Lipid peroxyl radical (LOO•) (LOO•)

Lipid peroxyl radicals (LOO•) are highly reactive chemical species formed during the propagation phase of lipid peroxidation, a chain reaction that causes oxidative damage to polyunsaturated fatty acids (PUFAs) in cellular membranes (Ayala et al., 2014). These radicals are generated when a carbon-centered lipid radical reacts rapidly with molecular oxygen; the resulting peroxyl radical then abstracts a hydrogen atom from a neighboring lipid molecule, creating a lipid hydroperoxide and a new lipid radical to continue the cycle (Niki, 2014). This process leads to the loss of membrane integrity, altered fluidity, and the formation of toxic secondary products like malondialdehyde and 4-hydroxynonenal, which can damage proteins and DNA (Gaschler & Stockwell, 2017). Lipid peroxyl radicals are key drivers of ferroptosis, a form of regulated cell death characterized by iron-dependent lipid peroxidation (Stockwell et al., 2017). Pharmacological intervention typically involves chain-breaking antioxidants, such as Vitamin E or specialized small molecules like Ferrostatin-1, which donate a hydrogen atom to the peroxyl radical to terminate the chain reaction (Zelkas et al., 2020). These radicals are implicated in the progression of atherosclerosis, neurodegenerative diseases like Alzheimer's, and various inflammatory disorders (Milne et al., 2005).

Other names

Peroxyl radicalLipid peroxylLOO.ROO.Lipid hydroperoxyl radical

Chain-breaking antioxidant activity via hydrogen atom transfer (HAT) to neutralize the radical and terminate the lipid peroxidation chain reaction.