Ma Q et al. · 2016
Researchers studied the effects of extremely low-frequency electromagnetic fields (ELF-EMFs) on embryonic neural stem cells (eNSCs) in the laboratory. Cells were exposed to ELF-EMF at 50 Hz and 1 mT for 4 hours per day over 1, 2, and 3 days. ELF-EMF exposure increased the ratio of differentiated neurons and promoted neurite outgrowth without influencing astrocyte differentiation or cell apoptosis.
Falone S et al. · 2016
Researchers investigated whether hyperproliferation induced by a 50 Hz, 1 mT ELF magnetic field in SH-SY5Y human neuroblastoma cells is supported by improved defense against methylglyoxal and by rewiring of energy metabolism. The ELF magnetic field interfered with the biology of these malignant cells by further de-differentiating the cellular phenotype and increasing proliferative activity. The magnetic field also triggered cytoprotective mechanisms, including enhanced defense against methylglyoxal and more efficient management of metabolic energy, presumably to support rapid cell outgrowth.
Calabrò E. · 2016
Researchers exposed human SH-SY5Y neuronal-like cells to a 50 Hz magnetic field and examined protein changes using Fourier Transform Infrared Spectroscopy. After exposure, the vibration bands of the methylene group increased significantly, and a significant shift to low energies of the Amide I band was observed. An increase in the intensity of parallel and antiparallel β-sheet structures relative to the α-helix component was also observed after exposure. The authors interpreted these results as suggesting that both protein aggregation and increased hydrogen bonding occurred in the exposed neuronal-like cells.
Zhu W, Cui Y, Feng X, Li Y, Zhang W, Xu J, Wang H, Lv S. · 2016
Rats were treated with 2450 MHz microwave radiation at 50, 100, 150, or 200 mW/cm(2) for 6 min. Microwave treatment increased malondialdehyde content while decreasing antioxidative stress enzymes, activities of enzyme complexes I-IV, and ATP in myocardial tissues. Irradiated myocardial cells exhibited structural damage and underwent apoptosis. The researchers suggested that microwave irradiation could induce myocardial cell apoptosis by interfering with oxidative stress and cardiac energy metabolism.
Kerimoğlu G et al. · 2016
Male rats were divided into control, sham, and EMF-exposed groups, with the EMF group exposed to 900 MHz EMF for 1 hour per day between postnatal days 21 and 59. Biochemical analysis showed increased malondialdehyde and superoxide dismutase levels, and reduced glutathione and catalase levels in the EMF-exposed group compared to controls. The percentage of apoptotic myocardial cells in the EMF-exposed group was higher than in either the sham or control groups, and electron microscopy revealed altered Z band structure, decreased myofilaments, and pronounced vacuolization.
Yang LL et al. · 2016
Researchers investigated whether electromagnetic pulse (EMP) exposure could activate brain microglia via the p38 MAPK pathway in rats. The expression of OX-42, a marker of microglia activation, increased significantly at 1, 6 and 12 hours after EMP exposure, then recovered to sham group levels at 24 hours. Levels of NO, TNF-α and IL-10 also changed significantly in vivo and in vitro after EMP exposure. Results suggested that EMP exposure at 200 kV/m, 200 pulses could activate microglia in rat brain and affect its secretory function, with the p38 pathway involved.
Wu SX, Xu YQ, Di GQ, Jiang JH, Xin L, Wu TY · 2016
Researchers exposed male mice to environmental static electric fields for 35 days and measured antioxidant enzyme activity in liver homogenates. Superoxide dismutase activity increased significantly in both exposed groups on the 7th and 35th days, while glutathione S-transferase, glutathione peroxidase, and malonaldehyde showed only minimal changes. The researchers concluded that there was a weak relationship between exposure to environmental static electric fields and hepatic oxidative stress in living organisms.
Martínez MA, Úbeda A, Moreno J, Trillo MÁ · 2016
Researchers investigated how power frequency magnetic fields affect cell proliferation in NB69 cells and the role of p38 and JNK kinases and reactive oxygen species in that response. NB69 cultures were exposed to a 100 µT magnetic field, either intermittently for 24, 42 or 63 hours, or continuously for periods of 15 to 120 minutes, with or without p38 or JNK inhibitors and an antioxidant. Field exposure induced transient activation of p38, JNK, and ERK1/2, but only the p38 inhibitor blocked the proliferative effect. The antioxidant NAC blocked the field effects on cell proliferation and p38 activation, but not those on ERK1/2 activation.
