PGDFR-β/GDNF信号通路介导星形胶质细胞调控脑缺血后血脑屏障的功能恢复  

Astrocytes promotes the recovery of blood-brain barrier disruption after ischemic stroke via PDGFR-β/GDNF signaling pathway

作　　者：申杰 徐桂华 Shen Jie;Xu Guihua(Department of Neurology,Dongguan Binhaiwan Central Hospital(DongguanAffiliated Hospital of Jinan University),DongguanGuangdong 523900)

机构地区：[1]广东省东莞市滨海湾中心医院(暨南大学附属东莞医院)神经内科,523900 [2]广东省东莞市滨海湾中心医院(暨南大学附属东莞医院)东科教科,523900

出　　处：《卒中与神经疾病》2022年第2期110-116,共7页Stroke and Nervous Diseases

基　　金：东莞市社会发展科技项目(20211800904462)。

摘　　要：目的探讨血小板源性生长因子受体β(Platelet-derived growth factor receptor-β,PDGFR-β)/血小板源性生长因子(Platelet-derived growth factor,PDGF)信号通路在介导星形胶质细胞调控脑缺血后血脑屏障(Blood-brain barrier,BBB)功能恢复的分子机制。方法利用siRNA尾静脉注射干扰星形胶质细胞胶质纤维酸性蛋白(Glial fibrillary acidic protein,GFAP)的基因表达;利用插线法制作脑缺血再灌注模型;免疫组织荧光染色分析GFAP基因干扰后星形胶质细胞的数量变化;利用绿色荧光示踪剂渗透实验分析GFAP基因干扰后BBB渗透性改变;利用苏木精-伊红染色法(Hematoxylin-eosin staining,HE)分析GFAP基因干扰后脑微出血改变。在PDGFR-β生后全身性基因敲除鼠(Estrogen-knockout,Esr-KO)诱导脑缺血模型,利用免疫印迹试验分析GDNF的表达水平;脑室泵入外源性GDNF之后分析脑缺血后脑水肿形成、神经功能恢复及内皮细胞紧密连接蛋白水平的变化。结果于缺血第14 d GFAP siRNA预处理小鼠缺血边缘区的Vimentin+星形胶质细胞数量减少、荧光强度增高、微出血体积增大;于缺血第14 d Esr-KO鼠缺血边缘区GDNF蛋白表达明显减少;侧脑室注射GDNF可部分减轻Esr-KO鼠脑水肿严重程度、促进神经功能恢复,且可部分增加Esr-KO鼠缺血边缘区紧密连接蛋白表达。结论PDGFR-β/GDNF信号通路对于介导星形胶质细胞调控脑缺血后BBB功能恢复方面有十分重要的作用,可能成为今后脑缺血继发脑水肿的又一新的治疗靶点。Objective To investigate the mechanisms of astrocytes in regulating blood-brain barrier functional recovery after ischemic stroke via PDGFR-β/GDNF signaling pathway.Methods The expression of GFAP in astrocytes was interfered by intravenous tail injection with siRNA,and the mouse model of cerebral ischemia-reperfusion was established by intra-arterial suture occlusion of the middle cerebral artery.After GFAP siRNA injections,the number of astrocytes was analyzed by immunofluorescence staining,BBB permeability was analyzed by green fluorescent tracer penetration test,and cerebral microbleeds was analyzed by hematoxylin and eosinstaining(H-E staining).The model of cerebral ischemia-reperfusion was induced in postnatally induced systemic PDGFR-βknockout mice(Esr-KO),the expression of glial derived neurotrophic factor(GDNF)was analyzed by Western blotting.After intraventricular injection of exogenous GDNF,brain edema,neurological function and the expression of endothelial tight junction proteins were analyzed.Results Fourteen days after ischemia,decreased number of vimentin positive astrocytes,increased fluorescentintensity and increased microbleeding volume were seen at ischemic borders of GFAP siRNA-pretreated mice.In addition,the expression of GDNF protein was significantly decreased in ischemic borders of Esr-KO mice.Intracerebroventricular injection of GDNF could partly reduce the formation of brain edema and promote the recovery of neurological function in Esr-KO mice,and partially increase the expression of tight junction proteins near the ischemic borders of Esr-KO mice.Conclusion PDGFR-β/GDNF signaling pathway may play a vital role in astrocyte regulation of BBB functional recovery,which may be a new therapeutic target for decreasing brain edema after ischemic stroke in the future.

关 键 词：血小板源性生长因子受体β 胶质细胞源性神经营养因子 星形胶质细胞 血脑屏障 周细胞 

分 类 号：R743.3[医药卫生—神经病学与精神病学]