Normally endogenous enzymatic antioxidant
supplies which more potent than nonenzymatic
antioxidant and are depleted far less quickly
o Superoxide dismutase (SOD): enzymatic proteins being Mn-SOD, Cu-Zn-SOD
SOD activity enhances the dismutation of superoxide radicals to
hydrogenperoxide
o Catalase (CAT):
Remove the end products from dismutation (H2O2
) (at high concentration)
o Glutathione peroxidase (GSHPx)
Reduce hydrogenperoxide H2O2
to water (even though H2O2
is low
concentration)
Reduce lipid hydroperoxides to corresponding alcohol which was nontoxic