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)

Alzheimer's disease (AD) has been hypothesized to be associated with oxidative stress. In this study, the expression of key oxidative stress-handling genes was studied in hippocampus, inferior parietal lobule, and cerebellum of 10 AD subjects and 10 control subjects using reverse transcriptase-polymerase chain reaction (RT-PCR). The content of Mn-, Cu,Zn-superoxide dismutases (Mn- and Cu,Zn-SOD), catalase (CAT), glutathione peroxidase (GSH-Px), and glutathione reductase (GSSG-R) mRNAs, and the "marker genes" (beta-actin and cyclophilin) mRNAs was determined. This study suggests that gene responses to oxidative stress can be significantly modulated by the general decrease of transcription in the AD brain. To determine if the particular oxidative stress handling gene transcription was induced or suppressed in AD, the "oxidative stress-handling gene/beta-actin" ratios were quantified and compared with control values in all brain regions studied. The Mn-SOD mRNA/beta-actin mRNA ratio was unchanged in all regions of the AD brain studied, but an increase of the Cu,Zn-SOD mRNA/beta-actin mRNA ratio was observed in the AD inferior parietal lobule. The levels of peroxidation handling (CAT, GSHPx, and GSSG-R) mRNAs normalized to beta-actin mRNA level were elevated in hippocampus and inferior parietal lobule, but not in cerebellum of AD patients, which may reflect the protective gene response to the increased peroxidation in the brain regions showing severe AD pathology. The results of this study suggest that region-specific differences of the magnitude of ROS-mediated injury rather than primary deficits of oxidative stress handling gene transcription are likely to contribute to the variable intensity of neurodegeneration in different areas of AD brain.
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PMID:The expression of key oxidative stress-handling genes in different brain regions in Alzheimer's disease. 1009 42

Cardiac and skeletal muscle are very different functional tissues, and we would expect a variation in the ROS generation, in ageing and rigorous exercise-related in both tissues. We determined TBARS, total SOD, Cu, ZnSOD and MnSOD activities, and the patterns of SOD isoenzymes in skeletal muscle and heart of male Wistar rats, young and old, in rest and after rigorous exercise. There were no differences in the levels of lipoperoxidation in aged rest animals in both tissues, but the level was increased after exhaustion. The level of SOD activities was bigger in the heart than in skeletal muscle. Total SOD and Cu, ZnSOD activities were higher in old rest animals in the skeletal muscle than in young rest rats. This change did not occur in the heart. After rigorous exercise, the level of SOD activities was increased in young rats in both tissues. However, in old exhausted rats, the activities were only elevated in the heart. Different Cu, ZnSOD isoenzyme patterns showed in relation to tissues. In the skeletal muscle in old animals, the Cu, ZnSOD isoenzyme pattern was modified. The rigorous exercise did not change this pattern. The pattern of MnSOD isoenzyme was not varied in either tissue, age nor and exercise.
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PMID:Myocardial and skeletal muscle aging and changes in oxidative stress in relationship to rigorous exercise training. 1040 81

Reactive oxygen species (ROS; O2-, H2O2, and OH), normal by-products of cellular metabolic processes, are kept in control by antioxidant enzymes, such as catalase, glutathione peroxidase (GPX) and superoxide dismutases (SODs). To understand the role of antioxidant enzymatic defenses against ROS injury following ischemia-reperfusion, we examined the effect on kidney exposed to varying periods (30, 60 or 90 min) of ischemia followed by different periods of reperfusion. The enzymatic activities and protein levels of catalase, GPX, CuZnSOD and MnSOD were relatively unaffected at 30 min of ischemia followed by 0, 2 or 24 h reperfusion. However, 60 or 90 min of ischemia followed by 0, 2 or 24 h of reperfusion resulted in a decrease in activities and protein levels which paralleled the duration of ischemic injury. MnSOD activity tended to recover towards normal during reperfusion. Examination of the mRNA levels of these antioxidant enzymes demonstrated a severe decrease in mRNA levels of catalase and GPX at a time point of minimal ischemic injury (30 min of ischemia followed by reperfusion) suggesting that loss of mRNA of catalase and GPX may be the first markers of alterations in cellular redox in ischemia-reperfusion injury. Greater loss of mRNA for catalase, GPX and CuZnSOD was observed following longer periods (60 or 90 min) of ischemia. The mRNA for MnSOD was upregulated at all time points of ischemia-reperfusion injury. Actually, the greater decrease in mRNAs for catalase, GPX and CuZnSOD in the acute phase (within 24 h) subsequently showed a further decrease in these enzyme activities in the subacute phase (72 or 120 h after ischemia). These enzyme activities in the 30 min ischemia group, (but not in the 90 min group), already showed tendencies for normalization at 120 h after ischemia. To understand the molecular basis of the loss of mRNA of these antioxidant enzymes during ischemia-reperfusion injury, we examined the rate of transcription by nuclear run-on assays. The similar rates of transcription in control and kidney exposed to ischemia-reperfusion indicates that the loss of mRNA for catalase, GPX and CuZnSOD is possibly due to the increased rate of turnover of their mRNAs. These studies suggest that expression of antioxidant genes during ischemia-reperfusion are not coordinately expressed and that the differential loss of antioxidant enzymes may be the contributing factor(s) towards the heterogeneous renal tissue damage as a result of ischemia-reperfusion induced oxidative stress.
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PMID:Kidney ischemia-reperfusion: modulation of antioxidant defenses. 1082 17

