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)

A correlation between the changes in the rates of superoxide radical generation, upsilon, in microsomes, mitochondria, and nuclei and the Cu, Zn- and Mn-SOD activities in rat liver during the first 5 days after partial hepatectomy, has been studied. Level of upsilon in microsomal and mitochondrial membranes in the regeneration process was reduced. The Cu, Zn- and Mn-SOD activities changed in an extreme and antibate manner: the former was characterized by a minimum, whereas the latter-by a maximum with an extreme on the 3rd day after surgery. Analysis of the correlation between the values of upsilon in the nuclear membranes and cell cycle stages (on a literary basis) revealed that the upsilon was decreased 2 times on the stage of DNA synthesis. When mitosis was at maximum, upsilon showed a 4-5-fold increase in comparison with the control, the Cu, Zn-SOD activity being essentially unchanged. A role of SOD and O2-. in cell division is postulated. O2-. is assumed to play a role in gene expression, disassembly, and regeneration of the nuclear membrane; that of SOD is thought to consist in regulation of the proliferative activity.
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PMID:[Formation of superoxide radicals in membranes of subcellular organelles in regenerating liver]. 132 94

The expression of manganese-containing superoxide dismutase (sodA) in Escherichia coli using sodA::lacZ gene fusion was found to be stimulated by DNA gyrase inhibitors, nalidixic acid, or coumermycin A1. Aerobically, the gyrase inhibitors increased the expression of sodA::lacZ in the presence or absence of either paraquat or the iron chelator 2,2'-dipyridyl. The concentrations of the inhibitors used were found to reduce DNA supercoiling. Treatment of wild-type cells (sodA+) with nalidixic acid increased the transcription of MnSOD mRNA. Anaerobically, the expression of sodA::lacZ in wild-type cells was not affected by nalidixic acid. However, nalidixic acid had a stimulatory effect on the anaerobic expression of sodA::lacZ in cells preinduced by the iron chelator as well as in mutants derepressed in sodA expression by virtue of their lacking the trans-acting repressor proteins or the cis-acting regulatory elements needed for sodA regulation. The results indicate that the effect of DNA gyrase inhibitors is secondary to the cis- and trans-regulatory elements of sodA and suggest that changes in DNA topology may affect transcriptional regulation of sodA.
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PMID:Transcriptional regulation of Mn-superoxide dismutase gene (sodA) of Escherichia coli is stimulated by DNA gyrase inhibitors. 133 15

Superoxide dismutases are enzymes that defend against oxidative stress through decomposition of superoxide radical. Escherichia coli contains two highly homologous superoxide dismutases, one containing manganese (MnSOD) and the other iron (FeSOD). Although E. coli Mn and FeSOD catalyze the dismutation of superoxide with comparable rate constants, it is not known if they are physiologically equivalent in their protection of cellular targets from oxyradical damage. To address this issue, isogenic strains of E. coli containing either Mn or FeSOD encoded on a plasmid and under the control of tac promoter were constructed. SOD specific activity in the Mn and FeSOD strains could be controlled by the concentration of isopropyl beta-thiogalactoside in the medium. The tolerance of these strains to oxidative stress was compared at equal Mn and FeSOD specific activities. Our results indicate that E. coli Mn and FeSOD are not functionally equivalent. The MnSOD is more effective than FeSOD in preventing damage to DNA, while the FeSOD appears to be more effective in protecting a cytoplasmic superoxide-sensitive enzyme. These data are the first demonstration that Mn and FeSOD are adapted to different antioxidant roles in E. coli.
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PMID:Functional differences between manganese and iron superoxide dismutases in Escherichia coli K-12. 144 75

