Cellular Effects

Exposure to 900 MHz electromagnetic field induces an unbalance between pro-apoptotic and pro-survival signals in T-lymphoblastoid leukemia CCRF-CEM cells

Marinelli F et al. · 2004

Applicability of discovery science approach to determine biological effects of mobile phone radiation.

Leszczynski D, Nylund R, Joenvaara S, Reivinen J. · 2004

The authors argue that high-throughput screening techniques are justified and necessary for studying biological effects of mobile phone radiation. They present the hsp27 protein as an example, suggesting that even modestly altered expression and activity might impact cell physiology. The full evidence is too large for one article and is being prepared for three separate research articles.

Effect of 910-MHz electromagnetic field on rat bone marrow.

Demsia G, Vlastos D, Matthopoulos DP. · 2004

The study aimed to investigate whether 910-MHz electromagnetic fields could be a noxious agent capable of inducing genotoxicity, and rats were exposed daily for 2 h over 30 consecutive days. Researchers examined bone marrow smears from EMF-exposed and sham-exposed animals and observed an almost threefold increase in micronuclei in polychromatic erythrocytes. An induction of micronuclei was also observed in polymorphonuclear cells.

High frequency electromagnetic fields (GSM signals) affect gene expression levels in tumor suppressor p53-deficient embryonic stem cells.

Czyz J et al. · 2004

Researchers exposed wild-type and p53-deficient embryonic stem cells to GSM-217 and GSM-Talk modulated electromagnetic fields at 1.71 GHz. GSM-217 exposure significantly increased hsp70 mRNA levels in p53-deficient cells, with a transient rise in c-jun, c-myc, and p21 levels only in those cells. GSM-Talk exposure produced no gene expression changes in either cell type, and cardiac differentiation and cell cycle were unaffected by GSM-217.

DNA Damage of Lymphocytes in Volunteers after 4 hours Use of Mobile Phone.

Ji S, Oh E, Sul D, Choi JW, Park H, Lee E. · 2004

Researchers used the Comet assay to measure Olive Tail Moment and Tail DNA% in T-cells, B-cells, and granulocytes before and after exposure. Olive Tail Moment and Tail DNA% in B-cells and granulocytes increased significantly after exposure.

Green tea catechins protect rats from microwave-induced oxidative damage to heart tissue.

Kim MJ, Rhee SJ. · 2004

Researchers exposed rats to 2.45 GHz microwave radiation for 15 minutes and then fed them diets containing 0%, 0.25%, or 0.5% catechin. Microwave exposure increased cytochrome P450 levels by 85% and NADPH-cytochrome P450 reductase activity by 29% compared with normal rats. It also raised superoxide radical concentrations by 35% and decreased superoxide dismutase activity by 34% and glutathione peroxidase activity by 28%. Catechin supplementation at 0.25% and 0.5% lowered superoxide radicals by 11% and 12%, increased superoxide dismutase activity by 19% and 25%, and kept glutathione peroxidase near normal.

Ginkgo biloba prevents mobile phone-induced oxidative stress in rat brain

Ilhan A et al. · 2004

Researchers investigated the effect of Ginkgo biloba on mobile phone-induced oxidative damage in rat brain tissue. Mobile phone exposure increased malondialdehyde, nitric oxide, xanthine oxidase, and adenosine deaminase while decreasing superoxide dismutase and glutathione peroxidase activities in brain tissue. Ginkgo biloba treatment prevented these oxidative alterations and the mobile phone-induced cellular injury in brain tissue.

Oxidative stress-mediated skin damage in an experimental mobile phone model can be prevented by melatonin

Ayata A et al. · 2004

Thirty Wistar-Albino rats were assigned to control, irradiated, and irradiated-plus-melatonin groups, and the irradiated group received 900 MHz, 2 W radiation for 30 minutes daily over 10 days. The melatonin group received 10 mg/kg/day melatonin in tap water for 10 days before irradiation. Skin samples were analyzed for malondialdehyde, hydroxyproline, superoxide dismutase, glutathione peroxidase, and catalase. Radiation significantly increased MDA, hydroxyproline, CAT, and GSH-Px and decreased SOD; melatonin reversed the increases in MDA, hydroxyproline, CAT, and GSH-Px but did not prevent the SOD decrease. The results suggest that 900 MHz radiation increases fibrosis and lipid peroxidation in rat skin and that melatonin can reduce these effects.

Influence of extremely-low-frequency magnetic field on antioxidative melatonin properties in AT478 murine squamous cell carcinoma culture.

Zwirska-Korczala K et al. · 2004

Low power microwave radiation inhibits the proliferation of rabbit lens epithelial cells by upregulating P27Kip1 expression.

