DOCSLIB.ORG

Endogenous Intracellular Glutathionyl Radicals Are Generated In

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Endogenous Intracellular Glutathionyl Radicals Are Generated In Proc. Natl. Acad. Sci. USA Vol. 92, pp. 4582-4586, May 1995 Biochemistry Endogenous intracellular glutathionyl radicals are generated in neuroblastoma cells under hydrogen peroxide oxidative stress (free radical/spin trapping/electron paramagnetic resonance/glutathione/N-acetyl-L-cysteine) HAHN-S. KWAK*, HYUNG-S. YIM, P. BOON CHOCK, AND MOON B. YIMt Laboratory of Biochemistry, National Heart, Lung, and Blood Institute, National Institutes of Health, Building 3, Room 202, Bethesda, MD 20892 Communicated by Earl R. Stadtman, National Heart, Lung, and Blood Institute, Bethesda, MD, January 12, 1995 ABSTRACT We report the detection of endogenous in- In addition to the protection of cells by antioxidant enzymes, tracellular glutathionyl (GS') radicals in the intact neuro- low molecular weight antioxidant compounds are thought to blastoma cell line NCB-20 under oxidative stress. Spin- be involved in the protection of biomolecules against reactive trapping and electron paramagnetic resonance (EPR) spec- free radical species, such as hydroxyl radicals ("OH) or other troscopic methods were used for monitoring the radicals. The radicals from xenobiotics, which cannot be removed by en- cells incubated with the spin trap 5,5-dimethyl-l-pyrroline zymes. Cellularly abundant reduced glutathione (GSH) is an 1-oxide (DMPO) were challenged with H202 generated by the important molecule in this regard because it functions both as enzymic reaction of glucose/glucose oxidase. These cells a substrate or cofactor of antioxidant enzymes and as a good exhibit the EPR spectrum of the GS- radical adduct of DMPO radical scavenger (10-14). As a radical scavenger, glutathione (DMPO-'SG) without exogenous reduced glutathione (GSH). repairs free radical sites, R-, by the following reaction: The identity ofthis radical adduct was confirmed by observing hyperfine coupling constants identical to previously reported GSH + R GS + RH [1] values in in vitro studies, which utilized known enzymic where GS" is the glutathionyl radical and R* represents *OH, reactions, such as horseradish peroxidase and Cu/Zn super- other reactive radicals, or radical sites in proteins and DNA oxide dismutase, with GSH and H202 as substrates. The generated by cascading reactions (15, 16). When GSH defi- formation of the GS' radicals required viable cells and con- ciency is produced in newborn rats or guinea pigs, the animals tinuous biosynthesis of GSH. No significant effect on the develop multiorgan failure, which is directly related to the loss resonance amplitude by the addition of a membrane- of essential antioxidant capacity (13, 14, 17, 18). Also, the impermeable paramagnetic broadening agent indicated that activation of NF-KB is inhibited by the addition of N-acetyl- these radicals were located inside the intact cell. N-Acetyl-L- L-cysteine (NAC), which serves as an oxygen radical scavenger cysteine (NAC)-treated cells produced NAC-derived free rad- and as a precursor for GSH biosynthesis (4-7). Most of the icals (NAC-) in place of GS' radicals. The time course studies reaction rates involving GSH in reaction 1 are diffusion showed that DMPO-'SG formation exhibited a large increase controlled (19, 20). Therefore, the glutathionyl radical or its in its concentration after a lag period, whereas DMPO-NAC° cascading radicals, rather than the initial oxygen free radicals, formation from NAC-treated cells did not show this sudden are likely the predominant intracellular radical species. increase. These results were discussed in terms of the limit of We attempted to detect and identify free radicals formed antioxidant enzyme defenses in cells and the potential role of under H202 stress in intact cells by using electron paramag- the GS' radical burst in activation ofthe transcription