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)

Polyclonal antisera to manganese and copper-zinc superoxide dismutases, catalase, glutathione peroxidase (GPx), and isozymes of glutathione S-transferase (liver and placental isolates, GST-L and GST-P, respectively) were used to localize these enzymes in normal rat lung by immunostaining. Light-microscopic results, using an immunoperoxidase technique, were expanded on by electron-microscopic immunogold localization. The findings were consistent with previous biochemical work. However, both GPx and GST-P were predominantly localized to extracellular connective tissue of the lung. These findings demonstrate the basal antioxidant enzyme phenotypes for parenchymal lung tissue at light- and electron-microscopic levels. Significant components of enzymatic defense to oxidant stress are heterogeneously distributed throughout rat lung tissue including both epithelial cell surfaces and the extracellular matrix.
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PMID:Immunolocalization of antioxidant enzymes and isozymes of glutathione S-transferase in normal rat lung. 128 3

Influences of dietary selenium (Se) deficiency, physical training and an acute bout of exercise on myocardial antioxidant enzyme activity, lipid peroxidation and related biochemical properties were investigated in post-weanling male Sprague-Dawley rats. An experimental group was fed a diet containing less than 0.01 mg Se/kg and had free access to distilled water (Se-D), whereas control rats were supplemented with 0.5 mg Se/l in drinking water (Se-A). Se deficiency depleted heart mitochondrial and cytosolic Se-dependent glutathione peroxidase activity to 24 and 3%, respectively, of those in Se-A rats. Heart mitochondrial superoxide dismutase (Mn SOD) activity was 24% higher (p less than 0.05) in Se-D than in Se-A rats. Cytosolic (copper-zinc) SOD and catalase activities were not altered, whereas glutathione S-transferase activity was significantly decreased in Se-D (p less than 0.01). Myocardial antioxidant enzyme activities were not affected by either training or an acute exercise bout. Heart lipid peroxidation and activities of several enzymes in substrate metabolism were also unaffected by Se or exercise. It is concluded that rat heart has sufficient reserve of antioxidant enzyme capacity in coping with oxidative stress imposed by Se deficiency or exercise. The adaptation of Mn SOD may reveal its potential role in myocardial antioxidant defense.
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PMID:Antioxidant enzyme response to selenium deficiency in rat myocardium. 153 41

HA-1 hamster fibroblasts receiving fresh media every 24 h were continuously passaged in progressively increasing O2 concentrations for 18 mo (designated O2R95). These cells were significantly more resistant than parental HA-1 to clonogenic inactivation mediated by 95% O2 without media replacement. The O2R95 cell line exhibited increases in the activities of catalase (CAT), Mn superoxide dismutase (MnSOD), Cu,Zn superoxide dismutase (Cu,Zn SOD), and glutathione peroxidase (GPx). O2R95 cells demonstrated uniformly distributed increased staining for CAT, MnSOD, Cu,Zn SOD, and GPx proteins, as determined by immunohistochemistry. Cellular resistance to and metabolism of 4-hydroxy-2-nonenal (4HNE), a toxic byproduct of lipid peroxidation implicated in mechanisms of O2 toxicity, was examined in HA-1 and O2R95 cell lines. O2R95 cells were significantly more resistant to 4HNE cytotoxicity, which was accompanied by a significant increase in 4HNE metabolism. O2R95 cells also demonstrated an increase in total glutathione (GSH) and glutathione S-transferase (GST) activity, an enzymatic system believed to be involved with 4HNE metabolism. Furthermore, homogenates from O2R95 cells consumed greater quantities of 4HNE in the presence of NADPH (but not NADH, NAD+, or NADP+), suggesting that an enzyme(s) utilizing NADPH contributes to 4HNE metabolism, resistance to 95% O2 and 4HNE as well as increased total GSH, antioxidant enzyme activities, and NADPH-dependent metabolism of 4HNE, persisted in O2R95 cells for 75 days of growth in 21% O2. These findings are compatible with the hypothesis that aldehydic byproducts of lipid peroxidation contribute to mechanisms of O2 toxicity and the selective pressure exerted by exposure of cells to hyperoxia.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:A stable O2-resistant cell line: role of lipid peroxidation byproducts in O2-mediated injury. 161 58

