SMAD4低表达促进人血管平滑肌细胞迁移和凋亡

SMAD4 gene silencing promotes human vascular smooth muscle cells migration and apoptosis

目的:观察SMAD4表达下调对人主动脉血管平滑肌细胞(human aortic smooth muscle cell,HASMC)迁移及凋亡的影响。方法:以siRNA-SMAD4转染HASMC,抑制SMAD4表达,以细胞迁移实验(Transwell)和流式细胞术检测平滑肌细胞的迁移和凋亡率;蛋白质印迹法检测各凋亡相关蛋白的表达。结果:与阴性对照组相比,转染siRNA-SMAD4后HASMCs早期和晚期细胞凋亡率均明显升高(P均<0.05)。Transwell实验结果显示,siRNASMAD4组平均每视野迁移细胞数为114±21,明显多于空白组和阴性对照组(分别为19±6,25±7,P均<0.01)。蛋白质印迹结果显示SMAD4低表达引起Cleaved Caspase-3表达上调、Bal-2表达下调。结论:SMAD4低表达明显促进HASMC迁移和凋亡,有可能与主动脉瘤发生发展的病理机制相关。

Objective： To observe the effect of SMAD4 gene-silence on migration and apoptosis of human vascular smooth muscle cells（HASMC）. Methods： HASMC was transfected with siRNA to inhibit the expression of SMAD4 gene. The migration and apoptosis of HASMC were detected by Transwell assay and flow cytometry. Western blotting assay was used to detect the effects of SMAD4 expression on apoptosis related protein factors. Results： Compared with the negative control（NC） group, the apoptosis rate of HASMC increased significantly after siRNA-SMAD4 transfection（P〈0. 05）. In Transwell assay, the average numbers of migration cells per field in the blank group,NC group and siRNA-SMAD4 group were 19 ±6,25 ±7 and 114 ± 21 respectively. Compared with the blank group and NC group,there was a significant increase in the number of HASMC migration cells after transfection of siRNA-SMAD4（P〈0. 01）. Western blotting experiment showed that the SMAD4 gene-silence caused cleaved caspase-3 upregulation.Conclusion ： SMAD4 gene-silence significantly promotes the migration and apoptosis of HASMC,indicating that SMAD4 be related to the pathogenesis of aortic aneurysm.