目的研究过氧化物酶体增殖物激活受体α(PPARα)、载脂蛋白A5(ApoA5)在脂联素调控HepG2细胞内甘油三酯(TG)代谢中的作用,并初步探讨脂联素影响TG代谢的机制。方法采用以含10%胎牛血清DMEM培养的HepG2细胞,分为对照组、溶剂组(加入0.1%DMSO)、MK886组(5.0μmol/L MK886+0.1%DMSO)、脂联素组(25μg/ml脂联素+0.1%DMSO)、脂联素+MK886组(25μg/ml脂联素+5.0μmol/L MK886+0.1%DMSO),24h后检测各组细胞内PPARα、ApoA5 mRNA和蛋白的表达水平及TG含量。结果与对照组、溶剂组、脂联素+MK886组比较,MK886组HepG2细胞中PPARα、ApoA5 mRNA及蛋白表达明显降低(P〈0.01),TG含量明显升高(P〈0.01),而脂联素组PPARα、ApoA5 mRNA及蛋白表达明显升高(P〈0.01),TG含量明显降低(P〈0.05)。对照组、溶剂组、脂联素+MK886组3组间比较,PPARα、ApoA5 mRNA和蛋白表达水平及TG含量差异均无统计学意义(P〉0.05)。结论 HepG2细胞中TG的代谢与PPARα、ApoA5密切相关。脂联素可能是通过促进PPARα及ApoA5的表达从而下调HepG2细胞内TG含量。
Objective To investigate the role of PPARα and ApoA5 in regulation of triglyceride(TG) metabolism in HepG2 cell by adiponectin and explore the mechanism responsible for adiponectin in influencing TG metabolism.Methods HepG2 cells were divided into five groups: control group,solvent group,MK886 group,adiponectin group and adiponectin + MK886 group.We detected mRNA and protein expressions of PPARα,ApoA5 and TG levels in each group.Results(1) Compared with control group,solvent group and adiponectin group,the mRNA and protein expressions of PPARα,ApoA5 and TG levels showed more significant decrease(P〈0.05),while TG level significantly increased in HepG2 cells of MK886 group(P〈0.05).(2) The mRNA and protein expressions of PPARα and ApoA5 significantly increased(P0.01) and TG level significantly decreased in adiponectin group.There were no statistically significant difference of mRNA and protein expressions of PPARα,and also ApoA5 and TG levels between control group,solvent group and adiponectin group.Conclusions TG metabolism correlates with PPARα and ApoA5 in HepG2 cells.Adiponectin may decrease TG level in HepG2 cells by enhancing the expressions of PPARα and ApoA5.