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)

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

Effects of hypoxia-reoxygenation (H-R) on myocytes isolated from 10 week hypertrophied and sham control rat hearts were studied. Myocyte hypertrophy was indicated by an increase in cell size. Superoxide dismutase (SOD) and glutathione peroxidase (GSHPx) enzyme activities were significantly higher and lipid peroxidation (TBARS) was lower in hypertrophied myocytes prior to any H-R. Hypertrophied myocyte population showed significantly less damage to cell morphology due to H-R. In sham as well as hypertrophied myocytes, Na+ and Ca2+ contents were increased by H-R, but Ca2+ accumulation was significantly less in the hypertrophied myocytes. Both SOD and GSHPx activities were depressed by the oxidative stress in the sham myocytes whereas these activities were not significantly changed in the hypertrophied myocytes. Catalase activity in the prehypoxic sham and hypertrophied myocytes was comparable and this activity did not change during H-R. There was a significant increase in lipid peroxidation due to H-R but this change was less in hypertrophied myocytes. This study shows less vulnerability of hypertrophied myocytes to oxidative stress and an increase in endogenous antioxidant reserve may have an important role in mediating this protection.
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PMID:Endogenous antioxidants in isolated hypertrophied cardiac myocytes and hypoxia-reoxygenation injury. 776 Mar 50

The protein-bound polysaccharide of Coriolus versicolor QUEL (PS-K) expresses the mimicking activity of superoxide dismutase (SOD). Examination was made of the suppressive effects of PS-K on cancer cell lines cultured in vitro. The SOD activity of LLC-WRC-256 (Walker 256 fibrosarcoma) cell lines was less than that of NRK-49F (rat normal kidney fibroblast), H4-II-E (rat hepatoma) and H4-II-E-C3 (rat hepatoma) cell lines. This activity in Walker 256 fibrosarcoma cells increased by 3.6 times and H2O2 concentration, by 2.56 times by PS-K 500 micrograms/ml. Cell proliferation was consequently suppressed and living cells decreased to less than 50% of the cells cultured without PS-K. Catalase and glutathione peroxidase activity changed little by PS-K. The sensitivity of cancer cells to PS-K can be predetermined based on SOD activity in tumor tissue.
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PMID:Suppression of cancer cell growth in vitro by the protein-bound polysaccharide of Coriolus versicolor QUEL (PS-K) with SOD mimicking activity. 781 58

The significance of manganese superoxide dismutase (MnSOD) induction in cells and tissues during oxidant stress is still poorly understood. In this study, transformed human bronchial epithelial cells (BEAS 2B) were treated with interferon-gamma (IFN-gamma), tumor necrosis factor-alpha (TNF-alpha), or with combination of these cytokines (10 ng/ml concentrations) for 48 or 72 h and exposed to selected oxidants. TNF-alpha and IFN-gamma + TNF-alpha combination resulted in a marked increase of MnSOD protein and MnSOD activity. When cells pretreated with the cytokines were exposed to hyperoxia (95% O2, 72 h), menadione (5-50 microM, 4 h), or H2O2 (0.5 and 5 mM, 4 h), in all cases IFN-gamma and TNF-alpha enhanced oxidant-related cell injury. The effect was most significant with cells pretreated with a combination of IFN-gamma and TNF-alpha. Antioxidant enzymes such as total SOD, glutathione peroxidase, glutathione reductase, and glucose-6-phosphate dehydrogenase did not change significantly during the cytokine treatment. Catalase activity was not changed by IFN-gamma or TNF-alpha but it decreased significantly (34%) in IFN-gamma + TNF-alpha-treated cells. Free radical generation was not changed by these cytokines in acute (30 min) experimental conditions or after 48-h treatment. These results suggest that cytokine-induced MnSOD does not protect bronchial epithelial cells against endogenously or exogenously generated oxidants in vitro. In fact, cells that contained the highest MnSOD activity were the most sensitive to subsequent oxidant damage.
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PMID:Mitochondrial superoxide dismutase induction does not protect epithelial cells during oxidant exposure in vitro. 784 Feb 31

In previous studies we have found that a single acute dose of ultraviolet radiation to murine skin causes a large degree of destruction of enzymic and non-enzymic antioxidants immediately after irradiation. In the present study, we wished to elucidate the recovery of antioxidants after a single dose of ultraviolet (UV) radiation. We measured antioxidants and lipid hydroperoxides (as a marker of membrane damage) in murine epidermis and the dermis at 0, 3, 12, 24, 72 and 120 h after exposure to UV radiation (25 J/cm2, UVA+UVB). Lipid hydroperoxides showed the highest values immediately after UV exposure and returned to control values within 24 h in both epidermis and dermis. The activities of catalase, glutathione peroxidase and glutathione reductase showed the lowest activities immediately after UV exposure; superoxide dismutase activities reached a minimum at 3 h postexposure. The pattern of recovery was different for each enzyme and for epidermis and dermis. The activities of superoxide dismutase and catalase decreased remarkably and recovered slowly. Superoxide dismutase in the dermis recovered full activity by 120 h and in the epidermis by 12 h. Catalase activity in both epidermis and dermis had returned to only 50% of control activity at 120 h, although the epidermis showed a temporary increase (to 93%) at 24 h. Glutathione peroxidase and glutathione reductase were slightly decreased immediately after irradiation, recovered to 100% at 3 h and then increased to 200-250% in both the epidermis and the dermis at various times; values had returned to 100% in epidermis by 120 h but remained elevated in dermis.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Recovery of antioxidants and reduction in lipid hydroperoxides in murine epidermis and dermis after acute ultraviolet radiation exposure. 788 Jul 56

