Furtado-Filho OV et al. · 2015
Researchers exposed young rats to 950 MHz ultra-high-frequency electromagnetic radiation to measure oxidative damage to DNA, proteins, and lipids in the left and right cerebral cortex. Radiation exposure lasted 30 minutes per day for up to 27 days, with a specific absorption rate ranging from 1.32 to 1.14 W/kg. In neonates, no modification of the biomarkers tested was detected, while 6-day-old exposed rats showed increased carbonylated proteins in the right cerebral cortex and decreased blood glucose. The researchers concluded that the elevated carbonylated proteins in the right cerebral cortex did not appear to be a consequence of oxidative stress.
Eris AH et al. · 2015
Researchers exposed ten male Wistar Albino rats to 900 MHz electromagnetic radiation at 15.14 V/m for 45 minutes and measured blood serotonin and glutamate levels before and after. Blood plasma serotonin and glutamate levels were measured using enzyme immunoassay. A single 45-minute exposure significantly increased blood serotonin levels but did not change glutamate levels.
Zhao QR, Lu JM, Yao JJ, Zhang ZY, Ling C, Mei YA. · 2015
Researchers used a mouse model to examine the effects of extremely low-frequency (50 Hz) electromagnetic field exposure on a recognition memory task and morphological changes of hippocampal neurons. Exposure at 1 mT for 12 hours per day produced a time-dependent deficit in novel object associative recognition memory and decreased hippocampal dendritic spine density. The memory deficit was transient, observed only after exposing mice to the fields for 7 to 10 days, and occurred without changes in spontaneous locomotor activity. Over-expression of neuritin in the hippocampus using an adeno-associated virus vector significantly increased neuritin levels and dendritic spine density, and neuritin prevented the exposure-induced effect by increasing hippocampal spine density.
Yang G, Ren Z, Mei YA. · 2015
Researchers studied the effects of 50 Hz magnetic fields on GABAA receptor activity in rat cerebellar granule neurons. Exposing the neurons to 1 mT of the field for 60 minutes significantly increased GABAA receptor currents without modifying sensitivity to GABA. Levels of phosphorylated PKC were significantly elevated after 60 minutes of exposure, and this elevation was blocked by an EP1 receptor-specific antagonist.
Liu X et al. · 2015
Researchers studied the effects of ELF-EMF exposure on Alzheimer's disease development in rats. The rats were exposed to ELF-EMF at 50 Hz and 400 µT for 60 days. ELF-EMF exposure delayed the weight gain of rats and partially improved cognitive and clinicopathologic symptoms. The researchers concluded that certain conditions of ELF-EMF exposure could delay the development of AD in rats.
Giorgetto C et al. · 2015
Researchers studied motor behaviour in Wistar rats given a unilateral striatal lesion with quinolinic acid, then injected with apomorphine and exposed to a continuous static magnetic field of 3,200 Gauss. Sixty-eight male Wistar rats were divided into six groups: control, sham, sham magnetic, lesion, and stimulated South and North Poles. In the activity cage test, all groups except the North Pole-stimulated group showed a significant increase in distance, time of activity, and crossings compared to the control group. The morphometric analysis showed a reduction in the number of neurons in the Lesion group in relation to all other groups, and the results suggest the static magnetic field promoted morphological preservation.
de Groot MW, van Kleef RG, de Groot A, Westerink RH · 2015
Researchers exposed primary rat cortical neurons for 7 days to 50 Hz ELF-EMF at field strengths ranging from 0 to 1000 μT, then measured cell viability, calcium levels, neurite outgrowth, and spontaneous neuronal activity. Cell viability was not affected by exposure across the full range tested, and neuronal activity appeared largely unaltered. The researchers concluded that chronic ELF-EMF exposure has only limited neurotoxic potential in vitro.
Zuo WQ, Hu YJ, Yang Y, Zhao XY, Zhang YY, Kong W, Kong WJ. · 2015
Researchers used spiral ganglion neurons from neonatal Sprague Dawley rats to investigate whether inflammation might increase sensitivity to damage from mobile phone electromagnetic radiation. Radiofrequency electromagnetic radiation alone could not directly induce DNA damage in normal spiral ganglion neurons. The study suggests that sensitivity of spiral ganglion neurons to damage caused by mobile phone electromagnetic radiation may increase in a lipopolysaccharide-induced inflammation model.
