Insulin-Induced Gene 1-Enhance Secretion of BMSC Exosome Enriched in miR-132–3p Promoting Wound Healing in Diabetic Mice

Abstract

Chronic diabetic wounds represent a significant clinical challenge because of impaired healing processes, which require innovative therapeutic strategies. This study explores the therapeutic efficacy of insulin-induced gene 1-induced bone marrow mesenchymal stem cell exosomes (Insig1-exos) in promoting wound healing in diabetic mice. We demonstrated that Insig1 enhanced the secretion of bone marrow mesenchymal stem cell-derived exosomes, which are enriched with miR-132–3p. Through a series of in vitro and in vivo experiments, these exosomes significantly promoted the proliferation, migration, and angiogenesis of dermal fibroblasts under high-glucose conditions. They also regulated key wound-healing factors, including matrix metalloproteinase-9, platelet-derived growth factor, vascular endothelial growth factor, transforming growth factor-β1, and platelet endothelial cell adhesion molecule-1, thereby accelerating wound closure in diabetic mice. Histological analysis showed that Insig1-exos were more effective in promoting epithelialization, enhancing collagen deposition, and reducing inflammation. Additionally, inhibition of miR-132–3p notably diminished these therapeutic effects, underscoring its pivotal role in the wound-healing mechanism facilitated by Insig1-exos. This study elucidates the molecular mechanisms through which Insig1-exos promotes diabetic wound healing, highlighting miR-132–3p as a key mediator. These findings provide new strategies and theoretical foundations for treating diabetes-related skin injuries.