Unknown authors · 2017
Researchers exposed isolated Agrobacterium tumefaciens to square amplitude modulated waves at different extremely low frequencies to find a resonance frequency that inhibits growth. The carrier was a 10 MHz sine wave at ±10 Vpp modulated with ±2 Vpp depth at a constant field strength of 200 V/m and 28 °C. Exposure to 1.0 Hz QAMW for 90 minutes inhibited bacterial growth by 49.2%. Antibiotics became more effective against the bacteria after exposure. In tomato plants, crown gall symptoms were more aggressive with non-exposed bacteria than with exposed bacteria.
Samiee F, Samiee K. · 2017
Researchers examined how extremely low frequency electromagnetic field (ELF-EMF) exposure at 50 Hz affected brain tissue in Cyprinus carpio, a common carp species from the Caspian Sea. A total of 200 healthy fish were divided into a sham-exposed group and an experimental group exposed to five different magnetic field intensities (0.1, 1, 3, 5, and 7 mT) at two different exposure times (0.5 and 1 h). Exposure caused severe histopathological changes in the brain at field intensities of 3 mT or higher, leading to brain necrosis, with field intensity and duration of exposure identified as key parameters in causing lesions.
Unknown authors · 2017
The study examined how low-frequency magnetic fields affect morphine tolerance in rats. Rats received morphine 10 mg/kg daily for eight days and were exposed to magnetic fields at 50 Hz (1, 50, 100 µT) before, immediately, or 30 minutes after each injection, and also to 0.5, 6, 12, and 30 Hz at 100 µT before injection. Exposure to 50 Hz at 1 µT and 30 Hz at 100 µT immediately before injection, and 50 Hz at 100 µT after injection, prevented tolerance, whereas exposure to 50 Hz at 1, 50, and 100 µT 30 minutes after injection did not preserve analgesia.
Cichoń N et al. · 2017
Patients were divided into two groups, both undergoing the same 4-week rehabilitation program, with one group also receiving daily ELF-EMF exposure. The ELF-EMF group was exposed to a field of 40 Hz and 7 mT for 15 minutes per day. ELF-EMF significantly increased 3-nitrotyrosine and nitrate/nitrite levels, while NOS2 expression was insignificantly decreased in both groups. The researchers concluded that ELF-EMF therapy is capable of promoting recovery in poststroke patients.
Falone S et al. · 2017
Researchers investigated whether a 50 Hz, 1 mT ELF magnetic field promoted hyperproliferation and improved defence against reactive oxygen species in SH-SY5Y human neuroblastoma cells. The field activated antioxidant and detoxification pathways linked to more aggressive cell behavior, along with upregulation of major sirtuins and increased NRF2 signaling. Exposure to a 50 Hz magnetic field as low as 100 µT may still be able to alter cancer cell behavior and responses to clinically relevant drugs.
Giorgi G et al. · 2017
Researchers exposed human neural cells (BE(2)C) to an extremely low frequency pulsed magnetic field (50 Hz, 1 mT) for 24 and 48 hours, alone and combined with oxidative stress, to study DNA methylation changes. Exposure to the magnetic field alone or oxidative stress alone produced only weak changes in DNA methylation levels at different CpG sites. When the two exposures were combined, a significant decrease in DNA methylation levels was found at different CpG sites, and most of those changes were transient.
Naarala J et al. · 2017
Researchers studied how the direction of combined static and extremely low frequency (ELF) magnetic fields affected cell proliferation and superoxide radical production. Proliferation of human umbilical vein endothelial cells was stimulated by a nearly vertical 60 or 120 μT static magnetic field compared with cells that were shielded against magnetic fields. When the static field was combined with an extremely low frequency ELF field, proliferation was suppressed by a horizontal but not by a vertical ELF field.
Pooam M, Nakayama M, Nishigaki C, Miyata H · 2017
Researchers exposed RAW264 macrophage cells to a 50-Hz sinusoidal magnetic field at 0.1 mT or 0.5 mT and measured superoxide production, HSP70 expression, and mitochondrial membrane potential. The magnetic field enhanced production of superoxide and the expression of HSP70. The researchers suggested that the 50-Hz magnetic field diminished mitochondrial membrane potential, which led to increased superoxide production and HSP70 expression.
