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Query: UNIPROT:P04040 (Catalase)
 3,577 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The objective of this study was to determine whether aging in the housefly is associated with a general decline in the efficiency of the mechanisms protective against the intermediates of oxygen metabolism. The rate of oxygen consumption, activities of superoxide dismutase (total and cyanide-insensitive) and catalase, and levels of inorganic peroxides, glutathione (GSH and GSSG) and chloroform-soluble antioxidants were measured in adult male houseflies at different ages. Rate of oxygen consumption declined in flies approaching the average life span of the population. Activity of total and cyanide-insensitive superoxide dismutase decreased during the last trimester of life. Catalase activity steadily declined with age while the concentration of inorganic peroxides gradually increased during the later two-thirds of the average life span. Levels of total glutathione and GSH decreased during later half of life whereas the relative concentration of GSSG increased during this period. The concentration of chloroform-soluble antioxidants sharply declined during the first half of life. These results are interpreted to suggest that the enzymatic and non-enzymatic defenses against oxygen free radicals and hydroperoxides tend to deteriorate with age in the adult housefly.
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PMID:Effect of age on oxygen consumption, superoxide dismutase, catalase, glutathione, inorganic peroxides and chloroform-soluble antioxidants in the adult male housefly, Musca domestica. 671 88

The concentration of lipid peroxidation was extensively high in rat fetuses and early newborns. However, it declined sharply thereafter. Superoxide dismutase (SOD) activity was approximately 10% of the adult level during 5 days postpartum. The enzyme activity began to increase after the 10th day to 60% of the adult level at the 20th day. Catalase activity was low in the fetal period, corresponding to approximately 20% of the adult level, but increased rapidly after birth reaching approximately 50% of the adult level at 5-7 days postpartum. Glutathione peroxidase (GSH-Px) activity was measured to amount to only 7% of the adult level in the fetal and early newborn period. The level of this activity was approximately 20% of the adult level at the 20th day. The difference in GSH-Px activity became wide between sexes after the first 30 days of life; the male adult level was 61% of the female adult level. The concentration of vitamin E was low in the fetus. It increased by a factor of 10 times within a few days after birth, and thereafter it decreased gradually. Fetal and early newborn livers have low enzymatic defense capabilities against possible deleterious effects of lipid peroxidation processes.
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PMID:Lipid peroxidation and antioxidants in rat liver during development. 712 40

Glutathione peroxidase (GSH-Px) and catalase activities were evaluated during intake of excess dietary iron. Male Sprague-Dawley rats were randomized into seven dietary treatments. The treatments included three levels of dietary iron (35, 305, and 1255 ppm) plus deficiencies of Se or Se and vitamin E at the two high iron levels. Lipid peroxidation in liver and GSH-Px and catalase activities in erythrocytes and liver were measured. Lipid peroxidation was elevated in all high iron groups compared to controls. Total GSH-Px in erythrocytes and liver remained constant or decreased in animals receiving high iron, but non Se GSH-Px increased significantly in liver from rats fed high iron (305 ppm: 155% and 1255 ppm: 131%) and increased additionally in Se and vitamin E deficient groups. No differences in RBC catalase activity were observed. Liver catalase activity increased at least 72% during deficiencies of Se and vitamin E. In summary, GSH-Px did not respond to increased oxidative stress associated with elevated dietary iron except for the non Se GSH-Px which accounts for a relatively small amount of total activity in liver. Catalase increased in liver only when GSH-Px and vitamin E are limiting.
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PMID:Response of glutathione peroxidase and catalase to excess dietary iron in rats. 731 May 44

The extent of lipid peroxidation and the levels of its antioxidants such as superoxide dismutase (SOD), catalase and glutathione peroxidase (GSH-Px) were determined on lung tissues of the fetal, newborn and adult rat. Lipid peroxide formation was slight in the fetal period but augmented after birth reaching a peak at about 10 days after birth. The peroxide concentration then gradually declined with development and the adult level was found comparable to the fetal level. In the examination of the developmental defensive mechanism on the basis of assays for the aforementioned antioxidant enzymes in lung tissue, the SOD activity was low in fetuses reaching approximately 90% of the adult level at 10 days of life. Catalase was extremely low in concentration at all times, and age-related variations could not be definitely obtained. GSH-Px was also measured low in the fetal period and during 20 days after birth, but a subsequent gradual rise resulted in threefold greater activity in adults than in fetuses.
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PMID:Lipid peroxidation and antioxidants in the rat lung during development. 740 75

