Medical/biological study (experimental study)

Effect of exposure to 1,800 MHz electromagnetic fields on heat shock proteins and glial cells in the brain of developing rats med./bio.

By: Watilliaux A, Edeline JM, Leveque P, Jay TM, Mallat M

Published in: Neurotox Res 2011; 20 (2): 109-119

Aim of study (acc. to author)

To study whether GSM 1800 MHz electromagnetic fields affect immature rodent brains when applied at various stages of postnatal development.

Background/further details

Young rats, exposed to electromagnetic fields on postnatal days 5 (n=6), 15 (n=5) or 35 (n=6), were compared to sham exposed littermate rats (n=6 at all ages).

Endpoint

effects on the neurological system: stress reaction and glial activation in the immature brain

Exposure

- mobile communications
- GSM

Exposure	Parameters
Exposure 1: 1,800 MHz Modulation type: pulsed Exposure duration: continuous for 2 h on postnatal day 5, 15 or 35	SAR: 0.13 W/kg mean (whole body) (on postnatal day 35) SAR: 0.63 W/kg mean (whole body) (on postnatal day 15) SAR: 1.2 W/kg mean (whole body) (on postnatal day 5) SAR: 1.7 W/kg mean (brain) (on postnatal day 35) SAR: 2.2 W/kg mean (brain) (on postnatal day 15) SAR: 2.5 W/kg mean (brain) (on postnatal day 5)

Exposure 1

Main characteristics

Frequency	1,800 MHz
Type	electromagnetic field
Exposure duration	continuous for 2 h on postnatal day 5, 15 or 35

Modulation

Modulation type	pulsed
Duty cycle	12.5 %
Repetition frequency	217 Hz

Exposure setup

Exposure source	loop antenna
Setup	loop antenna consisting of a printed circuit with two metallic lines engraved in a dielectric epoxy resin substrate with a 1 mm wide line forming loop at one end, which was placed close to the animal's head
Sham exposure	A sham exposure was conducted.

Parameters

Measurand	Value	Type	Method	Mass	Remarks
SAR	0.13 W/kg	mean	calculated	whole body	on postnatal day 35
SAR	0.63 W/kg	mean	calculated	whole body	on postnatal day 15
SAR	1.2 W/kg	mean	calculated	whole body	on postnatal day 5
SAR	1.7 W/kg	mean	calculated	brain	on postnatal day 35
SAR	2.2 W/kg	mean	calculated	brain	on postnatal day 15
SAR	2.5 W/kg	mean	calculated	brain	on postnatal day 5

Reference articles

Leveque P et al. (2004): Dosimetric Analysis of a 900-MHz Rat Head Exposure System
Dubreuil D et al. (2003): Head-only exposure to GSM 900-MHz electromagnetic fields does not alter rat's memory in spatial and non-spatial tasks
Dubreuil D et al. (2002): Does head-only exposure to GSM-900 electromagnetic fields affect the performance of rats in spatial learning tasks?

Exposed system:

animal
rat/Wistar
partial body: head (mainly)

Methods Endpoint/measurement parameters/methodology

effects on the neurological system: stress reaction and glial activation in the immature brain (expression of heat shock proteins (Hsp60, Hsc70, Hsp70, Hsp90) and expression of GFAP, serine racemase, two glutamate transporters (GLT1 and GLAST) and CD68; Western blot); glial activation (expression of CD68 and CD11; immunocytochemistry)

Investigated system:

isolated bio./chem. substance
tissue slices
brain tissue homogenates and lysates

Investigated organ system:

brain/CNS

Time of investigation:

after exposure

Main outcome of study (acc. to author)

The GSM signal had no significant effect on the abundance of Hsp60, Hsc70 or Hsp90, of serine racemase, glutamate transporters (GLT1 and GLAST), or of GFAP. Immunohistochemical detection of CD68 antigen in brain sections from sham exposed and exposed animals did not reveal any differences in the morphology or distribution of microglial cells.
These data provide no evidence for acute cell stress or glial reactions indicative of early neural cell damage in developing brains exposed to 1800 MHz signals.

