SOD1 and type 2 diabetes mellitus: In this regard, melatonin supplementation in these ZDF rats has been shown to lower basal and Fe2+/H2O2-induced plasma lipid peroxidation by improving low-grade inflammation and oxidative stress in this animal model of obesity and T2DM [31], which could be related to an increase in Zn, Cu-SOD activity in skeletal muscle, which is primarily responsible for the uptake and expenditure of most blood glucose.