Medical/biological study (experimental study)

Effect of 50 Hz electromagnetic fields on the induction of heat-shock protein gene expression in human leukocytes med./bio.

By: Coulton LA, Harris PA, Barker AT, Pockley AG

Published in: Radiat Res 2004; 161 (4): 430-434

Aim of study (acc. to author)

To determine whether exposure to power-frequency magnetic fields in the range 0-100 µT either alone or concomitant with mild heating induced heat shock protein gene expression in human leukocytes. This response was compared to that induced by heat alone.

Endpoint

molecular biosynthesis: heat shock protein gene expression

Exposure

- 50/60 Hz
- magnetic field

Exposure	Parameters
Exposure 1: 50 Hz Exposure duration: continuous for 4 h	magnetic flux density: 20 µT minimum magnetic flux density: 40 µT magnetic flux density: 60 µT magnetic flux density: 80 µT magnetic flux density: 100 µT maximum

Exposure 1

Main characteristics

Frequency	50 Hz
Type	magnetic field
Waveform	sinusoidal
Exposure duration	continuous for 4 h

Exposure setup

Exposure source	coil(s)
Chamber	Wooden incubator at 37°C.
Setup	three coils with 0.25 m diameter, 0.15 m apart, stacked vertically; six 96-well plate holders were stacked in an open frame, vertically above each other between the coils; 16 samples were placed in a cluster of wells at the center of each plate.
Additional info	Additional samples were maintained in a separate incubator at 37°C for the same period. A subset was heat shocked at 42°C for the final 2 h of the 4 h experimental period which served as positive control.

Parameters

Measurand	Value	Type	Method	Mass	Remarks
magnetic flux density	20 µT	minimum	measured	-	-
magnetic flux density	40 µT	-	measured	-	-
magnetic flux density	60 µT	-	measured	-	-
magnetic flux density	80 µT	-	measured	-	-
magnetic flux density	100 µT	maximum	measured	-	-

Additional parameter details

the following field configurations were used: i) maximum field at the bottom and zero field at the top ii) maximum field at the top and zero field at the bottom

Exposed system:

blood samles

Methods Endpoint/measurement parameters/methodology

molecular biosynthesis: heat shock protein gene expression (HSP27, HSP70A or HSP70B; reverse transcriptase-PCR (RT-PCR))

Investigated system:

intact cell/cell culture
leukocytes

Time of investigation:

after exposure

Main outcome of study (acc. to author)

No evidence was found that 50 Hz power frequency magnetic fields of amplitudes 0-100 µT induce expression of genes encoding heat shock proteins in human peripheral blood leukocytes. Additionally, exposure to mild heat at 40°C did not sensitize the cells to a concomitant exposure to power-frequency magnetic fields.

Study character:

medical/biological study
experimental study
full/main study

Study funded by

EMF Biological Research Trust (EMFBRT), UK

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