Analgesic effect of the electromagnetic resonant frequencies derived from the NMR spectrum of morphine

Exposure to various types of electromagnetic fields (EMFs) affects pain specificity (nociception) and pain inhibition (analgesia). Previous study of ours has shown that exposure to the resonant spectra derived from biologically active substances' NMR may induce to live targets the same effects as the substances themselves. The purpose of this study is to investigate the potential analgesic effect of the resonant EMFs derived from the NMR spectrum of morphine. Twenty five Wistar rats were divided into five groups: control group; intraperitoneal administration of morphine 10 mg/kg body wt; exposure of rats to resonant EMFs of morphine; exposure of rats to randomly selected non resonant EMFs; and intraperitoneal administration of naloxone and simultaneous exposure of rats to the resonant EMFs of morphine. Tail Flick and Hot Plate tests were performed for estimation of the latency time. Results showed that rats exposed to NMR spectrum of morphine induced a significant increase in latency time at time points (p < 0.05), while exposure to the non resonant random EMFs exerted no effects. Additionally, naloxone administration inhibited the analgesic effects of the NMR spectrum of morphine. Our results indicate that exposure of rats to the resonant EMFs derived from the NMR spectrum of morphine may exert on animals similar analgesic effects to morphine itself.     

Effects of mobile phone radiofrequency on the structure and function of the normal human hemoglobin

Widespread use of mobile phones has increased the human exposure to electromagnetic fields (EMFs). It is required to investigate the effect of EMFs on the biological systems. In this paper the effect of mobile phone RF (910 MHz and 940 MHz) on structure and function of HbA was investigated. Oxygen affinity was measured by sodium dithionite with UV–vis spectrophotometer. Structural changes were studied by circular dichroism and fluorescence spectroscopy. The results indicated that mobile phone EMFs altered oxygen affinity and tertiary structure of HbA. Furthermore, the decrease of oxygen affinity of HbA corresponded to the EMFs intensity and time of exposure.     

Assessing of plasma protein denaturation induced by exposure to cadmium,electromagnetic fields and their combined actions on rat

In our environment, we have numerous chances to be exposed to not only electromagnetic fields (EMFs) but also many chemicals containing mutagens. Therefore, the aim of this study was to estimate whether rat’s exposure to cadmium and/or EMFs could cause oxidative damage to molecular structure of proteins and whether and to what extent the effects of co-exposure differ from those observed under the treatment with each exposure alone. Thirty-two rats were divided into four groups. Group 1 was termed as control, group 2 was treated with cadmium (3.0?mg/Kg), group 3 was exposed to EMF (10?mT/h/day) and group 4 was treated with cadmium and exposed to EMF. Protein carbonyls (PCO) in the plasma as a marker of oxidative protein damage and total oxidant status (TOS), as well as electrical conductivity and SDS electrophoresis to estimate changes in molecular structure of protein, were determined. The exposure to Cd and/or EMF led to oxidative protein damage (increased PCO and TOS) accomplished by increased stress of electrical charges on the surface of the protein molecule (increased electrical conductivity) and changes in the molecular structure of protein. The effects were more pronounced after treatment with both Cd and EMF than at the treatment with each exposure alone. The serious damage to proteins at the co-exposure to Cd and EMF seems to be due to the interference of the EMF with the toxic activity of cadmium. This work concluded that combined exposure to Cd and EMFs might increase the risk of plasma damage via enhancing free radical generation and protein oxidation.     