Mahmoudinasab H, Sanie-Jahromi F, Saadat M · 2016
Researchers designed the study to evaluate the effect of EMFs on the mRNA levels of seven antioxidant genes in human MCF-7 cells. Three exposure patterns were tested at two field intensities, 0.25 mT and 0.50 mT, each with a total exposure time of 30 minutes. The MTT assay showed no cytotoxic effect on MCF-7 cells under any of the three exposure conditions at either field intensity. Under the 15-min-on/15-min-off pattern, the 0.50 mT intensity was associated with more up- or down-regulated genes than 0.25 mT, a statistically significant difference (P=0.041), while no such difference was found for the other two exposure patterns.
Kesari KK, Juutilainen J, Luukkonen J, Naarala J. · 2016
Hu Y et al. · 2016
Feng B, Ye C, Qiu L, Chen L, Fu Y, Sun W · 2016
Human amniotic FL cells were exposed to a 50-Hz magnetic field for different durations or intensities, then incubated with staurosporine for 4 hours. Magnetic field exposure alone had no significant effect on early apoptosis or cell viability. When cells were also treated with staurosporine, magnetic field exposure had a protective effect against early apoptosis, and this effect could be abolished by MPT inhibitors. The anti-apoptotic effect was completely eliminated when Akt was inhibited, suggesting that Akt activation was necessary for the effect.
Feng B, Dai A, Chen L, Qiu L, Fu Y, Sun W. · 2016
Researchers exposed human amniotic epithelial (FL) cells to a 50-Hz magnetic field to investigate the molecular mechanisms behind magnetic field-induced epidermal growth factor receptor clustering. Exposing FL cells to the magnetic field at intensities higher than 0.2 mT for 15 minutes enhanced total reactive oxygen species production. Blocking the NADPH oxidase enzyme with the inhibitor DPI suppressed magnetic field-induced cytoplasmic superoxide production and subsequent EGFR clustering, while mitochondrial superoxide production was not affected.
Feng B, Qiu L, Ye C, Chen L, Fu Y, Sun W. · 2016
Researchers exposed human amniotic epithelial cells to a 50-Hz magnetic field at 0.4 mT and examined mitochondrial permeability, mitochondrial membrane potential, and cytochrome c release. Exposure to the magnetic field at 0.4 mT for 60 min transiently induced mitochondrial permeability transition and Cyt-c release, although there was no significant effect on mitochondrial membrane potential. Cells exposed to the magnetic field showed increased intracellular reactive oxidative species levels and GSK-3β dephosphorylation, and the induced mitochondrial permeability transition was attenuated by a ROS scavenger or GSK-3β inhibitor.
Falone S et al. · 2016
Researchers exposed SK-N-BE(2) drug-resistant human neuroblastoma cells to a pulsed electromagnetic field and then challenged the cells with hydrogen peroxide to measure oxidative stress responses. The PEMF increased MnSOD-based antioxidant protection and reduced ROS production in response to a pro-oxidant challenge. The researchers suggested their work might lay foundation for the development of non-invasive PEMF-based approaches aimed at elevating endogenous antioxidant properties in cellular or tissue models.
Duong CN, Kim JY · 2016
Researchers studied whether EMF exposure could protect a human microglial cell line, HMO6, from cell death caused by oxygen-glucose deprivation (OGD), a model of ischemic injury. HMO6 cells were cultured for 4 hours under OGD with or without exposure to EMF at different combinations of frequencies and intensities, and cell survival, intracellular calcium, and ROS levels were measured. Among the combinations tested, 50 Hz/1 mT EMF was the most potent at reducing OGD-induced cell death and lowering intracellular calcium and ROS levels. A significant but less potent protective effect was also found at 10 Hz/1 mT, while no protective effect was found at other combinations.
Benassi B et al. · 2016
Researchers exposed SH-SY5Y cells to an extremely low frequency magnetic field set up to reproduce environmental prolonged exposure to ELF-MF (50 Hz, 1 mT) and then treated the cells with the pro-Parkinson's toxin MPP+. ELF-MF alone did not affect cell survival, shape, or morphology, but it did significantly impair redox homeostasis and thiol content, triggering an increase in protein carbonylation. When MPP+ was added to ELF-MF-exposed cells, toxicity was highly enhanced, with significant increases in ROS levels, oxidative damage, and caspase-dependent apoptosis. Pre-incubation with the thiol antioxidants N-acetyl-L-cysteine and GSH ethyl-ester significantly reduced oxidative damage and protected cells from death caused by the combined ELF-MF/MPP+ treatment.
