PMID: 

Front Biosci. 2008 May 1 ;13:6106-25. Epub 2008 May 1. PMID: 18508647

Abstract Title: 

Effects of static magnetic fields in biology: role of free radicals.

Abstract: 

Biological systems can respond to a wide range of static magnetic fields (SMF). Some of these responses seem to be mediated partly through free radical reactions. For example, in magnetic sense and navigation using the geomagnetic field, one of the most promising mechanisms for explaining magnetic compass is"a radical pair mechanism". Biological free radicals are most commonly oxygen or nitrogen based with an unpaired electron, leading to the terms"reactive oxygen species (ROS)"or"reactive nitrogen species (RNS)". When applying SMF to medical treatment, coupling SMF exposure with possible chemotherapy of cancers is a novel fascinating area that SMF could enhance agent-induced ROS production against tumors. In addition, one of the potent mechanisms of SMF effects on hemodynamics and blood pressure has sometimes been linked to nitric oxide pathway. However, health and environmental concerns have been raised because the SMF effects on oxidative stress leading to genetic mutation and apoptosis/necrosis have been found. It seems to take place from free radical generation.

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PMID: 

Pathophysiology. 2000 Jul ;7(2):127-130. PMID: 10927192

Abstract Title: 

Pulsed magnetic fields enhance nitric oxide synthase activity in rat cerebellum.

Abstract: 

The effect of pulsed magnetic fields on nitric oxide synthase (NOS) activity in the rat brain was investigated. Sprague-Dawley rats (male, 200-250 g body weight) brain were dissected regionally, and the crude enzyme solutions were treated with pulsed DC, AC or static DC magnetic fields at 0 degrees C for 1 h. After exposure, NOS activity was measured as nitrite and nitrate levels generated from incubation with arginine, CaCl(2) and beta-nicotinamide adenine dinucleotide phosphate. Under these experimental conditions, neither AC nor static DC field treatment showed any significant change in NOS activity. A significant increase in NOS activity was observed in the cerebellum (111.2+/-2.0%, P

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PMID: 

Pathophysiology. 2000 Jul ;7(2):127-130. PMID: 10927192

Abstract Title: 

Pulsed magnetic fields enhance nitric oxide synthase activity in rat cerebellum.

Abstract: 

The effect of pulsed magnetic fields on nitric oxide synthase (NOS) activity in the rat brain was investigated. Sprague-Dawley rats (male, 200-250 g body weight) brain were dissected regionally, and the crude enzyme solutions were treated with pulsed DC, AC or static DC magnetic fields at 0 degrees C for 1 h. After exposure, NOS activity was measured as nitrite and nitrate levels generated from incubation with arginine, CaCl(2) and beta-nicotinamide adenine dinucleotide phosphate. Under these experimental conditions, neither AC nor static DC field treatment showed any significant change in NOS activity. A significant increase in NOS activity was observed in the cerebellum (111.2+/-2.0%, P

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PMID: 

Int J Radiat Biol. 2016 10 ;92(10):583-9. Epub 2016 Jul 19. PMID: 27430265

Abstract Title: 

Evaluation of cell viability, DNA single-strand breaks, and nitric oxide production in LPS-stimulated macrophage RAW264 exposed to a 50-Hz magnetic field.

Abstract: 

PURPOSE: Synergistic effects between cellular oxidative stress and magnetic fields may explain the adverse biological effects of 50/60 Hz magnetic fields. To determine whether this hypothesis holds in macrophage RAW264 cells, we measured DNA single-strand breaks (SSB), cell viability, and nitric oxide (NO) production in cells with or without exposure to 0.5-mT, 50-Hz magnetic fields for 24 h and with or without simultaneous stimulation via the bacterial endotoxin, lipopolysaccharide (LPS).MATERIALS AND METHODS: Macrophages stimulated with 10 ng/ml LPS for 1 h were exposed to or not exposed to a magnetic field and were then subjected to (1) the alkaline comet assay to measure SSBs, (2) trypan-blue exclusion assay for cell viability, and (3) measurements of NO for evaluation of oxidative stress.RESULTS: The 50-Hz magnetic field enhanced DNA SSB and decreased cell viability only in the LPS-stimulated macrophages in which NO production was greatly enhanced. The magnetic field alone did not alter NO production.CONCLUSION: Co-stimulation of the cell with LPS and a 50-Hz magnetic field promoted SSB and lowered cell viability, but these were not mediated by LPS-induced NO production.

