Medical/biological study (experimental study)

Potential protection of green tea polyphenols against 1800 MHz electromagnetic radiation-induced injury on rat cortical neurons med./bio.

By: Liu ML, Wen JQ, Fan YB

Published in: Neurotox Res 2011; 20 (3): 270-276

To study the possible protective effects of green tea polyphenols against electromagnetic irradiation-induced injury in the cultured rat cortical neurons.

After exposure, the cells were treated with green tea polyphenols for 4 h (different concentrations). Green tea polyphenols have been shown to have a antioxidant capacity, anti-proliferative ability, and anti-carcinogenic properties in neurodegenerative diseases.

Exposure	Parameters
Exposure 1: 1,800 MHz Exposure duration: continuous for 6 x 2 h/day on 2 days	electric field strength: 28.67 V/m minimum (+/- 0.88 V/m in the cell culture plates) electric field strength: 92.67 V/m minimum (+/- 1.2 V/m in the cell culture plates)

Exposure source	cellular phone Nokia 6060v
Chamber	incubator with a constant temperature of 37°C, 95% air and 5% CO₂
Setup	mobile phone placed above the cell culture plates with the antenna positioned over their center
Sham exposure	A sham exposure was conducted.
Additional info	for sham exposure the mobile phone was in stand-by mode

Measurand	Value	Type	Method	Mass	Remarks
electric field strength	28.67 V/m	minimum	-	-	+/- 0.88 V/m in the cell culture plates
electric field strength	92.67 V/m	minimum	-	-	+/- 1.2 V/m in the cell culture plates

Exposed system:

Investigated system:

Time of investigation:

The data showed that the mobile phone exposure for 24 h induced marked neuronal cell death in the TUNEL assay and a decreased cell viability in the MTT assay. Protective effects of green tea polyphenols (10 µM) on the injured cortical neurons were demonstrated by testing the content of Bax. The mobile phone irradiation-induced increases in the content of active Bax were inhibited significantly by green tea polyphenols, while the contents of total Bax had no marked changes after the treatment of green tea polyphenols. The mobile phone exposure increased the protein expression of Hsp70 compared with the sham exposed control.
The results suggest a neuroprotective effect of green tea polyphenols against the mobile phone irradiation-induced injury in the cultured rat cortical neurons.

Study character:

Xu S et al. (2010): Exposure to 1800 MHz radiofrequency radiation induces oxidative damage to mitochondrial DNA in primary cultured neurons
Ozgur E et al. (2010): Mobile phone radiation-induced free radical damage in the liver is inhibited by the antioxidants N-acetyl cysteine and epigallocatechin-gallate
Del Vecchio G et al. (2009): Effect of radiofrequency electromagnetic field exposure on in vitro models of neurodegenerative disease
Zhao TY et al. (2007): Exposure to cell phone radiation up-regulates apoptosis genes in primary cultures of neurons and astrocytes
Kim MJ et al. (2004): Green tea catechins protect rats from microwave-induced oxidative damage to heart tissue
Kim MJ et al. (2002): Effects of green tea catechin on enzyme activities and gene expression of antioxidative system in rat liver exposed to microwaves