Ewa Kurzeja

Effect of a Static Magnetic Fields and Fluoride Ions on the Antioxidant Defense System of Mice Fibroblasts

The results of studies on the biological influence of magnetic fields are controversial and do not provide clear answers regarding their impact on cell functioning. Fluoride compounds are substances that influence free radical processes, which occur when the reactive forms of oxygen are present. It is not known whether static magnetic fields (SMF) cause any changes in fluoride assimilation or activity. Therefore, the aim of this work was to determine the potential relationship between magnetic field exposure to, and the antioxidant system of, fibroblasts cultured with fluoride ions. Three chambers with static magnetic fields of different intensities (0.4, 0.6, and 0.7 T) were used in this work. Fluoride ions were added at a concentration of 0.12 mM, which did not cause the precipitation of calcium or magnesium. The results of this study show that static magnetic fields reduce the oxidative stress caused by fluoride ions and normalize the activities of antioxidant enzymes, including superoxide dismutase (SOD), glutathione peroxidase (GPx), and catalase (CAT). Static magnetic fields modify the energy state of fibroblasts, causing an increase in the ATP concentration and a decrease in the MDA concentration. These results suggest that exposure to fluoride and an SMF improves the tolerance of cells to the oxidative stress induced by fluoride ions.

Studies on the effect of quercetin and nitrates on the redox homeostasis using in vitro model.

Antioxidants are widely considered to be a preventive measure for many diseases and beneficial for health. However, an increasing number of reports suggest a lack of any influence by antioxidants on health or even harmful pro-oxidative effects of antioxidants. In most cases, the research was conducted with respect to a chosen antioxidant, without considering the presence of other chemical substances present in food, with which these compounds may react. The aim of this work was to determine whether and to what extent the simultaneous presence of quercetin and sodium nitrate influences oxidative-reductive homeostasis in fibroblast cultures. Superoxide dismutase (SOD), glutathione peroxidase (GPx), glutathione reductase (GR), and nitric oxide synthase (NOS) activities were measured together with nitric oxide (NO) concentration and total antioxidant status (TAS). An increase in the activity of all the enzymes measured and in the NO concentration was determined compared with the control culture. The most prominent changes were observed at the highest quercetin concentration. These results indicate that the simultaneous presence of quercetin and sodium nitrate disrupts the oxidative-reductive homeostasis in fibroblasts.

Influence of static magnetic fields up to 700 mT and dihydrochalcones on the antioxidant response in fibroblasts

ABSTRACT The effects of a static magnetic field (SMF) and the dihydrochalcones phloretin and phloridzin on the redox homeostasis of fibroblasts were investigated. The aim of the present study was to determine the redox homeostasis of fibroblasts that were simultaneously exposed to a static magnetic field and the dihydrochalcones phloretin and phloridzin. The fibroblasts were cultured for 72 h in special magnetic test chambers at different moderate intensities (0.4, 0.55 and 0.7 T). In this report, the activities of superoxide dismutase (SOD), glutathione peroxidase (GPx), catalase (CAT), glutathione transferase (GST); the concentrations of malondialdehyde (MDA), adenosine triphosphate (ATP) and total antioxidant status were measured using commercially available kits. We did not observe any impairment in the redox balance in cells in fibroblasts that were only exposed to static magnetic fields of different intensities or In fibroblast cultured with dihydrochalcones and exposed to static magnetic field increase the SOD, GPx, GST activities and MDA concentration. Our investigations revealed that the activities of SOD, GPx, GST and the concentration of MDA that were determined for the fibroblasts that were cultured with dihydrochalcones were higher in the presence of a static magnetic field. Our results indicated that exposure to SMF (0.7 T) with dihydrochalcones induces oxidative stress in fibroblasts.

Cathepsin D activity in nasal polyps.

OBJECTIVES The aim of the study was to assess the activity of cathepsin D in polyps removed during first-time FESS surgery and in recurrent polyps removed during successive FESS surgeries. DESIGN AND METHODS The study examined 24 polyps: 11 polyps were removed during first-time surgical procedures (termed primary polyps in the study), and 13 recurrent polyps were removed in successive FESS surgeries (termed polyps after re-polypectomy in the study). The activity of cathepsin D was determined by measuring the tyrosine released from denatured hemoglobin. RESULT The average cathepsin D activity in polyps after re-polypectomy was 74% higher than the average activity in primary polyps, whereas the difference between the maximum and the minimum cathepsin D activities in polyps after re-polypectomy was twofold greater than the respective difference in primary polyps. CONCLUSION Differences in cathepsin activity and the protein content, likely to be significant in the process of polyp recurrence, were observed in both groups of polyps.