Study character:

medical/biological study
experimental study
full/main study

Study funded by

Centre National de la Recherche Scientifique (CNRS; French National Center for Scientific Research), France
Institut national de la santé et de la recherche médicale (INSERM), France
Fondation Santé et Radiofréquences, France
Institut National de L'Environnement Industriel et des Risques (INERIS), France
Université Pierre et Marie Curie (UPMC), Paris, France

Erdem Koc G et al. (2016): Neuroprotective effects of melatonin and omega-3 on hippocampal cells prenatally exposed to 900 MHz electromagnetic fields
Razavinasab M et al. (2016): Maternal mobile phone exposure alters intrinsic electrophysiological properties of CA1 pyramidal neurons in rat offspring
Deshmukh PS et al. (2015): Cognitive impairment and neurogenotoxic effects in rats exposed to low-intensity microwave radiation
Kesari KK et al. (2014): Effect of 3G Cell Phone Exposure with Computer Controlled 2-D Stepper Motor on Non-thermal Activation of the hsp27/p38MAPK Stress Pathway in Rat Brain
Haghani M et al. (2013): Maternal mobile phone exposure adversely affects the electrophysiological properties of Purkinje neurons in rat offspring
Yang XS et al. (2012): Exposure to 2.45 GHz electromagnetic fields elicits an HSP-related stress response in rat hippocampus
Aldad TS et al. (2012): Fetal Radiofrequency Radiation Exposure From 800-1900 Mhz-Rated Cellular Telephones Affects Neurodevelopment and Behavior in Mice
Orendacova J et al. (2011): Effects of short-duration electromagnetic radiation on early postnatal neurogenesis in rats: Fos and NADPH-d histochemical studies
Sonmez OF et al. (2010): Purkinje cell number decreases in the adult female rat cerebellum following exposure to 900 MHz electromagnetic field
Jorge-Mora T et al. (2010): Exposure to 2.45 GHz microwave radiation provokes cerebral changes in induction of HSP-90 a/ß.heat shock protein in rat
Maskey D et al. (2010): Chronic 835-MHz radiofrequency exposure to mice hippocampus alters the distribution of calbindin and GFAP immunoreactivity
Ragbetli MC et al. (2010): The effect of mobile phone on the number of Purkinje cells: a stereological study
Bas O et al. (2009): Chronic prenatal exposure to the 900 megahertz electromagnetic field induces pyramidal cell loss in the hippocampus of newborn rats
Ragbetli MC et al. (2009): Effect of prenatal exposure to mobile phone on pyramidal cell numbers in the mouse hippocampus: a stereological study
Orendacova J et al. (2009): Immunohistochemical study of postnatal neurogenesis after whole-body exposure to electromagnetic fields: evaluation of age- and dose-related changes in rats
Finnie JW et al. (2009): Heat shock protein induction in fetal mouse brain as a measure of stress after whole of gestation exposure to mobile telephony radiofrequency fields
Bas O et al. (2009): 900 MHz electromagnetic field exposure affects qualitative and quantitative features of hippocampal pyramidal cells in the adult female rat
Odaci E et al. (2008): Effects of prenatal exposure to a 900 MHz electromagnetic field on the dentate gyrus of rats: a stereological and histopathological study
Paulraj R et al. (2006): Protein kinase C activity in developing rat brain cells exposed to 2.45 GHz radiation
Lee JS et al. (2005): Subchronic exposure of hsp70.1-deficient mice to radiofrequency radiation
Mausset-Bonnefont AL et al. (2004): Acute exposure to GSM 900-MHz electromagnetic fields induces glial reactivity and biochemical modifications in the rat brain
Mausset AL et al. (2001): Effects of radiofrequency exposure on the GABAergic system in the rat cerebellum: clues from semi-quantitative immunohistochemistry
Berman E et al. (1984): Decreased body weight in fetal rats after irradiation with 2450-MHz (CW) microwaves
Berman E et al. (1984): Growth and development of mice offspring after irradiation in utero with 2,450-MHz microwaves