Yao K, Wang KJ, Sun ZH, Tan J, Xu W, Zhu LJ, Lu de Q. · 2004

Researchers exposed cultured rabbit lens epithelial cells to continuous 2,450 MHz microwave radiation at power densities of 0.10, 0.25, 0.50, 1.00, and 2.00 mW/cm2 for 8 hours. P27Kip1 protein expression increased markedly but its mRNA levels did not change, and P21WAF1 protein and mRNA levels showed no detectable differences between exposed and control groups.

Repeated exposure to low-level extremely low frequency-modulated microwaves affects baseline and scopolamine-modified electroencephalograms in freely moving rats.

Vorobyov V, Pesic V, Janac B, Prolic Z. · 2004

Researchers exposed rats repeatedly for three days to low-intensity 915 MHz microwaves modulated at 4 Hz and recorded EEG from the somatosensory cortex. Microwave exposure alone significantly enhanced fast EEG rhythms (18-30 Hz), an effect not seen in sham-exposed or radiation-naïve rats. In microwave-exposed rats, scopolamine did not cause the EEG slowing observed in non-exposed rats, and its effect resembled that of physostigmine in naive animals.

Blood-forming system in rats after whole-body microwave exposure; reference to the lymphocytes.

Trosic I, Busljeta I, Pavicic I. · 2004

Researchers investigated the effect of 2.45 GHz microwave irradiation on blood-forming cells in rats. Rats were exposed to a field power density of 5-10 mW/cm2 and a whole-body average SAR of 1-2 W/kg for 2 hours a day, 7 days a week, for 2, 8, 15, or 30 days. A significant decrease in lymphoblast count was observed at 15 and 30 days, while other examined parameters did not differ significantly from sham-exposed controls.

Radio frequency radiation effects on protein kinase C activity in rats' brain.

Paulraj R, Behari J · 2004

Protein kinase C activity was measured in whole brain, hippocampus, and whole brain minus hippocampus after exposure. A significant decrease in enzyme level was observed in exposed rats compared to sham-exposed rats.

The production of tumor necrosis factor in cells of tumor-bearing mice after total-body microwave irradiation and antioxidant diet.

Novoselova EG et al. · 2004

Researchers studied effects of weak microwaves (8.15–18 GHz, 1 µW/cm2, 1.5 h daily) and antioxidant diet on TNF production in healthy and tumor-bearing mice. Microwave radiation and antioxidant diet stimulated TNF production in cells from healthy mice. In tumor-bearing mice, microwave exposure increased TNF production compared to unirradiated mice, while antioxidant diet did not affect TNF secretion. Prolonged microwave treatment decreased tumor growth rate and increased longevity in tumor-bearing mice, but antioxidant diet did not.

Acute exposure to GSM 900-MHz electromagnetic fields induces glial reactivity and biochemical modifications in the rat brain

Mausset-Bonnefont AL et al. · 2004

Researchers used a head-only exposure device to expose rats to 900-MHz pulsed microwaves at 6 W/kg for 15 minutes. The exposure induced a strong glial reaction in the brain, particularly in the striatum. Significant immediate effects were observed on the Kd and Bmax values of NMDA and GABA(A) receptors and on dopamine transporters, along with a decrease in NMDA receptors at the postsynaptic membrane. General locomotor behavior was not significantly altered in the short term.

Apoptosis induced by ultraviolet radiation is enhanced by amplitude modulated radiofrequency radiation in mutant yeast cells.

Markkanen A et al. · 2004

Researchers exposed wild-type and cdc48-mutant yeast cells to 900 or 872 MHz RF fields with or without UV radiation at elevated temperature. Amplitude modulated RF exposure significantly enhanced UV-induced apoptosis in cdc48-mutated cells, but unmodulated fields at the same SAR had no effect. Apoptosis was measured using the annexin V-FITC method with flow cytometry.

Non-thermal effects of electromagnetic fields at mobile phone frequency on the refolding of an intracellular protein: myoglobin.

Mancinelli F et al. · 2004

Researchers exposed tuna myoglobin solutions at pH 3.0 to a 1.95 MHz microwave field for 3 hours at a specific absorption rate of 51±1 mW/g. They monitored heme site refolding by measuring molecular absorption in the Soret spectral region and fitted the data to a bi-exponential model. The kinetics of exposed samples appeared slowered by the microwave field. The tryptophanyl lifetime distribution of the exposed protein appeared sharper than that of non-exposed samples. The researchers suggested that microwave fields could affect the propensity of myoglobin molecules to populate specific conformational substates and alter aggregation during folding, representing a potential misfolding risk.

