Sample records for n-acetylcysteine-mediated catalase upregulation

  1. A rapid and transient ROS generation by cadmium triggers apoptosis via caspase-dependent pathway in HepG2 cells and this is inhibited through N-acetylcysteine-mediated catalase upregulation

    SciTech Connect

    Oh, Seon-Hee [Research Center for Resistant Cells, College of Medicine, Chosun University, Seosuk-dong, Dong-gu, Gwangju 501-759 (Korea, Republic of); Lim, Sung-Chul [Research Center for Resistant Cells, College of Medicine, Chosun University, Seosuk-dong, Dong-gu, Gwangju 501-759 (Korea, Republic of) and Department of Pathology, College of Medicine, Chosun University, Seosuk-dong, Dong-gu, Gwangju 501-759 (Korea, Republic of)]. E-mail: sclim@chosun.ac.kr

    2006-05-01

    Although reactive oxygen species (ROS) have been implicated in cadmium (Cd)-induced hepatotoxicity, the role of ROS in this pathway remains unclear. Therefore, we attempted to determine the molecular mechanisms relevant to Cd-induced cell death in HepG2 cells. Cd was found to induce apoptosis in the HepG2 cells in a time- and dose-dependent fashion, as confirmed by DNA fragmentation analysis and TUNEL staining. In the early stages, both rapid and transient ROS generation triggered apoptosis via Fas activation and subsequent caspase-8-dependent Bid cleavage, as well as by calpain-mediated mitochondrial Bax cleavage. The timing of Bid activation was coincided with the timing at which the mitochondrial transmembrane potential (MMP) collapsed as well as the cytochrome c (Cyt c) released into the cytosol. Furthermore, mitochondrial permeability transition (MPT) pore inhibitors, such as cyclosporin A (CsA) and bongkrekic acid (BA), did not block Cd-induced ROS generation, MMP collapse and Cyt c release. N-acetylcysteine (NAC) pretreatment resulted in the complete inhibition of the Cd-induced apoptosis via catalase upregulation and subsequent Fas downregulation. NAC treatment also completely blocked the Cd-induced intracellular ROS generation, MMP collapse and Cyt c release, indicating that Cd-induced mitochondrial dysfunction may be regulated indirectly by ROS-mediated signaling pathway. Taken together, a rapid and transient ROS generation by Cd triggers apoptosis via caspase-dependent pathway and subsequent mitochondrial pathway. NAC inhibits Cd-induced apoptosis through the blocking of ROS generation as well as the catalase upregulation.

  2. Hydroxytyrosol reduces intracellular reactive oxygen species levels in vascular endothelial cells by upregulating catalase expression through the AMPK-FOXO3a pathway.

    PubMed

    Zrelli, Houda; Matsuoka, Mieko; Kitazaki, Shiho; Zarrouk, Mokhtar; Miyazaki, Hitoshi

    2011-06-25

    Reactive oxygen species are critically involved in the endothelial dysfunction that contributes to atherosclerosis development. Hydroxytyrosol (HT), a main phenolic compound in olive oil and leaves from Olea europaea L., has antiatherogenic properties with powerful antioxidant activity. The present study verifies the antioxidant activity of HT on H2O2-induced intracellular reactive oxygen species in porcine pulmonary artery endothelial cells (VECs) and the involved molecular mechanisms. Incubation of VECs with HT prevented the increase in intracellular reactive oxygen species levels in the presence of H2O2. HT increased catalase mRNA, protein and activity. Catalase siRNA suppressed HT-dependent reduction of intracellular reactive oxygen species. HT increased both cytosolic and nuclear protein levels of forkhead transcription factor 3a (FOXO3a), as well as the phosphorylation of AMP-activated protein kinase (AMPK) that translocates FOXO3a to the nucleus. AMPK siRNA and a specific inhibitor suppressed HT-induced FOXO3a upregulation and catalase expression. Moreover, FOXO3a siRNA blocked HT-dependent increase in catalase expression. Taken together, our findings strongly demonstrate that HT positively regulates the antioxidant defense system in VECs by inducing the phosphorylation of AMPK with subsequent activation of FOXO3a and catalase expression, and provides a molecular basis for the prevention of cardiovascular diseases by HT. PMID:21497591

  3. Bentonite-supported catalase

    Microsoft Academic Search

    S. Alkan; H. Ceylan; O. Arslan

    2005-01-01

    The properties of the clay bentonite as a support for enzyme immobilization were studied using the enzyme catalase. Such an immobilization does not result in en- zyme inactivation and constitutes a valuable method for immobilizing catalase at high ionic strength. The bentonite-supported catalase was characterized in terms of pH and ionic strength dependencies, thermal and storage stability and kinetic parameters.

  4. Catalase Test Protocol

    NSDL National Science Digital Library

    American Society For Microbiology

    2010-11-11

    The catalase test is used to detect the presence of the enzyme catalase in bacteria. Catalase serves to neutralize the bactericidal effects of hydrogen peroxide. Its concentration in bacteria has been correlated with pathogenicity. This enzymatic test is essential in the scheme of identification for gram-positive organisms and certain gram-negative organisms. It is a primary test used in the differentiation of staphylococci and streptococci.

  5. Regulation of Brucella abortus Catalase

    PubMed Central

    Kim, Jeong-a; Sha, Zengyu; Mayfield, John E.

    2000-01-01

    All aerobic organisms have mechanisms that protect against oxidative compounds. Catalase, peroxidase, superoxide dismutase, glutathione, and thioredoxin are widely distributed in many taxa and constitute elements of a nearly ubiquitous antioxidant metabolic strategy. Interestingly, the regulatory mechanisms that control these elements are rather different depending on the nature of the oxidative stress and the organism. Catalase is well documented to play an important role in protecting cells from oxidative stress. In particular, pathogenic bacteria seem to use this enzyme as a defensive tool against attack by the host. To investigate the significance of catalase in hostile environments, we made catalase deletion mutations in two different B. abortus strains and used two-dimensional gel analysis, survival tests, and adaptation experiments to explore the behavior and role of catalase under several oxidative stress conditions. These studies show that B. abortus strains that do not express catalase activity exhibit increased sensitivity to hydrogen peroxide. We also demonstrate that catalase expression is regulated in this species, and that preexposure to a sublethal concentration of hydrogen peroxide allows B. abortus to adapt so as to survive subsequent exposure to higher concentrations of hydrogen peroxide. PMID:10858195

  6. High Dietary Fat Selectively Increases Catalase Expression within Cardiac Mitochondria*

    PubMed Central

    Rindler, Paul M.; Plafker, Scott M.; Szweda, Luke I.; Kinter, Michael

    2013-01-01

    Obesity is a predictor of diabetes and cardiovascular disease. One consequence of obesity is dyslipidemia characterized by high blood triglycerides. It has been proposed that oxidative stress, driven by utilization of lipids for energy, contributes to these diseases. The effects of oxidative stress are mitigated by an endogenous antioxidant enzyme network, but little is known about its response to high fat utilization. Our experiments used a multiplexed quantitative proteomics method to measure antioxidant enzyme expression in heart tissue in a mouse model of diet-induced obesity. This experiment showed a rapid and specific up-regulation of catalase protein, with subsequent assays showing increases in activity and mRNA. Catalase, traditionally considered a peroxisomal protein, was found to be present in cardiac mitochondria and significantly increased in content and activity during high fat feeding. These data, coupled with the fact that fatty acid oxidation enhances mitochondrial H2O2 production, suggest that a localized catalase increase is needed to consume excessive mitochondrial H2O2 produced by increased fat metabolism. To determine whether the catalase-specific response is a common feature of physiological conditions that increase blood triglycerides and fatty acid oxidation, we measured changes in antioxidant expression in fasted versus fed mice. Indeed, a similar specific catalase increase was observed in mice fasted for 24 h. Our findings suggest a fundamental metabolic process in which catalase expression is regulated to prevent damage while preserving an H2O2-mediated sensing of diet composition that appropriately adjusts insulin sensitivity in the short term as needed to prioritize lipid metabolism for complete utilization. PMID:23204527

  7. 7 CFR 58.432 - Catalase.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ...PRODUCTS 1 General Specifications for Dairy Plants Approved for USDA Inspection and Grading Service 1 Quality Specifications for Raw Material § 58.432 Catalase. The catalase preparation shall be a stable, buffered solution, neutral in pH, having...

  8. 7 CFR 58.432 - Catalase.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ...Grading Service 1 Quality Specifications for Raw Material § 58.432 Catalase. The catalase preparation shall be a stable, buffered solution, neutral in pH, having a potency of not less than 100 Keil units per milliliter. The source...

  9. Catalase activity and innate immune response of Caenorhabditis elegans against the heavy metal toxin lead.

    PubMed

    Vigneshkumar, Balasubramanian; Pandian, Shunmugiah Karutha; Balamurugan, Krishnaswamy

    2013-06-01

    The heavy metal lead-induced oxidative stress on Caenorhabditis elegans was examined at the level of catalase activity and on innate immunity. Stress-induced C. elegans was exposed to Pseudomonas aeruginosa PA14::GFP for monitoring the impact at the physiological level. Role of catalase on the innate-immune responses of C. elegans was examined. PA14::GFP did not colonize lead pretreated C. elegans intestinal cells significantly compared to untreated controls, indicating stress-mediated upregulation of host-immunity. Semiquantitative PCR analyses of lead-exposed and PA14-infected C. elegans mRNA showed significant upregulation of candidate antimicrobial enzyme gene lys-7 after 24 h of exposures. Upregulation of metallothionein(mtl-1) when compared to mtl-2 in response to the lead suggesting active detoxification of metal by mtl-1. Exogenously provided Catalase (0.4-3.2 U) induced significant upregulation of lys-7 compared to controls. lys-7 upregulation during lead exposure was reconfirmed by real-time PCR. Confocal microscopy and fluorescence spectrophotometer analyses indicated that the lead pretreated C. elegans was significantly less colonized by PA14::GFP when compared to controls. Relative expression of ctl-1 and ctl-2 mRNA was measured using real time PCR and found to be regulated during lead exposures. Over all, the upregulation of antimicrobial gene expression appears to be correlated with the level of catalase during stress emphasizing their key roles in defensive mechanism(s). These results provide a link between the stress and related immune responses which can be explored in higher systems. PMID:21656642

  10. Sirt1 protects against oxidative stress-induced renal tubular cell apoptosis by the bidirectional regulation of catalase expression

    SciTech Connect

    Hasegawa, Kazuhiro [Department of Internal Medicine, Keio University, 35 Shinanomachi, Shinjuku-ku, Tokyo 1608582 (Japan); Wakino, Shu [Department of Internal Medicine, Keio University, 35 Shinanomachi, Shinjuku-ku, Tokyo 1608582 (Japan)], E-mail: swakino@sc.itc.keio.ac.jp; Yoshioka, Kyoko; Tatematsu, Satoru; Hara, Yoshikazu; Minakuchi, Hitoshi; Washida, Naoki; Tokuyama, Hirobumi; Hayashi, Koichi; Itoh, Hiroshi [Department of Internal Medicine, Keio University, 35 Shinanomachi, Shinjuku-ku, Tokyo 1608582 (Japan)

    2008-07-18

    NAD{sup +}-dependent protein deacetylase Sirt1 regulates cellular apoptosis. We examined the role of Sirt1 in renal tubular cell apoptosis by using HK-2 cells, proximal tubular cell lines with or without reactive oxygen species (ROS), H{sub 2}O{sub 2}. Without any ROS, Sirt1 inhibitors enhanced apoptosis and the expression of ROS scavenger, catalase, and Sirt1 overexpression downregulated catalase. When apoptosis was induced with H{sub 2}O{sub 2}, Sirt1 was upregulated with the concomitant increase in catalase expression. Sirt1 overexpression rescued H{sub 2}O{sub 2}-induced apoptosis through the upregulation of catalase. H{sub 2}O{sub 2} induced the nuclear accumulation of forkhead transcription factor, FoxO3a and the gene silencing of FoxO3a enhanced H{sub 2}O{sub 2}-induced apoptosis. In conclusion, endogenous Sirt1 maintains cell survival by regulating catalase expression and by preventing the depletion of ROS required for cell survival. In contrast, excess ROS upregulates Sirt1, which activates FoxO3a and catalase leading to rescuing apoptosis. Thus, Sirt1 constitutes a determinant of renal tubular cell apoptosis by regulating cellular ROS levels.

  11. Thirty years of heme catalases structural biology.

    PubMed

    Díaz, Adelaida; Loewen, Peter C; Fita, Ignacio; Carpena, Xavi

    2012-09-15

    About thirty years ago the crystal structures of the heme catalases from Penicillium vitale (PVC) and, a few months later, from bovine liver (BLC) were published. Both enzymes were compact tetrameric molecules with subunits that, despite their size differences and the large phylogenetic separation between the two organisms, presented a striking structural similarity for about 460 residues. The high conservation, confirmed in all the subsequent structures determined, suggested a strong pressure to preserve a functional catalase fold, which is almost exclusively found in these mono-functional heme catalases. However, even in the absence of the catalase fold an efficient catalase activity is also found in the heme containing catalase-peroxidase proteins. The structure of these broad substrate range enzymes, reported for the first time less than ten years ago from the halophilic archaebacterium Haloarcula marismortui (HmCPx) and from the bacterium Burkholderia pseudomallei (BpKatG), showed a heme pocket closely related to that of plant peroxidases, though with a number of unique modifications that enable the catalase reaction. Despite the wealth of structural information already available, for both monofunctional catalases and catalase-peroxidases, a number of unanswered major questions require continuing structural research with truly innovative approaches. PMID:22209752

  12. Catalase and NO CATALASE ACTIVITY1 Promote Autophagy-Dependent Cell Death in ArabidopsisC W OPEN

    E-print Network

    Schierup, Mikkel Heide

    Catalase and NO CATALASE ACTIVITY1 Promote Autophagy-Dependent Cell Death in ArabidopsisC W OPEN be detoxified by antioxidative enzymes, including catalases. We previously isolated catalase-deficient mutants triggered by the bacterial effector avrRpm1. To test if catalase deficiency likewise affected both

  13. Characterization of Catalase from Psychrotolerant Psychrobacter piscatorii T-3 Exhibiting High Catalase Activity

    PubMed Central

    Kimoto, Hideyuki; Yoshimune, Kazuaki; Matsuyma, Hidetoshi; Yumoto, Isao

    2012-01-01

    A psychrotolerant bacterium, strain T-3 (identified as Psychrobacter piscatorii), that exhibited an extraordinarily high catalase activity was isolated from the drain pool of a plant that uses H2O2 as a bleaching agent. Its cell extract exhibited a catalase activity (19,700 U·mg protein?1) that was higher than that of Micrococcus luteus used for industrial catalase production. Catalase was approximately 10% of the total proteins in the cell extract of the strain. The catalase (PktA) was purified homogeneously by only two purification steps, anion exchange and hydrophobic chromatographies. The purified catalase exhibited higher catalytic efficiency and higher sensitivity of activity at high temperatures than M. luteus catalase. The deduced amino acid sequence showed the highest homology with catalase of Psycrobacter cryohalolentis, a psychrotolelant bacterium obtained from Siberian permafrost. These findings suggest that the characteristics of the PktA molecule reflected the taxonomic relationship of the isolate as well as the environmental conditions (low temperatures and high concentrations of H2O2) under which the bacterium survives. Strain T-3 efficiently produces a catalase (PktA) at a higher rate than Exiguobacterium oxidotolerans, which produces a very strong activity of catalase (EktA) at a moderate rate, in order to adapt to high concentration of H2O2. PMID:22408420

  14. Catalases Induction in High Virulence Pinewood Nematode Bursaphelenchus xylophilus under Hydrogen Peroxide-Induced Stress

    PubMed Central

    Vicente, Cláudia S. L.; Ikuyo, Yoriko; Shinya, Ryoji; Mota, Manuel; Hasegawa, Koichi

    2015-01-01

    Considered an EPPO A2 quarantine pest, Bursaphelenchus xylophilus is the causal agent of the pine wilt disease and the most devastating plant parasitic nematode attacking coniferous trees in the world. In the early stages of invasion, this nematode has to manage host defence mechanisms, such as strong oxidative stress. Only successful, virulent nematodes are able to tolerate the basal plant defences, and furthermore migrate and proliferate inside of the host tree. In this work, our main objective was to understand to what extent B. xylophilus catalases are involved in their tolerance to oxidative stress and virulence, using as oxidant agent the reactive oxygen species hydrogen peroxide (H2O2). After 24 hours of exposure, high virulence isolates of B. xylophilus could withstand higher H2O2 concentrations in comparison with low virulence B. xylophilus and B. mucronatus, corroborating our observation of Bxy-ctl-1 and Bxy-ctl-2 catalase up-regulation under the same experimental conditions. Both catalases are expressed throughout the nematode intestine. In addition, transgenic strains of Caenorhabditis elegans overexpressing B. xylophilus catalases were constructed and evaluated for survival under similar conditions as previously. Our results suggest that catalases of high virulence B. xylophilus were crucial for nematode survival under prolonged exposure to in vitro oxidative stress, highlighting their adaptive response, which could contribute to their success in host conditions. PMID:25894519

  15. Protection of Bacillus pumilus Spores by Catalases

    PubMed Central

    Checinska, Aleksandra; Burbank, Malcolm

    2012-01-01

    Bacillus pumilus SAFR-032, isolated at spacecraft assembly facilities of the National Aeronautics and Space Administration Jet Propulsion Laboratory, is difficult to kill by the sterilization method of choice, which uses liquid or vapor hydrogen peroxide. We identified two manganese catalases, YjqC and BPUM_1305, in spore protein extracts of several B. pumilus strains by using PAGE and mass spectrometric analyses. While the BPUM_1305 catalase was present in six of the B. pumilus strains tested, YjqC was not detected in ATCC 7061 and BG-B79. Furthermore, both catalases were localized in the spore coat layer along with laccase and superoxide dismutase. Although the initial catalase activity in ATCC 7061 spores was higher, it was less stable over time than the SAFR-032 enzyme. We propose that synergistic activity of YjqC and BPUM_1305, along with other coat oxidoreductases, contributes to the enhanced resistance of B. pumilus spores to hydrogen peroxide. We observed that the product of the catalase reaction, gaseous oxygen, forms expanding vesicles on the spore surface, affecting the mechanical integrity of the coat layer, resulting in aggregation of the spores. The accumulation of oxygen gas and aggregations may play a crucial role in limiting further exposure of Bacilli spore surfaces to hydrogen peroxide or other toxic chemicals when water is present. PMID:22752169

  16. Catalase degrades diperoxovanadate and releases oxygen.

    PubMed

    Ravishankar, H N; Rao, A V; Ramasarma, T

    1995-08-20

    On incubation with catalase diperoxovanadate was found to be degraded, showing a decrease in its absorbance at 356 nm and a loss of its peak with a chemical shift at -706 ppm in its 51V NMR spectrum. The products of the reaction had an absorption peak at 266 nm and chemical shifts at -569 and -578 ppm in NMR spectra assigned to dimer and tetramer of vanadate, respectively. Catalase released half the molecular equivalent of oxygen during this degradation of diperoxovanadate with a rate two orders of magnitude lower than that seen with H2O2. By substituting for and not releasing H2O2, diperoxovanadate supported scopoletin oxidation by horseradish peroxidase, as indicated by the reaction being not sensitive to catalase, unlike that seen with H2O2. Catalase-dependent oxygen release was sensitive to azide with both H2O2 and diperoxovanadate as substrates, whereas EDTA selectively inhibited this reaction with diperoxovanadate. The results bring out the potential of catalase in degrading diperoxovanadate and suggest caution in the use of this enzyme to destroy excess H2O2 during preparation of this compound. PMID:7646074

  17. Protection of Bacillus pumilus spores by catalases.

    PubMed

    Checinska, Aleksandra; Burbank, Malcolm; Paszczynski, Andrzej J

    2012-09-01

    Bacillus pumilus SAFR-032, isolated at spacecraft assembly facilities of the National Aeronautics and Space Administration Jet Propulsion Laboratory, is difficult to kill by the sterilization method of choice, which uses liquid or vapor hydrogen peroxide. We identified two manganese catalases, YjqC and BPUM_1305, in spore protein extracts of several B. pumilus strains by using PAGE and mass spectrometric analyses. While the BPUM_1305 catalase was present in six of the B. pumilus strains tested, YjqC was not detected in ATCC 7061 and BG-B79. Furthermore, both catalases were localized in the spore coat layer along with laccase and superoxide dismutase. Although the initial catalase activity in ATCC 7061 spores was higher, it was less stable over time than the SAFR-032 enzyme. We propose that synergistic activity of YjqC and BPUM_1305, along with other coat oxidoreductases, contributes to the enhanced resistance of B. pumilus spores to hydrogen peroxide. We observed that the product of the catalase reaction, gaseous oxygen, forms expanding vesicles on the spore surface, affecting the mechanical integrity of the coat layer, resulting in aggregation of the spores. The accumulation of oxygen gas and aggregations may play a crucial role in limiting further exposure of Bacilli spore surfaces to hydrogen peroxide or other toxic chemicals when water is present. PMID:22752169

  18. Original article Restoring catalase activity in Staphylococcus aureus subsp.

    E-print Network

    Paris-Sud XI, Université de

    Original article Restoring catalase activity in Staphylococcus aureus subsp. anaerobius leads; accepted 15 February 2010) Abstract ­ Staphylococcus aureus subsp. anaerobius, a microaerophilic / pathogenesis / catalase / abscess disease / sheep 1. INTRODUCTION Staphylococcus aureus subsp. anaerobius

  19. 21 CFR 173.135 - Catalase derived from Micrococcus lysodeikticus.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ...CONTINUED) FOOD FOR HUMAN CONSUMPTION (CONTINUED) SECONDARY DIRECT FOOD ADDITIVES PERMITTED IN FOOD FOR HUMAN CONSUMPTION Enzyme Preparations and Microorganisms § 173.135 Catalase derived from Micrococcus lysodeikticus. Bacterial catalase...

  20. 21 CFR 173.135 - Catalase derived from Micrococcus lysodeikticus.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ...CONTINUED) FOOD FOR HUMAN CONSUMPTION (CONTINUED) SECONDARY DIRECT FOOD ADDITIVES PERMITTED IN FOOD FOR HUMAN CONSUMPTION Enzyme Preparations and Microorganisms § 173.135 Catalase derived from Micrococcus lysodeikticus. Bacterial catalase...

  1. 21 CFR 173.135 - Catalase derived from Micrococcus lysodeikticus.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ...CONTINUED) FOOD FOR HUMAN CONSUMPTION (CONTINUED) SECONDARY DIRECT FOOD ADDITIVES PERMITTED IN FOOD FOR HUMAN CONSUMPTION Enzyme Preparations and Microorganisms § 173.135 Catalase derived from Micrococcus lysodeikticus. Bacterial catalase...

  2. 21 CFR 173.135 - Catalase derived from Micrococcus lysodeikticus.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ...CONTINUED) FOOD FOR HUMAN CONSUMPTION (CONTINUED) SECONDARY DIRECT FOOD ADDITIVES PERMITTED IN FOOD FOR HUMAN CONSUMPTION Enzyme Preparations and Microorganisms § 173.135 Catalase derived from Micrococcus lysodeikticus. Bacterial catalase...

  3. 21 CFR 173.135 - Catalase derived from Micrococcus lysodeikticus.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ...DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) SECONDARY DIRECT FOOD ADDITIVES PERMITTED IN FOOD FOR HUMAN CONSUMPTION Enzyme Preparations and Microorganisms § 173.135 Catalase derived from Micrococcus lysodeikticus. Bacterial catalase...

  4. Molecular identification of catalases from Nicotiana plumbaginifolia (L.).

    PubMed

    Willekens, H; Villarroel, R; Van Montagu, M; Inzé, D; Van Camp, W

    1994-09-19

    We have isolated three different catalase cDNAs from Nicotiana plumbaginifolia (cat1, cat2, and cat3) and a partial sequence of a fourth catalase gene (cat4) that shows no discernible expression based on Northern analysis. The catalase sequences were used to determine the similarity with other plant catalases and to study the transcriptional response to paraquat, 3-aminotriazole, and salicylic acid. 3-Aminotriazole induces mRNA levels of cat1, cat2 and cat3, indicating that a reduction in catalase activity positively affects catalase mRNA abundance. Salicylic acid that binds catalase in vitro, had no effect on catalase transcript levels at physiological concentrations. Paraquat resulted in the induction of cat1. PMID:7925949

  5. CMC\\/PDM capsule immobilize catalase

    Microsoft Academic Search

    Wenlong Hou; Zhiwei Zhang; Shaoli Niu; Yuedong Yang; Zhiqing Duan; Xiaomin Liu

    2010-01-01

    The nature of catalase, immobilized in sodium carboxymethyl cellulose (CMC) and poly(n,n-dimethylaminoethyl methacrylate)(PDM), were primarily studied. The results showed that the CMC\\/PDM capsules, which were made by 2.0% of mass concentration of CMC and 25% of mass concentration of PDM, were the smoothest, the hardest, and the most effective. The optimum pH and temperature were 7.0 and 40°C respectively for

  6. Probing the binding of flavonoids to catalase by molecular spectroscopy

    NASA Astrophysics Data System (ADS)

    Zhu, Jingfeng; Zhang, Xia; Li, Daojin; Jin, Jing

    2007-10-01

    The binding of flavonoids (quercetin and myricetin) to catalase was investigated by fluorescence and circular dichroism (CD) techniques under physiological conditions. The binding parameters and binding mode between flavonoids and catalase were determined, and the results of synchronous fluorescence spectra and CD indicated a conformational change of catalase with addition of flavonoids. The effect of both Cu 2+ and vitamin C on the binding constant of flavonoid-catalase was also examined. The experiment data show that the difference of the structure characteristics of quercetin and myricetin has a significant effect on their binding affinity for catalase.

  7. Catalase-positive microbial detection by using different ultrasonic parameters

    NASA Astrophysics Data System (ADS)

    Shukla, S. K.; Durán, C.; Elvira, L.

    2012-12-01

    A method for rapid detection of catalase enzyme activity using ultrasonic parameters is presented in this work. It is based on the detection of the hydrolysis of hydrogen peroxide molecule into water and oxygen induced by the enzyme catalase. A special medium was made to amplify changes produced by catalase enzyme during the hydrolysis process. Enzymatic process can be monitored by means of ultrasonic parameters such as wave amplitude, time of flight (TOF), and backscattering measurements which are sensitive to oxygen bubble production. It is shown that catalase activity of the order of 10-3unit/ml can be detected using different ultrasonic parameters. The sensitivity provided by them is discussed.

  8. Inhibition of catalase activity in vitro by diesel exhaust particles

    SciTech Connect

    Mori, Yoki; Murakami, Sumika; Sagae, Toshiyuki [Health Sciences Univ. of Hokkaido (Japan)] [and others] [Health Sciences Univ. of Hokkaido (Japan); and others

    1996-02-09

    The effect of diesel exhaust particles (DEP) on the activity of catalase, an intracellular anti-oxidant, was investigated because H{sub 2}O{sub 2} is a cytotoxic oxidant, and catalase released from alveolar cells is an important antioxidant in the epithelial lining fluid in the lung. DEP inhibited the activity of bovine liver catalase dose-dependently, to 25-30% of its original value. The inhibition of catalase by DEP was observed only in the presence of anions such as Cl{sup {minus}}, Br{sup {minus}}, or thiocyanate. Other anions, such as CH{sub 3}COO{sup {minus}} or SO{sub 4}{sup {minus}}, and cations such as K{sup +}, Na{sup +}, Mg{sup 2+}, or Fe{sup 2+}, did not affect the activity of catalase, even in the presence of DEP extract. Catalase from guinea pig alveolar cells and catalase from red blood cells were also inhibited by DEP extracts, as was catalase from bovine liver. These results suggest that DEP taken up in the lung and located on alveolar spaces might cause cell injury by inhibiting the activity of catalase in epithelial lining fluid, enhancing the toxicity of H{sub 2}O{sub 2} generated from cells in addition to that of O{sub 2}{sup {minus}} generated by the chemical reaction of DEP with oxygen. 10 refs., 6 figs.

  9. Hydrogen peroxide production regulates the mitochondrial function in insulin resistant muscle cells: effect of catalase overexpression.

    PubMed

    Barbosa, Marina R; Sampaio, Igor H; Teodoro, Bruno G; Sousa, Thais A; Zoppi, Claudio C; Queiroz, André L; Passos, Madla A; Alberici, Luciane C; Teixeira, Felipe R; Manfiolli, Adriana O; Batista, Thiago M; Cappelli, Ana Paula Gameiro; Reis, Rosana I; Frasson, Danúbia; Kettelhut, Isis C; Parreiras-e-Silva, Lucas T; Costa-Neto, Claudio M; Carneiro, Everardo M; Curi, Rui; Silveira, Leonardo R

    2013-10-01

    The mitochondrial redox state plays a central role in the link between mitochondrial overloading and insulin resistance. However, the mechanism by which the ROS induce insulin resistance in skeletal muscle cells is not completely understood. We examined the association between mitochondrial function and H2O2 production in insulin resistant cells. Our hypothesis is that the low mitochondrial oxygen consumption leads to elevated ROS production by a mechanism associated with reduced PGC1? transcription and low content of phosphorylated CREB. The cells were transfected with either the encoded sequence for catalase overexpression or the specific siRNA for catalase inhibition. After transfection, myotubes were incubated with palmitic acid (500?M) and the insulin response, as well as mitochondrial function and fatty acid metabolism, was determined. The low mitochondrial oxygen consumption led to elevated ROS production by a mechanism associated with ?-oxidation of fatty acids. Rotenone was observed to reduce the ratio of ROS production. The elevated H2O2 production markedly decreased the PGC1? transcription, an effect that was accompanied by a reduced phosphorylation of Akt and CREB. The catalase transfection prevented the reduction in the phosphorylated level of Akt and upregulated the levels of phosphorylated CREB. The mitochondrial function was elevated and H2O2 production reduced, thus increasing the insulin sensitivity. The catalase overexpression improved mitochondrial respiration protecting the cells from fatty acid-induced, insulin resistance. This effect indicates that control of hydrogen peroxide production regulates the mitochondrial respiration preventing the insulin resistance in skeletal muscle cells by a mechanism associated with CREB phosphorylation and ?-oxidation of fatty acids. PMID:23643711

  10. Molecular characterization and mRNA expression of catalase from pearl oyster Pinctada fucata.

    PubMed

    Guo, Huayang; Zhang, Dianchang; Cui, Shuge; Chen, Mingqiang; Wu, Kaichang; Li, Youning; Su, Tianfeng; Jiang, Shigui

    2011-12-01

    Catalase (EC 1.11.1.6) is an important antioxidant enzyme that protects aerobic organisms against oxidative damage by degrading hydrogen peroxide to water and oxygen. In the present study, a catalase cDNA of peal oyster Pincatada fucata (designated as PoCAT) is cloned and characterized by expressed sequence tag (EST) and rapid amplification of cDNA ends (RACE) methods. PoCAT is 2428 bp long and consists of a 5'-UTR of 140 bp, an unusually long 3'-UTR of 749 bp, and an open reading frame (ORF) of 1539 bp. The ORF of PoCAT encodes a polypeptide of 512 amino acids with molecular weight of 58.1 kDa and the theoretical isoelectric point of 8.4. PoCAT shares 62.3-82.2% identity and 73.0-92.0% similarity to other catalase amino acid sequences. Sequence alignment indicates that PoCAT contains the proximal heme-ligand signature sequence (R³?¹LFSYSDT³??), the proximal active site signature (F?¹NRERIPERVVHAKGGGA??), and the three catalytic amino acid residues (His?², Asn¹??, and Tyr³??). PoCAT has two potential glycosylation sites (N?³?YS?³? and N???FS???) and a peroxisome targeting signal (ASL). PoCAT mRNA was ubiquitously expressed in all detected tissues, and the expression level of PoCAT mRNA was higher in intestine and mantle. The expression profile analysis showed that the expression level of PoCAT mRNA in intestine was significantly up-regulated at 2, 4 and 12 h after Vibrio alginolyticus stimulation. These results demonstrated that PoCAT is a typical member of catalase family and might be involved in innate immune responses of pearl oyster. PMID:22118636

  11. The Effect of Alcohol and Hydrogen Peroxide on Liver Hepcidin Gene Expression in Mice Lacking Antioxidant Enzymes, Glutathione Peroxidase-1 or Catalase

    PubMed Central

    Harrison-Findik, Duygu Dee; Lu, Sizhao

    2015-01-01

    This study investigates the regulation of hepcidin, the key iron-regulatory molecule, by alcohol and hydrogen peroxide (H2O2) in glutathione peroxidase-1 (gpx-1?/?) and catalase (catalase?/?) knockout mice. For alcohol studies, 10% ethanol was administered in the drinking water for 7 days. Gpx-1?/? displayed significantly higher hepatic H2O2 levels than catalase?/? compared to wild-type mice, as measured by 2'-7'-dichlorodihydrofluorescein diacetate (DCFH-DA). The basal level of liver hepcidin expression was attenuated in gpx-1?/? mice. Alcohol increased H2O2 production in catalase?/? and wild-type, but not gpx-1?/?, mice. Hepcidin expression was inhibited in alcohol-fed catalase?/? and wild-type mice. In contrast, alcohol elevated hepcidin expression in gpx-1?/? mice. Gpx-1?/? mice also displayed higher level of basal liver CHOP protein expression than catalase?/? mice. Alcohol induced CHOP and to a lesser extent GRP78/BiP expression, but not XBP1 splicing or binding of CREBH to hepcidin gene promoter, in gpx-1?/? mice. The up-regulation of hepatic ATF4 mRNA levels, which was observed in gpx-1?/? mice, was attenuated by alcohol. In conclusion, our findings strongly suggest that H2O2 inhibits hepcidin expression in vivo. Synergistic induction of CHOP by alcohol and H2O2, in the absence of gpx-1, stimulates liver hepcidin gene expression by ER stress independent of CREBH. PMID:25955433

  12. Genes Important for Catalase Activity in Enterococcus faecalis

    PubMed Central

    Baureder, Michael; Hederstedt, Lars

    2012-01-01

    Little in general is known about how heme proteins are assembled from their constituents in cells. The Gram-positive bacterium Enterococcus faecalis cannot synthesize heme and does not depend on it for growth. However, when supplied with heme in the growth medium the cells can synthesize two heme proteins; catalase (KatA) and cytochrome bd (CydAB). To identify novel factors important for catalase biogenesis libraries of E. faecalis gene insertion mutants were generated using two different types of transposons. The libraries of mutants were screened for clones deficient in catalase activity using a colony zymogram staining procedure. Analysis of obtained clones identified, in addition to katA (encoding the catalase enzyme protein), nine genes distributed over five different chromosomal loci. No factors with a dedicated essential role in catalase biogenesis or heme trafficking were revealed, but the results indicate the RNA degradosome (srmB, rnjA), an ABC-type oligopeptide transporter (oppBC), a two-component signal transducer (etaR), and NADH peroxidase (npr) as being important for expression of catalase activity in E. faecalis. It is demonstrated that catalase biogenesis in E. faecalis is independent of the CydABCD proteins and that a conserved proline residue in the N-terminal region of KatA is important for catalase assembly. PMID:22590595

  13. IS CATALASE ACTIVITY ASSOCIATED WITH MAIZE RESISTANCE TO ASPERGILLUS FLAVUS

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Catalase activity was measured in various cob tissues during maize ear development because of its role in maintaining reactive oxygen homeostasis during biotic and abiotic stress. Catalase activity was determined in immature and mature embryos, pericarp, and rachis tissues of maize lines that are re...

  14. Upregulation of Opioid Receptors

    Microsoft Academic Search

    Ellen M. Unterwald; Richard D. Howells

    \\u000a It is well established that chronic exposure to opioid receptor antagonists can result in opioid receptor upregulation. The\\u000a phenomenon of antagonist-induced receptor upregulation is not unique to the opioid system but is common to many receptor systems\\u000a including adenergic, cholinergic, serotinergic, and dopaminergic receptors. Chronic administration of naloxone or naltrexone\\u000a reliably produces increases in binding to opioid receptors both in

  15. Evidence against specific binding of salicylic acid to plant catalase.

    PubMed

    Rüffer, M; Steipe, B; Zenk, M H

    1995-12-18

    It was demonstrated that salicylic acid (SA) not only binds to catalase from differentiated higher plants and plant cell suspension cultures but also to those of fungi and animals. SA bound specifically to iron-containing enzymes, such as catalase, aconitase, lipoxidase and peroxidase, while not to iron-free plant enzymes. On the grounds of these experiments, the claim is further challenged that SA is a signalling compound and second messenger in plants that activates plant defense-related genes through elevated H2O2 levels by specifically inhibiting catalase activity. SA may just function as a phytoalexin. PMID:8543045

  16. Catalase Enhances Growth and Biofilm Production of Mycoplasma pneumoniae.

    PubMed

    Simmons, Warren L; Dybvig, Kevin

    2015-08-01

    Mycoplasma pneumoniae causes chronic respiratory disease in humans. Factors thought to be important for colonization include the ability of the mycoplasma to form a biofilm on epithelial surfaces and the production of hydrogen peroxide to damage host tissue. Almost all of the mycoplasmas, including M. pneumoniae, lack superoxide dismutase and catalase and a balance should exist between peroxide production and growth. We show here that the addition of catalase to cultures enhanced the formation of biofilms and altered the structure. The incorporation of catalase in agar increased the number of colony-forming units detected and hence could improve the clinical diagnosis of mycoplasmal diseases. PMID:25894997

  17. Catalases as biocatalysts in technical applications: current state and perspectives.

    PubMed

    Lon?ar, Nikola; Fraaije, Marco W

    2015-04-01

    Catalases represent a class of enzymes which has found its place among industrially relevant biocatalysts due to their exceptional catalytic rate and high stability. Textile bleaching prior to the dyeing process is the main application and has been performed on a large scale for the past few decades. Their limited substrate scope has not prevented the development of various other catalase-based applications. Newly developed approaches continue to exploit their excellent catalytic potential to degrade hydrogen peroxide while (per)oxidase activity of catalases is opening a new range of possibilities as well. This review provides an overview of applications that involve heme-containing catalases that have been demonstrated in recent years. PMID:25761626

  18. HYDROGEN PEROXIDE INDUCED OXIDATION OF PEROXISOMAL MALATE SYNTHASE AND CATALASE.

    E-print Network

    Simha, Rahul

    locations within the proteins' structures. Key words: biotin hydrazide, carbonylation, catalase, hydrogen carbon cycle, which begins in the chloroplast when O2 replaces CO2 in the RuBisCo reaction [5]. In those

  19. Targeting of superoxide dismutase and catalase to vascular endothelium

    Microsoft Academic Search

    Vladimir R Muzykantov

    2001-01-01

    Reactive oxygen species, such as superoxide anion (O2?) and H2O2, cause oxidative stress in endothelial cells, a condition implicated in the pathogenesis of many cardiovascular and pulmonary diseases. Antioxidant enzymes, superoxide dismutases (SOD, converting superoxide anion into H2O2) and catalase (converting H2O2 into water), are candidate drugs for augmentation of antioxidant defenses in endothelium. However, SOD and catalase undergo fast

  20. SOD and catalase inactivation by singlet oxygen and peroxyl radicals

    Microsoft Academic Search

    J. A. Escobar; M. A. Rubio; E. A. Lissi

    1996-01-01

    Both superoxide dismutase and catalase are readily deactivated by singlet oxygen and by the radicals produced in the pyrolysis of 2,2?-azo-bis-(2-amidinpropano) under aerobic conditions. The rate constant for the loss of enzymatic activity induced by singlet oxygen are 3.9 × 107 and 2.5 × 107 M?1 sec?1 for SOD and catalase, respectively. The similarity between these values implies that in

  1. Differential Expression of Catalase Genes in Nicotiana plumbaginifolia (L.)

    Microsoft Academic Search

    Hilde Willekens; Christian Langebartels; Christine Tire; Marc van Montagu; Dirk Inze; Wim van Camp

    1994-01-01

    We have analyzed the expression of three catalase (Cat; EC 1.11.1.6) genes from Nicotiana plumbaginifolia by means of RNA blot and in situ hybridizations. Our data demonstrate that the expression of each catalase is associated with a particular H_2O_2-producing process. Cat1 appears to be specifically involved in the scavenging of photorespiratory H_2O_2 and is under control of a circadian rhythm,

  2. Cytochemical discrimination between catalases and peroxidases using diaminobenzidine

    Microsoft Academic Search

    Frank Roels; Eddie Wisse; Betty Prest; Jannes Meulen

    1975-01-01

    The influence on diaminobenzidine staining of four variables: prefixation in aldehyde, temperature and pH of incubation, and H2O2 concentration, was investigated in catalase-, as well as in peroxydase-containing material. Catalase from five different sources and five types of peroxidase were examine. It is conclude: (a) when cells are incubated without prior fixation, in a DAB medium at room temperature and

  3. Conversion of the synthetic catalase mimic precursor TAA-1 into the active catalase mimic in isolated hepatocytes.

    PubMed

    Rauen, Ursula; Kettler-Thiel, Thorsten; de Groot, Herbert; Korth, Hans-Gert; Sustmann, Reiner

    2009-05-01

    In previous studies we reported on the catalase-like activity and antioxidative properties of a non-heme Fe(III)-tetraaza[14]annulene complex, 5,4-didehydro-5,9,14,18-tetraaza-di(2,2-dimethyl-[5,6]benzo[1,3]dioxolo)[a,h]cyclotetradecene--Fe(III) chloride (TAA-1/Fe). We proposed that intracellular application of the parent, iron-free tetraaza[14]annulene ligand, TAA-1, as precursor would allow antioxidative defense along two lines, i.e. by chelation of potentially toxic cellular iron ions and, subsequently, by catalase-mimic activity. We here set out to establish whether the active catalase mimic is indeed formed intracellularly when cells are loaded with the ligand. When isolated rat hepatocytes were preloaded with TAA-1, they were protected against iron-induced cell injury and oxidative stress elicited by exposure to the membrane-permeable iron complex Fe(III)/8-hydroxyquinoline. After lysis of the cells, followed by ultrafiltration to remove endogenous catalase, the lysate exhibited catalase-like activity, while lysates of control cells not treated with TAA-1 showed no catalase-like activity. By comparison with authentic TAA-1/Fe, an intracellular formation of 2.0 +/- 0.3 microm of the active catalase mimic in native hepatocytes exposed to TAA-1 and of 6.5 +/- 1.0 microm in hepatocytes exposed to both TAA-1 and iron ions was estimated. The intracellular formation of the active catalase mimic thus renders TAA-1 an attractive compound for protection against iron- and/or hydrogen peroxide-dependent cell injuries. PMID:19366358

  4. Purification and biosynthesis of cottonseed (Gossypium hirsutum L.) catalase.

    PubMed Central

    Kunce, C M; Trelease, R N; Turley, R B

    1988-01-01

    As part of our research on peroxisome biogenesis, catalase was purified from cotyledons of dark-grown cotton (Gossypium hirsutum L.) seedlings and monospecific antibodies were raised in rabbits. Purified catalase appeared as three distinct electrophoretic forms in non-denaturing gels and as a single protein band (with a subunit Mr of 57,000) on silver-stained SDS/polyacrylamide gels. Western blots of crude extracts and isolated peroxisomes from cotton revealed one immunoreactive polypeptide with the same Mr (57,000) as the purified enzyme, indicating that catalase did not undergo any detectable change in Mr during purification. Synthesis in vitro, directed by polyadenylated RNA isolated from either maturing seeds or cotyledons of dark-grown cotton seedlings, revealed a predominant immunoreactive translation product with a subunit Mr of 57,000 and an additional minor immunoreactive product with a subunit Mr of 64000. Labelling studies in vivo revealed newly synthesized monomers of both the 64000- and 57,000-Mr proteins present in the cytosol and incorporation of both proteins into the peroxisome without proteolytic processing. Within the peroxisome, the 57,000-Mr catalase was found as an 11S tetramer; whereas the 64,000-Mr protein was found as a relatively long-lived 20S aggregate (native Mr approx. 600,000-800,000). The results strongly indicate that the 64,000-Mr protein (catalase?) is not a precursor to the 57,000-Mr catalase and that cotton catalase is translated on cytosolic ribosomes without a cleavable transit or signal sequence. Images Fig. 1. Fig. 3. Fig. 4. Fig. 5. Fig. 6. Fig. 7. Fig. 8. Fig. 9. Fig. 10. PMID:3134010

  5. Purification and biosynthesis of cottonseed (Gossypium hirsutum L.) catalase.

    PubMed

    Kunce, C M; Trelease, R N; Turley, R B

    1988-04-01

    As part of our research on peroxisome biogenesis, catalase was purified from cotyledons of dark-grown cotton (Gossypium hirsutum L.) seedlings and monospecific antibodies were raised in rabbits. Purified catalase appeared as three distinct electrophoretic forms in non-denaturing gels and as a single protein band (with a subunit Mr of 57,000) on silver-stained SDS/polyacrylamide gels. Western blots of crude extracts and isolated peroxisomes from cotton revealed one immunoreactive polypeptide with the same Mr (57,000) as the purified enzyme, indicating that catalase did not undergo any detectable change in Mr during purification. Synthesis in vitro, directed by polyadenylated RNA isolated from either maturing seeds or cotyledons of dark-grown cotton seedlings, revealed a predominant immunoreactive translation product with a subunit Mr of 57,000 and an additional minor immunoreactive product with a subunit Mr of 64000. Labelling studies in vivo revealed newly synthesized monomers of both the 64000- and 57,000-Mr proteins present in the cytosol and incorporation of both proteins into the peroxisome without proteolytic processing. Within the peroxisome, the 57,000-Mr catalase was found as an 11S tetramer; whereas the 64,000-Mr protein was found as a relatively long-lived 20S aggregate (native Mr approx. 600,000-800,000). The results strongly indicate that the 64,000-Mr protein (catalase?) is not a precursor to the 57,000-Mr catalase and that cotton catalase is translated on cytosolic ribosomes without a cleavable transit or signal sequence. PMID:3134010

  6. Catalase, a novel antigen for Helicobacter pylori vaccination.

    PubMed Central

    Radcliff, F J; Hazell, S L; Kolesnikow, T; Doidge, C; Lee, A

    1997-01-01

    The efficacy of an orogastric vaccine comprised of purified Helicobacter pylori catalase plus the mucosal adjuvant cholera toxin (CT) was examined with both the Helicobacter felis and H. pylori mouse models with BALB/c mice. Native H. pylori catalase (200 microg) plus CT was initially used as a vaccine antigen in the H. felis mouse model and protected 80% (8 of 10) of the challenged animals, while all control animals were infected (20 of 20). In a follow-up experiment, recombinant H. pylori catalase plus CT was used for immunization, and groups of mice were challenged with the Sydney strain of H. pylori. Immunization with recombinant catalase protected a significant proportion (9 of 10) of the mice from H. pylori challenge, indicating that this enzyme should be considered as a candidate for a future vaccine. This study provides the first available data on the efficacy of protective immunization with the new Sydney strain of H. pylori in a mouse model. These data also provide indirect evidence that proteins which are normally intracellular, such as catalase, may be present on the surface of H. pylori and thus may provide targets for immunization. PMID:9353048

  7. Catalase-negative Staphylococcus lugdunensis strain with a novel point mutation in the catalase gene isolated from a patient with chronic suppurative otitis media.

    PubMed

    Lu, Yong; Wang, Yiping; Ling, Buzhi; Ke, Xianfu; Ying, Jianfei; Yu, Yanhong; He, Mingyang; Li, Xiangyang

    2013-04-01

    This report describes the results of the sequence analysis of a methicillin-susceptible strain of catalase-negative Staphylococcus lugdunensis. Molecular characterization of the deduced sequence revealed a novel point mutation in the catalase gene. To our knowledge, this is the first report of a catalase-negative S. lugdunensis strain, although catalase-negative isolates of Staphylococcus aureus and Staphylococcus epidermidis have been previously reported. PMID:23345293

  8. Protandim attenuates intimal hyperplasia in human saphenous veins cultured ex vivo via a catalase-dependent pathway.

    PubMed

    Joddar, Binata; Reen, Rashmeet K; Firstenberg, Michael S; Varadharaj, Saradhadevi; McCord, Joe M; Zweier, Jay L; Gooch, Keith J

    2011-03-15

    Human saphenous veins (HSVs) are widely used for bypass grafts despite their relatively low long-term patency. To evaluate the role of reactive oxygen species (ROS) signaling in intima hyperplasia (IH), an early stage pathology of vein-graft disease, and to explore the potential therapeutic effects of up-regulating endogenous antioxidant enzymes, we studied segments of HSV cultured ex vivo in an established ex vivo model of HSV IH. Results showed that HSV cultured ex vivo exhibit an ~3-fold increase in proliferation and ~3.6-fold increase in intimal area relative to freshly isolated HSV. Treatment of HSV during culture with Protandim, a nutritional supplement known to activate Nrf2 and increase the expression of antioxidant enzymes in several in vitro and in vivo models, blocks IH and reduces cellular proliferation to that of freshly isolated HSV. Protandim treatment increased the activity of SOD, HO-1, and catalase 3-, 7-, and 12-fold, respectively, and decreased the levels of superoxide (O(2)(•-)) and the lipid peroxidation product 4-HNE. Blocking catalase activity by cotreating with 3-amino-1,2,4-triazole abrogated the protective effect of Protandim on IH and proliferation. In conclusion, these results suggest that ROS-sensitive signaling mediates the observed IH in cultured HSV and that up-regulation of endogenous antioxidant enzymes can have a protective effect. PMID:21167278

  9. The peroxisomal catalase gene in the methylotrophic yeast Pichia methanolica.

    PubMed

    Nakagawa, Tomoyuki; Yoshida, Kyoko; Takeuchi, Akihito; Ito, Takashi; Fujimura, Shuki; Matsufuji, Yoshimi; Tomizuka, Noboru; Yurimoto, Hiroya; Sakai, Yasuyoshi; Hayakawa, Takashi

    2010-01-01

    In this paper, we describe the CTA1 gene, which encodes a peroxisomal catalase in the methylotrophic yeast Pichia methanolica. The P. methanolica CTA1 gene (PmCTA1) comprises a 1,530-bp open reading frame corresponding to a protein of 510 amino acid residues, and its deduced amino acid sequence shows high similarity to those of Cta1ps from other methylotrophic yeasts (about 79%). Expression of PmCTA1 in a peroxisomal catalase-depleted (Cbcta1Delta) Candida boidinii strain restored the methylotrophic growth of the host strain, while the expression of PmCTA1-DeltaSRL, which lacks peroxisome targeting signal type 1, did not. In P. methanolica, expression of PmCTA1 was induced when cells were grown on peroxisome-inducing carbon sources, viz., methanol, oleate, and D-alanine. Taken together, these results indicate that PmCTA1 encodes a functional peroxisomal catalase in P. methanolica. PMID:20699560

  10. Improving catalase-based propelled motor endurance by enzyme encapsulation.

    PubMed

    Simmchen, Juliane; Baeza, Alejandro; Ruiz-Molina, Daniel; Vallet-Regí, Maria

    2014-08-01

    Biocatalytic propulsion is expected to play an important role in the future of micromotors as it might drastically increase the number of available fuelling reactions. However, most of the enzyme-propelled micromotors so far reported still rely on the degradation of peroxide by catalase, in spite of being vulnerable to relatively high peroxide concentrations. To overcome this limitation, herein we present a strategy to encapsulate the catalase and to graft the resulting enzyme capsules on motor particles. Significant improvement of the stability in the presence of peroxide and other aggressive agents has been observed. PMID:24964766

  11. Heterogeneity of Catalase in Maturing and Germinated Cotton Seeds 1

    PubMed Central

    Kunce, Christine M.; Trelease, Richard N.

    1986-01-01

    To investigate possible charge and size heterogeneity of catalase (EC 1.11.1.6) in cotton (Gossypium hirsutum L. cv Deltapine 62), extracts of cotyledons from different developmental ages were subjected to nondenaturing polyacrylamide gel electrophoresis and isoelectric focusing. Special precautions (e.g. fresh homogenates, reducing media) were necessary to prevent artefacts due to enzyme modification during extraction and storage. When the gels were stained for enzyme activity, two distinct electrophoretic forms of catalase were resolved in extracts of maturing and mature cotton seeds. In germinated seeds, three additional cathodic forms were detected revealing a total of five electrophoretic variants. In green cotyledons, the two anodic forms characteristic of ungerminated seeds were less active; whereas, the most cathodic form was predominant. All forms of catalase were found in isolated glyoxysomes. Corresponding electrophoretic patterns were found on Western blots probed with anticatalase serum; no immunoreactive, catalytically inactive forms were detected. Western blots of sodium dodecyl sulfate-polyacrylamide gels revealed only one immunoreactive (55 kilodaltons) polypeptide in cotton extracts of all developmental ages. Results from isoelectric focusing and Ferguson plots indicate that the electrophoretic variants of catalase are charge isomers with a molecular weight of approximately 230,000. Images Fig. 1 Fig. 2 Fig. 3 Fig. 6 Fig. 7 PMID:16664956

  12. 21 CFR 184.1034 - Catalase (bovine liver).

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ...CAS Reg. No. 81457-95-6) is an enzyme preparation obtained from extracts of...purified liquid or powder. Its characterizing enzyme activity is catalase (EC 1.11.1...requirements and additional requirements for enzyme preparations in the Food...

  13. 21 CFR 184.1034 - Catalase (bovine liver).

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ...CAS Reg. No. 81457-95-6) is an enzyme preparation obtained from extracts of...purified liquid or powder. Its characterizing enzyme activity is catalase (EC 1.11.1...requirements and additional requirements for enzyme preparations in the Food...

  14. 21 CFR 184.1034 - Catalase (bovine liver).

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ...CAS Reg. No. 81457-95-6) is an enzyme preparation obtained from extracts of...purified liquid or powder. Its characterizing enzyme activity is catalase (EC 1.11.1...requirements and additional requirements for enzyme preparations in the Food...

  15. 21 CFR 184.1034 - Catalase (bovine liver).

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ...CAS Reg. No. 81457-95-6) is an enzyme preparation obtained from extracts of...purified liquid or powder. Its characterizing enzyme activity is catalase (EC 1.11.1...requirements and additional requirements for enzyme preparations in the Food...

  16. Improving catalase-based propelled motor endurance by enzyme encapsulation

    NASA Astrophysics Data System (ADS)

    Simmchen, Juliane; Baeza, Alejandro; Ruiz-Molina, Daniel; Vallet-Regí, Maria

    2014-07-01

    Biocatalytic propulsion is expected to play an important role in the future of micromotors as it might drastically increase the number of available fuelling reactions. However, most of the enzyme-propelled micromotors so far reported still rely on the degradation of peroxide by catalase, in spite of being vulnerable to relatively high peroxide concentrations. To overcome this limitation, herein we present a strategy to encapsulate the catalase and to graft the resulting enzyme capsules on motor particles. Significant improvement of the stability in the presence of peroxide and other aggressive agents has been observed.Biocatalytic propulsion is expected to play an important role in the future of micromotors as it might drastically increase the number of available fuelling reactions. However, most of the enzyme-propelled micromotors so far reported still rely on the degradation of peroxide by catalase, in spite of being vulnerable to relatively high peroxide concentrations. To overcome this limitation, herein we present a strategy to encapsulate the catalase and to graft the resulting enzyme capsules on motor particles. Significant improvement of the stability in the presence of peroxide and other aggressive agents has been observed. Electronic supplementary information (ESI) available. See DOI: 10.1039/c4nr02459a

  17. Altered methanol embryopathies in embryo culture with mutant catalase-deficient mice and transgenic mice expressing human catalase

    SciTech Connect

    Miller, Lutfiya [Department of Pharmacology and Toxicology, University of Toronto, Toronto, ON (Canada); Wells, Peter G., E-mail: pg.wells@utoronto.ca [Faculty of Pharmacy, University of Toronto, Toronto, ON (Canada); Department of Pharmacology and Toxicology, University of Toronto, Toronto, ON (Canada)

    2011-04-01

    The mechanisms underlying the teratogenicity of methanol (MeOH) in rodents, unlike its acute toxicity in humans, are unclear, but may involve reactive oxygen species (ROS). Embryonic catalase, although expressed at about 5% of maternal activity, may protect the embryo by detoxifying ROS. This hypothesis was investigated in whole embryo culture to remove confounding maternal factors, including metabolism of MeOH by maternal catalase. C57BL/6 (C57) mouse embryos expressing human catalase (hCat) or their wild-type (C57 WT) controls, and C3Ga.Cg-Catb/J acatalasemic (aCat) mouse embryos or their wild-type C3HeB/FeJ (C3H WT) controls, were explanted on gestational day (GD) 9 (plug = GD 1), exposed for 24 h to 4 mg/ml MeOH or vehicle, and evaluated for functional and morphological changes. hCat and C57 WT vehicle-exposed embryos developed normally. MeOH was embryopathic in C57 WT embryos, evidenced by decreases in anterior neuropore closure, somites developed and turning, whereas hCat embryos were protected. Vehicle-exposed aCat mouse embryos had lower yolk sac diameters compared to C3H WT controls, suggesting that endogenous ROS are embryopathic. MeOH was more embryopathic in aCat embryos than WT controls, with reduced anterior neuropore closure and head length only in catalase-deficient embryos. These data suggest that ROS may be involved in the embryopathic mechanism of methanol, and that embryonic catalase activity may be a determinant of teratological risk.

  18. Immobilization of catalase by using Zr(IV)-modified collagen fiber as the supporting matrix

    Microsoft Academic Search

    Na Song; Shuang Chen; Xin Huang; Xuepin Liao; Bi Shi

    2011-01-01

    Collagen fiber (CF), an abundant natural material of biopolymer, was used as supporting matrix for immobilization of catalase. CF was firstly reacted with Zr(IV), then the catalase was immobilized on Zr(IV)-modified CF (Zr–CF) by adsorption. The structures and properties of Zr–CF and the Zr–CF immobilized catalase (Zr–CF-catalase) were characterized by means of DSC, SEM, FT-IR, etc. It was found that

  19. Structure of the Heme d of Penicillium vitale and Escherichia coli Catalases*

    E-print Network

    Structure of the Heme d of Penicillium vitale and Escherichia coli Catalases* (Received-hydroxychlorin -spirolactone has been found in the crystal structures of Penicillium vitale catalase and Escherichia coli catalase hydroperoxidase II (HPII). The absolute stereochemistry of the two heme d chiral car- bon atoms

  20. Plant Physiol. (1978) 61, 957-960 Effects of Inhibitors of Catalase on Photosynthesis and on

    E-print Network

    Allen, John F.

    1978-01-01

    Plant Physiol. (1978) 61, 957-960 Effects of Inhibitors of Catalase on Photosynthesis and on Catalase Activity in Unwashed Preparations of Intact Chloroplasts Received for publication October 6, 1977] 3RA, United Kingdom ABSTRACT The catalase activity ofunwashed preparations containing intact spinach

  1. Catalase deciency drastically affects gene expression induced by high light in Arabidopsis thaliana

    E-print Network

    Gent, Universiteit

    Catalase de®ciency drastically affects gene expression induced by high light in Arabidopsis imbalances are managed at the production and scavenging levels. Because catalases are the major H2O2 and photorespiratory H2O2-induced cell death in transgenic catalase-de®cient Arabidopsis thaliana. These plants were

  2. research papers 1972 Murshudov et al. Catalase Acta Cryst. (2002). D58, 19721982

    E-print Network

    2002-01-01

    research papers 1972 Murshudov et al. Catalase Acta Cryst. (2002). D58, 1972±1982 Acta catalase, its ferryl intermediate (compound II) and NADPH complex Garib N. Murshudov,a * Albina I. Grebenko structure of the bacterial catalase from Micro- coccus lysodeikticus has been re®ned using the gene

  3. The grid sectioning technique: a study of catalase platelets.

    PubMed

    Jésior, J C

    1982-01-01

    The grid sectioning technique has been used to obtain the two missing principal axis projections of orthorhombic catalase platelets and to measure directly the unit cell c-value. The negatively stained platelets have a unit cell c-dimension of half that proposed by Unwin (1975) from powder X-ray diffraction. The precision of the grid sectioning technique in positioning sections along a specimen axis shows that the growth fault lines usually observed on negatively stained catalase platelets are rows of missing molecules filled with stain. From these sections conclusions are drawn concerning the action of negative stain on a specimen, the microtomy process, and the specimen/supporting film interaction. Finally the value of microtomy for detailed structural analysis of biological objects is emphasized. PMID:7188250

  4. Structure of catalase determined by MicroED

    PubMed Central

    Nannenga, Brent L; Shi, Dan; Hattne, Johan; Reyes, Francis E; Gonen, Tamir

    2014-01-01

    MicroED is a recently developed method that uses electron diffraction for structure determination from very small three-dimensional crystals of biological material. Previously we used a series of still diffraction patterns to determine the structure of lysozyme at 2.9 Å resolution with MicroED (Shi et al., 2013). Here we present the structure of bovine liver catalase determined from a single crystal at 3.2 Å resolution by MicroED. The data were collected by continuous rotation of the sample under constant exposure and were processed and refined using standard programs for X-ray crystallography. The ability of MicroED to determine the structure of bovine liver catalase, a protein that has long resisted atomic analysis by traditional electron crystallography, demonstrates the potential of this method for structure determination. DOI: http://dx.doi.org/10.7554/eLife.03600.001 PMID:25303172

  5. Two distinct groups of fungal catalase/peroxidases

    PubMed Central

    Zámocký, Marcel; Furtmüller, Paul G.; Obinger, Christian

    2011-01-01

    Catalase/peroxidases (KatGs) are bifunctional haem b-containing (Class I) peroxidases with overwhelming catalase activity and substantial peroxidase activity with various one-electron donors. These unique oxidoreductases evolved in ancestral bacteria revealing a complex gene-duplicated structure. Besides being found in numerous bacteria of all phyla, katG genes were also detected in genomes of lower eukaryotes, most prominently of sac and club fungi. Phylogenetic analysis demonstrates the occurrence of two distinct groups of fungal KatGs that differ in localization, structural and functional properties. Analysis of lateral gene transfer of bacterial katGs into fungal genomes reveals that the most probable progenitor was a katG from a bacteroidetes predecessor. The putative physiological role(s) of both fungal KatG groups is discussed with respect to known structure–function relationships in bacterial KatGs and is related with the acquisition of (phyto)pathogenicity in fungi. PMID:19614592

  6. Genes Important for Catalase Activity in Enterococcus faecalis

    Microsoft Academic Search

    Michael Baureder; Lars Hederstedt

    2012-01-01

    Little in general is known about how heme proteins are assembled from their constituents in cells. The Gram-positive bacterium Enterococcus faecalis cannot synthesize heme and does not depend on it for growth. However, when supplied with heme in the growth medium the cells can synthesize two heme proteins; catalase (KatA) and cytochrome bd (CydAB). To identify novel factors important for

  7. Tritium effect in peroxidation of ehtanol by liver catalase.

    PubMed Central

    Damgaard, S E

    1977-01-01

    1. Simultaneous determination of the rate of appearance of 3H in water from [(1R)-1-3H1] ethanol and the rate of acetaldehyde formation in the presence of rat or ox liver catalase under conditions of steady-state generation of H2O2 allowed calculation of the 3H isotope effect. The mean value of 2.52 obtained for rat liver catalase at 37 degrees C and pH 6.3-7.7 was independent of both ethanol concentration and the rate of H2O2 generation over a wide range. At 25 degrees C a slightly lower mean value of 2.40 was obtained with the ox liver catalase. 2. Neither the product, acetaldehyde, nor 4-methylpyrazole influenced the two rates measured in the assay. 3. Relating the value obtained for the 3H isotope effect to a known value for the 2H isotope effect strongly supports the view that both values are close to the true isotope effect with the respective substituted compounds on the rate constant in the catalytic step involving scission of the C-H bond. 4. The constancy of the isotope effect under various conditions makes it possible to use it for interpretations in vivo. 5. It was established that beta-D-galactose dehydrogenase exhibits B-specificity towards the nicotinamide ring in NAD. PMID:22327

  8. PIKfyve upregulates CFTR activity.

    PubMed

    Gehring, Eva-Maria; Lam, Rebecca S; Siraskar, Gulab; Koutsouki, Evgenia; Seebohm, Guiscard; Ureche, Oana N; Ureche, Liviu; Baltaev, Ravshan; Tavare, Jeremy M; Lang, Florian

    2009-12-18

    The cystic fibrosis transmembrane conductance regulator (CFTR) is a cAMP-activated Cl(-) channel critically important in Cl(-) secreting epithelia. Mutations in the CFTR gene, such as (DeltaF508)CFTR leads to cystic fibrosis, a severe disease with defective Cl(-) secretion. CFTR is stimulated by the serum and glucocorticoid-inducible kinase SGK1. The SGK1 dependent regulation of several carriers and channels involves the phosphatidylinositol-3-phosphate-5-kinase PIKfyve, which similarly mediates the regulation of glucose carriers by PKB/Akt. The present study was thus performed to elucidate whether PKB/Akt and PIKfyve are regulators of CFTR. To this end CFTR or (DeltaF508)CFTR were expressed in Xenopus oocytes alone or together with PKB, PIKfyve or the SGK1/PKB resistant mutant (S318A)PIKfyve, and the current generated by cAMP upregulation with 10muM forskolin+1mM IBMX determined utilizing dual electrode voltage clamp. As a result, forskolin/IBMX treatment triggered a current (I(cAMP)) in CFTR-expressing Xenopus oocytes, but not in oocytes expressing (DeltaF508)CFTR. Coexpression of PKB/Akt and PIKfyve, but not of (S318A)PIKfyve, stimulated I(cAMP) in CFTR-expressing ( approximately 2- to 3-fold) but not in (DeltaF508)CFTR-expressing or water injected Xenopus oocytes. Immunohistochemistry revealed that the coexpression of PIKfyve, but not of (S318A)PIKfyve, enhanced the CFTR protein abundance but not the (DeltaF508)CFTR protein abundance in CFTR or (DeltaF508)CFTR-expressing oocytes. The present observations reveal a novel powerful regulator of intact but not of defective CFTR. PMID:19852935

  9. Plating isolation of various catalase-negative microorganisms from soil

    NASA Technical Reports Server (NTRS)

    Labeda, D. P.; Hunt, C. M.; Casida, L. E., Jr.

    1974-01-01

    A unique plating procedure was developed that allows isolation, but not enumeration, of representatives of the catalase-negative soil microflora. The numbers recovered, however, are low as compared to the numbers recovered when the modified dilution-to-extinction isolation procedure is used. The latter procedure provides prolonged inoculation in sealed tubes containing a nutritionally rich broth medium over small submerged agar slants. In contrast, the plating procedure utilizes nutritionally minimal media and the shorter incubations mandated by the inherent problems associated with plating.

  10. Purification and characterization of catalase from marine bacterium Acinetobacter sp. YS0810.

    PubMed

    Fu, Xinhua; Wang, Wei; Hao, Jianhua; Zhu, Xianglin; Sun, Mi

    2014-01-01

    The catalase from marine bacterium Acinetobacter sp. YS0810 (YS0810CAT) was purified and characterized. Consecutive steps were used to achieve the purified enzyme as follows: ethanol precipitation, DEAE Sepharose ion exchange, Superdex 200 gel filtration, and Resource Q ion exchange. The active enzyme consisted of four identical subunits of 57.256 kDa. It showed a Soret peak at 405 nm, indicating the presence of iron protoporphyrin IX. The catalase was not apparently reduced by sodium dithionite but was inhibited by 3-amino-1,2,4-triazole, hydroxylamine hydrochloride, and sodium azide. Peroxidase-like activity was not found with the substrate o-phenylenediamine. So the catalase was determined to be a monofunctional catalase. N-terminal amino acid of the catalase analysis gave the sequence SQDPKKCPVTHLTTE, which showed high degree of homology with those of known catalases from bacteria. The analysis of amino acid sequence of the purified catalase by matrix-assisted laser desorption ionization time-of-flight mass spectrometry showed that it was a new catalase, in spite of its high homology with those of known catalases from other bacteria. The catalase showed high alkali stability and thermostability. PMID:25045672

  11. Purification and Characterization of Catalase from Marine Bacterium Acinetobacter sp. YS0810

    PubMed Central

    Fu, Xinhua; Wang, Wei; Hao, Jianhua; Zhu, Xianglin; Sun, Mi

    2014-01-01

    The catalase from marine bacterium Acinetobacter sp. YS0810 (YS0810CAT) was purified and characterized. Consecutive steps were used to achieve the purified enzyme as follows: ethanol precipitation, DEAE Sepharose ion exchange, Superdex 200 gel filtration, and Resource Q ion exchange. The active enzyme consisted of four identical subunits of 57.256?kDa. It showed a Soret peak at 405?nm, indicating the presence of iron protoporphyrin IX. The catalase was not apparently reduced by sodium dithionite but was inhibited by 3-amino-1,2,4-triazole, hydroxylamine hydrochloride, and sodium azide. Peroxidase-like activity was not found with the substrate o-phenylenediamine. So the catalase was determined to be a monofunctional catalase. N-terminal amino acid of the catalase analysis gave the sequence SQDPKKCPVTHLTTE, which showed high degree of homology with those of known catalases from bacteria. The analysis of amino acid sequence of the purified catalase by matrix-assisted laser desorption ionization time-of-flight mass spectrometry showed that it was a new catalase, in spite of its high homology with those of known catalases from other bacteria. The catalase showed high alkali stability and thermostability. PMID:25045672

  12. Catalase degradation in sunflower cotyledons during peroxisome transition from glyoxysomal to leaf peroxisomal function. [Helianthus annuus

    SciTech Connect

    Eising, R.; Gerhardt, B.

    1987-06-01

    First order rate constant for the degradation (degradation constants) of catalase in the cotyledons of sunflower (Helianthus annuus L.) were determined by measuring the loss of catalase containing /sup 14/C-labeled heme. During greening of the cotyledons, a period when peroxisomes change from glyoxysomal to leaf peroxisomal function, the degradation of glyoxysomal catalase is significantly slower than during all other stages of cotyledon development in light or darkness. The degradation constant during the transition stage of peroxisome function amounts to 0.205 day/sup -1/ in contrast to the constants ranging from 0.304 day/sup -1/ to 0.515 day/sup -1/ during the other developmental stages. Density labeling experiments comprising labeling of catalase with /sup 2/H/sub 2/O and its isopycnic centrifugation on CsCl gradients demonstrated that the determinations of the degradation constants were not substantially affected by reutilization of /sup 14/C-labeled compounds for catalase synthesis. The degradation constants for both glyoxysomal catalase and catalase synthesized during the transition of peroxisome function do not differ. This was shown by labeling the catalases with different isotopes and measuring the isotope ratio during the development of the cotyledons. The results are inconsistent with the concept that an accelerated and selective degradation of glyoxysomes underlies the change in peroxisome function. The data suggest that catalase degradation is at least partially due to an individual turnover of catalase and does not only result from a turnover of the whole peroxisomes.

  13. Endothelin-1 stimulates catalase activity through the PKC? mediated phosphorylation of Serine 167

    PubMed Central

    Rafikov, Ruslan; Kumar, Sanjiv; Aggarwal, Saurabh; Hou, Yali; Kangath, Archana; Pardo, Daniel; Fineman, Jeffrey R.; Black, Stephen M.

    2013-01-01

    Our previous studies have shown that endothelin-1 (ET-1) stimulates catalase activity in endothelial cells and lambs with acute increases in pulmonary blood flow (PBF), without altering gene expression. The purpose of this study was to investigate the molecular mechanism by which this occurs. Exposing pulmonary arterial endothelial cells (PAEC) to ET-1 increased catalase activity and decreased cellular hydrogen peroxide (H2O2) levels. These changes correlated with an increase in serine phosphorylated catalase. Using the inhibitory peptide ?V1.1, this phosphorylation was shown to be PKC? dependent. Mass spectrometry identified serine167 as the phosphorylation site. Site-directed mutagenesis was used to generate a phospho-mimic (S167D) catalase. Activity assays using recombinant protein purified from E.coli or transiently transfected COS-7 cells, demonstrated that S167D-catalase had an increased ability to degrade H2O2 compared to the wildtype enzyme. Using a phospho-specific antibody, we were able to verify that pS167 catalase levels are modulated in lambs with acute increases in PBF in the presence and absence of the ET receptor antagonist, tezosentan. S167 is being located on the dimeric interface suggesting it could be involved in regulating the formation of catalase tetramers. To evaluate this possibility we utilized analytical gel-filtration to examine the multimeric structure of recombinant wildtype- and S167D-catalase. We found that recombinant wildtype catalase was present as a mixture of monomers and dimers while S167D catalase was primarily tetrameric. Further, the incubation of wildtype catalase with PKC? was sufficient to convert wildtype catalase into a tetrameric structure. In conclusion, this is the first report indicating that the phosphorylation of catalase regulates its multimeric structure and activity. PMID:24211614

  14. Dierential developmental expression and cell type specicity of Dictyostelium catalases and their response to oxidative stress and

    E-print Network

    Devreotes, Peter

    Di¡erential developmental expression and cell type speci¢city of Dictyostelium catalases the Dictyostelium catalase and Cu/Zn superoxide dismutase antioxidant enzymes. We show that there are two catalase oxidative damage. We found that exposure to H2O2 does not result in the induction of the catalase

  15. Cytochemical localization of catalase in leaf microbodies (peroxisomes).

    PubMed

    Frederick, S E; Newcomb, E H

    1969-11-01

    Segments of mature tobacco leaves were fixed in glutaraldehyde, incubated in medium containing 3,3'-diaminobenzidine (DAB) and hydrogen peroxide, and postfixed in osmium tetroxide. Electron microscopic observation of treated tissues revealed pronounced deposition of a highly electron-opaque material in microbodies but not in other organelles. The coarsely granular reaction product is presumably osmium black formed by reaction of oxidized DAB with osmium tetroxide. Reaction of the microbodies with DAB was completely inhibited by 0.02 M 3-amino-1,2,4-triazole and was considerably reduced by 0.01 M potassium cyanide. These results, when considered in light of recent biochemical studies, strongly suggest that catalase is responsible for the reaction. Sharp localization of this enzyme in microbodies establishes that they are identical to the catalase-rich "peroxisomes" recently isolated from leaf cell homogenates. A browning reaction that occurred in leaves during the incubation step was inhibited by cyanide but not by aminotriazole and therefore could not have been caused by the same enzyme. This reaction and a slight deposition of dense material within primary and secondary walls are ascribed to oxidation of DAB by soluble and wall-localized peroxidases. PMID:4981071

  16. A method for molecular analysis of catalase gene diversity in seawater.

    PubMed

    Wang, Wei; Ji, Xiaofeng; Yuan, Cui; Dai, Fangqun; Zhu, Jiancheng; Sun, Mi

    2013-12-01

    Catalase plays an important role in the metabolism of marine bacteria and has potential impact on the marine environment. Four PCR primers were designed to amplify the catalase gene fragments in marine bacteria by applying metagenomic DNA from Yellow Sea surface water as the template. Of the four reproducible target PCR products, the longest one with 900 bp were chosen for catalase gene library construction by the T-vector and the white Escherichia coli colonies in the library was screened through restriction-digesting the reamplified insert fragments by the selected restriction endonuclease MboI, and then the bands of the resulting products were displayed in the agarose gel by electrophoresis. The unique restriction fragment length polymorphism (RFLP) pattern was selected and the corresponding catalase gene fragments were sequenced, which verified that every unique RFLP pattern represented one type of catalase. This PCR-RFLP method above was established to investigate the bacterial catalase diversity in seawater. PMID:24426153

  17. Fluorescence Spectrometry of the Interaction of Multi-Walled Carbon Nanotubes with Catalase

    NASA Astrophysics Data System (ADS)

    Fan, Y.; Li, Y.; Cai, H.; Li, J.; Miao, J.; Fu, D.; Yang, Q.

    2014-11-01

    The interaction of multi-walled carbon nanotubes (MWCNTs) with catalase is investigated using fluorescence and circular dichroism spectroscopic techniques. The results of the fluorescence experiments suggest that MWCNTs quench the intrinsic fluorescence of catalase via a static quenching mechanism. The circular dichroism spectral results reveal the unfolding of catalase with a significant decrease in the ?-helix content in the presence of MWCNTs, which indicates that the conformation of catalase is changed in the binding process, thereby remarkably decreasing its activity. The binding constants and the number of binding sites of the MWCNT to the catalase are calculated at different temperatures. The thermodynamic parameters, such as the changes in free energy (?G), enthalpy (?H), and entropy (?S), are calculated using thermodynamic equations. The fact that all negative values of ?G, ?H, and ?S are obtained suggests that the interaction of the MWCNTs with catalase is spontaneous, and that hydrogen bonding and van der Waals interactions play an important role in the binding process.

  18. Stability of catalase and its role in lipid oxidation in beef muscle 

    E-print Network

    Pradhan, Abhijeet Amar

    1997-01-01

    H and additives on linoleate oxidation catalyzed by metrnyoglobin (MetMb), Fe2+-EDTA (1:1) chelate and raw beef homogenates, and concluded that the catalytic activity of raw beef homogenates was due to both heme iron and nonherne iron. On the other hand... Part I Part II Chemical analyses TBARS assay Peroxide value Catalase activity Statistical analysis RESULTS AND DISCUSSION Stabililty of catalase Catalase and lipid oxidation potential CONCLUSIONS REFERENCES VITA Page . . . Vt . . V11...

  19. A bioinspired polymer-bound Mn-porphyrin as an artificial active center of catalase.

    PubMed

    Kubota, Riku; Asayama, Shoichiro; Kawakami, Hiroyoshi

    2014-12-28

    The complex comprising a cationic Mn-porphyrin and carboxymethyl poly(1-vinylimidazole) (CM-PVIm) was prepared as an artificial active center of catalase. Interestingly, the catalase activity of the complex depends on the chain length of the polymer and the chemical structure of Mn-porphyrin. This study is one step forward in the development of a new class of water-soluble catalase mimics. PMID:25380330

  20. Bacterial Catalase in the Microsporidian Nosema locustae: Implications for Microsporidian Metabolism and Genome Evolution

    PubMed Central

    Fast, Naomi M.; Law, Joyce S.; Williams, Bryony A. P.; Keeling, Patrick J.

    2003-01-01

    Microsporidia constitute a group of extremely specialized intracellular parasites that infect virtually all animals. They are highly derived, reduced fungi that lack several features typical of other eukaryotes, including canonical mitochondria, flagella, and peroxisomes. Consistent with the absence of peroxisomes in microsporidia, the recently completed genome of the microsporidian Encephalitozoon cuniculi lacks a gene for catalase, the major enzymatic marker for the organelle. We show, however, that the genome of the microsporidian Nosema locustae, in contrast to that of E. cuniculi, encodes a group II large-subunit catalase. Surprisingly, phylogenetic analyses indicate that the N. locustae catalase is not specifically related to fungal homologs, as one would expect, but is instead closely related to proteobacterial sequences. This finding indicates that the N. locustae catalase is derived by lateral gene transfer from a bacterium. The catalase gene is adjacent to a large region of the genome that appears to be far less compact than is typical of microsporidian genomes, a characteristic which may make this region more amenable to the insertion of foreign genes. The N. locustae catalase gene is expressed in spores, and the protein is detectable by Western blotting. This type of catalase is a particularly robust enzyme that has been shown to function in dormant cells, indicating that the N. locustae catalase may play some functional role in the spore. There is no evidence that the N. locustae catalase functions in a cryptic peroxisome. PMID:14555490

  1. Layer-by-layer self-assembly immobilization of catalases on wool fabrics.

    PubMed

    Liu, J; Wang, Q; Fan, X R; Sun, X J; Huang, P H

    2013-04-01

    A new immobilization strategy of catalases on natural fibers was reported in this paper. Catalase (CAT) from Bacillus subtilis was assembled into multiple layers together with poly(diallyldimethylammonium chloride) (PDDA) on wool fabrics via layer-by-layer (LBL) electrostatic self-assembly deposition. The mechanism and structural evaluation of LBL electrostatic self-assembly were studied in terms of scanning electron microscopy (SEM), surface zeta potential, and apparent color depth (K/S). The SEM pictures showed obvious deposits absorbed on the wool surfaces after LBL self-assembly. The surface zeta potential and dyeing depth of CAT/PDDA-assembled wool fabrics presented a regular layer-by-layer alternating trend along with the change of deposited materials, revealing the multilayer structure of the wool fiber immobilized catalases. The V(max) values were found to be 2,500±238 U/mg protein for the free catalase and 1,000±102 U/mg protein for the immobilized catalase. The K(m) value of free catalase (11.25±2.3 mM) was found to be lower than that of the immobilized catalase (222.2±36.5 mM). The immobilized catalase remained high enzymatic activity and showed a measureable amount of reusability, which proved that LBL electrostatic self-assembly deposition is a promising approach to immobilize catalases. PMID:23420488

  2. Isolation and characterization of catalase from Penicillium chrysogenum.

    PubMed

    Chaga, G S; Medin, A S; Chaga, S G; Porath, J O

    1992-06-26

    Catalase from a crude preparation of Penicillium chrysogenum was isolated in a single chromatographic step by immobilized metal ion affinity chromatography (IMAC) on Cu(II)-Chelating Sepharose Fast Flow. A chromatographically and electrophoretically homogeneous enzyme was obtained in 89% yield. IMAC was found to be superior to ion-exchange, hydrophobic interaction, size-exclusion and concanavalin A affinity chromatography. Analytical and preparative chromatography gave essentially the same chromatograms. Isoelectric point, molecular weight (by ultracentrifugation), amino acid composition, carbohydrate content and subunit organization were determined. The apparent Michaelis-Menten constant, KM, and the azide competitor constant, Ki, were calculated and found to be 59 microM and 6.1 microM, respectively. PMID:1639925

  3. Compounds I of Catalase and Horse Radish Peroxidase: ?-Cation Radicals

    PubMed Central

    Dolphin, D.; Forman, A.; Borg, D. C.; Fajer, J.; Felton, R. H.

