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Sample records for tissue glutathione peroxidase

  1. Effect of cholesterol feeding on tissue lipid perioxidation, glutathione peroxidase activity and liver microsomal functions in rats and guinea pigs

    NARCIS (Netherlands)

    TSAI, A. C.; THIE, G. M.; Lin, C. R.

    1977-01-01

    The effect of cholesterol feeding on liver and aortic nonenzymatic lipid peroxidation and glutathione peroxidase activities, and on liver microsomal NADPH-dependent lipid peroxidation, codeine hydroxylation and cytochrome P-450 levels was examined in rats and guinea pigs. One percent cholesterol was

  2. The effects of the sulfonylurea glyburide on glutathione peroxidase, superoxide dismutase and catalase activities in the heart tissue of streptozotocin-induced diabetic rat.

    Science.gov (United States)

    Bukan, N; Sancak, B; Bilgihan, A; Kosova, F; Buğdayci, G; Altan, N

    2004-09-01

    Oxygen free radicals have been suggested to be a contributory factor in diabetes complications. The aim of this study was to examine the effects of glyburide on the antioxidant enzyme activities in the heart tissue of diabetic rats. We investigated the activities of antioxidant enzymes (superoxide dismutase, catalase and glutathione peroxidase) in the hearts of both control and streptozotocin-induced diabetic rats. In the heart of diabetic rats, the activity of total superoxide dismutase decreased significantly (p < 0.005), whereas the activity of catalase and glutathione peroxidase increased to a large extent (p < 0.0001 and p = 0.05, respectively) at the end of the fourth week compared with the control group. Glyburide treatment of diabetic rats for 4 weeks corrected the changes observed in diabetic heart. In addition, blood glucose levels of untreated diabetic rats decreased following the glyburide treatment. These results demonstrate that the sulfonylurea glyburide is capable of exerting direct insulin-like effect on heart superoxide dismutase, catalase and glutathione peroxidase activities of diabetic rats in vivo.

  3. Effect of Vitamin C on Glutathione Peroxidase Activities in Pregnant ...

    African Journals Online (AJOL)

    Glutathione peroxidase is one of the most important antioxidant enzymes in humans. We studied the relationship between serum glutathione peroxidase activity and vitamin C ingestion during normal pregnancy in women attending antenatal clinic in the University of Ilorin Teaching Hospital, Ilorin. Glutathione peroxidase ...

  4. Effect of Pistacia Atlantica Extract on Glutathione Peroxidase Tissue Levels and Total Oxidative Capacity of Liver and Plasma Lipid Profile of Rats

    Directory of Open Access Journals (Sweden)

    Parvin Farzanegi

    2013-11-01

    Full Text Available Background: Exercise causes increased oxygen consumption, leaving cells exposed to oxidative stress. Antioxidants may have a protective effect by inhibiting lipid peroxidation. Thus, this study aims to examine the effect of Pistacia atlantica extract on glutathione peroxidase levels and total oxidative capacity of liver and plasma lipid profile of rats. Materials and Methods: In this experimental study, 28 female rats’ weight 155.8±2.7 grams were randomly and equally divided into 4 groups of exercise-saline, control-saline, exercise-mastic, and control-mastic. The exercise groups exercised for 8 weeks (5 days per week, 60 minutes daily, 25 meters per minute, on a zero degree slope. The rats received equal volumes of mastic and saline orally for 4 weeks. Blood and tissue samples were taken 72 hours after the last exercise session. Data were analyzed using one-way variance analysis (ANOVA.Results: Consumption of Pistacia atlantica extract together with endurance exercising for 8 weeks did not significantly affect glutathione peroxidase concentration, total oxidative capacity, LDL, triglyceride, or cholesterol, but significantly reduced HDL (p=0.002.Conclusion: Results showed that antioxidant and lipid profile levels were not affected by consumption of supplements and endurance exercising. However, further studies are required to assess the long term effects of this herbal extract.

  5. Radioimmunoassays for catalase and glutathion peroxidase

    International Nuclear Information System (INIS)

    Baret, A.; Courtiere, A.; Lorry, D.; Puget, K.; Michelson, A.M.

    1982-01-01

    Specific and sensitive radioimmunoassays for human, bovine and rat catalase (CAT) and glutathion Peroxidase (GPX) are described. The obtained values are expressed as enzymatic units per μg of immunoreactive protein. They appear to closely correspond to specific activities of the purified enzymes determined by colorimetric protein-assay. Indeed, the values of the specific activities of purified human CAT is 57.9 k/mg and that of purified rat GPX is 180 units/mg. This result validates the present RIAs and the association of the two techniques allows the determination of a further parameter. In conclusion, RIAs for CAT and GPX can be applied with great specificity and sensitivity to a wide variety of human, rat and bovine medias

  6. Hepatic and erythrocytic glutathione peroxidase activity in liver diseases.

    Science.gov (United States)

    Cordero, R; Ortiz, A; Hernández, R; López, V; Gómez, M M; Mena, P

    1996-09-01

    Hepatic and erythrocytic glutathione peroxidase activity, together with malondialdehyde levels, were determined as indicators of peroxidation in 83 patients from whom liver biopsies had been taken for diagnostic purposes. On histological study, the patients were classified into groups as minimal changes (including normal liver), steatosis, alcoholic hepatitis, hepatic cirrhosis, light to moderately active chronic hepatitis, and severe chronic active hepatitis. The glutathione peroxidase activity in erythrocytes showed no significant changes in any liver disease group. In the hepatic study, an increased activity was observed in steatosis with respect to the minimal changes group, this increased activity induced by the toxic agent in the initial stages of the alcoholic hepatic disease declining as the hepatic damage progressed. There was a negative correlation between the levels of hepatic malondialdehyde and hepatic glutathione peroxidase in subjects with minimal changes. This suggested the existence of an oxidative equilibrium in this group. This equilibrium is broken in the liver disease groups as was manifest in a positive correlation between malondialdehyde and glutathione peroxidase activity.

  7. Glutathione peroxidases of the potato cyst nematode Globodera Rostochiensis

    NARCIS (Netherlands)

    Jones, J.T.; Reavy, B.; Smant, G.; Prior, A.E.

    2004-01-01

    We report the cloning and characterisation of full-length DNAs complementary to RNA (cDNAs) encoding two glutathione peroxidases (GpXs) from a plant parasitic nematode, the potato cyst nematode (PCN) Globodera rostochiensis. One protein has a functional signal peptide that targets the protein for

  8. Glutathione peroxidases of the potato cyst nematode Globodera Rostochiensis.

    Science.gov (United States)

    Jones, J T; Reavy, B; Smant, G; Prior, A E

    2004-01-07

    We report the cloning and characterisation of full-length DNAs complementary to RNA (cDNAs) encoding two glutathione peroxidases (GpXs) from a plant parasitic nematode, the potato cyst nematode (PCN) Globodera rostochiensis. One protein has a functional signal peptide that targets the protein for secretion from animal cells while the other is predicted to be intracellular. Both genes are expressed in all parasite stages tested. The mRNA encoding the intracellular GpX is present throughout the nematode second stage juvenile and is particularly abundant in metabolically active tissues including the genital primordia. The mRNA encoding the secreted GpX is restricted to the hypodermis, the outermost cellular layer of the nematode, a location from which it is likely to be secreted to the parasite surface. Biochemical studies confirmed the secreted protein as a functional GpX and showed that, like secreted GpXs of other parasitic nematodes, it does not metabolise hydrogen peroxide but has a preference for larger hydroperoxide substrates. The intracellular protein is likely to have a role in metabolism of active oxygen species derived from internal body metabolism while the secreted protein may protect the parasite from host defences. Other functional roles for this protein are discussed.

  9. Expression of Glutathione Peroxidase and Glutathione Reductase and Level of Free Radical Processes under Toxic Hepatitis in Rats

    Directory of Open Access Journals (Sweden)

    Igor Y. Iskusnykh

    2013-01-01

    Full Text Available Correlation between intensity of free radical processes estimated by biochemiluminesce parameters, content of lipoperoxidation products, and changes of glutathione peroxidase (GP, EC 1.11.1.9 and glutathione reductase (GR, EC 1.6.4.2 activities at rats liver injury, after 12, 36, 70, 96, 110, and 125 hours & tetrachloromethane administration have been investigated. The histological examination of the liver sections of rats showed that prominent hepatocytes with marked vacuolisation and inflammatory cells which were arranged around the necrotic tissue are more at 96 h after exposure to CCl4. Moreover maximum increase in GR and GP activities, 2.1 and 2.5 times, respectively, was observed at 96 h after exposure to CCl4, what coincided with the maximum of free radical oxidation processes. Using a combination of reverse transcription and real-time polymerase chain reaction, expression of the glutathione peroxidase and glutathione reductase genes (Gpx1 and Gsr was analyzed by the determination of their respective mRNAs in the rat liver tissue under toxic hepatitis conditions. The analyses of Gpx1 and Gsr expression revealed that the transcript levels increased in 2.5- and 3.0-folds, respectively. Western blot analysis revealed that the amounts of hepatic Gpx1 and Gsr proteins increased considerably after CCl4 administration. It can be proposed that the overexpression of these enzymes could be a mechanism of enhancement of hepatocytes tolerance to oxidative stress.

  10. Novel interaction of diethyldithiocarbamate with the glutathione/glutathione peroxidase system

    International Nuclear Information System (INIS)

    Kumar, K.S.; Sancho, A.M.; Weiss, J.F.

    1986-01-01

    Diethyldithiocarbamate (DDC) exhibits a variety of pharmacologic activities, including both radioprotective and sensitizing properties. Since the glutathione/glutathione peroxidase system may be a significant factor in determining radiation sensitivity, the potential mechanisms of action of DDC in relation to this system were examined in vitro. The interaction of DDC with reduced glutathione (GSH) was tested using a simple system based on the reduction of cytochrome c. When DDC (0.005 mM) was incubated with GSH (0.5 mM), the reduction of cytochrome c was eightfold greater than that expected from an additive effect of DDC and GSH. GSH could be replaced by oxidized glutathione and glutathione reductase. Cytochrome c reduced by DDC was oxidized by mitochondria. The interaction of DDC with both the hexosemonophosphate shunt pathway and the mitochondrial respiratory chain suggests the possibility of linking these two pathways through DDC. Oxidation of DDC by peroxide and reversal by GSH indicated that the drug can engage in a cyclic reaction with peroxide and GSH. This was confirmed when DDC was used in the assay system for glutathione peroxidase (GSHPx) without GSHPx. DDC at a concentration of 0.25 mM was more active than 0.01 unit of pure GSHPx in eliminating peroxide, and much more active than the other sulfhydryl compounds tested. These studies indicate that DDC can supplement GSHPx activity or substitute for it in detoxifying peroxides, and suggests a unique role in the chemical modification of radiation sensitivity

  11. The Roles of Glutathione Peroxidases during Embryo Development.

    Science.gov (United States)

    Ufer, Christoph; Wang, Chi Chiu

    2011-01-01

    Embryo development relies on the complex interplay of the basic cellular processes including proliferation, differentiation, and apoptotic cell death. Precise regulation of these events is the basis for the establishment of embryonic structures and the organ development. Beginning with fertilization of the oocyte until delivery the developing embryo encounters changing environmental conditions such as varying levels of oxygen, which can give rise to reactive oxygen species (ROS). These challenges are met by the embryo with metabolic adaptations and by an array of anti-oxidative mechanisms. ROS can be deleterious by modifying biological molecules including lipids, proteins, and nucleic acids and may induce abnormal development or even embryonic lethality. On the other hand ROS are vital players of various signaling cascades that affect the balance between cell growth, differentiation, and death. An imbalance or dysregulation of these biological processes may generate cells with abnormal growth and is therefore potentially teratogenic and tumorigenic. Thus, a precise balance between processes generating ROS and those decomposing ROS is critical for normal embryo development. One tier of the cellular protective system against ROS constitutes the family of selenium-dependent glutathione peroxidases (GPx). These enzymes reduce hydroperoxides to the corresponding alcohols at the expense of reduced glutathione. Of special interest within this protein family is the moonlighting enzyme glutathione peroxidase 4 (Gpx4). This enzyme is a scavenger of lipophilic hydroperoxides on one hand, but on the other hand can be transformed into an enzymatically inactive cellular structural component. GPx4 deficiency - in contrast to all other GPx family members - leads to abnormal embryo development and finally produces a lethal phenotype in mice. This review is aimed at summarizing the current knowledge on GPx isoforms during embryo development and tumor development with an emphasis on

  12. Erythrocytic glutathione peroxidase: Its relationship to plasma selenium in man

    International Nuclear Information System (INIS)

    Perona, G.; Cellerino, R.; Guidi, G.C.; Moschini, G.; Stievano, B.M.; Tregnaghi, C.

    1977-01-01

    Erythrocytic glutathione-peroxidase (GSH-Px) activity and plasma selenium concentrations were measured in 14 patients: 7 with iron deficiency and 7 with raised serum iron levels. The decreased enzymatic activity in iron deficiency was confirmed. Plasma selenium was significantly lower in patients with lower serum iron; furthermore there is a significant correlation between serum iron and plasma selenium concentrations. Another correlation even more significant was found between plasma selenium and enzyme activity in all the cases we studied. These data suggests that the importance of iron for GSH-Px activity may be merely due to its relationship with selenium and that plasma selenium concentration may be of critical importance for enzyme activity. (author)

  13. Computational Modeling of the Catalytic Cycle of Glutathione Peroxidase Nanomimic.

    Science.gov (United States)

    Kheirabadi, Ramesh; Izadyar, Mohammad

    2016-12-29

    To elucidate the role of a derivative of ebselen as a mimic of the antioxidant selenoenzyme glutathione peroxidase, density functional theory and solvent-assisted proton exchange (SAPE) were applied to model the reaction mechanism in a catalytic cycle. This mimic plays the role of glutathione peroxidase through a four-step catalytic cycle. The first step is described as the oxidation of 1 in the presence of hydrogen peroxide, while selenoxide is reduced by methanthiol at the second step. In the third step of the reaction, the reduction of selenenylsulfide occurs by methanthiol, and the selenenic acid is dehydrated at the final step. Based on the kinetic parameters, step 4 is the rate-determining step (RDS) of the reaction. The bond strength of the atoms involved in the RDS is discussed with the quantum theory of atoms in molecules (QTAIM). Low value of electron density, ρ(r), and positive Laplacian values are the evidence for the covalent nature of the hydrogen bonds rupture (O 30 -H 31 , O 33 -H 34 ). A change in the sign of the Laplacian, L(r), from the positive value in the reactant to a negative character at the transition state indicates the depletion of the charge density, confirming the N 5 -H 10 and O 11 -Se 1 bond breaking. The analysis of electron location function (ELF) and localized orbital locator (LOL) of the Se 1 -N 5 and Se 1 -O 11 bonds have been done by multi-WFN program. High values of ELF and LOL at the transition state regions between the Se, N, and O atoms display the bond formation. Finally, the main donor-acceptor interaction energies were analyzed using the natural bond orbital analysis for investigation of their stabilization effects on the critical bonds at the RDS.

  14. Comparison of plasma malondialdehyde, glutathione, glutathione peroxidase, hydroxyproline and selenium levels in patients with vitiligo and healthy controls

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    Ozturk I

    2008-01-01

    Full Text Available Background: The etiology and pathophysiologic mechanism of vitiligo are still unclear. The relationship between increased oxidative stress due to the accumulation of radicals and reactive oxygen species and the associated changes in blood and epidermal component of vitiliginous skin have been reported many times. We investigated the possible changes of plasma malondialdehyde, glutathione, selenium, hydroxyproline and glutathione peroxidase activity levels in patients with vitiligo in order to evaluate the relationship between oxidative stress and etiopathogenesis of vitiligo. Materials and Methods: Plasma malondialdehyde, glutathione, hydroxyproline and glutathione peroxidase activity levels were measured by spectrophotometric methods, and HPLC was used for measurement of selenium concentrations. Results: Our results showed increased malondialdehyde, hydroxyproline and glutathione peroxidase activity levels in plasma of vitiligo group ( P < 0.05. Conclusion: Support of antioxidant system via nonenzymatic antioxidant compounds and antioxidant enzymes may be useful to prevent of melanocyte degeneration which occur due to oxidative damage in vitiligo.

  15. Changes of reduced glutathion, glutathion reductase, and glutathione peroxidase after radiation in guinea pigs

    International Nuclear Information System (INIS)

    Erden, M.; Bor, N.M.

    1984-01-01

    In this series of experiments the protective action of reduced glutathion due to ionizing radiation has been studied. In the experimental group 18 guinea pigs were exposed to successive radiations of 150 rad 3 or 4 days apart. Total dose given amounted to 750 rad which is the LD50 for guinea pigs. Blood samples were taken 30 min after each exposure. The control series were sham radiated but otherwise treated identically. The cells of the removed blood samples were separated by centrifugation and were subjected to the reduced glutathion stability test. GSSGR, GPer, and LDH enzyme activities were also measured of which the latter served as a marked enzyme. It was found that LDH did not show any alteration after radiation. The reduced glutathion stability test showed a consistent but minor reduction (P greater than 0.05), in the experimental group. GSSGR enzyme activity on the other hand was reduced significantly (from 176.48 +/- 11.32 to 41.34 +/- 1.17 IU/ml of packed erythrocytes, P less than 0.001) in the same group. GPer activity showed a consistent but minor elevation during the early phase of the experimental group. It was later increased significantly beginning after 600 rad total radiation on the fourth session (P less than 0.050)

  16. Effects of topical vitamin E on corneal superoxide dismutase, glutathione peroxidase activities and polymorphonuclear leucocyte infiltration after photorefractive keratectomy.

    Science.gov (United States)

    Bilgihan, Ayse; Bilgihan, Kamil; Yis, Ozgür; Sezer, Cem; Akyol, Gülen; Hasanreisoglu, Berati

    2003-04-01

    Photorefractive keratectomy (PRK) induces free radical formation and polymorphonuclear (PMN) cell infiltration in the cornea. Vitamin E is a free radical scavenger and protects the cells from reactive oxygen species. We investigated the effects of topical vitamin E on corneal PMN cell infiltration and corneal antioxidant enzyme activities after PRK. We studied four groups, each consisting of seven eyes. Group 1 were control eyes. In group 2 the corneal epithelium was removed by a blunt spatula (epithelial scrape). In group 3, corneal photoablation (59 micro m, 5 dioptres) was performed after epithelial removal (traditional PRK). In group 4 we tested the effects of topical Vitamin E after traditional PRK. Corneal tissues were removed and studied with enzymatic analysis (measurement of corneal superoxide dismutase and glutathione peroxidase activities) and histologically. Stromal PMN leucocyte counts were significantly higher after mechanical epithelial removal and traditional PRK (p < 0.05). Corneal superoxide dismutase and glutathione peroxidase activities decreased significantly after mechanical epithelial removal and traditional PRK (p < 0.05). In group 4, treated with vitamin E, corneal superoxide dismutase activity did not differ significantly from that in the medically non-treated groups, nor did corneal PMN cell infiltration after traditional PRK. The reduction of corneal glutathione peroxidase activity after PRK was reduced significantly after topical vitamin E treatment. Topical vitamin E treatment may be useful for reducing the harmful effects of reactive oxygen radical after epithelial scraping and PRK in that it increases corneal glutathione peroxidase activity.

  17. Activation of glutathione peroxidase via Nrf1 mediates genistein's protection against oxidative endothelial cell injury

    International Nuclear Information System (INIS)

    Hernandez-Montes, Eva; Pollard, Susan E.; Vauzour, David; Jofre-Montseny, Laia; Rota, Cristina; Rimbach, Gerald; Weinberg, Peter D.; Spencer, Jeremy P.E.

    2006-01-01

    Cellular actions of isoflavones may mediate the beneficial health effects associated with high soy consumption. We have investigated protection by genistein and daidzein against oxidative stress-induced endothelial injury. Genistein but not daidzein protected endothelial cells from damage induced by oxidative stress. This protection was accompanied by decreases in intracellular glutathione levels that could be explained by the generation of glutathionyl conjugates of the oxidised genistein metabolite, 5,7,3',4'-tetrahydroxyisoflavone. Both isoflavones evoked increased protein expression of γ-glutamylcysteine synthetase-heavy subunit (γ-GCS-HS) and increased cytosolic accumulation and nuclear translocation of Nrf2. However, only genistein led to increases in the cytosolic accumulation and nuclear translocation of Nrf1 and the increased expression of and activity of glutathione peroxidase. These results suggest that genistein-induced protective effects depend primarily on the activation of glutathione peroxidase mediated by Nrf1 activation, and not on Nrf2 activation or increases in glutathione synthesis

  18. Effects of commercial selenium products on glutathione peroxidase activity and semen quality in stud boars

    Science.gov (United States)

    The aim of this study was to determine how dietary supplementation of inorganic and organic selenium affects selenium concentration and glutathione peroxidase activity in blood and sperm of sexually mature stud boars. Twenty-four boars of the Large White, Landrace, Pietrain, and Duroc breeds of opt...

  19. Glutathione peroxidase activity in the selenium-treated alga Scenedesmus quadricauda

    Czech Academy of Sciences Publication Activity Database

    Vítová, Milada; Bišová, Kateřina; Hlavová, Monika; Zachleder, Vilém; Rucki, M.; Čížková, Mária

    2011-01-01

    Roč. 102, 1-2 (2011), s. 87-94 ISSN 0166-445X R&D Projects: GA ČR GA525/09/0102 Institutional research plan: CEZ:AV0Z50200510 Keywords : Cell cycle * Enzyme activity * Glutathione peroxidase Subject RIV: EE - Microbiology, Virology Impact factor: 3.761, year: 2011

  20. Characterization of glutathione peroxidase diversity in the symbiotic sea anemone Anemonia viridis

    OpenAIRE

    Pey , Alexis; Zamoum , Thamilla; Christen , Richard; Merle , Pierre-Laurent; Furla , Paola

    2016-01-01

    International audience; Cnidarians living in symbiosis with photosynthetic dinoflagellates (commonly named zooxanthellae) are exposed to high concentrations of reactive oxygen species (ROS) upon illumination. To quench ROS production, both the cnidarian host and zooxanthellae express a full suite of antioxidant enzymes. Studying antioxidative balance is therefore crucial to understanding how symbiotic cnidarians cope with ROS production. We characterized glutathione peroxidases (GPx) in the s...

  1. Identification and characterization of a selenium-dependent glutathione peroxidase in Setaria cervi

    International Nuclear Information System (INIS)

    Singh, Anchal; Rathaur, Sushma

    2005-01-01

    Setaria cervi a bovine filarial parasite secretes selenium glutathione peroxidase during in vitro cultivation. A significant amount of enzyme activity was detected in the somatic extract of different developmental stages of the parasite. Among different stages, microfilariae showed a higher level of selenium glutathione peroxidase activity followed by males then females. However, when the activity was compared in excretory secretory products of these stages males showed higher activity than microfilariae and female worms. The enzyme was purified from female somatic extract using a combination of glutathione agarose and gel filtration chromatography, which migrated as a single band of molecular mass ∼20 kDa. Selenium content of purified enzyme was estimated by atomic absorption spectroscopy and found to be 3.5 ng selenium/μg of protein. Further, inhibition of enzyme activity by potassium cyanide suggested the presence of selenium at the active site of enzyme. This is the first report of identification of selenium glutathione peroxidase from any filarial parasite

  2. Transmutation of human glutathione transferase A2-2 with peroxidase activity into an efficient steroid isomerase.

    Science.gov (United States)

    Pettersson, Par L; Johansson, Ann-Sofie; Mannervik, Bengt

    2002-08-16

    A major goal in protein engineering is the tailor-making of enzymes for specified chemical reactions. Successful attempts have frequently been based on directed molecular evolution involving libraries of random mutants in which variants with desired properties were identified. For the engineering of enzymes with novel functions, it would be of great value if the necessary changes of the active site could be predicted and implemented. Such attempts based on the comparison of similar structures with different substrate selectivities have previously met with limited success. However, the present work shows that the knowledge-based redesign restricted to substrate-binding residues in human glutathione transferase A2-2 can introduce high steroid double-bond isomerase activity into the enzyme originally characterized by glutathione peroxidase activity. Both the catalytic center activity (k(cat)) and catalytic efficiency (k(cat)/K(m)) match the values of the naturally evolved glutathione transferase A3-3, the most active steroid isomerase known in human tissues. The substrate selectivity of the mutated glutathione transferase was changed 7000-fold by five point mutations. This example demonstrates the functional plasticity of the glutathione transferase scaffold as well as the potential of rational active-site directed mutagenesis as a complement to DNA shuffling and other stochastic methods for the redesign of proteins with novel functions.

  3. A novel plant glutathione S-transferase/peroxidase suppresses Bax lethality in yeast

    DEFF Research Database (Denmark)

    Kampranis, S C; Damianova, R; Atallah, M

    2000-01-01

    The mammalian inducer of apoptosis Bax is lethal when expressed in yeast and plant cells. To identify potential inhibitors of Bax in plants we transformed yeast cells expressing Bax with a tomato cDNA library and we selected for cells surviving after the induction of Bax. This genetic screen allows...... for the identification of plant genes, which inhibit either directly or indirectly the lethal phenotype of Bax. Using this method a number of cDNA clones were isolated, the more potent of which encodes a protein homologous to the class theta glutathione S-transferases. This Bax-inhibiting (BI) protein was expressed...... in Escherichia coli and found to possess glutathione S-transferase (GST) and weak glutathione peroxidase (GPX) activity. Expression of Bax in yeast decreases the intracellular levels of total glutathione, causes a substantial reduction of total cellular phospholipids, diminishes the mitochondrial membrane...

  4. Characterization of glutathione peroxidase diversity in the symbiotic sea anemone Anemonia viridis.

    Science.gov (United States)

    Pey, Alexis; Zamoum, Thamilla; Christen, Richard; Merle, Pierre-Laurent; Furla, Paola

    2017-01-01

    Cnidarians living in symbiosis with photosynthetic dinoflagellates (commonly named zooxanthellae) are exposed to high concentrations of reactive oxygen species (ROS) upon illumination. To quench ROS production, both the cnidarian host and zooxanthellae express a full suite of antioxidant enzymes. Studying antioxidative balance is therefore crucial to understanding how symbiotic cnidarians cope with ROS production. We characterized glutathione peroxidases (GPx) in the symbiotic cnidarian Anemonia viridis by analysis of their isoform diversity, their activity distribution in the three cellular compartments (ectoderm, endoderm and zooxanthellae) and their involvement in the response to thermal stress. We identified a GPx repertoire through a phylogenetic analysis showing 7 GPx transcripts belonging to the A. viridis host and 4 GPx transcripts strongly related to Symbiodinium sp. The biochemical approach, used for the first time with a cnidarian species, allowed the identification of GPx activity in the three cellular compartments and in the animal mitochondrial fraction, and revealed a high GPx electrophoretic diversity. The symbiotic lifestyle of zooxanthellae requires more GPx activity and diversity than that of free-living species. Heat stress induced no modification of GPx activities. We highlight a high GPx diversity in A. viridis tissues by genomic and biochemical approaches. GPx activities represent an overall constitutive enzymatic pattern inherent to symbiotic lifestyle adaptation. This work allows the characterization of the GPx family in a symbiotic cnidarian and establishes a foundation for future studies of GPx in symbiotic cnidarians. Copyright © 2016 Elsevier B.V. and Société Française de Biochimie et Biologie Moléculaire (SFBBM). All rights reserved.

  5. Effect of Nonsurgical Periodontal Therapy on Crevicular Fluid and Serum Glutathione Peroxidase Levels

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    Swati Pradeep Patel

    2012-01-01

    Full Text Available Background: Plasma glutathione peroxidase (eGPx is an important selenium containing antioxidant in human defense against oxidative stress. While crevicular fluid (GCF eGPx levels and its association with periodontal disease is well documented, there is no data on correlation of GCF and serum eGPx levels in chronic periodontitis. Hence this study was undertaken to further probe into the role of oxidative stress in periodontal diseases and effect of nonsurgical periodontal therapy (NSPT by correlating GCF and serum levels of eGPx.

  6. Tumor suppressor function of the plasma glutathione peroxidase Gpx3 in colitis-associated carcinoma

    Science.gov (United States)

    Barrett, Caitlyn W.; Ning, Wei; Chen, Xi; Smith, J. Joshua; Washington, Mary K; Hill, Kristina E.; Coburn, Lori A.; Peek, Richard M.; Chaturvedi, Rupesh; Wilson, Keith T.; Burk, Raymond F.; Williams, Christopher S.

    2012-01-01

    The glutathione peroxidases, a family of selenocysteine-containing redox enzymes, play pivotal roles in balancing the signaling, immunomodulatory and deleterious effects of reactive oxygen species (ROS). The glutathione peroxidase GPX3 is the only extracellular member of this family, suggesting it may defend cells against ROS in the extracellular environment. Notably, GPX3 hypermethylation and underexpression occurs commonly in prostate, gastric, cervical, thyroid and colon cancers. We took a reverse genetics approach to investigate whether GPX3 would augment inflammatory colonic tumorigenesis, a process characterized by oxidative stress and inflammation, comparing Gpx3−/− mice established two-stage model of inflammatory colon carcinogenesis. Gpx3-deficient mice exhibited an increased tumor number, though not size, along with a higher degree of dysplasia. Additionally, they exhibited increased inflammation with redistribution towards pro-tumorigenic M2 macrophage subsets, increased proliferation, hyperactive WNT signaling, and increased DNA damage. To determine the impact of acute gene loss in an established colon cancer line, we silenced GPX3 in human Caco2 cells, resulting in increased ROS production, DNA damage and apoptosis in response to oxidative stress, combined with decreased contact-independent growth. Taken together, our results suggested an immunomodulatory role for GPX3 that limits the development of colitis-associated carcinoma. PMID:23221387

  7. Selenium-Enriched Foods Are More Effective at Increasing Glutathione Peroxidase (GPx) Activity Compared with Selenomethionine: A Meta-Analysis

    Science.gov (United States)

    Bermingham, Emma N.; Hesketh, John E.; Sinclair, Bruce R.; Koolaard, John P.; Roy, Nicole C.

    2014-01-01

    Selenium may play a beneficial role in multi-factorial illnesses with genetic and environmental linkages via epigenetic regulation in part via glutathione peroxidase (GPx) activity. A meta-analysis was undertaken to quantify the effects of dietary selenium supplementation on the activity of overall GPx activity in different tissues and animal species and to compare the effectiveness of different forms of dietary selenium. GPx activity response was affected by both the dose and form of selenium (p selenium supplementation on GPx activity (p selenium supply include red blood cells, kidney and muscle. The meta-analysis identified that for animal species selenium-enriched foods were more effective than selenomethionine at increasing GPx activity. PMID:25268836

  8. Oxidative status, in vitro iron-induced lipid oxidation and superoxide dismutase, catalase and glutathione peroxidase activities in rhea meat.

    Science.gov (United States)

    Terevinto, A; Ramos, A; Castroman, G; Cabrera, M C; Saadoun, A

    2010-04-01

    Rhea (Rhea americana) muscles Obturatorius medialis (OM) Iliotibialis lateralis (IL) and Iliofibularis (I), obtained from farmed animals, were evaluated regarding their oxidative/antioxidant status. The mean level of thiobarbituric acid reactive substances (TBARS) expressed as malonaldehyde (MDA) content was of 0.84 mg MDA/kg wet tissue for the three muscles. TBARS level was significantly higher in IL than OM and I, with the two latter showing similar levels. The mean level of carbonyl proteins expressed as dinitrophenylhydrazine (DNPH) was 1.59 nmol DNPH mg(-1). Carbonyl protein levels were significantly different (POM>I). Iron-induced TBARS generation was not significantly different between the three muscles at any time, nor for each muscle during the 5 h of the experiment. Superoxide dismutase activity in IL muscle was significantly higher (P<0.05) than in I muscle. However, the difference between IL and OM muscles was not significant. The differences between the three muscles became not significant when the results were expressed by mg of protein contained in the extract, instead by g of wet tissue. No differences were found for catalase (micromol of discomposed H(2)O(2) min(-1) g(-1) wet tissue or by mg of protein contained in the extract) and glutathione peroxidase (micromol ol of oxidized NADPH min(-1) g(-1) of wet tissue or by mg of protein contained in the extract) activities between the three muscles. 2009 Elsevier Ltd. All rights reserved.

  9. Ablation of ferroptosis regulator glutathione peroxidase 4 in forebrain neurons promotes cognitive impairment and neurodegeneration

    Directory of Open Access Journals (Sweden)

    William Sealy Hambright

    2017-08-01

    Full Text Available Synaptic loss and neuron death are the underlying cause of neurodegenerative diseases such as Alzheimer's disease (AD; however, the modalities of cell death in those diseases remain unclear. Ferroptosis, a newly identified oxidative cell death mechanism triggered by massive lipid peroxidation, is implicated in the degeneration of neurons populations such as spinal motor neurons and midbrain neurons. Here, we investigated whether neurons in forebrain regions (cerebral cortex and hippocampus that are severely afflicted in AD patients might be vulnerable to ferroptosis. To this end, we generated Gpx4BIKO mouse, a mouse model with conditional deletion in forebrain neurons of glutathione peroxidase 4 (Gpx4, a key regulator of ferroptosis, and showed that treatment with tamoxifen led to deletion of Gpx4 primarily in forebrain neurons of adult Gpx4BIKO mice. Starting at 12 weeks after tamoxifen treatment, Gpx4BIKO mice exhibited significant deficits in spatial learning and memory function versus Control mice as determined by the Morris water maze task. Further examinations revealed that the cognitively impaired Gpx4BIKO mice exhibited hippocampal neurodegeneration. Notably, markers associated with ferroptosis, such as elevated lipid peroxidation, ERK activation and augmented neuroinflammation, were observed in Gpx4BIKO mice. We also showed that Gpx4BIKO mice fed a diet deficient in vitamin E, a lipid soluble antioxidant with anti-ferroptosis activity, had an expedited rate of hippocampal neurodegeneration and behavior dysfunction, and that treatment with a small-molecule ferroptosis inhibitor ameliorated neurodegeneration in those mice. Taken together, our results indicate that forebrain neurons are susceptible to ferroptosis, suggesting that ferroptosis may be an important neurodegenerative mechanism in diseases such as AD. Keywords: Ferroptosis, Neurodegeneration, Cognitive impairment, Alzheimer's disease, Glutathione peroxidase 4, Transgenic mice

  10. A redox-dependent dimerization switch regulates activity and tolerance for reactive oxygen species of barley seed glutathione peroxidase

    DEFF Research Database (Denmark)

    Navrot, Nicolas; Skjoldager, Nicklas; Bunkenborg, Jakob

    2015-01-01

    Monomeric and dimeric forms of recombinant barley (Hordeum vulgare subsp. vulgare) glutathione peroxidase 2 (HvGpx2) are demonstrated to display distinctly different functional properties in vitro. Monomeric HvGpx2 thus has five fold higher catalytic efficiency than the dimer towards tert-butyl h...

  11. High-Resolution Imaging of Selenium in Kidneys: A Localized Selenium Pool Associated with Glutathione Peroxidase 3

    Science.gov (United States)

    Malinouski, Mikalai; Kehr, Sebastian; Finney, Lydia; Vogt, Stefan; Carlson, Bradley A.; Seravalli, Javier; Jin, Richard; Handy, Diane E.; Park, Thomas J.; Loscalzo, Joseph; Hatfield, Dolph L.

    2012-01-01

    Abstract Aim: Recent advances in quantitative methods and sensitive imaging techniques of trace elements provide opportunities to uncover and explain their biological roles. In particular, the distribution of selenium in tissues and cells under both physiological and pathological conditions remains unknown. In this work, we applied high-resolution synchrotron X-ray fluorescence microscopy (XFM) to map selenium distribution in mouse liver and kidney. Results: Liver showed a uniform selenium distribution that was dependent on selenocysteine tRNA[Ser]Sec and dietary selenium. In contrast, kidney selenium had both uniformly distributed and highly localized components, the latter visualized as thin circular structures surrounding proximal tubules. Other parts of the kidney, such as glomeruli and distal tubules, only manifested the uniformly distributed selenium pattern that co-localized with sulfur. We found that proximal tubule selenium localized to the basement membrane. It was preserved in Selenoprotein P knockout mice, but was completely eliminated in glutathione peroxidase 3 (GPx3) knockout mice, indicating that this selenium represented GPx3. We further imaged kidneys of another model organism, the naked mole rat, which showed a diminished uniformly distributed selenium pool, but preserved the circular proximal tubule signal. Innovation: We applied XFM to image selenium in mammalian tissues and identified a highly localized pool of this trace element at the basement membrane of kidneys that was associated with GPx3. Conclusion: XFM allowed us to define and explain the tissue topography of selenium in mammalian kidneys at submicron resolution. Antioxid. Redox Signal. 16, 185–192. PMID:21854231

  12. High-resolution imaging of selenium in kidneys: a localized selenium pool associated with glutathione peroxidase 3

    Energy Technology Data Exchange (ETDEWEB)

    Malinouski, M.; Kehr, S.; Finney, L.; Vogt, S.; Carlson, B.A.; Seravalli, J.; Jin, R.; Handy, D.E.; Park, T.J.; Loscalzo, J.; Hatfield, D.L.; Gladyshev, V.N. (Harvard-Med)

    2012-04-17

    Recent advances in quantitative methods and sensitive imaging techniques of trace elements provide opportunities to uncover and explain their biological roles. In particular, the distribution of selenium in tissues and cells under both physiological and pathological conditions remains unknown. In this work, we applied high-resolution synchrotron X-ray fluorescence microscopy (XFM) to map selenium distribution in mouse liver and kidney. Liver showed a uniform selenium distribution that was dependent on selenocysteine tRNA{sup [Ser]Sec} and dietary selenium. In contrast, kidney selenium had both uniformly distributed and highly localized components, the latter visualized as thin circular structures surrounding proximal tubules. Other parts of the kidney, such as glomeruli and distal tubules, only manifested the uniformly distributed selenium pattern that co-localized with sulfur. We found that proximal tubule selenium localized to the basement membrane. It was preserved in Selenoprotein P knockout mice, but was completely eliminated in glutathione peroxidase 3 (GPx3) knockout mice, indicating that this selenium represented GPx3. We further imaged kidneys of another model organism, the naked mole rat, which showed a diminished uniformly distributed selenium pool, but preserved the circular proximal tubule signal. We applied XFM to image selenium in mammalian tissues and identified a highly localized pool of this trace element at the basement membrane of kidneys that was associated with GPx3. XFM allowed us to define and explain the tissue topography of selenium in mammalian kidneys at submicron resolution.

  13. Relationship between oxidizable fatty acid content and level of antioxidant glutathione peroxidases in marine fish

    Science.gov (United States)

    Grim, Jeffrey M.; Hyndman, Kelly A.; Kriska, Tamas; Girotti, Albert W.; Crockett, Elizabeth L.

    2011-01-01

    SUMMARY Biological membranes can be protected from lipid peroxidation by antioxidant enzymes including catalase (CAT) and selenium-dependent glutathione peroxidases 1 and 4 (GPx1 and GPx4). Unlike GPx1, GPx4 can directly detoxify lipid hydroperoxides in membranes without prior action of phospholipase A2. We hypothesized that (1) GPx4 is enhanced in species that contain elevated levels of highly oxidizable polyunsaturated fatty acids (PUFA) and (2) activities of antioxidant enzymes are prioritized to meet species-specific oxidative stresses. In this study we examined (i) activities of the oxidative enzyme citrate synthase (CS) and antioxidant (CAT, GPx1 and GPx4) enzymes, (ii) GPx4 protein expression, and (iii) phospholipid composition in livers of five species of marine fish (Myxine glutinosa, Petromyzon marinus, Squalus acanthias, Fundulus heteroclitus and Myoxocephalus octodecemspinosus) that contain a range of PUFA. GPx4 activity was, on average, 5.8 times higher in F. heteroclitus and S. acanthias than in the other three marine fish species sampled. Similarly, activities of CAT and GPx1 were highest in S. acanthias and F. heteroclitus, respectively. GPx4 activity for all species correlates with membrane unsaturation, as well as oxidative activity as indicated by CS. These data support our hypothesis that GPx4 level in marine fish is a function, at least in part, of high PUFA content in these animals. GPx1 activity was also correlated with membrane unsaturation, indicating that marine species partition resources among glutathione-dependent defenses for protection from the initial oxidative insult (e.g. H2O2) and to repair damaged lipids within biological membranes. PMID:22031739

  14. The effect of intermittent hypobaric-hypoxia treatments on renal glutathione peroxidase activity of rats

    Science.gov (United States)

    Paramita, I. A.; Jusman, S. W. A.

    2017-08-01

    Many people living at high altitudes experiencing a condition called intermittent hypobaric hypoxia (IHH). Some people even create IHH condition as an exercise for pilots, athletes, and mountaineers. In this experiment, we aimed to determine whether the protective effect of IHH is mediated through glutathione peroxidase (GPX) enzyme. The experiment’s sample is two-month-old healthy Sprague-Dawley rat kidneys weighing 200-250 g. Intermittent hypobaric hypoxia treatment is done using a Hypobaric Chamber type I that can mimic air pressure at certain altitudes: 35,000 (one minute), 30,000 (three minutes), 25,000 (five minutes), and 18,000 (30 minutes) feet. The rats were divided into five treatment groups, including a control group, hypobaric-hypoxia group, and intermittent hypobaric-hypoxia 1x, 2x, and 3x groups with each group consisting of three rats. The specific activity of GPX was measured using RANDOX and RANSEL methods. The statistical analysis of one way-ANOVA did not show significant differences between the groups (p > 0.05), although specific activities of the renal GPX of rats exposed to hypobaric-hypoxia were higher than the control group. This may be caused by the other antioxidants’ activities. In conclusion, the IHH treatment did not affect GPX activity in the rat kidneys.

  15. Cross sectional and longitudinal study on selenium, glutathione peroxidase, smoking, and occupational exposure in coal miners

    Energy Technology Data Exchange (ETDEWEB)

    Nadif, R.; Oryszczyn, M.P.; Fradier-Dusch, M.; Hellier, G.; Bertrand, J.P.; Pham, Q.T.; Kauffmann, F. [INSERM, Vandoeuvre-les-Nancy (France). Faculty of Medicine

    2001-04-01

    The aim of the study was to understand the variations of selenium (Se) concentration relative to changes in occupational exposure to coal dust, taking into account age and changes in smoking habits in miners surveyed twice, in 1990 and 1994. It was found that selenium concentration and glutathione peroxidase activities (GSH-Px) activities were significantly lower in active than in retired miners. Moreover, Se concentration was lower in miners exposed to high compared with those exposed to low dust concentrations. In miners exposed to high dust concentrations, Se concentration was significantly lower whereas erythrocyte GSH-Px activity was significantly higher in the subgroup with estimated cumulative exposure {gt} 68 mg/m{sup 3}.y. In all miners, plasma GSH-Px activity was correlated with Se concentration. The 4 year Se changes were negatively related to exposure to high dust concentrations and positively related to change in exposure from high to retirement and to change from smoker to ex-smoker. The variations of Se concentration in relation to changes in occupational exposure to coal dust and in smoking habits, and the close correlation found between plasma Se concentration and GSH-Px activity suggest that both are required in antioxidant defence. These results agree well with the hypothesis that the decrease in Se concentration reflects its use against reactive oxygen species generated by exposure to coal mine dust and by smoking.

  16. Sex determines the influence of smoking and gene polymorphism on glutathione peroxidase activity in erythrocytes

    DEFF Research Database (Denmark)

    Malling, Tine Halsen; Sigsgaard, Torben; Andersen, Helle Raun

    2009-01-01

    OBJECTIVE: Glutathione peroxidase 1 (GPX1) is one of the major oxidative enzymes. Our aim was to characterize factors influencing its activity and to determine whether or not the activity is associated with asthma. MATERIAL AND METHODS: Serum selenium concentration was measured, GPX1 polymorphisms...... %) had doctor-diagnosed asthma. RESULTS: The average serum selenium concentration was too low for optimal enzyme activity (mean (SE), 83.4 (0.76) ng/mL). GPX1 activity in men was lower than in women, 52.6 (0.66) and 56.4 (0.59) U/g protein, respectively (p... associated with serum selenium concentration (p = 0.005) and negatively associated with both active smoking (p = 0.009) and exposure to environmental tobacco smoke (p = 0.02). In women, activity was associated with genotypes with 59.2 (1.4), 56.0 (1.4) and 54.2 (1.4) U/g protein in the homozygote wild...

  17. Glutathione Peroxidase-1 Suppresses the Unfolded Protein Response upon Cigarette Smoke Exposure

    Directory of Open Access Journals (Sweden)

    Patrick Geraghty

    2016-01-01

    Full Text Available Oxidative stress provokes endoplasmic reticulum (ER stress-induced unfolded protein response (UPR in the lungs of chronic obstructive pulmonary (COPD subjects. The antioxidant, glutathione peroxidase-1 (GPx-1, counters oxidative stress induced by cigarette smoke exposure. Here, we investigate whether GPx-1 expression deters the UPR following exposure to cigarette smoke. Expression of ER stress markers was investigated in fully differentiated normal human bronchial epithelial (NHBE cells isolated from nonsmoking, smoking, and COPD donors and redifferentiated at the air liquid interface. NHBE cells from COPD donors expressed heightened ATF4, XBP1, GRP78, GRP94, EDEM1, and CHOP compared to cells from nonsmoking donors. These changes coincided with reduced GPx-1 expression. Reintroduction of GPx-1 into NHBE cells isolated from COPD donors reduced the UPR. To determine whether the loss of GPx-1 expression has a direct impact on these ER stress markers during smoke exposure, Gpx-1−/− mice were exposed to cigarette smoke for 1 year. Loss of Gpx-1 expression enhanced cigarette smoke-induced ER stress and apoptosis. Equally, induction of ER stress with tunicamycin enhanced antioxidant expression in mouse precision-cut lung slices. Smoke inhalation also exacerbated the UPR response during respiratory syncytial virus infection. Therefore, ER stress may be an antioxidant-related pathophysiological event in COPD.

  18. The effects of selenium on glutathione peroxidase activity and radioprotection in mammalian cells

    International Nuclear Information System (INIS)

    Diamond, A.M.; Murray, J.L.; Dale, P.; Tritz, R.; Grdina, D.J.

    1995-01-01

    The media of representative mammalian cell lines were supplemented with low levels of selenium in the form of sodium selenite in order to investigate the effects of selenium on mammalian cells. Following incubation in 30 nM sodium selenite, these cells were assayed for changes in glutathione peroxidase (GPx) activity. The cells examined included NIH 3T3 mouse fibroblasts, PC12 rat sympathetic precursor cells, SupT-1 human lymphocytes, MCF-7 adr human breast carcinoma cells and AA8 Chinese hamster ovary cells. Selenium supplementation resulted in a marginal increase in GPx activity for the NIH 3T3, MCF-7 adr and Supt-1 cells but stimulated GPx activity approximately 5-fold in PC12 and AA8 cells. AA8 cells were selected to evaluate whether selenium supplementation was radioprotective against 60 cobalt gamma irradiation. Protection against radiation-induced mutation was measured by evaluating mutation frequency at the hprt locus. In this assay, preincubation of AA8 CHO cells significantly protected these cells from exposure to 8 Gy

  19. The effect of excimer laser keratectomy on corneal glutathione peroxidase activities and aqueous humor selenium levels in rabbits.

    Science.gov (United States)

    Yis, Ozgür; Bilgihan, Ayşe; Bilgihan, Kamil; Yis, Nilgün Safak; Hasanreisoğlu, Berati

    2002-06-01

    The formation of free oxygen radicals has been demonstrated in the corneal tissue after 193 nm laser irradiation. Cornea has several defense mechanisms that protect against oxidative damage. One of them, glutathione peroxidase (GPx), catalyzes the destruction of hydrogen peroxide and lipid hydroperoxide. Selenium is a trace element which is incorporated into the selenoenzyme GPx. In the present study, the effect of excimer laser keratectomy on corneal GPx activities and aqueous humor selenium concentrations in rabbits was evaluated. Animals were divided into five groups, and all groups were compared: controls (group 1), after epithelial scraping (group 2), transepithelial photorefractive keratectomy(PRK; group 3), superficial traditional PRK (50 microm; group 4) and deep traditional PRK (100 microm; group 5). Corneal GPx activities were measured by a modification of the coupled assay procedure. Aqueous humor selenium concentrations were determined using hydride generation atomic absorption spectrometry. Corneal GPx activities were significantly lower only in group 5 ( P<0.05), and the selenium concentration in the aqueous humor did not change in any group. Deep corneal photoablation inhibits GPx enzyme activities in the cornea. Therefore, antioxidants may be useful in reducing free radical-mediated complications after excimer laser corneal photoablation.

  20. The effect of EGb 761 on retinal lipid peroxidation and glutathione peroxidase level in experimental lens induced uveitis.

    Science.gov (United States)

    Bilgihan, A; Aricioğlu, A; Bilgihan, K; Onol, M; Hasanreisoğlu, B; Türközkan, N

    1994-01-01

    An acute lens-induced necrotizing intraocular inflammation was produced in pigmented guinea pigs. Treatment of these animals by 100 mg/kg/day EGb 761 a free oxygen radical scavenger for 10 days, reduced retinal lipid peroxidation (p > 0.05) and increased the retinal glutathione peroxidase level (p > 0.05). Although not significantly, these findings suggest that EGb 761 could be combined with other antiinflammatory drugs and may be beneficial in the treatment of uveitis.

  1. Clinical Assessment of glutathione peroxidase and catalase to the status of malondialdehyde in urolithiasis

    International Nuclear Information System (INIS)

    Mahmoud, R.H.; Ewadh, M.J.; Al-Hamadani, K.J.

    2010-01-01

    Objective: To assess the role of lipid peroxidation and antioxidant enzymes in serum of urolithiasis patients. Methodology: Glutathione peroxidase (GPx), catalase (CAT) and malondialadehyde (MDA) in serum of urolithiasis patients have been measured. Results: The study has revealed a significant increase in MDA and a significant decrease in GPx and CAT. There have been no significant correlations of serum MDA, GPx and CAT to the size and number of stones with no differences in their levels among patients with one stone, two stones and multiple stones. Anatomically the distributions of urinary stones have been 70.14% renal, 19.30% ureteric and 3.15% urinary bladder. There have been no significant difference in serum levels of neither MDA nor CAT among all the anatomical sites of the stone, while GPx has shown a significant difference in serum of patients with renal calyceal, renal pelvic, ureteric and vesical stones. Patients with recurrent episode of urinary stone have been 63.33%. Family histories of urolithiasis have been negative in 73.33% of the patients. Neither recurrence of urinary stone nor family history of urolithiasis have shown a significant correlation with serum levels of MDA, GPx and CAT. Conclusion: The role of lipid peroxidation and antioxidant enzymes is present in the pathogenesis of urinary stone, but their levels don't affect by the size, the number and the anatomical position of stones (apart of GPx which has been affected by the anatomical position of the stone) and the duration, recurrence, and family history of the disease. (author)

  2. The effects of redox controls mediated by glutathione peroxidases on root architecture in Arabidopsis thaliana.

    Science.gov (United States)

    Passaia, Gisele; Queval, Guillaume; Bai, Juan; Margis-Pinheiro, Marcia; Foyer, Christine H

    2014-03-01

    Glutathione peroxidases (GPXs) fulfil important functions in oxidative signalling and protect against the adverse effects of excessive oxidation. However, there has been no systematic characterization of the functions of the different GPX isoforms in plants. The roles of the different members of the Arabidopsis thaliana GPX gene (AtGPX) family were therefore investigated using gpx1, gpx2, gpx3, gpx4, gpx6, gpx7, and gpx8 T-DNA insertion mutant lines. The shoot phenotypes were largely similar in all genotypes, with small differences from the wild type observed only in the gpx2, gpx3, gpx7, and gpx8 mutants. In contrast, all the mutants showed altered root phenotypes compared with the wild type. The gpx1, gpx4, gpx6, gpx7, and gpx8 mutants had a significantly greater lateral root density (LRD) than the wild type. Conversely, the gpx2 and gpx3 mutants had significantly lower LRD values than the wild type. Auxin increased the LRD in all genotypes, but the effect of auxin was significantly greater in the gpx1, gpx4, and gpx7 mutants than in the wild type. The application of auxin increased GPX4 and GPX7 transcripts, but not GPX1 mRNAs in the roots of wild-type plants. The synthetic strigolactone GR24 and abscisic acid (ABA) decreased LRD to a similar extent in all genotypes, except gpx6, which showed increased sensitivity to ABA. These data not only demonstrate the importance of redox controls mediated by AtGPXs in the control of root architecture but they also show that the plastid-localized GPX1 and GPX7 isoforms are required for the hormone-mediated control of lateral root development.

  3. Deletion of glutathione peroxidase-2 inhibits azoxymethane-induced colon cancer development.

    Directory of Open Access Journals (Sweden)

    Mike F Müller

    Full Text Available The selenoprotein glutathione peroxidase-2 (GPx2 appears to have a dual role in carcinogenesis. While it protected mice from colon cancer in a model of inflammation-triggered carcinogenesis (azoxymethane and dextran sodium sulfate treatment, it promoted growth of xenografted tumor cells. Therefore, we analyzed the effect of GPx2 in a mouse model mimicking sporadic colorectal cancer (azoxymethane-treatment only. GPx2-knockout (KO and wild-type (WT mice were adjusted to an either marginally deficient (-Se, adequate (+Se, or supranutritional (++Se selenium status and were treated six times with azoxymethane (AOM to induce tumor development. In the -Se and ++Se groups, the number of tumors was significantly lower in GPx2-KO than in respective WT mice. On the +Se diet, the number of dysplastic crypts was reduced in GPx2-KO mice. This may be explained by more basal and AOM-induced apoptotic cell death in GPx2-KO mice that eliminates damaged or pre-malignant epithelial cells. In WT dysplastic crypts GPx2 was up-regulated in comparison to normal crypts which might be an attempt to suppress apoptosis. In contrast, in the +Se groups tumor numbers were similar in both genotypes but tumor size was larger in GPx2-KO mice. The latter was associated with an inflammatory and tumor-promoting environment as obvious from infiltrated inflammatory cells in the intestinal mucosa of GPx2-KO mice even without any treatment and characterized as low-grade inflammation. In WT mice the number of tumors tended to be lowest in +Se compared to -Se and ++Se feeding indicating that selenium might delay tumorigenesis only in the adequate status. In conclusion, the role of GPx2 and presumably also of selenium depends on the cancer stage and obviously on the involvement of inflammation.

  4. Molecular characterization and functional analysis of a glutathione peroxidase gene from Aphelenchoides besseyi (Nematoda: Aphelenchoididae).

    Science.gov (United States)

    Wang, Bu-Yong; Wen, Rong-Rong; Ma, Ling

    2017-09-26

    Aphelenchoides besseyi, the nematode agent of rice tip white disease, causes huge economic losses in almost all the rice-growing regions of the world. Glutathione peroxidase (GPx), an esophageal glands secretion protein, plays important roles in the parasitism, immune evasion, reproduction and pathogenesis of many plant-parasitic nematodes (PPNs). Therefore, GPx is a promising target for control A. besseyi. Here, the full-length sequence of the GPx gene from A. besseyi (AbGPx1) was cloned using the rapid amplification of cDNA ends method. The full-length 944 bp AbGPx1 sequence, which contains a 678 bp open reading frame, encodes a 225 amino acid protein. The deduced amino acid sequence of the AbGPxl shares highly homologous with other nematode GPxs, and showed the closest evolutionary relationship with DrGPx. In situ hybridization showed that AbGPx1 was constitutively expressed in the esophageal glands of A. besseyi, suggesting its potential roles in parasitism and reproduction. RNA interference (RNAi) was used to assess the functions of the AbGPx1 gene, and quantitative real-time PCR was used to monitor the RNAi effects. After treatment with dsRNA for 12 h, AbGPx1 expression levels and reproduction in the nematodes decreased compared with the same parameters in the control group; thus, the AbGPx1 gene is likely to be associated with the development, reproduction, and infection ability of A. besseyi. These findings may open new avenues towards nematode control.

  5. Differential regulation of glutathione peroxidase by selenomethionine and hyperoxia in endothelial cells.

    Science.gov (United States)

    Jornot, L; Junod, A F

    1995-01-01

    We have studied the effect of selenomethionine (SeMet) and hyperoxia on the expression of glutathione peroxidase (GP) in human umbilical vein endothelial cells. Incubation of HUVEC with 1 x 10(-6) M SeMet for 24 h and 48 h caused a 65% and 86% increase in GP activity respectively. The same treatment did not result in significant changes in GP gene transcription and mRNA levels. Pactamycin, a specific inhibitor of the initiation step of translation, prevented the rise in GP activity induced by SeMet and caused an increase in GP mRNA in both cells grown in normal and SeMet-supplemented medium. Interestingly, SeMet supplementation stimulated the recruitment of GP mRNA from an untranslatable pool on to polyribosomes, so that the concentration of GP mRNA in polyribosomal translatable pools was 50% higher in cells grown in SeMet-supplemented medium than in cells grown in normal medium. On the other hand, cells exposed to 95% O2 for 3 days in normal medium showed a 60%, 394% and 81% increase in GP gene transcription rate, mRNA levels and activity respectively. Hyperoxia also stabilized GP mRNA. Hyperoxic cells grown in SeMet-supplemented medium did not show any change in GP gene transcription and mRNA levels, but expressed an 81% and 100% increase in GP activity and amount of GP mRNA associated with polyribosomes respectively, when compared with hyperoxic cells maintained in normal medium. Thus, GP appeared to be regulated post-transcriptionally, most probably co-translationally, in response to selenium availability, and transcriptionally and post-transcriptionally in response to oxygen. Images Figure 1 Figure 2 Figure 4 Figure 7 Figure 8 PMID:7887914

  6. Overexpression of cellular glutathione peroxidase rescues homocyst(e)ine-induced endothelial dysfunction

    Science.gov (United States)

    Weiss, Norbert; Zhang, Ying-Yi; Heydrick, Stanley; Bierl, Charlene; Loscalzo, Joseph

    2001-01-01

    Homocyst(e)ine (Hcy) inhibits the expression of the antioxidant enzyme cellular glutathione peroxidase (GPx-1) in vitro and in vivo, which can lead to an increase in reactive oxygen species that inactivate NO and promote endothelial dysfunction. In this study, we tested the hypothesis that overexpression of GPx-1 can restore the normal endothelial phenotype in hyperhomocyst(e)inemic states. Heterozygous cystathionine β-synthase-deficient (CBS(−/+)) mice and their wild-type littermates (CBS(+/+)) were crossbred with mice that overexpress GPx-1 [GPx-1(tg+) mice]. GPx-1 activity was 28% lower in CBS(−/+)/GPx-1(tg−) compared with CBS(+/+)/GPx-1(tg−) mice (P < 0.05), and CBS(−/+) and CBS(+/+) mice overexpressing GPx-1 had 1.5-fold higher GPx-1 activity compared with GPx-1 nontransgenic mice (P < 0.05). Mesenteric arterioles of CBS(−/+)/GPx-1(tg−) mice showed vasoconstriction to superfusion with β-methacholine and bradykinin (P < 0.001 vs. all other groups), whereas nonhyperhomocyst(e)inemic mice [CBS(+/+)/GPx-1(tg−) and CBS(+/+)/GPx-1(tg+) mice] demonstrated dose-dependent vasodilation in response to both agonists. Overexpression of GPx-1 in hyperhomocyst(e)inemic mice restored the normal endothelium-dependent vasodilator response. Bovine aortic endothelial cells (BAEC) were transiently transfected with GPx-1 and incubated with dl-homocysteine (HcyH) or l-cysteine. HcyH incubation decreased GPx-1 activity in sham-transfected BAEC (P < 0.005) but not in GPx-1-transfected cells. Nitric oxide release from BAEC was significantly decreased by HcyH but not cysteine, and GPx-1 overexpression attenuated this decrease. These findings demonstrate that overexpression of GPx-1 can compensate for the adverse effects of Hcy on endothelial function and suggest that the adverse vascular effects of Hcy are at least partly mediated by oxidative inactivation of NO. PMID:11606774

  7. Molecular consequences of genetic variations in the glutathione peroxidase 1 selenoenzyme.

    Science.gov (United States)

    Zhuo, Pin; Goldberg, Marci; Herman, Lauren; Lee, Bao-Shiang; Wang, Hengbing; Brown, Rhonda L; Foster, Charles B; Peters, Ulrike; Diamond, Alan M

    2009-10-15

    Accumulating data have implicated the selenium-containing cytosolic glutathione peroxidase, GPx-1, as a determinant of cancer risk and a mediator of the chemopreventive properties of selenium. Genetic variants of GPx-1 have been shown to be associated with cancer risk for several types of malignancies. To investigate the relationship between GPx-1 enzyme activity and genotype, we measured GPx-1 enzyme activity and protein levels in human lymphocytes as a function of the presence of two common variations: a leucine/proline polymorphism at codon 198 and a variable number of alanine-repeat codons. Differences in GPx activity among these cell lines, as well as in the response to the low-level supplementation of the media with selenium, indicated that factors other than just genotype are significant in determining activity. To restrict the study to genotypic effects, human MCF-7 cells were engineered to exclusively express allelic variants representing a combination of either a codon 198 leucine or proline and either 5 or 7 alanine-repeat codons following transfection of GPx-1 expression constructs. Transfectants were selected and analyzed for GPx-1 enzyme activity and protein levels. GPx-1 with 5 alanines and a leucine at codon 198 showed a significantly higher induction when cells were incubated with selenium and showed a distinct pattern of thermal denaturation as compared with GPx-1 encoded by the other examined alleles. The collective data obtained using both lymphocytes and MCF-7 indicate that both intrinsic and extrinsic factors cooperate to ultimately determine the levels of this enzyme available to protect cells against DNA damage and mutagenesis.

  8. Glutathione peroxidase mimic ebselen improves glucose-stimulated insulin secretion in murine islets.

    Science.gov (United States)

    Wang, Xinhui; Yun, Jun-Won; Lei, Xin Gen

    2014-01-10

    Glutathione peroxidase (GPX) mimic ebselen and superoxide dismutase (SOD) mimic copper diisopropylsalicylate (CuDIPs) were used to rescue impaired glucose-stimulated insulin secretion (GSIS) in islets of GPX1 and(or) SOD1-knockout mice. Ebselen improved GSIS in islets of all four tested genotypes. The rescue in the GPX1 knockout resulted from a coordinated transcriptional regulation of four key GSIS regulators and was mediated by the peroxisome proliferator-activated receptor gamma coactivator 1 alpha (PGC-1α)-mediated signaling pathways. In contrast, CuDIPs improved GSIS only in the SOD1 knockout and suppressed gene expression of the PGC-1α pathway. Islets from the GPX1 and(or) SOD1 knockout mice provided metabolically controlled intracellular hydrogen peroxide (H2O2) and superoxide conditions for the present study to avoid confounding effects. Bioinformatics analyses of gene promoters and expression profiles guided the search for upstream signaling pathways to link the ebselen-initiated H2O2 scavenging to downstream key events of GSIS. The RNA interference was applied to prove PGC-1α as the main mediator for that link. Our study revealed a novel metabolic use and clinical potential of ebselen in rescuing GSIS in the GPX1-deficient islets and mice, along with distinct differences between the GPX and SOD mimics in this regard. These findings highlight the necessities and opportunities of discretional applications of various antioxidant enzyme mimics in treating insulin secretion disorders. REBOUND TRACK: This work was rejected during standard peer review and rescued by Rebound Peer Review (Antioxid Redox Signal 16: 293-296, 2012) with the following serving as open reviewers: Regina Brigelius-Flohe, Vadim Gladyshev, Dexing Hou, and Holger Steinbrenner.

  9. Impact of glutathione peroxidase-1 deficiency on macrophage foam cell formation and proliferation: implications for atherogenesis.

    Directory of Open Access Journals (Sweden)

    Fei Cheng

    Full Text Available Clinical and experimental evidence suggests a protective role for the antioxidant enzyme glutathione peroxidase-1 (GPx-1 in the atherogenic process. GPx-1 deficiency accelerates atherosclerosis and increases lesion cellularity in ApoE(-/- mice. However, the distribution of GPx-1 within the atherosclerotic lesion as well as the mechanisms leading to increased macrophage numbers in lesions is still unknown. Accordingly, the aims of the present study were (1 to analyze which cells express GPx-1 within atherosclerotic lesions and (2 to determine whether a lack of GPx-1 affects macrophage foam cell formation and cellular proliferation. Both in situ-hybridization and immunohistochemistry of lesions of the aortic sinus of ApoE(-/- mice after 12 weeks on a Western type diet revealed that both macrophages and - even though to a less extent - smooth muscle cells contribute to GPx-1 expression within atherosclerotic lesions. In isolated mouse peritoneal macrophages differentiated for 3 days with macrophage-colony-stimulating factor (MCSF, GPx-1 deficiency increased oxidized low density-lipoprotein (oxLDL induced foam cell formation and led to increased proliferative activity of peritoneal macrophages. The MCSF- and oxLDL-induced proliferation of peritoneal macrophages from GPx-1(-/-ApoE(-/- mice was mediated by the p44/42 MAPK (p44/42 mitogen-activated protein kinase, namely ERK1/2 (extracellular-signal regulated kinase 1/2, signaling pathway as demonstrated by ERK1/2 signaling pathways inhibitors, Western blots on cell lysates with primary antibodies against total and phosphorylated ERK1/2, MEK1/2 (mitogen-activated protein kinase kinase 1/2, p90RSK (p90 ribosomal s6 kinase, p38 MAPK and SAPK/JNK (stress-activated protein kinase/c-Jun N-terminal kinase, and immunohistochemistry of mice atherosclerotic lesions with antibodies against phosphorylated ERK1/2, MEK1/2 and p90RSK. Representative effects of GPx-1 deficiency on both macrophage proliferation and

  10. Investigation of glutathione peroxidase activity in chicken meat under different experimental conditions

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    Alexandre José Cichoski

    2012-12-01

    Full Text Available Due to the fact that previous studies on the enzymatic activity of Glutathione peroxidase (GSH-Px diverge widely in their methodology and results, this study aimed to investigate the influence of different analytical conditions on GSH-Px activity in chicken thighs from broilers that were fed different diets with different sources and concentrations of selenium. GSH-Px activity was evaluated six hours after slaughter and 120 days after frozen storage at -18 ºC. The different analytical conditions included time of pre-incubation (0, 10 and 30 minutes, reaction medium, types of substrate (H2O2 (0.72 mM, 7.2 mM, and 72 mM and Terc-butil hydroperoxide 15 mM, and different buffer concentrations (buffer 1, potassium phosphate 50 mM pH 7.0 + EDTA 1 mM + mercaptoethanol 1 mM, and buffer 2, tris-HCl 50 mM pH 7.6 + EDTA 1 mM + mercapthanol 5 mM. The results show that the highest GSH-Px activity was observed when enzyme and substrate were in contact at 22 ºC without any pre-incubation, and that, when used at concentrations above 0.72 mM, hydrogen peroxide saturated the GSH-Px enzyme and inhibited its activity. The enzyme presented higher affinity to hydrogen peroxide when compared to terc-butil peroxide, and the addition of a buffer containing mercaptoethanol did not increase GSH-Px enzymatic activity. The activity of GSH-Px was not influenced by the source and concentration of selenium in the diet either. The obtained results allowed the determination of the best temperature of contact between the enzyme and substrate (22 ºC, the optimum concentration, and the type of substrate and buffer to be used. This information is extremely useful for future studies on GSH-Px activity in meat due to the divergence and little information found in the literature.

  11. Hyperoxia, unlike phorbol ester, induces glutathione peroxidase through a protein kinase C-independent mechanism.

    Science.gov (United States)

    Jornot, L; Junod, A F

    1997-01-01

    Human selenium-dependent glutathione peroxidase (GP) is implicated as a mechanism of resistance against oxygen free radicals. The 5' flanking sequence upstream from the coding region of GP contained an oxygen-responsive element termed ORE1 that is responsive to hypoxia, as well as several copies of the activator protein-1 (AP-1)- and AP-1-like-binding sites. In this study, we sought to define the molecular events that lead to GP gene transcription in response to hyperoxia in human umbilical-vein endothelial cells, and asked whether such induction is mimicked and sustained by activation of protein kinase C (PKC) by phorbol esters. Treatment of cells with 100 nM phorbol 12,13-dibutyrate (PdBu) induced a delayed (24-48 h) but significant (2-fold) increase in steady-state GP mRNA levels. Steady-state GP mRNA levels also rose after exposure to 95% O2, again after considerable delay (48-72 h). For both PdBu and oxygen, induction was transcriptionally regulated, as demonstrated by nuclear run-on experiments. The simulations by PdBu and oxygen were additive. In contrast with PdBu, hyperoxia did not stimulate translocation of PKC from the cytosol to the particulate fraction, although the specific activity of both cytosolic and particulate-associated PKC was increased 2-fold in cells exposed to 95% O2 for 5 days. In addition, gel mobility-shift assays using double-stranded tumour-promoting-agent-responsive element (TRE) and nuclear extracts derived from phorbol- and oxygen-treated cells revealed that PdBu, but not hyperoxia, increased AP-1 DNA-binding activity. On the other hand, the up-regulation of GP expression by oxygen could not be accounted for by the ORE1 core sequence, since no specific protein-DNA binding activity could be detected using nuclear extracts from hyperoxic cells and ORE1. Taken together, these results suggest that there may be different molecular mechanisms controlling GP expression. After exposure to PdBu, GP undergoes transcriptional activation via a

  12. Silencing of glutathione peroxidase 3 through DNA hypermethylation is associated with lymph node metastasis in gastric carcinomas.

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    Dun-Fa Peng

    Full Text Available Gastric cancer remains the second leading cause of cancer-related death in the world. H. pylori infection, a major risk factor for gastric cancer, generates high levels of reactive oxygen species (ROS. Glutathione peroxidase 3 (GPX3, a plasma GPX member and a major scavenger of ROS, catalyzes the reduction of hydrogen peroxide and lipid peroxides by reduced glutathione. To study the expression and gene regulation of GPX3, we examined GPX3 gene expression in 9 gastric cancer cell lines, 108 primary gastric cancer samples and 45 normal gastric mucosa adjacent to cancers using quantitative real-time RT-PCR. Downregulation or silencing of GPX3 was detected in 8 of 9 cancer cell lines, 83% (90/108 gastric cancers samples, as compared to non-tumor adjacent normal gastric samples (P<0.0001. Examination of GPX3 promoter demonstrated DNA hypermethylation (≥ 10% methylation level determined by Bisulfite Pyrosequencing in 6 of 9 cancer cell lines and 60% of gastric cancer samples (P = 0.007. We also detected a significant loss of DNA copy number of GPX3 in gastric cancers (P<0.001. Treatment of SNU1 and MKN28 cells with 5-Aza-2' Deoxycytidine restored the GPX3 gene expression with a significant demethylation of GPX3 promoter. The downregulation of GPX3 expression and GPX3 promoter hypermethylation were significantly associated with gastric cancer lymph node metastasis (P = 0.018 and P = 0.029, respectively. We also observed downregulation, DNA copy number losses, and promoter hypermethylation of GPX3 in approximately one-third of tumor-adjacent normal gastric tissue samples, suggesting the presence of a field defect in areas near tumor samples. Reconstitution of GPX3 in AGS cells reduced the capacity of cell migration, as measured by scratch wound healing assay. Taken together, the dysfunction of GPX3 in gastric cancer is mediated by genetic and epigenetic alterations, suggesting impairment of mechanisms that regulate ROS and its possible involvement in

  13. Glutathione turnover in 14 rat tissues

    International Nuclear Information System (INIS)

    Potter, D.W.; Tran, T.

    1990-01-01

    GSH is a tripeptide found in all tissues and is important in maintaining cellular redox status. First-order rate constants for GSH turnover were determined for various tissues of Fischer male rats. Animals were administered [ 35 S]Cys by tail vein injection and GSH turnover was estimated by the decrease in GSH specific activity following incorporation of Cys, 1-102 hr after administration. Tissue nonprotein sulfhydryls (NPSH) were detected by Ellman's assay and compared with GSH and Cys concentrations determined by HPLC with electrochemical detection. [ 35 S]GSH was analyzed by HPLC equipped with a flow-through radioactivity detector. Although total GSH and Cys were usually slightly lower than NPSH concentrations for the tissues examined, both assay systems gave comparable results. An exception was the glandular stomach which had approximately 2-fold higher NPSH. Liver and kidney had rapid turnover rates with GSH half-lives between 2-5 hr, while heart and skeletal muscle tissue had half-lives of 80-90 hr. Turnover in the blood was slowest, with a half-life of 170 hr. Gastrointestinal tract tissues were shown to have intermediate turnover rates of the following order: glandular stomach > duodenum = small intestine = caecum = large intestine = colon > forestomach. GSH half-life in lung and skin was approximately 45 hr. These studies indicate that tissues utilize GSH at markedly different rates

  14. Chemical form of selenium affects its uptake, transport, and glutathione peroxidase activity in the human intestinal Caco-2 cell model.

    Science.gov (United States)

    Zeng, Huawei; Jackson, Matthew I; Cheng, Wen-Hsing; Combs, Gerald F

    2011-11-01

    Determining the effect of selenium (Se) chemical form on uptake, transport, and glutathione peroxidase activity in human intestinal cells is critical to assess Se bioavailability at nutritional doses. In this study, we found that two sources of L-selenomethionine (SeMet) and Se-enriched yeast each increased intracellular Se content more effectively than selenite or methylselenocysteine (SeMSC) in the human intestinal Caco-2 cell model. Interestingly, SeMSC, SeMet, and digested Se-enriched yeast were transported at comparable efficacy from the apical to basolateral sides, each being about 3-fold that of selenite. In addition, these forms of Se, whether before or after traversing from apical side to basolateral side, did not change the potential to support glutathione peroxidase (GPx) activity. Although selenoprotein P has been postulated to be a key Se transport protein, its intracellular expression did not differ when selenite, SeMSC, SeMet, or digested Se-enriched yeast was added to serum-contained media. Taken together, our data show, for the first time, that the chemical form of Se at nutritional doses can affect the absorptive (apical to basolateral side) efficacy and retention of Se by intestinal cells; but that, these effects are not directly correlated to the potential to support GPx activity.

  15. The effect of seedling chilling on glutathione content, catalase and peroxidase activity in Brassica oleracea L. var. italica

    Directory of Open Access Journals (Sweden)

    Renata Wojciechowska

    2013-09-01

    Full Text Available The study was designed to determine the possible relationship between Brassica oleracea var. italica seedlings stored at 2°C in the dark for seven and fourteen days, respectively, and the level of certain antioxidant parameters in particular organs. A parallel objective of the experiment was to determine if the reaction of seedlings to low temperature might be persistent in fully developed plants until harvest time. After 14 days of chilling a significant increase in the glutathione content was observed in the seedling leaves in comparison to the non-chilled plants. During vegetation in field conditions this effect was maintained in leaves up to the stage of formation of flower buds. At harvest the highest content of glutathione was demonstrated in broccoli heads, obtained from plants, which were previously chilled in the seedling phase for two weeks. Peroxidase activity in broccoli seedlings increased each year of the three-year study due to the duration of the cooling time, whereas in the case of catalase the changes were not so distinct. At harvest time the activity of both enzymes in the leaves and flower buds fluctuated according to the particular year of study.

  16. Effects of polymorphisms in vitamin E-, vitamin C-, and glutathione peroxidase-related genes on serum biomarkers and associations with glaucoma

    Science.gov (United States)

    To study the association of selected polymorphism in genes related to vitamin E, vitamin C, and glutathione peroxidase with these biomarkers and primary open-angle glaucoma (POAG) risk. A case-control study matched for age, sex, and bodyweight was undertaken. Two hundred fifty POAG cases and 250 con...

  17. Glutathione.

    Science.gov (United States)

    Noctor, Graham; Queval, Guillaume; Mhamdi, Amna; Chaouch, Sejir; Foyer, Christine H

    2011-01-01

    Glutathione is a simple sulfur compound composed of three amino acids and the major non-protein thiol in many organisms, including plants. The functions of glutathione are manifold but notably include redox-homeostatic buffering. Glutathione status is modulated by oxidants as well as by nutritional and other factors, and can influence protein structure and activity through changes in thiol-disulfide balance. For these reasons, glutathione is a transducer that integrates environmental information into the cellular network. While the mechanistic details of this function remain to be fully elucidated, accumulating evidence points to important roles for glutathione and glutathione-dependent proteins in phytohormone signaling and in defense against biotic stress. Work in Arabidopsis is beginning to identify the processes that govern glutathione status and that link it to signaling pathways. As well as providing an overview of the components that regulate glutathione homeostasis (synthesis, degradation, transport, and redox turnover), the present discussion considers the roles of this metabolite in physiological processes such as light signaling, cell death, and defense against microbial pathogen and herbivores.

  18. Roles of catalase and glutathione peroxidase in the tolerance of a pulmonate gastropod to anoxia and reoxygenation.

    Science.gov (United States)

    Welker, Alexis F; Moreira, Daniel C; Hermes-Lima, Marcelo

    2016-07-01

    Humans and most mammals suffer severe damage when exposed to ischemia and reperfusion episodes due to an overproduction of reactive oxygen species (ROS). In contrast, several hypoxia/anoxia-tolerant animals survive very similar situations. We evaluated herein the redox metabolism in the anoxia-tolerant land snail Helix aspersa after catalase inhibition by 3-amino-1,2,4-triazole (ATZ) injection during a cycle of wide and abrupt change in oxygen availability. The exposure to anoxia for 5 h caused a change of only one of several parameters related to free radical metabolism: a rise in selenium-dependent glutathione peroxidase (Se-GPX) activity in muscle of both saline- and ATZ-injected animals (by 1.9- and 1.8-fold, respectively). Catalase suppression had no effect in animals under normoxia or anoxia. However, during reoxygenation catalase suppression kept high levels of muscle Se-GPX activity (twofold higher than in saline-injected snails up to 30 min reoxygenation) and induced the increase in hepatopancreas SOD activity (by 22 %), indicating higher levels of ROS in both organs than in saline-injected animals. Additionally, catalase-suppressed snails showed 12 % higher levels of carbonyl protein-a sign of mild oxidative stress-in muscle during reoxygenation than those animals with intact catalase. No changes were observed in glutathione parameters (GSH, GSSG and GSSG:GSH ratio), TBARS, and GST activity in any of the experimental groups, in both organs. These results indicate that catalase inhibition inflicts changes in the free radical metabolism during reoxygenation, prompting a stress-response that is a reorganization in other enzymatic antioxidant defenses to minimize alterations in the redox homeostasis in land snails.

  19. Glutathione depletion in tissues after administration of buthionine sulphoximine

    International Nuclear Information System (INIS)

    Minchinton, A.I.; Rojas, A.; Smith, A.; Soranson, J.A.; Shrieve, D.C.; Jones, N.R.; Bremner, J.C.

    1984-01-01

    Buthionine sulphoximine (BSO) an inhibitor of glutathione (GSH) biosynthesis, was administered to mice in single and repeated doses. The resultant pattern of GSH depletion was studied in liver, kidney, skeletal muscle and three types of murine tumor. Liver and kidney exhibited a rapid depletion of GSH. Muscle was depleted to a similar level, but at a slower rate after a single dose. All three tumors required repeated administration of BSO over several days to obtain a similar degree of depletion to that shown in the other tissues

  20. Tissue Printing to Visualize Polyphenol Oxidase and Peroxidase in Vegetables, Fruits, and Mushrooms

    Science.gov (United States)

    Melberg, Amanda R.; Flurkey, William H.; Inlow, Jennifer K.

    2009-01-01

    A simple tissue-printing procedure to determine the tissue location of the endogenous enzymes polyphenol oxidase and peroxidase in a variety of vegetables, fruits, and mushrooms is described. In tissue printing, cell contents from the surface of a cut section of the tissue are transferred to an adsorptive surface, commonly a nitrocellulose…

  1. Expression of glutathione peroxidase 2 is associated with not only early hepatocarcinogenesis but also late stage metastasis

    International Nuclear Information System (INIS)

    Suzuki, Shugo; Pitchakarn, Pornsiri; Ogawa, Kumiko; Naiki-Ito, Aya; Chewonarin, Teera; Punfa, Wanisa; Asamoto, Makoto; Shirai, Tomoyuki; Takahashi, Satoru

    2013-01-01

    Understanding of mechanisms of cancer progression is very important for reduction of cancer mortality. Of six rat hepatocellular carcinoma (HCC) cell lines, differing in their metastatic potential to the lung after inoculation into the tail vein of nude mice, the most metastatic featured particular overexpression of glutathione peroxidase 2 (GPX2). Therefore, we analyzed the influence of interference in highly metastatic L2 cells by siRNA transfection. Gpx2 siRNA significantly inhibited cell proliferation at 24 and 48 h time points with induction of apoptosis but not cell cycle arrest. High expression of mutated p53 was detected in all HCC cell lines, with reduction in Gpx2 siRNA-transfected cells. Migration and invasion in vitro were also suppressed as compared to control siRNA-transfected cells and secretion of matrix metalloproteinase 9 was reduced. In vivo, the numbers and areas of metastatic nodules per area in the lungs were significantly reduced in the mice inoculated with Gpx2 siRNA-transfected cells as compared to control siRNA-transfected cells. In conclusion, expression of GPX2 is associated with cancer metastasis from rat HCCs both in vitro and in vivo. Together with immunohistochemical findings of elevated expression in rat and also human liver lesions, the results point to important roles in hepatocarcinogenesis

  2. Effects of acetylcysteine and probucol on contrast medium-induced depression of intrinsic renal glutathione peroxidase activity in diabetic rats.

