Effect of valsartan on expression of leptin in rats with liver fibrosis

Background:Leptin may be involved in the formation and development of liver fibrosis.AngiotensinⅡtype 1 receptor(AT1R) antagonist can decrease the synthesis and secretion of leptin in adipose tissue in rats.Aims:To evaluate the effect of valsartan,an AT1R antagonist,on expression of leptin in rats with immunodamaged hepatic fibrosis.Methods: Thirty-six Sprague-Dawley rats were randomly divided into normal control group,model group and valsartan prevention group.In the latter two groups,liver fibrosis model was constructed by intraperitoneal injection with hog serum.Valsartan (30 mg/kg) was intragastrically administered daily after the construction of liver fibrosis in valsartan prevention group.At the 10th week,all the rats were sacrificed.The degree of fibrosis and collagen area were evaluated by HE and Sirius red staining.Expression of leptin was determined by immunohistochemistry staining.Results:As compared with normal control group,the degree of fibrosis(P0.05),collagen area(10.08%±2.01%vs.0.62%±0.31%,P0.01) and expression of liver tissue leptin(5.05±2.91 vs.0.44±0.27,P0.05) were obviously increased in model group.After intervention with valsartan,all the above-mentioned indices significantly ameliorated.Conclusions:Leptin can induce liver fibrosis,and AT1R antagonist valsartan can delay the development of liver fibrosis via the reduction of leptin expression in liver tissue, which may be one of the mechanisms of its anti-fibrosis effect.