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Koziorowska A, Waszkiewicz EM, Romerowicz-Misielak M, Zglejc-Waszak K, Franczak A. Extremely low-frequency electromagnetic field (EMF) generates alterations in the synthesis and secretion of oestradiol-17β (E 2) in uterine tissues: An in vitro study. Theriogenology 2018; 110:86-95. [PMID: 29353145 DOI: 10.1016/j.theriogenology.2017.12.041] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2017] [Revised: 12/28/2017] [Accepted: 12/29/2017] [Indexed: 10/18/2022]
Abstract
An electromagnetic field (EMF) of extremely low frequency may affect physiological processes in mammals. The aim of the present study was to determine the effect of an EMF on the synthesis and secretion of oestradiol-17β (E2) in the porcine uterus. Endometrial and myometrial slices were harvested on days 12-13 of the oestrous cycle and exposed in vitro to an EMF (50 and 120 Hz, 8 mT) for 2 and 4 h in the presence or absence of progesterone (P4). Subsequently, the incubation media were used to determine the concentration of E2 with RIA. Tissues fragments were used to study the expression of CYP19A3 mRNA using Real-Time PCR and the abundance of P450 aromatase using Western Blotting. The 50-Hz EMF increased E2 release from the endometrium and the myometrium at both time points of in vitro incubation. A 120-Hz EMF decreased the endometrial secretion of E2 after 2 h of incubation and did not affect E2 secretion after 4 h. In the myometrium, the 120-Hz EMF increased E2 secretion after 4 h of incubation. In P4-treated uterine fragments, no significant EMF exposition-related changes were observed. Only myometrial fragments incubated in the presence of P4 at 120-Hz EMF (4 h) released higher amounts of E2 due to EMF treatment. The 50-Hz EMF exposure did not change the CYP19A3 mRNA expression in endometrial fragments incubated in the presence or absence of P4. In myometrial fragments, the highest CYP19A3 mRNA expression was observed in fragments not exposed to the 50-Hz EMF and P4-treated tissues compared to that in fragments exposed to 50 Hz EMF and incubated with or without P4 and control (no EMF and no P4) fragments. The EMF at 120 Hz decreased basal endometrial CYP19A3 mRNA expression and did not change the expression in the P4-treated endometrium. In the myometrium, the EMF at 120 Hz increased CYP19A3 mRNA expression in slices incubated without P4 and had no effect in the presence of P4. The EMF exposure (50 and 120 Hz) did not affect P450 aromatase abundance in either the endometrium or the myometrium. In conclusion, the EMF induces changes in the synthesis and release of E2 in uterine tissues harvested during days 12-13 of the oestrous cycle. These changes are related to the EMF frequency used, the time of the exposition and the presence of P4. We suspect that this observed phenomenon might lead to changes in the intrauterine milieu of oestrogen, which is crucial for the proper activity of uterine tissues during the mid-luteal phase of the oestrous cycle.
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Affiliation(s)
- Anna Koziorowska
- Faculty of Mathematics and Natural Sciences, University of Rzeszow, ul. Rejtana 16c, 35-959 Rzeszow, Poland; Laboratory of Bioelectromagnetism, Institute of Biotechnology, University of Rzeszow, Werynia 502, 36-100 Kolbuszowa, Poland.
| | - Ewa Monika Waszkiewicz
- Department of Animal Physiology, Faculty of Biology and Biotechnology, University of Warmia and Mazury in Olsztyn, Oczapowski Str. 1A, 10-719 Olsztyn, Poland.
| | - Maria Romerowicz-Misielak
- Laboratory of Bioelectromagnetism, Institute of Biotechnology, University of Rzeszow, Werynia 502, 36-100 Kolbuszowa, Poland.
| | - Kamila Zglejc-Waszak
- Department of Animal Physiology, Faculty of Biology and Biotechnology, University of Warmia and Mazury in Olsztyn, Oczapowski Str. 1A, 10-719 Olsztyn, Poland.
| | - Anita Franczak
- Department of Animal Physiology, Faculty of Biology and Biotechnology, University of Warmia and Mazury in Olsztyn, Oczapowski Str. 1A, 10-719 Olsztyn, Poland.
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Dimitrijević D, Savić T, Anđelković M, Prolić Z, Janać B. Extremely low frequency magnetic field (50 Hz, 0.5 mT) modifies fitness components and locomotor activity ofDrosophila subobscura. Int J Radiat Biol 2014; 90:337-43. [DOI: 10.3109/09553002.2014.888105] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
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Kirschenlohr H, Ellis P, Hesketh R, Metcalfe J. Gene expression profiles in white blood cells of volunteers exposed to a 50 Hz electromagnetic field. Radiat Res 2012; 178:138-49. [PMID: 22856684 DOI: 10.1667/rr2859.1] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
Consistent and independently replicated laboratory evidence to support a causative relationship between environmental exposure to extremely low-frequency electromagnetic fields (EMFs) at power line frequencies and the associated increase in risk of childhood leukemia has not been obtained. In particular, although gene expression responses have been reported in a wide variety of cells, none has emerged as robust, widely replicated effects. DNA microarrays facilitate comprehensive searches for changes in gene expression without a requirement to select candidate responsive genes. To determine if gene expression changes occur in white blood cells of volunteers exposed to an ELF-EMF, each of 17 pairs of male volunteers age 20-30 was subjected either to a 50 Hz EMF exposure of 62.0 ± 7.1 μT for 2 h or to a sham exposure (0.21 ± 0.05 μT) at the same time (11:00 a.m. to 13:00 p.m.). The alternative regime for each volunteer was repeated on the following day and the two-day sequence was repeated 6 days later, with the exception that a null exposure (0.085 ± 0.01 μT) replaced the sham exposure. Five blood samples (10 ml) were collected at 2 h intervals from 9:00 to 17:00 with five additional samples during the exposure and sham or null exposure periods on each study day. RNA samples were pooled for the same time on each study day for the group of 17 volunteers that were subjected to the ELF-EMF exposure/sham or null exposure sequence and were analyzed on Illumina microarrays. Time courses for 16 mammalian genes previously reported to be responsive to ELF-EMF exposure, including immediate early genes, stress response, cell proliferation and apoptotic genes were examined in detail. No genes or gene sets showed consistent response profiles to repeated ELF-EMF exposures. A stress response was detected as a transient increase in plasma cortisol at the onset of either exposure or sham exposure on the first study day. The cortisol response diminished progressively on subsequent exposures or sham exposures, and was attributable to mild stress associated with the experimental protocol.
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Affiliation(s)
- Heide Kirschenlohr
- Department of Biochemistry, University of Cambridge, Sanger Building, Cambridge, CB2 1GA, United Kingdom
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Goodman R, Lin-Ye A, Geddis MS, Wickramaratne PJ, Hodge SE, Pantazatos SP, Blank M, Ambron RT. Extremely low frequency electromagnetic fields activate the ERK cascade, increase hsp70 protein levels and promote regeneration in Planaria. Int J Radiat Biol 2010; 85:851-9. [PMID: 19639507 DOI: 10.1080/09553000903072488] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
PURPOSE To use regenerating Planaria Dugesia dorotocethala as a model to determine whether an intermittent modulated extremely low frequency electro-magnetic field (ELF-EMF) produces elevated levels of the heat shock protein hsp70 and stimulates intracellular pathways known to be involved in injury and repair. We focused on serum response element (SRE) binding through the extra-cellular signal-regulated kinase (ERK) cascade. MATERIALS AND METHODS Planaria were transected equidistant between the tip of the head and the tip of the tail. Individual head and tail portions from the same worm were exposed to a 60 Hertz 80 milliGauss ELF-EMF for 1 h twice daily for 15 days post-transection under carefully controlled exposure conditions. The regenerating heads and tails were photographed and the lengths measured at three-day intervals. In other experiments, the timing of the appearance of pigmented eyes was monitored in the tail portion at 12-h intervals following transection in both ELF-EMF exposed and sham control. In some experiments protein lysates were analysed for hsp70 levels, doubly phosphorylated (pp)-ERK, Elk-1 kinase activity and serum response factor (SRF)-SRE binding. RESULTS ELF-EMF exposure during the initial 3-days post-surgery caused a significant increase in regeneration for both heads and tails, but especially tails. The first appearance of eyes occurred at day seven post-transection in tail portions exposed to ELF-EMF. In the sham control tail samples the initial appearance of eyes occurred 48 h later. Concurrently, ELF-EMF-exposed heads and tails exhibited an elevation in the level of hsp70 protein, an activation of an ERK cascade, and an increase in SRF-SRE binding. CONCLUSION Exposures to a modulated sinusoidal ELF-EMF were delivered by a Helmholtz configuration at a frequency of 60 Hz and 80 mG twice a day for one hour. This is accompanied by an increase in hsp70 protein levels, activation of specific kinases and upregulation of transcription factors that are generally associated with repair processes.
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Affiliation(s)
- Reba Goodman
- Department of Pathology, Columbia University, New York, NY 10032, USA.
