摘要
目的探讨磷脂酰肌醇3激酶(PI3K)和哺乳动物雷帕霉素靶蛋白(mTOR)信号通路在柯萨奇病毒B3(CVB3)诱导细胞凋亡中的作用。方法体外培养的HeLa细胞通过CVB3感染建立病毒性心肌炎模型,根据细胞毒力实验筛选10 nmol/L的雷帕霉素(Rapamycin)和25μmol/L的PI3K抑制剂(LY294002)干预CVB3感染的HeLa细胞,采用RT-PCR和Western blot免疫印迹法检测Bim和Bax的mRNA及蛋白质表达。结果感染CVB3 12和24 h后,LY294002和Rapamycin促进CVB3诱导的HeLa细胞产生CPE。与Sham组比较,CVB3可以诱导Bim mRNA和蛋白的表达降低(P<0.05),Bax mRNA表达早期降低而蛋白表达逐渐增强,而与对照组比较,LY294002和Rapamycin可以使Bim mRNA和蛋白的表达增强(P<0.05);LY294002使Bax mRNA表达逐渐减弱而蛋白表达逐渐增强,Rapamycin则使Bax蛋白表达随感染时间延长呈3 h增强(P<0.05),6和12h减弱,24 h增强的动态改变(P<0.05)。结论 PI3K和mTOR信号通路可能通过调控Bim和Bax的表达,在CVB3感染诱导的VMC中扮演重要角色。
Objective To observe the effect of the inhibitor of mTOR （ mammalian target of rapamycin） Rapamycin and the inhibitor of PI3K （phosphatidylinositol kinase 3-kinase） LY294002 on Bim and Bax-members of pro-apop- tosis factors in BCL-2 family in CVB3 induced HeLa cells, and the roles of PI3K and mTOR signaling pathway playing in the CVB3 induced apoptosis. Methods HeLa cells infected by CVB3 were treated with 10 nmoL/L Ra- pamycin and 25μmol/L LY294002 according to the cell toxicity test. The Bim and Bax expressions were deter- mined by both RT-PCR and Western blot. Results Compared with controls （ CVB3 ＋ DMSO）, CPE （ cytopathic effect） at 3 h and 6 h p. i. （postinfection） was not significantly different with which at 12 h and 24 h p. i. , howev- er, CPE in LY294002 and Rapamycin group were more obvious. Compared with Sham, the mRNA and protein expression of Bim decreased induced by CVB3 which blocked by LY294002 and Rapamyein as compared with controls. The mRNA expression of Bax decreased early after CVB3 infection while protein expression increased gradu- ally, which was dynamically affected by LY294002 and Rapamycin. Conclusions LY294002 and Rapamycin pro- mote HeLa ceils apoptosis and expression of both Bim and Bax with the infection time, which illustrates that PI3K and mTOR signaling pathway may play important roles in CVB3 induced VMC by regulating the Bim and Bax ex- pressions.
出处
《基础医学与临床》
CSCD
北大核心
2013年第10期1252-1258,共7页
Basic and Clinical Medicine
基金
国家自然科学基金(0973233)
中南大学2012年研究生自主创新课题(2012zzts035)
