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The human promyelocytic leukemia cell line HL-60 undergoes induced myeloid differentiation, with acquisition of most polymorphonuclear leukocyte (PMN) functions, including generation of toxic oxygen species. We examined the concurrent changes in the cellular detoxifying defenses against superoxide and H2O2: superoxide dismutase, catalase, and the glutathione cycle. During induced differentiation, total superoxide dismutase activity declined to a level slightly more than 2-fold that of PMN, largely due to a decrease in Mn-superoxide dismutase; CuZn-superoxide dismutase showed virtually no change. Catalase activity declined only slightly (but significantly) to a level 1.3 that of PMN. GSH peroxidase activity fell and then rose back to its original level, remaining throughout differentiation more than 10-fold higher than activity in PMN. GSSG reductase activity declined to a level of 73% that of uninduced cells but twice that of PMN. GSH and GSSG contents both decreased, reaching equivalence to those of PMN. Concurrently, the ability of the cells to generate H2O2 increased 11-fold, a change similar to that previously reported for superoxide production. Thus, there is a paradoxical inverse relationship between the development of active oxygen generation and scavenging systems during myeloid differentiation in HL-60 cells.  相似文献   

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For preparationing the polyenzyme antioxidant complex, containing superoxide dismutase (SOD), catalase and horseradish peroxidase (HRP), the different successivities of those enzymes co-immobilization were compared. The optimum successivity is provided by simultaneous co-immobilization of covalently bound HRP with the SOD and catalase. The catalytic enzyme activity and the catalase operational stability was kinetically characterized in various samples. For one sample, the influence of ascorbate, glutathione and ethanol on the catalase kinetic parameters was studied. A possible scheme of different processes at the H2O2 decomposition in the presence of co-immobilized SOD, catalase, HRP and the substrates-reductans was discussed.  相似文献   

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The effect of genetically determined glutathione deficiency on the fibroblast content of CuZn superoxide dismutase, Mn superoxide dismutase, catalase and glutathione peroxidase was investigated. No significant differences between glutathione-deficient and -proficient human fibroblasts were revealed. There was a large variation in the content of the investigated enzymes in fibroblasts grown and analysed on different occasions. Whereas the contents of CuZn superoxide dismutase, catalase and glutathione peroxidase did not deviate much from what has been found in other human cell-lines and tissues, the fibroblasts were found to contain exceptional amounts of Mn superoxide dismutase.  相似文献   

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The effects of superoxide dismutase (SOD) and catalase on the autoxidation rate of L-ascorbic acid (ASA) in the absence of metal ion catalysts were examined. The stabilization of ASA by SOD was confirmed, and the enzyme activity of SOD, which scavenges the superoxide anion formed during the autoxidation of ASA, contributed strongly to this stabilization. The stabilization of ASA by catalase was observed for the first time; however, the specific enzyme ability of catalase would not have been involved in the stabilization of ASA. Such proteins as bovine serum albumin (BSA) and ovalbumin also inhibited the autoxidation of ASA, therefore it seems that non-specific interaction between ASA and such proteins as catalase and BSA might stabilize ASA and that the non-enzymatic superoxide anion scavenging ability of proteins might be involved.  相似文献   

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Abstract:  Superoxide dismutase and catalase activity was found in the bird cherry-oat aphid, Rhopalosiphum padi (L.) and the grain aphid, Sitobion avenae (F.). Among the aphid morphs studied, the highest activity of the antioxidant enzymes was noted for winged adults (alatae) and the lowest for wingless (apterae) ones. Higher activity of superoxide dismutase and catalase was observed in the polyphagous species R. padi that alternates between woody host plants and grasses. On some ocassions, activity of superoxide dismutase in cereal aphids was increased by twofold, when aphids were exposed to toxic plant o -dihydroxyphenols. An opposite tendency was observed in case of activity of the catalase that was strongly reduced within body of phenolics-treated insects. Among the plant allelochemicals studied, caffeic acid showed the strongest effect on the activity of the antioxidant enzymes of the cereal aphids. The experiments carried out indicate that antioxidant enzymes might play an important role in interactions between cereal aphids and their host plants.  相似文献   