In subcellular systems, doxorubicin hydrochloride (ADR) leads to the generation of reactive oxygen species such as superoxide anion. Because reactive oxygen species have been shown to be important mediators of glomerular injury in several animal models, we sought to determine whether reactive oxygen species play a significant role in the pathogenesis of ADR-induced nephrotic syndrome in the rat. Rats pretreated with a variety of free radical scavengers (superoxide dismutase conjugated to polyethylene glycol [PEGSOD], catalase, catalase plus PEGSOD, dimethylsulfoxide, desferoxamine, or n-acetyl cysteine) had no significant reduction in proteinuria at 3 weeks after ADR administration when compared with rats receiving ADR in the absence of scavengers. No evidence was seen of increased lipid peroxidation or depletion of reduced glutathione in renal cortex tissue obtained up to 24 hours after administration of ADR. No changes were seen in the renal cortical levels of either enzyme activity or immunoreactive protein for the endogenous antioxidant enzymes superoxide dismutase (either the Mn or CuZn forms) or catalase after ADR. Total and MnSOD activities in glomeruli isolated from rats after ADR administration fell significantly, though CuZnSOD activity was increased. The effect of ADR on cultured rat mesangial or epithelial cells was also evaluated. ADR inhibited growth of both cell types at concentrations of approximately 5 to 10 mumol/L, an order of magnitude below the reported Michaelis-Menten constant for ADR-induced superoxide production. The growth inhibitory effect could not be prevented in either cell type by treatment with PEGSOD, catalase, or PEGSOD plus catalase. This combination of results from in vivo and in vitro studies provides no evidence for an important role of reactive oxygen species in ADR nephrosis and suggests that other known mechanisms of ADR cytotoxicity, such as interference with DNA metabolism, mediate the glomerular injury.
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PMID:Evaluation of the role of reactive oxygen species in doxorubicin hydrochloride nephrosis. 194 May 84

The distribution of cells containing copper-zinc superoxide dismutase (CuZn SOD) protein and mRNA was studied in hippocampi from normal humans and patients with Alzheimer's disease (AD) by using immunohistochemistry and in situ hybridization. Using antisera against native and denatured CuZn SOD protein, we have determined that immunostaining was intense in pyramidal neurons of the cornu ammonis, in granule cells of the dentate gyrus and very weak in other cells. In the hippocampus of an Alzheimer's patient, successive immunostaining of the same tissue section by antiCuZn SOD and antipaired helical filaments antisera show that both normal and degenerating cells were labeled by the antiCuZn SOD antiserum. Thus, large pyramidal neurons which are susceptible to degenerative processes in AD have the property to contain high amount of CuZn SOD protein. In situ hybridization was performed on paraformaldehyde-fixed hippocampus sections of normal human brains and AD brains with a 35 S labeled DNA probe homologous to human CuZn SOD mRNA. Our results show that CuZn SOD transcripts are present at high abundance in pyramidal neurons of the CA1-CA4 fields, subiculum, and in granule cells of the dentate gyrus. This cellular distribution is similar to that obtained with the antiCuZn SOD antiserum. This might indicate that biochemical pathways leading to superoxide radicals generation are specially active in these neurons, requiring an active transcription of CuZn-SOD gene.
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PMID:Neuronal localization of copper-zinc superoxide dismutase protein and mRNA within the human hippocampus from control and Alzheimer's disease brains. 206 Aug 34

A 1.8 kb PstI fragment from Halobacterium halobium DNA was found to hybridize to synthetic oligonucleotide probes constructed by using the sequence of the N-terminus of a Mn-containing superoxide dismutase purified from H. halobium. The entire insert containing a 600-bp coding sequence for Mn-SOD and its 5' and 3' flanking regions was sequenced. The derived amino acid sequence of the structural gene showed a similarity to other manganic and iron-containing superoxide dismutases in normally conserved regions. Primer extension analysis of the H. halobium Mn-SOD mRNA showed that gene transcription begins 14 bases upstream of the translational start. A Shine-Dalgarno sequence and archaebacterial consensus promoter sequences were observed. Several other promoter and terminator nucleotide sequences homologous to prokaryotic and eukaryotic organisms were found.
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PMID:Halobacterium halobium Mn-SOD gene: archaebacterial and eubacterial features. 207 Oct 48

The ferric uptake regulation (fur) gene product participates in regulating expression of the manganese- and iron-containing superoxide dismutase genes of Escherichia coli. Examination of beta-galactosidase activity coded from a chromosomal phi(sodA'-'lacZ) fusion suggests that metallated Fur protein acts as a transcriptional repressor of sodA (manganese superoxide dismutase [MnSOD]). Gel retardation assays demonstrate high-affinity binding of pure, Mn2(+)-Fur protein to DNA fragments containing the sodA promoter. These data and the presence of an iron box sequence in its promoter strongly suggest that sodA is part of the iron uptake regulon. An sodB'-'lacZ fusion gene borne on either a low- or high-copy plasmid yielded approximately two- to threefold more beta-galactosidase activity in Fur+ compared with Fur- cells; the levels of activity depended only weakly on the growth phase and did not change during an extended stationary phase. Measurement of FeSOD activity in logarithmic growth phase and in overnight cultures of sodA and fur sodA backgrounds revealed that almost no FeSOD activity was expressed in Fur- strains, whereas wild-type levels were expressed in Fur+ cells. Fur+ and Fur- cells bearing the multicopy plasmid pHS1-4 (sodB+) expressed approximately sevenfold less FeSOD activity in the fur background, and staining of nondenaturing electrophoretic gels indicates that synthesis of FeSOD protein was greatly reduced in Fur- cells. Gel retardation assays show that Mn2(+)-Fur had a significantly higher affinity for the promoter fragment of sodB compared with that of random DNA sequences but significantly lower than for the promoter fragment of sodA. These observations suggest that the apparent positive regulation of sodB does not result exclusively from a direct interaction of holo (metallated) Fur itself with the sodB promoter. Nevertheless, the sodB gene also appears to be part of the iron uptake regulon but not in the classical manner of Fe-dependent repression.
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PMID:Control of Escherichia coli superoxide dismutase (sodA and sodB) genes by the ferric uptake regulation (fur) locus. 218 Sep 12