    1971-01-01

    Two-electron oxidation of cobaltous octaethylporphyrin [Co(II)(Et)8P] yields a stable ?-cation radical [Co(III)(Et)8P]2+., the optical spectrum of which exhibits spectral changes dependent upon the nature of the counterion. Comparison of these spectra with those of Compounds I of horseradish peroxidase and catalase leads us to propose that these Compounds I contain a ?-cation radical of the heme prosthetic group. This proposal explains the oxidation level, optical spectra, and stability of the primary compounds without recourse to properties such as stoichiometric mixtures of special porphyrins, stable Fe(V) porphyrins, or unique conformers of heme porphyrins. Explanations are advanced to account for the missing electron spin resonance signal of Compound I of horseradish peroxidase. PMID:5276770

  4. The molecular characterization of a catalase from Chinese mitten crab Eriocheir sinensis.

    PubMed

    Wang, M; Wang, L; Zhou, Z; Gao, Y; Wang, L; Shi, X; Gai, Y; Mu, C; Song, L

    2013-06-01

    Catalase (CAT) is an antioxidant enzyme and plays a significant role in the protection against oxidative stress by reducing hydrogen peroxide. The CAT cDNA of Eriocheir sinensis (EsCAT) was cloned via RACE technique. The complete sequence of EsCAT cDNA consisted of a 5' untranslated regions (UTR) of 224 bp, a 3' UTR of 1287 bp with a poly (A) tail and an open reading frame (ORF) of 1542 bp, which encoded a polypeptide of 513 amino acid residues with a calculated molecular mass of approximately 58.86 kDa and a theoretical isoelectric point of 6.880. The deduced amino acid sequence of EsCAT contained a highly conserved proximal active-site signature motif ((60)FDRERIPERVVHAKGAL(76)) and a proximal heme-ligand signature motif ((350)RLFSYNDTH(358)) and exhibited high similarity with other reported CATs. In the phylogenetic tree, EsCAT was clustered with the CATs from Scylla serrata and Portunus trituberculatus. The EsCAT transcripts were constitutively expressed in haepatopancreas, haemocytes, gill, gonad, muscle and heart, with highest expression level in haepatopancreas. The relative expression level of EsCAT mRNA in haemocytes was continuously up-regulated and reached the peak level at 48 h post-Vibrio anguillarum challenge. The purified recombinant EsCAT protein displayed antioxidant activity against hydrogen peroxide with high thermal stability and broad spectrum of pH values. All these results demonstrated that EsCAT was an efficient antioxidant enzyme and potentially involved in the regulation of redox and innate immune response of crabs. PMID:23171400

  5. Biochemical and genetic analyses of a catalase from the anaerobic bacterium Bacteroides fragilis.

    PubMed Central

    Rocha, E R; Smith, C J

    1995-01-01

    A single catalase enzyme was produced by the anaerobic bacterium Bacteroides fragilis when cultures at late log phase were shifted to aerobic conditions. In anaerobic conditions, catalase activity was detected in stationary-phase cultures, indicating that not only oxygen exposure but also starvation may affect the production of this antioxidant enzyme. The purified enzyme showed a peroxidatic activity when pyrogallol was used as an electron donor. It is a hemoprotein containing one heme molecule per holomer and has an estimated molecular weight of 124,000 to 130,000. The catalase gene was cloned by screening a B. fragilis library for complementation of catalase activity in an Escherichia coli catalase mutant (katE katG) strain. The cloned gene, designated katB, encoded a catalase enzyme with electrophoretic mobility identical to that of the purified protein from the B. fragilis parental strain. The nucleotide sequence of katB revealed a 1,461-bp open reading frame for a protein with 486 amino acids and a predicted molecular weight of 55,905. This result was very close to the 60,000 Da determined by denaturing sodium dodecyl sulfate-polyacrylamide gel electrophoresis of the purified catalase and indicates that the native enzyme is composed of two identical subunits. The N-terminal amino acid sequence of the purified catalase obtained by Edman degradation confirmed that it is a product of katB. The amino acid sequence of KatB showed high similarity to Haemophilus influenzae HktE (71.6% identity, 66% nucleotide identity), as well as to gram-positive bacterial and mammalian catalases. No similarities to bacterial catalase-peroxidase-type enzymes were found. The active-site residues, proximal and distal hemebinding ligands, and NADPH-binding residues of the bovine liver catalase-type enzyme were highly conserved in B. fragilis KatB. PMID:7768808

  6. Regulation of catalase activity in leaves of Nicotiana sylvestris by high CO sub 2

    SciTech Connect

    Havir, E.A.; McHale, N.A. (Connecticut Agricultural Experiment Station, New Haven (USA))

    1989-03-01

    The effect of high CO{sub 2} (1% CO{sub 2}/21% O{sub 2}) on the activity of specific forms of catalase (CAT-1, -2, and -3) in seedling leaves of tobacco (Nicotiana sylvestris, Nicotiana tabacum) was examined. In high CO{sub 2} total catalase activity decreased by 50% in the first 2 days, followed by a more gradual decline in the next 4 days. The loss of total activity resulted primarily from a decrease in CAT-1 catalase. In contrast, the activity of CAT-3 catalase, a form with enhanced peroxidatic activity, increased 3-fold in high CO{sub 2} relative to air controls after 4 days. Short-term exposure to high CO{sub 2} indicated that the 50% loss of total activity occurs in the firs 12 hours. Catalase levels increased to normal within 12 hours after seedlings were returned to air. When seedlings were transferred to air after prolonged exposure to high CO{sub 2} (13 days), the levels of CAT-1 catalase were partially restored while CAT-3 remained at its elevated level. Levels of superoxide dismutase activity and those of several peroxisomal enzymes were not affected by high CO{sub 2}. Total catalase levels did not decline when seedlings were exposed to atmospheres of 0.04% CO{sub 2}/5% O{sub 2} or 0.04% CO{sub 2}/1% O{sub 2}, indicating that regulation of catalase in high CO{sub 2} is not related directly to suppression of photorespiration. Antibodies prepared against CAT-1 catalase from N. tabacum reacted strongly against CAT-1 catalase from both N. sylvestris and N. tabacum but not against CAT-3 catalase from either species.

  7. Brain Levels of Catalase Remain Constant through Strain, Developmental, and Chronic Alcohol Challenges

    PubMed Central

    Rhoads, Dennis E.; Contreras, Cherly; Fathalla, Salma

    2012-01-01

    Catalase (EC 1.11.1.6) oxidizes ethanol to acetaldehyde within the brain and variations in catalase activity may underlie some consequences of ethanol consumption. The goals of this study were to measure catalase activity in subcellular fractions from rat brain and to compare the levels of this enzyme in several important settings. In the first series of studies, levels of catalase were compared between juvenile and adult rats and between the Long-Evans (LE) and Sprague-Dawley (SD) strains. Levels of catalase appear to have achieved the adult level by the preadolescent period defined by postnatal age (P, days) P25–P28, and there were no differences between strains at the developmental stages tested. Thus, variation in catalase activity is unlikely to be responsible for differences in how adolescent and adult rats respond to ethanol. In the second series of studies, periadolescent and adult rats were administered ethanol chronically through an ethanol-containing liquid diet. Diet consumption and blood ethanol concentrations were significantly higher for periadolescent rats. Catalase activities remained unchanged following ethanol consumption, with no significant differences within or between strains. Thus, the brain showed no apparent adaptive changes in levels of catalase, even when faced with the high levels of ethanol consumption characteristic of periadolescent rats. PMID:22919469

  8. Catalase addition to vitrification solutions maintains goat ovarian preantral follicles stability.

    PubMed

    Carvalho, A A; Faustino, L R; Silva, C M G; Castro, S V; Lobo, C H; Santos, F W; Santos, R R; Campello, C C; Bordignon, V; Figueiredo, J R; Rodrigues, A P R

    2014-08-01

    The aim of this study was to verify whether the addition of catalase (20?IU/mL) at different steps of goat ovarian tissue vitrification affects ROS levels, follicular morphology and viability, stromal cell density, apoptosis and the expression of proteins related to DNA-damage signaling (?H2AX) and repair (53BP1). Goat ovarian tissues were analyzed fresh (control) or after vitrification: without catalase (VS-/WS-), with catalase in vitrification solutions (VS+/WS-), with catalase in washing solutions (VS-/WS+) or with catalase in both solutions (VS+/WS+). The vitrification without catalase had higher ROS levels than the control. The catalase, regardless the step of addition, maintained ROS levels similar to the control. There were no difference between treatments regarding follicular viability, stromal cell density and detection of ?H2AX and 53BP1. There was no difference in follicular morphology and DNA fragmentation between groups vitrified. In conclusion, catalase addition to vitrification solutions prevents ROS formation in cryopreserved goat ovarian tissues. PMID:24972862

  9. THE USE OF BEEF LIVER CATALASE AS A PROTEIN TRACER FOR ELECTRON MICROSCOPY

    Microsoft Academic Search

    M. A. VENKATACHALAM; H. DARIUSH FAHIMI

    2009-01-01

    Beef liver catalase was injected intravenously into mice, and its distribution in the kidney, myocardium, and liver was studied with the electron microscope .A specific and relatively sensitive method was developed for its ultrastructural localization, based on the peroxidatic activity of catalase and employing a modified Graham and Karnovsky incubation medium. The main features of the medium were a higher

  10. Inhibition of catalase activity by oxidative stress and its relationship to salicylic acid accumulation in plants

    Microsoft Academic Search

    Ie-Sung Shim; Yukie Momose; Akihiro Yamamoto; Dea-Wook Kim; Kenji Usui

    2003-01-01

    The decrease in catalase activity and its relationship to change in salicylic acid content were investigated in rice, wheat, and cucumber seedlings exposed to oxidative stresses. A decrease in chlorophyll fluorescence (?F\\/Fm'), measured as an indicator of the oxidative stress, and a drop in catalase activity were observed following treatment with NaCl in all plant seedlings tested . Furthermore, such

  11. CHARACTERIZATION OF CATALASE ACTIVITIES IN A ROOT-CLEANING ISOLATE OF PSEUDOMONAS PUTIDA

    EPA Science Inventory

    Psuedomonas putida, a saprophytic root-colonizing bacterium, produces multiple forms of catalase Catalase A which increases in specific activity during growth phase and after treatment with H2O2, is located in the and is inhibited by 3-amino-1,2-4-triazole, EDTA, and cyanide, but...

  12. Determination of calcium in milk and water samples by using catalase enzyme electrode

    Microsoft Academic Search

    Erol Akyilmaz; Ozge Kozgus

    2009-01-01

    A biosensor based on catalase enzyme was developed for the investigation of the effect of calcium ions on the activity of the enzyme. Calcium plays an activator role for the catalase enzyme that catalyses the degradation of hydrogen peroxide to O2 and H2O. Determination method of the effect of calcium ion on the activity of the enzyme was based on

  13. Interaction and complex formation between catalase and cationic polyelectrolytes: Chitosan and Eudragit E100

    Microsoft Academic Search

    Valeria Boeris; Diana Romanini; Beatriz Farruggia; Guillemo Picó

    2009-01-01

    Interactions between catalase and the cationic polyelectrolytes: chitosan and Eudragit E100 have been investigated owing to their scientific and technological importance. These interactions have been characterized by turbidimetry, circular dichroism and fluorescence spectroscopy. It was found that the catalase conformation does not change significantly during the chain entanglements between the protein and the polyelectrolytes. The effects of pH, ionic strength

  14. Cloning and sequencing of a Candida albicans catalase gene and effects of disruption of this gene.

    PubMed

    Wysong, D R; Christin, L; Sugar, A M; Robbins, P W; Diamond, R D

    1998-05-01

    Catalase plays a key role as an antioxidant, protecting aerobic organisms from the toxic effects of hydrogen peroxide, and in some cases has been postulated to be a virulence factor. To help elucidate the function of catalase in Candida albicans, a single C. albicans-derived catalase gene, designated CAT1, was isolated and cloned. Degenerate PCR primers based on highly conserved areas of other fungal catalase genes were used to amplify a 411-bp product from genomic DNA of C. albicans ATCC 10261. By using this product as a probe, catalase clones were isolated from genomic libraries of C. albicans. Nucleotide sequence analysis revealed an open reading frame encoding a protein of 487 amino acid residues. Construction of a CAT1-deficient mutant was achieved by using the Ura-blaster technique for sequential disruption of multiple alleles by integrative transformation using URA3 as a selectable marker. Resulting mutants exhibited normal morphology and comparable growth rates of both yeast and mycelial forms. Enzymatic analysis revealed an abundance of catalase in the wild-type strain but decreasing catalase activity in heterozygous mutants and no detectable catalase in a homozygous null mutant. In vitro assays showed the mutant strains to be more sensitive to damage by both neutrophils and concentrations of exogenous peroxide that were sublethal for the parental strain. Compared to the parental strain, the homozygous null mutant strain was far less virulent for mice in an intravenous infection model of disseminated candidiasis. Definitive linkage of CAT1 with virulence would require restoration of activity by reintroduction of the gene into mutants. However, initial results in mice, taken together with the enhanced susceptibility of catalase-deficient hyphae to damage by human neutrophils, suggest that catalase may enhance the pathogenicity of C. albicans. PMID:9573075

  15. Catalase inhibits ionizing radiation-induced apoptosis in hematopoietic stem and progenitor cells.

    PubMed

    Xiao, Xia; Luo, Hongmei; Vanek, Kenneth N; LaRue, Amanda C; Schulte, Bradley A; Wang, Gavin Y

    2015-06-01

    Hematologic toxicity is a major cause of mortality in radiation emergency scenarios and a primary side effect concern in patients undergoing chemo-radiotherapy. Therefore, there is a critical need for the development of novel and more effective approaches to manage this side effect. Catalase is a potent antioxidant enzyme that coverts hydrogen peroxide into hydrogen and water. In this study, we evaluated the efficacy of catalase as a protectant against ionizing radiation (IR)-induced toxicity in hematopoietic stem and progenitor cells (HSPCs). The results revealed that catalase treatment markedly inhibits IR-induced apoptosis in murine hematopoietic stem cells and hematopoietic progenitor cells. Subsequent colony-forming cell and cobble-stone area-forming cell assays showed that catalase-treated HSPCs can not only survive irradiation-induced apoptosis but also have higher clonogenic capacity, compared with vehicle-treated cells. Moreover, transplantation of catalase-treated irradiated HSPCs results in high levels of multi-lineage and long-term engraftments, whereas vehicle-treated irradiated HSPCs exhibit very limited hematopoiesis reconstituting capacity. Mechanistically, catalase treatment attenuates IR-induced DNA double-strand breaks and inhibits reactive oxygen species. Unexpectedly, we found that the radioprotective effect of catalase is associated with activation of the signal transducer and activator of transcription 3 (STAT3) signaling pathway and pharmacological inhibition of STAT3 abolishes the protective activity of catalase, suggesting that catalase may protect HSPCs against IR-induced toxicity via promoting STAT3 activation. Collectively, these results demonstrate a previously unrecognized mechanism by which catalase inhibits IR-induced DNA damage and apoptosis in HSPCs. PMID:25603016

  16. Mitochondrial targeted catalase suppresses invasive breast cancer in mice

    PubMed Central

    2011-01-01

    Background Treatment of invasive breast cancer has an alarmingly high rate of failure because effective targets have not been identified. One potential target is mitochondrial generated reactive oxygen species (ROS) because ROS production has been associated with changes in substrate metabolism and lower concentration of anti-oxidant enzymes in tumor and stromal cells and increased metastatic potential. Methods Transgenic mice expressing a human catalase gene (mCAT) were crossed with MMTV-PyMT transgenic mice that develop metastatic breast cancer. All mice (33 mCAT positive and 23 mCAT negative) were terminated at 110 days of age, when tumors were well advanced. Tumors were histologically assessed for invasiveness, proliferation and metastatic foci in the lungs. ROS levels and activation status of p38 MAPK were determined. Results PyMT mice expressing mCAT had a 12.5 per cent incidence of high histological grade primary tumor invasiveness compared to a 62.5 per cent incidence in PyMT mice without mCAT. The histological grade correlated with incidence of metastasis with 56 per cent of PyMT mice positive for mCAT showing evidence of pulmonary metastasis compared to 85.4 per cent of PyMT mice negative for mCAT with pulmonary metastasis (p ? 0.05). PyMT tumor cells expressing mCAT had lower ROS levels and were more resistant to hydrogen peroxide-induced oxidative stress than wild type tumor cells, suggesting that mCAT has the potential of quenching intracellular ROS and subsequent invasive behavior. The metastatic tumor burden in PyMT mice expressing mCAT was 0.1 mm2/cm2 of lung tissue compared with 1.3 mm2/cm2 of lung tissue in PyMT mice expressing the wild type allele (p ? 0.01), indicating that mCAT could play a role in mitigating metastatic tumor progression at a distant organ site. Expression of mCAT in the lungs increased resistance to hydrogen peroxide-induced oxidative stress that was associated with decreased activation of p38MAPK suggesting ROS signaling is dependent on p38MAPK for at least some of its downstream effects. Conclusion Targeting catalase within mitochondria of tumor cells and tumor stromal cells suppresses ROS-driven tumor progression and metastasis. Therefore, increasing the antioxidant capacity of the mitochondrial compartment could be a rational therapeutic approach for invasive breast cancer. Please see related commentary article: http://www.biomedcentral.com/1741-7015/9/62 PMID:21605372

  17. [The catalase inhibitor aminotriazole alleviates acute alcoholic liver injury].

    PubMed

    Ai, Qing; Ge, Pu; Dai, Jie; Liang, Tian-Cai; Yang, Qing; Lin, Ling; Zhang, Li

    2015-02-25

    In this study, the effects of catalase (CAT) inhibitor aminotriazole (ATZ) on alcohol-induced acute liver injury were investigated to explore the potential roles of CAT in alcoholic liver injury. Acute liver injury was induced by intraperitoneal injection of alcohol in Sprague Dawley (SD) rats, and various doses of ATZ (100-400 mg/kg) or vehicle were administered intraperitoneally at 30 min before alcohol exposure. After 24 h of alcohol exposure, the levels of aspartate transaminase (AST), alanine transaminase (ALT) and lactate dehydrogenase (LDH) in plasma were determined. The degree of hepatic histopathological abnormality was observed by HE staining. The activity of hepatic CAT, hydrogen peroxide (H?O?) level and malondialdehyde (MDA) content in liver tissue were measured by corresponding kits. The levels of tumor necrosis factor-? (TNF-?) and interleukin-6 (IL-6) in plasma were determined by ELISA method. The results showed that treatment with ATZ dose-dependently suppressed the elevation of ALT, AST and LDH levels induced by alcohol exposure, and that ATZ alleviated alcohol-induced histopathological alterations. Furthermore, ATZ inhibited the activity of CAT, reduced hepatic levels of H?O?and MDA in alcohol exposed rats. ATZ also decreased the levels of plasma TNF-? and IL-6 in rats with alcohol exposure. These results indicated that ATZ attenuated alcohol-induced acute liver injury in rats, suggesting that CAT might play important pathological roles in the pathogenesis of alcoholic liver injury. PMID:25672632

  18. Brain catalase activity is highly correlated with ethanol-induced locomotor activity in mice.

    PubMed

    Correa, M; Sanchis-Segura, C; Aragon, C M

    2001-07-01

    It has been demonstrated that acute administration of lead to mice enhances brain catalase activity and ethanol-induced locomotion. These effects of lead seem to be related, since they show similar time courses and occur at similar doses. In the present study, in an attempt to further evaluate the relation between brain catalase activity and lead-induced changes in ethanol-stimulated locomotion, the interaction between lead acetate and 3-amino-1H,2,4-triazole (AT), a well-known catalase inhibitor, was assessed. In this study, lead acetate or saline was acutely injected intraperitoneally to Swiss mice at doses of 50 or 100 mg/kg 7 days before testing. On the test day, animals received an intraperitoneal injection of AT (0, 10, or 500 mg/kg). Five hours following AT treatment, ethanol (0.0 or 2.5 g/kg, ip) was injected and the animals were placed in open-field chambers, in which locomotion was measured for 10 min. Neither lead exposure nor AT administration, either alone or in combination, had any effect on spontaneous locomotor activity. AT treatment reduced ethanol-induced locomotion as well as brain catalase activity. On the other hand, ambulation and brain catalase activity were significantly increased by both doses of lead. Furthermore, AT significantly reduced the potentiation produced by lead acetate on brain catalase and on ethanol-induced locomotor activity in a dose-dependent manner. A significant correlation was found between locomotion and catalase activity across all test conditions. The results show that brain catalase activity is involved in the effects of lead acetate on ethanol-induced locomotion in mice. Thus, this study confirms the notion that brain catalase provides the molecular basis for understanding some of the mechanisms of the action of ethanol in the central nervous system. PMID:11495670

  19. Effects of pergolide mesylate on transduction efficiency of PEP-1-catalase protein

    SciTech Connect

    Sohn, Eun Jeong; Kim, Dae Won; Kim, Young Nam; Kim, So Mi [Department of Biomedical Science and Research Institute of Bioscience and Biotechnology, Hallym University, Chunchon 200-702 (Korea, Republic of)] [Department of Biomedical Science and Research Institute of Bioscience and Biotechnology, Hallym University, Chunchon 200-702 (Korea, Republic of); Lim, Soon Sung [Department of Food Science and Nutrition and RIC Center, Hallym University, Chunchon 200-702 (Korea, Republic of)] [Department of Food Science and Nutrition and RIC Center, Hallym University, Chunchon 200-702 (Korea, Republic of); Kang, Tae-Cheon [Department of Anatomy and Neurobiology, College of Medicine, Hallym University, Chunchon 200-702 (Korea, Republic of)] [Department of Anatomy and Neurobiology, College of Medicine, Hallym University, Chunchon 200-702 (Korea, Republic of); Kwon, Hyeok Yil [Department of Physiology, College of Medicine, Hallym University, Chunchon 200-702 (Korea, Republic of)] [Department of Physiology, College of Medicine, Hallym University, Chunchon 200-702 (Korea, Republic of); Kim, Duk-Soo [Department of Anatomy, College of Medicine, Soonchunhyang University, Cheonan-Si 330-090 (Korea, Republic of)] [Department of Anatomy, College of Medicine, Soonchunhyang University, Cheonan-Si 330-090 (Korea, Republic of); Cho, Sung-Woo [Department of Biochemistry and Molecular Biology, University of Ulsan College of Medicine, Seoul 138-736 (Korea, Republic of)] [Department of Biochemistry and Molecular Biology, University of Ulsan College of Medicine, Seoul 138-736 (Korea, Republic of); Han, Kyu Hyung; Park, Jinseu; Eum, Won Sik [Department of Biomedical Science and Research Institute of Bioscience and Biotechnology, Hallym University, Chunchon 200-702 (Korea, Republic of)] [Department of Biomedical Science and Research Institute of Bioscience and Biotechnology, Hallym University, Chunchon 200-702 (Korea, Republic of); Hwang, Hyun Sook, E-mail: wazzup@hallym.ac.kr [Department of Biomedical Science and Research Institute of Bioscience and Biotechnology, Hallym University, Chunchon 200-702 (Korea, Republic of); Choi, Soo Young, E-mail: sychoi@hallym.ac.kr [Department of Biomedical Science and Research Institute of Bioscience and Biotechnology, Hallym University, Chunchon 200-702 (Korea, Republic of)

    2011-03-18

    Research highlights: {yields} We studied effects of pergolide mesylate (PM) on in vitro and in vivo transduction of PEP-1-catalase. {yields} PEP-1-catatase inhibited 12-O-tetradecanoylphorbol-13-acetate (TPA)-induced inflammation. {yields} PM enhanced the transduction of PEP-1-catalase into HaCaT cells and skin tissue. {yields} PM increased anti-inflammatory activity of PEP-1-catalase. {yields} PM stimulated therapeutic action of anti-oxidant enzyme catalase in oxidative-related diseases. -- Abstract: The low transduction efficiency of various proteins is an obstacle to their therapeutic application. However, protein transduction domains (PTDs) are well-known for a highly effective tool for exogenous protein delivery to cells. We examined the effects of pergolide mesylate (PM) on the transduction of PEP-1-catalase into HaCaT human keratinocytes and mice skin and on the anti-inflammatory activity of PEP-1-catatase against 12-O-tetradecanoylphorbol-13-acetate (TPA)-induced inflammation using Western blot and histological analysis. PM enhanced the time- and dose-dependent transduction of PEP-1-catalase into HaCaT cells without affecting the cellular toxicity. In a mouse edema model, PEP-1-catalase inhibited the increased expressions of inflammatory mediators and cytokines such as cyclooxygenase-2, inducible nitric oxide synthase, interleukin-6 and -1{beta}, and tumor necrosis factor-{alpha} induced by TPA. On the other hand, PM alone failed to exert any significant anti-inflammatory effects. However, the anti-inflammatory effect of co-treatment with PEP-1-catalase and PM was more potent than that of PEP-1-catalase alone. Our results indicate that PM may enhance the delivery of PTDs fusion therapeutic proteins to target cells and tissues and has potential to increase their therapeutic effects of such drugs against various diseases.

  20. Maturation of Catalase Precursor Proceeds to a Different Extent in Glyoxysomes and Leaf Peroxisomes of Pumpkin Cotyledons

    Microsoft Academic Search

    Junji Yamaguchi; Mikio Nishimura; Takashi Akazawa

    1984-01-01

    As an approach to study the mechanism of the microbody transition (glyoxysomes to leaf peroxisomes) in greening pumpkin cotyledons, catalase molecules were purified from the two different types of microbody and their structural properties were compared. The purified glyoxysomal catalase was found to consist of four identical subunits (55 kDa), whereas the leaf peroxisomal catalase contains two different forms of

  1. Volume84, number 2 FEBS LETTERS December 1977 EFFECTS OF WASHING AND OSMOTIC SHOCK ON CATALASE ACTIVITY OF INTACT

    E-print Network

    Allen, John F.

    Volume84, number 2 FEBS LETTERS December 1977 EFFECTS OF WASHING AND OSMOTIC SHOCK ON CATALASE] ). Since catalase causes release of oxygen from hydrogen peroxide, an enhancement of net oxygen evolution on addition of catalase to illuminated chloroplasts indicates that photosynthetic reduction of oxygen has

  2. MJD05-018 revised version July 22, 2005 1 Association of CAT polymorphisms with catalase activity and

    E-print Network

    Paris-Sud XI, Université de

    MJD05-018 revised version July 22, 2005 1 Association of CAT polymorphisms with catalase activity that catalase activity is modified by CAT single nucleotide polymorphisms (SNPs) (­262 factor (TNF, - 308) in 196 miners. Erythrocyte catalase, superoxide dismutase, and glutathione peroxidase

  3. Comparison of the California Mastitis Test, Catalase Test, and pH Readings on Quarter Milk Samples

    Microsoft Academic Search

    C. T. Raby; P. L. Hubbard; R. H. Cobbins

    1967-01-01

    Three representative groups from 611 quarter samples of aseptically collected milk were compared for catalase, pH, and California mastitis test readings. Statistical analysis (determination of correlation coefficient) was applied to 102 of the 611 quarter samples. It was found that the correlation coefficient for catalase and pH reading was more significant than the correlation coefficient of the catalase and CMT

  4. A synthetic superoxide dismutase/catalase mimetic EUK-207 mitigates radiation dermatitis and promotes wound healing in irradiated rat skin

    PubMed Central

    Doctrow, Susan R.; Lopez, Argelia; Schock, Ashley M.; Duncan, Nathan E.; Jourdan, Megan M.; Olasz, Edit B.; Moulder, John E.; Fish, Brian L.; Mäder, Marylou; Lazar, Jozef; Lazarova, Zelmira

    2012-01-01

    In the event of a radionuclear attack or nuclear accident, the skin would be the first barrier exposed to radiation, though skin injury can progress over days to years following exposure. Chronic oxidative stress has been implicated as being a potential contributor to the progression of delayed radiation-induced injury to skin and other organs. To examine the causative role of oxidative stress in delayed radiation-induced skin injury, including impaired wound healing, we tested a synthetic superoxide dismutase (SOD)/catalase mimetic, EUK-207, in a rat model of combined skin irradiation and wound injury. Administered systemically, beginning 48 h after irradiation, EUK-207 mitigated radiation dermatitis, suppressed indicators of tissue oxidative stress, and enhanced wound healing. Evaluation of gene expression in irradiated skin at 30 days after exposure revealed a significant upregulation of several key genes involved in detoxication of reactive oxygen and nitrogen species. This gene expression pattern was primarily reversed by EUK-207 therapy. These results demonstrate that oxidative stress plays a critical role in the progression of radiation-induced skin injury, and that the injury can be mitigated by appropriate antioxidant compounds administered 48 h after exposure. PMID:23190879

  5. Immobilization of catalase on chitosan and amino acid- modified chitosan beads.

    PubMed

    Ba?ak, Esra; Aydemir, Tülin

    2013-08-01

    Bovine liver catalase was covalently immobilized onto amino acid-modified chitosan beads. The beads were characterized with SEM, FTIR, TGA and the effects of immobilization on optimum pH and temperature, thermostability, reusability were evaluated. Immobilized catalase showed the maximal enzyme activity at pH 7.0 at 30°C. The kinetic parameters, Km and Vmax, for immobilized catalase on alanine-chitosan beads and lysine-chitosan beads were estimated to be 25.67 mM, 27 mM and 201.39 ?mol H2O2/min, 197.50 ?mol H2O2/min, respectively. The activity of the immobilized catalase on Ala-CB and Lys-CB retained 40% of its high initial activity after 100 times of reuse. PMID:23316810

  6. Spectroscopic study on the interaction of catalase with bifendate and analogs

    NASA Astrophysics Data System (ADS)

    Wang, Ruiqiang; Zhang, Lu; Wang, Rui; Dou, Huanjing; Li, Hua; Wang, Yi; Pu, Juanjuan; Wang, Ruiyong

    2013-02-01

    The interactions of bifendate (DDB) or analogs (Bicyclol, I, II and III) with catalase are analyzed by spectrophotometric methods. The fluorescence spectra results show the intrinsic fluorescence of catalase is strongly quenched by DDB or analogs with a static quenching procedure. The binding constants are obtained at three temperatures. The thermodynamics parameters (?H, ?S, ?G) indicate the hydrophobic and electrostatic interactions play a major role in the interaction. The results of synchronous fluorescence, UV-vis absorption and three-dimensional fluorescence spectra demonstrate that the microenvironments of Trp residue of catalase are disturbed by the analogs. Thermodynamic results showed that DDB is the strongest quencher and bind to catalase with the highest affinity among five compounds.

  7. Mycobacterium tuberculosis Catalase and Peroxidase Activities and Resistance to Oxidative Killing in Human Monocytes In Vitro

    Microsoft Academic Search

    CLAUDIA MANCA; SIMON PAUL; CLIFTON E. BARRY; VICTORIA H. FREEDMAN; GILLA KAPLAN

    1999-01-01

    Mycobacterium tuberculosis has a relatively high resistance to killing by hydrogen peroxide and organic peroxides. Resistance may be mediated by mycobacterial catalase-peroxidase (KatG) and possibly by alkyl hydroperoxide reductase (AhpC). To determine the interrelationship between sensitivity to H2O2, catalase and peroxidase activities, and bacillary growth rates measured both intracellularly in human monocytes and in culture medium, we examined one laboratory

  8. Purification, characterization, and identification of a novel bifunctional catalase-phenol oxidase from Scytalidium thermophilum

    Microsoft Academic Search

    Didem Sutay Kocabas; Ufuk Bakir; Simon E. V. Phillips; Michael J. McPherson; Zumrut B. Ogel

    2008-01-01

    A novel bifunctional catalase with an additional phenol oxidase activity was isolated from a thermophilic fungus, Scytalidium thermophilum. This extracellular enzyme was purified ca. 10-fold with 46% yield and was biochemically characterized. The enzyme contains\\u000a heme and has a molecular weight of 320 kDa with four 80 kDa subunits and an isoelectric point of 5.0. Catalase and phenol\\u000a oxidase activities were most

  9. Adventitial gene transfer of catalase attenuates angiotensin II-induced vascular remodeling

    PubMed Central

    LIU, CUN-FEI; ZHANG, JIA; SHEN, KAI; GAO, PING-JIN; WANG, HAI-YA; JIN, XIN; MENG, CHAO; FANG, NING-YUAN

    2015-01-01

    Vascular adventitia and adventitia-derived reactive oxygen species (ROS) contribute to vascular remodeling following vascular injury. A previous ex vivo study in adventitial fibroblasts showed that catalase, one of most important anti-oxide enzymes, was downregulated by angiotensin II (AngII). The aim of the present study was to investigate whether adventitial gene transfer of catalase affects AngII-induced vascular remodeling in vivo. Adenoviruses co-expressing catalase and enhanced green fluorescent protein (eGFP) or expressing eGFP only were applied to the adventitial surface of common carotid arteries of Sprague-Dawley rats. Alzet minipumps administering AngII (0.75 mg/kg/day) were then implanted subcutaneously for 14 days. Systolic blood pressure and biological parameters of vascular remodeling were measured in each group. Adventitial fibroblasts were cultured and p38 mitogen-activated protein kinase (MAPK) phosphorylation was measured using western blot analysis. The results showed that adventitial gene transfer of catalase had no effect on AngII-induced systolic blood pressure elevation. However, catalase adenovirus transfection significantly inhibited AngII-induced media hypertrophy compared with that of the control virus (P<0.05). In addition, catalase transfection significantly attenuated AngII-induced ROS generation, macrophage infiltration, collagen deposition and adventitial ?-smooth muscle actin expression. Furthermore, catalase transfection significantly inhibited the AngII-induced increase in p38MAPK phosphorylation. In conclusion, the results of the present study demonstrated that adventitial gene transfer of catalase significantly attenuated AngII-induced vascular remodeling in rats via inhibition of adventitial p38MAPK phosphorylation. PMID:25503998

  10. Nitric oxide inhibits pulmonary artery catalase and H2O2-associated relaxation.

    PubMed

    Mohazzab-H, K M; Fayngersh, R P; Wolin, M S

    1996-11-01

    Our previous studies on the mechanism of relaxation of calf pulmonary arteries to H2O2 detected a role for increased formation of guanosine-3',5'-cyclic monophosphate as a result of a catalase-elicited activation of soluble guanylate cyclase. We have also shown that lactate elicits relaxation through increasing H2O2 produced from NADH oxidase-derived superoxide anion (O2-.). Because nitric oxide (NO) is a potential inhibitor of catalase, we examined the effects of exposure of endothelium-denuded bovine calf pulmonary arteries to an elevated physiological level of NO on relaxation to H2O2 and lactate. Treatment of pulmonary arteries with approximately 50 nM of NO gas for 2 min caused a subsequent inhibition of relaxation to H2O2 (10(-6) to 10(-3)M) and lactate (1-10 mM), without markedly altering relaxation responses to S-nitroso-N-acetylpenicillamine (10(-9) to 10(-6) M) or isoproterenol (10(-9) to 10(-6) M). This NO exposure caused a 63 and 70% inhibition of the metabolism by smooth muscle catalase of both endogenously produced and exogenous (100 microM) H2O2, respectively, as measured by the H2O2-dependent cooxidation of methanol to formaldehyde. A similar treatment of purified catalase with NO caused subsequent inhibition of its ability to metabolize H2O2, associated with changes in the spectra of catalase (increases in the absorbance at 535 and 570 nm) to a species that resembled compound II, an inactive form of catalase. The exposure of pulmonary arteries to NO also resulted in the detection of H2O2 release (by catalase-inhibitable luminol/ peroxidase-chemiluminescence). Thus exposure of pulmonary arteries to increased physiological levels of NO may promote altered vasoactive responses involving H2O2 as a result of the inhibition of catalase. PMID:8945907

  11. Redundant Catalases Detoxify Phagocyte Reactive Oxygen and Facilitate Histoplasma capsulatum Pathogenesis

    PubMed Central

    Holbrook, Eric D.; Smolnycki, Katherine A.; Youseff, Brian H.

    2013-01-01

    Histoplasma capsulatum is a respiratory pathogen that infects phagocytic cells. The mechanisms allowing Histoplasma to overcome toxic reactive oxygen molecules produced by the innate immune system are an integral part of Histoplasma's ability to survive during infection. To probe the contribution of Histoplasma catalases in oxidative stress defense, we created and analyzed the virulence defects of mutants lacking CatB and CatP, which are responsible for extracellular and intracellular catalase activities, respectively. Both CatB and CatP protected Histoplasma from peroxide challenge in vitro and from antimicrobial reactive oxygen produced by human neutrophils and activated macrophages. Optimal protection required both catalases, as the survival of a double mutant lacking both CatB and CatP was lower than that of single-catalase-deficient cells. Although CatB contributed to reactive oxygen species defenses in vitro, CatB was dispensable for lung infection and extrapulmonary dissemination in vivo. Loss of CatB from a strain also lacking superoxide dismutase (Sod3) did not further reduce the survival of Histoplasma yeasts. Nevertheless, some catalase function was required for pathogenesis since simultaneous loss of both CatB and CatP attenuated Histoplasma virulence in vivo. These results demonstrate that Histoplasma's dual catalases comprise a system that enables Histoplasma to efficiently overcome the reactive oxygen produced by the innate immune system. PMID:23589579

  12. Purification and Characterization of a Novel Thermo-Alkali-Stable Catalase from Thermus brockianus

    SciTech Connect

    Thompson, Vicki Sue; Schaller, Kastli Dianne; Apel, William Arnold

    2003-10-01

    A novel thermo-alkali-stable catalase from Thermus brockianus was purified and characterized. The protein was purified from a T. brockianus cell extract in a three-step procedure that resulted in 65-fold purification to a specific activity of 5300 U/mg. The enzyme consisted of four identical subunits of 42.5 kDa as determined by SDS-PAGE and a total molecular mass measured by gel filtration of 178 kDa. The catalase was active over a temperature range from 30 to 94 C and a pH range from 6 to 10, with optimum activity occurring at 90 C and pH 8. At pH 8, the enzyme was extremely stable at elevated temperatures with half-lives of 330 h at 80 C and 3 h at 90 C. The enzyme also demonstrated excellent stability at 70 C and alkaline pH with measured half-lives of 510 h and 360 h at pHs of 9 and 10, respectively. The enzyme had an unusual pyridine hemochrome spectrum and appears to utilize eight molecules of heme c per tetramer rather than protoheme IX present in the majority of catalases studied to date. The absorption spectrum suggested that the heme iron of the catalase was in a 6-coordinate low spin state rather than the typical 5-coordinate high spin state. A Km of 35.5 mM and a Vmax of 20.3 mM/min·mg protein for hydrogen peroxide was measured, and the enzyme was not inhibited by hydrogen peroxide at concentrations up to 450 mM. The enzyme was strongly inhibited by cyanide and the traditional catalase inhibitor 3-amino-1,2,4-triazole. The enzyme also showed no peroxidase activity to peroxidase substrates o-dianisidine and 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid), a trait of typical monofunctional catalases. However, unlike traditional monofunctional catalases, the T. brockianus catalase was easily reduced by dithionite, a characteristic of catalase-peroxidases. The above properties indicate that this catalase has potential for applications in industrial bleaching processes to remove residual hydrogen peroxide from process streams.

  13. Adeno-Associated Viral-Mediated Catalase Expression Suppresses Optic Neuritis in Experimental Allergic Encephalomyelitis

    NASA Astrophysics Data System (ADS)

    Guy, John; Qi, Xiaoping; Hauswirth, William W.

    1998-11-01

    Suppression of oxidative injury by viral-mediated transfer of the human catalase gene was tested in the optic nerves of animals with experimental allergic encephalomyelitis (EAE). EAE is an inflammatory autoimmune disorder of primary central nervous system demyelination that has been frequently used as an animal model for the human disease multiple sclerosis (MS). The optic nerve is a frequent site of involvement common to both EAE and MS. Recombinant adeno-associated virus containing the human gene for catalase was injected over the right optic nerve heads of SJL/J mice that were simultaneously sensitized for EAE. After 1 month, cell-specific catalase activity, evaluated by quantitation of catalase immunogold, was increased approximately 2-fold each in endothelia, oligodendroglia, astrocytes, and axons of the optic nerve. Effects of catalase on the histologic lesions of EAE were measured by computerized analysis of the myelin sheath area (for demyelination), optic disc area (for optic nerve head swelling), extent of the cellular infiltrate, extravasated serum albumin labeled by immunogold (for blood-brain barrier disruption), and in vivo H2O2 reaction product. Relative to control, contralateral optic nerves injected with the recombinant virus without a therapeutic gene, catalase gene inoculation reduced demyelination by 38%, optic nerve head swelling by 29%, cellular infiltration by 34%, disruption of the blood-brain barrier by 64%, and in vivo levels of H2O2 by 61%. Because the efficacy of potential treatments for MS are usually initially tested in the EAE animal model, this study suggests that catalase gene delivery by using viral vectors may be a therapeutic strategy for suppression of MS.

  14. Catalase HPII from Escherichia coli Exhibits Enhanced Resistance to Denaturation Jacek Switala, Joe O. O'Neil, and Peter C. Loewen*,

    E-print Network

    O'Neil, Joe

    Catalase HPII from Escherichia coli Exhibits Enhanced Resistance to Denaturation Jacek Switala, Joe 11, 1999 ABSTRACT: Catalase HPII from Escherichia coli is a homotetramer of 753 residue subunits of the enzyme. For comparison, catalase-peroxidase HPI of E. coli and bovine liver catalase are 50% inactivated

  15. Tumour suppressor PTEN enhanced enzyme activity of GPx, SOD and catalase by suppression of PI3K/AKT pathway in non-small cell lung cancer cell lines.

    PubMed

    Akca, Hakan; Demiray, Aydin; Aslan, Mutay; Acikbas, Ibrahim; Tokgun, Onur

    2013-06-01

    Phosphates and tensin homologue deleted on chromosome 10 (PTEN) is a tumour suppressor gene which dephosphorilates phosphoinositol 3,4,5 triphosphates. Therefore PTEN can regulate PI3K/AKT pathway in cells. Because of promoter methylation or gene deletion, PTEN expression is commonly decreased or lost in non-small cell lung cancer (NSCLC) cell lines. Therefore, we hypothesized that PTEN could regulate the activity of superoxide dismutase (CuZnSOD), glutathione peroxidase (GPx) and catalase. We first recreated PTENwt, G129R and G129E expressions in lung cell lines, in which endogenous PTEN expression was not detected. Then, we showed that PTEN could suppress AKT activity by its lipid phosphatase domain. We then examined the effect of recreated PTEN expressions in NSCLC cells. While PTENwt expression caused enhanced activity of SOD, GPx and catalase in transfected cells lines, neither G129R nor G129E expression effected enzyme activities. These results suggest that PTEN can up-regulate SOD, GPx and catalase activity by inhibition of PI3K/AKT pathway in NSCLC cell lines. PMID:22299584

  16. Immobilization and kinetics of catalase on calcium carbonate nanoparticles attached epoxy support.

    PubMed

    Preety; Hooda, Vinita

    2014-01-01

    A novel hybrid epoxy/nano CaCO3 composite matrix for catalase immobilization was prepared by polymerizing epoxy resin in the presence of CaCO3 nanoparticles. The hybrid support was characterized using scanning electron microscopy and Fourier transform infrared spectroscopy. Catalase was successfully immobilized onto epoxy/nano CaCO3 support with a conjugation yield of 0.67 ± 0.01 mg/cm(2) and 92.63 ± 0.80 % retention of activity. Optimum pH and optimum temperature of free and immobilized catalases were found to be 7.0 and 35 °C. The value of Km for H2O2 was higher for immobilized enzyme (31.42 mM) than native enzyme (27.73 mM). A decrease in Vmax value from 1,500 to 421.10 ?mol (min mg protein)(-1) was observed after immobilization. Thermal and storage stabilities of catalase improved immensely after immobilization. Immobilized enzyme retained three times than the activity of free enzyme when kept at 75 °C for 1 h and the half-life of enzyme increased five times when stored in phosphate buffer (0.01 M, pH 7.0) at 5 °C. The enzyme could be reused 30 times without any significant loss of its initial activity. Desorption of catalase from the hybrid support was minimum at pH 7.0. PMID:24048961

  17. Effect of Catalase and Sodium Fluoride on Human Enamel bleached with 35% Carbamide Peroxide

    PubMed Central

    Shigli, Anand L; Sharma, Divya S; Thakur, Gagan

    2015-01-01

    ABSTRACT Aim: To evaluate the effects of postbleaching antioxidant application fluoridation treatment on the surface morphology and microhardness of human enamel. Materials and methods: Ten freshly extracted human maxillary central incisors were cut at cementoenamel junction. Crown portion was sectioned into six slabs which were divided into five groups: group A – untreated controls; group B – 35% carbamide peroxide (CP); group C – 35% CP and catalase; group D – treatment with 35% CP and 5% sodium fluoride; group E – 35% CP, catalase and 5% sodium fluoride. Thirty-five percent carbamide peroxide application included two applications of 30 minutes each at a 5-day interval. After treatment, the slabs were thoroughly washed with water for 10 seconds and stored in artificial saliva at 37°C until the next treatment. Two percent sodium fluoride included application for 5 minutes. Three catalase included application for 3 minutes. Results: After 5 days, groups B and C showed significantly decreased enamel microhardness compared to control. Group D specimens showed relatively less reduction in enamel micro-hardness than group C specimens. There is a marked increase in enamel microhardness in group E specimens. Conclusions: Fluoride take up was comparatively enhanced after catalase application resulting in less demineralization and increased microhardness. How to cite this article: Thakur R, Shigli AL, Sharma DS, Thakur G. Effect of Catalase and Sodium Fluoride on Human Enamel bleached with 35% Carbamide Peroxide. Int J Clin Pediatr Dent 2015;8(1):12-17.

  18. Development of a new catalase activity assay for biological samples using optical CUPRAC sensor.

    PubMed

    Bekde?er, Burcu; Özyürek, Mustafa; Güçlü, Kubilay; Alkan, Fulya Üstün; Apak, Re?at

    2014-11-11

    A novel catalase activity assay was developed for biological samples (liver and kidney tissue homogenates) using a rapid and low-cost optical sensor-based 'cupric reducing antioxidant capacity' (CUPRAC) method. The reagent, copper(II)-neocuproine (Cu(II)-Nc) complex, was immobilized onto a cation-exchanger film of Nafion, and the absorbance changes associated with the formation of the highly-colored Cu(I)-Nc chelate as a result of reaction with hydrogen peroxide (H2O2) was measured at 450 nm. When catalase was absent, H2O2 produced the CUPRAC chromophore, whereas catalase, being an effective H2O2 scavenger, completely annihilated the CUPRAC signal due to H2O2. Thus, the CUPRAC absorbance due to H2O2 oxidation concomitant with Cu(I)-Nc formation decreased proportionally with catalase. The developed sensor gave a linear response over a wide concentration range of H2O2 (0.68-78.6 ?M). This optical sensor-based method applicable to tissue homogenates proved to be efficient for low hydrogen peroxide concentrations (physiological and nontoxic levels) to which the widely used UV method is not accurately responsive. Thus, conventional problems of the UV method arising from relatively low sensitivity and selectivity, and absorbance disturbance due to gaseous oxygen evolution were overcome. The catalase findings of the proposed method for tissue homogenates were statistically alike with those of HPLC. PMID:24887508

  19. The oxidation of chiral alcohols catalyzed by catalase in organic solvents

    SciTech Connect

    Magner, E.; Klibanov, A.M. [Massachusetts Inst. of Tech., Cambridge, MA (United States). Dept. of Chemistry

    1995-04-20

    The catalytic properties of bovine liver catalase have been investigated in organic solvents. In tetrahydrofuran, dioxane, and acetone (all containing 1% to 3% of water), the enzyme breaks down tert-butyl hydroperoxide several fold faster than in pure water. Furthermore, the rate of catalase-catalyzed production of tert-butanol from tert-butyl hydroperoxide increases more than 400-fold upon transition from aqueous buffer to ethanol as the reaction medium. The mechanistic rationale for this striking effect is that in aqueous buffer the rate-limiting step of the enzymatic process involves the reduction of catalase`s compound 1 by tert-butyl hydroperoxide. In ethanol, an additional step in the reaction scheme becomes available in which ethanol, greatly outcompeting the hydroperoxide, is oxidized by compound 1 regenerating the free enzyme. In solvents, such as acetonitrile or tetrahydrofuran, which themselves are not oxidizable by compound 1, catalase catalyzes the oxidation of numerous primary and secondary alcohols with tert-butyl hydroperoxide to the corresponding aldehydes or ketones. The enzymatic oxidation of some chiral alcohols (2,3-butanediol, citronellol, and menthol) under these conditions occurs enantioselectively. Examination of the enantioselectivity for the oxidation of 2,3-butanediol in a series of organic solvents reveals a considerable solvent dependence.

  20. Relationship between uptake of mercury vapor by mushrooms and its catalase activity

    SciTech Connect

    Ogata, M.; Kenmotsu, K.; Hirota, N.; Naito, M.

    1981-12-01

    The uptake of mercury vapor by mushrooms (Shiitake) artifically grown on an oak tree and the uptake in vitro by catalase extracts prepared from mushroom Hay Bacillus and spinach are reported. Mushrooms were exposed to 1.4 mg/Hg/cu m for 11 days. Measurement of total mercury was as previously described (Ogata et al. 1978, 1979). Levels in mushrooms ranged from 0.4 +/- 0.1 ..mu..g/g at 0.5 days to 4.6 +/- 0.2 ..mu..g/g at 10.5 days and steady-state thereafter. In in vitro studies Hy uptake by mushroom catalase extract was estimated by the perborate method. Uptake was found to parallel catalase activity and was inhibited by potassium cyanide, sodium azide, and 3-amino-1,2,4-triazole. Similar results were obtained with Hay Bacillus and spinach catalase extracts. Results suggest that the level of mercury in the mushroom can be used as an indicator of mercury pollution in the environment. It is also suggested that catalase has an important role in uptake of mercury vapor in the plant. 2 tables (JMT)

  1. Effects of estrogen on glutathione and catalase levels in human erythrocyte during menstrual cycle

    PubMed Central

    SHENG-HUANG, CHANG; CHIEH-HSIN, CHANG; MU-CHUN, YANG; WEN-TUNG, HSU; CHIA-YING, HSIEH; YA-TING, HUNG; WAN-LING, SU; JIUAN-JEN, SHIU; CHIH-YANG, HUANG; JER-YUH, LIU

    2015-01-01

    The present study evaluated the effects of physiological serum estrogen during the menstrual cycle on glutathione (GSH) and catalase activities. The sample included 43 healthy females between the ages of 22 and 51 years. The subjects were divided into two groups according to the stage of the menstrual cycle. Group A consisted of 16 samples extracted between days 10 and 20 from the first day of menstruation when estrogen levels were considered to be at their highest. Group B consisted of 27 samples extracted during other times of the estimated 30 days of menstruation. Data showed that the estrogen level in group A (184±106 pg/ml) was higher than that in group B (105±56 pg/ml) (P<0.01). The GSH and catalase levels in group A (4.4±2.3 µg/mg and 210±72 IU/mg, respectively) were also significantly higher compared to the levels in group B (3.2±1.8 µg/mg and 168±62 IU/mg, respectively) (P <0.05). Spearman's rank correlation showed that the expression of catalase in red blood cells significantly correlated with serum estrogen level but not with GSH. However, the changes in estrogen plasma levels, erythrocyte GSH level and catalase activity suggested that the consumption of GSH and catalase in erythrocyte during the menstrual cycle may be associated with the level of estrogen present in the bloodstream. PMID:25798250

  2. Arrhenius activation energy of damage to catalase during spray-drying.

    PubMed

    Schaefer, Joachim; Lee, Geoffrey

    2015-07-15

    The inactivation of catalase during spray-drying over a range of outlet gas temperatures could be closely represented by the Arrhenius equation. From this an activation energy for damage to the catalase could be calculated. The close fit to Arrhenius suggests that the thermally-induced part of inactivation of the catalase during the complex drying and particle-formation processes takes place at constant temperature. These processes are rapid compared with the residence time of the powder in the collecting vessel of the cyclone where dried catalase is exposed to a constant temperature equal to approximately the drying gas outlet temperature. A lower activation energy after spray drying with the ultrasonic nozzle was found than with the 2-fluid nozzle under otherwise identical spray drying conditions. It is feasible that the ultrasonic nozzle when mounted in the lid of the spray dryer heats up toward the drying gas inlet temperature much more that the air-cooled 2-fluid nozzle. Calculation of the Arrhenius activation energy also showed how the stabilizing efficacy of trehalose and mannitol on the catalase varies in strength across the range of drying gas inlet and outlet temperatures examined. PMID:25940040

  3. Effect of cimetidine on catalase activity of Pseudomonas aeruginosa: a suggested mechanism of action.

    PubMed

    Masoud, Masoudeh; Ebrahimi, Farnoosh; Minai-Tehrani, Dariush

    2014-01-01

    Catalase is an important enzyme for the degradation of hydrogen peroxide in cells. Bacteria have potent catalase to deal with H2O2 in their medium culture. Any chemicals that inhibit catalase activity can be harmful for cells. Histamine H2 antagonist drugs such as cimetidine and ranitidine are used for the treatment of gastrointestinal tract disorders. The present results showed that cimetidine could inhibit the catalase activity of Pseudomonas aeruginosa in a competitive inhibition. The determination of IC50 value and Ki (6.5 ?M) of cimetidine demonstrated that the enzyme binds to the drug with high affinity. Binding of the drug to the enzyme was pH-dependent and no binding was observed at basic pH (>9) and acidic pH (<6). Moreover, the imidazole ring and cyanoguanidine group of cimetidine may play an important role in inhibition by binding to Fe in heme group and glutamic acid 51 residue on the enzyme, respectively. Ranitidine had no effect on the catalase activity. PMID:24993120

  4. Catalase is a sink for H2O2 and is indispensable for stress defence in C3 plants

    Microsoft Academic Search

    Hilde Willekens; Sangpen Chamnongpol; Mark Davey; Martina Schraudner; Christian Langebartels; Dirk Inzé; Wim Van Camp; Marc Van Montagu

    1997-01-01

    Hydrogen peroxide (H2O2) has been implicated in many stress conditions. Control of H2O2 levels is complex and dissection of mechanisms generating and relieving H2O2 stress is difficult, particularly in intact plants. We have used transgenic tobacco with ?10% wild-type catalase activity to study the role of catalase and effects of H2O2 stress in plants. Catalase-deficient plants showed no visible disorders

  5. Enzymatic exploration of catalase from a nanoparticle producing and biodecolorizing algae Shewanella xiamenensis BC01.

    PubMed

    Ng, I-Son; Xu, Fangxin; Zhang, Xia; Ye, Chiming

    2015-05-01

    Shewanella xiamenensis (SXM) was found to produce nanoparticles (NPs) under aerobic condition. The oxidoreductase enzymatic activities including of catalase, manganese peroxidase, laccase, NADH dehydrogenase, flavin reductase, azoreductase and Fe reductase are first investigated. Catalase showed the greatest enzymatic activity among all oxidoreductases in SXM, which with strong activities in multiple substrates of ABTS, guaiacol and 2,6-DMP. The optimum temperature, pH, concentrations of H2O2 and 2,6-DMP for this enzyme were found to be 65 °C, pH 4.0, 128.7 mM and 10 mM, respectively. Finally, from the kinetic parameters and structure simulation of catalase, implied that SXM would potentially apply in bioremediation, microbe fuel cells (MFCs) and nano-biotechnology based on its distinguished enzymatic system. PMID:25306444

  6. The functionalization of saturated hydrocarbons. Part 35. On the intermediates in an Fe III catalase model in pyridine. Relevance to the catalase enzyme

    Microsoft Academic Search

    Derek H. R. Barton; Bin Hu

    1996-01-01

    Ferric chloride in pyridine behaves as an efficient model for the catalase enzyme. It converts H2O2 nearly quantitatively into water and oxygen (2 H2O2 ? 2 H2O + O2). The addition of Ph2S to the model system affords Ph2SO, the amount of which increases with the Ph2S added. The inverse relationship between oxygen and Ph2SO formation proves that there is

  7. Subchronic exposure to high-dose ACE-inhibitor moexipril induces catalase activity in rat liver.

    PubMed

    Adeghate, E; Hasan, M Y; Ponery, A S; Nurulain, S M; Petroianu, G A

    2005-12-01

    The long-term clinical effects of ACE-inhibitors have similarities with those of both fibrates and glitazones, activators of peroxisome proliferator activator receptor (PPAR) alpha and gamma, respectively. The antioxidant enzyme catalase, a heme protein that degrades hydrogen peroxide, is found at high concentrations in peroxisomes. Catalase activity is one of the recognized surrogate markers indicative of PPAR activation in the rat liver. The purpose of the study was to establish the effect of moexipril on catalase activity and to compare it with the effect of both saline controls and that of the known PPAR agonist clofibrate (positive control). Three groups of seven rats were used. All substances were applied i.p. daily for 5 days, followed by a 2-day break. The cycle was repeated eight times. After the final cycle (day 56) the animals were sacrificed and liver tissue collected. The number of catalase positive cells in both moexipril group (95% CI 57-61) and clofibrate group (95% CI 72-80) is higher than in controls (95% CI 3-16) (p < or = 0.01). The number of catalase positive cells in the clofibrate group is higher than in the moexipril group (p < or = 0.01). High-dose subchronic exposure to the ACE-inhibitor moexipril induces catalase activity in the rat liver to an extent comparable to fibrates. We suggest that some of the long-term advantages of ACE inhibitor use - beyond mere BP lowering - might be due to a PPAR mediated effect. PMID:16311918

  8. Genotype???activity relationship for Mn-superoxide dismutase, glutathione peroxidase 1 and catalase in humans

    Microsoft Academic Search

    Maria Bastaki; Karen Huen; Paolo Manzanillo; Neha Chande; Connie Chen; John R. Balmes; Ira B. Tager; Nina Holland

    2006-01-01

    Results Minor allele frequencies ranged from 13% for catalase (T) to 18% for GPX1 (T), and 33% for MnSOD(C) with significant variation between ethnicities. Median GPX1 activity was 13.2U\\/g Hb with a six-fold difference between lowest and highest levels. Catalase activity ranged eight-fold (median: 86.3k\\/g Hb), while median MnSOD activity was 2.8U\\/mg Hb with a 56-fold range of values. MnSOD

  9. Catalase activity as a potential indicator of the reducer component of small closed ecosystems

    NASA Astrophysics Data System (ADS)

    Sarangova, A. B.; Somova, L. A.; Pisman, T. I.

    1997-01-01

    Dynamics of catalase activity has been shown to reflect the growth curve of microorganisms in batch cultivation (celluloselythic bacteria Bacillus acidocaldarius and bacteria of the associated microflora Chlorella vulgaris). Gas and substrate closure of the three component ecosystems with spatially separated components ``producer-consumer-reducer'' (Chl. vulgaris-Paramecium caudatum-B. acidocaldarius, two bacterial strains isolated from the associated microflora Chl. vulgaris) demonstrated that the functioning of the reducer component can be estimated by the catalase activity of microorganisms of this component.

  10. A facile method for improving the covalent crosslinking adsorption process of catalase immobilization.

    PubMed

    Ran, Jingyu; Jia, Shaoyi; Liu, Yong; Zhang, Wei; Wu, Songhai; Pan, Xiaolei

    2010-08-01

    In this paper, we introduced a polydiol (mixture of 1,2-propanediol, 1,3-propanediol, and 2,3-butanediol) to improve the covalent crosslinking adsorption process of immobilized catalase onto chitosan beads. The adsorption behavior was investigated by means of adsorption kinetics and adsorption isotherm. The protein content in crosslinking agent required for approximately 45 min to reach the relative equilibrium, and the protein content in solution of the control group and the pretreated group were 6.63 microg/mL and 6.20 microg/mL, respectively. The maximum catalase adsorption capacity of the control group and the pretreated group were observed as 23.118 microg/g and 25.688 microg/g at pH 7.0, respectively. Temperature profiles showed that 40 degrees C was the ideal temperature for active domain of catalase, and the relative activity of pretreated group was 1.12 times higher than that of the control group. The K(m) value of the control group (67 mM) was higher than that of the pretreated group (54 mM). Thermal stability, operational stability, and the effect of surfactant on catalase adsorption were also explored in this study. PMID:20362437

  11. Immobilized glucose oxidase--catalase and their deactivation in a differential-bed loop reactor.

    PubMed

    Prenosil, J E

    1979-01-01

    Glucose oxidase containing catalase was immobilized with a copolymer of phenylenediamine and glutaraldehyde on pumice and titania carrier to study the enzymatic oxidation of glucose in a differential-bed loop reactor. The reaction rate was found to be first order with respect to the concentration of limiting oxygen substrate, suggesting a strong external mass-transfer resistance for all the flow rates used. The partial pressure of oxygen was varied from 21.3 up to 202.6 kPa. The use of a differential-bed loop reactor for the determination of the active enzyme concentration in the catalyst with negligible internal pore diffusion resistance is shown. Catalyst deactivation was studied, especially with respect to the presence of catalase. It is believed that the hydrogen peroxide formed in the oxidation reaction deactivates catalase first; if an excess of catalase is present, the deactivation of glucose oxidase remains small. The mathematical model subsequently developed adequately describes the experimental results. PMID:427262

  12. Catalase C-262T polymorphism and risk of prostate cancer: evidence from meta-analysis.

    PubMed

    Hu, Jieping; Feng, Fupeng; Zhu, Shimiao; Sun, Libin; Li, Gang; Jiang, Ning; Shang, Zhiqun; Niu, Yuanjie

    2015-03-10

    Catalase is an important endogenous antioxidant enzyme that detoxifies hydrogen peroxide to oxygen and water, thus limiting the deleterious effects of reactive oxygen species. Several studies investigated the role of the Catalase (CAT) C-262T gene polymorphism on the risk of prostate cancer (PCa), but get conflicting results. We performed a meta-analysis based on five studies, to determine whether Catalase C-262T polymorphism contributes to the risk of prostate cancer using odds ratios (OR) with 95% confidence intervals (CI). On the whole, our evidence indicates that CAT C-262T polymorphism significantly increases PCa risk in the allele comparison model (OR=1.094, 95% CI=1.015-1.178, P=0.018). In the stratified analysis by ethnicity, the same results are found among Caucasians (allele model, OR=1.090, 95% CI=1.009-1.177, P=0.028, dominant model, OR=1.108, 95% CI=1.023-1.201, P=0.012, recessive model, OR=1.379, 95% CI=1.158-1.641, P=0.000, homozygous model, OR=1.429, 95% CI=1.196-1.707, P=0.000, and heterozygote model, OR=1.224, 95% CI=1.020-1.469, P=0.030). In conclusion, this meta-analysis suggests a positive correlation between Catalase C-262T polymorphism and the development of PCa. PMID:25576221

  13. Protective role of extracellular catalase (KatA) against UVA radiation in Pseudomonas aeruginosa biofilms.

    PubMed

    Pezzoni, Magdalena; Pizarro, Ramón A; Costa, Cristina S

    2014-02-01

    One of the more stressful factors that Pseudomonas aeruginosa must face in nature is solar UVA radiation. In this study, the protective role of KatA catalase in both planktonic cells and biofilms of P. aeruginosa against UVA radiation was determined by using the wild-type (PAO1) and an isogenic catalase deficient strain (katA). The katA strain was more sensitive than the wild-type, especially in the case of biofilms. Moreover, the wild-type biofilm was more resistant than its planktonic counterpart, but this was not observed in the katA strain. Striking KatA activity was detected in the matrix of katA(+) strains, and to our knowledge, this is the first report of this activity in the matrix of P. aeruginosa biofilms. Provision of bovine catalase or KatA to the matrix of a katA biofilm significantly increased its UVA tolerance, demonstrating that extracellular KatA is essential to optimal defense against UVA in P. aeruginosa biofilms. Efficiency of photocatalytic treatments using TiO2 and UVA was lower in biofilms than in planktonic cells, but KatA and KatB catalases seem not to be responsible for the higher resistance of the sessile cells to this treatment. PMID:24491420

  14. Occurrence, phylogeny, structure, and function of catalases and peroxidases in cyanobacteria.

    PubMed

    Bernroitner, Margit; Zamocky, Marcel; Furtmüller, Paul G; Peschek, Günter A; Obinger, Christian

    2009-01-01

    Cyanobacteria have evolved approximately 3x10(9) years ago from ancient phototrophic microorganisms that already lived on our planet Earth. By opening the era of an aerobic, oxygen-containing biosphere, they are the true pacemakers of geological and biological evolution. Cyanobacteria must have been among the first organisms to elaborate mechanisms for the detoxification of partially reduced oxygen species including (hydrogen) peroxide. Since there is still an suprising lack of knowledge on the type, role, and mechanism(s) of peroxide-degrading enzymes in these bacteria, all 44 fully or partially sequenced genomes for haem and non-haem catalases and peroxidases have been critically analysed based on well known structure-function relationships of the corresponding oxidoreductases. It is demonstrated that H(2)O(2)-dismutating enzymes are mainly represented by bifunctional (haem) catalase-peroxidases and (binuclear) manganese catalases, with the latter being almost exclusively found in diazotrophic species. Several strains even lack a gene that encodes an enzyme with catalase activity. Two groups of peroxidases are found. Genes encoding putative (primordial) haem peroxidases (with homology to corresponding mammalian enzymes) and vanadium-containing iodoperoxidases are found only in a few species, whereas genes encoding peroxiredoxins (1-Cys, 2-Cys, type II, and Q-type) are ubiquitous in cyanobacteria. In addition, approximately 70% contain NADPH-dependent glutathione peroxidase-like proteins. The occurrence and phylogeny of these enzymes is discussed, as well as the present knowledge of their physiological role(s). PMID:19129167

  15. Hydrogen peroxide homeostasis: activation of plant catalase by calcium/calmodulin

    NASA Technical Reports Server (NTRS)

    Yang, T.; Poovaiah, B. W.

    2002-01-01

    Environmental stimuli such as UV, pathogen attack, and gravity can induce rapid changes in hydrogen peroxide (H(2)O(2)) levels, leading to a variety of physiological responses in plants. Catalase, which is involved in the degradation of H(2)O(2) into water and oxygen, is the major H(2)O(2)-scavenging enzyme in all aerobic organisms. A close interaction exists between intracellular H(2)O(2) and cytosolic calcium in response to biotic and abiotic stresses. Studies indicate that an increase in cytosolic calcium boosts the generation of H(2)O(2). Here we report that calmodulin (CaM), a ubiquitous calcium-binding protein, binds to and activates some plant catalases in the presence of calcium, but calcium/CaM does not have any effect on bacterial, fungal, bovine, or human catalase. These results document that calcium/CaM can down-regulate H(2)O(2) levels in plants by stimulating the catalytic activity of plant catalase. Furthermore, these results provide evidence indicating that calcium has dual functions in regulating H(2)O(2) homeostasis, which in turn influences redox signaling in response to environmental signals in plants.

  16. Catalase and glutathione peroxidase are equally active in detoxification of hydrogen peroxide in human erythrocytes

    SciTech Connect

    Gaetani, G.F.; Galiano, S.; Canepa, L.; Ferraris, A.M.; Kirkman, H.N.

    1989-01-01

    Genetic deficiencies of glucose-6-phosphate dehydrogenase (G6PD) and NADPH predispose affected erythrocytes to destruction from peroxides. Conversely, genetic deficiencies of catalase do not predispose affected erythrocytes to peroxide-induced destruction. These observations have served to strengthen the assumption that the NADPH/glutathione/glutathione peroxidase pathway is the principal means for disposal of H/sub 2/O/sub 2/ in human erythrocytes. Recently, however, mammalian catalase was found to have tightly bound NADPH and to require NADPH for the prevention and reversal of inactivation by its toxic substrate (H/sub 2/O/sub 2/). Since both catalase and the glutathione pathway are dependent on NADPH for function, this finding raises the possibility that both mechanisms destroy H/sub 2/O/sub 2/ in human erythrocytes. A comparison of normal and acatalasemic erythrocytes in the present study indicated that catalase accounts for more than half of the destruction of H/sub 2/O/sub 2/ when H/sub 2/O/sub 2/ is generated at a rate comparable to that which leads to hemolysis in G6PD- deficient erythrocytes.

  17. Low dose X -ray effects on catalase activity in animal tissue

    NASA Astrophysics Data System (ADS)

    Focea, R.; Nadejde, C.; Creanga, D.; Luchian, T.

    2012-12-01

    This study was intended to investigate the effect of low-dose X ray-irradiation upon the activity of catalase (CAT) in freshly excised chicken tissues (liver, kidney, brain, muscle). The tissue samples were irradiated with 0.5Gy and 2Gy respectively, in a 6 MV photon beam produced by a clinical linear accelerator (VARIAN CLINAC 2100SC). The dose rate was of 260.88cGy/min. at 100 cm source to sample distance. The catalase level was assayed spectrophotometrically, based on reaction kinetics, using a catalase UV assay kit (SIGMA). Catalase increased activity in various tissue samples exposed to the studied X ray doses (for example with 24 % in the liver cells, p<0.05) suggested the stimulation of the antioxidant enzyme biosynthesis within several hours after exposure at doses of 0.5 Gy and 2 Gy; the putative enzyme inactivation could also occur (due to the injuries on the hydrogen bonds that ensure the specificity of CAT active site) but the resulted balance of the two concurrent processes indicates the cell ability of decomposing the hydrogen peroxide-with benefits for the cell physiology restoration for the chosen low dose radiation.

  18. Induction and inactivation of catalase and superoxide dismutase of Escherichia coli by ozone

    SciTech Connect

    Whiteside, C.; Hassan, H.M.

    1987-09-01

    Oxyradicals have been implicated in ozone (O/sub 3/) toxicity and in other oxidant stress. In this study, we investigated the effects of O/sub 3/ on the biosynthesis of the antioxidant enzymes catalase and superoxide dismutase in Escherichia coli to determine their role in the defense against ozone toxicity. Inhibition of growth and loss of viability were observed in cultures exposed to ozone. Results also showed an increase in the activities of catalase and superoxide dismutase in cultures exposed to ozone, which was shown to be due to true induction rather than activation of preexisting apoproteins. Cessation of O/sub 3/ exposure resulted in 30 min of continual high rate of catalase biosynthesis followed by a gradual decrease in the level of the enzyme approaching that of control cultures. This decrease was attributed to a concomitant cessation of de novo enzyme synthesis and dilution of preexisting enzyme by cellular growth. Ozonation of cell-free extracts showed that superoxide dismutase and catalase are subject to oxidative inactivation by ozone. In vivo induction of these enzymes may represent an adaptive response evolved to protect cells against ozone toxicity.

  19. Do Superoxide Dismutase (SOD) and Catalase (CAT) protect Cells from DNA Damage Induced by Active Arsenicals?

    EPA Science Inventory

    Superoxide dismutase (SOD) catalyzes the conversion of superoxide to hydrogen peroxide, which can be converted to water and oxygen through the action of catalase. Heterozygous mice of strain B6: 129S7-SodltmlLeb/J were obtained from Jackson Laboratories and bred to produce offspr...

  20. Regulation of the oxidative stress protective enzymes, catalase and superoxide dismutase in Xanthomonas — a review

    Microsoft Academic Search

    Suvit Loprasert; Paiboon Vattanaviboon; Wipa Praituan; Sangpen Chamnongpol; Skorn Mongkolsuk

    1996-01-01

    Xanthomonas showed atypical regulation of catalase (Kat) and superoxide dismutase with respect to growth phase and response to various inducers. The highest levels of both enzymes were detected during early log phase of growth and declined as growth continued. This was in contrast to resistance levels to superoxides, H2O2 and organic peroxides, which reached maximum levels during stationary phase. Xanthomonas

  1. Direct evidence for catalase activity of [Ru(V)(edta)(O)](-).

    PubMed

    Chatterjee, Debabrata; Jaiswal, Namita; Franke, Alicja; van Eldik, Rudi

    2014-12-01

    Reported is the first example of a ruthenium(III) complex, Ru(III)(edta) (edta(4-) = ethylenediaminetetraacetate), that catalyzes the disproportion of H2O2 to O2 and water in resemblance to catalase activity, and shedding light on the possible mechanism of action of the [Ru(V)(edta)(O)](-) formed in the reacting system. PMID:25307989

  2. Catalase and superoxide dismutase in alfalfa root nodules. [Medicago sativa L

    SciTech Connect

    Becana, M.; Aparicio-Tejo, P.M.; Sanchez-Diaz, M.

    1986-04-01

    Catalase and superoxide dismutase (SOD), in scavenging H/sub 2/ O/sub 2/ and O/sub 2/, respectively, have been recently proposed to play a role in leghemoglobin protection. The occurrence of catalase and SOD activities in alfalfa (Medicago sativa L.) nodule cytosol is reported here. Enzymes were extracted at 0-4/sup 0/C from 0.5 g fresh nodules with 12 ml of a medium containing K-phosphate buffer 50 mM, pH 7.8 and Na/sub 2/EDTA 0.1 mM. The homogenate was filtered and centrifuged at 18,000 xg for 10 min, and the resulting supernatant was used for catalase assay. A further precipitation of leghemoglobin was required to avoid interferences with SOD determination. Catalase was determined by back-titration with KMnO/sub 4/. SOD was assayed by measuring the inhibition of nitro blue tetrazolium reduction. The sensitivity of SOD activity to CN/sup -/ was tested by including 1 mM KCN in the reaction mixture. Catalase activity of alfalfa nodule cytosol was 237 +/- 1 units/mg protein, decreasing very significantly (P < 0.01, Duncan's multiple range test) at 20 mM NO/sub 3//sup -/. Typical specific SOD activities were 94 +/- 5 and 65 +/- 4 units/mg protein, without CN/sup -/ and with CN/sup -/, respectively. Both activities increased very significantly at 20 mM NO/sub 3//sup -/. SOD activities with CN/sup -/ were 70-80% those without CN/sup -/ within the range of NO/sub 3//sup -/ investigated (0-20 mM).

  3. Catalase and superoxide dismutase activities as biomarkers of oxidative stress in workers exposed to mercury vapors

    SciTech Connect

    Perrin-Nadif, R.; Dusch, M.; Mur, J.M.; Koch, C. [INRS, Vandoeuvre-les-Nancy (France)] [INRS, Vandoeuvre-les-Nancy (France); Schmitt, P. [Association InterEntreprises de Medecine du Travail du Bas-Rhin, Strasbourg (France)] [Association InterEntreprises de Medecine du Travail du Bas-Rhin, Strasbourg (France)

    1996-06-07

    We investigated the role of three blood antioxidant enzyme activities and total antioxidant status (TAS) as biological markers of oxidative stress in workers exposed to mercury (Hg{degrees}) vapors. Twenty-two female workers took part in the study. Blood and urine sampling for biological analyses was performed. The workers were classified into three subgroups according to their creatinine-corrected Hg concentration in urine. Blood antioxidant enzyme activities and TAS were compared between groups with nonparametric distribution-free methods. A significant difference existed in catalase activity and a slight, but not significant, difference existed in Cu{sup 2+}/Zn{sup 2+} superoxide dismutase (Cu{sup 2+}/Zn{sup 2+} SOD) activity between the three groups. No differences were observed in either the glutathione peroxidase activity or the TAS between these groups. Catalase and Cu{sup 2+}/Zn{sup 2+} SOD activities were increased in the groups of workers with higher creatinine-corrected urinary Hg concentrations when compared with the group of lower creatinine-corrected urinary Hg concentrations. Catalase activity was positively correlated with the creatinine-corrected concentration of Hg in urine, and Cu{sup 2+}/Zn{sup 2+} SOD activity was slightly correlated with the creatinine-corrected concentration of Hg in urine. The role of erythrocyte catalase and Cu{sup 2}/Zn{sup 2+} SOD activities we have measured is in agreement with the hypothesis of the involvement of reactive oxygen species production as an important event in chronic exposure to Hg{degrees} vapors in humans. In spite of the small sample size, results indicate that erythrocyte catalase and Cu{sup 2+}/Zn{sup 2+} SOD activities could be considered as markers of biological effect in workers exposed to Hg{degrees} vapors. 24 refs., 3 figs., 2 tabs.

  4. Understanding the role of the catalase/peroxide genes in H2O2 resistance of E. coli serotype O157:H7 biofilms

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Introduction: Escherichia coli serotype O157:H7 defenses against H2O2 include the peroxiredoxin AhpC and three catalases: KatG (catalase-peroxidase), KatE (catalase), and the plasmid-encoded KatP (catalase/peroxidase). AhpC, KatG, and KatP are induced by OxyR in exponential phase, while KatE is indu...

  5. Synergistic roles of Helicobacter pylori methionine sulfoxide reductase and GroEL in repairing oxidant-damaged catalase.

    PubMed

    Mahawar, Manish; Tran, ViLinh; Sharp, Joshua S; Maier, Robert J

    2011-05-27

    Hypochlorous acid (HOCl) produced via the enzyme myeloperoxidase is a major antibacterial oxidant produced by neutrophils, and Met residues are considered primary amino acid targets of HOCl damage via conversion to Met sulfoxide. Met sulfoxide can be repaired back to Met by methionine sulfoxide reductase (Msr). Catalase is an important antioxidant enzyme; we show it constitutes 4-5% of the total Helicobacter pylori protein levels. msr and katA strains were about 14- and 4-fold, respectively, more susceptible than the parent to killing by the neutrophil cell line HL-60 cells. Catalase activity of an msr strain was much more reduced by HOCl exposure than for the parental strain. Treatment of pure catalase with HOCl caused oxidation of specific MS-identified Met residues, as well as structural changes and activity loss depending on the oxidant dose. Treatment of catalase with HOCl at a level to limit structural perturbation (at a catalase/HOCl molar ratio of 1:60) resulted in oxidation of six identified Met residues. Msr repaired these residues in an in vitro reconstituted system, but no enzyme activity could be recovered. However, addition of GroEL to the Msr repair mixture significantly enhanced catalase activity recovery. Neutrophils produce large amounts of HOCl at inflammation sites, and bacterial catalase may be a prime target of the host inflammatory response; at high concentrations of HOCl (1:100), we observed loss of catalase secondary structure, oligomerization, and carbonylation. The same HOCl-sensitive Met residue oxidation targets in catalase were detected using chloramine-T as a milder oxidant. PMID:21460217

  6. Benzothiazole Aniline Tetra(ethylene glycol) and 3-Amino-1,2,4-triazole Inhibit Neuroprotection against Amyloid Peptides by Catalase Overexpression in Vitro

    PubMed Central

    2013-01-01

    Alzheimer’s disease, Familial British dementia, Familial Danish dementia, Type 2 diabetes mellitus, plus Creutzfeldt-Jakob disease are associated with amyloid fibril deposition and oxidative stress. The antioxidant enzyme catalase is a neuroprotective amyloid binding protein. Herein the effects of catalase overexpression in SH-SY5Y neuronal cells on the toxicity of amyloid-? (A?), amyloid-Bri (ABri), amyloid-Dan (ADan), amylin (IAPP), and prion protein (PrP) peptides were determined. Results showed catalase overexpression was neuroprotective against A?, ABri, ADan, IAPP, and PrP peptides. The catalase inhibitor 3-amino-1,2,4-triazole (3-AT) and catalase-amyloid interaction inhibitor benzothiazole aniline tetra(ethylene glycol) (BTA-EG4) significantly enhanced neurotoxicity of amyloid peptides in catalase overexpressing neuronal cells. This suggests catalase neuroprotection involves breakdown of hydrogen peroxide (H2O2) plus a direct binding interaction between catalase and the A?, ABri, ADan, IAPP, and PrP peptides. Kisspeptin 45–50 had additive neuroprotective actions against the A? peptide in catalase overexpressing cells. The effects of 3-AT had an intracellular site of action, while catalase-amyloid interactions had an extracellular component. These results suggest that the 3-AT and BTA-EG4 compounds may be able to inhibit endogenous catalase mediated neuroprotection. Use of BTA-EG4, or compounds that inhibit catalase binding to amyloid peptides, as potential therapeutics for Neurodegenerative diseases may therefore result in unwanted effects. PMID:23968537

  7. Binding of chrysoidine to catalase: spectroscopy, isothermal titration calorimetry and molecular docking studies.

    PubMed

    Yang, Bingjun; Hao, Fang; Li, Jiarong; Chen, Dongliang; Liu, Rutao

    2013-11-01

    Chrysoidine is an industrial azo dye and the presence of chrysoidine in water and food has become an environmental concern due to its negative effects on human beings. In this work, the interactions between chrysoidine and bovine liver catalase (BLC) were explored. Obvious loss in catalytic activity was observed after incubation of BLC with chrysoidine, and the inhibition effect of BLC was found to be of the non-competitive type. No profound conformational change of BLC occurs in the presence of chrysoidine as revealed by UV-vis absorption, circular dichroism and fluorescence spectroscopy studies. Isothermal titration calorimetry results indicate that catalase has two sets of binding sites for chrysoidine. Further, molecular docking simulations show that chrysoidine is located within the bottleneck in the main channel of the substrate to the active site of BLC, which explain the activity inhibition of BLC by chrysoidine. PMID:24001681

  8. Catalase-independent early-gene expression in rat brain following acute ethanol exposure

    Microsoft Academic Search

    Juan J. Canales

    2004-01-01

    Early-gene expression evoked by acute ethanol treatment was studied in rat brain by quantitative immunocytochemistry, with reference to ethanol metabolism by the enzyme catalase. Colocalization with mu-opioid receptor (MOR) sites was also examined. Ethanol challenges [1, 2.5, and 4 g\\/kg intraperitoneally (i.p.)] evoked dose-dependent increases in c-Fos expression in several brain regions, but overlap with MOR-rich sites was only partial.