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Bernabò N, Tettamanti E, Russo V, Martelli A, Turriani M, Mattoli M, Barboni B. Extremely low frequency electromagnetic field exposure affects fertilization outcome in swine animal model. Theriogenology 2010; 73:1293-305. [PMID: 20176397 DOI: 10.1016/j.theriogenology.2009.12.010] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2009] [Revised: 12/23/2009] [Accepted: 12/27/2009] [Indexed: 11/16/2022]
Abstract
Modern society continuously exposes the population to electromagnetic radiation, the effects of which on human health, in particular reproduction, are still unknown. The aim of this research was to assess the effect of acute (1h) exposure of boar spermatozoa to a 50 Hz extremely low frequency electromagnetic field (ELF-EMF) on early fertility outcome. The effect of intensities ranging from 0 to 2 mT on morpho-functional integrity of capacitated spermatozoa was examined in vitro. The oviducts containing or without spermatozoa were then exposed to the minimum in vivo, TD(50,) and maximum intensities determined in vitro, 4h before ovulation. The effects of ELF-EMF on spermatozoa in terms of early embryo development were evaluated after 12h and 6 days. It was found that in vitro ELF-EMF > 0.5 mT induced a progressive acrosome damage, thus compromising the ability of spermatozoa to undergo acrosomal reaction after zona pellucida stimulation and reducing the in vitro fertilization outcome. These effects became evident at 0.75 mT and reached the plateau at 1 mT. Under in vivo conditions, the ELF-EMF intensity of 1 mT was able to compromise sperm function, significantly reducing the fertilization rate. In addition, the exposure of oviducts to fields > or = 0.75 mT in the absence of spermatozoa was able to negatively affect early embryo development. In fact, it was found to cause a slowdown in the embryo cleavage. In conclusion, it was demonstrated how and at which intensities ELF-EMF negatively affect early fertility outcome in a highly predictive animal model.
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Affiliation(s)
- N Bernabò
- Department of Comparative Biomedical Science, University of Teramo, 64100 Teramo, Italy
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Low-frequency pulsed electromagnetic field therapy in fibromyalgia: a randomized, double-blind, sham-controlled clinical study. Clin J Pain 2010; 25:722-8. [PMID: 19920724 DOI: 10.1097/ajp.0b013e3181a68a6c] [Citation(s) in RCA: 55] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
OBJECTIVE To evaluate the clinical effectiveness of low-frequency pulsed electromagnetic field (PEMF) therapy for women with fibromyalgia (FM). METHODS Fifty-six women with FM, aged 18 to 60 years, were randomly assigned to either PEMF or sham therapy. Both the PEMF group (n=28) and the sham group (n=28) participated in therapy, 30 minutes per session, twice a day for 3 weeks. Treatment outcomes were assessed by the fibromyalgia Impact questionnaire (FIQ), visual analog scale (VAS), patient global assessment of response to therapy, Beck Depression Inventory (BDI), and Short-Form 36 health survey (SF-36), after treatment (at 4 wk) and follow-up (at 12 wk). RESULTS The PEMF group showed significant improvements in FIQ, VAS pain, BDI score, and SF-36 scale in all domains at the end of therapy. These improvements in FIQ, VAS pain, and SF-36 pain score during follow-up. The sham group also showed improvement were maintained on all outcome measures except total FIQ scores after treatment. At 12 weeks follow-up, only improvements in the BDI and SF-36 scores were present in the sham group. CONCLUSION Low-frequency PEMF therapy might improve function, pain, fatigue, and global status in FM patients.
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Carbonell MV, Martinez E, Amaya JM. STIMULATION OF GERMINATION IN RICE (ORYZA SATIVAL.) BY A STATIC MAGNETIC FIELD. ACTA ACUST UNITED AC 2009. [DOI: 10.1081/jbc-100100303] [Citation(s) in RCA: 67] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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Alexander MP. Effect of VHF and High-Amplitude Alternating EMF on the Growth of Bacteria(Xanthomonas Campestris). ACTA ACUST UNITED AC 2009. [DOI: 10.3109/15368379609016165] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
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Battini R, Monti MG, Moruzzi MS, Ferrari S, Zaniol P, Barbiroli B. Elf Electromagnetic Fields Affect Gene Expression of Hegenerating Rat Liver Following Partial Hepatectomy. ACTA ACUST UNITED AC 2009. [DOI: 10.3109/15368379109031404] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Affiliation(s)
- R. Battini
- Istituto di Chimica Biologica, Università di Modena, Via Campi 287, 41100, Modena
| | - M. G. Monti
- Istituto di Chimica Biologica, Università di Modena, Via Campi 287, 41100, Modena
| | - M. S. Moruzzi
- Istituto di Chimica Biologica, Università di Modena, Via Campi 287, 41100, Modena
| | - S. Ferrari
- Istituto di Chimica Biologica, Università di Modena, Via Campi 287, 41100, Modena
| | - P. Zaniol
- Istituto di Radiologia, Università di Modena, Via del Pozzo 71, 41100, Modena
| | - B. Barbiroli
- Cattedra di Biologia Molecolare, Università di Bologna, Via Foscolo 7, 40123, Bologna, Italy
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Santini MT, Rainaldi G, Indovina PL. Cellular effects of extremely low frequency (ELF) electromagnetic fields. Int J Radiat Biol 2009; 85:294-313. [PMID: 19399675 DOI: 10.1080/09553000902781097] [Citation(s) in RCA: 62] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
PURPOSE The major areas of research that have characterised investigation of the impact of extremely low frequency (ELF) electromagnetic fields on living systems in the past 50 years are discussed. In particular, selected studies examining the role of these fields in cancer, their effects on immune and nerve cells, and the positive influence of these ELF fields on bone and nerve cells, wound healing and ischemia/reperfusion injury are explored. CONCLUSIONS The literature indicates that there is still no general agreement on the exact biological detrimental effects of ELF fields, on the physical mechanisms that may be behind these effects or on the extent to which these effects may be harmful to humans. Nonetheless, the majority of the in vitro experimental results indicate that ELF fields induce numerous types of changes in cells. Whether or not the perturbations observed at the cellular level can be directly extrapolated to negative effects in humans is still unknown. However, the myriad of effects that ELF fields have on biological systems should not be ignored when evaluating risk to humans from these fields and, consequently, in passing appropriate legislation to safeguard both the general public and professionally-exposed workers. With regard to the positive effects of these fields, the possibility of testing further their efficacy in therapeutic protocols should also not be overlooked.
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Affiliation(s)
- Maria T Santini
- Dipartimento di Ematologia, Oncologia e Medicina Molecolare, Istituto Superiore di Sanita, Viale Regina Elena, Rome.
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George I, Geddis MS, Lill Z, Lin H, Gomez T, Blank M, Oz MC, Goodman R. Myocardial function improved by electromagnetic field induction of stress protein hsp70. J Cell Physiol 2008; 216:816-23. [PMID: 18446816 DOI: 10.1002/jcp.21461] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
Studies on myocardial function have shown that hsp70, stimulated by an increase in temperature, leads to improved survival following ischemia-reperfusion (I-R). Low frequency electromagnetic fields (EMFs) also induce the stress protein hsp70, but without elevating temperature. We have examined the hemodynamic changes in concert with EMF pre-conditioning and the induction of hsp70 to determine whether improved myocardial function occurs following I-R injury in Sprague-Dawley rats. Animals were exposed to EMF (60 Hz, 8 microT) for 30 min prior to I-R. Ischemia was then induced by ligation of left anterior descending coronary artery (LAD) for 30 min, followed by 30 min of reperfusion. Blood and heart tissue levels for hsp70 were determined by Western blot and RNA transcription by rtPCR. Significant upregulation of the HSP70 gene and increased hsp70 levels were measured in response to EMF pre-exposures. Invasive hemodynamics, as measured using a volume conductance catheter, demonstrated significant recovery of systolic contractile function after 30 min of reperfusion following EMF exposure. Additionally, isovolemic relaxation, a measure of ventricular diastolic function, was markedly improved in EMF-treated animals. In conclusion, non-invasive EMF induction of hsp70 preserved myocardial function and has the potential to improve tolerance to ischemic injury.
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Affiliation(s)
- Isaac George
- Department of Surgery, Division of Cardiothoracic Surgery, Columbia University College of Physicians and Surgeons, New York, New York 10032, USA
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Gottwald E, Sontag W, Lahni B, Weibezahn KF. Expression of HSP72 after ELF-EMF exposure in three cell lines. Bioelectromagnetics 2007; 28:509-18. [PMID: 17508393 DOI: 10.1002/bem.20327] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
It has been reported that magnetic fields with flux densities ranging from microT to mT are able to induce heat shock factor, HSP72 mRNA or heat shock proteins in various cells. In this study we investigated changes in the HSP72 mRNA transcription level in three cell lines (HL-60, H9c2, and Girardi heart cells) and in the intracellular HSP72 protein content in two cell lines (HL-60 and Girardi heart cells) after treatment schemes using electromagnetic fields with a flux density of 2 microT to 4 mT, a frequency of 50 Hz and exposure times from 15 to 30 min. None of the treatments or modalities showed any significant effect on the HSP72 protein level, although HSP72 mRNA could be induced, at least to some extent, with one of the parameter combinations in all cell lines tested. Obviously, HSP72 mRNA transcription and translation are not necessarily coupled in certain cells. This leads to the conclusion that electromagnetic field effects on HSP72 mRNA levels are not indicative for downstream effects unless increased mRNA levels can be correlated with increased HSP72 protein levels as well.
