Erythrocyte antioxidant system in Down syndrome.

It has been emphasized that an increased oxidative damage can exist in Down syndrome (DS), and that superoxide dismutase (SOD-1) seems to play a role in the pathogenesis of this disorder. We have studied the antioxidant system SOD-1, catalase, glutathione peroxidase (GSH-Px) and reduced glutathione (GSH) in erythrocytes of DS adults in order to evaluate if these cells are protected against oxidant stress. SOD-1 and GSH-Px were significantly increased while catalase and GSH activities were normal. These results suggest that the erythrocytes of these individuals have an unbalanced antioxidant system which may participate in the manifestations of DS.