白藜芦醇对肝癌HepG_2细胞中脂肪合成的抑制作用及其机制

Inhibitory effect of resveratrol on fat synthesis in liver cancer HepG_2 cells and its mechanism

目的:探讨白藜芦醇(Res)对肝癌HepG_2细胞脂肪合成的影响,阐明其可能机制。方法:体外培养HepG_2细胞,分为Res组(40μmol·L^(-1) DMSO稀释的Res作用24h)和对照组(相同浓度的DMSO作用24h)。收集细胞上清,ELISA法检测2组细胞中甘油三酯(TG)和总胆固醇(TC)水平。采用实时荧光定量PCR (qRT-PCR)和Western blotting法分别检测2组细胞中脂肪合成酶乙酰辅酶A羧化酶(ACC1)、脂肪酸合成酶(FASN)、硬脂酰辅酶A去饱和酶(SCD1)mRNA和蛋白表达水平,采用Western blotting法检测2组细胞中氧链接N乙酰葡糖胺(O-GlcNAc)糖基化水平。结果:与对照组比较,Res组细胞中TG和TC水平均下降,但差异无统计学意义(t1=1.886,P<0.05;t_2=2.457,P>0.05);与对照组比较,Res组细胞中ACC1、FASN、SCD1mRNA和蛋白表达水平均明显降低(P<0.05或P<0.01),O-GlcNAc糖基化水平明显降低(t=2.87,P<0.05)。结论:Res具有抑制肝癌HepG_2细胞脂肪合成的作用,其机制可能与降低细胞中O-GlcNAc糖基化水平和FASN表达有关。

Objective:To investigate the effect of resveratrol(Res)on the fat synthesis in the liver cancer HepG 2 cells,and to elucidate its possible mechanism.Methods:The HepG 2 cells were cultured in vitro and divided into Res group(treated with 40μmol·L^-1 DMSO-diluted Res for 24 h)and control group(treated with the same concentration of DMSO for 24 h).The cell supernatant was collected,and the levels of triglyceride(TG)and total cholesterol(TC)in the cells in various groups were measured by ELISA.The mRNA and protein expression levels of lipase synthase acetyl-CoA carboxylase(ACC1),fatty acid synthetase(FASN)and stearoyl-CoA desaturase(SCD1)in the cells in various groups were detected by qRT-PCR and Western blotting method.The levels of O-linked N-acetylglucosamine(O-GlcNAc)glycosylation in the cells in various groups were detected by Western blotting method.Results:Compared with control group,the levels of TG and TC in the cells in Res group were decreased,but the difference was not statistically significant(t 1=1.886,P>0.05;t 2=2.457,P>0.05).Compared with control group,the levels of expressions of ACC1,FASN and SCD1 mRNA and proteins in the cells in Res group were significantly decreased(P<0.05 or P<0.01);the O-GlcNAc glycosylation level in the cells in Res group was significantly decreased(t=2.87,P<0.05).Conclusion:Res has the effect of inhibiting the fat synthesis in the liver cancer HepG 2 cells.Its mechanism may be related to the reduction of cellular O-GlcNAc glycosylation level and the reduction of the expression of FASN.