title: Human prefoldin inhibits amyloid-β (Aβ) fibrillation and contributes to formation of nontoxic Aβ aggregates.
abstract: Amyloid-β (Aβ) peptides represent key players in the pathogenesis of Alzheimer's disease (AD), and mounting evidence indicates that soluble Aβ oligomers mediate the toxicity. Prefoldin (PFD) is a molecular chaperone that prevents aggregation of misfolded proteins. Here we investigated the role of PFD in Aβ aggregation. First, we demonstrated that PFD is expressed in mouse brain by Western blotting and immunohistochemistry and found that PFD is upregulated in AD model APP23 transgenic mice. Then we investigated the effect of recombinant human PFD (hPFD) on Aβ(1-42) aggregation in vitro and found that hPFD inhibited Aβ fibrillation and induced formation of soluble Aβ oligomers. Interestingly, cell viability measurements using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay showed that Aβ oligomers formed by hPFD were 30-40% less toxic to cultured rat pheochromocytoma (PC12) cells or primary cortical neurons from embryonic C57BL/6CrSlc mice than previously reported Aβ oligomers (formed by archaeal PFD) and Aβ fibrils (p < 0.001). Thioflavin T measurements and immunoblotting indicated different structural properties for the different Aβ oligomers. Our findings show a relation between cytotoxicity of Aβ oligomers and structure and suggest a possible protective role of PFD in AD.
authors.affiliation: Bioengineering Laboratory, RIKEN , 2-1 Hirosawa, Wako, Saitama 351-0198, Japan.
authors.forename: Karin Margareta
authors.initials: KM
authors.lastname: Sörgjerd
authors.forename: Tamotsu
authors.initials: T
authors.lastname: Zako
authors.forename: Masafumi
authors.initials: M
authors.lastname: Sakono
authors.forename: Peter C
authors.initials: PC
authors.lastname: Stirling
authors.forename: Michel R
authors.initials: MR
authors.lastname: Leroux
authors.forename: Takashi
authors.initials: T
authors.lastname: Saito
authors.forename: Per
authors.initials: P
authors.lastname: Nilsson
authors.forename: Misaki
authors.initials: M
authors.lastname: Sekimoto
authors.forename: Takaomi C
authors.initials: TC
authors.lastname: Saido
authors.forename: Mizuo
authors.initials: M
authors.lastname: Maeda
mesh_terms: D000544:Alzheimer Disease / Q000378:metabolism; D016229:Amyloid beta-Peptides / Q000037:antagonists & inhibitors* / Q000378:metabolism; D000818:Animals; D002470:Cell Survival; D006801:Humans; D051379:Mice; D008810:Mice, Inbred C57BL; D008822:Mice, Transgenic; D046529:Microscopy, Electron, Transmission; D018832:Molecular Chaperones / Q000737:chemistry / Q000378:metabolism*; D009474:Neurons / Q000378:metabolism; D010446:Peptide Fragments / Q000037:antagonists & inhibitors* / Q000378:metabolism
chemical_list: D016229:Amyloid beta-Peptides; D018832:Molecular Chaperones; D010446:Peptide Fragments; C075222:amyloid beta-protein (1-42); C112806:prefoldin