Gapeyev AB, Aripovsky AV, Kulagina TP. · 2014
Researchers studied whether extremely high-frequency electromagnetic radiation (EHF EMR) could modify fatty acid content and composition in the thymus of mice also exposed to X-rays. Mice were exposed to low-intensity pulse-modulated EHF EMR at 42.2 GHz and/or X-rays at a dose of 4 Gy, with measurements taken at several time points up to 40 days after exposure. X-irradiation alone significantly increased total fatty acid content in thymic tissue within 4 to 5 hours and decreased it at 10 and 30 days, while thymus weight remained significantly reduced on days 30 and 40. When EHF EMR was applied before or after X-irradiation, changes in total fatty acid content were prevented and thymus weight restoration was promoted by day 40.
Zong C, Ji Y, He Q, Zhu S, Qin F, Tong J, Cao Y. · 2014
Researchers exposed adult mice to 900 MHz radiofrequency fields at 120 μW/cm2 power density for 4 hours per day for 7 days, then injected some mice with bleomycin. Radiofrequency exposure alone showed no indications of increased DNA or oxidative damage compared to mice treated with bleomycin alone. Mice exposed to radiofrequency fields and then given bleomycin showed significantly reduced DNA damage at each repair time point measured, as well as decreased MDA levels and increased SOD levels.
Türedi S et al. · 2014
Researchers exposed pregnant rats to a 900 MHz electromagnetic field for one hour per day on days 13 to 21 of pregnancy, then examined the hearts of male rat pups on postnatal day 21. The mean electrical field intensity inside the exposure box was 13.77 V/m. In the exposed group, malondialdehyde, superoxide dismutase, and catalase values were significantly higher, while glutathione values were lower. Microscopy revealed irregularities in heart muscle fibers, apoptotic changes, mitochondrial swelling and crista loss, myofibril degeneration, and structural impairments in Z bands.
Shahin S, Mishra V, Singh SP, Chaturvedi CM. · 2014
Researchers exposed twelve-week-old male Swiss strain mice to 2.45-GHz microwave radiation for 2 hours per day for 30 days at a power density of 0.029812 mW/cm2 and SAR of 0.018 W/Kg. Microwave irradiation induced a significant decrease in sperm count and sperm viability, along with a decrease in seminiferous tubule diameter and degeneration of seminiferous tubules. Reduced testicular 3β HSD activity and plasma testosterone levels were also observed in the exposed mice. The researchers suggested that chronic exposure to nonionizing microwave radiation may lead to infertility via a free radical species-mediated pathway.
Sefidbakht Y et al. · 2014
Researchers exposed HEK293T cells carrying a firefly luciferase gene to 940 MHz RF-EMF at a mean specific absorption rate of approximately 0.09 W kg-1. The effects of exposure durations of 15, 30, 45, 60 and 90 minutes on luciferase activity and oxidative response elements were investigated. Luciferase activity was reduced after 30 and 45 minutes of continuous exposure, while after 60 minutes the exposed cells showed higher luciferase activity compared with non-exposed controls. ROS generation was highest in the 30-minute exposed cells, followed by a sharp rise in catalase and superoxide dismutase activity and elevation of glutathione during the 45-minute exposure.
Ozgur E et al. · 2014
Researchers exposed adult male guinea pigs to GSM-modulated radio frequency radiation at an average whole body SAR of 0.4 W/kg for 10 or 20 minutes daily for seven consecutive days. The study measured protein oxidation, advanced oxidation protein products, and superoxide dismutase activity in liver tissue, and also tested NAC and EGCG as potential protective treatments. SOD activity significantly decreased after radio frequency radiation exposure, but protein damage did not change. NAC treatment alone increased PCO levels, and EGCG treatment alone elevated AOPP levels.
Meena R, Kumari K, Kumar J, Rajamani P, Verma HN, Kesari KK. · 2014
Researchers divided 70-day-old male Wistar rats into four groups: sham exposed, melatonin treated, microwave exposed, and microwave plus melatonin treated. Exposure took place in Plexiglas cages for 2 hours a day for 45 days at a power density of 0.21 mW/cm2 and a SAR of 0.14 W/Kg. Melatonin was associated with a significant increase in testicular LDH-X and decreased levels of MDA and ROS in the testes. The researchers concluded that melatonin has strong antioxidative potential against microwave-induced oxidative stress mediated DNA damage in testicular cells.
Manta AK, Stravopodis DJ, Papassideri IS, Margaritis LH. · 2014
Researchers measured reactive oxygen species (ROS) levels in the bodies and ovaries of 4-day-old Drosophila melanogaster flies after exposing them to DECT base radiation at 1.88–1.90 GHz. Male and female bodies showed a twofold increase in ROS levels after 6 hours of exposure, with ROS levels returning to normal 24 hours after that exposure ended. Ovaries responded more quickly, reaching a 2.5-fold ROS increase after 1 hour of exposure, with levels returning to normal 4 hours after that exposure ended.
