Reactive oxygen species and reactive nitrogen species (ROS and RNS)

Reactive oxygen species (ROS) and reactive nitrogen species (RNS) are families of chemically reactive molecules derived from oxygen and nitrogen, respectively, many of which are free radicals[3][1][5]. Examples include superoxide anion (O₂•⁻), hydrogen peroxide (H₂O₂), hydroxyl radical (•OH) for ROS, and nitric oxide (•NO), peroxynitrite (ONOO⁻), and nitrogen dioxide radical for RNS[3][1][5]. They are natural byproducts of cellular metabolism and play dual roles in biology: at physiological levels, they are crucial signaling molecules that regulate various cellular processes, while in excess, they can cause oxidative or nitrosative stress, leading to cellular damage[2][4][7]. Dysregulated levels are associated with a range of diseases, including cancer, cardiovascular and neurodegenerative disorders, and inflammatory conditions[2][4][6]. ROS and RNS are typically not considered direct therapeutic targets but are modulated indirectly through antioxidants, enzyme inhibitors, or redox-active drugs[5]. Their roles are context-dependent, displaying both pathological and physiological effects depending on their concentration, location, and the presence of cellular antioxidants[4][2]. Because "Reactive oxygen species and reactive nitrogen species" collectively refers to a broad chemical group, it is not a classic "target" in the therapeutic sense; it is a collective term and thus "is_incorrect: true" under your schema[1][3][5]. For structured drug discovery purposes, refer instead to specific enzymes (e.g., NADPH oxidases, nitric oxide synthases) or define single reactive species when a specific target is required.

Other names

ROSRNSOxygen free radicalsNitrogen free radicalsReactive oxygen intermediates (ROIs)Reactive nitrogen intermediates (RNIs)

Scavenging/neutralizing reactive species (antioxidants); Inhibition of ROS/RNS generating enzymes (e.g., NADPH oxidase inhibitors, NOS inhibitors)