Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts: Gene/Protein Disease Symptom Drug Enzyme Compound   Target Concepts: Gene/Protein Disease Symptom Drug Enzyme Compound

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Query: EC:1.8.1.4 (diaphorase)
2,754 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The c14CoS/c14CoS mouse has a homozygous deletion of about 1.2 cM on chromosome 7 that includes the albino (c) locus. The untreated 14CoS/14CoS newborn has been reported to exhibit a marked transcriptional activation of the hepatic NAD(P)H:menadione oxidoreductase (Nmo-1; DT diaphorase; quinone reductase; azo dye reductase) gene, as well as elevated UDP glucuronosyl-transferase (UGT1*06) and glutathione transferase (GT1) activities, when compared with the cch/cch wild-type and the cch/c14CoS heterozygote. We show here that the newborn hepatic activities of seven enzymes that play a role in the oxidative stress response--NMO1, UGT1*06, GT1, copper-zinc superoxide dismutase, glutathione peroxidase, glutathione reductase, and glucose-6-phosphate dehydrogenase--are increased 1.5- to 25-fold in 14CoS/14CoS, as compared with ch/ch and ch/14CoS mice. The activities of four additional enzymes having no known association with the oxidative stress response--benzo[a]pyrene hydroxylase (CYP1A1, cytochrome P(1)450), acetanilide 4-hydroxylase (CYP1A2, cytochrome P(3)450), lactate dehydrogenase (LDH), and NADPH-cytochrome c reductase--are not significantly different among the three genotypes. These data suggest that there exists an "oxidative stress" response in the untreated 14CoS/14CoS newborn. We postulate that a chromosome 7 regulatory gene, which we have named Nmo-1n, might encode a trans-acting negative effector of the Nmo-1 gene, and genes corresponding to the other elevated enzymic activities described above. When both copies of Nmo-1n are deleted, as is the case in 14CoS/14CoS mice, a battery of genes involved in oxidative stress is released from negative control and becomes activated--despite the absence of any apparent oxidative insult by foreign chemicals.
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PMID:"Oxidative stress" response in liver of an untreated newborn mouse having a 1.2-centimorgan deletion on chromosome 7. 154 Jan 61

Neutrophil myeloperoxidase, hydrogen peroxide, and chloride constitute a potent antimicrobial system with multiple effects on microbial cytoplasmic membranes. Among these is inhibition of succinate-dependent respiration mediated, principally, through inactivation of succinate dehydrogenase. Succinate-dependent respiration is inhibited at rates that correlate with loss of microbial viability, suggesting that loss of respiration might contribute to the microbicidal event. Because respiration in Escherichia coli can be mediated by dehydrogenases other than succinate dehydrogenase, the effects of the myeloperoxidase system on other membrane dehydrogenases were evaluated by histochemical activity stains of electrophoretically separated membrane proteins. Two bands of succinate dehydrogenase activity proved the most susceptible to inactivation with complete loss of staining activity within 20 min, under the conditions employed. A group with intermediate susceptibility, consisting of lactate, malate, glycerol-3-phosphate, and dihydroorotate dehydrogenases as well as three bands of glucose-6-phosphate dehydrogenase, was almost completely inactivated within 30 min. The relatively resistant group, including the dehydrogenases for glutamate, NADH, and NADPH and the remaining bands of glucose-6-phosphate dehydrogenase, retained substantial amounts of diaphorase activity for up to 60 min of incubation with the myeloperoxidase system. The differential effects of myeloperoxidase on dehydrogenase inactivation could not be correlated with published enzyme contents of flavin or iron-sulfur centers, potential targets of myeloperoxidase-derived oxidants. Despite the relative resistance of NADH dehydrogenase/diaphorase activity to myeloperoxidase-mediated inactivation, electron transport particles prepared from E. coli incubated for 20 min with the myeloperoxidase system lost 55% of their NADH oxidase activity.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Differential inactivation of Escherichia coli membrane dehydrogenases by a myeloperoxidase-mediated antimicrobial system. 169 36

The activity of oxidoreductases in the hippocampal formation of young adult (3-month old) and aged (24-month old) Wistar rats was compared by histochemical methods. A decreased activity of NADH-diaphorase and dehydrogenases involved in the Krebs cycle and glycolysis as well as an increased activity of glucose-6-phosphate dehydrogenase were demonstrated in the hippocampal nerve cells of aged rats. The activity of oxidoreductases in the glial cells of aged rats was increased. Degenerative changes in scattered mitochondria were seen ultrastructurally. No significant differences in the relative volume fraction of mitochondria in the presynaptic axon terminals and dendrites were found between young adult and aged rats.
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PMID:Age-related abnormalities of oxidoreductase activity and mitochondria in rat hippocampal formation. 169 44