  9. Adenovirus-mediated catalase gene transfer reduces oxidant stress in human, porcine and rat pancreatic islets

    Microsoft Academic Search

    P. Y. Benhamou; C. Moriscot; M. J. Richard; O. Beatrix; L. Badet; F. Pattou; J. Kerr-Conte; J. Chroboczek; P. Lemarchand; S. Halimi

    1998-01-01

    Summary   Susceptibility of pancreatic islets to oxidant stress may affect islet viability and contribute to primary non function of\\u000a allo- or xenogenic grafts. We investigated the influence of overexpression of catalase (CAT) on the viability of human, porcine\\u000a and rat islets, as well as INS-1 beta-cell line. Islets were transfected with a replication-deficient adenovirus vector containing\\u000a human CAT cDNA under

  10. Transgenic mitochondrial superoxide dismutase and mitochondrially targeted catalase prevent antiretroviral-induced oxidative stress and cardiomyopathy

    Microsoft Academic Search

    James J Kohler; Ioan Cucoranu; Earl Fields; Elgin Green; Stanley He; Amy Hoying; Rodney Russ; Allison Abuin; David Johnson; Seyed H Hosseini; C Michael Raper; William Lewis

    2009-01-01

    Transgenic mice (TG) were used to define mitochondrial oxidative stress and cardiomyopathy (CM) induced by zidovudine (AZT), an antiretroviral used to treat HIV\\/AIDS. Genetically engineered mice either depleted or overexpressed mitochondrial superoxide dismutase (SOD2+\\/? KOs and SOD2-OX, respectively) or expressed mitochondrially targeted catalase (mCAT). TGs and wild-type (WT) littermates were treated (oral AZT, 35 days). Cardiac mitochondrial H2O2, aconitase activity,

  11. Glucose oxidase and catalase activities of Penicillium variabile P16 immobilized in polyurethane sponge

    Microsoft Academic Search

    F Federici; M Petruccioli; P Piccioni

    1996-01-01

    Conidia ofPenicillium variabile P16 were immobilized in polyurethane sponge and used in repeated-batch processes in a fluidized-bed reactor. Optimal conditions for production of glucose oxidase and catalase were: inoculum size, 10%; glucose concentration, 80 g L-1; Ca-carbonate concentration, 15 g L-1; temperature, 28°C and aeration rate, 4 VV-1 min-1. In an extended repeated-batch process, glucose oxidase activity was highest after

  12. Malondialdehyde and catalase as the serum biomarkers of allyl chloride-induced toxic neuropathy

    Microsoft Academic Search

    Qing-Shan Wang; Cui-Li Zhang; Xiu-Lan Zhao; Su-Fang Yu; Ke-Qin Xie

    2006-01-01

    Chronic exposure to allyl chloride (AC) is known to produce a central-peripheral distal axonopathy. To access the biomarker of exposure and elucidate the mechanism of neuropathy induced by AC, we performed a longitudinal observational study of malondialdehyde (MDA), anti-reactive oxygen species (anti-ROS), glutathione (GSH), catalase (CAT), glutathione peroxidase (GPx) and superoxide dismutase (SOD) in rats serum and sciatic nerve after

  13. Role of Superoxide in Catalase-Peroxidase-Mediated Isoniazid Action against Mycobacteria

    Microsoft Academic Search

    JIAN-YING WANG; RICHARD M. BURGER; KARL DRLICA

    Isoniazid (INH) activation in vitro is associated with reduction of the mycobacterial ferric KatG catalase- peroxidase by hydrazine and reaction with O2 to form an oxyferrous enzyme complex. Since this complex could also form directly via reaction of ferric KatG with superoxide, intracellular activation might be responsive to superoxide concentration. When Mycobacterium smegmatis carrying the M. bovis katG gene was

  14. cDNA cloning and differential gene expression of three catalases in pumpkin

    Microsoft Academic Search

    Muneharu Esaka; Naoko Yamada; Masao Kitabayashi; Yuji Setoguchi; Ryuji Tsugeki; Maki Kondo; Mikio Nishimura

    1997-01-01

    Three cDNA clones (cat1, cat2, cat3) for catalase (EC 1.11.1.6) were isolated from a cDNA library of pumpkin (Cucurbita sp.) cotyledons. In northern blotting using the cDNA-specific probe, the cat1 mRNA levels were high in seeds and early seedlings of pumpkin. The expression pattern of cat1 was similar to that of malate synthase, a characteristic enzyme of glyoxysomes. These data

  15. Thermotolerant Campylobacter with no or weak catalase activity isolated from dogs

    Microsoft Academic Search

    Karin Sandstedt; Jan Ursing; Mats Walder

    1983-01-01

    ThermotolerantCampylobacter strains isolated from dog feces were characterized by phenotypical tests, DNA base composition, and DNA-DNA-hybridization. Out of 98 strains, 63 were catalase negative or weakly reacting (CNW); they were found in diarrheic as well as in healthy dogs. The CNW strains were all nalidixic-acid sensitive, hippurate negative, and grew at 42°C but not at 25°C. Seven strains were further

  16. Superoxide Dismutase, Peroxidatic Activity and Catalase in Mycobacterium leprae Purified from Armadillo Liver

    Microsoft Academic Search

    P. R. WHEELER; D. GREGORY

    1980-01-01

    ~~ Superoxide dismutase has been identified and peroxidatic activity demonstrated in Mycobacterium leprae. The superoxide dismutase, shown indirectly to be a manganese- containing enzyme, was present at low activity in the cell-free extract. Peroxidatic activity was detected in a haemoprotein on polyacrylamide gels, but quantitative assay was not possible. Catalase, although present in a cell-free extract, appeared to be a

  17. Extension of Life-Span with Superoxide Dismutase\\/Catalase Mimetics

    Microsoft Academic Search

    Simon Melov; Joanne Ravenscroft; Sarwatt Malik; Matt S. Gill; David W. Walker; Peter E. Clayton; Douglas C. Wallace; Bernard Malfroy; Susan R. Doctrow; Gordon J. Lithgow

    2000-01-01

    We tested the theory that reactive oxygen species cause aging. We augmented the natural antioxidant systems of Caenorhabditis elegans with small synthetic superoxide dismutase\\/catalase mimetics. Treatment of wild-type worms increased their mean life-span by a mean of 44 percent, and treatment of prematurely aging worms resulted in normalization of their life-span (a 67 percent increase). It appears that oxidative stress

  18. Complete Nucleotide Sequence of cDNA and Deduced Amino Acid Sequence of Rat Liver Catalase

    Microsoft Academic Search

    Shuichi Furuta; Hiroaki Hayashi; Makoto Hijikata; Shoko Miyazawa; Takashi Osumi; Takashi Hashimoto

    1986-01-01

    We have isolated five cDNA clones for rat liver catalase (hydrogen peroxide: hydrogen peroxide oxidoreductase, EC 1.11.1.6). These clones overlapped with each other and covered the entire length of the mRNA, which had been estimated to be 2.4 kilobases long by blot hybridization analysis of electrophoretically fractionated RNA. Nucleotide sequencing was carried out on these five clones and the composite

  19. Cytotoxicity of lawsone and cytoprotective activity of antioxidants in catalase mutant Escherichia coli.

    PubMed

    Sauriasari, Rani; Wang, Da-Hong; Takemura, Yoko; Tsutsui, Ken; Masuoka, Noriyoshi; Sano, Kuniaki; Horita, Masako; Wang, Bing-Ling; Ogino, Keiki

    2007-06-01

    Lawsone is an active naphthoquinone derivative isolated from henna (Lawsonia inermis L.), a widely used hair dye. Previous study on the toxicity of lawsone remains unclear since the involvement of oxidative stress and the kind of ROS (reactive oxygen species) involved have not been fully resolved yet. This present study reports the cytotoxic effects of lawsone and henna. We carried out CAT assay (a zone of inhibition test of bacterial growth and colony-forming efficiency test of transformant Escherichia coli strains that express mammalian catalase gene derived from normal catalase mice (Cs(a)) and catalase-deficient mutant mice (Cs(b))), Ames mutagenicity assay and H(2)O(2) generation assay. Lawsone generated H(2)O(2) slightly in phosphate buffer system and was not mutagenic in Ames assay using TA 98, TA 100 and TA 102, both in the absence and presence of metabolic activation. Lawsone exposure inhibited the growth of both Cs(a) and Cs(b) strains in a dose-dependent manner. Mean zone diameter for Cs(a) was 9.75+/-0.96 mm and 12.75+/-1.5 mm for Cs(b). Natural henna leaves did not show toxic effects, whereas two out of four samples of marketed henna products were shown toxicity effects. Catalase abolished zone of inhibition (ZOI) of marketed henna products, eliminated ZOI of lawsone in a dose-dependent manner and low concentration of exogenous MnSOD and Cu/ZnSOD eliminated the toxicity. Histidine and DTPA, the metal chelator; BHA and low concentration of capsaicin, the inducer of NADH-quinone reductase, effectively protected Cs(a) and Cs(b) against lawsone in this study. We suggest that lawsone cytotoxicity is probably mediated, at least in part, by the release of O(2)(-), H(2)O(2) and OH(-). PMID:17442476

  20. Catalase-like activity of horseradish peroxidase: relationship to enzyme inactivation by H2O2.

    PubMed Central

    Hernández-Ruiz, J; Arnao, M B; Hiner, A N; García-Cánovas, F; Acosta, M

    2001-01-01

    H2O2 is the usual oxidizing substrate of horseradish peroxidase C (HRP-C). In the absence in the reaction medium of a one-electron donor substrate, H2O2 is able to act as both oxidizing and reducing substrate. However, under these conditions the enzyme also undergoes a progressive loss of activity. There are several pathways that maintain the activity of the enzyme by recovering the ferric form, one of which is the decomposition of H2O2 to molecular oxygen in a similar way to the action of catalase. This production of oxygen has been kinetically characterized with a Clark-type electrode coupled to an oxygraph. HRP-C exhibits a weak catalase-like activity, the initial reaction rate of which is hyperbolically dependent on the H2O2 concentration, with values for K(2) (affinity of the first intermediate, compound I, for H2O2) and k(3) (apparent rate constant controlling catalase activity) of 4.0 +/- 0.6 mM and 1.78 +/- 0.12 s(-1) respectively. Oxygen production by HRP-C is favoured at pH values greater than approx. 6.5; under similar conditions HRP-C is also much less sensitive to inactivation during incubations with H2O2. We therefore suggest that this pathway is a major protective mechanism of HRP-C against such inactivation. PMID:11171085

  1. Optimization of permeabilization process of yeast cells for catalase activity using response surface methodology

    PubMed Central

    Trawczy?ska, Ilona; Wójcik, Marek

    2015-01-01

    Biotransformation processes accompanied by whole yeast cells as biocatalyst are a promising area of food industry. Among the chemical sanitizers currently used in food technology, hydrogen peroxide is a very effective microbicidal and bleaching agent. In this paper, permeabilization has been applied to Saccharomyces cerevisiae yeast cells aiming at increased intracellular catalase activity for decomposed H2O2. Ethanol, which is non-toxic, biodegradable and easily available, has been used as permeabilization factor. Response surface methodology (RSM) has been applied in determining the influence of different parameters on permeabilization process. The aim of the study was to find such values of the process parameters that would yield maximum activity of catalase during decomposition of hydrogen peroxide. The optimum operating conditions for permeabilization process obtained by RSM were as follows: 53% (v/v) of ethanol concentration, temperature of 14.8 °C and treatment time of 40 min. After permeabilization, the activity of catalase increased ca. 40 times and its maximum value equalled to 4711 U/g. PMID:26019618

  2. Role of phosphate on stability and catalase mimetic activity of cerium oxide nanoparticles.

    PubMed

    Singh, Ragini; Singh, Sanjay

    2015-08-01

    Cerium oxide nanoparticles (CeNPs) have been recently shown to scavenge reactive oxygen and nitrogen species (ROS and RNS) in different experimental model systems. CeNPs (3+) and CeNPs (4+) have been shown to exhibit superoxide dismutase (SOD) and catalase mimetic activity, respectively. Due to their nanoscale dimension, CeNPs are expected to interact with the components of biologically relevant buffers and medium, which could alter their catalytic properties. We have demonstrated earlier that CeNPs (3+) interact with phosphate and lose the SOD activity. However, very little is known about the interaction of CeNPs (4+) with the phosphate and other anions, predominantly present in biological buffers and their effects on the catalase mimetic-activity of these nanoparticles. In this study, we report that catalase mimetic-activity of CeNPs (4+) is resistant to the phosphate anions, pH changes and composition of cell culture media. Given the abundance of phosphate anions in the biological system, it is likely that internalized CeNPs would be influenced by cytoplasmic and nucleoplasmic concentration of phosphate. PMID:26011425

  3. Superoxide dismutase and catalase conjugated to polyethylene glycol increases endothelial enzyme activity and oxidant resistance

    SciTech Connect

    Beckman, J.S.; Minor, R.L. Jr.; White, C.W.; Repine, J.E.; Rosen, G.M.; Freeman, B.A.

    1988-05-15

    Covalent conjugation of superoxide dismutase and catalase with polyethylene glycol (PEG) increases the circulatory half-lives of these enzymes from <10 min to 40 h, reduced immunogenicity, and decreases sensitivity to proteolysis. Because PEG has surface active properties and can induce cell fusion, the authors hypothesized that PEG conjugation could enhance cell binding and association of normally membrane-impermeable enzymes. Incubation of cultured porcine aortic endothelial cells with /sup 125/I-PEG-catalase or /sup 125/I-PEG-superoxide dismutase produced a linear, concentration-dependent increase in cellular enzyme activity and radioactivity. Fluorescently labeled PEG-superoxide dismutase incubated with endothelial cells showed a vesicular localization. Mechanical injury to cell monolayers, which is known to stimulate endocytosis, further increased the uptake of fluorescent PEG-superoxide dismutase. Addition of PEG and PEG-conjugated enzymes perturbed the spin-label binding environment, indicative of producing an increase in plasma membrane fluidity. Thus, PEG conjugation to superoxide dismutase and catalase enhances cell association of these enzymes in a manner which increases cellular enzyme activities and provides prolonged protection from partially reduced oxygen species.

  4. On the role of catalase in the oxidation of tissue fatty acids

    SciTech Connect

    Crane, D.; Masters, C.

    1984-02-15

    The role of catalase in lipid metabolism has been studied by means of a comparison of the turnover characteristics of the major lipid classes in the normal mouse with those of animals in which the catalase activity had been inhibited and blocked by aminotriazole and allylisopropylacetamide. Double isotope ratios were determined in the lipid fractions of several tissues following the injection of labeled glycerol, and a number of significant differences were identified between these treatments. Since catalase is recognized as an integral component of the peroxisomal pathway of fatty acid oxidation, these results may be taken as indicating that interruption of the process of peroxisomal beta-oxidation in this manner cause extensive perturbations of lipid metabolism in the living animal, and these perturbations extend well beyond those tissues where the predominant localization of these organelles occurs. The concept which derives from these data--that of a significant regulatory role of peroxisomes in relation to the overall balance of lipid metabolism in the animal body--is described and discussed.

  5. Murine and human b locus pigmentation genes encode a glycoprotein (gp75) with catalase activity

    SciTech Connect

    Halaban, R.; Moellmann, G. (Yale Univ. School of Medicine, New Haven, CT (USA))

    1990-06-01

    Melanogenesis is regulated in large part by tyrosinase, and defective tyrosinase leads to albinism. The mechanisms for other pigmentation determinants (e.g., those operative in tyrosinase-positive albinism and in murine coat-color mutants) are not yet known. One murine pigmentation gene, the brown (b) locus, when mutated leads to a brown (b/b) or hypopigmentated (B{sup lt}/B{sup lt}) coat versus the wild-type black (B/B). The authors show that the b locus codes for a glycoprotein with the activity of a catalase (catalase B). Only the c locus protein is a tyrosinase. Because peroxides may be by-products of melanogenic activity and hydrogen peroxide in particular is known to destroy melanin precursors and melanin, they conclude that pigmentation is controlled not only by tyrosinase but also by a hydroperoxidase. The studies indicate that catalase B is identical with gp75, a known human melanosomal glycoprotein; that the b mutation is in a heme-associated domain; and that the B{sup lt} mutation renders the protein susceptible to rapid proteolytic degradation.

  6. katGI and katGII encode two different catalases-peroxidases in Mycobacterium fortuitum.

    PubMed Central

    Menéndez, M C; Ainsa, J A; Martín, C; García, M J

    1997-01-01

    It has been suggested that catalase-peroxidase plays an important role in several aspects of mycobacterial metabolism and is a virulence factor in the main pathogenic mycobacteria. In this investigation, we studied genes encoding for this protein in the fast-growing opportunistic pathogen Mycobacterium fortuitum. Nucleotide sequences of two different catalase-peroxidase genes (katGI and katGII) of M. fortuitum are described. They show only 64% homology at the nucleotide level and 55% identity at the amino acid level, and they are more similar to catalases-peroxidases from different bacteria, including mycobacteria, than to each other. Both proteins were found to be expressed in actively growing M. fortuitum, and both could also be expressed when transformed into Escherichia coli and M. aurum. We detected the presence of a copy of IS6100 in the neighboring region of a katG gene in the M. fortuitum strain in which this element was identified (strain FC1). The influence of each katG gene on isoniazid (isonicotinic acid hydrazide; INH) susceptibility of mycobacteria was checked by using the INH-sensitive M. aurum as the host. Resistance to INH was induced when katGI was transformed into INH-sensitive M. aurum, suggesting that this enzyme contributes to the natural resistance of M. fortuitum to the drug. This is the first report showing two different genes encoding same enzyme activity which are actively expressed within the same mycobacterial strain. PMID:9371430

  7. Murine and human b locus pigmentation genes encode a glycoprotein (gp75) with catalase activity.

    PubMed Central

    Halaban, R; Moellmann, G

    1990-01-01

    Melanogenesis is regulated in large part by tyrosinase (monophenol monooxygenase; monophenol, L-dopa:oxygen oxidoreductase, EC 1.14.18.1), and defective tyrosinase leads to albinism. The mechanisms for other pigmentation determinants (e.g., those operative in tyrosinase-positive albinism and in murine coat-color mutants) are not yet known. One murine pigmentation gene, the brown (b) locus, when mutated leads to a brown (b/b) or hypopigmented (Blt/Blt) coat versus the wild-type black (B/B). We show that the b locus codes for a glycoprotein with the activity of a catalase (hydrogen-peroxide:hydrogen-peroxide oxidoreductase, EC 1.11.1.6) (catalase B). Only the c locus protein is a tyrosinase. Because peroxides may be by-products of melanogenic activity and hydrogen peroxide in particular is known to destroy melanin precursors and melanin, we conclude that pigmentation is controlled not only by tyrosinase but also by a hydroperoxidase. Our studies indicate that catalase B is identical with gp75, a known human melanosomal glycoprotein; that the b mutation is in a heme-associated domain; and that the Blt mutation renders the protein susceptible to rapid proteolytic degradation. Images PMID:1693779

  8. Specific Function of the Met-Tyr-Trp Adduct Radical and Residues Arg-418 and Asp-137 in the Atypical Catalase Reaction of Catalase-Peroxidase KatG*

    PubMed Central

    Zhao, Xiangbo; Khajo, Abdelahad; Jarrett, Sanchez; Suarez, Javier; Levitsky, Yan; Burger, Richard M.; Jarzecki, Andrzej A.; Magliozzo, Richard S.

    2012-01-01

    Catalase activity of the dual-function heme enzyme catalase-peroxidase (KatG) depends on several structural elements, including a unique adduct formed from covalently linked side chains of three conserved amino acids (Met-255, Tyr-229, and Trp-107, Mycobacterium tuberculosis KatG numbering) (MYW). Mutagenesis, electron paramagnetic resonance, and optical stopped-flow experiments, along with calculations using density functional theory (DFT) methods revealed the basis of the requirement for a radical on the MYW-adduct, for oxyferrous heme, and for conserved residues Arg-418 and Asp-137 in the rapid catalase reaction. The participation of an oxyferrous heme intermediate (dioxyheme) throughout the pH range of catalase activity is suggested from our finding that carbon monoxide inhibits the activity at both acidic and alkaline pH. In the presence of H2O2, the MYW-adduct radical is formed normally in KatG[D137S] but this mutant is defective in forming dioxyheme and lacks catalase activity. KatG[R418L] is also catalase deficient but exhibits normal formation of the adduct radical and dioxyheme. Both mutants exhibit a coincidence between MYW-adduct radical persistence and H2O2 consumption as a function of time, and enhanced subunit oligomerization during turnover, suggesting that the two mutations disrupting catalase turnover allow increased migration of the MYW-adduct radical to protein surface residues. DFT calculations showed that an interaction between the side chain of residue Arg-418 and Tyr-229 in the MYW-adduct radical favors reaction of the radical with the adjacent dioxyheme intermediate present throughout turnover in WT KatG. Release of molecular oxygen and regeneration of resting enzyme are thereby catalyzed in the last step of a proposed catalase reaction. PMID:22918833

  9. Expression and activity of glutathione S-transferases and catalase in the shrimp Litopenaeus vannamei inoculated with a toxic Microcystis aeruginosa strain.

    PubMed

    Gonçalves-Soares, Daniela; Zanette, Juliano; Yunes, João S; Yepiz-Plascencia, Gloria M; Bainy, Afonso C D

    2012-04-01

    Microcystin (MC) produced during cyanobacteria blooms is notably toxic to human and wildlife. Conjugation with reduced glutathione (GSH) by glutathione S-transferase (GST) and the antioxidant enzymes defenses (e.g. catalase, CAT) are important biochemical defense mechanisms against MCs toxicity. We investigated the enzymatic activity of CAT and GST and the gene expression levels of CAT and eight GST isoforms in the hepatopancreas of the globally farmed shrimp Litopenaeus vannamei 48-h after injection with a sub-lethal dose of 100 ?g kg?¹ of a toxic Microcystis aeruginosa extract. MCs caused up-regulation for GST?, ? and a MAPEG isoform, by 12-, 2.8- and 1.8-fold, respectively, and increases in the total GST enzyme activity and CAT enzyme activity. The study points to the importance of further characterization for the L. vannamei GST isoforms and GST/CAT post-translational regulation processes to better understand the key mechanisms involved in the shrimp's defense against MC exposure. PMID:21889198

  10. Catalase in fluvial biofilms: a comparison between different extraction methods and example of application in a metal-polluted river.

    PubMed

    Bonnineau, Chloé; Bonet, Berta; Corcoll, Natàlia; Guasch, Helena

    2011-01-01

    Antioxidant enzymes are involved in important processes of cell detoxification during oxidative stress and have, therefore, been used as biomarkers in algae. Nevertheless, their limited use in fluvial biofilms may be due to the complexity of such communities. Here, a comparison between different extraction methods was performed to obtain a reliable method for catalase extraction from fluvial biofilms. Homogenization followed by glass bead disruption appeared to be the best compromise for catalase extraction. This method was then applied to a field study in a metal-polluted stream (Riou Mort, France). The most polluted sites were characterized by a catalase activity 4-6 times lower than in the low-polluted site. Results of the comparison process and its application are promising for the use of catalase activity as an early warning biomarker of toxicity using biofilms in the laboratory and in the field. PMID:21080224

  11. Amelioration of antigen-induced arthritis in rats by transfer of extracellular superoxide dismutase and catalase genes

    Microsoft Academic Search

    L Dai; A Claxson; S L Marklund; R Feakins; N Yousaf; Y Chernajovsky; P G Winyard

    2003-01-01

    Reactive oxygen species (ROS) have been implicated in the pathogenesis of rheumatoid arthritis (RA), while antioxidant enzymes, such as extracellular superoxide dismutase (EC-SOD) and catalase, block radical-induced events. The present study tested if the ex vivo transfer of EC-SOD and catalase genes alone or in combination in the knee joint of rats with monoarticular antigen-induced arthritis (AIA) was anti-inflammatory, and

  12. Purification, cloning, expression, and biochemical characterization of a monofunctional catalase, KatP, from Pigmentiphaga sp. DL-8.

    PubMed

    Dong, Weiliang; Hou, Ying; Li, Shuhuan; Wang, Fei; Zhou, Jie; Li, Zhoukun; Wang, Yicheng; Huang, Fei; Fu, Lei; Huang, Yan; Cui, Zhongli

    2015-04-01

    Catalases are essential components of the cellular equipment used to cope with oxidative stress. The monofunctional catalase KatP was purified from Pigmentiphaga sp. using ammonium sulfate precipitation (ASP), diethylaminoethyl ion exchange chromatography (IEC), and hydrophobic interaction chromatography (HIC). The purified catalase formed polymer with an estimated monomer molecular mass of 54kDa, which were resolved by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) and zymogram analysis. KatP exhibited a specific catalytic activity of 73,000U/mg, which was higher than that of catalase-1 of Comamonas terrigena N3H (55,900U/mg). Seven short tryptic fragments of this catalase were obtained by electrospray ionization quadrupole time-of-flight mass spectrometry (ESI-Q-TOF MS/MS), and the gene, katP, was cloned by PCR amplification and overexpressed in Escherichia coli BL21 (DE3). Based on the complete amino acid sequence, KatP was identified as a clade 3 monofunctional catalase. The specific activities of recombinant KatP for hydrogen peroxide (690,000U/mg) increased 9-fold over that of the parent strain. The Km and Vmax of recombinant KatP were 9.48mM and 81.2mol/minmg, respectively. The optimal pH and temperature for KatP were 7.0 and 37°C, respectively, and the enzyme displayed abroad pH-stable range of 4.0-11.0. The enzyme was inhibited by Zn(2+), Cu(2+), Cr(2+), and Mn(2+), whereas Fe(3+) and Mg(2+) stimulated KatP enzymatic activity. Interestingly, the catalase activity of recombinant KatP displayed high stability under different temperature and pH conditions, suggesting that KatP is a potential candidate for the production of catalase. PMID:25665507

  13. Catalase and superoxide dismutase-2 enhance survival and protect ovaries during overwintering diapause in the mosquito Culex pipiens

    PubMed Central

    Sim, Cheolho; Denlinger, David L.

    2011-01-01

    Lifespan extension and stress resistance are two important features of diapause that are essential for successful overwintering. We present several lines of evidence suggesting that genes encoding two antioxidant enzymes, catalase and superoxide dismutase-2, are critical in generating these characteristics during diapause in overwintering adults of the mosquito Culex pipiens. Expression of both catalase and sod-2 was dramatically higher in young diapausing females than in their nondiapausing counterparts at the same age. Suppression of catalase, but not sod-2, resulted in increased damage to the ovaries, as evidenced by signs of apoptosis in ovarian follicle cells. Adult survival time was shortened when levels of either catalase or sod-2 were suppressed using RNAi. Together these results imply that these two antioxidants are particularly important in promoting survival in diapausing females, while elevation of catalase also contributes to protection of the ovaries. In addition, RNAi directed against forkhead transcription factor (foxo), a gene thought to be upstream of the genes encoding these antioxidants, resulted in suppression of both catalase and sod-2. The linkage with FOXO suggests that the genes encoding these two antioxidants are components of an important gene network regulated by this transcription factor. PMID:21277308

  14. Utrophin upregulation in Duchenne muscular dystrophy.

    PubMed

    Hirst, R C; McCullagh, K J A; Davies, K E

    2005-12-01

    Duchenne Muscular Dystrophy (DMD) is a devastating, progressive muscle wasting disease for which there is currently no effective treatment. DMD is caused by mutations in the dystrophin gene many of which result in the absence of the large cytoskeletal protein dystrophin at the sarcolemma. Over-expression of utrophin, the autosomal paralogue of dystrophin, as a transgene in the mdx mouse (the mouse model of DMD) has demonstrated that utrophin can prevent the muscle pathology. Thus, up-regulation of utrophin in DMD muscle is a potential therapy for DMD. In this review we discuss recent advances in our understanding of the regulatory pathways controlling utrophin expression and the various approaches that have been applied to increasing the level of utrophin in the mdx mouse. These results are very encouraging and suggest that pharmacological up-regulation of utrophin may well be a feasible approach to therapy for DMD. PMID:16629055

  15. Iron deficiency upregulates Egr1 expression.

    PubMed

    Lee, Seung-Min; Lee, Sun Bok; Prywes, Ron; Vulpe, Christopher D

    2015-07-01

    Iron-deficient anemia is a prevalent disease among humans. We searched for genes regulated by iron deficiency and its regulated mechanism. cDNA microarrays were performed using Hepa1c1c7 cells treated with 100 ?M desferrioxamine (DFO), an iron chelator. Early growth response 1 (Egr1) was upregulated with at least 20-fold increase within 4 h and lasted for 24 h, which was confirmed by qRT-PCR. This activation was not seen by ferric ammonium citrate (FAC). DFO increased the transcriptional activity of Egr1-luc (-604 to +160) and serum response element (SRE)-luc reporters by 2.7-folds. In addition, cycloheximide lowered DFO-induced Egr1 mRNA levels. The upregulation of Egr1 by DFO was accompanied by sustained ERK signals along with phosphorylation of Elk-1. The ERK inhibitor (PD98059) prevented the DFO-induced Egr1 mRNAs. Overexpression of Elk-1 mutant (pElk-1S383A) decreased Egr1 reporter activity. DFO lowered reactive oxygen species (ROS) production and increased caspase 3/7 activity and cell death. DFO-induced iron deficiency upregulates Egr1 in part through transcriptional activation via ERK and Elk-1 signals, which may be important in the regulation of cell death in hepatoma cells. Our study demonstrated that iron depletion controlled the expression of Egr1, which might contribute to decisions about cellular fate in response to iron deficiency. PMID:25981695

  16. Respiration triggers heme transfer from cytochrome c peroxidase to catalase in yeast mitochondria.

    PubMed

    Kathiresan, Meena; Martins, Dorival; English, Ann M

    2014-12-01

    In exponentially growing yeast, the heme enzyme, cytochrome c peroxidase (Ccp1) is targeted to the mitochondrial intermembrane space. When the fermentable source (glucose) is depleted, cells switch to respiration and mitochondrial H2O2 levels rise. It has long been assumed that CCP activity detoxifies mitochondrial H2O2 because of the efficiency of this activity in vitro. However, we find that a large pool of Ccp1 exits the mitochondria of respiring cells. We detect no extramitochondrial CCP activity because Ccp1 crosses the outer mitochondrial membrane as the heme-free protein. In parallel with apoCcp1 export, cells exhibit increased activity of catalase A (Cta1), the mitochondrial and peroxisomal catalase isoform in yeast. This identifies Cta1 as a likely recipient of Ccp1 heme, which is supported by low Cta1 activity in ccp1? cells and the accumulation of holoCcp1 in cta1? mitochondria. We hypothesized that Ccp1's heme is labilized by hyperoxidation of the protein during the burst in H2O2 production as cells begin to respire. To test this hypothesis, recombinant Ccp1 was hyperoxidized with excess H2O2 in vitro, which accelerated heme transfer to apomyoglobin added as a surrogate heme acceptor. Furthermore, the proximal heme Fe ligand, His175, was found to be ? 85% oxidized to oxo-histidine in extramitochondrial Ccp1 isolated from 7-d cells, indicating that heme labilization results from oxidation of this ligand. We conclude that Ccp1 responds to respiration-derived H2O2 via a previously unidentified mechanism involving H2O2-activated heme transfer to apoCta1. Subsequently, the catalase activity of Cta1, not CCP activity, contributes to mitochondrial H2O2 detoxification. PMID:25422453

  17. Peroxisomes in Saccharomyces cerevisiae: immunofluorescence analysis and import of catalase A into isolated peroxisomes.

    PubMed Central

    Thieringer, R; Shio, H; Han, Y S; Cohen, G; Lazarow, P B

    1991-01-01

    To isolate peroxisomes from Saccharomyces cerevisiae of a quality sufficient for in vitro import studies, we optimized the conditions for cell growth and for cell fractionation. Stability of the isolated peroxisomes was monitored by catalase latency and sedimentability of marker enzymes. It was improved by (i) using cells that were shifted to oleic acid medium after growth to stationary phase in glucose precultures, (ii) shifting the pH from 7.2 to 6.0 during cell fractionation, and (iii) carrying out equilibrium density centrifugation with Nycodenz containing 0.25 M sucrose throughout the gradient. A concentrated peroxisomal fraction was used for in vitro import of catalase A. After 2 h of incubation, 62% of the catalase was associated with, and 16% was imported into, the organelle in a protease-resistant fashion. We introduced immunofluorescence microscopy for S. cerevisiae peroxisomes, using antibodies against thiolase, which allowed us to identify even the extremely small organelles in glucose-grown cells. Peroxisomes from media containing oleic acid were larger in size, were greater in number, and had a more intense fluorescence signal. The peroxisomes were located, sometimes in clusters, in the cell periphery, often immediately adjacent to the plasma membrane. Systematic immunofluorescence observations of glucose-grown S. cerevisiae demonstrated that all such cells contained at least one and usually several very small peroxisomes despite the glucose repression. This finding fits a central prediction of our model of peroxisome biogenesis: peroxisomes form by division of preexisting peroxisomes; therefore, every cell must have at least one peroxisome if additional organelles are to be induced in that cell. Images PMID:1986244

  18. Inhibition of catalase-dependent ethanol metabolism in alcohol dehydrogenase-deficient deermice by fructose.

    PubMed Central

    Handler, J A; Bradford, B U; Glassman, E B; Forman, D T; Thurman, R G

    1987-01-01

    Hepatic microsomal fractions from ADH (alcohol dehydrogenase)-negative deermice incubated with an NADPH-generating system metabolized butanol and ethanol at rates around 10 nmol/min per mg. In contrast, cytosolic catalase from ADH-negative deermouse liver oxidized ethanol, but not butanol, when incubated with an H2O2-generating system. Thus butanol is oxidized by cytochrome P-450 in microsomal fractions, but not by cytosolic catalase, in tissues from ADH-negative deermice. In perfused livers from ADH-negative deermice, rates of ethanol uptake at low concentrations of ethanol (1.5 mM) were about 60 mumol/h per g, yet butanol (1.5 mM) uptake was undetectable (less than 4 mumol/h per g). At higher concentrations of alcohol (25-30 mM), rates of ethanol uptake were about 80 mumol/h per g, whereas rates of butanol uptake were only about 9 mumol/h per g. Because rates of butanol metabolism via cytochrome P-450 in deermice were more than an order of magnitude lower than rates of ethanol uptake in livers from ADH-negative deermice, it is concluded that ethanol uptake by perfused livers from ADH-negative deermice is catalysed predominantly via catalase-H2O2. In support of this conclusion, rates of H2O2 generation, which are rate-limiting for the peroxidation of ethanol by catalase, were about 65 mumol/h per g in livers from ADH-negative deermice, values similar to rates of ethanol uptake of about 60 mumol/h per g measured under identical conditions. Rates of ethanol uptake by perfused livers from ADH-positive, but not from ADH-negative, deermice were increased by about 50% by infusion of fructose. Thus it is concluded that the stimulation of hepatic ethanol uptake by fructose is dependent on the presence of ADH. Unexpectedly, fructose decreased rates of ethanol metabolism and H2O2 generation by about 60% in perfused livers from ADH-negative deermice, probably by decreasing activation of fatty acids and thus diminishing rates of peroxisomal beta-oxidation. PMID:3435455

  19. Study of catalase immobilized on a silicate matrix for non-aqueous biocatalysis

    Microsoft Academic Search

    Elena Horozova; Nina Dimcheva

    2005-01-01

    Catalytic activity of catalase (CAT) immobilized on a modified silicate matrix to mediate decomposition of meta-chloroperoxibenzoic\\u000a acid (3-CPBA) in acetonitrile has been investigated by means of quantitative UV-spectrophotometry. Under the selected experimental\\u000a conditions, the kinetic parameters: the apparent Michaelis constat (K\\u000a M\\u000a ), the apparent maximum rate of enzymatic reaction (V\\u000a max\\u000a app\\u000a ), the first order specific rate constants

  20. Dynamics of the reaction glucose-catalase-glucose oxidase-hydrogen peroxide

    NASA Astrophysics Data System (ADS)

    ?íp, M.; Schreiberová, L.; Schreiber, I.

    2011-12-01

    Glucose-catalase-glucose oxidase-hydrogen peroxide reaction is one of the few known enzymatic systems studied in vitro in the field of nonlinear chemical dynamics. This reaction belongs to the family of oscillatory enzymatic reactions, which form a natural basis of oscillations in biological systems. A parametric study of dependence on mixing, temperature and initial concentrations of components in a batch stirred reactor was carried out. A newly proposed mathematical model of the reaction conforms to the obtained experimental data. Results of our experiments and simulations hint at further directions of research of non-linear dynamics in this reaction.

  1. Activity of Superoxide Dismutase and Catalase in Fenugreek (Trigonella foenum-graecum) in Response to Carbendazim.

    PubMed

    Sangeetha, R

    2010-01-01

    Fenugreek (Trigonella foenum-graecum) is an annual herb, used as a spice and traditionally as medicine. Fenugreek finds its uses in treating hyperglycemia, hyperlipidemia and disorders of gastro-intestinal and cardiovascular systems. Fenugreek cultivation in India is affected by fungal diseases like root-rot and damping-off and fungicides like carbendazim are used to overcome these infections. Fungicides play both positive and negative role in plants; fungicides protect plants from diseases and also exert oxidative stress simultaneously. This report is on the response of antioxidants, superoxide dismutase and catalase in fenugreek seeds and plants treated to different concentrations of carbendazim. PMID:20582202

  2. Antioxidant catalase rescues against high fat diet-induced cardiac dysfunction via an IKK?-AMPK-dependent regulation of autophagy.

    PubMed

    Liang, Lei; Shou, Xi-Ling; Zhao, Hai-Kang; Ren, Gu-Qun; Wang, Jian-Bang; Wang, Xi-Hui; Ai, Wen-Ting; Maris, Jackie R; Hueckstaedt, Lindsay K; Ma, Ai-Qun; Zhang, Yingmei

    2015-02-01

    Autophagy, a conservative degradation process for long-lived and damaged proteins, participates in a variety of biological processes including obesity. However, the precise mechanism of action behind obesity-induced changes in autophagy still remains elusive. This study was designed to examine the role of the antioxidant catalase in high fat diet-induced changes in cardiac geometry and function as well as the underlying mechanism of action involved with a focus on autophagy. Wild-type (WT) and transgenic mice with cardiac overexpression of catalase were fed low or high fat diet for 20 weeks prior to assessment of myocardial geometry and function. High fat diet intake triggered obesity, hyperinsulinemia, and hypertriglyceridemia, the effects of which were unaffected by catalase transgene. Myocardial geometry and function were compromised with fat diet intake as manifested by cardiac hypertrophy, enlarged left ventricular end systolic and diastolic diameters, fractional shortening, cardiomyocyte contractile capacity and intracellular Ca²? mishandling, the effects of which were ameliorated by catalase. High fat diet intake promoted reactive oxygen species production and suppressed autophagy in the heart, the effects of which were attenuated by catalase. High fat diet intake dampened phosphorylation of inhibitor kappa B kinase ?(IKK?), AMP-activated protein kinase (AMPK) and tuberous sclerosis 2 (TSC2) while promoting phosphorylation of mTOR, the effects of which were ablated by catalase. In vitro study revealed that palmitic acid compromised cardiomyocyte autophagy and contractile function in a manner reminiscent of fat diet intake, the effect of which was significantly alleviated by inhibition of IKK?, activation of AMPK and induction of autophagy. Taken together, our data revealed that the antioxidant catalase counteracts against high fat diet-induced cardiac geometric and functional anomalies possibly via an IKK?-AMPK-dependent restoration of myocardial autophagy. This article is part of a Special Issue entitled: Autophagy and protein quality control in cardiometabolic diseases. PMID:24993069

  3. Light Dependence of Catalase Synthesis and Degradation in Leaves and the Influence of Interfering Stress Conditions 1

    PubMed Central

    Hertwig, Birgit; Streb, Peter; Feierabend, Jürgen

    1992-01-01

    The enzyme catalase (EC 1.11.1.6) is light sensitive and subject to a rapid turnover in light, similar to the D1 reaction center protein of photosystem II. After 3 h of preadaptation to darkness or to different light intensities (90 and 520 ?mol m?2 s?1 photosynthetic photon flux density), sections of rye leaves (Secale cereale L.) were labeled for 4 h with l-[35S]methionine. From leaf extracts, catalase was immunoprecipitated with an antiserum prepared against the purified enzyme from rye leaves. Both incorporation into catalase and degradation of the enzyme polypeptide during a subsequent 16-h chase period increased with light intensity. At a photon flux density of 520 ?mol m?2 s?1, the apparent half-time of catalase in rye leaves was 3 to 4 h, whereas that of the D1 protein was much shorter, about 1.5 h. Exposure to stress conditions, such as 0.6 m NaCl or a heat-shock temperature of 40°C, greatly suppressed both total protein synthesis and incorporation of the label into catalase and into the D1 protein. Immunoblotting assays indicated that in light, but not in darkness, steady-state levels of catalase and of the D1 protein strongly declined during treatments with salt, heat shock, or translation inhibitors that block repair synthesis. Because of the common property of rapid photodegradation and the resulting dependence on continuous repair, declines in catalase as well as of the D1 protein represent specific and sensitive indicators for stress conditions that suppress the translational activities of leaves. Images Figure 1 Figure 2 Figure 4 Figure 5 Figure 7 Figure 8 PMID:16653156

  4. Cardiac-specific catalase overexpression rescues anthrax lethal toxin-induced cardiac contractile dysfunction: role of oxidative stress and autophagy

    PubMed Central

    2012-01-01

    Background Lethal and edema toxins secreted by Bacillus anthracis during anthrax infection were found to incite serious cardiovascular complications. However, the underlying mechanisms in anthrax lethal toxin-induced cardiac anomalies remain unknown. This study was designed to evaluate the impact of antioxidant enzyme catalase in anthrax lethal toxin-induced cardiomyocyte contractile dysfunction. Methods Wild type (WT) and cardiac-specific catalase overexpression mice were challenged with lethal toxin (2 ?g/g, intraperotineally (i.p.)). Cardiomyocyte contractile and intracellular Ca2+ properties were assessed 18 h later using an IonOptix edge-detection system. Proteasome function was assessed using chymotrypsin-like and caspase-like activities. GFP-LC3 puncta and Western blot analysis were used to evaluate autophagy and protein ubiquitination. Results Lethal toxin exposure suppressed cardiomyocyte contractile function (suppressed peak shortening, maximal velocity of shortening/re-lengthening, prolonged duration of shortening/re-lengthening, and impaired intracellular Ca2+ handling), the effects of which were alleviated by catalase. In addition, lethal toxin triggered autophagy, mitochondrial and ubiquitin-proteasome defects, the effects of which were mitigated by catalase. Pretreatment of cardiomyocytes from catalase mice with the autophagy inducer rapamycin significantly attenuated or ablated catalase-offered protection against lethal toxin-induced cardiomyocyte dysfunction. On the other hand, the autophagy inhibitor 3-MA ablated or significantly attenuated lethal toxin-induced cardiomyocyte contractile anomalies. Conclusions Our results suggest that catalase is protective against anthrax lethal toxin-induced cardiomyocyte contractile and intracellular Ca2+ anomalies, possibly through regulation of autophagy and mitochondrial function. PMID:23134810

  5. Catalase Overexpression Reduces Lactic Acid-Induced Oxidative Stress in Saccharomyces cerevisiae?

    PubMed Central

    Abbott, Derek A.; Suir, Erwin; Duong, Giang-Huong; de Hulster, Erik; Pronk, Jack T.; van Maris, Antonius J. A.

    2009-01-01

    Industrial production of lactic acid with the current pyruvate decarboxylase-negative Saccharomyces cerevisiae strains requires aeration to allow for respiratory generation of ATP to facilitate growth and, even under nongrowing conditions, cellular maintenance. In the current study, we observed an inhibition of aerobic growth in the presence of lactic acid. Unexpectedly, the cyb2? reference strain, used to avoid aerobic consumption of lactic acid, had a specific growth rate of 0.25 h?1 in anaerobic batch cultures containing lactic acid but only 0.16 h?1 in identical aerobic cultures. Measurements of aerobic cultures of S. cerevisiae showed that the addition of lactic acid to the growth medium resulted in elevated levels of reactive oxygen species (ROS). To reduce the accumulation of lactic acid-induced ROS, cytosolic catalase (CTT1) was overexpressed by replacing the native promoter with the strong constitutive TPI1 promoter. Increased activity of catalase was confirmed and later correlated with decreased levels of ROS and increased specific growth rates in the presence of high lactic acid concentrations. The increased fitness of this genetically modified strain demonstrates the successful attenuation of additional stress that is derived from aerobic metabolism and may provide the basis for enhanced (micro)aerobic production of organic acids in S. cerevisiae. PMID:19251894

  6. A bifunctional enzyme from Rhodococcus erythropolis exhibiting secondary alcohol dehydrogenase-catalase activities.

    PubMed

    Martinez-Rojas, Enriqueta; Kurt, Tutku; Schmidt, Udo; Meyer, Vera; Garbe, Leif-Alexander

    2014-11-01

    Alcohol dehydrogenases have long been recognized as potential biocatalyst for production of chiral fine and bulk chemicals. They are relevant for industry in enantiospecific production of chiral compounds. In this study, we identified and purified a nicotinamide adenine dinucleotide (NAD)-dependent secondary alcohol dehydrogenase (SdcA) from Rhodococcus erythropolis oxidizing ?-lactols into ?-lactones. SdcA showed broad substrate specificity on ?-lactols; secondary aliphatic alcohols with 8 and 10 carbon atoms were also substrates and oxidized with (2S)-stereospecificity. The enzyme exhibited moderate stability with a half-life of 5 h at 40 °C and 20 days at 4 °C. Mass spectrometric identification revealed high sequence coverage of SdcA amino acid sequence to a highly conserved catalase from R. erythropolis. The corresponding encoding gene was isolated from genomic DNA and subsequently overexpressed in Escherichia coli BL21 DE3 cells. In addition, the recombinant SdcA was purified and characterized in order to confirm that the secondary alcohol dehydrogenase and catalase activity correspond to the same enzyme. PMID:24846734

  7. Catalase-like activity studies of the manganese(II) adsorbed zeolites

    NASA Astrophysics Data System (ADS)

    ?içek, Ekrem; Dede, Bülent

    2013-12-01

    Preparation of manganese(II) adsorbed on zeolite 3A, 4A, 5A. AW-300, ammonium Y zeolite, organophilic, molecular sieve and catalase-like enzyme activity of manganese(II) adsorbed zeolites are reported herein. Firstly zeolites are activated at 873 K for two hours before contact manganese(II) ions. In order to observe amount of adsorption, filtration process applied for the solution. The pure zeolites and manganese(II) adsorbed zeolites were analysed by FT-IR. As a result according to the FT-IR spectra, the incorporation of manganese(II) cation into the zeolite structure causes changes in the spectra. These changes are expected particularly in the pseudolattice bands connected with the presence of alumino and silicooxygen tetrahedral rings in the zeolite structure. Furthermore, the catalytic activities of the Mn(II) adsorbed zeolites for the disproportionation of hydrogen peroxide were investigated in the presence of imidazole. The Mn(II) adsorbed zeolites display efficiency in the disproportion reactions of hydrogen peroxide, producing water and dioxygen in catalase-like activity.

  8. Cell-mediated Transfer of Catalase Nanoparticles from Macrophages to Brain Endothelial and Neural Cells

    PubMed Central

    Haney, Matthew J.; Zhao, Yuling; Li, Shu; Higginbotham, Sheila M.; Booth, Stephanie L.; Han, Huai-Yun; Vetro, Joseph A.; Mosley, R. Lee; Kabanov, Alexander V.; Gendelman, Howard E.; Batrakova, Elena V.

    2011-01-01

    Background Our laboratories forged the concept of macrophage delivery of protein antioxidants to attenuate neuroinflammation and nigrostriatal degeneration in Parkinson’s disease (PD). Notably, the delivery of the redox enzyme, catalase, incorporated into a polyion complex micelle (“nanozyme”) by bone marrow-derived macrophages protected the nigrostriatal against 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) intoxication. Nonetheless, how macrophage delivery of nanozyme increases the efficacy of catalase remains unknown. Methods Herein, we examined the transfer of nanozyme from macrophages to brain microvessel endothelial cells, neurons and astrocytes. Results Facilitated transport of the nanozyme from macrophages to endothelial and neural target cells occurred through endocytosis-independent mechanisms that involved fusion of cellular membranes; macrophage bridging conduits; and nanozyme lipid coatings. Nanozyme transfer was operative across an artificial blood brain barrier and showed efficient reactive oxygen species decomposition. Conclusion This is the first demonstration that drug-loaded macrophages discharge particles to contiguous target cells for potential therapeutic brain enzyme delivery. The pathways for drug delivery shown may be used for the treatment of degenerative disorders of the nervous system. PMID:21449849

  9. Double antisense plants lacking ascorbate peroxidase and catalase are less sensitive to oxidative stress than single antisense plants lacking ascorbate peroxidase or catalase.

    PubMed

    Rizhsky, Ludmila; Hallak-Herr, Elza; Van Breusegem, Frank; Rachmilevitch, Shimon; Barr, Jason E; Rodermel, Steven; Inzé, Dirk; Mittler, Ron

    2002-11-01

    The plant genome is a highly redundant and dynamic genome. Here, we show that double antisense plants lacking the two major hydrogen peroxide-detoxifying enzymes, ascorbate peroxidase (APX) and catalase (CAT), activate an alternative/redundant defense mechanism that compensates for the lack of APX and CAT. A similar mechanism was not activated in single antisense plants that lacked APX or CAT, paradoxically rendering these plants more sensitive to oxidative stress compared to double antisense plants. The reduced susceptibility of double antisense plants to oxidative stress correlated with suppressed photosynthetic activity, the induction of metabolic genes belonging to the pentose phosphate pathway, the induction of monodehydroascorbate reductase, and the induction of IMMUTANS, a chloroplastic homologue of mitochondrial alternative oxidase. Our results suggest that a co-ordinated induction of metabolic and defense genes, coupled with the suppression of photosynthetic activity, can compensate for the lack of APX and CAT. In addition, our findings demonstrate that the plant genome has a high degree of plasticity and will respond differently to different stressful conditions, namely, lack of APX, lack of CAT, or lack of both APX and CAT. PMID:12410811

  10. Evidence for separate substrate binding sites for hydrogen peroxide and cumene hydroperoxide (CHP) in the oxidation of ethanol by catalase

    SciTech Connect

    DeMaster, E.G.; Nagasawa,ss H.T.

    1986-03-01

    The oxidation of ethanol by purified bovine liver catalase (Sigma, C-40) can be supported by H/sub 2/O/sub 2/ or by CHP. The time course of the H/sub 2/O/sub 2/ supported reaction (using glucose/glucose oxidase as the H/sub 2/O/sub 2/ source) was linear for at least one hr, whereas the rate of acetaldehyde formation in the CHP (4.2 mM) supported reaction decreased with time. When catalase was exposed o CHP for 5 min before the addition of ethanol, the rate of CHP supported ethanol oxidation was reduced by more than 90% compared to incubations where the addition of ethanol preceded that of CHP. In the CHP inhibited state, the peroxidative activity of catalase was not restored by further addition of CHP or ethanol; however, addition of fresh catalase yielded its expected activity. Significantly, the CHP inhibited enzyme was equally effective as the untreated enzyme in catalyzing (a) the oxidation of ethanol in the presence H/sub 2/O/sub 2/ supported peroxidative activity as well as catalytic activity by CHP inhibited catalase points to separate binding sites for H/sub 2/O/sub 2/ and CHP in this reaction. Alternatively, CHP may bind adjacent to a common peroxide active site, thereby sterically impeding the binding of CHP - but not of H/sub 2/O/sub 2/ - to this active site.

  11. Ultraviolet Light B-Mediated Inhibition of Skin Catalase Activity Promotes Gr-1+CD11b+ Myeloid Cell Expansion

    PubMed Central

    Sullivan, Nicholas J.; Tober, Kathleen L.; Burns, Erin M.; Schick, Jonathan S.; Riggenbach, Judith A.; Mace, Thomas A.; Bill, Matthew A.; Young, Gregory S.; Oberyszyn, Tatiana M.; Lesinski, Gregory B.

    2011-01-01

    Skin cancer incidence and mortality are higher in men compared to women, but the causes of this sex discrepancy remain largely unknown. Ultraviolet light exposure induces cutaneous inflammation and neutralizes cutaneous antioxidants. Gr-1+CD11b+ myeloid cells are heterogeneous bone marrow-derived cells that promote inflammation-associated carcinogenesis. Reduced activity of catalase, an antioxidant present within skin, has been associated with skin carcinogenesis. We utilized the outbred, immune competent Skh-1 hairless mouse model of ultraviolet light B (UVB)-induced inflammation and non-melanoma skin cancer to further define sex discrepancies in UVB-induced inflammation. Our results demonstrated that male skin had relatively lower baseline catalase activity, which was inhibited following acute UVB exposure in both sexes. Further analysis revealed that skin catalase activity inversely correlated with splenic Gr-1+CD11b+ myeloid cell percentage. Acute UVB exposure induced Gr-1+CD11b+ myeloid cell skin infiltration, which was inhibited to a greater extent in males by topical catalase treatment. In chronic UVB studies, we demonstrated that the percentage of splenic Gr-1+CD11b+ myeloid cells was 55% higher in male tumor-bearing mice compared to their female counterparts. Together, our findings indicate that lower skin catalase activity in male mice may at least in part contribute to increased UVB-induced Gr-1+CD11b+ myeloid cells and subsequent skin carcinogenesis. PMID:22030957

  12. [Effect of afobazole on the accumulation of free radical oxidation products and the catalase activity in rats with cerebral ischemia].

    PubMed

    Silkina, I V; Zenina, T A; Seredenin, S B; Mirzoian, R S

    2006-01-01

    The influence of afobazole on the accumulation of free radical oxidation products (reactive oxygen species, ROS) and on the activity of antioxidative enzyme catalase was studied in striatum and cortex of rats under cerebral ischemia damage conditions. Afobazole showed a tendency to decrease the extent of ROS accumulation in the cortex. In striatum, the intensity of ROS accumulation in rats after ischemia wasa reliably lower as compared to that in control rats, but afobazole produced a partial recovery of this parameter. Afobazole induced an increase in the catalase activity in the cortex of rats with ischemia. In contrast, afobazole did not change the activity of this enzyme in striatum (where it was also decreased by ischemia). Thus, afobazole increased the resistance of neuron membrane structures to free radical oxidation in cortex and striatum and stimulated the catalase activity in the cortex in rats with global reversible cerebral ischernia. PMID:16995439

  13. The structure of coral allene oxide synthase reveals a catalase adapted for metabolism of a fatty acid hydroperoxide

    PubMed Central

    Oldham, Michael L.; Brash, Alan R.; Newcomer, Marcia E.

    2005-01-01

    8R-Lipoxygenase and allene oxide synthase (AOS) are parts of a naturally occurring fusion protein from the coral Plexaura homomalla. AOS catalyses the production of an unstable epoxide (an allene oxide) from the fatty acid hydroperoxide generated by the lipoxygenase activity. Here, we report the structure of the AOS domain and its striking structural homology to catalase. Whereas nominal sequence identity between the enzymes had been previously described, the extent of structural homology observed was not anticipated, given that this enzyme activity had been exclusively associated with the P450 superfamily, and conservation of a catalase fold without catalase activity is unprecedented. Whereas the heme environment is largely conserved, the AOS heme is planar and the distal histidine is flanked by two hydrogen-bonding residues. These critical differences likely facilitate the switch from a catalatic activity to that of a fatty acid hydroperoxidase. PMID:15625113

  14. Effects of molecular oxygen on detection of superoxide radical with nitroblue tetrazolium and on activity stains for catalase

    SciTech Connect

    Clare, D.A.; Duong, M.N.; Darr, D.; Archibald, F.; Fridovich, I.

    1984-08-01

    The usual method of staining polyacrylamide gel electropherograms for superoxide dismutase activity utilizes a photochemical flux of O/sub 2//sup -/ to reduce nitroblue tetrazolium. Superoxide dismutases intercept O/sub 2//sup -/, preventing formazan production and thus causing achromatic bands. In the presence of H/sub 2/O/sub 2/, catalase also yield achromatic bands during this staining procedure. This is due to local elevation of pO/sub 2/ by the catalytic decomposition of H/sub 2/O/sub 2/. O/sub 2/, in turn, inhibits the reduction of the tetrazolium by O/sub 2//sup -/. This phenomenon provides a new activity stain for catalase. A previously described activity stain for catalase has also been reexamined and significantly improved.

  15. Crystallization and preliminary X-ray diffraction analysis of a cold-adapted catalase from Vibrio salmonicida

    SciTech Connect

    Riise, Ellen Kristin [The Norwegian Structural Biology Centre, Faculty of Science, University of Tromsø, N-9037 Tromsø (Norway); Lorentzen, Marit Sjo [Department of Molecular Biotechnology, Institute of Medical Biology, Faculty of Medicine, University of Tromsø, N-9037 Tromsø (Norway); Helland, Ronny [The Norwegian Structural Biology Centre, Faculty of Science, University of Tromsø, N-9037 Tromsø (Norway); Willassen, Nils Peder, E-mail: nilspw@fagmed.uit.no [The Norwegian Structural Biology Centre, Faculty of Science, University of Tromsø, N-9037 Tromsø (Norway); Department of Molecular Biotechnology, Institute of Medical Biology, Faculty of Medicine, University of Tromsø, N-9037 Tromsø (Norway)

    2006-01-01

    Monoclinic (P2{sub 1}) crystals of a His-tagged form of V. salmonicida catalase without cofactor diffract X-rays to 1.96 Å. Catalase (EC 1.11.1.6) catalyses the breakdown of hydrogen peroxide to water and molecular oxygen. Recombinant Vibrio salmonicida catalase (VSC) possesses typical cold-adapted features, with higher catalytic efficiency, lower thermal stability and a lower temperature optimum than its mesophilic counterpart from Proteus mirabilis. Crystals of VSC were produced by the hanging-drop vapour-diffusion method using ammonium sulfate as precipitant. The crystals belong to the monoclinic space group P2{sub 1}, with unit-cell parameters a = 98.15, b = 217.76, c = 99.28 Å, ? = 110.48°. Data were collected to 1.96 Å and a molecular-replacement solution was found with eight molecules in the asymmetric unit.

  16. The Distribution of Catalase Activity, Isozyme Protein, and Transcript in the Tissues of the Developing Maize Seedling 1

    PubMed Central

    Redinbaugh, Margaret G.; Sabre, Mara; Scandalios, John G.

    1990-01-01

    The catalase activity, CAT-2 and CAT-3 isozyme protein levels, and the steady-state mRNA levels for each of the three catalase genes were determined in the scutellum, root, epicotyl, and leaf of the developing maize (Zea mays L.) seedling. Catalase activity was highest in the scutellum, with 10-fold lower enzyme activity in the leaf and epicotyl. Very low levels of catalase activity were found in the root. The highest levels of CAT-2 protein were found in the scutellum, with about 10-fold lower levels in the green leaf. CAT-2 protein was present in trace amounts early in root development and no CAT-2 protein was detected in the epicotyl. Shortly after germination, CAT-3 protein was present at high levels in both the epicotyl and green leaf. With development, the amount of CAT-3 protein decreased slowly in the epicotyl and rapidly in the green leaf. Low levels of this isozyme were detected in the scutellum and root. The Cat1 transcript accumulated to low levels in all four tissues during the 14 day developmental period. High levels of the Cat2 transcript were found in the scutellum, with moderate levels of the mRNA in the green leaf. The Cat2 transcript levels were very low in the root and epicotyl. While the Cat3 mRNA level in the scutellum was low, high levels of the Cat3 transcript were detected in the root, epicotyl, and leaf. There was a positive correlation between the accumulation of a catalase isozyme and its transcript, indicating that the tissue specificity of maize catalase gene expression was regulated pretranslationally. Images Figure 3 Figure 4 PMID:16667285

  17. Evaluation of a catalase-based method for estimating the shelf-life of pasteurized whole milk 

    E-print Network

    Dill, Susan Lee

    1988-01-01

    EVALUATION OF A CATALASE-BASED METHOD FOR ESTIMATING THE SHELF-LIFE OF PASTEURIEED WHOLE MIIK A Thesis by SUSAN LEE DI LL Submitted to the Graduate College of Texas A&M University in partial fulfillment of the requirements for the degree... of MASTER OF SCIENCE August 1988 Major Subject: Food Science and Technology EVALUATION OF A CATALASE-BASED METHOD FOR ESTIMATING THE SHELF-LIFE OP PASTEURIEED WHOLE MILK A Thesis by SUSAN LEE DILL Approved as to style and content by: Ronald L...

  18. Catalase HPI influences membrane permeability in Escherichia coli following near-UV stress

    SciTech Connect

    Leven, S.; Heimberger, A.; Eisenstark, A. (Univ. of Missouri, Columbia (USA))

    1990-09-28

    The katG gene in Escherichia coli encodes catalase HPI, which is involved in membrane transport and protects the cell during oxidative stress. Hydrogen peroxide (H2O2) induces synthesis of HPI. We examined the role of HPI in membrane permeability (proline uptake) following exposure to near-ultraviolet radiation (NUV). We found that NUV resulted in the same type of induction as H2O2. KatG::Tn10 cells experienced a large drop in uptake after NUV exposure, and levels remained low following incubation. A strain carrying a katG+ plasmid, however, showed considerably less decrease in uptake after NUV, and uptake quickly resumed upon incubation. Further, in an srd mutant which lacks 4-thiouracil, NUV resulted in only a small drop in proline uptake, which was immediately resumed.

  19. Sixty years from discovery to solution: crystal structure of bovine liver catalase form III

    SciTech Connect

    Foroughi, Leila M.; Kang, You-Na; Matzger, Adam J. (Michigan)

    2012-03-27

    The crystallization and structural characterization of bovine liver catalase (BLC) has been intensively studied for decades. Forms I and II of BLC have previously been fully characterized using single-crystal X-ray diffraction. Form III has previously been analyzed by electron microscopy, but owing to the thinness of this crystal form an X-ray crystal structure had not been determined. Here, the crystal structure of form III of BLC is presented in space group P212121, with unit-cell parameters a = 68.7, b = 173.7, c = 186.3 {angstrom}. The asymmetric unit is composed of the biological tetramer, which is packed in a tetrahedron motif with three other BLC tetramers. This higher resolution structure has allowed an assessment of the previously published electron-microscopy studies.

  20. Catalase-positive microperoxisomes in rat soleus and extensor digitorum longus muscle fiber types

    NASA Technical Reports Server (NTRS)

    Riley, Danny A.; Bain, James L. W.; Ellis, Stanley

    1988-01-01

    The size, distribution, and content of catalase-reactive microperoxisomes were investigated cytochemically in three types of muscle fibers from the soleus and the extensor digitorum longus (EDL) of male rats. Muscle fibers were classified on the basis of the mitochondrial content and distribution, the Z-band widths, and the size and shape of myofibrils as the slow-twitch oxidative (SO), the fast-twitch oxidative glycolytic (FOG), and the fast-twitch glycolytic (FG) fibers. It was found that both the EDL and soleus SO fibers possessed the largest microperoxisomes. A comparison of microperoxisome number per muscle fiber area or the microperoxisome area per fiber area revealed following ranking, starting from the largest number and the area-ratio values: soleus SO, EDL SO, EDL FOG, and EDL FG.

  1. Spectroscopic investigations on the interaction between carbon nanotubes and catalase on molecular level.

    PubMed

    Guan, Jin; Dai, Jingping; Zhao, Xingchen; Liu, Chunhua; Gao, Canzhu; Liu, Rutao

    2014-05-01

    The interactions between well-dispersed multiwalled carbon nanotubes (MWCNTs) and catalase (CAT) were investigated. The activity of CAT was inhibited with the addition of MWCNTs. After deducting the inner filter effect, the fluorescence spectra revealed that the tryptophan (Trp) residues were exposed and the fluorescence intensities of CAT increased with the increase in the MWCNTs concentration. At the same time, the environment of the Trp residues became more hydrophobic. The results of UV-vis absorption spectroscopy and CD spectra indicated that the secondary structure of CAT had been changed, and the amino acid residues were located in a more hydrophobic environment. Meanwhile, the UV-vis spectra indicated that the conformation of the heme porphyrin rings was changed. The microenvironment of CAT activity sites may be interfered by MWCNTs. This research showed that MWCNTs could not only contribute to the conformational changes of protein but also change the enzyme function. PMID:24616245

  2. Lack of effect of deferoxamine, dimethyl sulfoxide, and catalase on monocrotaline pyrrole pulmonary injury

    SciTech Connect

    Bruner, L.H.; Johnson, K.; Carpenter, L.J.; Roth, R.A.

    1987-01-01

    Monocrotaline pyrrole (MCTP) is a reactive metabolite of the pyrrolizidine alkaloid monocrotaline. MCTP given intravenously to rats causes pulmonary hypertension and right ventricular hypertrophy. Lesions in lungs after MCTP treatment contain macrophages and neutrophils, which may contribute to the damage by generation of reactive oxygen metabolites. Rats were treated with MCTP and agents known to protect against oxygen radical-mediated damage in acute models of neutrophil-dependent lung injury. Rats received MCTP and deferoxamine mesylate (DF), dimethyl sulfoxide (DMSO), or polyethylene glycol-coupled catalase (PEG-CAT). MCTP/vehicle-treated controls developed lung injury manifested as increased lung weight, release of lactate dehydrogenase into the airway, and sequestration of SVI-labeled bovine serum albumin in the lungs. Cotreatment of rats with DF, DMSO, or PEG-CAT did not protect against the injury due to MCTP. These results suggest that toxic oxygen metabolites do not play an important role in the pathogenesis of MCTP-induced pulmonary injury.

  3. Molecular interaction of 2-mercaptobenzimidazole with catalase reveals a potentially toxic mechanism of the inhibitor.

    PubMed

    Teng, Yue; Zou, Luyi; Huang, Ming; Zong, Wansong

    2014-12-01

    2-Mercaptobenzimidazole (MBI) is widely utilized as a corrosion inhibitor, copper-plating brightener and rubber accelerator. The residue of MBI in the environment possesses a potential risk to human health. In this work, the toxic interaction of MBI with the important antioxidant enzyme catalase (CAT) was investigated using spectroscopic and molecular docking methods under physiological conditions. MBI can spontaneously bind with CAT with one binding site through hydrogen bonds and van der Waals forces to form MBI-CAT complex. The molecular docking study revealed that MBI bound into the CAT interface of chains B and C, which led to some conformational and microenvironmental changes of CAT and further resulted in the inhibition of CAT activity. This present study provides direct evidence at a molecular level to show that exposure to MBI could induce changes in the structure and function of the enzyme CAT. PMID:25463673

  4. Evidence of catalase mimetic activity in Ce(3+)/Ce(4+) doped bioactive glasses.

    PubMed

    Nicolini, Valentina; Gambuzzi, Elisa; Malavasi, Gianluca; Menabue, Ledi; Menziani, Maria Cristina; Lusvardi, Gigliola; Pedone, Alfonso; Benedetti, Francesco; Luches, Paola; D'Addato, Sergio; Valeri, Sergio

    2015-03-12

    The ability of Ce-containing bioactive glasses to inhibit oxidative stress in terms of reduction of hydrogen peroxide, by mimicking the catalase enzyme activity is demonstrated here for the first time. The antioxidant properties of three bioactive glasses containing an increasing amount of CeO2 have been evaluated by following the degradation of hydrogen peroxide with time after immersion in H2O2 aqueous solutions with different concentration. XPS and UV-vis measurements allowed us to determine the Ce(3+)/Ce(4+) ratio in the bulk and on the glass surface, and to correlate it with the ability of the samples to show catalase mimetic activity. Interestingly, we have found that the bioactive glass with composition 23.2Na2O-25.7CaO-43.4SiO2-2.4P2O5-5.3CeO2 immersed in 0.1 M H2O2 aqueous solution is able to degrade 90% of it in 1 week. The reduction in bioactivity of the glasses with increasing CeO2 content is here rationalized in terms of a lower amount of phosphate groups available for the hydroxyapatite layer formation, after binding with cerium ions. In fact, classical molecular dynamics simulations revealed that the addition of CeO2 leads to the formation of cerium phosphate rich regions. The formation of an insoluble CePO4 crystalline phase is also observed by XRD analysis after thermal treatment of the glass samples. PMID:25710332

  5. Differential effects of superoxide dismutase and superoxide dismutase/catalase mimetics on human breast cancer cells.

    PubMed

    Shah, Manisha H; Liu, Guei-Sheung; Thompson, Erik W; Dusting, Gregory J; Peshavariya, Hitesh M

    2015-04-01

    Reactive oxygen species (ROS) such as superoxide and hydrogen peroxide (H2O2) have been implicated in development and progression of breast cancer. In the present study, we have evaluated the effects of the superoxide dismutase (SOD) mimetic MnTmPyP and the SOD/catalase mimetic EUK 134 on superoxide and H2O2 formation as well as proliferation, adhesion, and migration of MCF-7 and MDA-MB-231 cells. Superoxide and H2O2 production was examined using dihydroethidium and Amplex red assays, respectively. Cell viability and adhesion were measured using a tetrazolium-based MTT assay. Cell proliferation was determined using trypan blue assay. Cell cycle progression was analyzed using flow cytometry. Clonal expansion of a single cell was performed using a colony formation assay. Cell migration was measured using transwell migration assay. Dual luciferase assay was used to determine NF-?B reporter activity. EUK 134 effectively reduced both superoxide and H2O2, whereas MnTmPyP removed superoxide but enhanced H2O2 formation. EUK 134 effectively attenuated viability, proliferation, clonal expansion, adhesion, and migration of MCF-7 and MDA-MB-231 cells. In contrast, MnTmPyP only reduced clonal expansion of MCF-7 and MDA-MB-231 cells but had no effect on adhesion and cell cycle progression. Tumor necrosis factor-alpha-induced NF-?B activity was reduced by EUK 134, whereas MnTmPyP enhanced this activity. These data indicate that the SOD mimetic MnTmPyP and the SOD/catalase mimetic EUK 134 exert differential effects on breast cancer cell growth. Inhibition of H2O2 signaling using EUK 134-like compound might be a promising approach to breast cancer therapy. PMID:25794772

  6. Upregulation of Parkin in Endophilin Mutant Mice

    PubMed Central

    Cao, Mian; Milosevic, Ira; Giovedi, Silvia

    2014-01-01

    Several proteins encoded by PD genes are implicated in synaptic vesicle traffic. Endophilin, a key factor in the endocytosis of synaptic vesicles, was shown to bind to, and be ubiquitinated by, the PD-linked E3 ubiquitin ligase Parkin. Here we report that Parkin's level is specifically upregulated in brain and fibroblasts of endophilin mutant mice due to increased transcriptional regulation. Studies of transfected HEK293T cells show that Parkin ubiquitinates not only endophilin, but also its major binding partners, dynamin and synaptojanin 1. These results converge with the recently reported functional relationship of endophilin to the PD gene LRRK2 and with the identification of a PD-linked synaptojanin 1 mutation, in providing evidence for a link between PD and endocytosis genes. PMID:25471590

  7. Effects of some environmental parameters on catalase activity measured in the mussel ( Mytilus galloprovincialis) exposed to lindane

    Microsoft Academic Search

    Asma Khessiba; Michèle Roméo; Patricia Aïssa

    2005-01-01

    Mussels (Mytilus galloprovincialis), collected from the Bizerta lagoon, were acclimated for four days to various conditions of temperature, salinity, photoperiod and food supply and then exposed to lindane at a concentration of 40?gl?1. Catalase activity, which is a biomarker of exposure to an oxidative stress, was measured in the whole soft tissues of control and assay groups. In control mussels,

  8. Effects of molecular oxygen on detection of superoxide radical with nitroblue tetrazolium and on activity stains for catalase

    Microsoft Academic Search

    D. A. Clare; M. N. Duong; D. Darr; F. Archibald; I. Fridovich

    1984-01-01

    The usual method of staining polyacrylamide gel electropherograms for superoxide dismutase activity utilizes a photochemical flux of Oâ⁻ to reduce nitroblue tetrazolium. Superoxide dismutases intercept Oâ⁻, preventing formazan production and thus causing achromatic bands. In the presence of HâOâ, catalase also yield achromatic bands during this staining procedure. This is due to local elevation of pOâ by the catalytic decomposition

  9. The induction of human superoxide dismutase and catalase in vivo: a fundamentally new approach to antioxidant therapy.

    PubMed

    Nelson, Sally K; Bose, Swapan K; Grunwald, Gary K; Myhill, Paul; McCord, Joe M

    2006-01-15

    A composition consisting of extracts of five widely studied medicinal plants (Protandim) was administered to healthy human subjects ranging in age from 20 to 78 years. Individual ingredients were selected on the basis of published findings of induction of superoxide dismutase (SOD) and/or catalase in rodents in vivo, combined with evidence of decreasing lipid peroxidation. Each ingredient was present at a dosage sufficiently low to avoid any accompanying unwanted pharmacological effects. Blood was analyzed before supplementation and after 30 and 120 days of supplementation (675 mg/day). Erythrocytes were assayed for SOD and catalase, and plasma was assayed for lipid peroxidation products as thiobarbituric acid-reacting substances (TBARS), as well as uric acid, C-reactive protein, and cholesterol (total, LDL, and HDL). Before supplementation, TBARS showed a strong age-dependent increase. After 30 days of supplementation, TBARS declined by an average of 40% (p = 0.0001) and the age-dependent increase was eliminated. By 120 days, erythrocyte SOD increased by 30% (p < 0.01) and catalase by 54% (p < 0.002). We conclude that modest induction of the catalytic antioxidants SOD and catalase may be a much more effective approach than supplementation with antioxidants (such as vitamins C and E) that can, at best, stoichiometrically scavenge a very small fraction of total oxidant production. PMID:16413416

  10. Original Contribution The induction of human superoxide dismutase and catalase in vivo: A fundamentally new approach to antioxidant therapy

    Microsoft Academic Search

    Sally K. Nelson; Swapan K. Bose; Gary K. Grunwald; Paul Myhill; Joe M. McCord

    A composition consisting of extracts of five widely studied medicinal plants (Protandim) was administered to healthy human subjects ranging in age from 20 to 78 years. Individual ingredients were selected on the basis of published findings of induction of superoxide dismutase (SOD) and\\/or catalase in rodents in vivo, combined with evidence of decreasing lipid peroxidation. Each ingredient was present at

  11. The induction of human superoxide dismutase and catalase in vivo: A fundamentally new approach to antioxidant therapy

    Microsoft Academic Search

    Sally K. Nelson; Swapan K. Bose; Gary K. Grunwald; Paul Myhill; Joe M. McCord

    2006-01-01

    A composition consisting of extracts of five widely studied medicinal plants (Protandim) was administered to healthy human subjects ranging in age from 20 to 78 years. Individual ingredients were selected on the basis of published findings of induction of superoxide dismutase (SOD) and\\/or catalase in rodents in vivo, combined with evidence of decreasing lipid peroxidation. Each ingredient was present at

  12. Superoxide dismutase, catalase and acetylcholinesterase: biomarkers for the joint effects of cadmium, zinc and methyl parathion contamination in water

    Microsoft Academic Search

    XuePing Ling; YiHeng Zhang; YingHua Lu; HeQing Huang

    2011-01-01

    Heavy metals are known to reduce the activities of antioxidant enzymes (e.g. superoxide dismutase, catalase), while organophosphorous insecticides are known to inhibit the activity of the enzyme acetylcholinesterase. In this study, the activities of these three enzymes in zebrafish (Danio rerio) tissues were assessed to evaluate the consequences heavy metal and organophosphate contamination in aquatic systems. When the fish were

  13. 232 1\\'1. POLONOVSKI. -L'AMMONIAQUE catalase n'est pas forte et s'exprime volumtrique ment par 0,5-1,0.

    E-print Network

    Boyer, Edmond

    232 1\\'1. POLONOVSKI. - L'AMMONIAQUE catalase n'est pas forte et s'exprime volumétrique ment par 0,5-1,0. 3. La catalase ne peut pas servir à la définition -de la qualité du levainlactique. BIBLIOGRAPHIE

  14. Two inducers of plant defense responses, 2,6-dichloroisonicotinec acid and salicylic acid, inhibit catalase activity in tobacco.

    PubMed Central

    Conrath, U; Chen, Z; Ricigliano, J R; Klessig, D F

    1995-01-01

    2,6-Dichloroisonicotinic acid (INA) and salicylic acid (SA) are potent inducers of plant defense responses including the synthesis of pathogenesis-related (PR) proteins and the development of enhanced disease resistance. A soluble SA-binding protein has been purified from tobacco with an affinity and specificity of binding that suggest it is a SA receptor. Recently, this protein has been shown to be a catalase whose enzymatic activity is inhibited by SA binding. We have proposed that the resulting increase in intracellular levels of reactive oxygen species plays a role in the induction of defense responses such as PR protein gene expression. Here we report that INA, like SA, binds the SA-binding protein/catalase and inhibits its enzymatic activity. In fact, the dose-response curves for inhibition of catalase by these two compounds are similar. Furthermore, the ability of both INA analogues and SA derivatives to bind and inhibit tobacco catalase correlates with their biological activity to induce PR-1 gene expression and enhance resistance to tobacco mosaic virus. Comparison of the structures of INA, SA, and their analogues reveals several common features that appear to be important for biological activity. Thus, these results not only suggest that INA and SA share the same mechanism of action that involves binding and inhibition of catalase but also further indicate an important role for reactive oxygen species in the induction of certain plant defense responses. This is supported by the demonstration that INA-mediated PR-1 gene activation is suppressed by antioxidants. Images Fig. 2 Fig. 3 PMID:11607566

  15. Failure of catalase to protect against aflatoxin B{sub 1}-induced mouse lung tumorigenicity

    SciTech Connect

    Guindon, Katherine A. [Department of Pharmacology and Toxicology, Queen's University, Kingston, Ontario, K7L 3N6 (Canada); Foley, Julie F.; Maronpot, Robert R. [National Institute of Environmental Health Sciences, Research Triangle Park, NC 27709 (United States); Massey, Thomas E. [Department of Pharmacology and Toxicology, Queen's University, Kingston, Ontario, K7L 3N6 (Canada)], E-mail: masseyt@queensu.ca

    2008-03-01

    The carcinogenic mycotoxin aflatoxin B{sub 1} (AFB{sub 1}) induces 8-hydroxy-2'-deoxyguanosine (8-OHdG) formation in mouse lung, an effect that can be prevented by treatment with polyethylene glycol-conjugated catalase (PEG-CAT). G {yields} T transversion mutation in K-ras, an early event in AFB{sub 1}-induced mouse lung carcinogenesis, is thought to result from AFB{sub 1}-8,9-exo-epoxide binding to DNA to form AFB{sub 1}-N{sup 7}-guanine, but may also result from formation of 8-OHdG. Therefore, oxidative DNA damage may be important in AFB{sub 1} carcinogenicity. The objective of this study was to determine whether PEG-CAT would prevent AFB{sub 1} tumorigenicity. Mouse lung tumorigenesis was assessed following treatment of female A/J mice with 300 kU/kg PEG-CAT ip and/or 50 mg/kg AFB{sub 1}. Mice were killed 7 months post-treatment and tumors greater than 1 mm in diameter were excised. Unexpectedly, the mean number of tumors per mouse in the PEG-CAT + AFB{sub 1} group (8.81 {+-} 3.64, n = 47) was greater than that of the group treated with AFB{sub 1} alone (7.05 {+-} 3.45, n = 42) (P < 0.05). The tumors obtained from mice treated with PEG-CAT + AFB{sub 1} were larger than those from mice treated with AFB{sub 1} alone (P < 0.05). There was no difference in K-ras exon 1 mutation spectrum or in the histological diagnosis of tumors between AFB{sub 1} and PEG-CAT + AFB{sub 1} groups (P > 0.05). In vitro incubation with mouse liver catalase (CAT) resulted in conversion of [{sup 3}H]AFB{sub 1} into a DNA-binding species, a possible explanation for the results observed in vivo. These results demonstrate that PEG-CAT is not protective against AFB{sub 1} carcinogenicity in mouse lung despite preventing DNA oxidation.