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Affiliation(s)
- Eric Gottwald
- Forschungszentrum Karlsruhe, Institut für Biologische Grenzflächen, Eggenstein-Leopoldshafen, Germany.
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Bernabò N, Tettamanti E, Pistilli MG, Nardinocchi D, Berardinelli P, Mattioli M, Barboni B. Effects of 50 Hz extremely low frequency magnetic field on the morphology and function of boar spermatozoa capacitated in vitro. Theriogenology 2006; 67:801-15. [PMID: 17196643 DOI: 10.1016/j.theriogenology.2006.10.014] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2006] [Revised: 10/03/2006] [Accepted: 10/04/2006] [Indexed: 11/17/2022]
Abstract
The aim of this study was to evaluate the effect of an acute exposure to a sinusoidal MF-ELF (50 Hz, 1mT) on the ability of boar mature spermatozoa to acquire the fertilizing competence in vitro. The spermatozoa exposed during the 4h of incubation to the MF-ELF were evaluated for morphological (surface morphology and acrosome integrity) and functional parameters (cell viability, motility, induction of acrosomal reaction, AR, and the ability to in vitro fertilize oocytes). In parallel, the intracellular Ca(2+) levels as well as the major mechanisms of Ca(2+) clearance were assessed: (45)Ca intakes and intracellular Ca(2+) sequestration by analyzing intracellular Ca(2+) elevation induced by thapsigargin or studying mitochondrial function with Mito-Tracker. The MF-ELF exposure did not affect sperm viability and morphology during the first h of incubation when sperm Ca(2+) homeostasis were already compromised. First of all, MF-ELF treated spermatozoa showed resting intracellular Ca(2+) levels significantly lower than those recorded in controls. This result was dependent on a lower extracellular Ca(2+) intake and from the inhibitory role exerted on both intracellular Ca(2+) storages. As a consequence, after 1h of incubation MF-ELF exposed cells displayed a reduced motility, a modest reactivity when coincubated with solubilized zonae pellucidae and a reduction in oocyte penetrating ability. After 2 or 4h of incubation, in addition, signs of morphological damage appeared on plasma membrane and at acrosomal level. In conclusion, MF-ELF influence negatively spermatozoa first by impairing cell Ca(2+) homeostasis then by dramatically affecting sperm morphology and function.
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Affiliation(s)
- N Bernabò
- Institute of Physiology, Department of Biomedical Science, P.zza Aldo Moro 45, Teramo, Italy
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Kelleher MO, Al-Abri RK, Lenihan DV, Glasby MA. Use of a static magnetic field to promote recovery after peripheral nerve injury. J Neurosurg 2006; 105:610-5. [PMID: 17044566 DOI: 10.3171/jns.2006.105.4.610] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Object
While pulsed electromagnetic stimulation has been shown to enhance peripheral nerve regeneration, the effect of a static magnetic field on nerve repair is less clear. The aim of this study was to establish what effect an imposed exogenous static magnetic field has on peripheral nerve regeneration after transection and repair.
Methods
Three groups of six adult sheep were used. The first group acted as normal controls. In the second group, the median nerve was divided and immediately repaired by entubulation within a “controlled-release” biodegradable glass tube. In the third group, small magnets were applied to the sides of the biodegradable glass tubes before the median nerve was repaired using these magnetic tubes. The sheep were allowed to recover and were reexamined 10 months later. The animals underwent comprehensive morphometric (cross-sectional morphometry and measurement of internodal lengths), electrophysiological (determinations of stimulated jitter, maximum conduction velocity, refractory period, and F waves), and isometric tension (isometric twitch and tetanic tension) assessments.
Conclusions
Exogenously applied static electromagnetic fields do not enhance peripheral nerve regeneration.
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Affiliation(s)
- Michael O Kelleher
- National Neurosurgical Unit, Beaumont Hospital, Dublin, Republic of Ireland.
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Yokus B, Cakir DU, Akdag MZ, Sert C, Mete N. Oxidative DNA damage in rats exposed to extremely low frequency electro magnetic fields. Free Radic Res 2005; 39:317-23. [PMID: 15788236 DOI: 10.1080/10715760500043603] [Citation(s) in RCA: 77] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
Extremely low frequency (ELF) electromagnetic field (EMF) is thought to prolong the life of free radicals and can act as a promoter or co-promoter of cancer. 8-hydroxy-2'-deoxyguanosine (8OHdG) is one of the predominant forms of radical-induced lesions to DNA and is a potential tool to asses the cancer risk. We examined the effects of extremely low frequency electro magnetic field (ELF-EMF) (50 Hz, 0.97 mT) on 8OHdG levels in DNA and thiobarbituric acid reactive substances (TBARS) in plasma. To examine the possible time-dependent changes resulting from magnetic field, 8OHdG and TBARS were quantitated at 50 and 100 days. Our results showed that the exposure to ELF-EMF induced oxidative DNA damage and lipid peroxidation (LPO). The 8OHdG levels of exposed group (4.39+/-0.88 and 5.29+/-1.16 8OHdG/dG.10(5), respectively) were significantly higher than sham group at 50 and 100 days (3.02+/-0.63 and 3.46+/-0.38 8OHdG/dG.10(5)) (p<0.001, p<0.001). The higher TBARS levels were also detected in the exposure group both on 50 and 100 days (p<0.001, p<0.001). In addition, the extent of DNA damage and LPO would depend on the exposure time (p<0.05 and p<0.05). Our data may have important implications for the long-term exposure to ELF-EMF which may cause oxidative DNA damage.
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Affiliation(s)
- Beran Yokus
- Department of Biochemistry, Faculty of Veterinary, Dicle University, 21280 Diyarbakir, Turkey.
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Sutbeyaz ST, Sezer N, Koseoglu BF. The effect of pulsed electromagnetic fields in the treatment of cervical osteoarthritis: a randomized, double-blind, sham-controlled trial. Rheumatol Int 2005; 26:320-4. [PMID: 15986086 DOI: 10.1007/s00296-005-0600-3] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2004] [Accepted: 01/30/2005] [Indexed: 10/25/2022]
Abstract
The purpose of this study was to evaluate the effect of electromagnetic field therapy (PEMF) on pain, range of motion (ROM) and functional status in patients with cervical osteoarthritis (COA). Thirty-four patients with COA were included in a randomized, double-blind study. PEMF was administrated to the whole body using a mat 1.8 x 0.6 m in size. During the treatment, the patients lay on the mat for 30 min per session, twice a day for 3 weeks. Pain levels in the PEMF group decreased significantly after therapy (p<0.001), but no change was observed in the placebo group. The active ROM, paravertebral muscle spasm and neck pain and disability scale (NPDS) scores improved significantly after PEMF therapy (p<0.001) but no change was observed in the sham group. The results of this study are promising, in that PEMF treatment may offer a potential therapeutic adjunct to current COA therapies in the future.
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Affiliation(s)
- Serap Tomruk Sutbeyaz
- Ankara Physical Medicine and Rehabilitation Education and Research Hospital, Turk ocagi S No: 3 Sihhiye, Ankara, Turkey
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Sommer AM, Lerchl A. The risk of lymphoma in AKR/J mice does not rise with chronic exposure to 50 Hz magnetic fields (1 microT and 100 microT). Radiat Res 2004; 162:194-200. [PMID: 15387147 DOI: 10.1667/rr3219] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
Some epidemiological studies suggest that exposure to 50 or 60 Hz magnetic fields might increase the risk of leukemia, especially in children with a comparable high residential exposure. To investigate this possibility experimentally, the influence of 50 Hz magnetic-field exposure on lymphoma induction was determined in a mouse strain that is genetically predisposed to this disease. The AKR/J mouse genome carries the AK virus, which leads within 1 year to spontaneous development of thymic lymphoblastic lymphoma. Beginning at an age of 4-5 weeks, groups of 160 female mice were sham-exposed or exposed to 50 Hz magnetic fields at 1 or 100 microT for 24 h per day, 7 days per week, for 38 weeks. Animals were checked visually daily and were weighed and palpated weekly. There was no effect of magnetic-field exposure on body weight gain or survival rate, and lymphoma incidence did not differ between exposed and sham-exposed animals. Therefore, these data do not support the hypothesis that chronic exposure to 50 Hz magnetic fields is a significant risk factor for developing hematopoietic malignancy.
