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Worel N, Mišík M, Kundi M, Ferk F, Hutter HP, Nersesyan A, Wultsch G, Krupitza G, Knasmueller S. Impact of high (1950 MHz) and extremely low (50 Hz) frequency electromagnetic fields on DNA damage caused by occupationally relevant exposures in human derived cell lines. Toxicol In Vitro 2024; 100:105902. [PMID: 39025159 DOI: 10.1016/j.tiv.2024.105902] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2024] [Revised: 06/27/2024] [Accepted: 07/15/2024] [Indexed: 07/20/2024]
Abstract
Epidemiological studies indicate that electromagnetic fields (EMF) are associated with cancer in humans. Exposure to mobile phone specific high frequency fields (HF-EMF) may lead to increased glioma risks, while low frequency radiation (LF-EMF) is associated with childhood leukemia. We studied the impact of HF-EMF (1950 MHz, UMTS signal) on DNA stability in an astrocytoma cell line (1321N1), and the effect of LF-EMF (50 Hz) in human derived lymphoma (Jurkat) cells. To find out if these fields affect chemically induced DNA damage, co-exposure experiments were performed. The cells were exposed to HF-EMF or LF-EMF and treated simultaneously and sequentially with mutagens. The compounds cause DNA damage via different molecular mechanisms, i.e. pyrimidine dimers which are characteristic for UV light (4-nitroquinoline 1-oxide, 4NQO), bulky base adducts (benzo[a]pyrene diolepoxide, BPDE), DNA-DNA and DNA-protein cross links and oxidative damage (NiCl2, CrO3). DNA damage was measured in single cell gel electrophoresis (comet) assays. We found a moderate reduction of basal and 4NQO-induced DNA damage in the astrocytoma line, but no significant alterations of chemically induced DNA migration by the HF and LF fields under all other experimental series. The biological consequences of the moderate reduction remain unclear, but our findings indicate that acute mobile phone and power line specific EMF exposures do not enhance genotoxic effects caused by occupationally relevant chemical exposures.
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Affiliation(s)
- Nadine Worel
- Center for Cancer Research, Medical University of Vienna, Borschkegasse 8a, A 1090 Vienna, Austria
| | - Miroslav Mišík
- Center for Cancer Research, Medical University of Vienna, Borschkegasse 8a, A 1090 Vienna, Austria
| | - Michael Kundi
- Center for Public Health, Department of Environmental Health, Medical University of Vienna, Vienna, Austria
| | - Franziska Ferk
- Center for Cancer Research, Medical University of Vienna, Borschkegasse 8a, A 1090 Vienna, Austria
| | - Hans-Peter Hutter
- Center for Public Health, Department of Environmental Health, Medical University of Vienna, Vienna, Austria
| | - Armen Nersesyan
- Center for Cancer Research, Medical University of Vienna, Borschkegasse 8a, A 1090 Vienna, Austria
| | | | - Georg Krupitza
- Department of Pathology, Medical University of Vienna, A-1090 Vienna, Austria
| | - Siegfried Knasmueller
- Center for Cancer Research, Medical University of Vienna, Borschkegasse 8a, A 1090 Vienna, Austria.
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2
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Nguyen H, Segers S, Ledent M, Anthonissen R, Verschaeve L, Hinsenkamp M, Collard JF, Feipel V, Mertens B. Effects of long-term exposure to 50 Hz magnetic fields on cell viability, genetic damage, and sensitivity to mutagen-induced damage. Heliyon 2023; 9:e14097. [PMID: 36923833 PMCID: PMC10008985 DOI: 10.1016/j.heliyon.2023.e14097] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2022] [Revised: 02/14/2023] [Accepted: 02/21/2023] [Indexed: 03/02/2023] Open
Abstract
Until today, it remains controversial whether long-term exposure to extremely low-frequency magnetic fields (ELF-MF) below the legislative exposure limits could result in adverse human health effects. In the present study, the effects of long-term in vitro MF exposure on three different study endpoints (cell viability, genetic damage, and sensitivity to damage induced by known mutagens) were investigated in the human B lymphoblastoid (TK6) cell line. Cells were exposed to 50 Hz MF at three selected magnetic flux densities (i.e., 10, 100, and 500 μT) for different exposure periods ranging from 96h up to 6 weeks. Cell viability following MF exposure was assessed using the ATP-based cell viability assay. Effects of MF exposure on cell genetic damage and cell sensitivity to mutagen-induced damage were evaluated using the in vitro alkaline comet assay and the in vitro cytokinesis block micronucleus assay. The results showed that long-term exposure up to 96h to 50 Hz MF at all tested flux densities could significantly increase TK6 cell viability. In contrast, long-term MF exposure did not affect cell genetic damage, and long-term pre-exposure to MF did not change cell sensitivity to damage induced by known mutagens. At certain time points, statistically significant difference in genotoxicity test results were observed between the MF-exposed cells and the control cells. However, these observations could not be confirmed in the repeat experiments, indicating that they are probably not biologically significant.
