Wyniki wyszukiwania

1

Inhibitory effect of quercetin on glycolysis in blood platelets

100%

Tomasiak M.

Applied Biology Communications. Lublin Scientific Center

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1992

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tom 02

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nr 1

2

Nitric oxide and platelet energy metabolism

86%

Tomasiak M., Stelmach H., Rusak T., Wysocka J.

Acta Biochimica Polonica

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2004

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tom 51

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nr 3

This study was undertaken to determine whether nitric oxide (NO) can affect platelet responses through the inhibition of energy production. It was found that NO donors: S-nitroso-.N-acetylpenicyllamine, SNAP, (5-50 uM) and sodium nitro- prusside, SNP, (5-100 uM) inhibited collagen- and ADP-induced aggregation of porcine platelets. The corresponding IC50 values for SNAP and SNP varied from 5 to 30 uM and from 9 to 75 uM, respectively. Collagen- and thrombin-induced platelet secretion was inhibited by SNAP (IC50 = 50 uM) and by SNP (IC50 = 100 uM). SNAP (20-100 uM), SNP (10-200 uM) and collagen (20 ug/ml) stimulated glycolysis in intact platelets. The degree of glycolysis stimulation exerted by NO donors was similar to that produced by respiratory chain inhibitors (cyanide and antimycin A) or uncouplers (2,4-dinitrophenol). Neither the NO donors nor the respiratory chain blockers affected glycolysis in platelet homogenate. SNAP (20-100 uM) and SNP (50-200 uM) inhibited oxygen consumption by platelets. The effect of SNP and SNAP on glycolysis and respiration was not reduced by 1H-[1,2,4]oxadiazo- lo-[4,3-a]quinoxalin-1-one, a selective inhibitor of NO-stimulated guanylate cyclase. SNAP (5-100 ,aM) and SNP (10-300 uM) inhibited the activity of platelet cytochrome oxidase and had no effect on NADH:ubiquinone oxidoreductase and succinate dehydrogenase. Blocking of the mitochondrial energy production by antimycin A slightly affected collagen-evoked aggregation and strongly inhibited platelet secretion. The results indicate that: 1) in porcine platelets NO is able to diminish mito- chondrial energy production through the inhibition of cytochrome oxidase, 2) the inhibitory effect of NO on platelet secretion (but not aggregation) can be attributed to the reduction of mitochondrial energy production.

3

Step and ramp induction of myocardial ischemia: comparison of in vivo and in silico results

86%

Salem J. E., Cabrera M. E., Chandler M. P., McElfresh T. A., Huang H., Sterk J. P., Stanley W. C.

Journal of Physiology and Pharmacology

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2004

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tom 55

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nr 3

This study tested the robustness of our computational model of myocardial metabolism by comparing responses to two different inputs with experimental data obtained in pigs under similar conditions. Accordingly, an abrupt and a gradual reduction in coronary flow of similar magnitude were implemented and used as model input. After flow reductions reached 60% from control values, ischemia was kept constant for 60 min in both groups. Our hypotheses were that: (1) these two flow-reduction profiles would result in different transients (concentrations and flux rates) while having similar steady-state values and (2) our model-simulated responses would predict the experimental results in an anesthetized swine model of myocardial ischemia. The two different ischemia-induction patterns resulted in the same decrease in steady-state MVO2 and in similar steady-state values for metabolite concentrations and flux rates at 60 min of ischemia. While both the simulated and experimental results showed decreased glycogen concentration, accumulation of lactate, and net lactate release with ischemia, the onset of glycogen depletion and the switch to lactate efflux were more rapid in the experiments than in the simulations. This study demonstrates the utility of computer models for predicting experimental outcomes in studies of metabolic regulation under physiological and pathological conditions.

4

Gender dimorphism in the exercise-naive murine skeletal muscle proteome

72%

Metskas L. A., Kulp M., Scordilis S. P.

Cellular and Molecular Biology Letters

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2010

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tom 15

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nr 3

507-516

Skeletal muscle is a plastic tissue with known gender dimorphism, especially at the metabolic level. A proteomic comparison of male and female murine biceps brachii was undertaken, resolving an average of 600 protein spots of MW 15–150 kDa and pI 5–8. Twenty-six unique full-length proteins spanning 11 KOG groups demonstrated statistically significant (p<0.05) abundance differences between genders; the majority of these proteins have metabolic functions. Identified glycolytic enzymes demonstrated decreased abundance in females, while abundance differences in identified oxidative phosphorylation enzymes were specific to the proteins rather than to the functional group as a whole. Certain cytoskeletal and stress proteins showed specific expression differences, and all three phosphorylation states of creatine kinase showed significant decreased abundance in females. Expression differences were significant but many were subtle (≤ 2-fold), and known hormonally-regulated proteins were not identified. We conclude that while gender dimorphism is present in non-exercised murine skeletal muscle, the proteome comparison of male and female biceps brachii in exercise-naive mice indicates subtle differences rather than a large or obviously hormonal dimorphism.