    Science.gov (United States)

    Yen, Hsueh-Wei; Lee, Hsiang-Chun; Lai, Wen-Te; Sheu, Sheng-Hsiung

    2007-04-01

    Antioxidants such as N-acetylcysteine and probucol have been used to protect patients from contrast media-induced nephrotoxicity. The mechanisms underlying these protective effects are not well understood. We hypothesized that acetylcysteine and probucol alter the activity of endogenous antioxidant enzyme activity. Four weeks after induction of diabetes with streptozotocin, diabetic and nondiabetic rats were divided into three groups. Group 1 rats did not receive any antioxidant agents. Group 2 rats were treated with acetylcysteine and group 3 rats with probucol for 1 week before injection of the contrast medium diatrizoate (DTZ). We found that diabetic rats had higher renal glutathione peroxidase (GPx) activity than normal rats. DTZ suppressed renal GPx activity significantly in both group 1 diabetic and normal rats. Interestingly, renal GPx activity in both diabetic and normal rats pretreated with acetylcysteine or probucol was not inhibited by DTZ. Renal superoxide dismutase (SOD) increased significantly in normal rats after DTZ injection, but not in diabetic rats. Finally, acetylcysteine or probucol did not significantly influence renal SOD. These findings suggest that the renal protective effects of acetylcysteine and probucol against contrast-induced oxidative stress and nephrotoxicity may be mediated by altering endogenous GPx activity.

  3. The importance of Arabidopsis glutathione peroxidase 8 for protecting Arabidopsis plant and E. coli cells against oxidative stress.

    Science.gov (United States)

    Gaber, Ahmed

    2014-01-01

    Glutathione peroxidases (GPXs) are major family of the reactive oxygen species (ROS) scavenging enzymes. Recently, database analysis of the Arabidopsis genome revealed a new open-reading frame, thus increasing the total number of AtGPX gene family to eight (AtGPX1-8). The effect of plant hormones like; i. e. salicylic acid (SA), jasmonic acid (JA), abscisic acid (ABA), indoleacetic acid (IAA), and mannitol on the expression of the genes confirm that the AtGPX genes family is regulated by multiple signaling pathways. The survival rate of AtGPX8 knockout plants (KO8) was significantly decreased under heat stress compared with the wild type. Moreover, the content of malondialdehyde (MDA) and protein oxidation was significantly increased in the KO8 plant cells under heat stress. Results indicating that the deficiency of AtGPX8 accelerates the progression of oxidative stress in KO8 plants. On the other hand, the overexpression of AtGPX8 in E. coli cells enhance the growth of the recombinant enzyme on media supplemented with 0.2 mM cumene hydroperoxide, 0.3 mM H 2O 2 or 600 mM NaCl.

  4. Ablation of the Ferroptosis Inhibitor Glutathione Peroxidase 4 in Neurons Results in Rapid Motor Neuron Degeneration and Paralysis.

    Science.gov (United States)

    Chen, Liuji; Hambright, William Sealy; Na, Ren; Ran, Qitao

    2015-11-20

    Glutathione peroxidase 4 (GPX4), an antioxidant defense enzyme active in repairing oxidative damage to lipids, is a key inhibitor of ferroptosis, a non-apoptotic form of cell death involving lipid reactive oxygen species. Here we show that GPX4 is essential for motor neuron health and survival in vivo. Conditional ablation of Gpx4 in neurons of adult mice resulted in rapid onset and progression of paralysis and death. Pathological inspection revealed that the paralyzed mice had a dramatic degeneration of motor neurons in the spinal cord but had no overt neuron degeneration in the cerebral cortex. Consistent with the role of GPX4 as a ferroptosis inhibitor, spinal motor neuron degeneration induced by Gpx4 ablation exhibited features of ferroptosis, including no caspase-3 activation, no TUNEL staining, activation of ERKs, and elevated spinal inflammation. Supplementation with vitamin E, another inhibitor of ferroptosis, delayed the onset of paralysis and death induced by Gpx4 ablation. Also, lipid peroxidation and mitochondrial dysfunction appeared to be involved in ferroptosis of motor neurons induced by Gpx4 ablation. Taken together, the dramatic motor neuron degeneration and paralysis induced by Gpx4 ablation suggest that ferroptosis inhibition by GPX4 is essential for motor neuron health and survival in vivo. © 2015 by The American Society for Biochemistry and Molecular Biology, Inc.

  5. Effects of intracellular chelatable iron and oxidative stress on transcription of classical cellular glutathione peroxidase gene in murine erythroleukemia cells

    International Nuclear Information System (INIS)

    Fuchs, O.

    1997-01-01

    The effect of intracellular chelatable iron levels and of oxidative stress on nuclear classical cellular glutathione peroxidase (GSHPx-1) RNA nascent chain elongation (run-on transcription) and on the stability of cytoplasmic GSHPx-1 mRNA was investigated in murine erythroleukemia (MEL) cells. The amount in the intracellular low molecular mass iron pool was changed by incubation of MEL cells transformed by Friend virus with iron donors or iron chelators. Transcription in vitro in isolated nuclei from treated cells showed that the treatment with chelators (desferrioxamine (DFO), pyridoxal isonicotinoyl hydrazone) decrease the rate of nuclear GSHPx-1 RNA nascent chain elongation in both un-induced and with 5 mmol hexamethylenebisacetamide to erythroid differentiation induced MEL cells. Iron donors (diferric transferrin,, Fe-PIH or their combination) and t-butyl hydroperoxide (t-BuOOH) had the opposite effect on GSHPx-1 gene transcription in run-on experiments. On the other hand, 50 μmol DFO or 2.5 μmol t-BuOOH did not change the stability of cytoplasmic GSHPx-1 mRNA in both un-induced and induced MEL cells treated with 5 μmol actinomycin D and with or without these agents for 9 h. These findings indicate that iron and oxidative stress play their role at the transcriptional level of GSHPx-1 gene expression. (author)

  6. The Small Glutathione Peroxidase Mimic 5P May Represent a New Strategy for the Treatment of Liver Cancer.

    Science.gov (United States)

    Yin, Juxin; Wang, Bingmei; Zhu, Xuejun; Qu, Xiaonan; Huang, Yi; Lv, Shaowu; Mu, Ying; Luo, Guimin

    2017-09-08

    Glutathione peroxidase (GPx) is an antioxidant protein containing selenium. Owing to the limitations of native GPx, considerable efforts have been made to develop GPx mimics. Here, a short 5-mer peptides (5P) was synthesized and characterized using matrix-assisted laser desorption ionization time-of-flight mass spectrometry. Enzyme coupled assays were used to evaluate GPx activity. The cell viability and apoptosis of H22 cells were tested, and mice bearing H22 cell-derived tumors were used to determine the effects of 5P on tumor inhibition. In comparison with other enzyme models, 5P provided a suitable substrate with proper catalytic site positions, resulting in enhanced catalytic activity. In our mouse model, 5P showed excellent inhibition of tumor growth and improved immunity. In summary, our findings demonstrated the design and synthesis of the small 5P molecule, which inhibited tumor growth and improved immunity. Notably, 5P could inhibit tumor growth without affecting normal growth. Based on these advantages, the novel mimic may have several clinical applications.

  7. Halide peroxidase in tissues that interact with bacteria in the host squid Euprymna scolopes.

    Science.gov (United States)

    Small, A L; McFall-Ngai, M J

    1999-03-15

    An enzyme with similarities to myeloperoxidase, the antimicrobial halide peroxidase in mammalian neutrophils, occurs abundantly in the light organ tissue of Euprymna scolopes, a squid that maintains a beneficial association with the luminous bacterium Vibrio fischeri. Using three independent assays typically applied to the analysis of halide peroxidase enzymes, we directly compared the activity of the squid enzyme with that of human myeloperoxidase. One of these methods, the diethanolamine assay, confirmed that the squid peroxidase requires halide ions for its activity. The identification of a halide peroxidase in a cooperative bacterial association suggested that this type of enzyme can function not only to control pathogens, but also to modulate the interactions of host animals with their beneficial partners. To determine whether the squid peroxidase functions under both circumstances, we examined its distribution in a variety of host tissues, including those that typically interact with bacteria and those that do not. Tissues interacting with bacteria included those that have specific cooperative associations with bacteria (i.e., the light organ and accessory nidamental gland) and those that have transient nonspecific interactions with bacteria (i.e., the gills, which clear the cephalopod circulatory system of invading microorganisms). These bacteria-associated tissues were compared with the eye, digestive gland, white body, and ink-producing tissues, which do not typically interact directly with bacteria. Peroxidase enzyme assays, immunocytochemical localization, and DNA-RNA hybridizations showed that the halide-dependent peroxidase is consistently expressed in high concentration in tissues that interact bacteria. Elevated levels of the peroxidase were also found in the ink-producing tissues, which are known to have enzymatic pathways associated with antimicrobial activity. Taken together, these data suggest that the host uses a common biochemical response to

  8. Modulation of the Activities of Catalase, Cu-Zn, Mn Superoxide Dismutase, and Glutathione Peroxidase in Adipocyte from Ovariectomised Female Rats with Metabolic Syndrome

    Directory of Open Access Journals (Sweden)

    Rebeca Cambray Guerra

    2014-01-01

    Full Text Available The aim of this study was to evaluate the association between estrogen removal, antioxidant enzymes, and oxidative stress generated by obesity in a MS female rat model. Thirty two female Wistar rats were divided into 4 groups: Control (C, MS, MS ovariectomized (Ovx, and MS Ovx plus estradiol (E2. MS was induced by administering 30% sucrose to drinking water for 24 weeks. After sacrifice, intra-abdominal fat was dissected; adipocytes were isolated and lipid peroxidation, non-enzymatic antioxidant capacity, and the activities of Cu-Zn and Mn superoxide dismutase (SOD, catalase (CAT, and glutathione peroxidase (GPx were determined. There were no significant differences in the activities of Cu-Zn, Mn SOD, CAT, and GPx between the C and MS groups, but in the MS Ovx group there was a statistically significant decrease in the activities of these enzymes when compared to MS and MS Ovx+E2. The increased lipid peroxidation and nonenzymatic antioxidant capacity found in MS Ovx was significantly decreased when compared to MS and MS Ovx+E2. In conclusion, the removal of E2 by ovariectomy decreases the activity of the antioxidant enzymes in the intra-abdominal tissue of MS female rats; this is reflected by increased lipid peroxidation and decreased nonenzymatic antioxidant capacity.

  9. Plasma interleukin-6 levels, glutathione peroxidase and isoprostane in obese women before and after weight loss. Association with cardiovascular risk factors.

    Science.gov (United States)

    Bougoulia, Maria; Triantos, Athanassios; Koliakos, George

    2006-01-01

    To evaluate the levels of Interleukin-6 (IL-6), glutathione peroxidase and isoprostane in obese women and their association with markers of cardiovascular risk factors before and after weight loss. 36 healthy obese women of reproductive age (group A: age (mean+/-SD) 35.4+/-9.2 years, Body Mass Index (BMI) 38.5+/-7 kg/m2) and 30 healthy, normal weight women (group B: age mean+/-SD 34.9+/-7.4 y., BMI 24+/-1.1 kg/m2) were included in the study. Glucose tolerance was normal in all participating women. Il-6, glutathione peroxidase and isoprostane, C-Reactive Protein (CRP), insulin, fasting plasma glucose, HOMA-IR as well as the lipid profile were evaluated. Body weight, BMI, Waist to Hip ratio (W/H) ratio, Waist Circumference (WC), %free fat mass and the %fat mass were also measured. A hypo-caloric diet was prescribed for the obese women and all participants were re-examined after six months. In obese women after weight loss, anthropometric obesity markers (BMI, W/H ratio), %fat, lipid profile, insulin levels and inflammation indices such as IL-6 and CRP, the oxidative stress index isoprostane, as well as glutathione peroxidase were significantly ameliorated. The levels of serum glutathione peroxidase activity were negatively correlated with IL-6 levels and were significantly increased after weight reduction. In obese women there was an association between IL-6 levels and the values of %fat, %free fat mass, insulin and HOMA-IR before and after weight loss. Weight loss is related to reduction of oxidative stress and inflammation; this beneficial effect could possibly be translated into reduction of cardiovascular risk in obese individuals.

  10. Construction of a subtractive library from hexavalent chromium treated winter flounder (Pseudopleuronectes americanus) reveals alterations in non-selenium glutathione peroxidases

    International Nuclear Information System (INIS)

    Chapman, Laura M.; Roling, Jonathan A.; Bingham, Lacey K.; Herald, Matt R.; Baldwin, William S.

    2004-01-01

    Chromium is released during several industrial processes and has accumulated in some estuarine areas. Its effects on mammals have been widely studied, but relatively little information is available on its effects on fish. Gene expression changes are useful biomarkers that can provide information about toxicant exposure and effects, as well as the health of an organism and its ability to adapt to its surroundings. Therefore, we investigated the effects of Cr(VI) on gene expression in the sediment dwelling fish, winter flounder (Pseudopleuronectes americanus). Winter flounder ranging from 300 to 360 g were injected i.p. with Cr(VI) as chromium oxide at 25 μg/kg chromium in 0.15N KCl. Twenty-four hours following injections, winter flounder were euthanized with MS-222 and the livers were excised. Half of the livers were used to make cytosol and the other half were used to isolate mRNA for subtractive hybridization. Subtractive clones obtained were spotted onto nylon filters, which revealed several genes with potentially altered expression due to Cr(VI), including an α class GST, 1-Cys peroxiredoxin (a non-selenium glutathione peroxidase), a P-450 2X subfamily member, two elongation factors (EF-1 gamma and EF-2), and complement component C3. Semi-quantitative RT-PCR was performed and confirmed that Cr(VI) down-regulated complement component C3, an EST, and two potential glutathione peroxidases, GSTA3 and 1-Cys peroxiredoxin. In addition, cytosolic GSH peroxidase activity was reduced, and silver stained SDS-PAGE gels from glutathione-affinity purified cytosol demonstrated that a 27.1 kDa GSH-binding protein was down-regulated greater than 50%. Taken together, Cr(VI) significantly altered the expression of several genes including two potential glutathione peroxidases in winter flounder

  11. Modular evolution of glutathione peroxidase genes in association with different biochemical properties of their encoded proteins in invertebrate animals

    Directory of Open Access Journals (Sweden)

    Zo Young-Gun

    2009-04-01

    Full Text Available Abstract Background Phospholipid hydroperoxide glutathione peroxidases (PHGPx, the most abundant isoforms of GPx families, interfere directly with hydroperoxidation of lipids. Biochemical properties of these proteins vary along with their donor organisms, which has complicated the phylogenetic classification of diverse PHGPx-like proteins. Despite efforts for comprehensive analyses, the evolutionary aspects of GPx genes in invertebrates remain largely unknown. Results We isolated GPx homologs via in silico screening of genomic and/or expressed sequence tag databases of eukaryotic organisms including protostomian species. Genes showing strong similarity to the mammalian PHGPx genes were commonly found in all genomes examined. GPx3- and GPx7-like genes were additionally detected from nematodes and platyhelminths, respectively. The overall distribution of the PHGPx-like proteins with different biochemical properties was biased across taxa; selenium- and glutathione (GSH-dependent proteins were exclusively detected in platyhelminth and deuterostomian species, whereas selenium-independent and thioredoxin (Trx-dependent enzymes were isolated in the other taxa. In comparison of genomic organization, the GSH-dependent PHGPx genes showed a conserved architectural pattern, while their Trx-dependent counterparts displayed complex exon-intron structures. A codon for the resolving Cys engaged in reductant binding was found to be substituted in a series of genes. Selection pressure to maintain the selenocysteine codon in GSH-dependent genes also appeared to be relaxed during their evolution. With the dichotomized fashion in genomic organizations, a highly polytomic topology of their phylogenetic trees implied that the GPx genes have multiple evolutionary intermediate forms. Conclusion Comparative analysis of invertebrate GPx genes provides informative evidence to support the modular pathways of GPx evolution, which have been accompanied with sporadic

  12. Blood Haematology, Serum Thyroid Hormones and Glutathione Peroxidase Status in Kacang Goats Fed Inorganic Iodine and Selenium Supplemented Diets

    Directory of Open Access Journals (Sweden)

    Z. A. Aghwan

    2013-11-01

    Full Text Available The effects of dietary supplementation of selenium (Se, iodine (I, and a combination of both on the blood haematology, serum free thyroxine (FT4 and free triiodothyronine (FT3 hormones and glutathione peroxidase enzyme (GSH-Px activity were examined on twenty four (7 to 8 months old, 22±1.17 kg live weight Kacang crossbred male goats. Animals were randomly assigned to four dietary treatments (6 animals in each group. Throughout 100 d of feeding trial, the animals of control group (CON received a basal diet, while the other three groups were offered basal diet supplemented with 0.6 mg/kg diet DM Se (SS, or 0.6 mg/kg diet DM I (PI, or a combination of both Se and I, each at 0.6 mg/kg diet DM (SSPI. The haematological attributes which are haemoglobin (Hb, red blood cell (RBC, packed cell volume (PCV, mean cell volume (MCV, white blood cells (WBC, band neutrophils (B Neut, segmented neutrophils (S Neut, lymphocytes (Lymph, monocytes (Mono, eosinophils (Eosin and basophils (Baso were similar among the four treatment groups, while serum levels of Se and I increased significantly (p<0.05 in the supplemented groups. The combined dietary supplementation of Se and I (SSPI significantly increased serum FT3 in the supplemented animals. Serum GSH-Px activity increased significantly in the animals of SS and SSPI groups. It is concluded that the dietary supplementation of inorganic Se and I at a level of 0.6 mg/kg DM increased serum Se and I concentration, FT3 hormone and GSH-Px activity of Kacang crossbred male goats.

  13. Glutathione peroxidase 4 overexpression inhibits ROS-induced cell death in diffuse large B-cell lymphoma.

    Science.gov (United States)

    Kinowaki, Yuko; Kurata, Morito; Ishibashi, Sachiko; Ikeda, Masumi; Tatsuzawa, Anna; Yamamoto, Masahide; Miura, Osamu; Kitagawa, Masanobu; Yamamoto, Kouhei

    2018-02-20

    Regulation of oxidative stress and redox systems has important roles in carcinogenesis and cancer progression, and for this reason has attracted much attention as a new area of cancer therapeutic targets. Glutathione peroxidase 4 (GPX4), an antioxidant enzyme, has biological important functions such as signaling cell death by suppressing peroxidation of membrane phospholipids. However, few studies exist on the expression and clinical relevance of GPX4 in malignant lymphomas such as diffuse large B-cell lymphoma. In this study, we assessed the expression of GPX4 immunohistochemically. GPX4 was expressed in 35.5% (33/93) cases of diffuse large B-cell lymphoma. The GPX4-positive group had poor overall survival (P = 0.0032) and progression-free survival (P = 0.0004) compared with those of the GPX4-negative group. In a combined analysis of GPX4 and 8-hydroxydeoxyguanosine (8-OHdG), an oxidative stress marker, there was a negative correlation between GPX4 and 8-hydroxydeoxyguanosine (P = 0.0009). The GPX4-positive and 8-hydroxydeoxyguanosine-negative groups had a significantly worse prognosis than the other groups in both overall survival (P = 0.0170) and progression-free survival (P = 0.0005). These results suggest that the overexpression of GPX4 is an independent prognostic predictor in diffuse large B-cell lymphoma. Furthermore, in vitro analysis demonstrated that GPX4-overexpressing cells were resistant to reactive oxygen species-induced cell death (P = 0.0360). Conversely, GPX4-knockdown cells were sensitive to reactive oxygen species-induced cell death (P = 0.0111). From these data, we conclude that GPX4 regulates reactive oxygen species-induced cell death. Our results suggest a novel therapeutic strategy using the mechanism of ferroptosis, as well as a novel prognostic predictor of diffuse large B-cell lymphoma.

  14. Elevated expression of glutathione peroxidase in PC12 cells results in protection against methamphetamine but not MPTP toxicity.

    Science.gov (United States)

    Hom, D G; Jiang, D; Hong, E J; Mo, J Q; Andersen, J K

    1997-06-01

    In vivo administration of either 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) or methamphetamine (MA) produces damage to the dopaminergic nervous system which may be due in part to the generation of reactive oxygen species (ROS). The resistance of superoxide dismutase (SOD) over-expressing transgenic mice to the effects of both MPTP and MA suggests the involvement of superoxide in the resulting neurotoxicity of both compounds. Superoxide can be converted by SOD to hydrogen peroxide, which itself can cause cellular degeneration by reacting with free iron to produce highly reactive hydroxyl radicals resulting in damage to proteins, nucleic acids and membrane phospholipids. Hydrogen peroxide has also been reported to be produced via inhibition of NADH dehydrogenase by MPP + formed during oxidation of MPTP by MAO-B and by dopamine auto-oxidation following MA-induced dopamine release from synaptic vesicles within nerve terminals. To test whether hydrogen peroxide is an important factor in the toxicity of either of these two neurotoxins, we created clonal PC12 lines expressing elevated levels of the hydrogen peroxide-reducing enzyme glutathione peroxidase (GSHPx). Elevation of GSHPx levels in PC12 was found to diminish the rise in ROS levels and lipid peroxidation resulting from MA but not MPTP treatment. Elevated levels of GSHPx also appeared to prevent decreases in transport-mediated dopamine uptake produced via MA administration as well as to attenuate toxin-induced cell loss as measured by either MTT reduction or LDH release. Our data, therefore, suggest that hydrogen peroxide production likely contributes to MA toxicity in dopaminergic neurons.

  15. A selenium-deficient Caco-2 cell model for assessing differential incorporation of chemical or food selenium into glutathione peroxidase.

    Science.gov (United States)

    Zeng, Huawei; Botnen, James H; Johnson, Luann K

    2008-01-01

    Assessing the ability of a selenium (Se) sample to induce cellular glutathione peroxidase (GPx) activity in Se-deficient animals is the most commonly used method to determine Se bioavailability. Our goal is to establish a Se-deficient cell culture model with differential incorporation of Se chemical forms into GPx, which may complement the in vivo studies. In the present study, we developed a Se-deficient Caco-2 cell model with a serum gradual reduction method. It is well recognized that selenomethionine (SeMet) is the major nutritional source of Se; therefore, SeMet, selenite, or methylselenocysteine (SeMSC) was added to cell culture media with different concentrations and treatment time points. We found that selenite and SeMSC induced GPx more rapidly than SeMet. However, SeMet was better retained as it is incorporated into proteins in place of methionine; compared with 8-, 24-, or 48-h treatment, 72-h Se treatment was a more sensitive time point to measure the potential of GPx induction in all tested concentrations. Based on induction of GPx activity, the cellular bioavailability of Se from an extract of selenobroccoli after a simulated gastrointestinal digestion was comparable with that of SeMSC and SeMet. These in vitro data are, for the first time, consistent with previous published data regarding selenite and SeMet bioavailability in animal models and Se chemical speciation studies with broccoli. Thus, Se-deficient Caco-2 cell model with differential incorporation of chemical or food forms of Se into GPx provides a new tool to study the cellular mechanisms of Se bioavailability.

  16. Gene architecture and expression analyses provide insights into the role of glutathione peroxidases (GPXs) in bread wheat (Triticum aestivum L.).

    Science.gov (United States)

    Tyagi, Shivi; Himani; Sembi, Jaspreet K; Upadhyay, Santosh Kumar

    2018-04-01

    Glutathione peroxidases (GPXs) are redox sensor proteins that maintain a steady-state of H 2 O 2 in plant cells. They exhibit distinct sub-cellular localization and have diverse functionality in response to different stimuli. In this study, a total of 14 TaGPX genes and three splice variants were identified in the genome of Triticum aestivum and evaluated for various physicochemical properties. The TaGPX genes were scattered on the various chromosomes of the A, B, and D sub-genomes and clustered into five homeologous groups based on high sequence homology. The majority of genes were derived from the B sub-genome and localized on chromosome 2. The intron-exon organization, motif and domain architecture, and phylogenetic analyses revealed the conserved nature of TaGPXs. The occurrence of both development-related and stress-responsive cis-acting elements in the promoter region, the differential expression of these genes during various developmental stages, and the modulation of expression in the presence of biotic and abiotic stresses suggested their diverse role in T. aestivum. The majority of TaGPX genes showed higher expression in various leaf developmental stages. However, TaGPX1-A1 was upregulated in the presence of each abiotic stress treatment. A co-expression analysis revealed the interaction of TaGPXs with numerous development and stress-related genes, which indicated their vital role in numerous biological processes. Our study revealed the opportunities for further characterization of individual TaGPX proteins, which might be useful in designing future crop improvement strategies. Copyright © 2018 Elsevier GmbH. All rights reserved.

  17. Synthesis, structure, and glutathione peroxidase-like activity of amino acid containing ebselen analogues and diaryl diselenides.

    Science.gov (United States)

    Selvakumar, Karuthapandi; Shah, Poonam; Singh, Harkesh B; Butcher, Ray J

    2011-11-04

    The synthesis of some ebselen analogues and diaryl diselenides, which have amino acid functions as an intramolecularly coordinating group (Se···O) has been achieved by the DCC coupling procedure. The reaction of 2,2'-diselanediylbis(5-tert-butylisophthalic acid) or the activated ester tetrakis(2,5-dioxopyrrolidin-1-yl) 2,2'-diselanediylbis(5-tert-butylisophthalate) with different C-protected amino acids (Gly, L-Phe, L-Ala, and L-Trp) afforded the corresponding ebselen analogues. The used precursor diselenides have been found to undergo facile intramolecular cyclization during the amide bond formation reaction. In contrast, the DCC coupling of 2,2'-diselanediyldibenzoic acid with C-protected amino acids (Gly, L/D-Ala and L-Phe) affords the corresponding amide derivatives and not the ebselen analogues. Some of the representative compounds have been structurally characterized by single-crystal X-ray crystallography. The glutathione peroxidase (GPx)-like activities of the ebselen analogues and the diaryl diselenides have been evaluated by using the coupled reductase assay method. Intramolecularly stabilized ebselen analogues show slightly higher maximal velocity (V(max)) than ebselen. However, they do not show any GPx-like activity at low GSH concentrations at which ebselen and related diselenides are active. This could be attributed to the peroxide-mediated intramolecular cyclization of the corresponding selenenyl sulfide and diaryl diselenide intermediates generated during the catalytic cycle. Interestingly, the diaryl diselenides with alanine (L,L or D,D) amide moieties showed excellent catalytic efficiency (k(cat)/K(M)) with low K(M) values in comparison to the other compounds. Copyright © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  18. Glutathione peroxidase-1 gene (GPX1) variants, oxidative stress and risk of kidney complications in people with type 1 diabetes.

    Science.gov (United States)

    Mohammedi, Kamel; Patente, Thiago A; Bellili-Muñoz, Naima; Driss, Fathi; Le Nagard, Hervé; Fumeron, Frédéric; Roussel, Ronan; Hadjadj, Samy; Corrêa-Giannella, Maria Lúcia; Marre, Michel; Velho, Gilberto

    2016-02-01

    Glutathione peroxidase (GPX) is a class of antioxidant enzymes that catalyze the reduction of hydrogen peroxide to water. GPX1 is the most abundant isoform and is expressed in all kidney cells. Isoprostane and advanced oxidation protein products (AOPP) were identified as markers of oxidative stress in patients with kidney disease. We investigated associations of GPX1 genotypes with kidney complications, and with plasma concentrations of isoprostane and AOPP in type 1 diabetic patients. Four SNPs in the GPX1 gene region were genotyped in SURGENE (n=340; 10-year follow-up); GENEDIAB (n=461) and GENESIS (n=584) cohorts of type 1 diabetic patients. Subsets of GENEDIAB (n=237) and GENESIS (n=466) participants were followed up for 9 and 5years, respectively. Plasma concentrations of isoprostane and AOPP were measured at baseline in GENEDIAB. Hazard ratios (HR) were estimated for incidence of kidney complications. In SURGENE, 98 renal events (new cases of microalbuminuria or progression to more severe stage of diabetic nephropathy) occurred during follow-up. The minor T-allele of rs3448 was associated with the incidence of renal events (HR 1.81, 95% CI 1.16-2.84, p=0.008). In GENESIS/GENEDIAB pooled study, end stage renal disease (ESRD) occurred during follow-up in 52 individuals. The same variant was associated with the incidence of ESRD (HR 3.34, 95% CI, 1.69-6.98, p=0.0004). The variant was also associated with higher plasma isoprostane concentration in GENEDIAB cohort: 2.02±0.12 (TT+CT) vs 1.75±0.13 (CC) ng/mL (p=0.009), and with higher plasma AOPP in the subset of participants with the baseline history of ESRD (TT+CT 67±6 vs CC 48±6μmol/L, p=0.006). The minor T-allele of rs3448 was associated with kidney complications (incidences of microalbuminuria, renal events and ESRD) in patients with type 1 diabetes. The risk allele was associated with higher plasma concentrations of isoprostane and AOPP. Our results are consistent with the implication of GPX1 in the

  19. Probucol increases striatal glutathione peroxidase activity and protects against 3-nitropropionic acid-induced pro-oxidative damage in rats.

    Directory of Open Access Journals (Sweden)

    Dirleise Colle

    Full Text Available Huntington's disease (HD is an autosomal dominantly inherited neurodegenerative disease characterized by symptoms attributable to the death of striatal and cortical neurons. The molecular mechanisms mediating neuronal death in HD involve oxidative stress and mitochondrial dysfunction. Administration of 3-nitropropionic acid (3-NP, an irreversible inhibitor of the mitochondrial enzyme succinate dehydrogenase, in rodents has been proposed as a useful experimental model of HD. This study evaluated the effects of probucol, a lipid-lowering agent with anti-inflammatory and antioxidant properties, on the biochemical parameters related to oxidative stress, as well as on the behavioral parameters related to motor function in an in vivo HD model based on 3-NP intoxication in rats. Animals were treated with 3.5 mg/kg of probucol in drinking water daily for 2 months and, subsequently, received 3-NP (25 mg/kg i.p. once a day for 6 days. At the end of the treatments, 3-NP-treated animals showed a significant decrease in body weight, which corresponded with impairment on motor ability, inhibition of mitochondrial complex II activity and oxidative stress in the striatum. Probucol, which did not rescue complex II inhibition, protected against behavioral and striatal biochemical changes induced by 3-NP, attenuating 3-NP-induced motor impairments and striatal oxidative stress. Importantly, probucol was able to increase activity of glutathione peroxidase (GPx, an enzyme important in mediating the detoxification of peroxides in the central nervous system. The major finding of this study was that probucol protected against 3-NP-induced behavioral and striatal biochemical changes without affecting 3-NP-induced mitochondrial complex II inhibition, indicating that long-term probucol treatment resulted in an increased resistance against neurotoxic events (i.e., increased oxidative damage secondary to mitochondrial dysfunction. These data appeared to be of great

  20. Redox regulation of antioxidant enzymes: post-translational modulation of catalase and glutathione peroxidase activity by resveratrol in diabetic rat liver.

    Science.gov (United States)

    Sadi, Gökhan; Bozan, Davut; Yildiz, Huseyin Bekir

    2014-08-01

    Resveratrol is a strong antioxidant that exhibits blood glucose-lowering effects, which might contribute to its usefulness in preventing complications associated with diabetes. The present study aimed to investigate resveratrol effects on catalase (CAT) and glutathione peroxidase (GPx) gene and protein expression, their phosphorylation states and activities in rat liver of STZ-induced diabetes. Diabetes increased the levels of total protein phosphorylation and p-CAT, while mRNA expression, protein levels, and activity were reduced. Although diabetes induced transcriptional repression over GPx, it did not affect the protein levels and activity. When resveratrol was administered to diabetic rats, an increase in activity was associated with an increase in p-GPx levels. Decrease in Sirtuin1 (SIRT1) and nuclear factor erythroid 2-related factor (Nrf2) and increase in nuclear factor kappa B (NFκB) gene expression in diabetes were associated with a decrease in CAT and GPx mRNA expression. A possible compensatory mechanism for reduced gene expression of antioxidant enzymes is proved to be nuclear translocation of redox-sensitive Nrf2 and NFκB in diabetes which is confirmed by the increase in nuclear and decrease in cytoplasmic protein levels of Nrf2 and NFκB. Taken together, these findings revealed that an increase in the oxidized state in diabetes intricately modified the cellular phosphorylation status and regulation of antioxidant enzymes. Gene regulation of antioxidant enzymes was accompanied by nuclear translocation of Nrf2 and NFκB. Resveratrol administration also activated a coordinated cytoprotective response against diabetes-induced changes in liver tissues.

  1. Dietary fish oil replacement with palm or poultry oil increases fillet oxidative stability and decreases liver glutathione peroxidase activity in barramundi (Lates calcarifer).

    Science.gov (United States)

    Wan Ahmad, Wan A R; Stone, David A J; Schuller, Kathryn A

    2013-12-01

    Complete dietary fish oil replacement with palm or poultry oil in barramundi (Lates calcarifer) had no detrimental effects on growth or hepatosomatic index of juvenile fish up to an average size of ~50 g. However, it significantly decreased the omega-3 (n-3) long-chain polyunsaturated fatty acid content of the fish muscle (fillet) lipids. This was particularly true for eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) which are recognised for their health beneficial effects in the human diet. As a result of their decreased EPA and DHA content, the peroxidation index of the muscle lipids was also decreased. This was associated with increased simulated retail storage shelf life as indicated by decreased thiobarbituric acid reactive substances in muscle samples from fish fed the palm or poultry oil-based diets. Concomitantly, glutathione peroxidase (GPx) activity, but not glutathione S-transferase (GST) activity or reduced glutathione concentration, was significantly reduced in the liver of barramundi fed the palm or poultry oil-based diets as compared with the fish fed the fish oil-based diet. Furthermore, GPx and GST activity were very low in muscle, much lower than in gastrointestinal tract, liver or swim bladder. Therefore, we propose that liver GPx activity may be a good predictor of fillet shelf life in barramundi and other fish species.

  2. Effect of vitamin E (DL-all-rac-a-tocopherol acetate and nano particles of selenium on growth, survival, body composition and whole body glutathione peroxidase (GPX and malondialdehyde (MDA in Rutilus kutum (Kamensky, 1901

    Directory of Open Access Journals (Sweden)

    Tahmasbi Davoud

    2017-06-01

    Full Text Available The effect of vitamin E (100 mg kg−1 and nano-selenium (1 mg kg−1, which have a nutritional relationship separately and in combination, was investigated on growth, survival, carcass composition, body glutathione peroxidase activity, and body malondialdehyde content of Rutilus kutum. Results showed that vitamin E is capable of improving growth, FCR and WG in Kutum fingerlings; however, nano-selenium is not. According to this study, vitamin E can improve growth and selenium can improve glutathione peroxidase activity in Rutilus kutum larvae.

  3. Effects of reduced glutathion and vitamin c on cisplatin-induced ...

    African Journals Online (AJOL)

    glutathione peroxidase [GSHPx], catalase [CAT], glutathione reductase [GSHR] activities and gene expression, glutathione [GSH] content) and lipid peroxidation products (malondialdehyde, MDA) in rat liver tissue were measured. CDDP hepatotoxicity was manifested by an increase in serum ALT and AST, elevation of MDA ...

  4. Two wheat glutathione peroxidase genes whose products are located in chloroplasts improve salt and H2O2 tolerances in Arabidopsis.

    Directory of Open Access Journals (Sweden)

    Chao-Zeng Zhai

    Full Text Available Oxidative stress caused by accumulation of reactive oxygen species (ROS is capable of damaging effects on numerous cellular components. Glutathione peroxidases (GPXs, EC 1.11.1.9 are key enzymes of the antioxidant network in plants. In this study, W69 and W106, two putative GPX genes, were obtained by de novo transcriptome sequencing of salt-treated wheat (Triticum aestivum seedlings. The purified His-tag fusion proteins of W69 and W106 reduced H2O2 and t-butyl hydroperoxide (t-BHP using glutathione (GSH or thioredoxin (Trx as an electron donor in vitro, showing their peroxidase activity toward H2O2 and toxic organic hydroperoxide. GFP fluorescence assays revealed that W69 and W106 are localized in chloroplasts. Quantitative real-time PCR (Q-RT-PCR analysis showed that two GPXs were differentially responsive to salt, drought, H2O2, or ABA. Isolation of the W69 and W106 promoters revealed some cis-acting elements responding to abiotic stresses. Overexpression of W69 and W106 conferred strong tolerance to salt, H2O2, and ABA treatment in Arabidopsis. Moreover, the expression levels of key regulator genes (SOS1, RbohD and ABI1/ABI2 involved in salt, H2O2 and ABA signaling were altered in the transgenic plants. These findings suggest that W69 and W106 not only act as scavengers of H2O2 in controlling abiotic stress responses, but also play important roles in salt and ABA signaling.

  5. Variation in risk indicators of cardiovascular disease during the menstrual cycle: an investigation of within-subject variations in glutathione peroxidase, haemostatic variables, lipids and lipoproteins in healthy young women

    DEFF Research Database (Denmark)

    Larsen, L F; Andersen, H R; Hansen, A B

    1996-01-01

    Variations in erythrocyte glutathione peroxidase activity, serum concentrations of lipids and lipoproteins and in blood coagulation and fibrinolysis during the menstrual cycle were studied in healthy young women. Blood samples were drawn twice a week for 9 weeks. A group of males was used...

  6. Glutathione protects liver and kidney tissue from cadmium- and lead-provoked lipid peroxidation

    Directory of Open Access Journals (Sweden)

    Jovanović Jasmina M.

    2013-01-01

    Full Text Available Cd and Pb represent a serious ecological problem due to their soluble nature, their mobility and ability to accumulate in the soil. The exposure to these heavy metals can originate from different sources (drinking water, food, air, and they can make their way into the human body through the respiratory and digestive system. We investigated the effects of glutathione on Cd and Pb accumulation and lipid peroxidation effects in the liver and kidneys of heavy metal intoxicated rats. The content of the marker of lipid peroxidation - malondialdehyde was increased several fold the in tissues of exposed animals, the effects being more pronounced in liver. The treatment of intoxicated animals with glutathione drastically suppressed lipid peroxidation. Our results imply that the application of glutathione may have protective role in heavy metal intoxication by inhibiting lipid peroxidation. However, precaution should be made when it comes to Cd, since it seems that glutathione promoted Cd accumulation in the liver.

  7. Peroxidase-mediated binding of aromatic amine carcinogens to tissue DNA

    International Nuclear Information System (INIS)

    Wise, R.W.; Lakshmi, V.M.; Zenser, T.V.; Davis, B.B.

    1986-01-01

    Benzidine is a aromatic amine bladder carcinogen in man and dog which requires endogenous metabolic activation. Dog bladder microsomes activate benzidine to bind glutathione and DNA by a peroxidatic but not a mixed-function oxidase mediated pathway. Prostaglandin H synthase was responsible for peroxidatic metabolism. This study was designed to assess benzidine metabolism in a whole cell system. Rabbit renal medullary slices (100 mg/ml) were incubated for 60 min. in Krebs-Ringer bicarbonate buffer containing 100 μM 3 H-benzidine and 250 μM arachidonic acid. Arachidonic acid increased 3-(glutathione-S-yL)-benzidine, a product of peroxidatically activated benzidine, (6-fold) and 3 H-benzidine binding to endogenous DNA (4-fold). Indomethacin (100 μM) completely inhibited arachidonic acid-mediated increases in conjugate formation and DNA binding. HPLC analysis of the media demonstrated benzidine (95% of total 3 H), 3-(glutathion-S-yL)-benzidine (1%) and two unidentified peaks (4%). These results are consistent with the hydroperoxidase activity of prostaglandin H synthase mediating metabolic activation of benzidine to bind tissue nucleophiles in a whole cell system. Inhibition of peroxidatic activation of aromatic amines to bind DNA may prevent initiation of bladder cancer

  8. Docosahexaenoic (DHA modulates phospholipid-hydroperoxide glutathione peroxidase (Gpx4 gene expression to ensure self-protection from oxidative damage in hippocampal cells

    Directory of Open Access Journals (Sweden)

    Veronica eCasañas-Sanchez

    2015-07-01

    Full Text Available Docosahexaenoic acid (DHA, 22:6n-3 is a unique polyunsaturated fatty acid particularly abundant in nerve cell membrane phospholipids. DHA is a pleiotropic molecule that, not only modulates the physicochemical properties and architecture of neuronal plasma membrane, but it is also involved in multiple facets of neuronal biology, from regulation of synaptic function to neuroprotection and modulation of gene expression. As a highly unsaturated fatty acid due to the presence of six double bonds, DHA is susceptible for oxidation, especially in the highly pro-oxidant environment of brain parenchyma. We have recently reported the ability of DHA to regulate the transcriptional program controlling neuronal antioxidant defenses in a hippocampal cell line, especially the glutathione/glutaredoxin system. Within this antioxidant system, DHA was particularly efficient in triggering the upregulation of Gpx4 gene, which encodes for the nuclear, cytosolic and mitochondrial isoforms of phospholipid-hydroperoxide glutathione peroxidase (PH-GPx/GPx4, the main enzyme protecting cell membranes against lipid peroxidation and capable to reduce oxidized phospholipids in situ. We show here that this novel property of DHA is also significant in the hippocampus of wild-type mice and APP/PS1 transgenic mice, a familial model of Alzheimer’s disease. By doing this, DHA stimulates a mechanism to self-protect from oxidative damage even in the neuronal scenario of high aerobic metabolism and in the presence of elevated levels of transition metals, which inevitably favor the generation of reactive oxygen species. Noticeably, DHA also upregulated a novel Gpx4 splicing variant, harboring part of the first intronic region, which according to the ‘sentinel RNA hypothesis’ would expand the ability of Gpx4 (and DHA to provide neuronal antioxidant defense independently of conventional nuclear splicing in cellular compartments, like dendritic zones, located away from nuclear

  9. The Effect of Fasting on the Concentration of Enzimatic Antioxidants (Superoxide Dismutase and Glutathione Peroxidase in Rats

    Directory of Open Access Journals (Sweden)

    Muliatul Jannah

    2016-06-01

    Full Text Available Introduction: Consumption of excessive calories can increase the incidence of degenerative diseases mediated by ROS. Caloric restriction, have been shown to increase levels of antioxidants superoxide dismutase (SOD and Gluthatione Peroxidase (GPx. Fasting like Ramadan fasting (FLRF is a form of calorie restriction, but its effect on levels of SOD and GPx remains unclear. Objectives: to investigate the effect of fasting on levels of SOD and GPx. Methods: in a post-test only control group design, sample of 24 rats Sprague Dawley Rats aged 3-month-old, weighing 250-300 grams, were randomly divided into 4 groups. Group 1 (P-70, 2 (P-100, and 3 (P-140 were fasted for 6 hours/day, each group received of 70%, 100% and 140% calories respectively. Group 4 (C-AL received 100% calories, ad libitum. Day 16 blood was taken and levels of SOD and GPx were determined by ELISA. Data were analyzed using one-way ANOVAs, followed by post hoc LSD tests, p<0.05 was considered statistically significant. Results: the results showed that the levels of SOD and GPx occur significant differences between the groups, p = 0.000. The test results post hoc SOD (318.64 and GPx (89.16 group P-70, compared with group C-AL (278.60 and 57.20 was significantly higher (p = 0.00. SOD and GPx P-70 group compared with the group P-140 (92.03 and 48.79, significantly higher (p = 0.00. Compared with group P-100 (296.70 and 75.71 SOD and GPx in group P-70 was significantly higher, p = 0.000. Conclusion: Fasting with calorie intake of 70% and 100% for 15 days can increases levels of SOD and GPx in male rats.

  10. Nucleotide diversity and gene expression of Catalase and Glutathione peroxidase in irradiated Scots pine (Pinus sylvestris L.) from the Chernobyl exclusion zone

    International Nuclear Information System (INIS)

    Vornam, Barbara; Arkhipov, Andrey; Finkeldey, Reiner

    2012-01-01

    In the Chernobyl exclusion zone forest trees have to tolerate and to adapt to ionizing radiation, therefore the molecular basis of their adaptive responses is of the utmost interest. Based on SNP analysis and real time PCR nucleotide diversity and expression profiles of gene fragments of catalase (Cat) and glutathione peroxidase (GPx), which are known as radical scavenging genes, were analysed in the needles of irradiated pine trees of the Chernobyl exclusion zone. In acutely and chronically irradiated trees (50 years old) planted before the accident a higher nucleotide diversity of Cat and more somatic mutations were found compared to their control. Chronically irradiated trees (20 years old) planted after the accident showed a similar nucleotide diversity of Cat compared to their control and in both collectives one somatic mutation was found. The nucleotide diversity of GPx was higher in all analysed trees compared to Cat. No somatic mutation events were found in GPx. For both gene fragments, no association between the received dose in a tree and the nucleotide diversity and mutation events was detected. The expression profiles of Cat and GPx in acutely and chronically and in chronically irradiated trees were similar. Compared to their corresponding control collectives, Cat was up-regulated and GPx slightly down-regulated.

  11. Dietary Selenium Deficiency or Excess Reduces Sperm Quality and Testicular mRNA Abundance of Nuclear Glutathione Peroxidase 4 in Rats.

    Science.gov (United States)

    Zhou, Ji-Chang; Zheng, Shijie; Mo, Junluan; Liang, Xiongshun; Xu, Yuanfei; Zhang, Huimin; Gong, Chunmei; Liu, Xiao-Li; Lei, Xin Gen

    2017-10-01

    Background: Glutathione peroxidase (GPX) 4 and selenoprotein P (SELENOP) are abundant, and several variants are expressed in the testis. Objective: We determined the effects of dietary selenium deficiency or excess on sperm quality and expressions of GPX4 and SELENOP variants in rat testis and liver. Methods: After weaning, male Sprague-Dawley rats were fed a Se-deficient basal diet (BD) for 5 wk until they were 9 wk old [mean ± SEM body weight (BW) = 256 ± 5 g]. They were then fed the BD diet alone (deficient) or with 0.25 (adequate), 3 (excess), or 5 (excess) mg Se/kg for 4 wk. Testis, liver, blood, and semen were collected to assay for selenoprotein mRNA and protein abundances, selenium concentration, GPX activity, 8-hydroxy-deoxyguanosine concentration, and sperm quality. Results: Dietary selenium supplementations elevated ( P selenium concentrations and GPX activities. Compared with those fed BD + 0.25 mg Se/kg, rats fed BD showed lower ( P selenium-adequate group. Compared with the selenium-adequate group, dietary selenium deficiency (BD) or excess (BD + 3 or 5 mg Se/kg) resulted in 45-77% lower ( P selenium concentrations in similar ways to sperm parameters and may be used as a sensitive marker to assess appropriate Se status for male function. © 2017 American Society for Nutrition.

  12. Mice Deficient in Both Mn Superoxide Dismutase and Glutathione Peroxidase-1 Have Increased Oxidative Damage and a Greater Incidence of Pathology but No Reduction in Longevity

    Science.gov (United States)

    Zhang, Yiqiang; Ikeno, Yuji; Qi, Wenbo; Chaudhuri, Asish; Li, Yan; Bokov, Alex; Thorpe, Suzanne R.; Baynes, John W.; Epstein, Charles; Richardson, Arlan

    2009-01-01

    To test the impact of increased mitochondrial oxidative stress as a mechanism underlying aging and age-related pathologies, we generated mice with a combined deficiency in two mitochondrial-localized antioxidant enzymes, Mn superoxide dismutase (MnSOD) and glutathione peroxidase-1 (Gpx-1). We compared life span, pathology, and oxidative damage in Gpx1−/−, Sod2+/−Gpx1+/−, Sod2+/−Gpx1−/−, and wild-type control mice. Oxidative damage was elevated in Sod2+/−Gpx1−/− mice, as shown by increased DNA oxidation in liver and skeletal muscle and increased protein oxidation in brain. Surprisingly, Sod2+/−Gpx1−/− mice showed no reduction in life span, despite increased levels of oxidative damage. Consistent with the important role for oxidative stress in tumorigenesis during aging, the incidence of neoplasms was significantly increased in the older Sod2+/−Gpx1−/− mice (28–30 months). Thus, these data do not support a significant role for increased oxidative stress as a result of compromised mitochondrial antioxidant defenses in modulating life span in mice and do not support the oxidative stress theory of aging. PMID:19776219

  13. The effect of alcohol and hydrogen peroxide on liver hepcidin gene expression in mice lacking antioxidant enzymes, glutathione peroxidase-1 or catalase.

    Science.gov (United States)

    Harrison-Findik, Duygu Dee; Lu, Sizhao

    2015-05-06

    This study investigates the regulation of hepcidin, the key iron-regulatory molecule, by alcohol and hydrogen peroxide (H2O2) in glutathione peroxidase-1 (gpx-1(-/-)) and catalase (catalase(-/-)) knockout mice. For alcohol studies, 10% ethanol was administered in the drinking water for 7 days. Gpx-1(-/-) displayed significantly higher hepatic H2O2 levels than catalase(-/-) compared to wild-type mice, as measured by 2'-7'-dichlorodihydrofluorescein diacetate (DCFH-DA). The basal level of liver hepcidin expression was attenuated in gpx-1(-/-) mice. Alcohol increased H2O2 production in catalase(-/-) and wild-type, but not gpx-1(-/-), mice. Hepcidin expression was inhibited in alcohol-fed catalase(-/-) and wild-type mice. In contrast, alcohol elevated hepcidin expression in gpx-1(-/-) mice. Gpx-1(-/-) mice also displayed higher level of basal liver CHOP protein expression than catalase(-/-) mice. Alcohol induced CHOP and to a lesser extent GRP78/BiP expression, but not XBP1 splicing or binding of CREBH to hepcidin gene promoter, in gpx-1(-/-) mice. The up-regulation of hepatic ATF4 mRNA levels, which was observed in gpx-1(-/-) mice, was attenuated by alcohol. In conclusion, our findings strongly suggest that H2O2 inhibits hepcidin expression in vivo. Synergistic induction of CHOP by alcohol and H2O2, in the absence of gpx-1, stimulates liver hepcidin gene expression by ER stress independent of CREBH.

  14. High-Resolution Imaging of Selenium in Kidneys: A Localized Selenium Pool Associated with Glutathione Peroxidase 3

    OpenAIRE

    Malinouski, Mikalai; Kehr, Sebastian; Finney, Lydia; Vogt, Stefan; Carlson, Bradley A.; Seravalli, Javier; Jin, Richard; Handy, Diane E.; Park, Thomas J.; Loscalzo, Joseph; Hatfield, Dolph L.; Gladyshev, Vadim N.

    2012-01-01

    Aim: Recent advances in quantitative methods and sensitive imaging techniques of trace elements provide opportunities to uncover and explain their biological roles. In particular, the distribution of selenium in tissues and cells under both physiological and pathological conditions remains unknown. In this work, we applied high-resolution synchrotron X-ray fluorescence microscopy (XFM) to map selenium distribution in mouse liver and kidney. Results: Liver showed a uniform selenium distributio...

  15. Effect of cystamine on rat tissue GSH level and glutathione reductase activity

    International Nuclear Information System (INIS)

    Kovarova, H.; Pulpanova, J.

    1979-01-01

    Reduced glutathione (GSH) level and glutathione reductase activity were determined by means of the spectrophotometric method in various rat tissues after i.p. administration of cystamine (50 mg/kg and 20 mg/kg). GSH amount dropped in the spleen and kidney at 10 and 20 min; following this interval, an increase of GSH level was observed in the liver at 20-30 min, in the spleen and kidney at 60 min after the treatment with a radioprotective cystamine dose (50 mg/kg). The changes in GSH level induced by a non-radioprotective cystamine dose (20 mg/kg) had an opposite tendency. The activity of glutathione reductase was decreased in all tissues studied. As to the mechanism of the radioprotective action, both the inactivation of glutathione reductase activity and the changes in GSH level seem to be the factors contributing to the radioprotective effect of cystamine by strengthening the cellular radioresistance. (orig.) 891 MG/orig. 892 RKD [de

  16. Superoxide dismutase, catalase, glutathione peroxidase and gluthatione S-transferases M1 and T1 gene polymorphisms in three Brazilian population groups.

    Science.gov (United States)

    de Oliveira Hiragi, Cássia; Miranda-Vilela, Ana Luisa; Rocha, Dulce Maria Sucena; de Oliveira, Silviene Fabiana; Hatagima, Ana; de Nazaré Klautau-Guimarães, Maria

    2011-01-01

    Antioxidants such as superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GPX1) reduce the oxidation rates in the organism. Gluthatione S-transferases (GSTs) play a vital role in phase 2 of biotransformation of many substances. Variation in the expression of these enzymes suggests individual differences for the degree of antioxidant protection and geographical differences in the distribution of these variants. We described the distribution frequency of CAT (21A/T), SOD2 (Ala9Val), GPX1 (Pro198Leu), GSTM1 and GSTT1 polymorphisms in three Brazilian population groups: Kayabi Amerindians (n = 60), Kalunga Afro-descendants (n = 72), and an urban mixed population from Federal District (n = 162). Frequencies of the variants observed in Kalunga (18% to 58%) and Federal District (33% to 63%) were similar to those observed in Euro and Afro-descendants, while in Kayabi (3% to 68%), depending on the marker, frequencies were similar to the ones found in different ethnic groups. Except for SOD2 in all population groups studied here, and for GPX1 in Kalunga, the genotypic distributions were in accordance with Hardy-Weinberg Equilibrium. These data can clarify the contribution of different ethnicities in the formation of mixed populations, such as that of Brazil. Moreover, outcomes will be valuable resources for future functional studies and for genetic studies in specific populations. If these studies are designed to comprehensively explore the role of these genetic polymorphisms in the etiology of human diseases they may help to prevent inconsistent genotype-phenotype associations in pharmacogenetic studies.

  17. Genetic association of glutathione peroxidase-1 with coronary artery calcification in type 2 diabetes: a case control study with multi-slice computed tomography

    Directory of Open Access Journals (Sweden)

    Fujimoto Kei

    2007-09-01

    Full Text Available Abstract Background Although oxidative stress by accumulation of reactive oxygen species (ROS in diabetes has become evident, it remains unclear what genes, involved in redox balance, would determine susceptibility for development of atherosclerosis in diabetes. This study evaluated the effect of genetic polymorphism of enzymes producing or responsible for reducing ROS on coronary artery calcification in type 2 diabetes (T2D. Methods An index for coronary-arteriosclerosis, coronary artery calcium score (CACS was evaluated in 91 T2D patients using a multi-slice computed tomography. Patients were genotyped for ROS-scavenging enzymes, Glutathione peroxidase-1 (GPx-1, Catalase, Mn-SOD, Cu/Zn-SOD, as well as SNPs of NADPH oxidase as ROS-promoting elements, genes related to onset of T2D (CAPN10, ADRB3, PPAR gamma, FATP4. Age, blood pressure, BMI, HbA1c, lipid and duration of diabetes were evaluated for a multivariate regression analysis. Results CACS with Pro/Leu genotype of the GPx-1 gene was significantly higher than in those with Pro/Pro (744 ± 1,291 vs. 245 ± 399, respectively, p = 0.006. In addition, genotype frequency of Pro/Leu in those with CACS ≥ 1000 was significantly higher than in those with CACS OR = 3.61, CI = 0.97–13.42; p = 0.045 when tested for deviation from Hardy-Weinberg's equilibrium. Multivariate regression analyses revealed that CACS significantly correlated with GPx-1 genotypes and age. Conclusion The presence of Pro197Leu substitution of the GPx-1 gene may play a crucial role in determining genetic susceptibility to coronary-arteriosclerosis in T2D. The mechanism may be associated with a decreased ability to scavenge ROS with the variant GPx-1.

  18. Daily rhythms of catalase and glutathione peroxidase expression and activity are endogenously driven in the hippocampus and are modified by a vitamin A-free diet.

    Science.gov (United States)

    Navigatore-Fonzo, Lorena S; Delgado, Silvia M; Gimenez, Maria Sofia; Anzulovich, Ana C

    2014-01-01

    Alterations in enzymatic antioxidant defense systems lead to a deficit of cognitive functions and altered hippocampal synaptic plasticity. The objectives of this study were to investigate endogenous rhythms of catalase (CAT) and glutathione peroxidase (GPx) expression and activity, as well as CREB1 mRNA, in the rat hippocampus, and to evaluate to which extent the vitamin A deficiency could affect those temporal patterns. Rats from control and vitamin A-deficient (VAD) groups received a diet containing 4000 IU of vitamin A/kg diet, or the same diet devoid of vitamin A, respectively, during 3 months. Rats were maintained under 12-hour-dark conditions, during 10 days before the sacrifice. Circadian rhythms of CAT, GPx, RXRγ, and CREB1 mRNA levels were determined by reverse transcriptrase polymerase chain reaction in hippocampus samples isolated every 4 hours during a 24-hour period. CAT and GPx enzymatic activities were also determined by kinetic assays. Regulatory regions of clock and antioxidant enzymes genes were scanned for E-box, RXRE, and CRE sites. E-box, RXRE, and CRE sites were found on regulatory regions of GPx and CAT genes, which display a circadian expression in the rat hippocampus. VAD phase shifted CAT, GPx, and RXRγ endogenous rhythms without affecting circadian expression of CREB1. CAT and GPx expression and enzymatic activity are circadian in the rat hippocampus. The VAD affected the temporal patterns antioxidant genes expression, probably by altering circadian rhythms of its RXR receptors and clock factors; thus, it would impair the temporal orchestration of hippocampal daily cognitive performance.

  19. GLUTATHIONE PEROXIDASE-1 PRO200LEU POLYMORPHISM (RS1050450) IS ASSOCIATED WITH MORBID OBESITY INDEPENDENTLY OF THE PRESENCE OF PREDIABETES OR DIABETES IN WOMEN FROM CENTRAL MEXICO.

    Science.gov (United States)

    Hernández Guerrero, César; Hernández Chávez, Paulina; Martínez Castro, Noemí; Parra Carriedo, Alicia; García Del Rio, Sandra; Pérez Lizaur, Ana

    2015-10-01

    obesity affects more than a third of Mexican population. Oxidative stress participates actively in the etiology of this phenomenon. Glutathione peroxidase-1 (GPX-1) plays a protective role against oxidative stress. The SNP Pro200Leu (rs10504050) has been reported to affect the activity of the enzyme. to determine the frequency of rs10504050 polymorphism in women with obesity and normal weight control, asses the concentration of peripheral TBARS and evaluate the consumption of pro and antioxidants. 104 women with obesity and 70 healthy controls (CG) were included in the study. Anthropometric, biochemical, clinical and dietary features were evaluated. GPx-1 rs10504050 was determined by PCR/RFLP method. TBARS was assayed spectrophotometrically in plasma. The subjects were stratified and compared by obesity grades and by subgroups of prediabetes and diabetes condition. Statistical analysis included ANOVA of Kruskal Wallis, Xi squared and Pearson correlation. for rs10504050 polymorphism there were differences (Xi2 = 6; p = 0.01) between frequency (0.61) of obese carriers (Pro/Leu plus Leu/Leu) and CG carriers (0.42), and between (Xi2 = 8; p = 0.004) morbid (IMC > 40) obesity (0.74) and CG carriers. The obese group (OB) showed a prevalence of 66% of prediabetes plus diabetes. There were no differences in frequencies of rs10504050 in OB with pre or diabetes versus CG, or versus obese participants without diabetes. TBARS concentration was greater in all the degrees of OB versus CG. GPx-1 Pro200Leu polymorphism was associated with obesity especially with morbid obesity, but not with obese participants with prediabetes or diabetes. Oxidative stress is present in all grades of obesity significantly. Copyright AULA MEDICA EDICIONES 2014. Published by AULA MEDICA. All rights reserved.

  20. Analysis of manganese superoxide dismutase (MnSOD: Ala-9Val and glutathione peroxidase (GSH-Px: Pro 197 Leu gene polymorphisms in mood disorders.

    Directory of Open Access Journals (Sweden)

    Birgül Elbozan Cumurcu

    2013-05-01

    Full Text Available We investigated the etiopathogenetic role of manganese superoxide dismutase (MnSOD (Ala-9Val and glutathione peroxidase (GSH-Px (Pro 197 Leu gene polymorphisms in patients diagnosed with major depressive disorder (MDD and bipolar I disorder (BD. Eighty patients with MDD, 82 patients with BD (total 162 patients and 96 healthy controls were enrolled in this study and genotyped using a Real Time-Quantitative Polymer Chain Reaction (RT-qPCR-based method. The patients with BD and MDD and the controls had a similar distribution of the genotypes and alleles in the Ala-9Val MnSOD gene polymorphism. Comparison of the MDD group and control group regarding the Pro197 Leu GSH-Px gene polymorphism revealed similar genotype distribution but different allele distribution. The BD group and control group were similar both for genotypes and for alleles when compared regarding the Pro 197 Leu GSH-Px gene polymorphism. The combined analysis (MDD plus BD also failed to find any association between the Ala-9Val MnSOD and Pro 197 Leu GSH-Px gene polymorphism. Although small statistical power of the current study the significant difference between patients with depression and the control group for the Pro 197 Leu GSH-Px polymorphism indicates that the distribution of these alleles may have a contribution in the physiopathogenesis of depression. One of the limitation of the current study is that the sample size is too small. Understanding of the exact role of Pro 197 LeuGSH-Px polymorphism in the development of depression needs to further studies with more sample size and high statistical power.

  1. Erythrocyte superoxide dismutase, glutathione peroxidase, and catalase activities and risk of coronary heart disease in generally healthy women: a prospective study.

    Science.gov (United States)

    Yang, Shuman; Jensen, Majken K; Rimm, Eric B; Willett, Walter; Wu, Tianying

    2014-11-01

    Erythrocyte antioxidant enzymes are major circulating antioxidant enzymes in the oxidative stress defense system. Few prospective studies have assessed the association between these enzymes and the risk of coronary heart disease (CHD) in generally healthy adults. We conducted a prospective nested case-control study of CHD among 32,826 women at baseline with 15 years of follow-up from 1989 to 2004 in the Nurses' Health Study. We investigated the association of baseline erythrocyte superoxide dismutase (SOD), glutathione peroxidase (GPx), and catalase (CAT) activities with the risk of CHD. A total of 365 cases and 728 controls were included in the analysis. Overall, the relative risks of CHD associated with 1-standard deviation higher SOD, GPx, and CAT activities were 1.07 (95% confidence interval (CI): 0.94, 1.22), 1.04 (95% CI: 0.91, 1.18), and 1.04 (95% CI: 0.92, 1.17), respectively. Multivariable adjustments did not change the associations appreciably. Fasting status did not modify the associations, with the exception that SOD activity was positively associated with the risk of CHD among participants who provided blood samples within 12 hours of fasting. Overall, activities of SOD, GPx, and CAT were not associated with CHD among women who were generally healthy at the time of blood collection. © The Author 2014. Published by Oxford University Press on behalf of the Johns Hopkins Bloomberg School of Public Health. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  2. Expression of inactive glutathione peroxidase 4 leads to embryonic lethality, and inactivation of the Alox15 gene does not rescue such knock-in mice.

    Science.gov (United States)

    Brütsch, Simone Hanna; Wang, Chi Chiu; Li, Lu; Stender, Hannelore; Neziroglu, Nilgün; Richter, Constanze; Kuhn, Hartmut; Borchert, Astrid

    2015-02-01

    Glutathione peroxidases (Gpx) and lipoxygenases (Alox) are functional counterplayers in the metabolism of hydroperoxy lipids that regulate cellular redox homeostasis. Gpx4 is a moonlighting protein that has been implicated not only as an enzyme in anti-oxidative defense, gene expression regulation, and programmed cell death, but also as a structural protein in spermatogenesis. Homozygous Gpx4 knock-out mice are not viable, but molecular reasons for intrauterine lethality are not completely understood. This study was aimed at investigating whether the lack of catalytic activity or the impaired function as structural protein is the dominant reason for embryonic lethality. We further explored whether the pro-oxidative enzyme mouse 12/15 lipoxygenase (Alox15) plays a major role in embryonic lethality of Gpx4-deficient mice. To achieve these goals, we first created knock-in mice, which express a catalytically inactive Gpx4 mutant (Sec46Ala). As homozygous Gpx4-knock-out mice Sec46Ala-Gpx4(+/+) knock-in animals are not viable but undergo intrauterine resorption between embryonic day 6 and 7 (E6-7). In contrast, heterozygous knock-in mice (Sec46Ala-Gpx4(-/+)) are viable, fertile and do not show major phenotypic alterations. Interestingly, homozygous Alox15 deficiency did not rescue the U46A-Gpx4(+/+) mice from embryonic lethality. In fact, when heterozygous U46A-Gpx4(-/+) mice were stepwise crossed into an Alox15-deficent background, no viable U46A-Gpx4(+/+)+Alox15(-/-) individuals were obtained. However, we were able to identify U46A-Gpx4(+/+)+Alox15(-/-) embryos in the state of resorption around E7. These data suggest that the lack of catalytic activity is the major reason for the embryonic lethality of Gpx4(-/-) mice and that systemic inactivation of the Alox15 gene does not rescue homozygous knock-in mice expressing catalytically silent Gpx4.

  3. Diphenyl diselenide protects against methylmercury-induced inhibition of thioredoxin reductase and glutathione peroxidase in human neuroblastoma cells: a comparison with ebselen.

    Science.gov (United States)

    Meinerz, Daiane F; Branco, Vasco; Aschner, Michael; Carvalho, Cristina; Rocha, João Batista T

    2017-09-01

    Exposure to methylmercury (MeHg), an important environmental toxicant, may lead to serious health risks, damaging various organs and predominantly affecting the brain function. The toxicity of MeHg can be related to the inhibition of important selenoenzymes, such as glutathione peroxidase (GPx) and thioredoxin reductase (TrxR). Experimental studies have shown that selenocompounds play an important role as cellular detoxifiers and protective agents against the harmful effects of mercury. The present study investigated the mechanisms by which diphenyl diselenide [(PhSe) 2 ] and ebselen interfered with the interaction of mercury (MeHg) and selenoenzymes (TrxR and GPx) in an in vitro experimental model of cultured human neuroblastoma cells (SH-SY5Y). Our results established that (PhSe) 2 and ebselen increased the activity and expression of TrxR. In contrast, MeHg inhibited TrxR activity even at low doses (0.5 μm). Coexposure to selenocompounds and MeHg showed a protective effect of (PhSe) 2 on both the activity and expression of TrxR. When selenoenzyme GPx was evaluated, selenocompounds did not alter its activity or expression significantly, whereas MeHg inhibited the activity of GPx (from 1 μm). Among the selenocompounds only (PhSe) 2 significantly protected against the effects of MeHg on GPx activity. Taken together, these results indicate a potential use for ebselen and (PhSe) 2 against MeHg toxicity. Furthermore, for the first time, we have demonstrated that (PhSe) 2 caused a more pronounced upregulation of TrxR than ebselen in neuroblastoma cells, likely reflecting an important molecular mechanism involved in the antioxidant properties of this compound. Copyright © 2017 John Wiley & Sons, Ltd. Copyright © 2017 John Wiley & Sons, Ltd.

  4. The synergistic effect of beta-boswellic acid and Nurr1 overexpression on dopaminergic programming of antioxidant glutathione peroxidase-1-expressing murine embryonic stem cells.

    Science.gov (United States)

    Abasi, M; Massumi, M; Riazi, G; Amini, H

    2012-10-11

    Parkinson's disease (PD) is a neurodegenerative disorder in which the nigro-striatal dopaminergic (DAergic) neurons have been selectively lost. Due to side effects of levodopa, a dopamine precursor drug, recently cell replacement therapy for PD has been considered. Lack of sufficient amounts of, embryos and ethical problems regarding the use of dopamine-rich embryonic neural cells have limited the application of these cells for PD cell therapy. Therefore, many investigators have focused on using the pluripotent stem cells to generate DAergic neurons. This study is aimed first to establish a mouse embryonic stem (mES) cell line that can stably co-express Nurr1 (Nuclear receptor subfamily 4, group A, member 2) transcription factor in order to efficiently generate DAergic neurons, and glutathione peroxidase-1 (GPX-1) to protect the differentiated DAergic-like cells against oxidative stress. In addition to genetic engineering of ES cells, the effect of Beta-boswellic acid (BBA) on DAergic differentiation course of mES cells was sought in the present study. To that end, the feeder-independent CGR8 mouse embryonic stem cells were transduced by Nurr1- and GPX-1-harboring Lentiviruses and the generated Nurr1/GPX-1-expresssing ES clones were characterized and verified. Gene expression analyses demonstrated that BBA treatment and overexpression of Nurr1 has a synergistic effect on derivation of DAergic neurons from Nurr1/GPX-1-expressing ES cells. The differentiated cells could exclusively synthesize and secrete dopamine in response to stimuli. Overexpression of GPX-1 in genetically engineered Nurr1/GPX-1-ES cells increased the viability of these cells during their differentiation into CNS stem cells. In conclusion, the results demonstrated that Nurr1-overexpressing feeder-independent ES cells like the feeder-dependent ES cells, can be efficiently programmed into functional DAergic neurons and additional treatment of cells by BBA can even augment this efficiency. GPX-1

  5. Mechanism of the reaction of ebselen with endogenous thiols : dihydrolipoate is a better cofactor than glutathione in the peroxidase activity of ebselen

    NARCIS (Netherlands)

    Haenen, G R; De Rooij, B M; Vermeulen, N P; Bast, A

    The therapeutic effect of ebselen has been linked to its peroxidase activity. In the present study, the peroxidase activity of ebselen toward H2O2 with the endogenous thiols GSH and dihydrolipoate [L(SH)2] as cofactors was determined. When GSH was used, peroxide removal was described by a ter uni

  6. Investigation of glutathione peroxidase activity in chicken meat under different experimental conditions Investigação da atividade de glutationa peroxidase em carne de frango submetida a diferentes condições experimentais

    Directory of Open Access Journals (Sweden)

    Alexandre José Cichoski

    2012-12-01

    Full Text Available Due to the fact that previous studies on the enzymatic activity of Glutathione peroxidase (GSH-Px diverge widely in their methodology and results, this study aimed to investigate the influence of different analytical conditions on GSH-Px activity in chicken thighs from broilers that were fed different diets with different sources and concentrations of selenium. GSH-Px activity was evaluated six hours after slaughter and 120 days after frozen storage at -18 ºC. The different analytical conditions included time of pre-incubation (0, 10 and 30 minutes, reaction medium, types of substrate (H2O2 (0.72 mM, 7.2 mM, and 72 mM and Terc-butil hydroperoxide 15 mM, and different buffer concentrations (buffer 1, potassium phosphate 50 mM pH 7.0 + EDTA 1 mM + mercaptoethanol 1 mM, and buffer 2, tris-HCl 50 mM pH 7.6 + EDTA 1 mM + mercapthanol 5 mM. The results show that the highest GSH-Px activity was observed when enzyme and substrate were in contact at 22 ºC without any pre-incubation, and that, when used at concentrations above 0.72 mM, hydrogen peroxide saturated the GSH-Px enzyme and inhibited its activity. The enzyme presented higher affinity to hydrogen peroxide when compared to terc-butil peroxide, and the addition of a buffer containing mercaptoethanol did not increase GSH-Px enzymatic activity. The activity of GSH-Px was not influenced by the source and concentration of selenium in the diet either. The obtained results allowed the determination of the best temperature of contact between the enzyme and substrate (22 ºC, the optimum concentration, and the type of substrate and buffer to be used. This information is extremely useful for future studies on GSH-Px activity in meat due to the divergence and little information found in the literature.Uma vez que estudos anteriores sobre a atividade enzimática da glutationa peroxidase (GSH-Px divergem acerca da metodologia e dos resultados, este estudo teve por objetivo investigar a influência de

  7. Phenylalanine ammonia-lyase (pal) and peroxidase activity in brown rust infected tissues of pakistani wheat cultivars

    International Nuclear Information System (INIS)

    Riaz, A.; Tahir, M.I.

    2014-01-01

    Besides other factors resistance and susceptibility is the outcome of biochemical processes such as activities of defense-related enzymes. So in this study, Phenylalanine ammonia-lyase (PAL) and Peroxidase activity of resistant (Inqilab-91) and susceptible (Kirin-95) wheat cultivars were determined through spectrophotometer to address the biochemical aspect related to the disease after 8 hours, 24 hours, 48 hours and 72 hours of leaf rust inoculation. The results have shown that these enzymes were present in both the resistant and susceptible cultivars but the activity was more pronounced in the resistant one. The effect of PAL and peroxidase activity was also investigated among inoculated and uninoculated plants within the same cultivar. The activity of both PAL and peroxidase were more significant in inoculated ones. The results have shown that the after 72 hours of inoculation Inqilab-91 had more PAL activity i.e., 5.47 IU/ml/min than in Kirin-95 i.e., 2.08 IU/ml/min at 270 nm. While peroxidase activity in Inqilab-91 was 6.41 IU/ml/min and in Kirin-95, 3.66 IU/ml/min after 72 hours of inoculation, observed under 470 nm wavelength. Increase in one's activity increases the other enzyme's activity. The activity was more prominent after 72 hours of infection as pathogen had successfully established itself in the host plant tissue. The activities of these enzymes act as plants active defense mechanism against the attack of pathogen. (author)

  8. Reduced glutathione concentration and glutathione reductase activity in various rat tissues after the administration of some radioprotective agents

    International Nuclear Information System (INIS)

    Pulpanova, J.; Kovarova, H.; Ledvina, M.

    1982-01-01

    The concentrations of reduced glutathione (GSH) and activity of glutathione reductase were investigated in rat liver, kidney and spleen after intraperitoneal administration of cystamine (50 mg/kg), mexamine (10 mg/kg), or a mixture of cystamine with mexamine (20 + 10 mg/kg). The GSH concentration increased after the administration of cystamine in the liver (maximum between the 20th and 30th min), in the kidney and spleen (maximum after 60 min). The cystamine + mexamine mixture also caused a significant increase of the GSH concentration in all the organs investigated; however, the values increased at earlier intervals as after the cystamine administration. No substantial effect was shown in the case of the mexamine administration, only 30 min after the administration the values were higher. The activity of glutathione reductase was significantly lower over the entire period examined. This was found in the liver and kidney as after the administration of cystamine, as after the radioprotective mixture. There was also a less pronounced inhibition of the enzyme activity in the spleen. Mexamine as a single radioprotector had practically no influence on the activity. (author)

  9. Effects of Gram-negative Bacteria, E.coli and Cold Exposure on Free Radicals Production, Lactate Dehydrogenase and Glutathione Peroxidase Activity in the Lungs of Rats, Rattus norvigicus

    International Nuclear Information System (INIS)

    AlSaid, A Haffor

    2007-01-01

    The purpose of this study was to explore the effects of LPS-gram negative bacteria and low ambient temperature on free radicals (FR) production, the activities of lactate dehydrogenase (LDH) and glutathione peroxidase (GPx) in the lungs of rats, Rattus norvigisu. Twenty four male rats, matched with age and weigh, were divided randomly into four groups namely control (C), Bacteria (B), cold temperature (T), and bacteria plus cold (BT). The T group was exposed to 10-12degree C ambient temperature for 3 days. Animals of the BT was injected LPS bacteria (IP, 500 micron g/kg) during the last five hour of cold exposure to 10-12 degree C for 3 days. In comparison with C group FR increased significantly (p<0.05) in the experimental groups, indicating high rate of reactive oxygen species (ROS) accumulation. The activity of LDH increased significantly (p<0.05) in the T and BT groups, which demonstrated that bacteria and exposure to cold are causes for cellular injury in the lungs. The synergetic effect of both bacteria and cold on LDH was more intense, as compared with the single effect. The activity of GPx increased significantly (p<0.05) in the B and BT, as compared with the C group. The results of the present study is the first worldwide report to demonstrate that both cold exposure and bacteria infection are mediated by elevation in FR generation. (author)

  10. Dietary Supplementation with the Microalga Galdieria sulphuraria (Rhodophyta) Reduces Prolonged Exercise-Induced Oxidative Stress in Rat Tissues

    OpenAIRE

    Carfagna, Simona; Napolitano, Gaetana; Barone, Daniela; Pinto, Gabriele; Pollio, Antonino; Venditti, Paola

    2015-01-01

    We studied the effects of ten-day 1% Galdieria sulphuraria dietary supplementation on oxidative damage and metabolic changes elicited by acute exercise (6-hour swimming) determining oxygen consumption, lipid hydroperoxides, protein bound carbonyls in rat tissue (liver, heart, and muscle) homogenates and mitochondria, tissue glutathione peroxidase and glutathione reductase activities, glutathione content, and rates of H2O2 mitochondrial release. Exercise increased oxidative damage in tissues a...

  11. Real-time quantification of subcellular H2O2 and glutathione redox potential in living cardiovascular tissues.

    Science.gov (United States)

    Panieri, Emiliano; Millia, Carlo; Santoro, Massimo M

    2017-08-01

    Detecting and measuring the dynamic redox events that occur in vivo is a prerequisite for understanding the impact of oxidants and redox events in normal and pathological conditions. These aspects are particularly relevant in cardiovascular tissues wherein alterations of the redox balance are associated with stroke, aging, and pharmacological intervention. An ambiguous aspect of redox biology is how redox events occur in subcellular organelles including mitochondria, and nuclei. Genetically-encoded Rogfp2 fluorescent probes have become powerful tools for real-time detection of redox events. These probes detect hydrogen peroxide (H 2 O 2 ) levels and glutathione redox potential (E GSH ), both with high spatiotemporal resolution. By generating novel transgenic (Tg) zebrafish lines that express compartment-specific Rogfp2-Orp1 and Grx1-Rogfp2 sensors we analyzed cytosolic, mitochondrial, and the nuclear redox state of endothelial cells and cardiomyocytes of living zebrafish embryos. We provide evidence for the usefulness of these Tg lines for pharmacological compounds screening by addressing the blocking of pentose phosphate pathways (PPP) and glutathione synthesis, thus altering subcellular redox state in vivo. Rogfp2-based transgenic zebrafish lines represent valuable tools to characterize the impact of redox changes in living tissues and offer new opportunities for studying metabolic driven antioxidant response in biomedical research. Copyright © 2017 Elsevier Inc. All rights reserved.

  12. Efeito da adição de glutationa peroxidase e cisteína ao diluidor de congelação do sêmen equino Effect of glutathione peroxidase and cysteine addition in an equine frozen semen medium

    Directory of Open Access Journals (Sweden)

    L.O. Barros

    2013-04-01

    Full Text Available Foram utilizados ejaculados (n=25 de garanhões para avaliar o efeito de glutationa peroxidase (GPx e cisteína na viabilidade de espermatozoides congelados. O sêmen foi diluído em Botu Crio, com antioxidantes, e foram formados os grupos: G1, Controle; G2, 1U GPx ; G3, 5U GPx; G4, 0,5mM cisteína; G5, 1mM cisteína. Depois foi envasado em palhetas (0,5mL e congelado. Após descongelação, 37°C por 30 segundos, alíquotas foram analisadas quanto à integridade de membrana plasmática (IMP e acrossoma (IAc, potencial de membrana mitocondrial (PMM e cinética, nos tempos zero (T0 e 60 minutos (T60. GPx 5U e cisteína 0,5mM determinaram maior (PEjaculates (n=25 of horses were used to assess the effect of glutathione peroxidase (GPx and cysteine on the viability of frozen sperm cells. Semen was extended at Botu Crio with antioxidants, and divided in groups: G1, control; G2, 1 U GPx; G3, 5U GPx; G4, 0.5mM cysteine and G5, 1mM cysteine, packed in 0.5mL straws, and frozen. After thawing (37° C for 30 seconds samples were analyzed for plasma membrane (IMP and acrosome integrity (IAc, mitochondrial membrane potential (MMP and kinematic, at zero (T0 and 60 minutes after (T60. GPx 5U and cysteine 0.5mM increased (P<0.05 IAc at T0, when compared to T60. Cysteine 1mM resulted in a higher (P<0.05 IAc on T60, than GPx 1 and 5U, and cysteine 0.5mM. The PMM from a stallion on T60 was higher (P<0.05 than those of two stallions. In sperm kinematic, VCL and VAP were higher (P<0.05 at T0 compared to T60 for the control group, and one stallion showed larger (P<0.05 kinematic values than other animals. It is concluded that the addition of glutathione peroxidase at concentrations 1U and 5U, and cysteine, at concentrations of 0.5mM and 1mM, does not interfere with the integrity of cryopreserved equine sperm, but preserves the kinetic parameters VCL and VAP after 60 minutes of incubation. It should be noted also that the stallion has a strong influence on sperm

  13. In vitro glutathione peroxidase mimicry of ebselen is linked to its oxidation of critical thiols on key cerebral suphydryl proteins - A novel component of its GPx-mimic antioxidant mechanism emerging from its thiol-modulated toxicology and pharmacology.

