Reactive oxygen species and antioxidant defense pathways (ROS/Antioxidant pathways)

Reactive oxygen species (ROS) and antioxidant defense pathways constitute a complex biochemical network essential for maintaining cellular redox homeostasis (Sies et al., 2017, Nature Reviews Molecular Cell Biology). ROS, including superoxide and hydrogen peroxide, are generated as metabolic byproducts and function as vital signaling molecules in processes such as cell growth and immune activation (Finkel, 2011, Nature). However, an imbalance—termed oxidative stress—occurs when ROS production exceeds the neutralizing capacity of antioxidant defenses like superoxide dismutase, catalase, and the glutathione system, leading to oxidative damage to DNA, proteins, and lipids (Halliwell & Gutteridge, 2015, Free Radicals in Biology and Medicine). This pathway-level modulation is a major therapeutic strategy for conditions where oxidative stress is a primary driver, such as neurodegenerative diseases (e.g., Alzheimer's), cardiovascular disorders, and chronic inflammation (Forman & Zhang, 2021, Nature Reviews Drug Discovery). Pharmacological interventions aim to restore balance by either directly scavenging radicals or activating the Nrf2-mediated antioxidant response element (ARE) pathway to upregulate endogenous protective enzymes (He et al., 2020, Signal Transduction and Targeted Therapy).

Other names

Oxidative stress response pathwayRedox signaling pathwayROS metabolismAntioxidant defense systemCellular redox homeostasis

Modulation of the cellular redox state through the induction of endogenous antioxidant enzymes via the Nrf2/ARE signaling axis, direct chemical scavenging of reactive species, or the inhibition of ROS-generating enzymes such as NADPH oxidase (Pizzino et al., 2017, Oxidative Medicine and Cellular Longevity; He et al., 2020, Signal Transduction and Targeted Therapy).