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)

Fetal rat lung fibroblasts were cultured in a gas phase of 20% O2, 5% CO2 (PO2 measured, 150 Torr) or 2% oxygen, 5% CO2 (PO2 measured, 25 Torr) with or without 100 nM dexamethasone (Dex). Superoxide dismutase (SOD) activity per cell increased spontaneously during 4 days of incubation at both PO2, but catalase (CAT) activity tended to fall during this time and glutathione peroxidase (GPx) activity showed no consistent trend during this interval. Cells cultured at a low PO2 had a lower protein content and SOD activity compared with air controls. Dex inhibited cell proliferation and enhanced intracellular accumulation of protein at the low PO2 but prevented the increase in protein content without affecting cell multiplication at a PO2 of 150 Torr. SOD activity per cell was enhanced by Dex at a low PO2 but reduced in 20% O2, 5% CO2. An increase in CAT and GPx activity per cell resulted on exposing fibroblasts to Dex in the presence of low PO2. These results show that Dex affects the growth and antioxidant enzyme activity of fetal lung fibroblasts, and this action of Dex can be modulated by changing the ambient PO2.
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PMID:PO2-dexamethasone interactions in fibroblast growth and antioxidant enzyme activity. 356 58

Total glutathione levels and the activity of enzymes associated with antioxidant protection in neonatal lung are increased in response to hyperoxia. Glutathione levels in developing rat lung decreased from 24 nmol/mg protein on day 19 of gestation to approximately 12 nmol/mg protein at birth. The initial decrease in glutathione may be due to emergence of other antioxidant systems. Newborn rats placed in 100% oxygen showed a rapid and sustained increase in total glutathione levels which was primarily due to an increase in reduced glutathione. Explants obtained from 16-wk gestation human fetal lung or from 17- to 18-day fetal rat lung also showed increased total and reduced glutathione when cultured in 95% oxygen, 5% CO2 as compared with explants cultured in room air. Type II cells isolated from neonatal rats maintained in oxygen for 6 days also showed glutathione levels twice those found in cells isolated from animals in room air. The activity of antioxidant enzymes (glucose-6-phosphate dehydrogenase, glutathione peroxidase, glutathione reductase) was increased in lungs of newborn rats exposed to 100% oxygen either at birth or 2 days of age. Antioxidant enzyme activity of lung explants cultured in 95% oxygen, 5% CO2 was also higher than in explants maintained in room air. These results suggest that the increases in glutathione and of antioxidant enzymes in vivo and in vitro are a direct effect of oxygen exposure in lung and that the increase of both glutathione and antioxidant enzyme activity is intrinsic to the lung cell itself. It is likely that increases in glutathione in lung represent an important protective mechanism against oxidant injury.
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PMID:The responses of glutathione and antioxidant enzymes to hyperoxia in developing lung. 403 84

The effect of a 6-kDa thymic peptide (TP) on the oxidative burst of the murine macrophage cell line J774 was determined. TP was incubated with J774 cells at 37 degrees C and 5% CO2 for 18 h, oxidative burst was triggered by zymosan, and chemiluminescence was amplified by luminol and measured in an automated luminometer. TP exhibited a concentration-dependent suppression of oxidative burst. To study the mechanisms involved in TP's suppression of oxidative burst, its effect on the glutathione redox cycle and antioxidant enzymes was investigated. J774 cells were incubated with varying concentrations of TP for 18 h, washed, resuspended in phosphate-buffered saline, and sonicated to obtain cell lysate. Biochemical assays were performed with the lysate. TP was shown to increase the level of glutathione, and activities of glutathione-peroxidase and glutathione-reductase, indicating its ability to modulate the glutathione redox cycle. The activity of antioxidant enzyme superoxide dismutase was enhanced significantly by TP treatment while catalase activity remained unaffected. These results suggest that TP possesses an antioxidant property and therefore may be involved in the regulation of free radical mediated reactions.
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PMID:Thymic peptide modulates glutathione redox cycle and antioxidant enzymes in macrophages. 814 20