nuclear netic resonance (EPR) and spin-trapping methods. Our results factor NF-KB in response to oxidative stress. show that H202 stress generates endogenous intracellular GS' radicals in intact cells and NAC-originated thiyl radicals Oxidative stress is believed to increase the concentration of (NAC') in NAC-treated cells. In addition, GS' formation reactive oxygen free radicals in vivo, which are responsible, at exhibited a large increase in its concentration after a lag least in part, for a wide variety of degenerative processes (1, 2). period, whereas NACG formation did not show this sudden Recent studies also demonstrated that treatment of cultured increase. cells with H202 or other stimuli for oxidative stress leads to the activation of nuclear factor KB (NF-KB) (3-8) and, in turn, MATERIALS AND METHODS induces expression and replication of the human immunode- ficiency virus (3-7). These investigations suggest that reactive Materials. The spin trap 5,5-dimethyl-l-pyrroline 1-oxide oxygen intermediates or free radicals serve as messengers for (DMPO), chromium oxalate, and 2-vinylpyridine were pur- activation of transcription factors. Although pathological and chased from Aldrich. Horseradish peroxidase (HRP) (type in vitro studies lead to the suggestion that toxic free radicals are VI), EDTA, GSH, 5,5'-dithiobis(2-nitrobenzoic acid), and responsible for oxidative damage, more understanding is re- cytochrome c (type VI, from horse heart) were obtained from quired at the cellular level about the mechanisms responsible Sigma. Glucose oxidase, glutathione peroxidase (bovine eryth- for the formation of oxygen radicals, their cascading reactions, rocytes), glutathione reductase (yeast), NADPH, oxidized and cellular signals to genomic levels for activation of defense glutathione, deoxycholate, and NAC were purchased from or repair systems. The fundamental importance in this respect Calbiochem. Cu/Zn superoxide dismutase (Cu/Zn-SOD), is to find whether free radicals exist in viable cells and whether xanthine oxidase, and leupeptin were purchased from Boehr- oxidative stress increases the concentration of the free radicals inger Mannheim; Chelex 100 resin and SDS were from Bio- in viable cells. However, there is a paucity of direct detection and structural identification of free radicals formed in intact Abbreviations: GSH, reduced glutathione; DMPO, 5,5-dimethyl-1- cells because of inherent experimental difficulties (9). pyrroline 1-oxide; NAC, N-acetyl-L-cysteine; HRP, horseradish per- oxidase; SOD, superoxide dismutase; EPR, electron paramagnetic resonance. The publication costs of this article were defrayed in part by page charge *Present address: Department of Genetic Engineering, Pai-Chai Uni- payment. This article must therefore be hereby marked "advertisement" in versity, Taejon, Korea. accordance with 18 U.S.C. §1734 solely to indicate this fact. tTo whom reprint requests should be addressed. 4582 Downloaded by guest on October 1, 2021 Biochemistry: Kwak et aL Proc. Natl. Acad. Sci. USA 92 (1995) 4583 were Rad; and H202 (30%) and picric acid from Fisher. A A A NCB20 Dulbecco's modified Eagle's medium (DMEM), fetal bovine serum (FBS), and trypan blue were obtained from GIBCO. BCA protein assay reagent was from Pierce, and Triton X-100 B HRP+GSH+H202 was from Research Products International. All solutions were \ treated with Chelex 100. The pH values of the bicarbonate buffer (23.5 mM) and of bicarbonate-buffered saline (BBS) were adjusted to 7.4 by bubbling 5% C02/95% N2 or air/gas mixture. Methods. The spin-trapping method utilizes an addition reaction of transient free radicals to diamagnetic spin traps to produce relatively stable spin-trap-free radical adducts (21, 22). The identity of the free radical can be determined from hyperfine coupling constants of the spin adduct by EPR A was used in this EPR spectroscopy. spin trap, DMPO, study. -H202 spectra were recorded on a Bruker ESP 300 spectrometer