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Nieminen V, Martikainen MV, Kalliomäki S, Virén T, Seppälä J, Juutilainen J, Naarala J, Luukkonen J. 50 Hz magnetic field influences caspase-3 activity and cell cycle distribution in ionizing radiation exposed SH-SY5Y neuroblastoma cells. Int J Radiat Biol 2024; 100:1183-1192. [PMID: 38924721 DOI: 10.1080/09553002.2024.2369105] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2024] [Revised: 04/29/2024] [Accepted: 06/12/2024] [Indexed: 06/28/2024]
Abstract
PURPOSE Earlier evidence suggests that extremely low frequency magnetic fields (ELF MFs) can modify the effects of carcinogenic agents. However, the studies conducted so far with ionizing radiation as the co-exposure agent are sparse and have provided inconclusive results. We investigated whether 50 Hz MFs alone, or in combination with ionizing radiation alter cell biological variables relevant to cancer and the biological effects of ionizing radiation. MATERIALS AND METHODS Human SH-SY5Y neuroblastoma cells were sham exposed or exposed to 100 or 500 µT MF for 24 h either before or after ionizing radiation exposure (0, 0.4 or 2 Gy). After the exposures, cells were assayed for viability, clonogenicity, reactive oxygen species, caspase-3 activity, and cell cycle distribution. Cell cycle distribution was assayed with propidium iodide staining followed by flow cytometry analysis and ROS levels were assayed together with cell viability by double staining with DeepRed and Sytox Blue followed by flow cytometry analysis. RESULTS Increased caspase-3 activity was observed in cells exposed to 500 µT MF before or after ionizing radiation. Furthermore, exposure to the 500 µT MF after the ionizing radiation decreased the percentage of cells in S-phase. No changes in the ROS levels, clonogenicity, or viability of the cells were observed in the MF exposed groups compared to the corresponding sham exposed groups, and no MF effects were observed in cells exposed at 100 µT. CONCLUSIONS Only the 500 µT magnetic flux density affected SH-SY5Y cells significantly. The effects were small but may nevertheless help to understand how MFs modify the effects of ionizing radiation. The increase in caspase-3 activity may not reflect effects on apoptosis, as no changes were observed in the subG1 phase of the cell cycle. In contrast to some earlier findings, 50 Hz MF exposure after ionizing radiation was not less effective than MF treatment given prior to ionizing radiation.
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Affiliation(s)
- Valtteri Nieminen
- Department of Environmental and Biological Sciences, University of Eastern Finland, Kuopio, Finland
| | - Maria-Viola Martikainen
- Department of Environmental and Biological Sciences, University of Eastern Finland, Kuopio, Finland
| | - Saija Kalliomäki
- Department of Environmental and Biological Sciences, University of Eastern Finland, Kuopio, Finland
| | - Tuomas Virén
- Center of Oncology, Kuopio University Hospital, Kuopio, Finland
| | - Jan Seppälä
- Center of Oncology, Kuopio University Hospital, Kuopio, Finland
| | - Jukka Juutilainen
- Department of Environmental and Biological Sciences, University of Eastern Finland, Kuopio, Finland
| | - Jonne Naarala
- Department of Environmental and Biological Sciences, University of Eastern Finland, Kuopio, Finland
| | - Jukka Luukkonen
- Department of Environmental and Biological Sciences, University of Eastern Finland, Kuopio, Finland
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Gholipour Hamedani B, Goliaei B, Shariatpanahi SP, Nezamtaheri M. An overview of the biological effects of extremely low frequency electromagnetic fields combined with ionizing radiation. PROGRESS IN BIOPHYSICS AND MOLECULAR BIOLOGY 2022; 172:50-59. [PMID: 35513112 DOI: 10.1016/j.pbiomolbio.2022.04.008] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/17/2021] [Revised: 04/09/2022] [Accepted: 04/22/2022] [Indexed: 06/14/2023]
Abstract
By growing the electrical power networks and electronic devices, electromagnetic fields (EMF) have become an inseparable part of the modern world. Considering the inevitable exposure to a various range of EMFs, especially at extremely low frequencies (ELF-EMF), investigating the biological effects of ELF-EMFs on biological systems became a global issue. The possible adverse consequences of these exposures were studied, along with their potential therapeutic capabilities. Also, their biological impacts in combination with other chemical and physical agents, specifically ionizing radiation (IR), as a co-carcinogen or as adjuvant therapy in combination with radiotherapy were explored. Here, we review the results of several in-vitro and in-vivo studies and discuss some proposed possible mechanisms of ELF-EMFs' actions in combination with IR. The results of these experiments could be fruitful to develop more precise safety standards for environmental ELF-EMFs exposures. Furthermore, it could evaluate the therapeutic capacities of ELF-EMFs alone or as an improver of radiotherapy.
