Study type: Medical/biological study (experimental study)

Electromagnetic field treatment protects against and reverses cognitive impairment in Alzheimer's disease mice. med./bio.

Published in: J Alzheimers Dis 2010; 19 (1): 191-210

Aim of study (acc. to author)

To elucidate effects of long-term electromagnetic field exposure (7-9 months) on Alzheimer's disease-like cognitive impairment and neuropathology, the authors exposed Alzheimer's disease transgenic mice and littermate non-transgenic mice to the same radiofrequency electromagnetic field level that the human head is exposed to during two one hour periods of mobile phone use (918 MHz; 250 mW/kg) each day.

Background/further details

One experiment was performed with yound adult mice and one experiment was performed with aged adult mice. In the young adult mice long-term study, a total of 24 transgenic mice and non-transgenic littermates (aged 2-2.5 months) were divided into the following four groups (n=6 per group): 1) transgenic control group, 2) transgenic exposure group, 3) non-transgenic control group and 4) non-transgenic exposure group. In the aged adult mice long-term study 12 transgenic and 16 non-transgenic mice were used (aged 4 months; n=5-8 mice/group).
Parental mice consisted of a mixed genetic background providing offspring consisting of transgenic and non-transgenic genotypes (i.e. non-transgenic littermates).
A modified cognitive interference task was performed that is utilized in humans to differentiate aged non-demented, mild cognitive impairment, and Alzheimer's disease patients from one another.
Additional groups of mice of the same genotypes were used for an acute temperature study (brain and rectal temperature were measured).
In vitro studies with hippocampus tissues were also performed to investigate amyloid beta protein aggregation.

Endpoint

Exposure

Exposure Parameters
Exposure 1: 918 MHz
Exposure duration: 2 times (early morning and late afternoon) 1 h/day for 9.5 months
young adult - long term exposure
  • SAR: 250 mW/kg
Exposure 2: 918 MHz
Exposure duration: 2 times (early morning and late afternoon) 1 h/day for 8.5 months
aged adult - long term exposure
  • SAR: 250 mW/kg
Exposure 3: 918 MHz
Exposure duration: 2 times (early morning and late afternoon) 1 h
  • SAR: 250 mW/kg
Exposure 4: 918 MHz
Exposure duration: 2 times (early morning and late afternoon) 1 h for 6 days
in vitro study
  • SAR: 250 mW/kg

General information

for the long term in vivo studies animals were treated in four groups: i) transgenetic control ii) transgenetic with EMF exposure iii) non-transgenetic control iv) non-transgenetic with EMF exposure

Exposure 1

Main characteristics
Frequency 918 MHz
Type
Exposure duration 2 times (early morning and late afternoon) 1 h/day for 9.5 months
Additional info young adult - long term exposure
Exposure setup
Exposure source
Distance between exposed object and exposure source 26 cm
Setup animal cages arranged circularly around the centrally located antenna inside a 4 m x 4 m x 4 m Faraday cage
Parameters
Measurand Value Type Method Mass Remarks
SAR 250 mW/kg - - whole body -

Exposure 2

Main characteristics
Frequency 918 MHz
Type
Exposure duration 2 times (early morning and late afternoon) 1 h/day for 8.5 months
Additional info aged adult - long term exposure
Exposure setup
Exposure source
Distance between exposed object and exposure source 26 cm
Parameters
Measurand Value Type Method Mass Remarks
SAR 250 mW/kg - - whole body -

Exposure 3

Main characteristics
Frequency 918 MHz
Type
Exposure duration 2 times (early morning and late afternoon) 1 h
Additional info aged adult - acute exposure
Exposure setup
Exposure source
Distance between exposed object and exposure source 26 cm
Sham exposure A sham exposure was conducted.
Parameters
Measurand Value Type Method Mass Remarks
SAR 250 mW/kg - - whole body -

Exposure 4

Main characteristics
Frequency 918 MHz
Type
Exposure duration 2 times (early morning and late afternoon) 1 h for 6 days
Additional info in vitro study
Exposure setup
Exposure source
Distance between exposed object and exposure source 26 cm
Sham exposure A sham exposure was conducted.
Parameters
Measurand Value Type Method Mass Remarks
SAR 250 mW/kg - - whole body -

Exposed system:

Methods Endpoint/measurement parameters/methodology

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

Main outcome of study (acc. to author)

The data showed that long-term intermittent electromagnetic field exposure: 1) protects young adult transgenic mice from later cognitive impairment, 2) reverses cognitive impairment and Alzheimer's disease-like brain pathology in older transgenic mice, and 3) increases cognitive performance of normal non-transgenic mice.
In Alzheimer's disease mice, long-term electromagnetic field exposure reduced brain amyloid beta protein deposition through amyloid beta protein anti-aggregation actions (demonstrated in in vitro and in vivo studies) and increased brain temperature during exposure periods. The analysis of oxidative markers from brains of mice in the young adult long-term study revealed minimal or no EMF-induced effects on DNA repair enzymes, antioxidant enzymes, or extent of protein oxidative damage.
The authors propose several interrelated mechanisms of electromagnetic field action, including increased amyloid beta protein clearance from the brains of Alzheimer's disease mice, increased neuronal activity, and increased cerebral blood flow. Although caution should be taken in extrapolating these mouse studies to humans, the authors conclude that electromagnetic field exposure may represent a non-invasive, non-pharmacologic therapeutic against Alzheimer's disease and an effective memory-enhancing approach in general.

Study character:

Study funded by

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