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)

Relative cell survival and activity of the free radical scavenging enzymes superoxide dismutase, catalase, and glutathione peroxidase were measured in cloned normal (MEA) and SV40-transformed (SVMEA) mouse embryo cells exposed at 44 degrees C for 0-3 h. At 37 degrees C, all three enzymes were 2-5 times higher in MEA than in SVMEA. Hyperthermia did not significantly alter enzyme levels in either cell line but selectively reduced transformed cell survival to less than 5% while relative survival of normal cells remained above 75%. The latter, however, could be reduced to 25% when normal cells were pretreated with 3 mM diethyldithiocarbamate, an inhibitor of copper- and zinc-containing superoxide dismutase. Similar treatment rendered SVMEA extremely thermosensitive. On the other hand, sublethal heat treatment (15 min at 45 degrees C) of cultured cells resulted in a relative thermal resistance upon subsequent exposure to 45 degrees C for 1-4 h. This induced thermotolerance was associated with a rise in antioxidant enzyme levels and both became significant only 4-6 h after the initial heat treatment. Induced enzyme and thermotolerance levels in transformed cells remained, nonetheless, far below those of normal cells. The data show that inherent (in MEA) as well as induced (in SVMEA) thermotolerance is associated with high antioxidant enzyme levels while the reverse is true in the case of inherent (in SVMEA) and induced (in MEA) thermosensitivity. These findings suggest that increased production of oxygen free radicals may be involved in hyperthermic cell injury, which then becomes a function of basal or inducible levels of antioxidant enzymes. Induction of the latter by hyperthermia is apparently inefficient in transformed cells making them more vulnerable. Enzyme induction seems also to require a lag period of 4-6 h suggesting the possible involvement of an intermediate inducer(s) at molecular level. The so-called heat shock proteins may be candidates for such a role.
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PMID:Antioxidant enzymes and survival of normal and simian virus 40-transformed mouse embryo cells after hyperthermia. 303 17

Serum levels of the trace metals copper, zinc, and selenium were measured in premature infants. White blood cell glutathione peroxidase and superoxide dismutase levels were measured in conjunction with the trace metals. Three groups of infants were evaluated: group I was relatively healthy, group II were infants with stage 2 bronchopulmonary dysplasia (BPD) or less, group III were infants with stage 3 BPD or worse. Zinc and selenium levels declined in all groups during conventional parenteral nutrition (TPN) regimens, while copper remained stable. Copper did decline in groups I and II coincident with an acceleration in growth rate. An expected rise in antioxidant enzyme levels in infants with pulmonary oxygen toxicity was not seen. This study suggests that supplemental selenium as well as an increased zinc intake over current recommendations for premature infants receiving TPN may be indicated.
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PMID:Relationship of antioxidant enzymes to trace metals in premature infants. 310 37

Exploratory factor analysis of reported specific activities of the antioxidant enzymes superoxide dismutase, catalase and glutathione peroxidase in normal human tissues, normal mouse tissues, vertebrate red blood cells and neoplastic human cell lines shows that the activities of copper-zinc superoxide dismutase, catalase and glutathione peroxidase in normal tissues are influenced by a single factor. Catalase activity has the highest loading and correlation with this factor, suggesting a catalase- or hydrogen peroxide-related influence. The activity of manganese superoxide dismutase is influenced by a separate factor. The activities of copper-zinc and manganese superoxide dismutases in normal tissues therefore appear to be dichotomously regulated. The activities of superoxide dismutase and glutathione peroxidase in vertebrate red blood cells are influenced by a single factor. The activity of catalase is influenced by a separate factor. The roles of glutathione peroxidase and catalase in hydrogen peroxide catabolism in red blood cells in fact differ. In neoplastic human cell lines, two bipolar factor factors appear to influence the activities of catalase and manganese superoxide dismutase, and glutathione peroxidase and copper-zinc superoxide dismutase, respectively. The factors are, however, mainly catalase and glutathione peroxidase activity factors as the loadings and correlations of manganese superoxide dismutase on the one hand and copper-zinc superoxide dismutase on the other, with the respective factors, are relatively small. Potentially low superoxide production and intrinsically low peroxidizability of tumour cell membranes underlie the peculiar variation of antioxidant enzyme activities in tumour cells. Factor analysis is proposed as a heuristic data reduction and hypothesis-creating technique for the variation of antioxidant and other functionally-linked enzyme activities in normal and pathological cells and tissues.
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PMID:Factor analysis of the activities of superoxide dismutase, catalase and glutathione peroxidase in normal tissues and neoplastic cell lines. 350 91

