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)

Alterations in the proteome of Arabidopsis thaliana leaves during early responses to challenge by Pseudomonas syringae pv. tomato DC3000 (DC3000) were analysed using two-dimensional (2D) gel electrophoresis. Protein changes characteristic of the establishment of basal resistance and R-gene mediated resistance were examined by comparing responses to DC3000, a hrp mutant and DC3000 expressing avrRpm1 respectively. The abundance of selected transcripts was also analysed in GeneChip experiments. Here we present data from the soluble fraction of leaf protein, highlighting changes in two antioxidant enzyme groups; the glutathione S-transferases (GSTs F2, F6, F7 and F8) and peroxiredoxins (PrxA, B and IIE). Members of both enzyme groups showed signs of specific post-translational modifications, represented by multiple spots on gels. We suggest that oxidation of specific residues is responsible for some of the spot shifts. All forms of the GST proteins identified here increased following inoculation with bacteria. GSTF8 showed particularly dynamic responses to pathogen challenge, the corresponding transcript was significantly up-regulated by 2 h after inoculation, and the protein showed post-translational modifications specific to an incompatible interaction. Differential changes were observed with the peroxiredoxin proteins; PrxIIE and to a lesser extent PrxB, no change was observed with PrxA, but a truncated form PrxA-L was greatly reduced in abundance following bacterial challenges. Our data suggest that bacterial challenge generally induces Prxs and the antioxidants GSTs, however individual members of these families may be specifically modified dependent upon the virulence of the DC3000 strain and outcome of the interaction. Finally, proteomic and transcriptomic data derived from the same inoculation system are compared and the advantages offered by 2D gel analysis discussed in light of our results.
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PMID:Specific changes in the Arabidopsis proteome in response to bacterial challenge: differentiating basal and R-gene mediated resistance. 1527 39

The activity of cytosolic antioxidative defence enzymes in the liver and white muscle of thinlip gray mullet (Liza ramada Risso) were compared in winter and spring in the Adriatic Sea. Activity of antioxidative enzymes is functionally organized due to metabolic demands: analyses of variance and correlation analysis revealed tissue- and seasonal- specific organization of antioxidative enzymes. In winter GST activity increased in both tissues compared with spring. At the same time decreased GSH-Px and GR activities were observed and this effect was more pronounced in liver then in white muscle. From correlation analyses it is concluded that the antioxidative components correlate, but the composition of the antioxidative defence system is different in respect to season and tissue. This means that the antioxidative defence system reorganizes its structure due to oxidative demands and to protect the tissues against reactive oxygen species and to establish homeostasis. Discriminant analyses separated groups according to the complete organization of individual components of the system very well and identified individual components (CAT, GST and GR) which contribute most to the differences. Statistical differences were observed between enzyme activities in tissues (liver and muscle) in both winter and spring, and between seasons (winter and spring) for liver tissue only. Since environmental parameters, such as temperature and oxygen concentration in the sea differ with season, we conclude that in this species the tissues examined expressed their antioxidative defence systems in different ways in respect of external/environmental conditions. We propose that tissue- and seasonal- specific levels of antioxidant enzyme activities should be considered in the interpretation of data from future biomonitoring field studies, especially in relation to low temperature.
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PMID:Seasonal variations of cytosolic antioxidant enzyme activities in the liver and white muscle of thinlip gray mullet (Liza ramada Risso) from the Adriatic Sea. 1537 38

We investigated the effect of betaine supplementation on ethanol induced steatosis and alterations in prooxidant and antioxidant status in the liver of guinea pigs. Animals were fed with normal chow or betaine containing chow (2% w/w) for 30 days. Ethanol (3 g/kg, i.p.) was given for the last 10 days. We found that ethanol treatment caused significant increases in plasma transaminase activities, hepatic triglyceride and lipid peroxide levels. Significant decreases in glutathione (GSH), alpha-tocopherol and total ascorbic acid (AA) levels were also observed, but hepatic superoxide dismutase, glutathione peroxidase and glutathione transferase activities remained unchanged as compared with those in controls. Betaine treatment together with ethanol in guinea pigs is found to decrease hepatic triglyceride, lipid peroxide levels and serum transaminase activities and to increase GSH levels. No changes in alpha-tocopherol and total AA levels and antioxidant enzyme activities were observed with betaine treatment in alcohol treated guinea pigs. In addition, histopathological assessment of guinea pigs showed that betaine reduced the alcoholic fat accumulation in the liver. Based on these data, betaine treatment has a restoring effect on the alterations in triglyceride, lipid peroxide and GSH levels following ethanol ingestion.
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PMID:The effect of betaine treatment on triglyceride levels and oxidative stress in the liver of ethanol-treated guinea pigs. 1538 56

