miR-21对缺血/再灌注后血脑屏障的保护作用与机制  

The protective effect and mechanism of miR-21 on the blood-brain barrier after ischemia/reperfusion

作　　者：陈志强[1] 邵帅 王建 李利[1] CHEN Zhi-qiang(Department of Neurosurgery, The Fourth Affiliated Hospital of Harbin Medical University, Harbin 150001, China)

机构地区：[1]哈尔滨医科大学附属第四医院神经外科,黑龙江哈尔滨150001

出　　处：《牡丹江医学院学报》2021年第6期6-9,107,共5页Journal of Mudanjiang Medical University

基　　金：黑龙江省卫生计生委科研课题(2018373)。

摘　　要：目的探究miR-21对缺血/再灌注后血脑屏障保护作用与机制。方法采用线栓法构建并验证雄性SD大鼠脑缺血/再灌注模型。实验随机分为空白质粒组、miR-21-mimic组和miR-21-inhibitor组(n=6)。利用Western Blot检测大鼠大脑皮层组织中Bax蛋白的表达变化,免疫荧光检测大脑皮层组织中自噬相关蛋白LC-3的分布情况,9.4T磁共振测量比较不同时间大鼠脑梗死体积。结果Western Blot实验结果显示:与空白质粒组相比,给予miR-2l-mimic的大鼠脑组织中Bax蛋白与AQP4蛋白的表达显著降低(P<0.05),而给予miR-21 inhibitor的大鼠脑组织中Bax蛋白的表达升高(P<0.05);免疫荧光结果显示:与空白质粒组比较,miR-21-mimic组中自噬相关蛋白LC-3表达降低(P<0.05),而miR-21 inhibitor组中LC3蛋白的分布增加(P<0.05);核磁共振结果显示:与空白质质粒组比较,miR-21-mimic组的脑梗死体积最小(P<0.05)。结论miR-2l可能通过下调Bax蛋白的表达抑制细胞凋亡或通过抑制自噬保护血脑屏障,减少脑梗死体积;miR-21有望作为缺血/再灌注后血脑屏障治疗的靶点。To explore the protective effect and mechanism of miR-21 on the blood-brain barrier after ischemia/reperfusion.Methods The suture method was used to construct and verify the cerebral ischemia/reperfusion model of male SD rats.We randomly divided the experiment into blank plasmid group,miR-21-mimic group,and miR-21-inhibitor group(n=6).Western Blot was used to detect the expression of Bax protein in rat cerebral cortex,immunofluorescence was used to detect the distribution of autophagy-related protein LC-3 in cerebral cortex,and 9.4T magnetic resonance measurement was used to compare rat cerebral infarct volume at different times.Results Western Blot experiment results showed that compared with the blank plasmid group,the expression of Bax protein and AQP4 protein in the brain tissue of rats given miR-2l-mimic was significantly reduced(P<0.05),while the expression of Bax protein in the brain tissues of rats given miR-21 inhibitor increased(P<0.05);Immunofluorescence results showed that compared with the blank plasmid group,the expression of autophagy-related protein LC-3 in the miR-21-mimic group decreased(P<0.05),while the distribution of LC3 protein in the miR-21 inhibitor group increased(P<0.05);MRI results showed that,compared with the blank plasmid group,the miR-21-mimic group had the smallest cerebral infarction volume(P<0.05).Conclusion miR-21 may inhibit cell apoptosis by down-regulating the expression of Bax protein or protect the blood-brain barrier by inhibiting autophagy and reduce the volume of cerebral infarction;miR-21 is expected to be a target for blood-brain barrier therapy after ischemia/reperfusion.

关 键 词：血脑屏障 MIR-21 保护作用 保护机制 

分 类 号：R743.3[医药卫生—神经病学与精神病学]