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)

Endogenous hydrogen peroxide (H2O2) release from aortic endothelial cells was studied in the presence of antioxidant enzyme inhibitors, mitochondrial inhibitors, a microsomal cytochrome P-450 inhibitor, and after oxidative stress induced with H2O2 or menadione. Extracellular H2O2 generation was determined spectrofluorometrically using 3-methoxy-4-hydroxy phenylacetic acid, and intracellular H2O2 production (in or near peroxisomes) was measured indirectly using aminotriazole, which inactivates catalase in the presence of H2O2. Extracellular H2O2 release was 0.079 +/- 0.005 nmol/min/mg protein in Hanks' balanced salt solution, was constant during a 120-min incubation period, and was not affected by the cell passage number. The half-life for catalase inactivation with aminotriazole was 23 min. Inhibition of catalase, glutathione reductase, or gamma-glutamylcysteine synthetase did not change the rate of extracellular release of H2O2. Furthermore, inhibition of the mitochondrial respiratory chain (rotenone, antimycin A) or microsomal cytochrome P-450 (8-methoxypsoralen) did not change extracellular H2O2 release or intracellular H2O2 production (at peroxisomes) by endothelial cells or cells in which glutathione reductase was inactivated. When the cells were exposed to exogenous H2O2 (30 microM), extracellular H2O2 was scavenged primarily by the glutathione redox pathway. Exogenously added H2O2 (100 microM) changed intracellular H2O2 production (in or near peroxisomes) only when the glutathione redox cycle was inactivated. Menadione (20 microM), which undergoes intracellular redox cycling, increased extracellular H2O2 release almost 4-fold to 0.3 nmol/min/mg protein. Furthermore, menadione increased peroxisomal H2O2 levels and decreased the half-life for catalase inactivation in the presence of aminotriazole to 13 min. Catalase inhibition increased extracellular H2O2 release during menadione treatment, indicating that H2O2 can diffuse across the plasma membrane during oxidant stress.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Regulation of hydrogen peroxide generation in cultured endothelial cells. 154 Mar 80

NADPH-quinone reductase catalyzes the two-electron reduction of quinones such as menadione, and generally is considered to play a protective role against quinone-mediated toxicity. Recent studies have shown that reactive oxygen intermediates may be produced during metabolism of quinones by quinone reductase. Experiments were carried out to evaluate the effect of iron complexes on production of hydroxyl radical (.OH) when menadione was oxidized by a rat liver cytosolic fraction. Menadione-stimulated H2O2 production when added to the cytosol; dicoumarol, a potent inhibitor of quinone reductase, completely blocked this stimulation. Results were identical with either NADH or NADPH as reductant. In the absence of added iron, .OH, assessed as oxidation of chemical scavengers, was not produced. Various ferric chelates, added to the cytosol in the absence of menadione, did not catalyze .OH production. However, .OH was produced in the presence of menadione with all ferric complexes evaluated except for ferric-desferrioxamine. Catalase, competitive scavengers and GSH inhibited .OH production, as did dicoumarol. Superoxide dismutase inhibited with ferric-ATP, ferric-citrate, ferric-histidine or ferric ammonium sulfate as iron catalysts, but had no effect with ferric-EDTA or ferric-diethylenetriamine penta-acetic acid. Reduction of the ferric complexes was increased by menadione. NADH and NADPH were equally effective as cofactor for all these reactions. Metabolism of menadione in the presence of iron complexes caused inactivation of enzymes present in the cytosolic fraction such as glutamine synthetase and lactic dehydrogenase. These results indicate that metabolism of menadione by quinone reductase can lead to the production of .OH in the presence of various ferric catalysts.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Requirement for iron for the production of hydroxyl radicals by rat liver quinone reductase. 769 Apr

Oxygen-derived free radical injury has been associated with several cytopathic conditions. Oxygen radicals produced by chondrocytes is an important mechanism by which chondrocytes induce matrix degradation. In the present study, we extend these observations by studying oxidative processes against osteoblasts. Osteoblasts were mixed in in vitro culture with 200 microM menadione. The cytotoxic effect of menadione-induced oxidative stress was monitored by lucigenin- or luminol-amplified chemiluminescence, tetrazolium assay and immunocytochemical study. Results showed that adding menadione induces an oxidative stress on osteoblasts, via superoxide and hydrogen peroxide production, that can be eradicated by superoxide dismutase (SOD) and catalase in a dose-dependent manner. Catalase and the appropriate concentration of dimethyl sulfoxide have a protective effect on cytotoxicity induced by menadione, whereas SOD does not. Menadione-treated osteoblasts have a strong affinity for annexin V, and the nuclei are strongly stained by TUNEL (TdT-mediated dUTP nick-end labelling). The results suggest that menadione-triggered production of reactive oxygen species leads to apoptosis of osteoblasts.
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PMID:Menadione-induced cytotoxicity to rat osteoblasts. 944 50

