Effect Of Extremely Low Frequency Magnetic Fields Research Articles

A Review of Aspects of Synaptic Plasticity in Hippocampus via mT Extremely Low-Frequency Magnetic Fields.

The subthreshold magnetic modulation technique stimulates cells with mT extremely low-frequency magnetic fields (ELF-MFs), which are insufficient to induce neuronal action potentials. Although they cannot directly induce resting neurons to discharge, mT magnetic stimulation can regulate the excitability of the nervous system, which regulates learning and memory by some unknown mechanisms. Herein, we describe the regulation of mT ELF-MFs with different parameters on synaptic plasticity in hippocampal neurons. Additionally, we summarize the latest research on the possible mechanism of the effect of ELF-MFs on synaptic plasticity. Some studies have shown that ELF-MFs are able to inhibit long-term potentiation (LTP) by increasing concentration of intracellular Ca2+ concentration ([Ca2+ ]i ), as well as concentration of reactive oxygen species. The research in this paper has significance for the comprehensive understanding of relevant neurological mechanisms of learning and memory by mT ELF-MFs stimulation. However, more high-quality research is necessary to determine the regulatory mechanism of mT ELF-MFs on synaptic plasticity in order to optimize this technique as a treatment for neurological diseases. © 2023 Bioelectromagnetics Society.

Effect of Short-time Exposure of Local Extremely Low-Frequency Magnetic Fields on Sleepiness in Male Rats.

Lack of high-quality sleep causes severe side effects like anxiety and changes in plasma concentration of oxalate. The current study investigated the impact of local extremely low-frequency magnetic fields (ELF-MFs) on inducing sleep (sleepiness) and anxiety in male rats. In this experimental study, 40 male rats were divided into four groups (n=10 for each group). The ELF-MF exposure (0, 10, and 18 Hz) was applied with an intensity of 200μT for three days (10 min/d). The sham-treated animal did not receive ELF-MF. Serum levels of oxalic acid (OA) and sleepiness were measured before and after the last exposure to ELF-MF or sham. Anxiety, sleepiness, and OA were measured using the elevated plus maze, open-field test (OFT), and ELISA test. A comparison of oxalate levels before and after exposure to ELF-MF revealed that ELF-MF (10 Hz) decreased the serum level of oxalate (P<0.05). Comparing open/closed arm entry (in an elevated plus maze) between before and after exposure to ELFMF revealed significant differences. Also, frequency, velocity, and distance moved were decreased in the open-field test. Results of the present study demonstrated that ELF-MF with short-time exposure may modulate the metabolism of OA and may modulate anxiety-like behavior or kind of induction of sleepiness in male rats. Oxalate acid concentration may reduce after short time ELF-MF exposure.Locomotor activity in male rats may decrease after the ELF-MF exposure.Short time ELF-MF exposure may induce sleepiness in male rats that may be used to treat sleep disorders. It is necessary for a person to have good sleep to feel happy during the day. The usual way to treat the patient's sleep disorders is drug therapy, but there are some non-pharmacological treatments such as cognitive behavioral therapy and proper diet. In this study we decided to evaluate the effect of ELF-MFs on sleep induction (sleepiness) in male rats by assessing behavioral tests and measuring oxalate acid density. The results showed that the activity of rats and oxalate acid concentration reduced after ELF-MF exposure. This was consistent with results of the plus maze test and the reduction of velocity, frequency and in the open-field test can be attributed to sleepiness. The results of this research showed that ELF-MF with short time exposure may modulate the anxiety-like behavior or kind of induction of sleepiness in male rats. This effect may be used to treat sleep disorders and requires further human studies.

