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Gorobets O, Gorobets S, Polyakova T, Zablotskii V. Modulation of calcium signaling and metabolic pathways in endothelial cells with magnetic fields. NANOSCALE ADVANCES 2024; 6:1163-1182. [PMID: 38356636 PMCID: PMC10863714 DOI: 10.1039/d3na01065a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/29/2023] [Accepted: 01/21/2024] [Indexed: 02/16/2024]
Abstract
Calcium signaling plays a crucial role in various physiological processes, including muscle contraction, cell division, and neurotransmitter release. Dysregulation of calcium levels and signaling has been linked to a range of pathological conditions such as neurodegenerative disorders, cardiovascular disease, and cancer. Here, we propose a theoretical model that predicts the modulation of calcium ion channel activity and calcium signaling in the endothelium through the application of either a time-varying or static gradient magnetic field (MF). This modulation is achieved by exerting magnetic forces or torques on either biogenic or non-biogenic magnetic nanoparticles that are bound to endothelial cell membranes. Since calcium signaling in endothelial cells induces neuromodulation and influences blood flow control, treatment with a magnetic field shows promise for regulating neurovascular coupling and treating vascular dysfunctions associated with aging and neurodegenerative disorders. Furthermore, magnetic treatment can enable control over the decoding of Ca signals, ultimately impacting protein synthesis. The ability to modulate calcium wave frequencies using MFs and the MF-controlled decoding of Ca signaling present promising avenues for treating diseases characterized by calcium dysregulation.
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Affiliation(s)
- Oksana Gorobets
- National Technical University of Ukraine, "Igor Sikorsky Kyiv Polytechnic Institute" Ukraine
| | - Svitlana Gorobets
- National Technical University of Ukraine, "Igor Sikorsky Kyiv Polytechnic Institute" Ukraine
| | - Tatyana Polyakova
- Institute of Physics of the Czech Academy of Sciences Prague Czech Republic
| | - Vitalii Zablotskii
- Institute of Physics of the Czech Academy of Sciences Prague Czech Republic
- International Magnetobiology Frontier Research Center (iMFRC), Science Island Hefei China
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Zhang G, Liu X, Liu Y, Zhang S, Yu T, Chai X, He J, Yin D, Zhang C. The effect of magnetic fields on tumor occurrence and progression: Recent advances. PROGRESS IN BIOPHYSICS AND MOLECULAR BIOLOGY 2023; 179:38-50. [PMID: 37019340 DOI: 10.1016/j.pbiomolbio.2023.04.001] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/13/2023] [Revised: 03/14/2023] [Accepted: 04/01/2023] [Indexed: 04/05/2023]
Abstract
Malignancies are the leading human health threat worldwide. Despite rapidly developing treatments, poor prognosis and outcome are still common. Magnetic fields have shown good anti-tumoral effects both in vitro and in vivo, and represent a potential non-invasive treatment; however, the specific underlying molecular mechanisms remain unclear. We here review recent studies on magnetic fields and their effect on tumors at three different levels: organismal, cellular, and molecular. At the organismal level, magnetic fields suppress tumor angiogenesis, microcirculation, and enhance the immune response. At the cellular level, magnetic fields affect tumor cell growth and biological functions by affecting cell morphology, cell membrane structure, cell cycle, and mitochondrial function. At the molecular level, magnetic fields suppress tumors by interfering with DNA synthesis, reactive oxygen species level, second messenger molecule delivery, and orientation of epidermal growth factor receptors. At present, scientific experimental evidence is still lacking; therefore, systematic studies on the biological mechanisms involved are urgently needed for the future application of magnetic fields to tumor treatment.
