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Biomedical subjects

G V Donchenko

Publications and source records attributed to G V Donchenko.

At least 37 records · Page 2Linked to original sources
PubMed1978

[Interconversions of ubiquinone and ubichromenol in rat liver under the effect of alpha-tocopherol].

Incubation of ground liver preparation isolated from vitamin E-deficient rats resulted in correlated in time changes of ubiquinone and ubichromenol contents and their ration in tissues. A suggestion is made on the possibility of ubiquinone and ubichromenol interconversions and of the existence of a system controlling (depending on a functional state of the organism) a certain ratio of the quinones contents in animal tissues. Possible biochemical role of ubichromenol in animals is discussed.

Animals↗
PubMedDate not supplied

[In vitro metabolism of ubiquinone and ubichromenol in the livers of rats with avitaminosis E during individual and combined addition of alpha-tocopherol and phenylalanine].

A maximal incorporation of 2-14C-acetate into ubiquinone and ubichromenol was found within 3 hrs if liver tissue homogenate of E-avitaminous rats was incubated for 4 hrs. Phenylalanine, added to the mixture, stimulated the biosynthesis of ubiquinone and ubichromenol in the liver tissue preparations. alpha-Tocopherol caused an increase in biosynthesis of ubiquinone and a decrease in the rate of ubichromenol biosynthesis within 1 hr and 3 hrs of incubation in vitro. The combined addition of phenylalanine and alpha-tocopherol, almost without exceptions, increased the effect of alpha-tocopherol on biosynthesis of the substances studied. Interrelationship is discussed between vitamin E and ubiquinone and ubichromenol biosynthesis.

Animals↗
PubMedDate not supplied

[Relationship between values of antioxidant enzyme system activity in various tissues of intact rats].

It was studied the relation between activities of ferments an antioxidant system: of superoxide dismutase, catalase and GSH-peroxidase in the homogenates of livers, lungs and cerebrum of intact rats. When activities were brought to identical units of measurement, it was determined that relation of activities can see with a point to view of chemical kinetics laws for consecutively-parallel reactions. It is followed from the result that the activity of catalase livers can be explained by the participation of catalases in other reactions, which were connected with forming a hydrogen peroxide. From the relations between ferments of antioxidant system it was discovered that GSH-peroxidase is the most important antioxidant enzyme for the cerebrum. Data of the relation of activities ferments of antioxidant system are stipulated by the tissues particularities and they are reflected a contribution of every biocatalyst in that system.

Animals↗
PubMedDate not supplied

[Content of fat-soluble vitamins in human blood serum during the use of food additives with vitamin E and carotene of plant origin].

Vitamin E, A and carotene levels in blood serum of human that were affected by the definite irradiation doses accepting the admixtures of vitamin E and carotene preparations were estimated. The consuming of vitamin E increases vitamin E and A content in blood serum. While obtaining carotene significant increase of vitamin E and carotene content is observed, but it does not influence to vitamin A content. Simultaneous application of both preparations leads to vitamin E level growth being similar to persons, receiving only vitamin E; in this case the vitamin A and carotene content is increasing more actively and produces as early as in the month the carotene accumulation in blood serum. Along side with this the vitamin A content increases only in 3 month, and vitamin E practically does not change. Among estimated persons 45 years older revealed content of vitamin E increase in 3 month of both application of preparation. Application of vitamin E and carotene preparations have expressive positive change of fat-soluble vitamin status in blood serum.

Adult↗
PubMedDate not supplied

[Correction of diabetic neuropathies using aldose reductase inhibitors and pikamilon].

Streptosotocin-induced diabetes in rats is accompanied by the development of diabetic complications such as neuropathies. [2-14C]serotonin and [U-14C]GABA release from the neurotransmitter pre-loaded synaptosomes showed significant elevation. Aldose reductase inhibitors (AL-1576, sorbinil) administration leads to partial restoration of serotonin and GABA release, while picamilon restored only GABA release. It was shown that Na+,K(+)-ATPase activities decreased in synaptosomes, synaptic membranes and sciatic nerve of diabetic rats compared to control. Administration of AL-1576 normalized Na+, K(+)-ATPase activity, while sorbinil and picamilon less effectively. Sorbitol level are increased in streptozotocin-diabetic rats as compared to control. The picamilon and aldose reductase inhibitors administration to diabetic rats is accompanied by the partial reduction of brain sorbitol level. The findings confirm the important role of picamilon and aldose reductase inhibitors in the prevention and treatment of diabetic neuropathy.

