茶条槭总黄酮提取物抗小鼠肝纤维化作用及其机制研究

目的研究茶条槭总黄酮提取物(AF)对四氯化碳(CCl 4)致小鼠肝纤维化的保护作用及其作用机制。方法将60只小鼠随机分为模型组、空白对照组、茶条槭总黄酮提取物(AF)高、中、低剂量组(给药剂量分别为400,200和100 mg·kg^-1)和秋水仙碱组(4 mg·kg^-1)。除空白对照组外,其余5组用0.4 g·mL^-1的CCl 4腹壁皮下注射复制小鼠肝纤维化模型,用HE及Masson染色观察肝组织病理变化,用生化试剂盒检测血清谷草转氨酶(AST)、谷丙转氨酶(ALT)和层黏连蛋白(LN)的含量以及Ⅳ型胶原(Col-Ⅳ)的表达水平;用Elisa法检测血清白细胞介素-8(IL-8)和白细胞介素-6(IL-6)的表达水平;用免疫组化染色检测小鼠肝脏α-肌动蛋白(α-SMA)的表达水平;用Real-time PCR检测肝组织转化生长因子-β1(TGF-β1)和信号转导分子-2(SMAD2)mRNA的表达情况;用Western blot技术检测肝组织TGF-β1和SMAD-2的蛋白表达水平。结果与模型组比较,AF高、中剂量组血清ALT、AST、LN含量及Col-Ⅳ、IL-8和IL-6水平均明显降低(P<0.05),肝组织α-SMA表达水平显著下降,CCl 4引起的小鼠肝损伤及纤维化程度明显减轻,肝组织TGF-β1、SMAD2 mRNA及蛋白表达水平显著降低,差异有统计学意义(P<0.05)。结论AF可减轻实验性小鼠肝损伤并改善肝纤维化程度,其作用机制可能与抑制TGF-β1/SMAD通路的激活有密切关系。

Study on the effects of total flavonoids extracted from Acer ginnala Maxim on hepatic fibrosis in mice and its mechanism

Objective To study the protective effect of total flavonoids extract of Acer ginnala Maxim(AF)on hepatic fibrosis induced by carbon tetrachloride(CCl 4)in mice and its mechanism.Methods 60 mice were randomly divided into model group,blank control group,AF high,middle and low doses groups(doses were 400,200 and 100 mg·kg^-1 respectively),and colchicine treatment group(4 mg·kg^-1).Except for blank control group,all mice was injected subcutaneously with 0.4 g·mL^-1 CCl 4 to duplicate liver fibrosis model.HE and Masson staining were used to observe the pathological changes of liver tissue.The levels of serum glutamic oxaloacetic transaminase(AST),alanine aminotransferase(ALT),laminin(LN)and collagen typeⅣ(Col-Ⅳ)were detected by biochemical kit.The levels of serum interleukin-8(IL-8)and interleukin-6(IL-6)were detected by Elisa and the expression of hepaticα-actin(α-SMA)was detected by immunohistochemical staining.Transforming growth factor-β1(TGF-β1)and signal transduction molecule-2(SMAD2)in liver tissue were detected by Real-time PCR.The expression of mRNA and Western blot technique were used to detect the expression level of TGF-β1 and SMAD2 protein in liver tissue.Results Compared with the model group,the levels of ALT,AST,LN,Col-Ⅳ,IL-8 and IL-6 in serum of high and middle dose AF group were significantly decreased(P<0.05),the expression level ofα-SMA in liver tissue was significantly decreased,the degree of liver injury and fibrosis induced by CCl 4 in mice were significantly reduced,and the expression levels of TGF-β1,SMAD2 mRNA and protein in liver tissue were significantly decreased.There was statistical significance(P<0.05).Conclusion Total flavonoids extract of AF can alleviate liver injury and improve liver fibrosis in experimental mice.The mechanism may be related to the inhibition of TGF-β1/SMAD pathway activation.