  16. Elevated hydrogen peroxide and decreased catalase and glutathione peroxidase protection are associated with aging sarcopenia

    PubMed Central

    2013-01-01

    Background Sarcopenia is the progressive loss of skeletal muscle that contributes to the decline in physical function during aging. A higher level of oxidative stress has been implicated in aging sarcopenia. The current study aims to determine if the higher level of oxidative stress is a result of increased superoxide (O2?) production by the NADPH oxidase (NOX) enzyme or decrease in endogenous antioxidant enzyme protection. Methods Female Balb/c mice were assigned to 4 age groups; 6, 12, 18 and 24 months. Body weight and animal survival rates were recorded over the course of the study. Skeletal muscle tissues were collected and used to measure NOX subunit mRNA, O2? levels and antioxidant enzymes. Results Key subunit components of NOX expression were elevated in skeletal muscle at 18 months, when sarcopenia was first evident. Increased superoxide dismutase 1 (SOD1) activity suggests an increase in O2? dismutation and this was further supported by elevated levels of hydrogen peroxide (H2O2) and decline in catalase and glutathione peroxidase (GPx) antioxidant protection in skeletal muscle at this time. NOX expression was also higher in skeletal muscle at 24 months, however this was coupled with elevated levels of O2? and a decline in SOD1 activity, compared to 6 and 12 months but was not associated with further loss of muscle mass. Conclusions While the source of ROS in sarcopenic muscle remains unknown, this study provides evidence that the NOX enzyme could be involved in ROS production by regulating superoxide in ageing muscles. This study also suggests that H2O2 is the key ROS in the onset of sarcopenia and that the decline in antioxidant protection by catalase and GPx is indicative of antioxidant dysfunction and may therefore be a major contributing factor in the development or onset of sarcopenia. Furthermore, the changes in ROS and antioxidant activity after sarcopenia was first evident gives some evidence for a compensatory mechanism, in response to insult, in order to maintain muscle integrity. PMID:24093947

  17. Study on the interaction of catalase with pesticides by flow injection chemiluminescence and molecular docking.

    PubMed

    Tan, Xijuan; Wang, Zhuming; Chen, Donghua; Luo, Kai; Xiong, Xunyu; Song, Zhenghua

    2014-08-01

    The interaction mechanisms of catalase (CAT) with pesticides (including organophosphates: disulfoton, isofenphos-methyl, malathion, isocarbophos, dimethoate, dipterex, methamidophos and acephate; carbamates: carbaryl and methomyl; pyrethroids: fenvalerate and deltamethrin) were first investigated by flow injection (FI) chemiluminescence (CL) analysis and molecular docking. By homemade FI-CL model of lg[(I0-I)/I]=lgK+nlg[D], it was found that the binding processes of pesticides to CAT were spontaneous with the apparent binding constants K of 10(3)-10(5) L mol(-1) and the numbers of binding sites about 1.0. The binding abilities of pesticides to CAT followed the order: fenvalerate>deltamethrin>disulfoton>isofenphos-methyl>carbaryl>malathion>isocarbophos>dimethoate>dipterex>acephate>methomyl>methamidophos, which was generally similar to the order of determination sensitivity of pesticides. The thermodynamic parameters revealed that CAT bound with hydrophobic pesticides by hydrophobic interaction force, and with hydrophilic pesticides by hydrogen bond and van der Waals force. The pesticides to CAT molecular docking study showed that pesticides could enter into the cavity locating among the four subdomains of CAT, giving the specific amino acid residues and hydrogen bonds involved in CAT-pesticides interaction. It was also found that the lgK values of pesticides to CAT increased regularly with increasing lgP, Mr, MR and MV, suggesting that the hydrophobicity and steric property of pesticide played essential roles in its binding to CAT. PMID:24875908

  18. PaCATB, a secreted catalase protecting Podospora anserina against exogenous oxidative stress

    PubMed Central

    Zintel, Sandra; Bernhardt, Dominik; Rogowska-Wrzesinska, Adelina; Osiewacz, Heinz D.

    2011-01-01

    A differential mass spectrometry analysis of secreted proteins from juvenile and senescent Podospora anserina cultures revealed age-related differences in protein profiles. Among other proteins with decreased abundance in the secretome of senescent cultures a catalase, termed PaCATB, was identified. Genetic modulation of the abundance of PaCATB identified differential effects on the phenotype of the corresponding strains. Deletion of PaCatB resulted in decreased resistance, over-expression in increased resistance against hydrogen peroxide. While the lifespan of the genetically modified strains was found to be unaffected under standard growth conditions, increased exogenous hydrogen peroxide stress in the growth medium markedly reduced the lifespan of the PaCatB deletion strain but extended the lifespan of PaCatB over-expressors. Overall our data identify a component of the secretome of P. anserina as a new effective factor to cope with environmental stress, stress that under natural conditions is constantly applied on organisms and influences aging processes. PMID:21865610

  19. Determination of the intrinsic kinetic constants of immobilized glucose oxidase and catalase.

    PubMed

    Tse, P H; Leypoldt, J K; Gough, D A

    1987-04-01

    Models of membrane systems containing immobilized glucose oxidase and catalase operating together or independently have been developed. A rotated disk electrode apparatus was employed with novel electrochemical operating conditions to experimentally determine mass transfer and intrinsic kinetic parameters of enzyme-containing membranes. The value of a mass transfer parameter that describes internal and external diffusion was first determined under conditions that do not permit the enzyme reactions. In a subsequent experiment with the reaction allowed, kinetic parameters corresponding to the intrinsic maximal velocity and Michaelis constants of the immobilized enzymes were estimated by regression analysis of data based on an appropriate two- or three- parameter model. It was found that immobilization reduced the maximal intrinsic velocity but had no detectable effect on the Michaelis constants. In all but one case- these methods for membrane characterization are nondestructive and can be used repeatedly on a given membrane. These techniques provide the means for quantitative comparisons of immobilization methods and make possible temporal studies of immobilized enzyme inactivation. PMID:18576504

  20. Effects of humic acid-metal complexes on hepatic carnitine palmitoyltransferase, carnitine acetyltransferase and catalase activities

    SciTech Connect

    Fungjou Lu; Youngshin Chen (National Taiwan Univ., Taipei (Taiwan, Province of China). Dept. of Biochemistry); Tienshang Huang (National Taiwan Univ., Taipei (Taiwan, Province of China). Dept. of Medicine)

    1994-03-01

    A significant increase in activities of hepatic carnitine palmitoyltransferase and carnitine acetyltransferase was observed in male Balb/c mice intraperitoneally injected for 40 d with 0.125 mg/0.1 ml/d humic acid-metal complexes. Among these complexes, the humic acid-As complex was relatively effective, whereas humic acid-25 metal complex was more effective, and humic acid-26 metal complex was most effective. However, humic acid or metal mixtures, or metal such as As alone, was not effective. Humic acid-metal complexes also significantly decreased hepatic catalase activity. A marked decrease of 60-kDa polypeptide in liver cytoplasm was also observed on SDS-polyacrylamide gel electrophoresis after the mice had been injected with the complexes. Morphological analysis of a histopathological biopsy of such treated mice revealed several changes in hepatocytes, including focal necrosis and cell infiltration, mild fatty changes, reactive nuclei, and hypertrophy. Humic acid-metal complexes affect activities of metabolic enzymes of fatty acids, and this results in accumulation of hydrogen peroxide and increase of the lipid peroxidation. The products of lipid peroxidation may be responsible for liver damage and possible carcinogenesis. Previous studies in this laboratory had shown that humic acid-metal complex altered the coagulation system and that humic acid, per se, caused vasculopathy. Therefore, humic acid-metal complexes may be main causal factors of not only so-called blackfoot disease, but also the liver cancer prevailing on the southwestern coast of Taiwan.

  1. Catalase overexpression in aortic smooth muscle prevents pathological mechanical changes underlying abdominal aortic aneurysm formation

    PubMed Central

    Maiellaro-Rafferty, Kathryn; Weiss, Daiana; Joseph, Giji; Wan, William; Gleason, Rudolph L.

    2011-01-01

    The causality of the associations between cellular and mechanical mechanisms of abdominal aortic aneurysm (AAA) formation has not been completely defined. Because reactive oxygen species are established mediators of AAA growth and remodeling, our objective was to investigate oxidative stress-induced alterations in aortic biomechanics and microstructure during subclinical AAA development. We investigated the mechanisms of AAA in an angiotensin II (ANG II) infusion model of AAA in apolipoprotein E-deficient (apoE?/?) mice that overexpress catalase in vascular smooth muscle cells (apoE?/?xTgSMC-Cat). At baseline, aortas from apoE?/?xTgSMC-Cat exhibited increased stiffness and the microstructure was characterized by 50% more collagen content and less elastin fragmentation. ANG II treatment for 7 days in apoE?/? mice altered the transmural distribution of suprarenal aortic circumferential strain (quantified by opening angle, which increased from 130 ± 1° at baseline to 198 ± 8° after 7 days of ANG II treatment) without obvious changes in the aortic microstructure. No differences in aortic mechanical behavior or suprarenal opening angle were observed in apoE?/?xTgSMC-Cat after 7 days of ANG II treatment. These data suggest that at the earliest stages of AAA development H2O2 is functionally important and is involved in the control of local variations in remodeling across the vessel wall. They further suggest that reduced elastin integrity at baseline may predispose the abdominal aorta to aneurysmal mechanical remodeling. PMID:21551275

  2. Bioaccumulation of fullerene (C60) and corresponding catalase elevation in Lumbriculus variegatus.

    PubMed

    Wang, Jiafan; Wages, Mike; Yu, Shuangying; Maul, Jonathan D; Mayer, Greg; Hope-Weeks, Louisa; Cobb, George P

    2014-05-01

    Fullerene (C(60)), with its unique physical properties and nanometer size, has been mass-produced for many applications in recent decades. The increased likelihood of direct release into the environment has raised interest in understanding both the environmental fate and corresponding biological effects of fullerenes to living organisms. Because few studies have emphasized fullerene uptake and resulting biochemical responses by living organisms, a toxicity screening test and a 28-d bioaccumulation test for Lumbriculus variegatus were performed. No mortality was observed in the range of 0.05?mg?C(60) /kg dry sediment to 11.33?mg?C(60) /kg dry sediment. A biota-sediment accumulation factor of micron-sized fullerene agglomerates (µ-C(60)) was 0.032?±?0.008 at day 28, which is relatively low compared with pyrene (1.62?±?0.22). Catalase (CAT) activity, an oxidative stress indicator, was elevated significantly on day 14 for L. variegatus exposed to µ-C(60) (p?=?0.034). This peak CAT activity corresponded to the highest body residues observed in the present study, 199?±?80?µg?C(60) /kg dry weight sediment. Additionally, smaller C(60) agglomerate size increased bioaccumulation potential in L. variegatus. The relationship between C(60) body residue and the increased CAT activity followed a linear regression. All results suggest that C(60) has a lower bioaccumulation potential than pyrene but a higher potential to induce oxidative stress in L. variegatus. PMID:24477927

  3. Potential toxicity of sarafloxacin to catalase: Spectroscopic, ITC and molecular docking descriptions

    NASA Astrophysics Data System (ADS)

    Cao, Zhaozhen; Liu, Rutao; Yang, Bingjun

    2013-11-01

    The interaction between sarafloxacin and catalase (CAT) was studied by fluorescence spectroscopy, UV-visible absorption spectroscopy, circular dichroism (CD) spectroscopy, isothermal titration microcalorimetry (ITC) and molecular docking method. After deducting the inner filter effect, the fluorescence of CAT was quenched regularly by different concentrations of sarafloxacin. The quenching mechanism was studied by lifetime measurement, and it was proved to be mostly due to static quenching. The formation of sarafloxacin-CAT complex alters the micro-environment of amide moieties and tryptophan (Trp) residues, reduces the ?-helix content of the enzyme, changes the peripheral substituents on the porphyrin ring of heme and leads to the inhibition of the enzyme activity. Molecular docking study reveals that sarafloxacin is located between two ?-helix of CAT near to Trp 182 and Trp 185 residues, which supports the experimental results and helps to have a more clear understanding about the interaction mechanism. The change in the relative position of His 74 to heme induced by the variation of secondary structure is considered to be the major reason for the reduction of CAT activity. Moreover, sarafloxacin binds into a hydrophobic area of CAT mainly through hydrophobic interactions, which is consistent with the ITC analysis.

  4. Filamentous polymer nanocarriers of tunable stiffness that encapsulate the therapeutic enzyme catalase

    PubMed Central

    Simone, Eric A.; Dziubla, Thomas D.; Discher, Dennis E.; Muzykantov, Vladimir R.

    2009-01-01

    Therapeutic proteins are prone to inactivation by aggregation, proteases and natural inhibitors, motivating development of protective delivery systems. Here we focus on protective encapsulation of the potent antioxidant enzyme, catalase, by filamentous polymer nanocarriers (f-PNC), with the specific goal of addressing whether polymer molecular weight (MW) controls formation and structural properties such as size and stiffness. While maintaining the same MW ratio of polyethylene glycol (PEG) to polylactic acid (PLA), a series of PEG-b-PLA diblock copolymers were synthesized, with total MW ranging from about 10 kg/mol to 100 kg/mol. All diblocks formed f-PNC upon processing, which encapsulated active enzyme that proved resistant to protease degradation. Further, f-PNC stiffness, length, and thickness increased with increasing MW. Interestingly, heating above a polymer's glass transition temperature (<30°C) increased f-PNC flexibility. Thus we report here for the first time f-PNC that encapsulate an active enzyme with polymer MW-tunable flexibility, offering several potential therapeutic applications. PMID:19385657

  5. Expression of a cloned sweet potato catalase SPCAT1 alleviates ethephon-mediated leaf senescence and H?O? elevation.

    PubMed

    Chen, Hsien-Jung; Wu, Sin-Dai; Huang, Guan-Jhong; Shen, Che-Yu; Afiyanti, Mufidah; Li, Wei-Jhen; Lin, Yaw-Huei

    2012-01-01

    In this report a full-length cDNA, SPCAT1, was isolated from ethephon-treated mature L3 leaves of sweet potato. SPCAT1 contained 1479 nucleotides (492 amino acids) in its open reading frame, and exhibited high amino acid sequence identities (ca. 71.2-80.9%) with several plant catalases, including Arabidopsis, eggplant, grey mangrove, pea, potato, tobacco and tomato. Gene structural analysis showed that SPCAT1 encoded a catalase and contained a putative conserved internal peroxisomal targeting signal PTS1 motif and calmodulin binding domain around its C-terminus. RT-PCR showed that SPCAT1 gene expression was enhanced significantly in mature L3 and early senescent L4 leaves and was much reduced in immature L1, L2 and completely yellowing senescent L5 leaves. In dark- and ethephon-treated L3 leaves, SPCAT1 expression was significantly enhanced temporarily from 0 to 24h, then decreased gradually until 72h after treatment. SPCAT1 gene expression levels also exhibited approximately inverse correlation with the qualitative and quantitative H(2)O(2) amounts. Effector treatment showed that ethephon-enhanced SPCAT1 expression was repressed by antioxidant reduced glutathione, NADPH oxidase inhibitor diphenylene iodonium (DPI), calcium ion chelator EGTA and de novo protein synthesis inhibitor cycloheximide. These data suggest that elevated reactive oxygen species H(2)O(2), NADPH oxidase, external calcium influx and de novo synthesized proteins are required and associated with ethephon-mediated enhancement of sweet potato catalase SPCAT1 expression. Exogenous application of expressed catalase SPCAT1 fusion protein delayed or alleviated ethephon-mediated leaf senescence and H(2)O(2) elevation. Based on these data we conclude that sweet potato SPCAT1 is an ethephon-inducible peroxisomal catalase, and its expression is regulated by reduced glutathione, DPI, EGTA and cycloheximide. Sweet potato catalase SPCAT1 may play a physiological role or function in cope with H(2)O(2) homeostasis in leaves caused by developmental cues and environmental stimuli. PMID:21893366

  6. Disruption of the human pathogenic yeast Candida albicans catalase gene decreases survival in mouse-model infection and elevates susceptibility to higher temperature and to detergents.

    PubMed

    Nakagawa, Yoshiyuki; Kanbe, Toshio; Mizuguchi, Ikuyo

    2003-01-01

    Catalase-deficient strains of the human pathogenic yeast Candida albicans were constructed using the URA-blaster method. The disruptant was viable and grew normally in an ordinary culture condition, but became extremely sensitive to treatment with hydrogen peroxide. No catalase activity was observed in a catalase (CCT)-gene-disrupted strain, 1F5-4-1, suggesting that there were no other catalase or catalase-like enzymes in this yeast. The disruptant was shown to be sensitive to higher temperature and to low concentrations of SDS, NP-40, or Triton X-100. After a wild-type CCT gene was reintroduced into the disruptant, catalase activity was restored and the strain became moderately sensitive to treatment with hydrogen peroxide. However, neither the temperature sensitivity nor the susceptibility to SDS observed in the disruptant was restored in the CCT-reintroduced strain. A model infection experiment using wild-type and dCCT strains showed that the disruptants disappeared more rapidly than the wild-type strain in mouse liver, lung, and spleen. These results suggest that the catalase plays a significant role in survival in the host immune system and thus leads this organism to establish infection in the host. PMID:12906099

  7. Superoxide dismutase, catalase and acetylcholinesterase: biomarkers for the joint effects of cadmium, zinc and methyl parathion contamination in water.

    PubMed

    Ling, XuePing; Zhang, YiHeng; Lu, YingHua; Huang, HeQing

    2011-10-01

    Heavy metals are known to reduce the activities of antioxidant enzymes (e.g. superoxide dismutase, catalase), while organophosphorous insecticides are known to inhibit the activity of the enzyme acetylcholinesterase. In this study, the activities of these three enzymes in zebrafish (Danio rerio) tissues were assessed to evaluate the consequences heavy metal and organophosphate contamination in aquatic systems. When the fish were contacted with water containing a single pollutant, superoxide dismutase activity was affected by the presence of Cd but not by methyl parathion or Zn. However, catalase and acetylcholinesterase activities were sensitive to all three pollutants. The combined treatment showed that the three enzymes could be chosen as biomarkers of joint pollution by both metals and organophosphate. Toxicity tests showed an antagonism interaction between methyl parathion and Cd or Zn, and the change of enzyme activities at 96 hours was in accordance with that. PMID:22329136

  8. Dynamics of erythrocyte count, hemoglobin, and catalase activity in rat blood in hypokinesia, muscular activity and restoration

    NASA Technical Reports Server (NTRS)

    Taneyeva, G. V.; Potapovich, G. M.; Voloshko, N. A.; Uteshev, A. B.

    1980-01-01

    Tests were conducted to prove that muscular exertion (in this instance swimming) of different duration and intensity, as well as hypodynamia, result in an increase of hemoglobin and number of red blood cells in peripheral blood rats. Catalase activity increased with an increase in the duration of swimming, but only up to 6 hr; with 7-9 hr of swimming as well as in hypodynamia, catalase activity decreased. It was also observed that under hypodynamia as well as in 3, 5 and 6 hr exertion (swimming) the color index of blood decreased. Pressure chamber treatment (for 8 min each day for one week), alternating a 2 min negative pressure up to 35 mm Hg with 1 min positive pressure, increased the erythrocyte count and hemoglobin content.

  9. Biochemical biomarkers in environmental studies—lessons learnt from enzymes catalase, glutathione S -transferase and cholinesterase in two crustacean species

    Microsoft Academic Search

    Anita Jemec; Damjana Drobne; Tatjana Tišler; Kristina Sep?i?

    2010-01-01

    Background, aim and scope  For reliable environmental risk assessment of pollutants, knowledge on the effects at different levels of biological organisation\\u000a is needed. During the early days of biomarker research in environmental studies approximately two decades ago, biochemical\\u000a biomarkers were considered as the most promising tool for such purposes. Among these, three enzymes have often been studied:\\u000a catalase (CAT), glutathione S-transferase

  10. Effects of Single-Dose Ultraviolet Radiation on Skin Superoxide Dismutase, Catalase, and Xanthine Oxidase in Hairless Mice

    Microsoft Academic Search

    Barbara C. Pence; Mark F. Naylor

    1990-01-01

    The effects of a single exposure to UVB radiation on skin antioxidant enzymes and superoxide-generating xanthine oxidase were examined in Skh:HR-1 hairless mice. Significant decreases in superoxide dismutase (SOD) and catalase (CAT) were observed by 12 h after UV irradiation and remained depressed for up to 72 h. No induction of xanthine dehydrogenase (XD) or xanthine oxidase (XO) occurred with

  11. Cloning, expression and physiological analysis of broccoli catalase gene and Chinese cabbage ascorbate peroxidase gene under heat stress

    Microsoft Academic Search

    Kuan-Hung Lin; Ho-Chang Huang; Ching-Yun Lin

    2010-01-01

    The objectives of this work were to clone the catalase (CAT) gene from broccoli (Brassica oleracea) and the ascorbate peroxidase (APX) gene from Chinese cabbage and measure the regulation of CAT and APX gene expressions\\u000a under heat-stress conditions. Different genotypes responded differently to heat stress according to their various antioxidant\\u000a enzymes and physiological parameters. CAT and APX gene expression profiles

  12. Heme oxygenase and catalase gene expression in nodules and roots of soybean plants subjected to cadmium stress

    Microsoft Academic Search

    Karina B. Balestrasse; Gustavo G. Yannarelli; Guillermo O. Noriega; Alcira Batlle; Maria L. Tomaro

    2008-01-01

    Heme oxygenase (HO, EC 1.14.99.3) catalyses the oxidative conversion of heme to biliverdin IX? (BV) with the concomitant released\\u000a of carbon monoxide and iron. Recently, plant HOs have been involved in the defence mechanism against oxidative stress. The\\u000a goal of this study was to evaluate the time-course of HO-1 and catalase (CAT, EC 1.11.1.6) gene expressions in nodules and\\u000a roots

  13. Cloning, nucleotide sequence, and regulation of katE encoding a sigma B-dependent catalase in Bacillus subtilis.

    PubMed Central

    Engelmann, S; Lindner, C; Hecker, M

    1995-01-01

    A sigma B-dependent stress gene of Bacillus subtilis was localized downstream of the licS gene. The predicted amino acid sequence exhibited a significant similarity to the sequence of the katE-encoded catalase HPII of Escherichia coli, and we designated it the open reading frame katE. In a B. subtilis katE mutant, catalase 2 could not be detected. The amount of katE-specific mRNA was increased after heat, salt, or ethanol stress or after glucose starvation in a sigma B-dependent manner. As in E. coli, the transcription of the katE gene in B. subtilis was unaffected by the addition of H2O2 to exponentially growing cells. In contrast, the katA gene encoding catalase 1 of B. subtilis showed an induction pattern different from that of katE; katA expression was strongly increased by oxidative stress. The similarity between E. coli sigma S-dependent genes and B. subtilis sigma B-dependent genes suggests that both may confer multiple stress resistance to stationary-phase cells. PMID:7559348

  14. Manganese L-edge X-ray absorption spectroscopy of manganese catalase from Lactobacillus plantarum and mixed valence manganese complexes

    SciTech Connect

    Grush, M.M.; Chen, J.; George, S.J. [Univ. of California, Davis, CA (United States)] [and others] [Univ. of California, Davis, CA (United States); and others

    1996-01-10

    The first Mn L-edge absorption spectra of a Mn metalloprotein are presented in this paper. Both reduced and superoxidized Mn catalase have been examined by fluorescence-detected soft X-ray absorption spectroscopy, and their Mn L-edge spectra are dramatically different. The spectrum of reduced Mn(II)Mn(II) catalase has been interpreted by ligand field atomic multiplet calculations and by comparison to model compound spectra. The analysis finds a 10 Dq value of nearly 1.1 eV, consistent with coordination by predominately nitrogen and oxygen donor ligands. For interpretation of mixed valence Mn spectra, an empirical simulation procedure based on the addition of homovalent model compound spectra has been developed and was tested on a variety of Mn complexes and superoxidized Mn catalase. This routine was also used to determine the oxidation state composition of the Mn in [Ba{sub 8}Na{sub 2}ClMn{sub 16}(OH){sub 8}(CO{sub 3}){sub 4}L{sub 8}] .53 H{sub 2}O (L=1,3-diamino-2-hydroxypropane-N,N,N`N`-tetraacetic acid). 27 refs., 6 figs.

  15. Catalase inhibition into the fourth cerebral ventricle affects bradycardic parasympathetic response to increase in arterial pressure without changing the baroreflex.

    PubMed

    Valenti, Vitor E; De Abreu, Luiz Carlos; Sato, Monica A; Fonseca, Fernando L A; Riera, Andrés R Pérez; Ferreira, Celso

    2011-03-01

    Exogenous catalase influences neural control of cardiovascular system; however, we do not know yet if its inhibition into the fourth cerebral ventricle (4(th) V) influences baroreflex regulation. We evaluated the effects of central catalase inhibition on baroreflex in conscious Wistar rats. We used males Wistar rats (320-370 g), which were implanted with a stainless steel guide cannula into 4(th) V. The femoral artery and vein were cannulated for mean arterial pressure (MAP) and heart rate (HR) measurement and drug infusion, respectively. After basal MAP and HR recordings, the baroreflex was tested with a pressor dose of phenylephrine (PHE, 8 ?g/kg, bolus) and a depressor dose of sodium nitroprusside (SNP, 50 ?g/kg, bolus). Baroreflex was evaluated before 5, 15, 30 and 60 minutes after 3-amino-1, 2, 4-triazole (ATZ, 0.001 g/100 ?L) injection into the 4(th) V. Vehicle treatment did not change baroreflex responses. ATZ attenuated bradycardic peak and reduced HR range at 30 minutes. ATZ into the 4(th) V reduced bradycardic and tachycardic reflex responses to increase and decrease MAP, respectively (p<0.05) 30 minutes after its microinjection without significantly changing the basal MAP and HR. In conclusion, central catalase inhibition influenced the highest parasympathetic response to MAP increase in conscious Wistar rats without change baroreflex gain. PMID:21425479

  16. The effects of catalase inhibition into the fourth cerebral ventricle on the Bezold-Jarisch reflex in spontaneously hypertensive rats.

    PubMed

    Cisternas, José Raul; Valenti, Vitor E; Sato, Monica A; Fonseca, Fernando L A; Saldiva, Paulo H N; De Mello Monteiro, Carlos B; Neto, Modesto Leite Rolim; Rodrigues, Luciano M R; De Abreu, Luiz Carlos

    2011-12-01

    Many studies have investigated the role of oxidative stress on cardiovascular system in the brainstem of spontaneously hypertensive rats (SHR). However, we do not know yet if catalase inhibition influences cardiopulmonary reflex (Bezol-Jarisch reflex). Thus, we aimed to evaluate the effects of central catalase inhibition on cardiopulmonary reflex in SHR. Males Wistar Kyoto (WKY) rats and SHR were implanted with a stainless steel guide cannula into the fourth cerebral ventricle (4th V). The femoral artery and vein were cannulated for mean arterial pressure (MAP) and heart rate (HR) measurement and drug infusion, respectively. The cardiopulmonary reflex was tested with phenylbiguanide (PBG, 8 ?g/kg, bolus, i.v.). Cardiopulmonary reflex was evaluated before and 15 minutes after 3-amino-1,2,4-triazole (ATZ, 0.01 g/100 ?L) injection into the 4th V. Vehicle treatment did not change basal MAP and HR and cardiopulmonary reflex responses in SHR and WKY rats. Central ATZ increased hypotensive (p=0.038) responses without influencing the bradycardic reflex (p=0.287) in WKY rats. In SHR, ATZ increased hypotension (p=0.0004) and bradycardic (p=0.04) responses to i.v. PBG. No changes were observed regarding basal MAP and HR after ATZ injection in SHR and WKY rats. We suggest central catalase inhibition affects cardiopulmonary reflex with more intensity in SHR compared to WKY rats. PMID:22262536

  17. Cloning and characterization of the katA gene of Rhizobium meliloti encoding a hydrogen peroxide-inducible catalase.

    PubMed Central

    Hérouart, D; Sigaud, S; Moreau, S; Frendo, P; Touati, D; Puppo, A

    1996-01-01

    To investigate the involvement of bacterial catalases of the symbiotic gram-negative bacterium Rhizobium meliloti in the development of Medicago-Rhizobium functional nodules, we cloned a putative kat gene by screening a cosmid library with a catalase-specific DNA probe amplified by PCR from the R. meliloti genome. Nucleotide sequence analysis of a 1.8-kb DNA fragment revealed an open reading frame, called katA, encoding a peptide of 562 amino acid residues with a calculated molecular mass of 62.9 kDa. The predicted amino acid sequence showed a high homology with the primary structure of monofunctional catalases from eucaryotes and procaryotes. The katA gene was localized on the chromosome, and the katA gene product was essentially found in the periplasmic space. A katA::Tn5 mutant was obtained and showed a drastic sensitivity to hydrogen peroxide, indicating an essential protective role of KatA. However, neither Nod nor Fix phenotypes were impaired in the mutant, suggesting that KatA is not essential for nodulation and establishment of nitrogen fixation. Exposure to a sublethal concentration of H2O2 enhanced KatA activity (100-fold) and also increased survival to subsequent H2O2 exposure at higher concentrations. No protection is observed in katA::Tn5, indicating that KatA is the major component of an adaptive response. PMID:8955300

  18. Genes Up-Regulated in Tolerant Cavendish Banana Roots in Response to Fusarium oxysporum f. sp. cubense Infection1

    E-print Network

    Programme, Scottish Crop Research Institute, Invergowrie, Dundee, DD2 5DA, UK Keywords: catalase, defence-associated genes (catalase 2, pectin acetyl esterase (PAE), PR-1 and PR-3) were selected for expression profile, xylanase inhibitor, peroxidase, catalase 2, metallothionein, response regulator 6 and tripsin inhibitor

  19. Modification of catalase and MAPK in Vicia faba cultivated in soil with high natural radioactivity and treated with a static magnetic field.

    PubMed

    Haghighat, Nazanin; Abdolmaleki, Parviz; Ghanati, Faezeh; Behmanesh, Mehrdad; Payez, Atefeh

    2014-03-01

    The effects of a static magnetic field (SMF) and high natural radioactivity (HR) on catalase and MAPK genes in Vicia faba were investigated. Soil samples with high natural radioactivity were collected from Ramsar in north Iran where the annual radiation absorbed dose from background radiation is higher than 20mSv/year. The specific activity of the radionuclides of (232)Th, (236)Ra, and (40)K was measured using gamma spectrometry. The seeds were planted either in the soil with high natural radioactivity or in the control soils and were then exposed to a SMF of 30mT for 8 days; 8h/day. Levels of expression of catalase and MAPK genes, catalase activity and H2O2 content were evaluated. The results demonstrated significant differences in the expression of catalase and MAPK genes in SMF- and HR-treated plants compared to the controls. An increase in catalase activity was accompanied by increased expression of its gene and accumulation of H2O2. Relative expression of the MAPK gene in treated plants, however, was lower than those of the controls. The results suggest that the response of V. faba plants to SMF and HR may be mediated by modification of catalase and MAPK. PMID:24484963

  20. Prognostic significance of catalase expression and its regulatory effects on hepatitis B virus X protein (HBx) in HBV-related advanced hepatocellular carcinomas

    PubMed Central

    Cho, Mi-Young; Cheong, Jae Youn; Lim, Wonchung; Jo, Sujin; Lee, Youngsoo; Wang, Hee-Jung; Han, Kyou-Hoon; Cho, Hyeseong

    2014-01-01

    Hepatitis B virus X protein (HBx) plays a role in liver cancer development. We previously showed that ROS increased HBx levels and here, we investigated the role of antioxidants in the regulation of HBx expression and their clinical relevance. We found that overexpression of catalase induced a significant loss in HBx levels. The cysteine null mutant of HBx (Cys?) showed a dramatic reduction in its protein stability. In clonogenic proliferation assays, Huh7-X cells produced a significant number of colonies whereas Huh7-Cys? cells failed to generate them. The Cys at position 69 of HBx was crucial to maintain its protein stability and transactivation function in response to ROS. Among 50 HBV-related hepatocellular carcinoma (HCC) specimens, 72% of HCCs showed lower catalase levels than those of surrounding non-tumor tissues. In advanced stage IV, catalase levels in non-tumor tissues were increased whereas those in tumors were further reduced. Accordingly, patients with a high T/N ratio for catalase showed significantly longer survival than those with a low T/N ratio. Together, catalase expression in HCC patients can be clinically useful for prediction of patient survival, and restoration of catalase expression in HCCs could be an important strategy for intervention in HBV-induced liver diseases. PMID:25361011

  1. Theoretical study of model compound I complexes of horseradish peroxidase and catalase.

    PubMed Central

    Du, P; Loew, G H

    1995-01-01

    Theoretical studies of the electronic structure and spectra of models for the ferric resting state and Compound I intermediates of horseradish peroxidase (HRP-I) and catalase (CAT-I) have been performed using the INDO-RHF/CI method. The goals of these studies were twofold: i) to determine whether the axial ligand of HRP is best described as imidazole or imidazolate, and ii) to address the long-standing question of whether HRP-I and CAT-I are a1u and a2u tau cation radicals. Only the imidazolate HRP-I model led to a calculated electronic spectra consistent with the experimentally observed significant reduction in the intensity of the Soret band compared with the ferric resting state. These results provide compelling evidence for significant proton transfer to the conserved Asp residue by the proximal histidine. The origin of the observed reduction of the Soret band intensity in HRP-I and CAT-I spectra has been examined and found to be caused by the mixing of charge transfer transitions into the predominantly porphyrin tau-tau transitions. For both HRP-I and CAT-I, the a1u porphyrin tau cation state is the lowest energy, and it is further stabilized by both the anionic form of the ligand and the porphyrin ring substituents of protoporphyrin-IX. The calculated values of quadrupole-splitting observed in the Mossbauer resonance of HRP-I and CAT-I are similar for the a1u and a2u tau cation radicals. Electronic spectrum of the a1u tau cation radical of HRP-I are more similar to the observed spectra, whereas the spectra of both a1u tau and a2u tau cation radicals of CAT-I resemble the observed spectra. These results also indicate the limitations of using any one observable property to try to distinguish between these states. Taken together, comparison of calculated and observed properties indicate that there is no compelling reason to invoke the higher energy a2u tau cation radical as the favored state in HRP-I and CAT-I. Both ground-state properties and electronic spectra are consistent with the a1u tau cation radical. PMID:7711270

  2. Circadian (about 24-hour) variation in malondialdehyde content and catalase activity of mouse erythrocytes.

    PubMed

    Sani, Mamane; Sebai, Hichem; Ghanem-Boughanmi, Néziha; Boughattas, Naceur A; Ben-Attia, Mossadok

    2015-01-01

    Lipid peroxidation is a part of normal metabolism that may cause biological molecule damage leading to the formation of several specific metabolites that include aldehydes of variable chains, such as malondialdehyde (MDA). These biological effects are controlled in vivo by a wide spectrum of enzymatic and non-enzymatic defense mechanisms among which catalase (CAT) is considered as an important regulator of oxidative stress. The present study aimed to investigate the possible relationship between the temporal patterns of the formation of MDA and the activity of CAT in the erythrocytes of mice. Twenty-four-hour studies were performed on male Swiss albino mice, 12 weeks old, synchronized to a 12:12 light: dark cycle for 3 weeks. Different and comparable groups of animals (n = 10) were sacrificed at an interval of 4 hours (1, 5, 9, 13, 17, and 21 hours after light onset (HALO)). The levels of erythrocyte MDA concentration and CAT activity both significantly (analysis of variance: F = 6.4, P < 0.002) varied according to the time of sampling under non-stressed conditions. The characteristics of the waveform describing the temporal patterns differed between the two studied variables, e.g. MDA content showing one peak (?21 HALO) and CAT activity showing three peaks (?9, 17, and 21 HALO). Cosinor analysis revealed a significant (adjusted Cosinor: P ? 0.018) circadian (? ? 24 hours) rhythm in MDA level and no statistically significant rhythmicity in CAT activity. The differences and the absence of correlation between the curve patterns of erythrocyte MDA content and CAT activity under physiological conditions are hypothesized to explain that variation in lipid peroxidation may depend on several factors. Moreover, the identification of peak/trough levels of MDA accumulation in erythrocytes may reflect the degree of oxidative stress in these blood cells. In addition, the observed significant time-of-day effect suggests that, in both clinical and scientific settings, appropriate comparison of MDA production and CAT activity levels can only be achieved on data obtained at the same time of day. PMID:25142617

  3. beta-D(+) glucose-glucose oxidase-catalase for use as an antioxidant system.

    PubMed

    Uppoor, R; Niebergall, P J

    1996-07-01

    The purpose of this study was to investigate the use of beta-D(+) glucose-glucose oxidase (EC 1.1.3.4)-catalase (EC 1.11.1.6) (BDG-GO-CAT) as a new antioxidant system in solutions. A novel method for estimation of activity of the system was developed using a dissolved oxygen (DO) meter and an oxygen probe. The method can be used to determine the enzymatic activity of the system at GO concentrations of 0.005 to 0.030 unit/ml, with an r2 of 0.995 for the linearity of the standard curve, and can be adapted for analysis in any solution. At room temperature of 23.0 degrees +/- 2.0 degrees C, the maximum activity of the BDG-GO-CAT system was found to occur at pH 5.40. The half-life values for the stability of GO-CAT in 0.10 M phosphate buffer solutions of pH 4.0, 5.0, 6.0, 7.0, 8.0, 9.0, and 10.0 were 9.78, 49.43, 53.46, 36.51, 12.68, 1.84, and 0.80 weeks, respectively. Dextrose was used in place of beta-D(+) glucose for cost-saving purposes, and a standard curve for the activity of GO-CAT was obtained using 20 mg/ml dextrose. The BDG-GO-CAT was effective as a DO-scavenger in closed containers, when the containers were opened and exposed to atmosphere for 2 days between tests, and upon reclosing them. Pharmaceutical excipients such as ethanol, glycerin, propylene glycol, methylparaben, propylparaben, artificial strawberry flavor, and sodium benzoate did not show any adverse effect on the activity of BDG-GO-CAT. Sorbitol, high-fructose corn syrup, sucrose, and polyethylene glycol 3350 increased the rate of DO removal. Sodium carboxymethyl-cellulose (CMC) at 2.0% w/v decreased the rate of DO removal. These studies indicate that the BDG(dextrose)-GO-CAT system warrants serious consideration for use an antioxidant system in aqueous formulations. PMID:9552339

  4. Antioxidant pathways are up-regulated during biological nitrogen fixation to prevent ROS-induced nitrogenase inhibition in Gluconacetobacter diazotrophicus.

    PubMed

    Alquéres, Sylvia M C; Oliveira, Jose Henrique M; Nogueira, Eduardo M; Guedes, Helma V; Oliveira, Pedro L; Câmara, Fernando; Baldani, Jose I; Martins, Orlando B

    2010-10-01

    Gluconacetobacter diazotrophicus, an endophyte isolated from sugarcane, is a strict aerobe that fixates N(2). This process is catalyzed by nitrogenase and requires copious amounts of ATP. Nitrogenase activity is extremely sensitive to inhibition by oxygen and reactive oxygen species (ROS). However, the elevated oxidative metabolic rates required to sustain biological nitrogen fixation (BNF) may favor an increased production of ROS. Here, we explored this paradox and observed that ROS levels are, in fact, decreased in nitrogen-fixing cells due to the up-regulation of transcript levels of six ROS-detoxifying genes. A cluster analyses based on common expression patterns revealed the existence of a stable cluster with 99.8% similarity made up of the genes encoding the ?-subunit of nitrogenase Mo-Fe protein (nifD), superoxide dismutase (sodA) and catalase type E (katE). Finally, nitrogenase activity was inhibited in a dose-dependent manner by paraquat, a redox cycler that increases cellular ROS levels. Our data revealed that ROS can strongly inhibit nitrogenase activity, and G. diazotrophicus alters its redox metabolism during BNF by increasing antioxidant transcript levels resulting in a lower ROS generation. We suggest that careful controlled ROS production during this critical phase is an adaptive mechanism to allow nitrogen fixation. PMID:20697694

  5. Up-Regulated Expression of AOS-LOXa and Increased Eicosanoid Synthesis in Response to Coral Wounding

    PubMed Central

    Lõhelaid, Helike; Teder, Tarvi; Tõldsepp, Kadri; Ekins, Merrick; Samel, Nigulas

    2014-01-01

    In octocorals, a catalase–like allene oxide synthase (AOS) and an 8R-lipoxygenase (LOX) gene are fused together encoding for a single AOS-LOX fusion protein. Although the AOS-LOX pathway is central to the arachidonate metabolism in corals, its biological function in coral homeostasis is unclear. Using an acute incision wound model in the soft coral Capnella imbricata, we here test whether LOX pathway, similar to its role in plants, can contribute to the coral damage response and regeneration. Analysis of metabolites formed from exogenous arachidonate before and after fixed time intervals following wounding indicated a significant increase in AOS-LOX activity in response to mechanical injury. Two AOS-LOX isoforms, AOS-LOXa and AOS-LOXb, were cloned and expressed in bacterial expression system as active fusion proteins. Transcription levels of corresponding genes were measured in normal and stressed coral by qPCR. After wounding, AOS-LOXa was markedly up-regulated in both, the tissue adjacent to the incision and distal parts of a coral colony (with the maximum reached at 1 h and 6 h post wounding, respectively), while AOS-LOXb was stable. According to mRNA expression analysis, combined with detection of eicosanoid product formation for the first time, the AOS-LOX was identified as an early stress response gene which is induced by mechanical injury in coral. PMID:24551239

  6. Fusicoccin-induced catalase inhibitor is produced independently of H+-ATPase activation and behaves as an organic acid.

    PubMed

    Beffagna, Nicoletta; Riva, Marzia Alessandra

    2011-06-01

    The phytotoxin fusicoccin (FC) was found to induce an increase in apoplastic H?O? content in Arabidopsis thaliana cells, apparently linked to the presence of an as yet unidentified catalase inhibitor detectable even in the external medium of FC-treated cells. This study, aimed to further characterize the inhibitor's features, shows that (1) FC-induced H?O? accumulation increases as a function of FC concentration and correlates to the amount of inhibitor released at apoplastic level. The pattern of H+ efflux, conversely, does not fit with that of these two parameters, suggesting that neither the production nor the release of the catalase inhibitor is linked to the main role of FC in activating the plasma membrane (PM) H+-ATPase; (2) treatment with 10 µM erythrosine B (EB) early and totally inhibits net H+ and K+ fluxes across the PM, indicative of the H+ pump activity; nevertheless, also in these conditions a huge FC-induced H?O? accumulation occurs, confirming that this effect is not related to the FC-induced PM H+-ATPase activation; (3) the inhibitor's release increases with time in all conditions tested and is markedly affected by extracellular pH (a higher pH value being associated to a larger efflux), in agreement with a weak acid release; and (4) the inhibitor can be almost completely recovered in a CH?C?-soluble fraction extracted from the incubation medium by sequential acid-base partitioning which contains nearly all of the organic acids released. These final results strongly suggest that the metabolite responsible for the FC-induced catalase inhibition belongs to the organic acid class. PMID:21320127

  7. Effects of N-acetyl-l-cysteine and catalase on the viability and motility of chicken sperm during liquid storage.

    PubMed

    Partyka, Agnieszka; Ni?a?ski, Wojciech; Bratkowska, Martyna; Ma?likowski, Piotr

    2015-06-01

    The purpose of the current study was to investigate the effects of N-acetyl-l-cysteine (NAC) and catalase (CAT) on chicken sperm parameters during liquid storage for up to 48h at 5°C. Supplementation of EK extender with NAC (15mM) increased sperm motility after 24h. After 48h, an increase in sperm viability with NAC (5, 15mM) and CAT (100, 300U/mL) was observed, but only treatment with 15mM NAC improved sperm progressive motility. PMID:26051462

  8. Oxidative stress to DNA, protein, and antioxidant enzymes (superoxide dismutase and catalase) in rats treated with benzo( a)pyrene

    Microsoft Academic Search

    Kyu Bong Kim; Byung Mu Lee

    1997-01-01

    Oxidative DNA damage (as 8-hydroxydeoxyguanosine; 8-OHdG), carbonyl content of proteins, and activities of superoxide dismutase (SOD) and catalase were investigated in female Sprague-Dawley rats orally treated with benzo(a)pyrene (B(a)P) (75 mg\\/rat). HPLC-ECD system showed that B(a)P increased the level of 8-OHdG in tissues (liver, kidney, and lung), but a statistical significance was observed only in the liver (3.5-fold increase) and

  9. Endogenous allergen upregulation: transgenic vs. traditionally bred crops.

    PubMed

    Herman, Rod A; Ladics, Gregory S

    2011-10-01

    The safety assessment for transgenic food crops currently includes an evaluation of the endogenous allergy potential (via serum IgE screening) when the non-transgenic counterpart is a commonly allergenic food. The value of this analysis in the safety assessment of transgenic crops, especially with reference to recent requests to quantify individual allergen concentrations in raw commodities, is examined. We conclude that the likelihood of upregulating an endogenous allergen due to transgenesis is no greater than from traditional breeding which has a history of safety and is largely unregulated. The potential consequences of upregulating an endogenous allergen are also unclear. PMID:21784119

  10. The effect of some factors of polluted environment on catalase responses and resistance of microbial isolates against toxic oxidative stress.

    PubMed

    Polek, Bystrík; Godo?íková, Jana

    2012-10-01

    The properties of bacterial isolates from polluted environments which are characterized by increased levels of oxidative stress do not reflect only the level of contaminants, but also arise as a consequence of many permanently changed conditions. The survival rate of Comamonas terrigena N3H isolates from an environment with elevated levels of H(2)O(2) is correlated with stimulation of catalase. The response of bacterial catalase to the effect of phenol in exogenous conditions was affected by the presence of an additional contaminant, Cd(2+). An isolate of Aspergillus niger selected from river sediment containing 363 mg/kg As, 93 mg/kg Sb at pH 5.2-4.8 grew on Czapek-Dox agar ~1.6 times faster than an isolate of the same species from coal dust sediment with approximately the same level of pollution (400 mg/kg As) but somewhat lower pH (3.3-2.8). It also exhibited differences in the microscopic characteristics of its mycelial structures. Both isolates exhibited a higher tolerance to the exogenic toxic effects of metals (As(5+), Cd(2+), and Cu(2+) at 5, 25, or 50 mg/L) than a control culture, but the differences in tolerance between them were only slight. These laboratory results suggest that there are complicated relationships which may exist in the "in situ" environment. PMID:22706798

  11. Immunocytochemical localization of urate oxidase, fatty acyl-CoA oxidase, and catalase in bovine kidney peroxisomes.

    PubMed

    Usuda, N; Usman, M I; Reddy, M K; Hashimoto, T; Reddy, J K; Rao, M S

    1988-03-01

    We investigated the localization of urate oxidase, peroxisomal fatty acyl-CoA oxidase, and catalase in bovine kidney by immunoblot analysis and protein A-gold immunocytochemistry, using the respective polyclonal monospecific antibodies raised against the enzymes purified from rat liver. By immunoblot analysis, these three proteins were detected in bovine kidney and bovine liver homogenates. Subcellular localization of these three enzymes in kidney was ascertained by protein A-gold immunocytochemical staining of Lowicryl K4M-embedded tissue. Peroxisomes in bovine kidney cortical epithelium possessed crystalloid cores or nucleoids, which were found to be the exclusive sites of urate oxidase localization. The limiting membrane, the marginal plate, and the matrix of renal peroxisomes were negative for urate oxidase staining. In contrast, catalase and fatty acyl-CoA oxidase were found in the peroxisome matrix. These results demonstrate that, unlike rat kidney peroxisomes which lack urate oxidase, peroxisomes of bovine kidney contain this enzyme as well as peroxisomal fatty acyl-CoA oxidase. PMID:3343509

  12. A genetic approach to study H2O2 scavenging in fission yeast--distinct roles of peroxiredoxin and catalase.

    PubMed

    Paulo, Esther; García-Santamarina, Sarela; Calvo, Isabel A; Carmona, Mercè; Boronat, Susanna; Domènech, Alba; Ayté, José; Hidalgo, Elena

    2014-04-01

    The main peroxiredoxin in Schizosaccharomyces pombe, Tpx1, is important to sustain aerobic growth, and cells lacking this protein are only able to grow on solid plates under anaerobic conditions. We have found that deletion of the gene coding for thioredoxin reductase, trr1, is a suppressor of the sensitivity to aerobic growth of ?tpx1 cells, so that cells lacking both proteins are able to grow on solid plates in the presence of oxygen. We have investigated this suppression effect, and determined that it depends on the presence of catalase, which is constitutively expressed in ?trr1 cells in a transcription factor Pap1-dependent manner. A complete characterization of the repertoire of hydrogen peroxide scavenging activities in fission yeast suggests that Tpx1 is the only enzyme with sufficient sensitivity for peroxides and cellular abundance as to control the low levels produced during aerobic growth, catalase being the next barrier of detoxification when the steady-state levels of peroxides are increased in ?tpx1 cells. Gpx1, the only glutathione peroxidase encoded by the S.?pombe genome, only has a minor secondary role when extracellular peroxides are added. Our study proposes non-overlapping roles for the different hydrogen peroxide scavenging activities of this eukaryotic organism. PMID:24521463

  13. Genes Upregulated in Human Fetal by Infection or Labor

    E-print Network

    Bryant-Greenwood, Gillian D.

    by The American College of Obstetricians and Gynecologists.) Preterm birth is a multifactorial disease, and itsGenes Upregulated in Human Fetal by Infection or Labor Membranes LILY S. TASHIMA, PhD, LYNNAE K. MILLAR, MD, AND GILLIAN D. BRYANT-GREENWOOD, PhD Objective: To determine whether suppression subtractive

  14. Cyclooxygenase-2 is Upregulated in Copper-Deficient Rats

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Copper deficiency inactivates Cu/Zn-SOD and promotes accumulation of reactive oxygen species. This process likely impairs nitric oxide (NO)-mediated relaxation as well as triggers vascular inflammation. The current study was designed to determine whether COX-2 expression and activity are upregulated...

  15. ORIGINAL ARTICLE Upregulation of RASGRP3 expression in prostate cancer

    E-print Network

    Cai, Long

    OPEN ORIGINAL ARTICLE Upregulation of RASGRP3 expression in prostate cancer correlates and tissues in BPH and prostate cancer (PCa), as well as its associations with cancer invasion and prognosis Cancer and Prostatic Disease (2014) 17, 119­125; doi:10.1038/pcan.2013.51; published online 14 January

  16. Up-Regulated Dicer Expression in Patients with Cutaneous Melanoma

    E-print Network

    Oliver, Douglas L.

    Up-Regulated Dicer Expression in Patients with Cutaneous Melanoma Zhihai Ma1 , Helen Swede2 , David clinically annotated controls and skin tumors consisting of melanocytic nevi (n = 71), a variety of melanomas Dicer in 81% of cutaneous, 80% of acrolentiginous and 96% of metastatic melanoma specimens compared

  17. JOURNAL DE PHYSIQUE Colloque C2, supplPmen2 au no 3, Tome 40, mars 1979, page C2-528 THE ACT1VE CENTER OF BACTERlAL CATALASE INVEST1GATED BY MOSSBAUER SPECTROSCOPY

    E-print Network

    Paris-Sud XI, Université de

    CENTER OF BACTERlAL CATALASE INVEST1GATED BY MOSSBAUER SPECTROSCOPY F. Parak, D. Bade and A.L. Yarie Max.- La catalase de Micrococcus luteus enrichie au 5 7 ~ ea Qtb etudibe en u t i l i s a n t l a spectros l o r s de mesures EPR. Les quatre sous-unitbs de l a catalase prbsentent un comportement identique

  18. Extraction of superoxide dismutase, catalase, and carbonic anhydrase from stroma-free red blood cell hemolysate for the preparation of the nanobiotechnological complex of polyhemoglobin-superoxide dismutase-catalase-carbonic anhydrase.

    PubMed

    Guo, C; Gynn, M; Chang, T M S

    2015-06-01

    We report a novel method to simultaneously extract superoxide dismutase (SOD), catalase (CAT), and carbonic anhydrase (CA) from the same sample of red blood cells (RBCs). This avoids the need to use expensive commercial enzymes, thus enabling a cost-effective process for large-scale production of a nanobiotechnological polyHb-SOD-CAT-CA complex, with enhancement of all three red blood cell functions. An optimal concentration of phosphate buffer for ethanol-chloroform treatment results in good recovery of CAT, SOD, and CA after extraction. Different concentrations of the enzymes can be used to enhance the activity of polyHb-SOD-CAT-CA to 2, 4, or 6 times that of RBC. PMID:25961364

  19. Spectroscopic and kinetic investigation of the reactions of peroxyacetic acid with Burkholderia pseudomallei catalase-peroxidase, KatG.

    PubMed

    Ivancich, Anabella; Donald, Lynda J; Villanueva, Jacylyn; Wiseman, Ben; Fita, Ignacio; Loewen, Peter C

    2013-10-15

    Catalase-peroxidases or KatGs can utilize organic peroxyacids and peroxides instead of hydrogen peroxide to generate the high-valent ferryl-oxo intermediates involved in the catalase and peroxidase reactions. In the absence of peroxidatic one-electron donors, the ferryl intermediates generated with a low excess (10-fold) of peroxyacetic acid (PAA) slowly decay to the ferric resting state after several minutes, a reaction that is demonstrated in this work by both stopped-flow UV-vis absorption measurements and EPR spectroscopic characterization of Burkholderia pseudomallei KatG (BpKatG). EPR spectroscopy showed that the [Fe(IV)?O Trp330(•+)], [Fe(IV)?O Trp139(•)], and [Fe(IV)?O Trp153(•)] intermediates of the peroxidase-like cycle of BpKatG ( Colin, J. Wiseman, B. Switala, J. Loewen, P. C. Ivancich, A. ( 2009 ) J. Am. Chem. Soc. 131 , 8557 - 8563 ), formed with a low excess of PAA at low temperature, are also generated with a high excess (1000-fold) of PAA at room temperature. However, under high excess conditions, there is a rapid conversion to a persistent [Fe(IV)?O] intermediate. Analysis of tryptic peptides of BpKatG by mass spectrometry before and after treatment with PAA showed that specific tryptophan (including W330, W139, and W153), methionine (including Met264 of the M-Y-W adduct), and cysteine residues are either modified with one, two, or three oxygen atoms or could not be identified in the spectrum because of other undetermined modifications. It was concluded that these oxidized residues were the source of electrons used to reduce the excess of PAA to acetic acid and return the enzyme to the ferric state. Treatment of BpKatG with PAA also caused a loss of catalase activity towards certain substrates, consistent with oxidative disruption of the M-Y-W adduct, and a loss of peroxidase activity, consistent with accumulation of the [Fe(IV)?O] intermediate and the oxidative modification of the W330, W139, and W153. PAA, but not H2O2 or tert-butyl hydroperoxide, also caused subunit cross-linking. PMID:24044787

  20. Piper betle shows antioxidant activities, inhibits MCF-7 cell proliferation and increases activities of catalase and superoxide dismutase

    PubMed Central

    2012-01-01

    Background Breast cancer is the most common form of cancer and the focus on finding chemotherapeutic agents have recently shifted to natural products. Piper betle is a medicinal plant with various biological activities. However, not much data is available on the anti-cancer effects of P. betle on breast cancer. Due to the current interest in the potential effects of antioxidants from natural products in breast cancer treatment, we investigated the antioxidant activities of the leaves of P. betle and its inhibitory effect on the proliferation of the breast cancer cell line, MCF-7. Methods The leaves of P. betle were extracted with solvents of varying polarities (water, methanol, ethyl acetate and hexane) and their phenolic and flavonoid content were determined using colorimetric assays. Phenolic composition was characterized using HPLC. Antioxidant activities were measured using FRAP, DPPH, superoxide anion, nitric oxide and hyroxyl radical scavenging assays. Biological activities of the extracts were analysed using MTT assay and antioxidant enzyme (catalase, superoxide dismutase, glutathione peroxidase) assays in MCF-7 cells. Results Overall, the ethyl acetate extract showed the highest ferric reducing activity and radical scavenging activities against DPPH, superoxide anion and nitric oxide radicals. This extract also contained the highest phenolic content implying the potential contribution of phenolics towards the antioxidant activities. HPLC analyses revealed the presence of catechin, morin and quercetin in the leaves. The ethyl acetate extract also showed the highest inhibitory effect against the proliferation of MCF-7 cells (IC50=65 ?g/ml). Treatment of MCF-7 cells with the plant extract increased activities of catalase and superoxide dismutase. Conclusions Ethyl acetate is the optimal solvent for the extraction of compounds with antioxidant and anti-proliferative activities. The increased activities of catalase and superoxide dismutase in the treated cells could alter the antioxidant defense system, potentially contributing towards the anti-proliferative effect. There is great potential for the ethyl acetate extract of P. betle leaf as a source of natural antioxidants and to be developed as therapeutics in cancer treatment. PMID:23153283

  1. The in Vivo and in Vitro Inhibition of Catalase from Leaves of Nicotiana sylvestris by 3-Amino-1,2,4-Triazole.

    PubMed

    Havir, E A

    1992-06-01

    Seedlings of tobacco (Nicotiana sylvestris) were treated in vivo with 0.03 to 20 millimolar 3-amino-1,2,4-triazole (aminotriazole). There was a rapid loss of catalase (EC 1.11.1.6) activity over the first 5 hours followed by a slower decrease for the next 4 hours to a level that was 15 to 20% of the initial activity, with little or no change for periods up to 3 days. Fifty percent loss of catalase activity occurred at 0.10 to 0.15 millimolar inhibitor (18-hour incubation). The isozymes of tobacco catalase differed in sensitivity to the inhibitor. Enhanced-peroxidatic catalase (EP-CAT) (Havir EA, McHale NA, [1989] Plant Physiol 91: 812-815) decreased 35% under conditions in which the major isozyme decreased 85%. The resistance to aminotriazole inhibition demonstrated in vivo by EP-CAT was also observed in vitro. The times for 50% inhibition at 0.67, 3.33, 5.0, 10.0, and 15 millimolar aminotriazole were 15, 5, 2.6, 2.5, and 1.5 minutes, respectively, for the major isozyme of catalase and 60, 18.5, 5.1, 4, and 3.0 minutes, respectively, for EP-CAT. Increasing H(2)O(2) concentration did not change the sensitivity of EP-CAT to aminotriazole. The major form of catalase contained 4.0 +/- 0.4 moles of heme per mole enzyme and EP-CAT 3.4 +/- 0.3. Thus, the resistance of EP-CAT to aminotriazole is probably not due to lowered affinity for H(2)O(2) or alteration in heme content but to structural changes that impair inhibitor binding. PMID:16668919

  2. Direct and indirect inactivation of tumor cell protective catalase by salicylic acid and anthocyanidins reactivates intercellular ROS signaling and allows for synergistic effects.

    PubMed

    Scheit, Katrin; Bauer, Georg

    2015-03-01

    Salicylic acid and anthocyanidins are known as plant-derived antioxidants, but also can provoke paradoxically seeming prooxidant effects in vitro. These prooxidant effects are connected to the potential of salicylic acid and anthocyanidins to induce apoptosis selectively in tumor cells in vitro and to inhibit tumor growth in animal models. Several epidemiological studies have shown that salicylic acid and its prodrug acetylsalicylic acid are tumor-preventive for humans. The mechanism of salicylic acid- and anthocyanidin-dependent antitumor effects has remained enigmatic so far. Extracellular apoptosis-inducing reactive oxygen species signaling through the NO/peroxynitrite and the HOCl signaling pathway specifically induces apoptosis in transformed cells. Tumor cells have acquired resistance against intercellular reactive oxygen species signaling through expression of membrane-associated catalase. Here, we show that salicylic acid and anthocyanidins inactivate tumor cell protective catalase and thus reactive apoptosis-inducing intercellular reactive oxygen species signaling of tumor cells and the mitochondrial pathway of apoptosis Salicylic acid inhibits catalase directly through its potential to transform compound I of catalase into the inactive compound II. In contrast, anthocyanidins provoke a complex mechanism for catalase inactivation that is initiated by anthocyanidin-mediated inhibition of NO dioxygenase. This allows the formation of extracellular singlet oxygen through the reaction between H(2)O(2) and peroxynitrite, amplification through a caspase8-dependent step and subsequent singlet oxygen-mediated inactivation of catalase. The combination of salicylic acid and anthocyanidins allows for a remarkable synergistic effect in apoptosis induction. This effect may be potentially useful to elaborate novel therapeutic approaches and crucial for the interpretation of epidemiological results related to the antitumor effects of secondary plant compounds. PMID:25653236

  3. Effect of dioxydine and cyclophosphane on lipid peroxidation and superoxide dismutase and catalase activities in C57Bl\\/6 and BALB\\/c mice

    Microsoft Academic Search

    A. D. Durnev; T. G. Sazontova; N. V. Guseva; S. B. Seredenin

    1996-01-01

    Twenty-four hours after intraperitoneal injection of cyclophosphane (40 mg\\/kg) and dioxydine (300 mg\\/kg) to C57Bl\\/6 mice,\\u000a liver catalase activity dropped by 29 and 23%, respectively. In BALB\\/c mice, dioxydine (but not cyclophosphane) reduced catalase\\u000a activity by 24%. Superoxide dismutase activity was lowered by cyclophosphane (but not dioxydine) in BALB\\/c mice, and by both\\u000a dioxydine and cyclophosphane in C57Bl\\/6 mice (by

  4. [Effect of lipolytic and catalase activity on physico-mechanical properties of coating Polyken 980-25].

    PubMed

    Kopteva, Zh P; Zanina, V V; Boretskaia, M A; Kopteva, A E; Kozlova, I A

    2013-01-01

    Lipolytic and catalase activity of Pseudomonas pseudoalcaligenes 109, Rhodococcus erythropolis 102, Bacillus subtilis 138 and their association with different growth models: biofilm and plankton ones. It is shown that under biofilm conditions the fermentative activity of bacteria under study was 1.5-1.7 times higher than under plankton conditions. Monocultures of bacteria displayed much lower activity than associative ones. Changes of physico-chemical properties of the specimens of protective coating Polyken 980-25 with participation of the above bacteria have been studied. The coating breaking strength decreases by 5.9-11.8% under the effect of monocultures, and by 17.3% under the effect of association. The adhesive strength as the basic index of coating biologic resistance decreased, respectively, in mono- and associated cultures by 28.6-73.2% in respect of the control. Damaging the sticking layer of isolation coating, bacteria damage the adhesion to metal which favors its corrosion. PMID:23516839

  5. Oversynthesis of riboflavin in the yeast Pichia guilliermondii is accompanied by reduced catalase and superoxide dismutases activities.

    PubMed

    Prokopiv, Tetyana M; Fedorovych, Dariya V; Boretsky, Yuriy R; Sibirny, Andriy A

    2013-01-01

    Iron deficiency causes oversynthesis of riboflavin in several yeast species, known as flavinogenic yeasts. Under iron deprivation conditions, Pichia guilliermondii cells increase production of riboflavin and malondialdehyde and the formation of protein carbonyl groups, which reflect increased intracellular content of reactive oxygen species. In this study, we found that P. guilliermondii iron deprived cells showed dramatically decreased catalase and superoxide dismutase activities. Previously reported mutations rib80, rib81, and hit1, which affect repression of riboflavin synthesis and iron accumulation by iron ions, caused similar drops in activities of the mentioned enzymes. These findings could explain the previously described development of oxidative stress in iron deprived or mutated P. guilliermondii cells that overproduce riboflavin. Similar decrease in superoxide dismutase activities was observed in iron deprived cells in the non-flavinogenic yeast Saccharomyces cerevisiae. PMID:23053489

  6. [Qualitative composition of carotenoids, catalase and superoxide dismutase activities in tissues of bivalve mollusc Anadara inaequivalvis (Bruguiere, 1789)].

    PubMed

    Soldatov, A A; Gostiukhina, O L; Borodina, A V; Golovina, I V

    2013-01-01

    By using high-performance liquid chromatography, UV-VIS-spectra and mass spectra (FAB MS) in tissues of bivalve mollusc Anadara inaequivalvis (Bruguiere, 1789) there are identified seven kinds of carotenoids: trans- and cis-pectenolon, alloxanthin, pectenol A, beta-carotene, zeaxanthin, and diatoxanthin. Their quantitative ratio in hepatopancreas, gills, and foot of the animals was determined. There was revealed negative correlation (R2 about 0.9) between content of several carotenoids (trans- and cis-pectenolon, zeaxanthin, alloxanthin, and diatoxanthin) in tissues and activities of antioxidant enzymes (catalase and superoxide dismutase). The presence of competitive relations between these molecular systems is assumed and their underlying causes are discussed. PMID:24459858

  7. Polymer-Induced Heteronucleation for Protein Single Crystal Growth: Structural Elucidation of Bovine Liver Catalase and Concanavalin A Forms

    SciTech Connect

    Foroughi, Leila M.; Kang, You-Na; Matzger, Adam J. (Michigan)

    2012-05-09

    Obtaining single crystals for X-ray diffraction remains a major bottleneck in structural biology; when existing crystal growth methods fail to yield suitable crystals, often the target rather than the crystallization approach is reconsidered. Here we demonstrate that polymer-induced heteronucleation, a powerful technique that has been used for small molecule crystallization form discovery, can be applied to protein crystallization by optimizing the heteronucleant composition and crystallization formats for crystallizing a wide range of protein targets. Applying these advances to two benchmark proteins resulted in dramatically increased crystal size, enabling structure determination, for a half century old form of bovine liver catalase (BLC) that had previously only been characterized by electron microscopy, and the discovery of two new forms of concanavalin A (conA) from the Jack bean and accompanying structural elucidation of one of these forms.

  8. Mycobacterial catalase–peroxidase is a tissue antigen and target of the adaptive immune response in systemic sarcoidosis

    PubMed Central

    Song, Zhimin; Marzilli, Lisa; Greenlee, Brian M.; Chen, Edward S.; Silver, Richard F.; Askin, Frederic B.; Teirstein, Alvin S.; Zhang, Ying; Cotter, Robert J.; Moller, David R.

    2005-01-01

    Sarcoidosis is a disease of unknown etiology characterized by noncaseating epithelioid granulomas, oligoclonal CD4+ T cell infiltrates, and immune complex formation. To identify pathogenic antigens relevant to immune-mediated granulomatous inflammation in sarcoidosis, we used a limited proteomics approach to detect tissue antigens that were poorly soluble in neutral detergent and resistant to protease digestion, consistent with the known biochemical properties of granuloma-inducing sarcoidosis tissue extracts. Tissue antigens with these characteristics were detected with immunoglobulin (Ig)G or F(ab?)2 fragments from the sera of sarcoidosis patients in 9 of 12 (75%) sarcoidosis tissues (150–160, 80, or 60–64 kD) but only 3 of 22 (14%) control tissues (all 62–64 kD; P = 0.0006). Matrix-assisted laser desorption/ionization time of flight mass spectrometry identified Mycobacterium tuberculosis catalase–peroxidase (mKatG) as one of these tissue antigens. Protein immunoblotting using anti-mKatG monoclonal antibodies independently confirmed the presence of mKatG in 5 of 9 (55%) sarcoidosis tissues but in none of 14 control tissues (P = 0.0037). IgG antibodies to recombinant mKatG were detected in the sera of 12 of 25 (48%) sarcoidosis patients compared with 0 of 11 (0%) purified protein derivative (PPD)? (P = 0.0059) and 4 of 10 (40%) PPD+ (P = 0.7233) control subjects, suggesting that remnant mycobacterial catalase–peroxidase is one target of the adaptive immune response driving granulomatous inflammation in sarcoidosis. PMID:15753209

  9. Iron upregulates melanogenesis in cultured retinal pigment epithelial cells.

    PubMed

    Wolkow, Natalie; Li, Yafeng; Maminishkis, Arvydas; Song, Ying; Alekseev, Oleg; Iacovelli, Jared; Song, Delu; Lee, Jennifer C; Dunaief, Joshua L

    2014-11-01

    The purpose of our studies was to examine the relationship between iron and melanogenesis in retinal pigment epithelial cells, as prior observations had suggested that iron may promote melanogenesis. This relationship has potential clinical importance, as both iron overload and hyperpigmentation are associated with age-related macular degeneration (AMD). Human fetal retinal pigment epithelial cells and ARPE-19 cells were treated with iron in the form of ferric ammonium citrate, after which quantitative RT-PCR and electron microscopy were performed. Melanogenesis genes tyrosinase, tyrosinase-related protein 1, Hermansky-Pudlak Syndrome 3, premelanosome protein and dopachrome tautomerase were upregulated, as was the melanogenesis-controlling transcription factor, microphthalmia-associated transcription factor (MITF). Iron-treated cells had increased pigmentation and melanosome number. Multiple transcription factors upstream of MITF were upregulated by iron. PMID:25277027

  10. Uromodulin Upregulates TRPV5 by Impairing Caveolin-Mediated Endocytosis

    PubMed Central

    Wolf, Matthias T.F.; Wu, Xue-Ru; Huang, Chou-Long

    2013-01-01

    Uromodulin (UMOD) is synthesized in the thick ascending limb and secreted into urine as the most abundant protein. Association studies in humans suggest protective effects of UMOD against calcium-containing kidney stones. Mice carrying mutations of Umod found in human uromodulin-associated kidney disease (UAKD) and Umod deficient mice exhibit hypercalciuria. The mechanism for UMOD regulation of urinary Ca2+ excretion is incompletely understood. We examined if UMOD regulates TRPV5 and TRPV6, channels critical for renal transcellular Ca2+ reabsorption. Coexpression with UMOD increased whole-cell TRPV5 current density in HEK293 cells. In biotinylation studies UMOD increased TRPV5 cell-surface abundance. Extracellular application of purified UMOD upregulated TRPV5 current density within physiological relevant concentration ranges. UMOD exerted a similar effect on TRPV6. TRPV5 undergoes constitutive caveolin-mediated endocytosis. UMOD had no effect on TRPV5 in a caveolin-1 deficient cell line. Expression of recombinant caveolin-1 in these cells restored the ability of UMOD to upregulate TRPV5. Secretion of UAKD-mutant UMOD was markedly reduced and coexpression of mutant UMOD with TRPV5 failed to increase its current. Immunofluorescent studies demonstrated lower TRPV5 expression in Umod?/? mice compared to wild-type. UMOD upregulates TRPV5 by acting from extracellular and by decreasing endocytosis of TRPV5. The stimulation of Ca2+ reabsorption via TRPV5 by UMOD may contribute to protection against kidney stone formation. PMID:23466996

  11. Upregulation of Trop-2 quantitatively stimulates human cancer growth.

    PubMed

    Trerotola, M; Cantanelli, P; Guerra, E; Tripaldi, R; Aloisi, A L; Bonasera, V; Lattanzio, R; de Lange, R; Weidle, U H; Piantelli, M; Alberti, S

    2013-01-10

    Trop-2 is a calcium signal transducer that is associated with transformed cell growth in experimental systems. However, its role in human cancer remains essentially unknown. In this study, we profiled Trop-2 expression in normal human tissues at the mRNA and protein levels. We then systematically compared Trop-2 mRNA and protein levels in tumours with their tissues of origin. We find that Trop-2 expression is invariably upregulated in tumours, regardless of baseline expression in normal tissues, which suggests a corresponding selective advantage. Thus, we investigated the outcome of Trop-2 upregulation on tumour growth. Overexpression of wild-type Trop-2 was shown to be necessary and sufficient to drive cancer growth in a widely invariant manner across cell type and species. Upregulation of Trop-2 was shown to quantitatively stimulate tumour growth, as proportional to expression levels in vivo, and tumour cell growth was abrogated by somatic knockdown of Trop-2 expression. On the other hand, we found no evidence of tumour-associated TROP2 mutations, nor of TROP2 induction of oncogenic transformation per se. Our data support a model where above-baseline expression of wild-type Trop-2 is a key driver of human cancer growth. PMID:22349828

  12. Protandim attenuates intimal hyperplasia in human saphenous veins cultured ex vivo via a catalase-dependent pathway

    Microsoft Academic Search

    Binata Joddar; Rashmeet K. Reen; Michael S. Firstenberg; Saradhadevi Varadharaj; Joe M. McCord; Jay L. Zweier; Keith J. Gooch

    2011-01-01

    Human saphenous veins (HSVs) are widely used for bypass grafts despite their relatively low long-term patency. To evaluate the role of reactive oxygen species (ROS) signaling in intima hyperplasia (IH), an early stage pathology of vein-graft disease, and to explore the potential therapeutic effects of up-regulating endogenous antioxidant enzymes, we studied segments of HSV cultured ex vivo in an established

  13. Dormancy in grape buds: isolation and characterization of catalase cDNA and analysis of its expression following chemical induction of bud dormancy release

    Microsoft Academic Search

    Etti; Iris Vilozny; Anne Fennell; Yoram Eyal; Aliza Ogrodovitch

    2002-01-01

    The mechanism by which hydrogen cyanamide (HC) exerts its dormancy-breaking effect is not clear, but it has been shown to inactivate catalase in grape buds shortly after its application. Recently, we showed that some potential components in the process leading to dormancy release are induced at the level of gene expression following application of HC. Therefore, we inquired whether changes

  14. Copper and Zinc-containing Superoxide Dismutase, Manganese-containing Superoxide Dismutase, Catalase, and Glutathione Peroxidase in Normal and Neoplastic Human Cell Lines and Normal Human Tissues1

    Microsoft Academic Search

    Stefan L. Marklund; N. Gunnar Westman; Erik Lundgren; Goran Roos

    Copper- and zinc-containing Superoxide dismutase, man ganese-containing Superoxide dismutase, catalase, and gluta- thione peroxidase form the primary enzymic defense against toxic oxygen reduction metabolites. Such metabolites have been implicated in the damage brought about by ionizing radiation, as well as in the effects of several cytostatic com pounds. These enzymes were analyzed in 31 different human normal diploid and neoplastic

  15. Transduction of human catalase mediated by an HIV1 TAT protein basic domain and arginine-rich peptides into mammalian cells

    Microsoft Academic Search

    Li Hua Jin; Jae Hoon Bahn; Won Sik Eum; Hyeok Yil Kwon; Sang Ho Jang; Kyu Hyung Han; Tae-Cheon Kang; Moo Ho Won; Jung Hoon Kang; Sung-Woo Cho; Soo Young Choi

    2001-01-01

    Antioxidant enzymes such as superoxide dismutase (SOD) and catalase (CAT) have been considered to have a beneficial effect against various diseases mediated by reactive oxygen species (ROS). Although a variety of modified recombinant antioxidant enzymes have been generated to protect against the oxidative stresses, the lack of their transduction ability into cells resulted in limited ability to detoxify intracellular ROS.

  16. Association of the Superoxide Dismutase (V16A) and Catalase (C262T) Genetic Polymorphisms with the Clinical Outcome of Patients with Acute Paraquat Intoxication

    PubMed Central

    Hong, Joong-Rock; Seok, Su-Jin; Jeong, Du-Shin; Lee, Sang-Gon; Gil, Hyo-Wook; Yang, Jong-Oh; Lee, Eun-Young

    2010-01-01

    Background/Aims Many patients with acute paraquat (PQ) intoxication die even at low PQ concentrations, whereas others with similar concentrations recover. Therefore, it is possible that individual differences in antioxidant capacity are responsible for the variable clinical outcome in patients with acute PQ intoxication. Methods We investigated whether there was a relationship between the genetic polymorphisms of SOD (V16A), catalase (C262T), and GPX1 (C593T) in 62 patients with acute PQ intoxication and the clinical outcomes of these patients. Results The frequency of the Mn-SOD V/V, V/A, and A/A genotypes were 56.3, 43.5, and 0% in survivors and 86.9, 13.1, and 0% in non-survivors (p > 0.05). The GPX1 C/C, C/T, and T/T genotypes were present in 100, 0, and 0% of all subjects. The catalase C/C, C/T, and T/T genotypes were present in 100, 0, and 0% of survivors, and in 82.6, 17.4, and 0% of non-survivors. Neither erythrocyte SOD activity nor catalase activity were significantly different between survivors and non-survivors. Conclusions No association was found between clinical outcome of acute PQ intoxication and the genetic polymorphism of GPX1 (C593T) or the genetic polymorphisms or enzyme activity of superoxide dismutase (V16A) or catalase (C262T). PMID:21179281

  17. Purification and characterization of a mycelial catalase from Scedosporium boydii, a useful tool for specific antibody detection in patients with cystic fibrosis.

    PubMed

    Mina, Sara; Marot-Leblond, Agnès; Cimon, Bernard; Fleury, Maxime J J; Larcher, Gérald; Bouchara, Jean-Philippe; Robert, Raymond

    2015-01-01

    Scedosporium boydii is an opportunistic filamentous fungus which may be responsible for a wide variety of infections in immunocompetent and immunocompromised individuals. This fungus belongs to the Scedosporium apiospermum species complex, which usually ranks second among the filamentous fungi colonizing the airways of patients with cystic fibrosis (CF) and may lead to allergic bronchopulmonary mycoses, sensitization, or respiratory infections. Upon microbial infection, host phagocytic cells release reactive oxygen species (ROS), such as hydrogen peroxide, as part of the antimicrobial response. Catalases are known to protect pathogens against ROS by detoxification of the hydrogen peroxide. Here, we investigated the catalase equipment of Scedosporium boydii, one of the major pathogenic species in the S. apiospermum species complex. Three catalases were identified, and the mycelial catalase A1 was purified to homogeneity by a three-step chromatographic process. This enzyme is a monofunctional tetrameric protein of 460 kDa, consisting of four 82-kDa glycosylated subunits. The potential usefulness of this enzyme in serodiagnosis of S. apiospermum infections was then investigated by an enzyme-linked immunosorbent assay (ELISA), using 64 serum samples from CF patients. Whatever the species involved in the S. apiospermum complex, sera from infected patients were clearly differentiated from sera from patients with an Aspergillus fumigatus infection or those from CF patients without clinical and biological signs of a fungal infection and without any fungus recovered from sputum samples. These results suggest that catalase A1 is a good candidate for the development of an immunoassay for serodiagnosis of infections caused by the S. apiospermum complex in patients with CF. PMID:25355796

  18. Purification and Characterization of a Mycelial Catalase from Scedosporium boydii, a Useful Tool for Specific Antibody Detection in Patients with Cystic Fibrosis

    PubMed Central

    Mina, Sara; Cimon, Bernard; Larcher, Gérald; Bouchara, Jean-Philippe; Robert, Raymond

    2014-01-01

    Scedosporium boydii is an opportunistic filamentous fungus which may be responsible for a wide variety of infections in immunocompetent and immunocompromised individuals. This fungus belongs to the Scedosporium apiospermum species complex, which usually ranks second among the filamentous fungi colonizing the airways of patients with cystic fibrosis (CF) and may lead to allergic bronchopulmonary mycoses, sensitization, or respiratory infections. Upon microbial infection, host phagocytic cells release reactive oxygen species (ROS), such as hydrogen peroxide, as part of the antimicrobial response. Catalases are known to protect pathogens against ROS by detoxification of the hydrogen peroxide. Here, we investigated the catalase equipment of Scedosporium boydii, one of the major pathogenic species in the S. apiospermum species complex. Three catalases were identified, and the mycelial catalase A1 was purified to homogeneity by a three-step chromatographic process. This enzyme is a monofunctional tetrameric protein of 460 kDa, consisting of four 82-kDa glycosylated subunits. The potential usefulness of this enzyme in serodiagnosis of S. apiospermum infections was then investigated by an enzyme-linked immunosorbent assay (ELISA), using 64 serum samples from CF patients. Whatever the species involved in the S. apiospermum complex, sera from infected patients were clearly differentiated from sera from patients with an Aspergillus fumigatus infection or those from CF patients without clinical and biological signs of a fungal infection and without any fungus recovered from sputum samples. These results suggest that catalase A1 is a good candidate for the development of an immunoassay for serodiagnosis of infections caused by the S. apiospermum complex in patients with CF. PMID:25355796

  19. Revealing mechanisms of selective, concentration-dependent potentials of 4-hydroxy-2-nonenal to induce apoptosis in cancer cells through inactivation of membrane-associated catalase.

    PubMed

    Bauer, Georg; Zarkovic, Neven

    2015-04-01

    Tumor cells generate extracellular superoxide anions and are protected against superoxide anion-mediated intercellular apoptosis-inducing signaling by the expression of membrane-associated catalase. 4-Hydroxy-2-nonenal (4-HNE), a versatile second messenger generated during lipid peroxidation, has been shown to induce apoptosis selectively in malignant cells. The findings described in this paper reveal the strong, concentration-dependent potential of 4-HNE to specifically inactivate extracellular catalase of tumor cells both indirectly and directly and to consequently trigger apoptosis in malignant cells through superoxide anion-mediated intercellular apoptosis-inducing signaling. Namely, 4-HNE caused apoptosis selectively in NOX1-expressing tumor cells through inactivation of their membrane-associated catalase, thus reactivating subsequent intercellular signaling through the NO/peroxynitrite and HOCl pathways, followed by the mitochondrial pathway of apoptosis. Concentrations of 4-HNE of 1.2 µM and higher directly inactivated membrane-associated catalase of tumor cells, whereas at lower concentrations, 4-HNE triggered a complex amplificatory pathway based on initial singlet oxygen formation through H2O2 and peroxynitrite interaction. Singlet-oxygen-dependent activation of the FAS receptor and caspase-8 increased superoxide anion generation by NOX1 and amplification of singlet oxygen generation, which allowed singlet-oxygen-dependent inactivation of catalase. 4-HNE and singlet oxygen cooperate in complex autoamplificatory loops during this process. The finding of these novel anticancer pathways may be useful for understanding the role of 4-HNE in the control of malignant cells and for the optimization of ROS-dependent therapeutic approaches including antioxidant treatments. PMID:25619142

  20. Triadimefon pretreatment protects newly assembled membrane system and causes up-regulation of stress proteins in salinity stressed Amaranthus lividus L. during early germination.