Aldehyde Reductase↗
PubMedDate not supplied

[Effect of low doses of radiation on vitamin A and E levels in rat liver].

It has been established that under intake of small doses of 137Cs by rat for 9 months the radioactivity of whole rat body was increased in irregular manner. Under this condition the level of fat-soluble vitamins A and E is decreased and the decrease is well correlated with a level of radionuclide accumulation by rat's body. The possible causes of decrease of the vitamins A and E level under intake of small doses of radionuclide are discussed.

Animals↗
PubMedDate not supplied

[Antioxidant effect of 20-hydroxyecdysone in a model system].

Changes in the level of lipid free-radical oxidation in mitochondrial fraction at the presence of 20-hydroxyecdysone in 1, 2, 4, 6, 8 microM concentration with the help of a chemiluminescence (ChL) method were investigated in vitro. Statistically authentic reduction of ChL kinetic parameters--I(s) and tg alpha, at 20-hydroxyecdysone presence in concentration of 2 microM was found. 20-hydroxyecdysone administration in concentration 4 microM and more leads to the statistically authentic change of all four ChL parameters. The antioxidizing effect of 20-hydroxyecdysone was compared with action of such antioxidant as a hydroquinone. The higher activity of 20-hydroxyecdysone as an antioxidant in comparison with the hydroquinone was shown. For changes of all four measured kinetic parameters of ChL, concentration of the hydroquinone as much 2-fold than for 20-hydroxyecdysone is necessary. On the basis of our researches in the model system a conclusion was made that 20-hydroxyecdysone has an antioxidizing action on lipid free radical oxidation in mitochondrial fraction in dependents on concentration. 20-Hydroxyecdysone has antioxidizing properties directly, in these conditions in vitro, when its metabolites formation does not occur yet.

Animals↗
PubMedDate not supplied

[Effect of vitamin D3 on free-radical oxidation of lipids in low density lipoproteins in vitamin D deficiency].

The lipid free radical oxidation in low density lipoproteins was investigated on D-deficiency model in vivo. The processes of lipid free radical oxidative activation in low density lipoproteins at D-deficiency occurred. The chemiluminescence kinetic parameters: the maximum intensity of the first flash and inclination angle tangent of an ascending branch of the second flash grew at D-deficiency in comparison with control group (p < 0.02 and p < 0.05, respectively). At the same time, the vitamin D3 introduction to the experimental animals diet failed result statistically reliable inclination angle tangent of an ascending branch of the second flash was reduced (p < 0.02). Increase of the products reacting with thiobarbituric acid content in low density lipoproteins in D-deficiency conditions (p < 0.001) was found. Vitamin D3 introduction to the diet reduced quantity of products reacting with thiobarbituric acid in low density lipoproteins (p < 0.01). However, their level remained higher than for the control animals (p < 0.01) as established.

Animals↗
PubMedDate not supplied

[Placenta--a source of biologically active substances].

In the review there are some data displaying the scientific and patent literature presenting placenta as a rich source of some biologically active substances (BAS): proteins, lipids, enzymes, glycolipids and glycolipoproteins, hormones. This information is capable to be used while developing the techniques of BAS producing from placenta in order of creating the organospecific complex preparations with medically-preventive properties.

Biological Factors↗
PubMedDate not supplied

[Interaction of thiamine with rat brain synaptosomes].

Thiamine has been shown to be bound specifically by a synaptosomal plasmatic membrane and transported inside to the nervous ending. Apparent K[symbol: see text] and Km for processes of binding and transport have been determined as equal 2.34 +/- 0.55 MKM and 3.92 +/- 1.3 MKM, respectively. The thiamine uptake by the isolated nervous endings (synaptosomes) at its physiological concentration is reduced in presence of metabolic inhibitors and partially depends on Mg2+ and Ca2+ ions, that can testify about the interrelation between endogenic thiamine phosphorilation and its transport through the membrane. Thiamine binding with synaptosomes is inhibited by ouabain and neurotoxins such as, latrotoxin and most significantly--with veratridin; tetrodotoxin fail to be efficient practically. In the conditions of synaptic membranes depolarisation their ability to bind thiamine is reduced and output of already uptaken with synaptosomes thiamine is observed.

