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Chen C, Chen H, Wang P, Wang X, Wang X, Chen C, Pan W. Reactive Oxygen Species Activate a Ferritin-Linked TRPV4 Channel under a Static Magnetic Field. ACS Chem Biol 2024; 19:1151-1160. [PMID: 38648729 DOI: 10.1021/acschembio.4c00090] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/25/2024]
Abstract
Magnetogenetics has shown great potential for cell function and neuromodulation using heat or force effects under different magnetic fields; however, there is still a contradiction between experimental effects and underlying mechanisms by theoretical computation. In this study, we aimed to investigate the role of reactive oxygen species (ROS) in mechanical force-dependent regulation from a physicochemical perspective. The transient receptor potential vanilloid 4 (TRPV4) cation channels fused to ferritin (T4F) were overexpressed in HEK293T cells and exposed to static magnetic fields (sMF, 1.4-5.0 mT; gradient: 1.62 mT/cm). An elevation of ROS levels was found under sMF in T4F-overexpressing cells, which could lead to lipid oxidation. Compared with the overexpression of TRPV4, ferritin in T4F promoted the generation of ROS under the stimulation of sMF, probably related to the release of iron ions from ferritin. Then, the resulting ROS regulated the opening of the TRPV4 channel, which was attenuated by the direct addition of ROS inhibitors or an iron ion chelator, highlighting a close relationship among iron release, ROS production, and TRPV4 channel activation. Taken together, these findings indicate that the produced ROS under sMF act on the TRPV4 channel, regulating the influx of calcium ions. The study would provide a scientific basis for the application of magnetic regulation in cellular or neural regulation and disease treatment and contribute to the development of the more sensitive regulatory technology.
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Affiliation(s)
- Changyou Chen
- Beijing Key Laboratory of Bioelectromagnetism, Institute of Electrical Engineering, Chinese Academy of Sciences, Beijing 100190, China
- France-China International Laboratory of Evolution and Development of Magnetotactic Multicellular Organisms, Beijing 100190, China
| | - Haitao Chen
- Beijing Key Laboratory of Bioelectromagnetism, Institute of Electrical Engineering, Chinese Academy of Sciences, Beijing 100190, China
- France-China International Laboratory of Evolution and Development of Magnetotactic Multicellular Organisms, Beijing 100190, China
| | - Pingping Wang
- Beijing Key Laboratory of Bioelectromagnetism, Institute of Electrical Engineering, Chinese Academy of Sciences, Beijing 100190, China
- France-China International Laboratory of Evolution and Development of Magnetotactic Multicellular Organisms, Beijing 100190, China
| | - Xue Wang
- Beijing Key Laboratory of Bioelectromagnetism, Institute of Electrical Engineering, Chinese Academy of Sciences, Beijing 100190, China
- France-China International Laboratory of Evolution and Development of Magnetotactic Multicellular Organisms, Beijing 100190, China
- University of the Chinese Academy of Sciences, Beijing 100049, China
| | - Xuting Wang
- Beijing Key Laboratory of Bioelectromagnetism, Institute of Electrical Engineering, Chinese Academy of Sciences, Beijing 100190, China
- France-China International Laboratory of Evolution and Development of Magnetotactic Multicellular Organisms, Beijing 100190, China
- University of the Chinese Academy of Sciences, Beijing 100049, China
| | - Chuanfang Chen
- Beijing Key Laboratory of Bioelectromagnetism, Institute of Electrical Engineering, Chinese Academy of Sciences, Beijing 100190, China
- France-China International Laboratory of Evolution and Development of Magnetotactic Multicellular Organisms, Beijing 100190, China
| | - Weidong Pan
- Beijing Key Laboratory of Bioelectromagnetism, Institute of Electrical Engineering, Chinese Academy of Sciences, Beijing 100190, China
- France-China International Laboratory of Evolution and Development of Magnetotactic Multicellular Organisms, Beijing 100190, China
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Intermittent ELF-MF Induce an Amplitude-Window Effect on Umbilical Cord Blood Lymphocytes. Int J Mol Sci 2022; 23:ijms232214391. [PMID: 36430865 PMCID: PMC9699011 DOI: 10.3390/ijms232214391] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2022] [Revised: 11/15/2022] [Accepted: 11/17/2022] [Indexed: 11/22/2022] Open
Abstract
In a previous study of the effects of intermittent extremely low frequency (ELF) magnetic fields (MF) on umbilical cord blood lymphocytes (UCBL), we evaluated MF amplitudes between 6 µT and 24 µT and found an effect only for those below 13 µT. This suggested the existence of an amplitude window. In this brief communication, we further tested this hypothesis. UCBLs from healthy newborns were isolated and exposed for 72 h to an intermittent ELF-MF (triangular, 7.8 Hz, 250 s ON/250 s OFF) with 6 different amplitudes between 3 µT and 12 µT, utilizing an oblong coil. Percentage of viable, early apoptotic (EA), and late apoptotic/necrotic (LAN) cells were determined by flow cytometry. Moreover, reactive oxygen species (ROS) were determined at 1 h and 3 h of the exposure. Like in our previous work, neither EA, nor LAN, nor ROS were statistically significantly affected by the intermittent ELF-MF. However, the percentage of viable cells was decreased by exposure to the fields with intensities of 6.5 µT and 12 µT (p < 0.05; and p = 0.057 for 8.5 µT). ELF-MF decreased the percentage of viable cells for fields down to 6.5 µT, but not for 5 µT, 4 µT, or 3 µT. Combined with our previous findings, the results reported here indicate an amplitude window effect between 6 µT and 13 µT. The obtained data are in line with a notion of amplitude and frequency windows, which request scanning of both amplitude and frequency while studying the ELF-MF effects.
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Markovic L, Wagner B, Crevenna R. Effects of pulsed electromagnetic field therapy on outcomes associated with osteoarthritis : A systematic review of systematic reviews. Wien Klin Wochenschr 2022; 134:425-433. [PMID: 35362792 PMCID: PMC9213303 DOI: 10.1007/s00508-022-02020-3] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2021] [Accepted: 02/23/2022] [Indexed: 11/30/2022]
Abstract
Background Osteoarthritis (OA) is a chronic degenerative disease of multiple joints with a rising prevalence. Pulsed electromagnetic field (PEMF) therapy may provide a cost-effective, noninvasive, and safe therapeutic modality with growing popularity and use in physical medicine and rehabilitation. The purpose of this study was to synthesize the current knowledge on the use of PEMF in OA. Methods A systematic review of systematic reviews was performed. The PubMed, Embase, PEDro and Web of Science databases were searched based on a predetermined protocol. Results Overall, 69 studies were identified. After removing the duplicates and then screening title, abstract and full text, 10 studies were included in the final analysis. All studies focused on knee OA, and four studies also reported on cervical, two on hand, and one on ankle OA. In terms of the level of evidence and bias, most studies were of low or medium quality. Most concurrence was observed for pain reduction, with other endpoints such as stiffness or physical function showing a greater variability in outcomes. Conclusion The PEMF therapy appears to be effective in the short term to relieve pain and improve function in patients with OA. The existing studies used very heterogeneous treatment schemes, mostly with low sample sizes and suboptimal study designs, from which no sufficient proof of efficacy can be derived. A catalogue of measures to improve the quality of future studies has been drawn up.
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Affiliation(s)
- Lovro Markovic
- Department of Physical Medicine, Rehabilitation and Occupational Medicine, Medical University of Vienna, Waehringer Guertel 18–20, 1090 Vienna, Austria
| | - Barbara Wagner
- Department of Physical Medicine, Rehabilitation and Occupational Medicine, Medical University of Vienna, Waehringer Guertel 18–20, 1090 Vienna, Austria
| | - Richard Crevenna
- Department of Physical Medicine, Rehabilitation and Occupational Medicine, Medical University of Vienna, Waehringer Guertel 18–20, 1090 Vienna, Austria
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Barati M, Darvishi B, Javidi MA, Mohammadian A, Shariatpanahi SP, Eisavand MR, Madjid Ansari A. Cellular stress response to extremely low-frequency electromagnetic fields (ELF-EMF): An explanation for controversial effects of ELF-EMF on apoptosis. Cell Prolif 2021; 54:e13154. [PMID: 34741480 PMCID: PMC8666288 DOI: 10.1111/cpr.13154] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2021] [Revised: 09/21/2021] [Accepted: 10/12/2021] [Indexed: 12/12/2022] Open
Abstract
Impaired apoptosis is one of the hallmarks of cancer, and almost all of the non‐surgical approaches of eradicating tumour cells somehow promote induction of apoptosis. Indeed, numerous studies have stated that non‐ionizing non‐thermal extremely low‐frequency magnetic fields (ELF‐MF) can modulate the induction of apoptosis in exposed cells; however, much controversy exists in observations. When cells are exposed to ELF‐EMF alone, very low or no statistically significant changes in apoptosis are observed. Contrarily, exposure to ELF‐EMF in the presence of a co‐stressor, including a chemotherapeutic agent or ionizing radiation, can either potentiate or inhibit apoptotic effects of the co‐stressor. In our idea, the main point neglected in interpreting these discrepancies is “the cellular stress responses” of cells following ELF‐EMF exposure and its interplay with apoptosis. The main purpose of the current review was to outline the triangle of ELF‐EMF, the cellular stress response of cells and apoptosis and to interpret and unify discrepancies in results based on it. Therefore, initially, we will describe studies performed on identifying the effect of ELF‐EMF on induction/inhibition of apoptosis and enumerate proposed pathways through which ELF‐EMF exposure may affect apoptosis; then, we will explain cellular stress response and cues for its induction in response to ELF‐EMF exposure; and finally, we will explain why such controversies have been observed by different investigators.
