Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:P04040 (Catalase)
 3,577 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Oxygen free radicals are known to form after reperfusion of ischemic tissue. To test the role and importance of oxygen free radicals in hemorrhagic shock, an animal model of hemorrhagic shock and resuscitation was utilized. Sprague-Dawley rats were anesthetized with halothane and then subjected to approximately 50 per cent blood volume hemorrhage (30 cc/kg), followed by a 60 min shock period. Resuscitation was performed over 1 hour with lactated ringers (LR) at a volume of two times blood loss (60 cc/kg). This model results in a survival rate of 25 per cent over 72 hrs. Using this model, animals were randomized to receive either LR, Superoxide Dismutase-Polyethylene Glycol (SOD-PEG) (15,000 units/kg) with LR or Catalase-Polyethylene Glycol (CAT-PEG) (175,000 units/kg) with LR. The group treated with SOD-PEG demonstrated significantly increased survival rates vs the group treated with LR (67% vs 25%, P = 0.02). The group treated with CAT-PEG demonstrated no significant improvement in survival when compared to the LR-treated group (20% vs 24%). These data suggest that treatment directed toward oxygen free radicals and reperfusion injury may play an important role in hemorrhagic shock resuscitation.
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PMID:Superoxide dismutase polyethylene glycol improves survival in hemorrhagic shock. 174 87

Two isozymes of catalase (EC 1.11.1.6), one with typically low peroxidatic activity (CAT-1) and the other with enhanced-peroxidatic activity (EP-CAT or CAT-3) have been purified to electrophoretic homogeneity from tobacco (Nicotiana sylvestris) seedlings and antibodies prepared against each. The isozyme proteins showed no immunological cross-reactivity. The subunit Mr was 55,300 +/- 750 for CAT-1 and 53,300 +/- 850 for CAT-3 as determined by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. In the catalatic reaction, the apparent Km values for CAT-1 and CAT-3 were 0.057 and 0.054 M, respectively, and the kcat values were 4.8 x 10(7) and 3.0 x 10(6) min-1, respectively. In the peroxidatic reaction, both have similar apparent Km's for H2O2. The apparent Km values for CAT-3 for the series methyl, ethyl, propyl, butyl, and allyl alcohols were 2.48, 5.6, 38.6, 429, and 16.3 mM, respectively. For CAT-1, the values were 697, 55.8, no detectable reaction with propyl and butyl, and 163 mM, respectively. Neither isozyme utilized dianisidine or guaiacol in the peroxidatic reaction. Catalase activity (CAT-2) which eluted in an intermediate position between CAT-1 and CAT-3 from a chromatofocusing column was composed of only one subunit whose Mr coincided with CAT-1, and only the antibody to CAT-1 reacted with CAT-2 protein. Thus, CAT-2 and CAT-1 appear closely related while CAT-3 is distinctly different.
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PMID:Purification and characterization of an isozyme of catalase with enhanced-peroxidatic activity from leaves of Nicotiana sylvestris. 227 60

EDTA-chelated ferrous chloride (Fe(2+)-EDTA) mixed with ascorbic acid (VC) was shown in vitro to produce 2,3-dihydroxybenzoic acid (2,3-DHBA), one of the hydroxyl radical (.OH) derivatives formed from reaction with 1 mM salicylic acid. The .OH generating system of Fe(2+)-EDTA (5, 25 and 50 microM) mixed with VC (50, 250 and 500 microM) was perfused for 15 min to the isolated rat hearts to characterize the effect of exogenous .OH on cardiac function, metabolism, and structure. A dose-effect relationship was observed between .OH dosage and ventricular dysfunction, increase in coronary flow, structural damage, decrease in ATP and increase in lipid peroxidation. Catalase (CAT, 500 U/ml) and deferoxamine (DFX, 10 mM) significantly (P < 0.05) reduced .OH formation in vitro, but superoxide dismutase (SOD, 100 U/ml) did not. When these agents were given to the heart perfused with 50 microM Fe(2+)-EDTA plus 500 microM VC, SOD failed to modify any myocardial alterations whereas CAT and DFX completely reversed them. Addition of 500 microM hydrogen peroxide (H2O2) to the 50 microM Fe(2+)-EDTA plus 500 microM VC further caused a 14-fold increase in .OH generation. Addition of H2O2 (500 microM) to the .OH generating mixture induced more conspicuous myocardial changes compared with the mixture without H2O2 addition, but the extent of those changes other than increase in coronary flow was less than that caused by perfusion with 500 microM H2O2 alone. These results further suggest that the cardiac changes induced by the .OH generating system are due to the combined effects of .OH and H2O2 which is formed as an intermediate product.
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PMID:Characterization of exogenous hydroxyl radical effects on myocardial function, metabolism and ultrastructure. 807 2

