title: Environmental enrichment reduces Abeta levels and amyloid deposition in transgenic mice.
abstract: Cerebral deposition of beta-amyloid (Abeta) peptides is an invariant pathological hallmark in brains of patients with Alzheimer's disease (AD) and transgenic mice coexpressing familial AD-linked APP and PS1 variants. We now report that exposure of transgenic mice to an "enriched environment" results in pronounced reductions in cerebral Abeta levels and amyloid deposits, compared to animals raised under "standard housing" conditions. The enzymatic activity of an Abeta-degrading endopeptidase, neprilysin, is elevated in the brains of "enriched" mice and inversely correlated with amyloid burden. Moreover, DNA microarray analysis revealed selective upregulation in levels of transcripts encoded by genes associated with learning and memory, vasculogenesis, neurogenesis, cell survival pathways, Abeta sequestration, and prostaglandin synthesis. These studies provide evidence that environmental enrichment leads to reductions in steady-state levels of cerebral Abeta peptides and amyloid deposition and selective upregulation in levels of specific transcripts in brains of transgenic mice.
authors.affiliation: Department of Neurobiology, Pharmacology, and Physiology, University of Chicago, Chicago, IL 60637, USA.
authors.forename: Orly
authors.initials: O
authors.lastname: Lazarov
authors.forename: John
authors.initials: J
authors.lastname: Robinson
authors.forename: Ya-Ping
authors.initials: YP
authors.lastname: Tang
authors.forename: Ilana S
authors.initials: IS
authors.lastname: Hairston
authors.forename: Zeljka
authors.initials: Z
authors.lastname: Korade-Mirnics
authors.forename: Virginia M-Y
authors.initials: VM
authors.lastname: Lee
authors.forename: Louis B
authors.initials: LB
authors.lastname: Hersh
authors.forename: Robert M
authors.initials: RM
authors.lastname: Sapolsky
authors.forename: Karoly
authors.initials: K
authors.lastname: Mirnics
authors.forename: Sangram S
authors.initials: SS
authors.lastname: Sisodia
mesh_terms: D000544:Alzheimer Disease / Q000235:genetics / Q000378:metabolism / Q000517:prevention & control*; D016229:Amyloid beta-Peptides / Q000378:metabolism*; D016564:Amyloid beta-Protein Precursor / Q000378:metabolism; D000818:Animals; D002540:Cerebral Cortex / Q000378:metabolism* / Q000473:pathology / Q000503:physiopathology; D004195:Disease Models, Animal; D015536:Down-Regulation / Q000502:physiology; D004777:Environment; D005106:Exploratory Behavior / Q000502:physiology*; D005786:Gene Expression Regulation / Q000502:physiology; D008297:Male; D008565:Membrane Proteins / Q000378:metabolism; D051379:Mice; D008822:Mice, Transgenic; D015260:Neprilysin / Q000378:metabolism; D009419:Nerve Tissue Proteins / Q000235:genetics / Q000378:metabolism; D020411:Oligonucleotide Array Sequence Analysis; D058225:Plaque, Amyloid / Q000235:genetics / Q000378:metabolism*; D053764:Presenilin-1; D015854:Up-Regulation / Q000502:physiology
chemical_list: D016229:Amyloid beta-Peptides; D016564:Amyloid beta-Protein Precursor; D008565:Membrane Proteins; D009419:Nerve Tissue Proteins; D053764:Presenilin-1; D015260:Neprilysin