[Effects of alpha-tocopherol and its anologues on rat thymocytes programmed death induced by protein kinase inhibitors].

It is established that alpha-tocopherol (alpha-TPh) shows cytoprotective effect at the induction of rats' thymocytes apoptosis by endocellular protein kinase inhibitors--staurosporine and phorbol ether in high concentration, and also on necrosis of the cells caused by sphyngosine. The effect of alpha-TPh on thymocytes death caused by protein phosphatase type 2A inhibitor ocadaic acid is much less expressed. The obtained data testify that the known ability of alpha-TPh to the inhibition of PKC and to the activation of protein phosphatase type 2A is not the main mechanism of its cytoprotective action.

[Oxidized derivatives of thiamine: formation, properties, biological role].

The data available in literature about formation, properties, possible biological role and practical application of the oxidized derivatives of B1 vitamin (thiamine) is first generalized and analysed in the review. It is known that at the values of pH > 7.0 the molecule of thiamine is able to undergo two-phase reaction of opening of thiazole ring with formation of anion of thiol form of thiamine and unstable tricyclic form.

[Effect of precursors and modulators of coenzyme Q biosynthesis on the heart mitochondria function in aged rats].

Our research demonstrate that ageing leads to changes in activity of electron-transporting enzyme complexes in myocardial mitochondria of old rats and to increased sensitivity of mitochondrial permeability transition pore to inductors of its opening--Ca2+ and phenylarsine oxide. We also observed activation of lipid and protein free-radical peroxidation processes. Administration of a complex of biologically active substances that included precursors and modulators of coenzyme Q biosynthesis (alpha-tocopherol acetate, 4-hydroxybenzoic acid, and methionine) we observed the increase in coenzyme Q content, correction of functional activity of mitochondrial electron-transport chain enzyme complexes, the decrease in intensivity of lipid and protein free-radical peroxidation in the heart and the decrease in sensitivity of mitochondrial permeability transition pore to inductors of its opening.

[Existence of two different active sites on thiamine binding protein in plasma membranes of synaptosomes].

The current work is aimed at understanding the structure and functionality of thiamine binding protein (TBP) in neural cells plasma membranes. The influence of thiamine triphosphate on thiamine binding by TBP in synaptic plasma membranes (SPM) isolated from the rat brain was investigated. It was shown that thiamine triphosphate inhibits thiamine binding activity of SPM in concurrent manner (K(i) = 1.

[Cytotoxicity of troglitazone, structural analogue of alpha-tocopherol is mediated by inhibition of NAD(P)H:quinone oxidoreductase].

It is established, that alpha-tocopherol and pioglitazone in concentration up to 100 microM did not change the rat thymocytes viability while troglitazone and alpha-tocopherol with a short side chain up to 6 atoms of carbon (alpha-tocopherol C6) have the expressed cytotoxic effect. This is the first report demonstrating that troglitazone and alpha-tocopherol C6, unlike a-tocopherol and pioglitazone substantially inhibited the activity of NAD(P)H:quinone oxidoreductase (DT-diaphorase) and this effect is increased with specific DT-diaphorase inhibitor, dicoumarol. Based on these observations, we generalize that cytotoxic action of troglitazone and alpha-tocopherol C6 is connected with the presence in their structure of chroman ring with a lateral chain modified in relation to alpha-tocopherol and is mediated by inhibition of DT-diaphorase, a detoxifying enzyme of xenobiotics.

[Thiamine metabolism disorders in the rat brain in experimental alcoholism and a possibility of their correction by vitamin E].

The influence of the chronic consumption of alcohol on biochemical reactions of thiamine metabolism in the rat brain is investigated. It is shown that the content of thiamine diphosphate (ThDP) in the brain tissue does not change at these conditions, though there is an essential decrease in the thiamine-kinase activity. The ability of the isolated nerve terminals (synaptosomes) to absorb labelled thiamine also decreases under this condition.

[Role of alpha-tocopherol in oxidative stress of rat thymocytes induced by hydrogen peroxide and menadione].

T paper deals with studying the effect of alpha-tocopherol and its analogues (alpha-tocopheryl acetate and alpha-tocopheryl quinine) showing no antioxidant properties on rat thymocytes survival and intracellular content of reactive oxygen species (ROS) at H2O2 and menadione-induced oxidative stress. It is established, that the ability of alpha-tocopherol to inhibit the thymocytes destruction induced by the development of oxidative stress is insignificant. It does not depend on the presence of free OH-group in the structure of alpha-tocopherol molecule responsible for development of antioxidant properties, and does not correlate with its influence on intracellular ROS content.

[Characteristic metabolic disturbances in the rat tissues caused by long-term use of alcohol].

