五羟黄酮调节肝癌HepG2细胞bax基因表达诱导细胞凋亡的实验研究

目的:探讨三磷酸肌醇( IP3) 和bax基因表达变化在五羟黄酮(Quercetin)诱导肝癌细胞凋亡中的作用。方法:以肝癌HepG2 细胞培养72 h为对照,以20，40，60，80μmol/L Quercetin作用于 HepG2 细胞72 h 时和60μmol/L Quercetin 作用于 HepG2 细胞 6，12，24，48，72 h，应用同位素试剂盒检测细胞IP3含量,RT-PCR分析bax mRNA表达，Western blotting 分析细胞bax蛋白表达,流式细胞仪检测细胞凋亡率。结果:各浓度的Quercetin作用于肝癌HepG2 细胞72 h，IP3含量显著低于对照组(P<0.01)，bax mRNA和bax蛋白表达显著高于对照组，细胞凋亡率显著高于对照组(P<0.01); 60 μmol/L Quercetin 作用于肝癌HepG2 细胞6，12，24，48，72 h,各时相IP3含量显著低于对照组(P<0.01）;12 h后bax mRNA和bax蛋白表达显著高于对照组，24 h后各时相细胞凋亡率为显著高于对照组（P<0.01）。结论:Quercetin能减少IP3生成,上调bax基因表达,诱导肝癌细胞凋亡。

Quercetin regulates bax gene expression and induces apoptosis in hepatocellular carcinoma HepG2 cells

Abstract:Objective:To explore the role of 1, 4, 5-trisphosphate inositol ( IP3) and bax gene expression in apoptosis of HepG2 cells induced by Quercetin.Methods :HepG2 cells were cultured for 72h as control. HepG2 cells were treated with different concentrations including 20,40.60,80μmol/L Quercetin for 72h, and treated with 60μmol/ L Quercetin for 12h, 24h, 48h and 72h. IP3, bax mRNA, bax protein and apoptosis rate were assayed by IP3-［3H］ Birtrak assay,RT-PCR, Western blotting and flow cytometry, respectively.Results:In HepG2 cells incubated with each of the concentrations of Quercetin for 72 h，IP3continent was lower than that of control(P<0.01)，bax mRNA expression and bax protein expression was higher than that of control，and the apoptosis rate was higher than that of control; in HepG2 cells incubated with Quercetin for 6 h, 12 h, 24 h, 48 h, 72 h, IP3content was lower than that of control(P<0.01);bax mRNA and bax protein expression in groups incubated with 60 μmol/L Quercetin for 12h was higher than that of control， and the apoptosis rate in groups incubated with 60μmol/ L Quercetin for 24h, 48h and 72h was significantly higher than that in control (P<0.01).Conclusions:Quercetin induces apoptosis of HepG2 cells by reducing IP3production and up-regulating bax gene expression.