Akt/mTOR信号在转化生长因子-β诱导动脉内皮间质转化中的作用研究  

The role of Akt/mTOR signal in TGF-β-induced arterial endothelial-mesenchymal transition

作　　者：毕华强[1] 刘辉[1] 张曦[1] 马宽生[1] 张辉[2] 

机构地区：[1]第三军医大学附属西南医院肝胆外科,重庆400038 [2]第三军医大学附属西南医院放射科介入病房,重庆400038

出　　处：《中国普外基础与临床杂志》2017年第7期808-812,共5页Chinese Journal of Bases and Clinics In General Surgery

摘　　要：目的探讨转化生长因子(TGF)-β诱导动脉内皮细胞间质转化的分子信号机制。方法采用外植贴壁法分离培养原代大鼠动脉内皮细胞,继而用重组TGF-β(10 ng/m L)孵育48 h,采用免疫细胞染色观察内皮细胞标志物表达的变化,同时采用免疫蛋白印迹法检测内皮细胞Akt/mTOR信号的活化情况。并分别以Akt抑制剂及mTOR抑制剂预处理内皮细胞,观察Akt/mTOR信号抑制后,TGF-β诱导内皮细胞标志物表达的变化情况。结果大鼠动脉内皮细胞经TGF-β孵育后,其平滑肌细胞标志物平滑肌肌动蛋白(α-smooth muscle actin,α-SMA)和平滑肌(smooth muscle,SM)-22α表达明显上调,而内皮细胞标志物CD31和v W因子的表达明显下调;同时,TGF-β孵育后内皮细胞磷酸化Akt和磷酸化mTOR的表达也明显上调。在应用Ly294002(20μmol/L)及雷帕霉素(rapamycin,10 nmol/L)分别抑制Akt及mTOR磷酸化活化后,TGF-β诱导的内皮细胞上述标志物的表达则明显下调。结论 TGF-β通过磷酸化活化Akt/mTOR信号诱导动脉内皮细胞向间质平滑肌细胞分化,提示其可能是移植动脉硬化内膜增生的机制之一。Objective To investigate the molecular signal mechanism of transform growth factor （TGF）-β induced arterial endothelial-mesenchymal transition. Methods Rat arterial endothelial cells were primarily cultured by ex-transplant method. The endothelial cells were incubated by combinant TGF-β （10 ng/mL） for 48 hours and then were detected by immunofluorescence staining and western blotting to observe the cell surface marker expression profile and Akt/mTOR signal activation. On the other hand, the endothelial cells were preincubated by Ly294002 （20 μmol/L） and rapamycin （10 nmol/L） to inhibit the Akt/mTOR signal, and then the cells were further treated with TGF-β （10 ng/mL） for 48 hours to observe the cell surface marker expression profile without Akt/mTOR signal activation. Results Rat artery endothelial cells by TGF-β after incubation, the expressions of smooth muscle cell markers α-smooth muscle actin （α-SMA） and smooth muscle-22α （SM-22α） were up-regulated, and the endothelial cell markers CD31 and vW factor were significantly down-regulated, at the same time, the expressions of phosphorylated Akt and mTOR were also up-regulated. However, after preincubation of Ly294002 （20 μmol/L） and rapamycin （10 nmol/L） to inhibit the phosphorylation of Akt and mTOR signal, above TGF-β-induced expressions of α-SMA and SM-22α in arterial endothelial cells were significantly suppressed and the expressions of CD31 and vWF were preserved. Conclusion TGF-β-induced arterial endothelial-mesenchymal transition is dependent on activation of Akt/mTOR signal, suggesting that Akt/mTOR-dependent arterial endothelial-mesenchymal transition would be one of the mechanisms for intima hyperplasia in transplant arteriosclerosis.

关 键 词：转化生长因子-Β 动脉内皮细胞 平滑肌细胞 信号通路 

分 类 号：R617[医药卫生—外科学]