Evidence map›Paper›PMID 34855899›Full record

ArticlePloS one2021

Association of air pollution and homocysteine with global DNA methylation: A population-based study from North India.

Suniti Yadav, Imnameren Longkumer, Priyanka Rani Garg, Shipra Joshi, Sunanda Rajkumari, Naorem Kiranmala Devi, Kallur Nava Saraswathy

Open access · goldAbstract read
In one paragraph

Article in PloS one, 2021. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 4 papers, 1 of them a synthesis that pooled it.

0numbers the graph read from it
0cells of the map it votes in
4citing papers in PubMed, 1 pooled it
0.5field-weighted citation impact, top 37% 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

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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

4 citing papers in PubMed, 1 synthesis or guideline pooled it, 7 citations in OpenAlex.

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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

7 authors at 2 institutions in 1 country.

Suniti YadavLaboratory of Biochemical and Molecular Anthropology, Department of Anthropology, University of Delhi, Delhi, India.
Imnameren LongkumerLaboratory of Biochemical and Molecular Anthropology, Department of Anthropology, University of Delhi, Delhi, India.
Priyanka Rani GargMAMTA Health Institute for Mother and Child, New Delhi, India.
Shipra JoshiManbhum Ananda Ashram Nityananda Trust-MANT, Kolkata, West Bengal, India.
Sunanda RajkumariLaboratory of Biochemical and Molecular Anthropology, Department of Anthropology, University of Delhi, Delhi, India.
Naorem Kiranmala DeviLaboratory of Biochemical and Molecular Anthropology, Department of Anthropology, University of Delhi, Delhi, India.
Kallur Nava SaraswathyLaboratory of Biochemical and Molecular Anthropology, Department of Anthropology, University of Delhi, Delhi, India.ORCID 0000-0002-0826-9675
University of Delhi · INMamta Health Institute for Mother and Child · IN

Funding

No grant is acknowledged in the PubMed record.

6 · The paper itself

Abstract

backgroundAnthropogenic air pollution has been implicated in aberrant changes of DNA methylation and homocysteine increase (>15μM/L). Folate (<3 ng/mL) and vitamin B12 (<220 pg/mL) deficiencies also reduce global DNA methylation via homocysteine increase. Although B-vitamin supplements can attenuate epigenetic effects of air pollution but such understanding in population-specific studies are lacking. Hence, the present study aims to understand the role of air pollution, homocysteine, and nutritional deficiencies on methylation.

methodsWe examined cross-sectionally, homocysteine, folate, vitamin B12 (chemiluminescence) and global DNA methylation (colorimetric ELISA Assay) among 274 and 270 individuals from low- and high- polluted areas, respectively, from a single Mendelian population. Global DNA methylation results were obtained on 254 and 258 samples from low- and high- polluted areas, respectively.

resultsSignificant decline in median global DNA methylation was seen as a result of air pollution [high-0.84 (0.37-1.97) vs. low-0.96 (0.45-2.75), p = 0.01]. High homocysteine in combination with air pollution significantly reduced global DNA methylation [high-0.71 (0.34-1.90) vs. low-0.93 (0.45-3.00), p = 0.003]. Folate deficient individuals in high polluted areas [high-0.70 (0.37-1.29) vs. low-1.21 (0.45-3.65)] showed significantly reduced global methylation levels (p = 0.007). In low polluted areas, despite folate deficiency, if normal vitamin B12 levels were maintained, global DNA methylation levels improved significantly [2.03 (0.60-5.24), p = 0.007]. Conversely, in high polluted areas despite vitamin B12 deficiency, if normal folate status was maintained, global DNA methylation status improved significantly [0.91 (0.36-1.63)] compared to vitamin B12 normal individuals [0.54 (0.26-1.13), p = 0.04].

conclusionsHigh homocysteine may aggravate the effects of air pollution on DNA methylation. Vitamin B12 in low-polluted and folate in high-polluted areas may be strong determinants for changes in DNA methylation levels. The effect of air pollution on methylation levels may be reduced through inclusion of dietary or supplemented B-vitamins. This may serve as public level approach in natural settings to prevent metabolic adversities at community level.

Indexed as

DNA MethylationAdultAgedAir PollutionCross-Sectional StudiesFemaleFolic Acid DeficiencyHomocysteineHumansHyperhomocysteinemiaIndiaMaleMiddle AgedVitamin B 12 DeficiencyHomocysteine

Identifiers

PMID34855899
PMCPMC8638980
OpenAlexW3216236634

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LicenceCC BY
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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.