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Affiliation(s)
- Ha Nguyen
- Scientific Direction Chemical and Physical Health Risks, Sciensano, 1050 Ixelles, Belgium.,Faculty of Medicine, Universite Libre de Bruxelles, 1070 Brussels, Belgium
| | - Seppe Segers
- Scientific Direction Chemical and Physical Health Risks, Sciensano, 1050 Ixelles, Belgium
| | - Maryse Ledent
- Scientific Direction Chemical and Physical Health Risks, Sciensano, 1050 Ixelles, Belgium
| | - Roel Anthonissen
- Scientific Direction Chemical and Physical Health Risks, Sciensano, 1050 Ixelles, Belgium
| | - Luc Verschaeve
- Scientific Direction Chemical and Physical Health Risks, Sciensano, 1050 Ixelles, Belgium
| | - Maurice Hinsenkamp
- Faculty of Medicine, Universite Libre de Bruxelles, 1070 Brussels, Belgium
| | | | - Veronique Feipel
- Faculty of Medicine, Universite Libre de Bruxelles, 1070 Brussels, Belgium
| | - Birgit Mertens
- Scientific Direction Chemical and Physical Health Risks, Sciensano, 1050 Ixelles, Belgium
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López-Díaz B, Mercado-Sáenz S, Burgos-Molina AM, González-Vidal A, Sendra-Portero F, Ruiz-Gómez MJ. Genomic DNA damage induced by co-exposure to DNA damaging agents and pulsed magnetic field. Int J Radiat Biol 2022; 99:853-865. [PMID: 36069754 DOI: 10.1080/09553002.2022.2121873] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/14/2022]
Abstract
PURPOSE Many articles describe the effects of extremely low-frequency magnetic fields (MF) on DNA damage induction. However, the mechanism of MF interaction with living matter is not yet known with certainty. Some works suggest that MF could induce an increase in the efficacy of Reactive Oxygen Species (ROS) production. This work investigates whether pulsed MF exposure produces alterations in genomic DNA damage induced by co-exposure to DNA damaging agents (bleomycin and methyl methanesulfonate (MMS)). MATERIALS AND METHODS Genomic DNA, prepared from S. cerevisiae cultures, was exposed to pulsed MF (1.5 mT peak, 25 Hz) and MMS (0-1%) (15-60 minutes), and to MF and bleomycin (0-0.6 IU/ml) (24-72 hours). The damage induced to DNA was evaluated by electrophoresis and image analysis. RESULTS Pulsed MF induced an increment in the level of DNA damage produced by MMS and bleomycin in all groups at the exposure conditions assayed. CONCLUSIONS Pulsed MF could modulate the cytotoxic action of MMS and bleomycin. The observed effect could be the result of a multifactorial process influenced by the type of agent that damages DNA, the dose, and the duration of the exposure to the pulsed MF.
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Affiliation(s)
- Beatriz López-Díaz
- Departamento de Radiología y Medicina Física, Facultad de Medicina, Universidad de Málaga, Málaga, España
| | - Silvia Mercado-Sáenz
- Departamento de Radiología y Medicina Física, Facultad de Medicina, Universidad de Málaga, Málaga, España
| | - Antonio M Burgos-Molina
- Departamento de Radiología y Medicina Física, Facultad de Medicina, Universidad de Málaga, Málaga, España
| | - Alejandro González-Vidal
- Departamento de Radiología y Medicina Física, Facultad de Medicina, Universidad de Málaga, Málaga, España
| | - Francisco Sendra-Portero
- Departamento de Radiología y Medicina Física, Facultad de Medicina, Universidad de Málaga, Málaga, España
| | - Miguel J Ruiz-Gómez
- Departamento de Radiología y Medicina Física, Facultad de Medicina, Universidad de Málaga, Málaga, España
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Сhiral and Racemic Fields Concept for Understanding of the Homochirality Origin, Asymmetric Catalysis, Chiral Superstructure Formation from Achiral Molecules, and B-Z DNA Conformational Transition. Symmetry (Basel) 2019. [DOI: 10.3390/sym11050649] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
The four most important and well-studied phenomena of mirror symmetry breaking of molecules were analyzed for the first time in terms of available common features and regularities. Mirror symmetry breaking of the primary origin of biological homochirality requires the involvement of an external chiral inductor (environmental chirality). All reviewed mirror symmetry breaking phenomena were considered from that standpoint. A concept of chiral and racemic fields was highly helpful in this analysis. A chiral gravitational field in combination with a static magnetic field (Earth’s environmental conditions) may be regarded as a hypothetical long-term chiral inductor. Experimental evidences suggest a possible effect of the environmental chiral inductor as a chiral trigger on the mirror symmetry breaking effect. Also, this effect explains a conformational transition of the right-handed double DNA helix to the left-handed double DNA helix (B-Z DNA transition) as possible DNA damage.
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5
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Kakikawa M, Maeda T, Yamada S. Combined Effect of 60 Hz Magnetic Fields and Anticancer Drugs on Human Hepatoma HepG2 Cells. ACTA ACUST UNITED AC 2019. [DOI: 10.1109/jerm.2018.2880341] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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6
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Effects of electromagnetic field, cisplatin and morphine on cytotoxicity and expression levels of DNA repair genes. Mol Biol Rep 2018; 45:807-814. [PMID: 29968116 DOI: 10.1007/s11033-018-4223-7] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2018] [Accepted: 06/24/2018] [Indexed: 12/18/2022]
Abstract
Morphine (Mor) is widely used as an analgesic drug in cancers and in combination with chemotherapy is known to have DNA damaging effects on non-targeted cell. This study surveyed the effect of Mor in combination with 50-Hz electromagnetic field (EMF) and co-treatment of cisplatin in combination with Mor and EMF on the expression of genes involved in DNA repair pathways. MCF-7 and SH-SY5Y cells were treated with 5.0 µM Mor and then exposed to 50-Hz 0.50 mT EMF in the intermittent pattern of 15 min field-on/15 min field-off. Gene expression, cisplatin and bleomycin cytotoxicity were measured using real-time PCR and MTT assay. Mor treated cells showed significant down-regulation of the examined genes, while in "Mor + EMF" treatments the genes were not significantly changed. IC50 of cisplatin was significantly elevated in both cell lines when co-treated with "Mor + EMF" compared with Mor treated cells. Non-homologous end joining (NHEJ) related genes were significantly decreased in co-treatment of cisplatin and "Mor + EMF" which led to bleomycin higher cytotoxicity in SH-SY5Y not in MCF-7. Our data is promising for providing a cell line-specific sensitization by combination of cisplatin and "Mor + EMF" treatment with local administration of double strand breaking agents.
