Dataset Information

High Level of Real Urban Air Pollution Promotes Cardiac Arrhythmia in Healthy Mice.

ABSTRACT:

Background and objectives

Ambient particulate matter (PM) in real urban air pollution (RUA) is an environmental health risk factor associated with increased cardiac events. This study investigated the threshold level to induce arrhythmia, as well as arrhythmogenic mechanism of RUA that mainly consisted of PM <2.5 μm in aerodynamic diameter close to ultrafine particles.

Methods

RUA was artificially produced by a lately developed pyrolysis based RUA generator. C57BL/6 mice were divided into 4 groups: a control group (control, n=12) and three groups with exposure to RUA with the concentration of 200 μg/m³ (n=12), 400 μg/m³ (n=12), and 800 μg/m³ (n=12). Mice were exposed to RUA at each concentration for 8 hr/day and 5 day/week to mimic ordinary human activity during 3 weeks.

Results

The QRS and QTc intervals, as well as intracellular Ca²⁺ duration, apicobasal action potential duration (APD) gradient, fibrosis, and inflammation of left ventricle of mouse hearts were increased dose-dependently with the increase of RUA concentration, and significantly increased at RUA concentration of 400 μg/m³ compared to control (all p<0.001). In mice exposed to RUA concentration of 800 μg/m³, spontaneous ventricular arrhythmia was observed in 42%, with significant increase of inflammatory markers, phosphorylated Ca²⁺/calmodulin-dependent protein kinase II (CaMKII), and phospholamban (PLB) compared to control.

Conclusions

RUA could induce electrophysiological changes such as APD and QT prolongation, fibrosis, and inflammation dose-dependently, with significant increase of ventricular arrhythmia at the concentration of 400 μg/m³. RUA concentration of 800 μg/m³ increased phosphorylation of CaMKII and PLB.

SUBMITTER: Park H

PROVIDER: S-EPMC7853890 | biostudies-literature | 2021 Feb

REPOSITORIES: biostudies-literature

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Publications

High Level of Real Urban Air Pollution Promotes Cardiac Arrhythmia in Healthy Mice.

Park Hyewon H Lim Sangchul S Lee Seunghoon S Mun Dasom D Kang JiYoung J Kim Hyoeun H Park Hyelim H Kim Changsoo C Park Sunho S Lim Yeong Min YM Joung Boyoung B

Korean circulation journal 20210201 2

<h4>Background and objectives</h4>Ambient particulate matter (PM) in real urban air pollution (RUA) is an environmental health risk factor associated with increased cardiac events. This study investigated the threshold level to induce arrhythmia, as well as arrhythmogenic mechanism of RUA that mainly consisted of PM <2.5 μm in aerodynamic diameter close to ultrafine particles.<h4>Methods</h4>RUA was artificially produced by a lately developed pyrolysis based RUA generator. C57BL/6 mice were divi ...[more]

PMID: 33525071

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Dataset Information

High Level of Real Urban Air Pollution Promotes Cardiac Arrhythmia in Healthy Mice.

Background and objectives

Methods

Results

Conclusions

Publications

High Level of Real Urban Air Pollution Promotes Cardiac Arrhythmia in Healthy Mice.

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