Intrinsic visible emission of amyloid-β oligomers: a potential tool for early alzheimer's diagnosis

Alzheimer's disease (AD) is a major public health challenge, with its onset occurring years before symptoms appear. Soluble amyloid-β (Aβ) oligomers are key species in AD pathogenesis and diagnosis, highlighting the need for early detection. This study investigates the intrinsic fluorescence of Aβ(1...

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Bibliographic Details
Authors: Novo, Mercedes; Illodo Brea, Sara; Seijas Cerceda, Jesús; Moraes, Stella Hernández Faria De; Rodríguez-Prieto, Flor; Al-Soufi, Wajih
Format: Article
Publication date:2025
Country:España
Institution:Universidad de Santiago de Compostela (USC)
Repository:Minerva. Repositorio Institucional de la Universidad de Santiago de Compostela
Language:English
OAI Identifier:oai:minerva.usc.gal:10347/43532
Online Access:https://hdl.handle.net/10347/43532
Access Level:Open access
Keyword:Alzheimer’s disease
Soluble amyloid-b (Ab) oligomers
Pathogenesis
diagnosis
Description
Summary:Alzheimer's disease (AD) is a major public health challenge, with its onset occurring years before symptoms appear. Soluble amyloid-β (Aβ) oligomers are key species in AD pathogenesis and diagnosis, highlighting the need for early detection. This study investigates the intrinsic fluorescence of Aβ(1–40) (Aβ40) as a label-free approach to detecting early-stage oligomers. Aβ40 exhibits autofluorescence dominated by tyrosine emission, which undergoes a strong blue shift and quenching during oligomerization. Additionally, aggregation-induced emission (AIE) in the visible spectral region emerges, correlating with Aβ oligomer concentration and providing a means to detect and quantify oligomers. At the critical aggregation concentrations cac1 = 0.5 μM and cac2 = 19 μM, distinct aggregation behaviours are observed. By employing steady-state fluorescence spectroscopy, a widely accessible technique, these findings establish a direct link between early Aβ aggregation and intrinsic fluorescence changes. This approach eliminates the need for extrinsic probes, simplifying experimental procedures and reducing artefacts. Although further studies are required to develop a robust quantitative correlation for potential diagnostic applications, Aβ autofluorescence represents a promising strategy for investigating early aggregation processes in the context of AD