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7
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Villarini M, Gambelunghe A, Giustarini D, Ambrosini MV, Fatigoni C, Rossi R, Dominici L, Levorato S, Muzi G, Piobbico D, Mariucci G. No evidence of DNA damage by co-exposure to extremely low frequency magnetic fields and aluminum on neuroblastoma cell lines. Mutat Res 2017; 823:11-21. [PMID: 28985943 DOI: 10.1016/j.mrgentox.2017.09.001] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2017] [Revised: 07/28/2017] [Accepted: 09/01/2017] [Indexed: 01/30/2023]
Abstract
Whether exposure to 50-60Hz extremely low frequency magnetic fields (ELF-MF) exerts neurotoxic effects is a debated issue. Analogously, the potential role of Aluminum (Al) in neurodegeneration is a matter of controversial debate. As all living organisms are exposed to ELF-MF and/or Al daily, we found investigating the early effects of co-exposure to ELF-MF and Al in SH-SY5Y and SK-N-BE-2 human neuroblastoma (NB) cells intriguing. SH-SY5Y5 and SK-N-BE-2 cells underwent exposure to 50Hz ELF-MF (0.01, 0.1 or 1mT) or AlCl3 (4 or 40μM) or co-exposure to 50Hz ELF-MF and AlCl3 for 1h continuously or 5h intermittently. The effects of the treatment were evaluated in terms of DNA damage, redox status changes and Hsp70 expression. The DNA damage was assessed by Comet assay; the cellular redox status was investigated by measuring the amount of reduced glutathione (GSH) and glutathione disulfide (GSSG) while the inducible Hsp70 expression was evaluated by western blot analysis and real-time RT-PCR. Neither exposure to ELF-MF or AlCl3 alone induced DNA damage, changes in GSH/GSSG ratio or variations in Hsp70 expression with respect to the controls in both NB cell lines. Similarly, co-exposure to ELF-MF and AlCl3 did not have any synergic toxic effects. The results of this in vitro study, which deals with the effects of co-exposure to 50Hz MF and Aluminum, seem to exclude that short-term exposure to ELF-MF in combination with Al can have harmful effects on human SH-SY5Y and SK-N-BE-2 cells.
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Affiliation(s)
- Milena Villarini
- Department of Pharmaceutical Sciences, University of Perugia, 06122 Perugia, Italy
| | | | - Daniela Giustarini
- Department of Life Sciences, Laboratory of Pharmacology and Toxicology, University of Siena, 53100 Siena, Italy
| | | | - Cristina Fatigoni
- Department of Pharmaceutical Sciences, University of Perugia, 06122 Perugia, Italy
| | - Ranieri Rossi
- Department of Life Sciences, Laboratory of Pharmacology and Toxicology, University of Siena, 53100 Siena, Italy
| | - Luca Dominici
- Department of Pharmaceutical Sciences, University of Perugia, 06122 Perugia, Italy
| | - Sara Levorato
- Department of Pharmaceutical Sciences, University of Perugia, 06122 Perugia, Italy
| | - Giacomo Muzi
- Department of Medicine, University of Perugia, 06132 Perugia, Italy
| | - Danilo Piobbico
- Department of Experimental Medicine, University of Perugia, 06132 Perugia, Italy
| | - Giuseppina Mariucci
- Department of Pharmaceutical Sciences, University of Perugia, 06122 Perugia, Italy.
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8
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Calcabrini C, Mancini U, De Bellis R, Diaz AR, Martinelli M, Cucchiarini L, Sestili P, Stocchi V, Potenza L. Effect of extremely low-frequency electromagnetic fields on antioxidant activity in the human keratinocyte cell line NCTC 2544. Biotechnol Appl Biochem 2016; 64:415-422. [PMID: 27001710 DOI: 10.1002/bab.1495] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2015] [Accepted: 03/15/2016] [Indexed: 11/09/2022]
Abstract
Some epidemiological studies have suggested possible associations between exposure to extremely low-frequency electromagnetic fields (ELF-EMFs) and various diseases. Recently, ELF-EMF has been considered as a therapeutic agent. To support ELF-EMF use in regenerative medicine, in particular in the treatment of skin injuries, we investigated whether significant cell damage occurs after ELF-EMF exposure. Reactive oxygen species (ROS) production was evaluated in the human keratinocyte exposed for 1 H to 50 Hz ELF-EMF in a range of field strengths from 0.25 to 2 G. Significant ROS increases resulted at 0.5 and 1 G and under these flux densities ROS production, glutathione content, antioxidant defense activity, and lipid peroxidation markers were assessed for different lengths of time. Analyzed parameters of antioxidant defense and membrane integrity showed a different trend at two selected magnetic fluxes, with a greater sensitivity of the cells exposed to 0.5 G, especially after 1 H. All significant alterations observed in the first 4 H of exposure reverted to controls 24 H after suggesting that under these conditions, ELF-EMF induces a slight oxidative stress that does not overwhelm the metabolic capacity of the cells or have a cytotoxic effect.