with E a TM11o resonator. The spectrometer settings were as follows: modulation amplitude, 1.6 G; conversion time, 41 ms; time F -SOD constant, 0.328 s; resolution of field axis, 2048 points; sweep width, 100 G; sweep time, 84 s; accumulation, two times. II I i Cell Preparation. NCB-20 cells (kindly provided by M. 3440 3460 3480 3500 3520 Nirenberg, National Institutes of Health, Bethesda, MD) were Gauss grown in monolayer in DMEM supplemented with 10% (vol/vol) FBS on culture dishes in 5% C02/95% air. At FIG. 1. EPR spectra of DMPO-free radical adducts observed in confluency, the medium was removed from the dishes and the NCB-20 cells and in known enzymic reactions. Spectrum A, the EPR attached cells were washed twice with Chelex 100-treated BBS sample from NCB-20 cells was recorded 100 min after addition of at were in BBS 100 glucose oxidase at 25°C under the conditions described in Materials pH 7.4. Incubations continued containing and Methods. the reaction mixture under anaerobic min at of cells was deter- Spectrum B, mM DMPO for 50 370C. Viability conditions contained 0.1 mg of HRP per ml, 0.05 mM H202, 10 mM mined by the trypan blue exclusion method with cells being GSH, and 60 mM DMPO in 20 mM Hepes buffer at pH 7.2. The removed by gentle scraping from plates. The medium was spectrum was taken with the sample in the quartz flat cell positioned removed bycentrifugation, glucose and glucose oxidase in BBS in a vertically mounted TM110o resonator 1 min after the reaction was were added, and cells were incubated again for 30 min at 370C. initiated by injecting H202. The spectrometer settings were identical The EPR sample (140 t1l) contains 1.0 x 107 cells, 7.5 mM to those in spectrum A except conversion time was 20.48 ms and glucose, and 200 units of glucose oxidase in a gas-permeable resolution was 4096 points. Spectrum C, the reaction mixture con- Teflon tube (0.032-inch i.d., 0.002-inch wall; Zeus Industrial tained 0.1 mg of Cu/Zn-SOD per ml, 2.0 mM H202, 20 mM GSH, and The under these 10 mM DMPO in 23.5 mM bicarbonate buffer at pH 7.6. Other Products, Orangeburg, SC). H202 produced conditions are identical to those in B.
Load more

Recommended publications
  • Janne Bjmmtvedt Buhaug Investigation of the Chemistry of Liquid H2S Scavengers ,- DISC-LAIMER
    Janne Bjmmtvedt Buhaug Investigation of the Chemistry of Liquid H2S Scavengers ,- DISC-LAIMER Portions of this document may be illegible in electronic image products. Images are produced from the best available original document. Janne Bjamtvedt Buhaug INVESTIGATION OF THE CHEMISTRY OF LIQUIDH2S SCAVENGERS DEPARTMENT OF CHEMISTRY NORWEGIAN UNIVERSITY OF SCIENCE & TECHNOLOGY "u Preface The work presented in this dissertation has been executed at the Department of Chemistry, the Norwegian University of Science and Technology in Trond- heim, fiom January 1999 to June 2002. Statoil ASA initiated this work, and I would like to thank them for letting me work on their project. Statoil and the Norwegian Research Council are gratellly acknowledged for their generous financial support. I would like to express my most sincere gratitude to my supervisor, Professor Jan M. Bakke, for his great enthusiasm and belief in me and my work. I am deeply grateful to my friends and colleagues at the Department for many hours of small-talk, fruitful discussions and valuable help during my studies. Particularly, I would particularly like to thank siv.ing. Ingrid Sletvold and sivhg. Bjart Frode Lutnzzs for spending hours reading through this thesis. All your comments have been greatly appreciated. Dr.ing. Einar Skarstad Egeland was very helpful in establishing the WPAC names of many of my compounds, and he is gratefully acknowledged. Finally, I would like to express my gratitude to my family for the many encour- aging phone calls during my many years of education. Lastly, I would like to thank my husband, Halvard, for his love and support, and for colourful ideas for my work.
