Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:P30044 (antioxidant enzyme)
 8,037 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The effect of dietary copper (Cu) deficiency on the antioxidant enzyme superoxide dismutase (SOD) was investigated in both erythrocyte and liver samples of 40 weanling Wistar rats. Groups were fed control (10 mg Cu/kg) or Cu-deficient (0.5 mg Cu/kg) diets for 7 wk. In this study, dietary copper deficiency did not affect growth, food intake, liver size, or hemoglobin levels. Protein concentrations were considerably decreased in the livers of the copper-deficient group compared to control groups after 7 wk. Erythrocyte SOD activity was not significantly different in copper-deficient groups. In contrast, SOD activity was significantly reduced in livers of rats consuming the Cu-deficient diet compared to controls. The in vitro SOD activities in the presence of five different macro-cyclic copper-II containing complexes with different stability constants were studied. The moderately stable copper complex increased the SOD activity in Cu-deficient liver and erythrocyte samples only at wk 7. At wk 6, a significant increase in SOD activity in liver samples only was observed. In contrast, at wk 4, no significant differences in SOD activity were observed upon addition of Cu complexes. These results suggest that the increase in SOD activity may be due to superoxide-like action or other properties of this copper complex.
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PMID:Effects of copper deficiency and Cu complexes on superoxide dismutase in rats. 874 23

Twenty-two hypothalamic amenorrheic patients, who were non-smokers and of normal weight, received replacement therapy for 1 month with transdermal patches containing 8 mg estradiol. No other drugs were prescribed or taken during the study. Before treatment (time 0) and 1 month after its start, blood samples were taken for assay of plasma estradiol levels, the erythrocyte antioxidant enzyme activities of superoxide dismutase, catalase, glutathione peroxidase (GSH-Px), and an age-dependent erythrocyte enzyme activity, pyruvate kinase. Plasma malondialdehyde levels, as an index of lipoperoxidation products, were also detected. The results showed no significant variations in superoxide dismutase, catalase, pyruvate kinase erythrocyte enzyme activities or plasma malondialdehyde levels. A significant increase in plasma estradiol levels (time 0, 17.33 +/- 4.12 pg/ml; 1 month, 81.25 +/- 10.45 pg/ml; means +/- SD; p < 0.0001) and in GSH-Px erythrocyte activity (time 0, 11.97 +/- 2.31 IU/g hemoglobin; 1 month, 16.88 +/- 4.38 IU/g hemoglobin; p < 0.004) was found. Plasma estradiol levels correlated significantly with GSH-Px erythrocyte activity 1 month after therapy was begun (r = 0.776, p < 0.003). We suggest that estrogens restored to physiological plasma levels, stimulate erythrocyte antioxidant GSH-Px activity, improving the antioxidant power of amenorrheic patients.
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PMID:Changes in the erythrocyte antioxidant enzyme system during transdermal estradiol therapy for secondary amenorrhea. 886 89

The changes in red blood cell (RBC) lipid peroxidation [measured via the malonyl dialdehyde (MDA) concentration], reduced (GSH), and oxidized glutathione (GSSG) levels, hemoglobin (Hb) oxidation and antioxidant enzyme [catalase (Cat), glutathione peroxidase, and superoxide dismutase (SOD)] activities were studied in 45 pediatric patients with various glomerular diseases [minimal change nephrotic syndrome (MCNS) in relapse or in remission, lupus nephropathy (SLE), poststreptococcal glomerulonephritis (APSGN), IgA nephropathy (IGA gn)], and in 20 adult patients with IGA gn and also in 15 pediatric and 14 adult controls. The in vitro effects of hydrogen peroxide [acetyl phenylhydrazine (APH) test] on the GSH and Hb metabolisms were likewise investigated. There was an increased oxidative stress in MCNS with relapse, IGA gn, SLE gn, and APSGN, which could be detected in the GSH and Hb oxidation and in the lipid peroxidation on the peripheral RBC-s. The RBC SOD and Cat activities were significantly lower in all patients than in the controls. The RBC GSSG level was significantly elevated in all patients, with the exception of MCNS in remission. This stimulated a compensatory GSH production in MCNS with relapse and in IGA gn, but not in SLE or APSGN. The regeneration of GSH from GSSG was reduced in MCNS with relapse, SLE, and IGA gn, but not in APSGN. In remission, the GSH-GSSG redox system normalizes, but in vitro the APH test stimulates an intensive Hb oxidation. In conclusion, there is a correlation between the presence of active glomerular disease and the evidence of oxidative changes in the various parameters measured in peripheral RBCs.
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PMID:Oxidative stress and antioxidant defense mechanism in glomerular diseases. 895 40

