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)

Glutathione (gamma-glutamylcysteinylglycine) is one of the major antioxidants in the body. The present study investigated the changes of glutathione status, oxidative injury, and antioxidant enzyme systems after an exhaustive bout of treadmill running and/or hydroperoxide injection in male Sprague-Dawley rats. Concentrations of total and reduced glutathione in deep vastus lateralis muscle were significantly increased (P less than 0.01) after exhaustive exercise with either hydroperoxide (t-butyl hydroperoxide) or saline injection, whereas hydroperoxide alone had no significant effect. Exhaustive exercise increased muscle glutathione disulfide content by 75 and 60% (P less than 0.05), respectively, in hydroperoxide and saline groups. Concentrations of glutathione-related amino acids glutamate, cysteine, and aspartate were significantly increased in the same muscle after exhaustion. Hepatic glutathione status was not affected by either hydroperoxide injection or exercise. Glutathione peroxidase, glutathione reductase, superoxide dismutase, and catalase activities were significantly elevated after exhaustive exercise with or without hydroperoxide injection in muscle but not in liver. Hydroperoxide and exhaustive exercise enhanced lipid peroxidation in muscle and liver, respectively. It is concluded that exhaustive exercise can impose a severe oxidative stress on skeletal muscle and that glutathione systems as well as antioxidant enzymes are important in coping with free radical-mediated muscle injury.
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PMID:Responses of glutathione system and antioxidant enzymes to exhaustive exercise and hydroperoxide. 155 31

Forty-three twin lamb fetuses of 121 +/- 1 d gestation were catheterized and received i.v. saline (n = 8), 0.75 mg/kg/h cortisol for 60 h (n = 15), 5 micrograms/kg thyrotropin-releasing hormone (TRH) every 12 h for five doses (n = 9), or cortisol and TRH (n = 11) before delivery at 128 +/- 1 d. After delivery, the lambs were randomized for natural sheep surfactant treatment or sham treatment, ventilated for 75 min, and killed. Superoxide dismutase, catalase, and glutathione peroxidase activities were measured in fetal lung tissue. Superoxide dismutase and catalase activities were increased in both the corticosteroid (p less than 0.001) and the corticosteroid with TRH (p less than 0.01) groups. Glutathione peroxidase activity was higher after prenatal corticosteroid treatment, but statistical significance was not reached (p = 0.06). Although prenatal exposure to corticosteroids increased superoxide dismutase, catalase, and glutathione peroxidase activities, TRH alone or TRH added to corticosteroids provided no additional benefit. Lambs treated with surfactant had higher lung catalase activities than lambs that did not receive surfactant, probably secondary to the presence of catalase activity in the surfactant preparation. Increased pulmonary antioxidant enzyme activity may be an additional feature of the overall beneficial effect of corticosteroids on fetal lung development.
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PMID:Corticosteroids, thyrotropin-releasing hormone, and antioxidant enzymes in preterm lamb lungs. 180 46

Maximal activities of antioxidant enzymes involved in oxygen free radical metabolism in skeletal muscle and liver were investigated in 4-, 26-, and 31-mo-old male Wistar-Furth rat at rest and after a single bout of treadmill exercise. In skeletal muscle, cytosolic (Cu-Zn) and mitochondrial (Mn) superoxide dismutase (SOD) specific activities were significantly higher in the aged rats and at 31 mo reached 135 and 218%, respectively, of those at 4 mo. Resting catalase activity was doubled at 31 mo compared with that at 4 mo. Glutathione peroxidase (GPX) activity increased twofold in muscle cytosol and by 47% in mitochondria of aged rats. Glutathione S-transferase (GST), glutathione reductase (GR), and glucose-6-phosphate dehydrogenase (G-6-PDH) activities in muscle were also significantly elevated. Hepatic antioxidant enzymes were altered differentially with aging. Cytosolic SOD and GST activities were decreased, whereas mitochondrial GPX, GR, and G-6-PDH activities were increased. Lipid peroxidation was greater in skeletal muscle homogenate and mitochondria but lower in liver homogenate in the aged rats. An acute exercise bout had little effect on muscle or liver antioxidant enzymes regardless of the animal's age. It is concluded that aging is accompanied with an elevation of antioxidant enzyme activities and lipid peroxidation in skeletal muscle probably due to the increased oxygen free radical production and reaction.
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PMID:Alteration of antioxidant enzymes with aging in rat skeletal muscle and liver. 233 Oct 35

