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)

Methanol and ethanol were rapidly metabolized to formaldehyde and acetaldehyde in the presence of ascorbate, 1,10-phenanthroline and either guinea pig hepatic 100,000 g supernatant or 12,000 g pellet fractions. The specific activity of methanol oxidation was 1720 nmoles formaldehyde formed/min/mg protein in the 100,000 g fraction and 790 in the 12,000 g pellet fraction. The specific activity of ethanol oxidation was 1590 nmoles acetaldehyde formed/min/mg protein in the 100,000 g fraction and 820 in the 12,000 g pellet fraction. The activity was enzymatic in that it was linear with time, proportional to protein concentration, and sensitive to temperature. Catalase appeared to be the enzymatic component responsible for the oxidation. In this ascorbate-dependent alcohol oxidation system, oxygen was consumed and H2O2 was formed. When purified catalase and ascorbate were used, complex I was detected and methanol was oxidized.
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PMID:Ascorbic acid and alcohol oxidation. 650 46

As natural killer (NK) cell activity is an essential constituent of host defence systems and reactive oxygen intermediates participate in such defence, the effect of scavengers of oxygen radicals on NK cell activity was investigated. Hydroxyl radical (OH) scavengers (dimethyl sulphoxide (DMSO), thiourea, dimethylurea, tetramethylurea, benzoic acid, ethanol, methanol and ethylene glycol) inhibited NK cell activity. Catalase, a scavenger of H2O2, and superoxide dismutase (SOD), a scavenger of O-2, either alone or in combination, did not inhibit NK cell activity. Inhibition of the lipoxygenase pathway of arachidonic acid metabolism, a potential source of cellular OH, with nordihydroguaiaretic acid and 5,8,11,14-eicosatetraynoic acid (ETYA) resulted in marked inhibition of NK cell activity. Inhibition of the cyclooxygenase pathway with acetylsalicylic acid or indomethacin had minimal effects on NK cell activity. Taken together, these findings suggest that OH, possibly generated via the lipoxygenase pathway of arachidonic acid metabolism, is critical for NK cell cytotoxicity.
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PMID:Hydroxyl radical scavengers inhibit human natural killer cell activity. 669 28

Catalase promotes the H2O2-dependent oxidation of phenylhydrazine to benzene but simultaneously is subject to a pseudo-first order inactivation process. Each inactivation event is subtended by catalytic turnover of three molecules of phenylhydrazine and 52 molecules of H2O2. The dimethyl ester of N-phenylprotoporphyrin IX is extracted with acidic methanol from the inactivated enzyme, but the prosthetic heme with a phenyl sigma-bonded to the iron atom is obtained by gentle extraction with 2-butanone. The absolute chirality of N-ethylprotoporphyrin IX isolated from catalase inactivated with ethylhydrazine confirms that the prosthetic heme has the same chiral orientation in the active site as it does in hemoglobin. The known inactivation of methemoglobin by phenylhydrazine is shown to depend on H2O2 but not oxygen. The results demonstrate that the H2O2-dependent oxidation of phenylhydrazine by catalase and other hemoproteins results in sigma-coordination of a phenyl residue to the prosthetic heme iron. This process may play a role not only in phenylhydrazine-mediated erythrocyte lysis but also in the activation of guanylate cyclase.
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PMID:Inactivation of catalase by phenylhydrazine. Formation of a stable aryl-iron heme complex. 688 92