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Affiliation(s)
- Mojdeh Barati
- Integrative Oncology Department, Breast Cancer Research Center, Motamed Cancer Institute, ACECR, Tehran, Iran
| | - Behrad Darvishi
- Recombinant Proteins Department, Breast Cancer Research Center, Motamed Cancer Institute, ACECR, Tehran, Iran
| | - Mohammad Amin Javidi
- Integrative Oncology Department, Breast Cancer Research Center, Motamed Cancer Institute, ACECR, Tehran, Iran
| | - Ali Mohammadian
- Department of Medical Biotechnology, Faculty of Medical Sciences, Tarbiat Modares University, Tehran, Iran
| | | | - Mohammad Reza Eisavand
- Recombinant Proteins Department, Breast Cancer Research Center, Motamed Cancer Institute, ACECR, Tehran, Iran
| | - Alireza Madjid Ansari
- Integrative Oncology Department, Breast Cancer Research Center, Motamed Cancer Institute, ACECR, Tehran, Iran
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The protective role of spermine against male reproductive aberrations induced by exposure to electromagnetic field – An experimental investigation in the rat. Toxicol Appl Pharmacol 2019; 370:117-130. [DOI: 10.1016/j.taap.2019.03.009] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2018] [Revised: 02/25/2019] [Accepted: 03/12/2019] [Indexed: 12/15/2022]
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Azadian E, Arjmand B, Khodaii Z, Ardeshirylajimi A. A comprehensive overview on utilizing electromagnetic fields in bone regenerative medicine. Electromagn Biol Med 2019; 38:1-20. [PMID: 30661411 DOI: 10.1080/15368378.2019.1567527] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Stem cells are one of the most important sources to develope a new strategy for repairing bone lesions through tissue engineering. Osteogenic differentiation of stem cells can be affected by various factors such as biological, chemical, physiological, and physical ones. The application of ELF-EMFs has been the subject of many research in bone tissue engineering and evidence suggests that this exogenous physical stimulus can promote osteogenic differentiation in several types of cells. The purpose of this paper is to review the current knowledge on the effects of EMFs on stem cells in bone tissue engineering studies. We recapitulated and analyzed 39 articles that were focused on the application of EMFs for bone tissue engineering purposes. We tabulated scattered information from these articles for easy use and tried to provide an overview of conducted research and identify the knowledge gaps in the field.
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Affiliation(s)
- Esmaeel Azadian
- a Urogenital Stem Cell Research Center , Shahid Beheshti University of Medical Sciences , Tehran , Iran.,b Department of Tissue Engineering and Applied Cell Sciences, School of Advanced Technologies in Medicine , Shahid Beheshti University of Medical Sciences , Tehran , Iran
| | - Bahar Arjmand
- a Urogenital Stem Cell Research Center , Shahid Beheshti University of Medical Sciences , Tehran , Iran.,b Department of Tissue Engineering and Applied Cell Sciences, School of Advanced Technologies in Medicine , Shahid Beheshti University of Medical Sciences , Tehran , Iran
| | - Zohreh Khodaii
- c Dietary supplements and Probiotics research center , Alborz University of Medical Sciences , Karaj , Iran.,d Department of Biochemistry, Genetics and Nutrition, Faculty of Medicine , Alborz University of Medical Sciences , Karaj , Iran
| | - Abdolreza Ardeshirylajimi
- a Urogenital Stem Cell Research Center , Shahid Beheshti University of Medical Sciences , Tehran , Iran.,b Department of Tissue Engineering and Applied Cell Sciences, School of Advanced Technologies in Medicine , Shahid Beheshti University of Medical Sciences , Tehran , Iran
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Van Huizen AV, Morton JM, Kinsey LJ, Von Kannon DG, Saad MA, Birkholz TR, Czajka JM, Cyrus J, Barnes FS, Beane WS. Weak magnetic fields alter stem cell-mediated growth. SCIENCE ADVANCES 2019; 5:eaau7201. [PMID: 30729158 PMCID: PMC6353618 DOI: 10.1126/sciadv.aau7201] [Citation(s) in RCA: 67] [Impact Index Per Article: 13.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/09/2018] [Accepted: 12/17/2018] [Indexed: 05/28/2023]
Abstract
Biological systems are constantly exposed to electromagnetic fields (EMFs) in the form of natural geomagnetic fields and EMFs emitted from technology. While strong magnetic fields are known to change chemical reaction rates and free radical concentrations, the debate remains about whether static weak magnetic fields (WMFs; <1 mT) also produce biological effects. Using the planarian regeneration model, we show that WMFs altered stem cell proliferation and subsequent differentiation via changes in reactive oxygen species (ROS) accumulation and downstream heat shock protein 70 (Hsp70) expression. These data reveal that on the basis of field strength, WMF exposure can increase or decrease new tissue formation in vivo, suggesting WMFs as a potential therapeutic tool to manipulate mitotic activity.
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Affiliation(s)
- Alanna V. Van Huizen
- Department of Biological Sciences, Western Michigan University, Kalamazoo, MI 49008, USA
| | - Jacob M. Morton
- Department of Biological Sciences, Western Michigan University, Kalamazoo, MI 49008, USA
| | - Luke J. Kinsey
- Department of Biological Sciences, Western Michigan University, Kalamazoo, MI 49008, USA
| | - Donald G. Von Kannon
- Department of Biological Sciences, Western Michigan University, Kalamazoo, MI 49008, USA
| | - Marwa A. Saad
- Department of Biological Sciences, Western Michigan University, Kalamazoo, MI 49008, USA
| | - Taylor R. Birkholz
- Department of Biological Sciences, Western Michigan University, Kalamazoo, MI 49008, USA
| | - Jordan M. Czajka
- Department of Biological Sciences, Western Michigan University, Kalamazoo, MI 49008, USA
| | - Julian Cyrus
- Department of Electrical, Computer, and Energy Engineering, University of Colorado Boulder, Boulder, CO 80309, USA
| | - Frank S. Barnes
- Department of Electrical, Computer, and Energy Engineering, University of Colorado Boulder, Boulder, CO 80309, USA
| | - Wendy S. Beane
- Department of Biological Sciences, Western Michigan University, Kalamazoo, MI 49008, USA
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Wu Z, Ding X, Lei G, Zeng C, Wei J, Li J, Li H, Yang T, Cui Y, Xiong Y, Wang Y, Xie D. Efficacy and safety of the pulsed electromagnetic field in osteoarthritis: a meta-analysis. BMJ Open 2018; 8:e022879. [PMID: 30552258 PMCID: PMC6303578 DOI: 10.1136/bmjopen-2018-022879] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/18/2018] [Revised: 07/21/2018] [Accepted: 10/19/2018] [Indexed: 12/20/2022] Open
Abstract
OBJECTIVE To investigate the efficacy and safety of the pulsed electromagnetic field (PEMF) therapy in treating osteoarthritis (OA). DESIGN Meta-analysis. DATA SOURCES PubMed, Embase, the Cochrane Library and Web of Science were searched through 13 October 2017. ELIGIBILITY CRITERIA FOR SELECTING STUDIES Randomised controlled trials compared the efficacy of PEMF therapy with sham control in patients with OA. DATA EXTRACTION AND SYNTHESIS Pain, function, adverse effects and characteristics of participants were extracted. RevMan V.5.2 was used to perform statistical analyses. RESULTS Twelve trials were included, among which ten trials involved knee OA, two involved cervical OA and one involved hand OA. The PEMF group showed more significant pain alleviation than the sham group in knee OA (standardised mean differences (SMD)=-0.54, 95% CI -1.04 to -0.04, p=0.03) and hand OA (SMD=-2.85, 95% CI -3.65 to -2.04, p<0.00001), but not in cervical OA. Similarly, comparing with the sham-control treatment, significant function improvement was observed in the PEMF group in both knee and hand OA patients (SMD=-0.34, 95% CI -0.53 to -0.14, p=0.0006, and SMD=-1.49, 95% CI -2.12 to -0.86, p<0.00001, respectively), but not in patients with cervical OA. Sensitivity analyses suggested that the exposure duration <=30 min per session exhibited better effects compared with the exposure duration >30 min per session. Three trials reported adverse events, and the combined results showed that there was no significant difference between PEMF and the sham group. CONCLUSIONS PEMF could alleviate pain and improve physical function for patients with knee and hand OA, but not for patients with cervical OA. Meanwhile, a short PEMF treatment duration (within 30 min) may achieve more favourable efficacy. However, given the limited number of study available in hand and cervical OA, the implication of this conclusion should be cautious for hand and cervical OA.
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Affiliation(s)
- Ziying Wu
- Department of Orthopaedics, Xiangya Hospital, Central South University, Changsha, Hunan Province, China
| | - Xiang Ding
- Department of Orthopaedics, Xiangya Hospital, Central South University, Changsha, Hunan Province, China
| | - Guanghua Lei
- Department of Orthopaedics, Xiangya Hospital, Central South University, Changsha, Hunan Province, China
| | - Chao Zeng
- Department of Orthopaedics, Xiangya Hospital, Central South University, Changsha, Hunan Province, China
| | - Jie Wei
- Department of Health Management Center, Xiangya Hospital, Central South University, Changsha, Hunan Province, China
- Department of Epidemiology and Health Statistics, Xiangya School of Public Health, Central South University, Changsha, Hunan Province, China
| | - Jiatian Li
- Department of Orthopaedics, Xiangya Hospital, Central South University, Changsha, Hunan Province, China
| | - Hui Li
- Department of Orthopaedics, Xiangya Hospital, Central South University, Changsha, Hunan Province, China
| | - Tuo Yang
- Department of Health Management Center, Xiangya Hospital, Central South University, Changsha, Hunan Province, China
| | - Yang Cui
- International Medical Department, Xiangya Hospital, Central South University, Changsha, Hunan Province, China
| | - Yilin Xiong
- Department of Orthopaedics, Xiangya Hospital, Central South University, Changsha, Hunan Province, China
| | - Yilun Wang
- Department of Orthopaedics, Xiangya Hospital, Central South University, Changsha, Hunan Province, China
| | - Dongxing Xie
- Department of Orthopaedics, Xiangya Hospital, Central South University, Changsha, Hunan Province, China
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Kumar S, Dey S, Jain S. Extremely low-frequency electromagnetic fields: A possible non-invasive therapeutic tool for spinal cord injury rehabilitation. Electromagn Biol Med 2016; 36:88-101. [PMID: 27399648 DOI: 10.1080/15368378.2016.1194290] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Abstract
Traumatic insults to the spinal cord induce both immediate mechanical damage and subsequent tissue degeneration. The latter involves a range of events namely cellular disturbance, homeostatic imbalance, ionic and neurotransmitters derangement that ultimately result in loss of sensorimotor functions. The targets for improving function after spinal cord injury (SCI) are mainly directed toward limiting these secondary injury events. Extremely low-frequency electromagnetic field (ELF-EMF) is a possible non-invasive therapeutic intervention for SCI rehabilitation which has the potential to constrain the secondary injury-induced events. In the present review, we discuss the effects of ELF-EMF on experimental and clinical SCI as well as on biological system.