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Affiliation(s)
- Bahareh Gholipour Hamedani
- Laboratory of Biophysics and Molecular Biology, Institute of Biochemistry and Biophysics (IBB), University of Tehran, Tehran, Iran
| | - Bahram Goliaei
- Laboratory of Biophysics and Molecular Biology, Institute of Biochemistry and Biophysics (IBB), University of Tehran, Tehran, Iran.
| | - Seyed Peyman Shariatpanahi
- Laboratory of Biophysics and Molecular Biology, Institute of Biochemistry and Biophysics (IBB), University of Tehran, Tehran, Iran
| | - Maryamsadat Nezamtaheri
- Laboratory of Biophysics and Molecular Biology, Institute of Biochemistry and Biophysics (IBB), University of Tehran, Tehran, Iran
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Martínez M, Úbeda A, Martínez‑Botas J, Trillo M. Field exposure to 50 Hz significantly affects wild‑type and unfolded p53 expression in NB69 neuroblastoma cells. Oncol Lett 2022; 24:295. [PMID: 35949615 PMCID: PMC9353226 DOI: 10.3892/ol.2022.13415] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2022] [Accepted: 06/17/2022] [Indexed: 11/26/2022] Open
Abstract
Previous studies have shown that intermittent exposure to a 50 Hz, 100 µT sinusoidal magnetic field (MF) promotes proliferation of human neuroblastoma cells, NB69. This effect is mediated by activation of the epidermal growth factor receptor through a free radical-dependent activation of the p38 pathway. The present study investigated the possibility that the oxidative stress-sensitive protein p53 is a potential target of the MF, and that field exposure can affect the protein expression. To that end, NB69 cells were exposed to short intervals of 30 to 120 min to the aforementioned MF parameters. Two specific anti-p53 antibodies that allow discrimination between the wild and unfolded forms of p53 were used to study the expression and cellular distribution of both isoforms of the protein. The expression of the antiapoptotic protein Bcl-2, whose regulation is mediated by p53, was also analyzed. The obtained results revealed that MF exposure induced increases in p53 gene expression and in protein expression of the wild-type form of p53. Field exposure also caused overexpression of the unfolded form of p53, together with changes in the nuclear/cytoplasmic distribution of both forms of the protein. The expression of protein Bcl-2 was also significantly increased in response to the MF. As a whole, these results indicated that the MF is capable of interacting with the function, distribution and conformation of protein p53. Such interactions could be involved in previously reported MF effects on NB69 proliferation promotion.
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Affiliation(s)
- María Martínez
- Bioelectromagnetics Service, Department of Research, Ramón y Cajal University Hospital, Ramón Y Cajal Institute of Health Research, 28034 Madrid
| | - Alejandro Úbeda
- Bioelectromagnetics Service, Department of Research, Ramón y Cajal University Hospital, Ramón Y Cajal Institute of Health Research, 28034 Madrid
| | - Javier Martínez‑Botas
- Biochemistry Service, Department of Research, Ramón y Cajal University Hospital, Ramón Y Cajal Institute of Health Research, 28034 Madrid, Spain
| | - María Trillo
- Bioelectromagnetics Service, Department of Research, Ramón y Cajal University Hospital, Ramón Y Cajal Institute of Health Research, 28034 Madrid
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Mansourian M, Firoozabadi M, Hassan ZM. The role of 217-Hz ELF magnetic fields emitted from GSM mobile phones on electrochemotherapy mechanisms. Electromagn Biol Med 2020; 39:239-249. [PMID: 32410511 DOI: 10.1080/15368378.2020.1762635] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
Abstract
Electrochemotherapy (ECT), the combination of electric pulses (EPs) and an anticancer drug, is a type of cancer treatment method. We investigated the effect of 217-Hz magnetic fields (MFs) similar to that generated by GSM900 mobile phones, as intervening factors, on proposed mechanisms of ECT including permeability, tumor hypoxia and immune system response. The 4T1 cells were exposed to extremely low-frequency (ELF)-MFs at 93, 120 or 159 µT intensities, generated by Helmholtz coils 10 min, and then put in individual groups, comprising no treatment, chemotherapy, EPs or ECT. The cell viability was evaluated. Then, two treatment protocols were selected for in vivo experiments. The mice with 4T1 tumor cells were exposed to ELF-MFs 10 min/day until the day their tumors reached 8 mm in diameter. Then, the tumors were treated to ECT. Tumor hypoxia and immune system response were analyzed through immunohistochemistry assay and enzyme-linked immunosorbent assay technique, respectively. The results in vitro indicated a significant decreased ECT efficacy of 60 V/cm, 5 kHz at the flux density of 93 µT. The results in vivo showed that pre-exposure to ELF-MFs could increase tumor hypoxia induced by ECT. In addition, exposure to ELF-MFs before ECT caused a significant increase in interferon-γ/interleukin-4 in comparison with ECT alone. More studies, including studies on the effect of ELF-MFs emitted from mobile phones on tumor volume changes induced by ECT, are needed to elucidate how the process of ECT is influenced by the MFs.
