Oral Resveratrol Versus Crocin in Experimental Alkali–Induced Corneal Injury: Comparative Effects on Corneal Opacity, Epithelial Repair, Neovascularization, and Edema in Rats

Purpose: To compare orally administered crocin and resveratrol on clinical and image-derived corneal outcomes in a rat model of alkali-induced corneal injury. Methods: Right corneal alkali burns were induced in rats allocated to vehicle control ( n = 14), crocin 100, 200, or 300 mg/kg/day, or resveratrol 100, 200, or 300 mg/kg/day ( n = 7 per treatment group). Treatments were administered once daily by oral gavage for 42 days. Epithelial defect area, corneal opacity area, corneal neovascularization area, corneal edema score, and clinical corneal opacity score were assessed serially. Results: Corneal opacity area showed a significant Day × Group interaction ( P = 0.034). At day 42, opacity area was highest in controls (33.96% ± 4.12%) and lowest in the resveratrol 300 mg/kg/day group (14.34% ± 2.19%), followed by resveratrol 200 mg/kg/day (19.50% ± 4.11%). Clinical opacity score at day 42 was 2.00 ± 0.00 in controls, 1.00 ± 0.00 in all crocin groups and resveratrol 100 mg/kg/day, 0.86 ± 0.38 in resveratrol 200 mg/kg/day, and 0.00 ± 0.00 in resveratrol 300 mg/kg/day. At day 10, epithelial defect area was lowest in resveratrol 300 mg/kg/day (0.31% ± 0.83%), followed by resveratrol 200 mg/kg/day (1.27% ± 1.81%) and crocin 300 mg/kg/day (1.49% ± 2.55%), compared with controls (7.24% ± 2.11%). At day 42, the neovascularization area was lowest in resveratrol 300 mg/kg/day (27.10% ± 1.93%) versus controls (48.15% ± 2.09%). Conclusions: Oral crocin and resveratrol improved corneal healing after alkali injury. High-dose resveratrol showed the most consistent benefit for corneal opacity, epithelial closure, and neovascularization, supporting further mechanistic and dose-optimization studies.