骨髓间充质干细胞在多发性硬化中对水通道蛋白-4介导的血脑屏障通透性的影响及其机制

项目名称： 骨髓间充质干细胞在多发性硬化中对水通道蛋白-4介导的血脑屏障通透性的影响及其机制

项目编号： No.81501029

项目类型： 青年科学基金项目

立项/批准年度： 2016

项目学科： 医药、卫生

项目作者： 刘艳群

作者单位： 中国人民解放军第二军医大学

项目金额： 17.5万元

中文摘要： 多发性硬化（MS）仍缺乏有效的治疗手段。骨髓间充质干细胞（MSCs）移植有望成为其有效的治疗手段；维持血脑屏障（BBB）的完整性是多发硬有效的治疗靶点。本申请人的研究结果表明，MSCs 能下调缺血及炎症诱导的水通道蛋白-4（AQP4）的表达，减轻血脑屏障的破坏，p38信号通路可能参与其中，但其确切机制仍不甚清楚, MSCs在维持多发性硬化BBB完整性中的作用及机制仍无报道。本项目拟以实验性自身免疫性脑炎小鼠和原代星形胶质细胞为研究对象，采用Evans Blue 渗漏实验，增强MRI扫描，星形胶质细胞特异性病毒干扰，免疫组化，蛋白电泳等方法，通过体内实验和体外实验，探讨MSCs移植对EAE小鼠AQP4表达以及BBB通透性的影响，阐明腺苷A2BR在其中发挥的作用，明确腺苷A2BR-p38信号通路对于AQP4表达的影响，为MSCs在MS中的治疗作用提供新的理论基础，为MS的治疗提供新的思路。

中文关键词： 多发性硬化；血脑屏障；星形胶质细胞；神经炎症；水通道蛋白-4

英文摘要： Mesenchymal stem cells (MSCs) replacement is a providing hope for multiple sclerosis (MS), a disease lacks effective therapeutic methods；maintain the integrity of blood-brain barrier (BBB) might be a potent therapeutic target of MS. Our previous study indicated that MSCs downregulated AQP4 expression effectively, thus maintained BBB integrity and reduced edema after cerebral ischemia, p38 pathway might participate in the regulation of AQP4 expression. However, the exact mechanism is still unclear. In addition, activating adenosine A2B receptor (A2BR) expressed on astrocyte promotes the phosphorylation of p38 and increased the secretion of inflammatory factors. In multiple sclerosis, effects of MSCs on the permeability of BBB were still unknown. In this research, we intend to explore role of MSCs on the permeability of BBB and illustrate the therapeutic mechanism. Using Evan Blue extravation and enhanced-MRI scan，astrocyte-specific interference test, western blot, immunostaining and so on ,we first explore effects of MSCs on AQP4 expression and the integrity of BBB in experimental autoimmune encephalomyelitis (EAE) mice, then, using primary astrocyte culture model, we try to explore whether adenosine A2B receptor participate in the regulation of AQP4 expression and astrocyte function and the relationship between the activation of adenosine A2B receptor and p38 phosphorylation. Finally, we verify the effects of adenosine A2BR-p38 signal pathway on the regulation of AQP4 expression and BBB integrity. Our project provides a new therapeutic mechanism of MSCs transplantation and might offer a new view on MS therapy.

英文关键词： multiple sclerosis ;blood-brain barrier;astrocyte;neuroinflammation;aquaporin-4