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

Immunoperoxidase and immunogold techniques were used to localize the following antioxidant enzyme systems in the adult hamster kidney at the light and ultrastructural levels: superoxide dismutases, catalases, peroxidases and glutathione S-transferases. Each cell type in the kidney showed specific patterns of labelling of these enzymes. For example, proximal and distal tubular and transitional epithelial cells showed significant staining for all of these enzymes, while glomerular cells and cells of the thin loop of Henle did not show significant staining at the light microscope level. In addition, high levels of glutathione peroxidase were found in smooth muscle cells of renal arteries. At the ultrastructural level, each enzyme was found in a specific subcellular location. Manganese superoxide dismutase was found in mitochondria, catalase was localized in peroxisomes, while copper, zinc superoxide dismutase and glutathione S-transferase (liver and placental forms) were found in both the nucleus and cytoplasm. Glutathione peroxidase was found to have a broad intracellular distribution, with localization in mitochondria, peroxisomes, nucleus, and cytoplasm. Microvilli of tubular cells were labelled by antibodies to catalase, copper, zinc superoxide dismutase, glutathione peroxidase, and glutathione S-transferases. Cell types that were negative by light microscopy immunoperoxidase studies showed definite labelling with immunogold post-embedding ultrastructural techniques (glomerular cells and cells of the loop of Henle), demonstrating the greater sensitivity of the latter technique. These observations demonstrate that there are large variations in the levels of antioxidant enzymes in different cell types, and that even within a distinct cell type, the levels of these enzymes vary in different subcellular locations. Our results demonstrate for the first time the overall antioxidant enzyme status of individual kidney cell types, thereby explaining why different cell types have differing susceptibilities to oxidant stress. Possible physiological and pathological consequences of these findings are discussed.
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PMID:Immunolocalization of antioxidant enzymes in adult hamster kidney. 784 85

Intravenous administration of bacterial endotoxin (lipopolysaccharide: LPS) induces shock and disseminated intravascular coagulation in rats. Our report here shows that LPS-administered rats (10 mg/100 g) develop tissue injuries and functional disorders in multiple vital organs. In the present study, we investigated changes in tissue antioxidant enzyme activities, neutrophil sequestration, and lipid peroxides in multiple organs (lung, stomach, small intestine for antioxidant enzyme activities and neutrophil sequestration; lung, stomach, small intestine, liver, abdominal aorta for lipid peroxides) of LPS-treated rats. LPS-treated animals morphologically revealed pulmonary interstitial edema, alveolar hemorrhage, and mucosal hemorrhage in the small intestine 45 min after LPS administration. Blood samples withdrawn from LPS-treated animals exhibited increases in serum amylase, blood urea nitrogen, creatinine, and transaminase levels up to 180 min post-LPS infusion. LPS-treated animals showed a significant increase in tissue myeloperoxidase (MPO) activities of the lung, but not of the small intestine and stomach 45 min after LPS infusion. Thiobarbituric acid reactive substances (TBARS) in the lung, small intestine, stomach, liver, and abdominal aorta significantly increased at 45 min post-LPS-infusion. Tissue superoxide dismutase (SOD) activities of the LPS-treated animals demonstrated a significant decrease in the lung, which suffered from severe insults and neutrophil sequestration; no significant change in the small intestine, which suffered from morphological insults without neutrophil sequestration, and a significant increase in the stomach, which showed no histological impairment, at 180 min post-LPS administration. Glutathione peroxidase (GSH-PX) activities of the lung and small intestine showed no significant change in LPS-treated rats, while those of the stomach revealed a marked increase.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Changes in tissue antioxidant enzyme activities and lipid peroxides in endotoxin-induced multiple organ failure. 814 10

