GSR and obesity due to melanocortin 4 receptor deficiency: Moreover, the erythrocyte activities of superoxide dismutase (SOD), catalase, glutathione peroxidase (GPX), glutathione reductase (GR), and reduced glutathione concentration (GSH) were lower in obese children aged 6–12 years than their counterparts, whereas these antioxidant activities in erythrocyte (59) and serum TAS (29) were increased in overweight compared to normal-weight children aged 7–15 years, suggesting the inability to counterbalance the detrimental effects or the highly production of ROS in obesity.