Reactive oxygen and nitrogen species and oxidized thiols (RONS)

Reactive oxygen and nitrogen species (RONS) are a diverse group of highly reactive molecules, including free radicals like superoxide and hydroxyl radicals, as well as non-radicals like hydrogen peroxide and peroxynitrite. They are produced as natural byproducts of aerobic metabolism and play critical roles in cell signaling and the immune response, particularly during the oxidative burst used by phagocytes to destroy pathogens (NIH, 2022). Oxidized thiols refer to the modification of cysteine residues within proteins, which can act as redox switches to regulate enzymatic activity and structural integrity (PubMed, 2021). When the production of RONS exceeds the capacity of cellular antioxidant defenses, a state of oxidative stress occurs, leading to the damage of lipids, proteins, and DNA. This damage is a hallmark of numerous pathologies, including neurodegenerative diseases like Alzheimer's and various cardiovascular conditions (StatPearls, 2023). Therapeutic intervention typically involves the use of antioxidants or scavengers that directly interact with these species to neutralize them or reduce oxidized protein thiols back to their functional states. However, because RONS are also vital for normal physiological signaling, non-specific targeting remains a significant challenge in drug development.

Other names

Reactive oxygen speciesReactive nitrogen speciesROSRNSOxidized thiol groupsFree radicalsOxidative stress mediatorsRedox-active species

Direct scavenging of free radicals, neutralization of reactive oxygen/nitrogen intermediates, and reduction of oxidized cysteine thiol groups to restore cellular redox balance.