Effective screen for amyloid β aggregation inhibitor using amyloid β-conjugated gold nanoparticles

Area of Science:

• Biochemistry
• Nanotechnology
• Neuroscience

Background:

• Alzheimer's disease (AD) pathogenesis involves abnormal amyloid-beta (Aβ) aggregation.
• Early detection of Aβ aggregates is challenging, hindering AD biomarker and drug development.

Purpose of the Study:

• To develop a novel method for visualizing Aβ42 aggregation using gold nanoparticles (AuNPs).
• To establish a screen for validating Aβ aggregation inhibitors.
• To explore potential diagnostic and prognostic tools for neurodegenerative diseases.

Main Methods:

• Conjugation of amyloid-beta 42 (Aβ42) peptide to gold nanoparticles (AuNPs).
• Visualization of Aβ42 aggregation via AuNP precipitation induced by Aβ42 aggregation.
• Quantification using optical density and thioflavin T binding assay.
• Transmission electron microscopy (TEM) for structural analysis.
• Testing transthyretin as an Aβ aggregation inhibitor.
• Analysis of Aβ42-conjugated AuNPs in blood-driven serum.

Main Results:

• Aβ42 aggregation induced AuNP precipitation, visualized by TEM.
• Optical density and thioflavin T assays quantified the precipitation.
• Transthyretin inhibited Aβ42 aggregation and AuNP precipitation.
• Differentiated aggregation patterns were observed between normal and AD serum samples.

Conclusions:

• AuNP-Aβ42 precipitation serves as a visual indicator of Aβ42 aggregation.
• This method can screen Aβ aggregation inhibitors and potentially diagnose AD.
• The findings suggest a breakthrough for diagnostic and prognostic tools in protein aggregation diseases.