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PMID: 

Biomed Res Int. 2017 ;2017:5675086. Epub 2017 Apr 12. PMID: 28497056

Abstract Title: 

Direction-Dependent Effects of Combined Static and ELF Magnetic Fields on Cell Proliferation and Superoxide Radical Production.

Abstract: 

Proliferation of human umbilical vein endothelial cells was stimulated by a nearly vertical 60 or 120 T static magnetic field (MF) in comparison to cells that were shielded against MFs. When the static field was combined with an extremely low frequency (ELF) MF (18 Hz, 30 T), proliferation was suppressed by a horizontal but not by a vertical ELF field. As these results suggested that the effects of an ELF MF depend on its direction in relation to the static MF, independent experiments were carried out to confirm such dependence using 50 Hz MFs and a different experimental model. Cytosolic superoxide level in rat glioma C6 cells exposed in the presence of a nearly vertical 33 T static MF was increased by a horizontal 50 Hz, 30 T MF, but not affected by a vertical 50 Hz MF. The results suggest that a weak ELF MF may interact with the static geomagnetic field in producing biological effects, but the effect depends on the relative directions of the static and ELF MFs.

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PMID: 

Free Radic Biol Med. 2010 Feb 15 ;48(4):579-89. Epub 2009 Dec 11. PMID: 20005945

Abstract Title: 

Modulation of redox status and calcium handling by extremely low frequency electromagnetic fields in C2C12 muscle cells: A real-time, single-cell approach.

Abstract: 

The biological effects of electric and magnetic fields, which are ubiquitous in modern society, remain poorly understood. Here, we applied a single-cell approach to study the effects of short-term exposure to extremely low frequency electromagnetic fields (ELF-EMFs) on muscle cell differentiation and function using C2C12 cells as an in vitro model of the skeletal muscle phenotype. Our focus was on markers of oxidative stress and calcium (Ca(2+)) handling, two interrelated cellular processes previously shown to be affected by such radiation in other cell models. Collectively, our data reveal that ELF-EMFs (1) induced reactive oxygen species production in myoblasts and myotubes with a concomitant decrease in mitochondrial membrane potential; (2) activated the cellular detoxification system, increasing catalase and glutathione peroxidase activities; and (3) altered intracellular Ca(2+)homeostasis, increasing the spontaneous activity of myotubes and enhancing cellular reactivity to a depolarizing agent (KCl) or an agonist (caffeine) of intracellular store Ca(2+)channels. In conclusion, our data support a possible link between exposure to ELF-EMFs and modification of the cellular redox state, which could, in turn, increase the level of intracellular Ca(2+)and thus modulate the metabolic activity of C2C12 cells.

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PMID: 

Cell Physiol Biochem. 2010 ;26(6):947-58. Epub 2011 Jan 4. PMID: 21220925

Abstract Title: 

Effects of acute and chronic low frequency electromagnetic field exposure on PC12 cells during neuronal differentiation.

Abstract: 

BACKGROUND/AIMS: The purpose of this study was to provide information about the in vitro neuritogenesis during cell exposure to extremely low frequency electromagnetic fields (ELF-EMFs) of different intensities and durations using pheochromocytoma-derived cell line (PC12 cells) as neuronal model.METHODS: Proliferative rates and neuritogenesis were tested by colorimetric assay and morphological analysis, respectively; reactive oxygen species (ROS) levels and intracellular Ca(2+) variations monitored using single cell videomicroscopy.RESULTS: The long-lasting ELF-EMF exposure (0.1-1.0 mT) did not appear to significantly affect the biological response (proliferation and neuritogenesis). However, during the acute ELF-EMF exposure (30 min), in undifferentiated PC12 cells, there were increased ROS levels and decreased catalase activity, that, conversely, resulted increased after chronic exposure (7 days) at 1.0 mT. Acute exposure (0.1-1.0 mT) affected the spontaneous intracellular Ca(2+) variations in undifferentiated cells, in which basal intracellular Ca(2+) resulted increased after chronic exposure. In addition acute exposure affected cell response to a depolarizing agent, while basal membrane potential was not changed.CONCLUSION: Even if further studies remain necessary to identify the ROS/intracellular Ca(2+)cross-talking pathway activated by ELF-EMF exposure, we support the hypothesis that ROS and Ca(2+) could be the cellular"primum movens"of the ELF-EMF induced effects on biological systems.

