPS, CIBERrehd, University of Barcelona, Barcelona, Spain
- * E-mail:
| |
Collapse
|
23
|
Abstract
Current guidelines recommend that all cirrhotic patients should undergo screening endoscopy at diagnosis to identify patients with varices at high risk of bleeding who will benefit from primary prophylaxis. This approach places a heavy burden upon endoscopy units and the repeated testing over time may have a detrimental effect on patient compliance. Noninvasive identification of patients at highest risk for oesophageal varices would limit investigation to those most likely to benefit. Upper GI endoscopy is deemed to be the gold standard against which all other tests are compared, but is not without its limitations. Multiple studies have been performed assessing clinical signs and variables relating to liver function, variables relating to liver fibrosis, and also to portal hypertension and hypersplenism. Whilst some tests are clearly preferable to patients, none appear to be as accurate as upper GI endoscopy in the diagnosis of oesophageal varices. The search for noninvasive tests continues.
Collapse
|
24
|
Insulin resistance and liver microcirculation in a rat model of early NAFLD. J Hepatol 2011; 55:1095-102. [PMID: 21356259 DOI: 10.1016/j.jhep.2011.01.053] [Citation(s) in RCA: 56] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/28/2010] [Revised: 01/14/2011] [Accepted: 01/27/2011] [Indexed: 12/23/2022]
Abstract
BACKGROUND & AIMS Insulin contributes to vascular homeostasis in peripheral circulation, but the effects of insulin in liver microvasculature have never been explored. The aim of this study was to assess the vascular effects of insulin in the healthy and fatty liver. METHODS Wistar rats were fed a control or a high fat diet (HFD) for 3days, while treated with a placebo, the insulin-sensitizer metformin, or the iNOS inhibitor 1400W. Vascular responses to insulin were evaluated in the isolated liver perfusion model. Insulin sensitivity at the sinusoidal endothelium was tested by endothelium-dependent vasodilation in response to acetylcholine in the presence or absence of insulin and by the level of liver P-eNOS after an insulin injection. RESULTS Rats from the HFD groups developed liver steatosis. Livers from the control group showed a dose-dependent hepatic vasodilation in response to insulin, which was blunted in livers from HFD groups. Metformin restored liver vascular insulin-sensitivity. Pre-treatment with insulin enhanced endothelium-dependent vasodilation of the hepatic vasculature and induced hepatic eNOS phosphorylation in control rats but not in HFD rats. Treatment with metformin or 1400W restored the capacity of insulin to enhance endothelium dependent vasodilation and insulin induced eNOS phosphorylation in HFD rats. CONCLUSIONS The administration of a HFD induces insulin resistance in the liver sinusoidal endothelium, which is mediated, at least in part, through iNOS upregulation and can be prevented by the administration of metformin. Insulin resistance at the hepatic vasculature can be detected earlier than inflammation or any other sign of advanced NALFD.
Collapse
|
25
|
García-Calderó H, Rodríguez-Vilarrupla A, Gracia-Sancho J, Diví M, Laviña B, Bosch J, García-Pagán JC. Tempol administration, a superoxide dismutase mimetic, reduces hepatic vascular resistance and portal pressure in cirrhotic rats. J Hepatol 2011; 54:660-5. [PMID: 21159403 DOI: 10.1016/j.jhep.2010.07.034] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/11/2010] [Revised: 07/22/2010] [Accepted: 07/22/2010] [Indexed: 02/08/2023]
Abstract
BACKGROUND & AIMS Increased superoxide in cirrhotic livers, by reducing nitric oxide bioavailability, contributes to increase intrahepatic vascular resistance to portal blood flow and as a consequence portal pressure. We aimed to evaluate whether a strategy directed to reduce superoxide using tempol, a small membrane permeable SOD-mimetic, is able to modulate intrahepatic nitric oxide content and reduce portal pressure in cirrhotic rats. METHODS Superoxide and nitric oxide were evaluated in control sinusoidal endothelial cells (SEC) pre-treated with the pro-oxidant diethyldithiocarbamate (DDC) and in CCl(4)-cirrhotic rat livers treated with tempol or vehicle. Mean arterial pressure, portal pressure, and portal blood flow were measured in control and cirrhotic rats treated with tempol (180μmol/kg/h; via ileocholic vein) or vehicle. In a subset of animals, hemodynamic measurements were performed after NO-inhibition with l-NAME. RESULTS Tempol reduced superoxide content and increased NO both in SEC and cirrhotic livers. In cirrhotic rats, but not in controls, tempol significantly reduced portal pressure, and increased portal blood flow, which most likely reflects a reduction in intrahepatic vascular resistance. Tempol significantly reduced mean arterial pressure. l-NAME prevented all these effects. CONCLUSIONS Tempol reduces superoxide, increases nitric oxide, and reduces portal pressure in sinusoidal endothelial cells and in cirrhotic livers. These results confirm that oxidative stress has a role in the pathogenesis of portal hypertension and supports the use of antioxidants in its treatment. However, when considering the use of antioxidants as additional therapy to treat portal hypertension, the potential to produce deleterious effects on systemic hemodynamics needs to be carefully evaluated.
Collapse
Affiliation(s)
- Héctor García-Calderó
- Centro de Investigación Biomédica en Red de Enfermedades Hepáticas y Digestivas, University of Barcelona, Spain
| | | | | | | | | | | | | |
Collapse
|
26
|
Portale Hypertension. PRAXIS DER VISZERALCHIRURGIE. GASTROENTEROLOGISCHE CHIRURGIE 2011. [PMCID: PMC7123479 DOI: 10.1007/978-3-642-14223-9_38] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
Während die Pathologie, die zur portalen Hypertension führt, im prähepatischen, hepatischen und posthepatischen venösen Gefäßbett liegen kann, machen die intrahepatischen Erkrankungen mit Abstand den Großteil aus. In unseren Breitengraden ist es die durch Alkoholabusus bedingte ethyltoxische Leberzirrhose, weltweit die durch Infektionen (HCV, HBV) bedingten Zirrhosen. Die chronische Hepatitis C mit ihren Komplikationen (Leberzellversagen, portale Hypertension und hepatozelluläres Karzinom) wird in den kommenden Jahren trotz moderner Therapieverfahren noch an Bedeutung gewinnen.