Increases of bioethanol productivity by S. cerevisiae in unconventional bioreactor under ELF-magnetic field: New advances in the biophysical mechanism elucidation on yeasts

The aim of this work was to evaluate the bioethanol productivity in an unconventional bioreactor assisted by extremely low frequency (ELF) - electromagnetic field and elucidate the biophysical mechanism of action by which ELF magnetic fields improve the bioethanol production by S. cerevisiae. Fermentations were carried out under axial field lines at 10 mT magnetic flux density (B), using three different recycling arrangements (spiral-shape tube, u-shape tube and whole bioreactor) in a closed loop. Fermentation kinetics were monitored by cell growth, substrate consumption, ethanol and by-product formation. In addition, electrophysiological measurements of the H+ ion fluxes were carried out in yeast cells sampled at different fermentation stages. ELF magnetic fields increased the glucose uptake, bioethanol production and H+ efflux, shortening in 2 h the fermentation time. The greatest effects of the ELF magnetic fields were obtained in the whole bioreactor arrangement, reaching an average increase of 33% in the bioethanol production. The results are consistent with a stimulatory effect of ELF magnetic fields on the plasma membrane H+-ATPase activity, as indicated by the specific increase of the vanadate-sensitive component of the yeast cells H+ efflux, providing a new biophysical mechanism of action for the biological effect of magnetic fields.

EFFECTS OF EXTREMELY LOW-FREQUENCY MAGNETIC FIELD ON HEALTHY FIBROBLASTS AND BREAST CANCER CELLS

Objective: Modern people are exposed to many environmental factors, including Extremely Low-Frequency Magnetic Fields (ELF-MF). ELF-MFs are emitted from everything that produces electricity or that it passes through. Some studies have shown no significant detrimental effect of ELF-MFs on biological systems, while other studies have shown that ELF-MFs increase the risk of the development of childhood leukaemia (1). Moreover, the 40 Hz-7mT range ELF-MF has been used as a magnetotherapy instrument (2). In this study, we aimed to compare the effect of ELFMF on healthy dermal fibroblasts and breast cancer cells (MCF7). Material and Method: After the administration of 1 mT-50 Hz ELF-MF to healthy and cancer cells for different exposure times, apoptosis/necrosis levels were investigated and cell cycles and proliferation indexes were examined. The Analytic Hierarchy Process (AHP) was applied to find the most effective dose. Results: The ELF-MF did not show any significant effect on MCF7 cells. However, it caused increased apoptosis and decreased proliferation of healthy fibroblast cells. Furthermore, no changes in the cell cycle were observed in either cell line. As a result of AHP, the most effective exposure was determined to be 1 hour. Conclusion: Our results showed that while the ELF-MF reduces the viability of healthy fibroblasts, it has not observed therapeutic effect on breast cancer cells.&nbsp;

Insights in the biology of extremely low-frequency magnetic fields exposure on human health.

The extremely low-frequency magnetic fields (ELF-EMF) are generated by electrical devices and power systems (1 to 300Hz). In recent decades, exposure to ELF-EMF has emerged potential concerns on public health. Here, we discuss recent progress in the understanding of ELF-EMF biology with a focus on mechanisms of ELF-EMF-mediated disease and summarize the results of more recent experimental and epidemiological studies of ELF-EMF exposure effects on cancer, neurological, cardiovascular, and reproductive disorders. Current views on genomic instability effects, as well as scientific evidence about ELF-EMF therapy, are put forth. According to our literature review, exposure to ELF-EMF has an adverse biological effect depending on the current intensity, strength of the magnetic field, and duration of exposure. Accumulated epidemiologic evidence indicates a correlation between exposure to ELF-EMF and childhood cancer incidence, Alzheimer's disease (AD), and miscarriage. However, adult cancer does not show augmented risk caused by the ELF-EMF. Also, no consistent evidence exists in cardiovascular disease mortality due to ELF-EMF exposure. There is a lack of comprehensive mechanisms for explaining the biological effect of ELF-EMF. Eventually, more studies are needed to clarify the mechanisms of these magnetic fields.

Ataxia telangiectasia mutated deficiency does not result in genetic susceptibility to 50 Hz magnetic fields exposure in mouse embryonic fibroblasts.

