Co-trasplantation of Pancreatic Islets with Mesenchymal Stem Cells promotes the functional recovery of diabetic neuropathy in vivo

Treatment of type-1diabetes with pancreatic islet transplantation is an intriguing therapeutic option, aimed to replace insulin administration, but very limited in clinical practice, mainly for the great number of islets necessary and for their short survival. Aim of this work is to verify the ability of Mesenchymal Stem Cells (MSCs) co-transplanted with Pancreatic Islets to improve the feasibility of this approach, by acting both on glycaemic control and on long term disease complications, such as the diabetic neuropathy. 5 groups were used (8 rats/group): a) healthy controls; b) Streptozotocin-induced diabetic rats; c) Diabetic rats transplanted with pancreatic islets (3000); d) Diabetic rats co-transplanted with pancreatic islets (2000) and MSCs (106); Diabetic rats treated with MSCs (106). Transplantations were performed after the assessment of neuropathic signs, such as the decrease of Nerve Conduction Velocity (NCV) and the impairment of nociceptive (thermal and mechanical) thresholds. The same parameters were evaluated two months after the transplantation. Diabetic rats transplanted only with pancreatic islets, or co-transplanted with MSCs and a suboptimal number of pancreatic islets, showed a marked and significant glycaemia value reduction, an improvement of thermal and mechanical sensitivity, and a nearly complete restoration of NCV with respect to diabetic-untreated rats. No differences were observed between diabetic rats and diabetic rats treated with only MSCs. Co-transplantation of MSCs with Pancreatic Islets allows to reduce the successful number of pancreatic islets, to obtain a better and more physiologic glycaemic control, and to induce the regression of painful neuropathy signs, thus ameliorating diabetes complications management