Validation of Fucoxanthin from Microalgae Phaeodactylum tricornutum for the Detection of Amyloid Burden in Transgenic Mouse Models of Alzheimer's Disease

Abstract

The visualization of misfolded A beta peptides by using fluorescence chemical dyes is very important in Alzheimer's disease (AD) diagnosis. Here, we describe the fluorescent substance, fucoxanthin, which detects A beta aggregates in the brain of AD transgenic mouse models. We found that fucoxanthin from the microalgae Phaeodactylum tricornutum has fluorescent excitation and emission wavelengths without any interference for A beta interaction. Thus, we applied it to monitor A beta aggregation in AD transgenic mouse models. A beta plaques were visualized using fucoxanthin in the brain tissue of APP/PS1 and 5xFAD mice by histological staining with different staining methods. By comparing fucoxanthin-positive and thioflavin S-positive stained regions in the brains, we found that they are colocalized and that fucoxanthin can detect A beta aggregates. Our finding suggests that fucoxanthin from P. tricornutum can be a new A beta fluorescent imaging reagent in AD diagnosis.