Protection of superoxide-induced cholesterol oxidation by antioxidants in protic conditions.
It was found in previous experiments that superoxide in the presence of added hydrogen peroxide in protic conditions produces oxysterols. The oxysterols formed under these conditions were 7beta-ketocholesterol, 7alpha-hydroxycholesterol and 7beta-hydroxycholesterol. In the present experiments, the inhibitory effects of three antioxidants, alpha-tocopherol (alpha-T), butylated hydroxyanisole (BHA) and butylated hydroxytoluene (BHT), on the oxidation of cholesterol in the presence of superoxide anion, water and hydrogen peroxide were investigated. It was found that BHA had the highest antioxidant activity on cholesterol oxidation, followed by alpha-T and BHT. The presence of antioxidants markedly retarded the formation of 7-ketocholesterol. The formation of 7beta-hydroxycholesterol or 7alpha-hydroxycholesterol was also reduced, but to a lesser degree.
Csallany
A Saari
AS
Department of Food Science and Nutrition, University of Minnesota, St Paul 55108, USA.
Hee-Lee
Joo
J
Shoeman
D W
DW
D000975:Antioxidants / Q000494:pharmacology*; D002784:Cholesterol / Q000378:metabolism*; D002851:Chromatography, High Pressure Liquid; D004305:Dose-Response Relationship, Drug; D006801:Humans; D006861:Hydrogen Peroxide / Q000494:pharmacology; D006888:Hydroxycholesterols / Q000378:metabolism; D007653:Ketocholesterols / Q000096:biosynthesis; D015227:Lipid Peroxidation / Q000187:drug effects*; D010084:Oxidation-Reduction / Q000187:drug effects; D013481:Superoxides / Q000037:antagonists & inhibitors / Q000494:pharmacology*
D000975:Antioxidants; D006888:Hydroxycholesterols; D007653:Ketocholesterols; D013481:Superoxides; D002784:Cholesterol; D006861:Hydrogen Peroxide; C003001:7-ketocholesterol