title: Regulation of cholesterol homeostasis by the liver X receptors in the central nervous system.
abstract: The nuclear oxysterol receptors liver X receptor-alpha [LXRalpha (NR1H3)] and LXRbeta (NR1H2) coordinately regulate genes involved in cholesterol homeostasis. Although both LXR subtypes are expressed in the brain, their roles in this tissue remain largely unexplored. In this report, we show that LXR agonists have marked effects on gene expression in murine brain tissue both in vitro and in vivo. In primary astrocyte cultures, LXR agonists regulated several established LXR target genes, including ATP binding cassette transporter A1, and enhanced cholesterol efflux. In contrast, little or no effect on gene expression or cholesterol efflux was detected in primary neuronal cultures. Treatment of mice with a selective LXR agonist resulted in the induction of several LXR target genes related to cholesterol homeostasis in the cerebellum and hippocampus. These data provide the first evidence that the LXRs regulate cholesterol homeostasis in the central nervous system. Because dysregulation of cholesterol balance is implicated in central nervous system diseases such as Alzheimer's and Niemann-Pick disease, pharmacological manipulation of the LXRs may prove beneficial in the treatment of these disorders.
authors.affiliation: GlaxoSmithKline Research and Development, Research Triangle Park, North Carolina 27709, USA.
authors.forename: Karl D
authors.initials: KD
authors.lastname: Whitney
authors.forename: Michael A
authors.initials: MA
authors.lastname: Watson
authors.forename: Jon L
authors.initials: JL
authors.lastname: Collins
authors.forename: William G
authors.initials: WG
authors.lastname: Benson
authors.forename: Tammy M
authors.initials: TM
authors.lastname: Stone
authors.forename: Mary Jo
authors.initials: MJ
authors.lastname: Numerick
authors.forename: Timothy K
authors.initials: TK
authors.lastname: Tippin
authors.forename: Joan G
authors.initials: JG
authors.lastname: Wilson
authors.forename: Deborah A
authors.initials: DA
authors.lastname: Winegar
authors.forename: Steven A
authors.initials: SA
authors.lastname: Kliewer
mesh_terms: D000818:Animals; D002460:Cell Line; D002490:Central Nervous System / Q000378:metabolism*; D002784:Cholesterol / Q000378:metabolism*; D005786:Gene Expression Regulation; D006706:Homeostasis; D017403:In Situ Hybridization; D051379:Mice; D009928:Organ Specificity; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism
chemical_list: D012333:RNA, Messenger; D002784:Cholesterol