摘要
目的观察Exendin-4对游离脂肪酸诱导的肝细胞sirt6表达的影响及其在肝脏糖异生过程中的调控作用。方法体外培养人肝癌细胞株Hep G2细胞,根据干预措施分为正常对照组、Exendin-4(100nmol/L)处理组、游离脂肪酸对待组、游离脂肪酸+Exendin-4处理组。Western blot法检测各组细胞中sirt6表达的变化。以stealth siRNA干扰Hep G2细胞中sirt6的表达后给予相同处理,Western blot法检测sirt6表达蛋白水平的变化,RT-PCR检测sirt6及糖异生相关基因G6Pase和PEPCK mRNA水平的变化。结果与正常对照组相比游离脂肪酸可显著降低肝细胞内sirt6蛋白的表达,而经Exendin-4处理后,sirt6表达显著升高。与正常对照组相比,游离脂肪酸可诱导肝细胞糖异生相关基因表达的升高,经过Exendin-4处理后,可相应降低上述基因的表达。当下调sirt6表达后,则抑制了由Exendin-4对改善游离脂肪酸诱导肝细胞糖异生相关基因的调节作用。结论游离脂肪酸可降低肝细胞sirt6的表达,Exendin-4可改善由游离脂肪酸诱导的肝细胞sirt6表达的下降及糖异生相关基因表达的升高;Exendin-4可能是通过对sirt6的调节从而在肝脏糖异生过程中发挥重要作用的。
Objective To examine the influence of Exendin -4 on the experssion of sift6 and other related gluconeogenesis genes in fatty liver cell culture model. Methods HepG2 ceils were randomly divided into 4 groups ： normal control group, Exendin - 4 （ lOOnmol/ L） treated group, FFA treated group, FFA ± Exendin -4 （lOOnmol/L） treated group. Western blot was used to detect the expression of sift6. Stealth siRNA was used to inhibit the expression of sirt6. After the treatment,the mRNA of Sirt6 and hepatic gluconeogenesis gene G6Pase,PEPCK were detected by RT - PCR. Results Compared with the control group,the sirt6 protein expression level was decreased in FFA - stimulated HepG2 cells. However, 100nmol/L Exendin - 4 treatment could improve the FFA - decreased the expression of sirt6. Exendin -4 treatment significantly reduced the mRNA level of G6Pase and PEPCK induced by the FFAs. However, when down -regula- ted the expression of sirt6 by siRNA, the effects of Exendin - 4 on the hepatic gluconeogenic improvement had been diminished. Conclu- sion FFAs could decrease the expression of sirt6 in HepG2 ceils. Exendin - 4 reverse the down - regulation of sirt6 induced by the FFAs. Exendin -4 treatment may attenuate and improve hepatic gluconeogenesis in liver tissues through the activation of sirt6 signaling cascade.
出处
《医学研究杂志》
2015年第1期39-43,共5页
Journal of Medical Research
基金
国家自然科学基金资助项目(81370956)
上海交通大学专项基金资助项目(2011JDZX021)