Collapse
|
27
|
Paiva LA, Maya-Monteiro CM, Bandeira-Melo C, Silva PMR, El-Cheikh MC, Teodoro AJ, Borojevic R, Perez SAC, Bozza PT. Interplay of cysteinyl leukotrienes and TGF-β in the activation of hepatic stellate cells from Schistosoma mansoni granulomas. Biochim Biophys Acta Mol Cell Biol Lipids 2010; 1801:1341-8. [PMID: 20817008 DOI: 10.1016/j.bbalip.2010.08.014] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2010] [Revised: 08/19/2010] [Accepted: 08/27/2010] [Indexed: 12/22/2022]
Abstract
Hepatic stellate cells (HSCs) have a critical role in liver physiology, and in the pathogenesis of liver inflammation and fibrosis. Here, we investigated the interplay between leukotrienes (LT) and TGF-β in the activation mechanisms of HSCs from schistosomal granulomas (GR-HSCs). First, we demonstrated that GR-HSCs express 5-lipoxygenase (5-LO), as detected by immunolocalization in whole cells and confirmed in cell lysates through western blotting and by mRNA expression through RT-PCR. Moreover, mRNA expression of 5-LO activating protein (FLAP) and LTC(4)-synthase was also documented, indicating that GR-HSCs have the molecular machinery required for LT synthesis. Morphological analysis of osmium and Oil-Red O-stained HSC revealed large numbers of small lipid droplets (also known as lipid bodies). We observed co-localization of lipid droplet protein marker (ADRP) and 5-LO by immunofluorescence microscopy. We demonstrated that GR-HSCs were able to spontaneously release cysteinyl-LTs (CysLTs), but not LTB(4,) into culture supernatants. CysLT production was highly enhanced after TGF-β-stimulation. Moreover, the 5-LO inhibitor zileuton and 5-LO gene deletion were able to inhibit the TGF-β-stimulated proliferation of GR-HSCs, suggesting a role for LTs in HSC activation. Here, we extend the immunoregulatory function of HSC by demonstrating that HSC from liver granulomas of schistosome-infected mouse are able to release Cys-LTs in a TGF-β-regulated manner, potentially impacting pathogenesis and liver fibrosis in schistosomiasis.
Collapse
Affiliation(s)
- Ligia A Paiva
- Laboratory of Immunopharmacology, Institute Oswaldo Cruz, Manguinhos, Rio de Janeiro, RJ, Brazil
| | | | | | | | | | | | | | | | | |
Collapse
|
28
|
Steib CJ, Hartmann AC, v Hesler C, Benesic A, Hennenberg M, Bilzer M, Gerbes AL. Intraperitoneal LPS amplifies portal hypertension in rat liver fibrosis. J Transl Med 2010; 90:1024-32. [PMID: 20212458 DOI: 10.1038/labinvest.2010.60] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Recent studies have shown that the risk of variceal bleeding in patients with liver cirrhosis increases with infections such as spontaneous bacterial peritonitis (SBP). In this study, we hypothesized that pretreatment with intraperitoneal LPS may escalate portal hypertension. In fibrotic livers (4 weeks after bile duct ligation, BDL), the activation of Kupffer cells (KCs) by zymosan (150 microg/ml) in the isolated non-recirculating liver perfusion system resulted in a transient increase in portal perfusion pressure. Pretreatment with intraperitoneal LPS (1 mg/kg body weight (b.w.) for 3 h) increased basal portal perfusion pressure, and prolonged the zymosan-induced increase from transient to a long-lasting increase that was sustained until the end of the experiments in BDL but not in sham-operated animals. Pretreatment with gadolinium chloride (10 mg/kg b.w.), MK-886 (0.6 mg/kg b.w.), Ly171883 (20 microM) or BM 13.177 (20 microM) reduced the maximal and long-lasting pressure increase in BDL animals by approximately 50-60%. The change in portal perfusion pressure was paralleled by a long-lasting production of cysteinyl leukotriene (Cys-LT) and thromboxane (TX) after LPS pretreatment. However, the response to vasoconstrictors was not altered by intraperitoneal LPS. Western blot analyses showed an increased Toll-like receptor (TLR)4 and MyD88 expression after LPS pretreatment. In vivo experiments confirmed that intraperitoneal LPS increased basal portal pressure, and extended the portal pressure increase produced by intraportal zymosan or by LPS infusion. In conclusion, upregulation of TLR4 and MyD88 expression in fibrotic livers confers hypersensitivity to LPS. This may lead to escalation of portal hypertension by production of TX and Cys-LT after endotoxin-induced KC activation. Therefore, LT inhibitors may represent a promising treatment option in addition to early administration of antibiotics in SBP.
Collapse
Affiliation(s)
- Christian J Steib
- Department of Medicine II (Gastroenterology and Hepatology), Liver Center Munich, University of Munich-Grosshadern, Munich, Germany.
| | | | | | | | | | | | | |
Collapse
|
29
|
Martell M, Coll M, Ezkurdia N, Raurell I, Genescà J. Physiopathology of splanchnic vasodilation in portal hypertension. World J Hepatol 2010; 2:208-20. [PMID: 21160999 PMCID: PMC2999290 DOI: 10.4254/wjh.v2.i6.208] [Citation(s) in RCA: 73] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/14/2010] [Revised: 06/09/2010] [Accepted: 06/16/2010] [Indexed: 02/06/2023] Open
Abstract
In liver cirrhosis, the circulatory hemodynamic alterations of portal hypertension significantly contribute to many of the clinical manifestations of the disease. In the physiopathology of this vascular alteration, mesenteric splanchnic vasodilation plays an essential role by initiating the hemodynamic process. Numerous studies performed in cirrhotic patients and animal models have shown that this splanchnic vasodilation is the result of an important increase in local and systemic vasodilators and the presence of a splanchnic vascular hyporesponsiveness to vasoconstrictors. Among the molecules and factors known to be potentially involved in this arterial vasodilation, nitric oxide seems to have a crucial role in the physiopathology of this vascular alteration. However, none of the wide variety of mediators can be described as solely responsible, since this phenomenon is multifactorial in origin. Moreover, angiogenesis and vascular remodeling processes also seem to play a role. Finally, the sympathetic nervous system is thought to be involved in the pathogenesis of the hyperdynamic circulation associated with portal hypertension, although the nature and extent of its role is not completely understood. In this review, we discuss the different mechanisms known to contribute to this complex phenomenon.
