Green propolis extract for the treatment of alkali-induced superficial corneal ulcers: local and systemic analyses

Abstract Green propolis, produced by honeybees from the resin of certain plants, has garnered attention for its potential health benefits. Green propolis contains compounds like artepillin C, which exhibits antioxidant, anti-inflammatory, and antimicrobial properties. This study's objective was to examine the effects of green propolis extract containing 21.05% artepillin C, topically administered (5, 10 and 15 mg/mL) in rats with induced superficial corneal ulcers with alkali, applied four times daily, for 96 hours. Rats treated with the green propolis extract exhibited of ulcer reduction more significant reduction after 24 hours of treatment than untreated animals, suggesting a similar healing activity of the commercial drug. After 96 hours of treatment, the rats were euthanized, and the corneas were submitted for histopathological analysis; no statistical difference was detected between rats treated with green propolis and those not treated in terms of polymorphonuclear and neovessel counts in the corneal stroma. In the toxicogenetic analysis, by the micronucleus test, no significant differences were observed in the frequencies of chromosomal damage and the ratio of polychromatic erythrocytes to the total number of erythrocytes between treated and untreated animals, revealing the absence of genotoxicity and cytotoxicity, respectively. The biochemical results did not indicate a hepatotoxic or nephrotoxic effect of the formulations containing green propolis. Like this, the standardized green propolis extract induced corneal epithelialization without toxic effects, rendering it a promising option for treating superficial keratitis.