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Therapeutic role of nitric oxide as emerging molecule. Biomed Pharmacother 2017; 85:182-201. [DOI: 10.1016/j.biopha.2016.11.125] [Citation(s) in RCA: 61] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2016] [Revised: 11/10/2016] [Accepted: 11/27/2016] [Indexed: 01/21/2023] Open
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Koppaka V, Thompson DC, Chen Y, Ellermann M, Nicolaou KC, Juvonen RO, Petersen D, Deitrich RA, Hurley TD, Vasiliou V. Aldehyde dehydrogenase inhibitors: a comprehensive review of the pharmacology, mechanism of action, substrate specificity, and clinical application. Pharmacol Rev 2012; 64:520-39. [PMID: 22544865 PMCID: PMC3400832 DOI: 10.1124/pr.111.005538] [Citation(s) in RCA: 396] [Impact Index Per Article: 33.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Aldehyde dehydrogenases (ALDHs) belong to a superfamily of enzymes that play a key role in the metabolism of aldehydes of both endogenous and exogenous derivation. The human ALDH superfamily comprises 19 isozymes that possess important physiological and toxicological functions. The ALDH1A subfamily plays a pivotal role in embryogenesis and development by mediating retinoic acid signaling. ALDH2, as a key enzyme that oxidizes acetaldehyde, is crucial for alcohol metabolism. ALDH1A1 and ALDH3A1 are lens and corneal crystallins, which are essential elements of the cellular defense mechanism against ultraviolet radiation-induced damage in ocular tissues. Many ALDH isozymes are important in oxidizing reactive aldehydes derived from lipid peroxidation and thereby help maintain cellular homeostasis. Increased expression and activity of ALDH isozymes have been reported in various human cancers and are associated with cancer relapse. As a direct consequence of their significant physiological and toxicological roles, inhibitors of the ALDH enzymes have been developed to treat human diseases. This review summarizes known ALDH inhibitors, their mechanisms of action, isozyme selectivity, potency, and clinical uses. The purpose of this review is to 1) establish the current status of pharmacological inhibition of the ALDHs, 2) provide a rationale for the continued development of ALDH isozyme-selective inhibitors, and 3) identify the challenges and potential therapeutic rewards associated with the creation of such agents.
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Affiliation(s)
- Vindhya Koppaka
- Department of Pharmaceutical Sciences, University of Colorado Denver, 12850 East Montview Blvd., Aurora, CO 80045, USA
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Sutton AD, Williamson M, Weismiller H, Toscano JP. Optimization of HNO production from N,O-bis-acylated hydroxylamine derivatives. Org Lett 2011; 14:472-5. [PMID: 22196028 DOI: 10.1021/ol203016c] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
A wide range of N,O-bis-acylated hydroxylamine derivatives with chloro or arenesulfonyl leaving groups, and a related set of N-hydroxy-N-acylsulfonamides, have been synthesized and evaluated for nitroxyl (HNO) production. Mechanistic studies have revealed that the observed aqueous chemistry is more complicated than originally anticipated, and have been used to develop a new series of efficient HNO precursors (4u-4x, 7c-7d) with tunable half-lives.
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Affiliation(s)
- Art D Sutton
- Department of Chemistry, Johns Hopkins University, Baltimore, Maryland 21218, USA
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Doctorovich F, Bikiel D, Pellegrino J, Suárez SA, Larsen A, Martí MA. Nitroxyl (azanone) trapping by metalloporphyrins. Coord Chem Rev 2011. [DOI: 10.1016/j.ccr.2011.04.012] [Citation(s) in RCA: 76] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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Flores-Santana W, Salmon DJ, Donzelli S, Switzer CH, Basudhar D, Ridnour L, Cheng R, Glynn SA, Paolocci N, Fukuto JM, Miranda KM, Wink DA. The specificity of nitroxyl chemistry is unique among nitrogen oxides in biological systems. Antioxid Redox Signal 2011; 14:1659-74. [PMID: 21235346 PMCID: PMC3070000 DOI: 10.1089/ars.2010.3841] [Citation(s) in RCA: 77] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
The importance of nitric oxide in mammalian physiology has been known for nearly 30 years. Similar attention for other nitrogen oxides such as nitroxyl (HNO) has been more recent. While there has been speculation as to the biosynthesis of HNO, its pharmacological benefits have been demonstrated in several pathophysiological settings such as cardiovascular disorders, cancer, and alcoholism. The chemical biology of HNO has been identified as related to, but unique from, that of its redox congener nitric oxide. A summary of these findings as well as a discussion of possible endogenous sources of HNO is presented in this review.
