Enhanced wound healing in diabetic rats using Boswellia serrata Roxb.- Zn gel: a multifunctional approach targeting...

Diabetic wounds present a major clinical challenge due to impaired angiogenesis, chronic inflammation, and oxidative stress. This study evaluated the wound healing efficacy of a novel Boswellia serrata Roxb. extract-Zinc (BSF-Zn) gel formulation in diabetic rats, integrating phytochemical profiling, antimicrobial assays, and in vivo healing metrics. Time-kill assays revealed potent bactericidal activity against Staphylococcus aureus and Escherichia coli, with ≥ 3 log₁₀ CFU/mL reduction within 12 h. In diabetic excision wound models, BSP + Zn hydrogel markedly accelerated healing, reducing wound area from 98 to 11.3 mm² (93.1%) by day 21, compared to 42 mm² (72.7%) in diabetic control group. Healing effects of BSP + Zn were slightly better than BSP alone (15 mm², 89.6%), standard gel (13.5 mm², 91.8%) indicating superior contraction, and faster closure. Topical gel application on the wound significantly reduced the levels of interleukin (IL)-1β, IL-6, tumor necrosis factor alpha (TNF-α), and matrix metalloproteinase-9 (MMP-9) in scraped wound skin on day 7 compared to diabetic controls. These pro-inflammatory cytokines were reduced as the wound healed by day 21, and levels were lower in the treatment group than in the diabetic group. BSF and BSF-Zn gel increased the level of superoxide dismutase, catalase, and glutathione, and increased malondialdehyde as compared to diabetic rats, indicating lowering of oxidative stress and lipid peroxidation in wound regions. Structural and vascular recovery was evidenced by increased collagen-I (along with a simultaneous decrease in collagen III) and vascular endothelial growth factor (VEGF) expression, while histological analysis confirmed re-epithelialization and regeneration of dermal appendages. These findings highlight BSF alone and with Zinc as promising agents to boost antimicrobial defence, regulate inflammation, restore oxidative balance, and enhance tissue regeneration, thereby accelerating wound healing in diabetic rats.