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G V Donchenko

Publications and source records attributed to G V Donchenko.

At least 19 recordsLinked to original sources
PubMed2006

[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. Taking into account the forthcoming 20th anniversary of Chernobyl disarter, the authors of the come back to considering the obtained data in hope to atlract attention of medical scientific and public to the remained unsolved problems of micronutrient deficiency.

Adult↗
PubMed1999

Chemiluminescence determination of the in vivo and in vitro antioxidant activity of RoseOx and carnosic acid.

Lipid free-radical oxidation has been studied in vivo in the mitochondrial fractions of the liver of rats fed RoseOx (carnosic acid nutritional supplement) by measuring chemiluminescence. The kinetics of the lipid chemiluminescence in rats fed RoseOx are significantly different from those of the control. The intensity of the chemiluminescence fast flash decreases by 45% (p < 0.01), which indicates a reduction of lipid peroxides. The time between fast and slow flashes increases by 96% (p < 0.05), which indicates a higher content of antioxidants in the lipid membrane. The in vitro experiments in rat liver mitochondrial fraction display more effective antioxidant action of alpha-tocopherol in 1 microM concentration than 1 microM carnosic acid by an increase of the time between fast and slow chemiluminescence flashes (p < 0.01). However, the higher antioxidant activity of 1 microM carnosic acid by a decrease of intensity of the chemiluminescence fast (p < 0.05) and slow (p < 0.05) flashes in comparison with alpha-tocopherol is revealed in these experimental conditions in vitro. Carnosic acid has antioxidant effects on homogeneous oxidation in vitro as well. The chemiluminescence of methyl oleate initiated by 2,2'-azobis(2-methylpropionitrile) decreases by 25% (p < 0.01) in the presence of 13.5 microM carnosic acid. 13.5 microM alpha-tocopherol decreases the methyl oleate chemiluminescence by 45%. A higher antioxidant activity of alpha-tocopherol in comparison with carnosic acid (p < 0.001) is found in this system. These results indicate that RoseOx reduces free-radical-induced lipid peroxidation in vivo. In vitro data show that carnosic acid has direct action as an antioxidant, rather than as a membrane-structure modifier.

Abietanes↗
PubMed1997

Tocopherol modulates the effects of A23187, verapamil, and phorbol myristate acetate on RNA-polymerase activity of isolated rat liver nuclei.

Preincubation of rat liver nuclei with tocopherol decreased inhibition of RNA-polymerase activity of isolated rat liver nuclei by A23187, verapamil, and phorbol myristate acetate (PMA). In nuclei of vitamin E-deficient rats, A23187, verapamil, and PMA did not inhibit label incorporation into RNA with and without tocopherol. A23187, verapamil, and PMA did not inhibit the activity of nuclei treated with 1% Triton X-100; tocopherol activated RNA synthesis but co-administration of A23187 or verapamil and tocopherol had no effect and the combination of tocopherol and PMA inhibited RNA-polymerase activity by 25%. The effect of the combination of verapamil and PMA in the presence of free tocopherol was different from the effect of these compounds assayed in the presence of the complex of tocopherol with tocopherol-binding protein.

Animals↗
PubMed1994

[Effect of alpha-tocopherol and ubiquinone on mitochondrial RNA polymerase activity. The role of tocopherol-binding proteins].

It has been shown that alpha-tocopherol within the complex with tocopherol-binding proteins, in contrast with free tocopherol, decreases the RNA-polymerase activity in isolated rat liver mitochondria. Both free and complexed to proteins alpha-tocopherol increases the RNA-polymerase activity in isolated nuclei. The effect of alpha-tocopherol is conditioned mostly by the nature of the tocopherol-binding proteins. It has been established that ubiquinone complexed to tocopherol-binding proteins from mitochondria can also change the level of RNA synthesis. The effect of alpha-tocopherol and ubiquinone are not additive.

Animals↗
PubMed1994

[Interconnection of poly-ADP-ribosylation of histones and NAD level in rat liver during repair of induced DNA damage].

The changes in the DNA single strands induced by MNU and the levels of poly(ADP)ribosylation of the histone fractions have been studied under conditions of increased NAD content in rat liver during the recovery incubation of tissue in Hank's solution at 37 degrees C. In the presence of high (in the physiological range) NAD concentrations the DNA repair was more active in comparison with the control. This process was accompanied by activation of poly(ADP)ribosylation of predominantly core histone fractions.

Animals↗
PubMed1993

[Participation of tocopherol and its analogs in lipid peroxidation processes and electron transport in rat liver mitochondria in vivo].

