The role of oxysterols in cholesterol homeostasis.
Cholesterol biosynthesis is regulated by transcription factors named steroid regulatory element-binding proteins. A newly discovered transcription factor, LXR, regulates the catabolic degradation of cholesterol by activation of the gene controlling cholesterol 7 alpha-hydroxylase, the rate-limiting enzyme in the formation of bile acids. Excessive dietary cholesterol leads to increased oxysterol formation. Oxysterol binds to LXR and thereby induces transcription of cholesterol 7 alpha-hydroxylase, thus increasing the removal of cholesterol as bile acids.
Wolf
G
G
Department of Nutritional Sciences, University of California, Berkeley 94720-3104, USA.
D000818:Animals; D001647:Bile Acids and Salts / Q000096:biosynthesis; D002784:Cholesterol / Q000096:biosynthesis*; D002790:Cholesterol 7-alpha-Hydroxylase / Q000235:genetics / Q000502:physiology*; D002791:Cholesterol, Dietary / Q000378:metabolism; D004268:DNA-Binding Proteins; D006706:Homeostasis; D006801:Humans; D000071518:Liver X Receptors; D051379:Mice; D018345:Mice, Knockout; D057093:Orphan Nuclear Receptors; D018160:Receptors, Cytoplasmic and Nuclear / Q000378:metabolism*; D013261:Sterols / Q000378:metabolism; D014157:Transcription Factors / Q000502:physiology
D001647:Bile Acids and Salts; D002791:Cholesterol, Dietary; D004268:DNA-Binding Proteins; D000071518:Liver X Receptors; D057093:Orphan Nuclear Receptors; D018160:Receptors, Cytoplasmic and Nuclear; D013261:Sterols; D014157:Transcription Factors; D002784:Cholesterol; D002790:Cholesterol 7-alpha-Hydroxylase