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PMID: 

Electromagn Biol Med. 2017 ;36(1):102-113. Epub 2016 Jul 11. PMID: 27399314

Abstract Title: 

Magnetic fields, radicals and cellular activity.

Abstract: 

Some effects of low-intensity magnetic fields on the concentration of radicals and their influence on cellular functions are reviewed. These fields have been implicated as a potential modulator of radical recombination rates. Experimental evidence has revealed a tight coupling between cellular function and radical pair chemistry from signaling pathways to damaging oxidative processes. The effects of externally applied magnetic fields on biological systems have been extensively studied, and the observed effects lack sufficient mechanistic understanding. Radical pair chemistry offers a reasonable explanation for some of the molecular effects of low-intensity magnetic fields, and changes in radical concentrations have been observed to modulate specific cellular functions. Applied external magnetic fields have been shown to induce observable cellular changes such as both inhibiting and accelerating cell growth. These and other mechanisms, such as cell membrane potential modulation, are of great interest in cancer research due to the variations between healthy and deleterious cells. Radical concentrations demonstrate similar variations and are indicative of a possible causal relationship. Radicals, therefore, present a possible mechanism for the modulation of cellular functions such as growth or regression by means of applied external magnetic fields.

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PMID: 

Plant Sci. 2018 Dec ;277:139-144. Epub 2018 Aug 10. PMID: 30466579

Abstract Title: 

On the mechanism of the cell cycle control of suspension-cultured tobacco cells after exposure to static magnetic field.

Abstract: 

One of the main sites of the magnetic fields influence on living cells is the cell cycle. The intensity of this influence however, varies depending on the cell type and the duration of the treatment. Suspension of cultured tobacco cells (Nicotiana tabacum cv. Barley 21) were synchronized via sucrose starvation at their stationary growth phase. The cells were then exposed to 0.2 m T SMF up to 24 h. The progression of different cell cycle phases was monitored through flow cytometry in a time course manner. Expression of cell cycle controlling genes and amounts of certain signaling molecules were measured as well. Exposure to SMF delayed G1.S transition which was accompanied by decrease of cyclin-dependent kinases A (CDK A) and D-type cyclin, but an increase in the adenylyl cyclase (AC), transcription factor E2F, retinoblastoma protein (Rbp), and CDK-inhibitor protein 21 (p21) transcript accumulation. Exposure to SMF also increased the contents of nitric oxide (NO), hydrogen peroxide (HO), and salicylic acid (SA), compared to the control group. The results suggest a signaling pathway triggered by SMF starting from accumulation of NO and HOfollowed by downstream events including the increase of cyclic nucleotides and subsequent decrease of both CDKA and CycD.

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PMID: 

Int J Radiat Biol. 2017 08 ;93(8):818-830. Epub 2017 May 25. PMID: 28452248

Abstract Title: 

Response of aquatic protists to electric field exposure.

Abstract: 

PURPOSE: To test the effects of short-term exposure of aquatic organisms to electric field (EF) with negligible magnetic component.MATERIALS AND METHODS: We built a plate capacitor that served as a source of EF of strengths that can be found in nature near transmission lines. We exposed two cultured protist species Euglena viridis and Paramecium caudatum to EFs for 24 hours and monitored their abundance, morphology, intracellular superoxide anion (by dihydroethidium [DHE]), hydrogen peroxide by (HDCF) and lipid peroxidation (MDA) contents, catalase (CAT) and superoxide dismutase (SOD) activity.RESULTS: We found that even short-term exposure to low strength EF causes changes in population abundance, morphology and oxidative stress response in both species. As the EF strength increased, abundance of both species decreased. However, at weaker EFs, fission rates were seemingly promoted. We noted a decrease in size in both organisms in directions perpendicular to their fission planes correlated with EF strength. DHE and HDCF fluorescence intensity and SOD activity were higher in organisms exposed to the stronger EFs.CONCLUSIONS: We suggest that the electric component of the field, rather than the magnetic, is the main cause of all the noted effects. As a result, aquatic organisms should be given greater importance in studies assessing the effects of EMFs in spite of the attenuating effects of water to EF strengths.

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