Effect of intermittent and continuous exposure to electromagnetic fields on cultured hippocampal cells

This study was designed to assess the effect of 50 Hz electromagnetic fields (EMFs) on hippocampal cell cultures in the presence or absence of either sodium nitroprusside (SNP, a NO donor) or Fe2+ induced oxidative stress. One week old cultured rat hippocampal cells were exposed to either intermittent EMFs (IEMFs, 50 Hz, 0-5 mT, 1 min ON/OFF cycles, repeated 10 times every 2 h, 6 times/day during 48 h) or continuous EMFs (CEMFs, 50 Hz, 0-5 mT for 48 h). In a second set of experiments, the effect on such EMFs applied in combination with oxidative stress induced by 0.5 microM Fe2+ or SNP was estimated. At the end of both sets of experiments, cell mortality was assessed by lactate dehydrogenase measurements (LDH). Neither type of exposure to EMFs was observed to modify the basal rate of cell mortality. The exposure to CEMFs in presence of either NO or Fe2+ did not induce any significant increase in cell death. However, when cells were exposed to EMFs in the presence of NO, we observed a significant increase in cell death of 11 and 23% (P<0.001) at 2.5 and 5 mT, respectively. This effect had some specificity because IEMFs did not modify the effect of Fe2+ on cell mortality. Although the effects of IEMFs reported in this study were only observed at very high intensities, our model may prove valuable in trying to identify one cellular target of EMFs.     

Exposure to 900 MHz electromagnetic field induces an unbalance between pro-apoptotic and pro-survival signals in T-lymphoblastoid leukemia CCRF-CEM cells

It has been recently established that low-frequency electromagnetic field (EMFs) exposure induces biological changes and could be associated with increased incidence of cancer, while the issue remains unresolved as to whether high-frequency EMFs can have hazardous effect on health. Epidemiological studies on association between childhood cancers, particularly leukemia and brain cancer, and exposure to low- and high-frequency EMF suggested an etiological role of EMFs in inducing adverse health effects. To investigate whether exposure to high-frequency EMFs could affect in vitro cell survival, we cultured acute T-lymphoblastoid leukemia cells (CCRF-CEM) in the presence of unmodulated 900 MHz EMF, generated by a transverse electromagnetic (TEM) cell, at various exposure times. We evaluated the effects of high-frequency EMF on cell growth rate and apoptosis induction, by cell viability (MTT) test, FACS analysis and DNA ladder, and we investigated pro-apoptotic and pro-survival signaling pathways possibly involved as a function of exposure time by Western blot analysis. At short exposure times (2-12 h), unmodulated 900 MHz EMF induced DNA breaks and early activation of both p53-dependent and -independent apoptotic pathways while longer continuous exposure (24-48 h) determined silencing of pro-apoptotic signals and activation of genes involved in both intracellular (Bcl-2) and extracellular (Ras and Akt1) pro-survival signaling. Overall our results indicate that exposure to 900 MHz continuous wave, after inducing an early self-defense response triggered by DNA damage, could confer to the survivor CCRF-CEM cells a further advantage to survive and proliferate.     

Nonthermal electromagnetic fields and estimation of the probable development of the convulsive syndrome

Development of the convulsive syndrome occurs during exposure to electromagnetic fields (EMFs) during physiotherapy and under conditions of professional work. Some researchers believe that EMFs may have medical effects during the treatment of the epilepsy syndrome. Some publications have noted the development of epileptic convulsions in experiments using EMF exposures at various frequencies. Four conditions that may promote the development of convulsions upon EMF exposure are considered.     

Extremely low-frequency electromagnetic fields do not affect DNA damage and gene expression profiles of yeast and human lymphocytes

We studied the effects of extremely low-frequency (50 Hz) electromagnetic fields (EMFs) on peripheral human blood lymphocytes and DBY747 Saccharomyces cerevisiae. Graded exposure to 50 Hz magnetic flux density was obtained with a Helmholtz coil system set at 1, 10 or 100 microT for 18 h. The effects of EMFs on DNA damage were studied with the single-cell gel electrophoresis assay (comet assay) in lymphocytes. Gene expression profiles of EMF-exposed human and yeast cells were evaluated with DNA microarrays containing 13,971 and 6,212 oligonucleotides, respectively. After exposure to the EMF, we did not observe an increase in the amount of strand breaks or oxidated DNA bases relative to controls or a variation in gene expression profiles. The results suggest that extremely low-frequency EMFs do not induce DNA damage or affect gene expression in these two different eukaryotic cell systems.     

