Lipid hydroperoxide (LOOH)

Lipid hydroperoxides are primary oxidation products formed when lipids—especially polyunsaturated fatty acids in biological membranes—undergo peroxidation due to attack by reactive oxygen species such as hydroxyl radicals or singlet oxygen. The process involves three phases: initiation, propagation, and termination. During propagation, lipid radicals react with molecular oxygen to form lipid peroxyl radicals and ultimately lipid hydroperoxides. These molecules are more polar than their parent lipids and can disrupt membrane structure and function[8]. They serve as intermediates in oxidative stress responses and can be further reduced enzymatically by glutathione peroxidases or degraded into secondary products like aldehydes (e.g., malondialdehyde [MDA], 4-hydroxynonenal [4-HNE]), which themselves have significant biological activity including acting as signaling molecules or inducing cell death pathways such as ferroptosis[2][5]. Accumulation of lipid hydroperoxides is implicated in the pathogenesis of various diseases including cancer, neurodegeneration, cardiovascular diseases, inflammation-related conditions, and skin disorders due to their ability to perturb cellular membranes and modulate redox-sensitive signaling pathways[2][5][8]. While not a classical therapeutic target like a receptor or enzyme but rather a class of reactive metabolites/biomarkers produced during oxidative damage processes—they are important both mechanistically in disease biology and diagnostically for monitoring oxidative stress states[1][2][7].

Other names

Lipid peroxideLOOHlipid hydroperoxides (plural)phospholipid hydroperoxidecholesterol hydroperoxide (ChOOH)squalene hydroperoxide (SQOOH)