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Affiliation(s)
- Suneel Kumar
- a Department of Physiology , All India Institute of Medical Sciences , New Delhi , India.,b W. M. Keck Center for Collaborative Neuroscience, Rutgers, The State University of New Jersey , Piscataway , NJ , USA
| | - Soumil Dey
- a Department of Physiology , All India Institute of Medical Sciences , New Delhi , India
| | - Suman Jain
- a Department of Physiology , All India Institute of Medical Sciences , New Delhi , India
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Bistolfi F. Extremely Low-Frequency Pulsed Magnetic Fields and Multiple Sclerosis: Effects on Neurotransmission Alone or Also on Immunomodulation? Building a Working Hypothesis. Neuroradiol J 2016; 20:676-93. [DOI: 10.1177/197140090702000612] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2007] [Accepted: 09/17/2007] [Indexed: 11/15/2022] Open
Abstract
This paper outlines the current state of knowledge on the pathology and treatment of multiple sclerosis (MS) and critically analyses the vast clinical experience of Sandyk in the use of pulsed magnetic fields of 5 Hz at 7.5 pT to treat many symptoms of MS. A complete regression of symptoms, or at least a major improvement, is sometimes so rapid as to suggest that ELF fields exert a greater effect on axonal and synaptic neurotransmission than on the processes leading to demyelination. Pulsed magnetic fields of 50–100 Hz and a few mT (whose flux intensity is 109 times greater than that of the fields used by Sandyk) have been seen to induce profound morphological changes (the Marinozzi effect) in the plasma membrane of several cell types, including Raji human lymphoblastoid cells. These observations underlie the author's hypothesis on the possible use of such fields in the treatment of MS. Indeed, these fields should induce the functional arrest of the cells (B- and T-lymphocytes, macrophages, microglia, dendritic cells) of the MS plaque, thereby providing an ‘electromagnetic immunomodulatory boost’ to the effects of drug therapy. To test this working hypothesis, it is suggested that preliminary experimental research be carried out to ascertain: 1) the Marinozzi effect in vivo; 2) the Marinozzi effect on microglia and dendritic cells; and 3) the duration of the membrane changes and their relaxation rate. ELF magnetic fields in the picotesla and millitesla ranges are aimed at improving neurotransmission and correcting local immune pathology, respectively. Both types of field might find application in the treatment of MS patients who no longer respond to or tolerate currently used drugs.
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Affiliation(s)
- F. Bistolfi
- Radiotherapy Department, Galliera Hospital, Genoa, Italy
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Effects of electromagnetic fields exposure on plasma hormonal and inflammatory pathway biomarkers in male workers of a power plant. Int Arch Occup Environ Health 2015; 89:33-42. [DOI: 10.1007/s00420-015-1049-7] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2014] [Accepted: 03/16/2015] [Indexed: 11/25/2022]
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12
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Manzella N, Bracci M, Ciarapica V, Staffolani S, Strafella E, Rapisarda V, Valentino M, Amati M, Copertaro A, Santarelli L. Circadian gene expression and extremely low-frequency magnetic fields: an in vitro study. Bioelectromagnetics 2015; 36:294-301. [PMID: 25808738 DOI: 10.1002/bem.21915] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2013] [Accepted: 03/06/2015] [Indexed: 12/31/2022]
Abstract
It is well known that circadian clocks are mainly regulated by light targeting signaling pathways in the hypothalamic suprachiasmatic nucleus. However, an entrainment mediated by non-photic sensory stimuli was also suggested for peripheral clocks. Exposure to extremely low frequency (ELF) electromagnetic fields might affect circadian rhythmicity. The goal of this research was to investigate effects of ELF magnetic fields (ELF-MF) on circadian clock genes in a human fibroblast cell line. We found that an ELF-MF (0.1 mT, 50 Hz) exposure was capable of entraining expression of clock genes BMAL1, PER2, PER3, CRY1, and CRY2. Moreover, ELF-MF treatment induced an alteration in circadian clock gene expression previously entrained by serum shock stimulation. These results support the hypothesis that ELF-MF may be able to drive circadian physiologic processes by modulating peripheral clock gene expression.
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Affiliation(s)
- Nicola Manzella
- Occupational Medicine, Department of Clinical and Molecular Sciences, Polytechnic University of Marche, Ancona, Italy
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Selim A, Zayed M, Zayed M. Magnetic field treated water effects on germination, growth and physio-chemical aspects of some economic plants. ACTA ACUST UNITED AC 2013. [DOI: 10.1556/abot.55.2013.1-2.7] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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Jouni FJ, Abdolmaleki P, Ghanati F. Oxidative stress in broad bean (Vicia faba L.) induced by static magnetic field under natural radioactivity. Mutat Res 2011; 741:116-21. [PMID: 22108253 DOI: 10.1016/j.mrgentox.2011.11.003] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2011] [Revised: 04/26/2011] [Accepted: 11/08/2011] [Indexed: 10/15/2022]
Abstract
The investigation was performed to evaluate the influence of the static magnetic field on oxidative stress in Vicia faba cultivated in soil from high background natural radioactivity in Iran. Soil samples were collected from Ramsar, Iran where the annual radiation absorbed dose from background radiation is substantially higher than 20 mSv/year. The soil samples were then divided into 2 separate groups including high and low natural radioactivity. The plants were continuously exposed to static magnetic field of 15 mT for 8 days, each 8h/day. The results showed that in the plants cultivated in soils with high background natural radioactivity and low background natural radioactivity the activity of antioxidant enzymes as well as flavonoid content were lower than those of the control. Treatment of plants with static magnetic field showed similar results in terms of lowering of antioxidant defense system and increase of peroxidation of membrane lipids. Accumulation of ROS also resulted in chromosomal aberration and DNA damage. This phenomenon was more pronounced when a combination of natural radiation and treatment with static magnetic field was applied. The results suggest that exposure to static magnetic field causes accumulation of reactive oxygen species in V. faba and natural radioactivity of soil exaggerates oxidative stress.
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Affiliation(s)
- Fatemeh Javani Jouni
- Department of Biophysics, Faculty of Biological Science, Tarbiat Modares Univ., POB: 14115-154, Tehran, Iran
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Ballardin M, Tusa I, Fontana N, Monorchio A, Pelletti C, Rogovich A, Barale R, Scarpato R. Non-thermal effects of 2.45 GHz microwaves on spindle assembly, mitotic cells and viability of Chinese hamster V-79 cells. Mutat Res 2011; 716:1-9. [PMID: 21827772 DOI: 10.1016/j.mrfmmm.2011.07.009] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2010] [Revised: 07/15/2011] [Accepted: 07/22/2011] [Indexed: 05/31/2023]
Abstract
The production of mitotic spindle disturbances and activation of the apoptosis pathway in V79 Chinese hamster cells by continuous 2.45 GHz microwaves exposure were studied, in order to investigate possible non-thermal cell damage. We demonstrated that microwave (MW) exposure at the water resonance frequency was able to induce alteration of the mitotic apparatus and apoptosis as a function of the applied power densities (5 and 10mW/cm(2)), together with a moderate reduction in the rate of cell division. After an exposure time of 15 min the proportion of aberrant spindles and of apoptotic cells was significantly increased, while the mitotic index decreased as well, as compared to the untreated V79 cells. Additionally, in order to understand if the observed effects were due to RF exposure per se or to a thermal effect, V79 cells were also treated in thermostatic bath mimicking the same temperature increase recorded during microwave emission. The effect of temperature on the correct assembly of mitotic spindles was negligible up to 41°C, while apoptosis was induced only when the medium temperature achieved 40°C, thus exceeding the maximum value registered during MW exposure. We hypothesise that short-time MW exposures at the water resonance frequency cause, in V79 cells, reversible alterations of the mitotic spindle, this representing, in turn, a pro-apoptotic signal for the cell line.
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Wang T, Nie Y, Zhao S, Han Y, Du Y, Hou Y. Involvement of midkine expression in the inhibitory effects of low-frequency magnetic fields on cancer cells. Bioelectromagnetics 2011; 32:443-52. [PMID: 21360556 DOI: 10.1002/bem.20654] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2010] [Accepted: 01/15/2011] [Indexed: 11/07/2022]
Abstract
Effects of magnetic fields (MFs) on cancer cells may depend on cell type and exposure conditions. Gene expression levels are different among cancer cells. However, the effect of MFs on cancer cells with different gene expressions is still unclear. In this study, the cancer cell lines BGC-823, MKN-45, MKN-28, A549, SPC-A1, and LOVO were exposed to a low-frequency MF. Specific parameters of MFs were determined. Furthermore, the potential of the MF to influence cancer cell growth with midkine (MK) expression was evaluated. Cell proliferation and cell cycle were detected using the CCK-8 assay and flow cytometry. Cell ultrastructure was observed by transmission electron microscopy. BGC-823 cells with over-expression of MK (BGC-MK cells) and stanniocalcin-1 were generated by plasmid construction and transfection. Results showed that exposure to a 0.4-T, 7.5 Hz MF inhibited the proliferation of BGC-823, MKN-28, A549, and LOVO cells, but not MKN-45 and SPC-A1 cells. Moreover, the inhibitory effect of the MF on BGC-MK cells was lower (12.3%) than that of BGC-823 cells (20.3%). Analysis of the cell cycle showed that exposure to the MF led to a significant increase in the S phase in BGC-823 cells, but not in BGC-MK cells. In addition, organelle morphology was modified in BGC-823 cells exposed to the MF. These results suggest that exposure to a 0.4-T, 7.5 Hz MF could inhibit tumor cell proliferation and disturb the cell cycle. The alteration of MK expression in cancer cells may be related to the inhibitory effect of the MF on these cells.
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Affiliation(s)
- Tingting Wang
- Immunology and Reproduction Biology Lab, Medical School and State Key Laboratory of Pharmaceutical Biotechnology, Nanjing University, Nanjing, China
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Ayşe IG, Zafer A, Sule O, Işil IT, Kalkan T. Differentiation of K562 cells under ELF-EMF applied at different time courses. Electromagn Biol Med 2011; 29:122-30. [PMID: 20707646 DOI: 10.3109/15368378.2010.502451] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
The time-course of ELF-EMF application to biological systems is thought to be an important parameter determining the physiological outcome. This study investigated the effect of ELF-EMF on the differentiation of K562 cells at different time courses. ELF-EMF (50 Hz, 5 mT, 1 h) was applied at two different time-courses; first at the onset of hemin induction for 1 h, and second, daily 1 h for four days. While single exposure to ELF-EMF resulted in a decrease in differentiation, ELF-EMF applied everyday for 1 h caused an increase in differentiation. The effect of co-stressors, magnesium, and heat-shock was also determined and similar results were obtained. ELF-EMF increased ROS levels in K562 cells not treated with hemin, however did not change ROS levels of hemin treated cells indicating that ROS was not the cause. Overall, these results imply that the time-course of application is an important parameter determining the physiological response of cells to ELF-EMF.
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Affiliation(s)
- Inhan-Garip Ayşe
- Department of Biophysics, Marmara University School of Medicine, Istanbul, Turkey.