Neural stimulation on human bone marrow‐derived mesenchymal stem cells by extremely low frequency electromagnetic fields

Adult stem cells are considered multipotent. Especially, human bone marrow‐derived mesenchymal stem cells (hBM‐MSCs) have the potential to differentiate into nerve type cells. Electromagnetic fields (EMFs) are widely distributed in the environment, and recently there have been many reports on the biological effects of EMFs. hBM‐MSCs are weak and sensitive pluripotent stem cells, therefore extremely low frequency‐electromagnetic fields (ELF‐EMFs) could be affect the changes of biological functions within the cells. In our experiments, ELF‐EMFs inhibited the growth of hBM‐MSCs in 12 days exposure. Their gene level was changed and expression of the neural stem cell marker like nestin was decreased but the neural cell markers like MAP2, NEUROD1, NF‐L, and Tau were induced. In immunofluorescence study, we confirmed the expression of each protein of neural cells. And also both oligodendrocyte and astrocyte related proteins like O4 and GFAP were expressed by ELF‐EMFs. We suggest that EMFs can induce neural differentiation in BM‐MSCs without any chemicals or differentiation factors. © 2012 American Institute of Chemical Engineers Biotechnol. Prog., 2012     

The effects of low-frequency environmental-strength electromagnetic fields on brain electrical activity: a critical review of the literature

Reports dealing with the stimulus-response relationship between low-level, low-frequency electromagnetic fields (EMFs) and changes in brain electrical activity permit assessment of the hypothesis that EMFs are detected by the body via the process of sensory transduction. These reports, as well as those involving effects on brain activity observed after a fixed time of exposure, are critically reviewed here. A consistent stimulus-response relationship between EMFs and changes in brain activity has been demonstrated in animal and human subjects. The effects, which consisted of onset and offset evoked potentials, were observed under conditions permitting the inference that the fields were transduced like ordinary stimuli such as light and sound. However, unlike the changes in brain activity induced by these stimuli, the changes induced by EMFs were governed by nonlinear laws. The studies involving attempts to determine whether a period of EMF exposure caused a metabolic effect reflected in pre-exposure/post-exposure differences in brain activity were generally inconclusive.     

Tempol suppresses micronuclei formation in astrocytes of newborn rats exposed to 50-Hz, 10-mT electromagnetic fields under bleomycin administration

A number of epidemiological studies have suggested that exposure to environmental and occupational electromagnetic fields (EMFs) contribute to the induction of brain tumors. The aim of this study was to investigate the mutagenetic effects of co-exposure to 50-Hz, 10-mT EMFs and bleomycin (BLM) using an ex vivo newborn rat astrocyte micronucleus assay. We also investigated whether the mutagenetic effects of EMFs were related to active oxygen species by using 4-hydroxy-2,2,6,6-tetramethyl piperidine-1-oxyl (tempol), a superoxide radical scavenger. Three-day-old male Sprague-Dawley rats were co-exposed to 50-Hz EMFs and BLM (5 or 10mg/kg body weight (BW)) in each group (n=6; total 6 group), and were co-exposed to 50-Hz EMFs and 10mg/kg BW BLM with administration of 200μmol/kg BW tempol in each group (total 4 group). Brain cells were dissociated into single cells, cultured for 96h, incubated with an antibody against glial fibrillary acidic protein, and stained with acridine orange. The frequency of micronucleated astrocytes was determined using a fluorescence microscope. The frequency of micronucleated astrocytes in the 10mg/kg BW bleomycin plus EMF exposure group (Mean±SD: 19.8±5.2‰) was 1.6 times higher than that in the 10mg/kg BW bleomycin plus sham-exposure group (Mean±SD: 12.7±3.3‰) (p<0.05). Analysis of the frequency of micronuclei in astrocytes after co-exposure to EMF and bleomycin for 72h and administration of tempol revealed that, in the EMF exposure group, the frequency of micronuclei in rats administered with 10mg/kg BW bleomycin and treated with tempol (Mean±SD: 11.2±1.9‰) was 40% of that in rats administered with the same dose of bleomycin and physiological saline (Mean±SD: 28.0±15.0‰) (p<0.01). Results of the current study suggested that the mechanism responsible for the elevated frequency of micronuclei in astrocytes of rats co-exposed to BLM and EMFs is related to active oxygen species.     

