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Curimbaba T, Almeida-Junior L, Chagas A, Quaglio A, Herculano A, Di Stasi L. Prebiotic, antioxidant and anti-inflammatory properties of edible Amazon fruits. FOOD BIOSCI 2020. [DOI: 10.1016/j.fbio.2020.100599] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
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2
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Tanimoto A, Witaicenis A, Caruso ÍP, Piva HM, Araujo GC, Moraes FR, Fossey MC, Cornélio ML, Souza FP, Di Stasi LC. 4-Methylesculetin, a natural coumarin with intestinal anti-inflammatory activity, elicits a glutathione antioxidant response by different mechanisms. Chem Biol Interact 2020; 315:108876. [DOI: 10.1016/j.cbi.2019.108876] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2019] [Revised: 10/06/2019] [Accepted: 10/24/2019] [Indexed: 01/26/2023]
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3
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Simon F, Szabó M, Fábián I. pH controlled byproduct formation in aqueous decomposition of N-chloro-α-alanine. JOURNAL OF HAZARDOUS MATERIALS 2019; 362:286-293. [PMID: 30243251 DOI: 10.1016/j.jhazmat.2018.09.004] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/10/2018] [Revised: 08/09/2018] [Accepted: 09/02/2018] [Indexed: 06/08/2023]
Abstract
N-chloro-amino acids are readily formed in chlorination water treatment technologies. These reactions are also important in biological systems where HOCl plays an important role in the defense mechanism against invading pathogens. The intermediates and the products formed are of primary concern because they may have significant biological activities. In order to clarify intimate details and resolve discrepancies in the literature, the decomposition kinetics of N-chloro-α-alanine (MCA) was studied in the neutral - alkaline pH range by UV-vis spectrophotometry and 1H-NMR method. In contrast to earlier reports, the decomposition reaction proceeds via two distinct reaction paths: kobs1 = kOH[OH-] + k, where kOH = (1.38 ± 0.02) × 10-2 M-1s-1 and k = (2.95 ± 0.09) × 10-4 s-1. In slightly alkaline solution, the sole product is acetaldehyde. Under alkaline conditions, the main product is pyruvate ion, however, N-acetyl-α-alanine is also formed in a subsequent reaction sequence. A detailed kinetic model is postulated which involves the rate determining dissociation of MCA into Cl- and ethanimine which produces acetaldehyde in further reaction steps. Via the OH- assisted path, first a carbanion is formed which undergoes dechlorination and produces iminopropionate ion. This species is transformed into pyruvate ion through hydration and deamination steps.
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Affiliation(s)
- Fruzsina Simon
- Department of Inorganic and Analytical Chemistry, University of Debrecen, Debrecen, Hungary
| | - Mária Szabó
- Department of Inorganic and Analytical Chemistry, University of Debrecen, Debrecen, Hungary.
| | - István Fábián
- Department of Inorganic and Analytical Chemistry, University of Debrecen, Debrecen, Hungary; MTA-DE Redox and Homogeneous Catalytic Reaction Mechanisms Research Group, University of Debrecen, Debrecen, Hungary
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4
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Myeloperoxidase in the inflamed colon: A novel target for treating inflammatory bowel disease. Arch Biochem Biophys 2018; 645:61-71. [DOI: 10.1016/j.abb.2018.03.012] [Citation(s) in RCA: 104] [Impact Index Per Article: 17.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2018] [Revised: 03/08/2018] [Accepted: 03/12/2018] [Indexed: 12/17/2022]
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5
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Dereven’kov IA, Makarov SV, Shpagilev NI, Salnikov DS, Koifman OI. Studies on reaction of glutathionylcobalamin with hypochlorite. Evidence of protective action of glutathionyl-ligand against corrin modification by hypochlorite. Biometals 2017; 30:757-764. [DOI: 10.1007/s10534-017-0044-8] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2017] [Accepted: 08/18/2017] [Indexed: 12/14/2022]
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6
