Polyunsaturated fatty acid lipid radicals (Lipid radicals) (Lipid radicals)

Lipid radicals in polyunsaturated fatty acids (PUFAs) are highly reactive chemical species generated during the process of lipid peroxidation within cellular membranes (Yin et al., 2011, Chemical Reviews). These radicals, including lipid peroxyl (LOO•) and lipid alkoxyl (LO•) radicals, are formed when reactive oxygen species (ROS) or enzymes like lipoxygenases abstract a hydrogen atom from the methylene groups of PUFAs (Conrad et al., 2018, Nature Chemical Biology). This initiates a self-propagating chain reaction that compromises membrane integrity and produces toxic byproducts like malondialdehyde and 4-hydroxynonenal (PubMed: 21443212). In the context of human health, these radicals are central to ferroptosis, a form of regulated cell death characterized by iron-dependent lipid peroxidation (Dixon et al., 2012, Cell). Therapeutic strategies often focus on neutralizing these radicals using small-molecule antioxidants or radical-trapping antioxidants (RTAs) like ferrostatin-1 and liproxstatin-1 to prevent cell death in neurodegenerative and ischemic diseases (StatPearls: Free Radicals). Conversely, inducing the formation of these radicals is a burgeoning strategy in oncology to trigger ferroptotic death in therapy-resistant cancer cells (NIH: Ferroptosis in Cancer).

Other names

Lipid peroxyl radicalsLipid alkoxyl radicalsPUFA radicalsLipid hydroperoxide radicalsLOO•LO•Membrane lipid radicals

Radical-trapping antioxidants (RTAs) inhibit the propagation of lipid peroxidation by scavenging lipid peroxyl radicals, thereby preventing membrane damage and ferroptotic cell death.