Study type: Medical/biological study (experimental study)

The Production of Tumor Necrosis Factor in Cells of Tumor-Bearing Mice after Total-Body Microwave Irradiation and Antioxidant Diet. med./bio.

Published in: Electromagn Biol Med 2004; 23 (2): 167-180

Aim of study (acc. to author)

To study the effects of repeated treatment with weak microwaves and diet with antioxidants (beta-carotene, alpha-tocopherol, and ubiquinone Q 9) on production of tumor necrosis factor in macrophages and T lymphocytes of healthy and tumor-bearing mice.

Background/further details

Feeding and microwave exposure were started on day 1 after transplantation of cancer cells. The animal cancer model was produced by subcutaneous injection of 2 x 105 Ehrlich ascites carcinoma cells in one hind limb. The mice were killed by decapitation of days 7, 14, and 30 after transplantation of cancer cells.

Endpoint

Exposure

Exposure Parameters
Exposure 1: 8.15–18 GHz

Exposure 1

Main characteristics
Frequency 8.15–18 GHz
Type
Additional info The frequency stability was better than 5%, and spectral width was better than 1 MHz. Higher harmonics were less than 25 dB.
Modulation
Modulation type cf. additional info
Additional info

Sweep frequency between 8.15 and 18 GHz with 1 s direct sweep time and 16 ms of reversed time

Exposure setup
Exposure source
Distance between exposed object and exposure source 80 cm
Setup animals kept in 25 cm x 25 cm x 45 cm plastic cages
Sham exposure A sham exposure was conducted.
Parameters
Measurand Value Type Method Mass Remarks
SAR 5 mW/kg maximum estimated - 2 mW/kg - 5 mW/kg
power density 1.6 µW/cm² maximum measured - at the center of the cage
power density 0.2 µW/cm² minimum measured - -

Reference articles

Exposed system:

Methods Endpoint/measurement parameters/methodology

Investigated system:
Investigated organ system:
Time of investigation:
  • during exposure
  • after exposure

Main outcome of study (acc. to author)

Microwave exposure and antioxidant diet stimulated production of tumor necrosis factor in cells from healthy animals. At early stages, tumor growth induced tumor necrosis factor production in cells; however, this effect decreased as tumors grew. In tumor-bearing mice exposed to microwaves, tumor necrosis factor production was higher than in unexposed tumor-bearing animals.
Oppositely, antioxidant diet induced tumor necrosis factor production in healthy animals but did not affect tumor necrosis factor secretion in tumor-bearing mice. Accordingly, prolonged treatment of tumor-bearing mice to microwaves, but not to antioxidant diet, decreased tumor growth rate and increased overall animal longevity.
These data suggest that diminished tumor growth rate due to extremely low-level microwave exposure of mice carrying tumors, at least in part, was caused by enhancement in tumor necrosis factor production and accumulation of plasma tumor necrosis factor.

Study character:

Study funded by

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