Collapse
Affiliation(s)
- María Martell
- María Martell, Mar Coll, Nahia Ezkurdia, Imma Raurell, Joan Genescà, Liver Diseases Laboratory, Liver Unit, Department of Internal Medicine, Hospital Universitari Vall d'Hebron, Institut de Recerca, Universitat Autònoma de Barcelona, Barcelona 08035, Spain
| | | | | | | | | |
Collapse
|
30
|
Steib CJ, Bilzer M, op den Winkel M, Pfeiler S, Hartmann AC, Hennenberg M, Göke B, Gerbes AL. Treatment with the leukotriene inhibitor montelukast for 10 days attenuates portal hypertension in rat liver cirrhosis. Hepatology 2010; 51:2086-96. [PMID: 20512996 DOI: 10.1002/hep.23596] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
UNLABELLED The mechanisms underlying intrahepatic vasoconstriction are not fully elucidated. Here we investigated the Kupffer cell (KC)-dependent increase in portal pressure by way of actions of vasoconstrictive cysteinyl leukotrienes (Cys-LTs). Liver cirrhosis was induced in rats by bile duct ligation (BDL for 4 weeks; controls: sham-operation) and thioacetamide application (18 weeks). Infusion of leukotriene (LT) C(4) or LTD(4) in isolated perfused livers (20 nM, BDL and sham) demonstrated that LTC(4) is a more relevant vasoconstrictor. In BDL animals the Cys-LT(1) receptor inhibitor montelukast (1 microM) reduced the maximal portal perfusion pressure following LTC(4) or LTD(4) infusion. The infusion of LTC(4) or D(4) in vivo (15 microg/kg b.w.) confirmed LTC(4) as the more relevant vasoconstrictor. Activation of KCs with zymosan (150 microg/mL) in isolated perfused BDL livers increased the portal perfusion pressure markedly, which was attenuated by LT receptor blockade (Ly171883, 20 microM). Cys-LTs in the effluent perfusate increased with KC activation but less with additional blockade of KCs with gadolinium chloride (10 mg/kg body weight, 48 and 24 hours pretreatment). KCs were isolated from normal rat livers and activated with zymosan or lipopolysaccharide at different timepoints. This resulted in an increase in Cys-LT production that was not influenced by preincubation with montelukast (1 microM). Infusion of LTC(4) (20 nM) and the thromboxane analog U46619 (0.1 microM) further enhanced portal pressure, indicating additive effects. Treatment with montelukast for 10 days resulted in an impressive reduction in the basal portal pressure and an attenuation of the KC-dependent increase in portal pressure. CONCLUSION Activation of isolated KCs produced Cys-LTs. Infusion of Cys-LTs increased portal pressure and, vice versa, treatment with montelukast reduced portal pressure in rat liver cirrhosis. Therefore, montelukast may be of therapeutic benefit for patients with portal hypertension.
Collapse
Affiliation(s)
- Christian J Steib
- Department of Medicine II (Gastroenterology and Hepatology), Liver Center Munich, University of Munich, Grosshadern, Munich, Germany.
| | | | | | | | | | | | | | | |
Collapse
|
31
|
Vollmar B, Menger MD. The hepatic microcirculation: mechanistic contributions and therapeutic targets in liver injury and repair. Physiol Rev 2009; 89:1269-339. [PMID: 19789382 DOI: 10.1152/physrev.00027.2008] [Citation(s) in RCA: 352] [Impact Index Per Article: 23.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023] Open
Abstract
The complex functions of the liver in biosynthesis, metabolism, clearance, and host defense are tightly dependent on an adequate microcirculation. To guarantee hepatic homeostasis, this requires not only a sufficient nutritive perfusion and oxygen supply, but also a balanced vasomotor control and an appropriate cell-cell communication. Deteriorations of the hepatic homeostasis, as observed in ischemia/reperfusion, cold preservation and transplantation, septic organ failure, and hepatic resection-induced hyperperfusion, are associated with a high morbidity and mortality. During the last two decades, experimental studies have demonstrated that microcirculatory disorders are determinants for organ failure in these disease states. Disorders include 1) a dysregulation of the vasomotor control with a deterioration of the endothelin-nitric oxide balance, an arterial and sinusoidal constriction, and a shutdown of the microcirculation as well as 2) an overwhelming inflammatory response with microvascular leukocyte accumulation, platelet adherence, and Kupffer cell activation. Within the sequelae of events, proinflammatory mediators, such as reactive oxygen species and tumor necrosis factor-alpha, are the key players, causing the microvascular dysfunction and perfusion failure. This review covers the morphological and functional characterization of the hepatic microcirculation, the mechanistic contributions in surgical disease states, and the therapeutic targets to attenuate tissue injury and organ dysfunction. It also indicates future directions to translate the knowledge achieved from experimental studies into clinical practice. By this, the use of the recently introduced techniques to monitor the hepatic microcirculation in humans, such as near-infrared spectroscopy or orthogonal polarized spectral imaging, may allow an early initiation of treatment, which should benefit the final outcome of these critically ill patients.
Collapse
Affiliation(s)
- Brigitte Vollmar
- Institute for Experimental Surgery, University of Rostock, Rostock, Germany.
| | | |
Collapse
|
32
|
Clària J, Horrillo R, Martínez-Clemente M, Morán-Salvador E, Titos E, González-Périz A, Ferré N. [Basic mechanisms of hepatocellular injury. Role of inflammatory lipid mediators]. GASTROENTEROLOGIA Y HEPATOLOGIA 2009; 31:682-92. [PMID: 19174085 DOI: 10.1016/s0210-5705(08)75816-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/13/2008] [Accepted: 03/14/2008] [Indexed: 10/20/2022]
Abstract
The presence of a lesion in the cellular parenchyma is common to a large number of chronic liver diseases, such as viral hepatitides, alcoholic hepatitis, chronic cholestasis and steatohepatitis. Although the pathogenesis may vary according to the etiological agent, a series of mechanisms is common to all. Notable among these mechanisms are Kupffer cell activation and inflammatory cell recruitment, free oxygen radical formation and the development of oxidative stress, cytokine production, mainly TNFa and TGFb, and inflammatory mediator release due to arachidonic acid oxidation through the COX-2 and 5-LO pathways.