    [Show full text]
  • Redalyc.Antioxidant and Scavenging Activity of Skyrin on Free Radical And
    Avances en Química ISSN: 1856-5301 [email protected] Universidad de los Andes Venezuela Vargas, Franklin; Rivas, Carlos; Zoltan, Tamara; López, Verónica; Ortega, Jessenia; Izzo, Carla; Pineda, María; Medina, José; Medina, Ernesto; Rosales, Luís Antioxidant and scavenging activity of skyrin on free radical and some reactive oxygen species Avances en Química, vol. 3, núm. 1, enero-abril, 2008, pp. 7-14 Universidad de los Andes Mérida, Venezuela Disponible en: http://www.redalyc.org/articulo.oa?id=93330103 Cómo citar el artículo Número completo Sistema de Información Científica Más información del artículo Red de Revistas Científicas de América Latina, el Caribe, España y Portugal Página de la revista en redalyc.org Proyecto académico sin fines de lucro, desarrollado bajo la iniciativa de acceso abierto 7 www.saber.ula.ve/avancesenquimica Avances en Química, 3(1), 7-14 (2008) Artículo Científico Antioxidant and scavenging activity of skyrin on free radical and some reactive oxygen species. Franklin Vargas *1, Carlos Rivas1, Tamara Zoltan1, Verónica López1, Jessenia Ortega1, Carla Izzo1, María Pineda1, José Medina2, Ernesto Medina3, Luís Rosales *3 1) Laboratorio de Fotoquímica, Instituto Venezolano de Investigaciones Científicas (I.V.I.C.) 2) Centro de Química, I.V.I.C. 3) Laboratorio de Ecofisiología Vegetal, Centro de Ecología, I.V.I.C., Caracas, Venezuela. Phone: 0212-5041338, Fax: 0212-5041350 (*) [email protected] Recibido: 28/11/2007 Revisado: 10/01/2008 Aceptado: 10/03/2008 --------------------------------------------------------------------------------------------------------------------- Resumen: El skyrin es un producto natural proveniente de algunas especies botánicas (hongos) y es uno de los primeros agentes antidiabéticos no-peptídico de pequeño peso molecular. El objetivo de este estudio fue el de investigar .
    [Show full text]
  • Uncommon Fatty Acids and Cardiometabolic Health
    Review Uncommon Fatty Acids and Cardiometabolic Health Kelei Li 1, Andrew J. Sinclair 2,3, Feng Zhao 1 and Duo Li 1,3,* 1 Institute of Nutrition and Health, Qingdao University, Qingdao 266021, China; [email protected] (K.L.); [email protected] (F.Z.) 2 Faculty of Health, Deakin University, Locked Bag 20000, Geelong, VIC 3220, Australia; [email protected] 3 Department of Nutrition, Dietetics and Food, Monash University, Notting Hill, VIC 3168, Australia * Correspondence: [email protected]; Tel.: +86-532-8299-1018 Received: 7 September 2018; Accepted: 18 October 2018; Published: 20 October 2018 Abstract: Cardiovascular disease (CVD) is a major cause of mortality. The effects of several unsaturated fatty acids on cardiometabolic health, such as eicosapentaenoic acid (EPA) docosahexaenoic acid (DHA), α linolenic acid (ALA), linoleic acid (LA), and oleic acid (OA) have received much attention in past years. In addition, results from recent studies revealed that several other uncommon fatty acids (fatty acids present at a low content or else not contained in usual foods), such as furan fatty acids, n-3 docosapentaenoic acid (DPA), and conjugated fatty acids, also have favorable effects on cardiometabolic health. In the present report, we searched the literature in PubMed, Embase, and the Cochrane Library to review the research progress on anti-CVD effect of these uncommon fatty acids. DPA has a favorable effect on cardiometabolic health in a different way to other long-chain n-3 polyunsaturated fatty acids (LC n-3 PUFAs), such as EPA and DHA. Furan fatty acids and conjugated linolenic acid (CLNA) may be potential bioactive fatty acids beneficial for cardiometabolic health, but evidence from intervention studies in humans is still limited, and well-designed clinical trials are required.
