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1.
Hepatology ; 75(3): 610-622, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-34716927

RESUMO

BACKGROUND AND AIMS: Liver fibrosis is the static and main (70%-80%) component of portal hypertension (PH). We investigated dynamic components of PH by a three-dimensional analysis based on correlation of hepatic collagen proportionate area (CPA) with portal pressure (PP) in animals or HVPG in patients. APPROACH AND RESULTS: Different animal models (bile duct ligation: n = 31, carbon tetrachloride: n = 12, thioacetamide: n = 12, choline-deficient high-fat diet: n = 12) and patients with a confirmed single etiology of cholestatic (primary biliary cholangitis/primary sclerosing cholangitis: n = 16), alcohol-associated (n = 22), and metabolic (NASH: n = 19) liver disease underwent CPA quantification on liver specimens/biopsies. Based on CPA-to-PP/HVPG correlation, potential dynamic components were identified in subgroups of animals/patients with lower-than-expected and higher-than-expected PP/HVPG. Dynamic PH components were validated in a patient cohort (n = 245) using liver stiffness measurement (LSM) instead of CPA. CPA significantly correlated with PP in animal models (Rho = 0.531; p < 0.001) and HVPG in patients (Rho = 0.439; p < 0.001). Correlation of CPA with PP/HVPG varied across different animal models and etiologies in patients. In models, severity of hyperdynamic circulation and specific fibrosis pattern (portal fibrosis: p = 0.02; septa width: p = 0.03) were associated with PH severity. In patients, hyperdynamic circulation (p = 0.04), vascular dysfunction/angiogenesis (VWF-Ag: p = 0.03; soluble vascular endothelial growth factor receptor 1: p = 0.03), and bile acids (p = 0.04) were dynamic modulators of PH. The LSM-HVPG validation cohort confirmed these and also indicated IL-6 (p = 0.008) and hyaluronic acid (HA: p < 0.001) as dynamic PH components. CONCLUSIONS: The relative contribution of "static" fibrosis on PH severity varies by type of liver injury. Next to hyperdynamic circulation, increased bile acids, VWF-Ag, IL-6, and HA seem to indicate a pronounced dynamic component of PH in patients.


Assuntos
Colágeno , Hipertensão Portal , Cirrose Hepática , Fígado , Pressão na Veia Porta/fisiologia , Animais , Biópsia/métodos , Depressores do Sistema Nervoso Central/farmacologia , Colestase/fisiopatologia , Colágeno/análise , Colágeno/metabolismo , Técnicas de Imagem por Elasticidade/métodos , Etanol/farmacologia , Hemodinâmica , Humanos , Hipertensão Portal/diagnóstico , Hipertensão Portal/etiologia , Hipertensão Portal/fisiopatologia , Fígado/diagnóstico por imagem , Fígado/metabolismo , Fígado/patologia , Fígado/fisiopatologia , Circulação Hepática , Cirrose Hepática/complicações , Cirrose Hepática/patologia , Cirrose Hepática/fisiopatologia , Modelos Animais , Ratos
2.
Liver Int ; 42(11): 2501-2512, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-35822301