Collapse
Affiliation(s)
- Juan Clària
- Servicio de Bioquímica y Genética Molecular, Hospital Clínic, Centro de Investigación Biomédica Esther Koplowitz (CIBEK) y CIBER de Enfermedades Hepáticas y Digestivas (CIBEREHD), IDIBAPS, Universitat de Barcelona, Barcelona, Spain.
| | | | | | | | | | | | | |
Collapse
|
33
|
Cuciureanu M, Căruntu ID, Păduraru O, Stoica B, Jerca L, Crauciuc E, Nechifor M. The protective effect of montelukast sodium on carbon tetrachloride induced hepatopathy in rat. Prostaglandins Other Lipid Mediat 2008; 88:82-8. [PMID: 19041730 DOI: 10.1016/j.prostaglandins.2008.10.004] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2008] [Revised: 10/21/2008] [Accepted: 10/30/2008] [Indexed: 01/09/2023]
Abstract
AIM This study investigates the effects of montelukast sodium (MK) (CysLTLT1 receptor antagonist) on CCl(4)induced hepatopathy on rat. MATERIAL AND METHODS We worked on 4 groups of 10 Wistar male rats each. The groups received as follows: group I (control group) - saline, group II - MK 5mg/kg/day i.p. for 5 days, group III - MK 5mg/kg/day i.p., 1 day prior to and 4 days concomitantly with CCl(4) p.o., 0.3ml/Kg/day and group IV - CCl(4), p.o., 0.3ml/Kg/day for 4 days. One day after the last administration, samples of blood were taken and alanine aminotransferase (ALT), total bilirubin (TB), direct bilirubin (DB), malondialdehyde (MDA), catalase (CAT) as well as total antioxidant capacity (TAC) were determined. The histopathological exam was performed. We also determined superoxide dismutase (SOD), MDA, CAT and GSH in liver homogenate. RESULTS Compared to group IV, group III exhibited statistically significant lower levels of ALT (318+/-15.75 versus 203.14+/-10.28 UI, p<0.0001), TB (3.16+/-0.30 versus 1.99+/-0.08mg/dl, p<0.0001), MDA in blood and in liver homogenate (4.98+/-1.71 versus 2.15+/-1.18nmol/ml, p=0.0004) and higher levels of SOD and CAT. Histopathologically, group IV presented important macro- and micro-vesicular hepatic steatosis and group III preserved lobular histoarchitecture and had less severe cellular lesions. CONCLUSION MK exhibits a partial hepatoprotective effect on rats treated with CCl(4).
Collapse
Affiliation(s)
- Magdalena Cuciureanu
- Department of Pharmacology, University of Medicine and Pharmacy, GRIGORE T. POPA, IASI, Romania.
| | | | | | | | | | | | | |
Collapse
|
34
|
Zhang ZQ, Qiu JF, Luo M, Sun YW, Zhao G, Chen W, Liu H, Wu ZY. Liposome-mediated gene transfer of endothelial nitric oxide synthase to cirrhotic rat liver decreases intrahepatic vascular resistance. J Gastroenterol Hepatol 2008; 23:e487-93. [PMID: 18070013 DOI: 10.1111/j.1440-1746.2007.05244.x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
BACKGROUND AND AIMS Nitric oxide (NO) production by endothelial nitric oxide synthase (eNOS) in sinusoidal endothelial cells is reduced in the injured liver and leads to intrahepatic portal hypertension. The present study evaluates the effects of liposome-mediated gene transfer of eNOS on the intrahepatic vascular resistance and portal venous pressure (PVP) in cirrhotic rats. METHODS Hepatic cirrhosis was induced in male Sprague-Dawley rats by intraperitoneal injection of carbon tetrachloride (CCl(4)), whereas the control normal rats were given the same dose of peanut oil. Plasmid eukaryotic expression vector (liposome-pcDNA3/eNOS) was injected into the portal vein of CCl(4) cirrhotic rats, whereas cirrhotic controls received the same dose of naked plasmid (liposome-pcDNA3) or Tris buffer, and control normal rats received the same dose of Tris buffer. Five days after gene transfer, the levels of eNOS mRNA and protein, NO production, PVP and the changes of hepatic intrahepatic vascular resistance were investigated. RESULTS Five days after eNOS gene transfer, the levels of eNOS mRNA, eNOS protein and NO production in cirrhotic rats increased remarkably, while hepatic vascular resistance and PVP decreased significantly in cirrhotic rats. CONCLUSION Liposome-mediated eNOS gene transfer via intraportal injection is feasible and the increase of intrahepatic eNOS leads to a marked decrease in introhepatic vascular resistance and PVP. These data indicate that intrahepatic eNOS plays an important role in the pathogenesis of portal hypertension and gene transfer of eNOS is a potential and novel therapy for portal hypertension.
Collapse
Affiliation(s)
- Zhi-Qi Zhang
- Department of General Surgery, Renji Hospital, School of Medicine, Shanghai Jiaotong University, Shanghai, China.
| | | | | | | | | | | | | | | |
Collapse
|
35
|
Matei V, Rodríguez-Vilarrupla A, Deulofeu R, García-Calderó H, Fernández M, Bosch J, Garcia-Pagán JC. Three-day tetrahydrobiopterin therapy increases in vivo hepatic NOS activity and reduces portal pressure in CCl4 cirrhotic rats. J Hepatol 2008; 49:192-7. [PMID: 18534709 DOI: 10.1016/j.jhep.2008.04.014] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/23/2007] [Revised: 04/04/2008] [Accepted: 04/04/2008] [Indexed: 02/08/2023]
Abstract
BACKGROUND/AIMS Tetrahydrobiopterin is an essential cofactor for NOS enzymes to synthesize NO. It has been suggested that reduced intrahepatic tetrahydrobiopterin decreases intrahepatic NO and contributes to increase hepatic vascular resistance and portal pressure in cirrhosis. The main aim of the study was to evaluate the effect of tetrahydrobiopterin supplementation in portal pressure in CCl4 cirrhotic rats. METHODS Cirrhotic rats received vehicle or tetrahydrobiopterin (10mg/kg/day i.p.) for 3 days. Hepatic and systemic hemodynamics and hepatic tetrahydrobiopterin, NOS activity and cGMP levels were measured. In addition, hepatic and systemic hemodynamics were evaluated in normal rats in which tetrahydrobiopterin deficiency was induced by administrating 2,4-diamino-6-hydroxy-pyrimidine (DAHP) for 8h. RESULTS In cirrhotic rats, tetrahydrobiopterin administration increased liver NOS activity and cGMP levels and markedly and significantly reduced portal pressure. Amelioration of portal hypertension was associated with a normalization of arterial pressure. In normal rats DAHP decreased hepatic tetrahydrobiopterin and NOS activity and increased hepatic vascular tone. These effects of DAHP administration were corrected by tetrahydrobiopterin supplementation. CONCLUSIONS The present study shows that tetrahydrobiopterin markedly reduces portal hypertension and improves systemic hemodynamics in cirrhotic rats. These data support the concept that tetrahydrobiopterin supplementation may represent a new therapeutic strategy for portal hypertension.
