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Updated: Jan 14, 2026

Creation and Transplantation of an Adipose-derived Stem Cell ASC Sheet in a Diabetic Wound-healing Model
Published on: August 4, 2017
Engineered sEVs encapsulated in GelMA facilitated diabetic wound healing by promoting angiogenesis via targeting
Yan Cong1,2,3, Sheng Meng4, Xiaoye Xie1,2
1Department of Burns and Plastic Surgery, The Fourth Medical Center, Chinese PLA General Hospital, 51 Fucheng Road, Haidian District, Beijing 100048, China.
Background:
Chronic nonhealing wounds are major complications in diabetic patients, with impaired angiogenesis playing a critical role in the delayed healing process. Current treatments for diabetic wounds are inadequate. The dysregulation of endothelial cell genes, particularly thrombospondin-1 (TSP-1), impairs neovascularization and delays wound repair. In recent years, hydrogel-based wound dressings have gained widespread application in biomedicine. The study introduced a new therapeutic approach, embedding miR-221-3p-loaded small extracellular vesicles (miR-221OE-sEVs) within gelatin methacryloyl (GelMA) hydrogels to reduce TSP-1 levels and improve healing in diabetic wounds.
Methods:
First, we observed upregulated TSP-1 expression in human umbilical vein endothelial cells (HUVECs) when cultured in a high-glucose (HG) environment. We employed small interfering RNA (siRNA) and miR-221-3p to suppress TSP-1 expression and then evaluate the functional effects on HUVECs. Subsequently, miR-221-3p was encapsulated in sEVs via lentiviral transfection. The effects of miR-221OE-sEVs on HUVECs under HG conditions were evaluated. Finally, miR-221OE-sEVs were incorporated into a GelMA hydrogel (G-miR-221OE-sEVs) and applied to a diabetic murine wound model to evaluate their effects on wound closure and angiogenesis.
Results:
Under HG conditions, the use of siTSP-1 to silence TSP-1 enhanced the proliferation, migration, and tube formation capabilities of HUVECs. Similarly, miR-221-3p treatment exerted proregenerative effects via the targeting of TSP-1. We successfully generated miR-221OE-sEVs that exhibited a 28-fold increase in miR-221-3p expression, which significantly enhanced HUVEC functionality under HG conditions. Encapsulation within the GelMA hydrogel enabled G-miR-221OE-sEVs to significantly accelerate diabetic wound healing via increased angiogenesis.
Conclusions:
This study demonstrated the successful fabrication of a novel bioactive wound dressing (G-miR-221OE-sEVs), which promotes diabetic wound healing by promoting angiogenesis through the regulation of TSP-1. This approach offers a potential therapeutic option for enhancing the management of diabetic wounds.

