Overexpression of IL-10 in Adipose Mesenchymal Stem Cells Promotes Wound Healing in Diabetic Mice.

Diabetic ulcers are serious chronic wounds that are challenging to heal and can lead to amputation or even death. This study aims to utilize interleukin-10 (IL-10) overexpressing adipose mesenchymal stem cells to investigate their potential in promoting the healing of diabetic ulcers and to explore their mechanism of action. The analysis of stem cell characteristics of ADSC-IL10 was performed through flow cytometry, cell scratch assay, MTT assay, and adipogenic and osteogenic differentiation assays. The detection of the M1 and M2 phenotypes of mouse peritoneal macrophages (RAW 264.7) under conditioned medium stimulation was carried out using qPCR technology. The assessment of the effects of conditioned media from ADSCs overexpressing IL-10 (ADSC-IL10 CM) and conditioned media from adipose-derived stem cells (ADSC CM) on the migration of normal skin fibroblasts and human immortalized epidermal cells was done using Transwell and cell scratch methods. A diabetic mouse model was induced using a high-fat/high-sugar diet plus streptozotocin (STZ) to detect the number of M2 macrophages and the expression levels of inflammatory factors (IL-1β, IL-6, IL-10, and MCP-1) and growth factors (EGF, VEGF, and TGFβ-1) in mouse skin tissue. The overexpression of IL-10 did not change the biological properties of ADSCs. In diabetic mice, the transplantation of IL-10 overexpressing ADSCs for wound healing was more effective than the transplantation of ADSCs alone. ADSCs overexpressing IL-10 promoted the expression of M2 macrophages marker; inhibited the secretion of proinflammatory factors such as IL-1β, IL-6, and MCP-1; and enhanced the production of growth factors including EGF, TGFβ-1, and VEGF. Furthermore, it facilitated the migration of skin fibroblasts and epidermal cells from diabetic mice to the wound site. ADSCs that overexpress IL-10 promote wound healing in diabetic mice by reducing inflammatory responses, enhancing growth factor secretion, and increasing the migration of fibroblasts and epidermal cells.