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Affiliation(s)
- Mahsa Mansourian
- Department of Medical Physics, Faculty of Medical Science, Tarbiat Modares University , Tehran, Iran
| | - Mohammad Firoozabadi
- Department of Medical Physics, Faculty of Medical Science, Tarbiat Modares University , Tehran, Iran
| | - Zuhair Mohammad Hassan
- Department of Immunology, Faculty of Medical Science, Tarbiat Modares University , Tehran, Iran
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Sun C, Wei X, Yimaer A, Xu Z, Chen G. Ataxia telangiectasia mutated deficiency does not result in genetic susceptibility to 50 Hz magnetic fields exposure in mouse embryonic fibroblasts. Bioelectromagnetics 2018; 39:476-484. [PMID: 30091795 DOI: 10.1002/bem.22140] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2018] [Accepted: 07/16/2018] [Indexed: 12/31/2022]
Abstract
Extremely low frequency magnetic field (ELF-MF) has been classified as a possible carcinogen to humans by the International Agency for Research on Cancer [2002]. However, debate on the genotoxic effects of ELF-MF has continued due to lack of sufficient experimental evidence. Ataxia telangiectasia mutated (ATM) plays a central role in DNA damage repair; its deficiency can result in cellular sensitivity to DNA-damaging agents. To evaluate the genotoxicity of ELF-MF, we investigated the effects of 50 Hz MF on DNA damage in ATM-proficient (Atm+/+ ) mouse embryonic fibroblasts (MEFs) and ATM-deficient (Atm-/- ) MEFs, a radiosensitive cell line. Results showed no significant difference in average number of γH2AX foci per cell (9.37 ± 0.44 vs. 9.08 ± 0.28, P = 0.58) or percentage of γH2AX foci positive cells (49.22 ± 1.86% vs. 49.74 ± 1.44%, P = 0.83) between sham and exposure groups when Atm+/+ MEFs were exposed to 50 Hz MF at 2.0 mT for 15 min. Extending exposure duration to 1 or 24 h did not significantly change γH2AX foci formation in Atm+/+ MEFs. Similarly, the exposure did not significantly affect γH2AX foci formation in Atm-/- MEFs. Furthermore, 50 Hz MF exposure also did not significantly influence DNA fragmentation, cell viability, or cell cycle progression in either cell types. In conclusion, exposure to 50 Hz MF did not induce significant DNA damage in either Atm+/+ or Atm-/- MEFs under the reported experimental conditions. Bioelectromagnetics. 39:476-484, 2018. © 2018 Wiley Periodicals, Inc.
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Affiliation(s)
- Chuan Sun
- Bioelectromagnetics Laboratory, Zhejiang University School of Medicine, Hangzhou, China.,Institute of Hygiene, Zhejiang Academy of Medical Sciences, Hangzhou, China
| | - Xiaoxia Wei
- Bioelectromagnetics Laboratory, Zhejiang University School of Medicine, Hangzhou, China
| | - Aziguli Yimaer
- Bioelectromagnetics Laboratory, Zhejiang University School of Medicine, Hangzhou, China
| | - Zhengping Xu
- Bioelectromagnetics Laboratory, Zhejiang University School of Medicine, Hangzhou, China.,Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases, Zhejiang University, Hangzhou, China.,Institute of Environmental Health, Zhejiang University School of Public Health, Hangzhou, China
| | - Guangdi Chen
- Bioelectromagnetics Laboratory, Zhejiang University School of Medicine, Hangzhou, China.,Institute of Environmental Health, Zhejiang University School of Public Health, Hangzhou, China
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6
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Destefanis M, Viano M, Leo C, Gervino G, Ponzetto A, Silvagno F. Extremely low frequency electromagnetic fields affect proliferation and mitochondrial activity of human cancer cell lines. Int J Radiat Biol 2015; 91:964-72. [PMID: 26762464 DOI: 10.3109/09553002.2015.1101648] [Citation(s) in RCA: 50] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Abstract
PURPOSE To date, the effects of electromagnetic fields on cell metabolism have been overlooked. The objective of the present study was to investigate the influence of extremely low frequency electromagnetic fields (ELF-EMF) over mitochondrial metabolism and the consequent impact on cancer cell growth. MATERIALS AND METHODS The effects of ELF-EMF on cancer growth were investigated in several human cancer cell lines by crystal violet assay. The modulation of mitochondrial activity was assessed by cytofluorimetric evaluation of membrane potential and by real-time quantification of mitochondrial transcription. Moreover the expression of several mitochondrial proteins and their levels in the organelle were evaluated. RESULTS The long-term exposure to ELF-EMF reduced the proliferation of several cancer cell lines and the effect was associated to an increased mitochondrial activity without evident changes in ATP levels. The results of our experiments excluded a transcriptional modulation of mitochondrial respiratory complexes, rather suggesting that ELF-EMF increased the energy demand. The altered mitochondrial metabolism led to changes in mitochondrial protein profile. In fact we found a downregulated expression of mitochondrial phospho-ERK, p53 and cytochrome c. CONCLUSION The results of the present study indicate that ELF-EMF can negatively modulate cancer cell growth increasing respiratory activity of cells and altering mitochondrial protein expression.
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Affiliation(s)
| | - Marta Viano
- a Department of Oncology , University of Torino , Torino , Italy
| | - Christian Leo
- b Department of Medical Sciences , University of Torino , Torino , Italy
| | | | - Antonio Ponzetto
- b Department of Medical Sciences , University of Torino , Torino , Italy
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7
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Tian F, Clift MJ, Casey A, Del Pino P, Pelaz B, Conde J, Byrne HJ, Rothen-Rutishauser B, Estrada G, de la Fuente JM, Stoeger T. Investigating the role of shape on the biological impact of gold nanoparticles in vitro. Nanomedicine (Lond) 2015; 10:2643-57. [PMID: 26377045 DOI: 10.2217/nnm.15.103] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Abstract
AIM To investigate the influence of gold nanoparticle geometry on the biochemical response of Calu-3 epithelial cells. MATERIALS & METHODS Spherical, triangular and hexagonal gold nanoparticles (GNPs) were used. The GNP-cell interaction was assessed via atomic absorption spectroscopy (AAS) and transmission electron microscopy (TEM). The biochemical impact of GNPs was determined over 72 h at (0.0001-1 mg/ml). RESULTS At 1 mg/ml, hexagonal GNPs reduced Calu-3 viability below 60%, showed increased reactive oxygen species production and higher expression of proapoptotic markers. A cell mass burden of 1:2:12 as well as number of GNPs per cell (2:1:3) was observed for spherical:triangular:hexagonal GNPs. CONCLUSION These findings do not suggest a direct shape-toxicity effect. However, do highlight the contribution of shape towards the GNP-cell interaction which impacts upon their intracellular number, mass and volume dose.