RESUMO

BACKGROUND & AIMS: Experimental evidence indicates that systemic inflammation (SI) promotes liver fibrogenesis. This study investigated the potential link between SI and fibrogenesis in patients with advanced chronic liver disease (ACLD). METHODS: Serum biomarkers of SI (CRP, IL-6, procalcitonin [PCT]) and extracellular matrix (ECM) turnover (i.e., fibrogenesis/fibrolysis) were analysed in 215 prospectively recruited patients with ACLD (hepatic venous pressure gradient [HVPG] ≥6 mm Hg) undergoing hepatic vein catheterization. Patients with non-elective hospitalization or bacterial infection were excluded. Histological alpha-smooth muscle actin (α-SMA) area was quantified on full biopsy scans by automated morphometric quantification in a subset of 34 patients who underwent concomitant transjugular liver biopsy. RESULTS: Histological α-SMA proportionate area correlated with enhanced liver fibrosis (ELF) score (Spearman's ρ = 0.660, p < .001), markers of collagen formation (PRO-C3, ρ = 0.717, p < .001; PRO-C6, ρ = 0.526, p = .002) and tissue inhibitor of metalloproteinases-1 (TIMP1; ρ = 0.547, p < .001), indicating that these blood biomarkers are capable of reflecting the dynamic process of ECM turnover. CRP, IL-6 and PCT levels correlated with ELF, biomarkers of collagen synthesis/degradation and TIMP1, both in compensated and decompensated patients. Multivariate linear regression models (adjusted for HVPG) confirmed that CRP, IL-6 and PCT were independently linked to markers of liver fibrogenesis and ECM turnover. CONCLUSION: Systemic inflammation is linked to both liver fibrogenesis and ECM turnover in ACLD and this association is not confounded by the severity of liver disease, as evaluated by HVPG. Our study confirms experimental data on the detrimental impact of SI on ECM deposition and fibrosis progression in a thoroughly characterized cohort of patients with ACLD.


Assuntos
Actinas , Hepatopatias , Biomarcadores , Colágeno/análise , Colágeno/metabolismo , Complemento C3/análise , Humanos , Inflamação/patologia , Interleucina-6 , Fígado/patologia , Cirrose Hepática/complicações , Hepatopatias/complicações , Pró-Calcitonina , Inibidores Teciduais de Metaloproteinases
3.
Ann Intern Med ; 171(7): 453-457, 2019 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-31476765

RESUMO

Background: Microplastics are ubiquitous in natural environments. Ingestion of microplastics has been described in marine organisms, whereby particles may enter the food chain. Objective: To examine human feces for the presence of microplastics to determine whether humans involuntarily ingest them. Design: Prospective case series in which participants completed a food diary and sampled stool according to step-by-step instructions. Setting: Europe and Asia. Participants: Eight healthy volunteers aged 33 to 65 years. Measurements: After chemical digestion, Fourier-transform infrared microspectroscopy was used to analyze the presence and shape of 10 common types of microplastic in stool samples. Results: All 8 stool samples tested positive for microplastics. A median of 20 microplastics (50 to 500 µm in size) per 10 g of human stool were identified. Overall, 9 plastic types were detected, with polypropylene and polyethylene terephthalate being the most abundant. Limitations: There were few participants, and each provided only 1 sample. The origin and fate of microplastics in the gastrointestinal tract were not investigated. Conclusion: Various microplastics were detected in human stool, suggesting inadvertent ingestion from different sources. Further research on the extent of microplastic intake and the potential effect on human health is needed. Primary Funding Source: None.


Assuntos
Fezes/química , Microplásticos/análise , Adulto , Idoso , Ásia , Europa (Continente) , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Espectroscopia de Infravermelho com Transformada de Fourier
4.
Int J Mol Sci ; 21(6)2020 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-32188134

RESUMO

Molecular and cellular research modalities for the study of liver pathologies have been tremendously improved over the recent decades. Advanced technologies offer novel opportunities to establish cell isolation techniques with excellent purity, paving the path for 2D and 3D microscopy and high-throughput assays (e.g., bulk or single-cell RNA sequencing). The use of stem cell and organoid research will help to decipher the pathophysiology of liver diseases and the interaction between various parenchymal and non-parenchymal liver cells. Furthermore, sophisticated animal models of liver disease allow for the in vivo assessment of fibrogenesis, portal hypertension and hepatocellular carcinoma (HCC) and for the preclinical testing of therapeutic strategies. The purpose of this review is to portray in detail novel in vitro and in vivo methods for the study of liver cell biology that had been presented at the workshop of the 8th meeting of the European Club for Liver Cell Biology (ECLCB-8) in October of 2018 in Bonn, Germany.