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A. Puppo  L. Dimitrijevic  J. Rigaud 《Planta》1982,156(4):374-379
Superoxide anion is able to oxidize oxyleghemoglobin prepared from soybean nodules. Furthermore, ferrileghemoglobin is oxidized to leghemoglobin (IV) by hydrogen peroxide and this irreversible reaction leads to a complete inactivation of the hemoprotein. In scavenging O 2 - and H2O2, superoxide dismutase (EC 1.15.1.1) and catalase (EC 1.11.1.6) are able to limit these oxidations. The occurrence of these enzymes within soybean nodules and their main characteristics are reported here. A general scheme taking into account their roles in leghemoglobin protection in vivo is proposed.Abbreviations Lb leghemoglobin - SOD superoxide dismutase  相似文献   

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Embryonic bioactivation and formation of reactive oxygen species (ROS) are implicated in the mechanism of phenytoin teratogenicity. This in vivo study in pregnant CD-1 mice evaluated whether maternal administration of the antioxidative enzymes superoxide dismutase (SOD) and/or catalase conjugated with polyethylene glycol (PEG) could reduce phenytoin teratogenicity. Initial studies showed that pretreatment with PEG-SOD alone (0.5–20 KU/kg IP 4 or 8 h before phenytoin) actually increased the teratogenicity of phenytoin (65 mg/kg IP on gestational days [GD] 11 and 12, or 12 and 13) (p < .05), and appeared to increase embryonic protein oxidation. Combined pretreatment with PEG-SOD and PEG-catalase (10 KU/kg 8 or 12 h before phenytoin) was not embryo-protective, nor was PEG-catalase alone, although PEG-catalase alone reduced phenytoin-initiated protein oxidation in maternal liver (p < .05). However, time-response studies with PEG-catalase (10 KU/kg) on GDs 11, or 11 and 12, showed maximal 50-100% increases in embryonic activity sustained for 8-24 h after maternal injection (p < .05), and dose-response studies (10–50 KU/kg) at 8 h showed maximal respective 4-fold and 2-fold increases in maternal and embryonic activities with a 50 KU/kg dose (p < .05). In controls, embryonic catalase activity was about 4% of that in maternal liver, although with catalase treatment, enhanced embryonic activity was about 2% of enhanced maternal activity (p < .05). PEG-catalase pretreatment (10-50 KU/kg 8 h before phenytoin) also produced a dose-dependent inhibition of phenytoin teratogenicity, with maximal decreases in fetal cleft palates, resorptions and postpartum lethality at a 50 KU/kg dose (p < .05). This is the first evidence that maternal administration of PEG-catalase can substantially enhance embryonic activity, and that in vivo phenytoin teratogenicity can be modulated by antioxidative enzymes. Both the SOD-mediated enhancement of phenytoin teratogenicity, and the inhibition of phenytoin teratogenicity by catalase, indicate a critical role for ROS in the teratologic mechanism, and the teratologic importance of antioxidative balance.  相似文献   

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AIMS: Staphylococcus carnosus, used as starter culture in fermented meat products, decreases the level of volatiles arising from lipid oxidation. To analyse its antioxidant capacities, catalase and superoxide dismutase (SOD) were characterized. METHODS AND RESULTS: Catalase and SOD activities were measured with spectrophotometric methods and visualized on non-denaturing polyacrylamide gels. The corresponding sod gene was identified by PCR. Southern hybridizations and enzymatic analyses showed that there was a single catalase and a single SOD in Staph. carnosus 833 strain. The gene encoding the Staph. carnosus SOD was found to encode a protein closely related to SOD requiring manganese. Catalase and SOD levels increased in mid-log phase. Only catalase was induced by oxygen, nitrate or nitrite while glucose induced neither enzyme. Metal ion limitation increased catalase and decreased SOD activities. CONCLUSION: Staph. carnosus synthesizes both enzymes in conditions encountered in sausage manufacturing. These results could explain the antioxidant properties of Staph. carnosus starter culture. SIGNIFICANCE AND IMPACT OF THE STUDY: The knowledge of the antioxidant properties of Staphylococci will allow a more rational use of these starters in meat fermented products.  相似文献   

