Can safe and long-term exposure to extremely low frequency (50 Hz) magnetic fi elds aff ect apoptosis, reproduction, and oxidative stress?

Abstract

Purpose : To determine whether 50 Hz extremely low frequency-magnetic fi elds (ELF-MF) aff ects apoptotic processes, oxidative damage, and reproductive characteristics such as sperm count and morphology in rat testes.

Materials and methods : Thirty male Sprague-Dawley rats were used in the present study, which were divided into three groups (sham group, n = 10, and two experimental groups, n = 10 for each group). Rats in the experimental group were exposed to 100 and 500 mu T ELF-MF (2 h/day, 7 days/week, for 10 months) corresponding to exposure levels that are considered safe for humans. The same experimental procedures were applied to the sham group, but the ELF generator was turned off. Tissues from the testes were immunohistochemically stained for active (cleaved) caspase-3 in order to measure the apoptotic index by a semi-quantitative scoring system. The levels of catalase (CAT), malondialdehyde (MDA), myeloperoxidase (MPO), total antioxidative capacity (TAC), total oxidant status (TOS), and oxidative stress index (OSI) were also measured. Additionally, epididymal sperm count and sperm morphology was evaluated.

Results : There were no signifi cant diff erences in the reproductive and oxidative stress parameters between the sham group and the exposed groups (p > 0.05). While no diff erence was observed between the fi nal apoptosis score of the sham and the 100 mu T ELF-MF group (p > 0.05), the fi nal apoptosis score was higher in the 500 mu T ELF-MF exposure group than in the sham group (p < 0.05).

Conclusion : Long-term exposure to 100 mu T and 500 mu T ELF-MF did not aff ect oxidative or antioxidative processes, lipid peroxidation, or reproductive components such as sperm count and morphology in testes tissue of rats. However, long-term exposure to 500 mu T ELF-MF did aff ect active-caspase-3 activity, which is a well-known apoptotic indicator.