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Affiliation(s)
- Cinzia Calcabrini
- Department of Biomolecular Sciences, University of Urbino Carlo Bo, Urbino, Italy
| | - Umberto Mancini
- Department of Biomolecular Sciences, University of Urbino Carlo Bo, Urbino, Italy
| | - Roberta De Bellis
- Department of Biomolecular Sciences, University of Urbino Carlo Bo, Urbino, Italy
| | - Anna Rita Diaz
- Department of Biomolecular Sciences, University of Urbino Carlo Bo, Urbino, Italy
| | - Maddalena Martinelli
- Department of Biomolecular Sciences, University of Urbino Carlo Bo, Urbino, Italy
| | - Luigi Cucchiarini
- Department of Biomolecular Sciences, University of Urbino Carlo Bo, Urbino, Italy
| | - Piero Sestili
- Department of Biomolecular Sciences, University of Urbino Carlo Bo, Urbino, Italy
| | - Vilberto Stocchi
- Department of Biomolecular Sciences, University of Urbino Carlo Bo, Urbino, Italy
| | - Lucia Potenza
- Department of Biomolecular Sciences, University of Urbino Carlo Bo, Urbino, Italy
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9
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Zhu K, Lv Y, Cheng Q, Hua J, Zeng Q. Extremely Low Frequency Magnetic Fields Do Not Induce DNA Damage in Human Lens Epithelial Cells In Vitro. Anat Rec (Hoboken) 2016; 299:688-97. [PMID: 27079842 DOI: 10.1002/ar.23312] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2015] [Revised: 10/30/2015] [Accepted: 11/26/2015] [Indexed: 11/10/2022]
Abstract
Non-ionizing radiations, e.g., radiofrequency electromagnetic fields, could induce DNA damage and oxidative stress in human lens epithelial cells (LECs) which can be early events in cataractogenesis. Extremely low frequency magnetic fields (ELF MF) as another common form of man-made electromagnetic fields has been considered as suspected human carcinogen by International Agency for Research on Cancer (IARC) and become a focus that people play more and more attentions to. This study aimed to determine whether ELF MF can induce DNA damage in cultured human LECs at a relatively low intensity. Human LECs were exposed or sham-exposed to a 50 Hz ELF MF which produced by a well-designed exposure system at the intensity of 0.4 mT. DNA damage in human LECs was examined by the phosphorylated form of histone variant H2AX (γH2AX) foci formation assay and further explored with western blot, flow cytometry, and alkaline comet assay. Immunofluorescence analysis showed that 0.4 mT ELF MF did not significantly increase γH2AX foci formation in human LECs after 2, 6, 12, 24, or 48 hr exposure. No significant differences had been detected in γH2AX expression level between the ELF MF- and sham-exposure groups, while no obvious chromosomal DNA fragmentation was detected by alkaline comet assay after ELF MF exposure. The results indicate an absence of genotoxicity in ELF MF-exposed human epithelial cells and do not support the hypothesis that environmental ELF MF might be causally led to genomic instability via chromosomal damage response processes. Neither short nor long term continuous exposure to 50 Hz ELF MF at 0.4 mT could induce DNA damage in human lens epithelial cells in vitro.
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Affiliation(s)
- Kan Zhu
- Bioelectromagnetics Laboratory, Zhejiang University School of Medicine, Hangzhou, China
| | - Ye Lv
- Department of environmental and occupational health, Hangzhou Center for Disease Control and Prevention, Hangzhou, China
| | - Qian Cheng
- Bioelectromagnetics Laboratory, Zhejiang University School of Medicine, Hangzhou, China.,Department of health monitoring, Haining Center for Disease Control and Prevention, Haining, China
| | - Jianing Hua
- Bioelectromagnetics Laboratory, Zhejiang University School of Medicine, Hangzhou, China
| | - Qunli Zeng
- Bioelectromagnetics Laboratory, Zhejiang University School of Medicine, Hangzhou, China
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10
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Lee W, Yang KL. Using medaka embryos as a model system to study biological effects of the electromagnetic fields on development and behavior. ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY 2014; 108:187-194. [PMID: 25084399 DOI: 10.1016/j.ecoenv.2014.06.035] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/10/2014] [Revised: 06/27/2014] [Accepted: 06/28/2014] [Indexed: 06/03/2023]
Abstract
The electromagnetic fields (EMFs) of anthropogenic origin are ubiquitous in our environments. The health hazard of extremely low frequency and radiofrequency EMFs has been investigated for decades, but evidence remains inconclusive, and animal studies are urgently needed to resolve the controversies regarding developmental toxicity of EMFs. Furthermore, as undersea cables and technological devices are increasingly used, the lack of information regarding the health risk of EMFs to aquatic organisms needs to be addressed. Medaka embryos (Oryzias latipes) have been a useful tool to study developmental toxicity in vivo due to their optical transparency. Here we explored the feasibility of using medaka embryos as a model system to study biological effects of EMFs on development. We also used a white preference test to investigate behavioral consequences of the EMF developmental toxicity. Newly fertilized embryos were randomly assigned to four groups that were exposed to an EMF with 3.2kHz at the intensity of 0.12, 15, 25, or 60µT. The group exposed to the background 0.12µT served as the control. The embryos were exposed continually until hatch. They were observed daily, and the images were recorded for analysis of several developmental endpoints. Four days after hatching, the hatchlings were tested with the white preference test for their anxiety-like behavior. The results showed that embryos exposed to all three levels of the EMF developed significantly faster. The endpoints affected included the number of somites, eye width and length, eye pigmentation density, midbrain width, head growth, and the day to hatch. In addition, the group exposed to the EMF at 60µT exhibited significantly higher levels of anxiety-like behavior than the other groups did. In conclusion, the EMF tested in this study accelerated embryonic development and heightened anxiety-like behavior. Our results also demonstrate that the medaka embryo is a sensitive and cost-efficient in vivo model system to study developmental toxicity of EMFs.
