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Sample records for antioxidant response element

  1. A genomic screen for activators of the antioxidant response element

    PubMed Central

    Liu, Yanxia; Kern, Jonathan T.; Walker, John R.; Johnson, Jeffrey A.; Schultz, Peter G.; Luesch, Hendrik

    2007-01-01

    The antioxidant response element (ARE) is a cis-acting regulatory enhancer element found in the 5′ flanking region of many phase II detoxification enzymes. Up-regulation of ARE-dependent target genes is known to have neuroprotective effects; yet, the mechanism of activation is largely unknown. By screening an arrayed collection of ≈15,000 full-length expression cDNAs in the human neuroblastoma cell line IMR-32 with an ARE-luciferase reporter, we have identified several cDNAs not previously associated with ARE activation. A subset of cDNAs, encoding sequestosome 1 (SQSTM1) and dipeptidylpeptidase 3 (DPP3), activated the ARE in primary mouse-derived cortical neurons. Overexpression of SQSTM1 and DPP3 in IMR-32 cells stimulated NF-E2-related factor 2 (NRF2) nuclear translocation and led to increased levels of NAD(P)H:quinone oxidoreductase 1, a protein which is transcriptionally regulated by the ARE. When transfected into IMR-32 neuroblastoma cells that were depleted of transcription factor NRF2 by RNA interference, SQSTM1 and DPP3 were unable to activate the ARE or induce NAD(P)H:quinone oxidoreductase 1 expression, indicating that the ARE activation upon ectopic expression of these cDNAs is mediated by NRF2. Studies with pharmacological inhibitors indicated that 1-phosphatidylinositol 3-kinase and protein kinase C signaling are essential for activity. Overexpression of these cDNAs conferred partial resistance to hydrogen peroxide or rotenone-induced toxicity, consistent with the induction of antioxidant and phase II detoxification enzymes, which can protect from oxidative stress. This work and other such studies may provide mechanisms for activating the ARE in the absence of general oxidative stress and a yet-unexploited therapeutic approach to degenerative diseases and aging. PMID:17360324

  2. Frequency Modulated Translocational Oscillations of Nrf2 Mediate the Antioxidant Response Element Cytoprotective Transcriptional Response

    PubMed Central

    Xue, Mingzhan; Momiji, Hiroshi; Rabbani, Naila; Barker, Guy; Bretschneider, Till; Shmygol, Anatoly; Rand, David A.

    2015-01-01

    Abstract Aims: Stress responsive signaling coordinated by nuclear factor erythroid 2-related factor 2 (Nrf2) provides an adaptive response for protection of cells against toxic insults, oxidative stress and metabolic dysfunction. Nrf2 regulates a battery of protective genes by binding to regulatory antioxidant response elements (AREs). The aim of this study was to examine how Nrf2 signals cell stress status and regulates transcription to maintain homeostasis. Results: In live cell microscopy we observed that Nrf2 undergoes autonomous translocational frequency-modulated oscillations between cytoplasm and nucleus. Oscillations occurred in quiescence and when cells were stimulated at physiological levels of activators, they decrease in period and amplitude and then evoke a cytoprotective transcriptional response. We propose a mechanism whereby oscillations are produced by negative feedback involving successive de-phosphorylation and phosphorylation steps. Nrf2 was inactivated in the nucleus and reactivated on return to the cytoplasm. Increased frequency of Nrf2 on return to the cytoplasm with increased reactivation or refresh-rate under stress conditions activated the transcriptional response mediating cytoprotective effects. The serine/threonine-protein phosphatase PGAM5, member of the Nrf2 interactome, was a key regulatory component. Innovation: We found that Nrf2 is activated in cells without change in total cellular Nrf2 protein concentration. Regulation of ARE-linked protective gene transcription occurs rather through translocational oscillations of Nrf2. We discovered cytoplasmic refresh rate of Nrf2 is important in maintaining and regulating the transcriptional response and links stress challenge to increased cytoplasmic surveillance. We found silencing and inhibition of PGAM5 provides potent activation of Nrf2. Conclusion: Frequency modulated translocational oscillations of Nrf2 mediate the ARE-linked cytoprotective transcriptional response. Antioxid. Redox

  3. Characterization of the antioxidant responsive element (ARE): A xenobiotic responsive element controlling expression of the rat glutathione S-transferase Ya subunit gene by phenolic antioxidants

    SciTech Connect

    Rushmore, T.H.; Pickett, C.B. )

    1991-03-11

    The antioxidant responsive element (ARE) is responsible for part of the basal level expression of the Ya subunit gene and for the induction by phenolic antioxidants and metabolites of planar aromatic hydrocarbons (PAH), such as {beta}-naphthoflavone ({beta}-NF). As an initial step in the characterization of the mechanism(s) by which phenolic antioxidants and metabolites of PAH activate transcription via the ARE, the authors prepared 5{prime} and 3{prime}-deletions and point mutants of the 41 bp ARE, transfected them into HepG2 cells and monitored the basal and {beta}-NF inducible activities. Deletion analysis permitted separation of the basal and {beta}-NF inducible components of the ARE. The minimum sequence required for {beta}-NF inducible expression was PuGTGACAAAGCAPu, nucleotides {minus}697 to {minus}687. Point mutations at nucleotides {minus}696, {minus}695, {minus}694, {minus}693, {minus}689 or {minus}688 abolished the {beta}-NF inducible expression. Mutations at the other positions had little or no effect on {beta}-NF inducible expression. Gel shift assays suggest that at least 2 proteins bind to regions within the ARE shown to be important for basal and {beta}-NF inducible expression.

  4. Cell-Based Assay for Identifying the Modulators of Antioxidant Response Element Signaling Pathway.

    PubMed

    Zhao, Jinghua; Shukla, Sunita J; Xia, Menghang

    2016-01-01

    The antioxidant response element (ARE) signaling pathway plays an important role in the amelioration of cellular oxidative stress. Thus, assays that detect this pathway can be useful for identifying chemicals that induce or inhibit oxidative stress signaling. The focus of this chapter is to describe a cell-based ARE assay in a quantitative high-throughput screening (qHTS) format to test a large collection of compounds that induce nuclear factor erythroid 2-related factor (Nrf2)/ARE signaling. The assay is described through cell handling, assay preparation, and instrument usage. PMID:27518623

  5. Isoniazid suppresses antioxidant response element activities and impairs adipogenesis in mouse and human preadipocytes

    SciTech Connect

    Chen, Yanyan; Xue, Peng; Hou, Yongyong; Zhang, Hao; Zheng, Hongzhi; Zhou, Tong; Qu, Weidong; Teng, Weiping; Zhang, Qiang; Andersen, Melvin E.; Pi, Jingbo

    2013-12-15

    Transcriptional signaling through the antioxidant response element (ARE), orchestrated by the Nuclear factor E2-related factor 2 (Nrf2), is a major cellular defense mechanism against oxidative or electrophilic stress. Here, we reported that isoniazid (INH), a widely used antitubercular drug, displays a substantial inhibitory property against ARE activities in diverse mouse and human cells. In 3T3-L1 preadipocytes, INH concentration-dependently suppressed the ARE-luciferase reporter activity and mRNA expression of various ARE-dependent antioxidant genes under basal and oxidative stressed conditions. In keeping with our previous findings that Nrf2-ARE plays a critical role in adipogenesis by regulating expression of CCAAT/enhancer-binding protein β (C/EBPβ) and peroxisome proliferator-activated receptor γ (PPARγ), suppression of ARE signaling by INH hampered adipogenic differentiation of 3T3-L1 cells and human adipose-derived stem cells (ADSCs). Following adipogenesis induced by hormonal cocktails, INH-treated 3T3-L1 cells and ADSCs displayed significantly reduced levels of lipid accumulation and attenuated expression of C/EBPα and PPARγ. Time-course studies in 3T3-L1 cells revealed that inhibition of adipogenesis by INH occurred in the early stage of terminal adipogenic differentiation, where reduced expression of C/EBPβ and C/EBPδ was observed. To our knowledge, the present study is the first to demonstrate that INH suppresses ARE signaling and interrupts with the transcriptional network of adipogenesis, leading to impaired adipogenic differentiation. The inhibition of ARE signaling may be a potential underlying mechanism by which INH attenuates cellular antioxidant response contributing to various complications. - Highlights: • Isoniazid suppresses ARE-mediated transcriptional activity. • Isoniazid inhibits adipogenesis in preadipocytes. • Isoniazid suppresses adipogenic gene expression during adipogenesis.

  6. Analysis of trace elements responsible for antioxidant protection by SRXFA method

    NASA Astrophysics Data System (ADS)

    Gonchar, A.; Kolmogorov, Yu; Dikalova, A.; Yelinova, V.; Kondratev, V.

    2001-09-01

    The possibilities of using the energy dispersion synchrotron radiation X-ray fluorescence analysis (SRXFA) for control of blood plasma and liver trace element (TE) content in rats with hyperproduction of oxygen radicals and hair TE content in women with mammary hyperplasia and cancer are demonstrated. Our data show that activity of antioxidant enzymes superoxide dismutase (SOD) and catalase in the blood and liver depends on the amount of TE incorporated into the structure of the active center of these enzymes, which are responsible for antioxidant protection. A decrease of activity of these enzymes is accompanied by an increase of production of free OH radicals in the tissues. Clinical data demonstrated that scalp hair of patients with oncological mammary pathology was characterized by a significant decrease of concentrations of selenium (Se) and zinc (Zn) and by an increase of chromium (Cr). The Se deficit was more pronounced in patients with cancer than in those with mammary hyperplasia ( p<0.05). The SRXFA method permits one to carry out a controllable correction of TE imbalance in many diseases whose development is caused by oxygen radical injury.

  7. Profiling Environmental Chemicals for Activity in the Antioxidant Response Element Signaling Pathway Using a High-Throughput Screening Approach

    EPA Science Inventory

    1 ABSTRACT 2 3 BACKGROUND: Oxidative stress has been implicated in the pathogenesis of a variety 4 of diseases ranging from cancer to neurodegeneration, highlighti.ng the need to identify 5 chemicals that can induce this effect. The antioxidant response element (ARE)...

  8. Profiling Environmental Chemicals in the Antioxidant Response Element Pathway using Quantitative High Throughput Screening (qHTS)

    EPA Science Inventory

    The antioxidant response element (ARE) signaling pathway plays an important role in the amelioration of oxidative stress, which can contribute to a number of diseases, including cancer. We screened 1408 NTP-provided substances in 1536-well qHTS format at concentrations ranging fr...

  9. Mechanism Profiling of Hepatotoxicity Caused by Oxidative Stress Using Antioxidant Response Element Reporter Gene Assay Models and Big Data

    PubMed Central

    Kim, Marlene Thai; Huang, Ruili; Sedykh, Alexander; Wang, Wenyi; Xia, Menghang; Zhu, Hao

    2015-01-01

    Background: Hepatotoxicity accounts for a substantial number of drugs being withdrawn from the market. Using traditional animal models to detect hepatotoxicity is expensive and time-consuming. Alternative in vitro methods, in particular cell-based high-throughput screening (HTS) studies, have provided the research community with a large amount of data from toxicity assays. Among the various assays used to screen potential toxicants is the antioxidant response element beta lactamase reporter gene assay (ARE-bla), which identifies chemicals that have the potential to induce oxidative stress and was used to test > 10,000 compounds from the Tox21 program. Objective: The ARE-bla computational model and HTS data from a big data source (PubChem) were used to profile environmental and pharmaceutical compounds with hepatotoxicity data. Methods: Quantitative structure–activity relationship (QSAR) models were developed based on ARE-bla data. The models predicted the potential oxidative stress response for known liver toxicants when no ARE-bla data were available. Liver toxicants were used as probe compounds to search PubChem Bioassay and generate a response profile, which contained thousands of bioassays (> 10 million data points). By ranking the in vitro–in vivo correlations (IVIVCs), the most relevant bioassay(s) related to hepatotoxicity were identified. Results: The liver toxicants profile contained the ARE-bla and relevant PubChem assays. Potential toxicophores for well-known toxicants were created by identifying chemical features that existed only in compounds with high IVIVCs. Conclusion: Profiling chemical IVIVCs created an opportunity to fully explore the source-to-outcome continuum of modern experimental toxicology using cheminformatics approaches and big data sources. Citation: Kim MT, Huang R, Sedykh A, Wang W, Xia M, Zhu H. 2016. Mechanism profiling of hepatotoxicity caused by oxidative stress using antioxidant response element reporter gene assay models and

  10. DNA and mRNA elements with complementary responses to hemin, antioxidant inducers, and iron control ferritin-L expression.

    PubMed

    Hintze, Korry J; Theil, Elizabeth C

    2005-10-18

    Ferritins, an ancient family of protein nanocages, concentrate iron in iron-oxy minerals for iron-protein biosynthesis and protection against oxy radical damage. Of the two genetic mechanisms that regulate rates of ferritin-L synthesis, DNA transcription and mRNA translation, more is known about mRNA regulation where iron targets complexes of an mRNA structure, the iron-responsive element (IRE) sequence, and ferritin IRE repressors (iron regulatory proteins 1 and 2). Neither the integration of mRNA and DNA regulation nor the ferritin-L DNA promoter are well studied. We now report the combined effects of DNA transcription and mRNA translation regulation of ferritin-L synthesis. First, the promoter of human ferritin-L, encoding the animal-specific subunit associated with human diseases, was identified, and contained an overlapping Maf recognition element (MARE) and antioxidant responsive element (ARE) that was positively regulated by tert-butylhydroquinone, sulforaphane, and hemin with responses comparable to thioredoxin reductase (ARE regulator) or quinone reductase (MARE/ARE regulator). Iron, a poor regulator of the ferritin-L promoter, was 800 times less effective than sulforaphane. Combining the ferritin-L MARE/ARE and IRE produced a response to hemin that was 3-fold greater than the sum of responses of the MARE/ARE or IRE alone. Regulation of ferritin-L by a MARE/ARE DNA sequence emphasizes the importance of ferritin-L in oxidative stress that complements the mRNA regulation in iron stress. Combining DNA and mRNA mechanisms of regulation, as for ferritin-L, illustrates the advantages of using two types of genetic targets to achieve sensitive responses to multiple signals.

  11. Activation of antioxidant response element in mouse primary cortical cultures with sesquiterpene lactones isolated from Tanacetum parthenium

    PubMed Central

    Fischedick, Justin T; Standiford, Miranda; Johnson, Delinda A.; De Vos, Ric C.H.; Todorović, Slađana; Banjanac, Tijana; Verpoorte, Rob; Johnson, Jeffrey A.

    2012-01-01

    Tanacetum parthenium (Asteraceae) produces biologically active sesquiterpene lactones (SL). Nuclear factor E2-related factor 2 (Nrf2) is a transcription factor known to activate a series of genes termed the antioxidant response element (ARE). Activation of the Nrf2/ARE may be useful for the treatment of neurodegenerative disease. In this study we isolated 11 sesquiterpene lactones from T. parthenium with centrifugal partition chromatography and semi-preparative HPLC. Compounds were screened in-vitro for their ability to activate the ARE on primary mouse cortical cultures as well as for their toxicity towards the cultures. All sesquiterpene lactones containing the α-methylene-γ-lactone moiety were able to activate the ARE although a number of compounds displayed significant cellular toxicity towards the cultures. The structure activity relationship of the sesquiterpene lactones indicate that the guaianolides isolated were more active and less toxic then the germacranolides. PMID:22923197

  12. Extract of Ziziphus jujuba Fruit (Jujube) Stimulates Expression of Enzymes Responsible for Heme Recycle via Anti-oxidant Response Element in Cultured Murine Macrophages.

    PubMed

    Chen, Jianping; Lam, Candy T W; Li, Zhonggui; Yao, Ping; Lin, Huangquan; Dong, Tina T X; Tsim, Karl W K

    2016-02-01

    Jujube, the fruit of Ziziphus jujuba Mill., is a functional food and commonly used as a health supplement worldwide. To study the beneficial role of jujube in heme iron recycling during erythrophagocytosis, the expression of heme oxygenase-1 (HO-1), biliverdin reductase A and B, and ferroportin were determined in jujube-treated cultured RAW 264.7 macrophages. Application of a chemically standardized jujube water extract in cultured RAW 264.7 cells for 24 h stimulated the expressions of HO-1, biliverdin reductase A, biliverdin reductase B, and ferroportin in a concentration-dependent manner, having the maximal responses from twofolds to threefolds. A plasmid containing anti-oxidant response element, a regulator for HO-1 transcription, was transfected into RAW 264.7 cells. Application of jujube water extract onto the transfected macrophages stimulated the anti-oxidant response element-mediated transcriptional activity by twofolds. These results supported the potential capacity of jujube by regulating expressions of heme iron recycling genes in cultured macrophages.

  13. Effect of iron stress on Withania somnifera L.: antioxidant enzyme response and nutrient elemental uptake of in vitro grown plants.

    PubMed

    Rout, Jyoti Ranjan; Behera, Sadhana; Keshari, Nitin; Ram, Shidharth Sankar; Bhar, Subhajit; Chakraborty, Anindita; Sudarshan, Mathummal; Sahoo, Santi Lata

    2015-03-01

    In the present study the response of antioxidant enzyme activities and the level of expression of their corresponding genes on bioaccumulation of iron (Fe) were investigated. In vitro germinated Withania somnifera L. were grown in Murashige and Skoog's liquid medium with increasing concentrations (0, 25, 50, 100 and 200 µM) of FeSO4 for 7 and 14 days. Root and leaf tissues analyzed for catalase (CAT, EC 1.11.1.6), superoxide dismutase (SOD, EC 1.15.1.1) and guaiacol peroxidase (GPX, EC 1.11.1.7), have shown an increase in content with respect to exposure time. Isoforms of CAT, SOD and GPX were separated using non-denaturing polyacrylamide gel electrophoresis and observed that the isoenzymes were greatly affected by higher concentrations of Fe. Reverse transcriptase polymerase chain reaction analysis performed by taking three pairs of genes of CAT (RsCat, Catalase1, Cat1) and SOD (SodCp, TaSOD1.2, MnSOD) to find out the differential expression of antioxidant genes under Fe excess. RsCat from CAT and MnSOD from SOD have exhibited high levels of gene expression under Fe stress, which was consistent with the changes of the activity assayed in solution after 7 days of treatment. Analysis by proton induced X-ray emission exhibited an increasing uptake of Fe in plants by suppressing and expressing of other nutrient elements. The results of the present study suggest that higher concentration of Fe causes disturbance in nutrient balance and induces oxidative stress in plant.

  14. Immunohistochemical Study of Nrf2-Antioxidant Response Element as Indicator of Oxidative Stress Induced by Cadmium in Developing Rats

    PubMed Central

    Montes, Sergio; Juárez-Rebollar, Daniel; Nava-Ruíz, Concepción; Sánchez-García, Aurora; Heras-Romero, Yesica; Rios, Camilo; Méndez-Armenta, Marisela

    2015-01-01

    In developing animals, Cadmium (Cd) induces toxicity to many organs including brain. Reactive oxygen species (ROS) are often implicated in Cd-inducedtoxicity and it has been clearly demonstrated that oxidative stress interferes with the expression of genes as well as transcriptional factors such as Nrf2-dependent Antioxidant Response Element (Nrf2-ARE). Cd-generated oxidative stress and elevated Nrf2 activity have been reported in vitro and in situ cells. In this study we evaluated the morphological changes and the expression pattern of Nrf2 and correlated them with the Cd concentrations in different ages of developing rats in heart, lung, kidney, liver, and brain. The Cd content in different organs of rats treated with the metal was increased in all ages assayed. Comparatively, lower Cd brain levels were found in rats intoxicated at the age of 12 days, then pups treated at 5, 10, or 15 days old, at the same metal dose. No evident changes, as a consequence of cadmium exposure, were evident in the morphological analysis in any of the ages assayed. However, Nrf2-ARE immunoreactivity was observed in 15-day-old rats exposed to Cd. Our results support that fully developed blood-brain barrier is an important protector against Cd entrance to brain and that Nrf2 increased expression is a part of protective mechanism against cadmium-induced toxicity. PMID:26101558

  15. Plant Extracts of the Family Lauraceae: A Potential Resource for Chemopreventive Agents that Activate the Nuclear Factor-Erythroid 2-Related Factor 2/Antioxidant Response Element Pathway

    PubMed Central

    Shen, Tao; Chen, Xue-Mei; Harder, Bryan; Long, Min; Wang, Xiao-Ning; Lou, Hong-Xiang; Wondrak, Georg T.; Ren, Dong-Mei; Zhang, Donna D.

    2015-01-01

    Cells and tissues counteract insults from exogenous or endogenous carcinogens through the expression of genes encoding antioxidants and phase II detoxifying enzymes regulated by antioxidant response element promoter regions. Nuclear factor-erythroid 2-related factor 2 plays a key role in regulating the antioxidant response elements-target gene expression. Hence, the Nrf2/ARE pathway represents a vital cellular defense mechanism against damage caused by oxidative stress and xenobiotics, and is recognized as a potential molecular target for discovering chemo-preventive agents. Using a stable antioxidant response element luciferase reporter cell line derived from human breast cancer MDA-MB-231 cells combined with a 96-well high-throughput screening system, we have identified a series of plant extracts from the family Lauraceae that harbor Nrf2-inducing effects. These extracts, including Litsea garrettii (ZK-08), Cinnamomum chartophyllum (ZK-02), C. mollifolium (ZK-04), C. camphora var. linaloolifera (ZK-05), and C. burmannii (ZK-10), promoted nuclear translocation of Nrf2, enhanced protein expression of Nrf2 and its target genes, and augmented intracellular glutathione levels. Cytoprotective activity of these extracts against two electrophilic toxicants, sodium arsenite and H2O2, was investigated. Treatment of human bronchial epithelial cells with extracts of ZK-02, ZK-05, and ZK-10 significantly improved cell survival in response to sodium arsenite and H2O2, while ZK-08 showed a protective effect against only H2O2. Importantly, their protective effects against insults from both sodium arsenite and H2O2 were Nrf2-dependent. Therefore, our data provide evidence that the selected plants from the family Lauraceae are potential sources for chemopreventive agents targeting the Nrf2/ARE pathway. PMID:24585092

  16. Hepatic expression of heme oxygenase-1 and antioxidant response element-mediated genes following administration of ethinyl estradiol to rats

    SciTech Connect

    Morio, Lisa A.; Leone, Angelique; Sawant, Sharmilee P.; Nie, Alex Y.; Brandon Parker, J.; Taggart, Peter; Barron, Alfred M.; McMillian, Michael K. . E-mail: mmcmilli@prdus.jnj.com; Lord, Peter

    2006-11-01

    Heme oxygenase-1 (HO-1) is one of several enzymes induced by hepatotoxicants, and is thought to have an important protective role against cellular stress during liver inflammation and injury. The objective of the present study was to evaluate the role of HO-1 in estradiol-induced liver injury. A single dose of ethinyl estradiol (500 mg/kg, po) resulted in mild liver injury. Repeated administration of ethinyl estradiol (500 mg/kg/day for 4 days, po) resulted in no detectable liver injury or dysfunction. Using RT-PCR analysis, we demonstrate that HO-1 gene expression in whole liver tissue is elevated (> 20-fold) after the single dose of ethinyl estradiol. The number and intensity of HO-1 immunoreactive macrophages were increased after the single dose of ethinyl estradiol. HO-1 expression was undetectable in hepatic parenchymal cells from rats receiving Methocel control or a single dose of ethinyl estradiol, however cytosolic HO-1 immunoreactivity in these cells after repeated dosing of ethinyl estradiol was pronounced. The increases in HO-1 mRNA and HO-1 immunoreactivity following administration of a single dose of ethinyl estradiol suggested that this enzyme might be responsible for the observed protection of the liver during repeated dosing. To investigate the effect of HO-1 expression on ethinyl estradiol-induced hepatotoxicity, rats were pretreated with hemin (50 {mu}mol/kg, ip, a substrate and inducer of HO-1), with tin protoporphyrin IX (60 {mu}mol/kg, ip, an HO-1 inhibitor), or with gadolinium chloride (10 mg/kg, iv, an inhibitor/toxin of Kupffer cells) 24 h before ethinyl estradiol treatment. Pretreatment with modulators of HO-1 expression and activity had generally minimal effects on ethinyl estradiol-induced liver injury. These data suggest that HO-1 plays a limited role in antioxidant defense against ethinyl estradiol-induced oxidative stress and hepatotoxicity, and suggests that other coordinately induced enzymes are responsible for protection observed

  17. Licochalcone E activates Nrf2/antioxidant response element signaling pathway in both neuronal and microglial cells: therapeutic relevance to neurodegenerative disease.

    PubMed

    Kim, Sa Suk; Lim, Juhee; Bang, Yeojin; Gal, Jiyeong; Lee, Sang-Uk; Cho, Young-Chang; Yoon, Goo; Kang, Bok Yun; Cheon, Seung Hoon; Choi, Hyun Jin

    2012-10-01

    Oxidative stress and neuroinflammation are hallmarks of neurodegenerative diseases, which do not play independently but work synergistically through complex interactions exacerbating neurodegeneration. Therefore, the mechanism that is directly implicated in controlling oxidative stress and inflammatory response could be an attractive strategy to prevent the onset and/or delay the progression of neurodegenerative diseases. The transcription factor nuclear factor-E2-related factor-2 (Nrf2) is the guardian of redox homeostasis by regulating a battery of antioxidant and phase II detoxification genes, which are relevant to defense mechanism against oxidative stress and inflammatory responses. In this study, we show that a recently identified Glycyrrhiza-inflata-derived chalcone, licochalcone E (Lico-E), attenuates lipopolysaccharide-induced inflammatory responses in microglial BV2 cells and protects dopaminergic SH-SY5Y cells from 6-hydroxydopamine cytotoxicity. Lico-E activates Nrf2-antioxidant response element (ARE) system and up-regulates downstream NAD(P)H:quinone oxidoreductase 1 (NQO1) and heme oxygenase-1 (HO-1). Anti-inflammatory and cytoprotective effects of Lico-E are attenuated in siRNA-mediated Nrf2-silencing cells as well as in the presence with specific inhibitor of HO-1 or NQO1, respectively. Lico-E also has neuroprotective effect against 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine-induced nigrostriatal dopaminergic neurodegeneration in mice, with up-regulation of HO-1 and NQO1 in the substantia nigra of the brain. This study demonstrates that Lico-E is a potential activator of the Nrf2/ARE-dependent pathway and is therapeutically relevant not only to oxidative-stress-related neurodegeneration but also inflammatory responses of microglial cells both in vitro and in vivo.

  18. Caffeic acid phenethyl ester stimulates human antioxidant response element-mediated expression of the NAD(P)H:quinone oxidoreductase (NQO1) gene.

    PubMed

    Jaiswal, A K; Venugopal, R; Mucha, J; Carothers, A M; Grunberger, D

    1997-02-01

    Caffeic acid phenethyl ester (CAPE) is a phenolic antioxidant derived from the propolis of honeybee hives. CAPE was shown to inhibit the formation of intracellular hydrogen peroxide and oxidized bases in DNA of 12-O-tetradecanoylphorbol-13-acetate (TPA)-treated HeLa cells and was also found to induce a redox change that correlated with differential growth effects in transformed cells but not the nontumorigenic parental ones. Mediated via the electrophile or human antioxidant response element (hARE), induction of the expression of NAD(P)H quinone oxidoreductase (NQO1) and glutathione S-transferase Ya subunit genes by certain phenolic antioxidants has been correlated with the chemopreventive properties of these agents. Here, we determined by Northern analysis that CAPE treatment of hepatoma cells stimulates NQO1 gene expression in cultured human hepatoma cells (HepG2), and we characterized the effects of CAPE treatment on the expression of a reporter gene either containing or lacking the hARE or carrying a mutant version of this element in rodent hepatoma (Hepa-1) transfectants. A dose-dependent transactivation of human hARE-mediated chloramphenicol acetyltransferase (cat) gene expression was observed upon treatments of the Hepa-1 transfectants with TPA, a known inducer, as well as with CAPE. The combined treatments resulted in an apparent additive stimulation of the reporter expression. To learn whether this activation of cat gene expression was effected by protein kinase C in CAPE-treated cells, a comparison was made of cat gene activity after addition of calphostin, a protein kinase C inhibitor. Calphostin reduced the cat gene induction by TPA but not by CAPE, suggesting that stimulation of gene expression in this system by these agents proceeds via distinct mechanisms. Band-shift experiments to examine binding of transactivator proteins from nuclear extracts of treated and untreated cells to a hARE DNA probe showed that TPA exposure increased the binding level

  19. Human antioxidant-response-element-mediated regulation of type 1 NAD(P)H:quinone oxidoreductase gene expression. Effect of sulfhydryl modifying agents.

    PubMed

    Li, Y; Jaiswal, A K

    1994-11-15

    Human antioxidant-response element (hARE) containing two copies of the AP1/AP1-like elements arranged as inverse repeat is known to mediate basal and beta-naphthoflavone-induced transcription of the type 1 NAD(P)H:quinone oxidoreductase (NQO1) gene. Band-shift assays revealed that beta-naphthoflavone increased binding of nuclear proteins at the hARE. Super shift assays identified Jun-D and c-Fos proteins in the band-shift complexes observed with control and beta-naphthoflavone-treated Hepa-1 nuclear extracts. Hepa-1 cells stably transformed with hARE-tk-chloramphenicol acetyl transferase (CAT) recombinant plasmid were used to demonstrate that, in addition to beta-naphthoflavone, a variety of antioxidants, tumor promoters and hydrogen peroxide (H2O2) also increased expression of hARE-mediated CAT gene. beta-naphthoflavone induction of the CAT gene expression in Hepa-1 cells was found insensitive to inhibitors of protein kinase C and tyrosine kinases. However, binding of regulatory proteins at the hARE and the CAT gene expression in Hepa-1 cells were increased by dithiothreitol, 2-mercaptoethanol and diamide. Treatment of the Hepa-1 cells with N-ethylmaleimide reduced binding of proteins at the hARE and interfered with expression and beta-naphthoflavone induction of the CAT gene. These results suggested a role of sulfhydryl modification of hARE binding (Jun and Fos) proteins which mediate basal and induced expression of the NQO1 gene. We also report that in-vitro-translated products of the proto-oncogenes, Jun and Fos, bind to the hARE in band-shift assays. The incubation of Jun and Fos proteins with small amounts of nuclear extract from dimethylsulfoxide-treated (control) or beta-naphthoflavone treated Hepa-1 cells prior to band-shift assays increased the binding of Jun and Fos proteins to the hARE. Interestingly, the increase in binding of Jun and Fos proteins to the hARE was more prominent with beta-naphthoflavone-treated nuclear extract as compared to the control

  20. NRF2 Regulates Hyperoxia-induced NOX4 expression in Human Lung Endothelium: Identification of functional antioxidant response elements on NOX4 promoter

    PubMed Central

    Pendyala, Srikanth; Moitra, Jaideep; Kalari, Satish; Kleeberger, Steven R.; Zhao, Yutong; Reddy, Sekhar P.; Garcia, Joe G.N.; Natarajan, Viswanathan

    2011-01-01

    Reactive oxygen species (ROS) generated by vascular endothelial and smooth muscle cells contribute to the development and progression of vascular diseases. We have recently shown that hyperoxia enhances NADPH Oxidase 4 (NOX4) expression, which regulates lung endothelial cell migration and angiogenesis. Regulation of NOX4 is poorly understood in the vasculature. The objective of this study is to identify transcriptional factor(s) involved in regulation of endothelial NOX4. We found that hyperoxia induced NOX4 expression was markedly reduced in Nrf2-/- mice, compared to Nrf2+/+ mice. Exposure of human lung microvascular endothelial cells (HLMVECs) to hyperoxia stimulated NRF2 translocation from the cytoplasm to the nucleus and increased NOX4 expression. Knock down of NRF2 expression using a siRNA approach attenuated basal NOX4 expression; however, it enhanced superoxide/ROS generation under both normoxia and hyperoxia. In silico analysis revealed presence of at least three consensus sequences for the antioxidant response element (ARE) in the promoter region of NOX4. In transient transfections, hyperoxia stimulated NOX4promoter activity in HLMVECs, and deletion of -438 to -458 and -619 to -636 sequences markedly reduced hyperoxia-stimulated NOX4 promoter activation. ChIP analysis revealed an enhanced recruitment of NRF2 to endogenous NOX4 promoter spanning these two AREs following hyperoxic insult. Collectively, these results demonstrate, for the first time, a novel role of NRF2 in regulating hyperoxia-induced NOX4 transcription via AREs in lung endothelium. PMID:21443946

  1. Aged garlic extract enhances heme oxygenase-1 and glutamate-cysteine ligase modifier subunit expression via the nuclear factor erythroid 2-related factor 2-antioxidant response element signaling pathway in human endothelial cells.

    PubMed

    Hiramatsu, Kei; Tsuneyoshi, Tadamitsu; Ogawa, Takahiro; Morihara, Naoaki

    2016-02-01

    The nuclear factor erythroid 2-related factor 2 (Nrf2)-antioxidant response element (ARE) pathway defends cells against oxidative stress and regulates the cellular redox balance. Activation of this pathway induces a variety of antioxidant enzymes, resulting in the protection of our bodies against oxidative damage. It has been reported that aged garlic extract (AGE), a garlic preparation that is rich in water-soluble cysteinyl moieties, reduces oxidative stress and helps to ameliorate of cardiovascular, renal and hepatic diseases. We hypothesized that AGE enhances the expression of antioxidant enzymes via the Nrf2-ARE pathway in human umbilical vein endothelial cells in culture. Gene expression of antioxidant enzymes was measured using real-time polymerase chain reaction. Nuclear accumulation of Nrf2 and antioxidant enzymes expression were evaluated using western blotting analyses. We found that AGE promoted the accumulation of Nrf2 into the nucleus in a time- and dose-dependent manner and increased the gene expression and polypeptide level of heme oxygenase-1 (HO-1) and glutamate-cysteine ligase modifier subunit (GCLM). Moreover, the effect of AGE in elevating the gene expression of HO-1 and GCLM was found to be mediated via Nrf2 activation in human umbilical vein endothelial cells. Taken together, these observations suggest that AGE induces the expression of HO-1 and GCLM, which are antioxidant enzymes, via activation of the Nrf2-ARE signaling pathway. PMID:26507778

  2. Mangiferin activates Nrf2-antioxidant response element signaling without reducing the sensitivity to etoposide of human myeloid leukemia cells in vitro

    PubMed Central

    Zhang, Ben-ping; Zhao, Jie; Li, Shan-shan; Yang, Li-jing; Zeng, Ling-lan; Chen, Yan; Fang, Jun

    2014-01-01

    Aim: Mangiferin is glucosylxanthone extracted from plants of the Anacardiaceae and Gentianaceae families. The aim of this study was to investigate the effects of mangiferin on Nrf2-antioxidant response element (ARE) signaling and the sensitivity to etoposide of human myeloid leukemia cells in vitro. Methods: Human HL-60 myeloid leukemia cells and mononuclear human umbilical cord blood cells (MNCs) were examined. Nrf2 protein was detected using immunofluorescence staining and Western blotting. Binding of Nrf2 to ARE was examined with electrophoretic mobility shift assay. The level of NQO1 was assessed with real-time RT-PCR and Western blotting. DCFH-DA was used to evaluate intracellular ROS level. Cell proliferation and apoptosis were analyzed using MTT and flow cytometry, respectively. Results: Mangiferin (50 μmol/L) significantly increased Nrf2 protein accumulation in HL-60 cells, particularly in the nucleus. Mangiferin also enhanced the binding of Nrf2 to an ARE, significantly up-regulated NQO1 expression and reduced intracellular ROS in HL60 cells. Mangiferin alone dose-dependently inhibited the proliferation of HL-60 cells. Mangiferin (50 mol/L) did not attenuate etoposide-induced cytotoxicity in HL-60 cells, and combined treatment of mangiferin with low concentration of etoposide (0.8 μg/mL) even increased the cell inhibition rate. Nor did mangiferin change the rate of etoposide-induced apoptosis in HL-60 cells. In MNCs, mangiferin significantly relieved oxidative stress, but attenuated etoposide-induced cytotoxicity. Conclusion: Mangiferin is a novel Nrf2 activator that reduces oxidative stress and protects normal cells without reducing the sensitivity to etoposide of HL-60 leukemia cells in vitro. Mangiferin may be a potential chemotherapy adjuvant. PMID:24374812

  3. Activation of nuclear protein binding to the antioxidant/electrophile response element in vascular smooth muscle cells by benzo(a)pyrene.

    PubMed

    Holderman, M T; Miller, K P; Ramos, K S

    2000-01-01

    This laboratory has previously shown that binding of nuclear proteins to the antioxidant/electrophile response element (ARE/EpRE) participates in deregulation of vascular gene expression by benzo(a)pyrene (BaP), a suspected atherogen. In the present study, oligonucleotides representing ARE/EpREs within the c-Ha-ras and glutathione-S-transferase (GST-Ya) promoters were employed to evaluate the role of flanking sequences in stabilizing protein:DNA interactions in BaP-treated vascular smooth muscle cells (vSMCs). We also wanted to define promoter-specific patterns of protein recognition to ARE/EpREs in this cell system. In electrophoretic mobility shift assays (EMSA), optimal protein binding to a human Ha-ras ARE/EpRE variant sequence fitted to match the extended mouse(m) GST-Ya ARE/EpRE core (5'-TMAnnRTGAYnnnGCR-3') was dependent on 5' nucleic acid sequence. Using immobilized DNA affinity chromatography (IDAC), we identified four nuclear proteins of M(r) 62, 60, 50, and 30 kDa that associated specifically with the mGSTYa ARE/EpRE. Photo crosslinking to a BrdU-substituted hHa-ras or mGST ARE/EpRE probe identified specific proteins of M(r) 80, 60, 55, 25, 23 kDa or 80, 60, 55, 27, 25, 23 kDa, respectively. Protein:DNA complexes detected using IDAC eluate overlapped with those observed in crude nuclear extracts. Chemical treatments known to modulate ARE/EpRE protein binding in vSMCs did not alter overall protein:DNA affinity and/or sequence recognition to either hHa-ras or mGST-Ya elements. We conclude that nucleotide sequences 5' to the core ARE/EpRE influence specific binding of nuclear proteins and that multiple proteins bind to ARE/EpREs in a promoter-specific manner in vSMCs.

  4. Antioxidant Vitamins and Trace Elements in Critical Illness.

    PubMed

    Koekkoek, W A C Kristine; van Zanten, Arthur R H

    2016-08-01

    This comprehensive narrative review summarizes relevant antioxidant mechanisms, the antioxidant status, and effects of supplementation in critically ill patients for the most studied antioxidant vitamins A, C, and E and the enzyme cofactor trace elements selenium and zinc. Over the past 15 years, oxidative stress-mediated cell damage has been recognized to be fundamental to the pathophysiology of various critical illnesses such as acute respiratory distress syndrome, ischemia-reperfusion injury, and multiorgan dysfunction in sepsis. Related to these conditions, low plasma levels of antioxidant enzymes, vitamins, and trace elements have been frequently reported, and thus supplementation seems logical. However, low antioxidant plasma levels per se may not indicate low total body stores as critical illness may induce redistribution of antioxidants. Furthermore, low antioxidant levels may even be beneficial as pro-oxidants are essential in bacterial killing. The reviewed studies in critically ill patients show conflicting results. This may be due to different patient populations, study designs, timing, dosing regimens, and duration of the intervention and outcome measures evaluated. Therefore, at present, it remains unclear whether supplementation of antioxidant micronutrients has any clinical benefit in critically ill patients as some studies show clear benefits, whereas others demonstrate neutral outcomes and even harm. Combination therapy of antioxidants seems logical as they work in synergy and function as elements of the human antioxidant network. Further research should focus on defining the normal antioxidant status for critically ill patients and to study optimal supplement combinations either by nutrition enrichment or by enteral or parenteral pharmacological interventions.

  5. Senescence responsive transcriptional element

    DOEpatents

    Campisi, Judith; Testori, Alessandro

    1999-01-01

    Recombinant polynucleotides have expression control sequences that have a senescence responsive element and a minimal promoter, and which are operatively linked to a heterologous nucleotide sequence. The molecules are useful for achieving high levels of expression of genes in senescent cells. Methods of inhibiting expression of genes in senescent cells also are provided.

  6. Senescence responsive transcriptional element

    SciTech Connect

    Campisi, J.; Testori, A.

    1999-10-12

    Recombinant polynucleotides have expression control sequences that have a senescence responsive element and a minimal promoter, and which are operatively linked to a heterologous nucleotide sequence. The molecules are useful for achieving high levels of expression of genes in senescent cells. Methods of inhibiting expression of genes in senescent cells also are provided.

  7. Antioxidant Vitamins and Trace Elements in Critical Illness.

    PubMed

    Koekkoek, W A C Kristine; van Zanten, Arthur R H

    2016-08-01

    This comprehensive narrative review summarizes relevant antioxidant mechanisms, the antioxidant status, and effects of supplementation in critically ill patients for the most studied antioxidant vitamins A, C, and E and the enzyme cofactor trace elements selenium and zinc. Over the past 15 years, oxidative stress-mediated cell damage has been recognized to be fundamental to the pathophysiology of various critical illnesses such as acute respiratory distress syndrome, ischemia-reperfusion injury, and multiorgan dysfunction in sepsis. Related to these conditions, low plasma levels of antioxidant enzymes, vitamins, and trace elements have been frequently reported, and thus supplementation seems logical. However, low antioxidant plasma levels per se may not indicate low total body stores as critical illness may induce redistribution of antioxidants. Furthermore, low antioxidant levels may even be beneficial as pro-oxidants are essential in bacterial killing. The reviewed studies in critically ill patients show conflicting results. This may be due to different patient populations, study designs, timing, dosing regimens, and duration of the intervention and outcome measures evaluated. Therefore, at present, it remains unclear whether supplementation of antioxidant micronutrients has any clinical benefit in critically ill patients as some studies show clear benefits, whereas others demonstrate neutral outcomes and even harm. Combination therapy of antioxidants seems logical as they work in synergy and function as elements of the human antioxidant network. Further research should focus on defining the normal antioxidant status for critically ill patients and to study optimal supplement combinations either by nutrition enrichment or by enteral or parenteral pharmacological interventions. PMID:27312081

  8. Nrf1 and Nrf2 positively and c-Fos and Fra1 negatively regulate the human antioxidant response element-mediated expression of NAD(P)H:quinone oxidoreductase1 gene.

    PubMed

    Venugopal, R; Jaiswal, A K

    1996-12-10

    Twenty-four base pairs of the human antioxidant response element (hARE) are required for high basal transcription of the NAD(P)H:quinone oxidoreductase1 (NQO1) gene and its induction in response to xenobiotics and antioxidants. hARE is a unique cis-element that contains one perfect and one imperfect AP1 element arranged as inverse repeats separated by 3 bp, followed by a "GC" box. We report here that Jun, Fos, Fra, and Nrf nuclear transcription factors bind to the hARE. Overexpression of cDNA derived combinations of the nuclear proteins Jun and Fos or Jun and Fra1 repressed hARE-mediated chloramphenicol acetyltransferase (CAT) gene expression in transfected human hepatoblastoma (Hep-G2) cells. Further experiments suggested that this repression was due to overexpression of c-Fos and Fra1, but not due to Jun proteins. The Jun (c-Jun, Jun-B, and Jun-D) proteins in all the possible combinations were more or less ineffective in repression or upregulation of hARE-mediated gene expression. Interestingly, overexpression of Nrf1 and Nrf2 individually in Hep-G2 and monkey kidney (COS1) cells significantly increased CAT gene expression from reporter plasmid hARE-thymidine kinase-CAT in transfected cells that were inducible by beta-naphthoflavone and teri-butyl hydroquinone. These results indicated that hARE-mediated expression of the NQO1 gene and its induction by xenobiotics and antioxidants are mediated by Nrf1 and Nrf2. The hARE-mediated basal expression, however, is repressed by overexpression of c-Fos and Fra1. PMID:8962164

  9. Induction of activation of the antioxidant response element and stabilization of Nrf2 by 3-(3-pyridylmethylidene)-2-indolinone (PMID) confers protection against oxidative stress-induced cell death

    SciTech Connect

    Yao, Jia-Wei; Liu, Jing; Kong, Xiang-Zhen; Zhang, Shou-Guo; Wang, Xiao-Hui; Yu, Miao; Zhan, Yi-Qun; Li, Wei; Xu, Wang-Xiang; Tang, Liu-Jun; Ge, Chang-Hui; Wang, Lin; Li, Chang-Yan; Yang, Xiao-Ming

    2012-03-01

    The antioxidant response elements (ARE) are a cis-acting enhancer sequence located in regulatory regions of antioxidant and detoxifying genes. Nuclear factor (erythroid-derived 2)-like 2 (Nrf2) is a member of the Cap ‘n’ Collar family of transcription factors that binds to the ARE and regulates the transcription of specific ARE-containing genes. Under oxidative stress, Nrf2/ARE induction is fundamental to defense against reactive oxygen species (ROS) and serves as a key factor in the protection against toxic xenobiotics. 3-(3-Pyridylmethylidene)-2-Indolinone (PMID) is a derivative of 2-indolinone compounds which act as protein kinase inhibitors and show anti-tumor activity. However, the role of PMID in the oxidative stress remains unknown. In the present study, we showed that PMID induced the activation of ARE-mediated transcription, increased the DNA-binding activity of Nrf2 and then up-regulated the expression of antioxidant genes such as HO-1, SOD, and NQO1. The level of Nrf2 protein was increased in cells treated with PMID by a post-transcriptional mechanism. Under CHX treatment, the stability of Nrf2 protein was enhanced by PMID with decreased turnover rate. We showed that PMID reduced the ubiquitination of Nrf2 and disrupted the Cullin3 (Cul3)-Keap1 interaction. Furthermore, cells treated with PMID showed resistance to cytotoxicity by H{sub 2}O{sub 2} and pro-oxidant 6-OHDA. PMID also up-regulated the antioxidant level in BALB/c mice. Taken together, the compound PMID induces the ARE-mediated gene expression through stabilization of Nrf2 protein and activation of Nrf2/ARE pathway and protects against oxidative stress-mediated cell death. -- Highlights: ► PMID up-regulates ARE-mediated antioxidant gene expression in vitro and in vivo. ► PMID enhances the stabilization of Nrf2 protein, decreasing Nrf2 turnover rate. ► PMID disrupted the Cullin3 (Cul3)-Keap1 interaction. ► PMID protects against cell death induced by H{sub 2}O{sub 2} and pro-oxidant 6

  10. In Vivo Effect of Arsenic Trioxide on Keap1-p62-Nrf2 Signaling Pathway in Mouse Liver: Expression of Antioxidant Responsive Element-Driven Genes Related to Glutathione Metabolism

    PubMed Central

    Srivastava, Ritu; Sengupta, Archya; Mukherjee, Sandip; Chatterjee, Sarmishtha; Sudarshan, Muthammal; Chakraborty, Anindita; Bhattacharya, Shelley; Chattopadhyay, Ansuman

    2013-01-01

    Arsenic is a Group I human carcinogen, and chronic arsenic exposure through drinking water is a major threat to human population. Liver is one of the major organs for the detoxification of arsenic. The present study was carried out in mice in vivo after arsenic treatment through drinking water at different doses and time of exposure. Arsenic toxicity is found to be mediated by reactive oxygen species. Nuclear factor (erythroid-2 related) factor 2 (Nrf2)/Keap1 (Kelch-like ECH-associated protein 1)/ARE (antioxidant response element)—driven target gene system protects cells against oxidative stress and maintains cellular oxidative homeostasis. Our result showed 0.4 ppm, 2 ppm, and 4 ppm arsenic trioxide treatment through drinking water for 30 days and 90 days induced damages in the liver of Swiss albino mice as evidenced by histopathology, disturbances in liver function, induction of heat shock protein 70, modulation of trace elements, alteration in reduced glutathione level, glutathione-s-transferase and catalase activity, malondialdehyde production, and induction of apoptosis. Cellular Nrf2 protein level and mRNA level increased in all treatment groups. Keap1 protein as well as mRNA level decreased concomitantly in arsenic treated mice. Our study clearly indicates the important role of Nrf2 in activating ARE driven genes related to GSH metabolic pathway and also the adaptive response mechanisms in arsenic induced hepatotoxicity. PMID:27335833

  11. Characterization of the rat glutathione S-transferase Yc2 subunit gene, GSTA5: identification of a putative antioxidant-responsive element in the 5'-flanking region of rat GSTA5 that may mediate chemoprotection against aflatoxin B1.

    PubMed

    Pulford, D J; Hayes, J D

    1996-08-15

    We have isolated and characterized genomic DNA encoding the rat glutathione S-transferase Yc2 subunit. This protein is now referred to as rGSTA5 and is noteworthy because of its high activity towards aflatoxin B1-8,9-epoxide, its marked inducibility by chemoprotectors, its sex-specific regulation, and its over-expression in hepatoma and preneoplastic nodules. The rGSTA5 gene, which was isolated on two overlapping bacteriophage lambda clones, is approx. 12 kb in length and, unlike other class Alpha genes described to date, it comprises six exons. The transcription start site has been identified 228 bp upstream from the ATG translational initiation codon, and is situated 51 bp downstream from a consensus TATA-box. Deletion analysis, using luciferase reporter constructs, has shown that the region between -177 bp and +65 bp from the transcriptional start site contains a functional promoter. Computer-assisted analysis of the upstream sequence has indicated the presence of an antioxidant-responsive element (ARE), and several elements thought to be required for tissue-specific expression of the enzyme. In addition, several putative oestrogen-responsive half sites were observed in both upstream and intronic sequences. PMID:8761455

  12. Ethanol Extract of Cirsium japonicum var. ussuriense Kitamura Exhibits the Activation of Nuclear Factor Erythroid 2-Related Factor 2-dependent Antioxidant Response Element and Protects Human Keratinocyte HaCaT Cells Against Oxidative DNA Damage

    PubMed Central

    Yoo, Ok-Kyung; Choi, Bu Young; Park, Jin-Oh; Lee, Ji-Won; Park, Byoung-Kwon; Joo, Chul Gue; Heo, Hyo-Jung; Keum, Young-Sam

    2016-01-01

    Keratinocytes are constantly exposed to extracellular insults, such as ultraviolet B, toxic chemicals and mechanical stress, all of which can facilitate the aging of keratinocytes via the generation of intracellular reactive oxygen species (ROS). Nuclear factor erythroid 2-related factor 2 (Nrf2) is a transcription factor that plays a critical role in protecting keratinocytes against oxidants and xenobiotics by binding to the antioxidant response element (ARE), a cis-acting element existing in the promoter of most phase II cytoprotective genes. In the present study, we have attempted to find novel ethanol extract(s) of indigenous plants of Jeju island, Korea that can activate the Nrf2/ARE-dependent gene expression in human keratinocyte HaCaT cells. As a result, we identified that ethanol extract of Cirsium japonicum var. ussuriense Kitamura (ECJUK) elicited strong stimulatory effect on the ARE-dependent gene expression. Supporting this observation, we found that ECJUK induced the expression of Nrf2, hemoxygenase-1, and NAD(P)H:quinone oxidoreductase-1 and this event was correlated with Akt1 phosphorylation. We also found that ECJUK increased the intracellular reduced glutathione level and suppressed 12-O-tetradecanoylphorbol acetate-induced 8-hydroxyguanosine formation without affecting the overall viability. Collectively, our results provide evidence that ECJUK can protect against oxidative stress-mediated damages through the activation of Nrf2/ARE-dependent phase II cytoprotective gene expression. PMID:27051652

  13. Antioxidant responses of rice seedling to Ce⁴+ under hydroponic cultures.

    PubMed

    Xu, Qiu-Man; Chen, Hong

    2011-09-01

    Since the 1980s, rare earth elements have been commonly used in China because of their enriched fertilizers. To understand the potential benefits or damages of Ce(4+) on rice, the antioxidant responses (superoxide dismutase, ascorbate peroxidase, catalase activities, and ascorbate and glutathione contents) of rice seedling to Ce(4+) under hydroponic cultures were investigated. The results showed that Ce(4+) induced H(2)O(2) and O(2)(-) production of rice seedling. The inhibition studies with diphenylene iodonium suggested that the key enzyme responsible for oxidative bursts was primarily NADPH oxidase. Ce(4+) (0.02 mM) increased the antioxidant capacity of reduced ascorbate and glutathione and the levels of superoxide dismutase, ascorbate peroxidase, and catalase. However, antioxidant enzymes and antioxidant capacity of rice seedling were decreased by 0.2mM Ce(4+) treatment, indicating that higher content of Ce(4+) damaged the mechanism of defense responses and emerged the peroxidation of membrane lipids. These results will help us to understand the mechanism of Ce(4+) on rice and concern about its environmental impact in agriculture.

  14. Trace elements and antioxidant enzymes in extremely low birthweight infants.

    PubMed

    Loui, Andrea; Raab, Andrea; Maier, Rolf F; Brätter, Peter; Obladen, Michael

    2010-04-01

    Oxygen radicals are believed to contribute to typical diseases of prematurity, such as bronchopulmonary dysplasia (BPD), intraventricular haemorrhage (IVH), retinopathy of prematurity (ROP) and necrotising enterocolitis (NEC). Our aim was to investigate whether these disorders are associated with disturbances in antioxidant enzyme activities and with low trace elements, which are co-factors of antioxidant enzymes. 209 infants with birthweight less than 1000g were enrolled into a European multicentre randomised erythropoietin (rhEPO) trial; 155 developed one or more of the above mentioned diseases. We analysed Zn, Cu, Fe, Se in plasma and red blood cells (RBCs), superoxide dismutase (CuZn-SOD), glutathione peroxidase (GSH-Px), and catalase (CAT) in RBCs on the 3rd and 68th day of life. Zn, Fe, Se in plasma, and Se in RBCs decreased (p<0.01), and Zn in RBC (p<0.001), CuZn-SOD (p<0.01) and CAT increased (p<0.05), whereas GSH-Px remained unchanged. No differences were observed between the rhEPO and control groups. Antioxidant enzyme activities did not correlate with gestational age. In infants with BPD, IVH, ROP, or NEC, CuZn-SOD and CAT (p<0.05) were higher at day 68 than in infants without these diseases. CuZn-SOD and GSH-Px at 3 days and CuZn-SOD at 68 days correlated positively (p<0.05) with the duration of oxygen treatment. In conclusion, in ELBW infants, trace element concentrations decreased over the first 10 weeks of life. Lower trace element concentrations, did not affect the activities of CuZn-SOD, GSH-Px, and CAT. Typical diseases of prematurity were not associated with decreased antioxidant enzyme activities.

  15. DNA sequence determinants of nuclear protein binding to the c-Ha-ras antioxidant/electrophile response element in vascular smooth muscle cells: identification of Nrf2 and heat shock protein 90 beta as heterocomplex components.

    PubMed

    Miller, Kimberly P; Ramos, Kenneth S

    2005-01-01

    The antioxidant/electrophile response element (ARE/EpRE) is a cis-acting element involved in redox regulation of c-Ha-ras gene. Protein binding to the ARE/EpRE may be credited to deoxyribonucleic acid sequence; therefore, studies were conducted to evaluate the influence of internal and flanking regions to the 10-bp human c-Ha-ras ARE/EpRE core (hHaras10) on nuclear protein binding in oxidant-treated vascular smooth muscle cells. A protein doublet bound to an extended oligonucleotide comprising the ARE/EpRE core in genomic context (hHaras27), whereas a single complex bound to hHarasl0. Protein binding involved specific interactions of 25- and 23-kDa proteins with hHarasl0, and binding of 80-, 65-, and 55-kDa proteins to hHaras27. Competition assays with hNQO1 and rGSTA2 confirmed the specificity of deoxyribonucleic acid-protein interactions and indicated preferred binding of p25 and p23 to the c-Ha-ras ARE/EpRE. "NNN" sequences within the core afforded unique protein-binding profiles to the c-Ha-ras ARE/EpRE. In addition, Nrf2 and heat shock protein 90beta (p80) were identified as components of the c-Ha-ras ARE/EpRE heterocomplex. We conclude that both internal bases and flanking sequences regulate nuclear protein recruitment and complex assembly on the c-Ha-ras ARE/EpRE.

  16. Total antioxidant response in patients with schizophrenia.

    PubMed

    Ustundag, Bilal; Atmaca, Murad; Kirtas, Ozlem; Selek, Sahabettin; Metin, Kerem; Tezcan, Ertan

    2006-08-01

    There is a large amount of convincing data demonstrating that reactive oxygen species (ROS) are involved in initiation and development of many different forms of neuropsychiatric disorders. The levels of oxidants and antioxidants in schizophrenia have been evaluated. However, measurements of total antioxidant response (TAR) were not evaluated up to now. Therefore, the objectives of this study are to investigate plasma TAR levels in schizophrenia subtypes. A total of 76 patients with schizophrenia and 25 healthy volunteers were included in the study. Positive and Negative Syndrome Scale (SANS and SAPS, respectively) were applied to patients. TAR values were determined in the plasma of normal healthy controls and patients with schizophrenia. Plasma TAR levels of each schizophrenia subtype were significantly lower than healthy controls (P < 0.01 for disorganized, residual and undifferentiated subtypes and P < 0.01 for paranoid subtype). When intragroup comparisons were performed, paranoid subtype had higher plasma TAR levels compared to other subtypes (P < 0.01). Accordingly, as a whole group, patients with schizophrenia had lower plasma TAR levels compared to controls. Plasma TAR levels were significantly and negatively correlated with SANS scores, and duration of illness was evaluated but not related to other parameters. Consequently, the present study further emphasizes the growing consideration that free radical damage may have an important etiopathogenetic role on the development of schizophrenia and suggests that decreased plasma total antioxidant levels may be related to the progression of illness.

  17. Soy isoflavones increase quinone reductase in hepa-1c1c7 cells via estrogen receptor beta and nuclear factor erythroid 2-related factor 2 binding to the antioxidant response element.

    PubMed

    Froyen, Erik B; Steinberg, Francene M

    2011-09-01

    Soy protein and isoflavones (genistein and daidzein) have been demonstrated to increase quinone reductase (QR) activity, protein, and mRNA in animal and cell culture models. However, their mechanism of action has not been completely characterized. Additionally, it has not been determined if equol, a daidzein metabolite, can modulate QR activity and expression. Estrogen receptor beta (ERβ) is thought to be involved in stimulating QR gene transcription by anti-estrogens and phytoestrogens, along with nuclear factor erythroid 2-related factor 2 (Nrf2). This study tested the hypothesis that genistein, daidzein and equol increase quinone reductase activity, protein and mRNA via ERβ and Nrf2 binding to the QR antioxidant response element (ARE). QR expression and activity were determined using TaqMan polymerase chain reaction, protein immunoblots and activity assays. Molecular events were investigated using luciferase reporter gene assays and chromatin immunoprecipitation (ChIP). Hepa-1c1c7 cells were treated with control [0.1% (v:v) dimethyl sulfoxide (DMSO)]; 1 μmol/L β-naphthoflavone (positive control); 5 μmol/L resveratrol (ChIP positive control for ERβ binding) and 1, 5 and 25 μmol/L genistein, daidzein or equol. Treatment durations were 1 h (ChIP), 24 h (mRNA and luciferase assays) and 24 and 48 h (protein and activity). Genistein, daidzein and equol increased QR activity, protein and mRNA, with daidzein and equol having more of an impact at physiologic concentrations (1 and 5 μmol/L) compared to genistein. Furthermore, the study results demonstrate that genistein, daidzein and equol interact with the QR ARE and that daidzein and equol act via both ERβ and Nrf2 binding strongly to the QR ARE.

  18. Profiles of antioxidant/electrophile response element (ARE/EpRE) nuclear protein binding and c-Ha-ras transactivation in vascular smooth muscle cells treated with oxidative metabolites of benzo[a]pyrene.

    PubMed

    Miller, K P; Chen, Y H; Hastings, V L; Bral, C M; Ramos, K S

    2000-11-01

    Activation of nuclear protein binding to the antioxidant/electrophile response element (ARE/EpRE) by benzo[a]pyrene (BaP) in vascular smooth muscle cells (vSMCs) is associated with transcriptional deregulation of c-Ha-ras. This response may be mediated by oxidative intermediates of BaP generated during the course of cellular metabolism. To test this hypothesis, the profile of ARE/EpRE protein binding and transactivation elicited by BaP was compared with that of 3-hydroxy BaP (3-OH BaP) (0.03 to 3.0 microM), BaP 7,8-dihydrodiol (BaP 7,8-diol) (0.03 to 3.0 microM), BaP 3,6-quinone (BaP 3,6-Q) (0.0003 to 3.0 microM), and H(2)O(2) (25 to 100 microM). Specific protein binding to the consensus c-Ha-ras ARE/EpRE was observed in vSMCs treated with all BaP metabolites at concentrations considerably lower than those required for the parent compound. H(2)O(2), a by-product of BaP 3,6-Q redox cycling, also increased binding to the ARE/EpRE. Treatment of vSMCs with oxidative BaP metabolites or H(2)O(2) transactivated the c-Ha-ras promoter in all instances, but the response was consistently half of the maximal induction elicited by BaP. Similar proteins cross-linked specifically to the consensus c-Ha-ras ARE/EpRE sequence in cells treated with BaP or its oxidative intermediates. The protein binding profile in the c-Ha-ras promoter was similar to that in the NADPH:quinone reductase gene (NQO(1)) and the glutathione S-transferase Ya gene (GSTYa) promoters, but the relative abundance of individual complexes was promoter-specific. We conclude that oxidative intermediates of BaP mediate activation of nuclear protein binding to ARE/EpRE and contribute to transcriptional de-regulation of c-Ha-ras in vSMCs.

  19. Critical Evaluation of Ayurvedic Plants for Stimulating Intrinsic Antioxidant Response

    PubMed Central

    Shukla, Sunil Dutt; Bhatnagar, Maheep; Khurana, Sukant

    2012-01-01

    Oxidative damage caused by free radicals plays an important role in the causation and progression of many diseases, including aging. Free-radical damage is countered by many mechanisms, including both active antioxidant enzymatic activity in our body and passive antioxidants. Antioxidant response of our body can accommodate increased oxidative damage in diseased states to a level but beyond that level, additional antioxidants are required to combat the increased stress. Apart from the regular dietary sources of antioxidants, many traditional herbal medicines demonstrate a potential to boost antioxidant activity. Rasayana chikitsa that deals with rejuvenation and revitalization is a branch of the Indian traditional medical system of ayurveda. We review some select herbs described in rasayana chikitsa that have been assessed by modern means for stimulating intrinsic antioxidant responses in humans. A critical evaluation of rasayana chikitsa will likely provide urgently needed, actual stimulants of our physiological antioxidant responses and not just more passive antioxidants to add to an already large catalog. PMID:22855669

  20. Antioxidant responses of wheat plants under stress

    PubMed Central

    Caverzan, Andréia; Casassola, Alice; Brammer, Sandra Patussi

    2016-01-01

    Abstract Currently, food security depends on the increased production of cereals such as wheat (Triticum aestivum L.), which is an important source of calories and protein for humans. However, cells of the crop have suffered from the accumulation of reactive oxygen species (ROS), which can cause severe oxidative damage to the plants, due to environmental stresses. ROS are toxic molecules found in various subcellular compartments. The equilibrium between the production and detoxification of ROS is sustained by enzymatic and nonenzymatic antioxidants. In the present review, we offer a brief summary of antioxidant defense and hydrogen peroxide (H2O2) signaling in wheat plants. Wheat plants increase antioxidant defense mechanisms under abiotic stresses, such as drought, cold, heat, salinity and UV-B radiation, to alleviate oxidative damage. Moreover, H2O2 signaling is an important factor contributing to stress tolerance in cereals. PMID:27007891

  1. Antioxidant responses and cellular adjustments to oxidative stress

    PubMed Central

    Espinosa-Diez, Cristina; Miguel, Verónica; Mennerich, Daniela; Kietzmann, Thomas; Sánchez-Pérez, Patricia; Cadenas, Susana; Lamas, Santiago

    2015-01-01

    Redox biological reactions are now accepted to bear the Janus faceted feature of promoting both physiological signaling responses and pathophysiological cues. Endogenous antioxidant molecules participate in both scenarios. This review focuses on the role of crucial cellular nucleophiles, such as glutathione, and their capacity to interact with oxidants and to establish networks with other critical enzymes such as peroxiredoxins. We discuss the importance of the Nrf2-Keap1 pathway as an example of a transcriptional antioxidant response and we summarize transcriptional routes related to redox activation. As examples of pathophysiological cellular and tissular settings where antioxidant responses are major players we highlight endoplasmic reticulum stress and ischemia reperfusion. Topologically confined redox-mediated post-translational modifications of thiols are considered important molecular mechanisms mediating many antioxidant responses, whereas redox-sensitive microRNAs have emerged as key players in the posttranscriptional regulation of redox-mediated gene expression. Understanding such mechanisms may provide the basis for antioxidant-based therapeutic interventions in redox-related diseases. PMID:26233704

  2. A systems biology perspective on Nrf2-mediated antioxidant response

    SciTech Connect

    Zhang Qiang; Pi Jingbo; Woods, Courtney G.; Andersen, Melvin E.

    2010-04-01

    Cells in vivo are constantly exposed to reactive oxygen species (ROS) generated endogenously and exogenously. To defend against the deleterious consequences of ROS, cells contain multiple antioxidant enzymes expressed in various cellular compartments to scavenge these toxic species. Under oxidative stresses, these antioxidant enzymes are upregulated to restore redox homeostasis. Such an adaptive response results from the activation of a redox-sensitive gene regulatory network mediated by nuclear factor E2-related factor 2. To more completely understand how the redox control system is designed by nature to meet homeostatic goals, we have examined the network from a systems perspective using engineering approaches. As with man-made control devices, the redox control system can be decomposed into distinct functional modules, including transducer, controller, actuator, and plant. Cells achieve specific performance objectives by utilizing nested feedback loops, feedforward control, and ultrasensitive signaling motifs, etc. Given that endogenously generated ROS are also used as signaling molecules, our analysis suggests a novel mode of action to explain oxidative stress-induced pathological conditions and diseases. Specifically, by adaptively upregulating antioxidant enzymes, oxidative stress may inadvertently attenuate ROS signals that mediate physiological processes, resulting in aberrations of cellular functions and adverse consequences. Lastly, by simultaneously considering the two competing cellular tasks-adaptive antioxidant defense and ROS signaling-we re-examine the premise that dietary antioxidant supplements is generally beneficial to human health. Our analysis highlights some possible adverse effects of these widely consumed antioxidants.

  3. Uncovering drug-responsive regulatory elements

    PubMed Central

    Luizon, Marcelo R; Ahituv, Nadav

    2016-01-01

    Nucleotide changes in gene regulatory elements can have a major effect on interindividual differences in drug response. For example, by reviewing all published pharmacogenomic genome-wide association studies, we show here that 96.4% of the associated single nucleotide polymorphisms reside in noncoding regions. We discuss how sequencing technologies are improving our ability to identify drug response-associated regulatory elements genome-wide and to annotate nucleotide variants within them. We highlight specific examples of how nucleotide changes in these elements can affect drug response and illustrate the techniques used to find them and functionally characterize them. Finally, we also discuss challenges in the field of drug-responsive regulatory elements that need to be considered in order to translate these findings into the clinic. PMID:26555224

  4. Antioxidant response of wheat roots to drought acclimation.

    PubMed

    Selote, Devarshi S; Khanna-Chopra, Renu

    2010-09-01

    Wheat (Triticum aestivum L.) seedlings of a drought-resistant cv. C306 were subjected to severe water deficit directly or through stress cycles of increasing intensity with intermittent recovery periods. The antioxidant defense in terms of redox metabolites and enzymes in root cells and mitochondria was examined in relation to membrane damage. Acclimated seedlings exhibited higher relative water content and were able to limit the accumulation of H(2)O(2) and membrane damage during subsequent severe water stress conditions. This was due to systematic up-regulation of superoxide dismutase, ascorbate peroxidase (APX), catalase, peroxidases, and ascorbate-glutathione cycle components at both the whole cell level as well as in mitochondria. In contrast, direct exposure of severe water stress to non-acclimated seedlings caused greater water loss, excessive accumulation of H(2)O(2) followed by elevated lipid peroxidation due to the poor antioxidant enzyme response particularly of APX, monodehydroascorbate reductase, dehydroascorbate reductase, glutathione reductase, and ascorbate-glutathione redox balance. Mitochondrial antioxidant defense was found to be better than the cellular defense in non-acclimated roots. Termination of stress followed by rewatering leads to a rapid enhancement in all the antioxidant defense components in non-acclimated roots, which suggested that the excess levels of H(2)O(2) during severe water stress conditions might have inhibited or down-regulated the antioxidant enzymes. Hence, drought acclimation conferred enhanced tolerance toward oxidative stress in the root tissue of wheat seedlings due to both reactive oxygen species restriction and well-coordinated induction of antioxidant defense.

  5. [Some indices of trace elements and antioxidant status in rats under chromic intoxication].

    PubMed

    Mikhailova, I V; Chesnokova, L A; Sharapova, N V; Smolyagin, A I; Krasikov, S I

    2014-01-01

    There was investigated the effect of chronic Cr (VI) on the content of chromium, iron, copper; zinc, nickel in the blood of rats and activity of antioxidant enzymes of erythrocytes in Wistar rats. The chromium concentration has been shown to increase multifold while the level of other metal is more or less declining. Also it was found a decrease in the activity of such antioxidant enzymes as superoxide dismutase, catalase, and the activation of the processes of free radical oxidation. Thus, it can be assumed that the effect of Cr (VI) is implemented via an imbalance of trace elements and the activation of the processes of free radical oxidation. PMID:25306707

  6. Influence of silicon on maize roots exposed to antimony - growth and antioxidative response.

    PubMed

    Vaculíková, Miroslava; Vaculík, Marek; Šimková, Lenka; Fialová, Ivana; Kochanová, Zuzana; Sedláková, Barbora; Luxová, Miroslava

    2014-10-01

    Pollution of antimony (Sb) raises a serious environmental problem. Although this non-essential element can be taken up by roots and accumulated in plant tissues in relatively high concentrations, there is still lack of knowledge about the effect of Sb on biochemical and metabolic processes in plants. It was shown that application of silicon (Si) can decrease the toxicity of other heavy metals and toxic elements in various plants. The aim of this study was to assess how Si influences the growth and antioxidative response of young Zea mays L. roots exposed to elevated concentrations of Sb. Antimony reduced the root growth and induced oxidative stress and activated antioxidant defense mechanisms in maize. Silicon addition to Sb treated roots decreased oxidative stress symptoms documented by lower lipid peroxidation, proline accumulation, and decreased activity of antioxidative enzymes (ascorbate peroxidase, EC 1.11.1.11; catalase, EC 1.11.1.6; and guaiacol peroxidase, EC 1.11.1.7). Although neither positive nor negative effect of Si has been observed on root length and biomass, changes in the oxidative response of plants exposed to Sb indicate a possible mitigation role of Si on Sb toxicity in plants.

  7. Status of trace elements and antioxidants in premenopausal and postmenopausal phase of life: a comparative study

    PubMed Central

    Ansar, Sabah; Alhefdhi, Tayef; Aleem, Ansari M

    2015-01-01

    The aim of the study was to determine the extent of free radical damage in the form of oxidative stress, the antioxidant status and correlate with trace element levels in postmenopausal females as compared to premenopausal females. Participants between the ages of 30-60 years were recruited for the study and status of antioxidant enzymes and trace metals level was determined. The serum Calcium (Ca) levels after menopause was higher than that of the premenopausal group (P<0.001). The changes in copper (Cu) and Zinc (Zn) between the groups were not significant (p>0.05). In postmenopausal women, antioxidant enzymes like superoxide dismutase (SOD) and glutathione peroxidase (GPX), catalase (CAT) significantly decreased (P<0.001) in postmenopausal women showing oxidative stress in the cells. Concentrations of vitamin-C pointed out a significant decrease (P<0.05) in postmenopausal women when compared with premenopausal women. In conclusion. PMID:26770597

  8. Antioxidants

    MedlinePlus

    Antioxidants are man-made or natural substances that may prevent or delay some types of cell damage. Antioxidants are found in many foods, including fruits and ... are also available as dietary supplements. Examples of antioxidants include Beta-carotene Lutein Lycopene Selenium Vitamin A ...

  9. Trace element water improves the antioxidant activity of buckwheat (Fagopyrum esculentum Moench) sprouts.

    PubMed

    Liu, Chia-Ling; Chen, Yih-Shyuan; Yang, Joan-Hwa; Chiang, Been-Huang; Hsu, Cheng-Kuang

    2007-10-31

    Buckwheat (Fagopyrum esculentum Moench) was grown in trace element water (TEW) (100, 200, 300, 400, and 500 ppm) and deionized water (DIW) to evaluate whether the beneficial effects of trace elements on the antioxidant activity could be accomplished with the supplement of TEW. At 300 ppm, TEW significantly increased the Cu, Zn, Mn, and Fe contents in buckwheat sprout but not the Se content. However, the levels of rutin, isoorientin, vitexin, and isovitexin did not differ between buckwheat sprouts grown in TEW and DIW. The ethanolic extract from buckwheat sprout grown in 300 ppm of TEW showed higher ferrous ion chelating activity and inhibitory activity toward lipid peroxidation than that grown in DIW. The extract in the TEW group also enhanced intracellular superoxide dismutase activity and lowered reactive oxygen species and superoxide anion in the human Hep G2 cell. It was concluded that TEW could increase the antioxidant activities of buckwheat sprouts.

  10. Differences in responsivity of original cupric reducing antioxidant capacity and cupric-bathocuproine sulfonate assays to antioxidant compounds.

    PubMed

    Çelik, S Esin; Ozyürek, Mustafa; Güçlü, Kubilay; Apak, Reşat

    2012-04-01

    The cupric reducing antioxidant capacity (CUPRAC) method using bathocuproine sulfonate (BCS) as cuprous-chelating ligand claims to be an efficient substitute for the conventional CUPRAC assay using neocuproine; however, differences in their physical chemistry give rise to significantly varying responsivities to antioxidant compounds. The antioxidant capacity due to β-carotene (in acetone or dichloromethane) was fully measurable by conventional CUPRAC but not at all by cupric-BCS assay. Furthermore, CUPRAC exhibits distinctly stronger responses than cupric-BCS to naringenin, α-tocopherol, and bilirubin.

  11. Effect of lipid peroxidation, antioxidants, macro minerals and trace elements on eczema.

    PubMed

    Amin, Mohammad Nurul; Liza, Kaniz Fatema; Sarwar, Md Shahid; Ahmed, Jamiuddin; Adnan, Md Tareek; Chowdhury, Manjurul Islam; Hossain, Mohammad Zahid; Islam, Mohammad Safiqul

    2015-09-01

    The exact etiology and pathogenesis of eczema are not yet fully understood, although different factors are considered as pathogenic mechanisms in the development of eczema. Our study was designed to determine extent of serum lipid peroxidation, antioxidants, macro minerals and trace elements in patients with eczema, and thereby, find any pathophysiological correlation. The study was conducted as a case-control study with 65 eczema patients as cases and 65 normal healthy individuals as controls. Lipid peroxidation was assessed by measuring the serum level of malondialdehyde (MDA). Antioxidants- vitamin A and E concentration was determined by RP-HPLC method whereas vitamin C was evaluated for serum ascorbic acid by UV spectrophotometric method. Serum macro minerals (Na, K, Ca) and trace elements (Zn, Fe) were determined by Atomic Absorption Spectroscopy (AAS). This study found significantly higher level of MDA (p < 0.001) and lower level of antioxidants (p < 0.05) in patients in comparison to the control subjects. Analysis of serum macro minerals (Na, K and Ca) and trace elements (Zn, Fe) found that the mean values of Na, K, Ca, Zn and Fe were 2771.60 ± 75.64, 66.33 ± 3.03, 48.41 ± 2.50, 0.30 ± 0.02 and 0.29 ± 0.009 mg/L for the patient group and 3284.81 ± 34.51, 162.18 ± 3.72, 87.66 ± 2.10, 0.75 ± 0.06 and 0.87 ± 0.06 mg/L for the control group, accordingly. There was a significant difference for all the minerals between the patients and controls (p < 0.001). This study suggests a strong association between the pathogenesis of eczema with the elevated level of MDA and depleted level of antioxidants, macro minerals, and trace elements.

  12. Antioxidant value and element content in some tinctures used in medication.

    PubMed

    Szentmihályi, Klára; Varga, Ilona Szöllősi; Gergely, Anita; Rábai, Mária; Then, Mária

    2015-09-01

    Tinctures are almost the oldest medicines and their use is substantial in the medication nowadays as well. The antioxidant values by ferric reducing/antioxidant power (FRAP) method and element content by inductively coupled plasma optical emission spectrometry (ICP-OES) were investigated in some tinctures official in the VII. and VIII. Pharmacopoeia Hungarica. The highest FRAP values were found for volatile oil containing Tinctura Aurantii amari epicarpii et mesocarpii, Tinctura Amara and Tinctura Valerianae (764.54 ± 19.90; 757.37 ± 14.46; 826.40 ± 5.89 µmol l⁻¹, respectively). The correlations between the FRAP values and dilution with different alcohol content in Tinctura Chinae, Tinctura Ipecacuanhae normata and Tinctura Strychni were also investigated. Remarkable differences were found between the element concentrations in the different tinctures. The element contents in tinctures are not so high in absolute values nevertheless the presence of essential selenium, zinc, manganese and copper is important since they have key role in the antioxidant system. The common feature of the tinctures seems to be the lithium content. The Ca to Mg concentration ratio was found to be shifted towards magnesium in some of the tinctures that can show a higher Mg absorption which could affect against the proinflammatoric processes in the cases of gastrointestinal diseases. PMID:26344025

  13. Increased oxidative stress and impaired antioxidant response in Lafora disease.

    PubMed

    Romá-Mateo, Carlos; Aguado, Carmen; García-Giménez, José Luis; Ibáñez-Cabellos, José Santiago; Seco-Cervera, Marta; Pallardó, Federico V; Knecht, Erwin; Sanz, Pascual

    2014-10-01

    Lafora Disease (LD, OMIM 254780, ORPHA501) is a fatal neurodegenerative disorder characterized by the presence of glycogen-like intracellular inclusions called Lafora bodies and caused, in the vast majority of cases, by mutations in either EPM2A or EPM2B genes, encoding respectively laforin and malin. In the last years, several reports have revealed molecular details of these two proteins and have identified several processes affected in LD, but the pathophysiology of the disease still remains largely unknown. Since autophagy impairment has been reported as a characteristic treat in both Lafora disease cell and animal models, and as there is a link between autophagy and mitochondrial performance, we sought to determine if mitochondrial function could be altered in those models. Using fibroblasts from LD patients, deficient in laforin or malin, we found mitochondrial alterations, oxidative stress and a deficiency in antioxidant enzymes involved in the detoxification of reactive oxygen species (ROS). Similar results were obtained in brain tissue samples from transgenic mice deficient in either the EPM2A or EPM2B genes. Furthermore, in a proteomic analysis of brain tissue obtained from Epm2b-/- mice, we observed an increase in a modified form of peroxirredoxin-6, an antioxidant enzyme involved in other neurological pathologies, thus corroborating an alteration of the redox condition. These data support that oxidative stress produced by an increase in ROS production and an impairment of the antioxidant enzyme response to this stress play an important role in development of LD. PMID:26461389

  14. Nitric oxide, antioxidants and prooxidants in plant defence responses

    PubMed Central

    Groß, Felicitas; Durner, Jörg; Gaupels, Frank

    2013-01-01

    In plant cells the free radical nitric oxide (NO) interacts both with anti- as well as prooxidants. This review provides a short survey of the central roles of ascorbate and glutathione—the latter alone or in conjunction with S-nitrosoglutathione reductase—in controlling NO bioavailability. Other major topics include the regulation of antioxidant enzymes by NO and the interplay between NO and reactive oxygen species (ROS). Under stress conditions NO regulates antioxidant enzymes at the level of activity and gene expression, which can cause either enhancement or reduction of the cellular redox status. For instance chronic NO production during salt stress induced the antioxidant system thereby increasing salt tolerance in various plants. In contrast, rapid NO accumulation in response to strong stress stimuli was occasionally linked to inhibition of antioxidant enzymes and a subsequent rise in hydrogen peroxide levels. Moreover, during incompatible Arabidopsis thaliana-Pseudomonas syringae interactions ROS burst and cell death progression were shown to be terminated by S-nitrosylation-triggered inhibition of NADPH oxidases, further highlighting the multiple roles of NO during redox-signaling. In chemical reactions between NO and ROS reactive nitrogen species (RNS) arise with characteristics different from their precursors. Recently, peroxynitrite formed by the reaction of NO with superoxide has attracted much attention. We will describe putative functions of this molecule and other NO derivatives in plant cells. Non-symbiotic hemoglobins (nsHb) were proposed to act in NO degradation. Additionally, like other oxidases nsHb is also capable of catalyzing protein nitration through a nitrite- and hydrogen peroxide-dependent process. The physiological significance of the described findings under abiotic and biotic stress conditions will be discussed with a special emphasis on pathogen-induced programmed cell death (PCD). PMID:24198820

  15. Finite element simulation of pipe dynamic response

    SciTech Connect

    Slagis, G.C.; Litton, R.W.

    1996-12-01

    Nonlinear finite element dynamic analyses of the response of a pipe span to controlled-displacement, sinusoidal vibration have been performed. The objective of this preliminary study is to compare strain and acceleration response data to those generated by Beaney in the Berkeley Nuclear Laboratories experiments. Results for an unpressurized, 5 Hz, carbon steel pipe are in good agreement with the experiments. Hence, it appears that analytical simulation will be useful to assess seismic margins. Recommendations for additional studies are provided. The analyses confirm the test results--dynamic response is greatly attenuated by material plasticity. Analytical strains and accelerations are about 30% higher than test data. There are several possible explanations for the differences. To assess the effect of frequency on response, the length of the pipe span was increased. Analysis of the longer, 2 Hz, pipe span shows significantly greater cyclic strains than the 5 Hz span at the same input excitation levels.

  16. Tandem antioxidant enzymes confer synergistic protective responses in experimental filariasis.

    PubMed

    Prince, P R; Madhumathi, J; Anugraha, G; Jeyaprita, P J; Reddy, M V R; Kaliraj, P

    2014-12-01

    Helminth parasites use antioxidant defence strategies for survival during oxidative stress due to free radicals in the host. Accordingly, tissue-dwelling filarial parasites counteract host responses by releasing a number of antioxidants. Targeting these redox regulation proteins together, would facilitate effective parasite clearance. Here, we report the combined effect of protective immune responses trigged by recombinant Wuchereria bancrofti thioredoxin (WbTRX) and thioredoxin peroxidase (WbTPX) in an experimental filarial model. The expression of WbTRX and WbTPX in different stages of the parasite and their cross-reactivity were analysed by enzyme-linked immunosorbent assay (ELISA). The immunogenicity of recombinant proteins and their protective efficacy were studied in animal models when immunized in single or cocktail mode. The antigens showed cross-reactive epitopes and induced high humoral and cellular immune responses in mice. Further, parasite challenge against Brugia malayi L3 larvae in Mastomys coucha conferred significant protection of 57% and 62% against WbTRX and WbTPX respectively. The efficacy of L3 clearance was significantly higher (71%) (P <  0.001) when the antigens were immunized together, showing a synergistic effect in multiple-mode vaccination. Hence, the study suggests WbTRX and WbTPX to be attractive vaccine candidates when immunized together and provides a tandem block for parasite elimination in the control of lymphatic filariasis.

