The role of Q10 engineering mesenchymal stem cell-derived exosomes in inhibiting ferroptosis for diabetic wound healing

Background: Ferroptosis plays an essential role in the development of diabetes and its complications, suggesting its potential as a therapeutic target. Stem cell-derived extracellular vesicles (EVs) are increasingly being developed as nano-scale drug carriers. The aim of this study was to determine the role of ferroptosis in the pathogenesis of diabetic wound healing and evaluate the therapeutic effects of coenzyme Q10 (Q10)- stimulated exosmes derived from mesenchymal stem cells (MSCs). Methods: Human keratinocytes (HaCaTs) were exposed to high glucose (HG) conditions in vitro to mimic diabetic conditions, and the ferroptosis markers and expression level of acyl-coenzyme A synthase long-chain family member 4 (ACSL4) were determined. Exosomes were isolated from control and Q10-primed umbilical cord mesenchymal stem cells (huMSCs) and characterized by tramsmission electron microscopy and immunofluorescence staining. The HG-treated HaCaTs were cultured in the presence of exosomes derived from Q10-treated huMSCs (Q10Exo) and their in vitro migratory capacity was analyzed. Results: Q10-Exo significantly improved keratinocyte viability and inhibited ferroptosis in vitro. miR-548ai and miR-660 were upregulated in the Q10-Exo and taken up by HaCaT cells. Furthermore, miR-548ai and miR-660 mimics downregulated ACSL4-inhibited ferroptosis in the HG-treated HaCaT cells and enhanced their proliferation and migration. However, simultaneous upregulation of ACSL4 reversed their effects. Q10-Exo also accelerated diabetic wound healing in a mouse model by inhibiting ACSL4-induced ferroptosis. Conclusions: Q10-Exo promoted the proliferation and migration of keratinocytes and inhibited ferroptosis under hyperglycemic conditions by delivering miR-548ai and miR-660. Q10-Exo also enhanced cutaneous wound healing in diabetic mice by repressing ACSL4-mediated ferroptosis. [GRAPHICS]