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)

Air-breathing organisms experience an elevated concentration of oxygen mainly under two conditions. One occurs at birth when the O2 tension in the lung increases from approximately 25 torr present in utero to approximately 100 torr. The lungs, in particular, are also exposed to hyperoxia when oxygen is administered for therapeutic reasons. Under hyperoxic conditions, increased lung antioxidant enzyme activity is important for survival. The molecular basis for the increase in antioxidant enzyme gene expression under these circumstances is not well understood; in hyperoxia-exposed neonatal rats the elevation of lung catalase activity is not due to an increased rate of transcription but is associated with an increased concentration of catalase mRNA due to enhanced stability of the mRNA (Clerch, L.B., Iqbal, J., and Massaro, D. (1991) Am. J. Physiol. 260, L428-L433). We now show that neonatal rat lung protein forms specific complexes with catalase mRNA; this binding is redox-sensitive since when oxidizing agents are added binding is abolished but is restored by reducing agents. Our data also indicate lungs from hyperoxia-exposed rats have a larger proportion of catalase RNA-binding protein in oxidized form than lungs from air-breathing rats. This redox-sensitive binding of protein to catalase mRNA may be important in the control of catalase gene expression.
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PMID:Oxidation-reduction-sensitive binding of lung protein to rat catalase mRNA. 173 43

The antioxidant enzyme activities, the lipid peroxidation level, the parameters of glutathione metabolism, and the proportion of haemoglobin oxidation products were determined during the symptom-free period of childhood bronchial asthma. A decreased catalase activity and a significantly reduced glutathione instability were demonstrated as compared to the controls. The results indicate that antioxidant protection of the haemoglobin molecule in asthmatic children is considerably decreased.
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PMID:Examination of the role of oxygen free radicals in bronchial asthma in childhood. 175 97

To investigate the role of chronic oxidative stress in MPTP neurotoxicity, C57BL mice were maintained 6-8 weeks on diets deficient in nutrients essential to cellular antioxidant defenses, selenium (Se) and alpha-tocopherol (vit E), and the effects on tissue antioxidant status and MPTP toxicity were evaluated relative to controls on supplemented diets. Activities of the major antioxidant enzymes, glutathione peroxidase (GPx), catalase, and superoxide dismutase, and levels of malondialdehyde as a marker for oxidative stress, were measured in brain, lung, liver and blood. Caudate depletion of dopamine and its metabolites served as a measure of MPTP neurotoxicity. For mice on the Se deficient diet, levels of the selenoenzyme GPx decreased from 50% in brain to 90% in blood. No compensatory changes in the activities of the other antioxidant enzymes were observed and addition of vit E to the diet did not alter antioxidant enzyme activities or malondialdehyde levels. In animals not treated with MPTP, the Se deficient diet significantly increased malondialdehyde only in liver. No protective effect of the antioxidant supplements against caudate depletion of dopamine and its metabolites were observed. However, malondialdehyde levels were increased in the brains of MPTP treated mice on the low Se diets, suggesting the possibility of secondary oxidative damage to tissues accompanying the destruction of substantia nigra neurons by MPTP.
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PMID:Effects of low selenium diets on antioxidant status and MPTP toxicity in mice. 178 23

Oxidative injury of tissues involves both accumulation of damage due to persistent oxidative stress and loss of the proper balance of antioxidative enzymes. These events may produce a faster rate of tissue senescence. In this regard, we have assayed the antioxidative enzyme activities (Cu,Zn superoxide dismutase, glutathione peroxidase and catalase), in various areas of rat brain (prefrontal cortex, parietal cortex, hippocampus, hypothalamus, caudate nucleus, mesencephalon and lower brain stem) for the age groups of 3, 6, 12, 24 months. The results obtained show that the levels of antioxidant enzyme activities differed considerably in the various brain parts studied. Furthermore, changes in the specific activities of superoxide dismutase, catalase, and glutathione peroxidase did not follow the same pattern as a function of aging. In particular, in prefrontal cortex and caudate nucleus, superoxide dismutase and glutathione peroxidase activities did not change, while catalase activity decreased. In parietal cortex and mesencephalon, superoxide dismutase and glutathione peroxidase activities increased, but the catalase activity decreased in parietal cortex and did not change in mesencephalon. In lower brain stem, the activities of glutathione peroxidase and catalase decreased in 3-12-month-old rats. The activity of glutathione peroxidase was increased in the hippocampus and was decreased in hypothalamus during aging. In this area the catalase activity was also significantly diminished.
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PMID:Age-related changes in Cu,Zn superoxide dismutase, Se-dependent and -independent glutathione peroxidase and catalase activities in specific areas of rat brain. 179 67

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

Cold acclimation increased the activities of superoxide dismutase, catalase, total and selenium (Se)-dependent glutathione peroxidases (GPx) and glutathione reductase by 2-4-fold in the brown adipose tissue (BAT) of cold-acclimated rats. Nevertheless, when expressed per unit protein, the antioxidant enzyme activities were unaltered. Sensitivity to lipid peroxidation and GSH levels both increased by one order of magnitude in the cold on a per weight basis and were still 3-5 times greater in the cold when expressed per mg of protein. We suggest that activation of BAT leads to a large increase in the potential for lipid peroxidation and that the tissue responds to this challenge by increasing practically all of its antioxidant defences. Nevertheless, GSH, and possibly GPx activity, seem to be the principal defences involved in adaptation of the tissue to a higher sensitivity to peroxidative damage after activation.
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PMID:Effect of cold acclimation on GSH, antioxidant enzymes and lipid peroxidation in brown adipose tissue. 185 42

