Association of Plasma Clusterin Concentration With Severity, Pathology, and Progression in Alzheimer Disease Plasma Clusterin and Alzheimer Disease

Thambisetty M, Simmons A, Velayudhan L, et al. — Thu, 01 Jul 2010 00:00:00 GMT

Context

Blood-based analytes may be indicators of pathological processes in Alzheimer disease (AD).

Objective

To identify plasma proteins associated with AD pathology using a combined proteomic and neuroimaging approach.

Design

Discovery-phase proteomics to identify plasma proteins associated with correlates of AD pathology. Confirmation and validation using immunodetection in a replication set and an animal model.

Setting

A multicenter European study (AddNeuroMed) and the Baltimore Longitudinal Study of Aging.

Participants

Patients with AD, subjects with mild cognitive impairment, and healthy controls with standardized clinical assessments and structural neuroimaging.

Main Outcome Measures

Association of plasma proteins with brain atrophy, disease severity, and rate of clinical progression. Extension studies in humans and transgenic mice tested the association between plasma proteins and brain amyloid.

Results

Clusterin/apolipoprotein J was associated with atrophy of the entorhinal cortex, baseline disease severity, and rapid clinical progression in AD. Increased plasma concentration of clusterin was predictive of greater fibrillar amyloid-β burden in the medial temporal lobe. Subjects with AD had increased clusterin messenger RNA in blood, but there was no effect of single-nucleotide polymorphisms in the gene encoding clusterin with gene or protein expression. APP/PS1 transgenic mice showed increased plasma clusterin, age-dependent increase in brain clusterin, as well as amyloid and clusterin colocalization in plaques.

Conclusions

These results demonstrate an important role of clusterin in the pathogenesis of AD and suggest that alterations in amyloid chaperone proteins may be a biologically relevant peripheral signature of AD.

JAMA Psychiatry: Pathology & Laboratory Medicine Topic Collection

Association of Plasma Clusterin Concentration With Severity, Pathology, and Progression in Alzheimer Disease Plasma Clusterin and Alzheimer Disease