Effects of Extremely Low Frequency Magnetic Field (ELF-MF) on Formalin Induced Chronic Pain in Mice

Background: Effects of Extremely Low Frequency Magnetic Field) ELF-MF (in the elevation of blood sugar, cholesterol, triglyceride and reduction of withdrawal syndrome of morphine have been reported so far. Since pain is one of the main concerns in medicine and usually analgesic drugs are not much beneficial or cause considerable side effects, the present project was carried out with the aim of evaluating the effects of (ELF-MF (in chronic pain using formalin test in mice. Materials & Methods: In this experimental study, thirty two adult male mice were used and divided into 4 groups (n = 8). Three groups of animals exposed daily for thirty minutes to 25, 50, 75 HZ (intense 250 μT) of electromagnet field for one week, respectively and one group considered as control with no exposure. At the end of a week, formalin test was performed. Responses to formalin were observed for sixty minutes. The results were compared between tests and control group. Findings: In acute phase of formalin test, ELF-MF reduced significantly the pain scores following formalin injection at all 3 frequencies, especially at 25 and 50 HZ (p < 0.001) rather 75 HZ (p < 0.05). In chronic phase of formalin test, ELF-MF reduced pain scores at 25 and 50 HZ (p < 0.05). However, the most effective responses were obtained at 50 HZ frequency. Conclusion: The findings show that ELF-MF is effective to reduce formalin induced chronic pain in mice at both acute and chronic phases.

Effects of Single and Repeated Exposure to a 50-Hz 2-mT Electromagnetic Field on Primary Cultured Hippocampal Neurons

The prevalence of domestic and industrial electrical appliances has raised concerns about the health risk of extremely low-frequency magnetic fields（ELF-MFs）. At present, the effects of ELF-MFs on the central nervous system are still highly controversial, and few studies have investigated its effects on cultured neurons. Here, we evaluated the biological effects of different patterns of ELF-MF exposure on primary cultured hippocampal neurons in terms of viability, apoptosis, genomic instability,and oxidative stress. The results showed that repeated exposure to 50-Hz 2-mT ELF-MF for 8 h per day after different times in culture decreased the viability and increased the production of intracellular reactive oxidative species in hippocampal neurons. The mechanism was potentially related to the up-regulation of Nox2 expression.Moreover, none of the repeated exposure patterns had significant effects on DNA damage, apoptosis, or autophagy, which suggested that ELF-MF exposure has no severe biological consequences in cultured hippocampal neurons.

Extremely low-frequency magnetic field exposure level for Koreans by occupational code

This study attempted to identify the level of exposure of 350 subjects to the extremely low-frequency magnetic field(ELF-MF).The occupational group showed significantly high levels of ELF-MF in every exposure indicator during work and transportation(p<0.05).About 11%and 6%of the members of the occupational group were exposed to over 2mG and 4 mG,respectively,of ELF-MF during"all"activities.The 24-h ELF-MF exposure levels of the subjects in both groups were analyzed.In the occupational group,for every activity,the percentile for less than 2mG corresponded to 100%of C-4(agriculture),95%of C-1(professional),97%of C-2(engineer,office/sales),81%of C-3(services),85%of C-5(technician,labor management),and 50%of C-6(electrician).In the non-occupational group,the percentile for less than 2mG corresponded to 92%of students,83%of homemakers,81%of the elderly,and 88%of the unemployed.The percentile for over 4mG was 5%for students,homemakers,and the elderly and 13%of the unemployed.Electricians and the unemployed had the highest ELF-MF levels in both groups,respectively.Electricians were exposed to ELF-MF mostly at work,while the unemployed subjects were most affected by the activities classified under sleep and transportation.

Effects of ELF magnetic fields on protein expression profile of human breast cancer cell MCF7

Extremely Low Frequency Magnetic Fields (ELF MF) has been considered as a “possible human carcinogen” by International Agency for Research on Cancer (IARC) while credible mechanisms of its carcinogenicity remain unknown. In this study, a proteomics approach was employed to investigate the changes of protein expression profile induced by ELF MF in human breast cancer cell line MCF7, in order to determine ELF MF-responsive proteins. MCF7 cells were exposed to 50 Hz, 0.4 mT ELF MF for 24 h and the changes of protein profile were examined using two dimensional electrophoresis. Up to 6 spots have been statistically signifi-cantly altered (their expression levels were changed at least 5 fold up or down) compared with sham-exposed group. 19 ones were only detected in exposure group while 19 ones were missing. Three proteins were identified by LC-IT Tandem MS as RNA binding protein regulatory subunit、Proteasome subunit beta type 7 precursor and Translationally Controlled Tumor Protein. Our finding showed that 50 Hz, 0.4 mT ELF MF alternates the protein profile of MCF7 cell and may affect many physiological functions of normal cell and 2-DE coupled with MS is a promising ap-proach to elucidating cellular effects of electromagnetic fields.