Redox Regulation in Animals for Slowing Ageing

Utilization of oxygen in varieties of biochemical reactions especially, in mitochondrial electron transport chain (ETC) to reduce O2 to H2O in aerobic organisms, lead to produce several active oxygen molecules. So, mainly ETC acts as the main hub in producing partially reduced O2, as several active oxygen species. These intermediate molecules are commonly known as reactive oxygen species (ROS; such as superoxide radical, hydroxyl radical and hydrogen peroxide). ROS being highly cytotoxic in nature produce deleterious effects on biomolecules. They can oxidize biomolecules non-specifically to produce lipid peroxides, protein carbonyls and nucleic acid adducts from lipids, proteins and nucleic acids, respectively [1]. When these important bio-molecules are damaged, cells are pushed to a stress condition called as oxidative stress. Cells have their own redox regulating system by using which they control the levels of the over produced ROS. Commonly, it is called as antioxidant defense system. Antioxidant defense system protects cells from the oxidation, done by the oxidants or ROS. Antioxidant defense system constitutes enzymatic and non-enzymatic molecules. Non-enzymatic antioxidant defense system is mainly constituted by small redox regulatory molecules (such as reduced glutathione (GSH), ascorbic acid (AA), carotenoids etc). Enzymatic antioxidant constitutes a cascade of enzymes namely superoxide dismutase (SOD, EC1.15.1.1), catalase (CAT, EC 1.11.1.6) and glutathione peroxidase (GPx, EC1.11.1.9) [2].