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Affiliation(s)
- Wenjau Lee
- Department of Bioscience Technology, Chang Jung Christian University, No. 1, Changda Rd., Gueiren District, Tainan City, Taiwan.
| | - Kun-Lin Yang
- Department of Bioscience Technology, Chang Jung Christian University, No. 1, Changda Rd., Gueiren District, Tainan City, Taiwan
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11
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Jin YB, Choi SH, Lee JS, Kim JK, Lee JW, Hong SC, Myung SH, Lee YS. Absence of DNA damage after 60-Hz electromagnetic field exposure combined with ionizing radiation, hydrogen peroxide, or c-Myc overexpression. RADIATION AND ENVIRONMENTAL BIOPHYSICS 2014; 53:93-101. [PMID: 24305851 DOI: 10.1007/s00411-013-0506-5] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/31/2013] [Accepted: 11/25/2013] [Indexed: 06/02/2023]
Abstract
The principal objective of this study was to assess the DNA damage in a normal cell line system after exposure to 60 Hz of extremely low frequency magnetic field (ELF-MF) and particularly in combination with various external factors, via comet assays. NIH3T3 mouse fibroblast cells, WI-38 human lung fibroblast cells, L132 human lung epithelial cells, and MCF10A human mammary gland epithelial cells were exposed for 4 or 16 h to a 60-Hz, 1 mT uniform magnetic field in the presence or absence of ionizing radiation (IR, 1 Gy), H(2)O(2) (50 μM), or c-Myc oncogenic activation. The results obtained showed no significant differences between the cells exposed to ELF-MF alone and the unexposed cells. Moreover, no synergistic or additive effects were observed after 4 or 16 h of pre-exposure to 1 mT ELF-MF or simultaneous exposure to ELF-MF combined with IR, H(2)O(2), or c-Myc activation.
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Affiliation(s)
- Yeung Bae Jin
- Advanced Radiation Technology Institute, Korea Atomic Energy Research Institute, Jeongeup, Korea
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12
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López-Díaz B, Mercado-Sáenz S, Martínez-Morillo M, Sendra-Portero F, Ruiz-Gómez MJ. Long-term exposure to a pulsed magnetic field (1.5 mT, 25 Hz) increases genomic DNA spontaneous degradation. Electromagn Biol Med 2013; 33:228-35. [DOI: 10.3109/15368378.2013.802245] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Affiliation(s)
- Beatriz López-Díaz
- Laboratory of Radiobiology, Department of Radiology and Physical Medicine, Faculty of Medicine, University of Malaga
MalagaSpain
| | - Silvia Mercado-Sáenz
- Laboratory of Radiobiology, Department of Radiology and Physical Medicine, Faculty of Medicine, University of Malaga
MalagaSpain
| | - Manuel Martínez-Morillo
- Laboratory of Radiobiology, Department of Radiology and Physical Medicine, Faculty of Medicine, University of Malaga
MalagaSpain
| | - Francisco Sendra-Portero
- Laboratory of Radiobiology, Department of Radiology and Physical Medicine, Faculty of Medicine, University of Malaga
MalagaSpain
| | - Miguel J. Ruiz-Gómez
- Laboratory of Radiobiology, Department of Radiology and Physical Medicine, Faculty of Medicine, University of Malaga
MalagaSpain
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13
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Hassan NS, Abdelkawi SA. Assessing of plasma protein denaturation induced by exposure to cadmium, electromagnetic fields and their combined actions on rat. Electromagn Biol Med 2013; 33:147-53. [DOI: 10.3109/15368378.2013.800101] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
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14
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Villarini M, Ambrosini MV, Moretti M, Dominici L, Taha E, Piobbico D, Gambelunghe C, Mariucci G. Brain hsp70 expression and DNA damage in mice exposed to extremely low frequency magnetic fields: A dose-response study. Int J Radiat Biol 2013; 89:562-70. [DOI: 10.3109/09553002.2013.782449] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
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15
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Bułdak RJ, Polaniak R, Bułdak L, Zwirska-Korczala K, Skonieczna M, Monsiol A, Kukla M, Duława-Bułdak A, Birkner E. Short-term exposure to 50 Hz ELF-EMF alters the cisplatin-induced oxidative response in AT478 murine squamous cell carcinoma cells. Bioelectromagnetics 2012; 33:641-51. [PMID: 22535669 DOI: 10.1002/bem.21732] [Citation(s) in RCA: 53] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2011] [Accepted: 04/08/2012] [Indexed: 01/18/2023]
Abstract
The aim of this study was to assess the influence of cisplatin and an extremely low frequency electromagnetic field (ELF-EMF) on antioxidant enzyme activity and the lipid peroxidation ratio, as well as the level of DNA damage and reactive oxygen species (ROS) production in AT478 carcinoma cells. Cells were cultured for 24 and 72 h in culture medium with cisplatin. Additionally, the cells were irradiated with 50 Hz/1 mT ELF-EMF for 16 min using a solenoid as a source of the ELF-EMF. The amount of ROS, superoxide dismutase (SOD) isoenzyme activity, glutathione peroxidase (GSH-Px) activity, DNA damage, and malondialdehyde (MDA) levels were assessed. Cells that were exposed to cisplatin exhibited a significant increase in ROS and antioxidant enzyme activity. The addition of ELF-EMF exposure to cisplatin treatment resulted in decreased ROS levels and antioxidant enzyme activity. A significant reduction in MDA concentrations was observed in all of the study groups, with the greatest decrease associated with treatment by both cisplatin and ELF-EMF. Cisplatin induced the most severe DNA damage; however, when cells were also irradiated with ELF-EMF, less DNA damage occurred. Exposure to ELF-EMF alone resulted in an increase in DNA damage compared to control cells. ELF-EMF lessened the effects of oxidative stress and DNA damage that were induced by cisplatin; however, ELF-EMF alone was a mild oxidative stressor and DNA damage inducer. We speculate that ELF-EMF exerts differential effects depending on the exogenous conditions. This information may be of value for appraising the pathophysiologic consequences of exposure to ELF-EMF.