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Affiliation(s)
- Wilmarie Flores-Santana
- Radiation Biology Branch, National Cancer Institute, National Institutes of Health, Bethesda, Maryland 20892, USA
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Huang Z, Knaus EE. O2-(N-Hydroxy(methoxy)-2-ethanesulfonamido) Protected Diazen-1-ium-1,2-diolates: Nitric Oxide Release via a Base-Induced β-Elimination Cleavage. Org Lett 2011; 13:1178-81. [DOI: 10.1021/ol200053z] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Zhangjian Huang
- Faculty of Pharmacy and Pharmaceutical Sciences, University of Alberta, Edmonton, Alberta, T6G 2N8, Canada
| | - Edward E. Knaus
- Faculty of Pharmacy and Pharmaceutical Sciences, University of Alberta, Edmonton, Alberta, T6G 2N8, Canada
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Andrei D, Salmon DJ, Donzelli S, Wahab A, Klose JR, Citro ML, Saavedra JE, Wink DA, Miranda KM, Keefer LK. Dual mechanisms of HNO generation by a nitroxyl prodrug of the diazeniumdiolate (NONOate) class. J Am Chem Soc 2010; 132:16526-32. [PMID: 21033665 PMCID: PMC2984372 DOI: 10.1021/ja106552p] [Citation(s) in RCA: 49] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2010] [Indexed: 12/28/2022]
Abstract
Here we describe a novel caged form of the highly reactive bioeffector molecule, nitroxyl (HNO). Reacting the labile nitric oxide (NO)- and HNO-generating salt of structure iPrHN-N(O)═NO(-)Na(+) (1, IPA/NO) with BrCH(2)OAc produced a stable derivative of structure iPrHN-N(O)═NO-CH(2)OAc (2, AcOM-IPA/NO), which hydrolyzed an order of magnitude more slowly than 1 at pH 7.4 and 37 °C. Hydrolysis of 2 to generate HNO proceeded by at least two mechanisms. In the presence of esterase, straightforward dissociation to acetate, formaldehyde, and 1 was the dominant path. In the absence of enzyme, free 1 was not observed as an intermediate and the ratio of NO to HNO among the products approached zero. To account for this surprising result, we propose a mechanism in which base-induced removal of the N-H proton of 2 leads to acetyl group migration from oxygen to the neighboring nitrogen, followed by cleavage of the resulting rearrangement product to isopropanediazoate ion and the known HNO precursor, CH(3)-C(O)-NO. The trappable yield of HNO from 2 was significantly enhanced over 1 at physiological pH, in part because the slower rate of hydrolysis for 2 generated a correspondingly lower steady-state concentration of HNO, thus, minimizing self-consumption and enhancing trapping by biological targets such as metmyoglobin and glutathione. Consistent with the chemical trapping efficiency data, micromolar concentrations of prodrug 2 displayed significantly more potent sarcomere shortening effects relative to 1 on ventricular myocytes isolated from wild-type mouse hearts, suggesting that 2 may be a promising lead compound for the development of heart failure therapies.
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Kumar MR, Fukuto JM, Miranda KM, Farmer PJ. Reactions of HNO with heme proteins: new routes to HNO-heme complexes and insight into physiological effects. Inorg Chem 2010; 49:6283-92. [PMID: 20666387 DOI: 10.1021/ic902319d] [Citation(s) in RCA: 56] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The formation and interconversion of nitrogen oxides has been of interest in numerous contexts for decades. Early studies focused on gas-phase reactions, particularly with regard to industrial and atmospheric environments, and on nitrogen fixation. Additionally, investigation of the coordination chemistry of nitric oxide (NO) with hemoglobin dates back nearly a century. With the discovery in the early 1980s that NO is biosynthesized as a molecular signaling agent, the literature has been focused on the biological effects of nitrogen oxides, but the original concerns remain relevant. For instance, hemoglobin has long been known to react with nitrite, but this reductase activity has recently been considered to be important to produce NO under hypoxic conditions. The association of nitrosyl hydride (HNO; also commonly referred to as nitroxyl) with heme proteins can also produce NO by reductive nitrosylation. Furthermore, HNO is considered to be an intermediate in bacterial denitrification, but conclusive identification has been elusive. The authors of this article have approached the bioinorganic chemistry of HNO from different perspectives, which have converged because heme proteins are important biological targets of HNO.
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Affiliation(s)
- Murugaeson R Kumar
- Department of Chemistry and Biochemistry, Baylor University, Waco, Texas 76706, USA
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Huang Z, Velázquez C, Abdellatif K, Chowdhury M, Jain S, Reisz J, Dumond J, King SB, Knaus E. Acyclic triaryl olefins possessing a sulfohydroxamic acid pharmacophore: synthesis, nitric oxide/nitroxyl release, cyclooxygenase inhibition, and anti-inflammatory studies. Org Biomol Chem 2010; 8:4124-30. [PMID: 20664853 DOI: 10.1039/c005066k] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Nitric oxide (NO) and its reduced form nitroxyl (HNO), effective vasodilation agents that can inhibit platelet aggregation and adhesion, could suppress adverse cardiovascular effects associated with the use of selective COX-2 inhibitors. In this regard, a sulfohydroxamic acid (SO(2)NHOH) substituent, that can act as a dual NO/HNO donor moiety, was inserted at the para-position of the C2 phenyl ring of acyclic 2-alkyl-1,1,2-triaryl olefins previously shown to be potent and highly selective COX-2 inhibitors. Although this new group of 1,1-diaryl-2-(4-hydroxyaminosulfonylphenyl)alk-1-enes exhibited weak inhibition of the constitutive cyclooxygenase-1 (COX-1) and inducible COX-2 isozymes, in vivo studies showed anti-inflammatory potencies that were generally intermediate between that of the reference drugs aspirin and ibuprofen. All compounds released NO (5.6-13.5% range) upon incubation with phosphate buffer which was increased further (8.3-25.6% range) in the presence of the oxidant K(3)(FeCN(6)).The low release of HNO in MeOH-buffer (< 2% at 24 h incubation) was much higher at alkaline pH (11-37% range). The concept of designing better anti-inflammatory drugs possessing either an effective HNO, or dual NO/HNO, donor moiety that are devoid of adverse ulcerogenic and/or cardiovascular side effects warrants further investigation.