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Cell viability modulation through changes of Ca2+-dependent signalling pathways. PROGRESS IN BIOPHYSICS AND MOLECULAR BIOLOGY 2016; 121:45-53. [DOI: 10.1016/j.pbiomolbio.2016.01.004] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/09/2015] [Revised: 01/01/2016] [Accepted: 01/05/2016] [Indexed: 11/22/2022]
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Golbach LA, Philippi JG, Cuppen JJ, Savelkoul HF, Verburg-van Kemenade BL. Calcium signalling in human neutrophil cell lines is not affected by low-frequency electromagnetic fields. Bioelectromagnetics 2015; 36:430-43. [DOI: 10.1002/bem.21924] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2014] [Accepted: 05/11/2015] [Indexed: 12/18/2022]
Affiliation(s)
- Lieke A. Golbach
- Cell Biology and Immunology Group; Wageningen University; The Netherlands
| | - John G.M. Philippi
- Lab of Biophysics and Wageningen NMR Centre; Wageningen University; The Netherlands
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Wei J, Sun J, Xu H, Shi L, Sun L, Zhang J. Effects of extremely low frequency electromagnetic fields on intracellular calcium transients in cardiomyocytes. Electromagn Biol Med 2014; 34:77-84. [DOI: 10.3109/15368378.2014.881744] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
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Fixler D, Yitzhaki S, Axelrod A, Zinman T, Shainberg A. Correlation of magnetic AC field on cardiac myocyte Ca(2+) transients at different magnetic DC levels. Bioelectromagnetics 2012; 33:634-40. [PMID: 22532275 DOI: 10.1002/bem.21729] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2011] [Accepted: 03/29/2012] [Indexed: 11/11/2022]
Abstract
The purpose of this study was to determine the effect of extremely low frequency and weak magnetic fields (WMF) on cardiac myocyte Ca(2+) transients, and to explore the involvement of potassium channels under the WMF effect. In addition, we aimed to find a physical explanation for the effect of WMF on cardiac myocyte Ca(2+) transients. Indo-1 loaded cells, which were exposed to a WMF at 16 Hz and 40 nT, demonstrated a 75 ± 4% reduction in cytosolic Ca(2+) transients versus control. Treatment with the K(ATP) channel blocker, glibenclamide, followed by WMF at 16 Hz exposure, blocked the reduction in cytosolic calcium transients while treatment with pinacidil, a K(ATP) channel opener, or chromanol 293B, a selective potassium channel blocker of the delayed rectifier K(+) channels, did not inhibit the effect. Based on these finding and the ion cyclotron resonance frequency theory, we further investigated the effect of WMF by changing the direct current (DC) magnetic field (B(0) ). When operating different DC magnetic fields we showed that the WMF value changed correspondingly: for B(0) = 44.5 µT, the effect was observed at 17.05 Hz; for B(0) = 46.5 µT, the effect was observed at 18.15 Hz; and for B(0) = 49 µT the effect was observed at 19.1 Hz. We can conclude that the effect of WMF on Ca(2+) transients depends on the DC magnetic field level.
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Affiliation(s)
- Dror Fixler
- Institute of Nanotechnology and Advanced Materials, Bar Ilan University, Ramat Gan, Israel.
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Snoussi S, May AE, Coquet L, Chan P, Jouenne T, Landoulsi A, Dé E. Adaptation of Salmonella enterica Hadar under static magnetic field: effects on outer membrane protein pattern. Proteome Sci 2012; 10:6. [PMID: 22304719 PMCID: PMC3292939 DOI: 10.1186/1477-5956-10-6] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2011] [Accepted: 02/03/2012] [Indexed: 12/29/2022] Open
Abstract
Background Salmonella enterica serovar Hadar (S. Hadar) is a highly prevalent foodborne pathogen and therefore a major cause of human gastroenteritis worldwide. Outer membrane proteins whose production is often regulated by environmental conditions also play important roles in the adaptability of bacterial pathogens to various environments. Results The present study investigated the adaptation of S. Hadar under the effect of acute static magnetic field exposure (200 mT, 9 h) and the impact on the outer membrane protein pattern. Via two-dimensional electrophoresis (2-DE) and LC-MS/MS spectrometry, we compared the proteome of enriched-outer membrane fraction before and after exposure to a magnetic field. A total of 11 proteins, displaying more than a two-fold change, were differentially expressed in exposed cells, among which 7 were up-regulated and 4 down-regulated. These proteins were involved in the integrity of cell envelope (TolB, Pal), in the response to oxidative stress (OmpW, dihydrolipoamide dehydrogenase, UspF), in the oxidative stress status (bacterioferritin), in virulence (OmpX, Yfgl) or in motility (FlgE and UspF). Complementary experiments associated the down-regulation of FlgE and UspF with an alteration of swarming, a flagella-driven motility, under SMF. Furthermore, the antibiotic disc diffusion method confirmed a decrease of gentamicin susceptibility in exposed cells. This decrease could be partly associated with the up-regulation of TolC, outer membrane component of an efflux pump. OmpA, a multifunctional protein, was up-regulated. Conclusions SMF (200 mT) seems to maintain the cell envelope integrity and to submit the exposed cells to an oxidative stress. Some alterations suggest an increase of the ability of exposed cells to form biofilms.
