人脐带间充质干细胞修复大鼠坐骨神经损伤的实验研究

Experimental Study on the Reparation of Rat's Sciatic Nerve Injury by Human Umbilical Cord Mesenchymal Stem Cells

目的观察人脐带间充质干细胞(hUC-MSCs)在体内微环境中修复大鼠坐骨神经损伤的效果。方法取80只SD大鼠,制作羊膜管包绕的缺损10 mm的坐骨神经损伤模型。将大鼠随机分为实验组和对照组,每组各40只,实验组羊膜管内注入hUC-MSCs悬液50μL(1.0×105/mL),对照组注入等量的DF12培养基。分别于术后4、8、12、16、20周行肢体一般状态、腓肠肌湿质量恢复率检测。结果 2周后术侧足底踝关节负重区出现红肿及溃疡,5～10周时各组大鼠术侧肢体溃疡逐渐愈合,对照组较实验组红肿及溃疡程度严重,且愈合较慢;实验组术侧腓肠肌恢复率随时相延长而逐步好转,而对照组则逐步下降,2组间差异有统计学意义(P<0.01)。结论直接植入体内的hUC-MSCs可分化神经样细胞,对坐骨神经损伤可起修复作用。

Objective To observe the effects of human umbilical cord mesenchymal stem cells（hUC-MSCs） on reparation of rat′s sciatic nerve injury in the micro-environment in vivo,and to provide the experimental basis for the clinical treatment of sciatic nerve injury.Methods The sciatic nerve stem in the right thigh of each rat was exposed and encapsuled by amniotic membrane.A 10 mm sciatic nerve defect was made by cutting 10 mm-length of sciatic nerve stem,forming an amniotic tube.80 SD rats were divided into two groups randomly：a group of rats whose amniotic tubes were injected with hUC-MSCS（experimental group,n =40） and a group of rats whose amniotic tubes were injected with normal saline（control group,n =40）.50 μL of cell suspension（cell quantity：1.0×105/mL） was injected into the amniotic membrane tubes in the experimental group and the same amount of DF12 medium was injected into the amniotic tubes in the control group.The general state of limbs,recovery rate of gastrocnemius muscle wet weight were observed 4,8,12,16 and 20 weeks after operation,respectively.Results Two weeks later,the weight-bearing area of the right sole of foot and ankle turned red and swollen,and ulcers were found.The ulcers in each injured leg healed gradually 5 to 10 weeks after operation.But the changes were more severe in the control group and the traumatic surfaces healed more slowly than experimental group.Recovery rate of gastrocnemius muscle wet weight increased gradually over time in the experimental group,but decreased gradually in the control group.Differences between the two groups at different phases were statistically significant（P 〈 0.01）.Conclusions The implanted hUC-MSCSs in vivo can differentiate into neron-like cells and exert positive effects on the reparation of sciatic nerve injury.