骨髓间充质干细胞移植对大鼠脊髓损伤后功能恢复的影响

目的 观察骨髓间充质干细胞(MSCs)移植对脊髓损伤修复的促进作用.方法 用改良Allen法制作大鼠脊髓损伤动物模型.随机分成对照组(A组),脊髓损伤9 d后脊髓内微量注射生理盐水溶液5μl;骨髓间充质干细胞移植组(B组),脊髓损伤9 d后脊髓内注射骨髓间充质干细胞悬液5μl.移植后7、14、28 d采用斜板实验、脊髓运动功能BBB评分法观察大鼠运动功能恢复情况,脊髓诱发电位的检测观察神经功能恢复,苏木素-伊红(HE)染色观察脊髓损伤处空洞面积的改变情况,免疫组织化学法观察移植的骨髓间充质干细胞的存活及分化情况,损伤部位神经纤维的再生情况.结果 移植后28 d,两组斜板倾斜角度差异有统计学意义[A组(44.96±5.70)度,B组(53.19±6.51)度,P＜0.05];两组BBB评分差异有统计学意义[A组(6.8±1.2),B组(10.1±3.5),P＜0.05].同时,两组MEP潜伏期差异有统计学意义[A组(4.69±0.47)ms,B组(3.97±0.83)ms,P＜0.05],两组SEP潜伏期差异有统计学意义[A组(4.19±1.97)ms,B组(2.60±0.92)ms,P＜0.05].两组神经轴突计数差异有统计学意义[A组(32.8±6.1)条/mm2,B组(39.0±4.6)条/mm2,P＜0.05].实验组可见明显星形胶质细胞和神经纤维再生,脊髓损伤处的空洞面积明显减小.结论 骨髓间充质干细胞可在脊髓损伤处分化为神经元和神经胶质细胞,能够减小脊髓损伤处的空洞面积,促进受损轴突的再生和运动功能的恢复.

The effects of mesenchymal stem cells transpiantation on the function recovery of rat with spinal cord injuries

Objective To investigate the promoting effects of mesenchymal stem cens(MSCs) transplantation on function recovery of rat spinal cord injuries(SCI).Methods rI'lle spinal cord of aduh rats was injured with modified Allen method,and the rats were randomly divided into 2 groups.The rats in the control group(group A)were subjected to the microinjection of saline solution(5μl)into the SCI site on the 9th day after SCI,and those in the experimental group(group B)were injected with MSCs(5μl).The inclined plane test and Basso,Beattie and Bresnahan locomotor rating scale(BBB scale)were used to observe the recovery of rats' behavioral function on the 7th,14th and 28th day after the transplantation.spinal evoked potential tests were used to observe the recovery of spinal cord neural function,bematoxylin-eosin(HE)staining to reflect the change of cavity volume,and immunohistochemical metllod to observe the survival of transplanted MSCs and regeneration of damaged nerve fibers.Results On the 28th day after transplantmion.there was significant difference in inclined plane critical point between groups A and B[(44.96±5.70)°vs(53.19±6.51)°,P＜0.05].On the 28th day after transplantation,BBB scale had significant difference between groups A and group B(6.8±1.2 vs 10.1±3.5,P＜0.05).Onthe 28th day after transplantation,MEP and SEP latencies had significant differences.The MEP latencies in groups A and B were(4.69±0.47)ms and(3.97±0.83)ms,respectively(P＜0.05),and the SEP latencies in groups A and B were(4.19±1.97)ms and(2.60±0.92)ms respectively(P＜0.05).On the 28th day after transplantation,nerves axons count(strip/mm2)showed significant difference between groups A and B(32.8±6.1 vs 39.0±4.6,P＜0.05).In group B,there was significant regeneration of astrocytes and nerve fiber,and cavity volume of the injured site was significantly reduced.Conclusion MSCs can differentiate into neurons and astrocytes,reduce cavity volume,promote axonal regeneration and improve functional recovery.