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Affiliation(s)
- Sarra Snoussi
- Laboratoire de Biochimie et Biologie Moléculaire, Faculté des Sciences de Bizerte, Université de Carthage, Zarzouna, Bizerte, Tunisie.
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Tagourti J, El May A, Aloui A, Chatti A, Ben Aissa R, Landoulsi A. Static magnetic field increases the sensitivity of Salmonella to gentamicin. ANN MICROBIOL 2010. [DOI: 10.1007/s13213-010-0081-9] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022] Open
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Zhang X, Liu X, Pan L, Lee I. Magnetic fields at extremely low-frequency (50Hz, 0.8mT) can induce the uptake of intracellular calcium levels in osteoblasts. Biochem Biophys Res Commun 2010; 396:662-6. [DOI: 10.1016/j.bbrc.2010.04.154] [Citation(s) in RCA: 50] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2010] [Accepted: 04/28/2010] [Indexed: 11/24/2022]
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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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Scarlett SS, White JA, Blackmore PF, Schoenbach KH, Kolb JF. Regulation of intracellular calcium concentration by nanosecond pulsed electric fields. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2009; 1788:1168-75. [DOI: 10.1016/j.bbamem.2009.02.006] [Citation(s) in RCA: 79] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/02/2008] [Revised: 01/14/2009] [Accepted: 02/02/2009] [Indexed: 11/16/2022]
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McCreary CR, Dixon SJ, Fraher LJ, Carson JJL, Prato FS. Real-time measurement of cytosolic free calcium concentration in Jurkat cells during ELF magnetic field exposure and evaluation of the role of cell cycle. Bioelectromagnetics 2006; 27:354-64. [PMID: 16715520 DOI: 10.1002/bem.20248] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
Extremely low frequency magnetic fields (ELF MF) have been reported to alter a number of cell signaling pathways, including those involved in proliferation, differentiation and apoptosis where cytosolic free calcium ([Ca(2+)](c)) plays an important role. To better understand the biological conditions under which ELF MF exposure might alter [Ca(2+)](c), we measured [Ca(2+)](c) by ratiometric fluorescence spectrophotometry during exposure to ELF MF in Jurkat E6.1 cells synchronized to different phases of the cell cycle. Suspensions of cells were exposed either to a near zero MF (Null) or a 60 Hz, 100 microT sinusoidal MF superimposed upon a collinear 78.1 microT static MF (AC + DC). An initial series of experiments indicated that the maximum increase in [Ca(2+)](c) above baseline after stimulation with anti-CD3 was significantly higher in samples exposed to AC + DC (n = 30) compared to Null (n = 30) with the largest difference in G2-M enriched samples. However, in a second study with G2-M enriched cells, samples treated with AC + DC (n = 17) were not statistically different from Null-treated samples (n = 27). Detailed analysis revealed that the dynamics in [Ca(2+)](c) before and after stimulation with anti-CD3 were dissimilar between Null samples from each study. From the results, we concluded (i) that the ELF MF increased [Ca(2+)](c) during an antibody-induced signaling event, (ii) that the ELF MF effect did not depend to a large degree on cell cycle, and (iii) that a field-related change in [Ca(2+)](c) signaling appeared to correlate with features in the [Ca(2+)](c) dynamics. Future work could evaluate [Ca(2+)](c) dynamics in relation to the phase of the cell cycle and inter-study variation, which may reveal factors important for the observation of real-time effects of ELF MF on [Ca(2+)](c).
