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)

Recent studies have implicated free radicals in the pathogenesis of amyotrophic lateral sclerosis (ALS), a fatal, paralytic disorder of motor neurons. Herein we report on measurements of erythrocyte activity of the three main free radical scavenging enzymes: copper/zinc superoxide dismutase (Cu/Zn-SOD), catalase, and glutathione peroxidase. We studied 31 patients with sporadic ALS, 18 with familial ALS, and 24 controls, Mean Cu/Zn-SOD activity was reduced in eight familial ALS patients with mutations of Cu/Zn-SOD but was normal in patients with both familial ALS without identified Cu/Zn-SOD mutations and sporadic ALS. Glutathione peroxidase activity was significantly reduced only in sporadic ALS patients treated with insulin-like growth factor I (100 micrograms/kg). Catalase activity was normal in sporadic and familial ALS. Neither glutathione peroxidase nor catalase activities correlated significantly with duration of symptoms or age at onset. Vitamin E, vitamin C, and beta-carotene did not affect any of the three enzyme activities. These observations indicate that disturbances of catalase and glutathione peroxidase function are not likely to be central factors in the pathogenesis of ALS.
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PMID:Blood superoxide dismutase, catalase and glutathione peroxidase activities in familial and sporadic amyotrophic lateral sclerosis. 873 83

1. The present study was undertaken to investigate the effects of hypobaric hypoxia, equivalent to an altitude of 5500 m, on antioxidant enzymes in rats. 2. Malondialdehyde levels in serum, heart, lung, liver and kidney of hypobaric-hypoxic rats were all significantly higher than in control rats by day 21 of exposure (P < 0.05), indicating increased oxidative stress. 3. Superoxide dismutase (SOD) catalyses the conversion of the superoxide anion to H2O2 and O2. The concentration of immunoreactive Mn-SOD in the serum of hypobaric-hypoxic rats was raised significantly from day 5 onwards, whereas in liver and lung, it had decreased significantly by day 21 (P < 0.05). 4. Glutathione peroxidase (GSH-Px) catalyses H2O2 and certain lipid peroxides. By day 21, GSH-Px activity had increased significantly in the heart and lungs, but decreased significantly in the liver (P < 0.05). 5. Catalase catalyses H2O2. Catalase activity in the liver and kidney of hypobaric-hypoxic rats was significantly decreased on day 1 (P < 0.05) though levels then recovered. 6. Mn-SOD mRNA in the liver of hypobaric-hypoxic rats was induced during the experiment, the effect being exceptionally marked, especially during the first 3 days of exposure to hypobaric hypoxia. 7. These results suggest that the liver may be more vulnerable than the other organs tested to oxidative stress under hypobaric hypoxia.
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PMID:Effects of hypobaric hypoxia on antioxidant enzymes in rats. 878 50

The role of free radicals in p-aminophenol (PAP)-induced nephrotoxicity and effects of reduced glutathione (GSH) were investigated. We injected PAP in one group of rats and PAP plus GSH in a second group. All parameters were measured in the renal tissue. Superoxide dismutase (SOD) activity in the PAP + GSH group (7.1 +/- 0.36 U/mg protein) was found to be significantly higher than in the control group (4.9 +/- 0.13) (P < 0.001). Catalase (CAT) was found to be significantly low in both groups (P < 0.001 in the PAP group (13.48 +/- 0.85 U/mg protein), P < 0.01 in the PAP + GSH group (18.75 +/- 1.17) as compared to the control group (41.03 +/- 0.93)). Glutathione peroxidase (GPx) in the PAP and PAP + GSH groups was found to be significantly high (P < 0.01 in the PAP group (5.32 +/- 0.033 U/mg protein), P < 0.001 in the PAP + GSH group (6.48 +/- 0.1)) as compared to the control group (2.93 +/- 0.093)). Similarly, glutathione reductase (GSSGR) in the PAP (0.023 +/- 0.002 U/mg protein), and PAP + GSH (0.025 +/- 0.001) groups was found to be significantly high as compared to the control group (0.014 +/- 0.001) (P < 0.001). GSH in the PAP (161.93 +/- 8.3 mg/mg protein) and PAP + GSH (170.7 +/- 4.51) groups were found to be significantly higher than the control group (104.91 +/- 3.0) (P < 0.001). Malondialdehyte (MDA) in the PAP (11.2 +/- 0.62 nmol/mg protein) and PAP + GSH (9.72 +/- 0.46) groups was found to be significantly higher than in the control group (5.54 +/- 0.51)(P < 0.001). Free radicals might have a major role in the PAP-induced nephrotoxicity. GSH increased nephrotoxicity.
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PMID:The role of free radicals in p-aminophenol-induced nephrotoxicity: does reduced glutathione have a protective effect? 881 62