    PubMed

    Bhattacharjee, Soumen

    2008-09-01

    Imposition of salinity stress during early germination imposes a secondary oxidative stress in 120-hr-old Amaranthus lividus seedlings (measured in terms of accumulation of reactive oxygen species, antioxidative defense system and oxidative membrane lipid and protein damages). Seeds of Amaranthus when treated with triadimefon along with NaCI salinity significantly enhanced the activities of catalase, peroxidase and superoxide dismutase, compared to untreated salinity stressed 5-day-old seedlings. Triadimefon treatment also reduced the accumulation of both the ROS (H2O2 and O2*-) in 5-day-old Amaranthus seedlings. When oxidative membrane damages were estimated for triadimefon treated and salinity stressed juvenile seedlings and compared with untreated salinity stressed seedlings, it shows a clear reversal in oxidative membrane damages induced by triadimefon under salinity stress. Triadimefon treatment significantly reduces the membrane lipid peroxidation and the loss of membrane protein thiol level in salinity stressed Amaranthus seedlings. That triadimefon treatment under salinity stress restores the membrane integrity and improves the post-germinative seedling growth could be supported by the data of membrane injury index (MII), relative leakage ratio (RLR), membrane permeability status (MPS), relative growth index (RGI) and mean tolerance index (MTI). SDS-PAGE of total extractible proteins revealed that some new proteins were synthesized in triadimefon treated and salinity stressed seedlings as compared to untreated and salinity stressed one. However the most remarkable feature is the up-regulation of some of the stress proteins in triadimefon treated and salinity stressed seedlings. So, it appears that significant extent of salinity tolerance exhibited by triadimefon pretreated Amaranthus seedlings could be related to the mitigation of oxidative damage to the newly assembled membrane system of juvenile tissues as well as synthesis and up-regulation of stress proteins that enhanced salinity tolerance. PMID:19295087

  1. Copper and resveratrol attenuates serum catalase, glutathione peroxidase, and element values in rats with DMBA-induced mammary carcinogenesis.

    PubMed

    Skrajnowska, Dorota; Bobrowska-Korczak, Barbara; Tokarz, Andrzej; Bialek, Slawomir; Jezierska, Ewelina; Makowska, Justyna

    2013-12-01

    In this paper, a hypothesis was assessed whether or not the intoxication with copper and supplementation with copper plus resveratrol would result in changes in the activities of catalase and glutathione peroxidase and moreover if the characteristic changes would appear in concentrations of copper, iron, calcium, magnesium, and zinc in the serum of rats with chemically induced carcinogenesis. Female Sprague-Dawley rats were divided into study groups which, apart from the standard diet, were treated with copper (42.6 mg Cu/kg food as CuSO4·5H2O) or copper plus resveratrol (0.2 mg/kg body) via gavage for a period from 40 days until 20 weeks of age. In cancer groups, the rats were treated with a dose of 80 mg/body weight of 7,12-dimethyl-1,2-benz[a]anthracene (DMBA) given in rapeseed oil at 50 and 80 days of age to induce mammary carcinogenesis. The control groups included the rats kept in the same conditions and fed with the same diet as the animals from the study groups, but not DMBA-treated. The activity of catalase significantly decreased in groups of rats with mammary carcinogenesis that were supplemented with copper (p < 0.05) or copper plus resveratrol (p < 0.001) in comparison with the control groups that received the same diets. In cancer groups of nonsupplemented rats, the increase of glutathione peroxidase activity was observed. The process of carcinogenesis and the applied supplementation significantly altered the concentrations of trace elements in serum, in particular as concerns iron and copper. The mean serum iron levels in rats with breast cancer were significantly lower than those in the control groups (p < 0.001). The mean serum copper levels significantly decreased in the groups of rats with mammary carcinogenesis that were supplemented with copper or copper plus resveratrol in comparison with the control groups that received the same diets (p < 0.001). The characteristic changes in iron content and the zinc/copper and zinc/iron ratios in blood may be used as one of the prognostic factors in breast cancer research. PMID:24213724

  2. Upregulation of Defensins in Burn Sheep Small Intestine

    PubMed Central

    Poindexter, Brian J.; Klein, Gordon L.; Milner, Stephen M.; Bick, Roger J.

    2010-01-01

    Objective: The aim of this study was to visualize and localize the sheep antimicrobials, ?-defensins 1, 2, and 3, (SBD-1, SBD-2, SBD-3), sheep neutrophil defensin alpha (SNP-1), and the cathelicidin LL-37 in sheep small intestine after burn injury, our hypothesis being that these compounds would be upregulated in an effort to overcome a compromised endothelial lining. Response to burn injury includes the release of proinflammatory cytokines and systemic immune suppression that, if untreated, can progress to multiple organ failure and death, so protective mechanisms have to be initiated and implemented. Methods: Tissue sections were probed with antibodies to the antimicrobials and then visualized with fluorescently labeled secondary antibodies and subjected to fluorescence deconvolution microscopy and image reconstruction. Results: In both the sham and burn samples, all the aforementioned antimicrobials were seen in each of the layers of small intestine, the highest concentration being localized to the epithelium. SBD-2, SBD-3, and SNP-1 were upregulated in both enterocytes and Paneth cells, while SNP-1 and LL-37 showed increases in both the inner circular and outer longitudinal muscle layers of the muscularis externa following burn injury. Each of the defensins, except SBD-1, was also seen in between the muscle layers of the externa and while burn caused slight increases of SBD-2, SBD-3, and SNP-1 in this location, LL-37 content was significantly decreased. Conclusion: That while each of these human antimicrobials is present in multiple layers of sheep small intestine, SBD-2, SBD-3, SNP-1, and LL-37 are upregulated in the specific layers of the small intestine. PMID:20076788

  3. The Dictyostelium discoideum prespore-specific catalase B functions to control late development and to protect spore viability.

    PubMed

    Garcia, Ma Xenia U; Alexander, Hannah; Mahadeo, Dana; Cotter, David A; Alexander, Stephen

    2003-06-17

    Changes in the levels of reactive oxygen species (ROS) have been associated previously with cell differentiation and development in several systems. Thus, there is interest in studying the developmental regulation of antioxidant enzymes, whose activities may modulate ROS levels and subsequent oxidant-mediated signal transduction events in specific tissues. Our recent identification in Dictyostelium discoideum of the prespore-specific catalase B (CatB) enzyme suggested (a) that the CatB enzyme functions to provide protection to the mature spores, and (b) that the CatB enzyme may have a regulatory role in cell differentiation and morphogenesis. We have now confirmed both these hypotheses. We specifically disrupted the catB gene by homologous recombination. The resulting catB null strain displays a 4-h delay in development at the time of normal catB gene expression, followed by slow and asynchronous development of fruiting bodies, taking 10 h longer than the isogenic parent strain. The expression of both prestalk- and prespore-specific genes was altered in the mutant both temporally and quantitatively, and the resultant mutant spores had increased sensitivity to H(2)O(2). This study supports the idea that CatB functions in the development of D. discoideum by regulating the level of ROS, and adds to the growing body of evidence for regulatory roles for ROS. PMID:12788229

  4. Sensitive electrochemical immunoassay of carcinoembryonic antigen with signal dual-amplification using glucose oxidase and an artificial catalase.

    PubMed

    Tang, Juan; Tang, Dianping; Li, Qunfang; Su, Biling; Qiu, Bin; Chen, Guonan

    2011-07-01

    A new dual-amplification strategy of electrochemical signal based on the catalytic recycling of the product was developed for the antigen-antibody interaction by glucose oxidase (GOD)- conjugated gold-silver hollow microspheres (AuAgHSs) coupled with an artificial catalase, Prussian blue nanoparticles (PB), on a graphene-based immunosensing platform. The first signal amplification introduced in this study was based on the labeled GOD on the AuAgHSs toward the catalytic oxidation of glucose. The generated H(2)O(2) was catalytically reduced by the immobilized PB on the graphene nanosheets with the second amplification. With a sandwich-type immunoassay format, carcinoembryonic antigen (CEA) was monitored as a model analyte by using the synthesized AuAgHSs as labels in pH 6.0 phosphate buffer containing 10mM glucose. Under optimal conditions, the electrochemical immunosensor exhibited a wide dynamic range of 0.005-50 ng mL(-1) with a low detection limit (LOD) of 1.0 pg mL(-1) CEA (at 3?). Both the intra- and inter-assay coefficients of variation (CVs) were lower than 10%. The specificity and stability of the immunosensor were acceptable. In addition, the assay was evaluated for clinical serum specimens, and received a good correlation with those obtained by the referenced electrochemiluminescent (ECL). PMID:21641413

  5. Effect of nutrition factors on the synthesis of superoxide dismutase, catalase, and membrane lipid peroxide levels in Cordyceps militaris mycelium.

    PubMed

    Wang, Zun-Sheng; Gu, Yu-Xiang; Yuan, Qin-Sheng

    2006-01-01

    Effect of carbon, nitrogen, and metal ion sources on superoxide dismutase (SOD), catalase (CAT) activities, and lipid perioxide (LPO) levels in Cordyceps militaris mycelium were investigated at stationary growth phase by step supplementing with these nutrition factors in shake-flask cultures. Mycelium was cultivated in several growth media containing different carbon sources. The observed highest SOD and CAT activities were 44.3 U/mg protein in the presence of 20% potato broth plus 2% glucose medium and 93.7 U/mg protein in presence of 20% potato broth plus 1% glucose medium, respectively. By supplementing with either yeast extract or tryptone in 0.1-0.5% concentration range, the highest SOD and CAT activities were 21.1 U/mg protein in medium supplemented with 0.1% yeast extract and 20.7 U/mg protein in medium supplemented with 0.1% tryptone, respectively. Supplementing with Cu(2+), Zn(2+), and Mn(2+) caused a stimulation of SOD synthesis. The minimum LPO level was observed at media presented Zn(2+). The time course of SOD and CAT biosynthesis showed two maxima, which correspond to the maximum of biomass. High SOD levels and low LPO levels in the medium described above indicated that the appropriate metal ions could provide a suitable protection for cells against oxygen radical damage. PMID:16392009

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

    PubMed Central

    Sofo, Adriano; Scopa, Antonio; Nuzzaci, Maria; Vitti, Antonella

    2015-01-01

    Hydrogen peroxide (H2O2), an important relatively stable non-radical reactive oxygen species (ROS) is produced by normal aerobic metabolism in plants. At low concentrations, H2O2 acts as a signal molecule involved in the regulation of specific biological/physiological processes (photosynthetic functions, cell cycle, growth and development, plant responses to biotic and abiotic stresses). Oxidative stress and eventual cell death in plants can be caused by excess H2O2 accumulation. Since stress factors provoke enhanced production of H2O2 in plants, severe damage to biomolecules can be possible due to elevated and non-metabolized cellular H2O2. Plants are endowed with H2O2-metabolizing enzymes such as catalases (CAT), ascorbate peroxidases (APX), some peroxiredoxins, glutathione/thioredoxin peroxidases, and glutathione sulfo-transferases. However, the most notably distinguished enzymes are CAT and APX since the former mainly occurs in peroxisomes and does not require a reductant for catalyzing a dismutation reaction. In particular, APX has a higher affinity for H2O2 and reduces it to H2O in chloroplasts, cytosol, mitochondria and peroxisomes, as well as in the apoplastic space, utilizing ascorbate as specific electron donor. Based on recent reports, this review highlights the role of H2O2 in plants experiencing water deficit and salinity and synthesizes major outcomes of studies on CAT and APX activity and genetic regulation in drought- and salt-stressed plants. PMID:26075872

  7. Spectroscopic investigations on the effect of N-Acetyl-L-cysteine-Capped CdTe Quantum Dots on catalase

    NASA Astrophysics Data System (ADS)

    Sun, Haoyu; Yang, Bingjun; Cui, Erqian; Liu, Rutao

    2014-11-01

    Quantum dots (QDs) are recognized as some of the most promising semiconductor nanocrystals in biomedical applications. However, the potential toxicity of QDs has aroused wide public concern. Catalase (CAT) is a common enzyme in animal and plant tissues. For the potential application of QDs in vivo, it is important to investigate the interaction of QDs with CAT. In this work, the effect of N-Acetyl-L-cysteine-Capped CdTe Quantum Dots with fluorescence emission peak at 612 nm (QDs-612) on CAT was investigated by fluorescence, synchronous fluorescence, fluorescence lifetime, ultraviolet-visible (UV-vis) absorption and circular dichroism (CD) techniques. Binding of QDs-612 to CAT caused static quenching of the fluorescence, the change of the secondary structure of CAT and the alteration of the microenvironment of tryptophan residues. The association constants K were determined to be K288K = 7.98 × 105 L mol-1 and K298K = 7.21 × 105 L mol-1. The interaction between QDs-612 and CAT was spontaneous with 1:1 stoichiometry approximately. The CAT activity was also inhibited for the bound QDs-612. This work provides direct evidence about enzyme toxicity of QDs-612 to CAT in vitro and establishes a new strategy to investigate the interaction between enzyme and QDs at a molecular level, which is helpful for clarifying the bioactivities of QDs in vivo.

  8. The induction of two biosynthetic enzymes helps Escherichia coli sustain heme synthesis and activate catalase during hydrogen peroxide stress.

    PubMed

    Mancini, Stefano; Imlay, James A

    2015-05-01

    Hydrogen peroxide pervades many natural environments, including the phagosomes that mediate cell-based immunity. Transcriptomic analysis showed that during protracted low-grade H2 O2 stress, Escherichia coli responds by activating both the OxyR defensive regulon and the Fur iron-starvation response. OxyR induced synthesis of two members of the nine-step heme biosynthetic pathway: ferrochelatase (HemH) and an isozyme of coproporphyrinogen III oxidase (HemF). Mutations that blocked either adaptation caused the accumulation of porphyrin intermediates, inadequate activation of heme enzymes, low catalase activity, defective clearance of H2 O2 and a failure to grow. Genetic analysis indicated that HemH induction is needed to compensate for iron sequestration by the mini-ferritin Dps. Dps activity protects DNA and proteins by limiting Fenton chemistry, but it interferes with the ability of HemH to acquire the iron that it needs to complete heme synthesis. HemF is a manganoprotein that displaces HemN, an iron-sulfur enzyme whose synthesis and/or stability is apparently problematic during H2 O2 stress. Thus, the primary responses to H2 O2 , including the sequestration of iron, require compensatory adjustments in the mechanisms of iron-cofactor synthesis. The results support the growing evidence that oxidative stress is primarily an iron pathology. PMID:25664592

  9. Fluctuations in total antioxidant capacity, catalase activity, and hydrogen peroxide levels of follicular fluid during bovine folliculogenesis

    PubMed Central

    Gupta, Sajal; Choi, Audrey; Yu, Hope Y.; Czerniak, Suzanne M.; Holick, Emily A.; Paolella, Louis J.; Agarwal, Ashok; Combelles, Catherine M.H.

    2011-01-01

    Follicular fluid is an important environment for oocyte development, yet current knowledge regarding its in vivo oxidant and antioxidant levels remains limited. Examining follicular fluid oxidants and antioxidants will improve understanding of their changes in vivo and contribute to optimization of in vitro maturation conditions. The aim of our study was to consider select markers, namely catalase (CAT) enzyme activity, total antioxidant capacity (TAC), and hydrogen peroxide (H2O2) in follicular fluid samples (n=503) originating from bovine antral follicles. We measured the dynamic changes in two relevant antioxidant measures and one reactive oxygen species (ROS) through stages of bovine follicular development and the estrous cycle. CAT activity and H2O2 levels decreased significantly as follicle size increased, while TAC increased significantly as follicle size increased. Lower TAC and higher H2O2 in small follicles suggest increased ROS in the initial stages of folliculogenesis. Because CAT levels are highest in follicular fluid of small follicles in the setting of an overall low TAC, CAT may represent a dominant antioxidant defense in the initial stages of folliculogenesis. Future studies must focus on other reactive oxygen species and their various scavenger types during antral folliculogenesis. PMID:21635816

  10. Progesterone Upregulates Gene Expression in Normal Human Thyroid Follicular Cells

    PubMed Central

    Bertoni, Ana Paula Santin; Brum, Ilma Simoni; Hillebrand, Ana Caroline; Furlanetto, Tania Weber

    2015-01-01

    Thyroid cancer and thyroid nodules are more prevalent in women than men, so female sex hormones may have an etiological role in these conditions. There are no data about direct effects of progesterone on thyroid cells, so the aim of the present study was to evaluate progesterone effects in the sodium-iodide symporter NIS, thyroglobulin TG, thyroperoxidase TPO, and KI-67 genes expression, in normal thyroid follicular cells, derived from human tissue. NIS, TG, TPO, and KI-67 mRNA expression increased significantly after TSH 20??UI/mL, respectively: 2.08 times, P < 0.0001; 2.39 times, P = 0.01; 1.58 times, P = 0.0003; and 1.87 times, P < 0.0001. In thyroid cells treated with 20??UI/mL TSH plus 10?nM progesterone, RNA expression of NIS, TG, and KI-67 genes increased, respectively: 1.78 times, P < 0.0001; 1.75 times, P = 0.037; and 1.95 times, P < 0.0001, and TPO mRNA expression also increased, though not significantly (1.77 times, P = 0.069). These effects were abolished by mifepristone, an antagonist of progesterone receptor, suggesting that genes involved in thyroid cell function and proliferation are upregulated by progesterone. This work provides evidence that progesterone has a direct effect on thyroid cells, upregulating genes involved in thyroid function and growth. PMID:26089899

  11. Progesterone Upregulates Gene Expression in Normal Human Thyroid Follicular Cells.

    PubMed

    Bertoni, Ana Paula Santin; Brum, Ilma Simoni; Hillebrand, Ana Caroline; Furlanetto, Tania Weber

    2015-01-01

    Thyroid cancer and thyroid nodules are more prevalent in women than men, so female sex hormones may have an etiological role in these conditions. There are no data about direct effects of progesterone on thyroid cells, so the aim of the present study was to evaluate progesterone effects in the sodium-iodide symporter NIS, thyroglobulin TG, thyroperoxidase TPO, and KI-67 genes expression, in normal thyroid follicular cells, derived from human tissue. NIS, TG, TPO, and KI-67 mRNA expression increased significantly after TSH 20??UI/mL, respectively: 2.08 times, P < 0.0001; 2.39 times, P = 0.01; 1.58 times, P = 0.0003; and 1.87 times, P < 0.0001. In thyroid cells treated with 20??UI/mL TSH plus 10?nM progesterone, RNA expression of NIS, TG, and KI-67 genes increased, respectively: 1.78 times, P < 0.0001; 1.75 times, P = 0.037; and 1.95 times, P < 0.0001, and TPO mRNA expression also increased, though not significantly (1.77 times, P = 0.069). These effects were abolished by mifepristone, an antagonist of progesterone receptor, suggesting that genes involved in thyroid cell function and proliferation are upregulated by progesterone. This work provides evidence that progesterone has a direct effect on thyroid cells, upregulating genes involved in thyroid function and growth. PMID:26089899

  12. Upregulation of BST-2/Tetherin by HIV Infection In Vivo ? §

    PubMed Central

    Homann, Stefanie; Smith, Davey; Little, Susan; Richman, Douglas; Guatelli, John

    2011-01-01

    The interferon-inducible antiviral factor BST-2 prevents several enveloped viruses, including HIV, from escaping infected cells. The HIV protein Vpu antagonizes this host defense. Little is known about the expression of BST-2 during HIV infection in vivo and whether it can be modulated to the host's advantage. We studied the expression of BST-2 on blood cells from HIV-infected patients during the acute and chronic phases of disease as well as after antiretroviral treatment (ART). The expression of BST-2 was increased on mononuclear leukocytes, including CD4-positive T lymphocytes from HIV-positive patients, compared to that on cells of uninfected controls. The expression of BST-2 was highest during acute infection and decreased to levels similar to those of uninfected individuals after ART. Treatment of primary blood mononuclear cells in vitro with alpha interferon or with Toll-like receptor (TLR) agonists increased the expression of BST-2 to levels similar to those found during infection in vivo. The interferon-induced levels were sufficient to overcome the Vpu protein in vitro, reducing the release of wild-type HIV. These data show that BST-2 is upregulated during HIV infection, consistent with its role as an interferon-stimulated gene. The data further suggest that this upregulation is sufficient to saturate the activity of Vpu and inhibit wild-type HIV. PMID:21849457

  13. Effects of hydrogen peroxide on the motility, catalase and superoxide dismutase of dam and\\/or seqA mutant of Salmonella typhimurium

    Microsoft Academic Search

    Abdelwaheb Chatti; Nadia Messaoudi; Mouadh Mihoub; Ahmed Landoulsi

    In addition to their role in the virulence attenuation of Salmonella and other pathogens, dam or seqA genes increase the sensitivity towards hydrogen peroxide. The aim of our study is to investigate the effect of H2O2 on the motility, the catalase and superoxide dismutase activities of dam and\\/or seqA mutants of Salmonella typhimurium. Our findings showed significant differences of the

  14. The katA Catalase Gene Is Regulated by OxyR in both Free-Living and Symbiotic Sinorhizobium meliloti

    PubMed Central

    Jamet, Alexandre; Kiss, Ernö; Batut, Jacques; Puppo, Alain; Hérouart, Didier

    2005-01-01

    The characterization of an oxyR insertion mutant provides evidences that katA, which encodes the unique H2O2-inducible HPII catalase, is regulated by OxyR not only in free-living Sinorhizobium meliloti but also in symbiotic S. meliloti. Moreover, oxyR is expressed independently of exogenous H2O2 and downregulates its own expression in S. meliloti. PMID:15601722

  15. Transgenic tobacco plants expressing the maize Cat2 gene have altered catalase levels that affect plant-pathogen interactions and resistance to oxidative stress

    Microsoft Academic Search

    A. N. Polidoros; P. V. Mylona; J. G. Scandalios

    2001-01-01

    Transgenic tobacco genotypes expressing the maize Cat2 gene were developed with altered catalase (CAT) levels that resulted in a moderate increase of CAT activity in two transgenic lines. Bacterial infection, with a pathogen that does not share homology with the transgene, caused local and systemic down-regulation of the steady state mRNA levels of the 35S-driven transgene in a manner resembling

  16. Isolation and characterization of a catalase gene "HuCAT3" from pitaya (Hylocereus undatus) and its expression under abiotic stress.

    PubMed

    Nie, Qiong; Gao, Guo-Li; Fan, Qing-jie; Qiao, Guang; Wen, Xiao-Peng; Liu, Tao; Peng, Zhi-Jun; Cai, Yong-Qiang

    2015-05-25

    Abiotic stresses usually cause H2O2 accumulation, with harmful effects, in plants. Catalase may play a key protective role in plant cells by detoxifying this excess H2O2. Pitaya (Hylocereus undatus) shows broad ecological adaptation due to its high tolerance to abiotic stresses, e.g. drought, heat and poor soil. However, involvement of the pitaya catalase gene (HuCAT) in tolerance to abiotic stresses is unknown. In the present study, a full-length HuCAT3 cDNA (1870 bp) was isolated from pitaya based on our previous microarray data and RACE method. The cDNA sequence and deduced amino acid sequence shared 73-77% and 75-80% identity with other plant catalases, respectively. HuCAT3 contains conserved catalase family domain and catalytic sites. Pairwise comparison and phylogenetic analysis indicated that HuCAT3 is most similar to Eriobotrya japonica CAT, followed by Dimocarpus longan CAT and Nicotiana tabacum CAT1. Expression profile analysis demonstrated that HuCAT3 is mainly expressed in green cotyledons and mature stems, and was regulated by H2O2, drought, cold and salt stress, whereas, its expression patterns and maximum expression levels varied with stress types. HuCAT activity increased as exposure to the tested stresses, and the fluctuation of HuCAT activity was consistent with HuCAT3 mRNA abundance (except for 0.5 days upon drought stress). HuCAT3 mRNA elevations and HuCAT activities changes under cold stress were also in conformity with the cold tolerances among the four genotypes. The obtained results confirmed a major role of HuCAT3 in abiotic stress response of pitaya. This may prove useful in understanding pitaya's high tolerance to abiotic stresses at molecular level. PMID:25752288

  17. Role of glutathione redox cycle and catalase in defense against oxidative stress induced by endosulfan in adrenocortical cells of rainbow trout ( Oncorhynchus mykiss)

    Microsoft Academic Search

    J. Dorval; A. Hontela

    2003-01-01

    The role of antioxidants in maintaining the functional integrity of adrenocortical cells during in vitro exposure to endosulfan, an organochlorine pesticide, was investigated in rainbow trout (Oncorhynchus mykiss). Aminotriazole (ATA), an inhibitor of catalase (CAT), l-buthionine sulfoximine (l-BSO), an inhibitor of glutathione (GSH) synthesis, and N-acetyl cysteine (NAC), a glutathione precursor, were used to investigate the role of CAT and

  18. HCV infection induces the upregulation of miR-221 in NF-?B dependent manner.

    PubMed

    Ding, Cui-Ling; Xu, Gang; Ren, Hao; Zhao, Lan-Juan; Zhao, Ping; Qi, Zhong-Tian; Wang, Wen

    2015-01-22

    The upregulation of miR-221 has been reported in variety of cancer, including HCV associated HCC, the mechanism of upregulation of miR-221 however remains unclear. In this study, it was found that miR-221 was significantly upregulated in serum of patients with HCV associated chronic hepatitis (cHCV), which suggested the possible biological significance of miR-221 in HCV infection. Important, the upregulated miR-221 was positive correlation with serum miR-122, alanine aminotransferase (ALT) and aspartate transaminase (AST), which are reported as biomarkers for liver injuries. Further studies indicated that HCVcc infection activated nuclear factor-kappa B (NF-?B) and the upregulation of miR-221 by HCVcc infection could totally blocked by NF-?B inhibitor (pyrrolidine dithiocarbamate, PDTC). In conclusion, HCVcc infection could upregulate the expression of miR-221 in NF-?B dependent manner. PMID:25433287

  19. Application of high-performance chromatographic and electrophoretic methods to the purification and characterization of glucose oxidase and catalase from Penicillium chrysogenum.

    PubMed

    Eriksson, K O; Kourteva, I; Yao, K Q; Liao, J L; Kilár, F; Hjertén, S; Chaga, G

    1987-06-26

    The high resolving power of the preparative and analytical high-performance chromatographic and electrophoretic methods recently developed in this laboratory for the separation of biopolymers has been demonstrated by the purification and characterization of glucose oxidase and catalase from Penicillium chrysogenum. Crude glucose oxidase was purified to homogeneity in one step by high-performance hydrophobic-interaction chromatography (HIC) on a pentylagarose column. Crude catalase was purified by a combination of HIC and high-performance anion-exchange chromatography on 3-diethylamino-2-hydroxypropylagarose. The homogeneity of the enzymes was monitored by high-performance electrophoresis and free zone electrophoresis. The pI values of these two enzymes determined by isoelectric focusing in the high-performance electrophoresis apparatus were 4.2 and 6.5, respectively. Their molecular weights were determined by high-performance molecular sieve chromatography on an agarose column. Glucose oxidase has a molecular weight of 175,000 and probably consists of two identical subunits, as sodium dodecyl sulphate polyacrylamide gel electrophoresis gave a molecular weight of around 72,000. The molecular weight of catalase, which is probably composed of non-identical subunits, as indicated by sodium dodecyl sulphate electrophoresis, is around 320,000. Some other characteristics of these two enzymes were also investigated, e.g., electrophoretic mobility, pH stability and optimum pH. PMID:3116021

  20. Environmental Lead Exposure, Catalase Gene, and Markers of Antioxidant and Oxidative Stress Relation to Hypertension: An Analysis Based on the EGAT Study

    PubMed Central

    Kaojarern, Sukhumpun; Chanprasertyothin, Suwannee; Panpunuan, Pachara; Petchpoung, Krittaya; Tatsaneeyapant, Aninthita; Yoovathaworn, Krongtong; Sura, Thunyachai; Kaojarern, Sming; Sritara, Piyamit

    2015-01-01

    Lead has been linked to the development of hypertension via oxidative stress. Catalase plays an important role in the disposal of hydrogen peroxide in erythrocyte and its activity was determined by CAT gene. The aims of this study were to investigate (1) the association between blood levels of antioxidant markers such as catalase, superoxide dismutase, glutathione, glutathione peroxidase, oxidative stress-marker (malondialdehyde), and blood lead level and (2) the influence of genetic polymorphism of CAT gene (rs769217) on change in blood pressure in general population of EGAT study project. This is a cross-sectional study of 332 normotensive, 432 prehypertensive, and 222 hypertensive male subjects. Hypertensive subjects had significantly higher blood lead level (5.28??g/dL) compared to normotensive (4.41??g/dL) and prehypertensive (4.55??g/dL) subjects (P < 0.05). These significant findings are also found in MDA levels. Moreover, individuals with TT genotype in hypertensive group had significantly higher blood lead and MDA levels (6.06??g/dL and 9.67??mol/L) than those with CC genotype (5.32??g/dL and 8.31??mol/L, P < 0.05). Our findings suggested that decreased blood catalase activity in this polymorphism together with low level lead exposure induced lipid peroxidation may be responsible for hypertension. PMID:25793211

  1. The peroxidase/catalase-like activities of MFe?O? (M=Mg, Ni, Cu) MNPs and their application in colorimetric biosensing of glucose.

    PubMed

    Su, Li; Qin, Wenjie; Zhang, Huige; Rahman, Zia Ur; Ren, Cuiling; Ma, Sudai; Chen, Xingguo

    2015-01-15

    MFe2O4 (M=Mg, Ni, Cu) magnetic nanoparticles (MNPs) were found to have catalytic activities similar to those of biological enzymes such as catalase and peroxidase. These nanomaterials, as bifunctional catalase/peroxidases (KatGs), not only could catalyze H2O2 to produce hydroxyl radicals, which oxidized peroxidase substrate to produce color, but also could catalyze the decomposition reaction of H2O2 into water and oxygen directly in the same condition through the catalase-like activity. And it was also found that the amount of generated hydroxyl radicals and oxygen was related to the concentration of MFe2O4 (M=Mg, Ni, Cu) MNPs. The peroxidase-like catalytic behavior of MFe2O4 MNPs was analyzed in detail. Under the optimized conditions, NiFe2O4 MNPs were used as a colorimetric biosensor for the detection of 9.4×10(-7)-2.5×10(-5) mol L(-1) glucose with a limit of detection (LOD) of 4.5×10(-7) mol L(-1). The sensor was successfully applied to glucose detection in urine sample. PMID:25127473

  2. Attenuation of Experimental Colitis in Glutathione Peroxidase 1 and Catalase Double Knockout Mice through Enhancing Regulatory T Cell Function

    PubMed Central

    Choi, Eun-Jeong; Kie, Jeong-Hae; Lim, Woosung; Lee, Hyeon Kook; Moon, Byung-In; Seoh, Ju-Young

    2014-01-01

    Reactive oxygen species (ROS) have been implicated in the progression of inflammatory diseases including inflammatory bowel diseases (IBD). Meanwhile, several studies suggested the protective role of ROS in immune-mediated inflammatory diseases, and it was recently reported that dextran sodium sulfate (DSS)-induced colitis was attenuated in mice with an elevated level of ROS due to deficiency of peroxiredoxin II. Regulatory T cells (Tregs) are critical in the prevention of IBD and Treg function was reported to be closely associated with ROS level, but it has been investigated only in lowered levels of ROS so far. In the present study, in order to clarify the relationship between ROS level and Treg function, and their role in the pathogenesis of IBD, we investigated mice with an elevated level of ROS due to deficiency of both glutathione peroxidase (GPx)-1 and catalase (Cat) for the susceptibility of DSS-induced colitis in association with Treg function. The results showed that DSS-induced colitis was attenuated and Tregs were hyperfunctional in GPx1?/? × Cat?/? mice. In vivo administration of N-acetylcysteine (NAC) aggravated DSS-induced colitis and decreased Treg function to the level comparable to WT mice. Attenuated Th17 cell differentiation from naïve CD4+ cells as well as impaired production of IL-6 and IL-17A by splenocytes upon stimulation suggested anti-inflammatory tendency of GPx1?/? × Cat?/? mice. Suppression of Stat3 activation in association with enhancement of indoleamine 2,3-dioxygenase and FoxP3 expression might be involved in the immunosuppressive mechanism of GPx1?/? × Cat?/? mice. Taken together, it is implied that ROS level is critical in the regulation of Treg function, and IBD may be attenuated in appropriately elevated levels of ROS. PMID:24743300

  3. Effects of total dissolved gas supersaturated water on lethality and catalase activity of Chinese sucker (Myxocyprinus asiaticus Bleeker).

    PubMed

    Chen, Shi-chao; Liu, Xiao-qing; Jiang, Wen; Li, Ke-feng; Du, Jun; Shen, Dan-zhou; Gong, Quan

    2012-10-01

    Total dissolved gas (TDG) supersaturation caused by dam sluicing can result in gas bubble trauma (GBT) in fish and threaten their survival. In the present study, Chinese suckers (Myxocyprinus asiaticus Bleeker) were exposed to TDG supersaturated water at levels ranging from 120% to 145% for 48 h. The median lethal concentration (LC(50)) and the median lethal time (LT(50)) were determined to evaluate acute lethal effects on Chinese suckers. The results showed that the LC(50) values of 4, 6, 8, and 10 h were 142%, 137%, 135%, and 130%, respectively. The LT(50) values were 3.2, 4.7, 7.8, 9.2, and 43.4 h, respectively, when TDG supersaturated levels were 145%, 140%, 135%, 130%, and 125%. Furthermore, the biological responses in Chinese suckers were studied by assaying the catalase (CAT) activities in gills and muscles at the supersaturation level of 140% within LT(50). The CAT activities in the gills and muscle tissues exhibited a regularity of a decrease after an increase. CAT activities in the muscles were increased significantly at 3/5LT(50) (P<0.05) and then came back to the normal level. However, there were no significant differences between the treatment group (TDG level of 140%) and the control group (TDG level of 100%) on CAT activities in the gills before 3/5LT(50) (P>0.05), but the activities were significantly lower than the normal level at 4/5LT(50) and LT(50) (P<0.05). PMID:23024046

  4. Effect of catalase and superoxide dismutase on motility, viability and acrosomal integrity of frozen-thawed cat spermatozoa.

    PubMed

    Thiangtum, K; Pinyopummin, A; Hori, T; Kawakami, E; Tsutsui, T

    2009-07-01

    The aim of this study was to evaluate the effect of antioxidant catalase (CAT) and superoxide dismutase (SOD) in semen extender on motility, viability and acrosomal integrity of frozen-thawed cat spermatozoa. Semen was collected by using an artificial vagina from five domestic cats (two ejaculates/cat). Spermatozoa were diluted in egg yolk Ttris-fructose citrate solution (EYT-FC) without glycerol and cooled at 4 degrees C for 1 h, then diluted further with EYT-FC with glycerol (7% final concentration) and 400 IU/ml of CAT (treatment 1) or SOD (treatment 2) or without antioxidants (control). Before freezing using a styrofoam box, diluted spermatozoa filled in 0.25-ml straws were equilibrated for 1 h at 4 degrees C. After thawing, spermatozoa were assessed for motility, viability and acrosomal integrity. Cryopreservation significantly impaired sperm motility, viability and acrosomal integrity (p < 0.05). However, motility, viability and acrosomal integrity of frozen-thawed cat spermatozoa in the EYT-FC with CAT, SOD and without the antioxidants were not significantly different. The average percentages of spermatozoa motility after thawing compared between control, treatment 1 and treatment 2 group were 43.5 +/- 3.2, 42 +/- 4.1 and 38 +/- 4.5; for viability: 44.8 +/- 3.5, 50.6 +/- 5.7 and 47.1 +/- 4.1 and for acrosomal integrity: 45 +/- 3.5, 44.9 +/- 3.4 and 44.4 +/- 3.3, respectively. In conclusion, adding CAT and SOD to EYT-FC did not improve motility, viability and acrosomal integrity in cryopreserved cat spermatozoa. PMID:19754607

  5. Upregulation of KCNQ1/KCNE1 K+ channels by Klotho

    PubMed Central

    Almilaji, Ahmad; Pakladok, Tatsiana; Muñoz, Carlos; Elvira, Bernat; Sopjani, Mentor; Lang, Florian

    2014-01-01

    Klotho is a transmembrane protein expressed primarily in kidney, parathyroid gland, and choroid plexus. The extracellular domain could be cleaved off and released into the systemic circulation. Klotho is in part effective as ?-glucuronidase regulating protein stability in the cell membrane. Klotho is a major determinant of aging and life span. Overexpression of Klotho increases and Klotho deficiency decreases life span. Klotho deficiency may further result in hearing loss and cardiac arrhythmia. The present study explored whether Klotho modifies activity and protein abundance of KCNQ1/KCNE1, a K+ channel required for proper hearing and cardiac repolarization. To this end, cRNA encoding KCNQ1/KCNE1 was injected in Xenopus oocytes with or without additional injection of cRNA encoding Klotho. KCNQ1/KCNE1 expressing oocytes were treated with human recombinant Klotho protein (30 ng/ml) for 24 h. Moreover, oocytes which express both KCNQ1/KCNE1 and Klotho were treated with 10 µM DSAL (D-saccharic acid-1,4-lactone), a ?-glucuronidase inhibitor. The KCNQ1/KCNE1 depolarization-induced current (IKs) was determined utilizing dual electrode voltage clamp, while KCNQ1/KCNE1 protein abundance in the cell membrane was visualized utilizing specific antibody binding and quantified by chemiluminescence. KCNQ1/KCNE1 channel activity and KCNQ1/KCNE1 protein abundance were upregulated by coexpression of Klotho. The effect was mimicked by treatment with human recombinant Klotho protein (30 ng/ml) and inhibited by DSAL (10 µM). In conclusion, Klotho upregulates KCNQ1/KCNE1 channel activity by 'mainly' enhancing channel protein abundance in the plasma cell membrane, an effect at least partially mediated through the ?-glucuronidase activity of Klotho protein. PMID:24457979

  6. Ferric uptake regulator (Fur) mutants of Pseudomonas aeruginosa demonstrate defective siderophore-mediated iron uptake, altered aerobic growth, and decreased superoxide dismutase and catalase activities.

    PubMed Central

    Hassett, D J; Sokol, P A; Howell, M L; Ma, J F; Schweizer, H T; Ochsner, U; Vasil, M L

    1996-01-01

    Pseudomonas aeruginosa is considered a strict aerobe that possesses several enzymes important in the disposal of toxic oxygen reduction products including iron- and manganese-cofactored superoxide dismutase and catalase. At present, the nature of the regulation of these enzymes in P. aeruginosa Is not understood. To address these issues, we used two mutants called A4 and C6 which express altered Fur (named for ferric uptake regulation) proteins and constitutively produce the siderophores pyochelin and pyoverdin. Both mutants required a significant lag phase prior to log-phase aerobic growth, but this lag was not as apparent when the organisms were grown under microaerobic conditions. The addition of iron salts to mutant A4 and, to a greater extent, C6 cultures allowed for an increased growth rate under both conditions relative to that of bacteria without added iron. Increased manganese superoxide dismutase (Mn-SOD) and decreased catalase activities were also apparent in the mutants, although the second catalase, KatB, was detected in cell extracts of each fur mutant. Iron deprivation by the addition of the iron chelator 2,2'-dipyridyl to wild-type bacteria produced an increase in Mn-SOD activity and a decrease in total catalase activity, similar to the fur mutant phenotype. Purified wild-type Fur bound more avidly than mutant Fur to a PCR product containing two palindromic 19-bp "iron box" regions controlling expression of an operon containing the sodA gene that encodes Mn-SOD. All mutants were defective in both ferripyochelin- and ferripyoverdin-mediated iron uptake. Two mutants of strain PAO1, defective in pyoverdin but not pyochelin biosynthesis, produced increased Mn-SOD activity. Sensitivity to both the redox-cycling agent paraquat and hydrogen peroxide was greater in each mutant than in the wild-type strain. In summary, the results indicate that mutations in the P. aeruginosa fur locus affect aerobic growth and SOD and catalase activities in P. aeruginosa. We postulate that reduced siderophore-mediated iron uptake, especially that by pyoverdin, may be one possible mechanism contributing to such effect. PMID:8763923

  7. Poxue Huayu and Tianjing Busui Decoction for cerebral hemorrhage (Upregulation of neurotrophic factor expression): Upregulation of neurotrophic factor expression

    PubMed Central

    Ren, Jixiang; Zhou, Xiangyu; Wang, Jian; Zhao, Jianjun; Zhang, Pengguo

    2013-01-01

    This study established a rat model of cerebral hemorrhage by injecting autologous anticoagulated blood. Rat models were intragastrically administered 5, 10, 20 g/kg Poxue Huayu and Tianjing Busui Decoction, supplemented with Hirudo, raw rhubarb, raw Pollen Typhae, gadfly, Fructrs Trichosanthis, Radix Notoginseng, Rhizoma Acori Talarinowii, and glue of tortoise plastron, once a day, for 14 consecutive days. Results demonstrated that brain water content significantly reduced in rats with cerebral hemorrhage, and intracerebral hematoma volume markedly reduced after treatment. Immunohistochemical staining revealed that brain-derived neurotrophic factor, tyrosine kinase B and vascular endothelial growth factor expression noticeably increased around the surrounding hematoma. Reverse transcription-PCR revealed that brain-derived neurotrophic factor and tyrosine kinase B mRNA expression significantly increased around the surrounding hematoma. Neurologic impairment obviously reduced. These results indicated that Poxue Huayu and Tianjing Busui Decoction exert therapeutic effects on cerebral hemorrhage by upregulating the expression of brain-derived neurotrophic factor. PMID:25206512

  8. Primary sequence and activity analyses of a catalase from Ascaris suum 1 Note: Nucleotide sequence data reported in this paper are available in the GenBank TM data base under the accession number Y10611. 1

    Microsoft Academic Search

    Volker H. O. Eckelt; Eva Liebau; Rolf D. Walter; Kimberly Henkle-Dührsen

    1998-01-01

    A complete cDNA encoding the catalase (EC 1.11.1.6) has been isolated from the parasitic nematode Ascaris suum (AsCAT). The active-site residues, the residues involved in ligand interaction, and NADPH-binding residues of the bovine liver catalase-type enzyme are highly conserved in the AsCAT predicted amino acid sequence. To confirm that the AsCAT cDNA encodes a functional enzyme, active recombinant protein (rAsCAT)

  9. Clonal spread of catalase-negative ST5/SCCmec II Staphylococcus aureus carrying the staphylococcal enterotoxin A (sea), staphylococcal enterotoxin b (seb), and toxic shock toxin (tst) virulence genes.

    PubMed

    Lee, Hae Kyung; Kim, Jung-Beom; Kim, Hyunjung; Jekarl, Dong Wook; Kim, Yang Ree; Yu, Jin Kyung; Park, Yeon-Joon

    2014-01-01

    17 catalase-negative methicillin-resistant Staphylococcus aureus (MRSA) isolates were recovered from respiratory specimens of patients at a 700-bed hospital in Korea. The goal of this study was to determine the molecular characteristics of catalase-negative MRSA strains in Korea for the first time. Characteristics that we explored included kat A gene mutation sequence, sequence type, staphylococcal cassette chromosome (SCC) mec subtype classification, and toxin gene profiles. All 17 isolates showed similar pulsed field gel electrophoresis (PFGE) pattern. Four mutations were identified in the kat A gene of a representative catalase-negative MRSA strain: A602G causing a histidine 201 to arginine change, A695T causing a glutamic acid 232 to valine change, T778A causing a tryptophan 260 to arginine change, and G1438A causing a glycine 480 to serine change. Previous studies suggest that the A695T and T778A mutations may have strong effects on the catalase activity of catalase-negative MRSA. The sequence type (ST) and SCCmec type of this isolate were ST 5 and SCCmec type II, respectively. All 17 isolates harbored toxic shock toxin (tst), staphylococcal enterotoxin A (sea), and staphylococcal enterotoxin B (seb) virulence genes. The mortality rate of the present study was 11.8%, suggesting that the clinical relevance of catalase-negative MRSA requires further study in the future. PMID:25361922

  10. Upregulation of Heat Shock Proteins is Essential for Cold Survival during Insect Diapause

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Diapause, the dormancy common to overwintering insects, evokes a unique pattern of gene expression. In the flesh fly most, but not all, of the fly’s heat shock proteins (Hsps) are upregulated. The diapause upregulated Hsps include two members of the Hsp70 family, one member of the Hsp60 family (TC...

  11. Exercise training reverses age-induced inducible nitric oxide synthase upregulation 

    E-print Network

    Song, Wook

    2005-02-17

    EXERCISE TRAINING REVERSES AGE-INDUCED INDUCIBLE NITRIC OXIDE SYNTHASE UPREGULATION A Dissertation by WOOK SONG Submitted to the Office of Graduate Studies of Texas A&M University in partial fulfillment... of the requirements for the degree of DOCTOR OF PHILOSOPHY December 2003 Major Subject: Kinesiology EXERCISE TRAINING REVERSES AGE-INDUCED INDUCIBLE NITRIC OXIDE SYNTHASE UPREGULATION A Dissertation by WOOK SONG...

  12. Upregulation of aquaporin 2 water channel expression in pregnant rats.

    PubMed Central

    Ohara, M; Martin, P Y; Xu, D L; St John, J; Pattison, T A; Kim, J K; Schrier, R W

    1998-01-01

    Water retention is characteristic of pregnancy but the mechanism(s) of the altered water metabolism has yet to be elucidated. The collecting duct water channel, aquaporin 2 (AQP2), plays a pivotal role in the renal water regulation, and we hypothesized that AQP2 expression could be modified during pregnancy. Sprague-Dawley female rats were studied on days 7 (P7), 14 (P14), and 20 (P20) of pregnancy, and expression of AQP2 in papillae was examined. Nonpregnant (NP) littermates were used as controls. Plasma osmolalities were significantly lower in pregnant rats by day 7 of gestation (P7 283.8+/-1.82, P14 284.3+/-1.64, P < 0.001, P20 282. 4+/-1.32, P < 0.0001, vs. NP 291.8+/-1.06 mosmol/kgH2O). However, plasma vasopressin concentrations in pregnant rats were not significantly different than in nonpregnant rats (NP 1.03+/-0.14, P7 1.11+/-0.21, P14 1.15+/-0.21, P20 1.36+/-0.24 pg/ml, NS). The mRNA of AQP2 was increased early during pregnancy: AQP2/beta actin: P7 196+/-17.9, P14 200+/-6.8, and P20 208+/-15.5%, P < 0.005 vs. NP (100+/-11.1%). AQP2 protein was also increased during pregnancy: AQP2 protein: P7 269+/-10.0, P14 251+/-12.0, P < 0.0001, and P20 250+/-13.6%, P < 0.001 vs. NP (100+/-12.5%). The effect of V2 vasopressin receptor antagonist, OPC-31260, was then investigated. AQP2 mRNA was suppressed significantly by OPC-31260 administration to P14 rats (AQP2/beta actin: P14 with OPC-31260 39.6+/-1.7%, P < 0.001 vs. P14 with vehicle) and was decreased to the same level of expression as NP rats receiving OPC-31260. Similar findings were found with the analysis of AQP2 protein. The decreased plasma osmolality of P14 rats was not modified by OPC-31260. The results of the study indicate that upregulation of AQP2 contributes to the water retention in pregnancy through a V2 receptor-mediated effect. In addition to vasopressin, other factors may be involved in this upregulation. PMID:9486978

  13. Tumor Cells Upregulate Normoxic HIF-1? in Response to Doxorubicin

    PubMed Central

    Cao, Yiting; Eble, Joseph M.; Moon, Ejung; Yuan, Hong; Weitzel, Douglas H.; Landon, Chelsea D.; Nien, Charleen Yu-Chih; Hanna, Gabi; Rich, Jeremy N.; Provenzale, James M.; Dewhirst, Mark W.

    2013-01-01

    Hypoxia-inducible factor 1 (HIF-1) is a master transcription factor that controls cellular homeostasis. While its activation benefits normal tissue, HIF-1 activation in tumors is a major risk factor for angiogenesis, therapeutic resistance and poor prognosis. HIF-1 activity is usually suppressed under normoxic conditions because of rapid oxygen-dependent degradation of HIF-1?. Here we show that under normoxic conditions HIF-1? is upregulated in tumor cells in response to doxorubicin, a chemotherapy used to treat many cancers. Doxorubicin also enhanced VEGF secretion by normoxic tumor cells and stimulated tumor angiogenesis. Doxorubicin-induced accumulation of HIF-1? in normoxic cells was caused by increased expression and activation of STAT1, the activation of which stimulated expression of iNOS and its synthesis of NO in tumor cells. Mechanistic investigations established that blocking NO synthesis or STAT1 activation was sufficient to attenuate the HIF-1? accumulation induced by doxorubicin in normoxic cancer cells. To our knowledge, this is the first report that a chemotherapeutic drug can induce HIF-1? accumulation in normoxic cells, an efficacy-limiting activity. Our results argue that HIF-1? targeting strategies may enhance doxorubicin efficacy. More generally, they suggest a broader perspective on the design of combination chemotherapy approaches with immediate clinical impact. PMID:23959856

  14. Upregulation of p21Cip1 in activated glial cells.

    PubMed

    Tusell, Josep Maria; Ejarque-Ortiz, Aroa; Mancera, Pilar; Solà, Carme; Saura, Josep; Serratosa, Joan

    2009-04-01

    The cdk inhibitor p21(Cip1), also named p21(Cip1/Waf1), is intimately involved in coupling growth arrest to cellular differentiation in several cell types. p21(Cip1) is a multifunctional protein that might regulate cell-cycle progression at different levels. In a recent study, we found no differences in the rate of proliferation between glial cells from wild-type and p21(Cip1-/-) mice. In the present study, we examined differences in glial activation between glial cells from wild-type and p21(Cip1-/-) mice, using mixed glial cultures, microglia-enriched cultures, and astrocyte-enriched cultures. We compared the effect of lipopolysaccharide and two forms (oligomeric and fibrillar) of the 1-42 beta-amyloid peptide on glial activation. We observed an attenuation of nuclear translocation of the nuclear factor kappa-B in p21(Cip1-/-) glial cells, when compared with glial cells from wild-type mice. In contrast, tumor necrosis factor-alpha release was enhanced in p21(Cip1-/-)microglial cells. In addition glial activation induced by lipopolysaccharide and the fibrillar form of the 1-42 beta-amyloid peptide upregulated p21(Cip1). Our results support a role for p21(Cip1) in the activation of glial cells, particularly in microglia. PMID:18814231

  15. RhoA controls Wnt upregulation on microstructured titanium surfaces.

    PubMed

    Lumetti, Simone; Mazzotta, Silvia; Ferrillo, Sara; Piergianni, Maddalena; Piemontese, Marilina; Passeri, Giovanni; Macaluso, Guido Maria; Galli, Carlo

    2014-01-01

    Rough topography enhances the activation of Wnt canonical signaling in vitro, and this mediates its effects on cell differentiation. However, the molecular mechanisms underlying topography-dependent control of Wnt signaling are still poorly understood. As the small GTPase RhoA controls cytoskeletal reorganization and actomyosin-induced tensional forces, we hypothesized that RhoA could affect the activation of Wnt signaling in cells on micropatterned titanium surfaces. G-LISA assay revealed that RhoA activation was higher in C2C12 cells on rough (SLA) surfaces under basal conditions than on smooth (Polished) titanium. Transfection with dominant negative RhoA decreased Wnt activation by normalized TCF-Luc activity on SLA, whilst transfection with constitutively active RhoA increased TCF-Luc activation on Polished titanium. One mM Myosin II inhibitor Blebbistatin increased RhoA activation but decreased Wnt activation on SLA surfaces, indicating that tension-generating structures are required for canonical Wnt modulation on titanium surfaces. Actin inhibitor Cytochalasin markedly enhanced RhoA and TCF-Luc activation on both surfaces and increased the expression of differentiation markers in murine osteoblastic MC3T3 cells. Taken together, these data show that RhoA is upregulated in cells on rough surfaces and it affects the activation of Wnt canonical signaling through Myosin II modulation. PMID:24949442

  16. Selective Th2 Upregulation by Crocus sativus: A Neutraceutical Spice.

    PubMed

    Bani, Sarang; Pandey, Anjali; Agnihotri, Vijai K; Pathania, Vijaylata; Singh, Bikram

    2011-01-01

    The immunomodulatory activity of an Indian neutraceutical spice, saffron (Crocus sativus) was studied on Th(1) and Th(2) limbs of the immune system. Oral administration of alcoholic extract of Crocus sativus (ACS) at graded dose levels from 1.56-50?mg/kg p.o. potentiated the Th(2) response of humoral immunity causing the significant increases in agglutinating antibody titre in mice at a dose of 6.25?mg/kg and an elevation of CD19(+) B cells and IL-4 cytokine, a signature cytokine of Th(2) pathway. Appreciable elevation in levels of IgG-1 and IgM antibodies of the primary and secondary immune response was observed. However, ACS showed no appreciable expression of the Th(1) cytokines IL-2 (growth factor for CD4(+) T cells) and IFN-? (signature cytokine of Th(1) response). A significant modulation of immune reactivity was observed in all the animal models used. This paper represents the selective upregulation of the Th(2) response of the test material and suggests its use for subsequent selective Th(2) immunomodulation. PMID:20953384

  17. Osteopontin Upregulates the Expression of Glucose Transporters in Osteosarcoma Cells

    PubMed Central

    Hsieh, I-Shan; Yang, Rong-Sen; Fu, Wen-Mei

    2014-01-01

    Osteosarcoma is the most common primary malignancy of bone. Even after the traditional standard surgical therapy, metastasis still occurs in a high percentage of patients. Glucose is an important source of metabolic energy for tumor proliferation and survival. Tumors usually overexpress glucose transporters, especially hypoxia-responsive glucose transporter 1 and glucose transporter 3. Osteopontin, hypoxia-responsive glucose transporter 1, and glucose transporter 3 are overexpressed in many types of tumors and have been linked to tumorigenesis and metastasis. In this study, we investigated the regulation of glucose transporters by osteopontin in osteosarcoma. We observed that both glucose transporters and osteopontin were upregulated in hypoxic human osteosarcoma cells. Endogenously released osteopontin regulated the expression of glucose transporter 1 and glucose transporter 3 in osteosarcoma and enhanced glucose uptake into cells via the ?v?3 integrin. Knockdown of osteopontin induced cell death in 20% of osteosarcoma cells. Phloretin, a glucose transporter inhibitor, also caused cell death by treatment alone. The phloretin-induced cell death was significantly enhanced in osteopontin knockdown osteosarcoma cells. Combination of a low dose of phloretin and chemotherapeutic drugs, such as daunomycin, 5-Fu, etoposide, and methotrexate, exhibited synergistic cytotoxic effects in three osteosarcoma cell lines. Inhibition of glucose transporters markedly potentiated the apoptotic sensitivity of chemotherapeutic drugs in osteosarcoma. These results indicate that the combination of a low dose of a glucose transporter inhibitor with cytotoxic drugs may be beneficial for treating osteosarcoma patients. PMID:25310823

  18. Resveratrol protects human lens epithelial cells against H2O2-induced oxidative stress by increasing catalase, SOD-1, and HO-1 expression

    PubMed Central

    Zheng, Yi; Liu, Yaohua; Ge, Jinying; Wang, Xiaoyuan; Liu, Lijuan; Bu, Zhigao

    2010-01-01

    Purpose Oxidative damage induced by H2O2 treatment can irreversibly damage the lens epithelium, resulting in cell death and cataract. Whether the effects of oxidative stress could be attenuated in cultured human lens epithelial cells by incubation with resveratrol (RES) is still unknown. In the present study, we examined the function of resveratrol in protecting human lens epithelial B-3 (HLEB-3) cells against H2O2 induced cell death and cell apoptosis, its role in reducing H2O2 induced intracellular reactive oxygen species (ROS) accumulation, and investigated the mechanism by which resveratrol underlies the effect. Methods HLEB-3 cells, a human lens epithelial cell line, were exposed to 100 ?M H2O2 with or without RES pre-treatment at different concentrations for different time duration. Cell viabilities were monitored by 4-[3-[4-iodophenyl]-2-4(4-nitrophenyl)-2H-5-tetrazolio-1,3-benzene disulfonate] (WST-1) assay. The apoptosis rate and ROS generation were detected by flow cytometric analysis. Expression levels of superoxide dismutases-1 (SOD-1), catalase, and heme oxygenase-1 (HO-1) proteins were measured by western-blotting analysis. p38 and c-jun N terminal kinase (JNK) activation was also evaluated by western-blotting analysis. Results Resveratrol clearly reduced H2O2 induced cell apoptosis and ROS accumulation; protected HLEB-3 cells from H2O2 induced oxidative damage, and increased the expression levels of SOD-1, catalase, and HO-1. Further studies showed that RES also inhibited H2O2 induced p38 and JNK phosphorylation. Conclusions These findings suggested that RES protected HLEB-3 cells from H2O2 induced oxidative damage, presumably by inducing three antioxidative enzymes including catalase, SOD-1, and HO-1. PMID:20806083

  19. Tissue-specific methylation of individual CpG dinucleotides in the 5{prime} upstream region of the mouse catalase gene (Cas-1)

    SciTech Connect

    Pillay, I.L.; Singh, S.M. [Univ. of Western Ontario (Canada)

    1994-09-01

    The intracellular antioxidant enzyme, catalase, is encoded by a gene whose level of expression in different organisms, including humans, varies with tissue-type. The {open_quotes}TATA-less{close_quotes} 5{prime} upstream region of the catalase gene, in mice and humans, contains a CpG island. Such CG-rich regions are target sites for cytosine methylation and have been implicated in tissue-specific gene expression. However, the methylation status of individual CpG dinucleotides and their significance in gene expression has not been established. A 275 bp fragment within the 5{prime} region of Cas-1 was evaluated for CpG methylation. HpaII digestion of genomic DNA, followed by polymerase chain reaction amplification (HpaII-PCR), suggests that at least one of three CCGG is not methylated in nine different somatic tissues that express this enzyme at various levels. In contrast, all three CCGG sites are methylated in DNA from sperm and spleen. Further examination of the methylation specificity of individual CCGG sites was conducted using sodium bisulfite modification of genomic DNA followed by HPaII-PCR. Sodium bisulfite modifies non-methylated cytosines to uracils, changing a CG to a TG dinucleotide. This nucleotide substitution eliminates HpaII sites and allows the methylation status of each of the CCGG sites to be assessed. The ability to discern the number and combination of methylated sites within the 5{prime} region of a gene permits the determination of a possible correlation between differential methylation patterns and temporal/spatial gene regulation. Analysis of differential methylation, using the mouse catalase gene as a model, provides further insight into CpG methylation as one mechanism of mammalian gene regulation.

  20. Upregulation of cognitive control networks in older adults' speech comprehension.

    PubMed

    Erb, Julia; Obleser, Jonas

    2013-01-01

    Speech comprehension abilities decline with age and with age-related hearing loss, but it is unclear how this decline expresses in terms of central neural mechanisms. The current study examined neural speech processing in a group of older adults (aged 56-77, n = 16, with varying degrees of sensorineural hearing loss), and compared them to a cohort of young adults (aged 22-31, n = 30, self-reported normal hearing). In a functional MRI experiment, listeners heard and repeated back degraded sentences (4-band vocoded, where the temporal envelope of the acoustic signal is preserved, while the spectral information is substantially degraded). Behaviorally, older adults adapted to degraded speech at the same rate as young listeners, although their overall comprehension of degraded speech was lower. Neurally, both older and young adults relied on the left anterior insula for degraded more than clear speech perception. However, anterior insula engagement in older adults was dependent on hearing acuity. Young adults additionally employed the anterior cingulate cortex (ACC). Interestingly, this age group × degradation interaction was driven by a reduced dynamic range in older adults who displayed elevated levels of ACC activity for both degraded and clear speech, consistent with a persistent upregulation in cognitive control irrespective of task difficulty. For correct speech comprehension, older adults relied on the middle frontal gyrus in addition to a core speech comprehension network recruited by younger adults suggestive of a compensatory mechanism. Taken together, the results indicate that older adults increasingly recruit cognitive control networks, even under optimal listening conditions, at the expense of these systems' dynamic range. PMID:24399939

  1. Cystatin SN Upregulation in Patients with Seasonal Allergic Rhinitis

    PubMed Central

    Imoto, Yoshimasa; Tokunaga, Takahiro; Matsumoto, Yuri; Hamada, Yuko; Ono, Mizuho; Yamada, Takechiyo; Ito, Yumi; Arinami, Tadao; Okano, Mitsuhiro; Noguchi, Emiko; Fujieda, Shigeharu

    2013-01-01

    Seasonal allergic rhinitis (SAR) to the Japanese cedar, Cryptomeria japonica (JC) pollen is an IgE-mediated type I allergy affecting nasal mucosa. However, the molecular events underlying its development remain unclear. We sought to identify SAR-associated altered gene expression in nasal epithelial cells during natural exposure to JC pollen. We recruited study participants in 2009 and 2010 and collected nasal epithelial cells between February and April, which is the period of natural pollen dispersion. Fifteen patients with SAR-JC and 13 control subjects were enrolled in 2009, and 17 SAR-JC patients, 13 sensitized asymptomatic subjects (Sensitized), and 15 control subjects were enrolled in 2010. Total RNA was extracted from nasal epithelial cells and 8 SAR-JC patients and 6 control subjects in 2009 were subjected to microarray analysis with the Illumina HumanRef-8 Expression BeadChip platform. Allergen-stimulated histamine release was examined in the peripheral blood basophils isolated from patients with SAR. We identified 32 genes with significantly altered expression during allergen exposure. One of these, CST1 encodes the cysteine protease inhibitor, cystatin SN. CST1 expression in nasal epithelial cells was significantly upregulated in both the 2009 and 2010 SAR-JC groups compared with the control groups. Immunohistochemical staining confirmed the increased expression of CST1 in the nasal epithelial cells of SAR patients. Addition of exogenous CST1 to basophils inhibited JC allergen-stimulated histamine release in vitro. We propose that CST1 may contribute to inactivation of protease allergens and help re-establish homeostasis of the nasal membranes. PMID:23950865

  2. Upregulation of cognitive control networks in older adults’ speech comprehension

    PubMed Central

    Erb, Julia; Obleser, Jonas

    2013-01-01

    Speech comprehension abilities decline with age and with age-related hearing loss, but it is unclear how this decline expresses in terms of central neural mechanisms. The current study examined neural speech processing in a group of older adults (aged 56–77, n = 16, with varying degrees of sensorineural hearing loss), and compared them to a cohort of young adults (aged 22–31, n = 30, self-reported normal hearing). In a functional MRI experiment, listeners heard and repeated back degraded sentences (4-band vocoded, where the temporal envelope of the acoustic signal is preserved, while the spectral information is substantially degraded). Behaviorally, older adults adapted to degraded speech at the same rate as young listeners, although their overall comprehension of degraded speech was lower. Neurally, both older and young adults relied on the left anterior insula for degraded more than clear speech perception. However, anterior insula engagement in older adults was dependent on hearing acuity. Young adults additionally employed the anterior cingulate cortex (ACC). Interestingly, this age group × degradation interaction was driven by a reduced dynamic range in older adults who displayed elevated levels of ACC activity for both degraded and clear speech, consistent with a persistent upregulation in cognitive control irrespective of task difficulty. For correct speech comprehension, older adults relied on the middle frontal gyrus in addition to a core speech comprehension network recruited by younger adults suggestive of a compensatory mechanism. Taken together, the results indicate that older adults increasingly recruit cognitive control networks, even under optimal listening conditions, at the expense of these systems’ dynamic range. PMID:24399939

  3. Quercetin up-regulates mitochondrial complex-I activity to protect against programmed cell death in rotenone model of Parkinson's disease in rats.

    PubMed

    Karuppagounder, S S; Madathil, S K; Pandey, M; Haobam, R; Rajamma, U; Mohanakumar, K P

    2013-04-16

    We tested quercetin, a dietary bioflavonoid with potent free radical scavenging action and antioxidant activity, for its neuroprotective effects in rotenone-induced hemi-parkinsonian rats. Rats were infused unilaterally with rotenone into the substantia nigra, and quercetin (25-75mg/kg, i.p.) was administered at 12-h intervals for 4days, and analyzed on the 5th day. Amphetamine- or apomorphine-induced unilateral rotations were significantly reduced in quercetin-treated rats, when analyzed on 14th or 16th day post-surgery, respectively. Quercetin possessed potent hydroxyl radical scavenging action in a cells-free, Fenton-like reaction in test tubes, and in isolated mitochondria when measured by salicylate hydroxylation method. We observed dose-dependent attenuation of the rotenone-induced loss in striatal dopamine, and nigral oxidized and reduced glutathione, as well as the increases in endogenous antioxidant enzymes (catalase and superoxide dismutase) activities supporting the notion that quercetin-effect is mediated via its powerful hydroxyl radicals-scavenging and antioxidant actions. Quercetin's dose-dependent ability to up-regulate mitochondrial complex-I activity, as evidenced by NADH-oxidation, and as seen in blue native-polyacrylamide gel electrophoresis (PAGE) staining in both the contra- and ipsi-lateral nigra suggests the containment of reactive oxygen production at the mitochondrial level. Rotenone-induced induction of NADH-diaphorase activity in the nigral neurons, and its attenuation by quercetin pointed to the possible involvement of nitric oxide too. Reversal of neuronal death induced by rotenone as observed by increased tyrosine hydroxylase-positive cells and decreased TdT-mediated dUTP nick end-labeling (TUNEL) staining in the substantia nigra confirmed the potential of quercetin to revamp dopaminergic cells following oxidative stress mediated programmed cell death and neuronal demise. The present study strongly implicates quercetin's potential ability to repair mitochondrial electron transport defects and to up-regulate its function as the basis of neuroprotection observed in a mitochondrial neurotoxin-induced Parkinsonism. PMID:23357119

  4. Evaluation of the influence of housefly maggot meal (magmeal) diets on catalase, glutathione S-transferase and glycogen concentration in the liver of Oreochromis niloticus fingerling.

    PubMed

    Ogunji, Johnny O; Nimptsch, Jorge; Wiegand, Claudia; Schulz, Carsten

    2007-08-01

    Influence of housefly maggot meal (magmeal) diets on the activities of catalase (CAT), glutathione S-transferase (GST) and glycogen concentration in liver of Tilapia Oreochromis niloticus fingerling was evaluated. Triplicate groups of fifteen fish (initial average weight 2.0+/-0.1 g) were fed eight weeks with seven test diets (in average 36% crude protein, dry matter) formulated by replacing fish meal with magmeal. Percentage body weight gain (591-724.46%), food conversion ratio (1.05-1.22) and standard growth rate (3.45-3.76) in all feeding groups were not significantly different (P<0.05). No significant difference (P<0.05) was observed in liver glycogen reserve (175.27-236.88 micromol g(-1)) among the fish groups. Hepatic catalase activity also did not differ significantly. However, elevated glutathione S-transferases activities were observed when fish received higher dietary magmeal concentration. This might have been temporary with no real physiological implication when appraised by the growth responses. These results indicate that magmeal was well utilized by the fish and its incorporation into tilapia diets seems to have no oxidative stress generating effect on fish metabolism and may not be containing any compound that stimulates the generation of reactive oxygen species. Magmeal can effectively be used as an alternative protein source in tilapia fingerling production. PMID:17400494

  5. Brain heparanase expression is upregulated during postnatal development and hypoxia-induced neovascularization in adult rats

    E-print Network

    Boyer, Edmond

    of tumor cells. However, heparanase expression in non-invasive and non-immune tissue, including brain, hasBrain heparanase expression is upregulated during postnatal development and hypoxia rat that heparanase transcript is differentially expressed according to brain area

  6. TGF-?1 up-regulates connexin43 expression: a potential mechanism for human trophoblast cell differentiation.

    PubMed

    Cheng, Jung-Chien; Chang, Hsun-Ming; Fang, Lanlan; Sun, Ying-Pu; Leung, Peter C K

    2015-07-01

    Connexin43 (Cx43)-mediated gap junctional intercellular communication (GJIC) are required for human trophoblast differentiation. To date, whether Cx43 mediates TGF-?1-induced trophoblast differentiation has not been determined. We showed that treatment with TGF-?1 increased Cx43 expression and GJIC in HTR-8/SVneo human trophoblast cells. In addition, Smad and ERK1/2 signaling pathways were involved in TGF-?1-induced up-regulation of Cx43. Moreover, TGF-?1 increased the expression of the syncytiotrophoblast marker, ?-hCG. Importantly, knockdown of Cx43 abolished the TGF-?1-induced up-regulation of ?-hCG. Furthermore, overexpression of Cx43 up-regulated ?-hCG expression. These results provide evidence that Cx43 and GJIC activity are up-regulated by TGF-?1 in human trophoblast cells, which subsequently contributes to TGF-?1-induced trophoblast differentiation. PMID:25560303

  7. Synergy between broccoli sprout extract and selenium in the upregulation of thioredoxin reductase in human hepatocytes

    Microsoft Academic Search

    Dan Li; Kun Wu; A. Forbes Howie; Geoffrey J. Beckett; Wei Wang; Yongping Bao

    2008-01-01

    Dietary isothiocyanates and selenium (Se) can up-regulate thioredoxin reductase 1 (TR1) in cultured human HepG2 and MCF-7 cells [Zhang et al. (2003). Synergy between sulforaphane and selenium in the induction of thioredoxin reductase 1 requires both transcriptional and translational modulation. Carcinogenesis, 24, 497–503; Wang et al. (2005). Sulforaphane, erucin and iberin up-regulate thioredoxin reductase expression in human MCF-7 cells. Journal

  8. Human Cytomegalovirus Upregulates Expression of the Lectin Galectin 9 via Induction of Beta Interferon

    PubMed Central

    McSharry, Brian P.; Forbes, Simone K.; Cao, John Z.; Avdic, Selmir; Machala, Emily A.; Gottlieb, David J.; Abendroth, Allison

    2014-01-01

    Regulation of the lectin galectin 9 (Gal-9) was investigated for the first time during human cytomegalovirus (HCMV) infection. Gal-9 transcription was significantly upregulated in transplant recipients with reactivated HCMV in vivo. In vitro, Gal-9 was potently upregulated by HCMV independently of viral gene expression, with interferon beta (IFN-?) identified as the mediator of this effect. This study defines an immunoregulatory protein potently increased by HCMV infection and a novel mechanism to control Gal-9 through IFN-? induction. PMID:25008927

  9. Nicotine-induced upregulation of native neuronal nicotinic receptors is caused by multiple mechanisms

    PubMed Central

    Govind, Anitha P.; Walsh, Heather; Green, William N.

    2012-01-01

    Nicotine causes changes in brain nicotinic acetylcholine receptors (nAChRs) during smoking that initiate addiction. Nicotine-induced upregulation is the long-lasting increase in nAChR radio-ligand binding sites in brain resulting from exposure. The mechanisms causing upregulation are not established. Many different mechanisms have been reported with the assumption that there is a single, underlying cause. Using live cortical neurons, we examined for the first time how exposure and withdrawal of nicotine shape the kinetics of native ?4?2-containing nAChR upregulation in real time. Upregulation kinetics demonstrate that at least two different mechanisms underlie this phenomenon. First, a transient upregulation occurs that rapidly reverses, faster than nAChR degradation, and corresponds to nAChR conformational changes as assayed by conformational-dependent, subunit-specific antibodies. Second, a long-lasting process occurs correlating with increases in nAChR numbers caused by decreased proteasomal subunit degradation. Previous radio-ligand binding measurements to brain tissue have measured the second process and largely missed the first. We conclude that nicotine-induced upregulation is composed of multiple processes occurring at different rates with different underlying causes. PMID:22323734

  10. Bilirubin inhibits the up-regulation of inducible nitric oxide synthase by scavenging reactive oxygen species generated by the toll-like receptor 4-dependent activation of NADPH oxidase

    PubMed Central

    Idelman, Gila; Smith, Darcey L.H.; Zucker, Stephen D.

    2015-01-01

    It has been previously shown that bilirubin prevents the up-regulation of inducible nitric oxide synthase (iNOS) in response to LPS. The present study examines whether this effect is exerted through modulation of Toll-Like Receptor-4 (TLR4) signaling. LPS-stimulated iNOS and NADPH oxidase (Nox) activity in RAW 264.7 murine macrophages was assessed by measuring cellular nitrate and superoxide (O2?) production, respectively. The generation of both nitrate and O2? in response to LPS was suppressed by TLR4 inhibitors, indicating that activation of iNOS and Nox is TLR4-dependent. While treatment with superoxide dismutase (SOD) and bilirubin effectively abolished LPS-mediated O2? production, hydrogen peroxide and nitrate release were inhibited by bilirubin and PEG-catalase, but not SOD, supporting that iNOS activation is primarily dependent upon intracellular H2O2. LPS treatment increased nuclear translocation of the redox-sensitive transcription factor Hypoxia Inducible Factor-1? (HIF-1?), an effect that was abolished by bilirubin. Cells transfected with murine iNOS reporter constructs in which the HIF-1?-specific hypoxia response element was disrupted exhibited a blunted response to LPS, supporting that HIF-1? mediates Nox-dependent iNOS expression. Bilirubin, but not SOD, blocked the cellular production of interferon-?, while interleukin-6 production remained unaffected. These data support that bilirubin inhibits the TLR4-mediated up-regulation of iNOS by preventing activation of HIF-1? through scavenging of Nox-derived reactive oxygen species. Bilirubin also suppresses interferon-? release via a ROS-independent mechanism. These findings characterize potential mechanisms for the anti-inflammatory effects of bilirubin. PMID:26163808

  11. Upregulation of NLRP3 Inflammasome in the Tears and Ocular Surface of Dry Eye Patients

    PubMed Central

    Wu, Jihong; Chen, Ling; Wang, Yan

    2015-01-01

    Purpose To evaluate the mRNA and protein expressions of NLRP3 inflammasome and its downstream inflammatory factors in human dry eye. Methods We recruited 54 patients with Sjögren’s syndrome dry eye (SSDE), 50 patients with non-Sjögren’s syndrome dry eye (NSSDE), and 46 healthy controls. Tear film breakup time (TBUT), Schirmer I test, and fluorescein staining (FL) were performed on all subjects. Tear samples were obtained to analyze the inflammatory cytokine levels of IL-1? and IL-18 via enzyme-linked immunosorbent (ELISA). Conjunctival impression cytology (CIC) specimens were collected to detect the mRNA expression of NLRP3, caspase-1, IL-1?, and IL-18 using quantitative RT-PCR, and the protein expression of NLRP3 and caspase-1 by Western blotting. Results NLRP3 mRNA expression showed higher levels in both dry eye groups compared with controls, with a comparably significant elevation in the SSDE group (relative 2.47-fold upregulation, p<0.05). NLRP3 protein expression was also increased in SSDE group (relative1.94-fold upregulation) compared with the controls. mRNA expression of caspase-1 was significantly upregulated in both SSDE (relative 1.44-fold upregulation, p<0.05) and NSSDE (relative 1.32-fold upregulation, p<0.05). Procaspase-1 protein level was increased in SSDE (relative 1.84-fold upregulation) and NSSDE (relative 1.12-fold upregulation) versus controls; and caspase-1 protein expression was also increased in SSDE (relative 1.49-fold upregulation) and NSSDE (relative 1.17-fold upregulation) compared with the controls. The patients with SSDE and NSSDE had higher IL-1? and IL-18 mRNA values and protein expressions than the controls did. The relative mRNA expression of IL-1? upregulated 3.59-fold (p<0.001) in SSDE and 2.13-fold (p<0.01) in NSSDE compared with the controls. IL-1? protein level also showed significant upregulation in SSDE (p=0.01; vs. controls groups). IL-18 mRNA expression levels were significantly upregulated in the SSDE (relative 2.97-fold upregulation, p=0.001) and NSSDE (relative 2.05-fold upregulation, p=0.001) groups compared with the controls; tear IL-18 concentrations were also significantly increased in the SSDE (p<0.001) and NSSDE (p<0.05) groups. Conclusions In the current study, we found that mRNA and protein expressions of NLRP3 inflammasome were upregulated in human dry eyes, especially in SSDE; the downstream inflammatory factors caspase-1, IL-1?, and IL-18 were also elevated in dry eye patients. These observations suggest the involvement of NLRP3 inflammasome in the onset and development of the inflammation in dry eye. PMID:25962072

  12. Crystal structure of the catalase-peroxidase KatG W78F mutant from Synechococcus elongatus PCC7942 in complex with the antitubercular pro-drug isoniazid.

    PubMed

    Kamachi, Saori; Hirabayashi, Kei; Tamoi, Masahiro; Shigeoka, Shigeru; Tada, Toshiji; Wada, Kei

    2015-01-01

    Isoniazid (INH) is a pro-drug that has been extensively used to treat tuberculosis. INH is activated by the heme enzyme catalase-peroxidase (KatG), but the mechanism of the activation is poorly understood, in part because the INH binding site has not been clearly established. Here, we observed that a single-residue mutation of KatG from Synechococcus elongatus PCC7942 (SeKatG), W78F, enhances INH activation. The crystal structure of INH-bound KatG-W78F revealed that INH binds to the heme pocket. The results of a thermal-shift assay implied that the flexibility of the SeKatG molecule is increased by the W78F mutation, allowing the INH molecule to easily invade the heme pocket through the access channel on the ?-edge side of the heme. PMID:25479089

  13. The up-regulation of hepatic acyl-CoA oxidase and cytochrome P450 4A1 mRNA expression by dietary oxidized frying oil is comparable between male and female rats.

    PubMed

    Chao, Pei-Min; Hsu, Shan-Ching; Lin, Fu-Jung; Li, Yi-Jen; Huang, Ching-Jang

    2004-03-01

    We previously demonstrated that oxidized frying oil (OFO) activates peroxisome proliferator-activated receptor alpha (PPARalpha) and up-regulates hepatic acyl-CoA oxidase (ACO) and cytochrome P450 4A1 (CYP4A1) genes in male rats. As female rats were shown to be less responsive to some peroxisome proliferators (PP), this study compared the expression of a few PPARalpha target genes in male and female rats fed diets containing OFO. Male and female rats were fed a diet containing 20 g/100 g OFO (O diet) or fresh soybean oil (F diet) for 6 wk. Both male and female rats fed the O diet showed significantly higher liver weight, hepatic ACO and catalase activities, CYP4A protein, and expression of ACO and CYP4A1 mRNA (P < 0.05) compared with their control groups. The mRNA expression of two other PPARalpha target genes, FA-binding protein and HMG-CoA synthase, were marginally increased by dietary OFO (P = 0.0669 and 0.0521, respectively). Female rats fed the O diet had significantly lower CYP4A protein than male rats fed the same diet. The remaining OFO-induced effects were not significantly different between male and female rats fed the O diet. These results indicate that dietary OFO, unlike clofibrate or other PP, had minimal sexual dimorphic effect on the induction of hepatic PPARalpha target gene expression. PMID:15233401

  14. [Colorimetric determination of sulfite in "kanpyo" (dried gourd shavings) and "konnyakuseiko" (devil's-tongue fine powder) using sulfite oxidase and catalase].

    PubMed

    Aoki, Kazuko; Ueno, Seiichi; Ishizaki, Mutsuo

    2002-06-01

    A simple and convenient method for colorimetric determination of sulfite in foods based on its conversion to formaldehyde with sulfite oxidase and catalase was developed. Sulfite in a sample was extracted with water and then diluted with methanol. One mL of sample solution containing about 5-10 micrograms of sulfite was taken into a test tube with a ground-glass stopper, and 3 mL of 0.04 mol/L borate buffer (pH 8.7), 1 mL of 0.4% 3-methyl-2-benzothiazolinone hydrazone (MBTH) solution, 2,000 units of catalase solution and 1.0 units of sulfite oxidase were added. The mixture was incubated for 35 minutes at 37 degrees C. Then 0.15 mL of 1 mol/L hydrochloric acid and 5 mL of 0.2% iron(III) nitrate solution were added. The reaction mixture was transferred to a measuring flask after standing for 5 minutes at room temperature, and diluted to 20 mL with methanol. The absorbance of this solution was measured using a spectrophotometer at the wavelength of 635 nm. The calibration curve prepared with sodium sulfite showed linearity between 0 to 16 micrograms/mL as sulfur dioxide. The recoveries of sulfite in "Kanpyo" (dried gourd shavings) and "Konnyaku-seiko" (devil's-tongue fine powder) by the proposed method were 97-104%, and the coefficients of variation were below 6%. The sulfite values in these foods determined by the proposed method were reasonably consistent with those obtained by the bubbling distillation-alkaline titration method. PMID:12238155

  15. Iron, copper, and manganese complexes with in vitro superoxide dismutase and/or catalase activities that keep Saccharomyces cerevisiae cells alive under severe oxidative stress.

    PubMed

    Ribeiro, Thales P; Fernandes, Christiane; Melo, Karen V; Ferreira, Sarah S; Lessa, Josane A; Franco, Roberto W A; Schenk, Gerhard; Pereira, Marcos D; Horn, Adolfo

    2015-03-01

    Due to their aerobic lifestyle, eukaryotic organisms have evolved different strategies to overcome oxidative stress. The recruitment of some specific metalloenzymes such as superoxide dismutases (SODs) and catalases (CATs) is of great importance for eliminating harmful reactive oxygen species (hydrogen peroxide and superoxide anion). Using the ligand HPClNOL {1-[bis(pyridin-2-ylmethyl)amino]-3-chloropropan-2-ol}, we have synthesized three coordination compounds containing iron(III), copper(II), and manganese(II) ions, which are also present in the active site of the above-noted metalloenzymes. These compounds were evaluated as SOD and CAT mimetics. The manganese and iron compounds showed both SOD and CAT activities, while copper showed only SOD activity. The copper and manganese in vitro SOD activities are very similar (IC50~0.4 ?mol dm(-3)) and about 70-fold higher than those of iron. The manganese compound showed CAT activity higher than that of the iron species. Analyzing their capacity to protect Saccharomyces cerevisiae cells against oxidative stress (H2O2 and the O2(•-) radical), we observed that all compounds act as antioxidants, increasing the resistance of yeast cells mainly due to a reduction of lipid oxidation. Especially for the iron compound, the data indicate complete protection when wild-type cells were exposed to H2O2 or O2(•-) species. Interestingly, these compounds also compensate for both superoxide dismutase and catalase deficiencies; their antioxidant activity is metal ion dependent, in the order iron(III)>copper(II)>manganese(II). The protection mechanism employed by the complexes proved to be independent of the activation of transcription factors (such as Yap1, Hsf1, Msn2/Msn4) and protein synthesis. There is no direct relation between the in vitro and the in vivo antioxidant activities. PMID:25511255

  16. Peroxiredoxin 2, glutathione peroxidase, and catalase in the cytosol and membrane of erythrocytes under H2O2-induced oxidative stress.

