Sodium alginate/gelatin hydrogels loaded with adipose-derived mesenchymal stem cells promote wound healing in diabetic rats.

Background: Chronic refractory wounds are a common complication in diabetic patients. Adipose-derived mesenchymal stem cells (ASCs) have been shown to play an essential role in diabetic wound repair.

Aims: To determine whether a composite of ASCs and sodium alginate/gelatin (Gel-Al) hydrogel can promote diabetic wound healing.

Methods: Full-thickness cutaneous wounds were created in streptozotocin-induced diabetic rats prior to treatment with Gel-Al hydrogels loaded with ASCs. Hydrogel biocompatibility and wound healing were analyzed. Hematoxylin and eosin staining, Masson staining, immunofluorescence, enzyme-linked immunosorbent assays (ELISA), and quantitative real-time PCR were performed for the assessment of cellular responses.

Results: Compared to the control group or Gel-Al alone group, the combination of Gel-Al and ASCs promoted wound closure, facilitated granulation tissue regeneration and collagen deposition, and upregulated the expression of vascular endothelial growth factor (VEGF), platelet-derived growth factor (PDGF), epidermal growth factor (EGF), and endothelial cell marker CD31. Moreover, the combination of Gel-Al and ASCs decreased interleukin-6 (IL-6) and interleukin-1β (IL-1β) expression, increased transforming growth factor beta1 (TGFβ1), interleukin-10 (IL-10), interleukin-4 (IL-4) and interleukin-13 (IL-13) expression, and increased M2 macrophage polarization.

Conclusions: Gel-Al hydrogels loaded with ASCs accelerate diabetic wound healing. The Gel-Al hydrogel-based ASC system therefore represents an innovative therapeutic strategy for diabetic wound repair.