Exosomes derived from adipose stem cells in combination with hyaluronic acid promote diabetic wound healing

Diabetic wound is one of the main challenges in dermatology. Although stem cell-based treatment has therapeutic benefits in wound repair, the clinical application is still limited. Herein we investigated whether adipose stem cells -derived exosomes (Exo) loaded on hyaluronic acid (HA) could promote healing in diabetic rats. Sixty diabetic rats were randomly planned into the control group, Exo group, HA group, and HA+Exo group. On days 7, 14, and 21, five rats from each group were sampled for stereological, molecular, and tensiometrical assessments. Our results indicated that the wound closure rate, the total volumes of new epidermis and dermis, the numerical densities of fibroblasts, the length density blood vessels, collagen density as well as tensiometrical parameters of the healed wounds were significantly higher in the treated groups than in the control group, and these changes were more obvious in the HA+Exo ones. Furthermore, the expression of TGF-beta and VEGF genes were meaningfully upregulated in all treated groups compared to the control group and were greater in the HA+Exo group. This is while expression of TNF-alpha and IL-1 beta, as well as numerical densities of neutrophils decreased more considerably in the HA+Exo group in comparison to the other groups. Generally, it was found that using both HA injection and exosomes has more effect on diabetic wound healing.