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)

Effects of high cholesterol diet (0.5% and 1%) on the activity of antioxidant enzymes [superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GSH-Px)] in the aortic tissue of rabbits were investigated in the absence or presence of probucol (0.5 gm/kg daily, orally). Five groups of ten rabbits each were studied. Group I, regular rabbit chow diet; Group II, chow + 0.5% cholesterol; Group III, chow + 0.5% cholesterol+probucol; Group IV, chow + 1% cholesterol and Group V, chow + 1% cholesterol+probucol. The aorta was removed at the end of 4 months for measurement of the antioxidant enzymes. An increase in activity of aortic antioxidant enzymes was noted in cholesterol-fed rabbits (Groups II and IV), being similar for SOD and catalase but higher for GSH-Px in Group IV as compared to Group II. Probucol was ineffective in altering this cholesterol-induced increase in enzyme activity except in Group III where it increased the activity of GSH-Px. These results suggest that aortic antioxidant enzymes are affected in hypercholesterolemia and that probucol is ineffective in altering the aortic antioxidant enzyme activity except GSH-Px activity which increased in 0.5% cholesterol-fed rabbits. The protective effects of probucol against hypercholesterolemic atherosclerosis may be partly due to an increase in the GSH-Px activity at low levels of hypercholesterolemia. At higher levels of hypercholesterolemia, the protective effects of probucol could be due to its antioxidant activity.
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PMID:Effects of probucol on hypercholesterolemia-induced changes in antioxidant enzymes. 856 23

We compared oxidant-induced intracellular adenine nucleotide catabolism and cell membrane injury in 4 different human cell types. Responses to oxidant exposure were correlated with endogenous antioxidant enzyme activities in these cells. Blood monocytes, amniotic fibroblasts, umbilical vein endothelial cells in primary culture, and transformed bronchial epithelial cells (BEAS 2B) were exposed to 0.1-5 mM hydrogen peroxide (H2O2) for 4 h. Some experiments were conducted in cells pretreated with 3-amino 1:2,4-triazole (ATZ) to inactivate catalase or with 1,3-bis(2-chloroethyl)-1-nitrosourea (BCNU) to inactivate glutathione (GSH) reductase. Depletion of adenine nucleotides and accumulation of their catabolic products (hypoxanthine, xanthine and uric acid) occurred to varying extent, monocytes being the most resistant. There was a mutual relationship between catalase and GSH reductase activities and maintenance of cellular adenine nucleotide levels during H2O2 exposure. GSH reductase inhibition rendered BEAS 2B cells susceptible to lytic injury by H2O2, assessed by release of lactate dehydrogenase and intact nucleotides into the medium, there was no correlation between these markers of such injury and endogenous antioxidant enzymes. We conclude that adenine nucleotide depletion and nucleotide catabolite accumulation relate closely with the antioxidant enzyme activities, whereas the lack of a similar correlation between the enzyme levels and markers of lytic cell injury suggest that intracellular antioxidant enzymes do not protect cells from membrane damage due to extracellular oxidants.
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PMID:Intracellular high energy metabolite depletion and cell membrane injury with antioxidant enzymes during oxidant exposure in vitro. 865 Jun 98

Recently there has been growing interest in magnesium deficiency and its correlation with coronary artery disease, chronic complications of diabetes mellitus and antioxidant enzyme activity. Hypomagnesemia is a common association of diabetes mellitus, and the blood glutathione (GSH) level is significantly lower in both conditions. Metformin (Met), 'an oral antihyperglycemic drug' frequently used in the management of diabetes mellitus outside the USA, has been shown to have an insulin-like action. The purpose of this study was to investigate the effect of oral administration of Met (60 mg kg(-1)) for 14 days on GSH and magnesium levels in blood, liver and heart of normal and streptozotocin-induced diabetic Wistar rats. Diabetes was induced by an i.p. injection of streptozotocin (60 mg kg(-1)). Our results showed that Met did not affect fasting serum glucose concentration in non-diabetic animals but reduced it significantly in diabetic animals. Serum and liver magnesium levels were significantly decreased in the untreated diabetic group compared with the normal group. Treatment with Met improved liver magnesium concentration in the diabetic group only. It has no effect on serum magnesium in diabetic or non-diabetic rats. Heart magnesium levels showed non-significant changes in all groups. In diabetic animals a significant decrease of GSH in both blood and liver was observed. Treatment with Met increased these levels significantly, with a similar effect on GSH levels in non-diabetic rats. There were no significant changes in heart GSH levels in any of the groups. This study demonstrates that oral Met therapy improves the altered levels of magnesium and GSH in diabetic rats.
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PMID:Effect of metformin on glutathione and magnesium in normal and streptozotocin-induced diabetic rats. 866 22

