title: Elevated plasma cholesterol does not affect brain Abeta in mice lacking the low-density lipoprotein receptor.
abstract: Epidemiological studies support an association between vascular risk factors, including hypercholesterolemia, and Alzheimer's disease (AD). Recently, there has been much interest in the possibility that hypercholesterolemia might directly promote beta-amyloid (Abeta) production. Indeed, in vitro studies have shown that increasing cellular cholesterol levels enhances Abeta production. However, studies in AD transgenic mouse models have not consistently found that elevated plasma cholesterol leads to increased Abeta production or deposition in vivo. In this study, we determined whether elevated peripheral cholesterol influences Abeta production in mice with a null mutation of the low-density lipoprotein receptor (LDLR). We show that dramatically elevated plasma cholesterol levels, whether induced by high cholesterol, high fat, or high fat/high cholesterol diets, did not affect either levels of brain Abeta40, Abeta42, or APP, or the Abeta42/40 or APP-CTF/APP ratios, nor substantially alter brain cholesterol levels. ApoE protein levels in brain were, however, elevated, in LDLR-/- mice by post-transcriptional mechanisms. Collectively, these studies argue that plasma cholesterol levels do not normally regulate production of brain Abeta.
authors.affiliation: Department of Psychiatry, Mount Sinai School of Medicine, New York, NY 10029, USA.
authors.forename: Gregory A
authors.initials: GA
authors.lastname: Elder
authors.forename: Julie Y
authors.initials: JY
authors.lastname: Cho
authors.forename: Daniel F
authors.initials: DF
authors.lastname: English
authors.forename: Sonia
authors.initials: S
authors.lastname: Franciosi
authors.forename: James
authors.initials: J
authors.lastname: Schmeidler
authors.forename: Miguel A Gama
authors.initials: MA
authors.lastname: Sosa
authors.forename: Rita De
authors.initials: RD
authors.lastname: Gasperi
authors.forename: Edward A
authors.initials: EA
authors.lastname: Fisher
authors.forename: Paul M
authors.initials: PM
authors.lastname: Mathews
authors.forename: Vahram
authors.initials: V
authors.lastname: Haroutunian
authors.forename: Joseph D
authors.initials: JD
authors.lastname: Buxbaum
mesh_terms: D016229:Amyloid beta-Peptides / Q000378:metabolism*; D000704:Analysis of Variance; D000818:Animals; D001057:Apolipoproteins E / Q000235:genetics / Q000378:metabolism; D001921:Brain / Q000378:metabolism*; D002784:Cholesterol / Q000097:blood*; D015870:Gene Expression / Q000235:genetics; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D018345:Mice, Knockout; D010446:Peptide Fragments / Q000378:metabolism*; D012333:RNA, Messenger / Q000378:metabolism; D011973:Receptors, LDL / Q000172:deficiency*; D020133:Reverse Transcriptase Polymerase Chain Reaction
chemical_list: D016229:Amyloid beta-Peptides; D001057:Apolipoproteins E; D010446:Peptide Fragments; D012333:RNA, Messenger; D011973:Receptors, LDL; C078592:amyloid beta-protein (1-40); C075222:amyloid beta-protein (1-42); D002784:Cholesterol