Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:P04179 (MnSOD)
 2,777 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Three superoxide dismutase isoenzymes of different cellular location were detected in an homogenate of Trichuris ovis. Each of these molecular forms was purified by differential centrifugation and precipitation with ammonium sulphate, followed by chromatography on DEAE-cellulose and Sephadex G-75 columns. The activity levels of the two molecular forms detected in the mitochondrial (one cyanide sensitive Cu-Zn-SOD and the other cyanide insensitive Mn-SOD) were higher than that of the superoxide dismutase detected in the cytoplasmic fraction (cyanide sensitive Cu-Zn-SOD). All molecular forms present evident differences to the SODs contained in the host liver. Molecular mass and some of the physical and chemical properties of the enzyme was determined for all three molecular forms. An inhibitory effect on the SOD of the parasite an the host was detected with a series of compounds, some of which markedly inhibited parasite enzyme but not host enzyme.
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PMID:Superoxide dismutase from Trichuris ovis--inhibition by benzimidazoles and pyrimidine derivatives. 134 92

Eucaryotes have two major forms of superoxide dismutase (SOD), Cu,ZnSOD and MnSOD; in most tissues Cu,ZnSOD is present in higher amounts than MnSOD. To assay MnSOD, Cu,ZnSOD can be inhibited selectively by millimolar concentrations of cyanide ion. However, calculation of MnSOD activity from the differential cyanide inhibition assay is complex and small experimental errors can cause large errors in the calculated MnSOD activity. We have assessed how interaction of cyanide and hydrogen peroxide with cytochrome c can lead to further errors in the xanthine oxidase-cytochrome c assay for SOD. Alternatively, Cu,ZnSOD can be completely inactivated by 50 mM diethyldithiocarbamate (DDC) at 30 degrees C for 1 h without affecting the activity of MnSOD. Since DDC reduces cytochrome c, the treated samples must be thoroughly dialyzed or desalted before assay. In the case of lung homogenates, dialysis is not an extra step since fresh, untreated samples must also be dialyzed or desalted before assaying by the cytochrome c method. Cu,ZnSOD activity is equal to the activity in the untreated sample minus the activity in the DDC-treated portion of the sample. Another copper chelator, triethylenetetramine, did not inactivate Cu,ZnSOD and could not be used instead of DDC. For accurate measurement of both enzymes in samples where MnSOD contributes only a small fraction of the total SOD activity, the DDC method has the advantage that it provides a direct measure of the MnSOD activity without interference by Cu,ZnSOD.
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PMID:Use of cyanide and diethyldithiocarbamate in the assay of superoxide dismutases. 164 52

A method for copper- and manganese-containing superoxide dismutase (Cu- and MnSOD) assay in tissue homogenates such as liver and brain, based on the measurement of the longitudinal nuclear relaxation time (T1) of F-, has been developed as a preliminary approach to in vivo measurement of these enzymes. The relaxation rate of F-, which increases linearly with the SOD concentration, also depends on the oxidation state of the metal ion present in the active site of the enzyme. The relaxivity values of the oxidized, reduced and turnovering CuSOD were found to be 9.6 x 10(6), much less than 1 x 10(2) and 5.2 x 10(6) M-1 s-1, respectively, while for MnSOD the corresponding values were 2.9 x 10(6), 4.2 x 10(6) and 3.6 x 10(6) M-1 s-1, respectively. These high relaxivity values allow the detection of SODs in brain and liver homogenates where, under aerobic conditions, these enzymes appear in the steady-state. The contribution of the two types of SOD to the F- relaxation rate in the homogenates was measured by addition of either diethyldithiocarbamate or cyanide, both of which selectively inhibit the CuSOD. The comparison between NMR and activity data confirmed the possibility of carrying out accurate and precise measurements of SODs in homogenates by NMR.
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PMID:NMR method for superoxide dismutase assay in brain and liver homogenates. 164 13

