Although the time between biopsies partly affected the patient's clinical course, the differences observed here suggest that in patients with chronic hepatitis C, regression of fibrosis is associated with sustained virologic response to interferon therapy.
Effects of antioxidants, resveratrol, quercetin, and N-acetylcysteine (NAC) on the functions of cultured rat hepatic stellate cells and Kupffer cells were studied. These compounds dose-dependently suppressed serum-dependent proliferation of stellate cells as determined by [ 3 H]thymidine and 5-bromo-2Ј-deoxyuridine uptake. Expression of smooth muscle ␣-actin was suppressed by a high dose of resveratrol and quercetin. These phenolic compounds also suppressed inositol phosphate metabolism, tyrosine phosphorylation, and mitogen-activated protein (MAP) kinase activation in platelet-derived growth factor/BB-stimulated stellate cells. Moreover, the phenolic compounds selectively reduced the level of cell cycle protein cyclin D1 in stellate cells. Thus, resveratrol and quercetin might inhibit stellate cell activation by perturbing signal transduction pathway and cell cycle protein expression, whereas mechanism of potent antiproliferative effect of NAC remains to be elucidated. On the other hand, kinetic analysis showed that production of nitric oxide (NO) and tumor necrosis factor ␣ (TNF-␣) by lipopolysaccharide-stimulated Kupffer cells was strongly inhibited by resveratrol and quercetin but not by NAC. Although expression of messenger RNAs for inducible NO synthase and TNF-␣ was not affected by the phenolic compounds, cellular levels of inducible NO synthase and TNF-␣ secretion were suppressed significantly, indicating the posttranscriptional process of generating these proteins might be affected predominantly by these phenolic compounds. Thus, NAC and these phenolic compounds may have therapeutic potential against liver injury by regulating functions of hepatic stellate cells and Kupffer
We prospectively monitored 140 cirrhotic patients for the development of hepatocellular carcinoma for 6 yr, using periodical screening by high-resolution convex-array ultrasonography and alpha-fetoprotein. Twenty-eight patients were positive for HBs antigen, 26 patients had received blood transfusions and were negative for HBs antigen and 26 patients had a history of heavy drinking. We detected hepatocellular carcinoma in 40 patients during this period. The overall cumulative incidence of hepatocellular carcinoma in the 6 yr was 39%; the cumulative incidence was 59% in patients with HBsAg, 53% in patients who had had blood transfusions and were negative for HBsAg and 22% in patients who had a history of heavy drinking and who were without HBsAg. Detection of the carcinoma in 85% of these 40 patients was based on results of ultrasonography. Twenty-six of the patients (65%) had a small hepatocellular carcinoma of 2 cm or less. alpha-Fetoprotein levels were lower than 100 ng/ml in 56% of these 40 patients. Patients with cirrhosis are at high risk of developing hepatocellular carcinoma, especially patients with HBsAg or with a history of blood transfusion who are negative for HBsAg. Periodic monitoring by use of ultrasonography in particular is recommended for early detection of hepatocellular carcinoma.
Proteome analysis was performed on cellular and secreted proteins of normal (quiescent) and activated rat hepatic stellate cells. The stellate cells were activated either in vitro by cultivating quiescent stellate cells for 9 days or in vivo by injecting rats with carbon tetrachloride for 8 weeks. A total of 43 proteins/polypeptides were identified, which altered their expression levels when the cells were activated in vivo and/or in vitro. Twenty-seven of them showed similar changes in vivo and in vitro, including up-regulated proteins such as calcyclin, calgizzarin, and galectin-1 as well as down-regulated proteins such as liver carboxylesterase 10 and serine protease inhibitor 3. Sixteen of them showed different expression levels between in vivo and in vitro activated stellate cells. These results were reproducibly obtained in 3 independent experiments. The up-regulation of calcyclin, calgizzarin, and galectin-1, as well as the down-regulation of liver carboxylesterase 10 were directly confirmed in fibrotic liver tissues. Northern blots confirmed up-regulation of the messenger RNAs (mRNAs) of calcyclin, calgizzarin, and galectin-1 in activated stellate cells, indicating that these changes were controlled at the mRNA level. In addition a list compiling over 150 stellate cell proteins is presented. The data presented here thus provide a significant new protein-level insight into the activation of hepatic stellate cells, a key event in liver fibrogenesis.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.