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Affiliation(s)
- Cheryl R McCreary
- Imaging Program, Lawson Health Research Institute, London, Ontario, Canada
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Ikehara T, Yamaguchi H, Hosokawa K, Houchi H, Park KH, Minakuchi K, Kashimoto H, Kitamura M, Kinouchi Y, Yoshizaki K, Miyamoto H. Effects of a time-varying strong magnetic field on transient increase in Ca2+ release induced by cytosolic Ca2+ in cultured pheochromocytoma cells. Biochim Biophys Acta Gen Subj 2005; 1724:8-16. [PMID: 15890451 DOI: 10.1016/j.bbagen.2005.03.008] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2004] [Revised: 02/18/2005] [Accepted: 03/14/2005] [Indexed: 10/25/2022]
Abstract
Exposure of pheochromocytoma (PC 12) cells to a time-varying 1.51 T magnetic field inhibited an increase in the intracellular Ca2+ concentration ([Ca2+]i) induced by addition of caffeine to Ca(2+)-free medium. This inhibition occurred after a 15-min exposure and was maintained for at least 2 h. [Ca2+]i sharply increased in cells loaded with cyclic ADP-ribose, and 2-h exposure significantly suppressed the increase. Addition of ATP induced a transient increase in intracellular Ca2+ release mediated by IP3 receptor, and this increase was strongly inhibited by the exposure. Results indicated that the magnetic field exposure strongly inhibited Ca2+ release mediated by both IP3 and ryanodine receptors in PC 12 cells. However, thapsigargin-induced Ca2+ influx (capacitative Ca2+ entry) across the cell membrane was unaffected. The ATP content was maintained at the normal level during the 2-h exposure, suggesting that ATP hydrolysis was unchanged. Therefore, Mg2+ which is known to be released by ATP hydrolysis and inhibit intracellular Ca2+ release may not relate the exposure-caused inhibition. Eddy currents induced in culture medium appear to change cell membrane properties and indirectly inhibit Ca2+ release from endoplasmic reticulum and other Ca2+ stores in PC 12 cells.
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Affiliation(s)
- Toshitaka Ikehara
- Department of Physiology, Pathophysiological Preventive Medicine, Institute of Health Biosciences, The University of Tokushima Graduate School, 3-18-15 Kuramoto-cho, Tokushima 770-8503, Japan
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Roman A, Zyss T, Nalepa I. Magnetic field inhibits isolated lymphocytes' proliferative response to mitogen stimulation. Bioelectromagnetics 2005; 26:201-6. [PMID: 15768428 DOI: 10.1002/bem.20066] [Citation(s) in RCA: 6] [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
We aimed to find out how the exposure of isolated lymphocytes to a pulsed magnetic field (MF) affected their in vitro proliferative response to mitogenic stimulation. Cells were exposed to MF of various intensities (0.3, 0.6, and 1.2 T) at a constant frequency of 30 Hz, for a period of 60, 180, and 330 s. Then, the proliferative response of splenocytes was induced by optimal concentrations of concanavalin A (Con A; mitogenic toward T cells), bacterial lipopolysaccharide (LPS; mitogenic toward B cells), or pokeweed mitogen (PWM; mitogenic toward both populations). We found that the exposure of lymphocytes to the MF profoundly inhibited their proliferative response to mitogens. The suppressive action of the MF on B and T cell proliferation was intensified when a cooperative response of those two lymphocyte populations was simultaneously induced by PWM. The inhibitory effect of MF depended on the exposure time and MF intensity. Prolonged exposure and/or a stronger intensity of the MF weakened its inhibitory influence on the response of lymphocyte to mitogenic stimulation. The data show that an exposure to MF may influence the activity of lymphocytes in their response to mitogenic stimuli.
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Affiliation(s)
- Adam Roman
- Laboratory of Intracellular Signalling, Department of Biochemistry, Institute of Pharmacology, Polish Academy of Sciences, 31-343 Kraków, Poland.
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Potenza L, Ubaldi L, De Sanctis R, De Bellis R, Cucchiarini L, Dachà M. Effects of a static magnetic field on cell growth and gene expression in Escherichia coli. Mutat Res 2004; 561:53-62. [PMID: 15238230 DOI: 10.1016/j.mrgentox.2004.03.009] [Citation(s) in RCA: 76] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2003] [Revised: 03/08/2004] [Accepted: 03/19/2004] [Indexed: 10/26/2022]
Abstract
Escherichia coli cultures exposed to a 300mT static magnetic field (SMF) were studied in order to analyse possible induced changes in cellular growth and gene expression. Biomass was evaluated by visible-light spectrometry and gene expression analyses were carried out by use of RNA arbitrarily primed PCR. The bacterial strain XL-1Blue, cultivated in traditional and modified Luria-Bertani medium, was exposed to SMF generated by permanent neodymium magnetic disks. The results show alterations induced by SMF in terms of increased cell proliferation and changes in gene expression compared with control groups. Three cDNAs were found to be expressed only in the exposed cells, whereas one cDNA was more expressed in the controls. One clone, expressed only in the exposed cells, corresponds to a putative transposase. This is of particular interest in that it suggests that exposure to a magnetic field may stimulate transposition activity.