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Hu Y, Xie G, Stanbury DM. Oxidations at Sulfur Centers by Aqueous Hypochlorous Acid and Hypochlorite: Cl + Versus O Atom Transfer. Inorg Chem 2017; 56:4047-4056. [PMID: 28290673 DOI: 10.1021/acs.inorgchem.6b03182] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
Sulfur-containing compounds are known to be susceptible to oxidation by aqueous HOCl, but the factors affecting the rates of these reactions are not well-established. Here we report on the kinetics of oxidation of thiosulfate, thiourea, thioglycolate, (methylthio)acetate, tetrathionate, dithiodiglycolate, and dithiodipropionate at 25 °C and 0.4 M ionic strength. These reactions obey the general rate law -d[OCl-]/dt = (kOCl-[OCl-] + kHOCl[HOCl])[substrate] with some exceptions: tetrathionate and the two disulfides undergo rate-limiting hydrolysis at high pH, and dithiodiglycolate has an additional term in the rate law that is second order in [substrate]. The reactions of HOCl are believed to have a Cl+ transfer mechanism, and in the case of thiosulfate the rate of hydrolysis of the ClS2O3- intermediate was determined. In the case of thiourea evidence was obtained for thiourea monoxide as a long-lived product. It is shown that sulfite and species with terminal sulfur atoms have kHOCl values in the vicinity of 1 × 109 M-1 s-1, while SCN- and thioethers react somewhat more slowly; tetrathionate, trithionate, and disulfides react much more slowly. Comparison of the rate constants with those for oxidation of these sulfur substrates by H2O2 and [Pt(CN)4Cl2]2- shows that HOCl reacts a few orders of magnitude more rapidly than [Pt(CN)4Cl2]2- and ∼9 orders of magnitude more rapidly than H2O2. Many of the kHOCl values are leveled by the high electrophilicity of HOCl. It is proposed that the kOCl- values correspond to oxygen-atom transfer mechanisms, as supported by LFERS (linear free energy relationships) relating these rate constants to those for reactions of H2O2 and [Pt(CN)4Cl2]2-.
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Affiliation(s)
- Ying Hu
- College of Chemical Engineering, China University of Mining and Technology , Xuzhou 221116, People's Republic of China.,Dept. of Chemistry and Biochemistry, Auburn University , Auburn, Alabama 36849, United States
| | - Guangyuan Xie
- College of Chemical Engineering, China University of Mining and Technology , Xuzhou 221116, People's Republic of China
| | - David M Stanbury
- Dept. of Chemistry and Biochemistry, Auburn University , Auburn, Alabama 36849, United States
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7
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Talib J, Maghzal GJ, Cheng D, Stocker R. Detailed protocol to assess in vivo and ex vivo myeloperoxidase activity in mouse models of vascular inflammation and disease using hydroethidine. Free Radic Biol Med 2016; 97:124-135. [PMID: 27184954 DOI: 10.1016/j.freeradbiomed.2016.05.004] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/05/2015] [Revised: 04/30/2016] [Accepted: 05/06/2016] [Indexed: 12/20/2022]
Abstract
Myeloperoxidase (MPO) activity contributes to arterial inflammation, vascular dysfunction and disease, including atherosclerosis. Current assessment of MPO activity in biological systems in vivo utilizes 3-chlorotyrosine (3-Cl-Tyr) as a biomarker of hypochlorous acid (HOCl) and other chlorinating species. However, 3-Cl-Tyr is formed in low yield and is subject to further metabolism. Recently, we reported a method to selectively assess MPO-activity in vivo by measuring the conversion of hydroethidine to 2-chloroethidium (2-Cl-E(+)) by liquid chromatography with tandem mass spectrometry (LC-MS/MS) (J. Biol. Chem., 289, 2014, pp. 5580-5595). The hydroethidine-based method has greater sensitivity for MPO activity than measurement of 3-Cl-Tyr. The current methods paper provides a detailed protocol to determine in vivo and ex vivo MPO activity in arteries from mouse models of vascular inflammation and disease by utilizing the conversion of hydroethidine to 2-Cl-E(+). Procedures for the synthesis of standards, preparation of tissue homogenates and the generation of 2-Cl-E(+) are also provided in detail, as are the conditions for LC-MS/MS detection of 2-Cl-E(+).