Catalase (EC 1.11.1.6) isoforms CAT 2 through CAT 8 were purified from peroxisomes of sunflower (Helianthus annuus L.) cotyledons and photoinactivated in vitro. Action and absorbance spectra between 380 and 727 nm wavelength showed most prominent maxima at 405 nm suggesting an inactivation mediated by light absorption of heme groups. First order kinetics of inactivation were observed for CAT 6 through CAT 8 (isoform group B), which are composed of four 55-kDa subunits. Inactivation constants ki depended on photon fluence rates in the studied range between 8.3 and 660 microE m(-2) s(-1). The maximal value of ki was about 4.0 h(-1), corresponding to a half-life of about 10 min. Heme groups and 55-kDa apoprotein moieties of group B isoforms were degraded during irradiation, but both degradation processes occurred at rates lower than those of inactivation. Quantitative evaluations contradicted the view that photoinactivation was caused by destruction or dissociation of heme but suggested apoprotein damage leading to the loss of activity. Group A isoforms CAT 2 through CAT 5, containing both 55- and 59-kDa subunits, were less photosensitive than the isoforms of group B. In addition, irradiated group A isoforms reached a low plateau of residual activity, whereas group B isoforms were inactivated completely. The 59-kDa subunits in group A isoforms were much more resistant to photodegradation than the 55-kDa subunits of group B isoforms and also much more resistant than their own 55-kDa cosubunits. Results presented here are compared with catalase photoinactivation and turnover in vivo and discussed with respect to a physiological significance of catalase isoforms in plant peroxisomes.
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PMID:In vitro photoinactivation of catalase isoforms from cotyledons of sunflower (Helianthus annuus L.). 934 68

Catalase gene expression was characterized in the scutellum of maize seedlings grown at normal (25 degrees C) and elevated temperatures (35 and 40 degrees C). Chronic elevated temperatures reduce scutellar catalase activity most noticeably in the inbred lines W64A and R6-67, which express all three CAT isozymes (CAT-1, CAT-2, and CAT-3). The observed decline in catalase activity is primarily attributed to a decrease in the amount of CAT-2 isozyme, due to diminished levels of the Cat2 transcript. As CAT-2 activity levels are regulated by the trans-acting gene locus Car1, it is possible that the Car1 gene product is inhibited at the elevated temperatures. In maize lines null for CAT-2 or both CAT-2 and CAT-3, the relative levels of Cat1 transcript, although steady throughout the 10 days post-imbibition scutellar profile, are slightly higher with increasing temperatures. This might indicate that, in thermally stressed seedlings, the accumulation and/or stability of Cat1 mRNA might compensate for the lack of Cat2 transcript in a tissue where Cat2 mRNA normally accumulates during the developmental period examined. These observations, along with the drastic reduction in seed germination and seedling height at chronically elevated growth temperatures, suggest that developmental arrest, rather than oxidative stress, might be the cause for the observed results relative to Cat gene expression under such conditions.
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PMID:Catalase gene expression in response to chronic high temperature stress in maize. 1090 10

