神经断离处移植间充质祖细胞延缓骨骼肌萎缩

Delay of skeletal muscle atrophy after transplantation of mesenchymal progenitor cells into transected position

目的探讨间充质祖细胞(MPC)移植于神经断离处延缓失神经性骨骼肌萎缩。方法取GFP转基因C57小鼠后肢长骨进行MPC培养及鉴定。选取C57小鼠36只,随机分为MPC移植组、神经断离组及对照组,MPC移植组坐骨神经断离处注入5μL MPC悬液,神经断离组注入等量PBS,对照组不作处理。观察小鼠后肢活动能力,术后2和4周测量腓肠肌湿重、肌纤维横截面积维持率及观察超微结构,用Western blot检测α-actin、MHC及RT-PCR检测Myogenin、MyoD的表达。结果术后2和4周,MPC移植组腓肠肌湿重及肌纤维横截面积维持率显著高于神经断离组(P<0.05);术后4周,MPC移植组肌细胞核、线粒体、内质网的退变及肌肉纤维化程度明显低于神经断离组,α-actin、MHC、Myogenin、MyoD表达强度显著高于神经断离组(P<0.05)。结论异体间充质祖细胞体内移植可有效延缓失神经肌肉萎缩。

Objective To study the delaying denervated skeletal muscle atrophy after transplantation of mesenchy- mal progenitor cells （MPCs） into the transected position. Methods MPCs were isolated from bones of hind limbs of GFP transgenic C57 mice for cultivation and identification. 36 C57 mice were divided into 3 groups evenly in random, MPC transplantation group, the transeeted group and the control group. 5 μL of MPC suspension and 5 μL of Phosphate buffered saline （PBS） were injected into the sciatic nerve transected position in the MPC trans- plantation group and the transected group respectively while nothing was injected in the control group. The activity ability of hind limbs of mice were observed. At the time point of 2 and 4 weeks after the operation, the retain ratio of wet weight of gastrocnemius muscle and cross sectional area of muscle fiber was measured and the uhrastructural organization was observed. The expression of α-actin, myoglobulin （MHC） were detected by Western blot and the expression of Myogenin and MyoD were detected by RT-PCR. Results At the time point of 2 and 4 weeks after the operation, the wet weight of gastrocnemius muscle and the retain ratio of cross sectional area of muscle fiber of mice of the MPC transplantation group was higher than that of the transected group significantly （P 〈 0. 05 ）. At the time point of 4 weeks after the operation, compared with the degeneration of myocyte, mitochondria and sarcoplasmic re- ticulum and the extent of musculus fibrosis of the transected group, that of the MPC transplantation group were low- er significantly while compared with the the expression of ct-actin, MHC, Myogenin and MyoD of the transected group, that of the MPC transplantation group were higher significantly（P 〈 0.05）. Conclusions The transplanta- tion in vivo of allogenic mesenchymal progenitor cells is effective for delaying denervated muscle atrophy.