1. Mitochondrial H2O2 formation is not in equilibrium with defence mechanisms that counteract an accumulation of H2O2 in rat-heart cells. 2. A model for the accumulation kinetics is proposed which is consistent with the data presented. 3. Four different pathways of H2O2 metabolism are described in rat-heart mitochondria. The major site for metabolic branching of H2O2 via different routes was found to be the mitochondrial catalase. 4. Glutathione (GSH) peroxidase accounts for only 15% of intramitochondrial H2O2 metabolism, while catalase-mediated destruction is four times more rapid. 5. Catalase activity is limited by its structural compartmentation in the matrix, while GSH peroxidase activity was found to be dependent on the availability of free GSH. 6. Catalase was shown to protect rat-heart mitochondria from upsetting redox states of GSH and pyridine nucleotides following H2O2 decomposition by GSH peroxidase. 7. Computer simulations of experimental data suggest the existence of a third sink for mitochondrial H2O2, possibly due to mitochondrial formation of OH . radicals; another fraction of the H2O2 matrix pool may cross the mitochondrial membrane and accumulate in the cytosol.
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PMID:The metabolic fate of mitochondrial hydrogen peroxide. 743 85

Acetaminophen was given to mice at a single dose of 375 mg/kg. In situ liver chemiluminescence, H2O2 steady-state concentration, and the liver concentrations of total and oxidized glutathione were measured 15, 30, and 60 min after acetaminophen administration. Increases of 145% and 72% in spontaneous chemiluminescence and H2O2 concentration were observed 15 min after the injection, respectively. Total glutathione was decreased by acetaminophen administration at all the times studied. The maximal decrease, 83%, was found 60 min postinjection. The ratio GSH/GSSG was found significantly decreased at all the times studied. Microsomal superoxide production was increased by 2.4-fold by addition of acetaminophen. The activities of the antioxidant enzymes superoxide dismutase, catalase, and glutathione peroxidase were determined. Catalase was slightly inhibited (30%) 15 min after acetaminophen administration. No significant changes were found in superoxide dismutase activity. Se and non-Se glutathione peroxidase activities were decreased by 40% and 53% respectively, 15 min after acetaminophen administration. The decrease in catalase and glutathione peroxidase would result in an increased steady state level of H2O2 and hydroperoxides, contributing to cell injury. Damaged hepatocytes were observed, and severe lesions and necrosis appeared 60 min after acetaminophen administration. Our results indicate the occurrence of oxidative stress as a possible mechanism for acetaminophen-induced hepatotoxicity.
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PMID:Oxidative stress by acute acetaminophen administration in mouse liver. 755 44

Ferrihemoglobin formation by 4-(dimethylamino)phenol (DMAP), a potent cyanide antidote, is influenced by GSH under formation of various glutathione S-conjugates. Two of these were shown to be still reactive and able to produce ferrihemoglobin. The mechanism of ferrihemoglobin formation is fundamentally different from that found with the parent compound. First of all, induction periods of ferrihemoglobin formation were observed when 4-(dimethylamino)-2-(glutathion-S-yl)-phenol (2-GS-DMAP) and 4-(dimethylamino)-2,6-bis(glutathion-S-yl)phenol (2,6-bis-GS-DMAP) reacted with oxyhemoglobin at 100% and 20% oxygen, but not at 2% oxygen. This behavior points to thioether activation by autoxidation. Autoxidation proceeded in an autocatalytic manner, and the process was markedly modified by reducing agents, e.g., ferrihemoglobin and GSH, and by nucleophiles like GSH. Superoxide dismutase extended the lag phase of autoxidation and ferrihemoglobin formation. Catalase diminished markedly ferrihemoglobin formation, particularly at low oxygen pressure. The extent of this effect was much higher than expected if H2O2 had formed ferrihemoglobin directly. Conceivably, H2O2 might react with the thioethers or their oxidation products to give hitherto unidentified compounds of high catalytic activity in ferrihemoglobin formation. The results indicate that ferrihemoglobin formation by reactive glutathione conjugates of DMAP is essentially not a co-oxidation process as found with the parent DMAP and other aminophenols, but is mainly caused by an autocatalytic autoxidation process with formation of various reactive intermediates including superoxide radical anions and hydrogen peroxide. It appears that glutathione conjugation of autoxidizable aromatics does not necessarily lead to inactive phase II metabolites but opens new avenues of toxication reactions that may be a broader toxicological significance.
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PMID:Reactivity of glutathione adducts of 4-(dimethylamino)phenol. Involvement of reactive oxygen species during the interaction with oxyhemoglobin. 757 22