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Affiliation(s)
- Jihan Talib
- Vascular Biology Division, Victor Chang Cardiac Research Institute, Darlinghurst, New South Wales 2010, Australia
| | - Ghassan J Maghzal
- Vascular Biology Division, Victor Chang Cardiac Research Institute, Darlinghurst, New South Wales 2010, Australia
| | - David Cheng
- Vascular Biology Division, Victor Chang Cardiac Research Institute, Darlinghurst, New South Wales 2010, Australia
| | - Roland Stocker
- Vascular Biology Division, Victor Chang Cardiac Research Institute, Darlinghurst, New South Wales 2010, Australia; School of Medical Sciences, University of New South Wales, Sydney, Australia.
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8
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Szabó M, Baranyai Z, Somsák L, Fábián I. Decomposition of N-Chloroglycine in Alkaline Aqueous Solution: Kinetics and Mechanism. Chem Res Toxicol 2015; 28:1282-91. [PMID: 25849302 DOI: 10.1021/acs.chemrestox.5b00084] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Affiliation(s)
- Mária Szabó
- Department of Inorganic and Analytical Chemistry, and ‡Department of Organic Chemistry, University of Debrecen, Debrecen, Hungary
| | - Zsolt Baranyai
- Department of Inorganic and Analytical Chemistry, and ‡Department of Organic Chemistry, University of Debrecen, Debrecen, Hungary
| | - László Somsák
- Department of Inorganic and Analytical Chemistry, and ‡Department of Organic Chemistry, University of Debrecen, Debrecen, Hungary
| | - István Fábián
- Department of Inorganic and Analytical Chemistry, and ‡Department of Organic Chemistry, University of Debrecen, Debrecen, Hungary
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Galajda M, Fodor T, Purgel M, Fábián I. The kinetics and mechanism of the oxidation of pyruvate ion by hypochlorous acid. RSC Adv 2015. [DOI: 10.1039/c4ra12789g] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Kinetic experiments and DFT calculations confirm a concerted oxygen atom transfer mechanism for the oxidation of pyruvic acid by HOCl.
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Affiliation(s)
- Mónika Galajda
- MTA-DE Homogeneous Catalysis and Reaction Mechanisms Research Group
- Debrecen
- Hungary
| | - Tímea Fodor
- Department of Inorganic and Analytical Chemistry
- University of Debrecen
- Debrecen
- Hungary
| | - Mihály Purgel
- MTA-DE Homogeneous Catalysis and Reaction Mechanisms Research Group
- Debrecen
- Hungary
| | - István Fábián
- Department of Inorganic and Analytical Chemistry
- University of Debrecen
- Debrecen
- Hungary
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Nagy P. Kinetics and mechanisms of thiol-disulfide exchange covering direct substitution and thiol oxidation-mediated pathways. Antioxid Redox Signal 2013; 18:1623-41. [PMID: 23075118 PMCID: PMC3613173 DOI: 10.1089/ars.2012.4973] [Citation(s) in RCA: 273] [Impact Index Per Article: 24.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
SIGNIFICANCE Disulfides are important building blocks in the secondary and tertiary structures of proteins, serving as inter- and intra-subunit cross links. Disulfides are also the major products of thiol oxidation, a process that has primary roles in defense mechanisms against oxidative stress and in redox regulation of cell signaling. Although disulfides are relatively stable, their reduction, isomerisation, and interconversion as well as their production reactions are catalyzed by delicate enzyme machineries, providing a dynamic system in biology. Redox homeostasis, a thermodynamic parameter that determines which reactions can occur in cellular compartments, is also balanced by the thiol-disulfide pool. However, it is the kinetic properties of the reactions that best represent cell dynamics, because the partitioning of the possible reactions depends on kinetic parameters. CRITICAL ISSUES This review is focused on the kinetics and mechanisms of thiol-disulfide substitution and redox reactions. It summarizes the challenges and advances that are associated with kinetic investigations in small molecular and enzymatic systems from a rigorous chemical perspective using biological examples. The most important parameters that influence reaction rates are discussed in detail. RECENT ADVANCES AND FUTURE DIRECTIONS Kinetic studies of proteins are more challenging than small molecules, and quite often investigators are forced to sacrifice the rigor of the experimental approach to obtain the important kinetic and mechanistic information. However, recent technological advances allow a more comprehensive analysis of enzymatic systems via using the systematic kinetics apparatus that was developed for small molecule reactions, which is expected to provide further insight into the cell's machinery.