We examined the influence of dehydroepiandrosterone (DHEA), a beta-agonist, and exercise training on enzymes that detoxify toxic oxygen species. Feeding 0.4% DHEA decreased hepatic cytosolic (c) selenium-dependent glutathione peroxidase (GPX), (-26%, P less than 0.0001) and increased hepatic mitochondrial (m) Mn superoxide dismutase (SOD), (+38%, P less than 0.001). DHEA decreased myocardial c-GPX (-21%, P less than 0.05) when compared to a beta-agonist (beta A; L644969 Merck and Co.) fed at 5 ppm but neither differed from the Control (C). In contrast, the beta A increased hepatic m-GPX (+25%, P less than 0.05). In skeletal muscle, DHEA and beta A decreased muscle c-GPX by 20 and 12%, respectively (P less than 0.0009). DHEA increased both muscle (+20%, P less than 0.01) and myocardial (+20%, P less than 0.05) c-glutathione S-transferase (GST) over beta A (+20%, P less than 0.01) but neither was significantly different from C. Similar to DHEA, chronic training (Tr) (1 h/day, 5 days/week at 27 m/min, 15% grade on treadmill) decreased hepatic c-GPX (-16%, P less than 0.003). Tr elevates muscle c-GPX (+36%, P less than 0.05) in C. Tr increased myocardial c-GPX by 28% in the beta A-treated rats, whereas Tr decreased myocardial c-GPX by 22% in the C (P less than 0.05, interaction). One hour of acute exercise (Ex) (70% VO2 max relative work load) decreased hepatic homogenate catalase (-12%, P less than 0.02) and increased hepatic m-Mn SOD (+28%, P less than 0.03). Ex decreased myocardial c-GST (P less than 0.05) only in the DHEA-treated rats. DHEA and Tr may improve efficiency of oxygen utilization at the tissue level with lower antioxidant enzyme activity in liver and locally protective up-regulation in muscle. beta A stresses oxygen utilization systems and liver responds by up-regulation of antioxidant enzymes. The increase in myocardial c-GPX activity in the beta A-treated group may be a protective effect against indirect catecholamine-induced myocardial necrosis which results from free radical generation.
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PMID:Dehydroepiandrosterone and a beta-agonist, energy transducers, alter antioxidant enzyme systems: influence of chronic training and acute exercise in rats. 198 Apr 4

The human hepatoma cell line Hep 3B, which has the hepatitis B virus genome, shows over 80% decrease of copper/zinc superoxide dismutase activity, over 90% decrease of manganese superoxide dismutase activity, over 70% decrease of catalase activity, absence of glutathione peroxidase and glutathione S-transferase activities, over 270-fold increase of ferritin content and 25-fold increase of total iron compared to normal autopsy liver. These conditions of low antioxidant enzyme activities and iron overload are those which support the accumulation of oxygen free-radicals and DNA damage commonly considered to be carcinogenic mechanisms.
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PMID:Antioxidant systems in tumour cells: the levels of antioxidant enzymes, ferritin, and total iron in a human hepatoma cell line. 350 92

Exposure of several different animal models to O2-induced lung injury has revealed marked differences in sensitivity of various species to O2 damage. These differences may be due in part to variation of cellular antioxidant defenses. To characterize lung antioxidant enzyme activities in different species, we measured lung activities of glutathione peroxidase (GSH-Px), superoxide dismutase (SOD), catalase (CAT), and glutathione S-transferase (GSH S-trans) in rat, hamster, baboon, and human lung. Soluble lung fractions were also fractionated on Sephadex G-150-S columns and GSH-Px activity was measured using both cumene hydroperoxide and H2O2. This was done to evaluate non-Se-dependent GSH-Px activity in these lung samples. Human lung was obtained at surgery from patients undergoing lobectomy or pneumonectomy for localized lung tumors. SOD activity was similar for all four groups. GSH-Px activity was higher in rat lung than baboon or hamster lung. Lung CAT activity was variable with the highest activity present in the baboon which revealed a lung CAT activity 10 times higher than activity present in the rat. Lung GSH S-trans activities were higher in hamster, baboon, and human lung than in rat lung. Non-Se-dependent GSH-Px was present in rat lung but absent in hamster, baboon, and human lung. We conclude that the hamster was the best model of the animals studied for mimicking human lung antioxidant enzyme activities. Rat lung antioxidant enzyme activities were markedly different from any of the other species examined.
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PMID:Species variation in lung antioxidant enzyme activities. 365 19

