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Plasma A? analysis using magnetically-labeled immunoassays and PET 18F-florbetapir binding in non-demented patients with major depressive disorder.

ABSTRACT: An increased level of brain amyloid deposition and a decreased level of cerebral spinal fluid (CSF) A?42 are currently considered reliable biomarkers of Alzheimer's disease (AD); however, the usefulness of plasma A? levels are not well-established. This study investigated the relationships between plasma A? levels and cerebral amyloidosis in 36 non-demented patients with major depressive disorder (MDD). All participants underwent 18F-florbetapir PET imaging and provided a blood sample at the same time for immunomagnetic reduction assay to measure the plasma levels of A?40 and A?42. We found inverse associations of the plasma A?42 level and the A?42/A?40 ratio, and a positive association of the plasma A?40 level, with cerebral amyloid deposition in the precuneus, parietal and posterior cingulate cortex. Subgroup analyses in subjects with higher 18F-florbetapir uptake values or MDD with amnestic mild cognitive impairment revealed more pervasive relationships of plasma A? measures with 18F-florbetapir binding across the brain regions examined. The study suggested that regional brain amyloid deposition in terms of 18F-florbetapir PET uptake had weak-to-moderate associations with plasma A?42 and A?40 levels, and the A?42/A?40 ratio. Validation in a larger population of subjects of known cerebral amyloidosis status is needed. Careful interpretation of plasma data is warranted.

SUBMITTER: Wu KY

PROVIDER: S-EPMC5807319 | biostudies-literature | 2018 Feb

REPOSITORIES: biostudies-literature

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Plasma Aβ analysis using magnetically-labeled immunoassays and PET <sup>18</sup>F-florbetapir binding in non-demented patients with major depressive disorder.

Wu Kuan-Yi KY Hsiao Ing-Tsung IT Chen Chia-Hsiang CH Liu Chia-Yih CY Hsu Jung-Lung JL Huang Sheng-Yao SY Yen Tzu-Chen TC Lin Kun-Ju KJ

Scientific reports 20180209 1

An increased level of brain amyloid deposition and a decreased level of cerebral spinal fluid (CSF) Aβ42 are currently considered reliable biomarkers of Alzheimer's disease (AD); however, the usefulness of plasma Aβ levels are not well-established. This study investigated the relationships between plasma Aβ levels and cerebral amyloidosis in 36 non-demented patients with major depressive disorder (MDD). All participants underwent <sup>18</sup>F-florbetapir PET imaging and provided a blood sample ...[more]

PMID: 29426824

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Dataset Information

Plasma A? analysis using magnetically-labeled immunoassays and PET 18F-florbetapir binding in non-demented patients with major depressive disorder.

Publications

Plasma Aβ analysis using magnetically-labeled immunoassays and PET <sup>18</sup>F-florbetapir binding in non-demented patients with major depressive disorder.

Similar Datasets

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