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Abstract The planktonic cyanobacterium Microcystis aeruginosa is particularly sensitive to photoinhibition by visible light, Photosystem II and ribulose 1,5-bisphosphate (RuBP) carboxylase activities being affected. Although the organism contains superoxide dismutase (SOD) and catalase, these protective enzymes are also photoinactivated during the illumination of whole cells by visible light.  相似文献   

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Superoxide dismutase/catalase mimetics, such as salen Mn complexes and certain metalloporphyrins, catalytically neutralize reactive oxygen and nitrogen species, which have been implicated in the pathogenesis of many serious diseases. Both classes of mimetic are protective in animal models of oxidative stress. However, only AEOL11207 and EUK-418, two uncharged Mn porphyrins, have been shown to be orally bioavailable. In this study, EUK-418 and several new analogs (the EUK-400 series) were synthesized and shown to exhibit superoxide dismutase, catalase, and peroxidase activities in vitro. Some also protected PC12 cells against staurosporine-induced cell death. All EUK-400 compounds were stable in simulated gastric fluid, and most were substantially more lipophilic than the salen Mn complexes EUK-189 and EUK-207, which lack oral activity. Pharmacokinetics studies demonstrate the presence of all EUK-400 series compounds in the plasma of rats after oral administration. These EUK-400 series compounds are potential oral therapeutic agents for cellular damage caused by oxidative stress. Electronic supplementary material  The online version of this article (doi:) contains supplementary material, which is available to authorized users.  相似文献   

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Jeon B  Kim BH  Lee YS  Kim S  Yoon JB  Kim TY 《BMB reports》2011,44(1):40-45
Extracellular superoxide dismutase (EC-SOD) is an antioxidant enzyme that protects cells and tissues from extracellular damage by eliminating superoxide anion radicals produced during metabolism. Two different forms of EC-SOD exist, and their different enzyme activities are a result of different disulfide bond patterns. Although only two folding variants have been discovered so far, five folding variants are theoretically possible. Therefore, we constructed five different mutant EC-SOD expression vectors by substituting cysteine residues with serine residues and evaluated their expression levels and enzyme activities. The mutant EC-SODs were expressed at lower levels than that of wild-type EC-SOD, and all of the mutants exhibited inhibited extracellular secretion, except for C195S ECSOD. Finally, we demonstrated that co-expression of wild-type EC-SOD and any one of the mutant EC-SODs resulted in reduced secretion of wild-type EC-SOD. We speculate that mutant EC-SOD causes malfunctions in systems such as antioxidant systems and sensitizes tissues to ROS-mediated diseases.  相似文献   

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Summary The effects of oxygen (100%), paraquat (0.5 mM), and copper (0.1 mM) on the growth and the biosynthesis of the antioxidant enzymes, superoxide dismutase (SOD) and catalase, were studied in Saccharomyces cerevisiae grown in glucose-limited chemostat cultures. The effect of dilution rates (D, h−1) on cell mass, glucose consumption, ethanol production, oxygen uptake, and specific activities of SOD and catalase were also investigated at each steady state. SOD was optimally produced at D-values between 0.22 and 0.26 h−1 in the presence of oxygen or paraquat, and at D-values greater than 0.17 h−1 when copper was used. On the other hand, catalase activity decreased with increasing D-values. However, the presence of copper or 100% oxygen repressed catalase activity at low D-values (D<0.1 h−1), and decreased the rate of oxygen uptake at all D-values tested. The presence of paraquat affected the rate of oxygen uptake only at high D-values (D>0.22 h−1). We also studied the effect of oxygen concentration on the biosynthesis of SOD and catalase at D=0.1 h−1. The data clearly show that synthesis of SOD and catalase, though correlated with changes in oxygen tension, are independent of one another. Paper Number 10871 of the Journal Series of North Carolina Agricultural Research Service, Raleigh, NC 27 695. The use of trade names in this publication does not imply endorsement by the North Carolina Agricultural Research Service of the products named, nor criticism of similar ones not mentioned  相似文献   

