Review of in vivo static and ELF electric fields studies performed at Gazi Biophysics Department

The protective role of 5-hydroxy-1,4-naphthoquinone against the harmful effects of 50 Hz electric field in rat lung tissue

There is strong scientific evidence that the electric field is harmful to life. Exposure to an electric field (EF) can cause lung toxicity and respiratory disorders. In addition, the electric field has been shown to cause tissue damage through inflammation and apoptosis. Juglone (JUG) is one of the powerful antioxidants with anti-apoptotic and anti-inflammatory, various pharmacological properties in the biological system. In this study, we evaluated the efficacy of JUG against the potential adverse effects of electric field on the lung. Twenty-four Wistar albino rats were randomly divided into three groups; control group (Cont), EF group, and EF exposure+JUG-treated group (EJUG). After routine histological procedures, sections stained with hematoxylin-eosin (H&E) showed significant changes in lung tissues in the EF group compared to the Cont group. Significant protective effects were observed in the building volumes and histopathology in the EJUG group. Our immunohistochemical and gene expression results increased the expression of caspase-3 and tumor necrosis factor alpha (TNF-α) in the EF group (p < 0.05). Juglon increased cytokine signal suppressor (SOCS) expression (p < 0.001). These findings were consistent with the antioxidant effect of JUG treatment. We reasoned that exposure to EF damaged rat lung tissues and administration of JUG alleviated the complications caused by 50 Hz EF.

Effects of RF and ELF Radiation on Oxidative Stress of Brain Tissue and Plasma of Diabetic Rats

Objective: Exposure to Radio Frequency (RF) and Extremely Low Frequency (ELF) radiation is increasing steadily with the progress of technology and industrialization. The aim of this study was to investigate whether RF and ELF radiation are oxidative stress effects in the plasma and brain tissue of diabetic and non-diabetic rats. Methods: Experiment groups were designed as follows; C (control), S (sham), ELF (ELF radiation exposure), RF (RF radiation exposure), ELF+RF (ELF and RF radiation exposure), D-C (Diabetic Control), D-S (Diabetic Sham), D-ELF (Diabetic ELF), D-RF (Diabetic RF), D-ELF+RF (Diabetic ELF+RF). The experimental diabetes model was induced with a single dose of 65mg/kg streptozotocin (STZ). 2100 MHz RF and 50 Hz ELF radiation groups exposed for 1 month. Total nitric oxide (NOx), malondialdehyde (MDA) and total sulfhydryl groups (RSH) / glutathione (GSH) levels were measured in plasma and brain tissue. Results: RF + ELF radiation exposure caused an increase in NOx and MDA levels in plasma and brain tissue of diabetic and non-diabetic rats (p&lt;0.05). Exposure to RF and RF + ELF radiation caused a decrease in plasma RSH / tissue GSH levels in non-diabetic rats (p&lt;0.05). Conclusion: The most prominent effect was seen in the diabetic group with RF + ELF radiation exposure.

Testosterone synthesis in testicular Leydig cells after long-term exposure to a static electric field (SEF)