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Affiliation(s)
- Rafał Jakub Bułdak
- Department of Physiology in Zabrze, Medical University of Silesia, Katowice, Poland.
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Lee HJ, Jin YB, Lee JS, Choi JI, Lee JW, Myung SH, Lee YS. Combined effects of 60 Hz electromagnetic field exposure with various stress factors on cellular transformation in NIH3T3 cells. Bioelectromagnetics 2011; 33:207-14. [PMID: 21898471 DOI: 10.1002/bem.20700] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2010] [Accepted: 07/26/2011] [Indexed: 11/07/2022]
Abstract
Epidemiological studies have suggested that extremely low-frequency magnetic fields (ELF-MF) are associated with an increased incidence of cancer. Studies using in vitro systems have reported mixed results for the effects of ELF-MF alone, and the World Health Organization (WHO) Research Agenda published in 2007 suggested that high priority research should include an evaluation of the co-carcinogenic effects of ELF-MF exposure using in vitro models. Here, the carcinogenic potential of ELF-MF exposure alone and in combination with various stress factors was investigated in NIH3T3 mouse fibroblasts using an in vitro cellular transformation assay. NIH3T3 cells were exposed to a 60 Hz ELF-MF (1 mT) alone or in combination with ionizing radiation (IR), hydrogen peroxide (H₂O₂), or c-Myc overexpression, and the resulting number of anchorage-independent colonies was counted. A 4 h exposure of NIH3T3 cells to ELF-MF alone produced no cell transformation. Moreover, ELF exposure did not influence the transformation activity of IR, H₂O₂, or activated c-Myc in our in vitro assay system, suggesting that 1 mT ELF-MF did not affect any additive or synergistic transformation activities in combination with stress factors such as IR, H₂O₂, or activated c-Myc in NIH3T3 cells.
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Affiliation(s)
- Hae-June Lee
- Division of Radiation Effects, Korea Institute of Radiological and Medical Sciences, Seoul, Korea
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Belyaev I. Toxicity and SOS response to ELF magnetic field and nalidixic acid in E. coli cells. Mutat Res 2011; 722:84-8. [PMID: 21453783 DOI: 10.1016/j.mrgentox.2011.03.011] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2010] [Accepted: 03/21/2011] [Indexed: 11/26/2022]
Abstract
Extremely low frequency (ELF) magnetic fields have previously been shown to affect conformation of chromatin and cell proliferation. Possible genotoxic and carcinogenic effects of ELF have also been discussed and tested. In this study, we analyzed the effect of ELF on chromatin conformation in E. coli GE499 cells by the anomalous viscosity time dependence (AVTD) technique. Possible genotoxic ELF effects at the specific combination of static and ELF magnetic fields, that has been proven to have effects on chromatin conformation, were investigated by clonogenic assay, cell growth kinetics, and analysis of SOS-response using inducible recA-lacZ fusion and the β-galactosidase assay. Genotoxic agent nalidixic acid (NAL) was used as positive control and in combination with ELF. Nalidixic acid at 3-30μg/ml decreased the AVTD peaks and induced cytotoxic effect. In contrast to NAL, ELF increased AVTD, stimulated cell growth, and increased cloning efficiency. These effects depended on frequency within the frequency range of 7-11Hz. While NAL induced SOS response, ELF exposure did not induce the recA-lacZ fusion. Exposure to ELF did not modify the genotoxic effects of NAL either. All together, the data show that ELF, under specific conditions of exposure, acted as nontoxic but cell growth stimulating agent.
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Affiliation(s)
- Igor Belyaev
- Department of Genetics, Microbiology and Toxicology, Stockholm University, S-106 91 Stockholm, Sweden.
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Giorgi G, Marcantonio P, Bersani F, Gavoçi E, Del Re B. Effect of extremely low frequency magnetic field exposure on DNA transposition in relation to frequency, wave shape and exposure time. Int J Radiat Biol 2011; 87:601-8. [PMID: 21504343 DOI: 10.3109/09553002.2011.570855] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
PURPOSE To examine the effect of extremely low frequency magnetic field (ELF-MF) exposure on transposon (Tn) mobility in relation to the exposure time, the frequency and the wave shape of the field applied. MATERIALS AND METHODS Two Escherichia coli model systems were used: (1) Cells unable to express β-galactosidase (LacZ(-)), containing a mini-transposon Tn10 element able to give ability to express β-galactosidase (LacZ(+)) upon its transposition; therefore in these cells transposition activity can be evaluated by analysing LacZ(+) clones; (2) cells carrying Fertility plasmid (F(+)), and a Tn5 element located on the chromosome; therefore in these cells transposition activity can be estimated by a bacterial conjugation assay. Cells were exposed to sinusoidal (SiMF) or pulsed-square wave (PMF) magnetic fields of various frequencies (20, 50, 75 Hz) and for different exposure times (15 and 90 min). RESULTS Both mini-Tn10 and Tn5 transposition decreased under SiMF and increased under PMF, as compared to sham exposure control. No significant difference was found between frequencies and between exposure times. CONCLUSIONS ELF-MF exposure affects transposition activity and the effects critically depend on the wave shape of the field, but not on the frequency and the exposure time, at least in the range observed.