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Bekhite MM, Finkensieper A, Abou-Zaid FA, El-Shourbagy IK, Omar KM, Figulla HR, Sauer H, Wartenberg M. Static electromagnetic fields induce vasculogenesis and chondro-osteogenesis of mouse embryonic stem cells by reactive oxygen species-mediated up-regulation of vascular endothelial growth factor. Stem Cells Dev 2010; 19:731-43. [PMID: 19788349 DOI: 10.1089/scd.2008.0266] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023] Open
Abstract
Electromagnetic fields (EMFs) are used to treat bone diseases. Herein, the effects of static EMFs on chondroosteogenesis and vasculogenesis of embryonic stem (ES) cells and bone mineralization of mouse fetuses were investigated. Treatment of differentiating ES cells with static EMFs (0.4-2 mT) stimulated vasculogenesis and chondro-osteogenesis and increased reactive oxygen species (ROS), which was abolished by the free radical scavengers trolox, 1,10-phenanthroline (phen), and the NAD(P)H oxidase inhibitor diphenylen iodonium (DPI). In contrast, EMFs of 10 mT field strength exerted inhibitory effects on vasculogenesis and chondro-osteogenesis despite robust ROS generation. EMFs of 1 mT and 10 mT increased and decreased vascular endothelial growth factor (VEGF) expression, respectively, which was abolished by DPI and radical scavengers. EMFs activated extracellular-regulated kinase 1/2 (ERK1/2), p38, and c-jun N-terminal kinase (JNK), which was sensitive to DPI treatment. The increase in VEGF by EMFs was inhibited by the ERK1/2 inhibitor U0126 but not by SB203580 and SP600125, which are p38 and JNK inhibitors, respectively, suggesting VEGF regulation by ERK1/2. Chondroosteogenesis and vasculogenesis of ES cells was blunted by trolox, DPI, and the VEGF receptor-2 (flk-1) antagonist SU5614. In mouse fetuses 1 mT EMFs increased and 10 mT EMFs decreased bone mineralization, which was abolished in the presence of trolox. Hence, EMFs induced chondro-osteogenesis and vasculogenesis in ES cells and bone mineralization of mouse fetuses by a ROS-dependent up-regulation of VEGF expression.
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Affiliation(s)
- Mohamed M Bekhite
- Department of Internal Medicine I, Cardiology Division, Friedrich Schiller University Jena, Germany
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Martiny K, Lunde M, Bech P. Transcranial low voltage pulsed electromagnetic fields in patients with treatment-resistant depression. Biol Psychiatry 2010; 68:163-9. [PMID: 20385376 DOI: 10.1016/j.biopsych.2010.02.017] [Citation(s) in RCA: 86] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/14/2009] [Revised: 02/16/2010] [Accepted: 02/20/2010] [Indexed: 11/30/2022]
Abstract
BACKGROUND Approximately 30% of patients with depression are resistant to antidepressant drugs. Repetitive transcranial magnetic stimulation (rTMS) has been found effective in combination with antidepressants in this patient group. The aim of this study was to evaluate the antidepressant effect of a new principle using low-intensity transcranially applied pulsed electromagnetic fields (T-PEMF) in combination with antidepressants in patients with treatment-resistant depression. METHODS This was a sham-controlled double-blind study comparing 5 weeks of active or sham T-PEMF in patients with treatment-resistant major depression. The antidepressant treatment, to which patients had been resistant, was unchanged 4 weeks before and during the study period. Weekly assessments were performed using both clinician-rated and patient-rated scales. The T-PEMF equipment was designed as a helmet containing seven separate coils located over the skull that generated an electrical field in tissue with orders of magnitude weaker than those generated by rTMS equipment. RESULTS Patients on active T-PEMF showed a clinically and statistically significant better outcome than patients treated with sham T-PEMF, with an onset of action within the first weeks of therapy. Effect size on the Hamilton 17-item Depression Rating Scale was .62 (95% confidence interval .21-1.02). Treatment-emergent side effects were few and mild. CONCLUSION The T-PEMF treatment was superior to sham treatment in patients with treatment-resistant depression. Few side effects were observed. Mechanism of the antidepressant action, in light of the known effects of PEMF stimulation to the brain, is discussed.
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Affiliation(s)
- Klaus Martiny
- Psychiatric Research Unit, Mental Health Center North Zealand, Hillerød, Denmark.
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20
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Exposure to ELF magnetic fields modulate redox related protein expression in mouse macrophages. Toxicol Lett 2010; 192:330-6. [DOI: 10.1016/j.toxlet.2009.11.010] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2009] [Revised: 10/24/2009] [Accepted: 11/04/2009] [Indexed: 11/20/2022]
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22
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Chiang H, Li CM, Fu YD, Lu DJ. The Mechanism of Suppression of GAP Junctional Intercellular Communication by 50-Hz Magnetic Fields. ACTA ACUST UNITED AC 2009. [DOI: 10.3109/15368379909022580] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
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Li CM, Chiang H, Fu YD, Lu DQ, Shao J. Exposure to 50-HZ Electromagnetic Fields: Effects of Time and Field Strength on GAP Junctional Intercellular Communications. ACTA ACUST UNITED AC 2009. [DOI: 10.3109/15368379909022581] [Citation(s) in RCA: 6] [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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Sun WJ, Chiang H, Fu YT, Yu YN, Xie HY, Lu DQ. EXPOSURE TO 50 HZ ELECTROMAGNETIC FIELDS INDUCES THE PHOSPHORYLATION AND ACTIVITY OF STRESS-ACTIVATED PROTEIN KINASE IN CULTURED CELLS. ACTA ACUST UNITED AC 2009. [DOI: 10.1081/jbc-100108579] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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25
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Ke XQ, Sun WJ, Lu DQ, Fu YT, Chiang H. 50-Hz magnetic field induces EGF-receptor clustering and activates RAS. Int J Radiat Biol 2008; 84:413-20. [PMID: 18464070 DOI: 10.1080/09553000801998875] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
Abstract
PURPOSE In a previous study, we found that exposure to a 50 Hz magnetic field (MF) could activate stress-activated protein kinase (SAPK) and P38 mitogen-activated protein (MAP) kinase (P38 MAPK) in Chinese hamster lung (CHL) fibroblast cells, and simultaneous exposure to a 'noise' MF of the same intensity inhibited these effects. In order to explore the possible target sites and upstream signal transduction molecules of SAPK and P38 MAPK, and further validate the interference effects of 'noise' MF on 50 Hz MF, the effects of MF exposure on clustering of epidermal growth factor (EGF) receptors and Ras protein activation were investigated. MATERIALS AND METHODS CHL cells were exposed to a 50 Hz sinusoidal MF at 0.4 mT for different durations, and clustering of EGF receptors on cellular membrane and Ras protein activation were analyzed using immunofluorescence confocal microscopy and co-precipitation technology. EGF treatment served as the positive control. RESULTS The results showed that, compared with sham-exposed cells, exposure to a 50 Hz MF at 0.4 mT for 5 min slightly induced EGF receptor clustering, whereas exposure for 15 min enhanced receptor clustering significantly. Corresponding to receptor clustering, Ras protein was also activated after exposure to the 50 Hz MF. Exposure to a 'noise' MF (with frequency ranges from 30 - 90 Hz) at the same intensity and durations, did not significantly affect EGF receptor clustering and Ras protein. However, by superimposing the 'noise' MF, receptor clustering and Ras activation induced by 50 Hz MF were inhibited. CONCLUSION The results suggested that membrane receptors could be one of the most important targets where extremely low frequency (ELF) MF interacts with cells, and Ras may participate in the signal transduction process of 50 Hz MF. Furthermore, a 'noise' MF could inhibit these effects caused by ELF-MF.
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Affiliation(s)
- X Q Ke
- Department of Hygiene of Children and Adolescents, Zhejiang University School of Medicine, Hangzhou, China
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Villarini M, Moretti M, Scassellati-Sforzolini G, Boccioli B, Pasquini R. Effects of co-exposure to extremely low frequency (50 Hz) magnetic fields and xenobiotics determined in vitro by the alkaline comet assay. THE SCIENCE OF THE TOTAL ENVIRONMENT 2006; 361:208-19. [PMID: 15979690 DOI: 10.1016/j.scitotenv.2005.05.006] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/29/2004] [Accepted: 05/09/2005] [Indexed: 05/03/2023]
Abstract
In the present study, we used human peripheral blood leukocytes from 4 different donors, to investigate in vitro the possible genotoxic and/or co-genotoxic activity of extremely low frequency magnetic fields (ELF-MF) at 3 mT intensity. Two model mutagens were used to study the possible interaction between ELF-MF and xenobiotics: N-methyl-N'-nitro-N-nitrosoguanidine (MNNG) and 4-nitroquinoline N-oxide (4NQO). Primary DNA damage was evaluated by the alkaline single-cell microgel-electrophoresis ("comet") assay. Control cells (leukocytes not exposed to ELF-MF, nor treated with genotoxins) from the different blood donors showed a comparable level of basal DNA damage, whereas the contribution of individual susceptibility toward ELF-MF and the tested genotoxic compounds led to differences in the extent of DNA damage observed following exposure to the genotoxins, both in the presence and in the absence of an applied ELF-MF. A 3 mT ELF-MF alone was unable to cause direct primary DNA damage. In leukocytes exposed to ELF-MF and genotoxins, the extent of MNNG-induced DNA damage increased with exposure duration compared to sham-exposed cells. The opposite was observed in cells treated with 4NQO. In this case the extent of 4NQO-induced DNA damage was somewhat reduced in leukocytes exposed to ELF-MF compared to sham-exposed cells. Moreover, in cells exposed to ELF-MF an increased concentration of GSH was always observed, compared to sham-exposed cells. Since following GSH conjugation the genotoxic pattern of MNNG and 4NQO is quite different, an influence of ELF-MF on the activity of the enzyme involved in the synthesis of GSH leading to different activation/deactivation of the model mutagens used was hypothesized to explain the different trends observed in MNNG and 4NQO genotoxic activity in the presence of an applied ELF-MF. The possibility that ELF-MF might interfere with the genotoxic activity of xenobiotics has important implications, since human populations are likely to be exposed to a variety of genotoxic agents concomitantly with exposure to this type of physical agent.
