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Updated: Mar 25, 2026
Studying Pre-formed Fibril Induced α-Synuclein Accumulation in Primary Embryonic Mouse Midbrain Dopamine Neurons
Published on: August 16, 2020
Alpha-synuclein co-pathology in a real-world early Alzheimer's disease cohort
Tamara Shiner1,2,3,4, Talya Nathan1, Mori Hai Levy1
1Cognitive Neurology Unit, Neurological Institute, Tel Aviv Medical Center, Tel Aviv, Israel.
Background:
Most Alzheimer's disease (AD) cases show mixed pathology, with α-synuclein (αSyn) aggregates present in a substantial proportion. The cerebrospinal fluid (CSF) α-synuclein seed amplification assay (αS-SAA) enables in vivo detection of pathogenic αSyn aggregates, but its clinical significance remains unclear.
Methods:
We prospectively evaluated 108 individuals with mild cognitive impairment or mild dementia due to suspected AD undergoing lumbar puncture for anti-amyloid therapy (ATT) eligibility. CSF AD biomarkers and αS-SAA were analyzed alongside cognitive, olfactory, and rapid eye movement sleep behavior disorder (RBD) assessments.
Results:
Of 65 participants with biomarker-confirmed AD, 21 (32.3%) were αS-SAA positive. Positivity was linked to older age at testing and self-reported olfactory impairment (P = 0.004), but not other demographic or cognitive features. Within the αS-SAA-positive group, RBD presence correlated with faster seeding kinetics.
Conclusions:
αS-SAA positivity is common in early AD and associated with olfactory dysfunction. Longitudinal follow-up is required to test if assay status predicts response to ATTs.
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