Ocular tissues and fluids oxidative stress in hares fed on verbascoside supplement.

The influence of a prolonged diet supplemented with the powerful antioxidant verbascoside on the oxidative state of 20 healthy hares eye fluids and tissues has been studied. Verbascoside was dosed at 2, 3, 4 mg/die and the impact on the oxidative state of ocular tissues and fluids was tested by TBARS (thio barbituric acid reactive substances) and TEAC (trolox equivalent antioxidant capacity) assays. The percentage of change in antioxidant activity increased largely in retina and lenses at a daily verbascoside dose of 3 mg, whereas for optic nerve and vitreous humor the higher antioxidant capacity was measured at 4 mg/die verbascoside dose. The present findings demonstrate that verbascoside supplementation is able to protect ocular tissue and fluids from naturally occurring oxidation and that its protective effect depends on the daily dose, being maximum up to 3 mg/die.