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Affiliation(s)
- Lucia Potenza
- Giorgio Fornaini Institute of Biological Chemistry, University of Urbino Carlo Bo, 61029 Urbino, PU, Italy.
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Madec F, Billaudel B, Charlet de Sauvage R, Sartor P, Veyret B. Effects of ELF and static magnetic fields on calcium oscillations in islets of Langerhans. Bioelectrochemistry 2003; 60:73-80. [PMID: 12893312 DOI: 10.1016/s1567-5394(03)00049-5] [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: 11/17/2022]
Abstract
Several experimental studies have produced contradictory results on the effects of extremely low frequency (ELF) magnetic fields on cellular processes involving calcium ions. Furthermore, the few positive results have not been independently replicated. In most of these studies, isolated cells were used. Our study used mouse islets of Langerhans, in which very regular oscillations of calcium concentration can be observed at length. These oscillations are sustained by processes that imply energetic and inter-intracellular communication. Various magnetic fields were applied, either sinusoidal at different frequencies (50 Hz or multiples of the natural oscillation frequency) at 0.1 or 1 mT or static at 1 mT. Islets were also exposed to "cyclotron resonance" conditions. There was neither alteration of the fundamental oscillation frequency nor the degree of organisation under all exposure conditions. Using this sensitive model, we could not show new evidence of alterations of calcium processes under exposure to various magnetic fields.
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Affiliation(s)
- F Madec
- PIOM Laboratory, ENSCPB, University of Bordeaux 1, 16 Pey Berland Avenue, 33607 Cedex, Pessac, France
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Craviso GL, Poss J, Lanctot C, Lundback SS, Chatterjee I, Publicover NG. Intracellular calcium activity in isolated bovine adrenal chromaffin cells in the presence and absence of 60 Hz magnetic fields. Bioelectromagnetics 2002; 23:557-67. [PMID: 12395410 DOI: 10.1002/bem.10045] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
This study examined whether 60 Hz magnetic field (MF) exposure alters intracellular calcium levels ([Ca(2+)](i)) in isolated bovine adrenal chromaffin cells, a classic model of neural responses. [Ca(2+)](i) was monitored by fluorescence video imaging of cells loaded with the calcium indicator fluo-4 during exposures to magnetic flux densities of 0.01, 0.1, 1.0, 1.4, or 2.0 mT. MFs generated by Helmholtz coils constructed from bifilar wire allowed both 60 Hz field and sham exposures. Following a 5 min monitoring period to establish baseline patterns, cells were subjected for 10 min to a 60 Hz MF, sham field or no field. Reference calcium responses and assessment of cell excitability were obtained by the sequential addition of the nicotinic cholinergic receptor agonist dimethylphenylpiperazinium (DMPP) and a depolarizing concentration of KCl. Throughout an 8 day culture period, cells exhibited spontaneous fluctuations in [Ca(2+)](i). Comparisons of the number of cells exhibiting transients, the number and types of calcium transients, as well as the time during monitoring when transients occurred showed no significant differences between MF exposed cells and either sham exposed or nonexposed cells. With respect to the percentage of cells responding to DMPP, differences between 1 and 2 mT exposed cells and both nonexposed and sham exposed cells reached statistical significance during the first day in culture. No statistically significant differences were observed for responses to KCl. In summary, our data indicate that [Ca(2+)](i) in chromaffin cells is unaffected by the specific 60 Hz MF intensities used in this study. On the other hand, plasma membrane nicotinic receptors may be affected in a manner that is important for ligand-receptor interactions.
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Affiliation(s)
- Gale L Craviso
- Department of Pharmacology, University of Nevada, Reno, Nevada 89557, USA.
