蒿属香豆素对MCD饮食诱导的非酒精性脂肪性肝纤维化小鼠保护性作用的研究

目的:探讨中药茵陈蒿的主要成分蒿属香豆素对蛋氨酸胆碱缺乏(MCD)诱导的非酒精性脂肪性肝纤维化小鼠的作用及分子机制。方法:采用MCD饲料喂养小鼠6 周进行造模,将50只20 g左右的ICR雄性小鼠随机分为五组:空白对照组,模型组,丹酚酸B组(10 mg/kg),蒿属香豆素低剂量组(30 mg/kg),蒿属香豆素高剂量组(60 mg/kg)。造模后1周灌胃,5周后取小鼠肝脏组织和血清进行实验,对肝脏组织进行病理检查。通过试剂盒检测各组小鼠血清生化指标,比色法测肝脏组织丙二醛(MDA)、超氧化物歧化酶(SOD)含量。Western blot方法测小鼠肝脏组织液α-SMA,Ⅰ型胶原蛋白,E钙黏蛋白,波形蛋白、转化生长因子β₁(TGF-β₁)通路蛋白的表达。结果:不同剂量蒿属香豆素组和丹酚酸B组的NAS评分、MDA水平、α-SMA、Ⅰ型胶原、波形蛋白的表达明显降低,E钙黏蛋白、SOD水平显著增高(P<0.05),TGF-β₁及p-Smad2/3的表达降低,Smad7的表达明显增高(P<0.05)。结论:蒿属香豆素能抑制TGF-β/Smad通路,有效改善肝脏脂质沉积,降低小鼠肝脏组织内氧化应激水平,逆转上皮间质转化,减轻纤维化。

Protective effect of scoparone on MCD diet induced liver fibrosis in mice

Objective:To investigate the influence of scoparone on methionine-choline-deficient(MCD)diet-induced liver fibrosis in mice and the possible mechanism.Methods:Fifty mice weighing 20 g were randomly allocated into five groups:normal group,liver fibrosis group,Salvianolic acid B group(SA-B),low dose(L-Sc)and high dose of scoparone(H-Sc)group.Mice were fed with MCD diet except the normal group.After a week,the mice randomly received saline containing high or low dose scoparone(60 mg/kg,30 mg/kg,respectively)or salvianolic acid B(10 mg/kg)by oral administration.After 5 weeks,liver tissue and serum were obtained for experiments.The liver tissues were pathologically analyzed.Detect biochemical parameters of rat serum by the kits.The levels of MDA and SOD in liver tissues were identified by colorimetric.The expression of α-SMA,collagen Ⅰ,E-cadherin,vimentin,TGF-β₁,Smad2/3,p-Smad2/3 and smad7 were identified by Western blot.Results:Compared with the liver fibrosis group,the level of MDA,the expressions of α-SMA,collagen Ⅰ and vimentin in the experimental groups decreased significantly,while the levels of SOD and the expression of E-cadherin increased(P<0.05).Scoparone or salvianolic acid B treatment resulted in significant down regulation of TGF-β and p-Smad2/3 levels.Furthermore,Smad7 expression increased significantly in all the experimental groups(P<0.05).Conclusion:Scoparone alleviates the lipid deposition induced by MCD diet in liver,prevents or mitigates liver oxidation,fibrosis,and epithelial-to-mesenchymal(EMT)possibly by regulating TGF-β/Smad pathway.