Musaev AV, Ismailova LF, Gadzhiev AM. · 2005
Researchers studied changes in ascorbate- and NADPN2-dependent induced lipid peroxidation in the visual analyzer and hypothalamus of 3- and 12-month-old rats exposed to high- and low-intensity microwaves. High-intensity exposure stimulated basal LPO but suppressed LPO-inducing systems. Low-intensity exposure activated induced LPO systems accompanied by synchronous antioxidant defense activity maintaining redox balance. The authors concluded that microwaves can be either beneficial or a factor of oxidative stress depending on intensity.
Caraglia M et al. · 2005
Researchers exposed human epidermoid cancer KB cells to non-thermal microwave electromagnetic fields at 1.95 MHz. The exposure induced time-dependent apoptosis reaching 45% after 3 hours, accompanied by a roughly 2.5-fold decrease in expression of ras and Raf-1 and activity of ras and Erk-1/2. A 2.5-fold increase in ubiquitination of ras and Raf-1 was observed, and proteasome inhibition with lactacystin counteracted the degradation, indicating proteasome-dependent degradation. MW-EMF differentially activated stress pathways, increasing JNK-1 activity and HSP70 and HSP27 expression while reducing p38 kinase activity and HSP90 expression; overexpression of HSP90 completely blocked apoptosis and the inactivation of the ras-Erk survival signal, while Erk inhibition reversed this protection.
Anghileri LJ, Mayayo E, Domingo JL, Thouvenot P. · 2005
Mice were treated with 1 hour per week of radiofrequency exposure for 4 months while a sham-exposed group served as controls. The evolution of carcinogenesis was followed up to 18 months, and the maximal life span of control mice was about 24 months. All dead animals were clinically and histologically examined to give an age-determined comparative quantification of the evolving carcinogenesis. A radiocalcium tracer method permitted the evaluation of radiofrequency effects on transmembrane transport of extracellular calcium at 1 and 24 hours after exposure, and the determination of induced lipid peroxidation completed this second study.
Yariktas M et al. · 2005
Ozguner F et al. · 2005
Researchers exposed rats to 900 MHz EMR radiation for 30 minutes per day over 10 days and measured oxidative stress markers and antioxidant enzyme activities. Exposure increased MDA and NO levels and decreased SOD, CAT, and GSH-Px activities in myocardial tissue. Treatment with CAPE reversed these changes, indicating a protective effect against mobile phone-induced oxidative heart injury.
Ozguner F et al. · 2005
The study compared the protective effects of melatonin and CAPE against 900 MHz mobile phone radiation-induced renal tubular injury in rats. Exposure increased urinary NAG and renal MDA levels in rats. Both melatonin and CAPE significantly reduced these elevated markers. Melatonin also increased SOD and GSH-Px activities above control levels, while CAPE did not increase these enzymes.
Ozguner F, Oktem F, Ayata A, Koyu A, Yilmaz HR. · 2005
Oktem F, Ozguner F, Mollaoglu H, Koyu A, Uz E. · 2005
Researchers exposed rats to 900-MHz mobile phone radiation for 30 minutes daily over 10 days. Exposure increased kidney tissue malondialdehyde and urine N-acetyl-beta-d-glucosaminidase while decreasing superoxide dismutase, catalase, and glutathione peroxidase activities. Melatonin administered before each exposure reversed these changes. The authors concluded that melatonin may protect against mobile phone-induced kidney impairment in rats.
Regoli F et al. · 2005
Buczyński A et al. · 2005
Researchers exposed human blood platelets to electromagnetic fields characteristic of car environments. Free radical generation increased after 30 and 90 minutes of exposure. Malondialdehyde, a marker of lipid peroxidation, reached its highest levels after 30 and 90 minutes compared to controls. The results indicate that platelets are sensitive to this environmental factor.