Antioxidant enzyme activities, superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GSH-Px) and total glutathione concentration were determined in guinea pig lung and liver over the final period of gestation (days 50-68) and at several ages post-partum. Pulmonary antioxidant capacity increased markedly over the final days of gestation, individual changes ranging from 29% (glutathione) to 198% (GSH-Px). Liver antioxidant capacity was always 4-fold to 10-fold greater than that of the lung and exhibited very similar developmental profiles to those observed in the lung. From day 60 gestation to term (68 days), activity of the liver antioxidants increased, ranging from 246% (CAT) to 610% (glutathione). A number of antioxidants in both lung and liver exhibited either immediate pre- or post-birth decreases in activity. These falls could not be attributed to the way in which the results were expressed: i.e. they were similar, expressed per unit DNA, per unit protein, or per g wet wt. Following birth, liver antioxidant capacity increased such that the highest enzyme activities or glutathione concentration were recorded at 66 days post-partum. In lung, only Mn-SOD and glutathione exhibited higher levels at 66 days postpartum than at birth. In combination, these results of pulmonary and hepatic antioxidant enzyme activity indicate that the lung is not unique in acquiring increased antioxidant protection in the final period of gestation. They also suggest that a tissue's antioxidant requirement is dictated more by metabolic rate (hence free radical production) than incident partial pressure of oxygen.
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PMID:Developmental expression of antioxidant enzymes in guinea pig lung and liver. 235 Oct 72

We describe the isolation of a cDNA clone for the nuclear-encoded manganese superoxide dismutase (SOD-3) of maize mitochondria. The cDNA, pSod3.1c, selects by hybridization an RNA which produces the SOD-3 precursor upon in vitro translation. The DNA sequence of pSod3.1c was determined from fragments subcloned in M13. The amino-acid sequence deduced from the nucleotide sequence displays significant homology with the amino-acid sequences of prokaryotic and eukaryotic Mn-SODs, but displays greater homology with mammalian Mn-SOD than it does with yeast or bacterial Mn-SOD. A 31 amino-acid transit peptide also is encoded by the pSod3.1c clone. Analysis of poly(A)+ RNA indicates that Sod3 mRNA is approx. 1250 nucleotides in length. The amount of Sod3 transcript in seedling leaves is increased by light.
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PMID:Isolation and characterization of a cDNA for mitochondrial manganese superoxide dismutase (SOD-3) of maize and its relation to other manganese superoxide dismutases. 246 Dec 25

Earlier histological studies have demonstrated that copper deficiency results in a selective and progressive atrophy of pancreatic acinar tissue. The present study examined both biochemical and morphological changes of the exocrine pancreas in nutritional copper deficiency. Groups of mature female rats were fed a purified diet either deficient (less than 0.5 micrograms/g) or sufficient (6.2 micrograms/g) in copper for 6 wk. Copper deficiency resulted in distinct ultrastructural changes in acinar cells, including marked variability in zymogen granule content, autophagic vacuoles and dilation of acinar lumen. Pancreatic weight and total DNA, RNA and protein content of the pancreas were similar in both groups of rats, whereas pancreatic amylase, trypsin and chymotrypsin activity was significantly lower in the copper-deficient group. In addition, secretagogue-induced release of these enzymes from dispersed acini isolated from copper-deficient rats was significantly reduced in comparison to enzyme secretion from normal controls. Pancreatic Cu-Zn and Mn superoxide dismutase activity was also found to be significantly lower in the copper-deficient rats than in normal controls. We conclude that nutritional copper deficiency in adult female rats reduces the responsiveness of the pancreas to secretagogues and may increase the susceptibility of the pancreas to oxidative damage.
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PMID:Morphological and biochemical changes in the pancreas of the copper-deficient female rat. 247 34


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