熊果酸对肝细胞胆固醇代谢的影响

摘要

目的 探讨熊果酸对人肝癌细胞HepG2及小鼠肝细胞AML-12胆固醇代谢的影响及其相关机制.方法 0,10,20,40μmol·L-1熊果酸处理HepG2及AML-12细胞24 h,应用反转录-聚合酶链反应(RT-PCR)、Western blotting检测细胞内胆固醇代谢关键基因胆固醇7A-羟化酶(CYP7A1)mRNA和蛋白表达,应用酶法检测细胞内胆固醇浓度.结果 与0μmol·L-1熊果酸组比较,20和40μmol·L-1熊果酸组HepG2及AML-12细胞内CYP7A1 mRNA及蛋白表达水平均显著增加(均P<0.05),相应的细胞内胆固醇浓度也随之下降(均P<0.05).结论 一定浓度的熊果酸能够降低肝细胞内胆固醇浓度,CYP7A1可能参与了调节过程.%Objective To explore the effects and mechanism of ursolic acid ( UA) on cholesterol metabolism in human hepatocellular carcinoma HepG2 and mouse hepatocyte AML-12. Methods HepG2 and AML-12 cells were treated with different concentrations of UA (0,10,20,40 μmol·L-1)for 24 h, then the mRNA and protein expression of cholesterol 7alpha-hydroxylase (CYP7A1) and intracellular cholesterol level was detected by RT-PCR、Western blotting and enzymatic method, respectively. Results Compared with 0 μmol·L-1 UA, 20 μmol·L-1 and 40 μmol·L-1 UA significantly increased the expressions of CYP7A1 mRNA and protein(P<0. 05), and decreased intracellular cholesterol level in HepG2 and AML-12 cells (P<0. 05). Conclusion A certain concentration of UA can reduce the level of cholesterol in HepG2 and AML-12 cells. CYP7A1 may be involved in the regulation process.