The cytostatic Adriamycin and the herbicide paraquat form reactive oxygen species during enzymatic activation. Adriamycin, but not paraquat, is also able to intercalate into DNA and to interfere with DNA synthesis and transcription. We investigated the influence of both substances on antioxidant enzyme expression in primary rat hepatocytes. Treatment of hepatocytes with Adriamycin led to an increase in catalase and a decrease in MnSOD mRNA expression. In contrast, exposure of hepatocytes to paraquat resulted in an increase in both catalase and MnSOD message levels. CuZnSOD mRNA was not responsive to either treatment. Adriamycin almost completely inhibited RNA synthesis, but paraquat did not change either RNA or protein synthesis. Both substances induced lipid peroxidation as measured by the accumulation of malondialdehyde in the medium. These findings indicate that catalase and MnSOD are not regulated coordinately in hepatocytes and that ROS-producing agents can differentially influence expression of antioxidant enzymes depending on their capacity to inhibit transcription.
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PMID:Influence of Adriamycin and paraquat on antioxidant enzyme expression in primary rat hepatocytes. 1095 98

Primary glial cultures are able to express the inducible isoform of nitric oxide synthase (i-NOS) upon stimulation by bacterial lipopolysaccharides (LPS) and gamma-interferon (gamma-IfN). Immunocytochemical studies revealed, that under our experimental conditions i-NOS is expressed exclusively by the microglial cells and not in the astrocytes. Nitric oxide (NO) formation represents an oxidative load for the microglial cells, as observed by the oxidation rate of the ROS- and peroxynitrite indicator dichloro-dihydrofluorescein (DCF-H) in these cells. However, cell viability was not affected by the nitric oxide formation, indicating some form of protection against the higher oxidative load. Upregulation of Mn-SOD in the mitochondria in the course of the induction of i-NOS and, compared to the astrocytes, higher GSH levels in the microglial cells probably explain the resistance of the cultures against nitrosative stress. Increased SOD-activities in the mitochondria could lower the superoxide concentration in this organelle and may prevent an oxidative and/or nitrosative damage via a decreased peroxynitrite formation. The higher GSH-levels in the microglial cells of unstimulated cultures represents a buffer which, under the conditions of i-NOS catalyzed NO-formation, prevents a decline of the microglial GSH-levels below that of the astrocytes.
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PMID:Nitrosative stress in primary glial cultures after induction of the inducible isoform of nitric oxide synthase (i-NOS). 1096 32

Based on recent evidence that nitric oxide (NO(.)) is involved in hyperoxic vasoconstriction, we tested the hypothesis that decreases in NO(.) availability in brain tissue during hyperbaric oxygen (HBO(2)) exposure contribute to decreases in regional cerebral blood flow (rCBF). rCBF was measured in rats exposed to HBO(2) at 5 atmospheres (ATA) and correlated with interstitial brain levels of NO(.) metabolites (NO(X)) and production of hydroxyl radical ((.)OH). Changes in rCBF were also correlated with the effects of NO(.) synthase inhibitor (l-NAME), NO(.) donor PAPANONOate, and intravascular superoxide dismutase (MnSOD) during HBO(2). After 30 min of O(2) exposure at 5 ATA, rCBF had decreased in the substantia nigra, caudate putamen, hippocampus, and parietal cortex by 23 to 37%. These reductions in rCBF were not augmented by exposure to HBO(2) in animals pre-treated with l-NAME. After 30 min at 5 ATA, brain NO(X) levels had decreased by 31 +/- 9% and correlated with the decrease in rCBF, while estimated (.)OH production increased by 56 +/- 8%. The decrease in rCBF at 5 ATA was completely abolished by MnSOD administration into the circulation before HBO(2) exposure. Doses of NO(.) donor that significantly increased rCBF in animals breathing air had no effect at 5 ATA of HBO(2). These results indicate that decreases in rCBF with HBO(2) are associated with a decrease in effective NO(.) concentration and an increase in ROS production in the brain. The data support the hypothesis that inactivation of NO(.) antagonizes basal relaxation of cerebral vessels during HBO(2) exposure, although an effect of HBO(2) on NO(.) synthesis has not been excluded.
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PMID:Hyperbaric oxygen reduces cerebral blood flow by inactivating nitric oxide. 1113 68

Dietary copper- and iron restriction was achieved by application of the whole milk diet to growing rats in the course of 50 days. Three distinct responses of cytosolic and mitochondrial aconitases as well as of antioxidant defense system (CuZnSOD, MnSOD, catalase and GSH) to the dietary copper- and iron deficiency were established in liver, kidney and heart from experimental rats. The results were discussed with a view to the participation of ROS-generating processes in copper- and iron-deficient state. Differences in oxidative stability of cytosolic and mitochondrial aconitase activity of both control and experimental rats were also found. The in vitro increased aconitase activity of cytosol and the unchanged one of mitochondria from liver upon exposure of preparations to air were proved in vivo upon dietary copper- and iron restriction. This finding was interpreted to suggest the existence of putative aconitase activity.
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PMID:Effect of dietary copper and iron restriction on aconitase activity and antioxidant capacity of liver, kidney and heart from growing rats. 1114 Jan 69