  17. Dimerization Controls Marburg Virus VP24-dependent Modulation of Host Antioxidative Stress Responses.

    PubMed

    Johnson, Britney; Li, Jing; Adhikari, Jagat; Edwards, Megan R; Zhang, Hao; Schwarz, Toni; Leung, Daisy W; Basler, Christopher F; Gross, Michael L; Amarasinghe, Gaya K

    2016-08-28

    Marburg virus (MARV), a member of the Filoviridae family that also includes Ebola virus (EBOV), causes lethal hemorrhagic fever with case fatality rates that have exceeded 50% in some outbreaks. Within an infected cell, there are numerous host-viral interactions that contribute to the outcome of infection. Recent studies identified MARV protein 24 (mVP24) as a modulator of the host antioxidative responses, but the molecular mechanism remains unclear. Using a combination of biochemical and mass spectrometry studies, we show that mVP24 is a dimer in solution that directly binds to the Kelch domain of Kelch-like ECH-associated protein 1 (Keap1) to regulate nuclear factor (erythroid-derived 2)-like 2 (Nrf2). This interaction between Keap1 and mVP24 occurs through the Kelch interaction loop (K-Loop) of mVP24 leading to upregulation of antioxidant response element transcription, which is distinct from other Kelch binders that regulate Nrf2 activity. N-terminal truncations disrupt mVP24 dimerization, allowing monomeric mVP24 to bind Kelch with higher affinity and stimulate higher antioxidative stress response element (ARE) reporter activity. Mass spectrometry-based mapping of the interface revealed overlapping binding sites on Kelch for mVP24 and the Nrf2 proteins. Substitution of conserved cysteines, C209 and C210, to alanine in the mVP24 K-Loop abrogates Kelch binding and ARE activation. Our studies identify a shift in the monomer-dimer equilibrium of MARV VP24, driven by its interaction with Keap1 Kelch domain, as a critical determinant that modulates host responses to pathogenic Marburg viral infections. PMID:27497688

  18. Preparation and antioxidant capacity of element selenium nanoparticles sol-gel compounds.

    PubMed

    Bai, Yan; Qin, Biyin; Zhou, Yanhui; Wang, Yudong; Wang, Zi; Zheng, Wenjie

    2011-06-01

    This paper reported the preparation and antioxidant capacities of element selenium nanoparticles (nanoSe(0))-ascorbic acid (Vc) sol and nanSe(0)/Vc/selenocystine (SeCys) sol-gel compounds. NanoSe(0)-Vc sol was prepared by reduction of selenious dioxide (SeO2) with Vc. In the nanoSe(0)-Vc sol, highly concentrated Vc was also used as a modifier to modulate the diameter of Se(0) nanoparticles in the liquid phase. Then excellent nanoSe(0) sol-gel compounds were obtained by adding SeCys into the nanoSe(0)-Vc sol. The structure of the nanoSe(0)/Vc/SeCys sol-gel compounds was defined, which was constructed via C-Se, Se-H and O=C-Se valences and by interaction between SeCys and Vc via peptide bonds, esterification and dehydration. The antioxidant capacities of the nanoSe(0)-Vc sol and the nanoSe(0)Vc/SeCys sol-gel compounds were estimated by oxygen radical absorption capacity (ORAC) assay. The nanoSe(0)/Vc/SeCys sol-gel compounds possessed a strong antioxidant capacity due to forming the perfect three-dimensional (3D) frameworks structure. The results suggested that the nanoSe(0)-Vc sol and the nanoSe(0)Vc/SeCys sol-gel compounds might be potential medicine, especially antioxidant.

  19. A potential link among antioxidant enzymes, histopathology and trace elements in canine visceral leishmaniasis

    PubMed Central

    Souza, Carolina C; Barreto, Tatiane de O; da Silva, Sydnei M; Pinto, Aldair W J; Figueiredo, Maria M; Ferreira Rocha, Olguita G; Cangussú, Silvia D; Tafuri, Wagner L

    2014-01-01

    Canine visceral leishmaniasis (CVL) is a severe and fatal systemic chronic inflammatory disease. We investigated the alterations in, and potential associations among, antioxidant enzymes, trace elements and histopathology in CVL. Blood and tissue levels of Cu-Zn superoxide dismutase, catalase and glutathione peroxidase were measured in mixed-breed dogs naturally infected with Leishmania infantum chagasi, symptomatic (n = 19) and asymptomatic (n = 11). Serum levels of copper, iron, zinc, selenium and nitric oxide, and plasma lipid peroxidation were measured. Histological and morphometric analyses were conducted of lesions in liver, spleen and lymph nodes. We found lower blood catalase and glutathione peroxidase activity to be correlated with lower iron and selenium respectively. However, higher activity of Cu-Zn superoxide dismutase was not correlated with the increase in copper and decreased in zinc observed in infected animals compared to controls. Organ tissue was characterized by lower enzyme activity in infected dogs than in controls, but this was not correlated with trace elements. Lipid peroxidation was higher in symptomatic than in asymptomatic and control dogs and was associated with lesions such as chronic inflammatory reaction, congestion, haemosiderin and fibrosis. Systemic iron deposition was observed primarily in the symptomatic dogs showing a higher tissue parasite load. Dogs with symptomatic CVL displayed enhanced LPO and Fe tissue deposition associated with decreased levels of antioxidant enzymes. These results showed new points in the pathology of CVL and might open new treatment perspectives associated with antioxidants and the role of iron in the pathogenesis of CVL. PMID:24766461

  20. Induction of human fetal hemoglobin via the NRF2 antioxidant response signaling pathway

    PubMed Central

    Macari, Elizabeth R.

    2011-01-01

    Although hematopoietic stem cell transplantation and gene therapy have the potential to cure β-thalassemia and sickle cell disease, they are not currently available to most people with these diseases. In the near term, pharmacologic induction of fetal hemoglobin (HbF) may offer the best possibility for safe, effective, and widely available therapy. In an effort to define new pathways for targeted drug development for HbF induction, we evaluated the nuclear factor erythroid 2–related factor 2 (NRF2) antioxidant response element signaling pathway. We found that 3 well-known activators of this pathway increased γ-globin mRNA at nontoxic doses in K562 cells. Tert-butylhydroquinone (tBHQ), the most active of these compounds, increased cellular levels and nuclear translocation of NRF2 and binding of NRF2 to the γ-globin promoter. siRNA knockdown of NRF2 inhibited γ-globin induction by tBHQ. When tested in human primary erythroid cells, tBHQ induced NRF2 binding to the γ-globin promoter, increased γ-globin mRNA and HbF, and suppressed β-globin mRNA and HbA, resulting in a > 3-fold increase in the percentage of HbF. These results suggest that drugs that activate the NRF2/antioxidant response element signaling pathway have the potential to induce therapeutic levels of HbF in people with β-hemoglobinopathies. PMID:21464371

  1. Induction of human fetal hemoglobin via the NRF2 antioxidant response signaling pathway.

    PubMed

    Macari, Elizabeth R; Lowrey, Christopher H

    2011-06-01

    Although hematopoietic stem cell transplantation and gene therapy have the potential to cure β-thalassemia and sickle cell disease, they are not currently available to most people with these diseases. In the near term, pharmacologic induction of fetal hemoglobin (HbF) may offer the best possibility for safe, effective, and widely available therapy. In an effort to define new pathways for targeted drug development for HbF induction, we evaluated the nuclear factor erythroid 2-related factor 2 (NRF2) antioxidant response element signaling pathway. We found that 3 well-known activators of this pathway increased γ-globin mRNA at nontoxic doses in K562 cells. Tert-butylhydroquinone (tBHQ), the most active of these compounds, increased cellular levels and nuclear translocation of NRF2 and binding of NRF2 to the γ-globin promoter. siRNA knockdown of NRF2 inhibited γ-globin induction by tBHQ. When tested in human primary erythroid cells, tBHQ induced NRF2 binding to the γ-globin promoter, increased γ-globin mRNA and HbF, and suppressed β-globin mRNA and HbA, resulting in a > 3-fold increase in the percentage of HbF. These results suggest that drugs that activate the NRF2/antioxidant response element signaling pathway have the potential to induce therapeutic levels of HbF in people with β-hemoglobinopathies.

  2. Antioxidant Responses and NRF2 in Synergistic Developmental Toxicity of PAHs in Zebrafish

    PubMed Central

    Timme-Laragy, Alicia R.; Van Tiem, Lindsey A.; Linney, Elwood A.; Di Giulio, Richard T.

    2009-01-01

    Early piscine life stages are sensitive to polycyclic aromatic hydrocarbon (PAH) exposure, which can cause pericardial effusion and craniofacial malformations. We previously reported that certain combinations of PAHs cause synergistic developmental toxicity, as observed with coexposure to the aryl hydrocarbon receptor agonist β-naphthoflavone (BNF) and cytochrome P4501A inhibitor α-naphthoflavone (ANF). Herein, we hypothesized that oxidative stress is a component of this toxicity. We examined induction of antioxidant genes in zebrafish embryos (Danio rerio) exposed to BNF or ANF individually, a BNF + ANF combination, and a prooxidant positive control, tert-butylhydroperoxide (tBOOH). We measured total glutathione (GSH) and attempted to modulate deformities using the GSH synthesis inhibitor L-buthionine (S,R)-sulfoximine (BSO) and increase GSH pools with N-acetyl cysteine (NAC). In addition, we used a morpholino to knockdown expression of the antioxidant response element transcription factor NRF2 to determine if this would alter gene expression or increase deformity severity. BNF + ANF coexposure significantly increased expressions of superoxide dismutase 1 and 2, glutathione peroxidase 1, pi class glutathione-s-transferase, and glutamate cysteine-ligase to a greater extent than tBOOH, BNF, or ANF alone. BSO pretreatment decreased some GSH levels, but did not worsen deformities, nor did NAC diminish toxicity. Knockdown of NRF2 increased mortality following tBOOH challenge, prevented significant upregulation of antioxidant genes following both tBOOH and BNF + ANF exposures, and exacerbated BNF + ANF–related deformities. Collectively, these findings demonstrate that antioxidant responses are a component of PAH synergistic developmental toxicity and that NRF2 is protective against prooxidant and PAH challenges during development. PMID:19233942

  3. Antioxidant Response of Chronic Wounds to Hyperbaric Oxygen Therapy

    PubMed Central

    Sureda, Antoni; Batle, Juan M.; Martorell, Miquel; Capó, Xavier; Tejada, Silvia; Tur, Josep A.; Pons, Antoni

    2016-01-01

    We analyzed the effects of the clinical hyperbaric oxygen therapy (HBOT) on the plasma antioxidant response and levels of endothelin-1, Interleukine-6 (IL-6) and vascular endothelial growth factor (VEGF) in patients with chronic wounds (20.2±10.0 months without healing). They received 20 HBOT sessions (five sessions/week), and blood samples were obtained at sessions 1, 5 and 20 before and 2 hours after the HBOT. An additional blood sample was collected 1 month after wound recovery. Serum creatine kinase activity decreased progressively in accordance with the wound healing. Plasma catalase activity significantly increased after the first and fifth sessions of HBOT. Plasma myeloperoxidase activity reported significantly lower values after sessions. Plasma VEGF and IL-6 increased after sessions. Endothelin-1 levels were progressively decreasing during the HBOT, being significant at the session 20. Plasma malondialdehyde concentration was significantly reduced at the last session. Both creatine kinase activity and malondialdehyde levels were maintained lower 1 month after wound recovery respect to initial values. In conclusion, HBOT enhanced the plasma antioxidant defenses and may contribute to activate the healing resolution, angiogenesis and vascular tone regulation by increasing the VEGF and IL-6 release and the endothelin-1 decrease, which may be significant factors in stimulating wound healing. PMID:27654305

  4. Antioxidant response of soybean seedlings to joint stress of lanthanum and acid rain.

    PubMed

    Liang, Chanjuan; Wang, Weimin

    2013-11-01

    Excess of rare earth elements in soil can be a serious environmental stress on plants, in particular when acid rain coexists. To understand how such a stress affects plants, we studied antioxidant response of soybean leaves and roots exposed to lanthanum (0.06, 0.18, and 0.85 mmol L(-1)) under acid rain conditions (pH 4.5 and 3.0). We found that low concentration of La3+ (0.06 mmol L(-1)) did not affect the activity of antioxidant enzymes (catalase and peroxidase) whereas high concentration of La3+ (≥0.18 mmol L(-1)) did. Compared to treatment with acid rain (pH 4.5 and pH 3.0) or La3+ alone, joint stress of La3+ and acid rain affected more severely the activity of catalase and peroxidase, and induced more H2O2 accumulation and lipid peroxidation. When treated with high level of La3+ (0.85 mmol L(-1)) alone or with acid rain (pH 4.5 and 3.0), roots were more affected than leaves regarding the inhibition of antioxidant enzymes, physiological function, and growth. The severity of oxidative damage and inhibition of growth caused by the joint stress associated positively with La3+ concentration and soil acidity. These results will help us understand plant response to joint stress, recognize the adverse environmental impact of rare earth elements in acidic soil, and develop measures to eliminate damage caused by such joint stress.

  5. Antioxidant response of soybean seedlings to joint stress of lanthanum and acid rain.

    PubMed

    Liang, Chanjuan; Wang, Weimin

    2013-11-01

    Excess of rare earth elements in soil can be a serious environmental stress on plants, in particular when acid rain coexists. To understand how such a stress affects plants, we studied antioxidant response of soybean leaves and roots exposed to lanthanum (0.06, 0.18, and 0.85 mmol L(-1)) under acid rain conditions (pH 4.5 and 3.0). We found that low concentration of La3+ (0.06 mmol L(-1)) did not affect the activity of antioxidant enzymes (catalase and peroxidase) whereas high concentration of La3+ (≥0.18 mmol L(-1)) did. Compared to treatment with acid rain (pH 4.5 and pH 3.0) or La3+ alone, joint stress of La3+ and acid rain affected more severely the activity of catalase and peroxidase, and induced more H2O2 accumulation and lipid peroxidation. When treated with high level of La3+ (0.85 mmol L(-1)) alone or with acid rain (pH 4.5 and 3.0), roots were more affected than leaves regarding the inhibition of antioxidant enzymes, physiological function, and growth. The severity of oxidative damage and inhibition of growth caused by the joint stress associated positively with La3+ concentration and soil acidity. These results will help us understand plant response to joint stress, recognize the adverse environmental impact of rare earth elements in acidic soil, and develop measures to eliminate damage caused by such joint stress. PMID:23653318

  6. Benzo[a]pyrene affects Jurkat T cells in the activated state via the antioxidant response element dependent Nrf2 pathway leading to decreased IL-2 secretion and redirecting glutamine metabolism

    SciTech Connect

    Murugaiyan, Jayaseelan; Rockstroh, Maxie; Wagner, Juliane; Baumann, Sven; Schorsch, Katrin; Trump, Saskia; Lehmann, Irina; Bergen, Martin von; Tomm, Janina M.

    2013-06-15

    There is a clear evidence that environmental pollutants, such as benzo[a]pyrene (B[a]P), can have detrimental effects on the immune system, whereas the underlying mechanisms still remain elusive. Jurkat T cells share many properties with native T lymphocytes and therefore are an appropriate model to analyze the effects of environmental pollutants on T cells and their activation. Since environmental compounds frequently occur at low, not acute toxic concentrations, we analyzed the effects of two subtoxic concentrations, 50 nM and 5 μM, on non- and activated cells. B[a]P interferes directly with the stimulation process as proven by an altered IL-2 secretion. Furthermore, B[a]P exposure results in significant proteomic changes as shown by DIGE analysis. Pathway analysis revealed an involvement of the AhR independent Nrf2 pathway in the altered processes observed in unstimulated and stimulated cells. A participation of the Nrf2 pathway in the change of IL-2 secretion was confirmed by exposing cells to the Nrf2 activator tBHQ. tBHQ and 5 μM B[a]P caused similar alterations of IL-2 secretion and glutamine/glutamate metabolism. Moreover, the proteome changes in unstimulated cells point towards a modified regulation of the cytoskeleton and cellular stress response, which was proven by western blotting. Additionally, there is a strong evidence for alterations in metabolic pathways caused by B[a]P exposure in stimulated cells. Especially the glutamine/glutamate metabolism was indicated by proteome pathway analysis and validated by metabolite measurements. The detrimental effects were slightly enhanced in stimulated cells, suggesting that stimulated cells are more vulnerable to the environmental pollutant model compound B[a]P. - Highlights: • B[a]P affects the proteome of Jurkat T cells also at low concentrations. • Exposure to B[a]P (50 nM, 5 μM) did not change Jurkat T cell viability. • Both B[a]P concentrations altered the IL-2 secretion of stimulated cells.

  7. The level of elements and antioxidant activity of commercial dietary supplement formulations based on edible mushrooms.

    PubMed

    Stilinović, Nebojša; Škrbić, Biljana; Živančev, Jelena; Mrmoš, Nataša; Pavlović, Nebojša; Vukmirović, Saša

    2014-12-01

    Commercial preparations of Cordyceps sinensis, Ganoderma lucidum and Coprinus comatus mushroom marketed as healthy food supplements in Serbia were analyzed by atomic absorption spectrometry with a graphite furnace (GFAAS) for their element content. Antioxidant activity potential and total phenolics of the same mushrooms were determined. The element content of mushroom samples was in the range of 0.130-0.360 mg kg(-1) for lead (Pb), <0.03-0.46 mg kg(-1) for arsenic (As), 0.09-0.39 mg kg(-1) for cadmium (Cd), 98.14-989.18 mg kg(-1) for iron (Fe), 0.10-101.32 mg kg(-1) for nickel (Ni), 5.06-26.50 mg kg(-1) for copper (Cu), 0.20-0.70 mg kg(-1) for cobalt (Co), 1.74-136.33 mg kg(-1) for chromium (Cr) and 2.19-21.54 mg kg(-1) for manganese (Mn). In the tests for measuring the antioxidant activity, the methanolic extract of C. sinensis showed the best properties. The same was seen for the analysis of selected phenolic compounds; C. sinensis was found to have the highest content. Commercial preparations of C. sinensis and C. comatus can be considered to be safe and suitable food supplements included in well-balanced diets.

  8. The level of elements and antioxidant activity of commercial dietary supplement formulations based on edible mushrooms.

    PubMed

    Stilinović, Nebojša; Škrbić, Biljana; Živančev, Jelena; Mrmoš, Nataša; Pavlović, Nebojša; Vukmirović, Saša

    2014-12-01

    Commercial preparations of Cordyceps sinensis, Ganoderma lucidum and Coprinus comatus mushroom marketed as healthy food supplements in Serbia were analyzed by atomic absorption spectrometry with a graphite furnace (GFAAS) for their element content. Antioxidant activity potential and total phenolics of the same mushrooms were determined. The element content of mushroom samples was in the range of 0.130-0.360 mg kg(-1) for lead (Pb), <0.03-0.46 mg kg(-1) for arsenic (As), 0.09-0.39 mg kg(-1) for cadmium (Cd), 98.14-989.18 mg kg(-1) for iron (Fe), 0.10-101.32 mg kg(-1) for nickel (Ni), 5.06-26.50 mg kg(-1) for copper (Cu), 0.20-0.70 mg kg(-1) for cobalt (Co), 1.74-136.33 mg kg(-1) for chromium (Cr) and 2.19-21.54 mg kg(-1) for manganese (Mn). In the tests for measuring the antioxidant activity, the methanolic extract of C. sinensis showed the best properties. The same was seen for the analysis of selected phenolic compounds; C. sinensis was found to have the highest content. Commercial preparations of C. sinensis and C. comatus can be considered to be safe and suitable food supplements included in well-balanced diets. PMID:25294630

  9. Antioxidant response of Phragmites australis to Cu and Cd contamination.

    PubMed

    Rocha, A Cristina S; Almeida, C Marisa R; Basto, M Clara P; Vasconcelos, M Teresa S D

    2014-11-01

    Metals are known to induce oxidative stress in plant cells. Antioxidant thiolic compounds are known to play an important role in plants׳ defence mechanisms against metal toxicity but, regarding salt marsh plants, their role is still very poorly understood. In this work, the involvement of non-protein thiols (NPT), such as cysteine (Cys), reduced glutathione (GSH), oxidised glutathione (GSSG) and total acid-soluble SH compounds (total thiols), in the tolerance mechanisms of the marsh plant Phragmites australis against Cu and Cd toxicity was assessed. Specimens of this plant, freshly harvested in an estuarine salt marsh, were exposed, for 7 days, to rhizosediment soaked with the respective elutriate contaminated with Cu (0, 10 and 100 mg/L) or Cd (0, 1, 10 mg/L). In terms of NPT production, Cu and Cd contamination induced different responses in P. australis. The content of Cys increased in plant tissue after plant exposure to Cu, whereas Cd contamination led to a decrease in GSSG levels. In general, metal contamination did not cause a significant variation on GSH levels. Both metals influenced, to some extent, the production of other thiolic compounds. Despite the accumulation of considerable amounts of Cu and Cd in belowground tissues, no visible toxicity signs were observed. So, antioxidant thiolic compounds were probably involved in the mechanisms used by P. australis to alleviate metal toxicity. As P. australis is considered suitable for phytostabilising metal-contaminated sediments, understanding its tolerance mechanisms to toxic metals is important to optimise the conditions for applying this plant in phytoremediation procedures.

  10. Role of antioxidants and trace elements in health and immunity of transition dairy cows.

    PubMed

    Spears, Jerry W; Weiss, William P

    2008-04-01

    A number of antioxidants and trace minerals have important roles in immune function and may affect health in transition dairy cows. Vitamin E and beta-carotene are important cellular antioxidants. Selenium (Se) is involved in the antioxidant system via its role in the enzyme glutathione peroxidase. Inadequate dietary vitamin E or Se decreases neutrophil function during the perpariturient period. Supplementation of vitamin E and/or Se has reduced the incidence of mastitis and retained placenta, and reduced duration of clinical symptoms of mastitis in some experiments. Research has indicated that beta-carotene supplementation may enhance immunity and reduce the incidence of retained placenta and metritis in dairy cows. Marginal copper deficiency resulted in reduced neutrophil killing and decreased interferon production by mononuclear cells. Copper supplementation of a diet marginal in copper reduced the peak clinical response during experimental Escherichia coli mastitis. Limited research indicated that chromium supplementation during the transition period may increase immunity and reduce the incidence of retained placenta.

  11. Ionizing radiation, antioxidant response and oxidative damage: A meta-analysis.

    PubMed

    Einor, D; Bonisoli-Alquati, A; Costantini, D; Mousseau, T A; Møller, A P

    2016-04-01

    One mechanism proposed as a link between exposure to ionizing radiation and detrimental effects on organisms is oxidative damage. To test this hypothesis, we surveyed the scientific literature on the effects of chronic low-dose ionizing radiation (LDIR) on antioxidant responses and oxidative damage. We found 40 publications and 212 effect sizes for antioxidant responses and 288 effect sizes for effects of oxidative damage. We performed a meta-analysis of signed and unsigned effect sizes. We found large unsigned effects for both categories (0.918 for oxidative damage; 0.973 for antioxidant response). Mean signed effect size weighted by sample size was 0.276 for oxidative damage and -0.350 for antioxidant defenses, with significant heterogeneity among effects for both categories, implying that ionizing radiation caused small to intermediate increases in oxidative damage and small to intermediate decreases in antioxidant defenses. Our estimates are robust, as shown by very high fail-safe numbers. Species, biological matrix (tissue, blood, sperm) and age predicted the magnitude of effects for oxidative damage as well as antioxidant response. Meta-regression models showed that effect sizes for oxidative damage varied among species and age classes, while effect sizes for antioxidant responses varied among species and biological matrices. Our results are consistent with the description of mechanisms underlying pathological effects of chronic exposure to LDIR. Our results also highlight the importance of resistance to oxidative stress as one possible mechanism associated with variation in species responses to LDIR-contaminated areas. PMID:26851726

  12. Potential antioxidant response to coffee — A matter of genotype?

    PubMed Central

    Hassmann, Ute; Haupt, Larisa M.; Smith, Robert A.; Winkler, Swantje; Bytof, Gerhard; Lantz, Ingo; Griffiths, Lyn R.; Marko, Doris

    2014-01-01

    In a human intervention study, coffee combining natural green coffee bean constituents and dark roast products was identified as a genotype-dependent inducer of the Nrf2/ARE pathway, significantly affecting Nrf2 gene expression and downstream GST1A1 and UGT1A1 gene transcription. The observed transcriptional changes correlated with the presence of specific Nrf2 genotypes suggesting their influence on both Nrf2 and subsequent ARE-dependent GST1A1 and UGT1A1 transcription. While the presence of the − 653 SNP seems to be advantageous, resulting in higher Nrf2, GST1A1 and UGT1A1 gene transcription following coffee consumption, in contrast, the presence of the − 651 SNP significantly down-regulated the response to the study coffee. Furthermore, the presence of the B/B genotype in GST1A1 along with the frequency of the [TA]6/6 and [TA]7/7 polymorphisms in UGT1A1 appeared to significantly increase sensitivity toward coffee-induced gene transcription. This data suggests that when examining the role of the Nrf2/ARE pathway in the regulation of antioxidative and chemopreventive phase II efficacy, individual genotypes should be included when considering the potency of bioactive food/food constituents and their therapeutic potential. PMID:25606436

  13. Potential antioxidant response to coffee - A matter of genotype?

    PubMed

    Hassmann, Ute; Haupt, Larisa M; Smith, Robert A; Winkler, Swantje; Bytof, Gerhard; Lantz, Ingo; Griffiths, Lyn R; Marko, Doris

    2014-12-01

    In a human intervention study, coffee combining natural green coffee bean constituents and dark roast products was identified as a genotype-dependent inducer of the Nrf2/ARE pathway, significantly affecting Nrf2 gene expression and downstream GST1A1 and UGT1A1 gene transcription. The observed transcriptional changes correlated with the presence of specific Nrf2 genotypes suggesting their influence on both Nrf2 and subsequent ARE-dependent GST1A1 and UGT1A1 transcription. While the presence of the - 653 SNP seems to be advantageous, resulting in higher Nrf2, GST1A1 and UGT1A1 gene transcription following coffee consumption, in contrast, the presence of the - 651 SNP significantly down-regulated the response to the study coffee. Furthermore, the presence of the B/B genotype in GST1A1 along with the frequency of the [TA]6/6 and [TA]7/7 polymorphisms in UGT1A1 appeared to significantly increase sensitivity toward coffee-induced gene transcription. This data suggests that when examining the role of the Nrf2/ARE pathway in the regulation of antioxidative and chemopreventive phase II efficacy, individual genotypes should be included when considering the potency of bioactive food/food constituents and their therapeutic potential. PMID:25606436

  14. Potential antioxidant response to coffee - A matter of genotype?

    PubMed

    Hassmann, Ute; Haupt, Larisa M; Smith, Robert A; Winkler, Swantje; Bytof, Gerhard; Lantz, Ingo; Griffiths, Lyn R; Marko, Doris

    2014-12-01

    In a human intervention study, coffee combining natural green coffee bean constituents and dark roast products was identified as a genotype-dependent inducer of the Nrf2/ARE pathway, significantly affecting Nrf2 gene expression and downstream GST1A1 and UGT1A1 gene transcription. The observed transcriptional changes correlated with the presence of specific Nrf2 genotypes suggesting their influence on both Nrf2 and subsequent ARE-dependent GST1A1 and UGT1A1 transcription. While the presence of the - 653 SNP seems to be advantageous, resulting in higher Nrf2, GST1A1 and UGT1A1 gene transcription following coffee consumption, in contrast, the presence of the - 651 SNP significantly down-regulated the response to the study coffee. Furthermore, the presence of the B/B genotype in GST1A1 along with the frequency of the [TA]6/6 and [TA]7/7 polymorphisms in UGT1A1 appeared to significantly increase sensitivity toward coffee-induced gene transcription. This data suggests that when examining the role of the Nrf2/ARE pathway in the regulation of antioxidative and chemopreventive phase II efficacy, individual genotypes should be included when considering the potency of bioactive food/food constituents and their therapeutic potential.

  15. Organic extract contaminants from drinking water activate Nrf2-mediated antioxidant response in a human cell line.

    PubMed

    Wang, Shu; Zhang, Hao; Zheng, Weiwei; Wang, Xia; Andersen, Melvin E; Pi, Jingbo; He, Gengsheng; Qu, Weidong

    2013-05-01

    Traditional risk assessment methods face challenges in estimating risks from drinking waters that contain low-levels of large numbers of contaminants. Here, we evaluate the toxicity of organic contaminant (OC) extracts from drinking water by examining activation of nuclear factor E2-related factor 2 (Nrf2)-mediated antioxidant response. In HepG2 cells, the Nrf2-mediated antioxidant response-measured as Nrf2 protein accumulation, expression of antioxidant response element (ARE)-regulated genes and ARE-luciferase reporter gene assays were activated by OC extracts from drinking water sources that detected 25 compounds in 9 classification groups. Individual OCs induced oxidative stress at concentrations much higher than their environmental levels; however, mixtures of contaminants induced oxidative stress response at only 8 times the environmental levels. Additionally, a synthetic OC mixture prepared based on the contamination profiling of drinking water induced ARE activity to the same extent as the real-world mixture, reinforcing our conclusion that these mixture exposures produce responses relevant for human exposure situations. Our study tested the possibility of assessing toxicity of OCs of drinking water using a specific ARE-pathway measurement. This approach should be broadly useful in assisting risk assessment of mixed environmental exposure.

  16. Dimethyl fumarate modulation of immune and antioxidant responses: application to HIV therapy

    PubMed Central

    Gill, Alexander J.; Kolson, Dennis L.

    2013-01-01

    The persistence of chronic immune activation and oxidative stress in human immunodeficiency virus (HIV)-infected, antiretroviral drug-treated individuals are major obstacles to fully preventing HIV disease progression. The immune modulator and antioxidant dimethyl fumarate (DMF) is effective in treating immune-mediated diseases and it also has potential applications to limiting HIV disease progression. Among the relevant effects of DMF and its active metabolite monomethyl fumarate (MMF) are induction of a Th1 → Th2 lymphocyte shift, inhibition of pro-inflammatory cytokine signaling, inhibition of NF-κB nuclear translocation, inhibition of dendritic cell maturation, suppression of lymphocyte and endothelial cell adhesion molecule expression, and induction of the Nrf2-dependent antioxidant response element (ARE) and effector genes. Associated with these effects are reduced lymphocyte and monocyte infiltration into psoriatic skin lesions in humans and immune-mediated demyelinating brain lesions in rodents, which confirms potent systemic and central nervous system (CNS) effects. In addition, DMF and MMF limit HIV infection in macrophages in vitro, albeit by unknown mechanisms. Finally, DMF and MMF also suppress neurotoxin production from HIV-infected macrophages, which drives CNS neurodegeneration. Thus, DMF might protect against systemic and CNS complications in HIV infection through its effective suppression of immune activation, oxidative stress, HIV replication, and macrophage-associated neuronal injury. PMID:23971529

  17. ANTIOXIDANT SUPPLEMENTATION AND NASAL INFLAMMATORY RESPONSES AMONG YOUNG ASTHMATICS EXPOSED TO HIGH LEVELS OF OZONE

    EPA Science Inventory

    Background: Recent studies examining the inflammatory response in atopic asthma to ozone suggest a release of soluble mediators of inflammation factors that might be related to reactive oxygen species (ROS). Antioxidant could prove useful in subjects exposed to additional oxidati...

  18. Influence of diet, vitamin, tea, trace elements and exogenous antioxidants on arsenic metabolism and toxicity.

    PubMed

    Yu, Haiyan; Liu, Su; Li, Mei; Wu, Bing

    2016-04-01

    Health risk of arsenic (As) has received increasing attention. Acute and chronic exposure to As could cause several detrimental effects on human health. As toxicity is closely related to its bioaccessibility and metabolism. In real environment, many factors, such as diet and nutrition, can influence As bioaccessibility, metabolism and toxicity. This paper mainly reviews the influences of diets and elements on As bioaccessibility, metabolism and toxicity and their underlying mechanisms to provide suggestions for future investigations. Vitamins, jaggery, fruit, tea, glutathione, N-acetylcysteine and zinc could reduce the As-induced toxicity by increasing antioxidative enzymes to antagonize oxidative stress caused by As and/or increasing As methylation. However, bean and betel nut could increase risk of skin lesions caused by As. Interestingly, high-fat diet, selenium and iron have incompatible effects on As bioaccessibility, metabolism and toxicity in different experimental conditions. Based on current literatures, the As methylation and As-induced oxidative damage might be two main ways that the diets and elements influence As toxicity. Combined application of in vitro human cell lines and gastrointestinal models might be useful tools to simultaneously characterize the changes in As bioaccessibility and toxicity in the future research.

  19. Ablative Thermal Response Analysis Using the Finite Element Method

    NASA Technical Reports Server (NTRS)

    Dec John A.; Braun, Robert D.

    2009-01-01

    A review of the classic techniques used to solve ablative thermal response problems is presented. The advantages and disadvantages of both the finite element and finite difference methods are described. As a first step in developing a three dimensional finite element based ablative thermal response capability, a one dimensional computer tool has been developed. The finite element method is used to discretize the governing differential equations and Galerkin's method of weighted residuals is used to derive the element equations. A code to code comparison between the current 1-D tool and the 1-D Fully Implicit Ablation and Thermal Response Program (FIAT) has been performed.

  20. Analysis of Indian mint (Mentha spicata) for essential, trace and toxic elements and its antioxidant behaviour.

    PubMed

    Choudhury, R Paul; Kumar, A; Garg, A N

    2006-06-01

    Mint, belonging to the genus Mentha in the family Labiatae (Lamiaceae) is pungent in taste with post digestive effects and hot potency. Ten samples of mint leaves, collected from four different locations in North-West parts of India (Roorkee, Dehradun, Baghpat and Uttarkashi) were analysed for seven minor (Al, Na, K, Ca, Cl, Mg, and P) and 20 trace (As, Au, Ba, Br, Co, Cr, Cs, Eu, Fe, Hf, Hg, La, Mn, Rb, Sb, Sc, Se, Sn, Th and Zn) elements by instrumental neutron activation analysis (INAA). Also Ni, Cu and Cd were determined by atomic absorption spectrophotometry (AAS). Samples along with reference materials (RMs) and synthetic primary standard were irradiated at approximately 10(13) n cm-2s-1 and its gamma-activity was measured using HPGe detector and MCA system. Most elements were found in widely varying amounts depending on the location, e.g. Na (0.21-0.86 mg/g), K (12.4-53.3 mg/g) and Ca (5.82-16.8 mg/g) whereas mean contents of other nutrient elements in mint were: Fe (108+/-22 microg/g), Mg (4.83+/-0.92 mg/g), Mn (53.5+/-9.6 microg/g), P (3.88+/-0.94 mg/g), Cu (16.9+/-1.8 microg/g), Zn (21.0+/-4.7 microg/g) and Se (0.18+/-0.03 microg/g). Further, DPPH free radical scavenging activity test in diethyl ether extract showed 100% activity at approximately 40 microg/L suggesting it to be antioxidant in accordance with literature reports.

  1. Optimization of ultrasonic extraction of phenolic antioxidants from green tea using response surface methodology.

    PubMed

    Lee, Lan-Sook; Lee, Namhyouck; Kim, Young Ho; Lee, Chang-Ho; Hong, Sang Pil; Jeon, Yeo-Won; Kim, Young-Eon

    2013-10-31

    Response surface methodology (RSM) has been used to optimize the extraction conditions of antioxidants with relatively low caffeine content from green tea by using ultrasonic extraction. The predicted optimal conditions for the highest antioxidant activity and minimum caffeine level were found at 19.7% ethanol, 26.4 min extraction time, and 24.0 ° C extraction temperature. In the predicted optimal conditions, the experimental values were very close to the predicted values. Moreover, the ratio of (EGCg + ECg)/EGC was identified a major factor contributing to the antioxidant activity of green tea extracts. In this study, ultrasonic extraction showed that the ethanol concentration and extraction time used for antioxidant extraction could be remarkably reduced without a decrease in antioxidant activity compared to the conventional extraction conditions.

  2. Nitrate, ascorbic acid, mineral and antioxidant activities of Cosmos caudatus in response to organic and mineral-based fertilizer rates.

    PubMed

    Hassan, Siti Aishah; Mijin, Salumiah; Yusoff, Umi Kalsom; Ding, Phebe; Wahab, Puteri Edaroyati Megat

    2012-06-28

    The source and quantity of nutrients available to plants can affect the quality of leafy herbs. A study was conducted to compare quality of Cosmos caudatus in response to rates of organic and mineral-based fertilizers. Organic based fertilizer GOBI (8% N:8% P₂O₅:8% K₂O) and inorganic fertilizer (15% N, 15% P₂O₅, 15% K₂O) were evaluated based on N element rates at 0, 30, 60, 90, 120 kg h⁻¹. Application of organic based fertilizer reduced nitrate, improved vitamin C, antioxidant activity as well as nitrogen and calcium nutrients content. Antioxidant activity and chlorophyll content were significantly higher with increased fertilizer application. Fertilization appeared to enhance vitamin C content, however for the maximum ascorbic acid content, regardless of fertilizer sources, plants did not require high amounts of fertilizer.

  3. Thresholds in shock response across the elements

    NASA Astrophysics Data System (ADS)

    Bourne, F. L.; Bourne, N. K.; CMEC Team

    2015-06-01

    Compendia of shock data have been assembled across national laboratories across the world. Previous work has shown a threshold in behaviour for materials; the weak shock limit. This corresponds the stress state at which the shock is overdriven in a single front. The shock velocity-particle velocity data for elements and compounds has been systematically analysed to note discontinuities in the data. A range of materials show these features and the form of the discontinuity in each case is analysed. Some correspond to martensitic phase transformations as expected whilst others are more difficult to track down. Particular groups within the elements show characteristic forms according to groupings in the periodic table. The datasets are presented and trends are noted.

  4. Hepatic positive and negative antioxidant responses in zebrafish after intraperitoneal administration of toxic microcystin-LR.

    PubMed

    Hou, Jie; Li, Li; Xue, Ting; Long, Meng; Su, Yujing; Wu, Ning

    2015-02-01

    Microcystin-LR (MC-LR) is the most toxic and common among microcystins. In order to understand the possible molecular mechanisms of hepatic antioxidation and detoxification, the activities and transcriptional levels of antioxidant enzymes including catalase (CAT), superoxide dismutase (SOD), glutathione peroxidase (GPx) and glutathione S-transferases (GST), and glutathione (GSH) contents as well as histopathological changes were studied in the liver of female zebrafish injected intraperitoneally (i.p.) at doses of 50 and 200 μg MC-LR kg(-1) body weight (BW) respectively. In the low dose group (50 μg MC-LR kg(-1)), zebrafish displayed a little unease at the initial 1h post-injection (hpi), slight hepatic injury and quick recovery, and enhanced enzymatic activities and up-regulated gene expression of antioxidant enzymes. In contrast, high dose of MC-LR (200 μg MC-LR kg(-1)) resulted in uneasiness and frantic swimming, severe hepatic injury, and suppressed enzymatic activities and down-regulated gene expression of antioxidant enzymes. GSH depletion in both dose groups may be explained by enhanced antioxidant reactions and higher rates of MC conjugation, suggesting the crucial roles of GSH in both cellular antioxidant protection and MC-LR detoxification. This study demonstrated that administration of MC-LR caused a positive response in the low dose group but a negative response in the high dose group. Hepatic positive/negative responses in the low/high dose group might result from an increased/decreased synthesis of antioxidant enzymes at the molecular level, respectively. These results illustrated that antioxidant status played an important role in zebrafish protection against MC-LR-caused oxidative stress through regulating antioxidant enzyme gene expression and activities. PMID:25462319

  5. Redox status and antioxidant response in professional cyclists during training.

    PubMed

    Leonardo-Mendonça, Roberto Carlos; Concepción-Huertas, Melquiades; Guerra-Hernández, Eduardo; Zabala, Mikel; Escames, Germaine; Acuña-Castroviejo, Darío

    2014-01-01

    The aim of this study was to investigate whether different phases of training affect oxidative stress and antioxidant defences in professional cyclists. Ten professional cyclists, aged 21.8 ± 2.5 years, were enrolled in the study. They were classified into two groups of five athletes each one with similar nutritional intake excepting for the overload of vitamin C (1000 mg day(-1)) and E (400 mg day(-1)) supplementation in one of them. The cyclists of both groups performed the same exercise design, consisting of hard, tapering and recovery training periods. Total antioxidant capacity (TAC) of the diet, plasma oxygen radical absorption capacity (ORAC), lipid peroxidation (LPO), DNA damage (8-OHdG) and erythrocyte glutathione disulfide/glutathione ratio (GSSG:GSH(-1)) were measured. During the intense exercise trainings, the cyclists without vitamin supplements had the TAC of diet significantly lower than the supplemented group. Plasma ORAC, LPO and 8-OHdG were similar in both groups of athletes. Athletes with supplements had a basal LPO:ORAC(-1) ratio lower than that without supplements, but this ratio converged to the same level at the end of the training in both groups of cyclists. Both groups of cyclists showed similar changes in GSSG:GSH(-1) ratio and in GSSG and GSH levels along the study. The data suggest that well-trained athletes with suitable ultra-endurance training volume and intensity do not require antioxidant vitamin supplements to adapt their endogenous antioxidant defenses to exercise-induced ROS.

  6. Responses of foliar antioxidative and photoprotective defence systems of trees to drought: a meta-analysis.

    PubMed

    Wujeska, Agnieszka; Bossinger, Gerd; Tausz, Michael

    2013-10-01

    Current climate change predictions hint to more frequent extreme weather events, including extended droughts, making better understanding of the impacts of water stress on trees even more important. At the individual plant level, stomatal closure as a result of water deficit leads to reduced CO2 availability in the leaf, which can lead to photo-oxidative stress. Photorespiration and the Mehler reaction can maintain electron transport rates under low internal CO2, but result in production of reactive oxygen species (ROS). If electron consumption is decreased, upstream photochemical processes can be affected and light energy is absorbed in excess of photochemical requirements. Trees evolved to cope with excess energy and elevated concentration of ROS by activating photoprotective and antioxidative defence systems. The meta-analysis we present here assessed responses of these defence systems reported in 50 studies. We found responses to vary depending on stress intensity, foliage type and habitat, and on whether experiments were done in the field or in controlled environments. In general, drought increased concentrations of antioxidants and photoprotective pigments. However, severe stress caused degradation of antioxidant concentrations and oxidation of antioxidant pools. Evergreen trees seemed to preferentially reinforce membrane-bound protection systems zeaxanthin and tocopherol, whereas deciduous species showed greater responses in water-soluble antioxidants ascorbic acid and glutathione. Trees and shrubs from arid versus humid habitats vary in their antioxidative and photoprotective defence responses. In field experiments, drought had greater effects on some defence compounds than under controlled conditions.

  7. Comparative antioxidant responses in liver of Carassius auratus exposed to phthalates: an integrated biomarker approach.

    PubMed

    Zheng, Qing; Feng, Mingbao; Dai, Yong

    2013-11-01

    Phthalates (PAEs) are chemical agents typically used as plasticizers in numerous industrial products. They have become ubiquitous contaminants due to their tendency to release into the environment. The present study was conducted to investigate the comparative antioxidant responses in liver of freshwater goldfish Carassius auratus injected intraperitoneally with 17 different PAEs at a concentration of 10 mg/kg for 10 days. The results indicated that these PAEs can adversely affect the antioxidant status, confirmed by the significantly inhibited activities of antioxidant enzymes (superoxide dismutase, catalase, and glutathione peroxidase). Especially, the latter two enzymes constituted the most affected antioxidant enzymes after the exposure, and the lowest values were recorded for the catalase activity. The toxicity order was proposed via the integrated biomarker response, with dicyclohexyl phthalate the most toxic and diethyl phthalate the least. Overall, these findings may contribute to the risk assessments of these chemicals on aquatic species.

  8. Antioxidant system responses in two co-occurring green-tide algae under stress conditions

    NASA Astrophysics Data System (ADS)

    Wang, Ying; Zhao, Xinyu; Tang, Xuexi

    2016-01-01

    Green tides have occurred every year from 2007 to 2014 in the Yellow Sea. Ulva prolifera (Müller) J. Agardh has been identified as the bloom-forming alga, co-occurring with U. intestinalis. We observed distinct strategies for both algal species during green tides. U. prolifera exhibited a high abundance initially and then decreased dramatically, while U. intestinalis persisted throughout. The antioxidant system responses of these two macroalgae were compared in the late phase of a green tide (in-situ) and after laboratory acclimation. Lipid peroxidation and antioxidant system responses differed significantly between the two. Malondialdehyde and hydrogen peroxide contents increased significantly in-situ in U. prolifera, but not in U. intestinalis. In U. prolifera, we observed a significant decrease in total antioxidant ability (T-AOC), antioxidant enzymes (SOD and Apx), and non-enzyme antioxidants (GSH and AsA) in-situ. U. intestinalis showed the same pattern of T-AOC and SOD, but its Gpx, Apx, and GSH responses did not differ significantly. The results suggest that U. prolifera was more susceptible than U. intestinalis to the harsh environmental changes during the late phase of a Yellow Sea green tide. The boom and bust strategy exhibited by U. prolifera and the persistence of U. intestinalis can be explained by differences in enzyme activity and antioxidant systems.

  9. Prediction of nuclear hormone receptor response elements.

    PubMed

    Sandelin, Albin; Wasserman, Wyeth W

    2005-03-01

    The nuclear receptor (NR) class of transcription factors controls critical regulatory events in key developmental processes, homeostasis maintenance, and medically important diseases and conditions. Identification of the members of a regulon controlled by a NR could provide an accelerated understanding of development and disease. New bioinformatics methods for the analysis of regulatory sequences are required to address the complex properties associated with known regulatory elements targeted by the receptors because the standard methods for binding site prediction fail to reflect the diverse target site configurations. We have constructed a flexible Hidden Markov Model framework capable of predicting NHR binding sites. The model allows for variable spacing and orientation of half-sites. In a genome-scale analysis enabled by the model, we show that NRs in Fugu rubripes have a significant cross-regulatory potential. The model is implemented in a web interface, freely available for academic researchers, available at http://mordor.cgb.ki.se/NHR-scan.

  10. Substoichiometric hydroxynonenylation of a single protein recapitulates whole-cell-stimulated antioxidant response.

    PubMed

    Parvez, Saba; Fu, Yuan; Li, Jiayang; Long, Marcus J C; Lin, Hong-Yu; Lee, Dustin K; Hu, Gene S; Aye, Yimon

    2015-01-14

    Lipid-derived electrophiles (LDEs) that can directly modify proteins have emerged as important small-molecule cues in cellular decision-making. However, because these diffusible LDEs can modify many targets [e.g., >700 cysteines are modified by the well-known LDE 4-hydroxynonenal (HNE)], establishing the functional consequences of LDE modification on individual targets remains devilishly difficult. Whether LDE modifications on a single protein are biologically sufficient to activate discrete redox signaling response downstream also remains untested. Herein, using T-REX (targetable reactive electrophiles and oxidants), an approach aimed at selectively flipping a single redox switch in cells at a precise time, we show that a modest level (∼34%) of HNEylation on a single target is sufficient to elicit the pharmaceutically important antioxidant response element (ARE) activation, and the resultant strength of ARE induction recapitulates that observed from whole-cell electrophilic perturbation. These data provide the first evidence that single-target LDE modifications are important individual events in mammalian physiology.

  11. Finite Element Modeling of the Buckling Response of Sandwich Panels

    NASA Technical Reports Server (NTRS)

    Rose, Cheryl A.; Moore, David F.; Knight, Norman F., Jr.; Rankin, Charles C.

    2002-01-01

    A comparative study of different modeling approaches for predicting sandwich panel buckling response is described. The study considers sandwich panels with anisotropic face sheets and a very thick core. Results from conventional analytical solutions for sandwich panel overall buckling and face-sheet-wrinkling type modes are compared with solutions obtained using different finite element modeling approaches. Finite element solutions are obtained using layered shell element models, with and without transverse shear flexibility, layered shell/solid element models, with shell elements for the face sheets and solid elements for the core, and sandwich models using a recently developed specialty sandwich element. Convergence characteristics of the shell/solid and sandwich element modeling approaches with respect to in-plane and through-the-thickness discretization, are demonstrated. Results of the study indicate that the specialty sandwich element provides an accurate and effective modeling approach for predicting both overall and localized sandwich panel buckling response. Furthermore, results indicate that anisotropy of the face sheets, along with the ratio of principle elastic moduli, affect the buckling response and these effects may not be represented accurately by analytical solutions. Modeling recommendations are also provided.

  12. Tolerance and antioxidant response of a dark septate endophyte (DSE), Exophiala pisciphila, to cadmium stress.

    PubMed

    Zhan, Fangdong; He, Yongmei; Li, Tao; Yang, Yun-ya; Toor, Gurpal S; Zhao, Zhiwei

    2015-01-01

    The growth, oxidative damage and antioxidant response of Exophiala pisciphila ACCC32496, a dark septate endophyte isolated from an abandoned lead-zinc mining area, were measured at cadmium (Cd) concentrations of 0, 25, 50, 100, 200 and 400 mg L(-1). The EC50 values of E. pisciphila ACCC32496 to Cd were 332.2 mg L(-1) after 30 days on solid medium and 111.2 mg L(-1) after 7 days in liquid medium. Cd stress markedly stimulated the production of superoxide anion, H2O2 and malondialdehyde in the fungal mycelia. The activities of superoxide dismutase and catalase reached their maxima at 100 mg L(-1) Cd. The glutathione and non-protein thiol contents, along with the total antioxidant capability, reached their maxima at 50 mg L(-1) Cd. Low Cd concentrations induced a noticeable increase in antioxidant defense, while high Cd concentrations decreased the antioxidant defense. PMID:25323040

  13. Yields, phenolic profiles and antioxidant activities of Ziziphus jujube Mill. in response to different fertilization treatments.

    PubMed

    Wu, Chun-Sen; Gao, Qing-Han; Kjelgren, Roger Keith; Guo, Xu-Dan; Wang, Min

    2013-01-01

    Increasing demand for more jujube (Ziziphus jujube Mill.) production requires understanding the specific fertilization needs of jujube trees. This study was conducted to compare fruit yields, phenolic profiles and antioxidant activity of jujube in response to different fertilizers. Application of organic fertilizer appeared to enhance the phenolics and antioxidant activity accumulation of jujubes, compared to conventional fertilized jujubes. Amongst inorganic fertilizers, supplemental potassium as an individual nutrient improved the accumulation of phenolics in jujubes. Our results demonstrate that phenolics levels and antioxidant activity of jujube can be manipulated through fertilizer management and tracked by following proanthocyanidin concentrations. In a practical production context, the combination of organic fertilizers and inorganic fertilizers such as more supplemental individual potassium, and less supplemental individual nitrogen and phosphorus, might be the best management combination for achieving higher phenolic concentration, stronger antioxidant activity and a good harvest. PMID:24084012

  14. Transposable elements in response to environmental stressors&

    PubMed Central

    Miousse, Isabelle R.; Chalbot, Marie-Cecile G.; Lumen, Annie; Ferguson, Alesia; Kavouras, Ilias G.; Koturbash, Igor

    2015-01-01

    Transposable elements (TEs) comprise a group of repetitive sequences that bring positive, negative, as well as neutral effects to the host organism. Earlier considered as “junk DNA,” TEs are now well-accepted driving forces of evolution and critical regulators the of expression of genetic information. Their activity is regulated by epigenetic mechanisms, including methylation of DNA and histone modifications. The loss of epigenetic control over TEs, exhibited as loss of DNA methylation and decondensation of the chromatin structure, may result in TEs reactivation, initiation of their insertional mutagenesis (retrotransposition) and has been reported in numerous human diseases, including cancer. Accumulating evidence suggests that these alterations are not the simple consequences of the disease, but often may drive the pathogenesis, as they can be detected early during disease development. Knowledge derived from the in vitro, in vivo, and epidemiological studies, clearly demonstrates that exposure to ubiquitous environmental stressors, many of which are carcinogens or suspected carcinogens, are capable of causing alterations in methylation and expression of TEs and initiate retrotransposition events. Evidence summarized in this review suggests that TEs are the sensitive endpoints for detection of effects caused by such environmental stressors, as ionizing radiation (terrestrial, space, and UV-radiation), air pollution (including particulate matter [PM]-derived and gaseous), persistent organic pollutants, and metals. Furthermore, the significance of these effects is characterized by their early appearance, persistence and presence in both, target organs and peripheral blood. Altogether, these findings suggest that TEs may potentially be introduced into safety and risk assessment and serve as biomarkers of exposure to environmental stressors. Furthermore, TEs also show significant potential to become invaluable surrogate biomarkers in clinic and possible targets

  15. Response of transposable elements to environmental stressors.

    PubMed

    Miousse, Isabelle R; Chalbot, Marie-Cecile G; Lumen, Annie; Ferguson, Alesia; Kavouras, Ilias G; Koturbash, Igor

    2015-01-01

    Transposable elements (TEs) comprise a group of repetitive sequences that bring positive, negative, as well as neutral effects to the host organism. Earlier considered as "junk DNA," TEs are now well-accepted driving forces of evolution and critical regulators of the expression of genetic information. Their activity is regulated by epigenetic mechanisms, including methylation of DNA and histone modifications. The loss of epigenetic control over TEs, exhibited as loss of DNA methylation and decondensation of the chromatin structure, may result in TEs reactivation, initiation of their insertional mutagenesis (retrotransposition) and has been reported in numerous human diseases, including cancer. Accumulating evidence suggests that these alterations are not the simple consequences of the disease, but often may drive the pathogenesis, as they can be detected early during disease development. Knowledge derived from the in vitro, in vivo, and epidemiological studies, clearly demonstrates that exposure to ubiquitous environmental stressors, many of which are carcinogens or suspected carcinogens, are capable of causing alterations in methylation and expression of TEs and initiate retrotransposition events. Evidence summarized in this review suggests that TEs are the sensitive endpoints for detection of effects caused by such environmental stressors, as ionizing radiation (terrestrial, space, and UV-radiation), air pollution (including particulate matter [PM]-derived and gaseous), persistent organic pollutants, and metals. Furthermore, the significance of these effects is characterized by their early appearance, persistence and presence in both, target organs and peripheral blood. Altogether, these findings suggest that TEs may potentially be introduced into safety and risk assessment and serve as biomarkers of exposure to environmental stressors. Furthermore, TEs also show significant potential to become invaluable surrogate biomarkers in clinic and possible targets for

  16. Studies on the effects on growth and antioxidant responses of two marine microalgal species to uniconazole

    NASA Astrophysics Data System (ADS)

    Mei, Xueqiao; Zheng, Kang; Wang, Lingdong; Li, Yantuan

    2014-10-01

    Uniconazole, as a plant growth retardant, can enhance stress tolerance in plants, possibly because of improved antioxidation defense mechanisms with higher activities of superoxide dismutase (SOD) and peroxidase (POD) enzymes that retard lipid peroxidation and membrane deterioration. These years much attention has been focused on the responses of antioxidant system in plants to uniconazole stress, but such studies on aquatic organism are very few. Moreover, no information is available on growth and antioxidant response in marine microalgae to uniconazole. In this paper, the growth and antioxidant responses of two marine microalgal species, Platymonas helgolandica and Pavlova viridis, at six uniconazole concentrations (0-15 mg L-1) were investigated. The results demonstrated that 3 mg L-1 uniconazole could increase significantly chlorophyll a and carbohydrate contents of P. helgolandica ( P < 0.05). Higher concentrations (≥12 mg L-1) of uniconazole could inhibit significantly the growth, dry weight, chlorophyll-a and carbohydrate contents of P. helgolandica and P. viridis ( P < 0.05). Uniconazole caused a significant increase in lipid peroxidation production (MDA) at higher concentrations (≥ 9 mg L-1). The activities of antioxidant enzymes, superoxide dismutase (SOD) and catalase (CAT) were enhanced remarkably at low concentrations of uniconazole. However, significant reduction of SOD and CAT activities was observed at higher concentrations of uniconazole.

  17. Evidence for Oxidative Stress and Defective Antioxidant Response in Guinea Pigs with Tuberculosis

    PubMed Central

    Palanisamy, Gopinath S.; Kirk, Natalie M.; Ackart, David F.; Shanley, Crystal A.; Orme, Ian M.; Basaraba, Randall J.

    2011-01-01

    The development of granulomatous inflammation with caseous necrosis is an important but poorly understood manifestation of tuberculosis in humans and some animal models. In this study we measured the byproducts of oxidative stress in granulomatous lesions as well as the systemic antioxidant capacity of BCG vaccinated and non-vaccinated guinea pigs experimentally infected with Mycobacterium tuberculosis. In non-vaccinated guinea pigs, oxidative stress was evident within 2 weeks of infection as measured by a decrease in the serum total antioxidant capacity and blood glutathione levels accompanied by an increase in malondialdehyde, a byproduct of lipid peroxidation, within lesions. Despite a decrease in total and reduced blood glutathione concentrations, there was an increase in lesion glutathione by immunohistochemistry in response to localized oxidative stress. In addition there was an increase in the expression of the host transcription factor nuclear erythroid 2 p45-related factor 2 (Nrf2), which regulates several protein and non-proteins antioxidants, including glutathione. Despite the increase in cytoplasmic expression of Nrf2, immunohistochemical staining revealed a defect in Nrf2 nuclear translocation within granulomatous lesions as well as a decrease in the expression of the Nrf2-regulated antioxidant protein NQO1. Treating M. tuberculosis–infected guinea pigs with the antioxidant drug N-acetyl cysteine (NAC) partially restored blood glutathione concentrations and the serum total antioxidant capacity. Treatment with NAC also decreased spleen bacterial counts, as well as decreased the lung and spleen lesion burden and the severity of lesion necrosis. These data suggest that the progressive oxidative stress during experimental tuberculosis in guinea pigs is due in part to a defect in host antioxidant defenses, which, we show here, can be partially restored with antioxidant treatment. These data suggest that the therapeutic strategies that reduce oxidant

  18. Polymer Directed Self-Assembly of pH-Responsive Antioxidant Nanoparticles

    PubMed Central

    Tang, Christina; Amin, Devang; Messersmith, Phillip B.; Anthony, John E.; Prud’homme, Robert K.

    2015-01-01

    We have developed pH-responsive, multifunctional nanoparticles based on encapsulation of an antioxidant, tannic acid (TA), using Flash NanoPrecipitation, a polymer directed self-assembly method. Formation of insoluble coordination complexes of tannic acid and iron during mixing drives nanoparticle assembly. Tuning the core material to polymer ratio, the size of the nanoparticles can be readily tuned between 50 and 265 nm. The resulting nanoparticle is pH-responsive, i.e. stable at pH 7.4 and soluble under acidic conditions due to the nature of the coordination complex. Further, the coordination complex can be coprecipitated with other hydrophobic materials such as therapeutics or imaging agents. For example, coprecipitation with a hydrophobic fluorescent dye creates fluorescent nanoparticles. In vitro, the nanoparticles have low cytotoxicity show antioxidant activity. Therefore, these particles may facilitate intracellular delivery of antioxidants. PMID:25760226

  19. Polymer directed self-assembly of pH-responsive antioxidant nanoparticles.

    PubMed

    Tang, Christina; Amin, Devang; Messersmith, Phillip B; Anthony, John E; Prud'homme, Robert K

    2015-03-31

    We have developed pH-responsive, multifunctional nanoparticles based on encapsulation of an antioxidant, tannic acid (TA), using flash nanoprecipitation, a polymer directed self-assembly method. Formation of insoluble coordination complexes of tannic acid and iron during mixing drives nanoparticle assembly. Tuning the core material to polymer ratio, the size of the nanoparticles can be readily tuned between 50 and 265 nm. The resulting nanoparticle is pH-responsive, i.e., stable at pH 7.4 and soluble under acidic conditions due to the nature of the coordination complex. Further, the coordination complex can be coprecipitated with other hydrophobic materials such as therapeutics or imaging agents. For example, coprecipitation with a hydrophobic fluorescent dye creates fluorescent nanoparticles. In vitro, the nanoparticles have low cytotoxicity and show antioxidant activity. Therefore, these particles may facilitate intracellular delivery of antioxidants. PMID:25760226

  20. The growth, photosynthesis and antioxidant defense responses of five vegetable crops to phenanthrene stress.

    PubMed

    Ahammed, Golam Jalal; Wang, Meng-Meng; Zhou, Yan-Hong; Xia, Xiao-Jian; Mao, Wei-Hua; Shi, Kai; Yu, Jing-Quan

    2012-06-01

    Polycyclic aromatic hydrocarbons (PAHs) are global environmental problem. To better understand the growth and physiological responses to atmospheric PAHs, we investigated biomass, photosynthetic machinery and antioxidant system in pakchoi, cucumber, flowering chinese cabbage, tomato and lettuce under various levels of phenanthrene (PHE) stress. Foliar exposure to PHE for 14d resulted in a dose dependent decrease in growth, photosynthesis and chlorophyll contents. With few exceptions, antioxidant enzymes (superoxide dismutase, guaicol peroxidase, catalase, ascorbate peroxidase and glutathione reductase) were upregulated following exposure to PHE. Dose dependent increase in malondialdehyde contents together with H(2)O(2) accumulation suggested an occurrence of oxidative stress following PHE exposure. However, to some extent, growth and antioxidant defense responses differ from species to species. Difference in defense capacity might result in different tolerance and phytotoxicity among the studied vegetables. Taken together, phytotoxicity of PHE to five vegetables could be sequenced in the following order: pakchoi>cucumber>lettuce>tomato>flowering chinese cabbage.

  1. Antioxidant response and related gene expression in aged oat seed

    PubMed Central

    Kong, Lingqi; Huo, Heqiang; Mao, Peisheng

    2015-01-01

    To evaluate deterioration of oat seeds during storage, we analyzed oxygen radicals, antioxidant enzyme activity, proline content, and gene transcript levels in oat seeds with different moisture contents (MCs; 4, 16, and 28% w/w) during storage for 0, 6, and 12 months (CK, LT-6, and LT-12 treatments, respectively) at 4°C. The germination percentage decreased significantly with higher seed MCs and longer storage duration. The concentrations of superoxide radical and hydrogen peroxide increased with seed MC increasing. The activities of catalase (CAT), ascorbate peroxidase (APX), and superoxide dismutase (SOD) may have had a complementary or interacting role to scavenge reactive oxygen species. As the storage duration extended, the proline content decreased in seeds with 4 and 16% MC and increased in 28%. These findings suggest that proline played the main role in adaptation to oxidative stress in seeds with higher MC (28%), while antioxidant enzymes played the main role in seeds with lower MCs (4%, 16%). In the gene transcript analyses, SOD1 transcript levels were not consistent with total SOD activity. The transcript levels of APX1 and CAT1 showed similar trends to those of APX and CAT activity. The transcript levels of P5CS1, which encodes a proline biosynthetic enzyme, increased with seed MC increasing in CK. Compared with changing of proline content in seeds stored 12 months, PDH1 transcript levels showed the opposite trend and maintained the lower levels in seeds of 16 and 28% MCs. The transcript level of P5CS1 was significantly affected by MC, and PDH1 could improve stress resistance for seed aging and maintain seed vigor during long-term storage. PMID:25852711

  2. Inflammation-responsive antioxidant nanoparticles based on a polymeric prodrug of vanillin.

    PubMed

    Kwon, Jeongil; Kim, Jihye; Park, Seunggyu; Khang, Gilson; Kang, Peter M; Lee, Dongwon

    2013-05-13

    Oxidative stress is induced by accumulation of hydrogen peroxide (H2O2), and therefore, H2O2 could serve as a potential biomarker of various oxidative stress-associated inflammatory diseases. Vanillin is one of the major components of natural vanilla and has potent antioxidant and anti-inflammatory activities. In this work, we developed a novel inflammation-responsive antioxidant polymeric prodrug of vanillin, termed poly(vanillin oxalate) (PVO). In design, PVO incorporates H2O2-reacting peroxalate ester bonds and bioactive vanillin via acid-responsive acetal linkages in its backbone. Therefore, in cells undergoing damages by oxidative stress, PVO readily degrades into three nontoxic components, one of which is antioxidant and anti-inflammatory vanillin. PVO nanoparticles exhibit potent antioxidant activities by scavenging H2O2 and inhibiting the generation of ROS (reactive oxygen species) and also reduce the expression of pro-inflammatory cytokines in activated macrophages in vitro and in vivo. We, therefore, anticipate that PVO nanoparticles have great potential as novel antioxidant therapeutics and drug delivery systems for ROS-associated inflammatory diseases.

  3. Antioxidative responses and bioaccumulation in Japanese flounder larvae and juveniles under chronic mercury exposure.

    PubMed

    Huang, Wei; Cao, Liang; Ye, Zhenjiang; Yin, Xuebo; Dou, Shuozeng

    2010-06-01

    This study investigated the sub-lethal effects of waterborne mercury on growth, bioaccumulation and antioxidative responses of larvae and juveniles of Japanese flounder (Paralichthys olivaceus). Fish were exposed to 0-10 microg Hg(2)(+)L(-1) solutions from embryonic to the juvenile stages for 80 days. Antioxidative responses to mercury exposure were studied in metamorphosing larvae (18 days post hatching, dph), settling larvae (33 dph) and juveniles (78 dph). Results showed that increasing mercury concentration led to increased mercury bioaccumulation and reduced flounder growth. Of the antioxidants investigated, superoxide dismutase (SOD) and catalase (CAT) activities at the three developmental stages were sensitive to mercury exposure and increased with increasing mercury concentration. Glutathione (GSH) content was elevated in metamorphosing larvae, but decreased in juveniles as mercury concentration increased. Glutathione-S-transferase (GST) activity did not significantly vary with mercury concentration in either larvae or juveniles. Mercury exposure did not affect malondialdehyde (MDA) content of larvae, but significantly increased MDA content of juveniles. Results suggest that flounder larvae and juveniles have the potential to manipulate the levels of antioxidants such as SOD, CAT and GSH, which protect flounder from oxidative stress induced by mercury exposure. These antioxidants could serve as biomarkers of mercury contamination in the aquatic environment.

  4. Diffractive micro-optical element with nonpoint response

    NASA Astrophysics Data System (ADS)

    Soifer, Victor A.; Golub, Michael A.

    1993-01-01

    Common-use diffractive lenses have microrelief zones in the form of simple rings that provide only an optical power but do not contain any image information. They have a point-image response under point-source illumination. We must use a more complicated non-point response to focus a light beam into different light marks, letter-type images as well as for optical pattern recognition. The current presentation describes computer generation of diffractive micro- optical elements with complicated curvilinear zones of a regular piecewise-smooth structure and grey-level or staircase phase microrelief. The manufacture of non-point response elements uses the steps of phase-transfer calculation and orthogonal-scan masks generation or lithographic glass etching. Ray-tracing method is shown to be applicable in this task. Several working samples of focusing optical elements generated by computer and photolithography are presented. Using the experimental results we discuss here such applications as laser branding.

  5. S-allyl cysteine activates the Nrf2-dependent antioxidant response and protects neurons against ischemic injury in vitro and in vivo.

    PubMed

    Shi, Huanying; Jing, Xu; Wei, Xinbing; Perez, Ruth G; Ren, Manru; Zhang, Xiumei; Lou, Haiyan

    2015-04-01

    Stroke is a devastating clinical condition for which an effective neuroprotective treatment is currently unavailable. S-allyl cysteine (SAC), the most abundant organosulfur compound in aged garlic extract, has been reported to possess neuroprotective effects against stroke. However, the mechanisms underlying its beneficial effects remain poorly defined. The present study tests the hypothesis that SAC attenuates ischemic neuronal injury by activating the nuclear factor erythroid-2-related factor 2 (Nrf2)-dependent antioxidant response in both in vitro and in vivo models. Our findings demonstrate that SAC treatment resulted in an increase in Nrf2 protein levels and subsequent activation of antioxidant response element pathway genes in primary cultured neurons and mice. Exposure of primary neurons to SAC provided protection against oxygen and glucose deprivation-induced oxidative insults. In wild-type (Nrf2(+/+) ) mice, systemic administration of SAC attenuated middle cerebral artery occlusion-induced ischemic damage, a protective effect not observed in Nrf2 knockout (Nrf2(-/-) ) mice. Taken together, these findings provide the first evidence that activation of the Nrf2 antioxidant response by SAC is strongly associated with its neuroprotective effects against experimental stroke and suggest that targeting the Nrf2 pathway may provide therapeutic benefit for the treatment of stroke. The transcription factor Nrf2 is involved in cerebral ischemic disease and may be a promising target for the treatment of stroke. We provide novel evidence that SAC confers neuroprotection against ischemic stroke by activating the antioxidant Nrf2 signaling pathway. ARE, antioxidant response element; GCLC, glutathione cysteine ligase regulatory subunit; GCLM, glutathione cysteine ligase modulatory subunit; HO-1, heme oxygenase-1; JNK, c-Jun N-terminal kinase; Keap1, Kelch-like ECH-associated protein 1; Maf, musculoaponeurotic fibrosarcoma; Nrf2, nuclear factor erythroid-2-related factor 2

  6. S-allyl cysteine activates the Nrf2-dependent antioxidant response and protects neurons against ischemic injury in vitro and in vivo.

    PubMed

    Shi, Huanying; Jing, Xu; Wei, Xinbing; Perez, Ruth G; Ren, Manru; Zhang, Xiumei; Lou, Haiyan

    2015-04-01

    Stroke is a devastating clinical condition for which an effective neuroprotective treatment is currently unavailable. S-allyl cysteine (SAC), the most abundant organosulfur compound in aged garlic extract, has been reported to possess neuroprotective effects against stroke. However, the mechanisms underlying its beneficial effects remain poorly defined. The present study tests the hypothesis that SAC attenuates ischemic neuronal injury by activating the nuclear factor erythroid-2-related factor 2 (Nrf2)-dependent antioxidant response in both in vitro and in vivo models. Our findings demonstrate that SAC treatment resulted in an increase in Nrf2 protein levels and subsequent activation of antioxidant response element pathway genes in primary cultured neurons and mice. Exposure of primary neurons to SAC provided protection against oxygen and glucose deprivation-induced oxidative insults. In wild-type (Nrf2(+/+) ) mice, systemic administration of SAC attenuated middle cerebral artery occlusion-induced ischemic damage, a protective effect not observed in Nrf2 knockout (Nrf2(-/-) ) mice. Taken together, these findings provide the first evidence that activation of the Nrf2 antioxidant response by SAC is strongly associated with its neuroprotective effects against experimental stroke and suggest that targeting the Nrf2 pathway may provide therapeutic benefit for the treatment of stroke. The transcription factor Nrf2 is involved in cerebral ischemic disease and may be a promising target for the treatment of stroke. We provide novel evidence that SAC confers neuroprotection against ischemic stroke by activating the antioxidant Nrf2 signaling pathway. ARE, antioxidant response element; GCLC, glutathione cysteine ligase regulatory subunit; GCLM, glutathione cysteine ligase modulatory subunit; HO-1, heme oxygenase-1; JNK, c-Jun N-terminal kinase; Keap1, Kelch-like ECH-associated protein 1; Maf, musculoaponeurotic fibrosarcoma; Nrf2, nuclear factor erythroid-2-related factor 2

  7. Antioxidant responses to heat and light stress differ with habitat in a common reef coral

    NASA Astrophysics Data System (ADS)

    Hawkins, Thomas D.; Krueger, Thomas; Wilkinson, Shaun P.; Fisher, Paul L.; Davy, Simon K.

    2015-12-01

    Coral bleaching—the stress-induced collapse of the coral- Symbiodinium symbiosis—is a significant driver of worldwide coral reef degradation. Yet, not all corals are equally susceptible to bleaching, and we lack a clear understanding of the mechanisms underpinning their differential susceptibilities. Here, we focus on cellular redox regulation as a potential determinant of bleaching susceptibility in the reef coral Stylophora pistillata. Using slow heating (1 °C d-1) and altered irradiance, we induced bleaching in S. pistillata colonies sampled from two depths [5-8 m (shallow) and 15-18 m (deep)]. There was significant depth-dependent variability in the timing and extent of bleaching (loss of symbiont cells), as well as in host enzymatic antioxidant activity [specifically, superoxide dismutase and catalase (CAT)]. However, among the coral fragments that bleached, most did so without displaying any evidence of a host enzymatic antioxidant response. For example, both deep and shallow corals suffered significant symbiont loss at elevated temperature, but only deep colonies exposed to high temperature and high light displayed any up-regulation of host antioxidant enzyme activity (CAT). Surprisingly, this preceded the equivalent antioxidant responses of the symbiont, which raises questions about the source(s) of hydrogen peroxide in the symbiosis. Overall, changes in enzymatic antioxidant activity in the symbionts were driven primarily by irradiance rather than temperature, and responses were similar across depth groups. Taken together, our results suggest that in the absence of light stress, heating of 1 °C d-1 to 4 °C above ambient is not sufficient to induce a substantial oxidative challenge in S. pistillata. We provide some of the first evidence that regulation of coral enzymatic antioxidants can vary significantly depending on habitat, and, in terms of determining bleaching susceptibility, our results suggest a significant role for the host's differential

  8. Optimisation of antioxidant extraction from Solanum tuberosum potato peel waste by surface response methodology.

    PubMed

    Amado, Isabel Rodríguez; Franco, Daniel; Sánchez, Marivel; Zapata, Carlos; Vázquez, José Antonio

    2014-12-15

    This study reports the optimised conditions (temperature, ethanol concentration and processing-time) for antioxidant extraction from potato peel (Agria variety) waste. At short extraction times (34 min), optimal yields of phenolic (TP) and flavonoid (Fv) compounds were reached at 89.9°C and ethanol concentrations of 71.2% and 38.6%, respectively. The main phenolic compounds identified in the extracts were chlorogenic (Cl) and ferulic (Fer) acids. A significant positive correlation was found between antioxidant activity and TP, Fv, Fer and Cl responses. Potato peel extracts were able to stabilize soybean oil under accelerated oxidation conditions, minimising peroxide, totox and p-anisidine indices. The production of hexanal and 2-hexenal in soybean oil samples was maximal for extracts obtained at intermediate temperatures and ethanol concentrations. Our results demonstrate potato peel waste is a good source of antioxidants able to effectively limit oil oxidation, while contributing to the revalorisation of these agrifood by-products.

  9. Effect of antioxidant mineral elements supplementation in the treatment of hypertension in albino rats.

    PubMed

    Muhammad, S A; Bilbis, L S; Saidu, Y; Adamu, Y

    2012-01-01

    Oxidative stress has been implicated in various pathologies, including hypertension, atherosclerosis, diabetes, and chronic renal disease. The current work was designed with the aim of investigating the potentials of antioxidants copper, manganese, and zinc in the treatment of hypertension in Wistar rats. The rats were fed 8% NaCl diet for 5 weeks and treatment with supplements in the presence of the challenging agent for additional 4 weeks. The supplementation significantly decreased the blood pressure as compared with hypertensive control. The result also indicated significant decreased in the levels of total cholesterol, triglyceride, low-density lipoprotein cholesterol and very low-density lipoprotein cholesterol, malondialdehyde, insulin and increase in the high-density lipoprotein cholesterol, total antioxidant activities, and nitric oxide of the supplemented groups relative to the hypertensive control. The average percentage protection against atherogenesis indicated 47.13 ± 9.60% for all the supplemented groups. The mean arterial blood pressure showed significant positive correlation with glucose, total cholesterol, triglyceride, low-density lipoprotein cholesterol, very low-density lipoprotein cholesterol, atherogenic index, insulin resistance and malondialdehyde while high density lipoprotein-cholesterol and total antioxidant activities showed negative correlation. The result therefore indicated strong relationship between oxidative stress and hypertension and underscores the role of antioxidant minerals in reducing oxidative stress, dyslipidemia, and insulin resistance associated with hypertension. PMID:22966412

  10. Factors Affecting Antioxidant Response in Fish from a Long-term Mercury-Contaminated Reservoir.

    PubMed

    Sevcikova, M; Modra, H; Blahova, J; Dobsikova, R; Kalina, J; Zitka, O; Kizek, R; Svobodova, Z

    2015-11-01

    The objective of this work was to evaluate antioxidant defence and oxidative damage in organs (liver, gills, kidney, and brain) of five fish species (Aspius aspius, Esox lucius, Sander lucioperca, Abramis brama, Rutilus rutilus) from the long-term mercury-contaminated Skalka Reservoir in the Czech Republic. Special emphasis was placed on a comprehensive assessment of the factors that may affect the antioxidant response to mercury in fish. Antioxidant enzymes (glutathione reductase, glutathione peroxidase, and glutathione-S-transferase) did not significantly respond to mercury contamination. Levels of the analysed enzymes and oxidative damage to lipids were predominantly determined by a separate organ factor or species factor, or by the combination of both (p < 0.001). Levels of total glutathione and the reduced/oxidized glutathione ratio were influenced by mercury contamination in combination with their specific organ distribution (p < 0.001). Our results suggest that species and type of organ alone or in combination are more important factors than chronic exposure to mercury contamination with respect to effects on antioxidant defence in fish under field conditions. Our findings suggest that the main antioxidant defensive mechanism in fish from the studied long-term mercury contaminated site was the inter-tissue distribution of glutathione.

  11. Factors Affecting Antioxidant Response in Fish from a Long-term Mercury-Contaminated Reservoir.

    PubMed

    Sevcikova, M; Modra, H; Blahova, J; Dobsikova, R; Kalina, J; Zitka, O; Kizek, R; Svobodova, Z

    2015-11-01

    The objective of this work was to evaluate antioxidant defence and oxidative damage in organs (liver, gills, kidney, and brain) of five fish species (Aspius aspius, Esox lucius, Sander lucioperca, Abramis brama, Rutilus rutilus) from the long-term mercury-contaminated Skalka Reservoir in the Czech Republic. Special emphasis was placed on a comprehensive assessment of the factors that may affect the antioxidant response to mercury in fish. Antioxidant enzymes (glutathione reductase, glutathione peroxidase, and glutathione-S-transferase) did not significantly respond to mercury contamination. Levels of the analysed enzymes and oxidative damage to lipids were predominantly determined by a separate organ factor or species factor, or by the combination of both (p < 0.001). Levels of total glutathione and the reduced/oxidized glutathione ratio were influenced by mercury contamination in combination with their specific organ distribution (p < 0.001). Our results suggest that species and type of organ alone or in combination are more important factors than chronic exposure to mercury contamination with respect to effects on antioxidant defence in fish under field conditions. Our findings suggest that the main antioxidant defensive mechanism in fish from the studied long-term mercury contaminated site was the inter-tissue distribution of glutathione. PMID:26276034

  12. Optimization of ultrasonic-assisted extraction of natural antioxidants from rice bran using response surface methodology.

    PubMed

    Tabaraki, Reza; Nateghi, Ashraf

    2011-11-01

    Ultrasonic technology was applied for extraction of polyphenols and antioxidants from the rice bran using ethanol as a food grade solvent. Response surface methodology (RSM) was used to optimize experimental conditions for extraction of polyphenols and antioxidants. Three independent variables such as solvent percentage (%), temperature (°C) and time (min) were studied. Effect of ethanol concentration was found to be significant on all responses. Total phenolic content (TPC) varied from 2.37 to 6.35mg gallic acid equivalent/g of dry sample. Antioxidant activity of the extracts was determined by the ferric reducing antioxidant power (FRAP) assay and scavenging activity of 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical. FRAP and DPPH values varied from 31.74 to 57.23μmol Fe(2+)/g of dry sample and 16.88% to 55.61% inhibition, respectively. Extraction yields ranged from 11 to 20.2%. Optimal ultrasonic-assisted extraction (UAE) conditions were identified as 65-67% ethanol, 51-54°C, 40-45min. The experimental values agreed with those predicted by SRM models, thus indicating suitability of the model employed and the success of RSM in optimizing the extraction conditions.

  13. Biopersistence of PEGylated Carbon Nanotubes Promotes a Delayed Antioxidant Response after Infusion into the Rat Hippocampus

    PubMed Central

    Dal Bosco, Lidiane; Weber, Gisele E.; Parfitt, Gustavo M.; Cordeiro, Arthur P.; Sahoo, Sangram K.; Fantini, Cristiano; Klosterhoff, Marta C.; Romano, Luis Alberto; Furtado, Clascídia A.; Santos, Adelina P.; Monserrat, José M.; Barros, Daniela M.

    2015-01-01

    Carbon nanotubes are promising nanomaterials for the diagnosis and treatment of brain disorders. However, the ability of these nanomaterials to cross cell membranes and interact with neural cells brings the need for the assessment of their potential adverse effects on the nervous system. This study aimed to investigate the biopersistence of single-walled carbon nanotubes functionalized with polyethylene glycol (SWCNT-PEG) directly infused into the rat hippocampus. Contextual fear conditioning, Y-maze and open field tasks were performed to evaluate the effects of SWCNT-PEG on memory and locomotor activity. The effects of SWCNT-PEG on oxidative stress and morphology of the hippocampus were assessed 1 and 7 days after infusion of the dispersions at 0.5, 1.0 and 2.1 mg/mL. Raman analysis of the hippocampal homogenates indicates the biopersistence of SWCNT-PEG in the hippocampus 7 days post-injection. The infusion of the dispersions had no effect on the acquisition or persistence of the contextual fear memory; likewise, the spatial recognition memory and locomotor activity were not affected by SWCNT-PEG. Histological examination revealed no remarkable morphological alterations after nanomaterial exposure. One day after the infusion, SWCNT-PEG dispersions at 0.5 and 1.0 mg/mL were able to decrease total antioxidant capacity without modifying the levels of reactive oxygen species or lipid hydroperoxides in the hippocampus. Moreover, SWCNT-PEG dispersions at all concentrations induced antioxidant defenses and reduced reactive oxygen species production in the hippocampus at 7 days post-injection. In this work, we found a time-dependent change in antioxidant defenses after the exposure to SWCNT-PEG. We hypothesized that the persistence of the nanomaterial in the tissue can induce an antioxidant response that might have provided resistance to an initial insult. Such antioxidant delayed response may constitute an adaptive response to the biopersistence of SWCNT-PEG in the

  14. An antioxidant response is involved in resistance of Giardia duodenalis to albendazole

    PubMed Central

    Argüello-García, Raúl; Cruz-Soto, Maricela; González-Trejo, Rolando; Paz-Maldonado, Luz María T.; Bazán-Tejeda, M. Luisa; Mendoza-Hernández, Guillermo; Ortega-Pierres, Guadalupe

    2015-01-01

    Albendazole (ABZ) is a therapeutic benzimidazole used to treat giardiasis that targets β-tubulin. However, the molecular bases of ABZ resistance in Giardia duodenalis are not understood because β-tubulin in ABZ-resistant clones lacks mutations explaining drug resistance. In previous work we compared ABZ-resistant (1.35, 8, and 250 μM) and ABZ-susceptible clones by proteomic analysis and eight proteins involved in energy metabolism, cytoskeleton dynamics, and antioxidant response were found as differentially expressed among the clones. Since ABZ is converted into sulphoxide (ABZ-SO) and sulphone (ABZ-SOO) metabolites we measured the levels of these metabolites, the antioxidant enzymes and free thiols in the susceptible and resistant clones. Production of reactive oxygen species (ROS) and levels of ABZ-SO/ABZ-SOO induced by ABZ were determined by fluorescein diacetate-based fluorescence and liquid chromatography respectively. The mRNA and protein levels of antioxidant enzymes (NADH oxidase, peroxiredoxin 1a, superoxide dismutase and flavodiiron protein) in these clones were determined by RT-PCR and proteomic analysis. The intracellular sulfhydryl (R-SH) pool was quantified using dinitrobenzoic acid. The results showed that ABZ induced ROS accumulation in the ABZ-susceptible Giardia cultures but not in the resistant ones whilst the accumulation of ABZ-SO and ABZ-SOO was lower in all ABZ-resistant cultures. Consistent with these findings, all the antioxidant enzymes detected and analyzed were upregulated in ABZ-resistant clones. Likewise the R-SH pool increased concomitantly to the degree of ABZ-resistance. These results indicate an association between accumulation of ABZ metabolites and a pro-oxidant effect of ABZ in Giardia-susceptible clones. Furthermore the antioxidant response involving ROS-metabolizing enzymes and intracellular free thiols in ABZ-resistant parasites suggest that this response may contribute to overcome the pro-oxidant cytotoxicity of ABZ. PMID

  15. Biopersistence of PEGylated Carbon Nanotubes Promotes a Delayed Antioxidant Response after Infusion into the Rat Hippocampus.

