Medical/biological study (experimental study)

In vitro study of the effects of ELF electric fields on gene expression in human epidermal cells med./bio.

By: Collard JF, Mertens B, Hinsenkamp M

Published in: Bioelectromagnetics 2011: 28-36

Aim of study (acc. to author)

To study the effects of extremely low frequency electric fields on gene expression in human epidermal cells.

Background/further details

Human epidermal explants were harvested from human abdominoplasty of three patients after plastic surgery. Gene expression tests were performed on days 4, 7 and 12.

Endpoint

molecular biosynthesis: gene expression

Exposure

- 40 Hz
- signals/pulses
- electric current application

Exposure	Parameters
Exposure 1: 40 Hz Modulation type: pulsed Exposure duration: (4 s on - 4 s off) for 40 min/day on 11 days	electric field strength: 275 V/m (in the explants) electric field strength: 400 V/m maximum (around the electrodes) peak current: 20 mA

Exposure 1

Main characteristics

Frequency	40 Hz
Type	electric current
Exposure duration	(4 s on - 4 s off) for 40 min/day on 11 days

Modulation

Modulation type	pulsed
Pulse width	250 ms
Pulse type	biphasic
Additional info	modulating frequency 0.125 Hz

Exposure setup

Exposure source	two platinum electrodes (50 mm x 2 mm x 0.5 mm)
Setup	six 3 mm circles of epidermis layer placed on a dermal support; electrodes in contact with the support
Sham exposure	A sham exposure was conducted.

Parameters

Measurand	Value	Type	Method	Mass	Remarks
electric field strength	275 V/m	-	measured	-	in the explants
electric field strength	400 V/m	maximum	measured	-	around the electrodes
cf. remarks	-	-	-	-	peak current: 20 mA

Reference articles

Hinsenkamp M et al. (1997): Effects of low frequency pulsed electrical current on keratinocytes in vitro
Jercinovic A et al. (1994): Low frequency pulsed current and pressure ulcer healing

Exposed system:

human epidermal explants

Methods Endpoint/measurement parameters/methodology

molecular biosynthesis: gene expression (RNA microarray (Affymetrix U133 Plus 2.0); real-time RT-PCR to validate microarray data)

Investigated system:

DNA/RNA

Time of investigation:

during exposure
after exposure

Main outcome of study (acc. to author)

After the application of extremely low frequency electric fields, the microarray analysis detected a modification of the gene expression of the epidermis cells. Particularly, four up-regulated genes (DKK1, TXNRD1, ATF3, and MME) and one down-regulated gene (MACF1) were identified which are involved in the regulation of proliferation and differentiation. Expression of these five genes was confirmed by RT-PCR. .

Study character:

medical/biological study
experimental study
full/main study

Study funded by

Belgian BioElectroMagnetic Group (BBEMG), Belgium

Lin KW et al. (2016): Exposure of ELF-EMF and RF-EMF Increase the Rate of Glucose Transport and TCA Cycle in Budding Yeast
Bouwens M et al. (2012): Low-frequency electromagnetic fields do not alter responses of inflammatory genes and proteins in human monocytes and immune cell lines
Kirschenlohr H et al. (2012): Gene expression profiles in white blood cells of volunteers exposed to a 50 Hz electromagnetic field
Hinsenkamp M et al. (2011): Bone Morphogenic Protein--mRNA upregulation after exposure to low frequency electric field
Geremia NM et al. (2007): Electrical stimulation promotes sensory neuron regeneration and growth-associated gene expression
Lupke M et al. (2006): Gene expression analysis of ELF-MF exposed human monocytes indicating the involvement of the alternative activation pathway
Henderson B et al. (2006): Gene expression profiling of human endothelial cells exposed to 50-Hz magnetic fields fails to produce regulated candidate genes
Olivares-Banuelos T et al. (2004): Differentiation of chromaffin cells elicited by ELF MF modifies gene expression pattern
Hinsenkamp M et al. (1997): Effects of low frequency pulsed electrical current on keratinocytes in vitro