The substructural organization of completely crystalline peroxisomes present in Hansenula polymorpha cells grown under methanol limitation in a chemostat was investigated by different cytochemical and ultrastructural techniques. Time-dependent cytochemical staining experiments indicated that activities of the two main constituents of these organelles, namely, alcohol oxidase and catalase, were present throughout the crystalline matrix. Catalase was completely removed from isolated peroxisomes by osmotic shock treatment. After such treatment, the ultrastructure of the crystalline matrix of the organelles remained virtually intact. Because alcohol oxidase activity was still present in this matrix, it was concluded that alcohol oxidase protein is the only structural element of the peroxisomal crystalloids. The molecular architecture of the crystalloids was investigated in ultrathin cryosections which permitted recognition of individual molecules in the crystalline matrix. Depending on the plane of sectioning, different crystalline patterns were observed. Tilting experiments indicated that these images were caused by superposition of octameric alcohol oxidase molecules arranged in a tetragonal lattice. A three-dimensional model of the crystalloid is presented. The repeating unit of this structure is composed of four alcohol oxidase molecules. The crystalloid represents an open structure, which may explain the observed free mobility of catalase molecules.
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PMID:Substructure of crystalline peroxisomes in methanol-grown Hansenula polymorpha: evidence for an in vivo crystal of alcohol oxidase. 705 Jun 59

Catalase, the classical peroxisomal marker enzyme, decomposes hydrogen peroxide and is involved in the antioxidant defense mechanisms of mammalian cells. In addition, catalase can oxidize, by means of its peroxidatic activity, a variety of substrates such as methanol and ethanol, producing the corresponding aldehydes. The involvement of brain catalase in the oxidation of ethanol is well established, and severe afflictions of the CNS in hereditary peroxisomal diseases (e.g., Zellweger syndrome) are well known. Whereas the distribution of catalase in the CNS has been investigated by enzyme histochemistry and immunohistochemistry (IHC), very little is known about the exact localization of catalase mRNA in brain. Here we report the application of a tyramine/CARD (catalyzed reporter deposition)-enhanced nonradioactive in situ hybridization (ISH) protocol for detection of catalase mRNA in sections of perfusion-fixed, paraffin-embedded rat brain. Catalase mRNA could be demonstrated in a large number of neurons throughout the rat brain as a distinct cytoplasmic staining signal with excellent morphological resolution. Compared to our standard ISH protocol, the CARD-enhanced protocol for catalase mRNA detection in rat brain showed higher sensitivity and significantly better signal-to-noise ratio. In parallel IHC experiments, using an antigen retrieval method consisting of combined trypsin digestion and microwave treatment of paraffin sections, the catalase antigen was found as distinct cytoplasmic granules in most catalase mRNA-positive neurons. In addition, catalase-positive granules, presumably peroxisomes, were found by confocal laser scanning microscopy in glial cells, which were identified by double labeling immunofluorescence for GFAP and CNPase for astroglial cells and oligodentrocytes, respectively. The excellent preservation of morphology and sensitive detection of both mRNA and protein in our preparations warrant the application of the protocols described here for systematic studies of catalase and other peroxisomal proteins in diverse pathological conditions such as Alzheimer's disease and aging.
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PMID:Expression of catalase mRNA and protein in adult rat brain: detection by nonradioactive in situ hybridization with signal amplification by catalyzed reporter deposition (ISH-CARD) and immunohistochemistry (IHC)/immunofluorescence (IF). 1275 86