We have characterized the effect of angiotensin converting enzyme (ACE) inhibitors on the activity of CuZn-superoxide dismutase (CuZn-SOD), Mn-superoxide dismutase (Mn-SOD), catalase, and selenium-dependent glutathione peroxidase (Se-GPx). CF1 mice (4-month-old females) were administered water containing enalapril (20 mg/l) or captopril (50 mg/l), during 4 to 11 weeks. After 11 weeks, enalapril treatment caused an increase in the activity of CuZn-SOD, Mn-SOD and Se-GPx, from 19 +/- 4 to 46 +/- 7, 2.1 +/- 0.2 to 3.8 +/- 0.2 units/mg protein and 27 +/- 3 to 54 +/- 3 milliunits/mg protein, respectively. After 11 weeks, captopril treatment increased the activities (P < 0.05) of CuZn-SOD, MnSOD and Se-GPx to 35 +/- 4, 2.9 +/- 0.2 units/mg protein, and 38 +/- 2 milliunits/mg protein, respectively. Catalase activity was not affected by the treatments. These results suggest that ACE inhibitors may protect cell components from oxidative damage by increasing the enzymatic antioxidant defenses.
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PMID:Superoxide dismutase and glutathione peroxidase activities are increased by enalapril and captopril in mouse liver. 789 34

Guinea pigs were fed for five weeks with two diets with different levels of vitamin C, low (33 mg of Vit C/Kg diet) and high (13,200 mg of Vit C/Kg of diet). Catalase was inhibited with 3-amino-1,2,4-triazole (AT) in half of the animals from each dietary group. AT caused an almost complete depletion of liver catalase activity (90%) in both dietary groups. Vitamin C supplementation increased total glutathione peroxidase activity and tissue vitamin C level and decreased levels of protein carbonyls and malondialdehyde (MDA) in both treated and non-treated animals. This vitamin C supplementation did not change any of the other antioxidant defences studied. Our results show that dietary vitamin C supplementation increases global antioxidant capacity and decreases endogenous oxidative damage in the guinea pig liver under normal non-stressful conditions. This supports the protective value of dietary antioxidant supplementation.
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PMID:Effect of dietary vitamin C and catalase inhibition of antioxidants and molecular markers of oxidative damage in guinea pigs. 792 Nov 63

The characteristics of the hepatocarcinogenesis induced by dehydroepiandrosterone (DHEA) were compared with that induced by other peroxisome proliferators such as [4-chloro-6-(2,3-xylidino)-2-pyrimidinylthio]acetic acid (Wy-14,643) and di(2-ethylhexyl)phthalate (DEHP). Male F-344 rats were given a diet containing DHEA at 0.5 or 1%, Wy-14,643 at 0.1% and DEHP at 2% for up to 78 weeks. In rats fed 0.5 or 1% DHEA the incidence of neoplasias was 20% after 52 weeks. At 78 weeks all rats treated with 1% DHEA had numerous grossly visible nodules and the incidence of hepatic neoplasia was dose-dependent. The magnitude of hepatocellular tumorigenicity after DHEA treatment was less potent than that after Wy-14,643, but more than that after DEHP treatment. Peroxisomal beta-oxidation activity increased three- or six-fold after a 10 week course of 0.5 or 1% DHEA respectively and this was significantly lower than that induced in Wy-14,643- or DEHP-fed rats. From 52 to 78 weeks these activities increased 3-9 times over that in controls. In both the group of rats treated with Wy-14,643 and those treated with DEHP, peroxisomal beta-oxidation constantly increased 11- to 15-fold during the experiment. Catalase activity increased 1.3- to 1.5-fold for the first 10 weeks of DHEA treatment and then recovered to the control level. The activities of glutathione peroxidase and glutathione S-transferase decreased markedly after 30 weeks in DHEA-treated rats and the decreases were sustained for up to 78 weeks. The profile of changes in enzyme activities in the rats fed DHEA was not significantly different from that of those fed Wy-14,643 or DEHP. There were no increases in 8-hydroxydeoxyguanosine, oxidative DNA damage or lipid peroxide level in the liver in any of the treated rats at 10 or 30 weeks. Since these results showed that the characteristics of hepatocarcinogenesis caused by DHEA were basically similar to those caused by Wy-14,643 and DEHP, typical peroxisome proliferators, hepatocarcinogenesis induced by DHEA is probably due to the same mechanisms as that induced by general peroxisome proliferators.
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PMID:Characteristics of the hepatocarcinogenesis caused by dehydroepiandrosterone, a peroxisome proliferator, in male F-344 rats. 795 56

Human 5-lipoxygenase (5LO) becomes very unstable after purification. Commonly used methods for protein stabilization could not prevent this inactivation. However, addition of small amounts of glutathione peroxidase (0.15 micrograms/ml) and superoxide dismutase (1 microgram/ml) to the solution of purified 5LO (300-500 micrograms/ml) stabilized the enzyme during storage. The protected 5LO maintained full activity for at least 12 days at 25 degrees C, while 50% of the activity was lost within 10 h without protection. Glutathione peroxidase alone also preserved the activity of 5-lipoxygenase; however, the effect declined rapidly in the absence of superoxide dismutase. 2-Mercaptoethanol was the most efficient hydrogen donor substrate for glutathione peroxidase in the protection of 5LO. Catalase was less effective as a stabilizing agent, and ebselen, a synthetic glutathione peroxidase-mimicking compound, did not protect 5LO. Since many metal ion binding proteins are susceptible to H2O2 inactivation, this method could be useful also for the stabilization of other proteins.
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PMID:Stabilization of purified human 5-lipoxygenase with glutathione peroxidase and superoxide dismutase. 797 52


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