Effects of vitamin E in a glucocorticoid induced cataract model in chicken embryos.

We investigated the antioxidant effects of vitamin E on a glucocorticoid (GC) induced model of cataracts in chick embryos. We used 70 fertilized eggs divided into seven groups as follows: phosphate-buffered saline (PBS) group, olive oil treatment (OO) group, hydrocortisone treatment (HC) group, olive oil and hydrocortisone treatment (OO + HC) group, 50 mg/kg vitamin E and hydrocortisone treatment (HC + VE (50)) group, 25 mg/kg vitamin E and hydrocortisone treatment (HC + VE (25)) group and 15 mg/kg vitamin E and hydrocortisone treatment (HC + VE (15)) group. On day 17, chick embryos were removed from the eggs and lens and liver tissues were excised. Cataract formation was evaluated and total antioxidant status (TAS), total oxidant status (TOS), malondialdehyde (MDA) and glutathione peroxidase (GPx) were measured in lens and liver tissues; MDA was measured only in liver. The lenses in the HC + VE (50) group exhibited significantly higher levels of GPx and TAS, and lower levels of TOS than for HC and OO + HC groups. The livers of the HC + VE (50) group exhibited significantly higher levels of GPx and lower levels of MDA than for the HC and OO + HC groups. The HC + VE (50) group lenses were evaluated as grade 1, because the nuclei were completely free of cataracts, likely due to the antioxidative effect of high dose VE. VE is an effective antioxidant agent that exhibits a dose-response effect, for ameliorating the negative effects of GCs.