Assuntos
Biologia Celular , Técnicas Citológicas/métodos , Fígado/patologia , Animais , Carcinoma Hepatocelular/patologia , Comunicação Celular , Técnicas de Cultura de Células , Modelos Animais de Doenças , Fígado Gorduroso/patologia , Expressão Gênica , Alemanha , Hepatócitos/patologia , Humanos , Hipertensão Portal/patologia , Neoplasias Hepáticas/patologia , Hepatopatia Gordurosa não Alcoólica/patologia , Organoides/patologia
5.
Semin Liver Dis ; 39(4): 483-501, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31315135

RESUMO

Portal hypertension is the main driver for severe complications in patients with liver cirrhosis. With improved understanding of molecular pathways that promote hepatic vascular remodeling, vasoconstriction, and sinusoidal capillarization potential vascular targets for the treatment of portal hypertension have been identified. Inhibition of vascular endothelial and platelet-derived growth factors-driven angiogenesis has been shown to reduce portal pressure and decrease hepatic inflammation. Angiopoietin/Tie signaling represents additional promising vascular targets in liver disease. The eNOS-NO-sGC-cGMP pathway modulates sinusoidal vasoconstriction and capillarization. Nuclear farnesoid X receptor (FXR) agonists decrease intrahepatic vascular resistance by inhibition of fibrogenesis and sinusoidal remodeling. Statins ameliorate endothelial dysfunction, decrease portal pressure, and reduce fibrogenesis. Anticoagulation with low-molecular heparin or anti-Xa inhibitors improved portal hypertension by deactivation of hepatic stellate cells and potentially via reduction of sinusoidal microthrombosis. This review summarizes important vascular targets for treatment of portal hypertension that have shown promising results in experimental studies.


Assuntos
Hipertensão Portal/terapia , Anticoagulantes/uso terapêutico , GMP Cíclico/metabolismo , Humanos , Inibidores de Hidroximetilglutaril-CoA Redutases/uso terapêutico , Hipertensão Portal/fisiopatologia , Neovascularização Patológica/fisiopatologia , Neovascularização Patológica/prevenção & controle , Óxido Nítrico/metabolismo , Receptores Citoplasmáticos e Nucleares/agonistas , Guanilil Ciclase Solúvel/metabolismo
6.
Dig Liver Dis ; 2024 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-39343656

RESUMO

BACKGROUND: Cirrhosis is associated with a proinflammatory environment. AIMS: To analyse aetiology-specific inflammation patterns in compensated cirrhosis in animal models and patients. METHODS: Portal pressure (PP), fibrosis (collagen proportionate area [CPA]) and hepatic inflammation were measured in cirrhotic rat models (thioacetamide [TAA;n = 12]; choline-deficient high-fat diet [CDHFD;n = 12]; bile duct ligation [BDL;n = 16]). Compensated cirrhotic patients (alcohol-related liver disease [ALD;n = 67]; metabolic dysfunction-associated steatohepatitis [MASH;n = 50]; cholestatic liver disease [primary biliary cholangitis [PBC]/primary sclerosing cholangitis [PSC];n = 22]) undergoing hepatic venous pressure gradient (HVPG) measurement were included. RESULTS: In rats, hepatic proinflammatory gene expression was highest in CDHFD and lowest in TAA, despite comparable PP levels. Across all animal models, Tnfa/Il6 correlated positively with CPA, and Mcp1 with elevated PP. Mcp1 was also associated with increased CPA in TAA/CDHFD. Mcp1/Cxcl1 showed a model-independent positive correlation to transaminases. Il1b correlated positively with CPA/PP in BDL and with transaminases in CDHFD. In patients, CRP/IL-6 were lower in MASH compared to ALD or PBC/PSC, regardless of hepatic function. IgA/IgG were highest and complement factors lowest in ALD. More pronounced systemic inflammation was linked to higher HVPG primarily in ALD/MASH. CONCLUSION: Proinflammatory pathways are upregulated across all liver disease aetiologies, yet their association with fibrosis and portal hypertension can vary.

