不同来源成体神经干细胞促进大鼠脊髓损伤功能修复的比较研究

目的 评价大脑、骨髓和脂肪组织3种不同来源的神经干细胞对大鼠脊髓挫伤的治疗效果.方法 选取来源于同一大鼠成体中大脑、骨髓和脂肪的3个部位的组织,分离、诱导分化为不同来源的神经干细胞;应用自由落体损伤模型装置造成大鼠脊髓挫伤.将不同来源的神经干细胞分别移植入大鼠脊髓损伤部位,通过BBB评分比较修复脊髓损伤功能的效果,应用免疫荧光染色检测不同移植细胞在损伤脊髓中的存活、分布、迁移的情况.另设假手术对照组和生理盐水对照组.结果 与假手术对照组和生理盐水对照组比较,3个细胞处理组BBB评分在2～8周开始增加,9周以后更加明显,差异开始有统计学意义(P<0.05).在移植后1周和4周,细胞移植组中脑源性神经干细胞(SVZ-NSs)组Brdu/nestin+>神经元存活的数目明显高于其他2组.但差异没有统计学意义(P>0.05);到了第8周,3组均仅有少量Brdu/nestin+>细胞存活,相互之间比较差异无统计学意义(P>0.05).结论 植入来源于大脑、骨髓和脂肪组织的神经干细胞都可以在一定程度上提高脊髓损伤后运动功能恢复,但SVZ-NSs组的脊髓损伤大鼠运动功能恢复要比脂肪来源的神经干细胞(AD-NSs)组及骨髓来源的神经干细胞(BM-NSs)组更好.AD-NSs由于来源广泛和强有力的增殖能力,相比其他来源的神经干细胞,可能是更好的选择.

Comparison of the effect of adult neural stem cells derived from different origins in treatment of rat spinal cord injury

Objective To evaluate the therapeutic effects of adult neural stem cells derived from the brain, adipose tissue and bone marrow on spinal cord injuries in adult rats. Methods The brain subventricular zone (SVZ), adipose tissue and bone marrow from the same rat were obtained to induce the neural stem cells (NSCs). In 72 SD rats with spinal contusive injury, the NSCs from the 3 origins were grafted into the injured spinal cord one week after the injury, with 24 rats as the saline control group and another 24 as the sham-operated group. The locomotor recovery of the rats was evaluated according to the BBB scores, and the cell survival, distribution, migration and differentiation in the injured spinal cord were evaluated by immunohistochemistry. Results Compared with the rats in sham-operated and saline groups, the rats receiving transplantation of NSCs of different origins all showed significantly increased BBB scores. At 9 weeks after the transplantation, the rats receiving brain SVZ-derived NSCs (SVZ-NSs) exhibited significantly improved locomotor function compared with those grafted with the other two NSCs (P<0.05). The SVZ-NSs showed significantly higher Brdu/nestin+cell percentage than bone marrow-derived NSCs(BM-NSs) and adipose-derived NSCs(AD-NSs) at 4 weeks after grafting, but till 8 week after the grafting, only a few positive cells were found in the injured spinal cord in the 3 groups, without significant difference between them (P>0.05). Conclusion Grafting of the NSCs derived form the brain SVZ, adipose tissue and bone marrow all help improve the locomotor recovery of the rats following spinal cord injury, and the SVZ-NSs has the most obvious effect. But AD-NSs may seem a better option than those of other origins for repairing the injured spinal cord due to their abundant sources and strong proliferation ability.s