Extremely low frequency magnetic field (ELF-MF) has been classified as a possible carcinogen to humans by the International Agency for Research on Cancer [2002]. However, debate on the genotoxic effects of ELF-MF has continued due to lack of sufficient experimental evidence. Ataxia telangiectasia mutated (ATM) plays a central role in DNA damage repair; its deficiency can result in cellular sensitivity to DNA-damaging agents. To evaluate the genotoxicity of ELF-MF, we investigated the effects of 50 Hz MF on DNA damage in ATM-proficient (Atm+/+ ) mouse embryonic fibroblasts (MEFs) and ATM-deficient (Atm-/- ) MEFs, a radiosensitive cell line. Results showed no significant difference in average number of γH2AX foci per cell (9.37 ± 0.44 vs. 9.08 ± 0.28, P = 0.58) or percentage of γH2AX foci positive cells (49.22 ± 1.86% vs. 49.74 ± 1.44%, P = 0.83) between sham and exposure groups when Atm+/+ MEFs were exposed to 50 Hz MF at 2.0 mT for 15 min. Extending exposure duration to 1 or 24 h did not significantly change γH2AX foci formation in Atm+/+ MEFs. Similarly, the exposure did not significantly affect γH2AX foci formation in Atm-/- MEFs. Furthermore, 50 Hz MF exposure also did not significantly influence DNA fragmentation, cell viability, or cell cycle progression in either cell types. In conclusion, exposure to 50 Hz MF did not induce significant DNA damage in either Atm+/+ or Atm-/- MEFs under the reported experimental conditions. Bioelectromagnetics. 39:476-484, 2018. © 2018 Wiley Periodicals, Inc.

The effect of local extremely low frequency magnetic field on student sleepiness

ObjectivesLack of high-quality sleep causes serious side effects. The current study aimed to investigate the impact of local extremely low frequency magnetic field (ELF-MF) on sleep and drowsiness in healthy young adults.MethodsSixty-five young adults (32 males and 31 females, aged 18–24, participated voluntarily in this randomized crossover clinical trial. 200 microTesla MF (3 minutes duration) at three frequencies (10, 14 and 18 Hz) was applied to the skull in areas C3, Cz and C4, respectively. The Stanford Sleepiness Scale (SSS) or Consciousness Test (CT), Epworth Sleepiness Scale (ESS) and Peabody Picture Vocabulary Test were used to evaluate drowsiness, sleepiness, and reaction time. These tests were done both before and after application of ELF-MF or sham operation.ResultsMinimum reaction time after exposure to ELF-MF increased compared to that before exposure (P = 0.03), while it was not significant for the sham group (P = 0.63). From the ESS questionnaire, the results indicated that there was no significant difference for males or females between the exposure and sham groups. The mean of the SSS scores was no different compared to that before exposure.ConclusionThe results of this study demonstrated that exposure to ELF-MF may influence reaction time in young healthy people. However, as the results of ESS and SSS were not different between exposure and non-exposure groups, further studies using larger sample sizes are recommended in order to reach better interpretations of the effects of ELF-MF on sleepiness in young people.

Exposure of Extremely-Low Frequency (ELF) magnetic field may cause human cancer

Introduction: Chronic exposure of non-ionizing extremely low-frequency magnetic fields (ELF-EMF) is considered as a health hazard due to its adverse effects on human body such as generation of any type of cancer. Stem cells are appropriate models to assess the effects of ELF-EMF on other cell lines and human beings. Materials and methods: Adipose tissue has been known as source of multi potent stromal human mesenchymal stem cells (MSCs) which can be obtained in less invasive method and in large amounts; so adipose-derived stem cells (ADSCs) were used in this study. Effect of ELF-EMF (intensities of 0.5 and 1 mT and 50 Hz) on proliferation rate of hADSCs was assessed in 20 and 40 min per day for 7 days. Trypan blue assay was performed to assess cell proliferation rate. Result: The results shown that 0.5 and 1 mT magnetic fields can promote the proliferation rate of adipose derived hMSCs according to the duration of exposure. Conclusion: These outcomes could approve the effect of ELF-EMF on cancer induction; although the effective mechanisms in this process are still unknown.

Extremely low frequency magnetic fields regulate differentiation of regulatory T cells: Potential role for ROS-mediated inhibition on AKT.