Effects of 2.45-GHz electromagnetic fields with a wide range of SARs on micronucleus formation in CHO-K1 cells.

Koyama S, Isozumi Y, Suzuki Y, Taki M, Miyakoshi J. · 2004

Researchers exposed Chinese hamster ovary CHO-K1 cells to 2.45-GHz electromagnetic fields for 2 hours at SARs of 5, 10, 20, 50, 100, and 200 W/kg to study micronucleus formation. Micronucleus frequency in cells exposed at SARs lower than 50 W/kg did not differ from sham-exposed controls. At SARs of 100 and 200 W/kg, micronucleus frequency was significantly higher than in sham-exposed controls. The researchers also found that micronucleus frequency increased in a temperature-dependent manner when cells were heat-treated at temperatures from 38 to 42 degrees C.

Influence of anesthesia on ocular effects and temperature in rabbit eyes exposed to microwaves.

Kojima M et al. · 2004

Researchers exposed one eye each of 43 male pigmented rabbits to microwaves at 300 mW/cm2, either under systemic anesthesia or without anesthesia. Exposed eyes showed miosis, conjunctival congestion, corneal edema, and increased light scattering in the lens, and all of these anterior ocular changes disappeared within a week. Rabbits under systemic anesthesia showed much stronger symptoms, and their ocular temperatures were 2-9 degrees C higher than those without anesthesia.

In vitro exposure of human lymphocytes to 900 MHz CW and GSM modulated radiofrequency: studies of proliferation, apoptosis and mitochondrial membrane potential.

Capri M et al. · 2004

Researchers exposed human peripheral blood mononuclear cells (PBMCs) from healthy donors in vitro to a 900 MHz GSM or continuous-wave (CW) radiofrequency field for 1 hour per day for 3 days. The researchers studied mitogen-induced proliferation, cell cycle progression, spontaneous and induced apoptosis, and mitochondrial membrane potential. GSM-exposed cells showed a slight decrease in proliferation at the lowest mitogen concentration and a slight increase in cells with altered phosphatidylserine distribution, but cell cycle phases, mitochondrial membrane potential, and susceptibility to apoptosis were unaffected. When cells were exposed to the CW radiofrequency field, no significant modifications were observed for any of the endpoints studied.

The effects of whole body cell phone exposure on the t1 relaxation times and trace elements in the serum of rats.

Aksen F, Dasdag S, Akdag MZ, Askin M, Dasdag MM. · 2004

Researchers exposed rats to radiofrequency radiation from cellular phones to study effects on trace elements, T1 relaxation times, and rectal temperature. Manganese and zinc levels in the serum of exposed rats were significantly different from the control group. Iron, copper, and T1 relaxation times in serum did not change significantly, and rectal temperature also showed no statistically significant difference between groups.

Acute exposure to 930 MHz CW electromagnetic radiation in vitro affects reactive oxygen species level in rat lymphocytes treated by iron ions.

Zmyslony M, Politanski P, Rajkowska E, Szymczak W, Jajte J. · 2004

Researchers tested whether 930 MHz continuous wave electromagnetic radiation affects reactive oxygen species (ROS) levels in rat lymphocytes. Acute exposure of 5 and 15 minutes did not affect ROS levels on its own. When iron ions were added to stimulate ROS production, the ROS level was significantly greater in exposed lymphocytes after both exposure durations.

Effects of in vitro exposure to power frequency magnetic fields on UV-induced DNA damage of rat lymphocytes.

Zmyślony M et al. · 2004

The effect of weak 50 Hz magnetic fields on the number of free oxygen radicals in rat lymphocytes in vitro

Zmyslony M, Rajkowska E, Mamrot P, Politanski P, Jajte J · 2004

Researchers tested whether weak 50 Hz magnetic fields affect the number of free oxygen radicals in rat lymphocytes in vitro. Rat lymphocytes were exposed for one hour to 50 Hz magnetic fields at 20, 40, or 200 μT, with the field axis either along or crosswise to Earth's static magnetic field. Only at 40 μT, when the field was directed along Earth's static magnetic field, was there a decrease in fluorescence compared to non-exposed samples.

Fifty-hertz magnetic fields induce free radical formation in mouse bone marrow-derived promonocytes and macrophages.

Rollwitz J, Lupke M, Simkó M · 2004

Researchers studied the effects of 50 Hz magnetic fields on free radical production in mouse bone marrow-derived macrophages and monocytes. Exposure to the magnetic fields at a flux density of 1 mT produced a significant increase in free radical production in both cell types. The radicals produced were mainly superoxide anion radicals, found in macrophages at 33% and in their precursor cells at 24%.