The influences of food deprivation and refeeding on glutathione (GSH) status, antioxidant enzyme activity and lipid peroxidation in response to an acute bout of exercise were investigated in the liver and skeletal muscles of male Sprague-Dawley rats randomly divided into three groups: starved for 48 h without refeeding; starved for 48 h and refed for 24 or 48 h. Half of each group of rats was exercised on a treadmill until exhaustion and killed immediately, whereas the other half group was killed at rest. Food-deprived rats had significantly lower liver GSH concentration and GSH:glutathione disulfide (GSSG) ratio. Malondialdehyde concentrations in the liver and skeletal muscle were both higher in the starved than in the refed rats (P < 0.05). Refed rats had significantly greater liver GSH level, gamma-glutamylcysteine synthetase and glucose 6-phosphate dehydrogenase activities and plasma insulin concentration than unfed rats. Exercised 24- and 48-h refed rats had 27% and 31 % lower liver GSH (P < 0.05), respectively, and a 21 % lower GSH:GSSG ratio (P < 0.05) than their rested counterparts. Plasma insulin concentrations were significantly lower, whereas glucagon concentrations were greater in the exercised than in the rested rats. Muscle GSH concentration was significantly lower in the food-deprived than in the refed rats (P < 0.05) but was unaffected by exercise. Exercised 24-h refed rats had significantly elevated muscle GSSG concentration compared with rested rats, along with a higher GSH peroxidase and a lower gamma-glutamyltranspeptidase activity (P < 0.05). These data indicate that both food deprivation-refeeding and exhaustive exercise influence liver and skeletal muscle glutathione status and that these changes may be controlled by hepatic glutathione synthesis and release due to hormonal stimulation.
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PMID:Alteration of glutathione and antioxidant status with exercise in unfed and refed rats. 868 45

The present study used male Sprague-Dawley rats to investigate changes in glutathione [reduced (GSH) and oxidized GSH (GSSG)]. lipid peroxidation (as indicated by tissue levels of malonaldehyde and 4-hydroxyalkenals), and the activity of the antioxidant enzyme glutathione peroxidase after a bout of swimming (30 min.) with or without melatonin (N-acetyl-5-methoxytryptamine) treatment. In muscle, the concentration of GSH and the GSH/GSSG ratio were decreased following 30 min. of swimming: these changes are indicative of enhanced oxidative stress. Pretreatment with melatonin prevented these effects. In liver, swimming increased significantly both GSH and GSSG, and decreased the GSH/GSSG ratio. When animals were treated with melatonin, concentrations of GSH and GSSG were also increased after swimming: however, the reduction in the GSH/GSSG ratio was prevented by melatonin. Brain GSH/GSSG ratio was not affected by exercise or by melatonin. Swimming enhanced the levels of lipid peroxidation products is muscle: this was prevented in animals treated with melatonin. Glutathione peroxidase activity was significantly elevated after swimming in both liver and brain with the change not being influenced by concurrent melatonin treatment. It is concluded that swimming imposes an oxidative stress on liver and skeletal muscle and the results show that melatonin confers partial protection against oxidative toxicity, especially in muscle.
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PMID:Tissue changes in glutathione metabolism and lipid peroxidation induced by swimming are partially prevented by melatonin. 873 65

Increased exposure to oxidant-derived free radicals or inadequate systems for antioxidant defense could alter cellular response at critical points in development. We measured 5 antioxidant enzymes, glutathione peroxidase (GSH-Px), glutathione reductase, glutathione-S-transferase, catalase and superoxide dismutase in erythrocytes and their plasma cofactor trace elements (Se, Zn, Cu) in 37 children with myelomeningocele and in 37 age-matched controls. We placed the patients into 3 groups according to motor level of the lesion at birth. We found significantly lower GSH-Px activities (p = 0.007) in children with myelomeningocele. For paired comparisons among the 3 patient groups and controls, there were significant differences (p < 0.05) between controls and both high (thoracic) and raid (lumbar) level embryologic lesions. The finding of antioxidant enzyme variations in our patients with myelomeningocele may indicate a role for abnormal oxidative metabolism in the development of this defect. The contribution of oxidative stress to human birth defects warrants investigation. We discuss potential relationships between oxidative stress and energy metabolism during primary neurulation.
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PMID:Comparison of erythrocyte antioxidant enzyme activities and embryologic level of neural tube defects. 877 May 69