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Affiliation(s)
- Péter Nagy
- Department of Molecular Immunology and Toxicology, National Institute of Oncology, Budapest, Hungary.
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12
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Jacob C, Battaglia E, Burkholz T, Peng D, Bagrel D, Montenarh M. Control of oxidative posttranslational cysteine modifications: from intricate chemistry to widespread biological and medical applications. Chem Res Toxicol 2011; 25:588-604. [PMID: 22106817 DOI: 10.1021/tx200342b] [Citation(s) in RCA: 82] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
Cysteine residues in proteins and enzymes often fulfill rather important roles, particularly in the context of cellular signaling, protein-protein interactions, substrate and metal binding, and catalysis. At the same time, some of the most active cysteine residues are also quite sensitive toward (oxidative) modification. S-Thiolation, S-nitrosation, and disulfide bond and sulfenic acid formation are processes which occur frequently inside the cell and regulate the function and activity of many proteins and enzymes. During oxidative stress, such modifications trigger, among others, antioxidant responses and cell death. The unique combination of nonredox function on the one hand and participation in redox signaling and control on the other has placed many cysteine proteins at the center of drug design and pesticide development. Research during the past decade has identified a range of chemically rather interesting, biologically very active substances that are able to modify cysteine residues in such proteins with huge efficiency, yet also considerable selectivity. These agents are often based on natural products and range from simple disulfides to complex polysulfanes, tetrahydrothienopyridines, α,β -unsaturated disulfides, thiuramdisulfides, and 1,2-dithiole-3-thiones. At the same time, inhibition of enzymes responsible for posttranslational cysteine modifications (and their removal) has become an important area of innovative drug research. Such investigations into the control of the cellular thiolstat by thiol-selective agents cross many disciplines and are often far from trivial.
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Affiliation(s)
- Claus Jacob
- Division of Bioorganic Chemistry, School of Pharmacy, Saarland University, D-66123 Saarbruecken, Germany.
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Nagy P, Winterbourn CC. Rapid reaction of hydrogen sulfide with the neutrophil oxidant hypochlorous acid to generate polysulfides. Chem Res Toxicol 2010; 23:1541-3. [PMID: 20845929 DOI: 10.1021/tx100266a] [Citation(s) in RCA: 151] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
H₂S has been recognized as a signaling molecule and mediator of inflammation. Here, we report the kinetics and mechanism of its reaction with the neutrophil oxidant hypochlorous acid. Stopped flow studies, carried out at high pH, showed this reaction to be extremely fast, with a second-order rate constant extrapolated to be 2 × 10⁹ M⁻¹ s⁻¹ at pH 7.4. The reaction produces polysulfides rather than polythionates and may represent a novel pathway for protein Cys-sulfhydration, a recently proposed mechanism for H₂S signaling.
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Affiliation(s)
- Péter Nagy
- Department of Pathology, University of Otago Christchurch, P.O. Box 4345, Christchurch, New Zealand.