    [Show full text]
  • Hydrogen As a Novel and Effective Treatment of Acute Carbon Monoxide Poisoning
    ARTICLE IN PRESS Medical Hypotheses xxx (2010) xxx–xxx Contents lists available at ScienceDirect Medical Hypotheses journal homepage: www.elsevier.com/locate/mehy Hydrogen as a novel and effective treatment of acute carbon monoxide poisoning Meihua Shen, Jian He, Jianmei Cai, Qiang Sun, Xuejun Sun, Zhenglu Huo * Second Military Medical University, 800 Xiangyin Road, Shanghai 200433, PR China article info summary Article history: Hydrogen is a major component of interstellar space and the fuel that sustains the stars. However, it is Received 19 February 2010 seldom regarded as a therapeutic gas. A recent study provided evidence that hydrogen inhalation exerted Accepted 23 February 2010 antioxidant and anti-apoptotic effects and protected the brain against ischemia–reperfusion injury by Available online xxxx selectively reducing hydroxyl radical and peroxynitrite. It has been known that the mechanisms under- lying the brain injury after acute carbon monoxide poisoning are interwoven with multiple factors including oxidative stress, free radicals, and neuronal nitric oxide synthase as well as abnormal inflam- matory responses. Studies have shown that free radical scavengers can improve the neural damage. Based on the findings abovementioned, we hypothesize that hydrogen therapy may be an effective, simple, economic and novel strategy in the treatment of acute carbon monoxide poisoning. Ó 2010 Elsevier Ltd. All rights reserved. Introduction prevents neural death. Other researchers have showed that hydro- gen can also improve myocardial, hepatic ischemia–reperfusion in- Hydrogen is the simplest and most essential chemical element, jury, neonatal hypoxia–ischemia, Parkinson’s disease, oxidative composing nearly 75% of the universe’s elemental matter. It is a stress induced cognitive decline, etc.
    [Show full text]
  • Comparative Metabolic Profile of Maize Genotypes Reveals the Tolerance Mechanism Associated 2 Under Combined Stresses
    bioRxiv preprint doi: https://doi.org/10.1101/2020.06.11.127928; this version posted June 12, 2020. The copyright holder for this preprint (which was not certified by peer review) is the author/funder. All rights reserved. No reuse allowed without permission. 1 Comparative metabolic profile of maize genotypes reveals the tolerance mechanism associated 2 under combined stresses. 3 4 Suphia Rafique-1 5 Department of Biotechnology, Faculty of Chemical and Life Sciences, Jamia Hamdard, New Delhi- 6 110062. India 7 -1 Corresponding Author email: [email protected] 8 9 Abstract: 10 Drought, heat, high temperature, waterlogging, low-N stress, and salinity are the major 11 environmental constraints that limit plant productivity. In tropical regions maize grown during the 12 summer rainy season, and often faces irregular rains patterns, which causes drought, and 13 waterlogging simultaneously along with low-N stress and thus affects crop growth and 14 development. The two maize genotypes CML49 and CML100 were subjected to combination of 15 abiotic stresses concurrently (drought and low-N / waterlogging and low-N). Metabolic profiling of 16 leaf and roots of two genotypes was completed using GC-MS technique. The aim of study to reveal 17 the differential response of metabolites in two maize genotypes under combination of stresses and 18 to understand the tolerance mechanism. The results of un-targeted metabolites analysis show, the 19 accumulated metabolites of tolerant genotype (CML49) in response to combined abiotic stresses 20 were related to defense, antioxidants, signaling and some metabolites indirectly involved in nitrogen 21 restoration of the maize plant. Alternatively, some metabolites of sensitive genotype (CML100) 22 were regulated in response to defense, while other metabolites were involved in membrane 23 disruption and also as the signaling antagonist.
