Reactive oxygen and nitrogen species and metal ions in enzyme active sites

Reactive oxygen and nitrogen species (RONS) and metal ions in enzyme active sites represent a broad category of chemical mediators and catalytic centers central to cellular redox homeostasis [1]. RONS, such as superoxide and nitric oxide, function as signaling molecules in processes like vasodilation and immune response, but their overproduction leads to oxidative and nitrosative stress, damaging cellular components [1, 3]. Metal ions, including iron, copper, and zinc, are essential cofactors in metalloenzymes that facilitate complex biochemical reactions; however, when improperly regulated, they can catalyze the formation of highly toxic hydroxyl radicals via Fenton-like chemistry [2]. This collective system is implicated in the pathogenesis of various conditions, including neurodegenerative diseases, cardiovascular disorders, and cancer [3]. Therapeutic strategies focus on neutralizing these reactive species using antioxidants, sequestering metal ions with chelators, or inhibiting the specific enzymes responsible for RONS generation, such as NADPH oxidase or nitric oxide synthase [1, 3]. These interventions aim to restore redox balance and prevent the irreversible damage to proteins, lipids, and nucleic acids that characterizes chronic disease states [3].

Other names

Reactive Oxygen SpeciesReactive Nitrogen SpeciesMetalloenzyme Active SitesROS/RNSRedox-active Metal Ions

Direct scavenging of reactive species, chelation of transition metal ions to prevent radical formation, or catalytic mimicry of endogenous antioxidant enzymes.