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Testorf MF, Ake Oberg P, Iwasaka M, Ueno S. Melanophore aggregation in strong static magnetic fields. Bioelectromagnetics 2002; 23:444-9. [PMID: 12210562 DOI: 10.1002/bem.10040] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Contradicting results can be found in the literature on effects from magnetic exposure to pigment cells. We have studied the influence of strong, static, homogenous magnetic fields of 8 and 14 T on melanophore aggregation during exposure to the field. Melanophores, black pigment cells, in fish are large flat cells having intracellular black pigment granules. Due to large size, high optical contrast, and quick response to drugs, melanophores are attractive as biosensors as well as for model studies of intracellular processes. This is especially true for modeling nerve cells, since melanophores share stem cells with axons. Twenty experiments on black tetra fish fins were carried out in the two magnetic flux densities. The same number of control experiments were carried out in the magnet with the magnetic field turned off. Several factors, such as the degree of maximal aggregation, speed of aggregation, and irregularity of the speed, were examined. The statistical analysis showed no significant field effects on the aggregation, with one exception: the irregularity in aggregation speed in the 8 T field, compared to control. The believed reorientation of the cytoskeleton (microtubules) in the field or the induced Lorentz force on moving pigment granules, did not affect the aggregation.
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Affiliation(s)
- Martin F Testorf
- Department of Biomedical Engineering, Linköping University, Linköping, Sweden.
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Obo M, Konishi S, Otaka Y, Kitamura S. Effect of magnetic field exposure on calcium channel currents using patch clamp technique. Bioelectromagnetics 2002; 23:306-14. [PMID: 11948611 DOI: 10.1002/bem.10022] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Calcium influxes through the membrane of PC-12D cells were measured under exposure to DC biased AC magnetic fields in resonant conditions of the ion cyclotron and the ion parametric resonance hypotheses and compared with influxes in cells without exposure to the magnetic field. After cancellation of the geomagnetic field, the cells were exposed to the horizontal fields generated by a current sheet, a planar sheet of conductor which generated a satisfactorily homogeneous horizontal magnetic field on the stage of a microscope without hindering treatment of a cell under observation. At or near any resonant conditions, no change in calcium influx could be detected under standard patch clamp conditions.
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Affiliation(s)
- Mayumi Obo
- Mitsubishi Chemical Safety Institute, Ibaraki, Japan.
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McCreary CR, Thomas AW, Prato FS. Factors confounding cytosolic calcium measurements in Jurkat E6.1 cells during exposure to ELF magnetic fields. Bioelectromagnetics 2002; 23:315-28. [PMID: 11948612 DOI: 10.1002/bem.10019] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
Reported changes in the cytosolic calcium concentration ([Ca2+](c)) as a result of exposure to extremely low frequency (ELF) magnetic fields (MF) have been equivocal. In this study, we examine the possibility that some of these differences are attributable to variability associated with the cell cycle, pH of the suspension medium, and response to a calcium agonist. We used a custom designed spectrofluorimeter to measure [Ca2+](c) in Indo 1-AM loaded Jurkat E6.1 cells suspended in conditioned RPMI 1640 medium containing 10% fetal bovine serum. Four exposures were examined: zero static MF (Null), 60 Hz 100 microT(peak) sinusoidal MF (AC), 78 microT static MF (DC), and the combination of the 60 Hz and the 78 microT static MF (AD + DC). A significant decrease in normalized [Ca2+](c) values between 375-495 s for the DC and AC + DC groups was found in comparison to the Null group. However, statistical analysis indicated that cell cycle and quality of the alpha-CD3 monoclonal antibody response were significant covariates, while pH was not a significant covariate. When the effect of these covariates was taken into account, all exposure groups were significantly different from the control. Our results suggest that ELF MF effects may not be seen unless correction is made for biological variability of each cell preparation with respect to cell cycle and [Ca2+](c) response to antigen stimulation.
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Affiliation(s)
- Cheryl R McCreary
- Imaging Division Lawson, Health Research Institute, London, Ontario, Canada.
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Boland A, Delapierre D, Mossay D, Dresse A, Seutin V. Effect of intermittent and continuous exposure to electromagnetic fields on cultured hippocampal cells. Bioelectromagnetics 2002; 23:97-105. [PMID: 11835256 DOI: 10.1002/bem.102] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
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.
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Affiliation(s)
- A Boland
- Laboratory of Pharmacology, Institute of Pathology B23a, University of Liège, Liège, Belgium.
