Plant-Derived Exosome-Like Nanovesicle-Loaded Hydrogels Promote Wound Healing

Healing of infected wounds is an intricate and dynamic physiological process that takes several days to complete. Momordica charantia-derived extracellular vesicles (MCEVs) have anti-inflammatory and antioxidant properties, and GelMA/HAMA dual-network injectable hydrogel loaded with MCEVs(MCEVs-GelMA/HAMA) may be a new strategy for accelerated wound healing. MCEVs were extracted by ultracentrifugation, and analyzed and identified by transmission electron microscopy (TEM), western blot and nanoparticle tracking analysis (NTA). The full-layer skin wound model of SD rat back was constructed, and MCEVs-GelMA/HAMA was injected into the subcutaneous tissue around the wound and observed and recorded continuously for 14 days. The wound healing rate was calculated by ImageJ image analysis software. On the 14th day after surgery, mouse skin pathological samples were collected for HE staining and immunohistochemical staining, and the number of neovascularization and the expression of vascular marker CD31 around the wound were analyzed. MCEVs were typical double-concave discs with diameters ranging from 50nm to 150nm. The wound healing rate of rats treated by MCEVs-GelMA/HAMA group was significantly better than that of control group. Gross skin samples and HE staining showed that the number of dermal neovasculars increased in the MCEVs-GelMA/HAMA treatment group. Immunohistochemical staining showed that the expression of vascular marker CD31 increased in the MCEVs-GelMA/HAMA treatment group. MCEVs-GelMA/HAMA can promote neovascularization and accelerate skin wound healing.