Medical/biological study (experimental study)

Induced mitogenic activity in AML-12 mouse hepatocytes exposed to low-dose ultra-wideband electromagnetic radiation med./bio.

By: Dorsey WC, Ford BD, Roane L, Haynie DT, Tchounwou PB

Published in: Int J Environ Res Public Health 2005; 2 (1): 24-30

Aim of study (acc. to author)

To study the effect of ultra-wideband (UWB) irradiation on mitogenic activity in AML-12 mouse hepatocytes.

Background/further details

On the day of the experiment, medium was replaced with fresh hepatocyte growth medium (HGM) or serum-free growth medium (SFM). In some experiments, medium was supplemented with insulin-transferrin-selenium (a mitogen).

Endpoint

cell viability/cell division/proliferation: cell viability

Exposure

- UWB

Exposure	Parameters
Exposure 1: 1 kHz–100 MHz Modulation type: pulsed Exposure duration: continuous for 2 h	electric field strength: 20 kV/m (5-20 kV/m)

Exposure 1

Main characteristics

Frequency	1 kHz–100 MHz
Type	electromagnetic field
Waveform	pulsed
Charakteristic	guided field
Exposure duration	continuous for 2 h

Modulation

Modulation type	pulsed
Pulse width	10 ns
Repetition frequency	1 kHz

Exposure setup

Exposure source	GTEM cell
Chamber	The exposure facility was shielded with copper and steel plating and contained a GTEM cell located in a temperature controlled room (23°C) and a pulser that was triggered from a second copper mesh, RF-shielded enclosure.
Setup	Microtiter plates were placed horizontally inside the GTEM cell.
Sham exposure	A sham exposure was conducted.

Parameters

Measurand	Value	Type	Method	Mass	Remarks
electric field strength	20 kV/m	-	measured	-	5-20 kV/m

Measurement and calculation details

A D-dot probe connected to a 6 GHz digital storage oscilloscope in the second enclosure was used to monitor pulse characteristics in the GTEM cell.

Exposed system:

intact cell/cell culture
AML-12 (alpha mouse liver-12) hepatocytes

Methods Endpoint/measurement parameters/methodology

Investigated system:

isolated bio./chem. substance
intact cell/cell culture
cell lysates

Time of investigation:

after exposure

Main outcome of study (acc. to author)

Low-dose UWB irradiation caused a mitogenic response in AML-12 mouse hepatocytes. During the post-exposure period of 8-24 h, a dose-dependent increase in cell viability was found in in both serum-treated and serum free medium -treated hepatocytes.
Cyclin A protein was induced in UWB exposed hepatocytes, suggesting that increased activity in the MTT assay after exposure was due to cell proliferation.
This study indicates that UWB irradiation has a mitogenic effect on AML-12 mouse hepatocytes.

Study character:

medical/biological study
experimental study
full/main study

Study funded by

Air Force Office of Scientific Research (AFOSR), USA
Grambling State University, Grambling, Louisiana, USA

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