    PubMed

    Rocha, S; Gomes, D; Lima, M; Bronze-da-Rocha, E; Santos-Silva, A

    2015-08-01

    Erythrocytes are continuously exposed to risk of oxidative injury due to oxidant oxygen species. To prevent damage, they have antioxidant agents namely, catalase (Cat), glutathione peroxidase (GPx), and peroxiredoxin 2 (Prx2). Our aim was to contribute to a better understanding of the interplay between Prx2, Cat, and GPx under H2O2-induced oxidative stress, by studying their changes in the red blood cell cytosol and membrane, in different conditions. These three enzymes were quantified by immunoblotting. Malondialdehyde, that is, lipoperoxidation (LPO) in the erythrocyte membrane, and membrane-bound hemoglobin (MBH) were evaluated, as markers of oxidative stress. We also studied the erythrocyte membrane protein profile, to estimate how oxidative stress affects the membrane protein structure. We showed that under increasing H2O2 concentrations, inhibition of the three enzymes with or without metHb formation lead to the binding of Prx2 and GPx (but not Cat) to the erythrocyte membrane. Prx2 was detected mainly in its oxidized form and the linkage of metHb to the membrane seems to compete with the binding of Prx2. Catalase played a major role in protecting erythrocytes from high exogenous flux of H2O2, since whenever Cat was active there were no significant changes in any of the studied parameters. When only Cat was inhibited, Prx2 and GPx were unable to prevent H2O2-induced oxidative stress resulting in increasing MBH and membrane LPO. Additionally, the inhibition of one or more of these enzymes induced changes in the anchor/linker proteins of the junctional complexes of the membrane cytoskeleton-lipid bilayer, which might lead to membrane destabilization. PMID:25786472

  17. Mechanisms of Hypoxic Up-Regulation of Versican Gene Expression in Macrophages

    PubMed Central

    Sotoodehnejadnematalahi, Fattah; Staples, Karl J.; Chrysanthou, Elvina; Pearson, Helen; Ziegler-Heitbrock, Loems; Burke, Bernard

    2015-01-01

    Hypoxia is a hallmark of many pathological tissues. Macrophages accumulate in hypoxic sites and up-regulate a range of hypoxia-inducible genes. The matrix proteoglycan versican has been identified as one such gene, but the mechanisms responsible for hypoxic induction are not fully characterised. Here we investigate the up-regulation of versican by hypoxia in primary human monocyte-derived macrophages (HMDM), and, intriguingly, show that versican mRNA is up-regulated much more highly (>600 fold) by long term hypoxia (5 days) than by 1 day of hypoxia (48 fold). We report that versican mRNA decay rates are not affected by hypoxia, demonstrating that hypoxic induction of versican mRNA is mediated by increased transcription. Deletion analysis of the promoter identified two regions required for high level promoter activity of luciferase reporter constructs in human macrophages. The hypoxia-inducible transcription factor HIF-1 has previously been implicated as a key potential regulator of versican expression in hypoxia, however our data suggest that HIF-1 up-regulation is unlikely to be principally responsible for the high levels of induction observed in HMDM. Treatment of HMDM with two distinct specific inhibitors of Phosphoinositide 3-kinase (PI3K), LY290042 and wortmannin, significantly reduced induction of versican mRNA by hypoxia and provides evidence of a role for PI3K in hypoxic up-regulation of versican expression. PMID:26057378

  18. Granulocyte colony stimulating factor induces lipopolysaccharide (LPS) sensitization via upregulation of LPS binding protein in rat.

    PubMed

    Fang, Haoshu; Liu, Anding; Sun, Jian; Kitz, Alexandra; Dirsch, Olaf; Dahmen, Uta

    2013-01-01

    Liver is the main organ for lipopolysaccharide (LPS) clearance. Sensitization to LPS is associated with the upregulation of LPS-binding protein (LBP) in animal models. Therefore, we hypothesized that LBP could induce LPS sensitization through enhancing hepatic uptake of LPS. In this study, we examined the role of LBP in pathogenesis of LPS induced systemic inflammatory response syndrome (SIRS). LBP expression was upregulated after granulocyte colony stimulating (G-CSF) pretreatment. The effect of LBP was further confirmed by blockade of LBP using LBP blocking peptide--LBPK95A. After G-CSF pretreatment, upregulation of LBP was observed in bone marrow cells and liver. The G-CSF induced LBP upregulation caused LPS hypersensitization in rats as indicated by higher mortality and severer liver damage. Of note, LBP blockade increased the survival rate and attenuated the liver injury. The LBP induced LPS hypersensitization was associated with increased hepatic uptake of LPS and augmented hepatic expression of LPS receptors, such as toll-like receptor (TLR)-4. Furthermore, LBP mediated early neutrophil infiltration, which led to increased monocyte recruitment in liver after LPS administration. In conclusion, G-CSF induced LBP expression could serve as a new model for investigation of LPS sensitization. We demonstrated the crucial role of LBP upregulation in pathogenesis of LPS induced SIRS. PMID:23437199

  19. Granulocyte Colony Stimulating Factor Induces Lipopolysaccharide (LPS) Sensitization via Upregulation of LPS Binding Protein in Rat

    PubMed Central

    Fang, Haoshu; Liu, Anding; Sun, Jian; Kitz, Alexandra; Dirsch, Olaf; Dahmen, Uta

    2013-01-01

    Liver is the main organ for lipopolysaccharide (LPS) clearance. Sensitization to LPS is associated with the upregulation of LPS-binding protein (LBP) in animal models. Therefore, we hypothesized that LBP could induce LPS sensitization through enhancing hepatic uptake of LPS. In this study, we examined the role of LBP in pathogenesis of LPS induced systemic inflammatory response syndrome (SIRS). LBP expression was upregulated after granulocyte colony stimulating (G-CSF) pretreatment. The effect of LBP was further confirmed by blockade of LBP using LBP blocking peptide – LBPK95A. After G-CSF pretreatment, upregulation of LBP was observed in bone marrow cells and liver. The G-CSF induced LBP upregulation caused LPS hypersensitization in rats as indicated by higher mortality and severer liver damage. Of note, LBP blockade increased the survival rate and attenuated the liver injury. The LBP induced LPS hypersensitization was associated with increased hepatic uptake of LPS and augmented hepatic expression of LPS receptors, such as toll-like receptor (TLR)-4. Furthermore, LBP mediated early neutrophil infiltration, which led to increased monocyte recruitment in liver after LPS administration. In conclusion, G-CSF induced LBP expression could serve as a new model for investigation of LPS sensitization. We demonstrated the crucial role of LBP upregulation in pathogenesis of LPS induced SIRS. PMID:23437199

  20. Hypoxia up-regulates SERPINB3 through HIF-2? in human liver cancer cells

    PubMed Central

    Paternostro, Claudia; Biasiolo, Alessandra; Colombatto, Sebastiano; Cambieri, Irene; Quarta, Santina; Novo, Erica; Morello, Elisabetta; Villano, Gianmarco; Fasolato, Silvano; Musso, Tiziana; David, Ezio; Tusa, Ignazia; Rovida, Elisabetta; Autelli, Riccardo; Smedile, Antonina; Cillo, Umberto; Pontisso, Patrizia; Parola, Maurizio

    2015-01-01

    SERPINB3 is a cysteine-proteases inhibitor up-regulated in a significant number of cirrhotic patients carrying hepatocellular carcinoma (HCC) and recently proposed as a prognostic marker for HCC early recurrence. SERPINB3 has been reported to stimulate proliferation, inhibit apoptosis and, similar to what reported for hypoxia, to trigger epithelial-to-mesenchymal transition (EMT) and increased invasiveness in liver cancer cells. This study has investigated whether SERPINB3 expression is regulated by hypoxia-related mechanisms in liver cancer cells. Exposure of HepG2 and Huh7 cells to hypoxia up-regulated SERPINB3 transcription, protein synthesis and release in the extracellular medium. Hypoxia-dependent SERPINB3 up-regulation was selective (no change detected for SERPINB4) and operated through hypoxia inducible factor (HIF)-2? (not HIF-1?) binding to SERPINB3 promoter, as confirmed by chromatin immuno-precipitation assay and silencing experiments employing specific siRNAs. HIF-2?-mediated SERPINB3 up-regulation under hypoxic conditions required intracellular generation of ROS. Immuno-histochemistry (IHC) and transcript analysis, performed in human HCC specimens, revealed co-localization of the two proteins in liver cancer cells and the existence of a positive correlation between HIF-2? and SERPINB3 transcript levels, respectively. Hypoxia, through HIF-2?-dependent and redox-sensitive mechanisms, up-regulates the transcription, synthesis and release of SERPINB3, a molecule with a high oncogenic potential. PMID:25544768

  1. COMBINED BIOCHEMICAL AND MORPHOLOGICAL STUDY OF PARTICULATE FRACTIONS FROM RAT LIVER: Analysis of Preparations Enriched in Lysosomes or in Particles Containing Urate Oxidase, D-Amino Acid Oxidase, and Catalase

    Microsoft Academic Search

    PIERRE BAUDHUIN; HENRI BEAUFAY

    1965-01-01

    Six particulate preparations isolated from rat liver under different experimental condi- tions were analyzed biochemically and examined in the electron microscope. The results confirm the lysosomal nature of the pericanalicular dense bodies and demonstrate that the microbodics arc the bearers of urate oxidase, catalase, and D-amino acid oxidasc. Catalasc, representing a major component of the particles, and D-amino acid oxidase

  2. Expression of the Abca-Subfamily of Genes in Abcc6-/- Mice – Upregulation of Abca4

    PubMed Central

    Li, Qiaoli; Uitto, Jouni

    2011-01-01

    Pseudoxanthoma elasticum (PXE), a heritable multi-system disorder, is caused by mutations in the ABCC6 gene primarily expressed in the liver. Recent analysis of cultured fibroblasts from patients with PXE has suggested compensatory alterations in the expression of the ABCA-subfamily of genes. We have now determined by quantitative RT-PCR the level of expression of Abca-family of genes in a mouse model of PXE developed by targeted ablation of Abcc6. The results indicated variable levels of mRNA for different Abca genes in the liver, however, only one of them, Abca4, was significantly, ~6.5-fold, upregulated in the Abcc6-/- mice in comparison to wild-type mice. In the same mice, Abca4 was not upregulated in the eyes or the kidney, suggesting that the upregulation of Abca4 in the liver is a tissue-specific compensatory consequence of the “knock-out” of Abcc6. PMID:21435020

  3. Mu opioid receptor up-regulation and participation in excitability of hippocampal pyramidal cell electrophysiology

    SciTech Connect

    Moudy, A.M.

    1988-01-01

    Chronic administration of opiate antagonists to rats results in up-regulation of their brain opioid receptors. Using subcellular fractionation techniques, brain opioid receptors were resolved into two membrane populations, one associated with synaptic plasma membranes (SPM) and the other enriched in smooth endoplasmic reticulum and Golgi (microsomes). This study addressed in part the question of whether an antagonist induces up-regulation uniformly in these two populations. Rats were administered naltrexone by subcutaneously implanted osmotic minipumps. Forebrain mu receptor levels were determined by homologous displacement of ({sup 3}H)D-ala{sup 2}-mePhe{sup 4}-gly-ol{sup 5}-enkephalin (DAGO) followed by computer estimation of binding parameters. Receptor levels in crude membranes rose 77% after treatment. Microsomes displayed a 92% increase, a two-fold greater change than in SPMs (51%). These results establish that naltrexone induces up-regulation of both membrane populations; and that microsomal and SPM receptors represent discrete populations of intracellular and cell surface sites, respectively. Binding experiments on isolated hippocampi also demonstrated up-regulation (71%) of mu receptors. To demonstrate up-regulation of opioid receptors electrophysiologically, hippocampal slices were prepared from rats which had been chronically treated with naltrexone. After superfusion with DAGO, these slices showed a 42% greater population spike output than controls in response to the same EPSP input. Hippocampi from animals treated for two weeks showed an additional increase in sensitivity. The results support a disinhibitory role for opioids in pyramidal cell hyper-excitability. More importantly, they demonstrate a significant physiological correlate to opioid receptor up-regulation.

  4. Involvement of heat shock factor 1 in statin-induced transcriptional upregulation of endothelial thrombomodulin

    PubMed Central

    Fu, Qiang; Wang, Junru; Boerma, Marjan; Berbée, Maaike; Qiu, Xiaohua; Fink, Louis M.; Hauer-Jensen, Martin

    2008-01-01

    Statins upregulate endothelial thrombomodulin (TM) by mechanisms that involve members of the Kruppel-like factor (KLF) family. While KLFs are unequivocally implicated in this process experimental evidence points to additional mechanisms. Deletion/mutation analysis of reporter constructs was used to demonstrate that mutation of the SP1/KLF element in the TM promoter only partially abolishes statin-induced TM upregulation whereas simultaneous mutation of relevant heat shock elements (HSEs) and SP1/KLF element completely prevents statin-induced TM upregulation, thus demonstrating a role for heat shock factors (HSFs). We further identified the pathway by which statins increase binding of HSF1 to HSEs in the TM promoter. Specifically, statins caused NO-dependent dissociation of HSF1 from heat shock protein 90 (HSP90), nuclear translocation of HSF1, and binding to HSEs in the TM promoter. Statins also decreased nuclear content of the HSF1 chaperone 14-3-3?. In addition to reducing TM upregulation, inhibition of HSF1 reduced statin-induced upregulation of tissue plasminogen activator (tPA), whereas, downregulation of thrombomospondin (TSP-1), plasminogen activator inhibitor 1 (PAI-1), or connective tissue growth factor (CTGF) was unaffected. Knockdown of 14-3-3? or inhibition of HSF1 phosphorylation enhanced the effect of statins on TM and tPA, but did not influence TSP-1, PAI-1, or CTGF. These data demonstrate that HSF1 is involved in statin-induced regulation of TM. They also suggest that analogous mechanisms may apply to genes that are upregulated by statins, but not to downregulated genes. These results may have broad implications and suggest the use of heat shock protein modulators to selectively regulate pleiotropic statin effects. PMID:18599869

  5. Pim kinases are upregulated during Epstein-Barr virus infection and enhance EBNA2 activity

    SciTech Connect

    Rainio, Eeva-Marja [Turku Centre for Biotechnology, University of Turku/Abo Akademi University, Tykistoekatu 6B, 20520 Turku (Finland); Turku Graduate School of Biomedical Sciences, 20520 Turku (Finland); Ahlfors, Helena [Turku Centre for Biotechnology, University of Turku/Abo Akademi University, Tykistoekatu 6B, 20520 Turku (Finland); Carter, Kara L. [Department of Medicine and Microbiology, Harvard Medical School, Boston, MA 02115 (United States); Department of Molecular Genetics, Harvard Medical School, Boston, MA 02115 (United States); Channing Laboratory, Brigham and Women's Hospital, Boston, MA 02115 (United States); Ruuska, Marja [Turku Centre for Biotechnology, University of Turku/Abo Akademi University, Tykistoekatu 6B, 20520 Turku (Finland); Matikainen, Sampsa [Turku Centre for Biotechnology, University of Turku/Abo Akademi University, Tykistoekatu 6B, 20520 Turku (Finland); Department of Microbiology, National Public Health Institute, Mannerheimintie 166, 00300 Helsinki (Finland); Kieff, Elliott [Department of Medicine and Microbiology, Harvard Medical School, Boston, MA 02115 (United States); Department of Molecular Genetics, Harvard Medical School, Boston, MA 02115 (United States); Channing Laboratory, Brigham and Women's Hospital, Boston, MA 02115 (United States); Koskinen, Paeivi J. [Turku Centre for Biotechnology, University of Turku/Abo Akademi University, Tykistoekatu 6B, 20520 Turku (Finland)]. E-mail: paivi.koskinen@btk.fi

    2005-03-15

    Latent Epstein-Barr virus (EBV) infection is strongly associated with B-cell proliferative diseases such as Burkitt's lymphoma. Here we show that the oncogenic serine/threonine kinases Pim-1 and Pim-2 enhance the activity of the viral transcriptional activator EBNA2. During EBV infection of primary B-lymphocytes, the mRNA expression levels of pim genes, especially of pim-2, are upregulated and remain elevated in latently infected B-cell lines. Thus, EBV-induced upregulation of Pim kinases and Pim-stimulated EBNA2 transcriptional activity may contribute to the ability of EBV to immortalize B-cells and predispose them to malignant growth.

  6. Expression, purification, crystallization and preliminary X-ray analysis of the Met244Ala variant of catalase–peroxidase (KatG) from the haloarchaeon Haloarcula marismortui

    SciTech Connect

    Ten-i, Tomomi; Kumasaka, Takashi [Department of Life Science, Graduate School of Bioscience and Biotechnology, Tokyo Institute of Technology, 4259-B-10 Nagatsuta, Midori-ku, Yokohama 226-8501 (Japan); Higuchi, Wataru; Tanaka, Satoru; Yoshimatsu, Katsuhiko; Fujiwara, Taketomo [Department of Biological Sciences, Faculty of Science, Shizuoka University, 836 Ohya, Suruga-ku, Shizuoka 422-8529 (Japan); Sato, Takao, E-mail: tsatoh@bio.titech.ac.jp [Department of Life Science, Graduate School of Bioscience and Biotechnology, Tokyo Institute of Technology, 4259-B-10 Nagatsuta, Midori-ku, Yokohama 226-8501 (Japan)

    2007-11-01

    The Met244Ala variant of the H. marismortui KatG enzyme was expressed in haloarchaeal host cells and purified to homogeneity. The variant was crystallized using the hanging-drop vapour-diffusion method with ammonium sulfate and NaCl as precipitants. The reddish-brown rod-shaped crystals obtained belong to the monoclinic space group C2, with unit-cell parameters a = 315.24, b = 81.04, c = 74.77 Å, ? = 99.81°. The covalent modification of the side chains of Trp95, Tyr218 and Met244 within the active site of Haloarcula marismortui catalase–peroxidase (KatG) appears to be common to all KatGs and has been demonstrated to be particularly significant for its bifunctionality [Smulevich et al. (2006 ?), J. Inorg. Biochem.100, 568–585; Jakopitsch, Kolarich et al. (2003 ?), FEBS Lett.552, 135–140; Jakopitsch, Auer et al. (2003 ?), J. Biol. Chem.278, 20185–20191; Jakopitsch et al. (2004 ?), J. Biol. Chem.279, 46082–46095; Regelsberger et al. (2001 ?), Biochem. Soc. Trans.29, 99–105; Ghiladi, Knudsen et al. (2005 ?), J. Biol. Chem.280, 22651–22663; Ghiladi, Medzihradzky et al. (2005 ?), Biochemistry, 44, 15093–15105]. The Met244Ala variant of the H. marismortui KatG enzyme was expressed in haloarchaeal host cells and purified to homogeneity. The variant showed a complete loss of catalase activity, whereas the peroxidase activity of this mutant was highly enhanced owing to an increase in its affinity for the peroxidatic substrate. The variant was crystallized using the hanging-drop vapour-diffusion method with ammonium sulfate and NaCl as precipitants. The reddish-brown rod-shaped crystals obtained belong to the monoclinic space group C2, with unit-cell parameters a = 315.24, b = 81.04, c = 74.77 Å, ? = 99.81°. A crystal frozen using lithium sulfate as the cryoprotectant diffracted to beyond 2.0 Å resolution. Preliminary X-ray analysis suggests the presence of a dimer in the asymmetric unit.

  7. Expression Analysis of Up-Regulated Genes Responding to Plumbagin in Escherichia coli

    Microsoft Academic Search

    Jenn-Wei Chen; Chang-Ming Sun; Wei-Lun Sheng; Yu-Chen Wang; Wan-Jr Syu

    2006-01-01

    Plumbagin is found in many medicinal plants and has been reported to have antimicrobial activities. We examined the molecular responses of Escherichia coli to plumbagin by using a proteomic approach to search for bacterial genes up-regulated by the drug. The protein profile obtained was compared with that of E. coli without the plumbagin treatment. Subsequent analyses of the induced proteins

  8. Mitochondrial Dihydrolipoamide Dehydrogenase Is Upregulated in Response to Intermittent Hypoxic Preconditioning

    PubMed Central

    Li, Rongrong; Luo, Xiaoting; Wu, Jinzi; Thangthaeng, Nopporn; Jung, Marianna E.; Jing, Siqun; Li, Linya; Ellis, Dorette Z.; Liu, Li; Ding, Zhengnian; Forster, Michael J.; Yan, Liang-Jun

    2015-01-01

    Intermittent hypoxia preconditioning (IHP) has been shown to protect neurons against ischemic stroke injury. Studying how proteins respond to IHP may identify targets that can help fight stroke. The objective of the present study was to investigate whether mitochondrial dihydrolipoamide dehydrogenase (DLDH) would respond to IHP and if so, whether such a response could be linked to neuroprotection in ischemic stroke injury. To do this, we subjected male rats to IHP for 20 days and measured the content and activity of DLDH as well as the three ?-keto acid dehydrogenase complexes that contain DLDH. We also measured mitochondrial electron transport chain enzyme activities. Results show that DLDH content was indeed upregulated by IHP and this upregulation did not alter the activities of the three ?-keto acid dehydrogenase complexes. Results also show that the activities of the five mitochondrial complexes (I-V) were not altered either by IHP. To investigate whether IHP-induced DLDH upregulation is linked to neuroprotection against ischemic stroke injury, we subjected both DLDH deficient mouse and DLDH transgenic mouse to stroke surgery followed by measurement of brain infarction volume. Results indicate that while mouse deficient in DLDH had exacerbated brain injury after stroke, mouse overexpressing human DLDH also showed increased brain injury after stroke. Therefore, the physiological significance of IHP-induced DLDH upregulation remains to be further investigated.

  9. CD84 is markedly up-regulated in Kawasaki disease arteriopathy

    PubMed Central

    Reindel, R; Bischof, J; Kim, K-Y A; Orenstein, J M; Soares, M B; Baker, S C; Shulman, S T; Perlman, E J; Lingen, M W; Pink, A J; Trevenen, C; Rowley, A H

    2014-01-01

    The major goals of Kawasaki disease (KD) therapy are to reduce inflammation and prevent thrombosis in the coronary arteries (CA), but some children do not respond to currently available non-specific therapies. New treatments have been difficult to develop because the molecular pathogenesis is unknown. In order to identify dysregulated gene expression in KD CA, we performed high-throughput RNA sequencing on KD and control CA, validated potentially dysregulated genes by real-time reverse transcription–polymerase chain reaction (RT–PCR) and localized protein expression by immunohistochemistry. Signalling lymphocyte activation molecule CD84 was up-regulated 16-fold (P < 0·01) in acute KD CA (within 2 months of onset) and 32-fold (P < 0·01) in chronic CA (5 months to years after onset). CD84 was localized to inflammatory cells in KD tissues. Genes associated with cellular proliferation, motility and survival were also up-regulated in KD CA, and immune activation molecules MX2 and SP140 were up-regulated in chronic KD. CD84, which facilitates immune responses and stabilizes platelet aggregates, is markedly up-regulated in KD CA in patients with acute and chronic arterial disease. We provide the first molecular evidence of dysregulated inflammatory responses persisting for months to years in CA significantly damaged by KD. PMID:24635044

  10. Endothelial adherens junctions control tight junctions by VE-cadherin-mediated upregulation of claudin-5

    Microsoft Academic Search

    Andrea Taddei; Costanza Giampietro; Annarita Conti; Fabrizio Orsenigo; Ferruccio Breviario; Valentina Pirazzoli; Michael Potente; Christopher Daly; Stefanie Dimmeler; Elisabetta Dejana

    2008-01-01

    Intercellular junctions mediate adhesion and communication between adjoining cells. Although formed by different molecules, tight junctions (TJs) and adherens junctions (AJs) are functionally and structurally linked, but the signalling pathways behind this interaction are unknown. Here we describe a cell-specific mechanism of crosstalk between these two types of structure. We show that endothelial VE-cadherin at AJs upregulates the gene encoding

  11. Upregulation of Heat Shock Proteins Rescues Motoneurones from Axotomy-Induced Cell Death in Neonatal Rats

    E-print Network

    Burnstock, Geoffrey

    Upregulation of Heat Shock Proteins Rescues Motoneurones from Axotomy-Induced Cell Death in Neonatal Rats B. Kalmar,*, G. Burnstock, G. Vrbova´,§ R. Urbanics, P. Csermely,,¶ and L. Greensmith*,1 death. © 2002 Elsevier Science (USA) INTRODUCTION Heat shock proteins (hsps) are widely regarded

  12. Upregulation of cathepsin S in psoriatic keratinocytes Alexander Scho nefu1

    E-print Network

    Lübbert, Hermann

    skin biopsies, i.e. atopic dermatitis, actinic keratosis and psoriasis, CATS staining is strongly increased in the dermis. But only in psoriasis, CATS- immunostaining is also detectable in keratinocytes. We ­ psoriasis ­ T-cell Please cite this paper as: Upregulation of cathepsin S in psoriatic keratinocytes

  13. Expression of a GALACTINOL SYNTHASE Gene in Tomato Seeds Is Up-Regulated before Maturation

    E-print Network

    Bradford, Kent

    Expression of a GALACTINOL SYNTHASE Gene in Tomato Seeds Is Up-Regulated before Maturation of environmental stresses on plants. In seeds, proposed roles for RFOs include protecting cellular integrity during) seeds, and its expression was characterized in tomato seeds and seedlings. GOLS (LeGOLS-1) m

  14. Upregulation of pirin expression by chronic cigarette smoking is associated with bronchial epithelial cell apoptosis

    Microsoft Academic Search

    Brian D Gelbman; Adriana Heguy; Timothy P O'Connor; Joseph Zabner; Ronald G Crystal

    2007-01-01

    BACKGROUND: Cigarette smoke disrupts the protective barrier established by the airway epithelium through direct damage to the epithelial cells, leading to cell death. Since the morphology of the airway epithelium of smokers does not typically demonstrate necrosis, the most likely mechanism for epithelial cell death in response to cigarette smoke is apoptosis. We hypothesized that cigarette smoke directly up-regulates expression

  15. Cotton Benzoquinone Reductase: Up-regulation During Early Cotton Fiber Developement

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Benzoquinone reductase (BR; EC 1.6.5.7) is an enzyme that catalyzes the bivalent redox reactions of quinones without the production of free radical intermediates. Using 2-D PAGE comparisons, two proteins were found to be up-regulated in wild-type cotton ovules during the fiber initiation stage but ...

  16. Executive functions and the down-regulation and up-regulation of emotion

    Microsoft Academic Search

    Anett Gyurak; Madeleine S. Goodkind; Joel H. Kramer; Bruce L. Miller; Robert W. Levenson

    2012-01-01

    This study examined the relationship between individual differences in executive functions (EF; assessed by measures of working memory, Stroop, trail making, and verbal fluency) and ability to down-regulate and up-regulate responses to emotionally evocative film clips. To ensure a wide range of EF, 48 participants with diverse neurodegenerative disorders and 21 older neurologically normal ageing participants were included. Participants were

  17. Involvement of upregulation of DEPDC1 (DEP domain containing 1) in bladder carcinogenesis

    Microsoft Academic Search

    M Kanehira; Y Harada; R Takata; T Shuin; T Miki; T Fujioka; Y Nakamura; T Katagiri

    2007-01-01

    In an attempt to disclose mechanisms of bladder carcinogenesis and discover novel target molecules for development of treatment, we applied a cDNA microarray to screen genes that were significantly transactivated in bladder cancer cells. Among the upregulated genes, we here focused on a novel gene, (DEPDC1) DEP domain containing 1, whose overexpression was confirmed by northern blot and immunohistochemical analyses.

  18. Upregulation of ERG Genes in Candida Species by Azoles and Other Sterol Biosynthesis Inhibitors

    Microsoft Academic Search

    KARL W. HENRY; JOSEPH T. NICKELS; THOMAS D. EDLIND

    2000-01-01

    Infections due to Candida albicans are usually treated with azole antifungals such as fluconazole, but treat- ment failure is not uncommon especially in immunocompromised individuals. Relatedly, in vitro studies dem- onstrate that azoles are nonfungicidal, with continued growth at strain-dependent rates even at high azole con- centrations. We hypothesized that upregulation of ERG11, which encodes the azole target enzyme lanosterol

  19. Mitochondrial Dihydrolipoamide Dehydrogenase is Upregulated in Response to Intermittent Hypoxic Preconditioning.

    PubMed

    Li, Rongrong; Luo, Xiaoting; Wu, Jinzi; Thangthaeng, Nopporn; Jung, Marianna E; Jing, Siqun; Li, Linya; Ellis, Dorette Z; Liu, Li; Ding, Zhengnian; Forster, Michael J; Yan, Liang-Jun

    2015-01-01

    Intermittent hypoxia preconditioning (IHP) has been shown to protect neurons against ischemic stroke injury. Studying how proteins respond to IHP may identify targets that can help fight stroke. The objective of the present study was to investigate whether mitochondrial dihydrolipoamide dehydrogenase (DLDH) would respond to IHP and if so, whether such a response could be linked to neuroprotection in ischemic stroke injury. To do this, we subjected male rats to IHP for 20 days and measured the content and activity of DLDH as well as the three ?-keto acid dehydrogenase complexes that contain DLDH. We also measured mitochondrial electron transport chain enzyme activities. Results show that DLDH content was indeed upregulated by IHP and this upregulation did not alter the activities of the three ?-keto acid dehydrogenase complexes. Results also show that the activities of the five mitochondrial complexes (I-V) were not altered either by IHP. To investigate whether IHP-induced DLDH upregulation is linked to neuroprotection against ischemic stroke injury, we subjected both DLDH deficient mouse and DLDH transgenic mouse to stroke surgery followed by measurement of brain infarction volume. Results indicate that while mouse deficient in DLDH had exacerbated brain injury after stroke, mouse overexpressing human DLDH also showed increased brain injury after stroke. Therefore, the physiological significance of IHP-induced DLDH upregulation remains to be further investigated. PMID:26078703

  20. Alpha lipoic acid induces hepatic fibroblast growth factor 21 expression via up-regulation of CREBH.

    PubMed

    Bae, Kwi-Hyun; Min, Ae-Kyung; Kim, Jung-Guk; Lee, In-Kyu; Park, Keun-Gyu

    2014-12-12

    Hepatic expression of fibroblast growth factor 21 (FGF21), one of the most promising therapeutic candidates for metabolic syndrome, is induced by multiple factors associated with fasting, including cyclic AMP response element-binding protein H (CREBH). Alpha lipoic acid (ALA), a naturally occurring thiol antioxidant, has been shown to induce metabolic changes that are similar to those induced by FGF21, including weight loss and increased energy expenditure. Here, we investigated the effect of ALA on hepatic FGF21 expression. ALA treatment enhanced CREBH and FGF21 mRNA expression and protein abundance in cultured hepatocytes. ALA increased FGF21 promoter activity by up-regulating CREBH expression and increasing CREBH binding to the FGF21 promoter, indicating that ALA up-regulates FGF21 at the transcriptional level. Moreover, inhibition of endogenous CREBH expression by siRNA attenuated ALA-induced FGF21 expression. Finally, treatment of mice with ALA enhanced fasting-induced up-regulation of CREBH and FGF21 in the liver and inhibited feeding-induced suppression of their expression. Consistently, ALA increased serum FGF21 levels in both fasted and fed mice. Collectively, these results indicate that ALA increases hepatic FGF21 expression via up-regulation of CREBH, identifying ALA as a novel positive regulator of FGF21. PMID:25449271

  1. Upregulated PFTK1 promotes tumor cell proliferation, migration, and invasion in breast cancer.

    PubMed

    Gu, Xiaoling; Wang, Yingying; Wang, Hua; Ni, Qichao; Zhang, Chunhui; Zhu, Jia; Huang, Wei; Xu, Pan; Mao, Guoxin; Yang, Shuyun

    2015-07-01

    PFTK1 was a cell division cycle 2-related serine/threonine protein kinase, which was up-regulated in breast cancer tissues and breast cancer lines. And up-regulated PFTK1 was highly associated with grade, axillary lymph node status, and Ki-67. Moreover, Kaplan-Meier curve showed that up-regulated PFTK1 was related to the poor breast carcinoma patients' overall survival. Here, we first discovered and confirmed that cyclin B was a new interacting protein of PFTK1, and the complex might increase the amount of DVL2, which triggers Wnt/?-catenin signaling pathway. Furthermore, knockdown of PFTK1 attenuated cell proliferation, anchorage-independent cell growth, and cell migration and invasion by inhibiting the transcriptional activation of ?-catenin for cyclin D1, MMP9, and HEF1, whereas exogenous expression of PFTK1 might promote MDA-MB-231 cells proliferation, migration, and invasion via promoting PFTK1-DVL2-?-catenin axis. Our findings supported the notion that up-regulated PFTK1 might promote breast cancer progression and metastasis by activating Wnt signaling pathway through the PFTK1-DVL2-?-catenin axis. PMID:26033031

  2. ADAM15 upregulation and interaction with multiple binding partners in inflammatory bowel disease

    Microsoft Academic Search

    Jean-François Mosnier; Anne Jarry; Chantal Bou-Hanna; Marc G Denis; Didier Merlin; Christian L Laboisse

    2006-01-01

    A disintegrin and metalloproteinase (ADAM)15 is upregulated in some tissues undergoing remodeling. This glycoprotein is characterized by adhesive function through its interaction with members of the integrin family and protease properties. The goal of this work was to describe the tissue distribution of ADAM15 and its spatial relationship with its known binding partners in inflammatory bowel disease. ADAM15 expression was

  3. Interplay of Ribosomal DNA Loci in Nucleolar Dominance: Dominant NORs Are Up-Regulated by

    E-print Network

    Shaw, Peter

    , 2008 Copyright: ß 2008 Silva et al. This is an open-access article distributed under the terms` Agricultura, Instituto Superior de Agronomia, Technical University of Lisbon, Tapada da Ajuda, Lisboa in a nucleolar dominance situation. Herein we report dominant NORs up-regulation in the addition line through

  4. DJ-1 upregulates anti-oxidant enzymes and attenuates hypoxia/re-oxygenation-induced oxidative stress by activation of the nuclear factor erythroid 2-like 2 signaling pathway.

    PubMed

    Yan, Yu-Feng; Yang, Wen-Jie; Xu, Qiang; Chen, He-Ping; Huang, Xiao-Shan; Qiu, Ling-Yu; Liao, Zhang-Ping; Huang, Qi-Ren

    2015-09-01

    DJ-1 protein, as a multifunctional intracellular protein, has an important role in transcriptional regulation and anti-oxidant stress. A recent study by our group showed that DJ-1 can regulate the expression of certain anti?oxidant enzymes and attenuate hypoxia/re?oxygenation (H/R)?induced oxidative stress in the cardiomyocyte cell line H9c2; however, the detailed molecular mechanisms have remained to be elucidated. Nuclear factor erythroid 2?like 2 (Nrf2) is an essential transcription factor that regulates the expression of several anti?oxidant genes via binding to the anti?oxidant response element (ARE). The present study investigated whether activation of the Nrf2 pathway is responsible for the induction of anti?oxidative enzymes by DJ?1 and contributes to the protective functions of DJ?1 against H/R?induced oxidative stress in H9c2 cells. The results demonstrated that DJ?1?overexpressing H9c2 cells exhibited anti?oxidant enzymes, including manganese superoxide dismutase, catalase and glutathione peroxidase, to a greater extent and were more resistant to H/R?induced oxidative stress compared with native cells, whereas DJ?1 knockdown suppressed the induction of these enzymes and further augmented the oxidative stress injury. Determination of the importance of Nrf2 in DJ?1?mediated anti?oxidant enzymes induction and cytoprotection against oxidative stress induced by H/R showed that overexpression of DJ?1 promoted the dissociation of Nrf2 from its cytoplasmic inhibitor Keap1, resulting in enhanced levels of nuclear translocation, ARE?binding and transcriptional activity of Nrf2. Of note, Nrf2 knockdown abolished the DJ?1?mediated induction of anti?oxidant enzymes and cytoprotection against oxidative stress induced by H/R. In conclusion, these findings indicated that activation of the Nrf2 pathway is a critical mechanism by which DJ-1 upregulates anti-oxidative enzymes and attenuates H/R-induced oxidative stress in H9c2 cells. PMID:26081287

  5. The effects of different levels of catalase and superoxide dismutase in modified Beltsville extender on rooster post-thawed sperm quality.

    PubMed

    Amini, Mahmood Reza; Kohram, Hamid; Zare-Shahaneh, Ahmad; Zhandi, Mahdi; Sharideh, Hossein; Nabi, Mohammad Mehdi

    2015-06-01

    Oxidative damage of sperm by means of reactive oxygen species generated by the cellular components of semen is one of the main reasons for decreased sperm motility and fertility during the freeze-thawing process. This study was conducted to determine the influence of catalase (CAT) and superoxide dismutase (SOD) on rooster sperm motility, viability and MDA level after freezing and thawing. Semen samples from 10 sexually-mature Ross 308 breeder roosters were collected and pooled, divided into nine equal parts and diluted with modified Beltsville extender containing no antioxidants (control), or supplemented with 50, 100, 200 and 300?g/mL CAT, or 50, 100, 200 and 300U/mL SOD. After thawing, sperm motility and motion parameters were assessed using a CASA system. Sperm viability and MDA level were assessed by eosin-nigrosin and MDA test, respectively. The results of this experiment showed that the extender supplemented with 100 and 200?g CAT, and 50U SOD had the highest sperm motility (P<0.05) in sperm motility. Also, addition 100, 200 and 300?g CAT, and 50U SOD can improve significantly viability after freeze-thaw. Extender supplemented with 100?g CAT had significantly lower MDA level compared to control and 300?g CAT. In conclusion, the results of the present study demonstrate that addition of CAT (100?g/mL) and SOD (50U/mL) independently have beneficial effect on quality of post-thawed rooster semen. PMID:25769553

  6. Catalase-like activity of bovine met-hemoglobin: interaction with the pseudo-catalytic peroxidation of anthracene traces in aqueous medium.

    PubMed

    Paco, Laveille; Galarneau, Anne; Drone, Jullien; Fajula, François; Bailly, Carole; Pulvin, Sylviane; Thomas, Daniel

    2009-10-01

    Hemoglobin is a member of the hemoprotein superfamily whose main role is to transport O(2) in vertebrate organisms. It has two known promiscuous enzymatic activities, peroxidase and oxygenase. Here we show for the first time that bovine hemoglobin also presents a catalase-like activity characterized by a V(max )of 344 microM/min, a K(M )of 24 mM and a k(cat) equal to 115/min. For high anthracene and hemoglobin concentrations and low hydrogen peroxide concentrations, this activity inhibits the expected oxidation of anthracene, which occurs through a peroxidase-like mechanism. Anthracene belongs to the polycyclic aromatic hydrocarbon (PAH) family whose members are carcinogenic and persistent pollutants found in industrial waste waters. Our results show that anthracene oxidation by hemoglobin and hydrogen peroxide follows a typical bi-bi ping-pong mechanism with a V(max) equal to 0.250 microM/min, K(M(H2O2) )of 80 microM, K(M(ANT)) of 1.1 microM and k(cat) of 0.17/min. The oxidation of anthracene is shown to be pseudo-catalytic because an excess of hemoglobin and hydrogen peroxide is required to make PAH completely disappear. Thus, bovine hemoglobin presents, in different degrees, all the catalytic activities of the hemoprotein group, which makes it a very interesting protein for biotechnological processes and one with which structure-activity relationships can be studied. PMID:19606432

  7. Manganese superoxide dismutase (SOD2/MnSOD)/catalase and SOD2/GPx1 ratios as biomarkers for tumor progression and metastasis in prostate, colon, and lung cancer.

    PubMed

    Miar, Ana; Hevia, David; Muñoz-Cimadevilla, Henar; Astudillo, Aurora; Velasco, Julio; Sainz, Rosa M; Mayo, Juan C

    2015-08-01

    The role of manganese-dependent superoxide dismutase (SOD2/MnSOD) during tumor progression has been studied for several decades with controversial results. While SOD2 downregulation was initially associated with tumor initiation and was proposed as a tumor suppressor gene, recent studies have reported that SOD2 might favor tumor progression and dissemination. To our knowledge this is the first time that changes in SOD2 expression in three different types of tumors, i.e., prostate, lung, and colon cancer, are studied by analyzing both SOD2 mRNA and protein levels in a total of 246 patients? samples. In prostate samples, SOD2 protein levels were also increased, especially in middle stage tumors. In the case of colon and lung tumors both mRNA and protein SOD2 levels were increased in malignant tissues compared to those in nontumor samples. More importantly, all metastases analyzed showed increased levels of SOD2 when compared to those of normal primary tissue and healthy adjacent tissue. Together, these results suggest that a common redox imbalance in these three types of tumor occurs at intermediate stages which then might favor migration and invasion, leading to a more aggressive cancer type. Consequently, the ratios SOD2/catalase and SOD2/Gpx1 could be considered as potential markers during progression from tumor growth to metastasis. PMID:25866291

  8. RNAi-Mediated Knockdown of Catalase Causes Cell Cycle Arrest in SL-1 Cells and Results in Low Survival Rate of Spodoptera litura (Fabricius)

    PubMed Central

    Hu, Meiying; Chen, Shaohua; Muhammad, Rizwan-ul-Haq; Dong, Xiaolin; Gong, Liang

    2013-01-01

    Deregulated reactive oxygen species (ROS) production can lead to the disruption of structural and functional integrity of cells as a consequence of reactive interaction between ROS and various biological components. Catalase (CAT) is a common enzyme existing in nearly all organisms exposed to oxygen, which decomposes harmful hydrogen peroxide, into water and oxygen. In this study, the full length sequence that encodes CAT-like protein from Spodoptera litura named siltCAT (GenBank accession number: JQ_663444) was cloned and characterized. Amino acid sequence alignment showed siltCAT shared relatively high conservation with other insect, especially the conserved residues which defined heme and NADPH orientation. Expression pattern analysis showed that siltCAT mRNA was mainly expressed in the fat body, midgut, cuticle and malpighian tube, and as well as over last instar larvae, pupa and adult stages. RNA interference was used to silence CAT gene in SL-1 cells and the fourth-instar stage of S. litura larvae respectively. Our results provided evidence that CAT knockdown induced ROS generation, cell cycle arrest and apoptosis in SL-1 cells. It also confirmed the decrease in survival rate because of increased ROS production in experimental groups injected with double-stranded RNA of CAT (dsCAT). This study implied that ROS scavenging by CAT is important for S. litura survival. PMID:23555693

  9. Dietary long-chain polyunsaturated fatty acids upregulate expression of FADS3 transcripts.

    PubMed

    Reardon, Holly T; Hsieh, Andrea T; Park, Woo Jung; Kothapalli, Kumar S D; Anthony, Joshua C; Nathanielsz, Peter W; Brenna, J Thomas

    2013-01-01

    The fatty acid desaturase (FADS) gene family at 11q12-13.1 includes FADS1 and FADS2, both known to mediate biosynthesis of omega-3 and omega-6 long-chain polyunsaturated fatty acids (LCPUFA). FADS3 is a putative desaturase due to its sequence similarity with FADS1 and FADS2, but its function is unknown. We have previously described 7 FADS3 alternative transcripts (AT) and 1 FADS2 AT conserved across multiple species. This study examined the effect of dietary LCPUFA levels on liver FADS gene expression in vivo and in vitro, evaluated by qRT-PCR. Fourteen baboon neonates were randomized to three diet groups for their first 12 weeks of life, C: Control, no LCPUFA, L: 0.33% docosahexaenoic acid (DHA)/0.67% arachidonic acid (ARA) (w/w); and L3: 1.00% DHA/0.67% ARA (w/w). Liver FADS1 and both FADS2 transcripts were downregulated by at least 50% in the L3 group compared to controls. In contrast, FADS3 AT were upregulated (L3 > C), with four transcripts significantly upregulated by 40% or more. However, there was no evidence for a shift in liver fatty acids to coincide with increased FADS3 expression. Significant upregulation of FADS3 AT was also observed in human liver-derived HepG2 cells after DHA or ARA treatment. The PPAR? antagonist GW9662 prevented FADS3 upregulation, while downregulation of FADS1 and FADS2 was unaffected. Thus, FADS3 AT were directly upregulated by LCPUFA by a PPAR?-dependent mechanism unrelated to regulation of other desaturases. This opposing pattern and mechanism of regulation suggests a dissimilar function for FADS3 AT compared to other FADS gene products. PMID:22398025

  10. Nicotine-induced Up-regulation and Desensitization of 4 2 Neuronal Nicotinic Receptors Depend on Subunit Ratio*

    E-print Network

    Lasalde Dominicc, Jose A. - Department of Biology, Universidad de Puerto Rico

    Nicotine-induced Up-regulation and Desensitization of 4 2 Neuronal Nicotinic Receptors Depend Caribe, Department of Physiology, Bayamo´n, Puerto Rico 00916 Desensitization induced by chronic nicotine exposure has been hypothesized to trigger the up-regulation of the 4 2 neuronal nicotinic acetylcholine

  11. Upregulation of early growth response factor-1 by bile acids requires mitogen-activated protein kinase signaling

    SciTech Connect

    Allen, Katryn [Department of Pharmacology, Toxicology, and Experimental Therapeutics, University of Kansas Medical Center, 4063 KLSIC, 3901 Rainbow Boulevard, Kansas City, KS 66160 (United States); Kim, Nam Deuk; Moon, Jeon-OK [Department of Pharmacology, Toxicology, and Experimental Therapeutics, University of Kansas Medical Center, 4063 KLSIC, 3901 Rainbow Boulevard, Kansas City, KS 66160 (United States); Department of Pharmacy, Pusan National University, Busan 609-735 (Korea, Republic of); Copple, Bryan L., E-mail: bcopple@kumc.ed [Department of Pharmacology, Toxicology, and Experimental Therapeutics, University of Kansas Medical Center, 4063 KLSIC, 3901 Rainbow Boulevard, Kansas City, KS 66160 (United States)

    2010-02-15

    Cholestasis results when excretion of bile acids from the liver is interrupted. Liver injury occurs during cholestasis, and recent studies showed that inflammation is required for injury. Our previous studies demonstrated that early growth response factor-1 (Egr-1) is required for development of inflammation in liver during cholestasis, and that bile acids upregulate Egr-1 in hepatocytes. What remains unclear is the mechanism by which bile acids upregulate Egr-1. Bile acids modulate gene expression in hepatocytes by activating the farnesoid X receptor (FXR) and through activation of mitogen-activated protein kinase (MAPK) signaling. Accordingly, the hypothesis was tested that bile acids upregulate Egr-1 in hepatocytes by FXR and/or MAPK-dependent mechanisms. Deoxycholic acid (DCA) and chenodeoxycholic acid (CDCA) stimulated upregulation of Egr-1 to the same extent in hepatocytes isolated from wild-type mice and FXR knockout mice. Similarly, upregulation of Egr-1 in the livers of bile duct-ligated (BDL) wild-type and FXR knockout mice was not different. Upregulation of Egr-1 in hepatocytes by DCA and CDCA was prevented by the MEK inhibitors U0126 and SL-327. Furthermore, pretreatment of mice with U0126 prevented upregulation of Egr-1 in the liver after BDL. Results from these studies demonstrate that activation of MAPK signaling is required for upregulation of Egr-1 by bile acids in hepatocytes and for upregulation of Egr-1 in the liver during cholestasis. These studies suggest that inhibition of MAPK signaling may be a novel therapy to prevent upregulation of Egr-1 in liver during cholestasis.

  12. Upregulation of early growth response factor-1 by bile acids requires mitogen-activated protein kinase signaling.

    PubMed

    Allen, Katryn; Kim, Nam Deuk; Moon, Jeon-Ok; Copple, Bryan L

    2010-02-15

    Cholestasis results when excretion of bile acids from the liver is interrupted. Liver injury occurs during cholestasis, and recent studies showed that inflammation is required for injury. Our previous studies demonstrated that early growth response factor-1 (Egr-1) is required for development of inflammation in liver during cholestasis, and that bile acids upregulate Egr-1 in hepatocytes. What remains unclear is the mechanism by which bile acids upregulate Egr-1. Bile acids modulate gene expression in hepatocytes by activating the farnesoid X receptor (FXR) and through activation of mitogen-activated protein kinase (MAPK) signaling. Accordingly, the hypothesis was tested that bile acids upregulate Egr-1 in hepatocytes by FXR and/or MAPK-dependent mechanisms. Deoxycholic acid (DCA) and chenodeoxycholic acid (CDCA) stimulated upregulation of Egr-1 to the same extent in hepatocytes isolated from wild-type mice and FXR knockout mice. Similarly, upregulation of Egr-1 in the livers of bile duct-ligated (BDL) wild-type and FXR knockout mice was not different. Upregulation of Egr-1 in hepatocytes by DCA and CDCA was prevented by the MEK inhibitors U0126 and SL-327. Furthermore, pretreatment of mice with U0126 prevented upregulation of Egr-1 in the liver after BDL. Results from these studies demonstrate that activation of MAPK signaling is required for upregulation of Egr-1 by bile acids in hepatocytes and for upregulation of Egr-1 in the liver during cholestasis. These studies suggest that inhibition of MAPK signaling may be a novel therapy to prevent upregulation of Egr-1 in liver during cholestasis. PMID:19931294

  13. Resistance to hydrogen peroxide in Helicobacter pylori: role of catalase (KatA) and Fur, and functional analysis of a novel gene product designated 'KatA-associated protein', KapA (HP0874)

    Microsoft Academic Search

    Andrew G. Harris; Francis E. Hinds; Anthony G. Beckhouse; Tassia Kolesnikow; Stuart L. Hazell

    Helicobacter pylori infection elicits an aggressive inflammatory response that the bacterium is able to resist by virtue of its well-adapted antioxidant defence mechanisms. Catalase (KatA) appears to be a key enzyme in this resistance. Upstream of katA, a low-affinity ferric uptake regulator (Fur)-box has been identified. Downstream of katA, an ORF (HP0874) with no known function has also been identified.

  14. 15d-Prostaglandin J2 activates peroxisome proliferator-activated receptor-?, promotes expression of catalase, and reduces inflammation, behavioral dysfunction, and neuronal loss after intracerebral hemorrhage in rats

    Microsoft Academic Search

    Xiurong Zhao; Yujian Zhang; Roger Strong; James C Grotta; Jaroslaw Aronowski

    2006-01-01

    Peroxisome proliferator-activated receptor-? (PPAR?) is a transcription factor that regulates the expression of various gene products that are essential in lipid and glucose metabolism, as well as that of the peroxisome-enriched antioxidant enzyme, catalase. Activation of PPAR? is linked to anti-inflammatory activities and is beneficial for cardiovascular diseases. However, little is known about its role in intracerebral hemorrhage (ICH). 15-Deoxy-?12,14-prostaglandin

  15. Brain catalase in the streptozotocin-rat model of sporadic Alzheimer's disease treated with the iron chelator-monoamine oxidase inhibitor, M30.

    PubMed

    Sofic, E; Salkovic-Petrisic, M; Tahirovic, I; Sapcanin, A; Mandel, S; Youdim, M; Riederer, P

    2015-04-01

    Low intracerebroventricular (icv) doses of streptozotocin (STZ) produce regionally specific brain neurochemical changes in rats that are similar to those found in the brain of patients with sporadic Alzheimer's disease (sAD). Since oxidative stress is thought to be one of the major pathologic processes in sAD, catalase (CAT) activity was estimated in the regional brain tissue of animals treated intracerebroventricularly with STZ and the multitarget iron chelator, antioxidant and MAO-inhibitor M30 [5-(N-methyl-N-propargylaminomethyl)-8-hydroxyquinoline]. Five-day oral pre-treatment of adult male Wistar rats with 10 mg/kg/day M30 dose was followed by a single injection of STZ (1 mg/kg, icv). CAT activity was measured colorimetrically in the hippocampus (HPC), brain stem (BS) and cerebellum (CB) of the control, STZ-, M30- and STZ + M30-treated rats, respectively, 4 weeks after the STZ treatment. STZ-treated rats demonstrated significantly lower CAT activity in all three brain regions in comparison to the controls (p < 0.05 for BS and CB, p < 0.01 for HPC). M30 pre-treatment of the control rats did not influence the CAT activity in HPC and CB, but significantly increased it in BS (p < 0.05). M30 pre-treatment of STZ-treated rats significantly increased CAT activity in the HPC in comparison to the STZ treatment alone (p < 0.05) and normalized to the control values. These findings are in line with the assumption that reactive oxygen species contribute to the pathogenesis of STZ in a rat model of sAD and indicate that multifunctional iron chelators such as M30 might also have beneficial effects in this non-transgenic sAD model. PMID:25252744

  16. Amplified amperometric aptasensor for selective detection of protein using catalase-functional DNA-PtNPs dendrimer as a synergetic signal amplification label.

    PubMed

    Zhang, Juan; Yuan, Yali; biXie, Shun; Chai, Yaqin; Yuan, Ruo

    2014-10-15

    In this work, we present a new strategy to construct an electrochemical aptasensor for sensitive detection of platelet-derived growth factor BB (PDGF-BB) based on the synergetic amplification of a three-dimensional (3D) nanoscale catalase (CAT) enzyme-functional DNA-platinum nanoparticles (PtNPs) dendrimer through autonomous layer-by-layer assembly. Firstly, polyamidoaminedendrimer (PAMAM) with a hyper-branched and three-dimensional structure was served as nanocarriers to coimmobilize a large number of PDGF-BB binding aptamer (PBA II) and ssDNA 1 (S1) to form PBA II-PAMAM-S1 bioconjugate. In the presence of PDGF-BB, the bioconjugate was self-assembled on the electrode by sandwich assay. Following that, the carried S1 propagated a chain reaction of hybridization events between CAT-PtNPs-S1 and CAT-PtNPs-ssDNA 2 (S2) to form a 3D nanoscale CAT-functional PtNPs-DNA dendrimer, which successfully immobilized substantial CAT enzyme and PtNPs with superior catalysis activity. In this process, the formed negatively charged double-helix DNA could cause the intercalation of hexaammineruthenium(III) chloride (RuHex) into the groove via electrostatic interactions. Thus, numerous RuHex redox probes and CAT were decorated inside/outside of the dendrimer. In the presence of H2O2 in electrolytic cell, the synergistic reaction of CAT and PtNPs towards electrocatalysis could further amplify electrochemical signal. Under optimal condition, the CAT-PtNPs-DNA dendrimer-based sensing system presented a linear dependence between the reduction peak currents and logarithm of PDGF-BB concentrations in the range of 0.00005-35 nM with a relatively low detection limit of 0.02 pM. PMID:24813911

  17. Enhanced Reactive Oxygen Species Scavenging by Overproduction of Superoxide Dismutase and Catalase Delays Postharvest Physiological Deterioration of Cassava Storage Roots1[C][W][OA

    PubMed Central

    Xu, Jia; Duan, Xiaoguang; Yang, Jun; Beeching, John R.; Zhang, Peng

    2013-01-01

    Postharvest physiological deterioration (PPD) of cassava (Manihot esculenta) storage roots is the result of a rapid oxidative burst, which leads to discoloration of the vascular tissues due to the oxidation of phenolic compounds. In this study, coexpression of the reactive oxygen species (ROS)-scavenging enzymes copper/zinc superoxide dismutase (MeCu/ZnSOD) and catalase (MeCAT1) in transgenic cassava was used to explore the intrinsic relationship between ROS scavenging and PPD occurrence. Transgenic cassava plants integrated with the expression cassette p54::MeCu/ZnSOD-35S::MeCAT1 were confirmed by Southern-blot analysis. The expression of MeCu/ZnSOD and MeCAT1 was verified by quantitative reverse transcription-polymerase chain reaction and enzymatic activity analysis both in the leaves and storage roots. Under exposure to the ROS-generating reagent methyl viologen or to hydrogen peroxide (H2O2), the transgenic plants showed higher enzymatic activities of SOD and CAT than the wild-type plants. Levels of malondialdehyde, chlorophyll degradation, lipid peroxidation, and H2O2 accumulation were dramatically reduced in the transgenic lines compared with the wild type. After harvest, the storage roots of transgenic cassava lines show a delay in their PPD response of at least 10 d, accompanied by less mitochondrial oxidation and H2O2 accumulation, compared with those of the wild type. We hypothesize that this is due to the combined ectopic expression of Cu/ZnSOD and CAT leading to an improved synergistic ROS-scavenging capacity of the roots. Our study not only sheds light on the mechanism of the PPD process but also develops an effective approach for delaying the occurrence of PPD in cassava. PMID:23344905

  18. Biogenesis of peroxisomes: immunocytochemical investigation of peroxisomal membrane proteins in proliferating rat liver peroxisomes and in catalase-negative membrane loops

    PubMed Central

    1989-01-01

    Treatment of rats with a new hypocholesterolemic drug BM 15766 induces proliferation of peroxisomes in pericentral regions of the liver lobule with distinct alterations of the peroxisomal membrane (Baumgart, E., K. Stegmeier, F. H. Schmidt, and H. D. Fahimi. 1987. Lab. Invest. 56:554- 564). We have used ultrastructural cytochemistry in conjunction with immunoblotting and immunoelectron microscopy to investigate the effects of this drug on peroxisomal membranes. Highly purified peroxisomal fractions were obtained by Metrizamide gradient centrifugation from control and treated rats. Immunoblots prepared from such peroxisomal fractions incubated with antibodies to 22-, 26-, and 70-kD peroxisomal membrane proteins revealed that the treatment with BM 15766 induced only the 70-kD protein. In sections of normal liver embedded in Lowicryl K4M, all three membrane proteins of peroxisomes could be localized by the postembedding technique. The strongest labeling was obtained with the 22-kD antibody followed by the 70-kD and 26-kD antibodies. In treated animals, double-membraned loops with negative catalase reaction in their lumen, resembling smooth endoplasmic reticulum segments as well as myelin-like figures, were noted in the proximity of some peroxisomes. Serial sectioning revealed that the loops seen at some distance from peroxisomes in the cytoplasm were always continuous with the peroxisomal membranes. The double-membraned loops were consistently negative for glucose-6-phosphatase, a marker for endoplasmic reticulum, but were distinctly labeled with antibodies to peroxisomal membrane proteins. Our observations indicate that these membranous structures are part of the peroxisomal membrane system. They could provide a membrane reservoir for the proliferation of peroxisomes and the expansion of this intracellular compartment. PMID:2544605

  19. Changes in Expression of Manganese Superoxide Dismutase, Copper and Zinc Superoxide Dismutase and Catalase in Brachionus calyciflorus during the Aging Process

    PubMed Central

    Yang, Jianghua; Dong, Siming; Jiang, Qichen; Kuang, Tengjiao; Huang, Wenting; Yang, Jiaxin

    2013-01-01

    Rotifers are useful model organisms for aging research, owing to their small body size (0.1–1 mm), short lifespan (6–14 days) and the relative easy in which aging and senescence phenotypes can be measured. Recent studies have shown that antioxidants can extend the lifespan of rotifers. In this paper, we analyzed changes in the mRNA expression level of genes encoding the antioxidants manganese superoxide dismutase (MnSOD), copper and zinc SOD (CuZnSOD) and catalase (CAT) during rotifer aging to clarify the function of these enzymes in this process. We also investigated the effects of common life-prolonging methods [dietary restriction (DR) and resveratrol] on the mRNA expression level of these genes. The results showed that the mRNA expression level of MnSOD decreased with aging, whereas that of CuZnSOD increased. The mRNA expression of CAT did not change significantly. This suggests that the ability to eliminate reactive oxygen species (ROS) in the mitochondria reduces with aging, thus aggravating the damaging effect of ROS on the mitochondria. DR significantly increased the mRNA expression level of MnSOD, CuZnSOD and CAT, which might explain why DR is able to extend rotifer lifespan. Although resveratrol also increased the mRNA expression level of MnSOD, it had significant inhibitory effects on the mRNA expression of CuZnSOD and CAT. In short, mRNA expression levels of CAT, MnSOD and CuZnSOD are likely to reflect the ability of mitochondria to eliminate ROS and delay the aging process. PMID:23451185

  20. Pepino mosaic virus triple gene block protein 1 (TGBp1) interacts with and increases tomato catalase 1 activity to enhance virus accumulation.

    PubMed

    Mathioudakis, Matthaios M; Veiga, Rita S L; Canto, Tomas; Medina, Vicente; Mossialos, Dimitris; Makris, Antonios M; Livieratos, Ioannis

    2013-08-01

    Various plant factors are co-opted by virus elements (RNA, proteins) and have been shown to act in pathways affecting virus accumulation and plant defence. Here, an interaction between Pepino mosaic virus (PepMV) triple gene block protein 1 (TGBp1; p26) and tomato catalase 1 (CAT1), a crucial enzyme in the decomposition of toxic hydrogen peroxide (H?O?), was identified using the yeast two-hybrid assay, and confirmed via an in?vitro pull-down assay and bimolecular fluorescent complementation (BiFC) in?planta. Each protein was independently localized within loci in the cytoplasm and nuclei, sites at which their interaction had been visualized by BiFC. Following PepMV inoculation, CAT mRNA and protein levels in leaves were unaltered at 0, 3 and 6 days (locally) and 8 days (systemically) post-inoculation; however, leaf extracts from the last two time points contained increased CAT activity and lower H?O? evels. Overexpression of PepMV p26 in?vitro and in?planta conferred the same effect, suggesting an additional involvement of TGBp1 in potexvirus pathogenesis. The accumulation of PepMV genomic and subgenomic RNAs and the expression of viral coat protein in noninoculated (systemic) leaves were reduced significantly in CAT-silenced plants. It is postulated that, during PepMV infection, a p26-CAT1 interaction increases H?O? cavenging, thus acting as a negative regulator of plant defence mechanisms to promote PepMV infections. PMID:23634807

  1. Host genetic variations in glutathione-S-transferases, superoxide dismutases and catalase genes influence susceptibility to malaria infection in an Indian population.

    PubMed

    Fernandes, Rayzel C; Hasan, Marriyah; Gupta, Himanshu; Geetha, K; Rai, Padmalatha S; Hande, Manjunath H; D'Souza, Sydney C; Adhikari, Prabha; Brand, Angela; Satyamoorthy, Kapaettu

    2015-06-01

    Antioxidant enzymes can contribute to disease susceptibility or determine response to therapy in individuals with malaria. Genetic variations due to polymorphisms in host genes encoding antioxidant enzymes such as glutathione S-transferases-theta, mu, pi (GSTT, GSTM, GSTP), superoxide dismutases (SOD) and catalase (CAT), may therefore, influence inter-individual response to malaria pathology and propensity of infection caused by Plasmodium vivax (Pv) and Plasmodium falciparum (Pf). Therefore, using polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) and DNA sequencing, we investigated the association of deletions of GSTT1 and GSTM1, single nucleotide polymorphisms (SNPs) of GSTP1 (rs1695), SOD1 (rs2234694), SOD2 (rs4880, rs1141718), SOD3 (rs2536512) and CAT (rs1001179) in individuals infected with Pf (n = 100) and Pv (n = 100) against healthy controls (n = 150). Our data suggest a significant role for GSTM1 deletions in complicated Pv (p = 0.0007) malaria with ODDs ratio 3.8 [with 95 % confidence interval (CI) 1.9-7.4]. The results also indicated that polymorphisms present in GSTP1, SOD1 and CAT genes may be associated with malaria susceptibility (p < 0.05), whereas SOD3 polymorphism may play a role in malarial resistance (p < 0.05). In addition, we observed significant SNP-SNP interactions with synergistic genetic effects in SOD2, SOD3 and CAT genes for Pv and in SOD2 and SOD3 genes for Pf. In conclusion, our results provide convincing evidence for a relationship between polymorphisms in host antioxidant enzymes and susceptibility to malaria infection. PMID:25573779

  2. Upregulation of c-Myc may contribute to the pathogenesis of canine pemphigus vulgaris.

    PubMed

    Williamson, Lina; Suter, Maja M; Olivry, Thierry; Wyder, Marianne; Müller, Eliane J

    2007-02-01

    The pathomechanism in human pemphigus vulgaris (PV) has recently been described to rely on generalized c-Myc upregulation in skin and oral mucosa followed by hyperproliferation. Here we assessed whether dogs suffering from PV present the same pathological changes as described for human patients with PV. Using immunofluorescence analysis on patients' biopsy samples, we observed marked nuclear c-Myc accumulation in all layers of the epidermis and oral mucosa in all (3/3) dogs analysed. In addition, c-Myc upregulation was accompanied by an increased number of proliferating Ki67-positive cells. These molecular changes were further paralleled by deregulated expression of wound healing and terminal differentiation markers as observed in human PV. Together these findings suggest a common pathomechanism for both species which is of particular relevance in the light of the recently discussed novel therapeutic strategies aiming at targeting PV antibody-induced signalling cascades. PMID:17222234

  3. Up-regulation of cyclooxygenase-2 by product-prostaglandin E2

    NASA Technical Reports Server (NTRS)

    Tjandrawinata, R. R.; Hughes-Fulford, M.

    1997-01-01

    The development of prostate cancer has been linked to high level of dietary fat intake. Our laboratory investigates the connection between cancer cell growth and fatty acid products. Studying human prostatic carcinoma PC-3 cells, we found that prostaglandin E2 (PGE2) increased cell growth and up-regulated the gene expression of its own synthesizing enzyme, cyclooxygenase-2 (COX-2). PGE2 increased COX-2 mRNA expression dose-dependently with the highest levels of stimulation seen at the 3-hour period following PGE2 addition. The NSAID flurbiprofen (5 microM), in the presence of exogenous PGE2, inhibited the up-regulation of COX-2 mRNA and cell growth. These data suggest that the levels of local intracellular PGE2 play a major role in the growth of prostate cancer cells through an activation of COX-2 gene expression.

  4. Up-regulation of the Ire1-mediated signaling molecule, Bip, in ischemic rat brain.

    PubMed

    Ito, D; Tanaka, K; Suzuki, S; Dembo, T; Kosakai, A; Fukuuchi, Y

    2001-12-21

    The endoplasmic reticulum (ER) is thought to play important roles in various neurological diseases via multifactorial and complex mechanisms. The Ire1-mediated signal is part of one ER signaling pathways; the signal induces the expression of an ER-resident protein, Bip/GRP78, and is thought to be involved in cell death under ER stress. In this study, we examined time-dependent Bip expression after transient middle cerebral artery occlusion and characterized the Bip-positive cells. Ire1- mediated molecules, Bip, were rapidly up-regulated in the ischemic area after 3.5 h recirculation. Their immunoreactivity continued to increase until 24-48 h. Immunofluorescence staining revealed Bip up-regulation in ischemic neurons, which were TUNEL positive. Our studies suggest that the Ire1-mediated signal might be associated with ischemic neuronal damage. PMID:11742232

  5. Interferon Lambda Upregulates IDO1 Expression in Respiratory Epithelial Cells After Influenza Virus Infection.

    PubMed

    Fox, Julie M; Crabtree, Jackelyn M; Sage, Leo K; Tompkins, S Mark; Tripp, Ralph A

    2015-07-01

    Influenza infection causes an increase in indoleamine 2, 3-dioxygenase (IDO) activity in the lung parenchyma. IDO catabolizes tryptophan into kynurenine, leading to immune dampening. Multiple cell types express IDO, and while IFN-? upregulates IDO in dendritic cells and macrophages, it is unclear how IDO is affected in respiratory epithelial cells during influenza infection. In this study, the role of IFN-? in IDO regulation was investigated after influenza infection of respiratory epithelial cells. IDO1 expression increased concurrently with IFN-? expression. In differentiated NHBE cells, the IDO metabolite was released basolaterally. Recombinant IFN-? upregulated IDO1 activity, and silencing of IFN-? decreased IDO1 expression during influenza infection. During IFN-? stimulation, most differentiated cell types are able to express IDO but during influenza infection, IDO is primarily expressed in uninfected cells. These studies show a role for IDO in the host response to influenza infection, and they provide insights into novel approaches for enhancing vaccine responses and therapeutic approaches. PMID:25756191

  6. Chronic L-deprenyl-induced up-regulation of the dopamine uptake carrier.

    PubMed

    Wiener, H L; Hashim, A; Lajtha, A; Sershen, H

    1989-04-12

    L-Deprenyl is an inhibitor of monoamine oxidase B and dopamine uptake. Chronic L-deprenyl (10 mg/kg i.p., twice weekly for 4 weeks) was shown to inhibit monoamine oxidase B activity by 89%, and also to induce an up-regulation of the [3H]mazindol binding site associated with the striatal dopamine uptake carrier. Scatchard analysis indicated a 56% increase in the maximal number of [3H]mazindol binding sites in chronic L-deprenyl animals, but no effect on the affinity of these binding sites. The ability of L-deprenyl to up-regulate the [3H]mazindol-associated dopamine uptake carrier appears to be a result of its role as a dopamine uptake inhibitor. PMID:2501102

  7. Dexamethasone transiently attenuates up-regulation of endostatin/collagen XVIII following traumatic brain injury.

    PubMed

    Zhang, Z-Y; Zhang, Z; Fauser, U; Artelt, M; Burnet, M; Schluesener, H J

    2007-07-13

    Endostatin/collagen XVIII is a specific inhibitor of endothelial proliferation and migration in vitro. It has also been shown to have anti-angiogenic activity and tumor growth inhibitory activity in vivo and in vitro. Here we studied expression of endostatin/collagen XVIII in a rat traumatic brain injury (TBI) model, focusing on the early phase. A significant up-regulation of endostatin/collagen XVIII in TBI began as early as 24 h post-TBI. Double-staining experiment revealed that the major resource of endostatin/collagen XVIII(+) cells in our TBI rat model was a subpopulation of reactivated microglia/macrophages. Our data further showed that dexamethasone attenuated up-regulation of endostatin/collagen XVIII expression at days 1 and 2, but not at day 4, post-TBI, indicating that dexamethasone might possess an early and transient influence to the angiogenesis following TBI. PMID:17560042

  8. Atorvastatin Improves Inflammatory Response in Atherosclerosis by Upregulating the Expression of GARP

    PubMed Central

    Zhao, Xiaoqi; Liu, Yuzhou; Zhong, Yucheng; Liu, Bo; Yu, Kunwu; Shi, Huairui; Zhu, Ruirui; Meng, Kai; Zhang, Wei; Wu, Bangwei

    2015-01-01

    Regulatory T cells play an important role in the progression of atherosclerosis. GARP is a newly biological membrane molecule existed on activated Tregs, which is related to the release of TGF-?. The antiatherosclerosis effects of statins partly depend on their multiple immune modulatory potencies. In this paper, we present that atorvastatin could upregulate the expression of GARP and TGF-? in CD4+ T cells and increase the numbers of CD4+LAP+ and CD4+Foxp3+ regulatory T cells in ApoE?/? mice. Also, we indicate that atorvastatin promotes the aggregation of GARP+ and Foxp3+ cells and secretory of the TGF-?1 in atherosclerotic plaques. Furthermore, we prove that atorvastatin could delay the procession of atherosclerosis and improve the stability of atherosclerotic plaques. Interestingly, we report that inhibition of GARP distinctly inhibits the anti-inflammatory effects of atorvastatin. We conclude that atorvastatin improves the inflammatory response in atherosclerosis partly by upregulating the expression of GARP on regulatory T cells.

  9. CD40 and tumour necrosis factor-? co-operate to up-regulate inducuble nitric oxide synthase expression in macrophages

    PubMed Central

    Portillo, Jose-Andres C; Feliciano, Luis Muniz; Okenka, Genevieve; Heinzel, Frederick; Subauste, M Cecilia; Subauste, Carlos S

    2012-01-01

    Regulation of inducible nitric oxide synthase (NOS2) expression is important given the role of this enzyme in inflammation, control of infections and immune regulation. In contrast to tumour necrosis factor-? (TNF-?) alone or CD40 stimulation alone, simultaneous stimulation of mouse macrophages through CD40 ligation and TNF-? led to up-regulation of NOS2 and nitric oxide production. This response was of functional relevance because CD40/TNF-?-stimulated macrophages acquired nitric oxide-dependent anti-Leishmania major activity. CD40 plus TNF-? up-regulated NOS2 independently of interferon-?, interferon-?/? and interleukin-1. TNF receptor-associated factor 6 (TRAF6), an adapter protein downstream of CD40, appears to be required for NOS2 up-regulation because a CD40-TRAF6 blocking peptide inhibited up-regulation of NOS2 in CD40/TNF-?-stimulated macrophages. CCAAT/enhancer-binding protein-? (C/EBP?), a transcription factor activated by TNF-? but not CD40, was required for NOS2 up-regulation because this enzyme was not up-regulated when C/EBP??/? macrophages received CD40 plus TNF-? stimulation. These results indicate that CD40 and TNF-? co-operate to up-regulate NOS2, probably via the effect of TRAF6 and C/EBP?. PMID:22044243

  10. Dengue virus infection induces upregulation of GRP78, which acts to chaperone viral antigen production.

    PubMed

    Wati, S; Soo, M-L; Zilm, P; Li, P; Paton, A W; Burrell, C J; Beard, M; Carr, J M

    2009-12-01

    Dengue virus (DENV) pathogenesis is related to the host responses to viral infection within target cells, and therefore, this study assessed intracellular changes in host proteins following DENV infection. Two-dimensional gel electrophoresis and mass spectrometry identified upregulation of the host endoplasmic reticulum (ER) chaperone GRP78 in K562 cells following DENV infection, in the absence of virus-induced cell death. Upregulation of GRP78 in DENV-infected cells was confirmed by immunostaining and confocal microscopy and by Western blot analysis and was also observed in DENV-infected primary monocyte-derived macrophages, a natural target cell type for DENV infection. GRP78 was upregulated in both DENV antigen-positive and -negative cells in the DENV-infected culture, suggesting a bystander effect, with the highest GRP78 levels coincident with high-level DENV antigen production and infectious-virus release. Transfection of target cells to express GRP78 prior to DENV challenge did not affect subsequent DENV infection, but cleavage of GRP78 with the SubAB toxin, during an established DENV infection, yielded a 10- to 100-fold decrease in infectious-virus release, loss of intracellular DENV particles, and a dramatic decrease in intracellular DENV antigen. However, DENV RNA levels were unchanged, indicating normal DENV RNA replication but altered DENV antigen levels in the absence of GRP78. Thus, GRP78 is upregulated by DENV infection and is necessary for DENV antigen production and/or accumulation. This may be a common requirement for viruses such as flaviviruses that depend heavily on the ER for coordinated protein production and processing. PMID:19793816

  11. Sulpiride, but not haloperidol, up-regulates ?-hydroxybutyrate receptors in vivo and in cultured cells

    Microsoft Academic Search

    Charline Ratomponirina; Serge Gobaille; Yann Hodé; Véronique Kemmel; Michel Maitre

    1998-01-01

    Five days of ?-hydroxybutyrate (GHB) administration (3×500 mg kg?1 day?1 i.p.) to rats resulted in a significant decrease in the density of GHB receptors measured in the whole rat brain without modification of their corresponding affinity. Similar administration of (?)-sulpiride (2×100 mg kg?1 day?1 i.p. for 5 days) induces an up-regulation of GHB receptors without change in their dissociation constants

  12. O-Linked N-Acetylglucosamine Is Upregulated in Alzheimer Brains

    Microsoft Academic Search

    L. S. Griffith; B. Schmitz

    1995-01-01

    We present evidence that the expression of the novel intracellular carbohydrate modification of proteins O-glycosidically linked N-acetylglucosamine (O-GlcNAc) - is significantly upregulated in Alzheimer brains over that of age matched control brains. This increase is specific for proteins associated with the detergent insoluble cytoskeleton and not for proteins of the detergent soluble fraction and is not due to an increase

  13. Clusterin is up-regulated in glomerular mesangial cells in complement-mediated injury

    Microsoft Academic Search

    Koei Yamada; Yuichi Hori; Norio Hanafusa; Toshihiro Okuda; Nobuo Nagano; Nam-Ho Choi-Miura; William G Couser; Toshio Miyata; Kiyoshi Kurokawa; Toshiro Fujita; Masaomi Nangaku

    2001-01-01

    Clusterin is up-regulated in glomerular mesangial cells in complement-mediated injury.BackgroundClusterin is a soluble complement regulatory protein that binds to C5b-7 and inhibits generation of membrane attack complex, C5b-9. Glomerular deposition of clusterin has been observed in human and experimental membranous nephropathy in association with C5b-9 and immune deposits. However, it is controversial as to whether clusterin observed in glomeruli is

  14. Protease nexin 1 in the murine kidney: Glomerular localization and up-regulation in glomerulopathies

    Microsoft Academic Search

    Solange Moll; Nicole Schaeren-Wiemers; Annelise Wohlwend; Yves Pastore; Thierry Fulpius; Denis Monard; André-Pascal Sappino; Jürg A Schifferli; Jean-Dominique Vassalli; Shozo Izui

    1996-01-01

    Protease nexin 1 in the murine kidney: Glomerular localization and up-regulation in glomerulopathies. Protease nexin 1 (PN-1), a potent serpin-class antiprotease, is thought to be synthesized in the murine kidney. However, neither the cellular localization of PN-1 synthesis nor its role has as yet been defined. To address these questions, we determined by in situ hybridizations RNase protection assay and

  15. Tumor-infiltrating regulatory T cells delineated by upregulation of PD-1 and inhibitory receptors.

    PubMed

    Park, Hyo Jin; Kusnadi, Anthony; Lee, Eun-Jung; Kim, Won Woo; Cho, Byoung Chul; Lee, Ik Jae; Seong, Jinsil; Ha, Sang-Jun

    2012-01-01

    Foxp3(+) regulatory T (T(reg)) cells are dominant suppressor cells which regulate conventional T (T(conv)) cells. Inside tumor microenvironment, T(reg) cells have been known to become potent in suppressing T(conv) cell responses, thereby enabling tumor cells to circumvent immune response. However, the underlying mechanism by which tumor-infiltrating T(reg) cells display enhanced suppressive function is still unresolved. To understand characteristics and function of tumor-infiltrating T(reg) cells as well as T(conv) cells in the tumor site, we analyzed their phenotypes either within tumor burden or at distant site of tumor using both heterotopic and orthotopic mouse cancer models. Compared to CD8(+) T cells at distant site of tumor, tumor-infiltrating CD8(+) T cells dramatically upregulated programmed death 1 (PD-1) and other inhibitory receptors, thereby being more exhausted functionally. Tumor-infiltrating CD4(+) T cells also expressed higher level of PD-1 than CD4(+) T cells at distant site of tumor but very surprisingly, upregulation of PD-1 occurred in CD4(+)Foxp3(+) T(reg) as well as CD4(+)Foxp3(-) T(conv) cells. Moreover, tumor infiltrating T(reg) cells upregulated other inhibitory receptors such as T cell immunoglobulin mucin 3 (TIM-3), cytotoxic T lymphocyte antigen-4 (CTLA-4), glucocorticoid-induced tumor necrosis factor receptor (GITR), and lymphocyte activation gene-3 (LAG-3). These results suggest that upregulation of PD-1 and other inhibitory receptors on tumor-infiltrating T(reg) cells is related with their enhanced suppressive function. PMID:23121978

  16. Upregulation of persistent and ramp sodium current in dorsal horn neurons after spinal cord injury

    Microsoft Academic Search

    Angelika Lampert; Bryan C. Hains; Stephen G. Waxman

    2006-01-01

    Traumatic spinal cord injury (SCI) results not only in motor impairment, but also in chronic central neuropathic pain, which often is refractory to conventional treatment approaches. Upregulated expression of sodium channel Nav1.3 has been observed within the spinal dorsal horn neurons after SCI, and appears to contribute to neuronal hyperresponsiveness and pain-related behaviors. In this study we characterized the changes

  17. Upregulation of Endothelial Nitric Oxide Synthase by HMG CoA Reductase Inhibitors

    Microsoft Academic Search

    Ulrich Laufs; Vito La Fata; Jorge Plutzky; James K. Liao

    Background—Oxidized low-density lipoprotein (ox-LDL) causes endothelial dysfunction in part by decreasing the availability of endothelial nitric oxide (NO). Although HMG CoA reductase inhibitors restore endothelial function by reducing serum cholesterol levels, it is not known whether they can also directly upregulate endothelial NO synthase (ecNOS) activity. Methods and Results—Human saphenous vein endothelial cells were treated with ox-LDL (50 mg\\/mL thiobarbituric

  18. Rapid systemic up-regulation of genes after heat-wounding and electrical stimulation

    NASA Technical Reports Server (NTRS)

    Davies, E.; Vian, A.; Vian, C.; Stankovic, B.

