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bioRxiv · 10.64898/2026.01.28.702240

Evaluation of the Anti-Inflammatory and Wound-Healing Potentials of Nigella sativa Extract in Dermal Injury Models

Sowunmi, K. S.·Ibrahim, M. O.
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Abstract

Skin repair depends on balanced inflammation, oxidative control, and growth-factor signalling. Disruption of these events delays healing and leads to chronic wounds. Nigella sativa (black seed) contains bioactive compounds such as thymoquinone with anti-inflammatory and antioxidant activity, but its integrated effect on dermal repair remains unclear. This study evaluated the anti-inflammatory and wound-healing properties of N. sativa extract in a full-thickness excision wound model in rats. Animals were divided into control, standard (1% silver sulfadiazine), and N. sativa ointment-treated (10% w/w) groups. Wound contraction, histological organisation, antioxidant enzymes, inflammatory cytokines, and expression of pro-repair genes were assessed. Topical N. sativa significantly accelerated wound closure (97.5 {+/-} 1.2 % vs. 84.7 {+/-} 2.1 % in controls, p < 0.001) and improved epithelial regeneration and collagen deposition. Treatment enhanced superoxide dismutase and catalase activities by over 35%, reduced malondialdehyde by 38%, and lowered TNF-, IL-1{beta}, and IL-6 levels by 33-46%. VEGF and PDGF gene expression increased 2.7- and 2.2-fold, respectively, compared with untreated wounds. These results demonstrate that N. sativa extract promotes healing through concurrent modulation of inflammation, oxidative balance, and angiogenic signalling. The findings support its potential as a natural, biocompatible therapeutic for managing dermal injuries and cosmetic skin repair. Further work should optimise formulation, dosage, and clinical application to translate these benefits to human wound management.

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Sowunmi, K. S., Ibrahim, M. O.. 2026-01-29. Evaluation of the Anti-Inflammatory and Wound-Healing Potentials of Nigella sativa Extract in Dermal Injury Models. https://doi.org/10.64898/2026.01.28.702240

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