The Impact Of Bone Marrow Mesenchymal Stem Cells And Insulin Producin Cells Derived From Them Transplantation On Recipient Islets Proliferation And Neovascularization

Diabetes mellitus is a common endocrine and metabolic disease. Taking oral drugs and exogenous insulin, both are effective therapies for diabetes mellitus, but they neither can mimic physiological insulin secretion and nor prevent the chronic complications caused by high glucose level. Pancreas transplantation or islets transplantaion can reverse diabetes, but the former is a complicated operations with high risk. To contrast,islets transplantaiton is a simple and effective procedure. Whereas, donor deficiency and immunological rejection is hampering isltet tranasplantation's evolution nowadays.Islets isolated from animals and derived from stem cells is a hot research field on life science. Some research results have suggested donor deficiency can be resolved to some degree. Islet xenoplantaton has much more intensive immune rejection than allogenic transplantation, so that they haven't been used generally. Islets derived from stem cells transplantation have been practiced only in the laboratory becaused of their low insulin secretion capacity and immunological rejection. Bone marrow mesenchmymal stem cells(MSCs), one kind of adult stem cells, which ared located in many tissues. MSCs can be harvested easily and induced into insulin producing cells( IPCs)either vivo or vitro. Transplantation of MSCs or IPCs can decrease recipients'glucose level, scinentists consider them as new ideal insulin resource and pay more attention about them. The latest research suggested that istlets regeneration need the help of vascular endothelial cell(s VECs), which was caused by vascular endothelial cells proliferation around islets after cells transplantation.Objective:Rat MSCs will be induced into IPCs in vitro, then they can be transplanted in the diabtes recipients'renal capsule. The regeneration of the recipients'islets and VECs around them can be observed in the microscope by immunohistochemistry after the cells tranplantation. All these research results can suggest one of reasons of decreasing glucose level and prolonging survival time for recipient rats, and illuminate the impact for remnant islets and periislets vascular endothelial cells proliferation by MSCs or IPCs transplantation.The impact of MSCs or IPCs transplantation on recipient islets proliferation and neovascularization:Rat MSCs were isolated and cultured in vitro, then passaged 3 MSCs can be induced into IPCs. The diabetic rats were induced by peritoneal streptozocin injection(60mg/Kg). MSCs and IPCs were transplanted in the recipients'right kidney capsule. The glucose level and weight were monited after transplantation. Hyperglycaemia decreased and animal survival time prolonged. When the glucose concentration was 10mmol/L, all groups'right kidney and pancrease were removed simultaneously and observed by immunohistochemistry with CD31,insulin and PCNA. Results:The recipient's remnaining islets and the periislets vascular endothelial cells suggested proliferative, and CD31+ and Insulin+ cells in the MSCs groups were observed in the right kidney. Conclusions:MSCs and IPCs transplantation can promote the recipients'islets and periislets vascular endothelial cells proliferation, and MSCs differentiated into IPCs and in vivo. In general, rat MSCs can differentiate into IPCs under suitable conditon when pancreatic extract was added intot the culture meduim. When MSCs and IPCs were transplanted into the recipient diabete rats, the animal glucose level and survival time prolonged. It was shown that MSCs or IPCs transplantation improved the recipient remaining islets and periislets vascular endothelial cells regeneration by immunohistochemistry, which to some degree illuminate the mechanism of decreasing the recipients'glucose level and provided the theoretical basis for curing diabete mellitus by MSCs transplantation.