    [Show full text]
  • Antioxidants: Classification, Natural Sources, Activity/Capacity Measurements, and Usefulness for the Synthesis of Nanoparticles
    materials Review Antioxidants: Classification, Natural Sources, Activity/Capacity Measurements, and Usefulness for the Synthesis of Nanoparticles Jolanta Flieger 1,* , Wojciech Flieger 2 , Jacek Baj 2 and Ryszard Maciejewski 2 1 Department of Analytical Chemistry, Medical University of Lublin, Chod´zki4A, 20-093 Lublin, Poland 2 Chair and Department of Anatomy, Medical University of Lublin, Jaczewskiego 4, 20-090 Lublin, Poland; [email protected] (W.F.); [email protected] (J.B.); [email protected] (R.M.) * Correspondence: j.fl[email protected]; Tel.: +48-81448-7182 Abstract: Natural extracts are the source of many antioxidant substances. They have proven useful not only as supplements preventing diseases caused by oxidative stress and food additives preventing oxidation but also as system components for the production of metallic nanoparticles by the so-called green synthesis. This is important given the drastically increased demand for nanomaterials in biomedical fields. The source of ecological technology for producing nanoparticles can be plants or microorganisms (yeast, algae, cyanobacteria, fungi, and bacteria). This review presents recently published research on the green synthesis of nanoparticles. The conditions of biosynthesis and possible mechanisms of nanoparticle formation with the participation of bacteria are presented. The potential of natural extracts for biogenic synthesis depends on the content of reducing substances. The assessment of the antioxidant activity of extracts as multicomponent mixtures is still a challenge for analytical chemistry. There is still no universal test for measuring total antioxidant capacity (TAC). There are many in vitro chemical tests that quantify the antioxidant scavenging activity of free radicals and their ability to chelate metals and that reduce free radical damage.
    [Show full text]
  • Glutathione Metabolism in Renal Cell Carcinoma Progression and Implications for Therapies
    Review Glutathione Metabolism in Renal Cell Carcinoma Progression and Implications for Therapies Yi Xiao 1,2 and David Meierhofer 1,* 1 Max Planck Institute for Molecular Genetics, Ihnestraße 63-73, 14195 Berlin, Germany 2 Freie Universität Berlin, Fachbereich Biologie, Chemie, Pharmazie, Takustraße 3, 14195 Berlin, Germany * Correspondence: [email protected]; Tel.: +49-30-8413-1567; Fax.: +49-30-8413-1960 Received: 27 June 2019; Accepted: 26 July 2019; Published: 26 July 2019 Abstract: A significantly increased level of the reactive oxygen species (ROS) scavenger glutathione (GSH) has been identified as a hallmark of renal cell carcinoma (RCC). The proposed mechanism for increased GSH levels is to counteract damaging ROS to sustain the viability and growth of the malignancy. Here, we review the current knowledge about the three main RCC subtypes, namely clear cell RCC (ccRCC), papillary RCC (pRCC), and chromophobe RCC (chRCC), at the genetic, transcript, protein, and metabolite level and highlight their mutual influence on GSH metabolism. A further discussion addresses the question of how the manipulation of GSH levels can be exploited as a potential treatment strategy for RCC. Keywords: Renal cell carcinoma (RCC); reactive oxygen species (ROS); glutathione (GSH) metabolism; cancer therapy; clear cell RCC; papillary RCC; chromophobe RCC 1. Introduction Increased reactive oxygen species (ROS) levels, including the superoxide anion, hydrogen peroxide, and hydroxyl radical, have been reported in many different cancer types. ROS can be either generated by genetic alterations and endogenous oxygen metabolism or by exogenous sources, such as UV light and radiation. ROS were long thought to be only damaging byproducts of the cellular metabolism that can negatively affect DNA, lipids, and proteins [1].