Collapse
Affiliation(s)
- Vasilica Matei
- Hepatic Hemodynamic Laboratory, Liver Unit, Institut de Malalties Digestives i Metabòliques, Hospital Clínic, Institut d'Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), Villarroel 170, 08036 Barcelona, Spain
| | | | | | | | | | | | | |
Collapse
|
36
|
Abstract
Increased intrahepatic resistance is the initial event to the increased portal pressure and development portal hypertension in cirrhosis. Narrowing of the sinusoids due to anatomic changes is the main component of the increased intrahepatic resistance. However, a dynamic component is also involved in the increased vascular tone in cirrhosis. The imbalance between the hyperresponsiveness and overproduction of vasoconstrictors (mainly endothelin-1 and cyclooxygenase-derived prostaglandins) and the hyporesponsiveness and impaired production of vasodilators [mainly nitric oxide (NO)] are the mechanisms responsible of the increased vascular tone in the sinusoidal/postsinusoidal area. In contrast, the vascular resistance in the hepatic artery, which is determined in the presinusoidal area, is decreased due to increased vasodilators (NO and adenosine). This suggests different availabilities of NO in the intrahepatic circulation with preserved production in the presinusoidal area and impaired production in the sinusoidal/postsinusoidal area.
Collapse
|
37
|
Abstract
Cirrhosis is characterized by marked abnormalities in the hepatic circulation. Functionally, there is an increased vascular tone and impaired flow-mediated vasorelaxation, whereas anatomically there is sinusoidal remodeling and capillarization, angiogenesis, venous thrombosis, and vascular distortion, all contributing to increase hepatic vascular resistance and portal hypertension. However, vascular changes are not limited to the liver, but are also present in the splanchnic organs, heart, lungs, kidney, brain, and skin. Advances in the knowledge of the mechanisms of these abnormalities have disclosed new targets for therapy and ultimately improved survival.
Collapse
|
38
|
Gracia-Sancho J, Laviña B, Rodríguez-Vilarrupla A, Brandes RP, Fernández M, Bosch J, García-Pagán JC. Evidence against a role for NADPH oxidase modulating hepatic vascular tone in cirrhosis. Gastroenterology 2007; 133:959-66. [PMID: 17854599 DOI: 10.1053/j.gastro.2007.06.021] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/10/2007] [Accepted: 05/17/2007] [Indexed: 12/20/2022]
Abstract
BACKGROUND & AIMS Increased hepatic vascular resistance in cirrhosis is in part due to reduced nitric oxide (NO) bioavailability. This is related to insufficient NO synthesis from endothelial nitric oxide synthase and to enhanced NO scavenging by superoxide radicals (O(2)(-)). Nicotinamide adenine dinucleotide phosphate (NADPH)-oxidase is an important source of O(2)(-) that increases vascular tone in different cardiovascular disorders. Thus, our aims were to study the molecular and biochemical state of NADPH-oxidase in cirrhotic livers and to investigate its possible role in modulating hepatic vascular tone in cirrhosis. METHODS NADPH-oxidase expression and enzymatic activity were determined in control (n = 8) and CCl(4)-cirrhotic (n = 8) rat livers. Additional control (n = 6) and CCl(4)-cirrhotic (n = 10) rats were treated with apocynin (a selective NADPH-oxidase inhibitor) or its vehicle. Mean arterial pressure, portal pressure, and superior mesenteric arterial blood flow were measured in vivo. Moreover, hepatic endothelial function was evaluated in isolated and perfused rat livers by dose-response curves to acetylcholine. In addition, in 6 control and 6 cirrhotic human livers NADPH-oxidase activity and expression were evaluated. RESULTS Rat cirrhotic livers had no increased NADPH-oxidase protein expression or activity in relation to control livers. NADPH-oxidase inhibition did not modify splanchnic or systemic hemodynamics in control or cirrhotic rats and did not improve the impaired endothelial-dependent vasodilatory response to acetylcholine of cirrhotic livers. Human cirrhotic livers also did not exhibit increased NADPH-oxidase expression or activity. CONCLUSIONS Our study shows that NADPH-oxidase activity is decreased in the cirrhotic livers and therefore cannot explain increased hepatic O(2)(-), endothelial dysfunction, and increased vascular tone in cirrhotic livers.
Collapse
Affiliation(s)
- Jorge Gracia-Sancho
- Hepatic Hemodynamic Laboratory, Liver Unit, IMDIM, Hospital Clínic, Ciberehd and Institut d'Investigacions Biomèdiques August Pi i Sunyer, University of Barcelona, Spain
| | | | | | | | | | | | | |
Collapse
|
39
|
Gracia-Sancho J, Laviña B, Rodríguez-Vilarrupla A, García-Calderó H, Bosch J, García-Pagán JC. Enhanced vasoconstrictor prostanoid production by sinusoidal endothelial cells increases portal perfusion pressure in cirrhotic rat livers. J Hepatol 2007; 47:220-7. [PMID: 17459512 DOI: 10.1016/j.jhep.2007.03.014] [Citation(s) in RCA: 87] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/28/2006] [Revised: 02/14/2007] [Accepted: 03/03/2007] [Indexed: 12/12/2022]
Abstract
BACKGROUND/AIMS Cyclooxygenase-1 (COX-1) is overexpressed in sinusoidal endothelial cells (SEC) of cirrhotic rat livers, and through an enhanced production of vasoconstrictor prostanoids contributes to increase intrahepatic resistance. Our study was aimed at investigating the role of enhanced AA bioavailability modulating the hepatic vascular tone of cirrhotic livers and identifying which prostanoid is involved. METHODS SEC isolated from control and cirrhotic rat livers were incubated with AA, methoxamine or vehicle. TXA(2) was quantified. In addition, portal perfusion pressure (PP) response curves to AA were performed in rat livers pre-incubated with vehicle, SC-560 (COX-1 inhibitor), Furegrelate (inhibitor of TXA(2) synthesis) and SQ-29548 (PGH(2)/TXA(2) receptor blocker). cPLA2 activity was determined in control and cirrhotic livers. RESULTS AA and methoxamine incubation promoted a significant increase in TXA(2) release by Cirrhotic-SEC, but not in Control-SEC. AA produced a dose-dependent increase in the PP, associated with increased TXA(2) release. These responses were significantly greater in cirrhotic livers. COX-1 inhibition and PGH(2)/TXA(2) receptor blockade, but not TXA(2) synthase inhibition, markedly attenuated the PP response to AA of cirrhotic livers. Additionally, cirrhotic livers exhibited significantly increased cPLA2 activity. CONCLUSIONS An enhanced production of vasoconstrictor prostanoids, probably PGH(2), by SEC contributes to increase vascular tone of cirrhotic livers.