    Science.gov (United States)

    Kade, I J; Balogun, B D; Rocha, J B T

    2013-10-25

    The antioxidant mechanism of ebselen in rats brain is largely linked with its glutathione peroxidase (GPx) rather than its peroxiredoxin mimicry ability. However, the precise molecular dynamics between the GPx-mimicry of ebselen and thiol utilization is yet to be fully clarified and thus still open. Herein, we investigated the influence of dithiothreitol (DTT) on the antioxidant action of ebselen against oxidant-induced cerebral lipid peroxidation and deoxyribose degradation. Furthermore, the critical inhibitory concentrations of ebselen on the activities of sulphydryl enzymes such as cerebral sodium pump, δ-aminolevulinic acid dehydratase (δ-ALAD) and lactate dehydrogenase (LDH) were also investigated. We observe that ebselen (at ≥42 μM) markedly inhibited lipid peroxidation in the presence and absence of DTT, whereas it inhibited deoxyribose degradation only in the presence of DTT. Furthermore, under in vitro conditions, ebselen inhibited the thiol containing enzymes; cerebral sodium pump (at ≥40 μM), δ-ALAD (≥10 μM) and LDH (≥1 μM) which were either prevented or reversed by DTT. However, the inhibition of the activities of these sulphydryl proteins in diabetic animals was prevented by ebselen. Summarily, it is apparent that the effective in vitro inhibitory doses of ebselen on the activity of the sulphydryl proteins are far less than its antioxidant doses. In addition, the presence of DTT is evidently a critical requirement for ebselen to effect its antioxidant action against deoxyribose degeradation and not lipid peroxidation. Consequently, we conclude that ebselen possibly utilizes available thiols on sulphydryl proteins to effect its GPx mimicry antioxidant action against lipid peroxidation in rat brain homogenate. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

  14. Lipoic acid increases glutathione peroxidase, Na+, K+-ATPase and acetylcholinesterase activities in rat hippocampus after pilocarpine-induced seizures? O ácido lipóico aumenta as atividades da glutationa peroxidase, da Na+, K+-ATPase e da acetilcolinesterase no hipocampo de ratos após convulsões induzidas por pilocarpina?

    Directory of Open Access Journals (Sweden)

    Geane Felix de Souza

    2010-08-01

    Full Text Available In the present study we investigated the effects of lipoic acid (LA on acetylcholinesterase (AChE, glutathione peroxidase (GPx and Na+, K+-ATPase activities in rat hippocampus during seizures. Wistar rats were treated with 0.9% saline (i.p., control group, lipoic acid (20 mg/kg, i.p., LA group, pilocarpine (400 mg/kg, i.p., P400 group, and the association of pilocarpine (400 mg/kg, i.p. plus LA (20 mg/kg, i.p., 30 min before of administration of P400 (LA plus P400 group. After the treatments all groups were observed for 1 h. In P400 group, there was a significant increase in GPx activity as well as a decrease in AChE and Na+, K+-ATPase activities after seizures. In turn, LA plus P400 abolished the appearance of seizures and reversed the decreased in AChE and Na+, K+-ATPase activities produced by seizures, when compared to the P400 seizing group. The results from the present study demonstrate that preadministration of LA abolished seizure episodes induced by pilocarpine in rat, probably by increasing AChE and Na+, K+-ATPase activities in rat hippocampus.No presente estudo nós investigamos os efeitos do ácido lipóico (AL sobre as atividades da acetilcolinesterase (AChE, da glutationa peroxidase (GPx e da Na+, K+-ATPase no hipocampo de ratos durante crises convulsivas. Ratos Wistar foram tratados com solução salina a 0,9% (i.p., grupo controle, ácido lipóico (20 mg/kg, i.p., grupo AL, pilocarpina (400 mg/kg, i.p., grupo P400, e a associação de AL (20 mg/kg, i.p. com a pilocarpina (400 mg/kg, i.p., 30 min antes da administração de pilocarpina (grupo AL + P400. Após os tratamentos todos os grupos foram observados durante 1 h. No grupo P400, houve um aumento significativo na atividade da GPx, assim como uma diminuição das atividades da AChE e Na+, K+-ATPase. Por sua vez, o pré-tratamento com AL aboliu o aparecimento de convulsões e reverteu a diminuição das atividades da AChE e da Na+, K+-ATPase causadas pelas convulsões, quando

  15. Effect of cadmium on glutathione S-transferase and metallothionein gene expression in coho salmon liver, gill and olfactory tissues

    International Nuclear Information System (INIS)

    Espinoza, Herbert M.; Williams, Chase R.; Gallagher, Evan P.

    2012-01-01

    Highlights: ► Developed qPCR assays to distinguish closely related GST isoforms in salmon. ► Examined the effect of cadmium on GST and metallothionein genes in 3 tissues. ► Modulation of GST varied among isoforms, tissues, and included a loss of expression. ► Metallothionein outperformed, but generally complemented, GSTs as biomarkers. ► Salmon olfactory genes were among the most responsive to cadmium. - Abstract: The glutathione S-transferases (GSTs) are a multifunctional family of phase II enzymes that detoxify a variety of environmental chemicals, reactive intermediates, and secondary products of oxidative damage. GST mRNA expression and catalytic activity have been used as biomarkers of exposure to environmental chemicals. However, factors such as species differences in induction, partial analyses of multiple GST isoforms, and lack of understanding of fish GST gene regulation, have confounded the use of GSTs as markers of pollutant exposure. In the present study, we examined the effect of exposure to cadmium (Cd), a prototypical environmental contaminant and inducer of mammalian GST, on GST mRNA expression in coho salmon (Oncorhynchus kisutch) liver, gill, and olfactory tissues. GST expression data were compared to those for metallothionein (MT), a prototypical biomarker of metal exposure. Data mining of genomic databases led to the development of quantitative real-time PCR (qPCR) assays for salmon GST isoforms encompassing 9 subfamilies, including alpha, mu, pi, theta, omega, kappa, rho, zeta and microsomal GST. In vivo acute (8–48 h) exposures to low (3.7 ppb) and high (347 ppb) levels of Cd relevant to environmental scenarios elicited a variety of transient, albeit minor changes (<2.5-fold) in tissue GST profiles, including some reductions in GST mRNA expression. In general, olfactory GSTs were the earliest to respond to cadmium, whereas, more pronounced effects in olfactory and gill GST expression were observed at 48 h relative to earlier time

  16. Cloning and characterization of an ascorbate peroxidase gene ...

    African Journals Online (AJOL)

    DR. NJ TONUKARI

    2012-05-29

    May 29, 2012 ... Real-time quantitative polymerase chain reaction was used to explore expression patterns of. MaAPX1 in ... and the activity of a number of enzymatic systems, including ... peroxidase (APX), glutathione reductase and catalase.

  17. ENDURANCE TRAINING AND GLUTATHIONE-DEPENDENT ANTIOXIDANT DEFENSE MECHANISM IN HEART OF THE DIABETIC RATS

    Directory of Open Access Journals (Sweden)

    Mustafa Atalay

    2003-06-01

    Full Text Available Regular physical exercise beneficially influences cardiac antioxidant defenses in normal rats. The aim of this study was to test whether endurance training can strengthen glutathione-dependent antioxidant defense mechanism and decrease lipid peroxidation in heart of the streptozotocin-induced diabetic rats. Redox status of glutathione in blood of diabetic rats in response to training and acute exercise was also examined. Eight weeks of treadmill training increased the endurance in streptozotocin-induced diabetic rats. It did not affect glutathione level in heart tissue at rest and also after exercise. On the other hand, endurance training decreased glutathione peroxidase activity in heart, while glutathione reductase and glutathione S-transferase activities were not affected either by acute exhaustive exercise or endurance training. Reduced and oxidized glutathione levels in blood were not affected by either training or acute exercise. Conjugated dienes levels in heart tissue were increased by acute exhaustive exercise and also 8 weeks treadmill training. Longer duration of exhaustion in trained group may have contributed to the increased conjugated dienes levels in heart after acute exercise. Our results suggest that endurance type exercise may make heart more susceptible to oxidative stress. Therefore it may be wise to combine aerobic exercise with insulin treatment to prevent its adverse effects on antioxidant defense in heart in patients with diabetes mellitus

  18. Glutathione S-transferases in human renal cortex and neoplastic tissue: enzymatic activity, isoenzyme profile and immunohistochemical localization.

    Science.gov (United States)

    Rodilla, V; Benzie, A A; Veitch, J M; Murray, G I; Rowe, J D; Hawksworth, G M

    1998-05-01

    1. Glutathione S-transferase (GST) activity in the cytosol of renal cortex and tumours from eight men and eight women was measured using 1-chloro-2,4-dinitrobenzene (CDNB) as a substrate. GST activities ranged from 685 to 2192 nmol/min/mg protein in cortex (median 1213) and from non-detectable (minimum 45) to 2424 nmol/min/mg protein in tumours (median 469). The activities in the tumours were lower than those in the normal cortices (p 0.05). 3. The age of the patients ranged from 42 to 81 years (median 62) and was not found to play a role in the levels of GST activity observed in cortex or in renal tumours from either sex. 4. Immunoblotting and immunohistochemical studies confirmed that GST-alpha was the predominant form expressed both in normal cortex and tumour and probably accounted for most of the GST activity present in these samples. GST-mu and GST-phi were expressed in both tumours and normal cortex and, while in some cases the level of expression in the cortices was higher than that found in the tumours, the reverse was also observed. Within the GST-mu class, GST M1/M2 was only detected in one sample (tumour), which showed the highest overall expression of GST-mu. GSTM3 was the predominant isoenzyme of the mu class in normal and tumour tissue, whereas GTM4 and GSTM5 were not detected. 5. These differences could have functional significance where xenobiotics or cytotoxic drugs are specific substrates for the different classes of GSTs.

  19. Glutathione level and its relation to radiation therapy in patients with cancer of uterine cervix

    International Nuclear Information System (INIS)

    Mukundan, H.; Bahadur, A.K.; Kumar, A.; Sardana, S.; Naik, S.L.D.; Ray, A.; Sharma, B.K.

    1999-01-01

    Glutathione functions as an important antioxidant in the destruction of hydrogen peroxide and lipid peroxides by providing substrate for the glutathione peroxidase and also promotes the ascorbic acid. Glutathione plays a vital role in detoxification of xenobiotics, carcinogens, free radicals and maintenance of immune functions. The study was aimed to determine plasma glutathione as well as erythrocyte glutathione and glutathione peroxidase in patients with invasive cervical carcinoma (n=30) before initiation and after completion of radiotherapy and subsequently, at the time of first three monthly follow-up visit. The levels of plasma glutathione, erythrocyte glutathione and glutathione peroxidase activity were found to be lower in all cervical cancer patients as compared to age matched normal control women. The study indicates a change in antioxidant status in relation with the glutathione system among patients with invasive carcinoma of the uterine cervix. This study also demonstrates the effect of radiation therapy on this antioxidant system. (author)

  20. In vivo and in vitro assessment of the role of glutathione antioxidant system in anthracycline-induced cardiotoxicity

    Czech Academy of Sciences Publication Activity Database

    Vávrová, A.; Popelová, O.; Štěrba, M.; Jirkovský, E.; Hašková, P.; Mertlíková-Kaiserová, Helena; Geršl, V.; Šimůnek, T.

    2011-01-01

    Roč. 85, č. 5 (2011), s. 525-535 ISSN 0340-5761 Grant - others:GA ČR(CZ) GA305/09/0416 Program:GA Institutional research plan: CEZ:AV0Z40550506 Keywords : anthracycline cardiotoxicity * daunorubicin * glutathione * glutathione peroxidase * glutathione peroxidase Subject RIV: CE - Biochemistry Impact factor: 4.674, year: 2011

  1. OXIDATIVE MODIFICATION OF PROTEINS AND GLUTATHIONE SYSTEM IN ADIPOCYTES UNDER DIABETES

    Directory of Open Access Journals (Sweden)

    Ye. V. Shakhristova

    2014-01-01

    Full Text Available Currently, diabetes ranks third in relation to medical and social significance after cardiovascular diseases and cancer and is the leading cause of blindness; it greatly increases the risk of myocardial infarction, coronary heart disease, nephropathy and hypertension in patients with this disorder; therefore clinical and experimental studies aimed at investigation of diabetes emergence and development mechanisms are urgent.The aim of the study was to investigate the status of oxidative modification of proteins and glutathionedependent antioxidant defense system in adipocytes of rats with alloxan diabetes under conditions of oxidative stress.Material and methods. Development of type 1 diabetes was induced in rats by alloxan administration (90 mg/kg of body mass. Adipocytes were obtained from epididymal adipose tissue of rats. The level of carbonyl derivatives of proteins, oxidized tryptophan, bityrosine, general, reduced, oxygenated and protein-bound glutathione, as well as glutathione peroxidase activity in adipocytes of rats was determined.Results. In adipocytes of rats with alloxan diabetes, concentration of carbonyl derivatives of proteins, bityrosine and oxidized tryptophan increased on the background of redox-potential of glutathione system and glutathione peroxidase activity decrease.Conclusion. The obtained data indicate the activation of free-radical oxidation of proteins and reduction of antioxidant defense under conditions of oxidative stress in the adipose tissue of rats with alloxan diabetes; this process plays an important role in pathogenesis of diabetes and its complications development.

  2. Glutathione role in gallium induced toxicity

    African Journals Online (AJOL)

    Asim

    2012-01-26

    GSH) present in tissues. It is very important and interesting to study the reaction of gallium nitrate and glutathione as biomarker of glutathione role in detoxification and conjugation in whole blood components (plasma and ...

  3. Characterization of inter-tissue and inter-strain variability of TCE glutathione conjugation metabolites DCVG, DCVC, and NAcDCVC in the mouse.

    Science.gov (United States)

    Luo, Yu-Syuan; Furuya, Shinji; Chiu, Weihsueh; Rusyn, Ivan

    2018-01-01

    Trichloroethylene (TCE) is a ubiquitous environmental toxicant that is a liver and kidney carcinogen. Conjugation of TCE with glutathione (GSH) leads to formation of nepthrotoxic and mutagenic metabolites postulated to be critical for kidney cancerdevelopment; however, relatively little is known regarding their tissue levels as previous analytical methods for their detection lacked sensitivity. Here, an LC-MS/MS-based method for simultaneous detection of S-(1,2-dichlorovinyl)-glutathione (DCVG), S-(1,2-dichlorovinyl)-L-cysteine (DCVC), and N-acetyl-S-(1,2-dichlorovinyl)-L-cysteine (NAcDCVC) in multiple mouse tissues was developed. This analytical method is rapid, sensitive (limits of detection (LOD) 3-30 fmol across metabolites and tissues), and robust to quantify all three metabolites in liver, kidneys, and serum. The method was used to characterize inter-tissue and inter-strain variability in formation of conjugative metabolites of TCE. Single oral dose of TCE (24, 240 or 800 mg/kg) was administered to male mice from 20 inbred strains of Collaborative Cross. Inter-strain variability in the levels of DCVG, DCVC, and NAcDCVC (GSD = 1.6-2.9) was observed. Whereas NAcDCVC was distributed equally among analyzed tissues, highest levels of DCVG were detected in liver and DCVC in kidneys. Evidence indicated that inter-strain variability in conjugative metabolite formation of TCE might affect susceptibility to adverse health effects and that this method might aid in filling data gaps in human health assessment of TCE.

  4. Molecular cloning and tissue-specific transcriptional regulation of the first peroxidase family member, Udp1, in stinging nettle (Urtica dioica).

    Science.gov (United States)

    Douroupi, Triantafyllia G; Papassideri, Issidora S; Stravopodis, Dimitrios J; Margaritis, Lukas H

    2005-12-05

    A full-length cDNA clone, designated Udp1, was isolated from Urtica dioica (stinging nettle), using a polymerase chain reaction based strategy. The putative Udp1 protein is characterized by a cleavable N-terminal signal sequence, likely responsible for the rough endoplasmic reticulum entry and a 310 amino acids mature protein, containing all the important residues, which are evolutionary conserved among different members of the plant peroxidase family. A unique structural feature of the Udp1 peroxidase is defined into the short carboxyl-terminal extension, which could be associated with the vacuolar targeting process. Udp1 peroxidase is differentially regulated at the transcriptional level and is specifically expressed in the roots. Interestingly, wounding and ultraviolet radiation stress cause an ectopic induction of the Udp1 gene expression in the aerial parts of the plant. A genomic DNA fragment encoding the Udp1 peroxidase was also cloned and fully sequenced, revealing a structural organization of three exons and two introns. The phylogenetic relationships of the Udp1 protein to the Arabidopsis thaliana peroxidase family members were also examined and, in combination with the homology modelling approach, dictated the presence of distinct structural elements, which could be specifically involved in the determination of substrate recognition and subcellular localization of the Udp1 peroxidase.

  5. Arabidopsis thaliana peroxidase N

    DEFF Research Database (Denmark)

    Mirza, Osman Asghar; Henriksen, A; Ostergaard, L

    2000-01-01

    The structure of the neutral peroxidase from Arabidopsis thaliana (ATP N) has been determined to a resolution of 1.9 A and a free R value of 20.5%. ATP N has the expected characteristic fold of the class III peroxidases, with a C(alpha) r.m.s.d. of 0.82 A when compared with horseradish peroxidase C...

  6. Glutathione system participation in thoracic aneurysms from patients with Marfan syndrome.

    Science.gov (United States)

    Zúñiga-Muñoz, Alejandra María; Pérez-Torres, Israel; Guarner-Lans, Verónica; Núñez-Garrido, Elías; Velázquez Espejel, Rodrigo; Huesca-Gómez, Claudia; Gamboa-Ávila, Ricardo; Soto, María Elena

    2017-05-01

    Aortic dilatation in Marfan syndrome (MFS) is progressive. It is associated with oxidative stress and endothelial dysfunction that contribute to the early acute dissection of the vessel and can result in rupture of the aorta and sudden death. We evaluated the participation of the glutathione (GSH) system, which could be involved in the mechanisms that promote the formation and progression of the aortic aneurysms in MFS patients. Aortic aneurysm tissue was obtained during chest surgery from eight control subjects and 14 MFS patients. Spectrophotometrical determination of activity of glutathione peroxidase (GPx), glutathione-S-transferase (GST), glutathione reductase (GR), lipid peroxidation (LPO) index, carbonylation, total antioxidant capacity (TAC), and concentration of reduced and oxidized glutathione (GSH and GSSG respectively), was performed in the homogenate from aortic aneurysm tissue. LPO index, carbonylation, TGF-β1, and GR activity were increased in MFS patients (p < 0.04), while TAC, GSH/GSSG ratio, GPx, and GST activity were significantly decreased (p < 0.04). The depletion of GSH, in spite of the elevated activity of GR, not only diminished the activity of GSH-depend GST and GPx, but increased LPO, carbonylation and decreased TAC. These changes could promote the structural and functional alterations in the thoracic aorta of MFS patients.

  7. Peroxidase enzymes regulate collagen extracellular matrix biosynthesis.

    Science.gov (United States)

    DeNichilo, Mark O; Panagopoulos, Vasilios; Rayner, Timothy E; Borowicz, Romana A; Greenwood, John E; Evdokiou, Andreas

    2015-05-01

    Myeloperoxidase and eosinophil peroxidase are heme-containing enzymes often physically associated with fibrotic tissue and cancer in various organs, without any direct involvement in promoting fibroblast recruitment and extracellular matrix (ECM) biosynthesis at these sites. We report herein novel findings that show peroxidase enzymes possess a well-conserved profibrogenic capacity to stimulate the migration of fibroblastic cells and promote their ability to secrete collagenous proteins to generate a functional ECM both in vitro and in vivo. Mechanistic studies conducted using cultured fibroblasts show that these cells are capable of rapidly binding and internalizing both myeloperoxidase and eosinophil peroxidase. Peroxidase enzymes stimulate collagen biosynthesis at a post-translational level in a prolyl 4-hydroxylase-dependent manner that does not require ascorbic acid. This response was blocked by the irreversible myeloperoxidase inhibitor 4-amino-benzoic acid hydrazide, indicating peroxidase catalytic activity is essential for collagen biosynthesis. These results suggest that peroxidase enzymes, such as myeloperoxidase and eosinophil peroxidase, may play a fundamental role in regulating the recruitment of fibroblast and the biosynthesis of collagen ECM at sites of normal tissue repair and fibrosis, with enormous implications for many disease states where infiltrating inflammatory cells deposit peroxidases. Copyright © 2015 American Society for Investigative Pathology. Published by Elsevier Inc. All rights reserved.

  8. Peroxidases in nanostructures

    Directory of Open Access Journals (Sweden)

    Ana Maria eCarmona-Ribeiro

    2015-09-01

    Full Text Available Peroxidases are enzymes catalyzing redox reactions that cleave peroxides. Their active redox centers have heme, cysteine thiols, selenium, manganese and other chemical moieties. Peroxidases and their mimetic systems have several technological and biomedical applications such as environment protection, energy production, bioremediation, sensors and immunoassays design and drug delivery devices. The combination of peroxidases or systems with peroxidase-like activity with nanostructures such as nanoparticles, nanotubes, thin films, liposomes, micelles, nanoflowers, nanorods and others is often an efficient strategy to improve catalytic activity, targeting and reusability.

  9. Soapwort extract supplementation alters antioxidant status of serum, liver and heart tissues in growing Japanese quails reared under chronic intermittent cold stress

    Directory of Open Access Journals (Sweden)

    Bestami Dalkilic

    2017-01-01

    Full Text Available Antioxidant effect of dietary soapwort extract supplementation was studied in growing Japanese quails suffering from chronic intermittent cold stress. For this purpose, a total of ninety 15-d-old quails were divided into three groups with three replicates. Chronic intermittent cold stress was applied every night between 22.00 to 06.00 h; starting at 14 °C for the first week, and gradually weekly lowered to 8 °C. Three groups were fed with corn-soy based standard diets supplemented with 0, 50, and 100 ppm soapwort extract for four weeks. At the end of the study, three males and three females were slaughtered to determine total antioxidant and oxidant status of serum, malondialdehyde, glutathione, glutathione peroxidase activity, superoxide dismutase of liver and heart tissues. Although the dietary soapwort extract had no effect on serum total antioxidant capacity, it significantly lowered the total oxidant status of serum in cold stressed quails. Glutathione and superoxide dismutase enzyme activity of liver and heart tissues were similar among groups. While the dietary soapwort extract had no effect on glutathione peroxidase activity of the heart tissue, it significantly increased glutathione peroxidase activity in the liver tissue. In relation to the control group, malondialdehyde concentrations in the liver and heart tissues were significantly lower in soapwort extract groups. These data suggest that dietary soapwort extract could alleviate the detrimental effects of oxidative stress in growing Japanese quails exposed to cold stress.

  10. Selenium concentrations and enzyme activities of glutathione metabolism in wild long-tailed ducks and common eiders

    Science.gov (United States)

    Franson, J. Christian; Hoffman, David J.; Flint, Paul L.

    2011-01-01

    The relationships of selenium (Se) concentrations in whole blood with plasma activities of total glutathione peroxidase, Se-dependent glutathione peroxidase, and glutathione reductase were studied in long-tailed ducks (Clangula hyemalis) and common eiders (Somateria mollissima) sampled along the Beaufort Sea coast of Alaska, USA. Blood Se concentrations were >8 μg/g wet weight in both species. Linear regression revealed that the activities of total and Se-dependent glutathione peroxidase were significantly related to Se concentrations only in long-tailed ducks, raising the possibility that these birds were experiencing early oxidative stress.

  11. Peroxidase activity as a marker for estrogenicity

    International Nuclear Information System (INIS)

    Levy, J.; Liel, Y.; Glick, S.M.

    1981-01-01

    We examined the possibility that peroxidase activity might be a marker for estrogen activity in established estrogen-dependent tissues: dimethylbenz[a]anthracene (DMBA)-induced rat mammary tumours and human breast cancer. In DMBA-induced tumours undergoing regression after ovariectomy or tamoxifen treatment, tumour size decreased by 50%, estradiol receptors (ER) and progesterone receptors (PgR) decreased by 25 and 20%, respectively, but peroxidase activity paradoxically increased six- to sevenfold. In DMBA tumours stimulated by estradiol treatment or by the cessation of tamoxifen administration in intact rats, tumour size increased threefold. ER and PgR increased two- and threefold, respectively, while peroxidase activity decreased 50%. These data indicate an inverse relation between tumour growth, ER and PgR on the one hand, and peroxidase activity on the other. In the human breast cancers there was a singificant negative relation between the presence of ER and peroxidase activity. By using a calibrated Sephadex G-100 column it was shown that uterine peroxidase differs in molecular weight from the peroxidase of rat mammary tumours and that of human breast cancer. (author)

  12. Comparing the impact of melatonin and captopril on early effects of radiation on the heart tissue by studying glutathione, malondialdehyde, and lactate dehydrogenase enzyme activity in rats

    International Nuclear Information System (INIS)

    Shirazi, Alireza; Tabatabaie, Farnaz; Ghazi-Khansari, Mahmoud; Mirzaei, Hamidreza

    2015-01-01

    Prevention of secondary malignancy while the patient is receiving radiotherapy for the management of primary cancer has been an enormous challenge for biological and medical safety. The aim of the study is to compare protective effects of melatonin and captopril on early effects of radiation on the heart tissue of rats. Forty-eight adult male Wistar rats weighing 180-220 g were used. The rats were divided into six groups and the rats were exposed to 8 Gy whole body dose from Cobalt-60 sources. Thirty minutes prior to irradiation, six animals received melatonin (100 mg/kg body weight), and six animals received captopril (50 mg/kg body weight). All groups were sacrificed 10 days post-irradiation, and hearts were collected. Malondialdehyde (MDA), lactate dehydrogenase (LDH), and glutathione (GSH) were measured to evaluate cellular oxidative stress-induced injury. The biochemical data are presented as mean ± standard error of the mean, and the difference between the groups was analyzed using a two-way variance analysis. Treatment with captopril resulted in a significant increase in LDH and MDA, although the level of GSH was decreased (P < 0.01). MDA and LDH levels were decreased after melatonin treatment while GSH level was increased (P < 0.001). Melatonin has protective effects following radiation, while treatment with captopril post-irradiation seems to be radiosensitizing and does not have protective effects against radiation exposure. (author)

  13. Comprehensive genome-wide analysis of Glutathione S-transferase gene family in potato (Solanum tuberosum L.) and their expression profiling in various anatomical tissues and perturbation conditions.

    Science.gov (United States)

    Islam, Md Shiful; Choudhury, Mouraj; Majlish, Al-Nahian Khan; Islam, Tahmina; Ghosh, Ajit

    2018-01-10

    Glutathione S-transferases (GSTs) are ubiquitous enzymes which play versatile functions including cellular detoxification and stress tolerance. In this study, a comprehensive genome-wide identification of GST gene family was carried out in potato (Solanum tuberosum L.). The result demonstrated the presence of at least 90 GST genes in potato which is greater than any other reported species. According to the phylogenetic analyses of Arabidopsis, rice and potato GST members, GSTs could be subdivided into ten different classes and each class is found to be highly conserved. The largest class of potato GST family is tau with 66 members, followed by phi and lambda. The chromosomal localization analysis revealed the highly uneven distribution of StGST genes across the potato genome. Transcript profiling of 55 StGST genes showed the tissue-specific expression for most of the members. Moreover, expression of StGST genes were mainly repressed in response to abiotic stresses, while largely induced in response to biotic and hormonal elicitations. Further analysis of StGST gene's promoter identified the presence of various stress responsive cis-regulatory elements. Moreover, one of the highly stress responsive StGST members, StGSTU46, showed strong affinity towards flurazole with lowest binding energy of -7.6kcal/mol that could be used as antidote to protect crop against herbicides. These findings will facilitate the further functional and evolutionary characterization of GST genes in potato. Copyright © 2017 Elsevier B.V. All rights reserved.

  14. Evaluating Superoxide Dismutase (SOD, Glutathione (GSH, Malondialdehyde (MDA and the Histological Changes of the Lung Tissue after γ-Irradiation in Rats

    Directory of Open Access Journals (Sweden)

    Abolhasan Rezaeyan

    2016-09-01

    Full Text Available Background & Objective: The lung is a radiosensitive organ and its damage is a dose-limiting factor in radiotherapy. Different side effects such as pneumonia and lung fibrosis are found in patients with thorax irradiation. The objective of the present study is to evaluate the effects of γ-irradiation on acute and chronic injuries of lung tissue in rats. Materials & Methods: 32 rats were divided into two groups. Control group consisted of 14 rats that underwent shame irradiation. In radiation group, 18 rats underwent γ-irradiation. The rats were exposed to γ-irradiation 18 Gy using a single fraction cobalt-60 unit. Eight rats in each group were sacrificed 24 hours after radiotherapy for determining Superoxide Dismutase (SOD, Glutathione (GSH, Malondialdehyde (MDA, and histopathological evaluations. Remained animals were sacrificed eight weeks after radiotherapy for histopathological evaluation. Results: Compared to control group, the level of SOD and GSH significantly decreased and MDA level significantly increased in radiation group 24 hours following irradiation, (p=0.001, p<0.001, p=0.001 respectively. Early histopathological results after 24 hours showed that radiation increases neutrophil, macrophage, and inflammation incidence compared to control group (p<0.05. Late histopathological evaluation after eight weeks revealed significant increase in factors including mast cells, pulmonary edema, vascular thickness, vascular damage, and also inflammation and fibrosis incidence in case group compared to radiation group  (p<0.05. Conclusion: Localized chest radiation with dose of 18 Gy induces changes in oxidative stress indices and histopathological lung tissue damage in short and long term.

  15. Wound-induced ethylene synthesis and expression and formation of 1-aminocyclopropane-1-carboxylate (ACC) synthase, ACC oxidase, phenylalanine ammonia-lyase, and peroxidase in wounded mesocarp tissue of Cucurbita maxima.

    Science.gov (United States)

    Kato, M; Hayakawa, Y; Hyodo, H; Ikoma, Y; Yano, M

    2000-04-01

    1-Aminocyclopropane-1-carboxylate (ACC) synthase was rapidly induced in mesocarp tissue of Cucurbita maxima after wounding in the cut surface layer in 1 mm thickness (ca. 9 cells) (first layer) in both the enzyme activity and the levels of transcript. This led to a rapid accumulation of ACC and hence ethylene production. In the inside tissue (1-2 mm) (second layer), no significant induction of ACC synthase was observed, which resulted in a low level of ACC, although ethylene was evolved at a much lower rate than the first one. In contrast to ACC synthase, ACC oxidase was induced markedly in both the first and second layers and the development of its activity and the levels of mRNA remained high until later stages. It was considered that wound ethylene was closely associated with the development of ACC oxidase, since 2,5-norbornadiene (NBD), an inhibitor of ethylene action, substantially suppressed it. Phenylalanine ammonia-lyase (PAL) greatly increased in activity after wounding similarly to that of ACC synthase, in which increase in PAL activity occurred predominantly in the first layer. Induction of peroxidase activity after wounding had a close correlation in profile with that of ACC oxidase in that marked increases in the activity were observed in both the first and second layers and were strongly suppressed by NBD application. Four peroxidase isozymes were found by PAGE, among which a fraction was newly detected after wounding.

  16. Baseline Glutathione Peroxidase Activity Affects Prognosis after Acute Coronary Syndromes

    OpenAIRE

    García-Pinilla, José Manuel; Gálvez, Julio; Cabrera-Bueno, Fernando; Jiménez-Navarro, Manuel; Gómez-Doblas, Juan José; Galisteo, Milagros; Camuesco, Desiré; de Teresa Galván, Carlos; Espinosa-Caliani, Salvador; Zarzuelo, Antonio; de Teresa-Galván, Eduardo

    2008-01-01

    Oxidative stress is associated with atherosclerosis and plaque lesions in experimental in vitro models. Few in vivo studies have examined the association between redox status and the prognosis of acute coronary syndromes.

  17. Association between Polymorphisms in Glutathione Peroxidase and Selenoprotein P Genes, Glutathione Peroxidase Activity, HRT Use and Breast Cancer Risk

    DEFF Research Database (Denmark)

    Méplan, Catherine; Dragsted, Lars Ove; Ravn-Haren, Gitte

    2013-01-01

    Breast cancer (BC) is one of the most common cancers in women. Evidence suggests that genetic variation in antioxidant enzymes could influence BC risk, but to date the relationship between selenoproteins and BC risk remains unclear. In this report, a study population including 975 Danish cases...... and 975 controls matched for age and hormone replacement therapy (HRT) use was genotyped for five functional single nucleotide polymorphisms (SNPs) in SEPP1, GPX1, GPX4 and the antioxidant enzyme SOD2 genes. The influence of genetic polymorphisms on breast cancer risk was assessed using conditional...... logistic regression. Additionally pre-diagnosis erythrocyte GPx (eGPx) activity was measured in a sub-group of the population. A 60% reduction in risk of developing overall BC and ductal BC was observed in women who were homozygous Thr carriers for SEPP1 rs3877899. Additionally, Leu carriers for GPX1 Pro...

  18. Arabidopsis thaliana peroxidase N

    DEFF Research Database (Denmark)

    Mirza, Osman Asghar; Henriksen, A; Ostergaard, L

    2000-01-01

    The structure of the neutral peroxidase from Arabidopsis thaliana (ATP N) has been determined to a resolution of 1.9 A and a free R value of 20.5%. ATP N has the expected characteristic fold of the class III peroxidases, with a C(alpha) r.m.s.d. of 0.82 A when compared with horseradish peroxidase C...... (HRP C). HRP C is 54% identical to ATP N in sequence. When the structures of four class III plant peroxidases are superimposed, the regions with structural differences are non-randomly distributed; all are located in one half of the molecule. The architecture of the haem pocket of ATP N is very similar...... to that of HRP C, in agreement with the low small-molecule substrate specificity of all class III peroxidases. The structure of ATP N suggests that the pH dependence of the substrate turnover will differ from that of HRP C owing to differences in polarity of the residues in the substrate-access channel. Since...

  19. Expression, purification and characterization of a peroxidase from ...

    African Journals Online (AJOL)

    Peroxidase is one of the key enzymes of the cellular antioxidant defense system, which is mostly involved in the reduction of hydrogen peroxide. Here, a peroxidase gene, named ThPOD1 was isolated from a cDNA library, which was generated from root tissue of Tamarix hispida that was exposed to 0.4 M NaCl. The cDNA ...

  20. Expression of an enzymatically active Yb3 glutathione S-transferase in Escherichia coli and identification of its natural form in rat brain.

    Science.gov (United States)

    Abramovitz, M; Ishigaki, S; Felix, A M; Listowsky, I

    1988-11-25

    Glutathione S-transferases containing Yb3 subunits are relatively uncommon forms that are expressed in a tissue-specific manner and have not been identified unequivocally or characterized. A cDNA clone containing the entire coding sequence of Yb3 glutathione S-transferase mRNA was incorporated into a pIN-III expression vector used to transform Escherichia coli. A fusion Yb3-protein containing 14 additional amino acid residues at its N terminus was purified to homogeneity. Recombinant Yb3 was enzymatically active with both 1-chloro-2,4-dinitrobenzene and 1,2-dichloro-4-nitrobenzene as substrates but lacked glutathione peroxidase activity. Substrate specificity patterns of recombinant Yb3 were more limited than those of glutathione S-transferase isoenzymes containing Yb1- or Yb2-type subunits. Peptides corresponding to unique amino acid sequences of Yb3 as well as a peptide from a region of homology with Yb1 and Yb2 subunits were synthesized. These synthetic peptides were used to raise antibodies specific to Yb3 and others that cross-reacted with all Yb forms. Immunoblotting was utilized to identify the natural counterpart of recombinant Yb3 among rat glutathione transferases. Brain and testis glutathione S-transferases were rich in Yb3 subunits, but very little was found in liver or kidney. Physical properties, substrate specificities, and binding patterns of the recombinant protein paralleled properties of the natural isoenzyme isolated from brain.

  1. Low activity of superoxide dismutase and high activity of glutathione reductase in erythrocytes from centenarians

    DEFF Research Database (Denmark)

    Andersen, Helle Raun; Jeune, B; Nybo, H

    1998-01-01

    aged between 60 and 79 years. MEASUREMENTS: enzyme activities of superoxide dismutase (CuZn-SOD), glutathione peroxidase, catalase and glutathione reductase (GR) in erythrocytes. Functional capacity among the centenarians was evaluated by Katz' index of activities of daily living, the Physical...

  2. Short-Term Effects of Nose-Only Cigarette Smoke Exposure on Glutathione Redox Homeostasis, Cytochrome P450 1A1/2 and Respiratory Enzyme Activities in Mice Tissues

    Directory of Open Access Journals (Sweden)

    Haider Raza

    2013-05-01

    Full Text Available Background/Aims: The components of cigarette smoke (CS have been implicated in the development of cancer as well as in cardiopulmonary diseases. We have previously reported increased oxidative stress in rat tissues induced by tobacco-specific toxins nicotine and 4-(N-methyl-N-nitrosamino-1-(3-pyridyl-1-butanone (NNK. Recently, we have also shown increased oxidative stress and associated inflammatory responses in various tissues after exposure to cigarette smoke. Methods: In this study, we have further investigated the effects of nose-only cigarette smoke exposure on mitochondrial functions and glutathione-dependent redox metabolism in tissues of BALB/C mice. Liver, kidney, heart and lung tissues were analyzed for oxidative stress, glutathione (GSH and cytochrome P450 dependent enzyme activities and mitochondrial functions after exposure to smoke generated by 9 cigarettes/day for 4 days. Control mice were exposed to air only. Results: An increase in oxidative stress as observed by increased production of reactive oxygen species (ROS and altered GSH metabolism was apparent in all the tissues, but lung and heart appeared to be the main targets. Increased expression and activity of CYP450 1A1 and 1A2 were also observed in the tissues after exposure to cigarette smoke. Mitochondrial respiratory dysfunction in the tissues, as observed by alterations in the activities of Complex I and IV enzymes, was also observed after exposure to cigarette smoke. SDS-PAGE and Western blot results also indicate that alterations in the expression of enzyme proteins were in accordance with the changes in their catalytic functions. Conclusion: These results suggest that even short term exposure of cigarette smoke have adverse effects on mitochondrial functions and redox homeostasis in tissues which may progress to further complications associated with chronic smoking.

  3. Detection of Streptococcus suis by in situ hybridization, indirect immunofluorescence, and peroxidase-antiperoxidase assays in formalin-fixed, paraffin-embedded tissue sections from pigs

    DEFF Research Database (Denmark)

    Boye, Mette; Feenstra, Anne Avlund; Tegtmeier, Conny

    2000-01-01

    and the immunohistochemical methods were used for detection of S. suis in formalin-fixed, paraffin-embedded tissue sections of brain, endocardium, and lung from pigs infected with S. suis. The methods developed were able to detect single cells of S. suis in situ in the respective samples, whereas no signal was observed from...

  4. Actividad de glutatión peroxidasa en bovinos lecheros a pastoreo correlacionada con la concentración sanguinea y plasmática de selenio Blood activity of glutathione peroxidase and its correlation with blood selenium concentration in grazing dairy cattle

    Directory of Open Access Journals (Sweden)

    Alejandro Ceballos

    1999-12-01

    Full Text Available Con el objeto de validar una técnica para determinar la actividad sanguínea de glutatión peroxidasa (GSH-Px; EC 1.11.1.9 en el Laboratorio de Patología Clínica de la Universidad Austral de Chile y establecer la correlación entre su actividad y la concentración sanguínea y plasmática de selenio (Se en bovinos a pastoreo en rebaños lecheros del sur de Chile, se tomaron 5-10 mL de sangre heparinizada a 112 vacas de ocho rebaños en la provincia de Valdivia. La actividad enzimática se analizó mediante una técnica cinética, y el Se por activación de neutrones. Fueron calculadas la inexactitud e imprecisión de la técnica cinética y se describen el rango, promedio y desviación estándar de la actividad enzimática. La correlación entre la actividad sanguínea de GSH-Px y la concentración de Se fue obtenida mediante el coeficiente de correlación simple. La inexactitud e imprecisión fueron 5,9% y 10%, respectivamente. La actividad de GSH-Px fue 89 ± 45 U/g de hemoglobina (Hb y la correlación entre las variables señaladas fue r=0,97 (PSelenium (Se is part of the antioxidant enzyme glutathione peroxidase (GSH-Px; EC 1.11.1.9 structure, whose blood activity is related to the blood level of selenium. This study was designed to validate the analytical method to analyze the GSH-Px blood activity at the Clinical Pathology Laboratory of the Universidad Austral de Chile, and to correlate it with blood Se level in dairy cattle from the South of Chile. Blood heparinized samples were taken from 112 dairy cows from eight dairy herds located at Valdivia province, Chile. A kinetic NADPH-dependent technique was used to analyze the blood GSH-Px, and the content of Se in blood and plasma was analyzed by neutron activation. The Se concentration in blood was analyzed in 12 samples to correlate GSH-Px blood activity with blood and plasma Se level. The inaccuracy and imprecision were 5.9% and 10%, respectively. The mean and standard deviation of the

  5. Oxidative stress and antioxidant activity in orbital fibroadipose tissue in Graves' ophthalmopathy.

    Science.gov (United States)

    Hondur, Ahmet; Konuk, Onur; Dincel, Aylin Sepici; Bilgihan, Ayse; Unal, Mehmet; Hasanreisoglu, Berati

    2008-05-01

    To investigate the oxidative stress and antioxidant activity in the orbit in Graves' ophthalmopathy (GO). Orbital fibroadipose tissue samples were obtained from 13 cases during orbital fat decompression surgery. All cases demonstrated features of moderate or severe GO according to the European Group on Graves' Orbitopathy classification. The disease activity was evaluated with the Clinical Activity Score, and the clinical features of GO were evaluated with the Ophthalmopathy Index. Orbital fibroadipose tissue samples of 8 patients without any thyroid or autoimmune disease were studied as controls. In the tissue samples, lipid hydroperoxide level was examined to determine the level of oxidative stress; glutathione level to determine antioxidant level; superoxide dismutase, glutathione reductase, and glutathione peroxidase activities to determine antioxidant activity. Lipid hydroperoxide level and all three antioxidant enzyme activities were found to be significantly elevated, while glutathione level significantly diminished in tissue samples from GO cases compared to controls (p < 0.05). Glutathione levels in tissue samples of GO cases showed negative correlation with Ophthalmopathy Index (r = -0.59, p < 0.05). The antioxidant activity in the orbit is enhanced in GO. However, the oxidative stress appears to be severe enough to deplete the tissue antioxidants and leads to oxidative tissue damage. This study may support the possible value of antioxidant treatment in GO.

  6. Oxidation of eugenol by purified human term placental peroxidase.

    Science.gov (United States)

    Zhang, R; Kulkarni, K A; Kulkarni, A P

    2000-01-01

    The oxidation of eugenol by purified human term placental peroxidase (HTPP) was examined. Spectral analyses indicated that, similar to horseradish peroxidase, HTPP is capable of catalyzing the oxidation of eugenol. The accumulated stable product in the reaction medium due to eugenol oxidation by HTPP was tentatively identified as quinone methide of eugenol (EQM). The EQM formation exhibited a pH optimum of 8.0 and was dependent on incubation time, amount of HTPP and the concentration of both eugenol and hydrogen peroxide. The specific activity of approx 2.8 micromoles of EQM/min/mg protein was observed with different preparations of HTPP. The EQM formation was significantly suppressed by glutathione and ascorbic acid. The classical peroxidase inhibitors viz. potassium cyanide and sodium azide blocked the reaction in a concentration manner. Collectively, the results suggest that eugenol may undergo peroxidative metabolism in human placenta. Copyright 2000 Harcourt Publishers Ltd.

  7. The Effects on Antioxidant Enzyme Systems in Rat Brain Tissues of Lead Nitrate and Mercury Chloride

    OpenAIRE

    Baş, Hatice; Kalender, Suna; Karaboduk, Hatice; Apaydın, Fatma

    2014-01-01

    The present study was undertaken to evaluate the effects of lead nitrate and mercury chloride in brain tissues of Wistar rats. Mercury chloride (0.02 mg/kg bw) and lead nitrate (45 mg/kg bw) were administered orally for 28 days rats. The mercury chloride and lead nitrate treated animals were exhibited a significant inhibition of superoxide dismutase, catalase, glutation peroxidase and glutathione-S-transferase activities and increasing of malondialdehyde levels. In our present study mercury c...

  8. Expression Patterns of Genes Involved in Ascorbate-Glutathione Cycle in Aphid-Infested Maize (Zea mays L.) Seedlings.

    Science.gov (United States)

    Sytykiewicz, Hubert

    2016-02-23

    Reduced forms of ascorbate (AsA) and glutathione (GSH) are among the most important non-enzymatic foliar antioxidants in maize (Zea mays L.). The survey was aimed to evaluate impact of bird cherry-oat aphid (Rhopalosiphum padi L.) or grain aphid (Sitobion avenae F.) herbivory on expression of genes related to ascorbate-glutathione (AsA-GSH) cycle in seedlings of six maize varieties (Ambrozja, Nana, Tasty Sweet, Touran, Waza, Złota Karłowa), differing in resistance to the cereal aphids. Relative expression of sixteen maize genes encoding isoenzymes of ascorbate peroxidase (APX1, APX2, APX3, APX4, APX5, APX6, APX7), monodehydroascorbate reductase (MDHAR1, MDHAR2, MDHAR3, MDHAR4), dehydroascorbate reductase (DHAR1, DHAR2, DHAR3) and glutathione reductase (GR1, GR2) was quantified. Furthermore, effect of hemipterans' attack on activity of APX, MDHAR, DHAR and GR enzymes, and the content of reduced and oxidized ascorbate and glutathione in maize plants were assessed. Seedling leaves of more resistant Z. mays varieties responded higher elevations in abundance of target transcripts. In addition, earlier and stronger aphid-triggered changes in activity of APX, MDHAR, DHAR and GR enzymes, and greater modulations in amount of the analyzed antioxidative metabolites were detected in foliar tissues of highly resistant Ambrozja genotype in relation to susceptible Tasty Sweet plants.

  9. Incorporation of carbohydrate residues into peroxidase isoenzymes in horseradish roots.

    Science.gov (United States)

    Lew, J Y; Shannon, L M

    1973-11-01

    Sliced root tissue of the horseradish plant (Armoracia rusticana), when incubated with mannose-U-(14)C, incorporated radioactivity into peroxidase isoenzymes. Over 90% of the radioactivity in the highly purified peroxidase isoenzymes was present in the neutral sugar residues of the molecule, i.e. fucose, arabinose, xylose, mannose. When the root slices were incubated simultaneously with leucine-4,5-(3)H and mannose-U-(14)C, cycloheximide strongly inhibited leucine incorporation into the peptide portion of peroxidase isoenzymes but had little effect on the incorporation of (14)C into the neutral sugars. These results indicated that synthesis of the peptide portion of peroxidase was completed before the monosaccharide residues were attached to the molecule. This temporal relationship between the synthesis of protein and the attachment of carbohydrate residues in the plant glycoprotein, horseradish peroxidase, appears to be similar to that reported for glycoprotein biosynthesis in many mammalian systems.

  10. The antioxidant master glutathione and periodontal health

    Directory of Open Access Journals (Sweden)

    Vivek Kumar Bains

    2015-01-01

    Full Text Available Glutathione, considered to be the master antioxidant (AO, is the most-important redox regulator that controls inflammatory processes, and thus damage to the periodontium. Periodontitis patients have reduced total AO capacity in whole saliva, and lower concentrations of reduced glutathione (GSH in serum and gingival crevicular fluid, and periodontal therapy restores the redox balance. Therapeutic considerations for the adjunctive use of glutathione in management of periodontitis, in limiting the tissue damage associated with oxidative stress, and enhancing wound healing cannot be underestimated, but need to be evaluated further through multi-centered randomized controlled trials.

  11. Glutathione system in Wolfram syndrome 1‑deficient mice.

    Science.gov (United States)

    Porosk, Rando; Kilk, Kalle; Mahlapuu, Riina; Terasmaa, Anton; Soomets, Ursel

    2017-11-01

    Wolfram syndrome 1 (WS) is a rare neurodegenerative disease that is caused by mutations in the Wolfram syndrome 1 (WFS1) gene, which encodes the endoplasmic reticulum (ER) glycoprotein wolframin. The pathophysiology of WS is ER stress, which is generally considered to induce oxidative stress. As WS has a well‑defined monogenetic origin and a model for chronic ER stress, the present study aimed to characterize how glutathione (GSH), a major intracellular antioxidant, was related to the disease and its progression. The concentration of GSH and the activities of reduction/oxidation system enzymes GSH peroxidase and GSH reductase were measured in Wfs1‑deficient mice. The GSH content was lower in most of the studied tissues, and the activities of antioxidative enzymes varied between the heart, kidneys and liver tissues. The results indicated that GSH may be needed for ER stress control; however, chronic ER stress from the genetic syndrome eventually depletes the cellular GSH pool and leads to increased oxidative stress.

  12. Role of glutathione in tolerance to arsenite in Salvinia molesta, an aquatic fern

    Directory of Open Access Journals (Sweden)

    Adinan Alves da Silva

    2017-09-01

    Full Text Available ABSTRACT In many plant species, tolerance to toxic metals is highly dependent on glutathione, an essential metabolite for cellular detoxification. We evaluated the responses of glutathione metabolism to arsenite (AsIII in Salvinia molesta, an aquatic fern that has unexplored phytoremediation potential. Plants were exposed to different AsIII concentrations in nutrient solution for 24 h. AsIII caused cell membrane damage to submerged leaves, indicating oxidative stress. There was an increase in the glutathione content and ϒ-glutamylcysteine synthetase enzyme activity in the submerged and floating leaves. The glutathione peroxidase and glutathione sulfotransferase enzymes also showed increased activity in both plant parts, whereas glutathione reductase only showed increased activity in the submerged leaves. These findings suggest an important role for glutathione in the protection of S. molesta against the toxic effects of AsIII, with more effective tolerance responses in the floating leaves.

  13. Effects of methylmercury exposure on glutathione metabolism, oxidative stress, and chromosomal damage in captive-reared common loon (Gavia immer) chicks

    International Nuclear Information System (INIS)

    Kenow, Kevin P.; Hoffman, David J.; Hines, Randy K.; Meyer, Michael W.; Bickham, John W.; Matson, Cole W.; Stebbins, Katie R.; Montagna, Paul; Elfessi, Abdulaziz

    2008-01-01

    We quantified the level of dietary mercury (Hg), delivered as methylmercury chloride (CH 3 HgCl), associated with negative effects on organ and plasma biochemistries related to glutathione (GSH) metabolism and oxidative stress, and chromosomal damage in captive-reared common loon (Gavia immer) chicks reared from hatch to 105 days. Mercury-associated effects related to oxidative stress and altered glutathione metabolism occurred at 1.2 μg Hg/g and 0.4 μg Hg/g, an ecologically relevant dietary mercury level, but not at 0.08 μg Hg/g. Among the variables that contributed most to dissimilarities in tissue chemistries between control and treatment groups were increased levels of oxidized glutathione (GSSG), GSH peroxidase, and the ratio of GSSG to GSH in brain tissue; increased levels of hepatic GSH; and decreased levels of hepatic glucose-6-phosphate dehydrogenase (G-6-PDH). Our results also suggest that chronic exposure to environmentally relevant dietary Hg levels did not result in statistically significant somatic chromosomal damage in common loon chicks. - Oxidative stress and altered glutathione metabolism were evident in common loon chicks exposed to ≥0.4 μg Hg as CH 3 HgCl per gram wet food intake

  14. Effects of methylmercury exposure on glutathione metabolism, oxidative stress, and chromosomal damage in captive-reared common loon (Gavia immer) chicks

    Energy Technology Data Exchange (ETDEWEB)

    Kenow, Kevin P. [U.S. Geological Survey, Upper Midwest Environmental Sciences Center, 2630 Fanta Reed Road, La Crosse, WI 54603 (United States)], E-mail: kkenow@usgs.gov; Hoffman, David J. [U.S. Geological Survey, Patuxent Wildlife Research Center, 10300 Baltimore Avenue, Beltsville, MD 20705 (United States)], E-mail: djhoffman@usgs.gov; Hines, Randy K. [U.S. Geological Survey, Upper Midwest Environmental Sciences Center, 2630 Fanta Reed Road, La Crosse, WI 54603 (United States)], E-mail: rkhines@usgs.gov; Meyer, Michael W. [Wisconsin Department of Natural Resources, 107 Sutliff Avenue, Rhinelander, WI 54501 (United States)], E-mail: michael.meyer@dnr.state.wi.us; Bickham, John W. [Center for the Environment and Department of Forestry and Natural Resources, Purdue University, West Lafayette, IN 47907 (United States)], E-mail: bickham@purdue.edu; Matson, Cole W. [Integrated Toxicology and Environmental Health Program, Duke University, Durham, NC 27708 (United States)], E-mail: matson@duke.edu; Stebbins, Katie R. [U.S. Geological Survey, Patuxent Wildlife Research Center, 10300 Baltimore Avenue, Beltsville, MD 20705 (United States); Montagna, Paul [Texas A and M University-Corpus Christi, Harte Research Institute, Corpus Christi, TX (United States)], E-mail: paul.montagna@tamucc.edu; Elfessi, Abdulaziz [University of Wisconsin-La Crosse, La Crosse, WI 54601 (United States)], E-mail: elfessi.abdu@uwlax.edu

    2008-12-15

    We quantified the level of dietary mercury (Hg), delivered as methylmercury chloride (CH{sub 3}HgCl), associated with negative effects on organ and plasma biochemistries related to glutathione (GSH) metabolism and oxidative stress, and chromosomal damage in captive-reared common loon (Gavia immer) chicks reared from hatch to 105 days. Mercury-associated effects related to oxidative stress and altered glutathione metabolism occurred at 1.2 {mu}g Hg/g and 0.4 {mu}g Hg/g, an ecologically relevant dietary mercury level, but not at 0.08 {mu}g Hg/g. Among the variables that contributed most to dissimilarities in tissue chemistries between control and treatment groups were increased levels of oxidized glutathione (GSSG), GSH peroxidase, and the ratio of GSSG to GSH in brain tissue; increased levels of hepatic GSH; and decreased levels of hepatic glucose-6-phosphate dehydrogenase (G-6-PDH). Our results also suggest that chronic exposure to environmentally relevant dietary Hg levels did not result in statistically significant somatic chromosomal damage in common loon chicks. - Oxidative stress and altered glutathione metabolism were evident in common loon chicks exposed to {>=}0.4 {mu}g Hg as CH{sub 3}HgCl per gram wet food intake.

  15. Blood selenium concentrations and enzyme activities related to glutathione metabolism in wild emperor geese

    Science.gov (United States)

    Franson, J. Christian; Hoffman, David J.; Schmutz, Joel A.

    2002-01-01

    In 1998, we collected blood samples from 63 emperor geese (Chen canagica) on their breeding grounds on the Yukon-Kuskokwim Delta (YKD) in western Alaska, USA. We studied the relationship between selenium concentrations in whole blood and the activities of glutathione peroxidase and glutathione reductase in plasma. Experimental studies have shown that plasma activities of these enzymes are useful biomarkers of selenium-induced oxidative stress, but little information is available on their relationship to selenium in the blood of wild birds. Adult female emperor geese incubating their eggs in mid-June had a higher mean concentration of selenium in their blood and a greater activity of glutathione peroxidase in their plasma than adult geese or goslings that were sampled during the adult flight feathermolting period in late July and early August. Glutathione peroxidase activity was positively correlated with the concentration of selenium in the blood of emperor geese, and the rate of increase relative to selenium was greater in goslings than in adults. The activity of glutathione reductase was greatest in the plasma of goslings and was greater in molting adults than incubating females but was not significantly correlated with selenium in the blood of adults or goslings. Incubating female emperor geese had high selenium concentrations in their blood, accompanied by increased glutathione peroxidase activity consistent with early oxidative stress. These findings indicate that further study of the effects of selenium exposure, particularly on reproductive success, is warranted in this species.

  16. Protection of myocytes against free radical-induced damage by accelerated turnover of the glutathione redox cycle

    NARCIS (Netherlands)

    Le, C. T.; Hollaar, L.; van der Valk, E. J.; Franken, N. A.; van Ravels, F. J.; Wondergem, J.; van der Laarse, A.

    1995-01-01

    The primary defence mechanism of myocytes against peroxides and peroxide-derived peroxyl and alkoxyl radicals is the glutathione redox cycle. The purpose of the present study was to increase the turnover rate of this cycle by stimulating the glutathione peroxidase catalysed reaction (2GSH-->GSSG),

  17. Glutathione content in sperm cells of infertile men

    Directory of Open Access Journals (Sweden)

    R. V. Fafula

    2017-04-01

    Full Text Available Hyperproduction of reactive oxygen species can damage sperm cells and is considered to be one of the mechanisms of male infertility. Cell protection from the damaging effects of free radicals and lipid peroxidation products is generally determined by the degree of antioxidant protection. Glutathione is non-enzymatic antioxidant which plays an important protective role against oxidative damages and lipid peroxidation. The aim of the present work is to determine the content of reduced and oxidized glutathione in sperm cells of infertile men. Semen samples from 20 fertile men (normozoospermics and 72 infertile patients (12 oligozoospermics, 17 asthenozoospermics, 10 oligoasthenozoosper­mics and 33 leucocytospermic were used. The total, oxidized (GSSG and reduced (GSH glutathione levels were measured spectrophotometrically. The levels of total glutathione were significantly lower in the spermatozoa of patients with oligozoo-, asthenozoo- and oligoasthenozoospermia than in the control. Infertile groups showed significantly decreased values of reduced glutathione in sperm cells vs. fertile men, indicating an alteration of oxidative status. The oxidized glutathione levels in sperm cells of infertile men did not differ from those of normozoospermic men with proven fertility. The GSH/GSSG ratio was significantly decreased in the oligo-, astheno- and oligoasthenozoospermic groups compared to the normozoospermic group. In patients with leucocytospermia the GSH/GSSG ratio was lower but these changes were not significant. In addition, glutathione peroxidase activity in sperm cells was decreased in patients with oligozoo-, astenozoo-, oligoastenozoospermia and with leucocytospermia. The most significant changes in glutathione peroxidase activity were observed in infertile men with leucocytospermia. Decreased GSH/GSSG ratio indicates a decline in redox-potential of the glutathione system in sperm cells of men with decreased fertilizing potential

  18. Glutathione level after long-term occupational elemental mercury exposure

    International Nuclear Information System (INIS)

    Kobal, Alfred Bogomir; Prezelj, Marija; Horvat, Milena; Krsnik, Mladen; Gibicar, Darija; Osredkar, Josko

    2008-01-01

    Many in vitro and in vivo studies have elucidated the interaction of inorganic mercury (Hg) and glutathione. However, human studies are limited. In this study, we investigated the potential effects of remote long-term intermittent occupational elemental Hg vapour (Hg o ) exposure on erythrocyte glutathione levels and some antioxidative enzyme activities in ex-mercury miners in the period after exposure. The study included 49 ex-mercury miners divided into subgroups of 28 still active, Hg o -not-exposed miners and 21 elderly retired miners, and 41 controls, age-matched to the miners subgroup. The control workers were taken from 'mercury-free works'. Reduced glutathione (GSH) and oxidized disulphide glutathione (GSSG) concentrations in haemolysed erythrocytes were determined by capillary electrophoresis, while total glutathione (total GSH) and the GSH/GSSG ratio were calculated from the determined values. Catalase (CAT), glutathione peroxidase (GPx), and glutathione reductase (GR) activities in erythrocytes were measured using commercially available reagent kits, while urine Hg (U-Hg) concentrations were determined by cold vapour atomic absorption (CVAAS). No correlation of present U-Hg levels, GSH, GSSG, and antioxidative enzymes with remote occupational biological exposure indices were found. The mean CAT activity in miners and retired miners was significantly higher (p o could be an inductive and additive response to maintain the balance between GSH and antioxidative enzymes in interaction with the Hg body burden accumulated during remote occupational exposure, which does not represent a severely increased oxidative stress

  19. Single-bilayer graphene oxide sheet tolerance and glutathione redox system significance assessment in faba bean (Vicia faba L.)

    International Nuclear Information System (INIS)

    Anjum, Naser A.; Singh, Neetu; Singh, Manoj K.; Shah, Zahoor A.; Duarte, Armando C.; Pereira, Eduarda; Ahmad, Iqbal

    2013-01-01

    Adsorbents based on single-bilayer graphene oxide sheet (hereafter termed “graphene oxide”) are widely used in contaminated environments cleanup which may easily open the avenues for their entry to different environmental compartments, exposure to organisms and their subsequent transfer to human/animal food chain. Considering a common food crop—faba bean (Vicia faba L.) germinating seedlings as a model plant system, this study assesses the V. faba-tolerance to different concentrations (0, 100, 200, 400, 800, and 1600 mg L −1 ) of graphene oxide (0.5–5 μm) and evaluates glutathione (γ-glutamyl-cysteinyl-glycine) redox system significance in this context. The results showed significantly increased V. faba sensitivity under three graphene oxide concentrations (in order of impact: 1,600 > 200 > 100 mg graphene oxide L −1 ), which was accompanied by decreased glutathione redox (reduced glutathione-to-oxidized glutathione) ratio, reduced glutathione pool, as well as significant and equally elevated activities of glutathione-regenerating (glutathione reductase) and glutathione-metabolizing (glutathione peroxidase; glutathione sulfo-transferase) enzymes. Contrarily, the two graphene oxide concentrations (in order of impact: 800 > 400 graphene oxide mg L −1 ) yielded promising results; where, significant improvements in V. faba health status (measured as increased graphene oxide tolerance) were clearly perceptible with increased ratio of the reduced glutathione-to-oxidized glutathione, reduced glutathione pool and glutathione reductase activity but decreased activities of glutathione-metabolizing enzymes. It is inferred that V. faba seedlings-sensitivity and/or tolerance to graphene oxide concentrations depends on both the cellular redox state (reduced glutathione-to-oxidized glutathione ratio) and the reduced glutathione pool which in turn are controlled by a finely tuned modulation of the coordination between glutathione-regenerating and glutathione

  20. Single-bilayer graphene oxide sheet tolerance and glutathione redox system significance assessment in faba bean (Vicia faba L.)

    Energy Technology Data Exchange (ETDEWEB)

    Anjum, Naser A. [University of Aveiro, Centre for Environmental and Marine Studies (CESAM) and Department of Chemistry (Portugal); Singh, Neetu; Singh, Manoj K. [University of Aveiro, Center for Mechanical Technology and Automation (TEMA) and Department of Mechanical Engineering (Portugal); Shah, Zahoor A. [University of Toledo, Department of Medicinal and Biological Chemistry, College of Pharmacy and Pharmaceutical Sciences (United States); Duarte, Armando C.; Pereira, Eduarda; Ahmad, Iqbal, E-mail: ahmadr@ua.pt [University of Aveiro, Centre for Environmental and Marine Studies (CESAM) and Department of Chemistry (Portugal)

    2013-07-15

    Adsorbents based on single-bilayer graphene oxide sheet (hereafter termed 'graphene oxide') are widely used in contaminated environments cleanup which may easily open the avenues for their entry to different environmental compartments, exposure to organisms and their subsequent transfer to human/animal food chain. Considering a common food crop-faba bean (Vicia faba L.) germinating seedlings as a model plant system, this study assesses the V. faba-tolerance to different concentrations (0, 100, 200, 400, 800, and 1600 mg L{sup -1}) of graphene oxide (0.5-5 {mu}m) and evaluates glutathione ({gamma}-glutamyl-cysteinyl-glycine) redox system significance in this context. The results showed significantly increased V. faba sensitivity under three graphene oxide concentrations (in order of impact: 1,600 > 200 > 100 mg graphene oxide L{sup -1}), which was accompanied by decreased glutathione redox (reduced glutathione-to-oxidized glutathione) ratio, reduced glutathione pool, as well as significant and equally elevated activities of glutathione-regenerating (glutathione reductase) and glutathione-metabolizing (glutathione peroxidase; glutathione sulfo-transferase) enzymes. Contrarily, the two graphene oxide concentrations (in order of impact: 800 > 400 graphene oxide mg L{sup -1}) yielded promising results; where, significant improvements in V. faba health status (measured as increased graphene oxide tolerance) were clearly perceptible with increased ratio of the reduced glutathione-to-oxidized glutathione, reduced glutathione pool and glutathione reductase activity but decreased activities of glutathione-metabolizing enzymes. It is inferred that V. faba seedlings-sensitivity and/or tolerance to graphene oxide concentrations depends on both the cellular redox state (reduced glutathione-to-oxidized glutathione ratio) and the reduced glutathione pool which in turn are controlled by a finely tuned modulation of the coordination between glutathione-regenerating and

  1. Dietary Supplementation with the Microalga Galdieria sulphuraria (Rhodophyta Reduces Prolonged Exercise-Induced Oxidative Stress in Rat Tissues

    Directory of Open Access Journals (Sweden)

    Simona Carfagna

    2015-01-01

    Full Text Available We studied the effects of ten-day 1% Galdieria sulphuraria dietary supplementation on oxidative damage and metabolic changes elicited by acute exercise (6-hour swimming determining oxygen consumption, lipid hydroperoxides, protein bound carbonyls in rat tissue (liver, heart, and muscle homogenates and mitochondria, tissue glutathione peroxidase and glutathione reductase activities, glutathione content, and rates of H2O2 mitochondrial release. Exercise increased oxidative damage in tissues and mitochondria and decreased tissue content of reduced glutathione. Moreover, it increased State 4 and decreased State 3 respiration in tissues and mitochondria. G. sulphuraria supplementation reduced the above exercise-induced variations. Conversely, alga supplementation was not able to modify the exercise-induced increase in mitochondrial release rate of hydrogen peroxide and in liver and heart antioxidant enzyme activities. The alga capacity to reduce lipid oxidative damage without reducing mitochondrial H2O2 release can be due to its high content of C-phycocyanin and glutathione, which are able to scavenge peroxyl radicals and contribute to phospholipid hydroperoxide metabolism, respectively. In conclusion, G. sulphuraria ability to reduce exercise-linked oxidative damage and mitochondrial dysfunction makes it potentially useful even in other conditions leading to oxidative stress, including hyperthyroidism, chronic inflammation, and ischemia/reperfusion.

  2. Dietary supplementation with the microalga Galdieria sulphuraria (Rhodophyta) reduces prolonged exercise-induced oxidative stress in rat tissues.

    Science.gov (United States)

    Carfagna, Simona; Napolitano, Gaetana; Barone, Daniela; Pinto, Gabriele; Pollio, Antonino; Venditti, Paola

    2015-01-01

    We studied the effects of ten-day 1% Galdieria sulphuraria dietary supplementation on oxidative damage and metabolic changes elicited by acute exercise (6-hour swimming) determining oxygen consumption, lipid hydroperoxides, protein bound carbonyls in rat tissue (liver, heart, and muscle) homogenates and mitochondria, tissue glutathione peroxidase and glutathione reductase activities, glutathione content, and rates of H2O2 mitochondrial release. Exercise increased oxidative damage in tissues and mitochondria and decreased tissue content of reduced glutathione. Moreover, it increased State 4 and decreased State 3 respiration in tissues and mitochondria. G. sulphuraria supplementation reduced the above exercise-induced variations. Conversely, alga supplementation was not able to modify the exercise-induced increase in mitochondrial release rate of hydrogen peroxide and in liver and heart antioxidant enzyme activities. The alga capacity to reduce lipid oxidative damage without reducing mitochondrial H2O2 release can be due to its high content of C-phycocyanin and glutathione, which are able to scavenge peroxyl radicals and contribute to phospholipid hydroperoxide metabolism, respectively. In conclusion, G. sulphuraria ability to reduce exercise-linked oxidative damage and mitochondrial dysfunction makes it potentially useful even in other conditions leading to oxidative stress, including hyperthyroidism, chronic inflammation, and ischemia/reperfusion.

  3. [The activity of glutathione antioxidant system at melaksen and valdoxan action under experimental hyperthyroidism in rats].

    Science.gov (United States)

    Gorbenko, M V; Popova, T N; Shul'gin, K K; Popov, S S

    2013-01-01

    Investigation of glutathione antioxidant system activity and diene conjugates content in rats liver and blood serum at the influence of melaksen and valdoxan under experimental hyperthyroidism (EG) has been revealed. It has been established that the activities of glutathione reductase (GR), glutathione peroxidase (GP) and glutathione transferase (GT), growing at pathological conditions, change to the side of control value at these substunces introduction. Reduced glutathione content (GSH) at melaxen and valdoxan action increased compared with values under the pathology, that, obviously, could be associated with a reduction of its spending on the detoxication of free radical oxidation (FRO) toxic products. Diene conjugates level in rats liver and blood serum, increasing at experimental hyperthyroidism conditions, under introduction of melatonin level correcting drugs, also approached to the control meaning. Results of the study indicate on positive effect of melaxen and valdoxan on free radical homeostasis, that appears to be accompanied by decrease of load on the glutathione antioxidant system in comparison with the pathology.

  4. Membrane accessibility of glutathione

    DEFF Research Database (Denmark)

    Garcia, Almudena; Eljack, N., D.; Sani, ND

    2015-01-01

    Regulation of the ion pumping activity of the Na(+),K(+)-ATPase is crucial to the survival of animal cells. Recent evidence has suggested that the activity of the enzyme could be controlled by glutathionylation of cysteine residue 45 of the β-subunit. Crystal structures so far available indicate...... that this cysteine is in a transmembrane domain of the protein. Here we have analysed via fluorescence and NMR spectroscopy as well as molecular dynamics simulations whether glutathione is able to penetrate into the interior of a lipid membrane. No evidence for any penetration of glutathione into the membrane...

  5. Uranyl complexes of glutathione

    Energy Technology Data Exchange (ETDEWEB)

    Marzotto, A [Consiglio Nazionale delle Ricerche, Padua (Italy). Lab. di Chimica e Tecnologia dei Radioelementi

    1977-01-01

    Dioxouranium(VI) complexes of the tripeptide glutathione having different molar ratios were prepared and studied by IR, PMR, electronic absorption and circular dichroism spectra. The results indicate that coordination occurs at the carboxylato groups, acting as monodentate ligands, whereas no significant interaction with the amino and sulfhydrylic groups takes place.

  6. Expression, purification and characterization of a peroxidase from ...

    African Journals Online (AJOL)

    Yomi

    2012-01-24

    Jan 24, 2012 ... from a cDNA library, which was generated from root tissue of Tamarix hispida that was exposed to ... enzymes, peroxidase (POD) plays an important role in .... ThPOD1 protein under various conditions, 3 month old T. hispida.

  7. Characterization of glutathione transferases involved in the pathogenicity of Alternaria brassicicola.

    Science.gov (United States)

    Calmes, Benoit; Morel-Rouhier, Mélanie; Bataillé-Simoneau, Nelly; Gelhaye, Eric; Guillemette, Thomas; Simoneau, Philippe

    2015-06-18

    Glutathione transferases (GSTs) represent an extended family of multifunctional proteins involved in detoxification processes and tolerance to oxidative stress. We thus anticipated that some GSTs could play an essential role in the protection of fungal necrotrophs against plant-derived toxic metabolites and reactive oxygen species that accumulate at the host-pathogen interface during infection. Mining the genome of the necrotrophic Brassica pathogen Alternaria brassicicola for glutathione transferase revealed 23 sequences, 17 of which could be clustered into the main classes previously defined for fungal GSTs and six were 'orphans'. Five isothiocyanate-inducible GSTs from five different classes were more thoroughly investigated. Analysis of their catalytic properties revealed that two GSTs, belonging to the GSTFuA and GTT1 classes, exhibited GSH transferase activity with isothiocyanates (ITC) and peroxidase activity with cumene hydroperoxide, respectively. Mutant deficient for these two GSTs were however neither more susceptible to ITC nor less aggressive than the wild-type parental strain. By contrast mutants deficient for two other GSTs, belonging to the Ure2pB and GSTO classes, were distinguished by their hyper-susceptibility to ITC and low aggressiveness against Brassica oleracea. In particular AbGSTO1 could participate in cell tolerance to ITC due to its glutathione-dependent thioltransferase activity. The fifth ITC-inducible GST belonged to the MAPEG class and although it was not possible to produce the soluble active form of this protein in a bacterial expression system, the corresponding deficient mutant failed to develop normal symptoms on host plant tissues. Among the five ITC-inducible GSTs analyzed in this study, three were found essential for full aggressiveness of A. brassicicola on host plant. This, to our knowledge is the first evidence that GSTs might be essential virulence factors for fungal necrotrophs.

  8. Peroxidase synthesis and activity in the interaction of soybean with Phytophthora megasperma f. sp. glycinea (Pmg)

    International Nuclear Information System (INIS)

    Chibbar, R.N.; Esnault, R.; Lee, D.; van Huystee, R.B.; Ward, E.W.B.

    1986-01-01

    Changes, in peroxidase (EC1.11.1.7) have been reported following infection. However, determinations of biosynthesis of quantities of the peroxidase protein molecule have not been made! In this study hypocotyl of soybean seedlings (Glycine max; cv Harosoy, susceptible; cv Harosoy 63, resistant) were inoculated with zoospores of Pmg. Incorporation of 35 S-methionine (supplied with inoculum) in TCA precipitates was measured. Peroxidase synthesis was measured by immuno precipitation using antibodies against a cationic and an anionic peroxidase derived from peanut cells. Specific peroxidase activity increased rapidly from 5 to 9 h following infection in the resistant reaction but not in the susceptible reaction or the water controls. There was increased synthesis of the anionic peroxidase but not of the cationic peroxidase in the resistant reaction. The anionic peroxidase did not increase in the susceptible until 15 h. The ratio of peroxidase synthesis to total protein synthesis decreased in inoculated tissues compared to control. Peroxidase synthesis is, therefore, a relative minor host response to infection

  9. Glutathione-S-transferase-omega [MMA(V) reductase] knockout mice: Enzyme and arsenic species concentrations in tissues after arsenate administration

    International Nuclear Information System (INIS)

    Chowdhury, Uttam K.; Zakharyan, Robert A.; Hernandez, Alba; Avram, Mihaela D.; Kopplin, Michael J.; Aposhian, H. Vasken

    2006-01-01

    Inorganic arsenic is a human carcinogen to which millions of people are exposed via their naturally contaminated drinking water. Its molecular mechanisms of carcinogenicity have remained an enigma, perhaps because arsenate is biochemically transformed to at least five other arsenic-containing metabolites. In the biotransformation of inorganic arsenic, GSTO1 catalyzes the reduction of arsenate, MMA(V), and DMA(V) to the more toxic + 3 arsenic species. MMA(V) reductase and human (hGSTO1-1) are identical proteins. The hypothesis that GST-Omega knockout mice biotransformed inorganic arsenic differently than wild-type mice has been tested. The livers of male knockout (KO) mice, in which 222 bp of Exon 3 of the GSTO1 gene were eliminated, were analyzed by PCR for mRNA. The level of transcripts of the GSTO1 gene in KO mice was 3.3-fold less than in DBA/1lacJ wild-type (WT) mice. The GSTO2 transcripts were about two-fold less in the KO mouse. When KO and WT mice were injected intramuscularly with Na arsenate (4.16 mg As/kg body weight); tissues removed at 0.5, 1, 2, 4, 8, and 12 h after arsenate injection; and the arsenic species measured by HPLC-ICP-MS, the results indicated that the highest concentration of the recently discovered and very toxic MMA(III), a key biotransformant, was in the kidneys of both KO and WT mice. The highest concentration of DMA(III) was in the urinary bladder tissue for both the KO and WT mice. The MMA(V) reducing activity of the liver cytosol of KO mice was only 20% of that found in wild-type mice. There appears to be another enzyme(s) other than GST-O able to reduce arsenic(V) species but to a lesser extent. This and other studies suggest that each step of the biotransformation of inorganic arsenic has an alternative enzyme to biotransform the arsenic substrate

  10. Impaired synthesis and antioxidant defense of glutathione in the cerebellum of autistic subjects: alterations in the activities and protein expression of glutathione-related enzymes.

    Science.gov (United States)

    Gu, Feng; Chauhan, Ved; Chauhan, Abha

    2013-12-01

    Autism is a neurodevelopmental disorder associated with social deficits and behavioral abnormalities. Recent evidence in autism suggests a deficit in glutathione (GSH), a major endogenous antioxidant. It is not known whether the synthesis, consumption, and/or regeneration of GSH is affected in autism. In the cerebellum tissues from autism (n=10) and age-matched control subjects (n=10), the activities of GSH-related enzymes glutathione peroxidase (GPx), glutathione-S-transferase (GST), glutathione reductase (GR), and glutamate cysteine ligase (GCL) involved in antioxidant defense, detoxification, GSH regeneration, and synthesis, respectively, were analyzed. GCL is a rate-limiting enzyme for GSH synthesis, and the relationship between its activity and the protein expression of its catalytic subunit GCLC and its modulatory subunit GCLM was also compared between the autistic and the control groups. Results showed that the activities of GPx and GST were significantly decreased in autism compared to that of the control group (Pautistic subjects showed lower GR activity than 95% confidence interval (CI) of the control group. GCL activity was also significantly reduced by 38.7% in the autistic group compared to the control group (P=0.023), and 8 of 10 autistic subjects had values below 95% CI of the control group. The ratio of protein levels of GCLC to GCLM in the autism group was significantly higher than that of the control group (P=0.022), and GCLM protein levels were reduced by 37.3% in the autistic group compared to the control group. A positive strong correlation was observed between GCL activity and protein levels of GCLM (r=0.887) and GCLC (r=0.799) subunits in control subjects but not in autistic subjects, suggesting that regulation of GCL activity is affected in autism. These results suggest that enzymes involved in GSH homeostasis have impaired activities in the cerebellum in autism, and lower GCL activity in autism may be related to decreased protein expression

  11. Oxidation of NAD dimers by horseradish peroxidase.

    OpenAIRE

    Avigliano, L; Carelli, V; Casini, A; Finazzi-Agrò, A; Liberatore, F

    1985-01-01

    Horseradish peroxidase catalyses the oxidation of NAD dimers, (NAD)2, to NAD+ in accordance with a reaction that is pH-dependent and requires 1 mol of O2 per 2 mol of (NAD)2. Horseradish peroxidase also catalyses the peroxidation of (NAD)2 to NAD+. In contrast, bacterial NADH peroxidase does not catalyse the peroxidation or the oxidation of (NAD)2. A free-radical mechanism is proposed for both horseradish-peroxidase-catalysed oxidation and peroxidation of (NAD)2.

  12. Arabidopsis ATP A2 peroxidase. Expression and high-resolution structure of a plant peroxidase with implications for lignification

    DEFF Research Database (Denmark)

    Ostergaard, L; Teilum, K; Mirza, O

    2000-01-01

    Lignins are phenolic biopolymers synthesized by terrestrial, vascular plants for mechanical support and in response to pathogen attack. Peroxidases have been proposed to catalyse the dehydrogenative polymerization of monolignols into lignins, although no specific isoenzyme has been shown...... to be involved in lignin biosynthesis. Recently we isolated an extracellular anionic peroxidase, ATP A2, from rapidly lignifying Arabidopsis cell suspension culture and cloned its cDNA. Here we show that the Atp A2 promoter directs GUS reporter gene expression in lignified tissues of transgenic plants. Moreover......-coumaryl and coniferyl alcohols are preferred by ATP A2, while the oxidation of sinapyl alcohol will be sterically hindered in ATP A2 as well as in all other plant peroxidases due to an overlap with the conserved Pro-139. We suggest ATP A2 is involved in a complex regulation of the covalent cross-linking in the plant...

  13. Effects of Copper Oxide Nanoparticles on Antioxidant Enzyme Activities and on Tissue Accumulation of Oreochromis niloticus.

    Science.gov (United States)

    Tunçsoy, Mustafa; Duran, Servet; Ay, Özcan; Cicik, Bedii; Erdem, Cahit

    2017-09-01

    Accumulation of copper oxide nanoparticles (CuO NPs) in gill, liver and muscle tissues of Oreochromis niloticus and its effects on superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GPx) activities in gill and liver tissues were studied after exposing the fish to 20 µg/L Cu over 15 days. Copper levels and enzyme activities in tissues were determined using spectrophotometric (ICP-AES and UV) techniques respectively. No mortality was observed during the experiments. Copper levels increased in gill and liver tissues of O. niloticus compared to control when exposed to CuO NPs whereas exposure to metal had no effect on muscle level at the end of the exposure period. Highest accumulation of copper was observed in liver while no accumulation was detected in muscle tissue. SOD, CAT activities decreased and GPx activity increased in gill and liver tissues when exposed to CuO NPs.