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Affiliation(s)
- Angela M Sommer
- School of Engineering and Science, International University Bremen, Bremen, Germany
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Henderson BR, Pfister G, Boeck G, Kind M, Wick G. Expression levels of heat shock protein 60 in human endothelial cells in vitro are unaffected by exposure to 50 Hz magnetic fields. Cell Stress Chaperones 2004; 8:172-82. [PMID: 14627203 PMCID: PMC514869 DOI: 10.1379/1466-1268(2003)008<0172:elohsp>2.0.co;2] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
Magnetic fields (MFs) from domestic power sources have been implicated as being a potential risk to human health. A number of epidemiological studies have found a significant link between exposure to MFs and increased rates of cancers. There have also been a number of in vivo and in vitro studies reporting effects of MFs in animal disease models and on the expression or activity of a range of proteins. In the past decade, our group proposed that atherosclerosis may have an autoimmune component, with heat shock protein 60 (Hsp60) expressed in endothelial cells as the dominant autoantigen. A number of stressors have been shown to induce the expression of Hsp60, including the classical risk factors for atherosclerosis. We were interested to see if the exposure of endothelial cells to an MF elicited increased expression of Hsp60, as has been reported previously for Hsp70. The present work describes the exposure of endothelial cells to domestic power supply (50 Hz) MFs at an intensity of 700 microT. The results from our system indicate that cultured endothelial cells exposed to a high intensity of MF either alone or in combination with classical heat stress show no effects on the expression of Hsp60 at either the messenger ribonucleic acid or the protein level. As such, there is no evidence that exposure to extremely low-frequency MF would be expected to increase the expression of Hsp60 and therefore the initiation or progression of atherosclerosis.
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Affiliation(s)
- B R Henderson
- Institute of Biomedical Aging Research, Austrian Academy of Science, Rennweg 10, A-6020 Innsbruck, Austria
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19
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Hsu SF, Lin JG, Liu HJ, Lai IL, Wu SL, Hsiangt CY, Hot TY. Activation of activator protein-1 in cells exposed to electrical stimulation of various parameters used in electroacupuncture therapy. THE AMERICAN JOURNAL OF CHINESE MEDICINE 2004; 31:967-75. [PMID: 14992548 DOI: 10.1142/s0192415x03001508] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
The aim of this study was to investigate the effect of electrical stimulation on activator protein-1 (AP-1) in recombinant liver cells. In order to elucidate the molecular effects of electrical stimulation on cells, AP-1 expression was detected by a luciferase assay. The parameters used were taken from clinical electroacupuncture (EA) therapy as follows: biphasic rectangular symmetrical pulses (frequency: 2, 10 and 100 Hz; pulse width: 50, 80, 130 and 250 microsec; intensity: 1, 2, 5 and 10 mA; time: 5, 10, 20 and 30 minutes). S (10% fetal bovine serum in medium), SF (serum free medium) and 12-O-tetradecanoylphorbol-13-acetate (TPA) treatment represented the experimental, negative and positive groups, respectively. We found that electrical stimulation with 10 Hz, a pulse width of 130 microsec, and a duration of 30 minutes gave a significant increase in AP-1 activity. In contrast, the intensity of the stimulation had no significant effect on AP-1 activity. In conclusion, our data suggest that electrical stimulation with an appropriate frequency, duration and pulse width could cause an increase in AP-1 activity in cells.
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Affiliation(s)
- Sheng-Feng Hsu
- Acupuncture Department, China Medical University Hospital, School of Chinese Medicine, China Medical University Taichung, Taiwan, ROC
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20
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Saxena A, Jacobson J, Yamanashi W, Scherlag B, Lamberth J, Saxena B. A hypothetical mathematical construct explaining the mechanism of biological amplification in an experimental model utilizing picoTesla (PT) electromagnetic fields. Med Hypotheses 2003; 60:821-39. [PMID: 12699707 DOI: 10.1016/s0306-9877(03)00011-2] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
We seek to answer the conundrum: What is the fundamental mechanism by which very weak, low frequency Electromagnetic fields influence biosystems? In considering the hydrophobicity of intramembranous protein (IMP) H-bonds which cross the phospholipid bilayer of plasma membranes, and the necessity for photonic recycling in cell surface interactions after dissipation of energetic states, present models lack structure and thermodynamic properties to maintain (DeltaE) sufficient energy sources necessary for amplifications by factors of 10(12). Even though one accepts that the ligand-receptor association alters the conformation of extracellular, extruding portions of IMP's at the cell surface, and that this change can be transmitted to the cytoplasm by the transmembranous helical segments by nonlinear vibrations of proteins with generation of soliton waves, one is still unable to account for repair and balanced function. Indeed, responses of critical molecules to certain magnetic field signals may include enhanced vibrational amplitudes, increased quanta of thermal energies and order inducing interactions. We may accept that microtrabecular reticulum-receptor is associated with actin filaments and ATP molecules which contribute to the activation of the cyclase enzyme system through piezoelectricity. Magnetic fields will pass through the membrane which sharply attenuates the electric field component of an EM field, due to its high impedance. Furthermore, EM oscillations are converted to mechanical vibrations; i.e., photon-phonon transduction, to induce molecular vibrations of frequencies specifically responsible for bioamplifications of weak triggers at the membrane surface, as well as GAP junctions. The hydrogen bonds of considerable importance are those in proteins (10(12)Hz) and DNA (10(11)Hz) and may be viewed as centers of EM radiation emission in the range from the mm microwaves to the far IR. However, classical electrodynamical theory does not yield a model for biomolecular resonant responses which are integrated over time and account for the connection between the phonon field and photons. Jacobson Resonance does supply an initial physical mechanism, as equivalencies in energy to that of Zeeman Resonance (i.e., zero-order magnetic resonance) and cyclotron resonance may be derived from the DeBroglie wave particle equation. For the first time, we view the introduction of Relativity Theory to biology in the expression, mc(2)=BvLq, where m is the mass of a particle in the 'box' or 'string' (molecule in a biosystem), c is the velocity of electromagnetic field in space, independent of its inertial frame of reference, B is the magnetic flux density,v is the velocity of the carrier or 'string' (a one or two dimensional 'box') in which the particle exists, L is its dimension (length) and q represents a unit charge q=1C, by defining electromotive force as energy per unit charge. Equivalencies suggest that qvBL is one of the fundamental expressions of energy of a charged wave-particle in magnetic fields, just as Zeeman and cyclotron resonance energy expressions, gbetaB and qhB/2pim, and is applicable to all charged particles (molecules in biological systems). There may exist spontaneous, independent and incessant interactions of magnetic vector B and particles in biosystems which exert Lorentz forces. Lorentz forces may be transmitted from EM field to gravitational field as a gravity wave which return to the phonon field as microgravitational fluctuations to therein produce quantum vibrational states that increase quanta of thermal energies integrated over time. This may account for the differential of 10(12) between photonic energy of ELF waves and the Boltzman energy kT. Recent data from in vivo controlled studies are included as empirical support for the various hypotheses presented.
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Affiliation(s)
- Anjali Saxena
- Department of Biological Sciences, Fairleigh Dickinson University, 1000 River Road, Teaneck, New Jersey 07666, USA
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21
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Rao RR, Kisaalita WS. A single magnetic field exposure system for sequential investigation of real time and downstream cellular responses. Bioelectromagnetics 2003; 25:27-32. [PMID: 14696050 DOI: 10.1002/bem.10151] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
To be able to correlate real time membrane potential or ion flux changes with further downstream gene transcription responses due to extremely low frequency (ELF) electromagnetic field (EMF) exposure, we devised an experimental system consisting of a pair of symmetric circular coils. This system can be used on an inverted microscope stage (real time signaling) as well as inside controlled environment incubators (gene transcription end points). The system includes a unique, custom made switch box for blinding the experimental staff and a power amplifier. We report herein the design and characterization of the system with respect to parameters considered important in in vitro ELF-EMF exposure studies, including linear magnetic field distribution, compensation for microscope objective lens interference, heating effects of the coils, and harmonic content of the signals.
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Affiliation(s)
- Raj R Rao
- Cellular Bioengineering Laboratory, Biological & Agricultural Engineering Department, University of Georgia, Athens, Georgia 30602, USA
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22
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Yoshizawa H, Tsuchiya T, Mizoe H, Ozeki H, Kanao S, Yomori H, Sakane C, Hasebe S, Motomura T, Yamakawa T, Mizuno F, Hirose H, Otaka Y. No effect of extremely low-frequency magnetic field observed on cell growth or initial response of cell proliferation in human cancer cell lines. Bioelectromagnetics 2002; 23:355-68. [PMID: 12111756 DOI: 10.1002/bem.10006] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
An effect on the tumor promotion process, as represented by accelerated cell growth, has been indicated as one example of areas that demonstrate the possibility of biological effects of extremely-low frequency magnetic fields. We, therefore, exposed the five cell lines (HL-60, K-562, MCF-7, A-375, and H4) derived from human tumors to a magnetic field for 3 days to investigate the effects on cell growth. Prior to exposure or sham exposure, the cells were precultured for 2 days in low serum conditions. The number of growing cells was counted in a blind manner. To investigate the effect on the initial response of cell proliferation, two cell lines were synchronized in G1 phase by serum starvation and then exposed to a magnetic field for 18 h (H4 cells) or 24 h (MCF-7 cells), both with and without serum stimulation. The rate of DNA synthesis, taken as a measure of the cell proliferation, was determined by following the incorporation of [(3)H]-thymidine into the DNA. Three different magnetic field polarizations at both 50 and 60 Hz were used: linearly polarized (vertical); circularly polarized; and an elliptically polarized field. Magnetic field flux densities were set at 500, 100, 20 and 2 microT (rms) for the vertical field and at 500 microT (rms) for the rotating fields. No effect of magnetic field exposure was observed on either cell growth or the initial response of cell proliferation.
