SCAP在培养肝细胞脂肪变性模型中的表达及意义

Expression and role of SCAP in models of cultured steatosis hepatocytes

目的探讨油酸诱导的脂肪变性肝细胞模型固醇调节元件结合蛋白裂解激活蛋白(srebp cleavage activating protein,SCAP)的表达及意义。方法以正常肝细胞株L-02进行细胞培养,用油酸诱导建立肝细胞脂肪变性模型。采用油红O染色观察细胞内的脂滴,并检测细胞内甘油三酯含量,RT-PCR法检测SCAP mRNA的表达,Weston blot检测SCAP蛋白的表达。结果油红O染色显示24h开始出现脂肪变性,120h脂肪变性最重;模型组肝细胞内甘油三酯(TG)含量在各时相点较对照组显著升高,差异有统计学意义(P<0.01),120h增高最明显;模型组SCAP mRNA的表达上调,于24h开始增高,72h表达最强,与对照组相比差异有统计学意义(P<0.01);SCAP蛋白的表达24h开始增高,120h最强,与对照组相比差异有统计学意义(P<0.01)。结论油酸诱导的脂肪变性肝细胞模型SCAP的表达增强,细胞内TG的合成增加,SCAP可能参与了肝细胞的脂代谢及脂肪变性的形成。

Objective To explore the expression and role of SCAP in the models of cultured steatosis hepatocytes. Methods Steatosis models of hepatocytes was established by adding oleic acid to the growing L-02 cell strain. The expression of SCAP mRNA was measured with RT-PCR and the protein expression of SCAP were measured by Western blot, lipid droplets in the hepatocytes were observed with oil red staining and the contents of triglyceride in hepatocytes were measured with analyzed kit. Results In model groups,mRNA expression of SCAP increased at 24h,and elevated remarkably at 72h compared with the normal control group（P〈0.01）, and protein expression of SCAP increased at 24h,and elevated remarkably at 120h compared with the control group（P〈0.01）. Triglyceride contents in hepatocytes of these groups also increased. Through oil red staining, a few lipid droplets were observed at 24h and steatosis hepatocyte increased greatly at 120h. Conclusion The overexpression of SCAP in model groups could lead to disturbance of lipid metabolism and probably SCAP participates the process of steatosis of hepatocytes.