%0 Journal Article %T Antioxidant Supplements Improve Profiles of Hepatic Oxysterols and Plasma Lipids in Butter-fed Hamsters %A Johanne Poirier %A Kevin A. Cockell %A W.M. Nimal Ratnayake %A Kylie A. Scoggan %A Nick Hidiroglou %A Claude Gagnon %A H¨¦l¨¨ne Rocheleau %A Heidi Gruber %A Philip Griffin %A Ren¨¦ Mad¨¨re %A Keith Trick and Stan Kubow %J Nutrition and Metabolic Insights %D 2012 %I %R 10.4137/NMI.S3911 %X Hypercholesterolemic diets are associated with oxidative stress that may contribute to hypercholesterolemia by adversely affecting enzymatically-generated oxysterols involved in cholesterol homeostasis. An experiment was conducted to examine whether the cholesterol-lowering effects of the antioxidants selenium and ¦Á-tocopherol were related to hepatic oxysterol concentrations. Four groups of male Syrian hamsters (n = 7¨C8) were fed high cholesterol and saturated fat (0.46% cholesterol, 14.3% fat) hypercholesterolemic semi-purified diets: 1) Control; 2) Control + ¦Á-tocopherol (67 IU all-racemic-¦Á-tocopheryl-acetate/kg diet); 3) Control + selenium (3.4 mg selenate/kg diet); and 4) Control + ¦Á-tocopherol + selenium. Antioxidant supplementation was associated with lowered plasma cholesterol concentrations, decreased tissue lipid peroxidation and higher hepatic oxysterol concentrations. A second experiment examined the effect of graded selenium doses (0.15, 0.85, 1.7 and 3.4 mg selenate/kg diet) on mRNA expression of the oxysterol-generating enzyme, hepatic 27-hydroxylase (CYP27A1, EC 1.14.13.15), in hamsters (n = 8¨C9) fed the hypercholesterolemic diets. Supplementation of selenium at 3.4 mg selenate/kg diet was not associated with increased hepatic 27-hydroxylase mRNA. In conclusion, the cholesterol lowering effects of selenium and ¦Á-tocopherol were associated with increased hepatic enzymatically generated oxysterol concentrations, which appears to be mediated via improved antioxidant status rather than increased enzymatic production. %U http://www.la-press.com/antioxidant-supplements-improve-profiles-of-hepatic-oxysterols-and-pla-article-a1849