Dataset Information

Alzheimer disease pathology and the cerebrospinal fluid proteome.

ABSTRACT:

Background

Altered proteome profiles have been reported in both postmortem brain tissues and body fluids of subjects with Alzheimer disease (AD), but their broad relationships with AD pathology, amyloid pathology, and tau-related neurodegeneration have not yet been fully explored. Using a robust automated MS-based proteomic biomarker discovery workflow, we measured cerebrospinal fluid (CSF) proteomes to explore their association with well-established markers of core AD pathology.

Methods

Cross-sectional analysis was performed on CSF collected from 120 older community-dwelling adults with normal (n?=?48) or impaired cognition (n?=?72). LC-MS quantified hundreds of proteins in the CSF. CSF concentrations of ?-amyloid 1-42 (A?_1-42), tau, and tau phosphorylated at threonine 181 (P-tau181) were determined with immunoassays. First, we explored proteins relevant to biomarker-defined AD. Then, correlation analysis of CSF proteins with CSF markers of amyloid pathology, neuronal injury, and tau hyperphosphorylation (i.e., A?_1-42, tau, P-tau181) was performed using Pearson's correlation coefficient and Bonferroni correction for multiple comparisons.

Results

We quantified 790 proteins in CSF samples with MS. Four CSF proteins showed an association with CSF A?_1-42 levels (p value ??0.05 with correlation coefficient (R)???0.38). We identified 50 additional CSF proteins associated with CSF tau and 46 proteins associated with CSF P-tau181 (p value ??0.05 with R???0.37). The majority of those proteins that showed such associations were brain-enriched proteins. Gene Ontology annotation revealed an enrichment for synaptic proteins and proteins originating from reelin-producing cells and the myelin sheath.

Conclusions

We used an MS-based proteomic workflow to profile the CSF proteome in relation to cerebral AD pathology. We report strong evidence of previously reported CSF proteins and several novel CSF proteins specifically associated with amyloid pathology or neuronal injury and tau hyperphosphorylation.

SUBMITTER: Dayon L

PROVIDER: S-EPMC6052524 | biostudies-literature | 2018 Jul

REPOSITORIES: biostudies-literature

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Publications

Alzheimer disease pathology and the cerebrospinal fluid proteome.

Dayon Loïc L Núñez Galindo Antonio A Wojcik Jérôme J Cominetti Ornella O Corthésy John J Oikonomidi Aikaterini A Henry Hugues H Kussmann Martin M Migliavacca Eugenia E Severin India I Bowman Gene L GL Popp Julius J

Alzheimer's research & therapy 20180718 1

<h4>Background</h4>Altered proteome profiles have been reported in both postmortem brain tissues and body fluids of subjects with Alzheimer disease (AD), but their broad relationships with AD pathology, amyloid pathology, and tau-related neurodegeneration have not yet been fully explored. Using a robust automated MS-based proteomic biomarker discovery workflow, we measured cerebrospinal fluid (CSF) proteomes to explore their association with well-established markers of core AD pathology.<h4>Meth ...[more]

PMID: 30021611

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Dataset Information

Alzheimer disease pathology and the cerebrospinal fluid proteome.

Background

Methods

Results

Conclusions

Publications

Alzheimer disease pathology and the cerebrospinal fluid proteome.

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