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.
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PMID:Enhanced liver metabolism of mutagens and carcinogens in fish living in polluted seawater. 170 59

Haemonchus contortus, incubated in 10 micrograms/ml and 50 micrograms/ml concentrations of Nilzan and albendazole in Tyrode solution were stained for histoenzymatic demonstration of various phosphatases, oxido-reductases and esterases. The intestine showed major alterations after drug treatments. The alkaline phosphatases (AkPase), adenosine triphosphatase (ATPase), glucose-6-phosphatase, succinic dehydrogenase (SDH), glutamate dehydrogenase (GDH), reduced nicotinamide adenine dinucleotide phosphate diaphorase and reduced nicotinamide adenine dinucleotide diaphorase showed a decreased activity in intestine after Nilzan treatment, whereas lactic dehydrogenase (LDH), glucose-6-phosphate dehydrogenase (G-6-PD) and monoamine oxidase resisted increased reaction. The albendazole treatment resulted in altered distribution pattern of the AkPase, ATPase, SDH, and GDH; while LDH, G-6-PD, and non-specific esterases exhibited slightly enhanced activity in the epithelium. The functional significance of these changes has been fully discussed.
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PMID:Effect of Nilzan and albendazole on the absorptive surfaces of Haemonchus contortus (Nematoda)--a histoenzymic study. 196 79

Topical application on rat oral mucosa of the chemical 4-nitroquinoline 1-oxide (4NQO) has been shown to produce squamous cell carcinomas on the posterior tongue and/or the posterior hard palate. 4NQO is broken down in vivo by a diaphorase, 4NQO reductase (E.C.1.6.99.2), to produce an active molecule believed to be responsible for carcinogenesis. It has been shown that there are higher concentrations of 4NQO reductase in oesophageal mucosa compared with elsewhere in the gastrointestinal tract. The purpose of these experiments was to compare the distribution of certain diaphorases in the oral mucosa. Samples of rat tongue and cheek epithelia were homogenized, then ultracentrifuged to provide mixed cytosol and microsome fractions from the epithelial cells. A spectrophotometer was used to measure the variation in absorbance at 340 nm of NADH consumed by reduction of 4NQO by enzymes present in the tissue extracts. A histochemical technique was used to compare the activity of NADH diaphorase, NADP diaphorase and glucose-6-phosphate dehydrogenase at different sites of the oral mucosa. Statistical analysis showed that there were significant (P less than 0.01) differences between the activities of all three enzymes at different sites of the oral mucosa. In each case, a higher activity was found at the sites of high incidence of squamous cell carcinoma. A lower activity was found at sites where carcinomas did not occur.
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PMID:A relationship found between intra-oral sites of 4NQO reductase activity and chemical carcinogenesis. 211 96

The activity of human myocardial enzymes in sudden coronary death (SCD) was quantitatively histochemically examined. The activity of succinate dehydrogenase (SDH), lactate dehydrogenase (LDH), beta-oxybutyrate dehydrogenase (beta-OBDH), alpha-glycerolphosphate dehydrogenase (alpha-GPDH), NAD-diaphorase (NAD-ase), and glucose-6-phosphate dehydrogenase (G-6-PDH) was measured on prompt autopsies (up to 3 hours of death onset). beta-OBDH and LDH showed an increase in activity in the myocardium from the subjects who had suddenly died from coronary heart disease without evident changes in the heart. In SCD in the presence of small cardiosclerosis, the activity of the enzymes characterizing the major processes of energy generation was also enhanced, which was caused by moderately severe myocardial hypertrophy. In the myocardium from the subjects who had died from coronary heart disease in the presence of large postinfarction cardiosclerosis, the activity of the enzymes was directly related to the degree of myocardial hypertrophy and the signs of chronic heart failure. As myocardial hypertrophy progressed, the enzymatic activity rose, but there were signs of chronic heart failure, it fell. The findings suggest that the changes in myocardial enzymatic activity in SCD are heterogeneous and associated with the type of prior abnormalities in the cardiovascular system.
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PMID:[Disorders of myocardial metabolism in sudden coronary death in the presence of coronary atherosclerosis: findings of quantitative histoenzymologic studies]. 221 37