Tkalec M, Malaric K, Pevalek-Kozlina B. · 2005
Researchers evaluated duckweed growth and peroxidase activity after exposure in a Gigahertz Transversal Electromagnetic (GTEM) cell to electric fields at frequencies of 400, 900, and 1900 MHz. Plants exposed for 2 h to a 23 V/m field at 900 MHz showed significantly decreased growth compared with the control, while the same field strength at 400 MHz did not have such an effect. Peroxidase activity in exposed plants varied depending on exposure characteristics, with a significant increase of 41% found in plants exposed for 2 h to 41 V/m at 900 MHz.
Yokus B, Cakir DU, Akdag MZ, Sert C, Mete N · 2005
Researchers examined the effects of extremely low frequency electromagnetic fields (50 Hz, 0.97 mT) on oxidative DNA damage and lipid peroxidation in rats. Measurements of 8OHdG and TBARS were taken at 50 and 100 days to look for time-dependent changes. The 8OHdG levels of the exposed group were significantly higher than the sham group at both 50 and 100 days (p<0.001). The extent of DNA damage and lipid peroxidation appeared to depend on exposure time.
Wolf FI et al. · 2005
Researchers exposed HL-60 leukemia cells, Rat-1 fibroblasts, and WI-38 diploid fibroblasts to 0.5–1.0-mT 50-Hz extremely low frequency electromagnetic fields for 24–72 hours. The treatment produced a dose-dependent increase in cell proliferation, with about a 30% increase after 72 hours of exposure to 1.0 mT. A dose-dependent increase in DNA damage was observed in all cell lines, with two peaks occurring at 24 and 72 hours. Both effects were prevented by pretreatment with α-tocopherol, suggesting that redox reactions were involved.
Hook, G. · 2004
The study measured intracellular oxidants, glutathione disulfide accumulation, antioxidant enzyme activities, nitric oxide production, and cell viability. FMCW- and CDMA-modulated RF radiation did not alter any measured oxidative stress parameters or cell toxicity.
Unknown authors · 2004
The authors review studies documenting melatonin's influence on the activity and expression of glutathione peroxidase, superoxide dismutases, and catalase. Melatonin has been shown to possess genomic actions that regulate the expression of several genes. Melatonin also influences both antioxidant enzyme activity and cellular mRNA levels for these enzymes. The review also analyzes possible mechanisms by which melatonin regulates these enzymes.
Ramundo-Orlando A, Liberti M, Mossa G, D'Inzeo G. · 2004
Enzyme activity decreased only at 5.6 W/kg, with no response at lower SAR values. When using deglycated ascorbate oxidase without oligosaccharide chains, microwave irradiation caused no enzyme activity changes, indicating the chains are necessary for the effect. Catalytic properties of both enzyme forms were unaffected by microwave exposure in solution or in liposomes, ruling out enzyme conformational changes as a mechanism. The authors concluded that oligosaccharide chains of ascorbate oxidase are critical for microwave effects on lipid membranes.
Hook et al. · 2004
Researchers exposed J774.16 mouse macrophage cells to FMCW radiation at 835.62 MHz and CDMA radiation at 847.74 MHz for 20–22 hours at a specific absorption rate of 0.8 W/kg. Cells were stimulated with γ-interferon and bacterial lipopolysaccharide before exposure. The results indicated that FMCW- and CDMA-modulated RF radiation did not alter parameters indicative of oxidative stress in J774.16 cells.
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.
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.
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.
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.
Zwirska-Korczala K et al. · 2004
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.
Ozguner F, Aydin G, Mollaoglu H, Gokalp O, Koyu A, Cesur G. · 2004
Researchers used thirty male Wistar-Albino rats divided into a nontreated control group, an irradiated group, and an irradiated group that also received melatonin. The irradiated group received 900 MHz radiation for 10 days at 30 minutes per day, and skin grafts were taken from the thoraco-abdominal area at the end of the tenth day. In the irradiated group, researchers observed increased thickness of stratum corneum, atrophy of epidermis, papillamatosis, basal cell proliferation, hypergranulosis, capillary proliferation, and impairment in collagen tissue distribution compared to the control group. Most of these changes, except hypergranulosis, were prevented with melatonin treatment.
Zmyślony M et al. · 2004