Sırav B, Seyhan N · 2016
Researchers used young adult male and female Wistar albino rats to investigate whether pulse modulated 900 MHz and 1800 MHz radio-frequency radiation affects the permeability of the blood-brain barrier. Permeability was measured by quantifying Evans blue dye that passed into the brain after intravenous injection. In both male radio-frequency radiation exposed groups, blood-brain barrier permeability was found to be increased compared with controls, with 1800 MHz found more effective in males. For female rats, 900 MHz exposure was associated with increased permeability, but no statistical difference was found between the 1800 MHz exposed and control groups.
Erdem Koç G et al. · 2016
Researchers established seven groups of pregnant rats and exposed some to 900 MHz EMF for 60 minutes per day during the gestation period. After birth, male rat pups were selected and the total number of pyramidal neurons in the hippocampal region was counted using the optical fractionator technique. The total number of pyramidal cells in the EMF group was significantly lower than in the control, sham, EMF plus melatonin, and EMF plus omega-3 groups. No difference was observed between any groups in terms of rats' body or brain weights.
(E) Barthélémy A et al. · 2016
Researchers exposed male Sprague Dawley rats for 15 minutes at 0, 1.5, or 6 W/kg, or for 45 minutes at 6 W/kg, to radiofrequency electromagnetic fields. Memory, emotionality, and locomotion were tested using fear conditioning, the elevated plus maze, and the open field. Long-term memory was reduced and cytosolic GFAP was increased in the hippocampus and in the olfactory bulb at 6 W/kg. No MBP or Aβ1–40 expression modification was shown. The study suggests that RF EMF-induced astrogliosis had functional consequences on memory but did not demonstrate that it was secondary to neuronal damage.
Unknown authors · 2015
Researchers exposed HaCaT human keratinocytes to ELF-EMF at 50 Hz and 1 mT and monitored cell cycle, growth, and viability using FACS and BrdU assays. They also measured gene expression changes with microarray and qRT-PCR, and assessed mTOR, Akt, and MAPK protein levels by Western blot. Short ELF-EMF exposure modulated gene expression patterns involved in cell proliferation and the cell cycle, with mTOR activation identified as the main molecular target. The data showed increased PI3K/Akt pathway activity and ERK signaling activation. ELF-EMF selectively modulated multiple genes related to biological processes such as wound healing.
Unknown authors · 2015
Unknown authors · 2015
Researchers exposed two Gram-positive and two Gram-negative bacterial species to six magnetic field conditions in broth cultures. The conditions included three 'Thomas' pulsed frequency-modulated patterns, a strong-static 'puck' magnet upwards of 5000G, a pair of rotating magnets at ~30rpm, and a 'Resonator' dynamic field generator with average intensity of 250μT. Growth rate was measured by optical density at 600nm every hour. ELF-EMF conditions significantly affected growth rates while static magnetic field conditions were not statistically significant. The 'Resonator' dynamic magnetic field increased growth rates of Staphylococcus epidermidis, Staphylococcus aureus, and Escherichia coli, while slowing growth of Serratia marcescens.
Malkemper EP et al. · 2015
The researchers tested the wood mouse Apodemus sylvaticus for magnetoreception using a simple behavioural assay in which mice were allowed to build nests overnight in a visually symmetrical, circular arena. When plotted with respect to magnetic north, the nests were bimodally clustered in the northern and southern sectors, indicating the animals used magnetic cues. Wood mice exposed to a 0.9 to 5 MHz frequency sweep changed their preference from north-south to east-west. A constant frequency field tuned to the Larmor frequency (1.33 MHz) had no effect on mouse orientation. The study demonstrated magnetoreception in wood mice and provided first evidence for a radical-pair mechanism in a mammal.
Liu YX et al. · 2015
Researchers exposed human glioblastoma cell lines U251-MG and U87-MG to 1950-MHz TD-SCDMA fields at a maximum SAR of 5.0 W/kg for 12, 24, and 48 hours. They measured cell morphology, apoptosis, cell cycle, growth, gene and protein expression, tumor formation, and invasiveness. No significant differences in biological features or tumor formation ability were found between exposed and unexposed cells. Exposure did not act as a cytotoxic or tumor-promoting agent affecting proliferation or gene expression.
