Reactive oxygen species and redox-active transition metals (ROS/Metals)

Reactive oxygen species (ROS) and redox-active transition metals, primarily iron and copper, are fundamental mediators of cellular redox biology and oxidative stress (Sies & Jones, 2020, Nature Reviews Molecular Cell Biology). ROS are oxygen-derived molecules, including superoxide and hydrogen peroxide, that function as secondary messengers in physiological signaling pathways but can cause extensive damage to lipids, proteins, and DNA when overproduced (Halliwell & Gutteridge, 2015, Free Radicals in Biology and Medicine). Redox-active transition metals facilitate this damage by catalyzing the Fenton and Haber-Weiss reactions, which generate the highly toxic hydroxyl radical from less reactive precursors (Jomova & Valko, 2011, Toxicology). This synergy is a hallmark of oxidative stress and is implicated in the progression of numerous pathologies, including Alzheimer's disease, atherosclerosis, and various cancers (Fiedor & Burda, 2014, Nutrients). Pharmacological intervention typically focuses on antioxidant scavengers to neutralize ROS or chelating agents to sequester labile metals, aiming to restore redox balance (PubChem, 2024). However, because ROS also play essential roles in immune defense and intracellular signaling, non-specific targeting can lead to significant toxicity or a lack of clinical efficacy.

Other names

Oxidative stress mediatorsFree radicalsLabile metal poolPro-oxidantsReactive oxygen speciesRedox-active metals

Neutralization of reactive species through electron donation (scavenging) or sequestration of catalytic metal ions (chelation) to inhibit the formation of highly reactive hydroxyl radicals via Fenton chemistry.