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Affiliation(s)
- Furong Tian
- Comprehensive Pneumology Centre, Institute of Lung Biology & Disease, Helmholtz Zentrum München, Neuherberg, Germany.,Nanolab Research Centre, FOCAS Research Institute, Dublin Institute of Technology, Camden Row, Dublin, Ireland
| | - Martin Jd Clift
- BioNanomaterials, Adolphe Merkle Institute, University of Fribourg, Switzerland
| | - Alan Casey
- Nanolab Research Centre, FOCAS Research Institute, Dublin Institute of Technology, Camden Row, Dublin, Ireland
| | | | - Beatriz Pelaz
- Fachbereich Physik, Philipps Universität Marburg, Marburg, Germany
| | - João Conde
- Massachusetts Institute of Technology, Institute for Medical Engineering & Science, Harvard-MIT Division for Health Sciences & Technology, E25-449 Cambridge, MA, USA
| | - Hugh J Byrne
- Nanolab Research Centre, FOCAS Research Institute, Dublin Institute of Technology, Camden Row, Dublin, Ireland
| | | | - Giovani Estrada
- Institute of Bioinformatics, Helmholtz Zentrum München, Neuherberg, Germany
| | - Jesús M de la Fuente
- Instituto de Ciencia de Materiales de Aragon CSIC-Universidad de Zaragoza, Spain
| | - Tobias Stoeger
- Comprehensive Pneumology Centre, Institute of Lung Biology & Disease, Helmholtz Zentrum München, Neuherberg, Germany
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8
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Conde J, Tian F, Hernandez Y, Bao C, Baptista PV, Cui D, Stoeger T, de la Fuente JM. RNAi-based glyconanoparticles trigger apoptotic pathways for in vitro and in vivo enhanced cancer-cell killing. NANOSCALE 2015; 7:9083-91. [PMID: 25924183 DOI: 10.1039/c4nr05742b] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/14/2023]
Abstract
Gold glyconanoparticles (GlycoNPs) are full of promise in areas like biomedicine, biotechnology and materials science due to their amazing physical, chemical and biological properties. Here, siRNA GlycoNPs (AuNP@PEG@Glucose@siRNA) in comparison with PEGylated GlycoNPs (AuNP@PEG@Glucose) were applied in vitro to a luciferase-CMT/167 adenocarcinoma cancer cell line and in vivo via intratracheal instillation directly into the lungs of B6 albino mice grafted with luciferase-CMT/167 adenocarcinoma cells. siRNA GlycoNPs but not PEGylated GlycoNPs induced the expression of pro-apoptotic proteins such as Fas/CD95 and caspases 3 and 9 in CMT/167 adenocarcinoma cells in a dose dependent manner, independent of the inflammatory response, evaluated by bronchoalveolar lavage cell counting. Moreover, in vivo pulmonary delivered siRNA GlycoNPs were capable of targeting c-Myc gene expression (a crucial regulator of cell proliferation and apoptosis) via in vivo RNAi in tumour tissue, leading to an ∼80% reduction in tumour size without associated inflammation.
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Affiliation(s)
- João Conde
- Massachusetts Institute of Technology, Institute for Medical Engineering and Science, Harvard-MIT Division for Health Sciences and Technology, E25-449 Cambridge, Massachusetts, USA
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Brisdelli F, Bennato F, Bozzi A, Cinque B, Mancini F, Iorio R. ELF-MF attenuates quercetin-induced apoptosis in K562 cells through modulating the expression of Bcl-2 family proteins. Mol Cell Biochem 2014; 397:33-43. [DOI: 10.1007/s11010-014-2169-1] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2014] [Accepted: 07/24/2014] [Indexed: 11/24/2022]
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10
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Motawi TK, Darwish HA, Moustafa YM, Labib MM. Biochemical Modifications and Neuronal Damage in Brain of Young and Adult Rats After Long-Term Exposure to Mobile Phone Radiations. Cell Biochem Biophys 2014; 70:845-55. [DOI: 10.1007/s12013-014-9990-8] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
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Podda MV, Leone L, Barbati SA, Mastrodonato A, Li Puma DD, Piacentini R, Grassi C. Extremely low-frequency electromagnetic fields enhance the survival of newborn neurons in the mouse hippocampus. Eur J Neurosci 2013; 39:893-903. [DOI: 10.1111/ejn.12465] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2013] [Revised: 11/26/2013] [Accepted: 11/28/2013] [Indexed: 01/12/2023]
Affiliation(s)
- Maria V. Podda
- Institute of Human Physiology; Medical School; Università Cattolica del Sacro Cuore; Largo Francesco Vito 1 00168 Rome Italy
| | - Lucia Leone
- Institute of Human Physiology; Medical School; Università Cattolica del Sacro Cuore; Largo Francesco Vito 1 00168 Rome Italy
| | - Saviana A. Barbati
- Institute of Human Physiology; Medical School; Università Cattolica del Sacro Cuore; Largo Francesco Vito 1 00168 Rome Italy
