Efficacy of early systemic betamethasone or cyclosporin A after corneal alkali injury via inflammatory cytokine reduction

Purpose: To evaluate the effects of early systemic administration of betamethasone or cyclosporin A (CsA) on inflammatory cytokine expression and corneal damage after alkali injury. Methods: Sixty-five Wistar rat corneas injured with 1N NaOH were divided into three groups: untreated, betamethasone-treated and CsA-treated. Both agents were administered systemically and daily during the first 7 days after injury. Interleukin (IL)-1alpha, -6 and -8 concentrations in the injured corneas were measured with ELISA at 2, 4 and 7 days after injury. Corneal damage was evaluated by scoring clinical findings. Results: In untreated injured corneas, IL-1alpha, -6 and -8 were markedly elevated during the 7-day period following injury. Both betamethasone and CsA significantly suppressed IL-1alpha and IL-8 at day 4. Only betamethasone significantly suppressed IL-6 at days 4 and 7. Both agents significantly reduced corneal opacity at day 4. Conclusion: Early systemic administration of betamethasone or CsA after alkali injury may be of benefit by suppressing inflammatory cytokine expression in the cornea.