Assessing the effect of selenium on cyclin D1 level and nuclear factor kappa b activity in NIH/3T3 fibroblast cells at 2100 MHz electromagnetic field exposure.

Although there are numerous studies on the health impacts of electromagnetic field (EMF) of mobile phone operation frequency 2100 MHz, the published works present contradicting results. Long-term exposure to mobile phone frequencies has unclear health hazards. Therefore, it is important to investigate the molecular mechanism of possible biological effects in mobile phone exposure and to determine the corresponding biological markers. Towards this end, this study was designed to assess the effect of 200 nM selenium (Se) on cell viability% [trypan blue], cell cycle biomarker [cyclin D1] and the transcription factor [nuclear factor kappa b (NF-κB)] in NIH/3T3 fibroblast cells when exposed to 2100 MHz mobile phone frequency. When 2100 MHz EMF was exposed to NIH/3T3 fibroblast cells, the cell viability% was reduced, whereas cyclin D1 level and NF-kB activity increased. Also we show that Se supplementation decreases the effects of 2100 MHz EMF on these parameters. Although future studies will be required to investigate the biological effects of EMF emitted by mobile phones, the results obtained here provide an insight into the molecular mechanisms and specifically underlying selenium's protective effect against 2100 MHz EMF exposure.

Investigation of extracellular medium osmolality depending on zinc application and incubation time on A549 cancer cells.

Changes in the osmolality of the extracellular medium (ECM) affect cell volume and cellular processes such as cell migration and proliferation. Not only may high concentrations of zinc (Zn) lead to cell death by apoptosis, but Zn is also a physiological suppressor of apoptosis. The aim of our study was to examine whether Zn and regulation of extracellular osmolality had an effect on the lung cancer cell line (A549) and how to be changed in ECM according to elements and osmolality depending on incubation time and Zn application. Our study consisted of four groups: cell-free medium, ECM of cancer cell after 24 h incubation (24hECM), ECM of cancer cell after 48 h incubation (48hECM), and ECM of cancer cell after 48 h incubation with ZnCl2 (48hECM + Zn). ECM osmolality was measured by using osmometer, and the levels of chromium (Cr), iron (Fe), and magnesium (Mg) elements were analyzed using ICP-OES device for all groups. According to the result of the analysis, a statistically significant difference was found when osmolality and element values of ECM of 24hECM and 48hECM groups were compared with the values of the 48hECM + Zn group. It was observed that there was a decrease in the levels of Cr, Fe, and Mg with Zn application and incubation period in ECM. The regulation of ECM osmolality is a promising method due to biophysical effects on cancer cells. In our study, we speculated that the understanding of the effects of Zn and osmolality with the relationship between ECM and cancer cell might lead to the discovery of biophysical approaches as a novel therapeutic strategy.

Investigation of Aryl Hydrocarbon Receptor, Zinc, and Vitamin B12 Levels in Chronic Gastritis with Helicobacter pylori Infection.

Helicobacter pylori (H. pylori) infection is known as the most common cause of worldwide common chronic gastritis. Pathogenic mechanisms caused by H. pylori in diseases are still not fully understood. In addition, it has been reported that H. pylori can alter gene expressions in infected tissues and affect transcription factor activation. It is reported that aryl hydrocarbon receptor (AhR), which is a cytoplasmic transcription factor, functions in the immune system and plays a role in immune cells in barrier organs such as the gastrointestinal system, skin, and lungs. H. pylori infection affects the absorption of micronutrients such as trace elements, minerals, and vitamins by disrupting gastric secretion and acidification functions. Zinc (Zn) trace element is thought to be able to modulate the induction of AhR-responsive genes in endothelial cells. Although it is emphasized that trace elements are related with gastritis, relationship between Zn and AhR is not fully known, especially in chronic gastritis accompanied by H. pylori infection. In this study, serum levels of AhR, Zn, and AhR antagonist vitamin B12 were determined in chronic gastritis with H. pylori infection. Fifty volunteers diagnosed with H. pylori positive and negative chronic gastritis were included in this study. Collected from individuals participating were 5 ml of venous blood samples, and their serums were separated. AhR serum level of the study group was determined using enzyme-linked immunosorbent assay method. Zn concentrations in serum samples were measured using inductively coupled plasma atomic emission spectroscopy. When AhR and Zn serum levels were compared in H. pylori positive and negative chronic gastritis patients, it was found that AhR serum level of H. pylori positive chronic gastritis patients increased but it was not statistically significant (p = 0.595). However it was determined Zn and B12 serum levels were statistically significantly decreased (p < 0.001). This study has a crucial importance since to be the first one investigating relationship between serum AhR, Zn, and vitamin B12 levels in the pathogenesis of H. pylori gastritis in adults. Examination of AhR, Zn and B12 levels in H. pylori positive gastritis patients contributes to elucidating molecular mechanism of the disease.