  14. Glutathione S-transferases Y

    African Journals Online (AJOL)

    The effects of the non-substrate ligand rose-Bengal as well as the substrate ligands sulphobromophthalein and acrolein on the GSH peroxidase activity of these two iso-enzymes were also investigated. Depending on the ligand, the inhibition profiles of these two iso-enzymes when measured with either the peroxidase ...

  15. Pathological and biochemical changes in rat eyes exposed to gamma irradiation and benzo(A) pyrene and the protective role of glutathione and oltipraze

    International Nuclear Information System (INIS)

    Abd Elmaguid, A.; Naguib, N.I.; Saad, T.M.M.

    2007-01-01

    This study aims to evaluate the effect of exposure to carcinogenic compounds as benzo(a)pyrene in combination with other risk factor which is gamma irradiation on different eye tissues. The study was also conducted to evaluate the protective role of antioxidants such as glutathione and oltipraze before and during exposure to the risk factors. The first group of rats was kept as normal untreated control group. The second group was treated with oltipraze and glutathione for 14 days (positive control group). The third group was injected (i.p) with benzo(a)pyrene in three successive doses parallel with exposure to whole body gamma irradiation of 6 Gy divided in three successive doses ( 2 Gy/ day). The fourth group was treated with oltipraze and glutathione for 14 days then injected (i.p) with benzo(a)pyrene in the last 3 days of treatment in three successive doses parallel with exposure to the same whole body gamma irradiation as third group (6 Gy). Rat eyes were examined clinically every week. For histopathological and biochemical examinations, all groups were sacrificed at 1 month and 2 months after irradiation exposure and the eye tissues were examined by light microscope. The biochemical parameters such as lipid peroxides, SOD, GSH, GSH reductase and GSH peroxidase were estimated in blood and lens. Soluble and insoluble proteins were measured in lens only.The results showed that i.p injection of rats with benzo(a)pyrene and exposure to gamma irradiation caused alterations in eyes of rats clinically, histologically and biochemically. Animals that received glutathione and oltipraze and subjected to benzo(a)pyrene and radiation showed noticeable amelioration in the assayed parameters indicating their protective role as promising agents

  16. Hepatic glutathione and glutathione S-transferase in selenium deficiency and toxicity in the chick

    International Nuclear Information System (INIS)

    Kim, Y. S.

    1989-01-01

    First, the hepatic activity of GSH-T CDNB was increased only under conditions of severe oxidative stress produced by combined Se- and vitamin E (VE)-deficiency, indicating that VE also affects GSH metabolism. Second, the incorporation of 35 S-methionine into GSH and protein was about 4- and 2-fold higher, respectively, in Se- and VE-deficient chick hepatocytes as compared to controls. Third, chicks injected with the glutathione peroxidase (SeGSHpx) inhibitor, aurothioglucose (AuTG), showed increase hepatic GSH-T CDNB activity and plasma GSH concentration regardless of their Se status. Fourth, the effect of ascorbic acid (AA), on GSH metabolism was studied. Chicks fed 1000 ppm AA showed decreased hepatic GSH concentration compared to chicks fed no AA in a Se- and VE-deficient diet. Fifth, chicks fed excess Se showed increase hepatic activity of GSH-T CDNB and GSH concentration regardless of VE status

  17. Caribbean yellow band disease compromises the activity of catalase and glutathione S-transferase in the reef-building coral Orbicella faveolata exposed to anthracene.

    Science.gov (United States)

    Montilla, Luis Miguel; Ramos, Ruth; García, Elia; Cróquer, Aldo

    2016-05-03

    Healthy and diseased corals are threatened by different anthropogenic sources, such as pollution, a problem expected to become more severe in the near future. Despite the fact that coastal pollution and coral diseases might represent a serious threat to coral reef health, there is a paucity of controlled experiments showing whether the response of diseased and healthy corals to xenobiotics differs. In this study, we exposed healthy and Caribbean yellow band disease (CYBD)-affected Orbicella faveolata colonies to 3 sublethal concentrations of anthracene to test if enzymatic responses to this hydrocarbon were compromised in CYBD-affected tissues. For this, a 2-factorial fully orthogonal design was used in a controlled laboratory bioassay, using tissue condition (2 levels: apparently healthy and diseased) and pollutant concentration (4 levels: experimental control, 10, 30 and 100 ppb concentration) as fixed factors. A permutation-based ANOVA (PERMANOVA) was used to test the effects of condition and concentration on the specific activity of 3 enzymatic biomarkers: catalase, glutathione S-transferase, and glutathione peroxidase. We found a significant interaction between the concentration of anthracene and the colony condition for catalase (Pseudo-F = 3.84, df = 3, p < 0.05) and glutathione S-transferase (Pseudo-F = 3.29, df = 3, p < 0.05). Moreover, our results indicated that the enzymatic response to anthracene in CYBD-affected tissues was compromised, as the activity of these enzymes decreased 3- to 4-fold compared to healthy tissues. These results suggest that under a potential scenario of increasing hydrocarbon coastal pollution, colonies of O. faveolata affected with CYBD might become more vulnerable to the deleterious effects of chemical pollution.

  18. Melatonin against radiation induced free radicals: a study on tissues of Swiss albino mice

    International Nuclear Information System (INIS)

    Bhatia, A.L.; Manda, K.

    2003-01-01

    Full text: Antioxidant enzymes are part of the primary cellular defense against free radicals generated by radiation. Reports on low level chronic administration of melatonin with its antiradiation influence are scanty. Although compelling logic suggests that melatonin may be effective for a variety of disorders, the mode and optimal dose of melatonin is still not clear. Most studies have used doses of supraphysiological blood levels. Present investigation reports that melatonin in relatively lower concentrations increases the mRNA of both superoxide dismutases (SODs) and glutathione peroxidase (GSH-Px) and mediates possibly through receptors. The influence of low dose chronic administration (0.10 mg/Kg body weight/day for 15 days) of melatonin was studied against radiation-induced oxidative stress in 6 to 8 weeks old mice. Just after 24 hours of the last dose in various tissues viz. brain, liver, spleen and kidney were studied for lipid peroxidation, reduced glutathione (GSH), glutathione disulphide (GSSG), glutathione peroxidase (GSH-Px), protein, RNA, DNA and serum phosphatase activity. Radiation induced augmentation in the level of lipid peroxidation, glutathione disulphide (GSSG) and acid phosphatase was significantly ameliorated by pre-irradiation treatment with melatonin. Radiation induced depletion in the level of reduced glutathione (GSH), glutathione peroxidase (GSH-Px) and alkaline phosphatase is significantly averted by melatonin administration. Regression analysis of survival data yielded LD50/30 as 7.16 Gy and 11Gy for control (irradiation alone) and experimental (melatonin + irradiation), respectively. Animals produced a dose reduction factor (DRF) as 1.53. Radiation induced deficit in the body and organ weight was also significantly thwarted in the melatonin pre-treated mice. Results indicate the antioxidative properties of melatonin against the gamma radiation. The findings support the results showing melatonin as a free radical scavenger, and

  19. Correction of glutathione metabolism in the liver of albino rats affected by low radiation doses

    International Nuclear Information System (INIS)

    Moiseenok, A.G.; Slyshenkov, V.S.; Khomich, T.I.; Zimatkina, T.I.; Kanunnikova, N.P.

    1997-01-01

    The levels of total glutathione GSH, GSSG and the activities of glutathione reductase and glutathione peroxidase were studied in the liver of adult albino rats subjected to 3-fold external γ-irradiation throughout 2 weeks at the overall dose of 0.75 Gy after 15 h, 2 and 5 days from the last irradiation. Some animals were injected intraperitoneally with the pantothenate containing complex > 3 times on days 1-3 before the irradiation. The radiation related decrease of GSH, GSH/GSSG and the total glutathione level was prevented by the prophylactic administration of the complex and probably at the expense of the activation of the G-SH biosynthesis and/or transport in the liver by the CoA biosynthetic precursor. (author)

  20. Towards uncovering the roles of switchgrass peroxidases in plant processes

    Directory of Open Access Journals (Sweden)

    Aaron eSaathoff

    2013-06-01

    Full Text Available Herbaceous perennial plants selected as potential biofuel feedstocks had been understudied at the genomic and functional genomic levels. Recent investments, primarily by the U.S. Department of Energy, have led to the development of a number of molecular resources for bioenergy grasses, such as the partially annotated genome for switchgrass (Panicum virgatum L., and some related diploid species. In its current version, the switchgrass genome contains 65,878 gene models arising from the A and B genomes of this tetraploid grass. The availability of these gene sequences provides a framework to exploit transcriptomic data obtained from next generation sequencing platforms to address questions of biological importance. One such question pertains to discovery of genes and proteins important for biotic and abiotic stress responses, and how these components might affect biomass quality and stress response in plants engineered for a specific end purpose. It can be expected that production of switchgrass on marginal lands will expose plants to diverse stresses, including herbivory by insects. Class III plant peroxidases have been implicated in many developmental responses such as lignification and in the adaptive responses of plants to insect feeding. Here, we have analyzed the class III peroxidases encoded by the switchgrass genome, and have mined available transcriptomic datasets to develop a first understanding of the expression profiles of the class III peroxidases in different plant tissues. Lastly, we have identified switchgrass peroxidases that appear to be orthologs of enzymes shown to play key roles in lignification and plant defense responses to hemipterans.

  1. Histochemical Localization of Glutathione Dependent NBT-Reductase in Mouse Skin

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    Objective Localization of the glutathione dependent Nitroblue tetrazolium (NBT) reductase in fresh frozen sections of mouse skin and possible dependence of NBT reductase on tissue thiol levels has been investigated. Methods The fresh frozen tissue sections (8m thickness) were prepared and incubated in medium containing NBT, reduced glutathione (GSH) and phosphate buffer. The staining for GSH was performed with mercury orange. Results  The activity of the NBT-reductase in mouse skin has been found to be localized in the areas rich in glutathione and actively proliferating area of the skin. Conclusion The activity of the NBT-reductase seems to be dependent on the glutathione contents.

  2. Peroxidase gene expression during tomato fruit ripening

    International Nuclear Information System (INIS)

    Biggs, M.S.; Flurkey, W.H.; Handa, A.K.

    1987-01-01

    Auxin oxidation has been reported to play a critical role in the initiation of pear fruit ripening and a tomato fruit peroxidase (POD) has been shown to have IAA-oxidase activity. However, little is known about changes in the expression of POD mRNA in tomato fruit development. They are investigating the expression of POD mRNA during tomato fruit maturation. Fruit pericarp tissues from six stages of fruit development and ripening (immature green, mature green, breaker, turning, ripe, and red ripe fruits) were used to extract poly (A) + RNAs. These RNAs were translated in vitro in a rabbit reticulocyte lysate system using L- 35 S-methionine. The 35 S-labeled products were immunoprecipitated with POD antibodies to determine the relative proportions of POD mRNA. High levels of POD mRNA were present in immature green and mature green pericarp, but declined greatly by the turning stage of fruit ripening. In addition, the distribution of POD mRNA on free vs bound polyribosomes will be presented, as well as the presence or absence of POD mRNA in other tomato tissues

  3. Short-term exercise worsens cardiac oxidative stress and fibrosis in 8-month-old db/db mice by depleting cardiac glutathione.

    Science.gov (United States)

    Laher, Ismail; Beam, Julianne; Botta, Amy; Barendregt, Rebekah; Sulistyoningrum, Dian; Devlin, Angela; Rheault, Mark; Ghosh, Sanjoy

    2013-01-01

    Moderate exercise improves cardiac antioxidant status in young humans and animals with Type-2 diabetes (T2D). Given that both diabetes and advancing age synergistically decrease antioxidant expression in most tissues, it is unclear whether exercise can upregulate cardiac antioxidants in chronic animal models of T2D. To this end, 8-month-old T2D and normoglycemic mice were exercised for 3 weeks, and cardiac redox status was evaluated. As expected, moderate exercise increased cardiac antioxidants and attenuated oxidative damage in normoglycemic mice. In contrast, similar exercise protocol in 8-month-old db/db mice worsened cardiac oxidative damage, which was associated with a specific dysregulation of glutathione (GSH) homeostasis. Expression of enzymes for GSH biosynthesis [γ-glutamylcysteine synthase, glutathione reductase] as well as for GSH-mediated detoxification (glutathione peroxidase, glutathione-S-transferase) was lower, while toxic metabolites dependent on GSH for clearance (4-hydroxynonenal) were increased in exercised diabetic mice hearts. To validate GSH loss as an important factor for such aggravated damage, daily administration of GSH restored cardiac GSH levels in exercised diabetic mice. Such supplementation attenuated both oxidative damage and fibrotic changes in the myocardium. Expression of transforming growth factor beta (TGF-β) and its regulated genes which are responsible for such profibrotic changes were also attenuated with GSH supplementation. These novel findings in a long-term T2D animal model demonstrate that short-term exercise by itself can deplete cardiac GSH and aggravate cardiac oxidative stress. As GSH administration conferred protection in 8-month-old diabetic mice undergoing exercise, supplementation with GSH-enhancing agents may be beneficial in elderly diabetic patients undergoing exercise.

  4. GLUTATHIONE AND ANTIOXIDANT ENZYMES IN THE HEPATOPANCREAS OF CRAYFISH PROCAMBARUS CLARKII (GIRARD, 1852 OF LAKE TRASIMENO (ITALY

    Directory of Open Access Journals (Sweden)

    ELIA A. C.

    2006-01-01

    Full Text Available Antioxidant parameters, such as total glutathione, glutathione S-transferase, glutathione peroxidase, glutathione reductase, glyoxalases, catalase, and some heavy metals such as, lead, cadmium and chromium were examined in hepatopancreas of both sexes of Procambarus clarkii collected seasonally from Lake Trasimeno, from winter 2002-2003 to autumn 2003. Heavy metals content in hepatopancreas in males and females of P. clarkii was low and did not vary through the sampling periods and between sexes. On the contrary, crayfish exhibited sex-dependent differences in levels of some enzyme activities and of total glutathione, and no apparent relationship was found between contaminant burdens and antioxidant indexes in hepatopancreas. Because measured metal concentrations were low, other factors, presumably, were involved in antioxidant variations in P. clarkii and these latter seemed to be affected more by biological and environmental factors, other than those related to pollutants body burdens.

  5. CHANGES IN THE GLUTATHIONE SYSTEM IN P19 EMBRYONAL CARCINOMA CELLS UNDER HYPOXIC CONDITIONS

    Directory of Open Access Journals (Sweden)

    D. S. Orlov

    2015-01-01

    Full Text Available Introduction. According to modern perceptions, tumor growth, along with oxidative stress formation, is accompanied by hypoxia. Nowadays studying the regulation of cellular molecular system functioning by conformational changes in proteins appears to be a topical issue. Research goal was to evaluate the state of the glutathione system and the level of protein glutathionylation in P19 embryonal carcinoma (EC cells under hypoxic conditions.Material and methods. P19 EC cells (mouse embryonal carcinoma cultured under normoxic and hypox-ic conditions served the research material.The concentration of total, oxidized, reduced and protein-bound glutathione, the reduced to oxidized thiol ratio as well as glutathione peroxidase and glutathione reductase activity were determined by spectropho-tometry.Results. Glutathione imbalance was accompanied by a decrease in P19 EC cell redox status under hypox-ic conditions against the backdrop of a rise in protein-bound glutathione.Conclusions. As a result of the conducted study oxidative stress formation was identified when modeling hypoxia in P19 embryonal carcinoma cells. The rise in the concentration of protein-bound glutathione may indicate the role of protein glutathionylation in regulation of P19 cell metabolism and functions un-der hypoxia. 

  6. Glutathione and Mitochondria

    Directory of Open Access Journals (Sweden)

    Vicent eRibas

    2014-07-01

    Full Text Available Glutathione (GSH is the main nonprotein thiol in cells whose functions are dependent on the redox-active thiol of its cysteine moiety that serves as a cofactor for a number of antioxidant and detoxifying enzymes. While synthesized exclusively in the cytosol from its constituent amino acids, GSH is distributed in different compartments, including mitochondria where its concentration in the matrix equals that of the cytosol. This feature and its negative charge at physiological pH imply the existence of specific carriers to import GSH from the cytosol to the mitochondrial matrix, where it plays a key role in defense against respiration-induced reactive oxygen species and in the detoxification of lipid hydroperoxides and electrophiles. Moreover, as mitochondria play a central strategic role in the activation and mode of cell death, mitochondrial GSH has been shown to critically regulate the level of sensitization to secondary hits that induce mitochondrial membrane permeabilization and release of proteins confined in the intermembrane space that once in the cytosol engage the molecular machinery of cell death. In this review, we summarize recent data on the regulation of mitochondrial GSH and its role in cell death and prevalent human diseases, such as cancer, fatty liver disease and Alzheimer’s disease.

  7. Glutathione, Glutaredoxins, and Iron.

    Science.gov (United States)

    Berndt, Carsten; Lillig, Christopher Horst

    2017-11-20

    Glutathione (GSH) is the most abundant cellular low-molecular-weight thiol in the majority of organisms in all kingdoms of life. Therefore, functions of GSH and disturbed regulation of its concentration are associated with numerous physiological and pathological situations. Recent Advances: The function of GSH as redox buffer or antioxidant is increasingly being questioned. New functions, especially functions connected to the cellular iron homeostasis, were elucidated. Via the formation of iron complexes, GSH is an important player in all aspects of iron metabolism: sensing and regulation of iron levels, iron trafficking, and biosynthesis of iron cofactors. The variety of GSH coordinated iron complexes and their functions with a special focus on FeS-glutaredoxins are summarized in this review. Interestingly, GSH analogues that function as major low-molecular-weight thiols in organisms lacking GSH resemble the functions in iron homeostasis. Since these iron-related functions are most likely also connected to thiol redox chemistry, it is difficult to distinguish between mechanisms related to either redox or iron metabolisms. The ability of GSH to coordinate iron in different complexes with or without proteins needs further investigation. The discovery of new Fe-GSH complexes and their physiological functions will significantly advance our understanding of cellular iron homeostasis. Antioxid. Redox Signal. 27, 1235-1251.

  8. Prolonged fasting increases glutathione biosynthesis in postweaned northern elephant seals

    Science.gov (United States)

    Vázquez-Medina, José Pablo; Zenteno-Savín, Tania; Forman, Henry Jay; Crocker, Daniel E.; Ortiz, Rudy M.

    2011-01-01

    SUMMARY Northern elephant seals experience prolonged periods of absolute food and water deprivation (fasting) while breeding, molting or weaning. The postweaning fast in elephant seals is characterized by increases in the renin–angiotensin system, expression of the oxidant-producing protein Nox4, and NADPH oxidase activity; however, these increases are not correlated with increased oxidative damage or inflammation. Glutathione (GSH) is a potent reductant and a cofactor for glutathione peroxidases (GPx), glutathione-S transferases (GST) and 1-cys peroxiredoxin (PrxVI) and thus contributes to the removal of hydroperoxides, preventing oxidative damage. The effects of prolonged food deprivation on the GSH system are not well described in mammals. To test our hypothesis that GSH biosynthesis increases with fasting in postweaned elephant seals, we measured circulating and muscle GSH content at the early and late phases of the postweaning fast in elephant seals along with the activity/protein content of glutamate-cysteine ligase [GCL; catalytic (GCLc) and modulatory (GCLm) subunits], γ-glutamyl transpeptidase (GGT), glutathione disulphide reductase (GR), glucose-6-phosphate dehydrogenase (G6PDH), GST and PrxVI, as well as plasma changes in γ-glutamyl amino acids, glutamate and glutamine. GSH increased two- to four-fold with fasting along with a 40–50% increase in the content of GCLm and GCLc, a 75% increase in GGT activity, a two- to 2.5-fold increase in GR, G6PDH and GST activities and a 30% increase in PrxVI content. Plasma γ-glutamyl glutamine, γ-glutamyl isoleucine and γ-glutamyl methionine also increased with fasting whereas glutamate and glutamine decreased. Results indicate that GSH biosynthesis increases with fasting and that GSH contributes to counteracting hydroperoxide production, preventing oxidative damage in fasting seals. PMID:21430206

  9. Glutathione Preservation during Storage of Rat Lenses in Optisol-GS and Castor Oil

    DEFF Research Database (Denmark)

    Holm, Thomas; Brøgger-Jensen, Martin Rocho; Johnson, Leif

    2013-01-01

    Glutathione concentration in the lens decreases in aging and cataractous lenses, providing a marker for tissue condition. Experimental procedures requiring unfrozen lenses from donor banks rely on transportation in storage medium, affecting lens homeostasis and alterations in glutathione levels. ....... The aim of the study was to examine the effects of Optisol-GS and castor oil on lens condition, determined from their ability to maintain glutathione concentrations....

  10. Fungal peroxidases : molecular aspects and applications

    NARCIS (Netherlands)

    Conesa, A.; Punt, P.J.; Hondel, C.A.M.J.J.

    2002-01-01

    Peroxidases are oxidoreductases that utilize hydrogen peroxide to catalyze oxidative reactions. A large number of peroxidases have been identified in fungal species and are being characterized at the molecular level. In this manuscript we review the current knowledge on the molecular aspects of this

  11. Effects of mercury and selenium on glutathione metabolism and oxidative stress in mallard ducks

    Science.gov (United States)

    Hoffman, D.J.; Heinz, G.H.

    1998-01-01

    Earlier studies reported on the toxicity and related oxidative stress of different forms of Se, including seleno-D,L-methionine, in mallards (Anas platyrhynchos). This study compares the effects of Se (seleno-D,L-methionine) and Hg (methylmercury chloride) separately and in combination. Mallard drakes received one of the following diets: untreated feed (controls), or feed containing 10 ppm Se, 10 ppm Hg, or 10 ppm Se in combination with 10 ppm Hg. After 10 weeks, blood, liver, and brain samples were collected for biochemical assays. The following clinical and biochemical alterations occurred in response to mercury exposure: hematocrit and hemoglobin concentrations decreased; activities of the enzymes glutathione (GSH) peroxidase (plasma and liver), glutathione-S-transferase (liver), and glucose-6-phosphate dehydrogenase (G-6-PDH) (liver and brain) decreased; hepatic oxidized glutathione (GSSG) concentration increased relative to reduced glutathione (GSH); and lipid peroxidation in the brain was evident as detected by increased thiobarbituric reactive substances (TBARS). Effects of Se alone included increased hepatic GSSG reductase activity and brain TBARS concentration. Se in combination with Hg partially or totally alleviated effects of Hg on GSH peroxidase, G-6-PDH, and GSSG. These findings are compared in relation to field observations for diving ducks and other aquatic birds. It is concluded that since both Hg and excess Se can affect thiol status, measurement of associated enzymes in conjunction with thiol status may be a useful bioindicator to discriminate between Hg and Se effects. The ability of Se to restore the activities of G-6-PDH, GSH peroxidase, and glutathione status involved in antioxidative defense mechanisms may be crucial to biological protection from the toxic effects of methyl mercury.

  12. Wound-induced expression of horseradish peroxidase.

    Science.gov (United States)

    Kawaoka, A; Kawamoto, T; Ohta, H; Sekine, M; Takano, M; Shinmyo, A

    1994-01-01

    Peroxidases have been implicated in the responses of plants to physiological stress and to pathogens. Wound-induced peroxidase of horseradish (Armoracia rusticana) was studied. Total peroxidase activity was increased by wounding in cell wall fractions extracted from roots, stems and leaves of horseradish. On the other hand, wounding decreased the peroxidase activity in the soluble fraction from roots. The enzyme activities of the basic isozymes were induced by wounding in horseradish leaves based on data obtained by fractionation of crude enzyme in isoelectric focusing gel electrophoresis followed by activity staining. We have previously isolated genomic clones for four peroxidase genes, namely, prxC1a, prxC1b, prxC2 and prxC3. Northern blot analysis using gene-specific probes showed that mRNA of prxC2, which encodes a basic isozyme, accumulated by wounding, while the mRNAs for other peroxidase genes were not induced. Tobacco (Nicotiana tabacum) plants were transformed with four chimeric gene constructs, each consisting of a promoter from one of the peroxidase genes and the β-glucuronidase (GUS) structural gene. High level GUS activity induced in response to wounding was observed in tobacco plants containing the prxC2-GUS construct.

  13. Effect of supplementation with methionine and different fat sources on the glutathione redox system of growing chickens.

    Science.gov (United States)

    Németh, Katalin; Mézes, M; Gaál, T; Bartos, A; Balogh, K; Husvéth, F

    2004-01-01

    The effect of supplementary methionine and fats of different saturation levels on the glutathione redox system of growing broiler cockerels was studied. The diet of three groups of chicks was supplemented with corn germ oil, beef tallow and fish oil at the levels of 30 g/kg and 50 g/kg of feed, respectively. The diet of further three groups was supplemented with methionine (5 g/kg of feed) in addition to the different fat sources. Control chicks were fed with a compound feed without methionine and fat supplementation. Reduced glutathione (GSH) and glutathione disulphide (GSSG) content as well as glutathione peroxidase activity in the liver were determined and GSH/GSSG ratio was calculated at day old and then at one and three weeks of age. Our results indicate that supplementary methionine stimulates both the synthesis of the glutathione redox system and glutathione peroxidase activity in growing chickens in the first period of postnatal life, when the risk of lipid peroxidation is high due to feeding unsaturated fats in the diet.

  14. Glycosylation and thermodynamic versus kinetic stability of horseradish peroxidase

    DEFF Research Database (Denmark)

    Tams, J.W.; Welinder, Karen G.

    1998-01-01

    Glycoprotein stability, glycoprotein unfolding, horseradish peroxidase, thermodynamic stability, kinetik stability......Glycoprotein stability, glycoprotein unfolding, horseradish peroxidase, thermodynamic stability, kinetik stability...

  15. Effects of heavy metals and nitroaromatic compounds on horseradish glutathione S-transferase and peroxidase

    Czech Academy of Sciences Publication Activity Database

    Nepovím, Aleš; Podlipná, Radka; Soudek, Petr; Schröder, P.; Vaněk, Tomáš

    2004-01-01

    Roč. 57, - (2004), s. 1007-1015 ISSN 0045-6535 R&D Projects: GA ČR GP206/02/P065; GA MŠk OC 837.10 Institutional research plan: CEZ:AV0Z4055905 Keywords : GST * POX * heavy metals Subject RIV: CE - Biochemistry Impact factor: 2.359, year: 2004

  16. Glutathione peroxidase level in patients with Helicobacter pylori-associated gastritis

    Science.gov (United States)

    Tala, Z. Z.; Siregar, G. A.; Siregar, G. P.

    2018-03-01

    Helicobacter pylori (H. pylori) associated with the generation of reactive oxygen species (ROS), with leads to oxidative stress in the gastric mucosa. GPX is one of human antioxidative defense system allows the elimination of excess ROS. A cross-sectional study was in 80 consecutive gastritis patients who came to the endoscopic unit of Adam Malik General Hospital and PermataBunda Hospital in Medan, Indonesia, from May–September 2017, to determine the difference of GPX serum level between positive and negative infected H. pylori. the diagnosis of gastritis used Histopathology. Rapid urease test for diagnosis of H. pylori infection. Serum samples were obtained to determined circulating GPX. It used Univariate and bivariate analysis (Mann Whitney U test). There were 50 patients (62.5%) infected with H. pylori. GPX levels in patients with positive H. pylori gastritis were lower than those of negative H. pylori but did not differ significantly. In conclusion, there were no significant differences in GPX level between positive and negative infected H. pylori patients.

  17. Analysis of Manganese Superoxide Dismutase and Glutathione Peroxidase 1 Gene Polymorphisms in Vitiligo.

    Science.gov (United States)

    Seçkin, Havva Yıldız; Kalkan, Göknur; Bütün, İlknur; Akbaş, Ali; Baş, Yalçın; Karakuş, Nevin; Benli, İsmail

    2016-08-01

    Vitiligo is a hereditary/acquired progressive pigmentation disorder characterized by discoloration of skin as a result of melanocyte dysfunction. Recent studies have proposed that oxidant/antioxidant status plays an important role in vitiligo pathogenesis because of the toxic effects on melanocytes. In this study, we aimed to investigate possible associations of MnSOD Ala-9Val and GPx1 Pro198Leu polymorphisms with vitiligo with in Turkish population. The study group consists of 57 patients with vitiligo and 69 healthy controls. Genotyping is performed to identify MnSOD Ala-9Val and GPx1 Pro198Leu polymorphisms. The method used for genotyping was based on the PCR amplification and detection of polymorphisms by hybridization probes labeled with fluorescent dyes. Both the genotype and allele frequencies of MnSOD Ala-9Val (p = 0.817 and p = 0.553, respectively) and GPx1 Pro198Leu polymorphisms (p = 0.422 and p = 0.673, respectively) were not significantly different between vitiligo patients and the control group. Although no significant difference was found, this is the first report investigating the possible associations between the MnSOD Ala-9Val and GPx1 Pro198Leu polymorphisms in Turkish population. Further studies with large populations will be able to clarify the association better.

  18. Metabolic modulation of glutathione in whole blood components ...

    African Journals Online (AJOL)

    Lead has been found to have the ability to interfere in the metabolism and biological activities of many proteins. It has also been found that metalloelements have strong affinity for sulfhydryl (-SH) groups in biological molecules including glutathione (GSH) in tissues. Because of these facts, it was of interest to investigate ...

  19. No net splanchnic release of glutathione in man during N-acetylcysteine infusion

    DEFF Research Database (Denmark)

    Poulsen, H E; Vilstrup, H; Almdal, T

    1993-01-01

    Glutathione and amino acid concentrations were measured in arterial and hepatic vein plasma in four healthy volunteers and two patients with cirrhosis. There was no significant splanchnic efflux of glutathione (95% confidence limits, -0.501 to 0.405 mumol/min). After infusion of N...... to 0.97 +/- 0.11 (mean +/- SEM; p amino acids corresponded to an increased load on hepatic metabolic N conversion and transamination among nonessential amino acids. Splanchnic uptake of serine, alanine, cystine, isoleucine, and phenylalanine increased...... after NAC compatible with stimulated hepatic glutathione synthesis. In contrast to the rat, plasma glutathione in man probably originates mainly from extrahepatic tissues....

  20. In silico molecular modeling and docking studies on the leishmanial tryparedoxin peroxidase

    Directory of Open Access Journals (Sweden)

    Ozal Mutlu

    2014-04-01

    Full Text Available Leishmaniasis is one of the most common form of neglected parasitic disease that affects about 350 million people worldwide. Leishmanias have a trypanothione mediated hydroperoxide metabolism to eliminate endogenous or exogenous oxidative agents. Both of 2-Cys peroxiredoxin (Prx and glutathione peroxidase type tryparedoxin peroxidase (Px are the terminal enzymes in the trypanothione dependent detoxification system. Therefore absence of trypanothione redox system in mammals and the sensitivity of trypanosomatids against oxidative stress, enzymes of this pathway are drug targets candidates. In this study, 3D structure of tryparedoxin peroxidase (2-Cys peroxiredoxin type from Leishmania donovani (LdTXNPx was described by homology modeling method based on the template of tryparedoxin peroxidase from Crithidia fasciculata and selected compounds were docked to the active site pocket. The quality of the 3D structure of the model was confirmed by various web based validation programs. When compared secondary and tertiary structure of the model, it showed a typical thioredoxin fold containing a central beta-sheet and three alpha-helices. Docking study showed that the selected compound 2 (CID 16073813 interacted with the active site amino acids and binding energy was -118.675 kcal/mol.

  1. The effect of excimer laser keratectomy on corneal glutathione-related enzymes in rabbits.

    Science.gov (United States)

    Bilgihan, Ayşe; Bilgihan, Kamil; Yis, Ozgür; Yis, Nilgün Safak; Hasanreisoglu, Berati

    2003-04-01

    Glutathione related enzymes are involved in the metabolism and detoxification of cytotoxic and carcinogenic compounds as well as reactive oxygen species. Excimer laser is a very useful tool for the treatment of refractive errors and removing superficial corneal opacities. Previous studies have shown that excimer laser may initiate free radical formation in the cornea. In the present study, we evaluated the effect of excimer laser keratectomy on corneal glutathione-related enzyme activities in rabbits. Animals were divided into five groups, and all groups were compared with the controls (group 1), after epithelial scraping (group 2), transepithelial photorefractive keratectomy (PRK) (group 3), traditional PRK (group 4) and deep traditional PRK (group 5). Corneal glutathione peroxidase (GPx), glutathione S-transferase (GST) and glutathione reductase (GR) activities were measured after 24h. Corneal GPx and GR activities significantly decreased only in group 5 (p < 0.05) but GST activities significantly decreased in all groups when compared with the control group (p < 0.05). In conclusion, excimer laser inhibits the glutathione dependent defense system in the cornea, this effect becomes more prominent after high doses of excimer laser energy and antioxidants may be useful to reduce free radical mediated complications.

  2. Suppression of External NADPH Dehydrogenase—NDB1 in Arabidopsis thaliana Confers Improved Tolerance to Ammonium Toxicity via Efficient Glutathione/Redox Metabolism

    Science.gov (United States)

    Podgórska, Anna; Borysiuk, Klaudia; Tarnowska, Agata; Jakubiak, Monika; Burian, Maria; Rasmusson, Allan G.

    2018-01-01

    Environmental stresses, including ammonium (NH4+) nourishment, can damage key mitochondrial components through the production of surplus reactive oxygen species (ROS) in the mitochondrial electron transport chain. However, alternative electron pathways are significant for efficient reductant dissipation in mitochondria during ammonium nutrition. The aim of this study was to define the role of external NADPH-dehydrogenase (NDB1) during oxidative metabolism of NH4+-fed plants. Most plant species grown with NH4+ as the sole nitrogen source experience a condition known as “ammonium toxicity syndrome”. Surprisingly, transgenic Arabidopsis thaliana plants suppressing NDB1 were more resistant to NH4+ treatment. The NDB1 knock-down line was characterized by milder oxidative stress symptoms in plant tissues when supplied with NH4+. Mitochondrial ROS accumulation, in particular, was attenuated in the NDB1 knock-down plants during NH4+ treatment. Enhanced antioxidant defense, primarily concerning the glutathione pool, may prevent ROS accumulation in NH4+-grown NDB1-suppressing plants. We found that induction of glutathione peroxidase-like enzymes and peroxiredoxins in the NDB1-surpressing line contributed to lower ammonium-toxicity stress. The major conclusion of this study was that NDB1 suppression in plants confers tolerance to changes in redox homeostasis that occur in response to prolonged ammonium nutrition, causing cross tolerance among plants. PMID:29747392

  3. Tissue

    Directory of Open Access Journals (Sweden)

    David Morrissey

    2012-01-01

    Full Text Available Purpose. In vivo gene therapy directed at tissues of mesenchymal origin could potentially augment healing. We aimed to assess the duration and magnitude of transene expression in vivo in mice and ex vivo in human tissues. Methods. Using bioluminescence imaging, plasmid and adenoviral vector-based transgene expression in murine quadriceps in vivo was examined. Temporal control was assessed using a doxycycline-inducible system. An ex vivo model was developed and optimised using murine tissue, and applied in ex vivo human tissue. Results. In vivo plasmid-based transgene expression did not silence in murine muscle, unlike in liver. Although maximum luciferase expression was higher in muscle with adenoviral delivery compared with plasmid, expression reduced over time. The inducible promoter cassette successfully regulated gene expression with maximum levels a factor of 11 greater than baseline. Expression was re-induced to a similar level on a temporal basis. Luciferase expression was readily detected ex vivo in human muscle and tendon. Conclusions. Plasmid constructs resulted in long-term in vivo gene expression in skeletal muscle, in a controllable fashion utilising an inducible promoter in combination with oral agents. Successful plasmid gene transfection in human ex vivo mesenchymal tissue was demonstrated for the first time.

  4. Oxidative stress protection and glutathione metabolism in response to hydrogen peroxide and menadione in riboflavinogenic fungus Ashbya gossypii.

    Science.gov (United States)

    Kavitha, S; Chandra, T S

    2014-11-01

    Ashbya gossypii is a plant pathogen and a natural overproducer of riboflavin and is used for industrial riboflavin production. A few literature reports depict a link between riboflavin overproduction and stress in this fungus. However, the stress protection mechanisms and glutathione metabolism are not much explored in A. gossypii. In the present study, an increase in the activity of catalase and superoxide dismutase was observed in response to hydrogen peroxide and menadione. The lipid peroxide and membrane lipid peroxide levels were increased by H2O2 and menadione, indicating oxidative damage. The glutathione metabolism was altered with a significant increase in oxidized glutathione (GSSG), glutathione peroxidase (GPX), glutathione S transferase (GST), and glutathione reductase (GR) and a decrease in reduced glutathione (GSH) levels in the presence of H2O2 and menadione. Expression of the genes involved in stress mechanism was analyzed in response to the stressors by semiquantitative RT-PCR. The messenger RNA (mRNA) levels of CTT1, SOD1, GSH1, YAP1, and RIB3 were increased by H2O2 and menadione, indicating the effect of stress at the transcriptional level. A preliminary bioinformatics study for the presence of stress response elements (STRE)/Yap response elements (YRE) depicted that the glutathione metabolic genes, stress genes, and the RIB genes hosted either STRE/YRE, which may enable induction of these genes during stress.

  5. Taurine, glutathione and bioenergetics

    DEFF Research Database (Denmark)

    Hansen, Svend Høime; Grunnet, Niels

    2013-01-01

    the mitochondrial inner-membrane. The very high concentration of taurine in oxidative tissue has recently led to discussions on the role of taurine in the mitochondria, e.g. with taurine acting as a pH buffer in the mitochondrial matrix. A very important consequence of the slightly alkaline pH is the fact...... to be independent of the matrix pH. Finally a simplified model for mitochondrial oxidation is presented with introduction of GSH as redox buffer to stabilise the electrical gradient, and taurine as pH buffer stabilising the pH gradient, but simultaneously establishing the equilibrium between the NADH/NAD(+) redox...

  6. The influence of heroin abuse on glutathione-dependent enzymes in human brain.

    Science.gov (United States)

    Gutowicz, Marzena; Kaźmierczak, Beata; Barańczyk-Kuźma, Anna

    2011-01-01

    Heroin is an illicit narcotic abused by millions of people worldwide. In our earlier studies we have shown that heroin intoxication changes the antioxidant status in human brain. In the present work we continued our studies by estimating the effect of heroin abuse on reduced glutathione (GSH) and enzymes related to this cofactor, such as glutathione S-transferase detoxifying electrophilics (GST) and organic peroxides (as Se-independent glutathione peroxidase-GSHPx), and Se-dependent glutathione peroxidase (Se-GSHPx) specific mainly for hydrogen peroxide. Studies were conducted on human brains obtained from autopsy of 9 heroin abusers and 8 controls. The level of GSH and the activity of glutathione-related enzymes were determined spectrophotometrically. The expression of GST pi on mRNA and protein level was studied by RT-PCR and Western blotting, respectively. The results indicated significant increase of GST and GSHPx activities, unchanged Se-GSHPx activity, and decreased level of GSH in frontal, temporal, parietal and occipital cortex, brain stem, hippocampus, and white matter of heroin abusers. GST pi expression was increased on both mRNA and protein levels, however the increase was lower in brain stem than in other regions. Heroin affects all regions of human brain, and especially brain stem. Its intoxication leads to an increase of organic rather then inorganic peroxides in various brain regions. Glutathione S-transferase plays an important role during heroin intoxication, however its protective effect is lower in brain stem than in brain cortex or hippocampus. Copyright © 2010 Elsevier Ireland Ltd. All rights reserved.

  7. Active biomonitoring of a subtropical river using glutathione-S ...

    African Journals Online (AJOL)

    Active biomonitoring of a subtropical river using glutathione-S-transferase (GST) and heat shock proteins (HSP 70) in. Oreochromis niloticusas surrogate biomarkers of metal contamination. Victor Kurauone Muposhi1, Beaven Utete1*, Idah Sithole-Niang2 and Stanley Mukangenyama2. 1Wildlife Ecology and Conservation, ...

  8. Changes in glutathione system and lipid peroxidation in rat blood during the first hour after chlorpyrifos exposure

    Directory of Open Access Journals (Sweden)

    V. P. Rosalovsky

    2015-10-01

    Full Text Available Chlorpyrifos (CPF is a highly toxic organophosphate compound, widely used as an active substance of many insecticides. Along with the anticholinesterase action, CPF may affect other biochemical mechanisms, particularly through disrupting pro- and antioxidant balance and inducing free-radical oxidative stress. Origins and occurrence of these phenomena are still not fully understood. The aim of our work was to investigate the effects of chlorpyrifos on key parameters of glutathione system and on lipid peroxidation in rat blood in the time dynamics during one hour after exposure. We found that a single exposure to 50 mg/kg chlorpyrifos caused a linear decrease in butyryl cholinesterase activity, increased activity of glutathione peroxidase and glutathione reductase, alterations in the levels of glutathione, TBA-active products and lipid hydroperoxides during 1 hour after poisoning. The most significant changes in studied parameters were detected at the 15-30th minutes after chlorpyrifos exposure.

  9. Eosinophil peroxidase signals via epidermal growth factor-2 to induce cell proliferation.

    LENUS (Irish Health Repository)

    Walsh, Marie-Therese

    2011-11-01

    Eosinophils exert many of their inflammatory effects in allergic disorders through the degranulation and release of intracellular mediators, including a set of cationic granule proteins that include eosinophil peroxidase. Studies suggest that eosinophils are involved in remodeling. In previous studies, we showed that eosinophil granule proteins activate mitogen-activated protein kinase signaling. In this study, we investigated the receptor mediating eosinophil peroxidase-induced signaling and downstream effects. Human cholinergic neuroblastoma IMR32 and murine melanoma B16.F10 cultures, real-time polymerase chain reaction, immunoprecipitations, and Western blotting were used in the study. We showed that eosinophil peroxidase caused a sustained increase in both the expression of epidermal growth factor-2 (HER2) and its phosphorylation at tyrosine 1248, with the consequent activation of extracellular-regulated kinase 1\\/2. This, in turn, promoted a focal adhesion kinase-dependent egress of the cyclin-dependent kinase inhibitor p27(kip) from the nucleus to the cytoplasm. Eosinophil peroxidase induced a HER2-dependent up-regulation of cell proliferation, indicated by an up-regulation of the nuclear proliferation marker Ki67. This study identifies HER2 as a novel mediator of eosinophil peroxidase signaling. The results show that eosinophil peroxidase, at noncytotoxic levels, can drive cell-cycle progression and proliferation, and contribute to tissue remodeling and cell turnover in airway disease. Because eosinophils are a feature of many cancers, these findings also suggest a role for eosinophils in tumorigenesis.

  10. Glutathione treatment of hepatocellular carcinoma

    DEFF Research Database (Denmark)

    Dalhoff, K; Ranek, L; Mantoni, M

    1992-01-01

    This prospective study was undertaken to substantiate observations that glutathione (GSH) inhibits or reverses tumor growth in humans with hepatocellular carcinoma (HCC), a neoplasm with an extremely poor prognosis. Eight patients with biopsy-proven HCC not amenable to surgery were given 5 g of GSH...

  11. Glutathione Transferase from Trichoderma virens Enhances Cadmium Tolerance without Enhancing Its Accumulation in Transgenic Nicotiana tabacum

    Science.gov (United States)

    Dixit, Prachy; Mukherjee, Prasun K.; Ramachandran, V.; Eapen, Susan

    2011-01-01

    Background Cadmium (Cd) is a major heavy metal pollutant which is highly toxic to plants and animals. Vast agricultural areas worldwide are contaminated with Cd. Plants take up Cd and through the food chain it reaches humans and causes toxicity. It is ideal to develop plants tolerant to Cd, without enhanced accumulation in the edible parts for human consumption. Glutathione transferases (GST) are a family of multifunctional enzymes known to have important roles in combating oxidative stresses induced by various heavy metals including Cd. Some GSTs are also known to function as glutathione peroxidases. Overexpression/heterologous expression of GSTs is expected to result in plants tolerant to heavy metals such as Cd. Results Here, we report cloning of a glutathione transferase gene from Trichoderma virens, a biocontrol fungus and introducing it into Nicotiana tabacum plants by Agrobacterium-mediated gene transfer. Transgenic nature of the plants was confirmed by Southern blot hybridization and expression by reverse transcription PCR. Transgene (TvGST) showed single gene Mendelian inheritance. When transgenic plants expressing TvGST gene were exposed to different concentrations of Cd, they were found to be more tolerant compared to wild type plants, with transgenic plants showing lower levels of lipid peroxidation. Levels of different antioxidant enzymes such as glutathione transferase, superoxide dismutase, ascorbate peroxidase, guiacol peroxidase and catalase showed enhanced levels in transgenic plants expressing TvGST compared to control plants, when exposed to Cd. Cadmium accumulation in the plant biomass in transgenic plants were similar or lower than wild-type plants. Conclusion The results of the present study suggest that transgenic tobacco plants expressing a Trichoderma virens GST are more tolerant to Cd, without enhancing its accumulation in the plant biomass. It should be possible to extend the present results to crop plants for developing Cd tolerance and

  12. Glutathione transferase from Trichoderma virens enhances cadmium tolerance without enhancing its accumulation in transgenic Nicotiana tabacum.

    Directory of Open Access Journals (Sweden)

    Prachy Dixit

    Full Text Available BACKGROUND: Cadmium (Cd is a major heavy metal pollutant which is highly toxic to plants and animals. Vast agricultural areas worldwide are contaminated with Cd. Plants take up Cd and through the food chain it reaches humans and causes toxicity. It is ideal to develop plants tolerant to Cd, without enhanced accumulation in the edible parts for human consumption. Glutathione transferases (GST are a family of multifunctional enzymes known to have important roles in combating oxidative stresses induced by various heavy metals including Cd. Some GSTs are also known to function as glutathione peroxidases. Overexpression/heterologous expression of GSTs is expected to result in plants tolerant to heavy metals such as Cd. RESULTS: Here, we report cloning of a glutathione transferase gene from Trichoderma virens, a biocontrol fungus and introducing it into Nicotiana tabacum plants by Agrobacterium-mediated gene transfer. Transgenic nature of the plants was confirmed by Southern blot hybridization and expression by reverse transcription PCR. Transgene (TvGST showed single gene Mendelian inheritance. When transgenic plants expressing TvGST gene were exposed to different concentrations of Cd, they were found to be more tolerant compared to wild type plants, with transgenic plants showing lower levels of lipid peroxidation. Levels of different antioxidant enzymes such as glutathione transferase, superoxide dismutase, ascorbate peroxidase, guiacol peroxidase and catalase showed enhanced levels in transgenic plants expressing TvGST compared to control plants, when exposed to Cd. Cadmium accumulation in the plant biomass in transgenic plants were similar or lower than wild-type plants. CONCLUSION: The results of the present study suggest that transgenic tobacco plants expressing a Trichoderma virens GST are more tolerant to Cd, without enhancing its accumulation in the plant biomass. It should be possible to extend the present results to crop plants for

  13. Glutathione and its dependent enzymes' modulatory responses to toxic metals and metalloids in fish--a review.

    Science.gov (United States)

    Srikanth, K; Pereira, E; Duarte, A C; Ahmad, I

    2013-04-01

    Toxic metals and metalloid are being rapidly added from multiple pathways to aquatic ecosystem and causing severe threats to inhabiting fauna including fish. Being common in all the type of aquatic ecosystems such as freshwater, marine and brackish water fish are the first to get prone to toxic metals and metalloids. In addition to a number of physiological/biochemical alterations, toxic metals and metalloids cause enhanced generation of varied reactive oxygen species (ROS) ultimately leading to a situation called oxidative stress. However, as an important component of antioxidant defence system in fish, the tripeptide glutathione (GSH) directly or indirectly regulates the scavenging of ROS and their reaction products. Additionally, several other GSH-associated enzymes such as GSH reductase (GR, EC 1.6.4.2), GSH peroxidase (EC 1.11.1.9), and GSH sulfotransferase (glutathione-S-transferase (GST), EC 2.5.1.18) cumulatively protect fish against ROS and their reaction products accrued anomalies under toxic metals and metalloids stress conditions. The current review highlights recent research findings on the modulation of GSH, its redox couple (reduced glutathione/oxidised glutathione), and other GSH-related enzymes (GR, glutathione peroxidase, GST) involved in the detoxification of harmful ROS and their reaction products in toxic metals and metalloids-exposed fish.

  14. [Effects of melaxen and valdoxan on the activity of glutathione antioxidant system and NADPH-producing enzymes in rat heart under experimental hyperthyroidism conditions].

    Science.gov (United States)

    Gorbenko, M V; Popova, T N; Shul'gin, K K; Popov, S S

    2013-01-01

    The effects of melaxen and valdoxan on the activity of glutathione antioxidant system and some NADPH-producing enzymes have been studied under conditions of experimental hyperthyroidism in rat heart. Under the action of these drugs, reduced glutathione (GSH) content increased as compared to values observed under the conditions of pathology. It has been established that the activities of glutathione reductase (GR), glutathione peroxidase (GP), glucose-6-phosphate dehydrogenase, and NADP isocitrate dehydrogenase (increased under pathological conditions) change toward the intact control values upon the introduction of both drugs. The influence of melaxen and valdoxan, capable of producing antioxidant effect, leads apparently to the inhibition of free-radical oxidation processes and, as a consequence, the reduction of mobilization degree of the glutathione antioxidant system.

  15. Direct Electrochemistry of Horseradish Peroxidase-Gold Nanoparticles Conjugate

    Directory of Open Access Journals (Sweden)

    Chanchal K. Mitra

    2009-02-01

    Full Text Available We have studied the direct electrochemistry of horseradish peroxidase (HRP coupled to gold nanoparticles (AuNP using electrochemical techniques, which provide some insight in the application of biosensors as tools for diagnostics because HRP is widely used in clinical diagnostics kits. AuNP capped with (i glutathione and (ii lipoic acid was covalently linked to HRP. The immobilized HRP/AuNP conjugate showed characteristic redox peaks at a gold electrode. It displayed good electrocatalytic response to the reduction of H2O2, with good sensitivity and without any electron mediator. The covalent linking of HRP and AuNP did not affect the activity of the enzyme significantly. The response of the electrode towards the different concentrations of H2O2 showed the characteristics of Michaelis Menten enzyme kinetics with an optimum pH between 7.0 to 8.0. The preparation of the sensor involves single layer of enzyme, which can be carried out efficiently and is also highly reproducible when compared to other systems involving the layer-by-layer assembly, adsorption or encapsulation of the enzyme. The immobilized AuNP-HRP can be used for immunosensor applications

  16. Barley peroxidase isozymes. Expression and post-translational modification in mature seeds as identified by two-dimensional gel electrophoresis and mass spectrometry

    DEFF Research Database (Denmark)

    Laugesen, Sabrina; Bak-Jensen, Kristian Sass; Hägglund, Per

    2007-01-01

    spectrometric analysis. Distinct peroxidase spot patterns divided the 16 cultivars tested into two groups. The distribution of the three isozymes in different seed tissues (endosperm, embryo, and aleurone layer) suggested the peroxidases to play individual albeit partially overlapping roles during germination...

  17. Oxidant-antioxidant status in tissue samples of oral leukoplakia

    Directory of Open Access Journals (Sweden)

    Kumar Chandan Srivastava

    2014-01-01

    Full Text Available Background: Imbalances between the oxidant-antioxidant status have been implicated in the pathogenesis of several diseases, including oral cancer. Majority of oral cancer are preceded by a well-recognized group of pre-malignant lesions. However, only a small fraction of those lesions, undergo malignant transformation. Hence, there is a great need to identify biological markers, which will assist in identifying lesion carrying high-risk. This study aims to evaluate and compare the status of oxidative stress and antioxidant enzymes in tissue samples of patients with various clinicopathological stages of oral pre-malignancy. Materials and Methods: A case control study consisting of 20 new histopathologically proven leukoplakia patients and equal number of age, sex, and habit matched healthy subjects were recruited for this study. Their tissue samples were subjected to evaluation of lipid peroxidation product, thiobarbituric acid reactive substances and antioxidant enzymes, namely, superoxide dismutase (SOD, catalase (CAT, reduced glutathione (GSH, and glutathione peroxidase (GPx using spectrophotometric methods. The data are expressed as mean ± standard deviation. The statistical comparisons were performed by independent Student′s unpaired t-test and one-way analysis of variance. Pearson′s correlation was performed for the biochemical parameters within the group and between the groups. For statistically significant correlations, simple linear regression was performed. P- value < 0.05 was considered statistically significant. Results: Significant reduction in lipid peroxidation (P < 0.001 SOD and CAT (P < 0.001 was observed in the tissue of leukoplakia patients as compared to the healthy controls. On the other hand, GSH and GPx were significantly increased in tumor samples. Conclusion: Reduced lipid peroxidation and increased activity of GSH and GPx provides the suitable environment for the tumor growth and malignant transformation in the later

  18. 1-Methyl-4-phenylpyridinium-induced alterations of glutathione status in immortalized rat dopaminergic neurons

    International Nuclear Information System (INIS)

    Drechsel, Derek A.; Liang, L.-P.; Patel, Manisha

    2007-01-01

    Decreased glutathione levels associated with increased oxidative stress are a hallmark of numerous neurodegenerative diseases, including Parkinson's disease. GSH is an important molecule that serves as an anti-oxidant and is also a major determinant of cellular redox environment. Previous studies have demonstrated that neurotoxins can cause changes in reduced and oxidized GSH levels; however, information regarding steady state levels remains unexplored. The goal of this study was to characterize changes in cellular GSH levels and its regulatory enzymes in a dopaminergic cell line (N27) following treatment with the Parkinsonian toxin, 1-methyl-4-phenylpyridinium (MPP + ). Cellular GSH levels were initially significantly decreased 12 h after treatment, but subsequently recovered to values greater than controls by 24 h. However, oxidized glutathione (GSSG) levels were increased 24 h following treatment, concomitant with a decrease in GSH/GSSG ratio prior to cell death. In accordance with these changes, ROS levels were also increased, confirming the presence of oxidative stress. Decreased enzymatic activities of glutathione reductase and glutamate-cysteine ligase by 20-25% were observed at early time points and partly account for changes in GSH levels after MPP + exposure. Additionally, glutathione peroxidase activity was increased 24 h following treatment. MPP + treatment was not associated with increased efflux of glutathione to the medium. These data further elucidate the mechanisms underlying GSH depletion in response to the Parkinsonian toxin, MPP +

  19. Antisense Suppression of 2-Cysteine Peroxiredoxin in Arabidopsis Specifically Enhances the Activities and Expression of Enzymes Associated with Ascorbate Metabolism But Not Glutathione Metabolism1

    Science.gov (United States)

    Baier, Margarete; Noctor, Graham; Foyer, Christine H.; Dietz, Karl-Josef

    2000-01-01

    The aim of this study was to characterize the effect of decreased 2-cysteine peroxiredoxin (2-CP) on the leaf anti-oxidative system in Arabidopsis. At three stages of leaf development, two lines of transgenic Arabidopsis mutants with decreased contents of chloroplast 2-CP were compared with wild type and a control line transformed with an empty vector. Glutathione contents and redox state were similar in all plants, and no changes in transcript levels for enzymes involved in glutathione metabolism were observed. Transcript levels for chloroplastic glutathione peroxidase were much lower than those for 2-CP, and both cytosolic and chloroplastic glutathione peroxidase were not increased in the mutants. In contrast, the foliar ascorbate pool was more oxidized in the mutants, although the difference decreased with plant age. The activities of thylakoid and stromal ascorbate peroxidase and particularly monodehydroascorbate reductase were increased as were transcripts for these enzymes. No change in dehydroascorbate reductase activity was observed, and effects on transcript abundance for glutathione reductase, catalase, and superoxide dismutase were slight or absent. The results demonstrate that 2-CP forms an integral part of the anti-oxidant network of chloroplasts and is functionally interconnected with other defense systems. Suppression of 2-CP leads to increased expression of other anti-oxidative genes possibly mediated by increased oxidation state of the leaf ascorbate pool. PMID:11027730

  20. Glutathione transferase-mediated benzimidazole-resistance in Fusarium graminearum.

    Science.gov (United States)

    Sevastos, A; Labrou, N E; Flouri, F; Malandrakis, A

    2017-09-01

    Fusarium graminearum laboratory mutants moderately (MR) and highly (HR) benzimidazole-resistant, carrying or not target-site mutations at the β 2 -tubulin gene were utilized in an attempt to elucidate the biochemical mechanism(s) underlying the unique BZM-resistance paradigm of this fungal plant pathogen. Relative expression analysis in the presence or absence of carbendazim (methyl-2-benzimidazole carbamate) using a quantitative Real Time qPCR (RT-qPCR) revealed differences between resistant and the wild-type parental strain although no differences in expression levels of either β 1 - or β 2 -tubulin homologue genes were able to fully account for two of the highly resistant phenotypes. Glutathione transferase (GST)-mediated detoxification was shown to be -at least partly- responsible for the elevated resistance levels of a HR isolate bearing the β 2 -tubulin Phe200Tyr resistance mutation compared with another MR isolate carrying the same mutation. This benzimidazole-resistance mechanism is reported for the first time in F. graminearum. No indications of detoxification involved in benzimidazole resistance were found for the rest of the isolates as revealed by GST and glutathione peroxidase (GPx) activities and bioassays using monoxygenase and hydrolase detoxification enzyme inhibiting synergists. Interestingly, besides the Phe200Tyr mutation-carrying HR isolate, the remaining highly-carbendazim resistant phenotypes could not be associated with any of the target site modification/overproduction, detoxification or reduced uptake-increased efflux mechanisms. Copyright © 2016 Elsevier B.V. All rights reserved.

  1. Effects of Ionizing Radiation and Glutathione Precursor on Antioxidant Enzyme and Cell Survival in Yeast

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Jinkyu; Roh, Changhyun; Ryu, Taeho; Park, Jiyoung [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of); Nili, Michael A. [Oxiage Cosmeceutical Research Institute, Virginia (United States)

    2013-05-15

    Cells react to such an induced oxidative stress through scavenging the generated reactive oxygen species to reduce oxidative damage. Antioxidant enzymes such as glutathione peroxidase, catalase, and superoxide dismutase are immediately triggered for reactive oxygen species. N-acetyl-L-cysteine (NAC), a precursor of glutathione, is one of the antioxidants. The effect of NAC as an antioxidant and/or a cell rescue agent was investigated in the present study. Glutathione (GSH) is the most abundant intracellular thiol, which involves in antioxidant defense via direct interaction with ROS or via activities of detoxication enzymes like glutathione peroxidases (GPx). NAC flowed in the cell is converted to cysteine by deacetylation, that is supplied to the depleted GSH by oxidative stress. NAC prevents the depletion of GSH by radiation, increases the production of GSH, and improves enzymes activity such as GPx and alkaline phosphatase. Cell growth and survivorship and transcriptional level of glutathione gene are analyzed in two yeast strains exposed to combined treatment of NAC with gamma-rays. The effect of NAC on cell growth was measured during 72 hours. The cell growth was hampered by higher concentrations of NAC at stationary phase. NAC, however, didn't affect the cell division at the exponential phase. The survival of the cells decreased with radiation dose. The cell viability of the strain W303-1A was reduced significantly at the low dose (10 and 30 Gy). By comparison, the strain W303-1A was more sensitive to radiation with having a half lethal dose (LD{sub 50}) of about 20 Gy. The quantitative RT-PCR analysis showed that the transcriptional expression of antioxidant enzyme gene GPX1 increased after irradiation while the expression of the gene decreased by the combined treatment of NAC with 100 Gy radiation. The present study shows that NAC can directly scavenge ROS against oxidative stress in vivo. In conclusion, NAC can prevent radiation-induced oxidative

  2. Effects of Ionizing Radiation and Glutathione Precursor on Antioxidant Enzyme and Cell Survival in Yeast

    International Nuclear Information System (INIS)

    Kim, Jinkyu; Roh, Changhyun; Ryu, Taeho; Park, Jiyoung; Nili, Michael A.

    2013-01-01

    Cells react to such an induced oxidative stress through scavenging the generated reactive oxygen species to reduce oxidative damage. Antioxidant enzymes such as glutathione peroxidase, catalase, and superoxide dismutase are immediately triggered for reactive oxygen species. N-acetyl-L-cysteine (NAC), a precursor of glutathione, is one of the antioxidants. The effect of NAC as an antioxidant and/or a cell rescue agent was investigated in the present study. Glutathione (GSH) is the most abundant intracellular thiol, which involves in antioxidant defense via direct interaction with ROS or via activities of detoxication enzymes like glutathione peroxidases (GPx). NAC flowed in the cell is converted to cysteine by deacetylation, that is supplied to the depleted GSH by oxidative stress. NAC prevents the depletion of GSH by radiation, increases the production of GSH, and improves enzymes activity such as GPx and alkaline phosphatase. Cell growth and survivorship and transcriptional level of glutathione gene are analyzed in two yeast strains exposed to combined treatment of NAC with gamma-rays. The effect of NAC on cell growth was measured during 72 hours. The cell growth was hampered by higher concentrations of NAC at stationary phase. NAC, however, didn't affect the cell division at the exponential phase. The survival of the cells decreased with radiation dose. The cell viability of the strain W303-1A was reduced significantly at the low dose (10 and 30 Gy). By comparison, the strain W303-1A was more sensitive to radiation with having a half lethal dose (LD 50 ) of about 20 Gy. The quantitative RT-PCR analysis showed that the transcriptional expression of antioxidant enzyme gene GPX1 increased after irradiation while the expression of the gene decreased by the combined treatment of NAC with 100 Gy radiation. The present study shows that NAC can directly scavenge ROS against oxidative stress in vivo. In conclusion, NAC can prevent radiation-induced oxidative stress by

  3. [Alternative nutrition and glutathione levels].

    Science.gov (United States)

    Krajcovicová-Kudlácková, M; Simoncic, R; Béderová, A; Brtková, A; Magálová, T; Barteková, S

    1999-08-30

    Low protein quality and quantity is reported to be a possible risk of alternative nutrition. Pulses contain 18-41% of methionine in relation to reference protein, moreover, its content in cereals is by one half lower. Therefore vegetarians and vegans may have an insufficient intake of sulphur-containing amino acids that may subsequently affect glutathione values (precursors of its synthesis). In groups of adults on an alternative diet--lactoovovegetarians (n = 47) and vegans (n = 44) aged 19-62 years with average duration on a vegetarian or vegan diet of 7.6 and 4.9 years, respectively, glutathione levels (GSH) were measured in erythrocytes (spectrophotometrically), as well as the activity of GSH-dependent enzymes. As nutritional control (n = 42) served an average sample of omnivores selected from a group of 489 examined, apparently healthy subjects of the same age range living in the same region. One to low protein intake (56% of RDA) exclusively of plant origin significantly lower levels of total proteins were observed in vegans with a 16% frequency of hypoproteinaemia (vs 0% in omnivores). In comparison to omnivores a significantly lower glutathione level was found (4.28 +/- 0.12 vs 4.84 +/- 0.14 mumol/g Hb, P vegan diet also in adult age.

  4. Garlic protects the glutathione redox cycle in irradiated rats

    International Nuclear Information System (INIS)

    Abu-Ghadeer, A.R.M.; Osman, S.A.A.; Abbady, M.M.

    1999-01-01

    The aim of the present study is to evaluate the possible radioprotective role of garlic oil on the glutathione redox cycle (GSH, GSH-Px, GR and G6-PD) in blood and tissues (liver, spleen and intestine) of irradiated rats. Garlic oil was orally administered to rats (100 mg/Kg- b.w.) for 7 days before exposure to a fractionated of whole body gamma irradiation up to 9 Gy (3 Gy X 3 at 2 days intervals) and during the whole period of irradiation. The data showed that radiation exposure caused significant inhibition of the biochemical parameters in blood and tissue of irradiated rats all over the investigation periods (3,7 and 15 days). Garlic oil ameliorated the decrease in the tested parameters with noticeable effect on the 15 Th. day after radiation exposure. It is concluded that garlic oil could control the radiation induced changes in the glutathione redox cycle and provided some radioprotective effect

  5. Guaiacol Peroxidase Zymography for the Undergraduate Laboratory

    Science.gov (United States)

    Wilkesman, Jeff; Castro, Diana; Contreras, Lellys M.; Kurz, Liliana

    2014-01-01

    This laboratory exercise presents a novel way to introduce undergraduate students to the specific detection of enzymatic activity by electrophoresis. First, students prepare a crude peroxidase extract and then analyze the homogenate via electrophoresis. Zymography, that is, a SDS-PAGE method to detect enzyme activity, is used to specifically…

  6. Heterologous Expression of Peroxidases : Chapter 12

    NARCIS (Netherlands)

    Christien Lokman; S. de Weert

    2010-01-01

    This monograph describes many applications of peroxidase-based biocatalysis in the biotechnology industry. The need for such a book emerges from the considerable amount of new data regarding the phylogeny, reaction mechanisms, thermodynamic characterization and structural features of fungal and

  7. "Chitin-specific" peroxidases in plants.

    Science.gov (United States)

    Maksimov, I V; Cherepanova, E A; Khairullin, R M

    2003-01-01

    The activity of various plant peroxidases and the ability of their individual isoforms to bind chitin was studied. Some increase in peroxidase activity was observed in crude extracts in the presence of chitin. Activated peroxidases of some species fell in the fraction not sorbed on chitin and those of other species can bind chitin. Only anionic isoperoxidases from oat (Avena sativa), rice (Oryza sativa), horseradish (Armoracia rusticana), garden radish (Raphanus sativus var. radicula), peanut (Arachis hypogaea), and tobacco (Nicotiana tabacum Link et Otto) were sorbed on chitin. Both anionic and cationic isoforms from pea (Pisum sativum), galega(Galega orientalis), cucumber (Cucumis sativus), and zucchini (Cucurbita pepo L.) were sorbed on chitin. Peroxidase activation under the influence of chitin was correlated to the processes that occur during hypersensitive reaction and lignification of sites, in which pathogenic fungus penetrates into a plant. The role of chitin-specific isoperoxidases in inhibition of fungal growth and connection of this phenomenon with structural characteristics of isoperoxidases are also discussed.

  8. Peroxidase-like activity of magnetoferritin

    Czech Academy of Sciences Publication Activity Database

    Melníková, V.; Pospíšková, K.; Mitróová, Z.; Kopčanský, P.; Šafařík, Ivo

    2014-01-01

    Roč. 181, 3-4 (2014), s. 295-301 ISSN 0026-3672 R&D Projects: GA MŠk(CZ) LD13021 Institutional support: RVO:67179843 Keywords : magnetoferritin * magnetic nanoparticles * peroxidase-like activity * hydrogen peroxide * oxidative stress Subject RIV: CE - Biochemistry Impact factor: 3.741, year: 2014

  9. Occurrence and properties of Petunia peroxidase a

    NARCIS (Netherlands)

    Hendriks, T.

    1989-01-01

    Peroxidases are probably the most extensively studied enzymes in higher plants. Various isoenzymes occur as soluble proteins in the apoplast and in the vacuole, or are bound to membranes and cell walls. Their occurrence is often organ-specific and developmentally controlled, and there is

  10. Thyroid peroxidase autoantibodies in euthyroid subjects

    NARCIS (Netherlands)

    Prummel, Mark F.; Wiersinga, Wilmar M.

    2005-01-01

    Thyroid peroxidase (TPO) is a key enzyme in the formation of thyroid hormones and a major autoantigen in autoimmune thyroid diseases. Titers of TPO antibodies also correlate with the degree of lymphocytic infiltration in euthyroid subjects, and they are frequently present in euthyroid subjects

  11. Peroxidase gene discovery from the horseradish transcriptome.

    Science.gov (United States)

    Näätsaari, Laura; Krainer, Florian W; Schubert, Michael; Glieder, Anton; Thallinger, Gerhard G

    2014-03-24

    Horseradish peroxidases (HRPs) from Armoracia rusticana have long been utilized as reporters in various diagnostic assays and histochemical stainings. Regardless of their increasing importance in the field of life sciences and suggested uses in medical applications, chemical synthesis and other industrial applications, the HRP isoenzymes, their substrate specificities and enzymatic properties are poorly characterized. Due to lacking sequence information of natural isoenzymes and the low levels of HRP expression in heterologous hosts, commercially available HRP is still extracted as a mixture of isoenzymes from the roots of A. rusticana. In this study, a normalized, size-selected A. rusticana transcriptome library was sequenced using 454 Titanium technology. The resulting reads were assembled into 14871 isotigs with an average length of 1133 bp. Sequence databases, ORF finding and ORF characterization were utilized to identify peroxidase genes from the 14871 isotigs generated by de novo assembly. The sequences were manually reviewed and verified with Sanger sequencing of PCR amplified genomic fragments, resulting in the discovery of 28 secretory peroxidases, 23 of them previously unknown. A total of 22 isoenzymes including allelic variants were successfully expressed in Pichia pastoris and showed peroxidase activity with at least one of the substrates tested, thus enabling their development into commercial pure isoenzymes. This study demonstrates that transcriptome sequencing combined with sequence motif search is a powerful concept for the discovery and quick supply of new enzymes and isoenzymes from any plant or other eukaryotic organisms. Identification and manual verification of the sequences of 28 HRP isoenzymes do not only contribute a set of peroxidases for industrial, biological and biomedical applications, but also provide valuable information on the reliability of the approach in identifying and characterizing a large group of isoenzymes.

  12. Tissue-specific bioaccumulation and oxidative stress responses in juvenile Japanese flounder ( Paralichthys olivaceus) exposed to mercury

    Science.gov (United States)

    Huang, Wei; Cao, Liang; Ye, Zhenjiang; Lin, Longshan; Chen, Quanzhen; Dou, Shuozeng

    2012-07-01

    To understand mercury (Hg) toxicity in marine fish, we measured Hg accumulation in juvenile Japanese flounder ( Paralichthys olivaceus) and assessed the effects on growth and antioxidant responses. After Hg exposure (control, 5, 40, and 160 μg/L Hg) for 28 d, fish growth was significantly reduced. The accumulation of Hg in fish was dose-dependent and tissue-specific, with the maximum accumulation in kidney and liver, followed by gills, bone, and muscle. Different antioxidants responded differently to Hg exposure to cope with the induction of lipid peroxidation (LPO), which was also tissue-specific and dosedependent. As Hg concentration increased, superoxide dismutase (SOD) and catalase (CAT) activities increased significantly, whereas glutathione S -transferase (GST) activity and glutathione (GSH) levels decreased significantly in the gills. SOD and glutathione peroxidase (GPx) activities and the GSH level increased significantly in the liver. SOD activity and GSH levels increased significantly, but CAT activity decreased significantly with an increase in Hg concentration in the kidney. LPO was induced significantly by elevated Hg in the gills and kidney but was least affected in the liver. Therefore, oxidative stress biomarkers in gills were more sensitive than those in the liver and kidney to Hg exposure. Thus, the gills have potential as bioindicators for evaluating Hg toxicity in juvenile flounder.

  13. Self-Assembled Complexes of Horseradish Peroxidase with Magnetic Nanoparticles Showing Enhanced Peroxidase Activity

    KAUST Repository

    Corgié , Sté phane C.; Kahawong, Patarawan; Duan, Xiaonan; Bowser, Daniel; Edward, Joseph B.; Walker, Larry P.; Giannelis, Emmanuel P.

    2012-01-01

    Bio-nanocatalysts (BNCs) consisting of horseradish peroxidase (HRP) self-assembled with magnetic nanoparticles (MNPs) enhance enzymatic activity due to the faster turnover and lower inhibition of the enzyme. The size and magnetization of the MNPs

  14. Induction of 33-kD and 60-kD peroxidases during ethylene-induced senescence of cucumber cotyledons

    International Nuclear Information System (INIS)

    Abeles, F.B.; Dunn, L.J.; Morgens, P.; Callahan, A.; Dinterman, R.E.; Schmidt, J.

    1988-01-01

    Ethylene enhanced the senescence of cucumber (Cucumis sativus L. cv Poinsett 76) cotyledons. The effect of 10 microliters per liter ethylene was inhibited by 1 millimolar silver thiosulfate, an inhibitor of ethylene action. An increase in proteins with molecular weights of 33 to 30 kilodaltons and lower molecular weights (25, 23, 20, 16, 12 and 10 kilodaltons) were observed in sodium dodecyl sulfate-polyacrylamide gel electrophoresis gels after ethylene enhanced senescence. The measurement of DNase and RNase activity in gels indicated that these new proteins were not nucleases. Two proteins from ethylene-treated cotyledons were purified on the basis of their association with a red chromaphore and subsequently were identified as peroxidases. The molecular weights and isoelectric points (pI) of two of these peroxidases were 33 kilodaltons (cationic, pI = 8.9) and 60 kilodaltons (anionic, pI = 4.0). The observation that [ 35 S]Na 2 SO 4 was incorporated into these proteins during ethylene-enhanced senescence suggests that these peroxidases represent newly synthesized proteins. Antibodies to the 33-kilodalton peroxidase precipitated two in vitro translation products from RNA isolated from ethylene-treated but not from control cucumber seedlings. This indicates that the increase in 33-kilodalton peroxidase activity represents de novo protein synthesis. Both forms of peroxidase degraded chlorophyll in vitro, which is consistent with the hypothesis that peroxidases have catabolic or scavenging functions in senescent tissues

  15. Characteristics of estrogen-induced peroxidase in mouse uterine luminal fluid

    International Nuclear Information System (INIS)

    Jellinck, P.H.; Newbold, R.R.; McLachlan, J.A.

    1991-01-01

    Peroxidase activity in the uterine luminal fluid of mice treated with diethylstilbestrol was measured by the guaiacol assay and also by the formation of 3H2O from [2-3H]estradiol. In the radiometric assay, the generation of 3H2O and 3H-labeled water-soluble products was dependent on H2O2 (25 to 100 microM), with higher concentrations being inhibitory. Tyrosine or 2,4-dichlorophenol strongly enhanced the reaction catalyzed either by the luminal fluid peroxidase or the enzyme in the CaCl2 extract of the uterus, but decreased the formation of 3H2O from [2-3H]estradiol by lactoperoxidase in the presence of H2O2 (80 microM). NADPH, ascorbate, and cytochrome c inhibited both luminal fluid and uterine tissue peroxidase activity to the same extent, while superoxide dismutase showed a marginal activating effect. Lactoferrin, a major protein component of uterine luminal fluid, was shown not to contribute to its peroxidative activity, and such an effect by prostaglandin synthase was also ruled out. However, it was not possible to exclude eosinophil peroxidase, brought to the uterus after estrogen stimulation, as being the source of peroxidase activity in uterine luminal fluid

  16. The study of ascorbate peroxidase, catalase and peroxidase during in vitro regeneration of Argyrolobium roseum.

    Science.gov (United States)

    Habib, Darima; Chaudhary, Muhammad Fayyaz; Zia, Muhammad

    2014-01-01

    Here, we demonstrate the micropropagation protocol of Argyrolobium roseum (Camb.), an endangered herb exhibiting anti-diabetic and immune-suppressant properties, and antioxidant enzymes pattern is evaluated. Maximum callogenic response (60 %) was observed from leaf explant at 1.0 mg L(-1) 1-nephthalene acetic acid (NAA) and 0.5 mg L(-1) 6-benzyl aminopurine (BA) in Murashige and Skoog (MS) medium using hypocotyl and root explants (48 % each). Addition of AgNO3 and PVP in the culture medium led to an increase in callogenic response up to 86 % from leaf explant and 72 % from hypocotyl and root explants. The best shooting response was observed in the presence of NAA, while maximum shoot length and number of shoots were achieved based on BA-supplemented MS medium. The regenerated shoots were rooted and successfully acclimatized under greenhouse conditions. Catalase and peroxidase enzymes showed ascending pattern during in vitro plant development from seed while ascorbate peroxidase showed descending pattern. Totally reverse response of these enzymes was observed during callus induction from three different explants. During shoot induction, catalase and peroxidase increased at high rate while there was a mild reduction in ascorbate peroxidase activity. Catalase and peroxidase continuously increased; on the other hand, ascorbate peroxidase activity decreased during root development and acclimatization states. The protocol described here can be employed for the mass propagation and genetic transformation of this rare herb. This study also highlights the importance and role of ascorbate peroxidase, catalase, and peroxidase in the establishment of A. roseum in vitro culture through callogenesis and organogenesis.

  17. Peroxidase isozyme profiles in some sweet cherry rootstocks and ...

    African Journals Online (AJOL)

    PERS

    2012-01-10

    , 2005). Santamour (1980) defined role of peroxidase in graft compatibility as; 1) lignification is essential for a strong and permanent graft union; 2) peroxidase isoenzymes mediate the polymeri- zation of cinnamic alcohols to ...

  18. Glutathione in plants: an integrated overview.

    Science.gov (United States)

    Noctor, Graham; Mhamdi, Amna; Chaouch, Sejir; Han, Yi; Neukermans, Jenny; Marquez-Garcia, Belen; Queval, Guillaume; Foyer, Christine H

    2012-02-01

    Plants cannot survive without glutathione (γ-glutamylcysteinylglycine) or γ-glutamylcysteine-containing homologues. The reasons why this small molecule is indispensable are not fully understood, but it can be inferred that glutathione has functions in plant development that cannot be performed by other thiols or antioxidants. The known functions of glutathione include roles in biosynthetic pathways, detoxification, antioxidant biochemistry and redox homeostasis. Glutathione can interact in multiple ways with proteins through thiol-disulphide exchange and related processes. Its strategic position between oxidants such as reactive oxygen species and cellular reductants makes the glutathione system perfectly configured for signalling functions. Recent years have witnessed considerable progress in understanding glutathione synthesis, degradation and transport, particularly in relation to cellular redox homeostasis and related signalling under optimal and stress conditions. Here we outline the key recent advances and discuss how alterations in glutathione status, such as those observed during stress, may participate in signal transduction cascades. The discussion highlights some of the issues surrounding the regulation of glutathione contents, the control of glutathione redox potential, and how the functions of glutathione and other thiols are integrated to fine-tune photorespiratory and respiratory metabolism and to modulate phytohormone signalling pathways through appropriate modification of sensitive protein cysteine residues. © 2011 Blackwell Publishing Ltd.

  19. Biochemical response of hybrid black poplar tissue culture (Populus × canadensis) on water stress.

    Science.gov (United States)

    Popović, B M; Štajner, D; Ždero-Pavlović, R; Tari, I; Csiszár, J; Gallé, Á; Poór, P; Galović, V; Trudić, B; Orlović, S

    2017-05-01

    In this study, poplar tissue culture (hybrid black poplar, M1 genotype) was subjected to water stress influenced by polyethyleneglycol 6000 (100 and 200 mOsm PEG 6000). The aim of the research was to investigate the biochemical response of poplar tissue culture on water deficit regime. Antioxidant status was analyzed including antioxidant enzymes, superoxide-dismutase (SOD), catalase (CAT), guiacol-peroxidase (GPx), glutathione-peroxidase (GSH-Px), glutathione-reductase, reduced glutathione, total phenol content, Ferric reducing antioxidant power and DPPH radical antioxidant power. Polyphenol oxidase and phenylalanine-ammonium-lyase were determined as enzymatic markers of polyphenol metabolism. Among oxidative stress parameters lipid peroxidation, carbonyl-proteins, hydrogen-peroxide, reactive oxygen species, nitric-oxide and peroxynitrite were determined. Proline, proline-dehydrogenase and glycinebetaine were measured also as parameters of water stress. Cell viability is finally determined as a biological indicator of osmotic stress. It was found that water stress induced reactive oxygen and nitrogen species and lipid peroxidation in leaves of hybrid black poplar and reduced cell viability. Antioxidant enzymes including SOD, GPx, CAT and GSH-Px were induced but total phenol content and antioxidant capacity were reduced by PEG 6000 mediated osmotic stress. The highest biochemical response and adaptive reaction was the increase of proline and GB especially by 200 mOsm PEG. While long term molecular analysis will be necessary to fully address the poplar potentials for water stress adaptation, our results on hybrid black poplar suggest that glycine-betaine, proline and PDH enzyme might be the most important markers of poplar on water stress and that future efforts should be focused on these markers and strategies to enhance their concentration in poplar.

  20. Luffa aegyptiaca (Gourd) Fruit Juice as a Source of Peroxidase

    OpenAIRE

    Yadav, R. S. S.; Yadav, K. S.; Yadav, H. S.

    2011-01-01

    Peroxidases have turned out to be potential biocatalyst for a variety of organic reactions. The research work reported in this communication was done with the objective of finding a convenient rich source of peroxidase which could be used as a biocatalyst for organic synthetic reactions. The studies made have shown that Luffa aegyptiaca (gourd) fruit juice contains peroxidase activity of the order of 180 enzyme unit/mL. The K m values of this peroxidase for the substrates guaiacol and hydroge...

  1. Effects of the hepatocarcinogen nafenopin, a peroxisome proliferator, on the activities of rat liver glutathione-requiring enzymes and catalase in comparison to the action of phenobarbital.