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Affiliation(s)
- Milena Villarini
- Department of Medical-Surgical Specialities and Public Health, University of Perugia, Via del Giochetto, 06126 Perugia, Italy
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Zeng Q, Ke X, Gao X, Fu Y, Lu D, Chiang H, Xu Z. Noise magnetic fields abolish the gap junction intercellular communication suppression induced by 50 hz magnetic fields. Bioelectromagnetics 2006; 27:274-9. [PMID: 16511880 DOI: 10.1002/bem.20207] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
Previously, we have reported that exposure to 50 Hz coherent sinusoidal magnetic fields (MF) for 24 h inhibits gap junction intercellular communication (GJIC) in mammalian cells at an intensity of 0.4 mT and enhances the inhibition effect of 12-O-tetradecanoylphorbol-13-acetate (TPA) at 0.2 mT. In the present study, we further explored the effects of incoherent noise MF on MF-induced GJIC inhibition. GJIC was determined by fluorescence recovery after photobleaching (FRAP) with a laser-scanning confocal microscope. The rate of fluorescence recovery (R) at 10 min after photobleaching was adopted as the functional index of GJIC. The R-value of NIH3T3 cells exposed to 50 Hz sinusoidal MF at 0.4 mT for 24 h was 30.85 +/- 14.70%, while the cells in sham exposure group had an R-value of 46.36 +/- 20.68%, demonstrating that the GJIC of NIH3T3 cells was significantly inhibited by MF exposure (P < .05). However, there were no significant differences in the R-values of the sham exposure, MF-plus-noise MF exposure (R: 49.58 +/- 19.38%), and noise MF exposure groups (R: 46.74 +/- 21.14%) (P > .05), indicating that the superposition of a noise MF alleviated the suppression of GJIC induced by the 50 Hz MF. In addition, although MF at an intensity of 0.2 mT synergistically enhanced TPA-induced GJIC inhibition (R: 24.90 +/- 13.50% vs. 35.82 +/- 17.18%, P < .05), further imposition of a noise MF abolished the synergistic effect of coherent MF (R: 32.51 +/- 18.37%). Overall, the present data clearly showed that although noise MF itself had no effect on GJIC of NIH3T3 cells, its superposition onto a coherent sinusoidal MF at the same intensity abolished MF-induced GJIC suppression. This is the first report showing that noise MF neutralizes 50 Hz MF-induced biological effect by using a signaling component as the test endpoint.
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Affiliation(s)
- Qunli Zeng
- Bioelectromagnetics Laboratory, Zhejiang University School of Medicine, Hangzhou, China
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Kindzelskii AL, Petty HR. Ion channel clustering enhances weak electric field detection by neutrophils: apparent roles of SKF96365-sensitive cation channels and myeloperoxidase trafficking in cellular responses. EUROPEAN BIOPHYSICS JOURNAL: EBJ 2005; 35:1-26. [PMID: 16044273 DOI: 10.1007/s00249-005-0001-2] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/18/2005] [Revised: 05/13/2005] [Accepted: 06/23/2005] [Indexed: 10/25/2022]
Abstract
We have tested Galvanovskis and Sandblom's prediction that ion channel clustering enhances weak electric field detection by cells as well as how the elicited signals couple to metabolic alterations. Electric field application was timed to coincide with certain known intracellular chemical oscillators (phase-matched conditions). Polarized, but not spherical, neutrophils labeled with anti-K(v)1.3, FL-DHP, and anti-TRP1, but not anti-T-type Ca(2+) channels, displayed clusters at the lamellipodium. Resonance energy transfer experiments showed that these channel pairs were in close proximity. Dose-field sensitivity studies of channel blockers suggested that K(+) and Ca(2+) channels participate in field detection, as judged by enhanced oscillatory NAD(P)H amplitudes. Further studies suggested that K(+) channel blockers act by reducing the neutrophil's membrane potential. Mibefradil and SKF93635, which block T-type Ca(2+) channels and SOCs, respectively, affected field detection at appropriate doses. Microfluorometry and high-speed imaging of indo-1-labeled neutrophils was used to examine Ca(2+) signaling. Electric fields enhanced Ca(2+) spike amplitude and triggered formation of a second traveling Ca(2+) wave. Mibefradil blocked Ca(2+) spikes and waves. Although 10 microM SKF96365 mimicked mibefradil, 7 microM SKF96365 specifically inhibited electric field-induced Ca(2+) signals, suggesting that one SKF96365-senstive site is influenced by electric fields. Although cells remained morphologically polarized, ion channel clusters at the lamellipodium and electric field sensitivity were inhibited by methyl-beta-cyclodextrin. As a result of phase-matched electric field application in the presence of ion channel clusters, myeloperoxidase (MPO) was found to traffic to the cell surface. As MPO participates in high amplitude metabolic oscillations, this suggests a link between the signaling apparatus and metabolic changes. Furthermore, electric field effects could be blocked by MPO inhibition or removal while certain electric field effects were mimicked by the addition of MPO to untreated cells. Therefore, channel clustering plays an important role in electric field detection and downstream responses of morphologically polarized neutrophils. In addition to providing new mechanistic insights concerning electric field interactions with cells, our work suggests novel methods to remotely manipulate physiological pathways.
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Affiliation(s)
- Andrei L Kindzelskii
- Department of Ophthalmology and Visual Sciences, The University of Michigan Medical School, 1000 Wall Street, Ann Arbor, MI 48105, USA
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Thamsborg G, Florescu A, Oturai P, Fallentin E, Tritsaris K, Dissing S. Treatment of knee osteoarthritis with pulsed electromagnetic fields: a randomized, double-blind, placebo-controlled study. Osteoarthritis Cartilage 2005; 13:575-81. [PMID: 15979009 DOI: 10.1016/j.joca.2005.02.012] [Citation(s) in RCA: 76] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/22/2004] [Revised: 02/21/2005] [Accepted: 02/21/2005] [Indexed: 02/02/2023]
Abstract
OBJECTIVE The investigation aimed at determining the effectiveness of pulsed electromagnetic fields (PEMF) in the treatment of osteoarthritis (OA) of the knee by conducting a randomized, double-blind, placebo-controlled clinical trial. DESIGN The trial consisted of 2h daily treatment 5 days per week for 6 weeks in 83 patients with knee OA. Patient evaluations were done at baseline and after 2 and 6 weeks of treatment. A follow-up evaluation was done 6 weeks after treatment. Activities of daily living (ADL), pain and stiffness were evaluated using the Western Ontario and McMaster Universities (WOMAC) questionnaire. RESULTS Within group analysis revealed a significant improvement in ADL, stiffness and pain in the PEMF-treated group at all evaluations. In the control group there was no effect on ADL after 2 weeks and a weak significance was seen after 6 and 12 weeks. Significant effects were seen on pain at all evaluations and on stiffness after 6 and 12 weeks. Between group analysis did not reveal significant improvements over time. Analysis of ADL score for the PEMF-treated group revealed a significant correlation between less improvement and increasing age. Analysis of patients <65 years using between group analysis revealed a significant improvement for stiffness on treated knee after 2 weeks, but this effect was not observed for ADL and pain. CONCLUSIONS Applying between group analysis we were unable to demonstrate a beneficial symptomatic effect of PEMF in the treatment of knee OA in all patients. However, in patients <65 years of age there is significant and beneficial effect of treatment related to stiffness.
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Affiliation(s)
- G Thamsborg
- Department of Geriatri and Rheumatology, Glostrup Hospital, 2600 Glostrup, Denmark
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Crumpton MJ. The Bernal Lecture 2004 Are low-frequency electromagnetic fields a health hazard? Philos Trans R Soc Lond B Biol Sci 2005; 360:1223-30. [PMID: 16147518 PMCID: PMC1569497 DOI: 10.1098/rstb.2005.1663] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2004] [Accepted: 01/17/2005] [Indexed: 11/12/2022] Open
Abstract
Electric power is an essential commodity of the developed world, and is critical to the continuing progress of our technology-based society, as well as to the growth of less privileged societies. In contrast to its overwhelming benefits, there is a suspicion that the magnetic component of the electromagnetic fields (EMFs) associated with power distribution and electrical appliances has adverse health effects, especially a small increased incidence of childhood leukaemia. The possibility that environmental EMFs represent a health hazard has serious economic implications for government, the electricity industry and society, as well as raising several profound scientific challenges, including, in particular, biophysical mechanisms, experimental replication and scientific uncertainty. These challenges are explored in relation to the experiences of the EMF Biological Research Trust, a UK medical research charity which funds basic research on the biological effects of extremely low-frequency electromagnetic fields (ELF-EMFs). As judged from these experiences, at the present time there is no compelling experimental evidence that environmental ELF-EMFs induce biological responses.
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Affiliation(s)
- Michael J Crumpton
- Scientific Advisory Committee, The EMF Biological Research Trust, South Croydon, UK.
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Roman A, Zyss T, Nalepa I. Magnetic field inhibits isolated lymphocytes' proliferative response to mitogen stimulation. Bioelectromagnetics 2005; 26:201-6. [PMID: 15768428 DOI: 10.1002/bem.20066] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
We aimed to find out how the exposure of isolated lymphocytes to a pulsed magnetic field (MF) affected their in vitro proliferative response to mitogenic stimulation. Cells were exposed to MF of various intensities (0.3, 0.6, and 1.2 T) at a constant frequency of 30 Hz, for a period of 60, 180, and 330 s. Then, the proliferative response of splenocytes was induced by optimal concentrations of concanavalin A (Con A; mitogenic toward T cells), bacterial lipopolysaccharide (LPS; mitogenic toward B cells), or pokeweed mitogen (PWM; mitogenic toward both populations). We found that the exposure of lymphocytes to the MF profoundly inhibited their proliferative response to mitogens. The suppressive action of the MF on B and T cell proliferation was intensified when a cooperative response of those two lymphocyte populations was simultaneously induced by PWM. The inhibitory effect of MF depended on the exposure time and MF intensity. Prolonged exposure and/or a stronger intensity of the MF weakened its inhibitory influence on the response of lymphocyte to mitogenic stimulation. The data show that an exposure to MF may influence the activity of lymphocytes in their response to mitogenic stimuli.
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Affiliation(s)
- Adam Roman
- Laboratory of Intracellular Signalling, Department of Biochemistry, Institute of Pharmacology, Polish Academy of Sciences, 31-343 Kraków, Poland.
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Nie K, Henderson A. MAP kinase activation in cells exposed to a 60 Hz electromagnetic field. J Cell Biochem 2004; 90:1197-206. [PMID: 14635193 DOI: 10.1002/jcb.10704] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
This research provides evidence that mitogen-activated protein kinase or extracellular signal-regulated kinase (MAPK/ERK) is activated in HL-60 human leukemia cells, MCF-7 human breast cancer cells, and rat fibroblast 3Y1 cells exposed to a 60 Hertz (Hz), 1 Gauss (G) electromagnetic field (EMF). The effects of EMF exposure were compared to those observed using 12-O-tetradecanoylphorbal-13-acetate (TPA) treatment. The level of MAPK activation in cells exposed to EMF was approximately equivalent to that in cells treated with 0.1-0.5 ng/ml of TPA. A role for protein kinase C (PKC) in the process leading to MAPK activation in EMF exposed cells is also suggested by the results. MAPK activation is negated by an inhibitor to PKCalpha, but not PKCdelta inhibitors, in cells subjected to EMF exposure or TPA treatment. Thus, similarities between the effects of EMF exposure and TPA treatment are supported by this investigation. This provides a possible method for revealing other participants in EMF-cell interaction, since the TPA induction pathway is well documented.