Recently, it has been suggested that bilirubin may act as a potent biological chain-breaking antioxidant. To observe the effects of free bilirubin on antioxidant reactions in cumene hydroperoxide-treated erythrocytes (15 g hemoglobin/dl), we added bilirubin at four different concentrations (0.5, 1, 5, and 10 mg/dl). We measured the thiobarbituric acid-reactive substance and reduced glutathione levels, and some antioxidant enzyme activities, namely superoxide dismutase, catalase, and glucose-6-phosphate dehydrogenase. Thiobarbituric acid-reactive substance and chemiluminescent signals decreased during the incubation. Superoxide dismutase activities also decreased but not as much as in the control group. Glucose-6-phosphate dehydrogenase activities and reduced glutathione levels increased, but catalase activities remained the same as the control group. Our results suggest that bilirubin--in the concentrations we have used--partially prevented the oxidant effects of cumene hydroperoxide.
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PMID:The effect of bilirubin on lipid peroxidation and antioxidant enzymes in cumene hydroperoxide-treated erythrocytes. 987 96

Differences in the incidence of adverse drug reactions to trimethoprim-sulfamethoxazole and dapsone may result from differences in the formation, disposition, toxicity, and/or detoxification of their hydroxylamine metabolites. In this study, we examine whether differences in the biochemical processing of sulfamethoxazole hydroxylamine (SMX-NOH) and dapsone hydroxylamine (DDS-NOH) by erythrocytes [red blood cells (RBCs)] contribute to this differential incidence. The methemoglobin (MetHgb)-forming capacity of both metabolites was compared after a 60-min incubation with washed RBCs from four healthy human volunteers. DDS-NOH was significantly more potent (P =.004) but equally efficacious with SMX-NOH in its ability to form MetHgb. The elimination of potential differences in disposition by lysing RBCs did not change the MetHgb-forming potency of either hydroxylamine. At pharmacologically relevant concentrations, greater reduction to the parent amine occurred with DDS-NOH. Maintenance of MetHgb-forming potency was dependent on recycling with glutathione, but no difference in cycling efficiency was observed between DDS-NOH and SMX-NOH. In contrast, the pharmacodynamics of hydroxylamine-induced MetHgb formation were not changed by pretreatment with the glucose 6-phosphate dehydrogenase inhibitor epiandrosterone or by compounds that alter normal antioxidant enzyme activity. Methylene blue, which stimulates NADPH-dependent MetHgb reductase activity, decreased MetHgb levels but did not alter the differential potency of these hydroxylamines. DDS-NOH was also significantly more potent when incubated with purified human hemoglobin A0. Collectively, these data suggest that the inherently greater reactivity of DDS-NOH with hemoglobin, the greater conversion of DDS-NOH to its parent amine, and potential differences in disposition of hydroxylamine metabolites may contribute to the preferential development of dapsone-induced hemotoxicity and sulfamethoxazole-induced hypersensitivity reactions.
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PMID:Methemoglobin formation by hydroxylamine metabolites of sulfamethoxazole and dapsone: implications for differences in adverse drug reactions. 1002 31