The effects of vitamin E and its analogs--alpha-tocopheryl acetate with a shortened up to six carbon atoms side chain carrying a saturated and an unsaturated bonds at the chain terminus, alpha-tocopherol and alpha-tocopheryl quinone devoid of the side chain--on the rate of malonic dialdehyde formation, the diene conjugate and total lipid content in the liver as well as the activity of the respiratory chain enzymes--succinate--and NADH-dehydrogenase, succinate- and NADH-ubiquinone reductase, as well as the vitamin E and ubiquinone content in the liver mitochondria of vitamin E-deficient rats in vivo have been investigated. It has been found that alpha-tocopheryl acetate with a shortened (up to C6) side chain carrying a saturated bond at the chain terminus is the most effective analog of tocopherol. Further reduction of the tocopherol side chain or tocopherol conversion into quinone causes a decrease in their tocopherol activity.

Animals↗
PubMed1991

[Effect of vitamin E on transcription in isolated nuclei and rat liver chromatin in normal status and in E-hypovitaminosis].

The effect of alpha-tocopherol on the RNA-polymerase activity in isolated rat nuclei and chromatin from normal and E-deficient rats and the possible role of tocopherol-binding proteins in this process were studied. Some differences in the RNA-polymerase activities of the nuclei were found; however, in vitro added alpha-tocopherol had no effect on the level of the label incorporation into RNA. No effect of alpha-tocopherol on this process was observed after addition of cytosol either. Analysis of chromatins from normal and E-deficient rats revealed no differences in their RNA-polymerase activities. In vitro added alpha-tocopherol increased the RNA-polymerase activity of normal (but not of vitamin E-deficient) rats. Some differences in the RNA-polymerase activities were noted after addition to the incubation medium of the Triton X-100-solubilized nuclear fraction specifically binding alpha-tocopherol. This effect was enhanced in the presence of exogenous alpha-tocopherol. The susceptibility of chromatin from normal and E-deficient rats to DNAse I hydrolysis was also found to be different. It was concluded that vitamin E can influence the RNA-polymerase activity of the nuclei and chromatin as well as the chromatin structure and that alpha-tocopherol-binding proteins are necessary for the vitamin E effect on the RNA-polymerase activity to be manifested.

Animals↗
PubMed1991

[The role of vitamin E in the biosynthesis of ubiquinone (Q) and ubichromenol (QC) in rat liver].

Some peculiarities of ubiquinone (Q) biosynthesis in the livers of vitamin E-deficient rats induced in vitro by alpha-tocopherol and S-adenosylmethionine (SAM) were investigated. When [C3H3]SAM was used as a precursor, alpha-tocopherol added to the sample induced a marked elevation of the content of Q concomitantly with a drastic increase (2.82-fold) of specific radioactivity of Q in the liver as compared to control. Under identical conditions with 2-14C sodium acetate as precursor, exogenous alpha-tocopherol increased the content (by 31.4%) and specific radioactivity (by 65.2%) of Q in experimental samples, whereas the corresponding parameters of ubichromenol (QC) were essentially unchanged. SAM added to the incubation medium caused a marked increase in the content and specific radioactivity of both Q and QC as compared to control. Similar, and even more conspicuous changes were observed after combined administration of alpha-tocopherol and SAM. The role of vitamin E in the activation of methylation reactions at terminal steps of Q and QC biosynthesis in rat liver is discussed.

Animals↗
PubMed1989

[NAD participation in protecting DNA from damaging factors].

It was found that autolytic degradation of DNA during the isolation of nuclei under conditions of an in situ stimulated NAD biosynthesis is decreased to 2.5% in comparison with 5.2% in control. The increase in the NAD-pyrophosphorylase activity and the intranuclear content of NAD was almost 3-fold, whereas the amount of the acid-soluble DNA material was decreased 2-fold. The degree of DNA damage was increased up to 23% after induction with ethidium bromide. Under these conditions a preliminary in vivo stimulation of NAD biosynthesis by nicotinamide diminished the amount of the acid-soluble material. The levels of intranuclear NAD as well as the NAD-pyrophosphorylase and poly-(ADP-riboso)polymerase activities were essentially affected.

Animals↗
PubMed1989

[Solubilization of the central benzodiazepine receptor and study of its interaction with nicotinamide].

It was shown that nicotinamide and NAD inhibit the specific binding of [3H]flunitrazepam to benzdiazepine receptors without causing a direct influence of gamma-aminobutyric acid (GABA) receptors. The GABA-benzdiazepine complex was separated by solubilization with 0.5% lubrol PX. The solubilized preparations contain the binding sites for [3H]flunitrazepam alone (Kd = 5.9 nm). The Kd value for the membrane-bound benzdiazepine receptor is 2.9 nM. NAD inhibited the specific binding of [3H]flunitrazepam to the solubilized membrane preparation when used at concentrations by several orders of magnitude lower than that of nicotinamide. Using gel filtration on Sepharose 6B-CL, the molecular mass of the soluble benzdiazepine receptor protein was determined.

Animals↗
PubMed1989

[Blood vitamin A contents in patients with stomach cancer].

