Prevention of Selenite-Induced Cataratogenesis by Ginkgo biloba Extract (Egb761) in Wistar Rats

Objective: To investigate whether Ginkgo biloba extract retards selenite-induced cataractogenesis in Wistar rat pups. Methods: On postpartum day eight, Group I rat pups (n = 12) received an intraperitoneal injection of physiological saline. Groups II and III rat pups (n = 12) received a subcutaneous injection of sodium selenite. Group III also received an intraperitoneal injection of G. biloba extract once daily on postpartum days 9-14. Both eyes of each pup were examined from postpartum day 16 up to day 30. After sacrifice, encapsulated pup lens were analyzed for mean activities of catalase, superoxide dismutase, glutathione peroxidase (GPx), glutathione S-transferase and glutathione reductase. In addition, the mean concentrations of reduced glutathione (GSH) and malondialdehyde were analyzed in samples of lens and serum. Results: Dense lenticular opacification occurs 100% in Group II, but only minimal opacification occurs in three pups of Group III (25%), no opacification in 75% of Group III, none in Group I. Compared with Groups I and III, Group II rat showed lower lenticular antioxidant enzyme activity, lower level of GSH, and higher level of malondidehyde (mean +/- standard deviation SD, p<0.05 respectively). Conclusions: The treatment with G. biloba extract is effective against oxidative stress - a crucial factor of cataractogenesis in rat pups, possibly by preventing depletion of antioxidant enzymes and by inhibiting lipid peroxidation.