Liu K et al. · 2014
Researchers exposed mouse spermatocyte-derived cells (GC-2) to 1800 MHz GSM signals at SAR values of 1, 2, or 4 w/kg for 24 hours. The expression of LC3-II increased in a dose- and time-dependent manner with RF exposure, and showed a significant change at the SAR value of 4 w/kg. RF exposure did not increase the percentage of apoptotic cells, but inhibition of autophagy could increase the percentage of apoptotic cells. The findings suggested that autophagy flux could be enhanced by 1800 MHz GSM exposure, mediated by ROS generation.
Gürler HS, Bilgici B, Akar AK, Tomak L, Bedir A. · 2014
Researchers studied oxidative damage and the protective effect of garlic in rats exposed to low-level electromagnetic fields at 2.45 GHz microwave radiation. Groups II and III were exposed to low-level EMF at 3.68 ± 0.36 V/m at 2.45 GHz for 1 hour/day for 30 consecutive days, with Group III also receiving 500 mg/kg garlic daily. Exposure increased 8-OHdG levels in both plasma and brain tissue and increased AOPP levels only in plasma, while garlic prevented the increase of 8-OHdG in brain tissue and AOPP in plasma.
Abu Khadra KM, Khalil AM, Abu Samak M, Aljaberi A. · 2014
Researchers evaluated biochemical parameters in the saliva of 12 young males before and after using a mobile phone. The phone emitted radio frequency signals of 1800 MHz with a 1.09 w/kg specific absorption rate, and participants used it for 15 and 30 minutes. SOD levels followed a quadratic trend, rising after 15 minutes of talking but then dropping as talking time increased. The researchers suggested that exposure to electromagnetic radiation may exert an oxidative stress on human cells, as evidenced by the increase in the concentration of the superoxide radical anion released in the saliva of cell phone users.
Seifirad S et al. · 2014
Single exposure significantly increased lipid peroxidation and also increased antioxidant serum activity, including HDL, paraoxonase activity, and serum total antioxidant capacity. Chronic exposure increased lipid peroxidation, affected the antioxidant system, and led to irreversible changes, while acute exposure tended toward reversible alterations. The researchers noted that antioxidant capability was dependent on the duration and continuity of ELF-MF exposure.
Pandir D, Sahingoz R · 2014
Researchers exposed Mediterranean flour moth (Ephestia kuehniella) larvae to a 1.4-Tesla magnetic field at 50 Hz for time periods ranging from 3 to 72 hours. DNA damage, measured by the comet assay, was significantly larger than in the control group at increasing exposure times. Antioxidant enzyme activities (SOD, CAT, GPx, and GST) decreased and the lipid peroxidation marker MDA increased in exposed larvae compared to controls.
Luukkonen J, Liimatainen A, Juutilainen J, Naarala J · 2014
Researchers exposed human SH-SY5Y neuroblastoma cells to a 50-Hz, 100-μT magnetic field for 24 hours, followed by a 3-hour exposure to menadione. The study aimed to investigate cellular changes occurring during the first 24 hours of magnetic field exposure and whether those changes could lead to genomic instability in the progeny of exposed cells. Magnetic field exposure was associated with increased micronuclei at 8 and 15 days after exposure, increased mitochondrial activity at 8 days, and increased reactive oxygen species production and lipid peroxidation at 15 days. The researchers suggest that magnetic field exposure disturbs oxidative balance immediately after exposure, and that persistently elevated levels of micronuclei were found in the progeny of exposed cells.
Ghodbane S1 et al. · 2014
Researchers exposed rats to a static magnetic field of 128 mT for one hour per day over five days and examined effects on glucose metabolism. Exposure increased blood glucose level by 21% and caused a decrease of 15% in liver glycogen content. Vitamin E prevented the glucose metabolism and liver glycogen alterations induced by the static magnetic field, whereas selenium restored only liver glycogen content. Neither vitamin E nor selenium corrected the reduction in pancreatic islet area observed after static magnetic field exposure.
Deng B et al. · 2014
Researchers investigated the effects of sevoflurane on brain injury caused by electromagnetic pulse (EMP) exposure in rats and in cultured neurons. Rats were exposed to EMP and immediately treated with sevoflurane, and their brain tissue and behavior were assessed. Sevoflurane alleviated neuronal abnormalities in the cerebral cortex and reduced learning and memory deficits caused by EMP exposure. In cell experiments, EMP exposure reduced cell viability and increased LDH release, and sevoflurane treatment ameliorated these effects.
Ciejka E et al. · 2014
Researchers studied how an extremely low frequency magnetic field used in magnetotherapy affected glutathione levels and redox state in rat skeletal muscle. Male rats weighing 280-300 g were randomly divided into 3 experimental groups: a control group and treatment groups exposed to 40 Hz, 7 mT for either 0.5 h/day or 1 h/day for 14 days. Both 30 min/day and 60 min/day exposures significantly increased total glutathione levels in skeletal muscle compared to controls (p < 0.001).
