[Influence of polymicroelement preparation esmin on hydrogen sulfide levels and indices of pro- and antioxidant system in the rat myocardium of different age].

The influence of microelement preparation Esmin on hydrogen sulfide (H2S) levels, activity of H2S-producing enzymes and indices of pro-/antioxidant system in the myocardium of different age rats were investigated. In the process of aging the levels of H2S and activities of H2S-producing enzymes (cysteine aminotransferase, cystathionine-gamma-lyase) are reduced in the myocardium; the pro-/antioxidant balance is destabilized (NADPH-oxidase activity is increased and thioredoxin reductase activity is decreased). Esmin administration effectively reduces age-related changes in the myocardium of old rats: increases H2S levels and activity of H2S-producing enzymes, restores pro-/antioxidant balance.

Hydrogen sulfide: metabolism, biological and medical role.

Hydrogen sulfide (H2S) is a signaling molecule that is actively synthesized in the tissues and is involved in the regulation of vascular tone, neuromodulation, cytoprotection, inflammation and apoptosis. In recent years, new data on animal and human H2S metabolism and function under the effect of various endogenous and exogenous factors, including drugs were collected. This review is provided to introduce generalized information about the main and alternative H2S metabolism and regulation, peculiarities of transport, signaling, biological role and participation in pathogenesis. Submitted data describe H2S content and activity of H2S-synthesizing enzymes in different organs, H2S effect on blood coagulation and platelet aggregation based on our research results. The working classification of H2S metabolism modulators, which are used in biology and medicine, is proposed: 1) agents that increase H2S content in tissues (inorganic and organic H2S donors; H2S-synthesizing enzymes substrates and their derivatives, H2S-releasing drugs; agents that contain H2S-synthesizing enzymes cofactors and activators, agents that inhibit H2S utilization); 2) agents that reduce H2S content in tissues (specific and nonspecific inhibitors of H2S-synthesizing enzymes), 3) agents with uncertain impact on H2S metabolism (some medicines). It was demonstrated that vitamin-microelement and microelement complexes with H2S-synthesizing enzymes cofactors and activators represent a promising approach for H2S content correction in tissues.

[Effect of thiolactone homocysteine loading on adenosine metabolism in rats: relationship with platelet hyper-reactivity, correction of this metabolism disorders by vitamin-microelement complex].

Influence of DL-homocysteine thiolactone loading (100 mg/kg by intragastric administration for 28 days) on enzymes activity of adenylic nucleotide and adenosine metabolism in the blood serum, platelets and liver of rats was investigated. The relation between revealed disturbance and platelet hyper-reactivity was estimated. It was established, that apyrase and 5'-nucleotidase activities decreased and adenosine deaminase activity increased in platelets of the rats with hyperhomocysteinemia (HHC). HHC also interrupted adenosine production in the blood serum and liver in rats. Under this condition the platelet sensitivity to ADP-stimulation was significantly increased. Vitamin-microelement complex decreased HHC-induced disorder of adenosine metabolism and prevented platelet hyper-reactivity formation. In vitro homocysteine inhibited platelet hydrolysis of ADP and AMP in a dose-dependent manner and this effect reduced in the presence of hydrogen sulfide donor NaHS.

[Influence of hydrogen sulfide, dithionite, sulfite, thiosulfate and sulfate anions on human platelet aggregation].

The influence of hydrogen sulfide, dithionite, sulfite, thiosulfate, and sulfate anions on human platelet aggregation was investigated in vitro. It was established that sulfite, thiosulfate, and sulfate did not influence the platelet aggregation induced by ADP, collagen, or epinephrine in the concentrations range 10-1000 microM. Hydrogen sulfide and dithionite inhibited platelet aggregation induced by ADF or collagen in a dose-dependent manner. The action of hydrogen sulfide began in concentration of 100 microM and the action of dithionite began in concentration of 1000 microM. They did not influence epinephrine-induced platelet aggregation.

[Effect of homocysteine, cysteine, and their derivatives on the platelet link of hemostasis system].

The influence of homocysteine, homocysteine thiolactone, cysteine and their derivatives on activation and aggregation of human platelets was investigated using the model systems in vitro. It was established that homocysteine and cysteine increased platelet aggregation induced by ADP, epinephrine, or collagen. Their action began in a range of concentrations such as their physiological blood levels (10 microM) and was increasing with the rise of their concentrations. Cysteine increased ADP-induced platelet aggregation, hardly any affect on epinephrine-induced platelet aggregation and depressed collagen-induced platelet aggregation in the highest concentration (1000 microM). Their disulfides and thioethers did not influence platelet aggregation.

[Effect of proteins from the Agkistrodon blomhoffii ussuriensis snake venom on platelets in the hemostasis system].

Influence of proteins from the Agkistrodon blomhoffii ussuriensis snake venom on platelet activation and aggregation was developed on different model systems in vitro. It was shown that novel disintegrin (Blomus-B) and phospholipase A2 (Blopholipase) from the venom, activated platelets and inhibited their aggregation. Fibrino(geno)lityc enzyme (Blomulyse) does not activate platelets and has no effect on their aggregation stimulated by collagen, but inhibit ADP and adrenalin-stimulated platelet aggregation. Thrombin-like enzyme (Ancistron-Bu) activates platelets but has no effect on their aggregation. Obtained proteins can be used under development of new antiplatelet agents and as instruments for detailed elaboration and deep investigation of processes which proceed with participation of platelets.

[Effect of soluble fibrin on the blood coagulation process and platelets aggregation].

The accumulation of soluble fibrin (SF) in the blood plasma causes acceleration of the final stage of blood coagulation. It increases functional activity of a hemostasis system platelet link, that is the precondition of thrombotic complication. Accumulation of SF in the blood plasma is accompanied by proportional reduction of coagulation time in ancistron and thrombin time tests, and also the intensification of platelets aggregation process. A conclusion was drawn that for early diagnostics of the DIC-syndrom it is expedient to carry out complex estimation of the hemostasis system with obligatory definition of the blood SF content, performance of ancistron and thrombin time tests, and also study of platelets aggregation.

[Characterization of platelets aggregation inhibitor from Agkistrodon blomhoffii ussuriensis snake venom].

Platelet aggregation inhibitor--"Blomus-B" from Agkistrodon blomhoffii ussuriensis venom has been isolated by affinity and ion-exchange chromatography. The purified inhibitor is a novel non-enzymatic single-chain protein with molecular weigth of 13 kDa. "Blomus-B" causes a change of platelets shape and takes effect on ADP- and adrenalin-induced platelet aggregation.