神经干细胞移植联合腹腔注射促红细胞生成素对横断性脊髓损伤大鼠神经轴突的修复作用

目的: 探讨神经干细胞(NSCs)与促红细胞生成素(EPO)共同作用于横断性脊髓损伤大鼠后对损伤区轴突的修复作用,为临床治疗脊髓损伤提供理论依据。方法: 40只雌性成年Wistar大鼠,建立T10全横断大鼠脊髓损伤模型后,随机分为对照组、NSCs组、EPO组和联合治疗组,每组10只。术后8周采用BDA皮质脊髓束顺行追踪法和荧光金(FG)皮质脊髓束逆行追踪法评估损伤区脊髓神经轴突再生情况,同时分期采用实验性脊髓损伤运动功能BBB评分法评价大鼠后肢功能恢复情况。结果: BDA 免疫荧光染色和FG免疫荧光染色,联合治疗组可见大量被BDA-cy3红色荧光标记的再生轴突,其中部分再生轴突穿越损伤区到达远端;NSCs组仅见少量轴突再生,无神经轴突通过脊髓损伤区;EPO组偶见散在的神经纤维再生;对照组无明显的轴突再生。联合治疗组大脑皮质中可见少量被FG标记的椎体细胞及轴突发出金黄色荧光,其余3组大脑皮质中无FG标记细胞。大鼠后肢功能BBB评分,在术后1周及1周以后各时段,联合治疗组大鼠BBB评分均高于其他各组(P<0.05)。结论: 脊髓损伤后移植NSCs联合腹腔注射EPO可有效促进脊髓损伤区神经轴突的再生以及脊髓损伤大鼠后肢运动功能的恢复。

Repair effect of neural stem cells transplantation combined with intraperitoneal injection erythropoietin for axons in adult rats with transected spinal cord injury

Objective To investigate the repair effect of neural stem cells(NSCs) and erythropoietin (EPO) on the axonal regeneration of the rats with transected spinal cord injury in spinal cord injury area, and to provide theoretical basis for the clinical treatment of spinal cord injury. Methods Forty Wistar rats with T10 spinal cord transaction were randomly divided into control group, NSCs group, EPO group and NSCs+EPO group(n=10).BDA anterograde corticospinal cord neuronal tracing and fluoro-gold(FG) retrograde tracing were carried out at the 8th week after operation to observe the regeneration of nerve fibers.The BBB locomotion score was used to evaluate the restoration after operation in the rats with spinal cord transaction. Results The BDA immunofluorescence staining and FG immunofluorescence staining results showed that a large amount of regenerated axons were observed in NSCs+EPO group, which were labeled by BDA-cy3 red fluorescence, and some regenerated axons got through the injuried area.While in NSCs group, only a small amount of regenerated axons were observed after spinal cord injury, and no regenerated axons got through the injuried area.In EPO group, only sporadically regenerated nerve fibers were observed occasionally, while in control group, no axonal regeneration was observed.In NSCs+EPO group, a small amount of cones and axons, which were labeled by FG fluorescence, emitted golden yellow fluorescence, and no cells labeled by FG was observed in other groups.The BBB scores in NSCs+EPO group 7 d after operation and at different time later were higher than those in other groups(P<0.05). Conclusion Transplantated NSCs and intraperitoneal injection of EPO could promote axon regeneration in spinal cord injury zone and hind limb motor function recovery of the rats with spinal cord injury.