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)

Preconditioning the heart with 5 min of ischemia renders the heart very resistant to infarction from subsequent ischemia by an unknown mechanism. We investigated whether the protective effect of preconditioning might be related to an increase in rabbit heart antioxidant defenses. The antioxidant activities of catalase, glutathione peroxidase, Mn superoxide dismutase, Cu,Zn superoxide dismutase, glucose-6-phosphate dehydrogenase, glutathione reductase, and total glutathione were measured in ischemic and normal regions from both control and preconditioned rabbit hearts. All hearts experienced 30 min regional ischemia and 5 min reperfusion. None of the antioxidant enzymes changed in activity when comparing nonischemic and postischemic zones in either nonpreconditioned or preconditioned hearts. Total glutathione, however, was reduced in reperfused zones and showed better preservation in preconditioned hearts. To determine whether this preservation resulted from a higher value at the onset of reperfusion or slower washout during reperfusion, we analyzed a second group of nonreperfused hearts after 30 min ischemia. The hearts had normal glutathione content in both ischemic and nonischemic zones of either preconditioned or control hearts. The most likely explanation is that preconditioned hearts experienced less washout of glutathione simply because they were less injured. We therefore conclude that enhancement of antioxidant defenses is not the mechanism of preconditioning.
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PMID:Protection from reperfusion injury by preconditioning hearts does not involve increased antioxidant defenses. 153 19

The activities of superoxide dismutase (SOD), catalase, glutathione peroxidase, glutathione S-transferases, GSSG reductase, thiol transferases, gamma glutamylcysteine synthetase, and glucose-6-phosphate dehydrogenase, and the concentrations of H2O2 and reduced and oxidized glutathione were determined in the various developmental stages of houseflies. Housefly development was correlated with a progressive increase of cellular oxidizing equivalents and a loss of cellular reducing capacity. The loss of reducing equivalents appeared to result from a decrease in the activity of enzymes involved in glutathione and NADPH synthesis and a concomitant increase in glutathione-oxidizing enzymes. Relatively little change was observed in SOD activity during housefly development; however, the electrophoretic pattern of MnSOD varied in a manner specific to developmental stage. A striking increase in H2O2 concentration occurred prior to pupation possibly due to changes in substrate catabolism. These results support the hypothesis that the cellular environment becomes progressively more oxidizing during development.
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PMID:Developmental patterns in the antioxidant defenses of the housefly, Musca domestica. 199 75

1. A number of dietary sugars are known to mediate the effects of copper deficiency. The effects of lactose (compared with sucrose) and a dietary Cu deficiency on hepatic and cardiac antioxidant enzyme activities and tissue mineral element status were investigated in the rat. 2. Groups (n 6) of male weanling Wistar rats were provided ad lib. with deionized water and diets containing sucrose (580 g/kg) or sucrose and lactose (387 g/kg and 193 g/kg respectively) with either control (12.0 mg/kg) or deficient (1.5 mg/kg) quantities of Cu for 77 d. 3. Animals consuming the low-Cu diets exhibited significantly decreased tissue Cu levels (P less than 0.01), hepatic and cardiac cytochrome c oxidase (EC 1.9.3.1, CCO) activities (P less than 0.01 and P less than 0.001 respectively) and hepatic Cu-zinc superoxide dismutase (EC 1.15.1.1, CuZnSOD) activity (P less than 0.05). The low-Cu diets also significantly decreased cardiac manganese superoxide dismutase (EC 1.15.1.1, MnSOD), catalase (EC 1.11.1.6) and glutathione peroxidase (EC 1.11.1.9, GSH-Px) activities (P less than 0.01, P less than 0.05 and P less than 0.001 respectively). 4. Hepatic Mn was significantly increased in both lactose-fed (P less than 0.001) and Cu-deficient (P less than 0.01) animals. These increases were unrelated to hepatic MnSOD activity. Cardiac Zn was significantly (P less than 0.01) increased in Cu-deficient animals. 5. Lactose feeding resulted in significantly increased cardiac CCO activity (P less than 0.001) but significantly decreased hepatic CuZnSOD (P less than 0.05), catalase (P less than 0.01) and GSH-Px (P less than 0.001) activities. 6. The activities of lactose dehydrogenase (EC 1.1.1.27, LDH) and glucose-6-phosphate dehydrogenase (EC 1.1.1.49, G6PDH) were found to be significantly (P less than 0.05 and P less than 0.01 respectively) increased in Cu-deficient animals and G6PDH activity was significantly (P less than 0.01) decreased as a result of lactose consumption. 7. The observed changes in antioxidant enzyme activities associated with both Cu deficieny and lactose consumption may have important implications for the development of free radical mediated cell damage. However, no significant differences in either hepatic or cardiac levels of thiobarbituric acid reactive substances, a measure of lipid peroxidation, were found.
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PMID:Effects of copper deficiency on hepatic and cardiac antioxidant enzyme activities in lactose- and sucrose-fed rats. 253 51