China's clean energy and resources are mainly located in the west and north while electric load center is concentrated in the middle and east. Thus, these resources and energy need to be converted into electrical energy in situ and transported to electric load center through ultra-high voltage direct current (UHVDC) transmissions. China has built 25,000 km UHVDC transmission lines of 800 kV and 1100 kV, near which the impact of electric field on health has attracted public attention. Previous studies showed that time-varying electromagnetic field exposure could disturb testosterone secretion. To study the effect of non-time-varying electric field caused by direct current transmission lines on testosterone synthesis, male ICR mice were continually (24 h/d) exposed to static electric field of 56.3 ± 1.4 kV/m. Results showed that on the 3^rd day of exposure and on the 7^th day after ceasing the exposure of 28 d, serum testosterone level and testicular oxidative stress indicators didn't change significantly. On the 28^th day of exposure, serum testosterone levels, testicular glutathione peroxidase (GSH-Px) activity, the mRNA and protein levels of testicular StAR, PBR, CYP11A1 decreased significantly, and testicular malondialdehyde (MDA) content increased significantly. Meanwhile, electron-dense edges and vacuolation appeared in lipid droplets of Leydig cells. The gap between inner mitochondrial membrane (IMM) and outer mitochondrial membrane (OMM) enlarged, which would cause the swelling of mitochondria, the rupture and deficiency of mitochondrial membranes. Analysis showed that testicular oxidative stress could induce the damage of mitochondrial structure in Leydig cells, which would decrease the rate of cholesterol transport from cytoplasm to mitochondria. Since cholesterol is the necessary precursor of testosterone synthesis, testosterone synthesis was inhibited. The decrease of the mRNA and protein expression levels of StAR and PBR in testes could diminish the cholesterol transported from OMM to IMM. The decrease of the mRNA and protein expression levels of CYP11A1 could reduce the pregnenolone required in testosterone synthesis and inhibit testosterone synthesis consequently.

Altered morphology and biochemistry of the female rat liver following 900 megahertz electromagnetic field exposure during mid to late adolescence

Despite their benefits, technological devices such as cell phones may also have deleterious effects on human health. Considerable debate continues concerning the effects of the electromagnetic field (EMF) emitted during cell phone use on human health. We investigated the effects of exposure to 900 megahertz (MHz) EMF during mid to late adolescence on the rat liver. Control (ContGr), sham (ShmGr) and EMF (EMFGr) groups of female rats were established. We exposed the EMFGr rats daily to 900 MHz EMF on postnatal days 35-59. ShmGr rats underwent sham procedures. No procedure was performed on ContGr rats. Rats were sacrificed on postnatal day 60 and the livers were extracted. One part of the liver was stained with Masson's trichrome or hematoxylin and eosin. The remaining tissue was used to measure oxidative stress markers including malondialdehyde, glutathione, catalase, superoxide dismutase, 8-hydroxydeoxyguanosine (8-OHdG) and nitrotyrosine. Total antioxidant status and total oxidant status were used to calculate the oxidative stress index. We found normal hepatic morphology in the ContGr and ShmGr groups. The EMFGr group exhibited occasional irregularities in the radial arrangement of hepatocytes, cytoplasmic vacuolization, hemorrhage, sinusoid expansion, hepatocyte morphology and edema. Biochemical analysis revealed that 8-OHdG and SOD levels in EMFGr decreased significantly compared to the ContGr and ShmGr groups. Exposure to a continuous 900 MHz EMF for 1 h daily during mid to late adolescence may cause histopathological and biochemical alterations in hepatic tissue.

Radiations and male fertility

During recent years, an increasing percentage of male infertility has to be attributed to an array of environmental, health and lifestyle factors. Male infertility is likely to be affected by the intense exposure to heat and extreme exposure to pesticides, radiations, radioactivity and other hazardous substances. We are surrounded by several types of ionizing and non-ionizing radiations and both have recognized causative effects on spermatogenesis. Since it is impossible to cover all types of radiation sources and their biological effects under a single title, this review is focusing on radiation deriving from cell phones, laptops, Wi-Fi and microwave ovens, as these are the most common sources of non-ionizing radiations, which may contribute to the cause of infertility by exploring the effect of exposure to radiofrequency radiations on the male fertility pattern. From currently available studies it is clear that radiofrequency electromagnetic fields (RF-EMF) have deleterious effects on sperm parameters (like sperm count, morphology, motility), affects the role of kinases in cellular metabolism and the endocrine system, and produces genotoxicity, genomic instability and oxidative stress. This is followed with protective measures for these radiations and future recommendations. The study concludes that the RF-EMF may induce oxidative stress with an increased level of reactive oxygen species, which may lead to infertility. This has been concluded based on available evidences from in vitro and in vivo studies suggesting that RF-EMF exposure negatively affects sperm quality.