The effects of exposure to different concentrations of phenoxyherbicides and their metabolites were studied in human erythrocytes, with particular attention to catalase (CAT-EC. 1.11.1. 6- hydrogen peroxide: hydrogen peroxide oxidoreductase). 4-chloro-2-methylphenoxyacetic acid (MCPA), 2,4-dimethylphenol (2, 4-DMP) and 2,4-dichlorophenoxyacetic acid (2,4-D) did not affect CAT activity, but 2,4-dichlorophenol (2,4-DCP) and 2,4,5-trichlorophenol (2,4,5-TCP) decrease its activity, the latter being the more inhibitory.
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PMID:Catalase activity in human erythrocytes: effect of phenoxyherbicides and their metabolites. 1102 48

Catalase (CAT, EC 1.11.1.6) activity was measured in flesh tissue of six apple cultivars (Malus domestica Borkh. cvs. Braeburn, Gala, Jonagold, McIntosh, Red Delicious, and Spartan). Activity of CAT was determined for fresh and frozen tissue of the same fruit. Freezing resulted in reductions of 50 to 90% in CAT activity compared with the activity measured in crude extracts from fresh tissues. The rate of freezing had an impact on the level of reduction of CAT activity, with slower freezing procedures leading to greater losses in activity. Six additives to the extraction buffer were tested to evaluate their potential to reduce the inactivation of CAT from frozen tissue, but only EDTA and Tween 20 showed any benefit. However, EDTA and Tween 20 provided only partial recovery in CAT activity. In contrast, crude extracts prepared from fresh tissue showed no appreciable loss in CAT activity after frozen storage for two weeks at -80 degrees C. Gel electrophoresis and immunological analysis indicated that the loss in CAT activity from tissue freezing could be attributed to loss of both the tetrameric CAT enzyme structure and total CAT protein. The implications of using freezing to preserve apple tissue samples prior to catalase activity analysis is discussed.
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PMID:Effect of freezing on the activity of catalase in apple flesh tissue. 1108 15

Bed rest is an integral part of treatment of numerous diseases. Typical examples are bone fractures of lower extremities and pelvis. Temporary immobilization is necessary also, e.g., in heart diseases (stroke), backbone and imminent abortion. The sick organism spares energy during the bed rest wich is beneficial. However, bed rest results in many alterations which are disadavantageous. They concern the function of almost all organs and systems but affect most significantly the locomotor and ciruclatory systems. Bed rest brings also about changes in the composition of peripheral blood and functions of the morphotic elements of blood. Red blood cells are subjected to the action of large amounts of reactive oxygen species (ROS). During oxidation of hemoglobin to methemoglobin superoxide radical anion (O2-) is formed: HbFe2+ + O2 --> MetHbFe3+ + O2- (1) Ferrous and ferric ions present in the cytoplasm of red blood cells may be catalysts of the Fenton reaction leading to the production of the hydroxyl radical: O2- + Fe3+ --> O2- + Fe2+ (2) Fe2+ + H2O2 --> Fe3+ + OH + HO- (3) OH shows a tremendous reactivity. It may react with lipids, proteins, nucleic acids and carbohydrates. The process of lipid peroxidation is best understood. It concerns mainly polyunsaturated fatty acids present in cell membranes. Peroxidation of membrane lipids decreases membrane fluidity and impairs its barrier function. The lowered membrane fluidity compromises erythrocyte deormability which in turn disturbs oxygen delivery to the tissues. End productions of lipid peroxidation are low-molecular wieght compounds, among them carbohydrates (ethane and pentane) and aldehydes, e.g. malondialdehyde (MDA). MDA concentration is an acknowldeged marker of the intensity of lipid peroxidation. Erythrocytes contain a complex system of protection against the action of ROS. It includes various enzymatic and non-enzymatic mechanism. The most important antioxidative enzymes of the red blood cells are superoxide dismutase (Cu,Zn-SOD, EC 1.15.1.1) catalase (CAT, EC 1.11.1.6) and glutathione peroxidase (GSH-Px, EC 1.11.1.9). Cu,Zn-SOD catalyzes the dismuation of O2- to hydrogen peroxide (H2O2). Catalase and peroxidase remove H2O2 and, moreover, GSH-Px can reduce lipid peroxides. Under normal conditions an equilibrium exists between the formation and removal ROS. If ROS are formed in excess or the defensive antioxidative mechanism are inefficient, oxidative stress develops. Derangement of the equilibrium between the formation and removal of ROS is important in the pathosgenesis of many diseases, e.g. atherosclerosis, diabetes, Down syndrome and Alzheimer disease. There are literature data on disturbances of enzymatic antioxidant defense mechanism of blood plateless during bed rest. This study was aimed at an examination of the post-traumatic bed rest on the enzymatic antioxidative defense mechanisms and lipid peroxidation in erythrocytes.
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PMID:Effect of long term bed rest in men on enzymatic antioxidative defence and lipid peroxidation in erythrocytes. 1154 39