In the present work, we investigated in the blue mussel (Mytilus edulis) the seasonal variations in the activity of several enzymes, which participate in the cellular defence system that is involved in the adaptive response of organisms to pollution. The activity levels of glutathione S-transferase, glutathione peroxidase, glutathione reductase and three isoforms of Cu/Zn-superoxide dismutase in gills and digestive glands of this bivalve species were used as biomarkers. Adult wild mussels were collected in Le Havre harbour (north-west coast of France) from four sites with different environmental conditions. Measurements of enzymatic activities were performed on tissue homogenates except for Cu/Zn-superoxide dismutase for which the activity of each isoform was detected on gel after isoelectric focusing. Seasonal variations in antioxidant enzyme activities were observed, characterized by low activity levels during winter, a period where oxidative stress is known to be high in bivalves. A clear-cut discrepancy between tissues was noted concerning inter-individual variability of data, which was low in gills but high in digestive gland, leading to the conclusion that gills could preferentially be used in biomonitoring studies dealing with oxidative stress in the blue mussel. As compared to animals from the reference site, mussels from the most polluted sites exhibited changes in the Cu/Zn-superoxide dismutase pattern characterized by an increase in the activity of the more acidic isoform without significant variation of the total activity of the enzyme. The most striking data were recorded in mussels collected at the outlet of a thermoelectric power plant. When compared to animals from the reference site, not only their gills showed a highly significant induction of the most acidic isoform of the Cu/Zn-superoxide dismutase (+340%, P < 0.001) but also high levels of glutathione S-transferase activity (+269%, P < 0.001). This study points out the usefulness of Cu/Zn-superoxide dismutase expression pattern as a biomarker of exposure to environmental stress rather than measurement of total activity of the enzyme, in field studies using Mytilus edulis. It also indicates the informative potential for glutathione S-transferase measurements in gills and underlines the advantages of selecting a battery of biomarkers for evaluating the impact of contamination on marine organisms.
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PMID:Seasonal variations in antioxidant defences in blue mussels Mytilus edulis collected from a polluted area: major contributions in gills of an inducible isoform of Cu/Zn-superoxide dismutase and of glutathione S-transferase. 1545 9

We investigated the effects of anoxia (8 h) and different periods of reoxygenation (20 and 40 min) on the oxidative balance in anterior and posterior gills of the crab Chasmagnathus granulata. Enzyme activity of catalase and GST was increased in the gills of the animals submitted to anoxia, and SOD activity was decreased. These enzymes returned approximately to control levels during the anoxia recovery time. These results demonstrated enzyme activities change with variations in environmental oxygen levels. The posterior gills showed a higher antioxidant enzyme activity than anterior gills. In the gills, there were no changes in the non-enzymatic antioxidant system (TRAP) during anoxia. On the other hand, during anoxia recovery, an increase of TRAP in both gills was observed. Anoxia does not change lipid peroxidation (TBARS) in the gills. During anoxia recuperation, an increase in levels of TBARS was observed. Thus the results demonstrate that C. granulata has a similar strategy of preparation for oxidative stress as observed in other intertidal species, enabling the crabs to survive in an environment with extreme variations in physical and chemical characteristics, such as salt marshes.
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PMID:Effects of environmental anoxia and different periods of reoxygenation on oxidative balance in gills of the estuarine crab Chasmagnathus granulata. 1562 9

Transgenic cotton (Gossypium hirsutum L.) lines expressing the tobacco glutathione S-transferase (GST) Nt107 were evaluated for tolerance to chilling, salinity, and herbicides, antioxidant enzyme activity, antioxidant compound levels, and lipid peroxidation. Although transgenic seedlings exhibited ten-fold and five-fold higher GST activity under normal and salt-stress conditions, respectively, germinating seedlings did not show improved tolerance to salinity, chilling conditions, or herbicides. Glutathione peroxidase (GPX) activity in transgenic seedlings was 30% to 60% higher under normal conditions, but was not different than GPX activity in wild-type seedlings under salt-stress conditions. Glutathione reductase, superoxide dismutase, ascorbate peroxidase, and monodehydroascorbate reductase activities were not increased in transgenic seedlings under salt-stress conditions, while dehydroascorbate reductase activity was decreased in transgenic seedlings under salt-stress conditions. Transgenic seedlings had 50% more oxidized glutathione when exposed to salt stress. Ascorbate levels were not increased in transgenic seedlings under salt-stress conditions. Malondialdehyde content in transgenic seedlings was nearly double that of wild-type seedlings under normal conditions and did not increase under salt-stress conditions. These results show that expression of Nt107 in cotton does not provide adequate protection against oxidative stress and suggests that the endogenous antioxidant system in cotton may be disrupted by the expression of the tobacco GST.
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PMID:Transgenic cotton (Gossypium hirsutum L.) seedlings expressing a tobacco glutathione S-transferase fail to provide improved stress tolerance. 1582 6