7.
iScience ; 27(3): 109301, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38469563

RESUMO

Persistent liver injury triggers a fibrogenic program that causes pathologic remodeling of the hepatic microenvironment (i.e., liver fibrosis) and portal hypertension. The dynamics of gene regulation during liver disease progression and early regression remain understudied. Here, we generated hepatic transcriptome profiles in two well-established liver disease models at peak fibrosis and during spontaneous regression after the removal of the inducing agents. We linked the dynamics of key disease readouts, such as portal pressure, collagen area, and transaminase levels, to differentially expressed genes, enabling the identification of transcriptomic signatures of progressive vs. regressive liver fibrosis and portal hypertension. These candidate biomarkers (e.g., Tcf4, Mmp7, Trem2, Spp1, Scube1, Islr) were validated in RNA sequencing datasets of patients with cirrhosis and portal hypertension, and those cured from hepatitis C infection. Finally, deconvolution identified major cell types and suggested an association of macrophage and portal hepatocyte signatures with portal hypertension and fibrosis area.

8.
Cell Mol Gastroenterol Hepatol ; 16(5): 847-856, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37572734

RESUMO

BACKGROUND & AIMS: Glucagon-like peptide (GLP)-2 may exert antifibrotic effects on hepatic stellate cells (HSCs). Thus, we aimed to test whether application of the GLP-2 analogue teduglutide has hepatoprotective and antifibrotic effects in the Mdr2/Abcb4-/- mouse model of sclerosing cholangitis displaying hepatic inflammation and fibrosis. METHODS: Mdr2-/- mice were injected daily for 4 weeks with teduglutide followed by gene expression profiling (bulk liver; isolated HSCs) and immunohistochemistry. Activated HSCs (LX2 cells) and immortalized human hepatocytes and human intestinal organoids were treated with GLP-2. mRNA profiling by reverse transcription polymerase chain reaction and electrophoretic mobility shift assay using cytosolic and nuclear protein extracts was performed. RESULTS: Hepatic inflammation, fibrosis, and reactive cholangiocyte phenotype were improved in GLP-2-treated Mdr2-/- mice. Primary HSCs isolated from Mdr2-/- mice and LX2 cells exposed to GLP-2 in vitro displayed significantly increased mRNA expression levels of NR4a1/Nur77 (P < .05). Electrophoretic mobility shift assay revealed an increased nuclear NR4a1 binding after GLP-2 treatment in LX2 cells. Moreover, GLP-2 alleviated the Tgfß-mediated reduction of NR4a1 nuclear binding activity. In vivo, GLP-2 treatment of Mdr2-/- mice resulted in increased intrahepatic levels of muricholic acids (accordingly Cyp2c70 mRNA expression was significantly increased), and in reduced mRNA levels of Cyp7a1 and FXR. Serum Fgf15 levels were increased in Mdr2-/- mice treated with GLP-2. Accordingly, GLP-2 treatment of human intestinal organoids activated their FXR-FGF19 signaling axis. CONCLUSIONS: GLP-2 treatment increased NR4a1/Nur77 activation in HSCs, subsequently attenuating their activation. GLP-2 promoted intestinal Fxr-Fgf15/19 signaling resulting in reduced Cyp7a1 and increased Cyp2c70 expression in the liver, contributing to hepatoprotective and antifibrotic effects of GLP-2 in the Mdr2-/- mouse model.


Assuntos
Células Estreladas do Fígado , Cirrose Hepática , Camundongos , Humanos , Animais , Células Estreladas do Fígado/metabolismo , Camundongos Knockout , Cirrose Hepática/tratamento farmacológico , Cirrose Hepática/metabolismo , Modelos Animais de Doenças , RNA Mensageiro/metabolismo , Inflamação/metabolismo
9.
Hepatol Int ; 17(4): 1045-1056, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-36881247