    [Show full text]
  • Advanced Oxidation Processes - Applications, Trends, Prospects - Applications, and Processes Oxidation Advanced
    Edited by Ciro Bustillo-Lecompte Advanced Oxidation Processes and - Applications, Prospects Trends, Advanced Oxidation Processes – Applications, Trends, and Prospects constitutes a comprehensive resource for civil, chemical, and environmental engineers researching in the field of water and wastewater treatment. The book covers the fundamentals, applications, and future work in Advanced Oxidation Processes (AOPs) as an Advanced Oxidation attractive alternative and a complementary treatment option to conventional methods. This book also presents state-of-the-art research on AOPs and heterogeneous catalysis Processes while covering recent progress and trends, including the application of AOPs at the Applications, Trends, and Prospects laboratory, pilot, or industrial scale, the combination of AOPs with other technologies, hybrid processes, process intensification, reactor design, scale-up, and optimization. The book is divided into four sections: Introduction to Advanced Oxidation Processes, General Concepts of Heterogeneous Catalysis, Fenton and Ferrate in Wastewater Edited by Ciro Bustillo-Lecompte Treatment, and Industrial Applications, Trends, and Prospects. ISBN 978-1-78984-890-8 Published in London, UK © 2020 IntechOpen © Aleksandr Rybak / iStock Advanced Oxidation Processes - Applications, Trends, and Prospects Edited by Ciro Bustillo-Lecompte Published in London, United Kingdom Supporting open minds since 2005 Advanced Oxidation Processes - Applications, Trends, and Prospects http://dx.doi.org/10.5772/intechopen.85681 Edited by Ciro
    [Show full text]
  • Synthesis and Scavenging Role of Furan Fatty Acids
    Synthesis and scavenging role of furan fatty acids Rachelle A. S. Lemkea, Amelia C. Petersonb, Eva C. Ziegelhoffera, Michael S. Westphallc, Henrik Tjellströmd,e, Joshua J. Coonb,d,f, and Timothy J. Donohuea,d,1 Departments of aBacteriology, bChemistry, and fBiomolecular Chemistry, University of Wisconsin–Madison, Madison, WI 53706; dGreat Lakes Bioenergy Research Center, Madison, WI 53726; cGenome Center of Wisconsin, Madison, WI 53706; and eDepartment of Plant Biology, Michigan State University, East Lansing, MI 48824 Edited by Carol A. Gross, University of California, San Francisco, CA, and approved May 5, 2014 (received for review March 31, 2014) Fatty acids play important functional and protective roles in living Despite the proposed roles of Fu-FAs, little is known about systems. This paper reports on the synthesis of a previously how they are synthesized (13). We report on proteins needed for unidentified 19 carbon furan-containing fatty acid, 10,13-epoxy- the conversion of cis unsaturated fatty acids to 19Fu-FA. We 1 11-methyl-octadecadienoate (9-(3-methyl-5-pentylfuran-2-yl)nonanoic show that a O2-inducible protein (RSP2144) is an S-adenosyl me- acid) (19Fu-FA), in phospholipids from Rhodobacter sphaeroides. thionine (SAM)-dependent methylase that synthesizes a 19-carbon We show that 19Fu-FA accumulation is increased in cells contain- methylated trans unsaturated fatty acid (19M-UFA) from cis ing mutations that increase the transcriptional response of this vaccenic acid both in vivo and in vitro. We also identify gene 1 bacterium to singlet oxygen ( O2), a reactive oxygen species gen- products needed for the O2-dependent conversion of 19M-UFA 1 erated by energy transfer from one or more light-excited donors to 19Fu-FA.
    [Show full text]
  • Molecular Mechanisms Behind Free Radical Scavengers Function Against Oxidative Stress
    antioxidants Review Molecular Mechanisms behind Free Radical Scavengers Function against Oxidative Stress Fereshteh Ahmadinejad 1, Simon Geir Møller 2,3,* , Morteza Hashemzadeh-Chaleshtori 1, Gholamreza Bidkhori 4 and Mohammad-Saeid Jami 1,* 1 Cellular and Molecular Research Center, Shahrekord University of Medical Science, Shahrekord 88157, Iran; [email protected] (F.A.); [email protected] (M.H.-C.) 2 Department of Biological Sciences, St John’s University, New York, NY 11439, USA 3 Norwegian Center for Movement Disorders, Stavanger University Hospital, Stavanger 4068, Norway 4 SciLifeLab, KTH Royal Institute of Technology, Solna 17165, Sweden; [email protected] * Correspondence: [email protected] (S.G.M.); [email protected] (M.-S.J.) Received: 27 May 2017; Accepted: 29 June 2017; Published: 10 July 2017 Abstract: Accumulating evidence shows that oxidative stress is involved in a wide variety of human diseases: rheumatoid arthritis, Alzheimer’s disease, Parkinson’s disease, cancers, etc. Here, we discuss the significance of oxidative conditions in different disease, with the focus on neurodegenerative disease including Parkinson’s disease, which is mainly caused by oxidative stress. Reactive oxygen and nitrogen species (ROS and RNS, respectively), collectively known as RONS, are produced by cellular enzymes such as myeloperoxidase, NADPH-oxidase (nicotinamide adenine dinucleotide phosphate-oxidase) and nitric oxide synthase (NOS). Natural antioxidant systems are categorized into enzymatic and non-enzymatic
    [Show full text]
  • Reduced Glutathione: a Radioprotector Or a Modulator of DNA-Repair Activity?