We have previously identified and characterized GSHPx-GI, which is a cellular selenium-dependent glutathione peroxidase (GSHPx) distinct from the classic GSHPx-1 and phospholipid hydroperoxide glutathione peroxidase (PHGPX). We have determined the level of GSHPx-GI mRNA expression in the rat gastrointestinal tract from esophagus to colon. Although GSHPx-GI mRNA is readily detectable throughout the GI tract, the highest level is detected in the ileum and cecum. We have also determined the levels of GSHPx-GI mRNA expression and several antioxidant enzyme activities along the villus-to-crypt axis in the rat small intestine by cell fractionation. GSHPx-GI mRNA is present at a similar level in all of the epithelial fractions, whereas GSHPx-1 mRNA is detectable only in the remnant. This suggests that GSHPx-GI is the major cellular tetrameric GSHPx expressed in intestinal epithelium, and the expression of GSHPx-GI in the GI tract is not likely regulated differentially through maturation of epithelial cells. In terms of enzymatic activity, although we detected lower glutathione S-transferase activity in the crypt epithelium, there was a marginal increase of PHGPX activity, a twofold increase of GSHPx activity, and a three- to fivefold increase of catalase activity in the crypt relative to the distal villus. Thus, the crypt epithelial cells may be better protected from peroxidative damage.
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PMID:The expression of an intestinal form of glutathione peroxidase (GSHPx-GI) in rat intestinal epithelium. 748 90

The effect of ozone on the respiratory system is not confined to a single region or a specific cell type. Ozone-induced injury can occur at all levels of the respiratory system. However, the effects of this oxidant gas throughout the tracheobronchial tree and the lung parenchyma can be highly variable. The doses of ozone delivered to the various regions may also be different, and these differences may have a significant effect on the extent of injury. To examine the effects of chronic exposure to ozone on the lungs, we used a systematic sampling approach to perform morphometric, histochemical, and enzymatic analyses of selected airway generations and pulmonary acini arising from short and long airway paths of the tracheobronchial tree. The objectives of this study were to define compositional, cytochemical, and architectural changes that occur in epithelial cells of the airways and major tissue components of the pulmonary acini after 20 months of exposure to 0.0, 0.12, 0.5, or 1.0 parts per million (ppm)* ozone in male and female F344/N rats. We found in the trachea and bronchi significant alterations in stored secretory product following exposure to ozone, but no changes in epithelial thickness or the volume density of nonciliated cells. The volume density of nonciliated cells was significantly increased in terminal bronchioles arising from a long airway path (caudal region) of the left lung. The predominant change within the pulmonary acini was the extension of bronchiolar epithelium beyond the bronchiole-alveolar duct junction into alveoli. This change was concentration-dependent and site-specific, with ventilatory units arising from a short path (cranial region) of the left lung in male rats being most affected. The antioxidant enzymes superoxide dismutase, glutathione peroxidase, and glutathione S-transferase were significantly elevated in the distal bronchiole to central acinus following 20 months of exposure to 0.5 or 1.0 ppm ozone. Changes in antioxidant enzyme levels were more variable in other airway generations. We conclude that the effects of long-term (20-month) exposure to ozone are dose-dependent and site-specific along the tracheobronchial tree and pulmonary acini of the lungs. With the tissue sampling strategies used in this study, for the first time microdosimetric relations between ozone concentrations and biological changes in precisely delineated regions of the lungs can be defined along the entire lower respiratory tract.
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PMID:Consequences of prolonged inhalation of ozone on F344/N rats: collaborative studies. Part IX: Changes in the tracheobronchial epithelium, pulmonary acinus, and lung antioxidant enzyme activity. 761 34

Male weanling rats were fed diets containing either adequate (6.2 mg/kg) or deficient (0.82 mg/kg) quantities of copper for 35 days. Six rats from each group (n = 12) were then injected with streptozotocin to induce diabetes. Rats were killed after a further 16 days and tissues removed for the analysis of the copper level and antioxidant enzyme activities. Diabetes resulted in increased cardiac catalase, glutathione S-transferase (GST), copper-zinc superoxide dismutase and manganese superoxide dismutase activities. Renal catalase levels were decreased in diabetes, while glucose-6-phosphate dehydrogenase activity (G6PDH) was increased. Diabetes significantly decreased the activities of hepatic GST and G6PDH. The combination of diabetes and copper deficiency resulted in increased levels of hepatic GST, glutathione peroxidase and glutathione reductase. Hepatic and renal tissue copper levels were also increased in diabetes, apparently improving copper status in the copper-deficient rats. Alterations of antioxidant enzyme activities in diabetes were suggestive of increased oxidant stress, especially in cardiac tissue.
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PMID:Effects of copper deficiency and experimental diabetes on tissue antioxidant enzyme levels in rats. 771 Feb 61

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


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