Collapse
Affiliation(s)
- Jorge Gracia-Sancho
- Hepatic Hemodynamic Laboratory, Liver Unit, IMDIM, Hospital Clínic, Ciberehd and Institut d'Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), University of Barcelona, Villarroel 170, 08036 Barcelona, Spain
| | | | | | | | | | | |
Collapse
|
40
|
Abraldes JG, Rodríguez-Vilarrupla A, Graupera M, Zafra C, García-Calderó H, García-Pagán JC, Bosch J. Simvastatin treatment improves liver sinusoidal endothelial dysfunction in CCl4 cirrhotic rats. J Hepatol 2007; 46:1040-6. [PMID: 17335931 DOI: 10.1016/j.jhep.2007.01.020] [Citation(s) in RCA: 168] [Impact Index Per Article: 9.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/06/2006] [Revised: 01/29/2007] [Accepted: 01/29/2007] [Indexed: 12/12/2022]
Abstract
BACKGROUND/AIMS Sinusoidal endothelial dysfunction with decreased nitric oxide (NO) production contributes to increased hepatic resistance in cirrhosis. Statins improve endothelial dysfunction in peripheral vasculature. This study was designed to characterize the hemodynamic and molecular effects of statins in cirrhotic rats. METHODS Systemic and splanchnic hemodynamics were evaluated in CCl(4) ascitic cirrhotic rats treated with placebo or simvastatin (25 mg/kg/day, for 3 days), at baseline and after volume expansion. Vascular responses of liver vasculature were evaluated after isolation and perfusion of the liver. RESULTS There were no differences in baseline hemodynamics in rats treated with simvastatin or placebo. However, in rats treated with simvastatin the increase in portal pressure induced by volume expansion was significantly attenuated. In isolated and perfused cirrhotic livers simvastatin pre-treatment significantly attenuated the pressure response to methoxamine, and significantly improved paradoxical vasoconstriction induced by acetylcholine. These effects were not observed in the presence of a nitric oxide synthase inhibitor. Simvastatin increased eNOS expression, Akt-dependent eNOS phosphorylation and cGMP liver content. CONCLUSIONS The administration of simvastatin might constitute a new way to selectively increase NO availability in the cirrhotic liver circulation and, therefore improve the vascular disturbances that contribute to portal hypertension.
Collapse
Affiliation(s)
- Juan G Abraldes
- Hepatic Hemodynamic Laboratory, Liver Unit, IMDIM, Hospital Clínic, Ciberehd, University of Barcelona, Villarroel 170, 08036 Barcelona, Spain
| | | | | | | | | | | | | |
Collapse
|
41
|
Yang YY, Lin HC, Huang YT, Lee TY, Hou MC, Wang YW, Lee FY, Lee SD. Effect of chronic CB1 cannabinoid receptor antagonism on livers of rats with biliary cirrhosis. Clin Sci (Lond) 2007; 112:533-42. [PMID: 17176248 DOI: 10.1042/cs20060260] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
Recent studies have shown that the activated endocannabinoid system participates in the increase in IHR (intrahepatic resistance) in cirrhosis. The increased hepatic production of vasoconstrictive eicosanoids is involved in the effect of endocannabinoids on the hepatic microcirculation in cirrhosis; however, the mechanisms of these effects are still unknown. The aim of the present study was to investigate the effects of chronic CB(1) (cannabinoid 1) receptor blockade in the hepatic microcirculation of CBL (common bile-duct-ligated) cirrhotic rats. After 1 week of treatment with AM251, a specific CB(1) receptor antagonist, IHR, SMA (superior mesenteric artery) blood flow and hepatic production of eicosanoids [TXB(2) (thromboxane B(2)), 6-keto PGF(1alpha) (prostaglandin F(1alpha)) and Cys-LTs (cysteinyl leukotrienes)] were measured. Additionally, the protein levels of hepatic COX (cyclo-oxygenase) isoforms, 5-LOX (5-lipoxygenase), CB(1) receptor, TGF-beta(1) (transforming growth factor beta(1)), cPLA(2) [cytosolic PLA(2) (phospholipase A(2))], sPLA(2) (secreted PLA(2)) and collagen deposition were also measured. In AM251-treated cirrhotic rats, a decrease in portal venous pressure was associated with the decrease in IHR and SMA blood flow. Additionally, the protein levels of hepatic CB(1) receptor, TGF-beta(1), cPLA(2) and hepatic collagen deposition, and the hepatic levels of 5-LOX and COX-2 and the corresponding production of TXB(2) and Cys-LTs in perfusates, were significantly decreased after 1 week of AM251 treatment in cirrhotic rats. Furthermore, acute infusion of AM251 resulted in a decrease in SMA blood flow and an increase in SMA resistance in CBL rats. In conclusion, the chronic effects of AM251 treatment on the intrahepatic microcirculation were, at least partly, mediated by the inhibition of hepatic TGF-beta(1) activity, which was associated with decreased hepatic collagen deposition and the activated PLA(2)/eicosanoid cascade in cirrhotic livers.
Collapse
Affiliation(s)
- Ying-Ying Yang
- Institute of Clinical Medicine, National Yang-Ming University School of Medicine, Taipei 11217, Taiwan
| | | | | | | | | | | | | | | |
Collapse
|
42
|
March S, Graupera M, Rosa Sarrias M, Lozano F, Pizcueta P, Bosch J, Engel P. Identification and functional characterization of the hepatic stellate cell CD38 cell surface molecule. THE AMERICAN JOURNAL OF PATHOLOGY 2007; 170:176-87. [PMID: 17200192 PMCID: PMC1762705 DOI: 10.2353/ajpath.2007.051212] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
The activation of hepatic stellate cells (HSCs) is a critical event in hepatic fibrosis, because these cells are the main producers of extracellular matrix proteins in the liver and contribute to the modulation of inflammatory responses via the secretion of several cytokines and the expression of adhesion molecules. The goal of the present study was to characterize cell surface proteins that regulate HSC activation. To this end, a panel of monoclonal antibodies (mAbs) was generated. mAb 14.27 recognized a protein of 45 kd that was highly expressed on HSCs. Affinity purification of this protein followed by sequencing revealed that protein to be CD38. We subsequently demonstrated that CD38 was constitutively expressed by HSCs and that its expression increased after in vitro and in vivo activation. mAb 14.27 induced an increase in cytosolic Ca2+ levels in HSCs, showing that it functions as an agonistic antibody. Moreover, the effects mediated by the CD38 mAb included induction of the proinflammatory cytokine interleukin-6 and up-regulation of the adhesion molecules intercellular adhesion molecule-1, vascular cell adhesion molecule-1, and neural cell adhesion molecule. Collectively, our data suggest that CD38 can act as a regulator of HSC activation and effector functions.
