Dataset Information

Blood-brain barrier integrity impacts the use of plasma amyloid-β as a proxy of brain amyloid-β pathology.

ABSTRACT:

Introduction

Amyloid-β (Aβ) and tau can be quantified in blood. However, biological factors can influence the levels of brain-derived proteins in the blood. The blood-brain barrier (BBB) regulates protein transport between cerebrospinal fluid (CSF) and blood. BBB altered permeability might affect the relationship between brain and blood biomarkers.

Methods

We assessed 224 participants in research (TRIAD, n = 96) and clinical (BIODEGMAR, n = 128) cohorts with plasma and CSF/positron emission tomography Aβ, p-tau, and albumin measures.

Results

Plasma Aβ_42/40 better identified CSF Aβ_42/40 and Aβ-PET positivity in individuals with high BBB permeability. An interaction between plasma Aβ_42/40 and BBB permeability on CSF Aβ_42/40 was observed. Voxel-wise models estimated that the association of positron emission tomography (PET), with plasma Aβ was most affected by BBB permeability in AD-related brain regions. BBB permeability did not significantly impact the relationship between brain and plasma p-tau levels.

Discussion

These findings suggest that BBB integrity may influence the performance of plasma Aβ, but not p-tau, biomarkers in research and clinical settings.

Highlights

BBB permeability affects the association between brain and plasma Aβ levels. BBB integrity does not affect the association between brain and plasma p-tau levels. Plasma Aβ was most affected by BBB permeability in AD-related brain regions. BBB permeability increases with age but not according to cognitive status.

SUBMITTER: Bellaver B

PROVIDER: S-EPMC10502181 | biostudies-literature | 2023 Sep

REPOSITORIES: biostudies-literature

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Publications

Blood-brain barrier integrity impacts the use of plasma amyloid-β as a proxy of brain amyloid-β pathology.

Bellaver Bruna B Puig-Pijoan Albert A Ferrari-Souza João Pedro JP Leffa Douglas T DT Lussier Firoza Z FZ Ferreira Pamela C L PCL Tissot Cécile C Povala Guilherme G Therriault Joseph J Benedet Andréa L AL Ashton Nicholas J NJ Servaes Stijn S Chamoun Mira M Stevenson Jenna J Rahmouni Nesrine N Vermeiren Marie M Macedo Arthur C AC Fernández-Lebrero Aida A García-Escobar Greta G Navalpotro-Gómez Irene I Lopez Oscar O Tudorascu Dana L DL Cohen Ann A Villemagne Victor L VL Klunk William E WE Gauthier Serge S Zimmer Eduardo R ER Karikari Thomas K TK Blennow Kaj K Zetterberg Henrik H Suárez-Calvet Marc M Rosa-Neto Pedro P Pascoal Tharick A TA

Alzheimer's & dementia : the journal of the Alzheimer's Association 20230315 9

<h4>Introduction</h4>Amyloid-β (Aβ) and tau can be quantified in blood. However, biological factors can influence the levels of brain-derived proteins in the blood. The blood-brain barrier (BBB) regulates protein transport between cerebrospinal fluid (CSF) and blood. BBB altered permeability might affect the relationship between brain and blood biomarkers.<h4>Methods</h4>We assessed 224 participants in research (TRIAD, n = 96) and clinical (BIODEGMAR, n = 128) cohorts with plasma and CSF/positro ...[more]

PMID: 36919582

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Dataset Information

Blood-brain barrier integrity impacts the use of plasma amyloid-β as a proxy of brain amyloid-β pathology.

Introduction

Methods

Results

Discussion

Highlights

Publications

Blood-brain barrier integrity impacts the use of plasma amyloid-β as a proxy of brain amyloid-β pathology.

Similar Datasets

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