Comparative study of the effects of subcutaneously administered umbilical cord-derived mesenchymal stem cells and exosomes derivatives on wound healing in a chemical burn model of alkaline-induced skin burns.

BACKGROUND In burn-injured skin, the main goal is to accelerate wound healing and restore the barrier. In chemical burns, excessive inflammation and deep tissue damage complicate repair. Regenerative medicine approaches may modulate these processes. This study investigated the effects of human umbilical cord-derived mesenchymal stem cells (HucMSCs) and their exosomes (Exo-HucMSCs) on wound healing in a chemical burn model. METHODS A chemical burn was induced on the dorsal skin of 24 Wistar rats using 2 M sodium hydroxide. Rats were randomly assigned to three groups (n = 8): HucMSC-treated, Exo-HucMSC-treated and control. Wound closure and histopathological changes were evaluated and compared among groups. RESULTS Wound closure was higher in the HucMSC group (78.15% ± 9.19) than in the Exo-HucMSC (66.11% ± 7.33) and control groups (57.35% ± 4.54) (p < 0.05). Histologically, treatment groups showed early inflammatory changes on days 1 and 3 (p < 0.01), enhanced striated muscle regeneration on day 7 (p < 0.01) and narrower non-epithelialized areas on day 21 (p < 0.05). Neoangiogenesis was greater in the Exo-HucMSC group on day 3 (p < 0.01). CONCLUSION Both HucMSC and Exo-HucMSC treatment accelerated chemical burn healing. Exosomes promoted early-phase angiogenesis, whereas HucMSCs provided superior long-term wound closure.