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Sample records for antioxidant response element

  1. Bisphenol A activates the Nrf1/2-antioxidant response element pathway in HEK 293 cells.

    Science.gov (United States)

    Chepelev, Nikolai L; Enikanolaiye, Mutiat I; Chepelev, Leonid L; Almohaisen, Abdulrahman; Chen, Qixuan; Scoggan, Kylie A; Coughlan, Melanie C; Cao, Xu-Liang; Jin, Xiaolei; Willmore, William G

    2013-03-18

    Bisphenol A (BPA) is used in the production of polycarbonate plastics and epoxy resins for baby bottles, liners of canned food, and many other consumer products. Previously, BPA has been shown to reduce the activity of several antioxidant enzymes, which may contribute to oxidative stress. However, the underlying mechanism of the BPA-mediated effect upon antioxidant enzyme activity is unknown. Antioxidant and phase II metabolizing enzymes protect cells from oxidative stress and are transcriptionally activated by Nrf1 and Nrf2 factors through their cis-regulatory antioxidant response elements (AREs). In this work, we have assessed the effect of BPA on the Nrf1/2-ARE pathway in cultured human embryonic kidney (HEK) 293 cells. Surprisingly, glutathione and reactive oxygen species (ROS) assays revealed that BPA application created a more reduced intracellular environment in cultured HEK 293 cells. Furthermore, BPA increased the transactivation activity of ectopic Nrf1 and Nrf2 and increased the expression of ARE-target genes ho-1 and nqo1 at high (100-200 μM) BPA concentrations only. Our study suggests that BPA activates the Nrf1/2-ARE pathway at high (>10 μM) micromolar concentrations. PMID:23360430

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

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Yanyan [Institute for Chemical Safety Sciences, The Hamner Institutes for Health Sciences, 6 Davis Drive, Research Triangle Park, NC 27709 (United States); The First Affiliated Hospital, China Medical University, Shenyang 110001 (China); Xue, Peng [Institute for Chemical Safety Sciences, The Hamner Institutes for Health Sciences, 6 Davis Drive, Research Triangle Park, NC 27709 (United States); Key Laboratory of the Public Health Safety, Ministry of Education, School of Public Health, Fudan University, Shanghai (China); Hou, Yongyong [Institute for Chemical Safety Sciences, The Hamner Institutes for Health Sciences, 6 Davis Drive, Research Triangle Park, NC 27709 (United States); School of Public Health, China Medical University, Shenyang 110001 (China); Zhang, Hao [Key Laboratory of the Public Health Safety, Ministry of Education, School of Public Health, Fudan University, Shanghai (China); Zheng, Hongzhi [Institute for Chemical Safety Sciences, The Hamner Institutes for Health Sciences, 6 Davis Drive, Research Triangle Park, NC 27709 (United States); The First Affiliated Hospital, China Medical University, Shenyang 110001 (China); Zhou, Tong [Institute for Chemical Safety Sciences, The Hamner Institutes for Health Sciences, 6 Davis Drive, Research Triangle Park, NC 27709 (United States); Qu, Weidong [Key Laboratory of the Public Health Safety, Ministry of Education, School of Public Health, Fudan University, Shanghai (China); Teng, Weiping [The First Affiliated Hospital, China Medical University, Shenyang 110001 (China); Zhang, Qiang; Andersen, Melvin E. [Institute for Chemical Safety Sciences, The Hamner Institutes for Health Sciences, 6 Davis Drive, Research Triangle Park, NC 27709 (United States); Pi, Jingbo, E-mail: jingbopi@gmail.com [Institute for Chemical Safety Sciences, The Hamner Institutes for Health Sciences, 6 Davis Drive, Research Triangle Park, NC 27709 (United States); School of Public Health, China Medical University, Shenyang 110001 (China)

    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.

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

    International Nuclear Information System (INIS)

    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

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

    International Nuclear Information System (INIS)

    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

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

    Science.gov (United States)

    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)...

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

    Science.gov (United States)

    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...

  7. 31. Antioxidant and hypoxia induce the human antioxidant response element-mediated expression of NAD(P) H: quinone oxidoreductase1 gene

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    Background: NAD(P)H: quinone oxidoreductase 1 (NQO1) is an obligate two-electron reductase that is involved in protection of cells against redox cycling, oxidative stress, and neoplasia. and can also bioactivate certain antitumor quinones. Many antioxidants are cancer chemopreventive agents, and tumour hypoxia are now being exploited in cancer treatment which shows considerable promise to overcome the resistance to cancer chemotherapy. Antioxidant response element (ARE) is sensitive to perturbations of cellular redox states. Our previous studies have shown that β-tyrosol (β-TY), as a phenolic antioxidant, can protects cells against DNA damage resulting from toxic H2O2. Aim: We take the present study with the goal of whether antioxidants such as β-tyrosol, butylated hydroxyanisole(BHA) and β-Naphthooflavone(β-NF) and hypoxia (pO2 0.1% -0.5%) can induce gene expression of NQO1, inhibit proliferation of human hepatoma cells SMMC-7721 and the relationship between them; whether ARE can mediate gene expression in response to antioxidans and hypoxia. Methods: SMMC-7721 human hepatoma cells are planted in plates, grown for 24h. and exposed to antioxidants and hypoxia, each alone or in combination for another 24h. The enzyme activity was determinied by spectrophotometric assay using direct measurement of NQO1 from cells cultured in Microtiter wells. Semi-quantitative reverse transcription-PCR (RT-PCR) technique was used to measure NQO1 mRNA levets. Proliferation was estimated using the crystal violet staining technique. Electrophoretic mobility shift assay (EMSA) was employed to assess protein binding to the ARE under all of These conditions. Hypoxia cells were harvested in an anaerobic chamber at the end of the incubation period. Results: Antioxidant (90ug/ml β-TY、60μmol/L BHA、80μmol/L β-NF) potently induce an increase in the activity of NQO1. From 60μg/ml to 90μg/ml, β-TY caused NQO1 activity enhancement in a dose-dependent manner The NQO1 activity induced

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

    Science.gov (United States)

    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.

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

    Directory of Open Access Journals (Sweden)

    Sergio Montes

    2015-01-01

    Full Text Available 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.

  10. Vitamins, trace elements, and antioxidant status in dementia disorders

    OpenAIRE

    Tabet, N.; Mantle, D; WALKER, Z.; Orrell, M.

    2001-01-01

    Antioxidants, such as vitamins C and E, have been proposed for the treatment of dementia disorders. Although other vitamins and trace elements may also have antioxidant-enhancing activities, it is not known whether the overall antioxidant status in dementia patients is associated with the intake level of these vitamins and trace elements. In this study, we assessed the levels of vitamins and trace elements in the diet of patients with Alzheimer's disease (AD), vascular dementia (VaD), and dem...

  11. 5MeCDDO Blocks Metabolic Activation but not Progression of Breast, Intestine, and Tongue Cancers. Is Antioxidant Response Element a Prevention Target?

    Science.gov (United States)

    Lubet, Ronald A; Townsend, Reid; Clapper, Margie L; Juliana, M Margaret; Steele, Vernon E; McCormick, David L; Grubbs, Clinton J

    2016-07-01

    The preventive efficacy of the triterpenoid 5MeCDDO was tested in two models of mammary cancer, the Min model of intestinal cancer, and a chemically induced model of head and neck cancer. In one model of mammary cancer, female Sprague-Dawley rats were administered MNU at 50 days of age, and 5MeCDDO (27 ppm) was administered in the diet beginning 5 days later for the duration of the study; 5MeCDDO was ineffective. In contrast, in a model examining initiation of mammary cancers by the procarcinogen dimethyl-benzanthracene, 5, 6-benzoflavone (500 ppm, an Ah receptor agonist) or 5MeCDDO (27 or 2.7 ppm) decreased tumor multiplicity by 90%, 80%, and 50%, respectively. This anti-initiating effect which is presumably mediated by altered metabolic activation parallels our observation that 5MeCDDO induced proteins of various antioxidant response element (ARE)-related phase II drug-metabolizing enzymes [e.g., GST Pi, AKR 7A3 (aflatoxicol), epoxide hydrolase, and quinone reductase] in the liver. 5MeCDDO tested in the 4-nitroquinoline-l-oxide (4-NQO) head and neck cancer model failed to decrease tumor incidence or invasiveness. In the Min mouse model of intestinal cancer, a high dose of 5MeCDDO (80 ppm) was weakly effective in reducing adenoma multiplicity [∼30% (P < 0.05)]; however, a lower dose was totally ineffective. These findings question whether measuring increased levels of certain ARE-related genes (e.g., quinone reductase, GST Pi), indicating decreased carcinogen activation are sufficient to imply general chemopreventive efficacy of a given agent or mixture. Cancer Prev Res; 9(7); 616-23. ©2016 AACR. PMID:27150634

  12. Antioxidant Vitamins and Trace Elements in Critical Illness.

    Science.gov (United States)

    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

  13. Arsenic induces NAD(P)H-quinone oxidoreductase I by disrupting the Nrf2 x Keap1 x Cul3 complex and recruiting Nrf2 x Maf to the antioxidant response element enhancer.

    Science.gov (United States)

    He, Xiaoqing; Chen, Michael G; Lin, Gary X; Ma, Qiang

    2006-08-18

    The ubiquitous toxic metalloid arsenic elicits pleiotropic adverse and adaptive responses in mammalian species. The biological targets of arsenic are largely unknown at present. We analyzed the signaling pathway for induction of detoxification gene NAD(P)H-quinone oxidoreductase (Nqo1) by arsenic. Genetic and biochemical evidence revealed that induction required cap 'n' collar basic leucine zipper transcription factor Nrf2 and the antioxidant response element (ARE) of Nqo1. Arsenic stabilized Nrf2 protein, extending the t(1/2) of Nrf2 from 21 to 200 min by inhibiting the Keap1 x Cul3-dependent ubiquitination and proteasomal turnover of Nrf2. Arsenic markedly inhibited the ubiquitination of Nrf2 but did not disrupt the Nrf2 x Keap1 x Cul3 association in the cytoplasm. In the nucleus, arsenic, but not phenolic antioxidant tert-butylhydroquinone, dissociated Nrf2 from Keap1 and Cul3 followed by dimerization of Nrf2 with a Maf protein (Maf G/Maf K). Chromatin immunoprecipitation demonstrated that Nrf2 and Maf associated with the endogenous Nqo1 ARE enhancer constitutively. Arsenic substantially increased the ARE occupancy by Nrf2 and Maf. In addition, Keap1 was shown to be ubiquitinated in the cytoplasm and deubiquitinated in the nucleus in the presence of arsenic without changing the protein level, implicating nuclear-cytoplasmic recycling of Keap1. Our data reveal that arsenic activates the Nrf2/Keap1 signaling pathway through a distinct mechanism from that by antioxidants and suggest an "on-switch" model of Nqo1 transcription in which the binding of Nrf2 x Maf to ARE controls both the basal and inducible expression of Nqo1. PMID:16785233

  14. 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.

    Science.gov (United States)

    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

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

    Science.gov (United States)

    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.

  16. Evaluation of Ayurvedic plants for stimulating intrinsic antioxidant responses

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    Sunil Dutt Shukla

    2012-07-01

    Full Text Available 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 an already large catalogue.

  17. Studies on tender wheatgrass: estimation of elemental content, bioaccessibility of essential elements and antioxidant activity

    International Nuclear Information System (INIS)

    Tender wheatgrass is being consumed by human beings in juice form or as it is due to its antioxidant potential and medicinal value. Systematic studies were carried out to (i) estimate elemental profiles as a function of growth period and conditions, bioaccessibility of different elements and the antioxidant potential of the tender wheatgrass, (ii) determine the optimum growth period for obtaining maximum benefit and (iii) examine the possible correlation between antioxidant potential and mineral content. Wheatgrass was grown in four different conditions namely (i) tap water, (ii) tap water with nutrients, (iii) soil and tap water and (iv) soil with nutrient solution. The studies were carried out on the wheatgrass of 5-20 days old. For comparison with laboratory grown wheatgrass, a set of commercially available wheatgrass tablets and wheat seeds were also studied. Instrumental neutron activation analysis (INAA) was used for concentration determination of elements in the wheatgrass, wheat seeds and wheatgrass tablets. A total of 15 elements like Na, K, Ca, Mg, Mn, Br, Fe and Zn were determined in the samples of shoots and roots of tender wheatgrass. A comparison with the recommended dietary allowance (RDA) of different essential elements with that in tender wheatgrass revealed that wheatgrass is a good source of minerals for health benefits rather than a food supplement. Bioaccessible fractions of various elements were estimated by a chemical NAA method by subjecting the samples to in vitro gastric and gastro-intestinal digestion followed by NAA. The bioaccessibility concentrations by both the measurements were in the range of 9-60%. It was found that bioaccessibility of the elements studied was the highest from fresh wheatgrass and the lowest from wheat seeds. Accuracy of the NAA method was evaluated by analyzing two biological reference materials, SRM 1573a (Tomato leaves) from NIST, USA and ICHTJ CTA-vtl-2 (Tobacco leaves) from INCT, Poland. The antioxidant

  18. Salt tolerance in Solanum pennellii: antioxidant response and related QTL

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    Şığva Hasan Ö

    2010-04-01

    Full Text Available Abstract Background Excessive soil salinity is an important problem for agriculture, however, salt tolerance is a complex trait that is not easily bred into plants. Exposure of cultivated tomato to salt stress has been reported to result in increased antioxidant content and activity. Salt tolerance of the related wild species, Solanum pennellii, has also been associated with similar changes in antioxidants. In this work, S. lycopersicum M82, S. pennellii LA716 and a S. pennellii introgression line (IL population were evaluated for growth and their levels of antioxidant activity (total water-soluble antioxidant activity, major antioxidant compounds (phenolic and flavonoid contents and antioxidant enzyme activities (superoxide dismutase, catalase, ascorbate peroxidase and peroxidase under both control and salt stress (150 mM NaCl conditions. These data were then used to identify quantitative trait loci (QTL responsible for controlling the antioxidant parameters under both stress and nonstress conditions. Results Under control conditions, cultivated tomato had higher levels of all antioxidants (except superoxide dismutase than S. pennellii. However, under salt stress, the wild species showed greater induction of all antioxidants except peroxidase. The ILs showed diverse responses to salinity and proved very useful for the identification of QTL. Thus, 125 loci for antioxidant content under control and salt conditions were detected. Eleven of the total antioxidant activity and phenolic content QTL matched loci identified in an independent study using the same population, thereby reinforcing the validity of the loci. In addition, the growth responses of the ILs were evaluated to identify lines with favorable growth and antioxidant profiles. Conclusions Plants have a complex antioxidant response when placed under salt stress. Some loci control antioxidant content under all conditions while others are responsible for antioxidant content only under

  19. Evaluation of Ayurvedic plants for stimulating intrinsic antioxidant responses

    OpenAIRE

    Sunil Dutt Shukla; Maheep eBhatnagar; Sukant eKhurana

    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...

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

    OpenAIRE

    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...

  1. 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.

    Science.gov (United States)

    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.

  2. Antioxidant responses of wheat plants under stress

    Directory of Open Access Journals (Sweden)

    Andréia Caverzan

    2016-03-01

    Full Text Available 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.

  3. Total antioxidant capacity, total phenolic content and mineral elements in the fruit peel of Myrciaria cauliflora

    OpenAIRE

    Clináscia Rodrigues Rocha Araújo; Thiago de Mello Silva; Monica Lopes; Paula Villela; Antônio Flávio de Carvalho Alcântara; Nísia Andrade Villela Dessimoni-Pinto

    2013-01-01

    The in vitro antioxidant capacity, total phenolic content and mineral elements of the fruit peel of Myrciaria cauliflora were investigated. The antioxidant capacity was analyzed by the diphenylpicrylhydrazyl (DPPH), 2,2'-azino-bis(3-ethylbenzthiazoline-6-sulfonic acid) (ABTS), ferric reducing antioxidant power (FRAP) and β-carotene methods. The assays based on the DPPH (EC50 = 3.18 g sample/g DPPH), ABTS•+ (1017 μmol Trolox/g sample), FRAP (1676 µM Fe2SO4/g sample) and β-carotene/linoleic aci...

  4. Integrating Environmentally Responsive Elements in Buildings

    OpenAIRE

    Heiselberg, Per; Andresen, Inger; Perino, Marco; van der Aa, Ad

    2006-01-01

    Significant improvement have been achieved on efficiency improvements of specific building elements like the building envelope and building equipment and services and whilst most building elements still offer opportunities for efficiency improvements, the greatest future potential lie with technologies that promote the integration of responsive building elements and building services in integrated building concepts. In order to address some of these issues an international research effort, IE...

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

    Science.gov (United States)

    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. Can packaging elements elicit consumers’ emotional responses?

    DEFF Research Database (Denmark)

    Liao, Lewis; Corsi, Armando; Lockshin, Larry;

    Emotion has been an important concept in many areas of consumer research such as judgment, decision-making and advertising. Little research has been done on emotion in packaging adopting the physiological measures used in other areas. This paper draws on past studies in advertising that measure...... emotional responses toward image, colour and font, and apply them to packaging research. The study tests the extent at which packaging can elicit consumers’ spontaneous emotional response for each of those three elements, by using skin conductance, facial electromyography (EMG) and selfassessment scales....... The results show that packaging can elicit an emotional response via different elements. The paper also raises concerns about the accuracy of using selfreport measures of emotional responses to packaging research....

  7. Antioxidants

    Science.gov (United States)

    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 ...

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

    Science.gov (United States)

    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.

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

    Science.gov (United States)

    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

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

    Science.gov (United States)

    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 filariasis.

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

    Science.gov (United States)

    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.

  12. Evolution of the iron-responsive element

    OpenAIRE

    Piccinelli, Paul; Samuelsson, Tore

    2007-01-01

    An RNA hairpin structure referred to as the iron-responsive element (IRE) and iron regulatory proteins (IRPs) are key players in the control of iron metabolism in animal cells. They regulate translation initiation or mRNA stability, and the IRE is found in a variety of mRNAs, such as those encoding ferritin, transferrin receptor (Tfr), erythroid aminolevulinic acid synthase (eALAS), mitochondrial aconitase (mACO), ferroportin, and divalent metal transporter 1 (DMT1). We have studied the evolu...

  13. Integrating Responsive Building Elements in Buildings

    DEFF Research Database (Denmark)

    Haase, Matthias; Amato, Alex; Heiselberg, Per

    2006-01-01

    energy strategies to develop guidelines and procedures for estimation of environmental performance of responsive building elements and integrated building concepts This paper introduces the ideas of this collaborative work and discusses its usefulness for Hong Kong and China. Special focus was put......There is a global need for a more sustainable building development. About 50% of energy is used in buildings indicating that buildings provide a considerable potential for operational energy savings. Studies were conducted with the following objectives: to perform a state-of-the-art review...

  14. 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

    Energy Technology Data Exchange (ETDEWEB)

    Murugaiyan, Jayaseelan; Rockstroh, Maxie; Wagner, Juliane [Department of Proteomics, Helmholtz-Centre for Environmental Research — UFZ, Permoserstr. 15, 04318 Leipzig (Germany); Baumann, Sven [Department of Metabolomics, Helmholtz-Centre for Environmental Research — UFZ, Permoserstr. 15, 04318 Leipzig (Germany); Schorsch, Katrin [Department of Proteomics, Helmholtz-Centre for Environmental Research — UFZ, Permoserstr. 15, 04318 Leipzig (Germany); Trump, Saskia; Lehmann, Irina [Department of Environmental Immunology, Helmholtz-Centre for Environmental Research — UFZ, Permoserstr. 15, 04318 Leipzig (Germany); Bergen, Martin von [Department of Proteomics, Helmholtz-Centre for Environmental Research — UFZ, Permoserstr. 15, 04318 Leipzig (Germany); Department of Environmental Immunology, Helmholtz-Centre for Environmental Research — UFZ, Permoserstr. 15, 04318 Leipzig (Germany); Department of Biotechnology, Chemistry and Environmental Engineering, Aalborg University, Aalborg (Denmark); Tomm, Janina M., E-mail: Janina.tomm@ufz.de [Department of Proteomics, Helmholtz-Centre for Environmental Research — UFZ, Permoserstr. 15, 04318 Leipzig (Germany)

    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.

  15. Physiological and biochemical responses of thyme plants to some antioxidants

    Directory of Open Access Journals (Sweden)

    SALWA A. ORABI

    2014-11-01

    Full Text Available Orabi SA, Talaat IM, Balbaa LK. 2014. Physiological and biochemical responses of thyme plants to some antioxidants. Nusantara Bioscience 6: 118-125. Two pot experiments were conducted to investigate the effect of tryptophan, nicotinamide and α-tocopherol (each at 50 and 100 mg/L on plant growth, essential oil yield and its main constituents. All treatments significantly promoted plant height, and increased fresh and dry mass (g/plant of thyme (Thymus vulgaris L.. The treatment with 100 mg/L nicotinamide showed increasing in total potassium mainly in the first cut. Total soluble sugars, oil percentage and oil yield and protein recorded increments with tryptophan treatments. Treatment of Thymus plants with 100 mg/L nicotinamide observed the highest percentage of thymol (67.61%. Oxygenated compounds recorded the highest value with 50 mg/L α-tocopherol treatment, while the maximum non-oxygenated ones resulted from the application of 100 mg/L nicotinamide. All treatments under study significantly affected the activity of oxidoreductase enzymes (POX and PPO. Nicotinamide at the concentration of 100 mg/L recorded the highest increments in APX and GR and the lowest values in oxidoreductase enzyme activities added to the lowest values of lipid peroxidation to enhance the best protection of thyme plants.

  16. Relationship between serum trace elements and antioxidant capacity indexes in women of hypertensive disorder complicating pregnancy

    Institute of Scientific and Technical Information of China (English)

    Yang Liu; Mei Xu; Ying Jiang; Yan Zhang

    2016-01-01

    Objective:To analyze the relationship between serum trace elements, antioxidant capacity index and hypertensive disorder complicating pregnancy (HDCP). Methods: Forty cases of normal healthy pregnant women, twenty-one pregnant women with high blood pressure, twenty-eight pregnant women with early stage of mild preeclampsia and twenty-two pregnant women with early stage of severe preeclampsia were selected respectively. Then, the differences of blood routine examination and blood coagulation function of the four groups were compared. At the same time, the levels of the serum trace elements and oxidative stress related indexes in the placental villi tissue were determined by flame atomic absorption spectrometry. Results:The white blood cells and hematocrit of HDCP pregnant women were significantly higher than those of normal healthy pregnant women;platelet and fibrinogen levels were obviously lower than those of normal healthy pregnant women, while thrombin time was shorter than that of normal healthy pregnant women;levels of serum copper, zinc and manganese were also significantly lower than whose of normal healthy pregnant women, while iron level was distinctly higher than that of normal healthy pregnant women. The differences between groups were statistically significant. The activities of SOD and GSH-PX in the placental villi tissue of HDCP pregnant women were significantly smaller than those of normal healthy pregnant women, while the Hcy level was higher than that of normal healthy pregnant women. The differences between groups were statistically significant. Conclusions:Pregnant women with HDCP has both imbalance of trace elements and redox system equilibrium, so we should strengthen the determination of the trace elements and redox related indexes of HDCP pregnant women to ensure health of maternal and child.

  17. Antioxidant responses in Mesopodopsis zeylanica at varying salinity to detect mercury influence in culture ponds

    Digital Repository Service at National Institute of Oceanography (India)

    Verlecar, X.N.; Das, P.B.; Jena, K.; Maharana, D.; Desai, S.R.

    Antioxidant responses in the estuarine mysid, Mesopodopsis zeylanica, were used to assess mercury (Hg) metal contamination in relation to salinity. Natural mysids acclimatized at 5 psu were subjected to laboratory exposures of 5, 15, and 25 psu...

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

    Science.gov (United States)

    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...

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

    Science.gov (United States)

    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. PMID:26169729

  20. ANTIOXIDATIVE RESPONSE OF VARIOUS CULTIVARS OF SORGHUM ( SORGHUM BICOLOR L.) TO DROUGHT STRESS

    OpenAIRE

    Gurpreet Singh; Nidhi Sharma

    2013-01-01

    The present study was conducted with the aim to identify the response of antioxidant enzyme activities in seedlings of different sorghum cultivars under mannitol stress. Seven-day old seedlings were subjected to 100-500 mM mannitol stress which resulted in the decreases in shoot/root length and relative water content thus indicating the primary response to these tissues at phenotypic level. The level of lipid peroxidation as well as the specific activity of antioxidant enzymes such as peroxid...

  1. Ablative Thermal Response Analysis Using the Finite Element Method

    Science.gov (United States)

    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.

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

    Science.gov (United States)

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

    Science.gov (United States)

    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.

  4. Antioxidative enzymes in the response of buckwheat (Fagopyrum esculentum Moench to complete submergence

    Directory of Open Access Journals (Sweden)

    Stanisavljević N.S.

    2011-01-01

    Full Text Available Oxidative stress and antioxidative defense system activity were studied in buckwheat leaves after complete submergence and re-aeration. The levels of H2O2 and lipid peroxidation were found to be significantly higher in stressed than in untreated buckwheat leaves. Enzymes catalyzing the degradation of H2O2 and peroxides were shown to participate actively, whereas superoxide dismutase did not take part in the buckwheat leaf response to flooding stress. The most prominent increase in antioxidative enzyme activities was noticed upon return to air, when the strongest oxidative stress occurred and the need for antioxidative defense was the greatest.

  5. Optimization of Ultrasonic Extraction of Phenolic Antioxidants from Green Tea Using Response Surface Methodology

    OpenAIRE

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

    2013-01-01

    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 ...

  6. ANTIOXIDANT VITAMINS AND THE RISK OF ENDOMETRIAL CANCER: A DOSE-RESPONSE META-ANALYSIS

    OpenAIRE

    Elisa V Bandera; Gifkins, Dina M.; Moore, Dirk F.; McCullough, Marjorie L; Lawrence H Kushi

    2008-01-01

    Antioxidant vitamins may reduce cancer risk by limiting oxidative DNA damage. To summarize and quantify the current epidemiologic evidence of an association between antioxidant vitamin intake and endometrial cancer we conducted a systematic literature review and meta-analysis. One cohort and 12 case-control studies presenting relevant risk estimates were identified by conducting bibliographical searches through June 2008. Dose-response meta-analyses were conducted for beta-carotene, vitamin C...

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

    Science.gov (United States)

    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.

  8. Prediction of nuclear hormone receptor response elements.

    Science.gov (United States)

    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. PMID:15563547

  9. Modulation of antioxidant enzymes as radioprotector mechanism of oligo elements and lachesis muta in normal tissues

    International Nuclear Information System (INIS)

    The therapeutic use of the ionizing radiations (IR) it has acquired great relevance in the last decades although their effects are not selective and they are also manifested on the normal tissues. In previous works we demonstrate the radioprotector effect that the combination of oligo elements Zinc, Selenium and Manganese associated to the snake poison Lachesis muta (O-LM) it exercises on the small intestine and the bone marrow of irradiated mouse. The objective of this work was to study the molecular mechanisms, and particularly the paper of the anti-oxidant superoxide dismutases enzymes (MnSOD and Cu/ZnSOD), Catalase (CAT), and Glutathione Peroxidase (GPx), in the radioprotector action that exercises the combination O-LM. Four groups of mice were used: A) control; B) treated with O-LM; C) irradiated; D) irradiated and treated with O-LM. The two treated groups were injected daily via s.c. with 0,1 ml of O-LM from 30 days before the irradiation and until to 4 days later. The two irradiated groups received 10 Gy in whole body the day 30. The day 35 all the animals were sacrificed. The histological intestinal cuts of the mucous one were evaluated by tint with hematoxyline-eosin; the presence of apoptotic cells it was determined by the Tunel method (Apoptag kit); the expression of PCNA (nuclear antigen of proliferating cells), MnSOD, CuZnSOD, CAT and GPx, by immunohistochemistry. The results demonstrated that in the lot D it was preserved totally the histology of the intestinal mucous. In the control A it was observed PCNA expression in the crypts, of MnSOD in the hairiness and CuZnSOD, CAT and Gpx in both. The change produced by O-LM (group B) it was the increase of PCNA, of CAT and the appearance of MnSOD in the crypts. On the other hand, the irradiation (C) it produced a marked descent in the GPx, the complete disappearance of PCNA and an increase of the apoptotic cells. The group D showed that O-LM it reverted totally the effect of the RI on the expression of PCNA

  10. Yields, Phenolic Profiles and Antioxidant Activities of Ziziphus jujube Mill. in Response to Different Fertilization Treatments

    Directory of Open Access Journals (Sweden)

    Min Wang

    2013-09-01

    Full Text Available 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.

  11. Response Surface Stochastic Finite Element Method of Composite Structure

    Directory of Open Access Journals (Sweden)

    Cai Deyong

    2016-01-01

    Full Text Available Response Surface Method (RSM has been applied to structural reliability problems successfully in many areas. Finite Element Method (FEM is one of the most widely used computational methods, which permit the analysis and design of large-scale engineering systems. In order to obtain a reliability analysis method of composite structure with satisfactory accuracy and computational efficiency, RSM and FEM were combined by secondary development of ABAQUS. Response Surface Stochastic Finite Element Method (RSSFEM which can solve the reliability problems of composite structure was developed. The numerical accuracy and the computational efficiency of the developed method were demonstrated by comparison with Monte-Carlo Stochastic Finite Element Method (MCSFEM.

  12. Finite Element Model Updating Using Response Surface Method

    CERN Document Server

    Marwala, Tshilidzi

    2007-01-01

    This paper proposes the response surface method for finite element model updating. The response surface method is implemented by approximating the finite element model surface response equation by a multi-layer perceptron. The updated parameters of the finite element model were calculated using genetic algorithm by optimizing the surface response equation. The proposed method was compared to the existing methods that use simulated annealing or genetic algorithm together with a full finite element model for finite element model updating. The proposed method was tested on an unsymmetri-cal H-shaped structure. It was observed that the proposed method gave the updated natural frequen-cies and mode shapes that were of the same order of accuracy as those given by simulated annealing and genetic algorithm. Furthermore, it was observed that the response surface method achieved these results at a computational speed that was more than 2.5 times as fast as the genetic algorithm and a full finite element model and 24 ti...

  13. Effects of the amplitude and frequency of salinity fluctuations on antioxidant responses in juvenile tongue sole, Cynoglossus semilaevis

    OpenAIRE

    Sachin O. Khairnar; Xiangli Tian; Shuanglin Dong; Ziheng Fang; Bhavesh V. Solanki; Holeyappa A. Shanthanagouda

    2016-01-01

    To understand the tolerance of tongue sole, Cynoglossus semilaevis, to varying salinities, the effects of the amplitude (2, 4, 6 and 8 g/L) and frequency (2, 4 and 8 days) of salinity fluctuations on the activities of antioxidant responses, including acidic phosphatase (ACP), alkaline phosphatase (AKP), catalase (CAT) and superoxide dismutase (SOD) from antioxidant system in liver, muscle, gills and kidney, were investigated in this study. The results showed that the antioxidant responses of ...

  14. Evaluation of Antioxidant Activity, Polyphenolic Compounds, Amino Acids and Mineral Elements of Representative Genotypes of Lonicera edulis

    Directory of Open Access Journals (Sweden)

    Jiri Sochor

    2014-05-01

    Full Text Available The aim of this study was to evaluate the bioactive substances in 19 berry cultivars of edible honeysuckle (Lonicera edulis. A statistical evaluation was used to determine the relationship between the content of selected bioactive substances and individual cultivars. Regarding mineral elements, the content of sodium was measured using potentiometry and spectrophotometry. The content of selected polyphenolic compounds with high antioxidant activity was determined by a HPLC–UV/ED method. The total amount of polyphenols was determined by the Folin-Ciocalteu method. The antioxidant activity was determined using five methods (DPPH, FRAP, ABTS, FR and DMPD that differ in their principles. The content of 13 amino acids was determined by ion-exchange chromatography. The experimental results obtained for the different cultivars were evaluated and compared by statistical and bioinformatic methods. A unique feature of this study lies in the exhaustive analysis of the chosen parameters (amino acids, mineral elements, polyphenolic compounds and antioxidant activity during one growing season.

  15. Evidence for oxidative stress and defective antioxidant response in guinea pigs with tuberculosis.

    Directory of Open Access Journals (Sweden)

    Gopinath S Palanisamy

    Full Text Available 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

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

    Science.gov (United States)

    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

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

    Science.gov (United States)

    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.

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

    Science.gov (United States)

    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.

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

    Science.gov (United States)

    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

  20. Role of antioxidant vitamins and trace elements in mastitis in dairy cows

    Directory of Open Access Journals (Sweden)

    Feng Li Yang

    2015-03-01

    Full Text Available Mastitis is associated with release of free radicals, increased total oxidant capacity and decreased total antioxidants capacity in milk. Antioxidant vitamins and minerals protect the body from free radicals either by directly scavenging free radicals or by inhibiting the activity of oxidizing enzymes. The supplementation of mastitic dairy cows with antioxidant vitamins as vitamin A (VA and β-carotene (BC, vitamin C (VC, vitamin E (VE, and antioxidant minerals as selenium (Se, Zinc (Zn and copper (Cu is very important to help the animal recover early. The aim of this review was to discuss the oxidative stress in dairy cows’ mastitis, and the roles of VA and BC, VC, VE, Se, Zn, and Cu in mastitis of dairy cows. Before deciding to supplement dairy cow rations with the levels of vitamins and minerals, dairy farmers should have their animal feeds tested and their rations evaluated by a competent dairy cow nutritionist and a trustworthy laboratory to be sure what levels of supplementation may be warranted. While inadequate intake and absorption of certain nutrients may result in a weakened immune system and perhaps more mastitis during the lactation period, unjustified supplementation can be expensive and lead to other animal health problems.

  1. Effect of Antioxidant Mineral Elements Supplementation in the Treatment of Hypertension in Albino Rats

    Directory of Open Access Journals (Sweden)

    S. A. Muhammad

    2012-01-01

    Full Text Available 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.

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

    Science.gov (United States)

    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 mercury contamination in combination with their specific organ distribution (p 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.

  3. Cadmium exposure route affects antioxidant responses in the mayfly Centroptilum triangulifer

    Energy Technology Data Exchange (ETDEWEB)

    Xie Lingtian [Department of Environmental and Molecular Toxicology, North Carolina State University, Raleigh, NC 27695 (United States); Buchwalter, David B., E-mail: david_buchwalter@ncsu.edu [Department of Environmental and Molecular Toxicology, North Carolina State University, Raleigh, NC 27695 (United States)

    2011-10-15

    Highlights: Black-Right-Pointing-Pointer In the mayfly Centroptilum triangulifer, antioxidant enzymes catalase and superoxide dismutase were suppressed by dietary cadmium (Cd) exposures, but not dissolved exposures. Black-Right-Pointing-Pointer Dietary Cd reduced concentrations of active glutathione in whole insect homogenates. Black-Right-Pointing-Pointer These findings suggest that diet derived Cd is potentially more toxic than aqueous derived Cd in this mayfly, and may help explain the disconnection between laboratory and field data for aquatic insect responses to trace metal pollution. - Abstract: Aquatic organisms accumulate metals directly from water and from their diets. Exposure to metals is known to generate oxidative stress in living organisms and this stress may be ameliorated via activation of antioxidant enzymes and non-enzymatic antioxidants. To determine if antioxidant physiology is dependent on Cd exposure route in the mayfly Centroptilum triangulifer, we exposed larvae to environmentally relevant concentrations of Cd from isolated dissolved or dietary exposure routes to achieve comparable tissue concentrations. Dissolved Cd had no effect on the antioxidant enzymes examined. However, dietary Cd significantly suppressed catalase and superoxide dismutase activities, and decreased concentrations of the reduced (active) form of glutathione in C. triangulifer larvae. These findings suggest that dietary Cd is potentially more toxic than aqueously derived Cd in this mayfly. We further examined the effect of dietary Cd tissue loading rates on antioxidant enzyme suppression and found that absolute tissue load appeared more important than loading rate. These results may help explain why insects are routinely unresponsive to dissolved metal exposures in the laboratory, yet highly responsive to metal pollution in nature.

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

    OpenAIRE

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

    2015-01-01

    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 b...

  5. Finite Element Vibration and Dynamic Response Analysis of Engineering Structures

    Directory of Open Access Journals (Sweden)

    Jaroslav Mackerle

    2000-01-01

    Full Text Available This bibliography lists references to papers, conference proceedings, and theses/dissertations dealing with finite element vibration and dynamic response analysis of engineering structures that were published from 1994 to 1998. It contains 539 citations. The following types of structures are included: basic structural systems; ground structures; ocean and coastal structures; mobile structures; and containment structures.

  6. Finite element estimation of acoustical response functions in HID lamps

    Energy Technology Data Exchange (ETDEWEB)

    Baumann, Bernd; Wolff, Marcus [Department of Mechanical Engineering and Production, School of Engineering and Computer Science, Hamburg University of Applied Sciences, Berliner Tor 21, 20099 Hamburg (Germany); Hirsch, John; Antonis, Piet [Philips Lighting BV, Lightlabs, Mathildelaan 1, 5600 JM Eindhoven (Netherlands); Bhosle, Sounil [Universite de Toulouse (United States); Barrientos, Ricardo Valdivia, E-mail: bernd.baumann@haw-hamburg.d [National Nuclear Research Institute, Highway Mexico-Toluca s/n, La Marquesa, Ocoyoacac, CP 52750 (Mexico)

    2009-11-21

    High intensity discharge lamps can experience flickering and even destruction when operated at high frequency alternating current. The cause of these problems has been identified as acoustic resonances inside the lamp's arc tube. Here, a finite element approach for the calculation of the acoustic response function is described. The developed model does not include the plasma dynamics.

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

    Science.gov (United States)

    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.

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

    Science.gov (United States)

    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

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

    International Nuclear Information System (INIS)

    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

  10. Effect of Antioxidant Mineral Elements Supplementation in the Treatment of Hypertension in Albino Rats

    OpenAIRE

    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 blo...

  11. Deficiency of glutathione transferase zeta causes oxidative stress and activation of antioxidant response pathways.

    Science.gov (United States)

    Blackburn, Anneke C; Matthaei, Klaus I; Lim, Cindy; Taylor, Matthew C; Cappello, Jean Y; Hayes, John D; Anders, M W; Board, Philip G

    2006-02-01

    Glutathione S-transferase (GST) zeta (GSTZ1-1) plays a significant role in the catabolism of phenylalanine and tyrosine, and a deficiency of GSTZ1-1 results in the accumulation of maleylacetoacetate and its derivatives maleylacetone (MA) and succinylacetone. Induction of GST subunits was detected in the liver of Gstz1(-/-) mice by Western blotting with specific antisera and high-performance liquid chromatography analysis of glutathione affinity column-purified proteins. The greatest induction was observed in members of the mu class. Induction of NAD(P)H:quinone oxidoreductase 1 and the catalytic and modifier subunits of glutamate-cysteine ligase was also observed. Many of the enzymes that are induced in Gstz1(-/-) mice are regulated by antioxidant response elements that respond to oxidative stress via the Keap1/Nrf2 pathway. It is significant that diminished glutathione concentrations were also observed in the liver of Gstz1(-/-) mice, which supports the conclusion that under normal dietary conditions, the accumulation of electrophilic intermediates such as maleylacetoacetate and MA results in a high level of oxidative stress. Elevated GST activities in the livers of Gstz1(-/-) mice suggest that GSTZ1-1 deficiency may alter the metabolism of some drugs and xenobiotics. Gstz1(-/-) mice given acetaminophen demonstrated increased hepatotoxicity compared with wild-type mice. This toxicity may be attributed to the increased GST activity or the decreased hepatic concentrations of glutathione, or both. Patients with acquired deficiency of GSTZ1-1 caused by therapeutic exposure to dichloroacetic acid for the clinical treatment of lactic acidosis may be at increased risk of drug- and chemical-induced toxicity. PMID:16278372

  12. Plant responses to stresses: role of ascorbate peroxidase in the antioxidant protection

    Directory of Open Access Journals (Sweden)

    Andréia Caverzan

    2012-01-01

    Full Text Available When plants are exposed to stressful environmental conditions, the production of Reactive Oxygen Species (ROS increases and can cause significant damage to the cells. Antioxidant defenses, which can detoxify ROS, are present in plants. A major hydrogen peroxide detoxifying system in plant cells is the ascorbate-glutathione cycle, in which, ascorbate peroxidase (APX enzymes play a key role catalyzing the conversion of H2O2 into H2O, using ascorbate as a specific electron donor. Different APX isoforms are present in distinct subcellular compartments, such as chloroplasts, mitochondria, peroxisome, and cytosol. The expression of APX genes is regulated in response to biotic and abiotic stresses as well as during plant development. The APX responses are directly involved in the protection of plant cells against adverse environmental conditions. Furthermore, mutant plants APX genes showed alterations in growth, physiology and antioxidant metabolism revealing those enzymes involvement in the normal plant development.

  13. Study of antioxidant activity of sheep visceral protein hydrolysate: Optimization using response surface methodology

    OpenAIRE

    Meshginfar, Nasim; Sadeghi-Mahoonak, Alireza; Ziaiifar, Aman Mohammad; Ghorbani, Mohammad; Kashaninejad, Mahdi

    2014-01-01

    BACKGROUND The main objective of this experiment was optimal use of none edible protein source to increase nutritional value of production with high biological function, including antioxidant activity. METHODS Sheep visceral (stomach and intestine) was used as substrate. Response surface methodology (RSM) was used to optimize hydrolysis conditions for preparing protein hydrolysate from the sheep visceral, using alcalase 2.4 l enzyme. The investigated factors were temperature (43-52 °C), time ...

  14. Dose-response effects of gamma irradiation on colour and antioxidant activity of wild Malva neglecta

    OpenAIRE

    Pinela, José; Antonio, Amilcar L.; Barros, Lillian; Carvalho, Ana Maria; Oliveira, M.B.P.P.; Ferreira, Isabel C. F. R.

    2014-01-01

    Radiation processing technology has been used to improve food security, safety and quality. However there are a few reports in the literature on the effect of irradiation on bioactivity of herbs and medicinal plants [1]. Hence, the present work was undertaken to investigate the dose-response effects of gamma irradiation on the colour and antioxidant activity of wild Malva neglecta Wallr. In the north-eastern of Portugal, this annual herbaceous plant is traditionally eaten raw as leafy vegetab...

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

    OpenAIRE

    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 deter...

  16. Parallel finite element modeling of earthquake ground response and liquefaction

    Institute of Scientific and Technical Information of China (English)

    Jinchi Lu(陆金池); Jun Peng(彭军); Ahmed Elgamal; Zhaohui Yang(杨朝晖); Kincho H. Law

    2004-01-01

    Parallel computing is a promising approach to alleviate the computational demand in conducting large-scale finite element analyses. This paper presents a numerical modeling approach for earthquake ground response and liquefaction using the parallel nonlinear finite element program, ParCYCLIC, designed for distributed-memory message-passing parallel computer systems. In ParCYCLIC, finite elements are employed within an incremental plasticity, coupled solid-fluid formulation. A constitutive model calibrated by physical tests represents the salient characteristics of sand liquefaction and associated accumulation of shear deformations. Key elements of the computational strategy employed in ParCYCLIC include the development of a parallel sparse direct solver, the deployment of an automatic domain decomposer, and the use of the Multilevel Nested Dissection algorithm for ordering of the finite element nodes. Simulation results of centrifuge test models using ParCYCLIC are presented. Performance results from grid models and geotechnical simulations show that ParCYCLIC is efficiently scalable to a large number of processors.

  17. Herbicidal and antioxidant responses of transgenic rice overexpressing Myxococcus xanthus protoporphyrinogen oxidase.

    Science.gov (United States)

    Jung, Sunyo; Back, Kyoungwhan

    2005-05-01

    We analyzed the herbicidal and antioxidant defense responses of transgenic rice plants that overexpressed the Myxococcus xanthus protoporphyrinogen oxidase gene. Leaf squares of the wild-type incubated with oxyfluorfen were characterized by necrotic leaf lesions and increases in conductivity and malonyldialdehyde levels, whereas transgenic lines M4 and M7 did not show any change with up to 100 microM oxyfluorfen. The wild-type had decreased F(v)/F(m) and produced a high level of H(2)O(2) at 18 h after foliar application of oxyfluorfen, whereas transgenic lines M4 and M7 were unaffected. In response to oxyfluorfen, violaxanthin, beta-carotene, and chlorophylls (Chls) decreased in wild-type plants, whereas antheraxanthin and zeaxanthin increased. Only a slight decline in Chls was observed in transgenic lines at 48 h after oxyfluorfen treatment. Noticeable increases of cytosolic Cu/Zn-superoxide dismutase, peroxidase isozymes 1 and 2, and catalase were observed after at 48 h of oxyfluorfen treatment in the wild-type. Non-enzymatic antioxidants appeared to respond faster to oxyfluorfen-induced photodynamic stress than did enzymatic antioxidants. Protective responses for the detoxification of active oxygen species were induced to counteract photodynamic stress in oxyfluorfen-treated, wild-type plants. However, oxyfluorfen-treated, transgenic plants suffered less oxidative stress, confirming increased herbicidal resistance resulted from dual expression of M. xanthus Protox in chloroplasts and mitochondria. PMID:15890521

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

    Science.gov (United States)

    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

  19. Molecular mechanisms of plant response to ionising radiation. Exploration of the glucosinolate role in the anti-oxidative response

    International Nuclear Information System (INIS)

    Terrestrial organisms are exposed to low doses of ionising radiation from natural or anthropogenic sources. The major effects of the radiations are due to DNA deterioration and water radiolysis which generates an oxidative stress by free radical production. Plants constitute good models to study the effects of ionising radiations and the search of antioxidant molecules because of their important secondary metabolism. Thus this thesis, funded by the Brittany region, characterized the physiological and molecular response of the model plant Arabidopsis thaliana to low (10 Gy) and moderate (40 Gy) doses of ionising radiation, and was therefore interested in glucosinolates, characteristic compounds of the Brassicaceae family. The global proteomic and transcriptomic studies carried out on this model revealed (1) a common response for both doses dealing with the activation of DNA repair mechanisms, cell cycle regulation and protection of cellular structures; (2) an adjustment of the energetic metabolism and an activation of secondary compounds biosynthesis (i.e. glucosinolates and flavonoids) after the 10 Gy dose; (3) an induction of enzymatic control of ROS, the regulation of cellular components recycling and of programmed cell death after the 40 Gy dose. The potential anti-oxidative role of glucosinolates was then explored. The in vitro anti-oxidative power of some glucosinolates and their derivative products were demonstrated. Their modulating effects against irradiation-induced damages were then tested in vivo by simple experimental approaches. The importance of the glucosinolate level to give a positive or negative effect was demonstrated. (author)

  20. Spectral response of multi-element silicon detectors

    Energy Technology Data Exchange (ETDEWEB)

    Ludewigt, B.A.; Rossington, C.S.; Chapman, K. [Univ. of California, Berkeley, CA (United States)

    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.

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

    Science.gov (United States)

    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

  2. Antioxidant response of the brown algae Dictyota dichotoma epiphytized by the invasive red macroalgae Lophocladia lallemandii

    Institute of Scientific and Technical Information of China (English)

    Silvia Tejada; Antoni Sureda

    2014-01-01

    Objective: To evaluate the response of the brown alga Dictyota dichotoma (D. dichotoma) epiphytized by the red alga Lophocladia lallemandii in Mallorca coastal waters (Balearic Islands) by means of biomarker measures. Methods: Samples of epiphytized and non-epiphytized D. dichotoma were collected in Cala Morlanda (East Mallorca, Balearic Islands). Markers of lipid peroxidation and activities of antioxidant enzymes were measured in D. dichotoma. Results: Lipid peroxidation measured as malondialdehyde and all the antioxidant activities measured were significantly higher in the epiphytized brown algae when compared with the control algae. Conclusions:In conclusion, the invasive algae Lophocladia lallemandii seems to produce a more oxidized status in the epiphytized D. dichotoma and cellular damage that could induce increased mortality.

  3. Antioxidant response of the brown algae Dictyota dichotoma epiphytized by the invasive red macroalgae Lophocladia lallemandii

    Directory of Open Access Journals (Sweden)

    Silvia Tejada

    2014-05-01

    Full Text Available Objective: To evaluate the response of the brown alga Dictyota dichotoma (D. dichotoma epiphytized by the red alga Lophocladia lallemandii in Mallorca coastal waters (Balearic Islands by means of biomarker measures. Methods: Samples of epiphytized and non-epiphytized D. dichotoma were collected in Cala Morlanda (East Mallorca, Balearic Islands. Markers of lipid peroxidation and activities of antioxidant enzymes were measured in D. dichotoma. Results: Lipid peroxidation measured as malondialdehyde and all the antioxidant activities measured were significantly higher in the epiphytized brown algae when compared with the control algae. Conclusions: In conclusion, the invasive algae Lophocladia lallemandii seems to produce a more oxidized status in the epiphytized D. dichotoma and cellular damage that could induce increased mortality.

  4. Response of enzymatic and non-enzymatic antioxidant defense systems of Polygonum hydropiper to Mn stress

    Institute of Scientific and Technical Information of China (English)

    杨贤均; 邓冬梅; 刘可慧; 于方明

    2016-01-01

    The response of enzyme and non-enzymatic antioxidants of Mn hyperaccumuator,Polygonum hydropiper (P. hydropiper), to Mn stress was studied using hydroponics culture experiments to explore the mechanism of Mn tolerance in this species. Results showed that both chlorophyll and carotenoid contents significantly (p<0.05) decreased with increasing Mn treatment levels (0, 0.5, 1, 2, 4, and 8 mg/L) in hydroponics. The concentrations of malondialdehyde (MDA) and hydrogen peroxide (H2O2) in the root and shoot ofP. hydropiper were accumulated under Mn stress. Meanwhile, the anti-oxidative functions of several important enzymes, including superoxide dismutase (SOD), catalase (CAT), ascorbate peroxidase (APX) and peroxidase (POD) in plants were stimulated by Mn spike in leaves and roots, especially at low Mn stress; while sulfhydryl group (—SH) and glutathion (GSH) were likely involved in Mn detoxification ofP. hydropiper under high Mn stress.

  5. Design Process for Integrated Concepts with Responsive Building Elements

    DEFF Research Database (Denmark)

    Aa, Van der A.; Heiselberg, Per

    2008-01-01

    An integrated building concept is a prerequisite to come to an energy efficient building with a good and healthy IAQ indoor comfort. A design process that defines the targets and boundary conditions in the very first stage of the design and guarantees them until the building is finished and used...... is needed. The hard question is however: how to make the right choice of the combination of individual measures from building components and building services elements. Within the framework of IEA-ECBCS Annex 44 research has been conducted about the design process for integrated building concepts...... with responsive building elements. The (Dutch) Toolkit Sustainable Residential Buildings is one of the examples of tools for an integrated design process....

  6. Sulforaphane ameliorates the insulin responsiveness and the lipid profile but does not alter the antioxidant response in diabetic rats.

    Science.gov (United States)

    de Souza, Carolina Guerini; da Motta, Leonardo Lisbôa; de Assis, Adriano Martimbianco; Rech, Anderson; Bruch, Ricardo; Klamt, Fábio; Souza, Diogo Onofre

    2016-04-20

    Diabetes is one of the most prevalent chronic non-communicable diseases and is characterized by hyperglycemia and increased oxidative stress. These two alterations are also responsible for the main diabetic complications: cardiovascular disease, retinopathy, nephropathy and peripheral neuropathy. Diabetes progression is governed by pancreatic β-cell failure, and recent studies showed that sulforaphane (SFN) might be able to prevent this change, preserving insulin production. Consequently, our goal was to test the effects of SFN on metabolic parameters related to diabetic complications and antioxidant defenses (superoxide dismutase, catalase and sulfhydryl groups) in the pancreas, liver and kidney of non-diabetic and diabetic rats. Male Wistar rats were treated with water or 0.5 mg kg(-1) SFN i.p. for 21 days after diabetes induction. In diabetic animals treated with SFN, the serum levels of total cholesterol, non-HDL cholesterol and triacylglycerols were similar to those of non-diabetic animals, and the insulin responsiveness was higher than that of the diabetic animals that did not receive the compound. No effect of SFN on the superoxide dismutase and catalase activity or sulfhydryl groups was observed in the pancreas, liver or kidney of the treated animals. We conclude that SFN ameliorates some features of clinical diabetic complications particularly the lipid profile and insulin responsiveness, but it does not modulate the antioxidant response induced by superoxide dismutase, catalase and sulfhydryl groups in the evaluated organs. PMID:27025193

  7. Interactions of arsenic and phenanthrene on their uptake and antioxidative response in Pteris vittata L

    Energy Technology Data Exchange (ETDEWEB)

    Sun Lu [Beijing Key Lab of Industrial Land Contamination and Remediation, Institute of Geographical Sciences and Natural Resources Research, Chinese Academy of Sciences (CAS), Beijing 100101 (China); Graduate University of the Chinese Academy of Sciences, Beijing 100049 (China); Yan Xiulan [Beijing Key Lab of Industrial Land Contamination and Remediation, Institute of Geographical Sciences and Natural Resources Research, Chinese Academy of Sciences (CAS), Beijing 100101 (China); Liao Xiaoyong, E-mail: liaoxy@igsnrr.ac.cn [Beijing Key Lab of Industrial Land Contamination and Remediation, Institute of Geographical Sciences and Natural Resources Research, Chinese Academy of Sciences (CAS), Beijing 100101 (China); Wen Yi; Chong Zhongyi; Liang Tao [Beijing Key Lab of Industrial Land Contamination and Remediation, Institute of Geographical Sciences and Natural Resources Research, Chinese Academy of Sciences (CAS), Beijing 100101 (China)

    2011-12-15

    The interactions of arsenic and phenanthrene on plant uptake and antioxidative response of Pteris vitatta L. were studied hydroponically. The combination of arsenic and phenanthrene decreased arsenic contents in fronds by 30-51%, whereas increased arsenic concentrations 1.2-1.6 times in roots, demonstrating the suppression of arsenic translocation compared to the corresponding treatment without phenanthrene. Under the co-exposure, As(III) concentrations in fronds deceased by 12-73%, and at higher arsenic exposure level ({>=}10 mg/L), As(V) in fronds and As(III) in roots increased compared to the single arsenic treatment. Arsenic exposure elevated phenanthrene concentrations in root by 39-164%. The co-existence of arsenic and phenanthrene had little impact on plant arsenic accumulation, although synergistic effect on antioxidants was observed, suggesting the special physiological process of P. vitatta in the co-exposure and application potential of P. vitatta in phytoremediation of arsenic and PAHs co-contamination. - Highlights: > Pteris vitatta L. show tolerance to the arsenic and phenanthrene co-exposure. > P. vitatta efficiently accumulate arsenic and simultaneously enhance phenanthrene dissipation. > Phenanthrene suppresses arsenic translocation from roots to fronds. > Phenanthrene causes As(III) elevation in roots while reduction in fronds. > Synergistic effect potentiates the toxicity and antioxidants in plant. - Pteris vitatta L. not only efficiently accumulate arsenic but also enhance phenanthrene dissipation under the arsenic and phenanthrene co-exposure.

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

    Science.gov (United States)

    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.

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

    Directory of Open Access Journals (Sweden)

    Anna Wyrwicka

    Full Text Available 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.

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

    Science.gov (United States)

    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

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

    Science.gov (United States)

    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

  12. Optimization of Ultrasound Assisted Extraction of Antioxidant Compounds from Marjoram (Origanum majorana L.) Using Response Surface Methodology

    OpenAIRE

    Hossain, Mohammad; Brunton, Nigel; Patras, Ankit; Tiwari, Brijesh; O Donnell, C.; Martin-Diana, Ana Belen; Barry-Ryan, Catherine

    2012-01-01

    The present study optimized the ultrasound assisted extraction (UAE) conditions to maximize the antioxidant activity [Ferric ion Reducing Antioxidant Power (FRAP)], total phenol content (TP) and content of individual polyphenols of extracts from marjoram. Optimal conditions with regard to amplitude of sonication (24.4–61.0 μm) and extraction temperature (15–35 °C) and extraction time (5–15 min) were identified using response surface methodology (RSM). The results showed that the combined trea...

