肝纤维化过程中整合素α5β1动态变化与扶正化瘀方干预作用

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

目的 探讨肝纤维化形成过程中整合素α5 β1蛋白的变化特点 ,及其扶正化瘀方影响该蛋白表达的抗肝纤维化作用机制。方法 四氯化碳 (CCl4)皮下注射与高脂低蛋白饲料复合建立大鼠肝纤维化模型。 13 5只大鼠分为正常组、模型组与扶正化瘀方药物干预组。模型组又分为 2d、1、2、3、4、5、6周共 7个动态观察点。药物组自造模之日起以扶正化瘀方稀释液灌胃 ,共用药 6周。其余大鼠灌以等量生理盐水。天狼猩红染色观察肝组织胶原沉积 ,盐酸水解法测定肝组织羟脯氨酸含量 ,Western印迹法分析肝组织纤维连接蛋白 (FN)、α5 β1与α 平滑肌肌动蛋白 (α SMA )表达量 ,并分析其相关性。结果 随肝纤维化形成 ,模型组大鼠肝组织FN、α5 β1与α SMA蛋白表达量逐渐上升 ,早期以FN升高明显 ,而后以α5 β1及α SMA增加较为显著 ,三者之间呈明显正相关。与模型组比较 ,扶正化瘀方预防组大鼠肝脏胶原沉积减轻 ,肝羟脯氨酸含量下降 ,FN、α5 β1与α SMA蛋白表达减少。 结论 CCl4大鼠肝纤维化形成中肝脏整合素α5 β1表达逐渐增加 ,肝损伤早期FN显著上升 ,并可通过α5 β1促进肝星状细胞活化与肝纤维化。扶正化瘀方抑制肝纤维化大鼠肝脏FN与整合素α5 β1表达 。

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.