Medical/biological Study (experimental study)

Magnetic fields protect from apoptosis via redox alteration. med./biol.

PubMed Entry

Journal web site

Aim of study (according to author)
This in vitro study was performed to investigate the effects of a static magnetic field and an extremely low frequency magnetic field on intracellular oxidation-reduction, and the eventual relationship between magnetic field exposure, oxidative alteration, and apoptosis in human cancer cells.
Background/further details:
In a previous study (publication 300) the exposure of the same cell line to a static magnetic field showed a decrease in apoptosis by increasing magnetic flux density. Here, the influence of magnetic field exposure through intracellular oxidation-reduction on apoptosis should be examined.

Endpoint

• cell function: oxidation-reduction (reactive oxygen species, intracellular glutathione level)

Exposure
General category: magnetic field, static magnetic field, low frequency field, DC

Field characteristics	Parameters
field 1: LF exposure duration: 2 h, 4 h, 72 h	magnetic flux density: 0.07 mT min value magnetic flux density: 0.1 mT max value
field 2: DC/static exposure duration: 2 h, 4 h, 72 h	magnetic flux density: 0.6 mT

Exposed system:
intact cell/cell culture (in vitro)
U937 (human leukemic monocyte cell line)

Methods
Endpoint/Measurement parameters/Methodology

• cell function: oxidation-reduction (reactive oxygen species, intracellular glutathione level (flow cytometry))
• cell viability/cell division/proliferation: apoptosis (anti-apoptotic effect, apoptosis induced by pyromycin, quantified as fraction of apoptotic nuclei)

Main outcome of study (according to author)
The static magnetic field caused a strong increase of reactive oxygen species. After 2 hours of magnetic field exposure a significant decrease of intracellular glutathione levels was found and maintained thereafter, up to 72 hours.
The extremely low frequency magnetic field significantly decreased intracellular glutathione levels starting from a threshold at 0.09 mT.
Exposure to extremely low frequency magnetic field revealed an anti-apoptotic effect. The treshold for the anti-apoptotic effect corresponded with the treshold necessary to induce oxidation-reduction imbalance. Apoptosis was not affected by the exposure to extremely low frequency magnetic field in cells artificially deprived of glutathione.
The extremely low frequency magnetic field and the static magnetic field seem to exert a similar effect in terms of apoptosis, but they differ clearly in their thresholds: 0.6 mT for the static magnetic field and 0.09 mT for the extremely low frequency magnetic field.

(Study character: medical/biological study, experimental study, full/main study)

Study funded by

• not stated/none

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