Effect of transplantation of myogenically induced bone marrow-derived mesenchymal stem cells on denervated muscle atrophy / 中国组织工程研究

ABSTRACT

AIM:To observe the myogenic effect of bone marrow-derived mesenchymal stem cell(MSC)transplantation after chemical-induction and stress-induction on denervated skeletal muscle atrophy in vivo. METHODS:The experiment was performed at the Animal Experimental Center and Central Laboratory in Xinhua Hospital affiliated to Shanghai Jiao Tong University from April to October 2007.SD rats were provided by B&K Universal Group Limited.The experimental procedure was consistent with animal ethical standard.The MSCs from male SD rat femurs and tibia were isolated by density gradient centrifugation.The third passage of MSCs after chemical-induction and stress-induction was labeled with DAPI before transplantation.Thirty-six 8-week-old SD rats were randomly divided into control group and experimental group(n=18).The animal model of denervated gastrocnemius muscles were made by cutting the left sciatic nerve and creating nerve defect about 1 cm. MSCs were percutaneously transplanted to medial and lateral gastrocnemius of the experimental group rats,while low carbohydrates DMEM culture solution without MSCs and fetal bovine serum were transplanted to gastrocnemius of the control group.Bilateral gastrocnemius muscles of each rat from the two groups were weighed 4,8 and 12 weeks postoperatively after examining the motor unit potential and fibrillation potential.The gastrocnemius muscles underwent HE staining and image analysis to measure cross-section area of muscle fiber.The amount of protein was detected by BCA method. RESULTS:Muscular atrophy was observed 2 weeks after denervation.The motor unit waveshape of gastrocnemius became single; time limit became long;voltage became low,and the fibrillation potential norientation wave was increased.Differences were observed between two groups 4 weeks and 8 weeks,but no differences were observed after 12 weeks.Cells with fluorescence were observed in transplantation sites of the experimental group,but not in the control group.The wet weight remnant rate,cross-sectional area of fiber remnant rate and muscle amount protein content remnant rate in rates transplanted with MSCs were significantly lower than those in the control group 4 and 8 weeks after surgery(P