NF-kappaB is known to exert a cytoprotective action against TNF-alpha-induced apoptosis. To study the role of NF-kappaB in various TNF-alpha-treated epithelial cell lines, we generated stable transfectants overexpressing a mutated unresponsive form of the IkappaBalpha inhibitor (MT cells). As NF-kappaB prevented TNF-alpha-induced apoptosis in various epithelial cancer cell lines, we searched for NF-kappaB target gene products responsible for this difference of sensitivity. We observed an increased Bcl-X(L) expression level in OVCAR-3 cells compared with OVCAR-3 cells expressing a mutated IkappaBalpha inhibitor (MT cells). Induction of the antioxidant enzyme MnSOD was detected only in TNF-alpha-treated OVCAR, MCF7A/Z and HCT116 cells but not in MT cells. Moreover, reactive oxygen species were involved in TNF-alpha-induced apoptosis, as various antioxidants partially protected these cells from apoptosis. At last, transfection of the MnSOD cDNA in MT cells, which do not express this protein after TNF-alpha stimulation, partially restored resistance to TNF-alpha-induced cell death, as observed by clonogenic assays. However, transfection of the Bcl-X(L) cDNA did not induce any protective effect. Therefore, MnSOD expression is induced by NF-kappaB in epithelial cancer cells in response to TNF-alpha, and is at least partially responsible for their resistance to TNF-alpha-induced apoptosis, presumably through the clearance of death-inducing ROS.
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PMID:NF-kappaB-dependent MnSOD expression protects adenocarcinoma cells from TNF-alpha-induced apoptosis. 1203 30

Cyclosporine A (CsA) is the immunosuppressor most frequently used in transplant surgery and in the treatment of autoimmune diseases. It has been shown that CsA is able to generate reactive oxygen species and lipid peroxidation which are directly involved in the CsA hepatotoxicity. As antioxidant, Vitamin E (VitE) has been used to diminish the toxicity of CsA in vitro. Besides its direct action as the classical antioxidant implicated in preventing lipid peroxidation, we decided to investigate the effect of VitE on the endogenous antioxidant defense system, such as Mn and CuZn superoxide dismutase (MnSOD, CuZnSOD) catalase and glutathione peroxidase (GPx) on CsA cytotoxicity in primary cultures of rat hepatocytes. In cells incubated in the presence of CsA, there was an increase in the expression and activity of MnSOD and CuZnSOD but not in that of catalase and GPx. However, when hepatocytes were coincubated with CsA and VitE, an increase in the expression and activity in all antioxidant enzymes (MnSOD, CuZnSOD, catalase and GPx) was observed. In conclusion, we suggest (a) that the imbalance between SOD and catalase/GPx by the effect of CsA is the main mechanism responsible for peroxide accumulation and cell death in hepatocytes, and (b) that the presence of VitE in culture media reduces the oxidative stress through the inhibition of lipid peroxidation, but also through the increase of the expression and activity of catalase and GPx which allows the restoration of SOD and catalase/GPx coordination, indispensable for the correct cell defense against ROS.
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PMID:Novel mechanism of Vitamin E protection against cyclosporine A cytotoxicity in cultured rat hepatocytes. 1212 47

The influence of a short-time isobaric hypoxia as well as reoxygenation on markers of oxidative stress (MDA, total SOD, GSH) and on the mRNA expression of the antioxidative enzymes (Cu/Zn-and Mn-SOD, catalase, GSH reductase and GSH peroxidase) has been studied in liver and kidneys of young (6 months) and old (22-25 months) Wistar rats. In livers of old animals, the concentration of GSH, the activity of SOD, and the mRNA expression of the antioxidative enzymes (except Mn-SOD) points to a restricted protection against oxidative stress or a lower production of ROS compared to young animals. Hypoxia resulted in a significant decrease of enzyme gene expression in both age groups. Reoxygenation caused an increase in mRNA of Cu/Zn-SOD and GPX in livers of young and of Mn-SOD in livers of old animals. In kidneys, gene expression of Cu/Zn-SOD, GSH reductase, and GPX was significantly higher in old animals compared to young animals. Whereas hypoxia caused a decrease of gene expression in the livers, it lead to a significant increase of Cu/Zn-SOD, catalase, and GSH reductase mRNA in kidneys of young rats. A reduced gene expression was observed after reoxygenation. In old kidneys, the expression of all enzymes except for catalase progressively declined in the hypoxic and reoxygenation groups. These data show that gene expression of antioxidative enzymes is affected by age and significantly differs between liver and kidney.
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PMID:Effect of age and hypoxia/reoxygenation on mRNA expression of antioxidative enzymes in rat liver and kidneys. 1255 17


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