| | - Alessia Mastrodonato
- Institute of Human Physiology; Medical School; Università Cattolica del Sacro Cuore; Largo Francesco Vito 1 00168 Rome Italy
| | - Domenica D. Li Puma
- Institute of Human Physiology; Medical School; Università Cattolica del Sacro Cuore; Largo Francesco Vito 1 00168 Rome Italy
| | - Roberto Piacentini
- Institute of Human Physiology; Medical School; Università Cattolica del Sacro Cuore; Largo Francesco Vito 1 00168 Rome Italy
| | - Claudio Grassi
- Institute of Human Physiology; Medical School; Università Cattolica del Sacro Cuore; Largo Francesco Vito 1 00168 Rome Italy
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Mizuno K, Narita E, Yamada M, Shinohara N, Miyakoshi J. ELF magnetic fields do not affect cell survival and DNA damage induced by ultraviolet B. Bioelectromagnetics 2013; 35:108-15. [PMID: 24123106 DOI: 10.1002/bem.21821] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2013] [Accepted: 09/12/2013] [Indexed: 11/07/2022]
Abstract
We investigated whether extremely low frequency (ELF) magnetic field exposure has modification effects on cell survival after ultraviolet B (UV-B) irradiation and on repair process of DNA damage induced by UV-B irradiation in WI38VA13 subcloned 2RA and XP2OS(SV) cells. The ELF magnetic field exposure was conducted using a Helmholtz coil-based system that was designed to generate a sinusoidal magnetic field at 5 mT and 60 Hz. Cell survival was assessed by WST assay after UV-B irradiation at 20-80 J/m(2) , ELF magnetic field exposure for 24 h, followed by incubation for 48 h. DNA damage was assessed by quantification of cyclobutane pyrimidine dimer formation and 6-4 photoproduct formation using ELISA after UV-B irradiation at 20-80 J/m(2) followed by ELF magnetic field exposure for 24 h. No significant changes were observed in cell survival between ELF magnetic field and sham exposures. Similarly, DNA damage induced by UV-B irradiation did not change significantly following ELF magnetic field exposure. Our results suggest that ELF magnetic field exposure at 5 mT does not have modification effect on cell survival after UV-B irradiation and on repair process of DNA damage induced by UV-B irradiation.
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Affiliation(s)
- Kohei Mizuno
- Research Institute for Sustainable Humanosphere, Kyoto University, Uji, Japan; Power Engineering R&D Center, Kansai Electric Power Company, Osaka, Japan
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Akdag MZ, Dasdag S, Uzunlar AK, Ulukaya E, Oral AY, Çelik N, Akşen F. Can safe and long-term exposure to extremely low frequency (50 Hz) magnetic fields affect apoptosis, reproduction, and oxidative stress? Int J Radiat Biol 2013; 89:1053-60. [PMID: 23786626 DOI: 10.3109/09553002.2013.817705] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
PURPOSE To determine whether 50 Hz extremely low frequency-magnetic fields (ELF-MF) affects apoptotic processes, oxidative damage, and reproductive characteristics such as sperm count and morphology in rat testes. MATERIALS AND METHODS Thirty male Sprague-Dawley rats were used in the present study, which were divided into three groups (sham group, n = 10, and two experimental groups, n = 10 for each group). Rats in the experimental group were exposed to 100 and 500 μT ELF-MF (2 h/day, 7 days/week, for 10 months) corresponding to exposure levels that are considered safe for humans. The same experimental procedures were applied to the sham group, but the ELF generator was turned off. Tissues from the testes were immunohistochemically stained for active (cleaved) caspase-3 in order to measure the apoptotic index by a semi-quantitative scoring system. The levels of catalase (CAT), malondialdehyde (MDA), myeloperoxidase (MPO), total antioxidative capacity (TAC), total oxidant status (TOS), and oxidative stress index (OSI) were also measured. Additionally, epididymal sperm count and sperm morphology was evaluated. RESULTS There were no significant differences in the reproductive and oxidative stress parameters between the sham group and the exposed groups (p > 0.05). While no difference was observed between the final apoptosis score of the sham and the 100 μT ELF-MF group (p > 0.05), the final apoptosis score was higher in the 500 μT ELF-MF exposure group than in the sham group (p < 0.05). CONCLUSION Long-term exposure to 100 μT and 500 μT ELF-MF did not affect oxidative or antioxidative processes, lipid peroxidation, or reproductive components such as sperm count and morphology in testes tissue of rats. However, long-term exposure to 500 μT ELF-MF did affect active-caspase-3 activity, which is a well-known apoptotic indicator.
