Medical/biological study (experimental study)

P-selectin expression in a colon tumor model exposed by sinusoidal electromagnetic fields med./bio.

By: Tuncel H, Shimamoto F, Cirakoglu A, Korpinar MA, Kalkan T

Published in: Biomed Rep 2013; 1 (3): 389-392

Aim of study (acc. to author)

To investigate the protein expression level of P-selectin in a colon tumor model exposed to a 50 Hz-magnetic field.

Background/further details

P-selectin is a protein which functions as a cell adhesion molecule on the surfaces of endothelial cells and has a functional role in metastasis of tumor.
Rats were divided into four groups: 1.) control group (n=5), 2.) weekly rectally carcinogen administration (2 mg N-Methyl-N-Nitrosurea dissolved in 0.2 ml isotonic solution, for 10 weeks) (n=7), 3.) magnetic field exposure (n=9) and 4.) weekly rectally carcinogen administration (2 mg N-Methyl-N- Nitrosurea dissolved in 0.2 ml isotonic solution, for 10 weeks) + magnetic field exposure (n=7). The control group and the magnetic field exposure group were treated with saline solution without carcinogen in the same way.

Endpoint

molecular biosynthesis: protein expression of P-selectin in the colon

Exposure

- 50/60 Hz
- magnetic field

Exposure	Parameters
Exposure 1: 50 Hz Exposure duration: 6 hours/day for 8 month	magnetic flux density: 5 mT

Exposure 1

Main characteristics

Frequency	50 Hz
Type	magnetic field
Waveform	sinusoidal
Exposure duration	6 hours/day for 8 month

Exposure setup

Exposure source	solenoid
Chamber	rats were housed in a polycarbonate cage
Setup	12 copper solenoid coils (560 turns, resepctively) were serially connected, cores of the coils were filled with soft iron rods and tightened to increase the magnetic flux intensity, coils were vertically placed and the cages were held 1.2 cm above the coils to diminish vibration, 1 cm thick wooden plates were placed between the coils and cages to avoid heating, coils were connected to the 220 V 50 Hz sinusoidal city electric systems

Parameters

Measurand	Value	Type	Method	Mass	Remarks
magnetic flux density	5 mT	-	measured	-	-

Exposed system:

animal
rat/ Wistar
whole body

Methods Endpoint/measurement parameters/methodology

molecular biosynthesis: protein expression of P-selectin in the colon (immunohistochemistry, counterstaining with hematoxylin, semiquantitative determination of expression level)
food consumption

Investigated system:

tissue slices
colon
investigation on living organism

Time of investigation:

during exposure
after exposure

Main outcome of study (acc. to author)

No significant differences in the protein expression level of P-selectin were observed between the groups as well as no differences regarding food consumption.
The authors conclude that additional studies are required to verify the results.

Study character:

medical/biological study
experimental study
full/main study

Study funded by

Tsuchiya General Hospital, Japan
University of Istanbul, Turkey

Zhang D et al. (2011): No effects of pulsed electromagnetic fields on expression of cell adhesion molecules (integrin, CD44) and matrix metalloproteinase-2/9 in osteosarcoma cell lines
Khorseva NI et al. (2011): [Psychophysiological indicators for child users of mobile communication. Message 1: Present state of the problem]
Santini MT et al. (2006): A 50 Hz sinusoidal magnetic field does not damage MG-63 three-dimensional tumor spheroids but induces changes in their invasive properties
Santini MT et al. (2003): Effects of a 50 Hz sinusoidal magnetic field on cell adhesion molecule expression in two human osteosarcoma cell lines (MG-63 and Saos-2)
Tuncel H et al. (2002): Variable E-cadherin expression in a MNU-induced colon tumor model in rats which exposed with 50 Hz frequency sinusoidal magnetic field
Phillips JL et al. (1986): Transferrin binding to two human colon carcinoma cell lines: characterization and effect of 60-Hz electromagnetic fields