SIRT1/UCP2通路在脂肪变性HepG2细胞线粒体能量代谢中的调控机制  

Regulatory mechanism of SIRT1 / UCP2 pathway in mitochondrial energy metabolism of steatotic HepG2 cells

作　　者：张玉佩[1] 孔怡琳[2] 杨钦河[1] 邓远军[1] 梁荫基[1] 金玲[3] 何毅芳 李媛媛[1] 王观龙[1] 程少冰[1] 

机构地区：[1]暨南大学医学院,广东广州510632 [2]广东省中医院大学城医院 [3]暨南大学附属第一医院

出　　处：《中国老年学杂志》2016年第3期513-516,共4页Chinese Journal of Gerontology

基　　金：国家自然科学基金资助项目(No.81302878;81273617);中国肝炎防治基金会天晴肝病研究基金(No.cfhpc20132184);暨南大学第一临床医学院科研培育专项基金(No.2014205);广东省中医药局项目(No.20151224);广东省医学科研基金项目(No.A2015521)

摘　　要：目的采用油酸诱导Hep G2细胞发生脂变,建立脂肪变性细胞模型,观察SIRT1/UCP2通路在脂肪变性Hep G2细胞能量代谢中的调控机制。方法采用含有2 mmol/L油酸的DMEM培养基诱导Hep G2细胞24 h后,建立脂肪变性Hep G2细胞模型,并设置对照组比较。以油红O染色观察细胞内脂滴形成状况,并用全自动生化仪检测细胞上清丙氨酸氨基转移酶(ALT)、天门冬氨酸氨基转移酶(AST)含量和细胞内甘油三酯(TG)含量;采用流式细胞仪测定线粒体膜电位的改变,采用磷钼酸比色试剂盒测定细胞内三磷酸腺苷(ATP)含量,运用Western印迹法检测各组细胞SIRT1和UCP2蛋白的表达。结果与对照组比较,模型组细胞内橘红色脂滴大量形成,且TG含量明显升高(P<0.01),线粒体膜电位及细胞内ATP含量显著降低(P<0.05,P<0.01),SIRT1蛋白表达均显著降低(P<0.05),UCP2蛋白表达显著升高(P<0.01)。结论油酸诱导的脂肪变性Hep G2细胞模型可以出现脂质代谢紊乱和线粒体能量代谢失衡,其机制可能与细胞内SIRT1/UCP2通路的激活有关。Objective To establish a steatotic HepG2 cell model induced by oleic acid, and observe the regulatory mechanism of SIRT1/UCP2 pathway in energy metabolism of steatotic HepG2 cells. Methods Induced by DMEM medium of 2 mmol/L oleic acid for 24 hours, the steatotic HepG2 cell model was successfully established. Then, lipid droplets in cytoplasm were observed by oil red O staining, while alanine aminotransferase （ALT）, aspartate aminotransferase （AST） in ~rnm, and triglyceride （TG） accumulation in HepG2 cells were measured by automatic biochemical analyzer. The changes of mitochondrial membrane potential were determined by flow cytometry, and intracellular adenosine triphosphate（ATP） level was detected by biological reagent kit. The protein expressions of SIRTI and UCP2 were analyzed by Western blot. Results Compared with those of control group, the level of TG accumulation was significantly highet（P〈 0.01 ）, and 10ts of red lipid droplets inside cytoplasm were visible, while mitochondrial membrane potential and intracellular ATP levels were significantly reduced（ P〈0.05 ,P〈0.01 ） in model group. The expression of SIRT1 protein was significantly lower（ P〈0.05 ） , where- as the expression of UCP2 protein was significantly higher（ P〈0.01 ） in model group. Conclusions The oleic acid-induced steatosis in HepG2 cells might result in lipid metabolism disorder and mitochondrial dysfunction, possibly by activating the SIRT1/UCP2 pathway in HepG2 cells.

关 键 词：HEPG2细胞 脂肪变性 SIRT1/UCP2通路 能量代谢 

分 类 号：Q493.5[生物学—生理学]