Abstract
Diabetic wounds, as a kind of refractory wound, are very difficult to heal. Both endothelial progenitor cell (EPC) transplantation and platelet-rich plasma (PRP) can improve diabetic wound healing to some extent. However, PRP application cannot provide reparative cells, while EPC transplantation cannot replenish the required growth factors for wound healing. Thus, when applied alone, neither of these factors is sufficient for effective wound healing. Furthermore, the proliferation, differentiation, and fate of the transplanted EPCs are not well known. Therefore, in this study, we examined the efficacy of combined PRP application with EPC transplantation in diabetic wound healing. Our results indicated that PRP application improved EPC proliferation and migration. The Notch signaling pathway plays a key role in the regulation of the proliferation and differentiation of stem cells and angiogenesis in wound healing. The application of PRP upregulated the Notch pathway-related gene and protein expression in EPCs. Furthermore, experiments with shNotch1-transfected EPCs indicated that PRP enhanced the function of EPCs by upregulating the Notch1 signaling pathway. In vivo studies further indicated that the combination of PRP and EPC transplantation increased neovascularization, reduced wound size, and improved healing in rat wound models. Thus, PRP application can provide the necessary growth factors for wound healing, while EPC transplantation offers the required cells, indicating that the combination of both is a potent novel approach for treating diabetic wounds.