Effects of 900-MHz electromagnetic fields exposure throughout middle/late adolescence on the kidney morphology and biochemistry of the female rat

The effect of the electromagnetic field (EMF) established when cell phones are in use on human health, and particularly the head, has been the subject of major scientific research. Phones are usually carried near the lumbar region when not in use, and the kidneys will also inevitably be affected by such fields. We investigated the effects on the kidneys of female rats exposed to a continuous 900-megahertz (MHz) EMF for 1 h daily in mid-late adolescence. Control, sham, and EMF groups were established. The EMF was applied to the application group rats daily on postnatal days 35-59. A pseudo-megahertz effect was applied to sham group rats. All animals were euthanized on postnatal day 60. Right kidney tissues were subjected to routine procedures. Malondialdehyde, total antioxidant status, and total oxidant status (TOS) were investigated in left kidneys, and the oxidative stress index (OSI) was also calculated from these. Histopathological analysis revealed no pathology in either the control or sham groups. However, findings including hemorrhage in glomerulus, vacuolization and irregularity in the proximal and distal tubular epithelium, diffuse glomerular degeneration and edema, occasional degeneration in Bowman capsules, hemorrhage in the medullary region, disturbed nucleus location and morphology, and tubular edema in the cortex were observed in the EMF groups. TOS and OSI values were lower in the EMF group (9.4316 ± 1.0211 and 0.8461 ± 0.0826, respectively) and the sham group (8.2171 ± 0.6437 and 0.7358 ± 0.0545, respectively) than in the control group (11.1522 ± 1.3389 and 1.0085 ± 0.1174, respectively) ( p < 0.05). In conclusion, exposure to a continuous 900-MHz EMF for 1 h daily during middle and late adolescence may cause various changes in the female rat kidney at postnatal day 60.

Effect of in vivo and in vitro exposure to electrostatic field on some hematological parameters in rats

The aim of this study was to investigate the effect of the external electrostatic field (ESF) on some hematological parameters in rats. Both in vivo and in vitro experiments were carried out. In in vivo investigations, rats were exposed to ESF (200 kV/m) during short (1 h) and long periods (6 days, 6 h daily). For in vitro study, the blood of intact rats was exposed to ESF for 1 h. Blood hematology was measured using validated ABX Micros ESV 60 Veterinary Hematology Analyzer. DNA damage in blood leucocytes was detected by means of comet assay. ESF effect on blood cell count was mainly manifested in white blood cells (WBC) and platelets. Damage of WBC was shown both in vitro and in vivo despite alterations in the count. This means the observed increase in WBC count in some cases might be a result of WBC compensatory mobilization from the bone marrow. Red blood cell (RBC) count and related parameters were slightly affected by ESF. Nevertheless, alterations in the shape and size of RBC were manifested. All ESF effects were extinguished in 14 days after the end of exposure. Bioelectromagnetics. 37:513-526, 2016. © 2016 Wiley Periodicals, Inc.

Biological effects of the electrostatic field: red blood cell-related alterations of oxidative processes in blood

The aim of this study was to determine activities of pro-/antioxidant enzymes, reactive oxygen species (ROS) content, and oxidative modification of proteins and lipids in red blood cells (RBCs) and blood plasma of rats exposed to electrostatic field (200 kV/m) during the short (1 h) and the long periods (6 day, 6 h daily). Short-term exposure was characterized by the increase of oxidatively damaged proteins in blood of rats. This was strongly expressed in RBC membranes. After long-term action, RBC content in peripheral blood was higher than in control (P < 0.01) and the attenuation of prooxidant processes was shown.

HIGHLIGHTS

External electrostatic field (200 kV/m) alters the balance in pro-/antioxidant processes. We examine oxidative processes in plasma and RBC (hemolysate and membranes). Biological effects of static electric field depend on exposure time. Acute action of electrostatic field (ESF) characterized by activation of the prooxidant processes. Long-term exposure reflected with prevalence of antioxidant activities.

