Study type: Medical/biological study (experimental study)

Differentiation of K562 cells under ELF-EMF applied at different time courses. med./bio.

Published in: Electromagn Biol Med 2010; 29 (3): 122-130

Aim of study (acc. to author)

To study the effect of different time-courses (single and repetitive exposure) of extremely low frequency electromagnetic field exposure on cell differentiation of K562 cells.

Background/further details

Additionally, cells were treated with further stressors (heat shock, 42°C and magnesium) during exposure. Cell differentiation was induced by hemin at the onset of exposure.

Endpoint

Exposure

Exposure Parameters
Exposure 1: 50 Hz
Exposure duration: continuous for 1 h
Exposure 2: 50 Hz
Exposure duration: continuous for 1 h/day for 4 days

General information

For further information on the setup see also: Tuncel, H., Shimamoto,F., Cagatay, P., Kalkan, M. T. (2002). Variable E-cadherin expression in a MNU-induced colon tumor model in rats which exposed with 50 Hz frequency sinusoidal magnetic field. Tohoku J. Exp. Med. 198:245-249
Cells were treated in the following groups: i) single EMF exposure (exposure 1) ii) repetitive EMF expsoure (exposure 2) iii) exposure 1 + magnesium iv)exposure 2 + magnesium v) exposure 1 + heat shock vi) exposure 2 + heat shock

Exposure 1

Main characteristics
Frequency 50 Hz
Type
Exposure duration continuous for 1 h
Exposure setup
Exposure source
Setup eight copper solenoids with 860 turns on an iron core connected serially to the power supply; cells kept in a constant temperature water bath placed on the solenoids
Sham exposure A sham exposure was conducted.
Parameters
Measurand Value Type Method Mass Remarks
magnetic flux density 5 mT - measured - +/- 0.1 mT

Exposure 2

Main characteristics
Frequency 50 Hz
Type
Exposure duration continuous for 1 h/day for 4 days
Exposure setup
Exposure source
Sham exposure A sham exposure was conducted.
Parameters
Measurand Value Type Method Mass Remarks
magnetic flux density 5 mT - measured - +/- 0.1 mT

Reference articles

  • Öztas B et al. (2004): Influence of 50 Hz frequency sinusoidal magnetic field on the blood-brain barrier permeability of diabetic rats.

Exposed system:

Methods Endpoint/measurement parameters/methodology

Investigated system:
Time of investigation:
  • during exposure
  • after exposure

Main outcome of study (acc. to author)

The data showed that single exposure to an extremely low frequency electromagnetic field resulted in a decrease in cell differentiation, while extremely low frequency electromagnetic field applied everyday for 1 h caused an increase in cell differentiation (compared with controls). The effect of co-stressors (magnesium and heat-shock) was similar to the results obtained by extremely low frequency electromagnetic field exposure alone.
Extremely low frequency electromagnetic field exposure increased reactive oxygen species levels in K562 cells not treated with hemin. However, electromagnetic field exposure did not change reactive oxygen species levels of hemin treated cells indicating that reactive oxygen species were not the cause for the decrease or increase of cell differentiation.
In conclusion, these findings imply that the time-course of exposure is an important parameter determining the physiological response of cells to extremely low frequency electromagnetic fields.

Study character:

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