Biological effects of continuous exposure of embryos and young chickens to electromagnetic fields emitted by video display units

The effects of continuous exposure of embryos and young chickens to electromagnetic fields (EMFs) emitted by video display units (VDUs) were investigated. Embryos and brood were continuously exposed during embryonic and postembryonic phases to EMFs emitted by two types of VDU (TV or computer). Embryonic mortality was evaluated in three independent experiments. Young chickens were immunized three times by porcine thyroglobulin (Tg). Blood samples were assayed after each immunization for specific anti-Tg antibodies (IgG), plasma corticosterone (CORT), and plasma melatonin (MLT). In the sham-exposed samples, embryonic death (10–33%) was restricted to the perinatal period and the IgG, CORT, and MLT responses of young chickens crested after the second immunization. Constant EMF exposure was accompanied by significantly increased fetal loss (47–68%) and markedly depressed levels of circulating anti-Tg IgG, CORT, and MLT. Collectively, these findings indicate that continuous exposure to EMFs, issuing from VDUs, adversely affects embryos and young chickens. Bioelectromagnetics 18:514–523, 1997. © 1997 Wiley-Liss, Inc.     

The effect of pulsed electromagnetic fields on the physiologic behaviour of a human astrocytoma cell line

We evaluated the effects of 50 Hz pulsed electromagnetic fields (EMFs) with a peak magnetic field of 3 mT on human astrocytoma cells. Our results clearly demonstrate that, after the cells were exposed to EMFs for 24 h, the basal [Ca(2+)](i) levels increased significantly from 124+/-51 nM to 200+/-79 nM. Pretreatment of the cells with 1.2 microM substance P increased the [Ca(2+)](i) to 555+/-278 nM, while EMF exposure caused a significant drop in [Ca(2+)](i) to 327+/-146 nM. The overall effect of EMFs probably depends on the prevailing Ca(2+) conditions of the cells. After exposure, the proliferative responses of both normal and substance P-pretreated cells increased slightly from 1.03 to 1.07 and 1.04 to 1.06, respectively. U-373 MG cells spontaneously released about 10 pg/ml of interleukin-6 which was significantly increased after the addition of substance P. Moreover, immediately after EMF exposure and 24 h thereafter, the interleukin-6 levels were more elevated (about 40%) than in controls. On the whole, our data suggest that, by changing the properties of cell membranes, EMFs can influence Ca(2+) transport processes and hence Ca(2+) homeostasis. The increased levels of interleukin-6 after 24 h of EMF exposure may confirm the complex connection between Ca(2+) levels, substance P and the cytokine network.     