Our previous studies showed that extremely low frequency magnetic fields (ELF-MFs) inhibited tumor growth and change proportion of splenic regulatory T cells (Treg cells). Here, we focus on the effect of ELF-MFs on lung metastatic melanoma mouse model and the regulatory mechanism of ELF-MFs on the differentiation of Treg cells. Tumor-bearing mice were exposed to sham ELF-MFs and ELF-MFs (0.4 T, 7.5 Hz) 2 h/day for 27 days. Metastatic tumor burden of lung was significantly decreased after ELF-MF treatment. Compared to the control group, expressions of matrix metalloproteinase (MMP2, MMP9) and forkhead box P3 (Foxp3) in lung nodules significantly decreased in the ELF-MF group. Moreover, in vitro, after stimulated with anti-CD3, anti-CD28 antibodies and transforming growth factor-β (TGF-β) and treated with ELF-MFs for 2 h, expression of Foxp3 in total T cells was significantly decreased. Differentiation rate of Treg cells was inhibited from 32.0% to 22.1% by ELF-MFs. Furthermore, reactive oxygen species (ROS) was increased and phospho-serine/threonine protein kinase (p-AKT) was inhibited in both T cells and Jurkat cells. ROS scavenger N-acetyl-l-cysteine reversed inhibition of AKT pathway and expression of Foxp3 from 18.6% to 26.6% in T cells. Taken together, our data show that ELF-MF exposure promoted the inhibitory effect of ROS on AKT pathway and decreased Foxp3 expression, which provides an explanation for why ELF-MF exposure can inhibit differentiation of Treg cells and enhance antitumor effect in metastatic melanoma mouse model.

Effect of extremely low frequency magnetic fields on cell proliferation and gene expression

Owing to concerns regarding possible effects of extremely low frequency magnetic fields (ELF-MF) on human health, many studies have been conducted to elucidate whether ELF-MF can induce modifications in biological processes. Despite this, controversies regarding effects of ELF-MF are still rife. In this study, we investigated biological effects of ELF-MF on MCF10A, MCF7, Jurkat, and NIH3T3 cell lines. ELF-MF with a magnetic flux density of 1 mT at 60 Hz was employed to stimulate cells for 4 or 16 h, after which the effects of ELF-MF on cell proliferation, cell death, cell viability, and DNA synthesis rates were assessed. Whereas Jurkat and NIH3T3 cells showed no consistent variation in cell number, cell viability, and DNA synthesis rate, MCF10A and MCF7 cells showed consistent and significant decreases in cell number, cell viability, and DNA synthesis rates. However, there was no effect of ELF-MF on cell death in any of tested cell lines. Next, to investigate the effect of ELF-MF on gene expression, we exposed MCF7 cells to 2 mT at 60 Hz for 16 h and examined transcriptional responses by using gene expression array. We found a gene, PMAIP1, that exhibited statistically significant variation using two-fold cut-off criteria and certified its expression change by using semi-quantitative and quantitative reverse transcription polymerase chain reaction. From these results, we concluded that ELF-MF could induce the delay of cell cycle progression in MCF7 and MCF10A cells in a cell context-specific manner and could up-regulate PMAIP1 in MCF7 cells.

Effects of 60-Hz Magnetic Fields on DNA Damage Responses in HT22 Mouse Hippocampal Cell Lines

Previously, we investigated extremely low-frequency magnetic fields (ELF-MFs) on diverse DNA damage responses, such as phosphorylated H2AX (<TEX>${\gamma}H2AX$</TEX>), comet tail moments, and aneuploidy production in several non-tumorigenic epithelial or fibroblast cell lines. However, the effect of ELF-MF on DNA damage responses in neuronal cells may not be well evaluated. Here, we investigated the effects of ELF-MF on the DNA damage responses in HT22 non-tumorigenic mouse neuronal cells. Exposure to a 60-Hz, 2 mT ELF-MF did not produce any increased <TEX>${\gamma}H2AX$</TEX> expression, comet tail moments, or aneuploidy formation. However, 2 mT ELF-MF transiently increased the cell number. From the results, ELF-MF could affect the DNA damage responses differently, depending on the cell lines.

