Abstract
Purpose: The present study was conducted to re-evaluate the effect of low-level 1800 MHz RF signals on RAS/MAPK activation in live cells.
Material and methods: Using Bioluminescence Resonance Energy Transfer technique (BRET), we assessed the effect of Continuous wave (CW) and Global System for Mobile (GSM)-modulated 1800 MHz signals (up to 2 W/kg) on ERK and RAS kinases' activity in live HuH7 cells.
Results: We found that radiofrequency field (RF) exposure for 24 h altered neither basal level of RAS and ERK activation nor the potency of phorbol-12-myristate-13-acetate (PMA) to activate RAS and ERK kinases. However, we found that exposure to GSM-modulated 1800 MHz signals at 2 W/kg decreased the PMA maximal efficacy to activate both RAS and ERK kinases' activity. Exposure with CW 1800 MHz signal at 2 W/kg only decreased maximal efficacy of PMA to activate ERK but not RAS. No effects of RF exposure at 0.5 W/kg was observed on maximal efficacy of PMA to activate either RAS or ERK whatever the signal used.
Conclusions: Our results indicate that RF exposure decreases the efficiency of the cascade of events, which, from the binding of PMA to its receptor(s), leads to the activation of RAS and ERK kinases.
Acknowledgments
We thank Bernard Veyret for his wise advice and proofreading of the manuscript.
Author contributions
YP conceived and designed the study. PL and DAC designed the device and performed the electromagnetic dosimetry. EP, LP, HJR, FPDG, AH, RR, and YP collected and assembled the data. AG performed the statistical analysis of the results. YP, IL, DAC, and PL wrote the manuscript. All coauthors read and approved the final manuscript.
Disclosure statement
No potential conflict of interest was reported by the author(s).
Additional information
Funding
Notes on contributors
Emmanuelle Poque
Emmanuelle Poque is a Biologist Engineer at the Polytechnic Institute of Bordeaux (Bordeaux INP), working on bioelectromagnetics at the cellular and molecular levels.
Delia Arnaud-Cormos
Delia Arnaud-Cormos, PhD, is an Associate Professor in the Xlim Research Institute, University of Limoges, France. Since 2018, she is a junior member of the Institut Universitaire de France (IUF). Her research interests concern nanosecond pulses/microwave exposure systems set-up and dosimetric characterization for bioelectromagnetic studies.
Lorenza Patrignoni
Lorenza Patrignoni, MPharm, is a master's student working on bioelectromagnetics at the cellular and molecular levels.
Hermanus J. Ruigrok
Hermanus J. Ruigrok, PhD, is a post-doctoral researcher working on bioelectronics.
Florence Poulletier De Gannes
Florence Poulletier de Gannes, PhD, is a CNRS research engineer at the IMS laboratory. Her research deals mainly with the adverse and beneficial biological effects of non-invasive electromagnetic fields funded by several national and foreign programmes. She also works on EMF health risk assessment.
Annabelle Hurtier
Annabelle Hurtier is a Bordeaux INP Biologist Technician at the IMS laboratory. She is in charge of animal facility and is a specialist in animal welfare.
Rémy Renom
Rémy Renom, Master degree, is a Biologist Engineer working on bioelectromagnetics at the cellular and molecular levels.
André Garenne
André Garenne, PharmD, PhD, is an Associate Professor and Researcher at CNRS UMR 5293 (IMN). He is working at Bordeaux University (France). His main research domains are computational neuroscience, statistics, neural data analysis and machine learning.
Isabelle Lagroye
Isabelle Lagroye, PhD, is a Director of studies at the Ecole Pratique des Hautes Etudes (EPHE) working at Bordeaux University, France. Her research deals mainly with the biological and toxicological effects of non-invasive electromagnetic fields. She is currently member of the Bruxelles-Capitale expert committee on non-ionising radiations.
Philippe Lévêque
Philippe Lévêque, PhD, is a CNRS Senior Scientist and the group leader of the BioEM group working on nanopulse applications in the XLIM Research Institute, University of Limoges. He is involved in the development of dosimetry and exposure setups for health-risk assessment in cooperation with biological and medical research groups.
Yann Percherancier
Yann Percherancier, PhD, is a CNRS Senior Scientist and is working at Bordeaux University (France). His main research focus on deciphering the effects of low-level electromagnetic fields on living matter at the cellular and molecular level.