RESUMO

BACKGROUND: Experimental data suggest that bacterial translocation (BT) promotes systemic inflammation, portal hypertension, and circulatory dysfunction in advanced chronic liver disease (ACLD). METHODS: Patients with ACLD undergoing hepatic venous pressure gradient (HVPG) measurement and absence of acute decompensation or infections were included (n = 249). Serum biomarkers of BT (lipopolysaccharide [LPS], lipoteichoic acid [LTA], bacterial DNA [bactDNA]), systemic inflammation and markers of circulatory dysfunction were assessed. T-cell subsets in intestinal biopsies (n = 7 ACLD, n = 4 controls) were analyzed by flow cytometry. RESULTS: Patients had a median HVPG of 18 (12-21) mmHg and 56% had decompensated ACLD. LPS (0.04 [0.02-0.06] vs. 0.64 [0.30-1.06] EU/mL), LTA (4.53 [3.58-5.97] vs. 43.2 [23.2-109] pg/mL), and detection of bactDNA (≥ 5 pg/mL; 5% vs. 41%) were markedly higher in patients with ACLD than healthy controls (n = 40; p < 0.001) but were similar between different clinical stages of compensated and decompensated ACLD and displayed no meaningful correlation with HVPG and systemic hemodynamics. TNF-α and IL-10 correlated with LPS (Spearman's rs = 0.523, p < 0.001/rs = 0.143, p = 0.024) but not with LTA. Presence of bactDNA was associated with higher LPS (0.54 [0.28-0.95] vs. 0.88 [0.32-1.31] EU/mL, p = 0.001) and TNF-α (15.3 [6.31-28.1] vs. 20.9 [13.8-32.9] pg/mL). Patients with ACLD exhibited a decreased CD4:CD8-ratio and increased TH1-cells in the intestinal mucosa as compared to controls. During a median FU of 14.7 (8.20-26.5) months, bacterial antigens did not predict decompensation or liver-related death (in contrast to HVPG, IL-6, and MAP) as well as infections at 24 months. CONCLUSION: BT occurs already in early ACLD stages and triggers a systemic inflammatory response via TNF-α and IL-10. Interestingly, BT markers showed no clear correlation with portal hypertension and circulatory dysfunction in patients with stable ACLD. CLINICAL TRIAL NUMBER: NCT03267615.


Assuntos
Hipertensão Portal , Lipopolissacarídeos , Humanos , Interleucina-10 , Translocação Bacteriana , Fator de Necrose Tumoral alfa , Cirrose Hepática/complicações , Hipertensão Portal/complicações , Inflamação , Pressão na Veia Porta
10.
Adv Med Sci ; 67(1): 154-162, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35272246

RESUMO

PURPOSE: Portal hypertension (PH)-associated splenomegaly is caused by portal venous congestion and splanchnic hyperemia. This can trigger hypersplenism, which favors the development of cytopenia. We investigated the time-dependent impact of splenectomy on portal pressure and blood cell counts in animal models of non-cirrhotic and cirrhotic PH. MATERIALS AND METHODS: Ninety-six rats underwent either partial portal vein ligation (PPVL), bile duct ligation (BDL), or sham operation (SO), with subgroups undergoing additional splenectomy. Portal pressure, mean arterial pressure, heart rate, blood cell counts and hemoglobin concentrations were evaluated throughout 5 weeks following surgery. RESULTS: Following PPVL or BDL surgery, the animals presented a progressive rise in portal pressure, paralleled by decreased mean arterial pressure and accelerated heart rate. Splenectomy curbed the development of PH in both models (PPVL: 16.25 vs. 17.93 â€‹mmHg, p â€‹= â€‹0.083; BDL: 13.55 vs. 15.23 â€‹mmHg, p â€‹= â€‹0.028), increased mean arterial pressure (PPVL: +7%; BDL: +9%), and reduced heart rate (PPVL: -10%; BDL: -13%). Accordingly, splenectomized rats had lower von Willebrand factor plasma levels (PPVL: -22%; BDL: -25%). Splenectomy resulted in higher hemoglobin levels in PPVL (14.15 vs. 13.08 â€‹g/dL, p â€‹< â€‹0.001) and BDL (13.20 vs. 12.39 â€‹g/dL, p â€‹= â€‹0.097) animals, and significantly increased mean corpuscular hemoglobin concentrations (PPVL: +9%; BDL: +15%). Thrombocytopenia only developed in the PPVL model and was alleviated in the splenectomized subgroup. Conversely, BDL rats presented with thrombocytosis, which was not affected by splenectomy. CONCLUSIONS: Splenectomy improves both cirrhotic and non-cirrhotic PH, and ameliorates the hyperdynamic circulation. Hypersplenism related anemia and thrombocytopenia were only significantly improved in the non-cirrhotic PH model.