Extremely low frequency magnetic fields inhibit adipogenesis of human mesenchymal stem cells.

It was reported that obese (Ob/Ob) mice lose their weight and fat when treated with 0.5 T direct current electromagnetic fields. We also observed that 7.5 Hz, 0.4 T rotation of extremely low frequency magnetic fields (ELF-MF) has an inhibitory effect on obesity. Mesenchymal stem cells (MSCs) are multi-potent cells capable of differentiating to different MSC lineages, including adipose. We hypothesized that inhibitory effects of ELF-MF on obesity may be related to the differentiation of MSCs to adipocytes. In the present study, we investigated the effects of 7.5 Hz, 0.4 T ELF-MF on differentiation of human umbilical cord MSCs. We found that ELF-MF inhibited adipogenic differentiation (exposed 2 h/day for 15 days) of MSCs but had no effect on osteogenic differentiation (exposed 2 h/day for 21 days). Moreover, ELF-MF inhibited adipocyte-specific expression of peroxisome proliferator-activated receptor 2 (PPARγ2). ELF-MF promoted c-Jun N-terminal kinase (JNK)-dependent intracellular signaling in MSCs. Furthermore, activation of the non-canonical Wnt pathway provoked the inhibition of PPARγ2 expression resulting in suppression of adipogenic differentiation. In addition, the effects of ELF-MF on growth and apoptosis of MSCs were not observed. Our data indicated that ELF-MF of 7.5 Hz, 0.4 T inhibited the adipogenic differentiation of MSCs via JNK-dependent Wnt signaling pathway, but had no effect on the growth and function of MSCs, suggesting the inhibitory effect of ELF-MF on obesity may be attributed to the inhibition of differentiation of MSCs into adipocytes. This study may provide a potential approach for the treatment of obesity.

Extremely low-frequency magnetic field exposure, electrical shocks and risk of Parkinson's disease.

Previous studies did not provide strong evidence for an increased Parkinson's disease (PD) risk after exposure to extremely low-frequency magnetic fields (ELF-MF), but were limited in their scope to address other exposures related to the use of electricity such as electrical shocks. We evaluated the associations of PD with exposure to ELF-MF, electrical shocks and having worked in "electrical occupations." We conducted a hospital-based case-control study, including 444 PD patients and 876 age- and sex-matched controls. Occupational histories were collected in telephone interviews and were linked to job-exposure matrices on ELF-MF exposure and on electrical shocks. In addition, questions on use of household appliances involving ELF-MF exposure, experienced electrical shocks and potential confounders were asked. No association of PD risk with any of the evaluated exposures related to electricity was observed. We did, however, observe quite consistently reduced risk estimates across the majority of the exposure categories explored. Given the results of the previous studies and the absence of any postulated mechanism, this is unlikely to represent a true protective effect of ELF-MF or electrical shocks on the occurrence of PD. The results of this study suggest that no association exists between PD and exposure to ELF-MF, electrical shocks or having worked in "electrical occupations."

Effects of extremely low frequency alternating-current magnetic fields on the growth performance and digestive enzyme activity of tilapia Oreochromis niloticus

Extremely low frequency magnetic field (ELF-MF), as a ubiquitous ecophysiological factor, has been determined to influence the health of human and animals worldwide. In this study, we focused on the effects of ELF-MF on growth performance and digestive enzyme activity in juvenile tilapia, Oreochromis niloticus. Totally 450 fish were exposed to ELF-MF (50 Hz; 0, 30, 100, 150 and 200 μT) for 30 days, respectively. The effects on growth and digestion were monitored on the 10th, 20th, and 30th day after induction (immediate effect), as well as 20th day after cessation of exposure (delayed effect). The activities of pepsin and intestinal protease of tilapia were significantly decreased after exposure in certain intensities of ELF-MF, but recovered when the ELF-MF exposure was removed 20 days later. Similar effects were also observed in the growth parameters, moreover interestingly, the specific growth rate (SGR) even represented a compensatory growth. To our knowledge, the present research provides the first determination that a certain extent of ELF-MF exposure could inhibit the growth and digestion of fish, and cause compensatory restorations after being removed upon a time.

