Reba Goodman et al. · 2009
Researchers used regenerating planaria Dugesia dorotocethala as a model to determine whether an intermittent modulated extremely low frequency electromagnetic field produces elevated levels of hsp70 and stimulates intracellular pathways known to be involved in injury and repair. Individual head and tail portions from the same worm were exposed to a 60 Hertz 80 milliGauss ELF-EMF for 1 h twice daily for 15 days post-transection. ELF-EMF exposure caused a significant increase in regeneration for both heads and tails, and exposed tails developed eyes at day seven post-transection, while sham control tails showed the first appearance of eyes 48 h later. Exposed animals also showed an elevation in hsp70 protein, an activation of an ERK cascade, and an increase in SRF-SRE binding.
George I et al. · 2008
Researchers exposed Sprague-Dawley rats to a 60 Hz, 8 µT electromagnetic field for 30 minutes before inducing ischemia-reperfusion (I-R) injury to the heart. Significant upregulation of the HSP70 gene and increased hsp70 levels were measured in response to EMF pre-exposures. Systolic contractile function showed significant recovery after 30 minutes of reperfusion in EMF-exposed animals, and diastolic function was markedly improved as well.
Di Carlo A, White N, Guo F, Garrett P, Litovitz T. · 2002
Chick embryos were exposed to ELF-EMFs at 8 microT continuously for 4 days, or to ELF or RF EMFs repeated daily for 4 days in sessions of 20, 30, or 60 minutes once or twice daily. Several exposure protocols produced statistically significant decreases in protection against hypoxic stress, including continuous ELF and 30 or 60 minute ELF twice daily, or 30 or 60 minute once daily RF. Following 4 days of ELF-EMF exposure, HSP70 levels declined by 27% compared to controls.
Sokolovic D et al. · 2008
Researchers exposed Wistar rats to microwave radiation from a mobile test phone for 20, 40, and 60 days to evaluate oxidative stress in brain tissue and whether melatonin could reduce it. Exposure led to a significant increase in malondialdehyde and carbonyl group concentrations in brain tissue, along with decreased catalase activity and increased xanthine oxidase activity. Melatonin treatment significantly prevented the rise in MDA content and xanthine oxidase activity after 40 days of exposure, but was unable to prevent the decrease in catalase activity or the increase in carbonyl group content.
Sharifian A, Gharavi M, Pasalar P, Aminian O · 2009
Researchers measured antioxidant markers in 46 spot welders occupationally exposed to extremely low frequency magnetic fields and compared results with a non-exposed control group. In the red blood cells of exposed workers, SOD activity decreased by 22% and GPX activity decreased by 12.3%, both statistically significant. Total serum antioxidant status showed no significant difference between the two groups. The researchers concluded that ELF-MF could influence red blood cell antioxidant activity and might act as an oxidative stressor.
Laszlo AM et al. · 2018
Researchers exposed turkeys to extremely low frequency electromagnetic fields (50 Hz; 10 μT) for 3 weeks and then observed the birds for a 5-week regeneration period without exposure. Norepinephrine-activated β-adrenoceptor function decreased in the treated birds in a time-dependent manner, while toxicological parameters in the serum showed no differences compared to normal ranges. The decreased β-adrenoceptor function was compensated by the homeostatic complex during the 5-wk regeneration period.
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.
Kesari KK, Juutilainen J, Luukkonen J, Naarala J. · 2016
Poniedzialek B et al. · 2013
Researchers investigated the effect of low frequency electromagnetic field on reactive oxygen species production in human neutrophils in peripheral blood in vitro. Three different levels of magnetic induction were analyzed: 10, 40 and 60 μT. Incubation in EMF slightly inhibited activity in unstimulated neutrophils, while activity increased in PMA-stimulated neutrophils after incubation in EMF.
