Exposure of rats to extremely low-frequency electromagnetic fields (ELF-EMF) alters cytokines production

Abstract

Investigations indicate a potential link between exposure to extremely low-frequency electromagnetic field (ELF-EMF) and some cancers. Carcinogenesis of ELF-EMF may be mediated by effect on the immune system. During an immune response, naïve T cells differentiate to effector type 1 helper T cells (T_H1), T_H2, or T_H17 subsets according to existence of different cytokines and T_H1 is important in defense against tumors. Therefore, it will be reasonable to test whether ELF-EMF can change cytokines like interferon gamma (IFN-γ), interleukin-4 (IL-4), IL-6, and IL-12 that regulate T_H1/T_H2/T_H17 balance. Forty adult male rats were randomly separated into ELF-EMF-exposed and sham-exposed control groups. The ELF-EMF group was exposed to a flux density of 100 μT, frequency 50 Hz, 2 h/day for 3 months. The controls were placed in identical chamber without ELF-EMF. The results showed there were no significant differences between the mean mass of rats, thymuses, and spleens in ELF-EMF exposed group compared with controls. Serum IL-12 level was decreased from 418 ± 47 pg/ml in controls to 300 ± 23 pg/ml (p < 0.05) in ELF-EMF-exposed group. Phytohemagglutinin activated of in vitro production of IL-6 by the whole spleen culture (1356 ± 92 pg/ml) and total blood culture (418 ± 40 pg/ml) of ELF-EMF-exposed rats were higher (p < 0.001) comparing with controls (905 ± 74 pg/ml), (182 ± 26 pg/ml), respectively. However, the levels of IFN-γ, IL-4, and IL-6 of serum and IFN-γ, IL-4, and IL-12 in spleen culture and total blood culture of two groups were not significantly different. It seems that ELF-EMF may change T_H1/T_H2/T_H17 balance toward down regulation of T_H1 and upregulation T_H17 type responses.

Keywords::

• Cytokine
• T-lymphocytes
• Electromagnetic fields
• Interleukin
• Interferon

Acknowledgements

The authors would like to express their gratitude to the staff of the Research Center for Molecular Medicine (Hamadan Iran) for helping them carry out this project, especially Mr. Fazli and Mrs. Ghiasvand. This project was funded by the research deputy of Hamadan University of Medical Sciences (Hamadan Iran).

Declaration of interest The authors have no conflict of interest.