  13. Evaluation of the antioxidant activity of Coreopsis tinctoria Nuff. and optimisation of isolation by response surface methodology

    OpenAIRE

    Lan Shumin; Lin Jingming; Zheng Ni

    2014-01-01

    The aim of the present study was to determine the antioxidant activity of Coreopsis tinctoria flowering tops (CTFT). Studies were conducted to obtain suitable extraction conditions for chlorogenic acid, quercetin, luteolin, apigenin and kaempferol, which were identified and quantified by HPLC. Response surface methodology was employed to optimise the ultrasound-assisted extraction conditions, including extraction time, ethanol concentration and liquid-solid ratio. The antioxidant activity of ...

  14. Optimisation of Ultrasound-Assisted Extraction Conditions for Phenolic Content and Antioxidant Capacity from Euphorbia tirucalli Using Response Surface Methodology

    OpenAIRE

    Quan V. Vuong; Chloe D. Goldsmith; Trung Thanh Dang; Van Tang Nguyen; Deep Jyoti Bhuyan; Elham Sadeqzadeh; Scarlett, Christopher J.; Bowyer, Michael C.

    2014-01-01

    Euphorbia tirucalli (E. tirucalli) is now widely distributed around the world and is well known as a source of traditional medicine in many countries. This study aimed to utilise response surface methodology (RSM) to optimise ultrasonic-assisted extraction (UAE) conditions for total phenolic compounds (TPC) and antioxidant capacity from E. tirucalli leaf. The results showed that ultrasonic temperature, time and power effected TPC and antioxidant capacity; however, the effects varied. Ultrason...

  15. Trace elements and antioxidants in Astragalus onobrychis L. var. chlorocarpus (Griseb. S. Kožuharov et D.K. Pavlova

    Directory of Open Access Journals (Sweden)

    Miladinović Dragoljub L.

    2011-01-01

    Full Text Available Leaves of growing-wild species Astragalus onobrychis L. var. chlorocarpus (Griseb. S. Kožuharov et D. K. Pavlova were collected during the different stages of growth and analyzed for iron (Fe, copper (Cu, zinc (Zn, manganese (Mn, soluble proteins, reduced glutathione (GSH, total flavonoid and total carotenoid contents. Iron, copper and manganese have shown similar seasonal pattern, increasing of metal content in leaves during the vegetative period. The highest values of the examined elements were in seed forming stage, except zinc. The highest value of this element was recorded in initial stage of vegetation. Antioxidant compounds have the highest values in blooming stage of vegetation. The results from the present study suggest that researched plant species represent a good source of trace elements and antioxidant compounds.

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

    Science.gov (United States)

    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.

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

    Science.gov (United States)

    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

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

    Science.gov (United States)

    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.

  19. The Marburg Virus VP24 Protein Interacts with Keap1 to Activate the Cytoprotective Antioxidant Response Pathway

    Directory of Open Access Journals (Sweden)

    Megan R. Edwards

    2014-03-01

    Full Text Available Kelch-like ECH-associated protein 1 (Keap1 is a ubiquitin E3 ligase specificity factor that targets transcription factor nuclear factor (erythroid-derived 2-like 2 (Nrf2 for ubiquitination and degradation. Disrupting Keap1-Nrf2 interaction stabilizes Nrf2, resulting in Nrf2 nuclear accumulation, binding to antioxidant response elements (AREs, and transcription of cytoprotective genes. Marburg virus (MARV is a zoonotic pathogen that likely uses bats as reservoir hosts. We demonstrate that MARV protein VP24 (mVP24 binds the Kelch domain of either human or bat Keap1. This binding is of high affinity and 1:1 stoichiometry and activates Nrf2. Modeling based on the Zaire ebolavirus (EBOV VP24 (eVP24 structure identified in mVP24 an acidic loop (K-loop critical for Keap1 interaction. Transfer of the K-loop to eVP24, which otherwise does not bind Keap1, confers Keap1 binding and Nrf2 activation, and infection by MARV, but not EBOV, activates ARE gene expression. Therefore, MARV targets Keap1 to activate Nrf2-induced cytoprotective responses during infection.

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

    Science.gov (United States)

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

    Science.gov (United States)

    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

  2. Growth, photosynthesis, and antioxidant responses of Vigna unguiculata L. treated with hydrogen peroxide

    Directory of Open Access Journals (Sweden)

    Syed Aiman Hasan

    2016-12-01

    Full Text Available Cowpea (Vigna unguiculata L. is an important legume well grown in semiarid and arid environment. Hydrogen peroxide solutions (0.1, 0.5, 1.0, and 1.5 mM have been used to optimize growth and photosynthetic performance of cowpea plant at two growth stages [30 and 45 DAS (days of sowing]. Foliar application of H2O2 at 0.5 > 1.0 mM solution at 29 DAS optimally promoted the photosynthetic attributes [leaf chlorophyll content, net photosynthetic rate (PN, water use efficiency, and maximum quantum yield of PSII (Fv/Fm] and growth performance [root and shoot length; fresh and dry weight] of plants where the responses were more significant at the later growth stage. It was favored by activity of enzymes as carbonic anhydrase [CA; E.C. 4.2.1.1] and nitrate reductase [NR, E.C. 1.6.6.1] and those of antioxidant enzymes viz. peroxidase [POX; EC 1.11.1.7], catalase [CAT; EC 1.11.1.6], and superoxide dismutase [SOD; EC 1.15.1.1] and leaf proline content. Strengthened root system and antioxidant activity, particularly leaf proline level appeared to be the key factor for efficient photosynthesis and growth responses.

  3. Optimization of ultrasound-assisted extraction of antioxidant compounds from Tunisian Zizyphus lotus fruits using response surface methodology.

    Science.gov (United States)

    Hammi, Khaoula Mkadmini; Jdey, Ahmed; Abdelly, Chedly; Majdoub, Hatem; Ksouri, Riadh

    2015-10-01

    The optimization of antioxidant extraction conditions from a ripe edible fruits of Zizyphus lotus (L.) with an ultrasound-assisted system was achieved by response surface methodology. The central composite rotatable design was employed for optimization of extraction parameters in terms of total phenolic content and antioxidant activities using 2,2-diphenyl-1-picrylhydrazyl radical scavenging activity and phosphomolybdenum assay. The optimum operating conditions for extraction were as follows: ethanol concentration, 50%; extraction time, 25 min; extraction temperature, 63°C and ratio of solvent to solid, 67 mL/g. Under these conditions, the obtained extract exhibited a high content of phenolic compounds (40.782 mg gallic acid equivalents/g dry matter) with significant antioxidant properties (the total antioxidant activity was 75.981 mg gallic acid equivalents/g dry matter and the 2,2-diphenyl-1-picrylhydrazyl radical scavenging activity was 0.289 mg/mL). PMID:25872429

  4. Evaluation of the Antioxidant Activity of Coreopsis Tinctoria Nuff. and Optimisation of Isolation by Response Surface Methodology

    Directory of Open Access Journals (Sweden)

    Lan Shumin

    2014-09-01

    Full Text Available The aim of the present study was to determine the antioxidant activity of Coreopsis tinctoria flowering tops (CTFT. Studies were conducted to obtain suitable extraction conditions for chlorogenic acid, quercetin, luteolin, apigenin and kaempferol, which were identified and quantified by HPLC. Response surface methodology was employed to optimise the ultrasound-assisted extraction conditions including extraction time, ethanol concentration and liquid-solid ratio. The antioxidant activity of the extracts was analysed using various antioxidant models, such as DPPH, ABTS and hydroxyl radical scavenging assay. CTFT extracted for 15.0 min with ethanol at a concentration of 60.4 % and with liquidsolid ratio 27.5:1 possessed a considerable amounts of total flavonoids and polyphenols (18.9 %. This extract showed higher scavenging activity of ABTS and hydroxyl radical activity than rutin, however not in the DPPH test. We may assume that CTFT possess antioxidant and free radical scavenging potentials.

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

    Science.gov (United States)

    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

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

    Science.gov (United States)

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

    Science.gov (United States)

    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.

  8. Response of Daphnia's antioxidant system to spatial heterogeneity in Cyanobacteria concentrations in a lowland reservoir.

    Directory of Open Access Journals (Sweden)

    Adrianna Wojtal-Frankiewicz

    Full Text Available Many species and clones of Daphnia inhabit ecosystems with permanent algal blooms, and they can develop tolerance to cyanobacterial toxins. In the current study, we examined the spatial differences in the response of Daphnia longispina to the toxic Microcystis aeruginosa in a lowland eutrophic dam reservoir between June (before blooms and September (during blooms. The reservoir showed a distinct spatial pattern in cyanobacteria abundance resulting from the wind direction: the station closest to the dam was characterised by persistently high Microcystis biomass, whereas the upstream stations had a significantly lower biomass of Microcystis. Microcystin concentrations were closely correlated with the cyanobacteria abundance (r = 0.93. The density of daphniids did not differ among the stations. The main objective of this study was to investigate how the distribution of toxic Microcystis blooms affects the antioxidant system of Daphnia. We examined catalase (CAT activity, the level of the low molecular weight antioxidant glutathione (GSH, glutathione S-transferase (GST activity and oxidative stress parameters, such as lipid peroxidation (LPO. We found that the higher the abundance (and toxicity of the cyanobacteria, the lower the values of the antioxidant parameters. The CAT activity and LPO level were always significantly lower at the station with the highest M. aeruginosa biomass, which indicated the low oxidative stress of D. longispina at the site with the potentially high toxic thread. However, the low concentration of GSH and the highest activity of GST indicated the occurrence of detoxification processes at this site. These results demonstrate that daphniids that have coexisted with a high biomass of toxic cyanobacteria have effective mechanisms that protect them against the toxic effects of microcystins. We also conclude that Daphnia's resistance capacity to Microcystis toxins may differ within an ecosystem, depending on the bloom

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

    Science.gov (United States)

    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.

  10. Photosynthesis and antioxidant response to winter rapeseed (brassica napus l.) as affected by boron

    International Nuclear Information System (INIS)

    Effect of boron on photosynthesis and antioxidant response to rapeseed yield was studied by the field experimentation along with plant analysis during the winter season of 2010 and 2011. The field experimentation was conducted by split plot design with three replications consisting of two factors such as i) two rapeseed cultivars (viz. Xiangzayou 1613 and 09-13581613), assigned in main plots and ii) five boron levels (viz. 0, 4.5, 9.0, 13.5 and 18.0 kgha-1) imposed in the sub-plots. The rate of photosynthesis increased with increasing boron level upto 9.0 kgha-1 with simultaneous increase in photosynthetically active radiation, rate of transpiration and stomatal conductance and decrease in intercellular CO/sun 2/ concentration in both cultivars, while reverse trend was shown with further increase of B concentration. B @ 9.0 kgha- improved the activities of antioxidant protective enzyme of SOD and POD and decreased the accumulation of MDA content in the both cultivars. Dry matter translocation increased with increasing B level upto 9.0 kgha-1 that resulted the highest seed yield and harvest index of rapeseed in both cultivars. Thus, B @ 9 kgha-1 is sufficient for rapeseed cultivation under the subtropical environmental condition of the Southern China. Brassica napus. (author)

  11. Metallothionein induction and antioxidative responses in the estuarine polychaeta Capitella capitata (Capitellidae)

    Institute of Scientific and Technical Information of China (English)

    Suriya J; S Bharathiraja; V Sekar; R Rajasekaran

    2012-01-01

    Objective: To evaluate the antioxidant response induced by copper (Cu) exposure inCapitella capitata. The capacity of Cu bioaccumulation was also evaluated through the metal quantification. Methods: Worms were exposed to different concentrations of Cu 50, 100, and 200 μg/L for 7, 14 and 21 days respectively. In all the assays, control groups were run in parallel, employing only saline water (10%). The concentrations of Cu in the digested acidic solutions of worms were determined by using the inductively coupled plasma-Optical emission spectrophotometry. The total protein content and other anti oxidant enzyme activities such as superoxide dismutase (SOD), catalase (CAT) and glutathione S-transferase (GST) were recorded for the experiment period. Results: Bioaccumulation of Cu metals in polychaetes was increased parallel to exposure time. A peak concentration (197.30±12.32 μg/g) of metallothioneins (MTs) was registered at 14th day of 100 μg/L group compared to control group (37.29 μg/g). Catalase activities (CAT) in Cu treated-worms were increased significantly (P<0.05) after 7 and 14 days of exposure. The concentration of Cu had significant (P<0.05) influences on the activity of SOD. The same physiological activity was recorded in GST evaluation. Conclusions: These results of biochemical variables in C. capitata suggest us a useful model species for monitoring of environmental disturbance by heavy metal pollution. Antioxidant defenses were confirmed as sensitive biomarkers for metal stress in polychaete worms.

  12. Optimization of pancreatic lipase inhibitory and antioxidant activities of Ilex paraguariensis by using response surface methodology.

    Science.gov (United States)

    Oh, Kyung-Eon; Shin, Hyeji; Jeon, Young Ho; Jo, Yang Hee; Lee, Mi Kyeong; Lee, Ken S; Park, Byoungduck; Lee, Ki Yong

    2016-07-01

    Response surface methodology (RSM) using a Box-Behnken design was used to optimize the extraction conditions for obtaining pancreatic lipase inhibitory and antioxidant principles from Ilex paraguariensis leaves. Three influencing factors: extraction time (min), the liquid-solid ratio, and ethanol concentration (%, v/v) were investigated in the ultrasonic extraction process. Optimization of the extraction conditions to obtain a product with minimum PL activity, maximum antioxidant activity, and maximum yield was performed using RSM by focusing on the three target influencing factors. The optimum conditions were established as the ethanol concentration (54.8 %), liquid-solid ratio (35.4), and extraction time (70.0 min). Under these conditions, the 2,2-diphenyl-1-picrylhydrazyl scavenging activity, PL activity, extraction yield were 59.3 ± 3.5, 35.3 ± 3.0, and 34.4 ± 0.4 %, respectively, similar to the theoretical predicted values of 59.7, 35.2, and 34.3 %, respectively. PMID:27277165

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

    Science.gov (United States)

    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

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

    Directory of Open Access Journals (Sweden)

    Ignacio Jofré

    2016-01-01

    Full Text Available 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.

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

    Science.gov (United States)

    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)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 (pstress 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. PMID:24580822

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

    Science.gov (United States)

    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.

  17. Flavonoids Extraction from Taraxacum officinale (Dandelion: Optimisation Using Response Surface Methodology and Antioxidant Activity

    Directory of Open Access Journals (Sweden)

    Zongxi Sun

    2014-01-01

    Full Text Available The Box-Behnken design combined with response surface method was employed to optimize ultrasonic-assisted extraction of flavonoids from Taraxacum officinale. The optimized results showed that the highest extraction yield with ultrasonic-assisted extraction could reach 2.62% using 39.6% (v/v ethanol and 59.5 : 1 (mL/g liquid-solid ratio for 43.8 min. The crude extract was then purified by HPD-100 macroporous adsorption resin, and the flavonoids content in the purified extract increased to 54.7%. The antioxidant activity of the purified flavonoids was evaluated in vitro by scavenging capacity of ABTS or DPPH, β-carotene bleaching, and FTC test. The knowledge obtained from this study should be useful to further develop and apply this plant resource.

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

    Science.gov (United States)

    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

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

    Directory of Open Access Journals (Sweden)

    Alice Dassano

    2014-01-01

    Full Text Available 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.

  20. The antioxidant response of the liver of male Swiss mice raised on a AIN 93 or commercial diet

    Directory of Open Access Journals (Sweden)

    Caetano Aline C

    2013-01-01

    Full Text Available Abstract Background Reactive oxygen species (ROS are formed under natural physiological conditions and are thought to play an important role in many human diseases. A wide range of antioxidants are involved in cellular defense mechanisms against ROS, which can be generated in excess during stressful conditions, these include enzymes and non-enzymatic antioxidants. The aim of this study was to evaluate the antioxidant responses of mice to two diets control, commercial and the purified AIN 93 diet, commonly used in experiments with rodents. Results Malondialdehyde (MDA and hydrogen peroxide (H2O2 concentrations and superoxide dismutase (SOD and glutathione reductase (GR activities determined in the liver were lower in the group of mice fed with the AIN 93 diet, while catalase (CAT activity was higher in the same group, when compared to the group fed on the commercial diet. Liver glutathione peroxidase (GSH-Px activity was similar in the groups fed on either AIN 93 or the commercial diets. Two SOD isoforms, Mn-SODII and a Cu/Zn-SODV, were specifically reduced in the liver of the AIN 93 diet fed animals. Conclusions The clear differences in antioxidant responses observed in the livers of mice fed on the two diets suggest that the macro- and micro-nutrient components with antioxidant properties, including vitamin E, can promote changes in the activity of enzymes involved in the removal of the ROS generated by cell metabolism.

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

    Science.gov (United States)

    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.

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

    Science.gov (United States)

    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.

  3. Optimization of extraction time and temperature on antioxidant activity of Schizophyllum commune aqueous extract using response surface methodology

    OpenAIRE

    Yim, Hip Seng; Chye, Fook Yee; Rao, Vigneswara; Low, Jia Yin; Matanjun, Patricia; How, Siew Eng; Ho, Chun Wai

    2011-01-01

    Central composite design of response surface methodology (RSM) was employed to optimize the extraction time (X1: 99.5–290.5 min) and temperature (X2: 30.1–54.9 °C) of Schizophyllum commune aqueous extract with high antioxidant activities and total phenolic content (TPC). Results indicated that the data were adequately fitted into four second-order polynomial models. The extraction time and temperature were found to have significant linear, quadratic and interaction effects on antioxidant acti...

  4. Antioxidative Responses and Metal Accumulation in Invasive Plant Species Growing on Mine Tailings in Zanjan, Iran

    Institute of Scientific and Technical Information of China (English)

    M. M. A. BOO JAR; Z. TAVAKKOLI

    2011-01-01

    Tailings of a Pb and Zn mine as a metal-contaminated area (Zone 1) with two pioneer plant species,Peganum harmala and Zygophyllum fabago,were investigated and compared with a non-contaminated area (Zone 2) in the vicinity.Total concentrations of Pb,Zn,and Cu in the soil of Zone 1 were 1 416,2217,and 426 mg kg-1,respectively,and all exceeded their ranges in the normal soils.The soil pH was in the neutral range and most of the physical and chemical characteristics of the soils from both zones were almost similar.The species Z.fabago accumulated higher Cu and Zn in its aerial part and roots than the normal plants.On the other.hand,their concentrations did not reach the criteria that the species could be considered as a metal hyperaccumulator.The species P.harmala did not absorb metals in its roots; accordingly,the accumulation factor values of these metals were lower than 1.The contents of chlorophyll,biomass,malondialdehyde,and dityrosine in these two species did not vary significantly between the two zones studied.In Zone 1,leaf vacuoles of Z.fabago stored 35.6% and 43.2% of the total leaf Cu and Zn,respectively.However,in this species,the levels of phytochelatins (PCs) and glutathione (GSH) and antioxidant enzyme activities were significantly higher in Zone 1 than in Zone 2.In conclusion,metal exclusion in P.harmala and metal accumulation in Z.fabago were the basic strategies in the two studied pioneer species growing on the metal-contaminated zone.In response to metal stress,elevation in antioxidant enzyme activities,increases in the PCs and GSH levels in the aerial parts,and metal storage within vacuoles counteracted each other in the invasion mechanism of Z.fabago.

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

    Science.gov (United States)

    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

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

    Science.gov (United States)

    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

  7. OPTIMIZATION OF EXTRACTION OF PHENOLIC ANTIOXIDANTS FROM TEA (CAMELLIA SINENSIS L. FRUIT PEEL BIOMASS USING RESPONSE SURFACE METHODOLOGY

    Directory of Open Access Journals (Sweden)

    Ping Xu,

    2012-04-01

    Full Text Available Tea (Camellia sinensis L. fruit peel, the main byproduct during the manufacture of tea seed oil, was used as raw material for the recovery of phenolic antioxidants. The effect of ethanol concentration, extraction time, and extraction temperature on total phenolic content (TPC and ferric-reducing antioxidant power (FRAP of the extracts from tea fruit peel was investigated. The maximum predicted TPC (47.5 mg GAE/g dry peel was obtained under the optimum recovery conditions (43% ethanol, 60°C, and 33 min given by using response surface methodology (RSM. A high correlation (R2 = 0.929, p < 0.01 between TPC and FRAP value was identified by linear regression analysis. Furthermore, gallocatechin (GC and epigallocatechin (EGC were found to be the major individual catechins in the extracts from tea fruit peel. Ethanol/aqueous extraction has been presented as an effective method for the recovery of phenolic antioxidants from tea fruit peel.

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

    Science.gov (United States)

    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

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

    Science.gov (United States)

    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

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

    Science.gov (United States)

    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

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

    Science.gov (United States)

    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

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

    International Nuclear Information System (INIS)

    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. -- Highlights: •Pinna nobilis is very sensitive to the human activities. •Anthropogenic pressure induces an antioxidant adaptation to the stressful situation. •Increased capability to generate reactive oxygen species in impacted areas. -- Pinna nobilis responds to the anthropogenic activity with an antioxidant adaptation to the increased capability to generate reactive oxygen species

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

    Directory of Open Access Journals (Sweden)

    Dong-Ping Xu

    2015-12-01

    Full Text Available 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.

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

    Science.gov (United States)

    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.

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

    Science.gov (United States)

    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.

  16. Short term supplementation of dietary antioxidants selectively regulates the inflammatory responses during early cutaneous wound healing in diabetic mice

    Directory of Open Access Journals (Sweden)

    Park Na-Young

    2011-11-01

    Full Text Available Abstract Background Diabetic foot ulcers are serious complications for diabetic patients, yet the precise mechanism that underlines the treatment of these diabetic complications remains unclear. We hypothesized that dietary antioxidant supplementation with vitamin C, combined either with vitamin E or with vitamin E and NAC, improves delayed wound healing through modulation of blood glucose levels, oxidative stress, and inflammatory response. Methods Diabetes was induced by administration of alloxan monohydrate. Mice were divided into 4 groups; CON (non-diabetic control mice fed AIN 93 G purified rodent diet, DM (diabetic mice fed AIN 93 G purified rodent diet, VCE (diabetic mice fed 0.5% vitamin C and 0.5% vitamin E supplemented diet, and Comb (diabetic mice fed 0.5% vitamin C, 0.5% vitamin E, and 2.5% NAC supplemented diet. After 10 days of dietary antioxidant supplementation, cutaneous full-thickness excisional wounds were performed, and the rate of wound closure was examined. TBARS as lipid peroxidation products and vitamin E levels were measured in the liver. Expression levels of oxidative stress and inflammatory response related proteins were measured in the cutaneous wound site. Results Dietary antioxidant supplementation improved blood glucose levels and wound closure rate and increased liver vitamin E, but not liver TBARS levels in the diabetic mice as compared to those of the CON. In addition, dietary antioxidant supplementation modulated the expression levels of pIκBα, HO-1, CuZnSOD, iNOS and COX-2 proteins in the diabetic mice. Conclusions These findings demonstrated that delayed wound healing is associated with an inflammatory response induced by hyperglycaemia, and suggests that dietary antioxidant supplementation may have beneficial effects on wound healing through selective modulation of blood glucose levels, oxidative stress, and inflammatory response.

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

    Science.gov (United States)

    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

  18. Nrf2-ARE通路在缺血后处理和吡那地尔后处理减轻大鼠离体心脏缺血再灌注损伤中的作用%Role of nuclear factor-E2 related factor 2-antioxidant response element pathway in cardio-protection by ischemic or pinacidil postconditioning against ischemia-reperfusion injury in isolated rat hearts

    Institute of Scientific and Technical Information of China (English)

    王海英; 杨义辉; 喻田; 刘兴奎

    2012-01-01

    目的 探讨核转录因子NF-E2相关因子2(Nrf2)-抗氧化反应元件(ARE)通路在缺血后处理和吡那地尔后处理减轻大鼠离体心脏缺血再灌注损伤中的作用.方法 健康雄性SD大鼠,体重200~250 g,4~5月龄,采用Langendorff灌注装置建立离体心脏灌注模型,取模型制备成功的心脏56个,采用随机数字表法,将其随机分为7组(n=8):正常对照组(C组)、缺血再灌注组(I/R组)、缺血后处理组(IP组)和不同浓度的吡那地尔后处理组(PP1组、PP2组、PP3组、PP4组).平衡灌注20min后,C组继续灌注100 min;I/R组停止灌注40 min,复灌60min;IP组停止灌注40 min,于再灌注开始给予6次间隔灌注10 s停止灌注10 s,复灌58 min;PP1组、PP2组、PP3组、PP4组停止灌注40 min,于再灌注开始时灌注含5、10、30、50 μmol/L吡那地尔的K-H液5min,继续灌注55 min.于平衡灌注末及复灌结束时测定左室发展压(LVDP)和左室舒张期末压(LVEDP);于复灌结束时取左心室心肌,分别采用RT-PCR法和Western blot法检测心肌Nrf2、醌氧化还原酶1(NQO1)、超氧化物歧化酶1(SOD1)及血红素加氧酶1(HO-1)的mRNA及蛋白表达水平.结果 与C组比较,其余各组Nrf2、NQO1、SOD1及HO-1的mRNA和蛋白表达均上调,I/R组、PP1组和PP2组复灌结束时LVDP降低,LVEDP升高(P<0.05).与I/R组比较,IP组、PP3组和PP4组Nrf2、NQO1、SODI及HO-1的mRNA和蛋白表达均上调,IP组、PP1组、PP2组、PP3组和PP4组复灌结束时LVDP升高,LVEDP降低(P<0.05).结论 缺血后处理和吡那地尔后处理可通过激活Nrf2-ARE通路减轻大鼠心肌缺血再灌注损伤.%Objective To evaluate the role of nuclear factor-E2 related factor 2 (Nrf2)-antioxidant response element (ARE) pathway in cardio-protection by ischemic or pinacidil postconditioning ( IP,PP) against ischemia-reperfusion (I/R) injury in isolated rat hearts.Methods Fifty-six male SD rats of both sexes weighing 200-250 g were anesthetized with

  19. Effect of antioxidant supplementation on insulin sensitivity in response to endurance exercise training

    DEFF Research Database (Denmark)

    Yfanti, Christina; Nielsen, Anders R; Åkerström, Thorbjörn;

    2011-01-01

    . To assess the effect of antioxidant supplementation during endurance training on insulin-stimulated glucose uptake, twenty-one young healthy (age 29±1 y; BMI 25±3 Kg m(-2)) men were randomly assigned into either an antioxidant (AO; 500 mg vitamin C and 400 IU vitamin E (a-tocopherol) daily) or a placebo (PL...

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

    Science.gov (United States)

    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

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

    Directory of Open Access Journals (Sweden)

    Amit Kumar Sinha

    Full Text Available 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

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

    Science.gov (United States)

    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

  3. High salt induced oxidative damage and antioxidant response in tomato grafted on tobacco

    Directory of Open Access Journals (Sweden)

    Özlem Darcansoy İşeri

    2015-06-01

    Full Text Available One of the major limitations on agricultural development in many countries is the high salinity of the groundwater used in irrigation. Grafted plants may exhibit phenotypic variations from scion and rootstock plants in terms of abiotic stress tolerance, and be a method for improvement of tolerance in agricultural practices. The aim of the present study was to investigate response of Solanum lycopersicum L. ('Elaziğ' grafted on Nicotiana tabacum L. ('Samsun' and Nicotiana rustica L. ('Hasankeyf', namely "Tomacco" plant (patent nr TR-2008-05391-B, to 10-d high NaCl irrigation. Physical development, chlorophyll a and b, total chlorophyll, total carotenoid, and anthocyanin levels were evaluated. Proline, lipid peroxidation, and electrolyte leakage levels were assayed in roots and leaves together with ascorbate peroxidase (APX and catalase (CAT activities. Considering alterations in chlorophyll contents, proline, malondialdehyde (MDA, and conductivity levels, and antioxidant enzyme activity levels scion and self-grafted plants seem to be more affected by salt treatments than tobacco and rootstock grafted plants. Tobacco roots seem to have better adaptive responses against salt stress in comparison to tomato as supported by changes in proline, APX, and CAT levels. Self-grafting experiments further supported grafting tomato onto tobacco rootstocks enhanced salt tolerance and adaptive response of scions and these changes seem to be dependent on rootstock rather than graft-induced changes. In conclusion, we demonstrated that previously defined graft unions of tomato on tobacco, which have increased fruit yield, had also enhanced tolerance to high salt stress and a promising technique for the cultivation of more salt tolerant varieties.

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

    Directory of Open Access Journals (Sweden)

    Chang-Liang Jing

    2015-08-01

    Full Text Available 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.

  5. State-of-the-art Review : Vol. 2A. Responsive Building Elements

    DEFF Research Database (Denmark)

    Blümel, Ernst; Haghighat, Fariborz; Li, Yuguo;

    This report resumes and presents the activity done in Subtask A of IEA-ECBCS Annex 44 “Integrating Environmentally Responsive Elements in Buildings” concerning the state of the art review of Responsive Building Elements. It is based on the contributions from the participating countries. The publi...

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

    Science.gov (United States)

    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 alga with exposure to Cd(II) seemed to be parameters as biomarkers for metal-induced oxidative stress. PMID:27652004

  7. Effects of dietary vitamin A on antioxidant responses of abalone Haliotis discus hannai Ino

    Institute of Scientific and Technical Information of China (English)

    FU Jinghua; ZHANG Wenbing; MAI Kangsen; FENG Xiuni; XU Wei; LIUFU Zhiguo; TAN Beiping

    2006-01-01

    A 240 d growth experiment was conducted in a re-circulated water system to investigate the effects of dietary vitamin A on growth and antioxidant responses of abalone Haliotis discus hannai Ino. Triplicate groups of juvenile abalone [initial mass was (0.96 ± 0.02) g, shell length was (17.70 ± 0.06) mm] were fed to satiation one of three semi-purified diets containing 0, 1×103, 1×106 IU vitamin A per kilogram diet, respectively. Results showed that the daily increment in shell length (DISL) of abalone in the treatment with 1×103 IU vitamin A per kilogram diet was significantly higher than that with 0 or 1×106 IU vitamin A per kilogram supplementation (P < 0.05). Vitamin A deficiency (0 IU/kg) significantly elevated the activities of superoxide dismutase (SOD), glutathione peroxidase (GPX) and glutathione reductase (GR) in the viscera of abalone (P < 0.05). In muscle, the effects of vitamin A deficiency on SOD and GPX activities were the same as those in viscera, however, the activity of GR significantly decreased (P < 0.05). Vitamin A deficiency significantly decreased the ratio of CAT to SOD (catalase/superoxide dismutase) in viscera (P < 0.05). Nevertheless, it significantly decreased the ratio of GR to GPX in muscle (P < 0.05). Compared with the supplement of 1×103 IU vitamin A per kilogram, excessive vitamin A (1×106 IU/kg) had no significant effects on the activities of CAT, SOD and glutathione-S-transferase (GST) (P > 0.05), but significantly elevated GPX and GR activities in viscera (P < 0.05). In muscle, the activities of CAT, SOD, GPX, GST and GR were significantly decreased by the excessive dietary vitamin A supplement (P < 0.05). Compared with the supplement of 1×103 IU vitamin A per kilogram, vitamin A-excessive had no significant effect on the value of ratio of CAT to SOD either in viscera or in muscle (P>0.05). The ratio of GR to GPX was significantly decreased in viscera, but significantly elevated in muscle in the vitamin A

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

    Institute of Scientific and Technical Information of China (English)

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

    2015-01-01

    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 chaper-ones 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 charac-terizes 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 HSP90a 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.

  9. Serum Oxidative Stress Markers and Lipidomic Profile to Detect NASH Patients Responsive to an Antioxidant Treatment: A Pilot Study

    Directory of Open Access Journals (Sweden)

    Paola Stiuso

    2014-01-01

    Full Text Available Liver steatosis can evolve to steatohepatitis (NASH through a series of biochemical steps related to oxidative stress in hepatocytes. Antioxidants, such as silybin, have been proposed as a treatment of patients with nonalcoholic fatty liver disease (NAFLD and NASH. In this study, we evaluated, in patients with histologically documented NASH, the oxidant/antioxidant status and lipid “fingerprint” in the serum of NASH patients, both in basal conditions and after 12 months of treatment with silybin-based food integrator Realsil (RA. The oxidant/antioxidant status analysis showed the presence of a group of patients with higher basal severity of disease (NAS scores 4.67 ± 2.5 and a second group corresponding to borderline NASH (NAS scores = 3.8 ± 1.5. The chronic treatment with RA changed the NAS score in both groups that reached the statistical significance only in group 2, in which there was also a significant decrease of serum lipid peroxidation. The lipidomic profile showed a lipid composition similar to that of healthy subjects with a restoration of the values of free cholesterol, lysoPC, SM, and PC only in group 2 of patients after treatment with RA. Conclusion. These data suggest that lipidomic and/or oxidative status of serum from patients with NASH could be useful as prognostic markers of response to an antioxidant treatment.

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

    Science.gov (United States)

    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.

  11. Effect of Chitosan Coating on the Postharvest Quality and Antioxidant Enzyme System Response of Strawberry Fruit during Cold Storage

    Directory of Open Access Journals (Sweden)

    Milena Petriccione

    2015-09-01

    Full Text Available The effectiveness of chitosan fruit coating to delay the qualitative and nutraceutical traits of three strawberry cultivars, namely “Candonga”, “Jonica” and “Sabrina”, as well as the effects of chitosan on antioxidant enzymes were evaluated. The fruits were coated with 1% and 2% chitosan solution and stored at 2 °C for nine days. Samples were taken every three days. Physico-chemical (weight loss, soluble solid content and titratable acidity and nutraceutical (total polyphenol, anthocyanin, flavonoid, ascorbic acid content and antioxidant capacity properties along with the enzymatic activity (catalase (CAT, ascorbate peroxidase (APX, polyphenol oxidase (PPO, guaiacol peroxidase (GPX and lipoxygenase (LOX were evaluated. Chitosan treatment significantly reduced water loss and delayed the qualitative changes in color, titratable acidity and ascorbic acid content in dose- and cultivar-dependent manners. Additionally, changes in the total polyphenol, anthocyanin and flavonoid contents and the antioxidant capacity of chitosan-coated strawberry fruits were delayed. Chitosan coating enhanced the activity of some antioxidant enzymes, preventing flesh browning and reducing membrane damage. A global view of the responses of the three strawberry cultivars to chitosan coating and storage temperature was obtained using principal component analysis. Chitosan-coated fruit exhibited a slower rate of deterioration, compared to uncoated fruit in all tested cultivars.

  12. Heat-shock response and antioxidant defense during air exposure in Patagonian shallow-water limpets from different climatic habitats

    OpenAIRE

    Pöhlmann, Kevin; Koenigstein, Stefan; Alter, Katharina; Abele, Doris; Held, Christoph

    2011-01-01

    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...

  13. The protective effect of antioxidants on orbital fibroblasts from patients with Graves’ ophthalmopathy in response to oxidative stress

    OpenAIRE

    Tsai, Chieh-Chih; Wu, Shi-Bei; Kao, Shu-Ching; Kau, Hui-Chuan; Lee, Fenq-Lih; Wei, Yau-Huei

    2013-01-01

    Purpose: To investigate the biphasic effects of hydrogen peroxide (H2O2) on the orbital fibroblasts of patients with Graves’ ophthalmopathy (GO) and the relation to antioxidants and proinflammatory cytokines. Methods Proliferation of cultured orbital fibroblasts from patients with GO and normal controls was evaluated in response to various concentrations of H2O2. The effect of low concentrations of H2O2 (6.25 μM) on the cellular proliferation and induction of intracellular proinflammatory cyt...

  14. Short term supplementation of dietary antioxidants selectively regulates the inflammatory responses during early cutaneous wound healing in diabetic mice

    OpenAIRE

    Park, Na-Young; Lim, Yunsook

    2011-01-01

    Background Diabetic foot ulcers are serious complications for diabetic patients, yet the precise mechanism that underlines the treatment of these diabetic complications remains unclear. We hypothesized that dietary antioxidant supplementation with vitamin C, combined either with vitamin E or with vitamin E and NAC, improves delayed wound healing through modulation of blood glucose levels, oxidative stress, and inflammatory response. Methods Diabetes was induced by administration of alloxan mo...

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

    OpenAIRE

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

    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...

  16. Modeling Reader's Emotional State Response on Document's Typographic Elements

    Directory of Open Access Journals (Sweden)

    Dimitrios Tsonos

    2011-01-01

    Full Text Available We present the results of an experimental study towards modeling the reader's emotional state variations induced by the typographic elements in electronic documents. Based on the dimensional theory of emotions we investigate how typographic elements, like font style (bold, italics, bold-italics and font (type, size, color and background color, affect the reader's emotional states, namely, Pleasure, Arousal, and Dominance (PAD. An experimental procedure was implemented conforming to International Affective Picture System guidelines and incorporating the Self-Assessment Manikin test. Thirty students participated in the experiment. The stimulus was a short paragraph of text for which any content, emotion, and/or domain dependent information was excluded. The Analysis of Variance revealed the dependency of (a all the three emotional dimensions on font size and font/background color combinations and (b the Pleasure dimension on font type and font style. We introduce a set of mapping rules showing how PAD vary on the discrete values of font style and font type elements. Moreover, we introduce a set of equations describing the PAD dimensions' dependency on font size. This novel model can contribute to the automated reader's emotional state extraction in order, for example, to enhance the acoustic rendition of the documents, utilizing text-to-speech synthesis.

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

    Science.gov (United States)

    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.

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

    Science.gov (United States)

    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.

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

    Science.gov (United States)

    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

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

    OpenAIRE

    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 vi...

  1. Ecological responsibility of business as public-private partnership element

    OpenAIRE

    I.M. Potravniy; V.V. Gassiy

    2011-01-01

    In the article the questions of social and ecological responsibility of business are considered within the public-private partnership mechanism framework. Methods of the ecological significant project economic regulation are shown in wildlife management and environment protection sphere.

  2. The effects of Aphis fabae infestation on the antioxidant response and heavy metal content in field grown Philadelphus coronarius plants

    Energy Technology Data Exchange (ETDEWEB)

    Kafel, Alina, E-mail: akafel@us.edu.pl [University of Silesia, Department of Animal Physiology and Ecotoxicology, Bankowa 9, PL 40-007, Katowice (Poland); Nadgorska-Socha, Aleksandra [University of Silesia, Department of Ecology, Bankowa 9, PL 40-007, Katowice (Poland); Gospodarek, Janina [Agricultural University of Krakow, Department of Agricultural Environment Protection, Mickiewicza 21, PL 31-120, Krakow (Poland); Babczynska, Agnieszka; Skowronek, Magda [University of Silesia, Department of Animal Physiology and Ecotoxicology, Bankowa 9, PL 40-007, Katowice (Poland); Kandziora, Marta [University of Silesia, Department of Ecology, Bankowa 9, PL 40-007, Katowice (Poland); Rozpedek, Katarzyna [University of Silesia, Department of Animal Physiology and Ecotoxicology, Bankowa 9, PL 40-007, Katowice (Poland)

    2010-02-01

    The purpose of this study was to explore a possible relationship between the soil availability of metals and their concentrations in various parts of Philadelphuscoronarius plants. Moreover, the possible impact of an aphid infestation on the contamination and antioxidant response of plants from the urban environment of Krakow and the reference rural area of Zagaje Stradowskie (southern Poland) was analyzed. The contents of the glutathione, proline, non-protein - SH groups, antioxidants, and phosphorous and the levels of guaiacol peroxidase and catalase activity in leaves and shoots either infested or not by the aphid Aphis fabae Scop., were measured. The potential bioavailability of metals (Cd; Cu; Ni; Pb; Zn) in the soil and their concentrations in P. coronarius plants originating from both sites were compared. The antioxidant responses were generally elevated in the plants in the polluted area. Such reactions were additionally changed by aphid infestation. Generally, the concentrations of metals in the HNO{sub 3} and CaCl{sub 2} extractants of the soils from two layers at the 0-20 and 20-40 cm depths from the polluted area were higher than in those from the reference area. Such differences were found for nickel and lead (in all examined extractants), zinc (in soil extractants from the layer at 20-40 cm) and cadmium (in HNO{sub 3} extractants). Significant positive relationships between the lead concentrations in the soil and in the plants were found. In the parts of plants from the polluted area, higher concentrations of Pb and Zn (leaves and shoots) and Cd (shoots) were recorded. The shoots and leaves of plants infested with aphids had higher concentrations of Zn but lower Pb. Moreover, their leaves had higher contaminations of Cu and Ni. In conclusion, aphids affected not only the antioxidant response of the plants but also their contamination with metals, especially contamination of the leaves.

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

    Science.gov (United States)

    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.

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

    Directory of Open Access Journals (Sweden)

    Hongtao Yu

    2008-06-01

    Full Text Available 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-Stransferase (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.

  5. Ecological responsibility of business as public-private partnership element

    Directory of Open Access Journals (Sweden)

    I.M. Potravniy

    2011-10-01

    Full Text Available In the article the questions of social and ecological responsibility of business are considered within the public-private partnership mechanism framework. Methods of the ecological significant project economic regulation are shown in wildlife management and environment protection sphere.

  6. Social responsibility as an obligatory element of the institutional system

    OpenAIRE

    Filippova, Irina; Sumcov, Victor

    2012-01-01

    The institute of social responsibility is considered as mandatory addition of market and state institutes, since it reduces the transaction costs of the socio-economic system by eliminating discrimination in the relations. One of the most important missions of the state is the formation and development of the mechanisms of social control.

  7. Moral Responsibility: The Missing Element in Educational Leadership

    Science.gov (United States)

    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…

  8. Oxidative Stress and Antioxidant Responses in Young Leaves of Mulberry Plants Grown Under Nitrogen,Phosphorus or Potassium Deficiency

    Institute of Scientific and Technical Information of China (English)

    Rajesh Kumar Tewari; Praveen Kumar; Parma Nand Sharma

    2007-01-01

    The aim of this study was to associate the generation of reactive oxygen species (ROS) with induced antioxidant responses and disturbed cellular redox environment in the nltrogen-(N), phosphorus-(P), or potassium-(K) deficient mulberry (Morus alba L. var. Kanva-2) plants. The indicators of oxidative stress and cellular redox environment and antioxidant defense-related parameters were analyzed. Deficiency of N, P or K suppressed growth,accelerated senescence, and decreased concentrations of chloroplastic pigments and glutathione. Lipid peroxidation and activities of superoxide dismutase, ascorbate peroxidase and glutathione reductase were also increased in these N, P, or K deprived plants. Concentration of hydrogen peroxide increased in plants deficient in N or P. Deftciency of N or P particularly altered the cellular redox environment as indicated by changes in the redox couples,namely ascorblc acid/total ascorbate decreased in P-, glutathione sulfydryl/total glutathione decreased in N-, and increased in P-deficient plants. Activity staining of native gels for superoxide dismutase revealed increased activity as indicated by increased intensity of bands, and induction of few new isoforms in P- and K-deficient plants.Differences in the patterns of superoxide dismutase isoforms and redox status (ascorbic acid/total ascorbate and glutathlone sulfydryl/total glutathione) indicate that N-, P-, or K-deficiency altered antioxidant responses to varying extents in mulberry plants.

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

    Directory of Open Access Journals (Sweden)

    Nhi-Thi Pham

    2015-07-01

    Full Text Available 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.

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

    Science.gov (United States)

    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

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

    Science.gov (United States)

    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.

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

    Science.gov (United States)

    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.

  13. Effects of the amplitude and frequency of salinity fluctuations on antioxidant responses in juvenile tongue sole, Cynoglossus semilaevis

    Directory of Open Access Journals (Sweden)

    Sachin O. Khairnar

    2016-06-01

    Full Text Available To understand the tolerance of tongue sole, Cynoglossus semilaevis, to varying salinities, the effects of the amplitude (2, 4, 6 and 8 g/L and frequency (2, 4 and 8 days of salinity fluctuations on the activities of antioxidant responses, including acidic phosphatase (ACP, alkaline phosphatase (AKP, catalase (CAT and superoxide dismutase (SOD from antioxidant system in liver, muscle, gills and kidney, were investigated in this study. The results showed that the antioxidant responses of tongue sole were highly tissue-specific during the varying salinity fluctuations. In all tissues, ACP and AKP activity was found to be highest at moderate salinity fluctuations compared to the control, low and high salinity treatments (p<0.05. SOD and CAT activities had significant effect due to salinity fluctuations in all tissues (p<0.05, except in hepatic and renal tissues. Variations in branchial SOD activity proved that salinity fluctuations had greater impact on tongue sole at moderate and high fluctuating salinities compared to the control and low fluctuating salinities, whereas the branchial CAT activities showed contrasting trend. Further, cortisol levels were significantly affected in lower and higher salinity fluctuations. However, plasma cortisol levels remained low in moderate salinity fluctuations and control (p<0.05. Taken together, the results indicated that salinity fluctuations could effectively stimulate and enhance the antioxidant enzyme activity in the liver, kidney, gills and muscle of the juvenile tongue sole, thus effectively eliminating the excessive reactive oxygen species and minimizing the body damage in tongue sole or could be for any other euryhaline teleosts.

  14. Differential Responses of the Activities of Antioxidant Enzymes to Thermal Stresses between Two Invasive Eupatorium Species in China

    Institute of Scientific and Technical Information of China (English)

    Ping Lu; Wei-Guo Sang; Ke-Ping Ma

    2008-01-01

    The effect of thermal stress on the antioxidant system was Investigated in two invasive plants, Eupatorlum adenophorum Spreng. and E. odoratum L. The former is sensitive to high temperature, whereas the latter is sensitive to low temperature.Our aim was to explore the relationship between the response of antioxidant enzymes and temperature In the two Invasive weeds with different distribution patterns in China. Plants were transferred from glasshouse to growth chambers at a constant 25 ℃ for 1 week to acclimatize to the environment. For the heat treatments, temperature was Increased stepwise to 30, 35, 38 and finally to 42 ℃. For the cold treatments, temperature was decreased stepwise to 20, 15,10 and finally to 5 ℃.Plants were kept In the growth chambers for 24 h at each temperature step. In E. adenophorum, the coordinated Increase of the activities of antioxidant enzymes was effective In protecting the plant from the eccumulatlon of active oxygen species (AOS) at low temperature, but the activities of catalase (CAT), guaiacol peroxidase (POD), ascorbate peroxidase (APX),glutathione reductase (GR), and monodehydroascorbate reductase (MDAR) were not accompanied by the Increase of super-oxide dismutase (SOD) during the heat treatments. As a result, the level of lipid peroxidation in E. adenophorum was higher under heat stress than under cold stress. In E. odoratum, however, the lesser degree of membrane damage, as indicated by low monodehydroascorbate content, and the coordinated Increase of the oxygen. Dstoxlfying enzymes were observed in hest-treated plants, but the antioxidant enzymes were unable to operate in cold stress. This indicates that the plants have a higher capacity for scavenging oxygen radicals in heat stress than in cold stress. The different responses of antloxidant enzymes may be one of the possible mechanisms of the differences in temperature sensitivities of the two plant species.

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

    Science.gov (United States)

    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.

  16. Control of antioxidative response by the tumor suppressor protein PML through regulating Nrf2 activity

    Science.gov (United States)

    Guo, Shuang; Cheng, Xiwen; Lim, Jun-Hee; Liu, Yu; Kao, Hung-Ying

    2014-01-01

    Oxidative stress is a consequence of an imbalance between reactive oxygen species (ROS) production and the ability of the cytoprotective system to detoxify the reactive intermediates. The tumor suppressor promyelocytic leukemia protein (PML) functions as a stress sensor. Loss of PML results in impaired mitochondrial complex II activity, increased ROS, and subsequent activation of nuclear factor erythroid 2–related factor 2 (Nrf2) antioxidative pathway. We also demonstrate that sulforaphane (SFN), an antioxidant, regulates Nrf2 activity by controlling abundance and subcellular distribution of PML and that PML is essential for SFN-mediated ROS increase, Nrf2 activation, antiproliferation, antimigration, and antiangiogenesis. Taking the results together, we have uncovered a novel antioxidative mechanism by which PML regulates cellular oxidant homeostasis by controlling complex II integrity and Nrf2 activity and identified PML as an indispensable mediator of SFN activity. PMID:24943846

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

    Science.gov (United States)

    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 levels in MeHg-exposed adolescent offspring were significantly lower than their controls (p levels of iron, zinc, copper and manganese were increased compared to sham-lesioned offspring (p levels thereby promoting toxicity (p 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 antioxidant capacity. This may reflect a mechanism by which methylmercury exerts its neurotoxicity and/or predispose offspring to further neurological insults during adulthood.

  18. The NRF2 Activation and Antioxidative Response Are Not Impaired Overall during Hyperoxia-Induced Lung Epithelial Cell Death

    Directory of Open Access Journals (Sweden)

    Haranatha R. Potteti

    2013-01-01

    Full Text Available Lung epithelial and endothelial cell death caused by pro-oxidant insults is a cardinal feature of acute lung injury/acute respiratory distress syndrome (ALI/ARDS patients. The NF-E2-related factor 2 (NRF2 activation in response to oxidant exposure is crucial to the induction of several antioxidative and cytoprotective enzymes that mitigate cellular stress. Since prolonged exposure to hyperoxia causes cell death, we hypothesized that chronic hyperoxia impairs NRF2 activation, resulting in cell death. To test this hypothesis, we exposed nonmalignant small airway epithelial cells (AECs to acute (1–12 h and chronic (36–48 h hyperoxia and evaluated cell death, NRF2 nuclear accumulation and target gene expression, and NRF2 recruitment to the endogenous HMOX1 and NQO1 promoters. As expected, hyperoxia gradually induced death in AECs, noticeably and significantly by 36 h; ~60% of cells were dead by 48 h. However, we unexpectedly found increased expression levels of NRF2-regulated antioxidative genes and nuclear NRF2 in AECs exposed to chronic hyperoxia as compared to acute hyperoxia. Chromatin Immunoprecipitation (ChIP assays revealed an increased recruitment of NRF2 to the endogenous HMOX1 and NQO1 promoters in AECs exposed to acute or chronic hyperoxia. Thus, our findings demonstrate that NRF2 activation and antioxidant gene expression are functional during hyperoxia-induced lung epithelial cell death and that chronic hyperoxia does not impair NRF2 signaling overall.

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

    Science.gov (United States)

    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

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

    Science.gov (United States)

    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.

  1. Different responses of tobacco antioxidant enzymes to light and chilling stress

    NARCIS (Netherlands)

    Gechev, T; Willekens, H; Van Montagu, M; Inze, D; Van Camp, W; Toneva, [No Value; Minkov, [No Value

    2003-01-01

    The effect of elevated light treatment (25 degreesC, PPFD 360 mumol m(-2) sec(-1)) or chilling temperatures combined with elevated light (5 degreesC, PPFD 360 mumol m-2 sec-1) on the activity of six antioxidant enzymes, guaiacol peroxidases, and glutathione peroxidase (GPx, EC 1.11.1.9) protein accu

  2. Kinetics of the Anti-oxidant Response to Salinity in the Halophyte Cakile maritima

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    The effects of NaCl stress on the activity of anti-oxidant enzymes (superoxide dismutase, catalase (CAT), peroxidase (POD),ascorbate peroxidase (APX), monodehydroascorbate reductase, dehydroascorbate reductase (DHAR), and glutathione reductase (GR)), anti-oxidant molecules (ascorbate and glutathione), and parameters of oxidative stress (malondialdehyde (MDA), electrolyte leakage, and H2O2 concentrations) were investigated in Cakile maritima, a halophyte frequent along the Tunisian seashore. Seedlings were grown in the presence of salt (100, 200, and 400 mmol/L NaCl). Plants were harvested periodically over 20 days. Growth was maximal in the presence of 0-100 mmol/L NaCl. At 400 mmol/L NaCl, growth decreased significantly. The salt tolerance of C. maritima, at moderate salinities, was associated with the lowest values of the parameters indicative of oxidative stress, namely the highest activities of POD, CAT, APX, DHAR, and GR and high tissue content of ascorbate and glutathione. However, prolonged exposure to high salinity resulted in a decrease in anti-oxidant activities and high MDA content, electrolyte leakage, and H2O2 concentrations. These results suggest that anti-oxidant systems participate in the tolerance of C. maritima to moderate salinities.

  3. Reactive oxygen species (ROS and response of antioxidants as ROS-scavengers during environmental stress in plants

    Directory of Open Access Journals (Sweden)

    Kaushik eDas

    2014-12-01

    Full Text Available Reactive oxygen species (ROS were initially recognized as toxic by-products of aerobic metabolism. In recent years, it has become apparent that ROS plays an important signaling role in plants, controlling processes such as growth, development and especially response to biotic and abiotic environmental stimuli. The major members of the ROS family include free radicals like O2● −, OH● and non-radicals like H2O2 and 1O2. The ROS production in plants is mainly localized in the chloroplast, mitochondria and peroxisomes. There are secondary sites as well like the endoplasmic reticulum, cell membrane, cell wall and the apoplast. The role of the ROS family is that of a double edged sword; while they act as secondary messengers in various key physiological phenomena, they also induce oxidative damages under several environmental stress conditions like salinity, drought, cold, heavy metals, UV irradiation etc., when the delicate balance between ROS production and elimination, necessary for normal cellular homeostasis, is disturbed. The cellular damages are manifested in the form of degradation of biomolecules like pigments, proteins, lipids, carbohydrates and DNA, which ultimately amalgamate in plant cellular death. To ensure survival, plants have developed efficient antioxidant machinery having two arms, (i enzymatic components like superoxide dismutase (SOD, catalase (CAT, ascorbate peroxidase (APX, guaiacol peroxidase (GPX, glutathione reductase (GR, monodehydroascorbate reductase (MDHAR and dehydroascorbate reductase (DHAR; (ii non-enzymatic antioxidants like ascorbic acid (AA, reduced glutathione (GSH, α-tocopherol, carotenoids, flavonoids and the osmolyte proline. These two components work hand in hand to scavenge ROS. In this review, we emphasize on the different types of ROS, their cellular production sites, their targets, and their scavenging mechanism mediated by both the branches of the antioxidant systems, highlighting the potential

  4. Plasma antioxidant responses and oxidative stress following a 20 meter shuttle run test in female volleyball players

    Directory of Open Access Journals (Sweden)

    Emre Özgür Bulduk

    2011-08-01

    Full Text Available The effect of physical exercise on oxidant stress and antioxidants has been investigated extensively in the last twenty years. Cells continuously produce free radicals under normal conditions during mitochondrial electron transport chain (ETC. Experimental studies have shown elevated metabolic rate by strenuous physical exercise induces oxidative stress and production of excessive amounts of free radicals. Lipid peroxidation occurs when free radicals react with cellular components involving polyunsaturated fatty acid residues of phospholipids which are very sensitive to oxidation. This study aimed to determine plasma antioxidant responses and oxidative stress following a 20 meter shuttle run test in female volleyball players. Ten female volleyball players from the same team, and ten sedentary female ages between 18-24 years old volunteered to participate in this study. They were in good health and 48 hours before the test did not receive any drug or alcohol. None of them had any endocrine, orthopedic problems. Before the study, Informed, written consent was obtained from all the participants after full explanation of the procedures involved. All procedures were approved by the Selçuk University Meram Medical School of Ethical Committee. 20 meter shuttle run test was designed to estimate the maximal aerobic power of athletes performing in sports with frequent stops and starts (eg. Basketball, volleyball, fencing and so on. Findings of our study demonstrate that in both female groups 20 meter shuttle run test leads to production of more reactive oxygen species than the antioxidant systems can scavenge. Decrease in the activities of these antioxidant enzymes may be due to their inactivation caused by the higher production of the free radicals. it seems that the vulnerability of the body to oxidative stress is significantly enhanced after strenuous exercise test.

