To examine the effects of catechin and epicatechin on cognitive performance and oxidative stress in mice exposed to a 50 Hz magnetic field.
Male mice were randomly divided into nine groups (n=10 per group): 1) sham exposure, 2) magnetic field + saline solution, 3) magnetic field + 20 mg/kg body weight piracetam, 4) magnetic field + 30 mg/kg body weight epicatechin, 5) magnetic field + 60 mg/kg body weight epicatechin, 6) magnetic field + 90 mg/kg body weight epicatechin, 7) magnetic field + 30 mg/kg body weight catechin, 8) magnetic field + 60 mg/kg body weight catechin, and 9) magnetic field + 90 mg/kg body weight catechin. All substances were administered orally.
Catechin and epicatechin are flavonoids with an antioxidant effect and are widely distributed in tea, fruits and vegetables. Piracetam is a medication which is prescribed against dementia and cognitive deficits.
Exposure duration: 8 hours/day for 30 consecutive days
|Exposure duration||8 hours/day for 30 consecutive days|
|Chamber||mice were exposed in a well ventilated box made from acryl glass (14 cm x 10 cm x 12 cm)|
|Setup||exposure box was placed in the middle of a pair of coils with a non-magnetic holder; the magnetic field was homogeneous over time and uniformi; temperature was kept constant at 23 ± 0.5°C|
|Sham exposure||A sham exposure was conducted.|
|magnetic flux density||0.2 mT||unspecified||measured||-||-|
Exposed mice (group 2) showed a significantly increased body weight compared to sham exposed ones (group 1). Learning and memory abilities were impaired in exposed mice when compared to sham exposed mice as shown by a significantly decrease in the residence time in the forth quadrant in the morris water maze. The enzyme activities of the superoxide dismutase and the catalase were significantly decreased in exposed mice in comparison to sham exposed ones while the level of nitric oxide was significantly increased.
The administration of piracetam (group 3), epicatechin (groups 4-6) and catechin (group 7-9) reversed the exposure induced effects partially. However, different concentrations of epicatechin and catechin showed the best efficacy in the different experiments.
The authors conclude that the exposure to a 50 Hz magnetic fields could impair learning and memory abilities and induces oxidative stress in the brain of mice and that catechin as well as epicatechin could attenuate the expoure induced effects.