Dataset Information

Air pollution exposure and telomere length in highly exposed subjects in Beijing, China: a repeated-measure study.

ABSTRACT:

Background

Ambient particulate matter (PM) exposure has been associated with short- and long-term effects on cardiovascular disease (CVD). Telomere length (TL) is a biomarker of CVD risk that is modified by inflammation and oxidative stress, two key pathways for PM effects. Whether PM exposure modifies TL is largely unexplored.

Objectives

To investigate effects of PM on blood TL in a highly-exposed population.

Methods

We measured blood TL in 120 blood samples from truck drivers and 120 blood samples from office workers in Beijing, China. We measured personal PM(2.5) and Elemental Carbon (EC, a tracer of traffic particles) using light-weight monitors. Ambient PM(10) was obtained from local monitoring stations. We used covariate-adjusted regression models to estimate percent changes in TL per an interquartile-range increase in exposure.

Results

Covariate-adjusted TL was higher in drivers (mean=0.87, 95%CI: 0.74; 1.03) than in office workers (mean=0.79, 95%CI: 0.67; 0.93; p=0.001). In all participants combined, TL increased in association with personal PM(2.5) (+5.2%, 95%CI: 1.5; 9.1; p=0.007), personal EC (+4.9%, 95%CI: 1.2; 8.8; p=0.01), and ambient PM(10) (+7.7%, 95%CI: 3.7; 11.9; p<0.001) on examination days. In contrast, average ambient PM(10) over the 14 days before the examinations was significantly associated with shorter TL (-9.9%, 95%CI: -17.6; -1.5; p=0.02).

Conclusions

Short-term exposure to ambient PM is associated with increased blood TL, consistent with TL roles during acute inflammatory responses. Longer exposures may shorten TL as expected after prolonged pro-oxidant exposures. The observed TL alterations may participate in the biological pathways of short- and long-term PM effects.

SUBMITTER: Hou L

PROVIDER: S-EPMC3821920 | biostudies-literature | 2012 Nov

REPOSITORIES: biostudies-literature

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Publications

Air pollution exposure and telomere length in highly exposed subjects in Beijing, China: a repeated-measure study.

Hou Lifang L Wang Sheng S Dou Chang C Zhang Xiao X Yu Yue Y Zheng Yinan Y Avula Umakanth U Hoxha Mirjam M Díaz Anaité A McCracken John J Barretta Francesco F Marinelli Barbara B Bertazzi Pier Alberto PA Schwartz Joel J Baccarelli Andrea A AA

Environment international 20120805

<h4>Background</h4>Ambient particulate matter (PM) exposure has been associated with short- and long-term effects on cardiovascular disease (CVD). Telomere length (TL) is a biomarker of CVD risk that is modified by inflammation and oxidative stress, two key pathways for PM effects. Whether PM exposure modifies TL is largely unexplored.<h4>Objectives</h4>To investigate effects of PM on blood TL in a highly-exposed population.<h4>Methods</h4>We measured blood TL in 120 blood samples from truck dri ...[more]

PMID: 22871507

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Project description:BackgroundTelomere length is a molecular marker of biological aging.ObjectiveHere we investigated whether early-life exposure to residential air pollution was associated with leukocyte telomere length (LTL) at 8 y of age.MethodsIn a multicenter European birth cohort study, HELIX (Human Early Life Exposome) ([Formula: see text]), we estimated prenatal and 1-y childhood exposure to nitrogen dioxide ([Formula: see text]), particulate matter with aerodynamic diameter [Formula: see text] ([Formula: see text]), and proximity to major roads. Average relative LTL was measured using quantitative real-time polymerase chain reaction (qPCR). Effect estimates of the association between LTL and prenatal, 1-y childhood air pollution, and proximity to major roads were calculated using multiple linear mixed models with a random cohort effect and adjusted for relevant covariates.ResultsLTL was inversely associated with prenatal and 1-y childhood [Formula: see text] and [Formula: see text] exposures levels. Each standard deviation (SD) increase in prenatal [Formula: see text] was associated with a [Formula: see text] (95% CI: [Formula: see text], [Formula: see text]) change in LTL. Prenatal [Formula: see text] was nonsignificantly associated with LTL ([Formula: see text] per SD increase; 95% CI: [Formula: see text], 0.6). For each SD increment in 1-y childhood [Formula: see text] and [Formula: see text] exposure, LTL shortened by [Formula: see text] (95% CI: [Formula: see text], [Formula: see text]) and [Formula: see text] (95% CI: [Formula: see text], 0.1), respectively. Each doubling in residential distance to nearest major road during childhood was associated with a 1.6% (95% CI: 0.02, 3.1) lengthening in LTL.ConclusionLower exposures to air pollution during pregnancy and childhood were associated with longer telomeres in European children at 8 y of age. These results suggest that reductions in traffic-related air pollution may promote molecular longevity, as exemplified by telomere length, from early life onward. https://doi.org/10.1289/EHP4148.

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Dataset Information

Air pollution exposure and telomere length in highly exposed subjects in Beijing, China: a repeated-measure study.

Background

Objectives

Methods

Results

Conclusions

Publications

Air pollution exposure and telomere length in highly exposed subjects in Beijing, China: a repeated-measure study.

Similar Datasets

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