Electromagnetic Biology and Medicine最新文献

This study aims to determine whether exposure to non-ionizing radiofrequency fields could induce an adaptive response (AR) in adult mice and to reveal potential molecular mechanisms triggered by RF-induced AR. The study was performed on 24 adult male Swiss-Albino mice. The average mass of the mice was 37 g. Four groups of adult mice, each consisting of 6, were formed. The radiofrequency group (R) and the adaptive response group (RB) were exposed to 900 MHz of global system for mobile communications (GSM) signal at 0.339 W/kg (1 g average specific absorption rate) 4 h/day for 7 days, while the control group (C) and the bleomycin group (B) were not exposed. 20 minutes after the last radiofrequency field (RF) exposure, the mice in the B and RB groups were injected intraperitoneal (ip) bleomycin (BLM), 37.5 mg/kg. All the animals were sacrificed 30 minutes after the BLM injection. Oxidative damage and antioxidant mechanism were subsequently investigated in the blood samples. Changes in the expression of the genes involved in DNA repair were detected in the liver tissue. TUNEL method was used to determine the apoptosis developed by DNA fragmentation in the liver tissue. The RB group, which produced an adaptive response, was compared with the control group. According to the results, the increase of reactive oxygen species (ROS) in the RB group may have played an important role in triggering the adaptive response and producing the required minimum stress level. Furthermore, tumor suppressor 53(p53), oxo guanine DNA glycosylase (OGG-1) levels responsible for DNA repair mechanism genes expression were increased in conjunction with the increase in ROS. The change in the poly (ADP-ribose) polymerase 1 (PARP-1) and glutathione peroxidase 1 (GPx-1) gene expression were not statistically significant. The antioxidant enzyme levels of superoxide dismutase (SOD), catalase (CAT), and total antioxidant capacity (TAC) were decreased in the group with adaptive response. According to the data obtained from terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) analysis, apoptosis was decreased in the RB group due to the decrease in cell death, which might have resulted from an increase in gene expression responsible for DNA repair mechanisms. The results of our study show that exposure to RF radiation may create a protective reaction against the bleomycin. The minimal oxidative stress due to the RF exposure leads to an adaptive response in the genes that play a role in the DNA repair mechanism and enzymes, enabling the survival of the cell.

The presence of technological devices in our lives has increased exposure to environmental electromagnetic fields. As a result of this, especially Cancer and Diabetes are increasing.Rats were divided into 3 groups with 12 rats in each group. The 1st experimental group (n = 12) was exposed to a 50 Hz ELF magnetic field of 0.4 mT for 6 hours a day for 5 days, the 2nd experimental group (n = 12) was exposed for 10 days, and the control group (n = 12) was never exposed to a magnetic field. After completing the applications, blood collection from the rats was performed under appropriate conditions, measurements were made in the laboratory, and statistical analysis was performed between the groups. There was no significant difference between the groups in the results of transaminases and lipid profiles and C-Peptide. There was no significant difference in insulin, urea, creatinine, Na, K, Ca, and uric acid parameters between the groups. However, there was a significant increase in glucose, HbA1c, and Hba1 IFCC values between the control group and the experimental groups (p < .001). There was a significant increase in the level of Fetuin-A between the control group and the experimental groups (p < .05). There was an increase in the Fetuin-A, Glucose, HbA1c, and Hba1c IFCC values in both of the experimental groups compared to the control group. We believe that an increase in these values may cause Type 3 diabetes.

Radiofrequency radiation (RFR) as an environmental and physical pollutant may induce vulnerability to toxicity and disturb fetal development. Therefore, the potential health effects of short-term mobile phone like RFR exposure (GSM 1800 MHz; 14 V/m, 2 mW/kg specific absorption rate (SAR) during 15 min/day for a week) during pregnancy and also the development of fetuses were investigated. Hepatic glucose regulation and glutathione-dependent enzymes' capacities were biochemically analyzed in adult (female) and pregnant New Zealand White rabbits. Pregnant rabbits' two-day-old offspring were included to understand their developmental stages under short-term maternal RFR exposure. We analyzed two regulatory enzymes in the oxidative phase of phosphogluconate pathways to interpret the cytosolic NADPH's biosynthesis for maintaining mitochondrial energy metabolism. Moreover, the efficiencies of maternal glutathione-dependent enzymes on both the removal of metabolic disturbances during pregnancy and fetus development were examined. Whole-body RFR exposures were applied to pregnant animals from the 15th to the 22nd day of their gestations, i.e., the maturation periods of tissues and organs for rabbit fetuses. There were significant differences in hepatic glucose regulation and GSH-dependent enzymes' capacities with pregnancy and short-term RFR exposure. Consequently, we observed that intrauterine exposure to RFR might lead to cellular ROS- dependent disturbances in metabolic activity and any deficiency in the intracellular antioxidant (ROS-scavenging) system. This study might be a novel insight into further studies on the possible effects of short-term RF exposure and prenatal development.