Extremely Low-Frequency Magnetic Exposure Appears to Have No Effect on Pathogenesis of Alzheimer’s Disease in Aluminum-Overloaded Rat

ObjectiveExtremely low-frequency magnetic field (ELF-MF) has been reported to be of potential pathogenetic relevance to Alzheimer's disease (AD) for years. However, evidence confirming this function remains inconclusive. Chronic Al treatment has been identified as a contributing factor to cognitive function impairment in AD. This study aims to examine whether or not ELF-MF and Al have synergistic effects toward AD pathogenesis by investigating the effects of ELF-MF with or without chronic Al treatment on SD rats.MethodsSprague-Dawley (SD) rats were subjected one of the following treatments: sham (control group), oral Al (Al group), ELF-MF (100 µT at 50 Hz) with oral Al (MF+Al group), or ELF-MF (100 µT at 50 Hz) without oral Al (MF group).ResultsAfter 12 wk of treatment, oral Al treatment groups (Al and MF+Al groups) showed learning and memory impairment as well as morphological hallmarks, including neuronal cell loss and high density of amyloid-β (Aβ) in the hippocampus and cerebral cortex. ELF-MF without Al treatment showed no significant effect on AD pathogenesis. ELF-MF+Al treatment induced no more damage than Al treatment did.ConclusionsOur results showed no evidence of any association between ELF-MF exposure (100 µT at 50 Hz) and AD, and ELF-MF exposure does not influence the pathogenesis of AD induced by Al overload.

Effects of ELF Magnetic Field in Combination with Iron(III) Chloride (FeCl3) on Cellular Growth and Surface Morphology of Escherichia coli (E. coli)

This study investigated the effects of extremely low frequency (ELF) magnetic field with/without iron(III) chloride (FeCl3) on bacterial growth and morphology. The ELF exposures were carried out using a pair of Helmholtz coil-based ELF exposure system which was designed to generate 50Hz sinusoidal magnetic field. The field was approximately uniform throughout the axis of the coil pair. The samples which were treated or non-treated with different concentrations FeCl3 were exposed to 50Hz, 2millitesla (mT) magnetic field for 24h. ELF effect on viability was assessed in terms of viable colony counts (in colony-forming unit per milliliter) with the standard plate count technique. Scanning electron microscopy was used to investigate the magnetic field effect on surface morphology of Escherichia coli. No significant results were seen in terms of cell viability between ELF and sham-exposed bacterial strains. Similarly, FeCl3 treatment did not change cell viability of E. coli samples. However, we observed some morphological changes on E. coli cell surfaces. Pore formations and membrane destruction were seen on the surface of 24h ELF field-exposed cells. We concluded that ELF magnetic field exposure at 2mT does not affect cell viability; however, it may affect bacterial surface morphology.

Do 100- and 500-μT ELF magnetic fields alter beta-amyloid protein, protein carbonyl and malondialdehyde in rat brains?

Several studies still state that presently accepted safety standards for extremely low-frequency magnetic fields (ELF-MFs) do not provide adequate protection, and therefore the standards are still open to question. To help resolve this question, the aim of this study was to illuminate the interaction between biomolecules and ELF-MFs by investigating the effect of ELF-MFs on beta-amyloid protein (BAP), protein carbonyl (PC) and malondialdehyde (MDA) in rat brain. For this study, 30 adult male Sprague-Dawley rats were used, which were divided into two experimental groups and a sham exposed group. Rats in two experimental groups were exposed to 100- and 500-μT ELF-MFs (50 Hz) for 2 h/day for 10 months, which are the generally accepted safety standards for public and occupational exposures. The same procedures were applied to the rats in the sham group, but with the generator turned off. The results of this study showed that neither ELF-MFs used in this study altered BAP level significantly (p>0.05). However, PC and MDA levels were increased by the exposure to 100- and 500-μT ELF-MFs (p < 0.0001). In conclusion, both PC and MDA levels were altered by long-term exposure to either 100 or 500 μT ELF-MF. However, many further and more comprehensive studies will be required to elucidate the interaction mechanisms between ELF-MFs exposure and living organisms.