Assuntos
Anemia , Hipertensão Portal , Anemia/complicações , Animais , Modelos Animais de Doenças , Hipertensão Portal/complicações , Ligadura/efeitos adversos , Cirrose Hepática/complicações , Cirrose Hepática/cirurgia , Pressão na Veia Porta , Ratos , Esplenectomia/efeitos adversos
11.
Biochim Biophys Acta Mol Basis Dis ; 1867(12): 166235, 2021 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-34339839

RESUMO

Nuclear receptors are ligand-activated transcription factors that regulate gene expression of a variety of key molecular signals involved in liver fibrosis. The primary cellular driver of liver fibrogenesis is activated hepatic stellate cells. Different nuclear receptors regulate the hepatic expression of pro-inflammatory and pro-fibrogenic cytokines that promote the transformation of hepatic stellate cells into fibrogenic myofibroblasts. Importantly, nuclear receptors regulate gene expression circuits that promote hepatic fibrogenesis and/or allow liver fibrosis regression. In this review, we highlight the direct and indirect influence of nuclear receptors on liver fibrosis, with a focus on hepatic stellate cells, and discuss potential therapeutic effects of nuclear receptor modulation in regard to anti-fibrotic and anti-inflammatory effects. Further research on nuclear receptors-related signaling may lead to the clinical development of effective anti-fibrotic therapies for patients with liver disease.


Assuntos
Cirrose Hepática/genética , Fígado/metabolismo , Receptores Citoplasmáticos e Nucleares/genética , Regulação da Expressão Gênica/genética , Células Estreladas do Fígado/metabolismo , Células Estreladas do Fígado/patologia , Humanos , Ligantes , Fígado/patologia , Cirrose Hepática/patologia , Miofibroblastos/metabolismo , Transdução de Sinais/genética , Fatores de Transcrição/genética
12.
Biomedicines ; 9(1)2021 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-33435509

RESUMO

BACKGROUND: The farnesoid X receptor (FXR) influences hepatic metabolism, inflammation and liver fibrosis as key components of non-alcoholic steatohepatitis (NASH). We studied the effects of the non-steroidal FXR agonist cilofexor (formerly GS-9674) on portal pressure and fibrosis in experimental NASH. METHODS: NASH was induced in Wistar rats using a choline-deficient high-fat diet plus intraperitoneal sodium nitrite injections. First, a dose-finding study was performed with 10 mg/kg and 30 mg/kg of cilofexor, focusing on histological readouts. Liver fibrosis was assessed by Picro-Sirius-Red, desmin staining and hepatic hydroxyproline content. Gene expression was determined by RT-PCR. In a subsequent hemodynamic study, rats received 30 mg/kg cilofexor with or without propranolol (25 mg/kg). Portal pressure, systemic hemodynamics and splanchnic blood flow were measured. RESULTS: Cilofexor dose-dependently induced FXR target genes shp, cyp7a1 and fgf15 in hepatic and ileal tissues, paralleled by a dose-dependent reduction in liver fibrosis area (Picro-Sirius-Red) of -41% (10 mg/kg) and -69% (30 mg/kg), respectively. The 30 mg/kg cilofexor dose significantly reduced hepatic hydroxyproline content (-41%), expression of col1a1 (-37%) and pdgfr-ß (-36%), as well as desmin area (-42%) in NASH rats. Importantly, cilofexor decreased portal pressure (11.9 ± 2.1 vs. 8.9 ± 2.2 mmHg; p = 0.020) without affecting splanchnic blood-flow or systemic hemodynamics. The addition of propranolol to cilofexor additionally reduced splanchnic inflow (-28%) but also mean arterial pressure (-25%) and heart rate (-37%). CONCLUSION: The non-steroidal FXR agonist cilofexor decreased portal hypertension and reduced liver fibrosis in NASH rats. While cilofexor seems to primarily decrease sinusoidal resistance in cirrhotic portal hypertension, the combination with propranolol additionally reduced mesenteric hyperperfusion.