The activity of antioxidant enzymes were measured in alveolar type II cells isolated from control and 85% oxygen-exposed rats to determine if type II cells, an oxygen-resistant lung cell type had constitutively high enzyme activities and to measure the effect of hyperoxia on these antioxidant enzyme. Type II cells were isolated from lungs of control rats and rats exposed to 85% O2 for 7 days. In whole lungs of rats exposed to 85% oxygen there is an increase in activity (per lung or per mg lung DNA) in the antioxidant enzymes CuZn superoxide dismutase, Mn superoxide dismutase, catalase, glutathione peroxidase and glucose-6-phosphate dehydrogenase. Oxygen exposure significantly increased (p less than 0.05) all type II cell antioxidant enzyme activities when expressed per mg DNA. The protein content of oxygen exposed type II cells increased 25% from (63.9 +/- 4.8 micrograms/10(6) cells to 79.6 +/- 4.2 micrograms/10(6) cells, p less than 0.05). When type II cell enzyme activities were expressed in U/mg cell protein, only CuZn superoxide dismutase and Mn superoxide dismutase increased in activity following oxygen exposure (by 43% and 28% relative to air exposed lung type II cells, respectively, p less than 0.05). This suggested that most lung cell antioxidant enzymes increased in activity following oxidant stress in proportion to increased cell mass. CuZn and Mn superoxide dismutase increased activity to an extent greater than the increase in type II cell protein content after oxygen exposure. Alveolar macrophages lavaged from control and oxygen-exposed rats were also evaluated, and they had no significant change in CuZn and Mn superoxide dismutase activities. Type II cells accounted for 10% and 17% of alveolar cells in control and oxygen treated rats. By knowing the antioxidant enzyme activities in type II cells, the total enzyme activity of whole lung and the number of type II cells in control and oxygen exposed rats from morphometric data, we calculated the percent of whole lung enzyme activity accounted for by type II cells. Type II cells accounted for a high percentage of lung glucose-6-phosphate dehydrogenase (58% in control rats, 65% in oxygen exposed rats) but a low percentage of Mn superoxide dismutase (4% in control rats, 6% in oxygen exposed rats).
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PMID:Antioxidant enzyme activity in alveolar type II cells after exposure of rats to hyperoxia. 300 82

In this work comprehensive data of antioxidant enzymes are reviewed and their role in carcinogenesis is discussed. When compared to their normal tissue counterparts, more of the tumor tissues were low in Cu, Zn-SOD and catalase activity and in some cases in Mn-SOD. It is probably characteristic for tumor tissues. Glutathione peroxidase, and glutathione reductase and glucose-6-phosphate dehydrogenase activities are highly variable. The reason why cancerous cells exhibit abnormal levels and activities of antioxidant enzymes is unknown. It was hypothesized, that during formation of the tumor, by certain obscure mechanism, cells with imbalance of antioxidant enzymes profile were selected over normal cells. It is not known whether the changes in antioxidant defence observed in cancerous tissues play a role in carcinogenesis, or are formed as a results of the disease.
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PMID:[Activity of antioxidant enzymes in cancer diseases]. 763 95