In the researches carried out on rats with models of chronic alcoholism and alcohol abstinence the most vulnerable to chronic action of alcohol biochemical parameters are revealed: a level of reduced glutathione (it was estimated by the content of free SH-groups in tissues), the content of thiamine diphosphate and thiaminekinase activity in a brain, the content of folic acid in the blood, the content of ubiquinone in the cardiac muscle, RNA/DNA relation in the liver. The data obtained demonstrate first of all the negative influence of alcohol on metabolism of sulfur-containing substances and processes of transmethylation. The results of our investigation have also shown that the part of metabolic changes caused by long-term usage of alcohol, can be caused by direct influence of ethanol or its metabolites on those or other enzymatic proteins or receptors, and their functions can quickly be normalized after the abolition of alcohol (NAD+ contents, alpha-ketoglutarate dehydrogenase activity and some others).

[To the 20th anniversary of the Chornobyl accident study of vitamin status and provision with micro- and macroelements of limited groups of people at different time periods since the accident at Chornobyl nuclear power plant].

Results of the study of the provision with vitamins and some micro- and macroelements of limited groups of people, who suffered from the accident at the Chornobyl nuclear power plant (ChNPP), which have been carried out by Ukrainian and Russian scientists during various periods after the accident, are generalized in the paper. Persons which participated in liquidation of the accident and lived during the accident in the territory, adjoining to Pripyat (the Kyiv region, town of Slavutich), people which worked at the object "Shelter" and ChNPP were involved in the inspection. It was noted, that in 1-4 years after the ChNPP accident in blood of liquidators the biochemical parameters displaying security of their organism by vitamins A and B1, remain lower in comparison with the same parameters in a group of relatively healthy persons which were not affected by the accident (control), that testifies to stable metabolic disturbance in the organism of people under irradiation influence.

[To 20-years anniversary of Chernobyl catastrophe: an attempt to study the vitamin, calcium, iron and selenium status of children and adult population in Slavutich and to correct elicited deficiencies].

The article concisely illustrates the vitamin and mineral state of population of town of Slavutich, including personal of Chernobyl Nuclear Power Station, children of pre-school age and pregnancy women, studied in 1992. Vitamins and minerals deficiency in the main of C and B vitamins and selenium was revealed in all the studied groups. Appropriate measures were developed and introduced to eliminate the detected dusturbances; but however some unsolved problems remained.

[Cytotoxic effect of vitamin E short-chain derivatives on rat thymocytes].

It is established, that alpha-tocopherol, alpha-tocopheryl acetate and tocopheryl quinone with carbon lateral chains shortened to 6 atoms inhibited the viability of primary culture rats thymocytes in a dose-dependent manner. Absence of the DNA internucleosomal degradation side by side with cytosolic lactate-dehydrogenase outlet from the cells testifies to the benefit of necrotic way of thymocytes destruction. The outlet from cells of acid phosphatase, lysosomal marker enzyme, testifies to destabilization of lysosomal membranes by the researched compounds.

[Effect of alpha-tocopherol and its derivatives on actinomycin D induced apoptosis of rat thymocytes].

The induction of rat thymocyte apoptosis by actinomycin D was associated with the increased caspase-3 activity and DNA fragmentation, the both effects were attenuated by alpha-tocopherol. Apoptosis was also decreased by alpha-tocopheryl acetate, but these suppressive effects were less than those of alpha-tocopherol. Tocopheryl quinone had no pronounced antiapoptotic effect.

[Viruses as the etiological factor of type 1 diabetes. Animal models].

Type 1 diabetes (TID) results from the destruction of pancreatic beta-cells. In spite of genetic pre-disposition, being the major component for the development of this type of diabetes, nongenetic factors also play an important role in the disease development. Among these factors viruses are implicated in the pathogenesis of TID.

[Effect of iodine and cobalt salts on content of biologically active substances in spirulina biomass].

Production technology of iodinized spirulina biomass at vertical panel airlifted photobioreactor has been developed. The influence of different concentrations of iodine ions at certain combinations with cobalt ions on iodine-accumulative properties of spirulina has been studied. It has been shown that it is possible to obtain spirulina biomass containing certain amount of organically bound iodine by varying cobalt and iodine ions combinations and by staged addition of ions to incubation medium.

[Effect of alpha-tocopherol on apoptosis and necrosis of rat thymocytes induced by calcium ionophore A23187 in various concentrations].

It has been established that alpha-tocopherol prevented rat thymocytes apoptotic death induced by low concentration (250 nM) of calcium ionophore A23187. When necrotic cell death was induced high concentration (10 microM) of calcium ionophore A23187 alpha-tocopherol was able to alter necrosis to apoptosis. It was proposed that such effect can be explained by the ability of alpha-tocopherol to prevent the mitochondrial permeability transition--a key event in apoptosis and necrosis induction.

Poly(ADP-ribosyl)ation enhancement in brain cell nuclei is associated with diabetic neuropathy.