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Ueki H, Chapman G, Ashby MT. Reactive sulfur species: kinetics and mechanism of the oxidation of aryl sulfinates with hypochlorous acid. J Phys Chem A 2010; 114:1670-6. [PMID: 20039719 DOI: 10.1021/jp906651n] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The mechanism of oxidation of ArSO(2)(-) (PhSO(2)(-) and 5-sulfinato-2-nitrobenzoic acid = TNBO(2)(1-/2-)) with HOCl/OCl(-) has been investigated using the kinetic method. In contrast to previous reports for PhSO(2)(-) (for which it was suggested that OCl(-) and not HOCl was the reactant), the reaction proceeds through a conventional pathway: nucleophilic attack by ArSO(2)(-) on HOCl with concomitant Cl(+) transfer to give a sulfonyl chloride intermediate (ArSO(2)Cl), which we have identified spectrophotometrically. Remarkably, the rate constant for the reaction of HOCl with ArSO(2)(-) is on the order of 10(9) M(-1) s(-1), larger than the rate constants for corresponding thiolates, and is nearly diffusion-controlled. In contrast, the rate constant for the reaction of OCl(-) with ArSO(2)(-) is approximately 7 orders of magnitude smaller.
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Affiliation(s)
- Hisanori Ueki
- Department of Chemistry and Biochemistry, University of Oklahoma, Norman, Oklahoma 73019, USA
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Gomez-Mejiba SE, Zhai Z, Gimenez MS, Ashby MT, Chilakapati J, Kitchin K, Mason RP, Ramirez DC. Myeloperoxidase-induced genomic DNA-centered radicals. J Biol Chem 2010; 285:20062-71. [PMID: 20406811 DOI: 10.1074/jbc.m109.086579] [Citation(s) in RCA: 67] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
Myeloperoxidase (MPO) released by activated neutrophils can initiate and promote carcinogenesis. MPO produces hypochlorous acid (HOCl) that oxidizes the genomic DNA in inflammatory cells as well as in surrounding epithelial cells. DNA-centered radicals are early intermediates formed during DNA oxidation. Once formed, DNA-centered radicals decay by mechanisms that are not completely understood, producing a number of oxidation products that are studied as markers of DNA oxidation. In this study we employed the 5,5-dimethyl-1-pyrroline N-oxide-based immuno-spin trapping technique to investigate the MPO-triggered formation of DNA-centered radicals in inflammatory and epithelial cells and to test whether resveratrol blocks HOCl-induced DNA-centered radical formation in these cells. We found that HOCl added exogenously or generated intracellularly by MPO that has been taken up by the cell or by MPO newly synthesized produces DNA-centered radicals inside cells. We also found that resveratrol passed across cell membranes and scavenged HOCl before it reacted with the genomic DNA, thus blocking DNA-centered radical formation. Taken together our results indicate that the formation of DNA-centered radicals by intracellular MPO may be a useful point of therapeutic intervention in inflammation-induced carcinogenesis.
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Affiliation(s)
- Sandra E Gomez-Mejiba
- Experimental Therapeutics Research Program, Oklahoma Medical Research Foundation, Oklahoma City, Oklahoma 73104, USA.
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Xulu BA, Ashby MT. Small molecular, macromolecular, and cellular chloramines react with thiocyanate to give the human defense factor hypothiocyanite. Biochemistry 2010; 49:2068-74. [PMID: 20085320 PMCID: PMC2831154 DOI: 10.1021/bi902089w] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Thiocyanate reacts noncatalytically with myeloperoxidase-derived HOCl to produce hypothiocyanite (OSCN(-)), thereby potentially limiting the propensity of HOCl to inflict host tissue damage that can lead to inflammatory diseases. However, the efficiency with which SCN(-) captures HOCl in vivo depends on the concentration of SCN(-) relative to other chemical targets. In blood plasma, where the concentration of SCN(-) is relatively low, proteins may be the principal initial targets of HOCl, and chloramines are a significant product. Chloramines eventually decompose to irreversibly damage proteins. In the present study, we demonstrate that SCN(-) reacts efficiently with chloramines in small molecules, in proteins, and in Escherichia coli cells to give OSCN(-) and the parent amine. Remarkably, OSCN(-) reacts faster than SCN(-) with chloramines. These reactions of SCN(-) and OSCN(-) with chloramines may repair some of the damage that is inflicted on protein amines by HOCl. Our observations are further evidence for the importance of secondary reactions during the redox cascades that are associated with oxidative stress by hypohalous acids.