Antimutagens and anticarcinogens are known to play an important role in decreasing damages induced by oxidants. In this study, we investigated the genotoxic and antimutagenic potential of two selenium compounds (sodium selenite: Na(2)SeO(3); seleno-DL-methionine: C(5)H(11)NO(2)Se) and Vitamins A and E in yeast cells of Saccharomyces cerevisiae. An oxidative mutagen (hydrogen peroxide (H(2)O(2)), HP) was chosen as positive control. We determined the enzymatic activities involved in the protection against oxidative damages (catalase: CAT; superoxide dismutase: SOD; glutathione peroxidase: GPx) in the cytosolic extract of yeast cells. The results demonstrated that selenium compounds exerted both mutagenic and antimutagenic effect at different concentrations. Antimutagenesis was evident both in stationary and in logarithmic phase cells. Catalase, SOD, and GPx were significantly increased in the presence of all the compounds assayed. Vitamins A (retinol) and E (alpha-tocopherol) did not have toxic or mutagenic action.
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PMID:Protective effects of vitamins and selenium compounds in yeast. 1155 86

Cucumber seedling radicles become more chilling sensitive as they elongate. Chilling seedlings with radicles 20 mm long for 48 h at 2.5 degrees C inhibited subsequent growth by 36%, while it reduced the growth of 70 mm-long radicles by 63%. Although the growth rate of non-chilled cucumber radicles at 25 degrees C is constant from 20 to 80 mm, tissue viability [i.e. reduction of TTC (2,3,5-triphenyltetrazolium chloride) to formazan] and DPPH (alpha,alpha-diphenyl-beta-picrylhydrazyl) radical scavenging activity of apical tissue declines as radicles elongate from 20 to 80 mm in length. TTC reduction, DPPH-radical scavenging activity and protein content of apical tissue were higher in 20 than in 70 mm radicles immediately after chilling and after an additional 48 h of growth at 25 degrees C. Catalase (CAT; EC 1.11.1.6) and ascorbate peroxidase (APX; EC 1.11.1.11) activity was higher in the apical tissue of 20 than in 70 mm radicles before chilling. Immediately after chilling and after an additional 48 h at 25 degrees C, superoxide dismutase (SOD; EC 1.15.1.1), glutathione reductase (GR; EC 1.6.4.2), and guaiacol peroxidase (GPX; EC 1.11.1.7) activity increased more rapidly in 70 mm radicles than in 20 mm radicles (SOD, GR, and GPX activity in 70 mm radicles was 1.5-, 1.9- and 8.6-fold higher, respectively, than in 20 mm radicles). However, APX and CAT activity in 20 mm radicles were always higher than in 70 mm radicles. Growth after chilling enhanced the activity of all antioxidant enzymes compared to that found in non-chilled tissue; however, CAT activity in 70 mm radicles did not recover to levels found in non-chilled tissue. Higher levels of CAT, APX and DPPH-radical scavenging activity are correlated with higher chilling tolerance of 20 mm-long cucumber radicles compared to 70 mm-long radicles.
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PMID:Reduced chilling tolerance in elongating cucumber seedling radicles is related to their reduced antioxidant enzyme and DPPH-radical scavenging activity. 1206 Feb 42


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