Solek P et al. · 2017
Researchers investigated the effects of pulsed and continuous electromagnetic fields on two mouse spermatogenic cell lines, GC-1 spg and GC-2 spd, in vitro. The researchers evaluated mitochondrial metabolism, morphology, proliferation rate, viability, cell cycle progression, oxidative stress balance, and regulatory proteins. The results strongly suggested that EMF induced oxidative and nitrosative stress-mediated DNA damage, resulting in p53/p21-dependent cell cycle arrest and apoptosis. The researchers concluded that electromagnetic field impairs male fertility by inducing p53/p21-mediated cell cycle arrest and apoptosis.
Zeng Y, Shen Y, Hong L, Chen Y, Shi X, Zeng Q, Yu P · 2017
Researchers evaluated the biological effects of different patterns of extremely low frequency magnetic field exposure on primary cultured hippocampal neurons, looking at viability, apoptosis, genomic instability, and oxidative stress. Repeated exposure to a 50-Hz 2-mT field for 8 hours per day decreased cell viability and increased the production of intracellular reactive oxygen species. The researchers noted that none of the repeated exposure patterns had significant effects on DNA damage, apoptosis, or autophagy, suggesting no severe biological consequences in the cultured neurons.
Cichoń N et al. · 2017
Researchers studied 48 stroke patients undergoing rehabilitation, with half receiving additional exposure to extremely low-frequency electromagnetic fields (40 Hz) for 15 minutes daily. The EMF-exposed group showed increased levels of nitric oxide compounds in their blood and demonstrated better functional and mental recovery compared to the control group. This suggests that specific EMF frequencies might help enhance brain healing after stroke.
Zeng Y, Shen Y , Hong L, Chen Y, Shi X, Zeng Q, Yu P. · 2017
Researchers exposed brain cells important for memory to power-line frequency magnetic fields for eight hours daily. The exposure reduced cell health and increased cellular damage from free radicals, suggesting household electrical fields may stress brain cells without causing severe damage.
Ehnert S et al. · 2017
The study investigated how ELF-PEMF exposure modulates human osteoblast function via reactive oxygen species. Single ELF-PEMF exposure induced ROS production in human osteoblasts without reducing intracellular glutathione. Repetitive exposure more than three times reduced ROS levels, suggesting changes in the antioxidative stress response. The researchers concluded that ELF-PEMF treatment favors differentiation of human osteoblasts by producing non-toxic ROS that induce antioxidative defense mechanisms.
Clarke D et al. · 2017
Researchers tested four different repetitive magnetic stimulation frequencies on primary neonatal astrocyte cultures and measured calcium responses. Only 1 Hz stimulation produced a statistically significant rise in intracellular calcium in both cytoplasmic and nuclear compartments. This calcium increase did not change astrocyte migration or proliferation in a scratch assay. However, 1 Hz stimulation reduced astrocyte hypertrophy 24 hours after scratch injury. The authors concluded that the results provide preliminary evidence that repetitive magnetic stimulation can influence astrocyte physiology.
Villarini M et al. · 2017
Researchers exposed SH-SY5Y5 and SK-N-BE-2 neuroblastoma cells to 50 Hz magnetic fields at 0.01, 0.1, or 1 mT, aluminum chloride at 4 or 40 µM, or both together for 1 hour continuously or 5 hours intermittently. They measured DNA damage with the comet assay, redox status via GSH/GSSG ratio, and Hsp70 expression by western blot and real-time RT-PCR. Neither the magnetic field nor aluminum alone caused DNA damage, altered the GSH/GSSG ratio, or changed Hsp70 levels, and combined exposure showed no synergistic toxic effect.
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.
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.
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.
Unknown authors · 2016
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.
Kesari KK, Juutilainen J, Luukkonen J, Naarala J. · 2016
Hu Y et al. · 2016
Researchers exposed genetically modified mice with Alzheimer's disease to extremely low frequency magnetic fields (50Hz, 500μT) for three months daily. The magnetic field exposure improved cognitive function, reduced brain cell death, and decreased tau protein abnormalities that are hallmarks of Alzheimer's disease. This suggests that controlled magnetic field exposure might have therapeutic potential for neurodegenerative conditions.
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.
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.
Salunke BP, Umathe SN, Chavan JG. · 2016
Researchers exposed mice to 50 Hz magnetic fields (the same frequency as power lines) for up to 120 days and found it caused significant anxiety-like behavior. The study identified that these fields disrupt brain chemistry by affecting NMDA receptors and increasing glutamate levels in key brain regions. This suggests that long-term exposure to power-frequency magnetic fields can alter brain function and behavior.
