Lipid imbalance in individuals predisposed to rheumatoid arthritis: possible relationship with common infections.

Lipid balance was studied in female patients with late rheumatoid arthritis, their healthy female relatives liable to autoimmune diseases, and healthy women without family history of autoimmune diseases. Previous studies showed that the relatives of patients with rheumatoid arthritis suffered from frequent stubborn common infections, which prompted us to analyze the relationship between lipid metabolism and the infectious syndrome parameters. Blood serum and cells were collected for analysis when females had no clinical symptoms of infections (in all groups) or laboratory signs of inflammatory process (in the relatives and controls). Proatherogenic shifts in serum lipid composition presumably associated with frequent lasting infections were detected in individuals liable to rheumatoid arthritis development. Elevated cholesterol content in mononuclear leukocytes in this group could lead, in turn, to dysfunctions of these cells and augment the defects of anti-infection defense. The parameters of lipid balance in patients with late rheumatoid arthritis were close to the age-specific norm.

[The methods of analysis of DNA methylation].

The article deals with the review of methods of analysis of DNA methylation as one of key mechanisms of regulation of gene expression. The sites of aberrant methylation are potential markers of neoplastic transformation. At the present time, the development of clinical tests is in the process on basis of analysis of methylation to make prognosis and to diagnose oncologic diseases, micro metastases detection and prenatal diagnostics of certain hereditary syndromes. The comparative analysis of methods applied in clinical practice and in carrying out fundamental studies was made.

[Possible mechanisms of antioxidant activity of glycyrrhizic acid].

Possible mechanisms of antioxidant activity of glycyrrhizinic acid (GA) were studied. GA did not exhibit antiradical properties at the range of concentrations 1-100 mM as was shown in the experiments with stable radical 1,1-Diphenyl-2-picrylhydrazyl. These data were conformed by the study of GA influence on chemiluminescence of luminol in cell-free system with hydrogen peroxide. However, GA decreased generation of reactive oxygen species by PMA-FMLF-activated neutrophils. Addition of GA did not ifluence free radical level in neurons, however, cell preincubation with GA resulted in the decrease of free radicals production and the increase of intracellular glutathione level.

[Effect of perfluorocarbon emulsions on function of enzyme systems responsible for generating active forms of oxygen in neutrophils]. / Vliianie émul'sii perftoruglerodov na funktsionirovanie fermentnykh sistem, otvetstvennykh za generatsiiu aktivnykh form kisloroda v neitrofilakh.

The ability of the emulsion of perfluoroorganic compounds stabilized with proxanol 268 to affect the functions of peritoneal neutrophils was evaluated. The functional activity of neutrophils was estimated from the intensity of generation of reactive oxygen species using the method of chemiluminescent analysis. The emulsion was shown to suppress the neutrophil responses to phorbol-12-myristate-13-acetate in a dose-dependent manner. No inhibition of the activity of neutrophils in the presence of the emulsion was observed in N-formylmethionylleucylphenylalanine stimulated cells. The data obtained indirectly confirm the suggestion that the perfluoride emulsion inhibits neutrophil NADPH oxidase activity. In the presence of the perfluoride emulsion, myeloperoxidase plays a more important role in the generation of luminescent responses in both N-formylmethionylleucylphenylalanine- and phorbol-12-myristate-13-acetate-stimulated neutrophils. The effect of perfluoride emulsion results in the preferential myeloperoxidase-produced generation of reactive oxygen species in the neutrophil respiratory burst.

[Role of phospholipase A2 and epoxygenase in inhibition of respiration burst in neutrophils by low intensity radiation of extremely high frequency]. / Rol' fosfolipazy A2 i époksigenazy v ingibirovanii respiratornogo vzryva neitrofilov nizkointensivnym élektromagnitnym izlucheniem kraine vysokoi chastoty.

The role of some components of the phospholipid metabolism in the activation of neutrophil respiratory burst and its inhibition by electromagnetic radiation (EMR) of extremely high frequencies (EHF) was studied. It was shown that EHF EMR has effect on cells with a high sensitivity to the inhibitor of phospholipase A2 4-bromophenacyl bromide. However, againsts the background of the inhibitor, the effect of EHF EMR was not observed on cells with either high or low sensitivity to the inhibitor. EHF EMR was also inefficient with cells pretreated with proadifen, an inhibitor of epoxygenase (cytochrome P-450). The results obtained suggest that the effect of EHF EMR manifests itself in cells with a high activity of phospholipase A2 and is realized with the participation of epoxygenase metabolites of arachidonic acid.

[Millemetre waves inhibit the synergistic effect of calcium ionophore A23187 and phorbol ester in neutrophil respiratory burst]. / Millimetrovye volny ingibiruiut sinergicheskii effekt kal'tsievogo ionofora A23187 i forbolovogo efira v aktivatsii respiratornogo vzryva neitrofilov.

The effect of extremely high frequency electromagnetic field (mm-waves) on respiratory burst of neutrophils was studied. The peritoneal evoked neutrophils of the mice (NMRI line) were used. The production of reactive oxygen species was estimated by luminol-dependent chemiluminescence technique. Cells were irradiated by the mm-waves of 41. 95 GHz in the far field zone of the channel radiator during 20 min. Absorbed energy flux density was 150 microW/cm2. The irradiation was carried out at different concentrations of calcium ionophore A23187 and then neutrophils were stimulated by phorbol 12-myristate 13-acetate (PMA) 1 microM, activator of PKC. At irradiation of neutrophils the synergistic action of A23187 and PMA was not changed at low concentration of ionophore 10 nM-0.5 microM and was suppressed at high concentrations 0.5-10 microM. The largest inhibition of about 60% was obtained at the concentration of A23187 20 microM. The effect of mm-waves was not found under exposure in Ca(2+)-free medium for all used A23187 concentrations. We suggest that the mm-wave effect on the production of reactive oxygen species by neutrophils is determined by the influx of extracellular Ca2+ and PKC.