Environmental Health and Preventive Medicine
Online ISSN : 1347-4715
Print ISSN : 1342-078X
ISSN-L : 1342-078X
Reduction in mitochondrial DNA methylation leads to compensatory increase in mitochondrial DNA content: novel blood-borne biomarkers for monitoring occupational noise
Jia-Hao YangZhuo-Ran LiZhuo-Zhang TanWu-Zhong LiuQiang HouPin Sun Xue-Tao Zhang
Author information
JOURNAL OPEN ACCESS FULL-TEXT HTML
Supplementary material

2025 Volume 30 Pages 40

Details
Abstract

Background: Prolonged occupational noise exposure poses potential health risks, but its impact on mitochondrial DNA (mtDNA) damage and methylation patterns remains unclear.

Method: We recruited 306 factory workers, using average binaural high-frequency hearing thresholds from pure-tone audiometry to assess noise exposure. MtDNA damage was evaluated through mitochondrial DNA copy number (mtDNAcn) and lesion rate, and mtDNA methylation changes were identified via pyrophosphate sequencing.

Results: There was a reduction in MT-RNR1 methylation of 4.52% (95% CI: −7.43% to −1.62%) among workers with abnormal hearing, whereas changes in the D-loop region were not statistically significant (β = −2.06%, 95% CI: −4.44% to 0.31%). MtDNAcn showed a negative association with MT-RNR1 methylation (β = −0.95, 95% CI: −1.23 to −0.66), while no significant link was found with D-loop methylation (β = −0.05, 95% CI: −0.58 to 0.48). Mediation analysis indicated a significant increase in mtDNAcn by 10.75 units (95% CI: 3.00 to 21.26) in those with abnormal hearing, with MT-RNR1 methylation mediating 35.9% of this effect.

Conclusions: These findings suggest that occupational noise exposure may influence compensatory increases in mtDNA content through altered MT-RNR1 methylation.

Fullsize Image
Content from these authors

This article cannot obtain the latest cited-by information.

© The Author(s) 2025.

Open Access This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons licence, and indicate if changes were made. The images or other third party material in this article are included in the article's Creative Commons licence, unless indicated otherwise in a credit line to the material. If material is not included in the article's Creative Commons licence and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this licence, visit http://creativecommons.org/licenses/by/4.0/. The Creative Commons Public Domain Dedication waiver (http://creativecommons.org/publicdomain/zero/1.0/) applies to the data made available in this article, unless otherwise stated in a credit line to the data.
http://creativecommons.org/licenses/by/4.0/
Previous article Next article
feedback
Top