Tauopathies and synucleinopathies: Do cerebrospinal fluid beta-amyloid peptides reflect disease-specific pathogenesis?

To evaluate variations in amyloid beta (A beta) peptide pattern in cerebrospinal fluid (CSF) in neurodegenerative disorders. A recently estabfished quantitative urea-based A beta-sodium-dodecylsulfate-polyacrylamide-gel-electrophoresis with western immunoblot (AP-SDS-PAGE/immunoblot) revealed a highly conserved A beta peptide (A beta 1-37, 1-38, 1-39, 1-40, 1-42) pattern in CSF. We asked whether the variation might be useful to further elucidate the overlap between or distinctions among neurodegenerative diseases in A beta-processing. We used the A beta-SDS-PAGE/immunoblot to investigate CSF for diseasespecific A beta peptide patterns. CSF samples from 96 patients with mainly clinically diagnosed Alzheimer's disease (n = 15), progressive supranuclear palsy (n = 20), corticobasal degeneration (n =: 12), Parkinson's disease (n = 11), multiple systems atrophy (n = 18), and dementia with Lewy-bodies (n = 20) were analysed as well a comparison group (n = 19). The A beta peptide patterns varied between tauopathies and synucleinopathies and between all diseases and the comparison group, possibly due to the influence of tau and a-synuctein on Ap-processing.