Reactive oxygen species and redox-active cellular components (ROS)

Reactive oxygen species (ROS) and redox-active cellular components represent a diverse group of oxygen-derived molecules, including free radicals like superoxide (O2•−) and non-radicals like hydrogen peroxide (H2O2), which are essential for cellular homeostasis [1]. These species are primarily generated as byproducts of mitochondrial oxidative phosphorylation and by specialized enzymes such as NADPH oxidases [2]. At physiological concentrations, ROS function as critical signaling molecules in processes like cell proliferation, differentiation, and the innate immune response [1][3]. However, an imbalance between ROS production and the capacity of antioxidant systems (e.g., glutathione, superoxide dismutase) leads to oxidative stress, causing cumulative damage to DNA, proteins, and lipids [3]. This oxidative damage is a central driver in the pathogenesis of cancer, neurodegenerative diseases like Amyotrophic Lateral Sclerosis (ALS), and cardiovascular disorders [2][4]. Therapeutic interventions, such as the drug edaravone, target these species by acting as free radical scavengers to mitigate tissue damage [5]. Despite their therapeutic potential, the non-specific nature of ROS and their requirement for normal signaling pose significant challenges, as excessive suppression can disrupt vital physiological functions [1][3].

Other names

Free radicalsOxidantsReactive oxygen metabolitesRedox-active speciesReactive oxygen species

Direct scavenging of free radicals, neutralization of reactive oxygen species, and enhancement of endogenous antioxidant defense systems.