Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UNIPROT:Q8NEX9 (reductase)
 26,410 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Perfusion of rat livers with 10 mM-fructose or pretreatment of the rat with 6-aminonicotinamide (70 mg/kg) 6 h before perfusion decreased intracellular ATP concentrations and increased the rate of p-nitroanisole O-demethylation. This increase was accompanied by a decrease in the free [NADP+]/[NADPH] ratio calculated from concentrations of substrates assumed to be in near-equilibrium with isocitrate dehydrogenase. After pretreatment with 6-aminonicotinamide the [NADP+]/[NADPH] ratio also declined. Reduction of NADP+ during mixed-function oxidation may be explained by inhibition of of one or more NADPH-generating enzymes. Glucose 6-phosphate dehydrogenase, 6-phosphogluconate dehydrogenase, isocitrate dehydrogenase and "malic" enzyme, partially purified from livers of phenobarbital-treated rats, were inhibited by ATP and ADP. Inhibitor constants of ATP for the four dehydrogenases varied considerably, ranging from 9 micrometer for "malic" enzyme to 1.85 mM for glucose 6-phosphate dehydrogenase. NADPH-cytochrome c reductase was also inhibited by ATP (Ki 2.8 mM) and by ADP (Ki 0.9 mM), but not by AMP. Concentrations of ATP and ADP that inhibited glucose 6-phosphate dehydrogenase and the reductase were comparable with concentrations in the intact liver. Thus agents that lower intracellular ATP may accelerate rates of mixed-function oxidation by a concerted mechanism involving deinhibition of NADPH-cytochrome c reductase and one or more NADPH-generating enzymes.
 ...
PMID:Regulation of p-nitroanisole O-demethylation in perfused rat liver. Adenine nucleotide inhibition of NADP+-dependent dehydrogenases and NADPH-cytochrome c reductase. 4 95

The activity of enzymes regulating the processes providing functional activity of leukocytes was studied in the exudate leukocytes of healthy rabbits and animals with alloxan diabetes. Rabbits with diabetes displayed a reduction of hexokinase, phosphoglucomutase, glucose-6-phosphate dehydrogenase and adenylate kinase activity. The activity of UDPH-pyrophosphorylase, UDPH-glycogentranspherase, 6-phosphogluconate dehydrogenase and glutathion reductase showed no significant changes in the exudate leukocytes in diabetes. A reduction of hexokinase and glucose-6-phosphate dehydrogenase limiting glycolysis and the pentose-phosphate cycle, respectively, providing energy for leukocytes and important in protein metabolism of these cells, is of great significance in the reduction of functional activity of leukocytes in the inflammatory focus in diabetes.
 ...
PMID:[Enzymatic profile of the exudate leukocytes in diabetes mellitus]. 9 55

The effect of iron deficiency on a number or iron containing enzymes in rat liver has been examined. In addition, 6-phosphogluconate dehydrogenase and glucose 6-phosphate dehydrogenase have been assayed. Of the mitochondrial electron transport reactions only succinate-cytochrome C reductase activity was decreased in iron deficient animals. Microsomal reductase enzymes associated with the NADPH-oxidase system were also markedly decreased although cytochrome P450 concentrations were unaffected. Both 6-phosphogluconate dehydrogenase and glucose 6-phosphate dehydrogenase were reduced in young iron deficient rats but the former had returned to control levels at the age of 14 weeks.
 ...
PMID:The effects of iron deficiency on rat liver enzymes. 17 99

In leukocytes of exudate from diabetic rabbits, the activities of hexokinase, phosphoglucomutase and glucose-6-phosphate dehydrogenase are increased, and a tendency of adenylate kinase activity to decline is observable. The activities of UDP-pyrophosphatase, UDP-glycogentransferase, 6-phosphogluconate dehydrogenase and glutahione reductase in the exudate erythrocytes in diabetes are not essentially altered. The decrease of the key enzymes of glycolysis and pentose phosphate cycle, providing the leukocytes with energy and metabolites, reduces the functional activity of leukocytes from exudate in diabetes.
 ...
PMID:[Enzyme profile of exudate leukocytes from diabetic rabbits]. 51 96

