Evidence map›Paper›PMID 37899210›Full record

ArticleEnvironmental health and preventive medicine2023

Association between urinary zinc excretion and isoflavone-metabolizing enterotypes among Japanese females: a cross-sectional study.

Tomoko Fujitani, Zhaoqing Lyu, Mariko Harada Sassa, Kouji H Harada

Open access · goldAbstract read
In one paragraph

Article in Environmental health and preventive medicine, 2023. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Not yet cited in PubMed.

0numbers the graph read from it
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0citing papers in PubMed
0.2field-weighted citation impact, top 50% of its field
1 · What the graph read from it

What it found

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2 · The registry

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3 · Its place in the literature

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0 citing papers in PubMed, 1 citations in OpenAlex.

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4 · The record

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5 · Who and what money

Authors and funding

4 authors at 1 institution in 1 country.

Tomoko FujitaniDepartment of Health and Environmental Sciences, Kyoto University Graduate School of Medicine.
Zhaoqing LyuDepartment of Health and Environmental Sciences, Kyoto University Graduate School of Medicine.
Mariko Harada SassaDepartment of Health and Environmental Sciences, Kyoto University Graduate School of Medicine.
Kouji H HaradaDepartment of Health and Environmental Sciences, Kyoto University Graduate School of Medicine.ORCID http://orcid.org/0000-0001-7319-123X
Kyoto University · JP

Funding

No grant is acknowledged in the PubMed record.

6 · The paper itself

Abstract

backgroundZinc absorption and competition among gut bacteria have been reported in animal studies. Thus, gut bacteria may modify zinc availability in humans. Metabolism of intestinal bacteria is known to be necessary for the activation of several phytoconstituents in the body. For example, equol, a typical substance of soybean isoflavone, is produced by intestinal bacteria metabolizing daidzein and the enterotype is one of distinct ones among Japanese population. The difference in the intestinal microflora can modify the bioavailability of zinc. In this study, we examined urinary zinc concentrations in adult female equol producers (EQPs).

methodsUrine samples from women participating in health examinations in Miyagi, Okinawa, Kyoto, Kochi, and Hokkaido prefectures were used; from total 17,484 samples, approximately 25 samples were randomly selected for each age group from 30 to 60 years per region (subsample: n = 520), and 520 samples with available urinary zinc concentration (determined by flame atomic absorption analysis) and enterobacterial type were analyzed. EQP was defined as log(equol/daidzein) ≥ -1.42, and urinary concentrations were corrected for creatinine concentration. Urinary zinc concentrations were compared by Student's t-test and multiple regression analyses.

resultsThe geometric mean urinary zinc concentration (µg/g-Cr) was lower in EQP than in non-EQP (p = 0.0136 by t-test after logarithm transformation). On the other hand, there was no correlation between urinary zinc concentration with daidzein (r = -0.0495, P = 0.436) and equol concentrations (r = -0.0721, P = 0.256). There was a significant negative association between urinary zinc concentration and EQP (β = -0.392, P = 0.0311) after adjusting with other potential confounding variables, such as daidzein intake.

conclusionsThe results suggest that gut bacteria that produce equol are involved in the metabolism of zinc. Based on previous studies, the bacteria that affect the metabolism of both substances are thought to be Enterococcus. Future studies are expected to identify specific intestinal bacteria for zinc availability and understand individual differences in the effects of micronutrients.

Indexed as

EquolGastrointestinal MicrobiomeIsoflavonesZincAdultAnimalsCross-Sectional StudiesEast Asian PeopleFemaleHumansMiddle AgedRandom AllocationEquolIsoflavonesZincEnterotypeIsoflavoneJapaneseMetabolismZinc

Identifiers

PMID37899210
PMCPMC10613555
OpenAlexW4388034586

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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.