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This page is alzhub.org's plain-English summary of a published study, not the paper itself. It is generated from the record we hold for this study, sourced and linked below — check the original for the full text and methods.

✓ Peer-reviewed alzhub usefulness score 47 out of 100. Tau biomarkers

Topic: Genetics and APOE

Vascular contributions to dementia and Alzheimer's disease are increasingly recognized 1-6 . Recent studies have suggested that breakdown of the blood-brain barrier (BBB) is an early biomarker of human cognitive dysfunction 7 , including the early clinical stages of Alzheimer's disease 5,8-10 . The E4 variant of apolipoprotein E (APOE4), the main susceptibility gene for Alzheimer's disease 11-14 , leads to accelerated breakdown of the BBB and degeneration of brain capillary pericytes 15-19 , which maintain BBB integrity 20-22 . It is unclear, however, whether the cerebrovascular effects of APOE4 contribute to cognitive impairment. Here we show that individuals bearing APOE4 (with the ε3/ε4 or ε4/ε4 alleles) are distinguished from those without APOE4 (ε3/ε3) by breakdown of the BBB in the hippocampus and medial temporal lobe. This finding is apparent in cognitively unimpaired APOE4 carriers and more severe in those with cognitive impairment, but is not related to amyloid-β or tau pathology measured in cerebrospinal fluid or by positron emission tomography 23 . High baseline levels of the BBB pericyte injury biomarker soluble PDGFRβ 7,8 in the cerebrospinal fluid predicted future cognitive decline in APOE4 carriers but not in non-carriers, even after controlling for amyloid-β and tau status, and were correlated with increased activity of the BBB-degrading cyclophilin A-matrix metalloproteinase-9 pathway 19 in cerebrospinal fluid. Our findings suggest that breakdown of the BBB contributes to APOE4-associated cognitive decline independently of Alzheimer's disease pathology, and might be a therapeutic target in APOE4 carriers.

Key findings

Study details

How this study scored 47/100
How this study's score is builtJournal tier 10 of 10; Journal's citation record left out, no data; Study design 0 of 12; Strength of evidence 1 of 5; Peer-review validation 10 of 10; How recent 2 of 5; Sample size 0 of 4; Effect reported 0 of 3; Studied in people 0 of 3; Randomised / blinded 0 of 2; Times cited left out, no data; Citations per year left out, no data; Impact for its field and year left out, no data; Cited by studies here left out, no data; Still being cited left out, no data; Senior author's track record left out, no data; Institution's track record left out, no data; Multi-centre collaboration left out, no data; Indexed in PubMed 2 of 2; Free to read 2 of 2. 27 of the 58 points it could be judged on, which is 47 of 100. Total 47 of 100.27 of the 58 points we could judge = 47 of 100

Published in a top-tier journal. Scored zero for study design, sample size, effect reported, studied in people and randomised / blinded because the record does not state it. We have no data on journal's citation record, times cited, citations per year, impact for its field and year, cited by studies here, still being cited, senior author's track record, institution's track record and multi-centre collaboration, so those were left out: it earned 27 of the 58 points we could judge it on, which is 47 out of 100.

ComponentPointsWhy
Journal tier 10 / 10 Tier 1 — top-tier general journal (Nature)
Journal's citation record — / 4 No journal record from OpenAlex — left out of this score
Study design 0 / 12 No study design recorded — scores zero, not guessed (not stated in the record — scored 0)
Strength of evidence 1 / 5 Rated “low” in our summary
Peer-review validation 10 / 10 Peer-reviewed. Published as an article in a named peer-reviewed journal.
How recent 2 / 5 2020 — within 10 year(s) of the newest study here
Sample size 0 / 4 Participant count not stated — scores zero (not stated in the record — scored 0)
Effect reported 0 / 3 No effect size reported — scores zero (not stated in the record — scored 0)
Studied in people 0 / 3 Not stated whether this was studied in people — scores zero (not stated in the record — scored 0)
Randomised / blinded 0 / 2 No randomisation or blinding stated — scores zero (not stated in the record — scored 0)
Times cited — / 7 No citation count (not found in OpenAlex) — left out of this score
Citations per year — / 5 No citation count or no year — left out of this score
Impact for its field and year — / 6 No field-weighted citation impact (OpenAlex has none yet) — left out of this score
Cited by studies here — / 6 Not yet checked against this library's citation graph — left out of this score
Still being cited — / 4 No yearly citation counts — left out of this score
Senior author's track record — / 4 Senior author's record not available — left out of this score
Institution's track record — / 3 No institution listed in OpenAlex — left out of this score
Multi-centre collaboration — / 3 Institutions not listed — left out of this score
Indexed in PubMed 2 / 2 Indexed in PubMed (PMID 32376954)
Free to read 2 / 2 Free to read
Points 27 / 58 Scored on 11 of 20 parts. We have no data for the rest, so they are left out: 27 of the 58 points we could judge it on is 47 out of 100.
Total 47 / 100 —

What each of these 20 components measures, and what this score is not →

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Built from the record alzhub holds for this paper, not looked up. Volume, issue and page numbers are not held in the record. The record's author list ends in “et al.”, so not every author is named. Check the citation against the original before you use it.

APA 7th

Montagne, A., Nation, D. A., Sagare, A. P., Barisano, G., Sweeney, M. D., Chakhoyan, A., et al. (2020). APOE4 leads to blood-brain barrier dysfunction predicting cognitive decline. Nature. https://doi.org/10.1038/s41586-020-2247-3

Vancouver

Montagne A, Nation DA, Sagare AP, Barisano G, Sweeney MD, Chakhoyan A, et al. APOE4 leads to blood-brain barrier dysfunction predicting cognitive decline. Nature. 2020. doi:10.1038/s41586-020-2247-3. PMID: 32376954.

BibTeX

@article{montagne2020-32376954,
  author  = {Montagne, A. and Nation, D. A. and Sagare, A. P. and Barisano, G. and Sweeney, M. D. and Chakhoyan, A. and Pachicano, M. and Joe, E. and others},
  title   = {{APOE4 leads to blood-brain barrier dysfunction predicting cognitive decline}},
  journal = {Nature},
  year    = {2020},
  doi     = {10.1038/s41586-020-2247-3},
  pmid    = {32376954},
  url     = {https://doi.org/10.1038/s41586-020-2247-3}
}

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