Chen Y, Hong L, Zeng Y, Shen Y, Zeng Q. · 2014
Researchers exposed mouse embryonic fibroblasts to a 50 Hz power frequency magnetic field at 2 mT across several time points and measured autophagy markers. A significant increase in autophagic markers was observed at 6 hours, including higher LC3-II levels, increased GFP-LC3 puncta formation, and increased numbers of autophagic vacuoles. The increase in autophagic markers was the result of enhanced autophagic flux and not the suppression of lysosomal function, and the autophagic process involved reactive oxygen species and was independent of the mTOR signaling pathway.
Reale M et al. · 2014
Researchers evaluated the effects of an electromagnetic wave at a magnetic field intensity of 1 mT and a frequency of 50-Hz on human SH-SY5Y cells, a well-characterized immortalized neuronal cell model. ELF-EMF exposure elevated the expression of NOS and O2−, which were countered by compensatory changes in antioxidant catalase activity and enzymatic kinetic parameters related to CYP-450 and CAT activity. Cytokine gene expression was additionally evaluated and found rapidly modified by ELF-EMF exposure. When co-exposed to H2O2-induced oxidative stress, ELF-EMF proved not as well counteracted, resulting in a decline in CAT activity and a rise in O2− levels.
Rauš Balind S, Selaković V, Radenović L, Prolić Z, Janać B. · 2014
Researchers studied whether an extremely low frequency magnetic field (ELF-MF, 50 Hz, 0.5 mT) affects oxidative stress in the brains of gerbils submitted to 10-min global cerebral ischemia. After occlusion of both carotid arteries, 3-month-old gerbils were continuously exposed to ELF-MF for 7 days, and oxidative stress markers were measured in the forebrain cortex, striatum and hippocampus. Ischemic gerbils exposed to ELF-MF showed increased oxidative stress on the 7th day after reperfusion, but to a lesser extent than ischemic or ELF-MF-exposed animals alone, and by the 14th day their oxidative stress parameters were mostly at control levels. The results indicate a beneficial effect of ELF-MF (50 Hz, 0.5 mT) in the model of global cerebral ischemia.
Manikonda PK et al. · 2014
Researchers exposed male Wistar rats to extremely low frequency magnetic fields at 50 Hz, at intensities of 50 and 100 µT, for 90 days continuously. The hippocampal, cerebellar and cortical regions of the brain were analyzed for reactive oxygen species, markers of oxidative stress, and antioxidant enzymes. Compared with control rats, exposed rats showed oxidative stress and altered glutathione levels in a dose-dependent manner across all brain regions.
Kantar Gok D et al. · 2014
Researchers used ninety male rats, aged 3 months, to investigate how different intensities and durations of extremely low-frequency electric fields affected brain responses and oxidative damage. Rats were exposed to 12-kV/m and 18-kV/m electric fields for 2 or 4 weeks, and mismatch negativity (MMN) responses were recorded in anesthetized rats using electrodes placed on the dura. MMN amplitude was significantly decreased in the E18-4 group compared with the C4 group, and 4-HNE was increased in all experimental groups compared with the control group. The researchers concluded that the electric field decreased MMN amplitudes, possibly induced by lipid peroxidation.
Giorgi G et al. · 2014
Researchers investigated whether pulsed magnetic field exposure could interfere with DNA damage and repair in human neuroblastoma BE(2)C cells under oxidative stress. Cells were treated with hydrogen peroxide and exposed to a pulsed magnetic field at 1 mT and 50 Hz, and DNA double strand breaks were tracked using gamma-H2AX foci formation at 1, 24, 48, and 72 hours after treatment. The results suggest that pulsed magnetic field exposure does not interfere with genotoxicity and cytotoxicity induced by oxidative stress.
Qin F, Yuan H, Nie J, Cao Y, Tong J · 2014
Researchers exposed male mice to 1800 MHz radiofrequency fields at 208 microW/cm2 for 0, 30, or 120 minutes per day for 30 days, while some groups also received nano-selenium by intra-gastric injection. Significant impairments in learning and memory were observed in the RF 120 min group, along with reduced acetylcholine levels and antioxidant enzyme activity and increased GABA, glutamate, and MDA in the brain. Nano-selenium supplementation decreased GABA, glutamate, and MDA levels and increased acetylcholine levels and antioxidant enzyme activities in the exposed mice.
Narayanan SN, Kumar RS, Kedage V, Nalini K, Nayak S, Bhat PG · 2014
Researchers studied the effects of 900 MHz radio-frequency electromagnetic radiation on oxidant stress and antioxidant defense in discrete brain regions of adolescent rats. Thirty-six male Wistar rats aged 6 to 8 weeks were divided into a control group, a sham group, and an RF-EMR-exposed group, with 12 animals in each group. The exposed group received 900 MHz RF-EMR at a peak power density of 146.60 µW/cm2 for one hour per day for four weeks from an activated GSM mobile phone. Elevated TBARS levels were found in all brain regions studied, and altered behavioral performances were found in RF-EMR-exposed rats.