Neonatal, adult, and fetal rat lungs of 18, 20, and 22 d gestation from four to six litters were examined for cytochrome oxidase, glucose-6-phosphate dehydrogenase, catalase, glutathione peroxidase, copper-zinc and manganese superoxide dismutase activities. All results were corrected for the contribution of enzymes in blood that contaminate homogenates. Because lung protein/DNA ratios and body water change significantly with gestational age, enzyme activities were expressed as U/mg DNA. All activities were low in d 18 lung and increased with advancing gestational age. Only catalase and copper-zinc superoxide dismutase increased activity in response to air breathing, suggesting that maturation of the antioxidant enzyme system is virtually complete before delivery. Activities of glucose-6-phosphate dehydrogenase, catalase, glutathione peroxidase, and manganese superoxide dismutase were higher in neonatal than in adult lung.
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PMID:Pulmonary antioxidant enzyme maturation in the fetal and neonatal rat. I. Developmental profiles. 608 81

Differentiation-arrested monolayer lung cell cultures were developed from day 18, 20, and 22 rat fetuses and 3-day-old neonatal rats. These cultures were examined for antioxidant enzyme activity, and the values obtained were compared with previously reported in vivo activity. All cultures were catalase deficient, and activity could be restored by the addition of 0.25 microM Fe(NO3)3 X 9H2O to the culture medium. The other measured antioxidant enzymes--copper-zinc and manganese superoxide dismutase, glutathione peroxidase, and glucose 6-phosphate dehydrogenase-demonstrate gestation-dependent increases of activity in vivo that were not evident in vitro, supporting the concept of a circulating "maturation factor" during fetal life. When cultures from fetal days 20 and 22 and from neonatal day 3 lungs were challenged with 50% oxygen in the presence of serum, antioxidant enzyme activities were unchanged, and there was no evidence of cell damage as assessed by release of lactate dehydrogenase. In the absence of serum, however, fetal day 20 (but not fetal day 22 or neonatal day 3) lung cells showed evidence of cell damage and increased antioxidant enzyme activities. It is concluded that cultured immature fetal cells are more susceptible to oxygen toxicity than those derived from mature fetal or neonatal animals. This increased susceptibility cannot be explained on the basis of the reduced antioxidant enzyme activity observed in vivo.
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PMID:Differentiation-arrested rat fetal lung in primary monolayer cell culture. III. Antioxidant enzyme activity. 674 12

Studies have implicated active oxygen species (AOS) in the pathogenesis of various lung diseases. Many chemical and physical agents in the environment are potent generators of AOS, including ozone, hyperoxia, mineral dusts, paraquat, etc. These agents produce AOS by different mechanisms, but frequently the lung is the primary target of toxicity, and exposure results in damage to lung tissue to varying degrees. The lung has developed defenses to AOS-mediated damage, which include antioxidant enzymes, the superoxide dismutases [copper-zinc (CuZnSOD) and manganese-containing (MnSOD)], catalase, and glutathione peroxidase (GPX). In this review, antioxidant defenses to environmental stresses in the lung as well as in isolated pulmonary cells following exposure to a number of different oxidants, are summarized. Each oxidant appears to induce a different pattern of antioxidant enzyme response in the lung, although some common trends, i.e., induction of MnSOD following oxidants inducing inflammation or pulmonary fibrosis, in responses to oxidants occur. Responses may vary between the different cell types in the lung as a function of cell-cycle or other factors. Increases in MnSOD mRNA or immunoreactive protein in response to certain oxidants may serve as a biomarker of AOS-mediated damage in the lung.
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PMID:Regulation of antioxidant enzymes in lung after oxidant injury. 752 4