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Affiliation(s)
- Hiroaki Yoshizawa
- Power Engineering R & D Center, Tokyo Electric Power Co., Inc., Yokohama, Japan
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23
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Zhou J, Li C, Yao G, Chiang H, Chang Z. Gene expression of cytokine receptors in HL60 cells exposed to a 50 Hz magnetic field. Bioelectromagnetics 2002; 23:339-46. [PMID: 12111754 DOI: 10.1002/bem.10027] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
The effects of a 50 Hz extremely low frequency (ELF) sinusoidal magnetic field (MF) on the expression of genes relating to cytokine receptors were studied in HL60 cells. Transcription levels of tumor necrosis factor receptor (TNFR) p55 and p75, interleukin-6 receptor-alpha (IL-6Ralpha) and transforming growth factor-beta receptor 1 (TGFbetaR1) were quantified in cells exposed to an intensity of 0.1 or 0.8 mT for periods ranging from 30 min to 72 h. Cells treated with 10 nM of phorbol 12-myristate 13-acetate (PMA) for 8 h served as a positive control. Gene expression values were assessed by the ribonuclease protection assay (RPA) and normalized to those of the noninducible gene GAPDH. The results showed that MF exposure at 0.1 and 0.8 mT for 72 h increased TNFR p75 and IL-6Ralpha mRNA expression in HL60 cells. No significant change in gene expression levels of TNFR p55 and TGFbetaR1 was observed under any of the exposure conditions. In addition, we report here for the first time that IL-6Ralpha mRNA expression can be suppressed by PMA in HL60 cells.
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MESH Headings
- Activin Receptors, Type I/genetics
- Antigens, CD/genetics
- Gene Expression/drug effects
- HL-60 Cells
- Humans
- Magnetics/adverse effects
- Protein Serine-Threonine Kinases
- RNA, Messenger/genetics
- RNA, Messenger/metabolism
- Receptor, Transforming Growth Factor-beta Type I
- Receptors, Cytokine/genetics
- Receptors, Interleukin-6/genetics
- Receptors, Transforming Growth Factor beta/genetics
- Receptors, Tumor Necrosis Factor/genetics
- Receptors, Tumor Necrosis Factor, Type I
- Receptors, Tumor Necrosis Factor, Type II
- Tetradecanoylphorbol Acetate/pharmacology
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Affiliation(s)
- Jiliang Zhou
- Institute of Biochemistry and Cell Biology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai, People's Republic of China
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24
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Rao RR, Halper J, Kisaalita WS. Effects of 60 Hz electromagnetic field exposure on APP695 transcription levels in differentiating human neuroblastoma cells. Bioelectrochemistry 2002; 57:9-15. [PMID: 12049751 DOI: 10.1016/s1567-5394(02)00004-x] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
Epidemiological studies have suggested that workers with primary occupation that are likely to have resulted in the medium-to-high extremely low frequency (ELF) electromagnetic field (EMF) exposure are at increased risk of Alzheimer's disease (AD) pathogenesis. As a first step in investigating the possibility of an association between the ELF-EMF exposure and AD at the cellular level, we have used the differentiating IMR-32 neuroblastoma cells. In double-blind experiments, IMR-32 cells were exposed to the magnetic field intensities of 50, 100, and 200 microT at a frequency of 60 Hz for a period of 4 h at the three ages of differentiation (2, 10, and 16 days after incubation in differentiation medium). We used a custom-made Helmholtz coil setup driven by a 60-Hz sinusoidal signal from a function generator and an in-house built power amplifier. Total RNA extracted from the exposed cells was separated by the agarose gel electrophoresis and transferred to a nylon membrane for the northern hybridization. Digoxygenin-labeled APP695 RNA probes were used to detect changes in the APP695 mRNA levels in response to the ELF-EMF exposure. The results reported herein provided no support for any relationship between the APP695 gene transcription and IMR-32 differentiation age, as well as the magnetic field exposure. This study constitutes the first step towards investigating the possibility of an association between the ELF-EMF exposure and AD manifestations at the cellular level.
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Affiliation(s)
- Raj R Rao
- Cellular Bioengineering Laboratory, Biological and Agricultural Engineering Department, University of Georgia, Athens, GA 30602, USA
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25
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Yomori H, Yasunaga K, Takahashi C, Tanaka A, Takashima S, Sekijima M. Elliptically polarized magnetic fields do not alter immediate early response genes expression levels in human glioblastoma cells. Bioelectromagnetics 2002; 23:89-96. [PMID: 11835255 DOI: 10.1002/bem.101] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
Expression of immediate early response genes such as c-fos, c-jun, and c-myc in response to 1-500 microT resultant (r) 60 Hz elliptically polarized (EP) magnetic fields (MFs), typical of environmental MFs polarization under overhead power lines, was analyzed in both at transcriptional and translational levels using human glioblastoma (T98G) cells. Pseudo synchronized T98G cells at G1 phase were exposed to EP-MFs (1, 20, 100, and 500 microTr) for up to 3 h, but produced no statistical difference (P>0.05) in the levels of expression ratio at both the transcriptional and translational levels at 30 min for c-fos and c-jun and at 180 min for c-myc after serum stimulation. In addition, exposure of T98G cells to linearly (vertical and horizontal) and/or circularly polarized MFs (500 microTr) produced no significant change (P>0.05) in the expression ratio at both transcriptional and post-transcriptional levels. Thus, there was no evidence that linearly or rotating polarized MFs enhanced early response gene expression in these studies. These results suggest that environmental MFs at 1-500 microT flux density are unlikely to induce carcinogenesis through a mechanism involving altered expression of the immediate early response genes.
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MESH Headings
- Blotting, Northern
- Brain Neoplasms/genetics
- Electromagnetic Fields
- Gene Expression Regulation/radiation effects
- Genes, fos/genetics
- Genes, fos/radiation effects
- Genes, jun/genetics
- Genes, jun/radiation effects
- Genes, myc/genetics
- Genes, myc/radiation effects
- Glioblastoma/genetics
- Humans
- RNA Processing, Post-Transcriptional/radiation effects
- RNA, Ribosomal/genetics
- RNA, Ribosomal/metabolism
- Transcription, Genetic/radiation effects
- Tumor Cells, Cultured
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Affiliation(s)
- Hiroyuki Yomori
- Technical Research Center, The Kansai Electric Power Company, Inc., Hyogo, Japan
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26
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Marino AA, Wolcott RM, Chervenak R, Jourd'heuil F, Nilsen E, Frilot C. Nonlinear dynamical law governs magnetic field induced changes in lymphoid phenotype. Bioelectromagnetics 2001; 22:529-46. [PMID: 11748671 DOI: 10.1002/bem.82] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
The results of many different types of animal and human studies dealing with the biological effects of exposure to low frequency electromagnetic fields (EMFs) have consistently been both positive and negative. We addressed the question of why this pattern had occurred so commonly in biological studies involving exposure to EMFs and hypothesized that it stemmed from the prevalent use of a linear model to characterize what are inherently nonlinear input-output relationships. The hypothesis was tested by analyzing biological data using a novel statistical procedure that could be adjusted to detect either nonlinear or linear effects. The reliability of the procedure was established using positive and negative controls and by comparison with the results obtained from sampling a known nonlinear system. In four independent experiments, male and female mice were exposed continuously to 0.1 or 0.5 mT, 60 Hz, for 175 days, and the effect on 20 immune parameters was measured using flow cytometry and functional assays. In each experiment, EMF exposure resulted in statistically significant changes in lymphoid phenotype when and only when the response of the animals to the fields was analyzed as if it were governed by nonlinear laws. Our results suggest that the pattern of inconsistency in the EMF bioeffects studies is an artifact resulting from an incorrect choice of the conceptual model for the relation between the field and the biological effect it causally determines.
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Affiliation(s)
- A A Marino
- Department of Orthopaedic Surgery, LSU Health Sciences Center, Shreveport, Louisiana 71130-3932, USA.