13.
United European Gastroenterol J ; 8(10): 1174-1185, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-32878579

RESUMO

BACKGROUND: In cirrhosis, the nitric oxide-soluble guanylyl cyclase (sGC)-cyclic guanosine monophosphate (cGMP) pathway is impaired, which contributes to increased intrahepatic vascular resistance (IHVR) and fibrogenesis. We investigated if sGC stimulation (riociguat (RIO)), sGC activation (cinaciguat (CINA)) or phosphodiesterase (PDE)-5 inhibition (tadalafil (TADA)) improves portal hypertension (PHT) and liver fibrosis. METHODS: Fifty male Sprague-Dawley rats underwent bile-duct ligation (BDL) or sham operation. RIO (0.5 mg/kg), CINA (1 mg/kg), TADA (1.5 mg/kg) or vehicle (VEH) was administered from weeks 2 to 4 after BDL. At week 4, invasive haemodynamic measurements were performed, and liver fibrosis was assessed by histology (chromotrope-aniline blue (CAB), Picro-Sirius red (PSR)) and hepatic hydroxyproline content. RESULTS: Cirrhotic bile duct-ligated rats presented with PHT (13.1 ± 1.0 mmHg) and increased IHVR (4.9 ± 0.5 mmHg⋅min/mL). Both RIO (10.0 ± 0.7 mmHg, p = 0.021) and TADA (10.3 ± 0.9 mmHg, p = 0.050) decreased portal pressure by reducing IHVR (RIO: -41%, p = 0.005; TADA: -21%, p = 0.199) while not impacting heart rate, mean arterial pressure and portosystemic shunting. Hepatic cGMP levels increased upon RIO (+239%, p = 0.006) and TADA (+32%, p = 0.073) therapy. In contrast, CINA dosed at 1 mg/kg caused weight loss, arterial hypotension and hyperlactataemia in bile duct-ligated rats. Liver fibrosis area was significantly decreased by RIO (CAB: -48%, p = 0.011; PSR: -27%, p = 0.121) and TADA (CAB: -21%, p = 0.342; PSR: -52%, p = 0.013) compared to VEH-treated bile duct-ligated rats. Hepatic hydroxyproline content was reduced by RIO (from 503 ± 20 to 350 ± 30 µg/g, p = 0.003) and TADA (282 ± 50 µg/g, p = 0.003), in line with a reduction of the hepatic stellate cell activation markers smooth-muscle actin and phosphorylated moesin. Liver transaminases decreased under RIO (AST: -36%; ALT: -32%) and TADA (AST: -24%; ALT: -27%) treatment. Hepatic interleukin 6 gene expression was reduced in the RIO group (-56%, p = 0.053). CONCLUSION: In a rodent model of biliary cirrhosis, the sGC stimulator RIO and the PDE-5 inhibitor TADA improved PHT. The decrease of sinusoidal vascular resistance was paralleled by a reduction in liver fibrosis and hepatic inflammation, while systemic haemodynamics were not affected.


Assuntos
Hipertensão Portal/tratamento farmacológico , Cirrose Hepática/tratamento farmacológico , Inibidores da Fosfodiesterase 5/uso terapêutico , Guanilil Ciclase Solúvel/antagonistas & inibidores , Animais , Benzoatos/farmacologia , Benzoatos/uso terapêutico , Ductos Biliares/cirurgia , Modelos Animais de Doenças , Humanos , Hipertensão Portal/diagnóstico , Hipertensão Portal/etiologia , Hipertensão Portal/fisiopatologia , Ligadura/efeitos adversos , Cirrose Hepática/etiologia , Masculino , Inibidores da Fosfodiesterase 5/farmacologia , Pressão na Veia Porta/efeitos dos fármacos , Pressão na Veia Porta/fisiologia , Sistema Porta/efeitos dos fármacos , Sistema Porta/fisiopatologia , Pirazóis/farmacologia , Pirazóis/uso terapêutico , Pirimidinas/farmacologia , Pirimidinas/uso terapêutico , Ratos , Ratos Sprague-Dawley , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/fisiologia , Guanilil Ciclase Solúvel/metabolismo , Tadalafila/farmacologia , Tadalafila/uso terapêutico , Resistência Vascular/efeitos dos fármacos , Resistência Vascular/fisiologia
14.
J Vis Exp ; (138)2018 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-30124644