It has been suggested that oxidative processes are involved in a variety of pathological conditions, notably ischemia-reperfusion injury. Moreover, anesthetics appear to exert differential effects on the severity of such injury, these being unlikely wholly attributable to their differential effects on cardiovascular or microcirculatory status. It is possible that these variable effects of anesthetics on this type of injury may be due, at least in part, to changes in the production of free radicals and/or in their detoxification by endogenous antioxidant enzymes. We have attempted to explore the latter possibility by measuring activities of catalase, superoxide dismutase (SOD), glutathione peroxidase (GPX) and glutathione reductase in normal heart tissue and red cells obtained from rats anesthetized using a variety of agents (CO2, halothane, pentobarbital or ether). For comparison, analyses were also performed on tissues from unanesthetized animals rendered unconscious by stunning prior to sacrifice. Results indicated that myocardial SOD activity was significantly greater in halothane-anesthetized as compared with CO2-anesthetized animals. Red cell SOD activities did not show such differences. However, red cell GPX activity was found to be greater in halothane-anesthetized than in pentobarbital-anesthetized rats. In general, however, antioxidant enzyme activities measured ex vivo were minimally affected by the use of anesthetics prior to euthanasia. Our findings, therefore, do not support the proposal that the influence of anesthetics on the course of ischemia-reperfusion injury involves effects at the level of enzymatic antioxidant components.
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PMID:Effects of various anesthetic regimens on tissue antioxidant enzyme activities. 816 73

Epidermal growth factor (EGF) has been shown to accelerate fetal lung maturation in rabbits, lambs, and rhesus monkeys in vivo and increase surfactant synthesis in vitro. Its effect on the maturation of the lung antioxidant enzyme system, however, is unknown. We studied the effect of EGF (10 nM) on 19-d fetal rat lung explant cultures in serum-free medium in air/5% CO2 or > 90% O2/5% CO2 compared with similarly grown control cultures in air or hyperoxia at 72 h. Fetal lung activities of superoxide dismutase and catalase were unchanged by EGF in air, whereas glutathione peroxidase activity was significantly decreased (p < 0.05 versus air control). However, in hyperoxia, EGF-treated fetal lung cultures had significantly elevated superoxide dismutase and catalase activities (p < 0.01) versus O2-exposed controls, and glutathione peroxidase activity similar to that of controls. The mRNA levels for all the antioxidant enzymes showed patterns similar to the enzyme activities except in the case of Cu,Zn-superoxide dismutase mRNA, which increased in EGF-air cultures. EGF decreased the rate of 3H-choline incorporation into disaturated phosphatidylcholine in air (p < 0.01 versus air control), but increased disaturated phosphatidylcholine synthesis in response to hyperoxia (p < 0.01 versus O2 control). The histologic appearance of EGF-treated cultures in O2 was superior to that of O2-exposed controls, which showed thickened septal walls, decreased surfactant in the air spaces, and epithelial cell mitochondrial swelling. EGF therefore accelerates antioxidant enzyme and disaturated phosphatidylcholine maturation under hyperoxic conditions and protects fetal rat lung cultures from hyperoxic injury.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Epidermal growth factor increases antioxidant enzyme and surfactant system development during hyperoxia and protects fetal rat lungs in vitro from hyperoxic toxicity. 828 92

Effects of the simulated acid rain (AR) and ultraviolet-B (UV-B, 280-320 nm) radiation with a single or two ways simultaneously (AR + UV-B) on the antioxidant enzyme and photosynthesis of the rape seedlings were investigated by the hydroponic culture. The results of static experiment indicated that the tolerance of rape seedling to single stress (AR or UV-B) is stronger than that to dual stresses (AR + UV-B). Furthermore, the dual stresses had additive effect on catalase activity, and a synergistic effect on MDA content, net photosynthesis rate, water use efficiency as well as intercellular CO2 concentration. Meanwhile, it has an independent effect on chlorophyll content, stomatal conductance, and transpiration rate as well as membrane permeability. During 64 h restoration course, the dynamic change in the curves of physiological and biochemical indices were not identical, and none of them show a simple linear variation. According to the static and dynamic experiments, it was found that a responsive sequence of catalase activity, membrane permeability, MDA content and photosynthetic characteristics to the above-mentioned stresses was as follows: AR + UV-B > UV-B > AR.
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PMID:Responses of antioxidant enzyme and photosynthesis in rape seedling to the combined stresses of acid rain and ultraviolet-B radiation. 1646 4

