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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 38 out of 100. Disease mechanisms

Topic: Inflammation, microglia and astrocytes

The complement cascade not only is an innate immune response that enables removal of pathogens but also plays an important role in microglia-mediated synaptic refinement during brain development. Complement C3 is elevated in Alzheimer's disease (AD), colocalizing with neuritic plaques, and appears to contribute to clearance of Aβ by microglia in the brain. Previously, we reported that C3-deficient C57BL/6 mice were protected against age-related and region-specific loss of hippocampal synapses and cognitive decline during normal aging. Furthermore, blocking complement and downstream iC3b/CR3 signaling rescued synapses from Aβ-induced loss in young AD mice before amyloid plaques had accumulated. We assessed the effects of C3 deficiency in aged, plaque-rich APPswe/PS1dE9 transgenic mice (APP/PS1; C3 KO). We examined the effects of C3 deficiency on cognition, Aβ plaque deposition, and plaque-related neuropathology at later AD stages in these mice. We found that 16-month-old APP/PS1; C3 KO mice performed better on a learning and memory task than did APP/PS1 mice, despite having more cerebral Aβ plaques. Aged APP/PS1; C3 KO mice also had fewer microglia and astrocytes localized within the center of hippocampal Aβ plaques compared to APP/PS1 mice. Several proinflammatory cytokines in the brain were reduced in APP/PS1; C3 KO mice, consistent with an altered microglial phenotype. C3 deficiency also protected APP/PS1 mice against age-dependent loss of synapses and neurons. Our study suggests that complement C3 or downstream complement activation fragments may play an important role in Aβ plaque pathology, glial responses to plaques, and neuronal dysfunction in the brains of APP/PS1 mice.

Key findings

Study details

How this study scored 38/100
How this study's score is builtJournal tier 7 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 0 of 2. 22 of the 58 points it could be judged on, which is 38 of 100. Total 38 of 100.22 of the 58 points we could judge = 38 of 100

Published in a peer-reviewed journal. Scored zero for study design, sample size, effect reported 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 22 of the 58 points we could judge it on, which is 38 out of 100.

ComponentPointsWhy
Journal tier 7 / 10 Tier 3 — peer-reviewed journal (Science translational medicine)
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 2017 — 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 Laboratory or animal study (title names “app/ps1”) — scores zero
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 28566429)
Free to read 0 / 2 Behind a paywall — scores zero
Points 22 / 58 Scored on 11 of 20 parts. We have no data for the rest, so they are left out: 22 of the 58 points we could judge it on is 38 out of 100.
Total 38 / 100 —

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

Read the original

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Cite this study APA, Vancouver, BibTeX · download .bib or .ris

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

Shi, Q., Chowdhury, S., Ma, R., Le, K. X., Hong, S., Caldarone, B. J., et al. (2017). Complement C3 deficiency protects against neurodegeneration in aged plaque-rich APP/PS1 mice. Science translational medicine. https://doi.org/10.1126/scitranslmed.aaf6295

Vancouver

Shi Q, Chowdhury S, Ma R, Le KX, Hong S, Caldarone BJ, et al. Complement C3 deficiency protects against neurodegeneration in aged plaque-rich APP/PS1 mice. Science translational medicine. 2017. doi:10.1126/scitranslmed.aaf6295. PMID: 28566429.

BibTeX

@article{shi2017-28566429,
  author  = {Shi, Q. and Chowdhury, S. and Ma, R. and Le, K. X. and Hong, S. and Caldarone, B. J. and others},
  title   = {{Complement C3 deficiency protects against neurodegeneration in aged plaque-rich APP/PS1 mice}},
  journal = {Science translational medicine},
  year    = {2017},
  doi     = {10.1126/scitranslmed.aaf6295},
  pmid    = {28566429},
  url     = {https://doi.org/10.1126/scitranslmed.aaf6295}
}

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