We have isolated and conducted preliminary characterization of a cell line derived from the Chinese hamster ovary cell line AA8, which we have designated AG8 and which is highly resistant to the cytotoxic effects of H2O2 (approximately 17-fold when the H2O2 treatment was at 37 degrees; approximately 11-fold when the H2O2 treatment was at 4 degrees). AG8 cells were moderately (but significantly; P < 0.05) cross-resistant to CdCl2 (approximately 4-fold), NaAsO2 (approximately 2.3-fold), t-butyl hydroperoxide (approximately 2.9-fold), cumene hydroperoxide (approximately 3-fold), menadione (approximately 1.7-fold) and HgCl2 (approximately 1.5-fold), but were not significantly cross-resistant to hyperthermia (43 degrees), 254 nm UV light, 137Cs gamma-rays, and 42-MeV (p-->Be+) fast neutrons. As regards their biochemical status, AG8 and AA8 cells contain similar non-protein sulfhydryl levels per milligram of protein. Catalase activity (assessed by both spectrophotometry and polarography) was significantly higher in AG8 than in AA8 cells irrespective of whether enzyme activity was expressed per 10(6) cells (approximately 3.6-fold increase) or per milligram of protein (approximately 1.6-fold increase). AG8 cells also exhibited significantly greater glutathione reductase activity than wild-type cells when the data were expressed per 10(6) cells (approximately 2.9-fold) or per milligram of protein (approximately 1.3-fold). Glutathione peroxidase activity was immeasurably low in both cell lines. The susceptibility of the two cell lines to H2O2-mediated generation of DNA single-strand breaks (as measured by alkaline elution) indicated a slightly (approximately 1.5-fold) decreased yield in the resistant AG8 cell line. The two cell lines repaired these breaks with similar kinetics. In contrast, no measurable induction of DNA double-strand breaks (as measured by pulsed-field gel electrophoresis) was apparent in either cell line after survival-curve range concentrations of H2O2. On the basis of these data, it appears that the AG8 phenotype involves two previously identified resistance mechanisms, namely an adaptive component that may or may not involve increased antioxidant capacity, and a second component that does involve increased antioxidant (primarily catalase) capacity.
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PMID:Isolation and preliminary characterization of a Chinese hamster ovary cell line with high-degree resistance to hydrogen peroxide. 886 24

Antioxidant enzyme activities were measured following exposure to hypericin +/- irradiation in EMT6 cells. CuZnSOD and catalase activities peaked within 0.5 h following irradiation for nontoxic 0.5 microM hypericin and toxic 1.0 microM hypericin. Catalase remained elevated up to 3 h for 1.0 microM hypericin + light. MnSOD activity was elevated immediately following irradiation for both doses. These levels returned to control by 1 h for 0.5 microM hypericin, but were depressed after 1 h for 1.0 microM hypericin. This suggests that mitochondria impairment may be a critical factor in hypericin phototoxicity. Glutathione reductase was inhibited immediately following irradiation with 1.0 microM hypericin, suggesting that an altered status of the glutathione pool contributed to cytotoxicity. Glutathione peroxidase activities were elevated following irradiation but returned to control levels within 0.5 h for both doses, implicating hydroperoxide formation as an early event in hypericin phototoxicity. Inhibition by hypericin in the dark was demonstrated for purified CuZnSOD, Se-dependent glutathione peroxidase, glutathione S-transferase, and glutathione reductase activities in vitro. Irradiation did not potentiate hypericin-mediated glutathione reductase inhibition and decrease inhibition for the other enzymes. Collectively, these data demonstrate an antioxidant enzyme response to hypericin photoactivation and confirm a role for oxygen in hypericin phototoxicity.
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PMID:Antioxidant enzyme response to hypericin in EMT6 mouse mammary carcinoma cells. 958 12