To elucidate the significance of oxidative stress in the modulation of endothelial functions, we examined the effects of H(2)O(2) on the expression of two endothelium-derived vasoactive peptides, endothelin (ET) and adrenomedullin (Am), and their interaction. H(2)O(2) dose dependently suppressed ET secretion and ET-1 mRNA expression in bovine carotid endothelial cells (ECs). Menadion sodium bisulfate, a redox cycling drug, also decreased ET secretion in a dose-dependent manner. Catalase, a H(2)O(2) reductase, and dl-alpha-tocopherol (vitamin E) significantly inhibited H(2)O(2)-induced suppression of ET secretion. Downregulation of ET-1 mRNA under oxidative stress was regulated at the transcriptional level. In contrast, H(2)O(2) increased Am secretion (and its mRNA expression) accompanied by the augmentation of cAMP production. Am, as well as 8-bromo-cAMP and forskolin decreased ET secretion in a dose-dependent fashion. Furthermore, an anti-Am monoclonal antibody that we developed abolished H(2)O(2)-induced suppression of ET secretion at 6-24 h after the addition of H(2)O(2). H(2)O(2) increased the intracellular Ca(2+) concentration ([Ca(2+)](i)). Moreover, treatment with ionomycin, a Ca(2+) ionophore, and thapsigargin, an inhibitor of endoplasmic reticulum ATPase, decreased ET secretion dose dependently for 3 h. These results suggest that the production of ET was decreased via activation of the Am-cAMP pathway and by the elevation of [Ca(2+)](i) under oxidative stress. These findings elucidate the coordinate expression of two local vascular hormones, ET and Am, under oxidative stress, which may protect against vascular diseases.
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PMID:Coordinate regulation of endothelin and adrenomedullin secretion by oxidative stress in endothelial cells. 1151 8

Previous studies demonstrated that menadione, a representative quinone compound, reacts nonenzymatically with thiols in plasma, resulting in the generation of reactive oxygen species and potentiation of menadione-induced platelet damage. Because of the reported association of menadione with hemolytic anemia in vivo, investigations were undertaken to identify the free radicals generated from the interaction of menadione with plasma, and to assess the potential role of plasma-generated free-radical species in menadione-dependent erythrocyte toxicity. In rat plasma, menadione increased the rate of oxygen consumption and both luminol- and lucigenin-amplified chemiluminescence in a concentration-dependent manner. Superoxide dismutase (SOD) inhibited lucigenin-amplified chemiluminescence, suggesting formation of superoxide anion. Menadione also induced significant increases in chemiluminescence when erythrocytes were suspended in plasma, but not when cells were suspended in buffer. Consistent with these findings, menadione-dependent hemolysis of erythrocytes occurred only when the cells were suspended in plasma. Various free-radical inhibitors were tested for their ability to inhibit menadione-induced hemolysis. Catalase and mannitol each produced significant inhibition, including an additive effect when both compounds were present, while SOD had no marked effect. In addition, pretreatment with 3-amino-1,2,4-triazole, an intracellular catalase inhibitor, potentiated menadione-induced cytotoxicity in the presence of plasma. These results suggest that both hydrogen peroxide and hydroxyl radicals are involved in menadione-mediated plasma erythrocyte cytotoxicity; however, superoxide anion does not appear to play a direct role.
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PMID:Adverse consequences of erythrocyte exposure to menadione: involvement of reactive oxygen species generation in plasma. 1154 21

Vitamin K3 (VK3) is a well-known anticancer agent, but its mechanism remains elusive. In the present study, VK3 was found to simultaneously induce cell death, reactive oxygen species (ROS) generation, including superoxide anion (O2*-) and hydrogen peroxide (H2O2) generation, and histone hyperacetylation in human leukemia HL-60 cells in a concentration- and time-dependent manner. Catalase (CAT), an antioxidant enzyme that specifically scavenges H2O2, could significantly diminish both histone acetylation increase and cell death caused by VK3, whereas superoxide dismutase (SOD), an enzyme that specifically eliminates O2*-, showed no effect on both of these, leading to the conclusion that H2O2 generation, but not O2*- generation, contributes to VK3-induced histone hyperacetylation and cell death. This conclusion was confirmed by the finding that enhancement of VK3-induced H2O2 generation by vitamin C (VC) could significantly promote both the histone hyperacetylation and cell death. Further studies suggested that histone hyperacetylation played an important role in VK3-induced cell death, since sodium butyrate, a histone deacetylase (HDAC) inhibitor, showed no effect on ROS generation, but obviously potentiated VK3-induced histone hyperacetylation and cell death. Collectively, these results demonstrate a novel mechanism for the anticancer activity of VK3, i.e., VK3 induced tumor cell death through H2O2 generation, which then further induced histone hyperacetylation.
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PMID:Vitamin K3 triggers human leukemia cell death through hydrogen peroxide generation and histone hyperacetylation. 1625 25