A comparison of the erythrocyte (RBC) antioxidant metabolites and enzymes in nine marsupial and two monotreme species was carried out. Reduced glutathione (GSH) concentrations were comparable with those reported for other marsupial and eutherian species. An important finding was that the erythrocytes of the southern hairy nosed wombat regenerated GSH faster than the erythrocytes from its close relative, the common wombat. The activities of glutathione-S-transferase, NADH-methaemoglobin reductase, superoxide dismutase, and glutathione peroxidase (GSH-Px), showed similar levels and extents of variation as those observed in other marsupial and eutherian species. Catalase activities in the marsupials were lower than those measured in the two monotreme species and much lower than those reported in eutherian species. A negative correlation, significant at P < 0.05, was observed between GSH-Px and catalase activities in the RBC of the marsupials. Since both these enzymes "detoxify" H2O2, there appears to be a reciprocal relationship between the activities of these enzymes in marsupial RBC.
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PMID:Comparative study of the antioxidant defence systems in the erythrocytes of Australian marsupials and monotremes. 759 75

Hyperplastic nodular cirrhosis was induced in rats by long-term (6 month) i.p. administration of thioacetamide at doses of 2.66 mmol/kg body wt, three times per week. The survival rate of animals at the end of the treatment was 90%. To follow the temporal changes samples at 0, 7, 15, 30, 45, 60, 90, 150 and 180 days from rats during thioacetamide intoxication and from chronological controls were obtained. The cirrhogenic ability of this treatment was assessed on the basis of morphological changes: the development of macronodular cirrhosis and the appearance of fibrous septa of collagen through portal spaces. Parameters of liver injury and cholestasis were obtained by assaying the serum activities of isocitrate dehydrogenase and gamma-glutamyltransferase. Enzymes and metabolites related to glutathione redox systems, as well as other antioxidant enzymes, were tested. Catalase and glutathione peroxidase, the two enzymes involved in the elimination of peroxides, and glutathione reductase decreased significantly at the end of the 6 months of intoxication, while Cu-Zn and Mn superoxide dismutases increased progressively during the long-term thioacetamide treatment. Protein thiol levels profile showed a biphasic change increasing from the 7th day and were insensitive to the 30% depletion of intracellular glutathione (GSH). To study the relationship of the intracellular thiols on the mechanisms of cell proliferation and differentiation during the cirrhogenic process, DNA content was assayed by flow cytometry in isolated hepatocytes, and DNA ploidy and distribution between G0-G1, S and G2 + M phases were determined. Remarkable changes in relation to a sharp increase in diploid population from 7 to 180 days (24.5%-->85.5%), a pronounced decrease in polyploid populations (tetraploid+octoploid) in the same period (73.7%-->12.3%), and elevations in the populations in S phase (S1 + S2) were observed in thioacetamide-treated rats. The results obtained indicate that hepatocytes isolated from thioacetamide-treated rats showed a marked tendency to diploidy, an enhancement in DNA replication parallel to the hepatic content of protein sulphydryl groups and a significant decline in antioxidant enzyme activities. The increase in protein thiols was independent of GSH level and of the thiol redox state.
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PMID:Relationship between antioxidant systems, intracellular thiols and DNA ploidy in liver of rats during experimental cirrhogenesis. 761 93

Antioxidative enzymes viz: glutathione peroxidase, glutathione reductase, catalase and aldehyde dehydrogenase were determined in the liver of rats treated with three industrial solvents viz: xylene, toluene and methyl alcohol both separately and in combination. Inhibited activity of glutathione peroxidase suggests reduction of hydroperoxides to corresponding alcohols. However, activity of glutathione reductase increased so as to maintain the glutathione (GSH) reserves. Catalase protected the rats by counteracting the superoxide radicals. However, inhibition of aldehyde dehydrogenase is attributed to the decreased availability of sulfahydryl groups. A trend to optimization of enzyme activities in the liver of co-treated rats suggests enhanced metabolism and excretion of xylene and toluene in the presence of methyl alcohol.
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PMID:Antioxidative enzyme in the liver of rats after exposure to xylene, toluene and methyl alcohol separately and in combination. 761 43


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