    Science.gov (United States)

    Furukawa, K; Numoto, S; Furuya, K; Furukawa, N T; Williams, G M

    1985-10-01

    The biochemical effects in the livers of male rats of prolonged administration of the experimental hepatocarcinogen nafenopin, a hypolipidemic agent and peroxisome proliferator, were compared to those of another experimental liver carcinogen, phenobarbital, which acts as a neoplasm promoter. Feeding of nafenopin, 0.03 mmol/kg basal diet for up to 24 weeks increased the numbers of hepatic peroxisomes, increased catalase activity, markedly decreased cytosolic glutathione transferase activities toward two substrates, decreased cytosolic glutathione peroxidase activities toward H2O2 and two organic peroxides, and suppressed the age-related increase in gamma-glutamyl transpeptidase activity. In contrast the livers of rats fed an equimolar concentration of phenobarbital displayed increases in cytosolic glutathione transferase activities and enhancement of gamma-glutamyl transpeptidase activity but no changes in glutathione peroxidase activities. There was also an enhancement of catalase activity without apparent increase in peroxisome number. Enzyme kinetic analyses revealed that the cytosolic glutathione transferase activities toward two halogenonitrobenzene substrates were inhibited in the rats fed nafenopin and displayed elevated Km and decreased Vmax. Kinetic studies of glutathione transferase activities in which nafenopin was mixed with normal rat liver cytosols in the assay system revealed competitive type inhibition toward 1-chloro-2,4-dinitrobenzene and a noncompetitive type of inhibition toward 3,4-dichloronitrobenzene. Likewise activities of glutathione peroxidases toward H2O2 and cumene hydroperoxide were suppressed by in vitro addition. Thus the effects of nafenopin and phenobarbital on liver biochemistry were very different. The inhibition of hepatic biotransformation and scavenger systems by nafenopin is suggested to be relevant to its hepatocarcinogenicity.

  2. Impaired glutathione synthesis in schizophrenia

    DEFF Research Database (Denmark)

    Gysin, René; Kraftsik, Rudolf; Sandell, Julie

    2007-01-01

    Schizophrenia is a complex multifactorial brain disorder with a genetic component. Convergent evidence has implicated oxidative stress and glutathione (GSH) deficits in the pathogenesis of this disease. The aim of the present study was to test whether schizophrenia is associated with a deficit...... of GSH synthesis. Cultured skin fibroblasts from schizophrenia patients and control subjects were challenged with oxidative stress, and parameters of the rate-limiting enzyme for the GSH synthesis, the glutamate cysteine ligase (GCL), were measured. Stressed cells of patients had a 26% (P = 0.......002) decreased GCL activity as compared with controls. This reduction correlated with a 29% (P schizophrenia in two...

  3. Comparative study of peroxidase purification from apple and orange ...

    African Journals Online (AJOL)

    This paper reports the isolation and purification of peroxidase from low cost material; moreover, no significant work has been done on the isolation and purification of peroxidase from such cost effective sources (apple and orange seeds). Peroxidases had attracted considerable interest in recent years because of their ...

  4. The diverse roles of glutathione-associated cell resistance against hypericin photodynamic therapy

    Directory of Open Access Journals (Sweden)

    Theodossis A. Theodossiou

    2017-08-01

    Full Text Available The diverse responses of different cancers to treatments such as photodynamic therapy of cancer (PDT have fueled a growing need for reliable predictive markers for treatment outcome. In the present work we have studied the differential response of two phenotypically and genotypically different breast adenocarcinoma cell lines, MCF7 and MDA-MB-231, to hypericin PDT (HYP-PDT. MDA-MB-231 cells were 70% more sensitive to HYP PDT than MCF7 cells at LD50. MCF7 were found to express a substantially higher level of glutathione peroxidase (GPX4 than MDA-MB-231, while MDA-MB-231 differentially expressed glutathione-S-transferase (GSTP1, mainly used for xenobiotic detoxification. Eighty % reduction of intracellular glutathione (GSH by buthionine sulfoximine (BSO, largely enhanced the sensitivity of the GSTP1 expressing MDA-MB-231 cells to HYP-PDT, but not in MCF7 cells. Further inhibition of the GSH reduction however by carmustine (BCNU resulted in an enhanced sensitivity of MCF7 to HYP-PDT. HYP loading studies suggested that HYP can be a substrate of GSTP for GSH conjugation as BSO enhanced the cellular HYP accumulation by 20% in MDA-MB-231 cells, but not in MCF7 cells. Studies in solutions showed that L-cysteine can bind the GSTP substrate CDNB in the absence of GSTP. This means that the GSTP-lacking MCF7 may use L-cysteine for xenobiotic detoxification, especially during GSH synthesis inhibition, which leads to L-cysteine build-up. This was confirmed by the lowered accumulation of HYP in both cell lines in the presence of BSO and the L-cysteine source NAC. NAC reduced the sensitivity of MCF7, but not MDA-MB-231, cells to HYP PDT which is in accordance with the antioxidant effects of L-cysteine and its potential as a GSTP substrate. As a conclusion we have herein shown that the different GSH based cell defense mechanisms can be utilized as predictive markers for the outcome of PDT and as a guide for selecting optimal combination strategies. Keywords

  5. Oxidative stress biomarkers in different tissues of rainbow trout (Oncorhynchus mykiss exposed to Disinfectant-CIP formulated with peracetic acid and hydrogen peroxide

    Directory of Open Access Journals (Sweden)

    Tkachenko Halyna

    2014-09-01

    Full Text Available The aim of study was to determine the effects of exposure to the product DEZYNFEKTANT-CIP (Eng. - Disinfectant-CIP, which is formulated with peracetic acid and hydrogen peroxide, on oxidative stress biomarkers (lipid peroxidation (LPO levels and the carbonyl content of oxidatively modified proteins and antioxidant defenses (superoxide dismutase (SOD, catalase (CAT, glutathione reductase (GR, glutathione peroxidase (GPx, total antioxidant capacity in muscle, gill, hepatic, and cardiac tissues of rainbow trout, Oncorhynchus mykiss (Walbaum. LPO and carbonyl contents changed with tissue type. Exposure to Disinfectant-CIP led to a significant decrease in LPO in muscle tissues and carbonyl content in muscle and gill tissues. The inhibition of SOD and CAT activity in muscle, hepatic, and cardiac tissues was observed probably because of increased oxidative stress during disinfection; however, hepatic and cardiac GPx activity increased in an attempt to counteract oxidative stress. We suggest that oxidative stress during the oxidation of peracetic acid and hydrogen peroxide could be counteracted by the antioxidant system in trout tissues. Correlative analysis between oxidative stress biomarkers and antioxidant defense confirms the pivotal role of SOD and CAT against CIP-induced oxidative stress

  6. Proteomic and activity profiles of ascorbate-glutathione cycle enzymes in germinating barley embryo

    DEFF Research Database (Denmark)

    Bønsager, Birgit Christine; Shahpiri, Azar; Finnie, Christine

    2010-01-01

    Enzymes involved in redox control are important during seed germination and seedling growth. Ascorbate-glutathione cycle enzymes in barley embryo extracts were monitored both by 2D-gel electrophoresis and activity measurements from 4 to 144 h post imbibition (PI). Strikingly different activity...... profiles were observed. No ascorbate peroxidase (APX) activity was present in mature seeds but activity was detected after 24 h PI and increased 14-fold up to 144 h PI. In contrast, dehydroascorbate reductase (DHAR) activity was present at 4 h PI and first decreased by 9-fold until 72 h PI followed by a 5......-fold increase at 144 h PI. Glutathione reductase and monodehydroascorbate reductase activities were also detected at 4 h PI, and showed modest increases of 1.8- and 2.7-fold, respectively, by 144 h PI. The combination of functional analysis with the proteomics approach enabled correlation...

  7. Mitochondrial Swelling Induced by Glutathione

    Science.gov (United States)

    Lehninger, Albert L.; Schneider, Marion

    1959-01-01

    Reduced glutathione, in concentrations approximating those occurring in intact rat liver, causes swelling of rat liver mitochondria in vitro which is different in kinetics and extent from that yielded by L-thyroxine. The effect is also given by cysteine, which is more active, and reduced coenzyme A, but not by L-ascorbate, cystine, or oxidized glutathione. The optimum pH is 6.5, whereas thyroxine-induced swelling is optimal at pH 7.5. The GSH-induced swelling is not inhibited by DNP or dicumarol, nor by high concentrations of sucrose, serum albumin, or polyvinylpyrrolidone, in contrast to thyroxine-induced swelling. ATP inhibits the GSH swelling, but ADP and AMP are ineffective. Mn-+ is a very potent inhibitor, but Mg++ is ineffective. Ethylenediaminetetraacetate is also an effective inhibitor of GSH-induced swelling. The respiratory inhibitors amytal and antimycin A do not inhibit the swelling action of GSH, but cyanide does; these findings are consistent with the view that the oxidation-reduction state of the respiratory chain between cytochrome c and oxygen is a determinant of GSH-induced swelling. Reversal of GSH-induced swelling by osmotic means or by ATP in KCl media could not be observed. Large losses of nucleotides and protein occur during the swelling by GSH, suggesting that the action is irreversible. The characteristically drastic swelling action of GSH could be prevented if L-thyroxine was also present in the medium. PMID:13630941

  8. Guaiacol peroxidase zymography for the undergraduate laboratory.

    Science.gov (United States)

    Wilkesman, Jeff; Castro, Diana; Contreras, Lellys M; Kurz, Liliana

    2014-01-01

    This laboratory exercise presents a novel way to introduce undergraduate students to the specific detection of enzymatic activity by electrophoresis. First, students prepare a crude peroxidase extract and then analyze the homogenate via electrophoresis. Zymography, that is, a SDS-PAGE method to detect enzyme activity, is used to specifically detect peroxidase activity and furthermore, to analyze the total protein profile. After the assay, students may estimate the apparent molecular mass of the enzyme and discuss its structure. After the 4-h experiment, students gain knowledge concerning biological sample preparation, gel preparation, electrophoresis, and the importance of specific staining procedures for the detection of enzymatic activity. Copyright © 2014 The International Union of Biochemistry and Molecular Biology.

  9. Functional analysis and localisation of a delta-class glutathione S-transferase from Sarcoptes scabiei.

    Science.gov (United States)

    Pettersson, Eva U; Ljunggren, Erland L; Morrison, David A; Mattsson, Jens G

    2005-01-01

    The mite Sarcoptes scabiei causes sarcoptic mange, or scabies, a disease that affects both animals and humans worldwide. Our interest in S. scabiei led us to further characterise a glutathione S-transferase. This multifunctional enzyme is a target for vaccine and drug development in several parasitic diseases. The S. scabiei glutathione S-transferase open reading frame reported here is 684 nucleotides long and yields a protein with a predicted molecular mass of 26 kDa. Through phylogenetic analysis the enzyme was classified as a delta-class glutathione S-transferase, and our paper is the first to report that delta-class glutathione S-transferases occur in organisms other than insects. The recombinant S. scabiei glutathione S-transferase was expressed in Escherichia coli via three different constructs and purified for biochemical analysis. The S. scabiei glutathione S-transferase was active towards the substrate 1-chloro-2,4-dinitrobenzene, though the positioning of fusion partners influenced the kinetic activity of the enzyme. Polyclonal antibodies raised against S. scabiei glutathione S-transferase specifically localised the enzyme to the integument of the epidermis and cavities surrounding internal organs in adult parasites. However, some minor staining of parasite intestines was observed. No staining was seen in host tissues, nor could we detect any antibody response against S. scabiei glutathione S-transferase in sera from naturally S. scabiei infected dogs or pigs. Additionally, the polyclonal sera raised against recombinant S. scabiei glutathione S-transferase readily detected a protein from mites, corresponding to the predicted size of native glutathione S-transferase.

  10. Determination of Glutathione and Its Redox Status in Isolated Vacuoles of Red Beetroot Cells

    Directory of Open Access Journals (Sweden)

    E.V. Pradedova

    2016-02-01

    Full Text Available The glutathione of the red beetroot vacuoles (Beta vulgaris L. was measured using three well-known methods: the spectrofluorimetric method with orthophthalic aldehyde (OPT; the spectrophotometric method with 5.5'-dithiobis-2-nitrobenzoic acid (DTNB; the high-performance liquid chromatography (HPLC. The content of reduced (GSH and oxidized glutathione (GSSG differed depending on the research method. With OPT the concentration of glutathione was: GSH – 0.059 µmol /mg protein; GSSG – 0.019 µmol/mg protein and total glutathione (GSHtotal – 0.097 µmol/mg protein. In the case of determining with DTNB the concentration of glutathione was: GSH – 0.091 µmol/mg protein; GSSG – 0.031 µmol/mg protein; GSHtotal – 0.153 µmol/mg protein. HPLC-defined concentration of glutathione was lower: GSH – 0.039 µmol/mg protein; GSSG – 0.007 µmol/mg protein; GSHtotal – 0.053 µmol/mg protein. Redox ratio of GSH/GSSG was also dependent on the method of determination: with OPT – 3.11; with DTNB – 2.96 and HPLC – 5.57. Redox ratio of glutathione in vacuoles was much lower than the tissue extracts of red beetroot, which, depending on the method of determination, was: 7.23, 7.16 and 9.22. The results showed the vacuoles of red beetroot parenchyma cells contain glutathione. Despite the low value of the redox ratio GSH/GSSG, in vacuoles the pool of reduced glutathione prevailed over the pool of oxidized glutathione.

  11. Experimental type 2 diabetes mellitus and acetaminophen toxic lesions: glutathione system indices changes

    Directory of Open Access Journals (Sweden)

    Olga Furka

    2017-11-01

    Full Text Available Background. The goal of the research was to study the effect of acetaminophen on major glutathione part of antioxidant system indices in liver homogenate of rats with type 2 diabetes mellitus in time dynamics. Materials and methods. We conducted two series of experiments. In the first series toxic lesion was caused by a single intragastric administration of acetaminophen suspension in 2 % starch solution to animals in a dose of 1250 mg/kg (1/2 LD50. In the second series  the suspension of acetaminophen in 2 % starch solution in a dose of 55 mg/kg was given, which corresponds to the highest therapeutic dose during 7 days. Non-genetic form of experimental type 2 diabetes mellitus was modeled by Islam S., Choi H. method (2007. Activity of glutathione peroxidase (GPx and glutathione reductase (GR, and contents of reduced glutathione (GSH were determined in liver homogenate. Results. The obtained results have shown that GR and GPx activity actively decreased after acetaminophen administration in higher therapeutic doses to rats with type 2 DM. However, the changes were less pronounced than in rats with type 2 DM and acute acetaminophen toxic lesions. Conclusion. Results of the research have shown that acetaminophen administration to rats with type 2 DM causes a significant violation of compensatory mechanisms, especially of the enzyme and nonenzyme parts of antioxidant system.

  12. Characterization of Affinity-Purified Isoforms of Acinetobacter calcoaceticus Y1 Glutathione Transferases

    Directory of Open Access Journals (Sweden)

    Chin-Soon Chee

    2014-01-01

    Full Text Available Glutathione transferases (GST were purified from locally isolated bacteria, Acinetobacter calcoaceticus Y1, by glutathione-affinity chromatography and anion exchange, and their substrate specificities were investigated. SDS-polyacrylamide gel electrophoresis revealed that the purified GST resolved into a single band with a molecular weight (MW of 23 kDa. 2-dimensional (2-D gel electrophoresis showed the presence of two isoforms, GST1 (pI 4.5 and GST2 (pI 6.2 with identical MW. GST1 was reactive towards ethacrynic acid, hydrogen peroxide, 1-chloro-2,4-dinitrobenzene, and trans,trans-hepta-2,4-dienal while GST2 was active towards all substrates except hydrogen peroxide. This demonstrated that GST1 possessed peroxidase activity which was absent in GST2. This study also showed that only GST2 was able to conjugate GSH to isoproturon, a herbicide. GST1 and GST2 were suggested to be similar to F0KLY9 (putative glutathione S-transferase and F0KKB0 (glutathione S-transferase III of Acinetobacter calcoaceticus strain PHEA-2, respectively.

  13. Characterization of Affinity-Purified Isoforms of Acinetobacter calcoaceticus Y1 Glutathione Transferases

    Science.gov (United States)

    Chee, Chin-Soon; Tan, Irene Kit-Ping; Alias, Zazali

    2014-01-01

    Glutathione transferases (GST) were purified from locally isolated bacteria, Acinetobacter calcoaceticus Y1, by glutathione-affinity chromatography and anion exchange, and their substrate specificities were investigated. SDS-polyacrylamide gel electrophoresis revealed that the purified GST resolved into a single band with a molecular weight (MW) of 23 kDa. 2-dimensional (2-D) gel electrophoresis showed the presence of two isoforms, GST1 (pI 4.5) and GST2 (pI 6.2) with identical MW. GST1 was reactive towards ethacrynic acid, hydrogen peroxide, 1-chloro-2,4-dinitrobenzene, and trans,trans-hepta-2,4-dienal while GST2 was active towards all substrates except hydrogen peroxide. This demonstrated that GST1 possessed peroxidase activity which was absent in GST2. This study also showed that only GST2 was able to conjugate GSH to isoproturon, a herbicide. GST1 and GST2 were suggested to be similar to F0KLY9 (putative glutathione S-transferase) and F0KKB0 (glutathione S-transferase III) of Acinetobacter calcoaceticus strain PHEA-2, respectively. PMID:24892084

  14. Enzyme Technology of Peroxidases: Immobilization, Chemical and Genetic Modification

    Science.gov (United States)

    Longoria, Adriana; Tinoco, Raunel; Torres, Eduardo

    An overview of enzyme technology applied to peroxidases is made. Immobilization on organic, inorganic, and hybrid supports; chemical modification of amino acids and heme group; and genetic modification by site-directed and random mutagenesis are included. Different strategies that were carried out to improve peroxidase performance in terms of stability, selectivity, and catalytic activity are analyzed. Immobilization of peroxidases on inorganic and organic materials enhances the tolerance of peroxidases toward the conditions normally found in many industrial processes, such as the presence of an organic solvent and high temperature. In addition, it is shown that immobilization helps to increase the Total Turnover Number at levels high enough to justify the use of a peroxidase-based biocatalyst in a synthesis process. Chemical modification of peroxidases produces modified enzymes with higher thermostability and wider substrate variability. Finally, through mutagenesis approaches, it is possible to produce modified peroxidases capable of oxidizing nonnatural substrates with high catalytic activity and affinity.

  15. Effects of dietary selenium on tissue concentrations,pathology, oxidative stress, and immune function in common eiders (Somateria mollissima)

    Science.gov (United States)

    Franson, J. Christian; Hoffman, David; Wells-Berlin, Alicia M.; Perry, Matthew C.; Shearn-Bochsler, Valerie I.; Finley, Daniel L.; Flint, Paul L.; Hollmén, Tuula E.

    2007-01-01

    Common eiders (Somateria mollissima) were fed added Se (as L-selenomethionine) in concentrations increasing from 10 to 80 ppm in a pilot study (Study 1) or 20 (low exposure) and up to 60 (high exposure) ppm Se in Study 2. Body weights of Study 1 ducks and high-exposure ducks in Study 2 declined rapidly. Mean concentrations of Se in blood reached 32.4 ppm wet weight in Study 1 and 17.5 ppm wet weight in high-exposure birds in Study 2. Mean Se concentrations in liver ranged from 351 (low exposure, Study 2) to 1252 ppm dry weight (Study 1). Oxidative stress was evidenced by Se-associated effects on glutathione metabolism. As Se concentrations in liver increased, Se-dependent glutathione peroxidase activity, glutathione reductase activity, oxidized glutathione levels, and the ratio of hepatic oxidized to reduced glutathione increased. In Study 2, the T-cell-mediated immune response was adversely affected in high-exposure eiders, but ducks in the low-exposure group exhibited evidence of an enhanced antibody-mediated immune response. Gross lesions in high-exposure ducks included emaciation, absence of thymus, and loss of nails from digits. Histologic lesions included severe depletion of lymphoid organs, hepatopathy, and necrosis of feather pulp and feather epithelium. Field studies showed that apparently healthy sea ducks generally have higher levels of Se in liver than healthy fresh-water birds, but lower than concentrations found in our study. Data indicate that common eiders and probably other sea ducks possess a higher threshold, or adverse effect level, for Se in tissues than fresh-water species. However, common eiders developed signs of Se toxicity similar to those seen in fresh-water birds.

  16. Glutathione, cell proliferation and differentiation | Ashtiani | African ...

    African Journals Online (AJOL)

    All organisms require an equivalent source for living. Reduced glutathione is the most abundant thiol containing protein in mammalian cells and organs. Glutathione was discovered by Hopkins in 1924 who published his findings in JBC. It is a three peptide containing glutamic acid, cystein and glycin and is found in reduced ...

  17. The Genetic Architecture of Murine Glutathione Transferases.

    Directory of Open Access Journals (Sweden)

    Lu Lu

    Full Text Available Glutathione S-transferase (GST genes play a protective role against oxidative stress and may influence disease risk and drug pharmacokinetics. In this study, massive multiscalar trait profiling across a large population of mice derived from a cross between C57BL/6J (B6 and DBA2/J (D2--the BXD family--was combined with linkage and bioinformatic analyses to characterize mechanisms controlling GST expression and to identify downstream consequences of this variation. Similar to humans, mice show a wide range in expression of GST family members. Variation in the expression of Gsta4, Gstt2, Gstz1, Gsto1, and Mgst3 is modulated by local expression QTLs (eQTLs in several tissues. Higher expression of Gsto1 in brain and liver of BXD strains is strongly associated (P < 0.01 with inheritance of the B6 parental allele whereas higher expression of Gsta4 and Mgst3 in brain and liver, and Gstt2 and Gstz1 in brain is strongly associated with inheritance of the D2 parental allele. Allele-specific assays confirmed that expression of Gsto1, Gsta4, and Mgst3 are modulated by sequence variants within or near each gene locus. We exploited this endogenous variation to identify coexpression networks and downstream targets in mouse and human. Through a combined systems genetics approach, we provide new insight into the biological role of naturally occurring variants in GST genes.

  18. A regulatory review for products containing glutathione

    Directory of Open Access Journals (Sweden)

    Nur Hidayah Abd Rahim

    2016-01-01

    Full Text Available Glutathione is a potent antioxidant as well as has important role for DNA synthesis and repair, protein synthesis, amino acid transport, and enzyme activation. Besides this, Glutathione products are now mainly selling as whitening agent which are mainly marketing through social media (Facebook and different websites. Information is not available whether glutathione product are following the regulatory guidelines of National Pharmaceutical Control Bureau of Malaysia (NPCB for selling, advertisement and promotion. This review was carried out by extracting information about glutathione from scientific database using PubMed, Cochrane Library and Embase. Analysis of the available information, case example of glutathione products showed that a brand of glutathione (Glutacaps HQ did not show the product's registration number from NPCB, and also did not show the name, address, contact number of the advertiser, and even not found the name of the manufacture. Without providing the above mentioned information, the product is selling and promoting through social media (fb which is not allowed by the NPCB guidelines part 4.14. So far, only two clinical trials were conducted on glutathione supplementation for 4 weeks duration. There was no serious or systematic adverse effects reported in clinical trials. As the two clinic trials resulted contradictory outcomes, further studies needed for conformation of the clinic benefits of glutathione. Otherwise, random use of glutathione may be risk for the health of the people. Besides, the marketer mainly promoting glutathione as the skin whitening beauty product instead of using as health supplement, it may cause additional and serious risk to the users as the manufacturer not providing sufficient information about the product, its registration number, manufacturing company, etc.

  19. Biomarker responsiveness in different tissues of caged Ruditapes philippinarum and its use within an integrated sediment quality assessment

    Energy Technology Data Exchange (ETDEWEB)

    Ramos-Gomez, Julia, E-mail: julia.ramosgomez@uca.es [UNITWIN/UNESCO/WiCoP, Departamento de Quimica Fisica, Universidad de Cadiz, Facultad de Ciencias del Mar y Ambientales, Campus Universitario de Puerto Real, 11510 Puerto Real, Cadiz (Spain); Coz, Alberto; Viguri, Javier R. [Dpto. Ingenieria Quimica y Quimica Inorganica, ETSIIT, Universidad de Cantabria, Avda. los Castros, s/n 39005 Santander (Spain); Luque, Angel [Departamento de Biologia, Universidad de Las Palmas de Gran Canaria, 35017 Las Palmas de Gran Canaria, Gran Canaria, The Canary Islands (Spain); Martin-Diaz, M. Laura [UNITWIN/UNESCO/WiCoP, Departamento de Quimica Fisica, Universidad de Cadiz, Facultad de Ciencias del Mar y Ambientales, Campus Universitario de Puerto Real, 11510 Puerto Real, Cadiz (Spain); Centro Andaluz de Ciencia y Tecnologia Marinas (CACYTMAR), Universidad de Cadiz, Campus Universitario de Puerto Real, 11510 Puerto Real, Cadiz (Spain); DelValls, T. Angel [UNITWIN/UNESCO/WiCoP, Departamento de Quimica Fisica, Universidad de Cadiz, Facultad de Ciencias del Mar y Ambientales, Campus Universitario de Puerto Real, 11510 Puerto Real, Cadiz (Spain)

    2011-07-15

    Biomarkers comprising activities of biotransformation enzymes (ethoxyresorufin-O-deethylase -EROD-, dibenzylfluorescein dealkylase -DBF-, glutathione S-transferase -GST), antioxidant enzymes (glutathione reductase -GR- and glutathione peroxidase -GPX), lipid peroxidation -LPO- and DNA strand breaks were analyzed in the clam Ruditapes philippinarum caged at Cadiz Bay, Santander Bay and Las Palmas de Gran Canaria (LPGC) Port (Spain). Sediments were characterized. Digestive gland was the most sensitive tissue to sediment contamination. In Cadiz Bay, changes in LPO regarding day 0 were related with metals. In LPGC Port, DBF, EROD, and GST activity responses suggested the presence of undetermined contaminants which might have led to DNA damage. In Santander Bay, PAHs were related with EROD activity, organic and metal contamination was found to be associated with GR and GST activities and DNA damage presented significant (p < 0.05) induction. R. philippinarum was sensitive to sediment contamination at biochemical level. Biomarkers allowed chemical exposure and sediment quality assessment. - Highlights: > Ruditapes philippinarum is sensitive to sediment contamination at biochemical level. > Digestive gland biomarkers showed the best correlations with sediment contaminants. > Presence of potentially toxic chemicals not analyzed in this research was unmasked. > Multivariate analysis allowed the identification of toxic xenobiotic and possible sources. > Inner area of Santander Bay presented the highest sediment toxicity. - Integration of Ruditapes philippinarum biomarker results and sediment chemistry distinguished xenobiotic exposure and sediment toxicity in coastal areas of Spain.

  20. Biomarker responsiveness in different tissues of caged Ruditapes philippinarum and its use within an integrated sediment quality assessment

    International Nuclear Information System (INIS)

    Ramos-Gomez, Julia; Coz, Alberto; Viguri, Javier R.; Luque, Angel; Martin-Diaz, M. Laura; DelValls, T. Angel

    2011-01-01

    Biomarkers comprising activities of biotransformation enzymes (ethoxyresorufin-O-deethylase -EROD-, dibenzylfluorescein dealkylase -DBF-, glutathione S-transferase -GST), antioxidant enzymes (glutathione reductase -GR- and glutathione peroxidase -GPX), lipid peroxidation -LPO- and DNA strand breaks were analyzed in the clam Ruditapes philippinarum caged at Cadiz Bay, Santander Bay and Las Palmas de Gran Canaria (LPGC) Port (Spain). Sediments were characterized. Digestive gland was the most sensitive tissue to sediment contamination. In Cadiz Bay, changes in LPO regarding day 0 were related with metals. In LPGC Port, DBF, EROD, and GST activity responses suggested the presence of undetermined contaminants which might have led to DNA damage. In Santander Bay, PAHs were related with EROD activity, organic and metal contamination was found to be associated with GR and GST activities and DNA damage presented significant (p < 0.05) induction. R. philippinarum was sensitive to sediment contamination at biochemical level. Biomarkers allowed chemical exposure and sediment quality assessment. - Highlights: → Ruditapes philippinarum is sensitive to sediment contamination at biochemical level. → Digestive gland biomarkers showed the best correlations with sediment contaminants. → Presence of potentially toxic chemicals not analyzed in this research was unmasked. → Multivariate analysis allowed the identification of toxic xenobiotic and possible sources. → Inner area of Santander Bay presented the highest sediment toxicity. - Integration of Ruditapes philippinarum biomarker results and sediment chemistry distinguished xenobiotic exposure and sediment toxicity in coastal areas of Spain.

  1. Immobilization of Peroxidase onto Magnetite Modified Polyaniline

    Directory of Open Access Journals (Sweden)

    Eduardo Fernandes Barbosa

    2012-01-01

    Full Text Available The present study describes the immobilization of horseradish peroxidase (HRP on magnetite-modified polyaniline (PANImG activated with glutaraldehyde. After the optimization of the methodology, the immobilization of HRP on PANImG produced the same yield (25% obtained for PANIG with an efficiency of 100% (active protein. The optimum pH for immobilization was displaced by the effect of the partition of protons produced in the microenvironment by the magnetite. The tests of repeated use have shown that PANImG-HRP can be used for 13 cycles with maintenance of 50% of the initial activity.

  2. Glutathione preservation during storage of rat lenses in optisol-GS and castor oil.

    Science.gov (United States)

    Holm, Thomas; Brøgger-Jensen, Martin Rocho; Johnson, Leif; Kessel, Line

    2013-01-01

    Glutathione concentration in the lens decreases in aging and cataractous lenses, providing a marker for tissue condition. Experimental procedures requiring unfrozen lenses from donor banks rely on transportation in storage medium, affecting lens homeostasis and alterations in glutathione levels. The aim of the study was to examine the effects of Optisol-GS and castor oil on lens condition, determined from their ability to maintain glutathione concentrations. Rat lenses were stored in the two types of storage media at varying time intervals up to 3 days. Glutathione concentration was afterwards determined in an enzymatic detection assay, specific for both reduced and oxidized forms. Lenses removed immediately after death exhibited a glutathione concentration of 4.70±0.29 mM. In vitro stored lenses in Optisol-GS lost glutathione quickly, ending with a concentration of 0.60±0.34 mM after 3 days while castor oil stored lenses exhibited a slower decline and ended at 3 times the concentration. A group of lenses were additionally stored under post mortem conditions within the host for 6 hours before its removal. Total glutathione after 6 hours was similar to that of lenses removed immediately after death, but with altered GSH and GSSG concentrations. Subsequent storage of these lenses in media showed changes similar to those in the first series of experiments, albeit to a lesser degree. It was determined that storage in Optisol-GS resulted in a higher loss of glutathione than lenses stored in castor oil. Storage for more than 12 hours reduced glutathione to half its original concentration, and was considered unusable after 24 hours.

  3. Glutathione preservation during storage of rat lenses in optisol-GS and castor oil.

    Directory of Open Access Journals (Sweden)

    Thomas Holm

    Full Text Available BACKGROUND: Glutathione concentration in the lens decreases in aging and cataractous lenses, providing a marker for tissue condition. Experimental procedures requiring unfrozen lenses from donor banks rely on transportation in storage medium, affecting lens homeostasis and alterations in glutathione levels. The aim of the study was to examine the effects of Optisol-GS and castor oil on lens condition, determined from their ability to maintain glutathione concentrations. METHODOLOGY/PRINCIPAL FINDINGS: Rat lenses were stored in the two types of storage media at varying time intervals up to 3 days. Glutathione concentration was afterwards determined in an enzymatic detection assay, specific for both reduced and oxidized forms. Lenses removed immediately after death exhibited a glutathione concentration of 4.70±0.29 mM. In vitro stored lenses in Optisol-GS lost glutathione quickly, ending with a concentration of 0.60±0.34 mM after 3 days while castor oil stored lenses exhibited a slower decline and ended at 3 times the concentration. A group of lenses were additionally stored under post mortem conditions within the host for 6 hours before its removal. Total glutathione after 6 hours was similar to that of lenses removed immediately after death, but with altered GSH and GSSG concentrations. Subsequent storage of these lenses in media showed changes similar to those in the first series of experiments, albeit to a lesser degree. CONCLUSIONS/SIGNIFICANCE: It was determined that storage in Optisol-GS resulted in a higher loss of glutathione than lenses stored in castor oil. Storage for more than 12 hours reduced glutathione to half its original concentration, and was considered unusable after 24 hours.

  4. Corneal endothelial glutathione after photodynamic change

    International Nuclear Information System (INIS)

    Hull, D.S.; Riley, M.V.; Csukas, S.; Green, K.

    1982-01-01

    Rabbit corneal endothelial cells perfused with 5 X 10(-6)M rose bengal and exposed to incandescent light demonstrated no alteration of either total of or percent oxidized glutathione after 1 hr. Addition of 5400 U/ml catalase to the perfusing solution had no effect on total glutathione levels but caused a marked reduction in percent oxidized glutathione in corneas exposed to light as well as in those not exposed to light. Substitution of sucrose for glucose in the perfusing solution had no effect on total or percent oxidized glutathione. Perfusion of rabbit corneal endothelium with 0.5 mM chlorpromazine and exposure to ultraviolet (UV) light resulted in no change in total glutathione content. A marked reduction in percent oxidized glutathione occurred, however, in corneas perfused with 0.5 mM chlorpromazine both in the presence and absence of UV light. It is concluded that photodynamically induced swelling of corneas is not the result of a failure of the glutathione redox system

  5. Glutathione in Cancer Cell Death

    Energy Technology Data Exchange (ETDEWEB)

    Ortega, Angel L. [Department of Physiology, Faculty of Medicine and Odontology, University of Valencia, 17 Av. Blasco Ibanez, 46010 Valencia (Spain); Mena, Salvador [Green Molecular SL, Pol. Ind. La Coma-Parc Cientific, 46190 Paterna, Valencia (Spain); Estrela, Jose M., E-mail: jose.m.estrela@uv.es [Department of Physiology, Faculty of Medicine and Odontology, University of Valencia, 17 Av. Blasco Ibanez, 46010 Valencia (Spain)

    2011-03-11

    Glutathione (L-γ-glutamyl-L-cysteinyl-glycine; GSH) in cancer cells is particularly relevant in the regulation of carcinogenic mechanisms; sensitivity against cytotoxic drugs, ionizing radiations, and some cytokines; DNA synthesis; and cell proliferation and death. The intracellular thiol redox state (controlled by GSH) is one of the endogenous effectors involved in regulating the mitochondrial permeability transition pore complex and, in consequence, thiol oxidation can be a causal factor in the mitochondrion-based mechanism that leads to cell death. Nevertheless GSH depletion is a common feature not only of apoptosis but also of other types of cell death. Indeed rates of GSH synthesis and fluxes regulate its levels in cellular compartments, and potentially influence switches among different mechanisms of death. How changes in gene expression, post-translational modifications of proteins, and signaling cascades are implicated will be discussed. Furthermore, this review will finally analyze whether GSH depletion may facilitate cancer cell death under in vivo conditions, and how this can be applied to cancer therapy.

  6. Colorimetric Glucose Assay Based on Magnetic Particles Having Pseudo-peroxidase Activity and Immobilized Glucose Oxidase.

    Science.gov (United States)

    Martinkova, Pavla; Opatrilova, Radka; Kruzliak, Peter; Styriak, Igor; Pohanka, Miroslav

    2016-05-01

    Magnetic particles (MPs) are currently used as a suitable alternative for peroxidase in the construction of novel biosensors, analytic and diagnostic methods. Their better chemical and thermal stabilities predestine them as appropriate pseudo-enzymatic catalysts. In this point of view, our research was focused on preparation of simply and fast method for immobilization of glucose oxidase onto surface of MPs with peroxidase-like activity. Spectrophotometric method (wavelength 450 nm) optimized for glucose determination using modified MPs has been successfully developed. Concentration curve for optimization of method was assayed, and Michaelis-Menten constant (K m) calculated, maximum reaction rate (V max), limit of detection, and correlation coefficient were determined to be 0.13 mmol/l (2.34 mg/dl), 1.79 pkat, 3.74 µmol/l (0.067 mg/dl), and 0.996, respectively. Interferences of other sugars such as sucrose, sorbitol, deoxyribose, maltose, and fructose were determined as well as effect of substances presenting in plasma (ascorbic acid, reduced glutathione, trolox, and urea). Results in comparison with positive and negative controls showed no interferences of the other sugars and no influence of plasma substances to measuring of glucose. The constructed method showed corresponding results with linear dependence and a correlation coefficient of 0.997. Possibility of repeated use of modified MPs was successfully proved.

  7. Andrographolide suppresses preadipocytes proliferation through glutathione antioxidant systems abrogation.

    Science.gov (United States)

    Chen, Wei; Su, Hongming; Feng, Lina; Zheng, Xiaodong

    2016-07-01

    Oxidative stress is considered to play a profound role in lipid storage and whole-body energy homeostasis. Inhibition of preadipocytes proliferation by natural products is one of the strategies to prevent obesity. Andrographolide, a small molecule, has been reported to possess versatile bioactivities. However, molecular mechanism underlying the potential effect of andrographolide on preadipocytes proliferation remains obscure. In the present study, 3T3-L1 preadipocytes were employed to determine whether andrographolide could affect the proliferation of preadipocytes. Our results demonstrated andrographolide suppressed 3T3-L1 preadipocytes proliferation. The casual relationship analysis indicated that andrographolide (10 and 20μg/ml) appeared to exert the proliferation inhibitory effect through suppression of glutathione peroxidase 1 (GPX1) activity and depleting GSH by promoting its efflux in 3T3-L1 preadipocytes, which subsequently resulted in 2.06-2.41 fold increase in ROS accumulation. Excessive ROS eruption could account for oxidative damage to mitochondrial membranes as well as ultimately inhibition of cell proliferation. Taken together, our study reveals that suppression of GPX1 and GSH depletion by andrographolide seems to play a critical role in the inhibition of 3T3-L1 preadipocytes proliferation, which might have implication for obesity prevention and treatment. Copyright © 2016 Elsevier Inc. All rights reserved.

  8. Dependency of a therapy-resistant state of cancer cells on a lipid peroxidase pathway.

    Science.gov (United States)

    Viswanathan, Vasanthi S; Ryan, Matthew J; Dhruv, Harshil D; Gill, Shubhroz; Eichhoff, Ossia M; Seashore-Ludlow, Brinton; Kaffenberger, Samuel D; Eaton, John K; Shimada, Kenichi; Aguirre, Andrew J; Viswanathan, Srinivas R; Chattopadhyay, Shrikanta; Tamayo, Pablo; Yang, Wan Seok; Rees, Matthew G; Chen, Sixun; Boskovic, Zarko V; Javaid, Sarah; Huang, Cherrie; Wu, Xiaoyun; Tseng, Yuen-Yi; Roider, Elisabeth M; Gao, Dong; Cleary, James M; Wolpin, Brian M; Mesirov, Jill P; Haber, Daniel A; Engelman, Jeffrey A; Boehm, Jesse S; Kotz, Joanne D; Hon, Cindy S; Chen, Yu; Hahn, William C; Levesque, Mitchell P; Doench, John G; Berens, Michael E; Shamji, Alykhan F; Clemons, Paul A; Stockwell, Brent R; Schreiber, Stuart L

    2017-07-27

    Plasticity of the cell state has been proposed to drive resistance to multiple classes of cancer therapies, thereby limiting their effectiveness. A high-mesenchymal cell state observed in human tumours and cancer cell lines has been associated with resistance to multiple treatment modalities across diverse cancer lineages, but the mechanistic underpinning for this state has remained incompletely understood. Here we molecularly characterize this therapy-resistant high-mesenchymal cell state in human cancer cell lines and organoids and show that it depends on a druggable lipid-peroxidase pathway that protects against ferroptosis, a non-apoptotic form of cell death induced by the build-up of toxic lipid peroxides. We show that this cell state is characterized by activity of enzymes that promote the synthesis of polyunsaturated lipids. These lipids are the substrates for lipid peroxidation by lipoxygenase enzymes. This lipid metabolism creates a dependency on pathways converging on the phospholipid glutathione peroxidase (GPX4), a selenocysteine-containing enzyme that dissipates lipid peroxides and thereby prevents the iron-mediated reactions of peroxides that induce ferroptotic cell death. Dependency on GPX4 was found to exist across diverse therapy-resistant states characterized by high expression of ZEB1, including epithelial-mesenchymal transition in epithelial-derived carcinomas, TGFβ-mediated therapy-resistance in melanoma, treatment-induced neuroendocrine transdifferentiation in prostate cancer, and sarcomas, which are fixed in a mesenchymal state owing to their cells of origin. We identify vulnerability to ferroptic cell death induced by inhibition of a lipid peroxidase pathway as a feature of therapy-resistant cancer cells across diverse mesenchymal cell-state contexts.

  9. Sequence and RT-PCR expression analysis of two peroxidases from Arabidopsis thaliana belonging to a novel evolutionary branch of plant peroxidases.

    Science.gov (United States)

    Kjaersgård, I V; Jespersen, H M; Rasmussen, S K; Welinder, K G

    1997-03-01

    ; (2) an N-glycosylation site is located right at the entrance to the heme channel. The reverse transcriptase polymerase chain reaction (RT-PCR) was used to identify mRNAs coding for ATP 1a/b and ATP 2a/b in germinating seeds, seedlings, roots, leaves, stems, flowers and cell suspension culture using elongation factor 1alpha (EF-1alpha) for the first time as a positive control. Both mRNAs were transcribed at levels comparable to EF-1alpha in all plant tissues investigated which were more than two days old, and in cell suspension culture. In addition, the mRNA coding for ATP 1a/b was found in two day old germinating seeds. The abundant transcription of ATP 1a/b and ATP 2a/b is in line with their many entries in dbEST, and indicates essential roles for these novel peroxidases.

  10. Ascorbate Peroxidase and Catalase Activities and Their Genetic Regulation in Plants Subjected to Drought and Salinity Stresses

    Directory of Open Access Journals (Sweden)

    Adriano Sofo

    2015-06-01

    Full Text Available Hydrogen peroxide (H2O2, an important relatively stable non-radical reactive oxygen species (ROS is produced by normal aerobic metabolism in plants. At low concentrations, H2O2 acts as a signal molecule involved in the regulation of specific biological/physiological processes (photosynthetic functions, cell cycle, growth and development, plant responses to biotic and abiotic stresses. Oxidative stress and eventual cell death in plants can be caused by excess H2O2 accumulation. Since stress factors provoke enhanced production of H2O2 in plants, severe damage to biomolecules can be possible due to elevated and non-metabolized cellular H2O2. Plants are endowed with H2O2-metabolizing enzymes such as catalases (CAT, ascorbate peroxidases (APX, some peroxiredoxins, glutathione/thioredoxin peroxidases, and glutathione sulfo-transferases. However, the most notably distinguished enzymes are CAT and APX since the former mainly occurs in peroxisomes and does not require a reductant for catalyzing a dismutation reaction. In particular, APX has a higher affinity for H2O2 and reduces it to H2O in chloroplasts, cytosol, mitochondria and peroxisomes, as well as in the apoplastic space, utilizing ascorbate as specific electron donor. Based on recent reports, this review highlights the role of H2O2 in plants experiencing water deficit and salinity and synthesizes major outcomes of studies on CAT and APX activity and genetic regulation in drought- and salt-stressed plants.

  11. Purification, molecular cloning and heterologous expression of a glutathione S-transferase involved in insecticide resistance from the rice brown planthopper, Nilaparvata lugens.

    OpenAIRE

    Vontas, John G; Small, Graham J; Nikou, Dimitra C; Ranson, Hilary; Hemingway, Janet

    2002-01-01

    A novel glutathione S-transferase (GST)-based pyrethroid resistance mechanism was recently identified in Nilaparvata lugens [Vontas, Small and Hemingway (2001) Biochem. J. 357, 65-72]. To determine the nature of GSTs involved in conferring this resistance, the GSTs from resistant and susceptible strains of N. lugens were partially purified by anion exchange and affinity chromatography. The majority of peroxidase activity, previously correlated with resistance, was confined to the fraction tha...

  12. Prenatal methylmercury exposure hampers glutathione antioxidant system ontogenesis and causes long-lasting oxidative stress in the mouse brain

    International Nuclear Information System (INIS)

    Stringari, James; Nunes, Adriana K.C.; Franco, Jeferson L.; Bohrer, Denise; Garcia, Solange C.; Dafre, Alcir L.; Milatovic, Dejan; Souza, Diogo O.; Rocha, Joao B.T.; Aschner, Michael; Farina, Marcelo

    2008-01-01

    During the perinatal period, the central nervous system (CNS) is extremely sensitive to metals, including methylmercury (MeHg). Although the mechanism(s) associated with MeHg-induced developmental neurotoxicity remains obscure, several studies point to the glutathione (GSH) antioxidant system as an important molecular target for this toxicant. To extend our recent findings of MeHg-induced GSH dyshomeostasis, the present study was designed to assess the developmental profile of the GSH antioxidant system in the mouse brain during the early postnatal period after in utero exposure to MeHg. Pregnant mice were exposed to different doses of MeHg (1, 3 and 10 mg/l, diluted in drinking water, ad libitum) during the gestational period. After delivery, pups were killed at different time points - postnatal days (PND) 1, 11 and 21 - and the whole brain was used for determining biochemical parameters related to the antioxidant GSH system, as well as mercury content and the levels of F 2 -isoprostane. In control animals, cerebral GSH levels significantly increased over time during the early postnatal period; gestational exposure to MeHg caused a dose-dependent inhibition of this developmental event. Cerebral glutathione peroxidase (GPx) and glutathione reductase (GR) activities significantly increased over time during the early postnatal period in control animals; gestational MeHg exposure induced a dose-dependent inhibitory effect on both developmental phenomena. These adverse effects of prenatal MeHg exposure were corroborated by marked increases in cerebral F 2 -isoprostanes levels at all time points. Significant negative correlations were found between F 2 -isoprostanes and GSH, as well as between F 2 -isoprostanes and GPx activity, suggesting that MeHg-induced disruption of the GSH system maturation is related to MeHg-induced increased lipid peroxidation in the pup brain. In utero MeHg exposure also caused a dose-dependent increase in the cerebral levels of mercury at

  13. Measurement of glutathione-protein mixed disulfides

    International Nuclear Information System (INIS)

    Livesey, J.C.; Reed, D.J.

    1984-01-01

    The development of a sensitive and highly specific assay for the presence of mixed disulfides between protein thiol groups and endogenous thiols has been undertaken. Previous investigations on the concentrations of glutathione (GSH), glutathione disulfide (GSSG) and protein glutathione mixed disulfides (ProSSG) have been of limited usefulness because of the poor specificity of the assays used. Our assay for these forms of glutathione is based on high performance liquid chromatography (HPLC) and is an extension of an earlier method. After perchloric acid precipitation, the protein sample is washed with an organic solvent to fully denature the protein. Up to a 10-fold increase in GSH released from fetal bovine serum (FBS) protein has been found when the protein precipitate is washed with ethanol rather than ether, as earlier suggested. Similar effects have been observed with an as yet unidentified thiol which elutes in the chromatography system with a retention volume similar to cysteine

  14. Glutathione Metabolism and Parkinson’s Disease

    OpenAIRE

    Smeyne, Michelle; Smeyne, Richard Jay

    2013-01-01

    It has been established that oxidative stress, defined as the condition when the sum of free radicals in a cell exceeds the antioxidant capacity of the cell, contributes to the pathogenesis of Parkinson’s disease. Glutathione is a ubiquitous thiol tripeptide that acts alone, or in concert with enzymes within cells to reduce superoxide radicals, hydroxyl radicals and peroxynitrites. In this review, we examine the synthesis, metabolism and functional interactions of glutathione, and discuss how...

  15. Oxidative degradation of alkylphenols by horseradish peroxidase.

    Science.gov (United States)

    Sakuyama, Hisae; Endo, Yasushi; Fujimoto, Kenshiro; Hatana, Yasuhiko

    2003-01-01

    Alkylphenols such as bisphenol A (2,2-bis(4-hydroxyphenyl)propane; BPA), p-nonylphenol (p-NP), and p-octylphenol (p-OP) that are known as endocrine disrupters were oxidized by horseradish (Armoracia rusticana) peroxidase (HRP) with H2O2. The optimal pHs for BPA, p-NP, and p-OP were 8.0, 7.0, and 5.0, respectively. The optimal temperature for BPA was 20 degrees C. Although BPA was rapidly degraded by HRP, its degradation depended on the concentration of HRP. Most of the oxidation products of BPA were polymers, although some 4-isopropenylphenol was produced. When male Japanese medaka (Oryzias latipes) were exposed to BPA, vitellogenin in the blood increased. However, no increased vitellogenin was observed in medaka exposed to HRP-oxidized BPA. The enzymatic oxidation of BPA using HRP was able to eliminate its estrogen-like activity.

  16. Apple and quince peroxidase activity in response to essential oils ...

    African Journals Online (AJOL)

    Enzymatic browning arises by peroxidase in fruits. However, essential oils are recognized as natural antioxidant agents. So in this study, the effect of thyme, coriander and rosemary essential oils were evaluated on the reduction of peroxidase activity in apples (Malus domestica Mill. cv Golden delicious), (M. domestica Mill.

  17. Cloning and analysis of the ascorbate peroxidase gene promoter ...

    African Journals Online (AJOL)

    Ascorbate peroxidase (APX) is known to catalyze the reduction of H2O2 to water and enhance plants' tolerance in stress environment. An ascorbate peroxidase protein (BnAPX) was previously isolated from Brassica napus in our laboratory and it was located in the chloroplast. In order to clarify the physiological function of ...

  18. Production of lignin peroxidase by Ganoderma leucidum using solid ...

    African Journals Online (AJOL)

    The main objectives of this study were to optimize the culture conditions for the production of lignin peroxidase by Ganoderma leucidum, economic utilization of waste corn cobs as inducers substrate by pollution free fermentation technology and to optimize the solid state fermentation (SSF) process for lignin peroxidase ...

  19. Heat stable peroxidases from Vigna species (V) | Mbassi | African ...

    African Journals Online (AJOL)

    Shoots of three landraces of a Vigna species from two climatic areas of Cameroon were evaluated for their content of heat-resistant peroxidases. The peroxidase activity in the three landraces was detected with a greater catalytic efficiency for oxidation of O-dianisidine relative to ABTS (2, 2'-azino-bis-(3- ...

  20. The relationship between lignin peroxidase and manganese peroxidase production capacities and cultivation periods of mushrooms.

    Science.gov (United States)

    Xu, Jian Z; Zhang, Jun L; Hu, Kai H; Zhang, Wei G

    2013-05-01

    Mushrooms are able to secrete lignin peroxidase (LiP) and manganese peroxidase (MnP), and able to use the cellulose as sources of carbon. This article focuses on the relation between peroxidase-secreting capacity and cultivation period of mushrooms with non-laccase activity. Methylene blue and methyl catechol qualitative assay and spectrophotometry quantitative assay show LiP secreting unvaryingly accompanies the MnP secreting in mushroom strains. The growth rates of hyphae are detected by detecting the dry hyphal mass. We link the peroxidase activities to growth rate of mushrooms and then probe into the relationship between them. The results show that there are close relationships between LiP- and/or MnP-secretory capacities and the cultivation periods of mushrooms. The strains with high LiP and MnP activities have short cultivation periods. However, those strains have long cultivation periods because of the low levels of secreted LiP and/or MnP, even no detectable LiP and/or MnP activity. This study provides the first evidence on the imitate relation between the level of secreted LiP and MnP activities and cultivation periods of mushrooms with non-laccase activity. Our study has significantly increased the understanding of the role of LiP and MnP in the growth and development of mushrooms with non-laccase activity. © 2012 The Authors. Microbial Biotechnology © 2012 Society for Applied Microbiology and Blackwell Publishing Ltd.

  1. Purification, characterization and stability of barley grain peroxidase BP1, a new type of plant peroxidase

    DEFF Research Database (Denmark)

    Rasmussen, Christine B; Henriksen, Anette; Abelskov, A. Katrine

    1997-01-01

    peroxidase isoenzyme C (HRP C). However, when measuring the specific activity of BP 1 at pH 4.0 in the presence of 1 mM CaCl2, the enzyme was as competent as HRP C at neutral pH towards a variety of substrates (mM mg(-1) min(-1)): coniferyl alcohol (930+/-48), caffeic acid (795+/-53), ABTS (2,2(1)-azino...

  2. Luffa aegyptiaca (Gourd) Fruit Juice as a Source of Peroxidase.

    Science.gov (United States)

    Yadav, R S S; Yadav, K S; Yadav, H S

    2011-01-01

    Peroxidases have turned out to be potential biocatalyst for a variety of organic reactions. The research work reported in this communication was done with the objective of finding a convenient rich source of peroxidase which could be used as a biocatalyst for organic synthetic reactions. The studies made have shown that Luffa aegyptiaca (gourd) fruit juice contains peroxidase activity of the order of 180 enzyme unit/mL. The K(m) values of this peroxidase for the substrates guaiacol and hydrogen peroxide were 2.0 and 0.2 mM, respectively. The pH and temperature optima were 6.5 and 60°C, respectively. Like other peroxidases, it followed double displacement type mechanism. Sodium azide inhibited the enzyme competitively with K(i) value of 3.35 mM.

  3. Luffa aegyptiaca (Gourd Fruit Juice as a Source of Peroxidase

    Directory of Open Access Journals (Sweden)

    R. S. S. Yadav

    2011-01-01

    Full Text Available Peroxidases have turned out to be potential biocatalyst for a variety of organic reactions. The research work reported in this communication was done with the objective of finding a convenient rich source of peroxidase which could be used as a biocatalyst for organic synthetic reactions. The studies made have shown that Luffa aegyptiaca (gourd fruit juice contains peroxidase activity of the order of 180 enzyme unit/mL. The Km values of this peroxidase for the substrates guaiacol and hydrogen peroxide were 2.0 and 0.2 mM, respectively. The pH and temperature optima were 6.5 and 60°C, respectively. Like other peroxidases, it followed double displacement type mechanism. Sodium azide inhibited the enzyme competitively with Ki value of 3.35 mM.

  4. Formation of a tyrosine adduct involved in lignin degradation by Trametopsis cervina lignin peroxidase: a novel peroxidase activation mechanism

    Science.gov (United States)

    Yuta Miki; Rebecca Pogni; Sandra Acebes; Fatima Lucas; Elena Fernandez-Fueyo; Maria Camilla Baratto; Maria I. Fernandez; Vivian De Los Rios; Francisco J. Ruiz-duenas; Adalgisa Sinicropi; Riccardo Basosi; Kenneth E. Hammel; Victor Guallar; Angel T. Martinez

    2013-01-01

    LiP (lignin peroxidase) from Trametopsis cervina has an exposed catalytic tyrosine residue (Tyr181) instead of the tryptophan conserved in other lignin-degrading peroxidases. Pristine LiP showed a lag period in VA (veratryl alcohol) oxidation. However, VA-LiP (LiP after treatment with H2O2...

  5. Involvement of human glutathione S-transferase isoenzymes in the conjugation of cyclophosphamide metabolites with glutathione

    NARCIS (Netherlands)

    Dirven, H.A.A.M.; Ommen, B. van; Bladeren, P.J. van

    1994-01-01

    Alkylating agents can be detoxified by conjugation with glutathione (GSH). One of the physiological significances of this lies in the observation that cancer cells resistant to the cytotoxic effects of alkylating agents have higher levels of GSH and high glutathione S-transferase (GST) activity.

  6. Relations between metals (Zn, Pb, Cd and Cu) and glutathione-dependent detoxifying enzymes in spiders from a heavy metal pollution gradient

    International Nuclear Information System (INIS)

    Wilczek, Grazyna; Babczynska, Agnieszka; Augustyniak, Maria; Migula, Pawel

    2004-01-01

    We studied the relations between glutathione-dependent detoxifying enzymes and heavy metal burdens in the web-building spider Agelena labyrinthica (Agelenidae) and the wolf spider Pardosa lugubris (Lycosidae) from five meadow sites along a heavy metal pollution gradient. We assayed the activity of glutathione-S-transferase (GST) and glutathione peroxidases (GPOX, GSTPx), and glutathione (GSH) levels in both sexes. Except for GSH vs Pb content, we found significant correlations between GPOX and GSTPx activity and metal concentrations in females of A. labyrinthica. The highest activity of these enzymes measured in the web-building spiders was found in the individuals from the most polluted sites. In P. lugubris males significant correlations were found between GST and Pb and Zn concentrations, and between GPOX and GSTPx and the concentration of Cu. GST activity was higher in males collected from less polluted areas. Thus, detoxifying strategies against pollutants seemed to be sex-dependent. Actively hunting spiders had higher metal concentrations, maintaining lower activity of detoxifying enzymes and a lower glutathione level. - Capsule: Glutathione-linked enzyme activity in spiders from polluted areas depends on hunting strategy and sex

  7. Relations between metals (Zn, Pb, Cd and Cu) and glutathione-dependent detoxifying enzymes in spiders from a heavy metal pollution gradient

    Energy Technology Data Exchange (ETDEWEB)

    Wilczek, Grazyna [Department of Animal Physiology and Ecotoxicology, University of Silesia, Bankowa 9, 40-007 Katowice (Poland); Babczynska, Agnieszka [Department of Animal Physiology and Ecotoxicology, University of Silesia, Bankowa 9, 40-007 Katowice (Poland); Augustyniak, Maria [Department of Animal Physiology and Ecotoxicology, University of Silesia, Bankowa 9, 40-007 Katowice (Poland); Migula, Pawel [Department of Animal Physiology and Ecotoxicology, University of Silesia, Bankowa 9, 40-007 Katowice (Poland)]. E-mail: migula@us.edu.pl

    2004-12-01

    We studied the relations between glutathione-dependent detoxifying enzymes and heavy metal burdens in the web-building spider Agelena labyrinthica (Agelenidae) and the wolf spider Pardosa lugubris (Lycosidae) from five meadow sites along a heavy metal pollution gradient. We assayed the activity of glutathione-S-transferase (GST) and glutathione peroxidases (GPOX, GSTPx), and glutathione (GSH) levels in both sexes. Except for GSH vs Pb content, we found significant correlations between GPOX and GSTPx activity and metal concentrations in females of A. labyrinthica. The highest activity of these enzymes measured in the web-building spiders was found in the individuals from the most polluted sites. In P. lugubris males significant correlations were found between GST and Pb and Zn concentrations, and between GPOX and GSTPx and the concentration of Cu. GST activity was higher in males collected from less polluted areas. Thus, detoxifying strategies against pollutants seemed to be sex-dependent. Actively hunting spiders had higher metal concentrations, maintaining lower activity of detoxifying enzymes and a lower glutathione level. - Capsule: Glutathione-linked enzyme activity in spiders from polluted areas depends on hunting strategy and sex.

  8. The glutathione cycle: Glutathione metabolism beyond the γ-glutamyl cycle.

    Science.gov (United States)

    Bachhawat, Anand Kumar; Yadav, Shambhu

    2018-04-17

    Glutathione was discovered in 1888, over 125 years ago. Since then, our understanding of various functions and metabolism of this important molecule has grown over these years. But it is only now, in the last decade, that a somewhat complete picture of its metabolism has emerged. Glutathione metabolism has till now been largely depicted and understood by the γ-glutamyl cycle that was proposed in 1970. However, new findings and knowledge particularly on the transport and degradation of glutathione have revealed that many aspects of the γ-glutamyl cycle are incorrect. Despite this, an integrated critical analysis of the cycle has never been undertaken and this has led to the cycle and its errors perpetuating in the literature. This review takes a careful look at the γ-glutamyl cycle and its shortcomings and presents a "glutathione cycle" that captures the current understanding of glutathione metabolism. © 2018 IUBMB Life, 2018. © 2018 International Union of Biochemistry and Molecular Biology.

  9. Retraction Note: The effects of valsartan on renal glutathione peroxidase expression in alleviation of cyclosporine nephrotoxicity in rats

    Directory of Open Access Journals (Sweden)

    Sina Raeisi

    2016-12-01

    As a peer-review multidisciplinary international "Publish Free" and "Access Free" journal, BioImpacts strongly adheres to the "Publication Ethics", and its foremost goal is to preserve the integrity of the scientific reports in the highest standards, therefore the journal takes all issues of publication misconduct seriously.

  10. Study of antioxidant enzymes superoxide dismutase and glutathione peroxidase levels in tobacco chewers and smokers: A pilot study

    Directory of Open Access Journals (Sweden)

    Chundru Venkata Naga Sirisha

    2013-01-01

    Conclusions: The present study gave us an insight about the relationship between antioxidant enzyme activity, oxidative stress and tobacco. The altered antioxidant enzyme levels observed in this study will act as a predictor for pre potentially malignant lesions. Therefore an early intervention of tobacco habit and its related oxidative stress would prevent the development of tobacco induced lesions.

  11. The effect of sesamine and aerobic exercise on plasma levels of total antioxidant capacity and glutathione peroxidase in athlete men

    Directory of Open Access Journals (Sweden)

    Yousef Saberi

    2017-10-01

    Conclusion: Aerobic exercise and supplementation of sesamin is an effective method to improve the health of mens athlete's immune system. In addition, combining supplementation with aerobic exercise can increase some of the beneficial effects of exercise during a 10-week period.

  12. Changes of superoxide dismutase, catalase and glutathione peroxidase in the corneal epithelium after UVB rays. Histochemical and biochemical study

    Czech Academy of Sciences Publication Activity Database

    Čejková, Jitka; Štípek, S.; Crkovská, J.; Ardan, Taras

    2000-01-01

    Roč. 15, - (2000), s. 1043-1050 ISSN 0213-3911 R&D Projects: GA MZd NG16; GA ČR GV307/96/K226 Institutional research plan: CEZ:AV0Z5039906 Subject RIV: FF - HEENT, Dentistry Impact factor: 1.553, year: 2000

  13. Thioredoxin 1 in Prostate Tissue Is Associated with Gleason Score, Erythrocyte Antioxidant Enzyme Activity, and Dietary Antioxidants

    Directory of Open Access Journals (Sweden)

    Terrence M. Vance

    2015-01-01

    Full Text Available Background. Prostate cancer is the most common noncutaneous cancer and second leading cause of cancer-related mortality in men in the US. Growing evidence suggests that oxidative stress is involved in prostate cancer. Methods. In this study, thioredoxin 1 (Trx 1, an enzyme and subcellular indicator of redox status, was measured in prostate biopsy tissue from 55 men from the North Carolina-Louisiana Prostate Cancer Project. A pathologist blindly scored levels of Trx 1. The association between Trx 1 and the Gleason score, erythrocyte antioxidant enzyme activity, and dietary antioxidant intake was determined using Fisher’s exact test. Results. Trx 1 levels in benign prostate tissue in men with incident prostate cancer were positively associated with the Gleason score (P=0.01 and inversely associated with dietary antioxidant intake (P=0.03. In prostate cancer tissue, Trx 1 levels were associated with erythrocyte glutathione peroxidase activity (P=0.01. No association was found for other erythrocyte enzymes. Greater Gleason score of malignant tissue corresponds to a greater difference in Trx 1 levels between malignant and benign tissue (P=0.04. Conclusion. These results suggest that the redox status of prostate tissue is associated with prostate cancer grade and both endogenous and exogenous antioxidants.

  14. Probucol Attenuates Cyclophosphamide-induced Oxidative Apoptosis, p53 and Bax Signal Expression in Rat Cardiac Tissues

    Directory of Open Access Journals (Sweden)

    Yousif A. Asiri

    2010-01-01

    Full Text Available Cyclophosphamide (CP is a widely used drug in cancer chemotherapy and immunosuppression, which could cause toxicity of the normal cells due to its toxic metabolites. Probucol, a cholesterol-lowering drug, acts as potential inhibitor of DNA damage and shows to protect against doxorubicin-induced cardiomyopathy by enhancing the endogenous antioxidant system including glutathione peroxidase, catalase and superoxide dismutase. This study examined the possible protective effects of probucol, a lipid-lowering compound with strong antioxidant properties, against CPinduced cardiotoxicity. This objective could be achieved through studying the gene expression-based on the possible protective effects of probucol against CP-induced cardiac failure in rats. Adult male Wistar albino rats were assigned into four treatment groups: Animals in the first (control and second (probucol groups were injected intraperitoneally with corn oil and probucol (61 mg/kg/day, respectively, for two weeks. Animals in the third (CP and fourth (probucol plus CP groups were injected with the same doses of corn oil and probucol (61 mg/kg/day, respectively, for one week before and one week after a single dose of CP (200 mg/kg, I.P.. The p53, Bax, Bcl2 and oxidative genes signal expression were measured by real time PCR. CP-induced cardiotoxicity was clearly observed by a significant increase in serum creatine phosphokinase isoenzyme (CK-MB (117%, lactate dehydrogenase (LDH (64%, free (69% and esterified cholesterol (42% and triglyceride (69% compared to control group. In cardiac tissues, CP significantly increases the mRNA expression levels of apoptotic genes, p53 with two-fold and Bax with 1.6-fold, and decreases the anti-apoptotic gene Bcl2 with 0.5-fold. Moreover, CP caused downregulation of antioxidant genes, glutathione peroxidase, catalase, and superoxide dismutase and increased the lipid peroxidation and decreased adenosine triphosphate (ATP (40% and ATP/ADP (44% in cardiac

  15. Efficacy of glutathione mesotherapy in burns: an experimental study.

    Science.gov (United States)

    Buz, A; Görgülü, T; Olgun, A; Kargi, E

    2016-12-01

    Thermal burns are the leading cause of trauma worldwide. Currently, no consensus on optimal treatment of deep partial-thickness (second-degree) burns has emerged, as reflected by the wide variability in available wound-care materials. The relative efficacies of products used for treatment of partial-thickness thermal burns remain unclear. Mesotherapy features intradermal administration of various agents, depending on burn location. In the present experimental study, we explored the efficacy of mesotherapy used to treat partial-thickness thermal burns in 50 male Wistar rats divided into five groups of equal number. No procedure was performed after infliction of thermal burns in control group (Group 1). Mesotherapy was applied with physiological saline in sham group (Group 2), glutathione, taurine, and L-carnitine were separately applied in Group 3, Group 4, and Group 5, respectively. Mesotherapeutic agents were injected intradermally into the reticular layer of the dermis using the point technique. The first course of mesotherapy was given within the first 2 h after infliction of thermal burns, and therapy was continued to day 10. On day 22, unhealed thermal burn areas were measured prior to sacrifice, and biopsies covering the total areas of burns were performed to allow of pathological evaluation. Group 3 (the glutathione group) showed the best extent of healing, followed by Group 4 (the taurine group) and Group 5 (the L-carnitine group). The healed thermal burn areas in these groups were significantly greater than those in the control and sham groups (P = 0.001). All of healing, acute and chronic inflammation, the amount of granulation tissue, the level of fibroblast maturation, the amount of collagen, the extent of re-epithelization and neovascularization, and ulcer depth were scored upon pathological examination of tissue cross-sections. The best outcomes were evident in the glutathione group, with statistical significance. Although wound healing in the L

  16. Production and Purification of Peroxidase from Aspergillus niger.

    Directory of Open Access Journals (Sweden)

    Mohammed A. Jebor

    2017-02-01

    Full Text Available This study was conducted in the laboratories of Biology Department, College of Science, which deals with isolation and purification of peroxidase and optimization of process parameters to achieve maximum yield of peroxidase by Aspergillus niger. Solid-state fermentation of Aspergillus niger was carried out for enhanced production of peroxidase using hydrogen peroxide as the substrate of enzyme maximum activity of the enzyme was achieved under optimum growth conditions. The optimum conditions were the isolated of Aspergillus niger from soil and growth in synthetic medium, it gave high titer of peroxidase activity, the fructose as carbon source, peptone as nitrogen source, after 12 days of incubation, incubation temperature 25 °C and pH = 6.5. Peroxidase purified in four purification steps; precipitation with 70% saturation of ammonium sulfate, step of dialysis, the third by ion exchange chromatography using DEAE-Cellulose and fourth by gel filtration throughout Sephadex G-100. The specific activity of the purified enzyme was 150U/mg with 7.75 folds. The peroxidase was shown to have molecular weight of 40kDa in SDS-PAGA and about 40kDa in gel filtration.The optimum pH and temperature for peroxidase activity 7 and 35 C0 respectively.

  17. Strengthening of antioxidant defense by Azadirachta indica in alloxan-diabetic rat tissues

    Directory of Open Access Journals (Sweden)

    Sweta Shailey

    2012-01-01

    Full Text Available Background: Azadirachta indica has been reported to correct altered glycaemia in diabetes. Objective: The aqueous extract of A. indica leaf and bark has been evaluated for its effect on antioxidant status of alloxan diabetic rats and compared with insulin treatment. Materials and Methods: The oral effective dose of A. indica leaf (500 mg/kg body weight and A. indica bark (100 mg/kg body weight were given once daily for 21 days to separate groups of diabetic rats. At the end of the experimental period blood glucose level and activity of superoxide dismutase (SOD, catalase (CAT, glutathione peroxidase (GPx, glutathione reductase (GR, glucose-6-phosphate dehydrogenase (G-6-PD, and membrane lipid peroxidation were determined in different fractions of liver and kidney tissues. Results: Diabetic rats showed high blood glucose (P<0.01, increased level of malondialdehyde (P<0.05 and a significant decrease in the activity of antioxidant enzymes. Treatment with insulin, A. indica leaf extract (AILE, and A. indica bark extract (AIBE restored the above altered parameters close to the control ones. Conclusions: Both AILE and AIBE were found significantly effective in reducing hyperglycemia-induced oxidative stress. The findings suggest further investigations for the possible use of A. indica as alternative medicine to prevent long-term complications of diabetes.

  18. Nanotoxicity of pure silica mediated through oxidant generation rather than glutathione depletion in human lung epithelial cells.

    Science.gov (United States)

    Akhtar, Mohd Javed; Ahamed, Maqusood; Kumar, Sudhir; Siddiqui, Huma; Patil, Govil; Ashquin, Mohd; Ahmad, Iqbal

    2010-10-09

    Though, oxidative stress has been implicated in silica nanoparticles induced toxicity both in vitro and in vivo, but no similarities exist regarding dose-response relationship. This discrepancy may, partly, be due to associated impurities of trace metals that may present in varying amounts. Here, cytotoxicity and oxidative stress parameters of two sizes (10 nm and 80 nm) of pure silica nanoparticles was determined in human lung epithelial cells (A549 cells). Both sizes of silica nanoparticles induced dose-dependent cytotoxicity as measured by MTT [3-(4,5-dimethyl thiazol-2-yl)-2,5-diphenyl tetrazolium bromide] and lactate dehydrogenase (LDH) assays. Silica nanoparticles were also found to induce oxidative stress in dose-dependent manner indicated by induction of reactive oxygen species (ROS) generation, and membrane lipid peroxidation (LPO). However, both sizes of silica nanoparticles had little effect on intracellular glutathione (GSH) level and the activities of glutathione metabolizing enzymes; glutathione reductase (GR) and glutathione peroxidase (GPx). Buthionine-[S,R]-sulfoximine (BSO) plus silica nanoparticles did not result in significant GSH depletion than that caused by BSO alone nor N-acetyl cysteine (NAC) afforded significant protection from ROS and LPO induced by silica nanoparticles. The rather unaltered level of GSH is also supported by finding no appreciable alteration in the level of GR and GPx. Our data suggest that the silica nanoparticles exert toxicity in A549 cells through the oxidant generation (ROS and LPO) rather than the depletion of GSH. Copyright © 2010 Elsevier Ireland Ltd. All rights reserved.

  19. GPX4 and GPX7 Over-Expression in Human Hepatocellular Carcinoma Tissues

    Science.gov (United States)

    Guerriero, E.; Capone, F.; Accardo, M.; Sorice, A.; Costantini, M.; Colonna, G.; Castello, G.

    2015-01-01

    Hepatocellular carcinoma (HCC) is the most common type of liver cancer and is still one of the most fatal cancers. Hence, it needs to identify always new putative markers to improve its diagnosis and prognosis. The selenium is an essential trace mineral implicated as a key factor in the early stage of cancer and exerts its biological function through the selenoproteins. In the last years our group has been studying the involvement of some selenoproteins in HCC. However, no many data are reported in literature about the correlation between HCC and the glutathione peroxidases (GPXs), both selenium and non selenium-containing GPXs. In this paper we have evaluated the GPX4 and GPX7 expression in some paraffin-embedded tissues from liver biopsy of patients with hepatitis C virus (HCV)-related cirrhosis and HCC by immunohistochemistry and RT-qPCR analysis. Our results evidenced that i) GPX4 and GPX7 had a statistically significant over-expression in HCC tissues compared to cirrhotic counterparts used as non tumor tissues, and ii) their expression was higher in grade III HCC tissues with respect to grade I-II samples. Therefore, we propose to use GPX4 and GPX7 as possible markers for improving HCC diagnosis/prognosis. PMID:26708178

  20. Tetra(p-tolyl)borate-functionalized solvent polymeric membrane: a facile and sensitive sensing platform for peroxidase and peroxidase mimetics.

    Science.gov (United States)

    Wang, Xuewei; Qin, Wei

    2013-07-22

    The determination of peroxidase activities is the basis for enzyme-labeled bioaffinity assays, peroxidase-mimicking DNAzymes- and nanoparticles-based assays, and characterization of the catalytic functions of peroxidase mimetics. Here, a facile, sensitive, and cost-effective solvent polymeric membrane-based peroxidase detection platform is described that utilizes reaction intermediates with different pKa values from those of substrates and final products. Several key but long-debated intermediates in the peroxidative oxidation of o-phenylenediamine (o-PD) have been identified and their charge states have been estimated. By using a solvent polymeric membrane functionalized by an appropriate substituted tetraphenylborate as a receptor, those cationic intermediates could be transferred into the membrane from the aqueous phase to induce a large cationic potential response. Thus, the potentiometric indication of the o-PD oxidation catalyzed by peroxidase or its mimetics can be fulfilled. Horseradish peroxidase has been detected with a detection limit at least two orders of magnitude lower than those obtained by spectrophotometric techniques and traditional membrane-based methods. As an example of peroxidase mimetics, G-quadruplex DNAzymes were probed by the intermediate-sensitive membrane and a label-free thrombin detection protocol was developed based on the catalytic activity of the thrombin-binding G-quadruplex aptamer. Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  1. Understanding the degradation of ascorbic acid and glutathione in relation to the levels of oxidative stress biomarkers in broccoli (Brassica oleracea L. italica cv. Bellstar) during storage and mechanical processing.

    Science.gov (United States)

    Raseetha, Siva; Leong, Sze Ying; Burritt, David John; Oey, Indrawati

    2013-06-01

    The purpose of this research was to understand the degradation of ascorbic acid and glutathione content in broccoli florets (Brassica oleracea L. italica cv. Bellstar) during prolonged storage and subsequent mechanical processing. The initial content of total ascorbic acid and glutathione in broccoli florets averaged at 5.18 ± 0.23 and 0.70 ± 0.03 μmol/g fresh weight, respectively. Results showed that the content of ascorbic acid and glutathione in broccoli degraded during storage at 23°C, for at least 4.5-fold after 6 days of storage. On each day of storage, broccoli florets were mechanically processed, but the content of total ascorbic acid and glutathione was not significantly affected. When the mechanically processed broccoli florets were further incubated for up to 6h, the amount of ascorbic acid was greatly reduced as compared to glutathione. To obtain an in-depth understanding on the degradation of ascorbic acid and glutathione, the activity of enzymes involved in plant antioxidative system via ascorbate-glutathione cycle, as a response towards oxidative stress that took place during storage was determined in this study. The content of total ascorbic acid and glutathione in broccoli florets before and after mechanical processing were found to decrease concurrently with the activity of ascorbic acid peroxidase and glutathione reductase over the experimental storage duration. Meanwhile, the effect of oxidative stress on the content of ascorbic acid and glutathione was apparent during the 6h of incubation after mechanical processing. This phenomenon was demonstrated by the level of oxidative stress biomarkers examined, in which the formation of lipid peroxides, protein carbonyls and DNA oxidised products was positively associated with the degradation of total ascorbic acid and glutathione. Copyright © 2012 Elsevier Ltd. All rights reserved.

  2. Photosynthetic pigments and peroxidase activity of Lepidium sativum L. during assisted Hg phytoextraction.

    Science.gov (United States)

    Smolinska, Beata; Leszczynska, Joanna

    2017-05-01

    The study was conducted to evaluate metabolic answer of Lepidium sativum L. on Hg, compost, and citric acid during assisted phytoextraction. The chlorophyll a and b contents, total carotenoids, and activity of peroxidase were determined in plants exposed to Hg and soil amendments. Hg accumulation in plant shoots was also investigated. The pot experiments were provided in soil artificially contaminated by Hg and/or supplemented with compost and citric acid. Hg concentration in plant shoots and soil substrates was determined by cold vapor atomic absorption spectroscopy (CV-AAS) method after acid mineralization. The plant photosynthetic pigments and peroxidase activity were measured by standard spectrophotometric methods. The study shows that L. sativum L. accumulated Hg in its aerial tissues. An increase in Hg accumulation was noticed when soil was supplemented with compost and citric acid. Increasing Hg concentration in plant shoots was correlated with enhanced activation of peroxidase activity and changes in total carotenoid concentration. Combined use of compost and citric acid also decreased the chlorophyll a and b contents in plant leaves. Presented study reveals that L. sativum L. is capable of tolerating Hg and its use during phytoextraction assisted by combined use of compost and citric acid lead to decreasing soil contamination by Hg.

  3. Effects of ageing on peroxidase activity and localization in radish (Raphanus sativus L. seeds

    Directory of Open Access Journals (Sweden)

    A. Scialabba

    2010-05-01

    Full Text Available Peroxidase activity was assayed in crude extracts of integument, cotyledons and embryo axis of radish seeds, deteriorated under accelerated ageing conditions. Over five days of ageing, in which germination decreased from 100 to 52%, the enzyme activity in integument was higher than that in other seed parts, increasing in the first days of ageing and then decreasing sharply in extremely aged seeds. Polyacrylamide gel electrophoresis analysis showed four peroxidase isoenzymes with MM of 98, 52.5, 32.8 and 29.5 kDa in the embryo axis of unaged seeds, and only the 32.8 and 29.5 kDa MM isoforms in the integument and cotyledons. In these parts of the seed, only the 29.5 kDa MM isoenzyme increased in activity in early days of ageing and decreased thereafter. In the embryo axis, the 29.5 kDa MM isoenzyme activity increased slowly in the first day of ageing, while the 98 and 52.5 kDa MM isoenzyme activities disappeared. A cytochemical localization of peroxidase activity in the various tissues showed that main differences between unaged and extremely aged seeds occurred in the embryo axis.

  4. Effect of asoka on the intracellular glutathione levels and skin tumour promotion in mice.

    Science.gov (United States)

    Varghese, C D; Nair, S C; Panikkar, B; Panikkar, K R

    1993-04-15

    The bark of Saraka asoca (asoka) is commonly used to treat various diseases by the Indian system of medicine and in Sri Lanka. Further purification and chemical analysis of the active compound from the bark extract of asoka showed that (-)-epicatechin was responsible for the observed antitumour/anticarcinogenic activity. Papilloma formation in mice initiated with 7,12-dimethylbenz[a]anthracene (DMBA) and promoted using croton oil was inhibited by the topical application of 100 mg/kg body weight (b.w.) of (-)-epicatechin isolated from asoka bark extract. Oral administration of the same dose restricted the growth of s.c. injected 20 methylcholanthrene (MCA) induced soil tissue fibrosarcomas significantly in mice. Elevations of almost 2-4-fold in the intracellular reduced glutathione and related enzymes viz., glutathione reductase and glutathione S-transferase of sarcoma-180 tumour cells were noted in the presence of 1 microgram/ml of (-)-epicatechin, further highlighting its antiproliferative effect.

  5. Petunia peroxidase a: isolation, purification and characteristics.

    Science.gov (United States)

    Hendriks, T; Wijsman, H J; van Loon, L C

    1991-07-01

    The fast-moving anionic peroxidase isoenzyme variant PRXa was purified from leaves of petunia (Petunia hybrida). Over 1300-fold purification was achieved by subjecting extracellular extracts to two sequential acetone precipitations and resuspending the pellets at pH 5.0 and pH 8.0, respectively, followed by gel filtration and chromatofocusing. The purified enzyme had an absorbance ratio (A405 nm/A280 nm) of 3.6, a molecular mass of about 37 kDa and a pI of 3.8. Three molecular forms with slightly different molecular masses were separated by concanavalin-A--Sepharose affinity chromatography, indicating that these three forms differ in their carbohydrate moieties. The absorption spectrum of PRXa had maxima at 496 and 636 nm and a Soret band at 405 nm. Spectra of compounds I and IV were obtained by titrating a batch of PRXa stored for several months at -20 degrees C with H2O2. The addition of 1 mol H2O2/mol freshly purified PRXa caused the formation of compound II, indicating that freshly isolated PRXa contains a bound hydrogen donor which is lost upon storage. Compound III was obtained from both preparations in the presence of excess H2O2. The pH optimum of PRXa for the reaction with H2O2 and guaiacol was 5.0 and its specific activity 61 mkat/g protein. Among various aromatic compounds, coniferyl alcohol was polymerized by PRXa to presumed lignin-like material. The extracellular localization and high affinity of PRXa for the cinnamic acid derivatives suggest that this isoenzyme functions in the polymerization or cross-linking of lignin in the plant cell wall.

