Abstract
BACKGROUND: Diabetic wounds remain difficult to treat due to persistent oxidative stress, chronic inflammation, and vascular dysfunction. These factors reinforce each other, forming a vicious cycle that leads to delayed healing, poor angiogenesis, and high amputation risk. Existing therapies often fail because they are unable to address these challenges simultaneously. Therefore, this study aimed to develop a hybrid extracellular vesicle system that targets these multiple barriers concurrently to promote diabetic wound healing. METHODS: A biohybrid nanovesicle system (DFO@HEVs) was built by fusing endothelial cell-derived extracellular vesicles with neutrophil-derived nanovesicles (forming hybrid extracellular vesicles, HEVs), which were loaded with deferoxamine (DFO). The vesicles were tested for their physicochemical properties, drug loading, and safety. Therapeutic effects were studied in vitro using HG/PA-stimulated endothelial cells and macrophages and in vivo in diabetic mouse wounds. The analyses included microscopy, flow cytometry, histology, transcriptomics, and database-based single-cell RNA sequencing. RESULTS: DFO@HEVs showed dual targeting: homing to endothelial cells via CXCR4 and to inflamed sites via β2 integrin. They enhanced endothelial uptake, promoted angiogenesis through PI3K/AKT/HIF-1α and VEGF signaling pathways, and reduced oxidative stress and ferroptosis by activating Nrf2 and upregulating antioxidant genes. They also shifted macrophages toward an anti-inflammatory M2 phenotype, boosted efferocytosis, and suppressed NF-κB/NLRP3-driven inflammation. In diabetic mice, treatment with DFO@HEVs accelerated wound closure, re-epithelialization, collagen deposition, and new vessel formation, while lowering neutrophil infiltration, reactive oxygen species levels, ferroptosis, and pro-inflammatory cytokines, creating a healing-supportive environment. CONCLUSIONS: DFO@HEVs provided a hybrid nanovesicle system for combined membrane and drug delivery. By promoting angiogenesis, limiting ferroptosis, and resolving inflammation, they disrupted the cycle that prevented diabetic wound repair. This approach shows a strong potential as a new treatment for chronic wounds.