    Nutrients 2013, 5, 525-542; doi:10.3390/nu5020525 OPEN ACCESS nutrients ISSN 2072-6643 www.mdpi.com/journal/nutrients Review Reduced Glutathione: A Radioprotector or a Modulator of DNA-Repair Activity? Anupam Chatterjee Moleculcar Genetics Laboratory, Department of Biotechnology & Bioinformatics, North-Eastern Hill University, Shillong 793022, India; E-Mail: [email protected] or [email protected]; Tel.: +91-364-272-2403; Fax: +91-364-255-0076 Received: 14 November 2012; in revised form: 15 December 2012 / Accepted: 31 January 2013 / Published: 7 February 2013 Abstract: The tripeptide glutathione (GSH) is the most abundant intracellular nonprotein thiol, and it is involved in many cellular functions including redox-homeostatic buffering. Cellular radiosensitivity has been shown to be inversely correlated to the endogenous level of GSH. On the other hand, controversy is raised with respect to its role in the field of radioprotection since GSH failed to provide consistent protection in several cases. Reports have been published that DNA repair in cells has a dependence on GSH. Subsequently, S-glutathionylation (forming mixed disulfides with the protein–sulfhydryl groups), a potent mechanism for posttranslational regulation of a variety of regulatory and metabolic proteins when there is a change in the celluar redox status (lower GSH/GSSG ratio), has received increased attention over the last decade. GSH, as a single agent, is found to affect DNA damage and repair, redox regulation and multiple cell signaling pathways. Thus, seemingly, GSH does not only act as a radioprotector against DNA damage induced by X-rays through glutathionylation, it may also act as a modulator of the DNA-repair activity.
    [Show full text]
  • Effects of the Hydroxyl Radical Scavenger, Dimethylthiourea, on Peripheral Nerve Tissue Perfusion, Conduction Velocity and Nociception in Experimental Diabetes
    Diabetologia &2001) 44: 1161±1169 Ó Springer-Verlag 2001 Effects of the hydroxyl radical scavenger, dimethylthiourea, on peripheral nerve tissue perfusion, conduction velocity and nociception in experimental diabetes N. E.Cameron, Z.Tuck, L.McCabe, M.A.Cotter Department of Biomedical Sciences, Institute of Medical Sciences, University of Aberdeen, Scotland, UK Abstract for motor conduction was 9 mg ´ kg±1 ´ day±1. Mechan- ical and thermal nociceptive sensitivities were 18.9% Aims/hypothesis. Increased oxidative stress has been and 25.0% increased by diabetes, respectively, indi- linked to diabetic neurovascular complications, cating hyperalgesia which was 70% reduced by dim- which are reduced by antioxidants. Our aim was to ethylthiourea. Sciatic endoneurial and superior cervi- assess the contribution of hydroxyl radicals to early cal ganglion blood flows were 51.2% and 52.4% re- neuropathic changes by examining the effects of duced by diabetes and there was an approximately treatment with the specific scavenger, dimethylthiou- 80% improvement with treatment. rea, on nerve function and neural tissue blood flow in Conclusion/interpretation. Hydroxyl radicals seem to diabetic rats. make a major contribution to neuropathy and vascul- Methods. Diabetes was induced by streptozotocin. opathy in diabetic rats. Treatment with the hydroxyl Measurements comprised sciatic nerve motor and scavenger, dimethylthiourea, was highly effective. saphenous nerve sensory conduction velocity. Re- The data suggest that the development of potent hy- sponses to noxious mechanical and thermal stimuli droxyl radical scavengers suitable for use in man were estimated by Randall-Sellito and Hargreaves could markedly enhance the potential therapeutic tests respectively. Sciatic nerve and superior cervical value of an antioxidant approach to the treatment of ganglion blood flow were measured by hydrogen diabetic neuropathy and vascular disease.
    [Show full text]