We hypothesized that low-dose pretreatment of an intact animal with a nontoxic derivative of endotoxin, monophosphoryl lipid A (MPL), would induce protection against cardiac ischemia/reperfusion (I/R) injury. The purposes of this study were to investigate whether MPL pretreatment would induce functional protection against cardiac I/R injury, to delineate the temporal induction of protection, and to examine antioxidant enzyme induction as a mechanism of protection. Rats were administered a 5 mg/kg dose of MPL at 2 hours and 24 hours before a 25-minute, global, 37 degrees C ischemic insult followed by reperfusion (modified Langendorff). At 40 minutes of reperfusion, ventricular function was assessed (ventricular balloon; developed pressure, rate of contraction, rate of relaxation). Hearts from rats pretreated with MPL 24 hours before isolation exhibited preservation of ventricular function (p less than 0.05). After I/R, hearts from rats pretreated with MPL 24 hours before isolation had increased (p less than 0.05) catalase activity compared to saline pretreated controls and rats pretreated with MPL 2 hours before isolation. We conclude that (1) pretreatment with MPL induces functional protection against cardiac I/R injury, (2) protection (not evident at 2 hours) is maximal at 24 hours, suggesting enzyme induction, and (3) increased catalase activity correlates with the functional protection.
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PMID:Pretreatment with a nontoxic derivative of endotoxin induces functional protection against cardiac ischemia/reperfusion injury. 185 44

Antioxidant enzyme activities of cultured human foreskin fibroblasts, keratinocytes, and melanocytes from healthy black and Caucasian donors were measured and compared. Fibroblasts had more (p less than 0.05) peroxidase, catalase, glutathione peroxidase, and superoxide dismutase activity than keratinocytes. Keratinocytes had more (p less than 0.05) peroxidase, catalase, glutathione peroxidase, and superoxide dismutase activity than melanocytes. No differences in antioxidant enzyme activities were observed between the cells of any type taken from black or Caucasian people. Antioxidant enzyme activities may affect resistance to damage by oxidants induced by ultraviolet radiation and inflammation.
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PMID:Disparate antioxidant enzyme activities in cultured human cutaneous fibroblasts, keratinocytes, and melanocytes. 187 41

The effects of aging on myocardial antioxidant enzyme activity, lipid peroxidation, and other related biochemical properties were investigated in male Wistar-Furth rats at 4, 26, and 31 mo of age at rest and after an acute exercise bout. The results showed that resting heart cytosolic superoxide dismutase (CuZn SOD) activity was significantly decreased in the heart with aging (66 +/- 6.5 U/mg protein at 4 mo vs. 49 +/- 3.8 U/mg protein at 31 mo) and was elevated in all age groups after exercise. Mitochondrial Mn SOD activity was almost doubled in both 26- and 31-mo-old rats compared with that at 4 mo. Myocardial catalase and cytosolic glutathione peroxidase (GPX) activities were significantly decreased with age, whereas mitochondrial GPX was 29% higher (P less than 0.05) in 31- than 4-mo-old rats. Glutathione S-transferase activity in the heart also declined with age (P less than 0.05 at 31 mo). Malondialdehyde contents in both heart homogenate and mitochondria were significantly increased at old age. Activity of several enzymes related to myocardial energy production, e.g., citrate synthase, malate dehydrogenase, and lactate dehydrogenase, as well as myocardial protein content showed an age-related decline. These data indicate that myocardial antioxidant capacity is weakened during aging and that the compensatory increases of mitochondrial SOD and GPX may be an important mechanism in coping with free radical damage in senescent heart. Findings in the present investigation seem to support the free radical theory of aging.
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PMID:Myocardial aging: antioxidant enzyme systems and related biochemical properties. 187 97

We studied the biological variability of blood superoxide dismutase (SOD; EC 1.15.1.1), glutathione peroxidase (GPX; EC 1.11.1.9), and catalase (CAT; EC 1.11.1.6) in a sample of 1836 apparently health subjects, ages 4-97 years. SOD and GPX activities were assayed in plasma (P) and erythrocytes (E) by automated methods, and CAT was measured in erythrocytes by a manual technique. No statistically significant variation of these antioxidant enzyme activities according to gender was demonstrated, except for E-GPX, which was slightly but significantly higher in women than in men (P less than 0.001). Activities appear rather stable in adults less than 65 years old, but decrease for most enzymes in the elderly. There is no evidence that weight, blood pressure, or menopause influences the antioxidant enzymes' activities. In girls ages 10-14 years, E-SOD activity is reduced by 16% (P less than 0.05) after menarche. Variations related to smoking and alcohol consumption are slight and concern only P-SOD and P-GPX, respectively. Conversely, intake of some drugs (e.g., anti-inflammatory agents, antidepressants, and thyroid hormones) modifies activity of some of the three enzymes. E-SOD positively correlates with P-SOD (r = 0.216, P less than 0.001) and E-CAT (r = 0.123, P less than 0.001), and E-GPX with P-GPX (r = 0.218, P less than 0.001). Finally, we propose reference intervals for activities of the three antioxidant enzymes in blood in individuals less than 65 years old.
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PMID:Biological variability of superoxide dismutase, glutathione peroxidase, and catalase in blood. 193 68


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