Heart and red blood cell endogenous antioxidant status and plasma lipids were investigated in hypertensive, 14-week-old spontaneously hypertensive rats (SHR) and normotensive Wistar-Kyoto (WKY) rats fed a standard commercial rat chow. Specific heart and red blood cell antioxidant enzyme activities, as well as the susceptibility of tissues to H2O2-induced glutathione (GSH) depletion and lipid peroxidation, were measured. Systolic blood pressure in SHR was greater than in WKY rats at 13 weeks of age (197 +/- 12 vs. 132 +/- 14 mmHg (1 mmHg = 133.3 Pa); p < or = 0.05), confirming the presence of hypertension in SHR. Red blood cell catalase (CAT) and superoxide dismutase (SOD) activities were greater (p < or = 0.05) in SHR than WKY rats. Red blood cell CAT activity was positively correlated (r = +0.634; p = 0.026) with SOD, which in turn was correlated (r = +0.709; p = 0.049) with systolic blood pressure. Heart SOD activity was higher (p < or = 0.05) in SHR, while glutathione reductase (GSSG-Red) activity was lower (p < or = 0.05) than in WKY rats. This reduced ability to recycle GSH in the heart coincided with greater (p < or = 0.05) levels of H2O2-induced lipid oxidation products in SHR. Plasma total cholesterol and triacylglycerol levels were lower (p < or = 0.05) in SHR than WKY rats, with no visible signs of atherosclerosis in either SHR or WKY rats. In summary, hypertension in SHR was associated with alterations in antioxidant enzyme profiles of red blood cells and heart, with the latter showing an increased susceptibility to in vitro lipid oxidation. Although hypertension is a recognized factor in the development of human atherosclerosis, spontaneously hypertensive rats did not exhibit signs of aortic plaque, reflecting the resistance of this species to the development of atherosclerosis.
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PMID:Heart and red blood cell antioxidant status and plasma lipid levels in the spontaneously hypertensive and normotensive Wistar-Kyoto rat. 877 9

The effect of sulphur mustard (0.5 LD50, percutaneous) on antioxidant enzymes (superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GSH-Px)) in blood cells (erythrocytes (RBC), leucocytes (WBC) and platelets) and body tissues (liver, kidney, spleen and brain) of rats has been investigated 24 h post exposure. The SOD activity was significantly decreased in WBC, platelets, spleen and brain as compared to control. The CAT activity was significantly inhibited in RBC, WBC and spleen as compared to control. The GSH-Px activity was signficantly depressed in WBC, spleen and liver as compared to control. It is concluded that sulphur mustard at a sublethal dose inhibited antioxidant enzyme activities in WBC and spleen. Thus, antioxidant enzymes in lymphatic tissues may be used as suitable models for assessing mustard toxicity. The study suggests the formation of reactive oxygen species in sulphur mustard intoxication.
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PMID:Effect of topically applied sulphur mustard on antioxidant enzymes in blood cells and body tissues of rats. 881 65

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

This study investigates the changes in renal antioxidant system after cisplatin administration and the nephroprotection with 4-methylthiobenzoic acid (MTBA). Male Wistar rats were injected with (1) vehicle control, (2) cisplatin, (3) MTBA, and (4) cisplatin plus MTBA. Rats were euthenized 3 days post-treatment and kidney was isolated and analyzed for platinum concentration, malondialdehyde (MDA), glutathione (GSH and GSSG), superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GSH-Px). Plasma creatinine increased 508% following cisplatin administration alone, which decreased to 189% with MTBA. Cisplatin-treated rats showed a depletion of renal GSH levels (53%), while cisplatin plus MTBA-injected rats had GSH values close to those of the controls. SOD, CAT, and GSH-Px activities decreased 36, 29, and 38%, respectively, and MDA levels increased 212% following cisplatin administration, which were restored to control levels after MTBA treatment. The renal platinum level depleted significantly with MTBA treatment. The data suggest that cisplatin nephrotoxicity is mediated by depletion in GSH concentration and by impaired activities of SOD, CAT, and GSH-Px, increased lipid peroxidation, and plasma creatinine levels. The protection offered by MTBA against cisplatin nephrotoxicity is related to the reduction in plasma creatinine levels, prevention of GSH depletion and lipid peroxidation, and restoring antioxidant enzyme activity in the kidneys of rats.
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PMID:4-methylthiobenzoic acid protection against cisplatin nephrotoxicity: antioxidant system. 892 31


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