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Sun HJ, Wu ZY, Nie XW, Wang XY, Bian JS. An Updated Insight Into Molecular Mechanism of Hydrogen Sulfide in Cardiomyopathy and Myocardial Ischemia/Reperfusion Injury Under Diabetes. Front Pharmacol 2021; 12:651884. [PMID: 34764865 PMCID: PMC8576408 DOI: 10.3389/fphar.2021.651884] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2021] [Accepted: 09/23/2021] [Indexed: 12/13/2022] Open
Abstract
Cardiovascular diseases are the most common complications of diabetes, and diabetic cardiomyopathy is a major cause of people death in diabetes. Molecular, transcriptional, animal, and clinical studies have discovered numerous therapeutic targets or drugs for diabetic cardiomyopathy. Within this, hydrogen sulfide (H2S), an endogenous gasotransmitter alongside with nitric oxide (NO) and carbon monoxide (CO), is found to play a critical role in diabetic cardiomyopathy. Recently, the protective roles of H2S in diabetic cardiomyopathy have attracted enormous attention. In addition, H2S donors confer favorable effects in myocardial infarction, ischaemia-reperfusion injury, and heart failure under diabetic conditions. Further studies have disclosed that multiplex molecular mechanisms are responsible for the protective effects of H2S against diabetes-elicited cardiac injury, such as anti-oxidative, anti-apoptotic, anti-inflammatory, and anti-necrotic properties. In this review, we will summarize the current findings on H2S biology and pharmacology, especially focusing on the novel mechanisms of H2S-based protection against diabetic cardiomyopathy. Also, the potential roles of H2S in diabetes-aggravated ischaemia-reperfusion injury are discussed.
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Affiliation(s)
- Hai-Jian Sun
- Department of Pharmacology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore
| | - Zhi-Yuan Wu
- Department of Pharmacology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore
| | - Xiao-Wei Nie
- Department of Pharmacology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore
| | - Xin-Yu Wang
- Department of Endocrinology, The First Affiliated Hospital of Shenzhen University (Shenzhen Second People's Hospital), Shenzhen, China
| | - Jin-Song Bian
- Department of Pharmacology, School of Medicine, Southern University of Science and Technology, Shenzhen, China.,National University of Singapore (Suzhou) Research Institute, Suzhou, China
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Guo Y, Xu J, Deng Y, Wu L, Wang J, An J. In vivo effects of nitrosyl hydrogen on cardiac function and sarcoplasmic reticulum calcium pump (SERCA2a) in rats with heart failure after myocardial infarction. Cardiovasc Diagn Ther 2020; 10:1795-1804. [PMID: 33381424 DOI: 10.21037/cdt-20-201] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Background Abnormal Ca2+ circulation in cardiomyocytes is an important cause of decreased myocardial contractility in failing hearts. Nitroxyl hydrogen (HNO) can oxidize Ca2+ cycle-related proteins, alter their biological functions, promote Ca2+ recovery as well as release, and enhance myocardial contractility. In this study, we aim to observe the effect of nitrosyl hydrogen (HNO) on the cardiac function of rats with heart failure and elucidate the underlying mechanism. Methods Twenty six male Wistar rats were randomly divided into heart failure group (HF group), Angeli's salt treatment group (HF + AS group) and sham operation group (Sham group). The HF + AS group rats were treated with HNO donor Angeli's salt by intraperitoneal injection of 1 mg/kg/d, and the rats in the HF group and the Sham group were given the same amount of normal saline. Cardiac function was measured by echocardiography before and after treatment. NT-proBNP was measured by enzyme immunoassay (ELISA) kit after treatment. Western blot were used to measure the expression of sarcoplasmic reticulum Ca2+-ATPase (SERCA) in protein levels in rats. The activities of SERCA2a were detected by the biochemical kit finally. Results We found that Nitrosyl hydrogen could significantly increase LVEF, +dp/dt, -dp/dt (P<0.05), significantly decrease NT-ProBNP and LVEDP (P<0.01), and significantly enhance the activities of SERCA2a protein (P<0.05). Conclusions These findings suggest that Nitrosyl hydrogen could improve the cardiac function possibly by increasing protein activities of SERCA2a in rats.