    PubMed

    Dal Bosco, Lidiane; Weber, Gisele E; Parfitt, Gustavo M; Cordeiro, Arthur P; Sahoo, Sangram K; Fantini, Cristiano; Klosterhoff, Marta C; Romano, Luis Alberto; Furtado, Clascídia A; Santos, Adelina P; Monserrat, José M; Barros, Daniela M

    2015-01-01

    Carbon nanotubes are promising nanomaterials for the diagnosis and treatment of brain disorders. However, the ability of these nanomaterials to cross cell membranes and interact with neural cells brings the need for the assessment of their potential adverse effects on the nervous system. This study aimed to investigate the biopersistence of single-walled carbon nanotubes functionalized with polyethylene glycol (SWCNT-PEG) directly infused into the rat hippocampus. Contextual fear conditioning, Y-maze and open field tasks were performed to evaluate the effects of SWCNT-PEG on memory and locomotor activity. The effects of SWCNT-PEG on oxidative stress and morphology of the hippocampus were assessed 1 and 7 days after infusion of the dispersions at 0.5, 1.0 and 2.1 mg/mL. Raman analysis of the hippocampal homogenates indicates the biopersistence of SWCNT-PEG in the hippocampus 7 days post-injection. The infusion of the dispersions had no effect on the acquisition or persistence of the contextual fear memory; likewise, the spatial recognition memory and locomotor activity were not affected by SWCNT-PEG. Histological examination revealed no remarkable morphological alterations after nanomaterial exposure. One day after the infusion, SWCNT-PEG dispersions at 0.5 and 1.0 mg/mL were able to decrease total antioxidant capacity without modifying the levels of reactive oxygen species or lipid hydroperoxides in the hippocampus. Moreover, SWCNT-PEG dispersions at all concentrations induced antioxidant defenses and reduced reactive oxygen species production in the hippocampus at 7 days post-injection. In this work, we found a time-dependent change in antioxidant defenses after the exposure to SWCNT-PEG. We hypothesized that the persistence of the nanomaterial in the tissue can induce an antioxidant response that might have provided resistance to an initial insult. Such antioxidant delayed response may constitute an adaptive response to the biopersistence of SWCNT-PEG in the

  16. Antioxidant responses of Propylaea japonica (Coleoptera: Coccinellidae) exposed to high temperature stress.

    PubMed

    Zhang, Shize; Fu, Wenyan; Li, Ning; Zhang, Fan; Liu, Tong-Xian

    2015-02-01

    Temperature is one of the most important environmental factors, and is responsible for a variety of physiological stress responses in organisms. Induced thermal stress is associated with elevated reactive oxygen species (ROS) generation leading to oxidative damage. The ladybeetle, Propylaea japonica (Thunberg) (Coleoptera: Coccinellidae), is considered a successful natural enemy because of its tolerance to high temperatures in arid and semi-arid areas in China. In this study, we investigated the effect of high temperatures (35, 37, 39, 41 and 43 °C) on the survival and activities of antioxidant enzymes, including superoxide dismutase (SOD), catalase (CAT), peroxidases (POD), glutathione-S-transferases (GST), and total antioxidant capacity (TAC) as well as malondialdehyde (MDA) concentrations in P. japonica adults. The results indicated that P. japonica adults could not survive at 43 °C. CAT, GST and TAC were significantly increased when compared to the control (25 °C), and this played an important role in the process of antioxidant response to thermal stress. SOD and POD activity, as well as MDA, did not differ significantly at 35 and 37 °C compared to the control; however, there were increased levels of SOD, POD and MDA when the temperature was above 37 °C. These results suggest that thermal stress leads to oxidative stress and antioxidant enzymes play important roles in reducing oxidative damage in P. japonica adults. This study represents the first comprehensive report on the antioxidant defense system in predaceous coccinellids (the third trophic level). The findings provide useful information for predicting population dynamics and understanding the potential for P. japonica as a natural enemy to control pest insects under varied environmental conditions. PMID:25614965

  17. Elements of a national emergency response system for nuclear accidents

    SciTech Connect

    Dickerson, M.H.

    1987-02-10

    The purpose of this paper is to suggest elements for a general emergency response system, employed at a national level, to detect, evaluate and assess the consequences of a radiological atmospheric release occurring within or outside of national boundaries. These elements are focused on the total aspect of emergency response ranging from providing an initial alarm to a total assessment of the environmental and health effects. Elements of the emergency response system are described in such a way that existing resources can be directly applied if appropriate; if not, newly developed or an expansion of existing resources can be employed. The major thrust of this paper is toward a philosophical discussion and general description of resources that would be required to implementation. If the major features of this proposal system are judged desirable for implementation, then the next level of detail can be added. The philosophy underlying this paper is preparedness - preparedness through planning, awareness and the application of technology. More specifically, it is establishment of reasonable guidelines including the definition of reference and protective action levels for public exposure to accidents involving nuclear material; education of the public, government officials and the news media; and the application of models and measurements coupled to computer systems to address a series of questions related to emergency planning, response and assessment. It is the role of a proven national emergency response system to provide reliable, quality-controlled information to decision makers for the management of environmental crises.

  18. NFE2L2 variations reduce antioxidant response in patients with Parkinson disease

    PubMed Central

    Gui, YaXing; Zhang, LiShan; Lv, Wen; Zhang, WenMing; Zhao, JinJia; Hu, XingYue

    2016-01-01

    Oxidative stress has been recognized as a risk factor of Parkinson's disease (PD) development. We hypothesized that decreased function of the nuclear factor (erythroid-derived 2)-like 2 (NFE2L2)-antioxidant response element (ARE) pathway might predispose to Parkinsonism. A case-control study was performed between NFE2L2 Single Nucleotide Polymorphism (SNP) and PD in a cohort of 765 unrelated patients with diagnosis of PD and 489 matched normal individuals. We found that c.351T>A, D117E (P = 0.003, OR = 2.8) and c.351T>A, D117E (P = 0.012, OR = 1.9) were significantly associated with PD. The risk allele of both polymorphisms showed a high frequency in our PD sample (c.351A: 19.7% and c.423T: 7.8%). The association between both c.351T>A and c.423G>T and PD was further confirmed in an independent case-control cohort consisting of 210 individuals with PD and 148 normal controls. We further found that over expression of D117E and Q141H variants of NFE2L2 reduced target genes expression of Glutathione S-transferase Pi 1 (GSTP1), Glutathione S-transferase Mu 1 (GSTM1), and Heme oxygenase 1 (HO-1) genes. NFE2L2 D117E and Q141H impaired activation of ARE-driven transcriptional activity. Our findings indicate that NFE2L2 may play an important role in the pathogenesis of PD in Chinese populations. PMID:26887053

  19. Effect of diesel exhaust inhalation on antioxidant and oxidative stress responses in adults with metabolic syndrome

    PubMed Central

    Allen, Jason; Trenga, Carol A.; Peretz, Alon; Sullivan, Jeffrey H.; Carlsten, Christopher C.; Kaufman, Joel D.

    2011-01-01

    Background Traffic-related air pollution is associated with cardiovascular morbidity and mortality. Although the biological mechanisms are not well understood, oxidative stress may be a primary pathway. Subpopulations, such as individuals with metabolic syndrome (MeS), may be at increased risk of adverse effects associated with air pollution. Our aim was to assess the relationship between exposure to diesel exhaust (DE) and indicators of systemic antioxidant and oxidative responses in adults with MeS. We hypothesized that DE exposure would result in greater oxidative stress and antioxidant responses compared with filtered air (FA). Methods Ten adult subjects with MeS were exposed on separate days for two hours to FA or DE (at 200μg/m3), in a double blind, crossover experiment. Urinary 8-isoPGF2α (F2-isoprostanes), and 8-hydroxy-2′-deoxyguanosine (8-OHdG) were assessed as markers of oxidative stress at 3 hrs and 22 hrs, respectively, after exposure initiation. To assess the short-term antioxidant response we analyzed plasma ascorbic acid (AA) 90 minutes after exposure initiation. All outcomes were compared to pre-exposure levels, and mean changes were compared between FA and DE exposures. Results Mean changes in urinary F2-isoprostanes (ng/mg creatinine), (-0.05 [95% CI = −0.29, 0.15]), and 8-OHdG (μg/g creatinine) (-0.09 [-0.13, 0.31]), were not statistically significant. Mean changes in plasma AA (mg/dl) were also not significant (-0.02 [-0.78, 0.04]). Conclusions In this carefully controlled experiment, we did not detect significant changes in oxidative stress or systemic antioxidant responses in subjects with MeS exposed to 200μg/m3 DE. PMID:19852547

  20. Antioxidant supplementation increases retinal responses and decreases refractive error changes in dogs.

    PubMed

    Wang, Wei; Hernandez, Jerome; Moore, Cecil; Jackson, Janet; Narfström, Kristina

    2016-01-01

    The objective of the study was to examine whether a nutritional antioxidant supplementation could improve visual function in healthy dogs as measured by electroretinography (ERG) and autorefraction. A total of twelve Beagles, 6 to 8 years of age, with normal eyes upon indirect ophthalmoscopy and slit lamp biomicroscopy, were age and sex matched and randomly assigned to receive a feeding regimen for 6 months with or without a daily antioxidant supplementation. Portable, mini-Ganzfeld ERG and a Welch Allyn hand-held autorefractor were used to test retinal response and refractive error in the dogs at baseline and at the end of the supplementation period. All ERG a-wave amplitudes obtained were increased in the treatment group compared with those of dogs in the control group, with significant improvements in the scotopic high and photopic single flash cone ERG responses (P < 0·05 for both). For the b-wave amplitudes, all responses were similarly increased, with significant improvements in responses for the scotopic high light intensity stimulation (P < 0·05), and for photopic single flash cone and 30 Hz flicker (P < 0·01 for both) recordings. Change in refractive error was significantly less in the treatment group compared with that of the control group during the 6-month study (P < 0·05). Compared with the control group, the antioxidant-supplemented group showed improvement to varying degrees for retinal function and significantly less decline in refractive error. Dogs, like humans, experience retinal and lens functional decline with age. Antioxidant supplementation as demonstrated may be beneficial and effective in the long-term preservation and improvement of various functions of the canine eye. PMID:27293555

  1. Adaptive antioxidant response of manganese-superoxide dismutase following repetitive UVA irradiation.

    PubMed

    Poswig, A; Wenk, J; Brenneisen, P; Wlaschek, M; Hommel, C; Quel, G; Faisst, K; Dissemond, J; Briviba, K; Krieg, T; Scharffetter-Kochanek, K

    1999-01-01

    In response to the attack of reactive oxygen species, the skin has developed a complex antioxidant defense system including among others the manganese-superoxide dismutase (MnSOD). MnSOD dismutates the superoxide anion (O2*-) derived from the reduction of molecular oxygen to hydrogen peroxide (H2O2), which is detoxified by glutathione peroxidase to water and molecular oxygen. We have addressed the question whether MnSOD is inducible upon UVA irradiation and whether repetitive UV exposure, as practiced for the light-hardening during phototherapy of various photodermatoses, can even enhance the adaptive antioxidant response. Single exposure of four different strains of fibroblasts to UVA irradiation resulted in a dose- and time-dependent increase in specific MnSOD mRNA levels. Interestingly, repetitive UVA exposure at days 1, 2, and 3 at a dose rate of 200 kJ per m2 resulted in a 5-fold induction of specific MnSOD mRNA levels following the third UVA exposure. Similar results were obtained for MnSOD activity. This adaptive response in terms of upregulation of the antioxidant enzyme MnSOD correlates with the protection against high UV doses, if cells were preexposed to sublethal UV doses. Importantly, MnSOD substantially differed between the tested individuals in both mRNA and activity levels. Taken together, we here provide evidence for the increasing induction of MnSOD upon repetitive UVA irradiation that may contribute to the effective adaptive UVA response of the skin during light hardening in phototherapy. Interindividual differences in the inducibility of MnSOD might account for differences in the susceptibility to develop photodermatologic disorders related to photosensitivity, photoaging, and skin cancer. The molecular basis for interindividual differences in the inducibility of antioxidant enzymes remains to be elucidated. PMID:9886257

  2. Evaluation of trace elements, oxidant/antioxidant status, vitamin C and β-carotene in dogs with dermatophytosis.

    PubMed

    Beigh, S A; Soodan, J S; Singh, R; Khan, A M; Dar, M A

    2014-06-01

    The aim of the study was to determine zinc, copper and iron levels, erythrocyte oxidant/antioxidant status, vitamin C and β-carotene in dogs with dermatophytosis. A total of 23 dogs with clinically established diagnosis of dermatophytosis by trichogram and positive fungal culture and six dogs as control were included in this study. On cultural examination 52.17% fungal isolates were found to be Microsporum canis, 30.43% were Trichophyton mentagrophytes and 17.39% were M. gypseum. In comparison to healthy control, the dogs with dermatophytosis had significantly lower levels of zinc (P < 0.01), copper (P < 0.05), β-carotene and vitamin C levels (P < 0.05) and activities of superoxide dismutase (SOD) (P < 0.05) and catalase (P < 0.01), whereas the iron (P < 0.05) and malondialdehyde (MDA) (P < 0.01) levels were significantly increased. On correlation analysis, SOD activity was observed to be positively correlated (P < 0.05) with zinc and copper in both healthy and dermatophytosis affected dogs. In dermatophytosis affected dogs the MDA levels were negatively correlated (P < 0.05) with iron, β-carotene levels and the activities of antioxidant enzymes; SOD and catalase. Our results demonstrated that dermatophytosis in dogs is associated with significant alteration in oxidant/antioxidant balance and trace elements. It might be secondary consequence of dermatophytosis infection or contributing factor in its pathogenesis.

  3. Photoprotection by dietary phenolics against melanogenesis induced by UVA through Nrf2-dependent antioxidant responses

    PubMed Central

    Chaiprasongsuk, Anyamanee; Onkoksoong, Tasanee; Pluemsamran, Thanyawan; Limsaengurai, Saowalak; Panich, Uraiwan

    2015-01-01

    Dietary phenolics may play a protective role in UV-mediated skin pigmentation through their antioxidant and UV-absorbing actions. In this study, we investigated whether genetic silencing of Nrf2, regulating the transcription of antioxidant genes, affected melanogenesis in primary human epidermal melanocytes (HEMn) and B16F10 melanoma cells subjected to UVA (8 J/cm2) exposure. Then, we explored the antimelanogenic actions of phenolics; caffeic acid (CA) and ferulic acid (FA) providing partial UVA protection; quercetin (QU) and rutin (RU) providing strong UVA protection and; avobenzone (AV), an efficient UVA filter, in association with modulation of Nrf2-mediated antioxidant defenses in response to UVA insults in B16F10 cells. Upon oxidative insults, Nrf2 silencing promoted melanogenesis in both HEMn and B16F10 cells irradiated with UVA. Stimulation of melanogenesis by UVA correlated with increased ROS and oxidative DNA damage (8-OHdG), GSH depletion as well as a transient downregulation of Nrf2 nuclear translocation and of Nrf2-ARE signaling in B16F10 cells. All test compounds exerted antimelanogenic effects with respect to their abilities to reverse UVA-mediated oxidative damage as well as downregulation of Nrf2 activity and its target antioxidants (GCLC, GST and NQO1) in B16F10 cells. In conclusion, defective Nrf2 may promote melanogenesis under UVA irradiation through oxidative stress mechanisms. Compounds with antioxidant and/or UVA absorption properties could protect against UVA-induced melanogenesis through indirect regulatory effect on Nrf2-ARE pathway. PMID:26765101

  4. Photoprotection by dietary phenolics against melanogenesis induced by UVA through Nrf2-dependent antioxidant responses.

    PubMed

    Chaiprasongsuk, Anyamanee; Onkoksoong, Tasanee; Pluemsamran, Thanyawan; Limsaengurai, Saowalak; Panich, Uraiwan

    2016-08-01

    Dietary phenolics may play a protective role in UV-mediated skin pigmentation through their antioxidant and UV-absorbing actions. In this study, we investigated whether genetic silencing of Nrf2, regulating the transcription of antioxidant genes, affected melanogenesis in primary human epidermal melanocytes (HEMn) and B16F10 melanoma cells subjected to UVA (8J/cm(2)) exposure. Then, we explored the antimelanogenic actions of phenolics; caffeic acid (CA) and ferulic acid (FA) providing partial UVA protection; quercetin (QU) and rutin (RU) providing strong UVA protection and; avobenzone (AV), an efficient UVA filter, in association with modulation of Nrf2-mediated antioxidant defenses in response to UVA insults in B16F10 cells. Upon oxidative insults, Nrf2 silencing promoted melanogenesis in both HEMn and B16F10 cells irradiated with UVA. Stimulation of melanogenesis by UVA correlated with increased ROS and oxidative DNA damage (8-OHdG), GSH depletion as well as a transient downregulation of Nrf2 nuclear translocation and of Nrf2-ARE signaling in B16F10 cells. All test compounds exerted antimelanogenic effects with respect to their abilities to reverse UVA-mediated oxidative damage as well as downregulation of Nrf2 activity and its target antioxidants (GCLC, GST and NQO1) in B16F10 cells. In conclusion, defective Nrf2 may promote melanogenesis under UVA irradiation through oxidative stress mechanisms. Compounds with antioxidant and/or UVA absorption properties could protect against UVA-induced melanogenesis through indirect regulatory effect on Nrf2-ARE pathway. PMID:26765101

  5. Physiological and Antioxidant Responses in Wheat (Triticum aestivum) to HHCB in Soil.

    PubMed

    Chen, Cuihong; Cai, Zhang

    2015-08-01

    Seedlings of wheat (Triticum aestivum) were exposed in soil to the polycyclic musk chemical, 1,3,4,6,7,8-hexahydro-4,6,6,7,8,8-hexamethylcyclopenta[g]-2-benzopyran (HHCB) for 21 days, to evaluate its effect upon chlorophyll (CHL), lipid peroxidation and the antioxidant system. The content of CHL in leaves was inhibited significantly after 14- and 21-days exposures, whereas it was significantly induced by a low level of HHCB after a 7-days exposure. The content of malondialdehyde (MDA) in wheat leaves increased with an increase in the concentration of HHCB in soil, indicating that oxidative stress could be induced by HHCB. Moreover, HHCB exposure induced significant antioxidant responses in wheat. The activities of superoxide dismutase (SOD), catalase (CAT) and peroxidase (POD) in wheat leaves were induced by HHCB after 14 and 21 days of exposure. However, the changing trend of the antioxidant enzymes in wheat roots was different from that in leaves. The results suggested that the assayed parameters of T. aestivum could be used as responsive biomarkers for oxidative stress in the soil environment.

  6. Spectral response of multi-element silicon detectors

    SciTech Connect

    Ludewigt, B.A.; Rossington, C.S.; Chapman, K.

    1997-04-01

    Multi-element silicon strip detectors, in conjunction with integrated circuit pulse-processing electronics, offer an attractive alternative to conventional lithium-drifted silicon Si(Li) and high purity germanium detectors (HPGe) for high count rate, low noise synchrotron x-ray fluorescence applications. One of the major differences between the segmented Si detectors and the commercially available single-element Si(Li) or HPGe detectors is that hundreds of elements can be fabricated on a single Si substrate using standard silicon processing technologies. The segmentation of the detector substrate into many small elements results in very low noise performance at or near, room temperature, and the count rate of the detector is increased many-fold due to the multiplication in the total number of detectors. Traditionally, a single channel of detector with electronics can handle {approximately}100 kHz count rates while maintaining good energy resolution; the segmented detectors can operate at greater than MHz count rates merely due to the multiplication in the number of channels. One of the most critical aspects in the development of the segmented detectors is characterizing the charge sharing and charge loss that occur between the individual detector strips, and determining how these affect the spectral response of the detectors.

  7. Antioxidant responses in Phanerochaete chrysosporium exposed to Astrazone Red FBL textile dye.

    PubMed

    Demirci, Ozlem; Hamamcı, Dilek Asma

    2013-01-01

    Interest in environmental-pollutant-induced oxidative stress and knowledge of the interactions between reactive oxygen species and cellular systems have increased in toxicology and microbial ecology considerably in recent decades. These reactive oxidants are produced by a variety of environmental sources: ionizing radiations, ultraviolet light, redox cycling drugs, hyperoxia, ischemia and redox-active xenobiotics or during metabolism of environmental pollutants, such as heavy metals in mining industries, dyes in wastewater of textile industries, pesticides and polycyclic hydrocarbons, i.e. foreign materials. In this study, the effect of dye on the antioxidative defence system of Phanerochaete chrysosporium was investigated, and we showed the ability of Phanerochaete chrysosporium to antioxidative response and defence system exposed to Astrazone Red FBL. Catalase, glutathione reductase, glutathione s-transferase activities and level of glutathione decreased, depending on the period of growth in each exposure to low and high concentration group (20 and 50 ppm) compared with the control group.

  8. Antioxidant and Vasodilator Activity of Ugni molinae Turcz. (Murtilla) and Its Modulatory Mechanism in Hypotensive Response

    PubMed Central

    Jofré, Ignacio; Pezoa, Cesar; Scheuermann, Erick; Rosalen, Pedro Luiz; Romero, Fernando

    2016-01-01

    Hypertension is a systemic condition with high morbidity and mortality rates worldwide, which poses an increased risk for cardiovascular diseases. In this study, we demonstrated the antioxidant and vasodilator activity of Ugni molinae Turcz. (Murtilla) fruit, a berry native to Chile and proposed models to explain its modulatory mechanism in hypotensive response. Murtilla fruits were cultivated in a germplasm bank and submitted to chemical and biological analyses. The phenolic compounds gallic acid, Catechin, Quercetin-3-β-D-glucoside, Myricetin, Quercetin, and Kaempferol were identified. Murtilla extract did not generate toxic effects on human endothelial cells and had significant antioxidant activity against ROS production, lipid peroxidation, and superoxide anion production. Furthermore, it showed dose-dependent vasodilator activity in aortic rings in the presence of endothelium, whose hypotensive mechanism is partially mediated by nitric oxide synthase/guanylate cyclase and large-conductance calcium-dependent potassium channels. Murtilla fruits might potentially have beneficial effects on the management of cardiovascular diseases.

  9. Antioxidant and Vasodilator Activity of Ugni molinae Turcz. (Murtilla) and Its Modulatory Mechanism in Hypotensive Response

    PubMed Central

    Jofré, Ignacio; Pezoa, Cesar; Scheuermann, Erick; Rosalen, Pedro Luiz; Romero, Fernando

    2016-01-01

    Hypertension is a systemic condition with high morbidity and mortality rates worldwide, which poses an increased risk for cardiovascular diseases. In this study, we demonstrated the antioxidant and vasodilator activity of Ugni molinae Turcz. (Murtilla) fruit, a berry native to Chile and proposed models to explain its modulatory mechanism in hypotensive response. Murtilla fruits were cultivated in a germplasm bank and submitted to chemical and biological analyses. The phenolic compounds gallic acid, Catechin, Quercetin-3-β-D-glucoside, Myricetin, Quercetin, and Kaempferol were identified. Murtilla extract did not generate toxic effects on human endothelial cells and had significant antioxidant activity against ROS production, lipid peroxidation, and superoxide anion production. Furthermore, it showed dose-dependent vasodilator activity in aortic rings in the presence of endothelium, whose hypotensive mechanism is partially mediated by nitric oxide synthase/guanylate cyclase and large-conductance calcium-dependent potassium channels. Murtilla fruits might potentially have beneficial effects on the management of cardiovascular diseases. PMID:27688827

  10. Effect of Nrf2 on rat ovarian tissues against atrazine-induced anti-oxidative response.

    PubMed

    Zhao, Fan; Li, Kun; Zhao, Lijing; Liu, Jian; Suo, Qi; Zhao, Jing; Wang, Hebin; Zhao, Shuhua

    2014-01-01

    The environmental persistence and bioaccumulation of herbicide atrazine may pose a significant threat to human health. In this experiment, Wistar rats were treated by 5, 25 and 125 mg·kg(-1) atrazine respectively for 28 days, and the oxidative stress responses as well as the activations of Nrf2 signaling pathway in ovarian tissues induced by atrazine were observed. The results showed that after be treated by atrazine, the proportion of atretic follicles in the rat ovary were increased, the contents of NO and MDA in the tissue homogenates were increased, the over-expressed Nrf2 transferred into the nuclei and played an antioxidant role by up-regulated the expression of II phase detoxifying enzymes such as HO1 and NQO1 and the expression of antioxidant enzymes such as CAT, SOD and GSH-PX.

  11. Early antioxidative defence responses in the aquatic worms (Limnodrilus sp.) in Porsuk Creek in Eskisehir (Turkey).

    PubMed

    Oztetik, Elif; Cicek, Arzu; Arslan, Naime

    2013-07-01

    Certain oligochaeta specimens have been universally applied as bioindicators to reflect the organic and inorganic pollution in rivers and play a major role in the decomposition of pollutants. The aim of this study was to investigate the water quality in Porsuk Creek in Eskisehir (Turkey) through the specimens from two different species that belong to Limnodrilus genus, using their biomonitoring compatibilities for the accumulated trace element concentrations and to describe the applicability of antioxidative systems as biomarkers of pollution in Tubificinae. Therefore, some parameters that serve as biomarkers for antioxidative defence, total protein, glutathione (GSH) contents and glutathione S-transferase (GST) activities, were determined in Limnodrilus hoffmeisteri and Limnodrilus udekemianus. The study was completed with the chemical analysis of the trace elements from these specimens and also from the water samples. As a conclusion, the observed elevation in GSH levels and GST activities reflect the contribution of oxidative stress in toxicity mechanisms due to the accumulation of trace elements, and the study also suggests a general induction of detoxification metabolisms in the presence of several pollutants in benthic sediment-dwelling worms. According to the average value, the trace element levels for two species are as follows: Fe > Al > Zn > Mn > Pb > Cu > Ni > B > Cd = Cr = Hg. As Porsuk Creek is used for many purposes, such as irrigation, drinking water and fish production, discharges of all types of wastes should be under stringent control to avoid the unwanted health effects to its habitants and to humans. PMID:22514119

  12. Early antioxidative defence responses in the aquatic worms (Limnodrilus sp.) in Porsuk Creek in Eskisehir (Turkey).

    PubMed

    Oztetik, Elif; Cicek, Arzu; Arslan, Naime

    2013-07-01

    Certain oligochaeta specimens have been universally applied as bioindicators to reflect the organic and inorganic pollution in rivers and play a major role in the decomposition of pollutants. The aim of this study was to investigate the water quality in Porsuk Creek in Eskisehir (Turkey) through the specimens from two different species that belong to Limnodrilus genus, using their biomonitoring compatibilities for the accumulated trace element concentrations and to describe the applicability of antioxidative systems as biomarkers of pollution in Tubificinae. Therefore, some parameters that serve as biomarkers for antioxidative defence, total protein, glutathione (GSH) contents and glutathione S-transferase (GST) activities, were determined in Limnodrilus hoffmeisteri and Limnodrilus udekemianus. The study was completed with the chemical analysis of the trace elements from these specimens and also from the water samples. As a conclusion, the observed elevation in GSH levels and GST activities reflect the contribution of oxidative stress in toxicity mechanisms due to the accumulation of trace elements, and the study also suggests a general induction of detoxification metabolisms in the presence of several pollutants in benthic sediment-dwelling worms. According to the average value, the trace element levels for two species are as follows: Fe > Al > Zn > Mn > Pb > Cu > Ni > B > Cd = Cr = Hg. As Porsuk Creek is used for many purposes, such as irrigation, drinking water and fish production, discharges of all types of wastes should be under stringent control to avoid the unwanted health effects to its habitants and to humans.

  13. Characterization and response of antioxidant systems in the tissues of the freshwater pond snail (Lymnaea stagnalis) during acute copper exposure.

    PubMed

    Atli, Gülüzar; Grosell, Martin

    2016-07-01

    The response of enzymatic (superoxide dismutase, SOD; catalase, CAT; glutathione peroxidase, GPX and glutathione reductase, GR) and non-enzymatic responses (glutathione, GSH, oxidized glutathione, GSSG and GSH/GSSG) against acute Cu toxicity (2-90μg/mL for 48h) in different tissues of Lymnaea stagnalis were measured. Incubation conditions for enzymatic activity measurements were optimized for L. stagnalis tissues. Three examined tissues, the hepatopancreas, the foot muscle and the mantle, exhibited variable responses in antioxidant parameters as a function of Cu concentrations. The most responsive antioxidant enzymes were GPX and CAT while GR appeared less sensitive. In general antioxidant enzymes at higher Cu concentrations though GSH levels at lower Cu concentrations exhibited the greatest changes in hepatopancreas and foot muscle, respectively. All antioxidant enzymes except GR increased after exposure to the highest Cu concentration in mantle. Total and reduced GSH increased in hepatopancreas but decreased with GSH/GSSG ratios at all Cu concentrations in foot muscle. The present results show that antioxidants respond to acute Cu exposure at concentrations as low as 2μg Cu/L in adult L. stagnalis with variable responses in different tissues. Antioxidants both including enzymatic and non-enzymatic parameters may account, in part, for the high tolerance to acute metal exposure observed in adult L. stagnalis and could form suited biomarkers to evaluate the metal exposure and toxicity in aquatic environment even at relatively low level short term exposure. PMID:27108202

  14. Salinity and drought induced antioxidant responses in different cultivars of safflower (Carthamus tinctorius L.).

    PubMed

    Javed, Sadia; Ashraf, Muhammad Yasin; Meraj, Munazzah; Bukhari, Shazia Anwer; Zovia, Iram

    2013-01-01

    Six cultivars of safflower which were (PI-387820, PI-251978, PI-170274, PI-387821, PI-386174 and Thori-78) grown in net house of NIAB under salinity (10 ds m⁻¹) and drought (60% field capacity) conditions and compared to their oxidative damage and antioxidative responses. Plant samples (leaves) were collected for the determination of malonidialdehyde (MDA), antioxidative enzymes (catalase, ascorbate peroxidase, glutathione reductase, and peroxidase), proline, and photosynthetic pigments. Salinity and drought decreased the chlorophyll a and b contents but a decrease in chlorophyll a and b was less in safflower variety (THORI-78) which could be a useful marker for selecting a stress tolerant variety. Both stresses considerable increases the accumulation of proline in PI-251978, PI-170274, PI-387821, PI-386174 and THORI-78 varieties of safflower whereas the proline accumulation did not appear to be an essential part of the protection mechanism against salinity and drought in variety PI-387820. Enzyme activity measurements revealed that THORI-78 can tolerate salinity and drought stress well by increasing the activity of catalase and APX enzymes whereas variety PI- 386174 showed increased activity of glutathione reductase enzyme under salinity and drought and appear to be very crucial antioxidative defenses during intense stress conditions. The results indicate that the photosynthetic pigments, proline and activities of the enzymes are important mechanism for the stress tolerance in safflower plant and can be considered as genetic improvement for the plant in salinity and drought soil conditions.

  15. Root antioxidant responses of two Pisum sativum cultivars to direct and induced Fe deficiency.

    PubMed

    Jelali, N; Donnini, S; Dell'Orto, M; Abdelly, C; Gharsalli, M; Zocchi, G

    2014-05-01

    The contribution of antioxidant defence systems in different tolerance to direct and bicarbonate-induced Fe deficiency was evaluated in two pea cultivars (Kelvedon, tolerant and Lincoln, susceptible). Fe deficiency enhanced lipid peroxidation and H2 O2 concentration in roots of both cultivars, particularly in the sensitive one grown under bicarbonate supply. The results obtained on antioxidant activities (SOD, CAT, POD) suggest that H2 O2 accumulation could be due to an overproduction of this ROS and, at the same time, to a poor capacity to detoxify it. Moreover, under bicarbonate supply the activity of POD isoforms was reduced only in the sensitive cultivar, while in the tolerant one a new isoform was detected, suggesting that POD activity might be an important contributor to pea tolerance to Fe deficiency. The presence of bicarbonate also resulted in stimulation of GR, MDHAR and DHAR activities, part of the ASC-GSH pathway, which was higher in the tolerant cultivar than in the sensitive one. Overall, while in the absence of Fe only slight differences were reported between the two cultivars, the adaptation of Kelvedon to the presence of bicarbonate seems to be related to its greater ability to enhance the antioxidant response at the root level.

  16. Responses of Noccaea caerulescens and Lupinus albus in trace elements-contaminated soils.

    PubMed

    Martínez-Alcalá, Isabel; Hernández, Luis E; Esteban, Elvira; Walker, David J; Bernal, M Pilar

    2013-05-01

    Plants exposed to trace elements can suffer from oxidative stress, which is characterised by the accumulation of reactive oxygen species, alteration in the cellular antioxidant defence system and ultimately lipid peroxidation. We assessed the most-appropriate stress indexes to describe the response of two plant species, with different strategies for coping with trace elements (TEs), to particular contaminants. Noccaea caerulescens, a hyperaccumulator, and Lupinus albus, an excluder, were grown in three soils of differing pH: an acidic soil, a neutral soil (both contaminated mainly by Cu, Zn and As) and a control soil. Then, plant stress indicators were measured. As expected, N. caerulescens accumulated higher levels of Zn and Cd in shoots than L. albus, this effect being stronger in the acid soil, reflecting greater TE solubility in this soil. However, the shoot concentrations of Mn were higher in L. albus than in N. caerulescens, while the As concentration was similar in the two species. In L. albus, the phenolic content and lipid peroxidation were related with the Cu concentration, whereas the Zn and Cd concentrations in N. caerulescens were more closely related to glutathione content and lipid peroxidation. Interestingly, phytochelatins were only found in L. albus grown in polluted soils. Hence, the two species differed with respect to the TEs which provoked stress and the biochemical indicators of the stress, there being a close relationship between the accumulation of TEs and their associated stress indicators in the different plant organs.

  17. The Different Physiological and Antioxidative Responses of Zucchini and Cucumber to Sewage Sludge Application.

    PubMed

    Wyrwicka, Anna; Urbaniak, Magdalena

    2016-01-01

    The present study investigates the effect of soil amended with sewage sludge on oxidative changes in zucchini and cucumber plants (Cucurbitaceae) and the consequent activation of their antioxidative systems and detoxification mechanisms. The plants were grown in pots containing soil amended with three concentrations of sewage sludge (1.8 g, 5.4 g and 10.8 g per pot), while controls were potted with vegetable soil. The activities of three antioxidative enzymes, ascorbate peroxidase (APx), catalase (CAT) and guaiacol peroxidase (POx), were assessed, as well as of the detoxifying enzyme S-glutathione transferase (GST). Lipid peroxidation was evaluated by measuring the extent of oxidative damage; α-tocopherol content, the main lipophilic antioxidant, was also measured. Visible symptoms of leaf blade damage after sewage sludge application occurred only on the zucchini plants. The zucchini and cucumber plants showed a range of enzymatic antioxidant responses to sewage sludge application. While APx and POx activities increased significantly with increasing sludge concentration in the zucchini plants, they decreased in the cucumber plants. Moreover, although the activity of these enzymes increased gradually with increasing doses of sewage sludge, these levels fell at the highest dose. An inverse relationship between peroxidases activity and CAT activity was observed in both investigated plant species. In contrast, although GST activity increased progressively with sludge concentration in both the zucchini and cucumber leaves, the increase in GST activity was greater in the zucchini plants, being visible at the lowest dose used. The results indicate that signs of sewage sludge toxicity were greater in zucchini than cucumber, and its defense reactions were mainly associated with increases in APx, POx and GST activity. PMID:27327659

  18. Salt tolerance is related to a specific antioxidant response in the halophyte cordgrass, Spartina densiflora

    NASA Astrophysics Data System (ADS)

    Canalejo, Antonio; Martínez-Domínguez, David; Córdoba, Francisco; Torronteras, Rafael

    2014-06-01

    Halophytes usually have a robust antioxidative defense system to alleviate oxidative damage during salt stress. Spartina densiflora is a colonizing halophyte cordgrass, native of South America, which has become a common species in salt marshes of northern hemisphere, where it is ousting indigenous species. This study addressed salinity stress in S. densiflora; the occurrence of oxidative stress and the possible involvement of the antioxidative system in its high salt tolerance were studied. Plants were evaluated at in situ conditions, in the laboratory during a 28 day-acclimation period (AP) in clean substrate irrigated with a control salt content of 4 g L-1 (68 mM) and during a subsequent 28 day-treatment period (TP) exposed to different NaCl concentrations: control (68 mM), 428 mM or 680 mM. In the in situ setting, the high leave Na+ content was accompanied by high levels of hydroperoxides and reduced levels of total chlorophyll and carotenes, which correlated with enhanced activation of antioxidant defense biomarkers as total ascorbic acid (AA) content and guaiacol peroxidase (POD: EC 1.11.1.7)), catalase (CAT: EC 1.11.1.6) and ascorbate peroxidase (APX: EC 1.11.1.11) activities. Throughout the AP, leave Na+ and oxidative stress markers decreased concomitantly and reached stable low levels. During the TP, dose and time-dependent accumulation of Na+ in high NaCl-treated plants was concurrent with a decrease in content of total chlorophyll and carotenes and with an increase in the levels of total AA and CAT and APX activities. In conclusion, as hypothesized, high salinity induces conditions of oxidative stress in S. densiflora, so that its salt tolerance appears to be related to the implementation of a specific antioxidant response. This may account for Spartina densiflora's successful adaptation to habitats with fluctuating salinity and favour its phytoremediation potential.

  19. The Different Physiological and Antioxidative Responses of Zucchini and Cucumber to Sewage Sludge Application

    PubMed Central

    Wyrwicka, Anna; Urbaniak, Magdalena

    2016-01-01

    The present study investigates the effect of soil amended with sewage sludge on oxidative changes in zucchini and cucumber plants (Cucurbitaceae) and the consequent activation of their antioxidative systems and detoxification mechanisms. The plants were grown in pots containing soil amended with three concentrations of sewage sludge (1.8 g, 5.4 g and 10.8 g per pot), while controls were potted with vegetable soil. The activities of three antioxidative enzymes, ascorbate peroxidase (APx), catalase (CAT) and guaiacol peroxidase (POx), were assessed, as well as of the detoxifying enzyme S-glutathione transferase (GST). Lipid peroxidation was evaluated by measuring the extent of oxidative damage; α-tocopherol content, the main lipophilic antioxidant, was also measured. Visible symptoms of leaf blade damage after sewage sludge application occurred only on the zucchini plants. The zucchini and cucumber plants showed a range of enzymatic antioxidant responses to sewage sludge application. While APx and POx activities increased significantly with increasing sludge concentration in the zucchini plants, they decreased in the cucumber plants. Moreover, although the activity of these enzymes increased gradually with increasing doses of sewage sludge, these levels fell at the highest dose. An inverse relationship between peroxidases activity and CAT activity was observed in both investigated plant species. In contrast, although GST activity increased progressively with sludge concentration in both the zucchini and cucumber leaves, the increase in GST activity was greater in the zucchini plants, being visible at the lowest dose used. The results indicate that signs of sewage sludge toxicity were greater in zucchini than cucumber, and its defense reactions were mainly associated with increases in APx, POx and GST activity. PMID:27327659

  20. Hepatic antioxidative responses to PCDPSs and estimated short-term biotoxicity in freshwater fish.

    PubMed

    Li, Ying; Li, Mei; Shi, Jiaqi; Yang, Xi; Wang, Zunyao

    2012-09-15

    This study evaluated the short-term toxicity of polychlorinated diphenylsulfides (PCDPSs) in freshwater fish. Laboratory experiments were performed to determine the oxidative stress and antioxidative responses of 12 different types of PCDPSs in the liver of goldfish, Carassius auratus. Fish were injected with increasing concentrations (0.1, 1, 10, 100 μg/kg body weight for various PCDPSs and 1, 10, 100 mg/kg for diphenylsulfides (DPS)) of test compounds for 12h, with one group assigned as the control. We simultaneously evaluated the time-dependent effects of PCDPSs on the antioxidant defense system, using Tris-, Penta- and Hepta-CDPS. Fish were acutely injected with either 10 μg/kg of such PCDPSs or corn oil alone (control), and then liver samples were collected at 0.5, 1, 2, 3 and 5d for analysis of antioxidant content. Changes in the activities of superoxide dismutase (SOD), catalase (CAT), and in the levels of malondialdehyde (MDA) were detected, suggesting that PCDPSs exhibit potential biotoxicity. In addition, our data indicated that PCDPS toxicity varies with the degree of substitution and the position of substitution attached to two benzene rings, results that were also partly supported by the time-dependent effects elicited by the Tris-, Penta- and Hepta-CDPSs. In particular, our results indicate that Penta- and Hexa-CDPSs may act as highly toxic contaminants that exhibit striking enzymatic inhibitory activity. Furthermore, our results suggest that altered levels of antioxidant enzymes, including SOD and CAT, along with MDA, may serve as potential biomarkers of PCDPS contamination. PMID:22640874

  1. The Different Physiological and Antioxidative Responses of Zucchini and Cucumber to Sewage Sludge Application.

    PubMed

    Wyrwicka, Anna; Urbaniak, Magdalena

    2016-01-01

    The present study investigates the effect of soil amended with sewage sludge on oxidative changes in zucchini and cucumber plants (Cucurbitaceae) and the consequent activation of their antioxidative systems and detoxification mechanisms. The plants were grown in pots containing soil amended with three concentrations of sewage sludge (1.8 g, 5.4 g and 10.8 g per pot), while controls were potted with vegetable soil. The activities of three antioxidative enzymes, ascorbate peroxidase (APx), catalase (CAT) and guaiacol peroxidase (POx), were assessed, as well as of the detoxifying enzyme S-glutathione transferase (GST). Lipid peroxidation was evaluated by measuring the extent of oxidative damage; α-tocopherol content, the main lipophilic antioxidant, was also measured. Visible symptoms of leaf blade damage after sewage sludge application occurred only on the zucchini plants. The zucchini and cucumber plants showed a range of enzymatic antioxidant responses to sewage sludge application. While APx and POx activities increased significantly with increasing sludge concentration in the zucchini plants, they decreased in the cucumber plants. Moreover, although the activity of these enzymes increased gradually with increasing doses of sewage sludge, these levels fell at the highest dose. An inverse relationship between peroxidases activity and CAT activity was observed in both investigated plant species. In contrast, although GST activity increased progressively with sludge concentration in both the zucchini and cucumber leaves, the increase in GST activity was greater in the zucchini plants, being visible at the lowest dose used. The results indicate that signs of sewage sludge toxicity were greater in zucchini than cucumber, and its defense reactions were mainly associated with increases in APx, POx and GST activity.

  2. The response of antioxidant systems in Nostoc sphaeroides against UV-B radiation and the protective effects of exogenous antioxidants

    NASA Astrophysics Data System (ADS)

    Wang, Gaohong; Hu, Chunxiang; Li, Dunhai; Zhang, Delu; Li, Xiaoyan; Chen, Kun; Liu, Yongding

    UV radiation is one of many harmful factors found in space that are detrimental to organisms on earth in space exploration. In the present work, we examined the role of antioxidant system in Nostoc sphaeroides Kütz (Cyanobacterium) and the effects of exogenously applied antioxidant molecules on its photosynthetic rate under UV-B radiation. It was found that UV-B radiation promoted the activity of antioxidant system to protect photosystem II (PSII) and exogenously applied antioxidant: sodium nitroprusside (SNP) and N-acetylcysteine (NAC) had an obvious protection on PSII activity under UV-B radiation. The activity of superoxide dismutase (SOD, EC 1.15.1.1), catalase (CAT, EC 1.11.1.6), peroxidase (POD, EC 1.11.1.7) and content of MDA (malondialdehyde) and ASC (ascorbate) were improved by 0.5 mM and 1 mM SNP, but 0.1 mM SNP decreased the activity of antioxidant system. Addition of exogenous NAC decreased the activity of SOD, POD, CAT and the content MDA and ASC. In contrast, exogenously applied NAC increased GSH content. The results suggest that exogenous SNP and NAC may protect algae by different mechanisms: SNP may play double roles as both sources of reactive free radicals as well as ROS scavengers in mediating the protective role of PSII on algae under UV-B radiation. On the other hand, NAC functions as an antioxidant or precursor of glutathione, which could protect PSII directly from UV-B radiation.

  3. Antioxidative stress responses in the floating macrophyte Lemna minor L. with cylindrospermopsin exposure.

    PubMed

    Flores-Rojas, Nelida Cecilia; Esterhuizen-Londt, Maranda; Pflugmacher, Stephan

    2015-12-01

    Cylindrospermopsin toxicity and oxidative stress have been examined in aquatic animals, however, only a few studies with aquatic plants have been conducted focusing on the potential for bioaccumulation of cylindrospermopsin. The oxidative stress effects caused by cylindrospermopsin on macrophytes have not yet been specifically studied. The oxidative stress response of Lemna minor L. with exposure to cylindrospermopsin, was therefore tested in this study. The hydrogen peroxide concentration together with the activities of the antioxidant enzymes (catalase, peroxidase, glutathione reductase and glutathione S-transferase) were determined after 24h (hours) of exposure to varying concentrations (0.025, 0.25, 2.5 and 25μg/L) of cylindrospermopsin. Responses with longer exposure periods (48, 96, 168h) were tested only with exposure to 2.5 and 25μg/L cylindrospermopsin. Additionally, the content of the carotenoids was determined as a possible non-enzymatic antioxidant defence mechanism against cylindrospermopsin. The levels of hydrogen peroxide increased after 24h even at the lowest cylindrospermopsin exposure concentrations. Catalase showed the most representative antioxidant response observed after 24h and maintained its activity throughout the experiment. Catalase activity corresponded with the contents of hydrogen peroxide at 2.5 and 25μg/L cylindrospermopsin. The data suggest that glutathione S-transferase, glutathione reductase and the carotenoid content act together with catalase but are more sensitive to higher concentrations of cylindrospermopsin and after a longer exposure period (168h). The results indicate that cylindrospermopsin promotes oxidative stress in L. minor at concentrations of 2.5 and 25μg/L. However, L. minor has sufficient defence mechanisms in place against this cyanobacterial toxin. Even though L. minor exhibits the potential to managing and control cylindrospermopsin contamination in aquatic systems, further studies in tolerance limits to

  4. Antioxidative stress responses in the floating macrophyte Lemna minor L. with cylindrospermopsin exposure.

    PubMed

    Flores-Rojas, Nelida Cecilia; Esterhuizen-Londt, Maranda; Pflugmacher, Stephan

    2015-12-01

    Cylindrospermopsin toxicity and oxidative stress have been examined in aquatic animals, however, only a few studies with aquatic plants have been conducted focusing on the potential for bioaccumulation of cylindrospermopsin. The oxidative stress effects caused by cylindrospermopsin on macrophytes have not yet been specifically studied. The oxidative stress response of Lemna minor L. with exposure to cylindrospermopsin, was therefore tested in this study. The hydrogen peroxide concentration together with the activities of the antioxidant enzymes (catalase, peroxidase, glutathione reductase and glutathione S-transferase) were determined after 24h (hours) of exposure to varying concentrations (0.025, 0.25, 2.5 and 25μg/L) of cylindrospermopsin. Responses with longer exposure periods (48, 96, 168h) were tested only with exposure to 2.5 and 25μg/L cylindrospermopsin. Additionally, the content of the carotenoids was determined as a possible non-enzymatic antioxidant defence mechanism against cylindrospermopsin. The levels of hydrogen peroxide increased after 24h even at the lowest cylindrospermopsin exposure concentrations. Catalase showed the most representative antioxidant response observed after 24h and maintained its activity throughout the experiment. Catalase activity corresponded with the contents of hydrogen peroxide at 2.5 and 25μg/L cylindrospermopsin. The data suggest that glutathione S-transferase, glutathione reductase and the carotenoid content act together with catalase but are more sensitive to higher concentrations of cylindrospermopsin and after a longer exposure period (168h). The results indicate that cylindrospermopsin promotes oxidative stress in L. minor at concentrations of 2.5 and 25μg/L. However, L. minor has sufficient defence mechanisms in place against this cyanobacterial toxin. Even though L. minor exhibits the potential to managing and control cylindrospermopsin contamination in aquatic systems, further studies in tolerance limits to

  5. The enzymatic and antioxidative stress response of Lemna minor to copper and a chloroacetamide herbicide.

    PubMed

    Obermeier, Michael; Schröder, Christian A; Helmreich, Brigitte; Schröder, Peter

    2015-12-01

    Lemna minor L., a widely used model plant for toxicity tests has raised interest for its application to phytoremediation due to its rapid growth and ubiquitous occurrence. In rural areas, the pollution of water bodies with heavy metals and agrochemicals poses a problem to surface water quality. Among problematic compounds, heavy metals (copper) and pesticides are frequently found in water bodies. To establish duckweed as a potential plant for phytoremediation, enzymatic and antioxidative stress responses of Lemna minor during exposure to copper and a chloroacetamide herbicide were investigated in laboratory studies. The present study aimed at evaluating growth and the antioxidative and glutathione-dependent enzyme activity of Lemna plants and its performance in a scenario for phytoremediation of copper and a chloroacetamide herbicide. Lemna minor was grown in Steinberg medium under controlled conditions. Plants were treated with CuSO4 (ion conc. 50 and 100 μg/L) and pethoxamide (1.25 and 2.5 μg/L). Measurements following published methods focused on plant growth, oxidative stress, and basic detoxification enzymes. Duckweed proved to survive treatment with the respective concentrations of both pollutants very well. Its growth was inhibited scarcely, and no visible symptoms occurred. On the cellular basis, accumulation of O2(-) and H2O2 were detected, as well as stress reactions of antioxidative enzymes. Duckweed detoxification potential for organic pollutants was high and increased significantly with incubation. Pethoxamide was found to be conjugated with glutathione. Copper was accumulated in the fronds at high levels, and transient oxidative defense reactions were triggered. This work confirms the significance of L. minor for the removal of copper from water and the conjugation of the selective herbicide pethoxamide. Both organic and inorganic xenobiotics induced different trends of enzymatic and antioxidative stress response. The strong increase of stress

  6. The enzymatic and antioxidative stress response of Lemna minor to copper and a chloroacetamide herbicide.

    PubMed

    Obermeier, Michael; Schröder, Christian A; Helmreich, Brigitte; Schröder, Peter

    2015-12-01

    Lemna minor L., a widely used model plant for toxicity tests has raised interest for its application to phytoremediation due to its rapid growth and ubiquitous occurrence. In rural areas, the pollution of water bodies with heavy metals and agrochemicals poses a problem to surface water quality. Among problematic compounds, heavy metals (copper) and pesticides are frequently found in water bodies. To establish duckweed as a potential plant for phytoremediation, enzymatic and antioxidative stress responses of Lemna minor during exposure to copper and a chloroacetamide herbicide were investigated in laboratory studies. The present study aimed at evaluating growth and the antioxidative and glutathione-dependent enzyme activity of Lemna plants and its performance in a scenario for phytoremediation of copper and a chloroacetamide herbicide. Lemna minor was grown in Steinberg medium under controlled conditions. Plants were treated with CuSO4 (ion conc. 50 and 100 μg/L) and pethoxamide (1.25 and 2.5 μg/L). Measurements following published methods focused on plant growth, oxidative stress, and basic detoxification enzymes. Duckweed proved to survive treatment with the respective concentrations of both pollutants very well. Its growth was inhibited scarcely, and no visible symptoms occurred. On the cellular basis, accumulation of O2(-) and H2O2 were detected, as well as stress reactions of antioxidative enzymes. Duckweed detoxification potential for organic pollutants was high and increased significantly with incubation. Pethoxamide was found to be conjugated with glutathione. Copper was accumulated in the fronds at high levels, and transient oxidative defense reactions were triggered. This work confirms the significance of L. minor for the removal of copper from water and the conjugation of the selective herbicide pethoxamide. Both organic and inorganic xenobiotics induced different trends of enzymatic and antioxidative stress response. The strong increase of stress

  7. Low cytotoxicity of inorganic nanotubes and fullerene-like nanostructures in human bronchial epithelial cells: relation to inflammatory gene induction and antioxidant response.

    PubMed

    Pardo, Michal; Shuster-Meiseles, Timor; Levin-Zaidman, Smadar; Rudich, Assaf; Rudich, Yinon

    2014-03-18

    The cytotoxicity of tungsten disulfide nano tubes (INT-WS2) and inorganic fullerene-like molybdenum disulfide (IF-MoS2) nanoparticles (NPs) used in industrial and medical applications was evaluated in comparison to standard environmental particulate matter. The IF-MoS2 and INT-WS2 reside in vesicles/inclusion bodies, suggestive of endocytic vesicles. In cells representing the respiratory, immune and metabolic systems, both IF-MoS2 and INT-WS2 NPs remained nontoxic compared to equivalent concentrations (up to 100 μg/mL in the medium) of silica dioxide (SiO2), diesel engine-derived and carbon black NPs, which induced cell death. Associating with this biocompatibility of IF-MoS2\\INT-WS2, we demonstrate in nontransformed human bronchial cells (NL-20) relative low induction of the pro-inflammatory cytokines IL-1β, IL-6, IL-8, and TNF-α. Moreover, IF-MoS2 and INT-WS2 activated antioxidant response as measured by the antioxidant response element (ARE) using a luciferase reporter, and induced Nrf2-mediated Phase II detoxification genes. Collectively, our findings suggest that the lower cytotoxicity of IF-MoS2 and INT-WS2 NPs does not reflect general biological inertness. Rather, compared to other NP's, it likely results from decreased pro-inflammatory activation, but a comparable significant capacity to induce protective antioxidant/detoxification defense mechanisms.

  8. Role of Estrogen Response Element in the Human Prolactin Gene: Transcriptional Response and Timing

    PubMed Central

    McNamara, Anne V.; Adamson, Antony D.; Dunham, Lee S. S.; Semprini, Sabrina; Spiller, David G.; McNeilly, Alan S.; Mullins, John J.

    2016-01-01

    The use of bacterial artificial chromosome (BAC) reporter constructs in molecular physiology enables the inclusion of large sections of flanking DNA, likely to contain regulatory elements and enhancers regions that contribute to the transcriptional output of a gene. Using BAC recombineering, we have manipulated a 160-kb human prolactin luciferase (hPRL-Luc) BAC construct and mutated the previously defined proximal estrogen response element (ERE) located −1189 bp relative to the transcription start site, to assess its involvement in the estrogen responsiveness of the entire hPRL locus. We found that GH3 cell lines stably expressing Luc under control of the ERE-mutated hPRL promoter (ERE-Mut) displayed a dramatically reduced transcriptional response to 17β-estradiol (E2) treatment compared with cells expressing Luc from the wild-type (WT) ERE hPRL-Luc promoter (ERE-WT). The −1189 ERE controls not only the response to E2 treatment but also the acute transcriptional response to TNFα, which was abolished in ERE-Mut cells. ERE-WT cells displayed a biphasic transcriptional response after TNFα treatment, the acute phase of which was blocked after treatment with the estrogen receptor antagonist 4-hydroxy-tamoxifen. Unexpectedly, we show the oscillatory characteristics of hPRL promoter activity in individual living cells were unaffected by disruption of this crucial response element, real-time bioluminescence imaging showed that transcription cycles were maintained, with similar cycle lengths, in ERE-WT and ERE-Mut cells. These data suggest the −1189 ERE is the dominant response element involved in the hPRL transcriptional response to both E2 and TNFα and, crucially, that cycles of hPRL promoter activity are independent of estrogen receptor binding. PMID:26691151

  9. Relationships among alcoholic liver disease, antioxidants, and antioxidant enzymes.

    PubMed

    Han, Kyu-Ho; Hashimoto, Naoto; Fukushima, Michihiro

    2016-01-01

    Excessive consumption of alcoholic beverages is a serious cause of liver disease worldwide. The metabolism of ethanol generates reactive oxygen species, which play a significant role in the deterioration of alcoholic liver disease (ALD). Antioxidant phytochemicals, such as polyphenols, regulate the expression of ALD-associated proteins and peptides, namely, catalase, superoxide dismutase, glutathione, glutathione peroxidase, and glutathione reductase. These plant antioxidants have electrophilic activity and may induce antioxidant enzymes via the Kelch-like ECH-associated protein 1-NF-E2-related factor-2 pathway and antioxidant responsive elements. Furthermore, these antioxidants are reported to alleviate cell injury caused by oxidants or inflammatory cytokines. These phenomena are likely induced via the regulation of mitogen-activating protein kinase (MAPK) pathways by plant antioxidants, similar to preconditioning in ischemia-reperfusion models. Although the relationship between plant antioxidants and ALD has not been adequately investigated, plant antioxidants may be preventive for ALD because of their electrophilic and regulatory activities in the MAPK pathway. PMID:26755859

  10. Relationships among alcoholic liver disease, antioxidants, and antioxidant enzymes

    PubMed Central

    Han, Kyu-Ho; Hashimoto, Naoto; Fukushima, Michihiro

    2016-01-01

    Excessive consumption of alcoholic beverages is a serious cause of liver disease worldwide. The metabolism of ethanol generates reactive oxygen species, which play a significant role in the deterioration of alcoholic liver disease (ALD). Antioxidant phytochemicals, such as polyphenols, regulate the expression of ALD-associated proteins and peptides, namely, catalase, superoxide dismutase, glutathione, glutathione peroxidase, and glutathione reductase. These plant antioxidants have electrophilic activity and may induce antioxidant enzymes via the Kelch-like ECH-associated protein 1-NF-E2-related factor-2 pathway and antioxidant responsive elements. Furthermore, these antioxidants are reported to alleviate cell injury caused by oxidants or inflammatory cytokines. These phenomena are likely induced via the regulation of mitogen-activating protein kinase (MAPK) pathways by plant antioxidants, similar to preconditioning in ischemia-reperfusion models. Although the relationship between plant antioxidants and ALD has not been adequately investigated, plant antioxidants may be preventive for ALD because of their electrophilic and regulatory activities in the MAPK pathway. PMID:26755859

  11. Developmental stage is an important factor that determines the antioxidant responses of young and old grapevine leaves under UV irradiation in a green-house.

    PubMed

    Majer, Petra; Hideg, Eva

    2012-01-01

    The impact of UV irradiation was studied on photosynthesis, photosystem II photochemical yields and antioxidant responses using green-house grown grapevine (Vitis vinifera L. cv. Chardonnay) leaves. Supplemental UV irradiation (280-400 nm) was centred in the UV-B region, and corresponded to 8.95 kJ m⁻² d⁻¹ global (280-400 nm) or 8.04 kJ m⁻² d⁻¹ UV-B (280-315 nm) biologically effective dose. UV irradiation was applied daily and its effects were evaluated after 4-days. Younger (1-3 weeks-old) leaves (YL) and older (4-6 weeks-old) leaves (OL) were affected differently, UV irradiation decreased their photochemical yields to 78% and 56%, respectively. Unlike OL, YL responded by an increase in UV-B absorbing pigment, anthocyanin and total phenolics contents. UV irradiation increased total antioxidant capacities in YL but not in OL. YL were also different in their ability to increase specific hydroxyl radical and singlet oxygen neutralizing capacities in response to the supplemental UV irradiation, which is reported here for the first time. Our results suggest that the ability of maintaining photosynthesis under supplemental UV is not necessarily determined by base levels of antioxidants but rather by their inducibilities in response to the irradiation and emphasise the importance of comparing leaves of the same age in UV studies. Correlations between various antioxidant capacities, pigment contents and photosynthesis parameters were also examined. However, no single element of the defence system can be picked up as decisive factor of sensitivity to UV.

  12. Decreased Total Antioxidant Activity in Major Depressive Disorder Patients Non-Responsive to Antidepressant Treatment

    PubMed Central

    Baek, Song-Eun; Lee, Gyoung-Ja; Rhee, Chang-Kyu; Rho, Dae-Young; Kim, Do-Hoon; Huh, Sun

    2016-01-01

    Objective This study aimed to evaluate the total antioxidant activity (TAA) in patients with major depressive disorder (MDD) and the effect of antidepressants on TAA using a novel potentiometric method. Methods Twenty-eight patients with MDD and thirty-one healthy controls were enrolled in this study. The control group comprised 31 healthy individuals matched for gender, drinking and smoking status. We assessed symptoms of depression using the Hamilton Depression Rating Scale (HAMD) and the Beck Depression Inventory (BDI). We measured TAA using potentiometry. All measurements were made at baseline and four and eight weeks later. Results There was a significant negative correlation between BDI scores and TAA. TAA was significantly lower in the MDD group than in controls. When the MDD group was subdivided into those who showed clinical response to antidepressant therapy (response group) and those who did not (non-response group), only the non-response group showed lower TAA, while the response group showed no significant difference to controls at baseline. After eight weeks of antidepressant treatment, TAA in both the response and non-response groups was similar, and there was no significant difference among the three groups. Conclusion These results suggest that the response to antidepressant treatment in MDD patients might be predicted by measuring TAA. PMID:27081384

  13. Differential responses of the antioxidant system of ametryn and clomazone tolerant bacteria.

    PubMed

    Peters, Leila Priscila; Carvalho, Giselle; Martins, Paula Fabiane; Dourado, Manuella Nóbrega; Vilhena, Milca Bartz; Pileggi, Marcos; Azevedo, Ricardo Antunes

    2014-01-01

    The herbicides ametryn and clomazone are widely used in sugarcane cultivation, and following microbial degradation are considered as soil and water contaminants. The exposure of microorganisms to pesticides can result in oxidative damage due to an increase in the production of reactive oxygen species (ROS). This study investigated the response of the antioxidant systems of two bacterial strains tolerant to the herbicides ametryn and clomazone. Bacteria were isolated from soil with a long history of ametryn and clomazone application. Comparative analyses based on 16S rRNA gene sequences revealed that strain CC07 is phylogenetically related to Pseudomonas aeruginosa and strain 4C07 to P. fulva. The two bacterial strains were grown for 14 h in the presence of separate and combined herbicides. Lipid peroxidation, reduced glutathione content (GSH) and antioxidant enzymes activities were evaluated. The overall results indicated that strain 4C07 formed an efficient mechanism to maintain the cellular redox balance by producing reactive oxygen species (ROS) and subsequently scavenging ROS in the presence of the herbicides. The growth of bacterium strain 4C07 was inhibited in the presence of clomazone alone, or in combination with ametryn, but increased glutathione reductase (GR) and glutathione S-transferase (GST) activities, and a higher GSH concentration were detected. Meanwhile, reduced superoxide dismutase (SOD), catalase (CAT) and GST activities and a lower concentration of GSH were detected in the bacterium strain CC07, which was able to achieve better growth in the presence of the herbicides. The results suggest that the two bacterial strains tolerate the ametryn and clomazone herbicides with distinctly different responses of the antioxidant systems.

  14. Differential Responses of the Antioxidant System of Ametryn and Clomazone Tolerant Bacteria

    PubMed Central

    Peters, Leila Priscila; Carvalho, Giselle; Martins, Paula Fabiane; Dourado, Manuella Nóbrega; Vilhena, Milca Bartz; Pileggi, Marcos; Azevedo, Ricardo Antunes

    2014-01-01

    The herbicides ametryn and clomazone are widely used in sugarcane cultivation, and following microbial degradation are considered as soil and water contaminants. The exposure of microorganisms to pesticides can result in oxidative damage due to an increase in the production of reactive oxygen species (ROS). This study investigated the response of the antioxidant systems of two bacterial strains tolerant to the herbicides ametryn and clomazone. Bacteria were isolated from soil with a long history of ametryn and clomazone application. Comparative analyses based on 16S rRNA gene sequences revealed that strain CC07 is phylogenetically related to Pseudomonas aeruginosa and strain 4C07 to P. fulva. The two bacterial strains were grown for 14 h in the presence of separate and combined herbicides. Lipid peroxidation, reduced glutathione content (GSH) and antioxidant enzymes activities were evaluated. The overall results indicated that strain 4C07 formed an efficient mechanism to maintain the cellular redox balance by producing reactive oxygen species (ROS) and subsequently scavenging ROS in the presence of the herbicides. The growth of bacterium strain 4C07 was inhibited in the presence of clomazone alone, or in combination with ametryn, but increased glutathione reductase (GR) and glutathione S-transferase (GST) activities, and a higher GSH concentration were detected. Meanwhile, reduced superoxide dismutase (SOD), catalase (CAT) and GST activities and a lower concentration of GSH were detected in the bacterium strain CC07, which was able to achieve better growth in the presence of the herbicides. The results suggest that the two bacterial strains tolerate the ametryn and clomazone herbicides with distinctly different responses of the antioxidant systems. PMID:25380132

  15. Thioureas as reporting elements for metal-responsive fluorescent chemosensors.

    PubMed

    Vonlanthen, Mireille; Finney, Nathaniel S

    2013-04-19

    Proof that sulfur is a viable reporting element for the development of fluorescent chemosensors for metal ions is presented. To date, the majority of metal-responsive fluorescent chemosensors have relied on metal-nitrogen coordination to provide a fluorescence response, most commonly by suppressing photoinduced electron transfer (PET) quenching. While chemosensors with direct application to biology, medicine, and analytical chemistry have been so developed, reliance on the coordination chemistry of nitrogen remains a practical and conceptual limitation. Building on the fact that thioureas can quench fluorescence emission by PET, it is shown that the quenched emission of thiourea-appended naphthalimides can be restored by metal binding and that metal affinity and selectivity can be controlled through structural modification of the thiourea substituents. Further, such chemosensors can function in aqueous media and, unlike nitrogen-based chemosensors, are unresponsive to increases in [H(+)]. Given that the coordination properties of sulfur are distinct from those of nitrogen, this work lays the foundation for the development of a new class of interesting and useful metal-responsive fluorescent probes. PMID:23470031

  16. Antioxidant-enriched enteral nutrition and immuno-inflammatory response after major gastrointestinal tract surgery.

    PubMed

    van Stijn, Mireille F M; Boelens, Petra G; Richir, Milan C; Ligthart-Melis, Gerdien C; Twisk, Jos W R; Diks, Jeroen; Houdijk, Alexander P J; van Leeuwen, Paul A M

    2010-02-01

    Major surgery induces an immuno-inflammatory response accompanied by oxidative stress that may impair cellular function and delay recovery. The objective of the study was to investigate the effect of an enteral supplement, containing glutamine and antioxidants, on circulating levels of immuno-inflammatory markers after major gastrointestinal tract surgery. Patients (n 21) undergoing major gastrointestinal tract surgery were randomised in a single-centre, open-label study. The effects on circulating levels of immuno-inflammatory markers were determined on the day before surgery and on days 1, 3, 5 and 7 after surgery. Major gastrointestinal surgery increased IL-6, TNF receptor 55/60 (TNF-R55) and C-reactive protein (CRP). Surgery reduced human leucocyte antigen-DR (HLA-DR) expression on monocytes. CRP decrease was more pronounced in the first 7 d in the treatment group compared with the control group. In the treatment group, from the moment Module AOX was administered on day 1 after surgery, TNF receptor 75/80 (TNF-R75) level decreased until the third post-operative day and then stabilised, whereas in the control group the TNF-R75 level continued to increase. The results of the present pilot study suggest that enteral nutrition enriched with glutamine and antioxidants possibly moderates the immuno-inflammatory response (CRP, TNF-R75) after surgery.

  17. Antioxidant enzymes activities of Burkholderia spp. strains-oxidative responses to Ni toxicity.

    PubMed

    Dourado, M N; Franco, M R; Peters, L P; Martins, P F; Souza, L A; Piotto, F A; Azevedo, R A

    2015-12-01

    Increased agriculture production associated with intense application of herbicides, pesticides, and fungicides leads to soil contamination worldwide. Nickel (Ni), due to its high mobility in soils and groundwater, constitutes one of the greatest problems in terms of environmental pollution. Metals, including Ni, in high concentrations are toxic to cells by imposing a condition of oxidative stress due to the induction of reactive oxygen species (ROS), which damage lipids, proteins, and DNA. This study aimed to characterize the Ni antioxidant response of two tolerant Burkholderia strains (one isolated from noncontaminated soil, SNMS32, and the other from contaminated soil, SCMS54), by measuring superoxide dismutase (SOD), catalase (CAT), glutathione reductase (GR), and glutathione S-transferase (GST) activities. Ni accumulation and bacterial growth in the presence of the metal were also analyzed. The results showed that both strains exhibited different trends of Ni accumulation and distinct antioxidant enzymes responses. The strain from contaminated soil (SCMS54) exhibited a higher Ni biosorption and exhibited an increase in SOD and GST activities after 5 and 12 h of Ni exposure. The analysis of SOD, CAT, and GR by nondenaturing PAGE revealed the appearance of an extra isoenzyme in strain SCMS54 for each enzyme. The results suggest that the strain SCMS54 isolated from contaminated soil present more plasticity with potential to be used in soil and water bioremediation.

  18. Variations in oxygen concentration cause differential antioxidant response and expression of related genes in Beauveria bassiana.

    PubMed

    Garza-López, Paul Misael; Suárez-Vergel, Gerardo; Hamdan-Partida, Aida; Loera, Octavio

    2015-04-01

    The entomopathogenic fungus Beauveria bassiana is widely used in pest biocontrol strategies. We evaluated both the antioxidant response mediated by compatible solutes, trehalose or mannitol, and the expression of related genes using oxygen pulses at three oxygen concentrations in solid state culture (SSC): normal atmosphere (21% O2), low oxygen (16% O2) and enriched oxygen (26% O2). Trehalose concentration decreased 75% after atmospheric modifications in the cultures, whereas mannitol synthesis was three-fold higher under the 16% O2 pulses relative to normal atmosphere (100 and 30 μg mannitol mg(-1) biomass, respectively). Confirming this result, expression of the mpd gene, coding for mannitol-1-P dehydrogenase (MPD), increased up to 1.4 times after O2 pulses. The expression of the bbrgs1 gene, encoding a regulatory G protein related to conidiation, was analysed to explain previously reported differences in conidial production. Surprisingly, expression of bbrgs1 decreased after atmospheric modification. Finally, principal component analysis (PCA) indicated that 83.39% of the variability in the data could be explained by two components. This analysis corroborated the positive correlation between mannitol concentration and mpd gene expression, as well as the negative correlation between conidial production and bbrgs1 gene expression. This study contributes to understanding of antioxidant and molecular response of B. bassiana induced under oxidant conditions.

  19. Antioxidant enzymes activities of Burkholderia spp. strains-oxidative responses to Ni toxicity.

    PubMed

    Dourado, M N; Franco, M R; Peters, L P; Martins, P F; Souza, L A; Piotto, F A; Azevedo, R A

    2015-12-01

    Increased agriculture production associated with intense application of herbicides, pesticides, and fungicides leads to soil contamination worldwide. Nickel (Ni), due to its high mobility in soils and groundwater, constitutes one of the greatest problems in terms of environmental pollution. Metals, including Ni, in high concentrations are toxic to cells by imposing a condition of oxidative stress due to the induction of reactive oxygen species (ROS), which damage lipids, proteins, and DNA. This study aimed to characterize the Ni antioxidant response of two tolerant Burkholderia strains (one isolated from noncontaminated soil, SNMS32, and the other from contaminated soil, SCMS54), by measuring superoxide dismutase (SOD), catalase (CAT), glutathione reductase (GR), and glutathione S-transferase (GST) activities. Ni accumulation and bacterial growth in the presence of the metal were also analyzed. The results showed that both strains exhibited different trends of Ni accumulation and distinct antioxidant enzymes responses. The strain from contaminated soil (SCMS54) exhibited a higher Ni biosorption and exhibited an increase in SOD and GST activities after 5 and 12 h of Ni exposure. The analysis of SOD, CAT, and GR by nondenaturing PAGE revealed the appearance of an extra isoenzyme in strain SCMS54 for each enzyme. The results suggest that the strain SCMS54 isolated from contaminated soil present more plasticity with potential to be used in soil and water bioremediation. PMID:26289332

  20. CACUL1/CAC1 Regulates the Antioxidant Response by Stabilizing Nrf2

    PubMed Central

    Kigoshi, Yu; Fukuda, Tomomi; Endo, Tomoyuki; Hayasaka, Nami; Iemura, Shun-ichiro; Natsume, Toru; Tsuruta, Fuminori; Chiba, Tomoki

    2015-01-01

    Nrf2 is the pre-dominant transcription activator responsible for coordinated up-regulation of ARE-driven antioxidant and detoxification genes. The activity of Nrf2 is tightly regulated at basal levels through its ubiquitination by Cul3-Keap1 and consequential degradation. Upon exposure to stress, the Cul3-Keap1 ligase is inhibited, leading to Nrf2 stabilization and activation. Here we describe CACUL1/CAC1 as a positive regulator of the Nrf2 pathway. We found that CACUL1 is up-regulated by Nrf2-activating oxidative stresses in cells and in mice. The association of CACUL1 with the Cul3-Keap1 complex led to a decrease in Nrf2 ubiquitination levels at non-stressed as well as stressed conditions, and sensitized cells for higher Nrf2 activation. Furthermore, CACUL1 knock-down led to a decrease in Nrf2 activity and cell viability under stress. Our results show that CACUL1 is a regulator of Nrf2 ubiquitination, adding another regulatory layer to the Nrf2 antioxidant stress response. PMID:26238671

  1. Antioxidative responses in zebrafish liver exposed to sublethal doses Aphanizomenon flos-aquae DC-1 aphantoxins.

    PubMed

    Zhang, De Lu; Liu, Si Yi; Zhang, Jing; Hu, Chun Xiang; Li, Dun Hai; Liu, Yong Ding

    2015-03-01

    Aphanizomenon flos-aquae secretes paralytic shellfish poisons (PSPs), termed aphantoxins, and endangers environmental and human health via eutrophication of water worldwide. Although the molecular mechanism of neuronal PSP toxicity has been well studied, several issues remain unresolved, notably the in vivo hepatic antioxidative responses to this neurotoxin. Aphantoxins extracted from a natural isolate of A. flos-aquae DC-1 were resolved by high performance liquid chromatography. The primary components were gonyautoxins 1 and 5 and neosaxitoxin. Zebrafish (Danio rerio) were treated intraperitoneally with either 5.3 or 7.61 (low and high doses, respectively) μg saxitoxin (STX) equivalents (eq)/kg of A. flos-aquae DC-1 aphantoxins. Antioxidative responses in zebrafish liver were examined at different timepoints 1-24h post-exposure. Aphantoxin administration significantly enhanced hepatic malondialdehyde (MDA) content 1-12h post-exposure, indicative of oxidative stress and lipid peroxidation. By contrast, levels of reduced glutathione (GSH) in zebrafish liver declined significantly after 3-24h exposure, suggesting that GSH participates in MDA metabolism. A significant upregulation of the activities of superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GPx) was observed, suggesting that aphantoxins induce lipid peroxidation in zebrafish liver and are likely to be hepatotoxic. Hepatic levels of MDA and GSH, and of the three enzymes (SOD, CAT, and GPx), therefore provide potential biomarkers for studying environmental exposure to aphantoxins/PSPs from cyanobacterial blooms. PMID:25544652

  2. Neurotoxic effect of triazophos on goldfish (Carassius auratus) and tissue specific antioxidant responses.

    PubMed

    Liu, Lei; Zhu, Bin; Gong, Yu-Xin; Liu, Guang-Lu; Wang, Gao-Xue

    2015-06-01

    Due to the high chemical and photochemical stability, an organophosphorus pesticide triazophos might enter aquatic ecosystems and impose negative effect on aquatic organisms. In order to investigate short-term toxicity of triazophos on goldfish (Carassius auratus), antioxidant response in brain, spleen, kidney and liver was tested in this study. As a confirmation, the impact of triazophos on acetyl cholinesterase (AChE) activity was found a reduction in all studied tissues, especially in brain. In addition, 0.1 and 0.5 mg L(-1) triazophos induced MDA level increased, while glutathione content (GSH), superoxide dismutase (SOD), catalase (CAT) and lactate dehydrogenase (LDH) activities decreased. Of note, more prominent oxidative stress was provoked in kidney and liver, but weaker in brain and spleen. These results revealed that triazophos could cause a generalized oxidative stress and tissue specific antioxidant response in goldfish. Furthermore, neuroendocrine-growth-related gene expression (growth hormone (GH), luteinizing hormone (LH) and peptide YY) in brain was also changed by exposed to triazophos during 4 and 7d exposure periods. Linked with the above results, the present study pointed out that triazophos might induce a neurotoxic effect and oxidative damage in goldfish, and the goldfish brain should be a critical target for triazophos-induced damage.

  3. Variations in oxygen concentration cause differential antioxidant response and expression of related genes in Beauveria bassiana.

    PubMed

    Garza-López, Paul Misael; Suárez-Vergel, Gerardo; Hamdan-Partida, Aida; Loera, Octavio

    2015-04-01

    The entomopathogenic fungus Beauveria bassiana is widely used in pest biocontrol strategies. We evaluated both the antioxidant response mediated by compatible solutes, trehalose or mannitol, and the expression of related genes using oxygen pulses at three oxygen concentrations in solid state culture (SSC): normal atmosphere (21% O2), low oxygen (16% O2) and enriched oxygen (26% O2). Trehalose concentration decreased 75% after atmospheric modifications in the cultures, whereas mannitol synthesis was three-fold higher under the 16% O2 pulses relative to normal atmosphere (100 and 30 μg mannitol mg(-1) biomass, respectively). Confirming this result, expression of the mpd gene, coding for mannitol-1-P dehydrogenase (MPD), increased up to 1.4 times after O2 pulses. The expression of the bbrgs1 gene, encoding a regulatory G protein related to conidiation, was analysed to explain previously reported differences in conidial production. Surprisingly, expression of bbrgs1 decreased after atmospheric modification. Finally, principal component analysis (PCA) indicated that 83.39% of the variability in the data could be explained by two components. This analysis corroborated the positive correlation between mannitol concentration and mpd gene expression, as well as the negative correlation between conidial production and bbrgs1 gene expression. This study contributes to understanding of antioxidant and molecular response of B. bassiana induced under oxidant conditions. PMID:25813512

  4. Antioxidant response and carboxylate metabolism in Brassica rapa exposed to different external Zn, Ca, and Mg supply.

    PubMed

    Blasco, Begoña; Graham, Neil S; Broadley, Martin R

    2015-03-15

    Zinc (Zn), calcium (Ca), and magnesium (Mg) malnutrition are common deficiencies in many developed and developing countries, resulting in a widespread health problem. Biofortification of food crops is an agricultural strategy that can be used to increase the levels of these elements in the edible portions of crops. Deficiency or toxicity of these cations in soils reduces plant growth, crop yield, and the quality of plant foodstuff. The aim of this study was to investigate the effect of external Zn, Ca, and Mg supply on accumulation and distribution of this elements as well as antioxidant response and organic acid composition of Brassica rapa ssp. trilocularis line R-o-18. Plants were grown at low Zn (0.05 μM Zn) and high Zn (500 μM Zn), low Ca (0.4 mM) and high Ca (40 mM), and low Mg (0.2 mM), and high Mg (20 mM) to simulate deficiency and toxicity conditions. Larger shoot biomass reductions were observed under high Zn, Ca and Mg treatments, and superoxide dismutase (SOD), ascorbate peroxidase (APX), H2O2, malondialdehyde (MDA), and total ascorbate (AA) showed a marked increase in these treatments. Therefore, Brassica plants might be more sensitive to excess of these elements in the nutrient solution. The translocation factor (TF) and distribution coefficient (DC) values of Zn, Ca, and Mg indicated higher translocation and accumulation in deficient conditions. High biosynthesis and citrate content in Brassica plants may be associated mainly with a high-nutrient solution extraction ability of these plants. These results provide background data, which will be used to characterize TILLING mutants to study the effects of mutations in genes involved in regulating Zn, Ca, and Mg distribution and accumulation in plants. PMID:25544655

  5. Antioxidant response and carboxylate metabolism in Brassica rapa exposed to different external Zn, Ca, and Mg supply.

    PubMed

    Blasco, Begoña; Graham, Neil S; Broadley, Martin R

    2015-03-15

    Zinc (Zn), calcium (Ca), and magnesium (Mg) malnutrition are common deficiencies in many developed and developing countries, resulting in a widespread health problem. Biofortification of food crops is an agricultural strategy that can be used to increase the levels of these elements in the edible portions of crops. Deficiency or toxicity of these cations in soils reduces plant growth, crop yield, and the quality of plant foodstuff. The aim of this study was to investigate the effect of external Zn, Ca, and Mg supply on accumulation and distribution of this elements as well as antioxidant response and organic acid composition of Brassica rapa ssp. trilocularis line R-o-18. Plants were grown at low Zn (0.05 μM Zn) and high Zn (500 μM Zn), low Ca (0.4 mM) and high Ca (40 mM), and low Mg (0.2 mM), and high Mg (20 mM) to simulate deficiency and toxicity conditions. Larger shoot biomass reductions were observed under high Zn, Ca and Mg treatments, and superoxide dismutase (SOD), ascorbate peroxidase (APX), H2O2, malondialdehyde (MDA), and total ascorbate (AA) showed a marked increase in these treatments. Therefore, Brassica plants might be more sensitive to excess of these elements in the nutrient solution. The translocation factor (TF) and distribution coefficient (DC) values of Zn, Ca, and Mg indicated higher translocation and accumulation in deficient conditions. High biosynthesis and citrate content in Brassica plants may be associated mainly with a high-nutrient solution extraction ability of these plants. These results provide background data, which will be used to characterize TILLING mutants to study the effects of mutations in genes involved in regulating Zn, Ca, and Mg distribution and accumulation in plants.

  6. Hormetic response triggers multifaceted anti-oxidant strategies in immature king penguins (Aptenodytes patagonicus).

    PubMed

    Rey, Benjamin; Dégletagne, Cyril; Bodennec, Jacques; Monternier, Pierre-Axel; Mortz, Mathieu; Roussel, Damien; Romestaing, Caroline; Rouanet, Jean-Louis; Tornos, Jeremy; Duchamp, Claude

    2016-08-01

    Repeated deep dives are highly pro-oxidative events for air-breathing aquatic foragers such as penguins. At fledging, the transition from a strictly terrestrial to a marine lifestyle may therefore trigger a complex set of anti-oxidant responses to prevent chronic oxidative stress in immature penguins but these processes are still undefined. By combining in vivo and in vitro approaches with transcriptome analysis, we investigated the adaptive responses of sea-acclimatized (SA) immature king penguins (Aptenodytes patagonicus) compared with pre-fledging never-immersed (NI) birds. In vivo, experimental immersion into cold water stimulated a higher thermogenic response in SA penguins than in NI birds, but both groups exhibited hypothermia, a condition favouring oxidative stress. In vitro, the pectoralis muscles of SA birds displayed increased oxidative capacity and mitochondrial protein abundance but unchanged reactive oxygen species (ROS) generation per g tissue because ROS production per mitochondria was reduced. The genes encoding oxidant-generating proteins were down-regulated in SA birds while mRNA abundance and activity of the main antioxidant enzymes were up-regulated. Genes encoding proteins involved in repair mechanisms of oxidized DNA or proteins and in degradation processes were also up-regulated in SA birds. Sea life also increased the degree of fatty acid unsaturation in muscle mitochondrial membranes resulting in higher intrinsic susceptibility to ROS. Oxidative damages to protein or DNA were reduced in SA birds. Repeated experimental immersions of NI penguins in cold-water partially mimicked the effects of acclimatization to marine life, modified the expression of fewer genes related to oxidative stress but in a similar way as in SA birds and increased oxidative damages to DNA. It is concluded that the multifaceted plasticity observed after marine life may be crucial to maintain redox homeostasis in active tissues subjected to high pro-oxidative pressure

  7. Hormetic response triggers multifaceted anti-oxidant strategies in immature king penguins (Aptenodytes patagonicus).

    PubMed

    Rey, Benjamin; Dégletagne, Cyril; Bodennec, Jacques; Monternier, Pierre-Axel; Mortz, Mathieu; Roussel, Damien; Romestaing, Caroline; Rouanet, Jean-Louis; Tornos, Jeremy; Duchamp, Claude

    2016-08-01

    Repeated deep dives are highly pro-oxidative events for air-breathing aquatic foragers such as penguins. At fledging, the transition from a strictly terrestrial to a marine lifestyle may therefore trigger a complex set of anti-oxidant responses to prevent chronic oxidative stress in immature penguins but these processes are still undefined. By combining in vivo and in vitro approaches with transcriptome analysis, we investigated the adaptive responses of sea-acclimatized (SA) immature king penguins (Aptenodytes patagonicus) compared with pre-fledging never-immersed (NI) birds. In vivo, experimental immersion into cold water stimulated a higher thermogenic response in SA penguins than in NI birds, but both groups exhibited hypothermia, a condition favouring oxidative stress. In vitro, the pectoralis muscles of SA birds displayed increased oxidative capacity and mitochondrial protein abundance but unchanged reactive oxygen species (ROS) generation per g tissue because ROS production per mitochondria was reduced. The genes encoding oxidant-generating proteins were down-regulated in SA birds while mRNA abundance and activity of the main antioxidant enzymes were up-regulated. Genes encoding proteins involved in repair mechanisms of oxidized DNA or proteins and in degradation processes were also up-regulated in SA birds. Sea life also increased the degree of fatty acid unsaturation in muscle mitochondrial membranes resulting in higher intrinsic susceptibility to ROS. Oxidative damages to protein or DNA were reduced in SA birds. Repeated experimental immersions of NI penguins in cold-water partially mimicked the effects of acclimatization to marine life, modified the expression of fewer genes related to oxidative stress but in a similar way as in SA birds and increased oxidative damages to DNA. It is concluded that the multifaceted plasticity observed after marine life may be crucial to maintain redox homeostasis in active tissues subjected to high pro-oxidative pressure

  8. Proteasome inhibition induces both antioxidant and hb f responses in sickle cell disease via the nrf2 pathway.

    PubMed

    Pullarkat, Vinod; Meng, Zhuo; Tahara, Stanley M; Johnson, Cage S; Kalra, Vijay K

    2014-01-01

    Oxidant stress is implicated in the manifestations of sickle cell disease including hemolysis and vascular occlusion. Strategies to induce antioxidant response as well as Hb F (α2γ2) have the potential to ameliorate the severity of sickle cell disease. Nuclear factor (erythroid-derived 2)-like 2 (NFE2L2 or Nrf2) is a transcription factor that regulates antioxidant enzymes as well as γ-globin transcription. The Nrf2 in the cytoplasm is bound to its adapter protein Keap-1 that targets Nrf2 for proteasomal degradation, thereby preventing its nuclear translocation. We examined whether inhibiting the 26S proteasome using the clinically applicable proteasome inhibitors bortezomib and MLN 9708 would promote nuclear translocation of Nrf2, and thereby induce an antioxidant response and as well as Hb F in sickle cell disease. Proteasome inhibitors induced reactive oxygen species (ROS) and thereby increased Nrf2-dependent antioxidant enzyme transcripts, elevated cellular glutathione (GSH) levels and γ-globin transcripts as well as Hb F levels in the K562 cell line and also in erythroid burst forming units (BFU-E) generated from peripheral blood mononuclear cells of sickle cell disease patients. These responses were abolished by siRNA-mediated knockdown of Nrf2. Proteasome inhibitors, especially newer oral agents such as MLN9708 have the potential to be readily translated to clinical trials in sickle cell disease with the dual end points of antioxidant response and Hb F induction.

