Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:1.6.99.3 (diaphorase)
5,903 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Thirty-six wild-caught woodchucks (Marmota monax) were characterized according to sex, weight, trapping locality, liver pathology, and serum or hepatic markers of woodchuck hepatitis virus. Liver subcellular fractions were assayed for microsomal cytochromes P-450, aryl hydrocarbon hydroxylase, glutathione, cytosolic enzymes involved in its metabolism (glutathione S-transferase, glutathione peroxidase, and glutathione reductase), in the hexose monophosphate shunt (glucose 6-phosphate dehydrogenase and 6-phosphogluconate dehydrogenase), NADH- and NADPH-dependent diaphorases, and DT diaphorase. Moreover, liver postmitochondrial fractions were assayed for their ability to activate procarcinogens [i.e., a tryptophan pyrolysate product, aflatoxin B1, 2-aminofluorene, and trans-7,8-dihydrobenzo(a)pyrene] to mutagenic metabolites in the Ames reversion test and to decrease the activity of direct-acting mutagens [i.e., 4-nitroquinoline N-oxide, 2-methoxy-6-chloro-9-[3-(2-chloroethyl)aminopropylamino]acridine X 2HCl, and sodium dichromate]. A considerable interindividual variability in metabolism was observed among the examined woodchucks. Some of the investigated parameters were more elevated in virus carriers, especially in those suffering from chronic active hepatitis, but only a few of the recorded differences (i.e., oxidized glutathione reductase and NADPH-dependent diaphorase) were statistically significant. The comparison of the monitored activities in woodchucks and in other rodent species (rat and mouse) led to the conclusion that the liver metabolism of mutagens and carcinogens in woodchucks is more oriented in the sense of activation, while detoxification mechanisms are more efficient in rats and mice.
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PMID:Metabolism of mutagens and carcinogens in woodchuck liver and its relationship with hepatitis virus infection. 360 50

The individual effects of two putative metabolites of primaquine (5,6-dihydroxyprimaquine and 5,6-dihydroxy-8-aminoquinoline) on the hexose monophosphate shunt (HMS) and on the ATP-dependent proteolytic system which rapidly degrades oxidized erythrocyte protein were measured in intact red blood cells in vitro from two blood donors. In red cells treated with nitrite (1-40 mM) or phenylhydrazine (0.01-10 mM), proteolytic activity was detected only with concentrations (7.5 mM NaNO2 and 0.25 mM phenylhydrazine) causing greater than 15-fold elevation of HMS activity, and glucose-6-phosphate dehydrogenase (G6PD)-deficient (25% of normal activity) red cell suspensions thus treated showed approximately 30% greater proteolysis. G6PD-normal and deficient red cells treated with the primaquine analogs, however, did not experience proteolysis with concentrations (0.25 mM) in excess of those causing 17-fold elevation of HMS activity. Stimulation of the HMS by the primaquine analogs thus appears unrelated to an erythrotoxic oxidative stress. Methylene blue is known to cause an elevation of HMS activity through direct and diaphorase II-dependent oxidation of reduced nicotinamide adenine dinucleotide phosphate (NADPH) which is independent of injurious oxidative stress. It was found that the putative primaquine metabolites also caused direct and diaphorase II-dependent oxidation of NADPH in dilute hemolysate, thus suggesting that the putative primaquine metabolites have a methylene blue-like redox disposition in red blood cells. Results obtained in this study suggest that the hemolytic toxicity of primaquine may be unrelated to processes which lead to oxidative deterioration of red cell protein.
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PMID:Oxidative activity of hydroxylated primaquine analogs. Non-toxicity to glucose-6-phosphate dehydrogenase-deficient human red blood cells in vitro. 375 45

The biologic basis for the elevated histochemical reduction of nitroblue tetrazolium dye (NBT) in neutrophils from patients with acute bacterial infection or polycythemia vera was studied. A precipitin reaction followed mixing NBT with heparin. NBT was reduced after phagocytosis of this complex (H-NBT) by polymorphonuclear leukocytes (PMNs). Ingestion required divalent cations and was facilitated by the presence of complement. H-NBT incubated with normal but not with C2-deficient human serum converted native C3 to its inactive form. Phagocytic indices were determined in patients and controls by measuring O(2) utilization and hexose monophosphate shunt activity and by visually counting cell-associated latex particles. Significant elevations above controls were observed in phagocytes isolated from all patients with elevated histochemical NBT scores when H-NBT complex, latex, or zymosan was employed as the phagocytic particle. Increased indices were observed in the presence of fresh AB serum, heat-inactivated AB serum, or without serum. Serum from patients with elevated NBT scores did not alter phagocytosis in control phagocytes. With NADH and NADPH as substrates, total NBT diaphorase activity of sonicated leukocytes was normal in all patients. These results suggest that increased phagocytic capacity of PMNs is the primary cause of increased histochemical NBT reduction. The PMNs of patients with acute bacterial infection or polycythemia vera may have alterations in their cell membranes which lead to an enhanced rate of phagocytosis.
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PMID:Enhanced phagocytic capacity. The biologic basis for the elevated histochemical nitroblue tetrazolium reaction. 415 97