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Affiliation(s)
- Gianfranco Giorgi
- Department of Evolutionary Experimental Biology, University of Bologna, Bologna, Italy
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Belyaev I. Toxicity and SOS-response to ELF magnetic fields and nalidixic acid in E. coli cells. Mutat Res 2011; 722:56-61. [PMID: 21497670 DOI: 10.1016/j.mrgentox.2011.03.012] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2010] [Revised: 01/11/2011] [Accepted: 03/15/2011] [Indexed: 12/24/2022]
Abstract
Extremely low-frequency magnetic fields (ELF-MF) have previously been shown to affect conformation of chromatin and cell proliferation. Possible genotoxic and carcinogenic effects of ELF-MF have also been discussed and tested. In this study, we analysed the effect of ELF-MF on chromatin conformation in E. coli GE499 cells by the anomalous viscosity time-dependence (AVTD) technique. Possible genotoxic effects of the specific combination of static and ELF-MF, which has been proven to affect chromatin conformation, were investigated by a clonogenic assay, by assessing cell-growth kinetics, and by analysis of the SOS-response by means of inducible recA-lacZ fusion-gene products and the β-galactosidase assay. The genotoxic agent nalidixic acid (NAL) was used as a positive control and in combination with ELF-MF. Nalidixic acid at 3-30μg/ml decreased the AVTD peaks and induced a cytotoxic effect. In contrast to NAL, ELF-MF fields increased AVTD, stimulated cell growth, and increased cloning efficiency. These effects depended on the frequency within the range of 7-11Hz. While NAL induced an SOS-response, exposure to ELF-MF did not induce the recA-lacZ fusion-gene product. Exposure to ELF-MF did not modify the genotoxic effects of NAL either. All together, the data show that ELF-MF, under specific conditions of exposure, acted as a non-toxic but cell-growth stimulating agent.
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Affiliation(s)
- Igor Belyaev
- Laboratory of Molecular Genetics, Cancer Research Institute, Bratislava, Slovak Republic.
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Morabito C, Guarnieri S, Fanò G, Mariggiò MA. Effects of acute and chronic low frequency electromagnetic field exposure on PC12 cells during neuronal differentiation. Cell Physiol Biochem 2011; 26:947-58. [PMID: 21220925 DOI: 10.1159/000324003] [Citation(s) in RCA: 50] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/13/2010] [Indexed: 11/19/2022] Open
Abstract
BACKGROUND/AIMS The purpose of this study was to provide information about the in vitro neuritogenesis during cell exposure to extremely low frequency electromagnetic fields (ELF-EMFs) of different intensities and durations using pheochromocytoma-derived cell line (PC12 cells) as neuronal model. METHODS Proliferative rates and neuritogenesis were tested by colorimetric assay and morphological analysis, respectively; reactive oxygen species (ROS) levels and intracellular Ca(2+) variations monitored using single cell videomicroscopy. RESULTS The long-lasting ELF-EMF exposure (0.1-1.0 mT) did not appear to significantly affect the biological response (proliferation and neuritogenesis). However, during the acute ELF-EMF exposure (30 min), in undifferentiated PC12 cells, there were increased ROS levels and decreased catalase activity, that, conversely, resulted increased after chronic exposure (7 days) at 1.0 mT. Acute exposure (0.1-1.0 mT) affected the spontaneous intracellular Ca(2+) variations in undifferentiated cells, in which basal intracellular Ca(2+) resulted increased after chronic exposure. In addition acute exposure affected cell response to a depolarizing agent, while basal membrane potential was not changed. CONCLUSION Even if further studies remain necessary to identify the ROS/intracellular Ca(2+)cross-talking pathway activated by ELF-EMF exposure, we support the hypothesis that ROS and Ca(2+) could be the cellular "primum movens" of the ELF-EMF induced effects on biological systems.
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Affiliation(s)
- Caterina Morabito
- Department Neuroscience and Imaging-Centro Studi sull'Invecchiamento (CeSI), G. d'Annunzio University of Chieti-Pescara, Chieti, Italy
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Ruiz-Gómez MJ, Sendra-Portero F, Martínez-Morillo M. Effect of 2.45 mT sinusoidal 50 Hz magnetic field on Saccharomyces cerevisiae strains deficient in DNA strand breaks repair. Int J Radiat Biol 2010; 86:602-11. [PMID: 20545572 DOI: 10.3109/09553001003734519] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
PURPOSE To investigate whether extremely-low frequency magnetic field (MF) exposure produce alterations in the growth, cell cycle, survival and DNA damage of wild type (wt) and mutant yeast strains. MATERIALS AND METHODS wt and high affinity DNA binding factor 1 (hdf1), radiation sensitive 52 (rad52), rad52 hdf1 mutant Saccharomyces cerevisiae strains were exposed to 2.45 mT, sinusoidal 50 Hz MF for 96 h. MF was generated by a pair of Helmholtz coils. During this time the growth was monitored by measuring the optical density at 600 nm and cell cycle evolution were analysed by microscopic morphological analysis. Then, yeast survival was assayed by the drop test and DNA was extracted and electrophoresed. RESULTS A significant increase in the growth was observed for rad52 strain (P = 0.005, Analysis of Variance [ANOVA]) and close to significance for rad52 hdf1 strain (P = 0.069, ANOVA). In addition, the surviving fraction values obtained for MF-exposed samples were in all cases less than for the controls, being the P value obtained for the whole set of MF-treated strains close to significance (P = 0.066, Student's t-test). In contrast, the cell cycle evolution and the DNA pattern obtained for wt and the mutant strains were not altered after exposure to MF. CONCLUSIONS The data presented in the current report show that the applied MF (2.45 mT, sinusoidal 50 Hz, 96 h) induces alterations in the growth and survival of S. cerevisiae strains deficient in DNA strand breaks repair. In contrast, the MF treatment does not induce alterations in the cell cycle and does not cause DNA damage.
