The Importance of Antioxidant Micronutrients in Pregnancy
Figure 2
Major pathways of reactive oxygen species generation and metabolism. Superoxide can be generated by specialised enzymes, such as the xanthine or NADPH oxidases, or as a byproduct of cellular metabolism, particularly the mitochondrial electron transport chain. Superoxide dismutase (SOD), both Cu/Zn and Mn SOD, then converts the superoxide to hydrogen peroxide (H2O2) which has to be rapidly removed from the system. This is generally achieved by catalase or peroxidases, such as the selenium-dependent glutathione peroxidases (GPxs) which use reduced glutathione (GSH) as the electron donor.