Unlabelled: The study has been undertaken to evaluate the effect of streptozotocin (STZ)-induced diabetes on rat brain poly(ADP-ribose)polymerase (Parp) activity and assess whether and how a Parp inhibitor, nicotinamide (NAm), may potentially regulate the diabetes-induced changes. Experiments were carried out after 4 weeks of diabetes duration in rats treated with or without NAm (100 or 200 mg kg(-1) day(-1), injected intraperitonally for 2 weeks). Assays were performed in purified brain cell nuclei to determine Parp activity by incorporation of radiolabeled ADP-ribose moieties from nicotinamide adenine dinucleotide (NAD+) into nuclear proteins.

[Intracellular localization of thiamine-binding proteins in the liver and kidneys of rats].

The distribution of thiamine-binding and thiamine triphosphatase activity typical of thiamine-binding proteins was studied in intracellular structures of rats liver and kidneys. It was found that the fraction of microsomes has the highest rate of specific thiamine-binding activity amide fractions of subcellular structures that was isolated using differential centrifugation in the both organs. Hydrolysis of thiamine triphosphate (pH 7.

[Vitamin E and apoptosis].

The literature data concerning the participation of tocopherol in apoptosis are discussed. Acting as antioxidant this vitamin exerts a complex effect on apoptosis mechanisms. Its action on this process is caused by involvement of some different mechanisms transducing the apoptotic signal.

[Antihypoxic effect of vitamin E and its derivative in rats under modeling of hypoxic conditions of different origin].

The increase of ubiquinone content in myocardial mitochondria and succinateubiquinone reductase activity in rat blood leucocytes under hypoxic hypoxia and acute microfocal myocardial damage [table: see text] have been shown. At the same time the succinateubiquinone reductase activity of rat myocardial mitochondria do not change substantially. We simultaneously observe the dramatic drop in NADH-ubiquinone reductase activity under experimental myocarditis.

[Comparative study of the effect of alpha-tocopherol, its synthetic metabolite and ionol on dexamethasone-induced apoptosis in rat thymocytes].

alpha-Tocopherol was found to decrease the level of rat thymocytes DNA fragmentation and to increase the viability of these cells under apoptosis induction by dexamethazone. So the antiapoptotic role of this vitamin is suggested. In contrast to alpha-tocopherol synthetic antioxidant ionol and alpha-tocopherylacetate, contained only 6 carbon atoms in its isoprenoid side chain caused the cell death from necrosis.

[Ubiquinone content and function in the mitochondrial electron transport chain in experimental focal myocarditis in rats].

The content of ubiquinone and vitamin E and functioning of ubiquinone-dependent enzyme systems in myocardial mitochondria and blood leucocytes of rats under experimental microfocal myocard damage, and the effect of vitamin E under given pathology have been studied. Direct dependence between the content of ubiquinone, vitamin E and activity of succinateubiquinone reductase system of blood leucocytes has been established. Vitamin E demonstrates the normalizing effect on the subjects of our study.

[Vitamin D3 and 20-hydroxyecdysone -- inhibitors of free radical lipid oxidation during D-hypervitaminosis].

Under D-hypovitaminosis (control) conditions the statistically reliable increase of blood serum lipids free radical oxidation was revealed in comparison with the intact animals. Administration of vitamin D3 to the animals suffering from D-hypovitaminosis leads for statistically reliable decrease of blood serum lipids free radical oxidation, while 20-hydroxyecdysone in quantity of 0.02 mg per 1 kg of the animal body weight displays the antioxidative properties.

[alpha-Tocopherol increases phosphorylation of rat nuclear proteins, catalyzed by protein kinase C].

alpha-Tocopherol added in vivo increased protein kinase C--dependent phosphorylation of rat liver nuclei proteins. Such effect of tocopherol was found also after the addition of sphingosine known as natural inhibitor of protein kinase C to incubation medium. The stimulation of phosphorilation was observed also after the addition of alpha-tocopherol to the Triton X-100 solubilized nuclear fraction which contained protein kinase C and tocopherol-binding proteins.

[Gene protective effect of the short-chain derivative of Vitamin E under the action of alkylating compounds].

The gene protective effect of the short chain derivative of vitamin E was investigated in rats intoxicated with embichin and cyclophosphamide. Prophylactic administration of tocopherol derivative for 14 days promotes reduction of the genome and chromosome disturbances in marrow cells caused by this compounds. Correcting influence of tocopherol derivative depends on chemical structure and biologic peculiarities of the alkylating compound.

[Provision of residents of the city of Kiev with vitamins C and B1. Effectiveness of a complex vitamin-mineral preparation in preventing spring vitamin deficiencies].

The investigation was conducted on provision with vitamins C and B1 of Kyiv inhabitants limited contingent at spring period and efficiency of complex vitamin-mineral preparations in normalisation of the vitamins level in blood of human-subjects. The deficit of vitamin C in 54% and vitamin B1 in 18.5% of the investigated people was revealed.