RESUMO
Cirrhosis is a primary cause of liver-related mortality and morbidity. The basic process driving chronic liver disease to cirrhosis is accelerated fibrogenesis. Although the pathogenesis of liver cirrhosis is a multifactorial process, the essential step in the evolution of liver fibrosis is the activation of hepatic stellate cells, which are the main source of collagen produced in the extracellular matrix. This activation process is mediated by multiple growth factors, cytokines, and chemokines. One of the hepatic stellate cell-activating signaling molecules (and also one associated with cell injury and fibrosis) is osteopontin (OPN). OPN concentration in the plasma has been found to be predictive of liver fibrosis in various liver diseases. OPN concentrations correlate significantly with the stage of fibrosis, liver insufficiency, portal hypertension, and the presence of hepatocellular cancer. However, due to its versatile signaling functions, OPN not only contributes to the development of liver cirrhosis, but is also implicated in the pathogenesis of other chronic hepatic diseases such as viral hepatitis, both alcoholic and non-alcoholic steatohepatitis, drug-induced liver injury, and hepatocellular cancer. Thus, the targeting of OPN pathways seems to be a promising approach in the treatment of chronic liver diseases.
Assuntos
Hepatopatias/metabolismo , Osteopontina/metabolismo , Biomarcadores , Carcinoma Hepatocelular , Doença Hepática Induzida por Substâncias e Drogas/metabolismo , Insuficiência Hepática/metabolismo , Células Estreladas do Fígado/metabolismo , Humanos , Hipertensão Portal/metabolismo , Cirrose Hepática/metabolismo , Neoplasias Hepáticas/metabolismo , Hepatopatia Gordurosa não Alcoólica/metabolismo , Transdução de SinaisRESUMO
BACKGROUND: Heme oxygenase-1 (HMOX1) and bilirubin UDP-glucuronosyltransferase (UGT1A1), both enzymes involved in bilirubin homeostasis, play an important role in oxidative stress defense. OBJECTIVE: To assess the effect of promoter variations of HMOX1 and UGT1A1 genes on the progression of fibrosis in patients chronically infected with the hepatitis C virus (HCV). MATERIAL AND METHODS: The study was performed on146 chronic HCV infection patients, plus 146 age- and sex-matched healthy subjects. The (GT)n and (TA)n dinucleotide variations in HMOX1 and UGT1A1 gene promoters, respectively, were determined by fragment analysis in all subjects. RESULTS: No differences were found in the frequencies of each particular allele of both genes, between HCV patients and a control group (p > 0.05). Furthermore, no association was detected (p > 0.05) between either the HMOX1 or the UGT1A1 promoter variants and the individual histological stages of liver disease in the HCV positive patients. Finally, no differences in the HMOX1 and UGT1A1 genotype prevalence rates were found between pre-cirrhotic and cirrhotic patients (p > 0.05). CONCLUSION: Based on our data, microsatellite variations in the HMOX1 and UGT1A1 genes are not likely to protect from progression of liver disease in patients with chronic hepatitis C.
Assuntos
Variação Genética , Glucuronosiltransferase/genética , Heme Oxigenase-1/genética , Hepatite C Crônica/genética , Cirrose Hepática/genética , Fígado/enzimologia , Regiões Promotoras Genéticas , Biópsia , Estudos de Casos e Controles , República Tcheca , Frequência do Gene , Predisposição Genética para Doença , Hepacivirus/genética , Hepatite C Crônica/enzimologia , Hepatite C Crônica/patologia , Humanos , Fígado/patologia , Fígado/virologia , Cirrose Hepática/enzimologia , Cirrose Hepática/patologia , Cirrose Hepática/virologia , Repetições de Microssatélites , Fenótipo , RNA Viral/sangue , Carga ViralRESUMO
Administration of nonselective beta-blockers in prophylaxis of first variceal bleeding is not suitable for all patients. Thus, we evaluated endoscopic variceal band ligation (EVBL) in primary prevention of bleeding in patients with cirrhosis and large esophageal varices. A total of 73 consecutive patients with liver cirrhosis and large esophageal varices without a history of gastrointestinal bleeding were randomized to receive either EVBL or propranolol and were followed for up to 18 months. Forty patients underwent EVBL and 33 patients received propranolol. Variceal bleeding occurred in 2 patients in the EVBL (5%) and in 2 patients in the propranolol group (6%, NS). The 18 month actuarial risk for first variceal bleed was 5% in the EVBL (95% CI, 0-12%) and 20% in the propranolol group (95% CI, 0-49%, NS). The actuarial probability of death at 18 months of follow-up was 5% (95% CI, 0-11%) in the EVBL group and 7% (95% CI, 0-17%, NS) in the propranolol arm. In conclusion, EVBL was an effective and safe alternative to propranolol in primary prophylaxis of bleeding in patients with large esophageal varices.