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)

The enzymes involved in antioxidative activity and the cellular content of the antioxidants glutathione and ascorbate in the cyanobacteria Nostoc muscorum 7119 and Synechococcus 6311 have been examined for their roles in hydroperoxide removal. High activities of ascorbate peroxidase and catalase were found in vegetative cells of both species and in the heterocysts of N. muscorum. The affinity of ascorbate peroxidase for H2O2 was 15- to 25-fold higher than that of catalase. Increased activity of ascorbate peroxidase was observed in N. muscorum when H2O2 production was enhanced by photorespiration. Catalase activity was decreased in dilute cultures whereas ascorbate peroxidase activity increased. Ascorbate peroxidase activity also increased when the CO2 concentration was reduced. Ascorbate peroxidase appears to be a key enzyme in a cascade of reactions regenerating antioxidants. Dehydroascorbate reductase was found to regenerate ascorbate, and glutathione reductase recycled glutathione. In vegetative cells glutathione was present in high amounts (2-4 mM) whereas the ascorbate content was almost 100-fold lower (20-100 microM). Glutathione peroxidase was not detected in either cyanobacterium. It is concluded from the high activity of ascorbate peroxidase activity and the levels of antioxidants found that this enzyme can effectively remove low concentrations of peroxides. Catalase may remove H2O2 produced under photooxidative conditions where the peroxide concentration is higher.
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PMID:Hydroperoxide metabolism in cyanobacteria. 308 78

Xanthine (X) and xanthine oxidase (XO) were injected intratracheally (IT) in hamsters at Day 0 (38 mg X, 100 micrograms XO) and Day 5 (38 mg X, 250 micrograms XO). Control hamsters received saline or X (38 mg) plus boiled XO (100, 250 micrograms). Cytoplasmic superoxide dismutase (SOD) activity increased from control of 286 to 337 and 335 units/lung at Days 12 and 19, respectively, but decreased to 228 units/lung at Day 33; mitochondrial SOD activity increased at Day 12 from control of 57 to 71 units/lung and then decreased at Days 26 and 33 to 42 and 33 units/lung, respectively. Glutathione peroxidase (GP) and glutathione reductase (GR) activities rose from their control values of 1161 and 1151 to 1561 and 2287 units/lung at Day 12, respectively; thereafter, GR activity decreased to 512 and 462 units/lung at Days 19 and 26, respectively. Glutathione transferase declined at Day 12 but increased at Day 26 after initial treatment. Glucose-6-phosphate dehydrogenase activity declined from control of 1071 to 693 units/lung at Day 2 and returned to control thereafter. Catalase activity remained unaffected. Hydroxyproline was increased from 903 micrograms/lung in control to 1080, 1301, 1195, and 1148 micrograms/lung at Days 12, 19, 26, and 33, respectively. Malonaldehyde increased from 40 nmole/lung in control to 70 and 113 nmole/lung at Days 12 and 33, respectively. The ratio of right ventricle to left ventricle and septum increased significantly from control of 0.277 to 0.318 at Day 33. Histopathology at Days 2 and 4 revealed peribronchiolar and arteriolar inflammation, and diffuse alveolitis. By Day 12 there were thickened alveolar septa and foci of fibrotic consolidation.
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PMID:Effects of intratracheal administration of xanthine plus xanthine oxidase on lung antioxidant enzymes, lipid peroxidation, and collagen in hamsters. 319 17

There is increasing evidence that islet beta cells may be susceptible to redox insult, and that this susceptibility may contribute to the pathogenesis of experimental models of diabetes mellitus. We investigated the effect of vitamin E deficiency, selenium deficiency, and combined deficiency on islet function and free radical scavenging systems. The tissue levels of glutathione peroxidase, catalase, and immunoreactive superoxide dismutases were measured in four groups of rats (i.e., controls and those with vitamin E, selenium, and combined deficiency). Glucose tolerance tests were performed for each animal before sacrifice. Superoxide dismutase concentrations in liver, heart, and skeletal muscle were within 20% of the control levels in all groups. However, the manganosuperoxide dismutase concentrations in islets were significantly lower than control levels in response to vitamin E, selenium, and combined deficiency. Combined deficiency appeared to have an additive effect. In contrast, cuprozinc superoxide dismutase concentration in islets was higher in the deficient groups than in controls. Insulin secretory reserve was decreased in each of the three deficient groups. This decrease was reflected as glucose intolerance only in the group with combined deficiency. Glutathione peroxidase activity was markedly decreased in selenium-deficient animals in all tissues studied. Catalase activity did not change significantly among groups in any tissue studied. Islets had the lowest glutathione peroxidase and cuprozinc and total superoxide dismutase levels among tissues studied.
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PMID:Effect of vitamin E deficiency and selenium deficiency on insulin secretory reserve and free radical scavenging systems in islets: decrease of islet manganosuperoxide dismutase. 351 3