50Hz 1．8mT电磁场对成骨细胞增殖与分化成熟影响的波形比较研究

在50 Hz 1.8 mT的4种不同波形电磁场(electromagnetic fields,EMFs)中筛选促进体外培养大鼠成骨细胞(rat osteoblasts,ROB)增殖与分化成熟的最佳波形.体外分离培养大鼠颅骨成骨细胞,传代后随机分为5组,分别用频率50 Hz,EMFs强度为0 mT(对照组)和1.8 mT的正弦波、三角波、方波和锯齿波处理ROB,30 min/(次.天).在磁场处理后4～8天细胞呈现特征样分布.方波促进成骨细胞增殖,正弦波抑制成骨细胞增殖.三角波和正弦波增加ALP活性,其中ALP染色、茜素红钙化结节染色和胶原Ⅰ(collagen-Ⅰ)免疫组织化学检测结果与ALP活性一致.在EMFs处理后的24 h、96 h和72 h后EMFs分别提高Runx-2、Opg和Igf基因表达水平,其中尤以正弦波和三角波作用最为显著.上述结果表明:50 Hz 1.8 mT方波促进成骨细胞增殖,正弦波抑制成骨细胞增殖.50 Hz 1.8 mT EMFs能促进体外培养成骨细胞分化成熟,其中尤以正弦波和三角波促进成骨细胞分化成熟作用最为显著.     

Induction of Autophagy in the Striatum and Hypothalamus of Mice after 835 MHz Radiofrequency Exposure

The extensive use of wireless mobile phones and associated communication devices has led to increasing public concern about potential biological health-related effects of the exposure to electromagnetic fields (EMFs). EMFs emitted by a mobile phone have been suggested to influence neuronal functions in the brain and affect behavior. However, the affects and phenotype of EMFs exposure are unclear. We applied radiofrequency (RF) of 835 MHz at a specific absorption rate (SAR) of 4.0 W/kg for 5 hours/day for 4 and 12 weeks to clarify the biological effects on mouse brain. Interestingly, microarray data indicated that a variety of autophagic related genes showed fold-change within small range after 835 MHz RF exposure. qRT-PCR revealed significant up-regulation of the autophagic genes Atg5, LC3A and LC3B in the striatum and hypothalamus after a 12-week RF. In parallel, protein expression of LC3B-II was also increased in both brain regions. Autophagosomes were observed in the striatum and hypothalamus of RF-exposed mice, based on neuronal transmission electron microscopy. Taken together, the results indicate that RF exposure of the brain can induce autophagy in neuronal tissues, providing insight into the protective mechanism or adaptation to RF stress.     

Low-Frequency Electromagnetic Fields Alter the Replication Cycle of MS2 Bacteriophage

The effect of exposure to 60-Hz electromagnetic fields (EMFs) on RNA coliphage MS2 replication was studied. EMF exposure commenced when the bacterial cultures were inoculated with the phage (t = 0). In 12 experiments in which the strength of the field was 5 G, a significant delay in phage yield was found in the EMF-exposed cultures 45–65 min after inoculation, compared with control cultures. However, the EMF did not alter the final phage concentration. Experiments at 25 G (N = 5) suggested that the stronger field resulted in both impeded phage replication and increased phage yield. No differences between test groups were found in experiments involving sham-EMF exposure, thereby indicating that the results obtained with the EMFs were not due to systematic error. It appears that MS2, which codes for only four proteins, is the simplest biological system in which an EMF-induced effect has been demonstrated. The MS2 system is, therefore, conducive to follow-up studies aimed at understanding the level and nature of the underlying interaction process, and perhaps to biophysical modeling of the interaction process. Received: 26 August 1997 / Accepted: 17 November 1997     

Exposure to 900 MHz electromagnetic field induces an unbalance between pro‐apoptotic and pro‐survival signals in T‐lymphoblastoid leukemia CCRF‐CEM cells