Lai H, Singh NP · 2004
Researchers investigated how magnetic field exposure affected brain cell DNA in rats. Exposure to a 60-Hz magnetic field at 0.01 mT for 24 hours caused a significant increase in DNA single- and double-strand breaks, and prolonging the exposure to 48 hours caused a larger increase. Acute magnetic field exposure also increased apoptosis and necrosis of brain cells in the rat.
Lyskov E, Sandström M, Mild KH · 2001
Researchers investigated possible neurophysiological effects of an intermittent 15 sec on/off cycle, 60 Hz, 10 μT magnetic field on patients with perceived electromagnetic hypersensitivity (EHS) and control subjects during rest and a mental arithmetic task. Magnetic field exposure did not affect autonomic system or electroencephalographic variables in either group. EHS patients and controls showed significant differences in heart rate, heart rate spectrum ratio, and electrodermal activity, while EEG characteristics did not differ between groups.
Joseph W, Goeminne F, Vermeeren G, Verloock L, Martens L. · 2012
Researchers assessed electromagnetic field exposure of workers and the general public from non-directional beacons used for air traffic control. The maximum electric fields exceeded ICNIRP reference levels at all seven sites, and magnetic fields exceeded those levels at two of the seven sites for occupational exposure. The highest measured occupational electric field value was 881.6 V/m and the highest magnetic field value was 9.1 A/m.
Kumari K et al. · 2017
Researchers exposed mice to 7.5 kHz magnetic fields at 12 or 120 μT for 5 weeks. No effects were seen on body weight, spontaneous activity, motor coordination, anxiety, or aggression. In the Morris swim task, the 120 μT group showed a less steep learning curve than other groups. The passive avoidance task revealed a clear memory impairment over 48 hours in the 120 μT group. Hippocampal astroglial activation and neurogenesis were unchanged, while tumor necrosis factor alpha mRNA increased significantly in the 120 μT group.
Liljestrand B, Sandström M, Hansson Mild K. · 2003
The study aimed to investigate RF exposure during use of electrosurgical units. Researchers measured electric fields near the lead wires of two electrosurgical units, a BARD 3000 at 0.5 MHz and an ERBE ICC 350 at 0.3–1 MHz, at distances of 5–30 cm during cutting and coagulating at 10–100 W. The calculated local exposure of the surgeon's hand was estimated to exceed 15 kV/m for the electric field and 16 µT for the magnetic field, exceeding the suggested international reference levels at 0.5 MHz of 610 V/m and 4 µT.
Kumar S et al. · 2013
Researchers exposed rats with spinal cord injuries to extremely low-frequency magnetic fields (50 Hz, similar to power lines) for 2 hours daily over 8 weeks. They found that this exposure helped restore normal pain responses and brain chemistry that had been disrupted by the spinal injuries. The magnetic field treatment appeared to normalize levels of key brain chemicals like serotonin and GABA that control pain perception.
Kumar S, Jain S, Behari J, Avelev VD, Mathur R. · 2010
Researchers studied the effect of magnetic field exposure on food intake, water intake, and body weight in rats with complete spinal cord injury. Exposure ran at 50 Hz and 17.9 T for 2 hours per day over 8 weeks in rats with complete spinal cord transection at the T13 level. The results suggest a significant beneficial effect of chronic exposure to magnetic field of paraplegic rats.
Kumar S, Jain S, Behari J, Avelev VD, Mathur R. · 2010
Researchers exposed rats with spinal cord injuries to extremely low frequency magnetic fields (50 Hz, 17.9 microT) for 2 hours daily over 8 weeks. The magnetic field exposure restored normal food intake, water consumption, and body weight in the paralyzed rats, all of which had decreased after their spinal cord injuries. This suggests that specific magnetic field frequencies might help support basic physiological functions in spinal cord injury patients.
Dey S, Bose S, Kumar S, Rathore R, Mathur R, Jain S. · 2017
Researchers performed complete transection of the spinal cord at the T13 level in male Wistar rats, then exposed them to a magnetic field at 50 Hz and 17.96 µT for 2 hours daily for 8 weeks. Compared to injured rats that received no magnetic field, injured rats that received the magnetic field showed significant improvement in locomotion. Histology, immunohistochemistry, and flow cytometry revealed significant reductions in lesion volume, microglia, macrophage, collagen tissue, and iron content, along with higher vascular endothelial growth factor expression in the magnetic field group.