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23
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Hillert L, Flato S, Georgellis A, Arnetz BB, Kolmodin-Hedman B. Environmental illness: fatigue and cholinesterase activity in patients reporting hypersensitivity to electricity. ENVIRONMENTAL RESEARCH 2001; 85:200-206. [PMID: 11237508 DOI: 10.1006/enrs.2000.4225] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
The lack of a pathophysiological marker hinders studies on environmental illnesses of unknown origin. Hence, research focused on the identification of such a marker is a priority. This study investigated the nature and a possible etiology of fatigue in hypersensitivity to electricity (the most commonly reported environmental illness in Sweden). The aim was to test the hypothesis that perceived fatigue was due to alterations in cholinesterase activity. The study group consisted of 14 people who reported a hypersensitivity to electricity, including disabling fatigue. We assessed cholinesterase activity three times: twice based on current symptoms reported by the subjects (severe fatigue attributed to electromagnetic fields and absence of this symptom) and once at a randomly selected time. No significant reduction in acetylcholinesterase was identified in any subject. Examined on a group level, no significant reduction in activity was identified at the time of severe fatigue, and no correlation between reported degree of fatigue and cholinesterase activity was observed. Fatigue attributed to electromagnetic fields was nonphysical and showed a significant correlation to difficulties in concentrating. The results do not support the hypothesis that a change in cholinesterase activity mediates fatigue in people reporting hypersensitivity to electricity.
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Affiliation(s)
- L Hillert
- Department of Environmental Health, Karolinska Institutet, Stockholm, Sweden
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24
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Lindström E, Still M, Mattsson MO, Mild KH, Luben RA. ELF magnetic fields initiate protein tyrosine phosphorylation of the T cell receptor complex. Bioelectrochemistry 2001; 53:73-8. [PMID: 11206927 DOI: 10.1016/s0302-4598(00)00125-2] [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: 11/21/2022]
Abstract
The human T cell line Jurkat registers a sinusoidal extremely low frequency (ELF), 0.10 mT magnetic fields (MFs) at the level of the plasma membrane. In this study, the protein tyrosine phosphorylation (PY) of two membrane-associated proteins in Jurkat cells were examined following a short-term MFs exposure, the zeta chains and the Src kinases p56lck. These proteins are interesting to study since the earliest biochemical event upon T cell receptor (TcR) activation is PY of the zeta chains. These signalling chains in the TcR complex was assessed using Western blotting and the activation of the p56lck kinase was analysed by in vitro kinase assay. The MFs exposure of Jurkat for 5 min activated p56lck and resulted in PY of zeta. These findings are in line with earlier reports on how MFs exposure affects signal transduction in Jurkat.
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Affiliation(s)
- E Lindström
- National Institute for Working Life, Umeå, Sweden.
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25
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Cook LL, Persinger MA, Koren SA. Differential effects of low frequency, low intensity (<6 mG) nocturnal magnetic fields upon infiltration of mononuclear cells and numbers of mast cells in Lewis rat brains. Toxicol Lett 2000; 118:9-19. [PMID: 11137304 DOI: 10.1016/s0378-4274(00)00259-9] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
Abstract
Immediately after inoculation to induce experimental allergic encephalomyelitis, 64 female Lewis rats were exposed to either a reference condition (<10 nT) or to one of two frequencies (7 Hz, 40 Hz) of magnetic fields whose two intensities (either 50 nT or 500 nT) were amplitude-modulated for 6 min once per hour between midnight and 8 h for 15 nights. Rats that had been exposed to the 7 Hz, low intensity fields displayed fewer numbers of foci of infiltrations of mononuclear cells compared to all other groups that did not differ significantly from each other. Rats exposed to the 5 mG (500 nT), 40 Hz magnetic fields displayed more foci in the right thalamus while those exposed to the 5 mG, 7 Hz fields displayed more foci in the left thalamus. Numbers of mast cells within the thalamus were also affected by the treatments. These results suggest that weak magnetic fields can affect the infiltration of immunologically responsive cells and the presence of mast cells in brain parenchyma. Implications for the potential etiology of 'electromagnetic sensitivity' symptoms are discussed.
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Affiliation(s)
- L L Cook
- Behavioral Neuroscience Laboratory, Department of Biology, Laurentian University, Sudbury, Ontario, Canada P3E 2C6
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26
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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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