Exosomes derived from fibroblasts in DFUs delay wound healing by delivering miR-93-5p to target macrophage ATG16L1.

Diabetes is an extremely costly disease, one-third of which are attributed to the management of diabetic foot disease including chronic, non-healing, diabetic foot ulcers (DFUs). Therefore, much effort is needed to understand the pathogenesis of DFUs and novel therapeutics. We utilized exosome staining to confirm the interaction between fibroblast-derived exosomes and macrophages. Subsequently, we employed public data and qPCR to screen for upregulated miRNAs in fibroblast-derived exosomes in DFUs. The relationship between was validate miR-93-5 and ATG16L1 through data prediction and dual-luciferase reporter assays. A variety of molecular biology experiments were used for subsequent pathway validation. Additionally, we established Atg16l1MKI and Nlrp3MKO mice for further validation. We identified that miR-93-5p derived from fibroblasts played an important role in M1 macrophages polarization. Predicted by database, we found that miR-93-5p can bind to ATG16L1 mRNA, thereby influencing macrophage autophagy mediated by ATG16L1 in the clearance of ROS, thus activating the NLRP3 signaling pathway. In vivo, miR-93-5p antagomir treatment accelerated diabetic wound healing and induced M2 macrophage polarization. Fibroblasts and macrophages show cell crosstalk during the development of DFUs by miR-93-5p, and that antagomir treatment may be a promising and technically advantageous alternative to DFUs therapies.