Mouse embryos are more sensitive than rat embryos in response to methanol (CH(3)OH) and its ability to elicit developmental abnormalities. Intrinsic differences in the metabolism of CH(3)OH to formaldehyde (HCHO) and formic acid (HCOOH) by the enzymes alcohol dehydrogenase (ADH1), formaldehyde dehydrogenase (ADH3), and catalase may contribute to the observed species sensitivity. Specific activities for enzymes involved in CH(3)OH metabolism were determined in rat and mouse conceptuses during the organogenesis period of 8-25 somites. Spatial activity relationships were also compared separately in heads, hearts, trunks, and the visceral yolk sac (VYS) from early (7-12 somites) and late (20-22 somites) organogenesis-stage rat and mouse embryos. Catalase activities were similar between rat and mouse conceptuses. In the mouse heart, catalase activities were consistently lower when compared to other tissues. Specific activities for catalase were consistently highest in the VYS of both species when compared to other tissues of the embryo. These activities were highly significant in the 6-12 somite VYS. ADH1 activities were significantly higher in embryos when compared to VYS in both species, except for a 27% lower activity in the early 8-10 somite mouse embryo. Mouse ADH1 activities in the VYS were significantly lower throughout the organogenesis period when compared to the rat VYS or embryos of either species. Mouse activities were lower overall in specific tissues of the embryo but maintained the same relative proportions as in the rat. ADH3 activities in the rat VYS were significantly higher by 20% than those in the mouse. Mouse embryo ADH3 activities were slow to mature, starting at a level 42% below rat, and failed to reach optimal levels until the 14-16-somite stage. Heart ADH3 activities were also significantly lower in the mouse embryo at the 7-12-somite stage. Both species have lower ADH3 activities in the early heart, relative to other embryonic tissues. These results show a more slowly maturing capacity of the mouse embryo to remove HCHO, which provides a rationale for increased sensitivity of this species to CH(3)OH-induced embryotoxicity and teratogenicity.
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PMID:Methanol metabolism and embryotoxicity in rat and mouse conceptuses: comparisons of alcohol dehydrogenase (ADH1), formaldehyde dehydrogenase (ADH3), and catalase. 1275 5

Methanol is primarily metabolized by oxidation to formaldehyde and then to formic acid. These processes are accompanied by formation of superoxide anion and hydrogen peroxide. This paper reports the in vitro antioxidant effect of vitamin E on isolated hepatocytes of folic acid deficient rats rendered so as to emulate a human hepatocyte model. These hepatocytes were treated with 320 microM of methanol per million cells and incubated for 30 min. The microsomal fraction of these hepatocytes showed a decreased level of superoxide dismutase (SOD), with increase in lipid peroxidation (LPO) shown by increase in recorded levels of malondialdehyde (MDA). Catalase activity was shown to be increased. Levels of reduced glutathione (GSH) were decreased and the activity of glutathione peroxidase (GSH-Px) and of glutathione reductase (GSSG-R) were not altered. The hepatocytes of folate deficient rats pretreated with vitamin E, when subjected to methanol treatment, showed no significant change in SOD levels and a significant decrease in MDA levels. The catalase activity in this group of animals showed a highly significant decrease. These animals had normal levels of GSH, while a significant fall in GSH-Px and GSSG-R levels were observed. These results suggest that Vitamin E exerts a protective effect on hepatocytes by acting as a free radical scavenger, proving its usefulness in treating methanol toxicity.
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PMID:In vitro effect of methanol on folate-deficient rat hepatocytes. 1282 Dec 9

In the first pass methanol biotransformation three enzymatic systems: alcohol dehydrogenase (ADH), microsomal alcohol oxidising system (MEOS) linked with cytochrome P-450 and catalase are involved. Because of the toxicity of methanol, which is directly caused by its toxic metabolites, the major task in clinical toxicology is to inhibit each of these enzymes to protect human life. The aim of this investigation was to check the influence of some effective inhibitors of ADH and MEOS: 4-methylpyrazole, cimetidine, EDTA and 1,10-phenantroline on the activity of catalase with methanol as a substrate and the comparison with 3-amino-1,2,4-triasole. Catalase activity in rat hepatic homogenates was measured spectrophotometrically in vitro at physiological pH 7.4 and temp. 37 degrees C, assaying the degree of methanol oxidation according to Handler and Thurman. The quantity of arising formaldehyde was measured according with the method of Nash. Our results have shown that catalase activity was inhibited to different extents by all investigated compounds at concentrations of 10(-3) mol/l, 2 x 10(-4) mol/l, 10(-4) mol/l, 2 x 10(-5) mol/l, 10(-5) mol/l. 1,10-Phenantroline was found to be a highly effective inhibitor in comparison with aminotriasole. 4-Methylpyrazole, EDTA, 1,10-phenantroline and aminotriasole are catalase competitive inhibitors and cimetidine is non-competitive inhibitor. 4-Methylpyrazole has shown higher affinity to the enzyme than aminotriasole.
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PMID:[Activity of catalase after administration of some ADH and MEOS inhibitors: in vitro investigation in rat liver homogenates]. 1505 35