  6. Apple and quince peroxidase activity in response to essential oils ...

    African Journals Online (AJOL)

    Jane

    2011-09-28

    Sep 28, 2011 ... activities of edible coatings enriched with natural plant extracts such as rosemary ..... its oxidation by ascorbate peroxidase activity (Talano et al., 2008). ... delicious and quince improved the antioxidant protection of the fruits ...

  7. Evaluation of Crude Oil Biodegradation Efficiency and Peroxidase ...

    African Journals Online (AJOL)

    ADOWIE PERE

    Increase in biomass enhanced degradation efficiency above 80 % after 10 days for all concentration of crude oil studied. Peroxidase ... compounds by various bacteria and fungi (Gianfreda et al, 1999) ... into a clean plastic container. Microbial.

  8. Studies of peroxidase isozyme profile in mungbean mutants

    International Nuclear Information System (INIS)

    Auti, S.G.; Apparao, B.J.

    2007-01-01

    Peroxidase is an important oxygen-scavenging enzyme. The activity of peroxidase is often correlated with growth, development and hormonal activity. Traditional methods of cultivar identification usually involve observation and recording of morphological characters or description such as yield, height, weight, earliness etc. which vary with environmental conditions and often misleading. So molecular markers like protein and isozymes profiles, RFLP, RAPDs markers etc. are widely employed in varietal identification of cultivars. It plays important role in respiration and is an indicator of oxidative status of plants. Electrophoretic techniques have been used to group species and identify cultivars. Such identification has various advantages including the unique pattern of protein or isozymes bands for each pure cultivar under any set of environmental conditions. Peroxidase isozyme serves as very good marker for any mutational studies. In the present investigation, peroxidase isozyme profiles of various mutants of mungbean was studied employing the technique of electrophoresis

  9. Effect of heat treatment on polyphenol oxidase and peroxidase ...

    African Journals Online (AJOL)

    GREGO

    2006-12-18

    Dec 18, 2006 ... enzymes in plant and its resistance to heat has been reported by a ... sintered glass funnel and washed with cold acetone under low vacuum ... Peroxidase activity was determined by measuring the colour deve- lopment at ...

  10. Production of manganese peroxidase by white rot fungi from potato ...

    African Journals Online (AJOL)

    PRECIOUS

    2010-01-18

    Jan 18, 2010 ... production rate of the MnP using the potato-processing wastewater-based medium were higher (ca. 2.5- ... Ligninolytic enzymes, such as manganese peroxidase ... not currently reached industrial levels except for the laccase.

  11. Cell wall bound anionic peroxidases from asparagus byproducts.

    Science.gov (United States)

    Jaramillo-Carmona, Sara; López, Sergio; Vazquez-Castilla, Sara; Jimenez-Araujo, Ana; Rodriguez-Arcos, Rocio; Guillen-Bejarano, Rafael

    2014-10-08

    Asparagus byproducts are a good source of cationic soluble peroxidases (CAP) useful for the bioremediation of phenol-contaminated wastewaters. In this study, cell wall bound peroxidases (POD) from the same byproducts have been purified and characterized. The covalent forms of POD represent >90% of the total cell wall bound POD. Isoelectric focusing showed that whereas the covalent fraction is constituted primarily by anionic isoenzymes, the ionic fraction is a mixture of anionic, neutral, and cationic isoenzymes. Covalently bound peroxidases were purified by means of ion exchange chromatography and affinity chromatography. In vitro detoxification studies showed that although CAP are more effective for the removal of 4-CP and 2,4-DCP, anionic asparagus peroxidase (AAP) is a better option for the removal of hydroxytyrosol (HT), the main phenol present in olive mill wastewaters.

  12. Platelet crossmatch tests using radiolabelled staphylococcal protein A or peroxidase anti-peroxidase in alloimmunised patients

    International Nuclear Information System (INIS)

    Yam, P.; Petz, L.D.; Scott, E.P.; Santos, S.

    1984-01-01

    Refractoriness to random-donor platelets as a result of alloimmunization remains a major problem in long-term platelet transfusion therapy despite the use of HLA-matched platelets. A study has been made of two methods for detection of platelet associated IgG as platelet crossmatch tests for the selection of platelet donors. These methods use radiolabelled staphylococcal protein A( 125 I-SPA) and peroxidase anti-peroxidase (PAP), respectively. One hundred and ten crossmatch tests using 125 I-SPA were performed retrospectively in 18 alloimmunized patients. The results indicated that the predictive value of a positive or a negative test was 87%; the sensitivity was 73% and the specificity was 95%. Results with the PAP test were similar. The HLA types were known for 48 donor-recipient pairs. With few exceptions, there was a correlation between the results of the platelet crossmatch tests and the effectiveness of platelet transfusion regardless of the degree of HLA match. These results indicate that platelet crossmatch tests may be valuable even when closely HLA matched donors are not available. A large-scale prospective study is warranted, particularly in highly immunized patients. (author)

  13. A glutathione s-transferase confers herbicide tolerance in rice

    Directory of Open Access Journals (Sweden)

    Tingzhang Hu

    2014-07-01

    Full Text Available Plant glutathione S-transferases (GSTs have been a focus of attention due to their role in herbicide detoxification. OsGSTL2 is a glutathione S-transferase, lambda class gene from rice (Oryza sativa L.. Transgenic rice plants over-expressing OsGSTL2 were generated from rice calli by the use of an Agrobacterium transformation system, and were screened by a combination of hygromycin resistance, PCR and Southern blot analysis. In the vegetative tissues of transgenic rice plants, the over-expression of OsGSTL2 not only increased levels of OsGSTL2 transcripts, but also GST and GPX expression, while reduced superoxide. Transgenic rice plants also showed higher tolerance to glyphosate and chlorsulfuron, which often contaminate agricultural fields. The findings demonstrate the detoxification role of OsGSTL2 in the growth and development of rice plants. It should be possible to apply the present results to crops for developing herbicide tolerance and for limiting herbicide contamination in the food chain.

  14. Glutathione--linking cell proliferation to oxidative stress.

    Science.gov (United States)

    Diaz-Vivancos, Pedro; de Simone, Ambra; Kiddle, Guy; Foyer, Christine H

    2015-12-01

    The multifaceted functions of reduced glutathione (gamma-glutamyl-cysteinyl-glycine; GSH) continue to fascinate plants and animal scientists, not least because of the dynamic relationships between GSH and reactive oxygen species (ROS) that underpin reduction/oxidation (redox) regulation and signalling. Here we consider the respective roles of ROS and GSH in the regulation of plant growth, with a particular focus on regulation of the plant cell cycle. Glutathione is discussed not only as a crucial low molecular weight redox buffer that shields nuclear processes against oxidative challenge but also a flexible regulator of genetic and epigenetic functions. The intracellular compartmentalization of GSH during the cell cycle is remarkably consistent in plants and animals. Moreover, measurements of in vivo glutathione redox potentials reveal that the cellular environment is much more reducing than predicted from GSH/GSSG ratios measured in tissue extracts. The redox potential of the cytosol and nuclei of non-dividing plant cells is about -300 mV. This relatively low redox potential maintained even in cells experiencing oxidative stress by a number of mechanisms including vacuolar sequestration of GSSG. We propose that regulated ROS production linked to glutathione-mediated signalling events are the hallmark of viable cells within a changing and challenging environment. The concept that the cell cycle in animals is subject to redox controls is well established but little is known about how ROS and GSH regulate this process in plants. However, it is increasingly likely that redox controls exist in plants, although possibly through different pathways. Moreover, redox-regulated proteins that function in cell cycle checkpoints remain to be identified in plants. While GSH-responsive genes have now been identified, the mechanisms that mediate and regulate protein glutathionylation in plants remain poorly defined. The nuclear GSH pool provides an appropriate redox environment

  15. Antioxidant response and metal accumulation in tissues of Iberian green frogs (Pelophylax perezi) inhabiting a deactivated uranium mine.

    Science.gov (United States)

    Marques, Sérgio M; Antunes, Sara C; Nunes, Bruno; Gonçalves, Fernando; Pereira, Ruth

    2011-08-01

    Human mining activities tend often to generate greatly impacted areas which remain contaminated for long periods of time, giving rise to extreme habitats. Mining sites are usually characterized for the production of metal rich effluents with very low pH. In this work we analyzed physical and chemical parameters of water from a deactivated uranium mine pond (M) and a reference site (REF) as well as their metal content. Furthermore, we determined and compared metal accumulation in liver, kidney, bones, muscle and skin of Pelophylax perezi from REF with P. perezi from M. We also determined the enzymatic activities of glutathione-S-transferases (GSTs), catalase (CAT), glutathione reductase (Gred), and glutathione peroxidase (GPx; both selenium-dependent and selenium-independent) in liver, kidney, lung and heart. Additionally, lipoperoxidation (LPO) was also assessed in the same tissues via thiobarbituric acid reactive substances (TBARS) assay and lactate dehydrogenase (LDH) activity was determined in muscle. Our results revealed that the majority of metals were in higher concentrations in tissues of organisms from M. This trend was especially evident for U whose content reached a difference of 1350 fold between REF and M organisms. None of the organs tested for antioxidant defenses revealed LPO, nonetheless, with exception for liver, all organs from the M frogs presented increased total GPx activity and selenium-dependent GPx. However, this response was significant only for the lung, probably as a consequence of the significant inhibition of CAT upstream and to cope with the subsequent increase in H(2)O(2). Lungs were the organs displaying greater responsiveness of the anti-oxidant stress system in frogs from the uranium mine area.

  16. Structure of soybean seed coat peroxidase: a plant peroxidase with unusual stability and haem-apoprotein interactions

    DEFF Research Database (Denmark)

    Henriksen, A; Mirza, O; Indiani, C

    2001-01-01

    Soybean seed coat peroxidase (SBP) is a peroxidase with extraordinary stability and catalytic properties. It belongs to the family of class III plant peroxidases that can oxidize a wide variety of organic and inorganic substrates using hydrogen peroxide. Because the plant enzyme is a heterogeneous...... glycoprotein, SBP was produced recombinant in Escherichia coli for the present crystallographic study. The three-dimensional structure of SBP shows a bound tris(hydroxymethyl)aminomethane molecule (TRIS). This TRIS molecule has hydrogen bonds to active site residues corresponding to the residues that interact...... with the small phenolic substrate ferulic acid in the horseradish peroxidase C (HRPC):ferulic acid complex. TRIS is positioned in what has been described as a secondary substrate-binding site in HRPC, and the structure of the SBP:TRIS complex indicates that this secondary substrate-binding site could...

  17. Peroxidase activity in root hairs of cress (lepidium sativum L.) Cytochemical localization and radioactive labelling of wall bound peroxidase

    International Nuclear Information System (INIS)

    Zaar, K.

    1979-01-01

    The ultrastructural localization of peroxidase activity in young, growing root hairs of cress (Lepidium sativum L.) after assay with 3,3'-diaminobenzidine is reported. Prominent peroxidase activity has been found in the dictyosomes and the associated vesicles, in ribosomes on ER-cisternae, as well as in the cell wall. On the basis of both ultrastructural and cytochemical evidence it is proposed that peroxidase in root hairs is synthesized on the ER- and within dictyosome cisternae packaged and transported in secretory vesicles and extruded into the cell wall particularily at the tip region of a root hair. The kinetic of Golgi apparatus mediated peroxidasesecretion was monitored by measuring the 55 Fe protoheme content of primary cell walls. Peroxidase secretion seems to be enhanced during stress incubation in destilled water. Secretory activity in root hairs is 20 times higher than in cells of the root body. (author)

  18. Potential of Glutathione Antioxidant in the Hippocampus Repair: Preliminary Study on Bioactive Materials Antiaging of Snakehead Fish (Channa striata in Animal Models of Aging

    Directory of Open Access Journals (Sweden)

    Sunarno Sunarno

    2014-12-01

    Full Text Available Snakehead fish meat contains active ingredients with anti-aging potential that serves as a precursor of glutathione. The ability of glutathione as an antiaging opportunities in the utilization of fish meat, especially snakehead fish. Snakehead fish meat contains several important amino acids, such as glutamine, cysteine​​, and glycine so the potential to be developed for the production of food that is nutritious and healthy. This study examines the essential amino acid composition of the antioxidant glutathione precursors found in snakehead fish from Rawa Pening Central Java to increase glutathione in the body and brain. The results showed that every 100g of snakehead fish meat from Rawa Pening containing glutamine (32.39%, cysteine ​​(6.61%, and glycine (9.69%. Snakehead fish meat extract given at a dose of 30 ml/kg/day in both types of animal models of aging effect on the increase in the content of glutathione and glutathione precursors, both in blood and hippocampus. Increased glutathione precursor of the most high to low, respectively glutamine, glycine, and cysteine​​. Availability of essential amino acids can support increased glutathione in the brain. This is indicated by an increase in glutathione hippocampus in both animal models, both on chronological aging or aging due to oxidative stress, respectively (0.822 and 0.359 mol/g bb compared to control tissue.

  19. Optimization of lignin peroxidase, manganese peroxidase, and Lac production from Ganoderma lucidum under solid state fermentation of pineapple leaf

    OpenAIRE

    Sudha Hariharan; Padma Nambisan

    2013-01-01

    This study was undertaken to isolate ligninase-producing white-rot fungi for use in the extraction of fibre from pineapple leaf agriwaste. Fifteen fungal strains were isolated from dead tree trunks and leaf litter. Ligninolytic enzymes (lignin peroxidase (LiP), manganese peroxidase (MnP), and laccase (Lac)), were produced by solid-state fermentation (SSF) using pineapple leaves as the substrate. Of the isolated strains, the one showing maximum production of ligninolytic enzymes was identified...

  20. The effects of propolis extract on ovarian tissue and oxidative stress in rats with maternal separation stress

    Directory of Open Access Journals (Sweden)

    Atefeh Arabameri

    2017-09-01

    Full Text Available Abstract Background: Stress in infancy has dramatic effects on different systems, including the nervous system, endocrine, immune, reproductive and etc. Objective: The purpose of this study was to investigate the effects of extract of Iranian propolis (EIP on ovarian tissue and oxidative stress in rats with maternal separation stress. Materials and Methods: 48 immature female rats were divided randomly into six groups. 1 Control group, 2 Control group+saline, 3 Stress group, includes infants that were separated from their mothers 6 hr/day, the 4th, 5th and 6th groups consisted of infants who in addition to daily stress received 50, 100 and 200 mg/kg of EIP, respectively. Then serum corticosterone, 17-beta-estradiol, malondialdehyde, total superoxide dismutase, glutathione peroxidase and ferric reducing antioxidant power levels were measured. The ovarian sections were stained by H&E, PAS, and TUNEL methods and were studied with optical microscopy. Results: Stress increased the blood serum corticosterone levels and 17-beta-estradiol reduced significantly (p<0.001 and EIP prevented from this changes (p<0.01. EIP significantly increased the number of ovarian follicles, oocytes and oocytes diameter in neonatal rat following stress (p<0.01. EIP also significantly decreased the number of atretic follicles, TUNEL+granulosa cells, malondialdehyde levels and increased ferric reducing antioxidant power, total superoxide dismutase and glutathione peroxidase serum levels in neonatal rats following stress. The dose of 200 mg/kg EIP was more effective. Conclusion: This Study showed that the Iranian Propolis significantly could prevent oxidative stress and histopathological changes in the ovary of the neonatal rat the following stress.

  1. Comparative study on the peroxidase activity from the floats of Caulerpa lentillifera (grapes seaweeds), roots of Tamarindus indica (tamarind), Eichhornia crassipes (water hyacinth) and Dracaena surculosa (spotted dracaena)

    International Nuclear Information System (INIS)

    Berosil, Maan Dyann N.; Magtibay, Cherrie Joy C.

    2005-02-01

    Peroxidase activities from four different varieties of plant roots were investigated through the use of UV-Vis spectrophotometer. Hydrogen peroxide was used as the substrate and phosphate buffer at a pH that have been determined to be the optimal pH for peroxidase activity for the specific sample type. The four plant root extracts showed an assay pH optimum of 7.5 for the Tamarindus indica (tamarind) and Eichhornia crassipes (water hyacinth), pH 5.5 for Dracaena surculosa (spotted dracaena) and pH 7.0 for Caulerpa lentillifera (grapes seaweeds) using Maehly and Chance method. Determination of peroxidase at 510 nm of the four extracts indicated that, spotted dracaena gave the highest peroxidase activity with 361.07 U ml -1 , followed by tamarind with 57.11 U ml -1 , then water hyacinth with 29.39 U m -1 and lastly, grapes seaweeds with 7.55 U ml -1 . The specific peroxidase activities of the spotted dracaena, water hyacinth, tamarind and grapes seaweeds are 0.3224, 0.2048, 0.0721 and 0.0341 U mg -1 respectively. The peroxidase of the four plant tissues that were kept at ultra low personal freezer for almost a week was degraded. (Authors)

  2. The effect of aspirin nanoemulsion on TNFα and iNOS in gastric tissue in comparison with conventional aspirin

    Directory of Open Access Journals (Sweden)

    Mahmoud FA

    2015-08-01

    increase in TNFα, iNOS, prostaglandin E2, and malondialdehyde levels, and also a significant decrease in glutathione, glutathione reductase, glutathione peroxidase, catalase, and superoxide dismutase. In the aspirin-treated group compared to the control group, the NE had a protective effect on the stomach and caused less injury than aspirin, indicated by significant decreases in TNFα, iNOS, prostaglandin E2, and malondialdehyde levels, and also significant increases in glutathione, glutathione reductase, glutathione peroxidase, catalase, and superoxide dismutase. The biochemical results were confirmed by histopathological studies.Conclusion: Aspirin nanoemulsion has less toxic effect on the gastric mucosa compared to ordinary aspirin. This can be indicated by the increase of the antioxidant activity and the decrease of the inflammatory mediators in the gastric tissue.Keywords: aspirin, aspirin nanoemulsion, blank nanoemulsion, stomach

  3. Beta-carotene reduces oxidative stress, improves glutathione metabolism and modifies antioxidant defense systems in lead-exposed workers

    International Nuclear Information System (INIS)

    Kasperczyk, Sławomir; Dobrakowski, Michał; Kasperczyk, Janusz; Ostałowska, Alina; Zalejska-Fiolka, Jolanta; Birkner, Ewa

    2014-01-01

    The aim of this study was to determine whether beta-carotene administration reduces oxidative stress and influences antioxidant, mainly glutathione-related, defense systems in workers chronically exposed to lead. The population consisted of two randomly divided groups of healthy male volunteers exposed to lead. Workers in the first group (reference group) were not administered any antioxidants, while workers in the second group (CAR group) were treated orally with 10 mg of beta-carotene once a day for 12 weeks. Biochemical analysis included measuring markers of lead-exposure and oxidative stress in addition to the levels and activities of selected antioxidants. After treatment, levels of malondialdehyde, lipid hydroperoxides and lipofuscin significantly decreased compared with the reference group. However, the level of glutathione significantly increased compared with the baseline. Treatment with beta-carotene also resulted in significantly decreased glutathione peroxidase activity compared with the reference group, while the activities of other glutathione-related enzymes and of superoxide dismutase were not significantly changed. However, the activities of glucose-6-phosphate dehydrogenase and catalase, as well as the level of alpha-tocopherol, were significantly higher after treatment compared with the baseline. Despite controversy over the antioxidant properties of beta-carotene in vivo, our findings showed reduced oxidative stress after beta-carotene supplementation in chronic lead poisoning. - Highlights: • Beta-carotene reduces oxidative stress in lead-exposed workers. • Beta-carotene elevates glutathione level in lead-exposed workers. • Beta-carotene administration could be beneficial in lead poisoning

  4. Beta-carotene reduces oxidative stress, improves glutathione metabolism and modifies antioxidant defense systems in lead-exposed workers

    Energy Technology Data Exchange (ETDEWEB)

    Kasperczyk, Sławomir, E-mail: kaslav@mp.pl [Dept. of Biochemistry, School of Medicine with the Division of Dentistry, Medical University of Silesia, ul. Jordana 19, 41-808 Zabrze (Poland); Dobrakowski, Michał [Dept. of Biochemistry, School of Medicine with the Division of Dentistry, Medical University of Silesia, ul. Jordana 19, 41-808 Zabrze (Poland); Kasperczyk, Janusz [Dept. of Environmental Medicine and Epidemiology, School of Medicine with the Division of Dentistry, Medical University of Silesia, ul. Jordana 19, 41-808 Zabrze (Poland); Ostałowska, Alina; Zalejska-Fiolka, Jolanta; Birkner, Ewa [Dept. of Biochemistry, School of Medicine with the Division of Dentistry, Medical University of Silesia, ul. Jordana 19, 41-808 Zabrze (Poland)

    2014-10-01

    The aim of this study was to determine whether beta-carotene administration reduces oxidative stress and influences antioxidant, mainly glutathione-related, defense systems in workers chronically exposed to lead. The population consisted of two randomly divided groups of healthy male volunteers exposed to lead. Workers in the first group (reference group) were not administered any antioxidants, while workers in the second group (CAR group) were treated orally with 10 mg of beta-carotene once a day for 12 weeks. Biochemical analysis included measuring markers of lead-exposure and oxidative stress in addition to the levels and activities of selected antioxidants. After treatment, levels of malondialdehyde, lipid hydroperoxides and lipofuscin significantly decreased compared with the reference group. However, the level of glutathione significantly increased compared with the baseline. Treatment with beta-carotene also resulted in significantly decreased glutathione peroxidase activity compared with the reference group, while the activities of other glutathione-related enzymes and of superoxide dismutase were not significantly changed. However, the activities of glucose-6-phosphate dehydrogenase and catalase, as well as the level of alpha-tocopherol, were significantly higher after treatment compared with the baseline. Despite controversy over the antioxidant properties of beta-carotene in vivo, our findings showed reduced oxidative stress after beta-carotene supplementation in chronic lead poisoning. - Highlights: • Beta-carotene reduces oxidative stress in lead-exposed workers. • Beta-carotene elevates glutathione level in lead-exposed workers. • Beta-carotene administration could be beneficial in lead poisoning.

  5. Toll-Like Receptor 4 Reduces Oxidative Injury via Glutathione Activity in Sheep

    Directory of Open Access Journals (Sweden)

    Shoulong Deng

    2016-01-01

    Full Text Available Toll-like receptor 4 (TLR4 is an important sensor of Gram-negative bacteria and can trigger activation of the innate immune system. Increased activation of TLR4 can lead to the induction of oxidative stress. Herein, the pathway whereby TLR4 affects antioxidant activity was studied. In TLR4-overexpressing sheep, TLR4 expression was found to be related to the integration copy number when monocytes were challenged with lipopolysaccharide (LPS. Consequently, production of malondialdehyde (MDA was increased, which could increase the activation of prooxidative stress enzymes. Meanwhile, activation of an antioxidative enzyme, glutathione peroxidase (GSH-Px, was increased. Real-time PCR showed that expression of activating protein-1 (AP-1 and the antioxidative-related genes was increased. By contrast, the expression levels of superoxide dismutase 1 (SOD1 and catalase (CAT were reduced. In transgenic sheep, glutathione (GSH levels were dramatically reduced. Furthermore, transgenic sheep were intradermally injected with LPS in each ear. The amounts of inflammatory infiltrates were correlated with the number of TLR4 copies that were integrated in the genome. Additionally, the translation of γ-glutamylcysteine synthetase (γ-GCS was increased. Our findings indicated that overexpression of TLR4 in sheep could ameliorate oxidative injury through GSH secretion that was induced by LPS stimulation. Furthermore, TLR4 promoted γ-GCS translation through the AP-1 pathway, which was essential for GSH synthesis.

  6. Correction of glutathione deficiency in the lower respiratory tract of HIV seropositive individuals by glutathione aerosol treatment.

    Science.gov (United States)

    Holroyd, K J; Buhl, R; Borok, Z; Roum, J H; Bokser, A D; Grimes, G J; Czerski, D; Cantin, A M; Crystal, R G

    1993-10-01

    Concentrations of glutathione, a ubiquitous tripeptide with immune enhancing and antioxidant properties, are decreased in the blood and lung epithelial lining fluid of human immunodeficiency virus (HIV) seropositive individuals. Since the lung is the most common site of infection in those who progress to AIDS it is rational to consider whether it is possible to safely augment glutathione levels in the epithelial lining fluid of HIV seropositive individuals, thus potentially improving local host defence. Purified reduced glutathione was delivered by aerosol to HIV seropositive individuals (n = 14) and the glutathione levels in lung epithelial lining fluid were compared before and at one, two, and three hours after aerosol administration. Before treatment total glutathione concentrations in the epithelial lining fluid were approximately 60% of controls. After three days of twice daily doses each of 600 mg reduced glutathione, total glutathione levels in the epithelial lining fluid increased and remained in the normal range for at least three hours after treatment. Strikingly, even though > 95% of the glutathione in the aerosol was in its reduced form, the percentage of oxidised glutathione in epithelial lining fluid increased from 5% before treatment to about 40% three hours after treatment, probably reflecting the use of glutathione as an antioxidant in vivo. No adverse effects were observed. It is feasible and safe to use aerosolised reduced glutathione to augment the deficient glutathione levels of the lower respiratory tract of HIV seropositive individuals. It is rational to evaluate further the efficacy of this tripeptide in improving host defence in HIV seropositive individuals.

  7. Glutathione and its antiaging and antimelanogenic effects

    Directory of Open Access Journals (Sweden)

    Weschawalit S

    2017-04-01

    Full Text Available Sinee Weschawalit,1 Siriwan Thongthip,2 Phanupong Phutrakool,3 Pravit Asawanonda1 1Department of Medicine, Division of Dermatology, 2Chula Clinical Research Center, 3Chula Data Management Center, Faculty of Medicine, Chulalongkorn University, Bangkok, Thailand Background: Previous studies showed that supplementation of reduced form of glutathione (GSH, 500 mg/d has a skin-lightening efficacy in humans. This study was designed to evaluate the influences of both GSH and oxidized form (GSSG, at doses lower than 500 mg/d, on improving skin properties. Patients and methods: A randomized, double-blind, placebo-controlled, parallel, three-arm study was conducted. Healthy female subjects were equally randomized into three groups and took GSH (250 mg/d, GSSG (250 mg/d, or placebo orally for 12 weeks. At each visit at baseline and for 12 weeks, skin features including melanin index, wrinkles, and other relevant biophysical properties were measured. Blood samples were collected for safety monitoring. Results: In generalized estimating equation analyses, melanin index and ultraviolet spots of all sites including face and arm when given GSH and GSSG tended to be lower than placebo. At some sites evaluated, subjects who received GSH showed a significant reduction in wrinkles compared with those taking placebo. A tendency toward increased skin elasticity was observed in GSH and GSSG compared with placebo. There were no serious adverse effects throughout the study. Conclusion: We showed that oral glutathione, 250 mg/d, in both reduced and oxidized forms effectively influences skin properties. Overall, glutathione in both forms are well tolerated. Keywords: glutathione, melanin, pigment, aging, wrinkle, whitening

  8. Cellular glutathione prevents cytolethality of monomethylarsonic acid

    International Nuclear Information System (INIS)

    Sakurai, Teruaki; Kojima, Chikara; Ochiai, Masayuki; Ohta, Takami; Sakurai, Masumi H.; Waalkes, Michael P.; Fujiwara, Kitao

    2004-01-01

    Inorganic arsenicals are clearly toxicants and carcinogens in humans. In mammals, including humans, inorganic arsenic often undergoes methylation, forming compounds such as monomethylarsonic acid (MMAs V ) and dimethylarsinic acid (DMAs V ). However, much less information is available on the in vitro toxic potential or mechanisms of these methylated arsenicals, especially MMAs V . We studied the molecular mechanisms of in vitro cytolethality of MMAs V using a rat liver epithelial cell line (TRL 1215). MMAs V was not cytotoxic in TRL 1215 cells even at concentrations exceeding 10 mM, but it became weakly cytotoxic and induced both necrotic and apoptotic cell death when cellular reduced glutathione (GSH) was depleted with the glutathione synthase inhibitor, L-buthionine-[S,R]-sulfoximine (BSO), or the glutathione reductase inhibitor, carmustine. Similar results were observed in the other mammalian cells, such as human skin TIG-112 cells, chimpanzee skin CRT-1609 cells, and mouse metallothionein (MT) positive and MT negative embryonic cells. Ethacrynic acid (EA), an inhibitor of glutathione S-transferase (GST) that catalyses GSH-substrate conjugation, also enhanced the cytolethality of MMAs V , but aminooxyacetic acid (AOAA), an inhibitor of β-lyase that catalyses the final breakdown of GSH-substrate conjugates, had no effect. Both the cellular GSH levels and the cellular GST activity were increased by the exposure to MMAs V in TRL 1215 cells. On the other hand, the addition of exogenous extracellular GSH enhanced the cytolethality of MMAs V , although cellular GSH levels actually prevented the cytolethality of combined MMAs V and exogenous GSH. These findings indicate that human arsenic metabolite MMAs V is not a highly toxic compound in mammalian cells, and the level of cellular GSH is critical to its eventual toxic effects

  9. Early H2O2 Accumulation in Mesophyll Cells Leads to Induction of Glutathione during the Hyper-Sensitive Response in the Barley-Powdery Mildew Interaction1

    Science.gov (United States)

    Vanacker, Helene; Carver, Tim L.W.; Foyer, Christine H.

    2000-01-01

    H2O2 production and changes in glutathione, catalase, and peroxidase were followed in whole-leaf extracts from the susceptible (AlgS [Algerian/4* (F14) Man.(S)]; ml-a1 allele) and resistant (AlgR [Algerian/4* (F14) Man.(R)]; Ml-a1 allele) barley (Hordeum vulgare) isolines between 12 and 24 h after inoculation with powdery mildew (Blumeria graminis [DC]. Speer [syn. Erysiphe graminis DC] f.sp hordei Marchal). Localized papilla responses and cell death hypersensitive responses were not observed within the same cell. In hypersensitive response sites, H2O2 accumulation first occurred in the mesophyll underlying the attacked epidermal cell. Subsequently, H2O2 disappeared from the mesophyll and accumulated around attacked epidermal cells. In AlgR, transient glutathione oxidation coincided with H2O2 accumulation in the mesophyll. Subsequently, total foliar glutathione and catalase activities transiently increased in AlgR. These changes, absent from AlgS, preceded inoculation-dependent increases in peroxidase activity that were observed in both AlgR and AlgS at 18 h. An early intercellular signal precedes H2O2, and this elicits anti-oxidant responses in leaves prior to events leading to death of attacked cells. PMID:10938348

  10. A chloroplast-localized and auxin-induced glutathione S-transferase from phreatophyte Prosopis juliflora confer drought tolerance on tobacco.

    Science.gov (United States)

    George, Suja; Venkataraman, Gayatri; Parida, Ajay

    2010-03-01

    Plant growth and productivity are adversely affected by various abiotic stress factors. In our previous study, we used Prosopis juliflora, a drought-tolerant tree species of Fabaceae, as a model plant system for mining genes functioning in abiotic stress tolerance. Large-scale random EST sequencing from a cDNA library obtained from drought-stressed leaves of 2-month-old P. juliflora plants resulted in identification of three different auxin-inducible glutathione S-transferases. In this paper, we report the cellular localization and the ability to confer drought tolerance in transgenic tobacco of one of these GSTs (PjGSTU1). PjGSTU1 was overexpressed in Escherichia coli and GST and GPX activities in total protein samples were assayed and compared with controls. The results indicated that PjGSTU1 protein forms a functional homo-dimer in recombinant bacteria with glutathione transferase as well as glutathione peroxidase activities. PjGSTU1 transgenic tobacco lines survived better under conditions of 15% PEG stress compared with control un-transformed plants. In vivo localization studies for PjGSTU1 using GFP fusion revealed protein localization in chloroplasts of transgenic plants. The peroxidase activity of PjGSTU1 and its localization in the chloroplast indicates a possible role for PjGSTU1 in ROS removal. Copyright 2009 Elsevier GmbH. All rights reserved.

  11. Glutathione-mediated detoxification of halobenzoquinone drinking water disinfection byproducts in T24 cells.

    Science.gov (United States)

    Li, Jinhua; Wang, Wei; Zhang, Hongquan; Le, X Chris; Li, Xing-Fang

    2014-10-01

    Halobenzoquinones (HBQs) are a new class of drinking water disinfection byproducts (DBPs) and are capable of producing reactive oxygen species and causing oxidative damage to proteins and DNA in T24 human bladder carcinoma cells. However, the exact mechanism of the cytotoxicity of HBQs is unknown. Here, we investigated the role of glutathione (GSH) and GSH-related enzymes including glutathione S-transferase (GST) and glutathione peroxidase (GPx) in defense against HBQ-induced cytotoxicity in T24 cells. The HBQs are 2,6-dichloro-1,4-benzoquinone (DCBQ), 2,6-dichloro-3-methyl-1,4-benzoquinone (DCMBQ), 2,3,6-trichloro-1,4-benzoquinone (TriCBQ), and 2,6-dibromobenzoquinone (DBBQ). We found that depletion of cellular GSH could sensitize cells to HBQs and extracellular GSH supplementation could attenuate HBQ-induced cytotoxicity. HBQs caused significant cellular GSH depletion and increased cellular GST activities in a concentration-dependent manner. Our mass spectrometry study confirms that HBQs can conjugate with GSH, explaining in part the mechanism of GSH depletion by HBQs. The effects of HBQs on GPx activity are compound dependent; DCMBQ and DBBQ decrease cellular GPx activities, whereas DCBQ and TriCBQ have no significant effects. Pearson correlation analysis shows that the cellular GSH level is inversely correlated with ROS production and cellular GST activity in HBQ-treated cells. These results support a GSH and GSH-related enzyme-mediated detoxification mechanism of HBQs in T24 cells. © The Author 2014. Published by Oxford University Press on behalf of the Society of Toxicology. All rights reserved. For permissions, please email: journals.permissions@oup.com.

  12. Monoterpenoid indole alkaloids and phenols are required antioxidants in glutathione depleted Uncaria tomentosa root cultures

    Directory of Open Access Journals (Sweden)

    Ileana eVera-Reyes

    2015-04-01

    Full Text Available Plants cells sense their environment through oxidative signaling responses and make appropriate adjustments to gene expression, physiology and metabolic defense. Root cultures of Uncaria tomentosa, a native plant of the Amazon rainforest, were exposed to stressful conditions by combined addition of the glutathione inhibitor, buthionine sulfoximine (0.8 mM and 0.2 mM jasmonic acid. This procedure induced a synchronized two-fold increase of hydrogen peroxide and guaiacol peroxidases, while the glutathione content and glutathione reductase activity were reduced. Likewise in elicited cultures, production of the antioxidant secondary metabolites, monoterpenoid oxindole and glucoindole alkaloids, were 2.1 and 5.5-fold stimulated (704.0 ± 14.9 and 845.5 ± 13.0 µg/g DW, respectively after 12 h after, while phenols were three times increased. Upon elicitation, the activities and mRNA transcript levels of two enzymes involved in the alkaloid biosynthesis, strictosidine synthase and strictosidine β-glucosidase, were also enhanced. Differential proteome analysis performed by two-dimensional polyacrylamide gel electrophoresis of elicited and control root cultures showed that, after elicitation, several new protein spots appeared. Two of them were identified as thiol-related enzymes, namely cysteine synthase and methionine synthase. Proteins associated with antioxidant and stress responses, including two strictosidine synthase isoforms, were identified as well, together with others as caffeic acid O-methyltransferase. Our results propose that in U. tomentosa roots a signaling network involving hydrogen peroxide and jasmonate derivatives coordinately regulates the antioxidant response and secondary metabolic defense via transcriptional and protein activation.

  13. Glutathione modulation in cancer treatment: will it work

    International Nuclear Information System (INIS)

    Mitchell, J.B.; Cook, J.A.; DeGraff, W.; Glatstein, E.; Russo, A.

    1989-01-01

    Glutathione (GSH) assumes a pivotal role in numerous cellular functions including bioreductive reactions, maintenance of enzyme activity, amino acid transport, protection from harmful oxidative species, and detoxification of xenobiotics. The importance of GSH in modifying the cellular response to several anti-cancer treatment modalities has become better appreciated with the introduction of agents which can either decrease or elevate GSH levels in cells and tissues. In general, GSH depletion has been demonstrated to further enhance the cytotoxicity of several chemotherapy drugs and nitroimidazole hypoxic cell radiosensitizers. Conversely, GSH elevation affords varying degrees of protection. Whether or not GSH modulating agents will be useful as an adjuvant to selected cancer treatment modalities will depend on whether differential levels of GSH can be achieved in tumor versus normal tissues. Accurate GSH measurements in tumor and normal tissues will be required to adequately use and interpret the results of clinical studies where GSH modulating agents are employed. Precise tumor GSH measurements pose a considerable challenge due to the complicated cellular makeup of tumors.44 references

  14. Effect of an aqueous extract of Cucurbita ficifolia Bouché on the glutathione redox cycle in mice with STZ-induced diabetes.

    Science.gov (United States)

    Díaz-Flores, M; Angeles-Mejia, S; Baiza-Gutman, L A; Medina-Navarro, R; Hernández-Saavedra, D; Ortega-Camarillo, C; Roman-Ramos, R; Cruz, M; Alarcon-Aguilar, F J

    2012-10-31

    Cucurbita ficifolia is used in Mexican traditional medicine as an anti-diabetic and anti-inflammatory agent and its actions can be mediated by antioxidant mechanisms. Disturbance in the homeostasis of glutathione has been implicated in the etiology and progression of diabetes mellitus and its complications. It was evaluated, the effect of an aqueous extract of Cucurbita ficifolia on glycemia, plasma lipid peroxidation; as well as levels of reduced (GSH) and oxidized (GSSG) glutathione and activities of enzymes involved in glutathione redox cycle: glutathione peroxidase (GPx) and glutathione reductase (GR) in liver, pancreas, kidney and heart homogenates of streptozotocin-induced diabetic mice. Increased blood glucose and lipid peroxidation, together with decreased of GSH concentration, GSH/GSSG ratio and its redox potential (E(h)), and enhanced activity of GPx and GR in liver, pancreas and kidney were the salient features observed in diabetic mice. Administration of the aqueous extract of Cucurbita ficifolia to diabetic mice for 30 days, used at a dose of 200 mg/kg, resulted in a significant reduction in glycemia, polydipsia, hyperphagia and plasma lipid peroxidation. Moreover, GSH was increased in liver, pancreas and kidney, and GSSG was reduced in liver, pancreas and heart, therefore GSH/GSSG ratio and its E(h) were restored. Also, the activities involved in the glutathione cycle were decreased, reaching similar values to controls. An aqueous extract of Cucurbita ficifolia with hypoglycemic action, improve GSH redox state, increasing glutathione pool, GSH, GSH/GSSG ratio and its E(h), mechanism that can explain, at least in part, its antioxidant properties, supporting its use as an alternative treatment for the control of diabetes mellitus, and prevent the induction of complications by oxidative stress. Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.

  15. Activity-Based Probes for Isoenzyme- and Site-Specific Functional Characterization of Glutathione S -Transferases

    Energy Technology Data Exchange (ETDEWEB)

    Stoddard, Ethan G. [Chemical Biology and Exposure; Killinger, Bryan J. [Chemical Biology and Exposure; Nair, Reji N. [Chemical Biology and Exposure; Sadler, Natalie C. [Chemical Biology and Exposure; Volk, Regan F. [Chemical Biology and Exposure; Purvine, Samuel O. [Chemical Biology and Exposure; Shukla, Anil K. [Chemical Biology and Exposure; Smith, Jordan N. [Chemical Biology and Exposure; Wright, Aaron T. [Chemical Biology and Exposure

    2017-11-01

    Glutathione S-transferases (GSTs) comprise a highly diverse family of phase II drug metabolizing enzymes whose shared function is the conjugation of reduced glutathione to various endo- and xenobiotics. Although the conglomerate activity of these enzymes can be measured by colorimetric assays, measurement of the individual contribution from specific isoforms and their contribution to the detoxification of xenobiotics in complex biological samples has not been possible. For this reason, we have developed two activity-based probes that characterize active glutathione transferases in mammalian tissues. The GST active site is comprised of a glutathione binding “G site” and a distinct substrate binding “H site”. Therefore, we developed (1) a glutathione-based photoaffinity probe (GSH-ABP) to target the “G site”, and (2) a probe designed to mimic a substrate molecule and show “H site” activity (GST-ABP). The GSH-ABP features a photoreactive moiety for UV-induced covalent binding to GSTs and glutathione-binding enzymes. The GST-ABP is a derivative of a known mechanism-based GST inhibitor that binds within the active site and inhibits GST activity. Validation of probe targets and “G” and “H” site specificity was carried out using a series of competitors in liver homogenates. Herein, we present robust tools for the novel characterization of enzyme- and active site-specific GST activity in mammalian model systems.

  16. The cDNA sequence of a neutral horseradish peroxidase.

    Science.gov (United States)

    Bartonek-Roxå, E; Eriksson, H; Mattiasson, B

    1991-02-16

    A cDNA clone encoding a horseradish (Armoracia rusticana) peroxidase has been isolated and characterized. The cDNA contains 1378 nucleotides excluding the poly(A) tail and the deduced protein contains 327 amino acids which includes a 28 amino acid leader sequence. The predicted amino acid sequence is nine amino acids shorter than the major isoenzyme belonging to the horseradish peroxidase C group (HRP-C) and the sequence shows 53.7% identity with this isoenzyme. The described clone encodes nine cysteines of which eight correspond well with the cysteines found in HRP-C. Five potential N-glycosylation sites with the general sequence Asn-X-Thr/Ser are present in the deduced sequence. Compared to the earlier described HRP-C this is three glycosylation sites less. The shorter sequence and fewer N-glycosylation sites give the native isoenzyme a molecular weight of several thousands less than the horseradish peroxidase C isoenzymes. Comparison with the net charge value of HRP-C indicates that the described cDNA clone encodes a peroxidase which has either the same or a slightly less basic pI value, depending on whether the encoded protein is N-terminally blocked or not. This excludes the possibility that HRP-n could belong to either the HRP-A, -D or -E groups. The low sequence identity (53.7%) with HRP-C indicates that the described clone does not belong to the HRP-C isoenzyme group and comparison of the total amino acid composition with the HRP-B group does not place the described clone within this isoenzyme group. Our conclusion is that the described cDNA clone encodes a neutral horseradish peroxidase which belongs to a new, not earlier described, horseradish peroxidase group.

  17. Acute effects of heavy metals on the expression of glutathione-related antioxidant genes in the marine ciliate Euplotes crassus

    International Nuclear Information System (INIS)

    Kim, Se-Hun; Kim, Se-Joo; Lee, Jae-Seong; Lee, Young-Mi

    2014-01-01

    Highlights: • Significant higher increases in the relative ROS and total GSH levels were observed after exposure to heavy metals. • Real-time PCR data showed expression levels of GPx and GR mRNA were sensitively modulated within 8 h of exposure to heavy metals. • E. crassus GPx and GR genes may be involved in cellular defense mechanisms against heavy metal-induced oxidative stress. • E. crassus GPx and GR genes will be useful as potential molecular markers for monitoring heavy metal contamination. - Abstract: Euplotes crassus, a single-celled eukaryote, is directly affected by environmental contaminants. Here, exponentially cultured E. crassus were exposed to cadmium, copper, lead, and zinc and then the reactive oxygen species (ROS) and total glutathione (GSH) levels were measured. Subsequently, the transcriptional modulation of glutathione peroxidase (GPx) and glutathione reductase (GR) were estimated by quantitative RT-PCR. After an 8-h exposure, significantly higher increases in the relative ROS and total GSH levels were observed in exposed group, compared to the controls. Real-time PCR data revealed that the expression levels of GPx and GR mRNA were sensitively modulated within 8 h of exposure to all heavy metals. These findings suggest that these genes may be involved in cellular defense mechanisms by modulating their gene expression against heavy metal-induced oxidative stress. Thus, they may be useful as potential molecular biomarkers to assess sediment environments for contaminants

  18. Peroxidase activity in Spondias dulcis = Atividade da peroxidase em Spondias dulcis

    Directory of Open Access Journals (Sweden)

    Lúcio Cardozo-Filho

    2010-10-01

    Full Text Available In this study, the best conditions to obtain crude extracts showingPeroxidase activity from Spondia dulcis (caja-mango were evaluated. Fresh fruits (25 g were blended in different sodium phosphate buffer (0.05 to 0.2 M with a pH varying from 3.0 to 9.0. The muddy material was centrifuged for 20 minutes. In order to improve POD activity, the crude extract was submitted to precipitation with ammonium sulfate at 90% saturation. This precipitated was re-suspended in sodium phosphate buffer 0.2 M pH 6.5 and then, optimum pH for activity assay (pH varying from 5.0 to 9.0 and thermal stability (exposure to different temperatures varying from 30 to 75ºC for periods between 0 to 15 minutes were determined. The best conditions for activity assay were in phosphate buffer 0.2 M at pH7.0. The results obtained for thermal inactivation study suggest that the heating at 75ºCfor 15 minutes inactivated 95% of initial POD activity.Foram avaliadas, neste trabalho, algumas condições para a obtenção de extratos brutos com atividade peroxidase de Spondias dulcis (cajá-manga. Frutas frescas (25 g foram trituradas com tampão fosfato de sódio (0,05 a 0,2 M em pHs diferentes (3,0 a 9,0. O material obtido foi centrifugado por 20 min. O extrato bruto foi submetido à precipitação com sulfato de amônio até 90% de saturação. Este precipitado foi ressuspenso em tampão fosfato de sódio 0,2 M pH 6,5 e, assim, o pH ótimo para o ensaio de atividade (pH que varia de 5,0 a 9,0 e a estabilidade térmica (exposição a temperaturas de 30, 60, 65, 70 e 75ºC por um período de 0 a 15 min. deste foram determinados. As melhores condições encontradas para o ensaio de atividade foram em tampão fosfato 0,2 M pH 7,0. Os resultados para a inativação térmica sugerem que o aquecimento a 75ºC por 15 mininativa 95% da atividade de POD inicial.

  19. Glutathione-binding site of a bombyx mori theta-class glutathione transferase.

    Directory of Open Access Journals (Sweden)

    M D Tofazzal Hossain

    Full Text Available The glutathione transferase (GST superfamily plays key roles in the detoxification of various xenobiotics. Here, we report the isolation and characterization of a silkworm protein belonging to a previously reported theta-class GST family. The enzyme (bmGSTT catalyzes the reaction of glutathione with 1-chloro-2,4-dinitrobenzene, 1,2-epoxy-3-(4-nitrophenoxy-propane, and 4-nitrophenethyl bromide. Mutagenesis of highly conserved residues in the catalytic site revealed that Glu66 and Ser67 are important for enzymatic function. These results provide insights into the catalysis of glutathione conjugation in silkworm by bmGSTT and into the metabolism of exogenous chemical agents.

  20. Determination of glutathione and glutathione disulfide in biological samples: an in-depth review.

    Science.gov (United States)

    Monostori, Péter; Wittmann, Gyula; Karg, Eszter; Túri, Sándor

    2009-10-15

    Glutathione (GSH) is a thiol-containing tripeptide, which plays central roles in the defence against oxidative damage and in signaling pathways. Upon oxidation, GSH is transformed to glutathione disulfide (GSSG). The concentrations of GSH and GSSG and their molar ratio are indicators of cell functionality and oxidative stress. Assessment of redox homeostasis in various clinical states and medical applications for restoration of the glutathione status are of growing importance. This review is intended to provide a state-of-the-art overview of issues relating to sample pretreatment and choices for the separation and detection of GSH and GSSG. High-performance liquid chromatography, capillary electrophoresis and gas chromatography (as techniques with a separation step) with photometric, fluorimetric, electrochemical and mass spectrometric detection are discussed, stress being laid on novel approaches.

  1. Sex-, tissue-, and exposure duration-dependent effects of imidacloprid modulated by piperonyl butoxide and menadione in rats. Part I: oxidative and neurotoxic potentials.

    Science.gov (United States)

    Yardimci, Mustafa; Sevgiler, Yusuf; Rencuzogullari, Eyyup; Arslan, Mehmet; Buyukleyla, Mehmet; Yilmaz, Mehmet

    2014-12-01

    Earlier research has evidenced the oxidative and neurotoxic potential of imidacloprid, a neonicotinoid insecticide, in different animal species. The primary aim of this study was to determine how metabolic modulators piperonyl butoxide and menadione affect imidacloprid's adverse action in the liver and kidney of Sprague-Dawley rats of both sexes. The animals were exposed to imidacloprid alone (170 mg kg⁻¹) or in combination with piperonyl butoxide (100 mg kg⁻¹) or menadione (25 mg kg⁻¹) for 12 and 24 h. Their liver and kidney homogenates were analysed spectrophotometrically for glutathione peroxidase, glutathione S-transferase, catalase, total cholinesterase specific activities, total glutathione, total protein content, and lipid peroxidation levels. Imidacloprid displayed its prooxidative and neurotoxic effects predominantly in the kidney of male rats after 24 h of exposure. Our findings suggest that the observed differences in prooxidative and neurotoxic potential of imidacloprid could be related to differences in its metabolism between the sexes. Co-exposure (90-min pre-treatment) with piperonyl butoxide or menadione revealed tissue-specific effect of imidacloprid on total cholinesterase activity. Increased cholinesterase activity in the kidney could be an adaptive response to imidacloprid-induced oxidative stress. In the male rat liver, co-exposure with piperonyl butoxide or menadione exacerbated imidacloprid toxicity. In female rats, imidacloprid+menadione co-exposure caused prooxidative effects, while no such effects were observed with imidacloprid alone or menadione alone. In conclusion, sex-, tissue-, and duration-specific effects of imidacloprid are remarkable points in its toxicity.

  2. Self-Assembled Complexes of Horseradish Peroxidase with Magnetic Nanoparticles Showing Enhanced Peroxidase Activity

    KAUST Repository

    Corgié, Stéphane C.

    2012-02-15

    Bio-nanocatalysts (BNCs) consisting of horseradish peroxidase (HRP) self-assembled with magnetic nanoparticles (MNPs) enhance enzymatic activity due to the faster turnover and lower inhibition of the enzyme. The size and magnetization of the MNPs affect the formation of the BNCs, and ultimately control the activity of the bound enzymes. Smaller MNPs form small clusters with a low affinity for the HRP. While the turnover for the bound fraction is drastically increased, there is no difference in the H 2O 2 inhibitory concentration. Larger MNPs with a higher magnetization aggregate in larger clusters and have a higher affinity for the enzyme and a lower substrate inhibition. All of the BNCs are more active than the free enzyme or the MNPs (BNCs > HRP ≤laquo; MNPs). Since the BNCs show surprising resilience in various reaction conditions, they may pave the way towards new hybrid biocatalysts with increased activities and unique catalytic properties for magnetosensitive enzymatic reactions. Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  3. Subcellular distribution of glutathione and cysteine in cyanobacteria.

    Science.gov (United States)

    Zechmann, Bernd; Tomasić, Ana; Horvat, Lucija; Fulgosi, Hrvoje

    2010-10-01

    Glutathione plays numerous important functions in eukaryotic and prokaryotic cells. Whereas it can be found in virtually all eukaryotic cells, its production in prokaryotes is restricted to cyanobacteria and proteobacteria and a few strains of gram-positive bacteria. In bacteria, it is involved in the protection against reactive oxygen species (ROS), osmotic shock, acidic conditions, toxic chemicals, and heavy metals. Glutathione synthesis in bacteria takes place in two steps out of cysteine, glutamate, and glycine. Cysteine is the limiting factor for glutathione biosynthesis which can be especially crucial for cyanobacteria, which rely on both the sufficient sulfur supply from the growth media and on the protection of glutathione against ROS that are produced during photosynthesis. In this study, we report a method that allows detection and visualization of the subcellular distribution of glutathione in Synechocystis sp. This method is based on immunogold cytochemistry with glutathione and cysteine antisera and computer-supported transmission electron microscopy. Labeling of glutathione and cysteine was restricted to the cytosol and interthylakoidal spaces. Glutathione and cysteine could not be detected in carboxysomes, cyanophycin granules, cell walls, intrathylakoidal spaces, periplasm, and vacuoles. The accuracy of the glutathione and cysteine labeling is supported by two observations. First, preadsorption of the antiglutathione and anticysteine antisera with glutathione and cysteine, respectively, reduced the density of the gold particles to background levels. Second, labeling of glutathione and cysteine was strongly decreased by 98.5% and 100%, respectively, in Synechocystis sp. cells grown on media without sulfur. This study indicates a strong similarity of the subcellular distribution of glutathione and cysteine in cyanobacteria and plastids of plants and provides a deeper insight into glutathione metabolism in bacteria.

  4. Beta-amyloidolysis and glutathione in Alzheimer's disease

    Directory of Open Access Journals (Sweden)

    Lasierra-Cirujeda J

    2013-04-01

    Full Text Available J Lasierra-Cirujeda,1 P Coronel,2 MJ Aza,3 M Gimeno2 1CM Hematológico SC, Logroño, La Rioja, Spain; 2Tedec-Meiji Farma, SA, Alcalá de Henares, Madrid, Spain; 3Pharmaceutical Act, Ministry of Health, Regional Government, La Rioja, Spain Abstract: In this review, we hypothesized the importance of the interaction between the brain glutathione (GSH system, the proteolytic tissue plasminogen activator (t-PA/plasminogen/plasmin system, regulated by plasminogen activator inhibitor (PAI-1, and neuroserpin in the pathogenesis of Alzheimer's disease. The histopathological characteristic hallmark that gives personality to the diagnosis of Alzheimer's disease is the accumulation of neurofibroid tangles located intracellularly in the brain, such as the protein tau and extracellular senile plaques made primarily of amyloidal substance. These formations of complex etiology are intimately related to GSH, brain protective antioxidants, and the proteolytic system, in which t-PA plays a key role. There is scientific evidence that suggests a relationship between aging, a number of neurodegenerative disorders, and the excessive production of reactive oxygen species and accompanying decreased brain proteolysis. The plasminogen system in the brain is an essential proteolytic mechanism that effectively degrades amyloid peptides ("beta-amyloidolysis" through action of the plasmin, and this physiologic process may be considered to be a means of prevention of neurodegenerative disorders. In parallel to the decrease in GSH levels seen in aging, there is also a decrease in plasmin brain activity and a progressive decrease of t-PA activity, caused by a decrease in the expression of the t-PA together with an increase of the PAI-1 levels, which rise to an increment in the production of amyloid peptides and a lesser clearance of them. Better knowledge of the GSH mechanism and cerebral proteolysis will allow us to hypothesize about therapeutic practices. Keywords: glutathione

  5. Generic method for the absolute quantification of glutathione S-conjugates : Application to the conjugates of acetaminophen, clozapine and diclofenac

    NARCIS (Netherlands)

    den Braver, Michiel W.; Vermeulen, Nico P.E.; Commandeur, Jan N.M.

    2017-01-01

    Modification of cellular macromolecules by reactive drug metabolites is considered to play an important role in the initiation of tissue injury by many drugs. Detection and identification of reactive intermediates is often performed by analyzing the conjugates formed after trapping by glutathione

  6. Cross reactivities of rabbit anti-chicken horse radish peroxidase ...

    African Journals Online (AJOL)

    The cross reactivities of rabbit anti chicken horse radish peroxidase (conjugate) was tested with sera of Chicken, Ducks, Geese, Guinea fowl, Hawks, Pigeons and Turkeys in indirect enzyme linked immunosorbent assay (ELISA) technique. Sera from mammalian species (Bat, Equine and swine) were used as negative ...

  7. The glucose oxidase-peroxidase assay for glucose

    Science.gov (United States)

    The glucose oxidase-peroxidase assay for glucose has served as a very specific, sensitive, and repeatable assay for detection of glucose in biological samples. It has been used successfully for analysis of glucose in samples from blood and urine, to analysis of glucose released from starch or glycog...

  8. Calorimetric studies of the thermal denaturation of cytochrome c peroxidase

    International Nuclear Information System (INIS)

    Kresheck, G.C.; Erman, J.E.

    1988-01-01

    Two endotherms are observed by differential scanning calorimetry during the thermal denaturation of cytochrome c peroxidase at pH 7.0. The transition midpoint temperatures (t/sub m/) were 43.9 +- 1.4 and 63.3 +- 1.6 0 C, independent of concentration. The two endotherms were observed at all pH values between 4 and 8, with the transition temperatures varying with pH. Precipitation was observed between pH 4 and 6, and only qualitative data are presented for this region. The thermal unfolding of cytochrome c peroxidase was sensitive to the presence and ligation state of the heme. Only a single endotherm was observed for the unfolding of the apoprotein, and this transition was similar to the high-temperature transition in the holoenzyme. Addition of KCN to the holoenzyme increases the midpoint of the high-temperature transition whereas the low-temperature transition was increased upon addition of KF. Binding of the natural substrate ferricytochrome c to the enzyme increases the low-temperature transition by 4.8 +- 1.3 0 C but has no effect on the high-temperature transition at pH 7. The presence of cytochrome c peroxidase decreases the stability of cytochrome c, and both proteins appear to unfold simultaneously. The results are discussed in terms of the two domains evident in the X-ray crystallographic structure of cytochrome c peroxidase

  9. Polyamines, peroxidase and proteins involved in the senescence ...

    African Journals Online (AJOL)

    Senescence is the natural aging process at the cellular level or range of phenomena associated with this process. The objective of this review was to show the involvement of substances that may be related to senescence in plants, such as polyamines, peroxidase and proteins. These substances were related with the ...

  10. Decolourization of Direct Blue 2 by peroxidases obtained from an ...

    African Journals Online (AJOL)

    Also, an increase in toxicity, determined by Vibrio fisheri, was observed after the enzymatic oxidation of the dye. Results suggest that the oxidation of DB2 with peroxidases can be recommended as a pretreatment step before a conventional treatment process. Keywords: decolourization, Direct Blue 2, industrial waste, ...

  11. Molecular cloning and characterization of a new peroxidase gene ...

    African Journals Online (AJOL)

    length cDNA of O.violaceus peroxidase gene (OvRCI, GenBank. Acc. No. AY428037) was 1220 bp and contained an 1128 bp open reading frame encoding a protein of 375 amino acids. Homology analysis and molecular modeling revealed that ...

  12. Isolation of an ascorbate peroxidase in Brassica napus and analysis ...

    African Journals Online (AJOL)

    USER

    2010-04-05

    Apr 5, 2010 ... domain; APX, ascorbate peroxidase; Bn-APX, Brassica napus ascorbate ... Brassica napus, which is widely grown as the oilseed crop of rape or canola, .... grew on the SD-Leu-Trp-His-Ade medium and were verified by PCR.

  13. Effect of heat treatment on polyphenol oxidase and peroxidase ...

    African Journals Online (AJOL)

    Effect of heat treatment (55°C/20 min) on polyphenol oxidase (PPO) and peroxidase (POD) activities and total phenolic compounds was investigated in Algerian dates (Deglet Nour variety) at Tamar (fully ripe) stage and in dates stored for 5 months at ambient temperature and in cold storage (10°C). Results obtained ...

  14. 21 CFR 864.7675 - Leukocyte peroxidase test.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Leukocyte peroxidase test. 864.7675 Section 864.7675 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES HEMATOLOGY AND PATHOLOGY DEVICES Hematology Kits and Packages § 864.7675 Leukocyte...

  15. Effect of industrial wastewater ontotal protein and the peroxidase ...

    African Journals Online (AJOL)

    The aim of this study is to investigate the effects of industrial wastewaters on protein and the peroxidase activity in Lycopersicon esculentum Mill., Capsicum annuum L., Phaseolus vulgaris L. and Vicia faba L. Industrial wastewaters were taken from Dardanel Fisheries Company, Tekel alcoholic drinks companies' ...

  16. Efficient production of Arthromyces ramosus peroxidase by Aspergillus awamori

    NARCIS (Netherlands)

    Lokman, B.C.; Joosten, V.; Hovenkamp, J.; Gouka, R.J.; Verrips, C.T.; Hondel, C.A.M.J.J. van den

    2003-01-01

    The heterologous production of Arthromyces ramosus peroxidase (ARP) was analysed in the filamentous fungus Aspergillus awamori under control of the inducible endoxylanase promoter. Secretion of active ARP was achieved up to 800 mg l-1 in shake flask cultures. Western blot analysis showed that an

  17. Frequency of anti thyroid peroxidase antibody in patients of vitiligo

    International Nuclear Information System (INIS)

    Zhokhar, A.; Shaikh, Z.I.

    2013-01-01

    Objective: The objective of this study was to compare the frequency of anti thyroid peroxidase antibody in patients suffering from vitiligo with healthy control group. Type of Study: Case control study. Settings: Dermatology Department, Military Hospital, Rawalpindi, from 20th March 2010 to 20th July 2011. Material and Methods: Fifty clinically diagnosed patients of vitiligo, age = 18 yrs and both genders with no history of thyroid disease, past or current use of drugs for thyroid disorder or thyroid surgery were included as cases (Group A). Fifty healthy individuals with no evidence of vitiligo or thyroid disorder on history and physical examination and with no family history of vitiligo, matched for age and gender with cases, were included as control (Group B). Serum anti thyroid peroxidase (anti TPO) antibodies were measured using enzyme linked immunosorbent assay (ELISA) in both cases and control. Results: Eight (16%) patients in Group A were anti-thyroid peroxidase antibody positive and forty two (84%) patients were negative while one (2%) patient was anti-thyroid peroxidase antibody positive in Group B and forty nine (98%) patients were negative (p = 0.001). Conclusion: Anti TPO antibody is significantly more common in patients of vitiligo as compared to general population. (author)

  18. Thylakoid-bound ascorbate peroxidase increases resistance to salt ...

    African Journals Online (AJOL)

    Reactive oxygen species (ROS) are cellular indicators of stress. In plants, they function as secondary messengers in response to environmental stress. Ascorbate peroxidase (APX) is an important enzyme directly involved in the scavenging of ROS. In this study, we aimed at identifying the function of the Brassica napus ...

  19. Effect of rosella ( Hibiscus sabdariffa L ) extract on glutathione-S ...

    African Journals Online (AJOL)

    Purpose: To determine the effect of rosella (Hibiscus sabdariffa L) extract on glutathione-S-trasferase (GST) activity and its hepatoprotective effect. Methods: A total of 25 rats were divided randomly into 5 groups (5 rats per group). Group I served as the baseline, group II was the negative control group, while groups III, IV and ...

  20. Candida albicans biofilm on titanium: effect of peroxidase precoating

    Directory of Open Access Journals (Sweden)

    Mohamed Ahariz

    2010-08-01

    Full Text Available Mohamed Ahariz1, Philippe Courtois1,21Laboratory of Experimental Hormonology, Université Libre de Bruxelles, Brussels, 2UER de Biologie Médicale, Haute Ecole Francisco Ferrer, Brussels, BelgiumAbstract: The present study aimed to document Candida albicans biofilm development on titanium and its modulation by a peroxidase-precoated material which can generate antimicrobials, such as hypoiodite or hypothiocyanite, from hydrogen peroxide, iodide, or thiocyanate. For this purpose, titanium (powder or foil was suspended in Sabouraud liquid medium inoculated with C. albicans ATCC10231. After continuous stirring for 2–21 days at room temperature, the supernatant was monitored by turbidimetry at 600 nm and titanium washed three times in sterile Sabouraud broth. Using the tetrazolium salt MTT-formazan assay, the titanium-adherent fungal biomass was measured as 7.50 ± 0.60 × 106 blastoconidia per gram of titanium powder (n = 30 and 0.50 ± 0.04 × 106 blastoconidia per cm² of titanium foil (n = 12. The presence of yeast on the surface of titanium was confirmed by microscopy both on fresh preparations and after calcofluor white staining. However, in the presence of peroxidase systems (lactoperoxidase with substrates such as hydrogen peroxide donor, iodide, or thiocyanate, Candida growth in both planktonic and attached phases appeared to be inhibited. Moreover, this study demonstrates the possible partition of peroxidase systems between titanium material (peroxidase-precoated and liquid environment (containing peroxidase substrates to limit C. albicans biofilm formation.Keywords: adhesion, material, oral, yeast

  1. Superoxide radical (O2-) reactivity with respect to glutathione

    International Nuclear Information System (INIS)

    Sekaki, A.; Gardes-Albert, M.; Ferradini, C.

    1984-01-01

    Influence of superoxide radicals formed during gamma irradiation of glutathione in aerated aqueous solutions is examined. Solutions are buffered at pH7 and contain sodium formate for capture of H and OH radicals which are transformed in COO - radicals and then O 2 - radicals. G value of glutathione disparition vs glutathione concentration are given with and without enzyme or catalase. Reaction mechanism are interpreted [fr

  2. Profiling of wheat class III peroxidase genes derived from powdery mildew-attacked epidermis reveals distinct sequence-associated expression patterns.

    Science.gov (United States)

    Liu, Guosheng; Sheng, Xiaoyan; Greenshields, David L; Ogieglo, Adam; Kaminskyj, Susan; Selvaraj, Gopalan; Wei, Yangdou

    2005-07-01

    A cDNA library was constructed from leaf epidermis of diploid wheat (Triticum monococcum) infected with the powdery mildew fungus (Blumeria graminis f. sp. tritici) and was screened for genes encoding peroxidases. From 2,500 expressed sequence tags (ESTs), 36 cDNAs representing 10 peroxidase genes (designated TmPRX1 to TmPRX10) were isolated and further characterized. Alignment of the deduced amino acid sequences and phylogenetic clustering with peroxidases from other plant species demonstrated that these peroxidases fall into four distinct groups. Differential expression and tissue-specific localization among the members were observed during the B. graminis f. sp. tritici attack using Northern blots and reverse-transcriptase polymerase chain reaction analyses. Consistent with its abundance in the EST collection, TmPRX1 expression showed the highest induction during pathogen attack and fluctuated in response to the fungal parasitic stages. TmPRX1 to TmPRX6 were expressed predominantly in mesophyll cells, whereas TmPRX7 to TmPRX10, which feature a putative C-terminal propeptide, were detectable mainly in epidermal cells. Using TmPRX8 as a representative, we demonstrated that its C-terminal propeptide was sufficient to target a green fluorescent protein fusion protein to the vacuoles in onion cells. Finally, differential expression profiles of the TmPRXs after abiotic stresses and signal molecule treatments were used to dissect the potential role of these peroxidases in multiple stress and defense pathways.

  3. Induction of Laccase, Lignin Peroxidase and Manganese Peroxidase Activities in White-Rot Fungi Using Copper Complexes

    Directory of Open Access Journals (Sweden)

    Martina Vrsanska

    2016-11-01

    Full Text Available Ligninolytic enzymes, such as laccase, lignin peroxidase and manganese peroxidase, are biotechnologically-important enzymes. The ability of five white-rot fungal strains Daedaleopsis confragosa, Fomes fomentarius, Trametes gibbosa, Trametes suaveolens and Trametes versicolor to produce these enzymes has been studied. Three different copper(II complexes have been prepared ((Him[Cu(im4(H2O2](btc·3H2O, where im = imidazole, H3btc = 1,3,5-benzenetricarboxylic acid, [Cu3(pmdien3(btc](ClO43·6H2O and [Cu3(mdpta3(btc](ClO43·4H2O, where pmdien = N,N,N′,N′′,N′′-pentamethyl-diethylenetriamine and mdpta = N,N-bis-(3-aminopropylmethyl- amine, and their potential application for laccase and peroxidases induction have been tested. The enzyme-inducing activities of the complexes were compared with that of copper sulfate, and it has been found that all of the complexes are suitable for the induction of laccase and peroxidase activities in white-rot fungi; however, the newly-synthesized complex M1 showed the greatest potential for the induction. With respect to the different copper inducers, this parameter seems to be important for enzyme activity, which depends also on the fungal strains.

  4. Evaluation of chlorpyrifos toxicity through a 28-day study: Cholinesterase activity, oxidative stress responses, parent compound/metabolite levels, and primary DNA damage in blood and brain tissue of adult male Wistar rats.

    Science.gov (United States)

    Kopjar, Nevenka; Žunec, Suzana; Mendaš, Gordana; Micek, Vedran; Kašuba, Vilena; Mikolić, Anja; Lovaković, Blanka Tariba; Milić, Mirta; Pavičić, Ivan; Čermak, Ana Marija Marjanović; Pizent, Alica; Lucić Vrdoljak, Ana; Želježić, Davor

    2018-01-05

    In this 28 day-study, we evaluated the effects of the insecticide chlorpyrifos orally administered to Wistar rats at doses 0.160, 0.015, and 0.010 mg/kg b. w./day. Following treatment, total cholinesterase activity and activities of acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) were measured. Oxidative stress responses were evaluated using a battery of endpoints to establish lipid peroxidation, changes in total antioxidant capacity, level of reactive oxygen species (ROS), glutathione (GSH) level and activities of glutathione peroxidase (GSH-Px), superoxide dismutase (SOD) and catalase. Using HPLC-UV DAD analysis, levels of the parent compound and its main metabolite 3,5,6-trichloro-2-pyridinol in plasma and brain tissue were measured. The genotoxic effect was estimated using alkaline comet assay in leukocytes and brain tissue. The exposure did not result in significant effects on total cholinesterase, AChE and BChE activity in plasma and brain tissue. Lipid peroxidation slightly increased both in plasma and brain tissue. Total antioxidant capacity, ROS and GSH levels were marginally influenced by the exposure. Treatment led to significant increases of GSH-Px activity in blood, SOD activity in erythrocytes and a slight increase of catalase activity in plasma. HPLC-UV DAD analysis revealed the presence of both the parent compound and its main metabolite in the plasma of all of the experimental animals and brain tissue of the animals treated at the two higher doses. All of the tested doses of chlorpyrifos were slightly genotoxic, both to leukocytes and brain tissue. Our results call for further research using other sensitive biomarkers of effect, along with different exposure scenarios. Copyright © 2017 Elsevier B.V. All rights reserved.

  5. Ligninolytic enzymes of the fungus Irpex lacteus (Polyporus tulipiferae): isolation and characterization of lignin peroxidase

    Czech Academy of Sciences Publication Activity Database

    Rothschild, N.; Novotný, Čeněk; Šašek, Václav; Dosoretz, C. G.

    2002-01-01

    Roč. 31, - (2002), s. 627-633 ISSN 0141-0229 Institutional research plan: CEZ:AV0Z5020903 Keywords : lignin * peroxidase * heme peroxidase Subject RIV: EE - Microbiology, Virology Impact factor: 1.773, year: 2002

  6. The Incomplete Glutathione Puzzle: Just Guessing at Numbers and Figures?

    Science.gov (United States)

    Deponte, Marcel

    2017-11-20

    Glutathione metabolism is comparable to a jigsaw puzzle with too many pieces. It is supposed to comprise (i) the reduction of disulfides, hydroperoxides, sulfenic acids, and nitrosothiols, (ii) the detoxification of aldehydes, xenobiotics, and heavy metals, and (iii) the synthesis of eicosanoids, steroids, and iron-sulfur clusters. In addition, glutathione affects oxidative protein folding and redox signaling. Here, I try to provide an overview on the relevance of glutathione-dependent pathways with an emphasis on quantitative data. Recent Advances: Intracellular redox measurements reveal that the cytosol, the nucleus, and mitochondria contain very little glutathione disulfide and that oxidative challenges are rapidly counterbalanced. Genetic approaches suggest that iron metabolism is the centerpiece of the glutathione puzzle in yeast. Furthermore, recent biochemical studies provide novel insights on glutathione transport processes and uncoupling mechanisms. Which parts of the glutathione puzzle are most relevant? Does this explain the high intracellular concentrations of reduced glutathione? How can iron-sulfur cluster biogenesis, oxidative protein folding, or redox signaling occur at high glutathione concentrations? Answers to these questions not only seem to depend on the organism, cell type, and subcellular compartment but also on different ideologies among researchers. A rational approach to compare the relevance of glutathione-dependent pathways is to combine genetic and quantitative kinetic data. However, there are still many missing pieces and too little is known about the compartment-specific repertoire and concentration of numerous metabolites, substrates, enzymes, and transporters as well as rate constants and enzyme kinetic patterns. Gathering this information might require the development of novel tools but is crucial to address potential kinetic competitions and to decipher uncoupling mechanisms to solve the glutathione puzzle. Antioxid. Redox Signal

  7. Tissue specific responses to cadmium-based quantum dots in the marine mussel Mytilus galloprovincialis

    Energy Technology Data Exchange (ETDEWEB)

    Rocha, Thiago Lopes [CIMA, Faculty of Science and Technology, University of Algarve, Campus de Gambelas, 8005-139 Faro (Portugal); Gomes, Tânia [CIMA, Faculty of Science and Technology, University of Algarve, Campus de Gambelas, 8005-139 Faro (Portugal); Norwegian Institute for Water Research (NIVA), Gaustadalléen 21, NO-0349 Oslo (Norway); Mestre, Nélia C.; Cardoso, Cátia [CIMA, Faculty of Science and Technology, University of Algarve, Campus de Gambelas, 8005-139 Faro (Portugal); Bebianno, Maria João, E-mail: mbebian@ualg.pt [CIMA, Faculty of Science and Technology, University of Algarve, Campus de Gambelas, 8005-139 Faro (Portugal)

    2015-12-15

    Highlights: • Mussel gills are the main target for oxidative stress induced by Cd-based QDs. • Antioxidants responses induced by Cd-based QDs and dissolved Cd are mediated by different mechanisms. • CdTe QDs are more pro-oxidant Cd form when compared to dissolved Cd. • Differential tissue response indicated nano-specific effects. - Abstract: In recent years, Cd-based quantum dots (QDs) have generated interest from the life sciences community due to their potential applications in nanomedicine, biology and electronics. However, these engineered nanomaterials can be released into the marine environment, where their environmental health hazards remain unclear. This study investigated the tissue-specific responses related to alterations in the antioxidant defense system induced by CdTe QDs, in comparison with its dissolved counterpart, using the marine mussel Mytilus galloprovincialis. Mussels were exposed to CdTe QDs and dissolved Cd for 14 days at 10 μgCd L{sup −1} and biomarkers of oxidative stress [superoxide dismutase (SOD), catalase (CAT), glutathione peroxidases (total, Se-independent and Se-dependent GPx) and glutathione-S-transferase (GST) activities] were analyzed along with Cd accumulation in the gills and digestive gland of mussels. Results show that both Cd forms changed mussels’ antioxidant responses with distinct modes of action (MoA). There were tissue- and time-dependent differences in the biochemical responses to each Cd form, wherein QDs are more pro-oxidant when compared to dissolved Cd. The gills are the main tissue affected by QDs, with effects related to the increase of SOD, GST and GPx activities, while those of dissolved Cd was associated to the increase of CAT activity, Cd accumulation and exposure time. Digestive gland is a main tissue for accumulation of both Cd forms, but changes in antioxidant enzyme activities are smaller than in gills. A multivariate analysis revealed that the antioxidant patterns are tissue dependent

  8. Glutathione attenuates uranyl toxicity in Lactococcus lactis

    Energy Technology Data Exchange (ETDEWEB)

    Fahmy, Karim; Oertel, Jana [Helmholtz-Zentrum Dresden-Rossendorf e.V., Dresden (Germany). Biophysics; Obeid, M. [Technische Univ. Dresden (Germany); Solioz, M. [Bern Univ. (Switzerland)

    2017-06-01

    We investigated the role of intracellular glutathione (GSH), which in a large number of taxa plays a role in the protection against the toxicity of heavy metals. Anaerobically grown Lactococcus lactis containing an inducible GSH synthesis pathway was used as a model organism allowing the study of GSH-dependent uranyl detoxification without interference from additional reactive oxygen species. Microcalorimetric measurements of the metabolic heat showed that intracellular GSH attenuates the toxicity of uranium at a concentration in the range of 10-150 μM. Isothermal titration calorimetry revealed the endothermic binding of U(VI) to the carboxyl group(s) of GSH. The data indicate that the primary detoxifying mechanism is the intracellular sequestration of carboxyl-coordinated U(VI) into an insoluble complex with GSH.

  9. Transport of glutathione into the nucleus.

    Science.gov (United States)

    Queval, Guillaume; Foyer, Christine

    2014-10-01

    The tripeptide thiol glutathione (GSH) is present in the nucleus of plant and animal cells. However, the functions of GSH in the nucleus remain poorly characterised. GSH appears to become sequestered in the nucleus at the early stages of the cell cycle. As part of our search for proteins that may be involved in GSH transport into the nucleus, we studied the functions of the nucleoporin called Alacrima Achalasia aDrenal Insufficiency Neurologic disorder (ALADIN). ALADIN is encoded by the Achalasia-Addisonianism-Alacrimia (AAAS) gene in mammalian cells. Defects in ALADIN promote adrenal disorders and lead to the triple A syndrome in humans. The ALADIN protein localizes to the nuclear envelope in Arabidopsis thaliana and interacts with other components of the nuclear pore complex (NPC). We characterised the functions of the ALADIN protein in an Arabidopsis thaliana T-DNA insertion knockout mutant, which shows slow growth compared to the wild type. Copyright © 2014. Published by Elsevier Inc.

  10. Reduction of intracellular glutathione content and radiosensitivity

    International Nuclear Information System (INIS)

    Vos, O.; Schans, G.P. van der; Roos-Verheij, W.S.D.

    1986-05-01

    The intracellular glutathione (GSH) content in HeLa, CHO and V79 cells was reduced by incubating the cells in growth medium containing buthionine sulfoximine (BSO) or diethyl maleate (DEM). Clonogenicity, single strand DNA breaks (ssb) and double strand DNA breaks (dsb) were used as criteria for radiation induced damage after X- or γ irradiation. In survival experiments DEM gave a slightly larger sensitization although it gave a smaller reduction of the intracellular GSH. In general, sensitization was larger for dsb than for ssb, also the reduction of the OER was generally larger for dsb than for ssb. This may be due to the higher dose rate in case of dsb experiments resulting in a higher rate of radiochemical oxygen consumption. In general, no effect was found on post-irradiation repair of ssb and dsb. (Auth.)

  11. Reduction of intracellular glutathione content and radiosensitivity

    International Nuclear Information System (INIS)

    Vos, O.; Schans, G.P. van der; Roos-Verheij, W.S.D.

    1986-01-01

    The intracellular glutathione (GSH) content of HeLa, CHO and V79 cells was reduced by incubating the cells in growth medium containing buthionine sulphoximine or diethyl maleate (DEM). Clonogenicity, single-strand DNA breaks (ssb) and double-strand DNA breaks (dsb) were used as criteria for radiation-induced damage after X- or γ-irradiation. In survival experiments, DEM gave a slightly larger sensitization although it gave a smaller reduction of the intracellular GSH. In general, sensitization was larger for dsb than for ssb, also the reduction of the o.e.r. was generally larger for dsb than for ssb. This may be due to the higher dose rate in case of dsb experiments resulting in a higher rate of radiochemical oxygen consumption. In general, no effect was found on post-irradiation repair of ssb and dsb. (author)

  12. Misonidazole-glutathione conjugates in CHO cells

    International Nuclear Information System (INIS)

    Varghese, A.J.; Whitmore, G.F.

    1984-01-01

    Misonidazole, after reduction to the hydroxylamine derivative, reacts with glutathione (GSH) under physiological conditions. The reaction product has been identified as a mixture of two isomeric conjugates. When water soluble extracts of CHO cells exposed to misonidazole under hypoxic conditions are subjected to HPLC analysis, misonidazole derivatives, having the same chromatographic properties as the GSH-MISO conjugates, were detected. When CHO cells were incubated with misonidazole in the presence of added GSH, a substantial increase in the amount of the conjugate was detected. When extracts of CHO cells exposed to misonidazole under hypoxia were subsequently exposed to GSH, an increased formation of the conjugate was observed. A rearrangement product of the hydroxylamine derivative of misonidazole is postulated as the reactive intermediate responsible for the formation of the conjugate

  13. Glutathione attenuates uranyl toxicity in Lactococcus lactis

    International Nuclear Information System (INIS)

    Fahmy, Karim; Oertel, Jana; Solioz, M.

    2017-01-01

    We investigated the role of intracellular glutathione (GSH), which in a large number of taxa plays a role in the protection against the toxicity of heavy metals. Anaerobically grown Lactococcus lactis containing an inducible GSH synthesis pathway was used as a model organism allowing the study of GSH-dependent uranyl detoxification without interference from additional reactive oxygen species. Microcalorimetric measurements of the metabolic heat showed that intracellular GSH attenuates the toxicity of uranium at a concentration in the range of 10-150 μM. Isothermal titration calorimetry revealed the endothermic binding of U(VI) to the carboxyl group(s) of GSH. The data indicate that the primary detoxifying mechanism is the intracellular sequestration of carboxyl-coordinated U(VI) into an insoluble complex with GSH.