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

    Science.gov (United States)

    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. PMID:26980113

  6. Antioxidant and oxidative stress responses of sojourners at high altitude in different climatic temperatures

    Science.gov (United States)

    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.

  7. Response Pattern of Antioxidants to Lipid Peroxide Concentration in Carbon Tetrachloride-Induced Hepato-Toxicity Is Tightly Logistic in Rabbits

    OpenAIRE

    Alisi C. S.; Ojiako O. A.; Osuagwu C. G.; Onyeze G. O. C.

    2011-01-01

    Logistic response of antioxidants to lipid peroxide concentration in carbon tetrachloride toxicity in rabbit liver was evaluated. Carbon tetrachloride (CCl4), ethanol extracts of Chromolaena odorata (ETECO), sylimarin (a known hepatoprotective agent) and water, were used to induce variations in the oxidant/antioxidant balance in the test and control animals. This was used as a model to study the delicate balance between the activities and/or the intracellular concentrations of ...

  8. Oxidative Stress and Erythrocyte Membrane Responses During Sarcoptic Mange in Sheep: Evaluating Bio-Organic Therapy and its Supplementation with Antioxidant Tocopherol.

    OpenAIRE

    Umesh Dimri; M C Sharma; Meena Kataria; Sushil Kumar

    2005-01-01

    Sarcoptic mange in sheep, causes heavy losses in quantity and quality of wool and meat production.The present investigation aimed at evaluating the oxidative stress-antioxidant defense and erythrocytic membrane responses during sarcoptic mange in sheep.A bio-organic therapy (BT) was evaluated for its efficacy. Tocopherol was assessed for its antioxidant adjunctive potential. Materials and Methods: Nineteen sheep with sarcoptic mange (aged 9-12 months, with lesions ascribed to Sarcoptes scabie...

  9. Optimization of Extraction Condition of Bee Pollen Using Response Surface Methodology: Correlation between Anti-Melanogenesis, Antioxidant Activity, and Phenolic Content

    OpenAIRE

    Seon Beom Kim; Yang Hee Jo; Qing Liu; Jong Hoon Ahn; In Pyo Hong; Sang Mi Han; Bang Yeon Hwang; Mi Kyeong Lee

    2015-01-01

    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...

  10. The toxic effects of ammonia exposure on antioxidant and immune responses in Rockfish, Sebastes schlegelii during thermal stress.

    Science.gov (United States)

    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.

  11. Optimization extraction conditions for improving phenolic content and antioxidant activity in Berberis asiatica fruits using response surface methodology (RSM).

    Science.gov (United States)

    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. PMID:27080887

  12. Vibration response mechanism of faulty outer race rolling element bearings for quantitative analysis

    Science.gov (United States)

    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.

  13. Control of antioxidative response by the tumor suppressor protein PML through regulating Nrf2 activity

    OpenAIRE

    GUO Shuang; Cheng, Xiwen; Lim, Jun-Hee; Yu LIU; Kao, Hung-Ying

    2014-01-01

    Oxidative stress is a consequence of an imbalance between reactive oxygen species (ROS) production and the ability of the cytoprotective system to detoxify the reactive intermediates. The tumor suppressor promyelocytic leukemia protein (PML) functions as a stress sensor. Loss of PML results in impaired mitochondrial complex II activity, increased ROS, and subsequent activation of nuclear factor erythroid 2–related factor 2 (Nrf2) antioxidative pathway. We also demonstrate that sulforaphane (S...

  14. Implications of chronic daily anti-oxidant administration on the inflammatory response to intracortical microelectrodes

    Science.gov (United States)

    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.

  15. Copper-induced response of physiological parameters and antioxidant enzymes in the aquatic macrophyte Potamogeton pusillus

    Energy Technology Data Exchange (ETDEWEB)

    Monferran, Magdalena V.; Sanchez Agudo, Jose A. [Universidad Nacional de Cordoba - CONICET, Facultad de Ciencias Quimicas, Dto. Bioquimica Clinica - CIBICI, Medina Allende Esq., Haya de la Torre, Ciudad Universitaria, 5000 Cordoba (Argentina); Pignata, Maria L. [Universidad Nacional de Cordoba - CONICET, Facultad de Ciencias Exactas, Fisicas y Naturales - IMBIV, Ciudad Universitaria, 5000 Cordoba (Argentina); Wunderlin, Daniel A., E-mail: dwunder@fcq.unc.edu.a [Universidad Nacional de Cordoba - CONICET, Facultad de Ciencias Quimicas, Dto. Bioquimica Clinica - CIBICI, Medina Allende Esq., Haya de la Torre, Ciudad Universitaria, 5000 Cordoba (Argentina)

    2009-08-15

    Bioaccumulation and toxicity of copper was evaluated on Potamogeton pusillus L. The effect of copper (5-100 mug L{sup -1}) applied for several days was assessed by measuring changes in the chlorophyll's, phaeophytin's, malondialdehyde, electrical conductivity, glutathione peroxidase (GPX), glutathione reductase (GR) and guaiacol peroxidase (POD) activities. Plants accumulated copper with a maximum of 162 mug g{sup -1} dw after 7-days exposure at 100 mug L{sup -1}, however most of the metal was accumulated after 1-day exposure. The toxic effect caused by Cu was evident by the reduction of photosynthetic pigments, increase of malondialdehyde and electrical conductivity. P. pusillus shows Cu-induced oxidative stress by modulating antioxidant enzymes like GPX, GR and POD. Antioxidant enzymes activity increased significantly after exposure to 40 mug L{sup -1} during 24 h, followed by a drop at longer times. Thus, P. pusillus is proposed as a good biomonitor for the assessment of metal pollution in aquatic ecosystems. - The tolerance of Potamogeton pusillus to copper largely depends on the enhanced activity of its antioxidant system, showing that a decrease on its activity favored oxidative stress and cell damage.

  16. Responses of antioxidant defense system of Lespedeza davurica to enhanced UV-B radiation

    International Nuclear Information System (INIS)

    The objective of this study was to investigate the effects of different UV-B radiation intensity (CK, T1, T2) on antioxidant defense system and other related indicators of Lespedeza davurica (Laxm.) Schindl. Malonaldehyde (MDA), ascorbic acid (AsA) and carotenoid (Car) contents, as well as superoxide dismutase (SOD), peroxidase (POD), catalase (CAT) and ascorbate peroxidase (APX) activities of leaves from Lespedeza davurica under different UV-B radiation intensity were investigated. Samples were collected once every three days. The UV-B treatment was continued 15 days. Result indicated that SOD and POD activities decreased, APX and POD activities increased with UV-B radiation enhanced during the whole treatment time. SOD, POD and CAT activities decreased with UV-B radiation intensity increasing. APX activity increased during the first 9-day treatment with radiation intensity increasing then decreased with radiation intensity increasing. UV-B radiation increased AsA content, decreased Car content. Both AsA and Car contents decreased with radiation intensity increasing when compared with control. O2- and MDA increased with radiation intensity increasing. All other tested indicators increased except SOD and POD activity as well as AsA content decreased after UV-B radiation treatment. Comprehensive evaluation of subordinate function showed that UV-B radiation reduced the antioxidant capacity of Lespedeza davurica, and the antioxidant capacity decreased with UV-B radiation intensity increasing. (author)

  17. Response of antioxidant defences to Zn stress in three duckweed species.

    Science.gov (United States)

    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

  18. Divergences in hormonal and enzymatic antioxidant responses of two Chicory ecotypes to salt stress.

    Science.gov (United States)

    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

  19. Response and adaptation of photosynthesis, respiration, and antioxidant systems to elevated CO2 with environmental stress in plants

    Directory of Open Access Journals (Sweden)

    Zhenzhu eXu

    2015-09-01

    Full Text Available 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.

  20. Light history modulates antioxidant and photosynthetic responses of biofilms to both natural (light) and chemical (herbicides) stressors.

    Science.gov (United States)

    Bonnineau, Chloé; Sague, Irene Gallardo; Urrea, Gemma; Guasch, Helena

    2012-05-01

    In multiple stress situations, the co-occurrence of environmental and chemical factors can influence organisms' ability to cope with toxicity. In this context, the influence of light adaptation on the response of freshwater biofilms to sudden light changes or to herbicides exposure was investigated by determining various parameters: diatom community composition, photosynthetic parameters, chlorophyll a content, antioxidant enzyme activities. Biofilms were grown in microcosms under sub-optimal, saturating, and high light intensities and showed already described characteristics of shade/light adaptation (community structure, photosynthetic adaptation, etc.). Light history modulated antioxidant and photosynthetic responses of biofilms to the stress caused by short-term exposure to sudden light changes or to herbicides. First biofilms adapted to sub-optimal light intensity (shade-adapted) were found to be more sensitive to an increase in light intensity than high-light adapted ones to a reduction in light intensity. Second, while light history influenced biofilms' response to glyphosate, it had little influence on biofilms' response to copper and none on its response to oxyfluorfen. Indeed glyphosate exposure led to a stronger decrease in photosynthetic efficiency of shade-adapted biofilms (EC(50) = 11.7 mg L(-1)) than of high-light adapted communities (EC(50) = 35.6 mg L(-1)). Copper exposure led to an activation of ascorbate peroxidase (APX) in biofilms adapted to sub-optimal and saturating light intensity while the protein content decreased in all biofilms exposed to copper. Oxyfluorfen toxicity was independent of light history provoking an increase in APX activity. In conclusion this study showed that both previous exposure to contaminants and physical habitat characteristics might influence community tolerance to disturbances strongly. PMID:22407402

  1. Hepatic and Nephric NRF2 Pathway Up-Regulation, an Early Antioxidant Response, in Acute Arsenic-Exposed Mice

    Directory of Open Access Journals (Sweden)

    Jinlong Li

    2015-10-01

    Full Text Available 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.

  2. Effects of segregation of primary alloying elements on the creep response in magnesium alloys

    DEFF Research Database (Denmark)

    Huang, Y.D.; Dieringa, H.; Hort, N.;

    2008-01-01

    The segregation of primary alloying elements deteriorates the high temperature creep resistance of magnesium alloys. Annealing at high temperatures alleviating their segregations can improve the creep resistance. Present investigation on the effect of segregation of primary alloying elements...... on the creep response may provide some useful information about how to improve the creep resistance of magnesium alloys in the future. (c) 2008 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved....

  3. A role for neuronal cAMP responsive-element binding (CREB)-1 in brain responses to calorie restriction

    OpenAIRE

    Fusco, Salvatore; Ripoli, Cristian; Podda, Maria Vittoria; Ranieri, Sofia Chiatamone; Leone, Lucia; Toietta, Gabriele; McBurney, Michael W.; Schütz, Günther; Riccio, Antonella; Grassi, Claudio; Galeotti, Tommaso; Pani, Giovambattista

    2011-01-01

    Calorie restriction delays brain senescence and prevents neurodegeneration, but critical regulators of these beneficial responses other than the NAD+-dependent histone deacetylase Sirtuin-1 (Sirt-1) are unknown. We report that effects of calorie restriction on neuronal plasticity, memory and social behavior are abolished in mice lacking cAMP responsive-element binding (CREB)-1 in the forebrain. Moreover, CREB deficiency drastically reduces the expression of Sirt-1 and the induction of genes r...

  4. Role of oxidative stress in disrupting the function of negative glucocorticoid response element in daily amphetamine-treated rats.

    Science.gov (United States)

    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

  5. Induction of electrophile-responsive element (EpRE)-mediated gene expression by tomato extracts in vitro.

    Science.gov (United States)

    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.

  6. Response of removable epoxy foam exposed to fire using an element death model.

    Energy Technology Data Exchange (ETDEWEB)

    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.

  7. Finite element analysis of dynamic response and structure borne noise of gearbox

    Institute of Scientific and Technical Information of China (English)

    LIU Wen; LIN Teng-jiao; LI Run-fang; DU Xue-song

    2007-01-01

    A dynamic finite element method combined with finite element mixed formula for contact problem is used to analyze the dynamic characteristics of gear system. Considering the stiffness excitation, error excitation and meshing shock excitation, the dynamic finite element model is established for the entire gear system which includes gears, shafts, bearings and gearbox housing. By the software of I-DEAS, the natural frequency, normal mode, dynamic time-domain response, frequency-domain response and one-third octave velocity grade structure borne noise of gear system are studied by the method of theoretical modal analysis and dynamic response analysis. The maximum values of vibration and structure borne noise are occurred at the mesh frequency of output grade gearing.

  8. Antioxidant response of Stevia rebaudiana B. to polyethylene glycol and paclobutrazol treatments under in vitro culture.

    Science.gov (United States)

    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. PMID:24604127

  9. The use of antioxidant enzymes in freshwater biofilms: temporal variability vs. toxicological responses.

    Science.gov (United States)

    Bonnineau, Chloé; Tlili, Ahmed; Faggiano, Leslie; Montuelle, Bernard; Guasch, Helena

    2013-07-15

    This study aims to investigate the potential of antioxidant enzyme activities (AEA) as biomarkers of oxidative stress in freshwater biofilms. Therefore, biofilms were grown in channels for 38 days and then exposed to different concentrations (0-150 μg L(-1)) of the herbicide oxyfluorfen for 5 more weeks. Under control conditions, the AEA of biofilms were found to change throughout time with a significant increase in ascorbate peroxidase (APX) activity during the exponential growth and a more important role of catalase (CAT) and glutathione reductase (GR) activities during the slow growth phase. Chronic exposure to oxyfluorfen led to slight variations in AEA, however, the ranges of variability of AEA in controls and exposed communities were similar, highlighting the difficulty of a direct interpretation of AEA values. After 5 weeks of exposure to oxyfluorfen, no clear effects were observed on chl-a concentration or on the composition of other pigments suggesting that algal group composition was not affected. Eukaryotic communities were structured clearly by toxicant concentration and both eukaryotic and bacterial richness were reduced in communities exposed to the highest concentration. In addition, during acute exposure tests performed at the end of the chronic exposure, biofilms chronically exposed to 75 and 150 μg L(-1) oxyfluorfen showed a higher CAT activity than controls. Chronic exposure to oxyfluorfen provoked then structural changes but also functional changes in the capacity of biofilm CAT activity to respond to a sudden increase in concentration, suggesting a selection of species with higher antioxidant capacity. This study highlighted the difficulty of interpretation of AEA values due to their temporal variation and to the absence of absolute threshold value indicative of oxidative stress induced by contaminants. Nevertheless, the determination of AEA pattern throughout acute exposure test is of high interest to compare oxidative stress levels

  10. Antioxidant response of Stevia rebaudiana B. to polyethylene glycol and paclobutrazol treatments under in vitro culture.

    Science.gov (United States)

    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.

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

    DEFF Research Database (Denmark)

    Hansen, Henning Gram; Schmidt, Jonas Damgard; Soltoft, Cecilie Lutzen;

    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...... 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...

  12. Antioxidant enzyme activities of Microcystis aeruginosa in response to nonylphenols and degradation of nonylphenols by M. aeruginosa.

    Science.gov (United States)

    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

  13. Biochemical composition and antioxidant activities of Arthrospira (Spirulina) platensis in response to gamma irradiation.

    Science.gov (United States)

    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

  14. Effect of chromium on accumulation and antioxidants in Cucumis utillissimus L.: Response under enhanced bioavailability condition

    Institute of Scientific and Technical Information of China (English)

    Geetgovind Sinam; Sarita Sinha; Shekhar Mallick

    2011-01-01

    This study compares the accumulation of Ct(VI) and biochemical changes (total chlorophyll, carotenoid, protein, malondialdehyde (MDA) and cysteine contents) and roles of antioxidant enzymes (superoxide dismutase (SOD), guaiacol peroxidase (GPX), ascorbate peroxidase (APX)) in tolerance to metal induced stress in Cucumis utillissimus L. grown in Cr contaminated soil (CS) with garden soil (GS). Furthermore, Cr bioavailability was enhanced by ethylene diamine tetra-acetic acid (EDTA) addition to the soil to forecast the plant's accumulation pattern at elevated Cr environment. Accumulation of Cr in the leaves of the plant increased with increase in substrate metals concentration. It further increased with the addition of EDTA by 1437% and 487% in GS and CS, respectively at the highest treatment level. The lipid peroxidation increased proportionately with increase in Cr accumulation in the leaves. All the activity of antioxidant enzymes (SOD, GPX and APX) and the level of cysteine increased with dose dependant manner. SOD and cysteine were observed to be higher in the GS than in CS, but APX and GPX were found to be higher in CS than in GS. The increase in GPX and APX activities with the increase in Cr concentration could be assumed that these two enzymes have a major role in the defense mechanism towards stress induced by Cr in C. utillissimus.

  15. Antioxidative responses during germination in quinoa grown in vitamin B-rich medium.

    Science.gov (United States)

    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

  16. Toxic effects of chlortetracycline on maize growth, reactive oxygen species generation and the antioxidant response

    Institute of Scientific and Technical Information of China (English)

    Bei Wen; Yu Liu; Peng Wang; Tong Wu; Shuzhen Zhang; Xiaoquan Shan; Jingfen Lu

    2012-01-01

    The toxicity of chlortetracycline (CTC) on maize (Zea mays L.) growth and reactive oxygen species (ROS) generation was studied.The root and shoot lengths and fresh weights of maize seedlings were inhibited by CTC treatment (p < 0.05).Root length was more sensitive than other parameters with the EC10 value of 0.064 mg/L.The spin trapping technique followed by electron paramagnetic resonance (EPR) analysis was used to quantify the ROS production.The ROS generated in maize roots after exposure to CTC was identified as hydroxyl radical (-OH).The EPR signal intensity correlated positively with the logarithm of CTC concentrations exposed (p < 0.05).The dynamic changes of malondialdehyde (MDA) contents and the antioxidative enzyme activities in maize roots were also determined.As compared to the control group,CTC was found to significantly increase MDA content.Treatment of maize roots with the ·OH scavenger sodium benzoate (SB) reduced the MDA content and enhanced the antioxidative enzyme activities.The results demonstrated the harmfulness of CTC at high dose to maize in the early developmental stage,and clarified that the inducement of ·OH is one of the mechanisms of CTC toxicity.

  17. [Effects of exogenous EBR and NO signal on antioxidant system and low response gene expression under cold stress on maize embryo].

    Science.gov (United States)

    Ma, Jin-hu; Xing, Guo-fang; Yang, Xiao-huan; Wang, Yu-guo; Du, Hui-ling

    2015-05-01

    In this study, Xianyu 335, a maize hybrid, was used to investigate the effects of 24-Epibrassinolide (EBR, a synthetic BR) on antioxidant capacity and low-temperature response gene expression in maize embryo germination under low temperature (LT) stress. The germination rate of maize seeds under LT stress was not affected by EBR, but the seed activity index and seedling growth were improved. EBR increased the activities of some antioxidative enzymes including SOD, POD, CAT and GR, and the contents of non-enzymatic antioxidants, such as GSH and proline, and induced the accumulation of nitric oxide (NO). NO scavenging c-PTIO and NOS inhibitor L- NAME decreased but NO donor SNP increased the enzyme activities of CAT and POD, and the content of proline, indicating NO mediated the EBR-induced antioxidant capacity. The gene expression pattern analysis showed that the expression of P5CS1, CBF1, CBF3 and COR15a was induced by LT stress, and further increased by EBR treatment in maize embryo, while their expression was suppressed by c-PTIO and L-NAME, and improved by SNP, which implied LT-responsed genes were regulated by NO. These results demonstrated that NO was involved in the EBR-induced LT tolerance in maize embryo by modulating the antioxidative capacity and the expression of LT-responsive genes. PMID:26571659

  18. Chronic hyperbaric oxygen treatment elicits an anti-oxidant response and attenuates atherosclerosis in apoE knockout mice.

    Science.gov (United States)

    Kudchodkar, Bhalchandra J; Pierce, Anson; Dory, Ladislav

    2007-07-01

    We previously demonstrated that hyperbaric oxygen (HBO) treatment inhibits diet-induced atherosclerosis in New Zealand White rabbits. In the present study we investigate the mechanisms that might be involved in the athero-protective effect of HBO treatment in a well-accepted model of atherosclerosis, the apoE knockout (KO) mouse. We examine the effects of daily HBO treatment (for 5 and 10 weeks) on the components of the anti-oxidant defense mechanism and the redox state in blood, liver and aortic tissues and compare them to those of untreated apoE KO mice. HBO treatment results in a significant reduction of aortic cholesterol content and decreased fatty streak formation. These changes are accompanied by a significant reduction of autoantibodies against oxidatively modified LDL and profound changes in the redox state of the liver and aortic tissues. A 10-week treatment significantly reduces hepatic levels of TBARS and oxidized glutathione, while significantly increases the levels of reduced glutathione, glutathione reductase (GR), transferase, Se-dependent glutathione peroxidase and catalase (CAT). The effects of HBO treatment are similar in the aortic tissues. These observations provide evidence that HBO treatment has a powerful effect on the redox state of relevant tissues and produces an environment that inhibits oxidation. The anti-oxidant response may be the key to the anti-atherogenic effect of HBO treatment. PMID:16973170

  19. Optimization of infrared-assisted extraction of Bletilla striata polysaccharides based on response surface methodology and their antioxidant activities.

    Science.gov (United States)

    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

  20. Response of antioxidant enzymes, ascorbate and glutathione metabolism towards cadmium in hyperaccumulator and nonhyperaccumulator ecotypes of Sedum alfredii H.

    Science.gov (United States)

    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

  1. Characterization of a retinoic acid responsive element isolated by whole genome PCR.

    OpenAIRE

    Costa-Giomi, M P; Gaub, M P; Chambon, P; Abarzúa, P

    1992-01-01

    We have used whole PCR in an attempt to isolate novel retinoic acid (RA) responsive genes. We cloned several small genomic fragments from total human DNA containing putative retinoic acid responsive elements (RAREs) selected by direct binding to the retinoic acid receptor alpha (RAR alpha). We report here that an oligonucleotide containing a sequence from one of the cloned human DNA fragments, and referred to as alpha 1, functions as an authentic RARE. It is shown that both RAR alpha and RAR ...

  2. Application of ADINA fluid element for transient response analysis of fluid-structure system

    International Nuclear Information System (INIS)

    Pressure propagation and Fluid-Structure Interaction (FSI) in 3D space were simulated by general purpose finite element program ADINA using the displacement-based fluid element which presumes inviscid and compressible fluid with no net flow. Numerical transient solution was compared with the measured data of an FSI experiment and was found to fairly agree with the measured. In the next step, post analysis was conducted for a blowdown experiment performed with a 1/7 scaled reactor pressure vessel and a flexible core barrel and the code performance was found to be satisfactory. It is concluded that the transient response of the core internal structure of a PWR during the initial stage of LOCA can be analyzed by the displacement-based finite fluid element and the structural element. (orig.)

  3. Simulation of Electromagnetic Wave Logging Response in Deviated Wells Based on Vector Finite Element Method

    Institute of Scientific and Technical Information of China (English)

    LV Wei-Guo; CHU Zhao-Tan; ZHAO Xiao-Qing; FAN Yu-Xiu; SONG Ruo-Long; HAN Wei

    2009-01-01

    The vector finite element method of tetrahedral elements is used to model 3D electromagnetic wave logging response. The tangential component of the vector field at the mesh edges is used as a degree of freedom to overcome the shortcomings of node-based finite element methods. The algorithm can simulate inhomogeneous media with arbitrary distribution of conductivity and magnetic permeability. The electromagnetic response of well logging tools are studied in dipping bed layers with the borehole and invasion included. In order to simulate realistic logging tools, we take the transmitter antennas consisting of circular wire loops instead of magnetic dipoles. We also investigate the apparent resistivity of inhomogeneous formation for different dip angles.

  4. Pounding Effects on the Earthquake Response of Adjacent Reinforced Concrete Structures Strengthened by Cable Elements

    Directory of Open Access Journals (Sweden)

    Liolios Angelos

    2014-06-01

    Full Text Available 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.

  5. Responses of trace elements to aerobic maximal exercise in elite sportsmen.

    Science.gov (United States)

    Otag, Aynur; Hazar, Muhsin; Otag, Ilhan; Gürkan, Alper Cenk; Okan, Ilyas

    2014-05-01

    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 sportsman performance but also in terms of future healthy life plans and clinically. PMID:24762350

  6. Development of Finite Element Response Model for Mechanistic - Empirical Design of Flexible Pavement

    Directory of Open Access Journals (Sweden)

    Mujtaba A. AHMED

    2012-08-01

    Full Text Available The focus of this work is to present a finite element method (FEM-based program of the M-E design on MATLAB protocol. The response output generated at critical locations are presented. The results were then compared with those from a locally available program called ‘NEMPADS’ and a reasonable comparison were achieved.

  7. Uterine deletion of Trp53 compromises antioxidant responses in mouse decidua

    Energy Technology Data Exchange (ETDEWEB)

    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.

  8. The carvacrol ameliorates acute pancreatitis-induced liver injury via antioxidant response.

    Science.gov (United States)

    Bakır, Murat; Geyikoglu, Fatime; Colak, Suat; Turkez, Hasan; Bakır, Tulay Ozhan; Hosseinigouzdagani, Mirkhalil

    2016-08-01

    Acute pancreatitis (AP) may cause significant persistent multi-organ dysfunction. Carvacrol (CAR) possesses a variety of biological and pharmacological properties. The aim of the present study was to analyze the hepatic protection of CAR on AP induced by cerulein and to explore the underlying mechanism using in vivo studies. The rats were randomized into groups to receive (1) no therapy; (2) 50 µg/kg cerulein at 1-h intervals by four intraperitoneal injection (i.p.); (3) 50, 100 and 200 mg/kg CAR by one i.p.; and (4) cerulein + CAR after 2 h of cerulein injection. 12 h later, serum was provided to assess the blood AST, ALT and LDH values. Also, liver tissues were obtained for histological and biochemical measurements. Liver oxidative stress markers were evaluated by changes in the amount of lipid peroxides measured as MDA and changes in tissue antioxidant enzyme levels, SOD, CAT and GSH-Px. Histopathological examination was performed using scoring systems. Oxidative damage to DNA was quantitated in studied tissues of experimental animals by measuring the increase in 8-hydroxydeoxyguanosine (8-OHdG) formations. We found that the increasing doses of CAR decreased pancreatitis-induced MDA and 8-OH-dG levels. Moreover, the liver SOD, CAT and GSH-Px activities in the AP + CAR group were higher than that of the rats in the AP group. In the treatment groups, AST, ALT and LDH were reduced. Besides, necrosis, coagulation and inflammation in the liver were alleviated (p < 0.05). We suggest that CAR could be a safe and potent new drug candidate for treating AP through its antioxidative mechanism of action for the treatment of a wide range of disorders related to hepatic dysfunction. PMID:26350272

  9. Antioxidative response to Cd in a newly discovered cadmium hyperaccumulator, Arabis paniculata F.

    Science.gov (United States)

    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

  10. Responses of bovine lymphocytes to heat shock as modified by breed and antioxidant status.

    Science.gov (United States)

    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 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. Pharmacokinetics and pharmacodynamics of phase II drug metabolizing/antioxidant enzymes gene response by anticancer agent sulforaphane in rat lymphocytes.

    Science.gov (United States)

    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

  12. A three element etched track neutron dosemeter with good angular and energy response characteristics

    International Nuclear Information System (INIS)

    A weakness of all single element etched track neutron dosemeters is that the sensitivity falls off too rapidly with increasing angle of incidence. This can lead to significant errors in practical situations. A possible solution is to incorporate in a single dosemeter one or more planar etched track detectors set at an angle to the body surface so that the sensitivity to obliquely incident neutrons is enhanced. The response of a dosemeter in which three planar elements are set in a pyramid structure is investigated. Relationships are developed which allow the response to be estimated for any given direction of incidence and any given angle between face and base of the pyramid. The results indicate that the response is close to that required to measure Hp(10) for any given direction of neutron incidence if the angle between face and base is between 30o and 40o. (author)

  13. Dynamic Stationary Response of Reinforced Plates by the Boundary Element Method

    Directory of Open Access Journals (Sweden)

    Luiz Carlos Facundo Sanches

    2007-01-01

    Full Text Available A direct version of the boundary element method (BEM is developed to model the stationary dynamic response of reinforced plate structures, such as reinforced panels in buildings, automobiles, and airplanes. The dynamic stationary fundamental solutions of thin plates and plane stress state are used to transform the governing partial differential equations into boundary integral equations (BIEs. Two sets of uncoupled BIEs are formulated, respectively, for the in-plane state (membrane and for the out-of-plane state (bending. These uncoupled systems are joined to form a macro-element, in which membrane and bending effects are present. The association of these macro-elements is able to simulate thin-walled structures, including reinforced plate structures. In the present formulation, the BIE is discretized by continuous and/or discontinuous linear elements. Four displacement integral equations are written for every boundary node. Modal data, that is, natural frequencies and the corresponding mode shapes of reinforced plates, are obtained from information contained in the frequency response functions (FRFs. A specific example is presented to illustrate the versatility of the proposed methodology. Different configurations of the reinforcements are used to simulate simply supported and clamped boundary conditions for the plate structures. The procedure is validated by comparison with results determined by the finite element method (FEM.

  14. Mycorrhizal-induced calmodulin mediated changes in antioxidant enzymes and growth response of drought-stressed trifoliate orange

    Directory of Open Access Journals (Sweden)

    Yong-Ming eHuang

    2014-12-01

    Full Text Available 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, and 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.

  15. Possible role of glutamine synthetase in the NO signaling response in root nodules by contributing to the antioxidant defenses

    Directory of Open Access Journals (Sweden)

    Liliana Santos Silva

    2013-09-01

    Full Text Available Nitric oxide (NO is emerging as an important regulatory player in the Rhizobium-legume symbiosis. The occurrence of NO during several steps of the symbiotic interaction suggests an important, but yet unknown, signaling role of this molecule for root nodule formation and functioning. The identification of the molecular targets of NO is key for the assembly of the signal transduction cascade that will ultimately help to unravel NO function. We have recently shown that the key nitrogen assimilatory enzyme Glutamine Synthetase (GS is a molecular target of NO in root nodules of Medicago truncatula, being post-translationally regulated by tyrosine nitration in relation to nitrogen fixation. In functional nodules of M. truncatula NO formation has been located in the bacteroid containing cells of the fixation zone, where the ammonium generated by bacterial nitrogenase is released to the plant cytosol and assimilated into the organic pools by plant GS. We propose that the NO-mediated GS post-translational inactivation is connected to nitrogenase inhibition induced by NO and is related to metabolite channeling to boost the nodule antioxidant defenses. Glutamate, a substrate for GS activity is also the precursor for the synthesis of glutathione (GSH, which is highly abundant in root nodules of several plant species and known to play a major role in the antioxidant defense participating in the ascorbate/GSH cycle. Existing evidence suggests that upon NO-mediated GS inhibition, glutamate could be channeled for the synthesis of GSH. According to this hypothesis, GS would be involved in the NO-signaling responses in root nodules and the NO-signaling events would meet the nodule metabolic pathways to provide an adaptive response to the inhibition of symbiotic nitrogen fixation by reactive nitrogen species (RNS.

  16. Lead detoxification by coontail (Ceratophyllum demersum L.) involves induction of phytochelatins and antioxidant system in response to its accumulation.

    Science.gov (United States)

    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

  17. Endothelial responses of magnesium and other alloying elements in magnesium-based stent materials

    Science.gov (United States)

    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

  18. Fasted and postprandial response of serum physiological response, hepatic antioxidant abilities and HSP70 expression in Wuchang bream (Megalobrama amblycephala fed different dietary carbohydrate levels

    Directory of Open Access Journals (Sweden)

    Chuanpeng Zhou

    2014-12-01

    Full Text Available The effect of dietary carbohydrate (CHO level on serum physiological response, hepatic antioxidant abilities and heat shock protein 70 (HSP70 expression of Wuchang bream (Megalobrama amblycephala was studied. Two isonitrogenous (28.56% crude protein and isolipidic (5.28% crude lipid diets were formulated to contain 30% or 53% wheat starch. Diets were fed for 90 days to fish in triplicate tanks (28 fish per tank. At the end of feeding trial, significantly higher serum triglyceride level, insulin level, cortisol level, and malondialdehyde (MDA content were observed in fish fed the 53% CHO diet, while significantly lower serum total protein content, alkaline phosphatase activity, superoxide dismutase activity and total antioxidative capacity were found in fish fed the 53% CHO diet compared with those fed the 30% diet. The relative level of hepatic heat shock protein 70 mRNA was significantly higher in the 53% CHO group than that in the 30% CHO at 6, 12 and 48 h after feeding. Ingestion of 53% dietary CHO impacts the nonspecific immune ability and causes metabolic stress in Megalobrama amblycephala.

  19. High Salinity Induces Different Oxidative Stress and Antioxidant Responses in Maize Seedlings Organs.

    Science.gov (United States)

    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

  20. High salinity induces different oxidative stress and antioxidant responses in maize seedlings organs

    Directory of Open Access Journals (Sweden)

    Hamada eAbdElgawad

    2016-03-01

    Full Text Available 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 two 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 and dehydroascorbate reductase (DHAR, increased in all organs of salt-treated plants, while superoxide dismutase (SOD, ascorbate peroxidase (APX, glutathione-s-transferase (GST and glutathione reductase (GR 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 signaling from roots to leaves, allowing leaves to activate their defense

  1. Creating Diversified Response Profiles from a Single Quenchometric Sensor Element by Using Phase-Resolved Luminescence

    Directory of Open Access Journals (Sweden)

    Elizabeth C. Tehan

    2015-01-01

    Full Text Available 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.

  2. Creating Diversified Response Profiles from a Single Quenchometric Sensor Element by Using Phase-Resolved Luminescence

    Science.gov (United States)

    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

  3. Finite element model updating of a RC building considering seismic response trends

    Science.gov (United States)

    Butt, F.; Omenzetter, P.

    2013-04-01

    This paper presents a study on the seismic response trends evaluation and finite element model updating of a reinforced concrete building monitored for a period of more than two years. The three story reinforced concrete building is instrumented with five tri-axial accelerometers and a free-field tri-axial accelerometer. The time domain N4SID system identification technique was used to obtain the frequencies and damping ratios considering flexible base models taking into account the soil-structure-interaction using 50 earthquakes. Trends of variation of seismic response were developed by correlating the peak response acceleration at the roof level with identified frequencies and damping ratios. A general trend of decreasing frequencies was observed with increased level of shaking. To simulate the varying behavior of the building with response levels, a series of three dimensional finite element models were calibrated considering several points on the developed frequency-response amplitude trend lines as targets for updating. To incorporate real in-situ conditions, soil underneath the foundation and around the building was modeled using spring elements and nonstructural components (claddings and partitions) were also included. Sensitivity based model updating technique was applied taking into account concrete, soil and cladding stiffness as updating parameters. It was concluded from the investigation that knowledge of the variation of seismic response of buildings is necessary to better understand their behavior during earthquakes, and also that the participation of soil and non-structural components is significant towards the seismic response of the building and these should be considered in models to simulate the real behavior.

  4. Ultraviolet-B light induced oxidative stress: effects on antioxidant response of Spodoptera litura.

    Science.gov (United States)

    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. PMID:24792567

  5. Antioxidant enzyme level response to prooxidant allelochemicals in larvae of the southern armyworm moth, Spodoptera eridania.

    Science.gov (United States)

    Pritsos, C A; Ahmad, S; Elliott, A J; Pardini, R S

    1990-01-01

    Larvae of the southern armyworm, Spodoptera eridania, are highly polyphagous feeders which frequently encounter and feed upon plants containing high levels of prooxidant allelochemicals. While ingestion of moderate quantities of prooxidants can be tolerated by these larvae, ingestion of larger quantities can result in toxicity. Studies were conducted to assess the role of the antioxidant enzymes, superoxide dismutase (SOD), catalase (CAT) and glutathione reductase (GR) in the protection of S. eridania against redox active prooxidant plant allelochemicals. Dietary exposure of mid-fifth-instar larvae to either quercetin (a flavonoid) or xanthotoxin (a photoactive furanocoumarin), which generate superoxide radical, and singlet oxygen, respectively, resulted in an increase in SOD levels. CAT levels increased in all groups of S. eridania including control insects. This may have been due to the sudden exposure to food following an extended fast of 18 h (to insure that larvae would not reject the diet because of the prooxidants' bitter taste) with an eventual lowering of CAT values with time. GR activities did not significantly change except for a slight inhibition at the highest prooxidant concentrations used at 12-h post-ingestion. The data from these studies suggest that SOD responds to prooxidant challenges in these insects and together with CAT and GR contributes to the insect's defense against potentially toxic prooxidant compounds. PMID:2161387

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

    Science.gov (United States)

    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 (pcarbofuran-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 (p0.05) in gonads of treated fish. The two metabolic enzymes G6PDH and LDH in all tissues exhibited significant decreases (pcarbofuran. LPO levels increased significantly (pcarbofuran. There was a significant (pcarbofuran 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.

  7. Sodium tungstate induced neurological alterations in rat brain regions and their response to antioxidants.

    Science.gov (United States)

    Sachdeva, Sherry; Pant, Satish C; Kushwaha, Pramod; Bhargava, Rakesh; Flora, Swaran J S

    2015-08-01

    Tungsten, recognized recently as an environmental contaminant, is being used in arms and ammunitions as substitute to depleted uranium. We studied the effects of sodium tungstate on oxidative stress, few selected neurological variables like acetylcholinesterase, biogenic amines in rat brain regions (cerebral cortex, hippocampus and cerebellum) and their prevention following co-administration of N-acetylcysteine (NAC), naringenin and quercetin. Animals were sub-chronically exposed to sodium tungstate (100 ppm in drinking water) and orally co-supplemented with different antioxidants (0.30 mM) for three months. Sodium tungstate significantly decreased the activity of acetylcholinesterase, dopamine, nor-epinephrine and 5-hydroxytryptamine levels while it increased monoamine oxidase activity in different brain regions. Tungstate exposure produced a significant increase in biochemical variables indicative of oxidative stress while, neurological alterations were more pronounced in the cerebral cortex compared to other regions. Co-administration of NAC and flavonoids with sodium tungstate significantly restored glutathione, prevented changes in the brain biogenic amines, reactive oxygen species (ROS) and TBARS levels in the different brain regions. The protection was more prominent in the animals co-administered with NAC. We can thus conclude that sodium tungstate induced brain oxidative stress and the alterations in some neurological variables can effectively be reduced by co-supplementation of NAC. PMID:25983264

  8. Antioxidant responses and salt stress tolerance of Aloe vera irrigated by seawater with different salinity

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    The variations of antioxidant enzyme activities including superoxide dismutase (SOD: EC 1.15.1.1), peroxidase (POD: EC 1.11.1.7) and catalase (CAT: EC 1.11.1.6), lipid peroxidation and major electrolytes in Aloe vera irrigated for three years with seawater having different salinity were studied. The results indicate that POD activity increased significantly at 10% seawater level, whereas decreased at higher seawater levels. The SOD activity decreased with increasing seawater concentration except for treatment with 100% seawater (denoted as T100% ) under long-term salt stress. Salinity decreased CATactivity,and increased lipid peroxidation and cell membrane injury. In addition, Ca2+ content was high in Aloe irrigated by seawater of low salinity level, but low in Aloe irrigated by seawater of high salinity level. An opposite trend was observed for the effect of seawater on Na + content of plants. K + and Mg2 +contents remain relatively stable under various seawater levels, which benefit plant growth.

  9. Effects of light intensity on growth, immune responses, antioxidant capability and disease resistance of juvenile blunt snout bream Megalobrama amblycephala.

    Science.gov (United States)

    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

  10. An Extended Finite Element Method Formulation for Modeling the Response of Polycrystalline Materials to Dynamic Loading

    Science.gov (United States)

    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.

  11. Antioxidative responses of the tissues of two wild populations of Pelophylax kl. esculentus frogs to heavy metal pollution.

    Science.gov (United States)

    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

  12. Low Root Zone Temperature Exacerbates the Ion Imbalance and Photosynthesis Inhibition and Induces Antioxidant Responses in Tomato Plants Under Salinity

    Institute of Scientific and Technical Information of China (English)

    HE Yong; YANG Jing; ZHU Biao; ZHU Zhu-jun

    2014-01-01

    The combined effects of salinity with low root zone temperature (RZT) on plant growth and photosynthesis were studied in tomato (Solanum lycopersicum) plants. The plants were exposed to two different root zone temperatures (28/20°C, 12/8°C, day/night temperature) in combination with two NaCl levels (0 and 100 mmol L-1). After 2 wk of treatment, K+and Na+ concentration, leaf photosynthetic gas exchange, chlorophyll lfuorescence and leaf antioxidant enzyme activities were measured. Salinity signiifcantly decreased plant biomass, net photosynthesis rate, actual quantum yield of photosynthesis and concentration of K+, but remarkably increased the concentration of Na+. These effects were more pronounced when the salinity treatments were combined with the treatment of low RZT conditions. Either salinity or low RZT individually did not affect maximal efifciency of PSII photochemistry (Fv/Fm), while a combination of these two stresses decreased Fv/Fm considerably, indicating that the photo-damage occurred under such conditions. Non-photochemical quenching was increased by salt stress in accompany with the enhancement of the de-epoxidation state of the xanthophyll cycle, in contrast, this was not the case with low RZT applied individually. Salinity stress individually increased the activities of SOD, APX, GPOD and GR, and decreased the activities of DHAR. Due to the interactive effects of salinity with low RZT, these ifve enzyme activities increased sharply in the combined stressed plants. These results indicate that low RZT exacerbates the ion imbalance, PSII damage and photosynthesis inhibition in tomato plants under salinity. In response to the oxidative stress under salinity in combination with low RZT, the activities of antioxidant enzymes SOD, APX, GPOD, DHAR and GR were clearly enhanced in tomato plants.

  13. Response of the physiological parameters of mango fruit (transpiration, water relations and antioxidant system) to its light and temperature environment.

    Science.gov (United States)

    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

  14. Effects of friction on the unconfined compressive response of articular cartilage: a finite element analysis.

    Science.gov (United States)

    Spilker, R L; Suh, J K; Mow, V C

    1990-05-01

    A finite element analysis is used to study a previously unresolved issue of the effects of platen-specimen friction on the response of the unconfined compression test; effects of platen permeability are also determined. The finite element formulation is based on the linear KLM biphasic model for articular cartilage and other hydrated soft tissues. A Galerkin weighted residual method is applied to both the solid phase and the fluid phase, and the continuity equation for the intrinsically incompressible binary mixture is introduced via a penalty method. The solid phase displacements and fluid phase velocities are interpolated for each element in terms of unknown nodal values, producing a system of first order differential equations which are solved using a standard numerical finite difference technique. An axisymmetric element of quadrilateral cross-section is developed and applied to the mechanical test problem of a cylindrical specimen of soft tissue in unconfined compression. These studies show that interfacial friction plays a major role in the unconfined compression response of articular cartilage specimens with small thickness to diameter ratios. PMID:2345443

  15. Mineral elements of subtropical tree seedlings in response to elevated carbon dioxide and nitrogen addition.

    Directory of Open Access Journals (Sweden)

    Wenjuan Huang

    Full Text Available 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.

  16. Verification of Advective Bar Elements Implemented in the Aria Thermal Response Code.

    Energy Technology Data Exchange (ETDEWEB)

    Mills, Brantley [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

    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.

  17. An extended finite element formulation for modeling the response of polycrystalline materials to shock loading

    Science.gov (United States)

    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.)

  18. Optimization of Extraction Condition of Bee Pollen Using Response Surface Methodology: Correlation between Anti-Melanogenesis, Antioxidant Activity, and Phenolic Content

    Directory of Open Access Journals (Sweden)

    Seon Beom Kim

    2015-11-01

    Full Text Available 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.

  19. Finite element response sensitivity and reliability analysis of Soil-Foundation-Structure-Interaction (SFSI) systems

    OpenAIRE

    Gu, Quan

    2008-01-01

    Performance-based earthquake engineering (PBEE) has emerged as a powerful method of analysis and design philosophy in earthquake engineering and is leading the way to a new generation of seismic design guidelines. PBEE requires a comprehensive understanding of the earthquake response of Soil-Foundation-Structure-Interaction (SFSI) systems when damage occurs in the structural system during the earthquake. In the context of PBEE, this research combines finite element (FE) modeling and seismic r...

  20. Farnesoid X Receptor Inhibits the Transcriptional Activity of Carbohydrate Response Element Binding Protein in Human Hepatocytes

    OpenAIRE

    Caron, Sandrine; Huaman Samanez, Carolina; Dehondt, Hélène; Ploton, Maheul; Briand, Olivier; Lien, Fleur; Dorchies, Emilie; Dumont, Julie; Postic, Catherine; Cariou, Bertrand; Lefebvre, Philippe; Staels, Bart

    2013-01-01

    The glucose-activated transcription factor carbohydrate response element binding protein (ChREBP) induces the expression of hepatic glycolytic and lipogenic genes. The farnesoid X receptor (FXR) is a nuclear bile acid receptor controlling bile acid, lipid, and glucose homeostasis. FXR negatively regulates hepatic glycolysis and lipogenesis in mouse liver. The aim of this study was to determine whether FXR regulates the transcriptional activity of ChREBP in human hepatocytes and to unravel the...

  1. What type of controlling investors impact on which elements of corporate social responsibility?

    OpenAIRE

    Rees, William; Rodionova, Tatiana

    2012-01-01

    Using a large sample of 3541 companies drawn from 30 countries over a period from 2002 to 2010, we analysed the impact of strategic shareholdings on different elements of corporate social responsibility (CSR). We find that total strategic or closely held equity holdings adversely affect the environmental, social and governance scores provided by ASSET4. However, this effect is largely driven by entrenched and undiversified holdings such as family and corporate cross-holdings, whereas diversif...

  2. Finite element simulation for mechanical response of surface mounted solder joints under different temperature cycling

    Institute of Scientific and Technical Information of China (English)

    马鑫; 钱乙余

    2001-01-01

    Nonlinear finite element simulation for mechanical response of surface mounted solder joint under different temperature cycling was carried out. Seven sets of parameters were used in order to evaluate the influence of temperature cycling profile parameters. The results show that temperature cycling history has significant effect on the stress response of the solder joint. Based on the concept of relative damage stress proposed by the authors, it is found that enough high temperature holding time is necessary for designing the temperature cycling profile in accelerated thermal fatigue test.

  3. Isolation of transcription factors binding auxin response elements using a yeast one-hybrid system

    Institute of Scientific and Technical Information of China (English)

    QI; Mei(齐眉); HUANG; Meijuan(黄美娟); CHEN; Fan(陈凡)

    2002-01-01

    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.

  4. Three-dimensional dynamic response modelling for floating nuclear power plants using finite element methods

    International Nuclear Information System (INIS)

    A modelling technique which can be used to obtain the dynamic response of a floating nuclear plant (FNP) moored in an artificial basin is presented. Hydrodynamic effects of the seawater in the basin have a significant impact on the response of the FNP and must be included. A three dimensional model of the platform and mooring system (using beam elements) is used, with the hydrodynamic effects represented by added mass and damping. For an essentially square plant in close proximity to the site structures, the three dimensional nature of the basin must be considered in evaluating the added mass and damping. A method for estimating these effects from planer finite element analyses is developed. The accuracy of the planar finite element model in obtaining two-dimensional added mass and damping is shown through comparison with existing the documented results. In addition, a comparison is shown for open ocean added mass and damping with a three-dimensional solution using velocity potential functions. It is concluded that the overall technique results in a reasonable and conservative calculation of the dynamic response of the floating nuclear plant. (orig./HP)

  5. Development of a Rapidly Deployed Department of Energy Emergency Response Element

    International Nuclear Information System (INIS)

    The Federal Radiological Emergency Response Plan (FRERP) directs the Department of Energy (DOE) to maintain a viable, timely, and fully documented response option capable of supporting the responsible Lead Federal Agency in the event of a radiological emergency impacting any state or US territory (e.g., CONUS). In addition, the DOE maintains a response option to support radiological emergencies outside the continental US (OCONUS). While the OCUNUS mission is not governed by the FREP, this response is operationally similar to that assigned to the DOE by the FREP. The DOE is prepared to alert, activate, and deploy radiological response teams to augment the Radiological Assistance Program and/or local responders. The Radiological Monitoring and Assessment Center (RMAC) is a phased response that integrates with the Federal Radiological Monitoring and Assessment Center (FRMAC) in CONUS environments and represents a stand-alone DOE response for OCONUS environments. The FRMAC/RMAC Phase I was formally ''stood up'' as an operational element in April 1999. The FRMAC/RMAC Phase II proposed ''stand-up'' date is midyear 2000

  6. Chronic stress differentially affects antioxidant enzymes and modifies the acute stress response in liver of Wistar rats.

    Science.gov (United States)

    Djordjevic, J; Djordjevic, A; Adzic, M; Niciforovic, A; Radojcic, M B

    2010-01-01

    Clinical reports suggest close interactions between stressors, particularly those of long duration, and liver diseases, such as hepatic inflammation, that is proposed to occur via reactive oxygen species. In the present study we have used 21-day social isolation of male Wistar rats as a model of chronic stress to investigate protein expression/activity of liver antioxidant enzymes: superoxide dismutases (SODs), catalase (CAT), glutathione peroxidase (GPx) and glutathione reductase (GLR), and protein expression of their upstream regulators: glucocorticoid receptor (GR) and nuclear factor kappa B (NFkB). We have also characterized these parameters in either naive or chronically stressed animals that were challenged by 30-min acute immobilization. We found that chronic isolation caused decrease in serum corticosterone (CORT) and blood glucose (GLU), increase in NFkB signaling, and disproportion between CuZnSOD, peroxidases (CAT, GPx) and GLR, thus promoting H2O2 accumulation and prooxidative state in liver. The overall results suggested that chronic stress exaggerated responsiveness to subsequent stressor at the level of CORT and GLU, and potentiated GLR response, but compromised the restoration of oxido-reductive balance due to irreversible alterations in MnSOD and GPx. PMID:20406049

  7. Antioxidant Capacity of Flavonoids in Hepatic Microsomes Is not Reflected by Antioxidant Effects In Vivo

    Directory of Open Access Journals (Sweden)

    Garry Duthie

    2012-01-01

    Full Text Available Flavonoids are polyphenolic compounds with potential antioxidant activity via multiple reduction capacities. Oxidation of cellular lipids has been implicated in many diseases. Consequently, this study has assessed the ability of several dietary flavonoid aglycones to suppress lipid peroxidation of hepatic microsomes derived from rats deficient in the major lipid soluble antioxidant, dα-tocopherol. Antioxidant effectiveness was galangin > quercetin > kaempferol > fisetin > myricetin > morin > catechin > apigenin. However, none of the flavonoids were as effective as dα-tocopherol, particularly at the lowest concentrations used. In addition, there appears to be an important distinction between the in vitro antioxidant effectiveness of flavonoids and their ability to suppress indices of oxidation in vivo. Compared with dα-tocopherol, repletion of vitamin E deficient rats with quercetin, kaempferol, or myricetin did not significantly affect indices of lipid peroxidation and tissue damage. Direct antioxidant effect of flavonoids in vivo was not apparent probably due to low bioavailability although indirect redox effects through stimulation of the antioxidant response element cannot be excluded.

  8. Equivalent Dynamic Stiffness Mapping technique for identifying nonlinear structural elements from frequency response functions

    Science.gov (United States)

    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.

  9. Roles of the host oxidative immune response and bacterial antioxidant rubrerythrin during Porphyromonas gingivalis infection.

    Directory of Open Access Journals (Sweden)

    Piotr Mydel

    2006-07-01

    Full Text Available The efficient clearance of microbes by neutrophils requires the concerted action of reactive oxygen species and microbicidal components within leukocyte secretory granules. Rubrerythrin (Rbr is a nonheme iron protein that protects many air-sensitive bacteria against oxidative stress. Using oxidative burst-knockout (NADPH oxidase-null mice and an rbr gene knockout bacterial strain, we investigated the interplay between the phagocytic oxidative burst of the host and the oxidative stress response of the anaerobic periodontal pathogen Porphyromonas gingivalis. Rbr ensured the proliferation of P. gingivalis in mice that possessed a fully functional oxidative burst response, but not in NADPH oxidase-null mice. Furthermore, the in vivo protection afforded by Rbr was not associated with the oxidative burst responses of isolated neutrophils in vitro. Although the phagocyte-derived oxidative burst response was largely ineffective against P. gingivalis infection, the corresponding oxidative response to the Rbr-positive microbe contributed to host-induced pathology via potent mobilization and systemic activation of neutrophils. It appeared that Rbr also provided protection against reactive nitrogen species, thereby ensuring the survival of P. gingivalis in the infected host. The presence of the rbr gene in P. gingivalis also led to greater oral bone loss upon infection. Collectively, these results indicate that the host oxidative burst paradoxically enhances the survival of P. gingivalis by exacerbating local and systemic inflammation, thereby contributing to the morbidity and mortality associated with infection.

  10. The importance of antioxidants which play the role in cellular response against oxidative/nitrosative stress: current state.

    Science.gov (United States)

    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

  11. Validation of an interferon stimulatory response element reporter gene assay for quantifying type I interferons.

    Science.gov (United States)

    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.

  12. Expression analysis of antioxidant genes in response to drought stress in the fl ag leaf of two Indonesian rice cultivars

    Directory of Open Access Journals (Sweden)

    Refli R

    2015-12-01

    Full Text Available The objective of this study was to analysis the expression of antioxidant genes in response to droughtstress in Indonesian rice. The malondialdehyde (MDA content and the expression of Cu-ZnSod1, cCu-ZnSod2,MnSod1, cApxa, cApxb, chl-sApx, Cat1, Cat2, Cat3, Gr1, Gr2, and Gr3 genes were assayed in the rice fl ag leaf ofCiherang and Situ Bagendit cultivars subjected to control, mild and severe drought during the grain fi llingphase. Increase in MDA content of Ciherang treated to mild and severe drought was almost two-fold andthree-fold respectively, while MDA content in Situ Bagendit subjected to mild and severe drought increasedapproximately one-fold and two-fold as compared to the control. The semi quantitative reverse transcriptionpolymerase chain reaction (sqRT-PCR analysis showed that the expression of cCu-ZnSod1, MnSod1, Cat2, Gr3genes of Ciherang, and cCu-ZnSod2, MnSod1, cApxa, cApxb, chl-sAPX, Cat2 and Gr1 genes of Situ Bagendit increasedin fl ag leaf of plant treated to drought. Expressions of cApxb, chl-sApx, Cat3 of Ciherang and Cu-ZnSod1 and Gr2genes of Situ Bagendit were not changed signifi cantly by drought stress. Decreased expression was shownby cCu-ZnSod2, cApxa, Cat1, Gr1 and Gr2 genes of Ciherang, and Cat1, Cat3 and Gr3 genes of Situ Bagendit. Theresults indicated that the activity of oxidative defense was regulated by four genes; cCu-ZnSod1, MnSod1, Cat2,Gr3 in Ciherang, and eight genes; cCu-ZnSod1, cCu-ZnSod2, MnSod1, cApxa, cApxb, chl-sApx, Cat2 and Gr1 in SituBagendit. Therefore, differences in the number of antioxidant genes controlling oxidative defense systemmight determine the difference of the oxidative defense capacity between both cultivars in response to droughtstress during grain fi lling.

  13. Effects of in ovo injection with selenium on immune and antioxidant responses during experimental necrotic enteritis in broiler chickens.

    Science.gov (United States)

    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

  14. 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.

    Science.gov (United States)

    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

  15. Allergic sensitization is associated with inadequate anti-oxidant responses in mice and men

    NARCIS (Netherlands)

    Utsch, Lara; Folisi, Caterina; Akkerdaas, Jaap H; Logiantara, Adrian; van de Pol, Marianne A; van der Zee, Jaring S; Krop, Esmeralda J M; Lutter, René; van Ree, Ronald; van Rijt, Leonie S

    2015-01-01

    BACKGROUND: Allergies arise from aberrant Th2 responses to allergens. The processes involved in the genesis of allergic sensitization remain elusive. Some allergens such as derived from house dust mites, have proteolytic activity which can induce oxidative stress in vivo. A reduced capacity of the h

  16. Analysis of Resonance Response Performance of C-Band Antenna Using Parasitic Element

    Directory of Open Access Journals (Sweden)

    M. R. Zaman

    2014-01-01

    Full Text Available 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.