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Affiliation(s)
- K Nie
- Department of Biological Sciences and the Center for Gene Structure and Function, Hunter College of the City University of New York, Graduate Center of the City University of New York, New York, New York 10021, USA
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Simkó M, Mattsson MO. Extremely low frequency electromagnetic fields as effectors of cellular responses in vitro: Possible immune cell activation. J Cell Biochem 2004; 93:83-92. [PMID: 15352165 DOI: 10.1002/jcb.20198] [Citation(s) in RCA: 155] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
There is presently an intense discussion if electromagnetic field (EMF) exposure has consequences for human health. This include exposure to structures and appliances that emit in the extremely low frequency (ELF) range of the electromagnetic spectrum, as well as emission coming from communication devices using the radiofrequency part of the spectrum. Biological effects of such exposures have been noted frequently, although the implication for specific health effects is not that clear. The basic interaction mechanism(s) between such fields and living matter is unknown. Numerous hypotheses have been suggested, although none is convincingly supported by experimental data. Various cellular components, processes, and systems can be affected by EMF exposure. Since it is unlikely that EMF can induce DNA damage directly, most studies have examined EMF effects on the cell membrane level, general and specific gene expression, and signal transduction pathways. In addition, a large number of studies have been performed regarding cell proliferation, cell cycle regulation, cell differentiation, metabolism, and various physiological characteristics of cells. Although 50/60 Hz EMF do not directly lead to genotoxic effects, it is possible that certain cellular processes altered by exposure to EMF indirectly affect the structure of DNA causing strand breaks and other chromosomal aberrations. The aim of this article is to present a hypothesis of a possible initial cellular event affected by exposure to ELF EMF, an event which is compatible with the multitude of effects observed after exposure. Based on an extensive literature review, we suggest that ELF EMF exposure is able to perform such activation by means of increasing levels of free radicals. Such a general activation is compatible with the diverse nature of observed effects. Free radicals are intermediates in natural processes like mitochondrial metabolism and are also a key feature of phagocytosis. Free radical release is inducible by ionizing radiation or phorbol ester treatment, both leading to genomic instability. EMF might be a stimulus to induce an "activated state" of the cell such as phagocytosis, which then enhances the release of free radicals, in turn leading to genotoxic events. We envisage that EMF exposure can cause both acute and chronic effects that are mediated by increased free radical levels: (1) Direct activation of, for example macrophages (or other cells) by short-term exposure to EMF leads to phagocytosis (or other cell specific responses) and consequently, free radical production. This pathway may be utilized to positively influence certain aspects of the immune response, and could be useful for specific therapeutic applications. (2) EMF-induced macrophage (cell) activation includes direct stimulation of free radical production. (3) An increase in the lifetime of free radicals by EMF leads to persistently elevated free radical concentrations. In general, reactions in which radicals are involved become more frequent, increasing the possibility of DNA damage. (4) Long-term EMF exposure leads to a chronically increased level of free radicals, subsequently causing an inhibition of the effects of the pineal gland hormone melatonin. Taken together, these EMF induced reactions could lead to a higher incidence of DNA damage and therefore, to an increased risk of tumour development. While the effects on melatonin and the extension of the lifetime of radicals can explain the link between EMF exposure and the incidence of for example leukaemia, the two additional mechanisms described here specifically for mouse macrophages, can explain the possible correlation between immune cell system stimulation and EMF exposure.
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Affiliation(s)
- Myrtill Simkó
- Division of Environmental Physiology, Institute of Cell Biology and Biosystems Technology, University of Rostock, Albert-Einstein-Strasse 3, D-18059 Rostock, Germany.
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Oda T, Koike T. Magnetic field exposure saves rat cerebellar granule neurons from apoptosis in vitro. Neurosci Lett 2004; 365:83-6. [PMID: 15245783 DOI: 10.1016/j.neulet.2004.04.068] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2004] [Revised: 04/15/2004] [Accepted: 04/15/2004] [Indexed: 11/15/2022]
Abstract
Accumulating evidence demonstrates that extremely low frequency magnetic fields (ELF-MFs) are capable of modifying neuronal function. Here we examine the effect of ELF-MF exposure on neuronal apoptosis. For this purpose cerebellar granule neurons (CGNs) from postnatal rats were employed, which are known to undergo apoptosis under normal condition (5.4 mM K+) in vitro. Exposure to a rotating (50 Hz) ELF-MF for 5 days saved immature CGNs from apoptosis and promoted survival at the flux density of 300 mT, whereas virtually no neuronal survival was observed without exposure (sham). The survival-promoting effect of ELF-MFs occurred in a manner that depended on the size of culture flasks, suggesting that induced current plays a role in this phenomenon. A maximal survival-promoting effect was comparable to that of membrane depolarization (25 mM K+) and greater than that of brain-derived neurotrophic factor (BDNF). These results imply that ELF-MFs may serve as a potential tool for manipulating neuronal death and/or survival.
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Affiliation(s)
- Tsuyoshi Oda
- Abiko Research Laboratory, Bio-Science Department, Central Research Institute of Electric Power Industry, Chiba 270-1194, Japan
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Pasquini R, Villarini M, Scassellati Sforzolini G, Fatigoni C, Moretti M. Micronucleus induction in cells co-exposed in vitro to 50 Hz magnetic field and benzene, 1,4-benzenediol (hydroquinone) or 1,2,4-benzenetriol☆. Toxicol In Vitro 2003; 17:581-6. [PMID: 14599448 DOI: 10.1016/s0887-2333(03)00137-1] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The generation, transmission (e.g. power lines, transformers, service wires, and electrical panels), and use (e.g. home appliances, such as electric blankets, shavers, and televisions) of electrical energy is associated with the production of weak electric and magnetic fields (EMF) which oscillate 50 (Europe) or 60 (USA) times per second (power-line frequency), falling in the extremely-low frequency (ELF) region of the electromagnetic spectrum. Epidemiological reports suggest a possible association between exposure to ELF-EMF and an increased risk of cancer (e.g. childhood acute leukaemia). Benzene is an established human leukomogen. This xenobiotic, which is unlikely to be the ultimate carcinogen, is metabolized in the liver to its primary metabolite phenol, which is hydroxylated to hydroquinone (1,4-benzenediol) and 1,2,4-benzenetriol. In this in vitro approach, to test the genotoxic and / or co-genotoxic potency of ELF-EMF, the cytokinesis block micronucleus (MN) method with Jurkat cells has been used. A 50 Hz magnetic field (MF) of 5 mT field strength was applied for different length of time (from 1 to 24 h), either alone or with benzene, 1,4-benzenediol, or 1,2,4-benzenetriol. Our preliminary results show that, after 24 h exposure, the frequency of micronucleated cells in MF-exposed cultures is 1.9 fold higher than in sham-exposed (control) cultures. Benzene exposure does not show any cytogenetic activity, whereas 1,4-benzenediol or 1,2,4-benzenetriol alone significantly affect the number of MN in Jurkat cells, as compared to untreated cultures. Moreover, co-exposure to ELF-MF does not seem to affect the frequency of micronuclei induced by benzene, 1,4-benzenediol, or 1,2,4-benzenetriol.
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Affiliation(s)
- R Pasquini
- Department of Hygiene and Public Health, University of Perugia, Via del Giochetto, I-06126 Perugia, Italy
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Zeng QL, Chiang H, Hu GL, Mao GG, Fu YT, Lu DQ. ELF magnetic fields induce internalization of gap junction protein connexin 43 in Chinese hamster lung cells. Bioelectromagnetics 2003; 24:134-8. [PMID: 12524680 DOI: 10.1002/bem.10070] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
We have previously demonstrated that exposure of Chinese hamster lung (CHL) cells to 50 Hz magnetic fields (MFs) and/or 12-O-tetradecanoylphorbol-3-acetate (TPA)-inhibited gap junctional intercellular communication (GJIC). To explore and compare the mechanisms of GJIC inhibition induced by extremely low frequency (ELF) MF and TPA, the number and localization of connexin 43 (C x 43) were studied. The localization of C x 43 was determined with indirect immunofluorescence histochemical analysis and detected by confocal microscopy after exposing CHL cells to 50 Hz sinusoidal magnetic field at 0.8 mT for 24 h without or with TPA (5 ng/ml) for the last 1 h. The C x 43 levels in nuclei and in cytoplasm were examined by Western blotting analysis. The results showed that the cells exposed to MF and/or TPA displayed individual plaques at regions of intercellular contact, which were fewer than the normal cells in number, while the number of C x 43 in cytoplasm increased and congregated near the nuclei. Western blot analysis further demonstrated the quantity of changes in location of Cx43. These results suggest that reduction of C x 43 at regions of intercellular contact may be one of the mechanisms of GJIC inhibition induced by ELF MF.
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Affiliation(s)
- Q L Zeng
- Bioelectromagnetics Laboratory, Zhejiang University School of Medicine, Hangzhou, China.
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Zhou J, Yao G, Zhang J, Chang Z. CREB DNA binding activation by a 50-Hz magnetic field in HL60 cells is dependent on extra- and intracellular Ca(2+) but not PKA, PKC, ERK, or p38 MAPK. Biochem Biophys Res Commun 2002; 296:1013-8. [PMID: 12200150 DOI: 10.1016/s0006-291x(02)02022-3] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
To investigate the possible mechanism of gene transcription changes induced by magnetic field (MF), we examined the DNA binding behavior of the transcription factor cyclic-AMP responsive element binding protein (CREB) in HL60 cells after exposure to a 0.1mT 50-Hz extremely low frequency (ELF) sinusoidal MF by a gel shift assay. Magnetic field induced a time-dependent activation of CREB binding. The complex formation increased shortly after MF exposure for 10min, reaching a peak level after 1h, and then recovered to basal level at 4h after exposure. A novel MF-induced ATF2/ATF2 homodimer formation was observed after MF exposure for 30min, 1, and 2h. Furthermore, We found that the MF-induced increase of CREB DNA binding in HL60 cells was dependent on both extracellular and intracellular Ca(2+) but not PKA, PKC, ERK, or p38 MAPK by using various pathway inhibitors. These data indicate that MF exposure activates CREB DNA binding through calcium-related signal transduction pathways under our experimental conditions.