The original article to which this Erratum was published in J. Cell. Physiol. 198:324–332, 2004 It has been recently established that low‐frequency electromagnetic field (EMFs) exposure induces biological changes and could be associated with increased incidence of cancer, while the issue remains unresolved as to whether high‐frequency EMFs can have hazardous effect on health. Epidemiological studies on association between childhood cancers, particularly leukemia and brain cancer, and exposure to low‐ and high‐frequency EMF suggested an etiological role of EMFs in inducing adverse health effects. To investigate whether exposure to high‐frequency EMFs could affect in vitro cell survival, we cultured acute T‐lymphoblastoid leukemia cells (CCRF‐CEM) in the presence of unmodulated 900 MHz EMF, generated by a transverse electromagnetic (TEM) cell, at various exposure times. We evaluated the effects of high‐frequency EMF on cell growth rate and apoptosis induction, by cell viability (MTT) test, FACS analysis and DNA ladder, and we investigated pro‐apoptotic and pro‐survival signaling pathways possibly involved as a function of exposure time by Western blot analysis. At short exposure times (2–12 h), unmodulated 900 MHz EMF induced DNA breaks and early activation of both p53‐dependent and ‐independent apoptotic pathways while longer continuous exposure (24–48 h) determined silencing of pro‐apoptotic signals and activation of genes involved in both intracellular (Bcl‐2) and extracellular (Ras and Akt1) pro‐survival signaling. Overall our results indicate that exposure to 900 MHz continuous wave, after inducing an early self‐defense response triggered by DNA damage, could confer to the survivor CCRF‐CEM cells a further advantage to survive and proliferate. J. Cell. Physiol. 198: 324–332, 2004. © 2003 Wiley‐Liss, Inc.     

Effects of Electromagnetic Fields on the Bioactivities of an Osteoblast-Like Cell Line (UMR-106)

In the present study, we first investigated the effects of various types of low-energy, low-frequency electromagnetic fields (EMFs) on DNA synthesis in UMR-106 osteoblast-like cells. The experimental groups were exposed to EMFs for 2 days (twice/day, 30 min/time), and DNA synthesis was measured. The results showed that the cells responded most sensitively to EMFs of some specific combinations of the parameters by an increase in DNA synthesis, implying that EMFs with a specific waveform rather than a complex one can be used in clinical electrotherapy. The parameters were as follows: pulsed electric field (PEF) with pulse width 0.2 ms, field strength 10 V/cm, frequency 125 Hz; sinusoidal electric field (SEF) with field strength 1 V/cm, frequency 10 Hz; and alternating magnetic field (AMF) with field density 0.5 mT, frequency 5 Hz. In addition to frequency, the field strength or field density within a suitable intensity scale played a dominant role in causing the DNA synthesis response. We then compared the effects of two kinds of fields, PEF and AMF, with the optimum parameters identified by the experiments, on alkaline phosphatase (ALP) activity, protein and collagen synthesis, and intracellular levels of cyclic adenosine monophosphate (cAMP). The results indicated that both fields could not only affect UMR-106 cells proliferation but could particularly affect a series of characteristic bioactivities of UMR-106 such as ALP activity and collagen synthesis. The intracellular cAMP levels were increased rapidly and greatly with exposure to both PEF and AMF, implying that the action of low-frequency EMFs proceeds via second messenger-dependent processes originating from signals at the cell membrane. The difference in action between PEF and AMF suggests that they may couple to the cell membrane in a partially different way.     

Effects of GSM cellular phones on human hearing: the European project "GUARD"

The European multicenter project named GUARD involved nine centers and aimed to assess potential changes in auditory function as a consequence of exposure to low-intensity electromagnetic fields (EMFs) produced by GSM cellular phones. Participants were healthy young adults without any evidence of hearing or ear disorders. Auditory function was assessed immediately before and after exposure to EMFs, and only the exposed ear was tested. The procedure was conducted twice in a double blinded design, once with a genuine EMF exposure and once with a sham exposure (at least 24 h apart). Tests for assessment of auditory function were hearing threshold level (HTL), transient otoacoustic emissions (TEOAE), distortion product otoacoustic emissions (DPOAE), and auditory brainstem response (ABR). The exposure consisted of speech at a typical conversational level delivered via an earphone to one ear, plus genuine or sham EMF exposure. The EMF exposure used the output of a software-controlled consumer cellular phone at full power for 10 min. A system of phone positioning that allowed participants to freely move their heads without affecting exposure was used. Analysis of the data showed there were no effects of exposure to GSM mobile phone signals on the main measures of the status of the auditory system.