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The use of high oxygen concentrations and high mean airway pressures during mechanical ventilation of premature newborn infants with respiratory distress syndrome leads in 20%–30% of the survivors to chronic lung disease. This study explores if exogenous polyethylene glycol conjugated superoxide dismutase (PEG-SOD) and catalase (PEG-CAT) mitigate oxygen toxicity in premature lambs with respiratory distress syndrome. Six pairs of premature lambs were delivered by cesarean section and treated by tracheal instillation of 60 mg natural sheep surfactant/kg/body weight. After birth, all lambs were ventilated with 100% oxygen, and one of each pair received a single intravenous injection of 1 million U/kg PEG-CAT and 50,000 U/kg PEG-SOD. At 8 h of age or after respiratory failure was established, the lambs were killed and the lungs were removed intact. Lung damage was assessed by microscopy. The arterial blood gases, pH, and mean airway pressures of the lambs treated with PEG-SOD/PEG-CAT did not differ from those of the controls. Mean PaO2 was > 140 mmHg during the first 4 h of the experiments. In the lambs treated with PEG-SOD/PEG-CAT, SOD and CAT levels were very high during the study period and less bronchiolar epithelial damage and lung hemorrhages were found at microscopy.  相似文献   

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Mimetics of antioxidant enzymes such as superoxide dismutases (SOD) or catalases are reported as potential new drugs able to reduce oxidative stress damage. In particular, manganese(III) complexes of salen-type ligands have been studied as both SOD and catalase mimetics. In this paper, we report the synthesis of two novel conjugates of salen-type ligands with the β-cyclodextrin, the 6-deoxy-6-[(S-cysteamidopropyl(1,2-diamino)N,N′-bis(salicylidene))]-β-cyclodextrin and the 6-deoxy-6-[(S-cysteamidopropyl(1,2-diamino)N,N′-bis(3-methoxysalicylidene))]-β-cyclodextrin, their spectroscopic characterization, and the synthesis and the characterization of their manganese(III) complexes. The SOD-like activity of the metal complexes was investigated by the indirect Fridovich method. The catalase like activity was tested using a Clark-type oxygen electrode. The peroxidase activity was tested using the ABTS (2,2′-azino-bis-(3-ethylbenzothiazoline-6-sulfonic acid)) assay. The glycoconjugation of salen-manganese(III) complexes yields compounds with enhanced SOD activity. These complexes also show catalase and peroxidase activities higher than the simple salen complexes (EUK 113 and EUK 108).  相似文献   

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Free radical-mediated damages may play an important role in cancerogenesis. To investigate their relevance in the cancer process, malonyl dialdehyde (MDA) level, superoxide dismutase (SOD), and catalase (CAT) activities were determined in the normal brain tissue and brain tumor tissue. When compared with the normal brain tissue, we have detected: (i) significantly lower MDA concentration in brain tumor tissue (1.63 nmol/mg Pr vs 2.04 nmol/mg Pr; p = 0.03); (ii) SOD activity in brain tumor tissue was significantly lower (3.15 U/mg Pr vs 4.97 U/mg Pr; p = 0.0002); and (iii) CAT activity in brain tumor tissue was 106.3% higher than that in controls.  相似文献   

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