Regulation of absorption and ABC1-mediated efflux of cholesterol by RXR heterodimers.
Several nuclear hormone receptors involved in lipid metabolism form obligate heterodimers with retinoid X receptors (RXRs) and are activated by RXR agonists such as rexinoids. Animals treated with rexinoids exhibited marked changes in cholesterol balance, including inhibition of cholesterol absorption and repressed bile acid synthesis. Studies with receptor-selective agonists revealed that oxysterol receptors (LXRs) and the bile acid receptor (FXR) are the RXR heterodimeric partners that mediate these effects by regulating expression of the reverse cholesterol transporter, ABC1, and the rate-limiting enzyme of bile acid synthesis, CYP7A1, respectively. Thus, these RXR heterodimers serve as key regulators of cholesterol homeostasis by governing reverse cholesterol transport from peripheral tissues, bile acid synthesis in liver, and cholesterol absorption in intestine.
Repa
J J
JJ
Howard Hughes Medical Institute and Department of Pharmacology, University of Texas Southwestern Medical Center, 5323 Harry Hines Boulevard, Dallas, TX 75390-9050, USA.
Turley
S D
SD
Lobaccaro
J A
JA
Medina
J
J
Li
L
L
Lustig
K
K
Shan
B
B
Heyman
R A
RA
Dietschy
J M
JM
Mangelsdorf
D J
DJ
D064286:ATP Binding Cassette Transporter 1; D018528:ATP-Binding Cassette Transporters / Q000235:genetics / Q000378:metabolism*; D000818:Animals; D001647:Bile Acids and Salts / Q000096:biosynthesis; D001692:Biological Transport / Q000187:drug effects; D002784:Cholesterol / Q000378:metabolism*; D002790:Cholesterol 7-alpha-Hydroxylase / Q000378:metabolism; D002791:Cholesterol, Dietary / Q000008:administration & dosage; D006224:Cricetinae; D004268:DNA-Binding Proteins / Q000378:metabolism; D019281:Dimerization; D005786:Gene Expression Regulation / Q000187:drug effects; D006023:Glycoproteins / Q000235:genetics / Q000378:metabolism*; D006706:Homeostasis / Q000187:drug effects; D007408:Intestinal Absorption / Q000187:drug effects*; D007421:Intestine, Small / Q000378:metabolism*; D008024:Ligands; D008099:Liver / Q000378:metabolism*; D000071518:Liver X Receptors; D017737:Macrophages, Peritoneal / Q000378:metabolism; D008297:Male; D008647:Mesocricetus; D051379:Mice; D008810:Mice, Inbred C57BL; D018345:Mice, Knockout; D057093:Orphan Nuclear Receptors; D018160:Receptors, Cytoplasmic and Nuclear; D018168:Receptors, Retinoic Acid / Q000819:agonists / Q000235:genetics / Q000378:metabolism*; D011988:Receptors, Thyroid Hormone / Q000819:agonists / Q000235:genetics / Q000378:metabolism; D047488:Retinoid X Receptors; D014157:Transcription Factors / Q000819:agonists / Q000378:metabolism*; D000099150:Receptor, Farnesoid X-Activated
D064286:ATP Binding Cassette Transporter 1; D018528:ATP-Binding Cassette Transporters; D001647:Bile Acids and Salts; D002784:Cholesterol; D002790:Cholesterol 7-alpha-Hydroxylase; D002791:Cholesterol, Dietary; D004268:DNA-Binding Proteins; D006023:Glycoproteins; D008024:Ligands; D000071518:Liver X Receptors; D057093:Orphan Nuclear Receptors; D018160:Receptors, Cytoplasmic and Nuclear; D018168:Receptors, Retinoic Acid; D011988:Receptors, Thyroid Hormone; D047488:Retinoid X Receptors; D014157:Transcription Factors; D000099150:Receptor, Farnesoid X-Activated