Protective Effects of Zinc on 2.45 GHz Electromagnetic Radiation-Induced Oxidative Stress and Apoptosis in HEK293 Cells.

Several epidemiological studies have shown that exposure to electromagnetic radiation (EMR) can be harmful to human health. The purpose of this study was to examine oxidative parameters and apoptosis induced by EMR in human kidney embryonic cells (HEK293) and to investigate whether zinc (Zn) has protective effect on EMR-induced apoptosis in HEK293 cells. For our experiment, HEK293 cells were divided into four main groups, control, EMR, 50 µM Zn + EMR, and 100 µM Zn + EMR. HEK293 cells of EMR groups were exposed to 2.45 GHz EMR for 1 h. In Zn groups, HEK293 cells were incubated with different concentrations of Zn for 48 h before EMR exposure. Oxidative stress parameters were determined by spectrophotometric method; bcl-2 and caspase-3 were assessed immunohistochemically and TUNEL method was performed for apoptotic activity. EMR group had higher malondialdehyde (MDA) level and lower superoxide dismutase (SOD) activity compared with control group. In Zn-applied groups, MDA was decreased and SOD activity was increased compared with EMR group. The number of the apoptotic cells and caspase-3 immunopositive cells at EMR group was increased significantly compared with the control group, whereas bcl-2 was decreased. Besides, Zn-treated groups showed a significant reduction in the number of apoptotic cells and caspase-3 from that of EMR group, whereas there was an increase in bcl-2 immunopositivity. Our findings show that EMR caused oxidative stress and apoptotic activation in HEK293 cells. Zn seems to have protective effects on the EMR by increasing SOD activity and bcl-2 immunopositivity, decreasing lipid peroxidation and caspas-3 immunopositivity.

Effects of Quercetin on Lipid and Protein Damage in the Liver of Streptozotocin-Induced Experimental Diabetic Rats.

Quercetin (QR) is part of a subclass of flavonoids called flavonols. We aimed to investigate the effect of QR on malondialdehyde (MDA), advanced oxidation protein products (AOPPs), and glutathione peroxidase (GSH-Px) activity in the liver of diabetic rats. We compared four groups of male adult Wistar albino rats: a control group, an untreated diabetic group, diabetic groups treated with QR, and QR group. Diabetes was induced by a single injection of streptozotocin (STZ) (50 mg/kg). Animals were kept in standard condition. On the 31st day of the study, the liver tissue was removed for biochemical parameters and histopathological evaluations. In an untreated diabetic group, liver MDA and AOPP levels were significantly higher than all groups. QR treatment significantly decreased the increased MDA, AOPP levels, and increased the decreased GSH-Px enzyme activity in liver tissues. The QR-treated rats in the diabetic group showed an improved histological appearance. Lesser vesicular vacuolization and fibrotic areas were observed in the QR-treated diabetic group than in the diabetic group. The STZ-induced liver injury is associated with oxidative stress, and coadministration of QR may reduce this damage effectively in a rat model. Our results are also supported by morphological improvement in liver tissue. Therefore, we think QR may be effective in treating hyperglycemia and oxidative damage in diabetes.