title: ToF-SIMS analysis of amyloid beta aggregation on different lipid membranes.
abstract: Amyloid beta (Aβ) peptides are considered to be strongly related to Alzheimer's disease. Aβ peptides form a β-sheet structure on hard lipid membranes and it would aggregate to form amyloid fibrils, which are toxic to cells. However, the aggregation mechanism of Aβ is not fully understood. To evaluate the influence of the lipid membrane condition for Aβ aggregation, the adsorption forms of Aβ (1-40) on mixture membranes of lipid 1,2-dimyristoyl-sn-glycero-3-phosphocholine (DMPC) and cholesterol β-d-glucoside (β-CG) were investigated by time-of-flight secondary ion mass spectrometry. As a result, Aβ adsorbed along the localized DMPC lipid on the mixture lipid membranes, whereas it was adsorbed homogeneously on the pure DMPC and β-CG membranes. Moreover, amino acid fragments that mainly existed in the n-terminal of Aβ (1-40) peptide were strongly detected on the localized DMPC region. These results suggested that the Aβ was adsorbed along the localized DMPC lipid with a characteristic orientation. These findings suggest that the hardness of the membrane is very sensitive to coexisting materials and that surface hardness is important for aggregation of Aβ.
authors.affiliation: Department of Materials and Life Science, Seikei University, 3-3-1, Kichijyoji-kitamachi, Musashino, Tokyo 180-8633, Japan.
authors.forename: Yuta
authors.initials: Y
authors.lastname: Yokoyama
authors.affiliation: Department of Materials and Life Science, Seikei University, 3-3-1, Kichijyoji-kitamachi, Musashino, Tokyo 180-8633, Japan.
authors.forename: Satoka
authors.initials: S
authors.lastname: Aoyagi
authors.affiliation: Faculty of Environmental Science and Technology, Okayama University, 3-1-1 Tsushima-naka, Kita-ku, Okayama 700-8530, Japan.
authors.forename: Toshinori
authors.initials: T
authors.lastname: Shimanouchi
authors.affiliation: Faculty of Environmental Science and Technology, Okayama University, 3-1-1 Tsushima-naka, Kita-ku, Okayama 700-8530, Japan.
authors.forename: Miki
authors.initials: M
authors.lastname: Iwamura
authors.affiliation: National Institute for Materials Science, Materials Analysis Station, 1-2-1, Sengen, Tsukuba, Ibaraki 305-0047, Japan.
authors.forename: Hideo
authors.initials: H
authors.lastname: Iwai
mesh_terms: D016229:Amyloid beta-Peptides / Q000032:analysis*; D008566:Membranes / Q000737:chemistry*; D066329:Protein Aggregates; D018629:Spectrometry, Mass, Secondary Ion / Q000379:methods*
chemical_list: D016229:Amyloid beta-Peptides; D066329:Protein Aggregates