    1997-01-01

    When one leaf of a tomato plant is electrically-stimulated or heat-wounded, proteinase inhibitor genes are rapidly up-regulated in distant leaves. The identity of the systemic wound signal(s) is not yet known, but major candidates include hormones transmitted via the phloem or the xylem, the electrically-stimulated self-propagating electrical signal in the phloem (the action potential, AP), or the heat-wound-induced surge in hydraulic pressure in the xylem evoking a local change in membrane potential in adjacent living cells (the variation potential, VP). In order to discriminate between these signals we have adopted two approaches. The first approach involves applying stimuli that evoke known signals and determining whether these signals have similar effects on the "model" transcripts for proteinase inhibitors (pin) and calmodulin (cal). Here we show that a heat wound almost invariably evokes a VP, while an electrical stimulation occasionally evokes an AP, and both of these signals induce accumulation of transcripts encoding proteinase inhibitors. The second approach involves identifying the array of genes turned on by heat-wounding. To this end, we have constructed a subtractive library for heat-wounded tissue, isolated over 800 putatively up-regulated clones, and shown that all but two of the fifty that we have analyzed by Northern hybridization are, indeed, up-regulated. Here we show the early kinetics of up-regulation of three of these transcripts in the terminal (4th) leaf in response to heat-wounding the 3rd leaf, about 5 cm away. Even though these transcripts show somewhat different time courses of induction, with one peaking at 30 min, another at 15 min, and another at 5 min after flaming of a distant leaf, they all exhibit a similar pattern, i.e., a transient period of transcript accumulation preceding a period of transcript decrease, followed by a second period of transcript accumulation.

  19. Phosphorus and uremic serum up-regulate osteopontin expression in vascular smooth muscle cells

    Microsoft Academic Search

    Neal X Chen; Kalisha D O'Neill; Danxia Duan; Sharon M Moe

    2002-01-01

    Phosphorus and uremic serum up-regulate osteopontin expression in vascular smooth muscle cells.BackgroundDialysis patients have accelerated atherosclerosis, with extensive calcification of both the intima and media. Cross-sectional studies have implicated hyperphosphatemia in this process, but the mechanism is unclear.MethodsTo test the hypothesis that hyperphosphatemia and\\/or uremia induces vascular calcification, bovine vascular smooth muscle cells (BVSMC) were treated with increasing concentrations of

  20. Hormonal regulation of cell junction permeability: Upregulation by catecholamine and prostaglandin E 1

    Microsoft Academic Search

    A. Radu; G. Dahl; W. R. Loewenstein

    1982-01-01

    Summary By cellular activation with hormones, we test the proposition (Loewenstein, W.R.,Physiol. Rev.61:829, 1981) that the permeability of cell junction is upregulated through elevation of the level of cyclic AMP. Cultured rat glioma C-6 cells, with ß-adrenergic receptors, and human lung WI-38 cells, with prostaglandin receptors, were exposed to catecholamine (isoproterenol) and prostaglandin E1, respectively, while their junctions were probed

  1. Gene up-regulation in response to predator kairomones in the water flea, Daphnia pulex

    PubMed Central

    2010-01-01

    Background Numerous cases of predator-induced polyphenisms, in which alternate phenotypes are produced in response to extrinsic stimuli, have been reported in aquatic taxa to date. The genus Daphnia (Branchiopoda, Cladocera) provides a model experimental system for the study of the developmental mechanisms and evolutionary processes associated with predator-induced polyphenisms. In D. pulex, juveniles form neckteeth in response to predatory kairomones released by Chaoborus larvae (Insecta, Diptera). Results Previous studies suggest that the timing of the sensitivity to kairomones in D. pulex can generally be divided into the embryonic and postembryonic developmental periods. We therefore examined which of the genes in the embryonic and first-instar juvenile stages exhibit different expression levels in the presence or absence of predator kairomones. Employing a candidate gene approach and identifying differentially-expressed genes revealed that the morphogenetic factors, Hox3, extradenticle and escargot, were up-regulated by kairomones in the postembryonic stage and may potentially be responsible for defense morph formation. In addition, the juvenile hormone pathway genes, JHAMT and Met, and the insulin signaling pathway genes, InR and IRS-1, were up-regulated in the first-instar stage. It is well known that these hormonal pathways are involved in physiological regulation following morphogenesis in many insect species. During the embryonic stage when morphotypes were determined, one of the novel genes identified by differential display was up-regulated, suggesting that this gene may be related to morphotype determination. Biological functions of the up-regulated genes are discussed in the context of defense morph formation. Conclusions It is suggested that, following the reception of kairomone signals, the identified genes are involved in a series of defensive phenotypic alterations and the production of a defensive phenotype. PMID:20433737

  2. Upregulation of articular synovial membrane ?-opioid-like receptors in an acute equine synovitis model.

    PubMed

    van Loon, J P A M; de Grauw, J C; Brunott, A; Weerts, E A W S; van Weeren, P R

    2013-04-01

    Intra-articular injection of opioids provides analgesia in painful equine joints and ?-opioid receptors (MORs) have been demonstrated in equine synovial membranes. The aim of this study was to determine whether acute inflammatory conditions will lead to up-regulation of MOR in equine synovial membranes and whether anti-inflammatory treatment can prevent any such upregulation. In a two-period, blinded, placebo-controlled randomised cross-over design, lipopolysaccharide (LPS, 1.0 ng) was injected into the left or right middle carpal joint of seven healthy ponies. Arthroscopy and synovial membrane biopsy was performed under general anaesthesia at baseline, 48 h (T48) and 672 h (T672) after LPS injection, with ponies assigned to receive either phenylbutazone (PBZ 2.2mg/kg PO BID) or placebo from 2h post-LPS. Ponies were scored for pain and lameness. Repeated synovial fluid samples were obtained and the degree of synovitis scored both macroscopically and microscopically. The density and staining pattern of MOR-like protein in synovial membrane biopsies over the course of the synovitis with or without PBZ treatment was evaluated using immunohistochemical techniques. LPS injection consistently induced a severe transient synovitis. Pain and lameness were significantly attenuated by treatment with PBZ. Up-regulation of MOR-like protein in the inflamed equine synovial membrane could be demonstrated in the placebo treated animals, but not in the PBZ-treated animals overall, although there were no significant differences at any individual time-point between the two groups. It was concluded that acute inflammation will up-regulate MOR, while anti-inflammatory treatment will attenuate this response. PMID:22939088

  3. The glutathione peroxidase homologous gene from Chlamydomonas reinhardtii is transcriptionally up-regulated by singlet oxygen

    Microsoft Academic Search

    Urs Leisinger; Karin Rüfenacht; Beat Fischer; Manuel Pesaro; Arik Spengler; Alexander J. B. Zehnder; Rik I. L. Eggen

    2001-01-01

    The glutathione peroxidase homologous gene (Gpxh gene) in Chlamydomonas reinhardtii is up-regulated under oxidative stress conditions. The Gpxh gene showed a remarkably strong and fast induction by the singlet oxygen-generating photosensitizers neutral red, methylene blue and rose Bengal. The Gpxh mRNA levels strongly increased, albeit much more slowly, upon exposure to the organic hydroperoxides tert-butyl hydroperoxide (t-BOOH) and cumene hydroperoxide.

  4. Airway epithelial platelet-activating factor receptor expression is markedly upregulated in chronic obstructive pulmonary disease

    PubMed Central

    Shukla, Shakti Dhar; Sohal, Sukhwinder Singh; Mahmood, Malik Quasir; Reid, David; Muller, Hans Konrad; Walters, Eugene Haydn

    2014-01-01

    Background We recently published that platelet-activating factor receptor (PAFr) is upregulated on the epithelium of the proximal airways of current smokers and also in bronchial epithelial cells exposed to cigarette smoke extract. These treated cells also showed upregulation of Streptococcus pneumoniae adhesion. Bacterial wall phosphorylcholine specifically binds to PAFr expressed on airway epithelium, thus facilitating adherence and tissue invasion, which may be relevant to chronic obstructive pulmonary disease (COPD). Moreover, the use of inhaled corticosteroids (ICS) in COPD patients is associated with an increased risk of invasive respiratory pneumococcal infections. Objective In this study, we have investigated whether PAFr expression is especially upregulated in airway epithelium in COPD patients and whether this expression may be modulated by ICS therapy. Methods We cross-sectionally evaluated PAFr expression in bronchial biopsies from 15 COPD patients who were current smokers (COPD-smokers) and 12 COPD-ex-smokers, and we compared these to biopsies from 16 smokers with normal lung function. We assessed immunostaining with anti-PAFr monoclonal antibody. We also used material from a previous double-blinded randomized placebo-controlled 6-month ICS intervention study in COPD patients to explore the effect of ICS on PAFr expression. We employed computer-aided image analysis to quantify the percentage of epithelium stained for PAFr. Results Markedly enhanced expression of PAFr was found in both COPD-smokers (P<0.005) and COPD-ex-smokers (P<0.002) compared to smokers with normal lung function. There was little evidence that PAFr expression was affected by ICS therapy over 6 months. Conclusion Epithelial PAFr expression is upregulated in smokers, especially in those with COPD, and is not obviously affected by ICS therapy. PMID:25143722

  5. Upregulation of Na-coupled Glucose transporter SGLT1 by Tau Tubulin Kinase 2

    Microsoft Academic Search

    Ioana Alesutan; Mentor Sopjani; Miribane Dërmaku-Sopjani; Carlos Munoz; Jakob Voelkl; Florian Lang

    2012-01-01

    The Tau-tubulin-kinase 2 (TTBK2) is a serine\\/threonine kinase expressed in various tissues including tumors. Up-regulation of TTBK2 increases resistance of tumor cells against antiangiogenic treatment and confers cell survival. Tumor cell survival critically depends on cellular uptake of glucose, which is partially accomplished by SGLT1 (SLC5A1) mediated Na+-coupled glucose transport. The present study explored whether TTBK2 participates in the regulation

  6. Selective CB2 up-regulation in women affected by endometrial inflammation.

    PubMed

    Iuvone, Teresa; De Filippis, Daniele; Di Spiezio Sardo, Attilio; D'Amico, Alessandra; Simonetti, Sara; Sparice, Stefania; Esposito, Giuseppe; Bifulco, Giuseppe; Insabato, Luigi; Nappi, Carmine; Guida, Maurizio

    2008-04-01

    Endometritis is defined as an inflammation of the endometrial mucosa of the uterus. In endometritis large amounts of toxic mediators, including nitric oxide (NO) are released by inflammatory cells. As a consequence of nitric oxide-dependent injury, the cells respond by triggering protective mechanisms, by changing the endocannabinoid system (ECS) which comprises both CB(1) and CB(2) cannabinoid receptors and their endogenous ligands. The aim of our study was to seek out evidence for the presence of cannabinoid receptors in inflammatory endometrial tissue as well as for their potential role in endometrial inflammation. Our results showed a selective up-regulation of both transcription and expression of CB(2) receptors in biopsies from women affected by endometrial inflammation compared to healthy women. The experiments with the nitric oxide-donor S-Nitroso-L-Glutathione (GSNO) suggest that such a selective up-regulation may be related to the nitric oxide release occurring during endometrial inflammation. In addition, we demonstrated an increase in chymase expression, a marker of mast cells, in biopsies of women affected by endometritis. Therefore our results support the hypothesis that the up-regulation of CB(2) occurs mainly on mast cells and that it might tend to sensitize these cells to the anti-inflammatory effect exerted by endogenous cannabinoids by binding their receptor and thus preventing the mast cell degranulation and the release of pro-inflammatory mediators. In conclusion, we believe that the selective CB(2) up-regulation might play a role as a novel prognostic factor in endometrial inflammation. PMID:18419603

  7. Liver cell proliferation requires methionine adenosyltransferase 2A mRNA up-regulation

    Microsoft Academic Search

    Covadonga Pañeda; Itziar Gorospe; Blanca Herrera; Toshikazu Nakamura; Isabel Fabregat; Isabel Varela-Nieto

    2002-01-01

    Regulation of liver cell proliferation is a key event to control organ size during development and liver regeneration. Methionine adenosyltransferase (MAT) 2A is expressed in proliferating liver, whereas MAT1A is the form expressed in adult quiescent hepatocytes. Here we show that, in H35 hepatoma cells, growth factors such as hepatocyte growth factor (HGF) and insulin up-regulated MAT2A expression. HGF actions

  8. Interferon ?-Inducible Protein 27 (IFI27) is Upregulated in Psoriatic Skin and Certain Epithelial Cancers

    Microsoft Academic Search

    Sari Suomela; Li Cao; Anne Bowcock; Ulpu Saarialho-Kere

    2004-01-01

    IFI27 is an interferon ?-inducible protein found to be upregulated in lesional and non-lesional psoriatic skin in a gene array study. To further characterize its function, we studied by in situ hybridization whether IFI27 is expressed in psoriasis, other inflammatory skin diseases, and wound repair in vivo. We also examined its regulation by different growth factors and anti-psoriatic agents using

  9. Dexamethasone transiently attenuates up-regulation of endostatin\\/collagen XVIII following traumatic brain injury

    Microsoft Academic Search

    Z.-Y. Zhang; Z. Zhang; U. Fauser; M. Artelt; M. Burnet; H. J. Schluesener

    2007-01-01

    Endostatin\\/collagen XVIII is a specific inhibitor of endothelial proliferation and migration in vitro. It has also been shown to have anti-angiogenic activity and tumor growth inhibitory activity in vivo and in vitro. Here we studied expression of endostatin\\/collagen XVIII in a rat traumatic brain injury (TBI) model, focusing on the early phase. A significant up-regulation of endostatin\\/collagen XVIII in TBI

  10. Upregulation of cytosolic NADP + -dependent isocitrate dehydrogenase by hyperglycemia protects renal cells against oxidative stress

    Microsoft Academic Search

    Soh-Hyun Lee; Sun-Ok Ha; Ho-Jin Koh; KilSoo Kim; Seon-Min Jeon; Myung-Sook Choi; Oh-Shin Kwon; Tae-Lin Huh

    2010-01-01

    Hyperglycemia-induced oxidative stress is widely recognized as a key mediator in the pathogenesis of diabetic nephropathy,\\u000a a complication of diabetes. We found that both expression and enzymatic activity of cytosolic NADP+-dependent isocitrate dehydrogenase (IDPc) were upregulated in the renal cortexes of diabetic rats and mice. Similarly, IDPc\\u000a was induced in murine renal proximal tubular OK cells by high hyperglycemia, while

  11. Bile acids mimic oxidative stress induced upregulation of thioredoxin reductase in colon cancer cell lines.

    PubMed

    Lechner, Sandra; Müller-Ladner, Ulf; Schlottmann, Klaus; Jung, Barbara; McClelland, Michael; Rüschoff, Josef; Welsh, John; Schölmerich, Jürgen; Kullmann, Frank

    2002-08-01

    Bile acids have been suggested to play an important role in the etiology of colon and gastric cancer after gastrectomy, but the molecular biology of these effects is poorly understood. We evaluated the effect of different bile acids on human gastric and colon carcinoma cells and identified genes by RNA arbitrarily primed PCR for differential display that are modulated following treatment with hydrophobic bile acids. Thioredoxin reductase (TR) mRNA was upregulated after treatment with taurochenodeoxycholic acid (TCDCA) in St 23132 cells. This raised the question whether deoxycholic acid (DCA) would have regulative effects on TR in HT-29 cells. After an incubation time of 6 h with DCA, TR mRNA expression was increased up to threefold. Ursodeoxycholic acid had no influence on TR mRNA expression. The upregulation of TR after DCA incubation was almost identical to incubation with 12-O-tetradecanoylphorbol-13-acetate. This implies that hydrophobic bile acids mediate oxidative stress in gastrointestinal cancer cells, which was confirmed by measurement of oxidative burst after treatment with DCA. The results suggest that hydrophobic bile acids induce oxidative stress in gastrointestinal cancer resulting in a compensatory upregulation of TR mRNA, one of the key components in the complex anti-oxidant defense system within eukaryotic cells. The activation of at least parts of the redox signaling system is potentially related to the cytotoxicity and the stimulation of the cell death machinery induced by toxic bile acids. PMID:12151345

  12. Stromal fibroblasts in the microenvironment of gastric carcinomas promote tumor metastasis via upregulating TAGLN expression

    PubMed Central

    2013-01-01

    Background Fibroblasts play a critical role in tumorigenesis, tumor progression and metastasis. However, their detailed molecular characteristics and clinical significance are still elusive. TAGLN is an actin-binding protein that plays an important role in tumorigenesis. Results We investigated the interaction between cancer cells and the tumor microenvironment to determine how the fibroblasts from human gastric carcinoma facilitate tumorigenesis through TAGLN. QRT-PCR and Western blot indicated that TAGLN expression was upregulated in gastric carcinoma-associated fibroblasts (CAFs) that promote gastric cancer cell migration and invasion. Using small interfering RNA (siRNA), we found that CAFs enhanced tumor metastasis through upregulated TAGLN in vitro and in vivo. The expression of matrix metalloproteinase-2 (MMP-2) was significantly lower after TAGLN knock-down by siRNA. TAGLN levels were elevated in human gastric cancer stroma than normal gastric stroma and associated with differentiation and lymph node metastasis of gastric cancer. Conclusion CAFs may promote gastric cancer cell migration and invasion via upregulating TAGLN and TAGLN induced MMP-2 production. PMID:23510049

  13. Upregulation of galectin-3 in immortalized Schwann cells IFRS1 under diabetic conditions.

    PubMed

    Tsukamoto, Masami; Sango, Kazunori; Niimi, Naoko; Yanagisawa, Hiroko; Watabe, Kazuhiko; Utsunomiya, Kazunori

    2015-03-01

    A spontaneously immortalized adult Fischer rat Schwann cell line IFRS1 retains the characteristic features of normal Schwann cells, and can be a useful tool for the study of diabetic neuropathy. In the present study, we examined the effects of high glucose and 3-deoxyglucosone (3-DG) on the viability and the protein expression of advanced glycation endproducts (AGE)-binding proteins, such as galectin-3 (GAL-3) and receptor for AGE (RAGE) in IFRS1 cells. Exposure to 30mM of glucose or 0.2mM of 3-DG for 7 days failed to impair the IFRS1 cell viability, but significantly upregulated the expression of GAL-3. The same exposure tended to increase the expression of RAGE, but the changes were not significant. The high glucose-induced upregulation of GAL-3 was attenuated by cotreatment with 0.2mM of an anti-glycated agent aminoguanidine or 20nM of an anti-oxidant trans-resveratrol. In addition, treatment of IFRS1 cells with 1?g/ml of recombinant GAL-3 for 48h resulted in the upregulation of B-cell lymphoma 2 (Bcl-2) and the downregulation of 4-hydroxynonenal (4HNE). These findings suggest the involvement of GAL-3 in the glycation and oxidative stress under diabetic conditions and its cytoprotective role in Schwann cells. PMID:25481849

  14. Up-regulation of interleukin 4/B-cell stimulatory factor 1 receptor expression

    SciTech Connect

    Ohara, J.; Paul, W.E. (National Institutes of Health, Bethesda, MD (USA))

    1988-11-01

    The expression of interleukin 4 (IL-4) receptors on resting T and B lymphocytes was enhanced 4- to 8-fold by IL-4 stimulation of these cells. Other agents such as lipopolysaccharide and anti-IgM for B cells and concanvalain A for T cells also caused increased IL-4 receptor expression, although to a somewhat smaller degree than IL-4. Using a newly developed flow cytometric analysis based on the binding of biotinylated IL-4 and phycoerythrin-streptavidin, it was observed that receptor up-regulation in a T-cell population treated with IL-4 was a feature of the majority of the T cells. Analysis of IL-4 by cross-linkage of {sup 125}I-labeled IL-4 to IL-4 receptor with disuccinimidyl suberate indicated that the IL-4 IL-4 receptor complex was the same size in the resting and up-regulated cells, implying that the same receptor species found in resting cells was up-regulated in response IL-4.

  15. Identification of up-regulated genes in amphioxus neurula and the expression of AmphiFABP.

    PubMed

    Liu, Xiaohui; Sun, Yi; Zhang, Juyong; Li, Guang; Wang, Yiquan

    2011-01-01

    Amphioxus is a good model organism for understanding the origin and developmental mechanism of vertebrates owing to its important evolutionary position. During the developmental process of amphioxus embryo, the neurula is a crucial stage because of neural tube and notochord formation as well as somite emergence at this stage. In order to isolate genes up-regulated at the neurula stage, we constructed an 11-hour neurula subtracted cDNA library of amphioxus Branchiostoma belcheri and sequenced 204 ESTs representing 82 contigs. Comparative analysis revealed that 55% of those contigs were homologous to various known genes while 45% of them had no significant similarity to any known genes. Those observations imply that the un-identified ESTs might contain some new genes which are involved in the development of amphioxus neurula. Real-time quantitative PCR (RTqPCR) indicated that the expression levels of 14 genes are up-regulated after gastrulation among 20 assayed genes. Of those up-regulated genes, we further cloned and sequenced the full-length of fatty acid binding protein gene (AmphiFABP). The deduced protein sequence was similar to that of vertebrate brain FABP and heart FABP, and in situ hybridization displayed that AmphiFABP, similar to their vertebrate cognates, was expressed not only in nervous system but also in embryonic somite and gut, hinting a multifunctional property of AmphiFABP in amphioxus. PMID:21498921

  16. Selective Up-regulation of Human Selenoproteins in Response to Oxidative Stress*

    PubMed Central

    Touat-Hamici, Zahia; Legrain, Yona; Bulteau, Anne-Laure; Chavatte, Laurent

    2014-01-01

    Selenocysteine is inserted into selenoproteins via the translational recoding of a UGA codon, normally used as a stop signal. This process depends on the nature of the selenocysteine insertion sequence element located in the 3? UTR of selenoprotein mRNAs, selenium bioavailability, and, possibly, exogenous stimuli. To further understand the function and regulation of selenoproteins in antioxidant defense and redox homeostasis, we investigated how oxidative stress influences selenoprotein expression as a function of different selenium concentrations. We found that selenium supplementation of the culture media, which resulted in a hierarchical up-regulation of selenoproteins, protected HEK293 cells from reactive oxygen species formation. Furthermore, in response to oxidative stress, we identified a selective up-regulation of several selenoproteins involved in antioxidant defense (Gpx1, Gpx4, TR1, SelS, SelK, and Sps2). Interestingly, the response was more efficient when selenium was limiting. Although a modest change in mRNA levels was noted, we identified a novel translational control mechanism stimulated by oxidative stress that is characterized by up-regulation of UGA-selenocysteine recoding efficiency and relocalization of SBP2, selenocysteine-specific elongation factor, and L30 recoding factors from the cytoplasm to the nucleus. PMID:24706762

  17. Neuropilin-2 is upregulated in lung cancer cells during TGF?1-induced epithelial-mesenchymal transition

    PubMed Central

    Nasarre, Patrick; Gemmill, Robert M.; Potiron, Vincent A.; Roche, Joëlle; Lu, Xian; Barón, Anna E.; Korch, Christopher; Garrett-Mayer, Elizabeth; Lagana, Alessandro; Howe, Philip H.; Drabkin, Harry A.

    2014-01-01

    The epithelial-mesenchymal transition (EMT) and its reversal, MET, are fundamental processes involved in tumor cell invasion and metastasis. SEMA3F is a secreted semaphorin and tumor suppressor downregulated by TGF?1 and ZEB1-induced EMT. Here we report that NRP2, the high-affinity receptor for SEMA3F and a co-receptor for certain growth factors, is upregulated during TGF?1-driven EMT in lung cancer cells. Mechanistically, NRP2 upregulation was T?RI-dependent and SMAD-independent, occurring mainly at a post-transcriptional level involving increased association of mRNA with polyribosomes. ERK and AKT inhibition blocked NRP2 upregulation, while RNAi-mediated attenuation of ZEB1 reduced steady-state NRP2 levels. Additionally, NRP2 attenuation inhibited TGF?1-driven morphologic transformation, migration/invasion, ERK activation, growth suppression and changes in gene expression. In a mouse xenograft model of lung cancer, NRP2 attenuation also inhibited locally invasive features of the tumor and reversed TGF?1-mediated growth inhibition. In support of these results, in human lung cancer specimens with the highest NRP2 expression were predominantly E-cadherin negative. Furthermore, the presence of NRP2 staining strengthened the association of E-cadherin loss with high-grade tumors. Together, our results demonstrate that NRP2 contributes significantly to TGF?1-induced EMT in lung cancer. PMID:24121493

  18. Neuropilin-2 Is upregulated in lung cancer cells during TGF-?1-induced epithelial-mesenchymal transition.

    PubMed

    Nasarre, Patrick; Gemmill, Robert M; Potiron, Vincent A; Roche, Joëlle; Lu, Xian; Barón, Anna E; Korch, Christopher; Garrett-Mayer, Elizabeth; Lagana, Alessandro; Howe, Philip H; Drabkin, Harry A

    2013-12-01

    The epithelial-mesenchymal transition (EMT) and its reversal, mesenchymal-epithelial transition (MET), are fundamental processes involved in tumor cell invasion and metastasis. SEMA3F is a secreted semaphorin and tumor suppressor downregulated by TGF-?1 and ZEB1-induced EMT. Here, we report that neuropilin (NRP)-2, the high-affinity receptor for SEMA3F and a coreceptor for certain growth factors, is upregulated during TGF-?1-driven EMT in lung cancer cells. Mechanistically, NRP2 upregulation was T?RI dependent and SMAD independent, occurring mainly at a posttranscriptional level involving increased association of mRNA with polyribosomes. Extracellular signal-regulated kinase (ERK) and AKT inhibition blocked NRP2 upregulation, whereas RNA interference-mediated attenuation of ZEB1 reduced steady-state NRP2 levels. In addition, NRP2 attenuation inhibited TGF-?1-driven morphologic transformation, migration/invasion, ERK activation, growth suppression, and changes in gene expression. In a mouse xenograft model of lung cancer, NRP2 attenuation also inhibited locally invasive features of the tumor and reversed TGF-?1-mediated growth inhibition. In support of these results, human lung cancer specimens with the highest NRP2 expression were predominantly E-cadherin negative. Furthermore, the presence of NRP2 staining strengthened the association of E-cadherin loss with high-grade tumors. Together, our results demonstrate that NRP2 contributes significantly to TGF-?1-induced EMT in lung cancer. PMID:24121493

  19. Up-regulation of telomerase activity in human pancreatic cancer cells after exposure to etoposide

    PubMed Central

    Sato, N; Mizumoto, K; Kusumoto, M; Nishio, S; Maehara, N; Urashima, T; Ogawa, T; Tanaka, M

    2000-01-01

    Telomerase plays a critical role in the development of cellular immortality and oncogenesis. Activation of telomerase occurs in a majority of human malignant tumours, and the relation between telomerase and vulnerability to drug-mediated apoptosis remains unclear. In this study, we demonstrate, for the first time, up-regulation of telomerase activity in human pancreatic cancer cells treated with etoposide, a topoisomerase II inhibitor. Exposure of MIA PaCa-2 cells to etoposide at various concentrations (1–30 ?M) resulted in two- to threefold increases in telomerase activity. Up-regulation was detectable 24 h after drug exposure and was accompanied by enhanced expression of mRNA of the human telomerase reverse transcriptase. Telomerase activation was also observed in AsPC-1 and PANC-1 cells but not in KP-3 and KP-1N cells. Furthermore, we found a negative correlation between increased telomerase activity and the percentage of dead cells after etoposide treatment. These findings suggest the existence of an anti-apoptotic pathway through which telomerase is up-regulated in response to DNA damage. This telomerase activation pathway may be one of the mechanisms responsible for the development of etoposide resistance in certain pancreatic cancer cells. © 2000 Cancer Research Campaign PMID:10839297

  20. Upregulation of HYAL1 Expression in Breast Cancer Promoted Tumor Cell Proliferation, Migration, Invasion and Angiogenesis

    PubMed Central

    Tan, Jin-Xiang; Li, Hong-Yuan; Shi, Yuan; Wang, Liang; Ren, Guo-Sheng

    2011-01-01

    Hyaluronic acid (HA) is a component of the Extra-cellular matrix (ECM), it is closely correlated with tumor cell growth, proliferation, metastasis and angiogenesis, etc. Hyaluronidase (HAase) is a HA-degrading endoglycosidase, levels of HAase are elevated in many cancers. Hyaluronidase-1 (HYAL1) is the major tumor-derived HAase. We previously demonstrated that HYAL1 were overexpression in human breast cancer. Breast cancer cells with higher HAase expression, exhibited significantly higher invasion ability through matrigel than those cells with lower HAase expression, and knockdown of HYAL1 expression in breast cancer cells resulted in decreased cell growth, adhesion, invasion and angiogenesis. Here, to further elucidate the function of HYAL1 in breast cancer, we investigated the consequences of forcing HYAL1 expression in breast cancer cells by transfection of expression plasmid. Compared with control, HYAL1 up-regulated cells showed increased the HAase activity, and reduced the expression of HA in vitro. Meantime, upregulation of HYAL1 promoted the cell growth, migration, invasion and angiogenesis in vitro. Moreover, in nude mice model, forcing HYAL1 expression induced breast cancer cell xenograft tumor growth and angiogenesis. Interestingly, the HA expression was upregulated by forcing HYAL1 expression in vivo. These findings suggested that HYAL1-HA system is correlated with the malignant behavior of breast cancer. PMID:21829529

  1. Transcriptome analysis reveals upregulation of bitter taste receptors in severe asthmatics.

    PubMed

    Orsmark-Pietras, Christina; James, Anna; Konradsen, Jon R; Nordlund, Björn; Söderhäll, Cilla; Pulkkinen, Ville; Pedroletti, Christophe; Daham, Kameran; Kupczyk, Maciek; Dahlén, Barbro; Kere, Juha; Dahlén, Sven-Erik; Hedlin, Gunilla; Melén, Erik

    2013-07-01

    The causes of severe childhood asthma are poorly understood. Our aim was to define global patterns of gene expression in children with severe therapy-resistant and controlled asthma. White blood cells were isolated and the global transcriptome profile was characterised using the Affymetrix Human Gene ST 1.0 chip in children with severe, therapy-resistant asthma (n=17), controlled asthma (n=19) and healthy controls (n=18). Receptor expression was studied in separated leukocyte fractions from asthmatic adults (n=12). Overall, 1378 genes were differentially expressed between children with severe/controlled asthma and controls. Three significantly enriched Kyoto Encyclopedia of Genes and Genomes pathways were represented: natural killer cell-mediated cytotoxicity (upregulated in controlled asthma); N-glycan biosynthesis (downregulated in severe asthma); and bitter taste transduction receptors (TAS2Rs) (upregulated in severe asthma). Quantitative PCR experiments confirmed upregulation of TAS2Rs in severe asthmatics. TAS2R expression was replicated in leukocytes from adult asthmatics, in which TAS2R agonists also inhibited LPS-induced cytokine release. Significant correlations between expression of TAS2Rs and clinical markers of asthma severity were found in both adults and children. In conclusion, specific gene expression patterns were observed in children with severe, therapy-resistant asthma. The increased expression of bronchodilatory TAS2Rs suggests a new target for the treatment of asthma. PMID:23222870

  2. 20-hydroxyecdysone upregulates Atg genes to induce autophagy in the Bombyx fat body

    PubMed Central

    Tian, Ling; Ma, Li; Guo, Enen; Deng, Xiaojuan; Ma, Sanyuan; Xia, Qingyou; Cao, Yang; Li, Sheng

    2013-01-01

    Autophagy is finely regulated at multiple levels and plays crucial roles in development and disease. In the fat body of the silkworm, Bombyx mori, autophagy occurs and Atg gene expression peaks during the nonfeeding molting and pupation stages when the steroid hormone (20-hydroxyecdysone; 20E) is high. Injection of 20E into the feeding larvae upregulated Atg genes and reduced TORC1 activity resulting in autophagy induction in the fat body. Conversely, RNAi knockdown of the 20E receptor partner (USP) or targeted overexpression of a dominant negative mutant of the 20E receptor (EcRDN) in the larval fat body reduced autophagy and downregulated the Atg genes, confirming the importance of 20E-induction of Atg gene expression during pupation. Moreover, in vitro treatments of the larval fat body with 20E upregulated the Atg genes. Five Atg genes were potentially 20E primary-responsive, and a 20E response element was identified in the Atg1 (ortholog of human ULK1) promoter region. Furthermore, RNAi knockdown of 4 key genes (namely Br-C, E74, HR3 and ?ftz-F1) in the 20E-triggered transcriptional cascade reduced autophagy and downregulated Atg genes to different levels. Taken together, we conclude that in addition to blocking TORC1 activity for autophagosome initiation, 20E upregulates Atg genes to induce autophagy in the Bombyx fat body. PMID:23674061

  3. Elastin fragments induce IL-1beta upregulation via NF-kappaB pathway in melanoma cells.

    PubMed

    Debret, Romain; Le Naour, Richard R; Sallenave, Jean-Michel; Deshorgue, Aurelie; Hornebeck, William G; Guenounou, Moncef; Bernard, Philippe; Antonicelli, Frank D

    2006-08-01

    In a previous work, we reported the influence of elastin fragments (EFs) on matrix metalloproteinases-2 and -14 expression and activation in melanoma cells in vitro. We hypothesized that EFs might also modulate expression of other mediators involved during melanoma progression. Therefore we investigated the contribution of EFs on IL-1beta expression, a cytokine playing a key role in melanoma cells activation. Our results evidenced that high tumorigenic melanoma cells (M3Da cells) treated with EFs led to IL-1beta mRNA and protein upregulation. The effects of EFs on M3Da cells were found to be mediated by receptor (spliced galactosidase) occupancy, as being suppressed by lactose and reproduced by cell stimulation with the VGVAPG peptide. Binding of EFs to their receptor induced a rapid activation of extracellular signal-regulated kinase 1/2; and p38 mitogen-activated protein kinase pathways. However, these pathways were not associated with IL-1beta mRNA upregulation by EFs. Concomitantly, we demonstrated that EFs stimulation induced NF-kappaB nuclear translocation and DNA binding on IL-1beta promoter region whereas inhibition of NF-kappaB with the specific chemical inhibitor SN-50 or by overexpression of IkappaB, the endogenous inhibitor of NF-kappaB pathway, totally abolished EFs-mediated IL-1beta mRNA overexpression. These results demonstrate that EFs induce NF-kappaB activation, leading to IL-1beta upregulation in invasive melanoma cells. PMID:16675961

  4. Liver cell proliferation requires methionine adenosyltransferase 2A mRNA up-regulation.

    PubMed

    Pañeda, Covadonga; Gorospe, Itziar; Herrera, Blanca; Nakamura, Toshikazu; Fabregat, Isabel; Varela-Nieto, Isabel

    2002-06-01

    Regulation of liver cell proliferation is a key event to control organ size during development and liver regeneration. Methionine adenosyltransferase (MAT) 2A is expressed in proliferating liver, whereas MAT1A is the form expressed in adult quiescent hepatocytes. Here we show that, in H35 hepatoma cells, growth factors such as hepatocyte growth factor (HGF) and insulin up-regulated MAT2A expression. HGF actions were time- and dose-response dependent and required transcriptional activity. Mitogen-activated protein (MAP) kinase and phosphatidylinositol 3-phosphate kinase (PI 3-K) pathways were required for both HGF-induced cell proliferation and MAT2A up-regulation. Furthermore, in H35 cells treated with HGF, the inhibition of these pathways was associated with the switch from the expression of fetal liver MAT2A to the adult liver MAT1A isoform. Fetal liver hepatocytes exhibited an identical response pattern. Treatment of H35 hepatoma cells with MAT2A antisense oligonucleotides decreased cell proliferation induced by HGF; this decrease correlated with the decay in MAT2A messenger RNA (mRNA) levels. Finally, growth inhibitors such as transforming growth factor (TGF) beta blocked HGF-induced MAT2A up-regulation while increasing MAT1A mRNA levels in H35 cells. In conclusion, our results show that MAT2A expression not only correlates with liver cell proliferation but is required for this process. PMID:12029623

  5. Identification of a conserved set of upregulated genes in mouse skeletal muscle hypertrophy and regrowth.

    PubMed

    Chaillou, Thomas; Jackson, Janna R; England, Jonathan H; Kirby, Tyler J; Richards-White, Jena; Esser, Karyn A; Dupont-Versteegden, Esther E; McCarthy, John J

    2015-01-01

    The purpose of this study was to compare the gene expression profile of mouse skeletal muscle undergoing two forms of growth (hypertrophy and regrowth) with the goal of identifying a conserved set of differentially expressed genes. Expression profiling by microarray was performed on the plantaris muscle subjected to 1, 3, 5, 7, 10, and 14 days of hypertrophy or regrowth following 2 wk of hind-limb suspension. We identified 97 differentially expressed genes (?2-fold increase or ?50% decrease compared with control muscle) that were conserved during the two forms of muscle growth. The vast majority (?90%) of the differentially expressed genes was upregulated and occurred at a single time point (64 out of 86 genes), which most often was on the first day of the time course. Microarray analysis from the conserved upregulated genes showed a set of genes related to contractile apparatus and stress response at day 1, including three genes involved in mechanotransduction and four genes encoding heat shock proteins. Our analysis further identified three cell cycle-related genes at day and several genes associated with extracellular matrix (ECM) at both days 3 and 10. In conclusion, we have identified a core set of genes commonly upregulated in two forms of muscle growth that could play a role in the maintenance of sarcomere stability, ECM remodeling, cell proliferation, fast-to-slow fiber type transition, and the regulation of skeletal muscle growth. These findings suggest conserved regulatory mechanisms involved in the adaptation of skeletal muscle to increased mechanical loading. PMID:25554798

  6. Identification of Anaplasma marginale proteins specifically upregulated during colonization of the tick vector.

    PubMed

    Ramabu, Solomon S; Ueti, Massaro W; Brayton, Kelly A; Baszler, Timothy V; Palmer, Guy H

    2010-07-01

    The transition between infection of the mammalian host and colonization of an arthropod vector is required for the ongoing transmission of a broad array of pathogens, from viruses to protozoa. Understanding how this transition is mediated provides opportunities to disrupt transmission through either chemotherapy or immunization. We used an unbiased proteomic screen to identify Anaplasma marginale proteins specifically upregulated in the tick compared to the mammalian host. Comparative mass spectrometric analysis of proteins separated by two-dimensional gel electrophoresis of uninfected and infected ISE6 cells and infected mammalian cells identified 15 proteins exclusively expressed or upregulated in tick cells. All 15 had originally been annotated as hypothetical proteins. We confirmed quantitative upregulation and expression in situ within the midgut epithelial and salivary gland acinar cells of vector ticks during successful transmission. The results support the hypothesis that A. marginale gene expression is regulated by the specific host environment and, in a broader context, that the core genome evolved in the arthropod vector with differential regulation, allowing adaptation to mammalian hosts. Furthermore, the confirmation of the in situ expression of candidates identified in ISE6 cell lines indicates that this approach may be widely applicable to bacteria in the genera Anaplasma and Ehrlichia, removing a major technical impediment to the identification of new targets for vaccine and chemotherapeutic blocking of transmission. PMID:20439479

  7. Identification of Anaplasma marginale Proteins Specifically Upregulated during Colonization of the Tick Vector?

    PubMed Central

    Ramabu, Solomon S.; Ueti, Massaro W.; Brayton, Kelly A.; Baszler, Timothy V.; Palmer, Guy H.

    2010-01-01

    The transition between infection of the mammalian host and colonization of an arthropod vector is required for the ongoing transmission of a broad array of pathogens, from viruses to protozoa. Understanding how this transition is mediated provides opportunities to disrupt transmission through either chemotherapy or immunization. We used an unbiased proteomic screen to identify Anaplasma marginale proteins specifically upregulated in the tick compared to the mammalian host. Comparative mass spectrometric analysis of proteins separated by two-dimensional gel electrophoresis of uninfected and infected ISE6 cells and infected mammalian cells identified 15 proteins exclusively expressed or upregulated in tick cells. All 15 had originally been annotated as hypothetical proteins. We confirmed quantitative upregulation and expression in situ within the midgut epithelial and salivary gland acinar cells of vector ticks during successful transmission. The results support the hypothesis that A. marginale gene expression is regulated by the specific host environment and, in a broader context, that the core genome evolved in the arthropod vector with differential regulation, allowing adaptation to mammalian hosts. Furthermore, the confirmation of the in situ expression of candidates identified in ISE6 cell lines indicates that this approach may be widely applicable to bacteria in the genera Anaplasma and Ehrlichia, removing a major technical impediment to the identification of new targets for vaccine and chemotherapeutic blocking of transmission. PMID:20439479

  8. Lysophosphatidic Acid Upregulates Laminin-332 Expression during A431 Cell Colony Dispersal

    PubMed Central

    Yamashita, Hironobu; Tripathi, Manisha; Jourquin, Jerome; Kam, Yoonseok; Liu, Shanshan; Weidow, Brandy; Quaranta, Vito

    2010-01-01

    Lysophosphatidic acid (LPA) is a bioactive phospholipid that affects various biological functions, such as cell proliferation, migration, survival, wound healing, and tumor invasion through LPA receptors. Previously, we reported that LPA induces A431 colony dispersal, accompanied by disruption of cell-cell contacts and cell migration. However, it remains unclear how LPA affects cell migration and gene expression during A431 colony dispersal. In this paper, we performed cDNA microarray analysis to investigate this question by comparing gene expression between untreated and LPA-treated A431 cells. Interestingly, these results revealed that LPA treatment upregulates several TGF-?1 target genes, including laminin-332 (Ln-332) components (?3, ?3, and ?2 chains). Western blot analysis also showed that LPA increased phosphorylation of Smad2, an event that is carried out by TGF-?1 interactions. Among the genes upregulated, we further addressed the role of Ln-332. Real-time PCR analysis confirmed the transcriptional upregulation of all ?3, ?3, and ?2 chains of Ln-332 by LPA, corresponding to the protein level increases revealed by western blot. Further, the addition of anti-Ln-332 antibody prevented LPA-treated A431 colonies from dispersing. Taken together, our results suggest that LPA-induced Ln-332 plays a significant role in migration of individual cells from A431 colonies. PMID:20862207

  9. Statins Decrease Lung Inflammation in Mice by Upregulating Tetraspanin CD9 in Macrophages

    PubMed Central

    Jin, Yingji; Tachibana, Isao; Takeda, Yoshito; He, Ping; Kang, Sujin; Suzuki, Mayumi; Kuhara, Hanako; Tetsumoto, Satoshi; Tsujino, Kazuyuki; Minami, Toshiyuki; Iwasaki, Takeo; Nakanishi, Kaori; Kohmo, Satoshi; Hirata, Haruhiko; Takahashi, Ryo; Inoue, Koji; Nagatomo, Izumi; Kida, Hiroshi; Kijima, Takashi; Ito, Mari; Saya, Hideyuki; Kumanogoh, Atsushi

    2013-01-01

    Tetraspanins organize protein complexes in tetraspanin-enriched membrane microdomains that are distinct from lipid rafts. Our previous studies suggested that reduction in the levels of tetraspanins CD9 and CD81 may be involved in the progression of inflammatory lung diseases, especially COPD. To search for agents that increase the levels of these tetraspanins, we screened 1,165 drugs in clinical use and found that statins upregulate CD9 and CD81 in RAW264.7 macrophages. The lipophilic statins, fluvastatin and simvastatin, reversed LPS-induced downregulation of CD9 and CD81, simultaneously preventing TNF-? and matrix metalloproteinase-9 production and spreading of RAW264.7 cells. These statins exerted anti-inflammatory effects in vitro in wild-type macrophages but not in CD9 knockout macrophages, and decreased lung inflammation in vivo in wild-type mice but not in CD9 knockout mice, suggesting that their effects are dependent on CD9. Mechanistically, the statins promoted reverse transfer of the LPS-signaling mediator CD14 from lipid rafts into CD9-enriched microdomains, thereby preventing LPS receptor formation. Finally, upregulation of CD9/CD81 by statins was related to blockade of GTPase geranylgeranylation in the mevalonate pathway. Our data underscore the importance of the negative regulator CD9 in lung inflammation, and suggest that statins exert anti-inflammatory effects by upregulating tetraspanin CD9 in macrophages. PMID:24040034

  10. Insecticide-Mediated Up-Regulation of Cytochrome P450 Genes in the Red Flour Beetle (Tribolium castaneum)

    PubMed Central

    Liang, Xiao; Xiao, Da; He, Yanping; Yao, Jianxiu; Zhu, Guonian; Zhu, Kun Yan

    2015-01-01

    Some cytochrome P450 (CYP) genes are known for their rapid up-regulation in response to insecticide exposures in insects. To date, however, limited information is available with respect to the relationships among the insecticide type, insecticide concentration, exposure duration and the up-regulated CYP genes. In this study, we examined the transcriptional response of eight selected CYP genes, including CYP4G7, CYP4Q4, CYP4BR3, CYP12H1, CYP6BK11, CYP9D4, CYP9Z5 and CYP345A1, to each of four insecticides in the red flour beetle, Tribolium castaneum. Reverse transcription quantitative PCR (RT-qPCR) revealed that CYP4G7 and CYP345A1 can be significantly up-regulated by cypermethrin (1.97- and 2.06-fold, respectively), permethrin (2.00- and 2.03-fold) and lambda-cyhalothrin (1.73- and 1.81-fold), whereas CYP4BR3 and CYP345A1 can be significantly up-regulated by imidacloprid (1.99- and 1.83-fold) when 20-day larvae were exposed to each of these insecticides at the concentration of LC20 for 24 h. Our studies also showed that similar levels of up-regulation can be achieved for CYP4G7, CYP4BR3 and CYP345A1 by cypermethrin, permethrin, lambda-cyhalothrin or imidacloprid with approximately one fourth of LC20 in 6 h. Our study demonstrated that up-regulation of these CYP genes was rapid and only required low concentrations of insecticides, and the up-regulation not only depended on the CYP genes but also the type of insecticides. Our results along with those from previous studies also indicated that there were no specific patterns for predicting the up-regulation of specific CYP gene families based on the insecticide classification. PMID:25607733

  11. Insecticide-mediated up-regulation of cytochrome P450 genes in the red flour beetle (Tribolium castaneum).

    PubMed

    Liang, Xiao; Xiao, Da; He, Yanping; Yao, Jianxiu; Zhu, Guonian; Zhu, Kun Yan

    2015-01-01

    Some cytochrome P450 (CYP) genes are known for their rapid up-regulation in response to insecticide exposures in insects. To date, however, limited information is available with respect to the relationships among the insecticide type, insecticide concentration, exposure duration and the up-regulated CYP genes. In this study, we examined the transcriptional response of eight selected CYP genes, including CYP4G7, CYP4Q4, CYP4BR3, CYP12H1, CYP6BK11, CYP9D4, CYP9Z5 and CYP345A1, to each of four insecticides in the red flour beetle, Tribolium castaneum. Reverse transcription quantitative PCR (RT-qPCR) revealed that CYP4G7 and CYP345A1 can be significantly up-regulated by cypermethrin (1.97- and 2.06-fold, respectively), permethrin (2.00- and 2.03-fold) and lambda-cyhalothrin (1.73- and 1.81-fold), whereas CYP4BR3 and CYP345A1 can be significantly up-regulated by imidacloprid (1.99- and 1.83-fold) when 20-day larvae were exposed to each of these insecticides at the concentration of LC20 for 24 h. Our studies also showed that similar levels of up-regulation can be achieved for CYP4G7, CYP4BR3 and CYP345A1 by cypermethrin, permethrin, lambda-cyhalothrin or imidacloprid with approximately one fourth of LC20 in 6 h. Our study demonstrated that up-regulation of these CYP genes was rapid and only required low concentrations of insecticides, and the up-regulation not only depended on the CYP genes but also the type of insecticides. Our results along with those from previous studies also indicated that there were no specific patterns for predicting the up-regulation of specific CYP gene families based on the insecticide classification. PMID:25607733

  12. Involvement of MAPK Activation in Bacterial Endotoxin-Inducible Tissue Factor Upregulation in Human Monocytic THP1 Cells

    Microsoft Academic Search

    Arthur J. Chu; Zhen-Guo Wang; Melissa A. Walton; Ann Seto

    2001-01-01

    Background. Monocytic tissue factor (mTF) hypercoagulation leading to thrombotic complications is commonly observed following sepsis.Objective. We herein study the intracellular mechanism of mTF upregulation in human model monocytic THP-1 cells in response to bacterial endotoxin (lipopolysaccharide, LPS; Escherichia coli O111:B04), determining if mitogen-activated protein kinase (MAPK) activation is involved in the signaling.Methods. We assessed mTF upregulation by its cell surface

  13. Uncoupling protein-2 up-regulation and enhanced cyanide toxicity are mediated by PPAR{alpha} activation and oxidative stress

    SciTech Connect

    Zhang, X.; Li, L.; Prabhakaran, K.; Zhang, L.; Leavesley, H.B.; Borowitz, J.L. [Department of Medicinal Chemistry and Molecular Pharmacology, Purdue University, West Lafayette, IN 47907-1333 (United States); Isom, G.E. [Department of Medicinal Chemistry and Molecular Pharmacology, Purdue University, West Lafayette, IN 47907-1333 (United States)], E-mail: geisom@purdue.edu

    2007-08-15

    Uncoupling protein 2 (UCP-2) is an inner mitochondrial membrane proton carrier that modulates mitochondrial membrane potential ({delta}{psi}{sub m}) and uncouples oxidative phosphorylation. We have shown that up-regulation of UCP-2 by Wy14,643, a selective peroxisome proliferator-activated receptor-{alpha} (PPAR{alpha}) agonist, enhances cyanide cytotoxicity. The pathway by which Wy14,643 up-regulates UCP-2 was determined in a dopaminergic cell line (N27 cells). Since dopaminergic mesencephalic cells are a primary brain target of cyanide, the N27 immortalized mesencephalic cell was used in this study. Wy14,643 produced a concentration- and time-dependent up-regulation of UCP-2 that was linked to enhanced cyanide-induced cell death. MK886 (PPAR{alpha} antagonist) or PPAR{alpha} knock-down by RNA interference (RNAi) inhibited PPAR{alpha} activity as shown by the peroxisome proliferator response element-luciferase reporter assay, but only partially decreased up-regulation of UCP-2. The role of oxidative stress as an alternative pathway to UCP-2 up-regulation was determined. Wy14,643 induced a rapid surge of ROS generation and loading cells with glutathione ethyl ester (GSH-EE) or pre-treatment with vitamin E attenuated up-regulation of UCP-2. On the other hand, RNAi knockdown of PPAR{alpha} did not alter ROS generation, suggesting a PPAR{alpha}-independent component to the response. Co-treatment with PPAR{alpha}-RNAi and GSH-EE blocked both the up-regulation of UCP-2 by Wy14,643 and the cyanide-induced cell death. It was concluded that a PPAR{alpha}-mediated pathway and an oxidative stress pathway independent of PPAR{alpha} mediate the up-regulation of UCP-2 and subsequent increased vulnerability to cyanide-induced cytotoxicity.

  14. Dichloroacetate- and Trichloroacetate-Induced Modulation of Superoxide Dismutase, Catalase, and Glutathione Peroxidase Activities and Glutathione Level in the livers of Mice after Subacute and Subchronic exposure

    PubMed Central

    Hassoun, Ezdihar A.; Cearfoss, Jacquelyn

    2010-01-01

    Dichloroacetate (DCA) and trichloroacetate (TCA) were previously found to induce various levels of oxidative stress in the hepatic tissues of mice after subacute and subchronic exposure. The cells are known to have several protective mechansims against production of oxidative stress by different xenobiotics. To assess the roles of the antioxidant enzymes and glutathione (GSH) in DCA- and TCA-induced oxidative stress, groups of B6C3F1 mice were administered either DCA or TCA at doses of 7.7, 77, 154 and 410 mg/kg/day, by gavage for 4 weeks (4-W) and 13 weeks (13-W), and superoxide dismutase (SOD) catalase (CAT) and glutathione peroxidase (GSH-Px) activities, as well as GSH were determined in the hepatic tissues. DCA at doses ranging between 7.7-410, and 7.7-77 mg/kg/day, given for 4-W and 13-W, respectively, resulted in either suppression or no change in SOD, CAT and GSH-Px activities, but doses of 154-410 mg DCA/kg/day administered for 13-W were found to result in significant induction of the three enzyme activities. TCA administration on the other hand, resulted in increases in SOD and CAT activities, and suppression of GSH-Px activity in both periods. Except for the DCA doses of 77-154 mg/kg/day administered for 13-W that resulted in significant reduction in GSH levels, all other DCA, as well as TCA treatments produced no changes in GSH. Since these enzymes are involved in the detoxification of the reactive oxygen species (ROS), superoxide anion (SA) and H2O2, it is concluded that SA is the main contributor to DCA-induced oxidative stress while both ROS contribute to that of TCA. The increases in the enzyme activities associated with 154-410 mg DCA/kg/day in the 13-W period suggest their role as protective mechanisms contributing to the survival of cells modified in response to those treatments. PMID:21170174

  15. The Natural Antimicrobial Enzyme Lysozyme is Up-Regulated in Gastrointestinal Inflammatory Conditions

    PubMed Central

    Rubio, Carlos A.

    2014-01-01

    The cells that line the mucosa of the human gastrointestinal tract (GI, that is, oral cavity, oesophagus, stomach, small intestine, large intestine, and rectum) are constantly challenged by adverse micro-environmental factors, such as different pH, enzymes, and bacterial flora. With exception of the oral cavity, these microenvironments also contain remnant cocktails of secreted enzymes and bacteria from upper organs along the tract. The density of the GI bacteria varies, from 103/mL near the gastric outlet, to 1010/mL at the ileocecal valve, to 1011 to 1012/mL in the colon. The total microbial population (ca. 1014) exceeds the total number of cells in the tract. It is, therefore, remarkable that despite the prima facie inauspicious mixture of harmful secretions and bacteria, the normal GI mucosa retains a healthy state of cell renewal. To counteract the hostile microenvironment, the GI epithelia react by speeding cell exfoliation (the GI mucosa has a turnover time of two to three days), by increasing peristalsis, by eliminating bacteria through secretion of plasma cell-immunoglobulins and by increasing production of natural antibacterial compounds, such as defensin-5 and lysozyme. Only recently, lysozyme was found up-regulated in Barrett’s oesophagitis, chronic gastritis, gluten-induced atrophic duodenitis (coeliac disease), collagenous colitis, lymphocytic colitis, and Crohn’s colitis. This up-regulation is a response directed to the special types of bacteria recently detected in these diseases. The aim of lysozyme up-regulation is to protect individual mucosal segments to chronic inflammation. The molecular mechanisms connected to the crosstalk between the intraluminal bacterial flora and the production of lysozyme released by the GI mucosae, are discussed. Bacterial resistance continues to exhaust our supply of commercial antibiotics. The potential use of lysozyme to treat infectious diseases is receiving much attention. PMID:25437608

  16. Estradiol improves cardiovascular function through up-regulation of SOD2 on vascular wall

    PubMed Central

    Liu, Zhaoyu; Gou, Yulan; Zhang, Hongyu; Zuo, Houjuan; Zhang, Haimou; Liu, Zhengxiang; Yao, Dachun

    2014-01-01

    Epidemiological studies have shown that estrogens have protective effects in cardiovascular diseases, even though the results from human clinical trials remain controversial, while most of the animal experiments confirmed this effect, but the detailed mechanism remains unclear. In this study, we found that estradiol (E2) treatment significantly increases the expression of mitochondrial superoxide dismutase (SOD2) in mice and in vitro in human aorta endothelial cells. Further investigation shows that E2 up-regulates SOD2 through tethering of estrogen receptor (ER) to Sp1 and the increased binding of Sp1 to GC-box on the SOD2 promoter, where ER? responses E2-mediated gene activation, and ER? maintains basal gene expression level. The E2/ER-mediated SOD2 up-regulation results in minimized ROS generation, which highly favors healthy cardiovascular function. Gene therapy through lentivirus-carried endothelium-specific delivery to the vascular wall in high-fat diet (HFT) mice shows that the SOD2 expression in endothelial cells normalizes E2 deficiency-induced ROS generation with ameliorated mitochondrial dysfunction and vascular damage, while SOD2 knockdown worsens the problem despite the presence of E2, indicating that E2-induced SOD2 expression plays an important vasculoprotective role. To our knowledge, this is the first report for the mechanism by which E2 improves cardiovascular function through up-regulation of SOD2 in endothelial cells. In turn, this suggests a novel gene therapy through lentivirus-carried gene delivery to vascular wall for E2 deficiency-induced cardiovascular damage in postmenopausal women. PMID:25462070

  17. Up-regulation of nicotinic acetylcholine receptors in menthol cigarette smokers

    PubMed Central

    Brody, Arthur L; Mukhin, Alexey G; La Charite, Jaime; Ta, Karen; Farahi, Judah; Sugar, Catherine A.; Mamoun, Michael S.; Vellios, Evan; Archie, Meena; Kozman, Maggie; Phuong, Jonathan; Arlorio, Franca; Mandelkern, Mark A.

    2013-01-01

    One-third of smokers primarily use menthol cigarettes and usage of these cigarettes leads to elevated serum nicotine levels and more difficulty quitting in standard treatment programmes. Previous brain imaging studies demonstrate that smoking (without regard to cigarette type) leads to up-regulation of ?2*-containing nicotinic acetylcholine receptors (nAChRs). We sought to determine if menthol cigarette usage results in greater nAChR up-regulation than non-menthol cigarette usage. Altogether, 114 participants (22 menthol cigarette smokers, 41 non-menthol cigarette smokers and 51 non-smokers) underwent positron emission tomography scanning using the ?4?2* nAChR radioligand 2-[18F]fluoro-A-85380 (2-FA). In comparing menthol to non-menthol cigarette smokers, an overall test of 2-FA total volume of distribution values revealed a significant between-group difference, resulting from menthol smokers having 9–28% higher ?4?2* nAChR densities than non-menthol smokers across regions. In comparing the entire group of smokers to non-smokers, an overall test revealed a significant between-group difference, resulting from smokers having higher ?4?2* nAChR levels in all regions studied (36–42%) other than thalamus (3%). Study results demonstrate that menthol smokers have greater up-regulation of nAChRs than non-menthol smokers. This difference is presumably related to higher nicotine exposure in menthol smokers, although other mechanisms for menthol influencing receptor density are possible. These results provide additional information about the severity of menthol cigarette use and may help explain why these smokers have more trouble quitting in standard treatment programmes. PMID:23171716

  18. IFN-gamma upregulation and protection by macrophage-adapted infectious bursal disease virus.

    PubMed

    Khatri, Mahesh; Sharma, Jagdev M

    2008-08-26

    Infectious bursal disease virus (IBDV) causes an acute, highly contagious and immunosuppressive disease in chickens. The virus infects and destroys actively dividing IgM-bearing B cells in the bursa. Although antibody response is considered important in defense against virulent IBDV, antibody alone is not sufficient and cell-mediated immunity (CMI) appears to play a critical role. We serially passaged classical IBDV (cIBDV) in MQ-NCSU, an avian macrophage cell line. The macrophage-adapted virus (mcIBDV) was used in ovo to immunize chickens. mcIBDV, which was non-pathogenic and highly protective, induced anti-IBDV antibody and, most importantly, upregulated the expression of IFN-gamma mRNA in spleen. The IFN-gamma upregulation by mcIBDV was significantly higher (P<0.05) than that induced by a commercially available vaccine originated from adaptation of cIBDV in the tissue culture (chicken embryo fibroblast (CEF) cells) (tcIBDV). The level of IFN-gamma upregulation by cIBDV that had been adapted by serial passages to CEF (fcIBDV) was similar to that by tcIBDV and significantly lower (P<0.05) than that by mcIBDV. Virus load was significantly higher (P<0.05) in spleen macrophages obtained from mcIBDV-inoculated chickens than that from fcIBDV-inoculated chickens. These data indicated that adaptation of IBDV to macrophages enhanced the ability of the virus to induce cell-mediated immune response in chickens. PMID:18601966

  19. The ?v?6 integrin promotes an osteolytic program through upregulation of MMP2

    PubMed Central

    Dutta, Anindita; Li, Jing; Lu, Huimin; Akech, Jacqueline; Pratap, Jitesh; Wang, Tao; Zerlanko, Brad J.; FitzGerald, Thomas J.; Jiang, Zhong; Birbe, Ruth; Wixted, John; Violette, Shelia M.; Stein, Janet L.; Stein, Gary S.; Lian, Jane B.; Languino, Lucia R.

    2014-01-01

    The molecular circuitries controlling osseous prostate metastasis are known to depend on the activity of multiple pathways, including integrin signaling. Here, we demonstrate that the ?v?6 integrin is upregulated in human prostate cancer bone metastasis. In prostate cancer cells, this integrin is a functionally active receptor for fibronectin and latency associated peptide-TGF?1; it mediates attachment and migration upon ligand binding and is localized in focal contacts. Given the propensity of prostate cancer cells to form bone metastatic lesions, we investigated whether the ?v?6 integrin promotes this type of metastasis. We show for the first time that ?v?6 selectively induces matrix metalloproteinase 2, MMP2, in vitro in multiple prostate cancer cells, and promotes osteolysis in vivo in an immunodeficient mouse model of bone metastasis through upregulation of MMP2, but not MMP9. The effect of ?v?6 on MMP2 expression and activity is independent of androgen receptor in the analyzed prostate cancer cells. Increased levels of PTHrP, known to induce osteoclastogenesis, were also observed in ?v?6 expressing cells. However, using MMP2 shRNA, we demonstrate that the ?v?6 effect on bone loss is due to upregulation of soluble MMP2 by the cancer cells, not to changes in tumor growth rate. Another related ?v-containing integrin, ?v?5, fails to show similar responses, underscoring the significance of ?v?6 activity. Overall, these mechanistic studies establish that expression of a single integrin, ?v?6, contributes to the cancer cell -mediated program of osteolysis by inducing matrix degradation through MMP2. Our results open new prospects for molecular therapy of metastatic bone disease. PMID:24385215

  20. Upregulation of macrophage-specific functions by oxidized LDL: lysosomal degradation-dependent and -independent pathways.

    PubMed

    Radhika, A; Sudhakaran, P R

    2013-01-01

    Formation of foam cells from macrophages, which are formed by the differentiation of blood-borne monocytes, is a critical early event in atherogenesis. To examine how pre-exposure of monocytes to modified proteins, such as oxLDL, influences their differentiation to macrophages, an in vitro model system using isolated PBMC maintained in culture in the presence of oxLDL was used. Pretreatment of monocytes with oxLDL caused a faster rate of expression of macrophage-specific functions and loss of monocyte-specific functions compared to unmodified LDL. The effect of oxidation of lipid component of LDL by CuSO(4) and its protein component by HOCl, on mo-m? differentiation was studied by monitoring the upregulation of macrophage-specific functions, particularly MMP-9. Chloroquine, a lysosomal degradation blocker, significantly reversed the effect mediated by CuSO(4) oxLDL, indicating the involvement of lysosomal degradation products, while no such effect was observed in HOCl oxLDL-treated cells, indicating the existence of a pathway independent of its lysosomal degradation products. Reversal of the effect of oxLDL by NAC and Calphostin C, an inhibitor of PKC, suggested the activation of RO-mediated signaling pathways. Use of inhibitors of signaling pathways showed that CuSO(4) oxLDL upregulated m?-specific MMP-9 through p38 MAPK and Akt-dependent pathways, while HOCl oxLDL utilized ERK ½ and Akt. Further analysis showed the activation of PPAR? and AP-1 in CuSO(4) oxLDL, while HOCl-oxLDL-mediated effect involved NF?B and AP-1. These results suggest that lipid oxLDL- and protein oxLDL-mediated upregulation of mo-m?-specific functions involve lysosomal degradation-dependent and -independent activation of intracellular signaling pathways. PMID:23054190

  1. Importance of ERK1/2 in upregulation of endothelin type B receptors in cerebral arteries

    PubMed Central

    Henriksson, Marie; Xu, Cang-Bao; Edvinsson, Lars

    2004-01-01

    This study examines the importance of mitogen-activated protein kinases (MAPKs) in upregulation of endothelin type B (ETB) receptors. Rat middle cerebral arteries (MCAs) were incubated for 24 h with or without kinase inhibitors. Vessel segments were mounted in myographs and the contractile responses to endothelin-1 (ET-1; ETA and ETB receptor agonist) and sarafotoxin 6c (S6c; ETB receptor agonist) were studied. We used real-time PCR to measure the receptor mRNA levels. An ELISA assay showed the activation of ERK1/2 kinases after 3 h. Immunohistochemistry revealed the presence of ETB receptors on the vessels. After organ culture, S6c induced vasoconstriction. Incubation with the MEK/ERK inhibitors U0126 and SB386023 diminished the contractile response to S6c. The p38 MAPK inhibitor SB239063 did not affect the S6c-induced contraction. The ET-1-induced vasoconstriction was increased after incubation with SB386023 or SB239063, while unaffected by U0126. The ETB receptor mRNA levels were diminished by SB386023 and U0126. The ETA receptor mRNA levels were unaffected. The levels of activated ERK1/2 kinases were significantly higher after 3 h of organ culture as compared to fresh vessels. The level of ETB receptor protein on the smooth muscle cells of the MCA, visualised by immunohistochemistry, was somewhat diminished by SB386023. Our results show that the ERK1/2 MAPK is important in the upregulation of contractile ETB receptors in MCA after organ culture. Since there is a similar upregulation in models of focal ischaemia and subarachnoid haemorrhage, this may be an important pathophysiological event. PMID:15237095

  2. Different Epigenetic Alterations Are Associated with Abnormal IGF2/Igf2 Upregulation in Neural Tube Defects

    PubMed Central

    Bai, Baoling; Zhang, Qin; Liu, Xiaozhen; Miao, Chunyue; Shangguan, Shaofang; Bao, Yihua; Guo, Jin; Wang, Li; Zhang, Ting; Li, Huili

    2014-01-01

    The methylation status of DNA methylation regions (DMRs) of the imprinted gene IGF2/Igf2 is associated with neural tube defects (NTDs), which are caused by a failure of the neural tube to fold and close and are the second-most common birth defect; however, the characterization of the expression level of IGF2/Igf2 in neural tissue from human fetuses affected with NTDs remains elusive. More importantly, whether abnormal chromatin structure also influences IGF2/Igf2 expression in NTDs is unclear. Here, we investigated the transcriptional activity of IGF2/Igf2 in normal and NTD spinal cord tissues, the methylation status of different DMRs, and the chromatin structure of the promoter. Our data indicated that in NTD samples from both human fetuses and retinoic acid (RA)-treated mouse fetuses, the expression level of IGF2/Igf2 was upregulated 6.41-fold and 1.84-fold, respectively, compared to controls. H19 DMR1, but not IGF2 DMR0, was hypermethylated in human NTD samples. In NTD mice, h19 DMR1 was stable, whereas the chromatin structure around the promoter of Igf2 might be loosened, which was displayed by higher H3K4 acetylation and lower H3K27 trimethylation. Therefore, the data revealed that IGF2/Igf2 expression can be ectopically up-regulated by dual epigenetic factors in NTDs. In detail, the upregulation of IGF2/Igf2 is likely controlled by hypermethylation of H19 DMR1 in human NTDs, however, in acute external RA-induced NTD mice it is potentially determined by more open chromatin structure. PMID:25423083

  3. Thyroid Hormone Upregulates Zinc-?2-glycoprotein Production in the Liver but Not in Adipose Tissue

    PubMed Central

    Simó, Rafael; Hernández, Cristina; Sáez-López, Cristina; Soldevila, Berta; Puig-Domingo, Manel; Selva, David M.

    2014-01-01

    Overproduction of zinc-?2-glycoprotein by adipose tissue is crucial in accounting for the lipolysis occurring in cancer cachexia of certain malignant tumors. The main aim of this study was to explore whether thyroid hormone could enhance zinc-?2-glycoprotein production in adipose tissue. In addition, the regulation of zinc-?2-glycoprotein by thyroid hormone in the liver was investigated. We performed in vitro (HepG2 cells and primary human adipocytes) and in vivo (C57BL6/mice) experiments addressed to examine the effect of thyroid hormone on zinc-?2-glycoprotein production (mRNA and protein levels) in liver and visceral adipose tissue. We also measured the zinc-?2-glycoprotein serum levels in a cohort of patients before and after controlling their hyperthyroidism. Our results showed that thyroid hormone up-regulates zinc-?2-glycoprotein production in HepG2 cells in a dose-dependent manner. In addition, the zinc-?2-glycoprotein proximal promoter contains functional thyroid hormone receptor binding sites that respond to thyroid hormone treatment in luciferase reporter gene assays in HepG2 cells. Furthermore, zinc-?2-glycoprotein induced lipolysis in HepG2 in a dose-dependent manner. Our in vivo experiments in mice confirmed the up-regulation of zinc-?2-glycoprotein induced by thyroid hormone in the liver, thus leading to a significant increase in zinc-?2-glycoprotein circulating levels. However, thyroid hormone did not regulate zinc-?2-glycoprotein production in either human or mouse adipocytes. Finally, in patients with hyperthyroidism a significant reduction of zinc-?2-glycoprotein serum levels was detected after treatment but was unrelated to body weight changes. We conclude that thyroid hormone up-regulates the production of zinc-?2-glycoprotein in the liver but not in the adipose tissue. The neutral effect of thyroid hormones on zinc-?2-glycoprotein expression in adipose tissue could be the reason why zinc-?2-glycoprotein is not related to weight loss in hyperthyroidism. PMID:24465683

  4. KSHV encoded LANA upregulates Pim-1 and is a substrate for its kinase activity

    SciTech Connect

    Bajaj, Bharat G. [Department of Microbiology and the Tumor Virology Program, Abramson Comprehensive Cancer Center, University of Pennsylvania Medical School, 201E Johnson Pavilion, 3610 Hamilton Walk, Philadelphia, PA 19104 (United States); Verma, Subhash C. [Department of Microbiology and the Tumor Virology Program, Abramson Comprehensive Cancer Center, University of Pennsylvania Medical School, 201E Johnson Pavilion, 3610 Hamilton Walk, Philadelphia, PA 19104 (United States); Lan, Ke [Department of Microbiology and the Tumor Virology Program, Abramson Comprehensive Cancer Center, University of Pennsylvania Medical School, 201E Johnson Pavilion, 3610 Hamilton Walk, Philadelphia, PA 19104 (United States); Cotter, Murray A. [Department of Microbiology and the Tumor Virology Program, Abramson Comprehensive Cancer Center, University of Pennsylvania Medical School, 201E Johnson Pavilion, 3610 Hamilton Walk, Philadelphia, PA 19104 (United States); Woodman, Zenda L. [Department of Microbiology and the Tumor Virology Program, Abramson Comprehensive Cancer Center, University of Pennsylvania Medical School, 201E Johnson Pavilion, 3610 Hamilton Walk, Philadelphia, PA 19104 (United States); Robertson, Erle S. [Department of Microbiology and the Tumor Virology Program, Abramson Comprehensive Cancer Center, University of Pennsylvania Medical School, 201E Johnson Pavilion, 3610 Hamilton Walk, Philadelphia, PA 19104 (United States)]. E-mail: erle@mail.med.upenn.edu

    2006-07-20

    Pim kinases are proto-oncogenes that are upregulated in a number of B cell cancers, including Epstein-Barr Virus (EBV) associated Burkitt's lymphoma. They have also been shown to be upregulated in Kaposi sarcoma-associated herpes virus (KSHV) infected primary B cells. Most cells in KSHV-associated tumors are latently infected and express only a small subset of viral genes, with KSHV latency associated nuclear antigen (LANA) being constitutively expressed. LANA regulates the transcription of a large number of cellular and viral genes. Here, we show that LANA upregulates transcription from the Pim-1 promoter (pPim-1) and map this activation to a region in the promoter located within the sequence (-681 to +37). We show that LANA expressing cells can proliferate faster and are better protected from drug induced apoptosis. Since transition through cell cycle check points and anti-apoptosis are functions associated with Pim-1, it is likely that higher Pim-1 expression in cells expressing LANA is responsible, at least in part, for this effect. A Pim-1 phosphorylation site was also identified within the amino-terminal domain of LANA. Using in vitro kinase assays, we confirmed that LANA was indeed a Pim-1 substrate, and the failure of Pim-1 to phosphorylate LANA mutated at SS205/6RR identified this site as the specific serine residues phosphorylated by Pim-1. This report provides valuable insight into yet another cellular signaling pathway subverted by KSHV LANA and suggests a contribution to KSHV related oncogenesis.

