Changes in lipid membranes may trigger amyloid toxicity in Alzheimer's disease

PLoS One. 2017 Aug 2;12(8):e0182194. doi: 10.1371/journal.pone.0182194. eCollection 2017.

Abstract

Amyloid-beta peptides (Aβ), implicated in Alzheimer's disease (AD), interact with the cellular membrane and induce amyloid toxicity. The composition of cellular membranes changes in aging and AD. We designed multi-component lipid models to mimic healthy and diseased states of the neuronal membrane. Using atomic force microscopy (AFM), Kelvin probe force microscopy (KPFM) and black lipid membrane (BLM) techniques, we demonstrated that these model membranes differ in their nanoscale structure and physical properties, and interact differently with Aβ1-42. Based on our data, we propose a new hypothesis that changes in lipid membrane due to aging and AD may trigger amyloid toxicity through electrostatic mechanisms, similar to the accepted mechanism of antimicrobial peptide action. Understanding the role of the membrane changes as a key activating amyloid toxicity may aid in the development of a new avenue for the prevention and treatment of AD.

MeSH terms

  • Aging / metabolism
  • Alzheimer Disease / metabolism*
  • Alzheimer Disease / pathology*
  • Amyloid beta-Peptides / metabolism*
  • Cell Membrane / metabolism*
  • Humans
  • Membrane Lipids / metabolism
  • Microscopy, Atomic Force
  • Neurons / pathology*

Substances

  • Amyloid beta-Peptides
  • Membrane Lipids

Grants and funding

This work was supported by a Natural Science and Engineering Council of Canada (NSERC) grant to ZL, Heart and Stroke Foundation of Canada grant and American Heart Association grant to EP, an NSERC Canada Graduate Scholarship and WIN Fellowship to ED, and an NSERC Undergraduate Student Research Award to KH.