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Affiliation(s)
- Jiliang Zhou
- Laboratory of Molecular and Cell Biology, Institute of Biochemistry and Cell Biology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai 200031, People's Republic of China
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Yoshizawa H, Tsuchiya T, Mizoe H, Ozeki H, Kanao S, Yomori H, Sakane C, Hasebe S, Motomura T, Yamakawa T, Mizuno F, Hirose H, Otaka Y. No effect of extremely low-frequency magnetic field observed on cell growth or initial response of cell proliferation in human cancer cell lines. Bioelectromagnetics 2002; 23:355-68. [PMID: 12111756 DOI: 10.1002/bem.10006] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
An effect on the tumor promotion process, as represented by accelerated cell growth, has been indicated as one example of areas that demonstrate the possibility of biological effects of extremely-low frequency magnetic fields. We, therefore, exposed the five cell lines (HL-60, K-562, MCF-7, A-375, and H4) derived from human tumors to a magnetic field for 3 days to investigate the effects on cell growth. Prior to exposure or sham exposure, the cells were precultured for 2 days in low serum conditions. The number of growing cells was counted in a blind manner. To investigate the effect on the initial response of cell proliferation, two cell lines were synchronized in G1 phase by serum starvation and then exposed to a magnetic field for 18 h (H4 cells) or 24 h (MCF-7 cells), both with and without serum stimulation. The rate of DNA synthesis, taken as a measure of the cell proliferation, was determined by following the incorporation of [(3)H]-thymidine into the DNA. Three different magnetic field polarizations at both 50 and 60 Hz were used: linearly polarized (vertical); circularly polarized; and an elliptically polarized field. Magnetic field flux densities were set at 500, 100, 20 and 2 microT (rms) for the vertical field and at 500 microT (rms) for the rotating fields. No effect of magnetic field exposure was observed on either cell growth or the initial response of cell proliferation.
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Affiliation(s)
- Hiroaki Yoshizawa
- Power Engineering R & D Center, Tokyo Electric Power Co., Inc., Yokohama, Japan
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Richard D, Lange S, Viergutz T, Kriehuber R, Weiss DG, Myrtill S. Influence of 50 Hz electromagnetic fields in combination with a tumour promoting phorbol ester on protein kinase C and cell cycle in human cells. Mol Cell Biochem 2002; 232:133-41. [PMID: 12030371 DOI: 10.1023/a:1014802005672] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
It still is an unsolved issue whether exposure to power-line frequency electromagnetic fields (EMF) may promote carcinogenesis and if so whether it does so by influencing the proliferation, the survival, and the differentiation of cells. Since the family of protein kinases C (PKC) takes part in these processes by interacting with signal transduction pathways at several levels including the activation of transcription factors, we evaluated in the present study the effects of exposure of human amniotic fluid cells (AFC) to 50 Hz, 1 mT electromagnetic fields (EMF) alone and in combination with the tumour promoting phorbol ester 12-O-tetradecanoylphorbol 13-acetate (TPA) on the subcellular localization of PKC protein, on PKC enzyme activity, and on the cell cycle distribution. Quantitative analyses of the PKC expression pattern demonstrated the translocation of PKC from the cytosolic to the membrane fraction after exposure to 10, 50, 100 nM, and 1 microM TPA. EMF exposure alone showed no effect on PKC translocation. Co-exposure to 10, 50, and 100 nM TPA and I mT EMF revealed a significant additive effect (25 +/- 50, 66 +/- 29, 22 +/- 50%, respectively) with the most prominent increase at the concentration of 50 nM TPA. At the highest concentration of TPA used (1 microM) no additive effect of EMF could be observed. Data on enzymatic activity indicate that EMF modulate the PKC activity, showing a significant increase of 10 +/- 16% in total PKC activity after co-exposure to 50 nM TPA and 1 mT EMF when compared to 50 nM TPA alone. Flow cytometric analyses showed a transient cell cycle arrest in G0/G1-phase followed by a delayed transit through S-phase in response to TPA, which was, however, not enhanced by co-exposure with EMF. We conclude that in AFC cells TPA at lower concentrations (< or = 100 nM) induces a less than maximum effect on the PKC pathway, which can be enhanced by the applied EMF.
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Affiliation(s)
- Doreen Richard
- University of Rostock, Institute of Cell Biology and Biosystems Technology, Division of Environmental Physiology, Germany
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Robison JG, Pendleton AR, Monson KO, Murray BK, O'Neill KL. Decreased DNA repair rates and protection from heat induced apoptosis mediated by electromagnetic field exposure. Bioelectromagnetics 2002; 23:106-12. [PMID: 11835257 DOI: 10.1002/bem.103] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
In this study, we demonstrate that electromagnetic field (EMF) exposure results in protection from heat induced apoptosis in human cancer cell lines in a time dependent manner. Apoptosis protection was determined by growing HL-60, HL-60R, and Raji cell lines in a 0.15 mT 60 Hz sinusoidal EMF for time periods between 4 and 24 h. After induction of apoptosis, cells were analyzed by the neutral comet assay to determine the percentage of apoptotic cells. To discover the duration of this protection, cells were grown in the EMF for 24 h and then removed for 24 to 48 h before heat shock and neutral comet assays were performed. Our results demonstrate that EMF exposure offers significant protection from apoptosis (P<.0001 for HL-60 and HL-60R, P<.005 for Raji) after 12 h of exposure and that protection can last up to 48 h after removal from the EMF. In this study we further demonstrate the effect of the EMF on DNA repair rates. DNA repair data were gathered by exposing the same cell lines to the EMF for 24 h before damaging the exposed cells and non-exposed cells with H2O2. Cells were allowed to repair for time periods between 0 and 15 min before analysis using the alkaline comet assay. Results showed that EMF exposure significantly decreased DNA repair rates in HL-60 and HL-60R cell lines (P<.001 and P<.01 respectively), but not in the Raji cell line. Importantly, our apoptosis results show that a minimal time exposure to an EMF is needed before observed effects. This may explain previous studies showing no change in apoptosis susceptibility and repair rates when treatments and EMF exposure were administered concurrently. More research is necessary, however, before data from this in vitro study can be applied to in vivo systems.
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Affiliation(s)
- Jacob G Robison
- Department of Microbiology, Brigham Young University, Provo, Utah 84602, USA
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Laitl-Kobierska A, Cieślar G, Sieroń A, Grzybek H. Influence of alternating extremely low frequency ELF magnetic field on structure and function of pancreas in rats. Bioelectromagnetics 2002; 23:49-58. [PMID: 11793405 DOI: 10.1002/bem.97] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
The aim of this study was to estimate the influence on ultrastructure and function of endocrine and excretoric part of pancreas in rats of extremely low frequency alternating magnetic fields with parameters used in therapy in humans. The animals from the two experimental groups were exposed to a rectangular magnetic field waveform at a frequency of 10 Hz and induction of 1.8-3.8 mT--(group P) or a sinusoidal magnetic field at a frequency of 40 Hz and induction of 1.3-2.7 mT--(group S), respectively. The control rats were subjected to sham exposure. The cycle of 1, 3, 6, 9, and 14 daily exposure sessions lasting 30 min was made in all groups. Some of rats after finishing the cycle of 14 exposures were left in the same conditions except for the magnetic field for 3 or 10 days. In both groups of rats exposed to magnetic field, a distinct tendency to decrease glucose concentration, compared to control group, was observed during the exposure cycle. Serum glucose became normal after the end of exposure sessions. The concentrations of insulin in both groups of rats exposed to magnetic field were significantly higher, compared to the controls, during the exposure cycle. After the end of exposure cycle the concentration of insulin in group S became normal. In contrast, in group P the concentration of insulin decreased significantly on the last day of exposure, with a subsequent increase in the following days. The activity of alpha-amylase and lipase in the serum of experimental and control rats was not affected. In both groups of exposed rats, reversible changes of ultrastructure of the pancreatic islets, including expansion of the Golgi apparatus, extension of rough endoplasmatic reticulum, mitochondrial swelling, expansion of beta-granules and increase in number of empty vesicles in beta cells, occurred during the exposure. In acinar cells of exposed animals, a slight extension of rough endoplasmatic reticulum and mitochondrial swelling as transitory changes were observed. The structural and functional changes in pancreas are probably adaptative ones.
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Affiliation(s)
- Anna Laitl-Kobierska
- Chair and Clinic of Internal Diseases and Physical Medicine, Silesian Medical University, Bytom, Poland
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Hu GL, Chiang H, Zeng QL, Fu YD. ELF magnetic field inhibits gap junctional intercellular communication and induces hyperphosphorylation of connexin43 in NIH3T3 cells. Bioelectromagnetics 2001; 22:568-73. [PMID: 11748674 DOI: 10.1002/bem.85] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
The effects of extremely low frequency (ELF) magnetic field on gap junctional intercellular communication (GJIC), protein levels, and phosphorylation of connexin43 (Cx43) were studied in NIH3T3 cells. The suppression of GJIC by 24 h, 50 Hz, 0.8 mT ELF magnetic field, 2 h, 3 ng/ml 12-O-tetradecanoylphorbol-13-acetate (TPA), or ELF combined with TPA treatment was confirmed by the fluorescence recovery after photobleaching (FRAP) analysis with a confocal microscope. The results showed that ELF or TPA exposure induced 50-60% inhibition of GJIC (P < 0.01). ELF combined with TPA enhanced the inhibition of GJIC. Western blot analysis using Cx43 specific antibodies showed obviously decreasing non phosphorylated Cx43 (P(0)) induced by ELF and/or TPA exposure. On the other hand, cells treated with ELF and/or TPA displayed a hyperphosphorylated Cx43 band (P(3)). However, there was no obvious changes in the level of Cx43 protein. The results implied that the P(3) band appeared to result from phosphorylation of P(0). But it remains possible that upon the ELF exposure P(0) is converted to P(1), P(2) or both and that P(3) is formed from P(1) or P(2) resulting in the observed hyperphosphorylation pattern. From the present study, we conclude that ELF magnetic field inhibits GJIC and the main mechanism is the hyperphosphorylation of Cx43.
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Affiliation(s)
- G L Hu
- Microwave Laboratory, Zhejiang University School of Medicine, Hangzhou 310031, People's Republic of China.