The antioxidant defenses of the liver, erythrocytes, blood plasma, and interscapular brown adipose tissue (IBAT) of male ground squirrels were compared with those of male rats kept under identical conditions and fed the same diet. Superoxide dismutase (SOD), ascorbate, vitamin E, catalase, glutathione, and enzymes of glutathione metabolism were measured. In general, antioxidant defenses in erythrocytes were lower in ground squirrels than in rats. The same was true in liver, except that catalase-specific activity was higher. In IBAT, ascorbate, vitamin E, catalase, and glutathione reductase were higher than in rat and more of the SOD activity present was cyanide-insensitive (MnSOD). It is suggested that IBAT in ground squirrels may need a relatively greater antioxidant defense because of its important role in thermogenesis, especially in reawakening from hibernation. No major differences in antioxidant defenses between male and female ground squirrels were observed, except that the SOD activity of IBAT was higher in females.
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PMID:Antioxidant defenses in the ground squirrel Citellus citellus. 1. A comparison with the rat. 229 34

Lipid peroxide and SOD were selected as free radical related substances and system for their elimination, and detection was evaluated. NADPH-Cytochrome c reductase-Neotetrazolium (NT) method (Mic-NT method) and Xanthine oxidase-Nitrotetrazolium Blue method (XOD-NTB method) are current detection methods of SOD activities. They are based on the O2-specific reaction. Minimum detectable amount of SOD by the Mic-NT method and XOD-NTB method was about 15 ng and 200 ng, respectively. On the other hand, an XOD-NH2OH method which detects SOD activities based on the O2-specific oxidation reaction showed the minimum detectable amount of 2.5 ng. Consequently, SOD-detecting sensitivity of these methods was found to be in the following order: XOD-NH2OH method greater than Mic-NT method greater than XOD-NTB method. In addition, albumin caused a positive error in all three methods. With a monoclonal antibody-aided SOD-analyzing method (EIA method), the minimum detectable amount of SOD was 0.2 ng. The isoenzymes of SOD (Cu, Zn-SOD and Mn-SOD) could be detected separately by 1. deactivating Cu, Zn-SOD with CN- or H2O2 and regarding the remaining activity as Mn-SOD and 2. by deactivating Mn-SOD selectively through pretreatment of the sample with SDS and regarding the remaining activity as Cu, Zn-SOD. TBA method (Yagi's method) has been used frequently for the measurement of serum lipid peroxide.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:[Detection methods of free radical related substances and the system for their elimination]. 260 53

Heat shock proteins are induced at normal temperatures by oxidants and during reoxygenation following hypoxia. We now report cyanide-resistant O2 consumption increased 30-50% in rat lungs exposed to heat shock or reoxygenation following hypoxia. The synthesis of Cu,Zn superoxide dismutase, but not Mn superoxide dismutase, was increased in rat lung slices by in vivo hyperthermia (39 degrees C), by in vitro heat shock (41 degrees C), and during incubation of lung slices with the Cu chelator diethyldithiocarbamate, which decreased the activity of Cu,Zn superoxide dismutase. The heat shock-induced increase in Cu,Zn superoxide dismutase developed 2 h later than the induction of heat shock proteins and was not blocked by actinomycin D. The rates of synthesis of both superoxide dismutases were decreased 50% by hypoxia and failed to increase during reoxygenation. During hypoxia the activity of Cu,Zn superoxide dismutase decreased about 50%, but the activity of Mn superoxide dismutase remained unchanged. We conclude that hyperthermia increases the synthesis of Cu,Zn superoxide dismutase, the synthesis of Cu,Zn superoxide dismutase and Mn superoxide dismutase are not coordinately regulated by hyperthermia or by the oxidant stress produced by lowering the activity of Cu,Zn superoxide dismutase, and the synthesis of heat shock proteins and Cu,Zn superoxide dismutase are regulated at different levels of gene expression.
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PMID:Regulation of the synthesis of superoxide dismutases in rat lungs during oxidant and hyperthermic stresses. 282 60