Effects of prenatal 900 MHz electromagnetic field exposures on the histology of rat kidney

PURPOSE

To research the harmful effects of prenatal exposure of 900 megahertz (MHz) electromagnetic field (EMF) on kidneys of four-week-old male rats and to determine protective effects of melatonin (MEL) and omega-3 (ω-3).

MATERIALS AND METHODS

Twenty-one Wistar albino rats were randomly placed into seven groups as follows: Control (Cont), Sham, MEL, ω-3, EMF, EMF+ MEL and EMF+ω-3. After mating, three groups (EMF, EMF+ MEL, EMF+ ω-3) were exposed to an EMF. In the fourth week subsequent to parturition, six rats were randomly chosen from each group. Mean volume of kidneys and renal cortices, the total number of glomeruli and basic histological structure of kidney were evaluated by stereological and light microscopical methods, respectively.

RESULTS

Stereological results determined the mean volume of the kidneys and cortices were significantly increased in EMF-exposed groups compared to the Cont group. However, EMF-unexposed groups were not significantly modified compared to the Cont group. Additionally, the total number of glomeruli was significantly higher in EMF-unexposed groups compared to the Cont group. Alternatively, the number of glomeruli in EMF-exposed groups was decreased compared to the Cont group.

CONCLUSIONS

Prenatal exposure of rat kidneys to 900 MHz EMF resulted in increased total kidney volume and decreased the numbers of glomeruli. Moreover, MEL and ω-3 prevented adverse effects of EMF on the kidneys.

The developmental effects of extremely low frequency electric fields on visual and somatosensory evoked potentials in adult rats

The purpose of our study was to investigate the developmental effects of extremely low frequency electric fields (ELF-EFs) on visual evoked potentials (VEPs) and somatosensory-evoked potentials (SEPs) and to examine the relationship between lipid peroxidation and changes of these potentials. In this context, thiobarbituric acid reactive substances (TBARS) levels were determined as an indicator of lipid peroxidation. Wistar albino female rats were divided into four groups; Control (C), gestational (prenatal) exposure (Pr), gestational+ postnatal exposure (PP) and postnatal exposure (Po) groups. Pregnant rats of Pr and PP groups were exposed to 50 Hz electric field (EF) (12 kV/m; 1 h/day), while those of C and Po groups were placed in an inactive system during pregnancy. Following parturition, rats of PP and Po groups were exposed to ELF-EFs whereas rats of C and Pr groups were kept under the same experimental conditions without being exposed to any EF during 68 days. On postnatal day 90, rats were prepared for VEP and SEP recordings. The latencies of VEP components in all experimental groups were significantly prolonged versus C group. For SEPs, all components of PP group, P2, N2 components of Pr group and P1, P2, N2 components of Po group were delayed versus C group. As brain TBARS levels were significantly increased in Pr and Po groups, retina TBARS levels were significantly elevated in all experimental groups versus C group. In conclusion, alterations seen in evoked potentials, at least partly, could be explained by lipid peroxidation in the retina and brain.

Biological effects of static electric field: Plasma/serum proteome analysis of rats

The external static electric field (SEF) of man-made origin brings to the substantially increased SEF background in a human environment the biological activity of which is a moot question. The paper reports on rats blood plasma/serum proteome modifications by means of 1D polyacrilamide gel electrophoresis and clotting process alterations after the short- and long-term SEF exposures of 200 kV/m. The results indicate decrease of fast α1 and α2 globular proteins in plasma coinciding with clotting acceleration after the short-term SEF, and attenuation of clotting-dependent proteome modifications reflected with incomplete coagulation after the long-term SEF exposure. Increased lysozyme activity in serum unlike plasma was observed after both SEF exposures. Applied model of the high-voltage SEF environment indicates dependence of biological systems functioning on the external SEF.

Investigation of the effects of 50 Hz magnetic fields on platelet aggregation using a modified aggregometer

PURPOSE

Electromagnetic fields have various effects on intracellular calcium levels, free oxygen radicals and various enzymes. The platelet activation pathway involves an increase in intracellular calcium levels and protein kinase C activation; and free oxygen radicals play a mediating role in this pathway. This study investigated whether 1 mT and 6 mT, 50 Hz magnetic fields had any effects on platelet aggregation.

