title: Non-fibrillar amyloid-beta peptide reduces NMDA-induced neurotoxicity, but not AMPA-induced neurotoxicity.
abstract: Amyloid-beta peptide (Abeta) is thought to be linked to the pathogenesis of Alzheimer's disease. Recent studies suggest that Abeta has important physiological roles in addition to its pathological roles. We recently demonstrated that Abeta42 protects hippocampal neurons from glutamate-induced neurotoxicity, but the relationship between Abeta42 assemblies and their neuroprotective effects remains largely unknown. In this study, we prepared non-fibrillar and fibrillar Abeta42 based on the results of the thioflavin T assay, Western blot analysis, and atomic force microscopy, and examined the effects of non-fibrillar and fibrillar Abeta42 on glutamate-induced neurotoxicity. Non-fibrillar Abeta42, but not fibrillar Abeta42, protected hippocampal neurons from glutamate-induced neurotoxicity. Furthermore, non-fibrillar Abeta42 decreased both neurotoxicity and increases in the intracellular Ca(2+) concentration induced by N-methyl-d-aspartate (NMDA), but not by alpha-amino-3-hydrozy-5-methyl-4-isoxazole propionic acid (AMPA). Our results suggest that non-fibrillar Abeta42 protects hippocampal neurons from glutamate-induced neurotoxicity through regulation of the NMDA receptor.
authors: Department of Neuroscience for Drug Discovery, Graduate School of Pharmaceutical Sciences, Kyoto University, Kyoto 606-8501, Japan. tniidome@pharm.kyoto-u.ac.jp
authors: Tetsuhiro
authors: T
authors: Niidome
authors: Yasuaki
authors: Y
authors: Goto
authors: Masaru
authors: M
authors: Kato
authors: Pi-Lin
authors: PL
authors: Wang
authors: Saori
authors: S
authors: Goh
authors: Naoki
authors: N
authors: Tanaka
authors: Akinori
authors: A
authors: Akaike
authors: Takeshi
authors: T
authors: Kihara
authors: Hachiro
authors: H
authors: Sugimoto
mesh_terms: D016229:Amyloid beta-Peptides / Q000494:pharmacology / Q000502:physiology*; D000818:Animals; D006624:Hippocampus / Q000166:cytology / Q000187:drug effects / Q000378:metabolism*; D051379:Mice; D008813:Mice, Inbred ICR; D018625:Microscopy, Atomic Force; D016202:N-Methylaspartate / Q000633:toxicity*; D009474:Neurons / Q000187:drug effects / Q000378:metabolism*; D010446:Peptide Fragments / Q000494:pharmacology / Q000502:physiology*; D016194:Receptors, N-Methyl-D-Aspartate / Q000096:biosynthesis; D018350:alpha-Amino-3-hydroxy-5-methyl-4-isoxazolepropionic Acid / Q000633:toxicity*
chemical_list: D016229:Amyloid beta-Peptides; D010446:Peptide Fragments; D016194:Receptors, N-Methyl-D-Aspartate; C075222:amyloid beta-protein (1-42); D016202:N-Methylaspartate; D018350:alpha-Amino-3-hydroxy-5-methyl-4-isoxazolepropionic Acid