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27
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Wu RY, Chiang H, Hu GL, Zeng QL, Bao JL. The effect of 50 Hz magnetic field on GCSmRNA expression in lymphoma B cell by mRNA differential display. J Cell Biochem 2000; 79:460-70. [PMID: 10972983 DOI: 10.1002/1097-4644(20001201)79:3<460::aid-jcb110>3.0.co;2-t] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
Magnetic fields (MFs) of various characteristics can lead to plethora effects in biological system. From a molecular point of view, we hypothesized that there must be a fundamental difference in gene expression between the MF exposed and the unexposed cell. To identify the classes of genes that are regulated, 0.8 mT 50 Hz MF-induced changes in gene expression were examined in a Daudi cell culture using differential display and reverse transcriptase-polymerase chain reaction. A candidate cDNA (signatured as MF-CB) that was observed in the sham-exposed but not in MF-exposed cultures was recovered and reamplified. After verification by Northern blot, the cDNA was cloned and sequenced. It was found that 254-base pair of 5'-end MF-CB cDNA clone was identical to gcs in open reading frame (ORF) range. Based on the preliminarily sequence, the prolonged length of 5'-end MF-CB cDNA was obtained by PCR amplification and its sequence analysis showed the same results as its original fragment. In order to further determine whether MF-CB cDNA is from gcs, two Northern blots were probed with gcs and MF-CB cDNA, respectively, and the data revealed signals of the same size and expression pattern on the two probe filters, which demonstrated that MF-CB is an EST (expression sequence tag) of gcs. gcs is a gene, identified recently (GenBank accession number D89866), encoding ceramide glucosyltransferase (GCS), which has been implicated as a causal element in human cell growth and differentiation. In an additional experiment, time-dependent changes in the transcription of gcs induced by 0.8 mT MF were observed by Northern blot with a sharp and reproducible inhibition effect after 20 min exposure and a reduction after 20-24 h exposure. The study demonstrates for the first time that 50 Hz MF can lead to changes in gcs transcription, which provides a new clue to elucidate the mechanism by which MF influence cell growth and differentiation.
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MESH Headings
- Amino Acid Sequence
- Base Sequence
- Blotting, Northern
- Burkitt Lymphoma/genetics
- Burkitt Lymphoma/pathology
- Cloning, Molecular
- DNA, Complementary/genetics
- Enzyme Induction/radiation effects
- Gene Expression Profiling
- Gene Expression Regulation, Neoplastic/radiation effects
- Glucosyltransferases/biosynthesis
- Glucosyltransferases/genetics
- Humans
- Magnetics
- Molecular Sequence Data
- Neoplasm Proteins/biosynthesis
- Neoplasm Proteins/genetics
- Polymerase Chain Reaction
- RNA, Messenger/biosynthesis
- RNA, Neoplasm/biosynthesis
- Sequence Homology, Nucleic Acid
- Subtraction Technique
- Transcription, Genetic/radiation effects
- Tumor Cells, Cultured/metabolism
- Tumor Cells, Cultured/radiation effects
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Affiliation(s)
- R Y Wu
- Microwave Lab, Medical College, Zhejiang University, Hangzhou 310031, P.R. China
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28
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Heermeier K, Spanner M, Träger J, Gradinger R, Strauss PG, Kraus W, Schmidt J. Effects of extremely low frequency electromagnetic field (EMF) on collagen type I mRNA expression and extracellular matrix synthesis of human osteoblastic cells. Bioelectromagnetics 2000; 19:222-31. [PMID: 9581965 DOI: 10.1002/(sici)1521-186x(1998)19:4<222::aid-bem4>3.0.co;2-3] [Citation(s) in RCA: 51] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Human osteoblastic cells were grown in a three-dimensional (3-D) cell culture model and used to test the effects of a 20 Hz sinusoidal electromagnetic field (EMF; 6 mT and 113 mV/cm max) on collagen type I mRNA expression and extracellular matrix formation in comparison with the effects of growth factors. The cells were isolated from trabecular bone of a healthy individual (HO-197) and from a patient presenting with myositis ossificans (MO-192) and grown in a collagenous sponge-like substrate. Maximal enhancement of collagen type I expression after EMF treatment was 3.7-fold in HO-197 cells and 5.4-fold in MO-192 cells. Similar enhancement was found after transforming growth factor-beta (TGF-beta) and insulin-like growth factor-I (IGF-I) treatment. Combined treatment of the cells with EMF and the two growth factors TGF-beta and IGF-I did not act synergistically. MO-192 cells produced an osteoblast-characteristic extracellular matrix containing collagen type I, alkaline phosphatase, and osteocalcin, together with collagen type III, TP-1, and TP-3, two epitopes of an osteoblastic differentiation marker. The data suggest that the effects of EMFs on osteoblastic differentiation are comparable to those of TGF-beta and IGF-I. We conclude that EMF effects in the treatment of skeletal disorders and in orthopedic adjuvant therapy are mediated via enhancement of collagen type I mRNA expression, which may lead to extensive extracellular matrix synthesis.
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Affiliation(s)
- K Heermeier
- Institut für Molekulare Virologie, GSF-Forschungszentrum für Umwelt und Gesundheit, Neuherberg, Germany
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29
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Davis CC, Barber I, Swicord ML. Food and Drug Administration low-level extremely-low-frequency magnetic field exposure facility. Bioelectromagnetics 2000; 20:203-15. [PMID: 10230934 DOI: 10.1002/(sici)1521-186x(1999)20:4<203::aid-bem1>3.0.co;2-l] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
We describe the design, construction details, and performance characteristics of an exposure system designed to provide very well controlled extremely-low-frequency magnetic field exposures of in vitro samples. This system uses Helmholtz coils placed inside temperature-controlled mu-metal chambers to provide simultaneous ac and dc field exposures at any relative angle with minimal residual background field. The system has both exposed and sham-exposed chambers and is operated under computer control in such a way as to ensure blind exposure of samples.
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Affiliation(s)
- C C Davis
- Electrical Engineering Department, University of Maryland, College Park 20742, USA
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30
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Korneva HA, Grigoriev VA, Isaeva EN, Kaloshina SM, Barnes FS. Effects of low-level 50 Hz magnetic fields on the level of host defense and on spleen colony formation. Bioelectromagnetics 2000; 20:57-63. [PMID: 9915594 DOI: 10.1002/(sici)1521-186x(1999)20:1<57::aid-bem8>3.0.co;2-7] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
The results of 3 sets of experiments on the effects of 22 microT sinusoidal 50 Hz magnetic fields (MF), applied for 1 h on 5 successive days (1 h/5 days), on the level of host defense and on spleen colony formation are reported. The first set of experiments shows the effects on the number of colony-forming units (CFUs) on the spleen and on the cellularity of the thymus in mice. The MF exposures resulted in an increase in CFUs which was statistically significant with respect to the controls, but not with respect to the shams. Statistically significant changes in the thymic weight and thymic index with respect to both the controls and the shams were measured 1 h after the last MF exposure. In the second set of experiments, the mice were given a sublethal dose of X-rays (6 Gy), which was followed by exposure 2 h later to the MF. The MF exposure was repeated at the same time of day for 5 days. The number of colonies per spleen showed a consistent, statistically significant increase with MF exposure and the number of CFUs per femur was decreased. In the third set of experiments, bone marrow was taken from mice which had been exposed to 22 microT fields and injected into mice which had been exposed to a lethal dose of X-rays (9 Gy). The number of CFUs per femur in the recipient mice was shown to be reduced by a statistically significant amount at 1 and 4 days after injection.
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Affiliation(s)
- H A Korneva
- Department of General Pathology and Pathophysiology, Institute for Experimental Medicine, St. Petersburg, Russia
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31
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Boorman GA, Owen RD, Lotz WG, Galvin MJ. Evaluation of in vitro effects of 50 and 60 Hz magnetic fields in regional EMF exposure facilities. Radiat Res 2000; 153:648-57. [PMID: 10790288 DOI: 10.1667/0033-7587(2000)153[0648:eoiveo]2.0.co;2] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
A weak association between magnetic-field exposure and increased incidences of cancer has been reported. While alterations in cellular processes after in vitro magnetic-field exposures have also been reported to provide plausibility for this association, other laboratories have been unable to repeat the findings. As part of an accelerated electric- and magnetic-field (EMF) research program, the National Institute of Environmental Health Sciences with the Department of Energy identified the replication of the published positive effects as a priority. Regional EMF exposure facilities were established to investigate major in vitro effects from the literature. These included effects on gene expression, intracellular calcium, colony growth in soft agar, and ornithine decarboxylase activity. The laboratories that first reported these effects provided experimental protocols, cell lines, and other relevant experiment details. Regional facility studies included sham/sham exposures (no applied field in either chamber) and were done in a blinded fashion to minimize investigator bias. In nearly all experiments, no effects of magnetic-field exposure were found. The effort provided insight into dealing with the difficulty of replication of subtle effects in complex biological systems. Experimental techniques provided some clues for the differences in experimental results between the regional facility and the original investigator. Studies of subtle effects require extraordinary efforts to confirm that the effect can be attributed to the applied exposure.