The use of frozen semen in the swine industry is limited by problems with viability and fertility compared with liquid semen. Part of the reduction in sperm motility and fertility associated with cryopreservation may be due to oxidative damage from excessive or inappropriate formation of reactive oxygen species (ROS). Chemiluminescence measurements of ROS are not possible in live cells and are problematic because of poor specificity. An alternative approach, flow cytometry, was developed to identify viable boar sperm containing ROS utilizing the dyes hydroethidine and 2', 7'-dichlorodihydrofluorescein diacetate as oxidizable substrates and impermeant DNA dyes to exclude dead sperm. The percentage of sperm with high mitochondrial transmembrane potential was determined by flow cytometry using the mitochondrial probe 5, 5', 6, 6'-tetrachloro-1, 1', 3, 3'-tetraethylbenzimidazolylcarbocyanine iodide with propidium iodide staining to exclude nonviable cells. Sperm were incubated with and without ROS generators and free radical scavengers. Basal ROS formation was low (less than 4%) and did not differ (P = 0.26) between viable fresh and frozen-thawed boar sperm. In addition, fresh and frozen-thawed viable sperm were equally susceptible (P = 0.20) to intracellular formation of ROS produced by xanthine/xanthine oxidase (94.4 and 87.9% of sperm, respectively). Menadione increased (P < 0.05) ROS formation, decreased (P < 0.05) JC-1-aggregate fluorescence intensity, and decreased (P < 0.05) motion variables by 25 to 60%. The mechanism of inhibition of motility by ROS formation may be related to a decrease in mitochondrial charge potential below a critical threshold. Catalase and superoxide dismutase treatment in the presence of xanthine/xanthine oxidase indicated that hydrogen peroxide was the primary intracellular ROS measured. Further, catalase, but not superoxide dismutase, was capable of attenuating ROS-induced inhibition of motility. Whereas basal intracellular hydrogen peroxide formation was low in viable fresh and frozen-thawed boar sperm, both were quite susceptible to external sources of hydrogen peroxide.
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PMID:Determination of intracellular reactive oxygen species and high mitochondrial membrane potential in Percoll-treated viable boar sperm using fluorescence-activated flow cytometry. 1686 69

A strictly anaerobic, mesophilic, sulfate-reducing bacterial strain (MSL86(T)) isolated from an estuarine sediment in the Sea of Japan (around the Japanese islands) was characterized phenotypically and phylogenetically. The cells were found to be Gram-negative, motile, non-spore-forming rods. Catalase was not detected. The optimum NaCl concentration for growth was 1.0 % (w/v) and the optimum temperature was 35 degrees C. Strain MSL86(T) was slightly alkaliphilic, with optimum growth at pH 7.5-7.6. Organic electron donors were incompletely oxidized to (mainly) acetate. Strain MSL86(T) utilized formate, pyruvate, lactate, fumarate, ethanol, propanol, butanol and glycerol as electron donors for sulfate reduction and did not use acetate, propionate, butyrate, succinate, malate, methanol, glycine, alanine, serine, aspartate, glutamate or H(2). Sulfite, thiosulfate and fumarate were used as electron acceptors with lactate as an electron donor. Without electron acceptors, the strain fermented pyruvate and fumarate. The genomic DNA G+C content was 54.4 mol%. Menaquinone MK-8(H(4)) was the major respiratory quinone. The major cellular fatty acids were C(16 : 0), C(16 : 1)omega7, C(16 : 1)omega5 and C(17 : 1)omega6. A phylogenetic analysis based on the 16S rRNA gene sequence placed the strain in the class Deltaproteobacteria. The recognized bacterium most closely related to strain MSL86(T) was [Desulfobacterium] catecholicum DSM 3882(T) (sequence similarity 94.4 %), and the next most closely related recognized species were Desulfotalea psychrophila (94.2 % sequence similarity with the type strain) and Desulfotalea arctica (93.7 %). As the physiological and chemotaxonomic characteristics of MSL86(T) were distinctly different from those of any related species, a novel genus and species Desulfopila aestuarii gen. nov., sp. nov. are proposed to accommodate the strain. The type strain of Desulfopila aestuarii is MSL86(T) (=JCM 14042(T)=DSM 18488(T)).
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PMID:Desulfopila aestuarii gen. nov., sp. nov., a Gram-negative, rod-like, sulfate-reducing bacterium isolated from an estuarine sediment in Japan. 1732 77