Hou Q, Wang M, Wu S, Ma X, An G, Liu H, Xie F · 2015
Researchers studied reactive oxygen species, DNA damage, and apoptosis in mouse embryonic fibroblasts (NIH/3T3) exposed to 1800-MHz GSM-talk mode electromagnetic radiation at an average specific absorption rate of 2 W/kg. Intracellular ROS levels increased significantly after exposure, reaching their highest level at one hour of exposure, then declining slightly with longer exposure up to eight hours. The percentage of late-apoptotic cells was significantly higher in the exposed group than in sham-exposed groups, while no significant effect on the DNA damage marker γH2AX was detected.
Duan W et al. · 2015
Researchers exposed a mouse spermatocyte-derived GC-2 cell line intermittently to 50 Hz ELF-EMF at intensities of 1, 2, or 3 mT, or to 1800 MHz RF-EMF in GSM-Talk mode at SAR values of 1, 2, or 4 W/kg. After 24 hours of exposure, neither ELF-EMF nor RF-EMF affected cell viability. ELF-EMF exposure significantly increased DNA strand breaks at 3 mT, while RF-EMF exposure significantly induced oxidative DNA base damage at a SAR of 4 W/kg. The researchers suggest that both field types may produce genotoxicity at relatively high intensities but through different patterns of DNA damage.
Djordjevic B et al. · 2015
Researchers studied whether melatonin treatment (2 mg/kg) might favorably impact liver tissue in rats exposed to microwave radiation. The experiment used 84 six-weeks-old Wistar male rats exposed for 4 hours a day to microwaves at 900 MHz for 20, 40, and 60 days. Microwave exposure increased malondialdehyde after 40 days, protein carbonyl content after 20 days, and catalase and xanthine oxidase activity after 40 days. Melatonin reduced malondialdehyde after 40 days but had no effect on the other analyzed parameters.
Cao H, Qin F, Liu X, Wang J, Cao Y, Tong J, Zhao H · 2015
Researchers exposed male Sprague Dawley rats to 1.8 GHz radiofrequency fields at different times of day to study whether circadian rhythms of plasma antioxidants were affected. Six groups of animals were exposed at a power density of 201.7 μW/cm2 and a specific absorption rate of 0.05653 W/kg for 2 hours per day for 32 consecutive days, each at a different time of day, while a seventh group served as sham-exposed controls. The circadian rhythms of melatonin, GSH-Px, and SOD were shifted in exposed rats, with levels significantly decreased when exposure was given at 23 and 3 h GMT. The researchers concluded that there may be adverse effects of radiofrequency exposure on antioxidant function, affecting both daily antioxidant levels and circadian rhythmicity.
Ghodbane S, Lahbib A, Ammari M, Sakly M, Abdelmelek H. · 2015
Researchers exposed rats to a static magnetic field at 128 mT for one hour per day over five days and measured catalase activity, malondialdehyde concentration, and apoptosis inducing factor labeling in kidney and muscle. SMF exposure increased MDA concentrations by 25% and CAT activities by 34% in kidney, but not in muscle. The treatment failed to induce caspase-independent pathway apoptosis in both kidney and muscle. Selenium pre-treatment inhibited both the MDA and CAT increases in kidney, while vitamin E corrected only MDA levels in rat kidney.
Ghodbane S, Ammari M, Lahbib A, Sakly M, Abdelmelek H. · 2015
Researchers exposed rats to a static magnetic field of 128 mT for one hour per day over five consecutive days and measured oxidative stress and apoptosis in the brain and liver. The exposure increased catalase activity by 24% in the liver but not in the brain, while malondialdehyde concentration was unchanged in both tissues. Static magnetic field exposure also induced hepatocyte apoptosis through a caspase-independent pathway involving mitochondrial apoptosis-inducing factor, but no such effect was found in the brain. Selenium and vitamin E supplementation restored liver catalase activity in exposed rats but did not reduce liver apoptosis.
Chung YH et al. · 2015
Researchers exposed rats to an extremely low frequency magnetic field at 60 Hz and 2.0 mT for 2 or 5 days, then measured neurotransmitter levels in the cortex, striatum, thalamus, cerebellum and hippocampus. The exposure produced significant differences in norepinephrine and vanillyl mandelic acid in the striatum, thalamus, cerebellum and hippocampus. Significant increases in serotonin and 5-hydroxyindoleacetic acid were observed in the striatum, thalamus or hippocampus, and dopamine concentration was significantly increased in the thalamus. The researchers concluded that exposure to ELF-MF may evoke changes in these brain chemicals, though the mechanisms remain to be characterized.
Zhang Y, Li Z, Gao Y, Zhang C. · 2015
Researchers investigated whether in utero exposure to 9.417-GHz microwave throughout gestation affected behavior in mouse offspring. Offspring showed less movement in the center of an open field and in an open arm of the elevated-plus maze, which the researchers interpreted as increased anxiety-related behavior. Offspring also showed reduced immobility in the tail suspension test and forced swimming test, which was interpreted as decreased depression-related behavior. In the Morris water maze, male offspring showed decreased learning and memory while female offspring were not affected, suggesting gender-dependent effects.
