Purpose: The present study sought to investigate whether Crocus sativus stigmas (saffron) extract prevents selenium-induced cataractogenesis in vivo, and to study its possible protective mechanism.
Methods: Wistar rat pups were randomized into three groups. Group I (control) received subcutaneous injection of normal saline on postnatal day 10. Groups II (selenite-treated) and III (selenite+saffron-treated) received subcutaneous injection of sodium selenite (20 µmol/kg body weight) on postnatal day 10. Group III also received intraperitoneal injections of saffron extract (60 mg/kg body weight) on postnatal days 9 and 12. On postpartum day 21, rats were sacrificed and the lenses were isolated and examined for cataract formation. Activities of superoxide dismutase, glutathione peroxidase, catalase, and glutathione levels, as markers of antioxidant defense, were measured in the isolated lenses. Levels of the indicator of lipid peroxidation, malondialdehyde, and protein oxidation (sulfhydryl content) in the lens were also determined. The effect of the different treatments on lens protein profile was evaluated through an estimation of the soluble to insoluble protein ratio and sodium dodecyl sulfate polyacrylamide gel electrophoresis analysis of the water-soluble fraction (WSF) of lens proteins.
Results: Saffron demonstrated significant protection against selenite-induced cataractogenesis in vivo. The mean activities of superoxide dismutase, glutathione peroxidase, catalase, and glutathione levels were significantly increased in group III compared to the selenite-treated group. Saffron significantly prevented selenite-induced lipid peroxidation, protein oxidation, and proteolysis and insolubilization of the lens WSF.
Conclusions: Saffron extract prevented selenite-induced cataract formation in Wistar rats, possibly through the reinforcement of antioxidant status, reduction of the intensity of lipid peroxidation, protection of the sulfhydryl groups, and inhibition of proteolysis of the lens WSF. These findings highlight the anticataractogenic potential of saffron by virtue of its antioxidant property.