Oxysterol regulators of 3-hydroxy-3-methylglutaryl-CoA reductase in liver. Effect of dietary cholesterol.

作者: S E Saucier , A A Kandutsch , A K Gayen , D K Swahn , T A Spencer

DOI: 10.1016/S0021-9258(18)83510-4

关键词:

摘要: Hepatic regulatory oxysterols were analyzed to determine which present in livers of mice fed a cholesterol-free diet and whether repression 3-hydroxy-3-methylglutaryl-CoA reductase following cholesterol feeding was accompanied by an increase one or more oxysterols. Analysis free esterified sterols from resulted the identification quantitation six oxysterols: 24-hydroxycholesterol, 25-hydroxycholesterol, 26-hydroxycholesterol, 7 α-hydroxycholesterol, β-hydroxycholesterol, 7-ketocholesterol. Following addition for 1 2 nights, hepatic activity declined levels oxysterols, especially those side-chain-hydroxylated sterols, increased. Total repressor units attributable identified increased 2.5- 6-fold after respectively, feeding. The amounts 24-, 25-, 26-hydroxycholesterol also increased, with 24-hydroxycholesterol being greatest. predominantly 24S epimer 25R epimer, indicating enzymatic catalysis their formation. observed correlation between cholesterol-fed is consistent hypothesis that intracellular oxysterol metabolites regulate level reductase.

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