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Affiliation(s)
- Zhangjian Huang
- Faculty of Pharmacy and Pharmaceutical Sciences, University of Alberta, Edmonton, Alberta, CanadaT6G 2N8
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Sanchez-Cruz P, Alegría AE. Quinone-enhanced reduction of nitric oxide by xanthine/xanthine oxidase. Chem Res Toxicol 2009; 22:818-23. [PMID: 19301825 DOI: 10.1021/tx800392j] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
The quinones 1,4-naphthoquinone, methyl-1,4-naphthoquinone, tetramethyl-1,4-benzoquinone, 2,3-dimethoxy-5-methyl-1,4-benzoquinone, 2,6-dimethylbenzoquinone, 2,6-dimethoxybenzoquinone, and 9,10-phenanthraquinone enhance the rate of nitric oxide reduction by xanthine/xanthine oxidase in nitrogen-saturated phosphate buffer (pH 7.4). Maximum initial rates of NO reduction (V(max)) and the amount of nitrous oxide produced after 5 min of reaction increase with quinone one- and two-electron redox potentials measured in acetonitrile. One of the most active quinones of those studied is 9,10-phenanthraquinone with a V(max) value 10 times larger than that corresponding to the absence of quinone, under the conditions of this work. Because NO production is enhanced under hypoxia and under certain pathological conditions, the observations obtained in this work are very relevant to such conditions.
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Affiliation(s)
- Pedro Sanchez-Cruz
- Department of Chemistry, University of Puerto Rico at Humacao, Humacao, Puerto Rico 00791
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Switzer CH, Flores-Santana W, Mancardi D, Donzelli S, Basudhar D, Ridnour LA, Miranda KM, Fukuto JM, Paolocci N, Wink DA. The emergence of nitroxyl (HNO) as a pharmacological agent. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 2009; 1787:835-40. [PMID: 19426703 DOI: 10.1016/j.bbabio.2009.04.015] [Citation(s) in RCA: 103] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/30/2008] [Revised: 04/28/2009] [Accepted: 04/29/2009] [Indexed: 11/15/2022]
Abstract
Once a virtually unknown nitrogen oxide, nitroxyl (HNO) has emerged as a potential pharmacological agent. Recent advances in the understanding of the chemistry of HNO has led to the an understanding of HNO biochemistry which is vastly different from the known chemistry and biochemistry of nitric oxide (NO), the one-electron oxidation product of HNO. The cardiovascular roles of NO have been extensively studied, as NO is a key modulator of vascular tone and is involved in a number of vascular related pathologies. HNO displays unique cardiovascular properties and has been shown to have positive lusitropic and ionotropic effects in failing hearts without a chronotropic effect. Additionally, HNO causes a release of CGRP and modulates calcium channels such as ryanodine receptors. HNO has shown beneficial effects in ischemia reperfusion injury, as HNO treatment before ischemia-reperfusion reduces infarct size. In addition to the cardiovascular effects observed, HNO has shown initial promise in the realm of cancer therapy. HNO has been demonstrated to inhibit GAPDH, a key glycolytic enzyme. Due to the Warburg effect, inhibiting glycolysis is an attractive target for inhibiting tumor proliferation. Indeed, HNO has recently been shown to inhibit tumor proliferation in mouse xenografts. Additionally, HNO inhibits tumor angiogenesis and induces cancer cell apoptosis. The effects seen with HNO donors are quite different from NO donors and in some cases are opposite. The chemical nature of HNO explains how HNO and NO, although closely chemically related, act so differently in biochemical systems. This also gives insight into the potential molecular motifs that may be reactive towards HNO and opens up a novel field of pharmacological development.
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Affiliation(s)
- Christopher H Switzer
- Radiation Biology Branch, National Cancer Institute, National Institutes of Health, Building 10, Room B3-B35, Bethesda, MD 20892, USA
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Fukuto JM, Switzer CH, Miranda KM, Wink DA. NITROXYL (HNO): Chemistry, Biochemistry, and Pharmacology. Annu Rev Pharmacol Toxicol 2005; 45:335-55. [PMID: 15822180 DOI: 10.1146/annurev.pharmtox.45.120403.095959] [Citation(s) in RCA: 103] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Recent discoveries of novel and potentially important biological activity have spurred interest in the chemistry and biochemistry of nitroxyl (HNO). It has become clear that, among all the nitrogen oxides, HNO is unique in its chemistry and biology. Currently, the intimate chemical details of the biological actions of HNO are not well understood. Moreover, many of the previously accepted chemical properties of HNO have been recently revised, thus requiring reevaluation of possible mechanisms of biological action. Herein, we review these developments in HNO chemistry and biology.
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Affiliation(s)
- Jon M Fukuto
- Interdepartmental Program in Molecular Toxicology, UCLA School of Public Health, Los Angeles, California 90095-1772, USA.
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Pennington RL, Sha X, King SB. N-Hydroxy sulfonimidamides as new nitroxyl (HNO) donors. Bioorg Med Chem Lett 2005; 15:2331-4. [PMID: 15837319 DOI: 10.1016/j.bmcl.2005.02.082] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2005] [Revised: 02/24/2005] [Accepted: 02/28/2005] [Indexed: 11/16/2022]
Abstract
Chlorination and condensation of simple sulfinamides with O-benzyl and O-tert-butyl dimethyl siloxy hydroxylamine gives O-protected N-hydroxy sulfonimidamides. Deprotection of these compounds produces the corresponding sulfinamide and nitrous oxide, which provides evidence for the intermediacy of nitroxyl (HNO) and identifies these compounds as new potential HNO donors.
