title: Cholesterol hydroperoxides and their degradation mechanism.
abstract: Cholesterol is one of the oxidizable lipids constituting biomembranes and plasma lipoproteins. Cholesterol hydroperoxides (Chol-OOH) are the primary products if cholesterol is subjected to attack by reactive oxygen species. In particular, singlet molecular oxygen reacts with cholesterol to yield cholesterol 5α-hydroperoxide as the major hydroperoxide species. Chol-OOH may accumulate in biological systems because of its resistance to glutathione-dependent enzymatic detoxification reactions. Their degradation products (including hydroxycholesterol and 7-ketocholesterol) participate in the pathophysiological functions of oxysterols. Highly reactive cholesterol 5,6-secosterol present in atherosclerotic lesions can be derived from the degradation of cholesterol 5α-hydroperoxide. Chol-OOH themselves may affect the lipid rafts of biomembranes, thereby leading to the modification of signal transduction pathways.
authors.affiliation: Institute of Health Biosciences, University of Tokushima Graduate School, Tokushima, 770-8503, Japan, terao@nutr.med.tokushima-u.ac.jp.
authors.forename: Junji
authors.initials: J
authors.lastname: Terao
mesh_terms: D002784:Cholesterol / Q000031:analogs & derivatives* / Q000737:chemistry / Q000378:metabolism*; D005609:Free Radicals / Q000737:chemistry / Q000378:metabolism; D006861:Hydrogen Peroxide / Q000378:metabolism*; D007653:Ketocholesterols / Q000737:chemistry / Q000378:metabolism; D008081:Liposomes / Q000737:chemistry; D017382:Reactive Oxygen Species / Q000737:chemistry; D015398:Signal Transduction; D026082:Singlet Oxygen / Q000378:metabolism*
chemical_list: D005609:Free Radicals; D007653:Ketocholesterols; D008081:Liposomes; D017382:Reactive Oxygen Species; D026082:Singlet Oxygen; C002843:cholesterol hydroperoxide; D002784:Cholesterol; D006861:Hydrogen Peroxide; C003001:7-ketocholesterol