神经干细胞移植对脑挫伤大鼠神经功能恢复神经元存活和轴突再生的影响

目的 观察神经干细胞(NSCs)移植对脑挫伤大鼠神经功能恢复影响,并探讨其机制.方法 24只SD大鼠以投币法分为3组:假手术组、手术组和NSCs移植组.采用自由落体致大鼠皮质运动区脑损伤模型,将培养纯化并鉴定的NSCs于术后当天移植入损伤位点周围;术后0d、3d、7d、14d行神经功能缺失(NSS)评分,观察动物运动和平衡功能缺损与恢复情况;14d时取脑组织用免疫荧光技术检测hochest标记的移植NSCs在体内存活、迁移;用神经元核蛋白(NeuN)、生长相关蛋白(GAP-43)抗体检测并计数宿主神经元存活和局部轴突再生.结果 与假手术组比较,脑外伤组大鼠脑挫伤后即出现不同程度抽搐,瘫痪,平衡功能缺失.神经功能缺损评分较假手术组明显升高,并随时间推移有所降低.而NSC移植组的NSS评分至第7天后与单纯手术组比较有明显减少[(4.38±0.74)分,(5.50±1.07)分,P＜0.01].Ho-chest标记的移植NSCs能在宿主脑组织存活,并向四周迁移.免疫组化染色显示宿主NeuN阳性神经元[(51.46±3.303)个,(42.83±5.401)个,P＜0.01]和GAP-43阳性纤维数量[(13.3±1.7)个,(8.7±1.1)个,P＜0.01]在NSC移植组明显增多.结论 NSCs移植能在挫伤脑组织存活、迁移,并促进宿主神经元存活、局部轴突再生和改善脑挫伤大鼠神经功能.

Effect of neural stem cells transplantation on the neurological function improvement and local neuronal survival and axonal regeneration in traumatic rat brain

Objective To research the effects of neural stem cells (NSCs) transplantation on the neurological function improvement and neural survive and axonal regeneration in traumatic rat brain. Methods NSCs were cultured in vitro, labeled with hochest and transplanted into rat brain injured area by weight-dropping. Neurological severity scores(NSS) tested the functions at the 0,3,7,14 day post-injury. Immunofluorescence was used to detect the expressions of NeuN cells and GAP-43. Results There was significant difference in NSS between NSCs transplantion group and brain injury group(4.38 ±0.74 vs 5.50 ± 1.07, P＜0.01) at 7th day. There were a significant increase in neural number (51.46 ± 3. 303 vs 42.83 ± 5. 401, P ＜ 0.01 ) ), and GAP-positive axons ( 13.3 ± 1.7 vs 8.7 ± 1.1, P＜0.01 ) in NSCs transplantion group than in control group. Conclusion NSCs have an effects on the neurological improvement in brain injured rat. This may be associated to the increase in number of the neurons and local axons.