Superoxide dismutase (SOD) in normal and cataractous human lenses

Normal human lenses removed from eye bank eyes and cataractous lenses were assayed for superoxide dismutase (SOD) activity. In normal whole human lenses, SOD shows no marked difference in activity during aging. When comparing the activity in the nucleus with that in the equator, one finds that the activity in both lens parts has decreased with increasing age. The mean values of SOD are significantly lower in human lenses with mature cataract than in clear lenses. Interestingly, no residual activity could be proved in mature cataracts, whereas the activity in posterior subcapsular cataracts lay within normal limits.