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A11-positive β-amyloid Oligomer Preparation and Assessment Using Dot Blotting Analysis
Published on: May 22, 2018
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Cobalt(III) Schiff base complexes stabilize non-fibrillar amyloid-β aggregates with reduced toxicity
Kaleigh F Roberts1, Christopher R Brue1, Anna Preston1
1Departments of Chemistry, Molecular Biosciences, Neurobiology, and Radiology, Northwestern University, Evanston, IL 60208, United States.
Journal of Inorganic Biochemistry
|October 15, 2020
Summary
Cobalt(III) Schiff base complexes (Co(III)-sb) were investigated for their effect on amyloid-beta (Aβ) aggregation, a key factor in Alzheimer's disease. Co(III)-sb was found to reduce Aβ cytotoxicity by altering aggregation kinetics.
Area of Science:
- Biochemistry
- Neuroscience
- Materials Science
Background:
- Amyloid-beta (Aβ) aggregation is central to Alzheimer's disease (AD) pathogenesis.
- In vitro Aβ aggregation kinetics serve as a biomarker for disease progression and a target for therapeutics.
Purpose of the Study:
- To investigate the effect of cobalt(III) Schiff base complex (Co(III)-sb) on Aβ aggregation kinetics.
- To determine the mechanism by which Co(III)-sb modulates Aβ aggregation.
- To assess the impact of Co(III)-sb on the cytotoxicity of Aβ aggregates.
Main Methods:
- Utilized Thioflavin T (ThT) fluorescence, circular dichroism (CD) spectroscopy, transmission electron microscopy (TEM), and atomic force microscopy (AFM).
- Applied a mathematical model by Knowles et al. to kinetic data for mechanistic analysis.
- Quantified cytotoxicity of Aβ aggregates formed with and without Co(III)-sb.
Main Results:
- Co(III)-sb decreased Aβ polymerization rate and increased nucleation rate.
- Co(III)-sb promotes rapid stabilization of oligomeric Aβ species, inhibiting fibril elongation.
- Aβ aggregates formed with Co(III)-sb showed reduced cytotoxicity compared to controls.
Conclusions:
- Co(III)-sb effectively modulates Aβ aggregation kinetics, offering a potential therapeutic strategy for Alzheimer's disease.
- The complex stabilizes toxic oligomeric intermediates, reducing overall fibril formation and cytotoxicity.
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