There is a possible role of reactive oxygen species (SROS) in the complication of implants although there is presently little information. The aim of this study was to investigate the alterations in lipid peroxidation (LP) and antioxidant enzyme activities in tissues surrounding implants in rabbits. Thirty New Zealand albino male rabbits were used. They were randomly divided into five groups. The first group (I) was used as control. Groups II, III, IV and V were implanted with stainless steel, ceramic, titanium and polyethylene, respectively. One month after the administration of implant, the tissues surrounding the implant were carefully removed for antioxidant enzyme analysis. Glucose-6-phosphate dehydrogenase (G6PD), glutathione reductase (GR), superoxide dismutases (SOD), glutathione peroxidase (GPx), catalase (CAT) in tissues surrounding the implants in the groups II, III and IV were significantly (p<0.05-p<0.001) lower than in the control group although glutathione S-transferase (GST) activities and LP values were increased. CAT activity and LP level did not decrease in group V. In conclusion, these data demonstrate that there is an increase in lipid peroxidation in the tissues surrounding ceramic and titanium implants of animals whereas there is a decrease in antioxidant enzymes. Oxidative stress plays a very important role in the complications of ceramic and titanium implants. The polyethylene implant seems to be the best of the four implant materials tested.
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PMID:Comparative study of antioxidant enzymes in tissues surrounding implant in rabbits. 1589 25

Contaminant-related changes in antioxidative processes in the freshwater crustacea Daphnia magna exposed to model redox cycling contaminant were assessed. Activities of key antioxidant enzymes including catalase, superoxide dismutase, glutathione peroxidase and glutathione S-transferases and levels of lipid peroxidation measured as thiobarbituric acid-reactive substances (TBARS) and lipofucsin pigment content were determined in D. magna juveniles after being exposed to sublethal levels of menadione, paraquat, endosulfan, cadmium and copper for 48 h. Results denoted different patterns of antioxidant enzyme responses, suggesting that different toxicants may induce different antioxidant/prooxidant responses depending on their ability to produce reactive oxygen species and antioxidant enzymes to detoxify them. Low responses of antioxidant enzyme activities for menadione and endosulfan, associated with increasing levels of lipid peroxidation and enhanced levels of antioxidant enzyme activities for paraquat, seemed to prevent lipid peroxidation, whereas high levels of both antioxidant enzyme activities and lipid peroxidation were found for copper. For cadmium, low antioxidant enzyme responses coupled with negligible increases in lipid peroxidation indicated low potential for cadmium to alter the antioxidant/prooxidant status in Daphnia. Among the studied enzymes, total glutathione peroxidase, catalase and glutathione S-transferase appeared to be the most responsive biomarkers of oxidative stress.
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PMID:Antioxidant enzyme activities and lipid peroxidation in the freshwater cladoceran Daphnia magna exposed to redox cycling compounds. 1590 63

Caddisfly larvae of Hydropsyche exocellata were sampled from seven locations receiving increasing levels of urban and industrial waste water discharges along the Llobregat river system (NE Spain) during spring and summer 2003. Locations were selected to include aquatic communities in poor and good ecological state according to measured physicochemical water parameters and the analysis of benthic macroinvertebtrate communities. Whole body residues of selected metals (Fe, Al, Zn, Cu, Co, Ni, Pb, Cd) were determined in conjunction with antioxidant enzyme activities (superoxide dismutase, SOD; catalase, CAT; glutathione peroxidase activity of GST, GSTPX), a phase II enzyme (glutathione-S-transferase, GST) and lipid peroxide levels measured as thiobarbituric reactive species (TBARs) with the aim of investigating whether resident macroinvertebrate benthic species were responsive to changes in water quality. Caddisfly larvae inhabiting those rivers were exposed to increasing levels of metal pollution. Enhanced activities of two (CAT and GST) out of the four tested enzymes, coupled with increased levels of TBARs, indicated increasing levels of stress in the studied species towards downstream reaches or locations near industrial and urban areas. These results indicate that combination of chemical and biochemical responses can be used to assess and diagnose pollution in high stressed river ecosystems.
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PMID:Trace metal concentration, antioxidant enzyme activities and susceptibility to oxidative stress in the tricoptera larvae Hydropsyche exocellata from the Llobregat river basin (NE Spain). 1591 18

Selenium-containing glutathione transferase (seleno-GST) was generated by biologically incorporating selenocysteine into the active site of glutathione transferase (GST) from a blowfly Lucilia cuprina (Diptera: Calliphoridae). Seleno-GST mimicked the antioxidant enzyme glutathione peroxidase (GPx) and catalyzed the reduction of structurally different hydroperoxides by glutathione. Kinetic investigations reveal a ping-pong kinetic mechanism in analogy with that of the natural GPx cycle as opposed to the sequential one of the wild type GST. This difference of the mechanisms might result from the intrinsic chemical properties of the incorporated residue selenocysteine, and the selenium-dependent mechanism is suggested to contribute to enhancement of the enzymatic efficiency.
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PMID:Kinetic studies on the glutathione peroxidase activity of selenium-containing glutathione transferase. 1594 61


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