骨髓间充质干细胞联合孕酮修复大鼠坐骨神经损伤的研究

Bone marrow mesenchymal stem cells combined with progesterone for repair of sciatic nerve injury in rats

目的 探讨骨髓间充质干细胞（BMSCs）与孕酮联合治疗大鼠坐骨神经损伤的疗效.方法 将健康成年清洁级雄性SD大鼠100只随机分为假手术组（对照组）和A、B、C、D5组,每组20只,建立大鼠右下肢坐骨神经损伤模型后,A组给予生理盐水,B、C、D组分别给予孕酮（8 mg/kg）、BMSCs移植、BMSCs移植联合应用孕酮（8 mg/kg）修复治疗.术后第12、24、48天采用Basso-Beattie-Bresnahan （BBB）评分法评估各组大鼠的右下肢运动功能恢复情况,术后48 d测定各组大鼠坐骨神经功能指数（SFI）,模型建立后0h和48 d取损伤坐骨神经行Western blot分析,检测损伤处脑源性神经营养因子（BDNF）、髓磷脂碱性蛋白（MBP）和生长相关蛋白-43（GAP-43）的蛋白表达水平.结果 术后48 d坐骨神经损伤组SFI值均逐渐恢复,D组的SFI值（1.21 ±0.12）明显优于A（12.37±0.28）、B（10.56 ±0.42）、C（6.58 ±0.34）组（P＜0.05）.手术当天坐骨神经损伤组的右下肢运动功能完全丧失呈迟缓性瘫痪,D组术后第12、24、48天的运动功能评分（12.65 ±0.95、16.39±1.02、18.19 ±2.00）均明显高于A（8.62±0.77、10.27士0.53、12.58±0.96）、B（9.98±0.81、13.48 ±0.65、15.13±1.28）、C（10.87±0.54、14.06±0.75、16.48±1.96）组,差异有统计学意义（P＜0.05）.手术当天A、B、C、D组的BDNF、MBP和GAP-43的蛋白水平较对照组明显降低（P＜0.05）;手术后第48天坐骨神经损伤组的上述蛋白水平均明显升高（P＜0.05）,其中D组的上述蛋白水平明显高于A、B、C组（P＜0.05）.结论 BMSCs联合孕酮治疗能够促进大鼠坐骨神经损伤的神经再生,促进大鼠运动功能的恢复,其机制可能与增加相应的神经组织BDNF、MBP和GAP-43的表达有关.

Objective To investigate the effects of bone marrow mesenchymal stem cells combined with progesterone for repairing sciatic nerve injury in rats.Methods 100 Adult male SD rats were equally divided into control group and groups A,B,C and D （model groups）.After rat sciatic nerve injury model was constructed in the model groups,group A,group B,group C and group D were given normal saline,progesterone （8 mg/kg）,bone marrow mesenchymal stem cell transplantation,bone marrow mesenchymal stem cells combined with progesterone （8 mg/kg）.At 12,24 and 48 day after sciatic nerve injury,functional outcome measurements were evaluated by the Basso-Beattie-Bresnahan （BBB） score.The protein levels of brain derived neurotrophic factor （BDNF）,myelin basic protein （MBP） and growth associated protein 43 （GAP-43） were detected by Western blotting after sciatic cord injury at 0 and 48 day.Results After 48 days,SFI values in model groups were gradually restored,but the SFI values in group D （1.21 ± 0.12） were significantly higher than in group A （12.37 ±0.28）,group B （10.56 ±0.42） and group C （6.58 ±0.34,P ＜0.05）.The dual hind limb motor functions were completely lost with flaccid paralysis in the model groups in the day of surgery.The motor function scores in group D on the postoperative day 12,24,and 48 （12.65 ±0.95,16.39 ± 1.02,and 18.19 ±2.00 respectively） were significantly higher than in group A （8.62 ±0.77,10.27 ±0.53,and 12.58 ±0.96）,group B （9.98 ±0.81,13.48 ± 0.65,15.13 ± 1.28） and group C （10.87±0.54,14.06 ±0.75,16.48 ± 1.96,P ＜0.05 for all）.The MBP,BDNF and GAP-43 protein levels in the day of surgery in the model groups were significantly lower than in the control group （P ＜ 0.05）.These protein levels were significantly higher on the postoperative day 48 （P ＜ 0.05）,and those in group D were significantly higher than in groups A,B and C （P ＜ 0.05）.Conclusion Bone marrow mesenchymal stem cells combined with progesterone can promote the regeneration of rat sciatic nerve injury and recovery of motor function,which may be associated with the increases of BDNF,MBP and GAP-43 in the corresponding nerve tissues.