Evidence that the bactericidal ability and the stimulated oxidative metabolism of leukocytes appear in parallel during fetal development of the Minnesota Miniature pig has been obtained by application of the techniques applied to studies of human cells. It was demonstrated that leukocytes from 87- to 90-day fetuses were fully capable of ingesting Staphylococcus aureus but greatly diminished in bactericidal capacity as compared to leukocytes of older fetuses and adults. Although resting levels of oxygen consumption and hexose monophosphate pathway activity of leukocytes from the younger fetuses compared well with those of leukocytes from older animals, the phagocytosis-stimulated increments of metabolism were much less at 87 to 90 days of gestation than at later developmental stages. Both bactericidal capacity and increased metabolism of leukocytes reach adult levels by 100 days of gestation (normal gestation period of 115 to 120 days). Acrylamide gels stained for reduced nicotinamide adenine dinucleotide (NADH) and NADH phosphate (NADPH) diaphorase activity after disc electrophoresis of leukocyte extracts revealed normal mobility and intensity of NADH diaphorase bands. Three NADPH diaphorase bands were present in adult leukocyte extracts. Only the fast-migrating NADPH diaphorase band of 87- to 90-day cells stained with decreased intensity. This "deficiency" was no longer present at the later fetal period. The fast-migrating NADPH diaphorase band may represent an electron transfer protein which functions in cyanide-insensitive respiration of the leukocytes of the pig.
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PMID:Development of bactericidal capacity and phagocytosis-associated metabolism of fetal pig leukocytes. 463

Quantitative cytochemical investigations have detected individual variations between murine peritoneal macrophages and have shown distinct difference between resident and exudate populations. The latter generally contain greater amounts of protein, RNA, acid phosphatase, succinate dehydrogenase, lactate dehydrogenase, glucose-6-phosphate dehydrogenase, and NADH dehydrogenase. On te other hand, no differences were detected in the cellular content of DNA, not-specific esterase, and NADPH dehydrogenase. In many instances they reflect the biochemical findings of other investigators including the stimulation of glycolysis, tricarboxylic acid cycle and hexose monophosphate shunt pathways, which can occur in elicited or activated macrophages. Although cytochemical differences between the two populations exist, it cannot be stated whether they represent distinct cell lines or different functional states of the same cell population.
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PMID:A quantitative cytochemical analysis of resident and exudate macrophages. 616 17

A histochemical study of the metabolism of rat renal arteries and arterioles. Rat renal arteries and arterioles were examined histochemically to determine their metabolic profiles. Succinate, malate and NAD-isocitrate dehydrogenase, cytochrome oxidase and ubiquinone were assessed to determine aerobic metabolism. Glucose-6-phosphate dehydrogenase and DPN diaphorase were evaluated to determine hexose-monophosphate-shunt activity. Anaerobic metabolism was evaluated via lactate dehydrogenase, and the substrate, glycogen. Gomori's lipase, beta-hydroxybutyrate dehydrogenase and amounts of neutral fat and free fatty acids were assessed as indicators of lipid utilization. Myosin ATPase activity was evaluated as an index of ATP utilization for contraction. Deoxyribonucleic and ribonucleic acids were appraised as indicators of protein synthesis. In general, the oxidative enzymes and myosin ATPase demonstrate considerable activity in renal arteries and arterioles which suggests aerobic metabolism and ATP usage. Renal arteries and arterioles also appear capable of anaerobic metabolism as indicated by strong lactate dehydrogenase reactivity and by the presence of slight to moderate quantities of glycogen, while high levels of glucose-6-phosphate dehydrogenase and moderate amounts of deoxyribonucleic acid suggest a potential for beta-hydroxybutyrate dehydrogenase, minimal lipase activity, and the absence of fatty acids with substantial amounts of neutral fat, indicate limited lipid catabolism.
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PMID:A histochemical study of the metabolism of rat renal arteries and arterioles. 620 11

