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)

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

The permeability of the alveolar-capillary membrane of newborn and adult mice to horseradish peroxidase (HRP) and catalase was studied by means of ultrastructural cytochemistry, and the permeability to ferritin was studied by electron microscopy. The influence of varying volumes of intravenously injected fluid on the rate of leakage of the tracers from pulmonary capillaries was examined. The tracers were injected intravenously and the mice were sacrificed at timed intervals. Experiments on newborn mice with intranasally instilled HRP were also done. The tissues were fixed in formaldehyde-glutaraldehyde fixative. Chopped sections were incubated in Graham and Karnovsky's medium for peroxidase and in a modification of this medium for catalase. Tissues were postfixed in OsO(4) and processed for electron microscopy. In both newborn and adult mice, the ready passage of peroxidase through endothelial clefts was dependent on the injection of the tracer in large volumes of saline. When the tracer was injected in small volumes of saline, its passage through endothelial clefts was greatly reduced. Endothelial junctions of newborn mice were somewhat more permeable to HRP than those of adult mice. In all animals, alveolar epithelial junctions were impermeable to HRP. Catalase and ferritin did not pass through endothelial junctions. Intranasally instilled HRP in newborn mice was taken up by pinocytotic vesicles and tubules of flat alveolar cells.
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PMID:The influence of intravascular fluid volume on the permeability of newborn and adult mouse lungs to ultrastructural protein tracers. 1986 61


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