Adipophilin通过PI3K/Akt通路促进细胞内脂质蓄积

Adipophilin promotes intracellular lipid accumulation through PI3K/Akt signaling pathway

目的:探讨adipophilin促进细胞内脂质蓄积的可能机制,为动脉粥样硬化的防治提供参考。方法:分别通过q PCR、Western blot和油红O染色观察氧化型低密度脂蛋白(ox LDL)处理RAW264.7细胞不同时间后,细胞内Akt、p-Akt和adipophilin的蛋白水平及脂质蓄积情况;并检测PI3K/Akt抑制剂LY294002处理后,上述指标的变化;HEK293细胞过表达adipophilin后,检测Akt的活性;并用免疫共沉淀实验检测adipophilin与Akt之间的相互作用。结果:ox LDL处理细胞后,随着时间的延长,脂滴增多,Akt被活化,adipophilin表达增加,而LY294002处理则可抑制上述变化;过表达adipophilin后,p-Akt水平增高,但adipophilin与Akt之间未见直接相互作用。结论:Adipophilin可通过PI3K/Akt途径促进细胞内脂质蓄积,但可能不是通过直接相互关系发挥作用的。

AIM： To observe the possible mechanism through which adipophilin promotes the accumulation of intracellular lipids,and to provide a reference for controlling atherosclerosis. METHODS： RAW264. 7 cells were incubated with oxidized low-density lipoprotein（ ox LDL） for different time. q PCR,Western blot and Oil red O staining were used to observe the mRNA and protein levels of Akt,p-Akt and adipophilin and lipid accumulation. The above indexes were measured after the cells were treated with PI3 K/Akt signaling pathway inhibitor LY294002. The activation of Akt was analyzed in the HEK293 cells over-expressing adipophilin. Co-immunoprecipitation was applied for analysis of protein-protein interaction between adipophilin and Akt. RESULTS： After incubation with ox LDL,the amount of lipid droplets,Akt activity and adipophilin expression increased in the cells with the extension of time（ P〈0. 05）. Moreover,LY294002 inhibited the above changes. The p-Akt levels increased after adipophilin over-expression. No direct interaction between adipophilin and Akt proteins was observed. CONCLUSION： Adipophilin promotes the accumulation of intracellular lipids through PI3 K/Akt signaling pathway,but possibly not by direct interaction between adipophilin and Akt proteins.