Reactive oxygen species and related redox systems (ROS) (ROS)

Reactive oxygen species (ROS) and related redox systems encompass a broad array of oxygen-derived free radicals and non-radical species, such as superoxide, hydrogen peroxide, and hydroxyl radicals, along with the enzymatic and non-enzymatic systems that regulate them [1, 13]. In physiological conditions, ROS serve as critical signaling molecules in processes like cell proliferation, immune defense, and vascular tone [1, 14]. However, an imbalance between ROS production and antioxidant defense leads to oxidative stress, causing damage to DNA, proteins, and lipids [7, 11]. This dysregulation is a hallmark of various pathologies, including cancer, neurodegeneration, and cardiovascular diseases [1, 7]. Therapeutic interventions typically aim to either scavenge excess ROS directly or enhance the body's natural antioxidant capacity through the modulation of redox-sensitive pathways like the Nrf2-KEAP1 system [5, 6]. Conversely, some therapies utilize pro-oxidant mechanisms to selectively induce apoptosis in cancer cells [2, 9].

Other names

Oxidative stress systemRedox signaling networkReactive oxygen species (ROS)Reactive nitrogen species (RNS)Antioxidant defense system

Therapeutic strategies involve direct scavenging of free radicals, induction of endogenous antioxidant enzymes via Nrf2 activation, or inhibition of ROS-generating enzymes such as NADPH oxidase (NOX) and xanthine oxidase (XO) [1, 5, 8]. Additionally, pro-oxidant drugs may be used to elevate ROS levels beyond the toxic threshold in cancer cells to trigger apoptosis [2, 6, 9].