5

Lactate in cardiogenic shock - current understanding and clinical implications

72%

Kubiak G. M., Tomasik A. R., Bartus K., Olszanecki R., Ceranowicz P.

Journal of Physiology and Pharmacology

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2018

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tom 69

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nr 1

6

Artykuł dostępny w postaci pełnego tekstu - kliknij by otworzyć plik

Influence of glycolysis process on the formation of meat quality parameters

72%

Wozniak K., Korpal A., Terman A.

Folia Pomeranae Universitatis Technologiae Stetinensis. Agricultura, Alimentaria, Piscaria et Zootechnica

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2017

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tom 42

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nr 2(334)

7

Physiological and biochemical changes associated with cotton fibre development. VII. Carbohydrate metabolism

72%

Thaker V. S., Rabadia V. S., Singh Y. D.

Acta Physiologiae Plantarum

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1999

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tom 21

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nr 1

The relationship between growth and some enzymes of carbohydrate metabolism in developing cotton fibre were studied. Two respiratory pathways of glucose oxidation i.e. oxidative pentose phosphate pathway (OPPP) and glycolysis operates in the elongating cotton fibres and the extent of their operation varies with the demand for respiratory products. In this respect, hexokinase, G-6-PDH, 6PGDH, and MDH show increased activities during the period of rapid cell elongation and decreased activities when rate slows down. The conversion of PEP to malate and/or via a transhydrogenase system consisting of enzymes PEPC, MDH and NADP-MDH(d) may play a significant role in carbohydrate compartmentation of developing cotton fibre. As the rate of fibre growth slows down, a decline in enzyme activities, points to a shift in metabolic priorities.

8

Metabolic responses of Lemna minor to lead ions. I. Growth, chlorophyll level and activity of fermentative enzymes

72%

Garnczarska M., Ratajczak L.

Acta Physiologiae Plantarum

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2000

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tom 22

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nr 4

9

Molecular evolution of enolase

72%

Piast M., Kustrzeba-Wojcicka I., Matusiewicz M., Banas T.

Acta Biochimica Polonica

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2005

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tom 52

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nr 2

Enolase (EC 4.2.1.11) is an enzyme of the glycolytic pathway catalyzing the dehydratation reaction of 2-phosphoglycerate. In vertebrates the enzyme exists in three isoforms: α, β and γ. The amino-acid and nucleotide sequences deposited in the GenBank and SwissProt databases were subjected to analysis using the following bioinformatic programs: ClustalX, GeneDoc, MEGA2 and S.I.F.T. (sort intolerant from tolerant). Phylogenetic trees of enolases created with the use of the MEGA2 program show evolutionary relationships and functional diversity of the three isoforms of enolase in vertebrates. On the basis of calculations and the phylogenetic trees it can be concluded that vertebrate enolase has evolved according to the “birth and death” model of evolution. An analysis of amino acid sequences of enolases: non-neuronal (NNE), neuron specific (NSE) and muscle specific (MSE) using the S.I.F.T. program indicated non-uniform number of possible substitutions. Tolerated substitutions occur most frequently in α-enolase, while the lowest number of substitutions has accumulated in γ-enolase, which may suggest that it is the most recently evolved isoenzyme of enolase in vertebrates.

10

The Crabtree effect: a new look at the old problem

72%

Wojtczak L.

Acta Biochimica Polonica

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1996

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tom 43

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nr 2

Inhibition of respiration by glucose, known as the Crabtree effect, has been observed in several tumours and some other highly glycolytic cells and tissues. Among mechanisms proposed to explain this effect were: competition between glycolysis and respiration for ADP or for inorganic phosphate, change of intracellular pH, change in the permeability of mitochondrial membranes, specific regulatory behaviour of glycolytic enzymes, and specific enzyme topography within the cell. None of these proposals alone seems satisfactory. The present article describes the research carried out in the author's laboratory, pointing to the role of Ca2+ in the mechanism of the Crabtree effect This supposition is based on the following observations: (1) in Ehrlich ascites tumour cells glucose elicits a steady increase of the cytoplasmic concentration of free Ca2+; (2) isolated Ehrlich ascites mitochondria and mitochondria within digitonin-permeabilised cells, preloaded with Ca2+, exhibit a depression of State 3 respiration and lowering of the rate of ATP synthesis; (3) ATPase activity of toluene-permeabilised Ehrlich ascites mitochondria becomes substantially inhibited at micromolar concentrations of Ca2+; (4) Ca2+ potentiates the effect of the inhibitory subunit of F1F0-ATPase. These results allow to hypothesize on the following sequence of events: (1) glucose elevates the cytoplasmic concentration of Ca2+; (2) this elicits an increased accumulation of Ca2+ in mitochondria; (3) loading of mitochondria with Ca2+ leads to an increased association of the inhibitory subunit with F1F0 which results in (4) the inhibition of coupled respiration. The importance of these mechanisms for glycolytic and rapidly proliferating cells is discussed.