  17. Two-Dimensional Finite Element Ablative Thermal Response Analysis of an Arcjet Stagnation Test

    Science.gov (United States)

    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.

  18. AN ENHANCED ELEMENT-FREE GALERKIN METHOD FOR DYNAMIC RESPONSE OF POROELASTIC SEABED

    Institute of Scientific and Technical Information of China (English)

    HUA Lei-na; YU Xi-ping

    2009-01-01

    This study presents an effective numerical model for the dynamic response of poroelastic seabed under wave action with enhanced performance. The spatial discretization is based on the Element-Free Galerkin (EFG) method and the time integration based on the GN11 scheme. A stability strategy that adopts a smaller number of nodes for the pore water pressure compared with those for the displacements of the soil skeleton is suggested to resolve the similar difficulty as encountered in the finite element method for a problem with mixed formulation when the pore water is incompressible and the soil skeleton impervious. The accuracy of the numerical model is verified through applying it to a typical case with critical permeability. Good agreement between computational and analytical solutions is obtained.

  19. Identification of peroxisome-proliferator responsive element in the mouse HSL gene.

    Science.gov (United States)

    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.

  20. Identification of two novel functional p53 responsive elements in the Herpes Simplex Virus-1 genome

    OpenAIRE

    Hsieh, Jui-Cheng; Kuta, Ryan; Armour, Courtney R.; Boehmer, Paul E.

    2014-01-01

    Analysis of the herpes simplex virus-1 (HSV-1) genome reveals two candidate p53 responsive elements (p53RE), located in proximity to the replication origins oriL and oriS, referred to as p53RE-L and p53RE-S, respectively. The sequences of p53RE-L and p53RE-S conform to the p53 consensus site and are present in HSV-1 strains KOS, 17, and F. p53 binds to both elements in vitro and in virus-infected cells. Both p53RE-L and p53RE-S are capable of conferring p53-dependent transcriptional activatio...

  1. Finite element simulation of rate-dependent magneto-active polymer response

    Science.gov (United States)

    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.

  2. Genomic Regulation of the Response of an Agroecosystem to Elements of Global Change

    Energy Technology Data Exchange (ETDEWEB)

    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.

  3. Response of testicular antioxidant enzymes to hexachlorocy—clohexane is species specific

    Institute of Scientific and Technical Information of China (English)

    LunaSamanta; G·B·N·Chainy

    2002-01-01

    Aim:To find out whether the response of testicular oxidative stess parameters to hexachlorocyclohexane(HCH)is species specific.Methods:In rats and mice(n=5in each group).HCHwas administered at a dose of 20mg/kg/day intraperitoneally for 30daysin0.1ml of refined rgoundnut oil.The control groups received equal volume of the vehicle.Animals were sacrificed 24hours after the last injection and various oxidative stress parameters were measured immediately.Results:The level of both endogenous as well as FeSO4and ascorbic acid-stimulated lipid peroxidation was increased significantly in the HCH-treated rats,whereas the pattern was just the reverse in case of mice.Although the level of H2O2content increased inresponse to HCHinboth groups,a totally different trend was observed for the activity of the principal H2O2-metabolising emzyme,catalase,In case of rats,a significant decline inthe activity of catalase was recorded in response to HCH whereas a sharp augmentation in the enzyme activity was noticed im mice,Similarly,the decreased activity of superoxide dismutase observed in rast remained unaltered in mice.Conclusion:HCH induces oxidative stress in the testis of both rats and mice,However,the pattern of response of testicular oxidative stress parameters seems to be species specific.

  4. Optimization extraction of polysaccharide from Tunisian Zizyphus lotus fruit by response surface methodology: Composition and antioxidant activity.

    Science.gov (United States)

    Mkadmini Hammi, Khaoula; Hammami, Majdi; Rihouey, Christophe; Le Cerf, Didier; Ksouri, Riadh; Majdoub, Hatem

    2016-12-01

    Response surface methodology using a Box-Behnken design was employed to optimize extraction temperature, extraction time and ratio of water to material to obtain a maximum polysaccharide yield with high uronic acid content and antioxidant property from edible Zizyphus lotus fruit. The optimal conditions were: extraction time of 3h 15min, extraction temperature of 91.2°C and water to solid ratio of 39mL/g. Under these conditions, the experimental extraction yield, uronic acid content and 2,2-diphenyl-1-picrylhydrazyl scavenging ability (IC50) were 18.88%, 41.89 and 0.518mg/mL, respectively. Chemical analysis revealed that the extract was composed of 97.92% carbohydrate of which 41.89% is uronic acid. The extracted polysaccharides, with an average molecular weight of 2720kDa, are composed of arabinose, rhamnose, glucose, fructose, galactose and xylose. Moreover, the polysaccharides exhibited a significant reducing power and anti-lipid peroxidation activities.

  5. Effects of Pb on the oxidative stress and antioxidant response in a Pb bioaccumulator plant Vallisneria natans.

    Science.gov (United States)

    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

  6. Optimization extraction of polysaccharide from Tunisian Zizyphus lotus fruit by response surface methodology: Composition and antioxidant activity.

    Science.gov (United States)

    Mkadmini Hammi, Khaoula; Hammami, Majdi; Rihouey, Christophe; Le Cerf, Didier; Ksouri, Riadh; Majdoub, Hatem

    2016-12-01

    Response surface methodology using a Box-Behnken design was employed to optimize extraction temperature, extraction time and ratio of water to material to obtain a maximum polysaccharide yield with high uronic acid content and antioxidant property from edible Zizyphus lotus fruit. The optimal conditions were: extraction time of 3h 15min, extraction temperature of 91.2°C and water to solid ratio of 39mL/g. Under these conditions, the experimental extraction yield, uronic acid content and 2,2-diphenyl-1-picrylhydrazyl scavenging ability (IC50) were 18.88%, 41.89 and 0.518mg/mL, respectively. Chemical analysis revealed that the extract was composed of 97.92% carbohydrate of which 41.89% is uronic acid. The extracted polysaccharides, with an average molecular weight of 2720kDa, are composed of arabinose, rhamnose, glucose, fructose, galactose and xylose. Moreover, the polysaccharides exhibited a significant reducing power and anti-lipid peroxidation activities. PMID:27374558

  7. The Effects of Cadmium Exposure on Fitness-Related Traits and Antioxidant Responses in the Wolf Spider, Pardosa pseudoannulata.

    Science.gov (United States)

    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

  8. Altered response hierarchy and increased T-cell breadth upon HIV-1 conserved element DNA vaccination in macaques.

    Directory of Open Access Journals (Sweden)

    Viraj Kulkarni

    Full Text Available HIV sequence diversity and potential decoy epitopes are hurdles in the development of an effective AIDS vaccine. A DNA vaccine candidate comprising of highly conserved p24(gag elements (CE induced robust immunity in all 10 vaccinated macaques, whereas full-length gag DNA vaccination elicited responses to these conserved elements in only 5 of 11 animals, targeting fewer CE per animal. Importantly, boosting CE-primed macaques with DNA expressing full-length p55(gag increased both magnitude of CE responses and breadth of Gag immunity, demonstrating alteration of the hierarchy of epitope recognition in the presence of pre-existing CE-specific responses. Inclusion of a conserved element immunogen provides a novel and effective strategy to broaden responses against highly diverse pathogens by avoiding decoy epitopes, while focusing responses to critical viral elements for which few escape pathways exist.

  9. Growth Responses and Leaf Antioxidant Metabolism of Grass Pea (Lathyrus sativus L.) Genotypes under Salinity Stress

    OpenAIRE

    Dibyendu Talukdar

    2013-01-01

    Response of six improved grass pea genotypes to prolonged salinity stress was investigated on seedlings grown in pot experiment using 150 mM NaCl up to 60 days of growth after commencement of treatment (DAC). NaCl exposure significantly reduced growth potential of varieties PUSA-90-2 and WBK-CB-14, but no such effect was observed in varieties B1, BioL-212 and in two mutant lines LR3 and LR4. A time-bound measurement at 15, 30 and 60 DAC revealed significant reduction in plant dry matter produ...

  10. Flavonoids Extraction from Taraxacum officinale (Dandelion): Optimisation Using Response Surface Methodology and Antioxidant Activity

    OpenAIRE

    Zongxi Sun; Ruiqiang Su; Jianwei Qiao; Zhiquan Zhao; Xinsheng Wang

    2014-01-01

    The Box-Behnken design combined with response surface method was employed to optimize ultrasonic-assisted extraction of flavonoids from Taraxacum officinale. The optimized results showed that the highest extraction yield with ultrasonic-assisted extraction could reach 2.62% using 39.6% (v/v) ethanol and 59.5 : 1 (mL/g) liquid-solid ratio for 43.8 min. The crude extract was then purified by HPD-100 macroporous adsorption resin, and the flavonoids content in the purified extract increased to 54...

  11. Differential interactions of promoter elements in stress responses of the Arabidopsis Adh gene.

    Science.gov (United States)

    Dolferus, R; Jacobs, M; Peacock, W J; Dennis, E S

    1994-01-01

    The Adh (alcohol dehydrogenase, EC 1.1.1.1.) gene from Arabidopsis thaliana (L.) Heynh. can be induced by dehydration and cold, as well as by hypoxia. A 1-kb promoter fragment (CADH: -964 to +53) is sufficient to confer the stress induction and tissue-specific developmental expression characteristics of the Adh gene to a beta-glucuronidase reporter gene. Deletion mapping of the 5' end and site-specific mutagenesis identified four regions of the promoter essential for expression under the three stress conditions. Some sequence elements are important for response to all three stress treatments, whereas others are stress specific. The most critical region essential for expression of the Arabidopsis Adh promoter under all three environmental stresses (region IV: -172 to -141) contains sequences homologous to the GT motif (-160 to -152) and the GC motif (-147 to -144) of the maize Adh1 anaerobic responsive element. Region III (-235 to -172) contains two regions shown by R.J. Ferl and B.H. Laughner ([1989] Plant Mol Biol 12: 357-366) to bind regulatory proteins; mutation of the G-box-1 region (5'-CCACGTGG-3', -216 to -209) does not affect expression under uninduced or hypoxic conditions, but significantly reduces induction by cold stress and, to a lesser extent, by dehydration stress. Mutation of the other G-box-like sequence (G-box-2: 5'-CCAAGTGG-3', -193 to -182) does not change hypoxic response and affects cold and dehydration stress only slightly. G-box-2 mutations also promote high levels of expression under uninduced conditions. Deletion of region I (-964 to -510) results in increased expression under uninduced and all stress conditions, suggesting that this region contains a repressor binding site. Region II (-510 to -384) contains a positive regulatory element and is necessary for high expression levels under all treatments. PMID:7972489

  12. Oxidative and antioxidative responses in the wheat-Azospirillum brasilense interaction.

    Science.gov (United States)

    Méndez-Gómez, Manuel; Castro-Mercado, Elda; Alexandre, Gladys; García-Pineda, Ernesto

    2016-03-01

    Azospirillum is a plant growth-promoting rhizobacteria (PGPR) able to enhance the growth of wheat. The aim of this study was to test the effect of Azospirillum brasilense cell wall components on superoxide (O2·(-)) production in wheat roots and the effect of oxidative stress on A. brasilense viability. We found that inoculation with A. brasilense reduced O2·(-) levels by approx. 30 % in wheat roots. Inoculation of wheat with papain-treated A. brasilense, a Cys protease, notably increased O2·(-) production in all root tissues, as was observed by the nitro blue tetrazolium (NBT) reduction. However, a 24-h treatment with rhizobacteria lipopolysaccharides (50 and 100 μg/mL) alone did not affect the pattern of O2·(-) production. Analysis of the effect of plant cell wall components on A. brasilense oxidative enzyme activity showed no changes in catalase activity but a decrease in superoxide dismutase activity in response to polygalacturonic acid treatment. Furthermore, A. brasilense growth was only affected by high concentrations of H2O2 or paraquat, but not by sodium nitroprusside. Our results suggest that rhizobacterial cell wall components play an important role in controlling plant cell responses and developing tolerance of A. brasilense to oxidative stress produced by the plant.

  13. Oxidative and antioxidative responses in the wheat-Azospirillum brasilense interaction.

    Science.gov (United States)

    Méndez-Gómez, Manuel; Castro-Mercado, Elda; Alexandre, Gladys; García-Pineda, Ernesto

    2016-03-01

    Azospirillum is a plant growth-promoting rhizobacteria (PGPR) able to enhance the growth of wheat. The aim of this study was to test the effect of Azospirillum brasilense cell wall components on superoxide (O2·(-)) production in wheat roots and the effect of oxidative stress on A. brasilense viability. We found that inoculation with A. brasilense reduced O2·(-) levels by approx. 30 % in wheat roots. Inoculation of wheat with papain-treated A. brasilense, a Cys protease, notably increased O2·(-) production in all root tissues, as was observed by the nitro blue tetrazolium (NBT) reduction. However, a 24-h treatment with rhizobacteria lipopolysaccharides (50 and 100 μg/mL) alone did not affect the pattern of O2·(-) production. Analysis of the effect of plant cell wall components on A. brasilense oxidative enzyme activity showed no changes in catalase activity but a decrease in superoxide dismutase activity in response to polygalacturonic acid treatment. Furthermore, A. brasilense growth was only affected by high concentrations of H2O2 or paraquat, but not by sodium nitroprusside. Our results suggest that rhizobacterial cell wall components play an important role in controlling plant cell responses and developing tolerance of A. brasilense to oxidative stress produced by the plant. PMID:25952083

  14. Spatially dependent burnup implementation into the nodal program based on the finite element response matrix method

    International Nuclear Information System (INIS)

    In this work a spatial burnup scheme and feedback effects has been implemented into the FERM ( 'Finite Element Response Matrix' )program. The spatially dependent neutronic parameters have been considered in three levels: zonewise calculation, assembly wise calculation and pointwise calculation. Flux and power distributions and the multiplication factor were calculated and compared with the results obtained by CITATIOn program. These comparisons showed that processing time in the Ferm code has been hundred of times shorter and no significant difference has been observed in the assembly average power distribution. (Author)

  15. On the structure of AP-4 responsive element in the LTR of Jembrana disease virus

    Institute of Scientific and Technical Information of China (English)

    2003-01-01

    Previous studies with deletion and sequence analysis of JDV LTR showed that there is a putative AP-4 responsive element in LTR. By antisense transient assay and gel shifting assay, we for the first time demonstrated that AP-4 modulated JDV gene expression by binding DNA directly to bovine cells. The results, derived from site-directed mutagenesis experiments, suggest that the six base pairs of AP-4 binding site (CAGCTG) have different effects on JDV gene expression. When the first two base pairs changed to GC, JDV gene expression is severely decreased.

  16. Trichoderma-plant root colonization: escaping early plant defense responses and activation of the antioxidant machinery for saline stress tolerance.

    Science.gov (United States)

    Brotman, Yariv; Landau, Udi; Cuadros-Inostroza, Álvaro; Tohge, Takayuki; Takayuki, Tohge; Fernie, Alisdair R; Chet, Ilan; Viterbo, Ada; Willmitzer, Lothar

    2013-03-01

    Trichoderma spp. are versatile opportunistic plant symbionts which can colonize the apoplast of plant roots. Microarrays analysis of Arabidopsis thaliana roots inoculated with Trichoderma asperelloides T203, coupled with qPCR analysis of 137 stress responsive genes and transcription factors, revealed wide gene transcript reprogramming, proceeded by a transient repression of the plant immune responses supposedly to allow root colonization. Enhancement in the expression of WRKY18 and WRKY40, which stimulate JA-signaling via suppression of JAZ repressors and negatively regulate the expression of the defense genes FMO1, PAD3 and CYP71A13, was detected in Arabidopsis roots upon Trichoderma colonization. Reduced root colonization was observed in the wrky18/wrky40 double mutant line, while partial phenotypic complementation was achieved by over-expressing WRKY40 in the wrky18 wrky40 background. On the other hand increased colonization rate was found in roots of the FMO1 knockout mutant. Trichoderma spp. stimulate plant growth and resistance to a wide range of adverse environmental conditions. Arabidopsis and cucumber (Cucumis sativus L.) plants treated with Trichoderma prior to salt stress imposition show significantly improved seed germination. In addition, Trichoderma treatment affects the expression of several genes related to osmo-protection and general oxidative stress in roots of both plants. The MDAR gene coding for monodehydroascorbate reductase is significantly up-regulated and, accordingly, the pool of reduced ascorbic acid was found to be increased in Trichoderma treated plants. 1-Aminocyclopropane-1-carboxylate (ACC)-deaminase silenced Trichoderma mutants were less effective in providing tolerance to salt stress, suggesting that Trichoderma, similarly to ACC deaminase producing bacteria, can ameliorate plant growth under conditions of abiotic stress, by lowering ameliorating increases in ethylene levels as well as promoting an elevated antioxidative capacity.

  17. Antioxidant responses and renal crystal formation in rainbow trout treated with melamine administered individually or in combination with cyanuric acid.

    Science.gov (United States)

    Pacini, Nicole; Prearo, Marino; Abete, Maria Cesarina; Brizio, Paola; Dörr, Ambrosius Josef Martin; Reimschuessel, Renate; Andersen, Wendy; Gasco, Laura; Righetti, Marzia; Elia, Antonia Concetta

    2013-01-01

    In 2007 and 2008, renal stone formation and kidney damage in human infants were linked to consumption of melamine (MEL)-contaminated infant formula, as well as renal failure and death in pets due to pet food containing both MEL and cyanuric acid (CYA). The aim of this study was to examine the effects of MEL and CYA administered individually or in combination on concentrations of certain metabolites and enzyme activities that serve as markers for oxidative stress in kidney and liver of rainbow trout. In addition, the levels of muscle MEL and renal crystal formation were determined. Trout were fed MEL and/or CYA for 8 wk at 250, 500, or 1000 mg of each compound/kg in feed. Fish muscle residues of MEL exhibited a dose-response relationship. Coexposure of trout to MEL and CYA at the highest dose led to lower MEL residue concentrations in muscle compared to exposure to MEL alone. Renal MEL-CYA complexes were found in kidneys of fish treated with combined MEL and CYA. A dose response was evident with respect to both (1) number of trout displaying renal crystals and (2) number of crystals per fish. Changes in concentration of antioxidant parameters, such as glutathione, superoxide dismutase, catalase, glutathione peroxidase, and glutathione S-transferase, were recorded in both tissues of MEL- and CYA-dosed trout. Lipid peroxidation was more pronounced in kidney than liver. Therefore, feed contaminated with both MEL and CYA could be problematic for fish, as MEL administered to trout, individually or in combination with CYA, may facilitate the onset of oxidative damage in trout. PMID:23721584

  18. Finite element model validation of bridge based on structural health monitoring—Part I: Response surface-based finite element model updating

    OpenAIRE

    Zhouhong Zong; Xiaosong Lin; Jie Niu

    2015-01-01

    In the engineering practice, merging statistical analysis into structural evaluation and assessment is a tendency in the future. As a combination of mathematical and statistical techniques, response surface (RS) methodology has been successfully applied to design optimization, response prediction and model validation. With the aid of RS methodology, these two serial papers present a finite element (FE) model updating and validation method for bridge structures based on structural health monit...

  19. Green tea polyphenol (−)-epigallocatechin-3-gallate triggered hepatotoxicity in mice: Responses of major antioxidant enzymes and the Nrf2 rescue pathway

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Dongxu; Wang, Yijun; Wan, Xiaochun [Key Laboratory of Tea Biochemistry & Biotechnology, School of Tea & Food Science, Anhui Agricultural University, Hefei, Anhui 230036 (China); Yang, Chung S. [Department of Chemical Biology, Ernest Mario School of Pharmacy, Rutgers, The State University of New Jersey, Piscataway, NJ 08854 (United States); Zhang, Jinsong, E-mail: zjs@ahau.edu.cn [Key Laboratory of Tea Biochemistry & Biotechnology, School of Tea & Food Science, Anhui Agricultural University, Hefei, Anhui 230036 (China)

    2015-02-15

    (−)-Epigallocatechin-3-gallate (EGCG), a constituent of green tea, has been suggested to have numerous health-promoting effects. On the other hand, high-dose EGCG is able to evoke hepatotoxicity. In the present study, we elucidated the responses of hepatic major antioxidant enzymes and nuclear factor erythroid 2-related factor 2 (Nrf2) rescue pathway to high-dose levels of EGCG in Kunming mice. At a non-lethal toxic dose (75 mg/kg, i.p.), repeated EGCG treatments markedly decreased the levels of superoxide dismutase, catalase, and glutathione peroxidase. As a rescue response, the nuclear distribution of Nrf2 was significantly increased; a battery of Nrf2-target genes, including heme oxygenase 1 (HO1), NAD(P)H:quinone oxidoreductase 1 (NQO1), glutathione S-transferase (GST), and those involved in glutathione and thioredoxin systems, were all up-regulated. At the maximum tolerated dose (45 mg/kg, i.p.), repeated EGCG treatments did not disturb the major antioxidant defense. Among the above-mentioned genes, only HO1, NQO1, and GST genes were significantly but modestly up-regulated, suggesting a comprehensive and extensive activation of Nrf2-target genes principally occurs at toxic levels of EGCG. At a lethal dose (200 mg/kg, i.p.), a single EGCG treatment dramatically decreased not only the major antioxidant defense but also the Nrf2-target genes, demonstrating that toxic levels of EGCG are able to cause a biphasic response of Nrf2. Overall, the mechanism of EGCG-triggered hepatotoxicity involves suppression of major antioxidant enzymes, and the Nrf2 rescue pathway plays a vital role for counteracting EGCG toxicity. - Highlights: • EGCG at maximum tolerated dose does not disturb hepatic major antioxidant defense. • EGCG at maximum tolerated dose modestly upregulates hepatic Nrf2 target genes. • EGCG at toxic dose suppresses hepatic major antioxidant enzymes. • EGCG at non-lethal toxic dose pronouncedly activates hepatic Nrf2 rescue response. • EGCG at

  20. Green tea polyphenol (−)-epigallocatechin-3-gallate triggered hepatotoxicity in mice: Responses of major antioxidant enzymes and the Nrf2 rescue pathway

    International Nuclear Information System (INIS)

    (−)-Epigallocatechin-3-gallate (EGCG), a constituent of green tea, has been suggested to have numerous health-promoting effects. On the other hand, high-dose EGCG is able to evoke hepatotoxicity. In the present study, we elucidated the responses of hepatic major antioxidant enzymes and nuclear factor erythroid 2-related factor 2 (Nrf2) rescue pathway to high-dose levels of EGCG in Kunming mice. At a non-lethal toxic dose (75 mg/kg, i.p.), repeated EGCG treatments markedly decreased the levels of superoxide dismutase, catalase, and glutathione peroxidase. As a rescue response, the nuclear distribution of Nrf2 was significantly increased; a battery of Nrf2-target genes, including heme oxygenase 1 (HO1), NAD(P)H:quinone oxidoreductase 1 (NQO1), glutathione S-transferase (GST), and those involved in glutathione and thioredoxin systems, were all up-regulated. At the maximum tolerated dose (45 mg/kg, i.p.), repeated EGCG treatments did not disturb the major antioxidant defense. Among the above-mentioned genes, only HO1, NQO1, and GST genes were significantly but modestly up-regulated, suggesting a comprehensive and extensive activation of Nrf2-target genes principally occurs at toxic levels of EGCG. At a lethal dose (200 mg/kg, i.p.), a single EGCG treatment dramatically decreased not only the major antioxidant defense but also the Nrf2-target genes, demonstrating that toxic levels of EGCG are able to cause a biphasic response of Nrf2. Overall, the mechanism of EGCG-triggered hepatotoxicity involves suppression of major antioxidant enzymes, and the Nrf2 rescue pathway plays a vital role for counteracting EGCG toxicity. - Highlights: • EGCG at maximum tolerated dose does not disturb hepatic major antioxidant defense. • EGCG at maximum tolerated dose modestly upregulates hepatic Nrf2 target genes. • EGCG at toxic dose suppresses hepatic major antioxidant enzymes. • EGCG at non-lethal toxic dose pronouncedly activates hepatic Nrf2 rescue response. • EGCG at

  1. Variation in biochemical and antioxidant attributes of Raphanus sativus in response to foliar application of plant leaf extracts as plant growth regulator

    Directory of Open Access Journals (Sweden)

    Rizwan Ashraf

    2016-06-01

    Full Text Available The present study was aimed to appraise the variations in biochemical, antioxidant and nutritional attributes of radish (Raphanus sativus L. under foliar application of plant leaf aqueous extracts i.e., mulberry leaf extract (MLE, brassica leaf extract (BLE, sorghum leaf extract (SLE and moringa leaf extract (MoLE as natural growth regulators. Samples were collected after three sprays of extracts and analyzed. Total phenolic constituents were determined using Folin–Ciocalteu reagent method, whereas antioxidant potential was evaluated by 1,1 diphenyl-2-picrylhydrazyl radical radical scavenging and reducing power assays. Results revealed that application of MLE, BLE, SLE, and MoLE not only improved growth, but also enhanced biochemical and antioxidant activities. Foliar spray of MoLE furnished relatively three folds higher amounts of extractable bioactive compounds (37.65 ± 0.94%, phenolic constituents (54.51–182.71 mg GAE/g f.w. The radical scavenging capacity (RSC and reducing potential were also enhanced considerably. Furthermore, the moisture, dietary fiber, crude protein, and carotenoids were also enhanced in response of foliar spray of plant extracts. From results, it is concluded that plant extracts are effective sources of natural growth regulars and might be useful for the production of vegetables with improved nutritional value and antioxidant activity.

  2. Growth, immune, antioxidant, and bone responses of heat stress-exposed broilers fed diets supplemented with tomato pomace

    Science.gov (United States)

    Hosseini-Vashan, S. J.; Golian, A.; Yaghobfar, A.

    2016-08-01

    A study was conducted to investigate the effects of supplementation of dried tomato pomace (DTP) on growth performance, relative weights of viscera, serum biological parameters, antioxidant status, immune response, and bone composition of broilers exposed to a high ambient temperature. A total of 352 one-day-old male broiler chickens were randomly divided into four groups consisting of four replicates with 22 birds each. One group was reared under the thermoneutral zone and fed a corn-soybean meal basal diet. The other three groups were subjected to a cyclic heat stress from 29 to 42 days of age (34 ± 1 °C, 55 % RH, 5 h/day). These birds were fed corn-soybean meal basal diet or the same diet supplemented with 3 % DTP (420 mg lycopene/kg diet) or 5 % (708 mg lycopene/kg diet) of DTP. Blood samples were collected on days 28 and 42, and the birds were slaughtered at the same times. Supplementation of 5 % of DTP increased body weight and production index and decreased feed conversion ratio during 1-28 days of age. On day 28, the broilers supplemented with 5 % DTP had lower serum triglycerides and higher high-density lipoprotein (HDL) cholesterol concentration than those on the other dietary treatments. The activities of glutathione peroxidase (GPx) and superoxide dismutase (SOD) were higher and the concentration of malondialdehyde (MDA) was lower in the broilers fed 5 % TP than those of the broilers fed other diets at 28 days of age. The effects of heat stress (HS) were impaired body weight, enhanced serum activities of alanine aminotransferase, aspartate aminotransferase, alkaline phosphatase, lipase, and MDA concentration while reducing the activities of GPx and SOD. Dried tomato pomace supplementation did not influence growth performance under HS but ameliorated the negative effects of HS on the serum enzyme activities, GPx activity, and lipid peroxidation. Heat stress did not change the relative weights of the lymphoid organs but reduced the total and IgG titers

  3. Growth, immune, antioxidant, and bone responses of heat stress-exposed broilers fed diets supplemented with tomato pomace

    Science.gov (United States)

    Hosseini-Vashan, S. J.; Golian, A.; Yaghobfar, A.

    2015-11-01

    A study was conducted to investigate the effects of supplementation of dried tomato pomace (DTP) on growth performance, relative weights of viscera, serum biological parameters, antioxidant status, immune response, and bone composition of broilers exposed to a high ambient temperature. A total of 352 one-day-old male broiler chickens were randomly divided into four groups consisting of four replicates with 22 birds each. One group was reared under the thermoneutral zone and fed a corn-soybean meal basal diet. The other three groups were subjected to a cyclic heat stress from 29 to 42 days of age (34 ± 1 °C, 55 % RH, 5 h/day). These birds were fed corn-soybean meal basal diet or the same diet supplemented with 3 % DTP (420 mg lycopene/kg diet) or 5 % (708 mg lycopene/kg diet) of DTP. Blood samples were collected on days 28 and 42, and the birds were slaughtered at the same times. Supplementation of 5 % of DTP increased body weight and production index and decreased feed conversion ratio during 1-28 days of age. On day 28, the broilers supplemented with 5 % DTP had lower serum triglycerides and higher high-density lipoprotein (HDL) cholesterol concentration than those on the other dietary treatments. The activities of glutathione peroxidase (GPx) and superoxide dismutase (SOD) were higher and the concentration of malondialdehyde (MDA) was lower in the broilers fed 5 % TP than those of the broilers fed other diets at 28 days of age. The effects of heat stress (HS) were impaired body weight, enhanced serum activities of alanine aminotransferase, aspartate aminotransferase, alkaline phosphatase, lipase, and MDA concentration while reducing the activities of GPx and SOD. Dried tomato pomace supplementation did not influence growth performance under HS but ameliorated the negative effects of HS on the serum enzyme activities, GPx activity, and lipid peroxidation. Heat stress did not change the relative weights of the lymphoid organs but reduced the total and IgG titers

  4. Rearing effect of biofloc on antioxidant and antimicrobial transcriptional response in Litopenaeus stylirostris shrimp facing an experimental sub-lethal hydrogen peroxide stress.

    Science.gov (United States)

    Cardona, Emilie; Saulnier, Denis; Lorgeoux, Bénédicte; Chim, Liet; Gueguen, Yannick

    2015-08-01

    This study compares the antioxidant and antimicrobial transcriptional expression of blue shrimps reared according to two different systems, BioFloc Technology (BFT) and Clear sea Water (CW) and their differential responses when facing an experimental sublethal hydrogen peroxide stress. After 30 days of rearing, juvenile shrimps were exposed to H2O2 stress at a concentration of 30 ppm during 6 h. The oxidative stress caused by H2O2 was examined in the digestive glands of the shrimp, in which antioxidant enzyme (AOE) and antimicrobial peptide (AMP) gene expression were analysed by quantitative real-time PCR. Results showed that rearing conditions did not affect the expression of genes encoding AOEs or AMPs. However, H2O2 stress induced a differential response in expression between shrimps from the two rearing treatments (BFT and CW). Comparative analysis of the expression profiles indicates that catalase transcripts were significantly upregulated by H2O2 stress for BFT shrimps while no change was observed for CW shrimps. In contrast, H2O2 caused down-regulation of superoxide dismutase and glutathione transferase transcripts and of the three AMP transcripts studied (penaeidin 2 and 3, and crustin) for CW shrimps, while no effect was observed on BFT shrimp transcript levels. These results suggested that BFT shrimps maintained antioxidant and AMP responses after stress and therefore can effectively protect their cells against oxidative stress, while CW shrimp immune competence seems to decrease after stress. PMID:26052010

  5. Activity of antioxidant enzymes and physiological responses in ark shell, Scapharca broughtonii, exposed to thermal and osmotic stress: effects on hemolymph and biochemical parameters.

    Science.gov (United States)

    An, Myung In; Choi, Cheol Young

    2010-01-01

    Changes in water temperature and salinity are responsible for a variety of physiological stress responses in aquatic organisms. Stress induced by these factors was recently associated with enhanced reactive oxygen species (ROS) generation, which caused oxidative damage. In the present study, we investigated the time-related effects of changes in water temperature and salinity on mRNA expression and the activities of antioxidant enzymes (SOD and CAT) and lipid peroxidation (LPO) in the gills and digestive glands of the ark shell, Scapharca broughtonii. To investigate physiological responses, hydrogen peroxide (H(2)O(2)), lysozyme activity, aspartate aminotransferase (AspAT), and alanine aminotransferase (AlaAT) were measured in the hemolymph. Water temperature and salinity changes significantly increased antioxidant enzyme mRNA expression and activity in the digestive glands and gills in a time-dependent manner. H(2)O(2) concentrations increased significantly in the high-temperature and hyposalinity treatments. LPO, AspAT and AlaAT levels also increased significantly in a time-dependent manner, while lysozyme activity decreased. These results suggest that antioxidant enzymes play important roles in reducing oxidative stress in ark shells exposed to changes in water temperature and salinity.

  6. Dietary glutamine supplementation effects on amino acid metabolism, intestinal nutrient absorption capacity and antioxidant response of gilthead sea bream (Sparus aurata) juveniles.

    Science.gov (United States)

    Coutinho, F; Castro, C; Rufino-Palomares, E; Ordóñez-Grande, B; Gallardo, M A; Oliva-Teles, A; Peres, H

    2016-01-01

    A study was undertaken to evaluate dietary glutamine supplementation effects on gilthead sea bream performance, intestinal nutrient absorption capacity, hepatic and intestinal glutamine metabolism and oxidative status. For that purpose gilthead sea bream juveniles (mean weight 13.0g) were fed four isolipidic (18% lipid) and isonitrogenous (43% protein) diets supplemented with 0, 0.5, 1 and 2% glutamine for 6weeks. Fish performance, body composition and intestinal nutrient absorption capacity were not affected by dietary glutamine levels. Hepatic and intestinal glutaminase (GlNase), glutamine synthetase (GSase), alanine aminotransferase, aspartate aminotransferase and glutamate dehydrogenase activities were also unaffected by dietary glutamine supplementation. In the intestine GlNase activity was higher and GSase/GlNase ratio was two-fold lower than in the liver, suggesting a higher use of glutamine for energy production by the intestine than by the liver. The liver showed higher catalase and glucose-6-phosphate dehydrogenase activities, while the intestine presented higher glutathione peroxidase and glutathione reductase activities and oxidised glutathione content, which seems to reveal a higher glutathione dependency of the intestinal antioxidant response. Total and reduced glutathione contents in liver and intestine and superoxide dismutase activity in the intestine were enhanced by dietary glutamine, though lipid peroxidation values were not affected. Overall, differences between liver and intestine glutamine metabolism and antioxidant response were identified and the potential of dietary glutamine supplementation to gilthead sea bream's antioxidant response was elucidated.

  7. Deployment of response surface methodology to optimize recovery of dark fresh fig (Ficus carica L., var. Azenjar) total phenolic compounds and antioxidant activity.

    Science.gov (United States)

    Bachir Bey, Mostapha; Meziant, Leila; Benchikh, Yassine; Louaileche, Hayette

    2014-11-01

    Optimum conditions for extracting total phenolic compounds (TPC) and antioxidant activity from fresh dark fig (Ficus carica L.) have been investigated using response surface methodology (RSM). The Box-Behnken design was used to investigate the effects of three independent variables, acetone concentration (40-80%), temperature (25-65 °C), and time (60-120 min), on the response. Regression analysis showed that about 96% of the variation was explained by the models. P-value for the lack of fit was insignificant which confirmed the validity of models. Response surface analysis showed that the optimal extraction parameters that maximized antioxidants extraction were 63.48% acetone, 115.14 min, and 48.66 °C. Under optimum conditions the corresponding experimental values for TPC and antioxidant activity were 536.43 and 71.86 mg GAE/100 g DM. The experimental values are in accordance with those predicted, indicating the suitability of the model and the success of RSM in optimizing the extraction conditions.

  8. A role for neuronal cAMP responsive-element binding (CREB)-1 in brain responses to calorie restriction.

    Science.gov (United States)

    Fusco, Salvatore; Ripoli, Cristian; Podda, Maria Vittoria; Ranieri, Sofia Chiatamone; Leone, Lucia; Toietta, Gabriele; McBurney, Michael W; Schütz, Günther; Riccio, Antonella; Grassi, Claudio; Galeotti, Tommaso; Pani, Giovambattista

    2012-01-10

    Calorie restriction delays brain senescence and prevents neurodegeneration, but critical regulators of these beneficial responses other than the NAD(+)-dependent histone deacetylase Sirtuin-1 (Sirt-1) are unknown. We report that effects of calorie restriction on neuronal plasticity, memory and social behavior are abolished in mice lacking cAMP responsive-element binding (CREB)-1 in the forebrain. Moreover, CREB deficiency drastically reduces the expression of Sirt-1 and the induction of genes relevant to neuronal metabolism and survival in the cortex and hippocampus of dietary-restricted animals. Biochemical studies reveal a complex interplay between CREB and Sirt-1: CREB directly regulates the transcription of the sirtuin in neuronal cells by binding to Sirt-1 chromatin; Sirt-1, in turn, is recruited by CREB to DNA and promotes CREB-dependent expression of target gene peroxisome proliferator-activated receptor-γ coactivator-1α and neuronal NO Synthase. Accordingly, expression of these CREB targets is markedly reduced in the brain of Sirt KO mice that are, like CREB-deficient mice, poorly responsive to calorie restriction. Thus, the above circuitry, modulated by nutrient availability, links energy metabolism with neurotrophin signaling, participates in brain adaptation to nutrient restriction, and is potentially relevant to accelerated brain aging by overnutrition and diabetes. PMID:22190495

  9. OPTIMIZATION OF EXTRACTION OF PHENOLIC ANTIOXIDANTS FROM TEA (CAMELLIA SINENSIS L.) FRUIT PEEL BIOMASS USING RESPONSE SURFACE METHODOLOGY

    OpenAIRE

    Ping Xu; Jinsong Bao; Junjie Gao; Tao Zhou; Yuefei Wang

    2012-01-01

    Tea (Camellia sinensis L.) fruit peel, the main byproduct during the manufacture of tea seed oil, was used as raw material for the recovery of phenolic antioxidants. The effect of ethanol concentration, extraction time, and extraction temperature on total phenolic content (TPC) and ferric-reducing antioxidant power (FRAP) of the extracts from tea fruit peel was investigated. The maximum predicted TPC (47.5 mg GAE/g dry peel) was obtained under the optimum recovery conditions (43% ethanol, 60°...

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

    OpenAIRE

    Fansheng Kong; Shujuan Yu; Zeng Feng; Xinlan Wu

    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 (20...

  11. Antioxidant Responses of Vallisneria asiatica to Eutrophic Sediments in Lake Taihu, China.

    Science.gov (United States)

    Kang, Caixia; Kuba, Takahiro; Hao, Aimin; Iseri, Yasushi

    2015-08-01

    Three kinds of representative sediments were obtained from a macrophyte-dominated bay (East Lake Taihu) and two algae-dominated regions (Western Lake Taihu and Meiliang Bay). Physiological responses of Vallisneria asiatica to these sediments were compared. Results from 20 days exposures showed no obvious differences in malondialdehyde (MDA) in roots, while the MDA content in leaves of plants exposed to Western Lake Taihu sediment was significantly (p<0.05) higher than those exposed to the other two sediments. In comparison to the other two sediments, plants exposed to Western Lake Taihu sediment showed significantly lower (p<0.05) superoxide dismutase in roots and leaves on the 10th and 40th day. On the 40th day, root catalase (CAT) activities in V. asiatica from Western Lake Taihu and Meiliang Bay sediments were lower than that from East Lake Taihu sediment, while leaf CAT activity in V. asiatica from Western Lake Taihu sediment was higher than that from East Lake Taihu sediment (p<0.05). Western Lake Taihu sediment caused more serious oxidative stress in V. asiatica than East Lake Taihu sediment. Results indicated eutrophic sediment was a contributing factor in the disappearance of V. asiatica in Western Lake Taihu. PMID:26070371

  12. Taste signaling elements expressed in gut enteroendocrine cells regulate nutrient-responsive secretion of gut hormones.

    Science.gov (United States)

    Kokrashvili, Zaza; Mosinger, Bedrich; Margolskee, Robert F

    2009-09-01

    Many of the receptors and downstream signaling elements involved in taste detection and transduction are also expressed in enteroendocrine cells where they underlie the chemosensory functions of the gut. In one well-known example of gastrointestinal chemosensation (the "incretin effect"), it is known that glucose that is given orally, but not systemically, induces secretion of glucagon-like peptide 1 and glucose-dependent insulinotropic peptide (the incretin hormones), which in turn regulate appetite, insulin secretion, and gut motility. Duodenal L cells express sweet taste receptors, the taste G protein gustducin, and several other taste transduction elements. Knockout mice that lack gustducin or the sweet taste receptor subunit T1r3 have deficiencies in secretion of glucagon-like peptide 1 and glucose-dependent insulinotropic peptide and in the regulation of plasma concentrations of insulin and glucose in response to orally ingested carbohydrate-ie, their incretin effect is dysfunctional. Isolated small intestine and intestinal villi from gustducin null mice displayed markedly defective glucagon-like peptide 1 secretion in response to glucose, indicating that this is a local circuit of sugar detection by intestinal cells followed by hormone secretion from these same cells. Modulating hormone secretion from gut "taste cells" may provide novel treatments for obesity, diabetes, and malabsorption syndromes. PMID:19571229

  13. A CYCLIC-AMP RESPONSE ELEMENT IS INVOLVED IN RETINOIC ACID-DEPENDENT RAR-BETA-2 PROMOTER ACTIVATION

    NARCIS (Netherlands)

    KRUYT, FAE; FOLKERS, G; VANDENBRINK, CE; VANDERSAAG, PT; Kruyt, Frank

    1992-01-01

    Activation of the retinoic acid receptor (RAR) beta2 promoter is known to be mediated by a RA response element located in the proximity of the TATA-box. By deletion studies in P19 embryonal carcinoma cells we have analyzed the RARbeta2 promoter for the presence of additional regulatory elements. We

  14. Characterization of a retinoic acid responsive element isolated by whole genome PCR.

    Science.gov (United States)

    Costa-Giomi, M P; Gaub, M P; Chambon, P; Abarzúa, P

    1992-01-01

    We have used whole PCR in an attempt to isolate novel retinoic acid (RA) responsive genes. We cloned several small genomic fragments from total human DNA containing putative retinoic acid responsive elements (RAREs) selected by direct binding to the retinoic acid receptor alpha (RAR alpha). We report here that an oligonucleotide containing a sequence from one of the cloned human DNA fragments, and referred to as alpha 1, functions as an authentic RARE. It is shown that both RAR alpha and RAR beta produced in Cos cells as well as in vitro translated RAR alpha bind directly and sequence-specifically to the alpha 1RARE. By mutational analysis it is demonstrated that the alpha 1RARE consists of an imperfect direct repeat of the estrogen- and thyroid hormone-related AGGTCA half-site motif separated by a 5 bp spacer. The orientation and spacing of the half-site repeats are shown to play a critical role in RAR recognition. When cloned upstream of a TK-Luc reporter, the alpha 1RARE is shown to confer responsiveness to RA in an orientation-independent fashion in F9 and CV-1 cells. The magnitude of the RA response mediated by the alpha 1RARE differed in these cell lines. Images PMID:1320257

  15. Spinosad Induces Antioxidative Response and Ultrastructure Changes in Males of Red Palm Weevil Rhynchophorus ferrugineus (Coleoptera: Dryophthoridae)

    Science.gov (United States)

    Abdelsalam, Salaheldin A.; Alzahrani, Abdullah M.; Elmenshawy, Omar M.; Abdel-Moneim, Ashraf M.

    2016-01-01

    The red palm weevil, Rhynchophorus ferrugineus, is of great concern worldwide, especially in the Middle East, where dates are a strategic crop. Despite their ecological hazard, insecticides remain the most effective means of control. A bioinsecticide of bacterial origin, spinosad is effective against several pests, and its efficacy against male R. ferrugineus was assessed in the present study. The antioxidative responses of key enzymes including catalase (CAT), superoxide dismutase (SOD), and glutathione-S-transferase (GST) to spinosad were investigated in the midgut and testes, and the effects of this insecticide on the cell ultrastructure of the midgut, Malpighian tubules, and testes were also determined. The lethal concentration 50 of spinosad was measured at 58.8 ppm, and the insecticide inhibited the activities of CAT, SOD, and GST in the midgut. However, no significant changes in the activities of these enzymes were observed in the testes. Spinosad treatment resulted in concentration-dependent changes in the cellular organelles of the midgut, Malpighian tubules, and testes of R. ferrugineus, and some of these effects were similar to those exerted by other xenobiotics. However, specific changes were observed as a result of spinosad treatment, including an increase in the number and size of concretions in Malpighian tubule cells and the occasional absence of the central pair of microtubules in the axonemes of sperm tails. This study introduces spinosad for potential use as an insecticide within an integrated control program against male red palm weevils. Additionally, the study provides biochemical and ultrastructural evidence for use in the development of bioindicators.

  16. A Multi-Element Approach to Location Inference of Twitter: A Case for Emergency Response

    Directory of Open Access Journals (Sweden)

    Farhad Laylavi

    2016-04-01

    Full Text Available Since its inception, Twitter has played a major role in real-world events—especially in the aftermath of disasters and catastrophic incidents, and has been increasingly becoming the first point of contact for users wishing to provide or seek information about such situations. The use of Twitter in emergency response and disaster management opens up avenues of research concerning different aspects of Twitter data quality, usefulness and credibility. A real challenge that has attracted substantial attention in the Twitter research community exists in the location inference of twitter data. Considering that less than 2% of tweets are geotagged, finding location inference methods that can go beyond the geotagging capability is undoubtedly the priority research area. This is especially true in terms of emergency response, where spatial aspects of information play an important role. This paper introduces a multi-elemental location inference method that puts the geotagging aside and tries to predict the location of tweets by exploiting the other inherently attached data elements. In this regard, textual content, users’ profile location and place labelling, as the main location-related elements, are taken into account. Location-name classes in three granularity levels are defined and employed to look up the location references from the location-associated elements. The inferred location of the finest granular level is assigned to a tweet, based on a novel location assignment rule. The location assigned by the location inference process is considered to be the inferred location of a tweet, and is compared with the geotagged coordinates as the ground truth of the study. The results show that this method is able to successfully infer the location of 87% of the tweets at the average distance error of 12.2 km and the median distance error of 4.5 km, which is a significant improvement compared with that of the current methods that can predict the location

  17. A new cAMP response element in the transcribed region of the human c-fos gene.

    OpenAIRE

    Härtig, E; Loncarević, I F; Büscher, M.; Herrlich, P; Rahmsdorf, H J

    1991-01-01

    In NIH 3T3 cells the c-fos gene is induced rapidly and transiently by cAMP. As shown by the analysis of 3T3 cells stably transfected with promoter mutants of the human c-fos gene this induction does not depend on the dyad symmetry element (position -320 to -300), but involves at least two other non-related sites: an element located around position -60 resembling the cAMP response element of the fibronectin and somatostatin genes (which has been described before), and an element located betwee...

  18. Extraction of antioxidants from borage (Borago officinalis L.) leaves—Optimization by response surface method and application in oil-in-water emulsions

    OpenAIRE

    Francisco Segovia; Bryshila Lupo; Sara Peiró; Gordon, Michael H.; María Pilar Almajano

    2014-01-01

    Borage (Borago officinalis L.) is a typical Spanish plant. During processing, 60% are leaves. The aim of this work is to model and optimize the extraction of polyphenol from borage leaves using the response surface method (RSM) and to use this extract for application in emulsions. The responses were: total polyphenol content (TPC), antioxidant capacity by ORAC, and rosmarinic acid by HPLC. The ranges of the variables temperature, ethanol content and time were 50–90 °C, 0%–30%–60% ethanol (v/v...

  19. A Space-Time Finite Element Model for Design and Control Optimization of Nonlinear Dynamic Response

    Directory of Open Access Journals (Sweden)

    P.P. Moita

    2008-01-01

    Full Text Available A design and control sensitivity analysis and multicriteria optimization formulation is derived for flexible mechanical systems. This formulation is implemented in an optimum design code and it is applied to the nonlinear dynamic response. By extending the spatial domain to the space-time domain and treating the design variables as control variables that do not change with time, the design space is included in the control space. Thus, one can unify in one single formulation the problems of optimum design and optimal control. Structural dimensions as well as lumped damping and stiffness parameters plus control driven forces, are considered as decision variables. The dynamic response and its sensitivity with respect to the design and control variables are discretized via space-time finite elements, and are integrated at-once, as it is traditionally used for static response. The adjoint system approach is used to determine the design sensitivities. Design optimization numerical examples are performed. Nonlinear programming and optimality criteria may be used for the optimization process. A normalized weighted bound formulation is used to handle multicriteria problems.

  20. Comparison of gamma- and beta radiation stress responses on anti-oxidative defense system and DNA modifications in Lemna minor

    Energy Technology Data Exchange (ETDEWEB)

    Van Hoeck, Arne [SCK.CEN, Boeretang 200 2400 Mol (Belgium); University of Antwerp, Groenenborgerlaan 171, 2020 Antwerpen (Belgium); Horemans, Nele; Van Hees, May; Nauts, Robin; Vandenhove, Hildegarde [SCK.CEN, Boeretang 200 2400 Mol (Belgium); Knapen, Dries; Blust, Ronny [University of Antwerp, Groenenborgerlaan 171, 2020 Antwerpen (Belgium)

    2014-07-01

    frond have been implemented in a dosimetric model derived from ERICA tool. This enabled a reliable comparison of dose-dependent endpoints between gamma- and beta radiation. Dose rates varied from 15 and 1500 mGy/hr, and 19 from 19000 μGy/hr for gamma- and beta radiation respectively. The classic growth related endpoints, like biomass and frond area, were measured and compared with biochemical and molecular endpoints. Therefore, DNA modifications were analyzed to evaluate biological DNA damage and ROS accumulation in plants together with activities of anti-oxidative enzymes to evaluate oxidative stress response. A dose-response curve with 60 percent growth inhibition was determined for gamma radiation and morphological growth effects in root system were observed for beta radiation. Preliminary results showed similar responses in peroxidase activities between both radiation types. These results and ongoing investigations will help to unravel the differences and similarities in response mechanisms for various radiation types in plant systems. As multiple levels in biological organisation of the organism were considered, and also different dose rates taken into account, this approach allows a better understanding the toxic mode of action of radiation stress in higher plants. This research was supported by the European Commission Contract Fission-2010-3.5.1-269672 to Strategy for Allied Radioecology (www.star-radioecology.org) and a project of the Fund for Scientific Research (FWO-Vlaanderen, G.A040.11N) (authors)

  1. Finite element analysis of structural response of superconducting magnet for a fusion reactor

    International Nuclear Information System (INIS)

    In the proposal Tokamak fusion reactor, the superconducting unit consists of an assembly of D-shaped magnets standing vertically and arranged in a toroidal configuration. Each magnet is a composite structure comprised of Nb-22%Ti and Nb-48%Ti, and stabilizing metals such as copper and aluminum or stainless steel held together by reinforced epoxies which also serve as insulators and spacers. The magnets are quite large, typically 15-20 meters in diameter with rectangular cross sections around 0.93x2m. Under static loading condition, the magnet is subjected to dead weight and large magnetic field forces, which may induce high stresses in the structure. Furthermore, additional stresses due to earthquake must also be considered for the design of the component. Both static and dynamic analyses of a typical field magnet have been performed by use of the finite element method. The magnet was assumed to be linearly elastic with equivalent homogeneous material properties. Various finite element models have been considered in order to better represent the structure for a particular loading case. For earthquake analysis, the magnet was assumed to be subjected to 50% of the El Centro 1940 earthquake and the dynamic response was obtained by the displacement spectrum analysis procedure. In the paper, numerical results are presented and the structure behavior of the magnet under static and dynamic loading conditions is discussed

  2. Identification and Validation of a Putative Polycomb Responsive Element in the Human Genome.

    Directory of Open Access Journals (Sweden)

    Hemant Bengani

    Full Text Available Epigenetic cellular memory mechanisms that involve polycomb and trithorax group of proteins are well conserved across metazoans. The cis-acting elements interacting with these proteins, however, are poorly understood in mammals. In a directed search we identified a potential polycomb responsive element with 25 repeats of YY1 binding motifthatwe designate PRE-PIK3C2B as it occurs in the first intron of human PIK3C2B gene. It down regulates reporter gene expression in HEK cells and the repression is dependent on polycomb group of proteins (PcG. We demonstrate that PRE-PIK3C2B interacts directly with YY1 in vitro and recruits PRC2 complex in vivo. The localization of PcG proteins including YY1 to PRE-PIK3C2B in HEK cells is decreased on knock-down of either YY1 or SUZ12. Endogenous PRE-PIK3C2B shows bivalent marking having H3K27me3 and H3K4me3 for repressed and active state respectively. In transgenic Drosophila, PRE-PIK3C2B down regulates mini-white expression, exhibits variegation and pairing sensitive silencing (PSS, which has not been previously demonstrated for mammalian PRE. Taken together, our results strongly suggest that PRE-PIK3C2B functions as a site of interaction for polycomb proteins.

  3. Formation of a Polycomb-Domain in the Absence of Strong Polycomb Response Elements.

    Science.gov (United States)

    De, Sandip; Mitra, Apratim; Cheng, Yuzhong; Pfeifer, Karl; Kassis, Judith A

    2016-07-01

    Polycomb group response elements (PREs) in Drosophila are DNA-elements that recruit Polycomb proteins (PcG) to chromatin and regulate gene expression. PREs are easily recognizable in the Drosophila genome as strong peaks of PcG-protein binding over discrete DNA fragments; many small but statistically significant PcG peaks are also observed in PcG domains. Surprisingly, in vivo deletion of the four characterized strong PREs from the PcG regulated invected-engrailed (inv-en) gene complex did not disrupt the formation of the H3K27me3 domain and did not affect inv-en expression in embryos or larvae suggesting the presence of redundant PcG recruitment mechanism. Further, the 3D-structure of the inv-en domain was only minimally altered by the deletion of the strong PREs. A reporter construct containing a 7.5kb en fragment that contains three weak peaks but no large PcG peaks forms an H3K27me3 domain and is PcG-regulated. Our data suggests a model for the recruitment of PcG-complexes to Drosophila genes via interactions with multiple, weak PREs spread throughout an H3K27me3 domain. PMID:27466807

  4. Application of finite element, global polynomial, and kriging response surfaces in Progressive Lattice Sampling designs

    Energy Technology Data Exchange (ETDEWEB)

    ROMERO,VICENTE J.; SWILER,LAURA PAINTON; GIUNTA,ANTHONY A.

    2000-04-25

    This paper examines the modeling accuracy of finite element interpolation, kriging, and polynomial regression used in conjunction with the Progressive Lattice Sampling (PLS) incremental design-of-experiments approach. PLS is a paradigm for sampling a deterministic hypercubic parameter space by placing and incrementally adding samples in a manner intended to maximally reduce lack of knowledge in the parameter space. When combined with suitable interpolation methods, PLS is a formulation for progressive construction of response surface approximations (RSA) in which the RSA are efficiently upgradable, and upon upgrading, offer convergence information essential in estimating error introduced by the use of RSA in the problem. The three interpolation methods tried here are examined for performance in replicating an analytic test function as measured by several different indicators. The process described here provides a framework for future studies using other interpolation schemes, test functions, and measures of approximation quality.

  5. A novel human polycomb binding site acts as a functional polycomb response element in Drosophila.

    Directory of Open Access Journals (Sweden)

    Suresh Cuddapah

    Full Text Available Polycomb group (PcG proteins are key chromatin regulators implicated in multiple processes including embryonic development, tissue homeostasis, genomic imprinting, X-chromosome inactivation, and germ cell differentiation. The PcG proteins recognize target genomic loci through cis DNA sequences known as Polycomb Response Elements (PREs, which are well characterized in Drosophila. However, mammalian PREs have been elusive until two groups reported putative mammalian PREs recently. Consistent with the existence of mammalian PREs, here we report the identification and characterization of a potential PRE from human T cells. The putative human PRE has enriched binding of PcG proteins, and such binding is dependent on a key PcG component SUZ12. We demonstrate that the putative human PRE carries both genetic and molecular features of Drosophila PRE in transgenic flies, implying that not only the trans PcG proteins but also certain features of the cis PREs are conserved between mammals and Drosophila.