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Affiliation(s)
- Bheki A. Xulu
- Department of Chemistry and Biochemistry, University of Oklahoma, Norman, OK 73019
| | - Michael T. Ashby
- Department of Chemistry and Biochemistry, University of Oklahoma, Norman, OK 73019
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Nagy P, Winterbourn CC. Redox Chemistry of Biological Thiols. ADVANCES IN MOLECULAR TOXICOLOGY 2010. [DOI: 10.1016/s1872-0854(10)04006-3] [Citation(s) in RCA: 86] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/03/2022]
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Yuan W, Wang Y, Heinecke JW, Fu X. Hypochlorous acid converts the gamma-glutamyl group of glutathione disulfide to 5-hydroxybutyrolactam, a potential marker for neutrophil activation. J Biol Chem 2009; 284:26908-17. [PMID: 19584048 DOI: 10.1074/jbc.m109.005496] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
In healthy cells, glutathione disulfide (GSSG) is rapidly reduced back to glutathione (GSH) by glutathione reductase to maintain redox status. The ratio of GSH/GSSG has been used as an indicator of oxidative stress. However, hypochlorous acid (HOCl) generated by the myeloperoxidase-H(2)O(2)-Cl(-) system of neutrophils converts GSH to irreversible oxidation products. Although several such products have been identified, yields of these compounds are very low in biological systems, and they cannot account quantitatively for thiol loss. In the current studies, we use liquid chromatography-mass spectrometry (LC-MS) to demonstrate that HOCl and chloramines oxidize GSSG to two irreversible products in high yield. The products, termed M-45 and M-90, are, respectively, 45 or 90 atomic mass units lighter than GSSG. The reaction pathway involves chloramine and aldehyde intermediates, and converts the gamma-glutamyl residues of GSSG to 5-hydroxybutyrolactam. Importantly, M-45 and M-90 were resistant to reduction by glutathione reductase. Moreover, the monohydroxylbutyrolactam M-45 accounted for >90% of the endogenous GSH oxidation products generated by activated neutrophils. Because the reaction pathway involves chlorinating intermediates, hydroxylbutyrolactams are likely to be specific products of HOCl, which is generated only by myeloperoxidase. Therefore, our observations implicate M-45 as a potential biomarker for myeloperoxidase activity in vivo.
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Affiliation(s)
- Wei Yuan
- Department of Medicine, University of Washington, Seattle, Washington 98195, USA
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Davies MJ, Hawkins CL, Pattison DI, Rees MD. Mammalian heme peroxidases: from molecular mechanisms to health implications. Antioxid Redox Signal 2008; 10:1199-234. [PMID: 18331199 DOI: 10.1089/ars.2007.1927] [Citation(s) in RCA: 423] [Impact Index Per Article: 26.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
A marked increase in interest has occurred over the last few years in the role that mammalian heme peroxidase enzymes, primarily myeloperoxidase, eosinophil peroxidase, and lactoperoxidase, may play in both disease prevention and human pathologies. This increased interest has been sparked by developments in our understanding of polymorphisms that control the levels of these enzymes, a greater understanding of the basic chemistry and biochemistry of the oxidants formed by these species, the development of specific biomarkers that can be used in vivo to detect damage induced by these oxidants, the detection of active forms of these peroxidases at most, if not all, sites of inflammation, and a correlation between the levels of these enzymes and a number of major human pathologies. This article reviews recent developments in our understanding of the enzymology, chemistry, biochemistry and biologic roles of mammalian peroxidases and the oxidants that they generate, the potential role of these oxidants in human disease, and the use of the levels of these enzymes in disease prognosis.
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Affiliation(s)
- Michael J Davies
- The Heart Research Institute, Camperdown, University of Sydney, Sydney, Australia., Faculty of Medicine, University of Sydney, Sydney, Australia.
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20
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Harwood DT, Nimmo SL, Kettle AJ, Winterbourn CC, Ashby MT. Molecular Structure and Dynamic Properties of a Sulfonamide Derivative of Glutathione That Is Produced Under Conditions of Oxidative Stress by Hypochlorous Acid. Chem Res Toxicol 2008; 21:1011-6. [DOI: 10.1021/tx800050n] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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