Rats weighing 45-50 g were fed 3 diets for 8 wk: a balanced control diet (CD) consisting of 4% fat (polyunsaturated/saturated fatty acids [P/S] ratio 2.9/1) and two fat-rich diets: polyunsaturated (UD)--P/S 7.6/1 and saturated (SD) P/S 0.3/1. After 8 wk feeding on the respective diets, rats were subjected to swimming for 90 min at 30 degrees C daily, 5 d/wk for 8 wk. At the end of this period, the rats were killed and the lymphoid organs (LO--thymus, spleen, and mesenteric lymph nodes) and muscles (soleus and gastrocnemius) removed for the measurement of TBARs (Thiobarbituric Acid Reactant Substances) content and of the activities of antioxidant enzymes (CuZn- and Mn-Superoxide dismutase--SOD--, catalase, and glutathione peroxidase). To evaluate the changes in the sites of generation of reducing equivalents involved in the formation of free radicals, the activities of citrate synthase and glucose-6-phosphate dehydrogenase were measured. The exercise-training clearly modified the enzyme activities and TBARs content of the lymphoid organs and skeletal muscles, but this effect was dependent upon the diet given to the rats. However, fatty acid rich diets had presented a more pronounced effect on the studied aspects than did physical activity. Although one could expect a summatory effect of polyunsaturated fatty acid-rich diet and exercise-training, swimming increased the activities of CuZn- and Mn-SOD in almost all tissues from the elevated level promoted by fat-rich diets.
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PMID:Antioxidant enzyme activities in the lymphoid organs and muscles of rats fed fatty acids-rich diets subjected to prolonged physical exercise-training. 782 70

The effect of swimming-training upon the activities of the enzymes involved in the generation of reducing-equivalents (citrate synthase-mitochondria and glucose-6-phosphate dehydrogenase-cytosol) and of antioxidant enzymes (CuZn- and Mn-SOD, catalase and glutathione peroxidase) in the lymphoid organs (thymus, mesenteric lymph nodes and spleen) was examined. The skeletal muscles (soleus-red and gastrocnemius-white) were also studied. Although our data suggest an apparently random, organ-specific change in enzymatic activity, some interesting trends can be observed. Firstly, the increased citrate synthase and Mn-SOD activities observed in red, but not in white muscle, corroborate the well-known effect of endurance exercise-training on mitochondrial oxidative metabolism. Secondly, there was an inverse relationship between TBARs-monitored lipoperoxidation and glutathione peroxidase activity in all tissues studied, what is in accordance with the previous findings showing that such enzyme exerts the fine control of intracellular lipoperoxide concentration. Except in the case of the spleen, there was a trend for elevated glucose-6-phosphate dehydrogenase activity, coadjuvant of glutathione peroxidase in the antioxidant response to physical exercise in all tissues. Thirdly, Mn-SOD and catalase were conspicuously associated to oxidative stress in the thymus, while glutathione and catalase could be linked to this parameter in the spleen. Fourthly, the lymph nodes seem to be more dependent on the glucose-6-phosphate dehydrogenase/glutathione peroxidase pair for protection against damage promoted by physical exercise. Mn-SOD and catalase activities were lower in the lymph nodes after swimming training.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Superoxide dismutase, catalase, and glutathione peroxidase activities in muscle and lymphoid organs of sedentary and exercise-trained rats. 782 77

The effect of alloxan-induced diabetes on CuZn- and Mn-superoxide dismutase (SOD), catalase and glutathione peroxidase (GPX) activities, as well as the content of thiobarbituric acid reactive substances (TBARs) were examined in rat lymphoid organs (mesenteric lymph nodes (MLN), thymus and spleen) and, for comparison, red and white muscle fibres. The capacity for generation of reduced equivalents was also evaluated by measuring the activities of glucose-6-phosphate dehydrogenase (pentose-phosphate pathway-cytosol) and citrate synthase (Krebs cycle-mitochondria). Diabetes raised the capacity for the generation of reducing equivalents in the lymphoid organs: in the mitochondria of the thymus and spleen and in the cytosol of the mesenteric lymph nodes and thymus. In muscles, diabetes reduced CuZn-SOD activity in soleus and raised the activity in gastrocnemius, and depressed the activities of catalase in soleus and of glutathione peroxidase in both soleus and gastrocnemius. In relation to the lymphoid organs, the spleen showed a decrease in the antioxidant enzyme activities (except for glutathione peroxidase), whereas the thymus showed an increased level (except for Mn-SOD), and the MLN presented a reduction in Mn-SOD and catalase activities and an increase in GPX activity caused by diabetes. The content of TBARs in the tissues followed the changes in GPX activity inversely: i.e. a decrease in the lymphoid organs (except in the spleen) and an increase in the muscles of diabetic rats compared with the control group. All these changes found in diabetic rats were reversed by insulin treatment and were not modified by the normalization of glycaemia.
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PMID:Superoxide dismutase, catalase and glutathione peroxidase activities in the lymphoid organs of diabetic rats. 796 75

