Fibrillar and Nonfibrillar Amyloid Beta Structures Drive Two Modes of Membrane-Mediated Toxicity
- Univ. of New Mexico, Albuquerque, NM (United States); Univ. of Colorado, Colorado Springs, CO (United States)
- Department of Biomedical Engineering, Texas A&M University, College Station, Texas 77843, United States
- Texas A & M Univ., College Station, TX (United States)
- Los Alamos National Lab. (LANL), Los Alamos, NM (United States)
- Univ. of New Mexico, Albuquerque, NM (United States); National Science Foundation (NSF), Alexandria, VA (United States); Los Alamos National Lab. (LANL), Los Alamos, NM (United States)
- Univ. of New Mexico, Albuquerque, NM (United States)
In Alzheimer’s disease, the amyloid-beta peptide (Aβ) is implicated in neuronal toxicity via interactions with the cell membrane. Monomeric Aβ (Aβm) is intrinsically disordered, but it can adopt a range of aggregated conformations with varying toxicities from short fibrillar oligomers (FO), to globular nonfibrillar oligomers (NFO), and full-length amyloid fibrils. NFO is considered to be the most toxic, followed by fibrils, and finally Aβm. To elucidate molecular-level membrane interactions that contribute to their different toxicities, we used liquid surface X-ray scattering and Langmuir trough insertion assays to compare Aβm, FO, and NFO surface activities and interactions with anionic DMPG lipid monolayers at the air/water interface. All Aβ species were highly surface active and rapidly adopted β-sheet rich structures upon adsorption to the air/water interface. Likewise, all Aβ species had affinity for the anionic membrane. Aβm rapidly converted to β-sheet rich assemblies upon binding the membrane, and these aggregated structures of Aβm and FO disrupted hexagonally packed lipid domains and resulted in membrane thinning and instability. In contrast, NFO perturbed membrane structure by extracting lipids from the air/water interface and causing macroscale membrane deformations. Altogether, our results support two models for membrane-mediated Aβ toxicity: fibril-induced reorganization of lipid packing and NFO-induced membrane destabilization and lipid extraction. Here we provide a structural understanding of Aβ neurotoxicity via membrane interactions and aids the effort in understanding early events in Alzheimer’s disease and other neurodegenerative diseases.
- Research Organization:
- Argonne National Laboratory (ANL), Argonne, IL (United States). Advanced Photon Source (APS); Los Alamos National Laboratory (LANL), Los Alamos, NM (United States)
- Sponsoring Organization:
- USDOE Office of Science (SC); National Science Foundation (NSF); Univ. of New Mexico; National Institutes of Health (NIH)
- Grant/Contract Number:
- AC02-06CH11357; CHE-1834750; 1150855; 1605225; 1560058; ASERT-IRACDA-K12-GM088021; UNMCCC-P30-CA118100; UNM-CTSC-UL1-TR001449; NM-INBRE-P20-GM103451; 89233218CNA000001
- OSTI ID:
- 1599452
- Alternate ID(s):
- OSTI ID: 1776772
- Report Number(s):
- LA-UR-21-22944
- Journal Information:
- Langmuir, Vol. 35, Issue 48; ISSN 0743-7463
- Publisher:
- American Chemical SocietyCopyright Statement
- Country of Publication:
- United States
- Language:
- ENGLISH
Web of Science
Facilitation of Gastrointestinal (GI) Tract Microbiome-Derived Lipopolysaccharide (LPS) Entry Into Human Neurons by Amyloid Beta-42 (Aβ42) Peptide
|
journal | December 2019 |
Similar Records
Controlled and Selective Photo-oxidation of Amyloid-β Fibrils by Oligomeric p-Phenylene Ethynylenes
Membrane-mediated fibrillation and toxicity of the tau hexapeptide PHF6