  9. Morinda citrifolia leaf enhanced performance by improving angiogenesis, mitochondrial biogenesis, antioxidant, anti-inflammatory & stress responses.

    PubMed

    Mohamad Shalan, Nor Aijratul Asikin; Mustapha, Noordin M; Mohamed, Suhaila

    2016-12-01

    Morinda citrifolia fruit, (noni), enhanced performances in athletes and post-menopausal women in clinical studies. This report shows the edible noni leaves water extract enhances performance in a weight-loaded swimming animal model better than the fruit or standardized green tea extract. The 4weeks study showed the extract (containing scopoletin and epicatechin) progressively prolonged the time to exhaustion by threefold longer than the control, fruit or tea extract. The extract improved (i) the mammalian antioxidant responses (MDA, GSH and SOD2 levels), (ii) tissue nutrient (glucose) and metabolite (lactate) management, (iii) stress hormone (cortisol) regulation; (iv) neurotransmitter (dopamine, noradrenaline, serotonin) expressions, transporter or receptor levels, (v) anti-inflammatory (IL4 & IL10) responses; (v) skeletal muscle angiogenesis (VEGFA) and (v) energy and mitochondrial biogenesis (via PGC, UCP3, NRF2, AMPK, MAPK1, and CAMK4). The ergogenic extract helped delay fatigue by enhancing energy production, regulation and efficiency, which suggests benefits for physical activities and disease recovery.

  10. Antioxidant Potential and In Situ Analysis of Major and Trace Element Determination of Ood-saleeb, a Known Unani Herbal Medicine by ICP-MS.

    PubMed

    Raish, Mohammad; Ahmad, Ajaz; Alkharfy, Khalid M; Al-Jenoobi, Fahad I; Al-Mohizea, Abdullah M; Mohsin, Kazi; Ahamad, Syed Rizwan; Ali, Naushad; Shakeel, Faiyaz

    2016-08-01

    The intention of the present research work was to investigate the antioxidant activity and trace element analysis of Ood-saleeb, a known herbal medicine. Preliminary screening of phytochemicals showed that the extract of Ood-saleeb had flavonoids and phenolics. The significant activities in all antioxidant assays were observed in the extract of Ood-saleeb in comparison with the standard antioxidant with respect to dose of Ood-saleeb. Incredible activities to scavenge reactive oxygen species were also observed by the extract of Ood-saleeb. The IC50 values of all factors were determined using ascorbic acid as a standard. The inductive coupled plasma-mass spectroscopy (ICP-MS) was employed for the estimation of trace elements in Ood-saleeb extract. The concentrations of up to 18 elements were detected successfully. Silicon was found in high concentration (85.3 μg/g) while lithium was in low concentration (3 ng/g). The trace elements in the sample were found at different percentage levels which play a key role in the treatment of diseases. PMID:26758866

  11. Cadmium stress antioxidant responses and root-to-shoot communication in grafted tomato plants.

    PubMed

    Gratão, Priscila Lupino; Monteiro, Carolina Cristina; Tezotto, Tiago; Carvalho, Rogério Falleiros; Alves, Letícia Rodrigues; Peters, Leila Priscila; Azevedo, Ricardo Antunes

    2015-10-01

    Many aspects related to ROS modulation of signaling networks and biological processes that control stress responses still remain unanswered. For this purpose, the grafting technique may be a powerful tool to investigate stress signaling and specific responses between plant organs during stress. In order to gain new insights on the modulation of antioxidant stress responses mechanisms, gas-exchange measurements, lipid peroxidation, H2O2 content, proline, superoxide dismutase (SOD), catalase (CAT), glutathione reductase (GR), ascorbate peroxidase (APX) and guaiacol peroxidase (GPOX) were analyzed in Micro-Tom grafted plants submitted to cadmium (Cd). The results observed revealed that higher amounts of Cd accumulated mainly in the roots and rootstocks when compared to leaves and scions. Macronutrients uptake (Ca, S, P and Mg) decreased in non-grafted plants, but differed among plant parts in all grafted plants. The results showed that the accumulation of proline observed in scions of grafted plants could be associated to the lower MDA contents in the scions of grafted plants. In the presence of Cd, non-grafted plants displayed increased CAT, GR, GPOX and APX activities for both tissues, whilst grafted plants revealed distinct trends that clearly indicate signaling responses from the rootstocks, allowing sufficient time to activate defense mechanisms in shoot. The information available concerning plants subjected to grafting can provide a better understanding of the mechanisms of Cd detoxification involving root-to-shoot signaling, opening new possibilities on strategies which can be used to manipulate heavy metal tolerance, since antioxidant systems are directly involved in such mechanism.

  12. Antioxidant activity of polysaccharide extracted from Ganoderma lucidum using response surface methodology.

    PubMed

    Kan, Yongjun; Chen, Tiqiang; Wu, Yanbin; Wu, Jianguo; Wu, Jinzhong

    2015-01-01

    Superfine grinding technology was applied for polysaccharide extraction from the fruiting bodies of Ganoderma lucidum, and response surface methodology (RSM) was used to optimize the effects of processing parameters on polysaccharide extraction yield. Results showed that the maximum yield of G. lucidum polysaccharides (GLP) was obtained at an optimum condition: extraction time 137 min, extraction temperature 66 ̊C, the ratio of water to material 35 mL/g, and the GLP extracting yield reached 2.44% under this condition. GLP were precipitated into three crude polysaccharides, viz. GLP40, GLP60 and GLP80. The basic characterization of polysaccharides was determined by using HPLC and FT-IR methods. GLP, GLP80, GLP60, and GLP40 were composed of Man, Rib, Glc, Gal and Fuc with the molar ratios of 1.27:0.36:22.89:1.61:0.33, 1.40:0.31:23.02:3.46:0.91, 0.96:0.34:25.76:2.47:0.46, and 2.81:1.42:23.83:1.61:0.33, respectively. The result of FT-IR suggested that the monosaccharide residue of the four polysaccharides was β-pyranoid ring. Moreover, the antioxidant activities of these four polysaccharides were evaluated. The results showed that GLP80 had the best reducing power, DPPH radical scavenging ability and oxygen radical scavenging ability followed by GLP, GLP60 and GLP40. Our results demonstrated that RSM might be a valuable technique for optimizing the efficient extraction of GLP, and G. lucidum could be considered as sources of natural antioxidants and preservatives of food industry. Moreover, polysaccharides, especially GLP80, extracted from the fruiting bodies of G. lucidum, exhibited promising antioxidant activities.

  13. Measures of antioxidant status of the horse in response to selenium depletion and repletion.

    PubMed

    Brummer, M; Hayes, S; Dawson, K A; Lawrence, L M

    2013-05-01

    Selenium plays a role in the antioxidant mechanism via the selenoenzyme glutathione peroxidase (GSH-Px). Change in Se status because of Se depletion or supplementation is associated with a change in GSH-Px activity and could potentially affect antioxidant status. This study evaluated the impact of change in Se status on measures of antioxidant status and oxidative stress in adult horses. Twenty-eight horses were blocked by age and gender and were randomly allocated to 1 of 4 dietary treatment groups: low Se (LS), adequate Se (AS), high organic Se (SP), and high inorganic Se (SS). For 196 d, LS, SP, and SS received a low-Se diet (0.06 mg Se/kg DM) to allow for depletion of Se stores, whereas AS received an adequate Se diet (0.12 mg Se/kg DM). Then, for the next 189 d, LS and AS were maintained on the same diets, whereas SP was supplemented with Se-yeast and SS with sodium selenite to allow for a total dietary Se intake of 0.3 mg Se/kg DM. Blood samples were collected throughout the study. Variables of interest included whole blood Se and GSH-Px activity, serum vitamin E concentration, total antioxidant capacity (TAC), serum malondialdehyde (MDA), and triiodothyronine and thyroxine concentrations. Data were analyzed using ANOVA with repeated measures. Whole blood Se and GSH-Px activity decreased in LS, SP, and SS during the depletion phase and increased in SP and SS with supplementation (treatment × time, P < 0.001). At the conclusion of the supplementation period, GSH-Px activity was greater in SP and SS compared with AS and LS (P < 0.05). Vitamin E status remained adequate throughout the study, and no differences existed between treatments. Serum TAC did not change in response to Se depletion or repletion. Serum MDA was greater for AS than LS during depletion (P < 0.05) but similar across treatments after supplementation. Overall, change in Se status did not have a large impact on TAC or MDA, possibly because the horses maintained an adequate vitamin E status

  14. Arsenic-induced responses in Pityrogramma calomelanos (L.) Link: Arsenic speciation, mineral nutrition and antioxidant defenses.

    PubMed

    Campos, N V; Arcanjo-Silva, S; Viana, I B; Batista, B L; Barbosa, F; Loureiro, M E; Ribeiro, C; Azevedo, A A

    2015-12-01

    Arsenic (As) hyperaccumulation trait has been described in a limited number of fern species. The physiological basis of hyperaccumulation remains unclear, especially in non-Pteris species such as Pityrogramma calomelanos. Aiming at a better understanding of As-induced responses, P. calomelanos plants were exposed to 1 mM As for 21 days and compared with control plants. Chemical analyses revealed that As accumulation was ten times higher in pinnae then in roots and stipes. In pinnae, As was present mainly as arsenite, whereas arsenate was the dominant form in stipes and roots. Arsenic promoted an increase in antioxidant enzyme activities in both fern parts and several alterations in mineral nutrition, especially with regard to P and K. A higher content of non-protein thiols was observed in pinnae of plants exposed to As, whereas As induced the increase in lipid peroxidation in roots. The results showed that Pityrogramma calomelanos shares with Pteris vittata several aspects of As metabolism. High root-shoot As translocation showed to be essential to avoid toxic effects in roots, since the root is more sensitive to the metalloid. The higher capacity of P. calomelanos to sequester arsenite in the pinna and its efficient antioxidant system maintain the reactive oxygen species at a low level, thus enhancing the continuous accumulation of As. Molecular investigations are needed to elucidate the evolution of As-tolerance mechanisms in Pteridaceae species, especially with regard to membrane transporters and ROS signaling.

  15. Optimization of a surfactant-free antioxidant formulation using response surface methodology.

    PubMed

    Almeida, Isabel F; Costa, Paulo C; Bahia, M Fernanda

    2014-01-01

    Topical application of natural antioxidants has proven to be effective in protecting the skin against ultraviolet radiation-mediated oxidative damage. In previous studies, a Castanea sativa leaf ethanol:water (7:3) extract exhibited scavenging activity against different reactive oxygen species that are thought to contribute to oxidative damage in the skin. Its stability was shown to be enhanced in the presence of glycerine, and therefore a glycerine-based formulation with Carbopol 940 and liquid paraffin (LP) was developed as base. In this work, the influence of the glycerine and LP contents on the textural properties of the topical base and on the antioxidant activity of the formulation with C. sativa extract was evaluated using response surface methodology after 30 d storage at 20 °C and 40 °C. The textural analysis was performed in a texturometer, by carrying out a spreadability test. Paretto charts showed that both glycerine and LP contents significantly influenced the textural properties of the formulations (p < 0.05). LP presented the major influence. DPPH scavenging activity was not related to any of the studied ingredients. These conclusions were valid both for 20 °C and 40 °C storage. This optimization study provided valuable information to support the development of a semisolid base for C. sativa extract leading to the conclusion that the selection of these ingredients contents can be guided exclusively by the desirable textural properties. PMID:23336810

  16. Pitx2 promotes heart repair by activating the antioxidant response after cardiac injury.

    PubMed

    Tao, Ge; Kahr, Peter C; Morikawa, Yuka; Zhang, Min; Rahmani, Mahdis; Heallen, Todd R; Li, Lele; Sun, Zhao; Olson, Eric N; Amendt, Brad A; Martin, James F

    2016-06-01

    Myocardial infarction results in compromised myocardial function and heart failure owing to insufficient cardiomyocyte self-renewal. Unlike many vertebrates, mammalian hearts have only a transient neonatal renewal capacity. Reactivating primitive reparative ability in the mature mammalian heart requires knowledge of the mechanisms that promote early heart repair. By testing an established Hippo-deficient heart regeneration mouse model for factors that promote renewal, here we show that the expression of Pitx2 is induced in injured, Hippo-deficient ventricles. Pitx2-deficient neonatal mouse hearts failed to repair after apex resection, whereas adult mouse cardiomyocytes with Pitx2 gain-of-function efficiently regenerated after myocardial infarction. Genomic analyses indicated that Pitx2 activated genes encoding electron transport chain components and reactive oxygen species scavengers. A subset of Pitx2 target genes was cooperatively regulated with the Hippo pathway effector Yap. Furthermore, Nrf2, a regulator of the antioxidant response, directly regulated the expression and subcellular localization of Pitx2. Pitx2 mutant myocardium had increased levels of reactive oxygen species, while antioxidant supplementation suppressed the Pitx2 loss-of-function phenotype. These findings reveal a genetic pathway activated by tissue damage that is essential for cardiac repair. PMID:27251288

  17. Transcriptional and antioxidative responses to endogenous polyunsaturated fatty acid accumulation in yeast.

    PubMed

    Andrisic, Luka; Collinson, Emma J; Tehlivets, Oksana; Perak, Eleonora; Zarkovic, Tomislav; Dawes, Ian W; Zarkovic, Neven; Cipak Gasparovic, Ana

    2015-01-01

    Pathophysiology of polyunsaturated fatty acids (PUFAs) is associated with aberrant lipid and oxygen metabolism. In particular, under oxidative stress, PUFAs are prone to autocatalytic degradation via peroxidation, leading to formation of reactive aldehydes with numerous potentially harmful effects. However, the pathological and compensatory mechanisms induced by lipid peroxidation are very complex and not sufficiently understood. In our study, we have used yeast capable of endogenous PUFA synthesis in order to understand the effects triggered by PUFA accumulation on cellular physiology of a eukaryotic organism. The mechanisms induced by PUFA accumulation in S. cerevisiae expressing Hevea brasiliensis Δ12-fatty acid desaturase include down-regulation of components of electron transport chain in mitochondria as well as up-regulation of pentose-phosphate pathway and fatty acid β-oxidation at the transcriptional level. Interestingly, while no changes were observed at the transcriptional level, activities of two important enzymatic antioxidants, catalase and glutathione-S-transferase, were altered in response to PUFA accumulation. Increased intracellular glutathione levels further suggest an endogenous oxidative stress and activation of antioxidative defense mechanisms under conditions of PUFA accumulation. Finally, our data suggest that PUFA in cell membrane causes metabolic changes which in turn lead to adaptation to endogenous oxidative stress. PMID:25280400

  18. Age specific responses to acute inhalation of diffusion flame soot particles: Cellular injury and the airway antioxidant response

    PubMed Central

    Van Winkle, Laura S.; Chan, Jackie K.W.; Anderson, Donald S.; Kumfer, Benjamin M.; Kennedy, Ian M.; Wexler, Anthony S; Wallis, Christopher; Abid, Aamir D.; Sutherland, Katherine M.; Fanucchi, Michelle V.

    2011-01-01

    Current studies of particulate matter (PM) are confounded by the fact that PM is a complex mixture of primary (crustal material, soot, metals) and secondary (nitrates, sulfates and organics formed in the atmosphere) compounds with considerable variance in composition by sources and location. We have developed a laboratory-based PM that is replicable, does not contain dust or metals and that can be used to study specific health effects of PM composition in animal models. We exposed both neonatal (7 days of age) and adult rats to a single 6-hr exposure of laboratory generated fine diffusion flame soot (DFP; 170 ug/m3), or filtered air. Pulmonary gene and protein expression as well as indicators of cytotoxicity were evaluated 24 hours after exposure. Although DFP exposure did not alter airway epithelial cell composition in either neonates or adults, increased LDH activity was found in the bronchoalveolar lavage fluid of neonates indicating an age-specific increase in susceptibility. In adults, 16 genes were differentially expressed as a result of DFP exposure while only 6 genes were altered in the airways of neonates. Glutamate cytsteine ligase protein was increased in abundance in both DFP exposed neonates and adults indicating an initiation of antioxidant responses involving the synthesis of glutathione. DFP significantly decreased catalase gene expression in adult airways, although catalase protein expression was increased by DFP in both neonates and adults. We conclude that key airway antioxidant enzymes undergo changes in expression in response to a moderate PM exposure that does not cause frank epithelial injury and that neonates have a different response pattern than adults. PMID:20961279

  19. Dynamics of rhizosphere properties and antioxidative responses in wheat (Triticum aestivum L.) under cadmium stress.

    PubMed

    Li, Yonghua; Wang, Li; Yang, Linsheng; Li, Hairong

    2014-04-01

    In this study, we performed a rhizobox experiment to examine the dynamic changes in the rhizosphere properties and antioxidant enzyme responses of Triticum aestivum L. under three levels of cadmium stress. A set of micro-techniques (i.e., Rhizobox and Rhizon SMS) were applied for the dynamically non-destructive collection of the rhizosphere soil solution to enable the observation at a high temporal resolution. The dynamics of soluble cadmium and dissolved organic carbon (DOC) in the rhizosphere soil solutions of the Triticum aestivum L. were characterised by the sequence week 0 after sowing (WAS0)<3 weeks after sowing (WAS3)<10 weeks after sowing (WAS10), whereas the soil solution pH was found to follow an opposite distribution pattern. Systematically, both superoxide dismutase (SOD) and catalase (CAT) activities in the leaves of the Triticum aestivum L. increased concomitantly with increasing cadmium levels (p>0.05) and growth duration (p<0.05), whilst ascorbate peroxidase (APX) activity was induced to an elevated level at moderate cadmium stress with a decrease at high cadmium stress (p>0.05). These results suggested the enhancement of DOC production and the greater antioxidant enzyme activities were two important protective mechanisms of Triticum aestivum L. under cadmium stress, whereas rhizosphere acidification might be an important mechanism for the mobilisation of soil cadmium. The results also revealed that plant-soil interactions strongly influence the soil solution chemistry in the rhizosphere of Triticum aestivum L., that, in turn, can stimulate chemical and biochemical responses in the plants. In most cases, these responses to cadmium stress were sensitive and might allow us to develop strategies for reducing the risks of the cadmium contamination to crop production.

  20. Lettuce irrigated with contaminated water: Photosynthetic effects, antioxidative response and bioaccumulation of microcystin congeners.

    PubMed

    Bittencourt-Oliveira, Maria do Carmo; Cordeiro-Araújo, Micheline Kézia; Chia, Mathias Ahii; Arruda-Neto, João Dias de Toledo; de Oliveira, Ênio Tiago; dos Santos, Flávio

    2016-06-01

    The use of microcystins (MCs) contaminated water to irrigate crop plants represents a human health risk due to their bioaccumulation potential. In addition, MCs cause oxidative stress and negatively influence photosynthetic activities in plants. The present study was aimed at investigating the effect of MCs on photosynthetic parameters and antioxidative response of lettuce. Furthermore, the bioaccumulation factor (BAF) of total MCs, MC-LR and MC-RR in the vegetable after irrigation with contaminated water was determined. Lettuce crops were irrigated for 15 days with water containing cyanobacterial crude extracts (Microcystis aeruginosa) with MC-LR (0.0, 0.5, 2.0, 5.0 and 10.0 µg L(-1)), MC-RR (0.0, 0.15, 0.5, 1.5 and 3.0 µg L(-1)) and total MCs (0.0, 0.65, 2.5, 6.5 and 13.0 µg L(-1)). Increased net photosynthetic rate, stomatal conductance, leaf tissue transpiration and intercellular CO2 concentration were recorded in lettuce exposed to different MCs concentrations. Antioxidant response showed that glutathione S-transferase activity was down-regulated in the presence of MCs. On the other hand, superoxide dismutase, catalase and peroxidase activities were upregulated with increasing MCs concentrations. The bioaccumulation factor (BAF) of total MCs and MC-LR was highest at 6.50 and 5.00 µg L(-1), respectively, while for MC-RR, the highest BAF was recorded at 1.50 µg L(-1) concentration. The amount of total MCs, MC-LR and MC-RR bioacumulated in lettuce was highest at the highest exposure concentrations. However, at the lowest exposure concentration, there were no detectable levels of MC-LR, MC-RR and total MCs in lettuce. Thus, the bioaccumulation of MCs in lettuce varies according to the exposure concentration. In addition, the extent of physiological response of lettuce to the toxins relies on exposure concentrations.

  1. Metalliferous and non-metalliferous populations of Viola tricolor represent similar mode of antioxidative response.

    PubMed

    Słomka, Aneta; Libik-Konieczny, Marta; Kuta, Elzbieta; Miszalski, Zbigniew

    2008-10-01

    Heavy metal-contaminated sites are excellent areas to examine the antioxidative machinery responsible for physiological adaptations of many plant species. Superoxide dismutase (SOD), guaiacol peroxide (GPX), ascorbate peroxide (APX), catalase (CAT) activity and hydrogen peroxide (H(2)O(2)) content were analyzed in leaves and roots of Viola tricolor (Viola) from contaminated soils ('Bukowno', 'Saturn', 'Warpie' heaps), and non-contaminated soil ('Zakopane meadow') to examine the level of oxidative stress and antioxidative response. In leaves, six isoforms of SOD were recognized. Roots possessed two additional bands, named manganese superoxide dismutase (MnSOD)-like form (MnSODI) and Cu/ZnSOD-like form (Cu/ZnSODIV). The H(2)O(2) content in leaves ranged from 554 to 5 098 micromol H(2)O(2)/gf.w. and was negatively correlated with CAT activity. The non-contaminated population was characterized by the lowest CAT activity combined with the highest H(2)O(2) concentration. Two isoforms of CAT, CAT-1 and CAT-2, were recognized in leaves of plants from non-contaminated and contaminated sites, respectively. In roots of individuals from two heaps ('Warpie' and 'Saturn'), two distinct bands for each CAT isoform were observed. A slower migrating band may be an aggregate, exhibiting CAT and MnSODs activities. Both peroxidases (APX and GPX) presented the same pattern of activity, depending on the organ, indicating that in leaves and roots APX and GPX were regulated in parallel. Differences in enzyme activities and H(2)O(2) content between plants from different contaminated sites were statistically significant, but were tightly maintained at a very similar level. Prolonged and permanent heavy metal stress evoked a very similar mode of antioxidative response in specimens of analyzed metalliferous populations not causing measurable oxidative stress. Thus, our results clearly indicate that V. tricolor is a taxon well adapted to heavy metal-contaminated soils, and that differences in

  2. Effect of Chronic Exposure to Prometryne on Oxidative Stress and Antioxidant Response in Red Swamp Crayfish (Procambarus clarkii)

    PubMed Central

    Stará, Alžběta; Kouba, Antonín; Velíšek, Josef

    2014-01-01

    The aim of the study was to investigate effects of the triazine herbicide prometryne on red swamp crayfish on the basis of oxidative stress, antioxidant indices in hepatopancreas and muscle, and histopathology of hepatopancreas. Crayfish were exposed to prometryne concentrations of 0.51 μg L−1, 0.144 mg L−1, and 1.144 mg L−1 for 11 and 25 days. Indices of oxidative stress (thiobarbituric acid reactive substances (TBARS)), and antioxidant parameters (superoxide dismutase (SOD), catalase (CAT), and glutathione reductase (GR)) in crayfish muscle and hepatopancreas were measured. Chronic exposure to prometryne did not showed the impact of oxidative damage to cells. Changes activity of the antioxidant enzymes SOD, CAT, and GR were observed in all tested concentrations to prometryne for 11 and 25 days (P < 0.01) as compared with the control group. We did not see any differences in histopatological examination to hepatopancreas. Prolonged exposure of prometryne did not result in oxidative damage to cell lipids and proteins, but it led to changes in antioxidant activity in crayfish tissues. Changes in antioxidant systems were also observed in the environmental prometryne concentration of 0.51 μg L−1. The results suggest that antioxidant responses may have potential as biomarkers for monitoring residual triazine herbicides in aquatic environments. PMID:24757669

  3. Effect of vitamin C and folic acid on seed vigour response and phenolic-linked antioxidant activity.

    PubMed

    Burguieres, Elizabeth; McCue, Patrick; Kwon, Young-In; Shetty, Kalidas

    2007-05-01

    Folic acid and vitamin C were used in the concentration range of 0-500muM as exogenous growth enhancers to stimulate pea (Pisum sativum) seedling vigour. The results suggest that a concentration of 50muM folic acid and 500muM vitamin C were optimum in maximally enhancing seed vigour and potentially seedling performance according to both agronomic and biochemical seed vigour parameters. Results indicated that germination percentage, shoot weight, shoot height, and root length were enhanced in folic acid and vitamin C treated plants compared to control plants. The levels of enhanced phenolic content in response to folic acid and vitamin C treatments were highest on days 8 and 10. Evaluation of critical biochemical parameters indicated that the average glucose-6-phosphate dehydrogenase (G6PDH) activity and proline content in response to treatments were higher than control and correlated to enhanced phenolic content and DPPH-based antioxidant activity. Key enzymes, guaiacol peroxidase (GPX), superoxide dismutase (SOD), and catalase (CAT) were also higher in response to treatments and correlated to enhanced phenolic content and DPPH-based antioxidant activity. Taken together, these studies support the hypothesis that the proline-linked pentose phosphate pathway stimulates phenolic synthesis and related free-radical scavenging antioxidant activity. Further, this proline-linked pentose phosphate pathway stimulation in response to folic acid and vitamin C was also correlated to antioxidant enzyme response indicated by the stimulation of GPX, SOD, and CAT activities. Therefore, this study indicates the enhancement of seed vigour response by folic acid and vitamin C as reflected in both agronomic and biochemical responses, and this occurred through the stimulation of phenolic-linked antioxidant response that is likely positively modulated through the proline-linked pentose phosphate pathway.

  4. Vibration Response of Multi Storey Building Using Finite Element Modelling

    NASA Astrophysics Data System (ADS)

    Chik, T. N. T.; Zakaria, M. F.; Remali, M. A.; Yusoff, N. A.

    2016-07-01

    Interaction between building, type of foundation and the geotechnical parameter of ground may trigger a significant effect on the building. In general, stiffer foundations resulted in higher natural frequencies of the building-soil system and higher input frequencies are often associated with other ground. Usually, vibrations transmitted to the buildings by ground borne are often noticeable and can be felt. It might affect the building and become worse if the vibration level is not controlled. UTHM building is prone to the ground borne vibration due to closed distance from the main road, and the construction activities adjacent to the buildings. This paper investigates the natural frequency and vibration mode of multi storey office building with the presence of foundation system and comparison between both systems. Finite element modelling (FEM) package software of LUSAS is used to perform the vibration analysis of the building. The building is modelled based on the original plan with the foundation system on the structure model. The FEM results indicated that the structure which modelled with rigid base have high natural frequency compare to the structure with foundation system. These maybe due to soil structure interaction and also the damping of the system which related to the amount of energy dissipated through the foundation soil. Thus, this paper suggested that modelling with soil is necessary to demonstrate the soil influence towards vibration response to the structure.

  5. Mapping polycomb response elements at the Drosophilla melanogaster giant locus.

    PubMed

    Abed, Jumana AlHaj; Cheng, Connie L; Crowell, Chase R; Madigan, Laura L; Onwuegbuchu, Erica; Desai, Siddhi; Benes, Judith; Jones, Richard S

    2013-12-01

    Polycomb-group (PcG) proteins are highly conserved epigenetic transcriptional regulators. They are capable of either maintaining the transcriptional silence of target genes through many cell cycles or enabling a dynamic regulation of gene expression in stem cells. In Drosophila melanogaster, recruitment of PcG proteins to targets requires the presence of at least one polycomb response element (PRE). Although the sequence requirements for PREs are not well-defined, the presence of Pho, a PRE-binding PcG protein, is a very good PRE indicator. In this study, we identify two PRE-containing regions at the PcG target gene, giant, one at the promoter, and another approximately 6 kb upstream. PRE-containing fragments, which coincide with localized presence of Pho in chromatin immunoprecipitations, were shown to maintain restricted expression of a lacZ reporter gene in embryos and to cause pairing-sensitive silencing of the mini-white gene in eyes. Our results also reinforce previous observations that although PRE maintenance and pairing-sensitive silencing activities are closely linked, the sequence requirements for these functions are not identical. PMID:24170735

  6. Optimization of Preparation of Antioxidative Peptides from Pumpkin Seeds Using Response Surface Method

    PubMed Central

    Fan, Sanhong; Hu, Yanan; Li, Chen; Liu, Yanrong

    2014-01-01

    Protein isolates of pumpkin (Cucurbita pepo L) seeds were hydrolyzed by acid protease to prepare antioxidative peptides. The hydrolysis conditions were optimized through Box-Behnken experimental design combined with response surface method (RSM). The second-order model, developed for the DPPH radical scavenging activity of pumpkin seed hydrolysates, showed good fit with the experiment data with a high value of coefficient of determination (0.9918). The optimal hydrolysis conditions were determined as follows: hydrolyzing temperature 50°C, pH 2.5, enzyme amount 6000 U/g, substrate concentration 0.05 g/ml and hydrolyzing time 5 h. Under the above conditions, the scavenging activity of DPPH radical was as high as 92.82%. PMID:24637721

  7. Optimization of preparation of antioxidative peptides from pumpkin seeds using response surface method.

    PubMed

    Fan, Sanhong; Hu, Yanan; Li, Chen; Liu, Yanrong

    2014-01-01

    Protein isolates of pumpkin (Cucurbita pepo L) seeds were hydrolyzed by acid protease to prepare antioxidative peptides. The hydrolysis conditions were optimized through Box-Behnken experimental design combined with response surface method (RSM). The second-order model, developed for the DPPH radical scavenging activity of pumpkin seed hydrolysates, showed good fit with the experiment data with a high value of coefficient of determination (0.9918). The optimal hydrolysis conditions were determined as follows: hydrolyzing temperature 50°C, pH 2.5, enzyme amount 6000 U/g, substrate concentration 0.05 g/ml and hydrolyzing time 5 h. Under the above conditions, the scavenging activity of DPPH radical was as high as 92.82%.

  8. High-throughput genotoxicity assay identifies antioxidants as inducers of DNA damage response and cell death

    PubMed Central

    Fox, Jennifer T.; Sakamuru, Srilatha; Huang, Ruili; Teneva, Nedelina; Simmons, Steven O.; Xia, Menghang; Tice, Raymond R.; Austin, Christopher P.; Myung, Kyungjae

    2012-01-01

    Human ATAD5 is a biomarker for identifying genotoxic compounds because ATAD5 protein levels increase posttranscriptionally in response to DNA damage. We screened over 4,000 compounds with a cell-based quantitative high-throughput ATAD5-luciferase assay detecting genotoxic compounds. We identified 22 antioxidants, including resveratrol, genistein, and baicalein, that are currently used or investigated for the treatment of cardiovascular disease, type 2 diabetes, osteopenia, osteoporosis, and chronic hepatitis, as well as for antiaging. Treatment of dividing cells with these compounds induced DNA damage and resulted in cell death. Despite their genotoxic effects, resveratrol, genistein, and baicalein did not cause mutagenesis, which is a major side effect of conventional anticancer drugs. Furthermore, resveratrol and genistein killed multidrug-resistant cancer cells. We therefore propose that resveratrol, genistein, and baicalein are attractive candidates for improved chemotherapeutic agents. PMID:22431602

  9. N6-isopentenyladenosine and analogs activate the NRF2-mediated antioxidant response

    PubMed Central

    Dassano, Alice; Mancuso, Mariateresa; Giardullo, Paola; Cecco, Loris De; Ciuffreda, Pierangela; Santaniello, Enzo; Saran, Anna; Dragani, Tommaso A.; Colombo, Francesca

    2014-01-01

    N6-isopentenyladenosine (i6A), a naturally occurring modified nucleoside, inhibits the proliferation of human tumor cell lines in vitro, but its mechanism of action remains unclear. Treatment of MCF7 human breast adenocarcinoma cells with i6A or with three synthetic analogs (allyl6A, benzyl6A, and butyl6A) inhibited growth and altered gene expression. About 60% of the genes that were differentially expressed in response to i6A treatment were also modulated by the analogs, and pathway enrichment analysis identified the NRF2-mediated oxidative stress response as being significantly modulated by all four compounds. Luciferase reporter gene assays in transfected MCF7 cells confirmed that i6A activates the transcription factor NRF2. Assays for cellular production of reactive oxygen species indicated that i6A and analogs had antioxidant effects, reducing basal levels and inhibiting the H2O2- or 12-O-tetradecanoylphorbol-13-acetate (TPA)-induced production in MCF7 or dHL-60 (HL-60 cells induced to differentiate along the neutrophilic lineage) cell lines, respectively. In vivo, topical application of i6A or benzyl6A to mouse ears prior to TPA stimulation lessened the inflammatory response and significantly reduced the number of infiltrating neutrophils. These results suggest that i6A and analogs trigger a cellular response against oxidative stress and open the possibility of i6A and benzyl6A being used as topical anti-inflammatory drugs. PMID:24688894

  10. In vivo ozone exposure induces antioxidant/stress-related responses in murine lung and skin.

    PubMed

    Valacchi, Giuseppe; Pagnin, Elisa; Corbacho, Ana M; Olano, Estibaliz; Davis, Paul A; Packer, Lester; Cross, Carroll E

    2004-03-01

    Lung and skin are the organs directly exposed to environmental pollution. Ozone (O(3)) is a toxic, oxidant air pollutant, and exposure has been shown to induce antioxidant depletion as well as oxidation of lipids and proteins within the outermost skin layer (stratum corneum) and the lung respiratory tract lining fluids (RTLFs). To further define skin and lung responses to O(3) exposure, SKH-1 hairless mice were exposed to either 0.8 ppm of O(3) (a level occasionally reached in very polluted areas) or ambient air 6 h/day for 6 consecutive days. O(3) exposure resulted in the depletion of alpha-tocopherol in lung and plasma and induction in both skin and lung of heme oxygenase 1, cyclooxygenase 2, and proliferating cell nuclear antigen. O(3)-exposed animals showed a similar extent of upregulation of COX-2 and PCNA in lung and skin, whereas HO-1 was more responsive in skin than in lung (7-fold induction vs. 2-fold induction). In addition to these measures of response to oxidative stress, O(3) exposure led to the activation of nuclear factor kappaB measured as IkappaBalpha phosphorylation in both tissues. We conclude that in this model, O(3) at high pollutant levels is able to affect both lung and skin biology, inducing depletion of alpha-tocopherol and inducing stress-related responses in both skin epidermis and respiratory tract epithelium.

  11. [Antioxidative response of Phytolacca americana and Nicotiana tabacum to manganese stresses].

    PubMed

    Zhang, Yu-xiu; Huang, Zhi-bo; Zhang, Hong-mei; Li, Lin-feng; Chai, Tuan-yao

    2009-12-01

    Plant species capable of accumulating heavy metals are of considerable interest for phytoremediation and phytomining. The mechanism of Mn tolerance/hyperaccumulate in Phytolacca americana L. is less known. To elucidate the role of antioxidative enzyme in response to Mn, the 6-week-old seedling of Mn hyperaccumulator P. americana and non-accumulator-tobacco (Nicotiana tabacum) were exposed to half strength Hoagland solution with 1 mmol x L(-1) or 3 mmol x L(-1) MnCl2 for 4 days. The photosynthetic rate in P. americana decreased more slowly than that in tobacco, while the MDA content and electrolyte leakage in tobacco increased more rapidly than that in P. americana. For example, after exposure to 1 mmol x L(-1) Mn for 4 days, the photosynthetic rates of P. americana and tobacco in comparison to the control reduced by 13.3% and 75.5%, respectively. The MDA content and electrolyte leakage in tobacco increased by 347.3% and 120.1%, respectively, whereas Mn had no marked effect on both of it in P. americana, indicated that the oxidative damage in tobacco was more serious than that in P. americana. The activities of SOD and POD of both species increased rapidly with elevated Mn concentration and exposure time in both species, the increase of SOD activity in P. americana was higher than that in tobacco. CAT activity in tobacco declined rapidly, while the activity of CAT in P. americana was increased. The activities of SOD, POD and CAT in P. americana upon 1 mmol x L(-1) Mn exposure increased by 161.1%, 111.3% and 17.5%, respectively. The activities of SOD and POD in tobacco increased by 55.5% and 206.0%, respectively, while CAT activity decreased by 15.6%, indicating that the antioxidative enzymes in P. americana, particularly in CAT,could fully scavenge the reactive oxygen species generated by Mn toxicity. These results collectively indicate that the enzymatic antioxidation capacity is one of the important mechanisms responsible for Mn tolerance in hyperaccumulator plant

  12. A temporal analysis of the relationships between social stress, humoral immune response and glutathione-related antioxidant defenses.

    PubMed

    Gonçalves, Luciane; Dafre, Alcir Luiz; Carobrez, Sonia Gonçalves; Gasparotto, Odival Cezar

    2008-10-10

    The exposure to different kinds of stress impacts on the reactive oxygen species production with potential risk to the integrity of the tissues. Psychological or biological stress is responsible for a significant increase in the oxidative stress markers and also for activation of the antioxidant defense system. In this study, we analyzed the relationships between social stress, humoral immune response and glutathione-related antioxidant defenses. Groups of male Swiss mice were subjected to different lengths of social stress exposure (social confrontation) which varied from 1 up to 13 days. As a biological stressor, 10(9) sheep red blood cells (SRBC)/mL were injected by intraperitoneal route. As controls, animals not subjected to social stress and/or injected with vehicle solution were used. The serum samples and the cerebral cortex were collected at 4 h, 3, 5, 7, 9, 11, and 13 days after the end of social confrontation. The results indicated that the antioxidant enzymes activities were affected by psychological as well as by biological stressor. These alterations were dependent on the timing of stress exposure which resulted in a positive or in a negative correlation between the antibody titres to SRBC and antioxidant enzymes. We also discuss the possible role of SRBC injection in the modulation of the effects of psychosocial stress on antioxidant metabolism.

  13. Induction of Antioxidant and Heat Shock Protein Responses During Torpor in the Gray Mouse Lemur, Microcebus murinus.

    PubMed

    Wu, Cheng-Wei; Biggar, Kyle K; Zhang, Jing; Tessier, Shannon N; Pifferi, Fabien; Perret, Martine; Storey, Kenneth B

    2015-04-01

    A natural tolerance of various environmental stresses is typically supported by various cytoprotective mechanisms that protect macromolecules and promote extended viability. Among these are antioxidant defenses that help to limit damage from reactive oxygen species and chaperones that help to minimize protein misfolding or unfolding under stress conditions. To understand the molecular mechanisms that act to protect cells during primate torpor, the present study characterizes antioxidant and heat shock protein (HSP) responses in various organs of control (aroused) and torpid gray mouse lemurs, Microcebus murinus. Protein expression of HSP70 and HSP90α was elevated to 1.26 and 1.49 fold, respectively, in brown adipose tissue during torpor as compared with control animals, whereas HSP60 in liver of torpid animals was 1.15 fold of that in control (P<0.05). Among antioxidant enzymes, protein levels of thioredoxin 1 were elevated to 2.19 fold in white adipose tissue during torpor, whereas Cu-Zn superoxide dismutase 1 levels rose to 1.1 fold in skeletal muscle (P<0.05). Additionally, total antioxidant capacity was increased to 1.6 fold in liver during torpor (P<0.05), while remaining unchanged in the five other tissues. Overall, our data suggest that antioxidant and HSP responses are modified in a tissue-specific manner during daily torpor in gray mouse lemurs. Furthermore, our data also show that cytoprotective strategies employed during primate torpor are distinct from the strategies in rodent hibernation as reported in previous studies.

  14. Sex differences in the acute nasal antioxidant/antielectrophilic response of the rat to inhaled naphthalene.

    PubMed

    Cichocki, Joseph A; Smith, Gregory J; Mendoza, Ryan; Buckpitt, Alan R; Van Winkle, Laura S; Morris, John B

    2014-05-01

    Naphthalene is a nasal carcinogen, inducing respiratory adenomas in male and olfactory neuroblastomas in female rats, respectively. The reasons for the site and sex-specific tumorigenic response are unknown. Naphthalene is bioactivated to electrophilic metabolites; cytotoxicity followed by regenerative cell proliferation is likely involved in the tumorigenic response. To examine sex differences in the acute nasal response to naphthalene, male and female F344 rats were nose-only exposed to 0, 1, 3, 10, or 30 ppm naphthalene vapor for 4 or 6 h. Following exposure, respiratory/transitional mucosa (RTM) and olfactory mucosa (OM) were isolated and analyzed for markers of oxidant/electrophilic stress and/or toxicity, including reduced/oxidized glutathione levels (GSH/GSSG), mRNA levels of electrophile-responsive genes, and epithelial cytoxicity (as measured by membrane permeability to ethidium homodimer-1). Naphthalene caused significant depletion of GSH in RTM and OM with no increase in GSSG. Cytotoxicity was apparent at concentrations of 15 and 30 ppm. No consistent sex differences were observed in these responses. Sex differences were observed in the induction of antielectrophilic genes in OM: glutamyl cysteine ligase (catalytic subunit) (Gclc), NADPH quinone oxidase 1 (Nqo1), and heme oxygenase 1 (Hmox1) were all induced to a greater extent in the male OM compared with the female. No consistent sex differences were observed in the RTM. Although the mechanism of the sex difference in the RTM adenoma response remains enigmatic, sex differences in the induction of antioxidant/electrophile-responsive genes may contribute to the heightened sensitivity of the female OM to the carcinogenic effects of naphthalene.

  15. Growth at elevated ozone or elevated carbon dioxide concentration alters antioxidant capacity and response to acute oxidative stress in soybean (Glycine max)

    SciTech Connect

    Gillespie, K.M.; Rogers, A.; Ainsworth, E. A.

    2011-01-31

    Soybeans (Glycine max Merr.) were grown at elevated carbon dioxide concentration ([CO{sub 2}]) or chronic elevated ozone concentration ([O{sub 3}]; 90 ppb), and then exposed to an acute O{sub 3} stress (200 ppb for 4 h) in order to test the hypothesis that the atmospheric environment alters the total antioxidant capacity of plants, and their capacity to respond to an acute oxidative stress. Total antioxidant metabolism, antioxidant enzyme activity, and antioxidant transcript abundance were characterized before, immediately after, and during recovery from the acute O{sub 3} treatment. Growth at chronic elevated [O{sub 3}] increased the total antioxidant capacity of plants, while growth at elevated [CO{sub 2}] decreased the total antioxidant capacity. Changes in total antioxidant capacity were matched by changes in ascorbate content, but not phenolic content. The growth environment significantly altered the pattern of antioxidant transcript and enzyme response to the acute O{sub 3} stress. Following the acute oxidative stress, there was an immediate transcriptional reprogramming that allowed for maintained or increased antioxidant enzyme activities in plants grown at elevated [O{sub 3}]. Growth at elevated [CO{sub 2}] appeared to increase the response of antioxidant enzymes to acute oxidative stress, but dampened and delayed the transcriptional response. These results provide evidence that the growth environment alters the antioxidant system, the immediate response to an acute oxidative stress, and the timing over which plants return to initial antioxidant levels. The results also indicate that future elevated [CO{sub 2}] and [O{sub 3}] will differentially affect the antioxidant system.

  16. Influence of salt stress on growth and antioxidant responses of two malus species at callus and plantlet stages

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Soil salinization has become a significant factor limiting apple (Malus domestica L.) production in some areas of China. This study was carried out to investigate the effects of salt stress i.e. 150 mmol/L NaCl in Murashige and Skoog medium on growth and antioxidant responses of 15-d old callus and ...

  17. LACK OF EFFECT OF AGE AND ANTIOXIDANT DEPLETION ON RESPIRATORY RESPONSES TO CONCENTRATED AMBIENT PARTICULATES (CAPS) IN RATS

    EPA Science Inventory

    2003 AAR PM Meeting
    Particulate Matter: Atmospheric Sciences,
    Exposure and the Fourth Colloquium on PM and Human Health

    LACK OF EFFECT OF AGE AND ANTIOXIDANT DEPLETION ON RESPIRATORY RESPONSES TO CONCENTRATED AMBIENT PARTICULATES (CAPs) IN RATS. JA Dye, LC Walsh, C...

  18. Effect of antioxidant supplementation on the adaptive response of human skin fibroblasts to UV-induced oxidative stress.

    PubMed

    Jones, S A; McArdle, F; Jack, C I; Jackson, M J

    1999-01-01

    The effect of supplementation with substances having antioxidant properties on the adaptive responses of human skin fibroblasts to UV-induced oxidative stress was studied in vitro. UVR was found to induce a substantial oxidative stress in fibroblasts, resulting in an increased release of superoxide anions and an increase in lipid peroxidation (shown by an elevated malonaldehyde content). Sub-lethal doses of UVR were also found to induce adaptive responses in the fibroblast antioxidant defences, with a transient rise in catalase and superoxide dismutase activities followed by a slower, large increase in cellular glutathione content. Supplementation of the fibroblasts with the antioxidants, Trolox (a water soluble analogue of alpha-tocopherol), ascorbic acid or beta-carotene, had differential effects on these responses. Trolox supplementation reduced the UVR-induced cellular oxidative stress and adaptive response in a predictable concentration-dependent manner. This was in contrast to ascorbic acid which increased superoxide release from fibroblasts. At low doses, ascorbate supplements also reduced the magnitude of the adaptive increases in catalase and superoxide dismutase activities and increase in glutathione content. Beta-carotene had a similar effect to ascorbic acid, reducing the extent of the adaptations to UVR at lower doses while simultaneously increasing superoxide release and malonaldehyde content. These in vitro data indicate that only the vitamin E analogue suppressed UVR-induced oxidative stress in a predictable manner and suggest that common dietary antioxidants may not be equally effective in reducing the potential deleterious effects of UVR-induced oxidative stress in skin.

  19. [Preliminary evaluation of the antioxidant trace elements in an Algerian patient with type 2 diabetes: special role of manganese and chromium].

    PubMed

    Harani, Hassiba; Otmane, Amel; Makrelouf, Mohamed; Ouadahi, Nacer; Abdi, Arezki; Berrah, Abdelkrim; Zenati, Akila; Alamir, Barkahoum; Koceir, Elhadj Ahmed

    2012-01-01

    In type 2 diabetes, the relationship between antioxidants and insuline-like trace elements is very complex during oxidative stress, being mediated by hyperglycemia, dyslipidemia and inflammation. We investigated the antioxidant status, particularly Mn and Cr on the diabetes metabolic control, and their interaction with the metabolic syndrome (MS) parameters. The study was undertaken on 278 Algerian diabetic subjects who were divided in 2 groups according to glycated hemoglobin (HbA(1c)) <7% or >7% value, attesting for a good or poor metabolic control of diabetes, respectively. The MS was defined according to NCEP-ATPIII. Insulin resistance was evaluated by HOMA-IR model. The plasma manganese concentrations was significantly increased in both diabetics groups, independently of metabolic control. However, chromium (Cr) seems to play a determinant action in metabolic control, as shown by better values of insulin resistance (HOMA-IR) and HbA(1c). The selenium status was positively correlated with glutathion peroxidase activity. Copper and zinc plasma levels in the diabetic patients were similar to those of control subjects. In conclusion, our results suggest that Mn play a crucial role in antioxidant capacity and we hypothesize that antioxidant defense is preserved in the cytosol (superoxide dismutase Cu/Zn -SOD), whereas it is impaired in mitochondria (Mn-SOD), which makes this cell organelle a true therapeutic target in diabetes. PMID:23207812

  20. Antioxidant activity of seedling growth in selected soybean genotypes (Glycine max (L.) Merrill) responses of submergence

    NASA Astrophysics Data System (ADS)

    Damanik, R. I.; Marbun, P.; Sihombing, L.

    2016-08-01

    In order to better understand the physiological and biochemical responses relating to direct seeding establishment in soybeans, the plant growth rate and antioxidative defense responses of seedlings in seven Indonesian soybean genotypes (Anjasmoro, Detam-1, Detam-2, Dieng, Grobogan, Tanggamus, and Willis) at different submergence periods (4, and 8 days) were examined. Twelve-day old seedlings were hydroponically grown in limited oxygen conditions. The results showed that the chlorophyll content in soybean seedlings was reduced beginning as early as 4 d under submerged condition, except for Detam-1, Detam-2, and Grobogan genotypes. The dry weight and protein concentration of seedlings were significantly higher at control condition (0 d) than those in submerged condition. The activities of superoxide dismutase (SOD) increased linearly until 8 d submerged for all genotypes. On the other hand, our results showed that catalase (CAT) and ascorbate peroxidase (APX) activities did not work together, meaning that CAT is activated and APX deactivated, or vice versa, in response to submergence conditions, except for Grobogan and Tanggamus genotypes which had an effect on both CAT and APX activities. Submergence stress led to a significant increase in glutathione reductase (GR) together with APX activity for Detam-2 and Dieng genotypes at 8 d submerged.

  1. Oxidative Response and Antioxidative Mechanism in Germinating Soybean Seeds Exposed to Cadmium

    PubMed Central

    Yang, Shiyong; Xie, Jianchun; Li, Quanfa

    2012-01-01

    Seeds of soybean (Glycine max L.) exposed to 50 mg/L (Cd50), 100 mg/L (Cd100) and 200 mg/L (Cd200) cadmium solution for 24, 48, 72 and 96 h were examined with reference to Cd accumulation, oxidative stress and antioxidative responses. Soybean seeds accumulated Cd in an exposure time-and dosage-dependent manner. FRAP (ferric reducing ability of plasma) concentration, GSH/hGSH content, and GST activity showed a pronounced exposure time-dependent response. Cd100 enhanced FRAP concentration in germinating soybean seeds as compared to Cd50 treatment after 24 h exposure. Cd200 however increased statistically GST activities after 72 and 96 h exposure. Under all Cd dosages, GSH/hGSH concentrations were depressed with increasing exposure time. Reduction of GSH/hGSH content and concomitant increase of GST activity suggested a possible participation of GSH into GSH-Cd conjugates synthesis. MDA content is a potential biomarker for monitoring Cd phytotoxicity because it responds significantly to treatment dosage, exposure time and dosage × exposure time interaction. Increase of proline content may be a response to acute heavy metal toxicity in soybean seeds. PMID:23066399

  2. Antioxidant responses to simulated acid rain and heavy metal deposition in birch seedlings.

    PubMed

    Koricheva, J; Roy, S; Vranjic, J A; Haukioja, E; Hughes, P R; Hänninen, O

    1997-01-01

    This study measured the responses of different anti-oxidants in 2-year-old birch (Betula pendula Roth) seedlings subjected to simulated acid rain (pH 4.0) and heavy metals (Cu/Ni), applied alone or in combination for 2 months. The applied concentrations of pollutants did not significantly affect seedling biomass or total glutathione levels. Acid rain alone increased superoxide dismutase (SOD) activity both in leaves and roots, while heavy metals alone inhibited SOD activity in roots. Both acid rain and heavy metals applied singly increased ascorbate peroxidase (APX) and guaiacol peroxidase (GPX) activities in leaves but decreased activities in roots. In contrast, acid rain and heavy metal treatments increased glutathione reductase (GR) activity in roots but not in leaves. Spraying birch seedlings with a mixture of acid rain and heavy metals increased SOD, APX and GPX activities in leaves and GR activity in roots. However, the effects of mixed pollutants on enzyme activities usually were less than the summed effects of individual pollutants. Enzyme responses also depended on where pollutants were applied: spraying pollutants onto the shoots initiated higher responses in SOD, APX and GPX than did application to the soil surface, while the opposite was true for GR.

  3. Antioxidant status and oxidative stress at rest and in response to acute exercise in judokas and sedentary men.

    PubMed

    El Abed, Kaïs; Rebai, Haitham; Bloomer, Richard J; Trabelsi, Khaled; Masmoudi, Liwa; Zbidi, Abdelkarim; Sahnoun, Zouhaier; Hakim, Ahmed; Tabka, Zouhaier

    2011-09-01

    It is well recognized that acute strenuous exercise is accompanied by an increase in free-radical production and subsequent oxidative stress, in addition to changes in blood antioxidant status. Chronic exercise provides protection against exercise-induced oxidative stress by upregulating endogenous antioxidant defense systems. Little is known regarding the protective effect afforded by judo exercise. Therefore, we determined antioxidant and oxidative stress biomarkers at rest and in response to acute exercise in 10 competitive judokas and 10 sedentary subjects after mixed exercise (anaerobic followed by aerobic). The subjects performed a Wingate test, followed by 30 minutes of aerobic exercise performed at 60% of maximal aerobic power. Blood samples were taken, by an intravenous catheter, at rest (R), immediately after the physical exercise (P0), and at 5 (P5), 10 (P10), and 20 (P20) minutes postexercise. The measured parameters included the activity of the antioxidant enzymes superoxide dismutase, glutathione peroxidase, and glutathione reductase, in addition to α-tocopherol, and total antioxidant status. Malondialdehyde was measured as a representation of lipid peroxidation. At rest, the judokas had higher values for all antioxidant and oxidative stress markers as compared to the sedentary subjects (p < 0.05). Plasma concentrations of all parameters except for α-tocopherol increased significantly above resting values for both the judokas and sedentary subjects (p < 0.05) and remained elevated at 20 minutes postexercise. A significant postexercise decrease was observed for α-tocopherol (p < 0.05) at P20 for judokas and at P5 for sedentary subjects. These data indicate that competitive judo athletes have higher endogenous antioxidant protection compared to sedentary subjects. However, both groups of subjects experience an increase in exercise-induced oxidative stress that is not different. PMID:21869626

  4. Arbuscular mycorrhizal fungi alleviate oxidative stress induced by ADOR and enhance antioxidant responses of tomato plants.

    PubMed

    García-Sánchez, Mercedes; Palma, José Manuel; Ocampo, Juan Antonio; García-Romera, Inmaculada; Aranda, Elisabet

    2014-03-15

    The behaviour of tomato plants inoculated with arbuscular mycorrhizal (AM) fungi grown in the presence of aqueous extracts from dry olive residue (ADOR) was studied in order to understand how this symbiotic relationship helps plants to cope with oxidative stress caused by ADOR. The influence of AM symbiosis on plant growth and other physiological parameters was also studied. Tomato plants were inoculated with the AM fungus Funneliformis mosseae and were grown in the presence of ADOR bioremediated and non-bioremediated by Coriolopsis floccosa and Penicillium chrysogenum-10. The antioxidant response as well as parameters of oxidative damage were examined in roots and leaves. The data showed a significant increase in the biomass of AM plant growth in the presence of ADOR, regardless of whether it was bioremediated. The establishment and development of the symbiosis were negatively affected after plants were exposed to ADOR. No differences were observed in the relative water content (RWC) or PS II efficiency between non-AM and AM plants. The increase in the enzymatic activities of superoxide dismutase (SOD; EC 1.15.1.1), catalase (CAT; EC 1.11.1.6) and glutathione-S-transferase (GST; EC 2.5.1.18) were simultaneous to the reduction of MDA levels and H2O2 content in AM root growth in the presence of ADOR. Similar H2O2 levels were observed among non-AM and AM plants, although only AM plants showed reduced lipid peroxidation content, probably due to the involvement of antioxidant enzymes. The results highlight how the application of both bioremediated ADOR and AM fungi can alleviate the oxidative stress conditions, improving the growth and development of tomato plants.

  5. Optimization protocol for the extraction of antioxidant components from Origanum vulgare leaves using response surface methodology

    PubMed Central

    Majeed, Mudasir; Hussain, Abdullah I.; Chatha, Shahzad A.S.; Khosa, Muhammad K.K.; Kamal, Ghulam Mustafa; Kamal, Mohammad A.; Zhang, Xu; Liu, Maili

    2015-01-01

    In the present work, the response surface methodology (RSM) based on a central composite rotatable design (CCRD), was used to determine optimum conditions for the extraction of antioxidant compounds from Origanum vulgare leaves. Four process variables were evaluated at three levels (31 experimental designs): methanol (70%, 80%, and 90%), the solute:solvent ratio (1:5, 1:12.5, 1:20), the extraction time (4, 10, 16 h), and the solute particle size (20, 65, 110 micron). Using RSM, a quadratic polynomial equation was obtained by multiple regression analysis for predicting optimization of the extraction protocol. Analysis of variance (ANOVA) was applied and the significant effect of the factors and their interactions were tested at 95% confidence interval. The antioxidant extract (AE) yield was significantly influenced by solvent composition, solute to solvent ratio, and time. The maximum AE was obtained at methanol (70%), liquid solid ratio (20), time (16 h), and particle size (20 micron). Predicted values thus obtained were closer to the experimental value indicating suitability of the model. Run 25 (methanol:water 70:30; solute:solvent 1:20; extraction time 16 h and solute particle size 20) showed highest TP contents (18.75 mg/g of dry material, measured as gallic acid equivalents) and DPPH radical scavenging activity (IC50 5.04 μg/mL). Results of the present study indicated good correlation between TP contents and DPPH radical scavenging activity. Results of the study indicated that phenolic compounds are powerful scavengers of free radical as demonstrated by a good correlation between TP contents and DPPH radical scavenging activity. PMID:27081365

  6. Salicylic acid induces differential antioxidant response in spring maize under high temperature stress.

    PubMed

    Khanna, Palak; Kaur, Kamaljit; Gupta, Anil K

    2016-06-01

    High temperature is one of the important stress factors that affect crops in tropical countries. Plants do evolve or adopt different mechanisms to overcome such stress for survival. It is an interesting subject and has attracted many researchers to work upon. Here, we studied the effect of salicylic acid (SA) on seedling growth and antioxidative defense system in two spring maize (Zea mays L.) genotypes viz., CML-32 (relatively heat tolerant) and LM-11 (relatively heat susceptible), under high temperature stress. High temperature induced greater reduction in dry biomass of LM-1 1 seedlings as compared to those of CML-32. There was a parallel increase in ascorbate peroxidase and glutathione reductase activities in the roots of CML-32 seedlings. However, the activities of catalase and superoxide dismutase decreased and the contents of H202, proline and malonaldialdehyde (MDA) increased in seedlings of both the genotypes. Application of SA (400 µM) led to increased dry biomass in heat stressed CML-32 seedlings. It improved the efficiency of Halliwell-Asada pathway in roots of CML-32 seedlings as was evidenced by the enhanced ascorbate peroxidase and glutathione reductase activities. The activities of catalase and superoxide dismutase increased in both the tissues of LM-11 seedlings, whereas in CML-32, it was only in shoots, after SA application. Peroxidase activity increased in SA treated seedlings of both the genotypes, though the increase was comparatively higher in CML-32. The contents of H₂O₂ and MDA decreased and that of proline increased in SA treated seedlings of both the genotypes, under stress conditions. It may be concluded that SA induced differential antioxidant response by upregulating Halliwell-Asada pathway in roots and attaining high POX activity in both the tissues of CML-32 seedlings, under high temperature stress.

  7. Enzymatic and non-enzymatic antioxidant responses of alfalfa leaves and roots under different salinity levels.

    PubMed

    Dehghan, G; Amjad, Leyla; Nosrati, H

    2013-06-01

    The effect of increasing NaCl concentrations on biomass, hydrogen peroxide (H2O2), ascorbic acid (ASC), proline and total thiol, and the activity of some antioxidant enzymes in alfalfa (Medicago sativa L. cv. Gara-Yonjeh) were investigated. The dry weights of roots and shoots with increasing NaCl concentrations decreased progressively, and the strongest toxicity was detected at NaCl treatment of 200 mM. Superoxide dismutase (SOD) activity in the leaves increased gradually up to NaCl concentrations of 100, while the higher concentration of NaCl reduced SOD activity in both leaves and roots. The maximum levels of ascorbate peroxidase (APX) activity were increased at 150 mM and 100 mM NaCl in leaves and roots of Gara-Yonjeh, respectively. Peroxidase (POD) activity in roots of Gara-Yonjeh increased (82% at 200 mM) by salinity, while it decreased (43% at 200 mM) in leaves. In contrast, catalase (CAT) activity increased (84% at 200 mM) in leaves, and decreased (57% at 200 mM) in the roots of Gara-Yonjeh. Electrophoresis analysis suggested that different patterns in SOD, CAT and POD isoenzymes depend on NaCl concentrations, and the staining intensities of these isoforms are supported the results obtained from the spectrophotometric determinations. In POD and CAT, activity of isoform III was detected at all concentrations, by a "low-high-low" pattern, with the maximum activity at 50 mM of NaCl. Results imply that the function of antioxidant systems in higher NaCl concentration is responsible for the salt tolerance observed in Gara-Yonjeh. PMID:23739889

  8. Salicylic acid induces differential antioxidant response in spring maize under high temperature stress.

    PubMed

    Khanna, Palak; Kaur, Kamaljit; Gupta, Anil K

    2016-06-01

    High temperature is one of the important stress factors that affect crops in tropical countries. Plants do evolve or adopt different mechanisms to overcome such stress for survival. It is an interesting subject and has attracted many researchers to work upon. Here, we studied the effect of salicylic acid (SA) on seedling growth and antioxidative defense system in two spring maize (Zea mays L.) genotypes viz., CML-32 (relatively heat tolerant) and LM-11 (relatively heat susceptible), under high temperature stress. High temperature induced greater reduction in dry biomass of LM-1 1 seedlings as compared to those of CML-32. There was a parallel increase in ascorbate peroxidase and glutathione reductase activities in the roots of CML-32 seedlings. However, the activities of catalase and superoxide dismutase decreased and the contents of H202, proline and malonaldialdehyde (MDA) increased in seedlings of both the genotypes. Application of SA (400 µM) led to increased dry biomass in heat stressed CML-32 seedlings. It improved the efficiency of Halliwell-Asada pathway in roots of CML-32 seedlings as was evidenced by the enhanced ascorbate peroxidase and glutathione reductase activities. The activities of catalase and superoxide dismutase increased in both the tissues of LM-11 seedlings, whereas in CML-32, it was only in shoots, after SA application. Peroxidase activity increased in SA treated seedlings of both the genotypes, though the increase was comparatively higher in CML-32. The contents of H₂O₂ and MDA decreased and that of proline increased in SA treated seedlings of both the genotypes, under stress conditions. It may be concluded that SA induced differential antioxidant response by upregulating Halliwell-Asada pathway in roots and attaining high POX activity in both the tissues of CML-32 seedlings, under high temperature stress. PMID:27468465

  9. Optimization protocol for the extraction of antioxidant components from Origanum vulgare leaves using response surface methodology.

    PubMed

    Majeed, Mudasir; Hussain, Abdullah I; Chatha, Shahzad A S; Khosa, Muhammad K K; Kamal, Ghulam Mustafa; Kamal, Mohammad A; Zhang, Xu; Liu, Maili

    2016-05-01

    In the present work, the response surface methodology (RSM) based on a central composite rotatable design (CCRD), was used to determine optimum conditions for the extraction of antioxidant compounds from Origanum vulgare leaves. Four process variables were evaluated at three levels (31 experimental designs): methanol (70%, 80%, and 90%), the solute:solvent ratio (1:5, 1:12.5, 1:20), the extraction time (4, 10, 16 h), and the solute particle size (20, 65, 110 micron). Using RSM, a quadratic polynomial equation was obtained by multiple regression analysis for predicting optimization of the extraction protocol. Analysis of variance (ANOVA) was applied and the significant effect of the factors and their interactions were tested at 95% confidence interval. The antioxidant extract (AE) yield was significantly influenced by solvent composition, solute to solvent ratio, and time. The maximum AE was obtained at methanol (70%), liquid solid ratio (20), time (16 h), and particle size (20 micron). Predicted values thus obtained were closer to the experimental value indicating suitability of the model. Run 25 (methanol:water 70:30; solute:solvent 1:20; extraction time 16 h and solute particle size 20) showed highest TP contents (18.75 mg/g of dry material, measured as gallic acid equivalents) and DPPH radical scavenging activity (IC50 5.04 μg/mL). Results of the present study indicated good correlation between TP contents and DPPH radical scavenging activity. Results of the study indicated that phenolic compounds are powerful scavengers of free radical as demonstrated by a good correlation between TP contents and DPPH radical scavenging activity. PMID:27081365

  10. Arbuscular mycorrhizal fungi alleviate oxidative stress induced by ADOR and enhance antioxidant responses of tomato plants.

    PubMed

    García-Sánchez, Mercedes; Palma, José Manuel; Ocampo, Juan Antonio; García-Romera, Inmaculada; Aranda, Elisabet

    2014-03-15

    The behaviour of tomato plants inoculated with arbuscular mycorrhizal (AM) fungi grown in the presence of aqueous extracts from dry olive residue (ADOR) was studied in order to understand how this symbiotic relationship helps plants to cope with oxidative stress caused by ADOR. The influence of AM symbiosis on plant growth and other physiological parameters was also studied. Tomato plants were inoculated with the AM fungus Funneliformis mosseae and were grown in the presence of ADOR bioremediated and non-bioremediated by Coriolopsis floccosa and Penicillium chrysogenum-10. The antioxidant response as well as parameters of oxidative damage were examined in roots and leaves. The data showed a significant increase in the biomass of AM plant growth in the presence of ADOR, regardless of whether it was bioremediated. The establishment and development of the symbiosis were negatively affected after plants were exposed to ADOR. No differences were observed in the relative water content (RWC) or PS II efficiency between non-AM and AM plants. The increase in the enzymatic activities of superoxide dismutase (SOD; EC 1.15.1.1), catalase (CAT; EC 1.11.1.6) and glutathione-S-transferase (GST; EC 2.5.1.18) were simultaneous to the reduction of MDA levels and H2O2 content in AM root growth in the presence of ADOR. Similar H2O2 levels were observed among non-AM and AM plants, although only AM plants showed reduced lipid peroxidation content, probably due to the involvement of antioxidant enzymes. The results highlight how the application of both bioremediated ADOR and AM fungi can alleviate the oxidative stress conditions, improving the growth and development of tomato plants. PMID:24594394

  11. Increased antioxidant response and capability to produce ROS in hemocytes of Pinna nobilis L. exposed to anthropogenic activity.

    PubMed

    Sureda, Antoni; Natalotto, Antonino; Alvarez, Elvira; Deudero, Salud

    2013-10-01

    Environmental pollutants exert immunotoxical effects on aquatic organisms. The aim was to determine the antioxidant response, markers of oxidative damage and reactive oxygen species production in hemocytes of Pinna nobilis, the largest endemic bivalve in the Mediterranean Sea, under anthropogenic pressure. P. nobilis individuals were collected from two locations along Mallorca Island waters attending to different degree of human impact and the hemocytes were obtained. Specimens from the impacted area showed increased activities of the antioxidant enzymes - catalase, superoxide dismutase, glutathione peroxidase and glutathione reductase -, myeloperoxidase activity and reduced glutathione levels. No differences in oxidative damage markers - malondiahdehyde and carbonyl index - were evidenced between the pristine and polluted areas. Hemocytes from the polluted area presented increased capability to generate reactive oxygen species and nitrite/nitrate when activated. In conclusion, the human activities primed hemocytes for oxidative burst and increased the antioxidant mechanism without evidence of oxidative damage. PMID:23871388

  12. Optimization of ultrasonic-assisted extraction of antioxidant compounds from Guava (Psidium guajava L.) leaves using response surface methodology

    PubMed Central

    Kong, Fansheng; Yu, Shujuan; Feng, Zeng; Wu, Xinlan

    2015-01-01

    Objective: To optimization of extraction of antioxidant compounds from guava (Psidium guajava L.) leaves and showed that the guava leaves are the potential source of antioxidant compounds. Materials and Methods: The bioactive polysaccharide compounds of guava leaves (P. guajava L.) were obtained using ultrasonic-assisted extraction. Extraction was carried out according to Box-Behnken central composite design, and independent variables were temperature (20–60°C), time (20–40 min) and power (200–350 W). The extraction process was optimized by using response surface methodology for the highest crude extraction yield of bioactive polysaccharide compounds. Results: The optimal conditions were identified as 55°C, 30 min, and 240 W. 1,1-diphenyl-2-picryl-hydrazyl and hydroxyl free radical scavenging were conducted. Conclusion: The results of quantification showed that the guava leaves are the potential source of antioxidant compounds. PMID:26246720

  13. Antioxidant responses in soybean and alfalfa plants grown in DDTs contaminated soils: Useful variables for selecting plants for soil phytoremediation?

    PubMed

    Mitton, Francesca M; Ribas Ferreira, Josencler L; Gonzalez, Mariana; Miglioranza, Karina S B; Monserrat, José M

    2016-06-01

    Phytoremediation is a low-cost alternative technology based on the use of plants to remove pollutants from the environment. Persistent organic pollutants such as DDTs with a long half-life in soils are attractive candidates for remediation. This study aimed to determine the potential of antioxidant response use in the evaluation of plants' tolerance for selecting species in phytoremediation purposes. Alfalfa and soybean plants were grown in DDT contaminated soils. After 60days, growth, protein content, antioxidant capacity, GST activity, concentration of proteic and non-proteic thiol groups, chlorophyll content and carotenoid content were measured in plant tissues. Results showed no effect on alfalfa or soybean photosynthetic pigments but different responses in the protein content, antioxidant capacity, GST activity and thiol groups on roots, stems and leaves, indicating that DDTs affected both species. Soybean showed higher susceptibility than alfalfa plants due to the lower antioxidant capacity and GST activity in leaves, in spite of having the lowest DDT accumulation. This study provides new insights into the role of oxidative stress as an important component of the plant's response to DDT exposure.

  14. Antioxidant responses in soybean and alfalfa plants grown in DDTs contaminated soils: Useful variables for selecting plants for soil phytoremediation?

    PubMed

    Mitton, Francesca M; Ribas Ferreira, Josencler L; Gonzalez, Mariana; Miglioranza, Karina S B; Monserrat, José M

    2016-06-01

    Phytoremediation is a low-cost alternative technology based on the use of plants to remove pollutants from the environment. Persistent organic pollutants such as DDTs with a long half-life in soils are attractive candidates for remediation. This study aimed to determine the potential of antioxidant response use in the evaluation of plants' tolerance for selecting species in phytoremediation purposes. Alfalfa and soybean plants were grown in DDT contaminated soils. After 60days, growth, protein content, antioxidant capacity, GST activity, concentration of proteic and non-proteic thiol groups, chlorophyll content and carotenoid content were measured in plant tissues. Results showed no effect on alfalfa or soybean photosynthetic pigments but different responses in the protein content, antioxidant capacity, GST activity and thiol groups on roots, stems and leaves, indicating that DDTs affected both species. Soybean showed higher susceptibility than alfalfa plants due to the lower antioxidant capacity and GST activity in leaves, in spite of having the lowest DDT accumulation. This study provides new insights into the role of oxidative stress as an important component of the plant's response to DDT exposure. PMID:27155479

  15. Antioxidant responses of citrus red mite, Panonychus citri (McGregor) (Acari: Tetranychidae), exposed to thermal stress.

    PubMed

    Yang, Li-Hong; Huang, Hai; Wang, Jin-Jun

    2010-12-01

    Relatively low or high temperatures are responsible for a variety of physiological stress responses in insects and mites. Induced thermal stress was recently associated with increased reactive oxygen species (ROS) generation, which caused oxidative damage. In this study, we examined the time-related effect of the relatively low (0, 5, 10, and 15 °C) or high (32, 35, 38, and 41 °C) temperatures on the activities of antioxidant enzymes including superoxide dismutase (SOD), catalase (CAT), peroxidases (POX), and glutathione-S-transferase (GST), and the total antioxidant capacity (TEAC) of the citrus red mite, Panonychus citri (McGregor). The malondialdehyde (MDA) concentration, as a marker of lipid peroxidation in organisms, was also measured in the citrus red mite under thermal stress conditions. Results showed that SOD and GST activities were significantly increased and play an important role in the process of antioxidant response to thermal stress. Lipid peroxidation levels increased significantly (P<0.001) and changed in a time-dependent manner. CAT and POX activity, as well as TEAC, did not vary significantly and play a minor role to remove the ROS generation. These results suggest that thermal stress leads to oxidative stress and antioxidant enzymes play an important role in reducing oxidative damage in the citrus red mite. PMID:20709071

  16. Optimization of Ultrasound-Assisted Extraction of Natural Antioxidants from the Flower of Jatropha integerrima by Response Surface Methodology.

    PubMed

    Xu, Dong-Ping; Zhou, Yue; Zheng, Jie; Li, Sha; Li, An-Na; Li, Hua-Bin

    2015-12-24

    An ultrasound-assisted extraction (UAE) method was developed for the efficient extraction of natural antioxidants from the flowers of Jatropha integerrima. Four independent variables, including ethanol concentration, solvent/material ratio, ultrasound irradiation time and temperature were studied by single factor experiments. Then, the central composite rotatable design and response surface methodology were employed to investigate the effect of three key parameters (ethanol concentration, solvent/material ratio, and ultrasound irradiation time) on the antioxidant activities of the flower extracts. The optimal extraction conditions were an ethanol concentration of 59.6%, solvent/material ratio of 50:1, ultrasound irradiation time of 7 min, and ultrasound irradiation temperature of 40 °C. Under these conditions, the optimized experimental value was 1103.38 ± 16.11 µmol Trolox/g dry weight (DW), which was in accordance with the predicted value (1105.49 µmol Trolox/g DW). Furthermore, the antioxidant activities of flower extracts obtained by UAE were compared with those produced by the traditional maceration and Soxhlet extraction methods, and UAE resulted in higher antioxidant activities after a shorter time at a lower temperature. The results obtained are helpful for the full utilization of Jatropha integerrima, and also indicate that ultrasound-assisted extraction is an efficient method for the extraction of natural antioxidants from plant materials.

  17. Optimization of Ultrasound-Assisted Extraction of Natural Antioxidants from the Flower of Jatropha integerrima by Response Surface Methodology.

    PubMed

    Xu, Dong-Ping; Zhou, Yue; Zheng, Jie; Li, Sha; Li, An-Na; Li, Hua-Bin

    2015-01-01

    An ultrasound-assisted extraction (UAE) method was developed for the efficient extraction of natural antioxidants from the flowers of Jatropha integerrima. Four independent variables, including ethanol concentration, solvent/material ratio, ultrasound irradiation time and temperature were studied by single factor experiments. Then, the central composite rotatable design and response surface methodology were employed to investigate the effect of three key parameters (ethanol concentration, solvent/material ratio, and ultrasound irradiation time) on the antioxidant activities of the flower extracts. The optimal extraction conditions were an ethanol concentration of 59.6%, solvent/material ratio of 50:1, ultrasound irradiation time of 7 min, and ultrasound irradiation temperature of 40 °C. Under these conditions, the optimized experimental value was 1103.38 ± 16.11 µmol Trolox/g dry weight (DW), which was in accordance with the predicted value (1105.49 µmol Trolox/g DW). Furthermore, the antioxidant activities of flower extracts obtained by UAE were compared with those produced by the traditional maceration and Soxhlet extraction methods, and UAE resulted in higher antioxidant activities after a shorter time at a lower temperature. The results obtained are helpful for the full utilization of Jatropha integerrima, and also indicate that ultrasound-assisted extraction is an efficient method for the extraction of natural antioxidants from plant materials. PMID:26712723

  18. In vitro antioxidant profiling of seabuckthorn varieties and their adaptogenic response to high altitude-induced stress

    NASA Astrophysics Data System (ADS)

    Sharma, Priyanka; Suryakumar, Geetha; Singh, Virendra; Misra, Kshipra; Singh, Shashi Bala

    2015-08-01

    In the past few years, seabuckthorn plants have gained special attention due to their ability to grow in the harshest of the environment. This adaptability may be contributed by various antioxidants present in the plants besides other morphological adaptation. As in vivo studies cannot be justified without in vitro studies, the present investigation carried out evaluation of both in vitro and in vivo antioxidant potentials of aqueous and alcoholic extracts of the leaves of Hippophae salicifolia (HS) and Hippophae rhamnoides mongolica (HRM) in comparison with Hippophae rhamnoides turkestanica (HRT). The results had clearly depicted that in vitro antioxidant potential of the extracts was responsible for the in vivo adaptogenic performance in animals during cold and hypoxia exposure under restraint stress. Total phenolic content (TPC), total flavonoid content (TFC), total protein content, and antioxidant potential were determined. For adaptogenic studies, rats with oral drug supplementation were exposed to Cold-hypoxia-restraint (C-H-R) stresses-induced hypothermia, as a measure of endurance. Aqueous extracts of HS showed maximum (99 %) resistance compared to HRT (81 %) and HRM (29 %). The levels of biochemical parameters such as malondialdehyde (MDA), reactive oxygen species (ROS), lactate dehydrogenase (LDH), superoxide dismutase (SOD), glutathione (GSH/GSSG), and catalase (CAT) in blood samples also revealed that the aqueous leaf extract of HS has better antioxidant and adaptogenic potential compared to HRM.

  19. In vitro antioxidant profiling of seabuckthorn varieties and their adaptogenic response to high altitude-induced stress.

    PubMed

    Sharma, Priyanka; Suryakumar, Geetha; Singh, Virendra; Misra, Kshipra; Singh, Shashi Bala

    2015-08-01

    In the past few years, seabuckthorn plants have gained special attention due to their ability to grow in the harshest of the environment. This adaptability may be contributed by various antioxidants present in the plants besides other morphological adaptation. As in vivo studies cannot be justified without in vitro studies, the present investigation carried out evaluation of both in vitro and in vivo antioxidant potentials of aqueous and alcoholic extracts of the leaves of Hippophae salicifolia (HS) and Hippophae rhamnoides mongolica (HRM) in comparison with Hippophae rhamnoides turkestanica (HRT). The results had clearly depicted that in vitro antioxidant potential of the extracts was responsible for the in vivo adaptogenic performance in animals during cold and hypoxia exposure under restraint stress. Total phenolic content (TPC), total flavonoid content (TFC), total protein content, and antioxidant potential were determined. For adaptogenic studies, rats with oral drug supplementation were exposed to Cold-hypoxia-restraint (C-H-R) stresses-induced hypothermia, as a measure of endurance. Aqueous extracts of HS showed maximum (99 %) resistance compared to HRT (81 %) and HRM (29 %). The levels of biochemical parameters such as malondialdehyde (MDA), reactive oxygen species (ROS), lactate dehydrogenase (LDH), superoxide dismutase (SOD), glutathione (GSH/GSSG), and catalase (CAT) in blood samples also revealed that the aqueous leaf extract of HS has better antioxidant and adaptogenic potential compared to HRM. PMID:25384585

  20. Lettuce irrigated with contaminated water: Photosynthetic effects, antioxidative response and bioaccumulation of microcystin congeners.

    PubMed

    Bittencourt-Oliveira, Maria do Carmo; Cordeiro-Araújo, Micheline Kézia; Chia, Mathias Ahii; Arruda-Neto, João Dias de Toledo; de Oliveira, Ênio Tiago; dos Santos, Flávio

    2016-06-01

    The use of microcystins (MCs) contaminated water to irrigate crop plants represents a human health risk due to their bioaccumulation potential. In addition, MCs cause oxidative stress and negatively influence photosynthetic activities in plants. The present study was aimed at investigating the effect of MCs on photosynthetic parameters and antioxidative response of lettuce. Furthermore, the bioaccumulation factor (BAF) of total MCs, MC-LR and MC-RR in the vegetable after irrigation with contaminated water was determined. Lettuce crops were irrigated for 15 days with water containing cyanobacterial crude extracts (Microcystis aeruginosa) with MC-LR (0.0, 0.5, 2.0, 5.0 and 10.0 µg L(-1)), MC-RR (0.0, 0.15, 0.5, 1.5 and 3.0 µg L(-1)) and total MCs (0.0, 0.65, 2.5, 6.5 and 13.0 µg L(-1)). Increased net photosynthetic rate, stomatal conductance, leaf tissue transpiration and intercellular CO2 concentration were recorded in lettuce exposed to different MCs concentrations. Antioxidant response showed that glutathione S-transferase activity was down-regulated in the presence of MCs. On the other hand, superoxide dismutase, catalase and peroxidase activities were upregulated with increasing MCs concentrations. The bioaccumulation factor (BAF) of total MCs and MC-LR was highest at 6.50 and 5.00 µg L(-1), respectively, while for MC-RR, the highest BAF was recorded at 1.50 µg L(-1) concentration. The amount of total MCs, MC-LR and MC-RR bioacumulated in lettuce was highest at the highest exposure concentrations. However, at the lowest exposure concentration, there were no detectable levels of MC-LR, MC-RR and total MCs in lettuce. Thus, the bioaccumulation of MCs in lettuce varies according to the exposure concentration. In addition, the extent of physiological response of lettuce to the toxins relies on exposure concentrations. PMID:26896895

  1. Physiological and biochemical responses of Suaeda fruticosa to cadmium and copper stresses: growth, nutrient uptake, antioxidant enzymes, phytochelatin, and glutathione levels.

    PubMed

    Bankaji, I; Caçador, I; Sleimi, N

    2015-09-01

    Environmental pollution by trace metal elements (TMEs) is a serious problem worldwide, increasing in parallel with the development of human technology. The present research aimed to examine the response of halophytic species Suaeda fruticosa to oxidative stress posed by combined abiotic stresses. Plants have been grown for 1 month with an irrigation solution supplemented with 200 mM NaCl and 400 μM Cd(2+) or 400 μM Cu(2+). The level of glutathione (GSH), phytochelatins (PCs), and antioxidant enzyme activities [ascorbate peroxidase (APX), guaiacol peroxidase (GPX), and catalase (CAT)] as well as lipid peroxidation was studied to see the stress exerted by the TME and the level of tolerance and detoxification strategy adopted by S. fruticosa. Relative growth rate (RGR) decreased under Cd(2+) stress in this species, whereas Cu(2+) did not have any impact on S. fruticosa performance. Cd(2+) or Cu(2+) enhanced malondialdehyde, suggesting reactive oxygen species-induced disruption of membrane integrity and oxidative stress in S. fruticosa. On the other hand, the activities of the antioxidant enzymes CAT, APX, and GPX diminished and mineral nutrition was disturbed by metal stress. S. fruticosa was able to synthesize PCs in response to TME toxicity. However, data indicate that GSH levels underwent a significant decrease in roots and leaves of S. fruticosa stressed by Cd(2+) or Cu(2+). The GSH depletion accompanied by the increase of phytochelatin concentration suggests the involvement of GSH in the synthesis of phytochelatins. PMID:25925143

  2. Physiological and biochemical responses of Suaeda fruticosa to cadmium and copper stresses: growth, nutrient uptake, antioxidant enzymes, phytochelatin, and glutathione levels.