In extracts of rabbit bone marrow cells was studied effect of erythropoietine on the activity of some enzymes (hexokinase, phosphoglucomutase, phosphohexoisomerase, lactate dehydrogenase, glucoso-6-phosphate dehydrogenase, 6-phosphogluconate dehydrogenase and NADP-reductase). The NADP-reductase activity was increased under the effect of erythropoietine; the activities of other enzymes studied was not altered.
 ...
PMID:[Study of the mechanism of erythropoietin effect on energy metabolism in the bone marrow]. 103 Aug 78

The concentration of 2,3-diphosphoglycerate, and the activities of the enzymes hexokinase, glucose-6-phosphate dehydrogenase, 6-phosphogluconate dehydrogenase, glutathione reductase and NADH-dependent methaemoglobin reductase in the erythrocytes of newborn and adult sheep were investigated. All the enzyme activities and the concentration of 2,3-diaphosphoglycerate were found to be significantly greater in the erythrocytes of newborn lambs than in those of adult sheep.
 ...
PMID:Postnatal changes in the levels of 2,3-diaphosphoglycerate, reduced glutathione and some enzyme activities in the erythrocytes of lambs. 126 64

Specimens of the seawater fish annular seabream (Diplodus annularis) were caught from a polluted harbor area and from a clean reference area. Seawater concentrates and fish-muscle extracts were not mutagenic in the Salmonella reversion test. Liver preparations of fish from the 2 sources were comparatively assayed for microsomal mixed-function oxidases and cytosolic biochemical parameters, as well as for the ability of S12 fractions to activate promutagens or to detoxify direct-acting mutagens. A shift of the cytochrome P-450 peak from 450.3 to 448.5 was accompanied by a 4.5-fold increase in arylhydrocarbon hydroxylase activity in fish living in the polluted environment. At the same time, glucose 6-phosphate dehydrogenase and 6-phosphogluconate dehydrogenase were doubled in the cytosol of the same animals, while reduced glutathione (GSH) peroxidase and GSH S-transferase were slightly yet significantly depressed. No significant difference was recorded for other biochemical parameters, including GSH, oxidized glutathione (GSSG) reductase, NADH- and NADPH-dependent diaphorases, and DT diaphorase. In parallel, fish exposed to polluted seawater exhibited a significant and marked enhancement of the metabolic activation of the pyrolysis product Trp-P-2 and of benzo[a]pyrene-trans-7,8-diol, and at the same time were less efficient in detoxifying the antitumor compound ICR 191. Liver S12 fractions from both sources efficiently decreased the direct mutagenicity of sodium dichromate, and failed to activate benzo[a]pyrene and aflatoxin B1 to mutagenic metabolites. These results provide evidence that both biochemical parameters and the overall capacity of fish liver to activate or detoxify certain mutagens can be assumed to be sensitive indicators of exposure to mixed organic pollutants in the marine environment.
 ...
PMID:Enhanced liver metabolism of mutagens and carcinogens in fish living in polluted seawater. 170 59

We aim to evaluate the effects of phenobarbital (PB) on the liver drug metabolism, NADPH production capacity and terminal gluconeogenic enzyme, glucose-6-phosphatase (G6Pase) activity in the diabetic state associated with genetic obesity in mice. The results showed that PB treatment increased the amount of liver total cytochrome P450 (cytP450), a drug metabolizing monooxygenase enzyme in genetically obese, hyperglycemic (ob/ob) mice 6-fold and the total activities of other monooxygenase enzymes NADPH cytP450 reductase and 7-ethoxyresorufin O-deethylase (ERDE) 2- and 6.5-fold, respectively. In addition, the regimen increased the liver total activities of two NADPH generating enzymes, 6-phosphogluconate dehydrogenase (6PGDH) and malic enzyme (ME) in obese mice suggesting that the regimen enhanced liver NADPH production capacity in the animals. The data further showed that PB treatment decreased the high hepatic G6Pase activity in obese mice. Both enhanced NADPH generating enzyme activities and lowered G6Pase activity may suppress hepatic glucose output. Since NADPH is required for drug oxidation reactions as a reducing cofactor, high NADPH generating capacity may facilitate liver drug metabolism in vivo. Although the diabetic state in obese mice differs somewhat from that seen in non-insulin dependent diabetic subjects (NIDDs), these findings provide some knowledge about the possible biochemical mechanisms whereby PB treatment normalizes drug metabolism and glycemic control in NIDDs, as has been noted in previous studies.
 ...
PMID:Hepatic drug metabolism and the activities of NADPH generating enzymes and glucose-6-phosphatase in phenobarbital treated genetically obese (ob/ob) mice. 283 24