Xiong L et al. · 2015
Researchers exposed 48 male Wistar rats to 30 mW/cm2 microwave for 10 min every other day for three times, and separately exposed PC12 cells to 30 mW/cm2 microwave for 5 min. Microwave exposure caused injury in rat hippocampal structure and PC12 cells, especially the structure and quantity of synapses. The ratio of glutamic acid and gamma-aminobutyric acid neurotransmitters was increased and the intracellular calcium level was elevated in PC12 cells. Significant changes in NMDA receptor subunits NR1, NR2A, and NR2B and related signaling molecules were observed, and these were closely associated with impaired synaptic plasticity.
Wang LF et al. · 2015
Researchers used an in vitro blood-brain barrier model exposed to microwave radiation at 50 mW/cm2 for 5 minutes to study how the VEGF/Flk-1-ERK pathway relates to barrier injury. Microwave radiation caused tight junctions to broaden and fracture, with decreased TEER values and increased HRP permeability. When Flk-1 and MEK1/2 inhibitors were applied, the structure and function of the blood-brain barrier were recovered.
Tang J et al. · 2015
Researchers exposed 108 male Sprague-Dawley rats to a 900 MHz, 1 mW/cm2 electromagnetic field for 14 or 28 days at 3 hours per day, with some rats left unexposed as a sham group. Rats exposed for 28 days crossed platforms less often and spent less time in the target quadrant than rats exposed for 14 days and unexposed rats. Twenty-eight days of exposure was also associated with cellular edema, neuronal cell organelle degeneration, and albumin and HO-1 extravasation in the hippocampus and cortex. The researchers found that 28 days of EMF exposure induced the expression of mkp-1, resulting in ERK dephosphorylation.
Narayanan SN, Kumar RS, Karun KM, Nayak SB, Bhat PG · 2015
Megha K et al. · 2015
Researchers exposed Fischer rats to 900 MHz and 1800 MHz microwave radiation for 30 days at 2 hours per day, 5 days per week, with specific absorption rates of 5.953 × 10−4 and 5.835 × 10−4 W/kg respectively. Levels of dopamine, norepinephrine, epinephrine, and serotonin were measured in the hippocampus using LC–MS/MS. Exposed animals showed significant reductions in DA, NE, E and 5-HT, and significant downregulation in mRNA expression of TH, TPH1, and TPH2 compared with sham-exposed animals (p < 0.05).
Deshmukh PS et al. · 2015
Researchers exposed male Fischer rats to microwave radiation for 180 days at 3 different frequencies, namely, 900, 1800 MHz, and 2450 MHz. The study investigated effects on cognitive function, heat shock protein 70 (HSP70), and DNA damage in rat brain. The results showed declined cognitive function, elevated HSP70 level, and DNA damage in the brains of microwave-exposed animals. The researchers concluded that chronic low-intensity microwave exposure in the frequency range of 900 to 2450 MHz may cause hazardous effects on the brain.
Bodera P et al. · 2015
Researchers measured malondialdehyde (MDA), a marker of lipid peroxidation, in the blood, liver, kidneys, and brain of Wistar rats that were healthy or had inflammation, and exposed them repeatedly to 1800 MHz EMF. The exposure was repeated five times for 15 minutes and was studied both alone and combined with the opioid painkiller tramadol. MDA levels were slightly elevated in the blood, kidney, and brain of healthy rats in EMF-exposed groups treated with tramadol, while MDA in the liver remained at the same level across all groups. Overall, results for healthy rats and animals with inflammation did not differ significantly.
Unknown authors · 2014
Researchers studied the combined effects of extremely high-frequency EMR and X-rays on DNA damage in mouse whole blood leukocytes. Pulse-modulated EHF EMR at 42.2 GHz with 0.1 mW/cm2 power density for 20 minutes induced hydrogen peroxide at 4.6 ± 0.3 nM L−1. Exposure to this pulse-modulated EMR 25 minutes before 4 Gy X-rays reduced ionizing radiation-induced DNA damage. Continuous EHF EMR was inefficient. Low-level hydrogen peroxide (30–500 nM L−1) also protected cells against X-irradiation.
Unknown authors · 2014
Researchers exposed adult mice to continuous 50 Hz magnetic fields at 0.1 mT or 1.0 mT for eight weeks. They found no evidence of increased persistent unrepaired nuclear DNA single-strand breaks in distinct cell types of the brain, kidney, and liver.
