Antioxidant enzyme system and reactive oxygen species (ROS/Antioxidant System)

The antioxidant enzyme system and reactive oxygen species (ROS) represent a complex physiological network that maintains cellular redox homeostasis by balancing the production and neutralization of highly reactive oxygen-containing molecules (Sies et al., 2022, Nature Reviews Molecular Cell Biology). ROS, including superoxide anions and hydrogen peroxide, are generated as byproducts of mitochondrial metabolism and by specialized enzymes like NADPH oxidases (NOX), serving as essential signaling molecules for cell growth and immune defense (Forman & Zhang, 2021, Nature Reviews Drug Discovery). To prevent oxidative damage, cells employ an enzymatic defense suite including superoxide dismutase (SOD), catalase, and glutathione peroxidase (GPx), which convert reactive species into less harmful molecules like water and oxygen (Pizzino et al., 2017, Oxidative Medicine and Cellular Longevity). Chronic imbalance, known as oxidative stress, leads to the degradation of lipids, proteins, and DNA, contributing significantly to the progression of cancer, cardiovascular diseases, and neurodegeneration (He et al., 2020, Signal Transduction and Targeted Therapy). Therapeutic approaches targeting this system include direct ROS scavengers, antioxidant enzyme mimetics, and Nrf2 activators that induce the expression of endogenous antioxidant genes (StatPearls, 2023). Despite their potential, clinical success has been limited by the difficulty of selectively targeting pathological ROS without disrupting vital physiological signaling pathways (PubMed, 2022).

Other names

Redox homeostasis systemOxidative stress pathwayROS scavenging systemAntioxidant defense system

Direct scavenging of reactive oxygen species, mimicry of endogenous antioxidant enzymes, and induction of the Nrf2-mediated antioxidant response (Nature Reviews Drug Discovery, 2021).