黄芪甲苷对肝纤维化模型大鼠的改善作用机制研究

Study on Mechanism of Improvement Effects of Astragaloside IV on Hepatic Fibrosis Model Rats

关键词:  黄芪甲苷  肝纤维化  上皮间质转化  E-钙黏蛋白  N-钙黏蛋白  α-平滑肌动蛋白  转化生长因子

Key words:  astragaloside IV  hepatic fibrosis  epithelial-mesenchymal transition  E-cadherin  N-cadherin  α-SMA  TGF-β1

摘要:

目的 观察黄芪甲苷对CCl4诱导的肝纤维化模型大鼠的改善作用及可能机制。方法 将SD大鼠随机分为正常组、模型组、水飞蓟宾组(30 mg·kg^–1)、黄芪甲苷组(14 mg·kg^–1)。采用50% CCl4橄榄油溶液(1.5 mL·kg^–1)腹腔注射建立肝纤维化模型,每周2次,持续8周。然后各组大鼠按照每天10 mL·kg^–1灌胃相应药物,共4周。检测大鼠血清中丙氨酸氨基转移酶(ALT)、天门冬氨酸氨基转移酶(AST)含量;计算肝脏指数;苏木素-伊红(HE)及Masson染色观察肝组织病理变化;Western blotting检测转化生长因子(TGF-β1)、上皮间质转化标志物E-钙黏蛋白(E-cadherin)、N-钙黏蛋白(N-cadherin)和α-平滑肌动蛋白(α-SMA)的蛋白表达水平;实时荧光定量PCR检测TGF-β1和E-cadherin的mRNA表达水平。结果 与正常组相比,模型组大鼠肝脏指数显著升高(P<0.01),血清中ALT、AST含量明显上升(P<0.01),胶原容积分数明显增加(P<0.01),肝组织内E-cadherin蛋白表达明显下降(P<0.01),α-SMA、N-cadherin蛋白表达明显升高(P<0.01),TGF-β1 mRNA及蛋白表达水平明显上升(P<0.05或P<0.01)。与模型组比较,黄芪甲苷组肝脏指数大幅下降(P<0.01),血清中ALT和AST含量明显降低(P<0.01),胶原容积分数明显下降(P<0.01),肝组织内E-cadherin蛋白表达上调(P<0.05),α-SMA、N-cadherin蛋白表达显著下调(P<0.01),TGF-β1蛋白和mRNA表达下降(P<0.01或P<0.05)。结论 黄芪甲苷对CCl4诱导肝纤维化模型大鼠具有改善作用,其机制可能与下调N-cadherin、α-SMA、TGF-β1蛋白表达,上调E-cadherin蛋白表达有关。

Abstract:

OBJECTIVE To observe the improvement effect of astragaloside IV on CCl4-induced hepatic fibrosis model rats and its possible mechanism.METHODS SD rats were randomly divided into normal group, model group, silibinin group(30 mg·kg^-1), and astragaloside IV group(14 mg·kg^-1). The hepatic fibrosis model was established by intraperitoneal injection of 50% CCl4 olive oil solution(1.5 mL·kg-1) twice a week for 8 weeks. Then rats in each group were given the corresponding drugs by intragastric administration of 10 mL·kg^-1 per day for 4 weeks. Detected the content of alanine aminotransferase(ALT) and aspartate aminotransferase(AST) in rat serum. Calculated the liver index. Hematoxylin-eosin(HE)and Masson staining were used to observe the pathological changes of liver tissue. Western blotting were used to detect the protein expression level of transforming growth factor(TGF-β1), epithelial-mesenchymal transition(EMT) markers E-cadherin,N-cadherin and α-smooth actin(α-SMA). Real-time PCR were used to detected the mRNA expression levels of TGF-β1 and E-cadherin.RESULTS Compared with the normal group, the liver index of rats in the model group was significantly increased(P<0.01), the contents of ALT and AST in the serum were significantly increased(P<0.01), the collagen volume fraction was significantly increased(P<0.01), and TGF-β1 mRNA in the liver tissue and protein expression levels increased(P<0.05 or P<0.01), E-cadherin protein expression was significantly decreased(P<0.01), α-SMA, N-cadherin protein expression was significantly increased(P<0.01). Compared with the model group, the liver index in the astragaloside IV group significantly decreased(P<0.01), the serum ALT and AST content was significantly decreased(P<0.01), the collagen volume fraction was significantly decreased(P<0.01), and E-cadherin in the liver tissue protein expression was up-regulated(P<0.05), α-SMA,N-cadherin protein expression was significantly down-regulated(P<0.01), TGF-β1 protein and mRNA expression decreased(P<0.01 or P<0.05).CONCLUSION Astragaloside IV has an ameliorating effect on CCl4-induced hepatic fibrosis model rats, and its mechanism may be related to down-regulation of N-cadherin, α-SMA, TGF-β1 protein expression and up-regulation of E-cadherin protein expression.