Oxidative stress parameters were evaluated in rat testes after chronic iron intoxication and vitamin E supplementation. Male Wistar rats were fed during 6 weeks with the following diets: C = rat chow; I = C + 25 mg carbonyl-iron/g diet; A = C + 0.2 mg alpha-tocopheryl acetate/g diet; and the combination of I and A (IA). After the treatment, no changes in final body weight, testis weight and protein content were observed. Total iron content in testes from the I group was 33% higher compared to the C group (216 +/- 10 nmol/g of tissue). The content of alpha-tocopherol (alphaT) was 2.5-fold higher in the A and IA groups compared to the C group (12.8 +/- 0.7 nmol/g tissue). The content of ubiquinol-9 (13.0 +/- 1.7 nmol/g tissue) and ubiquinol-10 (3.3 +/- 0.5 nmol/g tissue) was similar among the groups. Superoxide dismutase activity was 13 and 16% lower in the A and IA groups with respect to the C group (12.9 +/- 0.7 U/mg protein). Catalase activity was 26 and 33% lower in the I and IA groups than in the C (0.19 +/- 0.01 pmol/mg protein) and A (0.21 +/- 0.01 pmol/mg protein) groups, respectively. Glutathione peroxidase was 24 and 23% higher in the IA group than in the C (11.4 +/- 0.3 mU/mg protein) and I (11.5 +/- 1.0 mU/mg protein) groups, respectively. The testes content of 2-thiobarbituric acid-reactive substances (TBARS) and protein-associated carbonyl groups were 37 and 16% higher, respectively, in the I group than in the C group. These increased in TBARS and carbonyls, were not observed in the IA group. No diet-associated changes were observed in the steady state levels of 8-oxo-2'-deoxyguanosine in testes DNA (4.2 +/- 0.2 residue/10(5) dG). The present data suggest that this model of chronic iron overload produced a mild oxidative damage in rat testes that was partially prevented by alphaT supplementation.
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PMID:Oxidative stress in testes of rats subjected to chronic iron intoxication and alpha-tocopherol supplementation. 1043 81

Glutathione peroxidase (GPX) activity measured using tert-butyl hydroperoxide as a substrate detects solely cellular/classical GPX (cGPX) in rat liver and kidney, and extracellular/plasma glutathione peroxidase (EC-GPX) in rat serum. To investigate the effect of peroxisome proliferator on EC-GPX, we measured activities of GPX and catalase in rat liver, kidney and serum, and then we performed immunoblot and Northern blot analyses in the kidney. Rats were fed on a diet containing either 2% (w/w) di-2-ethylhexyl phthalate (DEHP) or 0.25% (w/w) clofibrate for two or three weeks, respectively. Catalase activity was increased 1.4-fold (p < 0.001) in the treated liver, but not in the kidney. GPX activity was decreased to 59.2% (DEHP) and 70.4% (clofibrate) of the control (p < 0.001) in the serum but was unaltered in the liver and kidney. The immunoreactivity for EC-GPX was also significantly decreased in the DEHP-treated kidney compared with the control. The mRNA levels of EC-GPX and cGPX were unaltered. The immunostaining for 4-hydroxy-2-nonenal, a maker of lipid peroxide, was more intense in the treated kidney compared with the control. These results suggest that EC-GPX is post-transcriptionally decreased by peroxisome proliferator through the oxidative stress in the renal tubules. This may be a new deleterious effect of an endocrine disruptor DEHP.
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PMID:Effect of peroxisome proliferator on extracellular glutathione peroxidase in rat. 1049 74

Short-term effects of physiological concentrations of conjugated linoleic acid (CLA) on membrane integrity, metabolic function, cellular lipid composition, lipid peroxidation, and antioxidant enzymes were examined using rat hepatocyte suspension cultures. Incubation with CLA (5-20 ppm) for 3 h decreased the ability of hepatocyte plasma membranes to exclude trypan blue by approximately 25%, and caused leakage of cytosolic lactate dehydrogenase (LDH) into the medium. The significant decrease (P< 0.02) in hepatocyte viability as measured by LDH leakage during cell incubation with 10 and 20 ppm CLA was not associated with significant changes in cellular ATP content. Protein synthesis in hepatocytes was elevated (P < 0.05) in the presence of 5 and 10 ppm CLA, but at a higher concentration (20 ppm), protein synthesis was similar to that of control cells. Gluconeogenesis was maintained in cells incubated with lower concentrations of CLA (5 and 10 ppm) but was decreased (P < 0.02) at the higher concentration. Incubation with 20 ppm CLA for 3 h did not affect the specific activity of 3-hydroxy-3-methylglutaryl coenzyme A reductase, the rate-limiting enzyme of cholesterol synthesis. Both cis-9,trans-11/trans-9,cis-11, and cis-10,trans-12/trans-10,cis-12 isomers of CLA were incorporated to a similar level into hepatocytes. Levels ranged from 3.9 to 4.1%, respectively, of total fatty acids in neutral lipids, and from 0.7 to 0.8%, respectively, of total fatty acids in phospholipids. Cellular lipid peroxidation remained unchanged in the presence of CLA (5-20 ppm), despite significant inhibition (P < 0.05) of superoxide dismutase. Catalase activity was maintained near control levels in the presence of 5 and 10 ppm CLA but was significantly decreased in the presence of 20 ppm CLA. Glutathione peroxidase activity was significantly decreased in the presence of 10 ppm CLA. The apparent sensitivity of the antioxidant enzyme defense system of liver cells to CLA, coupled with the lack of effect of CLA on lipid peroxidation in cells, suggests that cytotoxic effects of CLA as described by LDH leakage and decreased gluconeogenesis were not mediated by a prooxidant action in hepatocytes.
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PMID:The effect of conjugated linoleic acid on the antioxidant enzyme defense system in rat hepatocytes. 1052 94