Regional distributions of thiobarbituric acid-reactive products, activities of enzymes regulating metabolism of oxygen free radicals, and some of the related enzymes were studied in 10 areas of adult and aged rat brains. Thiobarbituric acid-reactive products were lower in cerebral cortex, septal area, hippocampus, caudate-putamen, and substantia nigra compared with other areas studied in adult rats; however, they increased significantly in the former areas with aging. A slight but significant reduction in superoxide dismutase activity was noted in frontal cortex, septal area, caudate-putamen, and substantia nigra with aging. Glutathione peroxidase and reductase activities were highest in caudate-putamen and in substantia nigra. Glucose-6-phosphate dehydrogenase and 6-phosphogluconate dehydrogenase activities were lowest in cortical areas. Phosphofructokinase activity was lowest in septal area and hippocampus in aged rats. Glyceraldehyde-3-phosphate dehydrogenase activity showed only small regional and evolutional changes. Lactate dehydrogenase activity declined with age in most of the areas studied. sn-Glycerol-3-phosphate dehydrogenase activity showed small changes with aging except in hippocampus, where 40% reduction was noted. Generally, cerebral cortical areas, hippocampus, and septal areas were not particularly enriched in enzymes regulating the metabolism of oxygen free radicals. The results were discussed in relation to the role of free radicals in aging.
 ...
PMID:Regional distributions of thiobarbituric acid-reactive products, activities of enzymes regulating the metabolism of oxygen free radicals, and some of the related enzymes in adult and aged rat brains. 293 81

N-acetylcysteine (NAC) was administered to rats in various combinations with an enzyme inducer (Aroclor 1254) and with depletors of reduced glutathione (GSH), i.e., diethyl maleate (DEM) and buthionine sulfoximine (BSO). NAC increased intracellular glutathione levels in erythrocytes and in liver and lung cells, and replenished its stores following depletion. It did not affect the concentrations nor the spectral properties of cytochromes P-450 in hepatic and pulmonary microsomes, whereas it stimulated, especially in Aroclor-pre-treated animals, cytosolic enzyme activities involved in NADP reduction (glucose 6-phosphate dehydrogenase and 6-phosphogluconate dehydrogenase), in glutathione reduction (GSSG-reductase) and in the reductive detoxication of xenobiotics by-passing formation of reactive oxygen species (DT-diaphorase). In vivo treatment with the drug enhanced detoxication by liver and lung S-12 fractions of direct-acting mutagens (ICR 191, epichlorohydrin, 4-nitroquinolino-N-oxide and dichromate) and counteracted opposite effects triggered by administration of GSH depletors. The metabolic activation of procarcinogens (aflatoxin B1, 2-aminofluorene, cyclophosphamide, benzo[a]pyrene, a tryptophan pyrolysate product and cigarette smoke condensate) was inhibited by NAC in uninduced rats, while it was further stimulated in Aroclor-pre-treated animals. Additional assays, performed also with other enzyme inducers (phenobarbital and 3-methylcholanthrene) suggested that the effect of NAC on the metabolic activation of procarcinogens depends on the balance between an increased production of mutagenic metabolites (prevailing in induced animals) and their binding by intracellular thiols (prevailing under normal conditions). Thus, due to its dual role as a nucleophile and as a SH donor, NAC appears to exert protective effects by modulating glutathione metabolism and the biotransformation of mutagenic/carcinogenic compounds. This may have clinical relevance, since NAC is administered to individuals, such as cigarette smokers, who are more heavily exposed to GSH depletors and to carcinogenic agents.
 ...
PMID:In vivo effects of N-acetylcysteine on glutathione metabolism and on the biotransformation of carcinogenic and/or mutagenic compounds. 390 42


1 2 3 Next >>