Histochemical profiles were made of identified spinal motoneurons from normal adult zebrafish and from animals subjected to cordotomy or unilateral axotomy of the motor nerves. The lesions caused an increase of the myotomal area with oxidative muscle fibers. We studied the question: do changes in the myotomal muscle configuration concur with changes in the enzyme histochemical profiles of innervating motoneurons? Based on the location and size of cell somata, two categories of motoneurons are distinguished: large white (W) motoneurons that innervate the deep fast, glycolytic muscle fibers, and smaller red and intermediate (RI) motoneurons that innervate the superficial slow oxidative and intermediate muscle fibers. In normal animals, glucose-6-phosphate dehydrogenase activity is high in the large W motoneurons and relatively low in the small RI motoneurons. The reverse holds for succinate dehydrogenase activity is high in the large W motoneurons and relatively low in the small RI motoneurons. The reverse holds for succinate dehydrogenase activity. W and RI motoneurons show similar nicotinamide adenine dinucleotide diaphorase activity. Short- (2 weeks) and long- (8 weeks) term effects of lesions were studied. The results show that: (1) the 3 types of lesions lead to prolonged changes in the enzyme histochemical profiles of spinal motoneurons. The type of change depends on the type of lesion and on the type of motoneuron; (2) unilateral axotomy of the motor nerves affects the histochemical characteristics of spinal motoneurons and the myotomal muscle fiber type configuration on the ipsi- and contralateral side. The contralateral effects are conceived as adaptations to maintain a left-right symmetry in the motor output.
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PMID:Enzyme histochemical profiles of fish spinal motoneurons after cordotomy and axotomy of motor nerves. 228 25

Quantitative cytochemical techniques have been employed in a study of some of the acute effects of low doses (0.01----1 mU/liter) of TSH on the metabolism of guinea pig thyroid segments maintained in nonproliferative organ culture. The enzymes involved in the synthesis of NADP+ (NAD+ kinase), its reduction by the pentose-shunt (glucose 6-phosphate dehydrogenase), and its reoxidation both by the microsomal electron chain (diaphorase activity) and by participation in other cellular processes, have been examined. The effect of TSH on peroxidase activity has also been studied. After 10 min stimulation with TSH (1 mU/liter) there was a 60% increase in NAD+ kinase activity which preceded changes in the microsomal reoxidation of NADPH (up 33% by 30 min). There were no changes in the activity of glucose 6-phosphate dehydrogenase. There was a sustained rise in peroxidase activity which reached 129% over control after 30 min. This is the first in vitro demonstration of an acute stimulation of peroxidase and kinase activities by physiological concentrations of TSH. NADPH reoxidation after stimulation with TSH was such that the ratio of NADPH reoxidized via the microsomal respiratory pathway (diaphorase, hydrogen pathway 1) relative to that available for cytosolic utilization (hydrogen pathway 2) increased compared to the unstimulated controls. We suggest that increased NADP+ production (via NAD+ kinase activity) and the preferential shuttling of the NADPH for reoxidation via the microsomal respiratory pathway, coupled with greatly stimulated peroxidase activity, may be important regulators of the control of thyroglobulin iodination and hence thyroid hormone production.
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PMID:Acute stimulation of thyroidal NAD+ kinase, NADPH reoxidation, and peroxidase activities by physiological concentrations of thyroid stimulating hormone acting in vitro: a quantitative cytochemical study. 284 14

F344 Male rats weighting between 90 and 110 gm were given 90 ppm diethylnitrosamine in their drinking water for 5 weeks. Seven weeks after the administration of carcinogen was completed, the rats were sacrificed and sections of their livers were embedded in methacrylate. Serial sections 2 or 4 micron in thickness demonstrated the presence of gamma-glutamyl transpeptidase, acid phosphatase, adenosine triphosphatase, aldehyde dehydrogenase, alkaline phosphatase, alpha-naphthyl butyrate esterase, DT diaphorase, glucose-6-phosphate dehydrogenase, and 5'-nucleotidase activity and glycogen. The use of 4-micron sections of methacrylate-embedded tissue allows the evaluation of many more phenotypic markers in serial sections than is currently possible with frozen sections.
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PMID:Examination of enzyme-altered foci with gamma-glutamyl transpeptidase, aldehyde dehydrogenase, glucose-6-phosphate dehydrogenase, and other markers in methacrylate-embedded liver. 287 68


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