二甲双胍对人肝细胞Huh7脂质蓄积的影响及作用机制

Effect and mechanism of metformin on lipid accumulation in Huh7 hepatocytes

目的研究二甲双胍对肝细胞脂质蓄积的影响及作用机制。方法体外培养人源Huh7肝细胞,细胞随机分为空白对照组及5 mmol/L二甲双胍、10 mmol/L二甲双胍、15 mmol/L二甲双胍处理组,确定最佳浓度后,使用LDL荷脂,然后分为空白对照组、LDL处理组和LDL+15 mmol/L二甲双胍处理组。实验终点,采用细胞增殖及毒性检测试剂盒检测细胞存活率,油红O染色和BODIPY脂质探针检测细胞内脂质含量,Dil-LDL检测细胞脂质摄取能力,Western blot分析固醇调节元件结合蛋白2(SREBP-2)、SREBP-1c、低密度脂蛋白受体(LDLR)和前蛋白转化酶枯草溶菌素9(PCSK9)蛋白的表达情况。结果二甲双胍可抑制LDL诱导的肝细胞脂质蓄积,降低SREBP-2、SREBP-1c、LDLR和PCSK9的蛋白表达。结论二甲双胍可能通过减少转录因子SREBP-2和SREBP-1c,下调LDLR表达,从而抑制细胞脂质蓄积。

Aim To investigate the effect and mechanism of metformin on lipid accumulation in Huh7 hepatocytes.Methods Huh7 cells were cultured in vitro and divided into:blank control group,5 mmol/L,10 mmol/L and 15 mmol/L metformin treatment group.After determing the optimal concentration,LDL was used to load fat,and then divided into:blank control group,LDL group,LDL+15 mmol/L metformin treatment group.Cell proliferation and toxicity test kits were used to detect cell survival rate,oil red O and BODIPY lipid probes were used to detect intracellular lipid content,Dil-LDL was used to detect cell lipid uptake capacity,and Western blot analysis was performed on sterol regulatory element binding protein-2(SREBP-2),sterol regulatory element binding protein-1c(SREBP-1c),low density lipoprotein receptor(LDLR)and proprotein convertase subtilisin/kexin 9(PCSK9)protein expression.Results Metformin can inhibit LDL-induced lipid accumulation in Huh7 hepatocytes and reduce protein expression of SREBP-2,SREBP-1c,LDLR,and PCSK9.Conclusion Metformin reduces intracellular lipid uptake by reducing LDLR expression and inhibiting the expression of the transcription factors SREBP-2 and SREBP-1c.