Collapse
Affiliation(s)
- Sandra March
- Immunology Unit, Department of Cellular Biology and Pathology, Medical School, University of Barcelona, Barcelona, Spain
| | | | | | | | | | | | | |
Collapse
|
43
|
Abstract
Animal models have allowed detailed study of hemodynamic alterations typical of portal hypertension and the molecular mechanisms involved in abnormalities in splanchnic and systemic circulation associated with this syndrome. Models of prehepatic portal hypertension can be used to study alterations in the splanchnic circulation and the pathophysiology of the hyperdynamic circulation. Models of cirrhosis allow study of the alterations in intrahepatic microcirculation that lead to increased resistance to portal flow. This review summarizes the currently available literature on animal models of portal hypertension and analyzes their relative utility. The criteria for choosing a particular model, depending on the specific objectives of the study, are also discussed.
Collapse
Affiliation(s)
- Juan-G Abraldes
- Liver Unit, Hospital Clinic, Villarroel 170, University of Barcelona 08036, Spain.
| | | | | |
Collapse
|
44
|
Abstract
Kupffer cells (KC) constitute 80-90% of the tissue macrophages present in the body. They reside within the lumen of the liver sinusoids, and are therefore constantly exposed to gut-derived bacteria, microbial debris and bacterial endotoxins, known to activate macrophages. Upon activation KC release various products, including cytokines, prostanoides, nitric oxide and reactive oxygen species. These factors regulate the phenotype of KC themselves, and the phenotypes of neighboring cells, such as hepatocytes, stellate cells, endothelial cells and other immune cells that traffic through the liver. Therefore, KC are intimately involved in the liver's response to infection, toxins, ischemia, resection and other stresses. This review summarizes established basic concepts of KC function as well as their role in the pathogenesis of various liver diseases.
Collapse
Affiliation(s)
- Manfred Bilzer
- Department of Medicine II, University of Munich, Klinikum Grosshadern, Munich, Germany.
| | | | | |
Collapse
|
45
|
Abstract
Animal models have allowed detailed study of hemodynamic alterations typical of portal hypertension and the molecular mechanisms involved in abnormalities in splanchnic and systemic circulation associated with this syndrome. Models of prehepatic portal hypertension can be used to study alterations in the splanchnic circulation and the pathophysiology of the hyperdynamic circulation. Models of cirrhosis allow study of the alterations in intrahepatic microcirculation that lead to increased resistance to portal flow. This review summarizes the currently available literature on animal models of portal hypertension and analyzes their relative utility. The criteria for choosing a particular model, depending on the specific objectives of the study, are also discussed.
Collapse
Affiliation(s)
- Juan-G Abraldes
- Liver Unit, Hospital Clinic, Villarroel 170, University of Barcelona 08036, Spain.
| | | | | |
Collapse
|
46
|
Matei V, Rodríguez-Vilarrupla A, Deulofeu R, Colomer D, Fernández M, Bosch J, Garcia-Pagán JC. The eNOS cofactor tetrahydrobiopterin improves endothelial dysfunction in livers of rats with CCl4 cirrhosis. Hepatology 2006; 44:44-52. [PMID: 16799985 DOI: 10.1002/hep.21228] [Citation(s) in RCA: 93] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
In cirrhosis, intrahepatic endothelial dysfunction is one of the mechanisms involved in the increased resistance to portal blood flow and therefore in the development of portal hypertension. Endothelial nitric oxide synthase (eNOS) uncoupling due to deficiency of tetrahydrobiopterin (BH4) results in decreased production of NO and plays a major role in endothelial dysfunction in other conditions. We examined whether eNOS uncoupling is involved in the pathogenesis of endothelial dysfunction of livers with cirrhosis. Basal levels of tetrahydrobiopterin and guanosine triphosphate (GTP)-cyclohydrolase (BH4 rate-limiting enzyme) expression and activity were determined in liver homogenates of control and rats with CCl4 cirrhosis. Thereafter, rats were treated with tetrahydrobiopterin, and eNOS activity, NO bioavailability, assessed with a functional assay, and the vasodilator response to acetylcholine (endothelial function) were evaluated. Livers with cirrhosis showed reduced BH4 levels and decreased GTP-cyclohydrolase activity and expression, which were associated with impaired vasorelaxation to acetylcholine. Tetrahydrobiopterin supplementation increased BH4 hepatic levels and eNOS activity and significantly improved the vasodilator response to acetylcholine in rats with cirrhosis. In conclusion, the impaired response to acetylcholine of livers with cirrhosis is modulated by a reduced availability of the eNOS cofactor, tetrahydrobiopterin. Tetrahydrobiopterin supplementation improved the endothelial dysfunction of cirrhotic livers.
Collapse
Affiliation(s)
- Vasilica Matei
- Hepatic Hemodynamic Laboratory, Liver Unit, Institut de Malalties Digestives i Metabòliques, Hospital Clínic, Institut d'Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), University of Barcelona, Barcelona, Spain
| | | | | | | | | | | | | |
Collapse
|
47
|
Hernández-Guerra M, García-Pagán JC, Turnes J, Bellot P, Deulofeu R, Abraldes JG, Bosch J. Ascorbic acid improves the intrahepatic endothelial dysfunction of patients with cirrhosis and portal hypertension. Hepatology 2006; 43:485-91. [PMID: 16496307 DOI: 10.1002/hep.21080] [Citation(s) in RCA: 97] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Patients with cirrhosis show intrahepatic endothelial dysfunction, characterized by an impaired flow-dependent vasorelaxation. This alteration is responsible for the marked postprandial increase in portal pressure and is attributed to an insufficient release of nitric oxide (NO). Ascorbic acid reverts endothelial dysfunction in other vascular disorders, via the increase of NO bioavailability through the neutralization of superoxide anions, thus preventing the scavenging of NO by superoxide. This study examined whether acute ascorbic acid administration might improve endothelial dysfunction in cirrhosis. Thirty-seven portal hypertensive patients with cirrhosis had measurements of hepatic and systemic hemodynamics, ascorbic acid, and malondialdehyde (MDA). Patients were randomly allocated to receive ascorbic acid (3 g, intravenously, n = 15) or placebo (n = 12) followed by a liquid meal. A third group received ascorbic acid followed by a sham meal (n = 10). Measurements were repeated after 30 minutes (hepatic venous pressure gradient at 15 and 30 minutes). Patients with cirrhosis had significantly lower ascorbic acid levels and higher MDA than healthy controls. Ascorbic acid significantly reduced MDA levels and markedly attenuated the postprandial increase in the hepatic venous pressure gradient (4% +/- 7% vs. 18% +/- 10% in placebo at 30 minutes, P < .001). Ascorbic acid followed by sham meal did not modify hepatic or systemic hemodynamics. In conclusion, patients with cirrhosis exhibited intrahepatic endothelial dysfunction, associated with decreased levels of ascorbic acid and increased levels of MDA. Ascorbic acid improved intrahepatic endothelial dysfunction, blunting the postprandial increase in portal pressure. These results encourage the performance of further studies testing antioxidants as adjunctive therapy in the treatment of portal hypertension.
