Medical/biological study (experimental study)

Weak electromagnetic fields (50 Hz) elicit a stress response in human cells med./bio.

By: Tokalov SV, Gutzeit HO

Published in: Environ Res 2004; 94 (2): 145-151

Aim of study (acc. to author)

To investigate the effects of extremely low frequency electromagnetic fileds (ELF EMF) alone and in combination with thermal stress on the expression of heat shock protein genes in human myeloid leukemia (HL-60) cells in vitro.

Endpoint

molecular biosynthesis: expression of heat shock genes

Exposure

Exposure	Parameters
Exposure 1: 50 Hz Exposure duration: continuous for 30 min	magnetic flux density: 10 µT minimum (20 µT, 40 µT, 60 µT, 80 µT, 100 µT and 140 µT +/- 0.4 µT.)

Exposure 1

Main characteristics

Frequency	50 Hz
Type	magnetic field
Waveform	sinusoidal
Exposure duration	continuous for 30 min

Exposure setup

Exposure source	Merritt coils, pls see reference article.
Chamber	Plastic chamber maintained at 37°C and/or 43°C.
Setup	The chamber containing the samples was placed in the center of the coils.
Sham exposure	A sham exposure was conducted.

Parameters

Measurand	Value	Type	Method	Mass	Remarks
magnetic flux density	10 µT	minimum	cf. remarks	-	20 µT, 40 µT, 60 µT, 80 µT, 100 µT and 140 µT +/- 0.4 µT.

Additional parameter details

Stray MF: 1 µT max value.

Reference articles

Junkersdorf B et al. (2000): Electromagnetic fields enhance the stress response at elevated temperatures in the nematode Caenorhabditis elegans

Exposed system:

intact cell/cell culture
HL-60 (human acute myeloid leukaemia cells)

Methods Endpoint/measurement parameters/methodology

molecular biosynthesis: expression of heat shock genes (RT-PCR, electrophoresis)

Investigated system:

DNA/RNA
genes encoding for heat shock proteins

Time of investigation:

after exposure

Main outcome of study (acc. to author)

The results of this study show that extremely low frequency electromagnetic fields are capable to induce the expression of genes encoding for heat shock proteins (in particular HSP 70 A, B, and C). This reaction is enhanced by a simultanious thermal stress (43°C for 30 minutes). These effect was found at all different flux densitys tested with a maximum at flux density of 60-80 µT.

Study character:

medical/biological study
experimental study
full/main study

Study funded by

Deutsche Forschungsgemeinschaft (DFG; German Research Foundation)

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Basile A et al. (2011): Exposure to 50 Hz electromagnetic field raises the levels of the anti-apoptotic protein BAG3 in melanoma cells
Mannerling AC et al. (2010): Effects of 50-Hz magnetic field exposure on superoxide radical anion formation and HSP70 induction in human K562 cells
Garip AI et al. (2010): Effect of ELF-EMF on number of apoptotic cells; correlation with reactive oxygen species and HSP
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