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Polidori E, Zeppa S, Potenza L, Martinelli C, Colombo E, Casadei L, Agostini D, Sestili P, Stocchi V. Gene expression profile in cultured human umbilical vein endothelial cells exposed to a 300 mT static magnetic field. Bioelectromagnetics 2011; 33:65-74. [PMID: 21755520 DOI: 10.1002/bem.20686] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2011] [Accepted: 04/27/2011] [Indexed: 01/28/2023]
Abstract
In a previous investigation we reported that exposure to a moderate (300 mT) static magnetic field (SMF) causes transient DNA damage and promotes mitochondrial biogenesis in human umbilical vein endothelial cells (HUVECs). To better understand the response of HUVECs to the 300 mT SMF, a high-quality subtracted cDNA library representative of genes induced in cells after 4 h of static magnetic exposure was constructed. The global gene expression profile showed that several genes were induced after the SMF exposure. The characterized clones are involved in cell metabolism, energy, cell growth/division, transcription, protein synthesis, destination and storage, membrane injury, DNA damage/repair, and oxidative stress response. Quantitative real-time polymerase chain reaction (qRT-PCR) experiments were performed at 4 and 24 h on four selected genes. Their expression profiles suggest that HUVEC's response to SMF exposure is transient. Furthermore, compared to control cells, an up-regulation of several genes involved in cell growth and division was observed. This up-regulation is likely to be the cause of the slight, but significant, increase in cell proliferation at 12 h post-treatment. These results provide additional support to the notion that SMFs may be harmless to human health, and could support the rationale for their possible use in medical treatments.
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Affiliation(s)
- Emanuela Polidori
- Dipartimento di Scienze Biomolecolari, Università degli Studi di Urbino "Carlo Bo", Italy.
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Akdag MZ, Dasdag S, Ulukaya E, Uzunlar AK, Kurt MA, Taşkin A. Effects of extremely low-frequency magnetic field on caspase activities and oxidative stress values in rat brain. Biol Trace Elem Res 2010; 138:238-49. [PMID: 20177816 DOI: 10.1007/s12011-010-8615-3] [Citation(s) in RCA: 44] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/09/2009] [Accepted: 01/15/2010] [Indexed: 10/19/2022]
Abstract
This study was aimed to investigate the effect of extremely low-frequency magnetic field (ELF-MF) on apoptosis and oxidative stress values in the brain of rat. Rats were exposed to 100 and 500 µT ELF-MF, which are the safety standards of public and occupational exposure for 2 h/day for 10 months. Brain tissues were immunohistochemically stained for the active (cleaved) caspase-3 in order to measure the apoptotic index by a semi-quantitative scoring system. In addition, the levels of catalase (CAT), malondialdehyde (MDA), myeloperoxidase (MPO), total antioxidative capacity (TAC), total oxidant status (TOS), and oxidative stress index (OSI) were measured in rat brain. Final score of apoptosis and MPO activity were not significantly different between the groups. CAT activity decreased in both exposure groups (p < 0.05), while TAC was found to be lower in ELF 500 group than those in ELF-100 and sham groups (p < 0.05). MDA, TOS, and OSI values were found to be higher in ELF-500 group than those in ELF-100 and sham groups (p < 0.05). In conclusion, apoptosis was not changed by long-term ELF-MF exposure, while both 100 and 500 µT ELF-MF exposure induced toxic effect in the rat brain by increasing oxidative stress and diminishing antioxidant defense system.
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Affiliation(s)
- Mehmet Zulkuf Akdag
- Department of Biophysics, Medical School of Dicle University, 21280 Diyarbakir, Turkey
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16
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Abstract
It is becoming evident that failure in the removal of dying cells causes and/or promotes the onset of chronic diseases. Impairment of phagocytosis of apoptotic cells can be due not only to genetic or molecular malfunctioning but also to external/environmental factors. Two of these environmental factors have been recently reported to down regulate the clearance of apoptotic cells: cigarette smoke and static magnetic fields. Cigarette smoke contains highly reactive carbonyls that modify proteins which directly/indirectly affects cellular function. Human macrophages interacting with carbonyl or cigarette smoke modified extracellular matrix (ECM) proteins dramatically down regulated their ability to phagocytose apoptotic neutrophils. It was postulated that changes in the ECM environment as a result of cigarette smoke affect the ability of macrophages to remove apoptotic cells. This decreased phagocytic activity was as a result of sequestration of receptors involved in the uptake of apoptotic cells towards that of recognition of carbonyl adducts on the modified ECM proteins leading to increased macrophage adhesion. Downregulation of the phagocytosis of apoptotic cells was also described when performed in presence of static magnetic fields (SMFs) of moderate intensity. SMFs have been reported to perturb distribution of membrane proteins and glycoproteins, receptors, cytoskeleton and trans-membrane fluxes of different ions, especially calcium [Ca(2+)]i, that in turn, interfere with many different physiological activities, including phagocytosis. The effects of cigarette smoke and SMF on the phagocytosis of dying cells will be here discussed.
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Affiliation(s)
- Luciana Dini
- Department Biological and Environmental Science and Technology, University of the Salento, Lecce, Italy.
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Cifra M, Fields JZ, Farhadi A. Electromagnetic cellular interactions. PROGRESS IN BIOPHYSICS AND MOLECULAR BIOLOGY 2010; 105:223-46. [PMID: 20674588 DOI: 10.1016/j.pbiomolbio.2010.07.003] [Citation(s) in RCA: 136] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/21/2010] [Accepted: 07/21/2010] [Indexed: 12/14/2022]
Abstract
Chemical and electrical interaction within and between cells is well established. Just the opposite is true about cellular interactions via other physical fields. The most probable candidate for an other form of cellular interaction is the electromagnetic field. We review theories and experiments on how cells can generate and detect electromagnetic fields generally, and if the cell-generated electromagnetic field can mediate cellular interactions. We do not limit here ourselves to specialized electro-excitable cells. Rather we describe physical processes that are of a more general nature and probably present in almost every type of living cell. The spectral range included is broad; from kHz to the visible part of the electromagnetic spectrum. We show that there is a rather large number of theories on how cells can generate and detect electromagnetic fields and discuss experimental evidence on electromagnetic cellular interactions in the modern scientific literature. Although small, it is continuously accumulating.
