An experimental study on treatment of diabetic rats through transplantation of allogeneic bone marrow mesenchymal stem cells

Objective:To observe the curative effectiveness of allogeneic bone marrow mesenchymal stem cells(BMSC) transplantation in diabetic rats and the possible mechanism.Methods:BMSC were isolated from allogeneic bone marrow of SD rat by adhesive screening method and cultured in vitro.The second passage of BMSC was transfected with Ad-GFP.BMSC that stably expressed GFP were obtained before transplantation.Streptozotocin-induced diabetic rats(plasma glucose≥16.7 mmol/L) were divided at random into untreated group(UTG) and BMSC transplantation group(TPG).BMSC were transplanted into allogeneic diabetic rats of TPG through vena caudalis(0.4 ml,1×106-1×107/ml).Another 5 normal rats picked out at random(normal control group) and the diabetic rats of UTG were injected via tail vein with the same quantity of physiological saline.After the 2 weeks transplantation,the levels of plasma glucose,HbA1c and insulin were determined.The pancreas was dissected out for pathological sections.Insulin reaction with immunohistochemistry of rats was observed.Fluorescent microscopy was used to observe the expression of GFP labeled cells in the pancreas.Results:The result showed that levels of plasma glucose and HbA1c were higher obviously in UTG than in normal control group(NCG),and insulin level lower(P0.001).The levels of plasma glucose and HbA1c were lower obviously in TPG than in UTG(P0.05),and insulin level higher(P0.05).The numbers of beta-cells of the UTG decreased and the insulin reaction showed negative results.The numbers of beta-cells of the TPG increased and the insulin reaction showed positive and strong positive results.The cells of GFP were observed in the excrine tissues of pancreas,but not observed in the islet.Conclusion:It is concluded that BMSC transplantation by tail vein injection could engraft into pancreas tissues of diabetic rats,depress the levels of plasma glucose and HbA1c,accelerate the synthesis of the insulin.BMSC transplantation might promote endogenous regeneration of islets in diabetic rats.