11

Histochemical studies on the activity of oxidoreductases during the embryonic development of Toxocara canis

72%

Kolodziejczyk L.

Zoologica Poloniae

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1998

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tom 43

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nr 1-4

12

In vitro evolution and characterization of a copper resistant strains and populations of Chlamydomonas reinhardtii

58%

Plucinski B., Waloszek A., Strzalka K.

BioTechnologia. Journal of Biotechnology Computational Biology and Bionanotechnology

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2013

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tom 94

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nr 3

13

Effects of nitroglycerin on energy metabolism of rat reticulocytes

58%

Maletic S. D., Kostic M. M.

Journal of Physiology and Pharmacology

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1999

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tom 50

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nr 1

14

Pyruvate kinase - a key enzyme of glycolysis in the tissues of selected snails of Poland

51%

Rybska E., Lesicki A.

Folia Malacologica

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1998

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tom 06

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nr 1-4

15

Activation of phosphofructokinase from the fat body of Hyles euphorbiae L. larvae [Insecta: Lepidoptera] by fructose 2,6-bisphosphate

51%

Lesicki A.

Biological Bulletin of Poznań

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1995

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tom 32

16

Acclimation of poplar trees to heavy metals in polluted habitats: I. Carbohydrate metabolism in fine roots of Populus deltoides

44%

Lorenc-Plucinska G., Stobrawa K.

Acta Societatis Botanicorum Poloniae

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2005

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tom 74

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nr 1

Concentrations of total nonstructural carbohydrates (TNC), soluble carbohydrates, starch, sucrose, glucose, fructose, raffinose, galactose, stachyose, mannitol and specific activities of soluble acid (AI) and neutral (NI) invertases, sucrose synthase (SuSy), hexokinase (HK), fructokinase (FK), glyceraldehyde 3-phosphate dehydrogenase (GAPDH) and glucose 6-phosphate dehydrogenase (G6PDH) were analyzed in fine roots of Populus deltoides Bartr. ex Marsh growing at a polluted site (near copper smelters) and a control site (free from heavy pollution). Also chemical properties of the soil from both sites were assessed. In comparison with the control, fine roots from the polluted site contained greater concentrations of TNC, soluble sugars, starch and sucrose but less hexoses, so they had higher values of sucrolysis index (sucrose/hexoses). The activity of AI, NI and SuSy declined insignificantly, while specific activities of HK, FK, GAPDH and G6PDH were significantly inhibited. The results suggest that a long-term heavy metal stress leads to an accumulation of carbohydrates and altering activities of glycolysis and the oxidative pentose phosphate pathway in fine roots.

Ograniczanie wyników

Inhibitory effect of quercetin on glycolysis in blood platelets

Nitric oxide and platelet energy metabolism

Step and ramp induction of myocardial ischemia: comparison of in vivo and in silico results

Gender dimorphism in the exercise-naive murine skeletal muscle proteome

Lactate in cardiogenic shock - current understanding and clinical implications

Influence of glycolysis process on the formation of meat quality parameters

Physiological and biochemical changes associated with cotton fibre development. VII. Carbohydrate metabolism

Metabolic responses of Lemna minor to lead ions. I. Growth, chlorophyll level and activity of fermentative enzymes

Molecular evolution of enolase

The Crabtree effect: a new look at the old problem

Histochemical studies on the activity of oxidoreductases during the embryonic development of Toxocara canis

In vitro evolution and characterization of a copper resistant strains and populations of Chlamydomonas reinhardtii

Effects of nitroglycerin on energy metabolism of rat reticulocytes

Pyruvate kinase - a key enzyme of glycolysis in the tissues of selected snails of Poland

Activation of phosphofructokinase from the fat body of Hyles euphorbiae L. larvae [Insecta: Lepidoptera] by fructose 2,6-bisphosphate

Acclimation of poplar trees to heavy metals in polluted habitats: I. Carbohydrate metabolism in fine roots of Populus deltoides