Evidence map›Paper›PMID 31518386›Full record

ArticleThe American journal of clinical nutrition2019

Exploratory analysis of covariation of microbiota-derived vitamin K and cognition in older adults.

Angela McCann, Ian B Jeffery, Bouchra Ouliass, Guylaine Ferland, Xueyen Fu, Sarah L Booth, Tam T T Tran, Paul W O'Toole, Eibhlís M O'Connor

Open access · hybridAbstract read
PubMed Full text at PMC Publisher
In one paragraph

Article in The American journal of clinical nutrition, 2019. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 16 papers.

0numbers the graph read from it
0cells of the map it votes in
16citing papers in PubMed
3.4field-weighted citation impact, top 8% of its field
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

16 citing papers in PubMed, 40 citations in OpenAlex.

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  13. Article
  14. Role of Vitamin K in Intestinal Health.Frontiers in immunology · 2021
    Review
  15. Article
  16. Microbiome Influence in the Pathogenesis of Prion and Alzheimer's Diseases.International journal of molecular sciences · 2019
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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

9 authors at 4 institutions in 3 countries.

Angela McCannSchool of Microbiology, University College Cork, Cork, Ireland.
Ian B JefferySchool of Microbiology, University College Cork, Cork, Ireland.
Bouchra OuliassDépartement de Nutrition, Université de Montréal, Montreal, Canada.
Guylaine FerlandDépartement de Nutrition, Université de Montréal, Montreal, Canada.
Xueyen FuJean Mayer US Department of Agriculture Human Nutrition Research Center on Aging at Tufts University, Boston, MA, USA.
Sarah L BoothJean Mayer US Department of Agriculture Human Nutrition Research Center on Aging at Tufts University, Boston, MA, USA.
Tam T T TranSchool of Microbiology, University College Cork, Cork, Ireland.
Paul W O'TooleSchool of Microbiology, University College Cork, Cork, Ireland.
Eibhlís M O'ConnorAPC Microbiome Ireland, University College Cork, Cork, Ireland.
University College Cork · IETufts University · USUniversité de Montréal · CAUniversity of Limerick · IE

Funding

No grant is acknowledged in the PubMed record.

6 · The paper itself

Abstract

backgroundVitamin K has multiple important physiological roles, including blood coagulation and beneficial effects on myelin integrity in the brain. Some intestinal microbes possess the genes to produce vitamin K in the form of menaquinone (MK). MK appears in higher concentration in tissues, such as the brain, particularly MK4, than the dietary form of phylloquinone (PK). Lower PK concentrations have been reported in patients with Alzheimer disease while higher serum PK concentrations have been positively associated with verbal episodic memory. Despite knowledge of the importance of vitamin K for various health parameters, few studies have measured MK concentration and biosynthesis by gut commensals.

objectiveThe aim of the current study was to investigate the relation between genes involved in gut-microbiota derived MK, concentrations of MK isoforms, and cognitive function.

methodsShotgun metagenomic sequencing of the gut microbiome of 74 elderly individuals with different cognitive ability levels was performed. From this, gene counts for microbial MK biosynthesis were determined. Associations between clusters of individuals, grouped based on a similar presence and prevalence of MK biosynthesis genes, and cognitive ability were investigated. Fecal MK concentrations were quantified by HPLC to investigate correlations with subject clusters.

resultsSeparation of subject groups defined by banded quantification of the genetic potential of their microbiome to biosynthesize MK was associated with significant differences in cognitive ability [assessed using the Mini-Mental State Examination (MMSE)]. Three MK isoforms were found to be positively associated with MMSE, along with the identification of key components of the MK pathway that drive this association. Although the causality and direction of these associations remain unknown, these findings justify further studies.

conclusionsThis study provides evidence that although total concentrations of MK did not covary with cognition, certain MK isoforms synthesized by the gut microbiome, particularly the longer chains, are positively associated with cognition.

Indexed as

Gastrointestinal MicrobiomeAgedAged, 80 and overAgingBacteriaCognitionCohort StudiesFemaleHumansMaleMiddle AgedVitamin KVitamin K 1Vitamin KVitamin K 1cognitionelderlymicrobial menaquinone biosynthesisshotgun metagenomic sequencingvitamin K

Identifiers

PMID31518386
PMCPMC6885478
OpenAlexW2972534972

What OpenQuestion holds

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LicenceCC BY
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Registered trials

None linked

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.