Serum levels of total cholesterol, triglycerides, lipoproteins, lipid peroxides (TBARS) and erythrocyte antioxidant enzyme activities were measured in 105 non insulin dependent diabetic patients, among whom 38 had microvascular complications (MVC) of diabetes. All the diabetic patients had higher concentrations of glycated hemoglobin (HbA1) compared to controls (10.51 +/- 2.42% vs 6.31 +/- 0.85% P <0.001). Significant increase of serum triglycerides (TG), total cholesterol (TC), low density lipoprotein cholesterol (LDL-C) and very low density lipoprotein cholesterol (VLDL-C) and a significant decrease of high density lipoprotein cholesterol (HDL-C) were observed in the diabetic patients compared to controls (TG: 2.31 +/- 0.9 mmol/l vs 1.53 +/- 0.48 mmol/l P <0. 001; TC: 5.94 +/- 1.4 mmol/l vs 4.3 +/- 0.85 mmol/l P <0.001; LDL-C: 3.96 +/- 1.33 mmol/l vs 2.39 +/- 0.8 mmol/l P <0.001; VLDL-C: 0.46 +/- 0.2 mmol/l vs 0.3 +/- 0.09 mmol/l P <0.001; HDL-C: 0.81 +/- 0.24 mmol/l vs 1.04 +/- 0.18 mmol/l P <0.001). Significantly increased levels of serum TBARS were observed in diabetic patients compared to those in controls (TBARS: 6.7 +/- 1.5 mmol/l vs 5.14 +/- 0.61 mmol/l P <0.001). Erythrocyte catalase (CAT) activity was increased and Glutathione peroxidase (GPx) activity was decreased in diabetic patients compared to controls, but no significant change in Superoxide dismutase (SOD) activity was observed in diabetic patients (CAT: 104.94 +/- 37.1 KU/g Hb vs 85.8 +/- 23.6 KU/g Hb, P <0.01; GPx: 30 +/- 9.7 U/g Hb/min vs 40.84 +/- 12.3 U/g Hb/min, P <0. 001; SOD: 2.4 +/- 1.2 U/mg Hb/min vs 2.55 +/- 0.84 U/mg Hb/min, P=NS). In comparison with the diabetic group without MVC, the diabetic group with MVC had decreased GPx and SOD activities, while no difference was observed between these two groups regarding CAT activity (GPx: 25.32 +/- 8.4 U/g Hb/min vs 34.5 +/- 8.8 U/g Hb/min, P <0.001; SOD: 1.83 +/- 0.53 U/mg Hb/min vs 2.84 +/- 1.4 U/mg Hb/min, P<0.001; CAT: 106.3 +/- 39.9 KU/g Hb vs 103 +/- 34.9 KU/g Hb, P =NS). TBARS concentrations were significantly increased in the group with MVC compared to the group without these complications, indicating a positive relationship between TBARS and MVC of diabetes (7.05 +/- 1.23 mmol/l vs 6.3 +/- 1.02 mmol/l, P <0.001). Serum triglycerides, LDL and VLDL cholesterol concentration were significantly higher in diabetics with MVC than in diabetics without the complications (TG: 2.7 +/- 0.98 mmol/l vs 2.13 +/- 0.82 mmol/l, P<0.01; LDL - C: 4.45 +/- 1.3 mmol/l vs 3.67 +/- 1.3 mmol/l, P <0. 02; VLDL-C: 0.53 +/- 0.19 mmol/l vs 0.43 +/- 0.16 mmol/l, P <0.01), and the serum levels of TC in the group with MVC showed a positive correlation with their lipid peroxide levels (r =0.368, P <0.001). The increase in TBARS and the decreased GPx and SOD activities in diabetics with MVC in this study indicate that these factors may contribute to the occurrence of micro vascular complications in NIDDM patients.
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PMID:Lipid peroxidation and antioxidant enzyme levels in type 2 diabetics with microvascular complications. 1111 18

We have previously demonstrated that the loss of glutathione (GSH) and GSH-peroxidase (GSH-PX) in banked red blood cells (RBCs) is accompanied by oxidative modifications of lipids, proteins and loss of membrane integrity. The objective of this study was to determine whether artificial increases in antioxidant (GSH) or antioxidant enzyme (catalase) content could protect membrane damage in the banked RBCs following an oxidant challenge. RBCs stored at 1-6 degrees C for 0, 42 and 84 days in a conventional additive solution (Adsol) were subjected to oxidative stress using ferric/ascorbic acid (Fe/ASC) before and after enriching them with GSH or catalase using a hypotonic lysis-isoosmotic resealing procedure. This lysis-resealing procedure in the presence of GSH/catalase raised intracellular GSH and catalase concentrations 4-6 fold, yet produced only a small reduction in mean cell volume (MCV), mean cell hemoglobin (MCH) and mean cell hemoglobin concentrations (MCHC). Indicators of oxidative stress and membrane integrity were measured, including acetylcholinesterase (AChE) activity, GSH concentration, phosphatidylserine (PS) externalization (prothrombin-converting activity) and transmembrane lipid movements (14C-lyso phosphatidylcholine flip-flop and PS transport). GSH-enrichment protected AChE activity in fresh (0 day) and stored (42 and 84 days) RBCs from Fe/ASC oxidation by 10, 23 and 26%, respectively, compared with not-enriched controls. Following oxidative stress, the rate of transbilayer lipid flip-flop did not increase in fresh cells, but increased 9.3% in 42-day stored cells. Phosphatidylserine exposure, as measured by prothrombinase activity, increased 2.4-fold in fresh and 5.2-fold in 42-day stored cells exposed to Fe/ASC. Previous studies have shown that 42-day storage causes a moderate decrease in PS transport (approximately 50%), whereas transport rates declined by up to 75% in stored RBCs when challenged with Fe/ASC. GSH-enrichment prevented the increase in passive lipid flip-flop and the increase in prothrombinase activity, but offered no protection against oxidative damage of PS transport. In contrast to these effects, catalase-enrichment failed to protect GSH levels and AChE activity upon oxidative stress. Membrane protein thiol oxidation was assessed by labeling reactive protein thiols with 5-acetalamidofluorescein followed by immunoblotting with antifluorescein antibodies. Significant oxidation of membrane proteins was confirmed by a greater loss of thiols in stored RBCs than in fresh RBCs. These results demonstrate that it may be possible to prevent storage-mediated loss of AChE, increased lipid flip-flop, and increased PS exposure, by maintaining or increasing GSH levels of banked RBCs.
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PMID:Glutathione loading prevents free radical injury in red blood cells after storage. 1120 85

