Radiation and Environmental Biophysics

, Volume 56, Issue 2, pp 193–200 | Cite as

Assessing the combined effect of extremely low-frequency magnetic field exposure and oxidative stress on LINE-1 promoter methylation in human neural cells

  • Gianfranco Giorgi
  • Chiara Pirazzini
  • Maria Giulia Bacalini
  • Cristina Giuliani
  • Paolo Garagnani
  • Miriam Capri
  • Ferdinando Bersani
  • Brunella Del Re
Original Article


Extremely low frequency magnetic fields (ELF-MF) have been classified as “possibly carcinogenic”, but their genotoxic effects are still unclear. Recent findings indicate that epigenetic mechanisms contribute to the genome dysfunction and it is well known that they are affected by environmental factors. To our knowledge, to date the question of whether exposure to ELF-MF can influence epigenetic modifications has been poorly addressed. In this paper, we investigated whether exposure to ELF-MF alone and in combination with oxidative stress (OS) can affect DNA methylation, which is one of the most often studied epigenetic modification. To this end, we analyzed the DNA methylation levels of the 5′untranslated region (5′UTR) of long interspersed nuclear element-1s (LINE-1 or L1), which are commonly used to evaluate the global genome methylation level. Human neural cells (BE(2)C) were exposed for 24 and 48 h to extremely low frequency pulsed magnetic field (PMF; 50 Hz, 1 mT) in combination with OS. The methylation levels of CpGs located in L1 5′UTR region were measured by MassARRAY EpiTYPER. The results indicate that exposures to the single agents PMF and OS induced weak decreases and increases of DNA methylation levels at different CpGs. However, the combined exposure to PMF and OS lead to significant decrease of DNA methylation levels at different CpG sites. Most of the changes were transient, suggesting that cells can restore homeostatic DNA methylation patterns. The results are discussed and future research directions outlined.


DNA methylation Epigenetics LINE-1 Retrotransposition Extremely low frequency magnetic field Oxidative stress 



This work was supported by RFO (Ricerca Fondamentale Orientata, Oriented Fundamental Research) grants from the University of Bologna to BDR and to MC. Funds were also obtained by Fondazione Pallotti to PG and MC.

Compliance with ethical standards

Conflict of interest

The authors report no conflicts of interests. The authors alone are responsible for the content and writing of the paper.


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Copyright information

© Springer-Verlag Berlin Heidelberg 2017

Authors and Affiliations

  • Gianfranco Giorgi
    • 1
  • Chiara Pirazzini
    • 2
  • Maria Giulia Bacalini
    • 2
  • Cristina Giuliani
    • 3
  • Paolo Garagnani
    • 2
    • 4
  • Miriam Capri
    • 2
    • 4
  • Ferdinando Bersani
    • 5
  • Brunella Del Re
    • 1
  1. 1.Department of Pharmacy and Biotechnology (FaBiT)University of BolognaBolognaItaly
  2. 2.Department of Experimental, Diagnostic and Specialty Medicine (DIMES)University of BolognaBolognaItaly
  3. 3.Department of Biological, Geological and Environmental Sciences (BiGeA), Centre for Genome BiologyUniversity of BolognaBolognaItaly
  4. 4.CIG-Interdepartmental Centre “L. Galvani” for Bioinformatics, Biophysics and BiocomplexityBolognaItaly
  5. 5.DIFA Department of Physics and AstronomyUniversity of BolognaBolognaItaly

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