Evidence map›Paper›PMID 41761294›Full record

Observational studyAlzheimer's research & therapy2026

Association of circulating proteasome activity with Alzheimer's pathology and cognitive functions in APOE ε4 carriers.

Bon Gook Koo, Ha-Eun Seo, Yejin Yun, Daegyeom Kim, Jae Myeong Kang, Jaelim Cho, Sang-Yoon Lee, Yu Joo Lee, Kee Hyung Park, Min Jae Lee and 1 more

Abstract readObservational Study
In one paragraph

Observational study in Alzheimer's research & therapy, 2026. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 2 papers.

0numbers the graph read from it
0cells of the map it votes in
2citing papers in PubMed
–field-weighted citation impact
1 · What the graph read from it

What it found

Each row is one number read from the abstract, on the scale the paper reported it, with its interval. Left of the dashed line favours the treatment, right favours the comparator. Under each row is the sentence it came from. New to these charts? A ten-minute tutorial.

The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.

2 · The registry

The trial behind it

Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.

Neither the registry nor the abstract names a trial number. If this is a trial report, that itself is worth knowing.

3 · Its place in the literature

Who cites it

2 citing papers in PubMed.

  1. APOE4 disrupts the central dogma by arresting neuronal proteome dynamics.bioRxiv : the preprint server for biology · 2026
    Article
  2. Review
4 · The record

Corrections and comments

PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.

5 · Who and what money

Authors and funding

11 authors.

Bon Gook Koo *Department of Neurology, Gil Medical Center, Gachon University College of Medicine, 21, Namdong-daero, 774 beon-gil, Namdong-gu, Incheon, 21565, Republic of Korea.
Ha-Eun Seo *Neuroscience Research Institute, Gachon University, Incheon, Republic of Korea.
Yejin YunDepartment of Otorhinolaryngology, Seoul National University Hospital, Seoul, Republic of Korea.
Daegyeom KimNeuroscience Research Institute, Gachon University, Incheon, Republic of Korea.
Jae Myeong KangDepartment of Psychiatry, Gil Medical Center, Gachon University College of Medicine, Incheon, Republic of Korea.
Jaelim ChoDepartment of Preventive Medicine, Yonsei University College of Medicine, Seoul, Republic of Korea.
Sang-Yoon LeeDepartment of Neuroscience, College of Medicine, Gachon University, Incheon, Republic of Korea.
Yu Joo LeeDepartment of Genome Medicine and Science, Gachon University College of Medicine, Incheon, Republic of Korea.
Kee Hyung ParkDepartment of Neurology, Gil Medical Center, Gachon University College of Medicine, 21, Namdong-daero, 774 beon-gil, Namdong-gu, Incheon, 21565, Republic of Korea.
Min Jae LeeDepartment of Biochemistry and Molecular Biology, Seoul National University College of Medicine, 103 Daehak-ro, Jongno-gu, Seoul, 03080, Republic of Korea. minjlee@snu.ac.kr.
Young NohDepartment of Neurology, Gil Medical Center, Gachon University College of Medicine, 21, Namdong-daero, 774 beon-gil, Namdong-gu, Incheon, 21565, Republic of Korea. nymed77@gmail.com.

Funding

Gil Medical Center, Gachon University FRD2025-01Ministry of Education RS-2021-NR060117the Ministry of Health & Welfare and Ministry of Science and ICT, Republic of Korea RS-2024-00332875The Ministry of Health & Welfare and Ministry of Science and ICT, Republic of Korea RS-2024-00334574The Ministry of Health & Welfare, Republic of Korea HI14C1135the National Research Foundation (NRF) of Korea RS-2021-NR059245
6 · The paper itself

Abstract

backgroundThe proteasome is a major intracellular protease complex, but the significance of circulating proteasome activity in Alzheimer’s disease (AD) is not well established. Because APOE ε4 is the strongest genetic risk factor for AD, we examined whether plasma proteasome activity is associated with AD-related pathology, neurodegeneration, and cognitive decline, focusing on APOE ε4 carriers.

methodsIn this observational study, participants were classified as cognitively normal (CN), mild cognitive impairment (MCI), and dementia. All underwent 3.0-T MRI, [18F]flutemetamol PET for amyloid, [18F]MK-6240 PET for tau, APOE genotyping, and neuropsychological testing. Circulating proteasome activity was measured using fluorogenic substrates. Associations between proteasome activity and imaging or clinical features were assessed after stratifying by APOE ε4 status. Mediation analyses evaluated whether amyloid or tau burden indirectly linked proteasome activity with hippocampal volume or cognition.

resultsA total of 148 individuals were included (58 CN, 39 MCI, 38 AD dementia, and 13 other dementia). Significant associations appeared only in APOE ε4 carriers (n = 55). Higher proteasome activity was associated with lower amyloid burden (β = − 0.336, p = 0.009), lower global tau burden (β = − 0.268, p = 0.047), and reduced tau in Braak I/II (β = − 0.298, p = 0.033) and Braak III/IV regions (β = − 0.296, p = 0.033). Proteasome activity was positively associated with hippocampal volume (β = 0.374, p = 0.001) and with cognitive performance, including MMSE (β = 0.294, p = 0.026), CDR-SOB (β = − 0.365, p = 0.005). No significant associations were found in noncarriers. Mediation analyses showed that amyloid burden explained ~ 29% and Braak I/II tau ~ 23% of the proteasome–hippocampal volume relationship, while tau in Braak I/II and III/IV regions mediated 24–41% of the associations between proteasome activity and global cognition.

conclusionsDownregulated proteasome activity is strongly associated with amyloid burden, early tau accumulation, hippocampal atrophy, and cognitive impairment only in APOE ε4 carriers. These findings suggest that plasma proteasome activity may serve as a noninvasive marker of AD-related vulnerability in genetically at-risk individuals. Further studies are needed to clarify whether proteasome activity contributes to or results from amyloid and tau aggregation.

trial registrationKCT0005428. Registered September 24, 2020. Study subjects included in this analysis were those recruited from November 2018 onwards (retrospectively registered).

Indexed as

Alzheimer DiseaseApolipoprotein E4CognitionCognitive DysfunctionProteasome Endopeptidase ComplexAgedAged, 80 and overAniline CompoundsFemaleHeterozygoteHippocampusHumansMagnetic Resonance ImagingMaleNeuropsychological TestsPositron-Emission TomographyAniline CompoundsApolipoprotein E4Proteasome Endopeptidase Complextau ProteinsAlzheimer’s diseaseAmyloidAPOE ε4BiomarkerCognitionPETPlasmaProteasomeTau

Identifiers

PMID41761294
PMCPMC13059596

What OpenQuestion holds

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Registered trials

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Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.