Dataset Information

Cognitively normal APOE ε4 carriers have specific elevation of CSF SNAP-25.

ABSTRACT: Cerebrospinal fluid (CSF) synaptosomal-associated protein 25 (SNAP-25) and neurogranin (Ng) are recently described biomarkers for pre- and postsynaptic integrity known to be elevated in symptomatic Alzheimer disease (AD). Their relationship with Apolipoprotein E (APOE) ε4 carrier status, the major genetic risk factor for AD, remains unclear. In this study, CSF SNAP-25 and Ng were compared in cognitively normal APOE ε4 carriers and noncarriers (n = 274, mean age 65 ± 9.0 years, 39% APOE ε4 carriers, 58% female). CSF SNAP-25, not CSF Ng, was specifically elevated in APOE ε4 carriers versus noncarriers (5.95 ± 1.72 pg/mL, 4.44 ± 1.40 pg/mL, p < 0.0001), even after adjusting for age, sex, years of education, and amyloid status (p < 0.0001). CSF total tau (t-tau), phosphorylated-tau-181 (ptau181), and neurofilament light chain (NfL) also did not vary by APOE ε4 status. Our findings suggest APOE ε4 carriers have amyloid-related and amyloid-independent presynaptic disruption as reflected by elevated CSF SNAP-25 levels. In contrast, postsynaptic disruption as reflected by elevations in CSF neurogranin is related to amyloid status.

SUBMITTER: Butt OH

PROVIDER: S-EPMC8793109 | biostudies-literature | 2021 Jun

REPOSITORIES: biostudies-literature

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Cognitively normal APOE ε4 carriers have specific elevation of CSF SNAP-25.

Butt Omar H OH Long Justin M JM Henson Rachel L RL Herries Elizabeth E Sutphen Courtney L CL Fagan Anne M AM Cruchaga Carlos C Ladenson Jack H JH Holtzman David M DM Morris John C JC Ances Beau M BM Schindler Suzanne E SE

Neurobiology of aging 20210211

Cerebrospinal fluid (CSF) synaptosomal-associated protein 25 (SNAP-25) and neurogranin (Ng) are recently described biomarkers for pre- and postsynaptic integrity known to be elevated in symptomatic Alzheimer disease (AD). Their relationship with Apolipoprotein E (APOE) ε4 carrier status, the major genetic risk factor for AD, remains unclear. In this study, CSF SNAP-25 and Ng were compared in cognitively normal APOE ε4 carriers and noncarriers (n = 274, mean age 65 ± 9.0 years, 39% APOE ε4 carrie ...[more]

PMID: 33765432

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Cognitively normal APOE ε4 carriers have specific elevation of CSF SNAP-25.

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Cognitively normal APOE ε4 carriers have specific elevation of CSF SNAP-25.

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