Oxidative damage due to free radical production is increased in uraemic patients and has been suggested as a possible factor contributing to the anaemia of chronic renal failure (CRF) and the pathogenesis of atherosclerosis. Oxidative stress was assessed in 40 patients with CRF maintained by either haemodialysis (HD) or continuous ambulatory peritoneal dialysis (CAPD) and in 18 healthy controls. Lipid peroxidation (assessed as malondialdehyde, MDA), total glutathione (TG), antioxidant enzyme (glutathione reductase (GSHRx), glutathione peroxidase (GSHPx) and superoxide dismutase (SOD)) activity and antioxidant associated trace metal (selenium, copper, zinc) levels were studied. Erythrocyte membrane fluidity was examined using the fluorescent probe 1,6 diphenyl-1,3,5-hexatriene (DPH). The results indicate increased levels of oxidative stress and altered erythrocyte membrane fluidity in patients treated with CAPD compared with controls and patients treated with HD. Only minor changes were observed in patients treated with HD. Altered free radical activity, oxidative stress and altered erythrocyte membrane fluidity observed in patients with CRF may contribute to the increase in vascular disease in such patients and to the anaemia of CRF.
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PMID:Oxidative stress and erythrocyte membrane fluidity in patients undergoing regular dialysis. 755 72

Manganese superoxide dismutase (MnSOD) levels were monitored as a function of time in culture to determine whether these levels were altered at logarithmic growth versus when the cells exhibited density limitation of growth. For comparison, activities of the antioxidant enzymes copper, zinc superoxide dismutase (CuZnSOD), catalase, and glutathione peroxidase were also evaluated. Four cell lines were studied, two of which exhibited density limitation of growth and two of which did not. Each cell line showed a unique antioxidant enzyme profile. The two cell lines that showed density limitation of growth also demonstrated induction of MnSOD at the time when the cells stopped proliferating in culture, whereas the other two cell lines did not show induction of MnSOD. There was no strict correlation between density limitation of growth and activities of the other antioxidant enzymes. To determine whether SOD varied with various phases of the cell cycle, NIH/3T3 cells were synchronized using serum starvation, and then SOD activities were measured during quiescence (G0) and the phase of DNA synthesis (S-phase). MnSOD was decreased during S-phase compared with G0, whereas CuZnSOD was increased during S-phase compared with G0, demonstrating alteration of SOD activities with varying phases of the cell cycle. This study suggests the possibility that increased MnSOD may correlate with decreased cell proliferation and suggests significant alterations in SOD activities during the cell cycle.
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PMID:Antioxidant enzyme levels as a function of growth state in cell culture. 763 59

Because reactive oxygen species have been implicated in the pathogenesis of various hyperproliferative and inflammatory diseases, the mRNA expression of the antioxidant enzyme superoxide dismutase was studied in psoriatic skin tissue. By using reverse transcription-PCR we found similar expression of copper, zinc superoxide dismutase (CuZnSOD) in the involved vs. uninvolved psoriatic skin. In contrast, the level of the manganese superoxide dismutase (MnSOD) mRNA message was consistently higher in lesional psoriatic skin as compared to adjacent uninvolved skin and healthy control skin. Parallel investigation of those cytokines that are thought to be direct or indirect inducers of the MnSOD activity revealed an increased mRNA expression of IL-1 beta, TNF-alpha, and GM-CSF in lesional psoriatic skin. To study if these cytokines exert a direct effect on dismutase expression in epidermal cells, human keratinocytes in culture were challenged with IL-1 beta, TNF-alpha, and GM-CSF. It was found that IL-1 beta and TNF-alpha, but not GM-CSF, induced the mRNA expression of MnSOD, and an additive effect was demonstrated for the two former cytokines. Further, the expression of both CuZnSOD and MnSOD transcripts was similar in cultured keratinocytes maintained at low differentiation (low Ca2+ medium) and cells forced to terminal differentiation (by high Ca2+ medium). Our results indicate that the abnormal expression of MnSOD mRNA in lesional psoriatic skin is not directly linked to the pathologic state of keratinocyte differentiation in the skin. It seems more likely that the cutaneous overexpression of MnSOD in psoriatic epidermis represents a protective cellular response evoked by cytokines released from inflammatory cells invading the diseased skin.
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PMID:Increased mRNA expression of manganese superoxide dismutase in psoriasis skin lesions and in cultured human keratinocytes exposed to IL-1 beta and TNF-alpha. 774 20

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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