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Affiliation(s)
- Miguel J Ruiz-Gómez
- Laboratory of Radiobiology, Department of Radiology and Physical Medicine, Faculty of Medicine, University of Malaga, Malaga, Spain.
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Mariucci G, Villarini M, Moretti M, Taha E, Conte C, Minelli A, Aristei C, Ambrosini MV. Brain DNA damage and 70-kDa heat shock protein expression in CD1 mice exposed to extremely low frequency magnetic fields. Int J Radiat Biol 2010; 86:701-10. [DOI: 10.3109/09553001003789588] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
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Ruiz-Gómez MJ, Martínez-Morillo M. Electromagnetic Fields and the Induction of DNA Strand Breaks. Electromagn Biol Med 2009; 28:201-14. [DOI: 10.1080/15368370802608696] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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Vijayalaxmi, Prihoda TJ. Genetic damage in mammalian somatic cells exposed to extremely low frequency electro-magnetic fields: A meta-analysis of data from 87 publications (1990–2007). Int J Radiat Biol 2009; 85:196-213. [DOI: 10.1080/09553000902748575] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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Koyama S, Sakurai T, Nakahara T, Miyakoshi J. Extremely low frequency (ELF) magnetic fields enhance chemically induced formation of apurinic/apyrimidinic (AP) sites in A172 cells. Int J Radiat Biol 2008; 84:53-9. [PMID: 17852556 DOI: 10.1080/09553000701616064] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
Abstract
PURPOSE To detect the effects of extremely low frequency (ELF) magnetic fields, the number of apurinic/apyrimidinic (AP) sites in human glioma A172 cells was measured following exposure to ELF magnetic fields. MATERIALS AND METHODS The cells were exposed to an ELF magnetic field alone, to genotoxic agents (methyl methane sulfonate (MMS) and hydrogen peroxide (H2O2)) alone, or to an ELF magnetic field with the genotoxic agents. After exposure, DNA was extracted, and the number of AP sites was measured. RESULTS There was no difference in the number of AP sites between cells exposed to an ELF magnetic field and sham controls. With MMS or H2O2 alone, the number of AP sites increased with longer treatment times. Exposure to an ELF magnetic field in combination with the genotoxic agents increased AP-site levels compared with the genotoxic agents alone. CONCLUSIONS Our results suggest that the number of AP sites induced by MMS or H2O2 is enhanced by exposure to ELF magnetic fields at 5 millitesla (mT). This may occur because such exposure can enhance the activity or lengthen the lifetime of radical pairs.
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Affiliation(s)
- Shin Koyama
- Department of Radiological Technology, School of Health Sciences, Faculty of Medicine, Hirosaki University, Hirosaki, Japan
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Falone S, Grossi MR, Cinque B, D'Angelo B, Tettamanti E, Cimini A, Di Ilio C, Amicarelli F. Fifty hertz extremely low-frequency electromagnetic field causes changes in redox and differentiative status in neuroblastoma cells. Int J Biochem Cell Biol 2007; 39:2093-106. [PMID: 17662640 DOI: 10.1016/j.biocel.2007.06.001] [Citation(s) in RCA: 65] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2007] [Revised: 05/31/2007] [Accepted: 06/03/2007] [Indexed: 11/30/2022]
Abstract
The current study was designed to establish whether extremely low-frequency electromagnetic fields might affect neuronal homeostasis through redox-sensitive mechanisms. To this end, intracellular reactive oxygen species production, antioxidant and glutathione-based detoxifying capability and genomic integrity after extremely low-frequency electromagnetic fields exposure were investigated. Moreover, we also studied potential extremely low-frequency electromagnetic fields-dependent changes in the proliferative and differentiative cellular status. Results seem to support redox-mediated extremely low-frequency electromagnetic fields effects on biological models as, although no major oxidative damage was detected, after exposure we observed a positive modulation of antioxidant enzymatic expression, as well as a significant increase in reduced glutathione level, indicating a shift of cellular environment towards a more reduced state. In addition, extremely low-frequency electromagnetic fields treatment induced a more differentiated phenotype as well as an increased expression in peroxisome proliferators-activated receptor isotype beta, a class of transcription factors related to neuronal differentiation and cellular stress response. As second point, to deepen how extremely low-frequency electromagnetic fields treatment could affect neuroblastoma cell antioxidant capacity, we examined the extremely low-frequency electromagnetic fields-dependent modifications of cell susceptibility to pro-oxidants. Results clearly showed that 50 Hz extremely low-frequency electromagnetic fields exposure reduces cell tolerance towards oxidative attacks.
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Affiliation(s)
- Stefano Falone
- Department of Biomedical Sciences, Excellent Center on Aging Studies, Faculty of Medicine G. d'Annunzio, Via dei Vestini, 66013 Chieti, Italy
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