微小RNA-211 在颅内动脉瘤中差异表达及其对血管平滑肌细胞凋亡影响

Differential expression of microRNA-211 in intracranial aneurysms and its effect on vascular smooth muscle cell apoptosis

目的探讨微小RNA-211(miR-211)在颅内动脉瘤中的表达变化及其对血管平滑肌细胞凋亡的影响。方法选取2017年5月至2019年1月成都医学院第一附属医院手术切除的颅内动脉瘤组织50例,同时选取同期该院颅脑外伤病人正常颅内动脉血管组织20例。实时荧光定量逆转录聚合酶链反应(qRT-PCR)方法测定颅内动脉瘤中miR-211、B细胞淋巴瘤-2相关X蛋白(Bax)表达变化。在动脉瘤血管平滑肌细胞中转染miR-211模拟物(miR-211 mimics),流式细胞术检测细胞凋亡。生物信息学数据库预测miR-211的靶基因,荧光素酶报告系统鉴定miR-211和Bax的靶向关系。蛋白质印迹法(Western blotting)检测转染miR-211 mimics对细胞中Bax蛋白表达影响。在血管平滑肌细胞中转染miR-211 mimics和Bax过表达载体(pcD⁃NA3.1-Bax),流式细胞术测定凋亡,Western blotting测定Bax蛋白表达。结果miR-211在颅内动脉瘤中表达下调,Bax在颅内动脉瘤中表达上调。转染miR-211 mimics后的血管平滑肌细胞中miR-211表达水平升高,细胞凋亡率降低[(26.58±2.14)%比(28.41±2.35)%比(13.54±1.17)%,P<0.05],细胞中Bax蛋白表达水平下降。miR-211靶向抑制血管平滑肌细胞中Bax蛋白表达。pcDNA3.1-Bax提高上调miR-211后的血管平滑肌细胞中Bax蛋白表达水平,促进细胞凋亡[(12.47±1.58)%比(23.71±2.24)%,P<0.05]。结论miR-211在颅内动脉瘤中表达下调,miR-211通过靶向Bax抑制血管平滑肌细胞凋亡。

Objective To investigate the expression of microRNA-211(miR-211)in intracranial aneurysms and its effect on the apoptosis of vascular smooth muscle cells.Methods From May 2017 to January 2019,50 cases of intracranial aneurysm tissues were surgically removed from the First Affiliated Hospital of Chengdu Medical College.At the same time,20 cases of normal intracranial ar⁃tery vascular tissues were selected during the same period.Patients with traumatic brain injury.Quantitative real-time polymerase chain reaction(qRT-PCR)method was used to determine the expression changes of miR-211 and Bcl-2 related X protein(Bax)in intra⁃cranial aneurysms.The miR-211 mimics was transfected into aneurysm vascular smooth muscle cells,and apoptosis was detected by flow cytometry.The bioinformatics database predicted the target genes of miR-211,and the luciferase reporter system identified the tar⁃get relationship between miR-211 and Bax.Western blotting was used to detect the effect of transfection of miR-211 mimics on Bax pro⁃tein expression in cells.The vascular smooth muscle cells were transfected with miR-211 mimics and Bax overexpression vector(pcD⁃NA3.1-Bax),apoptosis was determined by flow cytometry,and Bax protein expression was determined by Western blotting.Results miR-211 was down-regulated in intracranial aneurysms,and Bax was up-regulated in intracranial aneurysms.The expression level of miR-211 in vascular smooth muscle cells transfected with miR-211 mimics increased,and the rate of apoptosis decreased[(26.58±2.14)%vs.(28.41±2.35)%vs.(13.54±1.17)%,P<0.05],in cells The expression level of Bax protein decreased.miR-211 targets the inhi⁃bition of Bax protein expression in vascular smooth muscle cells.pcDNA3.1-Bax increases the expression of Bax protein in vascular smooth muscle cells after up-regulation of miR-211,and promotes cell apoptosis[(12.47±1.58)%vs.(23.71±2.24)%,P<0.05].Conclu⁃sion miR-211 is down-regulated in intracranial aneurysms,miR-211 inhibits vascular smooth muscle cell apoptosis by targeting Bax.