  14. Fenóis totais, peroxidase e suas relações com a compatibilidade de mudas de pessegueiro interenxertadas Total phenols content, peroxidase activity and their relationship with the compatibility of the intergrafted seedlings of peach tree

    Directory of Open Access Journals (Sweden)

    Charles Allan Telles

    2009-02-01

    vegetative growth and dormancy period. Samples of bark were processed and quantified by spectrophotometry. The treatments included the combination of two rootstocks ('Okinawa' and 'Capdeboscq', two interstock (plum tree 'Irati' and 'Reubennel' and two scions ('Chimarrita' and 'Coral', and the Japanese apricot and cherry 'Capulin' cultivated at Embrapa Technology Transfer Station, Canoinhas-SC. The experimental design was the completely randomized blocks with three replications, each one with three plants. The peroxidase activity and total phenols content presented low variation between the peach tree and the plum tree, being compatible among them. Tissues collected during the dormancy period showed greater peroxidase activity than tissues from vegetative phase. The Japanese apricot and cherry present high incompatibility when grafted on peach rootstock.

  15. Purification and characterization of an intracellular peroxidase from Streptomyces cyaneus.

    OpenAIRE

    Mliki, A; Zimmermann, W

    1992-01-01

    An intracellular peroxidase (EC 1.11.1.7) from Streptomyces cyaneus was purified to homogeneity. The enzyme had a molecular weight of 185,000 and was composed of two subunits of equal size. It had an isoelectric point of 6.1. The enzyme had a peroxidase activity toward o-dianisidine with a Km of 17.8 microM and a pH optimum of 5.0. It also showed catalase activity with a Km of 2.07 mM H2O2 and a pH optimum of 8.0. The purified enzyme did not catalyze C alpha-C beta bond cleavage of 1,3-dihydr...

  16. Response of Glutathione and Glutathione S-transferase in Rice Seedlings Exposed to Cadmium Stress

    Directory of Open Access Journals (Sweden)

    Chun-hua ZHANG

    2008-03-01

    Full Text Available A hydroponic culture experiment was done to investigate the effect of Cd stress on glutathione content (GSH and glutathione S-transferase (GST, EC 2.5.1.18 activity in rice seedlings. The rice growth was severely inhibited when Cd level in the solution was higher than 10 mg/L. In rice shoots, GSH content and GST activity increased with the increasing Cd level, while in roots, GST was obviously inhibited by Cd treatments. Compared with shoots, the rice roots had higher GSH content and GST activity, indicating the ability of Cd detoxification was much higher in roots than in shoots. There was a significant correlation between Cd level and GSH content or GST activity, suggesting that both parameters may be used as biomarkers of Cd stress in rice.

  17. Compartment specific importance of glutathione during abiotic and biotic stress

    Directory of Open Access Journals (Sweden)

    Bernd eZechmann

    2014-10-01

    Full Text Available The tripeptide thiol glutathione (γ-L-glutamyl-L-cysteinyl-glycine is the most important sulfur containing antioxidant in plants and essential for plant defense against abiotic and biotic stress conditions. It is involved in the detoxification of reactive oxygen species, redox signaling, the modulation of defense gene expression and important for the regulation of enzymatic activities. Even though changes in glutathione contents are well documented in plants and its roles in plant defense are well established, still too little is known about its compartment specific importance during abiotic and biotic stress conditions. Due to technical advances in the visualization of glutathione and the redox state of plants through microscopical methods some progress was made in the last few years in studying the importance of subcellular glutathione contents during stress conditions in plants. This review summarizes the data available on compartment specific importance of glutathione in the protection against abiotic and biotic stress conditions such as high light stress, exposure to cadmium, drought, and pathogen attack (Pseudomonas, Botrytis, Tobacco Mosaic Virus. The data will be discussed in connection with the subcellular accumulation of ROS during these conditions and glutathione synthesis which are both highly compartment specific (e.g. glutathione synthesis takes place in chloroplasts and the cytosol. Thus this review will reveal the compartment specific importance of glutathione during abiotic and biotic stress conditions.

  18. Glutathione Redox System in β-Thalassemia/Hb E Patients

    Directory of Open Access Journals (Sweden)

    Ruchaneekorn W. Kalpravidh

    2013-01-01

    Full Text Available β-thalassemia/Hb E is known to cause oxidative stress induced by iron overload. The glutathione system is the major endogenous antioxidant that protects animal cells from oxidative damage. This study aimed to determine the effect of disease state and splenectomy on redox status expressed by whole blood glutathione (GSH/glutathione disulfide (GSSG and also to evaluate glutathione-related responses to oxidation in β-thalassemia/Hb E patients. Twenty-seven normal subjects and 25 β-thalassemia/Hb E patients were recruited and blood was collected. The GSH/GSSG ratio, activities of glutathione-related enzymes, hematological parameters, and serum ferritin levels were determined in individuals. Patients had high iron-induced oxidative stress, shown as significantly increased serum ferritin, a decreased GSH/GSSG ratio, and increased activities of glutathione-related enzymes. Splenectomy increased serum ferritin levels and decreased GSH levels concomitant with unchanged glutathione-related enzyme activities. The redox ratio had a positive correlation with hemoglobin levels and negative correlation with levels of serum ferritin. The glutathione system may be the body’s first-line defense used against oxidative stress and to maintain redox homeostasis in thalassemic patients based on the significant correlations between the GSH/GSSH ratio and degree of anemia or body iron stores.

  19. 21 CFR 864.7375 - Glutathione reductase assay.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Glutathione reductase assay. 864.7375 Section 864.7375 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES HEMATOLOGY AND PATHOLOGY DEVICES Hematology Kits and Packages § 864.7375 Glutathione...

  20. Potential Applications of Peroxidases in the Fine Chemical Industries

    Science.gov (United States)

    Casella, Luigi; Monzani, Enrico; Nicolis, Stefania

    A description of selected types of reactions catalyzed by heme peroxidases is given. In particular, the discussion is focused mainly on those of potential interest for fine chemical synthesis. The division into subsections has been done fromthe point of view of the enzyme action, i.e., giving emphasis to themechanismof the enzymatic reaction, and from that of the substrate, i.e., analyzing the type of transformation promoted by the enzyme. These two approaches have several points in common.

  1. Kinetic mechanism and nucleotide specificity of NADH peroxidase

    International Nuclear Information System (INIS)

    Stoll, V.S.; Blanchard, J.S.

    1988-01-01

    NADH peroxidase is a flavoprotein isolated from Streptococcus faecalis which catalyzes the pyridine nucleotide-dependent reduction of hydrogen peroxide to water. Initial velocity, product, and dead-end inhibition studies have been performed at pH 7.5 and support a ping-pong kinetic mechanism. In the absence of hydrogen peroxide, both transhydrogenation between NADH and thioNAD, and isotope exchange between [ 14 C]NADH and NAD, have been demonstrated, although in both these experiments, the maximal velocity of nucleotide exchange was less than 1.5% the maximal velocity of the peroxidatic reaction. We propose that NADH binds tightly to both oxidized and two-electron reduced enzyme. NADH oxidation proceeds stereospecifically with the transfer of the 4S hydrogen to enzyme, and then, via exchange, to water. No primary tritium kinetic isotope effect was observed, and no statistically significant primary deuterium kinetic isotope effects on V/K were determined, although primary deuterium kinetic isotope effects on V were observed in the presence and absence of sodium acetate. NADH peroxidase thus shares with other flavoprotein reductases striking kinetic, spectroscopic, and stereochemical similarities. On this basis, we propose a chemical mechanism for the peroxide cleaving reaction catalyzed by NADH peroxidase which involves the obligate formation of a flavinperoxide, and peroxo bond cleavage by nucleophilic attack by enzymatic dithiols

  2. DYNAMICS OF LEAF PEROXIDASE ACTIVITY DURING ONTOGENY OF HEMP PLANTS, IN RELATION TO SEXUAL PHENOTYPE

    Directory of Open Access Journals (Sweden)

    Elena Truta

    2005-08-01

    Full Text Available During vegetation of female and male hemp plants (Cannabis sativa L., five quantitative determinations of peroxidase activities were made (40 days, 55 days, 70 days, 85 days, 105 days. Peroxidase activity presented some differences in hemp plants, between females and males, during their vegetation cycle. In female plants, before anthesis were registered peaks of peroxidase activities. The blossoming of male plants was coincident with the increase of catalitic action of peroxidase. Generally, the male plants displayed greater levels of peroxidasic activity.

  3. Hairy root transgene expression analysis of a secretory peroxidase (PvPOX1) from common bean infected by Fusarium wilt.

    Science.gov (United States)

    Xue, Renfeng; Wu, Xingbo; Wang, Yingjie; Zhuang, Yan; Chen, Jian; Wu, Jing; Ge, Weide; Wang, Lanfen; Wang, Shumin; Blair, Matthew W

    2017-07-01

    Plant peroxidases (POXs) are one of the most important redox enzymes in the defense responses. However, the large number of different plant POX genes makes it necessary to carefully confirm the function of each paralogous POX gene in specific tissues and disease interactions. Fusarium wilt is a devastating disease of common bean caused by Fusarium oxysporum f. sp. phaseoli. In this study, we evaluated a peroxidase gene, PvPOX1, from a resistant common bean genotype, CAAS260205 and provided direct evidence for PvPOX1's role in resistance by transforming the resistant allele into a susceptible common bean genotype, BRB130, via hairy root transformation using Agrobacterium rhizogenes. Analysis of PvPOX1 gene over-expressing hairy roots showed it increased resistance to Fusarium wilt both in the roots and the rest of transgenic plants. Meanwhile, the PvPOX1 expressive level, the peroxidase activity and hydrogen peroxide (H 2 O 2 ) accumulation were also enhanced in the interaction. The result showed that the PvPOX1 gene played an essential role in Fusarium wilt resistance through the occurrence of reactive oxygen species (ROS) induced hypersensitive response. Therefore, PvPOX1 expression was proven to be a valuable gene for further analysis which can strengthen host defense response against Fusarium wilt through a ROS activated resistance mechanism. Copyright © 2017 Elsevier B.V. All rights reserved.

  4. The poplar phi class glutathione transferase: expression, activity and structure of GSTF1

    Directory of Open Access Journals (Sweden)

    Henri ePégeot

    2014-12-01

    Full Text Available Glutathione transferases (GSTs constitute a superfamily of enzymes with essential roles in cellular detoxification and secondary metabolism in plants as in other organisms. Several plant GSTs, including those of the Phi class (GSTFs, require a conserved catalytic serine residue to perform glutathione (GSH-conjugation reactions. Genomic analyses revealed that terrestrial plants have around 10 GSTFs, 8 in the Populus trichocarpa genome, but their physiological functions and substrates are mostly unknown. Transcript expression analyses showed a predominant expression of all genes both in reproductive (female flowers, fruits, floral buds and vegetative organs (leaves, petioles. Here, we show that the recombinant poplar GSTF1 (PttGSTF1 possesses peroxidase activity towards cumene hydroperoxide and GSH-conjugation activity towards model substrates such as 2,4-dinitrochlorobenzene, benzyl and phenetyl isothiocyanate, 4-nitrophenyl butyrate and 4-hydroxy-2-nonenal but interestingly not on previously identified GSTF-class substrates. In accordance to analytical gel filtration data, crystal structure of PttGSTF1 showed a canonical dimeric organization with bound GSH or MES molecules. The structure of these protein-substrate complexes allowed delineating the residues contributing to both the G and H sites that form the active site cavity. In sum, the presence of GSTF1 transcripts and proteins in most poplar organs especially those rich in secondary metabolites such as flowers and fruits, together with its GSH-conjugation activity and its documented stress-responsive expression suggest that its function is associated with the catalytic transformation of metabolites and/or peroxide removal rather than with ligandin properties as previously reported for other GSTFs.

  5. Effect of rosemary (Rosmarinus officinalis) extracts and glutathione antioxidants on bull semen quality after cryopreservation

    Energy Technology Data Exchange (ETDEWEB)

    Daghigh-Kia, H.; Olfati-Karaji, R.; Hoseinkhani, A.; Ashrafi, I.

    2014-06-01

    The present study determined the effects of the addition of rosemary extract (ROM), glutathione (GSH), and their combination (ROM + GSH) to freezing extender on the quality of bull semen after cryopreservation. Before cryoperservation, the samples were diluted in a tris-egg yolk (TEY) extender containing 5 mM GSH (treatment I), 5 or 10 g L{sup -}1 ROM (treatments II and III), and ROM with GSH (5 mM GSH with 5 or 10 g L{sup -}1 of ROM) (treatments IV and V). An extender containing no antioxidants (non-ROM/GSH-treated) served as control group. Kinematic parameters were evaluated by means of a computer-assisted semen analysis (CASA). The viability and membrane integrity of the sperm were assessed using eosin-nigrosin stain and the hypo-osmotic swelling test (HOST) at 0 and 2 h after freezethawing. Lipooxidative parameters, superoxide dismutase, and glutathione peroxidase (GPx) activity were assessed after thawing. Treatment III showed positive effects for total motility (TM) (p < 0.01), average path velocity (VAP) (p < 0.001), viability (p < 0.01) and HOST (p < 0.01); however, lipid peroxidation (LPO) decreased (p < 0.05) and GPx activity increased (p < 0.05) immediately after thawing compared to the control. The TM (p < 0.01), VAP (p < 0.01), viability (p < 0.01), HOST (p < 0.01) decreased in LPO (p < 0.01) and GPx activity (p < 0.05) for treatment V and the viability and GPx activity (p < 0.05) for treatment I were significantly higher than for the control group at 2 h after thawing. It was concluded that the inclusion of ROM and its combination with GSH improves the post-thaw quality of bull semen. (Author)

  6. Glutathione Transferase GSTπ In Breast Tumors Evaluated By Three Techniques

    Directory of Open Access Journals (Sweden)

    Rafael Molina

    1993-01-01

    Full Text Available The glutathione transferases are involved in intracellular detoxification reactions. One of these, GSTπ, is elevated in some breast cancer cells, particularly cells selected for resistance to anticancer agents. We evaluated GSTπ expression in 60 human breast tumors by three techniques, immunohistochemistry, Northern hybridization, and Western blot analysis. There was a significant positive correlation between the three methods, with complete concordance seen in 64% of the tumors. There was strong, inverse relationship between GSTπ expression and steroid receptor status with all of the techniques utili zed. [n addition, there was a trend toward higher GSTπ expression in poorly differentiated tumors, but no correlation was found between tumor GSTπ content and DNA ploidy or %S-phase. GSTπ expression was also detected in adjacent benign breast tissue as well as infiltrating lymphocytes; this expression may contribute to GSTπ measurements using either Northern hybridization or Western blot analysis. These re sults suggest that immunohistochemistry is the method of choice for measuring GSTπ in breast tumors.

  7. Catalase and ascorbate peroxidase-representative H2O2-detoxifying heme enzymes in plants.

    Science.gov (United States)

    Anjum, Naser A; Sharma, Pallavi; Gill, Sarvajeet S; Hasanuzzaman, Mirza; Khan, Ekhlaque A; Kachhap, Kiran; Mohamed, Amal A; Thangavel, Palaniswamy; Devi, Gurumayum Devmanjuri; Vasudhevan, Palanisamy; Sofo, Adriano; Khan, Nafees A; Misra, Amarendra Narayan; Lukatkin, Alexander S; Singh, Harminder Pal; Pereira, Eduarda; Tuteja, Narendra

    2016-10-01

    Plants have to counteract unavoidable stress-caused anomalies such as oxidative stress to sustain their lives and serve heterotrophic organisms including humans. Among major enzymatic antioxidants, catalase (CAT; EC 1.11.1.6) and ascorbate peroxidase (APX; EC 1.11.1.11) are representative heme enzymes meant for metabolizing stress-provoked reactive oxygen species (ROS; such as H2O2) and controlling their potential impacts on cellular metabolism and functions. CAT mainly occurs in peroxisomes and catalyzes the dismutation reaction without requiring any reductant; whereas, APX has a higher affinity for H2O2 and utilizes ascorbate (AsA) as specific electron donor for the reduction of H2O2 into H2O in organelles including chloroplasts, cytosol, mitochondria, and peroxisomes. Literature is extensive on the glutathione-associated H2O2-metabolizing systems in plants. However, discussion is meager or scattered in the literature available on the biochemical and genomic characterization as well as techniques for the assays of CAT and APX and their modulation in plants under abiotic stresses. This paper aims (a) to introduce oxidative stress-causative factors and highlights their relationship with abiotic stresses in plants; (b) to overview structure, occurrence, and significance of CAT and APX in plants; (c) to summarize the principles of current technologies used to assay CAT and APX in plants; (d) to appraise available literature on the modulation of CAT and APX in plants under major abiotic stresses; and finally, (e) to consider a brief cross-talk on the CAT and APX, and this also highlights the aspects unexplored so far.

  8. Human glutathione S-transferase-mediated glutathione conjugation of curcumin and efflux of these conjugates in caco-2 cells

    NARCIS (Netherlands)

    Usta, M.; Wortelboer, H.M.; Vervoort, J.; Boersma, M.G.; Rietjens, I.M.C.M.; Bladeren, P.J. van; Cnubben, N.H.P.

    2007-01-01

    Curcumin, an α,β-unsaturated carbonyl compound, reacts with glutathione, leading to the formation of two monoglutathionyl curcumin conjugates. In the present study, the structures of both glutathione conjugates of curcumin were identified by LC-MS and one- and two-dimensional 1H NMR analysis, and

  9. Human glutathione S-transferase-mediated glutathione conjugation of curcumin and efflux of these conjugates in Caco-2 cells

    NARCIS (Netherlands)

    Usta, M.; Wortelboer, H.M.; Vervoort, J.J.M.; Boersma, M.G.; Rietjens, I.M.C.M.; Bladeren, van P.J.; Cnubben, N.H.P.

    2007-01-01

    Curcumin, an alpha,beta-unsaturated carbonyl compound, reacts with glutathione, leading to the formation of two monoglutathionyl curcumin conjugates. In the present study, the structures of both glutathione conjugates of curcumin were identified by LC-MS and one- and two-dimensional H-1 NMR

  10. Interactions of [alpha,beta]-unsaturated carbonyl compounds with the glutathione-related biotransformation system

    NARCIS (Netherlands)

    Iersel, van M.L.P.S.

    1998-01-01

    Introduction
    Modulation of glutathione-related biotransformation steps may play a role in important phenomena as anticarcinogenicity and multidrug resistance. Glutathione-related biotransformation comprises three main aspects i.e. glutathione, the

  11. Mn(II) regulation of lignin peroxidases and manganese-dependent peroxidases from lignin-degrading white rot fungi

    International Nuclear Information System (INIS)

    Bonnarme, P.; Jeffries, T.W.

    1990-01-01

    Two families of peroxidases-lignin peroxidase (LiP) and manganese-dependent lignin peroxidase (MnP)-are formed by the lignin-degrading white rot basidiomycete Phanerochaete chrysosporium and other white rot fungi. Isoenzymes of these enzyme families carry out reactions important to the biodegradation of lignin. This research investigated the regulation of LiP and MnP production by Mn(II). In liquid culture, LiP titers varied as an inverse function of and MnP titers varied as a direct function of the Mn(II) concentration. The extracellular isoenzyme profiles differed radically at low and high Mn(II) levels, whereas other fermentation parameters, including extracellular protein concentrations, the glucose consumption rate, and the accumulation of cell dry weight, did not change significantly with the Mn(II) concentration. In the absence of Mn(II), extracellular LiP isoenzymes predominated, whereas in the presence of Mn(II), MnP isoenzymes were dominant. The release of 14 CO 2 from 14 C-labeled dehydrogenative polymerizate lignin was likewise affected by Mn(II). The rate of 14 CO 2 release increased at low Mn(II) and decreased at high Mn(II) concentrations. This regulatory effect of Mn(II) occurred with five strains of P. chrysosporium, two other species of Phanerochaete, three species of Phlebia, Lentinula edodes, and Phellinus pini

  12. Autoradiographic detection of [125I]-secondary antiserum: a sensitive light and electron microscopic labeling method compatible with peroxidase immunocytochemistry for dual localization of neuronal antigens

    International Nuclear Information System (INIS)

    Pickel, V.M.; Chan, J.; Milner, T.A.

    1986-01-01

    We examined whether autoradiographic localization of [ 125 I]-antirabbit immunoglobulin (IgG) was suitable for light and electron microscopic detection of a rabbit antiserum to the catecholamine-synthesizing enzyme, tyrosine hydroxylase (TH), and whether autoradiographic and peroxidase labeling could be combined for simultaneous immunocytochemical identification of TH and neuropeptides in brain. Adult rat brains were fixed by aortic arch perfusion with acrolein and paraformaldehyde. Vibratome sections of the fixed tissues were incubated with various dilutions of TH antiserum followed by [ 125 I]-secondary IgG. These sections were then directly processed for autoradiography or were incubated with rabbit antiserum to substance P (SP) or methionine [Met5]-enkephalin (ME). These latter sections were then processed by the peroxidase-antiperoxidase (PAP) or conjugated peroxidase methods followed by autoradiography. Exposure periods of 12-20 days for light microscopy or 90 days for electron microscopy yielded substantial accumulations of silver grains even at the highest (1:30,000) dilution of TH antiserum. At this dilution, immunoreactivity for TH was virtually nondetectable by PAP and conjugated peroxidase methods. The differential sensitivities of the autoradiographic versus peroxidase methods provided a means for separable identification of rabbit antiserum to TH and to SP or ME. Ultrastructural analysis of the catecholaminergic neurons in the medial nuclei of the solitary tract (NTS) showed selective cytoplasmic localization of silver grains for [ 125 I]-labeling of TH in perikarya, dendrites, and terminals. Within single thin sections prepared for dual labeling, the peroxidase marker for SP and for ME was differentially localized with respect to autoradiographic labeling of TH

  13. Biological therapy of strontium-substituted bioglass for soft tissue wound-healing: responses to oxidative stress in ovariectomised rats.

    Science.gov (United States)

    Jebahi, S; Oudadesse, H; Jardak, N; Khayat, I; Keskes, H; Khabir, A; Rebai, T; El Feki, H; El Feki, A

    2013-07-01

    New synthetic biomaterials are constantly being developed for wound repair and regeneration. Bioactive glasses (BG) containing strontium have shown successful applications in tissue engineering account of their biocompatibility and the positive biological effects after implantation. This study aimed to assess whether BG-Sr was accepted by the host tissue and to characterize oxidative stress biomarker and antioxidant enzyme profiles during muscle and skin healing. Wistar rats were divided into five groups (six animals per group): the group (I) was used as negative control (T), after ovariectomy, groups II, III, IV and V were used respectively as positive control (OVX), implanted tissue with BG (OVX-BG), BG-Sr (OVX-BG-Sr) and presented empty defects (OVX-NI). Soft tissues surrounding biomaterials were used to estimate superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx) and malondialdehyde (MDA) concentration. Our results show that 60 days after operation, treatment of rats with BG-Sr significantly increased MDA concentration and caused an increase of SOD, CAT and GPx activities in both skin and muscular tissues. BG-Sr revealed maturation of myotubes followed a normal appearance of muscle regenerated with high density and mature capillary vessels. High wound recovery with complete re-epithelialization and regeneration of skin was observed. The results demonstrate that the protective action against reactive oxygen species (ROS) was clearly observed in soft tissue surrounding BG-Sr. Moreover, the potential use of BG-Sr rapidly restores the wound skin and muscle structural and functional properties. The BG advantages such as ion release might make BG-Sr an effective biomaterial choice for antioxidative activity. Copyright © 2013 Elsevier Masson SAS. All rights reserved.

  14. Preventive effects of garlic (Allium sativum) on oxidative stress and histopathology of cardiac tissue in streptozotocin-induced diabetic rats.

    Science.gov (United States)

    Naderi, R; Mohaddes, G; Mohammadi, M; Alihemmati, A; Badalzadeh, R; Ghaznavi, R; Ghyasi, R; Mohammadi, Sh

    2015-12-01

    Since some complications of diabetes mellitus may be caused or exacerbated by an oxidative stress, the protective effects of garlic (Allium sativum) were investigated in the blood and heart of streptozotocin-induced diabetic rats. Twenty-eight male Wistar rats were randomly divided into four groups: control, garlic, diabetic, and diabetic+garlic. Diabetes was induced by intraperitoneal (i.p.) injection of streptozotocin (50 mg/kg) in male rats. Rats were fed with raw fresh garlic homogenate (250 mg/kg) six days a week by gavage for a period of 6 weeks. At the end of the 6th week blood samples and heart tissues were collected and used for determination of glutathione peroxidase (GPx), superoxide dismutase (SOD), catalase (CAT), malondialdehyde (MDA) and histological evaluation. Induction of diabetes increased MDA levels in blood and homogenates of heart. In diabetic rats treated with garlic, MDA levels decreased in blood and heart homogenates. Treatment of diabetic rats with garlic increased SOD, GPX and CAT in blood and heart homogenates. Histopathological finding of the myocardial tissue confirmed a protective role for garlic in diabetic rats. Thus, the present study reveals that garlic may effectively modulate antioxidants status in the blood and heart of streptozotocin induced-diabetic rats.

  15. A new role for glutathione in the regulation of root architecture linked to strigolactones.

    Science.gov (United States)

    Marquez-Garcia, Belen; Njo, Maria; Beeckman, Tom; Goormachtig, Sofie; Foyer, Christine H

    2014-02-01

    Reduced glutathione (GSH) is required for root development, but its functions are not characterized. The effects of GSH depletion on root development were therefore studied in relation to auxin and strigolactone (SL) signalling using a combination of molecular genetic approaches and pharmacological techniques. Lateral root (LR) density was significantly decreased in GSH synthesis mutants (cad2-1, pad2-, rax1-), but not by the GSH synthesis inhibitor, buthionine sulfoximine (BSO). BSO-induced GSH depletion therefore did not influence root architecture in the same way as genetic impairment. Root glutathione contents were similar in the wild-type seedlings and max3-9 and max4-1 mutants that are deficient in SL synthesis and in the SL-signalling mutant, max2-1. BSO-dependent inhibition of GSH synthesis depleted the tissue GSH pool to a similar extent in the wild-type and SL synthesis mutants, with no effect on LR density. The application of the SL analogue GR24 increased root glutathione in the wild-type, max3-9 and max4-1 seedlings, but this increase was absent from max2-1. Taken together, these data establish a link between SLs and the GSH pool that occurs in a MAX2-dependent manner. © 2013 John Wiley & Sons Ltd.

  16. Glutathione S - transferases class Pi and Mi and their significance in oncology

    Directory of Open Access Journals (Sweden)

    Zofia Marchewka

    2017-06-01

    Full Text Available In this article the current data, which shows that glutathione S-transferases (GST class Pi and Mi are interesting and promising biomarkers in acute and chronic inflammatory processes as well as in the oncology, were presented based on the review of the latest experimental and clinical studies. The article shows their characteristics, functions and participation (direct - GST Pi, indirect - GST Mi in the regulation of signaling pathways of JNK kinases, which are involved in cell differentiation. Overexpression of glutathione S-transferases class Pi and Mi in many cancer cells plays a key role in cancer treatment, making them resistant to chemotherapy. GST isoenzymes are involved in the metabolism of various types of xenobiotics and endogenous substrates, so their altered expression in cancer tissues as well as in serum and urine could be an important potential marker of the cancer and an indicator of oxidative stress. The study shows the role of glutathione S-transferases in redox homeostasis of tumor cells and in the mechanism of resistance to anticancer drugs.

  17. Glutathione S - transferases class Pi and Mi and their significance in oncology.

    Science.gov (United States)

    Marchewka, Zofia; Piwowar, Agnieszka; Ruzik, Sylwia; Długosz, Anna

    2017-06-19

    In this article the current data, which shows that glutathione S-transferases (GST) class Pi and Mi are interesting and promising biomarkers in acute and chronic inflammatory processes as well as in the oncology, were presented based on the review of the latest experimental and clinical studies. The article shows their characteristics, functions and participation (direct - GST Pi, indirect - GST Mi) in the regulation of signaling pathways of JNK kinases, which are involved in cell differentiation. Overexpression of glutathione S-transferases class Pi and Mi in many cancer cells plays a key role in cancer treatment, making them resistant to chemotherapy. GST isoenzymes are involved in the metabolism of various types of xenobiotics and endogenous substrates, so their altered expression in cancer tissues as well as in serum and urine could be an important potential marker of the cancer and an indicator of oxidative stress. The study shows the role of glutathione S-transferases in redox homeostasis of tumor cells and in the mechanism of resistance to anticancer drugs.

  18. Nucleation behavior of glutathione polymorphs in water

    International Nuclear Information System (INIS)

    Chen, Zhi; Dang, Leping; Li, Shuai; Wei, Hongyuan

    2013-01-01

    Nucleation behavior of glutathione (GSH) polymorphs in water was investigated by experimental method combined with classical nucleation theory. The solubility of α and β forms GSH in water at different temperatures, and the nucleation induction period at various supersaturations and temperatures were determined experimentally. The results show that, in a certain range of supersaturation, the nucleation of β form predominates at relatively higher temperature, while α form will be obtained at lower temperature. The nucleation kinetics parameters of α and β form were then calculated. To understand the crucial role of temperature on crystal forms, “hypothetic” nucleation parameters of β form at 283.15 K were deduced based on extrapolation method. The results show that the interfacial tension, critical free energy, critical nucleus radius and nucleus number of α form are smaller than that of β form in the same condition at 283.15 K, which implies that α form nucleates easier than β form at low temperature. This work may be useful for the control and optimization of GSH crystallization process in industry

  19. Labor Augmentation with Oxytocin Decreases Glutathione Level

    Directory of Open Access Journals (Sweden)

    Naomi Schneid-Kofman

    2009-01-01

    Full Text Available Objective. To compare oxidative stress following spontaneous vaginal delivery with that induced by Oxytocin augmented delivery. Methods. 98 women recruited prior to labor. 57 delivered spontaneously, while 41 received Oxytocin for augmentation of labor. Complicated deliveries and high-risk pregnancies were excluded. Informed consent was documented. Arterial cord blood gases, levels of Hematocrit, Hemoglobin, and Bilirubin were studied. Glutathione (GSH concentration was measured by a spectroscopic method. Plasma and red blood cell (RBC levels of Malondialdehyde indicated lipid peroxidation. RBC uptake of phenol red denoted cell penetrability. SPSS data analysis was used. Results. Cord blood GSH was significantly lower in the Oxytocin group (2.3±0.55 mM versus 2.55±0.55 mM, =.01. No differences were found in plasma or RBC levels of MDA or in uptake of Phenol red between the groups. Conclusion. Lower GSH levels following Oxytocin augmentation indicate an oxidative stress, though selected measures of oxidative stress demonstrate no cell damage.

  20. Role of glutathione redox cycle and catalase in defense against oxidative stress induced by endosulfan in adrenocortical cells of rainbow trout (Oncorhynchus mykiss)

    International Nuclear Information System (INIS)

    Dorval, J.; Hontela, A.

    2003-01-01

    The role of antioxidants in maintaining the functional integrity of adrenocortical cells during in vitro exposure to endosulfan, an organochlorine pesticide, was investigated in rainbow trout (Oncorhynchus mykiss). Aminotriazole (ATA), an inhibitor of catalase (CAT), L-buthionine sulfoximine (L-BSO), an inhibitor of glutathione (GSH) synthesis, and N-acetyl cysteine (NAC), a glutathione precursor, were used to investigate the role of CAT and GSH redox cycle in protection against the adrenal toxicity of endosulfan, a pesticide that impairs cell viability (LC 50 366 μM) and cortisol secretion (EC 50 19 μM) in a concentration-related manner. Pretreatment with ATA and L-BSO enhanced the toxicity of endosulfan (LC 50 and EC 50 , respectively, 302 and 2.6 μM with ATA, 346 and 3.1 μM with L-BSO), while pretreatment with NAC had no significant effect on cell viability and increased the EC 50 of endosulfan to 51 μM. CAT activity was significantly reduced following exposure to endosulfan when cells were pretreated with ATA. Pretreatment with L-BSO significantly decreased glutathione peroxidase (GPx) activity and reduced glutathione (GSH) levels in a concentration-related manner following exposure to endosulfan, while GSH levels were significantly higher in NAC pretreated cells compared to untreated cells. Finally, pretreatment with ATA and L-BSO increased, while pretreatment with NAC decreased, lipid hydroperoxides (LOOH) levels. CAT, GPx, and GSH were identified as important antioxidants in maintaining the function and integrity of rainbow trout adrenocortical cells and ATA, L-BSO, and NAC were identified as effective modulators of CAT and GSH redox cycle. Moreover, this study suggests that the glutathione redox cycle may be more efficient than catalase in protecting adrenocortical cells against endosulfan-induced oxidative stress

  1. Thiol-Disulfide Exchange between Glutaredoxin and Glutathione

    DEFF Research Database (Denmark)

    Iversen, Rasmus; Andersen, Peter Anders; Jensen, Kristine Steen

    2010-01-01

    Glutaredoxins are ubiquitous thiol-disulfide oxidoreductases which catalyze the reduction of glutathione-protein mixed disulfides. Belonging to the thioredoxin family, they contain a conserved active site CXXC motif. The N-proximal active site cysteine can form a mixed disulfide with glutathione ...... has been replaced with serine. The exchange reaction between the reduced protein and oxidized glutathione leading to formation of the mixed disulfide could readily be monitored by isothermal titration calorimetry (ITC) due to the enthalpic contributions from the noncovalent interactions...

  2. Effect of glutathione depletion on the aerobic radiation response of A549 human lung carcinoma cells

    International Nuclear Information System (INIS)

    Biaglow, J.E.; Clark, E.P.; Varnes, M.E.; Tuttle, S.W.; Epp, E.R.

    1985-01-01

    The authors demonstrated that depletion of glutathione (GSH) from cultured A549 cells to non-detectable levels, using L-buthionine sulfoximine (L-BSO), results in an increased aerobic radiation response. This response can be further increased if dimethylfumarate (DMF) is added concurrently with L-BSO. L-BSO is a relatively slow depletor of GSH compared to DMF, which acts by both spontaneous and enzyme catalysed reactions. The authors have studied: 1. the effect of continuous long-term exposure to 0.1 mM L-BSO on GSH levels and the subsequent radiation response and 2. the effect of GSH depletion on enzymes essential for radical detoxification. The results show an enhanced aerobic radiation response that increases with the time of exposure to L-BSO. For example surviving fraction (S.F.) after 5 Gy for cells exposed to L-BSO for 24 hrs is 0.004 and 0.08 for control cultures. Cells washed free of medium and irradiated in Hanks' show 0.0007 S.F. after 120 hr exposure to L-BSO and S.F. of 0.075 for the control cultures. The relationship between the chronic GSH depleted state, GSH peroxidase, and radiation induced lipid peroxidation is being investigated

  3. Alleviation of isoproturon toxicity to wheat by exogenous application of glutathione.

    Science.gov (United States)

    Nemat Alla, Mamdouh M; Hassan, Nemat M

    2014-06-01

    Treatment with the recommended field dose of isoproturon to 7-d-old wheat seedlings significantly decreased shoot height, fresh and dry weights during the subsequent 15days. Meanwhile contents of carotenoids, chlorophylls and anthocyanin as well as activities of δ-aminolevulinate dehydratase (ALA-D), phenylalanine ammonia lyase (PAL) and tyrosine ammonia lyase (TAL) were significantly inhibited. On the other hand, the herbicide significantly increased malondialdehyde (MDA), a naturally occurring product of lipid peroxidation and H2O2, while it significantly decreased the contents of glutathione (GSH) and ascorbic acid (AsA) and reduced the activities of superoxide dismutase (SOD), catalase (CAT) and ascorbate peroxidase (APX). These findings indicate an induction of a stress status in wheat seedlings following isoproturon treatment. However, exogenous GSH appeared to limit the toxic effects of isoproturon and seemed to overcome this stress status. Most likely, contents of pigment and activities of enzymes were raised to approximate control levels. Moreover, antioxidants were elevated and the oxidative stress indices seemed to be alleviated by GSH application. These results indicate that exogenous GSH enhances enzymatic and nonenzymatic antioxidants to alleviate the effects of isoproturon. Copyright © 2014 Elsevier Inc. All rights reserved.

  4. Hydroxytyrosol prevents reduction in liver activity of Δ-5 and Δ-6 desaturases, oxidative stress, and depletion in long chain polyunsaturated fatty acid content in different tissues of high-fat diet fed mice.

    Science.gov (United States)

    Valenzuela, Rodrigo; Echeverria, Francisca; Ortiz, Macarena; Rincón-Cervera, Miguel Ángel; Espinosa, Alejandra; Hernandez-Rodas, María Catalina; Illesca, Paola; Valenzuela, Alfonso; Videla, Luis A

    2017-04-11

    Eicosapentaenoic acid (EPA, C20:5n-3), docosahexaenoic acid (DHA, C22:6n-3) and arachidonic acid (AA, C20:4n-6) are long-chain polyunsaturated fatty acids (LCPUFAs) with relevant roles in the organism. EPA and DHA are synthesized from the precursor alpha-linolenic acid (ALA, C18:3n-3), whereas AA is produced from linoleic acid (LA, C18:2n-6) through the action of Δ5 and Δ6-desaturases. High-fat diet (HFD) decreases the activity of both desaturases and LCPUFA accretion in liver and other tissues. Hydroxytyrosol (HT), a natural antioxidant, has an important cytoprotective effects in different cells and tissues. Male mice C57BL/6 J were fed a control diet (CD) (10% fat, 20% protein, 70% carbohydrates) or a HFD (60% fat, 20% protein, 20% carbohydrates) for 12 weeks. Animals were daily supplemented with saline (CD) or 5 mg HT (HFD), and blood and the studied tissues were analyzed after the HT intervention. Parameters studied included liver histology (optical microscopy), activity of hepatic desaturases 5 and 6 (gas-liquid chromatography of methyl esters derivatives) and antioxidant enzymes (catalase, superoxide dismutase, glutathione peroxidase, and glutathione reductase by spectrophotometry), oxidative stress indicators (glutathione, thiobarbituric acid reactants, and the antioxidant capacity of plasma), gene expression assays for sterol regulatory element-binding protein 1c (SREBP-1c) (qPCR and ELISA), and LCPUFA profiles in liver, erythrocyte, brain, heart, and testicle (gas-liquid chromatography). HFD led to insulin resistance and liver steatosis associated with SREBP-1c upregulation, with enhancement in plasma and liver oxidative stress status and diminution in the synthesis and storage of n-6 and n-3 LCPUFAs in the studied tissues, compared to animals given control diet. HT supplementation significantly reduced fat accumulation in liver and plasma as well as tissue metabolic alterations induced by HFD. Furthermore, a normalization of desaturase activities

  5. The gut microbiota modulates host amino acid and glutathione metabolism in mice

    DEFF Research Database (Denmark)

    Mardinoglu, Adil; Shoaie, Saeed; Bergentall, Mattias

    2015-01-01

    , liver, and adipose tissues. We used these functional models to determine the global metabolic differences between CONV-R and GF mice. Based on gene expression data, we found that the gut microbiota affects the host amino acid (AA) metabolism, which leads to modifications in glutathione metabolism...... conventionally raised (CONV-R) and germ-free (GF) mice using gene expression data and tissue-specific genome-scale metabolic models (GEMs). We created a generic mouse metabolic reaction (MMR) GEM, reconstructed 28 tissue-specific GEMs based on proteomics data, and manually curated GEMs for small intestine, colon....... To validate our predictions, we measured the level of AAs and N-acetylated AAs in the hepatic portal vein of CONV-R and GF mice. Finally, we simulated the metabolic differences between the small intestine of the CONV-R and GF mice accounting for the content of the diet and relative gene expression differences...

  6. Demonstration of Lignin-to-Peroxidase Direct Electron Transfer

    Science.gov (United States)

    Sáez-Jiménez, Verónica; Baratto, Maria Camilla; Pogni, Rebecca; Rencoret, Jorge; Gutiérrez, Ana; Santos, José Ignacio; Martínez, Angel T.; Ruiz-Dueñas, Francisco Javier

    2015-01-01

    Versatile peroxidase (VP) is a high redox-potential peroxidase of biotechnological interest that is able to oxidize phenolic and non-phenolic aromatics, Mn2+, and different dyes. The ability of VP from Pleurotus eryngii to oxidize water-soluble lignins (softwood and hardwood lignosulfonates) is demonstrated here by a combination of directed mutagenesis and spectroscopic techniques, among others. In addition, direct electron transfer between the peroxidase and the lignin macromolecule was kinetically characterized using stopped-flow spectrophotometry. VP variants were used to show that this reaction strongly depends on the presence of a solvent-exposed tryptophan residue (Trp-164). Moreover, the tryptophanyl radical detected by EPR spectroscopy of H2O2-activated VP (being absent from the W164S variant) was identified as catalytically active because it was reduced during lignosulfonate oxidation, resulting in the appearance of a lignin radical. The decrease of lignin fluorescence (excitation at 355 nm/emission at 400 nm) during VP treatment under steady-state conditions was accompanied by a decrease of the lignin (aromatic nuclei and side chains) signals in one-dimensional and two-dimensional NMR spectra, confirming the ligninolytic capabilities of the enzyme. Simultaneously, size-exclusion chromatography showed an increase of the molecular mass of the modified residual lignin, especially for the (low molecular mass) hardwood lignosulfonate, revealing that the oxidation products tend to recondense during the VP treatment. Finally, mutagenesis of selected residues neighboring Trp-164 resulted in improved apparent second-order rate constants for lignosulfonate reactions, revealing that changes in its protein environment (modifying the net negative charge and/or substrate accessibility/binding) can modulate the reactivity of the catalytic tryptophan. PMID:26240145

  7. Chronic effects of dichloromethane on amino acids, glutathione and phosphoethanolamine in gerbil brain

    Energy Technology Data Exchange (ETDEWEB)

    Briving, C.; Hamberger, A.; Kjellstrand, P.; Rosengren, L.; Karlsson, J.E.; Haglid, K.G.

    1986-06-01

    Mongolian gerbils were exposed to dichloromethane for three months by continuous inhalation at 210 ppm. Total free tissue amino acids, glutathione, and phosphoethanolamine were determined in the vermis posterior of the cerebellum and the frontal cerebral cortex. These two brain areas were chosen because humans occupationally exposed to dichloromethane have shown abnormalities in the electroencephalogram of the frontal part of the cerebral cortex. This study showed that long-term exposure of gerbils to dichloromethane (210 ppm) for three months leads to decreased levels of glutamate, gamma-aminobutyric acid, and phosphoethanolamine in the frontal cerebral cortex, while glutamine and gamma-aminobutyric acid are elevated in the posterior cerebellar vermis.

  8. Glutathione depletion prevents diet-induced obesity and enhances insulin sensitivity.

    Science.gov (United States)

    Findeisen, Hannes M; Gizard, Florence; Zhao, Yue; Qing, Hua; Jones, Karrie L; Cohn, Dianne; Heywood, Elizabeth B; Bruemmer, Dennis

    2011-12-01

    Excessive accumulation of reactive oxygen species (ROS) in adipose tissue has been implicated in the development of insulin resistance and type 2 diabetes. However, emerging evidence suggests a physiologic role of ROS in cellular signaling and insulin sensitivity. In this study, we demonstrate that pharmacologic depletion of the antioxidant glutathione in mice prevents diet-induced obesity, increases energy expenditure and locomotor activity, and enhances insulin sensitivity. These observations support a beneficial role of ROS in glucose homeostasis and warrant further research to define the regulation of metabolism and energy balance by ROS.

  9. Glutathione-induced drought stress tolerance in mung bean: coordinated roles of the antioxidant defence and methylglyoxal detoxification systems

    Science.gov (United States)

    Nahar, Kamrun; Hasanuzzaman, Mirza; Alam, Md. Mahabub; Fujita, Masayuki

    2015-01-01

    Drought is considered one of the most acute environmental stresses presently affecting agriculture. We studied the role of exogenous glutathione (GSH) in conferring drought stress tolerance in mung bean (Vigna radiata L. cv. Binamoog-1) seedlings by examining the antioxidant defence and methylglyoxal (MG) detoxification systems and physiological features. Six-day-old seedlings were exposed to drought stress (−0.7 MPa), induced by polyethylene glycol alone and in combination with GSH (1 mM) for 24 and 48 h. Drought stress decreased seedling dry weight and leaf area; resulted in oxidative stress as evidenced by histochemical detection of hydrogen peroxide (H2O2) and O2⋅− in the leaves; increased lipid peroxidation (malondialdehyde), reactive oxygen species like H2O2 content and O2⋅− generation rate and lipoxygenase activity; and increased the MG level. Drought decreased leaf succulence, leaf chlorophyll and relative water content (RWC); increased proline (Pro); decreased ascorbate (AsA); increased endogenous GSH and glutathione disulfide (GSSG) content; decreased the GSH/GSSG ratio; increased ascorbate peroxidase and glutathione S-transferase activities; and decreased the activities of monodehydroascorbate reductase (MDHAR), dehydroascorbate reductase (DHAR) and catalase. The activities of glyoxalase I (Gly I) and glyoxalase II (Gly II) increased due to drought stress. In contrast to drought stress alone, exogenous GSH enhanced most of the components of the antioxidant and glyoxalase systems in drought-affected mung bean seedlings at 24 h, but GSH did not significantly affect AsA, Pro, RWC, leaf succulence and the activities of Gly I and DHAR after 48 h of stress. Thus, exogenous GSH supplementation with drought significantly enhanced the antioxidant components and successively reduced oxidative damage, and GSH up-regulated the glyoxalase system and reduced MG toxicity, which played a significant role in improving the physiological features and drought

  10. Shikonin protects dopaminergic cell line PC12 against 6-hydroxydopamine-mediated neurotoxicity via both glutathione-dependent and independent pathways and by inhibiting apoptosis.

    Science.gov (United States)

    Esmaeilzadeh, Emran; Gardaneh, Mossa; Gharib, Ehsan; Sabouni, Farzaneh

    2013-08-01

    We have investigated the mechanism of shikonin function on protection of dopaminergic neurons against 6-OHDA-induced neurotoxicity. Treatment of rat pheochromocytoma cell line PC12 by serial dilutions of shikonin determined 10 μM of the compound as its optimum concentration for protection saving nearly 70 % of the cells against toxicity. Reverse transcription-PCR analysis of shikonin-treated cells showed threefold increase in mRNA levels of glutathione peroxidase-1 (GPX-1) as a representative component of the intracellular anti-oxidant defense system. To elucidate shikonin-GPX1 relationships and maximize protection, we transduced PC12 cells using recombinant lentivirus vectors that harbored GPX-1 coding sequence. This change upregulated GPX-1 expression, increased peroxidase activity and made neuronal cells resistant to 6-OHDA-mediated toxicity. More importantly, addition of shikonin to GPX1-overexpressing PC12 cells augmented GPX-1 protein content by eightfold leading to fivefold increase of enzymatic activity, 91 % cell survival against neurotoxicity and concomitant increases in intracellular glutathione (GSH) levels. Depletion of intracellular GSH rendered all cell groups highly susceptible to toxicity; however, shikonin was capable of partially saving them. Subsequently, GSH-independent superoxide dismutase mRNA was found upregulated by shikonin. As signs of apoptosis inhibition, the compound upregulated Bcl-2, downregulated Bax, and prevented cell nuclei from undergoing morphological changes typical of apoptosis. Also, a co-staining method demonstrated GPX-1 overexpression significantly increases the percent of live cells that is maximized by shikonin treatment. Our data indicate that shikonin as an antioxidant compound protects dopaminergic neurons against 6-OHDA toxicity and enhances their survival via both glutathione-dependent and direct anti-apoptotic pathways.

  11. Hemoglobin-catalyzed fluorometric method for the determination of glutathione

    Science.gov (United States)

    Wang, Ruiqiang; Tang, Lin; Li, Hua; Wang, Yi; Gou, Rong; Guo, Yuanyuan; Fang, Yudong; Chen, Fengmei

    2016-01-01

    A new spectrofluorometric method for the determination of glutathione based on the reaction catalyzed by hemoglobin was reported. The reaction product gave a highly fluorescent intensity with the excitation and emission wavelengths of 320.0 nm and 413.0 nm, respectively. The optimum experimental conditions were investigated. Results showed that low concentration glutathione enhanced the fluorescence intensity significantly. The line ranges were 1.0 × 10-6-1.0 × 10-5 mol L-1 of glutathione and 6.0 × 10-10 mol L-1-1.0 × 10-8 mol L-1, respectively. The detection limit was calculated to be 1.1 × 10-11 mol L-1. The recovery test by the standard addition method gave values in the range of 90.78%-102.20%. This method was used for the determination of glutathione in synthetic and real samples with satisfactory results.

  12. Oxidative Stress Markers and Genetic Polymorphisms of Glutathione ...

    African Journals Online (AJOL)

    2017-10-26

    Oct 26, 2017 ... stress such as asthma, lung cancer, and type 2 diabetes mellitus.[11-13]. Although ... epigenetic, and environmental factors. Little is known ..... glutathione Stransferase genes increase risk of prostate cancer biochemical ...

  13. Glutathione transferase mimics : Micellar catalysis of an enzymic reaction

    NARCIS (Netherlands)

    Lindkvist, Björn; Weinander, Rolf; Engman, Lars; Koetse, Marc; Engberts, Jan B.F.N.; Morgenstern, Ralf

    1997-01-01

    Substances that mimic the enzyme action of glutathione transferases (which serve in detoxification) are described. These micellar catalysts enhance the reaction rate between thiols and activated halogenated nitroarenes as well as alpha,beta-unsaturated carbonyls. The nucleophilic aromatic

  14. Electrolyte ions and glutathione enzymes as stress markers in ...

    African Journals Online (AJOL)

    Electrolyte ions and glutathione enzymes as stress markers in Argania spinosa subjected to drought stress and recovery. ... By Country · List All Titles · Free To Read Titles This Journal is Open Access. Featuring journals from 32 Countries:.

  15. Inhibition of glutathione S-transferases (GSTs) activity from cowpea ...

    African Journals Online (AJOL)

    STORAGESEVER

    2009-10-19

    Oct 19, 2009 ... Inhibition effect of the plant extracts on the GST was studied by spectrophotometric method. The ... of assuring food security in developing countries like ..... studies on African cat fish (Clarias gariepinus) liver glutathione s-.

  16. Protective effect of gel form of gastric gavage applicated aloe vera on ischemia reperfusion injury in renal and lung tissue.

    Science.gov (United States)

    Sahin, Hasan; Yener, Ali Umit; Karaboga, Ihsan; Sehitoglu, Muserref Hilal; Dogu, Tugba; Altinisik, Hatice Betul; Altinisik, Ugur; Simsek, Tuncer

    2017-12-30

    The aloe vera plant has become increasingly popular in recent years. This study aimed to research the effect of aloe vera to prevent renal and lung tissue damage in an experimental ischemia-reperfusion (I/R) injury model. The study included 21 male Wistar Albino rats, which were categorized into control group, n = 7 (no procedures), Sham group n = 7 (I/R); and aloe vera therapy group, n = 7 (aloe vera and I/R). Superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx), and malondialdehyde (MDA) were evaluated from lung and kidney tissues for biochemical investigations. As histopathological, hematoxylin and eosin and anti-iNOS were also examined. In biochemical investigations, SOD, CAT, and GPx levels of the Sham group were found to be lower compared with the other groups (P < 0.05). The aloe vera therapy group was not statistically different from control groups but significantly different compared with the Sham group. In the same way, the MDA levels of kidney and lung tissues were statistically significant in the aloe vera therapy group, compared to the Sham group. In the Sham group, the peribronchial and perialveolar edema were observed in lung parenchyma. Also, excess interstitial hemorrhage, leukocyte infiltration, and alveolar wall thickening were identified in ischemic groups. The histopathological changes were much lighter than in the aloe vera therapy group. In renal tissues, excess epithelial cell deterioration, tubular desqumination, and glomerular atrophy were observed in the Sham group. The histopathological changes were markedly reduced in the aloe vera therapy  group. In the kidney and lung tissue, the level of iNOS activity in the Sham group was significantly higher than in the control and aloe vera therapy group. This study indicated that aloe vera is protective against oxidative damage formed by I/R in distant organs like the lungs and kidneys.

  17. Fluorescence detection of glutathione and oxidized glutathione in blood with a NIR-excitable cyanine probe

    Science.gov (United States)

    Liu, Chang-hui; Qi, Feng-pei; Wen, Fu-bin; Long, Li-ping; Liu, Ai-juan; Yang, Rong-hua

    2018-04-01

    Cyanine has been widely utilized as a near infrared (NIR) fluorophore for detection of glutathione (GSH). However, the excitation of most of the reported cyanine-based probes was less than 800 nm, which inevitably induce biological background absorption and lower the sensitivity, limiting their use for detection of GSH in blood samples. To address this issue, here, a heptamethine cyanine probe (DNIR), with a NIR excitation wavelength at 804 nm and a NIR emission wavelength at 832 nm, is employed for the detection of GSH and its oxidized form (GSSG) in blood. The probe displays excellent selectivity for GSH over GSSG and other amino acids, and rapid response to GSH, in particular a good property for indirect detection of GSSG in the presence of enzyme glutathione reductase and the reducing agent nicotinamideadenine dinucleotide phosphate, without further separation prior to fluorescent measurement. To the best of our knowledge, this is the first attempt to explore NIR fluorescent approach for the simultaneous assay of GSH and GSSG in blood. As such, we expect that our fluorescence sensors with both NIR excitation and NIR emission make this strategy suitable for the application in complex physiological systems.

  18. Intracellular thiol levels and radioresistance: Studies with glutathione and glutathione mono ethyl ester

    International Nuclear Information System (INIS)

    Astor, M.B.; Meister, A.; Anderson, M.E.

    1987-01-01

    Intracellular thiols such as glutathione (GSH) protect cells against free radicals formed during oxidative metabolism or from exposure to drugs or ionizing radiation. The role of intracellular GSH in the repair of radiation induced free radical damage was studied using GSH or its analog glutathione mono ethyl ester (GEE), which readily penetrates into the cell. Chinese hamster V79 cells with normal GSH levels were afforded equal protection under aerated and hypoxic conditions (DMF = 1.2 OER = 3.7) by both 10 mM GSH and GEE although GEE had raised interacellular GSH levels three-fold. Growth of V79 cells in cysteine free media resulted in undetectable levels of GSH and OER of 2.2 with no change in aerated survival. Restoration of intracellular GSH by 10 mM GEE resulted in an increase of the OER from 2.2. to 3.8 (DMF = 1.7). Only 14% of the intracellular GSH needs to be repleted to give an OER of 3.0. These experiments provide evidence that thiols do play a role in the oxygen effect and are present at levels in excess of what is necessary for maximal radioprotection

  19. Reduced glutathione and glutathione disulfide in the blood of glucose-6-phosphate dehydrogenase-deficient newborns.

    Science.gov (United States)

    Gong, Zhen-Hua; Tian, Guo-Li; Huang, Qi-Wei; Wang, Yan-Min; Xu, Hong-Ping

    2017-07-20

    Glucose-6-phosphate dehydrogenase (G6PD) deficiency is commonly detected during mass screening for neonatal disease. We developed a method to measure reduced glutathione (GSH) and glutathione disulfide (GSSG) using tandem mass spectrometry (MS/MS) for detecting G6PD deficiency. The concentration of GSH and the GSH/GSSG ratio in newborn dry-blood-spot (DBS) screening and in blood plus sodium citrate for test confirmation were examined by MS/MS using labeled glycine as an internal standard. G6PD-deficient newborns had a lower GSH content (242.9 ± 15.9 μmol/L)and GSH/GSSG ratio (14.9 ± 7.2) than neonatal controls (370.0 ± 53.2 μmol/L and 46.7 ± 19.6, respectively). Although the results showed a significance of P blood measured using MS/MS on the first day of sample preparation are consistent with G6PD activity and are helpful for diagnosing G6PD deficiency.

  20. Subcellular distribution of glutathione and cysteine in cyanobacteria

    OpenAIRE

    Zechmann, Bernd; Tomašić, Ana; Horvat, Lucija; Fulgosi, Hrvoje

    2010-01-01

    Glutathione plays numerous important functions in eukaryotic and prokaryotic cells. Whereas it can be found in virtually all eukaryotic cells, its production in prokaryotes is restricted to cyanobacteria and proteobacteria and a few strains of gram-positive bacteria. In bacteria, it is involved in the protection against reactive oxygen species (ROS), osmotic shock, acidic conditions, toxic chemicals, and heavy metals. Glutathione synthesis in bacteria takes place in two steps out of cysteine,...

  1. Cu–hemin metal-organic frameworks with peroxidase-like activity as peroxidase mimics for colorimetric sensing of glucose

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Fenfen; He, Juan; Zeng, Mulang; Hao, Juan; Guo, Qiaohui; Song, Yonghai; Wang, Li, E-mail: lwanggroup@aliyun.com [Jiangxi Normal University, Key Laboratory of Functional Small Organic Molecule, Ministry of Education, College of Chemistry and Chemical Engineering (China)

    2016-05-15

    In this work, a facile strategy to synthesize Cu–hemin metal-organic frameworks (MOFs) with peroxidase-like activity was reported. The prepared Cu–hemin MOFs were characterized by various techniques such as scanning electron microscopy, transmission electron microscopy, X-ray powder diffraction, Fourier transform infrared spectroscopy, UV–visible absorbance spectra, and so on. The results showed that the prepared Cu–hemin MOFs looked like a ball-flower with an average diameter of 10 μm and provided a large specific surface area. The Cu–hemin MOFs possessing peroxidase-like activity could be used to catalyze the peroxidase substrate of 3,3,5,5-tetramethylbenzidine in the presence of H{sub 2}O{sub 2}, which was employed to detect H{sub 2}O{sub 2} quantitatively with the linear range from 1.0 μM to 1.0 mM and the detection limit was 0.42 μM. Furthermore, with the additional help of glucose oxidase, a sensitive and selective method to detect glucose was developed by using the Cu–hemin MOFs as catalyst and the linear range was from 10.0 μM to 3.0 mM and the detection limit was 6.9 μM. This work informs researchers of the advantages of MOFs for preparing biomimetic catalysts and extends the functionality of MOFs for biosensor application.Graphical Abstract.

  2. Hierarchical hybrid peroxidase catalysts for remediation of phenol wastewater

    KAUST Repository

    Duan, Xiaonan

    2014-02-20

    We report a new family of hierarchical hybrid catalysts comprised of horseradish peroxidase (HRP)-magnetic nanoparticles for advanced oxidation processes and demonstrate their utility in the removal of phenol from water. The immobilized HRP catalyzes the oxidation of phenols in the presence of H2O2, producing free radicals. The phenoxy radicals react with each other in a non-enzymatic process to form polymers, which can be removed by precipitation with salts or condensation. The hybrid peroxidase catalysts exhibit three times higher activity than free HRP and are able to remove three times more phenol from water compared to free HRP under similar conditions. In addition, the hybrid catalysts reduce substrate inhibition and limit inactivation from reaction products, which are common problems with free or conventionally immobilized enzymes. Reusability is improved when the HRP-magnetic nanoparticle hybrids are supported on micron-scale magnetic particles, and can be retained with a specially designed magnetically driven reactor. The performance of the hybrid catalysts makes them attractive for several industrial and environmental applications and their development might pave the way for practical applications by eliminating most of the limitations that have prevented the use of free or conventionally immobilized enzymes. © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  3. Becoming a Peroxidase: Cardiolipin-Induced Unfolding of Cytochrome c

    Science.gov (United States)

    Muenzner, Julia; Toffey, Jason R.; Hong, Yuning; Pletneva, Ekaterina V.

    2014-01-01

    Interactions of cytochrome c (cyt c) with a unique mitochondrial glycerophospholipid cardiolipin (CL) are relevant for the protein’s function in oxidative phosphorylation and apoptosis. Binding to CL-containing membranes promotes cyt c unfolding and dramatically enhances the protein’s peroxidase activity, which is critical in early stages of apoptosis. We have employed a collection of seven dansyl variants of horse heart cyt c to probe the sequence of steps in this functional transformation. Kinetic measurements have unraveled four distinct processes during CL-induced cyt c unfolding: rapid protein binding to CL liposomes; rearrangements of protein substructures with small unfolding energies; partial insertion of the protein into the lipid bilayer; and extensive protein restructuring leading to “open” extended structures. While early rearrangements depend on a hierarchy of foldons in the native structure, the later process of large-scale unfolding is influenced by protein interactions with the membrane surface. The opening of the cyt c structure exposes the heme group, which enhances the protein’s peroxidase activity and also frees the C-terminal helix to aid in the translocation of the protein through CL membranes. PMID:23713573

  4. Horseradish peroxidase-modified porous silicon for phenol monitoring

    Energy Technology Data Exchange (ETDEWEB)

    Kermad, A., E-mail: amina_energetique@yahoo.fr [Unité de Recherche Matériaux et Energies Renouvelables (URMER), Département de Physique, Faculté des Sciences, Université Abou Baker Belkaid, B.P. 119, Tlemcen 13000 (Algeria); Sam, S., E-mail: Sabrina.sam@polytechnique.edu [Centre de Recherche en Technologie des Semi-conducteurs pour l’Energétique (CRTSE), 02 Bd. Frantz-Fanon, B.P. 140, Alger-7 merveilles, Algiers (Algeria); Ghellai, N., E-mail: na_ghellai@yahoo.fr [Unité de Recherche Matériaux et Energies Renouvelables (URMER), Département de Physique, Faculté des Sciences, Université Abou Baker Belkaid, B.P. 119, Tlemcen 13000 (Algeria); Khaldi, K., E-mail: Khadidjaphy@yahoo.fr [Unité de Recherche Matériaux et Energies Renouvelables (URMER), Département de Physique, Faculté des Sciences, Université Abou Baker Belkaid, B.P. 119, Tlemcen 13000 (Algeria); Gabouze, N., E-mail: ngabouze@yahoo.fr [Centre de Recherche en Technologie des Semi-conducteurs pour l’Energétique (CRTSE), 02 Bd. Frantz-Fanon, B.P. 140, Alger-7 merveilles, Algiers (Algeria)

    2013-11-01

    Highlights: • Horseradish peroxidase enzyme (HRP) was covalently immobilized on porous silicon (PSi) surface. • Multistep strategy was used allowing the maintaining of the enzymatic activity of the immobilized enzyme. • Direct electron transfer has occurred between the immobilized enzyme and the surface. • Electrochemical measurements showed a response of HRP-modified PSi toward phenol in the presence of H{sub 2}O{sub 2}. -- Abstract: In this study, horseradish peroxidase enzyme (HRP) was covalently immobilized on porous silicon (PSi) surface using multistep strategy. First, acid terminations were generated on hydrogenated PSi surface by thermal hydrosilylation of undecylenic acid. Then, the carboxyl-terminated monolayer was transformed to active ester (succinimidyl ester) using N-hydroxysuccinimide (NHS) in the presence of the coupling agent N-ethyl-N′-(3-dimethylaminopropyl) carbodiimide (EDC). Subsequently, the enzyme was anchored on the surface via an amidation reaction. The structure of the PSi layers was observed by scanning electron microscopy (SEM). Infrared spectroscopy (FTIR) and contact angle measurements confirmed the efficiency of the modification at each step of the functionalization. Cyclic voltammetry was recorded using the HRP-modified PSi as working electrode. The results show that the enzymatic activity of the immobilized HRP is preserved and in the presence of hydrogen peroxide, the enzyme oxidizes phenolic molecules which were subsequently reduced at the modified-PSi electrode.

  5. Horseradish peroxidase-modified porous silicon for phenol monitoring

    International Nuclear Information System (INIS)

    Kermad, A.; Sam, S.; Ghellai, N.; Khaldi, K.; Gabouze, N.

    2013-01-01

    Highlights: • Horseradish peroxidase enzyme (HRP) was covalently immobilized on porous silicon (PSi) surface. • Multistep strategy was used allowing the maintaining of the enzymatic activity of the immobilized enzyme. • Direct electron transfer has occurred between the immobilized enzyme and the surface. • Electrochemical measurements showed a response of HRP-modified PSi toward phenol in the presence of H 2 O 2 . -- Abstract: In this study, horseradish peroxidase enzyme (HRP) was covalently immobilized on porous silicon (PSi) surface using multistep strategy. First, acid terminations were generated on hydrogenated PSi surface by thermal hydrosilylation of undecylenic acid. Then, the carboxyl-terminated monolayer was transformed to active ester (succinimidyl ester) using N-hydroxysuccinimide (NHS) in the presence of the coupling agent N-ethyl-N′-(3-dimethylaminopropyl) carbodiimide (EDC). Subsequently, the enzyme was anchored on the surface via an amidation reaction. The structure of the PSi layers was observed by scanning electron microscopy (SEM). Infrared spectroscopy (FTIR) and contact angle measurements confirmed the efficiency of the modification at each step of the functionalization. Cyclic voltammetry was recorded using the HRP-modified PSi as working electrode. The results show that the enzymatic activity of the immobilized HRP is preserved and in the presence of hydrogen peroxide, the enzyme oxidizes phenolic molecules which were subsequently reduced at the modified-PSi electrode

  6. Hierarchical hybrid peroxidase catalysts for remediation of phenol wastewater

    KAUST Repository

    Duan, Xiaonan; Corgié , Sté phane C.; Aneshansley, Daniel J.; Wang, Peng; Walker, Larry P.; Giannelis, Emmanuel P.

    2014-01-01

    We report a new family of hierarchical hybrid catalysts comprised of horseradish peroxidase (HRP)-magnetic nanoparticles for advanced oxidation processes and demonstrate their utility in the removal of phenol from water. The immobilized HRP catalyzes the oxidation of phenols in the presence of H2O2, producing free radicals. The phenoxy radicals react with each other in a non-enzymatic process to form polymers, which can be removed by precipitation with salts or condensation. The hybrid peroxidase catalysts exhibit three times higher activity than free HRP and are able to remove three times more phenol from water compared to free HRP under similar conditions. In addition, the hybrid catalysts reduce substrate inhibition and limit inactivation from reaction products, which are common problems with free or conventionally immobilized enzymes. Reusability is improved when the HRP-magnetic nanoparticle hybrids are supported on micron-scale magnetic particles, and can be retained with a specially designed magnetically driven reactor. The performance of the hybrid catalysts makes them attractive for several industrial and environmental applications and their development might pave the way for practical applications by eliminating most of the limitations that have prevented the use of free or conventionally immobilized enzymes. © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  7. Glutathione S-transferase M1 and T1 gene polymorphisms with consumption of high fruit-juice and vegetable diet affect antioxidant capacity in healthy adults.

    Science.gov (United States)

    Yuan, Linhong; Zhang, Ling; Ma, Weiwei; Zhou, Xin; Ji, Jian; Li, Nan; Xiao, Rong

    2013-01-01

    To our knowledge, no data have yet shown the combined effects of GSTM1/GSTT1 gene polymorphisms with high consumption of a fruit and vegetable diet on the body's antioxidant capacity. A 2-wk dietary intervention in healthy participants was conducted to test the hypothesis that the antioxidant biomarkers in individuals with different glutathione-S-transferases (GST) genotypes will be different in response to a high fruit-juice and vegetable diet. In our study, 24 healthy volunteers with different GST genotypes (12 GSTM1+/GSTT1+ and 12 GSTM1-/GSTT1- participants) consumed a controlled diet high in fruit-juice and vegetables for 2 wk. Blood and first-void urine specimens were obtained at baseline, 1-wk, and 2-wk intervals. The antioxidant capacity-related biomarkers in blood and urine were observed and recorded at the scheduled times. Erythrocyte GST and glutathione reductase (GR) activities response to a high fruit-juice and vegetable diet are GST genotype-dependent. Two weeks on the high fruit-juice and vegetable diet increased GST and GR activities in the GSTM1+/GSTT1+ group (P juice and vegetable diet than GSTM1-/GSTT1- participants. The diet intervention was effective in enhancing glutathione peroxidase and catalase activities in all participants (P 0.05). The effects of a diet rich in fruit-juice and vegetables on antioxidant capacity were dependent on GSTM1/GSTT1 genotypes. Copyright © 2013 Elsevier Inc. All rights reserved.

  8. Exogenous Spermidine Alleviates Low Temperature Injury in Mung Bean (Vigna radiata L. Seedlings by Modulating Ascorbate-Glutathione and Glyoxalase Pathway

    Directory of Open Access Journals (Sweden)

    Kamrun Nahar

    2015-12-01

    Full Text Available The role of exogenous spermidine (Spd in alleviating low temperature (LT stress in mung bean (Vigna radiata L. cv. BARI Mung-3 seedlings has been investigated. Low temperature stress modulated the non-enzymatic and enzymatic components of ascorbate-glutathione (AsA-GSH cycle, increased H2O2 content and lipid peroxidation, which indicate oxidative damage of seedlings. Low temperature reduced the leaf relative water content (RWC and destroyed leaf chlorophyll, which inhibited seedlings growth. Exogenous pretreatment of Spd in LT-affected seedlings significantly increased the contents of non-enzymatic antioxidants of AsA-GSH cycle, which include AsA and GSH. Exogenous Spd decreased dehydroascorbate (DHA, increased AsA/DHA ratio, decreased glutathione disulfide (GSSG and increased GSH/GSSG ratio under LT stress. Activities of AsA-GSH cycle enzymes such as ascorbate peroxidase (APX, monodehydroascorbate reductase (MDHAR, dehydroascorbate reductase (DHAR and glutathione reductase (GR increased after Spd pretreatment in LT affected seedlings. Thus, the oxidative stress was reduced. Protective effects of Spd are also reflected from reduction of methylglyoxal (MG toxicity by improving glyoxalase cycle components, and by maintaining osmoregulation, water status and improved seedlings growth. The present study reveals the vital roles of AsA-GSH and glyoxalase cycle in alleviating LT injury.

  9. Effect of pheniramine maleate on reperfusion injury in brain tissue.

    Science.gov (United States)

    Yürekli, Ismail; Gökalp, Orhan; Kiray, Müge; Gökalp, Gamze; Ergüneş, Kazım; Salman, Ebru; Yürekli, Banu Sarer; Satoğlu, Ismail Safa; Beşir, Yüksel; Cakır, Habib; Gürbüz, Ali

    2013-12-06

    The aim of this study was to investigate the protective effects of methylprednisolone (Pn), which is a potent anti-inflammatory agent, and pheniramine maleate (Ph), which is an antihistaminic with some anti-inflammatory effects, on reperfusion injury in brain developing after ischemia of the left lower extremity of rats. Twenty-eight randomly selected male Sprague-Dawley rats were divided into 4 groups: Group 1 was the control group, Group 2 was the sham group (I/R), Rats in Group 3 were subjected to I/R and given Ph, and rats in Group 4 were subjected to I/R and given Pn. A tourniquet was applied at the level of left groin region of subjects in the I/R group after induction of anesthesia. One h of ischemia was performed with no drug administration. In the Ph group, half of a total dose of 10 mg/kg Ph was administered intraperitoneally before ischemia and the remaining half before reperfusion. In the Pn group, subjects received a single dose of 50 mg/kg Pn intraperitoneally at the 30th min of ischemia. Brains of all subjects were removed after 24 h for examination. Malondialdehyde (MDA) levels of the prefrontal cortex were significantly lower in the Ph group than in the I/R group (p<0.05). Superoxide dismutase (SOD) and glutathione peroxidase (GPx) enzyme activities were found to be significantly higher in the Ph group than in the I/R group (p<0.05). Histological examination demonstrated that Ph had protective effects against I/R injury developing in the brain tissue. Ph has a protective effect against ischemia/reperfusion injury created experimentally in rat brains.

  10. The effects of xylitol and sorbitol on lysozyme- and peroxidase-related enzymatic and candidacidal activities.

    Science.gov (United States)

    Kim, Bum-Soo; Chang, Ji-Youn; Kim, Yoon-Young; Kho, Hong-Seop

    2015-07-01

    To investigate whether xylitol and sorbitol affect enzymatic and candidacidal activities of lysozyme, the peroxidase system, and the glucose oxidase-mediated peroxidase system. Xylitol and sorbitol were added to hen egg-white lysozyme, bovine lactoperoxidase, glucose oxidase-mediated peroxidase, and whole saliva in solution and on hydroxyapatite surfaces. The enzymatic activities of lysozyme, peroxidase, and glucose oxidase-mediated peroxidase were determined by the turbidimetric method, the NbsSCN assay, and production of oxidized o-dianisidine, respectively. Candidacidal activities were determined by comparing colony forming units using Candida albicans ATCC strains 10231, 11006, and 18804. While xylitol and sorbitol did not affect the enzymatic activity of hen egg-white lysozyme both in solution and on hydroxyapatite surfaces, they did inhibit the enzymatic activity of salivary lysozyme significantly in solution, but not on the surfaces. Xylitol and sorbitol enhanced the enzymatic activities of both bovine lactoperoxidase and salivary peroxidase significantly in a dose-dependent manner in solution, but not on the surfaces. Sorbitol, but not xylitol, inhibited the enzymatic activity of glucose oxidase-mediated peroxidase significantly. Both xylitol and sorbitol did not affect candidacidal activities of hen egg-white lysozyme, the bovine lactoperoxidase system, or the glucose oxidase-mediated bovine lactoperoxidase system. Xylitol and sorbitol inhibited salivary lysozyme activity, but enhanced both bovine lactoperoxidase and salivary peroxidase activities significantly in solution. Xylitol and sorbitol did not augment lysozyme- and peroxidase-related candidacidal activities. Copyright © 2015 Elsevier Ltd. All rights reserved.

  11. Reduced glutathione as a persistence indicator of alien plants of the Amelancheir family

    Directory of Open Access Journals (Sweden)

    L. G. Dolgova

    2009-04-01

    Full Text Available It was proved that glutathione is an important indicator of the vegetation condition and persistence. According to the amount of glutathione the studied mespilus species are adapted to the environmental conditions. Increase of the glutathione amount is caused by some abiotic factors, e.g. temperature. Some differences of the glutathione content may be explained by the plants species patterns.

  12. Do glutathione levels decline in aging human brain?

    Science.gov (United States)

    Tong, Junchao; Fitzmaurice, Paul S; Moszczynska, Anna; Mattina, Katie; Ang, Lee-Cyn; Boileau, Isabelle; Furukawa, Yoshiaki; Sailasuta, Napapon; Kish, Stephen J

    2016-04-01

    For the past 60 years a major theory of "aging" is that age-related damage is largely caused by excessive uncompensated oxidative stress. The ubiquitous tripeptide glutathione is a major antioxidant defense mechanism against reactive free radicals and has also served as a marker of changes in oxidative stress. Some (albeit conflicting) animal data suggest a loss of glutathione in brain senescence, which might compromise the ability of the aging brain to meet the demands of oxidative stress. Our objective was to establish whether advancing age is associated with glutathione deficiency in human brain. We measured reduced glutathione (GSH) levels in multiple regions of autopsied brain of normal subjects (n=74) aged one day to 99 years. Brain GSH levels during the infancy/teenage years were generally similar to those in the oldest examined adult group (76-99 years). During adulthood (23-99 years) GSH levels remained either stable (occipital cortex) or increased (caudate nucleus, frontal and cerebellar cortices). To the extent that GSH levels represent glutathione antioxidant capacity, our postmortem data suggest that human brain aging is not associated with declining glutathione status. We suggest that aged healthy human brains can maintain antioxidant capacity related to glutathione and that an age-related increase in GSH levels in some brain regions might possibly be a compensatory response to increased oxidative stress. Since our findings, although suggestive, suffer from the generic limitations of all postmortem brain studies, we also suggest the need for "replication" investigations employing the new (1)H MRS imaging procedures in living human brain. Copyright © 2016 Elsevier Inc. All rights reserved.

  13. Assessing the sensitivity of Atlantic salmon (Salmo salar) to dietary endosulfan exposure using tissue biochemistry and histology

    Energy Technology Data Exchange (ETDEWEB)

    Glover, Chris N.; Petri, Dietrich [National Institute of Nutrition and Seafood Research (NIFES), Bergen (Norway); Tollefsen, Knut-Erik [Norwegian Institute for Water Research (NIVA), Oslo (Norway); Jorum, Nanne [Skretting ARC, Stavanger (Norway); Handy, Richard D. [School of Biological Sciences, University of Plymouth, Plymouth (United Kingdom); Berntssen, Marc H.G. [National Institute of Nutrition and Seafood Research (NIFES), Bergen (Norway)], E-mail: marc.berntssen@nifes.no

    2007-10-15

    The incorporation of plant-based ingredients, and the possible carry-over of pesticides such as endosulfan, in fish feeds may present new toxicological challenges to aquacultural species. Biological responses of Atlantic salmon (Salmo salar) to a 35-day dietary endosulfan exposure at levels ranging from 4 to 710 {mu}g kg{sup -1} were assessed using tissue histology and biochemistry. Liver 7-ethoxyresorufin-O-deacetylase (EROD) activity was significantly elevated in the highest exposure group (710 {mu}g kg{sup -1}) by day 35. Other hepatic indicators of stress impacts and responses (glutathione-S-transferase and glutathione peroxidase activities and hepatic {alpha}-tocopherol content) remained unchanged. Branchial Na{sup +}, K{sup +}-ATPase activity was significantly reduced at day 14 in the highest exposure group, but returned to control levels by day 35. Conversely, intestinal Na{sup +}, K{sup +}-ATPase activity was significantly inhibited at day 35, but again only at the highest exposure level. In contrast to the biochemical results, hepatic and intestinal histology revealed effects of exposure even at the lowest dose tested (4 {mu}g kg{sup -1}). In the posterior intestine, pathology was characterised by vacuolation and fusion of villi, and in the most severe cases, loss of epithelial integrity in villi tips. In the liver the primary effects were glycogen depletion and lipidosis. These changes were typical of a generalised stress response. While histology endpoints may prove to be the most sensitive indicators of dietary endosulfan exposure, the organismal relevance of these structural changes must be considered in the absence of effects in other biomarkers at dietary levels less than 710 {mu}g kg{sup -1}.

  14. Assessing the sensitivity of Atlantic salmon (Salmo salar) to dietary endosulfan exposure using tissue biochemistry and histology

    International Nuclear Information System (INIS)

    Glover, Chris N.; Petri, Dietrich; Tollefsen, Knut-Erik; Jorum, Nanne; Handy, Richard D.; Berntssen, Marc H.G.

    2007-01-01

    The incorporation of plant-based ingredients, and the possible carry-over of pesticides such as endosulfan, in fish feeds may present new toxicological challenges to aquacultural species. Biological responses of Atlantic salmon (Salmo salar) to a 35-day dietary endosulfan exposure at levels ranging from 4 to 710 μg kg -1 were assessed using tissue histology and biochemistry. Liver 7-ethoxyresorufin-O-deacetylase (EROD) activity was significantly elevated in the highest exposure group (710 μg kg -1 ) by day 35. Other hepatic indicators of stress impacts and responses (glutathione-S-transferase and glutathione peroxidase activities and hepatic α-tocopherol content) remained unchanged. Branchial Na + , K + -ATPase activity was significantly reduced at day 14 in the highest exposure group, but returned to control levels by day 35. Conversely, intestinal Na + , K + -ATPase activity was significantly inhibited at day 35, but again only at the highest exposure level. In contrast to the biochemical results, hepatic and intestinal histology revealed effects of exposure even at the lowest dose tested (4 μg kg -1 ). In the posterior intestine, pathology was characterised by vacuolation and fusion of villi, and in the most severe cases, loss of epithelial integrity in villi tips. In the liver the primary effects were glycogen depletion and lipidosis. These changes were typical of a generalised stress response. While histology endpoints may prove to be the most sensitive indicators of dietary endosulfan exposure, the organismal relevance of these structural changes must be considered in the absence of effects in other biomarkers at dietary levels less than 710 μg kg -1

  15. Lipid accumulation, oxidative stress and immune-related molecules affected by tributyltin exposure in muscle tissues of rare minnow (Gobiocypris rarus).

