[Changes of Glutathione Peroxidase Activity in Eye Tissues of Emory Mice in Relation to Cataract Status and Age]

The relationship between the activity of the antioxidant defense enzyme glutathione peroxidase (GSH-PX) and the degree of cataract (lens opacity) was examined in 14 Emory mice at the age of 2, 7 and 10 months. Significant decreases in specific GSH-PX activity (mU/mg wet tissue) in the lens as well as in the residual eye tissue were found between 2 and 10 months of age, showing a highly significant correlation of this decrease (r = 0.590, p approximately 0.001) with the increasing degree of turbidity of the lenses. The results are discussed with regard to the changes of antioxidant mechanisms during cataractogenesis and aging. The role of the maintenance of an optimal level of GSH-PX and other well-known antioxidants (enzymes, vitamins, trace elements including iodide) for a delay of cataractogenesis is pointed out.