The effects of thermotherapy on autonomic nervous system activity and subjective sensations of fatigue and arousal are unclear. This study compared the effects of capacitive and resistive electric transfer (Cret) interventions (deep thermotherapy) and hot packs (superficial thermotherapy) on autonomic nervous system activity in healthy young women (n = 16). Heart rate and RR interval were measured using electrocardiography, and the coefficient of variation (CV) of the RR interval was used to evaluate autonomic nervous system activity. The subjective relaxation effect was evaluated using the Roken Arousal Scale (RAS) - a fatigue arousal index. The intervention was performed on the lumbar region for 20 minutes for both Cret and hot pack. After each intervention, the CV values increased only in the Cret condition, whereas the heart rate decreased in both conditions. This suggests that parasympathetic activity was enhanced in the Cret condition. In contrast, the subjective relaxation evaluation observed a psychological relaxation effect under both conditions. Our results suggest that Cret application in the lumbar region has greater relaxation effects than hot pack application in the same region.

Previous studies reported that combined effect of magnetic field (MF) on cytotoxic drugs in human cancer cells. We focused on the effects of 60 Hz MF on drug activity in human uterine sarcoma MES-SA and drug-resistant variant MES-SA/Dx5 cells that overexpressed the membrane protein MDR1(P-glycoprotein), a drug efflux transporter for doxorubicin, daunorubicin, and etoposide, but not cisplatin. The cisplatin with MF caused 60% decrease in cell viability when compared with no MF treatment, cisplatin alone in MES-SA cells. Even in MES-SA/Dx5 cells, MF exposure equally enhanced cisplatin activity. Then, MF enhanced doxorubicin and daunorubicin activity in MES-SA cells and caused 60% decrease in the cell viability compared with these drugs only but had less effect on these drugs in MES-SA/Dx5 cells. Etoposide activity was unaffected by MF exposure in both cell lines, although etoposide is a MDR1 substrate as with doxorubicin and daunorubicin. Thus, MF had no direct impact on MDR1 in the cell membrane. However, the differences in doxorubicin and daunorubicin activity between MES-SA and MES-SA/Dx5 data revealed that the presence of MDR1 in abundance prevented the enhancing effects of MF on doxorubicin and daunorubicin activity. These results suggested that MF may act in the opposite direction of MDR1, affect the drug influx transporters for doxorubicin and daunorubicin, and facilitate anticancer drug uptake into the cells.

In this study, it is aimed to investigate the effect of radiofrequency radiation (RFR) on apoptotic and antiapoptotic factors under different exposure conditions in human colonic adenocarcinoma cells (Caco-2). We analyzed the effects of 2.5 GHz continuous wave and 3 GPP modulated radiofrequency radiation exposure (15 min on, 15 min off) for 1 h and (1 h on, 1 h off) for 3 hours on Caco-2 cell lines. The cell viability of Caco-2 cells was determined by XTT method. Then, the cells were analyzed by flow cytometry to determine the effects on apoptosis staining with AnnexinV-FITC and PI. Protein expression levels of Bcl-2, Bax, Caspase-3 and Survivin were subsequently analyzed by using flow cytometric methods. Bax, Caspase 8, and Survivin protein levels were also analyzed by western blot. The cell viability rates were not significantly different after 2.5 GHz of RFR exposure for 1 h, but RFR exposure for 3 h at 2.5 GHz frequencies caused a decrease on cell viability of Caco-2 cells. RFR exposure for 1 and 3 hours at 2.5 GHz frequencies resulted in an apoptotic response. Protein analyses of Bcl-2, Bax, Survivin, Caspase-3, and Caspase-8 showed that RFR led to increase the levels of proapoptotic Bax, Caspase-3, and Caspase 8 in Caco-2 cells under different exposure conditions. However, 3-h exposure caused a decrease in antiapoptotic survivin levels. The results of our study indicate that RFR exposure affects the cell death mechanism due to apoptotic pathway.

The present study aimed to assess the effect of the rTMS (repetitive Transcranial Magnetic Stimulation) intensity on the permeability of the BBB for brain-targeted drug delivery. For this purpose, different rTMS intensities including 70%, 100%, and 130% of Resting Motor Threshold (RMT) assessed in three groups of rats (three groups of 5 rats). Stimulation applied over the right hemisphere of the animals. The first phase of the study was composed of intravenous administration of Evans Blue Dye (EBD), rTMS stimulation and EBD uptake measurement in both brain hemispheres. The second examination was included rTMS stimulation, injection of the MRI Contrast Agent (CA), and signal intensity measurement in post-contrast images. Each exam also included five rats in a sham group. Thus, the total of 40 male Wistar rats enrolled in this study. There was no significant difference in the amount of EBD accumulated between the right hemisphere of the brain in the sham group and the group with 70% RMT magnetic stimulation, while this figure was significantly higher than the sham group for both 100 and 130% RMT groups. There was also a significant difference in this index between 100 and 130% groups. All of the results from the first phase of the study were consistent with the second assessment representing an upward trend of induced permeability by rising rTMS intensity. The results of this study imply that to cause an effective temporary disruption in the BBB the intensity of 100% RMT or above should be used for stimulation.