  6. Thyroid hormone response element half-site organization and its effect on thyroid hormone mediated transcription.

    Directory of Open Access Journals (Sweden)

    Martin A Paquette

    Full Text Available Thyroid hormone (TH exerts its effects by binding to the thyroid hormone receptor (TR, which binds to TH response elements (TREs to regulate target gene expression. We investigated the relative ability of liganded homodimers TR and retinoid X receptor (RXR, and the heterodimer TR/RXR, to regulate gene expression for the TRE half-site organizations: direct repeat 4 (DR4, inverted repeat 0 (IR0 and everted repeat 6 (ER6. Luciferase reporter assays using a DR4 TRE suggest that both the TR homodimer and TR/RXR heterodimer regulate luciferase expression in the presence of their respective ligands. However, in the presence of the IR0 TRE, transfection with TR/RXR and RXR alone increased luciferase activity and there was no effect of TR alone. The presence of 9-cis-retinoic acid was necessary for luciferase expression, whereas TH treatment alone was insufficient. For the ER6 TRE, transfection with TR/RXR, TR alone and RXR alone (in the presence of their respective ligands all caused a significant increase in luciferase activity. When both ligands were present, transfection with both TR/RXR caused more activation. Finally, we investigated the efficacy of the TR-antagonist 1-850 in inhibiting transcription by TR or TR/RXR at DR4 and ER6 TREs. We found that 1-850 did not suppress luciferase activation in the presence of TR/RXR for the ER6 TRE, suggesting conformational changes of the ligand binding domain of the TR when bound to different TRE half-site organizations. Collectively, the findings indicate that there are fundamental differences between TRE configurations that affect nuclear receptor interactions with the response element and ability to bind ligands and antagonists.

  7. Thyroid Hormone Response Element Half-Site Organization and Its Effect on Thyroid Hormone Mediated Transcription

    Science.gov (United States)

    Paquette, Martin A.; Atlas, Ella; Wade, Mike G.; Yauk, Carole L.

    2014-01-01

    Thyroid hormone (TH) exerts its effects by binding to the thyroid hormone receptor (TR), which binds to TH response elements (TREs) to regulate target gene expression. We investigated the relative ability of liganded homodimers TR and retinoid X receptor (RXR), and the heterodimer TR/RXR, to regulate gene expression for the TRE half-site organizations: direct repeat 4 (DR4), inverted repeat 0 (IR0) and everted repeat 6 (ER6). Luciferase reporter assays using a DR4 TRE suggest that both the TR homodimer and TR/RXR heterodimer regulate luciferase expression in the presence of their respective ligands. However, in the presence of the IR0 TRE, transfection with TR/RXR and RXR alone increased luciferase activity and there was no effect of TR alone. The presence of 9-cis-retinoic acid was necessary for luciferase expression, whereas TH treatment alone was insufficient. For the ER6 TRE, transfection with TR/RXR, TR alone and RXR alone (in the presence of their respective ligands) all caused a significant increase in luciferase activity. When both ligands were present, transfection with both TR/RXR caused more activation. Finally, we investigated the efficacy of the TR-antagonist 1–850 in inhibiting transcription by TR or TR/RXR at DR4 and ER6 TREs. We found that 1–850 did not suppress luciferase activation in the presence of TR/RXR for the ER6 TRE, suggesting conformational changes of the ligand binding domain of the TR when bound to different TRE half-site organizations. Collectively, the findings indicate that there are fundamental differences between TRE configurations that affect nuclear receptor interactions with the response element and ability to bind ligands and antagonists. PMID:24971931

  8. Glutathione Reductase/Glutathione Is Responsible for Cytotoxic Elemental Sulfur Tolerance via Polysulfide Shuttle in Fungi*

    OpenAIRE

    Sato, Ikuo; Shimatani, Kanami; Fujita, Kensaku; Abe, Tsuyoshi; Shimizu, Motoyuki; Fujii, Tatsuya; Hoshino, Takayuki; Takaya, Naoki

    2011-01-01

    Fungi that can reduce elemental sulfur to sulfide are widely distributed, but the mechanism and physiological significance of the reaction have been poorly characterized. Here, we purified elemental sulfur-reductase (SR) and cloned its gene from the elemental sulfur-reducing fungus Fusarium oxysporum. We found that NADPH-glutathione reductase (GR) reduces elemental sulfur via glutathione as an intermediate. A loss-of-function mutant of the SR/GR gene generated less sulfide from elemental sulf...

  9. The FPIN2 code - an application of the finite element method to the analysis of the transient response of oxide and metal fuel elements

    International Nuclear Information System (INIS)

    The FPIN2 code simulates the thermal-mechanical response of fast reactor fuel pins to transient events. Temperatures of the fuel pin and coolant are calculated using a simple pin-in-a-pipe geometry. The mechanical analysis uses an implicit finite element formulation with linear shape functions which allow for general material behavior in the fuel and cladding including cracking and melting. This formulation provides a very convenient structure for implementing different models and improvements in algorithms. The paper summarizes the FPIN2 methodology and presents results for the transient response of both oxide and metallic fuel pins under similar overpower transients. (author)

  10. Production, characterization, and selection of the heating elements for the response stabilization of the CUORE bolometers

    International Nuclear Information System (INIS)

    One of the critical issues while operating bolometric detectors over periods of time of 1 year or more consists of keeping their response stable within a 0.1% level, despite the unavoidable temperature fluctuations of the cryogenic set-up. By using an energy pulser, which periodically delivers a fixed amount of energy in the absorber, it is possible to stabilize the response of the bolometers. A stabilization technique using heating devices, made up of heavily doped semiconductor material (well above the metal-to-insulator transition), has been developed in the framework of the CUORE experiment. In this paper we describe in detail the procedure for the realization of the heating elements, based on silicon planar technology. We then report on the multi-step low temperature characterization (77 K, 4.2 K, 1.5 K, 35 mK) of the heaters. Finally, an example of achieved stabilization for a CUORE-like detector is reported. The ∼1500 heaters tested at ∼1.5K show less than 0.5% change in resistance between 30μV and 3 mV, and less than 1% change in value between 50 mK and 800 mK. In particular, the resistance change between 4.2 K and 1.5 K is less than 0.1%.

  11. ZAP-70 and p72syk are signaling response elements through MHC class II molecules

    DEFF Research Database (Denmark)

    Kanner, S B; Grosmaire, L S; Blake, J;

    1995-01-01

    -activated human T-cells. In both tonsillar B-lymphocytes and B-cell leukemia lines, p72syk was rapidly phosphorylated on tyrosine residues following HLA-DR cross-linking. Tyrosine phosphorylation of p72syk induced through ligation of either the B-cell antigen receptor or class II molecules was potently inhibited...... intracellular calcium. Similar responses have been observed in B-cells following stimulation of MHC class II molecules, including the increased production of intracellular cAMP. In this report, we demonstrate that the ZAP-70 tyrosine kinase is a responsive signaling element following cross-linking of HLA-DR in...... antibody induced receptor ligation, bacterial superantigen (SEA and SEB) treatment of HLA-DR+ T-cells stimulated ZAP-70 tyrosine phosphorylation, consistent with class II transmembrane signaling by ligation of HLA-DR and V beta in cis. Modulation of the TCR/CD3 led to abrogation of class II induced ZAP-70...

  12. Involvement of the sieve element cytoskeleton in electrical responses to cold shocks.

    Science.gov (United States)

    Hafke, Jens B; Ehlers, Katrin; Föller, Jens; Höll, Sabina-Roxana; Becker, Stefanie; van Bel, Aart J E

    2013-06-01

    This study dealt with the visualization of the sieve element (SE) cytoskeleton and its involvement in electrical responses to local cold shocks, exemplifying the role of the cytoskeleton in Ca(2+)-triggered signal cascades in SEs. High-affinity fluorescent phalloidin as well as immunocytochemistry using anti-actin antibodies demonstrated a fully developed parietal actin meshwork in SEs. The involvement of the cytoskeleton in electrical responses and forisome conformation changes as indicators of Ca(2+) influx was investigated by the application of cold shocks in the presence of diverse actin disruptors (latrunculin A and cytochalasin D). Under control conditions, cold shocks elicited a graded initial voltage transient, ΔV1, reduced by external La(3+) in keeping with the involvement of Ca(2+) channels, and a second voltage transient, ΔV2. Cytochalasin D had no effect on ΔV1, while ΔV1 was significantly reduced with 500 nm latrunculin A. Forisome dispersion was triggered by cold shocks of 4°C or greater, which was indicative of an all-or-none behavior. Forisome dispersion was suppressed by incubation with latrunculin A. In conclusion, the cytoskeleton controls cold shock-induced Ca(2+) influx into SEs, leading to forisome dispersion and sieve plate occlusion in fava bean (Vicia faba). PMID:23624858

  13. Involvement of the Sieve Element Cytoskeleton in Electrical Responses to Cold Shocks1[W

    Science.gov (United States)

    Hafke, Jens B.; Ehlers, Katrin; Föller, Jens; Höll, Sabina-Roxana; Becker, Stefanie; van Bel, Aart J.E.

    2013-01-01

    This study dealt with the visualization of the sieve element (SE) cytoskeleton and its involvement in electrical responses to local cold shocks, exemplifying the role of the cytoskeleton in Ca2+-triggered signal cascades in SEs. High-affinity fluorescent phalloidin as well as immunocytochemistry using anti-actin antibodies demonstrated a fully developed parietal actin meshwork in SEs. The involvement of the cytoskeleton in electrical responses and forisome conformation changes as indicators of Ca2+ influx was investigated by the application of cold shocks in the presence of diverse actin disruptors (latrunculin A and cytochalasin D). Under control conditions, cold shocks elicited a graded initial voltage transient, ΔV1, reduced by external La3+ in keeping with the involvement of Ca2+ channels, and a second voltage transient, ΔV2. Cytochalasin D had no effect on ΔV1, while ΔV1 was significantly reduced with 500 nm latrunculin A. Forisome dispersion was triggered by cold shocks of 4°C or greater, which was indicative of an all-or-none behavior. Forisome dispersion was suppressed by incubation with latrunculin A. In conclusion, the cytoskeleton controls cold shock-induced Ca2+ influx into SEs, leading to forisome dispersion and sieve plate occlusion in fava bean (Vicia faba). PMID:23624858

  14. Seismic response of continuous span bridges through fiber-based finite element analysis

    Institute of Scientific and Technical Information of China (English)

    Chiara Casarotti; Rui Pinho

    2006-01-01

    It is widely recognized that nonlinear time-history analysis constitutes the most accurate way to simulate the response of structures subjected to strong levels of seismic excitation. This analytical method is based on sound underlying principles and has the capability to reproduce the intrinsic inelastic dynamic behavior of structures. Nonetheless,comparisons with experimental results from large-scale testing of structures are still needed, in order to ensure adequate levels of confidence in this numerical methodology. The fiber modelling approach employed in the current endeavor inherently accounts for geometric nonlinearities and material inelasticity, without a need for calibration of plastic hinges mechanisms,typical in concentrated plasticity models. The resulting combination of analysis accuracy and modelling simplicity, allows thus to overcome the perhaps not fully justifiable sense of complexity associated to nonlinear dynamic analysis. The fiberbased modelling approach is employed in the framework of a finite element program downloaded from the Internet for seismic response analysis of framed structures. The reliability and accuracy of the program are demonstrated by numerically reproducing pseudo-dynamic tests on a four span continuous deck concrete bridge. Modelling assumptions are discussed,together with their implications on numerical results of the nonlinear time-history analyses, which were found to be in good agreement with experimental results.

  15. Finite element modeling of human brain response to football helmet impacts.

    Science.gov (United States)

    Darling, T; Muthuswamy, J; Rajan, S D

    2016-10-01

    The football helmet is used to help mitigate the occurrence of impact-related traumatic (TBI) and minor traumatic brain injuries (mTBI) in the game of American football. While the current helmet design methodology may be adequate for reducing linear acceleration of the head and minimizing TBI, it however has had less effect in minimizing mTBI. The objectives of this study are (a) to develop and validate a coupled finite element (FE) model of a football helmet and the human body, and (b) to assess responses of different regions of the brain to two different impact conditions - frontal oblique and crown impact conditions. The FE helmet model was validated using experimental results of drop tests. Subsequently, the integrated helmet-human body FE model was used to assess the responses of different regions of the brain to impact loads. Strain-rate, strain, and stress measures in the corpus callosum, midbrain, and brain stem were assessed. Results show that maximum strain-rates of 27 and 19 s(-1) are observed in the brain-stem and mid-brain, respectively. This could potentially lead to axonal injuries and neuronal cell death during crown impact conditions. The developed experimental-numerical framework can be used in the study of other helmet-related impact conditions. PMID:26867124

  16. Quantifying crustal response to deep active intrusions with geodesy-based finite element modeling

    Science.gov (United States)

    Henderson, S. T.; Pritchard, M. E.; Elliott, J.

    2013-12-01

    The Altiplano-Puna Volcanic Complex (APVC, 21-24 S, 66-69 W) is a first order feature of the Central Andes Volcanic Arc. The APVC consists of over 10,000 km^3 of dacitic ignimbrites deposited in the late Miocene, making it one of the largest concentrations of silicic volcanism in the world. The persistent and intense magmatic flux in this region has likely contributed to the thickened crust (50-70 km), elevated geotherm (>50 C/km) and extensive partial melt (mass balance between source and sink reservoirs, and require physically realistic rheological parameters of the crust. Modeling is performed with Pylith finite element software on a cylindrical three dimensional domain with a radius of 300 km and depth of 200 km. Our models assume pressurization in a viscoelastic crust, and therefore describe crustal response rather than dynamic processes of fluid creation and motion. Surface deformation timescales are highly dependent on geothermal gradient and source pressurization history. While still inconclusive, the potential for an abrupt end to surface deformation has important implications for the characterization of creep versus relaxation processes occurring in response to deep intrusions. Ultimately, crustal scale numerical models provide a means to check petrologically-derived depths of fluid accumulation, in addition to theoretical estimates of softening that occurs with distributed partial melt. The specific models presented are tuned to the subsurface conditions of the APVC, but may be relevant to arc intrusions below the brittle-ductile transition elsewhere.

  17. OPTIMIZATION OF ULTRASOUND-ASSISTED EXTRACTION OF TOTAL FLAVONOIDS AND ANTIOXIDANT PROPERTIES FROM TRIGONELLA FOENUM-GRAECUM SEEDS WITH RESPONSE SURFACE METHODOLOGY

    Directory of Open Access Journals (Sweden)

    Shaileyee Das

    2013-11-01

    Full Text Available Trigonella foenum-graecum is an annual plant in the family Fabaceae. The distinctive cuboid-shaped, yellow to amber coloured fenugreek seeds are frequently encountered in the cuisines of the Indian subcontinent. In this study, Trigonella foenum-graecum is used as an experimental matrix. Ultrasound-assisted extraction (UAE of total flavonoids from Trigonella foenum-graecum is studied with dual wavelength UV-VIS spectrophotometer. Effects of various factors including ratio of material to liquid, ultrasonic time, methanol concentration and extraction times on extraction yield of total flavonoids are evaluated. Then, optimization of total flavonoid compound (TFC extraction from Trigonella foenum-graecum seed is investigated using response surface methodology (RSM in this paper. Statistical analysis of the experiments indicated that Ratio of material to liquid and methanol concentration significantly affected TFC extraction (p < 0.01. The Box-Behnken experiment design shows that polynomial regression models are in good agreement with the experimental results, with the coefficients of multiple determination of 0.9758 for TFC yield. The optimal conditions for maximum TFC yield are 70% methanol, 50min and 30 (v/w liquid to solid ratios with a 2 time extraction time. Extracts from these conditions showed a moderate antioxidant value from 1,1-diphenyl-2-picrylhydrazyl (DPPH assay, Ferric chloride reducing assay and hydrogen peroxide reducing assay. Fenugreek flavonoids have direct and potent antioxidant activities, might be developed and utilized as natural antioxidant.

  18. Effect of ZnO nanoparticles on Brassica nigra seedlings and stem explants: growth dynamics and antioxidative response

    Directory of Open Access Journals (Sweden)

    Hira eZafar

    2016-04-01

    Full Text Available Nanoparticles (NPs have diverse properties in comparison to respective chemicals due to structure, surface area ratio, morphology, and reactivity. Toxicological effects of metallic NPs to organisms including plants have been reported. However, to the authors’ knowledge there is no report on the effect of NPs on in vitro culture of plant explants. In this study, ZnO NPs at 500-1500 mg/L badly affected Brassica nigra seed germination and seedling growth and raised antioxidative activities and antioxidants concentrations. On the other hand, culturing the stem explants of B. nigra on Murashige and Skoog (MS medium in presence of low concentration of ZnO NPs (1-20 mg/L produced white thin roots with thick root hairs. At 10 mg/L ZnO NPs shoots emergence was also observed. The developed calli/roots showed 79% DPPH (2,2-diphenyl-1-picryl hydrazyl radical scavenging activity at 10 mg/L. While total antioxidant and reducing power potential were also significantly different in presence of ZnO NPs. Non enzymatic antioxidative molecules, phenolics (up to 0.15 µg GAE/mg FW and flavonoids (up to 0.22 µg QE/mg FW, also raised and found NPs concentration dependent. We state that ZnO NPs may induce roots from explants cultured on appropriate medium and can be cultured for production of valuable secondary metabolites.

  19. Pulmonary function response and effects of antioxidant genetic polymorphisms in healthy young adults exposed to low concentration ozone.

    Science.gov (United States)

    Rational: Ozone is known to induce a variety of pulmonary effects including decrement of spirometric lung function and inflammatory reaction, and antioxidant genes are known to play an important role in modulating the effects. It is unclear, however, if such effects may occur at...

  20. The Role of Antioxidant Enzymes in Adaptive Responses to Sheath Blight Infestation under Different Fertilization Rates and Hill Densities

    Directory of Open Access Journals (Sweden)

    Wei Wu

    2014-01-01

    Full Text Available Sheath blight of rice, caused by Rhizoctonia solani, is one of the most devastating rice diseases worldwide. No rice cultivar has been found to be completely resistant to this fungus. Identifying antioxidant enzymes activities (activity of superoxide dismutase (SOD, peroxidase (POD, and catalase (CAT and malondialdehyde content (MDA responding to sheath blight infestation is imperative to understand the defensive mechanism systems of rice. In the present study, two inoculation methods (toothpick and agar block method were tested in double-season rice. Toothpick method had greater lesion length than agar block method in late season. A higher MDA content was found under toothpick method compared with agar block method, which led to greater POD and SOD activities. Dense planting caused higher lesion length resulting in a higher MDA content, which also subsequently stimulated higher POD and SOD activity. Sheath blight severity was significantly related to the activity of antioxidant enzyme during both seasons. The present study implies that rice plants possess a system of antioxidant protective enzymes which helps them in adaptation to sheath blight infection stresses. Several agronomic practices, such as rational use of fertilizers and optimum planting density, involved in regulating antioxidant protective enzyme systems can be regarded as promising strategy to suppress the sheath blight development.

  1. Barley responses to combined waterlogging and salinity stress: separating effects of oxygen deprivation and elemental toxicity.

    Science.gov (United States)

    Zeng, Fanrong; Shabala, Lana; Zhou, Meixue; Zhang, Guoping; Shabala, Sergey

    2013-01-01

    Salinity and waterlogging are two major factors affecting crop production around the world and often occur together (e.g., salt brought to the surface by rising water tables). While the physiological and molecular mechanisms of plant responses to each of these environmental constraints are studied in detail, the mechanisms underlying plant tolerance to their combined stress are much less understood. In this study, whole-plant physiological responses to individual/combined salinity and waterlogging stresses were studied using two barley varieties grown in either vermiculite (semi-hydroponics) or sandy loam. Two weeks of combined salinity and waterlogging treatment significantly decreased plant biomass, chlorophyll content, maximal quantum efficiency of PSII and water content (WC) in both varieties, while the percentage of chlorotic and necrotic leaves and leaf sap osmolality increased. The adverse effects of the combined stresses were much stronger in the waterlogging-sensitive variety Naso Nijo. Compared with salinity stress alone, the combined stress resulted in a 2-fold increase in leaf Na(+), but a 40% decrease in leaf K(+) content. Importantly, the effects of the combined stress were more pronounced in sandy loam compared with vermiculite and correlated with changes in the soil redox potential and accumulation of Mn and Fe in the waterlogged soils. It is concluded that hypoxia alone is not a major factor determining differential plant growth under adverse stress conditions, and that elemental toxicities resulting from changes in soil redox potential have a major impact on genotypic differences in plant physiological and agronomical responses. These results are further discussed in the context of plant breeding for waterlogging stress tolerance. PMID:23967003

  2. A wave finite element-based formulation for computing the forced response of structures involving rectangular flat shells

    OpenAIRE

    Mencik, Jean-Mathieu

    2013-01-01

    International audience The harmonic forced response of structures involving several noncoplanar rectangular flat shells is investigated by using the Wave Finite Element method. Such flat shells are connected along parallel edges where external excitation sources as well as mechanical impedances are likely to occur. Also, they can be connected to one or several coupling elements whose shapes and dynamics can be complex. The dynamic behavior of the connected shells is described by means of n...

  3. A new orphan member of the nuclear hormone receptor superfamily that interacts with a subset of retinoic acid response elements.

    OpenAIRE

    Baes, M.; Gulick, T; Choi, H. S.; Martinoli, M G; Simha, D; Moore, D D

    1994-01-01

    We have identified and characterized a new orphan member of the nuclear hormone receptor superfamily, called MB67, which is predominantly expressed in liver. MB67 binds and transactivates the retinoic acid response elements that control expression of the retinoic acid receptor beta 2 and alcohol dehydrogenase 3 genes, both of which consist of a direct repeat hexamers related to the consensus AGGTCA, separated by 5 bp. MB67 binds these elements as a heterodimer with the 9-cis-retinoic acid rec...

  4. Liver X receptor regulates hepatic nuclear O-GlcNAc signaling and carbohydrate responsive element-binding protein activity

    DEFF Research Database (Denmark)

    Bindesbøll, Christian; Fan, Qiong; Nørgaard, Rikke C;

    2015-01-01

    Liver X receptor (LXR)α and LXRβ play key roles in hepatic de novo lipogenesis through their regulation of lipogenic genes, including sterol regulatory element-binding protein (SREBP)-1c and carbohydrate responsive element-binding protein (ChREBP). LXRs activate lipogenic gene transcription...... metabolic sensors upstream of ChREBP by modulating GK expression, nuclear O-GlcNAc signaling, and ChREBP expression and activity....

  5. Altered Response Hierarchy and Increased T-Cell Breadth upon HIV-1 Conserved Element DNA Vaccination in Macaques

    OpenAIRE

    Viraj Kulkarni; Antonio Valentin; Margherita Rosati; Candido Alicea; Singh, Ashish K; Rashmi Jalah; Broderick, Kate E.; Sardesai, Niranjan Y.; Sylvie Le Gall; Beatriz Mothe; Christian Brander; Morgane Rolland; Mullins, James I.; Pavlakis, George N.; Felber, Barbara K.

    2014-01-01

    HIV sequence diversity and potential decoy epitopes are hurdles in the development of an effective AIDS vaccine. A DNA vaccine candidate comprising of highly conserved p24(gag) elements (CE) induced robust immunity in all 10 vaccinated macaques, whereas full-length gag DNA vaccination elicited responses to these conserved elements in only 5 of 11 animals, targeting fewer CE per animal. Importantly, boosting CE-primed macaques with DNA expressing full-length p55(gag) increased both magnitude o...

  6. Application of an online post-column derivatization HPLC-DPPH assay to detect compounds responsible for antioxidant activity in Sonchus oleraceus L. leaf extracts

    DEFF Research Database (Denmark)

    Ou, Zong-Quan; Schmierer, David M; Rades, Thomas;

    2013-01-01

    To use an online assay to identify key antioxidants in Sonchus oleraceus leaf extracts and to investigate the effect of leaf position and extraction conditions on antioxidant concentration and activity.......To use an online assay to identify key antioxidants in Sonchus oleraceus leaf extracts and to investigate the effect of leaf position and extraction conditions on antioxidant concentration and activity....

  7. Oxidative Stress and Erythrocyte Membrane Responses During Sarcoptic Mange in Sheep: Evaluating Bio-Organic Therapy and its Supplementation with Antioxidant Tocopherol.

    Directory of Open Access Journals (Sweden)

    Umesh Dimri

    2005-01-01

    Full Text Available Sarcoptic mange in sheep, causes heavy losses in quantity and quality of wool and meat production.The present investigation aimed at evaluating the oxidative stress-antioxidant defense and erythrocytic membrane responses during sarcoptic mange in sheep.A bio-organic therapy (BT was evaluated for its efficacy. Tocopherol was assessed for its antioxidant adjunctive potential. Materials and Methods: Nineteen sheep with sarcoptic mange (aged 9-12 months, with lesions ascribed to Sarcoptes scabiei var. ovis were divided into 2 groups of 8 (group1 and 11(group2 respectively.Group1 was sprayed with the BT (Topicure: Natural Remedies Private Limited, Bangalore, India; containing extracts and distillates of Eucalyptus globulus, Cedrus deodara and Pinus longifolia.In Group2, BT plus tocopherol (E-care Se: Health Line Private Limited, Bangalore, India; containing tocopherol-50mg, selenium-1.5mg; two intramuscular injections at 7 days gap were advocated.The animals were free from other pathogenic microorganisms.Ecto-parasites were identified by standard procedures.(aResponse to treatment: was noted each day through grade codes (0 to 4.(bMite count:Skin scrapings were examined for mites on 0,1,2,3,4,5,6,7,8,9,10,14,21 and 28 days post treatment (PT.(cOxidative stress- antioxidant defense, erythrocyte membrane responses: In erythrocytes (days ¿0¿ and 28 PT, lipid peroxidation (LP, reduced glutathione (GSH, catalase, superoxide dismutase, glutathione-s-transferase, adenosine triphosphatases (total ATPase, Na+ K+-`ATPase and Mg2+-ATPase & protein were estimated.(dHaematology:total erythrocyte count (TEC, haemoglobin (Hb and hematocrit (H were estimated in blood (days 0 and 28. (e Statistical analysis was as per standard procedures. Results: (a Clinical observations: BT was effective and with tocopherol it was effective just within 2 days of start of therapy with an effectiveness of 77.5%. (b Mite count: BT was good and with tocopherol it was effective against

  8. Effect of the ingestion of a mousse with cinnamon C. Burmannii on the postprandial blood glucose response of healthy subjects and its antioxidant power

    OpenAIRE

    Amaral, Catarina Medeiros

    2013-01-01

    Dissertação para obtenção do grau de Mestre em Nutrição Clínica Background: Cinnamon has been shown to reduce postprandial glycaemia and enhance insulin sensitivity in healthy adults. Aims: To study the effect of C. burmannii on the postprandial blood glucose response of healthy subjects and its antioxidant capacity in a semi-solid food. Design: Twenty four apparently healthy subjects participated in this study. They were randomly assigned in group A (reference meal) or grou...

  9. A chromatin insulator driving three-dimensional Polycomb response element (PRE) contacts and Polycomb association with the chromatin fiber

    DEFF Research Database (Denmark)

    Comet, Itys; Schuettengruber, Bernd; Sexton, Tom;

    2011-01-01

    to insulate genes from regulatory elements or to take part in long-distance interactions. Using a high-resolution chromatin conformation capture (H3C) method, we show that the Drosophila gypsy insulator behaves as a conformational chromatin border that is able to prohibit contacts between a Polycomb response...... element (PRE) and a distal promoter. On the other hand, two spaced gypsy elements form a chromatin loop that is able to bring an upstream PRE in contact with a downstream gene to mediate its repression. Chromatin immunoprecipitation (ChIP) profiles of the Polycomb protein and its associated H3K27me3...

  10. Identification of a peroxisome proliferator responsive element (PPRE)-like cis-element in mouse plasminogen activator inhibitor-1 gene promoter

    International Nuclear Information System (INIS)

    PAI-1 is expressed and secreted by adipose tissue which may mediate the pathogenesis of obesity-associated cardiovascular complications. Evidence is presented in this report that PAI-1 is not expressed by preadipocyte, but significantly induced during 3T3-L1 adipocyte differentiation and the PAI-1 expression correlates with the induction of peroxisome proliferator-activated receptor γ (PPARγ). A peroxisome proliferator responsive element (PPRE)-like cis-element (-206TCCCCCATGCCCT-194) is identified in the mouse PAI-1 gene promoter by electrophoretic mobility shift assay (EMSA) combined with transient transfection experiments; the PPRE-like cis-element forms a specific DNA-protein complex only with adipocyte nuclear extracts, not with preadipocyte nuclear extracts; the DNA-protein complex can be totally competed away by non-labeled consensus PPRE, and can be supershifted with PPARγ antibody. Mutation of this PPRE-like cis-element can abolish the transactivation of mouse PAI-1 promoter mediated by PPARγ. Specific PPARγ ligand Pioglitazone can significantly induce the PAI-1 expression, and stimulate the secretion of PAI-1 into medium

  11. Icariin upregulates phosphorylated cyclic adenosine monophosphate response element binding protein levels in the hippocampus of the senescence- accelerated mouse

    Institute of Scientific and Technical Information of China (English)

    Zhanwei Zhang; Ting Zhang; Keli Dong

    2012-01-01

    At 8 weeks after intragastric administration of icariin to senescence-accelerated mice (P8 strain), Morris water maze results showed that escape latency was shortened, and the number of platform crossings was increased. Immunohistochemical staining and western blot assay detected signifi-cantly increased levels of cyclic adenosine monophosphate response element binding protein. These results suggest that icariin upregulates phosphorylated cyclic adenosine monophosphate response element binding protein levels and improves learning and memory functions in hippo-campus of the senescence-accelerated mouse.

  12. Poor antioxidant status exacerbates oxidative stress and inflammatory response to Pseudomonas aeruginosa lung infection in Guinea Pigs

    DEFF Research Database (Denmark)

    Jensen, Peter Østrup; Lykkesfeldt, Jens; Bjarnsholt, Thomas;

    2012-01-01

    Considerable evidence supports the presence of oxidative stress in cystic fibrosis (CF). The disease has long been associated with both increased production of reactive oxygen species and impaired antioxidant status, in particular during the chronic pulmonary infection with Pseudomonas aeruginosa...... of oxidative stress. The aim of our study was to investigate the consequences of a 7-day biofilm-grown P. aeruginosa lung infection in 3-month-old guinea pigs receiving either ASC-sufficient or ASC-deficient diet for at least 2 months. The animals receiving ASC-deficient diet showed significantly higher......, which is the main cause of morbidity and mortality in CF. Guinea pigs are unable to synthesize ascorbate (ASC) or vitamin C, a major antioxidant of the lung, and thus like human beings rely on its presence in the diet. On this basis, guinea pigs receiving ASC-deficient diet have been used as a model...

  13. Phenolics and Flavonoids Compounds, Phenylanine Ammonia Lyase and Antioxidant Activity Responses to Elevated CO2 in Labisia pumila (Myrisinaceae)

    OpenAIRE

    Jaafar, Hawa Z. E.; Ehsan Karimi; Mohd Hafiz Ibrahim

    2012-01-01

    A split plot 3 × 3 experiment was designed to examine the impact of three concentrations of CO2 (400, 800 and 1,200 µmol·mol−1) on the phenolic and flavonoid compound profiles, phenylalanine ammonia lyase (PAL) and antioxidant activity in three varieties of Labisia pumila Benth. (var. alata, pumila and lanceolata) after 15 weeks of exposure. HPLC analysis revealed ...

  14. Dose-response effects of lycopene on selected drug-metabolizing and antioxidant enzymes in the rat

    DEFF Research Database (Denmark)

    Breinholt, V.; Lauridsen, S. T.; Daneshvar, B.;

    2000-01-01

    treatment. The activity of superoxide dismutase was thus significantly induced at lycopene doses of 0.005 and 0.05 g/kg b.w, whereas glutathione reductase and glutathione peroxidase was only induced at the 0.005 g/kg b.w. per day dose. For all antioxidant enzymes investigated, the activities seemed......-metabolizing enzymes involved in the protection against oxidative stress and cancer. The fact that these enzymatic activities are induced at all of these very low plasma levels, could be taken to suggest that modulation of antioxidant and drug-metabolizing enzymes map indeed be relevant to humans, which in general......The administration of lycopene to female rats at doses ranging from 0.001 to 0.1 g/kg b.w, per day for 2 weeks was found to alter the drug-metabolizing capacity and antioxidant status of the exposed animals. An investigation of four cytochrome P450-dependent enzymes revealed that benzyloxyresorufin...

  15. Physiological responses of Brassica napus to fulvic acid under water stress:Chlorophyll a fluorescence and antioxidant enzyme activity

    Institute of Scientific and Technical Information of China (English)

    Ramin Lotfi; Mohammad Pessarakli; Puriya Gharavi-Kouchebagh; Hossein Khoshvaghti

    2015-01-01

    The ameliorative effect of fulvic acid (0, 300, and 600 mg L−1) on photosystem II and antioxidant enzyme activity of the rapeseed (Brassica napus L.) plant under water stress (60, 100, and 140 mm evaporation from class A pan) was studied using split plots in a randomized complete block design with three replications. Results indicated that application of fulvic acid (FA) improved the maximum quantum efficiency of PSII (Fv/Fm) and performance index (PI) of plants under both well-watered and limited-water conditions. The time span from Fo to Fm and the energy necessary for the closure of all reaction centers was significantly increased, but the size of the plastoquinone pool was reduced with increasing water stress levels. Plants treated with FA had higher peroxidase and catalase activities under all irrigation conditions. Activities of ascorbate peroxidase and superoxide dismutase in plants increased with increasing water stress. Malondialdehyde increased under severe water stress, but application of FA significantly decreased lipid peroxidation. Production of reactive oxygen species (ROS) is a common phenomenon in plants under stress. Under this condition, the balance between the production of ROS and the quenching activity of antioxidants is upset, often resulting in oxidative damage. In this study, application of FA significantly increased fluorescence of chlorophyll a, inhibiting ROS production and enhancing antioxidant enzymes activity that destroyed ROS. Thus, ROS in plant cells was reduced under water stress by application of FA and consequently lipid peroxidation was reduced.

  16. Physiological responses of Brassica napus to fulvic acid under water stress: Chlorophyll a fluorescence and antioxidant enzyme activity

    Institute of Scientific and Technical Information of China (English)

    Ramin; Lotfi; Mohammad; Pessarakli; Puriya; Gharavi-Kouchebagh; Hossein; Khoshvaghti

    2015-01-01

    The ameliorative effect of fulvic acid(0, 300, and 600 mg L-1) on photosystem II and antioxidant enzyme activity of the rapeseed(Brassica napus L.) plant under water stress(60, 100, and 140 mm evaporation from class A pan) was studied using split plots in a randomized complete block design with three replications. Results indicated that application of fulvic acid(FA) improved the maximum quantum efficiency of PSII(Fv/Fm)and performance index(PI) of plants under both well-watered and limited-water conditions. The time span from Foto Fmand the energy necessary for the closure of all reaction centers was significantly increased, but the size of the plastoquinone pool was reduced with increasing water stress levels. Plants treated with FA had higher peroxidase and catalase activities under all irrigation conditions. Activities of ascorbate peroxidase and superoxide dismutase in plants increased with increasing water stress. Malondialdehyde increased under severe water stress, but application of FA significantly decreased lipid peroxidation. Production of reactive oxygen species(ROS) is a common phenomenon in plants under stress. Under this condition, the balance between the production of ROS and the quenching activity of antioxidants is upset, often resulting in oxidative damage. In this study, application of FA significantly increased fluorescence of chlorophyll a, inhibiting ROS production and enhancing antioxidant enzymes activity that destroyed ROS. Thus, ROS in plant cells was reduced under water stress by application of FA and consequently lipid peroxidation was reduced.

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

    Science.gov (United States)

    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 (Pcopper (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

  18. Antioxidant biochemical responses to long-term copper exposure in Bathymodiolus azoricus from Menez-Gwen hydrothermal vent.

    Science.gov (United States)

    Company, Rui; Serafim, Angela; Cosson, Richard P; Fiala-Médioni, Aline; Camus, Lionel; Colaço, Ana; Serrão-Santos, Ricardo; Bebianno, Maria João

    2008-01-25

    Copper (Cu) is essential to various physiological processes in marine organisms. However, at high concentrations this redox-active transition metal may enhance the formation of reactive oxygen species (ROS) and subsequently initiate oxidative damage. High concentrations of Cu may increase oxidative damage to lipids, proteins and DNA. Bathymodiolus azoricus is a Mytilid bivalve very common in hydrothermal environments near the Azores Triple Junction continuously exposed to high metal concentrations, including Cu, emanating from the vent fluids. The knowledge of antioxidant defence system and other stress related biomarkers in these organisms is still scarce. The aim of this work was to study the effect of Cu (25 microg l(-1); 24 days exposure; 6 days depuration) on the antioxidant stress biomarkers in the gills and mantle of B. azoricus. The expression of stress related biomarkers was tissue-dependent and results suggest that other factors than metal exposure may influence stress biomarkers, since little variation in antioxidant enzymes activities, MT concentrations, LPO and total oxyradical scavenging capacity (TOSC) occurred in both control and Cu-exposed mussels. Moreover, there is a general tendency for these parameters to increase with time, in both control and Cu-exposed mussels, suggesting that reactive oxygen species (ROS) formation is not metal dependent, and may be related with poor physiological conditions of the animals after long periods in adverse conditions compared to those in hydrothermal environments.

  19. Mitochondrial structural and antioxidant system responses to aging in oat (Avena sativa L.) seeds with different moisture contents.

    Science.gov (United States)

    Xia, Fangshan; Wang, Xianguo; Li, Manli; Mao, Peisheng

    2015-09-01

    We observed the relationship between lifespan and mitochondria, including antioxidant systems, ultrastructure, and the hydrogen peroxide and malondialdehyde contents in 4 h imbibed oat (Avena sativa L.) seeds that were aged with different moisture contents (4%, 10% and 16%) for 0 (the control), 8, 16, 24, 32 and 40 d at 45 °C. The results showed that the decline in the oat seed vigor and in the integrity of the mitochondrial ultrastructure occurred during the aging process, and that these changes were enhanced by higher moisture contents. Mitochondrial antioxidants in imbibed oat seeds aged with a 4% moisture content were maintained at higher levels than imbibed oat seeds aged with a 10% and 16% moisture content. These results indicated that the levels of mitochondrial antioxidants and malondialdehyde after imbibition were related to the integrity of the mitochondrial membrane in aged oat seeds. The scavenging role of mitochondrial superoxide dismutase was inhibited in imbibed oat seeds aged at the early stage. Monodehydroascorbate reductase and dehydroascorbate reductase played more important roles than glutathione reductase in ascorbate regeneration in aged oat seeds during imbibition.

  20. Physiological responses of Brassica napus to fulvic acid under water stress: Chlorophyll a fluorescence and antioxidant enzyme activity

    Directory of Open Access Journals (Sweden)

    Ramin Lotfi

    2015-10-01

    Full Text Available The ameliorative effect of fulvic acid (0, 300, and 600 mg L− 1 on photosystem II and antioxidant enzyme activity of the rapeseed (Brassica napus L. plant under water stress (60, 100, and 140 mm evaporation from class A pan was studied using split plots in a randomized complete block design with three replications. Results indicated that application of fulvic acid (FA improved the maximum quantum efficiency of PSII (Fv/Fm and performance index (PI of plants under both well-watered and limited-water conditions. The time span from Fo to Fm and the energy necessary for the closure of all reaction centers was significantly increased, but the size of the plastoquinone pool was reduced with increasing water stress levels. Plants treated with FA had higher peroxidase and catalase activities under all irrigation conditions. Activities of ascorbate peroxidase and superoxide dismutase in plants increased with increasing water stress. Malondialdehyde increased under severe water stress, but application of FA significantly decreased lipid peroxidation. Production of reactive oxygen species (ROS is a common phenomenon in plants under stress. Under this condition, the balance between the production of ROS and the quenching activity of antioxidants is upset, often resulting in oxidative damage. In this study, application of FA significantly increased fluorescence of chlorophyll a, inhibiting ROS production and enhancing antioxidant enzymes activity that destroyed ROS. Thus, ROS in plant cells was reduced under water stress by application of FA and consequently lipid peroxidation was reduced.

  1. Killing of Brain Tumor Cells by Hypoxia-Responsive Element Mediated Expression of BAX

    Directory of Open Access Journals (Sweden)

    Hangjun Ruan

    1999-11-01

    Full Text Available The presence of radioresistant hypoxic cells in human brain tumors limits the overall effectiveness of conventional fractionated radiation therapy. Tumor-specific therapies that target hypoxic cells are clearly needed. We have investigated the expression of suicide genes under hypoxia by a hypoxia-responsive element (HRE, which can be activated through hypoxia-inducible factor-1 (HIF-1. We transfected plasmids containing multiple copies of HIRE into U-87 MG and U-251 MG-NCI human brain tumor cells and tested their ability to induce LacZ gene expression under anoxia. Gene expression under anoxia versus oxia was increased about 12-fold for U-87 MG cells and about fourfold for U-251 MG-NCI cells. At intermediate hypoxic conditions, increased LacZ gene expression in U-87 MG cells was induced by the plasmid that contained three HREs, but not by the plasmid with two HREs. Lastly, when we placed a suicide gene BAX under the control of HREs, cells transfected with the BAX plasmids were preferentially killed through apoptosis under anoxia. Our studies demonstrate that HRE-regulated gene expression is active in brain tumor cells, and that the amount of increased gene expression obtained is dependent on the cell line, the HIRE copy number, and the degree of hypoxia.

  2. VIP1 response elements mediate mitogen-activated protein kinase 3-induced stress gene expression.

    Science.gov (United States)

    Pitzschke, Andrea; Djamei, Armin; Teige, Markus; Hirt, Heribert

    2009-10-27

    The plant pathogen Agrobacterium tumefaciens transforms plant cells by delivering its T-DNA into the plant cell nucleus where it integrates into the plant genome and causes tumor formation. A key role of VirE2-interacting protein 1 (VIP1) in the nuclear import of T-DNA during Agrobacterium-mediated plant transformation has been unravelled and VIP1 was shown to undergo nuclear localization upon phosphorylation by the mitogen-activated protein kinase MPK3. Here, we provide evidence that VIP1 encodes a functional bZIP transcription factor that stimulates stress-dependent gene expression by binding to VIP1 response elements (VREs), a DNA hexamer motif. VREs are overrepresented in promoters responding to activation of the MPK3 pathway such as Trxh8 and MYB44. Accordingly, plants overexpressing VIP1 accumulate high levels of Trxh8 and MYB44 transcripts, whereas stress-induced expression of these genes is impaired in mpk3 mutants. Trxh8 and MYB44 promoters are activated by VIP1 in a VRE-dependent manner. VIP1 strongly enhances expression from a synthetic promoter harboring multiple VRE copies and directly interacts with VREs in vitro and in vivo. Chromatin immunoprecipitation assays of the MYB44 promoter confirm that VIP1 binding to VREs is enhanced under conditions of MPK3 pathway stimulation. These results provide molecular insight into the cellular mechanism of target gene regulation by the MPK3 pathway. PMID:19820165

  3. cAMP-response-element-binding protein positively regulates breast cancer metastasis and subsequent bone destruction

    Energy Technology Data Exchange (ETDEWEB)

    Son, Jieun; Lee, Jong-Ho; Kim, Ha-Neui; Ha, Hyunil, E-mail: hyunil74@hotmail.com; Lee, Zang Hee, E-mail: zang1959@snu.ac.kr

    2010-07-23

    Research highlights: {yields} CREB is highly expressed in advanced breast cancer cells. {yields} Tumor-related factors such as TGF-{beta} further elevate CREB expression. {yields} CREB upregulation stimulates metastatic potential of breast cancer cells. {yields} CREB signaling is required for breast cancer-induced bone destruction. -- Abstract: cAMP-response-element-binding protein (CREB) signaling has been reported to be associated with cancer development and poor clinical outcome in various types of cancer. However, it remains to be elucidated whether CREB is involved in breast cancer development and osteotropism. Here, we found that metastatic MDA-MB-231 breast cancer cells exhibited higher CREB expression than did non-metastatic MCF-7 cells and that CREB expression was further increased by several soluble factors linked to cancer progression, such as IL-1, IGF-1, and TGF-{beta}. Using wild-type CREB and a dominant-negative form (K-CREB), we found that CREB signaling positively regulated the proliferation, migration, and invasion of MDA-MB-231 cells. In addition, K-CREB prevented MDA-MB-231 cell-induced osteolytic lesions in a mouse model of cancer metastasis. Furthermore, CREB signaling in cancer cells regulated the gene expression of PTHrP, MMPs, and OPG, which are closely involved in cancer metastasis and bone destruction. These results indicate that breast cancer cells acquire CREB overexpression during their development and that this CREB upregulation plays an important role in multiple steps of breast cancer bone metastasis.

  4. A peroxisome proliferator response elements regulatory system in xenopus oocytes and its application

    Institute of Scientific and Technical Information of China (English)

    YAN Jin; FAN Chun-lei; WO Xing-de; GAO Li-ping

    2005-01-01

    Background Peroxisome proliferator-activated receptor-gamma (PPARγ) is a kind of ligand-activated transcription factors binding to peroxisome proliferator response element (PPRE), a specific recognition site. It is thought to play a critical role in glucose and lipid metabolism and in inflammation control. The aim of this study was to establish a new cellular model for the quick screening of lipid-lowering drugs, which may be effective as PPAR-γ ligands on the PPRE-mediated pathway regulatory system. Methods Two plasmids were constructed: pXOE-PPARγ, in which the human PPARγ gene was in the downstream of TFⅢA gene promoter, and pLXRN-PPRE-d2EGFP, in which the enhanced green fluorescent protein (EGFP) gene was subcloned into PPRE. The xenopus oocytes were injected with these two plamids, and consequently treated with prostaglandin E1, pioglitazone, and different kinds of lipid-lowering drugs. After 3 days, the oocytes were observed under a fluorescence microscope. To confirm the drug action,we injected pXOE-PPARγ plasmid into the oocytes, which then treated with prostaglandin E1and Hawthorn flavonoids. The mass of expressed lipoprotein lipase (LPL) in the cells was determined by enzyme labeling linked immunosorbent assay (ELISA).Conclusions It is possible to establish a PPRE regulatory EGFP reporter system in xenopus oocytes to monitor the activity of PPARγ ligand. Hawthorn flavonoids can increase the expression of gene downsteam of PPRE by effect on the PPRE pathway regulatory system.

  5. Pycnogenol® inhibits lipid accumulation in 3T3-L1 adipocytes with the modulation of reactive oxygen species (ROS) production associated with antioxidant enzyme responses.

    Science.gov (United States)

    Lee, Ok-Hwan; Seo, Min-Jung; Choi, Hyeon-Son; Lee, Boo-Yong

    2012-03-01

    Pycnogenol® is a group of flavonoids with antioxidant effects. Adipogenesis is the process of adipocyte differentiation. It causes the increase of lipids as well as ROS (reactive oxygen species). Lipid accumulation and ROS production were determined in 3 T3-L1 adipocyte, and the effect of Pycnogenol® was evaluated. Lipid accumulation was elevated in adipocyte treated with hydrogen peroxide, one of the ROS. Pycnogenol® showed an inhibitory effect on the lipid accumulation and ROS production during the adipogenesis. We also investigated the molecular events associated with ROS production and lipid accumulation. Our results showed that Pycnogenol® inhibited the mRNA expression of pro-oxidant enzymes, such as NOX4 (NADPH (nicotinamide adenine dinucleotide phosphate hydrogen) oxidase 4), and the NADPH-producing G6PDH (glucose-6-phosphate dehydrogenase) enzyme. In addition, Pycnogenol® suppressed the mRNA abundance of adipogenic transcription factors, PPAR-γ (peroxisome proliferator-activated receptor γ) and C/EBP-α (CCAAT/enhancer binding protein α), and their target gene, aP2 (adipocyte protein 2) responsible for fatty acid transportation. On the other hand, Pycnogenol® increased the abundance of antioxidant proteins such as Cu/Zn-SOD (copper-zinc superoxide dismutase), Mn-SOD (manganese superoxide dismutase), GPx (glutathione peroxidase) and GR (glutathione reductase). Our results suggest that Pycnogenol® inhibits lipid accumulation and ROS production by regulating adipogenic gene expression and pro-/antioxidant enzyme responses in adipocytes. PMID:21796705

  6. Proteomic expression profiling of Haemophilus influenzae grown in pooled human sputum from adults with chronic obstructive pulmonary disease reveal antioxidant and stress responses

    Directory of Open Access Journals (Sweden)

    Brauer Aimee L

    2010-06-01

    Full Text Available Abstract Background Nontypeable Haemophilus influenzae colonizes and infects the airways of adults with chronic obstructive pulmonary disease, the fourth most common cause of death worldwide.Thus, H. influenzae, an exclusively human pathogen, has adapted to survive in the hostile environment of the human airways.To characterize proteins expressed by H. influenzae in the airways, a prototype strain was grown in pooled human sputum to simulate conditions in the human respiratory tract.The proteins from whole bacterial cell lysates were solubilized with a strong buffer and then quantitatively cleaned with an optimized precipitation/on-pellet enzymatic digestion procedure.Proteomic profiling was accomplished by Nano-flow liquid chromatography/mass spectroscopy with low void volume and high separation efficiency with a shallow, long gradient. Results A total of 1402 proteins were identified with high confidence, including 170 proteins that were encoded by genes that are annotated as conserved hypothetical proteins.Thirty-one proteins were present in greater abundance in sputum-grown conditions at a ratio of > 1.5 compared to chemically defined media.These included 8 anti-oxidant and 5 stress-related proteins, suggesting that expression of antioxidant activity and stress responses is important for survival in the airways.Four proteins involved in uptake of divalent anions and 9 proteins that function in uptake of various molecules were present in greater abundance in sputum-grown conditions. Conclusions Proteomic expression profiling of H. influenzae grown in pooled human sputum revealed increased expression of antioxidant, stress-response proteins and cofactor and nutrient uptake systems compared to media grown cells.These observations suggest that H. influenzae adapts to the oxidative and nutritionally limited conditions of the airways in adults with chronic obstructive pulmonary disease by increasing expression of molecules necessary for survival

  7. Nitric oxide is involved in dehydration/drought tolerance in Poncirus trifoliata seedlings through regulation of antioxidant systems and stomatal response.

    Science.gov (United States)

    Fan, Qi-Jun; Liu, Ji-Hong

    2012-01-01

    Nitric oxide (NO) is a component of the repertoire of signals implicated in plant responses to environmental stimuli. In the present study, we investigated the effects of exogenous application of NO-releasing donor sodium nitroprusside (SNP) and nitric oxide synthase inhibitor N(G)-nitro-L-arginine-methyl ester (L-NAME) on dehydration and drought tolerance of Poncirus trifoliata. The endogenous NO level was enhanced by SNP pretreatment, but decreased by L-NAME, in the hydroponic or potted plants with or without stresses. Under dehydration, leaves from the SNP-treated hydroponic seedlings displayed less water loss, lower electrolyte leakage and reactive oxygen species accumulation, higher antioxidant enzyme activities and smaller stomatal apertures as compared with the control (treated with water). In addition, pretreatment of the potted plants with SNP resulted in lower electrolyte leakage, higher chlorophyll content, smaller stomatal conductance and larger photosynthetic rate relative to the control. By contrast, the inhibitor treatment changed these physiological attributes or phenotypes in an opposite way. These results indicate that NO in the form of SNP enhanced dehydration and drought tolerance, whereas the inhibitor makes the leaves or plants more sensitive to the stresses. The stress tolerance by NO might be ascribed to a combinatory effect of modulation of stomatal response and activation of the antioxidant enzymes. Taken together, NO is involved in dehydration and drought tolerance of P. trifoliata, implying that manipulation of this signal molecule may provide a practical approach to combat the environmental stresses. PMID:21938448

  8. The Indirect Boundary Element Method (IBEM) for Seismic Response of Topographical Irregularities in Layered Media

    Science.gov (United States)

    Contreras Zazueta, M. A.; Perton, M.; Sanchez-Sesma, F. J.; Sánchez-Alvaro, E.

    2013-12-01

    The seismic hazard assessment of extended developments, such as a dam, a bridge or a pipeline, needs the strong ground motion simulation taking into account the effects of surface geology. In many cases the incoming wave field can be obtained from attenuation relations or simulations for layered media using Discrete Wave Number (DWN). Sometimes there is a need to include in simulations the seismic source as well. A number of methods to solve these problems have been developed. Among them the Finite Element and Finite Difference Methods (FEM and FDM) are generally preferred because of the facility of use. Nevertheless, the analysis of realistic dynamic loading induced by earthquakes requires a thinner mesh of the entire domain to consider high frequencies. Consequently this may imply a high computational cost. The Indirect Boundary Element Method (IBEM) can also be employed. Here it is used to study the response of a site to historical seismic activity. This method is particularly suited to model wave propagation through wide areas as it requires only the meshing of boundaries. Moreover, it is well suited to represent finely the diffraction that can occur on a fault. However, the IBEM has been applied mainly to simple geometrical configurations. In this communication significant refinements of the formulation are presented. Using IBEM we can simulate wave propagation in complex geometrical configurations such as a stratified medium crossed by thin faults or having a complex topography. Two main developments are here described; one integrates the DWN method inside the IBEM in order to represent the Green's functions of stratified media with relatively low computational cost but assuming unbounded parallel flat layers, and the other is the extension of IBEM to deal with multi-regions in contact which allows more versatility with a higher computational cost compared to the first one but still minor to an equivalent FEM formulation. The two approaches are fully

  9. Non-linear finite element analysis for prediction of seismic response of buildings considering soil-structure interaction

    OpenAIRE

    E. Çelebi; F. Göktepe; Karahan, N

    2012-01-01

    The objective of this paper focuses primarily on the numerical approach based on two-dimensional (2-D) finite element method for analysis of the seismic response of infinite soil-structure interaction (SSI) system. This study is performed by a series of different scenarios that involved comprehensive parametric analyses including the effects of realistic material properties of the underlying soil on the structural response quantities. Viscous artificial boundaries, simulating the process of w...

  10. Initial response and subsequent course of Crohn's disease treated with elemental diet or prednisolone.

    OpenAIRE

    Gorard, D A; Hunt, J. B.; Payne-James, J J; Palmer, K R; Rees, R. G.; Clark, M L; Farthing, M. J.; Misiewicz, J J; Silk, D. B.

    1993-01-01

    Elemental diet is as effective as corticosteroids in the treatment of previously untreated Crohn's disease. It is unclear whether a poor nutritional state is a prerequisite for efficacy of elemental diet, whether previously treated patients respond as well, or how duration of remission using elemental diet compares with corticosteroid induced remission. Forty two patients with active Crohn's disease were stratified for nutritional state and randomised to receive Vivonex TEN 2.1 l/day for four...

  11. Effects of germination and high hydrostatic pressure processing on mineral elements, amino acids and antioxidants in vitro bioaccessibility, as well as starch digestibility in brown rice (Oryza sativa L.).

