GSR and Parkinson disease: In their WB cells, PD patients exhibited significantly lower and higher glutathione peroxidase (GPx) (p < 0.01; Figure 3A) and glutathione reductase (GR) (p < 0.05; Figure 3B) activities, respectively, as well as higher oxidized glutathione (GSSG) (p < 0.05; Figure 3D) and malondyaldehide (MDA) (p < 0.001; Figure 3F) contents than elderly subjects.