    PubMed

    Bankaji, I; Caçador, I; Sleimi, N

    2015-09-01

    Environmental pollution by trace metal elements (TMEs) is a serious problem worldwide, increasing in parallel with the development of human technology. The present research aimed to examine the response of halophytic species Suaeda fruticosa to oxidative stress posed by combined abiotic stresses. Plants have been grown for 1 month with an irrigation solution supplemented with 200 mM NaCl and 400 μM Cd(2+) or 400 μM Cu(2+). The level of glutathione (GSH), phytochelatins (PCs), and antioxidant enzyme activities [ascorbate peroxidase (APX), guaiacol peroxidase (GPX), and catalase (CAT)] as well as lipid peroxidation was studied to see the stress exerted by the TME and the level of tolerance and detoxification strategy adopted by S. fruticosa. Relative growth rate (RGR) decreased under Cd(2+) stress in this species, whereas Cu(2+) did not have any impact on S. fruticosa performance. Cd(2+) or Cu(2+) enhanced malondialdehyde, suggesting reactive oxygen species-induced disruption of membrane integrity and oxidative stress in S. fruticosa. On the other hand, the activities of the antioxidant enzymes CAT, APX, and GPX diminished and mineral nutrition was disturbed by metal stress. S. fruticosa was able to synthesize PCs in response to TME toxicity. However, data indicate that GSH levels underwent a significant decrease in roots and leaves of S. fruticosa stressed by Cd(2+) or Cu(2+). The GSH depletion accompanied by the increase of phytochelatin concentration suggests the involvement of GSH in the synthesis of phytochelatins.

  3. Antioxidant response to natural organic matter (NOM) exposure in three Baikalean amphipod species from contrasting habitats.

    PubMed

    Timofeyev, M A; Steinberg, C E W

    2006-10-01

    The aim of the present work is to comparatively evaluate the oxidative stress response on exposure to natural organic matter (NOM) in three amphipod (Crustacea, Amphipoda) species from different taxonomic groups and different habitats of Lake Baikal. Endemic species from Lake Baikal were used: the shallow-water dwelling Gmelinoides fasciatus (Dyb.), Pallasea cancelloides (Gerstf.), and the deep-layer inhabitant Ommatogammarus flavus (Dyb.). Three key enzymes, catalase (CAT), peroxidase (POD), and glutathione S-transferase (GST), were studied. The applied NOM from Lake Schwarzer (Germany) directly impacts the two littoral species which quickly respond. The response is characterized by a significant decrease of POD and an increase of CAT activities. GST activity remains stable or decreased slightly. In contrast to the littoral amphipods, the deep-layer inhabitant O. flavus showed no significant reaction to NOM exposure, probably due to decreased adaptive ability of this species. The stable environment of the Baikalean deep zones obviously does not provide triggers for the development of flexible antioxidant or general defense systems. PMID:16914340

  4. H2O2-responsive antioxidant polymeric nanoparticles as therapeutic agents for peripheral arterial disease.

    PubMed

    Kwon, Byeongsu; Kang, Changsun; Kim, Jinsub; Yoo, Donghyuck; Cho, Byung-Ryul; Kang, Peter M; Lee, Dongwon

    2016-09-25

    Peripheral artery disease (PAD) is a common circulatory disorder in which narrowed arteries limit blood flow to the lower extremity and affect millions of people worldwide. Therapeutic angiogenesis has emerged as a promising strategy to treat PAD patients because surgical intervention has been showing limited success. Leg muscles of PAD patients have significantly high level of ROS (reactive oxygen species) and the increased production of ROS is a key mechanism of initiation and progression of PAD. We have recently developed H2O2-responsive polymer PVAX, which is designed to rapidly scavenge H2O2 and release vanillyl alcohol with antioxidant and anti-inflammatory activity. In this study, we investigated the therapeutic efficacy of PVAX nanoparticles for PAD using a cell culture model and a mouse model of hindlimb ischemia. PVAX nanoparticles significantly enhanced the expression of angiogenic inducers such as vascular endothelial growth factor (VEGF) and platelet endothelial cell adhesion molecule (PECAM)-1 in human umbilical vein endothelial cells (HUVEC). PVAX nanoparticles promoted revascularization and restoration of blood perfusion into ischemic tissues by upregulating angiogenic VEGF and PECAM-1. This work demonstrates that H2O2-responsive PVAX nanoparticles facilitate therapeutic angiogenesis and hold tremendous translational potential as therapeutic systems for ischemic diseases such as PAD. PMID:27521705

  5. Preventive antioxidant responses to extreme oxygen level fluctuation in a subterranean crustacean.

    PubMed

    Lawniczak, M; Romestaing, C; Roussel, D; Maazouzi, C; Renault, D; Hervant, F

    2013-06-01

    The principal aim of this work was to explore the responses of the groundwater crustacean Niphargus rhenorhodanensis to oxidative stress caused by short- and long-term drastic variations in oxygen level. To this end, we investigated thiobarbituric acid reactive substances (TBARS) levels and anti-oxidative enzyme (SOD and GPx) activities during 24 h anoxia and post-anoxia recovery, and during 10 days of severe hypoxia and post-hypoxia recovery. We observed a decrease in TBARS amounts during recovery from severe hypoxia. Parallel to these results, we observed an overactivation of SOD activity after a 24 h anoxic stress. GPx activity measured at the end of anoxia or severe hypoxia and in the early hours of post-stress recovery also showed an overactivation compared to the control group. We can hypothesize that this overproduction of GPx corresponded to an anticipatory mechanism coping with the overproduction of reactive oxygen species (ROS) during the recovery phase in subterranean animals. This response could be considered as a major asset for life in alternately normoxic and hypoxic conditions, and therefore in extreme biotopes such as groundwaters.

  6. Morinda citrifolia leaf enhanced performance by improving angiogenesis, mitochondrial biogenesis, antioxidant, anti-inflammatory & stress responses.

    PubMed

    Mohamad Shalan, Nor Aijratul Asikin; Mustapha, Noordin M; Mohamed, Suhaila

    2016-12-01

    Morinda citrifolia fruit, (noni), enhanced performances in athletes and post-menopausal women in clinical studies. This report shows the edible noni leaves water extract enhances performance in a weight-loaded swimming animal model better than the fruit or standardized green tea extract. The 4weeks study showed the extract (containing scopoletin and epicatechin) progressively prolonged the time to exhaustion by threefold longer than the control, fruit or tea extract. The extract improved (i) the mammalian antioxidant responses (MDA, GSH and SOD2 levels), (ii) tissue nutrient (glucose) and metabolite (lactate) management, (iii) stress hormone (cortisol) regulation; (iv) neurotransmitter (dopamine, noradrenaline, serotonin) expressions, transporter or receptor levels, (v) anti-inflammatory (IL4 & IL10) responses; (v) skeletal muscle angiogenesis (VEGFA) and (v) energy and mitochondrial biogenesis (via PGC, UCP3, NRF2, AMPK, MAPK1, and CAMK4). The ergogenic extract helped delay fatigue by enhancing energy production, regulation and efficiency, which suggests benefits for physical activities and disease recovery. PMID:27374554

  7. Acute phase protein and antioxidant responses in dogs with experimental acute monocytic ehrlichiosis treated with rifampicin.

    PubMed

    Karnezi, Dimitra; Ceron, Jose J; Theodorou, Konstantina; Leontides, Leonidas; Siarkou, Victoria I; Martinez, Silvia; Tvarijonaviciute, Asta; Harrus, Shimon; Koutinas, Christos K; Pardali, Dimitra; Mylonakis, Mathios E

    2016-02-29

    There is currently lack of information on the changes of acute phase proteins (APP) and antioxidant markers and their clinical relevance as treatment response indicators in canine monocytic ehrlichiosis (CME). The objective of this study was to investigate the patterns of C-reactive protein (CRP), haptoglobin (Hp), ferritin and paraoxonase-1 (PON-1) during treatment of dogs with acute CME with rifampicin. Blood serum samples from ten Beagle dogs with experimental acute CME were retrospectively examined. Five dogs (Group A) were treated with rifampicin (10mg/Kg/24h), per os, for 3 weeks and 5 dogs (Group B) received no treatment (infected controls). Two Beagle dogs served as uninfected controls. Blood serum samples were serially examined prior to Ehrlichia canis inoculation and on post-inoculation days 14, 21, 28, 35 and 42. Significant changes of CRP, Hp, ferritin and PON-1 values were found in the majority of infected dogs. However, their concentrations did not differ between the two groups during the treatment observation period. The results of this study indicate that although several APP and PON-1 tend to significantly change in the majority of dogs with acute CME, they were of limited clinical relevance as treatment response indicators in this experimental setting.

  8. Cysteine Sulfenylation Directs IRE-1 to Activate the SKN-1/Nrf2 Antioxidant Response.

    PubMed

    Hourihan, John M; Moronetti Mazzeo, Lorenza E; Fernández-Cárdenas, L Paulette; Blackwell, T Keith

    2016-08-18

    Emerging evidence suggests that many proteins may be regulated through cysteine modification, but the extent and functions of this signaling remain largely unclear. The endoplasmic reticulum (ER) transmembrane protein IRE-1 maintains ER homeostasis by initiating the unfolded protein response (UPR(ER)). Here we show in C. elegans and human cells that IRE-1 has a distinct redox-regulated function in cytoplasmic homeostasis. Reactive oxygen species (ROS) that are generated at the ER or by mitochondria sulfenylate a cysteine within the IRE-1 kinase activation loop. This inhibits the IRE-1-mediated UPR(ER) and initiates the p38/SKN-1(Nrf2) antioxidant response, thereby increasing stress resistance and lifespan. Many AGC-family kinases (AKT, p70S6K, PKC, ROCK1) seem to be regulated similarly. The data reveal that IRE-1 has an ancient function as a cytoplasmic sentinel that activates p38 and SKN-1(Nrf2) and indicate that cysteine modifications induced by ROS signals can direct proteins to adopt unexpected functions and may coordinate many cellular processes. PMID:27540856

  9. Acute phase protein and antioxidant responses in dogs with experimental acute monocytic ehrlichiosis treated with rifampicin.

    PubMed

    Karnezi, Dimitra; Ceron, Jose J; Theodorou, Konstantina; Leontides, Leonidas; Siarkou, Victoria I; Martinez, Silvia; Tvarijonaviciute, Asta; Harrus, Shimon; Koutinas, Christos K; Pardali, Dimitra; Mylonakis, Mathios E

    2016-02-29

    There is currently lack of information on the changes of acute phase proteins (APP) and antioxidant markers and their clinical relevance as treatment response indicators in canine monocytic ehrlichiosis (CME). The objective of this study was to investigate the patterns of C-reactive protein (CRP), haptoglobin (Hp), ferritin and paraoxonase-1 (PON-1) during treatment of dogs with acute CME with rifampicin. Blood serum samples from ten Beagle dogs with experimental acute CME were retrospectively examined. Five dogs (Group A) were treated with rifampicin (10mg/Kg/24h), per os, for 3 weeks and 5 dogs (Group B) received no treatment (infected controls). Two Beagle dogs served as uninfected controls. Blood serum samples were serially examined prior to Ehrlichia canis inoculation and on post-inoculation days 14, 21, 28, 35 and 42. Significant changes of CRP, Hp, ferritin and PON-1 values were found in the majority of infected dogs. However, their concentrations did not differ between the two groups during the treatment observation period. The results of this study indicate that although several APP and PON-1 tend to significantly change in the majority of dogs with acute CME, they were of limited clinical relevance as treatment response indicators in this experimental setting. PMID:26854345

  10. H2O2-responsive antioxidant polymeric nanoparticles as therapeutic agents for peripheral arterial disease.

    PubMed

    Kwon, Byeongsu; Kang, Changsun; Kim, Jinsub; Yoo, Donghyuck; Cho, Byung-Ryul; Kang, Peter M; Lee, Dongwon

    2016-09-25

    Peripheral artery disease (PAD) is a common circulatory disorder in which narrowed arteries limit blood flow to the lower extremity and affect millions of people worldwide. Therapeutic angiogenesis has emerged as a promising strategy to treat PAD patients because surgical intervention has been showing limited success. Leg muscles of PAD patients have significantly high level of ROS (reactive oxygen species) and the increased production of ROS is a key mechanism of initiation and progression of PAD. We have recently developed H2O2-responsive polymer PVAX, which is designed to rapidly scavenge H2O2 and release vanillyl alcohol with antioxidant and anti-inflammatory activity. In this study, we investigated the therapeutic efficacy of PVAX nanoparticles for PAD using a cell culture model and a mouse model of hindlimb ischemia. PVAX nanoparticles significantly enhanced the expression of angiogenic inducers such as vascular endothelial growth factor (VEGF) and platelet endothelial cell adhesion molecule (PECAM)-1 in human umbilical vein endothelial cells (HUVEC). PVAX nanoparticles promoted revascularization and restoration of blood perfusion into ischemic tissues by upregulating angiogenic VEGF and PECAM-1. This work demonstrates that H2O2-responsive PVAX nanoparticles facilitate therapeutic angiogenesis and hold tremendous translational potential as therapeutic systems for ischemic diseases such as PAD.

  11. Antioxidant airway responses following experimental exposure to wood smoke in man

    PubMed Central

    2010-01-01

    Background Biomass combustion contributes to the production of ambient particulate matter (PM) in rural environments as well as urban settings, but relatively little is known about the health effects of these emissions. The aim of this study was therefore to characterize airway responses in humans exposed to wood smoke PM under controlled conditions. Nineteen healthy volunteers were exposed to both wood smoke, at a particulate matter (PM2.5) concentration of 224 ± 22 μg/m3, and filtered air for three hours with intermittent exercise. The wood smoke was generated employing an experimental set-up with an adjustable wood pellet boiler system under incomplete combustion. Symptoms, lung function, and exhaled NO were measured over exposures, with bronchoscopy performed 24 h post-exposure for characterisation of airway inflammatory and antioxidant responses in airway lavages. Results Glutathione (GSH) concentrations were enhanced in bronchoalveolar lavage (BAL) after wood smoke exposure vs. air (p = 0.025), together with an increase in upper airway symptoms. Neither lung function, exhaled NO nor systemic nor airway inflammatory parameters in BAL and bronchial mucosal biopsies were significantly affected. Conclusions Exposure of healthy subjects to wood smoke, derived from an experimental wood pellet boiler operating under incomplete combustion conditions with PM emissions dominated by organic matter, caused an increase in mucosal symptoms and GSH in the alveolar respiratory tract lining fluids but no acute airway inflammatory responses. We contend that this response reflects a mobilisation of GSH to the air-lung interface, consistent with a protective adaptation to the investigated wood smoke exposure. PMID:20727160

  12. Anti-Oxidative Defences Are Modulated Differentially in Three Freshwater Teleosts in Response to Ammonia-Induced Oxidative Stress

    PubMed Central

    Giblen, Terri; Zinta, Gaurav; De Rop, Michelle; Asard, Han; Blust, Ronny; De Boeck, Gudrun

    2014-01-01

    Oxidative stress and the antioxidant response induced by high environmental ammonia (HEA) were investigated in the liver and gills of three freshwater teleosts differing in their sensitivities to ammonia. The highly ammonia-sensitive salmonid Oncorhynchus mykiss (rainbow trout), the less ammonia sensitive cyprinid Cyprinus carpio (common carp) and the highly ammonia-resistant cyprinid Carassius auratus (goldfish) were exposed to 1 mM ammonia (as NH4HCO3) for 0 h (control), 3 h, 12 h, 24 h, 48 h, 84 h and 180 h. Results show that HEA exposure increased ammonia accumulation significantly in the liver of all the three fish species from 24 h–48 h onwards which was associated with an increment in oxidative stress, evidenced by elevation of xanthine oxidase activity and levels of hydrogen peroxide (H2O2) and malondialdehyde (MDA). Unlike in trout, H2O2 and MDA accumulation in carp and goldfish liver was restored to control levels (84 h–180 h); which was accompanied by a concomitant increase in superoxide dismutase (SOD), catalase (CAT), ascorbate peroxidase activity and reduced ascorbate content. Many of these defence parameters remained unaffected in trout liver, while components of the glutathione redox cycle (reduced glutathione, glutathione peroxidase and glutathione reductase) enhanced to a greater extent. The present findings suggest that trout rely mainly on glutathione dependent defensive mechanism while carp utilize SOD, CAT and ascorbate as anti-oxidative sentinels. Hepatic cells of goldfish appear to utilize each of these protective systems, and showed more effective anti-oxidative compensatory responses towards HEA than carp, while trout were least effective. The present work also indicates that HEA exposure resulted in a relatively mild oxidative stress in the gills of all three species. This probably explains the almost complete lack of anti-oxidative responses in branchial tissue. This research suggests that oxidative stress, as well as the antioxidant

  13. Anti-oxidative defences are modulated differentially in three freshwater teleosts in response to ammonia-induced oxidative stress.

    PubMed

    Sinha, Amit Kumar; AbdElgawad, Hamada; Giblen, Terri; Zinta, Gaurav; De Rop, Michelle; Asard, Han; Blust, Ronny; De Boeck, Gudrun

    2014-01-01

    Oxidative stress and the antioxidant response induced by high environmental ammonia (HEA) were investigated in the liver and gills of three freshwater teleosts differing in their sensitivities to ammonia. The highly ammonia-sensitive salmonid Oncorhynchus mykiss (rainbow trout), the less ammonia sensitive cyprinid Cyprinus carpio (common carp) and the highly ammonia-resistant cyprinid Carassius auratus (goldfish) were exposed to 1 mM ammonia (as NH4HCO3) for 0 h (control), 3 h, 12 h, 24 h, 48 h, 84 h and 180 h. Results show that HEA exposure increased ammonia accumulation significantly in the liver of all the three fish species from 24 h-48 h onwards which was associated with an increment in oxidative stress, evidenced by elevation of xanthine oxidase activity and levels of hydrogen peroxide (H2O2) and malondialdehyde (MDA). Unlike in trout, H2O2 and MDA accumulation in carp and goldfish liver was restored to control levels (84 h-180 h); which was accompanied by a concomitant increase in superoxide dismutase (SOD), catalase (CAT), ascorbate peroxidase activity and reduced ascorbate content. Many of these defence parameters remained unaffected in trout liver, while components of the glutathione redox cycle (reduced glutathione, glutathione peroxidase and glutathione reductase) enhanced to a greater extent. The present findings suggest that trout rely mainly on glutathione dependent defensive mechanism while carp utilize SOD, CAT and ascorbate as anti-oxidative sentinels. Hepatic cells of goldfish appear to utilize each of these protective systems, and showed more effective anti-oxidative compensatory responses towards HEA than carp, while trout were least effective. The present work also indicates that HEA exposure resulted in a relatively mild oxidative stress in the gills of all three species. This probably explains the almost complete lack of anti-oxidative responses in branchial tissue. This research suggests that oxidative stress, as well as the antioxidant

  14. Antioxidant responses in estuarine invertebrates exposed to repeated oil spills: Effects of frequency and dosage in a field manipulative experiment.

    PubMed

    Sandrini-Neto, Leonardo; Pereira, Letícia; Martins, César C; Silva de Assis, Helena C; Camus, Lionel; Lana, Paulo C

    2016-08-01

    We have experimentally investigated the effects of repeated diesel spills on the bivalve Anomalocardia brasiliana, the gastropod Neritina virginea and the polychaete Laeonereis culveri, by monitoring the responses of oxidative stress biomarkers in a subtropical estuary. Three frequencies of exposure events were compared against two dosages of oil in a factorial experiment with asymmetrical controls. Hypotheses were tested to distinguish between (i) the overall effect of oil spills, (ii) the effect of diesel dosage via different exposure regimes, and (iii) the effect of time since last spill. Antioxidant defense responses and oxidative damage in the bivalve A. brasiliana and the polychaete L. culveri were overall significantly affected by frequent oil spills compared to undisturbed controls. The main effects of diesel spills on both species were the induction of SOD and GST activities, a significant increase in LPO levels and a decrease in GSH concentration. N. virginea was particularly tolerant to oil exposure, with the exception of a significant GSH depletion. Overall, enzymatic activities and oxidative damage in A. brasiliana and L. culveri were induced by frequent low-dosage spills compared to infrequent high-dosage spills, although the opposite pattern was observed for N. virginea antioxidant responses. Antioxidant responses in A. brasiliana and L. culveri were not affected by timing of exposure events. However, our results revealed that N. virginea might have a delayed response to acute high-dosage exposure. Experimental in situ simulations of oil exposure events with varying frequencies and intensities provide a useful tool for detecting and quantifying environmental impacts. In general, antioxidant biomarkers were induced by frequent low-dosage exposures compared to infrequent high-dosage ones. The bivalve A. brasiliana and the polychaete L. culveri are more suitable sentinels due to their greater responsiveness to oil and also to their wider geographical

  15. Antioxidant responses in estuarine invertebrates exposed to repeated oil spills: Effects of frequency and dosage in a field manipulative experiment.

    PubMed

    Sandrini-Neto, Leonardo; Pereira, Letícia; Martins, César C; Silva de Assis, Helena C; Camus, Lionel; Lana, Paulo C

    2016-08-01

    We have experimentally investigated the effects of repeated diesel spills on the bivalve Anomalocardia brasiliana, the gastropod Neritina virginea and the polychaete Laeonereis culveri, by monitoring the responses of oxidative stress biomarkers in a subtropical estuary. Three frequencies of exposure events were compared against two dosages of oil in a factorial experiment with asymmetrical controls. Hypotheses were tested to distinguish between (i) the overall effect of oil spills, (ii) the effect of diesel dosage via different exposure regimes, and (iii) the effect of time since last spill. Antioxidant defense responses and oxidative damage in the bivalve A. brasiliana and the polychaete L. culveri were overall significantly affected by frequent oil spills compared to undisturbed controls. The main effects of diesel spills on both species were the induction of SOD and GST activities, a significant increase in LPO levels and a decrease in GSH concentration. N. virginea was particularly tolerant to oil exposure, with the exception of a significant GSH depletion. Overall, enzymatic activities and oxidative damage in A. brasiliana and L. culveri were induced by frequent low-dosage spills compared to infrequent high-dosage spills, although the opposite pattern was observed for N. virginea antioxidant responses. Antioxidant responses in A. brasiliana and L. culveri were not affected by timing of exposure events. However, our results revealed that N. virginea might have a delayed response to acute high-dosage exposure. Experimental in situ simulations of oil exposure events with varying frequencies and intensities provide a useful tool for detecting and quantifying environmental impacts. In general, antioxidant biomarkers were induced by frequent low-dosage exposures compared to infrequent high-dosage ones. The bivalve A. brasiliana and the polychaete L. culveri are more suitable sentinels due to their greater responsiveness to oil and also to their wider geographical

  16. Hyperactivity of the Ero1α Oxidase Elicits Endoplasmic Reticulum Stress but No Broad Antioxidant Response

    PubMed Central

    Hansen, Henning Gram; Schmidt, Jonas Damgård; Søltoft, Cecilie Lützen; Ramming, Thomas; Geertz-Hansen, Henrik Marcus; Christensen, Brian; Sørensen, Esben Skipper; Juncker, Agnieszka Sierakowska; Appenzeller-Herzog, Christian; Ellgaard, Lars

    2012-01-01

    Oxidizing equivalents for the process of oxidative protein folding in the endoplasmic reticulum (ER) of mammalian cells are mainly provided by the Ero1α oxidase. The molecular mechanisms that regulate Ero1α activity in order to harness its oxidative power are quite well understood. However, the overall cellular response to oxidative stress generated by Ero1α in the lumen of the mammalian ER is poorly characterized. Here we investigate the effects of overexpressing a hyperactive mutant (C104A/C131A) of Ero1α. We show that Ero1α hyperactivity leads to hyperoxidation of the ER oxidoreductase ERp57 and induces expression of two established unfolded protein response (UPR) targets, BiP (immunoglobulin-binding protein) and HERP (homocysteine-induced ER protein). These effects could be reverted or aggravated by N-acetylcysteine and buthionine sulfoximine, respectively. Because both agents manipulate the cellular glutathione redox buffer, we conclude that the observed effects of Ero1α-C104A/C131A overexpression are likely caused by an oxidative perturbation of the ER glutathione redox buffer. In accordance, we show that Ero1α hyperactivity affects cell viability when cellular glutathione levels are compromised. Using microarray analysis, we demonstrate that the cell reacts to the oxidative challenge caused by Ero1α hyperactivity by turning on the UPR. Moreover, this analysis allowed the identification of two new targets of the mammalian UPR, CRELD1 and c18orf45. Interestingly, a broad antioxidant response was not induced. Our findings suggest that the hyperoxidation generated by Ero1α-C104A/C131A is addressed in the ER lumen and is unlikely to exert oxidative injury throughout the cell. PMID:23027870

  17. Optimization of Ultrasonic-Assisted Extraction of Flavonoid Compounds and Antioxidants from Alfalfa Using Response Surface Method.

    PubMed

    Jing, Chang-Liang; Dong, Xiao-Fang; Tong, Jian-Ming

    2015-08-26

    Ultrasonic-assisted extraction (UAE) was used to extract flavonoid-enriched antioxidants from alfalfa aerial part. Response surface methodology (RSM), based on a four-factor, five-level central composite design (CCD), was employed to obtain the optimal extraction parameters, in which the flavonoid content was maximum and the antioxidant activity of the extracts was strongest. Radical scavenging capacity of the extracts, which represents the amounts of antioxidants in alfalfa, was determined by using 2,2'-azino-bis (3-ethylbenzothiazoline-6-sulphonicacid) (ABTS) and 2,2'-diphenyl-1-picrylhydrazyl (DPPH) methods. The results showed good fit with the proposed models for the total flavonoid extraction (R² = 0.9849), for the antioxidant extraction assayed by ABTS method (R² = 0.9764), and by DPPH method (R² = 0.9806). Optimized extraction conditions for total flavonoids was a ratio of liquid to solid of 57.16 mL/g, 62.33 °C, 57.08 min, and 52.14% ethanol. The optimal extraction parameters of extracts for the highest antioxidant activity by DPPH method was a ratio of liquid to solid 60.3 mL/g, 54.56 °C, 45.59 min, and 46.67% ethanol, and by ABTS assay was a ratio of liquid to solid 47.29 mL/g, 63.73 °C, 51.62 min, and 60% ethanol concentration. Our work offers optimal extraction conditions for total flavonoids and antioxidants from alfalfa.

  18. Antioxidant responses of Annelids, Brassicaceae and Fabaceae to pollutants: a review.

    PubMed

    Bernard, F; Brulle, F; Dumez, S; Lemiere, S; Platel, A; Nesslany, F; Cuny, D; Deram, A; Vandenbulcke, F

    2015-04-01

    Pollutants, such as Metal Trace Elements (MTEs) and organic compounds (polycyclic aromatic hydrocarbons, pesticides), can impact DNA structure of living organisms and thus generate damage. For instance, cadmium is a well-known genotoxic and mechanisms explaining its clastogenicity are mainly indirect: inhibition of DNA repair mechanisms and/or induction of Reactive Oxygen Species (ROS). Animal or vegetal cells use antioxidant defense systems to protect themselves against ROS produced during oxidative stress. Because tolerance of organisms depends, at least partially, on their ability to cope with ROS, the mechanisms of production and management of ROS were investigated a lot in Ecotoxicology as markers of biotic and abiotic stress. This was mainly done through the measurement of enzyme activities The present Review focuses on 3 test species living in close contact with soil that are often used in soil ecotoxicology: the worm Eisenia fetida, and two plant species, Trifolium repens (white clover) and Brassica oleracea (cabbage). E. fetida is a soil-dwelling organism commonly used for biomonitoring. T. repens is a symbiotic plant species which forms root nodule with soil bacteria, while B. oleracea is a non-symbiotic plant. In literature, some oxidative stress enzyme activities have already been measured in those species but such analyses do not allow distinction between individual enzyme involvements in oxidative stress. Gene expression studies would allow this distinction at the transcriptomic level. A literature review and a data search in molecular database were carried out on the basis of keywords in Scopus, in PubMed and in Genbank™ for each species. Molecular data regarding E. fetida were already available in databases, but a lack of data regarding oxidative stress related genes was observed for T. repens and B. oleracea. By exploiting the conservation observed between species and using molecular biology techniques, we partially cloned missing candidates

  19. Antioxidant response and histopathological changes in brain tissue of pigeon exposed to avermectin.

    PubMed

    Li, Ming; You, Tian-Zi; Zhu, Wen-Jun; Qu, Jian-Ping; Liu, Ci; Zhao, Bing; Xu, Shi-Wen; Li, Shu

    2013-10-01

    Avermectins (AVMs) are the active components of some insecticidal and nematicidal products used in agriculture and veterinary medicine for the prevention of parasitic diseases. Residues of AVM drugs or their metabolites in livestock feces have toxic effects on non-target aquatic and terrestrial organisms. In this study, oxidative stress responses and pathological changes on pigeon brain tissues and serum after subchronic exposure to AVM for 30, 60 and 90 days were investigated. The decrease in antioxidant enzyme (superoxide dismutase, SOD and glutathione peroxidase, GSH-Px) activities and increase in methane dicarboxylic aldehyde content in a dose-time-dependent manner in the brain and serum of pigeon were observed. The protein carbonyl content, an indicator of protein oxidation, and DNA-protein crosslink coefficient were significantly augmented with dose-time-dependent properties. The microscopic structures of the cerebrum, cerebellum and optic lobe altered obviously, the severity of which increased with the concentration of AVM and exposure time. The results imply that AVM could induce oxidative damage to the brain tissue and serum of pigeon. The information presented in this study is helpful to understand the mechanism of AVM-induced oxidative stress in birds.

  20. Isoorientin induces Nrf2 pathway-driven antioxidant response through phosphatidylinositol 3-kinase signaling.

    PubMed

    Lim, Ju Hee; Park, Hae-Suk; Choi, Jung-Kap; Lee, Ik-Soo; Choi, Hyun Jin

    2007-12-01

    Because oxidative stress is involved in the pathogenesis of various chronic diseases and the aging process, antioxidants that can increase the intrinsic antioxidant potency are proposed as desirable therapeutic agents to counteract oxidative stress-related diseases. NF-E2-related factor-2 (Nrf2) is a transcription factor that regulates important antioxidant and phase II detoxification genes, and therefore, the molecule that regulates nuclear translocation of Nrf2 and the induction of antioxidative proteins is thought to be a promising candidate as a cytoprotective agent for oxidative stress. In the present study, we show that isoorientin (luteolin 6-C-beta-D-glucoside) obtained from the leaves of Sasa borealis upregulates and activates Nrf2, and has protective ability against oxidative damage caused by reactive oxygen intermediates in HepG2 cells. Isoorientin induces increase in the level of antioxidant enzyme proteins, especially NQO1, and the cytoprotective and antioxidative effects of isoorientin are PI3K/Akt pathway-dependent. Together with direct radical scavenging activity, the novel effect of isoorientin on the regulation of antioxidative gene expression provides attractive strategy to prevent diseases associated with oxidative stress and attenuate the progress of the diseases. PMID:18254247

  1. Arbuscular mycorrhizal symbiosis modulates antioxidant response in salt-stressed Trigonella foenum-graecum plants.

    PubMed

    Evelin, Heikham; Kapoor, Rupam

    2014-04-01

    An experiment was conducted to evaluate the influence of Glomus intraradices colonization on the activity of antioxidant enzymes [superoxide dismutase (SOD), catalase (CAT), peroxidase (PX), ascorbate peroxidase (APX), and glutathione reductase (GR)] and the accumulation of nonenzymatic antioxidants (ascorbic acid, α-tocopherol, glutathione, and carotenoids) in roots and leaves of fenugreek plants subjected to varying degrees of salinity (0, 50, 100, and 200 mM NaCl) at two time intervals (1 and 14 days after saline treatment, DAT). The antioxidative capacity was correlated with oxidative damage in the same tissue. Under salt stress, lipid peroxidation and H2O2 concentration increased with increasing severity and duration of salt stress (DoS). However, the extent of oxidative damage in mycorrhizal plants was less compared to nonmycorrhizal plants. The study reveals that mycorrhiza-mediated attenuation of oxidative stress in fenugreek plants is due to enhanced activity of antioxidant enzymes and higher concentrations of antioxidant molecules. However, the significant effect of G. intraradices colonization on individual antioxidant molecules and enzymes varied with plant tissue, salinity level, and DoS. The significant effect of G. intraradices colonization on antioxidative enzymes was more evident at 1DAT in both leaves and roots, while the concentrations of antioxidant molecules were significantly influenced at 14DAT. It is proposed that AM symbiosis can improve antioxidative defense systems of plants through higher SOD activity in M plants, facilitating rapid dismutation of O2 (-) to H2O2, and subsequent prevention of H2O2 build-up by higher activities of CAT, APX, and PX. The potential of G. intraradices to ameliorate oxidative stress generated in fenugreek plants by salinity was more evident at higher intensities of salt stress.

  2. The effect of cadmium on the growth and antioxidant response for freshwater algae Chlorella vulgaris.

    PubMed

    Cheng, Jinfeng; Qiu, Hongchen; Chang, Zhaoyang; Jiang, Zaimin; Yin, Wenke

    2016-01-01

    The objective of the present work was to evaluate the effect of exogenously applied cadmium on the physiological response of green algae Chlorella vulgaris. The study investigated the long-term effect (18 days) of cadmium on the levels of algae biomass, assimilation pigment composition, soluble protein, oxidative status (production of hydrogen peroxide and superoxide anion), antioxidant enzymes (such as superoxide dismutase, peroxidase, catalase and glutathione reductase enzyme) in C. vulgaris. The results showed that growth, the amount of chlorophyll a (Chl a), chlorophyll b (Chl b) and carotenoids gradually decreased with increasing cadmium over 18 days exposure. Cadmium at concentration of 7 mg L(-1) inhibited algal growth expressed as the number of cells. Our research found that C. vulgaris has a high tolerance to cadmium. Contents of chlorophylls (Chl a and Chl b) and carotenoids (Car) of C. vulgaris was significantly decline with rising concentration of cadmium (p < 0.05). The decrease of 54.04 and 93.37 % in Chl a, 60.65 and 74.32 % in Chl b, 50.00 and 71.88 % in total carotenoids was noticed following the treatment with 3 and 7 mg L(-1) cadmium doses compared with control treatment, respectively. Cadmium treatments caused a significant change in the physiological competence (calculated as chlorophyll a/b) which increased with increasing Cd(II) doses up to 1 mg L(-1) but decreased at 3 mg L(-1). While accumulation of soluble protein was enhanced by presence of cadmium, the treatment with cadmium at 3 and 7 mg L(-1) increased the concentration of soluble proteins by 88, 95.8 % in C. vulgaris, respectively. Moreover, low doses of cadmium stimulated enzymatic (superoxide dismutase, catalase and glutathione reductase) in C. vulgaris, The content of peroxidase increased with the increasing cadmium concentration, and had slightly decreased at the concentration of 7 mg L(-1), but was still higher than control group, which showed that cadmium

  3. The effect of cadmium on the growth and antioxidant response for freshwater algae Chlorella vulgaris.

    PubMed

    Cheng, Jinfeng; Qiu, Hongchen; Chang, Zhaoyang; Jiang, Zaimin; Yin, Wenke

    2016-01-01

    The objective of the present work was to evaluate the effect of exogenously applied cadmium on the physiological response of green algae Chlorella vulgaris. The study investigated the long-term effect (18 days) of cadmium on the levels of algae biomass, assimilation pigment composition, soluble protein, oxidative status (production of hydrogen peroxide and superoxide anion), antioxidant enzymes (such as superoxide dismutase, peroxidase, catalase and glutathione reductase enzyme) in C. vulgaris. The results showed that growth, the amount of chlorophyll a (Chl a), chlorophyll b (Chl b) and carotenoids gradually decreased with increasing cadmium over 18 days exposure. Cadmium at concentration of 7 mg L(-1) inhibited algal growth expressed as the number of cells. Our research found that C. vulgaris has a high tolerance to cadmium. Contents of chlorophylls (Chl a and Chl b) and carotenoids (Car) of C. vulgaris was significantly decline with rising concentration of cadmium (p < 0.05). The decrease of 54.04 and 93.37 % in Chl a, 60.65 and 74.32 % in Chl b, 50.00 and 71.88 % in total carotenoids was noticed following the treatment with 3 and 7 mg L(-1) cadmium doses compared with control treatment, respectively. Cadmium treatments caused a significant change in the physiological competence (calculated as chlorophyll a/b) which increased with increasing Cd(II) doses up to 1 mg L(-1) but decreased at 3 mg L(-1). While accumulation of soluble protein was enhanced by presence of cadmium, the treatment with cadmium at 3 and 7 mg L(-1) increased the concentration of soluble proteins by 88, 95.8 % in C. vulgaris, respectively. Moreover, low doses of cadmium stimulated enzymatic (superoxide dismutase, catalase and glutathione reductase) in C. vulgaris, The content of peroxidase increased with the increasing cadmium concentration, and had slightly decreased at the concentration of 7 mg L(-1), but was still higher than control group, which showed that cadmium

  4. Induction of Antioxidant and Heat Shock Protein Responses During Torpor in the Gray Mouse Lemur, Microcebus murinus.

    PubMed

    Wu, Cheng-Wei; Biggar, Kyle K; Zhang, Jing; Tessier, Shannon N; Pifferi, Fabien; Perret, Martine; Storey, Kenneth B

    2015-04-01

    A natural tolerance of various environmental stresses is typically supported by various cytoprotective mechanisms that protect macromolecules and promote extended viability. Among these are antioxidant defenses that help to limit damage from reactive oxygen species and chaperones that help to minimize protein misfolding or unfolding under stress conditions. To understand the molecular mechanisms that act to protect cells during primate torpor, the present study characterizes antioxidant and heat shock protein (HSP) responses in various organs of control (aroused) and torpid gray mouse lemurs, Microcebus murinus. Protein expression of HSP70 and HSP90α was elevated to 1.26 and 1.49 fold, respectively, in brown adipose tissue during torpor as compared with control animals, whereas HSP60 in liver of torpid animals was 1.15 fold of that in control (P<0.05). Among antioxidant enzymes, protein levels of thioredoxin 1 were elevated to 2.19 fold in white adipose tissue during torpor, whereas Cu-Zn superoxide dismutase 1 levels rose to 1.1 fold in skeletal muscle (P<0.05). Additionally, total antioxidant capacity was increased to 1.6 fold in liver during torpor (P<0.05), while remaining unchanged in the five other tissues. Overall, our data suggest that antioxidant and HSP responses are modified in a tissue-specific manner during daily torpor in gray mouse lemurs. Furthermore, our data also show that cytoprotective strategies employed during primate torpor are distinct from the strategies in rodent hibernation as reported in previous studies. PMID:26092183

  5. Adipose triglyceride lipase decrement affects skeletal muscle homeostasis during aging through FAs-PPARα-PGC-1α antioxidant response

    PubMed Central

    Aquilano, Katia; Baldelli, Sara; Barbera, Livia La; Barbato, Daniele Lettieri; Tatulli, Giuseppe; Ciriolo, Maria Rosa

    2016-01-01

    During aging skeletal muscle shows an accumulation of oxidative damage as well as intramyocellular lipid droplets (IMLDs). However, although the impact of these modifications on muscle tissue physiology is well established, the direct effectors critical for their occurrence are poorly understood. Here we show that during aging the main lipase of triacylglycerols, ATGL, significantly declines in gastrocnemius and its downregulation in C2C12 myoblast leads to the accumulation of lipid droplets. Indeed, we observed an increase of oxidative damage to proteins in terms of carbonylation, S-nitrosylation and ubiquitination that is dependent on a defective antioxidant cell response mediated by ATGL-PPARα-PGC-1α. Overall our findings describe a pivotal role for ATGL in the antioxidant/anti-inflammatory response of muscle cells highlighting this lipase as a therapeutic target for fighting the progressive decline in skeletal muscle mass and strength. PMID:27056902

  6. Activation of the Nrf2-regulated antioxidant cell response inhibits HEMA-induced oxidative stress and supports cell viability.

    PubMed

    Gallorini, Marialucia; Petzel, Christine; Bolay, Carola; Hiller, Karl-Anton; Cataldi, Amelia; Buchalla, Wolfgang; Krifka, Stephanie; Schweikl, Helmut

    2015-07-01

    Oxidative stress due to increased formation of reactive oxygen species (ROS) in target cells of dental resin monomers like 2-hydroxyethyl methacrylate (HEMA) is a major mechanism underlying the disturbance of vital cell functions including mineralization and differentiation, responses of the innate immune system, and the induction of cell death via apoptosis. Although a shift in the equilibrium between cell viability and apoptosis is related to the non-enzymatic antioxidant glutathione (GSH) in HEMA-exposed cells, the major mechanisms of adaptive antioxidant cell responses to maintain cellular redox homeostasis are still unknown. The present study provides insight into the induction of a communicating network of pathways under the control of the redox-sensitive transcription factor Nrf2, a major transcriptional activator of genes coding for enzymatic antioxidants. Here, oxidative stress was indicated by DCF fluorescence in cells after a short exposure (1 h) to HEMA, while DHR123 fluorescence significantly increased about 1.8-fold after a long exposure period (24 h) showing the formation of hydrogen peroxide (H2O2). The corresponding expression of Nrf2 was activated immediately after HEMA exposure (1 h) and remained constant up to 24 h. Nrf2-regulated expression of enzymes of the glutathione metabolism (glutathione peroxidase 1/2, glutathione reductase) decreased in HEMA-exposed cells as a result of GSH depletion, and superoxide dismutase expression was downregulated after H2O2 overproduction. However, the expression of Nrf2-controlled enzymatic antioxidants (catalase, peroxiredoxin, thioredoxin 1, thioredoxin reductase, heme oxygenase-1) and the NADPH-regenerating system (glucose 6-phosphate dehydrogenase, transaldolase) was increased. Phenolic tert-butylhydroquinone (tBHQ), a classic inducer of the Nrf2 pathway, reduced oxidative stress and protected cells from HEMA-induced cell death through a shift in the number of cells in necrosis to apoptosis. The

  7. Optimization of microwave-assisted extraction for anthocyanins, polyphenols, and antioxidants from raspberry (Rubus Coreanus Miq.) using response surface methodology.

    PubMed

    Teng, Hui; Lee, Won Young; Choi, Yong Hee

    2013-09-01

    Anthocyanins (Acys), polyphenols, and antioxidants were extracted from raspberry (Rubus Coreanus Miq.) using a highly efficient microwave-assisted extraction technique. Different solvents, including methanol, ethanol, and acetone, were tested. The colors of the extracts varied from light yellow to purple red or dark red. SEM and other nutrient analyses verified that ethanol was the most favorable medium for the microwave-assisted extraction of raspberry due to its high output and low toxicity. Effects of process parameters, including microwave power, irradiation time, and solvent concentration, were investigated through response surface methodology. Canonical analysis estimated that the highest total Acys content, total polyphenols content, and antioxidant activity of raspberry were 17.93 mg cyanidin-3-O-glucoside equivalents per gram dry weight, 38.57 mg gallic acid equivalents per gram dry weight, and 81.24%, respectively. The polyphenol compositions of raspberry extract were identified by HPLC with diode array detection, and nine kinds of polyphenols were identified and quantified, revealing that chlorogenic acid, syringic acid, and rutin are the major polyphenols contained in raspberry fruits. Compared with other fruits and vegetables, raspberry contains higher Acy and polyphenol contents with stronger antioxidant activity, suggesting that raspberry fruits are a good source of natural food colorants and antioxidants.

  8. Extraction optimization for antioxidant phenolic compounds in red grape jam using ultrasound with a response surface methodology.

    PubMed

    Morelli, Lucíula Lemos Lima; Prado, Marcelo Alexandre

    2012-11-01

    Optimization of the extraction methodology for antioxidant phenolic compounds in red grape jam was performed with an ultrasound-assisted system. The antioxidant phenolic compounds were extracted and analyzed by determining the total phenolic content (Folin Ciocalteu), as well as by employing free radical DPPH() and the beta-carotene/linoleic acid system. To optimize the parameters of solvent concentration, time and extraction temperature, the experiments were carried out using the central composite rotatable design (CCRD) method. Using response surface methodology (RSM), the best combinations achieved were with 60% ethanol and water for 20min at 50°C. The optimized parameters for this method were compared to an extraction method that has been commonly noted in the literature, which used to be the standard method, and the results were expressed in the milligram equivalent of quercetin per gram of jam (mg E.Q/g Jam). With the new method, the antioxidant potential measured by DPPH(ⁱ) was 70% higher than that obtained with the standard extraction method, and the antioxidant potential measured using the beta-carotene/linoleic acid system was 65% higher. In addition, a significant decrease in the total analysis time was achieved (from 10h to 30min), when compared to the standard method. PMID:22512996

  9. Finite-element impact response of debonded composite turbine blades

    NASA Astrophysics Data System (ADS)

    Dey, Sudip; Karmakar, Amit

    2014-02-01

    This paper investigates on the transient behavior of debonded composite pretwisted rotating shallow conical shells which could be idealized as turbine blades subjected to low velocity normal impact using finite-element method. Lagrange's equation of motion is used to derive the dynamic equilibrium equation and the moderate rotational speeds are considered neglecting the Coriolis effect. An eight-noded isoparametric plate bending element is employed in the finite element formulation incorporating rotary inertia and effects of transverse shear deformation based on Mindlin's theory. The modified Hertzian contact law which accounts for permanent indentation is utilized to compute the impact parameters. The time-dependent equations are solved by using Newmark's time integration scheme. Parametric studies are performed to investigate the effects of triggering parameters like angle of twist, rotational speed, laminate configuration and location of debonding considering low velocity normal impact at the center of eight-layered graphite-epoxy composite cantilevered conical shells with bending stiff ([0o2/{±} 30o]s), torsion stiff ([45°/-45°/-45°/45°]s) and cross-ply ([0°/90°/0°/90°]s) laminate configurations.

  10. Population responses to contour integration: early encoding of discrete elements and late perceptual grouping.

    PubMed

    Gilad, Ariel; Meirovithz, Elhanan; Slovin, Hamutal

    2013-04-24

    The neuronal mechanisms underlying perceptual grouping of discrete, similarly oriented elements are not well understood. To investigate this, we measured neural population responses using voltage-sensitive dye imaging in V1 of monkeys trained on a contour-detection task. By mapping the contour and background elements onto V1, we could study their neural processing. Population response early in time showed activation patches corresponding to the contour/background individual elements. However, late increased activity in the contour elements, along with suppressed activity in the background elements, enabled us to visualize in single trials a salient continuous contour "popping out" from a suppressed background. This modulated activity in the contour and in background extended beyond the cortical representation of individual contour or background elements. Finally, the late modulation was correlated with behavioral performance of contour saliency and the monkeys' perceptual report. Thus, opposing responses in the contour and background may underlie perceptual grouping in V1.

  11. Comparison of physiological and antioxidant responses of Anoda cristata and cotton to progressive drought

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Simultaneous investigation of variables related to gas exchange, photochemistry and antioxidant defenses during water stress is crucial for understanding stress tolerance mechanisms and consequent success of both economically important plant species and their interfering counterparts. This study ev...

  12. Antioxidative responses of Pseudomonas fluorescens YZ2 to simultaneous exposure of Zn and Cefradine.

    PubMed

    Xu, Yan-Bin; Xu, Jia-Xin; Chen, Jin-Liang; Huang, Lu; Zhou, Shao-Qi; Zhou, Yan; Wen, Li-Hua

    2015-10-01

    Binary pollution of both heavy metals and antibiotics has received increasing attentions for their joint effects of eco-toxicity and health hazards. To reveal the effects of mixtures of different pollutants on bacterial antioxidant response system, Pseudomonas fluorescens ZY2, a new strain isolated from swine wastewater, was chosen to determinate growth (bacterial density OD600), reactive oxygen species (ROS) concentration, protein concentration and superoxide dismutase (SOD) activity under exposure treatments of Zn, Cefradine or Zn + Cefradine. Bacterial densities of all the treatment groups increased significantly over the incubation time, but those containing pollutant addition were slightly lower than the control at different times of incubation. Both ROS concentration and SOD activity increased first and then decreased (p < 0.01) over time, which was opposite to the protein concentrations (p < 0.01), showing a much significant increase by Cefradine alone. With Zn concentration increasing from 40 to 160 mg/L, the intracellular SOD activity increased as a response to the improvement of ROS (p < 0.05), while the balance between ROS and SOD was broken down due to the disproportionate change of total SOD activity and ROS concentration, the bacterial densities therefore decreased for the weak resistance. With the combined treatment of Zn (200 mg/L) and Cefradine (1 mg/L), though the toxicity of Zn caused a much significant increase of ROS, the bacterial resistance was further improved showing a more significant increase of total SOD activity and the bacterial densities therefore increased bacterial growth. Zn concentration also affected the protein synthesis. Either single or binary stress induced the bacterial resistance by regulating SOD activity to eliminate ROS. All results of the bacterial oxidant stress, SOD response and protein synthesis in the combined treatment groups were more complicated than those in single treatment groups, which depended on the

  13. Differential coral bleaching-Contrasting the activity and response of enzymatic antioxidants in symbiotic partners under thermal stress.

    PubMed

    Krueger, Thomas; Hawkins, Thomas D; Becker, Susanne; Pontasch, Stefanie; Dove, Sophie; Hoegh-Guldberg, Ove; Leggat, William; Fisher, Paul L; Davy, Simon K

    2015-12-01

    Mass coral bleaching due to thermal stress represents a major threat to the integrity and functioning of coral reefs. Thermal thresholds vary, however, between corals, partly as a result of the specific type of endosymbiotic dinoflagellate (Symbiodinium sp.) they harbour. The production of reactive oxygen species (ROS) in corals under thermal and light stress has been recognised as one mechanism that can lead to cellular damage and the loss of their symbiont population (Oxidative Theory of Coral Bleaching). Here, we compared the response of symbiont and host enzymatic antioxidants in the coral species Acropora millepora and Montipora digitata at 28°C and 33°C. A. millepora at 33°C showed a decrease in photochemical efficiency of photosystem II (PSII) and increase in maximum midday excitation pressure on PSII, with subsequent bleaching (declining photosynthetic pigment and symbiont density). M. digitata exhibited no bleaching response and photochemical changes in its symbionts were minor. The symbiont antioxidant enzymes superoxide dismutase, ascorbate peroxidase, and catalase peroxidase showed no significant upregulation to elevated temperatures in either coral, while only catalase was significantly elevated in both coral hosts at 33°C. Increased host catalase activity in the susceptible coral after 5days at 33°C was independent of antioxidant responses in the symbiont and preceded significant declines in PSII photochemical efficiencies. This finding suggests a potential decoupling of host redox mechanisms from symbiont photophysiology and raises questions about the importance of symbiont-derived ROS in initiating coral bleaching.

  14. Differential response of Arabidopsis leaves and roots to cadmium: glutathione-related chelating capacity vs antioxidant capacity.

    PubMed

    Jozefczak, Marijke; Keunen, Els; Schat, Henk; Bliek, Mattijs; Hernández, Luis E; Carleer, Robert; Remans, Tony; Bohler, Sacha; Vangronsveld, Jaco; Cuypers, Ann

    2014-10-01

    This study aims to uncover the spatiotemporal involvement of glutathione (GSH) in two major mechanisms of cadmium (Cd)-induced detoxification (i.e. chelation and antioxidative defence). A kinetic study was conducted on hydroponically grown Arabidopsis thaliana (L. Heyhn) to gain insight into the early events after exposure to Cd. Cadmium detoxification was investigated at different levels, including gene transcripts, enzyme activities and metabolite content. Data indicate a time-dependent response both within roots and between plant organs. Early on in roots, GSH was preferentially allocated to phytochelatin (PC) synthesis destined for Cd chelation. This led to decreased GSH levels, without alternative pathways activated to complement GSH's antioxidative functions. After one day however, multiple antioxidative pathways increased including superoxide dismutase (SOD), ascorbate (AsA) and catalase (CAT) to ensure efficient neutralization of Cd-induced reactive oxygen species (ROS). As a consequence of Cd retention and detoxification in roots, a delayed response occurred in leaves. Together with high leaf thiol contents and possibly signalling responses from the roots, the leaves were protected, allowing them sufficient time to activate their defence mechanisms. PMID:25049163

  15. Antioxidant defense response induced by Trichoderma viride against Aspergillus niger Van Tieghem causing collar rot in groundnut (Arachis hypogaea L.).

    PubMed

    Gajera, H P; Katakpara, Zinkal A; Patel, S V; Golakiya, B A

    2016-02-01

    The study was conducted to examine the antioxidant enzymes induced by Trichoderma viride JAU60 as initial defense response during invasion of rot pathogen Aspergillus niger Van Tieghem in five groundnut varieties under pot culture. Seed treatment of T. viride JAU60 reduced 51-58% collar rot disease incidence in different groundnut varieties under pathogen infected soil culture. The activities of the antioxidant enzymes, viz., superoxide dismutase (SOD, EC 1.15.1.1), guaiacol peroxidase (GPX, EC 1.11.1.7) and ascorbate peroxidase (APX, EC 1.11.1.11), elevated in response to pathogen infection, in higher rate by tolerant varieties (J-11 and GG-2) compared with susceptible (GAUG-10, GG-13, GG-20) and further induced by T. viride treatment. Trichoderma treatment remarkably increased the 2.3 fold SOD, 5 fold GPX and 2.5 fold APX activities during disease development in tolerant varieties and the same was found about 1.2, 1.5 and 2.0 folds, respectively, in susceptible varieties. Overall, T. viride JAU60 treated seedlings (T3) witnessed higher activities of SOD (1.5 fold), GPX (3.25 fold) and APX (1.25 fold) than pathogen treatment (T2) possibly suggest the induction of antioxidant defense response by Trichoderma bio-controller to combat oxidative burst produced by invading pathogen.

  16. Differential coral bleaching-Contrasting the activity and response of enzymatic antioxidants in symbiotic partners under thermal stress.

    PubMed

    Krueger, Thomas; Hawkins, Thomas D; Becker, Susanne; Pontasch, Stefanie; Dove, Sophie; Hoegh-Guldberg, Ove; Leggat, William; Fisher, Paul L; Davy, Simon K

    2015-12-01

    Mass coral bleaching due to thermal stress represents a major threat to the integrity and functioning of coral reefs. Thermal thresholds vary, however, between corals, partly as a result of the specific type of endosymbiotic dinoflagellate (Symbiodinium sp.) they harbour. The production of reactive oxygen species (ROS) in corals under thermal and light stress has been recognised as one mechanism that can lead to cellular damage and the loss of their symbiont population (Oxidative Theory of Coral Bleaching). Here, we compared the response of symbiont and host enzymatic antioxidants in the coral species Acropora millepora and Montipora digitata at 28°C and 33°C. A. millepora at 33°C showed a decrease in photochemical efficiency of photosystem II (PSII) and increase in maximum midday excitation pressure on PSII, with subsequent bleaching (declining photosynthetic pigment and symbiont density). M. digitata exhibited no bleaching response and photochemical changes in its symbionts were minor. The symbiont antioxidant enzymes superoxide dismutase, ascorbate peroxidase, and catalase peroxidase showed no significant upregulation to elevated temperatures in either coral, while only catalase was significantly elevated in both coral hosts at 33°C. Increased host catalase activity in the susceptible coral after 5days at 33°C was independent of antioxidant responses in the symbiont and preceded significant declines in PSII photochemical efficiencies. This finding suggests a potential decoupling of host redox mechanisms from symbiont photophysiology and raises questions about the importance of symbiont-derived ROS in initiating coral bleaching. PMID:26310104

  17. Antioxidant defense response induced by Trichoderma viride against Aspergillus niger Van Tieghem causing collar rot in groundnut (Arachis hypogaea L.).

    PubMed

    Gajera, H P; Katakpara, Zinkal A; Patel, S V; Golakiya, B A

    2016-02-01

    The study was conducted to examine the antioxidant enzymes induced by Trichoderma viride JAU60 as initial defense response during invasion of rot pathogen Aspergillus niger Van Tieghem in five groundnut varieties under pot culture. Seed treatment of T. viride JAU60 reduced 51-58% collar rot disease incidence in different groundnut varieties under pathogen infected soil culture. The activities of the antioxidant enzymes, viz., superoxide dismutase (SOD, EC 1.15.1.1), guaiacol peroxidase (GPX, EC 1.11.1.7) and ascorbate peroxidase (APX, EC 1.11.1.11), elevated in response to pathogen infection, in higher rate by tolerant varieties (J-11 and GG-2) compared with susceptible (GAUG-10, GG-13, GG-20) and further induced by T. viride treatment. Trichoderma treatment remarkably increased the 2.3 fold SOD, 5 fold GPX and 2.5 fold APX activities during disease development in tolerant varieties and the same was found about 1.2, 1.5 and 2.0 folds, respectively, in susceptible varieties. Overall, T. viride JAU60 treated seedlings (T3) witnessed higher activities of SOD (1.5 fold), GPX (3.25 fold) and APX (1.25 fold) than pathogen treatment (T2) possibly suggest the induction of antioxidant defense response by Trichoderma bio-controller to combat oxidative burst produced by invading pathogen. PMID:26620080

  18. Rhizobial symbiosis effect on the growth, metal uptake, and antioxidant responses of Medicago lupulina under copper stress.

    PubMed

    Kong, Zhaoyu; Mohamad, Osama Abdalla; Deng, Zhenshan; Liu, Xiaodong; Glick, Bernard R; Wei, Gehong

    2015-08-01

    The effects of rhizobial symbiosis on the growth, metal uptake, and antioxidant responses of Medicago lupulina in the presence of 200 mg kg(-1) Cu(2+) throughout different stages of symbiosis development were studied. The symbiosis with Sinorhizobium meliloti CCNWSX0020 induced an increase in plant growth and nitrogen content irrespective of the presence of Cu(2+). The total amount of Cu uptake of inoculated plants significantly increased by 34.0 and 120.4% in shoots and roots, respectively, compared with non-inoculated plants. However, although the rhizobial symbiosis promoted Cu accumulation both in shoots and roots, the increase in roots was much higher than in shoots, thus decreasing the translocation factor and helping Cu phytostabilization. The rate of lipid peroxidation was significantly decreased in both shoots and roots of inoculated vs. non-inoculated plants when measured either 8, 13, or 18 days post-inoculation. In comparison with non-inoculated plants, the activities of superoxide dismutase and ascorbate peroxidase of shoots of inoculated plants exposed to excess Cu were significantly elevated at different stages of symbiosis development; similar increases occurred in the activities of superoxide dismutase, catalase, and glutathione reductase of inoculated roots. The symbiosis with S. meliloti CCNWSX0020 also upregulated the corresponding genes involved in antioxidant responses in the plants treated with excess Cu. The results indicated that the rhizobial symbiosis with S. meliloti CCNWSX0020 not only enhanced plant growth and metal uptake but also improved the responses of plant antioxidant defense to excess Cu stress.

  19. Heterogeneous Porphyromonas gingivalis LPS modulates immuno-inflammatory response, antioxidant defense and cytoskeletal dynamics in human gingival fibroblasts

    PubMed Central

    Herath, Thanuja D. K.; Darveau, Richard P.; Seneviratne, Chaminda J.; Wang, Cun-Yu; Wang, Yu; Jin, Lijian

    2016-01-01

    Periodontal (gum) disease is a highly prevalent infection and inflammation accounting for the majority of tooth loss in adult population worldwide. Porphyromonas gingivalis is a keystone periodontal pathogen and its lipopolysaccharide (PgLPS) acts as a major virulence attribute to the disease. Herein, we deciphered the overall host response of human gingival fibroblasts (HGFs) to two featured isoforms of tetra-acylated PgLPS1435/1449 and penta-acylated PgLPS1690 with reference to E. coli LPS through quantitative proteomics. This study unraveled differentially expressed novel biomarkers of immuno-inflammatory response, antioxidant defense and cytoskeletal dynamics in HGFs. PgLPS1690 greatly upregulated inflammatory proteins (e.g. cyclophilin, inducible nitric oxide synthase, annexins, galectin, cathepsins and heat shock proteins), whereas the anti-inflammatory proteins (e.g. Annexin A2 and Annexin A6) were significantly upregulated by PgLPS1435/1449. Interestingly, the antioxidants proteins such as mitochondrial manganese-containing superoxide dismutase and peroxiredoxin 5 were only upregulated by PgLPS1690. The cytoskeletal rearrangement-related proteins like myosin were differentially regulated by these PgLPS isoforms. The present study gives new insight into the biological properties of P. gingivalis LPS lipid A moiety that could critically modulate immuno-inflammatory response, antioxidant defense and cytoskeletal dynamics in HGFs, and thereby enhances our understanding of periodontal pathogenesis. PMID:27538450

  20. Mitochondria-targeted antioxidants.

    PubMed

    Oyewole, Anne O; Birch-Machin, Mark A

    2015-12-01

    Redox homeostasis is maintained by the antioxidant defense system, which is responsible for eliminating a wide range of oxidants, including reactive oxygen species (ROS), lipid peroxides, and metals. Mitochondria-localized antioxidants are widely studied because the mitochondria, the major producers of intracellular ROS, have been linked to the cause of aging and other chronic diseases. Mitochondria-targeted antioxidants have shown great potential because they cross the mitochondrial phospholipid bilayer and eliminate ROS at the heart of the source. Growing evidence has identified mitochondria-targeted antioxidants, such as MitoQ and tiron, as potentially effective antioxidant therapies against the damage caused by enhanced ROS generation. This literature review summarizes the current knowledge on mitochondria-targeted antioxidants and their contribution to the body's antioxidant defense system. In addition to addressing the concerns surrounding current antioxidant strategies, including difficulties in targeting antioxidant treatment to sites of pathologic oxidative damage, we discuss promising therapeutic agents and new strategic approaches.

  1. Effects of fertilizing with N, p, se, and zn on regulating the element and functional component contents and antioxidant activity of tea leaves planted in red soil.

    PubMed

    Yang, Tingting; Li, Hongyan; Hu, Xiaofei; Li, Jing; Hu, Jiangning; Liu, Rong; Deng, Ze-Yuan

    2014-04-30

    New fertilizing strategies (with exogenetic N, P, Se, and Zn) were explored to regulate the element (Se, Zn, Mn, and Al) and functional component (polyphenol, catechins, free amino acid, polysaccharide, and caffeine) contents of new (a bud and two leaves, grown for about 10 days) and old tea leaves (grown for >3 months) cultivated in a hilly red soil region. Using four different fertilizing strategies (A, Se + Zn; B, Se + Zn + N; C, Se + Zn + P; D, Se + Zn + N + P), the Al and Mn contents of tea leaves in both new and old leaves were significantly decreased. Meanwhile, the contents of Se and Zn were increased, and the contents of some functional components as well as the antioxidant activities in tea leaves were improved. In particular, fertilizing strategy C showed the highest Se (0.444 μg/kg), total polyphenol (28.294%), and catechins (131.852 mg/g) contents and antioxidant activities (DPPH, 95.06%; FRAP, 3.81 mmol FeSO4/g; reducing power, 1.26) as well as the lowest Al (222.005 mg/kg) content among these four strategies, whereas fertilizing strategy B showed the highest Zn (34.235 mg/kg), total free amino acid (5.60%), tea polysaccharide (5.79%), and caffeine (56.684 mg/g) contents as well as the lowest Mn content (747.658 mg/kg). It has been proven that exogenetic elements (N, P, Se, and Zn) as fertilizers could be an effective way to produce tea leaves with higher Se, Zn, and functional component contents and antioxidant activity as well as lower Al and Mn contents in a red soil region.

  2. Early osmotic, antioxidant, ionic, and redox responses to salinity in leaves and roots of Indian mustard (Brassica juncea L.).

    PubMed

    Ranjit, Singh Laxmi; Manish, Pandey; Penna, Suprasanna

    2016-01-01

    Salt-stress-induced alterations in osmotic, ionic, and redox responses were studied in the early period of treatment (30 min to 5 days) in seedlings of Brassica juncea L. Roots and shoots under mild (50 mM) and severe (250 mM) NaCl stress were analyzed for growth, oxidative stress, osmolyte accumulation, antioxidant defense, and redox state. Growth reduction was less pronounced in the early time period of salt stress while oxidative damage increased linearly and in a sustained manner under severe stress up to 6 h. An early and transient reactive oxygen species (ROS) burst, as evidenced by superoxide and hydrogen peroxide level was observed, followed by activation of enzymatic antioxidant system (GPX, SOD, CAT, and GR) in both root and shoot. The enzymatic activity was not affected much under mild stress particularly at early phase; however, severe stress induced a significant increase in the activity of antioxidant enzymes. Root ascorbate was progressively accumulated, and its redox state maintained in the early time phase of treatment under mild stress while increase in root and shoot glutathione content was recorded under mild stress at 5 days when the active ascorbate pool decreased. While early period of salt stress showed significant Na(+) accumulation over control, plants subjected to mild stress measured less Na(+) accumulation up to 5 days compared to severely stressed plants. The results showed an early induction of differential responses to salt stress in roots and shoots of Brassica which include growth limitations, reduced relative water content, increased osmolytes, redox state, and antioxidant system, and a significant Na(+) increase. The results also indicate that roots and shoots may have distinct mechanisms of responses to salt stress.

  3. Responses of Antioxidant Enzymes in Catfish Exposed to Liquid Crystals from E-Waste

    PubMed Central

    An, Ran; Li, Yadong; Niu, Xiaojun; Yu, Hongtao

    2008-01-01

    Liquid crystals (LCs) are typically elongated organic molecules with a non-uniform distribution of electrical charges leading to a dipole. LCs are widely used in displays of computers and other electronic devices. The rapid obsolescence rate of electronics results in large amounts of liquid crystal displays (LCDs) entering the environment. Data on health effects of LCs on living creatures are currently limited to some acute toxicity tests by a few major LC manufacturers. These tests concluded that the vast majority of LCs are not acutely toxic. Since the amount of LCs in electronic devices is very small, the health effects of LCs at low concentrations or doses become important. Catfish were used as the test animals in this study. Four major enzymes of the fish’s antioxidant defense system catalase (CAT), superoxide dismutase (SOD), selenium-dependent glutathione peroxidase (Se-GPx), and glutathione-S-transferase (GST) were chosen as biomarkers to examine effects of LCs, which were taken from obsolete laptop personal computers made in the early 1990s. The catfish were fed with food containing different contents of LCs for 40 days. Activities of the four chosen enzymes in fish livers were assayed. The results showed that there were significant inductions of CAT, SOD, and Se-GPx activities in response to the LC doses. The plots of the enzyme activities versus LC doses suggested an occurrence of oxidative stress when the dose reached about 20 μg LC/g fish·d. It was concluded that LCs can cause pollutant-induced stress to catfish at low doses. CAT, SOD and Se-GPx are effective biomarkers to give early warning on potential health effects of LCs on some aquatic lives including catfish. PMID:18678923

  4. Moral Responsibility: The Missing Element in Educational Leadership

    ERIC Educational Resources Information Center

    Vasillopulos, Christopher; Denney, Morgan

    2013-01-01

    We intend to deepen the understanding of leadership in general and educational leadership in particular by an analysis of Chester Barnard's (1938) concept of executive responsibility. By so doing we believe that we will reveal how an educational leader can foster the environment in which competent teachers can optimize their students' learning…

  5. Differential Antioxidant Responses and Perturbed Porphyrin Biosynthesis after Exposure to Oxyfluorfen and Methyl Viologen in Oryza sativa.

    PubMed

    Pham, Nhi-Thi; Kim, Jin-Gil; Jung, Sunyo

    2015-07-21

    We compared antioxidant responses and regulation of porphyrin metabolism in rice plants treated with oxyfluorfen (OF) or methyl viologen (MV). Plants treated with MV exhibited not only greater increases in conductivity and malondialdehyde but also a greater decline in Fv/Fm, compared to plants treated with OF. MV-treated plants had greater increases in activities of superoxide dismutase (SOD) and catalase (CAT) as well as transcript levels of SODA and CATA than OF-treated plants after 28 h of the treatments, whereas increases in ascorbate peroxidase (APX) activity and transcript levels of APXA and APXB were greater in OF-treated plants. Both OF- and MV-treated plants resulted in not only down-regulation of most genes involved in porphyrin biosynthesis but also disappearance of Mg-porphyrins during the late stage of photooxidative stress. By contrast, up-regulation of heme oxygenase 2 (HO2) is possibly part of an efficient antioxidant response to compensate photooxidative damage in both treatments. Our data show that down-regulated biosynthesis and degradation dynamics of porphyrin intermediates have important roles in photoprotection of plants from perturbed porphyrin biosynthesis and photosynthetic electron transport. This study suggests that porphyrin scavenging as well as strong antioxidative activities are required for mitigating reactive oxygen species (ROS) production under photooxidative stress caused by OF and MV.

  6. Differential Antioxidant Responses and Perturbed Porphyrin Biosynthesis after Exposure to Oxyfluorfen and Methyl Viologen in Oryza sativa

    PubMed Central

    Pham, Nhi-Thi; Kim, Jin-Gil; Jung, Sunyo

    2015-01-01

    We compared antioxidant responses and regulation of porphyrin metabolism in rice plants treated with oxyfluorfen (OF) or methyl viologen (MV). Plants treated with MV exhibited not only greater increases in conductivity and malondialdehyde but also a greater decline in Fv/Fm, compared to plants treated with OF. MV-treated plants had greater increases in activities of superoxide dismutase (SOD) and catalase (CAT) as well as transcript levels of SODA and CATA than OF-treated plants after 28 h of the treatments, whereas increases in ascorbate peroxidase (APX) activity and transcript levels of APXA and APXB were greater in OF-treated plants. Both OF- and MV-treated plants resulted in not only down-regulation of most genes involved in porphyrin biosynthesis but also disappearance of Mg-porphyrins during the late stage of photooxidative stress. By contrast, up-regulation of heme oxygenase 2 (HO2) is possibly part of an efficient antioxidant response to compensate photooxidative damage in both treatments. Our data show that down-regulated biosynthesis and degradation dynamics of porphyrin intermediates have important roles in photoprotection of plants from perturbed porphyrin biosynthesis and photosynthetic electron transport. This study suggests that porphyrin scavenging as well as strong antioxidative activities are required for mitigating reactive oxygen species (ROS) production under photooxidative stress caused by OF and MV. PMID:26197316

  7. Tissue-specific antioxidant responses in pale chub (Zacco platypus) exposed to copper and benzo[a]pyrene.

    PubMed

    Kim, Woo-Keun; Park, June-Woo; Lim, Eun-Suk; Lee, Sung-Kyu; Kim, Jungkon; Kim, Sunmi; Lee, Sang-Woo; Choi, Kyungho; Jung, Jinho

    2014-05-01

    In this study, antioxidant responses including lipid peroxidation (LPO), superoxide dismutase (SOD), catalase (CAT) and glutathione S-transferase (GST), were evaluated in the liver, gill and muscle tissues of pale chub (Zacco platypus) exposed to copper (Cu) and benzo[a]pyrene (BaP). Cu exposure induced significant antioxidant responses in Z. platypus, particularly in the liver, whereas BaP exposure had a negligible effect. Following Cu exposure, both SOD and CAT activity increased in a concentration-dependent manner, showing significant correlations with malondialdehyde (MDA) levels as a measure of LPO (r = 0.646 and 0.663, respectively). SOD, CAT and GST mRNA levels were also enhanced following Cu exposure, except at 20 μg L(-1), although significant correlations with antioxidant enzyme activities were not found. The results of this study suggest that combined information on SOD and CAT activities together with LPO levels in the liver could be a useful indicator for assessing oxidative stress in freshwater fish. PMID:24477393

  8. Involvement of the Antioxidant Effect and Anti-inflammatory Response in Butyrate-Inhibited Vascular Smooth Muscle Cell Proliferation

    PubMed Central

    Mathew, Omana P.; Ranganna, Kasturi; Milton, Shirlette G.

    2014-01-01

    Epigenetic mechanisms by altering the expression and, in turn, functions of target genes have potential to modify cellular processes that are characteristics of atherosclerosis, including inflammation, proliferation, migration and apoptosis/cell death. Butyrate, a natural epigenetic modifier and a histone deacetylase inhibitor (HDACi), is an inhibitor of vascular smooth muscle cell (VSMC) proliferation, a critical event in atherogenesis. Here, we examined whether glutathione peroxidases (GPxs), a family of antioxidant enzymes, are modulated by butyrate, contributing to its antiproliferation action on VSMC through the regulation of the inflammatory response by using western blotting, immunostaining methods and activity assay. Treatment of VSMC with butyrate not only upregulates glutathione peroxidase (GPx) 3 and GPx4, but also increases the overall catalytic activity of GPx supporting involvement of antioxidant effect in butyrate arrested VSMC proliferation. Moreover, analysis of the redox-sensitive NF-κB transcription factor system, the target of GPx, reveals that butyrate causes downregulation of IKKα, IKKβ, IkBα and NF-κBp65 expression and prevents NF-κBp65 phosphorylation at serine536 causing inhibition of the expression NF-κB target inflammatory genes, including inducible nitric oxide synthase, VCAM-1 and cyclooxygenase-2. Overall, these observations suggest a link between the antioxidant effect and anti-inflammatory response in butyrate-arrested VSMC proliferation, accentuating the atheroprotective and therapeutic potential of natural products, like butyrate, in vascular proliferative diseases. PMID:25390157

  9. The effects of prenatal methylmercury exposure on trace element and antioxidant levels in rats following 6-hydroxydopamine-induced neuronal insult.

    PubMed

    Mohamed Moosa, Zulfiah; Daniels, Willie M U; Mabandla, Musa V

    2014-06-01

    Methylmercury (MeHg) is a metal toxin found commonly in the environment. Studies have shown severe neurotoxic effects of MeHg poisoning especially during pregnancy where it crosses the foetoplacental and the blood brain barrier of the foetus leading to neurodevelopmental deficits in the offspring. These deficits may predispose offspring to neurodegenerative diseases later in life. In this study we investigated the effects of prenatal methylmercury exposure (2.5 mg/L in drinking water from GND 1-GND 21) on the trace element status in the brain of adolescent offspring (PND 28). Total antioxidant capacity (TAC) was measured in their blood plasma. In a separate group of animals that was also exposed prenatally to MeHg, 6-hydroydopamine (6-OHDA) was administered at PND 60 as a model of neuronal insult. Trace element and TAC levels were compared before and after 6-OHDA exposure. Prenatal MeHg treatment alone resulted in significantly higher concentrations of zinc, copper, manganese and selenium in the brain of offspring at PND 28 (p < 0.05), when compared to controls. In contrast, brain iron levels in MeHg-exposed adolescent offspring were significantly lower than their controls (p < 0.05). Following 6-OHDA exposure, the levels of iron, zinc, copper and manganese were increased compared to sham-lesioned offspring (p < 0.05). Prenatal MeHg exposure further increased these trace element levels thereby promoting toxicity (p < 0.05). Total antioxidant capacity was not significantly different in MeHg and control groups prior to lesion. However, following 6-OHDA administration, MeHg-exposed animals had a significantly lower TAC than that of controls (p < 0.05). Brain TAC levels were higher in adult male rats than in female rats during adolescence however male rats that had been exposed to MeHg in utero failed to show this increase at PND 74. Prenatal MeHg exposure results in trace element dyshomeostasis in the brain of offspring and reduces total

  10. Changes in plant communities along soil pollution gradients: responses of leaf antioxidant enzyme activities and phytochelatin contents.

    PubMed

    Dazy, Marc; Béraud, Eric; Cotelle, Sylvie; Grévilliot, Frédérique; Férard, Jean-François; Masfaraud, Jean-François

    2009-10-01

    This work describes an ecological and ecotoxicological study of polluted wasteland plant communities in a former coke-factory located in Homécourt (France). Ecological analyses were performed along two transects to investigate changes in plant community structure through species richness (S), biological diversity (H') and evenness (J). Five species (Arrhenatherum elatius, Bromus tectorum, Euphorbia cyparissias, Hypericum perforatum and Tanacetum vulgare) were then selected to assess cellular responses through antioxidant enzyme activities and phytochelatins (PCs) contents. The results showed that species richness and biological diversity correlated negatively to Cd and Hg concentrations in soil suggesting that soil concentration of non-essential heavy metals was the primary factor governing vegetation structure in the industrial wasteland. Moreover, for all studied species, abundances were partly related to metal levels in the soils, but also to plant antioxidant systems, suggesting their role in plant establishment success in polluted areas. Data for PC contents led to less conclusive results.

  11. Involvement of an antioxidant defense system in the adaptive response to cadmium in maize seedlings (Zea mays L.).

    PubMed

    Xu, Xianghua; Liu, Cuiying; Zhao, Xiaoyan; Li, Renying; Deng, Wenjing

    2014-11-01

    Chemical and biological analyses were used to investigate the growth response and antioxidant defense mechanism of maize seedlings (Zea mays L.) grown in soils with 0-100 mg kg(-1) Cd. Results showed that maize seedlings have strong abilities to accumulate and tolerate high concentrations of Cd. For soil with 50 mg kg(-1) Cd, the Cd contents in roots and shoots of maize seedlings are as large as 295.6 and 153.0 mg kg(-1) DW, respectively, without visible symptoms of toxicity. Lower soil Cd concentrations lead to a decrease in reduced glutathione (GSH) content in leaves of maize seedlings, whereas higher soil Cd concentrations resulted in an increase in the activities of superoxide dismutase, guaiacol peroxidase, catalase, and ascorbate peroxidase. Maize seedlings have strong capacities to adapt to low concentrations of Cd by consuming GSH and to develop an antioxidative enzyme system to defend against high-Cd stress.

  12. Antioxidative and immunological responses in the haemolymph of wolf spider Xerolycosa nemoralis (Lycosidae) exposed to starvation and dimethoate.

    PubMed

    Stalmach, Monika; Wilczek, Grażyna; Homa, Joanna; Szulinska, Elżbieta

    2015-11-01

    The aim of this study was to assess the intensity of enzymatic antioxidative parameters [catalase (CAT), glutathione peroxidase (GSTPx), glutathione reductase (GR), total antioxidant capacity (TAC)] and percentage of high granularity cells as well as low to medium granularity cells in haemolymph of wolf spiders Xerolycosa nemoralis exposed to starvation and dimethoate under laboratory conditions. Only in starved males, haemolymph included a lower percentage of high granularity cells, accompanied by high activity of CAT and GSTPx, than in the control. Exposure of males to dimethoate increased CAT activity, after single application, and significantly enhanced GR activity, after five-time application. In females, five-time contact with dimethoate elevated the percentage of high granularity cells. As in comparison to females, male X. nemoralis were more sensitive to the applied stressing factors, it may be concluded that in natural conditions both food deficiency and chemical stress may diminish the immune response of their organisms.

  13. Oxidative stress and antioxidant status response of handball athletes: implications for sport training monitoring.

    PubMed

    Marin, Douglas Popp; Bolin, Anaysa Paola; Campoio, Thais Regina; Guerra, Beatriz Alves; Otton, Rosemari

    2013-10-01

    The chronic exposure to regular exercise training seems to improve antioxidant defense systems. However, the intense physical training imposed on elite athletes may lead to overtraining associated with oxidative stress. The purpose of the present study was to investigate the effect of different training loads and competition on oxidative stress, biochemical parameters and antioxidant enzymatic defense in handball athletes during 6-months of monitoring. Ten male elite handball athletes were recruited to the study. Blood samples were collected four times every six weeks throughout the season. During most intense periods of training and competitions there were significant changes in plasma indices of oxidative stress (increased TBARS and decreased thiols). Conversely, chronic adaptations to exercise training demonstrated a significant protective effect against oxidative stress in erythrocyte (decrease in TBARs and carbonyl group levels). Erythrocyte antioxidant enzyme activities were significantly increased, suggesting a training-induced antioxidant adaptation. Biomarkers of skeletal muscle damage were significantly increased during high-intensity training period (creatine kinase, lactate dehydrogenase and aspartate aminotransferase). No significant changes were observed in plasma IL-6, TNF-α and uric acid, whereas a significant reduction was found in the IL-1β concentration and gamma-glutamyl transferase activity. Oxidative stress and antioxidant biomarkers can change throughout the season in competitive athletes, reflecting the physical stress and muscle damage that occurs as the result of competitive handball training. In addition, these biochemical measurements can be applied in the physiological follow-up of athletes.

  14. Boron influences immune and antioxidant responses by modulating hepatic superoxide dismutase activity under calcium deficit abiotic stress in Wistar rats.

    PubMed

    Bhasker, T Vijay; Gowda, N K S; Mondal, S; Krishnamoorthy, P; Pal, D T; Mor, A; Bhat, S Karthik; Pattanaik, A K

    2016-07-01

    The influence of Boron (B) supplementation on immune and antioxidant status of rats with or without abiotic stress induced by dietary calcium (Ca) restriction was studied in a feeding trial of 90 days. Wistar strain rats (3-4 wk age, n=84) were divided into 7 dietary groups (4 replicates of 3 each) viz., normal-calcium (100%) basal diet alone (NC, control) or supplemented with B at 5 (NCB-5), 10 (NCB-10), 20 (NCB-20) and 40ppm (NCB-40) levels; low-calcium (50%) basal diet alone (LC) or supplemented with 40ppm B (LCB-40). After 75 days of experimental feeding, rats were challenged with intraperitoneal injection of sheep RBCs to assess their humoral immunity. At the end of the trial, cell-mediated immunity was assessed as foot pad reaction to sheep RBCs injected into the hind leg paws. Eight rats from each group were sacrificed to collect blood for estimation of minerals and total antioxidant activity, and liver for superoxide dismutase gene expression analysis. Supplementation of graded levels of B (5, 10, 20 and 40ppm) as borax in NC diets significantly increased (P<0.01) the footpad thickness and serum total antioxidant activity, hepatic expression levels of both Cu-Zn SOD (SOD1) and Mn-SOD (SOD2) mRNAs. The erythrocytic SOD activity and humoral response did not differ significantly among the dietary groups. In Ca restricted groups, humoral immune response was significantly decreased (P<0.01) compared to control but increased (P<0.05) with 40ppm B supplementation. Serum levels of copper (Cu) and zinc (Zn) remained similar among the dietary groups, while the manganese (Mn) content was significantly decreased (P<0.01) with increased levels of dietary B. In conclusion, B supplementation increased the hepatic mRNA expression levels of both SOD isoenzymes, thereby improving the immune and antioxidant status. PMID:27259355

  15. 33 CFR Appendix D to Part 154 - Training Elements for Oil Spill Response Plans

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 33 Navigation and Navigable Waters 2 2013-07-01 2013-07-01 false Training Elements for Oil Spill... Appendix D to Part 154—Training Elements for Oil Spill Response Plans 1. General 1.1The portion of the plan... contracted oil spill removal organizations and the procedures to notify the activate such organizations....

  16. 33 CFR Appendix D to Part 154 - Training Elements for Oil Spill Response Plans

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 33 Navigation and Navigable Waters 2 2014-07-01 2014-07-01 false Training Elements for Oil Spill... Appendix D to Part 154—Training Elements for Oil Spill Response Plans 1. General 1.1The portion of the plan... contracted oil spill removal organizations and the procedures to notify the activate such organizations....

  17. 33 CFR Appendix D to Part 154 - Training Elements for Oil Spill Response Plans

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 33 Navigation and Navigable Waters 2 2012-07-01 2012-07-01 false Training Elements for Oil Spill... Appendix D to Part 154—Training Elements for Oil Spill Response Plans 1. General 1.1The portion of the plan... contracted oil spill removal organizations and the procedures to notify the activate such organizations....

  18. 33 CFR Appendix D to Part 154 - Training Elements for Oil Spill Response Plans

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ....14Occupational Safety and Health Administration requirements for worker health and safety (29 CFR 1910.120). 3... 33 Navigation and Navigable Waters 2 2010-07-01 2010-07-01 false Training Elements for Oil Spill... Appendix D to Part 154—Training Elements for Oil Spill Response Plans 1. General 1.1The portion of the...