A strictly anaerobic, mesophilic, sulfate-reducing bacterial strain, designated MSL71T, was isolated from an estuarine sediment from the Sea of Japan bordering the Japanese islands and was characterized phenotypically and phylogenetically. The cells were found to be Gram-negative, motile, non-spore-forming, slightly curved rods. Catalase and oxidase activities were not detected. The optimum NaCl concentration for growth was 2.0 % (w/v), the optimum temperature was 30 degrees C and the optimum pH was 6.3. Strain MSL71T utilized formate, butyrate, pyruvate, lactate, malate, ethanol, propanol, butanol, glycerol and H2 as electron donors for sulfate reduction. The organic electron donors used were incompletely oxidized, mainly to acetate. The strain did not use acetate, propionate, fumarate, succinate, methanol, glycine, alanine, serine, aspartate or glutamate. Sulfite and thiosulfate were used as electron acceptors with lactate as an electron donor, but fumarate was not utilized. Without electron acceptors, pyruvate and malate, but not lactate or fumarate, were fermented. The genomic DNA G+C content was 62.0 mol%. Menaquinone MK-8(H4) was the major respiratory quinone. The major cellular fatty acids were C14 : 0, C16 : 0, C16 : 1 omega 7, C18 : 1 omega 9, C18 : 1 omega 7 and C14 : 0 3-OH. A phylogenetic analysis based on the 16S rRNA gene sequence placed the strain in the class Deltaproteobacteria. The closest recognized relative of strain MSL71T was Desulfofrigus fragile (93.9 % sequence similarity) and the next closest recognized species was Desulfofrigus oceanense (93.5 %). On the basis of the significant differences in the 16S rRNA gene sequence and phenotypic characteristics between strain MSL71T and each of the related species, a novel genus and species, Desulfoluna butyratoxydans gen. nov., sp. nov., are proposed to accommodate strain MSL71T. The type strain is MSL71T (=JCM 14721T=DSM 19427T).
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PMID:Desulfoluna butyratoxydans gen. nov., sp. nov., a novel Gram-negative, butyrate-oxidizing, sulfate-reducing bacterium isolated from an estuarine sediment in Japan. 1839 77

A strictly anaerobic, mesophilic, sulfate-reducing bacterial strain (MSL79T) isolated from an estuarine sediment in the Sea of Japan of the Japanese islands was characterized phenotypically and phylogenetically. Cells were Gram-negative, motile with a polar flagellum, non-spore-forming, curved rods. Cells had desulfoviridin and c-type cytochrome. Catalase and oxidase activities were not detected. The optimum NaCl concentration for growth was 2.0% (wt/vol). The optimum temperature was 35 degrees C and the optimum pH was 6.5. Strain MSL79T utilized H2, formate, pyruvate, lactate, fumarate, malate, succinate, ethanol, propanol and butanol as electron donors for sulfate reduction. The organic electron donors were incompletely oxidized to mainly acetate. Sulfite and thiosulfate were used as electron acceptors with lactate as an electron donor. Without electron acceptors, pyruvate, fumarate and malate supported the growth. The genomic DNA G+C content was 62.1 mol%. Menaquinone MK-6(H2) was the major respiratory quinone. Major cellular fatty acids were C16:0, iso-C15:0, anteiso-C15:0, iso-C17:0, anteiso-C17:0 and iso-C17:1omega9. Phylogenetic analysis based on the 16S rRNA gene sequence as well as the alpha-subunit of dissimilatory sulfite reductase gene sequence assigned the strain to the family Desulfovibrionaceae within the class Deltaproteobacteria. The closest validly described species based on the 16S rRNA gene sequences were Desulfovibrio aespoeensis (sequence similarity; 95.0%) and Desulfovibrio profundus (94.3%). On the basis of the significant differences in the 16S rRNA gene sequences and the phenotypic characteristics between strain MSL79T and each of the most closely related species, Desulfovibrio portus sp. nov. is proposed. The type strain is MSL79T (=JCM 14722T=DSM 19338T).
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PMID:Desulfovibrio portus sp. nov., a novel sulfate-reducing bacterium in the class Deltaproteobacteria isolated from an estuarine sediment. 1943 29


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