title: Antioxidant effect of Ebselen (PZ 51): peroxidase mimetic activity on phospholipid and cholesterol hydroperoxides vs free radical scavenger activity.
abstract: The selenocompound Ebselen (PZ 51) is a potent inhibitor of lipid peroxidation. This antioxidant effect has been previously attributed both to a peroxidase mimetic activity and to a free radical scavenging capability. In the present paper the latter is ruled out by competition kinetic analysis based on the inhibition of carotenoid bleaching by hydroperoxyl radicals. Furthermore, evidence is reported indicating that Ebselen exhibits a peroxidase activity extended to cholesterol and cholesterol ester hydroperoxides, besides phospholipid hydroperoxides. According to this, we propose that the unique mechanism of the antioxidant capacity of Ebselen is the reduction of lipid hydroperoxides present in liposomes or lipoproteins, eventually leading to the prevention of hydroperoxide-dependent peroxidation.
authors.affiliation: Department of Biological Chemistry, Padova, Italy.
authors.forename: M
authors.initials: M
authors.lastname: Maiorino
authors.forename: A
authors.initials: A
authors.lastname: Roveri
authors.forename: F
authors.initials: F
authors.lastname: Ursini
mesh_terms: D000975:Antioxidants / Q000494:pharmacology*; D001393:Azoles / Q000494:pharmacology*; D002784:Cholesterol / Q000031:analogs & derivatives* / Q000378:metabolism; D016166:Free Radical Scavengers; D054833:Isoindoles; D015227:Lipid Peroxidation / Q000187:drug effects; D016566:Organoselenium Compounds / Q000494:pharmacology*; D010544:Peroxidases / Q000378:metabolism*; D010743:Phospholipids / Q000378:metabolism*
chemical_list: D000975:Antioxidants; D001393:Azoles; D016166:Free Radical Scavengers; D054833:Isoindoles; D016566:Organoselenium Compounds; D010743:Phospholipids; C042986:ebselen; C002843:cholesterol hydroperoxide; D002784:Cholesterol; D010544:Peroxidases