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Affiliation(s)
- Richard L Pennington
- Department of Chemistry, College of St. Mary, 1901 S. 72nd Street, Omaha, NE 68124-2377, USA
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Zeng BB, Huang J, Wright MW, King SB. Nitroxyl (HNO) release from new functionalized N-hydroxyurea-derived acyl nitroso-9,10-dimethylanthracene cycloadducts. Bioorg Med Chem Lett 2005; 14:5565-8. [PMID: 15482925 DOI: 10.1016/j.bmcl.2004.08.062] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2004] [Revised: 08/20/2004] [Accepted: 08/27/2004] [Indexed: 10/26/2022]
Abstract
A thermal retro-Diels-Alder decomposition of N-hydroxyurea-derived acyl nitroso compounds and 9,10-dimethylanthracene cycloadducts followed by acyl nitroso compound hydrolysis produces nitrous oxide, evidence for the formation of nitroxyl, the one-electron reduced form of nitric oxide that has drawn considerable attention for its potential roles in biological systems. EPR and NMR spectroscopy provide further evidence for nitroxyl formation and kinetic information, respectively. Such compounds may prove to be useful alternative nitroxyl donors.
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Affiliation(s)
- Bu-Bing Zeng
- Department of Chemistry, Wake Forest University, Salem Hall, Winston-Salem, NC 27109, USA
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Alegria AE, Sanchez S, Quintana I. Quinone-enhanced ascorbate reduction of nitric oxide: role of quinone redox potential. Free Radic Res 2005; 38:1107-12. [PMID: 15512799 DOI: 10.1080/10715760400009852] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
The quinones 1,4-naphthoquinone (NQ), methyl-1,4-naphthoquinone (MNQ), trimethyl-1,4-benzoquinone (TMQ) and 2,3-dimethoxy-5-methyl-1,4-benzoquinone (UQ-0) enhance the rate of nitric oxide (NO) reduction by ascorbate in nitrogen-saturated phosphate buffer (pH 7.4). The observed rate constants for this reaction were determined to be 16+/-2,215+/-6,290+/-14 and 462+/-18 M-1 s-1, for MNQ, TMQ, NQ and UQ-0, respectively. These rate constants increase with an increase in quinone one-electron redox potential at neutral pH, E1(7). Since NO production is enhanced under hypoxia and under certain pathological conditions, the observations obtained in this work are very relevant to such conditions.
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Affiliation(s)
- Antonio E Alegria
- Department of Chemistry, University of Puerto Rico at Humacao, CUH Station, Humacao, PR 00791.
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Arulsamy N, Bohle DS. Multiplicity control in the polygeminal diazeniumdiolation of active hydrogen bearing carbons: chemistry of a new type of trianionic molecular propeller. J Am Chem Soc 2001; 123:10860-9. [PMID: 11686687 DOI: 10.1021/ja002634b] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Over a century ago, Traube reported the reaction of four nitric oxides with acetone and sodium ethoxide to yield sodium methanebis(diazene-N-oxide-N'-hydroxylate) and sodium acetate. However, when this reaction is carried out in the presence of nitric oxide at slightly elevated pressures (35-40 psi), a product corresponding to the addition of six nitric oxides, sodium methanetris(diazene-N-oxide-N'-hydroxylate), forms as the main product in addition to a trace of the previously observed sodium methanebis(diazene-N-oxide-N'-hydroxylate) and sodium acetate. The corresponding potassium salts form when potassium hydroxide is employed as the base, while lithium hydroxide results in the formation of lithium methanebis(diazene-N-oxide-N'-hydroxylate) exclusively. Nitric oxide reacts with 3,3-dimethylbutan-2-one in the presence of sodium and potassium hydroxide in methanol to yield sodium and potassium 3,3-dimethylbutan-2-one-1,1,1-tris(diazene-N-oxide-N'-hydroxylate), respectively. In contrast, the reaction in the presence of lithium hydroxide forms lithium methanebis(diazene-N-oxide-N'-hydroxylate) and lithium pivalate. The differential reactivity of nitric oxide with acetone and 3,3-dimethylbutan-2-one in the presence of the three bases is attributed to competing hydrolytic reactions of the acetyl and trimethylacetyl group-containing intermediates. A mechanism is proposed for the nitric oxide addition to active methyl groups in these reactions, where the product distribution between the di- and trisubstituted methanes is under kinetic control of the competing reactions. The products are characterized by NMR and IR spectroscopy, differential scanning calorimetry, and elemental analysis. Two differentially hydrated forms of potassium methanetris(diazene-N-oxide-N'-hydroxylate) are characterized by single-crystal X-ray diffraction. From the metathesis reaction of the silver salt of methanetris(diazene-N-oxide-N'-hydroxylate) with ammonium iodide, the corresponding ammonium salt is isolated in 59% yield, but only trace amounts of methylated products form in the reaction of the silver salt with methyl iodide. Density functional calculations (B3LYP/6-311++G) are used to evaluate the bonding, ground-state structures, and energy landscape for the different conformers of methanetris(diazene-N-oxide-N'-hydroxylate)(3-) trianion, a new type of a molecular propeller, and its corresponding triprotonated acid.