    Science.gov (United States)

    Zhang, Jiliang; Zhang, Chunnuan; Ma, Dongdong; Liu, Min; Huang, Shuntao

    2017-12-01

    Tributyltin (TBT) is reported to induce adipogenesis in fish, which might affect nutritional qualities and health status. Muscle tissues account for the majority of body mass, and have been described as a major site of fat deposition and an immunologically active organ. Therefore, the present study aims to evaluate whether chronic exposures of TBT, at environmental concentrations of 1, 10 and 100 ng/L, affects lipid accumulation, oxidative stress and immune status in muscle tissues of rare minnow (Gobiocypris rarus). After 60 d of exposure, TBT increased contents of total lipid, total cholesterol, triglyceride and fatty acids in muscle tissues. Interestingly, TBT exposure disrupted fatty acid composition and increased contents of unsaturated fatty acids (such as eicosapentaenoic acid and docosahexaenoic acid) in muscle tissues, which might be a response to preserve membrane functions from TBT exposure. Meanwhile, the concentrations of hepatic fatty acid desaturase 2 (Δ6-desaturase) and stearoyl-CoA desaturase (Δ9-desaturase) were increased after TBT exposure, which might contribute the increase of unsaturated fatty acids. Furthermore, TBT increased muscle lipid peroxidation products, antioxidant enzymes (superoxide dismutase, catalase and glutathione peroxidase), and the expression of immune-related molecules (tumor necrosis factor alpha, interleukin 1 beta and nuclear factor kappa B) in muscle tissues. The disruption of TBT on the lipid accumulation, oxidative stress and immune-toxic effects in muscle tissues of fish might reduce nutritional qualities, and affect growth and health status, which might pose a constant and serious threat to fish and result in economic loss in aquaculture. Copyright © 2017 Elsevier Ltd. All rights reserved.

  16. Effect of glutathione aerosol on oxidant-antioxidant imbalance in idiopathic pulmonary fibrosis.

    Science.gov (United States)

    Borok, Z; Buhl, R; Grimes, G J; Bokser, A D; Hubbard, R C; Holroyd, K J; Roum, J H; Czerski, D B; Cantin, A M; Crystal, R G

    1991-07-27

    Idiopathic pulmonary fibrosis (IPF) is characterised by alveolar inflammation, exaggerated release of oxidants, and subnormal concentrations of the antioxidant glutathione in respiratory epithelial lining fluid (ELF). Glutathione (600 mg twice daily for 3 days) was given by aerosol to 10 patients with IPF. Total ELF glutathione rose transiently, ELF oxidised glutathione concentrations increased, and there was a decrease in spontaneous superoxide anion release by alveolar macrophages. Thus, glutathione by aerosol could be a means of reversing the oxidant-antioxidant imbalance in IPF.

  17. Asparagus byproducts as a new source of peroxidases.

    Science.gov (United States)

    Jaramillo-Carmona, Sara; Lopez, Sergio; Vazquez-Castilla, Sara; Rodriguez-Arcos, Rocio; Jimenez-Araujo, Ana; Guillen-Bejarano, Rafael

    2013-07-03

    Soluble peroxidase (POD) from asparagus byproducts was purified by ion exchange chromatographies, and its kinetic and catalytic properties were studied. The isoelectric point of the purified isoperoxidases was 9.1, and the optimum pH and temperature values were 4.0 and 25 °C, respectively. The cationic asparagus POD (CAP) midpoint inactivation temperature was 57 °C, which favors its use in industrial processes. The Km values of cationic asparagus POD for H₂O₂ and ABTS were 0.318 and 0.634 mM, respectively. The purified CAP is economically obtained from raw materials using a simple protocol and possesses features that make it advantageous for the potential use of this enzyme in a large number of processes with demonstrated requirements of thermostable POD. The results indicate that CAP can be used as a potential candidate for removing phenolic contaminants.

  18. Double Antibody EIA of Cortisol Using Peroxidase As Label

    International Nuclear Information System (INIS)

    Karim, F.M.; Hamad, A.W.R.; Hashim, A.M.

    1998-01-01

    An enzyme immunoassay (EIA) technique for plasma cortisol was established by using cortisol-3 (carboxymethyl) oxime covalently linked to the horseradish peroxidase as the label. An antibody raised in the rabbits against cortisol-3-(carboxy-methyl) oxime-bovline serum albumin was used as the first anti-body. Sheep anti-rabbit gamma-globulin serum with 8 percent poly-ethyleneglycol were used to separate antibody-bound and free cortisol. The enzyme activity of the bound fraction was measured with ortho-phenylene diamine as substrate. The procedure performed at room temperature was evaluated by sensitivity (50 pg/ tube). The correlation coefficient between our enzyme immunoassay technique and radioimmunoassay technique for determination of plasma cortisol was 97 percent

  19. Polymerization reactivity of sulfomethylated alkali lignin modified with horseradish peroxidase.

    Science.gov (United States)

    Yang, Dongjie; Wu, Xiaolei; Qiu, Xueqing; Chang, Yaqi; Lou, Hongming

    2014-03-01

    Alkali lignin (AL) was employed as raw materials in the present study. Sulfomethylation was conducted to improve the solubility of AL, while sulfomethylated alkali lignin (SAL) was further polymerized by horseradish peroxidase (HRP). HRP modification caused a significant increase in molecular weight of SAL which was over 20 times. It was also found to increase the amount of sulfonic and carboxyl groups while decrease the amount of phenolic and methoxyl groups in SAL. The adsorption quantity of self-assembled SAL film was improved after HRP modification. Sulfonation and HRP modification were mutually promoted. The polymerization reactivity of SAL in HRP modification was increased with its sulfonation degree. Meanwhile, HRP modification facilitated SAL's radical-sulfonation reaction. Copyright © 2014. Published by Elsevier Ltd.

  20. Optimalization of the peroxidase production by tissue cultures of horseradish in vitro

    Czech Academy of Sciences Publication Activity Database

    Soudek, Petr; Podlipná, Radka; Maršík, Petr; Vaněk, Tomáš

    2005-01-01

    Roč. 49, č. 4 (2005), s. 487-492 ISSN 0006-3134 R&D Projects: GA ČR(CZ) GA526/04/0135 Institutional research plan: CEZ:AV0Z40550506 Keywords : agrobacterium rhizogenes * Armoracia rusticana * cadmium Subject RIV: DK - Soil Contamination ; De-contamination incl. Pesticides Impact factor: 0.792, year: 2005

  1. Purification of peroxidase from Horseradish (Armoracia rusticana) roots.

    Science.gov (United States)

    Lavery, Christopher B; Macinnis, Morgan C; Macdonald, M Jason; Williams, Joanna Bassey; Spencer, Colin A; Burke, Alicia A; Irwin, David J G; D'Cunha, Godwin B

    2010-08-11

    Peroxidase (EC 1.11.1.7) from horseradish ( Armoracia rusticana ) roots was purified using a simple, rapid, three-step procedure: ultrasonication, ammonium sulfate salt precipitation, and hydrophobic interaction chromatography on phenyl Sepharose CL-4B. The preparation gave an overall yield of 71%, 291-fold purification, and a high specific activity of 772 U mg(-1) protein. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis revealed that the purified enzyme was homogeneous and had a molecular weight of approximately 40 kDa. The isolated enzyme had an isoelectric point of 8.8 and a Reinheitszahl value of 3.39 and was stable when stored in the presence of glycerol at -20 degrees C, with >95% retention of original enzyme activity for at least 6 months. Maximal activity of purified horseradish peroxidase (HRP) was obtained under different optimized conditions: substrate (guaiacol and H(2)O(2)) concentrations (0.5 and 0.3 mM, respectively), type of buffer (50 mM phosphate buffer), pH (7.0), time (1.0 min), and temperature of incubation (30 degrees C). In addition, the effect of HRP and H(2)O(2) in a neutral-buffered aqueous solution for the oxidation of phenol and 2-chlorophenol substrates was also studied. Different conditions including concentrations of phenol/2-chlorophenol, H(2)O(2), and enzyme, time, pH, and temperature were standardized for the maximal activity of HRP with these substrates; under these optimal conditions 89.6 and 91.4% oxidations of phenol and 2-chlorophenol were obtained, respectively. The data generated from this work could have direct implications in studies on the commercial production of this biotechnologically important enzyme and its stability in different media.

  2. Thyroid peroxidase: evidence for disease gene exclusion in Pendred's syndrome.

    Science.gov (United States)

    Gausden, E; Armour, J A; Coyle, B; Coffey, R; Hochberg, Z; Pembrey, M; Britton, K E; Grossman, A; Reardon, W; Trembath, R

    1996-04-01

    Pendred's syndrome is an association between congenital neurosensory deafness and goitre with abnormal discharge of iodide following perchlorate challenge, indicating a defect of iodide organification. Although Pendred's syndrome may cause up to 7.5% of all cases of congenital deafness, the molecular basis of the association between the hearing loss and the thyroid organification defect remains unknown. We chose to investigate the role of the thyroid peroxidase (TPO) gene as the genetic defect in Pendred's syndrome. A highly informative variable number tandem repeat (VNTR), located 1.5 kb downstream of exon 10 of the TPO gene, was used to search for genetic linkage in multiple sibships affected by Pendred's syndrome. Seven kindreds were recruited from the UK, each with at least two affected members. We have also examined a large inbred Israeli family with two affected offspring and five unaffected children. Individuals were assigned affected status based on the characteristic clinical features of Pendred's syndrome, namely the presence of congenital sensorineural hearing loss and the appearance in early life of a goitre. Additionally, at least one affected member from each sibship had a characteristic positive perchlorate discharge test (Morgans & Trotter, 1958). PCR amplification of genomic DNA at the TPO VNTR allowed assignment of genotypes to each individual and the calculation of a two-point LOD score. In six of the nine sibships analysed we found obligatory recombination between TPO and Pendred's syndrome. Non-complementation observed in affected parents with an affected offspring excluded TPO in an affected sibship with genotype sharing and supports a hypothesis of genetic homogeneity for Pendred's syndrome. In two sibships, mutation of the TPO gene as the cause of Pendred's syndrome could not be excluded. These data suggest that defects at the thyroid peroxidase locus on chromosome 2 are not the major cause of Pendred's syndrome.

  3. [Appreciation of selenium concentration in blood and tissues of male rat as a result of diet ingredients changes and its supplementation with chosen group B vitamins].

    Science.gov (United States)

    Friedrich, Mariola; Goluch-Koniuszy, Zuzanna; Dolot, Anna; Pilarczyk, Bogumiła

    2011-01-01

    The influence of diet ingredients and its supplementation with chosen B group vitamins on concentration of selenium in blood serum and tissues and activity of glutathione peroxidase in blood and liver of male rats was examined in the conducted experiment. The animals, aged 5 months, were divided into three groups and fed ad libitum with granulated mixes. Group I with basic mix containing among other things full grains, Group II with modified mix in which full grains were exchanged for wheat flour and in part with saccharose and Group III with modified mix supplemented in excess with vitamins B1, B2, B6 and PP. The experiment was conducted for six weeks during which the amount of consumed feeding stuff was calculated currently and once a week body mass of the animals was checked. When the experiment was finished the activity of GSH-Px was determined by spectrophotometric method in blood and liver whereas concentration of selenium in blood serum, muscles and in liver by fluorometric method. It was ascertained that the change of diet ingredients and its supplementation with chosen group B vitamins was in favour of lowering the amount of selenium in the examined tissues, and the decrease was not only the result of lower amount of the consumed element, but also of its increased usage, forced by the changes taking place under the influence of diet components and its supplementation.

  4. Alterations to proteome and tissue recovery responses in fish liver caused by a short-term combination treatment with cadmium and benzo[a]pyrene

    International Nuclear Information System (INIS)

    Costa, P.M.; Chicano-Galvez, E.; Lopez Barea, J.; DelValls, T.A.; Costa, M.H.

    2010-01-01

    The livers of soles (Solea senegalensis) injected with subacute doses of cadmium (Cd), benzo[a]pyrene (B[a]P), or their combination, were screened for alterations to cytosolic protein expression patterns, complemented by cytological and histological analyses. Cadmium and B[a]P, but not combined, induced hepatocyte apoptosis and Kupfer cell hyperplasia. Proteomics, however, suggested that apoptosis was triggered through distinct pathways. Cadmium and B[a]P caused upregulation of different anti-oxidative enzymes (peroxiredoxin and glutathione peroxidase, respectively) although co-exposure impaired induction. Similarly, apoptosis was inhibited by co-exposure, to which may have contributed a synergistic upregulation of tissue metalloproteinase inhibitor, β-actin and a lipid transport protein. The regulation factors of nine out of eleven identified proteins of different types revealed antagonistic or synergistic effects between Cd and B[a]P at the prospected doses after 24 h of exposure. The results indicate that co-exposure to Cd and B[a]P may enhance toxicity by impairing specific responses and not through cumulative damage. - The interaction between cadmium and benzo[a]pyrene impairs specific responses to toxicity and tissue repair mechanisms.

  5. [Interference of vitamin E on the brain tissue damage by electromagnetic radiation of cell phone in pregnant and fetal rats].

    Science.gov (United States)

    Gao, Xian; Luo, Rui; Ma, Bin; Wang, Hui; Liu, Tian; Zhang, Jing; Lian, Zhishun; Cui, Xi

    2013-07-01

    To investigate the interlerence ot vitamin E on brain tissue damage by electromagnetic radiation of cell phone in pregnant and fetal rats. 40 pregnant rats were randomly divided into five groups (positive control, negative control, low, middle and high dosage of vitamin E groups). The low, middle and high dosage of vitamin E groups were supplemented with 5, 15 and 30 mg/ml vitamin E respectively since the first day of pregnancy. And the negative control group and the positive control group were given peanut oil without vitamin E. All groups except for the negative control group were exposed to 900MHz intensity of cell phone radiation for one hour each time, three times per day for 21 days. After accouchement, the right hippocampus tissue of fetal rats in each group was taken and observed under electron microscope. The vitality of superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px), and the content of malondialdehyde (MDA) in pregnant and fetal rats' brain tissue were tested. Compared with the negative control group, the chondriosomes in neuron and neuroglia of brain tissues was swelling, mild edema was found around the capillary, chromatin was concentrated and collected, and bubbles were formed in vascular endothelial cells (VEC) in the positive fetal rat control group, whereas the above phenomenon was un-conspicuous in the middle and high dosage of vitamin E groups. We can see uniform chromatin, abundant mitochondrion, rough endoplasmic reticulum and free ribosomes in the high dosage group. The apoptosis has not fond in all groups'sections. In the antioxidase activity analysis, compared with the negative control group, the vitality of SOD and GSH-Px significantly decreased and the content of MDA significantly increased both in the pregnant and fetal rats positive control group (P electromagnetic radiation of cell phone in pregnant rats and fetal rats.

  6. Glutathione-dependent responses of plants to drought: a review

    Directory of Open Access Journals (Sweden)

    Mateusz Labudda

    2014-02-01

    Full Text Available Water is a renewable resource. However, with the human population growth, economic development and improved living standards, the world’s supply of fresh water is steadily decreasing and consequently water resources for agricultural production are limited and diminishing. Water deficiency is a significant problem in agriculture and increasing efforts are currently being made to understand plant tolerance mechanisms and to develop new tools (especially molecular that could underpin plant breeding and cultivation. However, the biochemical and molecular mechanisms of plant water deficit tolerance are not fully understood, and the data available is incomplete. Here, we review the significance of glutathione and its related enzymes in plant responses to drought. Firstly, the roles of reduced glutathione and reduced/oxidized glutathione ratio, are discussed, followed by an extensive discussion of glutathione related enzymes, which play an important role in plant responses to drought. Special attention is given to the S-glutathionylation of proteins, which is involved in cell metabolism regulation and redox signaling in photosynthetic organisms subjected to abiotic stress. The review concludes with a brief overview of future perspectives for the involvement of glutathione and related enzymes in drought stress responses.

  7. Antioxidant role of glutathione S-transferases: 4-Hydroxynonenal, a key molecule in stress-mediated signaling

    International Nuclear Information System (INIS)

    Singhal, Sharad S.; Singh, Sharda P.; Singhal, Preeti; Horne, David; Singhal, Jyotsana; Awasthi, Sanjay

    2015-01-01

    4-Hydroxy-2-trans-nonenal (4HNE), one of the major end products of lipid peroxidation (LPO), has been shown to induce apoptosis in a variety of cell lines. It appears to modulate signaling processes in more than one way because it has been suggested to have a role in signaling for differentiation and proliferation. It has been known that glutathione S-transferases (GSTs) can reduce lipid hydroperoxides through their Se-independent glutathione-peroxidase activity and that these enzymes can also detoxify LPO end-products such as 4HNE. Available evidence from earlier studies together with results of recent studies in our laboratories strongly suggests that LPO products, particularly hydroperoxides and 4HNE, are involved in the mechanisms of stress-mediated signaling and that it can be modulated by the alpha-class GSTs through the regulation of the intracellular concentrations of 4HNE. We demonstrate that 4HNE induced apoptosis in various cell lines is accompanied with c-Jun-N-terminal kinase (JNK) and caspase-3 activation. Cells exposed to mild, transient heat or oxidative stress acquire the capacity to exclude intracellular 4HNE at a faster rate by inducing GSTA4-4 which conjugates 4HNE to glutathione (GSH), and RLIP76 which mediates the ATP-dependent transport of the GSH-conjugate of 4HNE (GS-HNE). The balance between formation and exclusion promotes different cellular processes — higher concentrations of 4HNE promote apoptosis; whereas, lower concentrations promote proliferation. In this article, we provide a brief summary of the cellular effects of 4HNE, followed by a review of its GST-catalyzed detoxification, with an emphasis on the structural attributes that play an important role in the interactions with alpha-class GSTA4-4. Taken together, 4HNE is a key signaling molecule and that GSTs being determinants of its intracellular concentrations, can regulate stress-mediated signaling, are reviewed in this article. - Highlights: • GSTs are the major

  8. Magnetic resonance spectral characterization of the heme active site of Coprinus cinereus peroxidase

    International Nuclear Information System (INIS)

    Lukat, G.S.; Rodgers, K.R.; Jabro, M.N.; Goff, H.M.

    1989-01-01

    Examination of the peroxidase isolated from the inkcap Basidiomycete Coprinus cinereus shows that the 42,000-dalton enzyme contains a protoheme IX prosthetic group. Reactivity assays and the electronic absorption spectra of native Coprinus peroxidase and several of its ligand complexes indicate that this enzyme has characteristics similar to those reported for horseradish peroxidase. In this paper, the authors characterize the H 2 O 2 -oxidized forms of Coprinus peroxidase compounds I, II, and III by electronic absorption and magnetic resonance spectroscopies. Electron paramagnetic resonance (EPR) and nuclear magnetic resonance (NMR) studies of this Coprinus peroxidase indicate the presence of high-spin Fe(III) in the native protein and a number of differences between the heme site of Coprinus peroxidase and horseradish peroxidase. Carbon-13 (of the ferrous CO adduct) and nitrogen-15 (of the cyanide complex) NMR studies together with proton NMR studies of the native and cyanide-complexed Caprinus peroxidase are consistent with coordination of a proximal histidine ligand. The EPR spectrum of the ferrous NO complex is also reported. Protein reconstitution with deuterated hemin has facilitated the assignment of the heme methyl resonances in the proton NMR spectrum

  9. Use of an immuno-peroxidase staining method for the detection of ...

    African Journals Online (AJOL)

    Immunopurified antigens of axenic E. histolytica were used to produce rabbit hyper-immune sera. Immunoglobulin G (IgG) was purified from hyper-immune sera and coupled to peroxidase using a two-step procedure. The IgG-peroxidase conjugate was then evaluated by detection of E. histolytica in 128 stool samples and ...

  10. Purification and characterization of an intracellular catalase-peroxidase from Penicillium simplicissimum

    NARCIS (Netherlands)

    Fraaije, Marco W.; Roubroeks, Hanno P.; Hagen, Wilfred R.; Berkel, Willem J.H. van

    1996-01-01

    The first dimeric catalase-peroxidase of eucaryotic origin, an intracellular hydroperoxidase from Penicillium simplicissimum which exhibited both catalase and peroxidase activities, has been isolated. The enzyme has an apparent molecular mass of about 170 kDa and is composed of two identical

  11. Interactive effects of herbicide and enhanced UV-B on growth, oxidative damage and the ascorbate-glutathione cycle in two Azolla species.

    Science.gov (United States)

    Prasad, Sheo Mohan; Kumar, Sushil; Parihar, Parul; Singh, Rachana

    2016-11-01

    A field experiment was conducted to investigate the impact of alone and combined exposures of herbicide pretilachlor (5, 10 and 20μgml(-1)) and enhanced UV-B radiation (UV-B1; ambient +2.2kJm(-2) day(-1) and UV-B2; ambient +4.4kJm(-2) day(-1)) on growth, oxidative stress and the ascorbate-glutathione (AsA-GSH) cycle in two agronomically important Azolla spp. viz., Azolla microphylla and Azolla pinnata. Decreased relative growth rate (RGR) in both the species under tested stress could be linked to enhanced oxidative stress, thus higher H2O2 accumulation was observed, that in turn might have caused severe damage to lipids and proteins, thereby decreasing membrane stability. The effects were exacerbated when spp. were exposed to combined treatments of enhanced UV-B and pretilachlor. Detoxification of H2O2 is regulated by enzymes/metabolites of AsA-GSH cycle such as ascorbate peroxidase (APX) and glutathione reductase (GR) activity that were found to be stimulated. While, dehydroascorabte reductase (DHAR) activity, and the amount of metabolites: ascorbate (AsA), glutathione (GSH) and ratios of reduced/oxidized AsA (AsA/DHA) and GSH (GSH/GSSG), showed significant reduction with increasing doses of both the stressors, either applied alone or in combination. Glutathione-S-transferase (GST), an enzyme involved in scavenging of xenobiotics, was found to be stimulated under the tested stress. This study suggests that decline in DHAR activity and in AsA/DHA ratio might have led to enhanced H2O2 accumulation, thus decreased RGR was noticed under tested stress in both the species and the effect was more pronounced in A. pinnata. Owing to better performance of AsA-GSH cycle in A. microphylla, this study substantiates the view that A. microphylla is more tolerant than A. pinnata. Copyright © 2016 Elsevier Inc. All rights reserved.

  12. Atypical Thioredoxins in Poplar: The Glutathione-Dependent Thioredoxin-Like 2.1 Supports the Activity of Target Enzymes Possessing a Single Redox Active Cysteine1[W

    Science.gov (United States)

    Chibani, Kamel; Tarrago, Lionel; Gualberto, José Manuel; Wingsle, Gunnar; Rey, Pascal; Jacquot, Jean-Pierre; Rouhier, Nicolas

    2012-01-01

    Plant thioredoxins (Trxs) constitute a complex family of thiol oxidoreductases generally sharing a WCGPC active site sequence. Some recently identified plant Trxs (Clot, Trx-like1 and -2, Trx-lilium1, -2, and -3) display atypical active site sequences with altered residues between the two conserved cysteines. The transcript expression patterns, subcellular localizations, and biochemical properties of some representative poplar (Populus spp.) isoforms were investigated. Measurements of transcript levels for the 10 members in poplar organs indicate that most genes are constitutively expressed. Using transient expression of green fluorescent protein fusions, Clot and Trx-like1 were found to be mainly cytosolic, whereas Trx-like2.1 was located in plastids. All soluble recombinant proteins, except Clot, exhibited insulin reductase activity, although with variable efficiencies. Whereas Trx-like2.1 and Trx-lilium2.2 were efficiently regenerated both by NADPH-Trx reductase and glutathione, none of the proteins were reduced by the ferredoxin-Trx reductase. Only Trx-like2.1 supports the activity of plastidial thiol peroxidases and methionine sulfoxide reductases employing a single cysteine residue for catalysis and using a glutathione recycling system. The second active site cysteine of Trx-like2.1 is dispensable for this reaction, indicating that the protein possesses a glutaredoxin-like activity. Interestingly, the Trx-like2.1 active site replacement, from WCRKC to WCGPC, suppresses its capacity to use glutathione as a reductant but is sufficient to allow the regeneration of target proteins employing two cysteines for catalysis, indicating that the nature of the residues composing the active site sequence is crucial for substrate selectivity/recognition. This study provides another example of the cross talk existing between the glutathione/glutaredoxin and Trx-dependent pathways. PMID:22523226

  13. Androgenic Regulation of White Adipose Tissue-Prostate Cancer Interactions

    Science.gov (United States)

    2015-08-01

    Symbol Entrez Gene Name Fold Change GPX5 glutathione peroxidase 5 (epididymal androgen-related protein) 13.6 SPAG11B sperm associated antigen 11B 13.0...family 2, subfamily F, polypeptide 1 4.8 HBD hemoglobin, delta 4.6 Down-regulated  Symbol Entrez Gene Name Fold Change SPAG11B sperm associated antigen...Cxcl5 and Mac-3 IHC staining results, we used the manual function to count the stromal cells that stained posi- tively on 20 images acquired randomly at

  14. Albumin-gold-glutathione is a probable auranofin metabolite

    International Nuclear Information System (INIS)

    Shaw, C.F. III; Coffer, M.; Isab, A.A.

    1989-01-01

    The newly licensed gold drug, auranofin ((2,3,4,6-tetra-O-acetyl-β-1-D-gluco-pyranosato-S-)triethylphoshine-gold(I)) crosses cell membranes and enters cells which are inaccessible to parenteral gold drugs. In vivo, the triethylphosphine ligand and gold of auranofin, but not the thio-sugar moiety, accumulate in and subsequently efflux from red blood cells (RBCs). Extracellular albumin increases in the extent of gold efflux and acts as a gold binding site. The rate of efflux is first-order in RBC gold concentration. Studies using RBCs in which labelled [ 14 C]-glutathione is generated in situ incorporation of [ 14 C]- glycine demonstrate that glutathione also effluxes from the RBCs and forms a gold-glutathione-albumin complex. This may be the immunopharmacologically active complex

  15. Effects of Electroacupuncture on Learning, Memory and Formation System of Free Radicals in Brain Tissues of Vascular Dementia Model Rats

    Institute of Scientific and Technical Information of China (English)

    王黎; 唐纯志; 赖新生

    2004-01-01

    In order to observe the regulative effect of electro-acupuncture on the formation system of free radicals in the brain tissues and learning and memory in vascular dementia (VD) model rats, the Morris's water labyrinth was used for testing the learning ability and memory in VD model rats made by 4-vessel occlusion method, and the activities or contents of nitric oxide (NO), NO synthase (NOS), superoxide dismutase (SOD), malondialdehyde (MDA), glutathione peroxidase (GSH-Px) were determined. Results showed that the mean escape latency in the electro-acupuncture group was markedly reduced in place test, and the times swam the place of the plate-form in the original plate-form quadrant were significantly more than those in the rest three quadrants in spatia1 probe test as compared with the model group. In the electro-acupuncture group and the nimodipine group the contents of NO and MDA and the activity of NOS were decreased, while the activities of SOD and GSH-Px were increased. It is indicated that electro-acupuncture can modulate the production and clearance of free radicals, and improve the ability of learning and memory of the VD model rats.

  16. Oxidative stress and antioxidant defence markers in muscle tissue of rainbow trout (Oncorhynchus mykiss after vaccination against Yersinia ruckeri

    Directory of Open Access Journals (Sweden)

    Tkachenko Halyna

    2016-03-01

    Full Text Available Introduction: The goal of this study was to assess the influence of vaccination against enteric redmouth disease on oxidative stress biomarkers and antioxidant defence in the muscle tissue of rainbow trout (Oncorhynchus mykiss Walbaum vaccinated against Yersinia ruckeri in the first and second month after immunisation. Material and Methods: Healthy fish were vaccinated orally with inactivated whole cells of a virulent strain of Y. ruckeri. One and two months after immunisation the muscle samples were collected. Results: No significant difference was noted in lipid peroxidation level in either the first or second month after vaccination, while aldehydic and ketonic derivatives of oxidatively modified proteins (OMB in the vaccinated group were significantly lower in the second month compared to those in the first month after vaccination (P < 0.05. The content of ketonic derivatives of OMB in muscles in the first month after immunisation was higher compared to untreated control. All these culminated in a depletion of glutathione peroxidase (GPx activity and low level of total antioxidant capacity (TAC. Conclusion: Correlations between catalase activity and lipid peroxidation and TAC confirmed the pivotal role of catalase in antioxidant defence during immunisation. From a broader perspective, it is suggested that immunisation of fish with Yersinia vaccine is associated with induced free radical formation and oxidative stress. Free radicals would therefore be at least partially responsible for the induction of both humoral and cellular elements of the immunity and increased protective immunity against Y. ruckeri infection.

  17. Detoxification and antioxidant effects of garlic and curcumin in Oreochromis niloticus injected with aflatoxin B₁ with reference to gene expression of glutathione peroxidase (GPx) by RT-PCR.

    Science.gov (United States)

    El-Barbary, Manal I

    2016-04-01

    The present study aims to investigate the effects of both garlic and curcumin through evaluating their therapeutic properties as antioxidants on liver and kidney functions, hepatic antioxidants and GPx gene expression against aflatoxicosis of O. niloticus. In total, 180 of tilapia were divided into ten groups; T1 represented the negative control fed on a basal diet, and T2 was injected with a single intraperitoneal (i.p.) dose of AFB1 (6 mg/kg b.w.). Fish in T3-T6 were fed on a basal diet supplemented with both garlic (T3 and T4) and curcumin (T5 and T6) at the two concentrations of 10 and 20 g/kg diet, respectively. Fish in T7-T10 groups were injected with AFB1 and fed on the garlic (T7 and T8) and curcumin (T9 and T10) dietaries. The results showed that AFB1 has significant potency for increasing the activity of plasma AST, ALT, creatinine and uric acid values, and hepatic MDA as well as for reducing the concentrations of plasma TP, AL, GL and hepatic activity of TAC, while AFB1 led to up-regulated GPx gene expression when compared to the control (T1). These harmful effects of AFB1 were alleviated due to the garlic and curcumin dietaries in some studied parameters. Garlic reflected the highest induction of gene expression (T7); however, curcumin showed significant down-regulated (T9). These results concluded that the effects of garlic were better than curcumin at the two concentrations and the low concentration of them is more beneficial than the high concentration when it used against AFB1 in O. niloticus.

  18. Activity of glutathione peroxidase (GGSH-Px) in the blood of ewes and their lambs receiving the selenium-enriched unicellular alga Chlorella

    Czech Academy of Sciences Publication Activity Database

    Trávníček, J.; Racek, J.; Trefil, L.; Rodinová, H.; Kroupová, V.; Illek, J.; Doucha, Jiří; Písek, L.

    2008-01-01

    Roč. 53, č. 7 (2008), s. 292-298 ISSN 1212-1819 Institutional research plan: CEZ:AV0Z50200510 Keywords : selenite * organic selenium * blood selenium Subject RIV: EE - Microbiology, Virology Impact factor: 0.735, year: 2008

  19. Differences in activities of antioxidant superoxide dismutase, glutathione peroxidase and prooxidant xanthine oxidoreductase/xanthine oxidase in the normal corneal epithelium of various mammalia

    Czech Academy of Sciences Publication Activity Database

    Andonova, Janetta; Pláteník, J.; Vejražka, M.; Štípek, S.; Ardan, Taras; Čejka, Čestmír; Midelfart, A.; Čejková, Jitka

    2007-01-01

    Roč. 56, č. 1 (2007), s. 105-112 ISSN 0862-8408 R&D Projects: GA ČR GA304/06/1379 Institutional research plan: CEZ:AV0Z50390512 Keywords : Mammalia * Cornea * Epithelium Subject RIV: FF - HEENT, Dentistry Impact factor: 1.505, year: 2007

  20. Age-related changes in superoxide dismutase, glutathione peroxidase, catalase and xanthine oxidoreductase/xanthine oxidase activities in the rabbit cornea

    Czech Academy of Sciences Publication Activity Database

    Čejková, Jitka; Vejražka, M.; Pláteník, J.; Štípek, S.

    2004-01-01

    Roč. 39, - (2004), s. 1537-1543 ISSN 0531-5565 R&D Projects: GA ČR GA304/03/0419 Institutional research plan: CEZ:AV0Z5039906; CEZ:AV0Z5008914 Keywords : aging * cornea Subject RIV: FF - HEENT, Dentistry Impact factor: 2.880, year: 2004

  1. Ginsenoside Re protects against phencyclidine-induced behavioral changes and mitochondrial dysfunction via interactive modulation of glutathione peroxidase-1 and NADPH oxidase in the dorsolateral cortex of mice.

    Science.gov (United States)

    Tran, The-Vinh; Shin, Eun-Joo; Dang, Duy-Khanh; Ko, Sung Kwon; Jeong, Ji Hoon; Nah, Seung-Yeol; Jang, Choon-Gon; Lee, Yu Jeung; Toriumi, Kazuya; Nabeshima, Toshitaka; Kim, Hyoung-Chun

    2017-12-01

    We investigated whether ginsenoside Re (Re) modulates phencyclidine (PCP)-induced sociability deficits and recognition memory impairments to extend our recent finding. We examined the role of GPx-1 gene in the pharmacological activity of Re against mitochondrial dysfunction induced by PCP in the dorsolateral cortex of mice. Since mitochondrial oxidative stress activates NADPH oxidase (PHOX), we applied PHOX inhibitor apocynin for evaluating interactive modulation between GPx-1 and PHOX against PCP neurotoxicity. Sociability deficits and recognition memory impairments induced by PCP were more pronounced in GPx-1 knockout (KO) than in wild type (WT) mice. PCP-induced mitochondrial oxidative stress, mitochondrial dysfunction, and membrane translocation of p47phox were more evident in GPx-1 KO than in WT. Re treatment significantly attenuated PCP-induced neurotoxic changes. Re also significantly attenuated PCP-induced sociability deficits and recognition memory impairments. The attenuation by Re was comparable to that by apocynin. The attenuation was more obvious in GPx-1 KO than in WT. Importantly, apocynin did not show any additional positive effects on the neuroprotective activity of Re, indicating that PHOX is a molecular target for therapeutic activity of Re. Our results suggest that Re requires interactive modulation between GPx activity and PHOX (p47phox) to exhibit neuroprotective potentials against PCP insult. Copyright © 2017 Elsevier Ltd. All rights reserved.

  2. Endoplasmic reticulum transport of glutathione by Sec61 is regulated by Ero1 and Bip

    DEFF Research Database (Denmark)

    Ponsero, Alise J.; Igbaria, Aeid; Darch, Maxwell A.

    2017-01-01

    In the endoplasmic reticulum (ER), Ero1 catalyzes disulfide bond formation and promotes glutathione (GSH) oxidation to GSSG. Since GSSG cannot be reduced in the ER, maintenance of the ER glutathione redox state and levels likely depends on ER glutathione import and GSSG export. We used quantitative...... oxidation through Ero1 reductive activation, which inhibits glutathione import in a negative regulatory loop. During ER stress, transport is activated by UPR-dependent Ero1 induction, and cytosolic glutathione levels increase. Thus, the ER redox poise is tuned by reciprocal control of glutathione import...... by reduction, causing Bip oxidation and inhibition of glutathione transport. Coupling of glutathione ER import to Ero1 activation provides a basis for glutathione ER redox poise maintenance....

  3. Human thyroid peroxidase: complete cDNA and protein sequence, chromosome mapping, and identification of two alternately spliced mRNAs

    International Nuclear Information System (INIS)

    Kimura, S.; Kotani, T.; McBride, O.W.; Umeki, K.; Hirai, K.; Nakayama, T.; Ohtaki, S.

    1987-01-01

    Two forms of human thyroid peroxidase cDNAs were isolated from a λgt11 cDNA library, prepared from Graves disease thyroid tissue mRNA, by use of oligonucleotides. The longest complete cDNA, designated phTPO-1, has 3048 nucleotides and an open reading frame consisting of 933 amino acids, which would encode a protein with a molecular weight of 103,026. Five potential asparagine-linked glycosylation sites are found in the deduced amino acid sequence. The second peroxidase cDNA, designated phTPO-2, is almost identical to phTPO-1 beginning 605 base pairs downstream except that it contains 1-base-pair difference and lacks 171 base pairs in the middle of the sequence. This results in a loss of 57 amino acids corresponding to a molecular weight of 6282. Interestingly, this 171-nucleotide sequence has GT and AG at its 5' and 3' boundaries, respectively, that are in good agreement with donor and acceptor splice site consensus sequences. Using specific oligonucleotide probes for the mRNAs derived from the cDNA sequences hTOP-1 and hTOP-2, the authors show that both are expressed in all thyroid tissues examined and the relative level of two mRNAs is different in each sample. The results suggest that two thyroid peroxidase proteins might be generated through alternate splicing of the same gene. By using somatic cell hybrid lines, the thyroid peroxidase gene was mapped to the short arm of human chromosome 2

  4. A peroxidase-dependent apoplastic oxidative burst in cultured Arabidopsis cells functions in MAMP-elicited defense.

    Science.gov (United States)

    O'Brien, Jose A; Daudi, Arsalan; Finch, Paul; Butt, Vernon S; Whitelegge, Julian P; Souda, Puneet; Ausubel, Frederick M; Bolwell, G Paul

    2012-04-01

    Perception by plants of so-called microbe-associated molecular patterns (MAMPs) such as bacterial flagellin, referred to as pattern-triggered immunity, triggers a rapid transient accumulation of reactive oxygen species (ROS). We previously identified two cell wall peroxidases, PRX33 and PRX34, involved in apoplastic hydrogen peroxide (H2O2) production in Arabidopsis (Arabidopsis thaliana). Here, we describe the generation of Arabidopsis tissue culture lines in which the expression of PRX33 and PRX34 is knocked down by antisense expression of a heterologous French bean (Phaseolus vulgaris) peroxidase cDNA construct. Using these tissue culture lines and two inhibitors of ROS generation, azide and diphenylene iodonium, we found that perxoxidases generate about half of the H2O2 that accumulated in response to MAMP treatment and that NADPH oxidases and other sources such as mitochondria account for the remainder of the ROS. Knockdown of PRX33/PRX34 resulted in decreased expression of several MAMP-elicited genes, including MYB51, CYP79B2, and CYP81F2. Similarly, proteomic analysis showed that knockdown of PRX33/PRX34 led to the depletion of various MAMP-elicited defense-related proteins, including the two cysteine-rich peptides PDF2.2 and PDF2.3. Knockdown of PRX33/PRX34 also led to changes in the cell wall proteome, including increases in enzymes involved in cell wall remodeling, which may reflect enhanced cell wall expansion as a consequence of reduced H2O2-mediated cell wall cross-linking. Comparative metabolite profiling of a CaCl2 extract of the PRX33/PRX34 knockdown lines showed significant changes in amino acids, aldehydes, and keto acids but not fatty acids and sugars. Overall, these data suggest that PRX33/PRX34-generated ROS production is involved in the orchestration of pattern-triggered immunity in tissue culture cells.

  5. [Effect of extremely low frequency magnetic field on glutathione in rat muscles].

    Science.gov (United States)

    Ciejka, Elzbieta; Jakubowska, Ewa; Zelechowska, Paulina; Huk-Kolega, Halina; Kowalczyk, Agata; Goraca, Anna

    2014-01-01

    Free radicals (FR) are atoms, molecules or their fragments. Their excess leads to the development of oxidizing stress, the cause of many neoplastic, neurodegenerative and inflammatory diseases, and aging of the organism. Industrial pollution, tobacco smoke, ionizing radiation, ultrasound and magnetic field are the major FR exogenous sources. The low frequency magnetic field is still more commonly applied in the physical therapy. The aim of the presented study was to evaluate the effect of extremely low frequency magnetic field used in the magnetotherapy on the level of total glutathione, oxidized and reduced, and the redox state of the skeletal muscle cells, depending on the duration of exposure to magnetic field. The male rats, weight of 280-300 g, were randomly devided into 3 experimental groups: controls (group I) and treatment groups exposed to extremely low frequency magnetic field (ELF-MF) (group II exposed to 40 Hz, 7 mT for 0.5 h/day for 14 days and group III exposed to 40 Hz, 7 mT for 1 h/day for 14 days). Control rats were kept in a separate room not exposed to extremely low frequency magnetic field. Immediately after the last exposure, part of muscles was taken under pentobarbital anesthesia. Total glutathione, oxidized and reduced, and the redox state in the muscle tissue of animals were determined after exposure to magnetic fields. Exposure to low magnetic field: 40 Hz, 7 mT for 30 min/day and 60 min/day for 2 weeks significantly increased the total glutathione levels in the skeletal muscle compared to the control group (p magnetic therapy plays an important role in the development of adaptive mechanisms responsible for maintaining the oxidation-reduction balance in the body and depends on exposure duration.

  6. The involvement of oxidative stress in the mechanisms of damaging cadmium action in bone tissue: A study in a rat model of moderate and relatively high human exposure

    International Nuclear Information System (INIS)

    Brzoska, Malgorzata M.; Rogalska, Joanna; Kupraszewicz, Elzbieta

    2011-01-01

    It was investigated whether cadmium (Cd) may induce oxidative stress in the bone tissue in vivo and in this way contribute to skeleton damage. Total antioxidative status (TAS), antioxidative enzymes (glutathione peroxidase, superoxide dismutase, catalase), total oxidative status (TOS), hydrogen peroxide (H 2 O 2 ), lipid peroxides (LPO), total thiol groups (TSH) and protein carbonyl groups (PC) as well as Cd in the bone tissue at the distal femoral epiphysis and femoral diaphysis of the male rats that received drinking water containing 0, 5, or 50 mg Cd/l for 6 months were measured. Cd, depending on the level of exposure and bone location, decreased the bone antioxidative capacity and enhanced its oxidative status resulting in oxidative stress and oxidative protein and/or lipid modification. The treatment with 5 and 50 mg Cd/l decreased TAS and activities of antioxidative enzymes as well as increased TOS and concentrations of H 2 O 2 and PC at the distal femur. Moreover, at the higher exposure, the concentration of LPO increased and that of TSH decreased. The Cd-induced changes in the oxidative/antioxidative balance of the femoral diaphysis, abundant in cortical bone, were less advanced than at the distal femur, where trabecular bone predominates. The results provide evidence that, even moderate, exposure to Cd induces oxidative stress and oxidative modifications in the bone tissue. Numerous correlations noted between the indices of oxidative/antioxidative bone status, and Cd accumulation in the bone tissue as well as indices of bone turnover and bone mineral status, recently reported by us (Toxicology 2007, 237, 89-103) in these rats, allow for the hypothesis that oxidative stress is involved in the mechanisms of damaging Cd action in the skeleton. The paper is the first report from an in vivo study indicating that Cd may affect bone tissue through disorders in its oxidative/antioxidative balance resulting in oxidative stress.

  7. Immunocytochemical localisation of phloem lectin from Cucurbita maxima using peroxidase and colloidal-gold labels.

    Science.gov (United States)

    Smith, L M; Sabnis, D D; Johnson, R P

    1987-04-01

    Antibodies were raised against lectin purified from the sieve-tube exudate of Cucurbita maxima. Immunocytochemistry, using peroxidase-labelled antibodies and Protein A-colloidal gold, was employed to determine the location of the lectin within the tissues and cells of C. maxima and other cucurbit species. The anti-lectin antibodies bound to P-protein aggregates in sieve elements and companion cells, predominantly in the extrafascicular phloem of C. maxima. This may reflect the low rate of translocation in these cells. Under the electron microscope, the lectin was shown to be a component of P-protein filaments and was also found in association with the sieve-tube reticulum which lines the plasmalemma. The anti-lectin antibodies reacted with sieve-tube proteins from other species of the genus Cucurbita but showed only limited reaction with other genera. We suggest that the lectin serves to anchor P-protein filaments and associated proteins to the parietal layer of sieve elements.

  8. Targeting Glutathione-S Transferase Enzymes in Musculoskeletal Sarcomas: A Promising Therapeutic Strategy

    Directory of Open Access Journals (Sweden)

    Michela Pasello

    2011-01-01

    Full Text Available Recent studies have indicated that targeting glutathione-S-transferase (GST isoenzymes may be a promising novel strategy to improve the efficacy of conventional chemotherapy in the three most common musculoskeletal tumours: osteosarcoma, Ewing's sarcoma, and rhabdomyosarcoma. By using a panel of 15 drug-sensitive and drug-resistant human osteosarcoma, Ewing's sarcoma, and rhabdomyosarcoma cell lines, the efficay of the GST-targeting agent 6-(7-nitro-2,1,3-benzoxadiazol-4-ylthiohexanol (NBDHEX has been assessed and related to GST isoenzymes expression (namely GSTP1, GSTA1, GSTM1, and MGST. NBDHEX showed a relevant in vitro activity on all cell lines, including the drug-resistant ones and those with higher GSTs levels. The in vitro activity of NBDHEX was mostly related to cytostatic effects, with a less evident apoptotic induction. NBDHEX positively interacted with doxorubicin, vincristine, cisplatin but showed antagonistic effects with methotrexate. In vivo studies confirmed the cytostatic efficay of NBDHEX and its positive interaction with vincristine in Ewing's sarcoma cells, and also indicated a positive effect against the metastatisation of osteosarcoma cells. The whole body of evidence found in this study indicated that targeting GSTs in osteosarcoma, Ewing's sarcoma and rhabdomyosarcoma may be an interesting new therapeutic option, which can be considered for patients who are scarcely responsive to conventional regimens.

  9. Glutathione maintenance mitigates age-related susceptibility to redox cycling agents

    Directory of Open Access Journals (Sweden)

    Nicholas O. Thomas

    2016-12-01

    Full Text Available Isolated hepatocytes from young (4–6 mo and old (24–26 mo F344 rats were exposed to increasing concentrations of menadione, a vitamin K derivative and redox cycling agent, to determine whether the age-related decline in Nrf2-mediated detoxification defenses resulted in heightened susceptibility to xenobiotic insult. An LC50 for each age group was established, which showed that aging resulted in a nearly 2-fold increase in susceptibility to menadione (LC50 for young: 405 μM; LC50 for old: 275 μM. Examination of the known Nrf2-regulated pathways associated with menadione detoxification revealed, surprisingly, that NAD(PH: quinone oxido-reductase 1 (NQO1 protein levels and activity were induced 9-fold and 4-fold with age, respectively (p=0.0019 and p=0.018; N=3, but glutathione peroxidase 4 (GPX4 declined by 70% (p=0.0043; N=3. These results indicate toxicity may stem from vulnerability to lipid peroxidation instead of inadequate reduction of menadione semi-quinone. Lipid peroxidation was 2-fold higher, and GSH declined by a 3-fold greater margin in old versus young rat cells given 300 µM menadione (p2-fold reduction in cell death, suggesting that the age-related increase in menadione susceptibility likely stems from attenuated GSH-dependent defenses. This data identifies cellular targets for intervention in order to limit age-related toxicological insults to menadione and potentially other redox cycling compounds.

  10. The glutathione mimic ebselen inhibits oxidative stress but not endoplasmic reticulum stress in endothelial cells.

    Science.gov (United States)

    Ahwach, Salma Makhoul; Thomas, Melanie; Onstead-Haas, Luisa; Mooradian, Arshag D; Haas, Michael J

    2015-08-01

    Reactive oxygen species are associated with cardiovascular disease, diabetes, and atherosclerosis, yet the use of antioxidants in clinical trials has been ineffective at improving outcomes. In endothelial cells, high-dextrose-induced oxidative stress and endoplasmic reticulum stress promote endothelial dysfunction leading to the recruitment and activation of peripheral blood lymphocytes and the breakdown of barrier function. Ebselen, a glutathione peroxidase 1 (GPX1) mimic, has been shown to improve β-cell function in diabetes and prevent atherosclerosis. To determine if ebselen inhibits both oxidative stress and endoplasmic reticulum (ER) stress in endothelial cells, we examined its effects in human umbilical vein endothelial cells (HUVEC) and human coronary artery endothelial cells (HCAEC) with and without high-dextrose. Oxidative stress and ER stress were measured by 2-methyl-6-(4-methoxyphenyl)-3,7-dihydroimidazo[1,2-A]pyrazin-3-one hydrochloride chemiluminescence and ER stress alkaline phosphatase assays, respectively. GPX1 over-expression and knockdown were performed by transfecting cells with a GPX1 expression construct or a GPX1-specific siRNA, respectively. Ebselen inhibited dextrose-induced oxidative stress but not ER stress in both HUVEC and HCAEC. Ebselen also had no effect on tunicamycin-induced ER stress in HCAEC. Furthermore, augmentation of GPX1 activity directly by sodium selenite supplementation or transfection of a GPX1 expression plasmid decreased dextrose-induced oxidative stress but not ER stress, while GPX1 knockout enhanced oxidative stress but had no effect on ER stress. These results suggest that ebselen targets only oxidative stress but not ER stress. Copyright © 2015. Published by Elsevier Inc.

  11. In Vivo Monitoring of pH, Redox Status, and Glutathione Using L-Band EPR for Assessment of Therapeutic Effectiveness in Solid Tumors

    Science.gov (United States)

    Bobko, Andrey A.; Eubank, Timothy D.; Voorhees, Jeffrey L.; Efimova, Olga V.; Kirilyuk, Igor A.; Petryakov, Sergey; Trofimiov, Dmitrii G.; Marsh, Clay B.; Zweier, Jay L.; Grigor’ev, Igor A.; Samouilov, Alexandre; Khramtsov, Valery V.

    2011-01-01

    Approach for in vivo real-time assessment of tumor tissue extracellular pH (pHe), redox, and intracellular glutathione based on L-band EPR spectroscopy using dual function pH and redox nitroxide probe and disulfide nitroxide biradical, is described. These parameters were monitored in PyMT mice bearing breast cancer tumors during treatment with granulocyte macrophage colony-stimulating factor. It was observed that tumor pHe is about 0.4 pH units lower than that in normal mammary gland tissue. Treatment with granulocyte macrophage colony-stimulating factor decreased the value of pHe by 0.3 units compared with PBS control treatment. Tumor tissue reducing capacity and intracellular glutathione were elevated compared with normal mammary gland tissue. Granulocyte macrophage colony-stimulating factor treatment resulted in a decrease of the tumor tissue reducing capacity and intracellular glutathione content. In addition to spectroscopic studies, pHe mapping was performed using recently proposed variable frequency proton–electron double-resonance imaging. The pH mapping superimposed with MRI image supports probe localization in mammary gland/tumor tissue, shows high heterogeneity of tumor tissue pHe and a difference of about 0.4 pH units between average pHe values in tumor and normal mammary gland. In summary, the developed multifunctional approach allows for in vivo, noninvasive pHe, extracellular redox, and intracellular glutathione content monitoring during investigation of various therapeutic strategies for solid tumors. Magn Reson Med 000:000–000, 2011. PMID:22113626

  12. Potential involvement of oxygen intermediates and glutathione depletion in UV-induced epidermal cell injury in vitro

    International Nuclear Information System (INIS)

    Hsieh, G.C.; Acosta, D.

    1991-01-01

    Generation of reactive oxygen species (ROS) and depletion of glutathione (GSH) are suggested as the cytotoxic mechanisms for UVB-induced cellular damage. Primary monolayer cultures of epidermal keratinocytes (KCs) prepared from the skin of neonatal rats were irradiated with UVB at levels of 0.25-3.0 J/cm 2 . Cytotoxicity was measured at 3, 6, and 12 hr after UVB radiation. Exposure of KCs to UVB resulted in time- and dose-related toxic responses as determined by plasma membrane integrity, lysosomal function and mitochondrial metabolic activity. Irradiated KCs generated superoxide in a dose-dependent manner when compared to sham-irradiated cells. Superoxide formation, which occurred before and concomitant with cell injury, was decreased by superoxide dismutase (SOD). Cell injury was also significantly prevented by ROS scavengers, SOD and catalase. Pretreatment of cells with endocytosis inhibitors, cytochalasin B and methylamine, suppressed the ability of SOD and catalase to protect keratinocytes from UVB-induced toxicity. Irradiation of cells with UVB caused rapid depletion of GSH to about 30% of unirradiated levels within 15 min. UVB-irradiation led to a rapid transient increase in GSH peroxidase activity, concomitant with a marked decrease in the GSH/GSSG ratio. After 1 hr., while the GSH/GSSG ratio remained low, the GSH peroxidase activity declined below the control levels in UVB-treated epidermal cells. Following extensive GSH depletion in cells preincubated with 0.1 mM buthiomine sulfoximine, KCs became strongly sensitized to the cytotoxic action of UVB. These results indicate that UVB-induced cell injury in cultured KCs may be mediated by ROs and that endogenous GSH may play an important protective role against the cytotoxic action of UVB

  13. A putative peroxidase cDNA from turnip and analysis of the encoded protein sequence.

    Science.gov (United States)

    Romero-Gómez, S; Duarte-Vázquez, M A; García-Almendárez, B E; Mayorga-Martínez, L; Cervantes-Avilés, O; Regalado, C

    2008-12-01

    A putative peroxidase cDNA was isolated from turnip roots (Brassica napus L. var. purple top white globe) by reverse transcriptase-polymerase chain reaction (RT-PCR) and rapid amplification of cDNA ends (RACE). Total RNA extracted from mature turnip roots was used as a template for RT-PCR, using a degenerated primer designed to amplify the highly conserved distal motif of plant peroxidases. The resulting partial sequence was used to design the rest of the specific primers for 5' and 3' RACE. Two cDNA fragments were purified, sequenced, and aligned with the partial sequence from RT-PCR, and a complete overlapping sequence was obtained and labeled as BbPA (Genbank Accession No. AY423440, named as podC). The full length cDNA is 1167bp long and contains a 1077bp open reading frame (ORF) encoding a 358 deduced amino acid peroxidase polypeptide. The putative peroxidase (BnPA) showed a calculated Mr of 34kDa, and isoelectric point (pI) of 4.5, with no significant identity with other reported turnip peroxidases. Sequence alignment showed that only three peroxidases have a significant identity with BnPA namely AtP29a (84%), and AtPA2 (81%) from Arabidopsis thaliana, and HRPA2 (82%) from horseradish (Armoracia rusticana). Work is in progress to clone this gene into an adequate host to study the specific role and possible biotechnological applications of this alternative peroxidase source.

  14. Comparative study of biological activity of glutathione, sodium ...

    African Journals Online (AJOL)

    Glutathione (GSH) and sodium tungstate (Na2WO4) are important pharmacological agents. They provide protection to cells against cytotoxic agents and thus reduce their cytotoxicity. It was of interest to study the biological activity of these two pharmacological active agents. Different strains of bacteria were used and the ...

  15. Glutathione dysregulation and the etiology and progression of human diseases.

    NARCIS (Netherlands)

    Ballatori, N.; Krance, S.M.; Notenboom, S.; Shi, S.; Tieu, K.; Hammond, C.L.

    2009-01-01

    Glutathione (GSH) plays an important role in a multitude of cellular processes, including cell differentiation, proliferation, and apoptosis, and as a result, disturbances in GSH homeostasis are implicated in the etiology and/or progression of a number of human diseases, including cancer, diseases

  16. Metabolic modulation of glutathione in whole blood components ...

    African Journals Online (AJOL)

    use

    2011-12-05

    Dec 5, 2011 ... Key words: Lead acetate, glutathione (GSH), dithiobisdinitrobenzoic acid (DTNB), plasma and cytosolic ... fraction. Control containing 1 ml of venous blood and 1 ml of 0.9%. NaCl solution was also centrifuged for isolation of plasma. The packed cells were .... altered fatty acid composition of membranes?

  17. Is Glutathione the Major Cellular Target of Cisplatin?

    DEFF Research Database (Denmark)

    Kasherman, Yonit; Stürup, Stefan; gibson, dan

    2009-01-01

    Cisplatin is an anticancer drug whose efficacy is limited because tumors develop resistance to the drug. Resistant cells often have elevated levels of cellular glutathione (GSH), believed to be the major cellular target of cisplatin that inactivates the drug by binding to it irreversibly, forming...

  18. A novel method for screening the glutathione transferase inhibitors

    Directory of Open Access Journals (Sweden)

    Węgrzyn Grzegorz

    2009-03-01

    Full Text Available Abstract Background Glutathione transferases (GSTs belong to the family of Phase II detoxification enzymes. GSTs catalyze the conjugation of glutathione to different endogenous and exogenous electrophilic compounds. Over-expression of GSTs was demonstrated in a number of different human cancer cells. It has been found that the resistance to many anticancer chemotherapeutics is directly correlated with the over-expression of GSTs. Therefore, it appears to be important to find new GST inhibitors to prevent the resistance of cells to anticancer drugs. In order to search for glutathione transferase (GST inhibitors, a novel method was designed. Results Our results showed that two fragments of GST, named F1 peptide (GYWKIKGLV and F2 peptide (KWRNKKFELGLEFPNL, can significantly inhibit the GST activity. When these two fragments were compared with several known potent GST inhibitors, the order of inhibition efficiency (measured in reactions with 2,4-dinitrochlorobenzene (CDNB and glutathione as substrates was determined as follows: tannic acid > cibacron blue > F2 peptide > hematin > F1 peptide > ethacrynic acid. Moreover, the F1 peptide appeared to be a noncompetitive inhibitor of the GST-catalyzed reaction, while the F2 peptide was determined as a competitive inhibitor of this reaction. Conclusion It appears that the F2 peptide can be used as a new potent specific GST inhibitor. It is proposed that the novel method, described in this report, might be useful for screening the inhibitors of not only GST but also other enzymes.

  19. Insecticide resistance and glutathione S-transferases in mosquitoes ...

    African Journals Online (AJOL)

    Mosquito glutathione S-transferases (GSTs) have received considerable attention in the last 20 years because of their role in insecticide metabolism producing resistance. Many different compounds, including toxic xenobiotics and reactive products of intracellular processes such as lipid peroxidation, act as GST substrates.

  20. State of the glutathione system at different periods after irradiation

    International Nuclear Information System (INIS)

    Petushok, N.; Trebukhina, R.

    1997-01-01

    The effect of the 3-fold irradiation on the glutatione system was studied. Activation of these system was shown to take place at early terms (1 hour) after irradiation, then it was exhausted that resulted in accumulation of lipid peroxidation products in blood. This phase changes in glutathione system could be correspond to certain stages of stress-syndrome. (author)

  1. Oxidative Stress Markers and Genetic Polymorphisms of Glutathione ...

    African Journals Online (AJOL)

    Hence, we evaluated the serum levels of oxidative stress markers and investigated genetic polymorphisms of glutathione S-transferase associated with autism. Materials and Methods: Forty-two children clinically diagnosed with ASD using the Diagnostic and Statistical Manual for Mental Disorders (DSM-5) criteria and a ...

  2. Mechanism-based biomarker gene sets for glutathione depletion-related hepatotoxicity in rats

    International Nuclear Information System (INIS)

    Gao Weihua; Mizukawa, Yumiko; Nakatsu, Noriyuki; Minowa, Yosuke; Yamada, Hiroshi; Ohno, Yasuo; Urushidani, Tetsuro

    2010-01-01

    Chemical-induced glutathione depletion is thought to be caused by two types of toxicological mechanisms: PHO-type glutathione depletion [glutathione conjugated with chemicals such as phorone (PHO) or diethyl maleate (DEM)], and BSO-type glutathione depletion [i.e., glutathione synthesis inhibited by chemicals such as L-buthionine-sulfoximine (BSO)]. In order to identify mechanism-based biomarker gene sets for glutathione depletion in rat liver, male SD rats were treated with various chemicals including PHO (40, 120 and 400 mg/kg), DEM (80, 240 and 800 mg/kg), BSO (150, 450 and 1500 mg/kg), and bromobenzene (BBZ, 10, 100 and 300 mg/kg). Liver samples were taken 3, 6, 9 and 24 h after administration and examined for hepatic glutathione content, physiological and pathological changes, and gene expression changes using Affymetrix GeneChip Arrays. To identify differentially expressed probe sets in response to glutathione depletion, we focused on the following two courses of events for the two types of mechanisms of glutathione depletion: a) gene expression changes occurring simultaneously in response to glutathione depletion, and b) gene expression changes after glutathione was depleted. The gene expression profiles of the identified probe sets for the two types of glutathione depletion differed markedly at times during and after glutathione depletion, whereas Srxn1 was markedly increased for both types as glutathione was depleted, suggesting that Srxn1 is a key molecule in oxidative stress related to glutathione. The extracted probe sets were refined and verified using various compounds including 13 additional positive or negative compounds, and they established two useful marker sets. One contained three probe sets (Akr7a3, Trib3 and Gstp1) that could detect conjugation-type glutathione depletors any time within 24 h after dosing, and the other contained 14 probe sets that could detect glutathione depletors by any mechanism. These two sets, with appropriate scoring

  3. Thyroid Peroxidase Antibody and Screening for Postpartum Thyroid Dysfunction

    Directory of Open Access Journals (Sweden)

    Mohamed A. Adlan

    2011-01-01

    Full Text Available Postpartum thyroid dysfunction (PPTD is a common disorder which causes considerable morbidity in affected women. The availability of effective treatment for hypothyroid PPTD, the occurrence of the disease in subsequent pregnancies and the need to identify subjects who develop long term hypothyroidism, has prompted discussion about screening for this disorder. There is currently no consensus about screening as investigations hitherto have been variable in their design, definitions and assay frequency and methodology. There is also a lack of consensus about a suitable screening tool although thyroid peroxidase antibody (TPOAb is a leading contender. We present data about the use of TPOAb in early pregnancy and its value as a screening tool. Although its positive predictive value is moderate, its sensitivity and specificity when used in early pregnancy are comparable or better compared to other times during pregnancy and the postpartum period. Recent studies have also confirmed this strategy to be cost effective and to compare favourably with other screening strategies. We also explore the advantages of universal screening.

  4. Colorimetric peroxidase mimetic assay for uranyl detection in sea water

    KAUST Repository

    Zhang, Dingyuan

    2015-03-04

    Uranyl (UO2 2+) is a form of uranium in aqueous solution that represents the greatest risk to human health because of its bioavailability. Different sensing techniques have been used with very sensitive detection limits especially the recently reported uranyl-specific DNAzymes systems. However, to the best of our knowledge, few efficient detection methods have been reported for uranyl sensing in seawater. Herein, gold nanoclusters (AuNCs) are employed in an efficient spectroscopic method to detect uranyl ion (UO2 2+) with a detection limit of 1.86 ÎM. In the absence of UO2 2+, the BSA-stabilized AuNCs (BSA-AuNCs) showed an intrinsic peroxidase-like activity. In the presence of UO2 2+, this activity can be efficiently restrained. The preliminary quenching mechanism and selectivity of UO2 2+ was also investigated and compared with other ions. This design strategy could be useful in understanding the binding affinity of protein-stabilized AuNCs to UO2 2+ and consequently prompt the recycling of UO2 2+ from seawater.

  5. Silica Sol-Gel Entrapment of the Enzyme Chloro peroxidase

    International Nuclear Information System (INIS)

    Le, T.; Chan, S.; Ebaid, B.; Sommerhalter, M.

    2015-01-01

    The enzyme chloro peroxidase (CPO) was immobilized in silica sol-gel beads prepared from tetramethoxysilane. The average pore diameter of the silica host structure (∼3 nm) was smaller than the globular CPO diameter (∼6 nm) and the enzyme remained entrapped after sol-gel maturation. The catalytic performance of the entrapped enzyme was assessed via the pyrogallol peroxidation reaction. Sol-gel beads loaded with 4 μg CPO per mL sol solution reached 9-12% relative activity compared to free CPO in solution. Enzyme kinetic analysis revealed a decrease in K_cat but no changes in K_M or K_I . Product release or enzyme damage might thus limit catalytic performance. Yet circular dichroism and visible absorption spectra of transparent CPO sol-gel sheets did not indicate enzyme damage. Activity decline due to methanol exposure was shown to be reversible in solution. To improve catalytic performance the sol-gel protocol was modified. The incorporation of 5, 20, or 40% methyltrimethoxysilane resulted in more brittle sol-gel beads but the catalytic performance increased to 14% relative to free CPO in solution. The use of more acidic casting buffers (ph 4.5 or 5.5 instead of 6.5) resulted in a more porous silica host reaching up to 18% relative activity

  6. Biotechnological advances towards an enhanced peroxidase production in Pichia pastoris.

    Science.gov (United States)

    Krainer, Florian W; Gerstmann, Michaela A; Darnhofer, Barbara; Birner-Gruenberger, Ruth; Glieder, Anton

    2016-09-10

    Horseradish peroxidase (HRP) is a high-demand enzyme for applications in diagnostics, bioremediation, biocatalysis and medicine. Current HRP preparations are isolated from horseradish roots as mixtures of biochemically diverse isoenzymes. Thus, there is a strong need for a recombinant production process enabling a steady supply with enzyme preparations of consistent high quality. However, most current recombinant production systems are limited at titers in the low mg/L range. In this study, we used the well-known yeast Pichia pastoris as host for recombinant HRP production. To enhance recombinant enzyme titers we systematically evaluated engineering approaches on the secretion process, coproduction of helper proteins, and compared expression from the strong methanol-inducible PAOX1 promoter, the strong constitutive PGAP promoter, and a novel bidirectional promoter PHTX1. Ultimately, coproduction of HRP and active Hac1 under PHTX1 control yielded a recombinant HRP titer of 132mg/L after 56h of cultivation in a methanol-independent and easy-to-do bioreactor cultivation process. With regard to the many versatile applications for HRP, the establishment of a microbial host system suitable for efficient recombinant HRP production was highly overdue. The novel HRP production platform in P. pastoris presented in this study sets a new benchmark for this medically relevant enzyme. Copyright © 2016 The Authors. Published by Elsevier B.V. All rights reserved.

  7. Thermal and high pressure inactivation kinetics of blueberry peroxidase.

    Science.gov (United States)

    Terefe, Netsanet Shiferaw; Delon, Antoine; Versteeg, Cornelis

    2017-10-01

    This study for the first time investigated the stability and inactivation kinetics of blueberry peroxidase in model systems (McIlvaine buffer, pH=3.6, the typical pH of blueberry juice) during thermal (40-80°C) and combined high pressure-thermal processing (0.1-690MPa, 30-90°C). At 70-80°C, the thermal inactivation kinetics was best described by a biphasic model with ∼61% labile and ∼39% stable fractions at temperature between 70 and 75°C. High pressure inhibited the inactivation of the enzyme with no inactivation at pressures as high as 690MPa and temperatures less than 50°C. The inactivation kinetics of the enzyme at 60-70°C, and pressures higher than 500MPa was best described by a first order biphasic model with ∼25% labile fraction and 75% stable fraction. The activation energy values at atmospheric pressure were 548.6kJ/mol and 324.5kJ/mol respectively for the stable and the labile fractions. Crown Copyright © 2017. Published by Elsevier Ltd. All rights reserved.

  8. Identification and characterisation of multiple glutathione S-transferase genes from the diamondback moth, Plutella xylostella.

    Science.gov (United States)

    Chen, Xi'en; Zhang, Ya-lin

    2015-04-01

    The diamondback moth (DBM), Plutella xylostella, is one of the most harmful insect pests on crucifer crops worldwide. In this study, 19 cDNAs encoding glutathione S-transferases (GSTs) were identified from the genomic and transcriptomic database for DBM (KONAGAbase) and further characterized. Phylogenetic analysis showed that the 19 GSTs were classified into six different cytosolic classes, including four in delta, six in epsilon, three in omega, two in sigma, one in theta and one in zeta. Two GSTs were unclassified. RT-PCR analysis revealed that most GST genes were expressed in all developmental stages, with higher expression in the larval stages. Six DBM GSTs were expressed at the highest levels in the midgut tissue. Twelve purified recombinant GSTs showed varied enzymatic properties towards 1-chloro-2,4-dinitrobenzene and glutathione, whereas rPxGSTo2, rPxGSTz1 and rPxGSTu2 had no activity. Real-time quantitative PCR revealed that expression levels of the 19 DBM GST genes were varied and changed after exposure to acephate, indoxacarb, beta-cypermethrin and spinosad. PxGSTd3 was significantly overexpressed, while PxGSTe3 and PxGSTs2 were significantly downregulated by all four insecticide exposures. The changes in DBM GST gene expression levels exposed to different insecticides indicate that they may play individual roles in tolerance to insecticides and xenobiotics. © 2014 Society of Chemical Industry.

  9. Nitric Oxide Ameliorates Zinc Oxide Nanoparticles Phytotoxicity in Wheat Seedlings: Implication of the Ascorbate–Glutathione Cycle

    Science.gov (United States)

    Tripathi, Durgesh K.; Mishra, Rohit K.; Singh, Swati; Singh, Samiksha; Vishwakarma, Kanchan; Sharma, Shivesh; Singh, Vijay P.; Singh, Prashant K.; Prasad, Sheo M.; Dubey, Nawal K.; Pandey, Avinash C.; Sahi, Shivendra; Chauhan, Devendra K.

    2017-01-01

    The present study investigates ameliorative effects of nitric oxide (NO) against zinc oxide nanoparticles (ZnONPs) phytotoxicity in wheat seedlings. ZnONPs exposure hampered growth of wheat seedlings, which coincided with reduced photosynthetic efficiency (Fv/Fm and qP), due to increased accumulation of zinc (Zn) in xylem and phloem saps. However, SNP supplementation partially mitigated the ZnONPs-mediated toxicity through the modulation of photosynthetic activity and Zn accumulation in xylem and phloem saps. Further, the results reveal that ZnONPs treatments enhanced levels of hydrogen peroxide and lipid peroxidation (as malondialdehyde; MDA) due to severely inhibited activities of the following ascorbate–glutatione cycle (AsA–GSH) enzymes: ascorbate peroxidase, glutathione reductase, monodehydroascorbate reductase and dehydroascorbate reductase, and its associated metabolites ascorbate and glutathione. In contrast to this, the addition of SNP together with ZnONPs maintained the cellular functioning of the AsA–GSH cycle properly, hence lesser damage was noticed in comparison to ZnONPs treatments alone. The protective effect of SNP against ZnONPs toxicity on fresh weight (growth) can be reversed by 2-(4carboxy-2-phenyl)-4,4,5,5-tetramethyl- imidazoline-1-oxyl-3-oxide, a NO scavenger, and thus suggesting that NO released from SNP ameliorates ZnONPs toxicity. Overall, the results of the present study have shown the role of NO in the reducing of ZnONPs toxicity through the regulation of accumulation of Zn as well as the functioning of the AsA–GSH cycle. PMID:28220127

  10. Phylogenetic characterization of Clonorchis sinensis proteins homologous to the sigma-class glutathione transferase and their differential expression profiles.

    Science.gov (United States)

    Bae, Young-An; Kim, Jeong-Geun; Kong, Yoon

    2016-01-01

    Glutathione transferase (GST) is one of the major antioxidant proteins with diverse supplemental activities including peroxidase, isomerase, and thiol transferase. GSTs are classified into multiple classes on the basis of their primary structures and substrate/inhibitor specificity. However, the evolutionary routes and physiological environments specific to each of the closely related bioactive enzymes remain elusive. The sigma-like GSTs exhibit amino acid conservation patterns similar to the prostaglandin D synthases (PGDSs). In this study, we analyzed the phylogenetic position of the GSTs of the biocarcinogenic liver fluke, Clonorchis sinensis. We also observed induction profile of the GSTs in association with the parasite's maturation and in response to exogenous oxidative stresses, with special attention to sigma-class GSTs and PGDSs. The C. sinensis genome encoded 12 GST protein species, which were separately assigned to cytosolic (two omega-, one zeta-, two mu-, and five sigma-class), mitochondrial (one kappa-class), and microsomal (one membrane-associated proteins in eicosanoid and glutathione metabolism-like protein) GST families. Multiple sigma GST (or PGDS) orthologs were also detected in Opisthorchis viverrini. Other trematode species possessed only a single sigma-like GST gene. A phylogenetic analysis demonstrated that one of the sigma GST lineages duplicated in the common ancestor of trematodes were specifically expanded in the opisthorchiids, but deleted in other trematodes. The induction profiles of these sigma GST genes along with the development and aging of C. sinensis, and against various exogenous chemical stimuli strongly suggest that the paralogous sigma GST genes might be undergone specialized evolution to cope with the diverse hostile biochemical environments within the mammalian hepatobiliary ductal system. Copyright © 2016 Elsevier B.V. All rights reserved.

  11. In vitro antileishmanial activity of fisetin flavonoid via inhibition of glutathione biosynthesis and arginase activity in Leishmania infantum.

    Science.gov (United States)

    Adinehbeigi, Keivan; Razi Jalali, Mohammad Hossein; Shahriari, Ali; Bahrami, Somayeh

    2017-06-01

    With the increasing emergence of drug resistant Leishmania sp. in recent years, combination therapy has been considered as a useful way to treat and control of Leishmaniasis. The present study was designed to evaluate the antileishmanial effects of the fisetin alone and combination of fisetin plus Meglumine antimoniate (Fi-MA) against Leishmania infantum. The IC50 values for fisetin were obtained 0.283 and 0.102 μM against promastigotes and amastigote forms, respectively. Meglumine antimoniate (MA, Glucantime) as control drug also revealed IC50 values of 0.247 and 0.105 μM for promastigotes and amastigotes of L. infantum, respectively. In order to determine the mode of action of fisetin and Meglumine antimoniate (MA, Glucantime), the activities of arginase (ARG), catalase (CAT), glutathione peroxidase (GPx) and superoxide dismutase (SOD) were measured. Moreover, intracellular glutathione (GSH) and nitric oxide (NO) levels in L. infantum-infected macrophages and L. infantum promastigotes which were treated with IC50 concentrations of fisetin, MA and Fi-MA were investigated. Our results showed that MA decreased CAT and SOD activity and increased NO levels in L. infantum-infected macrophages. In promastigotes, MA inhibited parasite SOD activity and reduced parasite NO production. The decreased levels of most of the antioxidant enzymes, accompanying by the raised level of NO in treated macrophages with MA, were observed to regain their normal profiles due to Fi-MA treatment. Furthermore, fisetin could prevent the growth of promastigotes by inhibition of ARG activity and reduction of GSH levels and NO production. In conclusion, these findings showed that fisetin improves MA side effects.

  12. Contribution of Arginine 13 to the Catalytic Activity of Human Class Pi Glutathione Transferase P1-1

    International Nuclear Information System (INIS)

    Kong, Ji Na; Jo, Dong Hyeon; Do, Hyun Dong; Lee, Jin Ju; Kong, Kwang Hoon

    2010-01-01

    Arg13 is a conserved active-site residue in all known Pi class glutathione S-transferases (GSTs) and in most Alpha class GSTs. To evaluate its contribution to substrate binding and catalysis of this residue, three mutants (R13A, R13K, and R13L) were expressed in Escherichia coli and purified by GSH affinity chromatography. The substitutions of Arg13 significantly affected GSH-conjugation activity, while scarcely affecting glutathione peroxidase or steroid isomerase activities. Mutation of Arg13 into Ala largely reduced the GSH-conjugation activity by approximately 85 - 95%, whereas substitutions by Lys and Leu barely affected activity. These results suggest that, in the GSH-conjugation activity of hGST P1-1, the contribution of Arg13 toward catalytic activity is highly dependent on substrate specificities and the size of the side chain at position 13. From the kinetic parameters, introduction of larger side chains at position 13 results in stronger affinity (Leu > Lys, Arg > Ala) towards GSH. The substitutions of Arg13 with alanine and leucine significantly affected k cat , whereas substitution with Lys was similar to that of the wild type, indicating the significance of a positively charged residue at position 13. From the plots of log (k cat /K m CDNB ) against pH, the pK a values of the thiol group of GSH bound in R13A, R13K, and R13L were estimated to be 1.8, 1.4, and 1.8 pK units higher than the pK a value of the wildtype enzyme, demonstrating the contribution of the Arg13 guanidinium group to the electrostatic field in the active site. From these results, we suggest that contribution of Arg13 in substrate binding is highly dependent on the nature of the electrophilic substrates, while in the catalytic mechanism, it stabilizes the GSH thiolate through hydrogen bonding

  13. Multiscale modelling approach combining a kinetic model of glutathione metabolism with PBPK models of paracetamol and the potential glutathione-depletion biomarkes ophthalmic acid and 5-oxoproline in humans and rats

    NARCIS (Netherlands)

    Geenen, S.; Yates, J.W.T.; Kenna, J.G.; Bois, F.Y.; Wilson, I.D.; Westerhoff, H.V.

    2014-01-01

    A key role of the antioxidant glutathione is detoxification of chemically reactive electrophilic drug metabolites within the liver. Therefore glutathione depletion can have severe toxic consequences. Ophthalmic acid and 5-oxoproline are metabolites involved in glutathione metabolism, which can be

  14. Glutathione reductase: solvent equilibrium and kinetic isotope effects

    International Nuclear Information System (INIS)

    Wong, K.K.; Vanoni, M.A.; Blanchard, J.S.

    1988-01-01

    Glutathione reductase catalyzes the NADPH-dependent reduction of oxidized glutathione (GSSG). The kinetic mechanism is ping-pong, and we have investigated the rate-limiting nature of proton-transfer steps in the reactions catalyzed by the spinach, yeast, and human erythrocyte glutathione reductases using a combination of alternate substrate and solvent kinetic isotope effects. With NADPH or GSSG as the variable substrate, at a fixed, saturating concentration of the other substrate, solvent kinetic isotope effects were observed on V but not V/K. Plots of Vm vs mole fraction of D 2 O (proton inventories) were linear in both cases for the yeast, spinach, and human erythrocyte enzymes. When solvent kinetic isotope effect studies were performed with DTNB instead of GSSG as an alternate substrate, a solvent kinetic isotope effect of 1.0 was observed. Solvent kinetic isotope effect measurements were also performed on the asymmetric disulfides GSSNB and GSSNP by using human erythrocyte glutathione reductase. The Km values for GSSNB and GSSNP were 70 microM and 13 microM, respectively, and V values were 62 and 57% of the one calculated for GSSG, respectively. Both of these substrates yield solvent kinetic isotope effects greater than 1.0 on both V and V/K and linear proton inventories, indicating that a single proton-transfer step is still rate limiting. These data are discussed in relationship to the chemical mechanism of GSSG reduction and the identity of the proton-transfer step whose rate is sensitive to solvent isotopic composition. Finally, the solvent equilibrium isotope effect measured with yeast glutathione reductase is 4.98, which allows us to calculate a fractionation factor for the thiol moiety of GSH of 0.456

  15. Inhibition of Heme Peroxidase During Phenol Derivatives Oxidation. Possible Molecular Cloaking of the Active Center

    Directory of Open Access Journals (Sweden)

    Juozas Kulys

    2005-10-01

    Full Text Available Abstract: Ab initio quantum chemical calculations have been applied to the study of the molecular structure of phenol derivatives and oligomers produced during peroxidasecatalyzed oxidation. The interaction of substrates and oligomers with Arthromyces ramosus peroxidase was analyzed by docking methods. The most possible interaction site of oligomers is an active center of the peroxidase. The complexation energy increases with increasing oligomer length. However, the complexed oligomers do not form a precise (for the reaction hydrogen bonding network in the active center of the enzyme. It seems likely that strong but non productive docking of the oligomers determines peroxidase inhibition during the reaction.

  16. Permeability of skin and oral mucosa to water and horseradish peroxidase as related to the thickness of the permeability barrier

    International Nuclear Information System (INIS)

    Squier, C.A.; Hall, B.K.

    1985-01-01

    The permeability of porcine skin and keratinized and nonkeratinized oral mucosa to tritium-labeled water and horseradish peroxidase (HRPO) was determined using perfusion chambers. Small blocks from each tissue were also incubated with HRPO and the extent of penetration visualized microscopically; this enabled measurements to be made of the thickness of the permeability barrier to this water-soluble tracer. Results obtained after inverting the oral mucosa in the chambers or adding metabolic inhibitors indicated that both compounds diffuse across the tissue. The permeability constants derived directly in the study showed that skin was less permeable than oral mucosa and that the floor of the mouth was significantly more permeable than all other regions. When these constants were normalized in terms of a standard permeability barrier thickness and the different tissues compared, the values obtained for skin were again less than those of the oral regions but, of these, the buccal mucosa was significantly higher. The difference in permeability between epidermis and keratinized oral epithelium may be due to differences in the volume density of membrane-coating granules known to exist between the tissues; differences between the oral mucosal regions may reflect differences in the nature of the intercellular barrier material

  17. ISOENZYMATIC POLYMORPHISM AND ACTIVITY OF PEROXIDASES OF COMMON BEAN (Phaseolus vulgaris L. UNDER SALINE STRESS

    Directory of Open Access Journals (Sweden)

    F. BROETTO

    1997-09-01

    Full Text Available One of the uses of the technique of tissue culture for plant breeding is the identification of cell lines tolerant to salt stress.In order to study the biochemical mechanisms involved in the genetic expression to salt tolerance, callus from embryo axis of four bean cultivars (cv. IAC-carioca; cv. IAPAR-14; cv. JALO-EEP558; CV. BAT-93 were grown in Murashige & Skoog (1962 medium, supplemented with NaCl in the concentrations of 0, 20, 40, 60 and 80 mM. After 14 days callus were harvested and analyzed according to their isoenzymatic patterns and peroxidase activities. BAT and IAPAR cultivars showed two common activity zones in the anodic region, with only one specific enzymatic band to each one (the two fastest migration band; it is possible that the two middle anodic zones detected are products of the same enzymatic locus but from different alleles with different eletrophoretic mobilities. Cv. JALO showed two anodic activities in common with cvs IAC and IAPAR with an exclusive anodic zone of slower migration which showed the most intense activity of all cultivars analyzed. This cv. still showed a dimeric heterozygotic catodic zone in all treated samples. Probably this is the same zone which occurs in homozygosis with fixation of the slower allele for all cvs BAT and IAPAR