The effects of extremely low-frequency magnetic fields on melatonin and cortisol, two marker rhythms of the circadian system

In the past 30 years the concern that daily exposure to extremely low-frequency magnetic fields (ELF-EMF) (1 to 300 Hz) might be harmful to human health (cancer, neurobehavioral disturbances, etc) has been the object of debate, and has become a public health concern. This has resulted in the classification of ELF-EMF into category 2B, ie, agents that are "possibly carcinogenic to humans" by the International Agency for Research on Cancer. Since melatonin, a neurohormone secreted by the pineal gland, has been shown to possess oncostatic properties, a "melatonin hypothesis" has been raised, stating that exposure to EMF might decrease melatonin production and therefore might promote the development of breast cancer in humans. Data from the literature reviewed here are contradictory. In addition, we have demonstrated a lack of effect of ELF-EMF on melatonin secretion in humans exposed to EMF (up to 20 years' exposure) which rebuts the melatonin hypothesis. Currently, the debate concerns the effects of ELF-EMF on the risk of childhood leukemia in children chronically exposed to more than 0.4 μT. Further research is thus needed to obtain more definite answers regarding the potential deleterious effects of ELF-EMF.

Molecular basis underlying the biological effects elicited by extremely low-frequency magnetic field (ELF-MF) on neuroblastoma cells

Extremely low-frequency magnetic fields (ELF-MFs) may affect human health because of the possible associations with leukemia but also with cancer, cardiovascular, and neurological disorders. In the present work, human SH-SY5Y neuroblastoma cells were exposed to a 50 Hz, 1 mT sinusoidal ELF-MF at three different times, that is, 5 days (T5), 10 days (T10), and 15 days (T15) and then the effects of ELF-MF on proteome expression and biological behavior were investigated. Through comparative analysis between treated and control samples, we analyzed the proteome changes induced by ELF-MF exposure. Nine new proteins resolved in sample after a 15-day treatment were involved in a cellular defense mechanism and/or in cellular organization and proliferation such as peroxiredoxin isoenzymes (2, 3, and 6), 3-mercaptopyruvate sulfurtransferase, actin cytoplasmatic 2, t-complex protein subunit beta, ropporin-1A, and profilin-2 and spindlin-1. Our results indicated that ELF-MFs exposure altered the proliferative status and other important cell biology-related parameters, such as cell growth pattern, and cytoskeletal organization. These findings support our hypothesis that ELF radiation could trigger a shift toward a more invasive phenotype.

Toxicity and SOS-response to ELF magnetic fields and nalidixic acid in E. coli cells

Extremely low-frequency magnetic fields (ELF-MF) have previously been shown to affect conformation of chromatin and cell proliferation. Possible genotoxic and carcinogenic effects of ELF-MF have also been discussed and tested. In this study, we analysed the effect of ELF-MF on chromatin conformation in E. coli GE499 cells by the anomalous viscosity time-dependence (AVTD) technique. Possible genotoxic effects of the specific combination of static and ELF-MF, which has been proven to affect chromatin conformation, were investigated by a clonogenic assay, by assessing cell-growth kinetics, and by analysis of the SOS-response by means of inducible recA-lacZ fusion-gene products and the β-galactosidase assay. The genotoxic agent nalidixic acid (NAL) was used as a positive control and in combination with ELF-MF. Nalidixic acid at 3–30μg/ml decreased the AVTD peaks and induced a cytotoxic effect. In contrast to NAL, ELF-MF fields increased AVTD, stimulated cell growth, and increased cloning efficiency. These effects depended on the frequency within the range of 7–11Hz. While NAL induced an SOS-response, exposure to ELF-MF did not induce the recA-lacZ fusion-gene product. Exposure to ELF-MF did not modify the genotoxic effects of NAL either. All together, the data show that ELF-MF, under specific conditions of exposure, acted as a non-toxic but cell-growth stimulating agent.