This study examined the effects of lung collapse, a condition that causes relative hypoxia in lung tissues, on superoxide dismutase (SOD), cytochrome oxidase (cyt ox), and pyruvate kinase (py ki) activities in rabbits. Cyanide-insensitive respiration measurements were done in collapsed and contralateral lungs, as an index of intracellular free radical production. Rabbits' right lungs were collapsed for 7 days after which the animals were killed. We found that control rabbit lungs contained approximately 25 SOD units/mg DNA measured with 10(-5) M KCN (total SOD) and approximately 11 SOD units/mg DNA measured with 10(-3) M KCN (mitochondrial or MnSOD). Right lung collapse caused a 25% decrease in mitochondrial SOD activity after 7 days (P less than 0.05), whereas no significant changes occurred in right or left lungs' total SOD activity. In control rabbits cyt ox activity averaged approximately 0.009 mumol ferrocytochrome c.min-1.mg DNA-1. Right lung collapse caused a greater than 40% decrease in cyt ox activity after 7 days of collapse (P less than 0.05), whereas cyt ox activity in contralateral left lungs did not change. Pyruvate kinase activity, a marker for anaerobic glycolysis resulting from tissue hypoxia, increased 49% in collapsed right lungs (P less than 0.01). Cyanide-insensitive respiration was 83% higher in 7 day-collapsed lungs (2.28 +/- 0.66 microliters O2.min-1.g-1) compared with contralateral lungs (1.24 +/- 0.34, P less than 0.05), indicating increased O2-. and H2O2 production in this tissue after homogenization at normoxic PO2 (approximately 150 Torr).(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Superoxide dismutase and cytochrome oxidase in collapsed lungs: possible role in reexpansion edema. 284 Dec 78

We studied the activity of superoxide dismutase (SOD) isoenzymes (CuZnSOD, cyanide-resistant MnSOD and extracellular SOD), the concentration of plasma selenium (P-Se), and the activities of CuZnSOD and glutathione peroxidase (GSHPx) in erythrocytes of 10 HLA-B27-positive and 10 HLA-B27-negative subjects whose sera had shown high and low chemokinetic activity, respectively, on migration of polymorphonuclear leukocytes (PMN) in vitro. No significant difference was found between the groups, suggesting that the enhanced chemokinetic activity of HLA-B27-positive sera does not derive from an aberration in serum anti-oxidant potentials. The results were also analysed on the basis of HLA-DR specificities; HLA-DR4-positive plasma samples had significantly lower levels of Se than HLA-DR4-negative ones. We therefore carried out a second series of experiments with sera of 37 subjects; the levels of P-Se in HLA-DR4-positive and -negative groups were much the same, as were the activities of GSHPx. The data suggest that there is no gross aberration in P-Se concentration in HLA-DR4-positive subjects.
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PMID:Superoxide dismutase isoenzymes, glutathione peroxidase and selenium in blood from HLA-B27-positive and -negative subjects. 349 90

The nuclear gene for manganese-containing superoxide dismutase (MnSOD; superoxide:superoxide oxidoreductase, EC 1.15.1.1) of yeast mitochondria was mapped on chromosome VIII and inactivated by gene disruption. The resulting mutant lacked any protein cross-reacting with anti-MnSOD antibodies, and its mitochondria exhibited less than 1% of the cyanide-insensitive superoxide dismutase activity found in mitochondria of the wild-type parent strain. In the absence of oxygen, the mutant grew as rapidly as the wild-type parent. However, increasing concentrations of oxygen led to a progressive inhibition of growth. The properties of this mutant provide direct evidence that MnSOD contributes to the natural protection of cells against oxygen toxicity.
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PMID:A yeast mutant lacking mitochondrial manganese-superoxide dismutase is hypersensitive to oxygen. 352 May 57

A further characterization of human extracellular superoxide dismutase is reported. The study was especially aimed at the interaction with substances known to interfere with CuZn superoxide dismutase and other superoxide dismutases. Extracellular superoxide dismutase is efficiently inhibited by cyanide and is about 3 times more sensitive than is human CuZn superoxide dismutase. The sensitivity to azide is much lower, but still about 3 times higher than that of human CuZn superoxide dismutase. Extracellular superoxide dismutase is about as rapidly inactivated by hydrogen peroxide as is CuZn superoxide dismutase. The sensitivity to diethyldithiocarbamate is very high and more than an order of magnitude larger than that of CuZn superoxide dismutase. Sodium dodecyl sulphate, under conditions suggested as being suitable for distinguishing between the insensitive CuZn superoxide dismutase and the sensitive Mn superoxide dismutase, efficiently inactivated extracellular superoxide dismutase. No antigenic similarities between extracellular superoxide dismutase and CuZn superoxide dismutase could be demonstrated. Anti-(extracellular superoxide dismutase) did not bind CuZn superoxide dismutase, and anti-(CuZn superoxide dismutase) did not bind extracellular superoxide dismutase.
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PMID:Properties of extracellular superoxide dismutase from human lung. 633 9


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