  19. 33 CFR Appendix C to Part 155 - Training Elements for Oil Spill Response Plans

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... worker health and safety (29 CFR 1910.120). 3. Further Considerations In drafting the training section of... 33 Navigation and Navigable Waters 2 2011-07-01 2011-07-01 false Training Elements for Oil Spill.... 155, App. C Appendix C to Part 155—Training Elements for Oil Spill Response Plans 1. General...

  20. 33 CFR Appendix D to Part 154 - Training Elements for Oil Spill Response Plans

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ....14Occupational Safety and Health Administration requirements for worker health and safety (29 CFR 1910.120). 3... 33 Navigation and Navigable Waters 2 2011-07-01 2011-07-01 false Training Elements for Oil Spill... Appendix D to Part 154—Training Elements for Oil Spill Response Plans 1. General 1.1The portion of the...

  1. Endogenous antioxidants and nasal human epithelium response to air pollutants: genotoxic and inmmuno-cytochemical evaluation.

    PubMed

    Fortoul, T I; Rojas-Lemus, M; Avila-Casado, M C; Rodriguez-Lara, V; Montaño, L F; Muñoz-Comonfort, A; Lopez-Zepeda, L S

    2010-10-01

    Nasal epithelium is a source for identifying atmospheric pollution impact. Antioxidants play a relevant role in the protection of the cells from environmental injury, but scarce information is available about the interaction of endogenous antioxidants and genotoxic damage in nasal epithelium from urban populations highly exposed to traffic-generated air pollutants. An immunocytochemical and genotoxic evaluation was implemented in nasal cell epithelium in a population chronically exposed to atmospheric pollution from autumn 2004 to autumn 2005. Superoxide dismutase (SOD) and Catalase (CAT) were evaluated in nasal scrapings by morphometry and genotoxicity by comet assay. An increase in DNA damage correlates with a decrease in SOD and CAT in nasal cells during autumn and the inverse result was observed during summer (R = 0.88). Not only should exogenous antioxidant supplements be encouraged, but also a healthy diet to strengthen intracellular defenses against oxidative stress induced by exposure to air pollutants. PMID:20981858

  2. Impact of tributyltin on antioxidant and DNA damage response in spermatozoa of freshwater prawn Macrobrachium rosenbergii.

    PubMed

    Rani, K Umaa; Musthafa, M Saiyad; War, Mehrajuddin; Al-Sadoon, Mohammad K; Paray, Bilal Ahmad; Shareef, T H Mohamed Ahadhu; Nawas, P Mohideen Askar

    2015-12-01

    Effects of tributyltin (TBT) on antioxidant [total superoxide dismutase (SOD), glutathione peroxidase (GPx), and glutathione reductase (GR)] and DNA damage levels in the spermatozoa were studied and reported here for the first time in the freshwater prawn Macrobrachium rosenbergii. Three groups of (n = 10 in each group) fishes were exposed to three different nominal concentrations of TBT viz., 1, 2, and 4 mg L(-1) along with control group for 90 days. Significant decrease of antioxidant and increased DNA damage levels were seen at higher doses of 2 and 4 mg L(-1). In prawn, the antioxidant level plays a vital role in sperm protection, activation, differential functions related to the physiology, and reproductive behavior. This study serves as a biomonitoring tool to assess the TBT effects on reproductive behavior of aquatic biota.

  3. Antioxidant responses in clam Venerupis philippinarum exposed to environmental pollutant hexabromocyclododecane.

    PubMed

    Zhang, Hui; Pan, Luqing; Tao, Yanxia

    2014-01-01

    The objective of this study was to assess the potential toxic effects of hexabromocyclododecane (HBCD) on tissues of clam Venerupis philippinarum using parameters of antioxidant defenses and oxidative stress. Antioxidant biomarkers including ethoxyresorufin-O-deethylase (EROD), glutathione S-transferase (GST), superoxide dismutase (SOD), and glutathione (GSH), as well as DNA damage and lipid peroxidation (LPO) in gills and digestive glands of V. philippinarum, were analyzed after a 1-, 3-, 6-, 10-, and 15-day exposure to seawater containing HBCD at environmentally related concentrations, respectively. The results showed that the activity of most antioxidant enzymes increased, and different trends were detected with exposure time extending. The oxidative stress could be obviously caused in the gills and digestive glands under the experimental conditions. This could provide useful information for toxic risk assessment of environmental pollutant HBCD.

  4. Lipid peroxidation and antioxidant responses in zebrafish brain induced by Aphanizomenon flos-aquae DC-1 aphantoxins.

    PubMed

    Zhang, De Lu; Hu, Chun Xiang; Li, Dun Hai; Liu, Yong Ding

    2013-11-15

    Aphanizomenon flos-aquae is a cyanobacterium that is frequently encountered in eutrophic waters worldwide. It is source of neurotoxins known as aphantoxins or paralytic shellfish poisons (PSPs), which present a major threat to the environment and human health. The molecular mechanism of PSP action is known, however the in vivo effects of this neurotoxin on oxidative stress, lipid peroxidation and the antioxidant defense responses in zebrafish brain remain to be understood. Aphantoxins purified from a natural isolate of A. flos-aquae DC-1 were analyzed using high performance liquid chromatography. The major components of the toxins were gonyautoxins 1 and 5 (GTX1 and GTX5, 34.04% and 21.28%, respectively) and neosaxitoxin (neoSTX, 12.77%). Zebrafish (Danio rerio) were injected intraperitoneally with 7.73 μg/kg (low dose) and 11.13 μg/kg (high dose) of A. flos-aquae DC-1 aphantoxins. Oxidative stress, lipid peroxidation and antioxidant defense responses in the zebrafish brain were investigated at various timepoints at 1-24h post-exposure. Aphantoxin exposure was associated with significantly increased (>1-2 times) reactive oxygen species (ROS) and malondialdehyde (MDA) in zebrafish brain compared with the controls at 1-12h postexposure, suggestive of oxidative stress and lipid peroxidation. In contrast, reduced glutathione (GSH) levels in the zebrafish brain exposed to high or low doses of aphantoxins decreased by 44.88% and 41.33%, respectively, after 1-12h compared with the controls, suggesting that GSH participated in detoxification to ROS and MDA. Further analysis showed a significant increase in the activities of superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GPx) compared with the controls, suggesting elimination of oxidative stress by the antioxidant response in zebrafish brain. All these changes were dose and time dependent. These results suggested that aphantoxins or PSPs increased ROS and MDA and decreased GSH in zebrafish brain

  5. Effects of vitamin C and E supplementation on endogenous antioxidant systems and heat shock proteins in response to endurance training

    PubMed Central

    Cumming, Kristoffer T.; Raastad, Truls; Holden, Geir; Bastani, Nasser E.; Schneeberger, Damaris; Paronetto, Maria Paola; Mercatelli, Neri; Østgaard, Hege N.; Ugelstad, Ingrid; Caporossi, Daniela; Blomhoff, Rune; Paulsen, Gøran

    2014-01-01

    Abstract Reactive oxygen and nitrogen species are important signal molecules for adaptations to training. Due to the antioxidant properties of vitamin C and E, supplementation has been shown to blunt adaptations to endurance training. In this study, we investigated the effects of vitamin C and E supplementation and endurance training on adaptations in endogenous antioxidants and heat shock proteins (HSP). Thirty seven males and females were randomly assigned to receive Vitamin C and E (C + E; C: 1000 mg, E: 235 mg daily) or placebo (PLA), and underwent endurance training for 11 weeks. After 5 weeks, a subgroup conducted a high intensity interval session to investigate acute stress responses. Muscle and blood samples were obtained to investigate changes in proteins and mRNA related to the antioxidant and HSP system. The acute response to the interval session revealed no effects of C + E supplementation on NFκB activation. However, higher stress responses to exercise in C + E group was indicated by larger translocation of HSPs and a more pronounced gene expression compared to PLA. Eleven weeks of endurance training decreased muscle GPx1, HSP27 and αB‐crystallin, while mnSOD, HSP70 and GSH remained unchanged, with no influence of supplementation. Plasma GSH increased in both groups, while uric acid decreased in the C + E group only. Our results showed that C + E did not affect long‐term training adaptations in the antioxidant‐ and HSP systems. However, the greater stress responses to exercise in the C + E group might indicate that long‐term adaptations occurs through different mechanisms in the two groups. PMID:25293598

  6. Optimization of Extraction Conditions for Maximal Phenolic, Flavonoid and Antioxidant Activity from Melaleuca bracteata Leaves Using the Response Surface Methodology.

    PubMed

    Hou, Wencheng; Zhang, Wei; Chen, Guode; Luo, Yanping

    2016-01-01

    Melaleuca bracteata is a yellow-leaved tree belonging to the Melaleuca genus. Species from this genus are known to be good sources of natural antioxidants, for example, the "tea tree oil" derived from M. alternifolia is used in food processing to extend the shelf life of products. In order to determine whether M. bracteata contains novel natural antioxidants, the components of M. bracteata ethanol extracts were analyzed by gas chromatography-mass spectrometry. Total phenolic and flavonoid contents were extracted and the antioxidant activities of the extracts evaluated. Single-factor experiments, central composite rotatable design (CCRD) and response surface methodology (RSM) were used to optimize the extraction conditions for total phenolic content (TPC) and total flavonoid content (TFC). Ferric reducing power (FRP) and 1,1-Diphenyl-2-picrylhydrazyl radical (DPPH·) scavenging capacity were used as the evaluation indices of antioxidant activity. The results showed that the main components of M. bracteata ethanol extracts are methyl eugenol (86.86%) and trans-cinnamic acid methyl ester (6.41%). The single-factor experiments revealed that the ethanol concentration is the key factor determining the TPC, TFC, FRP and DPPH·scavenging capacity. RSM results indicated that the optimal condition of all four evaluation indices was achieved by extracting for 3.65 days at 53.26°C in 34.81% ethanol. Under these conditions, the TPC, TFC, FRP and DPPH·scavenging capacity reached values of 88.6 ± 1.3 mg GAE/g DW, 19.4 ± 0.2 mg RE/g DW, 2.37 ± 0.01 mM Fe2+/g DW and 86.0 ± 0.3%, respectively, which were higher than those of the positive control, methyl eugenol (FRP 0.97 ± 0.02 mM, DPPH·scavenging capacity 58.6 ± 0.7%) at comparable concentrations. Therefore, the extracts of M. bracteata leaves have higher antioxidant activity, which did not only attributed to the methyl eugenol. Further research could lead to the development of a potent new natural antioxidant. PMID

  7. Optimization of Extraction Conditions for Maximal Phenolic, Flavonoid and Antioxidant Activity from Melaleuca bracteata Leaves Using the Response Surface Methodology

    PubMed Central

    Hou, Wencheng; Zhang, Wei; Chen, Guode; Luo, Yanping

    2016-01-01

    Melaleuca bracteata is a yellow-leaved tree belonging to the Melaleuca genus. Species from this genus are known to be good sources of natural antioxidants, for example, the “tea tree oil” derived from M. alternifolia is used in food processing to extend the shelf life of products. In order to determine whether M. bracteata contains novel natural antioxidants, the components of M. bracteata ethanol extracts were analyzed by gas chromatography–mass spectrometry. Total phenolic and flavonoid contents were extracted and the antioxidant activities of the extracts evaluated. Single-factor experiments, central composite rotatable design (CCRD) and response surface methodology (RSM) were used to optimize the extraction conditions for total phenolic content (TPC) and total flavonoid content (TFC). Ferric reducing power (FRP) and 1,1-Diphenyl-2-picrylhydrazyl radical (DPPH·) scavenging capacity were used as the evaluation indices of antioxidant activity. The results showed that the main components of M. bracteata ethanol extracts are methyl eugenol (86.86%) and trans-cinnamic acid methyl ester (6.41%). The single-factor experiments revealed that the ethanol concentration is the key factor determining the TPC, TFC, FRP and DPPH·scavenging capacity. RSM results indicated that the optimal condition of all four evaluation indices was achieved by extracting for 3.65 days at 53.26°C in 34.81% ethanol. Under these conditions, the TPC, TFC, FRP and DPPH·scavenging capacity reached values of 88.6 ± 1.3 mg GAE/g DW, 19.4 ± 0.2 mg RE/g DW, 2.37 ± 0.01 mM Fe2+/g DW and 86.0 ± 0.3%, respectively, which were higher than those of the positive control, methyl eugenol (FRP 0.97 ± 0.02 mM, DPPH·scavenging capacity 58.6 ± 0.7%) at comparable concentrations. Therefore, the extracts of M. bracteata leaves have higher antioxidant activity, which did not only attributed to the methyl eugenol. Further research could lead to the development of a potent new natural antioxidant. PMID

  8. Mineral elements, lipoxygenase activity, and antioxidant capacity of okara as a byproduct in hydrothermal processing of soy milk.

    PubMed

    Stanojevic, Sladjana P; Barac, Miroljub B; Pesic, Mirjana B; Zilic, Sladjana M; Kresovic, Mirjana M; Vucelic-Radovic, Biljana V

    2014-09-10

    Minerals and antioxidative capacity of raw okara that was obtained as a byproduct from six soybean varieties during hydrothermal cooking (HTC) of soy milk were assessed. Lipoxygenase (Lox), an enzyme deteriorating the sensory characteristics of okara, was also investigated. All genotypes had very similar concentrations of Lox (4.32-5.62%). Compared to raw soybeans, the applied HTC significantly reduced Lox content in okara (0.54-0.19%) and lowered its activity to 0.004-0.007 μmol g(-1) min (-1). Correlation between the content of Lox in soybeans and that in okara (r = 0.21;p < 0.05) was not registered. This indicates that the content of this enzyme in okara depended much more on the technological process than on soybean genotype. Very strong correlation (r = 0.99; p < 0.05) between okara Lox content and its activity was found. The most abundant minerals in raw okara were potassium (1.04-1.21 g/100g), phosphorus (0.45-0.50 g/100 g), calcium (0.26-0.39 g/100 g), and iron (5.45-10.95 mg/100 g). A very high antioxidant capacity (19.06-29.36 mmol Trolox kg(-1)) contributes to the nutritional value of raw okara. PMID:25167333

  9. Hormone response element binding proteins: novel regulators of vitamin D and estrogen signaling

    PubMed Central

    Lisse, Thomas S.; Hewison, Martin; Adams, John S.

    2011-01-01

    Insights from vitamin D-resistant New World primates and their human homologues as models of natural and pathological insensitivity to sterol/steroid action have uncovered a family of novel intracellular vitamin D and estrogen regulatory proteins involved in hormone action. The proteins, known as “vitamin D or estrogen response element-binding proteins”, behave as potent cis-acting, transdominant regulators to inhibit steroid receptor binding to DNA response elements and is responsible for vitamin D and estrogen resistances. This set of interactors belongs to the heterogeneous nuclear ribonucleoprotein (hnRNP) family of previously known pre-mRNA-interacting proteins. This review provides new insights into the mechanism by which these novel regulators of signaling and metabolism can act to regulate responses to vitamin D and estrogen. In addition the review also describes other molecules that are known to influence nuclear receptor signaling through interaction with hormone response elements. PMID:21236284

  10. Non-cytotoxic concentrations of acetaminophen induced mitochondrial biogenesis and antioxidant response in HepG2 cells.

    PubMed

    Zhang, Tingfen; Zhang, Qiang; Guo, Jiabin; Yuan, Haitao; Peng, Hui; Cui, Lan; Yin, Jian; Zhang, Li; Zhao, Jun; Li, Jin; White, Andrew; Carmichael, Paul L; Westmoreland, Carl; Peng, Shuangqing

    2016-09-01

    Mitochondrial dysfunction has been implicated in acute, severe liver injury caused by overdose of acetaminophen (APAP). However, whether mitochondrial biogenesis is involved is unclear. Here we demonstrated that mitochondrial biogenesis, as indicated by the amounts of mitochondrial DNA and proteins, increased significantly in HepG2 cells exposed to low, non-cytotoxic concentrations of APAP. This heightened response was accompanied by upregulated expression of PGC-1α, NRF-1 and TFAM, which are key transcriptional regulators of mitochondrial biogenesis. Additionally, antioxidants including glutathione, MnSOD, HO-1, NQO1, and Nrf2 were also significantly upregulated. In contrast, for HepG2 cells exposed to high, cytotoxic concentration of APAP, mitochondrial biogenesis was inhibited and the expression of its regulatory proteins and antioxidants were concentration-dependently downregulated. In summary, our study indicated that mitochondrial biogenesis, along with antioxidant induction, may be an important cellular adaptive mechanism counteracting APAP-induced toxicity and overwhelming this cytoprotective capacity could result in liver injury. PMID:27438896

  11. Antioxidative responses in females and males of the spider Xerolycosa nemoralis (Lycosidae) exposed to natural and anthropogenic stressors.

    PubMed

    Wilczek, Grażyna; Babczyńska, Agnieszka; Wilczek, Piotr

    2013-03-01

    The aim of this study was to assess the intensity of enzymatic antioxidative parameters [i.e., superoxide dismutase (SOD), catalase (CAT), and the glutathione peroxidases each selene dependent, GPOX or selene independent, including GSTPx, glutathione S-transferase, and GST] and non-enzymatic antioxidative parameters [i.e., glutathione total (GSH-t), the heat shock proteins of Hsp70, and metallothioneins (Mt)] in the midgut glands of female and male wolf spiders Xerolycosa nemoralis (Lycosidae) exposed to natural stressors (i.e., heat shock and starvation) and anthropogenic stressors (i.e., the organophosphorous pesticide dimethoate) under laboratory conditions. The spiders were collected from two differentially polluted sites both localized in southern Poland: Olkusz, which is heavily polluted with metals, and Pilica, the reference site. In response to the stressing factors, increases in Hsp70 levels, in the concentrations of total glutathione and in the activity levels of glutathione-dependent enzymes (GPOX, GSTPx, and GST) were found in the midgut glands of males. In the females, high levels of activity of CAT and SOD were revealed, as well as an increased percentage of Mt-positive cells. Preexposed females, in comparison to the individuals from the reference site, responded with increased SOD activity, irrespective of the stressing factor. In contrast, the changes in the antioxidative parameters in the midgut glands of male X. nemoralis seem to reflect a short-term reaction to the applied stressors and do not confirm the effects of long-term selection in a polluted environment.

  12. Potential of Hydrocotyle vulgaris for phytoremediation of a textile dye: Inducing antioxidant response in roots and leaves.

    PubMed

    Vafaei, F; Movafeghi, A; Khataee, A R; Zarei, M; Salehi Lisar, S Y

    2013-07-01

    The potential of Hydrocotyle vulgaris as an aquatic plant species was evaluated for phytoremediation of C.I. Basic Red 46 (BR46) from nutrient solution. Under the optimized experimental conditions, BR46 was removed up to 95% from incubation medium by H. vulgaris. The ability of the plant in consecutive removal under long term repetitive experiments confirmed the biodegradation process. Accordingly, a number of produced intermediate compounds were identified. An artificial neural network (ANN) model was developed to predict the biodegradation efficiency. A predictive performance (R(2)=0.974) was obtained based on the network results. Interestingly, dye stress enhanced the activity of antioxidant enzymes including superoxide dismutase, peroxidase and catalase in H. vulgaris roots and leaves. Enzymatic responses found to be highly depended on the plant organ and dye concentration in the liquid medium. Overall, the increase in the activity of antioxidant enzymes was much higher in the roots than in the leaves. Nevertheless, no significant increase in the malondialdehyde (MDA) content was detected in both roots and leaves which reflects the high efficiency of antioxidant system in the elimination of reactive oxygen species.

  13. Antioxidant response in liver of the phytoplanktivorous bighead carp (Aristichthys nobilis) intraperitoneally-injected with extracted microcystins.

    PubMed

    Li, Li; Xie, Ping; Guo, Longgen

    2010-06-01

    The worldwide occurrence of cyanobacterial blooms makes it necessary to perform environmental risk assessment procedures to monitor the effects of microcystins (MCs) on fish. Oxidative stress biomarkers are valuable tools in this regard. In the present study, phytoplanktivorous bighead carp (Aristichthys nobilis) were injected intraperitoneally (i.p.) with extracted MCs (mainly MC-RR and -LR) at two doses, 400 and 1,000 microg kg(-1) bw, and antioxidant responses of the liver as biomarkers of oxygen-mediated toxicity were studied at 1, 3, 12, 24 and 48 h after injection. Contents of reactive oxygen species (ROS) and activities of antioxidant enzymes [catalase (CAT), superoxide dismutase (SOD), glutathione peroxide (GPX), and glutathione reductase (GR)] as well as glutathione S-transferase (GST) in the liver in both dose groups showed a biphasic change with an increase at initial 3 h followed by a decrease after injection, owing to the roles of the antioxidant system in eliminating excessive ROS and regenerating glutathione (GSH). The increased GST was probably due to the high transcription of cytosolic GST alpha and rho, suggesting the importance of MCs detoxification by GSH pathway. The stable GSH levels in liver may be explained by the high basic GSH concentration in liver, and/or an increased GSH synthesis, suggesting a high ability to detoxify MCs and to release associated high oxidative pressure in phytoplantivorous fish. PMID:20467858

  14. Sublethal toxicity of carbofuran on the African catfish Clarias gariepinus: Hormonal, enzymatic and antioxidant responses.

    PubMed

    Ibrahim, Ahmed Th A; Harabawy, Ahmed S A

    2014-08-01

    The present study examined the impacts of carbofuran on endocrinology of the catfish, Clarias gariepinus, for the first time and evaluated cortisol (CRT), triiodothyronine (T3), thyroxin (T4), 17β-estradiol (E2) and testosterone (TST) and the oxidative stress markers including SOD, CAT, GSTs, GSH. The toxic effects on the metabolic enzymes, G6PDH and LDH, in addition to lipid peroxidation (LPO) and DNA damage as biomarkers in Nile catfish, to sublethal exposures of carbofuran (0.16 and 0.49mg/L, for 35 days) were studied. Statistically significant differences between selected parameters between control and carbofuran-treated fish were recorded. Carbofuran caused a significant (p<0.05) increase in CRT and T3 levels; the mean levels of T4, TST, E2 exhibited significant decreases (p<0.05) in carbofuran-treated fish. Toxicity of carbofuran on liver, kidney, gills, gonads and muscles after 35 days of exposure was found. Glycogen levels showed a highly significant decrease in liver and gills (p< 0.001), a significant decrease (p< 0.05) in kidney and muscles, and insignificant changes (p>0.05) in gonads of treated fish. The two metabolic enzymes G6PDH and LDH in all tissues exhibited significant decreases (p<0.05) in treated fish. SOD, CAT, GSH and GST levels showed significant decreases (p<0.05) in all tissues of fish after exposure to carbofuran. LPO levels increased significantly (p<0.05) in all tissues except gonads after 5 weeks of exposure to carbofuran. There was a significant (p<0.05) increase in DNA fragmentation percentage in treated fish. Our results provide a clear evidence on the response of C. gariepinus to sublethal doses of carbofuran and allow us to consider catfish as a good bioindicator to reflect the endocrine disrupting impacts of carbofuran, and reflect the potential of this pesticide to cause disturbance in antioxidant defense system as well as metabolism and induction of lipid peroxidation (LPO) and DNA damage in contaminated ecosystems.

  15. Heterogeneous Role of the Glutathione Antioxidant System in Modulating the Response of ESFT to Fenretinide in Normoxia and Hypoxia

    PubMed Central

    Magwere, Tapiwanashe; Burchill, Susan A.

    2011-01-01

    Glutathione (GSH) is implicated in drug resistance mechanisms of several cancers and is a key regulator of cell death pathways within cells. We studied Ewing's sarcoma family of tumours (ESFT) cell lines and three mechanistically distinct anticancer agents (fenretinide, doxorubicin, and vincristine) to investigate whether the GSH antioxidant system is involved in the reduced sensitivity to these chemotherapeutic agents in hypoxia. Cell viability and death were assessed by the trypan blue exclusion assay and annexin V-PI staining, respectively. Hypoxia significantly decreased the sensitivity of all ESFT cell lines to fenretinide-induced death, whereas the effect of doxorubicin or vincristine was marginal and cell-line-specific. The response of the GSH antioxidant system in ESFT cell lines to hypoxia was variable and also cell-line-specific, although the level of GSH appeared to be most dependent on de novo biosynthesis rather than recycling. RNAi-mediated knockdown of key GSH regulatory enzymes γ-glutamylcysteine synthetase or glutathione disulfide reductase partially reversed the hypoxia-induced resistance to fenretinide, and increasing GSH levels using N-acetylcysteine augmented the hypoxia-induced resistance in a cell line-specific manner. These observations are consistent with the conclusion that the role of the GSH antioxidant system in modulating the sensitivity of ESFT cells to fenretinide is heterogeneous depending on environment and cell type. This is likely to limit the value of targeting GSH as a therapeutic strategy to overcome hypoxia-induced drug resistance in ESFT. Whether targeting the GSH antioxidant system in conjunction with other therapeutics may benefit some patients with ESFT remains to be seen. PMID:22174837

  16. Glyphosate-based herbicide exposure causes antioxidant defence responses in the fruit fly Drosophila melanogaster.

    PubMed

    de Aguiar, Lais Mattos; Figueira, Fernanda Hernandes; Gottschalk, Marco Silva; da Rosa, Carlos Eduardo

    2016-01-01

    Glyphosate is a non-selective and post-emergent herbicide that affects plant growth. Animal exposure to this herbicide can lead to adverse effects, such as endocrine disruption, oxidative stress and behavioural disorders. Drosophilids have been utilized previously as an effective tool in toxicological tests. In the present study, the effects of a glyphosate-based herbicide (Roundup [Original]) were investigated regarding oxidative stress, the antioxidant defence system and acetylcholinesterase (AChE) activity in Drosophila melanogaster. Flies (of both genders) that were 1 to 3days old were exposed to different glyphosate concentrations (0.0mg/L=control, 1.0mg/L, 2.0mg/L, 5.0mg/L and 10.0mg/L) in the diet for 24h and 96h. After the exposure periods, reactive oxygen species (ROS) levels, antioxidant capacity against peroxyl radicals (ACAP) and lipid peroxidation (LPO) levels were quantified. In addition, the mRNA expression of antioxidant genes (i.e., keap1, sod, sod2, cat, irc, gclc, gclm, gss, trxt, trxr-1 and trxr-2) was evaluated via RT-PCR. Additionally, AChE activity was evaluated only after the 96h exposure period. The results indicated that Roundup exposure leads to a reduction in ROS levels in flies exposed for 96h. ACAP levels and gene expression of the antioxidant defence system exhibited an increase from 24h, while LPO did not show any significant alterations in both exposure periods. AChE activity was not affected following Roundup exposure. Our data suggest that Roundup exposure causes an early activation of the antioxidant defence system in D. melanogaster, and this can prevent subsequent damage caused by ROS.

  17. Antioxidant and oxidative stress responses of sojourners at high altitude in different climatic temperatures

    NASA Astrophysics Data System (ADS)

    Sinha, Sanchari; Singh, Som Nath; Saha, Mantu; Kain, T. C.; Tyagi, A. K.; Ray, Uday Sankar

    2010-01-01

    High altitude (HA) is a multi-stressor environment comprising hypobaric hypoxia and cold. Climatic temperature varies with seasonal variation at HA. The present study was undertaken to investigate the effect of ambient temperature on antioxidant profile among sojourners at HA. The study was conducted on sojourners exposed to an altitude of 4,560 m in two different seasons and categorized into two groups (SOJ 1, n = 63, ambient temp. at HA: -6º to +10ºC; SOJ 2, n = 81, ambient temp. at HA: 3º-22ºC). Blood was collected at sea level (SL) and after 4 weeks of HA exposure. Antioxidant enzymes showed significant upregulation in SOJ 2 at HA. In SOJ 1, superoxide dismutase and glutathione peroxidase showed significant upregulation but catalase and glutathione reductase showed significant decrease at HA. Non-enzymatic antioxidants showed significant reduction in SOJ 1 whereas a sustained antioxidant profile was observed in SOJ 2 at HA. Oxidative stress markers showed higher levels in SOJ 1 than SOJ 2 at HA. Differences observed between SOJ 1 and SOJ 2 at HA may be the consequence of different environmental temperatures. Cold stress was higher in SOJ 1 as evidenced from the significantly lower oral temperature in SOJ 1 as compared to SOJ 2. Cold- and hypoxia-induced increase in energy expenditure was significantly high in SOJ 1 than SOJ 2. To conclude, chronic exposure to hypoxia in moderate climatic temperature has a potential preconditioning effect on antioxidant system, but exposure to both cold and hypoxia causes greater oxidative stress due to altered metabolic rate.

  18. Changes in ultrastructure and responses of antioxidant systems of algae (Dunaliella salina) during acclimation to enhanced ultraviolet-B radiation.

    PubMed

    Tian, Jiyuan; Yu, Juan

    2009-12-01

    Because of depletion of the stratospheric ozone layer, levels of solar ultraviolet-B (UV-B) radiation (280-315 nm), which penetrates the water column to an ecologically-significant depth, are increasing. In order to assess changes in ultrastructure and responses of antioxidant systems of algae during acclimation to enhanced ultraviolet-B radiation, Dunaliella salina was treated with higher dose of UV-B radiation (13.2 kJm(-2) d(-1) dose) in this study. As compared to the control panel (8.8 kJm(-2) d(-1)), the treatment D. salina had many changes in ultrastructures: (1) thylakoids became swelled, and some of them penetrated into the pyrenoid; (2) lipid globules accumulated; (3) the amounts of starch grains increased; (4) cristae of mitochondria disintegrated; (5) inclusions in vacuoles reduced; and (6) cisternae of Golgi dictyosomes became loose and swollen. Enhanced UV-B irradiation also induced different responses of the antioxidant systems in D. salina: (1) contents of TBARS (thiobarbituric acid reacting substance) and H(2)O(2) increased significantly (p<0.05); (2) levels of MAAs (mycosporine-like amino acids) increased at the beginning and subsequently decreased, and finally they leveled off at lower values; (3) there were not apparent variations for carotenoid contents, and contents of chlorophyll a presented a trend of initial increase and ultimate decrease; (4) both ascorbate and glutathione contents increased significantly (p<0.05); and (5) for the enzyme activities, POD activities increased remarkably (p<0.05), and SOD activities declined apparently (p<0.05), and CAT activity in D. salina had slight variations (p>0.05). In addition, growth curve displayed that enhanced UV-B radiation prominently inhibited increase of cell concentration when compared with control panel (p<0.05). Our results indicated that enhanced UV-B radiation caused ultrastructural changes of D. salina and induced different responses of antioxidant systems in D. salina. PMID:19818642

  19. Changes in ultrastructure and responses of antioxidant systems of algae (Dunaliella salina) during acclimation to enhanced ultraviolet-B radiation.

    PubMed

    Tian, Jiyuan; Yu, Juan

    2009-12-01

    Because of depletion of the stratospheric ozone layer, levels of solar ultraviolet-B (UV-B) radiation (280-315 nm), which penetrates the water column to an ecologically-significant depth, are increasing. In order to assess changes in ultrastructure and responses of antioxidant systems of algae during acclimation to enhanced ultraviolet-B radiation, Dunaliella salina was treated with higher dose of UV-B radiation (13.2 kJm(-2) d(-1) dose) in this study. As compared to the control panel (8.8 kJm(-2) d(-1)), the treatment D. salina had many changes in ultrastructures: (1) thylakoids became swelled, and some of them penetrated into the pyrenoid; (2) lipid globules accumulated; (3) the amounts of starch grains increased; (4) cristae of mitochondria disintegrated; (5) inclusions in vacuoles reduced; and (6) cisternae of Golgi dictyosomes became loose and swollen. Enhanced UV-B irradiation also induced different responses of the antioxidant systems in D. salina: (1) contents of TBARS (thiobarbituric acid reacting substance) and H(2)O(2) increased significantly (p<0.05); (2) levels of MAAs (mycosporine-like amino acids) increased at the beginning and subsequently decreased, and finally they leveled off at lower values; (3) there were not apparent variations for carotenoid contents, and contents of chlorophyll a presented a trend of initial increase and ultimate decrease; (4) both ascorbate and glutathione contents increased significantly (p<0.05); and (5) for the enzyme activities, POD activities increased remarkably (p<0.05), and SOD activities declined apparently (p<0.05), and CAT activity in D. salina had slight variations (p>0.05). In addition, growth curve displayed that enhanced UV-B radiation prominently inhibited increase of cell concentration when compared with control panel (p<0.05). Our results indicated that enhanced UV-B radiation caused ultrastructural changes of D. salina and induced different responses of antioxidant systems in D. salina.

  20. 33 CFR Appendix C to Part 155 - Training Elements for Oil Spill Response Plans

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... worker health and safety (29 CFR 1910.120). 3. Further Considerations In drafting the training section of... Response Plans C Appendix C to Part 155 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND.... 155, App. C Appendix C to Part 155—Training Elements for Oil Spill Response Plans 1. General...

  1. The toxic effects of ammonia exposure on antioxidant and immune responses in Rockfish, Sebastes schlegelii during thermal stress.

    PubMed

    Kim, Shin-Hu; Kim, Jun-Hwan; Park, Myoung-Ae; Hwang, Seong Don; Kang, Ju-Chan

    2015-11-01

    Rockfish, Sebastes schlegelii (mean weight 14.53 ± 1.14 cm, and mean weight 38.36 ± 3.45 g) were exposed for 4 weeks (2 weeks and 4 weeks) with the different levels of ammonia in the concentrations of 0, 0.1, 0.5, 1.0mg/L at 19 and 24°C. The ammonia exposure induced significant alterations in antioxidant responses. The activities of SOD, CAT, and GST were considerably increased by the ammonia exposure depending on water temperature, whereas the GSH level was notably decreased after 2 and 4 weeks. In the stress indicators, the cortisol and HSP 70 were significantly elevated by the exposure to ammonia depending on water temperature. In innate immune responses, the phagocytosis and lysozyme activity were notably decreased by ammonia exposure depending on water temperature after 2 and 4 weeks. The results suggest that ammonia exposure depending on water temperature can induce the considerable alterations in antioxidant responses, stress, and immune inhibition.

  2. Optimization extraction conditions for improving phenolic content and antioxidant activity in Berberis asiatica fruits using response surface methodology (RSM).

    PubMed

    Belwal, Tarun; Dhyani, Praveen; Bhatt, Indra D; Rawal, Ranbeer Singh; Pande, Veena

    2016-09-15

    This study for the first time designed to optimize the extraction of phenolic compounds and antioxidant potential of Berberis asiatica fruits using response surface methodology (RSM). Solvent selection was done based on the preliminary experiments and a five-factors-three-level, Central Composite Design (CCD). Extraction temperature (X1), sample to solvent ratio (X3) and solvent concentration (X5) significantly affect response variables. The quadratic model well fitted for all the responses. Under optimal extraction conditions, the dried fruit sample mixed with 80% methanol having 3.0 pH in a ratio of 1:50 and the mixture was heated at 80 °C for 30 min; the measured parameters was found in accordance with the predicted values. High Performance Liquid Chromatography (HPLC) analysis at optimized condition reveals 6 phenolic compounds. The results suggest that optimization of the extraction conditions is critical for accurate quantification of phenolics and antioxidants in Berberis asiatica fruits, which may further be utilized for industrial extraction procedure.

  3. Photooxidation and antioxidant responses in the earthworm Amynthas gracilis exposed to environmental levels of ultraviolet B radiation.

    PubMed

    Chuang, Shu-Chun; Chen, Jiun-Hong

    2013-03-01

    Ultraviolet (UV) radiation leads to photooxidation in various organisms. Our previous study demonstrated that ultraviolet B (UV-B) radiation is lethal for particular species of earthworms, but the mechanisms responsible for the lethality are unclear. In our current study, we investigated that ultraviolet light causes photooxidative damage and reduces antioxidant responses in the earthworm Amynthas gracilis. Intact earthworms and skin/muscle tissue extracts were exposed to UV-B radiation for in vivo and in vitro studies. Both in vitro and in vivo results showed that the products of photooxidative damage, MDA and H(2)O(2), increased after UV-B exposure. Glutathione peroxidase (GPx) and catalase were inhibited immediately after exposure to high doses (3000J/m(2)) of UV-B radiation in vivo. Catalase activity was increased following a low UV-B dose (500J/m(2)) in vivo, but decreased in response to all dosage levels in vitro. These data indicate that a relationship exists between UV-B induced damage and photooxidation and also that catalase and GPx act as important antioxidants to prevent photooxidation. According to these data, A. gracilis exhibits high sensitivity to environmental levels of UV-B. Therefore, A. gracilis represents a sensitive and cost-effective model organism for investigations of UV-radiation damage and environmental UV stress.

  4. Vibration response mechanism of faulty outer race rolling element bearings for quantitative analysis

    NASA Astrophysics Data System (ADS)

    Cui, Lingli; Zhang, Yu; Zhang, Feibin; Zhang, Jianyu; Lee, Seungchul

    2016-03-01

    For the quantitative fault diagnosis of rolling element bearings, a nonlinear vibration model for fault severity assessment of rolling element bearings is established in this study. The outer race defect size parameter is introduced into the dynamic model, and vibration response signals of rolling element bearings under different fault sizes are simulated. The signals are analyzed quantitatively to observe the relationship between vibration responses and fault sizes. The impact points when the ball rolls onto and away from the defect are identified from the vibration response signals. Next, the impact characteristic that reflects the fault severity in rolling element bearings is obtained from the time interval between two impact points. When the width of the bearing fault is small, the signals are presented as clear single impact. The signals gradually become double impacts with increasing size of defects. The vibration signals of a rolling element bearings test rig are measured for different outer race fault sizes. The experimental results agree well with the results from simulations. These results are useful for understanding the vibration response mechanism of rolling element bearings under various degrees of fault severity.

  5. Therapeutic targeting of GSK3β enhances the Nrf2 antioxidant response and confers hepatic cytoprotection in hepatitis C

    PubMed Central

    Jiang, Yongfang; Bao, Hui; Ge, Yan; Tang, Wei; Cheng, Du; Luo, Kaizhong; Gong, Guozhong; Gong, Rujun

    2014-01-01

    Objective Impaired adaptive response to oxidative injuries is a fundamental mechanism central to the pathogenesis of chronic hepatitis C (CHC). Glycogen synthase kinase (GSK) 3β is an indispensable regulator of the oxidative stress response. However, the exact role of GSK3β in CHC is uncertain and was examined. Design GSK3β and Nrf2 signaling pathways were examined in JFH1 hepatitis C virus (HCV) infected Huh 7.5.1 hepatocytes and also in liver biopsy specimens from CHC patients. Results HCV infection elicited prominent Nrf2 antioxidant response in hepatocytes, marked by elevated expression of the Nrf2 dependent molecule heme oxygenase-1 and subsequent protection from apoptotic cell death. Inhibitory phosphorylation of GSK3β seems to be essential and sufficient for HCV induced Nrf2 response. Mechanistically, GSK3β physically associated and interacted with Nrf2 in hepatocytes. In silico analysis revealed that Nrf2 encompasses multiple GSK3β phosphorylation consensus motifs, denoting Nrf2 as a cognate substrate of GSK3β. In the presence of TGFβ1, the HCV induced GSK3β phosphorylation was blunted via a protein phosphatase 1-dependent mechanism and the cytoprotective Nrf2 response drastically impaired. Lithium, a selective inhibitor of GSK3β, counteracted the effects of TGFβ1. In liver biopsy specimens from CHC patients, the expression of phosphorylated GSK3β positively correlated with Nrf2 expression and was inversely associated with the degree of liver injury. Moreover, CHC patients who received long-term lithium carbonate therapy primarily for concomitant psychiatric disorders exhibited much less liver injury, associated with enhanced hepatic expression of Nrf2. Conclusions Inhibition of GSK3β exerts hepatoprotection in CHC possibly through its direct regulation of Nrf2 antioxidant response. PMID:24811996

  6. Antioxidative responses of Ocimum basilicum to sodium chloride or sodium sulphate salinization.

    PubMed

    Tarchoune, I; Sgherri, C; Izzo, R; Lachaal, M; Ouerghi, Z; Navari-Izzo, F

    2010-09-01

    Soils and ground water in nature are dominated by chloride and sulphate salts. There have been several studies concerning NaCl salinity, however, little is known about the Na(2)SO(4) one. The effects on antioxidative activities of chloride or sodium sulphate in terms of the same Na(+) equivalents (25 mM Na(2)SO(4) and 50 mM NaCl) were studied on 30 day-old plants of Ocimum basilicum L., variety Genovese subjected to 15 and 30 days of treatment. Growth, thiobarbituric acid reactive substances (TBARS), relative ion leakage ratio (RLR), hydrogen peroxide (H(2)O(2)), ascorbate and glutathione contents as well as the activities of ascorbate peroxidase (APX, EC 1.11.1.11); glutathione reductase (GR, EC 1.6.4.2) and peroxidases (POD, EC 1.11.1.7) were determined. In leaves, growth was more depressed by 25 mM Na(2)SO(4) than 50 mM NaCl. The higher sensitivity of basil to Na(2)SO(4) was associated with an enhanced accumulation of H(2)O(2), an inhibition of APX, GR and POD activities (with the exception of POD under the 30-day-treatment) and a lower regeneration of reduced ascorbate (AsA) and reduced glutathione (GSH). However, the changes in the antioxidant metabolism were enough to limit oxidative damage, explaining the fact that RLR and TBARS levels were unchanged under both Na(2)SO(4) and NaCl treatment. Moreover, for both salts the 30-day-treatment reduced H(2)O(2) accumulation, unchanged RLR and TBARS levels, and enhanced the levels of antioxidants and antioxidative enzymes, thus achieving an adaptation mechanism against reactive oxygen species.

  7. Implications of chronic daily anti-oxidant administration on the inflammatory response to intracortical microelectrodes

    NASA Astrophysics Data System (ADS)

    Potter-Baker, Kelsey A.; Stewart, Wade G.; Tomaszewski, William H.; Wong, Chun T.; Meador, William D.; Ziats, Nicholas P.; Capadona, Jeffrey R.

    2015-08-01

    Objective. Oxidative stress events have been implicated to occur and facilitate multiple failure modes of intracortical microelectrodes. The goal of the present study was to evaluate the ability of a sustained concentration of an anti-oxidant and to reduce oxidative stress-mediated neurodegeneration for the application of intracortical microelectrodes. Approach. Non-functional microelectrodes were implanted into the cortex of male Sprague Dawley rats for up to sixteen weeks. Half of the animals received a daily intraperitoneal injection of the natural anti-oxidant resveratrol, at 30 mg kg-1. The study was designed to investigate the biodistribution of the resveratrol, and the effects on neuroinflammation/neuroprotection following device implantation. Main results. Daily maintenance of a sustained range of resveratrol throughout the implantation period resulted in fewer degenerating neurons in comparison to control animals at both two and sixteen weeks post implantation. Initial and chronic improvements in neuronal viability in resveratrol-dosed animals were correlated with significant reductions in local superoxide anion accumulation around the implanted device at two weeks after implantation. Controls, receiving only saline injections, were also found to have reduced amounts of accumulated superoxide anion locally and less neurodegeneration than controls at sixteen weeks post-implantation. Despite observed benefits, thread-like adhesions were found between the liver and diaphragm in resveratrol-dosed animals. Significance. Overall, our chronic daily anti-oxidant dosing scheme resulted in improvements in neuronal viability surrounding implanted microelectrodes, which could result in improved device performance. However, due to the discovery of thread-like adhesions, further work is still required to optimize a chronic anti-oxidant dosing regime for the application of intracortical microelectrodes.

  8. Implications of Chronic Daily Anti-Oxidant Administration on the Inflammatory Response to Intracortical Microelectrodes

    PubMed Central

    Potter-Baker, Kelsey A.; Stewart, Wade G.; Tomaszewski, William H.; Wong, Chun T.; Meador, William D.; Ziats, Nicholas P.; Capadona, Jeffrey R.

    2015-01-01

    Objective Oxidative stress events have been implicated to occur and facilitate multiple failure modes of intracortical microelectrodes. The goal of the present study was to evaluate the ability of a sustained concentration of an anti-oxidant and to reduce oxidative stress-mediated neurodegeneration for the application of intracortical microelectrodes. Approach Non-functional microelectrodes were implanted into the cortex of male Sprague Dawley rats for up to sixteen weeks. Half of the animals received a daily intraperitoneal injection of the natural anti-oxidant resveratrol, at 30 mg/kg. The study was designed to investigate the biodistribution of the resveratrol, and the effects on neuroinflammation/neuroprotection following device implantation. Main Results Daily maintenance of a sustained range of resveratrol throughout the implantation period resulted in fewer degenerating neurons in comparison to control animals at both two and sixteen weeks post implantation. Initial and chronic improvements in neuronal viability in resveratrol-dosed animals were correlated with significant reductions in local superoxide anion accumulation around the implanted device at two weeks after implantation. Controls, receiving only saline injections, were also found to have reduced amounts of accumulated superoxide anion locally and less neurodegeneration than controls at sixteen weeks post-implantation. Despite observed benefits, thread-like adhesions were found between the liver and diaphragm in resveratrol-dosed animals. Significance Overall, our chronic daily anti-oxidant dosing scheme resulted in improvements in neuronal viability surrounding implanted microelectrodes, which could result in improved device performance. However, due to the discovery of thread-like adhesions, further work is still required to optimize a chronic anti-oxidant dosing regime for the application of intracortical microelectrodes. PMID:26015427

  9. Nicotine mediates expression of genes related to antioxidant capacity and oxidative stress response in HIV-1 transgenic rat brain.

    PubMed

    Song, Guohua; Nesil, Tanseli; Cao, Junran; Yang, Zhongli; Chang, Sulie L; Li, Ming D

    2016-02-01

    Oxidative stress plays an important role in the progression of HIV-1 infection. Nicotine can either protect neurons from neurodegeneration or induce oxidative stress, depending on its dose and degree of oxidative stress impairment. However, the relationship between nicotine and oxidative stress in the HIV-1-infected individuals remains largely unknown. The purpose of this study was to determine the effect of nicotine on expression of genes related to the glutathione (GSH)-centered antioxidant system and oxidative stress in the nucleus accumbens (NAc) and ventral tegmental area (VTA) of HIV-1 transgenic (HIV-1Tg) and F344 control rats. Adult HIV-1Tg and F344 rats received nicotine (0.4 mg/kg, base, s.c.) or saline injections once per day for 27 days. At the end of treatment, various brain regions including the NAc and VTA were collected from each rat. Following total RNA extraction and complementary DNA (cDNA) synthesis of each sample, quantitative reverse transcription PCR (RT-PCR) analysis was performed for 43 oxidative-stress-related genes. Compared with F344 control rats, HIV-1Tg rats showed a significant downregulation of genes involved in ATPase and cyctochrome oxidase at the messenger RNA (mRNA) level in both regions. Further, we found a significant downregulation of Gstm5 in the NAc and upregulation of Cox1, Cox3, and Gsta6 in the VTA of HIV-1Tg rats. HIV-1Tg rats showed brain-region-specific responses to chronic nicotine treatment. This response resulted in a change in the expression of genes involved in antioxidant mechanisms including the downregulation of genes such as Atp5h, Calml1, Gpx7, Gstm5, Gsr, and Gsta6 and upregulation of Sod1 in the NAc, as well as downregulation of genes like Cox5a, Gpx4, Gpx6, Gpx7, Gstm5, and Sod1 in the VTA of HIV-1Tg rats. Together, we conclude that chronic nicotine treatment has a dual effect on the antioxidant defense system and oxidative-stress-induced apoptosis signaling in HIV-1Tg rats. These findings suggest that

  10. Isolation and identification of compounds responsible for antioxidant capacity of Euryale ferox seeds.

    PubMed

    Song, Chang-Wei; Wang, Shu-Mei; Zhou, Li-Li; Hou, Fan-Fan; Wang, Kai-Jin; Han, Quan-Bin; Li, Ning; Cheng, Yong-Xian

    2011-02-23

    Euryale ferox seed is consumed medicinally or for food in China. The present study revealed it to contain significant antioxidant activity, which may be associated with its medical applications as a proteinuria inhibitor of diabetic nephropathy. This study resulted in the identification of 3 new sesquineolignans, named euryalins A-C (1-3), and 16 known compounds, which were all first isolated from this plant apart from 5,7,4-trihydroxy-flavanone. The antioxidant potential of the partial isolates was evaluated using the DPPH radical scavenging assay and mesangial cellular assay. Compounds 2, rel-(2α,3β)-7-O-methylcedrusin (4), syringylglycerol-8-O-4-(sinapyl alcohol) ether (5), and (+)-syringaresinol (7) were found to be most active on DPPH assay, whereas compounds 2, 4, 7, (1R,2R,5R,6S)-2-(3,4-dimethoxyphenyl)-6-(3,4-dihydroxyphenyl)-3,7-dioxabicyclo[3.3.0]octane, and buddlenol E could significantly inhibit high glucose-stimulated reactive oxygen species production in mesangial cells. The results suggested that E. ferox seed could be considered as an excellent source of natural antioxidants and is useful in the prevention of diabetic nephropathy.

  11. Divergences in hormonal and enzymatic antioxidant responses of two Chicory ecotypes to salt stress.

    PubMed

    Ghanaatiyan, Kimiya; Sadeghi, Hossein

    2015-06-15

    To evaluate the effect of salt stress on seed germination, early growth, antioxidant enzymes activity and ABA content of chicory ecotypes (Cichorium intybus) a factorial experiment was conducted at College of Agriculture, Shiraz University in 2014 based on completely randomized design with four replications. The treatments comprised five salinity levels (tapwater, 3, 6, 9, 12 dS m(-1)) of sodium chloride on Shirazi-black and white chicory ecotypes. The results showed that germination characteristics and primary seedling growth were decreased in both ecotypes with increasing in salinity severity. The effects of salinity on radicle and plumule length as well as seedling weight were the same as its effects on seed germination. The effect of salt stress on antioxidant enzymes activity (especially catalase) and ABA content were significant which they were enhanced with increasing salinity level; Black ecotype performs better than the white one under high salinity, as indicated by a lower decreasing in germination characteristics and primary growth and higher antioxidant enzymes activity as well as ABA content. These facts should be taken into consideration in the economic cultivation of this valuable horticultural and medicinal plant and this data would be useful for the crop breeding projects. PMID:26075934

  12. Response of antioxidant defences to Zn stress in three duckweed species.

    PubMed

    Uruç Parlak, Kadiriye; Demirezen Yilmaz, Dilek

    2012-11-01

    In the plants, Lemna gibba, Lemna minor and Spirodela polyrrhiza L., the effect of different concentrations of zinc (0.01, 0.05, 0.1, 0.5 and 1.5mgL(-1) Zn) applied for four day was assessed by measuring changes in the chlorophyll, protein, malondialdehyde (MDA), catalase (CAT), superoxide dismutase (SOD), ascorbate peroxidase (APX) and guiacolperoxidase (GPX) activity of the plants. According to results, Zn contents in plants increased with increasing Zn supply levels. The level of photosynthetic pigments and soluble proteins reduced only upon exposure to high Zn concentrations. At the same time, the level of malondialdehyde (MDA) increased with increasing Zn concentration. These results suggested an alleviation of stress that was possibly the result of antioxidants such as catalase (CAT), superoxide dismutase (SOD), ascorbate peroxidase (APX) as well as guaiacol peroxidise (GPOX), which increased linearly with increasing Zn levels. Cellular antioxidant levels showed an increase suggesting a defensive mechanism to preserve against oxidative stress given rise to by Zn. Besides, the proline amount in L. gibba, L. minor and S. polyrrhiza increased with increasing zinc levels. These conclusions proposed that L. gibba, L. minor and S. polyrrhiza are supplied with an efficient antioxidant mechanism against Zn-induced oxidative stress which saves the plant's photosynthetic machinery from damage. It is concluded that higher zinc levels cause oxidative stress in L. gibba, L. minor and S. polyrrhiza cells and may reason membrane damage through production of ROS and interferes with chlorophyll metabolism. PMID:23009815

  13. Isolation and identification of compounds responsible for antioxidant capacity of Euryale ferox seeds.

    PubMed

    Song, Chang-Wei; Wang, Shu-Mei; Zhou, Li-Li; Hou, Fan-Fan; Wang, Kai-Jin; Han, Quan-Bin; Li, Ning; Cheng, Yong-Xian

    2011-02-23

    Euryale ferox seed is consumed medicinally or for food in China. The present study revealed it to contain significant antioxidant activity, which may be associated with its medical applications as a proteinuria inhibitor of diabetic nephropathy. This study resulted in the identification of 3 new sesquineolignans, named euryalins A-C (1-3), and 16 known compounds, which were all first isolated from this plant apart from 5,7,4-trihydroxy-flavanone. The antioxidant potential of the partial isolates was evaluated using the DPPH radical scavenging assay and mesangial cellular assay. Compounds 2, rel-(2α,3β)-7-O-methylcedrusin (4), syringylglycerol-8-O-4-(sinapyl alcohol) ether (5), and (+)-syringaresinol (7) were found to be most active on DPPH assay, whereas compounds 2, 4, 7, (1R,2R,5R,6S)-2-(3,4-dimethoxyphenyl)-6-(3,4-dihydroxyphenyl)-3,7-dioxabicyclo[3.3.0]octane, and buddlenol E could significantly inhibit high glucose-stimulated reactive oxygen species production in mesangial cells. The results suggested that E. ferox seed could be considered as an excellent source of natural antioxidants and is useful in the prevention of diabetic nephropathy. PMID:21280632

  14. Characterization of the nutraceutical quality and antioxidant activity in bell pepper in response to grafting.

    PubMed

    Chávez-Mendoza, Celia; Sánchez, Esteban; Carvajal-Millán, Elizabeth; Muñoz-Márquez, Ezequiel; Guevara-Aguilar, Alexandro

    2013-12-16

    The grafting of fruits and vegetables influences fruit quality. The aim of the present work was to assess the effect of the rootstock and the scion on the antioxidant activity and the content in vitamin C, total phenols, lycopene and β-carotene of bell pepper. The cultivars Fascinato and Jeanette were used as scion and Terrano was used as rootstock. Four harvests in the production cycle of the vegetable were analyzed in a cultivation system under shading nets. The results indicate statistical differences in the content of these bioactive compounds between the varieties, between grafting and not grafting and between sampling dates (p ≤ 0.05). The vitamin C content, β-carotene, and antioxidant capacity proved significantly higher in Fascinato than in Janette. On average, grafting increased β-carotene and vitamin C concentrations and improved the antioxidant capacity, but had no influence on the total phenol or lycopene contents. It is concluded that grafting to the rootstock Terrano improves the nutritional quality of the fruit produced in both varieties of bell pepper studied.

  15. Response of antioxidant defences to Zn stress in three duckweed species.

    PubMed

    Uruç Parlak, Kadiriye; Demirezen Yilmaz, Dilek

    2012-11-01

    In the plants, Lemna gibba, Lemna minor and Spirodela polyrrhiza L., the effect of different concentrations of zinc (0.01, 0.05, 0.1, 0.5 and 1.5mgL(-1) Zn) applied for four day was assessed by measuring changes in the chlorophyll, protein, malondialdehyde (MDA), catalase (CAT), superoxide dismutase (SOD), ascorbate peroxidase (APX) and guiacolperoxidase (GPX) activity of the plants. According to results, Zn contents in plants increased with increasing Zn supply levels. The level of photosynthetic pigments and soluble proteins reduced only upon exposure to high Zn concentrations. At the same time, the level of malondialdehyde (MDA) increased with increasing Zn concentration. These results suggested an alleviation of stress that was possibly the result of antioxidants such as catalase (CAT), superoxide dismutase (SOD), ascorbate peroxidase (APX) as well as guaiacol peroxidise (GPOX), which increased linearly with increasing Zn levels. Cellular antioxidant levels showed an increase suggesting a defensive mechanism to preserve against oxidative stress given rise to by Zn. Besides, the proline amount in L. gibba, L. minor and S. polyrrhiza increased with increasing zinc levels. These conclusions proposed that L. gibba, L. minor and S. polyrrhiza are supplied with an efficient antioxidant mechanism against Zn-induced oxidative stress which saves the plant's photosynthetic machinery from damage. It is concluded that higher zinc levels cause oxidative stress in L. gibba, L. minor and S. polyrrhiza cells and may reason membrane damage through production of ROS and interferes with chlorophyll metabolism.

  16. Characterization of the nutraceutical quality and antioxidant activity in bell pepper in response to grafting.

    PubMed

    Chávez-Mendoza, Celia; Sánchez, Esteban; Carvajal-Millán, Elizabeth; Muñoz-Márquez, Ezequiel; Guevara-Aguilar, Alexandro

    2013-01-01

    The grafting of fruits and vegetables influences fruit quality. The aim of the present work was to assess the effect of the rootstock and the scion on the antioxidant activity and the content in vitamin C, total phenols, lycopene and β-carotene of bell pepper. The cultivars Fascinato and Jeanette were used as scion and Terrano was used as rootstock. Four harvests in the production cycle of the vegetable were analyzed in a cultivation system under shading nets. The results indicate statistical differences in the content of these bioactive compounds between the varieties, between grafting and not grafting and between sampling dates (p ≤ 0.05). The vitamin C content, β-carotene, and antioxidant capacity proved significantly higher in Fascinato than in Janette. On average, grafting increased β-carotene and vitamin C concentrations and improved the antioxidant capacity, but had no influence on the total phenol or lycopene contents. It is concluded that grafting to the rootstock Terrano improves the nutritional quality of the fruit produced in both varieties of bell pepper studied. PMID:24352022

  17. Antioxidant status, metabolic profile and immune response of lambs supplemented with tannin rich Ficus infectoria leaf meal.

    PubMed

    Dey, Avijit; Dutta, Narayan; Pattanaik, Ashok Kumar; Sharma, Kusumakar

    2015-02-01

    To study the effect of supplementation of tanniferous tree leaves Ficus infectoria on antioxidant status and immune response, twenty four lambs were randomly divided into four groups of six each in a completely randomized design and fed either a conventional supplement (CON) or experimental supplements (FILM-I, FILM-II and FILM-III) containing 1.0, 1.5 and 2.0% condensed tannins (CT), respectively by replacement of wheat bran of supplement CON with Ficus infectoria leaf meal (FILM). Blood biochemical profile was monitored in all lambs at 0, 45, 90, 135, 180 days of feeding. Although haemato-biochemical parameters remained similar, there was significant (p < 0.05) improvement in catalase activity, total thiol and protein thiol groups with reduction in lipid peroxidation (LPO) in lambs fed FILM diet irrespective of levels. However, intracellular status of reduced glutathione, and superoxide dismutase activity was improved (p < 0.05) only in FILM-II and FILM-III supplemented lambs. The cell-mediated immune response was significantly (p < 0.05) improved in all the lambs fed FILM supplemented diets. Improved antioxidant status and immunity in FILM supplemented lambs increased voluntary feed intake irrespective of level. However, the average daily gain for a period of 180 d showed a significant (p < 0.05) increase by the supplementation of FILM-II diet containing 1.5% CT. The present study reveals that the supplementation of Ficus infectoria leaf meal up to 21.2% in the concentrate mixture could improve the antioxidant status and immunity in lambs. However, as feed efficiency was reduced at higher levels due to presence of CT, 15.9% supplementation containing 1.5% condensed tannins in concentrate mixture is suggested to improve the health and production performance of lambs.

  18. Nrf2-mediated transcriptional induction of antioxidant response in mouse embryos exposed to ethanol in vivo: implications for the prevention of fetal alcohol spectrum disorders.

    PubMed

    Dong, Jian; Sulik, Kathleen K; Chen, Shao-Yu

    2008-12-01

    Nuclear factor erythroid 2-related factor 2 (Nrf2) is a transcription factor that is important in protection against oxidative stress. This study was designed to determine the role of Nrf2 signaling in transcriptional activation of detoxifying and antioxidant genes in an in vivo mouse fetal alcohol syndrome model. Maternal ethanol treatment was found to increase both Nrf2 protein levels and Nrf2-ARE binding in mouse embryos. It also resulted in a moderate increase in the mRNA expression of Nrf2 downstream target detoxifying and antioxidant genes as well as an increase in the expression of antioxidant proteins. Pretreatment with the Nrf2 inducer, 3H-1,2 dithiole-3-thione (D3T), significantly increased Nrf2 protein levels and Nrf2-ARE binding, and strongly induced the mRNA expression of Nrf2 downstream target genes. It also increased the expression of antioxidant proteins and the activities of the antioxidant enzymes. Additionally, D3T pretreatment resulted in a significant decrease in ethanol-induced reactive oxygen species generation and apoptosis in mouse embryos. These results demonstrate that Nrf2 signaling is involved in the induction of antioxidant response in ethanol-exposed embryos. In addition, the potency of D3T in inducing antioxidants as well as in diminishing ethanol-induced apoptosis suggests that further exploration of the antiteratogenic effect of this compound will be fruitful.

  19. Structural basis of VDR–DNA interactions on direct repeat response elements

    PubMed Central

    Shaffer, Paul L.; Gewirth, Daniel T.

    2002-01-01

    The vitamin D receptor (VDR) forms homo- or heterodimers on response elements composed of two hexameric half-sites separated by 3 bp of spacer DNA. We describe here the crystal structures at 2.7–2.8 Å resolution of the VDR DNA-binding region (DBD) in complex with response elements from three different promoters: osteopontin (SPP), canonical DR3 and osteocalcin (OC). These structures reveal the chemical basis for the increased affinity of VDR for the SPP response element, and for the poor stability of the VDR–OC complex, relative to the canonical DR3 response element. The homodimeric protein–protein interface is stabilized by van der Waals interactions and is predominantly non-polar. An extensive α-helix at the C-terminal end of the VDR DBD resembles that found in the thyroid hormone receptor (TR), and suggests a mechanism by which VDR and TR discriminate among response elements. Selective structure-based mutations in the asymmetric homodimeric interface result in a VDR DBD protein that is defective in homodimerization but now forms heterodimers with the 9-cis retinoic acid receptor (RXR) DBD. PMID:11980721

  20. Conserved enhancer and silencer elements responsible for differential Adh transcription in Drosophila cell lines.

    PubMed Central

    Ayer, S; Benyajati, C

    1990-01-01

    The distal promoter of Adh is differentially expressed in Drosophila tissue culture cell lines. After transfection with an exogenous Adh gene, there was a specific increase in distal alcohol dehydrogenase (ADH) transcripts in ADH-expressing (ADH+) cells above the levels observed in transfected ADH-nonexpressing (ADH-) cells. We used deletion mutations and a comparative transient-expression assay to identify the cis-acting elements responsible for enhanced Adh distal transcription in ADH+ cells. DNA sequences controlling high levels of distal transcription were localized to a 15-base-pair (bp) region nearly 500 bp upstream of the distal RNA start site. In addition, a 61-bp negative cis-acting element was found upstream from and adjacent to the enhancer. When this silencer element was deleted, distal transcription increased only in the ADH+ cell line. These distant upstream elements must interact with the promoter elements, the Adf-1-binding site and the TATA box, as they only influenced transcription when at least one of these two positive distal promoter elements was present. Internal deletions targeted to the Adf-1-binding site or the TATA box reduced transcription in both cell types but did not affect the transcription initiation site. Distal transcription in transfected ADH- cells appears to be controlled primarily through these promoter elements and does not involve the upstream regulatory elements. Evolutionary conservation in distantly related Drosophila species suggests the importance of these upstream elements in correct developmental and tissue-specific expression of ADH. Images PMID:1694013

  1. A High Antioxidant Spice Blend Attenuates Postprandial Insulin and Triglyceride Responses and Increases Some Plasma Measures of Antioxidant Activity in Healthy, Overweight Men123

    PubMed Central

    Skulas-Ray, Ann C.; Kris-Etherton, Penny M.; Teeter, Danette L.; Chen, C-Y. Oliver; Vanden Heuvel, John P.; West, Sheila G.

    2011-01-01

    There is much interest in the potential of dietary antioxidants to attenuate in vivo oxidative stress, but little characterization of the time course of plasma effects exists. Culinary spices have demonstrated potent in vitro antioxidant properties. The objective of this study was to examine whether adding 14 g of a high antioxidant spice blend to a 5060-kJ (1200 kcal) meal exerted significant postprandial effects on markers of plasma antioxidant status and metabolism. Healthy overweight men (n = 6) consumed a control and spiced meal in a randomized crossover design with 1 wk between testing sessions. Blood was sampled prior to the meal and at 30-min intervals for 3.5 h (total of 8 samples). Mixed linear models demonstrated a treatment × time interaction (P < 0.05) for insulin and TG, corresponding with 21 and 31% reductions in postprandial levels with the spiced meal, respectively. Adding spices to the meal significantly increased the ferric reducing antioxidant power, such that postprandial increases following the spiced meal were 2-fold greater than after the control meal (P = 0.009). The hydrophilic oxygen radical absorbance capacity (ORAC) of plasma also was increased by spices (P = 0.02). There were no treatment differences in glucose, total thiols, lipophilic ORAC, or total ORAC. The incorporation of spices into the diet may help normalize postprandial insulin and TG and enhance antioxidant defenses. PMID:21697300

  2. Response and adaptation of photosynthesis, respiration, and antioxidant systems to elevated CO2 with environmental stress in plants

    PubMed Central

    Xu, Zhenzhu; Jiang, Yanling; Zhou, Guangsheng

    2015-01-01

    It is well known that plant photosynthesis and respiration are two fundamental and crucial physiological processes, while the critical role of the antioxidant system in response to abiotic factors is still a focus point for investigating physiological stress. Although one key metabolic process and its response to climatic change have already been reported and reviewed, an integrative review, including several biological processes at multiple scales, has not been well reported. The current review will present a synthesis focusing on the underlying mechanisms in the responses to elevated CO2 at multiple scales, including molecular, cellular, biochemical, physiological, and individual aspects, particularly, for these biological processes under elevated CO2 with other key abiotic stresses, such as heat, drought, and ozone pollution, as well as nitrogen limitation. The present comprehensive review may add timely and substantial information about the topic in recent studies, while it presents what has been well established in previous reviews. First, an outline of the critical biological processes, and an overview of their roles in environmental regulation, is presented. Second, the research advances with regard to the individual subtopics are reviewed, including the response and adaptation of the photosynthetic capacity, respiration, and antioxidant system to CO2 enrichment alone, and its combination with other climatic change factors. Finally, the potential applications for plant responses at various levels to climate change are discussed. The above issue is currently of crucial concern worldwide, and this review may help in a better understanding of how plants deal with elevated CO2 using other mainstream abiotic factors, including molecular, cellular, biochemical, physiological, and whole individual processes, and the better management of the ecological environment, climate change, and sustainable development. PMID:26442017

  3. Response and adaptation of photosynthesis, respiration, and antioxidant systems to elevated CO2 with environmental stress in plants.

    PubMed

    Xu, Zhenzhu; Jiang, Yanling; Zhou, Guangsheng

    2015-01-01

    It is well known that plant photosynthesis and respiration are two fundamental and crucial physiological processes, while the critical role of the antioxidant system in response to abiotic factors is still a focus point for investigating physiological stress. Although one key metabolic process and its response to climatic change have already been reported and reviewed, an integrative review, including several biological processes at multiple scales, has not been well reported. The current review will present a synthesis focusing on the underlying mechanisms in the responses to elevated CO2 at multiple scales, including molecular, cellular, biochemical, physiological, and individual aspects, particularly, for these biological processes under elevated CO2 with other key abiotic stresses, such as heat, drought, and ozone pollution, as well as nitrogen limitation. The present comprehensive review may add timely and substantial information about the topic in recent studies, while it presents what has been well established in previous reviews. First, an outline of the critical biological processes, and an overview of their roles in environmental regulation, is presented. Second, the research advances with regard to the individual subtopics are reviewed, including the response and adaptation of the photosynthetic capacity, respiration, and antioxidant system to CO2 enrichment alone, and its combination with other climatic change factors. Finally, the potential applications for plant responses at various levels to climate change are discussed. The above issue is currently of crucial concern worldwide, and this review may help in a better understanding of how plants deal with elevated CO2 using other mainstream abiotic factors, including molecular, cellular, biochemical, physiological, and whole individual processes, and the better management of the ecological environment, climate change, and sustainable development. PMID:26442017

  4. Analysis of the antioxidant response of Nicotiana benthamiana to infection with two strains of Pepper mild mottle virus

    PubMed Central

    Hakmaoui, A.; Pérez-Bueno, M. L.; Barón, M.

    2012-01-01

    The present study was carried out to investigate the role of reactive oxygen species (ROS) metabolism in symptom development and pathogenesis in Nicotiana benthamiana plants upon infection with two strains of Pepper mild mottle virus, the Italian (PMMoV-I) and the Spanish (PMMoV-S) strains. In this host, it has been shown that PMMoV-I is less virulent and plants show the capability to recover 21 d after inoculation. Analyses of oxidative stress biomarkers, ROS-scavenging enzyme activities, and antioxidant compounds were conducted in plants at different post-infection times. Only PMMoV-I stimulated a defence response through: (i) up-regulation of different superoxide dismutase isozymes; (ii) maintenance of adequate levels of three peroxiredoxins (2-Cys Prx, Prx IIC, and Prx IIF); and (iii) adjustments in the glutathione pool to maintain the total glutathione content. Moreover, there was an increase in the level of oxidized glutathione and ascorbate in the recovery phase of PMMoV-I-infected plants. The antioxidant response and the extent of oxidative stress in N. benthamiana plants correlates to: (i) the severity of the symptoms elicited by either strain of PMMoV; and (ii) the high capacity of PMMoV-I-infected plants for symptom recovery and delayed senescence, compared with PMMoV-S-infected plants. PMID:22915745

  5. The cinnamon-derived dietary factor cinnamic aldehyde activates the Nrf2-dependent antioxidant response in human epithelial colon cells.

    PubMed

    Wondrak, Georg Thomas; Villeneuve, Nicole F; Lamore, Sarah D; Bause, Alexandra S; Jiang, Tao; Zhang, Donna D

    2010-05-07

    Colorectal cancer (CRC) is a major cause of tumor-related morbidity and mortality worldwide. Recent research suggests that pharmacological intervention using dietary factors that activate the redox sensitive Nrf2/Keap1-ARE signaling pathway may represent a promising strategy for chemoprevention of human cancer including CRC. In our search for dietary Nrf2 activators with potential chemopreventive activity targeting CRC, we have focused our studies on trans-cinnamic aldehyde (cinnamaldeyde, CA), the key flavor compound in cinnamon essential oil. Here we demonstrate that CA and an ethanolic extract (CE) prepared from Cinnamomum cassia bark, standardized for CA content by GC-MS analysis, display equipotent activity as inducers of Nrf2 transcriptional activity. In human colon cancer cells (HCT116, HT29) and non-immortalized primary fetal colon cells (FHC), CA- and CE-treatment upregulated cellular protein levels of Nrf2 and established Nrf2 targets involved in the antioxidant response including heme oxygenase 1 (HO-1) and gamma-glutamyl-cysteine synthetase (gamma-GCS, catalytic subunit). CA- and CE-pretreatment strongly upregulated cellular glutathione levels and protected HCT116 cells against hydrogen peroxide-induced genotoxicity and arsenic-induced oxidative insult. Taken together our data demonstrate that the cinnamon-derived food factor CA is a potent activator of the Nrf2-orchestrated antioxidant response in cultured human epithelial colon cells. CA may therefore represent an underappreciated chemopreventive dietary factor targeting colorectal carcinogenesis.

  6. Hepatic and Nephric NRF2 Pathway Up-Regulation, an Early Antioxidant Response, in Acute Arsenic-Exposed Mice

    PubMed Central

    Li, Jinlong; Duan, Xiaoxu; Dong, Dandan; Zhang, Yang; Li, Wei; Zhao, Lu; Nie, Huifang; Sun, Guifan; Li, Bing

    2015-01-01

    Inorganic arsenic (iAs), a proven human carcinogen, damages biological systems through multiple mechanisms, one of them being reactive oxygen species (ROS) production. NRF2 is a redox-sensitive transcription factor that positively regulates the genes of encoding antioxidant and detoxification enzymes to neutralize ROS. Although NRF2 pathway activation by iAs has been reported in various cell types, however, the experimental data in vivo are very limited and not fully elucidated in humans. The present investigation aimed to explore the hepatic and nephric NRF2 pathway upregulation in acute arsenic-exposed mice in vivo. Our results showed 10 mg/kg NaAsO2 elevated the NRF2 protein and increased the transcription of Nrf2 mRNA, as well as up-regulated NRF2 downstream targets HO-1, GST and GCLC time- and dose-dependently both in the liver and kidney. Acute NaAsO2 exposure also resulted in obvious imbalance of oxidative redox status represented by the increase of GSH and MDA, and the decrease of T-AOC. The present investigation reveals that hepatic and nephric NRF2 pathway expression is an early antioxidant defensive response upon iAs exposure. A better knowledge about the NRF2 pathway involvment in the cellular response against arsenic could help improve the strategies for reducing the cellular toxicity related to this metalloid. PMID:26473898

  7. Response of antioxidative enzymes to arsenic-induced phytotoxicity in leaves of a medicinal daisy, Wedelia chinensis Merrill

    PubMed Central

    Talukdar, Tulika; Talukdar, Dibyendu

    2013-01-01

    Background: Wedelia chinensis Merrill (Asteraceae) is a medicinally important herb, grown abundantly in soils contaminated with heavy metals, including toxic metalloid arsenic (As). The leaves have immense significance in treatment of various ailments. Objective: The present study was undertaken to ascertain whether the edible/usable parts experience oxidative stress in the form of membrane damage during As exposure or not. Materials and Methods: Responses of seven antioxidant enzymes were studied in leaves under 20 mg/L of As treatment in pot experiment. Results: When compared to control, activities of superoxide dismutase, monodehydroascorbatereductase, dehydroascorbatereductase, glutathione reductase, and gluathione peroxidase had increased, while the catalase level reduced and ascorbate peroxidase activity changed non-significantly in As-treated seedlings. This suggested overall positive response of antioxidant enzymes to As-induced oxidative stress. Although hydrogen peroxide content increased, level of lipid peroxidation and magnitude of membrane damage was quite normal, leading to normal growth (dry weight of shoot) of plant under Astreatment. Conclusion: W.chinensis is tolerant of As-toxicity, and thus, can be grown in As-contaminated zones. PMID:24082737

  8. Effect of copper and d-penicillamine treatment on the ocular inflammatory response and plasma antioxidant activity

    SciTech Connect

    McGahan, M.C.; Grimes, A.M. )

    1990-02-26

    Copper (Cu) complexes of a number of compounds have increased efficacy against many pathological conditions when compared to the parent compound. In the present study, the authors combined Cu treatment with daily administration of d-penicillamine (d-pen; 100 mg/kg) to determine effectiveness against the ocular inflammatory response to endotoxin. Four groups of rabbits (New Zealand white) were used in this study. Groups 1 and 2 were sham operated and Group 2 received daily injections of d-pen. Groups 3 and 4 had subcutaneously implanted osmotic pumps delivering 4.15 mg Cu per day, with Group 4 also receiving daily injections of d-pen. After 6 days of treatment the eyes were injected intravitreally with 10 ng endotoxin. Twenty-four hours later the eyes were examined, the rabbits killed and plasma and eyes obtained for analysis. There were no differences in the ocular inflammatory response between any of the groups. However, plasma antioxidant activity was significantly greater in Group IV than in any of the other groups. Plasma from groups 1-4 inhibited spontaneous lipid peroxidation by 38.9, 37.4, 54.1 and 69.2%, respectively. Increased plasma antioxidant activity in Group 4 was not due to a Cu/d-pen complex or any other compound with a molecular weight less than 10,000, but could possibly contribute to the increased anti-inflammatory efficacy of Cu/d-pen treatment found in other models of inflammation.

  9. The Cinnamon-derived Dietary Factor Cinnamic Aldehyde Activates the Nrf2-dependent Antioxidant Response in Human Epithelial Colon Cells

    PubMed Central

    Wondrak, Georg T.; Villeneuve, Nicole F.; Lamore, Sarah D.; Bause, Alexandra S.; Jiang, Tao; Zhang, Donna D.

    2011-01-01

    Colorectal cancer (CRC) is a major cause of tumor-related morbidity and mortality worldwide. Recent research suggests that pharmacological intervention using dietary factors that activate the redox sensitive Nrf2/Keap1-ARE signaling pathway may represent a promising strategy for chemoprevention of human cancer including CRC. In our search for dietary Nrf2 activators with potential chemopreventive activity targeting CRC, we have focused our studies on trans-cinnamic aldehyde (cinnamaldeyde, CA), the key flavor compound in cinnamon essential oil. Here we demonstrate that CA and an ethanolic extract (CE) prepared from Cinnamomum cassia bark, standardized for CA content by GC-MS analysis, display equipotent activity as inducers of Nrf2 transcriptional activity. In human colon cancer cells (HCT116, HT29) and non-immortalized primary fetal colon cells (FHC), CA- and CE-treatment upregulated cellular protein levels of Nrf2 and established Nrf2 targets involved in the antioxidant response including heme oxygenase 1 (HO-1) and γ-glutamylcysteine synthetase (γ-GCS, catalytic subunit). CA- and CE-pretreatment strongly upregulated cellular glutathione levels and protected HCT116 cells against hydrogen peroxide-induced genotoxicity and arsenic-induced oxidative insult. Taken together our data demonstrate that the cinnamon-derived food factor CA is a potent activator of the Nrf2-orchestrated antioxidant response in cultured human epithelial colon cells. CA may therefore represent an underappreciated chemopreventive dietary factor targeting colorectal carcinogenesis. PMID:20657484

  10. Implementation of structural response sensitivity calculations in a large-scale finite-element analysis system

    NASA Technical Reports Server (NTRS)

    Giles, G. L.; Rogers, J. L., Jr.

    1982-01-01

    The implementation includes a generalized method for specifying element cross-sectional dimensions as design variables that can be used in analytically calculating derivatives of output quantities from static stress, vibration, and buckling analyses for both membrane and bending elements. Limited sample results for static displacements and stresses are presented to indicate the advantages of analytically calclating response derivatives compared to finite difference methods. Continuing developments to implement these procedures into an enhanced version of the system are also discussed.

  11. Evaluation of antioxidant properties, elemental and phenolic contents composition of wild nettle (Urtica dioica L.) from Tunceli in Turkey.

    PubMed

    Yildirim, N C; Turkoglu, S; Ince, O K; Ince, M

    2013-01-01

    Wild nettle (Urtica dioica L.) types were sampled from different geographical regions in Tunceli (Turkey) to determine their mineral, vitamin, phenolic contents and their antioxidant properties. The total phenol varied from 37.419 ± 0.380 to 19.182 ± 1.00 mg of GAEs g(-1) of dry nettle. The highest radical scavenging effect was observed in Mazgirt parting of the ways 7.5 km with 33.70 ± 0.849 mg mL(-1). The highest reducing power was observed in the nettles from Mazgirt parting of the ways 7.5 km. Among the various macronutrients estimated in the plant samples, potassium was present in the highest quantity followed by calcium and phosphate. Kaempferol and resveratrol were not determined in some nettle samples but rutin levels were determined in all samples. Vitamin A concentrations were ranged between 13.64 ± 1.90 and 5.74 ± 1.00 (mg kg(-1) dry weight). These results show that Urtica dioica L. collected from Tunceli in Turkey could be considered as a natural alternative source for food, pharmacology and medicine sectors. PMID:24199953

  12. Role of oxidative stress in disrupting the function of negative glucocorticoid response element in daily amphetamine-treated rats.

    PubMed

    Chu, Shu-Chen; Yu, Ching-Han; Chen, Pei-Ni; Hsieh, Yih-Shou; Kuo, Dong-Yih

    2016-09-01

    Amphetamine (AMPH)-induced appetite suppression is associated with changes in hypothalamic reactive oxygen species (ROS), antioxidants, neuropeptides, and plasma glucocorticoid. This study explored whether ROS and glucocorticoid response element (GRE), which is the promoter site of corticotropin-releasing hormone (CRH) gene, participated in neuropeptides-mediated appetite control. Rats were treated daily with AMPH for four days, and changes in food intake, plasma glucocorticoid and expression levels of hypothalamic neuropeptide Y (NPY), proopiomelanocortin (POMC), superoxide dismutase (SOD), CRH, and glucocorticoid receptor (GR) were examined and compared. Results showed that food intake decreased and NPY gene down-regulated, while POMC, SOD, and CRH gene up-regulated during AMPH treatment. GR and GRE-DNA bindings were disrupted on Day 1 and Day 2 when glucocorticoid levels were still high. Pretreatment with GR inhibitor or ROS scavenger modulated mRNA levels in NPY, POMC, SOD and CRH in AMPH-treated rats. We suggest that disruptions of negative GRE (nGRE) on Day 1 and Day 2 are associated with an increase in oxidative stress during the regulation of NPY/POMC-mediated appetite control in AMPH-treated rats. These results advance the understanding of molecular mechanism in regulating AMPH-mediated appetite suppression. PMID:27235634

  13. Induction of electrophile-responsive element (EpRE)-mediated gene expression by tomato extracts in vitro.

    PubMed

    Gijsbers, Linda; van Eekelen, Henriëtte D L M; Nguyen, Thuy H; de Haan, Laura H J; van der Burg, Bart; Aarts, Jac M M J G; Rietjens, Ivonne M C M; Bovy, Arnaud G

    2012-12-01

    The market for food products with additional health benefits is increasing rapidly and tools for identification of bio-functional characteristics of food items are essential. To facilitate the detection of beneficial effects of tomato on gene expression, methods to prepare tomato extracts suitable to test in the EpRE LUX assay and other cell-based reporter gene assays for health-related bioactivity mechanisms, were developed. An isoprenoid-containing chloroform extract of tomato fruit and most individual isoprenoids did not induce electrophile-responsive element (EpRE)-mediated gene expression. A semi-polar extract of tomato fruits, enzymatically hydrolysed to remove the glycosyl residues from the phenolic ingredients was able to induce EpRE-mediated luciferase expression at both mRNA and protein level, which might be partly due to the presence of quercetin, kaempferol, naringenin and naringenin chalcone. It was concluded that induction of EpRE-regulated genes, such as detoxifying phase II and antioxidant enzymes, may contribute to the beneficial health effects of tomato.

  14. Regulatory elements responsible for inducible expression of the granulocyte colony-stimulating factor gene in macrophages.

    PubMed Central

    Nishizawa, M; Nagata, S

    1990-01-01

    Granulocyte colony-stimulating factor (G-CSF) plays an essential role in granulopoiesis during bacterial infection. Macrophages produce G-CSF in response to bacterial endotoxins such as lipopolysaccharide (LPS). To elucidate the mechanism of the induction of G-CSF gene in macrophages or macrophage-monocytes, we have examined regulatory cis elements in the promoter of mouse G-CSF gene. Analyses of linker-scanning and internal deletion mutants of the G-CSF promoter by the chloramphenicol acetyltransferase assay have indicated that at least three regulatory elements are indispensable for the LPS-induced expression of the G-CSF gene in macrophages. When one of the three elements was reiterated and placed upstream of the TATA box of the G-CSF promoter, it mediated inducibility as a tissue-specific and orientation-independent enhancer. Although this element contains a conserved NF-kappa B-like binding site, the gel retardation assay and DNA footprint analysis with nuclear extracts from macrophage cell lines demonstrated that nuclear proteins bind to the DNA sequence downstream of the NF-kappa B-like element, but not to the conserved element itself. The DNA sequence of the binding site was found to have some similarities to the LPS-responsive element which was recently identified in the promoter of the mouse class II major histocompatibility gene. Images PMID:1691438

  15. Implementation of an ANCF beam finite element for dynamic response optimization of elastic manipulators

    NASA Astrophysics Data System (ADS)

    Vohar, B.; Kegl, M.; Ren, Z.

    2008-12-01

    Theoretical and practical aspects of an absolute nodal coordinate formulation (ANCF) beam finite element implementation are considered in the context of dynamic transient response optimization of elastic manipulators. The proposed implementation is based on the introduction of new nodal degrees of freedom, which is achieved by an adequate nonlinear mapping between the original and new degrees of freedom. This approach preserves the mechanical properties of the ANCF beam, but converts it into a conventional finite element so that its nodal degrees of freedom are initially always equal to zero and never depend explicitly on the design variables. Consequently, the sensitivity analysis formulas can be derived in the usual manner, except that the introduced nonlinear mapping has to be taken into account. Moreover, the adjusted element can also be incorporated into general finite element analysis and optimization software in the conventional way. The introduced design variables are related to the cross-section of the beam, to the shape of the (possibly) skeletal structure of the manipulator and to the drive functions. The layered cross-section approach and the design element technique are utilized to parameterize the shape of individual elements and the whole structure. A family of implicit time integration methods is adopted for the response and sensitivity analysis. Based on this assumption, the corresponding sensitivity formulas are derived. Two numerical examples illustrate the performance of the proposed element implementation.

