Apoptosis is induced by radiofrequency fields through the caspase-independent mitochondrial pathway in cortical neurons

Radiat Res. 2008 Jan;169(1):38-45. doi: 10.1667/RR1077.1.


Joubert, V., Bourthoumieu, S., Leveque, P. and Yardin, C. Apoptosis is Induced by Radiofrequency Fields through the Caspase-Independent Mitochondrial Pathway in Cortical Neurons. Radiat. Res. 169, 38-45 (2008). In the present study, we investigated whether continuous-wave (CW) radiofrequency (RF) fields induce neuron apoptosis in vitro. Rat primary neuronal cultures were exposed to a CW 900 MHz RF field with a specific absorption rate (SAR) of 2 W/kg for 24 h. During exposure, an increase of 2 degrees C was measured in the medium; control experiments with neurons exposed to 39 degrees C were then performed. Apoptosis was assessed by condensation of nuclei with 4',6-diamino-2-phenylindole (DAPI) staining observed with an epifluorescence microscope and fragmentation of DNA with TdT-mediated dUTP nick-end labeling (TUNEL) analyzed by flow cytometry. A statistically significant difference in the rate of apoptosis was found in the RF-field-exposed neurons compared to the sham-, 37 degrees C- and 39 degrees C-exposed neurons either 0 or 24 h after exposure using both methods. To assess whether the observed apoptosis was caspase-dependent or -independent, assays measuring caspase 3 activity and apoptosis-inducing factor (AIF) labeling were performed. No increase in the caspase 3 activity was found, whereas the percentage of AIF-positive nuclei in RF-field-exposed neurons was increased by three- to sevenfold compared to other conditions. Our results show that, under the experimental conditions used, exposure of primary rat neurons to CW RF fields may induce a caspase-independent pathway to apoptosis that involves AIF.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Apoptosis / radiation effects*
  • Apoptosis Inducing Factor / metabolism
  • Caspase 3 / metabolism
  • Cells, Cultured
  • Mitochondria / metabolism*
  • Mitochondria / radiation effects*
  • Neurons / cytology*
  • Neurons / metabolism
  • Neurons / radiation effects*
  • Radio Waves / adverse effects*
  • Rats
  • Rats, Wistar
  • Signal Transduction / radiation effects*
  • Temperature


  • Apoptosis Inducing Factor
  • Caspase 3