Medical/biological study (experimental study)

Effects of electromagnetic fields on Reelin and Dab1 expression in the developing cerebral cortex med./bio.

By: Hemmati M, Mashayekhi F, Firouzi F, Ashori M, Mashayekhi H

Published in: Neurol Sci 2014; 35 (8): 1243-1247

To investigate the effects of exposure to a 50 Hz-magnetic field on total protein concentration as well as protein expression of reelin and Dab1 in the developing cortex of mice.

Reelin is a protein which helps to regulate processes of neural migration and positioning in the developing brain via cell-cell interactions. Disabled-1 (Dab1) is an important regulator of Reelin signalling.
Pregnant mice were divided into three groups (n=10 per group): 1.) cage control (embryos n=42), 2.) sham exposure group (embryos n=48) and 3.) exposure group (embryos n= 56). Exposure or sham exposure took place from gestational day 15-17. Dams were killed on gestational day 18 and cortices of embryos were collected for examinations.

effects on the neurological system: protein expression of Reelin and Dab1 in the cortex

Exposure	Parameters
Exposure 1: 50 Hz Exposure duration: 5 hours/day for 3 consecutive days	magnetic flux density: 0.5 mT

Frequency	50 Hz
Type	magnetic field
Exposure duration	5 hours/day for 3 consecutive days

Exposure source	solenoid
Setup	urban electric line adaptor 220 V and 10 A was used for minimizing the heat production, EMF emitter set including bobbin (80 x 10), wires and metal nucleuses was put in the bottom of hatchery machine in a metal lacuna, calibration of the exposure facility was performed to confirm uniform distribution of the magnetic field intensity where mice were kept, temperature and humidity were monitored continuously
Sham exposure	A sham exposure was conducted.

Measurand	Value	Type	Method	Mass	Remarks
magnetic flux density	0.5 mT	-	-	-	-

Exposed system:

effects on the neurological system: protein expression of Reelin and Dab1 in the cortex (Western blot); total protein concentration (Bradford protein assay)

Investigated system:

Time of investigation:

No significant differences between the groups were seen regarding the total protein concentration. Additionally, no significant differences in the protein expression were seen between the cage control and the sham exposed group. However, in cortices from the exposure group the protein expression of Reelin and Dab1 was significantly increased compared to the cage control and the sham exposed group.
The authors conclude that exposure to a 50 Hz-magnetic field could influence the protein expression of Reelin and Dab1 in the developing cortex of mice.

Study character:

Zheng Y et al. (2019): Effects of exposure to extremely low frequency electromagnetic fields on hippocampal long-term potentiation in hippocampal CA1 region
Balassa T et al. (2013): Changes in synaptic efficacy in rat brain slices following extremely low-frequency magnetic field exposure at embryonic and early postnatal age
Fournier NM et al. (2012): Neurodevelopmental anomalies of the hippocampus in rats exposed to weak intensity complex magnetic fields throughout gestation
Roda O et al. (2011): Biological effects of low-frequency pulsed magnetic fields on the embryonic central nervous system development. A histological and histochemical study
St-Pierre LS et al. (2008): Behavioral Changes in Adult Rats After Prenatal Exposures to Complex, Weak Magnetic Fields
McKay BE et al. (2003): Radial maze proficiency of adult Wistar rats given prenatal complex magnetic field treatments
Yu MC et al. (1993): Effects of 60 Hz electric and magnetic fields on maturation of the rat neopallium
Gona AG et al. (1993): Effects of 60 Hz electric and magnetic fields on the development of the rat cerebellum [see comments]