Exosomes derived from human adipose mesenchymal stem cells loaded bioengineered three-dimensional amniotic membrane-scaffold-accelerated diabetic wound healing.

The occurrence of wounds and defects in the healing process is one of the main challenges in diabetic patients. Herein, we investigated whether adipose-derived stem cells (ADSCs)-derived exosomes loaded bioengineered micro-porous three-dimensional amniotic membrane-scaffold (AMS) could promote healing in diabetic rats. Sixty diabetic rats were randomly allocated into the control group, exosome group, AMS group, and AMS + Exo group. On days 7, 14, and 21, five rats from each group were sampled for stereological, immunohistochemical, molecular, and tensiometrical assessments. Our results indicated that the wound closure rate, the total volumes of newly formed epidermis and dermis, the numerical densities of fibroblasts and proliferating cells, the length density blood vessels, collagen density as well as tensiometrical parameters of the healed wounds were considerably greater in the treated groups than in the control group, and these changes were more obvious in the AMS + Exo ones. Furthermore, the expression of TGF-β, bFGF, and VEGF genes was meaningfully upregulated in all treated groups compared to the control group and were greater in the AMS + Exo group. This is while expression of TNF-α and IL-1β, as well as cell numerical densities of neutrophils, M1 macrophages, and mast cells decreased more considerably in the AMS + Exo group in comparison with the other groups. Generally, it was found that using both AMS transplantation and ADSCs-derived exosomes has more effect on diabetic wound healing.