Superoxide Dismutase & Peroxidase Antioxidant Enzymes

Superoxide dismutase is a term representing a class of antioxidant enzymes (usually containing copper, zinc, and/or manganese) that catalyze the breakdown/transformation (known as dismutation) of superoxide free radicals into oxygen and hydrogen peroxide. In humans and most other mammal there are three forms of superoxide dismutase: SOD1 that is contained in the cytoplasm, SOD2 that is contained in mitochondria, and SOD3 that is contained in the extracellular fluid. All three are similar in structure and basic functioning of neutralizing the superoxide free radical form of reactive oxygen species (ROS). The superoxide free radical is formed as a normal part of cellular respiration in the mitochondria when O2 (oxygen) is reduced to O2- (superoxide) when it absorbs an excited electron released from compounds of the electron transport chain. Superoxide free radicals are known to denature enzymes, oxidize lipids, and fragment DNA. Superoxide dismutases catalyze the production of O2 (oxygen) and H2O2 / HO (hydrogen peroxide) from O2- (superoxide), which results in less harmful reactants.

Peroxidases are also antioxidant enzymes, similar to superoxide dismutases, that catalyze the dismutation of hydrogen peroxide. In the same way that superoxide dismutase usually contains copper, zinc, and/or manganese, peroxidases usually contain glutathione or selenium (both important antioxidants found abundantly in the skin and body). It is important that peroxidases be supplied alongside superoxide dismutases in skincare formulas as they are able to neutralize any potential free radical damage from hydrogen peroxide that can form when superoxide dismutases are neutralizing superoxide free radicals. While superoxide dismutases are one of the most important antioxidants, if not the most important antioxidant, used by every cell in the body, it is peroxidase that provides superoxide dismutase with supplemental support to neutralize secondary free radicals that are sometimes formed when superoxide dismutases are catalyzing the breakdown of superoxide free radicals.