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Affiliation(s)
- N Arulsamy
- Department of Chemistry, University of Wyoming, Laramie, WY 82071-3838, USA
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Nelli S, McIntosh L, Martin W. Role of copper ions and cytochrome P450 in the vasodilator actions of the nitroxyl anion generator, Angeli's salt, on rat aorta. Eur J Pharmacol 2001; 412:281-9. [PMID: 11166292 DOI: 10.1016/s0014-2999(00)00845-1] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Since copper ions catalyse the oxidation of nitroxyl anion to nitric oxide, we investigated whether this might explain the vasodilator actions of the nitroxyl generator, Angeli's salt, in rat aorta. Parallel studies were conducted with S-nitroso-N-acetyl-D,L-penicillamine (SNAP), since Cu ions catalyse the liberation of nitric oxide from this compound. Copper sulphate enhanced relaxation to Angeli's salt and SNAP but this resulted from reduced destruction of nitric oxide by superoxide rather than from enhanced generation of nitric oxide, since it was mimicked by superoxide dismutase and by the superoxide dismutase mimetic, MnCl2. Results with the selective Cu2+ chelators, neocuproine and bathocuproine disulfonate, and the Cu2+ chelators, EDTA, cuprizone and diethyldithiocarbamate, confirmed an important role for endogenous copper in mediating relaxation to SNAP but suggested only a minor role for Angeli's salt. Relaxation to Angeli's salt was, however, powerfully blocked by proadifen, suggesting an important role for cytochrome P450.
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Affiliation(s)
- S Nelli
- Division of Neuroscience and Biomedical Systems, Institute of Biomedical and Life Sciences, West Medical Building, University of Glasgow, G12 8QQ, Scotland, Glasgow, UK
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Nelli S, Hillen M, Buyukafsar K, Martin W. Oxidation of nitroxyl anion to nitric oxide by copper ions. Br J Pharmacol 2000; 131:356-62. [PMID: 10991931 PMCID: PMC1572311 DOI: 10.1038/sj.bjp.0703550] [Citation(s) in RCA: 40] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022] Open
Abstract
1. This study made use of a nitric oxide-sensitive electrode to examine possible means of generating nitric oxide from nitroxyl anion (NO(-)) released upon the decomposition of Angeli's salt. 2. Our results show that copper ions (from CuSO(4)) catalyze the rapid and efficient oxidation of nitroxyl to nitric oxide. Indeed, the concentrations of copper required to do so (0.1 - 100 microM) are roughly 100-times lower than those required to generate equivalent amounts of nitric oxide from S-nitroso-N-acetyl-D,L-penicillamine (SNAP). 3. Experiments with ascorbate (1 mM), which reduces Cu(2+) ions to Cu(+), and with the Cu(2+) chelators, EDTA and cuprizone, and the Cu(+) chelator, neocuproine, each at 1 mM, suggest that the oxidation is catalyzed by copper ions in both valency states. 4. Some compounds containing other transition metals, i.e. methaemoglobin, ferricytochrome c and Mn(III)TMPyP, were much less efficient than CuSO(4) in catalyzing the formation of nitric oxide from nitroxyl, while FeSO(4), FeCl(3), MnCl(2), and ZnSO(4) were inactive. 5. Of the copper containing enzymes examined, Cu-Zn superoxide dismutase and ceruloplasmin were weak generators of nitric oxide from nitroxyl, even at concentrations (2500 and 30 u ml(-1), respectively) vastly greater than are present endogenously. Two others, ascorbate oxidase (10 u ml(-1)) and tyrosinase (250 u ml(-1)) were inactive. 6. Our findings suggest that a copper-containing enzyme may be responsible for the rapid oxidation of nitroxyl to nitric oxide by cells, but the identity of such an enzyme remains elusive.
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Affiliation(s)
- Silvia Nelli
- Division of Neuroscience & Biomedical Systems, Institute of Biomedical & Life Sciences, West Medical Building, University of Glasgow, Glasgow G12 8QQ, Scotland
| | - Mark Hillen
- Division of Neuroscience & Biomedical Systems, Institute of Biomedical & Life Sciences, West Medical Building, University of Glasgow, Glasgow G12 8QQ, Scotland
| | - Kansu Buyukafsar
- Division of Neuroscience & Biomedical Systems, Institute of Biomedical & Life Sciences, West Medical Building, University of Glasgow, Glasgow G12 8QQ, Scotland
| | - William Martin
- Division of Neuroscience & Biomedical Systems, Institute of Biomedical & Life Sciences, West Medical Building, University of Glasgow, Glasgow G12 8QQ, Scotland
- Author for correspondence:
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Booth BP, Tabrizi-Fard MA, Fung H. Calcitonin gene-related peptide-dependent vascular relaxation of rat aorta. An additional mechanism for nitroglycerin. Biochem Pharmacol 2000; 59:1603-9. [PMID: 10799659 DOI: 10.1016/s0006-2952(00)00290-2] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
We investigated the involvement of calcitonin gene-related peptide (CGRP) in the vasodilatory mechanism of action of nitric oxide (NO) donors. The functional role of CGRP in NO donor-induced vasodilation of isolated rat aortic rings was determined by incubating these drugs with and without CGRP(8-37), a selective CGRP receptor antagonist. CGRP(8-37) (0.63 microM) induced rightward shifts in the vasodilatory concentration-response curves for nitroglycerin (NTG), Piloty's acid (PA), and SIN-1 (linsidomine). The EC(50) values for NTG, PA, and SIN-1 were increased by 8.3-, 5.2-, and 2.3-fold, respectively (P < 0.05). The release of CGRP from rat aorta in response to NTG and PA was measured specifically by radioimmunoassay. Thirty-minute incubations of NTG or PA with rat aorta induced 189.5 and 214.6% increases, respectively, in CGRP release when compared with the control (P < 0.05). The concentration-response curves of sodium nitroprusside (SNP), S-nitroso-acetylpenicillamine (SNAP), tetranitromethane (TNM), diethylamine NO complex (DEA-NO), and diethylenetriamine/nitric oxide adduct (DETA NONOate) were not inhibited significantly by CGRP(8-37) co-incubation (P 0.05). NO donors also were incubated with aortic strips, and NTG and PA alone induced significant formation of hydroxylamine, a NO(-) metabolite (232.4 and 364.9%, respectively, P < 0.05). These results indicate that only NTG and PA, and to a lesser extent SIN-1, stimulate the release of CGRP from the rat aorta, which subsequently contributes to the vasodilatory activity of these agents. The hydroxylamine formation suggests a possible link between NO(-) generation and CGRP release from the vascular wall.