  16. Response of removable epoxy foam exposed to fire using an element death model.

    SciTech Connect

    Hobbs, Michael L.

    2004-09-01

    Response of removable epoxy foam (REF) to high heat fluxes is described using a decomposition chemistry model [1] in conjunction with a finite element heat conduction code [2] that supports chemical kinetics and dynamic radiation enclosures. The chemistry model [1] describes the temporal transformation of virgin foam into carbonaceous residue by considering breakdown of the foam polymer structure, desorption of gases not associated with the foam polymer, mass transport of decomposition products from the reaction site to the bulk gas, and phase equilibrium. The finite element foam response model considers the spatial behavior of the foam by using measured and predicted thermophysical properties in combination with the decomposition chemistry model. Foam elements are removed from the computational domain when the condensed mass fractions of the foam elements are close to zero. Element removal, referred to as element death, creates a space within the metal confinement causing radiation to be the dominant mode of heat transfer between the surface of the remaining foam elements and the interior walls of the confining metal skin. Predictions were compared to front locations extrapolated from radiographs of foam cylinders enclosed in metal containers that were heated with quartz lamps [3,4]. The effects of the maximum temperature of the metal container, density of the foam, the foam orientation, venting of the decomposition products, pressurization of the metal container, and the presence or absence of embedded components are discussed.

  17. Establishing a statistic model for recognition of steroid hormone response elements.

    PubMed

    Stepanova, Maria; Lin, Feng; Lin, Valerie C-L

    2006-10-01

    Identification of hormone response elements (HREs) is essential for understanding the mechanism of hormone-regulated gene expression. To date, there has been a lack of effective bioinformatics tools for recognition of specific HRE such as Progesterone Response Elements (PRE). In this paper, a comprehensive survey and comparison of in silico methods is conducted for establishing a more accurate statistic model. Homogeneity of steroid HRE is analyzed and a reliable training dataset is constructed through extensive searching for experimentally validated response elements from more than 150 literature sources. Based on the observation that the verified HREs carry di-nucleotide preservation in comparison with uniform nucleotide distributions, both mono and di-nucleotide Position Weight Matrices are computed to extract the statistic pattern of the positions. It is followed by the sequence transition pattern recognition using a specifically designed profile Hidden Markov Model. Reciprocal combination of the statistic and transition patterns significantly improves the performance of the model in terms of higher sensitivity and specificity. Upon acquisition of the putative response elements in the promoter areas of vertebrate genes, a qualitative scheme is applied to assess the probability for each gene to be a hormone primary target. Using >650 records of experimentally validated steroid hormone response elements, a high sensitivity level of 73% and high specificity level of one prediction per 8.24 kb is reached, allowing this model to be used for further prediction of primary target genes through the analysis of their upstream promoters, for human or other vertebrate genomes of interest. Additional documents, supplementary data and the web-based program developed for response elements prediction are freely available for academic research at . Submission of putative gene promoter regions for recognition of potential regulatory PREs can be as long as 5 kb.

  18. Mortality and antioxidant responses in the planarian (Dugesia japonica) after exposure to copper.

    PubMed

    Zhang, Xiufang; Zhang, Bowen; Yi, Hongyang; Zhao, Bosheng

    2014-03-01

    The planarians (Dugesia japonica) are distributed widely in China, Japan, Korea, and southern Siberia. In this study, the acute toxicity of copper on D. japonica was evaluated using mortality and the activity of the enzymes superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GPx), and reactive oxygen species (ROS) as endpoints. Acute toxicity tests were conducted according to the American Society for Testing and Materials guidelines. The 24-, 48-, 72-, and 96-h median lethal concentration that killed 50% of individuals (LC50) were calculated as 8.70, 6.31, 4.48, and 4.23 mg Cu²⁺/L, respectively, based on measured copper concentrations. When compared with different phyla or classes of freshwater animals, the rank of D. japonica in species sensitivity was in the range of 25-26 for 96-h LC₅₀. The antioxidant enzymes SOD and CAT were determined in D. japonica exposed to two copper concentrations (50 and 100 μg Cu²⁺/L) with a short-term exposure (15 days). They all attained peak value and then reduced during the experimental period. The GPx activities were activated only for 100 μg/L treatments at days 3 and 6 and then renewed to the original level. Meanwhile, copper significantly increased the levels of ROS in D. japonica. Our study suggests that the adult D. japonica was less sensitive to copper than most other aquatic species. Copper may induce oxidative stress and interfere with the antioxidant defense system of the D. japonica, including SOD and CAT. GPx might be an insusceptible antioxidant enzyme in the metabolic detoxification processes in adult D. japonica.

  19. Antioxidant response of Stevia rebaudiana B. to polyethylene glycol and paclobutrazol treatments under in vitro culture.

    PubMed

    Hajihashemi, Shokoofeh; Ehsanpour, Ali Akbar

    2014-04-01

    This investigation was carried out with the aim of determining the effect of paclobutrazol (PBZ) (0 and 2 mg l(-1)) and polyethylene glycol (PEG) (0, 2, 4 and 6 % w/v of PEG 6000) treatments on antioxidant system of Stevia rebaudiana Bertoni under in vitro condition. Analysis of data showed that PEG treatment significantly increased hydrogen peroxide (H2O2) and phenolic contents, while PBZ treatment limited the effect of PEG on them. Our data revealed that PEG treatment significantly increased total antioxidant capacity, catalase (CAT), ascorbate peroxidase (APX), polyphenol oxidase (PPO) and peroxidase (POD) activity, while it inversely decreased glutathione reductase (GR) activity. The superoxide dismutase (SOD) activity was not affected by PEG treatment. PBZ treatment induced significantly higher levels of CAT and GR activity and lower levels of SOD activity in PEG-treated plants. PBZ in combination with PEG resulted in no significant difference on APX activity with PEG treatment alone. PBZ treatment prevented the effect of PEG on the PPO activity. PEG (with or without PBZ) treatment increased the ascorbate pool, whereas total glutathione level was not affected by PEG. Our finding indicated that PBZ reduced the negative effect of PEG treatment by quenching H2O2 accumulation and increasing the CAT activity. Collectively, the antioxidant capacity of S. rebaudiana in PEG treatment condition was associated with active enzymatic and non-enzymatic defence systems which partly could be improved by the PBZ treatment. In addition, a higher accumulation of phenolic compounds leads to a more potent reactive oxygen species scavenging activity in S. rebaudiana.

  20. Antioxidant enzyme activities of Microcystis aeruginosa in response to nonylphenols and degradation of nonylphenols by M. aeruginosa.

    PubMed

    Wang, Jingxian; Xie, Ping

    2007-10-01

    The aim of this study was to examine the effects of chemical nonylphenols (NPs) on the antioxidant system of Microcystis aeruginosa strains. The degradation and sorption of NPs by M. aeruginosa were also evaluated. High concentrations of NPs (1 and 2 mg/l) were found to cause increases in superoxidase dismutase (SOD) and glutathione-S-transferase (GST) activities and in glutathione (GSH) levels. These results suggest that toxic stress manifested by elevated SOD and GST levels and GSH contents may be responsible for the toxicity of NPs to M. aeruginosa and that the algal cells could improve their antioxidant and detoxification ability through the enhancement of enzymatic and nonenzymatic prevention substances. The observed elevations in GSH levels and GST activities were relatively higher than those in SOD activities, indicating that GSH and GST contributed more in eliminating toxic effects than SOD. Low concentrations of NPs (0.05-0.2 mg/l) enhanced cell growth and decreased GST activity in algal cells of M. aeruginosa, suggesting that NPs may have acted as a protecting factor, such as an antioxidant. The larger portion of the NPs (>60%) disappeared after 12 days of incubation, indicating the strong ability of M. aeruginosa to degrade the moderate persistent NP compounds. The sorption ratio of M. aeruginosa after a 12-day exposure to low nominal concentrations of NPs (0.02-0.5 mg/l) was relatively high (>30%). The fact that M. aeruginosa effectively resisted the toxic effects of NPs and strongly degraded these pollutants indicate that M. aeruginosa cells have a strong ability to adapt to variations in environmental conditions and that low and moderate concentrations of organic compounds may favor its survival. Further studies are needed to provide detailed information on the fate of persistent organic pollutants and the survival of algae and to determine the possible role of organic pollutants in the occurrence of water blooms in eutrophic lakes. PMID:17342429

  1. Energy and antioxidant responses of pacific oyster exposed to trace levels of pesticides.

    PubMed

    Epelboin, Yanouk; Quéré, Claudie; Pernet, Fabrice; Pichereau, Vianney; Corporeau, Charlotte

    2015-09-21

    Here, we assess the physiological effects induced by environmental concentrations of pesticides in Pacific oyster Crassostrea gigas. Oysters were exposed for 14 d to trace levels of metconazole (0.2 and 2 μg/L), isoproturon (0.1 and 1 μg/L), or both in a mixture (0.2 and 0.1 μg/L, respectively). Exposure to trace levels of pesticides had no effect on the filtration rate, growth, and energy reserves of oysters. However, oysters exposed to metconazole and isoproturon showed an overactivation of the sensing-kinase AMP-activated protein kinase α (AMPKα), a key enzyme involved in energy metabolism and more particularly glycolysis. In the meantime, these exposed oysters showed a decrease in hexokinase and pyruvate kinase activities, whereas 2-DE proteomic revealed that fructose-1,6-bisphosphatase (F-1,6-BP), a key enzyme of gluconeogenesis, was up-regulated. Activities of antioxidant enzymes were higher in oysters exposed to the highest pesticide concentrations. Both pesticides enhanced the superoxide dismutase activity of oysters. Isoproturon enhanced catalase activity, and metconazole enhanced peroxiredoxin activity. Overall, our results show that environmental concentrations of metconazole or isoproturon induced subtle changes in the energy and antioxidant metabolisms of oysters.

  2. Antioxidant status of erythrocytes and their response to oxidative challenge in humans with argemone oil poisoning

    SciTech Connect

    Babu, Challagundla K.; Khanna, Subhash K.; Das, Mukul

    2008-08-01

    Oxidative damage of biomolecules and antioxidant status in erythrocytes of humans from an outbreak of argemone oil (AO) poisoning in Kannauj (India) and AO intoxicated experimental animals was investigated. Erythrocytes of the dropsy patients and AO treated rats were found to be more susceptible to 2,2'-azobis (2-amidinopropane) dihydrochloride (AAPH) induced peroxidative stress. Significant decrease in RBC glutathione (GSH) levels (46, 63%) with concomitant enhancement in oxidized glutathione (172, 154%) levels was noticed in patients and AO intoxicated animals. Further, depletion of glutathione reductase (GR), glucose-6-phosphate dehydrogenase (G-6-PDH) and glutathione-S-transferase (GST) (42-52%) was observed in dropsy patients. Oxidation of erythrocyte membrane lipids and proteins was increased (120-144%) in patients and AO treated animals (112-137%) along with 8-OHdG levels in whole blood (180%) of dropsy patients. A significant reduction in {alpha}-tocopherol content (68%) was noticed in erythrocytes of dropsy patients and hepatic, plasma and RBCs of AO treated rats (59-70%) thereby indicating the diminished antioxidant potential to scavenge free radicals or the limited transport of {alpha}-tocopherol from liver to RBCs leading to enhanced oxidation of lipids and proteins in erythrocytes. These studies implicate an important role of erythrocyte degradation in production of anemia and breathlessness in epidemic dropsy.

  3. Free radicals and antioxidant enzymes in fish and their responses to metal pollutants

    SciTech Connect

    Zelikoff, J.T.; Flescher, E.

    1994-12-31

    Reactive oxygen intermediates (ROI) are continuously produced as metabolic by-products by virtually all tissues. Without adequate protection from these free radicals, cells/tissues can suffer significant oxidative damage. While superoxide dismutase (SOD), catalase, and NADPH-quinone reductase (QR) are well recognized antioxidant enzymes in mammalian cells, little is known concerning these enzymes in cells from aquatic species. In addition, the effects of environmental contaminants on ROI production and on these protective enzymes in fish have not been well studied. For this investigation, whole kidney cell homogenates from medaka (Oryzias latipes) were used to evaluate the activity of SOD, catalase, and QR, as well as production of the ROI`s, superoxide (O{sub 2{sup {minus}}}) and hydrogen peroxide (H{sub 2}O{sub 2}). Fish were also exposed to cadmium (Cd{sup 2+})-contaminated water at 60 ppb for five days and the effects on ROI production and these same enzyme systems were evaluated. Findings demonstrate that kidney cells from medaka stimulated in vitro with phorbol myristate acetate produced large quantities of free radicals, as well as expressed all three protective enzymes at levels comparable to those measured in mammalian immune cells. Exposure of fish to Cd{sup 2+} levels below the LC{sub 50} concentration altered these parameters. The results demonstrate the presence of antioxidant enzymes in fish immune cells and suggest the applicability of these endpoints to serve as biomarkers of aquatic metal pollution.

  4. Biochemical composition and antioxidant activities of Arthrospira (Spirulina) platensis in response to gamma irradiation.

    PubMed

    Shabana, Effat Fahmy; Gabr, Mahmoud Ali; Moussa, Helal Ragab; El-Shaer, Enas Ali; Ismaiel, Mostafa M S

    2017-01-01

    Arthrospira (Spirulina) platensis is a blue-green alga, rich with bioactive components and nutrients. To evaluate effect of gamma irradiation, A. platensis was exposed to different doses of 0.0, 0.5, 1.0, 1.5, 2.0 and 2.5kGy. The data showed that the phenolic and proline contents significantly increased with the increase of gamma irradiation doses up to 2.0kGy, above which a reduction was observed. The soluble proteins and malondialdehyde (MDA) contents were stimulated by all tested irradiation doses. Furthermore, the vitamins (A, K and B group) and mineral contents (N, P, Na, K, Ca, Mg and Fe) were stimulated by the irradiation doses compared with the control. The activities of some N-assimilating and antioxidant enzymes were significantly increased with the irradiation doses up to 2.0kGy. This study suggests the possible use of gamma irradiation as a stimulatory agent to raise the nutritive value and antioxidant activity of A. platensis. PMID:27507509

  5. Response of photosynthesis and cellular antioxidants to ozone in Populus leaves

    SciTech Connect

    Gupta, A.S.; Alscher, R.G. ); McCune, D. )

    1991-06-01

    Atmospheric ozone causes formation of various highly reactive intermediates (e.g. peroxyl and superoxide radicals, H{sub 2}O{sub 2}, etc.) in plant tissues. A plant's productivity in environments with ozone may be related to its ability to scavenge the free radicals formed. The effects of ozone on photosynthesis and some free radical scavengers were measured in the fifth emergent leaf of poplars. Clonal poplars (Populus deltoides {times} Populus cv caudina) were fumigated with 180 parts per billion ozone for 3 hours. Photosynthesis was measured before, during, and after fumigation. During the first 90 minutes of ozone exposure, photosynthetic rates were unaffected but gluthathione levels and superoxide dismutase activity increased. After 90 minutes of ozone exposure photosynthetic rates began to decline while glutathione and superoxide dismutase continued to increase. Total glutathione (reduced plus oxidized) increased in fumigated leaves throughout the exposure period. The ratio of GSH/GSSG also decreased from 12.8 to 1.2 in ozone exposed trees. Superoxide dismutase levels increased twofold in fumigated plants. After 4 hours of ozone exposure, the photosynthetic rate was approximately half that of controls while flutathione levels and superoxide dismutase activity remained above that of the controls. The elevated antioxidant levels were maintained 21 hours after ozone exposure while photosynthetic rates recovered to about 75% of that of controls. Electron transport and NADPH levels remained unaffected by the treatment. Hence, elevated antioxidant metabolism may protect the photosynthetic apparatus during exposure to ozone.

  6. Antioxidative responses during germination in quinoa grown in vitamin B-rich medium.

    PubMed

    Pitzschke, Andrea; Fraundorfer, Anna; Guggemos, Michael; Fuchs, Norbert

    2015-05-01

    Synthetic vitamin preparations have grown in popularity to combat health risks associated with an imbalanced diet, poor exercise and stress. In terms of bioavailability and diversity, they lack behind vitamins naturally occurring in plants. Solutions to obtain plant-derived vitamins at a larger scale are highly desirable. B vitamins act as precursors of enzymatic cofactors, thereby regulating important metabolic processes both in animals and plants. Because during plant germination, the vitamin content and micronutrient availability increase, sprouts are generally considered a healthier food as compared to dry grains. Germination only occurs if a plant's antioxidant machinery is sufficiently activated to cope with oxidative stress. Seeds of quinoa, an edible gluten-free plant naturally rich in minerals, germinate readily in a solution containing the eight B vitamins. We studied biochemical changes during quinoa germination, with a focus on nutritionally relevant characteristics. The results are considered from a nutritional and plant physiological perspective. Germination of quinoa in vitamin-rich medium is a promising strategy to enhance the nutritional value of this matrix. Additional health-beneficial effects indirectly resulting from the vitamin treatment include elevated levels of the multi-functional amino acid proline and a higher antioxidant capacity. Plant biomolecules can be better protected from oxidative damage in vivo. PMID:25987999

  7. Active muscle response using feedback control of a finite element human arm model.

    PubMed

    Östh, Jonas; Brolin, Karin; Happee, Riender

    2012-01-01

    Mathematical human body models (HBMs) are important research tools that are used to study the human response in car crash situations. Development of automotive safety systems requires the implementation of active muscle response in HBM, as novel safety systems also interact with vehicle occupants in the pre-crash phase. In this study, active muscle response was implemented using feedback control of a nonlinear muscle model in the right upper extremity of a finite element (FE) HBM. Hill-type line muscle elements were added, and the active and passive properties were assessed. Volunteer tests with low impact loading resulting in elbow flexion motions were performed. Simulations of posture maintenance in a gravity field and the volunteer tests were successfully conducted. It was concluded that feedback control of a nonlinear musculoskeletal model can be used to obtain posture maintenance and human-like reflexive responses in an FE HBM.

  8. Antioxidant Enzyme Responses Induced by Whiteflies in Tobacco Plants in Defense against Aphids: Catalase May Play a Dominant Role

    PubMed Central

    Zhao, Haipeng; Sun, Xia; Xue, Ming; Zhang, Xiao; Li, Qingliang

    2016-01-01

    led to the suppression of the B. tabaci mediated PR-2a expression. Conclusions/Significance Aphid resistance in plants infested with B. tabaci nymphs is associated with enhanced antioxidant activities in which CAT may play a dominant role. This resistance probably acted via interactions with SA-mediated defense responses. PMID:27788203

  9. Response of antioxidant enzymes, ascorbate and glutathione metabolism towards cadmium in hyperaccumulator and nonhyperaccumulator ecotypes of Sedum alfredii H.

    PubMed

    Jin, Xiaofen; Yang, Xiaoe; Mahmood, Qaisar; Islam, Ejazul; Liu, Dan; Li, Hong

    2008-08-01

    Hydroponics studies were conducted to investigate the antioxidant adaptations, ascorbate and glutathione metabolism in hyperaccumulating ecotype of Sedum alfredii (HE) exposed to high Cd environment, when compared with its nonhyperaccumulating ecotype (NHE). Exposure to Cd induced a burst of oxidative stress in both ecotypes which was evident by the sharp increase in hydrogen peroxide (H(2)O(2)) contents and lipid peroxidation. Buthionine sulfoximine (BSO), an inhibitor of glutathione (GSH) synthesis, did not affect H(2)O(2) concentrations as well as growth of both ecotypes in the absence of Cd. However, compared with Cd application alone, BSO combined with Cd treatment caused a substantial augmentation of H(2)O(2) accumulation accompanied by a reduction in Cd concentrations in roots and leaves of HE at the end of treatment, which may rule out the possibility that GSH biosynthesis may play an important role as a signal of the stress regulation. No efficient and superior enzymatic antioxidant defense mechanisms against Cd-imposed oxidative stress existed in both NHE and HE, but the essential nonenzymatic components like ascorbic acid (AsA) and GSH played a prominent role in tolerance against Cd. Cadmium stimulated a notable rise in AsA concentration in both ecotypes soon after the application of treatment. A preferential Cd-stress response in HE was suggested to changes in the GSH pool, where acclimation was marked by increased GSH concentrations. PMID:18214940

  10. Sensitivity and Antioxidant Response of Chlorella sp. MM3 to Used Engine Oil and Its Water Accommodated Fraction.

    PubMed

    Ramadass, Kavitha; Megharaj, Mallavarapu; Venkateswarlu, Kadiyala; Naidu, Ravi

    2016-07-01

    We exposed the microalgal strain, Chlorella sp. MM3, to unused or used engine oil, or their water accommodated fractions (WAFs) to determine growth inhibition and response of antioxidant enzymes. Oil type and oil concentration greatly affected the microalgal growth. Used oil at 0.04 % (0.4 g L(-1)) resulted in 50 % inhibition in algal growth, measured in terms of chlorophyll-a, while the corresponding concentration of unused oil was nontoxic. Similarly, used oil WAF showed significant toxicity to the algal growth at 10 % level, whereas WAF from unused oil was nontoxic even at 100 % concentration. Peroxidase enzyme in the microalga significantly increased with used oil at concentrations above 0.04 g L(-1) whereas the induction of superoxide dismutase and catalase was apparent only at 0.06 g L(-1). Activities of the antioxidant enzymes increased significantly when the microalga was exposed to 75 and 100 % WAF obtained from used oil. The used oil toxicity on microalga could be due to the presence of toxic soluble mono- and polyaromatic compounds, heavy metals, and other compounds attained by the oil during its use in the motor engines.

  11. Effect of pH and temperature on antioxidant responses of the thick shell mussel Mytilus coruscus.

    PubMed

    Hu, Menghong; Li, Lisha; Sui, Yanming; Li, Jiale; Wang, Youji; Lu, Weiqun; Dupont, Sam

    2015-10-01

    This study evaluated the combined effects of seawater pH decrease and temperature increase on the activity of antioxidant enzymes in the thick shell mussel Mytilus coruscus, an ecological and economic bivalve species widely distributed along the East China Sea. Mussels were exposed to three pH levels (8.1, 7.7 and 7.3) and two temperatures (25 °C and 30 °C) for 14 days. Activities of superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPX), glutathione (GSH), acid phosphatase (ACP), alkaline phosphatase (AKP) and glutamic-pyruvic transaminase (GPT) were measured in gills and digestive glands after 1, 3, 7 and 14 days of exposure. All enzymatic activities were significantly impacted by pH, temperature. Enzymatic activities at the high temperature were significantly higher than those at the low temperature, and the mussels exposed to pH 7.3 showed significantly higher activities than those under higher pH condition for all enzymes except ACP. There was no interaction between temperature and pH in two third of the measured activities suggesting similar mode of action for both drivers. Interaction was only consistently significant for GPX. PCA revealed positive relationships between the measured biochemical indicators in both gills and digestive glands. Overall, our results suggest that decreased pH and increased temperature induce a similar anti-oxidative response in the thick shell mussel.

  12. Responses of growth, antioxidants and gene expression in smooth cordgrass (Spartina alterniflora) to various levels of salinity.

    PubMed

    Courtney, Abigail J; Xu, Jichen; Xu, Yan

    2016-02-01

    Salinity is a major environmental factor limiting the productivity and quality of crop plants. While most cereal crops are salt-sensitive, several halophytic grasses are able to maintain their growth under saline conditions. Elucidating the mechanisms for salinity responses in halophytic grasses would contribute to the breeding of salt-tolerant cereal and turf species belonging to the Poaceae family. Smooth cordgrass (Spartina alterniflora) is a dominant native halophytic grass in the Hackensack Meadowlands, the coastal salt marshes located in northeastern New Jersey. The goals of this study were to examine the growth pattern of S. alterniflora in a salinity gradient and identify an optimal range of salinity for its maximal growth. The regulation of its antioxidant system and gene expression under supraoptimal salinity conditions was also investigated. Our results showed that a salinity of 4 parts per thousand (ppt) (68 mM) was most favorable for the growth of S. alterniflora, followed by a non-salt environment. S. alterniflora responded to salts in the environment by regulating antioxidant enzyme activities and the expression of stress-induced proteins such as ALDH, HVA22 and PEPC. The plant may tolerate salinity up to the concentration of sea water, but any salinity above 12 ppt retarded its growth and altered the expression of genes encoding critical proteins. PMID:26760954

  13. ROS-Responsive Microspheres for On Demand Antioxidant Therapy in a Model of Diabetic Peripheral Arterial Disease

    PubMed Central

    Poole, KM; Nelson, CE; Joshi, RV; Martin, JR; Gupta, MK; Haws, SC; Kavanaugh, TE; Skala, MC; Duvall, CL

    2014-01-01

    A new microparticle-based delivery system was synthesized from reactive oxygen species (ROS)-responsive poly(propylene sulfide) (PPS) and tested for “on demand” antioxidant therapy. PPS is hydrophobic but undergoes a phase change to become hydrophilic upon oxidation and thus provides a useful platform for ROS-demanded drug release. This platform was tested for delivery of the promising anti-inflammatory and antioxidant therapeutic molecule curcumin, which is currently limited in use in its free form due to poor pharmacokinetic properties. PPS microspheres efficiently encapsulated curcumin through oil-in-water emulsion and provided sustained, on demand release that was modulated in vitro by hydrogen peroxide concentration. The cytocompatible, curcumin-loaded microspheres preferentially targeted and scavenged intracellular ROS in activated macrophages, reduced in vitro cell death in the presence of cytotoxic levels of ROS, and decreased tissue-level ROS in vivo in the diabetic mouse hind limb ischemia model of peripheral arterial disease. Interestingly, due to the ROS scavenging behavior of PPS, the blank microparticles also showed inherent therapeutic properties that were synergistic with the effects of curcumin in these assays. Functionally, local delivery of curcumin-PPS microspheres accelerated recovery from hind limb ischemia in diabetic mice, as demonstrated using non-invasive imaging techniques. This work demonstrates the potential for PPS microspheres as a generalizable vehicle for ROS-demanded drug release and establishes the utility of this platform for improving local curcumin bioavailability for treatment of chronic inflammatory diseases. PMID:25522975

  14. Responses of growth, antioxidants and gene expression in smooth cordgrass (Spartina alterniflora) to various levels of salinity.

    PubMed

    Courtney, Abigail J; Xu, Jichen; Xu, Yan

    2016-02-01

    Salinity is a major environmental factor limiting the productivity and quality of crop plants. While most cereal crops are salt-sensitive, several halophytic grasses are able to maintain their growth under saline conditions. Elucidating the mechanisms for salinity responses in halophytic grasses would contribute to the breeding of salt-tolerant cereal and turf species belonging to the Poaceae family. Smooth cordgrass (Spartina alterniflora) is a dominant native halophytic grass in the Hackensack Meadowlands, the coastal salt marshes located in northeastern New Jersey. The goals of this study were to examine the growth pattern of S. alterniflora in a salinity gradient and identify an optimal range of salinity for its maximal growth. The regulation of its antioxidant system and gene expression under supraoptimal salinity conditions was also investigated. Our results showed that a salinity of 4 parts per thousand (ppt) (68 mM) was most favorable for the growth of S. alterniflora, followed by a non-salt environment. S. alterniflora responded to salts in the environment by regulating antioxidant enzyme activities and the expression of stress-induced proteins such as ALDH, HVA22 and PEPC. The plant may tolerate salinity up to the concentration of sea water, but any salinity above 12 ppt retarded its growth and altered the expression of genes encoding critical proteins.

  15. Effect of pH and temperature on antioxidant responses of the thick shell mussel Mytilus coruscus.

    PubMed

    Hu, Menghong; Li, Lisha; Sui, Yanming; Li, Jiale; Wang, Youji; Lu, Weiqun; Dupont, Sam

    2015-10-01

    This study evaluated the combined effects of seawater pH decrease and temperature increase on the activity of antioxidant enzymes in the thick shell mussel Mytilus coruscus, an ecological and economic bivalve species widely distributed along the East China Sea. Mussels were exposed to three pH levels (8.1, 7.7 and 7.3) and two temperatures (25 °C and 30 °C) for 14 days. Activities of superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPX), glutathione (GSH), acid phosphatase (ACP), alkaline phosphatase (AKP) and glutamic-pyruvic transaminase (GPT) were measured in gills and digestive glands after 1, 3, 7 and 14 days of exposure. All enzymatic activities were significantly impacted by pH, temperature. Enzymatic activities at the high temperature were significantly higher than those at the low temperature, and the mussels exposed to pH 7.3 showed significantly higher activities than those under higher pH condition for all enzymes except ACP. There was no interaction between temperature and pH in two third of the measured activities suggesting similar mode of action for both drivers. Interaction was only consistently significant for GPX. PCA revealed positive relationships between the measured biochemical indicators in both gills and digestive glands. Overall, our results suggest that decreased pH and increased temperature induce a similar anti-oxidative response in the thick shell mussel. PMID:26235981

  16. Optimization of infrared-assisted extraction of Bletilla striata polysaccharides based on response surface methodology and their antioxidant activities.

    PubMed

    Qu, Yan; Li, Chunxue; Zhang, Chen; Zeng, Rui; Fu, Chaomei

    2016-09-01

    Bletilla striata polysaccharides (BSP) have attracted extensive research interest due to their potential medical application. Herein, infrared-assisted technique is employed for the first time to extract BSP from B. striata (Thunb.) Reichb.f. based on a Box-Behnken design (BBD) and response surface methodology, with the optimum extraction parameters as follows: 75°C extraction temperature, 2.5h extraction time; and water to solid ratio (53ml/g). Based on it, 43.95±0.26% yield of crude BSP was obtained. Subsequently, crude BSP was further decolorized, deproteinized, freeze-dried, and purified by a DEAE-52 cellulose column. Furthermore, the micro-structure and a triple-helical structure of BSP were characterized. Fourier transform infrared spectra confirmed its polysaccharide characterization via typical peaks. In addition, the significant in vitro antioxidant profiles of BSP were demonstrated by superoxide anion radical-scavenging assay, hydroxyl radical scavenging assay, DPPH free radical scavenging activity and chelation of ferrous ions. Taken together, this study provide an efficient extraction technique for BSP as a promising natural antioxidant. PMID:27185148

  17. Effect of benfluralin on Pinus pinea seedlings mycorrhized with Pisolithus tinctorius and Suillus bellinii--study of plant antioxidant response.

    PubMed

    Franco, Albina R; Pereira, Sofia I A; Castro, Paula M L

    2015-02-01

    In this study, Pinus pinea seedlings mycorrhized with selected ectomycorrhizal fungi (ECMF), Pisolithus tinctorius and Suillus bellinii, were exposed to the herbicide benfluralin. Non-mycorrhized P. pinea seedlings and seedlings mycorrhized with ECMF were transferred to benfluralin-spiked soils at levels of 0.165, 1.65 and 16.5 mg kg(-1). Plant growth and the fungal role on plant antioxidant response were assessed. In the presence of benfluralin, higher plant growth was observed in mycorrhized plants compared to non-mycorrhized plants, but ECMF colonisation and nutrient uptake were affected by the herbicide. Benfluralin showed no effect on lipid peroxidation in P. pinea seedlings. However, seedlings mycorrhized with S. bellinii showed higher levels of lipid peroxidation when compared to non-mycorrhized ones, both in the presence and absence of benfluralin. The increase of lipid peroxidation could be related to seedling growth induced by the fungus and not to benfluralin toxicity. A similar trend was observed in seedlings mycorrhized with P. tinctorius when exposed to higher benfluralin concentrations, suggesting that the antioxidant response to benfluralin is related not only to fungus species, but also to the level of stress applied in the soil. The higher amount of superoxide dismutase activity in P. pinea seedlings tissues exposed to benfluralin could indicate a plant adaptative response to benfluralin toxicity. Catalase activity showed no increase with benfluralin exposure. Pre-established P. tinctorius mycorrhization conferred root protection and enhanced plant growth in benfluralin spiked soil, inferring that P. tinctorius - P. pinea association could advantageous for plant growth in soils contaminated with pesticides.

  18. Pounding Effects on the Earthquake Response of Adjacent Reinforced Concrete Structures Strengthened by Cable Elements

    NASA Astrophysics Data System (ADS)

    Liolios, Angelos; Liolios, Asterios; Hatzigeorgiou, George; Radev, Stefan

    2014-06-01

    A numerical approach for estimating the effects of pounding (seismic interaction) on the response of adjacent Civil Engineering structures is presented. Emphasis is given to reinforced concrete (RC) frames of existing buildings which are seismically strengthened by cable-elements. A double discretization, in space by the Finite Element Method and in time by a direct incremental approach is used. The unilateral behaviours of both, the cable-elements and the interfaces contact-constraints, are taken strictly into account and result to inequality constitutive conditions. So, in each time-step, a non-convex linear complementarity problem is solved. It is found that pounding and cable strengthening have significant effects on the earthquake response and, hence, on the seismic upgrading of existing adjacent RC structures.

  19. Are collapsars responsible for some r-process elements? How could we tell?

    SciTech Connect

    Pruet, J

    2004-04-05

    We consider the possibility that supernovae which form hyper-accreting black holes might be responsible for synthesis of r-process elements with mass A {approx}< 130. Calculations are presented which show that these elements are naturally synthesized in neutron-rich magnetically-dominated bubbles born in the inner regions of a black hole accretion disk. Simple considerations suggest that the total mass ejected in the form of these bubbles is about that needed to account for the entire galactic inventory of the 2nd-peak r-process elements. We also argue that if collapsars are responsible for, e.g., Ag synthesis, then Ag abundances should be correlated with Sc and/or Zn abundances in metal-poor stars.

  20. Response of hot element flush wall gauges in oscillating laminar flow

    NASA Technical Reports Server (NTRS)

    Giddings, T. A.; Cook, W. J.

    1986-01-01

    The time dependent response characteristics of flush-mounted hot element gauges used as instruments to measure wall shear stress in unsteady periodic air flows were investigated. The study was initiated because anomalous results were obtained from the gauges in oscillating turbulent flows for the phase relation of the wall shear stress variation, indicating possible gauge response problems. Flat plate laminar oscillating turbulent flows characterized by a mean free stream velocity with a superposed sinusoidal variation were performed. Laminar rather than turbulent flows were studied, because a numerical solution for the phase angle between the free stream velocity and the wall shear stress variation that is known to be correct can be obtained. The focus is on comparing the phase angle indicated by the hot element gauges with corresponding numerical prediction for the phase angle, since agreement would indicate that the hot element gauges faithfully follow the true wall shear stress variation.

  1. Investigating the functionality of an OCT4-short response element in human induced pluripotent stem cells.

    PubMed

    Vega-Crespo, Agustin; Truong, Brian; Hermann, Kip J; Awe, Jason P; Chang, Katherine M; Lee, Patrick C; Schoenberg, Benjamen E; Wu, Lily; Byrne, James A; Lipshutz, Gerald S

    2016-01-01

    Pluripotent stem cells offer great therapeutic promise for personalized treatment platforms for numerous injuries, disorders, and diseases. Octamer-binding transcription factor 4 (OCT4) is a key regulatory gene maintaining pluripotency and self-renewal of mammalian cells. With site-specific integration for gene correction in cellular therapeutics, use of the OCT4 promoter may have advantages when expressing a suicide gene if pluripotency remains. However, the human OCT4 promoter region is 4 kb in size, limiting the capacity of therapeutic genes and other regulatory components for viral vectors, and decreasing the efficiency of homologous recombination. The purpose of this investigation was to characterize the functionality of a novel 967bp OCT4-short response element during pluripotency and to examine the OCT4 titer-dependent response during differentiation to human derivatives not expressing OCT4. Our findings demonstrate that the OCT4-short response element is active in pluripotency and this activity is in high correlation with transgene expression in vitro, and the OCT4-short response element is inactivated when pluripotent cells differentiate. These studies demonstrate that this shortened OCT4 regulatory element is functional and may be useful as part of an optimized safety component in a site-specific gene transferring system that could be used as an efficient and clinically applicable safety platform for gene transfer in cellular therapeutics. PMID:27500178

  2. Investigating the functionality of an OCT4-short response element in human induced pluripotent stem cells

    PubMed Central

    Vega-Crespo, Agustin; Truong, Brian; Hermann, Kip J; Awe, Jason P; Chang, Katherine M; Lee, Patrick C; Schoenberg, Benjamen E; Wu, Lily; Byrne, James A; Lipshutz, Gerald S

    2016-01-01

    Pluripotent stem cells offer great therapeutic promise for personalized treatment platforms for numerous injuries, disorders, and diseases. Octamer-binding transcription factor 4 (OCT4) is a key regulatory gene maintaining pluripotency and self-renewal of mammalian cells. With site-specific integration for gene correction in cellular therapeutics, use of the OCT4 promoter may have advantages when expressing a suicide gene if pluripotency remains. However, the human OCT4 promoter region is 4 kb in size, limiting the capacity of therapeutic genes and other regulatory components for viral vectors, and decreasing the efficiency of homologous recombination. The purpose of this investigation was to characterize the functionality of a novel 967bp OCT4-short response element during pluripotency and to examine the OCT4 titer-dependent response during differentiation to human derivatives not expressing OCT4. Our findings demonstrate that the OCT4-short response element is active in pluripotency and this activity is in high correlation with transgene expression in vitro, and the OCT4-short response element is inactivated when pluripotent cells differentiate. These studies demonstrate that this shortened OCT4 regulatory element is functional and may be useful as part of an optimized safety component in a site-specific gene transferring system that could be used as an efficient and clinically applicable safety platform for gene transfer in cellular therapeutics. PMID:27500178

  3. Responses of Trace Elements to Aerobic Maximal Exercise in Elite Sportsmen

    PubMed Central

    OTAĞ, Aynur; HAZAR, Muhsin; OTAĞ, İlhan; Gürkan, Alper Cenk; Okan, İlyas

    2014-01-01

    Trace elements are chemical elements needed in minute quantities for the proper growth, development, and physiology of the organism. In biochemistry, a trace element is also referred to as a micronutrient. Trace elements, such as nickel, cadmium, aluminum, silver, chromium, molybdenum, germanium, tin, titanium, tungsten, scandium, are found naturally in the environment and human exposure derives from a variety of sources, including air, drinking water and food. The Purpose of this study was investigated the effect of aerobic maximal intensity endurance exercise on serum trace elements as well-trained individuals of 28 wrestlers (age (year) 19.64±1.13, weight (Kg) 70.07 ± 15.69, height (cm) 176.97 ± 6.69) during and after a 2000 meter Ergometer test protocol was used to perform aerobic (75 %) maximal endurance exercise. Trace element serum levels were analyzed from blood samples taken before, immediately after and one hour after the exercise. While an increase was detected in Chromium (Cr), Nickel (Ni), Molybdenum (Mo) and Titanium (Ti) serum levels immediately after the exercise, a decrease was detected in Aluminum (Al), Scandium (Sc) and Tungsten (W) serum levels. Except for aluminum, the trace elements we worked on showed statistically meaningful responses (P<0.05 and P<0.001). According to the responses of trace elements to the exercise showed us the selection and application of the convenient sport is important not only in terms of sportsman performance but also in terms of future healthy life plans and clinically. PMID:24762350

  4. Experimental measurement of tympanic membrane response for finite element model validation of a human middle ear.

    PubMed

    Ahn, Tae-Soo; Baek, Moo-Jin; Lee, Dooho

    2013-01-01

    The middle ear consists of a tympanic membrane, ligaments, tendons, and three ossicles. An important function of the tympanic membrane is to deliver exterior sound stimulus to the ossicles and inner ear. In this study, the responses of the tympanic membrane in a human ear were measured and compared with those of a finite element model of the middle ear. A laser Doppler vibrometer (LDV) was used to measure the dynamic responses of the tympanic membrane, which had the measurement point on the cone of light of the tympanic membrane. The measured subjects were five Korean male adults and a cadaver. The tympanic membranes were stimulated using pure-tone sine waves at 18 center frequencies of one-third octave band over a frequency range of 200 Hz ~10 kHz with 60 and 80 dB sound pressure levels. The measured responses were converted into the umbo displacement transfer function (UDTF) with a linearity assumption. The measured UDTFs were compared with the calculated UDTFs using a finite element model for the Korean human middle ear. The finite element model of the middle ear consists of three ossicles, a tympanic membrane, ligaments, and tendons. In the finite element model, the umbo displacements were calculated under a unit sound pressure on the tympanic membrane. The UDTF of the finite element model exhibited good agreement with that of the experimental one in low frequency range, whereas in higher frequency band, the two response functions deviated from each other, which demonstrates that the finite element model should be updated with more accurate material properties and/or a frequency dependent material model.

  5. Uterine deletion of Trp53 compromises antioxidant responses in mouse decidua

    SciTech Connect

    Burnum, Kristin E.; Hirota, Yasushi; Baker, Erin Shammel; Yoshie, Mikihiro; Ibrahim, Yehia M.; Monroe, Matthew E.; Anderson, Gordon A.; Smith, Richard D.; Daikoku, Takiko; Dey, Sudhansu K.

    2012-09-01

    Preterm birth is a global health issue impacting both mothers and children. However, the etiology of preterm birth is not clearly understood. From our recent finding that premature decidual senescence with terminal differentiation is a cause of preterm birth in mice with uterine Trp53 deletion, encoding p53 protein, led us to explore other potential factors that are related to preterm birth. Utilizing proteomics approaches, here we show that 183 candidate proteins cause significant changes in decidua with Trp53 deletion as compared to normal decidua. Functional categorization of these proteins unveiled new pathways that are influenced by p53. In particular, downregulation of a cluster of antioxidant proteins in p53 deficient decidua suggests that increased oxidative stress could be one cause of preterm birth in mice with uterine deletion of Trp53.

  6. Uterine deletion of Trp53 compromises antioxidant responses in the mouse decidua.

    PubMed

    Burnum, Kristin E; Hirota, Yasushi; Baker, Erin S; Yoshie, Mikihiro; Ibrahim, Yehia M; Monroe, Matthew E; Anderson, Gordon A; Smith, Richard D; Daikoku, Takiko; Dey, Sudhansu K

    2012-09-01

    Preterm birth is a global health issue impacting millions of mothers and babies. However, the etiology of preterm birth is not clearly understood. Our recent finding that premature decidual senescence with terminal differentiation is a cause of preterm birth in mice with uterine Trp53 deletion, encoding p53 protein, led us to explore other potential factors that are related to preterm birth. Using proteomics approaches, here, we show that 183 candidate proteins show significant changes in deciduae with Trp53 deletion as compared with normal deciduae. Functional categorization of these proteins unveiled new pathways that are influenced by p53. In particular, down-regulation of a cluster of antioxidant enzymes in p53-deficient deciduae suggests that increased oxidative stress could be one cause of preterm birth in mice harboring uterine deletion of Trp53. PMID:22759378

  7. Uterine Deletion of Trp53 Compromises Antioxidant Responses in the Mouse Decidua

    PubMed Central

    Burnum, Kristin E.; Hirota, Yasushi; Baker, Erin S.; Yoshie, Mikihiro; Ibrahim, Yehia M.; Monroe, Matthew E.; Anderson, Gordon A.; Smith, Richard D.; Daikoku, Takiko

    2012-01-01

    Preterm birth is a global health issue impacting millions of mothers and babies. However, the etiology of preterm birth is not clearly understood. Our recent finding that premature decidual senescence with terminal differentiation is a cause of preterm birth in mice with uterine Trp53 deletion, encoding p53 protein, led us to explore other potential factors that are related to preterm birth. Using proteomics approaches, here, we show that 183 candidate proteins show significant changes in deciduae with Trp53 deletion as compared with normal deciduae. Functional categorization of these proteins unveiled new pathways that are influenced by p53. In particular, down-regulation of a cluster of antioxidant enzymes in p53-deficient deciduae suggests that increased oxidative stress could be one cause of preterm birth in mice harboring uterine deletion of Trp53. PMID:22759378

  8. Cadmium-induced physiological response and antioxidant enzyme changes in the novel cadmium accumulator, Tagetes patula.

    PubMed

    Liu, Yu-Ting; Chen, Zueng-Sang; Hong, Chwan-Yang

    2011-05-30

    The accumulation and effect of cadmium (Cd) on the growth and enzymatic activities changes of antioxidants in Tagetes patula, French marigold, were investigated to reveal the physiological mechanisms corresponding to its Cd tolerance and accumulation. Hydroponically grown T. patula plants were treated with different concentrations of Cd (0, 10, 25, 50 μM Cd Cl(2)) at various regime of times. T. patula accumulated Cd to a maximum of 450 mg Cd kg(-1) dry weight (DW) in shoot and 3500 mg Cd kg(-1) DW in root after 14 days' exposure at 10 and 50 μM Cd Cl(2), respectively. The translocation factors of Cd were greater than 1 in plants exposed to 10 μM Cd Cl(2). Toxic effects were gradually observed with increasing Cd concentration (25 and 50 μM) accompanied with the reduction of biomass, chlorophyll content, decrease of cell viability and the increase level of lipid peroxidation. In leaves of T. patula, the activities of ascorbate peroxidase (APX), glutathione reductase (GR) and superoxide dismutase (SOD) were induced by Cd. However, in roots, activities of APX, GR, SOD and catalase (CAT) were significantly reduced by 25 and 50 μM Cd treatment but not 10 μM Cd. In-gel zymography analysis revealed that Cd induced the enzymatic activities of APX, MnSOD, CuZnSOD and different isozymes of GR in leaves. These results indicate that T. patula is a novel Cd accumulator and able to tolerate with Cd-induced toxicity by activation of its antioxidative defense system. PMID:21458916

  9. Response of mitochondrial antioxidant system and respiratory pathways to reactive nitrogen species in pea leaves.

    PubMed

    Martí, María C; Florez-Sarasa, Igor; Camejo, Daymi; Pallol, Beatriz; Ortiz, Ana; Ribas-Carbó, Miquel; Jiménez, Ana; Sevilla, Francisca

    2013-02-01

    Nitric oxide (NO) has emerged as an important signaling molecule in plants, but little is known about the effects of reactive nitrogen species in plant mitochondria. In this study, the effects of DETA-NONOate, a pure NO slow generator, and of SIN-1 (3-morpholinosydnonimine), a peroxynitrite producer, on the activities of respiratory pathways, enzymatic and non-enzymatic antioxidants have been investigated in isolated mitochondria from pea leaves. No significant changes in lipid peroxidation, protein oxidation or in ascorbate and glutathione redox state were observed after DETA-NONOate treatments whereas cytochrome pathway (CP) respiration was reversibly inhibited and alternative pathway (AP) respiration showed little inhibition. On the other hand, NO did not affect neither activities of Mn superoxide dismutase (Mn-SOD) nor enzymes involved in the ascorbate and glutathione regeneration in mitochondria except for ascorbate peroxidase (APX), which was reversely inhibited depending on ascorbate concentration. Finally, SIN-1 treatment of mitochondria produced a decrease in CP respiration, an increase in protein oxidation and strongly inhibited APX activity (90%), with glutathione reductase and dehydroascorbate reductase (DHAR) being moderately inhibited (30 and 20%, respectively). This treatment did not affect monodehydroascorbate reductase (MDHAR) and Mn-SOD activities. Results showed that mitochondrial nitrosative stress was not necessarily accompanied by oxidative stress. We suggest that NO-resistant AP and mitochondrial APX may be important components of the H(2) O(2) -signaling pathways under nitrosative stress induced by NO in this organelle. Also, MDHAR and DHAR, via ascorbate regeneration, could constitute an essential antioxidant defense together with Mn-SOD, against NO and ONOO(-) stress in plant mitochondria.

  10. Responses of bovine lymphocytes to heat shock as modified by breed and antioxidant status.

    PubMed

    Kamwanja, L A; Chase, C C; Gutierrez, J A; Guerriero, V; Olson, T A; Hammond, A C; Hansen, P J

    1994-02-01

    We tested whether resistance of lymphocytes to heat stress is modified by breed, intracellular glutathione content, and extracellular antioxidants. In the first experiment, lymphocytes from Angus (Bos taurus, non-heat-tolerant), Brahman (B. indicus, heat-tolerant), and Senepol (B. taurus, heat-tolerant) heifers (12 heifers per breed) were cultured at 45 degrees C for 3 h to evaluate thermal killing, at 42 degrees C for 12 h in a 60-h phytohemagglutinin-induced proliferation test, and at 42 degrees C for 1 h to measure induction of heat shock protein 70 (HSP70). Killing at 45 degrees C was affected by breed x temperature (P < .01); the decrease in viability caused by a temperature of 45 degrees C was greater for Angus than for Brahman or Senepol. For phytohemagglutinin-stimulated lymphocytes, heating to 42 degrees C reduced [3H]thymidine incorporation equally for all breeds. Viability at the end of culture was affected (P < .001) by a breed x temperature interaction because the decrease in viability caused by culture at 42 degrees C was greatest for lymphocytes from Angus heifers. Heat shock for 1 h at 42 degrees C caused a two- to threefold increase in intracellular concentrations of HSP70, but there was no interaction of temperature with breed. In another experiment (with lymphocytes harvested from three Holstein cows), buthionine sulfoximine, a glutathione synthesis inhibitor, inhibited (P < .01) proliferation of phytohemagglutinin-stimulated lymphocytes at 38.5 and 42 degrees C. Addition of the antioxidants glutathione or thioredoxin to culture did not reduce the effects of heating to 42 degrees C on proliferation.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:8157528

  11. Antioxidative response to Cd in a newly discovered cadmium hyperaccumulator, Arabis paniculata F.

    PubMed

    Qiu, Rong-Liang; Zhao, Xuan; Tang, Ye-Tao; Yu, Fang-Ming; Hu, Peng-Jie

    2008-12-01

    A hydroponic experiment was carried out to study the effect of cadmium (Cd) on growth, Cd accumulation, lipid peroxidation, reactive oxygen species (ROS) content and antioxidative enzymes in leaves and roots of Arabis paniculata F., a new Cd hyperaccumuator found in China. The results showed that 22-89 microM Cd in solution enhanced the growth of A. paniculata after three weeks, with 21-27% biomass increase compared to the control. Cd concentrations in shoots and roots increased with increasing Cd supply levels, and reached a maximum of 1662 and 8670 mg kg(-1) Cd dry weight at 178 microM Cd treatment, respectively. In roots, 22-89 microM Cd reduced the content of malondialdehyde (MDA), superoxide (O(2)(-1)) and H(2)O(2) as well as the activities of superoxide dismutase (SOD), guaiacol peroxidase (GPX), ascorbate peroxidase (APX) and glutathione reductase (GR). In leaves, the contents of MDA, O(2)(-1) and H(2)O(2) remained unaffected by 22-89 microM Cd, while 178 microM Cd treatment significantly increased the MDA content, 69.5% higher than that of the control; generally, the activities of SOD, catalase (CAT), GPX and APX showed an increasing pattern with increasing Cd supply levels. Our present work concluded that A. paniculata has a great capability of Cd tolerance and accumulation. Moderate Cd treatment (22-89 microM Cd) alleviated the oxidative stress in roots, while higher level of Cd addition (178 microM) could cause an increasing generation of ROS, which was effectively scavenged by the antioxidative system. PMID:18992910

  12. Competitive apnea diving sessions induces an adaptative antioxidant response in mononucleated blood cells.

    PubMed

    Sureda, A; Batle, J M; Tur, J A; Pons, A

    2015-09-01

    The aim was evaluating the effects of hypoxia/reoxygenation repetitive episodes during 5 days of apnea diving (3-day training/2-day competition) on peripheral blood mononuclear cells (PBMCs) antioxidant defenses, oxidative damage, and plasma xanthine oxidase activity. Blood samples, from seven professional apnea divers, were taken under basal conditions the previous morning to the first training session (pre-diving basal), 4 h after ending the competition (4 h post-diving) and the following morning (15 h after last dive) in basal conditions (post-diving basal). Glucose levels significantly decreased whereas triglycerides increased at 4 h post-diving, both returning to basal values at post-diving basal. Glutathione reductase and catalase activity significantly increased after 4 h post-diving remaining elevated at post-diving basal. Glutathione peroxidase and superoxide dismutase activities and catalase protein levels progressively increased after diving with significant differences respect to initial values at post-diving basal. No significant differences were observed in circulating PBMCs and oxidative damage markers. Plasma xanthine oxidase activity and nitrite levels, but not the inducible nitric oxide synthetase, significantly increased 4 h post-diving, returning to the basal values after 15 h. In conclusion, chronic and repetitive episodes of diving apnea during five consecutive days increased plasma xanthine oxidase activity and nitric oxide production which could enhance the signalling role of reactive oxygen and nitrogen species for PBMCs antioxidant adaptation against hypoxia/reoxygenation.

  13. Comparative biochemical responses and antioxidant activities of the rabbit urinary bladder to whole grapes versus resveratrol.

    PubMed

    Francis, Johdi-Ann; Leggett, Robert E; Schuler, Catherine; Levin, Robert M

    2015-12-01

    The objective of this study is to compare the antioxidant activity of a whole-grape suspension with the antioxidant activity or pure resveratrol on the effect of hydrogen peroxide (H2O2) on malondialdehyde (MDA) generation, choline acetyltransferase (ChAT) activity, calcium ATPase activity, and sarcoendoplasmic reticular ATPase (SERCA) of the male rabbit urinary bladder. MDA was used as a model for the effect of H2O2 on lipid peroxidation. ChAT, SERCA, and calcium ATPase were evaluated based on their importance in urinary bladder physiology and pathology. Four male rabbit bladders were used. Each bladder was separated into muscle and mucosa, frozen under liquid nitrogen and stored at -80 °C for biochemical evaluation. The effect of H2O2 on the enzymes listed above was determined in the presence and absence of either resveratrol or a whole-grape suspension. (1) Resveratrol was significantly more effective than the grape suspension at protecting the bladder muscle and mucosa against peroxidation as quantitated by MDA formation. (2) The grape suspension was significantly more effective at protecting ChAT activity against oxidative stress of the muscle than resveratrol. (3) Neither the grape suspension nor resveratrol were particularly effective at protecting the bladder muscle or mucosa calcium ATPase or SERCA against oxidative stress. (4) ChAT was significantly more sensitive to oxidative stress than either calcium ATPase or SERCA. These data support the idea that the grape suspension protects the mitochondria and nerve terminals to a significantly greater degree than resveratrol which suggests that the activities of the grape suspension are due to the combination of active components found in the grape suspension and not just resveratrol alone.

  14. Evaluation of pollution in Camichin estuary (Mexico): pro-oxidant and antioxidant response in oyster (Crassostrea corteziensis).

    PubMed

    Girón-Pérez, M I; Romero-Bañuelos, C A; Toledo-Ibarra, G A; Rojas-García, A E; Medina-Diaz, I M; Robledo-Marenco, M L; Vega-López, A

    2013-08-01

    The physiological system of molluscs, particularly pro-oxidant and antioxidant mechanisms, could be altered by pollutants and induce disturbance on health status and productive parameters of aquatic organisms, such as oyster. Therefore, the aim of this study was to evaluate the chemical contamination in water (total metals and polycyclic aromatic hydrocarbons) and oxidative stress parameters in oysters (Crassostrea corteziensis) in Camichin estuary, located in Mexican Tropical Pacific. The results obtained showed the presence of arsenic, lead and zinc, as well as naphthalene, pyrene and benzo[a]pyrene in concentrations relatively higher than criteria established by local and international guidelines. Regarding the biomarkers of oxidative stress response (H2O2 and O2 concentration, catalase activity, lipid peroxidation, and hydroperoxide concentration), differences between oyster from estuary and control group were significant. These results indicate that these pollutants could be related with oxidative stress detected in oyster. PMID:23500622

  15. The effect of loading time on flexible pavement dynamic response: a finite element analysis

    NASA Astrophysics Data System (ADS)

    Yin, Hao; Solaimanian, Mansour; Kumar, Tanmay; Stoffels, Shelley

    2007-12-01

    Dynamic response of asphalt concrete (AC) pavements under moving load is a key component for accurate prediction of flexible pavement performance. The time and temperature dependency of AC materials calls for utilizing advanced material characterization and mechanistic theories, such as viscoelasticity and stress/strain analysis. In layered elastic analysis, as implemented in the new Mechanistic-Empirical Pavement Design Guide (MEPDG), the time dependency is accounted for by calculating the loading times at different AC layer depths. In this study, the time effect on pavement response was evaluated by means of the concept of “pseudo temperature.” With the pavement temperature measured from instrumented thermocouples, the time and temperature dependency of AC materials was integrated into one single factor, termed “effective temperature.” Via this effective temperature, pavement responses under a transient load were predicted through finite element analysis. In the finite element model, viscoelastic behavior of AC materials was characterized through relaxation moduli, while the layers with unbound granular material were assumed to be in an elastic mode. The analysis was conducted for two different AC mixtures in a simplified flexible pavement structure at two different seasons. Finite element analysis results reveal that the loading time has a more pronounced impact on pavement response in the summer for both asphalt types. The results indicate that for reasonable prediction of dynamic response in flexible pavements, the effect of the depth-dependent loading time on pavement temperature should be considered.

  16. Pharmacokinetics and pharmacodynamics of phase II drug metabolizing/antioxidant enzymes gene response by anticancer agent sulforaphane in rat lymphocytes.

    PubMed

    Wang, Hu; Khor, Tin Oo; Yang, Qian; Huang, Ying; Wu, Tien-Yuan; Saw, Constance Lay-Lay; Lin, Wen; Androulakis, Ioannis P; Kong, Ah-Ng Tony

    2012-10-01

    This study assesses the pharmacokinetics (PK) and pharmacodynamics (PD) of Nrf2-mediated increased expression of phase II drug metabolizing enzymes (DME) and antioxidant enzymes which represents an important component of cancer chemoprevention in rat lymphocytes following intravenous (iv) administration of an anticancer phytochemical sulforaphane (SFN). SFN was administered intravenously to four groups of male Sprague-Dawley JVC rats each group comprising four animals. Blood samples were drawn at selected time points. Plasma were obtained from half of each of the blood samples and analyzed using a validated LC-MS/MS method. Lymphocytes were collected from the remaining blood samples using Ficoll-Paque Plus centrifuge medium. Lymphocyte RNAs were extracted and converted to cDNA, quantitative real-time PCR analyses were performed, and fold changes were calculated against those at time zero for the relative expression of Nrf2-target genes of phase II DME/antioxidant enzymes. PK-PD modeling was conducted based on Jusko's indirect response model (IDR) using GastroPlus and bootstrap method. SFN plasma concentration declined biexponentially and the pharmacokinetic parameters were generated. Rat lymphocyte mRNA expression levels showed no change for GSTM1, SOD, NF-κB, UGT1A1, or UGT1A6. Moderate increases (2-5-fold) over the time zero were seen for HO-1, Nrf2, and NQO1, and significant increases (>5-fold) for GSTT1, GPx1, and Maf. PK-PD analyses using GastroPlus and the bootstrap method provided reasonable fitting for the PK and PD profiles and parameter estimates. Our present study shows that SFN could induce Nrf2-mediated phase II DME/antioxidant mRNA expression for NQO1, GSTT1, Nrf2, GPx, Maf, and HO-1 in rat lymphocytes after iv administration, suggesting that Nrf2-mediated mRNA expression in lymphocytes may serve as surrogate biomarkers. The PK-PD IDR model simultaneously linking the plasma concentrations of SFN and the PD response of lymphocyte mRNA expression is

  17. Heat-shock response and antioxidant defense during air exposure in Patagonian shallow-water limpets from different climatic habitats.

    PubMed

    Pöhlmann, Kevin; Koenigstein, Stefan; Alter, Katharina; Abele, Doris; Held, Christoph

    2011-11-01

    Climate warming involves not only a rise of air temperature means, but also more frequent heat waves in many regions on earth, and is predicted to intensify physiological stress especially in extremely changeable habitats like the intertidal. We investigated the heat-shock response (HSR) and enzymatic antioxidant defense levels of Patagonian shallow-water limpets, adapted to distinct tidal exposure conditions in the sub- and intertidal. Limpets were sampled in the temperate Northern Patagonia and the subpolar Magellan region. Expression levels of two Hsp70 genes and activities of the antioxidants superoxide dismutase (SOD) and catalase (CAT) were measured in submerged and 2- and 12-h air-exposed specimens. Air-exposed Patagonian limpets showed a tiered HSR increasing from South to North on the latitudinal gradient and from high to low shore levels on a tidal gradient. SOD activities in the Magellan region correlated with the tidal rhythm and were higher after 2 and 12 h when the tide was low at the experimental site compared to the 6 h value taken at high tide. This pattern was observed in intertidal and subtidal specimens, although subtidal individuals are little affected by tides. Our study shows that long-term thermal adaptation shapes the HSR in limpets, while the oxidative stress response is linked to the tidal rhythm. Close to the warm border of their distribution range, energy expenses to cope with stress might become overwhelming and represent one cause why the limpets are unable to colonize the shallow intertidal zone.

  18. Lung antioxidant and cytokine responses to coarse and fine particulate matter from the great California wildfires of 2008.

    PubMed

    Wegesser, Teresa C; Franzi, Lisa M; Mitloehner, Frank M; Eiguren-Fernandez, Arantza; Last, Jerold A

    2010-06-01

    The authors have previously demonstrated that wildfire-derived coarse or fine particulate matter (PM) intratracheally instilled into lungs of mice induce a strong inflammatory response. In the current study, the authors demonstrate that wildfire PM simultaneously cause major increases in oxidative stress in the mouse lungs as measured by decreased antioxidant content of the lung lavage supernatant fluid 6 and 24 h after PM administration. Concentrations of neutrophil chemokines/cytokines and of tumor necrosis factor (TNF)-alpha were elevated in the lung lavage fluid obtained 6 and 24 h after PM instillation, consistent with the strong neutrophilic inflammatory response observed in the lungs 24 h after PM administration, suggesting a relationship between the proinflammatory activity of the PM and the measured level of antioxidant capacity in the lung lavage fluid. Chemical analysis shows relatively low levels of polycyclic aromatic hydrocarbons compared to published results from typical urban PM. Coarse PM fraction is more active (proinflammatory activity and oxidative stress) on an equal-dose basis than the fine PM despite its lower content of polycyclic aromatic hydrocarbons. There does not seem to be any correlation between the content of any specific polycyclic aromatic hydrocarbon (or of total polycyclic aromatic hydrocarbon content) in the PM fraction and its toxicity. However, the concentrations of the oxidation products of phenanthrene and anthracene, phenanthraquinone and anthraquinone, were several-fold higher in the coarse PM than the fine fraction, suggesting a significant role for atmospheric photochemistry in the formation of secondary pollutants in the wildfire PM and the possibility that such secondary pollutants could be significant sources of toxicity in the wildfire PM.

  19. Mycorrhizal-induced calmodulin mediated changes in antioxidant enzymes and growth response of drought-stressed trifoliate orange

    PubMed Central

    Huang, Yong-Ming; Srivastava, A. K.; Zou, Ying-Ning; Ni, Qiu-Dan; Han, Yu; Wu, Qiang-Sheng

    2014-01-01

    Trifoliate orange [Poncirus trifoliata (L) Raf.] is considered highly arbuscular mycorrhizal (AM) dependent for growth responses through a series of signal transductions in form of various physiological responses. The proposed study was carried out to evaluate the effect of an AM fungus (Funneliformis mosseae) on growth, antioxidant enzyme (catalase, CAT; superoxide dismutase, SOD) activities, leaf relative water content (RWC), calmodulin (CaM), superoxide anion (O2•−), and hydrogen peroxide (H2O2) concentrations in leaves of the plants exposed to both well-watered (WW) and drought stress (DS) conditions. A 58-day of DS significantly decreased mycorrhizal colonization by 60% than WW. Compared to non-AM seedlings, AM seedlings displayed significantly higher shoot morphological properties (plant height, stem diameter, and leaf number), biomass production (shoot and root fresh weight) and leaf RWC, regardless of soil water status. AM inoculation significantly increased CaM and soluble protein concentrations and CAT activity, whereas significantly decreased O2•− and H2O2 concentration under both WW and DS conditions. The AM seedlings also exhibited significantly higher Cu/Zn-SOD and Mn-SOD activities than the non-AM seedlings under DS but not under WW, which are triggered by higher CaM levels in AM plants on the basis of correlation studies. Further, the negative correlation of Cu/Zn-SOD and Mn-SOD activities with O2•− and H2O2 concentration showed the DS-induced ROS scavenging ability of CaM mediated SODs under mycorrhization. Our results demonstrated that AM-inoculation elevated the synthesis of CaM in leaves and up-regulated activities of the antioxidant enzymes, thereby, repairing the possible oxidative damage to plants by lowering the ROS accumulation under DS condition. PMID:25538696

  20. Lead detoxification by coontail (Ceratophyllum demersum L.) involves induction of phytochelatins and antioxidant system in response to its accumulation.

    PubMed

    Mishra, Seema; Srivastava, S; Tripathi, R D; Kumar, R; Seth, C S; Gupta, D K

    2006-11-01

    Coontail (Ceratophyllum demersum L.) plants when exposed to various concentrations of Pb (1-100microM) for 1-7days, exhibited both phytotoxic and tolerance responses. The specific responses were function of concentration and duration. Plants accumulated 1748mugPbg(-1) dw after 7d which reflected its metal accumulation ability, however most of the metal (1222microgg(-1) dw, 70%) was accumulated after 1d exposure only. The toxic effect and oxidative stress caused by Pb were evident by the reduction in biomass and photosynthetic pigments and increase in malondialddehyde (MDA) content and electrical conductivity with increase in metal concentration and exposure duration. Morphological symptoms of senescence phenomena such as chlorosis and fragmentation of leaves were observed after 7d. The metal tolerance and detoxification strategy adopted by the plant was investigated with reference to antioxidant system and synthesis of phytochelatins. Protein and antioxidant enzymes viz., superoxide dismutase (SOD, EC 1.15.1.1), guaiacol peroxidase (GPX, EC 1.11.1.7) ascorbate peroxidase (APX, EC 1.11.1.11), catalase (CAT, EC 1.11.1.6) and glutathione reductase (GR, EC 1.6.4.2) showed induction at lower concentration and duration followed by decline. All enzymes except GPX showed maximum activity after 1d. An increase in cysteine, non-protein thiols (NP-SH) and glutathione (GSH) content was observed at moderate exposure conditions followed by decline. Phytochelatins (PC(2) and PC(3)) were synthesized to significant levels at 10 and 50microM Pb with concomitant decrease in GSH levels. Thus production of PCs seems important for the detoxification of metal, however it may lead to depletion of GSH and consequently oxidative stress. Results suggest that plants responded positively to moderate Pb concentrations and accumulated high amount of metal. Due to metal accumulation coupled with detoxification potential, the plant appears to have potential for its use as phytoremediator species

  1. The MYC 3' Wnt-Responsive Element Drives Oncogenic MYC Expression in Human Colorectal Cancer Cells.

    PubMed

    Rennoll, Sherri A; Eshelman, Melanie A; Raup-Konsavage, Wesley M; Kawasawa, Yuka Imamura; Yochum, Gregory S

    2016-01-01

    Mutations in components of the Wnt/β-catenin signaling pathway drive colorectal cancer (CRC) by deregulating expression of downstream target genes including the c-MYC proto-oncogene (MYC). The critical regulatory DNA enhancer elements that control oncogenic MYC expression in CRC have yet to be fully elucidated. In previous reports, we correlated T-cell factor (TCF) and β-catenin binding to the MYC 3' Wnt responsive DNA element (MYC 3' WRE) with MYC expression in HCT116 cells. Here we used CRISPR/Cas9 to determine whether this element is a critical driver of MYC. We isolated a clonal population of cells that contained a deletion of a single TCF binding element (TBE) within the MYC 3' WRE. This deletion reduced TCF/β-catenin binding to this regulatory element and decreased MYC expression. Using RNA-Seq analysis, we found altered expression of genes that regulate metabolic processes, many of which are known MYC target genes. We found that 3' WRE-Mut cells displayed a reduced proliferative capacity, diminished clonogenic growth, and a decreased potential to form tumors in vivo. These findings indicate that the MYC 3' WRE is a critical driver of oncogenic MYC expression and suggest that this element may serve as a therapeutic target for CRC. PMID:27223305

  2. Endothelial responses of magnesium and other alloying elements in magnesium-based stent materials

    PubMed Central

    Zhao, Nan; Zhu, Donghui

    2016-01-01

    Biodegradable tailored magnesium (Mg) alloys are some of the most promising scaffolds for cardiovascular stents. During the course of degradation after implantation, all the alloying elements in the scaffold will be released to the surrounding vascular tissues. However, fundamental questions regarding the toxicity of alloying elements towards vascular cells, the maximum amount of each element that could be used in alloy design, or how each of the alloying elements affects vascular cellular activity and gene expression, are still not fully answered. This work systematically addressed these questions by revealing how application of different alloying elements commonly used in Mg stent materials influences several indices of human endothelial cell health, i.e., viability, proliferations, cytoskeletal reorganizations, migration, and the gene expression profile. The overall cell viability and proliferation showed a decreasing trend with increasing concentrations of the ions, and the half maximal effective concentrations (EC50) for each element were determined. When applied at a low concentration of around 10 mM, Mg had no adverse effects but improved cell proliferation and migration instead. Mg ions also altered endothelial gene expression significantly in a dose dependent manner. Most of the changed genes are related to angiogenesis and the cell adhesion signaling pathways. Findings from this work provide useful information on maximum safe doses of these ions for endothelial cells, endothelial responses towards these metal ions, and some guidance for future Mg stent design. PMID:25363018

  3. Antioxidant Response of Osteoblasts to Doxycycline in an Inflammatory Model Induced by C-reactive Protein and Interleukin-6

    PubMed Central

    Tilakaratne, A.; Soory, Mena

    2016-01-01

    Objectives: Investigation of osteoblastic responses to oxidative stress, induced by C-reactive protein (CRP) and IL-6 and ameliorating effects of doxycycline (Dox); using assays for 5-alpha dihydrotestosterone (DHT) as an antioxidant marker of healing. IL-6 and CRP are risk markers of periodontitis and prevalent comorbidities in periodontitis subjects. Methods: Confluent monolayer cultures of osteoblasts were incubated with radiolabelled testosterone (14C-T) as substrate, in the presence or absence (Control) of pre-determined optimal concentrations of CRP, IL-6, Dox; alone and in combination (n=8) for 24h in MEM. The eluent was solvent-extracted for steroid metabolites. They were separated using TLC in a benzene/ acetone solvent system 4:1 v/v; and quantified using radioisotope scanning. The identity of formed metabolites was confirmed using the mobility of cold standards added to the samples and disclosed in iodine. Further confirmation of the authenticity of DHT was carried out by combined gas chromatrography-mass spectrometry, after derivatization to pentafluorobenzyloxime trimethyl silyl ether. Results: The yields of DHT from 14C-testosterone showed 2-fold and 1.8-fold- inhibition in response to IL-6 and CRP respectively and 28% stimulation in response to Dox, via the 5-alpha reductase pathway. The combination of IL-6 + CRP showed a 2-fold reduction in the yields of DHT, elevated to control values when combined with Dox (n=8; p<0.001). Yields of 4-androstenedione showed an inverse relationship to those of DHT, in response to the agents tested, in keeping with the 17-beta hydroxysteroid dehydrogenase pathway. Conclusions: Inhibition of DHT synthesis in osteoblasts by IL-6 and CRP was overcome by doxycycline. Oxidative actions of IL-6 and CRP; and antioxidant actions of Dox are reinforced by the metabolic yields of DHT in response to agents tested. Using a novel metabolically active model allows closer extrapolation to in vivo conditions; in the context of

  4. Elemental responses to subduction-zone metamorphism: Constraints from the North Qilian Mountain, NW China

    NASA Astrophysics Data System (ADS)

    Xiao, Yuanyuan; Niu, Yaoling; Song, Shuguang; Davidson, Jon; Liu, Xiaoming

    2013-02-01

    Subduction zone metamorphism (SZM) and behaviors of chemical elements in response to this process are important for both arc magmatism and mantle compositional heterogeneity. In this paper, we report the results of our petrographic and geochemical studies on blueschist and eclogite facies rocks of sedimentary and basaltic protoliths from two metamorphic sub-belts with different metamorphic histories in the North Qilian Mountain, Northwest China. The protolith of low-grade blueschists is basaltic in composition and is most likely produced in a back-arc setting, while the protoliths of high-grade blueschists/eclogites geochemically resemble the present-day normal and enriched mid-oceanic ridge basalts plus some volcanic arc rocks. The meta-sedimentary rocks, including meta-graywacke, meta-pelite, meta-chert and marble, show geochemical similarity to global oceanic (subducted) sediments. Assuming that high field strength elements (HFSEs) are relatively immobile, the correlated variations of rare earth elements (REEs) and Th with HFSEs suggest that all these elements are probably also immobile, whereas Pb and Sr are mobile in rocks of both basaltic and sedimentary protoliths during SZM. Ba, Cs and Rb are immobile in rocks of sedimentary protoliths and mobile in rocks of basaltic protolith. The apparent mobility of U in rocks of basaltic protolith may be inherited from seafloor alterations rather than caused by SZM. On the basis of in situ mineral compositional analysis (both major and trace elements), the most significant trace element storage minerals in these subduction-zone metamorphic rocks are: lawsonite, pumpellyite, apatite, garnet and epidote group minerals for REEs, white micas (both phengite and paragonite) for large ion lithophile elements, rutile and titanite for HFSEs. The presence and stability of these minerals exert the primary controls on the geochemical behaviors of most of these elements during SZM. The immobility of REEs, Th and U owing to their

  5. High Salinity Induces Different Oxidative Stress and Antioxidant Responses in Maize Seedlings Organs

    PubMed Central

    AbdElgawad, Hamada; Zinta, Gaurav; Hegab, Momtaz M.; Pandey, Renu; Asard, Han; Abuelsoud, Walid

    2016-01-01

    Salinity negatively affects plant growth and causes significant crop yield losses world-wide. Maize is an economically important cereal crop affected by high salinity. In this study, maize seedlings were subjected to 75 mM and 150 mM NaCl, to emulate high soil salinity. Roots, mature leaves (basal leaf-pair 1,2) and young leaves (distal leaf-pair 3,4) were harvested after 3 weeks of sowing. Roots showed the highest reduction in biomass, followed by mature and young leaves in the salt-stressed plants. Concomitant with the pattern of growth reduction, roots accumulated the highest levels of Na+ followed by mature and young leaves. High salinity induced oxidative stress in the roots and mature leaves, but to a lesser extent in younger leaves. The younger leaves showed increased electrolyte leakage (EL), malondialdehyde (MDA), and hydrogen peroxide (H2O2) concentrations only at 150 mM NaCl. Total antioxidant capacity (TAC) and polyphenol content increased with the increase in salinity levels in roots and mature leaves, but showed no changes in the young leaves. Under salinity stress, reduced ascorbate (ASC) and glutathione (GSH) content increased in roots, while total tocopherol levels increased specifically in the shoot tissues. Similarly, redox changes estimated by the ratio of redox couples (ASC/total ascorbate and GSH/total glutathione) showed significant decreases in the roots. Activities of enzymatic antioxidants, catalase (CAT, EC 1.11.1.6) and dehydroascorbate reductase (DHAR, EC 1.8.5.1), increased in all organs of salt-treated plants, while superoxide dismutase (SOD, EC 1.15.1.1), ascorbate peroxidase (APX, EC 1.11.1.11), glutathione-s-transferase (GST, EC 2.5.1.18) and glutathione reductase (GR, EC 1.6.4.2) increased specifically in the roots. Overall, these results suggest that Na+ is retained and detoxified mainly in roots, and less stress impact is observed in mature and younger leaves. This study also indicates a possible role of ROS in the systemic

  6. Effects of diphenyl diselenide on growth, oxidative damage, and antioxidant response in silver catfish.

    PubMed

    Menezes, Charlene; Marins, Aline; Murussi, Camila; Pretto, Alexandra; Leitemperger, Jossiele; Loro, Vania Lucia

    2016-01-15

    The aim of this study was to evaluate the effects of dietary diphenyl diselenide [(PhSe)2] at different concentrations (1.5, 3.0, and 5.0 mg/kg) on growth, oxidative damage and antioxidant parameters in silver catfish after 30 and 60 days. Fish fed with 5.0 mg/kg of (PhSe)2 experienced a significant decrease in weight, length, and condition factor after 30 days and these parameters increased after 60 days. Thiobarbituric acid reactive substances (TBARS) and protein carbonyl (PC) decreased in the liver of silver catfish supplemented with (PhSe)2 after 30 days at all concentrations, while after 60 days these parameters decreased in liver, gills, brain, and muscle. Supplementation with (PhSe)2 induced a decrease in catalase (CAT) activity from liver only after 60 days of feeding. Superoxide dismutase (SOD) decreased at 5.0 mg/kg after 30 and 60 days and glutathione peroxidase (GPx) was enhanced at 1.5 and 3.0 mg/kg after 30 and 60 days. Silver catfish supplemented for 30 days showed a significant increase in liver glutathione S-transferase (GST) at 3.0 mg/kg, while after 60 days GST activity increased in liver at 1.5, 3.0, and 5.0 mg/kg and in gills at 3.0 and 5.0 mg/kg of (PhSe)2. After 30 days, non-protein thiols (NPSH) did not change, while after 60 days NPSH increased in liver, gills, brain, and muscle. In addition, ascorbic acid (AA) levels after 30 days increased in liver at three concentrations and in gills and muscle at 1.5 mg/kg, while after 60 days, AA increased at all concentrations in all and tissues tested. Thus, diet supplemented with (PhSe)2 for 60 days could be more effective for silver catfish. Although the concentration of 5.0 mg/kg showed decreased growth parameters, concentrations of 1.5 and 3.0 mg/kg, in general, decreased oxidative damage and increased antioxidant defenses. PMID:26520260

  7. Creating diversified response profiles from a single quenchometric sensor element by using phase-resolved luminescence.

    PubMed

    Tehan, Elizabeth C; Bukowski, Rachel M; Chodavarapu, Vamsy P; Titus, Albert H; Cartwright, Alexander N; Bright, Frank V

    2015-01-05

    We report a new strategy for generating a continuum of response profiles from a single luminescence-based sensor element by using phase-resolved detection. This strategy yields reliable responses that depend in a predictable manner on changes in the luminescent reporter lifetime in the presence of the target analyte, the excitation modulation frequency, and the detector (lock-in amplifier) phase angle. In the traditional steady-state mode, the sensor that we evaluate exhibits a linear, positive going response to changes in the target analyte concentration. Under phase-resolved conditions the analyte-dependent response profiles: (i) can become highly non-linear; (ii) yield negative going responses; (iii) can be biphasic; and (iv) can exhibit super sensitivity (e.g., sensitivities up to 300 fold greater in comparison to steady-state conditions).

  8. Creating Diversified Response Profiles from a Single Quenchometric Sensor Element by Using Phase-Resolved Luminescence

    PubMed Central

    Tehan, Elizabeth C.; Bukowski, Rachel M.; Chodavarapu, Vamsy P.; Titus, Albert H.; Cartwright, Alexander N.; Bright, Frank V.

    2015-01-01

    We report a new strategy for generating a continuum of response profiles from a single luminescence-based sensor element by using phase-resolved detection. This strategy yields reliable responses that depend in a predictable manner on changes in the luminescent reporter lifetime in the presence of the target analyte, the excitation modulation frequency, and the detector (lock-in amplifier) phase angle. In the traditional steady-state mode, the sensor that we evaluate exhibits a linear, positive going response to changes in the target analyte concentration. Under phase-resolved conditions the analyte-dependent response profiles: (i) can become highly non-linear; (ii) yield negative going responses; (iii) can be biphasic; and (iv) can exhibit super sensitivity (e.g., sensitivities up to 300 fold greater in comparison to steady-state conditions). PMID:25569752

  9. Antioxidant Expression Response to Free Radicals in Active Men and Women Fallowing to a Session Incremental Exercise; Numerical Relationship Between Antioxidants and Free Radicals

    PubMed Central

    Baghaiee, Behrouz; Aliparasti, Mohammad Reza; Almasi, Shohreh; Siahkuhian, Marefat; Baradaran, Behzad

    2016-01-01

    Background Energy production is a necessary process to continue physical activities, and exercise is associated with more oxygen consumption and increase of oxidative stress. what seems important is the numerical relationship between antioxidant and free radicals. Although the activity of some enzymes increases with physical activities, but it is possible that gene expression of this enzyme is not changed during exercise. Objectives The aim of the present study is to investigate the antioxidant enzymes gene expression and changes in malondialdehyde (MDA) and total antioxidant capacity (TAC) levels in men and women affected by a session of incremental exercise and to carefully and numerically assess the relationship between MDA changes and gene expression and activity of antioxidant enzymes. Materials and Methods 12 active men and 12 active women (21 - 24 years old) participated voluntarily in this study. Peripheral blood samples were taken from the subjects in three phases, before and after graduated exercise test (GXT) and 3 hours later (recovery). Results The gene expression of manganese superoxide dismutase (MnSOD) enzyme increased significantly in women in the recovery phase (P < 0.05). Catalase gene expression significantly increased in men in both phases (immediately & recovery) (P < 0.05). But the changes in active women were only significant immediately after the exercise. TAC levels increased significantly in men in the recovery phase and in active women immediately after the exercise (P < 0.05). MDA activity also increased significantly in men in both phases (P < 0.05). However, in women the increase was significant only in the recovery phase (P < 0.05). There was a reverse relationship between changes in MnSOD and copper- and zinc-containing superoxide dismutase (Cu/ZnSOD) levels and MDA in men (P < 0.05). In active women there was also a significant relationship between changes in MDA and gene expression of Cu/ZnSOD and TAC (P < 0.05). Conclusions The

  10. Antioxidant Expression Response to Free Radicals in Active Men and Women Fallowing to a Session Incremental Exercise; Numerical Relationship Between Antioxidants and Free Radicals

    PubMed Central

    Baghaiee, Behrouz; Aliparasti, Mohammad Reza; Almasi, Shohreh; Siahkuhian, Marefat; Baradaran, Behzad

    2016-01-01

    Background Energy production is a necessary process to continue physical activities, and exercise is associated with more oxygen consumption and increase of oxidative stress. what seems important is the numerical relationship between antioxidant and free radicals. Although the activity of some enzymes increases with physical activities, but it is possible that gene expression of this enzyme is not changed during exercise. Objectives The aim of the present study is to investigate the antioxidant enzymes gene expression and changes in malondialdehyde (MDA) and total antioxidant capacity (TAC) levels in men and women affected by a session of incremental exercise and to carefully and numerically assess the relationship between MDA changes and gene expression and activity of antioxidant enzymes. Materials and Methods 12 active men and 12 active women (21 - 24 years old) participated voluntarily in this study. Peripheral blood samples were taken from the subjects in three phases, before and after graduated exercise test (GXT) and 3 hours later (recovery). Results The gene expression of manganese superoxide dismutase (MnSOD) enzyme increased significantly in women in the recovery phase (P < 0.05). Catalase gene expression significantly increased in men in both phases (immediately & recovery) (P < 0.05). But the changes in active women were only significant immediately after the exercise. TAC levels increased significantly in men in the recovery phase and in active women immediately after the exercise (P < 0.05). MDA activity also increased significantly in men in both phases (P < 0.05). However, in women the increase was significant only in the recovery phase (P < 0.05). There was a reverse relationship between changes in MnSOD and copper- and zinc-containing superoxide dismutase (Cu/ZnSOD) levels and MDA in men (P < 0.05). In active women there was also a significant relationship between changes in MDA and gene expression of Cu/ZnSOD and TAC (P < 0.05). Conclusions The

  11. Antioxidants Abrogate Alpha-Tocopherylquinone-Mediated Down-Regulation of the Androgen Receptor in Androgen-Responsive Prostate Cancer Cells

    PubMed Central

    Fajardo, Alexandra M.; MacKenzie, Debra A.; Olguin, Sarah L.; Scariano, John K.; Rabinowitz, Ian; Thompson, Todd A.