We measured the activities of erythrocyte superoxide dismutase (SOD) and glutathione peroxidase (GPX) before therapy in 97 patients with cancer in various sites (gastrointestinal tract (GIT) (n=40), breast (n=30), and others (n=27)), and in 60 matched controls to assess antioxidant enzyme protection. Hemolysate hemoglobin (Hb) was measured spectrophotometrically. The activity of SOD (U/g Hb) was significantly lower in all sites (when all the cancer sites were considered as a group), GIT, breast, and other sites compared to the controls (P<0.0001, P<0.0001, P<0.0001 and P<0.0001, respectively). The activity of GPX (U/g Hb) was significantly decreased in all sites, GIT, and breast cancer sites than in the controls (P=0.024, P=0.033, and P=0.043, respectively). Age showed a weak negative correlation with enzyme activities in controls and patients. There was no significant association between SOD and GPX activities in either the controls or the patients. These results suggest that there may be a greater antioxidant burden for SOD than GPX in cancer, and that a weak association exists between the activities of the two enzymes in antioxidant protection.
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PMID:Activities of erythrocyte antioxidant enzymes in cancer patients. 1211 88

The aim of this study was to examine solvent-associated effects on blood cytokine levels, antioxidant enzyme activities, and malondialdehyde (MDA) concentration in house painters. Trace element (Cu and Zn) and nitrite and nitrate levels as well as protein concentrations in erythrocytes and serum were determined. Thirty male house painters and 30 male clerical workers were included in the study. There were 13 smokers and 17 nonsmokers in each group. Hemoglobin concentrations were significantly lower in house-painter blood compared to controls. House painters had significantly higher concentrations of erythrocyte protein (excluding hemoglobin), whereas no significant difference was observed between serum protein levels. Proinflammatory cytokine levels, such as tumor necrosis factor-alpha and interleukin-8, were significantly increased in house painters' sera. Interleukin-6 was below the detection limit of the assay in both groups. Interleukin-1beta and cytokine receptor interleukin 2R concentrations were not significantly affected. Furthermore, a three- to fourfold increase in nitrite and nitrate concentrations was found in house painters' sera. Serum superoxide dismutase (SOD) and glutathione peroxidase (GSHPx) activities were significantly lower in house painters compared to controls. Malondialdehyde (MDA) concentration, a measure of lipid peroxidation, was found to be significantly elevated. In house painters, erythrocyte carbonic anhydrase and catalase activities were elevated approximately 11- fold and 2-fold, respectively. Zinc levels were significantly decreased in house painters' sera. Smoking was not found to be a major confounder for the association between solvent exposure and blood parameters.
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PMID:Effects of long-term solvent exposure on blood cytokine levels and antioxidant enzyme activities in house painters. 1216 7

Oxidative stress has been proposed as a pathogenic mechanism of atherosclerosis, cell aging, and neurologic disorders in Down syndrome. This study demonstrates a systemic decrease of all glutathione forms, including glutathionyl-hemoglobin, in the blood of children with Down syndrome. Furthermore, we obtained a disequilibrium, in vivo, between the antioxidant enzyme activities.
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PMID:Glutathione metabolism and antioxidant enzymes in children with Down syndrome. 1275 95


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