    Science.gov (United States)

    Xia, Qiang; Wang, Liping; Xu, Congcong; Mei, Jun; Li, Yunfei

    2017-01-01

    The effects of germination and high hydrostatic pressure (HHP) processing on the in vitro bioaccessibility of mineral elements, amino acids (AAs), antioxidants and starch in brown rice (BR) were investigated. Germinated BR (GBR) was obtained by incubating at 37°C for 36h and then subjected to HHP treatments at 0.1, 100, 300 and 500MPa for 10min. The in vitro bioaccessibility of calcium and copper was increased by 12.59-52.17% and 2.87-23.06% after HHP, respectively, but bioaccessible iron was decreased. In addition, HHP significantly improved individual AAs, particularly indispensable AAs and gama-aminobutyric acid, as well as bioaccessible total antioxidant activities and starch resistance to enzymatic hydrolysis. However, germination greatly increased starch digestibility. Atomic force microscopy characterization suggested an obvious structural change in bran fraction at pressures above 300MPa. These results can help to understand the effects of germination and HHP technologies on nutrients bioaccessibility and develop appropriate processing conditions. PMID:27507507

  12. Replacement of inorganic zinc with lower levels of organic zinc (zinc nicotinate on performance, hematological and serum biochemical constituents, antioxidants status, and immune responses in rats

    Directory of Open Access Journals (Sweden)

    D. Nagalakshmi

    2015-09-01

    Full Text Available Aim: A study was undertaken to investigate the effect of organic zinc (zinc nicotinate, Zn-nic supplementation (6, 9, and 12 ppm compared to inorganic zinc (12 ppm on growth performance, hematology, serum biochemical constituents oxidative stress, and immunity in weaned female Sprague–Dawley rats. Material and Methods: A 48 weaned rats (285.20±1.95 g were randomly distributed to 4 dietary treatments with 6 replicates in each and reared in polypropylene cages for 10 weeks. Basal diet (BD was formulated with purified ingredients without zinc (Zn. Four dietary treatments were prepared by adding 12 ppm Zn from ZnCO3 (control and 6, 9, and 12 ppm Zn from Zn-nic to the BD. On 42nd day, blood was collected by retro-orbital puncture for analyzing hematological constituents, glucose, cholesterol, alkaline phosphatase, total protein, albumin, and globulin and antioxidant enzyme activities. At 43rd day, rats were antigenically challenged with sheep red blood cell (RBC to assess humoral immune response and on 70th day cell-mediated immune response. Results: Weekly body weight gains, daily feed intake, blood hematological constituents (white blood cell, RBC, hemoglobin concentration, packed cell volume, mean corpuscular volume, lymphocyte, monocyte, and granulocyte concentration and serum glucose, total protein levels were comparable among the rats feed Zn from ZnCO3 and Zn-nic (6, 9, and 12 ppm. Serum cholesterol reduced with organic Zn supplementation at either concentration (6-12 ppm. Serum globulin concentration reduced (p<0.05 with 6 ppm Zn-nic supplementation compared to other dietary treatments. Lipid peroxidation lowered (p<0.05 reduced with 12 ppm organic Zn; thiobarbituric acid reacting substances and protein carbonyls concentrations in liver reduced (p<0.05 with 9 and 12 ppm levels of organic Zn supplementation compared to 12 ppm Zn supplementation from inorganic source. RBC catalase and glutathione peroxidase enzymes activities were highest (p

  13. Effect of Supplementing Organic Forms of Zinc, Selenium and Chromium on Performance, Anti-Oxidant and Immune Responses in Broiler Chicken Reared in Tropical Summer.

    Science.gov (United States)

    Rao, S V Rama; Prakash, B; Raju, M V L N; Panda, A K; Kumari, R K; Reddy, E Pradeep Kumar

    2016-08-01

    Two experiments were conducted to study the effect of supplementing organic forms of zinc (Zn), selenium (Se) and chromium (Cr) on performance, anti-oxidant activities and immune responses in broiler chickens from 1 to 21 days of age, which were reared in cyclic heat-stressed condition under tropical summer in open-sided poultry house. A total of 200 (experiment I) and 450-day-old (experiment II) broiler male chicks (Cobb 400) were randomly distributed in stainless steel battery brooders (610 mm × 762 mm × 475 mm) at the rate of five birds per pen. A maize-soybean meal-based control diet (CD) containing recommended (Vencobb 400, Broiler Management Guide) concentrations of inorganic trace minerals and other nutrients was prepared. The CD was supplemented individually with organic form of selenium (Se, 0.30 mg/kg), chromium (Cr, 2 mg/kg) and zinc (Zn, 40 mg/kg) in experiment I. In experiment II, two concentrations of each Zn (20 and 40 mg/kg), Se (0.15 and 0.30 mg/kg) and Cr (1 and 2 mg/kg) were supplemented to the basal diet in 2 × 2 × 2 factorial design. A group without supplementing inorganic trace minerals was maintained as control group in both experiments. Each diet was allotted randomly to ten replicates in both experiments and fed ad libitum from 1 to 21 days of age. At 19th day of age, blood samples were collected for estimation of anti-oxidant and immune responses. Supplementation of Se, Cr and Zn increased (P  0.05) by the interaction between levels of Zn, Se and Cr in broiler diet. The FE improved (P  0.05) the immune responses (Newcastle disease titre and cell-mediated immune response to phytohaemagglutinin-P) in both the experiments. Based on the results, it is concluded that supplementation of organic form of Se, Cr and Zn (0.30, 2 and 40 mg/kg, respectively) either alone or in combination significantly improved performance and anti-oxidant responses (reduced LP and increased superoxide dismutase) in commercial

  14. Widespread Alu repeat-driven expansion of consensus DR2 retinoic acid response elements during primate evolution

    Directory of Open Access Journals (Sweden)

    Wang Tian-Tian

    2007-01-01

    Full Text Available Abstract Background Nuclear receptors are hormone-regulated transcription factors whose signaling controls numerous aspects of development and physiology. Many receptors recognize DNA hormone response elements formed by direct repeats of RGKTCA motifs separated by 1 to 5 bp (DR1-DR5. Although many known such response elements are conserved in the mouse and human genomes, it is unclear to which extent transcriptional regulation by nuclear receptors has evolved specifically in primates. Results We have mapped the positions of all consensus DR-type hormone response elements in the human genome, and found that DR2 motifs, recognized by retinoic acid receptors (RARs, are heavily overrepresented (108,582 elements. 90% of these are present in Alu repeats, which also contain lesser numbers of other consensus DRs, including 50% of consensus DR4 motifs. Few DR2s are in potentially mobile AluY elements and the vast majority are also present in chimp and macaque. 95.5% of Alu-DR2s are distributed throughout subclasses of AluS repeats, and arose largely through deamination of a methylated CpG dinucleotide in a non-consensus motif present in AluS sequences. We find that Alu-DR2 motifs are located adjacent to numerous known retinoic acid target genes, and show by chromatin immunoprecipitation assays in squamous carcinoma cells that several of these elements recruit RARs in vivo. These findings are supported by ChIP-on-chip data from retinoic acid-treated HL60 cells revealing RAR binding to several Alu-DR2 motifs. Conclusion These data provide strong support for the notion that Alu-mediated expansion of DR elements contributed to the evolution of gene regulation by RARs and other nuclear receptors in primates and humans.

  15. Glucose Enhances Basal or Melanocortin-Induced cAMP-Response Element Activity in Hypothalamic Cells.

    Science.gov (United States)

    Breit, Andreas; Wicht, Kristina; Boekhoff, Ingrid; Glas, Evi; Lauffer, Lisa; Mückter, Harald; Gudermann, Thomas

    2016-07-01

    Melanocyte-stimulating hormone (MSH)-induced activation of the cAMP-response element (CRE) via the CRE-binding protein in hypothalamic cells promotes expression of TRH and thereby restricts food intake and increases energy expenditure. Glucose also induces central anorexigenic effects by acting on hypothalamic neurons, but the underlying mechanisms are not completely understood. It has been proposed that glucose activates the CRE-binding protein-regulated transcriptional coactivator 2 (CRTC-2) in hypothalamic neurons by inhibition of AMP-activated protein kinases (AMPKs), but whether glucose directly affects hypothalamic CRE activity has not yet been shown. Hence, we dissected effects of glucose on basal and MSH-induced CRE activation in terms of kinetics, affinity, and desensitization in murine, hypothalamic mHypoA-2/10-CRE cells that stably express a CRE-dependent reporter gene construct. Physiologically relevant increases in extracellular glucose enhanced basal or MSH-induced CRE-dependent gene transcription, whereas prolonged elevated glucose concentrations reduced the sensitivity of mHypoA-2/10-CRE cells towards glucose. Glucose also induced CRCT-2 translocation into the nucleus and the AMPK activator metformin decreased basal and glucose-induced CRE activity, suggesting a role for AMPK/CRTC-2 in glucose-induced CRE activation. Accordingly, small interfering RNA-induced down-regulation of CRTC-2 expression decreased glucose-induced CRE-dependent reporter activation. Of note, glucose also induced expression of TRH, suggesting that glucose might affect the hypothalamic-pituitary-thyroid axis via the regulation of hypothalamic CRE activity. These findings significantly advance our knowledge about the impact of glucose on hypothalamic signaling and suggest that TRH release might account for the central anorexigenic effects of glucose and could represent a new molecular link between hyperglycaemia and thyroid dysfunction. PMID:27144291

  16. Glucose Enhances Basal or Melanocortin-Induced cAMP-Response Element Activity in Hypothalamic Cells.

    Science.gov (United States)

    Breit, Andreas; Wicht, Kristina; Boekhoff, Ingrid; Glas, Evi; Lauffer, Lisa; Mückter, Harald; Gudermann, Thomas

    2016-07-01

    Melanocyte-stimulating hormone (MSH)-induced activation of the cAMP-response element (CRE) via the CRE-binding protein in hypothalamic cells promotes expression of TRH and thereby restricts food intake and increases energy expenditure. Glucose also induces central anorexigenic effects by acting on hypothalamic neurons, but the underlying mechanisms are not completely understood. It has been proposed that glucose activates the CRE-binding protein-regulated transcriptional coactivator 2 (CRTC-2) in hypothalamic neurons by inhibition of AMP-activated protein kinases (AMPKs), but whether glucose directly affects hypothalamic CRE activity has not yet been shown. Hence, we dissected effects of glucose on basal and MSH-induced CRE activation in terms of kinetics, affinity, and desensitization in murine, hypothalamic mHypoA-2/10-CRE cells that stably express a CRE-dependent reporter gene construct. Physiologically relevant increases in extracellular glucose enhanced basal or MSH-induced CRE-dependent gene transcription, whereas prolonged elevated glucose concentrations reduced the sensitivity of mHypoA-2/10-CRE cells towards glucose. Glucose also induced CRCT-2 translocation into the nucleus and the AMPK activator metformin decreased basal and glucose-induced CRE activity, suggesting a role for AMPK/CRTC-2 in glucose-induced CRE activation. Accordingly, small interfering RNA-induced down-regulation of CRTC-2 expression decreased glucose-induced CRE-dependent reporter activation. Of note, glucose also induced expression of TRH, suggesting that glucose might affect the hypothalamic-pituitary-thyroid axis via the regulation of hypothalamic CRE activity. These findings significantly advance our knowledge about the impact of glucose on hypothalamic signaling and suggest that TRH release might account for the central anorexigenic effects of glucose and could represent a new molecular link between hyperglycaemia and thyroid dysfunction.

  17. HIV-1 p24(gag derived conserved element DNA vaccine increases the breadth of immune response in mice.

    Directory of Open Access Journals (Sweden)

    Viraj Kulkarni

    Full Text Available Viral diversity is considered a major impediment to the development of an effective HIV-1 vaccine. Despite this diversity, certain protein segments are nearly invariant across the known HIV-1 Group M sequences. We developed immunogens based on the highly conserved elements from the p24(gag region according to two principles: the immunogen must (i include strictly conserved elements of the virus that cannot mutate readily, and (ii exclude both HIV regions capable of mutating without limiting virus viability, and also immunodominant epitopes located in variable regions. We engineered two HIV-1 p24(gag DNA immunogens that express 7 highly Conserved Elements (CE of 12-24 amino acids in length and differ by only 1 amino acid in each CE ('toggle site', together covering >99% of the HIV-1 Group M sequences. Altering intracellular trafficking of the immunogens changed protein localization, stability, and also the nature of elicited immune responses. Immunization of C57BL/6 mice with p55(gag DNA induced poor, CD4(+ mediated cellular responses, to only 2 of the 7 CE; in contrast, vaccination with p24CE DNA induced cross-clade reactive, robust T cell responses to 4 of the 7 CE. The responses were multifunctional and composed of both CD4(+ and CD8(+ T cells with mature cytotoxic phenotype. These findings provide a method to increase immune response to universally conserved Gag epitopes, using the p24CE immunogen. p24CE DNA vaccination induced humoral immune responses similar in magnitude to those induced by p55(gag, which recognize the virus encoded p24(gag protein. The inclusion of DNA immunogens composed of conserved elements is a promising vaccine strategy to induce broader immunity by CD4(+ and CD8(+ T cells to additional regions of Gag compared to vaccination with p55(gag DNA, achieving maximal cross-clade reactive cellular and humoral responses.

  18. Melatonin and schistosomal antigens ameliorate the anti-oxidative and biochemical response to Schistosoma mansoni infection in hamster

    Institute of Scientific and Technical Information of China (English)

    Nahla S.El-SHENAWY; Maha F.M.SOLIMAN; Shimaa E.Abel-RAHMAN

    2009-01-01

    The present study was designed to investigate the potential protective effect of melatonin as an antioxidant separately or in combination with antigens (cercarial; CAP or soluble worm; SWAP) against Schistosoma mansoni infection in hamsters. Each hamster was sensitized with an initial immunization of 0.6 ml of the extracted antigen (30 μg protein/mL). After four days, a second injection of 0.4 mL was given (20 μg protein/mL). Then, each hamster was exposed to 260±20 S.mansoni cercariae followed with melatonin treatment (3.5 mg/kg) for thirty days from the 1st day of post infection. Levels of lipid peroxidation (LPO) products, catalase (CAT) activity, hepatic glutathione (GSH) and biochemical changes in the liver and kidneys functions were investigated. The results revealed a high significant increasing of LPO and decreasing of CAT and GSH in liver of infected hamsters. Biochemical observations showed severe damage in the liver enzyme activities and increasing cholesterol level in infected animals. Melatonin co-treatment with antigen to the infected-hamster attenuated the increase of LPO and restored the activity of CAT and levels of hepatic GSH. Also, the biochemical damages in the liver and kidneys functions were reduced. The present study suggests that melatonin may be useful in combating free radical-induced damage due to infection toxicity. The immunization with previous antigens resulted in a remarkable improvement on the liver enzyme activities, which were increased after infection. Thus, vaccination of hamsters with antigens (both CAP and SWAP) and melatonin treatment has more potent effect on the enhancement of antioxidant and biochemical of S.mansoni infected-hamster than each treatment separately. Immunization of the hamster with SWAP followed by melatonin was the best way among the other regime treatments to improve the biochemical and antioxidant parameters of the infected-hamsters[Current Zoology 55(2):165-172,2009].

  19. Antioxidant content in two CAM bromeliad species as a response to seasonal light changes in a tropical dry deciduous forest.

    Science.gov (United States)

    González-Salvatierra, Claudia; Luis Andrade, José; Escalante-Erosa, Fabiola; García-Sosa, Karlina; Manuel Peña-Rodríguez, Luis

    2010-07-01

    Plants have evolved photoprotective mechanisms to limit photodamage; one of these mechanisms involves the biosynthesis of antioxidant metabolites to neutralize reactive oxygen species generated when plants are exposed to excess light. However, it is known that exposure of plants to conditions of extreme water stress and high light intensity results in their enhanced susceptibility to over-excitation of photosystem II and to photooxidative stress. In this investigation we used the 2,2-diphenyl-1-picrylhydrazyl reduction assay to conduct a broad survey of the effect of water availability and light exposure conditions on the antioxidant activity of the leaf extracts of two bromeliad species showing crassulacean acid metabolism. One of these was an epiphyte, Tillandsia brachycaulos, and the other a terrestrial species, Bromelia karatas. Both species were found growing wild in the tropical dry deciduous forest of Dzibilchaltún National Park, México. The microenvironment of T. brachycaulos and B. karatas experiences significant diurnal and seasonal light variations as well as changes in temperature and water availability. The results obtained showed that, for both bromeliads, increases in antioxidant activity occurred during the dry season, as a consequence of water stress and higher light conditions. Additionally, in T. brachycaulos there was a clear correlation between high light intensity conditions and the content of anthocyanins which accumulated below the leaf epidermis. This result suggests that the role of these pigments is as photoprotective screens in the leaves. The red coloration below the leaf epidermis of B. karatas was not due to anthocyanins but to other unidentified pigments.

  20. Unraveling the mechanism responsible for the contrasting tolerance of Synechocystis and Synechococcus to Cr(VI): Enzymatic and non-enzymatic antioxidants

    International Nuclear Information System (INIS)

    Highlights: • Cr(VI) accumulation generates higher ROS in Synechocystis than in Synechococcus. • Synechococcus exhibits better photosynthetic activity in response to Cr(VI). • Synechococcus has higher enzymatic/non-enzymatic antioxidants than Synechocystis. • Synechococcus shows better tolerance to other oxidative stresses than Synechocystis. • Differential detoxification of ROS is responsible for the contrasting tolerance to Cr(VI) - Abstract: Two unicellular cyanobacteria, Synechocystis and Synechococcus, showed contrasting tolerance to Cr(VI); with Synechococcus being 12-fold more tolerant than Synechocystis to potassium dichromate. The mechanism responsible for this differential sensitivity to Cr(VI) was explored in this study. Total content of photosynthetic pigments as well as photosynthetic activity decreased at lower concentration of Cr(VI) in Synechocystis as compared to Synechococcus. Experiments with 51Cr showed Cr to accumulate intracellularly in both the cyanobacteria. At lower concentrations, Cr(VI) caused excessive ROS generation in Synechocystis as compared to that observed in Synechococcus. Intrinsic levels of enzymatic antioxidants, i.e., superoxide dismutase, catalase and 2-Cys-peroxiredoxin were considerably higher in Synechococcus than Synechocystis. Content of total thiols (both protein as well as non-protein) and reduced glutathione (GSH) was also higher in Synechococcus as compared to Synechocystis. This correlated well with higher content of carbonylated proteins observed in Synechocystis than Synechococcus. Additionally, in contrast to Synechocystis, Synechococcus exhibited better tolerance to other oxidative stresses like high intensity light and H2O2. The data indicate that the disparity in the ability to detoxify ROS could be the primary mechanism responsible for the differential tolerance of these cyanobacteria to Cr(VI)

  1. Unraveling the mechanism responsible for the contrasting tolerance of Synechocystis and Synechococcus to Cr(VI): Enzymatic and non-enzymatic antioxidants

    Energy Technology Data Exchange (ETDEWEB)

    Gupta, Alka [Molecular Biology Division, Bhabha Atomic Research Centre, Trombay, Mumbai 400085 (India); Ballal, Anand, E-mail: aballal@barc.gov.in [Molecular Biology Division, Bhabha Atomic Research Centre, Trombay, Mumbai 400085 (India); Homi Bhabha National Institute, Training School Complex, Anushakti Nagar, Mumbai 40085 (India)

    2015-07-15

    Highlights: • Cr(VI) accumulation generates higher ROS in Synechocystis than in Synechococcus. • Synechococcus exhibits better photosynthetic activity in response to Cr(VI). • Synechococcus has higher enzymatic/non-enzymatic antioxidants than Synechocystis. • Synechococcus shows better tolerance to other oxidative stresses than Synechocystis. • Differential detoxification of ROS is responsible for the contrasting tolerance to Cr(VI) - Abstract: Two unicellular cyanobacteria, Synechocystis and Synechococcus, showed contrasting tolerance to Cr(VI); with Synechococcus being 12-fold more tolerant than Synechocystis to potassium dichromate. The mechanism responsible for this differential sensitivity to Cr(VI) was explored in this study. Total content of photosynthetic pigments as well as photosynthetic activity decreased at lower concentration of Cr(VI) in Synechocystis as compared to Synechococcus. Experiments with {sup 51}Cr showed Cr to accumulate intracellularly in both the cyanobacteria. At lower concentrations, Cr(VI) caused excessive ROS generation in Synechocystis as compared to that observed in Synechococcus. Intrinsic levels of enzymatic antioxidants, i.e., superoxide dismutase, catalase and 2-Cys-peroxiredoxin were considerably higher in Synechococcus than Synechocystis. Content of total thiols (both protein as well as non-protein) and reduced glutathione (GSH) was also higher in Synechococcus as compared to Synechocystis. This correlated well with higher content of carbonylated proteins observed in Synechocystis than Synechococcus. Additionally, in contrast to Synechocystis, Synechococcus exhibited better tolerance to other oxidative stresses like high intensity light and H{sub 2}O{sub 2}. The data indicate that the disparity in the ability to detoxify ROS could be the primary mechanism responsible for the differential tolerance of these cyanobacteria to Cr(VI)

  2. Vegetable oils rich in alpha linolenic acid increment hepatic n-3 LCPUFA, modulating the fatty acid metabolism and antioxidant response in rats.

    Science.gov (United States)

    Rincón-Cervera, Miguel Ángel; Valenzuela, Rodrigo; Hernandez-Rodas, María Catalina; Barrera, Cynthia; Espinosa, Alejandra; Marambio, Macarena; Valenzuela, Alfonso

    2016-08-01

    Alpha-linolenic acid (C18:3 n-3, ALA) is an essential fatty acid and the metabolic precursor of long-chain polyunsaturated fatty acids (LCPUFA) from the n-3 family with relevant physiological and metabolic roles: eicosapentaenoic acid (C20:5 n-3, EPA) and docosahexaenoic acid (C22:6 n-3, DHA). Western diet lacks of suitable intake of n-3 LCPUFA and there are recommendations to increase the dietary supply of such nutrients. Seed oils rich in ALA such as those from rosa mosqueta (Rosa rubiginosa), sacha inchi (Plukenetia volubis) and chia (Salvia hispanica) may constitute an alternative that merits research. This study evaluated hepatic and epididymal accretion and biosynthesis of n-3 LCPUFA, the activity and expression of Δ-5 and Δ-6 desaturase enzymes, the expression and DNA-binding activity of PPAR-α and SREBP-1c, oxidative stress parameters and the activity of antioxidative enzymes in rats fed sunflower oil (SFO, 1% ALA) as control group, canola oil (CO, 10% ALA), rosa mosqueta oil (RMO, 33% ALA), sacha inchi oil (SIO, 49% ALA) and chia oil (ChO, 64% ALA) as single lipid source. A larger supply of ALA increased the accretion of n-3 LCPUFA, the activity and expression of desaturases, the antioxidative status, the expression and DNA-binding of PPAR-α, the oxidation of fatty acids and the activity of antioxidant enzymes, whereas the expression and DNA-binding activity of SREBP-1c transcription factor and the biosynthetic activity of fatty acids declined. Results showed that oils rich in ALA such as SIO and ChO may trigger metabolic responses in rats such as those produced by n-3 PUFA. PMID:26995676

  3. Involvement of MEK-ERK1-2 pathway in the anti-oxidant response in C6 glioma cells after diesel exhaust particles exposure.

    Science.gov (United States)

    Farina, Francesca; Milani, Chiara; Botto, Laura; Lonati, Elena; Bulbarelli, Alessandra; Palestini, Paola

    2016-05-27

    Ultrafine particles translocate to the central nervous system and activate oxidative stress-related pathways. The transcription factor Nrf2 activation by ERK1-2 has been suggested as a key regulator of cellular response to oxidative stress. C6 glioma cells have been treated with different doses of diesel exhaust particles (25μg/ml, DEP25, and 50μg/ml, DEP50), for different times. Cells have been screened for oxidative stress and inflammatory markers, and for the activation of the MEK-ERK1-2 pathway. The same markers have been examined after inhibition of MEK, the kinase upstream to ERK1-2. 3h and 24h of DEP25 and DEP50 induced a significant increase in HO-1 levels. After 24h, DEP25 and DEP50 induced an increase in HO-1 and Cyp1b1 levels, while increase in OGG1 level was observed only with DEP25. After 5h of treatment with DEP25, ERK1-2 resulted phosphorylated, concomitantly with a significant increase in HO-1 levels, no changes in iNOS levels, and decreased levels of anti-oxidant enzymes. After treatment with MEK inhibitor U0126, ERK1-2 showed no activation, with a consequent decrease in Nrf2, no increase in HO-1 and a significant increase of iNOS. MEK inhibitor is able to deplete anti-oxidant enzymes. In conclusion, the MEK-ERK1-2 pathway is involved in regulating the anti-oxidant strategies to compensate the oxidative status induced by DEP treatment. PMID:27091075

  4. Vegetable oils rich in alpha linolenic acid increment hepatic n-3 LCPUFA, modulating the fatty acid metabolism and antioxidant response in rats.

    Science.gov (United States)

    Rincón-Cervera, Miguel Ángel; Valenzuela, Rodrigo; Hernandez-Rodas, María Catalina; Barrera, Cynthia; Espinosa, Alejandra; Marambio, Macarena; Valenzuela, Alfonso

    2016-08-01

    Alpha-linolenic acid (C18:3 n-3, ALA) is an essential fatty acid and the metabolic precursor of long-chain polyunsaturated fatty acids (LCPUFA) from the n-3 family with relevant physiological and metabolic roles: eicosapentaenoic acid (C20:5 n-3, EPA) and docosahexaenoic acid (C22:6 n-3, DHA). Western diet lacks of suitable intake of n-3 LCPUFA and there are recommendations to increase the dietary supply of such nutrients. Seed oils rich in ALA such as those from rosa mosqueta (Rosa rubiginosa), sacha inchi (Plukenetia volubis) and chia (Salvia hispanica) may constitute an alternative that merits research. This study evaluated hepatic and epididymal accretion and biosynthesis of n-3 LCPUFA, the activity and expression of Δ-5 and Δ-6 desaturase enzymes, the expression and DNA-binding activity of PPAR-α and SREBP-1c, oxidative stress parameters and the activity of antioxidative enzymes in rats fed sunflower oil (SFO, 1% ALA) as control group, canola oil (CO, 10% ALA), rosa mosqueta oil (RMO, 33% ALA), sacha inchi oil (SIO, 49% ALA) and chia oil (ChO, 64% ALA) as single lipid source. A larger supply of ALA increased the accretion of n-3 LCPUFA, the activity and expression of desaturases, the antioxidative status, the expression and DNA-binding of PPAR-α, the oxidation of fatty acids and the activity of antioxidant enzymes, whereas the expression and DNA-binding activity of SREBP-1c transcription factor and the biosynthetic activity of fatty acids declined. Results showed that oils rich in ALA such as SIO and ChO may trigger metabolic responses in rats such as those produced by n-3 PUFA.

  5. Feasibility of using neural networks to unfold the response of multi-element TLD for mixed field dosimetry

    International Nuclear Information System (INIS)

    Significant advances have been made in recent years to improve calibration methodology and dose calculation algorithm in the fields of TL dosimetry. This process was accelerated in the past decade particularly in the Republic of Korea by the need to meet mandatory national accreditation requirements. The objective of this study is to develop a new algorithm to replace the simplistic decision tree algorithms by the more sophisticated neural networks in hopes of achieving a higher degree of accuracy and precision in personnel dosimetry system. The original hypothesis of this work is that the spectral information of an X and γ-ray fields may be obtained by the analysis of the response of a multi-element system. In this study, a feed forward neural network using the error back-propagation method with Bayesian optimization was designed for the response unfolding procedure. The response functions of the single element to photons were calculated by application of a computational Monte-Carlo model for an energy range from 10 keV to 2 MeV with different spectral proportions. The training of the artificial neural network was based on the computation of responses of a four-element system for the back-propagation method. The validation of the proposed algorithm was investigated by unfolding the 10 computed responses for arbitrary mixed gamma fields and the spectra resulting from the unfolding procedure agree well with the original spectra. (author)

  6. Optimization of Ultrasound-Assisted Extraction of Natural Antioxidants from Sugar Apple (Annona squamosa L. Peel Using Response Surface Methodology

    Directory of Open Access Journals (Sweden)

    Gui-Fang Deng

    2015-11-01

    Full Text Available Sugar apple (Annona squamosa L. is a popular tropical fruit and its peel is a municipal waste. An ultrasound-assisted extraction method was developed for the recovery of natural antioxidants from sugar apple peel. Central composite design was used to optimize solvent concentration (13.2%–46.8%, ultrasonic time (33.2–66.8 min, and temperature (43.2–76.8 °C for the recovery of natural antioxidants from sugar apple peel. The second-order polynomial models demonstrated a good fit of the quadratic models with the experimental results in respect to total phenolic content (TPC, R2 = 0.9524, p < 0.0001, FRAP (R2 = 0.9743, p < 0.0001, and TEAC (R2 = 0.9610, p < 0.0001 values. The optimal extraction conditions were 20:1 (mL/g of solvent-to-solid ratio, 32.68% acetone, and 67.23 °C for 42.54 min under ultrasonic irradiation. Under these conditions, the maximal yield of total phenolic content was 26.81 (mg GA/g FW. The experimental results obtained under optimal conditions agreed well with the predicted results. The application of ultrasound markedly decreased extraction time and improved the extraction efficiency, compared with the conventional methods.

  7. Response of antioxidant defense system in copepodCalanus sinicus Brodsky exposed to CO2-acidified seawater

    Institute of Scientific and Technical Information of China (English)

    ZHANG Dajuan; GUO Donghui; WANG Guizhong; LI Shaojing

    2016-01-01

    Marine zooplankton responds sensitively to elevated seawater CO2 concentration. However, the underlying physiological mechanisms have not been studied well. We therefore investigated the effects of elevated CO2 concentration (0.08%, 0.20%, 0.50% and 1.00%) on antioxidant defense components, as well as two detoxification enzymes ofCalanus sinicus (copepod). The results showed that glutathione peroxidase (GPx) activity exposed to CO2-acidified seawater was significantly stimulated while other antioxidant components, including glutathione-S-transferase (GST) activity, superoxide dismutase (SOD) activity decreased significantly with reduced glutathione (GSH) level and GSH/oxidized glutathione (GSSG) value. CO2-acidified seawater exhibited stimulatory effects on adenosine triphosphatase (ATPase) activity and acetylcholinesterase (AchE) activity was inhibited. Moreover, the results of principal component analysis indicated that 75.93% of the overall variance was explained by the first two principal components. The elevated CO2 concentration may affect the metabolism and survivals of copepods through impacts these enzymes activities. Further studies are needed to focus on the synergistic effects of elevated CO2 concentration and other environmental factors on copepods.

  8. Phenolic content, antioxidant and astroprotective response to oxidative stress of ethanolic extracts of Mentha longifolia from Sinai.

    Science.gov (United States)

    Eissa, Tarek F; González-Burgos, Elena; Carretero, M Emilia; Gómez-Serranillos, M Pilar

    2014-10-01

    The aerial parts ofMentha longifolia L. are used as herbal remedies for curing different diseases through traditional Bedouin medicine. The antioxidant activity of the ethanolic extracts of M longifolia was investigated measuring peroxyl radical-scavenging activity by ORAC assay, with Trolox (a water-soluble analogue of α-tocopherol) employed as reference compound. In addition, the total content of phenolic compounds estimated by the Folin-Ciocalteau method and the identification of the polyphenols using high-performance liquid chromatography coupled with mass spectrometry (HPLC-MS) have been performed. Furthermore, the effect of these extracts on cell viability and intracellular ROS production was assayed using the U373-MG human astrocytoma cell line in a H2O2-induced oxidative stress model. Results showed that the major type of polyphenols found were benzoic acids, cinnamic acids, flavones and flavanones. The total phenolic content was 37.7 mg gallic acid/g sample and the ORAC value was 1.355 .mol TE/mg sample. The data obtained in cellular assays demonstrated that these ethanolic extracts protected H2O2-induced astrocyte damage by increasing cell viability and inhibiting production of intracellular ROS. These results suggest that the investigated extracts obtained from the aerial parts of M longifolia have antioxidant potential related to their phenol content which have important beneficial health effects, especially in those disease associated with ROS.

  9. The characterization of two peroxiredoxin genes in Dunaliella viridis provides insights into antioxidative response to salt stress.

    Science.gov (United States)

    Yuan, Huijuan; Meng, Xiangzong; Gao, Qiang; Qu, Wufei; Xu, Tengjiao; Xu, Zhengkai; Song, Rentao

    2011-08-01

    Peroxiredoxins (Prxs), a group of antioxidant enzymes, are an important component of the oxidative defense system and have been demonstrated to function as peroxidases, sensors of H(2)O(2)-mediated signaling and/or chaperones. In this study, a cDNA library was constructed from a halotolerant alga, Dunaliella viridis, and was used in a functional complementation screen for antioxidative genes in an oxidative sensitive yeast mutant. Two Prx genes, DvPrx1 and DvPrx2, were obtained from this screen. These two genes were classified as type II Prx and 2-Cys Prx based on amino acid sequence and phylogenetic analysis. When over-expressed in yeast cells, both Prx genes were able to confer better oxidative tolerance and decrease the level of reactive oxygen species (ROS). Subcellular localization experiments in tobacco cells revealed that both DvPrx1 and DvPrx2 were localized in the cytosol. The transcription of DvPrx1 and DvPrx2 can be induced by hypersalinity shock, but is not obviously affected by treatment with high levels of oxidant. Our results shed light on the function and regulation of Prx genes from Dunaliella and their potential roles in salt tolerance. PMID:21431909

  10. RelA is a potent transcriptional activator of the CD28 response element within the interleukin 2 promoter.

    OpenAIRE

    Lai, J. H.; HORVATH, G; Subleski, J; Bruder, J.; P. Ghosh; Tan, T H

    1995-01-01

    T-cell activation requires two different signals. The T-cell receptor's recognition of a specific antigen on antigen-presenting cells provides one, and the second signal comes from costimulatory molecules such as CD28. In contrast, T cells that are stimulated with antigen in the absence of the CD28 costimulatory signal can become anergic (nonresponsive). The CD28 response element (CD28RE) has been identified as the DNA element mediating interleukin 2 (IL-2) gene activation by CD28 costimulati...

  11. Alterations in oxidant/antioxidant balance, high-mobility group box 1 protein and acute phase response in cross-bred suckling piglets suffering from rotaviral enteritis.

    Science.gov (United States)

    Kumar De, Ujjwal; Mukherjee, Reena; Nandi, Sukdeb; Patel, Bhimnere Hanumatnagouda Manjunatha; Dimri, Umesh; Ravishankar, Chintu; Verma, Ashok Kumar

    2014-10-01

    Rotaviral enteritis has emerged as a major cause of morbidity and mortality in piglets during their post-natal life. The present study was carried out to examine high-mobility group box 1 (HMGB1) protein, acute phase response and oxidative stress indices in the serum of suckling piglets suffering from enteritis with or without association of porcine group A rotavirus infection. The present investigation utilized 23 clinical cases with signs of acute enteritis and 12 more healthy piglets of a similar age group as control animals. Out of 23 enteritis cases, 12 cases were found to be positive for porcine group A rotavirus infection as confirmed by reverse transcription-polymerase chain reaction (RT-PCR) using specific primers for group A rotavirus, and the rest were found negative. The acute enteritis cases in piglets were associated with an elevated level of HMGB1 protein and serum haptoglobin and ceruloplasmin suggestive of an acute phase response. Among the oxidative stress indices, the concentrations of malondialdehyde (MDA) and nitric oxide (NO) in serum were significantly increased. A pronounced drop of total antioxidant capacity and the activity of antioxidant enzymes such as catalase and superoxide dismutase in the serum of piglets suffering from acute enteritis compared to healthy ones were also noticed. The alterations in HMGB1 protein, acute phase response and oxidative stress indices were more pronounced in cases with the involvement of porcine rotavirus as compared to rotavirus-negative cases. It is concluded that HMGB1 protein, markers of oxidative stress and acute phase proteins might play an important role in the aetiopathogenesis of porcine diarrhoea caused by rotavirus and might be true markers in diagnosing the conditions leading to the extension of the prompt and effective therapeutic care.

  12. Elucidation of lead-induced oxidative stress in Talinum triangulare roots by analysis of antioxidant responses and DNA damage at cellular level.

    Science.gov (United States)

    Kumar, Abhay; Prasad, M N V; Mohan Murali Achary, V; Panda, Brahma B

    2013-07-01

    Hydroponic experiments were performed with Talinum triangulare (Jacq.) Willd. focusing the root cellular biochemistry with special emphasis on DNA damage, structural, and elemental analyses in Pb(NO3)2 exposed with 0, 0.25, 0.5, 0.75, 1.0, and 1.25 mM for 7 days. Lead (Pb) increased reactive oxygen species production, lipid peroxidation, protein oxidation, cell death, and DNA damage and decreased the protein content in a dose-dependent manner. Likewise, a dose-dependent induction of antioxidative enzymes superoxide dismutase and catalase by Pb was evident. Ascorbate peroxidase on the other hand responded biphasically to Pb treatments by showing induction at low (0.25 and 0.50) and repression at high (0.75-1.25 mM) concentrations. The estimation of proline content also indicated a similar biphasic trend. Scanning electron microscope and energy-dispersive X-ray spectroscopy analysis showed that 1.25 mM Pb treatment resulted in ultrastructural modifications in roots and stem tissue that was marked by the change in the elemental profile. The findings pointed to the role of oxidative stress in the underlying Pb phytotoxicity and genotoxicity in T. triangulare. PMID:23263755

  13. Tamarind seed coat extract restores reactive oxygen species through attenuation of glutathione level and antioxidant enzyme expression in human skin fibroblasts in response to oxidative stress

    Directory of Open Access Journals (Sweden)

    Oranuch Nakchat

    2014-05-01

    Conclusions: TSCE exhibited antioxidant activities by scavenging ROS, attenuating GSH level that could protect human skin fibroblast cells from oxidative stress. Our results highlight the antioxidant mechanism of tamarind seed coat through an antioxidant enzyme system, the extract potentially benefits for health food and cosmeceutical application of tamarind seed coat.

  14. The Nrf2 System as a Potential Target for the Development of Indirect Antioxidants

    Directory of Open Access Journals (Sweden)

    Mi-Kyoung Kwak

    2010-10-01

    Full Text Available Oxidative stress causes damage to multiple cellular components such as DNA, proteins, and lipids, and is implicated in various human diseases including cancer, neurodegeneration, inflammatory diseases, and aging. In response to oxidative attack, cells have developed an antioxidant defense system to maintain cellular redox homeostasis and to protect cells from damage. The thiol-containing small molecules (e.g. glutathione, reactive oxygen species-inactivating enzymes (e.g. glutathione peroxidase, and phase 2 detoxifying enzymes (e.g. NAD(PH: quinine oxidoreductase 1 and glutathione-S-transferases are members of this antioxidant system. NF-E2-related factor 2 (Nrf2 is a CNC-bZIP transcription factor which regulates the basal and inducible expression of a wide array of antioxidant genes. Following dissociation from the cytosolic protein Keap1, a scaffolding protein which binds Nrf2 and Cul3 ubiquitin ligase for proteasome degradation, Nrf2 rapidly accumulates in the nucleus and transactivates the antioxidant response element in the promoter region of many antioxidant genes. The critical role of Nrf2 has been demonstrated by various animal studies showing that mice with a targeted disruption of the nrf2 gene are prone to develop lesions in response to environmental toxicants/carcinogens, drugs, and inflammatory insults. In this review, we discuss the role of the Nrf2 system, with particular focus on Nrf2-controlled target genes and the potential pleiotropic effects of Nrf2 activation of indirect antioxidants.

  15. Initial response and subsequent course of Crohn's disease treated with elemental diet or prednisolone.

    Science.gov (United States)

    Gorard, D A; Hunt, J B; Payne-James, J J; Palmer, K R; Rees, R G; Clark, M L; Farthing, M J; Misiewicz, J J; Silk, D B

    1993-09-01

    Elemental diet is as effective as corticosteroids in the treatment of previously untreated Crohn's disease. It is unclear whether a poor nutritional state is a prerequisite for efficacy of elemental diet, whether previously treated patients respond as well, or how duration of remission using elemental diet compares with corticosteroid induced remission. Forty two patients with active Crohn's disease were stratified for nutritional state and randomised to receive Vivonex TEN 2.1 l/day for four weeks, or 0.75 mg prednisolone/kg/day for two weeks and subsequent reducing doses. Nine of 22 (41%) patients assigned to nutritional treatment were intolerant of the diet. Thirty patients completed four weeks treatment. Disease activity decreased on elemental diet from mean (SEM) 4.8 (0.9) to 1.7 (0.6), p < 0.05, and on prednisolone from 5.3 (0.5) to 1.9 (0.6), p < 0.05. For each treatment, nourished and malnourished patients responded similarly. Patients with longstanding disease responded as well as newly diagnosed patients. The probability of maintaining remission at six months was 0.67 after prednisolone, 0.28 after elemental diet, and at one year was 0.35 after prednisolone and 0.09 after elemental diet, p < 0.05. When tolerated, elemental diet is as effective in the short term as prednisolone in newly and previously diagnosed Crohn's disease, and its benefit is independent of nutritional state. The subsequent relapse rate after elemental diet induced remission, however, is greater than after treatment with prednisolone. PMID:8406153

  16. Modeling and assessment of the response of super-light elements to fire

    DEFF Research Database (Denmark)

    Hertz, Kristian Dahl; Campeanu, B.M.; Giraudo, M.;

    2013-01-01

    . The implementation of a three-dimensional Finite Element Model (FEM) of the SL-deck is described and modelling aspects are discussed with particular reference to the sensitivity of the model to the thermal properties of the strong and light concrete. The results of the investigation are compared with the outcomes...... of the fire performances of complex concrete elements and in the focus on modelling issues related to the handling of the uncertainties. © 2013 Taylor & Francis Group....

  17. Modeling and assessment of the response of super-light elements to fire

    DEFF Research Database (Denmark)

    Hertz, Kristian Dahl; Campeanu, B.M.; Giraudo, M.;

    . The implementation of a three-dimensional finite element model (FEM) of the SL-deck is described and modelling aspects are discussed with particular reference to the sensitivity of the model to the thermal properties of the strong and light concrete. The results of the investigation are compared with the outcomes...... of the fire performances of complex concrete elements and in the focus on modelling issues related to the handling of the uncertainties....

  18. Antioxidant responses to benzo[a]pyrene,tributyltin and their mixture in the spleen of Sebasticus marmoratus

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    It has been repotted that there is an interaction between Benzo[a]pyrene (BaP),a widespread carcinogenic polycyclic aromatic hydrocarbon,and tributyltin (TBT),an organometal used as an antifouling biocide.This study was therefore designed to examine the potential in vivo influence of BaP,TBT and their mixture on splenic antioxidant defense systems of Sebastiscus marmoratus.The fish were exposed to water containing euvironmentally relevant concentrations of BaP,TBT and their mixture.Spleens were collected for biochemical analysis after exposure for 7,25,50 d and after recovery for 7,20 d.Cotreatment with BaP and TBT for 7 d potentiated the induction of glutathione pemxidase (GPx) activity by BaP or TBT alone.The cotreatment for 25 and 50 d resulted in inhibition of GPx activity,which was similar to the effect of TBT.Splenic glutathione S-transferase (GST) activities were significantly elevated in S.marmoratus exposed to BaP starting from 7d and remained high up to 25 d.However,no further activity change was found with prolonged exposure.Cotreatment of BaP and TBT primarily inhibited the GST activity,which was similar to the effect of TBT.Cotreatment with BaP and TBT for 25 or 50 d potentiated the depletion of GSH (glutathione) by BaP or TBT alone.MDA (malondialdehyde) contents in spleen of S.marmoratus were not significantly altered compared with the control during the test period.Spleen,as an immune organ,is sensitive to exposure of BaP or TBT.It should have an effective mechanism to counteract oxidative damage.Antioxidative defense systems in spleen of S.marmoratus should be considered as potential biomarkers.Short-term exposure of BaP or TBT could result in induction of antioxidant defense system.A significant decrease of these indices.such as GSH,GST,GPx might indicate more severe contamination.

  19. Finite element model validation of bridge based on structural health monitoring—Part I: Response surface-based finite element model updating

    Directory of Open Access Journals (Sweden)

    Zhouhong Zong

    2015-08-01

    Full Text Available In the engineering practice, merging statistical analysis into structural evaluation and assessment is a tendency in the future. As a combination of mathematical and statistical techniques, response surface (RS methodology has been successfully applied to design optimization, response prediction and model validation. With the aid of RS methodology, these two serial papers present a finite element (FE model updating and validation method for bridge structures based on structural health monitoring. The key issues to implement such a model updating are discussed in this paper, such as design of experiment, parameter screening, construction of high-order polynomial response surface model, optimization methods and precision inspection of RS model. The proposed procedure is illustrated by a prestressed concrete continuous rigid-frame bridge monitored under operational conditions. The results from the updated FE model have been compared with those obtained from online health monitoring system. The real application to a full-size bridge has demonstrated that the FE model updating process is efficient and convenient. The updated FE model can relatively reflect the actual condition of Xiabaishi Bridge in the design space of parameters and can be further applied to FE model validation and damage identification.

  20. Atranorin and lecanoric acid antagonize TCDD-induced xenobiotic response element-driven activity, but not xenobiotic response element-independent activity.

    Science.gov (United States)

    Nakashima, Ken-Ichi; Tanabe, Hiroki; Fujii-Kuriyama, Yoshiaki; Hayashi, Hidetoshi; Inoue, Makoto

    2016-07-01

    Lichens are symbiotic organisms that consist of fungi and photosynthetic symbionts (algae and/or cyanobacteria). Previous studies of their constituents suggested lichens produce many kinds of aromatic secondary metabolites, such as depsides, quinones, and dibenzofurans. In this study, we evaluated the aryl hydrocarbon receptor (AhR) antagonistic activity of 17 lichen substances and demonstrated that atranorin (1) and lecanoric acid (2), isolated from Parmotrema tinctorum Hale, showed an inhibitory effect on luciferase activity increased by 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD), using an XRE-driven pX4TK-Luc reporter gene assay. In addition, CYP1A1 mRNA and protein levels increased by TCDD were also suppressed by 1 and 2. Conversely, neither 1 nor 2 antagonized the suppressive effect of TCDD on interleukin (IL)-1β-induced acute-phase response (APR) gene expression. Thus, we concluded that 1 and 2 were selective AhR modulators that antagonize XRE-dependent activity, but not XRE-independent activity. However, 1 has different characteristics to 2 in that 1 alone showed a suppressive effect on IL-1β-induced APR gene expression in a similar fashion to TCDD. PMID:26979434

  1. Nutritional Status as the Key Modulator of Antioxidant Responses Induced by High Environmental Ammonia and Salinity Stress in European Sea Bass (Dicentrarchus labrax.

    Directory of Open Access Journals (Sweden)

    Amit Kumar Sinha

    Full Text Available Salinity fluctuation is one of the main factors affecting the overall fitness of marine fish. In addition, water borne ammonia may occur simultaneously with salinity stress. Additionally, under such stressful circumstances, fish may encounter food deprivation. The physiological and ion-osmo regulatory adaptive capacities to cope with all these stressors alone or in combination are extensively addressed in fish. To date, studies revealing the modulation of antioxidant potential as compensatory response to multiple stressors are rather lacking. Therefore, the present work evaluated the individual and combined effects of salinity challenge, ammonia toxicity and nutritional status on oxidative stress and antioxidant status in a marine teleost, European sea bass (Dicentrarchus labrax. Fish were acclimated to normal seawater (32 ppt, to brackish water (20 ppt and 10 ppt and to hypo-saline water (2.5 ppt. Following acclimation to different salinities for two weeks, fish were exposed to high environmental ammonia (HEA, 20 mg/L representing 50% of 96h LC50 value for ammonia for 12 h, 48 h, 84 h and 180 h, and were either fed (2% body weight or fasted (unfed for 7 days prior to HEA exposure. Results show that in response to decreasing salinities, oxidative stress indices such as xanthine oxidase activity, levels of hydrogen peroxide (H2O2 and lipid peroxidation (malondialdehyde, MDA increased in the hepatic tissue of fasted fish but remained unaffected in fed fish. HEA exposure at normal salinity (32 ppt and at reduced salinities (20 ppt and 10 ppt increased ammonia accumulation significantly (84 h-180 h in both feeding regimes which was associated with an increment of H2O2 and MDA contents. Unlike in fasted fish, H2O2 and MDA levels in fed fish were restored to control levels (84 h-180 h; with a concomitant increase in superoxide dismutase (SOD, catalase (CAT, components of the glutathione redox cycle (reduced glutathione, glutathione peroxidase and

  2. Effect of aluminium toxicity on growth responses and antioxidant activities in Gmelina arborea Roxb. inoculated with AM fungi.

    Science.gov (United States)

    Dudhane, Mayura; Borde, Mahesh; Jite, Paramjit Kaur

    2012-08-01

    Arbuscular mycorrhizal fungi alleviating the adverse Aluminium effects on growth and antioxidant activity was tested in Gmelina plants. Under greenhouse and aluminium stress condition, the mycorrhizal Gmelina plants showed good growth as compared to non mycorrhizal Gmelina plants. Mycorrhizal colonization in Gmelina was found not to be significantly influenced by aluminium concentrations. Results also indicate that symbiotic association was successfully established between Glomus intraradices and Gmelina plants and mycorrhizal colonization consequently increased the biomass of Gmelina. The root proline accumulation was found to increase in mycorrhizal Gmelina plants for osmotic adjustment of stress tissues under first and second level of Aluminium stress. It was observed that Mycorrhizal colonization increased the shoot root Peroxidase and Superoxide dismutase activities in mycorrhizal Gmelina under second level of Aluminium stress. Mycorrhizal fungi play a major role in phytostabilization by secreting one of the glycoprotein, i.e., Glomalin, which stabilizes the Aluminium in soil as well as in the roots of Gmelina plants. PMID:22908633

  3. SANTOS - a two-dimensional finite element program for the quasistatic, large deformation, inelastic response of solids

    Energy Technology Data Exchange (ETDEWEB)

    Stone, C.M.

    1997-07-01

    SANTOS is a finite element program designed to compute the quasistatic, large deformation, inelastic response of two-dimensional planar or axisymmetric solids. The code is derived from the transient dynamic code PRONTO 2D. The solution strategy used to compute the equilibrium states is based on a self-adaptive dynamic relaxation solution scheme, which is based on explicit central difference pseudo-time integration and artificial mass proportional damping. The element used in SANTOS is a uniform strain 4-node quadrilateral element with an hourglass control scheme to control the spurious deformation modes. Finite strain constitutive models for many common engineering materials are included. A robust master-slave contact algorithm for modeling sliding contact is implemented. An interface for coupling to an external code is also provided. 43 refs., 22 figs.

  4. First-principles study on the effect of alloying elements on the elastic deformation response in β-titanium alloys

    Energy Technology Data Exchange (ETDEWEB)

    Gouda, Mohammed K., E-mail: mohamed.kamal@ejust.edu.eg; Gepreel, Mohamed A. H. [Materials Science and Engineering Department, Egypt-Japan University of Science and Technology, Borg El Arab, Alexandria 21934 (Egypt); Nakamura, Koichi [Materials Science and Engineering Department, Egypt-Japan University of Science and Technology, Borg El Arab, Alexandria 21934 (Egypt); Center for the Promotion of Interdisciplinary Education and Research, Kyoto University, Kyoto 615-8540 (Japan)

    2015-06-07

    Theoretical deformation response of hypothetical β-titanium alloys was investigated using first-principles calculation technique under periodic boundary conditions. Simulation was carried out on hypothetical 54-atom supercell of Ti–X (X = Cr, Mn, Fe, Zr, Nb, Mo, Al, and Sn) binary alloys. The results showed that the strength of Ti increases by alloying, except for Cr. The most effective alloying elements are Nb, Zr, and Mo in the current simulation. The mechanism of bond breaking was revealed by studying the local structure around the alloying element atom with respect to volume change. Moreover, the effect of alloying elements on bulk modulus and admissible strain was investigated. It was found that Zr, Nb, and Mo have a significant effect to enhance the admissible strain of Ti without change in bulk modulus.

  5. Acupuncture ameliorates cognitive impairment and hippocampus neuronal loss in experimental vascular dementia through Nrf2-mediated antioxidant response.

    Science.gov (United States)

    Wang, Xue-Rui; Shi, Guang-Xia; Yang, Jing-Wen; Yan, Chao-Qun; Lin, Li-Ting; Du, Si-Qi; Zhu, Wen; He, Tian; Zeng, Xiang-Hong; Xu, Qian; Liu, Cun-Zhi

    2015-12-01

    Emerging evidence suggests acupuncture could exert neuroprotection in the vascular dementia via anti-oxidative effects. However, the involvement of Nrf2, a master regulator of antioxidant defense, in acupuncture-induced neuroprotection in vascular dementia remains undetermined. The goal of our study was to investigate the contribution of Nrf2 in acupuncture and its effects on vascular dementia. Morris water maze and Nissl staining were used to assess the effect of acupuncture on cognitive function and hippocampal neurodegeneration in experimental vascular dementia. The distribution of Nrf2 in neurons in hippocampus, the protein expression of Nrf2 in both cytosol and nucleus, and the protein and mRNA levels of its downstream target genes NQO1 and HO-1 were detected by double immunofluorescent staining, Western blotting and realtime PCR analysis respectively. Cognitive function and microglia activation were measured in both wild-type and Nrf2 gene knockout mice after acupuncture treatment. We found that acupuncture could remarkably reverse the cognitive deficits, neuron cell loss, reactive oxygen species production, and decreased cerebral blood flow. It was notable that acupuncture enhanced nuclear translocation of Nrf2 in neurons and up-regulate the protein and mRNA levels of Nrf2 and its target genes HO-1 and NQO1. Moreover, acupuncture could significantly down-regulated the over-activation of microglia after common carotid artery occlusion surgery. However, the reversed cognitive deficits, neuron cell loss and microglia activation by acupuncture were abolished in Nrf2 gene knockout mice. In conclusion, these findings provide evidence that the neuroprotection of acupuncture in models of vascular dementia was via the Nrf2 activation and Nrf2-dependent microglia activation. PMID:26546103

  6. Process Optimization of Ultrasonic-Assisted Extraction of Arabinogalactan from Dihydroquercetin Extracted Residues by Response Surface Methodology and Evaluation of Its Antioxidant Activity

    Directory of Open Access Journals (Sweden)

    Zaizhi Liu

    2013-01-01

    Full Text Available Ultrasound was used for the extraction of larch arabinogalactan from Larix gmelinii. The optimal conditions for ultrasound extraction were determined by response surface methodology. Specifically, the Box-Behnken design was employed to evaluate the effects of three independent variables: ultrasound time, temperature, and liquid-solid ratio. The highest arabinogalactan yield (11.18% was obtained under the optimal extraction condition (extraction temperature 41.5°C, extraction time 24.3 min, and liquid-solid ratio 40 mL/g. In addition, the antioxidant activity of arabinogalactan that was extracted from dihydroquercetin extraction residues exhibited a moderate and concentration-dependent hydroxyl radical-scavenging capacity, ferric-reducing power, and reducing power. The wood material was characterized before and after processing by scanning electron microscopy and Fourier-transform infrared spectroscopy.

  7. Responses of Nigella sativa L. to Zinc Excess: Focus on Germination, Growth, Yield and Yield Components, Lipid and Terpene Metabolism, and Total Phenolics and Antioxidant Activities.

    Science.gov (United States)

    Marichali, Ahmed; Dallali, Sana; Ouerghemmi, Saloua; Sebei, Houcine; Casabianca, Hervé; Hosni, Karim

    2016-03-01

    A comprehensive analysis of the responses of Nigella sativa L. to elevated zinc concentrations was assessed in pot experiments. Zn excess supply did not affect the germination but drastically reduced radicle elongation. A concentration-dependent reduction in all growth parameters, yield, and yield components was observed. With the increasing Zn concentrations, total lipid contents decreased and changes in fatty composition toward the production of saturated ones were underscored. Despite the reduction in the seeds essential oil yield, a redirection of the terpene metabolism toward the synthesis of oxygenated compounds has been evidenced. A significant increase in the total phenols and flavonoids contents concomitant with improved antioxidant activities has also been found. Collectively, these results highlight the possible use of N. sativa L. in phytoremediation applications, on the one hand, and that Zn excess could represent an excellent alternative to improve the nutritional attributes of this important species, on the other hand. PMID:26853463

  8. Temperature, stress, and corrosive sensing apparatus utilizing harmonic response of magnetically soft sensor element (s)

    Science.gov (United States)

    Grimes, Craig A. (Inventor); Ong, Keat Ghee (Inventor)

    2003-01-01

    A temperature sensing apparatus including a sensor element made of a magnetically soft material operatively arranged within a first and second time-varying interrogation magnetic field, the first time-varying magnetic field being generated at a frequency higher than that for the second magnetic field. A receiver, remote from the sensor element, is engaged to measure intensity of electromagnetic emissions from the sensor element to identify a relative maximum amplitude value for each of a plurality of higher-order harmonic frequency amplitudes so measured. A unit then determines a value for temperature (or other parameter of interst) using the relative maximum harmonic amplitude values identified. In other aspects of the invention, the focus is on an apparatus and technique for determining a value for of stress condition of a solid analyte and for determining a value for corrosion, using the relative maximum harmonic amplitude values identified. A magnetically hard element supporting a biasing field adjacent the magnetically soft sensor element can be included.