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Affiliation(s)
- B P Booth
- Department of Pharmaceutics, School of Pharmacy, State University of New York at Buffalo, Buffalo, NY, USA.
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21
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Production of nitroxyl (HNO) at biologically relevant temperatures from the retro-Diels–Alder reaction of N-hydroxyurea-derived acyl nitroso-9,10-dimethylanthracene cycloadducts. Tetrahedron Lett 2000. [DOI: 10.1016/s0040-4039(00)00670-5] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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22
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Affiliation(s)
- Rong Lin
- Department of Chemistry, University of California, Irvine Irvine, California 92697-2025
| | - Patrick J. Farmer
- Department of Chemistry, University of California, Irvine Irvine, California 92697-2025
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23
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Shirota FN, DeMaster EG, Lee MJ, Nagasawa HT. Generation of nitric oxide and possibly nitroxyl by nitrosation of sulfohydroxamic acids and hydroxamic acids. Nitric Oxide 1999; 3:445-53. [PMID: 10637122 DOI: 10.1006/niox.1999.0257] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Diazeniumdiolates (NONOates) and sulfohydroxamic acids are chemical entities that spontaneously generate nitric oxide (NO) and nitroxyl (HNO), respectively, at physiological pH and temperature. By combining the functional aspects of the NONOates with the hydroxamic acids and sulfohydroxamic acids, hybrid NONOate-type compounds that could theoretically generate nitroxyl or nitric oxide can be rationalized. Although the instability of these compounds, viz., the N-nitrosohydroxamic acids and the N-nitrososulfohydroxamic acids, precluded their chemical characterization by actual isolation, their transient existence was deduced by identification of the products of their decomposition. Thus, treatment of benzohydroxamic acid (BHA) with limiting or excess nitrous acid (from NaNO(2) and H(3)PO(4)) gave rise to quantitative generation of N(2)O, possibly via HNO, based on the limiting reactant. Nitrosation of N-t-butyloxycarbonyl hydroxylamine gave similar results. The organic acid produced from BHA was identified as benzoic acid. No nitric oxide was detected from these reactions. In contrast, treatment of Piloty's acid (benzenesulfohydroxamic acid) and methanesulfohydroxamic acid (MSHA) with nitrous acid under the same conditions as above gave 36% of the theoretical quantity of NO from Piloty's acid and 47% of NO from MSHA, although finite quantities of HNO (measured as N(2)O) were also formed. The organic acid produced from Piloty's acid was identified by reverse-phase HPLC as the redox product, benzenesulfinic acid.
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Affiliation(s)
- F N Shirota
- Medical Research Laboratories, VA Medical Center, Minneapolis, Minnesota 55417, USA
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24
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Ohshima H, Gilibert I, Bianchini F. Induction of DNA strand breakage and base oxidation by nitroxyl anion through hydroxyl radical production. Free Radic Biol Med 1999; 26:1305-13. [PMID: 10381204 DOI: 10.1016/s0891-5849(98)00327-x] [Citation(s) in RCA: 72] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Abstract
Nitroxyl anion (NO-), the one-electron reduction product of nitric oxide (NO*), has been reported to be formed under various physiological conditions and to be cytotoxic, although the mechanism responsible for the toxic effects has not been identified. We have studied the effects of NO- generated from Angeli's salt (sodium trioxodinitrate) or Piloty's acid (N-hydoxybenzenesulfonamide) on DNA strand breakage and DNA base oxidation in vitro. Induction of strand breakage was dose- and time-dependent upon incubation of plasmid pBR322 with Angeli's salt or Piloty's acid. Similarly, 8-oxo-2'-deoxyguanosine and malondialdehyde were formed when calf-thymus DNA or 2'-deoxyribose, respectively, were incubated with Angeli's salt. Electron acceptors (ferricyanide, 4-hydroxy-TEMPO), that convert NO to NO*, inhibited the reactions, indicating that NO , but not NO*, is responsible for the reactions. Furthermore, the reactions were also inhibited by the presence of hydroxyl radical (HO*) scavengers, antioxidants, metal chelators and superoxide dismutase and catalase, implying involvement of free HO*. These results suggest that NO- is a possible endogenous source of HO*, that may be formed either directly from the reaction product of NO- with NO* (N2O2*-) or indirectly through H2O2 formation. Thus NO may play an important role as a cause of diverse pathophysiological conditions such as inflammation and neurodegenerative diseases.
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Affiliation(s)
- H Ohshima
- Unit of Endogenous Cancer Risk Factors, International Agency for Research on Cancer, Lyon, France.