The energy metabolism of the English E-CMO strain of contagious equine metritis bacterium was studied in whole cells and cell extracts. This bacterium appears to have an active Krebs cycle and probably obtains energy by oxidative phosphorylation since glycolysis and the hexose monophosphate pathways appear to be absent. These conclusions are based on the findings that [U-14C]glucose incorporation by this bacterium is below the level of detection, and that respiration is stimulated by Krebs cycle intermediates (i.e., malate, citrate, and succinate), but not by glucose, fructose, maltose, or sucrose. Furthermore, support comes from the fact that enzymes generally associated with the Krebs cycle and electron transport (i.e., malate dehydrogenase, succinate dehydrogenase, isocitrate dehydrogenase, fumarate hydratase, malate dehydrogenase [decarboxylating], cytochrome oxidase, superoxide dismutase, NADH dehydrogenase, and catalase) were detected. Those enzymes normally associated with glycolysis and the hexose monophosphate pathways (i.e., hexokinase, glucose 6-phosphate dehydrogenase, fructose biphosphate aldolase, glycerol 3-phosphate dehydrogenase, phosphoenolpyruvate carboxykinase, pyruvate kinase, phosphate acetyl transferase, acetate kinase, alcohol dehydrogenase, and lactate dehydrogenase) were below the level of detection.
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PMID:Energy metabolism of the contagious equine metritis bacterium. 708 71

Lead, zinc and copper were administered i.p singly or in combination as acetate salts to rats for 14 consecutive days. It was observed that lead induced drastic changes, copper induced moderate changes but zinc did not cause any significant change in the cholesterol and phospholipid content, hexose, hexosamine and sialic acid levels and activities of the erythrocyte membrane enzymes--acetylcholinesterase (AChE), NADH dehydrogenase and Na(+)-K+ ATPase. In the combined metal treatment the presence of zinc considerably reduced the changes induced by lead and copper.
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PMID:Metal induced changes in the erythrocyte membrane of rats. 761 77

The rate of transfer of reducing equivalents from cytoplasm to mitochondria has been examined in Ehrlich ascites tumour cells incubated in the presence of lactate. The flux of reducing equivalents was determined from the rate of metabolism of reduced intermediates that are oxidized within the cytosol. The magnitude of the flux of reducing equivalents was dependent on both the concentration of added lactate and the presence of carbohydrate. The rate of flux was twice as great in the presence of glucose and four times as high when glucose and lactate were added together as when lactate was the only added substrate. Fructose was less effective than glucose in stimulating reducing equivalent flux. In the presence of glucose or fructose, there was a substantial accumulation of hexose phosphates, dihydroxyacetone phosphate and glycerol 3-phosphate. Rotenone, an inhibitor of NADH dehydrogenase, and amino-oxyacetate, which inhibits the malate/aspartate shuttle, were powerful suppressors of reducing equivalent flux from lactate as sole substrate, but were much less potent in the presence of carbohydrate. Antimycin substantially inhibited reducing equivalent flux from all combinations of added substrates, consistent with its ability to block oxidation of reducing equivalents transferred by both the malate/aspartate and glycerol 3-phosphate shuttles. The glycerol 3-phosphate shuttle represents around 80% of the maximum total observed activity but is active only while glycolytic intermediates are present to provide the necessary substrates of the shuttle. This Ehrlich ascites cell line has an essentially similar total reducing equivalent shuttle capacity to that of isolated hepatocytes.
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PMID:Substrate-dependent utilization of the glycerol 3-phosphate or malate/aspartate redox shuttles by Ehrlich ascites cells. 765 9

Glucose metabolism of bifidobacteria in the presence of 2-amino-3-carboxy-1,4-naphthoquinone (ACNQ), a specific growth stimulator for bifidobacteria, and ferricyanide (Fe(CN)(6)(3-)) as an extracellular electron acceptor was examined using resting cells of Bifidobacterium longum and Bifidobacterium breve. NAD(P)H in the cells is oxidized by ACNQ with the aid of diaphorase activity, and reduced ACNQ donates the electron to Fe(CN)(6)(3-). Exogenous oxidation of NADH by the ACNQ/Fe(CN)(6)(3-) system suppresses the endogenous lactate dehydrogenase reaction competitively, which results in the remarkable generation of pyruvate and a decrease in lactate production. In addition, a decrease in acetate generation is also observed in the presence of ACNQ and Fe(CN)(6)(3-). This phenomenon could not be explained in terms of the fructose-6-phosphate phosphoketolase pathway, but suggests rather that glucose is partially metabolized via the hexose monophosphate pathway. This was verified by NADP(+)-induced reduction of Fe(CN)(6)(3-) in cell-free extracts in the presence of ACNQ. Effects of the ACNQ/Fe(CN)(6)(3-) system on anaerobically harvested cells were also examined. Stoichiometric analysis of the metabolites from the pyruvate-formate lyase pathway suggests that exogenous oxidation of NADH is an efficient method to produce ATP in this pathway.
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PMID:2-Amino-3-carboxy-1,4-naphthoquinone affects the end-product profile of bifidobacteria through the mediated oxidation of NAD(P)H. 1207 35


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