  9. Fingerprinting antioxidative activities in plants

    Directory of Open Access Journals (Sweden)

    Plieth Christoph

    2009-01-01

    Full Text Available Abstract Background A plethora of concurrent cellular activities is mobilised in the adaptation of plants to adverse environmental conditions. This response can be quantified by physiological experiments or metabolic profiling. The intention of this work is to reduce the number of metabolic processes studied to a minimum of relevant parameters with a maximum yield of information. Therefore, we inspected 'summary parameters' characteristic for whole classes of antioxidative metabolites and key enzymes. Results Three bioluminescence assays are presented. A horseradish peroxidase-based total antioxidative capacity (TAC assay is used to probe low molecular weight antioxidants. Peroxidases are quantified by their luminol converting activity (LUPO. Finally, we quantify high molecular weight superoxide anion scavenging activity (SOSA using coelenterazine. Experiments with Lepidium sativum L. show how salt, drought, cold, and heat influence the antioxidative system represented here by TAC, LUPO, SOSA, catalase, and glutathione reductase (GR. LUPO and SOSA run anti-parallel under all investigated stress conditions suggesting shifts in antioxidative functions rather than formation of antioxidative power. TAC runs in parallel with GR. This indicates that a majority of low molecular weight antioxidants in plants is represented by glutathione. Conclusion The set of assays presented here is capable of characterising antioxidative activities in plants. It is inexpensive, quick and reproducible and delivers quantitative data. 'Summary parameters' like TAC, LUPO, and SOSA are quantitative traits which may be promising for implementation in high-throughput screening for robustness of novel mutants, transgenics, or breeds.

  10. Oxidative stress in deep scattering layers: Heat shock response and antioxidant enzymes activities of myctophid fishes thriving in oxygen minimum zones

    Science.gov (United States)

    Lopes, Ana Rita; Trübenbach, Katja; Teixeira, Tatiana; Lopes, Vanessa M.; Pires, Vanessa; Baptista, Miguel; Repolho, Tiago; Calado, Ricardo; Diniz, Mário; Rosa, Rui

    2013-12-01

    Diel vertical migrators, such as myctophid fishes, are known to encounter oxygen minimum zones (OMZ) during daytime in the Eastern Pacific Ocean and, therefore, have to cope with temperature and oxidative stress that arise while ascending to warmer, normoxic surface waters at night-time. The aim of this study was to investigate the antioxidant defense strategies and heat shock response (HSR) in two myctophid species, namely Triphoturus mexicanus and Benthosema panamense, at shallow and warm surface waters (21 kPa, 20-25 °C) and at hypoxic, cold (≤1 kPa, 10 °C) mesopelagic depths. More specifically, we quantified (i) heat shock protein concentrations (HSP70/HSC70) (ii) antioxidant enzyme activities [including superoxide dismutase (SOD), catalase (CAT) and glutathione-S-transferase (GST)], and (iii) lipid peroxidation [malondialdehyde (MDA) levels]. HSP70/HSC70 levels increased in both myctophid species at warmer, well-oxygenated surface waters probably to prevent cellular damage (oxidative stress) due to increased oxygen demand under elevated temperatures and reactive oxygen species (ROS) formation. On the other hand, CAT and GST activities were augmented under hypoxic conditions, probably as preparatory response to a burst of oxyradicals during the reoxygenation phase (while ascending). SOD activity decreased under hypoxia in B. panamense, but was kept unchanged in T. mexicanus. MDA levels in B. panamense did not change between the surface and deep-sea conditions, whereas T. mexicanus showed elevated MDA and HSP70/HSC70 concentrations at warmer surface waters. This indicated that T. mexicanus seems to be not so well tuned to temperature and oxidative stress associated to diel vertical migrations. The understanding of such physiological strategies that are linked to oxygen deprivation and reoxygenation phases may provide valuable information about how different species might respond to the impacts of environmental stressors (e.g. expanding mesopelagic hypoxia

  11. Activity and Transcriptional Responses of Hepatopancreatic Biotransformation and Antioxidant Enzymes in the Oriental River Prawn Macrobrachium nipponense Exposed to Microcystin-LR

    Directory of Open Access Journals (Sweden)

    Julin Yuan

    2015-10-01

    Full Text Available Microcystins (MCs are a major group of cyanotoxins with side effects in many organisms; thus, compounds in this group are recognized as potent stressors and health hazards in aquatic ecosystems. In order to assess the toxicity of MCs and detoxification mechanism of freshwater shrimp Macrobrachium nipponense, the full-length cDNAs of the glutathione S-transferase (gst and catalase (cat genes were isolated from the hepatopancreas. The transcription level and activity changes in the biotransformation enzyme (glutathione S-transferase (GST and antioxidant enzymes (superoxide dismutase (SOD, catalase (CAT, glutathione peroxidase (GPx in the hepatopancreas of M. nipponense exposed to MC-LR (0.2, 1, 5, and 25 μg/L for 12, 24, 72 and 96 h were analyzed. The results showed that the isolated full-length cDNAs of cat and gst genes from M. nipponense displayed a high similarity to other crustaceans, and their mRNAs were mainly expressed in the hepatopancreas. MC-LR caused significant increase of GST activity following 48–96 h (p < 0.05 and an increase in SOD activity especially in 24- and 48-h exposures. CAT activity was activated when exposed to MC-LR in 12-, 24- and 48-h exposures and then it was inhibited at 96-h exposure. There was no significant effect on GPx activity after the 12- and 24-h exposures, whereas it was significantly stimulated after the 72- and 96-h exposures (p < 0.05. The transcription was altered similarly to enzyme activity, but the transcriptional response was generally more immediate and had greater amplitude than enzymatic response, particularly for GST. All of the results suggested that MC-LR can induce antioxidative modulation variations in M. nipponense hepatopancreas in order to eliminate oxidative damage.

  12. A teleostan homolog of catalase from black rockfish (Sebastes schlegelii): insights into functional roles in host antioxidant defense and expressional responses to septic conditions.

    Science.gov (United States)

    Elvitigala, Don Anushka Sandaruwan; Priyathilaka, Thanthrige Thiunuwan; Whang, Ilson; Nam, Bo-Hye; Lee, Jehee

    2015-05-01

    Antioxidative defense renders a significant protection against environmental stress in organisms and maintains the correct redox balance in cells, thereby supporting proper immune function. Catalase is an indispensable antioxidant in organisms that detoxifies hydrogen peroxides produced in cellular environments. In this study, we sought to molecularly characterize a homolog of catalase (RfCat), identified from black rockfish (Sebastes schlegelii). RfCat consists of a 1581 bp coding region for a protein of 527 amino acids, with a predicted molecular weight of 60 kD. The protein sequence of RfCat harbored similar domain architecture to known catalases, containing a proximal active site signature and proximal heme ligand signature, and further sharing prominent homology with its teleostan counterparts. As affirmed by multiple sequence alignments, most of the functionally important residues were well conserved in RfCat. Furthermore, our phylogenetic analysis indicates its common vertebrate ancestral origin and a close evolutionary relationship with teleostan catalases. Recombinantly expressed RfCat demonstrated prominent peroxidase activity that varied with different substrate and protein concentrations, and protected against DNA damage. RfCat mRNA was ubiquitously expressed among different tissues examined, as detected by qPCR. In addition, RfCat mRNA expression was modulated in response to pathogenic stress elicited by Streptococcus iniae and poly I:C in blood and spleen tissues. Collectively, our findings indicate that RfCat may play an indispensable role in host response to oxidative stress and maintain a correct redox balance after a pathogen invasion.

  13. Metastasized lung cancer suppression by Morinda citrifolia (Noni) leaf compared to Erlotinib via anti-inflammatory, endogenous antioxidant responses and apoptotic gene activation.

    Science.gov (United States)

    Lim, Swee-Ling; Mustapha, Noordin M; Goh, Yong-Meng; Bakar, Nurul Ain Abu; Mohamed, Suhaila

    2016-05-01

    Metastasized lung and liver cancers cause over 2 million deaths annually, and are amongst the top killer cancers worldwide. Morinda citrifolia (Noni) leaves are traditionally consumed as vegetables in the tropics. The macro and micro effects of M. citrifolia (Noni) leaves on metastasized lung cancer development in vitro and in vivo were compared with the FDA-approved anti-cancer drug Erlotinib. The extract inhibited the proliferation and induced apoptosis in A549 cells (IC50 = 23.47 μg/mL) and mouse Lewis (LL2) lung carcinoma cells (IC50 = 5.50 μg/mL) in vitro, arrested cancer cell cycle at G0/G1 phases and significantly increased caspase-3/-8 without changing caspase-9 levels. The extract showed no toxicity on normal MRC5 lung cells. Non-small-cell lung cancer (NSCLC) A549-induced BALB/c mice were fed with 150 and 300 mg/kg M. citrifolia leaf extract and compared with Erlotinib (50 mg/kg body weight) for 21 days. It significantly increased the pro-apoptotic TRP53 genes, downregulated the pro-tumourigenesis genes (BIRC5, JAK2/STAT3/STAT5A) in the mice tumours, significantly increased the anti-inflammatory IL4, IL10 and NR3C1 expression in the metastasized lung and hepatic cancer tissues and enhanced the NFE2L2-dependent antioxidant responses against oxidative injuries. The extract elevated serum neutrophils and reduced the red blood cells, haemoglobin, corpuscular volume and cell haemoglobin concentration in the lung cancer-induced mammal. It suppressed inflammation and oedema, and upregulated the endogenous antioxidant responses and apoptotic genes to suppress the cancer. The 300 mg/kg extract was more effective than the 50 mg/kg Erlotinib for most of the parameters measured.

  14. Metastasized lung cancer suppression by Morinda citrifolia (Noni) leaf compared to Erlotinib via anti-inflammatory, endogenous antioxidant responses and apoptotic gene activation.

    Science.gov (United States)

    Lim, Swee-Ling; Mustapha, Noordin M; Goh, Yong-Meng; Bakar, Nurul Ain Abu; Mohamed, Suhaila

    2016-05-01

    Metastasized lung and liver cancers cause over 2 million deaths annually, and are amongst the top killer cancers worldwide. Morinda citrifolia (Noni) leaves are traditionally consumed as vegetables in the tropics. The macro and micro effects of M. citrifolia (Noni) leaves on metastasized lung cancer development in vitro and in vivo were compared with the FDA-approved anti-cancer drug Erlotinib. The extract inhibited the proliferation and induced apoptosis in A549 cells (IC50 = 23.47 μg/mL) and mouse Lewis (LL2) lung carcinoma cells (IC50 = 5.50 μg/mL) in vitro, arrested cancer cell cycle at G0/G1 phases and significantly increased caspase-3/-8 without changing caspase-9 levels. The extract showed no toxicity on normal MRC5 lung cells. Non-small-cell lung cancer (NSCLC) A549-induced BALB/c mice were fed with 150 and 300 mg/kg M. citrifolia leaf extract and compared with Erlotinib (50 mg/kg body weight) for 21 days. It significantly increased the pro-apoptotic TRP53 genes, downregulated the pro-tumourigenesis genes (BIRC5, JAK2/STAT3/STAT5A) in the mice tumours, significantly increased the anti-inflammatory IL4, IL10 and NR3C1 expression in the metastasized lung and hepatic cancer tissues and enhanced the NFE2L2-dependent antioxidant responses against oxidative injuries. The extract elevated serum neutrophils and reduced the red blood cells, haemoglobin, corpuscular volume and cell haemoglobin concentration in the lung cancer-induced mammal. It suppressed inflammation and oedema, and upregulated the endogenous antioxidant responses and apoptotic genes to suppress the cancer. The 300 mg/kg extract was more effective than the 50 mg/kg Erlotinib for most of the parameters measured. PMID:27106908

  15. cAMP response element binding protein (CREB activates transcription via two distinct genetic elements of the human glucose-6-phosphatase gene

    Directory of Open Access Journals (Sweden)

    Stefano Luisa

    2005-01-01

    Full Text Available Abstract Background The enzyme glucose-6-phosphatase catalyzes the dephosphorylation of glucose-6-phosphatase to glucose, the final step in the gluconeogenic and glycogenolytic pathways. Expression of the glucose-6-phosphatase gene is induced by glucocorticoids and elevated levels of intracellular cAMP. The effect of cAMP in regulating glucose-6-phosphatase gene transcription was corroborated by the identification of two genetic motifs CRE1 and CRE2 in the human and murine glucose-6-phosphatase gene promoter that resemble cAMP response elements (CRE. Results The cAMP response element is a point of convergence for many extracellular and intracellular signals, including cAMP, calcium, and neurotrophins. The major CRE binding protein CREB, a member of the basic region leucine zipper (bZIP family of transcription factors, requires phosphorylation to become a biologically active transcriptional activator. Since unphosphorylated CREB is transcriptionally silent simple overexpression studies cannot be performed to test the biological role of CRE-like sequences of the glucose-6-phosphatase gene. The use of a constitutively active CREB2/CREB fusion protein allowed us to uncouple the investigation of target genes of CREB from the variety of signaling pathways that lead to an activation of CREB. Here, we show that this constitutively active CREB2/CREB fusion protein strikingly enhanced reporter gene transcription mediated by either CRE1 or CRE2 derived from the glucose-6-phosphatase gene. Likewise, reporter gene transcription was enhanced following expression of the catalytic subunit of cAMP-dependent protein kinase (PKA in the nucleus of transfected cells. In contrast, activating transcription factor 2 (ATF2, known to compete with CREB for binding to the canonical CRE sequence 5'-TGACGTCA-3', did not transactivate reporter genes containing CRE1, CRE2, or both CREs derived from the glucose-6-phosphatase gene. Conclusions Using a constitutively active CREB2

  16. Enhancement of DNA vaccine-induced immune responses by a 72-bp element from SV40 enhancer

    Institute of Scientific and Technical Information of China (English)

    LI Hai-shan; XU Jian-qing; HONG Kun-xue; SHAO Yi-ming; LIU Yong; LI Ding-feng; ZHANG Ran-ran; TANG Hai-li; ZHANG Yu-wei; HUANG Wei; LIU Ying; PENG Hong

    2007-01-01

    Background Although DNA vaccine is considered as the next generation of vaccine, most DNA vaccine candidates are still suffering from the relatively weak immunogenicity despite the increased dosage of plasmid DNA administered. In order to enhance the immune responses elicited by a codon-optimized HIV gag DNA vaccine, a modified plasmid vector pDRVI1.0 and a booster immunization with replicating Tiantan vaccinia (RTV) strain expressing the same gene were employed.Methods Vector pDRVI1.0 was constructed through inserting the 72-bp element from the SV40 enhancer, which was reported promoting nuclear transport of plasmid DNA, to the upstream of cytomegalovirus enhancer/promoter region of the plasmid vector pVR1012. Gene expression levels from expression plasmids based on pDRVI1.0 and pVR1012 were tested. Humoral and cellular immune responses induced by DNA vaccine alone or DNA prime-RTV boost regimen were determined in mice.Results It was shown that the 72-bp element significantly enhanced the gene expression level in non-dividing cells.gag-specific humoral and cellular immune responses induced by DNA vaccination were both significantly improved, while the Th1/Th2 balance was not obviously affected by the 72-bp element. RTV boosting further significantly enhanced DNA vaccine-primed antibody and T cell responses in a Th1-biased manner.Conclusions The 72-bp SV40 enhancer element should be included in the DNA vaccine vector and RTV strain is a very efficient live vector for boosting immunization.

  17. A negative retinoic acid response element in the rat oxytocin promoter restricts transcriptional stimulation by heterologous transactivation domains.

    OpenAIRE

    Lipkin, S. M.; Nelson, C. A.; Glass, C K; Rosenfeld, M G

    1992-01-01

    Retinoic acid receptors are ligand-dependent transcription factors that stimulate gene transcription from promoters containing retinoic acid or thyroid hormone response elements. We describe a high-affinity binding site from the rat oxytocin promoter that mediates negative transcriptional regulation by the retinoic acid receptor. To examine whether strong, constitutive transactivation domains would be capable of stimulating gene transcription when bound to this DNA binding site that normally ...

  18. A topology-motivated mixed finite element method for dynamic response of porous media

    OpenAIRE

    Lotfian, Zahrasadat; Sivaselvan, Mettupalayam

    2015-01-01

    In this paper, we propose a numerical method for computing solutions to Biot's fully dynamic model of incompressible saturated porous media [Biot;1956]. Our spatial discretization scheme is based on the three-field formulation (u-w-p) and the coupling of a lowest order Raviart-Thomas mixed element [Raviart,Thomas;1977] for fluid variable fields (w, p ) and a nodal Galerkin finite element for skeleton variable field (u). These mixed spaces are constructed based on the natural topology of the v...

  19. Dis3- and exosome subunit-responsive 3 Prime mRNA instability elements

    Energy Technology Data Exchange (ETDEWEB)

    Kiss, Daniel L.; Hou, Dezhi [Case Western Reserve University School of Medicine, Department of Molecular Biology and Microbiology, Cleveland, OH 44106 (United States); Gross, Robert H. [Dartmouth College, Department of Biological Sciences, Life Sciences Center 343, Hanover, NH 03755 (United States); Andrulis, Erik D., E-mail: exa32@case.edu [Case Western Reserve University School of Medicine, Department of Molecular Biology and Microbiology, Cleveland, OH 44106 (United States)

    2012-07-06

    Highlights: Black-Right-Pointing-Pointer Successful use of a novel RNA-specific bioinformatic tool, RNA SCOPE. Black-Right-Pointing-Pointer Identified novel 3 Prime UTR cis-acting element that destabilizes a reporter mRNA. Black-Right-Pointing-Pointer Show exosome subunits are required for cis-acting element-mediated mRNA instability. Black-Right-Pointing-Pointer Define precise sequence requirements of novel cis-acting element. Black-Right-Pointing-Pointer Show that microarray-defined exosome subunit-regulated mRNAs have novel element. -- Abstract: Eukaryotic RNA turnover is regulated in part by the exosome, a nuclear and cytoplasmic complex of ribonucleases (RNases) and RNA-binding proteins. The major RNase of the complex is thought to be Dis3, a multi-functional 3 Prime -5 Prime exoribonuclease and endoribonuclease. Although it is known that Dis3 and core exosome subunits are recruited to transcriptionally active genes and to messenger RNA (mRNA) substrates, this recruitment is thought to occur indirectly. We sought to discover cis-acting elements that recruit Dis3 or other exosome subunits. Using a bioinformatic tool called RNA SCOPE to screen the 3 Prime untranslated regions of up-regulated transcripts from our published Dis3 depletion-derived transcriptomic data set, we identified several motifs as candidate instability elements. Secondary screening using a luciferase reporter system revealed that one cassette-harboring four elements-destabilized the reporter transcript. RNAi-based depletion of Dis3, Rrp6, Rrp4, Rrp40, or Rrp46 diminished the efficacy of cassette-mediated destabilization. Truncation analysis of the cassette showed that two exosome subunit-sensitive elements (ESSEs) destabilized the reporter. Point-directed mutagenesis of ESSE abrogated the destabilization effect. An examination of the transcriptomic data from exosome subunit depletion-based microarrays revealed that mRNAs with ESSEs are found in every up-regulated mRNA data set but are

  20. Bimodal responses of cells to trace elements: insights into their mechanism of action using a biospectroscopy approach.

    Science.gov (United States)

    Llabjani, Valon; Hoti, Valmira; Pouran, Hamid M; Martin, Francis L; Zhang, Hao

    2014-10-01

    Understanding how organisms respond to trace elements is important because some are essential for normal bodily homeostasis, but can additionally be toxic at high concentrations. The inflection point for many of these elements is unknown and requires sensitive techniques capable of detecting subtle cellular changes as well as cytotoxic alterations. In this study, we treated human cells with arsenic (As), copper or selenium (Se) in a dose-response manner and used attenuated total reflection Fourier-transform infrared (ATR-FTIR) microspectroscopy combined with computational analysis to examine cellular alterations. Cell cultures were treated with As(V), Cu(2+) or Se(IV) at concentrations ranging from 0.001 mg L(-1) to 1000 mg L(-1) and their effects were spectrochemically determined. Results show that As(V) and Cu(2+) induce bimodal dose-response effects on cells; this is in line with hormesis-driven responses. Lipids and proteins seem to be the main cell targets for all the elements tested; however, each compound produced a unique fingerprint of effect. Spectral biomarkers indicate that all test agents generate reactive oxygen species (ROS), which could either stimulate repair mechanisms or induce damage in cells. PMID:25048930

  1. Androgen regulation of the TMPRSS2 gene and the effect of a SNP in an androgen response element.

    Science.gov (United States)

    Clinckemalie, Liesbeth; Spans, Lien; Dubois, Vanessa; Laurent, Michaël; Helsen, Christine; Joniau, Steven; Claessens, Frank

    2013-12-01

    More than 50% of prostate cancers have undergone a genomic reorganization that juxtaposes the androgen-regulated promoter of TMPRSS2 and the protein coding parts of several ETS oncogenes. These gene fusions lead to prostate-specific and androgen-induced ETS expression and are associated with aggressive lesions, poor prognosis, and early-onset prostate cancer. In this study, we showed that an enhancer at 13 kb upstream of the TMPRSS2 transcription start site is crucial for the androgen regulation of the TMPRSS2 gene when tested in bacterial artificial chromosomal vectors. Within this enhancer, we identified the exact androgen receptor binding sequence. This newly identified androgen response element is situated next to two binding sites for the pioneer factor GATA2, which were identified by DNase I footprinting. Both the androgen response element and the GATA-2 binding sites are involved in the enhancer activity. Importantly, a single nucleotide polymorphism (rs8134378) within this androgen response element reduces binding and transactivation by the androgen receptor. The presence of this SNP might have implications on the expression and/or formation levels of TMPRSS2 fusions, because both have been shown to be influenced by androgens.

  2. Structure of a Thyroid Hormone Receptor DNA-Binding Domain Homodimer Bound to an Inverted Palindrome DNA Response Element

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Yi; Young, Matthew A. (Michigan)

    2010-10-22

    Thyroid hormone receptor (TR), as a member of the nuclear hormone receptor family, can recognize and bind different classes of DNA response element targets as either a monomer, a homooligomer, or a heterooligomer. We report here the first crystal structure of a homodimer TR DNA-binding domain (DBD) in complex with an inverted repeat class of thyroid response element (TRE). The structure shows a nearly symmetric structure of the TR DBD assembled on the F2 TRE where the base recognition contacts in the homodimer DNA complex are conserved relative to the previously published structure of a TR-9-cis-retinoic acid receptor heterodimer DNA complex. The new structure also reveals that the T-box region of the DBD can function as a structural hinge that enables a large degree of flexibility in the position of the C-terminal extension helix that connects the DBD to the ligand-binding domain. Although the isolated TR DBDs exist as monomers in solution, we have measured highly cooperative binding of the two TR DBD subunits onto the inverted repeat DNA sequence. This suggests that elements of the DBD can influence the specific TR oligomerization at target genes, and it is not just interactions between the ligand-binding domains that are responsible for TR oligomerization at target genes. Mutational analysis shows that intersubunit contacts at the DBD C terminus account for some, but not all, of the cooperative homodimer TR binding to the inverted repeat class TRE.

  3. Prolonged inorganic arsenite exposure suppresses insulin-stimulated AKT S473 phosphorylation and glucose uptake in 3T3-L1 adipocytes: Involvement of the adaptive antioxidant response

    International Nuclear Information System (INIS)

    Highlights: → In 3T3-L1 adipocytes iAs3+ decreases insulin-stimulated glucose uptake. → iAs3+ attenuates insulin-induced phosphorylation of AKT S473. → iAs3+ activates the cellular adaptive oxidative stress response. → iAs3+ impairs insulin-stimulated ROS signaling. → iAs3+ decreases expression of adipogenic genes and GLUT4. -- Abstract: There is growing evidence that chronic exposure of humans to inorganic arsenic, a potent environmental oxidative stressor, is associated with the incidence of type 2 diabetes (T2D). One critical feature of T2D is insulin resistance in peripheral tissues, especially in mature adipocytes, the hallmark of which is decreased insulin-stimulated glucose uptake (ISGU). Despite the deleterious effects of reactive oxygen species (ROS), they have been recognized as a second messenger serving an intracellular signaling role for insulin action. Nuclear factor erythroid 2-related factor 2 (NRF2) is a central transcription factor regulating cellular adaptive response to oxidative stress. This study proposes that in response to arsenic exposure, the NRF2-mediated adaptive induction of endogenous antioxidant enzymes blunts insulin-stimulated ROS signaling and thus impairs ISGU. Exposure of differentiated 3T3-L1 cells to low-level (up to 2 μM) inorganic arsenite (iAs3+) led to decreased ISGU in a dose- and time-dependent manner. Concomitant to the impairment of ISGU, iAs3+ exposure significantly attenuated insulin-stimulated intracellular ROS accumulation and AKT S473 phosphorylation, which could be attributed to the activation of NRF2 and induction of a battery of endogenous antioxidant enzymes. In addition, prolonged iAs3+ exposure of 3T3-L1 adipocytes resulted in significant induction of inflammatory response genes and decreased expression of adipogenic genes and glucose transporter type 4 (GLUT4), suggesting chronic inflammation and reduction in GLUT4 expression may also be involved in arsenic-induced insulin resistance in adipocytes

  4. Prolonged inorganic arsenite exposure suppresses insulin-stimulated AKT S473 phosphorylation and glucose uptake in 3T3-L1 adipocytes: Involvement of the adaptive antioxidant response

    Energy Technology Data Exchange (ETDEWEB)

    Xue, Peng [The Hamner Institutes for Health Sciences, Research Triangle Park, NC 27709 (United States); School of Public Health, China Medical University, Shenyang 110001 (China); Hou, Yongyong; Zhang, Qiang; Woods, Courtney G.; Yarborough, Kathy; Liu, Huiyu [The Hamner Institutes for Health Sciences, Research Triangle Park, NC 27709 (United States); Sun, Guifan [School of Public Health, China Medical University, Shenyang 110001 (China); Andersen, Melvin E. [The Hamner Institutes for Health Sciences, Research Triangle Park, NC 27709 (United States); Pi, Jingbo, E-mail: jpi@thehamner.org [The Hamner Institutes for Health Sciences, Research Triangle Park, NC 27709 (United States)

    2011-04-08

    Highlights: {yields} In 3T3-L1 adipocytes iAs{sup 3+} decreases insulin-stimulated glucose uptake. {yields} iAs{sup 3+} attenuates insulin-induced phosphorylation of AKT S473. {yields} iAs{sup 3+} activates the cellular adaptive oxidative stress response. {yields} iAs{sup 3+} impairs insulin-stimulated ROS signaling. {yields} iAs{sup 3+} decreases expression of adipogenic genes and GLUT4. -- Abstract: There is growing evidence that chronic exposure of humans to inorganic arsenic, a potent environmental oxidative stressor, is associated with the incidence of type 2 diabetes (T2D). One critical feature of T2D is insulin resistance in peripheral tissues, especially in mature adipocytes, the hallmark of which is decreased insulin-stimulated glucose uptake (ISGU). Despite the deleterious effects of reactive oxygen species (ROS), they have been recognized as a second messenger serving an intracellular signaling role for insulin action. Nuclear factor erythroid 2-related factor 2 (NRF2) is a central transcription factor regulating cellular adaptive response to oxidative stress. This study proposes that in response to arsenic exposure, the NRF2-mediated adaptive induction of endogenous antioxidant enzymes blunts insulin-stimulated ROS signaling and thus impairs ISGU. Exposure of differentiated 3T3-L1 cells to low-level (up to 2 {mu}M) inorganic arsenite (iAs{sup 3+}) led to decreased ISGU in a dose- and time-dependent manner. Concomitant to the impairment of ISGU, iAs{sup 3+} exposure significantly attenuated insulin-stimulated intracellular ROS accumulation and AKT S473 phosphorylation, which could be attributed to the activation of NRF2 and induction of a battery of endogenous antioxidant enzymes. In addition, prolonged iAs{sup 3+} exposure of 3T3-L1 adipocytes resulted in significant induction of inflammatory response genes and decreased expression of adipogenic genes and glucose transporter type 4 (GLUT4), suggesting chronic inflammation and reduction in GLUT4

  5. Identification of two-component system elements downstream of AHK5 in the stomatal closure response of Arabidopsis thaliana.

    Science.gov (United States)

    Mira-Rodado, Virtudes; Veerabagu, Manikandan; Witthöft, Janika; Teply, Julia; Harter, Klaus; Desikan, Radhika

    2012-11-01

    To optimize water use efficiency, plants regulate stomatal closure through a complex signaling process. Hydrogen peroxide (H₂O₂) is produced in response to several environmental stimuli, and has been identified as a key second messenger involved in the regulation of stomatal aperture. The Arabidopsis histidine kinase 5 (AHK5) has been shown to regulate stomatal closure in response to H₂O₂ and other stimuli that depend on H₂O₂. AHK5 is a member of the two-component system (TCS) in Arabidopsis. The plant TCS comprises three different protein types: the hybrid histidine kinases (HKs), the phosphotransfer proteins (HPs) and the response regulators (RRs). Here we determined TCS elements involved in H₂O₂- and ethylene-dependent stomatal closure downstream of AHK5. By yeast and in planta interaction assays and functional studies, AHP1, 2 and 5 as well as the response regulators ARR4 and ARR7 were identified acting downstream of AHK5 in the ethylene and H₂O₂ response pathways of guard cells. Furthermore, we demonstrate that aspartate phosphorylation of ARR4 is only required for the H₂O₂- but not for the ethylene-induced stomatal closure response. Our data suggest the presence of a complex TCS signaling network comprising of at least AHK5, several AHPs and response regulators, which modulate stomatal closure in response to H₂O₂ and ethylene.

  6. Response to the Report of the Transfermium Working Group ''Discovery of the Transfermium Elements''

    International Nuclear Information System (INIS)

    In the opinion of the authors the report of the Transfermium Working Group (TWG) ''Discovery of the Transfermium Elements'' is riddled with errors of omission and commission. Many relevant references and much relevant data were omitted as a result of the selective use of references and data. There were only two members representing the International Union of Applied Chemistry (IUPAC) on the TWG ( and these were not nuclear chemists) while there were seven members representing the International Union of Applied Physics (IUPAP). Much of the experimental evidence is of a basically chemical nature and its proper evaluation would have benefited from the presence of more nuclear chemists on the TWG. Especially grievous is the rejection of the Berkeley claim to the 1955 discovery of element 101 which was based on a clear-cut chemical identification. Our most serious quarrel with the TWG report is their treatment of the discovery of element 104. It is clearly a waste of time and effort to reopen the cases of elements 102 and 103, which were discovered more than 30 years ago with the approval of the suggested names by the IUPAC according to the standards of that era. (Author)

  7. Small intestinal response to 'elemental' and 'complete' liquid feeds in the rat: effect of dietary bulk.

    Science.gov (United States)

    Maxton, D G; Cynk, E U; Thompson, R P

    1987-06-01

    The effect of oral isocaloric feeding on small intestinal structure and function was studied in the rat. The liquid 'elemental' enteral feed Vivonex HN, the liquid 'complete' feed Ensure and the same liquid complete feed with 9% bulk Enrich were compared with solid chow containing 21% bulk (normal rat chow), all given for four weeks. Weight gain was significantly less in the group fed Vivonex HN than that of any other groups. The bulkless Vivonex HN and Ensure increased proximal jejunal mass compared to Enrich with 9% bulk or to normal rat chow. Jejunal mucosal DNA and protein levels also tended to be higher in Ensure and Vivonex HN fed animals, as was jejunal sugar absorption. In the terminal ileum, however, total weight was decreased by both elemental and complete feeds with and without bulk, but particularly by the elemental diet. Bulkless feeds therefore increase jejunal and reduce terminal ileal mass. The striking atrophy of the terminal ileum produced by the elemental diet may be important for its efficacy in treating inflammatory bowel disease. PMID:3040541

  8. Optimization of Reflux Conditions for Total Flavonoid and Total Phenolic Extraction and Enhanced Antioxidant Capacity in Pandan (Pandanus amaryllifolius Roxb. Using Response Surface Methodology

    Directory of Open Access Journals (Sweden)

    Ali Ghasemzadeh

    2014-01-01

    Full Text Available Response surface methodology was applied to optimization of the conditions for reflux extraction of Pandan (Pandanus amaryllifolius Roxb. in order to achieve a high content of total flavonoids (TF, total phenolics (TP, and high antioxidant capacity (AC in the extracts. Central composite experimental design with three factors and three levels was employed to consider the effects of the operation parameters, including the methanol concentration (MC, 40%–80%, extraction temperature (ET, 40–70°C, and liquid-to-solid ratio (LS ratio, 20–40 mL/g on the properties of the extracts. Response surface plots showed that increasing these operation parameters induced the responses significantly. The TF content and AC could be maximized when the extraction conditions (MC, ET, and LS ratio were 78.8%, 69.5°C, and 32.4 mL/g, respectively, whereas the TP content was optimal when these variables were 75.1%, 70°C, and 31.8 mL/g, respectively. Under these optimum conditions, the experimental TF and TP content and AC were 1.78, 6.601 mg/g DW, and 87.38%, respectively. The optimized model was validated by a comparison of the predicted and experimental values. The experimental values were found to be in agreement with the predicted values, indicating the suitability of the model for optimizing the conditions for the reflux extraction of Pandan.

  9. Response of growth and antioxidant enzymes in Azolla plants (Azolla pinnata and Azolla filiculoides) exposed to UV-B.

    Science.gov (United States)

    Masood, Amjad; Zeeshan, M; Abraham, G

    2008-06-01

    Effect of ultravilolet-B (0.4 Wm(-2)) irradiation on growth, flavonoid content, lipid peroxidation, proline accumulation and activities of superoxide dismutase and peroxidase was comparatively analysed in Azolla pinnata and Azolla filiculoides. Growth measured as increment in dry weight reduced considerably due to all UV-B treatments. However, the reduction was found to be severe in A. filiculoides as compared to A. pinnata. The level of UV-absorbing compound flavonoids increased significantly in A. pinnata plants whereas only a slight increase in the flavonoid content was observed in A. filiculoides. UV-B exposure led to enhanced production of malondialdehyde (MDA) and electrolyte leakage in A. filiculoides than A. pinnata. Proline accumulation also showed a similar trend. Marked differences in the activity of antioxidant enzymes such as superoxide dismutase (SOD) and peroxidase (POD) was noticed in both the plants exposed to UV-B. Our comparative studies indicate A. pinnata to be better tolerant to UV-B as compared with A. filiculoides which appears to be sensitive. PMID:18637563

  10. Combined effects of ammonia and microcystin on survival, growth, antioxidant responses, and lipid peroxidation of bighead carp Hypophthalmythys nobilis larvae.

    Science.gov (United States)

    Sun, Hongjie; Lü, Kai; Minter, Ewan J A; Chen, Yafen; Yang, Zhou; Montagnes, David J S

    2012-06-30

    Hazardous materials, such as ammonia and microcystin, are released into lakes during cyanobacterial bloom degradation and may severely impact aquatic organisms. To assess the combined effects of ammonia and microcystin on survival, growth, and oxidative stress of larval fish, 14-day-old larvae of bighead carp Hypophthalmythys nobilis were exposed to solutions with different combined concentrations of ammonia (0, 0.06, 0.264mgL(-1)) and microcystin (0, 2, 10, 30μgL(-1)) for 10 days. Microcystin significantly decreased body length, while ammonia significantly increased body weight, specific growth rate, and condition factor, but there was no significant interaction between ammonia and microcystin on them. Superoxide dismutase, catalase, and malondialdehyde significantly changed with microcystin concentration, whereas glutathione was not affected by microcystin. Ammonia significantly affected the antioxidant system. There were significant interactions between ammonia and microcystin on superoxide dismutase and malondialdehyde. Our data clearly demonstrate that ammonia and microcystin adversely affect bighead carp larvae. PMID:22560242

  11. 33 CFR Appendix D to Part 154 - Training Elements for Oil Spill Response Plans

    Science.gov (United States)

    2010-07-01

    ... training (HAZWOPER). 1.2The training section of the plan need not be a detailed course syllabus, but it....6Familiarity with the contracting and ordering procedures to acquire oil spill removal organization resources... members in accordance with designated job responsibilities. 2.2.10Responsibilities and authority of...

  12. A topology-motivated mixed finite element method for dynamic response of porous media

    CERN Document Server

    Lotfian, Zahrasadat

    2015-01-01

    In this paper, we propose a numerical method for computing solutions to Biot's fully dynamic model of incompressible saturated porous media [Biot;1956]. Our spatial discretization scheme is based on the three-field formulation (u-w-p) and the coupling of a lowest order Raviart-Thomas mixed element [Raviart,Thomas;1977] for fluid variable fields (w, p ) and a nodal Galerkin finite element for skeleton variable field (u). These mixed spaces are constructed based on the natural topology of the variables; hence, are physically compatible and able to exactly model the kind of continuity which is expected. The method automatically satisfies the well known LBB (inf-sup) stability condition and avoids locking that usually occurs in the numerical computations in the incompressible limit and very low hydraulic conductivity. In contrast to the majority of approaches, our three-field formulation can fully capture dynamic behavior of porous media even in high frequency loading phenomena with considerable fluid acceleratio...

  13. Small intestinal response to 'elemental' and 'complete' liquid feeds in the rat: effect of dietary bulk.

    OpenAIRE

    Maxton, D. G.; Cynk, E U; Thompson, R P

    1987-01-01

    The effect of oral isocaloric feeding on small intestinal structure and function was studied in the rat. The liquid 'elemental' enteral feed Vivonex HN, the liquid 'complete' feed Ensure and the same liquid complete feed with 9% bulk Enrich were compared with solid chow containing 21% bulk (normal rat chow), all given for four weeks. Weight gain was significantly less in the group fed Vivonex HN than that of any other groups. The bulkless Vivonex HN and Ensure increased proximal jejunal mass ...

  14. Responses of hematological parameters, beta-endorphin, cortisol, reactive oxygen metabolites, and biological antioxidant potential in horses participating in a traditional tournament.

    Science.gov (United States)

    Pazzola, M; Pira, E; Sedda, G; Vacca, G M; Cocco, R; Sechi, S; Bonelli, P; Nicolussi, P

    2015-04-01

    Several concerns have been raised over the health of animals used in equestrian games that have their origins in historical or religious events and are currently held in many countries. This study investigated physiological stress response and health status of horses participating in the Sartiglia, a historical horse tournament held in the city of Oristano, Italy, which is principally based on the attempts of masked horsemen at a gallop to run a sword through a hole in a suspended silver star. Blood samples were collected from 21 horses the day before the tournament (D0), during the tournament (D1), and the day after the tournament (D2). Samples were analyzed for complete blood count and biochemical, hormonal, and oxidative stress assays. Data were analyzed using the mixed effect model with sampling session as one of the fixed effects. On the whole, blood parameters evidenced an optimal health status of horses at D0. Significant dehydration and increase of circulating glucose, enzymes, cortisol, and β-endorphin were registered at D1 (P < 0.001) with a complete recovery of physiological values just at D2. The reactive oxygen metabolites (d-ROM), from which the prooxidant activity can be evaluated, showed an increase from D0 to D1 and D2. Concentration of biological antioxidant potential, which measured the antioxidant capacity, was characterized by the maximum level registered during the tournament and counteracted the simultaneous increase of d-ROM. It can be hypothesized that the tournament played an important role in causing high levels of oxidant markers not only because of the physical exercise represented by the gallop but also because the emotional stressors. In conclusion, the tournament caused significant changes of most parameters, which rapidly recovered to baseline values within the day after. These data will certainly be useful for a future implementation of tests in equine medicine and for the improvements of knowledge of changes of blood parameters

  15. Evaluation, prediction and optimization the ultrasound-assisted extraction method using response surface methodology: antioxidant and biological properties of Stachys parviflora L.

    Science.gov (United States)

    Bashi, Davoud Salar; Dowom, Samaneh Attaran; Bazzaz, Bibi Sedigheh Fazly; Khanzadeh, Farhad; Soheili, Vahid; Mohammadpour, Ali

    2016-01-01

    Objective(s): To optimize the extraction method using response surface methodology, extract the phenolic compounds, and identify the antioxidant and biological properties of Stachys parviflora L. extracts. Materials and Methods: Maceration and ultrasound-assisted extraction (UAE) (4, 7, 10 min treatment time, 40, 70, 100 % high-intensity and 60, 80, 100 % (v v-1) methanol purity) were applied to obtain the extracts. SEM was conducted to provide the microstructure of the extracted plant. MICs (colorimetric assay), MFCs (colony diameter), total phenolic content, total flavonoid content, radical scavenging capacity and extraction efficiency were determined. HPLC analysis was applied to measure the existent phenolic compounds. Results: A quadratic model (4 min treatment time, 74.5 % high-intensity and 74.2 % solvent purity) was suggested as the best (TPC: 20.89 mg GAE g-1 d.m., TFC: 6.22 mg QEs g-1 d.m., DPPH IC50: 21.86 µg ml-1 and EE: 113.65 mg g-1 d.m.) UAE extraction model. The optimized UAE extract was generally more effective against Gram-positive microorganisms (MIC: 10-20; MBC: 10-40 (mg ml-1)) than Gram-negative ones (MIC: 40; MBC: >40 (mg ml-1)). Moreover, it (MGI: 2.32-100 %) revealed more anti-mold activity than maceration (MGI: <28.77 %). Explosive disruption of the cell walls, therefore, enhanced extraction yield by acoustic cavitation, was elucidated using SEM. Caffeic acid, tannic acid, quercetin, trans ferulic acid and rosmarinic acid were determined as the phenolic compounds in the optimized extract. Conclusion: RSM optimization was successfully applied for UAE from S. parviflora. The considerable antioxidant and biological properties were attributed to the phenolic compounds. PMID:27403260

  16. Accumulation and detoxification dynamics of microcystin-LR and antioxidant responses in male red swamp crayfish Procambarus clarkii.

    Science.gov (United States)

    Yuan, Julin; Gu, Zhimin; Zheng, Yao; Zhang, Yingying; Gao, Jiancao; Chen, Shu; Wang, Zaizhao

    2016-08-01

    MC-LR is one of major microcystin isoforms with potent hepatotoxicity. In the present study, we aim to: 1) explore the dynamics of MC-LR accumulation and elimination in different tissues of male red swamp crayfish Procambarus clarkii; 2) reveal the mechanisms underlying hepatic antioxidation and detoxification. In the semi-static toxicity tests under the water temperature of 25±2°C, P. clarkii were exposed to 0.1, 1, 10 and 100μg/L MC-LR for 7days for accumulation and subsequently relocated to freshwater for another 7days to depurate MC-LR. MC-LR was measured in the hepatopancreas, intestine, abdominal muscle and gill by HPLC. The enzyme activities of superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx) and glutathione S-transferase (GST), content of glutathione (GSH), and transcripts of Mn-sod, cat, gpx1, Mu-gst, heat shock protein90 (hsp90), hsp70 and hsp60 in hepatopancreas were detected. The results showed that P. clarkii accumulated more MC-LR in intestine, and less in abdominal muscle and gill during accumulation period and eliminated the toxin more quickly in gill and abdominal muscle, and comparatively slowly in intestine during depuration period. The fast increase of SOD and CAT activities at early stage, subsequent decrease at later stage of accumulation period and then fast increase during depuration period were partially consistent with the transcriptional changes of their respective genes. GPx was activated by longer MC-LR exposure and gpx1 mRNA expression showed uncoordinated regulation pattern compared with its enzyme. Hsp genes were up-regulated when P. clarkii was exposed to MC-LR. PMID:27218425

  17. Phenolics and flavonoids compounds, phenylanine ammonia lyase and antioxidant activity responses to elevated CO₂ in Labisia pumila (Myrisinaceae).

    Science.gov (United States)

    Jaafar, Hawa Z E; Ibrahim, Mohd Hafiz; Karimi, Ehsan

    2012-01-01

    A split plot 3 × 3 experiment was designed to examine the impact of three concentrations of CO₂ (400, 800 and 1,200 μmol·mol⁻¹) on the phenolic and flavonoid compound profiles, phenylalanine ammonia lyase (PAL) and antioxidant activity in three varieties of Labisia pumila Benth. (var. alata, pumila and lanceolata) after 15 weeks of exposure. HPLC analysis revealed a strong influence of increased CO₂ concentration on the modification of phenolic and flavonoid profiles, whose intensity depended on the interaction between CO₂ levels and L. pumila varieties. Gallic acid and quercetin were the most abundant phenolics and flavonoids commonly present in all the varieties. With elevated CO₂ (1,200 μmol·mol⁻¹) exposure, gallic acid increased tremendously, especially in var. alata and pumila (101-111%), whilst a large quercetin increase was noted in var. lanceolata (260%), followed closely by alata (201%). Kaempferol, although detected under ambient CO₂ conditions, was undetected in all varieties after exposure. Instead, caffeic acid was enhanced tremendously in var. alata (338~1,100%) and pumila (298~433%). Meanwhile, pyragallol and rutin were only seen in var. alata (810 μg·g⁻¹ DW) and pumila (25 μg·g⁻¹ DW), respectively, under ambient conditions; but the former compound went undetected in all varieties while rutin continued to increase by 262% after CO₂ enrichment. Interestingly, naringenin that was present in all varieties under ambient conditions went undetected under enrichment, except for var. pumila where it was enhanced by 1,100%. PAL activity, DPPH and FRAP also increased with increasing CO₂ levels implying the possible improvement of health-promoting quality of Malaysian L. pumila under high CO₂ enrichment conditions. PMID:22634843

  18. Thyroid hormone-regulated gene expression in juvenile mouse liver: identification of thyroid response elements using microarray profiling and in silico analyses

    Directory of Open Access Journals (Sweden)

    Paquette Martin A

    2011-12-01

    Full Text Available Abstract Background Disruption of thyroid hormone signalling can alter growth, development and energy metabolism. Thyroid hormones exert their effects through interactions with thyroid receptors that directly bind thyroid response elements and can alter transcriptional activity of target genes. The effects of short-term thyroid hormone perturbation on hepatic mRNA transcription in juvenile mice were evaluated, with the goal of identifying genes containing active thyroid response elements. Thyroid hormone disruption was induced from postnatal day 12 to 15 by adding goitrogens to dams' drinking water (hypothyroid. A subgroup of thyroid hormone-disrupted pups received intraperitoneal injections of replacement thyroid hormones four hours prior to sacrifice (replacement. An additional group received only thyroid hormones four hours prior to sacrifice (hyperthyroid. Hepatic mRNA was extracted and hybridized to Agilent mouse microarrays. Results Transcriptional profiling enabled the identification of 28 genes that appeared to be under direct thyroid hormone-regulation. The regulatory regions of the genome adjacent to these genes were examined for half-site sequences that resemble known thyroid response elements. A bioinformatics search identified 33 thyroid response elements in the promoter regions of 13 different genes thought to be directly regulated by thyroid hormones. Thyroid response elements found in the promoter regions of Tor1a, 2310003H01Rik, Hect3d and Slc25a45 were further validated by confirming that the thyroid receptor is associated with these sequences in vivo and that it can bind directly to these sequences in vitro. Three different arrangements of thyroid response elements were identified. Some of these thyroid response elements were located far up-stream (> 7 kb of the transcription start site of the regulated gene. Conclusions Transcriptional profiling of thyroid hormone disrupted animals coupled with a novel bioinformatics search

  19. Mathematical model of uptake and metabolism of arsenic(III in human hepatocytes - Incorporation of cellular antioxidant response and threshold-dependent behavior

    Directory of Open Access Journals (Sweden)

    Isukapalli Sastry S

    2011-01-01

    Full Text Available Abstract Background Arsenic is an environmental pollutant, potent human toxicant, and oxidative stress agent with a multiplicity of health effects associated with both acute and chronic exposures. A semi-mechanistic cellular-level toxicokinetic (TK model was developed in order to describe the uptake, biotransformation and clearance of arsenical species in human hepatocytes. Notable features of this model are the incorporation of arsenic-glutathione complex formation and a "switch-like" formulation to describe the antioxidant response of hepatocytes to arsenic exposure. Results The cellular-level TK model applies mass action kinetics in order to predict the concentrations of trivalent and pentavalent arsenicals in hepatocytes. The model simulates uptake of arsenite (iAsIII via aquaporin isozymes 9 (AQP9s, glutathione (GSH conjugation, methylation by arsenic methyltransferase (AS3MT, efflux through multidrug resistant proteins (MRPs and the induced antioxidant response via thioredoxin reductase (TR activity. The model was parameterized by optimization of model estimates for arsenite (iAsIII, monomethylated (MMA and dimethylated (DMA arsenicals concentrations with time-course experimental data in human hepatocytes for a time span of 48 hours, and dose-response data at 24 hours for a range of arsenite concentrations from 0.1 to 10 μM. Global sensitivity analysis of the model showed that at low doses the transport parameters had a dominant role, whereas at higher doses the biotransformation parameters were the most significant. A parametric comparison of the TK model with an analogous model developed for rat hepatocytes from the literature demonstrated that the biotransformation of arsenite (e.g. GSH conjugation has a large role in explaining the variation in methylation between rats and humans. Conclusions The cellular-level TK model captures the temporal modes of arsenical accumulation in human hepatocytes. It highlighted the key biological

  20. Yield and Mineral Element Concentration of Beetroot in Response to Nutrient Source in Hydroponic Solution

    OpenAIRE

    Egilla, Jonathan N.

    2009-01-01

    The yield and mineral element concentration of beetroot (Beta vulgaris ‘Bulls Blood’) was determined in a closed nutrient-recirculating ‘Nutrient Film Technique’ (NFT) hydroponic experiment. Seedlings were grown and harvested 42 days after transfer into NFT system (DAT), either with a commercial hydroponic fertilizer or a non-hydroponic soluble fertilizer containing in mg liter-1: 108 nitrogen (N) and 12 calcium (Ca) (N1Ca1), or 200 N and 66.7 Ca (N2Ca2), respectively. Nutrient source had no ...

  1. Impulse response of anistropic composite plates with a higher-order theory and finite element discretization

    International Nuclear Information System (INIS)

    The global safety of nuclear power plants is greatly affected by the resistance of internal and external plate and shell-type structures to dynamic loads caused by accidentally generated flying objects, such as parts of failed rotating equipment or ruptured piping, tornado missiles or impacting aircraft engines. This paper describes the development of a linear and nonlinear laminated plate dynamics computer program based on explicit time integration with a special mass matrix diagonalization scheme using a higher-order theory and Co finite elements. A Lagrangian approach is adopted for the geometric nonlinear analysis and the stress and strain descriptions used are those due to Piola-Kirchhoff and Green respectively

  2. Study of the Internal Mechanical response of an asphalt mixture by 3-D Discrete Element Modeling

    DEFF Research Database (Denmark)

    Feng, Huan; Pettinari, Matteo; Hofko, Bernhard;

    2015-01-01

    and the reliability of which have been validated. The dynamic modulus of asphalt mixtures were predicted by conducting Discrete Element simulation under dynamic strain control loading. In order to reduce the calculation time, a method based on frequency–temperature superposition principle has been implemented....... The ball density effect on the internal stress distribution of the asphalt mixture model has been studied when using this method. Furthermore, the internal stresses under dynamic loading have been studied. The agreement between the predicted and the laboratory test results of the complex modulus shows...

  3. Photosynthetic Characteristics and Antioxidative Metabolism of Flag Leaves in Responses to Nitrogen Application During Grain Filling of Field-Grown Wheat

    Institute of Scientific and Technical Information of China (English)

    CAI Rui-guo; WANG Zhen-lin; ZHANG Min; YIN Yan-ping; WANG Ping; ZHANG Ti-bin; GU Feng; DAI Zhong-min; LIANG Tai-bo; WU Yun-hai

    2008-01-01

    A two-factorial experiment was conducted with two wheat cultivars,SN1391(large spike and large grain)and GC8901(multiple spike and medium grain),and two nitrogen(N)application rates(12 and 24 g N m-2),to investigate the responses of photosynthetic characteristics and antioxidative metabolism to nitrogen rates in flag leaves of field-grown wheat during grain filling.The results showed that the content of N and chlorophyll(Chl)in wheat flag leaves decreased after anthesis and the net photosynthetic rate(Pn),effective quantum yield of PS II(ΦPS Ⅱ),efficiency of excitation capture by open PS H reaction centers(Fv'/Fm'),and photochemical quenching coefficient(qp)began to decrease at 14 days after anthesis.However,the maximal efficiency of PS II photochemistry(Fv/Fm)decreased slightly until the late period of senescence and the nonphotochemical quenching coefficient(NPQ)increased during flag leaves' senescence.As a result,a conflict came into being between absorption and utilization to light energy in flag leaves during senescence,which might accelerate the senescence of flag leaves.Compared with GC8901,the lower plant population of SN1391during grain filling was helpful to maintain the higher content of photosynthetic pigment,activity of PS U,and Pn in flag leaves during senescence.The delayed decrease in antioxidative enzyme activity and the lower degree of membrane lipid peroxidation in the senescing leaves of SN1391 were beneficial to protect the photosynthetic apparatus,which lead to the prolonged duration of CO2 assimilation.With the increase of N application,the Chl content of SN1391 flag leaves and the efficiency of excitation captured by open PS II centers increased.At the same time,the thermal dissipation in SN1391 flag leaves at high N(HN)treatment decreased and ?PsⅡimproved greatly,which were favorable to the increase of Pn.The SOD,POD,CAT and APX activities in the flag leaves of SN1391 increased markedly at HN treatment,indicating that these enzymes

  4. Quantitative analysis of polycomb response elements (PREs at identical genomic locations distinguishes contributions of PRE sequence and genomic environment

    Directory of Open Access Journals (Sweden)

    Okulski Helena

    2011-03-01

    Full Text Available Abstract Background Polycomb/Trithorax response elements (PREs are cis-regulatory elements essential for the regulation of several hundred developmentally important genes. However, the precise sequence requirements for PRE function are not fully understood, and it is also unclear whether these elements all function in a similar manner. Drosophila PRE reporter assays typically rely on random integration by P-element insertion, but PREs are extremely sensitive to genomic position. Results We adapted the ΦC31 site-specific integration tool to enable systematic quantitative comparison of PREs and sequence variants at identical genomic locations. In this adaptation, a miniwhite (mw reporter in combination with eye-pigment analysis gives a quantitative readout of PRE function. We compared the Hox PRE Frontabdominal-7 (Fab-7 with a PRE from the vestigial (vg gene at four landing sites. The analysis revealed that the Fab-7 and vg PREs have fundamentally different properties, both in terms of their interaction with the genomic environment at each site and their inherent silencing abilities. Furthermore, we used the ΦC31 tool to examine the effect of deletions and mutations in the vg PRE, identifying a 106 bp region containing a previously predicted motif (GTGT that is essential for silencing. Conclusions This analysis showed that different PREs have quantifiably different properties, and that changes in as few as four base pairs have profound effects on PRE function, thus illustrating the power and sensitivity of ΦC31 site-specific integration as a tool for the rapid and quantitative dissection of elements of PRE design.

