Format

Send to

Choose Destination
Cell Physiol Biochem. 2017;43(4):1533-1546. doi: 10.1159/000481977. Epub 2017 Oct 16.

Activation of Signaling Cascades by Weak Extremely Low Frequency Electromagnetic Fields.

Author information

1
Department of Biological Regulation, the Weizmann Institute of Science, Rehovot, Israel.
2
Foundation for Research on Information Technologies in Society (IT'IS), Zurich, Switzerland.
3
Swiss Federal Institute of Technology (ETH) Zurich, Zurich, Switzerland.

Abstract

BACKGROUND/AIMS:

Results from recent studies suggest that extremely low frequency magnetic fields (ELF-MF) interfere with intracellular signaling pathways related to proliferative control. The mitogen-activated protein kinases (MAPKs), central signaling components that regulate essentially all stimulated cellular processes, include the extracellular signal-regulated kinases 1/2 (ERK1/2) that are extremely sensitive to extracellular cues. Anti-phospho-ERK antibodies serve as a readout for ERK1/2 activation and are able to detect minute changes in ERK stimulation. The objective of this study was to explore whether activation of ERK1/2 and other signaling cascades can be used as a readout for responses of a variety of cell types, both transformed and non-transformed, to ELF-MF.

METHODS:

We applied ELF-MF at various field strengths and time periods to eight different cell types with an exposure system housed in a tissue culture incubator and followed the phosphorylation of MAPKs and Akt by western blotting.

RESULTS:

We found that the phosphorylation of ERK1/2 is increased in response to ELF-MF. However, the phosphorylation of ERK1/2 is likely too low to induce ELF-MF-dependent proliferation or oncogenic transformation. The p38 MAPK was very slightly phosphorylated, but JNK or Akt were not. The effect on ERK1/2 was detected for exposures to ELF-MF strengths as low as 0.15 µT and was maximal at ∼10 µT. We also show that ERK1/2 phosphorylation is blocked by the flavoprotein inhibitor diphenyleneiodonium, indicating that the response to ELF-MF may be exerted via NADP oxidase similar to the phosphorylation of ERK1/2 in response to microwave radiation.

CONCLUSIONS:

Our results further indicate that cells are responsive to ELF-MF at field strengths much lower than previously suspected and that the effect may be mediated by NADP oxidase. However, the small increase in ERK1/2 phosphorylation is probably insufficient to affect proliferation and oncogenic transformation. Therefore, the results cannot be regarded as proof of the involvement of ELF-MF in cancer in general or childhood leukemia in particular.

KEYWORDS:

ELF-MF; ERK; Extremely low frequency magnetic fields; MAPK; Mitogen-activated protein kinases; NADH oxidase

PMID:
29035881
DOI:
10.1159/000481977
[Indexed for MEDLINE]
Free full text

Supplemental Content

Full text links

Icon for S. Karger AG, Basel, Switzerland
Loading ...
Support Center