    2016-01-01

    Tocopherylquinone (TQ), the oxidation product of alpha-tocopherol (AT), is a bioactive molecule with distinct properties from AT. In this study, AT and TQ are investigated for their comparative effects on growth and androgenic activity in prostate cancer cells. TQ potently inhibited the growth of androgen-responsive prostate cancer cell lines (e.g., LAPC4 and LNCaP cells), whereas the growth of androgen-independent prostate cancer cells (e.g., DU145 cells) was not affected by TQ. Due to the growth inhibitory effects induced by TQ on androgen-responsive cells, the anti-androgenic properties of TQ were examined. TQ inhibited the androgen-induced activation of an androgen-responsive reporter and inhibited the release of prostate specific antigen from LNCaP cells. TQ pretreatment was also found to inhibit AR activation as measured using the Multifunctional Androgen Receptor Screening assay. Furthermore, TQ decreased androgen-responsive gene expression, including TM4SF1, KLK2, and PSA over 5-fold, whereas AT did not affect the expression of androgen-responsive genes. Of importance, the antiandrogenic effects of TQ on prostate cancer cells were found to result from androgen receptor protein down-regulation produced by TQ that was not observed with AT treatment. Moreover, none of the androgenic endpoints assessed were affected by AT. The down-regulation of androgen receptor protein by TQ was abrogated by co-treatment with antioxidants. Overall, the biological actions of TQ were found to be distinct from AT, where TQ was found to be a potent inhibitor of cell growth and androgenic activity in androgen-responsive prostate cancer cells. PMID:26986969

  12. Phytoremediation of phenol using Vicia sativa L. plants and its antioxidative response.

    PubMed

    Ibáñez, Sabrina G; Sosa Alderete, Lucas G; Medina, María I; Agostini, Elizabeth

    2012-06-01

    Common vetch (Vicia sativa L.) is a legume species with an extensive agricultural use. However, the phytoremediation potentiality of this species has not been sufficiently explored because little is known about its resistance to inorganic and organic pollutants. In the present work, phenol tolerance of common vetch was assayed at different stages of growth. Germination index and germination rate decreased only at high phenol concentrations (250 and 500 mg L(-1)), whereas 30-day-old plants were able to tolerate this pollutant, with high removal efficiencies. The activities of antioxidative enzymes, such as peroxidase (POD) and ascorbate peroxidase, increased significantly with the highest phenol concentration, whereas superoxide dismutase activity, malondialdehyde, and H(2)O(2) levels remained unaltered. Besides, an increase in two basic isoforms of POD was observed in plants treated with phenol. The results suggested that common vetch has an efficient protection mechanism against phenol-induced oxidative damage. Moreover, it could tolerate and remove high phenol concentrations, avoiding serious phytotoxic effects. Thus, V. sativa could be considered an interesting tool in the field of phytoremediation.

  13. Ultraviolet-B light induced oxidative stress: effects on antioxidant response of Spodoptera litura.

    PubMed

    Karthi, Sengodan; Sankari, R; Shivakumar, Muthugounder S

    2014-06-01

    Ultraviolet light (UV-B), which emits radiation in the range of 280-315 nm, has been used worldwide in light trapping of insect pests. In this article, we test the hypothesis that one of the duration of UV-B exposure has a differential impact on oxidative stress marker enzymes in Spodoptera litura. Effect of UV-B exposure on total protein and antioxidant activities of superoxide dismutase (SOD), catalase (CAT), peroxidases (POX) and glutathione-S-transferase (GST) were investigated in S. litura. The adults were exposed to UV-B light for various time periods (0, 30, 60, 90 and 120 min). We found that exposure to UV-B light for 30 and 60 min resulted in increased activities of POX. When the exposure time lasted for 60 and 90 min, the activities of SOD remained significantly higher than the control. However, the POX, CAT and GST activity decreased to control levels at 90 and 120 min. whereas relatively long duration exposure activates the xenobiotics detoxifying enzymes like GST and POX and CAT enzymes. Longer UV-B exposure may interfere with pesticide detoxification mechanism in insects, making them more susceptible to insecticides.

  14. Temperature affects Hg-induced antioxidant responses in Chinese rare minnow Gobiocypris rarus larvae in vitro.

    PubMed

    Li, Zhi-Hua; Li, Ping; Chen, Lu

    2014-12-01

    The effect of temperature on HgCl2 (Hg(2+))-induced oxidative stress to Chinese rare minnow (Gobiocypris rarus) was evaluated in vitro. Malondialdehyde (MDA) content and superoxide dismutase, catalase and glutathione peroxidase activities were determined in whole body homogenates incubated with 0.1 mg/L Hg(2+) at 15, 25 and 35°C for 60 min. The result showed that oxidative stress was at a normal level in the Hg(2+) + NT (0.1 mg/L Hg(2+) and normal temperature, 25°C) and Hg(2+) + LT (0.1 mg/L Hg(2+) and low temperature, 15°C) groups, but a significant induction in oxidative stress occurred in the Hg(2+) + HT (35°C) group. This was reflected by an increased level of MDA and decreased activities of the antioxidant enzymes. The results suggest that higher temperature enhances heavy metal toxicity in aquatic systems, which should be given more attention in the future. PMID:25323039

  15. Antioxidant responses and bioaccumulation in green-lipped mussels (Perna viridis) under acute tributyltin chloride exposure.

    PubMed

    Chen, Hai-Gang; Jia, Xiao-Ping; Cai, Wen-Gui; Lin, Qin; Ma, Sheng-Wei

    2011-11-01

    Green-lipped mussels (Perna viridis) were exposed to waterborne tributyltin chloride (TBTCl) at different concentrations (0.2, 0.4 and 0.8 μg L(-1)) for up to 72 h. Accumulated TBTCl in Perna viridis correlated linearly with the exposure concentrations of 0.2 μg L(-1)(R(2) = 0.772), 0.4 μg L(-1)(R(2) = 0.952), and 0.8 μg L(-1)(R(2) = 0.909). The results of superoxide dismutase (SOD), glutathione peroxidase (GPx) and malondialdehyde (MDA) all decreased in gill tissues after 24 h of exposure, but the hepatic SOD and the hepatic GPx showed either little or no effect on exposure of TBTCl solutions. Analysis using the Spearman rank correlation coefficient showed the hepatic GPx activity appeared to have a significant negative correlativity (R(s) = -0.42) with the exposed TBTCl concentrations, and the hepatic MDA was significantly negatively correlated (R(s) = -0.33) with the tissue TBTCl concentrations. Conversely, a significant positive correlation (R(s) = 0.60) was shown between the gill MDA contents and exposure time. This study illustrates oxyradical scavenger GPx best correlated with stress level of pollutants among the various antioxidant parameters.

  16. Effects of light intensity on growth, immune responses, antioxidant capability and disease resistance of juvenile blunt snout bream Megalobrama amblycephala.

    PubMed

    Tian, Hong-Yan; Zhang, Ding-Dong; Xu, Chao; Wang, Fei; Liu, Wen-Bin

    2015-12-01

    Light is necessary for many fish species to develop and grow normally since most fishes are visual feeders. However, too intense light may be stressful or even lethal. Thus, this study was conducted to evaluate the effect of light intensity on growth, immune response, antioxidant capability and disease resistance of juvenile blunt snout bream Megalobrama amblycephala. Fish (18.04 ± 0.22 g) randomly divided into 5 groups were exposed to a range of light intensities (100, 200, 400, 800 and 1600 lx) in cultures for 8 weeks. After the feeding trial, fish were challenged by Aeromonas hydrophila and cumulative mortality was recorded for the next 96 h. The results demonstrated that fish subjected to 400 lx showed the greatest weight gain (125.70 ± 5.29%). Plasma levels of glucose and lactate increased with light intensity rising from 100 lx to 1600 lx while the lowest plasma levels of cortisol was observed at 400 lx group. Post-challenged haemato-immunological parameters (including plasma lysozyme and alternative complement activities, as well as plasma nitric oxide level and globulin contents) improved with light intensity increasing from 100 lx to 400 lx, and then decreased with further increasing light intensity. However, antioxidant biomarkers such as liver catalase and malondialdehyde showed an opposite trend with immune response with the lowest values observed at 400 lx groups. The application of light intensity at 1600 lx significantly lowered liver glutathione activity to 76.78 ± 6.91 μmol g(-1). Within a range of light intensity from 100 to 400 lx, no differences were observed in liver total superoxide dismutase and glutathione peroxidase activities while they were significantly higher at 800 and 1600 lx. After challenge, the lowest mortality was observed in fish exposed to 400 lx. It was significantly lower than that of fish exposed to 100 and 1600 lx. The results of the present study indicated that high light intensities (more than 800 lx) not only produced

  17. Effects of light intensity on growth, immune responses, antioxidant capability and disease resistance of juvenile blunt snout bream Megalobrama amblycephala.

    PubMed

    Tian, Hong-Yan; Zhang, Ding-Dong; Xu, Chao; Wang, Fei; Liu, Wen-Bin

    2015-12-01

    Light is necessary for many fish species to develop and grow normally since most fishes are visual feeders. However, too intense light may be stressful or even lethal. Thus, this study was conducted to evaluate the effect of light intensity on growth, immune response, antioxidant capability and disease resistance of juvenile blunt snout bream Megalobrama amblycephala. Fish (18.04 ± 0.22 g) randomly divided into 5 groups were exposed to a range of light intensities (100, 200, 400, 800 and 1600 lx) in cultures for 8 weeks. After the feeding trial, fish were challenged by Aeromonas hydrophila and cumulative mortality was recorded for the next 96 h. The results demonstrated that fish subjected to 400 lx showed the greatest weight gain (125.70 ± 5.29%). Plasma levels of glucose and lactate increased with light intensity rising from 100 lx to 1600 lx while the lowest plasma levels of cortisol was observed at 400 lx group. Post-challenged haemato-immunological parameters (including plasma lysozyme and alternative complement activities, as well as plasma nitric oxide level and globulin contents) improved with light intensity increasing from 100 lx to 400 lx, and then decreased with further increasing light intensity. However, antioxidant biomarkers such as liver catalase and malondialdehyde showed an opposite trend with immune response with the lowest values observed at 400 lx groups. The application of light intensity at 1600 lx significantly lowered liver glutathione activity to 76.78 ± 6.91 μmol g(-1). Within a range of light intensity from 100 to 400 lx, no differences were observed in liver total superoxide dismutase and glutathione peroxidase activities while they were significantly higher at 800 and 1600 lx. After challenge, the lowest mortality was observed in fish exposed to 400 lx. It was significantly lower than that of fish exposed to 100 and 1600 lx. The results of the present study indicated that high light intensities (more than 800 lx) not only produced

  18. An Extended Finite Element Method Formulation for Modeling the Response of Polycrystalline Materials to Dynamic Loading

    NASA Astrophysics Data System (ADS)

    Robbins, Joshua; Voth, Thomas E.

    2007-12-01

    The eXtended Finite Element Method (X-FEM) is a finite-element based discretization technique developed originally to model dynamic crack propagation [1]. Since that time the method has been used for modeling physics ranging from static meso-scale material failure to dendrite growth. Here we adapt the recent advances of Vitali and Benson [2] and Song et al. [3] to model dynamic loading of a polycrystalline material. We use demonstration problems to examine the method's efficacy for modeling the dynamic response of polycrystalline materials at the meso-scale. Specifically, we use the X-FEM to model grain boundaries. This approach allows us to i) eliminate ad-hoc mixture rules for multi-material elements and ii) avoid explicitly meshing grain boundaries.

  19. Amplification of Distant Estrogen Response Elements Deregulates Target Genes Associated with Tamoxifen Resistance in Breast Cancer

    PubMed Central

    Hsu, Pei-Yin; Hsu, Hang-Kai; Lan, Xun; Juan, Liran; Yan, Pearlly S.; Labanowska, Jadwiga; Heerema, Nyla; Hsiao, Tzu-Hung; Chiu, Yu-Chiao; Chen, Yidong; Liu, Yunlong; Li, Lang; Li, Rong; Thompson, Ian M.; Nephew, Kenneth P.; Sharp, Zelton D.; Kirma, Nameer B.; Jin, Victor X.; Huang, Tim H.-M.

    2013-01-01

    SUMMARY A causal role of gene amplification in tumorigenesis is well-known, while amplification of DNA regulatory elements as an oncogenic driver remains unclear. In this study, we integrated next-generation sequencing approaches to map distant estrogen response elements (DEREs) that remotely control transcription of target genes through chromatin proximity. Two densely mapped DERE regions located on chromosomes 17q23 and 20q13 were frequently amplified in ERα-positive luminal breast cancer. These aberrantly amplified DEREs deregulated target gene expression potentially linked to cancer development and tamoxifen resistance. Progressive accumulation of DERE copies was observed in normal breast progenitor cells chronically exposed to estrogenic chemicals. These findings may extend to other DNA regulatory elements, the amplification of which can profoundly alter target transcriptome during tumorigenesis. PMID:23948299

  20. Antioxidative responses of the tissues of two wild populations of Pelophylax kl. esculentus frogs to heavy metal pollution.

    PubMed

    Prokić, Marko D; Borković-Mitić, Slavica S; Krizmanić, Imre I; Mutić, Jelena J; Vukojević, Vesna; Nasia, Mohammed; Gavrić, Jelena P; Despotović, Svetlana G; Gavrilović, Branka R; Radovanović, Tijana B; Pavlović, Slađan Z; Saičić, Zorica S

    2016-06-01

    on the results in this study, we concluded that increased concentrations of heavy metals in frog tissues can alter the AOS, which leads to higher concentrations of GSH and SH groups and lower activities of antioxidative enzymes. The response of the AOS to metal pollutants allowed us to make a distinction between different frog tissues, and to conclude that the liver and skin are more suitable for assessing metal-induced oxidative stress in frogs than muscle. PMID:26874985

  1. Antioxidative responses of the tissues of two wild populations of Pelophylax kl. esculentus frogs to heavy metal pollution.

    PubMed

    Prokić, Marko D; Borković-Mitić, Slavica S; Krizmanić, Imre I; Mutić, Jelena J; Vukojević, Vesna; Nasia, Mohammed; Gavrić, Jelena P; Despotović, Svetlana G; Gavrilović, Branka R; Radovanović, Tijana B; Pavlović, Slađan Z; Saičić, Zorica S

    2016-06-01

    on the results in this study, we concluded that increased concentrations of heavy metals in frog tissues can alter the AOS, which leads to higher concentrations of GSH and SH groups and lower activities of antioxidative enzymes. The response of the AOS to metal pollutants allowed us to make a distinction between different frog tissues, and to conclude that the liver and skin are more suitable for assessing metal-induced oxidative stress in frogs than muscle.

  2. Response of the physiological parameters of mango fruit (transpiration, water relations and antioxidant system) to its light and temperature environment.

    PubMed

    Léchaudel, Mathieu; Lopez-Lauri, Félicie; Vidal, Véronique; Sallanon, Huguette; Joas, Jacques

    2013-04-15

    Depending on the position of the fruit in the tree, mango fruit may be exposed to high temperature and intense light conditions that may lead to metabolic and physiological disorders and affect yield and quality. The present study aimed to determine how mango fruit adapted its functioning in terms of fruit water relations, epicarp characteristics and the antioxidant defence system in peel, to environmental conditions. The effect of contrasted temperature and light conditions was evaluated under natural solar radiation and temperature by comparing well-exposed and shaded fruit at three stages of fruit development. The sun-exposed and shaded peels of the two sides of the well-exposed fruit were also compared. Depending on fruit position within the canopy and on the side of a well-exposed fruit, the temperature gradient over a day affected fruit characteristics such as transpiration, as revealed by the water potential gradient as a function of the treatments, and led to a significant decrease in water conductance for well-exposed fruits compared to fruits within the canopy. Changes in cuticle thickness according to fruit position were consistent with those of fruit water conductance. Osmotic potential was also affected by climatic environment and harvest stage. Environmental conditions that induced water stress and greater light exposure, like on the sunny side of well-exposed fruit, increased the hydrogen peroxide, malondialdehyde and total and reduced ascorbate contents, as well as SOD, APX and MDHAR activities, regardless of the maturity stage. The lowest values were measured in the peel of the shaded fruit, that of the shaded side of well-exposed fruit being intermediate. Mango fruits exposed to water-stress-induced conditions during growth adapt their functioning by reducing their transpiration. Moreover, oxidative stress was limited as a consequence of the increase in antioxidant content and enzyme activities. This adaptive response of mango fruit to its

  3. Responses of growth inhibition and antioxidant gene expression in earthworms (Eisenia fetida) exposed to tetrabromobisphenol A, hexabromocyclododecane and decabromodiphenyl ether.

    PubMed

    Shi, Ya-juan; Xu, Xiang-bo; Zheng, Xiao-qi; Lu, Yong-long

    2015-01-01

    Tetrabromobisphenol A (TBBPA), hexabromocyclododecane (HBCD) and decabromodiphenyl ether (BDE 209), suspected ubiquitous contaminants, account for the largest volume of brominated flame retardants (BFRs) since penta-BDE and octa-BDE have been phased out globally. In this paper, the growth inhibition and gene transcript levels of antioxidant enzymes (superoxide dismutase (SOD), catalase (CAT)) and the stress-response gene involved in the prevention of oxidative stress (Hsp70) of earthworms (Eisenia fetida) exposed to TBBPA, HBCD and BDE 209 were measured to identify the toxicity effects of selected BFRs on earthworms. The growth of earthworms treated by TBBPA at 200 and 400 mg/kg dw were inhibited at rate of 13.7% and 22.0% respectively, while there was no significant growth inhibition by HBCD and BDE 209. A significant (P<0.01) up-regulation of SOD expression level was observed in earthworms exposed to TBBPA at 50 mg/kg dw (1.77-fold) and to HBCD at 400 mg/kg dw (2.06-fold). The transcript level of Hsp70 gene was significantly up-regulated (P<0.01) when earthworms exposed to TBBPA at concentration of 50-200 mg/kg (2.16-2.19-fold) and HBCD at 400 mg/kg (2.61-fold). No significant variation of CAT gene expression in all the BFRs treatments was observed, neither does all the target gene expression level exposed to BDE 209. Assessed by growth inhibition and the changes at mRNA levels of encoding genes in earthworms, TBBPA showed the greatest toxicity, followed by HBCD and BDE 209, consistent with trends in molecular properties. The results help to understand the molecular mechanism of antioxidant defense. PMID:26117064

  4. Response of the physiological parameters of mango fruit (transpiration, water relations and antioxidant system) to its light and temperature environment.

    PubMed

    Léchaudel, Mathieu; Lopez-Lauri, Félicie; Vidal, Véronique; Sallanon, Huguette; Joas, Jacques

    2013-04-15

    Depending on the position of the fruit in the tree, mango fruit may be exposed to high temperature and intense light conditions that may lead to metabolic and physiological disorders and affect yield and quality. The present study aimed to determine how mango fruit adapted its functioning in terms of fruit water relations, epicarp characteristics and the antioxidant defence system in peel, to environmental conditions. The effect of contrasted temperature and light conditions was evaluated under natural solar radiation and temperature by comparing well-exposed and shaded fruit at three stages of fruit development. The sun-exposed and shaded peels of the two sides of the well-exposed fruit were also compared. Depending on fruit position within the canopy and on the side of a well-exposed fruit, the temperature gradient over a day affected fruit characteristics such as transpiration, as revealed by the water potential gradient as a function of the treatments, and led to a significant decrease in water conductance for well-exposed fruits compared to fruits within the canopy. Changes in cuticle thickness according to fruit position were consistent with those of fruit water conductance. Osmotic potential was also affected by climatic environment and harvest stage. Environmental conditions that induced water stress and greater light exposure, like on the sunny side of well-exposed fruit, increased the hydrogen peroxide, malondialdehyde and total and reduced ascorbate contents, as well as SOD, APX and MDHAR activities, regardless of the maturity stage. The lowest values were measured in the peel of the shaded fruit, that of the shaded side of well-exposed fruit being intermediate. Mango fruits exposed to water-stress-induced conditions during growth adapt their functioning by reducing their transpiration. Moreover, oxidative stress was limited as a consequence of the increase in antioxidant content and enzyme activities. This adaptive response of mango fruit to its

  5. Responses of growth inhibition and antioxidant gene expression in earthworms (Eisenia fetida) exposed to tetrabromobisphenol A, hexabromocyclododecane and decabromodiphenyl ether.

    PubMed

    Shi, Ya-juan; Xu, Xiang-bo; Zheng, Xiao-qi; Lu, Yong-long

    2015-01-01

    Tetrabromobisphenol A (TBBPA), hexabromocyclododecane (HBCD) and decabromodiphenyl ether (BDE 209), suspected ubiquitous contaminants, account for the largest volume of brominated flame retardants (BFRs) since penta-BDE and octa-BDE have been phased out globally. In this paper, the growth inhibition and gene transcript levels of antioxidant enzymes (superoxide dismutase (SOD), catalase (CAT)) and the stress-response gene involved in the prevention of oxidative stress (Hsp70) of earthworms (Eisenia fetida) exposed to TBBPA, HBCD and BDE 209 were measured to identify the toxicity effects of selected BFRs on earthworms. The growth of earthworms treated by TBBPA at 200 and 400 mg/kg dw were inhibited at rate of 13.7% and 22.0% respectively, while there was no significant growth inhibition by HBCD and BDE 209. A significant (P<0.01) up-regulation of SOD expression level was observed in earthworms exposed to TBBPA at 50 mg/kg dw (1.77-fold) and to HBCD at 400 mg/kg dw (2.06-fold). The transcript level of Hsp70 gene was significantly up-regulated (P<0.01) when earthworms exposed to TBBPA at concentration of 50-200 mg/kg (2.16-2.19-fold) and HBCD at 400 mg/kg (2.61-fold). No significant variation of CAT gene expression in all the BFRs treatments was observed, neither does all the target gene expression level exposed to BDE 209. Assessed by growth inhibition and the changes at mRNA levels of encoding genes in earthworms, TBBPA showed the greatest toxicity, followed by HBCD and BDE 209, consistent with trends in molecular properties. The results help to understand the molecular mechanism of antioxidant defense.

  6. [Responses of Pinus koraiensis tree ring cell scale parameters to climate elements in Changbai Mountains].

    PubMed

    Wang, Hui; Shao, Xue-mei; Fang, Xiu-qi; Yin, Zhi-yong; Chen, Li; Zhao, Dong-sheng; Wu, Shao-hong

    2011-10-01

    Based on the tree ring samples of Pinus koraiensis collected from the low altitude areas of Changbai Mountains, seven standard chronologies for tree ring width and cell scale parameters were constructed. Parts of the chronologies were chosen for the correlation analysis with the climate elements in 1959-2007 at Donggang meteorological station, and the changes of the correlations between tree ring indices and climate elements before and after 1988 in which the climate changed abruptly were discussed. In the seven standard chronologies constructed, cell number had the best correlation with tree ring width. Both precipitation and air temperature were the limiting factors for the growth of P. koraiensis, but the chronologies had better correlation with precipitation than with air temperature, mainly manifested in the significant correlation between the chronologies and the precipitation in previous September and current May and June. Comparing with tree ring width, cell size could reveal more climatic information, mainly manifested in the positive correlation between the chronologies and the air temperature in March and the precipitation in May, and the negative correlation between the chronologies and the air temperature in May. After the abrupt change of air temperature in 1988, the responses of cell size to climate elements had some changes, mainly manifested in the decreasing sensitivity to monthly climate elements and the earlier response time.

  7. Mineral elements of subtropical tree seedlings in response to elevated carbon dioxide and nitrogen addition.

    PubMed

    Huang, Wenjuan; Zhou, Guoyi; Liu, Juxiu; Zhang, Deqiang; Liu, Shizhong; Chu, Guowei; Fang, Xiong

    2015-01-01

    Mineral elements in plants have been strongly affected by increased atmospheric carbon dioxide (CO2) concentrations and nitrogen (N) deposition due to human activities. However, such understanding is largely limited to N and phosphorus in grassland. Using open-top chambers, we examined the concentrations of potassium (K), calcium (Ca), magnesium (Mg), aluminum (Al), copper (Cu) and manganese (Mn) in the leaves and roots of the seedlings of five subtropical tree species in response to elevated CO2 (ca. 700 μmol CO2 mol(-1)) and N addition (100 kg N ha(-1) yr(-1)) from 2005 to 2009. These mineral elements in the roots responded more strongly to elevated CO2 and N addition than those in the leaves. Elevated CO2 did not consistently decrease the concentrations of plant mineral elements, with increases in K, Al, Cu and Mn in some tree species. N addition decreased K and had no influence on Cu in the five tree species. Given the shifts in plant mineral elements, Schima superba and Castanopsis hystrix were less responsive to elevated CO2 and N addition alone, respectively. Our results indicate that plant stoichiometry would be altered by increasing CO2 and N deposition, and K would likely become a limiting nutrient under increasing N deposition in subtropics. PMID:25794046

  8. Mechanical Stress Induces Biotic and Abiotic Stress Responses via a Novel cis-Element

    PubMed Central

    Walley, Justin W; Coughlan, Sean; Hudson, Matthew E; Covington, Michael F; Kaspi, Roy; Banu, Gopalan; Harmer, Stacey L; Dehesh, Katayoon

    2007-01-01

    Plants are continuously exposed to a myriad of abiotic and biotic stresses. However, the molecular mechanisms by which these stress signals are perceived and transduced are poorly understood. To begin to identify primary stress signal transduction components, we have focused on genes that respond rapidly (within 5 min) to stress signals. Because it has been hypothesized that detection of physical stress is a mechanism common to mounting a response against a broad range of environmental stresses, we have utilized mechanical wounding as the stress stimulus and performed whole genome microarray analysis of Arabidopsis thaliana leaf tissue. This led to the identification of a number of rapid wound responsive (RWR) genes. Comparison of RWR genes with published abiotic and biotic stress microarray datasets demonstrates a large overlap across a wide range of environmental stresses. Interestingly, RWR genes also exhibit a striking level and pattern of circadian regulation, with induced and repressed genes displaying antiphasic rhythms. Using bioinformatic analysis, we identified a novel motif overrepresented in the promoters of RWR genes, herein designated as the Rapid Stress Response Element (RSRE). We demonstrate in transgenic plants that multimerized RSREs are sufficient to confer a rapid response to both biotic and abiotic stresses in vivo, thereby establishing the functional involvement of this motif in primary transcriptional stress responses. Collectively, our data provide evidence for a novel cis-element that is distributed across the promoters of an array of diverse stress-responsive genes, poised to respond immediately and coordinately to stress signals. This structure suggests that plants may have a transcriptional network resembling the general stress signaling pathway in yeast and that the RSRE element may provide the key to this coordinate regulation. PMID:17953483

  9. An extended finite element formulation for modeling the response of polycrystalline materials to shock loading

    NASA Astrophysics Data System (ADS)

    Robbins, Joshua; Voth, Thomas

    2007-06-01

    The eXtended Finite Element Method (X-FEM) is a finite element based discretization technique developed originally to model dynamic crack propagation [1]. Since that time the method has been used for modeling physics ranging from static mesoscale material failure to dendrite growth. Here we adapt the recent advances of Benson et al. [2] and Belytchko et al. [3] to model shock loading of polycrystalline material. Through several demonstration problems we evaluate the method for modeling the shock response of polycrystalline materials at the mesoscale. Specifically, we use the X-FEM to model grain boundaries. This approach allows us to i) eliminate ad-hoc mixture rules for multi-material elements and ii) avoid explicitly meshing grain boundaries. ([1] N. Moes, J. Dolbow, J and T. Belytschko, 1999,``A finite element method for crack growth without remeshing,'' International Journal for Numerical Methods in Engineering, 46, 131-150. [2] E. Vitali, and D. J. Benson, 2006, ``An extended finite element formulation for contact in multi-material arbitrary Lagrangian-Eulerian calculations,'' International Journal for Numerical Methods in Engineering, 67, 1420-1444. [3] J-H Song, P. M. A. Areias and T. Belytschko, 2006, ``A method for dynamic crack and shear band propagation with phantom nodes,'' International Journal for Numerical Methods in Engineering, 67, 868-893.)

  10. Verification of Advective Bar Elements Implemented in the Aria Thermal Response Code.

    SciTech Connect

    Mills, Brantley

    2016-01-01

    A verification effort was undertaken to evaluate the implementation of the new advective bar capability in the Aria thermal response code. Several approaches to the verification process were taken : a mesh refinement study to demonstrate solution convergence in the fluid and the solid, visually examining the mapping of the advective bar element nodes to the surrounding surfaces, and a comparison of solutions produced using the advective bars for simple geometries with solutions from commercial CFD software . The mesh refinement study has shown solution convergence for simple pipe flow in both temperature and velocity . Guidelines were provided to achieve appropriate meshes between the advective bar elements and the surrounding volume. Simulations of pipe flow using advective bars elements in Aria have been compared to simulations using the commercial CFD software ANSYS Fluent (r) and provided comparable solutions in temperature and velocity supporting proper implementation of the new capability. Verification of Advective Bar Elements iv Acknowledgements A special thanks goes to Dean Dobranich for his guidance and expertise through all stages of this effort . His advice and feedback was instrumental to its completion. Thanks also goes to Sam Subia and Tolu Okusanya for helping to plan many of the verification activities performed in this document. Thank you to Sam, Justin Lamb and Victor Brunini for their assistance in resolving issues encountered with running the advective bar element model. Finally, thanks goes to Dean, Sam, and Adam Hetzler for reviewing the document and providing very valuable comments.

  11. Vortex shedding and morphodynamic response of bed surfaces containing non-erodible roughness elements

    NASA Astrophysics Data System (ADS)

    McKenna Neuman, Cheryl; Sanderson, Robert Steven; Sutton, Stephen

    2013-09-01

    A series of wind tunnel experiments was carried out to investigate particle entrainment from surfaces in which one or more roughness elements were embedded. Thin sand strips were employed to eliminate impact and ejection, and thus isolate entrainment by fluid drag. The pattern of erosion is consistent with the presence of coherent vortices, inclusive of trailing vortices in the wake flow. The shape and orientation of the roughness element strongly influence this pattern. When an upwind supply of saltators is introduced, the majority of particles within the bed are entrained through impact, with the exception of a sand tail to the lee of the roughness element. That is, the effect of coherent structures within the airflow, as related to spatial variation in the fluid drag exerted on the bed surface, is completely overprinted by the saltation cloud and the blocking of particle trajectories by the upwind face of the roughness element. In a repeated set of experiments, the bed was allowed to fully adjust its morphology to the transport system. In this case, particle entrainment did not selectively occur within the zone of wake flow, and by inference the fluid stress across the test surface appeared to be uniform. These experiments support the hypothesis that vortex annihilation occurs on morphodynamically adjusted surfaces. In summary, the system response to the emergence of non-erodible roughness elements on surfaces affected by wind erosion involves a suite of geophysical processes, each of which attains varied levels of dominance within a given morphodynamic domain.

  12. Optimization of Extraction Condition of Bee Pollen Using Response Surface Methodology: Correlation between Anti-Melanogenesis, Antioxidant Activity, and Phenolic Content.

    PubMed

    Kim, Seon Beom; Jo, Yang Hee; Liu, Qing; Ahn, Jong Hoon; Hong, In Pyo; Han, Sang Mi; Hwang, Bang Yeon; Lee, Mi Kyeong

    2015-11-02

    Bee pollen is flower pollen with nectar and salivary substances of bees and rich in essential components. Bee pollen showed antioxidant and tyrosinase inhibitory activity in our assay system. To maximize the antioxidant and tyrosinase inhibitory activity of bee pollen, extraction conditions, such as extraction solvent, extraction time, and extraction temperature, were optimized using response surface methodology. Regression analysis showed a good fit of this model and yielded the second-order polynomial regression for tyrosinase inhibition and antioxidant activity. Among the extraction variables, extraction solvent greatly affected the activity. The optimal condition was determined as EtOAc concentration in MeOH, 69.6%; temperature, 10.0 °C; and extraction time, 24.2 h, and the tyrosinase inhibitory and antioxidant activity under optimal condition were found to be 57.9% and 49.3%, respectively. Further analysis showed the close correlation between activities and phenolic content, which suggested phenolic compounds are active constituents of bee pollen for tyrosinase inhibition and antioxidant activity. Taken together, these results provide useful information about bee pollen as cosmetic therapeutics to reduce oxidative stress and hyperpigmentation.

  13. Application of response surface methodology to optimize pressurized liquid extraction of antioxidant compounds from sage (Salvia officinalis L.), basil (Ocimum basilicum L.) and thyme (Thymus vulgaris L.).

    PubMed

    Hossain, M B; Brunton, N P; Martin-Diana, A B; Barry-Ryan, C

    2010-12-01

    The present study optimized pressurized liquid extraction (PLE) conditions using Dionex ASE® 200, USA to maximize the antioxidant activity [Ferric ion Reducing Antioxidant Power (FRAP)] and total polyphenol content (TP) of the extracts from three spices of Lamiaceae family (sage, basil and thyme). Optimal conditions with regard to extraction temperature (66-129 °C) and solvent concentration (32-88% methanol) were identified using response surface methodology (RSM). For all three spices, results showed that 129 °C was the optimum temperature with regard to antioxidant activity. Optimal methanol concentrations with respect to the antioxidant activity of sage and basil extracts were 58% and 60% respectively. Thyme showed a different trend with regard to methanol concentration and was optimally extracted at 33%. Antioxidant activity yields of the optimal PLE were significantly (p < 0.05) higher than solid/liquid extracts. Predicted models were highly significant (p < 0.05) for both total phenol (TP) and FRAP values in all the spices with high regression coefficients (R(2)) ranging from 0.651 to 0.999.

  14. The effects of resveratrol and selected metabolites on the radiation and antioxidant response

    PubMed Central

    Saito, Keita; DeGraff, William; Sowers, Anastasia L.; Thetford, Angela; Cook, John A.; Krishna, Murali C.; Mitchell, James B.

    2011-01-01

    Excess reactive oxygen species (ROS) generated from ionizing radiation (IR) or endogenous sources like cellular respiration and inflammation produce cytotoxic effects that can lead to carcinogenesis. Resveratrol (RSV), a polyphenol with antioxidant and anticarcinogenic capabilities, has shown promise as a potential radiation modifier. The present study focuses on examining the effects of RSV or RSV metabolites as a radiation modifier in normal tissue. RSV or a RSV metabolite, piceatannol (PIC) did not protect human lung fibroblasts (1522) from the radiation-induced cell killing. Likewise, neither RSV nor PIC afforded protection against lethal total body IR in C3H mice. Additional research has shown protection in cells against hydrogen peroxide when treated with RSV. Therefore, clonogenic survival was measured in 1522 cells with RSV and RSV metabolites. Only the RSV derivative, piceatannol (PIC), showed protection against hydrogen peroxide mediated cytotoxicity; whereas, RSV enhanced hydrogen peroxide sensitivity at a 50 µM concentration; the remaining metabolites evaluated had little to no effect on survival. PIC also showed enhancement to peroxide exposure at a higher concentration (150 µM). A potential mechanism for RSV-induced sensitivity to peroxides could be its ability to block 1522 cells in the S-phase, which is most sensitive to hydrogen peroxide treatment. In addition, both RSV and PIC can be oxidized to phenoxyl radicals and quinones, which may exert cytotoxic effects. These cytotoxic effects were abolished when HBED, a metal chelator, was added. Taken together RSV and many of its metabolic derivatives are not effective as chemical radioprotectors and should not be considered for clinical use. PMID:22024758

  15. Antioxidative and cytoprotective response elicited by molybdenum nanoparticles in human cells.

    PubMed

    Akhtar, Mohd Javed; Ahamed, Maqusood; Alhadlaq, Hisham A; Alshamsan, Aws; Khan, M A Majeed; Alrokayan, Salman A

    2015-11-01

    Nanotechnology based therapeutics can offer an alternative platform in a wide variety of biomedical applications. Here we report novel cytotoxicity preventive potential of molybdenum nanoparticles (Mo NPs) in human breast (MCF-7) and fibrosarcoma (HT-1080) cells compromised with oxidant exposure. Physicochemical properties such as size, crystallinity, purity and band gap (an optical characteristic) of Mo NPs were characterized respectively by field emission transmission electron microscopy (FETEM), X-ray diffraction (XRD), energy dispersive spectrum (EDS) and UV-vis absorption spectroscopy. The average size of crystalline Mo NPs was found to be 35 nm with a band gap of 1.4 eV. Potential cytotoxicity of Mo NPs was evaluated by a battery of cell viability and oxidative stress parameters. Cell viability and oxidative stress data suggested Mo NPs to be reasonably non-cytotoxic. Cytotoxic preventive and GSH restoring potential of Mo NPs was determined against cytotoxicity and oxidative stress induced by H2O2 (and ZnO NPs) in two cells. Mo NPs significantly increased GSH level in MCF-7 and HT-1080 cells, an activity that was comparable to antioxidant N-acetyl cysteine (NAC). GSH level was increased 1.56 times in MCF-7 cells and 1.25 times in HT-1080 cells by 100 μg/ml of Mo NPs relative to control cells in 24 h. End-point data clearly suggest that Mo NPs significantly protected cells against cytotoxicity induced by H2O2 and ZnO (NPs) (p<0.05). Our study warrants further investigation about Mo NPs that could be exploited in myriads of nanotechnology applications.

  16. Sodium nitroprusside-mediated alleviation of iron deficiency and modulation of antioxidant responses in maize plants

    PubMed Central

    Kumar, Praveen; Tewari, Rajesh Kumar; Sharma, Parma Nand

    2010-01-01

    Background and aims Nitric oxide (NO) has been reported to alleviate Fe-deficiency effects, possibly by enhancing the functional Fe status of plants. This study examines changes in tissue Fe status and oxidative metabolism in Fe-deficient maize (Zea mays L.) plants enriched with NO using sodium nitroprusside (SNP) as a source. Methodology Measurements included changes in concentrations of H2O2, non-protein thiols, levels of lipid peroxidation and activities of superoxide dismutase (SOD) and of the Fe-requiring antioxidant haem enzymes catalase, peroxidase and ascorbate peroxidases. Internal NO in Fe-deficient maize plants was manipulated with SNP and the NO scavenger, methylene blue (MB). A key control was treatment with sodium ferrocyanide (SF), a non-NO-supplying analogue of SNP. Principal results SNP but not SF caused re-greening of leaves in Fe-deficient maize plants over 10–20 days, increased in vivo NO content, raised chlorophyll and carotenoid concentrations, promoted growth in dry weight, increased the activities of H2O2-scavenging haem enzymes and enhanced lipid peroxidation, while decreasing SOD activity and H2O2 concentrations. The NO scavenger, MB, blocked the effects of the SNP. Although SNP and SF each donated Fe and increased active Fe, only SNP increased leaf chlorophyll. Conclusions NO plays a role in Fe nutrition, independently of its effect on total or active Fe status. The most probable mechanism of NO involvement is to increase the intracellular availability of Fe by means of modulating redox. This is likely to be achieved by enhancing the chemical reduction of foliar Fe(III) to Fe(II). PMID:22476060

  17. Simulation of the ultrasonic array response from real branched cracks using an efficient finite element method

    SciTech Connect

    Felice, Maria V.; Velichko, Alexander; Wilcox, Paul D.; Barden, Tim J.; Dunhill, Tony K.

    2014-02-18

    A hybrid model to simulate the ultrasonic array response from stress corrosion cracks is presented. These cracks are branched and difficult to detect so the model is required to enable optimization of an array design. An efficient frequency-domain finite element method is described and selected to simulate the ultrasonic scattering. Experimental validation results are presented, followed by an example of the simulated ultrasonic array response from a real stress corrosion crack whose geometry is obtained from an X-ray Computed Tomography image. A simulation-assisted array design methodology, which includes the model and use of real crack geometries, is proposed.

  18. Isolation of transcription factors binding auxin response elements using a yeast one-hybrid system.

    PubMed

    Qi, Mei; Huang, Meijuan; Chen, Fan

    2002-04-01

    Plant hormones play an important role during higher plant embryogenesis. Auxin is central to the development of vascular tissues, formation of lateral and adventitious roots, control of apical dominance, and tropic responses. Auxin response element (AuxRE), present in the promoters of many auxin-induced genes, can confer auxin responsiveness. Using carrot somatic embryo under specific developmental phase, a cDNA expression library was constructed. Several plasmids were recombined containing the tetramer of AuxRE as a bait. After screening by a yeast one-hy-brid system, one positive clone was confirmed and characterized. Electrophoretic mobility shift assay showed that AxRF1 protein expressed in yeast cell could bind AuxRE in vitro. It suggests that AxRF1 participates in regulation of the expression of auxin responsive gene during carrot somatic embryogenesis. PMID:18763077

  19. Nuclear receptor coactivators facilitate vitamin D receptor homodimer action on direct repeat hormone response elements.

    PubMed

    Takeshita, A; Ozawa, Y; Chin, W W

    2000-03-01

    Vitamin D receptor (VDR) is a ligand-dependent transcription factor that regulates target gene expression. Although VDR forms stable heterodimer complex with retinoid X receptors (RXRs) on vitamin D-response elements (VDREs), it is still not clear whether VDR/RXR heterodimers are the only VDR complexes responsible for vitamin D-mediated gene transcription. In this report, we analyzed the effect of nuclear receptor coactivators (SRC-1 and TRAM-1) on VDR homodimer and VDR/RXR heterodimer formation by electrophoretic mobility shift assay. We found that VDR forms stable homodimers after interaction with the coactivators on a VDRE (DR+3). Of particular note, DR+4 and DR+5 hormone-response elements (HREs) may also support such interactions. Cotransfection experiments revealed further that the coactivators enhance ligand-induced VDR transcription on these elements. Our studies suggest the important role of VDR homodimers, in addition to VDR/RXR heterodimers, in vitamin D-induced transactivation. Thus, specific coactivator-VDR interactions on HREs may determine target gene transactivation.

  20. A Novel Peroxisome Proliferator Response Element Modulates Hepatic Low Density Lipoprotein Receptor Gene Transcription in Response to PPARδ Activation

    PubMed Central

    Shende, Vikram R.; Singh, Amar Bahadur; Liu, Jingwen

    2016-01-01

    The hepatic expression of LDLR gene is regulated primarily at the transcriptional level by a sterol-regulatory element (SRE) in its proximal promoter region which is the site of action of SRE-binding protein 2 (SREBP2). However whether additional cis-regulatory elements contribute to LDLR transcription has not been fully explored. We investigated the function of a putative PPAR-response element (PPRE) sequence motif located at −768 to −752 bases upstream of the transcription start site of human LDLR gene in response to PPARδ activation. Promoter luciferase reporter analyses showed that treating HepG2 cells with PPARδ agonist L165041 markedly increased the activity of a full-length LDLR promoter construct (pLDLR-1192) without any effects on the shorter promoter reporter pLDLR-234 that contains only the core regulatory elements SRE-1 and SP1 sites. Importantly, mutation of the PPRE sequence greatly attenuated the induction of the full-length LDLR promoter activity by L165041 without affecting rosuvastatin mediated transactivation. Electrophoretic mobility shift and chromatin immunoprecipitation assays further confirmed the binding of PPARδ to the LDLR-PPRE site. Treating HepG2 cells with L165041 elevated the mRNA and protein expressions of LDLR without affecting the LDLR mRNA decay rate. The induction of LDLR expression by PPARδ agonist was further observed in liver tissue of mice and hamsters treated with L165041. Altogether, our studies identify a novel PPRE-mediated regulatory mechanism for LDLR transcription and suggest that combined treatment of statin with PPARδ agonists may have advantageous effects on LDLR expression. PMID:26443862

  1. Activation of Heat Shock and Antioxidant Responses by the Natural Product Celastrol: Transcriptional Signatures of a Thiol-targeted Molecule

    PubMed Central

    Trott, Amy; West, James D.; Klaić, Lada; Westerheide, Sandy D.; Silverman, Richard B.; Morimoto, Richard I.

    2008-01-01

    Stress response pathways allow cells to sense and respond to environmental changes and adverse pathophysiological states. Pharmacological modulation of cellular stress pathways has implications in the treatment of human diseases, including neurodegenerative disorders, cardiovascular disease, and cancer. The quinone methide triterpene celastrol, derived from a traditional Chinese medicinal herb, has numerous pharmacological properties, and it is a potent activator of the mammalian heat shock transcription factor HSF1. However, its mode of action and spectrum of cellular targets are poorly understood. We show here that celastrol activates Hsf1 in Saccharomyces cerevisiae at a similar effective concentration seen in mammalian cells. Transcriptional profiling revealed that celastrol treatment induces a battery of oxidant defense genes in addition to heat shock genes. Celastrol activated the yeast Yap1 oxidant defense transcription factor via the carboxy-terminal redox center that responds to electrophilic compounds. Antioxidant response genes were likewise induced in mammalian cells, demonstrating that the activation of two major cell stress pathways by celastrol is conserved. We report that celastrol's biological effects, including inhibition of glucocorticoid receptor activity, can be blocked by the addition of excess free thiol, suggesting a chemical mechanism for biological activity based on modification of key reactive thiols by this natural product. PMID:18199679

  2. A comparative study on antioxidant status combined with integrated biomarker response in Carassius auratus fish exposed to nine phthalates.

    PubMed

    Qu, Ruijuan; Feng, Mingbao; Sun, Ping; Wang, Zunyao

    2015-09-01

    Laboratory experiments were performed to determine the antioxidant responses to nine phthalates (PAEs) in the liver of the goldfish Carassius auratus. The fish were injected with 10 mg/kg body weight of each PAE for 1 day and 4, 8, and 15 days. The potential biotoxicity of the PAEs were examined using the antioxidase and lipid peroxide indices. We determined that the superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx), and malondialdehyde (MDA) levels displayed different trends following prolonged treatment, suggesting that metabolism generated either less toxic or more active substances. Based on the intensity of enzymes inhibition, MDA content, and the calculated integrated biomarker response (IBR), the toxicity order was determined as follows: dibutyl phthalate (DBP) > diethyl phthalate (DEP) > diisodecyl phthalate (DIDP) > diphenyl phthalate (DPP) > butyl benzyl phthalate (BBP) > diallyl phthalate (DAP) > dicyclohexyl phthalate (DCHP) > dimethyl phthalate (DMP) > di(2-ethylhexyl) phthalate (DEHP). In particular, DBP, which exhibited significant inhibition of enzyme activity and the greatest decrease in MDA content, may be a highly toxic contaminant. Furthermore, our results suggest that the IBR may be a general marker of pollution.

  3. Responses of antioxidant systems after exposition to rare earths and their role in chilling stress in common duckweed (Lemna minor L.): a defensive weapon or a boomerang?

    PubMed

    Ippolito, M P; Fasciano, C; d'Aquino, L; Morgana, M; Tommasi, F

    2010-01-01

    Extensive agriculture application of rare earth elements (REEs) in Far East countries might cause spreading of these metals in aquatic and terrestrial ecosystems, thus inducing a growing concern about their environmental impact. In this work the effects of a mix of different REE nitrate (RE) and of lanthanum nitrate (LA) on catalase and antioxidant systems involved in the ascorbate-glutathione cycle were investigated in common duckweed Lemna minor L. The results indicated that L. minor shows an overall good tolerance to the presence of REEs in the media. Treatments at concentrations up to 5 mM RE and 5 mM LA did not cause either visible symptoms on plants or significant effects on reactive oxygen species (ROS) production, chlorophyll content, and lipid peroxidation. Toxic effects were observed after 5 days of exposition to 10 mM RE and 10 mM LA. A remarkable increase in glutathione content as well as in enzymatic antioxidants was observed before the appearance of the stress symptoms in treated plants. Duckweed plants pretreated with RE and LA were also exposed to chilling stress to verify whether antioxidants variations induced by RE and LA improve plant resistance to the chilling stress. In pretreated plants, a decrease in ascorbate and glutathione redox state and in chlorophyll content and an increase in lipid peroxidation and ROS production levels were observed. The use of antioxidant levels as a stress marker for monitoring REE toxicity in aquatic ecosystems by means of common duckweed is discussed. PMID:19504227

  4. Equivalent Dynamic Stiffness Mapping technique for identifying nonlinear structural elements from frequency response functions

    NASA Astrophysics Data System (ADS)

    Wang, X.; Zheng, G. T.

    2016-02-01

    A simple and general Equivalent Dynamic Stiffness Mapping technique is proposed for identifying the parameters or the mathematical model of a nonlinear structural element with steady-state primary harmonic frequency response functions (FRFs). The Equivalent Dynamic Stiffness is defined as the complex ratio between the internal force and the displacement response of unknown element. Obtained with the test data of responses' frequencies and amplitudes, the real and imaginary part of Equivalent Dynamic Stiffness are plotted as discrete points in a three dimensional space over the displacement amplitude and the frequency, which are called the real and the imaginary Equivalent Dynamic Stiffness map, respectively. These points will form a repeatable surface as the Equivalent Dynamic stiffness is only a function of the corresponding data as derived in the paper. The mathematical model of the unknown element can then be obtained by surface-fitting these points with special functions selected by priori knowledge of the nonlinear type or with ordinary polynomials if the type of nonlinearity is not pre-known. An important merit of this technique is its capability of dealing with strong nonlinearities owning complicated frequency response behaviors such as jumps and breaks in resonance curves. In addition, this technique could also greatly simplify the test procedure. Besides there is no need to pre-identify the underlying linear parameters, the method uses the measured data of excitation forces and responses without requiring a strict control of the excitation force during the test. The proposed technique is demonstrated and validated with four classical single-degree-of-freedom (SDOF) numerical examples and one experimental example. An application of this technique for identification of nonlinearity from multiple-degree-of-freedom (MDOF) systems is also illustrated.

  5. Trace element concentrations and bioindicator responses in tree swallows from northwestern Minnesota

    USGS Publications Warehouse

    Custer, Christine M.; Custer, T.W.; Warburton, D.; Hoffman, D.J.; Bickham, J.W.; Matson, C.W.

    2006-01-01

    Abstract Extremely high concentrations of cadmium (3.5 ug/g dry wgt.) and elevated concentrations of chromium (>10 ug/g dry wgt.) and mercury (1.6 ug/g dry wgt.) were reported in waterbird tissues at Agassiz National Wildlife Refuge in northwestern Minnesota in 1994. Tree swallows (Tachycineta bicolor) were studied during 1998-2001 at three drainages into the Refuge, two pools on the Refuge, and at a nearby reference location to document whether high levels of contaminants were still present, and if so to quantify the source and severity of the contamination. Trace elements were measured in tree swallow eggs, livers, and diet. Reproductive success and bioindicator responses were monitored. In 2000, water was drawn down on Agassiz Pool, one of the main pools on the Refuge. This presented an opportunity to evaluate the response of trace element concentrations in the diet and tissues of tree swallows after reflooding. High concentrations of trace elements were not detected in swallow tissues, nor were there differences among locations. Less than 20% of swallow samples had detectable concentrations of cadmium or chromium. Mercury concentrations were low and averaged <0.25 ug/g dry wgt. in swallow tissues. Trace elements, including mercury, did not increase in tree swallows following the 2000 drawdown at Agassiz Pool. Hatching success and survival of nestlings to 12 days-of-age for tree swallows on the Refuge were similar to the national average and consistent with background trace element concentrations. Bioindicator measurements were within the normal ranges as well.

  6. The importance of antioxidants which play the role in cellular response against oxidative/nitrosative stress: current state.

    PubMed

    Kurutas, Ergul Belge

    2016-01-01

    Remarkable interest has risen in the idea that oxidative/nitrosative stress is mediated in the etiology of numerous human diseases. Oxidative/Nitrosative stress is the result of an disequilibrium in oxidant/antioxidant which reveals from continuous increase of Reactive Oxygen and Reactive Nitrogen Species production. The aim of this review is to emphasize with current information the importance of antioxidants which play the role in cellular responce against oxidative/nitrosative stress, which would be helpful in enhancing the knowledge of any biochemist, pathophysiologist, or medical personnel regarding this important issue. Products of lipid peroxidation have commonly been used as biomarkers of oxidative/nitrosative stress damage. Lipid peroxidation generates a variety of relatively stable decomposition end products, mainly α, β-unsaturated reactive aldehydes, such as malondialdehyde, 4-hydroxy-2-nonenal, 2-propenal (acrolein) and isoprostanes, which can be measured in plasma and urine as an indirect index of oxidative/nitrosative stress. Antioxidants are exogenous or endogenous molecules that mitigate any form of oxidative/nitrosative stress or its consequences. They may act from directly scavenging free radicals to increasing antioxidative defences. Antioxidant deficiencies can develop as a result of decreased antioxidant intake, synthesis of endogenous enzymes or increased antioxidant utilization. Antioxidant supplementation has become an increasingly popular practice to maintain optimal body function. However, antoxidants exhibit pro-oxidant activity depending on the specific set of conditions. Of particular importance are their dosage and redox conditions in the cell.

  7. The importance of antioxidants which play the role in cellular response against oxidative/nitrosative stress: current state.

    PubMed

    Kurutas, Ergul Belge

    2016-01-01

    Remarkable interest has risen in the idea that oxidative/nitrosative stress is mediated in the etiology of numerous human diseases. Oxidative/Nitrosative stress is the result of an disequilibrium in oxidant/antioxidant which reveals from continuous increase of Reactive Oxygen and Reactive Nitrogen Species production. The aim of this review is to emphasize with current information the importance of antioxidants which play the role in cellular responce against oxidative/nitrosative stress, which would be helpful in enhancing the knowledge of any biochemist, pathophysiologist, or medical personnel regarding this important issue. Products of lipid peroxidation have commonly been used as biomarkers of oxidative/nitrosative stress damage. Lipid peroxidation generates a variety of relatively stable decomposition end products, mainly α, β-unsaturated reactive aldehydes, such as malondialdehyde, 4-hydroxy-2-nonenal, 2-propenal (acrolein) and isoprostanes, which can be measured in plasma and urine as an indirect index of oxidative/nitrosative stress. Antioxidants are exogenous or endogenous molecules that mitigate any form of oxidative/nitrosative stress or its consequences. They may act from directly scavenging free radicals to increasing antioxidative defences. Antioxidant deficiencies can develop as a result of decreased antioxidant intake, synthesis of endogenous enzymes or increased antioxidant utilization. Antioxidant supplementation has become an increasingly popular practice to maintain optimal body function. However, antoxidants exhibit pro-oxidant activity depending on the specific set of conditions. Of particular importance are their dosage and redox conditions in the cell. PMID:27456681

  8. Transient Response of Rotor on Rolling-Element Bearings with Clearance

    NASA Technical Reports Server (NTRS)

    Fleming, David P.; Murphy, Brian T.; Sawicki, Jerzy T.; Poplawski, J. V.

    2006-01-01

    Internal clearance in rolling element bearings is usually present to allow for radial and axial growth of the rotor-bearing system and to accommodate bearing fit-up. The presence of this clearance also introduces a "dead band" into the load-deflection behavior of the bearing. Previous studies demonstrated that the presence of dead band clearance might have a significant effect on synchronous rotor response. In this work, the authors investigate transient response of a rotor supported on rolling element bearings with internal clearance. In addition, the stiffness of the bearings varies nonlinearly with bearing deflection and with speed. Bearing properties were accurately calculated with a state of the art rolling bearing analysis code. The subsequent rotordynamics analysis shows that for rapid acceleration rates the maximum response amplitude may be less than predicted by steady-state analysis. The presence of clearance may shift the critical speed location to lower speed values. The rotor vibration response exhibits subharmonic components which are more prominent with bearing clearance.

  9. Validation of an interferon stimulatory response element reporter gene assay for quantifying type I interferons.

    PubMed

    McCoski, S R; Xie, M; Hall, E B; Mercadante, P M; Spencer, T E; Lonergan, P; Ealy, A D

    2014-04-01

    The goal of this work was to develop a virus-free, cell-based interferon (IFN) bioassay and determine the utility of this assay on biological samples that contained IFN-τ, the trophoblast-secreted maternal recognition of pregnancy factor in ruminants. Madin-Darby bovine kidney cells were transduced with lentiviral particles that contained a firefly luciferase reporter construct driven by an IFN stimulatory response element (ISRE). Stably transduced cells were selected with the use of puromycin resistance. A linear, dose-responsive response was detected with human IFN-α and ovine IFN-τ. Interferon activity was detected in conditioned media from bovine trophoblast cells and uterine flushes collected from sheep and cattle. Activity also was detected in media collected after individual or small group culture of in vitro-produced bovine blastocysts at day 8 to 10 after fertilization. In summary, this IFN stimulatory response element-reporter assay may be used as an alternative to virus-dependent, cytopathic assays. It contains a similar sensitivity to IFNs and can be completed in a shorter time than cytopathic assays and does not require heightened biosafety conditions after cell transduction.

  10. Novel regulation of cardiac force-frequency relation by CREM (cAMP response element modulator).

    PubMed

    Isoda, Takayoshi; Paolocci, Nazareno; Haghighi, Kobra; Wang, Congrong; Wang, Yibin; Georgakopoulos, Dimitrios; Servillo, Giuseppe; Della Fazia, Maria Agnese; Kranias, Evangelia G; Depaoli-Roach, Anna A; Sassone-Corsi, Paolo; Kass, David A

    2003-02-01

    The cAMP response element modulator (CREM) plays pivotal roles in the hypothalamic-pituitary-gonadal axis. CREM mRNA is robustly expressed in human myocardium, and identified isoforms may suppress cAMP response element-mediated transcription. However, little is known about the physiological importance of CREM in intact hearts remains unknown. We studied CREM-null mice and age-matched control littermates by in vivo pressure-volume loops to analyze basal and reserve cardiac function. Basal systolic and diastolic function, echocardiographic morphology, and myocardial histology were normal in CREM-null animals. However functional reserve with increasing heart rate was markedly depressed, with less contractile augmentation (+22+/-9% CREM-/- vs.+62+/-11% controls, P<0.05) and relaxation shortening (5+/-5% CREM-/- vs. -18+/-3% controls; P<0.05) at faster rates. In contrast, isoproterenol dose-responses were similar, suggesting normal beta-adrenergic receptor-coupled signaling. Gene expression of calcium handling proteins (SERCA, phospholamban) and stress-response genes (e.g., alpha-skeletal actin, beta-myosin heavy chain, natriuretic peptides) were similar between groups. However, total and serine-phosphorylated phospholamban protein declined -38 and -64% respectively, and protein phosphatase-1 (PP1) activity increased 44% without increased protein levels (all P<0.01) in CREM-/- vs. controls. These results demonstrate novel involvement of CREM in regulation of PP1 activity and of PLB, likely resulting in a potent frequency-dependent influence on cardiac function.

  11. Identification of a cyclic-AMP-responsive element within the rat somatostatin gene.

    PubMed Central

    Montminy, M R; Sevarino, K A; Wagner, J A; Mandel, G; Goodman, R H

    1986-01-01

    We have examined the regulation of somatostatin gene expression by cAMP in PC12 rat pheochromocytoma cells transfected with the rat somatostatin gene. Forskolin at 10 microM caused a 4-fold increase in somatostatin mRNA levels within 4 hr of treatment in stably transfected cells. Chimeric genes containing the somatostatin gene promoter fused to the bacterial reporter gene encoding chloramphenicol acetyltransferase were also induced by cAMP in PC12 cells. To delineate the sequences required for response to cAMP, we constructed a series of promoter deletion mutants. Our studies defined a region between 60 and 29 base pairs upstream from the transcriptional initiation site that conferred cAMP responsiveness when placed adjacent to the simian virus 40 promoter. Within the cAMP-responsive element of the somatostatin gene, we observed an 8-base palindrome, 5'-TGACGTCA-3', which is highly conserved in many other genes whose expression is regulated by cAMP. cAMP responsiveness was greatly reduced when the somatostatin fusion genes were transfected into the mutant PC12 line A126-1B2, which is deficient in cAMP-dependent protein kinase 2. Our studies indicate that transcriptional regulation of the somatostatin gene by cAMP requires protein kinase 2 activity and may depend upon a highly conserved promoter element. Images PMID:2875459

  12. Effects of in ovo injection with selenium on immune and antioxidant responses during experimental necrotic enteritis in broiler chickens.

    PubMed

    Lee, S H; Lillehoj, H S; Jang, S I; Jeong, M S; Xu, S Z; Kim, J B; Park, H J; Kim, H R; Lillehoj, E P; Bravo, D M

    2014-05-01

    This study was conducted to investigate the effects of in ovo injection of Se on modulating the immune system and antioxidant responses in broiler chickens with experimental necrotic enteritis. Broiler eggs were injected at 18 d of embryo age with either 100 μL of PBS alone or sodium selenite (Na2SeO3) in PBS, providing 0 (SS0), 10 (SS10), or 20 (SS20) μg of Se/egg. At 14 d posthatch, PBS-treated and uninfected chickens were kept as the control group, whereas the remaining chickens were orally infected with 1.0 × 10(4) sporulated oocysts of Eimeria maxima (SS0, SS10, SS20). At 18 d posthatch, E. maxima-infected chickens were orally infected with 1.0 × 10(9) cfu of Clostridium perfringens. Infected control SS0 group showed significantly decreased BW compared with the uninfected control. However, SS20 group showed significantly increased BW compared with the infected control SS0 group, whereas the BW were similar among uninfected control and infected SS10 and SS20 groups. The SS10 group showed significantly lower intestinal lesions compared with the SS0 group, and oocyst production was decreased in both SS10 and SS20 groups. Serum malondialdehyde level and catalase activity were also decreased in both SS10 and SS20 groups, whereas the superoxide dismutase level was significantly lower in the SS10 group compared with the SS0 group. The SS20 group showed significantly higher levels of transcripts for IL-1β and IL-6 in intestine, and SS10 and SS20 groups had higher levels of transcripts for IL-8 and inducible nitric oxide synthase expression and decreased glutathione peroxidase 7 mRNA levels compared with the SS0 group. The SS10 and SS20 groups also showed increased serum antibody levels to C. perfringens α-toxin and NetB toxin compared with the SS0 group. These collective results suggest that the injection of Se into the amniotic cavity of developing eggs may be beneficial for enhancing immune and antioxidant responses in the hatched chickens exposed to the

  13. Hypoxia depresses CYP1A induction and enhances DNA damage, but has minimal effects on antioxidant responses in sheepshead minnow (Cyprinodon variegatus) larvae exposed to dispersed crude oil.

    PubMed

    Dasgupta, Subham; DiGiulio, Richard T; Drollette, Brian D; L Plata, Desire; Brownawell, Bruce J; McElroy, Anne E

    2016-08-01

    The growing incidence of hypoxic regions in coastal areas receiving high volumes of anthropogenic discharges requires more focused risk assessment of multiple stressors. One area needing further study is the combined effect of hypoxia and oil exposure. This study examined the short-term sublethal effects of co-exposure to hypoxia and water accommodated fractions (WAF) and chemically enhanced WAFs (CEWAFs) of Southern Louisiana Crude oil on detoxification, antioxidant defenses and genotoxicity in early life stage sheepshead minnow (Cyprinodon variegatus). CYP1A induction (evaluated by measuring EROD activity), activity of a number of key antioxidant enzymes (GST, GR, GPx, SOD, CAT, and GCL), levels of antioxidants (tGSH, GSH, and GSSG), evidence of lipid peroxidation (evaluated using the TBARS assay), and DNA damage (evaluated using the comet assay) provided a broad assessment of responses. Contaminant detoxification pathways induced by oil exposure were inhibited by co-exposure to hypoxia, indicating a maladaptive response. The interactive effects of oil and hypoxia on antioxidant defenses were mixed, but generally indicated less pronounced alterations, with significant increases in lipid peroxidation not observed. Hypoxia significantly enhanced DNA damage induced by oil exposure indicating the potential for significant deleterious effects post exposure. This study demonstrates the importance of considering hypoxia as an enhanced risk factor in assessing the effects of contaminants in areas where seasonal hypoxia may be prevalent. PMID:27315012

  14. Antenatal Antioxidant Prevents Nicotine-Mediated Hypertensive Response in Rat Adult Offspring.

    PubMed

    Xiao, DaLiao; Huang, Xiaohui; Li, Yong; Dasgupta, Chiranjib; Wang, Lei; Zhang, Lubo

    2015-09-01

    Previous studies have demonstrated that perinatal nicotine exposure increased blood pressure (BP) in adult offspring. However, the underlying mechanisms were unclear. The present study tested the hypothesis that perinatal nicotine-induced programming of hypertensive response is mediated by enhanced reactive oxygen species (ROS) in the vasculature. Nicotine was administered to pregnant rats via subcutaneous osmotic mini-pumps from Day 4 of gestation to Day 10 after birth, in the absence or presence of the ROS inhibitor N-acetyl-cysteine (NAC) in the drinking water. Experiments were conducted in 8-mo-old male offspring. Perinatal nicotine treatment resulted in a significant increase in arterial ROS production in offspring, which was abrogated by NAC. Angiotensin II (Ang II)-induced BP responses were significantly higher in nicotine-treated group than in saline-treated control group, and NAC treatment blocked the nicotine-induced increase in BP response. Consistent with that, the nicotine treatment significantly increased both Ang II-induced and phorbol [12, 13]-dibutyrate (PDBu, a Prkc activator)-induced arterial contractions in adult offspring, which were blocked by NAC treatment. In addition, perinatal nicotine treatment significantly attenuated acetylcholine-induced arterial relaxation in offspring, which was also inhibited by NAC treatment. Results demonstrate that inhibition of ROS blocks the nicotine-induced increase in arterial reactivity and BP response to vasoconstrictors in adult offspring, suggesting a key role for increased oxidative stress in nicotine-induced developmental programming of hypertensive phenotype in male offspring.

  15. Analysis of Resonance Response Performance of C-Band Antenna Using Parasitic Element

    PubMed Central

    Islam, M. T.; Misran, N.; Mandeep, J. S.

    2014-01-01

    Analysis of the resonance response improvement of a planar C-band (4–8 GHz) antenna is proposed using parasitic element method. This parasitic element based method is validated for change in the active and parasitic antenna elements. A novel dual-band antenna for C-band application covering 5.7 GHz and 7.6 GHz is designed and fabricated. The antenna is composed of circular parasitic element with unequal microstrip lines at both sides and a rectangular partial ground plane. A fractional bandwidth of 13.5% has been achieved from 5.5 GHz to 6.3 GHz (WLAN band) for the lower band. The upper band covers from 7.1 GHz to 8 GHz with a fractional bandwidth of 12%. A gain of 6.4 dBi is achieved at the lower frequency and 4 dBi is achieved at the upper frequency. The VSWR of the antenna is less than 2 at the resonance frequency. PMID:24895643

  16. Analysis of resonance response performance of C-band antenna using parasitic element.

    PubMed

    Zaman, M R; Islam, M T; Misran, N; Mandeep, J S

    2014-01-01

    Analysis of the resonance response improvement of a planar C-band (4-8 GHz) antenna is proposed using parasitic element method. This parasitic element based method is validated for change in the active and parasitic antenna elements. A novel dual-band antenna for C-band application covering 5.7 GHz and 7.6 GHz is designed and fabricated. The antenna is composed of circular parasitic element with unequal microstrip lines at both sides and a rectangular partial ground plane. A fractional bandwidth of 13.5% has been achieved from 5.5 GHz to 6.3 GHz (WLAN band) for the lower band. The upper band covers from 7.1 GHz to 8 GHz with a fractional bandwidth of 12%. A gain of 6.4 dBi is achieved at the lower frequency and 4 dBi is achieved at the upper frequency. The VSWR of the antenna is less than 2 at the resonance frequency. PMID:24895643

  17. Finite-element/progressive-lattice-sampling response surface methodology and application to benchmark probability quantification problems

    SciTech Connect

    Romero, V.J.; Bankston, S.D.

    1998-03-01

    Optimal response surface construction is being investigated as part of Sandia discretionary (LDRD) research into Analytic Nondeterministic Methods. The goal is to achieve an adequate representation of system behavior over the relevant parameter space of a problem with a minimum of computational and user effort. This is important in global optimization and in estimation of system probabilistic response, which are both made more viable by replacing large complex computer models with fast-running accurate and noiseless approximations. A Finite Element/Lattice Sampling (FE/LS) methodology for constructing progressively refined finite element response surfaces that reuse previous generations of samples is described here. Similar finite element implementations can be extended to N-dimensional problems and/or random fields and applied to other types of structured sampling paradigms, such as classical experimental design and Gauss, Lobatto, and Patterson sampling. Here the FE/LS model is applied in a ``decoupled`` Monte Carlo analysis of two sets of probability quantification test problems. The analytic test problems, spanning a large range of probabilities and very demanding failure region geometries, constitute a good testbed for comparing the performance of various nondeterministic analysis methods. In results here, FE/LS decoupled Monte Carlo analysis required orders of magnitude less computer time than direct Monte Carlo analysis, with no appreciable loss of accuracy. Thus, when arriving at probabilities or distributions by Monte Carlo, it appears to be more efficient to expend computer-model function evaluations on building a FE/LS response surface than to expend them in direct Monte Carlo sampling.

  18. Two-Dimensional Finite Element Ablative Thermal Response Analysis of an Arcjet Stagnation Test

    NASA Technical Reports Server (NTRS)

    Dec, John A.; Laub, Bernard; Braun, Robert D.

    2011-01-01

    The finite element ablation and thermal response (FEAtR, hence forth called FEAR) design and analysis program simulates the one, two, or three-dimensional ablation, internal heat conduction, thermal decomposition, and pyrolysis gas flow of thermal protection system materials. As part of a code validation study, two-dimensional axisymmetric results from FEAR are compared to thermal response data obtained from an arc-jet stagnation test in this paper. The results from FEAR are also compared to the two-dimensional axisymmetric computations from the two-dimensional implicit thermal response and ablation program under the same arcjet conditions. The ablating material being used in this arcjet test is phenolic impregnated carbon ablator with an LI-2200 insulator as backup material. The test is performed at the NASA, Ames Research Center Interaction Heating Facility. Spatially distributed computational fluid dynamics solutions for the flow field around the test article are used for the surface boundary conditions.

  19. Effect of vitamin and trace-element supplementation on immune responses and infection in elderly subjects.

    PubMed

    Chandra, R K

    1992-11-01

    Ageing is associated with impaired immune responses and increased infection-related morbidity. This study assessed the effect of physiological amounts of vitamins and trace elements on immunocompetence and occurrence of infection-related illness. 96 independently living, healthy elderly individuals were randomly assigned to receive nutrient supplementation or placebo. Nutrient status and immunological variables were assessed at baseline and at 12 months, and the frequency of illness due to infection was ascertained. Subjects in the supplement group had higher numbers of certain T-cell subsets and natural killer cells, enhanced proliferation response to mitogen, increased interleukin-2 production, and higher antibody response and natural killer cell activity. These subjects were less likely than those in the placebo group to have illness due to infections (mean [SD] 23 [5] vs 48 [7] days per year, p = 0.002). Supplementation with a modest physiological amount of micronutrients improves immunity and decreases the risk of infection in old age.

  20. Liver antioxidant and plasma immune responses in juvenile golden grey mullet (Liza aurata) exposed to dispersed crude oil.

    PubMed

    Milinkovitch, Thomas; Ndiaye, Awa; Sanchez, Wilfried; Le Floch, Stéphane; Thomas-Guyon, Hélène

    2011-01-17

    Dispersants are often used after oil spills. To evaluate the environmental cost of this operation in nearshore habitats, the experimental approach conducted in this study exposed juvenile golden grey mullets (Liza aurata) for 48 h to chemically dispersed oil (simulating, in vivo, dispersant application), to dispersant alone in seawater (as an internal control of chemically dispersed oil), to mechanically dispersed oil (simulating, in vivo, natural dispersion), to the water-soluble fraction of oil (simulating, in vivo, an oil slick confinement response technique) and to seawater alone (control condition). Biomarkers such as fluorescence of biliary polycyclic aromatic hydrocarbon (PAH) metabolites, total glutathione liver content, EROD (7-ethoxy-resorufin-O-deethylase) activity, liver antioxidant enzyme activities, liver lipid peroxidation and an innate immune parameter (haemolytic activity of the alternative complement pathway) were measured to assess the toxicity of dispersant application. Significant responses of PAH metabolites and total glutathione content of liver to chemically dispersed oil were found, when compared to water-soluble fraction of oil. As was suggested in other studies, these results highlight that priority must be given to oil slick confinement instead of dispersant application. However, since the same patterns of biomarker responses were observed for both chemically and mechanically dispersed oil, the results also suggest that dispersant application is no more toxic than the natural dispersion occurring in nearshore areas (due to, e.g. waves). The results of this study must, nevertheless, be interpreted cautiously since other components of nearshore habitats must be considered to establish a framework for dispersant use in nearshore areas. PMID:20970861

  1. Effects of rare earth elements and REE-binding proteins on physiological responses in plants.

    PubMed

    Liu, Dongwu; Wang, Xue; Chen, Zhiwei

    2012-02-01

    Rare earth elements (REEs), which include 17 elements in the periodic table, share chemical properties related to a similar external electronic configuration. REEs enriched fertilizers have been used in China since the 1980s. REEs could enter the cell and cell organelles, influence plant growth, and mainly be bound with the biological macromolecules. REE-binding proteins have been found in some plants. In addition, the chlorophyll activities and photosynthetic rate can be regulated by REEs. REEs could promote the protective function of cell membrane and enhance the plant resistance capability to stress produced by environmental factors, and affect the plant physiological mechanism by regulating the Ca²⁺ level in the plant cells. The focus of present review is to describe how REEs and REE-binding proteins participate in the physiological responses in plants.

  2. Identification of peroxisome-proliferator responsive element in the mouse HSL gene

    SciTech Connect

    Yajima, Hiroaki . E-mail: hyajima@kirin.co.jp; Kobayashi, Yumie; Kanaya, Tomoka; Horino, Yoko

    2007-01-12

    Hormone-sensitive lipase (HSL) catalyzes the rate-limiting step of lipolysis in adipose tissue. Several studies suggest that protein phosphorylation regulates the HSL enzymatic activity. On the other hand, the precise mechanism of the transcriptional regulation of the HSL gene remains to be elucidated. Here, we identified a functional peroxisome-proliferator responsive element (PPRE) in the mouse HSL promoter by reporter assay in CV-1 cells using serial deletion and point mutants of the 5'-flanking region. Chromatin immunoprecipitation (ChIP) analysis revealed that both peroxisome-proliferator activated receptor (PPAR{gamma}) and retinoid X receptor (RXR{alpha}) interacted with the region. Binding of the PPAR{gamma}/RXR{alpha} heterodimer to the PPRE sequence was also confirmed by electrophoretic mobility shift assay. These results indicate that the HSL gene is transcriptionally regulated by PPAR{gamma}/RXR{alpha} heterodimer, and suggest that a cis-acting element regulates the HSL gene expression.

  3. Finite element simulation of rate-dependent magneto-active polymer response

    NASA Astrophysics Data System (ADS)

    Haldar, K.; Kiefer, B.; Menzel, A.

    2016-10-01

    This contribution is concerned with the embedding of constitutive relations for magneto-active polymers (MAP) into finite element simulations. To this end, a recently suggested, calibrated, and validated material model for magneto-mechanically coupled and rate-dependent MAP response is briefly summarized in its continuous and algorithmic settings. Moreover, the strongly coupled field equations of finite deformation magneto-mechanics are reviewed. For the purpose of numerical simulation, a finite element model is then established based on the usual steps of weak form representation, discretization and consistent linearization. Two verifying inhomogeneous numerical examples are presented in which a classical ‘plate with a hole’ geometry is equipped with MAP properties and subjected to different types of time-varying mechanical and magnetic loading.

  4. Three-Dimensional Finite Element Ablative Thermal Response and Thermostructural Design of Thermal Protection Systems

    NASA Technical Reports Server (NTRS)

    Dec, John A.; Braun, Robert D.

    2011-01-01

    A finite element ablation and thermal response program is presented for simulation of three-dimensional transient thermostructural analysis. The three-dimensional governing differential equations and finite element formulation are summarized. A novel probabilistic design methodology for thermal protection systems is presented. The design methodology is an eight step process beginning with a parameter sensitivity study and is followed by a deterministic analysis whereby an optimum design can determined. The design process concludes with a Monte Carlo simulation where the probabilities of exceeding design specifications are estimated. The design methodology is demonstrated by applying the methodology to the carbon phenolic compression pads of the Crew Exploration Vehicle. The maximum allowed values of bondline temperature and tensile stress are used as the design specifications in this study.

  5. Identification of peroxisome-proliferator responsive element in the mouse HSL gene.

    PubMed

    Yajima, Hiroaki; Kobayashi, Yumie; Kanaya, Tomoka; Horino, Yoko

    2007-01-12

    Hormone-sensitive lipase (HSL) catalyzes the rate-limiting step of lipolysis in adipose tissue. Several studies suggest that protein phosphorylation regulates the HSL enzymatic activity. On the other hand, the precise mechanism of the transcriptional regulation of the HSL gene remains to be elucidated. Here, we identified a functional peroxisome-proliferator responsive element (PPRE) in the mouse HSL promoter by reporter assay in CV-1 cells using serial deletion and point mutants of the 5'-flanking region. Chromatin immunoprecipitation (ChIP) analysis revealed that both peroxisome-proliferator activated receptor (PPARgamma) and retinoid X receptor (RXRalpha) interacted with the region. Binding of the PPARgamma/RXRalpha heterodimer to the PPRE sequence was also confirmed by electrophoretic mobility shift assay. These results indicate that the HSL gene is transcriptionally regulated by PPARgamma/RXRalpha heterodimer, and suggest that a cis-acting element regulates the HSL gene expression.

  6. Genomic Regulation of the Response of an Agroecosystem to Elements of Global Change

    SciTech Connect

    DeLucia, Evan, H.

    2011-06-03

    This document outlines some of the major accomplishments from this project: (1) New tools for analyzing and visualizing microarray data from soybean gene expression experiments; (2) Physiological, biochemical, and gene array evidence that acclimation of carbon metabolism to elevated CO{sub 2} is governed in significant part by changes in gene expression associated with respiratory metabolism; (3) Increased carbon assimilation in soybeans grown at elevated CO{sub 2} altered pools of carbohydrates and transcripts that control growth and expansion of young leaves; (4) Growth at elevated CO{sub 2} increases the abundance of transcripts controlling cell wall polysaccharide synthesis but not transcripts controlling lignin synthesis; (5) The total antioxidant capacity of soybeans varies among cultivars and in response to atmospheric change; (6) Accelerated leaf senescence at elevated O{sub 3} coincides with reduced abundance of transcripts controlling protein synthesis; (7) Growth under elevated CO{sub 2} increases the susceptibility of soybean to insect herbivores by increasing insect lifespan and fecundity through altered leaf chemistry and by defeating molecular induction of plant defenses; (8) Exposure to elevated CO{sub 2} and O{sub 3} alters flavonoid metabolism in soybean; (9) Exposure to elevated CO{sub 2} or O{sub 3} conferred resistance to soybean mosaic virus by cross inducing defense- and stress-related signaling pathways; and (10) Exposure to elevated CO{sub 2} accelerates decomposition by changing chemical and biotic properties of the soil.

  7. Effects of Pb on the oxidative stress and antioxidant response in a Pb bioaccumulator plant Vallisneria natans.

    PubMed

    Wang, Peifang; Zhang, Songhe; Wang, Chao; Lu, Jie

    2012-04-01

    The effects of Pb on photosynthetic pigments, oxidative stress and antioxidant response were assayed using biochemical and histochemical methods in leaves of Vallisneria natans (Lour.) Hara treated with 0-100 μM Pb(2+) for 0-6d. The Pb content increased with the increase of exposure duration and a highest Pb uptake value (about 9.4 mg Pbg(-1) dry weight) was obtained at 6d. Pb induced the accumulation of H(2)O(2) and O(2)(-). The increase of malondialdehyde content and the decrease of total chlorophyll and carotenoids were detected in V. natans under Pb stress. Activities of NAD(P)H oxidase, guaiacol peroxidase, glutathione reductase and ascorbate peroxidase increased at 75 μM Pb(2+) for 2-6 days, while activities of superoxide dismutase and catalase and the content of ascorbic acid increased within two days in plants exposed to 75 μM Pb(2+) and decreased thereafter. The Pb uptake and accumulation mechanism were discussed. PMID:22138147

  8. Antioxidant Systems from Pepper (Capsicum annuum L.): Involvement in the Response to Temperature Changes in Ripe Fruits

    PubMed Central

    Mateos, Rosa M.; Jiménez, Ana; Román, Paloma; Romojaro, Félix; Bacarizo, Sierra; Leterrier, Marina; Gómez, Manuel; Sevilla, Francisca; del Río, Luis A.; Corpas, Francisco J.; Palma, José M.

    2013-01-01

    Sweet pepper is susceptible to changes in the environmental conditions, especially temperatures below 15 °C. In this work, two sets of pepper fruits (Capsicum annuum L.) which underwent distinct temperature profiles in planta were investigated. Accordingly, two harvesting times corresponding to each set were established: Harvest 1, whose fruits developed and ripened at 14.9 °C as average temperature; and Harvest 2, with average temperature of 12.4 °C. The oxidative metabolism was analyzed in all fruits. Although total ascorbate content did not vary between Harvests, a shift from the reduced to the oxidized form (dehydroascorbate), accompanied by a higher ascorbate peroxidase activity, was observed in Harvest 2 with respect to Harvest 1. Moreover, a decrease of the ascorbate-generating enzymatic system, the γ-galactono-lactone dehydrogenase, was found at Harvest 2. The activity values of the NADP-dependent dehydrogenases analyzed seem to indicate that a lower NADPH synthesis may occur in fruits which underwent lower temperature conditions. In spite of the important changes observed in the oxidative metabolism in fruits subjected to lower temperature, no oxidative stress appears to occur, as indicated by the lipid peroxidation and protein oxidation profiles. Thus, the antioxidative systems of pepper fruits seem to be involved in the response against temperature changes. PMID:23644886

  9. Response of antioxidative enzymes and apoplastic bypass transport in Thlaspi caerulescens and Raphanus sativus to cadmium stress.

    PubMed

    Benzarti, Saoussen; Hamdi, Helmi; Mohri, Shino; Ono, Yoshiro

    2010-01-01

    A hydroponics experiment using hyperaccumulator Thlaspi caerulescens (alpine pennycress) and non-specific accumulator Raphanus sativus (common radish) was conducted to investigate the short-term effect of increasing Cd concentrations (0, 25, 50, 75, 100 microM) on metal uptake, chlorophyll content, antioxidative enzymes, and apoplastic bypass flow. As expected, T. caerulescens generally showed better resistance to metal stress, which was reflected by higher Cd accumulation within plant tissues with no signs of chlorosis, or wilt. Glutathione reductase (GR) and superoxide dismutase (SOD) activities in fresh leaves were monitored as the plant metal-detoxifying response. In general, both plant species exhibited an increase trend of GR activity before declining at 100 microM likely due to excessive levels of phytotoxic Cd. SOD activity exhibited almost a similar variation pattern to GR and decreased also at 100 microM Cd. For both plant species, fluorescent PTS uptake (8-hydroxy-1,3,6-pyrenetrisulphonic acid) increased significantly with metal level in exposure solutions indicating that Cd has a comparable effect to drought or salinity in terms of the gain of relative importance in apoplastic bypass transport under such stress conditions.

  10. The Effects of Cadmium Exposure on Fitness-Related Traits and Antioxidant Responses in the Wolf Spider, Pardosa pseudoannulata.

    PubMed

    Li, Chang-Chun; Li, Guo-Yuan; Yun, Yue-Li; Chen, Jian; Zhang, Zeng-Tao; Peng, Yu

    2016-07-01

    The objective of the present study was to assess the ecotoxicological responses of Pardosa pseudoannulata to a common environmental pollutant, cadmium. Third-instar spiderlings and adult spiders were exposed to sublethal concentrations of CdCl2 solution in their drinking water. The Cd content in P. pseudoannulata adults increased significantly with the number of days of exposure to a 0.2 mM CdCl2 solution, when exposed to 2 mM CdCl2 solution, the Cd content in the spiders increased sharply in the first two (male) or three (female) weeks, and then no significant changes were recorded following with the next three (male) or two (female) weeks exposure. Exposure of spiders to Cd contaminated drinking water resulted in reduced body mass, delayed development, fewer eggs and increased mortality. Significantly higher activities of superoxide dismutase, catalase and glutathione-S-transferase were recorded in the spiders after 7 day exposure to 0.2 mM CdCl2 solution. However, longer-term exposures or increased Cd concentrations did not result in significantly higher antioxidant enzyme activity relative to control treatment. PMID:27194251

  11. Grape