MG53 binding to CAV3 facilitates activation of eNOS/NO signaling pathway to enhance the therapeutic benefits of bone marrow-derived mesenchymal stem cells in diabetic wound healing

Impaired wound healing in diabetes results from a complex interplay of factors that disrupt epithelialization and wound closure. MG53, a tripartite motif (TRIM) family protein, plays a key role in repairing cell membrane damage and facilitating tissue regeneration. In this study, bone marrow-derived mesenchymal stem cells (BMSCs) were transduced with lentiviral vectors overexpressing MG53 to investigate their efficacy in diabetic wound healing. Using a db/db mouse wound model, we observed that BMSCs-MG53 significantly enhanced diabetic wound healing. This improvement was associated with marked increase in re-epithelialization and vascularization. BMSCs-MG53 promoted recruitment and survival of BMSCs, as evidenced by an increase in MG53/Ki67-positive BMSCs and their improved response to scratch wounding. The combination therapy also promoted angiogenesis in diabetic wound tissues by upregulating the expression of angiogenic growth factors. MG53 overexpression accelerated the differentiation of BMSCs into endothelial cells, manifested as the formation of mature vascular network structure and a remarkable increase in DiI-Ac-LDL uptake. Our mechanistic investigation revealed that MG53 binds to caveolin-3 (CAV3) and subsequently increases phosphorylation of eNOS, thereby activating eNOS/NO signaling. Notably, CAV3 knockdown reversed the promoting effects of MG53 on BMSCs endothelial differentiation. Overall, our findings support the notion that MG53 binds to CAV3, activates eNOS/NO signaling pathway, and accelerates the therapeutic effect of BMSCs in the context of diabetic wound healing. These insights hold promise for the development of innovative strategies for treating diabetic-related impairments in wound healing.