阿托伐他汀对LPS诱导的RAW264.7细胞脂代谢相关蛋白及胆固醇流出的影响

The Effect of Atorvastatin on the Expression of Lipid Metabolism Related Proteins and Cholesterol Efflux Induced by Lipopolysaccharide in RAW264.7 Cell

目的研究阿托伐他汀对脂多糖(Lipopolysaccharide,LPS)诱导的小鼠巨噬细胞RAW264.7脂代谢相关蛋白表达及胆固醇流出的影响,并探讨其可能的作用机制。方法用不同浓度LPS刺激RAW264.7细胞,在不同时间点以Western blot方法检测脂质代谢相关蛋白ABCA1、ABCG1、SR-B1、PCSK9和LDLR的表达,从而确定LPS最佳作用浓度和时间。Western blot检测不同浓度阿托伐他汀对50ng/m L LPS诱导的上述脂代谢相关蛋白表达变化的影响,激光共聚焦观察BODIPY荧光标记的胆固醇流出状况。结果在RAW264.7细胞中,LPS呈浓度和时间依赖性抑制ABCA1、ABCG1、SR-B1和LDLR蛋白的表达,对PCSK9蛋白表达无显著影响。阿托伐他汀浓度依赖性的上调LPS诱导的ABCA1、ABCG1、SR-B1和LDLR蛋白表达降低,上调PCSK9蛋白的表达,从而增加胆固醇流出,减少细胞内胆固醇聚集。结论阿托伐他汀干预能够改善LPS引起的脂代谢相关蛋白表达并增强胆固醇流出,该作用可能是其抗动脉粥样硬化机制之一。

Objective To investigate the effect of atorvastatin on the expression of lipid metabolism related protein and cholesterol efflux induced by lipopolysaccharide （LPS） in RAW264.7 cell. Methods RAW264.7 cells were stimulated by LPS at different concentrations and different time, and detected the expression ofABCA1, ABCGI, SR-B1, PCSK9 and LDLR by Western blot in the RAW264.7 cells. The impacts of atorvastatin at different concentrations on the expression of lipid metabolism related proteins induced by LPS 50ng/mL were determined by Westen blot, and the effects on cholesterol efflux were detected by confocal microscopy with BODIPY-cholesterol fluorescent dye. Results LPS downregulated the expression of ABCAI, ABCGI, SR-BI and LDLR in a dose and time dependent manner in RAW264.7 cells significantly, while the expression of PCSK9 protein have no significant difference, Atorvastatin increases the expression of ABCAI, ABCGI, SR-B1 and LDLR protein downregulated by LPS in a dose-dependent manner, enhance the expression of PCSK9 protein and increase cholesterol efflux in RAW264.7 cells. Conclusions Atorvastatin can improve the expression of lipid metabolism related proteins and enhance cholesterol efflux impaired by LPS, which suggesting one of the anti-atherosclerotic mechanisms.