Kumar S et al. · 2013
Researchers studied the effect of a 50 Hz, 17.96 μT magnetic field on tonic pain behavior and brain neurotransmitters in rats with complete thoracic spinal cord injury at week 8. Adult male Wistar rats were divided into Sham, SCI, and SCI+MF groups, with pain behavior assessed using block pain rating, session pain rating, time spent in pain categories, and flinch counts. Pain ratings and flinch counts were significantly lower in SCI rats than in Sham rats, but these measures were comparable between the SCI+MF and Sham groups. Serotonin was lower in the cortex, remaining forebrain areas, and brainstem, while GABA and norepinephrine were higher in the brainstem of SCI rats, but these levels were comparable to Sham in the SCI+MF group.
Manjhi J, Kumar S, Behari J, Mathur R. · 2013
Researchers studied whether extremely low frequency (ELF) magnetic field exposure could reduce osteoporosis caused by spinal cord injury in rats. Adult male Wistar rats (n = 24) were equally divided into sham, SCI, and SCI+MF groups. Starting one day after injury, the exposed group received ELF magnetic field at 17.96 micro-Tesla and 50 Hz for two hours per day over eight weeks. Bone mineral content, bone mineral density, and biochemical markers were significantly lower in spinal cord injury rats compared with the sham group, and these decreases were attenuated in the magnetic field-treated group, except for carbon content.
Das S, Kumar S, Jain S, Avelev VD, Mathur R. · 2012
Researchers studied the effect of a 50 Hz, 17.96 μT magnetic field on rats after a hemisection injury of the T13 spinal cord, measuring locomotor function, motor responses to noxious stimuli, and neuronal excitability. Rats were divided into a sham-exposed group and a group exposed to the magnetic field for 2 hours per day for 6 weeks. The magnetic-field-exposed group showed a statistically significant improvement in BBB score over the sham control group, and bladder control was dramatically restored earlier than in the sham group. The researchers suggested that this magnetic field exposure promotes recovery of sensori-motor behavior including locomotion and bladder control in spinal-cord-injured rats.
Das S, Kumar S, Jain S, Avelev VD, Mathur R. · 2012
Researchers exposed rats with severe spinal cord injuries to extremely low-frequency magnetic fields (50 Hz at 17.96 μT) for 2 hours daily over 6 weeks. The magnetic field exposure significantly accelerated recovery of motor functions, bladder control, and pain responses compared to untreated injured rats. This suggests that specific EMF exposures might have therapeutic potential for spinal cord injury rehabilitation.
Zhang D, Zhang Y, Zhu B, Zhang H, Sun Y, Sun C · 2017
Researchers enrolled 186 male workers with occupational exposure to high-voltage electricity lines and 154 male subjects with insignificant exposure as a reference control. Resveratrol or placebo was given as dietary supplements at 500 mg twice daily, and inflammatory biomarkers and biomarkers of oxidative stress were assessed. Workers who had long-term exposure to high-voltage electricity lines showed elevated urinary levels of 8-OHdG and F2-isoprostane compared to the reference group. Resveratrol significantly reversed the adverse impacts of ELF-EMF, and stimulated cytokine production by resveratrol was found in exposed workers but not in the reference group.
Azanza MJ et al. · 2013
Researchers exposed pairs of snail neurons to weak 50 Hz magnetic fields (similar to power line frequencies) to see if the fields could synchronize their electrical activity. They found that magnetic fields between 0.2 and 150 Gauss could indeed cause the neurons to fire in synchronized patterns, with stronger fields sometimes disrupting this synchronization. This suggests that extremely low frequency magnetic fields can directly influence how nerve cells communicate with each other.
Azanza MJ et al. · 2013
