Human bone marrow mesenchymal stem cells-derived exosomes stimulate cutaneous wound healing mediates through TGF-β/Smad signaling pathway
Abstract Background: Cutaneous wound healing represents a morphogenetic response to injury, and is designed to restore anatomic and physiological function. Human bone marrow mesenchymal stem cells-derived exosomes (hBM-MSCs-Ex) is a promising source for cell-free therapy and skin regeneration. Methods: In this study, we investigated the cell regeneration effects and its underlying mechanism of hBM-MSCs-Ex on cutaneous wound healing in rats. In vitro studies, we evaluated the role of hBM-MSCs-Ex in the two types of skin cells: human keratinocytes (HaCaT) and human dermal fibroblasts (HDFs) for the proliferation. For in vivo studies, we used a full-thickness skin wound model to evaluate the effects of hBM-MSCs-Ex on cutaneous wound healing in vivo. Results: The results demonstrated that hBM-MSCs-Ex promote both two types of skin cells growth effectively and accelerate the cutaneous wound healing. Interestingly, we found that hBM-MSCs-Ex significantly down-regulated TGF-β1, Smad2, Smad3, and Smad4 expression, while up-regulated TGF-β3 and Smad7 expression in the TGF-β/Smad signaling pathway. Conclusions: Our findings indicated that hBM-MSCs-Ex effectively promote the cutaneous wound healing through inhibiting the TGF-β/Smad signal pathway. The current results providing a new sight for the therapeutic strategy for the treatment of cutaneous wounds.