[Features of ozone effect on the oxygen-dependent blood processes under hypercapnia conditions]. / Osobennosti deistviia ozona na kislorodzavisimye protsessy krovi v usloviiakh giperkapnii.

The aim of this work is to study of ozone effect on blood oxygen-dependent processes under hypercapnia conditions. The studied blood samples are pretreated with a hypercapnic gas mixture followed by the addition of ozonized isotonic sodium chloride solution (with an ozone concentration of 6 mg/l), as well as gaseous transmitters donors, nitroglycerin and sodium hydrosulfide. It has been established that hypercapnia enhanced the ozone effect on the blood oxygen transport function and was characterized by the oxyhemoglobin dissociation curve shift to the right, also increased hydrogen sulfide synthesis and absence of changes in the nitrates/nitrites concentration. Under these conditions nitroglycerin and sodium hydrosulfide did not change the parameters of the blood gas transport function, but increased the level of nitrate/nitrite and hydrogen sulfide. Preliminary hypercapnia does not eliminate the activating effect of ozone on the free radical oxidation processes, and the addition of the applied gaseous transmitter donors does not contribute to the regulation of the studied parameters.

[Prooxidant-antioxidant balance depending on endothelial nitric oxide synthase G894T polymorphism]. / Prooksidantno-antioksidantnyi balans v zavisimosti ot polimorfizma G894T gena éndotelial'noi sintazy oksida azota.

The aim of the study was to assess the prooxidant-antioxidant balance depending on endothelial nitric oxide synthase G894T polymorphism. The frequency distribution of alleles and genotypes of G894T polymorphism, nitrite concentration, hydrogen sulphide, lipid peroxidation products (diene conjugates, malonic dialdehyde), antioxidants (reduced glutathione, catalase, ceruloplasmin, retinol) were determined in venous blood of healthy males. The incidence of the GG genotype was 49.1%, GT - 44.2%, TT - 6.7%. The level of malonic dialdehyde in erythrocytes with the GG genotype is 16.8% lower than in the genotype GT. The concentration of hydrogen sulphide in the blood with the GG genotype was 27.5 [18,2; 32,5] mM, GT - 28.6 [22.9; 33.8] mM, TT - 36.3 [33.8; 42.5] mM. The content of total nitrites in plasma with the GG genotype was 10.4 [9,0; 12,5] mM, GT - 10.4 [8.9; 11.8] mM, TT - 9.4 [8.8; 9.8] mM. The genotype GG causes a lower level of malonic dialdehyde in comparison with the heterozygous genotype. The G894T polymorphism allele T is associated with a low content of total nitrites in the plasma and a high concentration of hydrogen sulfide. The data obtained suggest that if the oxygen supply of the organism is impaired, the endothelial nitric oxide synthase G894T polymorphism may be important for the oxidative stress development.

[THE INFLUENCE OF CARBON MONOXIDE ON THE PARAMETERS OF PROOXIDANT-ANTIOXIDANT BALANCE DURING HEPATIC ISCHEMIA-REPERFUSION SYNDROME IN RATS].

The influence of carbon monoxide on the blood and liver prooxidant-antioxidant parameters: lipid peroxidation products (conjugated dienes, malondialdehyde, Schiff bases) and antioxidant system parameters (catalase, retinol, α-tocopherol, glutathione) were investigated in rats during hepatic ischemia-reperfusion. Hepatic ischemia was induced by Pringle maneuver for 30 min, reperfusion period was 120 min. It is detected, that hepatic ischemia-reperfusion leads to intensification of lipid peroxidation with declining of antioxidant defense. Infusion of the donor CO before reperfusion period improves the prooxidant-antioxidant balance in the blood and liver. In conclusion, CO increases the antioxidant activity of the blood and liver, decreases lipid peroxidation processes, that's correct oxidative damages during hepatic ischemia-reperfusion.

Thiamine triphosphate and thiamine triphosphatase activities: from bacteria to mammals.

In most organisms, the main form of thiamine is the coenzyme thiamine diphosphate. Thiamine triphosphate (ThTP) is also found in low amounts in most vertebrate tissues and can phosphorylate certain proteins. Here we show that ThTP exists not only in vertebrates but is present in bacteria, fungi, plants and invertebrates. Unexpectedly, we found that in Escherichia coli as well as in Arabidopsis thaliana, ThTP was synthesized only under particular circumstances such as hypoxia (E. coli) or withering (A. thaliana). In mammalian tissues, ThTP concentrations are regulated by a specific thiamine triphosphatase that we have recently characterized. This enzyme was found only in mammals. In other organisms, ThTP can be hydrolyzed by unspecific phosphohydrolases. The occurrence of ThTP from prokaryotes to mammals suggests that it may have a basic role in cell metabolism or cell signaling. A decreased content may contribute to the symptoms observed during thiamine deficiency.