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25
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Poderoso JJ, Carreras MC, Schöpfer F, Lisdero CL, Riobó NA, Giulivi C, Boveris AD, Boveris A, Cadenas E. The reaction of nitric oxide with ubiquinol: kinetic properties and biological significance. Free Radic Biol Med 1999; 26:925-35. [PMID: 10232836 DOI: 10.1016/s0891-5849(98)00277-9] [Citation(s) in RCA: 125] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The reaction of nitric oxide (*NO) with ubiquinol-0 and ubiquinol-2, short-chain analogs of coenzyme Q, was examined in anaerobic and aerobic conditions in terms of formation of intermediates and stable molecular products. The chemical reactivity of ubiquinol-0 and ubiquinol-2 towards *NO differed only quantitatively, the reactions of ubiquinol-2 being slightly faster than those of ubiquinol-0. The ubiquinol/*NO reaction entailed oxidation of ubiquinol to ubiquinone and reduction of *NO to NO-, the latter identified by its reaction with metmyoglobin to form nitroxylmyoglobin and indirectly by measurement of nitrous oxide (N2O) by gas chromatography. Both the rate of ubiquinone accumulation and *NO consumption were linearly dependent on ubiquinol and *NO concentrations. The stoichiometry of *NO consumed per either ubiquinone formed or ubiquinol oxidized was 1.86 A 0.34. The reaction of *NO with ubiquinols proceeded with intermediate formation of ubisemiquinones that were detected by direct EPR. The second order rate constants of the reactions of ubiquinol-0 and ubiquinol-2 with *NO were 0.49 and 1.6 x 10(4) M(-1)s(-1), respectively. Studies in aerobic conditions revealed that the reaction of *NO with ubiquinols was associated with O2 consumption. The formation of oxyradicals - identified by spin trapping EPR- during ubiquinol autoxidation was inhibited by *NO, thus indicating that the O2 consumption triggered by *NO could not be directly accounted for in terms of oxyradical formation or H2O2 accumulation. It is suggested that oxyradical formation is inhibited by the rapid removal of superoxide anion by *NO to yield peroxynitrite, which subsequently may be involved in the propagation of ubiquinol oxidation. The biological significance of the reaction of ubiquinols with *NO is discussed in terms of the cellular O2 gradients, the steady-state levels of ubiquinols and *NO, and the distribution of ubiquinone (largely in its reduced form) in biological membranes with emphasis on the inner mitochondrial membrane.
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Affiliation(s)
- J J Poderoso
- Laboratory of Oxygen Metabolism, University Hospital, University of Buenos Aires, Argentina
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26
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Affiliation(s)
- S B King
- Department of Chemistry, Wake Forest University, Winston-Salem, North Carolina 27109, USA
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27
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Shoeman DW, Nagasawa HT. The reaction of nitroxyl (HNO) with nitrosobenzene gives cupferron (N-nitrosophenylhydroxylamine). Nitric Oxide 1998; 2:66-72. [PMID: 9706744 DOI: 10.1006/niox.1998.0166] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Nitroxyl (HNO), a penultimate product in the NOS-catalyzed conversion of L-arginine to L-citrulline, generated from Angeli's salt (AS) was determined by trapping it with nitrosobenzene (NB) to produce cupferron. The cupferron thus produced was characterized by complexation with Fe3+, Al3+, Cu2+, or Sn2+. UV/VIS spectra of the solubilized (in CHCl3) precipitates formed from NB and nitroxyl generated from AS in the presence of the iron, aluminum, copper, or tin salts were identical to those of their corresponding cupferron complexes. The identities of the Fe3+ and Cu2+ complexes formed from NB and HNO were further confirmed by their identical retention times on HPLC when compared to authentic Fe3+ and Cu2+ cupferron complexes. It was possible to detect 5 x 10(-6) M of the cupferron Fe3+ complex spectrophotometrically and to measure its production from the nitroxyl generators AS and methanesulfohydroxamic acid (MSHA) in the presence of 10(-4) M NB. The yield of cupferron was 51 and 62% of the amount of nitroxyl possible from AS or MSHA, respectively, after taking into account the relative rates of nitroxyl generation from these donors.
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Affiliation(s)
- D W Shoeman
- Medical Research Laboratories, VA Medical Center, Minneapolis, Minnesota 55417, USA
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28
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Reactions of acyl nitroso compounds with amines: Production of nitroxyl (HNO) with the preparation of amides. Tetrahedron Lett 1996. [DOI: 10.1016/s0040-4039(97)82943-7] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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29
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Dierks EA, Burstyn JN. Nitric oxide (NO), the only nitrogen monoxide redox form capable of activating soluble guanylyl cyclase. Biochem Pharmacol 1996; 51:1593-600. [PMID: 8687474 DOI: 10.1016/0006-2952(96)00078-0] [Citation(s) in RCA: 86] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
In the present study, we determined that of the redox forms of nitrogen monoxide, NO-, NO and NO+, only NO significantly activates soluble guanylyl cyclase (GTP pyrophosphate-lyase cyclizing, EC 4.6.1.2). Neither of the NO-donors tested, Angeli's salt (Na2N2O3) or Piloty's acid (C6H5SO2NHOH), caused a change in the guanylyl cyclase activity relative to the basal activity level. Interference by other reaction products was eliminated as a possible explanation for the lack of activation. To the extent that NO+ could be stabilized in aqueous solution, by dissolution of the nitrosonium salt NOPF6 in dry organic solvent prior to addition to the enzyme in buffer, NO+ had no effect on the activity of soluble guanylyl cyclase. The counter-ion, PF6-, had a minimal effect on the enzyme activity and, therefore was, not responsible for the lack of activation by NO+. These observations suggest that NO- is the natural activator of soluble guanylyl cyclase and is reasonably identical with endothelium-derived relaxing factor, the physiological regulator of soluble guanylyl cyclase activity.