The deficiency of methionine, an essential amino acid, is associated with cardiovascular lesions. Because different types of cardiac pathologies are caused by a decrease in antioxidants, we examined the effects of methionine on myocardial antioxidant enzymes in hemodynamically assessed rats that were treated with methionine (10 mg/ml) in drinking water for 12, 24, and 48 h. Glutathione peroxidase (GSHPx) activity was significantly increased to 150.5 +/- 12.2 and 191.7 +/- 13.7% of the control value at 12 and 24 h, respectively, followed by a decline to 120 +/- 24.6% at 48 h. The mRNA levels of GSHPx at these time points were 151.2 +/- 12.0, 218.7 +/- 35.3, and 173.5 +/- 25.2%, respectively. Superoxide dismutase (SOD) activity was 144.3 +/- 3.7, 114.3 +/- 10.1, and 143.1 +/- 11. 2% at 12, 24, and 48 h, respectively. Catalase (Cat) activity was 272.4 +/- 5.4, 237.8 +/- 16.6, and 224.1 +/- 17.3% of the control value. The expression of Cat and SOD mRNA was unchanged at 12, 24, and 48 h. The lipid peroxidation was decreased by 24.4 +/- 11.2, 54. 9 +/- 0.1, and 6.4 +/- 2.1% at 12, 24, and 48 h, respectively. Methionine had no effect on the ventricular or aortic pressures, heart rate, and myocardial glutathione levels at any of the time points. The study shows that methionine has a significant effect on the myocardial antioxidant enzyme activities, and only changes in GSHPx enzyme activity correlated with the mRNA changes. These antioxidant changes may have a role in the beneficial effects of methionine in pathological rather than physiological conditions.
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PMID:Effects of methionine on endogenous antioxidants in the heart. 1060 Aug 29

Free radicals, hydroxyperoxides and H(2)O(2) are all known to damage cell components. This study was designed to compare the concentrations of hydroxyperoxide and free radical scavengers in the cardiac muscles of old rats in the hyper- or hypothyroid condition, to determine whether rates of peroxidation would differ with age, thyroid status, or both. Rats were rendered hyper- or hypothyroid by administration of l-thyroxine or methimazole for 4 weeks. Among the old rats, the lipid peroxide (LPO) concentrations, measured as thiobarbituric acid (TBA) reactants, were significantly greater in the hyperthyroid than in the euthyroid state and the LPO concentrations measured as TBA+Fe(3+) reactants, which may be precursors of LPO, were significantly greater in the hyperthyroid state, whereas in young rats, the LPO concentrations measured by TBA or TBA+Fe(3+) methods did not differ significantly in the hyperthyroid state. In the euthyroid state, the concentration of LPO measured as TBA+Fe(3+) reactants was significantly reduced with age. Xanthine oxidase (XOD) activity also was markedly increased with age, being more pronounced in the hyperthyroid than in the euthyroid state. The Mn and Cu/Zn superoxide dismutase activities were greater in the hyperthyroid than in the euthyroid state. Glutathione peroxidase activity decreased with age in the euthyroid and, particularly, in the hyperthyroid state. Catalase activity was not affected in the old rats. Concentrations of alpha-tocopherol in the old rats were high in the hyperthyroid state and low in the hypothyroid state, whereas the levels of beta- and gamma-tocopherols in these rats were unchanged in both conditions as compared with the euthyroid state findings. Data suggest that the site of free radical generation differs in older rats, with additional shifts in the location of intracellular lipid peroxidation being noted during hyperthyroidism. Thus, as rats age, the reduction of the free radical scavenger system and the increase in LPO and XOD activities might induce myocardial dysfunction.
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PMID:Lipid peroxidation levels in rat cardiac muscle are affected by age and thyroid status. 1060 42


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