Medical/biological study (experimental study)

Neuroprotective effect of ginseng against alteration of calcium binding proteins immunoreactivity in the mice hippocampus after radiofrequency exposure med./bio.

By: Maskey D, Lee JK, Kim HR, Kim HG

Published in: Biomed Res Int 2013: 812641

Aim of study (acc. to author)

To examine the potential protective effect of ginseng on the hippocampus of mice exposed to a radiofrequency electromagnetic field.

Background/further details

Three groups of mice were examined (n=10 per group): 1.) sham exposure, 2.) exposure and 3.) exposure + 30mg/kg ginseng extract.
Calcium binding proteins like calbindin D28k, parvalbumin and calretinin, play an important role in maintaining the intracellular calcium homeostasis. These proteins are specifically distributed in the central nervous system. Ginseng is a widely used herbal medicine with a possibly protective effect on the central nervous system. Therefore, the immunoreactivity of calcium binding proteins in the hippocampus of mice was examined with and without an administration of ginseng extract.

Endpoint

effects on the neurological system: immunoreactivity of calcium binding proteins in the brain

Exposure

- 835 MHz
- CDMA
- mobile communications
- mobile phone

Exposure	Parameters
Exposure 1: 835 MHz Exposure duration: 5 h/day for 30 consecutive days	SAR: 1.6 W/kg mean electric field strength: 59.56 V/m power: 2.5 W (output power, simulated)

Exposure 1

Main characteristics

Frequency	835 MHz
Type	electromagnetic field
Exposure duration	5 h/day for 30 consecutive days

Exposure setup

Exposure source	horn antenna
Chamber	mice were exposed in a standard mouse cage of 22 inches (remark EMF-Portal: ca. 56 cm)
Sham exposure	A sham exposure was conducted.

Parameters

Measurand	Value	Type	Method	Mass	Remarks
SAR	1.6 W/kg	mean	-	-	-
electric field strength	59.56 V/m	-	calculated	-	-
power	2.5 W	-	cf. remarks	-	output power, simulated

Reference articles

Maskey D et al. (2010): Chronic 835-MHz radiofrequency exposure to mice hippocampus alters the distribution of calbindin and GFAP immunoreactivity

Exposed system:

animal
mouse/ICR
whole body

Methods Endpoint/measurement parameters/methodology

morphol./histopathol. changes: histopathological changes in the brain (microscopy)
effects on the neurological system: immunoreactivity of calcium binding proteins (calbindin D28k, parvalbumin, calretinin) (immunohistochemistry, microscopy)

Investigated system:

tissue slices
hippocampus

Investigated organ system:

brain/CNS

Time of investigation:

after exposure

Main outcome of study (acc. to author)

Significant decreases in the intensity of the immunoreactivities regarding calbindin D28k, parvalbumin and calretinin were observed in the exposure group without ginseng when compared to the control group in most of the hippocampal areas. However, no significant differences were observed between the exposure group with ginseng administration and the control group.
Additionally, histopathological changes occurred: In the hippocampus of exposed mice without ginseng, the dendritic arborization decreased compared to the control group, but not in exposed mice with ginseng administration.
The authors conclude that a radiofrequency electromagnetic field could disturb the calcium homeostasis via changing the immunoreactivity of calcium binding proteins in the hippocampus of mice and that ginseng could have a protective effect.

Study character:

medical/biological study
experimental study
full/main study

Study funded by

Korea Ginseng Corporation, Korea
Korean Society of Ginseng (KSG), Korea

Maskey D et al. (2012): Calcium-binding proteins and GFAP immunoreactivity alterations in murine hippocampus after 1 month of exposure to 835MHz radiofrequency at SAR values of 1.6 and 4.0 W/kg
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