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Affiliation(s)
- G A Boorman
- National Institute of Environmental Health Sciences, P.O. Box 12233, Research Triangle Park, North Carolina 27709, USA
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Morehouse CA, Owen RD. Exposure of Daudi cells to low-frequency magnetic fields does not elevate MYC steady-state mRNA levels. Radiat Res 2000; 153:663-9. [PMID: 10790290 DOI: 10.1667/0033-7587(2000)153[0663:eodctl]2.0.co;2] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
The effect of extremely low-frequency electromagnetic field (ELF EMF) exposures to human health has been widely debated. Epidemiological studies have found a possible correlation between increased cancer incidence and environmental ELF EMF exposures. Results from in vitro studies performed to examine the possible underlying bioeffects of ELF EMFs have varied greatly. Reported effects range from robust and reproducible effects to undetectable. In this study, Daudi cells were exposed to 60 Hz magnetic fields for 20, 40 or 60 min at flux densities of 12.5, 50, 100 or 500 microT. Exposures were performed in the Regional ELF-EMF Exposure Facility (Rockville, MD) to minimize variables that might contribute to a false positive effect. Exposures included sham/sham, exposed/sham or sham/exposed, and were performed with blinding with respect to type of exposure. 12-O-Tetradecanoylphorbol-13-acetate (TPA) treatment was used as a positive control. Total cellular RNA was isolated using a single-step technique. Human MYC expression was measured by northern blot hybridization as an indicator of the responsiveness of Daudi cells to experimental conditions. Beta-2-microglobulin (B2M) expression was measured simultaneously as an internal control. Exposure to a 60 Hz magnetic field did not significantly alter MYC expression in Daudi cells under any of the exposure conditions.
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Affiliation(s)
- C A Morehouse
- FDA Center for Devices and Radiological Health, Rockville, Maryland 20850, USA
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33
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Trock DH. Electromagnetic fields and magnets. Investigational treatment for musculoskeletal disorders. Rheum Dis Clin North Am 2000; 26:51-62, viii. [PMID: 10680193 DOI: 10.1016/s0889-857x(05)70119-8] [Citation(s) in RCA: 96] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Certain pulsed electromagnetic fields (PEMF) affect the growth of bone and cartilage in vitro, with potential application as an arthritis treatment. PEMF stimulation is already a proven remedy for delayed fractures, with potential clinical application for osteoarthritis, osteonecrosis of bone, osteoporosis, and wound healing. Static magnets may provide temporary pain relief under certain circumstances. In both cases, the available data is limited. The mechanisms underlying the use of PEMF and magnets are discussed.
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Affiliation(s)
- D H Trock
- Yale University School of Medicine, New Haven, Connecticut, USA
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Miki H, Ohmori M, Hirakawa E, Winters WD. Effects of environmental level magnetic field exposures on transcription of CMV immediate early promoter DNA in a cell-free in vitro transcription system. Bioelectromagnetics 1999; 20:519-21. [PMID: 10559773 DOI: 10.1002/(sici)1521-186x(199912)20:8<519::aid-bem6>3.0.co;2-z] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Effects of environmental levels of magnetic fields (MFs) on RNA synthesis have been investigated by using a cell-free system for in vitro transcription. Transcription reaction mixtures containing CMV immediate early promoter DNA plus HeLa cell nuclear extracts were exposed to each of three different MF field strengths, i.e., 10, 50, and 100 microT. Each MF exposed extract was paired with a simultaneous sham-exposure control. The present results show no significant differences in amounts of RNA synthesis in extracts of MF exposed compared with that in the sham controls. This finding is in contrast to results of prior studies of DNA synthesis in cell-free systems that showed MF exposure effects. The results of the present cell-free system studies suggest that the marked differences of MF exposure effects on DNA and on RNA synthesis direct attention to the complexity involved in confirming significant effects of exposures to environmental levels of MFs in biosystems in vivo and in vitro.
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Affiliation(s)
- H Miki
- Department of Pathology, Kagawa Medical University, Kagawa, Japan. mikih.ac.jp
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35
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Khadir R, Morgan JL, Murray JJ. Effects of 60 Hz magnetic field exposure on polymorphonuclear leukocyte activation. BIOCHIMICA ET BIOPHYSICA ACTA 1999; 1472:359-67. [PMID: 10572957 DOI: 10.1016/s0304-4165(99)00142-7] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
We have investigated the effects of a sinusoidal 60 Hz magnetic field on free radical (superoxide anion) production, degranulation (beta-glucuronidase and lysozyme release) and viability in human neutrophils (PMNs). Experiments were performed blindly in very controlled conditions to examine the effects of a magnetic field in resting PMNs and in PMNs stimulated with a tumor promoter: phorbol 12-myristate 13-acetate (PMA). Exposure of unstimulated human PMNs to a 60 Hz magnetic field did not affect the functions examined. In contrast, exposure of PMNs to a 22 milliTesla (mT), 60 Hz magnetic field induced significant increases in superoxide anion (O2-) production (26.5%) and in beta-glucuronidase release (53%) when the cells were incubated with a suboptimal stimulating dose of PMA. Release of lysozyme and lactate dehydrogenase was unchanged by the magnetic field, whether the cells were stimulated or not. A 60 Hz magnetic field did not have any effect on O2- generation by a cell-free system xanthine/xanthine oxidase, suggesting that a magnetic field could upregulate common cellular events (signal transduction) leading to O2- generation and beta-glucuronidase release. In conclusion, exposure of PMNs to a 22 mT, 60 Hz magnetic field potentiates the effect of PMA on O2- generation and beta-glucuronidase release. This effect could be the result of an alteration in the intracellular signaling.
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Affiliation(s)
- R Khadir
- Department of Medicine, Vanderbilt University Medical Center, Nashville, TN 37232-0111, USA
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36
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Pipkin JL, Hinson WG, Young JF, Rowland KL, Shaddock JG, Tolleson WH, Duffy PH, Casciano DA. Induction of stress proteins by electromagnetic fields in cultured HL-60 cells. Bioelectromagnetics 1999; 20:347-57. [PMID: 10453062 DOI: 10.1002/(sici)1521-186x(199909)20:6<347::aid-bem3>3.0.co;2-i] [Citation(s) in RCA: 56] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
HL-60 cells in culture were exposed for 2 h to a sinusoidal 0.1 or 1 mT (1 or 10 Gauss) magnetic field at 60 Hz and pulse labeled after exposure with radioactive isotopes by incubation by using either [(35)S]methionine, [(3)H]leucine, or [(33)P]phosphate. The radioactive labels were incorporated into cellular proteins through synthesis or phosphorylation. Proteins were extracted from electrostatically sorted nuclei, and the heat shock/stress proteins (sp) were analyzed for synthesis and phosphorylation by two-dimensional polyacrylamide gel electrophoresis. In the control cultures (no exposure to the magnetic field), sp 72c (cognate form) was faintly observed. A 0.1 mT exposure did not show sp metabolism to be different from that of the controls; however, after a 1 mT exposure of the HL-60 cells, sp 70i (inducible form) was synthesized ([(35)S]methionine incorporation). Sp 90 was not synthesized at either field level, but was phosphorylated ([(33)P]phosphate incorporation) in the 1 mT exposure. Sp 27 (isoforms a and b) was induced after a 1 mT exposure as reflected by labeling with [(3)H]leucine. These sps were not detected after a 0.1 mT exposure. After a 1 mT exposure and labeling with [(33)P], sp 27 isoforms b and c were phosphorylated whereas isoform 'a' was not observed. Sps 70i, 72c, and 90 were identified by commercial sp antibodies. Likewise, polypeptides a, b, and c were verified as sp 27 isoforms by Western blotting. Statistical evaluation of sp areas and densities, determined from fluorographs by Western-blot analysis, revealed a significant increase in sps 90 and 27a after a 1 mT magnetic field exposure. The 1 mT magnetic field interacts at the cellular level to induce a variety of sp species. Bioelectromagnetics 20:347-357, 1999. Published 1999 Wiley-Liss, Inc.
