Gentiopicroside-loaded GelMA hydrogel promotes early diabetic wound repair by alleviating oxidative stress and is associated with attenuation of TLR4/NF-κB/NLRP3-related inflammatory activation.

Diabetic wounds remain difficult to heal because persistent inflammation, oxidative stress, impaired endothelial migration, defective angiogenesis, and disordered extracellular matrix remodeling jointly delay tissue repair. In this study, a gentiopicroside-loaded gelatin methacryloyl hydrogel (GelMA+Gent) was developed as a local therapeutic platform for diabetic wound repair. Concentration-screening experiments showed that Gent at 1-20 μM exhibited favorable cytocompatibility and partially restored cell viability under high-glucose stress. Under high-glucose conditions, GelMA + Gent most effectively improved HUVEC migration in scratch wound and Transwell assays. The GelMA + Gent hydrogel displayed an interconnected porous structure, favorable cytocompatibility, progressive biodegradation, and sustained Gent release. In a streptozotocin-induced diabetic rat wound model, GelMA + Gent promoted early wound closure compared with the Control, GelMA, and Gent groups during the 10-day observation period. Histological and immunofluorescence analyses showed reduced inflammatory infiltration, enhanced collagen deposition, increased CD31-positive endothelial structures, and enhanced perivascular α-SMA-positive coverage in GelMA + Gent-treated wounds. Biochemical analyses demonstrated that GelMA + Gent increased superoxide dismutase activity and decreased malondialdehyde accumulation, indicating improved redox balance. ELISA showed that GelMA + Gent increased TGF-β1 and VEGF levels while reducing IL-6, IL-1β, and TNF-α levels. Immunohistochemical staining further demonstrated reduced expression of NLRP3 inflammasome-associated proteins, including IL-1β, IL-18, GSDMD, Caspase-1, and NLRP3. Immunofluorescence analysis showed decreased TLR4, NF-κB p65, IL-6, and TNF-α-positive areas in GelMA + Gent-treated wounds. Overall, the data indicate that GelMA + Gent promotes early diabetic wound repair by improving endothelial migration, enhancing antioxidant defense and neovascularization, suppressing excessive inflammatory cytokine production, and attenuating TLR4/NF-κB/NLRP3-related inflammatory activation.