Blood β‐synuclein is related to amyloid PET positivity in memory clinic patients
Patrick Oeckl, Marina Blūma, Marco Bucci, Steffen Halbgebauer, Konstantinos Chiotis, Anna Matton, Nicholas J. Ashton, Guglielmo Di Molfetta, Lana Grötschel, Miia Kivipelto, Kaj Blennow, Henrik Zetterberg, Irina Savitcheva, Agneta Nordberg, Markus Otto
Abstract
INTRODUCTION: β-synuclein is an emerging blood biomarker to study synaptic degeneration in Alzheimer´s disease (AD), but its relation to amyloid-β (Αβ) pathology is unclear. METHODS: flutemetamol positron emission tomography (PET) in patients with AD dementia (n = 51), mild cognitive impairment (MCI-Aβ+ n = 18, MCI- Aβ- n = 30), non-AD dementias (n = 22), and non-demented controls (n = 5). RESULTS: Plasma β-synuclein levels were higher in Aβ+ (AD dementia, MCI-Aβ+) than in Aβ- subjects (non-AD dementias, MCI-Aβ-) with good discrimination of Aβ+ from Aβ- subjects and prediction of Aβ status in MCI individuals. A positive correlation between plasma β-synuclein and Aβ PET was observed in multiple cortical regions across all lobes. DISCUSSION: Plasma β-synuclein demonstrated discriminative properties for Aβ PET positive and negative subjects. Our data underline that β-synuclein is not a direct marker of Aβ pathology and suggest different longitudinal dynamics of synaptic degeneration versus amyloid deposition across the AD continuum. HIGHLIGHTS: Blood and CSF β-synuclein levels are higher in Aβ+ than in Aβ- subjects. Blood β-synuclein level correlates with amyloid PET positivity in multiple regions. Blood β-synuclein predicts Aβ status in MCI individuals.