Fluorimetric method was used to measure preoperative blood plasma-vitamin A level in 100 gastric cancer patients and 64 healthy controls. The data obtained were analyzed versus site, stage and anatomic growth pattern of tumor. Vitamin A level was found to significantly decrease in 66% of gastric cancer patients, these changes being the most apparent in stage III tumor involvement of two segments of the stomach and endophytic type of growth. It is recommended that measures to correct blood plasma-vitamin A deficiency be taken in stomach cancer patients throughout treatment period.

Adult↗
PubMed1988

[Role of the cytosolic factor in the interaction of [3H] alpha-tocopherol with rat liver nuclei].

A protein fraction (Mr = 30-70 kD) specifically binding [3H]alpha-tocopherol was isolated from rat liver cytosol. Using high performance ion exchange chromatography, this fraction was separated into acid and alkaline protein subfractions. Acid proteins make up to 41% of the total protein pool and they bind the label 8 times more intensively than the alkaline ones. Cytosol and its protein fraction with an average molecular mass increase 2.2-2.5-fold the binding of labeled vitamin E to isolated liver nuclei. It is concluded that the cytosolic proteins having a medium molecular mass are involved in tocopherol interaction with the nuclei.

Animals↗
PubMed1987

[Isolation and various properties of thiamine-binding protein from synaptosomes in the rat brain].

A thiamine-binding protein (ThBP) with a specific activity of 8.21 nmoles/mg protein was isolated from rat brain synaptosomes by affinity chromatography and gel filtration on Sephadex G-200. The protein was purified 746-fold with a 40.5% yield. ThBP was homogeneous during sodium dodecyl sulfate gel electrophoresis; its molecular mass was determined by gel filtration on Sephadex G-200 and by sodium dodecyl sulfate gel electrophoresis and was equal to 107 and 103 kD, respectively. The pH optimum for the binding is 8.35. When the ability of ThBP to bind thiamine phosphates was tested, the latter decreased in the following order: thiamine monophosphate greater than thiamine triphosphate greater than greater than thiamine diphosphate.

Animals↗
PubMed1983

[Comparative study of the effects of alpha-tocopherol and a synthetic antioxidant on respiration and oxidative phosphorylation in rat liver mitochondria].

In order to decide whether vitamin E action on ubiquinone-dependent enzymatic systems of mitochondria and on ubiquinone metabolism consisting in its antioxidative function, the effects of alpha-tocopherol and the most effective synthetic antioxidant, chlorohydrate 2-ethyl-6-methyl-3-hydroxypyridine, were compared. It was shown that the contents of vitamin E and ubiquinone as well as the activities of succinate- and NADH-ubiquinone reductase, succinate- and NADH-dehydrogenases in liver mitochondria are increased and the levels of ATP, adenine nucleotides and phosphate potential in the livers of vitamin E-deficient rats are elevated 3 hours after alpha-tocopherol injection (5 micrograms per 1 g of body weight). The synthetic antioxidant injected under identical conditions at a dose of 50 micrograms per 1 g of body weight did not change the ubiquinone content or the enzymatic activities, but considerably enhanced the ATP level. The same antioxidant when injected at a dose of 105 micrograms per 1 g of body weight did not significantly affect the parameters under study but decreased the activity of succinate-ubiquinone reductase. Thus, the role of vitamin E in oxidative phosphorylation may not only consist in its antioxidant action and is largely due to the regulation of metabolism and functioning of ubiquinone.

Adenine Nucleotides↗
PubMed1982

[Ubiquinone and vitamin E content in rat tissues in experimental focal myocarditis and hypoxic hypoxia].

The content of ubiquinone and vitamin E in liver, heart, kidney and muscle tissues has been found to vary in experimental focal myocarditis and acute hypoxic hypoxia. These compounds have been demonstrated to accumulate in myocardial mitochondria, which is likely to be related to both interstitial and inter-organ redistribution having a compensatory-adaptation importance. In the pathology under study, the myocardium demonstrates a greater intensity and more remarkable line of changes in the content of vitamin E and ubiquinone. It is suggested that these substances contribute to the increased body resistance to hypoxic exposures of varying genesis.

Animals↗
PubMed1979

[Effects of alpha-tocopherol derivatives on natural quinone levels in the tissues of vitamin E deficient rats].

The effects of alpha-tocopherol and its derivatives (alpha-tocopherylquinone, its short-chained analog--alpha-tocopheronolactone--and short-chained alpha-tocopherylacetate) on the levels of ubiquinone, its cyclic isomer--ubichromenol--and vitamin E in the liver and heart of vitamin E-deficient rats were studied. After injection of alpha-tocopherol derivatives the levels of ubichromenol and ubiquinone in rat liver and heart were increased, while their ratio was decreased. alpha-Tocopheronolactone was found to exert the strongest action, which is probably due to its direct effect on ubiquinone metabolism in rat tissues.

Animals↗