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Affiliation(s)
- Michal Cifra
- Institute of Photonics and Electronics, Academy of Sciences of the Czech Republic, Prague, Czech Republic.
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18
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DASDAG SULEYMAN, AKDAG MZULKUF, ULUKAYA ENGIN, UZUNLAR ALIKEMAL, OCAK ALIRIZA. Effect of Mobile Phone Exposure on Apoptotic Glial Cells and Status of Oxidative Stress in Rat Brain. Electromagn Biol Med 2009; 28:342-54. [DOI: 10.3109/15368370903206556] [Citation(s) in RCA: 64] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
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Yilmaz F, Dasdag S, Akdag MZ, Kilinc N. Whole-Body Exposure of Radiation Emitted from 900 MHz Mobile Phones Does Not Seem to Affect the Levels of Anti-Apoptotic bcl-2 Protein. Electromagn Biol Med 2009; 27:65-72. [DOI: 10.1080/15368370701878978] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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20
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Markkanen A, Juutilainen J, Naarala J. Pre-exposure to 50 Hz magnetic fields modifies menadione-induced DNA damage response in murine L929 cells. Int J Radiat Biol 2009; 84:742-51. [DOI: 10.1080/09553000802360836] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
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21
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Juutilainen J, Kumlin T, Naarala J. Do extremely low frequency magnetic fields enhance the effects of environmental carcinogens? A meta-analysis of experimental studies. Int J Radiat Biol 2009; 82:1-12. [PMID: 16546898 DOI: 10.1080/09553000600577839] [Citation(s) in RCA: 58] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
PURPOSE This paper is a meta-analysis of data from in vitro studies and short-term animal studies that have combined extremely low frequency magnetic fields with known carcinogens or other toxic physical or chemical agents. MATERIALS AND METHODS The data was analyzed by systematic comparison of study characteristics between positive and negative studies to reveal possible consistent patterns. RESULTS The majority of the studies reviewed were positive, suggesting that magnetic fields do interact with other chemical and physical exposures. Publication bias is unlikely to explain the findings. Interestingly, a nonlinear 'dose-response' was found, showing a minimum percentage of positive studies at fields between 1 and 3 mT. The radical pair mechanism (magnetic field effects on recombination of radical pairs) is a good candidate mechanism for explaining the biphasic dose-response seen in the present analysis. CONCLUSIONS Most of the studies reviewed used magnetic fields of 100 microT or higher, so the findings are not directly relevant for explaining the epidemiological findings suggesting increased risk of childhood leukemia above 0.4 microT. However, confirmed adverse effects even at 100 microT would have implications for risk assessment and management, including the need to reconsider the exposure limits for magnetic fields. There is an obvious need for further studies on combined effects with magnetic fields.
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Affiliation(s)
- Jukka Juutilainen
- University of Kuopio, Department of Environmental Sciences, Kuopio, Finland.
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Santini MT, Ferrante A, Rainaldi G, Indovina P, Indovina PL. Extremely low frequency (ELF) magnetic fields and apoptosis: a review. Int J Radiat Biol 2009; 81:1-11. [PMID: 15962758 DOI: 10.1080/09553000400029502] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
In recent years, there has been increasing evidence that extremely low frequency magnetic fields might be linked to tumours, particularly with childhood leukaemia. In the same period, the role of apoptosis in the tumour process has also gained increasing importance. It is the purpose of this review to describe the apoptotic process, discuss selected papers in which apoptosis is examined in cells exposed to magnetic fields and describe the possible biophysical mechanisms responsible for changes in the apoptotic process in exposed cells. Despite some differences, as a whole, the literature seems to demonstrate that magnetic fields induce changes in apoptosis in cells exposed to different experimental protocols. In addition, the important role of ions, particularly of Ca2+, in the apoptotic process is also discussed, and one possible model for magnetic field action on apoptosis that brings together experimental observations of different nature is suggested and discussed.
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Affiliation(s)
- M T Santini
- Dipartimento di Ematologia, Oncologia e Medicina Molecolare, Istituto Superiore di Sanità, Rome, Italy.
