Reactive oxygen species and lipid peroxyl radicals (ROS) (ROS)

Reactive oxygen species (ROS) and lipid peroxyl radicals are highly reactive chemical entities generated as byproducts of aerobic metabolism or in response to environmental stressors. In biological membranes, these species initiate and propagate lipid peroxidation, a self-sustaining chain reaction that damages polyunsaturated fatty acids, leading to the loss of membrane fluidity and integrity (Gaschler & Stockwell, 2017, Nature Chemical Biology). While low levels of ROS are essential for physiological cell signaling and immune defense, excessive accumulation—termed oxidative stress—is a hallmark of numerous pathological conditions, including neurodegenerative diseases like Alzheimer's and cardiovascular disorders (Sies et al., 2017, Nature Reviews Molecular Cell Biology). Pharmacological intervention typically involves the use of antioxidants or radical scavengers, such as edaravone or vitamin E, which neutralize these radicals to prevent cellular injury (Cho et al., 2018, Drug Design, Development and Therapy). However, these species are not traditional therapeutic targets like receptors or enzymes; rather, they are reactive intermediates whose levels are modulated by drugs. Monitoring efficacy often relies on biomarkers of oxidative damage, such as malondialdehyde (MDA) or 8-isoprostane (Tsikas, 2017, Journal of Chromatography B). Therapeutic challenges include the difficulty of achieving site-specific delivery and the risk of disrupting essential redox-sensitive signaling pathways.

Other names

ROSLipid peroxyl radicalsFree radicalsOxidantsLipid peroxidesReactive oxygen intermediates

Direct scavenging of free radicals and neutralization of reactive oxygen species to terminate lipid peroxidation chain reactions and prevent oxidative damage to cellular membranes.