Wounds and burn injury are major causes of death and disability worldwide. Myricetin is a common bioactive flavonoid isolated naturally from the plant kingdom. Herein, a topical application of naturally isolated myricetin from the shoots of Tecomaria capensis v. aurea on excisional wound healing that was performed in albino rats. The wounded rats were treated every day with 10 and 20% myricetin for 14 days. During the experiment, the wound closure percentage was estimated at days 0, 7, and 14. Effects of myricetin on the inflammatory cytokines (tumor necrosis factor-α (TNF-α), interleukin-1β (IL-1β), and cluster of differentiation 68 (CD68) in the serum were evaluated using immunosorbent assay kits. The percentage of wound closure and contraction was delayed in wounded rats (67.35%) and was remarkably increased after treatment of wounded rats with myricetin; the treatment with 20% myricetin was the most potent (98.76%). Histological findings exhibited that 10% myricetin caused the formation of a large area of scarring at the wound enclosure and stratified squamous epithelium without the formation of papillae as in the control group. Treatment with 20% myricetin exhibited less area of scarring at the wound enclosure as well as re-epithelialization with a high density of fibroblasts and blood capillaries in the wound. Level elevations of serum pro-inflammatory cytokines, IL-1β, and TNF-α and macrophage CD68 were decreased in wounded rats treated with myricetin. Thus, it can be suggested that the enhancements in inflammatory cytokines as well as systemic reorganization after myricetin treatment may be recommended to play a crucial part in the promotion of wound healing. The findings suggest that treatment with a higher dose of myricetin was better in improving wound curing in rats. It could serve as a potent anti-inflammatory agent and can be used as an adjunctive or alternative agent in the future.
Keywords: Tecomaria capensis v. aurea; flavonoids; inflammatory cytokines; myricetin; wound healing.