Evaluation of the effectiveness of epigallocatechin gallic acid, resveratrol, and autologous serum in an alkaline eye injury model

PURPOSE: To compare the efficacy of green tea extract (epigallocatechin gallate – EGCG) and resveratrol with autologous serum (AS) in a chemical eye injury.
METHODS: A total of 17 New Zealand rabbits were divided into 5 groups (3 treatment groups, 1 sham, and 1 control group). A membrane filter paper impregnated with 10% potassium hydroxide was placed over the right eyes of the rabbits under sedation for 30 seconds to induce a chemical burn. Next, the ocular surfaces were washed with 0.9% saline for 10 minutes. EGCG solution was applied to the rabbits in Group 1, resveratrol solution to Group 2, and 20% AS to Group 3 for 3 weeks. In all groups, 0.9% saline was applied to the left eyes for 3 weeks (sham). Two corneas were left untreated after the chemical burn as a control. All groups were photographed daily for 3 weeks. Afterwards, the rabbits were sacrificed, the corneas were excised, and examined histopathologically with Hematoxylin & Eosin, Masson Trichrome, PAS staining, and immunohistochemically for GFAP, Ki-67, NF-kB, and IL-17 expression.
RESULTS: Clinically: AS was the only agent that clinically decreased the epithelial defect compared to the pre-treatment status. Histologically: Neuronal regeneration was higher in Group 2. Innate immune and inflammatory responses, as well as regeneration, were superior in Group 1.
CONCLUSION: EGCG and AS, but not resveratrol, could stimulate corneal healing in chemical eye injuries. More studies are needed to determine the optimal dose of EGCG and obtain a clinical response.

Keywords: Epigallocatechin gallic acid, ocular burn, ocular chemical injury, resveratrol.