Collapse
Affiliation(s)
- Manuel Hernández-Guerra
- Hepatic Hemodynamic Laboratory, Liver Unit, Institut de Malalties Digestives, Hospital Clinic, Institut d'Investigaciones Biomédiques August Pi i Sunyer, Barcelona, Spain
| | | | | | | | | | | | | |
Collapse
|
48
|
Turnes J, Hernández-Guerra M, Abraldes JG, Bellot P, Oliva R, García-Pagán JC, Bosch J. Influence of beta-2 adrenergic receptor gene polymorphism on the hemodynamic response to propranolol in patients with cirrhosis. Hepatology 2006; 43:34-41. [PMID: 16374847 DOI: 10.1002/hep.21000] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
The beta-2-adrenergic receptor (beta(2-)-AR) has several single-nucleotide polymorphisms. These influence the functional response to adrenergic stimulation; genotypes homozygous for Gly16-Glu27 or Gly16-Gln27 alleles (Gly16-Glu/Gln27 haplotypes) are associated with enhanced response, whereas genotypes homozygous for Arg16-Gln27 alleles (Arg16-Gln27) show a decreased response. We hypothesized that gene polymorphisms at the beta2-AR may influence the hemodynamic response to propranolol in patients with cirrhosis. The beta2-AR gene polymorphisms were determined by direct sequencing of the polymerase chain reaction (PCR) products in 48 patients with cirrhosis. All patients also had hepatic and systemic hemodynamic studies before and after propranolol administration. Prevalence of Gly16-Glu/Gln27 haplotypes was 29.1%, Arg16-Gln27 haplotype was 16.7%, and 54.2% were compound heterozygotes. Patients with cirrhosis with Gly16-Glu/Gln27 haplotypes had a greater decrease in heart rate, cardiac index, and hepatic blood flow after propranolol administration than those with Arg16-Gln27 haplotype. However, the HVPG response to propranolol was similar in both groups, whereas estimated hepatic sinusoidal resistance increased significantly in Gly16-Glu/Gln27 haplotypes but not in Arg16-Gln27 (+27.1 +/- 17.8% vs -17.9 +/- 13.9%, P = .042), suggesting that unopposed vasoconstrictive activity at the intrahepatic circulation hinders the fall in HVPG despite enhanced hemodynamic response to propranolol in Gly16-Glu/Gln27 haplotypes. In conclusion, beta2-AR gene polymorphisms influence the response to beta-blockade. However, HVPG reduction cannot be predicted from polymorphism analysis. Patients with the Gly16-Glu/Gln27 haplotypes may benefit from the association of hepatic vasodilators to propranolol therapy.
Collapse
Affiliation(s)
- Juan Turnes
- Hepatic Hemodynamic Laboratory, Institut de Malalties Digestives i Metaboliques, Hospital Clínic, IDIBAPS, Barcelona, Spain
| | | | | | | | | | | | | |
Collapse
|
49
|
Abraldes JG, García-Pagán JC. Modelos animales en el estudio de la hipertensión portal. GASTROENTEROLOGIA Y HEPATOLOGIA 2006; 29:51-9. [PMID: 16393631 DOI: 10.1157/13083254] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
Abstract
Animal models allow detailed study of the hemodynamic alterations in portal hypertension syndrome and of the molecular mechanisms involved in the abnormalities in splenic and systemic circulation associated with this syndrome. Models of prehepatic portal hypertension can be used to study alterations in the splenic circulation and the physiopathology of hyperdynamic circulation. Moreover, models of cirrhosis allow the alterations in intrahepatic microcirculation that lead to increased resistance to portal flow to be studied. The present review summarizes currently available animal models of portal hypertension and analyzes their relative utility in investigating the distinct disorders associated with this entity. The criteria for the choice of a particular model, depending on the specific objectives of the study, are also discussed.
Collapse
Affiliation(s)
- J G Abraldes
- Servicio de Hepatología, ICMDiM, Hospital Clínic, IDIBAPS, Universidad de Barcelona, Barcelona, Spain
| | | |
Collapse
|
50
|
Abstract
Portal hypertension (PHT) is responsible for the more severe and often lethal complications of cirrhosis such as bleeding oesophageal varices, ascites, renal dysfunction and hepatic encephalopathy. Because of the combined impact of these complications, PHT remains the most important cause of morbidity and mortality in patients with cirrhosis. Over the years, it has become clear that a decrease in portal pressure is not only protective against the risk of variceal (re)bleeding but is also associated with a lower long-term risk of developing complications and an improved long-term survival. A milestone in therapy was the introduction of non-selective beta-blockers for the prevention of bleeding and rebleeding of gastro-esophageal varices. However, in practice, less than half the patients under beta-blockade are protected from these risks, supporting the overall demand for innovation and expansion of our therapeutic armamentarium. Recent advances in the knowledge of the pathophysiology of cirrhotic PHT have directed future therapy towards the increased intrahepatic vascular resistance, which, in part, is determined by an increased hepatic vascular tone. This increased vasculogenic component provides the rationale for the potential use of therapies aimed at increasing intrahepatic vasorelaxing capacity via gene therapy, liver-selective nitric oxide donors and statines on the one hand, and at antagonizing excessive intrahepatic vasoconstrictor force through the use of endothelin antagonists, angiotensin blockers, alpha(1) adrenergic antagonists or combined alpha(1)- and non-selective beta-blockers or somatostatin analogues on the other. The focus of this review is to give an update on the pathophysiology of PHT in order to elucidate these potential novel strategies subsequently.
Collapse
Affiliation(s)
- Wim Laleman
- Department of Hepatology, University Hospital Gasthuisberg, Leuven, Belgium
| | | | | | | | | |
Collapse
|