雌激素抑制脂滴包被蛋白Perilipin 2减少肝细胞脂质沉积

Estrogen reduces lipid deposition in liver cells by inhibiting Perilipin 2

目的:研究雌激素减少导致肝细胞脂质沉积的可能机制,为围绝经期女性非酒精性脂肪肝的研究奠定实验基础。方法:采用油酸诱导建立肝细胞脂肪变性模型,设置DMSO对照组、油酸模型组、油酸+雌激素实验组,尼罗红染色法鉴定肝细胞内脂质沉积情况。免疫荧光染色和蛋白免疫印记实验检测脂滴包被蛋白Perilipin2(Plin2)的表达变化。结果:成功建立油酸诱导肝细胞脂肪变性模型,尼罗红染色可见高亮橘红色的脂滴形成。雌激素剂量依赖性的减少油酸诱导的肝细胞内脂质沉积。免疫荧光染色显示雌激素能够明显抑制油酸诱导的Plin2的表达,荧光信号降低。蛋白免疫印迹实验证实雌激素能够减少Plin2的蛋白表达水平,DMSO对照组、油酸诱导模型组和雌激素实验组Plin2蛋白表达相对光密度分别为0.409±0.051、0.739±0.060、0.438±0.061,雌激素显著性减少了油酸诱导的Plin2的蛋白表达水平(P<0.05)。结论:雌激素能够减少肝细胞内的脂质沉积,可能是通过抑制脂滴包被蛋白Plin2而实现。

Objective： To investigate the possible mechanism of estrogen reducing lipid deposition in liver cells. Methods： The hepatocyte steatosis model was induced by oleic acid. DMSO control group,oleic acid group,oleic acid plus estrogen group were set up. The expression level of Perilipin2（ Plin2） was detected by immunofluorescence staining and western blotting. Results： The hepatocyte steatosis model was successfully established. Nile red staining showed lipid droplet formation in hepatocytes. Estrogen could does dependently reduce lipid deposition in hepatocytes induced by oleic acid. Immunofluorescence staining showed that estrogen could inhibit the expression of Plin2 induced by oleic acid. Western blotting showed that estrogen could reduce the protein expression level of Plin2 induced by oleic acid significantly（ P〈 0. 05）. Relative light density of Plin2 protein expression in DMSO group,oleic acid group and estrogen group was 0. 409 ± 0. 051,0. 739 ±0. 060 and 0. 438 ± 0. 061 respectively. Conclusion： Estrogen can reduce lipid deposition in liver cells,probably by inhibiting the expression of Plin2.