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Simkó M, Droste S, Kriehuber R, Weiss DG. Stimulation of phagocytosis and free radical production in murine macrophages by 50 Hz electromagnetic fields. Eur J Cell Biol 2001; 80:562-6. [PMID: 11561907 DOI: 10.1078/0171-9335-00187] [Citation(s) in RCA: 70] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Effects of 50 Hz electromagnetic fields on phagocytosis and free radical production were examined in mouse bone marrow-derived macrophages. Macrophages were in vitro exposed to electromagnetic fields using different magnetic field densities (0.5-1.5 mT). Short-time exposure (45 min) to electromagnetic fields resulted in significantly increased phagocytic uptake (36.3% +/- 15.1%) as quantified by measuring the internalization rate of latex beads. Stimulation with 1 nM 12-0-tetradecanoylphorbol-13-acetate (TPA) showed the same increased phagocytic activity as 1 mT electromagnetic fields. However, co-exposure to electromagnetic fields and TPA showed no further increase of bead uptake, and therefore we concluded that because of the absence of additive effects, the electromagnetic fields-induced stimulation of mouse bone marrow-derived macrophages does not involve the protein kinase C signal transduction pathway. Furthermore, a significant increased superoxide production after exposure to electromagnetic fields was detected.
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Affiliation(s)
- M Simkó
- University of Rostock, Institute of Cell Biology and Biosystems Technology, Division of Environmental Physiology, Germany.
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Sun WJ, Yu YN, Chiang H, Fu YD, Lu DQ. EFFECTS OF 50 Hz MAGNETIC FIELD EXPOSURE ON PROTEIN TYROSINE PHOSPHORYLATION IN CULTURED CELLS. ACTA ACUST UNITED AC 2001. [DOI: 10.1081/jbc-100104144] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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Sonnier H, Marino AA. SENSORY TRANSDUCTION AS A PROPOSED MODEL FOR BIOLOGICAL DETECTION OF ELECTROMAGNETIC FIELDS. ACTA ACUST UNITED AC 2001. [DOI: 10.1081/jbc-100104140] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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Olsson G, Belyaev IY, Helleday T, Harms-Ringdahl M. ELF magnetic field affects proliferation of SPD8/V79 Chinese hamster cells but does not interact with intrachromosomal recombination. Mutat Res 2001; 493:55-66. [PMID: 11516715 DOI: 10.1016/s1383-5718(01)00158-9] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
Extremely low-frequency (ELF) magnetic fields have previously been shown to affect conformation of chromatin, cell proliferation, and calcium metabolism. Possible mutagenic and carcinogenic effects of ELF have also been discussed and tested. In this study, intrachromosomal recombination in the hprt gene after exposure to ELF magnetic field was investigated using the SPD8 recombination assay. SPD8 cells, derived from V79 Chinese hamster cells were exposed to ELF at a specific combination of static and ELF magnetic fields, that has been proven to have effects on chromatin conformation in several cell types. The genotoxic agent camptothecin (CPT) was used either as a positive control or simultaneously with ELF. We also analysed the effect of ELF and CPT on chromatin conformation with the anomalous viscosity time dependence (AVTD) technique, cell growth kinetics, and cell survival with clonogenic assay. DNA fragmentation was analysed by pulsed field gel electrophoresis (PFGE). ELF did not induce recombination alone, neither did ELF modify the recombinogenic effect of CPT. Although, there was no effect on cell survival in response to ELF exposure, inhibition of cell growth was observed. On the other hand, ELF exposure partly counteracted the growth inhibition seen with CPT. The data suggest that ELF exposure may stimulate or inhibit cell growth depending on the state of the cells. Although, ELF did not induce recombination, a weak but statistically significant DNA fragmentation comparable with CPT-induced fragmentation was observed with PFGE 48h after exposure to ELF.
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Affiliation(s)
- G Olsson
- Department of Genetic and Cellular Toxicology, Stockholm University, Svante Arrhenius väg 16-18, S-106 91 Stockholm, Sweden.
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47
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Winding P, Berchtold MW. The chicken B cell line DT40: a novel tool for gene disruption experiments. J Immunol Methods 2001; 249:1-16. [PMID: 11226459 DOI: 10.1016/s0022-1759(00)00333-1] [Citation(s) in RCA: 99] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
The use of the chicken DT40 B cell line is increasing in popularity due to the ease with which it can be manipulated genetically. It offers a targeted to random DNA integration ratio of more than 1:2, by far exceeding that of any mammalian cell line. The facility with which knockout cell lines can be generated, combined with a short generation time, makes the DT40 cell line attractive for phenotype analysis of single and multiple gene disruptions. Advantage has been taken of this to investigate such diverse fields as B cell antigen receptor (BCR) signaling, cell cycle regulation, gene conversion and apoptosis. In this review, we give a historical introduction and a practical guide to the use of the DT40 cell line, along with an overview of the main topics being researched using the DT40 cell line as a model system. These topics include B cell-specific subjects such as B cell signaling and Ig rearrangement, and subjects common to all cell types such as apoptosis, histones, mRNA modification, chromosomal maintenance and DNA repair. Attention is in each case brought to peculiarities of the DT40 cell line that are of relevance for the subject. Novel applications of the cell line, e.g., as a vector for gene targeting of human chromosomes, are also discussed in this review.
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Affiliation(s)
- P Winding
- Institute of Molecular Biology, Oster Farimagsgade 2A, DK-1353, K, Copenhagen, Denmark
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Gölfert F, Hofer A, Thümmler M, Bauer H, Funk RH. Extremely low frequency electromagnetic fields and heat shock can increase microvesicle motility in astrocytes. Bioelectromagnetics 2001; 22:71-8. [PMID: 11180251 DOI: 10.1002/1521-186x(200102)22:2<71::aid-bem1008>3.0.co;2-i] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
The effect of extremely low frequency electromagnetic fields (EMF) on microvesicles was examined in rat astrocytes by video-enhanced microscopy in combination with a perfusable cell chamber. The EMF effect was compared with the effect of heat shock (HS) and with a combination of them both. The velocity of microvesicles was measured using image processing software (NIH Scion image 1.61). After exposure of astrocytes to EMF (50 Hz, 100microT, 1 h), the velocity of microvesicles in astrocytes increased from 0.32 +/- 0.03 microm/s (n = 120, 95% CI) in the untreated control group to 0.41 +/- 0.03 microm/s (n = 175, 95% CI). Fifteen minutes after HS (45 degrees C, 10 min) the microvesicles showed a velocity of 0.56 +/- 0.03 microm/s (n = 125, 95% CI). Combination of HS and EMF led to an increase in velocity up to 0.54 +/- 0.03 microm/s (n = 110, 95% CI). No significant difference between HS and HS+EMF was found. Compared to the untreated control group, the increased microvesicle velocity of the exposed cells might be a stress response of the cell. It is possibly a sign of intensified intracellular traffic required to adjust the metabolic needs.
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Affiliation(s)
- F Gölfert
- Institut für Anatomie, Medizinische Fakultät, TU Dresden, Dresden, Germany
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49
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Lindström E, Still M, Mattsson MO, Mild KH, Luben RA. ELF magnetic fields initiate protein tyrosine phosphorylation of the T cell receptor complex. Bioelectrochemistry 2001; 53:73-8. [PMID: 11206927 DOI: 10.1016/s0302-4598(00)00125-2] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The human T cell line Jurkat registers a sinusoidal extremely low frequency (ELF), 0.10 mT magnetic fields (MFs) at the level of the plasma membrane. In this study, the protein tyrosine phosphorylation (PY) of two membrane-associated proteins in Jurkat cells were examined following a short-term MFs exposure, the zeta chains and the Src kinases p56lck. These proteins are interesting to study since the earliest biochemical event upon T cell receptor (TcR) activation is PY of the zeta chains. These signalling chains in the TcR complex was assessed using Western blotting and the activation of the p56lck kinase was analysed by in vitro kinase assay. The MFs exposure of Jurkat for 5 min activated p56lck and resulted in PY of zeta. These findings are in line with earlier reports on how MFs exposure affects signal transduction in Jurkat.
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Affiliation(s)
- E Lindström
- National Institute for Working Life, Umeå, Sweden.
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50
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Dibirdik I, Bofenkamp M, Skeben P, Uckun F. Stimulation of Bruton's tyrosine kinase (BTK) and inositol 1,4,5-trisphosphate production in leukemia and lymphoma cells exposed to low energy electromagnetic fields. Leuk Lymphoma 2000; 40:149-56. [PMID: 11426616 DOI: 10.3109/10428190009054892] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
We examined the effects of low energy electromagnetic field (EMF) exposure on the BTK kinase activity in B18-2 ([Btk-, rBTK(wt)] DT40) chicken lymphoma B cells and NALM-6 leukemic pre-B cells. Exposure of B 18-2 cells to EMF resulted in activation of BTK within 1 to 15 minutes in 8 of 8 independent experiments with stimulation indexes ranging from 1.2 to 13.3. While in some experiments the BTK stimulation was transient, in others the BTK activity continued to be significantly elevated for up to 4 hours. Similarly, exposure of NALM-6 cells to EMF resulted in activation of BTK within 30 minutes in 7 of 7 experiments with stimulation indexes ranging from 1.2 to 7.4. Stimulation of BTK activity in EMF exposed cells was associated with enhanced phosphoinositide turnover and increased inositol-1,4,5-trisphosphate (IP3) production in 7 of 13 experiments with DT40 cells and 7 of 13 experiments with NALM-6 cells. The likelihood and magnitude of an IP3 response after EMF exposure were similar to those after BCR ligation on DT40 cells and CD19 ligation on NALM-6 cells. These results confirm and extend our previous studies regarding EMF-induced biochemical signaling events in B-lineage lymphoid cells.
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MESH Headings
- Agammaglobulinaemia Tyrosine Kinase
- Animals
- Chickens
- Electromagnetic Fields
- Enzyme Activation/drug effects
- Enzyme Activation/radiation effects
- Humans
- Inositol 1,4,5-Trisphosphate/metabolism
- Inositol 1,4,5-Trisphosphate/radiation effects
- Isoenzymes/metabolism
- Isoenzymes/radiation effects
- Kinetics
- Leukemia, B-Cell/enzymology
- Leukemia, B-Cell/metabolism
- Leukemia, B-Cell/pathology
- Lymphoma, B-Cell/enzymology
- Lymphoma, B-Cell/metabolism
- Lymphoma, B-Cell/pathology
- Phospholipase C gamma
- Protein-Tyrosine Kinases/metabolism
- Protein-Tyrosine Kinases/radiation effects
- Tumor Cells, Cultured/radiation effects
- Type C Phospholipases/metabolism
- Type C Phospholipases/radiation effects
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Affiliation(s)
- I Dibirdik
- Department of Biochemistry, Parker Hughes Institute, Roseville, Minnesota 55113, USA.
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