Molecular mechanism of the effect of Y27632,an antagonist of ROCK,depressing liver fibrosis

Objective To discuss the molecular mechanism of Y27632,an antagonist of ROCK,depressing liver fibrosis through observing the expression of extracellular martrix,RhoA and Vinculin mRNA,RhoA and MLC protein.Methods Thirty male SD rats were randomly divided into control group,model group and treatment group.Liver fibrotic model was made by subcutaneous injection of CCl4,and Y27632(30 mg/Kg) was given orally everyday in treatment group after the 4th week.Liver tissue and blood samples were taken after the 8th week.The degree of liver fibrosis was evaluated by V-G staining,and the PⅢP and Ⅳ collagen were detected by RI.Other 30 male SD rats were divided into control group and model group.Hepatic stellate cells were isolated from the model group.The model group may be divided into non-intervention group(n=10) and intervention group(n=10).Intervention group was given Y27632 which the final concentration was 50 μmol/L.Cell morphology was observed and all culture cells were harvested after 1 h.RT-PCR was used to detect the expression of Vinculin and RhoA mRNA,Western blotting was used to detect the expression of RhoA and MLC protein.Results Compared with model group, the organic pathology showed the degree of liver fibrosis alleviated in treatment group,contents of PⅢP and Ⅳ collagen decreased markedly in treatment group.Expression of RhoA,Vinculin mRNA and RhoA protein in non-intervention group were stronger than those in control group,and decreased markedly in intervention group.Expression of MLC protein decreased markedly in non-intervention group,and increased in intervention group.Conclusion Y27632 can alleviate the degree of liver fibrosis by blockade RhoA signaling transduction pathway.