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Affiliation(s)
- E A Dierks
- Department of Chemistry, University of Wisconsin, Madison 53706, USA
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30
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Yoo J, Fukuto JM. Oxidation of N-hydroxyguanidine by nitric oxide and the possible generation of vasoactive species. Biochem Pharmacol 1995; 50:1995-2000. [PMID: 8849325 DOI: 10.1016/0006-2952(95)02098-5] [Citation(s) in RCA: 23] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
It has been reported previously that the N-hydroxyguanidine function of N-hydroxy-L-arginine can react with nitric oxide (NO) to generate other species that can act as potent vasodilators with different biological lifetimes than NO. The identities of these species have yet to be determined. Therefore, we have studied the reaction between NO and N-hydroxyguanidine and determined that N-hydroxyguanidine is capable of reducing NO to yield nitrous oxide (N2O) and possibly other nitroso species. It is likely that at least some of the N2O formation in these reactions is due to the initial generation of nitroxyl (HNO). Since HNO has been shown to be a potent vasorelaxant, it is possible that some of the non-NO-mediated biological activity alluded to in previous studies was due to HNO and that other nitroso-species generated in the reaction may also contribute to the overall pharmacological activity by release of either NO or HNO.
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Affiliation(s)
- J Yoo
- Department of Pharmacology, Center for the Health Sciences, UCLA School of Medicine 90095-1735, USA
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31
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Zamora R, Grzesiok A, Weber H, Feelisch M. Oxidative release of nitric oxide accounts for guanylyl cyclase stimulating, vasodilator and anti-platelet activity of Piloty's acid: a comparison with Angeli's salt. Biochem J 1995; 312 ( Pt 2):333-9. [PMID: 8526840 PMCID: PMC1136268 DOI: 10.1042/bj3120333] [Citation(s) in RCA: 81] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
The decomposition of benzenesulphohydroxamic acid (Piloty's acid; PA) and some of its derivatives has been reported to yield nitroxyl ions (NO-), a species with potent vasodilator properties. In a previous study we demonstrated that the oxidative breakdown of PA results in the formation of nitric oxide (NO) and suggested that NO rather than NO- may account for its vasorelaxant properties. Using isolated aortic rings in organ baths, we now show that high concentrations of cysteine potentiate the vasorelaxant response to PA, whereas responses to Angeli's salt (AS), a known generator of NO-, were almost completely inhibited. These different behaviours of PA and AS are mirrored by their distinct chemistries. By using HPLC it was shown that, at physiological pH and in the absence of oxidizing conditions, PA is a relatively stable compound. Direct chemical determination of NO, stimulation of soluble guanylyl cyclase, and measurement of platelet aggregation under various experimental conditions confirmed the requirement for oxidation to release NO from PA, and quite weak oxidants were found to be sufficient to promote this reaction. In contrast, at pH 7.4 AS decomposed rapidly to yield nitrite (NO2-) and NO-, bu did not produce NO on reaction with dioxygen (O2) or hydrogen peroxide (H2O2). Thus sulphohydroxamic acids are a new class of thiol-independent NO-donors that generate NO rather than NO- under physiological conditions.
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Affiliation(s)
- R Zamora
- Department of Nitric Oxide Research, Schwarz Pharma AG, Monheim, Federal Republic of Germany
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32
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Abstract
Nitric oxide (NO) is a highly reactive free radical with a multitude of organ specific regulatory functions. Since 1985, NO has been the subject of numerous research efforts and as a result, has been found to play a major role in the cardiovascular, pulmonary, gastrointestinal, immune, and central nervous systems. In addition, deranged NO synthesis is the basis for a number of pathophysiologic states, such as atherosclerosis, pulmonary hypertension, pyloric stenosis, and the hypertension associated with renal failure. Traditional NO donors such as sodium nitroprusside and new pharmacologic NO adducts such as S-nitrosothiols may serve as exogenous sources of NO for the treatment of NO-deficient pathologic states. This review is an attempt to acquaint the surgical community with the fundamentals of NO biochemistry and physiology. Increased knowledge of its functions in normal homeostasis and pathologic states will enable physicians to better understand these disease processes and utilize new pharmacologic therapies.
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Affiliation(s)
- P C Kuo
- Division of Transplantation Surgery, Stanford University Medical Center, California 94305, USA
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Fukuto JM, Gulati P, Nagasawa HT. Involvement of nitroxyl (HNO) in the cyanamide-induced vasorelaxation of rabbit aorta. Biochem Pharmacol 1994; 47:922-4. [PMID: 8135870 DOI: 10.1016/0006-2952(94)90495-2] [Citation(s) in RCA: 26] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
Relaxation of precontracted rabbit aortic rings in vitro by cyanamide, a clinically used alcohol deterrent drug, required catalase and H2O2, suggesting that a bioactivation mechanism was involved. Since the oxidation of cyanamide by catalase/H2O2 had been shown previously to lead to nitroxyl (HNO) generation via the intermediate N-hydroxycyanamide, and aortic ring relaxation was inhibited by the catalase inhibitor, 3-aminotriazole, HNO appears to be responsible for the vasorelaxation mediated by cyanamide. This was further supported by the observation that N,O-dibenzoyl-N-hydroxycyanamide (DBHC), a derivative of N-hydroxycyanamide that releases HNO in the absence of catalase/H2O2, was a potent vasorelaxant, with an EC50 of 4.2 +/- 1.3 x 10(-6) M.
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Affiliation(s)
- J M Fukuto
- Department of Pharmacology, UCLA School of Medicine 90024-1735
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Affiliation(s)
- J F Kerwin
- Pharmaceutical Products Division, Abbott Laboratories, Abbott Park, Illinois 60064
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