Related Experiment Video

Updated: Jun 3, 2025

Analysis of β-Amyloid-induced Abnormalities on Fibrin Clot Structure by Spectroscopy and Scanning Electron Microscopy
06:27

Analysis of β-Amyloid-induced Abnormalities on Fibrin Clot Structure by Spectroscopy and Scanning Electron Microscopy

Published on: November 30, 2018

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Amyloid beta (Aβ) fibrillation kinetics and its impact on membrane polarity

Arun Ajaikumar1, Nozomi Morishita Watanabe1, Keishi Suga2

  • 1Division of Chemical Engineering, Graduate School of Engineering Science, Osaka University, 1-3 Machikaneyamacho, Toyonaka, Osaka, 560-8531, Japan.

Journal of Bioenergetics and Biomembranes
|January 6, 2025
PubMed

Insights

Amyloid beta (Aβ) peptide fibrillation accelerates on fluid lipid membranes, causing dehydration and impacting deeper membrane regions. This research offers insights into Aβ-induced membrane damage relevant to Alzheimer's disease.

Area of Science:

  • Biochemistry
  • Neuroscience
  • Materials Science

Background:

  • Amyloid beta (Aβ) peptide fibrillation is linked to neurodegenerative diseases like Alzheimer's.
  • Lipid membranes play a crucial role in modulating Aβ aggregation and its pathological effects.

Purpose of the Study:

  • To investigate how different lipid membrane compositions influence Aβ fibrillation kinetics and membrane damage.
  • To analyze the impact of Aβ aggregation on membrane hydration and polarity.

Main Methods:

  • Utilized liposomes as a model lipid membrane system.
  • Monitored Aβ fibrillation kinetics.
  • Analyzed membrane polarity and hydration using Laurdan fluorescence spectroscopy and deconvolution analysis.

Main Results:

  • Aβ fibrillation kinetics were faster on more fluid membranes compared to solid membranes.
  • Membrane dehydration occurred as fibrillation progressed.
  • Aβ aggregation induced subtle but significant changes in deeper membrane regions' polarity.

Conclusions:

  • Membrane fluidity significantly affects Aβ fibrillation rates.
  • Aβ aggregation alters membrane hydration and polarity, affecting both surface and interior regions.
  • Findings contribute to understanding Aβ-induced membrane damage in neurodegeneration.
Keywords:
Amyloid-βBrainFibrillationGeneralized PolarityLaurdanNeuronPolarity

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