Free radicals and lipid peroxyl radicals (ROS/LOO•)

Free radicals and lipid peroxyl radicals are highly reactive chemical species characterized by the presence of unpaired electrons, making them prone to initiating oxidative damage within biological systems [1]. Lipid peroxyl radicals, specifically, are central to the process of lipid peroxidation, where they propagate a chain reaction that degrades polyunsaturated fatty acids in cellular and organelle membranes [2]. This process not only compromises membrane integrity but also generates secondary toxic products such as malondialdehyde (MDA) and 4-hydroxynonenal (4-HNE), which can form harmful adducts with proteins and DNA [2]. While low levels of reactive oxygen species (ROS) serve as important signaling molecules, an imbalance—termed oxidative stress—is a hallmark of numerous pathologies, including atherosclerosis, Alzheimer's disease, and various cancers [3]. Pharmacological intervention typically involves the use of radical scavengers or chain-breaking antioxidants designed to donate electrons and stabilize these radicals, thereby halting the cycle of oxidative damage [4]. Drugs like edaravone are specifically indicated to scavenge these radicals to mitigate neuronal damage in conditions like amyotrophic lateral sclerosis [5]. Sources: [1] Phaniendra, A., et al. (2015). Free Radicals: Properties, Sources, Targets, and Their Implication in Various Diseases. Indian Journal of Clinical Biochemistry. [2] Ayala, A., et al. (2014). Lipid Peroxidation: Production, Metabolism, and Signaling Mechanisms of Malondialdehyde and 4-Hydroxy-2-Nonenal. Oxidative Medicine and Cellular Longevity. [3] Lobo, V., et al. (2010). Free radicals, antioxidants and functional foods: Impact on human health. Pharmacognosy Reviews. [4] Nimse, S. B., & Pal, D. (2015). Free radicals, natural antioxidants, and their mechanisms of action. RSC Advances. [5] Watanabe, K., et al. (2018). How is edaravone effective against ALS? Medical Gas Research.

Other names

Reactive oxygen speciesROSLipid peroxidesOxidantsPeroxyl radicalsHydroperoxyl radicals

Radical scavenging and chain-breaking antioxidant activity to neutralize reactive species and prevent the propagation of lipid peroxidation.