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23
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Sakurai T, Yoshimoto M, Koyama S, Miyakoshi J. Exposure to extremely low frequency magnetic fields affects insulin-secreting cells. Bioelectromagnetics 2008; 29:118-24. [DOI: 10.1002/bem.20370] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
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24
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Dasdag S, Akdag MZ, Ulukaya E, Uzunlar AK, Yegin D. Mobile Phone Exposure Does Not Induce Apoptosis on Spermatogenesis in Rats. Arch Med Res 2008; 39:40-4. [DOI: 10.1016/j.arcmed.2007.06.013] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2007] [Accepted: 06/13/2007] [Indexed: 10/22/2022]
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25
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Farhadi A, Forsyth C, Banan A, Shaikh M, Engen P, Fields JZ, Keshavarzian A. Evidence for non-chemical, non-electrical intercellular signaling in intestinal epithelial cells. Bioelectrochemistry 2007; 71:142-8. [PMID: 17428745 DOI: 10.1016/j.bioelechem.2007.03.001] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2006] [Revised: 02/16/2007] [Accepted: 03/02/2007] [Indexed: 10/23/2022]
Abstract
Synchrony between mechanically separated biological systems is well known. We posed the question: can cells induce synchronous behavior in neighboring cells which are mechanically separated and which cannot communicate via chemical or electrical mechanisms. Caco-2 cell cultures were divided into three groups. "Inducer" cells were exposed to H(2)O(2). "Detector" cells were placed in separate containers near the inducer cells but were not exposed to H(2)O(2). Control cells were exposed to fresh media and were kept in a distant laboratory area. Samples were measured for total protein concentration, NFkappaB activation and structural changes, 10, 30 and 60 min after exposure respectively. Exposing inducer cells to H(2)O(2) resulted in a significant reduction in total protein content (-50%), an increase in nuclear NFkappaB activation (+38%), and structural damage (56%) compared to controls. There was a similar reduction in total protein content (-48%), increase in the nuclear fraction of NFkappaB (+35%) and structural damage (25%) in detector cells. These findings provide evidence in support of a non-chemical, non-electrical communication. This signaling system possibly plays a role in synchronous, stimulus-appropriate cell responses to noxious stimuli and may explain a number of cellular behaviors that are hard to explain based only on conventional cell signaling systems.
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Affiliation(s)
- Ashkan Farhadi
- Section of Gastroenterology and Nutrition, Rush University Medical Center, Chicago, IL 60612, USA.
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26
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Ghibelli L, Cerella C, Cordisco S, Clavarino G, Marazzi S, De Nicola M, Nuccitelli S, D'Alessio M, Magrini A, Bergamaschi A, Guerrisi V, Porfiri LM. NMR exposure sensitizes tumor cells to apoptosis. Apoptosis 2006; 11:359-65. [PMID: 16528477 DOI: 10.1007/s10495-006-4001-1] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
Abstract
NMR technology has dramatically contributed to the revolution of image diagnostic. NMR apparatuses use combinations of microwaves over a homogeneous strong (1 Tesla) static magnetic field. We had previously shown that low intensity (0.3-66 mT) static magnetic fields deeply affect apoptosis in a Ca2+ dependent fashion (Fanelli et al., 1999 FASEBJ., 13;95-102). The rationale of the present study is to examine whether exposure to the static magnetic fields of NMR can affect apoptosis induced on reporter tumor cells of haematopoietic origin. The impressive result was the strong increase (1.8-2.5 fold) of damage-induced apoptosis by NMR. This potentiation is due to cytosolic Ca2+ overload consequent to NMR-promoted Ca2+ influx, since it is prevented by intracellular (BAPTA-AM) and extracellular (EGTA) Ca2+ chelation or by inhibition of plasma membrane L-type Ca2+ channels. Three-days follow up of treated cultures shows that NMR decrease long term cell survival, thus increasing the efficiency of cytocidal treatments. Importantly, mononuclear white blood cells are not sensitised to apoptosis by NMR, showing that NMR may increase the differential cytotoxicity of antitumor drugs on tumor vs normal cells. This strong, differential potentiating effect of NMR on tumor cell apoptosis may have important implications, being in fact a possible adjuvant for antitumor therapies.
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Affiliation(s)
- L Ghibelli
- Dipartimento di Biologia, Universita' di Roma Tor Vergata, Rome, Italy.
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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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Lange S, Viergutz T, Simkó M. Modifications in cell cycle kinetics and in expression of G1 phase-regulating proteins in human amniotic cells after exposure to electromagnetic fields and ionizing radiation. Cell Prolif 2004; 37:337-49. [PMID: 15377333 PMCID: PMC6496295 DOI: 10.1111/j.1365-2184.2004.00317.x] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023] Open
Abstract
Low-frequency electromagnetic fields are suspected of being involved in carcinogenesis, particularly in processes that could be related to cancer promotion. Because development of cancer is associated with deregulated cell growth and we previously observed a magnetic field-induced decrease in DNA synthesis [Lange et al. (2002) Alterations in the cell cycle and in the protein level of cyclin D1p, 21CIP1, and p16INK4a after exposure to 50 HZ. MF in human cells. Radiat. Environ. Biophys.41, 131], this study aims to document the influence of 50 Hz, 1 mT magnetic fields (MF), with or without initial gamma-ionizing radiation (IR), on the following cell proliferation-relevant parameters in human amniotic fluid cells (AFC): cell cycle distribution, expression of the G1 phase-regulating proteins Cdk4, cyclin D1, p21CIP1 and p16INK4a, and Cdk4 activity. While IR induced a G1 delay and a dose-dependent G2 arrest, no discernible changes in cell cycle kinetics were observed due to MF exposure. However, a significant decrease in the protein expression of cyclin D1 and an increase in p21CIP1- and p16INK4a-expression could be detected after exposure to MF alone. IR-exposure caused an augmentation of p21CIP1- and p16INK4a- levels as well, but did not alter cyclin D1 expression. A slight diminution of Cdk4 activity was noticed after MF exposure only, indicating that Cdk4 appears not to act as a mediator of MF- or IR-induced changes in the cell cycle of AFC cells. Co-exposure to MF/IR affected neither cell cycle distribution nor protein expression or kinase activity additionally or synergistically, and therefore MF seems not to modify the mutagenic potency of IR.
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Affiliation(s)
- S Lange
- Research Centre Rossendorf, Institute of Bioinorganic and Radiopharmaceutical Chemistry, Dresden, Germany
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