Observation on the efficacy of retinoic acid for alkali corneal burn in rats

Abstract

Objective To observe the efficacy of retinoic acid (RA) for the treatment of rats with corneal alkali burn. Methods The corneal alkali burn model of 36 Sprague-Dawley rats was established, all cases were randomly divided into RA group and control group, with 18 cases in each. RA group received RA eye drops and the control group received lysozyme of RA eye drops. The corneal morphology changes, conjunctival goblet cell count and corneal neovascularization area were measured. The number of inflammatory cells and expression of inflammatory factor in the corneal line of rat were observed by HE staining and immunohistochemical staining. Results The corneal neovascular area and inflammatory cell count after corneal alkali burn in RA group were lower than those of the control group. The conjunctival goblet cells count were higher than those of the control group at 4 and 7 days after corneal alkali burn, the difference was not significant at 14 days after corneal alkali burn. The expression of IL-1α, NF-κB and VEGF in the RA group were lower than those in the control group at 4 and 7 days after corneal alkali burn. At 14 days after corneal alkali burn, the VEGF expression in the RA group was lower than that of the control group, but the difference in the expression of IL-1α and NF-κB were not significant between the two group (IL-1α: 1.84±0.15 and 2.01±0.19, t=-2.26, P=0.347; NF-κB: 1.83±0.35 and 2.00±0.33, t=-2.59, P=0.695). Conclusion RA can control corneal inflammatory reaction and neovascularization by inhibiting the expression of IL-1α, NF-κB and VEGF. RA is effective for the treatment of alkali corneal burn. Key words: Retinoic acid; Burn, alkali, corneal; Neovascularization