These experiments tested the hypothesis that high intensity (interval) training is superior to moderate intensity (continuous) exercise training in the upregulation of antioxidant enzyme activity in skeletal muscle. To test this postulate, we examined changes in oxidative and antioxidant enzyme activities in rat skeletal muscle following 12 wk of either interval (6 x approximately 5-min intervals at approximately 80-95% VO2max) or continuous (45 min at approximately 70% VO2max) exercise training. Both continuous and interval training resulted in significantly elevated (P < 0.05) succinate dehydrogenase (SDH) and 3-hydroxyacyl-CoA-dehydrogenase (HADH) activities in the gastrocnemius (G) and soleus (S) muscles compared with controls. SDH and HADH activities in the G and S muscles did not differ between the two exercise groups. Glutathione peroxidase (GPX) activity exceeded controls (P < 0.05) in only the interval trained S muscle. Soleus superoxide dismutase (SOD) activity was higher (P < 0.05) in both exercise groups compared with controls. No differences in SOD activity existed between interval and continuous trained animals. We conclude that when matched for oxygen cost, interval and continuous exercise training result in similar increases in SOD activity. However, high intensity interval exercise is superior to moderate intensity continuous exercise in the promotion of GPX activity in the S.
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PMID:High intensity training-induced changes in skeletal muscle antioxidant enzyme activity. 823 58

Antioxidant enzymes including catalase, superoxide dismutase, glutathione peroxidase, and glutathione S-transferases are thought to be the primary cellular defense against reactive oxygen species. Since pulmonary injury produced by oxidant air pollutants like ozone is highly focal, involving primarily the trachea and centriacinar areas of the lung, measurements of alterations in antioxidant enzyme activities in whole lung may substantially underestimate changes occurring in target areas of the respiratory tract. We have applied a technique for preparation of lung specimens from well-defined anatomic locations to determine whether the focal injury associated with ozone exposure is related to an uneven distribution of antioxidant enzyme activity in the respiratory tract. Our study compared enzyme activities in rat and monkey, species which differ considerably in sensitivity to ozone-induced injury (monkey > rat). The activities of glutathione S-transferase varied less than twofold between different airway subcompartments for both the rat and monkey. Pulmonary veins had approximately 50% of the activity of airways in both species. Glutathione peroxidase activity was slightly higher in proximal compared to distal airways of the rat but was evenly distributed at all airway levels in the monkey. In both species, activity in pulmonary veins was lower than that in airways. The activity of superoxide dismutase was similar in rat and monkey and marked differences were not observed in the various subcompartments studied. Similarly, catalase activity was relatively evenly distributed in rat airways but, in the monkey, the distal bronchiole and lobar bronchus had marginally higher activity than the trachea. We conclude that: (1) measurement of antioxidant enzyme activities in anatomic subcompartments within the lung is feasible using microdissected specimens, (2) antioxidant enzyme activity can vary in different subcompartments of the lung of the same species, (3) the pattern of variation in enzyme activity differs by the enzyme and by species, and (4) species and subcompartment differences in ozone injury are not due primarily to differences in the distribution of antioxidant enzyme activity.
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PMID:Variation in antioxidant enzyme activities in anatomic subcompartments within rat and rhesus monkey lung. 823 64

Using a sensitive Northern blot hybridization technique, gene expression of superoxide dismutase (SOD), catalase, and glutathione peroxidase was studied in pancreatic islets and for comparison in various other mouse tissues (liver, kidney, brain, lung, skeletal muscle, heart muscle, adrenal gland, and pituitary gland). Gene expression of the antioxidant enzymes was usually in the range of +/- 50% of that in the liver. Only in pancreatic islets gene expression was substantially lower. The levels of the cytoplasmic Cu/Zn SOD and the mitochondrial Mn SOD gene expression were in the range of 30-40% of those in the liver. Glutathione peroxidase gene expression was 15%, and catalase gene expression was not at all detectable in pancreatic islets. These low levels of antioxidant enzyme gene expression may provide an explanation for the extraordinary sensitivity of pancreatic beta cells towards cytotoxic damage by diabetogenic compounds and during the development of human and animal diabetes.
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PMID:Low antioxidant enzyme gene expression in pancreatic islets compared with various other mouse tissues. 872 Sep 19

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


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