经静脉骨髓间充质干细胞移植对脑梗死大鼠脑组织的保护作用

目的:探讨经静脉间充质干细胞(MSCs)移植对大鼠脑梗死体积的影响以及其向神经元细胞的转化和定向迁移情况。方法:对同种异体SD大鼠的MSCs进行体外分离、培养。应用大脑中动脉线栓栓塞法(MCAO)制作大鼠脑梗死模型。应用TTC染色法测定大鼠脑梗死体积。将SD大鼠分为MSCs静脉移植组和对照组。应用免疫组化法在梗死后测定NSE、NF-M和GFAP的表达。电子显微镜观察各组大鼠脑组织突触超微结构。结果:与对照组相比,经静脉MSCs移植可以减小缺血再灌注大鼠的脑梗死体积。经静脉移植MSCs2周后神经元样细胞的NSE、NF-M染色为阳性。而未分化的MSCs为阴性。GFAP染色为阴性。MSCs组和对照组电镜可见部分突触肿胀,微管和微丝断裂、排列紊乱,有些突起内见有絮状物,突触前膜和突触后膜肿胀,突触间隙模糊不清。和对照组相比,MSCs组突触界面曲率、突触后致密物质的厚度较大、突触间隙宽度较窄、突触活性带长度较长。结论:实验结果证明脉移植MSCs可以减小大鼠脑梗死体积,经静脉移植MSCs可定向迁移至脑梗死去并可向神经元转化,但并不转化为神经胶质细胞。此外静脉移植间充质干细胞可减轻神经元突触超微结构的损伤性改变,进一步证明了经静脉移植间充质干细胞对脑梗死的治疗作用。

Treatment of Cerebral Infarction with Intravenous Administration of Bone Marrow Stromal Cells in Rats

Objective:To observe the effect of intravenous administration of bone marrow stromal cells (MSCs) on the structural changes after acute cerebral infarction.Methods:SCs harvested from adult Sprague—Dawley rats were isolated,cultured and purified.A rat model of transient middle cerebral artery occlusion (MCAO) and reperfusion was used and the infarction volume was measured by 2,3,5-triphenyltetrazolium chloride (TTC)-staining.The distribution and expression of neuronspecific enolase(NSE)、neurofilament (NF-M),and glial fibrillary acidic protein(GFAP)were detected by immunochemistry.The ultrastructure of synapse was observed by electronmicroscope.Results:In contrast to the cases treated with vehicle,the infarct volume was significantly reduced by administration of bone marrow stromal cells intravenously.The morphology of MSCs change into neuron-like cells,positive NSE wa(s85.3±4.2)%,that of NF-M(89.2 ±3.4)%,but that of GFAP was negative.The change of ultrastructual of synapse of MSCs treatment group was light than vehicle treatment group.Conclusions:With intravenous administration of MSCs after cerebral infarction injury,MSCs could migrate and survive into infarction region.