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Affiliation(s)
- J L Pipkin
- National Center for Toxicological Research, Jefferson, Arkansas 72079, USA
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37
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Burchard J, Nguyen D, Block E. Macro- and trace element concentrations in blood plasma and cerebrospinal fluid of dairy cows exposed to electric and magnetic fields. Bioelectromagnetics 1999. [DOI: 10.1002/(sici)1521-186x(199909)20:6<358::aid-bem4>3.0.co;2-b] [Citation(s) in RCA: 23] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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38
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Tipping DR, Chapman KE, Birley AJ, Anderson M. Observations on the effects of low frequency electromagnetic fields on cellular transcription inDrosophila larvae reared in field-free conditions. Bioelectromagnetics 1999. [DOI: 10.1002/(sici)1521-186x(1999)20:2<129::aid-bem8>3.0.co;2-q] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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39
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Jahreis GP, Johnson PG, Zhao YL, Hui SW. Absence of 60-Hz, 0.1-mT magnetic field-induced changes in oncogene transcription rates or levels in CEM-CM3 cells. BIOCHIMICA ET BIOPHYSICA ACTA 1998; 1443:334-42. [PMID: 9878814 DOI: 10.1016/s0167-4781(98)00238-3] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
Our objective was to assess the reproducibility of the 60-Hz magnetic field-induced, time-dependent transcription changes of c-fos, c-jun and c-myc oncogenes in CEM-CM3 cells reported by Phillips et al. (Biochim. Biophys. Acta, 1132 (1992) 140-144). Cells were exposed to a 60-Hz magnetic field (MF) at 0.1 mT (rms), generated by a pair of Helmholtz coils energized in a reinforcing (MF) mode, or to a null magnetic field when the coils were energized in a bucking (sham) mode. After MF or sham exposure for 15, 30, 60 or 120 min, nuclei and cytoplasmic RNA were extracted. Transcription rates were measured by a nuclear run-on assay, and values were normalized against either their zero-time exposure values, or against those of the c-G3PDH (housekeeping) gene at the same time points. There was no significant difference, at P=0.05, detected between MF and either sham-exposed or control cells at any time point. Transcript levels of the oncogenes were measured by Northern analysis and normalized as above. No significant difference (P=0.05) in transcript levels between MF and either sham-exposed or control cells was detected.
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Affiliation(s)
- G P Jahreis
- Membrane Biophysics Laboratory, Department of Molecular and Cellular Biophysics, Roswell Park Cancer Institute, Buffalo, NY 14263, USA
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40
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Löscher W, Liburdy RP. Animal and cellular studies on carcinogenic effects of low frequency (50/60-Hz) magnetic fields. Mutat Res 1998; 410:185-220. [PMID: 9637236 DOI: 10.1016/s1383-5742(97)00039-2] [Citation(s) in RCA: 47] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Affiliation(s)
- W Löscher
- Department of Pharmacology, Toxicology and Pharmacy, School of Veterinary Medicine, Hannover, Germany
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41
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Lagroye I, Poncy JL. The effect of 50 Hz electromagnetic fields on the formation of micronuclei in rodent cell lines exposed to gamma radiation. Int J Radiat Biol 1997; 72:249-54. [PMID: 9269318 DOI: 10.1080/095530097143473] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Low frequency electromagnetic fields (EMF) do not produce enough energy to damage DNA, in contrast to ionizing radiations. Any relationship between increased incidence of cancer and EMF must therefore be explained by a promoting effect on cellular transformation by ionizing radiation. The aim of this study was to investigate using the cytokinesis-blocked micronucleus assay a possible amplification of the genotoxic effects of ionizing radiations in cells exposed to combined static and power-frequency electromagnetic fields. Rat tracheal epithelial cell lines were first exposed in vitro to 60Co gamma rays (0, 2 and 6 Gy) and cells were then cultured for 24 h in a homogeneous sinusoidal 50 Hz magnetic field (flux density: 100 microTrms) combined with an artificial geomagnetic-like field created by the use of horizontal and vertical pairs of Helmholtz coils. Control cells were cultured in an adjacent incubator where the background EMF was about 0.1 microTrms. Under our in vitro experimental conditions, EMF appeared to have no significant direct effect on micronucleus induction in rat tracheal cell lines. However, an increased frequency of binucleated cells with micronuclei was observed in cells exposed to 6 Gy of gamma rays and EMF, compared with gamma irradiation alone. This could enhance radiation-induced genomic alterations and increase the probability of neoplastic transformation.
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Affiliation(s)
- I Lagroye
- CEA/DSV/DRR-Laboratoire de Radiotoxicologie, Bruyères-le Châtel, France
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42
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Valtersson U, Hansson Mild K, Mattsson MO. Ornithine decarboxylase activity and polyamine levels are different in Jurkat and CEM-CM3 cells after exposure to a 50 Hz magnetic field. ACTA ACUST UNITED AC 1997. [DOI: 10.1016/s0302-4598(96)05170-7] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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43
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Fiorani M, Biagiarelli B, Vetrano F, Guidi G, Dachà M, Stocchi V. In vitro effects of 50 Hz magnetic fields on oxidatively damaged rabbit red blood cells. Bioelectromagnetics 1997. [DOI: 10.1002/(sici)1521-186x(1997)18:2<125::aid-bem5>3.0.co;2-4] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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Fam WZ, Mikhail EL. Lymphoma induced in mice chronically exposed to very strong low-frequency electromagnetic field. Cancer Lett 1996; 105:257-69. [PMID: 8697452 DOI: 10.1016/0304-3835(96)04324-8] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
Three successive generations of CFW mice were exposed to a 25-mT (250,000 mG), 60-Hz electromagnetic field for prolonged periods. At the end of the exposure period, animals from both the exposed and control groups were sacrificed for tests. A complete autopsy was performed and tissue sections were taken from the main organs for histopathological examination. The results from the pathological findings in the various animals were classified under the following categories: (1) normal; (2) lymphoid hyperplasia; (3) premalignant changes; (4) early lymphoma; (5) advanced lymphoma. The three first-generation animals developed generalized lymphoid hyperplasia. In the second-generation animals, 5% developed premalignant changes, and 15.8% had lymphoid hyperplasia. In addition, 4 female mice left in the field for 418 days developed malignant lymphoma. In the third-generation animals, 58% developed premalignant changes or malignant lymphoma. An additional 30% had lymphoid hyperplasia. Statistical analysis of the data using the Mantel-Haenszel test for the difference in the prevalence of lymphoma between the exposed and control groups shows a very significant difference for the male groups (P < 0.001), the female groups (P < 0.001), and all animals combined (P < 0.001). The results suggest a cause-effect relationship between chronic exposure to very strong 60-Hz magnetic field for prolonged period and the development of malignant lymphoma in CFW mice.
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Affiliation(s)
- W Z Fam
- Department of Electrical Engineering, Technical University of Nova Scotia, Halifax, Canada
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46
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Abstract
Recent research suggests that cells respond to electromagnetic fields in the same ways as they do to other environmental stresses.
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47
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Abstract
A number of studies have shown that exposures to environmental magnetic fields (MFs) increase cellular transcription and enhance DNA synthesis. However, little is known about the basic mechanisms underlying specific biological responses to MFs. We looked directly at the effect of MFs by using a cell-free rabbit globin cDNA synthesis system. cDNA synthesis reaction mixtures were placed in each of four exposure conditions and were tested simultaneously. Condition one was the control, with no exposure during either single-strand or double-strand synthesis (M-M-). The second condition was MF exposure only during single-strand synthesis (M+M-). The third condition was exposure only during double-strand synthesis (M-M+). The fourth condition was exposure during both single-strand and double-strand synthesis (M+M+). Results showed that cDNA synthesis was affected by 5-100 microT, 60 Hz MFs. Double-strand cDNA synthesis increased with MF exposure only during double-strand synthesis reactions (M-M+), and the greatest increase of double-strand cDNA synthesis was detected when MF exposure was at 10 microT, only during double-strand synthesis. Double-strand cDNA synthesis decreased when only single-strand synthesis reactions were exposed (M+M-; 100 microT). An increase of cDNA synthesis caused increased synthesis of rabbit globin cDNA and large-sized molecules. These results suggest that exposure to MF induced structural changes of synthesized cDNA, therefore altering the amount of cDNA. Our results show that environmental MFs can significantly alter cDNA synthesis in a cell-free system.
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Affiliation(s)
- E Hirakawa
- Department of Microbiology, University of Texas Health Science Center, San Antonio, USA
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48
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49
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Lacy-Hulbert A, Wilkins RC, Hesketh TR, Metcalfe JC. Cancer risk and electromagnetic fields. Nature 1995; 375:23. [PMID: 7723838 DOI: 10.1038/375023a0] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
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50
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Korzh-Sleptsova IL, Lindström E, Mild KH, Berglund A, Lundgren E. Low frequency MFs increased inositol 1,4,5-trisphosphate levels in the Jurkat cell line. FEBS Lett 1995; 359:151-4. [PMID: 7867788 DOI: 10.1016/0014-5793(95)00031-4] [Citation(s) in RCA: 52] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
We have earlier reported that when a weak 50 Hz MF (magnetic field) was applied, the leukemic T-cell line Jurkat responded with intracellular calcium oscillations [Lindström, et al., J. Cell Physiol., 156 (1993) 395-398]. The result suggested that the MF interfered with the signal transduction, although neither target molecules nor molecular mechanisms are at present known. In this study we found that application of a MF to Jurkat cells resulted in significant increase of inositol 1,4,5-trisphosphate (IP3) levels. Chelation of intracellular calcium ions by BAPTA/AM, did not block the increase of IP3 induced by MF. This result implied that MF-induced Ca2+ oscillations were not due to direct stimulation of the Ca(2+)-dependent phospholipase C-gamma 1 (PLC-gamma 1).
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