Retinal photoreceptors and retinal pigment epithelial (RPE) cells are among the cell types that are sensitive to poisoning with methanol and its toxic metabolite formic acid. When exposed to formic acid in vitro, cultured cell lines from photoreceptors (661W) and the RPE (ARPE-19) were previously shown to accumulate similar levels of formate, but cytotoxic effects are greater in 661W cells. Here catalase and glutathione were analyzed in the two retinal cell lines to determine whether differences in these antioxidant systems contributed to cell-type-specific differences in cytotoxicity. Cells were exposed to formic acid (pH 6.8) in the culture medium in the presence or absence of a catalase activity inhibitor, 3-amino-1,2,4-triazole (AT), or a glutathione synthesis inhibitor, buthionine L-sulfoximine (BSO). Catalase protein, catalase enzyme activity, glutathione, glutathione peroxidase activity, cellular ATP, and cytotoxicity were analyzed. Compared to ARPE-19, 661W cells show lower antioxidant levels: 50% less glutathione, glutathione peroxidase and catalase protein, and 90% less catalase enzyme activity. In both cell types, formic acid treatment produced decreases in glutathione and glutathione peroxidase, and glutathione synthesis inhibition with BSO produced greater ATP depletion and cytotoxicity than formic acid treatment alone. In contrast, formate exposure produced decreases in catalase protein and activity in 661W cells, but increases in activity in ARPE-19. Treatment with the catalase inhibitor AT increased the formate sensitivity only of the ARPE-19 cells. ARPE-19 cells, therefore, may be less susceptible to formate toxicity due to higher levels of antioxidants, especially catalase, which increases on formate treatment and which has a significant cytoprotective effect for the RPE cell line.
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PMID:Antioxidants and ocular cell type differences in cytoprotection from formic acid toxicity in vitro. 1531 87

In forensic medicine practice poisonings are rather frequent, and among them, those caused by fatal "substitution" of ethyl alcohol. One of the most frequently encountered "substitutes" for ethyl alcohol is methanol. The purpose of our research was to determine the concentration of malonic dialdehyde as the expression of lipid peroxidation and antioxidant enzyme activity after dosed chronic ethyl and methyl alcohol intoxication. The experiment was conducted on approx. 6 month-old male inbred Lewis rats each weighing approx. 250 g. Ethanol and methanol solution was given in the concentration 1.0 M. The control group of rats received water. Each experimental group numbered 30 rats, this number was divided into three sub-groups, which were put-down at 4, 8 and 12 weeks. The activity of superoxide dismutase (CuZu-SOD) was determined by the Misra-Fridovich method, catalase (CAT) by the Beers-Sizer method. The concentration of malonic dialdehyde (MDA) was determined using the method of Placer et al. by assessing the concentration of TBARS compounds. Results are expressed as a mean +/- SD. The paired Student's test for small groups were used. Superoxide dismutase SOD1 activity decreased compared with the control group throughout the duration of the experiment from 2212 U/gHb to 1676 U/gHb for ethanol and from 2212 U/gHb to 945 U/gHb for methanol. Catalase activity for methanol decreased from 9.1 U/gHb to 5.1 U/gHb, for ethanol to 7.4 U/gHb. In the 4th week of the experiment increase of malonyl dialdehyde concentration for methanol group was observed--from 0.14 umol/gHb to 0.34 umol/Hb; after 8th weeks it decreased to 0.2 umol/gHb and in the 12th week increased to 0.23 umol/gHb. For ethanol these changes was less visible and reached the level of 0.24 umol/l. The statistical processing of the results was performed on the basis of parametric tests (the t-Student test for small experiments) and computer software Statistica. The statistical significance was set for p<0.05.
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PMID:[Selected alcohols on the pro- and anti-oxidative processes in rat erythrocytes]. 1549 56


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