骨髓间充质干细胞经BDNF基因修饰后移植治疗大鼠半横断脊髓损伤的电生理研究

目的采用电生理的研究方法,观察脑源性神经营养因子(BDNF)基因修饰的骨髓间充质干细胞对脊髓损伤的修复作用。方法随机将大鼠分成3组:空白组10只(只切除椎板,暴露脊髓硬脊膜);SCI组10只;SCI术后细胞移植组10只;从以上三组大鼠随机抽取8只于细胞移植后1 d、7 d、14 d、21 d、30 d、60 d进行SEP(皮层体感诱发电位)、MEP(运动诱发电位)等电生理检测技术,并观察大鼠的运动评分恢复程度。结果细胞移植4d后,大鼠饮食和活动开始增加;后肢变化过程如下:损伤后1~4 d损伤侧后肢迟缓性瘫痪,拖地行走,损伤对侧后肢由损伤初期的运动减弱逐渐恢复,损伤后5~9 d损伤侧后肢痉挛性瘫痪;10~14 d损伤侧下肢恢复少量活动,损伤对侧后肢恢复至较损伤前稍弱的状态;15~21 d损伤侧后肢活动能力较之前有明显改善,至30 d损伤侧后肢活动能力及肌张力恢复程度最明显,30 d以后无更明显改善。免疫组化发现损伤处诱导标记的骨髓间充质干细胞存活,行为学观察发现细胞移植改善了损伤大鼠运动能力。结论骨髓间充质干细胞经BDNF基因修饰后可以促进脊髓损伤大鼠的神经再生及部分传导功能恢复。

Electrophysiological study of BDNF gene-modified mesenchymal stem cell transplantation to repair transversely hemisectioned spinal cord injury in rats

Objective To study the effects of bone marrow mesenchymal stem cells modified by brain-derived neuro-trophic factor （ BDNF） gene on the repair of spinal cord injury by electrophysiological assay .Methods Thirty healthy Spra-gue-Dawley rats （male and female） were randomly divided into 3 groups：Blank group, 10 rats （removal of the lamina only and exposed spinal dura mater ）;spinal cord injury （SCI） group,10 rats;and cell transplantation after SCI group , 10 rats. Eight rats of them were selected randomly and detected their SEP and MEP , and evaluated the degree of recovery of motor scores in the rats at 1 d, 7 d, 14 d, 21 d, 30 d, and 60 d.Result Since 4 days after cell transplantation , the process of hind limbs changes was as follows：at the 1-4 days after injury , the injury side hind limb had flaccid paralysis , mopping the floor walk, the movement of contralateral hind limb was gradually recovered from the initial injury , the injury side hind limb had spastic paralysis in 5-9 days after SCI;during 10-14 days, the injury side had a few activities;the contralateral side re-covered to a less normal state;At 15-21 days, activities of the injury side improved obviously , until the 30th day.The activ-ity and muscle tension degree of the injury side recovered most obviously .After 30 days no more obvious improvement was ob-served.Immunohistochemistry showed that the transplanted mesenchymal stem cells , which were induced and labeled firstly , survived at the damage spinal cord , and behavioral observation found that the cell transplantation improved exercise capacity of the rats injured before .Conclusion Bone marrow mesenchymal stem cells modified by BDNF gene can partially promote the recovery of nerve transmission function and nerve regeneration .