  5. Thyroid hormone upregulates zinc-?2-glycoprotein production in the liver but not in adipose tissue.

    PubMed

    Simó, Rafael; Hernández, Cristina; Sáez-López, Cristina; Soldevila, Berta; Puig-Domingo, Manel; Selva, David M

    2014-01-01

    Overproduction of zinc-?2-glycoprotein by adipose tissue is crucial in accounting for the lipolysis occurring in cancer cachexia of certain malignant tumors. The main aim of this study was to explore whether thyroid hormone could enhance zinc-?2-glycoprotein production in adipose tissue. In addition, the regulation of zinc-?2-glycoprotein by thyroid hormone in the liver was investigated. We performed in vitro (HepG2 cells and primary human adipocytes) and in vivo (C57BL6/mice) experiments addressed to examine the effect of thyroid hormone on zinc-?2-glycoprotein production (mRNA and protein levels) in liver and visceral adipose tissue. We also measured the zinc-?2-glycoprotein serum levels in a cohort of patients before and after controlling their hyperthyroidism. Our results showed that thyroid hormone up-regulates zinc-?2-glycoprotein production in HepG2 cells in a dose-dependent manner. In addition, the zinc-?2-glycoprotein proximal promoter contains functional thyroid hormone receptor binding sites that respond to thyroid hormone treatment in luciferase reporter gene assays in HepG2 cells. Furthermore, zinc-?2-glycoprotein induced lipolysis in HepG2 in a dose-dependent manner. Our in vivo experiments in mice confirmed the up-regulation of zinc-?2-glycoprotein induced by thyroid hormone in the liver, thus leading to a significant increase in zinc-?2-glycoprotein circulating levels. However, thyroid hormone did not regulate zinc-?2-glycoprotein production in either human or mouse adipocytes. Finally, in patients with hyperthyroidism a significant reduction of zinc-?2-glycoprotein serum levels was detected after treatment but was unrelated to body weight changes. We conclude that thyroid hormone up-regulates the production of zinc-?2-glycoprotein in the liver but not in the adipose tissue. The neutral effect of thyroid hormones on zinc-?2-glycoprotein expression in adipose tissue could be the reason why zinc-?2-glycoprotein is not related to weight loss in hyperthyroidism. PMID:24465683

  6. Heme oxygenase-1 upregulation modulates tone and fibroelastic properties of internal anal sphincter.

    PubMed

    Krishna, Chadalavada Vijay; Singh, Jagmohan; Kumar, Sumit; Rattan, Satish

    2014-09-15

    A compromise in the internal anal sphincter (IAS) tone and fibroelastic properties (FEP) plays an important role in rectoanal incontinence. Herein, we examined the effects of heme oxygenase (HO)-1 upregulation on these IAS characteristics in young rats. We determined the effect of HO-1 upregulator hemin on HO-1 mRNA and protein expressions and on basal IAS tone and its FEP before and after HO-1 inhibitor tin protoporphyrin IX. For FEP, we determined the kinetics of the IAS smooth muscle responses, by the velocities of relaxation, and recovery of the IAS tone following 0 Ca(2+) and electrical field stimulation. To characterize the underlying signal transduction for these changes, we determined the effects of hemin on RhoA-associated kinase (RhoA)/Rho kinase (ROCK) II, myosin-binding subunit of myosin light chain phosphatase 1, fibronectin, and elastin expression levels. Hemin increased HO-1 mRNA and protein similar to the increases in the basal tone, and in the FEP of the IAS. Underlying mechanisms in the IAS characteristics are associated with increases in the genetic and translational expressions of RhoA/ROCKII, and elastin. Fibronectin expression levels on the other hand were found to be decreased following HO-1 upregulation. The results of our study show that the hemin/HO-1 system regulates the tone and FEP of IAS. The hemin/HO-1 system thus provides a potential target for the development of new interventions aimed at treatment of gastrointestinal motility disorders, specifically the age-related IAS dysfunction. PMID:25035109

  7. Hes1 promotes blast crisis in chronic myelogenous leukemia through MMP-9 upregulation in leukemic cells.

    PubMed

    Nakahara, Fumio; Kitaura, Jiro; Uchida, Tomoyuki; Nishida, Chiemi; Togami, Katsuhiro; Inoue, Daichi; Matsukawa, Toshihiro; Kagiyama, Yuki; Enomoto, Yutaka; Kawabata, Kimihito C; Chen-Yi, Lai; Komeno, Yukiko; Izawa, Kumi; Oki, Toshihiko; Nagae, Genta; Harada, Yuka; Harada, Hironori; Otsu, Makoto; Aburatani, Hiroyuki; Heissig, Beate; Hattori, Koichi; Kitamura, Toshio

    2014-06-19

    High levels of HES1 expression are frequently found in BCR-ABL(+) chronic myelogenous leukemia in blast crisis (CML-BC). In mouse bone marrow transplantation (BMT) models, co-expression of BCR-ABL and Hes1 induces CML-BC-like disease; however, the underlying mechanism remained elusive. Here, based on gene expression analysis, we show that MMP-9 is upregulated by Hes1 in common myeloid progenitors (CMPs). Analysis of promoter activity demonstrated that Hes1 upregulated MMP-9 by activating NF-?B. Analysis of 20 samples from CML-BC patients showed that MMP-9 was highly expressed in three, with two exhibiting high levels of HES1 expression. Interestingly, MMP-9 deficiency impaired the cobblestone area-forming ability of CMPs expressing BCR-ABL and Hes1 that were in conjunction with a stromal cell layer. In addition, CMPs expressing BCR-ABL and Hes1 secreted MMP-9, promoting the release of soluble Kit-ligand (sKitL) from stromal cells, thereby enhancing proliferation of the leukemic cells. In accordance, mice transplanted with CMPs expressing BCR-ABL and Hes1 exhibited high levels of sKitL as well as MMP-9 in the serum. Importantly, MMP-9 deficiency impaired the development of CML-BC-like disease induced by BCR-ABL and Hes1 in mouse BMT models. The present results suggest that Hes1 promotes the development of CML-BC, partly through MMP-9 upregulation in leukemic cells. PMID:24825862

  8. Reciprocal upregulation of Notch signaling molecules in hematopoietic progenitor and mesenchymal stromal cells

    PubMed Central

    Kikuchi, Y; Kume, A; Urabe, M; Mizukami, H; Suzuki, T; Ozaki, K; Nagai, T; Ozawa, K

    2011-01-01

    Although mesenchymal stem cells (MSCs) play pivotal supportive roles in hematopoiesis, how they interact with hematopoietic stem cells (HSCs) is not well understood. We investigated the interaction between HSCs and surrogate MSCs (C3H10T1/2 stromal cells), focusing on the molecular events induced by cell contact of these bipartite populations. C3H10T1/2 is a mesenchymal stromal cell line that can be induced to differentiate into preadipocytes (A54) and myoblasts (M1601). The stromal cell derivatives were cocultured with murine HSCs (Lineage-Sca1+), and gene expression profiles in stromal cells and HSCs were compared before and after the coculture. HSCs gave rise to cobblestone areas only on A54 cells, with ninefold more progenitors than on M1601 or undifferentiated C3H10T1/2 cells. Microarray-based screening and a quantitative reverse transcriptase directed-polymerase chain reaction showed that the levels of Notch ligands (Jagged1 and Delta-like 3) were increased in A54 cells upon interaction with HSCs. On the other hand, the expression of Notch1 and Hes1 was upregulated in the HSCs cocultured with A54 cells. A transwell assay revealed that the reciprocal upregulation was dependent on cell-to-cell contact. The result suggested that in the hematopoietic niche, HSCs help MSCs to produce Notch ligands, and in turn, MSCs help HSCs to express Notch receptor. Such a reciprocal upregulation would reinforce the downstream signaling to determine the fate of hematopoietic cell lineage. Clarification of the initiating events on cell contact should lead to the identification of specific molecular targets to facilitate HSC engraftment in transplantation therapy. PMID:24693172

  9. Up-regulation of the chemokine CCL21 in the skin of subjects exposed to irritants

    PubMed Central

    Eberhard, Yanina; Ortiz, Susana; Ruiz Lascano, Alejandro; Kuznitzky, Raquel; Serra, Horacio Marcelo

    2004-01-01

    Background Expression of murine CCL21 by dermal lymphatic endothelial cells (LEC) has been demonstrated to be one of the most important steps in Langerhans cell emigration from skin. Previously, our group and others have found that this chemokine is up-regulated in different human inflammatory skin diseases mediated by diverse specific immune responses. This study was carried out to investigate the involvement of CCL21 in human skin after challenge with irritant agents responsible for inducing Irritant Contact Dermatitis (ICD). Results Eleven normal individuals were challenged with different chemical or physical irritants. Two patients with Allergic Contact Dermatitis (ACD) were also challenged with the relevant antigen in order to have a positive control for CCL21 expression. Macroscopic as well as microscopic responses were evaluated. We observed typical ICD responses with mostly mononuclear cells in perivascular areas, but a predominance of polymorphonuclear cells away from the inflamed blood vessels and in the epidermis at 24 hours. Immunohistochemical studies showed up-regulation of CCL21 by lymphatic endothelial cells in all the biopsies taken from ICD and ACD lesions compared to normal skin. Kinetic study at 10, 48, 96 and 168 hours after contact with a classical irritant (sodium lauryl sulphate) showed that the expression of CCL21 was increased in lymphatic vessels at 10 hours, peaked at 48 hours, and then gradually declined. There was a strong correlation between CCL21 expression and the macroscopic response (r = 0.69; p = 0.0008), but not between CCL21 and the number of infiltrating cells in the lesions. Conclusions These results provide new evidence for the role of CCL21 in inflammatory processes. Since the up-regulation of this chemokine was observed in ICD and ACD, it is tempting to speculate that this mechanism operates independently of the type of dermal insult, facilitating the emigration of CCR7+ cells. PMID:15109401

  10. DNA stabilization by the upregulation of estrogen signaling in BRCA gene mutation carriers

    PubMed Central

    Suba, Zsuzsanna

    2015-01-01

    Currently available scientific evidence erroneously suggests that mutagenic weakness or loss of the BRCA1/2 genes may liberate the proliferative effects of estrogen signaling, which provokes DNA damage and genomic instability. Conversely, BRCA mutation seems to be an imbalanced defect, crudely inhibiting the upregulation of estrogen receptor expression and liganded transcriptional activity, whereas estrogen receptor-repressor functions become predominant. In BRCA-proficient cases, estrogen signaling orchestrates the activity of cell proliferation and differentiation with high safety, while upregulating the expression and DNA-stabilizing impact of BRCA genes. In turn, BRCA proteins promote estrogen signaling by proper estrogen synthesis via CYP19 gene regulation and by induction of the appropriate expression and transcriptional activity of estrogen receptors. In this exquisitely organized regulatory system, the dysfunction of each player may jeopardize genome stability and lead to severe chronic diseases, such as cancer development. Female organs, such as breast, endometrium, and ovary, exhibiting regular cyclic proliferative activity are particularly vulnerable in case of disturbances in either estrogen signaling or BRCA-mediated DNA repair. BRCA mutation carrier women may apparently be healthy or exhibit clinical signs of deficient estrogen signaling in spite of hyperestrogenism. Even women who enjoy sufficient compensatory DNA-defending activities are at risk of tumor development because many endogenous and environmental factors may jeopardize the mechanisms of extreme compensatory processes. Natural estrogens have numerous benefits in tumor prevention and therapy even in BRCA mutation carriers. There are no toxic effects even in sky-high doses and all physiologic cellular functions are strongly upregulated, while malignant tumor cells are recognized and killed in a Janus-faced manner. PMID:26028963

  11. PTEN induces apoptosis and cavitation via HIF-2-dependent Bnip3 upregulation during epithelial lumen formation.

    PubMed

    Qi, Y; Liu, J; Saadat, S; Tian, X; Han, Y; Fong, G-H; Pandolfi, P P; Lee, L Y; Li, S

    2015-05-01

    The tumor suppressor phosphatase and tensin homolog (PTEN) dephosphorylates PIP3 and antagonizes the prosurvival PI3K-Akt pathway. Targeted deletion of PTEN in mice led to early embryonic lethality. To elucidate its role in embryonic epithelial morphogenesis and the underlying mechanisms, we used embryonic stem cell-derived embryoid body (EB), an epithelial cyst structurally similar to the periimplantation embryo. PTEN is upregulated during EB morphogenesis in parallel with apoptosis of core cells, which mediates EB cavitation. Genetic ablation of PTEN causes Akt overactivation, apoptosis resistance and cavitation blockade. However, rescue experiments using mutant PTEN and pharmacological inhibition of Akt suggest that the phosphatase activity of PTEN and Akt are not involved in apoptosis-mediated cavitation. Instead, hypoxia-induced upregulation of Bnip3, a proapoptotic BH3-only protein, mediates PTEN-dependent apoptosis and cavitation. PTEN inactivation inhibits hypoxia- and reactive oxygen species-induced Bnip3 elevation. Overexpression of Bnip3 in PTEN-null EBs rescues apoptosis of the core cells. Mechanistically, suppression of Bnip3 following PTEN loss is likely due to reduction of hypoxia-inducible factor-2? (HIF-2?) because forced expression of an oxygen-stable HIF-2? mutant rescues Bnip3 expression and apoptosis. Lastly, we show that HIF-2? is upregulated by PTEN at both transcriptional and posttranscriptional levels. Ablation of prolyl hydroxylase domain-containing protein 2 (PHD2) in normal EBs or inhibition of PHD activities in PTEN-null EBs stabilizes HIF-2? and induces Bnip3 and caspase-3 activation. Altogether, these results suggest that PTEN is required for apoptosis-mediated cavitation during epithelial morphogenesis by regulating the expression of HIF-2? and Bnip3. PMID:25394489

  12. Different epigenetic alterations are associated with abnormal IGF2/Igf2 upregulation in neural tube defects.

    PubMed

    Bai, Baoling; Zhang, Qin; Liu, Xiaozhen; Miao, Chunyue; Shangguan, Shaofang; Bao, Yihua; Guo, Jin; Wang, Li; Zhang, Ting; Li, Huili

    2014-01-01

    The methylation status of DNA methylation regions (DMRs) of the imprinted gene IGF2/Igf2 is associated with neural tube defects (NTDs), which are caused by a failure of the neural tube to fold and close and are the second-most common birth defect; however, the characterization of the expression level of IGF2/Igf2 in neural tissue from human fetuses affected with NTDs remains elusive. More importantly, whether abnormal chromatin structure also influences IGF2/Igf2 expression in NTDs is unclear. Here, we investigated the transcriptional activity of IGF2/Igf2 in normal and NTD spinal cord tissues, the methylation status of different DMRs, and the chromatin structure of the promoter. Our data indicated that in NTD samples from both human fetuses and retinoic acid (RA)-treated mouse fetuses, the expression level of IGF2/Igf2 was upregulated 6.41-fold and 1.84-fold, respectively, compared to controls. H19 DMR1, but not IGF2 DMR0, was hypermethylated in human NTD samples. In NTD mice, h19 DMR1 was stable, whereas the chromatin structure around the promoter of Igf2 might be loosened, which was displayed by higher H3K4 acetylation and lower H3K27 trimethylation. Therefore, the data revealed that IGF2/Igf2 expression can be ectopically up-regulated by dual epigenetic factors in NTDs. In detail, the upregulation of IGF2/Igf2 is likely controlled by hypermethylation of H19 DMR1 in human NTDs, however, in acute external RA-induced NTD mice it is potentially determined by more open chromatin structure. PMID:25423083

  13. Evidence That Up-Regulation of MicroRNA-29 Contributes to Postnatal Body Growth Deceleration.

    PubMed

    Kamran, Fariha; Andrade, Anenisia C; Nella, Aikaterini A; Clokie, Samuel J; Rezvani, Geoffrey; Nilsson, Ola; Baron, Jeffrey; Lui, Julian C

    2015-06-01

    Body growth is rapid in infancy but subsequently slows and eventually ceases due to a progressive decline in cell proliferation that occurs simultaneously in multiple organs. We previously showed that this decline in proliferation is driven in part by postnatal down-regulation of a large set of growth-promoting genes in multiple organs. We hypothesized that this growth-limiting genetic program is orchestrated by microRNAs (miRNAs). Bioinformatic analysis identified target sequences of the miR-29 family of miRNAs to be overrepresented in age-down-regulated genes. Concomitantly, expression microarray analysis in mouse kidney and lung showed that all members of the miR-29 family, miR-29a, -b, and -c, were strongly up-regulated from 1 to 6 weeks of age. Real-time PCR confirmed that miR-29a, -b, and -c were up-regulated with age in liver, kidney, lung, and heart, and their expression levels were higher in hepatocytes isolated from 5-week-old mice than in hepatocytes from embryonic mouse liver at embryonic day 16.5. We next focused on 3 predicted miR-29 target genes (Igf1, Imp1, and Mest), all of which are growth-promoting. A 3'-untranslated region containing the predicted target sequences from each gene was placed individually in a luciferase reporter construct. Transfection of miR-29 mimics suppressed luciferase gene activity for all 3 genes, and this suppression was diminished by mutating the target sequences, suggesting that these genes are indeed regulated by miR-29. Taken together, the findings suggest that up-regulation of miR-29 during juvenile life drives the down-regulation of multiple growth-promoting genes, thus contributing to physiological slowing and eventual cessation of body growth. PMID:25866874

  14. Peripheral challenge with a viral mimic upregulates expression of the complement genes in the hippocampus.

    PubMed

    Michalovicz, Lindsay T; Lally, Brent; Konat, Gregory W

    2015-08-15

    Peripheral challenge with a viral mimetic, polyinosinic-polycytidylic acid (PIC) induces hippocampal hyperexcitability in mice. Here, we characterized this hippocampal response through a whole genome transcriptome analysis. Intraperitoneal injection of PIC resulted in temporal dysregulation of 625 genes in the hippocampus, indicating an extensive genetic reprogramming. The bioinformatics analysis of these genes revealed the complement pathway to be the most significantly activated. The gene encoding complement factor B (CfB) exhibited the highest response, and its upregulation was commensurate with the development of hyperexcitability. Collectively, these results suggest that the induction of hippocampal hyperexcitability may be mediated by the alternative complement cascades. PMID:26198930

  15. Localization and upregulation of survivin in cancer health disparities: a clinical perspective

    PubMed Central

    Khan, Salma; Ferguson Bennit, Heather; Asuncion Valenzuela, Malyn May; Turay, David; Diaz Osterman, Carlos J; Moyron, Ron B; Esebanmen, Grace E; Ashok, Arjun; Wall, Nathan R

    2015-01-01

    Survivin is one of the most important members of the inhibitors of apoptosis protein family, as it is expressed in most human cancers but is absent in normal, differentiated tissues. Lending to its importance, survivin has proven associations with apoptosis and cell cycle control, and has more recently been shown to modulate the tumor microenvironment and immune evasion as a result of its extracellular localization. Upregulation of survivin has been found in many cancers including breast, prostate, pancreatic, and hematological malignancies, and it may prove to be associated with the advanced presentation, poorer prognosis, and lower survival rates observed in ethnically diverse populations. PMID:26185415

  16. Protective effects of lazaroid U74389F (16-desmethyl tirilazad) on endrin-induced lipid peroxidation and DNA damage in brain and liver and regional distribution of catalase activity in rat brain.

    PubMed

    Bagchi, M; Ghosh, S; Bagchi, D; Hassoun, E; Stohs, S J

    1995-12-01

    Endrin, a poly-halogenated cyclic hydrocarbon, induces hepatic lipid peroxidation, modulates calcium homeostasis, decreases membrane fluidity, and increases nuclear DNA damage. Little information is available on the neurotoxicity of endrin. The effects of endrin on lipid peroxidation, DNA damage, and regional distribution of catalase activity were assessed in rat brain and liver 24 h following an acute oral dose of 4.5 mg endrin/kg. Lipid peroxidation associated with whole brain mitochondria increased 2.4-fold, whereas microsomal lipid peroxidation increased 2.8-fold following endrin administration. Lipid peroxidation also increased 2.0-fold both in hepatic mitochondria and microsomes. Catalase activity decreased 24% in the hypothalamus, 23% in the cortex, 38% in the cerebellum, and 11% in the brain stem in response to endrin. A 4.3-fold increase in brain nuclear DNA-single strand breaks (SSB) was observed in endrin-treated rats. Pretreatment of rats intraperitoneally with the lazaroid U74389F (16-desmethyl tirilazad) (10 mg/kg in two doses) attenuated the biochemical consequences of endrin-induced oxidative stress. The administration of U74389F in citrate buffer (pH 3.8) provided better protection than administering the lazaroid in corn oil, decreasing endrin-induced lipid peroxidation by 50-80% and DNA-SSB by approximately 72% in liver and 85% in brain, while ameliorating the suppressed catalase activity. The data suggest an involvement of an oxidative stress in the neurotoxicity and hepatotoxicity induced by endrin, which can be attenuated by the lazaroid U74389F. PMID:8582661

  17. An Ancient Relative of Cyclooxygenase in Cyanobacteria Is a Linoleate 10S-Dioxygenase That Works in Tandem with a Catalase-related Protein with Specific 10S-Hydroperoxide Lyase Activity*

    PubMed Central

    Brash, Alan R.; Niraula, Narayan P.; Boeglin, William E.; Mashhadi, Zahra

    2014-01-01

    In the course of exploring the scope of catalase-related hemoprotein reactivity toward fatty acid hydroperoxides, we detected a novel candidate in the cyanobacterium Nostoc punctiforme PCC 73102. The immediate neighboring upstream gene, annotated as “cyclooxygenase-2,” appeared to be a potential fatty acid heme dioxygenase. We cloned both genes and expressed the cDNAs in Escherichia coli, confirming their hemoprotein character. Oxygen electrode recordings demonstrated a rapid (>100 turnovers/s) reaction of the heme dioxygenase with oleic and linoleic acids. HPLC, including chiral column analysis, UV, and GC-MS of the oxygenated products, identified a novel 10S-dioxygenase activity. The catalase-related hemoprotein reacted rapidly and specifically with linoleate 10S-hydroperoxide (>2,500 turnovers/s) with a hydroperoxide lyase activity specific for the 10S-hydroperoxy enantiomer. The products were identified by NMR as (8E)10-oxo-decenoic acid and the C8 fragments, 1-octen-3-ol and 2Z-octen-1-ol, in ?3:1 ratio. Chiral HPLC analysis established strict enzymatic control in formation of the 3R alcohol configuration (99% enantiomeric excess) and contrasted with racemic 1-octen-3-ol formed in reaction of linoleate 10S-hydroperoxide with hematin or ferrous ions. The Nostoc linoleate 10S-dioxygenase, the sequence of which contains the signature catalytic sequence of cyclooxygenases and fungal linoleate dioxygenases (YRWH), appears to be a heme dioxygenase ancestor. The novel activity of the lyase expands the known reactions of catalase-related proteins and functions in Nostoc in specific transformation of the 10S-hydroperoxylinoleate. PMID:24659780

  18. Nicotine exploits a COPI-mediated process for chaperone-mediated up-regulation of its receptors

    PubMed Central

    Henderson, Brandon J.; Srinivasan, Rahul; Nichols, Weston A.; Dilworth, Crystal N.; Gutierrez, Diana F.; Mackey, Elisha D.W.; McKinney, Sheri; Drenan, Ryan M.; Richards, Christopher I.

    2014-01-01

    Chronic exposure to nicotine up-regulates high sensitivity nicotinic acetylcholine receptors (nAChRs) in the brain. This up-regulation partially underlies addiction and may also contribute to protection against Parkinson’s disease. nAChRs containing the ?6 subunit (?6* nAChRs) are expressed in neurons in several brain regions, but comparatively little is known about the effect of chronic nicotine on these nAChRs. We report here that nicotine up-regulates ?6* nAChRs in several mouse brain regions (substantia nigra pars compacta, ventral tegmental area, medial habenula, and superior colliculus) and in neuroblastoma 2a cells. We present evidence that a coat protein complex I (COPI)-mediated process mediates this up-regulation of ?6* or ?4* nAChRs but does not participate in basal trafficking. We show that ?6?2?3 nAChR up-regulation is prevented by mutating a putative COPI-binding motif in the ?3 subunit or by inhibiting COPI. Similarly, a COPI-dependent process is required for up-regulation of ?4?2 nAChRs by chronic nicotine but not for basal trafficking. Mutation of the putative COPI-binding motif or inhibition of COPI also results in reduced normalized Förster resonance energy transfer between ?6?2?3 nAChRs and ?COP subunits. The discovery that nicotine exploits a COPI-dependent process to chaperone high sensitivity nAChRs is novel and suggests that this may be a common mechanism in the up-regulation of nAChRs in response to chronic nicotine. PMID:24378908

  19. Cyclic stretch induces upregulation of endothelin-1 with keratinocytes in vitro: Possible role in mechanical stress-induced hyperpigmentation

    SciTech Connect

    Kurita, Masakazu, E-mail: masakazukurita@gmail.com [Department of Plastic Surgery, Kyorin University School of Medicine, 6-20-2 Shinkawa, Mitaka-shi, Tokyo 181-8611 (Japan)] [Department of Plastic Surgery, Kyorin University School of Medicine, 6-20-2 Shinkawa, Mitaka-shi, Tokyo 181-8611 (Japan); Okazaki, Mutsumi [Department of Plastic and Reconstructive Surgery, Graduate School, Tokyo Medical and Dental University, 1-5-45 Yushima, Bunkyo-ku, Tokyo 113-8510 (Japan)] [Department of Plastic and Reconstructive Surgery, Graduate School, Tokyo Medical and Dental University, 1-5-45 Yushima, Bunkyo-ku, Tokyo 113-8510 (Japan); Fujino, Takashi [Department of Pathology, Kyorin University School of Medicine, 6-20-2 Shinkawa, Mitaka-shi, Tokyo 181-8611 (Japan)] [Department of Pathology, Kyorin University School of Medicine, 6-20-2 Shinkawa, Mitaka-shi, Tokyo 181-8611 (Japan); Takushima, Akihiko; Harii, Kiyonori [Department of Plastic Surgery, Kyorin University School of Medicine, 6-20-2 Shinkawa, Mitaka-shi, Tokyo 181-8611 (Japan)] [Department of Plastic Surgery, Kyorin University School of Medicine, 6-20-2 Shinkawa, Mitaka-shi, Tokyo 181-8611 (Japan)

    2011-05-27

    Highlights: {yields} Influence of cyclic stretch on melanogenetic paracrine cytokines was investigated. {yields} Keratinocyte-derived endothelin-1 was upregulated with cyclic stretch. {yields} Degree of upregulation increases dose-dependently. {yields} This upregulation possibly plays a role in the pathogenesis of pigmented disorders. -- Abstract: The aim of this study was to investigate the possible pathological relation between mechanical stress and hyperpigmentation. We did this by investigating the influence of cyclic stretch on the expression of keratinocyte- and fibroblast-derived melanogenetic paracrine cytokines in vitro. Using primary human keratinocytes and fibroblasts, alterations of mRNA expression of melanogenetic paracrine cytokines due to cyclic stretch were investigated using a real-time polymerase chain reaction (PCR). The cytokines included basic fibroblast growth factor (bFGF), stem cell factor (SCF), granulocyte/macrophage colony-stimulating factor, interleukin-1{alpha}, and endothelin-1 (ET-1) for keratinocytes and bFGF, SCF, and hepatocyte growth factor for fibroblasts. The dose dependence of keratinocyte-derived ET-1 upregulation was further investigated using real-time PCR and an enzyme-linked immunosorbent assay. We also investigated the effects of cyclic stretch on the proliferation and differentiation of keratinocytes. Among the melanogenetic paracrine cytokines investigated, keratinocyte-derived ET-1 was consistently upregulated in all four cell lines. The degree of upregulation increased with the degree of the length and frequency of the stretch; in contrast, cell number and differentiation markers showed no obvious alterations with cyclic stretch. Keratinocyte-derived ET-1 upregulation possibly plays a significant role in the pathogenesis of pigmented disorders, such as friction melanosis, caused by mechanical stress.

  20. AMPA receptor upregulation in the nucleus accumbens shell of cocaine-sensitized rats depends upon S-nitrosylation of stargazin

    PubMed Central

    Milovanovic, Mike; Park, Diana J.; West, Anthony R.; Snyder, Solomon H.; Wolf, Marina E.

    2014-01-01

    Behavioral sensitization to cocaine is associated with increased AMPA receptor (AMPAR) surface expression in the nucleus accumbens (NAc). This upregulation is withdrawal-dependent, as it is not detected on withdrawal day (WD) 1, but is observed on WD7–21. Its underlying mechanisms have not been clearly established. Nitric oxide (NO) regulates AMPAR trafficking in the brain by S-nitrosylation of the AMPAR auxiliary subunit, stargazin, leading to increased AMPAR surface expression. Our goal was to determine if stargazin S-nitrosylation contributes to AMPAR upregulation during sensitization. First, we measured stargazin S-nitrosylation in NAc core and shell subregions on WD14 after 8 daily injections of saline or 15mg/kg cocaine. Stargazin S-nitrosylation was markedly increased in NAc shell but not core. To determine if this is associated with AMPAR upregulation, rats received 8 cocaine or saline injections followed by twice-daily treatments with vehicle or the nitric oxide synthase inhibitor L-NAME (50mg/kg) on WD1–6, the time when AMPAR upregulation is developing in cocaine-exposed rats. Cocaine/vehicle rats showed elevated stargazin and GluA1 surface expression on WD7 compared to saline/vehicle rats; the GluA1 increase was more robust in core, while stargazin increased more robustly in shell. These effects of cocaine were attenuated in shell but not core when cocaine injections were followed by L-NAME treatment on WD1–6. Together, these results indicate that elevated S-nitrosylation of stargazin contributes to AMPAR upregulation during sensitization selectively in the NAc shell. It is possible that AMPAR upregulation in core involves a different TARP, ?4, which also upregulates in the NAc of sensitized rats. PMID:24035918

  1. HDAC5 promotes colorectal cancer cell proliferation by up-regulating DLL4 expression

    PubMed Central

    He, Ping; Liang, Jiexiong; Shao, Tiansong; Guo, Yang; Hou, Yingchen; Li, Yang

    2015-01-01

    The histone deacetylase (HDACs) family contains a family of enzymes, which are involved in modulating a wide range of cellular processes, such as proliferation, differentiation, apoptosis, and cell cycle progression. However, the biological function of HDAC5 in colorectal cancer has not been well established. In the current research, our data showed that the mRNA and protein levels of HDAC5 were up-regulated in human colorectal cancer cell lines. CCK-8 assay showed that overexpression of HDAC5 significantly promoted the proliferation of colorectal cancer cell lines including SW480 and HCT116. On the contrary, HDAC5 knockdown using small interfering RNA suppressed cell growth in colorectal tumor cells. At the molecular level, we demonstrated that HDAC5 promoted the expression of DLL4. In addition, down-regulation of DLL4 diminished the proliferative effects of HDAC5 in human colorectal cancer cells. Taken together, these results suggest that HDAC5 elevates the proliferation of colorectal cancer cells through up-regulation of DLL4. The current study might provide novel potential therapeutic targets in the treatment of colorectal cancer.

  2. Triptolide induces apoptosis through the SERCA 3 upregulation in PC12 cells.

    PubMed

    Krizanova, Olga; Markova, Jana; Pacak, Karel; Skultety, Ludovit; Soltysova, Andrea; Hudecova, Sona

    2014-01-01

    Diterpenoid triepoxide - Triptolide (TTL) - increased protein levels of the noradrenaline transporter in three pheochromocytoma cell lines. This transporter is involved in the apoptosis induction through the inhibition of a transcription factor NF-kappa B. Nevertheless, calcium release from the endoplasmic reticulum can also induce inner mitochondrial pathway of apoptosis in variety of cells. Therefore, the aim of this work was to evaluate an involvement of calcium and, more specifically, the intracellular calcium transport systems in the apoptosis induction in pheochrocytoma cell line PC12. We observed significantly increased amount of reticular calcium in TTL-treated cells compared to control, untreated cells. Surprisingly, gene expression of the IP3 receptors was not changed after the TTL treatment, but ryanodine receptor of the type 2 (RyR2) was downregulated and sarco/endoplasmic reticulum calcium ATPase type 3 (SERCA 3) was upregulated in TTL- treated cells, compared to untreated controls. SERCA 3 blocking with the specific blocker thapsigargin prevented increase in apoptosis observed by the TTL treatment. Decrease in the ATP production by a replacement of glucose in the cultivation medium for its nonutilizable analog 2-deoxyglucose also prevented induction of the apoptosis in TTL-treated PC12 cells. Thus, these results suggest that upregulation of the SERCA 3 is ultimately involved in the TTL-induced apoptosis in PC12 cells. PMID:24448368

  3. Interleukin-10 inhibits lipopolysaccharide-induced upregulation of tissue factor in canine peripheral blood monocytes.

    PubMed

    Ogasawara, Seigo; Stokol, Tracy

    2012-08-15

    The potentially fatal hemostatic disorder of disseminated intravascular coagulation (DIC) is initiated in bacterial sepsis by lipopolysaccharide (LPS)-induced tissue factor (TF) expression on monocytes. Interleukin-10 (IL-10) is a potent inhibitory cytokine that downregulates monocyte inflammatory and procoagulant responses. We hypothesized that canine recombinant IL-10 (rIL-10) would inhibit LPS-induced TF upregulation on canine monocytes in a dose-dependent manner. Canine peripheral blood mononuclear cells (PBMC), obtained by double-density gradient centrifugation, and monocytes, purified from PBMC by immunomagnetic bead separation with an anti-canine CD14 antibody (Ab), were stimulated in suspension with LPS (0.1-1000 ng/mL) for various times. Recombinant IL-10 (10-5000 pg/mL) was added with LPS or up to 2h later. Tissue factor procoagulant activity was measured by cleavage of a chromogenic substrate by activated Factor X generated by the TF-factor VII complex. We found that rIL-10, when given concurrently or 1h after LPS, strongly inhibited LPS-induced TF procoagulant activity in canine PBMC and monocytes. This inhibition was dose-dependent and blocked by an anti-canine IL-10 Ab. Our results indicate that rIL-10 effectively inhibits LPS-induced TF upregulation in canine monocytes and could potentially be useful in limiting the development of DIC in dogs with endotoxemia. PMID:22609246

  4. Cornus officinalis Methanol Extract Upregulates Melanogenesis in Melan-a Cells

    PubMed Central

    Hwang, Ji Yeon; Lee, Jae Soon; Kim, Young Chul

    2015-01-01

    Cornus officinalis is widely distributed in Korea, and its fruit has been used to make as herbal drug for traditional medicine in Korea, Japan, and China because of its tonic, analgesic, and diuretic properties. However, the effects of C. officinalis methanol extract (COME) on melanogenesis remain poorly understood. We evaluated the melanogenic capability of COME in melan-a cells, which are immortalized mouse melanocytes. COME increased melanin synthesis in a dose-dependent manner. Treatment with 12.5 ?g/mL of COME significantly increased melanin content by 36.1% (p < 0.001) to a level even higher than that (31.6%) of 3-isobutyl-1-methyl-xanthine, a well-known pigmentation agent. COME also upregulated tyrosinase activity and its messenger RNA and protein expression. In addition, COME upregulated the expression of tyrosinase-related proteins 1 and 2 and microphthalmia-associated transcription factor-M messenger RNA expression. These results imply that COME may be appropriate for development as a natural product to treat hair graying.

  5. Upregulation of human ?-defensin-3 and cathelicidin LL-37 in Kaposi’s sarcoma

    PubMed Central

    Fathy, Hanan

    2012-01-01

    Background: Kaposi’s sarcoma (KS) is a rare neoplasm of lymphatic endothelial cells. Human herpes virus 8 (HHV-8) is considered to be a necessary, but not sufficient causal agent of KS and additional cofactors remain unknown. In this study we evaluated the expression of human ? defensin (HBD)-3 and LL-37 in cutaneous lesions of KS in comparison to the healthy skin of normal subjects. Methods: We performed a quantitative immunohistochemical study of HBD-3 and LL-37 on skin lesions from 18 patients having KS, and on healthy skin from 12 normal controls. Results: HBD-3 and LL-37 were significantly upregulated in epidermal and dermal specimens of all KS patients in comparison to normal skin of healthy controls. The immunostaining score of dermal HBD-3 was significantly higher in nodular lesions (9.6 ± 2.4) versus plaque lesions (4.1 ± 2.2), P = 0.001. Also the immunostaining score of dermal LL-37 was significantly higher in nodular lesions versus plaque lesions (P = 0.001). Conclusions: We have demonstrated for the first time that HBD-3 and LL-37 are significantly upregulated in lesional skin of KS in comparison to the skin of healthy controls. The obtained data suggest a possible involvement of these antimicrobial peptides in the pathogenesis of KS. However, the biological significance of HBD-3 and LL-37 in KS lesions needs further research. PMID:24358820

  6. p75NTR, but not proNGF, is upregulated following status epilepticus in mice.

    PubMed

    VonDran, Melissa W; LaFrancois, John; Padow, Victoria A; Friedman, Wilma J; Scharfman, Helen E; Milner, Teresa A; Hempstead, Barbara L

    2014-01-01

    ProNGF and p75(NTR) are upregulated and induce cell death following status epilepticus (SE) in rats. However, less is known about the proneurotrophin response to SE in mice, a more genetically tractable species where mechanisms can be more readily dissected. We evaluated the temporal- and cell-specific induction of the proneurotrophins and their receptors, including p75(NTR), sortilin, and sorCS2, following mild SE induced with kainic acid (KA) or severe SE induced by pilocarpine. We found that mature NGF, p75(NTR), and proBDNF were upregulated following SE, while proNGF was not altered, indicating potential mechanistic differences between rats and mice. ProBDNF was localized to mossy fibers and microglia following SE. p75(NTR) was transiently induced primarily in axons and axon terminals following SE, as well as in neuron and astrocyte cell bodies. ProBDNF and p75(NTR) increased independently of cell death and their localization was different depending on the severity of SE. We also examined the expression of proneurotrophin co-receptors, sortilin and sorCS2. Following severe SE, sorCS2, but not sortilin, was elevated in neurons and astrocytes. These data indicate that important differences exist between rat and mouse in the proneurotrophin response following SE. Moreover, the proBDNF and p75(NTR) increase after seizures in the absence of significant cell death suggests that proneurotrophin signaling may play other roles following SE. PMID:25290065

  7. Erythrocyte peripheral type benzodiazepine receptor/voltage-dependent anion channels are upregulated by Plasmodium falciparum.

    PubMed

    Bouyer, Guillaume; Cueff, Anne; Egée, Stéphane; Kmiecik, Justyna; Maksimova, Yelena; Glogowska, Edyta; Gallagher, Patrick G; Thomas, Serge L Y

    2011-08-25

    Plasmodium falciparum relies on anion channels activated in the erythrocyte membrane to ensure the transport of nutrients and waste products necessary for its replication and survival after invasion. The molecular identity of these anion channels, termed "new permeability pathways" is unknown, but their currents correspond to up-regulation of endogenous channels displaying complex gating and kinetics similar to those of ligand-gated channels. This report demonstrates that a peripheral-type benzodiazepine receptor, including the voltage dependent anion channel, is present in the human erythrocyte membrane. This receptor mediates the maxi-anion currents previously described in the erythrocyte membrane. Ligands that block this peripheral-type benzodiazepine receptor reduce membrane transport and conductance in P falciparum-infected erythrocytes. These ligands also inhibit in vitro intraerythrocytic growth of P falciparum. These data support the hypothesis that dormant peripheral-type benzodiazepine receptors become the "new permeability pathways" in infected erythrocytes after up-regulation by P falciparum. These channels are obvious targets for selective inhibition in anti-malarial therapies, as well as potential routes for drug delivery in pharmacologic applications. PMID:21795748

  8. Naringenin confers protection against oxidative stress through upregulation of Nrf2 target genes in cardiomyoblast cells.

    PubMed

    Ramprasath, Tharmarajan; Senthamizharasi, Manivasagam; Vasudevan, Varadaraj; Sasikumar, Sundaresan; Yuvaraj, Subramani; Selvam, Govindan Sadasivam

    2014-06-01

    Cardiovascular diseases are the major health concern and the leading cause of death. Numerous studies have shown that oxidative stress stimuli have been incriminated in the pathogenesis of both acute and chronic heart disease. Though it is well known that bioflavonoids protect cells against reactive oxygen species (ROS)-induced damage, the molecular mechanisms involved are uncertain. Understanding the possible intracellular signaling pathways triggered by flavonoids will help to overcome the cardiac diseases resulting from oxidative stress. In the present study, we investigated whether naringenin (NGN) supplementation would improve the antioxidant defence under oxidative stress through the activation of Nrf2 signaling in cultured cardiomyoblast. NGN pretreatment significantly reduced stress-mediated apoptotic cell death and lipid peroxidation and showed increased level of reduced glutathione in H2O2-treated cardiomyoblast. In addition, NGN inhibited the production of NO and trigged the synthesis of antioxidant marker enzymes. Gene expression studies revealed that NGN upregulated the transcription of Akt and downregulated NF-?B and Caspase 3 genes. Notably, transcription of Nrf2 and its target genes was also upregulated. Taken together, the present study revealed that NGN elicits potent cytoprotective effect against oxidative stress by regulating Nrf2 and its target genes. In conclusion, the present work suggests that improving Nrf2 signaling by NGN supplementation would be a rational approach to facilitate ROS detoxification by augmenting both expression and activity of phase II detoxification enzymes for the alleviation of cardiac complications. PMID:24526395

  9. Temperature-dependent sex determination: upregulation of SOX9 expression after commitment to male development.

    PubMed

    Western, P S; Harry, J L; Graves, J A; Sinclair, A H

    1999-03-01

    In mammals, birds and reptiles the morphological development of the gonads appear to be conserved. This conservation is evident despite the different sex determining switches employed by these vertebrate groups. Mammals exhibit chromosomal sex determination (CSD) where the key sex determining switch is the Y-linked gene, SRY. Although SRY is the trigger for testis determination in mammals, it is not conserved in other vertebrate groups. However, a gene closely related to SRY, the highly conserved transcription factor, SOX9, plays an important role in the testis pathway of mammals and birds. In contrast to the CSD mechanism evident in mammals and birds, many reptiles exhibit temperature dependent sex determination (TSD) where the egg incubation temperature triggers sex determination. Here we examine the expression of SOX9 during gonadogenesis in the American alligator, (Alligator mississippiensis), a reptile that exhibits TSD. Alligator SOX9 is expressed in the embryonic testis but not in the ovary. However, the timing of SOX9 upregulation in the developing testis is not consistent with a role for this gene in the early stages of alligator sex determination. Since SOX9 upregulation in male embryos coincides with the structural organisation of the testis, SOX9 may operate farther downstream in the vertebrate sex differentiation pathway than previously postulated. PMID:10090144

  10. Cisplatin induces apoptosis via upregulating Wrap53 in U-2OS osteosarcoma cells.

    PubMed

    Yuan, Jian-Min; Li, Xue-Dong; Liu, Zhao-Yong; Hou, Guo-Qing; Kang, Jian-Hui; Huang, Dong-Yang; Du, Shi-Xin

    2011-01-01

    Wrap531?, a newly identified natural antisense transcript of p53, can regulate p53 expression upon DNA damage. We sought to investigate changes in Wrap53 and p53 levels in an osteosarcoma cell line (U-2OS) exposed to cisplatin and to study apoptosis before and after knockdown of Wrap53. Our RT-PCR analysis showed a dose- dependent 3 to 40-fold increase in Wrap53 mRNA transcript levels in U-2OS exposed to 5 to 20 ?M cisplatin. An approximate 2-fold increase was also observed in transcript levels of p53 mRNA. Furthermore, transient knockdown of Wrap53 by siRNAs in U-2OS cells treated with 10 ?M cisplatin reduced p53 mRNA transcript levels by up to 50% of those of controls. Immunoblotting analysis showed that in U-2OS cells treated with siRNA against exon 4 of the Wrap53 gene, the protein level of p53 was also markedly reduced. Our findings suggest that cisplatin upregulates the expression of p53 in osteosarcoma cells by upregulating the transcript levels of Wrap53. Finally, measurement of apoptotic cell death by flow cytometry showed that knockdown of Wrap53 reduced apotosis in U-2OS cells induced by cisplatin. PMID:22471498

  11. 17?-estradiol upregulates GREB1 and accelerates ovarian tumor progression in vivo

    PubMed Central

    Laviolette, Laura A; Hodgkinson, Kendra M; Minhas, Neha; Perez-Iratxeta, Carol; Vanderhyden, Barbara C

    2014-01-01

    Exogenous 17?-estradiol (E2) accelerates the progression of ovarian cancer in the transgenic tgCAG-LS-TAg mouse model of the disease. We hypothesized that E2 has direct effects on ovarian cancer cells and this study was designed to determine the molecular mechanisms by which E2 accelerates ovarian tumor progression. Mouse ovarian cancer ascites (MAS) cell lines were derived from tgCAG-LS-TAg mice. Following intraperitoneal engraftment of two MAS cell lines, MASC1 and MASE2, into SCID mice, exogenous E2 significantly decreased the survival time and increased the tumor burden. Microarray analysis performed on MASE2-derived tumors treated with E2 or placebo showed that E2 treatment caused the upregulation of 197 genes and the downregulation of 55 genes. The expression of gene regulated by estrogen in breast cancer 1 (Greb1) was upregulated in mouse tumors treated with E2 and was overexpressed in human ovarian cancers relative to human ovarian surface epithelium, suggesting a role for GREB1 in human ovarian tumor progression. RNA interference-mediated knockdown of GREB1 in MASE2 cells decreased their proliferation rate in vitro and increased survival time in mice engrafted with the cells. These results emphasize the importance of E2 in ovarian tumor progression and identify Greb1 as a novel gene target for therapeutic intervention. PMID:24469735

  12. Amphiregulin activates human hepatic stellate cells and is upregulated in non alcoholic steatohepatitis

    PubMed Central

    McKee, Chad; Sigala, Barbara; Soeda, Junpei; Mouralidarane, Angelina; Morgan, Maelle; Mazzoccoli, Gianluigi; Rappa, Francesca; Cappello, Francesco; Cabibi, Daniela; Pazienza, Valerio; Selden, Claire; Roskams, Tania; Vinciguerra, Manlio; Oben, Jude A.

    2015-01-01

    Amphiregulin (AR) involvement in liver fibrogenesis and hepatic stellate cells (HSC) regulation is under study. Non-alcoholic fatty liver disease (NAFLD) and its more severe form non-alcoholic steatohepatitis (NASH) may progress to cirrhosis and hepatocellular cancer (HCC). Our aim was to investigate ex vivo the effect of AR on human primary HSC (hHSC) and verify in vivo the relevance of AR in NAFLD fibrogenesis. hHSC isolated from healthy liver segments were analyzed for expression of AR and its activator, TNF-? converting enzyme (TACE). AR induction of hHSC proliferation and matrix production was estimated in the presence of antagonists. AR involvement in fibrogenesis was also assessed in a mouse model of NASH and in humans with NASH. hHSC time dependently expressed AR and TACE. AR increased hHSC proliferation through several mitogenic signaling pathways such as EGFR, PI3K and p38. AR also induced marked upregulation of hHSC fibrogenic markers and reduced hHSC death. AR expression was enhanced in the HSC of a murine model of NASH and of severe human NASH. In conclusion, AR induces hHSC fibrogenic activity via multiple mitogenic signaling pathways, and is upregulated in murine and human NASH, suggesting that AR antagonists may be clinically useful anti-fibrotics in NAFLD. PMID:25744849

  13. Sepsis and glucocorticoids upregulate p300 and downregulate HDAC6 expression and activity in skeletal muscle

    PubMed Central

    Alamdari, Nima; Smith, Ira J.; Aversa, Zaira

    2010-01-01

    Muscle wasting during sepsis is in part regulated by glucocorticoids. In recent studies, treatment of cultured muscle cells in vitro with dexamethasone upregulated expression and activity of p300, a histone acetyl transferase (HAT), and reduced expression and activity of the histone deacetylases-3 (HDAC3) and -6, changes that favor hyperacetylation. Here, we tested the hypothesis that sepsis and glucocorticoids regulate p300 and HDAC3 and -6 in skeletal muscle in vivo. Because sepsis-induced metabolic changes are particularly pronounced in white, fast-twitch skeletal muscle, most experiments were performed in extensor digitorum longus muscles. Sepsis in rats upregulated p300 mRNA and protein levels, stimulated HAT activity, and reduced HDAC6 expression and HDAC activity. The sepsis-induced changes in p300 and HDAC expression were prevented by the glucocorticoid receptor antagonist RU38486. Treatment of rats with dexamethasone increased expression of p300 and HAT activity, reduced expression of HDAC3 and -6, and inhibited HDAC activity. Finally, treatment with the HDAC inhibitor trichostatin A resulted in increased muscle proteolysis and expression of the ubiquitin ligase atrogin-1. Taken together, our results suggest for the first time that sepsis-induced muscle wasting may be regulated by glucocorticoid-dependent hyperacetylation caused by increased p300 and reduced HDAC expression and activity. The recent development of pharmacological HDAC activators may provide a novel avenue to prevent and treat muscle wasting in sepsis and other catabolic conditions. PMID:20538901

  14. TRPV1 activation improves exercise endurance and energy metabolism through PGC-1? upregulation in mice

    PubMed Central

    Luo, Zhidan; Ma, Liqun; Zhao, Zhigang; He, Hongbo; Yang, Dachun; Feng, Xiaoli; Ma, Shuangtao; Chen, Xiaoping; Zhu, Tianqi; Cao, Tingbing; Liu, Daoyan; Nilius, Bernd; Huang, Yu; Yan, Zhencheng; Zhu, Zhiming

    2012-01-01

    Impaired aerobic exercise capacity and skeletal muscle dysfunction are associated with cardiometabolic diseases. Acute administration of capsaicin enhances exercise endurance in rodents, but the long-term effect of dietary capsaicin is unknown. The capsaicin receptor, the transient receptor potential vanilloid 1 (TRPV1) cation channel has been detected in skeletal muscle, the role of which remains unclear. Here we report the function of TRPV1 in cultured C2C12 myocytes and the effect of TRPV1 activation by dietary capsaicin on energy metabolism and exercise endurance of skeletal muscles in mice. In vitro, capsaicin increased cytosolic free calcium and peroxisome proliferator-activated receptor-? coactivator-1? (PGC-1?) expression in C2C12 myotubes through activating TRPV1. In vivo, PGC-1? in skeletal muscle was upregulated by capsaicin-induced TRPV1 activation or genetic overexpression of TRPV1 in mice. TRPV1 activation increased the expression of genes involved in fatty acid oxidation and mitochondrial respiration, promoted mitochondrial biogenesis, increased oxidative fibers, enhanced exercise endurance and prevented high-fat diet-induced metabolic disorders. Importantly, these effects of capsaicin were absent in TRPV1-deficient mice. We conclude that TRPV1 activation by dietary capsaicin improves energy metabolism and exercise endurance by upregulating PGC-1? in skeletal muscles. The present results indicate a novel therapeutic strategy for managing metabolic diseases and improving exercise endurance. PMID:22184011

  15. Regulatory T cells contribute to the recovery of acute lung injury by upregulating tim-3.

    PubMed

    Song, Haihan; Zhou, Yujia; Li, Guanggang; Bai, Jianwen

    2015-06-01

    Acute lung injury (ALI) is characterized by alveolar injury and uncontrolled inflammation. Mechanisms underlying pathogenesis of ALI are unknown. Regulatory T cells (Tregs), either natural or induced, suppress a variety of physiological and pathological immune responses. In the current study, we investigated whether Tregs were involved in the development of ALI. Proportion of CD4 + CD25 + FoxP3+ Tregs in the peripheral blood of 66 ALI patients and 30 healthy controls were examined by flow cytometry. Data showed that the percentage of Tregs in CD4+ T cells was significantly increased in patients than that in controls (10.8 versus 7.6 %, P?=?0.003). Also, compared to those who died during the study, patients who survived presented significantly higher level of Tregs at the time of recruitment (P?=?0.041). Since Tim-3 is a negative regulatory molecule and can modulate the function of Tregs, we evaluated Tim-3 level on Tregs and identified upregulation of the molecule in patients than that in controls. Moreover, compared to those who died during the study, patients who survived showed 1.7-fold higher level of Tim-3 on Tregs at the time of recruitment (P?upregulation of Tim-3. PMID:25526715

  16. Fas Signaling Promotes Gastric Cancer Metastasis through STAT3-Dependent Upregulation of Fascin

    PubMed Central

    Cai, Zhijian; Cheng, Guoping; Chen, Ming; Wang, Jiaoli; Zhong, Haijun

    2015-01-01

    Background Fas signaling-activated signal transducers and activators of transcription 3 (STAT3) is required for Fascin upregulation. As an actin-bundling protein, Fascin can mediate gastric cancer (GC) cell migration. Methods Gastric cancer AGS cells were treated with anti-Fas (5 ?g/ml) for 2 h, in order to stimulate the activation of the Fas signaling. The in vitro migration of Fas signaling-activated AGS cells was assessed using Transwell chambers. The levels of Fascin and phosphorylated STAT3 were detected by Western blotting analyses. Nude mice were injected intravenously with AGS cells treated with anti-Fas or treated with STAT3 inhibitor without anti-Fas; tumor pulmonary metastases were measured. Fascin protein expression in tumor tissues was detected by immunohistochemistry. The Fas and Fascin mRNA levels in tumor tissues from patients with GC were measured by real-time PCR and their correlation was analyzed. Results The activation of Fas signaling promoted cell migration and resulted in STAT3-dependent Fascin upregulation in AGS cells. STAT3 enhanced Fascin levels in vivo. Fascin was the mediator of Fas signaling-induced AGS cell migration in vitro and in vivo. Furthermore, there was a positive correlation between Fas and Fascin mRNA levels in tumor tissues from GC patients. Conclusions Fas signaling promotes GC metastasis through the STAT3/Fascin pathway, which may provide a new target for GC therapy. PMID:25992623

  17. Upregulation of GRIM?19 inhibits the growth and invasion of human breast cancer cells.

    PubMed

    Zhang, Wei; Du, Ye; Jiang, Tong; Geng, Wei; Yuan, Jiuli; Zhang, Duo

    2015-08-01

    Gene associated with retinoid?interferon (IFN)?induced mortality 19 (GRIM?19), a novel IFN??/retinoic acid?inducible gene product, has been identified as a potential tumor suppressor, which is associated with the inhibition of tumor growth. GRIM?19 has been demonstrated to be downregulated in the ovarian tissue of patients with breast cancer, however, its role in breast cancer remains to be fully elucidated. In the present study, a recombinant eukaryotic expression plasmid carrying GRIM?19 was constructed and then transfected into the MCF7 human breast cancer cell line to examine its effects on breast cancer cell growth, migration and invasion using several in vitro approaches. The results demonstrated that upregulation GRIM?19 in the MCF7 cells significantly inhibited cell proliferation, colony formation, migration and invasion, and induced cell apoptosis. Additionally, upregulation of GRIM?19 also suppressed the secretion of urokinase?type plasminogen activator (u?PA), matrix metalloproteinase (MMP)?2, MMP?9 and vascular endothelial growth factor (VEGF). It was also demonstrated that the activation of signal transducer and activator of transcription 3 (STAT3) was downregulated by the expression of GRIM?19. These results revealed that overexpression of the GRIM?19 gene may be an effective approach to control the growth and invasion of human breast cancer cells. PMID:25955394

  18. PPAR? inhibits ovarian cancer cells proliferation through upregulation of miR-125b.

    PubMed

    Luo, Shuang; Wang, Jidong; Ma, Ying; Yao, Zhenwei; Pan, Hongjuan

    2015-06-26

    miR-125b has essential roles in coordinating tumor proliferation, angiogenesis, invasiveness, metastasis and chemotherapy recurrence. In ovarian cancer miR-125b has been shown to be downregulated and acts as a tumor suppressor by targeting proto-oncogene BCL3. PPAR?, a multiple functional transcription factor, has been reported to have anti-tumor effects through inhibition of proliferation and induction of differentiation and apoptosis by targeting the tumor related genes. However, it is unclear whether miR-125b is regulated by PPAR? in ovarian cancer. In this study, we demonstrated that the miR-125b downregulated in ovarian cancer tissues and cell lines. Ligands-activated PPAR? suppressed proliferation of ovarian cancer cells and this PPAR?-induced growth inhibition is mediated by the upregulation of miR-125b. PPAR? promoted the expression of miR-125b by directly binding to the responsive element in miR-125b gene promoter region. Thus, our results suggest that PPAR? can induce growth suppression of ovarian cancer by upregulating miR-125b which inhibition of proto-oncogene BCL3. These findings will extend our understanding of the function of PPAR? in tumorigenesis and miR-125b may be a therapeutic intervention of ovarian cancer. PMID:25944662

  19. Upregulated microRNA-16 as an oncogene in renal cell carcinoma.

    PubMed

    Chen, Duqun; Li, Yifan; Yu, Zuhu; Su, Zhengming; Yu, Wenshui; Li, Yuchi; Yang, Shangqi; Gui, Yaoting; Ni, Liangchao; Lai, Yongqing

    2015-07-01

    MicroRNAs (miRs) are small, endogenous noncoding RNAs that serve a significant function in various biologic processes, including those involved in cancer. The present study aimed to determine the expression and function of miR-16 in renal cell carcinoma (RCC). Quantitative polymerase chain reaction was used to quantify the expression of miR-16 in 48 paired RCC tissues and adjacent normal tissues. The impact of miR-16 on cell proliferation, migration and apoptosis was analyzed by transfecting miR-16 mature molecules into the renal cancer cell lines 786-O and ACHN. The results indicated that miR-16 was significantly upregulated in RCC tissues (P<0.05). Downregulation of miR-16 resulted in reduced cell proliferation and migration and increased levels of apoptosis, while overexpression of miR-16 resulted in accelerated cellular proliferation and migration, suggesting that miR-16 may function as an oncogene in RCC. The present study demonstrated for the first time, to the best of our knowledge, that miR-16 is upregulated in RCC and acts as an oncogene by inducing cellular proliferation, migration and reducing apoptosis. Further study of miR-16 in RCC may clarify the molecular mechanisms of RCC carcinogenesis and aid in the development of novel biomarkers and therapeutic options. PMID:25815587

  20. Molecular cloning and functional characterization of a mouse gene upregulated by lipopolysaccharide treatment reveals alternative splicing

    SciTech Connect

    Du, Kejun; Chen, Yaoming; Dai, Zongming; Bi, Yuan; Cai, Tongjian [Department of Occupational and Environmental Health, Fourth Military Medical University, Xi'an 710032, Shaanxi Province (China)] [Department of Occupational and Environmental Health, Fourth Military Medical University, Xi'an 710032, Shaanxi Province (China); Hou, Lichao [Department of Anesthesiology, Xijing Hospital, Fourth Military Medical University, Xi'an 710032, Shaanxi Province (China)] [Department of Anesthesiology, Xijing Hospital, Fourth Military Medical University, Xi'an 710032, Shaanxi Province (China); Chai, Yubo; Song, Qinghe; Chen, Sumin [Department of Biochemistry and Molecular Biology, Fourth Military Medical University, Xi'an 710032, Shaanxi Province (China)] [Department of Biochemistry and Molecular Biology, Fourth Military Medical University, Xi'an 710032, Shaanxi Province (China); Luo, Wenjing, E-mail: luowenj@fmmu.edu.cn [Department of Occupational and Environmental Health, Fourth Military Medical University, Xi'an 710032, Shaanxi Province (China)] [Department of Occupational and Environmental Health, Fourth Military Medical University, Xi'an 710032, Shaanxi Province (China); Chen, Jingyuan, E-mail: jy_chen@fmmu.edu.cn [Department of Occupational and Environmental Health, Fourth Military Medical University, Xi'an 710032, Shaanxi Province (China)] [Department of Occupational and Environmental Health, Fourth Military Medical University, Xi'an 710032, Shaanxi Province (China)

    2010-01-01

    Treatment of mouse cells with lipopolysaccharide (LPS) potently initiates an inflammatory response, but the underlying mechanisms are unclear. We therefore sought to characterize cDNA sequences of a new mouse LPS-responsive gene, and to evaluate the effects of MLrg. Full-length cDNAs were obtained from LPS-treated NIH3T3 cells. We report that the MLrg gene produces two alternative splice products (GenBank Accession Nos. (DQ316984) and (DQ320011)), respectively, encoding MLrgW and MLrgS polypeptides. Both proteins contain zinc finger and leucine zipper domains and are thus potential regulators of transcription. Expression of MLrgW and MLrgS were robustly upregulated following LPS treatment, and the proteins were localized predominantly in the nuclear membrane and cytoplasm. In stable transfectants over-expressing MLrgW the proportion of cells in G1 phase was significantly reduced, while in cells over-expressing MLrgS the proportion of cells in G2 was significantly increased; both proteins are thus potential regulators of cell cycle progression. Upregulation of MLrgW and MLrgS may be an important component of the LPS inflammatory pathway and of the host response to infection with GNB.

  1. Up-regulation of NF45 correlates with Schwann cell proliferation after sciatic nerve crush.

    PubMed

    Wang, Youhua; Zhou, Shiran; Xu, Hua; Yan, Shixian; Xu, Dawei; Zhang, Yi

    2015-05-01

    Nuclear factor (NF)45 (also known as interleukin enhancer-binding factor (ILF)2), is a transcription factor that interacts with NF90 to regulate gene expression. It has long been implicated in the regulation of cell proliferation. However, the role of NF45 in the process of peripheral nervous system regeneration after injury remains poorly understood. Herein, we investigated the spatiotemporal expression of NF45 in a rat sciatic nerve crush model. We detected the up-regulated expression of NF45 in Schwann cell after sciatic nerve crush. What's more, the expression of the cell proliferation marker proliferating cell nuclear antigen (PCNA) exhibited a similar tendency with that of NF45. In cell cultures, we observed increased expression of NF45 during the process of TNF-?-induced Schwann cell proliferation, whereas the protein level of p21 was down-regulated. Interference of NF45 led to enhanced expression of p21 and also impaired proliferation of Schwan cells. Taken together, our data implicated that NF45 was up-regulated in the sciatic nerve after crush, which was associated with proliferation of Schwann cell. PMID:25566957

  2. Irinotecan resistance is accompanied by upregulation of EGFR and Src signaling in human cancer models.

    PubMed

    Petitprez, Amelie; Larsen, Annette K

    2013-01-01

    Irinotecan is a major drug for treatment of metastatic colorectal cancer and a promising agent for other applications like gastric cancer. Its clinical activity is currently limited by both intrinsic (natural) and acquired drug resistance. A better understanding of the underlying resistance mechanisms is needed to develop novel therapeutic strategies. Exposure of tumor cells to irinotecan or its active metabolite SN-38 is accompanied by EGFR activation, either by stimulation of EGFR autophosphorylation or by Src-mediated phosphorylation. Accordingly, combinations of irinotecan and EGFR inhibitors have been associated with supra-additive activity. We now show that acquired resistance to SN-38 is accompanied by increased expression of EGFR, HER2, HER3 and Src proteins in two colorectal cancer cell models as well as by Src activation. One SN-38 resistant model (HT-29) showed increased sensitivity to erlotinib, an EGFR inhibitor, and afatinib, a dual EGFR/HER2 inhibitor, while the other SN-38 resistant model (HCT-116) showed increased resistance to erlotinib but unchanged or increased sensitivity to afatinib. Unexpectedly, both models showed increased or unaltered resistance to the Src inhibitor dasatinib. Therefore, tyrosine kinase upregulation is not necessarily accompanied by increased sensitivity to targeted agents. Taken together, our findings demonstrate that prolonged exposure to topoisomerase I inhibitors is accompanied by upregulation of different signal transduction pathways which can alter tumor sensitivity to molecular targeted agents. These results suggest that chemotherapy exposure may lead to creation of novel targets which could be exploited therapeutically. PMID:22973964

  3. Up-regulation of glycolytic metabolism is required for HIF1?-driven bone formation

    PubMed Central

    Regan, Jenna N.; Lim, Joohyun; Shi, Yu; Joeng, Kyu Sang; Arbeit, Jeffrey M.; Shohet, Ralph V.; Long, Fanxin

    2014-01-01

    The bone marrow environment is among the most hypoxic in the body, but how hypoxia affects bone formation is not known. Because low oxygen tension stabilizes hypoxia-inducible factor alpha (HIF?) proteins, we have investigated the effect of expressing a stabilized form of HIF1? in osteoblast precursors. Brief stabilization of HIF1? in SP7-positive cells in postnatal mice dramatically stimulated cancellous bone formation via marked expansion of the osteoblast population. Remarkably, concomitant deletion of vascular endothelial growth factor A (VEGFA) in the mouse did not diminish bone accrual caused by HIF1? stabilization. Thus, HIF1?-driven bone formation is independent of VEGFA up-regulation and increased angiogenesis. On the other hand, HIF1? stabilization stimulated glycolysis in bone through up-regulation of key glycolytic enzymes including pyruvate dehydrogenase kinase 1 (PDK1). Pharmacological inhibition of PDK1 completely reversed HIF1?-driven bone formation in vivo. Thus, HIF1? stimulates osteoblast formation through direct activation of glycolysis, and alterations in cellular metabolism may be a broadly applicable mechanism for regulating cell differentiation. PMID:24912186

  4. Streptococcus pneumoniae synergizes with nontypeable Haemophilus influenzae to induce inflammation via upregulating TLR2

    PubMed Central

    Lim, Jae Hyang; Ha, Unhwan; Sakai, Akihiro; Woo, Chang-Hoon; Kweon, Soo-Mi; Xu, Haidong; Li, Jian-Dong

    2008-01-01

    Background Toll-like receptor 2 (TLR2) plays a critical role in mediating inflammatory/immune responses against bacterial pathogens in lung. Streptococcus pneumoniae (S. pneumoniae) and nontypeable Haemophilus influenzae (NTHi) were previously reported to synergize with each other to induce inflammatory responses. Despite the relatively known intracellular signaling pathways involved in the synergistic induction of inflammation, it is still unclear if both bacterial pathogens also synergistically induce expression of surface TLR2. Results Here we provide direct evidence that S. pneumoniae synergizes with NTHi to upregulate TLR2 expression in lung and middle ear of the mice. Pneumolysin (PLY) appears to be the major virulence factor involved in this synergism. Moreover, S. pneumoniae PLY induces TLR2 expression via a TLR4-MyD88-NF-?B-dependent signaling pathway. Interestingly, tumor suppressor CYLD acts as a negative regulator of S. pneumoniae-induced TLR2 up-regulation via negative-crosstalk with NF-?B signaling. Conclusion Our study thus provides novel insights into the regulation of TLR2 expression in mixed bacterial infections. PMID:18664270

  5. KRIT1 loss of function causes a ROS-dependent upregulation of c-Jun

    PubMed Central

    Goitre, Luca; De Luca, Elisa; Braggion, Stefano; Trapani, Eliana; Guglielmotto, Michela; Biasi, Fiorella; Forni, Marco; Moglia, Andrea; Trabalzini, Lorenza; Retta, Saverio Francesco

    2014-01-01

    Loss-of-function mutations in the KRIT1 gene (CCM1) have been associated with the pathogenesis of cerebral cavernous malformations (CCM), a major cerebrovascular disease. However, KRIT1 functions and CCM pathogenetic mechanisms remain incompletely understood. Indeed, recent experiments in animal models have clearly demonstrated that the homozygous loss of KRIT1 is not sufficient to induce CCM lesions, suggesting that additional factors are necessary to cause CCM disease. Previously, we found that KRIT1 is involved in the maintenance of the intracellular reactive oxygen species (ROS) homeostasis to prevent ROS-induced cellular dysfunctions, including a reduced ability to maintain a quiescent state. Here, we show that KRIT1 loss of function leads to enhanced expression and phosphorylation of the redox-sensitive transcription factor c-Jun, as well as induction of its downstream target COX-2, in both cellular models and human CCM tissues. Furthermore, we demonstrate that c-Jun upregulation can be reversed by either KRIT1 re-expression or ROS scavenging, whereas KRIT1 overexpression prevents forced upregulation of c-Jun induced by oxidative stimuli. Taken together with the reported role of c-Jun in vascular dysfunctions triggered by oxidative stress, our findings shed new light on the molecular mechanisms underlying KRIT1 function and CCM pathogenesis. PMID:24291398

  6. Hepatitis B virus upregulates the expression of kinesin family member 4A.

    PubMed

    Zhu, Cheng-Liang; Cheng, Duo-Zhi; Liu, Fang; Yan, Xiao-Hong; Wu, Kai-Lang; Wang, Fu-Bing; Liu, Xing-Hui

    2015-09-01

    Hepatitis B virus (HBV) infection is one of the major causes of hepatocellular carcinoma (HCC). Kinesin family member 4A (KIF4A) is a microtubule?based motor protein, which is upregulated in cervical and lung cancer. However, the expression of KIF4A in HBV?associated HCC, and the effect of HBV on the expression of KIF4A remain to be elucidated. In the present study, the expression profiles of KIF4A were examined in cancerous tissues and paracancerous tissues from patients with HCC, who presented with histories of chronic HBV infection, and the role of HBV in the induction of the expression of KIF4A was investigated. HepG2 cells were transfected with the pHBV1.3, HBV infectious clone and a construct, which contained the luciferase gene under the control of the KIF4A gene promoter. The results demonstrated that the expression of KIF4A was significantly higher in the HCC tissues than in the paracancerous tissues. HBV activated the KIF4A gene promoter and upregulated the mRNA and protein expression of KIF4A. Furthermore, activation of the gene expression of KIF4A increased in a pHBV1.3 concentration?dependent manner. These results provide novel insights into the understanding of HCC oncogenesis caused by HBV. PMID:25998931

  7. RAD001 (everolimus) enhances TRAIL cytotoxicity in human leukemic Jurkat T cells by upregulating DR5.

    PubMed

    Lee, Myoung Woo; Kim, Dae Seong; Eom, Ji-Eun; Ko, Young Jong; Sung, Ki Woong; Koo, Hong Hoe; Yoo, Keon Hee

    2015-08-01

    Tumor necrosis factor-related apoptosis-inducing ligand (TRAIL), either alone or in combination with other anti-cancer agents, is a promising new strategy for the treatment of cancer. However, aberrant PI3K/Akt/mTOR survival signaling may confer TRAIL resistance by altering the balance between pro- and anti-apoptotic proteins. In the present study, we showed that the Akt/mTOR inhibitor RAD001 (everolimus) induced cell death in a dose-dependent manner and enhanced TRAIL-induced apoptosis in human leukemic Jurkat T cells, which show PI3K/Akt/mTOR pathway activation and basal expression levels of death receptor (DR) 5 (TRAIL-R2). Investigation of the effect of RAD001 treatment on the expression of TRAIL receptors (TRAIL-Rs) in Jurkat T cells showed that RAD001 significantly upregulated DR5 by up to 51.22%, but not other TRAIL-Rs such as DR4 (TRAIL-R1), decoy receptor (DcR) 1 (TRAIL-R3), and DcR2 (TRAIL-R4). Pretreatment with DR5:Fc chimera abrogated the RAD001-induced increase of TRAIL cytotoxicity, indicating that the upregulation of DR5 by RAD001 plays a role in enhancing the susceptibility of Jurkat T cells to TRAIL. Our results indicate that combination treatment with RAD001 and TRAIL may be a novel therapeutic strategy in leukemia. PMID:26074143

  8. Upregulated UHRF1 Promotes Bladder Cancer Cell Invasion by Epigenetic Silencing of KiSS1

    PubMed Central

    Zhu, Zhiqiang; Zheng, Xin; Liu, Jianwei; Han, Zhiyou; Ma, Xuetao; Zhang, Yuhai

    2014-01-01

    Ubiquitin-like with PHD and RING finger domains 1 (UHRF1), as an epigenetic regulator, plays important roles in the tumorigenesis and cancer progression. KiSS1 functions as a metastasis suppressor in various cancers, and epigenetic silencing of KiSS1 increases the metastatic potential of cancer cells. We therefore investigated whether UHRF1 promotes bladder cancer cell invasion by inhibiting KiSS1. The expression levels of UHRF1 and KiSS1 were examined by quantitative real-time PCR assay in vitro and in vivo. The role of UHRF1 in regulating bladder cancer metastasis was evaluated in bladder cancer cell. We found that UHRF1 levels are upregulated in most clinical specimens of bladder cancer when compared with paired normal tissues, and UHRF1 expression levels are significantly increased in primary tumors that subsequently metastasized compared with non-metastatic tumors. Forced expression of UHRF1 promotes bladder cancer cell invasion, whereas UHRF1 knockdown decreases cell invasion. Overexpression of UHRF1 increases the methylation of CpG nucleotides and reduces the expression of KiSS1. UHRF1 and KiSS1 expression level is negatively correlated in vivo and in vitro. Knockdown of KiSS1 promotes bladder cancer cell invasion. Importantly, forced expression of KiSS1 partly abrogates UHRF1-induced cell invasion. These data demonstrated that upregulated UHRF1 increases bladder cancer cell invasion by epigenetic silencing of KiSS1. PMID:25272010

  9. Ulinastatin reduces urinary sepsis?related inflammation by upregulating IL?10 and downregulating TNF?? levels.

    PubMed

    Chen, Xian; Wang, Yi; Luo, Hongmei; Luo, Zhigang; Liu, Lisha; Xu, Wujun; Zhang, Tao; Yang, Ning; Long, Xiangyang; Zhu, Neng; Xie, Huang; Liu, Jun

    2013-07-01

    The aim of the present study was to determine the efficacy of ulinastatin (UTI) for the treatment of sepsis and to investigate the associated molecular mechanisms. Twenty?four male rabbits were randomly divided into 4 groups, the normal, sham, sepsis model and UTI groups, each containing 6 rabbits. Serum levels of interleukin (IL)?10 and tumor necrosis factor?? (TNF??) were measured by enzyme?linked immunosorbent assay (ELISA). Liver, kidney and lung tissues were stained with hematoxylin and eosin (H&E) 36 h after sacrifice and morphological changes were observed under an optical microscope. The expression levels of IL?10 and TNF?? proteins in rabbit kidney tissue in each group were determined by immunohistochemical detection and western blot analysis. ELISA results indicated that, compared with the sepsis model, IL?10 levels were significantly higher in the UTI treatment group (183.91±11.521 pg/ml) at 36 h (P=0.000), while serum TNF?? concentration decreased significantly in the UTI treatment group (31.637±2.770 pg/ml; P=0.000). Results of western blot analysis were consistent with the immunohistochemistry, indicating that UTI upregulates IL?10 and downregulates TNF?? levels. In the current study, UTI was demonstrated to effectively treat urinary sepsis and alleviate the inflammatory response in tissues. These effects were mediated by the upregulation of IL?10 and downregulation of TNF?? levels. PMID:23685622

  10. Twist1 Promotes Gastric Cancer Cell Proliferation through Up-Regulation of FoxM1

    PubMed Central

    Gu, Xiaoqiang; Zhan, Wang; Wang, Xi

    2013-01-01

    Twist-related protein 1 (Twist1), also known as class A basic helix-loop-helix protein 38 (bHLHa38), has been implicated in cell lineage determination and differentiation. Previous studies demonstrate that Twist1 expression is up-regulated in gastric cancer with poor clinical outcomes. Besides, Twist1 is suggested to be involved in progression of human gastric cancer. However, its biological functions remain largely unexplored. In the present study, we show that Twist 1 overexpression leads to a significant up-regulation of FoxM1, which plays a key role in cell cycle progression in gastric cancer cells. In contrast, knockdown of Twist 1 reduces FoxM1 expression, suggesting that FoxM1 might be a direct transcriptional target of Twist 1. At the molecular level, we further reveal that Twist 1 could bind to the promoter region of FoxM1, and subsequently recruit p300 to induce FoxM1 mRNA transcription. Therefore, our results uncover a previous unknown Twist 1/FoxM1 regulatory pathway, which may help to understand the mechanisms of gastric cancer proliferation. PMID:24204899

  11. Lipoteichoic acid upregulates NF-?B and proinflammatory cytokines by modulating ?-catenin in bronchial epithelial cells.

    PubMed

    Jang, Jaewoong; Kim, Wonyong; Kim, Kijeong; Chung, Sang-In; Shim, Yae Jie; Kim, Seok-Min; Yoon, Yoosik

    2015-09-01

    Lipoteichoic acid (LTA) is a major cell wall component and virulence factor of gram-positive bacteria. The present study investigated the LTA?induced inflammatory response of BEAS?2B human bronchial epithelial cells, and detected the expression levels of proinflammatory cytokines interleukin (IL)?6, IL?8, IL?1?, tumour necrosis factor?? and monocyte chemotactic protein?1, the upregulation of NF??B, and the phosphorylation and degradation of I??B. During the LTA?induced inflammatory response of the BEAS?2B human bronchial epithelial cells, the activity levels of the ??catenin?dependent promoter, and the protein expression levels of ??catenin were significantly upregulated, whereas ??catenin phosphorylation and the expression levels of AXIN were significantly downregulated. Following knockdown of ??catenin by small interfering (si)RNA transfection, both the LTA-induced protein expression levels of NF??B and the LTA-induced activity levels of the NF??B?dependent promoter were significantly reduced. Similarly, a marked reduction in I??B phosphorylation and degradation was observed following ??catenin knockdown. The expression levels of the LTA?induced proinflammatory cytokines were also significantly reduced following ??catenin siRNA. These results suggest that ??catenin has a significant role in the regulation of NF??B activity and proinflammatory cytokine expression during the LTA-induced inflammatory response of bronchial epithelial cells. PMID:26095159

  12. CREB is required for cAMP/PKA signals upregulating neuropathy target esterase expression.

    PubMed

    Chen, Jia-Xiang; Wu, Yi-Jun

    2013-04-01

    Neuropathy target esterase (NTE), which has been proposed as the primary target of organophosphorus compounds that cause delayed neuropathy with degeneration of nerve axons, is expressed primarily in neural cells but is also detected in non-neural cells. However, little is known about the regulation of NTE gene in cells. We found that a cyclic-AMP (cAMP)-response element (CRE) exists in the 5' flanking sequence of NTE gene in HeLa cells, which implies that NTE may be regulated by the transcription factor cAMP-response element-binding protein (CREB). In the study, knockdown of CREB decreased the protein and mRNA levels of NTE and inhibited the upregulation by cAMP/PKA signaling. Moreover, we observed that knockdown of CREB significantly decreased luciferase activity of the NTE gene promoter, while it had no effect on that of the CREB binding sites of mutated NTE gene promoter and truncated NTE gene promoter lacking the CREB binding site. cAMP/PKA signals could increase NTE reporter gene activity, while knockdown of CREB inhibited the increase. We found that the transcription factor CREB can bind to the promoter sequence of NTE by chromatin immunoprecipitation. In conclusion, we provided evidence that CREB is required for cAMP/PKA signals upregulating NTE expression in HeLa cells. PMID:23517531

  13. Krüppel-Like Factor 6 Rendered Rat Schwann Cell More Sensitive to Apoptosis via Upregulating FAS Expression

    PubMed Central

    Zhang, Lixing; Wang, Wenjing; Zhu, Hao; Ding, Wenlong

    2013-01-01

    Krüppel-like factor 6 (KLF6) is a tumor suppressor gene and play a role in the regulation of cell proliferation and apoptosis. After the peripheral nerve injury (PNI), the microenvironment created by surrounding Schwann cells (SCs) is a critical determinant of its regenerative potential. In this study, we examined the effects of KLF6 on SCs responses during PNI. Both KLF6 mRNA and protein expression levels were upregulated in the injured sciatic nerve, and immunofluorescence results showed that many KLF6-positive cells simultaneously expressed the SC markers S-100 and p75NTR. The apoptosis inducers TNF? and cisplatin upregulated KLF6 expression in primary cultured SCs and the SC line RSC96. Although KLF6 overexpression exacerbated cisplatin- and TNF?-induced apoptosis, expression levels of the apoptosis regulators Bcl2 and Bax were not significantly affected in either KLF6-overexpressing or KLF6-depleted RSC96 cells. Realtime PCR arrays and qRT-PCR demonstrated that KLF6 overexpression upregulated four pro-apoptotic genes, FAS, TNF, TNFSF12, and PYCARD, and inhibited expression of the anti-apoptotic IL10 gene expression. Further analysis revealed that FAS protein expression was positively correlated with KLF6 expression in SCs. These data suggest that KLF6 upregulation may render SCs more vulnerable to apoptosis after injury via upregulating FAS expression. PMID:24324791

  14. Efficacy of QCDCR formulated CpG ODN 2007 in Nile tilapia against Streptococcus iniae and identification of upregulated genes.

    PubMed

    Pridgeon, Julia W; Klesius, Phillip H; Mu, Xingjiang; Yancey, Robert J; Kievit, Michele S; Dominowski, Paul J

    2012-01-15

    The potential of using a QCDCR (quilA:cholesterol:dimethyl dioctadecyl ammonium bromide:carbopol:R1005 glycolipid) formulated CpG oligodeoxynucleotide (ODN), ODN 2007, to confer protection in Nile tilapia against Streptococcus iniae infection was evaluated in this study. At two days post treatment, QCDCR formulated ODN 2007 elicited significant (P<0.05) protection to Nile tilapia, with relative percent survival of 63% compared to fish treated by QCDCR alone. To understand the molecular mechanisms involved in the protective immunity elicited by ODN 2007, suppression subtractive cDNA hybridization technique was used to identify upregulated genes induced by ODN 2007. A total of 69 expressed sequence tags (ESTs) were identified from the subtractive cDNA library. Quantitative PCR revealed that 44 ESTs were significantly (P<0.05) upregulated by ODN 2007, including 29 highly (>10-fold) and 15 moderately (<10-fold) upregulated ESTs. Of all ESTs, putative peroxisomal sarcosine oxidase was upregulated the highest. The 69 ESTs only included six genes that had putative functions related to immunity, of which only two (putative glutaredoxin-1 and carboxypeptidase N catalytic chain) were confirmed to be significantly upregulated. Our results suggest that the protection elicited by ODN 2007 is mainly through innate immune responses directly or indirectly related to immunity. PMID:22129787

  15. Arabidopsis CALCIUM-DEPENDENT PROTEIN KINASE8 and CATALASE3 Function in Abscisic Acid-Mediated Signaling and H2O2 Homeostasis in Stomatal Guard Cells under Drought Stress[OPEN

    PubMed Central

    Wang, Cun; Zhang, Wen-Zheng

    2015-01-01

    Drought is a major threat to plant growth and crop productivity. Calcium-dependent protein kinases (CDPKs, CPKs) are believed to play important roles in plant responses to drought stress. Here, we report that Arabidopsis thaliana CPK8 functions in abscisic acid (ABA)- and Ca2+-mediated plant responses to drought stress. The cpk8 mutant was more sensitive to drought stress than wild-type plants, while the transgenic plants overexpressing CPK8 showed enhanced tolerance to drought stress compared with wild-type plants. ABA-, H2O2-, and Ca2+-induced stomatal closing were impaired in cpk8 mutants. Arabidopsis CATALASE3 (CAT3) was identified as a CPK8-interacting protein, confirmed by yeast two-hybrid, coimmunoprecipitation, and bimolecular fluorescence complementation assays. CPK8 can phosphorylate CAT3 at Ser-261 and regulate its activity. Both cpk8 and cat3 plants showed lower catalase activity and higher accumulation of H2O2 compared with wild-type plants. The cat3 mutant displayed a similar drought stress-sensitive phenotype as cpk8 mutant. Moreover, ABA and Ca2+ inhibition of inward K+ currents were diminished in guard cells of cpk8 and cat3 mutants. Together, these results demonstrated that CPK8 functions in ABA-mediated stomatal regulation in responses to drought stress through regulation of CAT3 activity. PMID:25966761

  16. Upregulated Ras/Raf/ERK1/2 signaling pathway: a new hope in the repair of spinal cord injury

    PubMed Central

    Liu, Tao; Cao, Fu-jiang; Xu, Dong-dong; Xu, Yun-qiang; Feng, Shi-qing

    2015-01-01

    An increasing number of studies report that the Ras/Raf/extracellular signal-regulated kinase 1/2 (ERK1/2) signaling pathway has a death-promoting apoptotic function in neural cells. We hypothesized that the Ras/Raf/ERK1/2 signaling pathway may be abnormally regulated in rat injured spinal cord models. The weight drop method was used to establish rat spinal cord injury at T9. Western blot analysis and immunohistochemical staining revealed Ras expression was dramatically elevated, and the phosphorylations of A-Raf, B-Raf and C-Raf were all upregulated in the injured spinal cord. Both mitogen-activated protein kinase kinase 1/2 and ERK1/2, which belong to the Ras/Raf signaling kinases, were upregulated. These results indicate that Ras/Raf/ERK1/2 signaling may be upregulated in injured spinal cord and are involved in recovery after spinal cord injury.

  17. PKC? Synergizes with TLR-Dependent TRAF6 Signaling Pathway to Upregulate MUC5AC Mucin via CARMA1

    PubMed Central

    Jono, Hirofumi; Lim, Jae Hyang; Xu, Haidong; Li, Jian-Dong

    2012-01-01

    CARD-containing MAGUK protein 1 (CARMA1) plays a crucial role in regulating adaptive immune responses upon T-cell receptor (TCR) activation in T cells. Its role in regulating host mucosal innate immune response such as upregulation of mucin remains unknown. Here we show that CARMA1 acts as a key signaling mediator for synergistic upregulation of MUC5AC mucin by bacterium nontypeable Haemophilus influenzae (NTHi) and phorbol ester PMA in respiratory epithelial cells. NTHi-induced TLR-dependent TRAF6-MKK3-p38 MAPK signaling pathway synergizes with PKC?-MEK-ERK signaling pathway. CARMA1 plays a crucial role in mediating this synergistic effect via TRAF6, thereby resulting in synergistic upregulation of MUC5AC mucin. Thus our study unveils a novel role for CARMA1 in mediating host mucosal innate immune response. PMID:22303480

  18. Upregulation of cytosolic phosphoenolpyruvate carboxykinase is a critical metabolic event in melanoma cells that repopulate tumors.

    PubMed

    Li, Yong; Luo, Shunqun; Ma, Ruihua; Liu, Jing; Xu, Pingwei; Zhang, Huafeng; Tang, Ke; Ma, Jingwei; Zhang, Yi; Liang, Xiaoyu; Sun, Yanling; Ji, Tiantian; Wang, Ning; Huang, Bo

    2015-04-01

    Although metabolic defects have been investigated extensively in differentiated tumor cells, much less attention has been directed to the metabolic properties of stem-like cells that repopulate tumors [tumor-repopulating cells (TRC)]. Here, we show that melanoma TRCs cultured in three-dimensional soft fibrin gels reprogram glucose metabolism by hijacking the cytosolic enzyme phosphoenolpyruvate carboxykinase (PCK1), a key player in gluconeogenesis. Surprisingly, upregulated PCK1 in TRCs did not mediate gluconeogenesis but promoted glucose side-branch metabolism, including in the serine and glycerol-3-phosphate pathways. Moreover, this retrograde glucose carbon flow strengthened rather than antagonized glycolysis and glucose consumption. Silencing PCK1 or inhibiting its enzymatic activity slowed the growth of TRCs in vitro and impeded tumorigenesis in vivo. Overall, our work unveiled metabolic features of TRCs in melanoma that have implications for targeting a unique aspect of this disease. Cancer Res; 75(7); 1191-6. ©2015 AACR. PMID:25712344

  19. Cytohesin-3 is upregulated in hepatocellular carcinoma and contributes to tumor growth and vascular invasion

    PubMed Central

    Fu, Ying; Li, Jun; Feng, Ming-Xuan; Yang, Xiao-Mei; Wang, Ya-Hui; Zhang, Yan-Li; Qin, Wenxin; Xia, Qiang; Zhang, Zhi-Gang

    2014-01-01

    Hepatocellular carcinoma (HCC) is a malignant tumor with high morbidity and mortality, and is characterized by high potential for metastasis and recurrence. The outcome of it is still poor due to lacking of targeted therapeutic strategies. There is an urgent need to find new therapeutic targets for interventions against HCC metastasis and recurrence. In the present study, we found cytohesin-3, a member of the cytohesin family, was upregulated in HCC tissues, and its expression was negatively correlated with the overall survival and relapse-free survival of HCC patients. Further clinicopathological correlation analysis revealed that cytohesin-3 expression was related with tumor size and vascular invasion. And in vitro studies revealed that knock-down of cytohesin-3 suppressed HCC cells proliferation and migration. These results suggest that cytohesin-3 may act as a novel prognostic factor of HCC, and it might also be useful to exploit targeted therapeutic drugs against HCC growth and metastasis. PMID:24966920

  20. Molecular cloning and functional analysis of a novel oncogene, cancer-upregulated gene 2 (CUG2)

    SciTech Connect

    Lee, Soojin [Department of Microbiology, Chungnam National University, Daejeon 305-764 (Korea, Republic of)]. E-mail: leesoojin@cnu.ac.kr; Gang, Jingu [Department of Internal Medicine, Brain Korea 21 Project for Medical Science, Yonsei University College of Medicine, Seoul (Korea, Republic of); Jeon, Sun Bok [LG Life Sciences, Ltd./R and D Park, Daejeon (Korea, Republic of); Choo, Seung Ho [LG Life Sciences, Ltd./R and D Park, Daejeon (Korea, Republic of); Lee, Bogman [LG Life Sciences, Ltd./R and D Park, Daejeon (Korea, Republic of); Kim, Young-Gun [LG Life Sciences, Ltd./R and D Park, Daejeon (Korea, Republic of); Lee, Yang Soon [Korea Research Institute of Bioscience and Biotechnology, Daejeon 305-333 (Korea, Republic of); Jung, Jinyoung [Department of Microbiology, Chungnam National University, Daejeon 305-764 (Korea, Republic of); Song, Si Young [Department of Internal Medicine, Brain Korea 21 Project for Medical Science, Yonsei University College of Medicine, Seoul (Korea, Republic of); Koh, Sang Seok [Korea Research Institute of Bioscience and Biotechnology, Daejeon 305-333 (Korea, Republic of)]. E-mail: sskoh@kribb.re.kr

    2007-08-31

    We examined genome-wide differences in gene expression between tumor biopsies and normal tissues in order to identify differentially regulated genes in tumors. Cancer-upregulated gene 2 (CUG2) was identified as an expressed sequence tag (EST) that exhibits significant differential expression in multiple human cancer types. CUG2 showed weak sequence homology with the down-regulator of transcription 1 (DR1) gene, a human transcription repressor. We found that EGFP-CUG2 fusion proteins were predominantly localized in the nucleus, suggesting their putative role in gene regulation. In addition, CUG2-overexpressing mouse fibroblast cells exhibited distinct cancer-specific phenotypes in vitro and developed into tumors in nude mice. Taken together, these findings suggest that CUG2 is a novel tumor-associated gene that is commonly activated in various human cancers and exhibits high transforming activities; it possibly belongs to a transcription regulator family that is involved in tumor biogenesis.