Membrane-disordering effects of beta-amyloid peptides

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Interactions with and Membrane Permeabilization of Brain Mitochondria by Amyloid Fibrils
00:15

Interactions with and Membrane Permeabilization of Brain Mitochondria by Amyloid Fibrils

Published on: September 28, 2019

W E Müller1, C Kirsch, G P Eckert

  • 1Department of Pharmacology, Biocenter University of Frankfurt, Marie-Curie Strasse 9, D-60439 Frankfurt, Germany. PharmacolNat@em.uni-frankfurt.de

Biochemical Society Transactions
|August 11, 2001
PubMed

Insights

Beta-amyloid (Abeta) peptides, found in Alzheimer's disease (AD) plaques, alter cell membrane fluidity. This disruption of the acyl-chain layer may be an early step in AD pathogenesis.

Area of Science:

  • Neuroscience
  • Biochemistry
  • Cell Biology

Background:

  • Beta-amyloid (Abeta) protein aggregates form senile plaques and cerebrovascular deposits in Alzheimer's disease (AD).
  • The precise mechanism linking Abeta to AD-induced neurodegeneration remains unclear.

Purpose of the Study:

  • To investigate the effects of Abeta on cell membrane fluidity.
  • To determine if Abeta's interaction with membranes is an early biological event in AD.

Main Methods:

  • Utilized fluorescent probes to measure changes in cell membrane fluidity.
  • Examined membrane fractions from various tissues and species, including human.

Main Results:

  • Low concentrations of Abeta significantly altered cell membrane fluidity across different tissues and species.
  • Abeta peptides specifically disturbed the acyl-chain layer of cell membranes.
  • The polar head region of the phospholipid bilayer and membrane proteins were less affected.

Conclusions:

  • Abeta's alteration of cell membrane fluidity, particularly the acyl-chain layer, is a significant biological effect.
  • This membrane perturbation may represent an initial step in the pathogenesis of Alzheimer's disease.

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