Current evidence suggests that bleomycin toxicity may be attributable to its DNA degradative activity possibly via generation of free radicals and O2 metabolites as mediators. Since lipopolysaccharide (LPS) has been known to provide protection against O2 toxicity, which is correlated with increased activity of O2 metabolite-detoxifying enzymes, the effect of this agent on bleomycin-induced pulmonary fibrosis was examined. Endotracheal bleomycin administration caused increased lung collagen synthesis. A single intraperitoneal injection of LPS (500 micrograms/kg) at day zero significantly decreased these increases. Total bleomycin-induced lung collagen increase was also significantly reduced. LPS alone had no significant effect on total lung catalase activity. Glutathiione peroxidase activity, however, was significantly decreased by 15.8% compared to untreated animals at 2 days after LPS treatment and remained unchanged at other time points. In addition, superoxide dismutase activity was significantly elevated by 30% above untreated animals only at 14 days after LPS administration and remained unchanged at other time points. Endotracheal bleomycin administration alone caused significant reductions in catalase activity at 2 days and 2 weeks after treatment, whereas glutathione peroxidase activity increased above control untreated animals at 2 and 4 weeks, respectively. Superoxide dismutase activity was unaffected by bleomycin treatment. Pretreatment with LPS before bleomycin prevented these reductions or caused increases in the activities of these enzymes at 2 days. Glutathione peroxidase was increased and was significantly greater than those animals treated with bleomycin alone. Catalase also was higher in the LPS plus bleomycin group (by 22.2%, p less than 0.05) than the bleomycin group alone. Compared to the effects on lung collagen synthesis and content, LPS treatment resulted in much less dramatic changes in total lung antioxidant enzyme activities. This discrepancy between the intensity of LPS effects on lung O2 metabolite-detoxifying enzymes and that on pulmonary fibrosis implies that the LPS-ameliorating effect on pulmonary fibrosis could not be totally explained by increased ability to detoxify O2 metabolites. Rather, the data would favor the possibility that LPS inhibits bleomycin-induced pulmonary fibrosis either by its known immunosuppressive effects or some other unknown mechanism. The former would be in agreement with previous data which suggest that an intact immune response is necessary for complete expression of the fibrogenic response to bleomycin.
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PMID:Inhibition of bleomycin-induced pulmonary fibrosis by lipopolysaccharide. 620 76

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

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

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

Several lines of evidence support the hypothesis that oxygen free radicals are involved in the destruction of neurons in various degenerative disorders of the central nervous system. The activities of superoxide dismutase, catalase and glutathione peroxidase, three enzymes that contribute to the cellular defenses against free radical damage, were measured in different areas of autopsy brains from patients with Alzheimer's disease and from age matched controls. All brains were removed within 24 hours of the time of death and were cut in half sagitally. One half was stored frozen at -86 degrees C and the other half was examined histologically to confirm the presence or absence of Alzheimer's disease. Samples were taken from the frozen half for the enzyme assays. In control brains, the activity of superoxide dismutase is significantly higher in the cerebellum, frontal cortex and hippocampus than it is in the temporal cortex, parietal cortex and entorhinal cortex. The activity of catalase is significantly higher in cerebellum and frontal cortex than in hippocampus, parietal cortex and entorhinal cortex. Glutathione peroxidase activity is uniform across all brain areas studied. In Alzheimer's brains, superoxide dismutase activity is not statistically different among the various brain regions studied, but it is significantly lower than control in the cerebellum (-27%), frontal cortex (-27%) and hippocampus (-35%). Catalase is significantly higher in Alzheimer's cerebellum, frontal cortex and temporal cortex than in Alzheimer's hippocampus, parietal cortex and entorhinal cortex. However, there are no significant differences in catalase activity between Alzheimer's and control samples.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Regional brain activity of free radical defense enzymes in autopsy samples from patients with Alzheimer's disease and from nondemented controls. 805 Aug 54

The effects of aging on the activities of drug-metabolizing enzymes and antioxidant enzymes were studied in male and female White-Footed mice (Peromyscus leucopus) at ages of 6, 8, 12, 18, 24, 30, 36, and 48 months. Male mice had significantly higher liver microsomal cytochrome P450 (P450) content and NADPH:cytochrome P450 oxidoreductase (P450 reductase) activities than females at all age groups. Many of the P450-dependent enzyme activities were also generally higher in males. Female mice showed age-dependent decreases in P450 content and the activities of P450 reductase, pentoxyresorufin O-dealkylase (PROD) and N-nitrosodimethylamine demethylase (NDMAd) in the liver from 6 to 24 months; while, the males showed an age-dependent decrease only for the liver PROD activity from 6 to 24 months. The old males (30-month old) appeared to have significantly higher activities for 6 beta-, 2 beta-, 16 alpha- and 16 beta-testosterone and androstenedione formation than the middle-aged (6- to 18-month old) and very old (48-month old) males. Females showed age-dependent decreases for the formation of 6 beta-, 2 beta-, 16 alpha- and 16 beta-testosterone in liver microsomes from 6 to 24 months. Lung microsomes from 6- and 8-month old males had much higher activities of ethoxyresorufin O-deethylase (EROD) and PROD than older males. The total NNK alpha-hydroxylation activities changed in the same pattern as lung microsomal EROD and PROD activities in both male and female mice. The activities of several phase II drug-metabolizing enzymes: glutathione S-transferase (GST), DT-diaphorase, sulfotransferase and UDP-glucuronosyl-transferase (UDPGT) did not show any significant age-dependent changes, with the possible exception that the GST activity in males decreased from 18 to 36 months. Males had about 3-fold higher UDPGT activities than females among all age groups. Glutathione peroxidase activities were drastically lower in old and very old males, and 6 to 24 months old males had significantly higher activities than the corresponding females. In females, superoxide dismutase activities decreased linearly to extremely low levels as mice aged. Catalase activities showed a tendency for increase with age in males. In conclusion, some P450-dependent activities and antioxidant enzymes, but not phase II drug-metabolizing enzymes, showed age-dependent changes; and most of these changes occur from 6 to 24 months. The demographic attributes of the White-Footed mouse are well-suited for physiological and biochemical studies of aging and can complement the more standard laboratory mouse model with its typical two year life span.
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PMID:Age- and gender-related variations in the activities of drug-metabolizing and antioxidant enzymes in the white-footed mouse (Peromyscus leucopus). 849 97


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