Transcriptional regulation of the sodA gene, a member of the soxRS regulon encoding the manganese-containing superoxide dismutase (MnSOD; superoxide:superoxide oxidoreductase, EC 1.15.1.1) of Escherichia coli, was examined in a variety of regulatory mutants. Diamide, an oxidant that causes the anaerobic biosynthesis of the MnSOD polypeptide and also facilitates insertion of manganese at the active site, was found to anaerobically induce MnSOD in both soxRS and fur arcA fnr strains. Metal chelating agents also caused anaerobic induction of MnSOD in a fur arcA fnr triple mutant; however, this induction of MnSOD and of glucose-6-phosphate dehydrogenase (G6PD) by 1,10-phenanthroline was dependent on an intact soxRS locus. A strain of E. coli bearing a fusion of the soxS promoter to lacZ was used to demonstrate that both diamide and 1,10-phenanthroline caused anaerobic activation of soxS transcription. These results indicate that (i) both diamide and 1,10-phenanthroline induce the soxRS regulon anaerobically by stimulation of soxS transcription; (ii) diamide, but not metal chelators, also induces MnSOD biosynthesis by a soxRS-independent mechanism, perhaps mediated by effects on fur, arcA, or fnr-mediated repression of sodA; and (iii) the soxRS locus contains a metal-binding component and is responsive to the redox status of the cell.
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PMID:Induction of manganese-containing superoxide dismutase in anaerobic Escherichia coli by diamide and 1,10-phenanthroline: sites of transcriptional regulation. 846 Jan 39

Thiobarbituric acid reactant substances (TBARs) content, and the activities of glucose-6-phosphate dehydrogenase (G6PDh), citrate synthase (CS), Cu/Zn- and Mn-superoxide dismutase (SOD), catalase, and glutathione peroxidase (GPX) were measured in the lymphoid organs (thymus, spleen, and mesenteric lymph nodes (MLN)) and skeletal muscles (gastrocnemius and soleus) of adrenodemedullated (ADM) rats. The results were compared with those obtained for sham-operated rats. TBARs content was reduced by adrenodemedullation in the lymphoid organs (MLN) (28%), thymus (40%) and spleen (42%)) and gastrocnemius muscle (67%). G6PDh activity was enhanced in the MLN (69%) and reduced in the spleen (28%) and soleus muscle (75%). CS activity was reduced in all tissues (MLN (75%), spleen (71%), gastrocnemius (61%) and soleus (43%)), except in the thymus which displayed an increment of 56%. Cu/Zn-SOD activity was increased in the MLN (126%), thymus (223%), spleen (80%) and gastrocnemius muscle (360%) and was reduced in the soleus muscle (31%). Mn-SOD activity was decreased in the MLN (67%) and spleen (26%) and increased in the thymus (142%), whereas catalase activity was reduced in the MLN (76%), thymus (54%) and soleus muscle (47%). It is particularly noteworthy that in ADM rats the activity of glutathione peroxidase was not detectable by the method used. These data are consistent with the possibility that epinephrine might play a role in the oxidative stress of the lymphoid organs. Whether this fact represents an important mechanism for the establishment of impaired immune function during stress remains to be elucidated.
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PMID:Changes in the TBARs content and superoxide dismutase, catalase and glutathione peroxidase activities in the lymphoid organs and skeletal muscles of adrenodemedullated rats. 969 30


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