  5. Aging response of the Ti-Nb system biomaterials with β-stabilizing elements

    International Nuclear Information System (INIS)

    Effects of aging temperature and the contents of β-stabilizing elements on the composition of martensite α'' in two Ti-Nb alloys and the resulting mechanical properties were investigated for biomedical applications. The microstructures were examined by means of optical microscopy (OM) and X-ray diffraction (XRD). Vickers hardness, compressive elastic modulus and the yield strength have been measured. The results show that the decomposition mode of the martensite α'' in two studied alloys depends on aging treatment and the contents of β-stabilizing elements. Various microstructures such as α, (α + β) and (β + ω) phases were observed to precipitate in the studied alloys after the aging treatments performed at 523 K, 773 K, 883 K and 1023 K for 0.5 h, respectively. Afterwards, the Ti-24Nb-6Zr-7.5Sn-2Fe alloy was aged at 773 K for 1 h. The compressive elastic modulus and mechanical properties of the two alloys are found to be sensitive to the microstructural change caused by aging temperature. For the Ti-24Nb-6Zr-7.5Sn-2Fe alloy, after aging at 773 K for 1 h, its yield strength, compressive elastic modulus and Vickers hardness reach 846 MPa, 26 GPa and 398 HV, respectively. This aged alloy exhibits proper comprehensive mechanical property and strength-to-modulus ratio for biomedical implant applications.

  6. Antioxidative defense

    Directory of Open Access Journals (Sweden)

    Stevanović Jelka

    2011-01-01

    Full Text Available Free radicals occur constantly during metabolism and take part in numerous physiological processes, such as: intra-cellular and inter-cellular signalization, gene expression, removal of damaged or senescent cells, and control of the tone of blood vessels. However, there is an increased quantity of free radicals in situations of so-called oxidative stress, when they cause serious damage to cellular membranes (peroxidation of their lipids, damage of membrane proteins, and similar, to interior cellular protein molecules, as well as DNA molecules and carbohydrates. This is precisely why the organism has developed numerous mechanisms for removing free radicals and/or preventing their production. Some of these are enzyme-related and include superoxide-dismutase, catalase, glutathione-peroxidase, and others. Other, non-enzyme mechanisms, imply antioxidative activities of vitamins E and C, provitamin A, coenzyme Q, reduced glutation, and others. Since free radicals can leave the cell that has produced them and become dispersed throughout the body, in addition to antioxidative defense that functions within cellular structures, antioxidant extra-cellular defense has also been developed. This is comprised by: transferrin, lactoferrin, haptoglobin, hemopexin, ceruloplasmin, albumins, extra-cellular isoform SOD, extracellular glutathione-peroxidase, glucose, bilirubin, urates, and many other molecules.

  7. Non-linear finite element analysis for prediction of seismic response of buildings considering soil-structure interaction

    Directory of Open Access Journals (Sweden)

    E. Çelebi

    2012-11-01

    Full Text Available The objective of this paper focuses primarily on the numerical approach based on two-dimensional (2-D finite element method for analysis of the seismic response of infinite soil-structure interaction (SSI system. This study is performed by a series of different scenarios that involved comprehensive parametric analyses including the effects of realistic material properties of the underlying soil on the structural response quantities. Viscous artificial boundaries, simulating the process of wave transmission along the truncated interface of the semi-infinite space, are adopted in the non-linear finite element formulation in the time domain along with Newmark's integration. The slenderness ratio of the superstructure and the local soil conditions as well as the characteristics of input excitations are important parameters for the numerical simulation in this research. The mechanical behavior of the underlying soil medium considered in this prediction model is simulated by an undrained elasto-plastic Mohr-Coulomb model under plane-strain conditions. To emphasize the important findings of this type of problems to civil engineers, systematic calculations with different controlling parameters are accomplished to evaluate directly the structural response of the vibrating soil-structure system. When the underlying soil becomes stiffer, the frequency content of the seismic motion has a major role in altering the seismic response. The sudden increase of the dynamic response is more pronounced for resonance case, when the frequency content of the seismic ground motion is close to that of the SSI system. The SSI effects under different seismic inputs are different for all considered soil conditions and structural types.

  8. Development of electrochemical reporter assay using HeLa cells transfected with vector plasmids encoding various responsive elements

    Energy Technology Data Exchange (ETDEWEB)

    Shiku, Hitoshi, E-mail: shiku@bioinfo.che.tohoku.ac.jp [Graduate School of Environmental Studies, Tohoku University, 6-6-11-604 Aramaki-Aoba, Sendai 980-8579 (Japan); Takeda, Michiaki; Murata, Tatsuya [Graduate School of Environmental Studies, Tohoku University, 6-6-11-604 Aramaki-Aoba, Sendai 980-8579 (Japan); Akiba, Uichi; Hamada, Fumio [Graduate School of Engineering and Resource Science, Akita University, 1-1 Tegata gakuen-machi, Akita 010-8502 (Japan); Matsue, Tomokazu, E-mail: matsue@bioinfo.che.tohoku.ac.jp [Graduate School of Environmental Studies, Tohoku University, 6-6-11-604 Aramaki-Aoba, Sendai 980-8579 (Japan)

    2009-04-27

    Electrochemical assay using HeLa cell lines transfected with various plasmid vectors encoding SEAP (secreted alkaline phosphatase) as the reporter has been performed by using SECM (scanning electrochemical microscopy). The plasmid vector contains different responsive elements that include GRE (glucocorticoid response elements), CRE (cAMP responsive elements), or {kappa}B (binding site for NF{kappa}B (nuclear factor kappa B)) upstream of the SEAP sequence. The transfected HeLa cells were patterned on a culture dish in a 4 x 4 array of circles of diameter 300 {mu}m by using the PDMS (poly(dimethylsiloxane)) stencil technique. The cellular array was first exposed to 100 ng mL{sup -1} dexamethasone, 10 ng mL{sup -1} forskolin, or 100 ng mL{sup -1} TNF-{alpha} (tumor necrosis factor {alpha}) after which it was further cultured in an RPMI culture medium for 6 h. After incubation, the cellular array was soaked in a measuring solution containing 4.7 mM PAPP (p-aminophenylphosphate) at pH 9.5, following which electrochemical measurements were performed immediately within 40 min. The SECM method allows parallel evaluation of different cell lines transfected with pGRE-SEAP, pCRE-SEAP, and pNF{kappa}B-SEAP patterned on the same solid support for detection of the oxidation current of PAP (p-aminophenol) flux produced from only 300 HeLa cells in each stencil pattern. The results of the SECM method were highly sensitive as compared to those obtained from the conventional CL (chemiluminescence) protocol with at least 5 x 10{sup 4} cells per well.

  9. Regulation of CYP3A4 by pregnane X receptor: The role of nuclear receptors competing for response element binding

    Energy Technology Data Exchange (ETDEWEB)

    Istrate, Monica A., E-mail: monicai@scripps.edu [Dr. Margarete Fischer-Bosch-Institute of Clinical Pharmacology, Stuttgart, Germany, and University of Tuebingen, Auerbachstr. 112, D-70376 Stuttgart (Germany); Nussler, Andreas K., E-mail: nuessler@uchir.me.tum.de [Department of Traumatology, Technical University Munich, Ismaningerstr. 22, 81675 Munich (Germany); Eichelbaum, Michel, E-mail: michel.eichelbaum@ikp-stuttgart.de [Dr. Margarete Fischer-Bosch-Institute of Clinical Pharmacology, Stuttgart, Germany, and University of Tuebingen, Auerbachstr. 112, D-70376 Stuttgart (Germany); Burk, Oliver, E-mail: oliver.burk@ikp-stuttgart.de [Dr. Margarete Fischer-Bosch-Institute of Clinical Pharmacology, Stuttgart, Germany, and University of Tuebingen, Auerbachstr. 112, D-70376 Stuttgart (Germany)

    2010-03-19

    Induction of the major drug metabolizing enzyme CYP3A4 by xenobiotics contributes to the pronounced interindividual variability of its expression and often results in clinically relevant drug-drug interactions. It is mainly mediated by PXR, which regulates CYP3A4 expression by binding to several specific elements in the 5' upstream regulatory region of the gene. Induction itself shows a marked interindividual variability, whose underlying determinants are only partly understood. In this study, we investigated the role of nuclear receptor binding to PXR response elements in CYP3A4, as a potential non-genetic mechanism contributing to interindividual variability of induction. By in vitro DNA binding experiments, we showed that several nuclear receptors bind efficiently to the proximal promoter ER6 and distal xenobiotic-responsive enhancer module DR3 motifs. TR{alpha}1, TR{beta}1, COUP-TFI, and COUP-TFII further demonstrated dose-dependent repression of PXR-mediated CYP3A4 enhancer/promoter reporter activity in transient transfection in the presence and absence of the PXR inducer rifampin, while VDR showed this effect only in the absence of treatment. By combining functional in vitro characterization with hepatic expression analysis, we predict that TR{alpha}1, TR{beta}1, COUP-TFI, and COUP-TFII show a strong potential for the repression of PXR-mediated activation of CYP3A4 in vivo. In summary, our results demonstrate that nuclear receptor binding to PXR response elements interferes with PXR-mediated expression and induction of CYP3A4 and thereby contributes to the interindividual variability of induction.

  10. Estrogen induction of the cyclin D1 promoter: Involvement of a cAMP response-like element

    OpenAIRE

    Sabbah, Michele; Courilleau, Delphine; Mester, Jan; Redeuilh, Gerard

    1999-01-01

    Estrogens induce cell proliferation in target tissues by stimulating progression through the G1 phase of the cell cycle. Induction of cyclin D1 expression is a critical feature of the mitogenic action of estrogen. We have determined a region between −96 and −29 in the cyclin D1 promoter that confers regulation by estrogens in the human mammary carcinoma cells MCF-7. This region encompasses a unique known transcription factor binding site with a sequence of a potential cAMP response element (C...

  11. A Bioinformatics Method for the Design of Live Attenuated Virus Vaccine Utilizing Host MicroRNA Response Elements.

    Science.gov (United States)

    Wichadakul, Duangdao

    2016-01-01

    The host microRNA machinery has been employed to control viral replication. To improve safety for live attenuated virus vaccines, the binding sites of the host microRNAs, so-called microRNA response elements (MREs), were incorporated into the virus sequences. These MREs were typically designed for a specific host microRNA and virus sequence with the effectiveness evaluated by experimental trials. Here, we describe a computational flow that can be used to simultaneously design and prioritize the effective MREs in large-scale.

  12. On the antioxidant properties of erythropoietin and its association with the oxidative–nitrosative stress response to hypoxia in humans

    DEFF Research Database (Denmark)

    Bailey, D M; Lundby, C; Berg, R M G;

    2014-01-01

    ˙) radicals was evaluated in-vitro. The relationship between the erythopoietic and oxidative-nitrosative stress response to poikilocapneic hypoxia was determined separately in-vivo by sampling arterial blood from eleven males in normoxia and following 12 h exposure to 13% oxygen. Electron paramagnetic...... in nitric oxide, indicative of oxidative-nitrosative stress. The latter was confirmed by an increased systemic formation of A˙(-) , PBN-OR, 3-NT and corresponding loss of NO2- (P stress responses were consistently related (r = -0.52 to 0...

  13. Identification and Characterization of iron-responsive regulatory elements in Pseudomonas syringae pv tomato DC3000

    Science.gov (United States)

    Pseudomonas syringae pv. tomato DC3000 (DC3000) is a model bacterial pathogen of tomato and Arabidopsis thaliana. This bacterium must sense and respond to a variety of environmental signals and understanding how the bacterium integrates these signals into a physiological response is central to our u...

  14. 33 CFR Appendix C to Part 155 - Training Elements for Oil Spill Response Plans

    Science.gov (United States)

    2010-07-01

    ... supervise shore-based response resources. 2.2.14Actions to take, in accordance with designated job... receive the necessary worker safety training (HAZWOPER). 1.2The training section of the plan need not be a... organization resources. 2.2.9Familiarity with the Area Contingency Plans. 2.2.10Familiarity with...

  15. Identification of hookworm DAF-16/FOXO response elements and direct gene targets.

    Directory of Open Access Journals (Sweden)

    Xin Gao

    Full Text Available BACKGROUND: The infective stage of the parasitic nematode hookworm is developmentally arrested in the environment and needs to infect a specific host to complete its life cycle. The canine hookworm (Ancylostoma caninum is an excellent model for investigating human hookworm infections. The transcription factor of A. caninum, Ac-DAF-16, which has a characteristic fork head or "winged helix" DNA binding domain (DBD, has been implicated in the resumption of hookworm development in the host. However, the precise roles of Ac-DAF-16 in hookworm parasitism and its downstream targets are unknown. In the present study, we combined molecular techniques and bioinformatics to identify a group of Ac-DAF-16 binding sites and target genes. METHODOLOGY/PRINCIPAL FINDINGS: The DNA binding domain of Ac-DAF-16 was used to select genomic fragments by in vitro genomic selection. Twenty four bound genomic fragments were analyzed for the presence of the DAF-16 family binding element (DBE and possible alternative Ac-DAF-16 bind motifs. The 22 genes linked to these genomic fragments were identified using bioinformatics tools and defined as candidate direct gene targets of Ac-DAF-16. Their developmental stage-specific expression patterns were examined. Also, a new putative DAF-16 binding element was identified. CONCLUSIONS/SIGNIFICANCE: Our results show that Ac-DAF-16 is involved in diverse biological processes throughout hookworm development. Further investigation of these target genes will provide insights into the molecular basis by which Ac-DAF-16 regulates its downstream gene network in hookworm infection.

  16. Serum lipid and antioxidant responses in hypercholesterolemic men and women receiving plant sterol esters vary by apolipoprotein E genotype

    Science.gov (United States)

    Plant sterol esters reduce serum total cholesterol (TC) and LDL cholesterol (LDL-C), but with striking inter-individual variability. In this randomized, double-blind, controlled study, serum lipid, plant sterol, fat-soluble vitamin, and carotenoid responses to plant sterols were studied according to...

  17. Identification of a Gene Sharing a Promoter and Peroxisome Proliferator-Response Elements With Acyl-CoA Oxidase Gene

    Directory of Open Access Journals (Sweden)

    Mst. Hasina Akter

    2006-01-01

    Full Text Available Many mammalian genes are clustered on the genomes, and hence the genes in the same cluster can be regulated through a common regulatory element. We indeed showed previously that the perilipin/PEX11α gene pair is transactivated tissue-selectively by PPARγ and PPARα, respectively, through a common binding site. In the present study, we identified a gene, named GSPA, neighboring a canonical PPAR target, acyl-CoA oxidase (AOX gene. GSPA expression was induced by a peroxisome proliferator, Wy14,643, in the liver of wild-type mice, but not PPARα-null mice. GSPA and AOX share the promoter and two peroxisome proliferator-response elements. GSPA mRNA was also found in the heart and skeletal muscle, as well as 3T3-L1 cells. GSPA encodes a protein of 161 amino acids that is enriched in 3T3-L1 cells. Even other gene pairs might be regulated through common sequence elements, and conversely it would be interesting how each gene is aptly regulated in clusters.

  18. Extraction of Antioxidants from Borage (Borago officinalis L. Leaves—Optimization by Response Surface Method and Application in Oil-in-Water Emulsions

    Directory of Open Access Journals (Sweden)

    Francisco Segovia

    2014-05-01

    Full Text Available Borage (Borago officinalis L. is a typical Spanish plant. During processing, 60% are leaves. The aim of this work is to model and optimize the extraction of polyphenol from borage leaves using the response surface method (RSM and to use this extract for application in emulsions. The responses were: total polyphenol content (TPC, antioxidant capacity by ORAC, and rosmarinic acid by HPLC. The ranges of the variables temperature, ethanol content and time were 50–90 °C, 0%–30%–60% ethanol (v/v, and 10–15 min. For ethanolic extraction, optimal conditions were at 75.9 °C, 52% ethanol and 14.8 min, yielding activity of 27.05 mg GAE/g DW TPC; 115.96 mg TE/g DW in ORAC and 11.02 mg/L rosmarinic acid. For water extraction, optimal activity was achieved with extraction at 98.3 °C and 22 min, with responses of 22.3 mg GAE/g DW TPC; 81.6 mg TE/g DW in ORAC and 3.9 mg/L rosmarinic acid. The significant variables were ethanol concentration and temperature. For emulsions, the peroxide value was inhibited by 60% for 3% extract concentration; and 80% with 3% extract concentration and 0.2% of BSA. The p-anisidine value between the control and the emulsion with 3% extract was reduced to 73.6% and with BSA 86.3%, and others concentrations had similar behavior.

  19. Extraction of Antioxidants from Borage (Borago officinalis L.) Leaves—Optimization by Response Surface Method and Application in Oil-in-Water Emulsions

    Science.gov (United States)

    Segovia, Francisco; Lupo, Bryshila; Peiró, Sara; Gordon, Michael H.; Almajano, María Pilar

    2014-01-01

    Borage (Borago officinalis L.) is a typical Spanish plant. During processing, 60% are leaves. The aim of this work is to model and optimize the extraction of polyphenol from borage leaves using the response surface method (RSM) and to use this extract for application in emulsions. The responses were: total polyphenol content (TPC), antioxidant capacity by ORAC, and rosmarinic acid by HPLC. The ranges of the variables temperature, ethanol content and time were 50–90 °C, 0%–30%–60% ethanol (v/v), and 10–15 min. For ethanolic extraction, optimal conditions were at 75.9 °C, 52% ethanol and 14.8 min, yielding activity of 27.05 mg GAE/g DW TPC; 115.96 mg TE/g DW in ORAC and 11.02 mg/L rosmarinic acid. For water extraction, optimal activity was achieved with extraction at 98.3 °C and 22 min, with responses of 22.3 mg GAE/g DW TPC; 81.6 mg TE/g DW in ORAC and 3.9 mg/L rosmarinic acid. The significant variables were ethanol concentration and temperature. For emulsions, the peroxide value was inhibited by 60% for 3% extract concentration; and 80% with 3% extract concentration and 0.2% of BSA. The p-anisidine value between the control and the emulsion with 3% extract was reduced to 73.6% and with BSA 86.3%, and others concentrations had similar behavior. PMID:26784875

  20. Extraction of Antioxidants from Borage (Borago officinalis L.) Leaves-Optimization by Response Surface Method and Application in Oil-in-Water Emulsions.

    Science.gov (United States)

    Segovia, Francisco; Lupo, Bryshila; Peiró, Sara; Gordon, Michael H; Almajano, María Pilar

    2014-01-01

    Borage (Borago officinalis L.) is a typical Spanish plant. During processing, 60% are leaves. The aim of this work is to model and optimize the extraction of polyphenol from borage leaves using the response surface method (RSM) and to use this extract for application in emulsions. The responses were: total polyphenol content (TPC), antioxidant capacity by ORAC, and rosmarinic acid by HPLC. The ranges of the variables temperature, ethanol content and time were 50-90 °C, 0%-30%-60% ethanol (v/v), and 10-15 min. For ethanolic extraction, optimal conditions were at 75.9 °C, 52% ethanol and 14.8 min, yielding activity of 27.05 mg GAE/g DW TPC; 115.96 mg TE/g DW in ORAC and 11.02 mg/L rosmarinic acid. For water extraction, optimal activity was achieved with extraction at 98.3 °C and 22 min, with responses of 22.3 mg GAE/g DW TPC; 81.6 mg TE/g DW in ORAC and 3.9 mg/L rosmarinic acid. The significant variables were ethanol concentration and temperature. For emulsions, the peroxide value was inhibited by 60% for 3% extract concentration; and 80% with 3% extract concentration and 0.2% of BSA. The p-anisidine value between the control and the emulsion with 3% extract was reduced to 73.6% and with BSA 86.3%, and others concentrations had similar behavior. PMID:26784875

  1. Estrogen modulates in vitro T cell responses in a concentration- and receptor-dependent manner: effects on intracellular molecular targets and antioxidant enzymes.

    Science.gov (United States)

    Priyanka, Hannah P; Krishnan, Harini C; Singh, Ran Vijay; Hima, Lalgi; Thyagarajan, Srinivasan

    2013-12-01

    Estrogen is a key hormone in facilitating ovulation and maintenance of pregnancy in young females and subsequent decline in its production contributes to the development of age-associated disorders such as hormone-dependent cancer, osteoporosis, and cardiovascular diseases. The mechanisms through which estrogen promotes female-specific diseases with advancing age are unclear especially, its effects on immune system which is vital for the maintenance of homeostasis and health. Although the diverse effects of estrogen on Th immunity (Th1 vs. Th2) have been characterized in several cell-types and animal models, there is no direct mechanistic study to understand its immunomodulatory actions. The purpose of this study is to investigate whether the in vitro effects of 17β-estradiol on lymphocytes from the spleen influence cell-mediated immune responses based on its concentration and type of estrogen receptors (ERs) and to assess its mechanism of action at the cellular level. Lymphocytes from the spleens of young Sprague-Dawley rats were isolated and incubated with various concentrations of 17β-estradiol (10(-6)-10(-14)M) and specific ERα- and β-agonists (10(-6)M, 10(-8)M and 10(-10)M) without or with concanavalin A (Con A) to measure T lymphocyte proliferation, IFN-γ and IL-2 production, p-ERK 1/2, p-CREB, and p-Akt, activities of antioxidant enzymes[superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GPx)], and nitric oxide (NO) production. The specificity of ER-mediated actions in lymphocytes was examined by coincubation with nonspecific ER antagonists ICI(182,780) or tamoxifen. Lower concentrations of 17β-estradiol enhanced proliferation of T lymphocytes and IFN-γ production without or with Con A stimulation but had no effect on IL-2 production. ERα and ERβ agonists induced an increase in T cell proliferation and IFN-γ production and these effects were inhibited by tamoxifen. ERβ agonist alone enhanced IL-2 production by the lymphocytes

  2. Reactor elements properties response during a postulated loss-of-coolant accident (LOCA)

    International Nuclear Information System (INIS)

    Four computer algorithms have been introduced to solve for the reactor different materials response subjected to LOCA conditions, they were developed with the intent of producing a simple, accurate and efficient prediction schemes. A general overview of the solution procedures design and working of each of four algorithms are presented, followed by short description of the nature of solution and calculated results. These algorithms are: 1. ZIRCP to give the cladding material properties response under normal and transient conditions. 2. FCGAPP to give the fuel- cladding gas-gap conductivity. 3. NFUEIP to solve the temperature dependent of nuclear fuel properties during normal and transient conditions. 4. TSDATP has been developed to solve for the thermodynamic and transport properties of water and steam over a large range of temperature and pressure. 14 fig

  3. Simplified Boundary Element Method for Kinematic Response of Single Piles in Two-Layer Soil

    OpenAIRE

    Fayun Liang; Haibing Chen; Wei Dong Guo

    2013-01-01

    A simple approach is formulated to predict the elastic, kinematic pile bending during harmonic or transient excitation for a circular pile (rather than a simplified thin strip). The kinematic response of a pile embedded in two-layer soil is resolved in the frequency domain caused by the upward propagation of shear waves from the underlying bedrock. The simplified approach is generally valid to nonhomogeneous soil profiles, in light of the good comparison with the dynamic FE method and BDWF so...

  4. A Novel Heme-responsive Element Mediates Transcriptional Regulation in Caenorhabditis elegans*

    OpenAIRE

    Sinclair, Jason; Hamza, Iqbal

    2010-01-01

    Hemes are prosthetic groups that participate in diverse biochemical pathways across phylogeny. Although heme can also regulate broad physiological processes by directly modulating gene expression in Metazoa, the regulatory pathways for sensing and responding to heme are not well defined. Caenorhabditis elegans is a heme auxotroph and relies solely on environmental heme for sustenance. Worms respond to heme availability by regulating heme-responsive genes such as hrg-1, an intestinal heme tran...

  5. Elements That Regulate the DNA Damage Response of Proteins Defective in Cockayne Syndrome.

    Science.gov (United States)

    Iyama, Teruaki; Wilson, David M

    2016-01-16

    Cockayne syndrome (CS) is a premature aging disorder characterized by developmental defects, multisystem progressive degeneration and sensitivity to ultraviolet light. CS is divided into two primary complementation groups, A and B, with the CSA and CSB proteins presumably functioning in DNA repair and transcription. Using laser microirradiation and confocal microscopy, we characterized the nature and regulation of the CS protein response to oxidative DNA damage, double-strand breaks (DSBs), angelicin monoadducts and trioxsalen interstrand crosslinks (ICLs). Our data indicate that CSB recruitment is influenced by the type of DNA damage and is most rapid and robust as follows: ICLs>DSBs>monoadducts>oxidative lesions. Transcription inhibition reduced accumulation of CSB at sites of monoadducts and ICLs, but it did not affect recruitment to (although slightly affected retention at) oxidative damage. Inhibition of histone deacetylation altered the dynamics of CSB assembly, suggesting a role for chromatin status in the response to DNA damage, whereas the proteasome inhibitor MG132 had no effect. The C-terminus of CSB and, in particular, its ubiquitin-binding domain were critical to recruitment, while the N-terminus and a functional ATPase domain played a minor role at best in facilitating protein accumulation. Although the absence of CSA had no effect on CSB recruitment, CSA itself localized at sites of ICLs, DSBs and monoadducts but not at oxidative lesions. Our results reveal molecular components of the CS protein response and point to a major involvement of complex lesions in the pathology of CS.

  6. Micoses superficiais e os elementos da resposta imune Superficial mycosis and the immune response elements

    Directory of Open Access Journals (Sweden)

    Paulo Ricardo Criado

    2011-08-01

    Full Text Available As micoses superficiais são prevalentes em todo o mundo, geralmente ocasionadas por dermatófitos e restritas à camada córnea. A resposta imunológica do hospedeiro às infecções dos fungos dermatófitos depende basicamente das defesas do hospedeiro a metabólitos do fungo, da virulência da cepa ou da espécie infectante e da localização anatômica da infecção. Serão revistos alguns dos fatores da defesa imunológica do hospedeiro que influenciam na eficácia da resposta imune. Em especial, a participação dos receptores de padrão de reconhecimento (PRRs, tais como os receptores toll-like ou os da família lectina (DC-SIGN e dectin-2, que participam da resposta imune inata, conferindo-lhe especificidade e definindo o padrão da resposta imune como um todo. O predomínio celular ou humoral da resposta imune definirá o quadro clínico e o prognóstico da infecção, levando à cura ou cronicidadeSuperficial mycoses are prevalent worldwide. They are often caused by dermatophytes and restricted to the stratum corneum. The host's immune response against infections caused by dermatophytes basically depends on the host's defense against metabolites of the fungi, virulence of the infecting strain or species and anatomical site of the infection. We will review some of the factors of the host's immune defense that influence the efficacy of the immune response. We will particularly review the role of pattern recognition receptors (PRRs, such as toll-like receptors or lectin receptors (DCSIGN and Dectin 2, which participate in the innate immune response, bringing specificity to the immune response and setting its pattern. The predominance of a cellular or humoral immune response determines the clinical manifestations and the prognosis of the infection, leading to healing or chronicity

  7. Molecular cloning and expression of the carbohydrate response element binding protein gene and related genes involved in hepatic lipogenesis during post-hatch development of broiler chickens

    Science.gov (United States)

    Carbohydrate response element binding protein (ChREBP) and sterol regulatory element binding protein-1c (SREBP-1c) are known to be key regulators of glucose metabolism and lipid synthesis in mammals. Responding to changes in the level of glucose (ChREBP) and insulin (SREBP-1c), these two transcripti...

  8. Response surface methodology for evaluation and optimization of process parameter and antioxidant capacity of rice flour modified by enzymatic extrusion.

    Science.gov (United States)

    Xu, Enbo; Pan, Xiaowei; Wu, Zhengzong; Long, Jie; Li, Jingpeng; Xu, Xueming; Jin, Zhengyu; Jiao, Aiquan

    2016-12-01

    For the purpose of investigating the effect of enzyme concentration (EC), barrel temperature (BT), moisture content (MC), and screw speed (SS) on processing parameters (product temperature, die pressure and special mechanical energy (SME)) and product responses (extent of gelatinization (GE), retention rate of total phenolic content (TPC-RR)), rice flour extruded with thermostable α-amylase was analyzed by response surface methodology. Stepwise regression models were computed to generate response surface and contour plots, revealing that both TPC-RR and GE increased as increasing MC while expressed different sensitivities to BT during enzymatic extrusion. Phenolics preservation was benefited from low SME. According to multiple-factor optimization, the conditions required to obtain the target SME (10kJ/kg), GE (100%) and TPC-RR (85%) were: EC=1.37‰, BT=93.01°C, MC=44.30%, and SS=171.66rpm, with the actual values (9.49kJ/kg, 99.96% and 87.10%, respectively) showing a good fit to the predicted values. PMID:27374518

  9. Identification of Regulatory Mutations in SERPINC1 Affecting Vitamin D Response Elements Associated with Antithrombin Deficiency

    Science.gov (United States)

    Toderici, Mara; de la Morena-Barrio, María Eugenia; Padilla, José; Miñano, Antonia; Antón, Ana Isabel; Iniesta, Juan Antonio; Herranz, María Teresa; Fernández, Nuria; Vicente, Vicente; Corral, Javier

    2016-01-01

    Antithrombin is a crucial anticoagulant serpin whose even moderate deficiency significantly increases the risk of thrombosis. Most cases with antithrombin deficiency carried genetic defects affecting exons or flanking regions of SERPINC1.We aimed to identify regulatory mutations inSERPINC1 through sequencing the promoter, intron 1 and 2 of this gene in 23 patients with antithrombin deficiency but without known genetic defects. Three cases with moderate antithrombin deficiency (63–78%) carried potential regulatory mutations. One located 200 bp before the initiation ATG and two in intron 1. These mutations disrupted two out of five potential vitamin D receptor elements (VDRE) identified in SERPINC1 with different software. One genetic defect, c.42-1060_-1057dupTTGA, was a new low prevalent polymorphism (MAF: 0.01) with functional consequences on plasma antithrombin levels. The relevance of the vitamin D pathway on the regulation of SERPINC1 was confirmed in a cell model. Incubation of HepG2 with paricalcitol, a vitamin D analog, increased dose-dependently the levels of SERPINC1transcripts and antithrombin released to the conditioned medium. This study shows further evidence of the transcriptional regulation of SERPINC1 by vitamin D and first describes the functional and pathological relevance of mutations affecting VDRE of this gene. Our study opens new perspectives in the search of new genetic defects involved in antithrombin deficiency and the risk of thrombosis as well as in the design of new antithrombotic treatments. PMID:27003919

  10. Explicit incremental-update algorithm for modeling crystal elasto-viscoplastic response in finite element simulation

    Institute of Scientific and Technical Information of China (English)

    LI Hong-wei; YANG He; SUN Zhi-chao

    2006-01-01

    Computational stability and efficiency are the key problems for numerical modeling of crystal plasticity,which will limit its development and application in finite element (FE) simulation evidently. Since implicit iterative algorithms are inefficient and have difficulty to determine initial values,an explicit incremental-update algorithm for the elasto-viscoplastic constitutive relation was developed in the intermediate frame by using the second Piola-Kirchoff (P-K) stress and Green stain. The increment of stress and slip resistance were solved by a calculation loop of linear equations sets. The reorientation of the crystal as well as the elastic strain can be obtained from a polar decomposition of the elastic deformation gradient. User material subroutine VUMAT was developed to combine crystal elasto-viscoplastic constitutive model with ABAQUS/Explicit. Numerical studies were performed on a cubic upset model with OFHC material (FCC crystal). The comparison of the numerical results with those obtained by implicit iterative algorithm and those from experiments demonstrates that the explicit algorithm is reliable. Furthermore,the effect rules of material anisotropy,rate sensitivity coefficient (RSC) and loading speeds on the deformation were studied. The numerical studies indicate that the explicit algorithm is suitable and efficient for large deformation analyses where anisotropy due to texture is important.

  11. Responses of antioxidant enzyme and photosynthesis in rape seedling to the combined stresses of acid rain and ultraviolet-B radiation

    Institute of Scientific and Technical Information of China (English)

    LIANG Chan-juan; HUANG Xiao-hua; TAO Wen-yi; ZHOU Qing

    2005-01-01

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

  12. β-Radiation Stress Responses on Growth and Antioxidative Defense System in Plants: A Study with Strontium-90 in Lemna minor.

    Science.gov (United States)

    Van Hoeck, Arne; Horemans, Nele; Van Hees, May; Nauts, Robin; Knapen, Dries; Vandenhove, Hildegarde; Blust, Ronny

    2015-01-01

    In the following study, dose dependent effects on growth and oxidative stress induced by β-radiation were examined to gain better insights in the mode of action of β-radiation induced stress in plant species. Radiostrontium (⁹⁰Sr) was used to test for β-radiation induced responses in the freshwater macrophyte Lemna minor. The accumulation pattern of 90Sr was examined for L. minor root and fronds separately over a seven-day time period and was subsequently used in a dynamic dosimetric model to calculate β-radiation dose rates. Exposing L. minor plants for seven days to a ⁹⁰Sr activity concentration of 25 up to 25,000 kBq·L⁻¹ resulted in a dose rate between 0.084 ± 0.004 and 97 ± 8 mGy·h⁻¹. After seven days of exposure, root fresh weight showed a dose dependent decrease starting from a dose rate of 9.4 ± 0.5 mGy·h⁻¹. Based on these data, an EDR10 value of 1.5 ± 0.4 mGy·h⁻¹ was estimated for root fresh weight and 52 ± 17 mGy·h⁻¹ for frond fresh weight. Different antioxidative enzymes and metabolites were further examined to analyze if β-radiation induces oxidative stress in L. minor. PMID:26198226

  13. β-Radiation Stress Responses on Growth and Antioxidative Defense System in Plants: A Study with Strontium-90 in Lemna minor

    Science.gov (United States)

    Van Hoeck, Arne; Horemans, Nele; Van Hees, May; Nauts, Robin; Knapen, Dries; Vandenhove, Hildegarde; Blust, Ronny

    2015-01-01

    In the following study, dose dependent effects on growth and oxidative stress induced by β-radiation were examined to gain better insights in the mode of action of β-radiation induced stress in plant species. Radiostrontium (90Sr) was used to test for β-radiation induced responses in the freshwater macrophyte Lemna minor. The accumulation pattern of 90Sr was examined for L. minor root and fronds separately over a seven-day time period and was subsequently used in a dynamic dosimetric model to calculate β-radiation dose rates. Exposing L. minor plants for seven days to a 90Sr activity concentration of 25 up to 25,000 kBq·L−1 resulted in a dose rate between 0.084 ± 0.004 and 97 ± 8 mGy·h−1. After seven days of exposure, root fresh weight showed a dose dependent decrease starting from a dose rate of 9.4 ± 0.5 mGy·h−1. Based on these data, an EDR10 value of 1.5 ± 0.4 mGy·h−1 was estimated for root fresh weight and 52 ± 17 mGy·h−1 for frond fresh weight. Different antioxidative enzymes and metabolites were further examined to analyze if β-radiation induces oxidative stress in L. minor. PMID:26198226

  14. β-Radiation Stress Responses on Growth and Antioxidative Defense System in Plants: A Study with Strontium-90 in Lemna minor

    Directory of Open Access Journals (Sweden)

    Arne Van Hoeck

    2015-07-01

    Full Text Available In the following study, dose dependent effects on growth and oxidative stress induced by β-radiation were examined to gain better insights in the mode of action of β-radiation induced stress in plant species. Radiostrontium (90Sr was used to test for β-radiation induced responses in the freshwater macrophyte Lemna minor. The accumulation pattern of 90Sr was examined for L. minor root and fronds separately over a seven-day time period and was subsequently used in a dynamic dosimetric model to calculate β-radiation dose rates. Exposing L. minor plants for seven days to a 90Sr activity concentration of 25 up to 25,000 kBq·L−1 resulted in a dose rate between 0.084 ± 0.004 and 97 ± 8 mGy·h−1. After seven days of exposure, root fresh weight showed a dose dependent decrease starting from a dose rate of 9.4 ± 0.5 mGy·h−1. Based on these data, an EDR10 value of 1.5 ± 0.4 mGy·h−1 was estimated for root fresh weight and 52 ± 17 mGy·h−1 for frond fresh weight. Different antioxidative enzymes and metabolites were further examined to analyze if β-radiation induces oxidative stress in L. minor.

  15. Modulation of antioxidant enzymes as radioprotector mechanism of oligo elements and lachesis muta in normal tissues; Modulacion de enzimas antioxidantes como mecanismo radioprotector de oligoelementos y lachesis muta en tejidos normales

    Energy Technology Data Exchange (ETDEWEB)

    Crescenti, E.; Croci, M. [Instituto de Inmunooncologia, Cordoba 3200, Buenos Aires (Argentina); Mohamad, N.; Medina, V.; Sambuco, L.; Gutierrez, A.; Nunez, M.; Martin, G.; Cricco, G.; Bergoc, R.; Rivera, E. [Laboratorio de Radioisotopos, Facultad de Farmacia y Bioquimica, Universidad de Buenos Aires. Junin 956. Buenos Aires, (Argentina)]. e-mail: crescentilab@fibertel.com.ar

    2006-07-01

    The therapeutic use of the ionizing radiations (IR) it has acquired great relevance in the last decades although their effects are not selective and they are also manifested on the normal tissues. In previous works we demonstrate the radioprotector effect that the combination of oligo elements Zinc, Selenium and Manganese associated to the snake poison Lachesis muta (O-LM) it exercises on the small intestine and the bone marrow of irradiated mouse. The objective of this work was to study the molecular mechanisms, and particularly the paper of the anti-oxidant superoxide dismutases enzymes (MnSOD and Cu/ZnSOD), Catalase (CAT), and Glutathione Peroxidase (GPx), in the radioprotector action that exercises the combination O-LM. Four groups of mice were used: A) control; B) treated with O-LM; C) irradiated; D) irradiated and treated with O-LM. The two treated groups were injected daily via s.c. with 0,1 ml of O-LM from 30 days before the irradiation and until to 4 days later. The two irradiated groups received 10 Gy in whole body the day 30. The day 35 all the animals were sacrificed. The histological intestinal cuts of the mucous one were evaluated by tint with hematoxyline-eosin; the presence of apoptotic cells it was determined by the Tunel method (Apoptag kit); the expression of PCNA (nuclear antigen of proliferating cells), MnSOD, CuZnSOD, CAT and GPx, by immunohistochemistry. The results demonstrated that in the lot D it was preserved totally the histology of the intestinal mucous. In the control A it was observed PCNA expression in the crypts, of MnSOD in the hairiness and CuZnSOD, CAT and Gpx in both. The change produced by O-LM (group B) it was the increase of PCNA, of CAT and the appearance of MnSOD in the crypts. On the other hand, the irradiation (C) it produced a marked descent in the GPx, the complete disappearance of PCNA and an increase of the apoptotic cells. The group D showed that O-LM it reverted totally the effect of the RI on the expression of PCNA

  16. Copper-induced oxidative stress and responses of antioxidants and phytochelatins in Hydrilla verticillata (L.f.) Royle.

    Science.gov (United States)

    Srivastava, Sudhakar; Mishra, Seema; Tripathi, Rudra D; Dwivedi, Sanjay; Gupta, Dharmendra K

    2006-12-30

    Copper, though essential, is potentially toxic heavy metal at supraoptimal level and has widespread contamination. The present investigation was carried out to study the responses induced by lower as well as higher doses of copper (0.1-25 microM) in an aquatic macrophyte, Hydrilla verticillata (L.f.) Royle for a period of 1-7 days. The plants accumulated copper in high amount with a maximum of 770 microg g(-1) dw on day 7 at 25 microM. Biomass and photosynthetic pigments showed less alteration up to 1 microM while at higher concentrations, significant decline occurred. Malondialdehyde (MDA) content and electrical conductivity (EC) also showed sharp increase at higher concentrations indicating oxidative stress. In response to copper exposure, plants showed significant induction of proteins and enzymes like superoxide dismutase (SOD), ascorbate peroxidase (APX), guaiacol peroxidase (GPX), catalase (CAT) and glutathione reductase (GR), however, only up to moderate exposures. Total non-protein thiols (NP-SH) and cysteine levels increased significantly up to 5 microM copper exposure while at 25 microM, their level declined drastically. Reduced glutathione (GSH) showed decrease at all concentrations while oxidized glutathione (GSSG) simultaneously increased. Phytochelatins (PCs) were also induced significantly at studied concentrations of 1 and 5 microM on day 4 in comparison to control. However, copper chelation depicted by PC-SH to copper ratio was found to be low (6.5% at 1 microM and 2.4% at 5 microM) suggesting that PCs play only a part in integrated mechanisms of copper homeostasis and detoxification. Tolerant response of plants to moderate copper exposures and high accumulation potential warrants their suitability for remediation of moderately copper polluted water bodies.

  17. Responsibility of non-stomatal limitations for the reduction of photosynthesis-response of photosynthesis and antioxidant enzyme characteristics in alfalfa (Medicago sativa L.) seedlings to water stress and rehydration

    Institute of Scientific and Technical Information of China (English)

    LI Wenrao; ZHANG Suiqi; SHAN Lun

    2007-01-01

    Water stress by polyethylene glycol (PEG)-6000 solution (Ψs=0.2 MPa,stress time:48 h,rehydration time:48 h) was performed in leaves of two alfalfa cultivar (Long-Dong and Algonquin) seedlings.Gas exchange parameters,chlorophyll fluorescence parameters,activity of antioxidant enzyme and photosynthetic pigment concentrations were measured to investigate the available photosynthetic and antioxidant enzyme response to variable water conditions as well as stomatal and non-stomatal limitations to photosynthesis.The results showed that non-stomatal limitations were responsible for the reduction of photosynthesis during water stress.At the beginning of water stress (12 h),water was lost and then the stomata closed rapidly,which resulted in a decrease of transpiration,net photosynthesis and CO2 diffusion.Therefore,when intercellular CO2 concentration and carboxylation efficiency decrease,water use efficiency and value of stomatal limitation would increase.However,the decline of net photosynthetic rate was faster than transpiration rate.At the same time,the maximal photochemical efficiency,potential activity of PSII reaction center and photochemical quenching of chlorophyll fluorescence declined significantly,the activity of antioxidant enzyme increased rapidly and the photosynthetic pigment concentrations changed slightly.The results also indicated that,at the initial period of stress,neither oxidative stress nor membrane lipid peroxidation was induced,nor were photosynthetic structures damaged,but photosynthetic functions were partly inhibited.Therefore,the stomatal limitation and non-stomatal limitations had the same responsibility for the reduction of photosynthesis.At the mid-late stage of water stress,net photosynthetic rate,stomatal conductance,maximal photochemical efficiency,potential activity of PSII reaction center and photochemical quenching of chlorophyll fluorescence decreased linearly with the decline of the relative water content.And the relative electron

  18. Genotypic differences in photosynthetic performance, antioxidant capacity, ultrastructure and nutrients in response to combined stress of salinity and Cd in cotton.

    Science.gov (United States)

    Ibrahim, Wasim; Ahmed, Imrul Mosaddek; Chen, Xianhong; Cao, Fangbin; Zhu, Shuijin; Wu, Feibo

    2015-12-01

    Combined stress of salinity and heavy metal is a serious problem for crop production; however, physiological mechanisms of tolerance to such condition remain elusive in cotton. Here, we used two cotton genotypes differing in salt tolerance, to understand their response to salinity (NaCl) and cadmium (Cd) either alone or in combination (Cd + Na) via hydroponics. Results showed that salinity and/or Cd drastically reduced plant growth, chlorophyll content and photosynthesis, with greater effect observed in Zhongmian 41 (sensitive) than Zhong 9806 (tolerant). Although salinity and/or Cd induced malondialdehyde (MDA) accumulation in Zhongmian 41 at 5 and 10 days after treatment, MDA content remained unchanged in Zhong 9806, implying that Zhongmian 41 but not Zhong 9806 faced oxidative stress following exposure to salinity and/or Cd. Differential responses of antioxidant enzymes such as superoxide dismutase, guaiacol peroxidase, catalase and ascorbate peroxidase to Cd, NaCl and Cd + Na indicate genotype- and time course- dependent variations. In both genotypes, Cd content was decreased while Na concentration was increased under combined stress compared with Cd alone. Importantly, NaCl addition in Cd-containing medium caused remarkable reduction in Cd concentration, with the extent of reduction being also dependent on genotypes. The salt-tolerant genotypes had lower Na concentration than sensitive ones. Furthermore, obvious changes in leaf and root ultrastructure was observed under Cd, Na and Cd + Na stress, however Zhong 9806 was less affected compared with Zhongmian 41. These results may provide novel insight into the physiological mechanisms of Cd + Na stress tolerance in various cotton genotypes. PMID:26525977

  19. Genotypic differences in photosynthetic performance, antioxidant capacity, ultrastructure and nutrients in response to combined stress of salinity and Cd in cotton.

    Science.gov (United States)

    Ibrahim, Wasim; Ahmed, Imrul Mosaddek; Chen, Xianhong; Cao, Fangbin; Zhu, Shuijin; Wu, Feibo

    2015-12-01

    Combined stress of salinity and heavy metal is a serious problem for crop production; however, physiological mechanisms of tolerance to such condition remain elusive in cotton. Here, we used two cotton genotypes differing in salt tolerance, to understand their response to salinity (NaCl) and cadmium (Cd) either alone or in combination (Cd + Na) via hydroponics. Results showed that salinity and/or Cd drastically reduced plant growth, chlorophyll content and photosynthesis, with greater effect observed in Zhongmian 41 (sensitive) than Zhong 9806 (tolerant). Although salinity and/or Cd induced malondialdehyde (MDA) accumulation in Zhongmian 41 at 5 and 10 days after treatment, MDA content remained unchanged in Zhong 9806, implying that Zhongmian 41 but not Zhong 9806 faced oxidative stress following exposure to salinity and/or Cd. Differential responses of antioxidant enzymes such as superoxide dismutase, guaiacol peroxidase, catalase and ascorbate peroxidase to Cd, NaCl and Cd + Na indicate genotype- and time course- dependent variations. In both genotypes, Cd content was decreased while Na concentration was increased under combined stress compared with Cd alone. Importantly, NaCl addition in Cd-containing medium caused remarkable reduction in Cd concentration, with the extent of reduction being also dependent on genotypes. The salt-tolerant genotypes had lower Na concentration than sensitive ones. Furthermore, obvious changes in leaf and root ultrastructure was observed under Cd, Na and Cd + Na stress, however Zhong 9806 was less affected compared with Zhongmian 41. These results may provide novel insight into the physiological mechanisms of Cd + Na stress tolerance in various cotton genotypes.

  20. Natural antioxidants in meat and poultry products.

    Science.gov (United States)

    Karre, Liz; Lopez, Keyla; Getty, Kelly J K

    2013-06-01

    In response to recent claims that synthetic antioxidants have the potential to cause toxicological effects and consumers' increased interest in purchasing natural products, the meat and poultry industry has been seeking sources of natural antioxidants. Due to their high phenolic compound content, fruits and other plant materials provide a good alternative to conventional antioxidants. Plum, grape seed extract, cranberry, pomegranate, bearberry, pine bark extract, rosemary, oregano, and other spices functions as antioxidants in meat and poultry products. Pomegranate, pine bark extract, cinnamon, and cloves have exhibited stronger antioxidant properties than some synthetic options. Plum products, grape seed extract, pine bark extract, rosemary, and some spices all have been shown to affect the color of finished meat or poultry products; however, in some products such as pork sausage or uncured meats, an increase in red color may be desired. When selecting a natural antioxidant, sensory and quality impact on the product should be considered to achieve desired traits. PMID:23501254

  1. Primary Metabolism, Phenylpropanoids and Antioxidant Pathways Are Regulated in Potato as a Response to Potato virus Y Infection.

    Directory of Open Access Journals (Sweden)

    Polona Kogovšek

    Full Text Available Potato production is one of the most important agricultural sectors, and it is challenged by various detrimental factors, including virus infections. To control losses in potato production, knowledge about the virus-plant interactions is crucial. Here, we investigated the molecular processes in potato plants as a result of Potato virus Y (PVY infection, the most economically important potato viral pathogen. We performed an integrative study that links changes in the metabolome and gene expression in potato leaves inoculated with the mild PVYN and aggressive PVYNTN isolates, for different times through disease development. At the beginning of infection (1 day post-inoculation, virus-infected plants showed an initial decrease in the concentrations of metabolites connected to sugar and amino-acid metabolism, the TCA cycle, the GABA shunt, ROS scavangers, and phenylpropanoids, relative to the control plants. A pronounced increase in those metabolites was detected at the start of the strong viral multiplication in infected leaves. The alterations in these metabolic pathways were also seen at the gene expression level, as analysed by quantitative PCR. In addition, the systemic response in the metabolome to PVY infection was analysed. Systemic leaves showed a less-pronounced response with fewer metabolites altered, while phenylpropanoid-associated metabolites were strongly accumulated. There was a more rapid onset of accumulation of ROS scavengers in leaves inoculated with PVYN than those inoculated with PVYNTN. This appears to be related to the lower damage observed for leaves of potato infected with the milder PVYN strain, and at least partially explains the differences between the phenotypes observed.

  2. Primary Metabolism, Phenylpropanoids and Antioxidant Pathways Are Regulated in Potato as a Response to Potato virus Y Infection.

    Science.gov (United States)

    Kogovšek, Polona; Pompe-Novak, Maruša; Petek, Marko; Fragner, Lena; Weckwerth, Wolfram; Gruden, Kristina

    2016-01-01

    Potato production is one of the most important agricultural sectors, and it is challenged by various detrimental factors, including virus infections. To control losses in potato production, knowledge about the virus-plant interactions is crucial. Here, we investigated the molecular processes in potato plants as a result of Potato virus Y (PVY) infection, the most economically important potato viral pathogen. We performed an integrative study that links changes in the metabolome and gene expression in potato leaves inoculated with the mild PVYN and aggressive PVYNTN isolates, for different times through disease development. At the beginning of infection (1 day post-inoculation), virus-infected plants showed an initial decrease in the concentrations of metabolites connected to sugar and amino-acid metabolism, the TCA cycle, the GABA shunt, ROS scavangers, and phenylpropanoids, relative to the control plants. A pronounced increase in those metabolites was detected at the start of the strong viral multiplication in infected leaves. The alterations in these metabolic pathways were also seen at the gene expression level, as analysed by quantitative PCR. In addition, the systemic response in the metabolome to PVY infection was analysed. Systemic leaves showed a less-pronounced response with fewer metabolites altered, while phenylpropanoid-associated metabolites were strongly accumulated. There was a more rapid onset of accumulation of ROS scavengers in leaves inoculated with PVYN than those inoculated with PVYNTN. This appears to be related to the lower damage observed for leaves of potato infected with the milder PVYN strain, and at least partially explains the differences between the phenotypes observed. PMID:26727123

  3. The Dynamic Response of an Euler-Bernoulli Beam on an Elastic Foundation by Finite Element Analysis using the Exact Stiffness Matrix

    Science.gov (United States)

    Kim, Jeong Soo; Kyum Kim, Moon

    2012-08-01

    In this study, finite element analysis of beam on elastic foundation, which received great attention of researchers due to its wide applications in engineering, is performed for estimating dynamic responses of shallow foundation using exact stiffness matrix. First, element stiffness matrix based on the closed solution of beam on elastic foundation is derived. Then, we performed static finite element analysis included exact stiffness matrix numerically, comparing results from the analysis with some exact analysis solutions well known for verification. Finally, dynamic finite element analysis is performed for a shallow foundation structure under rectangular pulse loading using trapezoidal method. The dynamic analysis results exist in the reasonable range comparing solution of single degree of freedom problem under a similar condition. The results show that finite element analysis using exact stiffness matrix is evaluated as a good tool of estimating the dynamic response of structures on elastic foundation.

  4. Explicit Finite Element Analysis of Dynamic Response of Protection Frame System Subjected to Impact Loading

    Directory of Open Access Journals (Sweden)

    Fan-Bo Meng

    2013-10-01

    Full Text Available Height limit protection frame of railway bridges apply to the road crossing the railway bridge, its role is to ensure the safety of the railway bridge to prevent road motor vehicles to hit the bridge beam, causing beam damage and even endangering the safety of the railway lines. Therefore, it is necessary to do in-depth discussion of collision mechanism and failure mode of height limit protection frame of railway bridges under the impact of the over-high vehicle, in order to improve the survivability of protection frame to protect the safety of the railway bridge and rail transport. Some rules and characteristics were obtained by establishing collision model of height limit protection frame of railway bridges and the over-high vehicles using the software of ANSYS/LS-DYNA and studying the dynamic response of protection frame impact loading by the vehicle under the different parameters. Thus for the similar protection frame structure design, maintenance and damage assessment provide theoretical support.

  5. Different postprandial acute response in healthy subjects to three strawberry jams varying in carbohydrate and antioxidant content: a randomized, crossover trial

    OpenAIRE

    Martinez, J. A.; Zulet, M.A. (María Ángeles); I. Abete; S. Navas-Carretero; Cuervo, M.; Ibero-Baraibar, I. (Idoia)

    2013-01-01

    PURPOSE: Dietary food composition influences postprandial glucose homeostasis. Thus, the objective was to investigate the effects of an acute intake of three different types of strawberry jam, differing in carbohydrate and antioxidants content, on postprandial glucose metabolism, lipid profile, antioxidant status, and satiety. METHODS: Sixteen healthy adults participated in a randomized, crossover, double-blind study with three arms, receiving 60 g of three different strawberry jam...

  6. Validation of Shoulder Response of Human Body Finite-Element Model (GHBMC) Under Whole Body Lateral Impact Condition.

    Science.gov (United States)

    Park, Gwansik; Kim, Taewung; Panzer, Matthew B; Crandall, Jeff R

    2016-08-01

    In previous shoulder impact studies, the 50th-percentile male GHBMC human body finite-element model was shown to have good biofidelity regarding impact force, but under-predicted shoulder deflection by 80% compared to those observed in the experiment. The goal of this study was to validate the response of the GHBMC M50 model by focusing on three-dimensional shoulder kinematics under a whole-body lateral impact condition. Five modifications, focused on material properties and modeling techniques, were introduced into the model and a supplementary sensitivity analysis was done to determine the influence of each modification to the biomechanical response of the body. The modified model predicted substantially improved shoulder response and peak shoulder deflection within 10% of the observed experimental data, and showed good correlation in the scapula kinematics on sagittal and transverse planes. The improvement in the biofidelity of the shoulder region was mainly due to the modifications of material properties of muscle, the acromioclavicular joint, and the attachment region between the pectoralis major and ribs. Predictions of rib fracture and chest deflection were also improved because of these modifications. PMID:26753830

  7. Assessment of tick antioxidant responses to exogenous oxidative stressors and insight into the role of catalase in the reproductive fitness of the Gulf Coast tick, Amblyomma maculatum.

    Science.gov (United States)

    Kumar, D; Budachetri, K; Meyers, V C; Karim, S

    2016-06-01

    As obligate blood-sucking ectoparasites, to avoid tissue damage, ticks must neutralize the reactive oxygen species (ROS) generated from uptake and digestion of a bloodmeal. Consequently, ticks utilize a battery of antioxidant molecules, including catalase (CAT), an enzyme that converts hydrogen peroxide (H2 O2 ) into water and oxygen. Here, we investigated the tick antioxidant machinery by exogenous injection of sublethal doses of H2 O2 or paraquat. The relative transcript levels of selected Amblyomma maculatum antioxidant targets in tissues were determined by quantitative reverse transcriptase PCR following treatment. The results showed 2-16-fold increases in target antioxidant gene transcripts, signifying the ability of Am. maculatum to regulate its antioxidant machinery when exposed to increased ROS levels. Next, RNA interference was used to determine the functional role of CAT in haematophagy, redox homeostasis and reproductive fitness. CAT gene silencing was confirmed by transcript depletion within tick tissues; however, CAT knockdown alone did not interfere with tick haematophagy or phenotype, as confirmed by the resulting differential expression of antioxidant genes, thereby indicating an alternative mechanism for ROS control. Interestingly, double stranded RNA of CAT gene (dsCAT) and the CAT inhibitor, 3-aminotriazole, together reduced tick reproductive fitness via a marked reduction in egg mass and larval eclosion rates, highlighting a role for CAT in tick redox-homeostasis, making it a potential target for tick control. PMID:26919203

  8. Antioxidant Defense Mechanisms in Pseudomonas aeruginosa: Role of Iron-Cofactored Superoxide Dismutase in Response to UV-C Radiations.