Animals↗
PubMedDate not supplied

[Characteristics of antioxidant properties of 20-hydroxyecdysone in low density lipoproteins by kinetic parameters of chemiluminescence].

20-Hydroxyecdysone is capable to terminate the lipid free-radical oxidation in low density lipoprotein in vitro as displayed by the kinetic chemiluminescence parameters. In concentrations interval from 2 x 10(-6) mol/l up to 8 x 10(-6) mol/l it statistically reliably reduces maximum of the first flash intensity of the low density lipoprotein Fe(2+)-initiated chemiluminescence. It testifies about Fe(2+)-initiated lipid peroxide process decomposition in low density lipoprotein slowing down by 20-hydroxyecdysone. In concentration of 20-hydroxyecdysone 8 x 10(-6) mol/l the statistically reliable reduction of angle tangent of an ascending branch of the second flash of low density lipoprotein Fe(2+)-initiated chemiluminescence was found. This is a result of free-radical lipid oxidation rate reduction in the low density lipoprotein at the 20-hydroxyeodysone presence. The equations of the kinetic parameters linear dependences Fe(2+)-initiated chemiluminescence in low density lipoprotein on the concentration of 20-hydroxyeodysone and hydroquinone have been received. The correlation factors in the interval from 0.8980 up to 0.6789 have been calculated. Thus, the assumption has been forwarded that 20-hydroxyeodysone has antioxidizing properties. However, its antioxidizing activity in free radical lipid oxidation of is low density lipoprotein is as less as for hydroquinone.

Animals↗
PubMedDate not supplied

[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. Supradin gave the best results among rest preparations ("Centrum", "Vitrum", "Duovit", "Multi-Tabs") in the normalization of the level of vitamin C and biologically-active form of thiamine (thiamindiphosphate) in the blood of investigated people.

Ascorbic Acid↗
PubMedDate not supplied

[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.

Animals↗
PubMedDate not supplied

[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. Its antioxidative effect is characterized by a statistically reliable increase of Tind chemiluminescence kinetical parameter as compared with the control. Under D-hypovitaminosis conditions in the mitochondrial membranes the products of lipids free radical oxidation--dien conjugates are accumulated. In the case of administrating to the animals suffering from D-hypovitaminosis D3 or 20-hydroxyecdysone these oxidation products are absent. 20-Hydroxyecdysone under these conditions have been revealed as inducing accumulation in the mitochondrial and microsomal membranes of the substances with lambda 225 nm.

Animals↗
PubMedDate not supplied

[Content of ubiquinone and ubichromenol in rat liver at various levels of vitamin E saturation of the body].

Ubiquinone and ubichromenol content was studied at different levels of organism supply with vitamin E. The content of these substances in the albino rat liver with vitamin E-deficiency is shown to decrease by 16 and 23%, respectively. The intravenous administration of alpha-tocopherol to the vitamin E-deficiency rats causes a gradual 45% increase in the ubiquinone content 4h after which remains at the same level for 8 h; the ubichromenol content 2 h latter is 1.7 times as high and then it lowers gradually up to the level in the avitaminous animals.

Animals↗
PubMedDate not supplied

[Incorporation of [3H]alpha-tocopherol into isolated nuclei and its binding by rat liver chromatin].

The investigation of inclusion of [3H]alpha-tocopherol to isolated rat liver nuclei has revealed its nonspecific character. The presence of cytosol is necessary for specific interaction of alpha-tocopherol with nuclei. After the centrifugation of preliminarily labeled chromatin the most quantity of tocopherol was bound with oligonucleosomes and pelleted chromatin. It is supposed, that the preservation of supernucleosomes level of chromatin folding was necessary for the interaction of alpha-tocopherol with chromatin.

Animals↗
PubMedDate not supplied

[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.

Animals↗