Ononin-modified Chitosan/β-glycerophosphate hydrogel-loaded adipose-derived stem cells promote the repair of diabetic wounds in rats

To evaluate the mechanistic synergy of an ononin-modified chitosan/β-glycerophosphate (CS/β-GP) hydrogel loaded with adipose-derived stem cells (ADSCs) in repairing diabetic wounds (DWs). We specifically aimed to determine if ononin could biochemically remodel the hostile diabetic microenvironment to enhance ADSCs survival and potency. Primary rat ADSCs were characterized by flow cytometry. A thermosensitive CS/β-GP hydrogel was fabricated, and its microstructure was characterized by scanning electron microscopy (SEM). he biological response of ADSCs to ononin was assessed via CCK-8, scratch assays and Live/Dead staining to identify the optimal concentration. A diabetic wound model in rats was established, with all rats randomly assigned into five groups: Control, model, ononin (On), ADSCs, and ononin+ADSCs (On+ADSCs). Wound healing rates were recorded at days 0, 4, 8, and 12 post-treatment. At 12th day, the synergistic impact of ononin and ADSCs on the wound microenvironment was evaluated by measuring healing rates, inflammatory cytokines (TNF-α, IL-1β, IL-6). Additionally, the cumulative release profiles of IGF-1, VEGF, and TGF-β3 from the hydrogel-loaded ADSCs were monitored over 96 h, fitting a Korsmeyer-Peppas kinetic model to characterize the sustained release behavior. Histopathological evaluation, immunohistochemistry for CD31, collagen I, and α-SMA, and Western blot analysis for VEGF, VEGFR2, and CD31 were performed for mechanistic exploration. SEM confirmed a three-dimensional interconnected porous microstructure of the CS/β-GP hydrogel, providing a biomimetic scaffold for cell retention. 20µM ononin significantly promoted ADSCs proliferation and migration without observable cytotoxicity (P < 0.05). The Ononin release profile from the hydrogel followed a sustained release pattern, in accordance with the Korsmeyer-Peppas model. The hydrogel demonstrated sustained release of both Ononin and ADSCs-derived growth factors. Notably, ononin acted as a biochemical modifier that enhanced the paracrine activity of ADSCs. Compared with the model group, the On+ADSCs group exhibited the most significant acceleration in wound closure, re-epithelialization, and collagen deposition. This was accompanied by a robust suppression of inflammatory cytokines and a marked upregulation of CD31, collagen I, and α-SMA. Mechanistically, the combination therapy potently activated the VEGF/VEGFR2 signaling axis, significantly outperforming monotherapies (P < 0.05). Ononin-modified CS/β-GP hydrogel effectively promotes diabetic wound healing by optimizing the inflammatory microenvironment and amplifying ADSCs-mediated angiogenesis through the VEGF/VEGFR2 axis. This composite biomaterial represents a promising strategy for chronic wound management.