Dynamic changes of integrin α5β1 in the development of liver fibrosis and the effects of Fuzheng Huayu decoction

Objective To investigate the dynamic changes of integrin α5β1 during the process of liver fibrosis, and the effects of Fuzheng Huayu (improving vital energe and dissolving stasis-Chinese medical theray) decoction on liver fibrosis. Methods Liver fibrosis was induced in rats by injection of CCl 4 subcutaneously and fed with high lipid and lower protein diet. Rats were divided into 3 groups: normal, model control and Fuzheng Huayu decoction treated group. In the model controls, rats were sacrified at 2 d, 1 w, 2 w, 3 w, 4 w, 5 w and 6 w. For the treated group, rats were adminstered with Fuzheng Huayu decoction by gavage from the beginning of the study, and continue to 6 week. Rats were also sacrified at 6 different time as abovementioned. Collagen deposition in liver was studied by Sirius red staining. The contents of hepatic hydroxy proline (Hyp) were measured with Jamall's methods. Protein expressions of fibronectin(FN), integrin α5β1 and α smooth muscle actin (SMA) in liver tissue were tested with Western blot, and the correlations among them were analyzed with SPSS 11.0 statistical software.Results The expressions of α SMA, FN and α5β1 increased gradually as liver fibrosis developed. At the early stage, FN increased markedly, and later α5β1 and α SMA increased significantly. There were significantly positively correlations among FN, α5β1 and α SMA. Fuzheng Huayu decoction markedly attenuated collagen deposition, decreased Hyp contents and the expressions of FN, α5β1 and α SMA.Conclusions Expressions of integrin α5β1 increase gradually in the process of liver fibrosis. FN increase significantly in the early stage of hepatic injury, which may promote the activation of hepatic stellate cells through integrin α5β1 signal pathway. Fuzheng Huayu decoction can decrease the expressions of FN and integrin α5β1 in rat hepatic fibrosis model, which may relate to the mechanisms of anti fibrosis in Chinese medical theory of improving vital energe and dissolving stasis.