Tang R, Xu Y, Ma F, Ren J, Shen S, Du Y, Hou Y, Wang T · 2016
Researchers studied the effect of extremely low frequency magnetic fields (ELF-MFs) on a lung metastatic melanoma mouse model and on the differentiation of regulatory T cells (Treg cells). Tumor-bearing mice were exposed to ELF-MFs at 0.4 T and 7.5 Hz for 2 hours per day for 27 days. Metastatic tumor burden in the lung was significantly decreased after ELF-MF treatment, and expressions of MMP2, MMP9, and Foxp3 in lung nodules significantly decreased in the ELF-MF group. In cell experiments, ELF-MF treatment reduced the Treg cell differentiation rate from 32.0% to 22.1%, increased reactive oxygen species (ROS), and inhibited p-AKT in T cells.
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.
Luo X et al. · 2016
Researchers tested whether lotus seedpod procyanidins (LSPCs) could protect mice against oxidative stress caused by extremely low-frequency electromagnetic field (ELF-EMF) exposure. Mice were exposed to ELF-EMF at 8 mT, 4 hours per day for 28 consecutive days, and blood and cerebral cortex were analyzed for antioxidant indices. LSPCs treatment augmented SOD, CAT, GSH-Px, GR and GST activity and significantly lowered MDA levels.
Kesari KK, Juutilainen J, Luukkonen J, Naarala J. · 2016
Hu Y et al. · 2016
Gok DK et al. · 2016
Researchers divided Wistar albino female rats into four groups: a control group, a prenatal-exposure group, a postnatal-exposure group, and a combined prenatal-plus-postnatal-exposure group. Pregnant rats in the prenatal and combined groups were exposed to a 50 Hz electric field at 12 kV/m for 1 hour per day during pregnancy, while postnatal animals were exposed for 68 days after birth. The latencies of visual evoked potential components were significantly prolonged in all exposed groups compared with controls. Retina TBARS levels, a marker of lipid peroxidation, were significantly elevated in all experimental groups compared with controls.
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.
Ansari AM et al. · 2016
Researchers exposed male adult NMRI mice to an extremely low frequency magnetic field at 0.5 mT and 50 Hz, either as a single 2-hour session or for 2 hours a day over 2 weeks. Depressive-like behavior was measured using the Forced Swimming Test, which records immobility time. Long-term exposure significantly reduced immobility time, while short-term exposure did not alter it.
Akpınar D et al. · 2016
Researchers exposed rats to an electric field at 12 kV/m for 1 hour per day, dividing them into control, prenatal, postnatal, and prenatal-plus-postnatal groups. The mismatch negativity amplitude was decreased in all exposed groups compared with the control group. Levels of 4-HNE, a marker of lipid peroxidation, were significantly increased in the postnatal group compared with the control group, while protein carbonyl levels were significantly decreased in the prenatal-plus-postnatal group compared with the control, prenatal, and postnatal groups.
Wang LF et al. · 2016
Researchers exposed Wistar rats to microwave radiation at 30 mW/cm2 for 5 minutes per day, 5 days per week, over a period of 2 months. Screening of the GRIN2B promoter region revealed a stable C-to-T variant at nucleotide position −217 that was not induced by microwave exposure. Following microwave exposure, NR2B protein expression decreased, while the Glu contents in the hippocampus and CSF increased, and memory impairment was observed in the TT genotype but not the CC and CT genotypes. In PC12 cells, the effects of the T allele were more pronounced than those of the C allele on transcription factor binding ability, transcriptional activity, NR2B mRNA, and protein expression.
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.
Nirwane A, Sridhar V, Majumdar A · 2016
Hidisoglu E et al. · 2016
Researchers exposed rats to 2100-MHz electromagnetic fields for 2 hours per day for either 1 or 10 weeks, then recorded visual evoked potentials and measured markers of oxidative stress in the brain. After 1 week of exposure, visual response latencies were shortened and several antioxidant markers were increased. After 1 or 10 weeks, the effects on visual response latencies differed: latencies were shortened in the 1-week group but prolonged in the 10-week group. The researchers concluded that the effects of EMF on visual evoked potentials depend on exposure duration.
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.
Deshmukh PS et al. · 2016
Researchers exposed male Fischer rats to microwave radiation for 90 days at 900, 1800, and 2450 MHz to investigate effects on cognitive function, heat shock protein 70 (HSP70) levels, and DNA damage in the brain. Cognitive function was tested using the elevated plus maze and Morris water maze, HSP70 levels were measured by ELISA, and DNA damage was assessed using alkaline comet assay. The results suggest that low-level microwave exposure at these frequencies may lead to hazardous effects on the brain.
(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.
Engels S, N-L Schneider, N Lefeldt, et al. · 2015
Yildirim et al. · 2015
Researchers aimed to assess the potential harmful effects of radiofrequency-electromagnetic radiation on sperm parameters. They collected semen samples and asked 1082 men to complete an anonymous questionnaire, excluding 51 with azoospermia. Increased internet usage was associated with decreased total motile sperm count and progressive motile sperm count. Wireless internet usage compared with wired connection was linked to lower progressive motile sperm count.
Unknown authors · 2015
Researchers exposed pregnant rats and their newborns to 2.45 GHz electromagnetic radiation for 1 h per day, 5 days a week, from pregnancy to 3 weeks of age. Lipid peroxidation increased in both brain and liver, while glutathione peroxidase activity and vitamins A, E, and β-carotene decreased in both organs. Glutathione and vitamin C concentrations fell in the brain but not in the liver, and the brain appeared more sensitive to oxidative injury than the liver.