This paper studied the effects of short- and long term abscisic acid (ABA) treatments on the CO2 assimilation (Pn), carboxylation efficiency (CE), response of Pn to CO2, and antioxidant enzyme activities of wheat seedlings exposed to UV-C. The results showed that under no UV-C, short- and long term ABA treatments increased Pn by 14.69% and 20.46%, and decreased stomatal conductance (Gs) by 14.74% and 17.31%, respectively, compared to the control, while no effects were observed on intercellular CO2 concentration (Ci) and CE. Under UV-C, the Pn, CE, Gs and Ci decreased, with the least decrease in long term ABA treatment, less in short term ABA treatment, and the most in control. ABA could increase the response of Pn to CO2, while UV-C inhibited it. In ABA treatments, antioxidant enzyme activities were enhanced, while MDA content was decreased. Under UV-C, CAT activity increased first, reached its maximum after 1 h, and decreased then. The activities of SOD and POD in ABA treatments increased first and decreased then, with the greater increase in long term ABA treatment than in short term ABA treatment, while those in the control decreased. It was suggested that through enhancing Pn and antioxidant enzyme activities, ABA could enhance the resistance of wheat to UV-C, and long term ABA treatment had better effects than short term ABA treatment.
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PMID:[Effects of abscisic acid on photosynthetic characteristics and antioxidant enzyme activities of wheat seedlings]. 1688 8

With wheat and pea seedlings as test materials, this paper studied the effects of UV-C radiation on their leaf photosynthetic characteristics and antioxidant enzyme activities. The results showed that enhanced UV-C radiation could markedly decrease the photosynthetic rate (Pn) , stomatal conductance (Gs), intercellular CO2 concentration (Ci), transpiration rate (Tr) and carboxylation efficiency (CE) of pea leaves, but for wheat leaves, these parameters were increased first and decreased then. Under UV-C condition, the CO2 compensation point of leaf was increased for pea, but decreased first and increased then for wheat. With the increasing duration of UV-C radiation, the antioxidant enzyme activities of both test plants increased first and decreased then, except that the POD activity of pea and SOD activity of wheat decreased gradually. All of these suggested that wheat had a stronger resistance to short-time UV-C radiation than pea, but, with the prolonged duration of UV-C radiation, the photosynthesis and antioxidant enzyme activities of wheat and pea were all decreased.
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PMID:[Photosynthetic responses of wheat and pea seedlings to enhanced UV-C radiation and their resistances]. 1755 7

A pretreatment with 20kPa CO2+20 kPa O2+60 kPa N2 for 3 days proved effective in maintaining the fruit quality and controlling decay in table grapes (Vitis vinifera cv. Cardinal) stored at 0 degrees C. In the present work, we analyzed whether total anthocyanin content, the molecular mechanism implicated in their biosynthesis and antioxidant activity is related to the beneficial effect of this gaseous treatment. We isolated partial cDNAs that codified for enzymes implicated in the anthocyanin biosynthesis such as l-phenylalanine ammonia-lyase (PAL) and chalcone synthase (CHS), and an antioxidant enzyme such as ascorbate peroxidase (APX). Low temperatures induced an accumulation of total anthocyanin content in the skin of both treated and non-treated grapes, although levels were lower in CO2-treated fruit. By contrast, antioxidant activity decreased during storage at 0 degrees C in non-treated grapes but did not change in CO2-treated grapes. The up-regulation of anthocyanin biosynthesis gene expression and VcAPX mRNA observed in non-treated grape is not enhanced in CO2-treated grapes, which presented low total decay. These results point out the ability of CO2-treated grapes to prevent the generation of reactive oxygen species rather than their inactivation by means of induction of studied defense systems.
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PMID:Anthocyanin, antioxidant activity and stress-induced gene expression in high CO2-treated table grapes stored at low temperature. 1757 May 61

The distribution type and correlative links between physiological and biochemical indices characterizing functional condition of the systems of gaseous exchange (V(O2) and V(CO2)), thermoregulation (body temperature and coefficient of thermoconductivity) and antioxidant defense have been studied in 62 young (3-5 mo.) and 58 old (23-26 mo.) male C57Bl/ 6 mice. The coefficients of variation differed significantly depending on the variable but not the age-group. Mean values of V(O2) and V(CO2), body temperature and thermoconductivity, but not activities of the antioxidant enzymes, declined in aging. Moreover, the activities of catalase, glutathione-peroxidase and glutathionereductase, i.e. enzymes involved in regulation of hydrogen peroxide level, increased in aging. The correlations between V(O2) and V(CO2), V(O2) and body temperature or V(O2) and the liver pH, as well as between the antioxidant enzyme activities exhibited little age-changes. However, three-dimensional non-linear models revealed significant age-changes in relations between the studied variables.
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PMID:[The activity of gas metabolism, thermoregulation, and antioxidant enzymes in aging C57Bl/6 mice]. 1858 90


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