MATERIALS AND METHODS

Blood from healthy volunteers was anticoagulated with either citrate or heparin. Each sample was divided in half and assigned to exposure and control groups. Platelet rich plasma samples in the exposure group were exposed to a 1 mT or a 6 mT, 50 Hz magnetic field for 1.5 or 1 h, respectively. The samples from both exposure and control groups were simultaneously evaluated using a modified optical aggregometer. Adenosine-diphosphate, collagen, and epinephrine were used as inducing agents. The slopes of the aggregation curve, the maximum values and the areas under the curves were recorded and compared.

RESULTS

A significant effect was observed only in the 1 mT-citrate group. It was found that magnetic field exposure significantly increased the maximum values and slopes of the collagen-induced aggregations.

CONCLUSIONS

It was found that magnetic field exposure has an activating effect on platelet aggregation.

Electrical field stimulation promotes anastomotic healing in poorly perfused rat colon

INTRODUCTION

Hypoperfusion of the bowel is a risk factor for anastomotic failure. Electrical field stimulation has been shown to improve repair in ischemic tissue, but its influence in hypoperfused colon has not been investigated. The hypothesis of this experimental animal study was that electrical field stimulation improves anastomotic healing in ischemic bowel.

MATERIALS AND METHODS

Thirty rats were divided evenly into three groups: control, ischemia/placebo, and ischemia/test group. Ischemia was induced by ligation of the arterial supply to the proximal colon. The watershed area was identified and transected. Field stimulation was achieved by application of negatively charged diethylaminoethyl Sephadex beads in methylcellulose gel to the colonic epithelium prior to anastomosis. The placebo group had methylcellulose gel only applied and control animals had anastomosis only. Anastomotic strength was measured using anastomotic bursting pressure and hydroxyproline content. Systemic effect was investigated via interleukin-6 and vascular endothelial growth factor assay.

RESULTS

The ischemia/electrical field stimulation (EFS) group had significantly increased bursting pressure and hydroxyproline content in comparison with the placebo group (P < 0.001). Serum cytokine levels were unaffected.

CONCLUSION

Negatively charged EFS improves anastomotic healing in hypoperfused colon without induction of systemic cytokines and has potential as a local treatment in high-risk bowel anastomosis.

Effects of acute and chronic low frequency electromagnetic field exposure on PC12 cells during neuronal differentiation

BACKGROUND/AIMS

The purpose of this study was to provide information about the in vitro neuritogenesis during cell exposure to extremely low frequency electromagnetic fields (ELF-EMFs) of different intensities and durations using pheochromocytoma-derived cell line (PC12 cells) as neuronal model.

METHODS

Proliferative rates and neuritogenesis were tested by colorimetric assay and morphological analysis, respectively; reactive oxygen species (ROS) levels and intracellular Ca(2+) variations monitored using single cell videomicroscopy.

RESULTS

The long-lasting ELF-EMF exposure (0.1-1.0 mT) did not appear to significantly affect the biological response (proliferation and neuritogenesis). However, during the acute ELF-EMF exposure (30 min), in undifferentiated PC12 cells, there were increased ROS levels and decreased catalase activity, that, conversely, resulted increased after chronic exposure (7 days) at 1.0 mT. Acute exposure (0.1-1.0 mT) affected the spontaneous intracellular Ca(2+) variations in undifferentiated cells, in which basal intracellular Ca(2+) resulted increased after chronic exposure. In addition acute exposure affected cell response to a depolarizing agent, while basal membrane potential was not changed.

CONCLUSION

Even if further studies remain necessary to identify the ROS/intracellular Ca(2+)cross-talking pathway activated by ELF-EMF exposure, we support the hypothesis that ROS and Ca(2+) could be the cellular "primum movens" of the ELF-EMF induced effects on biological systems.