Astragalus and human mesenchymal stem cells promote wound healing by mediating immunomodulatory effects through paracrine signaling

Background: Skin regeneration from an injury without a scar is still a challenge. Methods: A murine model of a skin wound was treated with a combination of extract of astragalus and exosomes of mesenchymal stem cells (MSCs). CD11b+ and CD45 macrophages were detected and levels of cytokines were tested. Results: The expression of growth factors VEGF, FGF2 and EGF was elevated after treatment administered to MSCs. The administration of ethanolic extract of astragalus decreased the expression of TNF-α, IL-1β and IL-6 and simultaneously increased the levels of IL-10. The combination sped up the process of wound healing. A sustained-release gel with both ingredients was developed to enhance restoration from granulation. Conclusion: The extract of astragalus promotes the efficacy of MSC-derived exosomes in skin repair.