RESUMO

This is a detailed protocol describing invasive hemodynamic measurements in cirrhotic rats for the characterization of portal hypertensive syndrome. Portal hypertension (PHT) due to cirrhosis is responsible for the most severe complications in patients with liver disease. The full picture of the portal hypertensive syndrome is characterized by increased portal pressure (PP) due to the increased intrahepatic vascular resistance (IHVR), hyperdynamic circulation, and increased splanchnic blood flow. Progressive splanchnic arterial vasodilation and increased cardiac output with elevated heart rate (HR) but low arterial pressure characterizes the portal hypertensive syndrome. Novel therapies are currently being developed that aim to decrease PP by either targeting IHVR or increased splanchnic blood flow - but side effects on systemic hemodynamics may occur. Thus, a detailed characterization of portal venous, splanchnic, and systemic hemodynamic parameters, including measurement of PP, portal venous blood flow (PVBF), mesenteric arterial blood flow, mean arterial pressure (MAP), and HR is needed for preclinical evaluation of the efficacy of novel treatments for PHT. Our video article provides the reader with a structured protocol for performing invasive hemodynamic measurements in cirrhotic rats. In particular, we describe the catheterization of the femoral artery and the portal vein via an ileocolic vein and the measurement of portal venous and splanchnic blood flow via perivascular Doppler-ultrasound flow probes. Representative results of different rat models of PHT are shown.


Assuntos
Hemodinâmica/fisiologia , Hipertensão Portal/etiologia , Cirrose Hepática/complicações , Animais , Hipertensão Portal/patologia , Masculino , Ratos , Ratos Sprague-Dawley
15.
Sci Rep ; 8(1): 9372, 2018 06 19.
Artigo em Inglês | MEDLINE | ID: mdl-29921982

RESUMO

In cirrhotic patients, portal hypertension (PHT) deteriorates survival, yet treatment options are limited. A major contributor to increased intrahepatic vasoconstriction in PHT is dysfunctional nitric-oxide signaling. Soluble guanylate cyclase (sGC) is the receptor of nitric-oxide and can be stimulated by riociguat. Riociguat is approved for pulmonary hypertension but has not been studied in liver cirrhosis. In this study we assessed the effects of riociguat on PHT and liver fibrosis in cholestatic (bile duct ligation, BDL) and toxic (carbon-tetrachloride, CCl4) rat models. In cirrhotic livers sGC expression was upregulated. In BDL rats, riociguat reduced liver fibrosis and decreased portal pressure without affecting systemic hemodynamics. In an early BDL disease stage, riociguat decreased bile duct proliferation, improved sinusoidal vascular dysfunction and inhibited angiogenesis. In advanced BDL riociguat exhibited anti-inflammatory effects. In CCl4 rats the beneficial effects of riociguat treatment were less pronounced and confined to an early disease stage. Similarly, in patients with cholestatic cirrhosis and PHT nitrates (that induce sGC activity) decreased portal pressure more effectively than in patients with non-cholestatic etiology. We also found an improvement of transaminases in patients with pulmonary hypertension receiving riociguat. Our findings support the clinical development of sGC stimulators in patients with cirrhotic PHT.


Assuntos
Cirrose Hepática/tratamento farmacológico , Cirrose Hepática/enzimologia , Pirazóis/uso terapêutico , Pirimidinas/uso terapêutico , Guanilil Ciclase Solúvel/metabolismo , Animais , Hemodinâmica/efeitos dos fármacos , Humanos , Hipertensão Portal/tratamento farmacológico , Hipertensão Portal/enzimologia , Masculino , Ratos , Ratos Sprague-Dawley
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