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Updated: May 13, 2026

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A11-positive β-amyloid Oligomer Preparation and Assessment Using Dot Blotting Analysis
Published on: May 22, 2018
Cellular polyamines promote amyloid-beta (Aβ) peptide fibrillation and modulate the aggregation pathways
Jinghui Luo1, Chien-Hung Yu, Huixin Yu
1Gorlaeus Laboratory, Leiden Institute of Chemistry, Leiden University, 2300RA Leiden, The Netherlands.
ACS Chemical Neuroscience
|March 21, 2013
Summary
Cellular polyamines like spermine accelerate amyloid-beta (Aβ) peptide aggregation, a key process in Alzheimer's disease. These molecules influence aggregation pathways, offering potential therapeutic targets.
Area of Science:
- Biochemistry
- Neuroscience
- Molecular Biology
Background:
- Cellular polyamines (spermine, spermidine, putrescine) are linked to cell growth, gene regulation, and Alzheimer's disease.
- Amyloid-beta (Aβ) peptide aggregation into fibrils is a hallmark of Alzheimer's pathology.
Purpose of the Study:
- To investigate the in vitro effects of polyamines on amyloid-beta (Aβ) peptide aggregation.
- To elucidate how polyamines modulate Aβ aggregation pathways and structures.
Main Methods:
- In vitro spectroscopy (NMR, CD, ThT kinetics)
- Atomic Force Microscopy (AFM) imaging
Main Results:
- Polyamines (spermine, spermidine, putrescine) bind similarly to monomeric Aβ(1-40) and promote fibril formation.
- Low polyamine concentrations significantly reduce Aβ aggregation lag and transition times.
- Polyamines induce distinct Aβ aggregation pathways and aggregate morphologies.
Conclusions:
- Polyamines modulate Aβ aggregation, influencing pathway and structure.
- Targeting polyamine-modulated Aβ aggregation may offer a therapeutic strategy for Alzheimer's disease.
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