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Affiliation(s)
- Yanqing Guo
- Department of Cardiology, Shanxi Cardiovascular Hospital, Taiyuan, China
| | - Jiyao Xu
- Department of Cardiology, Shanxi Cardiovascular Hospital, Taiyuan, China
| | - Yongzhi Deng
- Department of Cardiovascular Surgery, Shanxi Cardiovascular Hospital, Taiyuan, China
| | - Li Wu
- Department of Cardiology, Shanxi Cardiovascular Hospital, Taiyuan, China
| | - Jingping Wang
- Department of Cardiology, Shanxi Cardiovascular Hospital, Taiyuan, China
| | - Jian An
- Department of Cardiology, Shanxi Cardiovascular Hospital, Taiyuan, China
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Sun HJ, Wu ZY, Cao L, Zhu MY, Nie XW, Huang DJ, Sun MT, Bian JS. Role of nitroxyl (HNO) in cardiovascular system: From biochemistry to pharmacology. Pharmacol Res 2020; 159:104961. [DOI: 10.1016/j.phrs.2020.104961] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/08/2020] [Revised: 05/16/2020] [Accepted: 05/24/2020] [Indexed: 12/12/2022]
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Cardiovascular Therapeutic Potential of the Redox Siblings, Nitric Oxide (NO•) and Nitroxyl (HNO), in the Setting of Reactive Oxygen Species Dysregulation. Handb Exp Pharmacol 2020; 264:311-337. [PMID: 32813078 DOI: 10.1007/164_2020_389] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Reactive oxygen species (ROS) dysregulation is a hallmark of cardiovascular disease, characterised by an imbalance in the synthesis and removal of ROS. ROS such as superoxide (•O2-), hydrogen peroxide (H2O2), hydroxyl (OH•) and peroxynitrite (ONOO-) have a marked impact on cardiovascular function, contributing to the vascular impairment and cardiac dysfunction associated with diseases such as angina, hypertension, diabetes and heart failure. Central to the vascular dysfunction is a reduction in bioavailability and/or physiological effects of vasoprotective nitric oxide (NO•), leading to vasoconstriction, inflammation and vascular remodelling. In a cardiac context, increased ROS generation can also lead to modification of key proteins involved in cardiac contractility. Whilst playing a key role in the pathogenesis of cardiovascular disease, ROS dysregulation also limits the clinical efficacy of current therapies, such as nitrosovasodilators. As such, alternate therapies are sought. This review will discuss the impact of ROS dysregulation on the therapeutic utility of NO• and its redox sibling, nitroxyl (HNO). Both nitric oxide (NO) and nitroxyl (HNO) donors signal through soluble guanylyl cyclase (sGC). NO binds to the Fe(II) form of sGC and nitroxyl possibly to both sGC heme and thiol groups. In the vasculature, nitroxyl can also signal through voltage-dependent (Kv) and ATP-sensitive (KATP) K+ channels as well as calcitonin gene-related peptide (CGRP). In the heart, HNO directly targets critical thiols to increase myocardial contractility, an effect not seen with NO. The qualitative effects via elevation of cGMP are similar, i.e. lusitropic in the heart and inhibitory on vasoconstriction, inflammation, aggregation and vascular remodelling. Of pathophysiological significance is the fact the efficacy of NO donors is impaired by ROS, e.g. through chemical scavenging of NO, to generate reactive nitrogen oxide species (RNOS), whilst nitroxyl is apparently not.
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Qin CX, Anthonisz J, Leo CH, Kahlberg N, Velagic A, Li M, Jap E, Woodman OL, Parry LJ, Horowitz JD, Kemp-Harper BK, Ritchie RH. Nitric Oxide Resistance, Induced in the Myocardium by Diabetes, Is Circumvented by the Nitric Oxide Redox Sibling, Nitroxyl. Antioxid Redox Signal 2020; 32:60-77. [PMID: 31680536 DOI: 10.1089/ars.2018.7706] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Aim: Impairment of tissue responsiveness to exogenous and endogenous nitric oxide (NO•), known as NO• resistance, occurs in many cardiovascular disease states, prominently in diabetes and especially in the presence of marked hyperglycemia. In this study, we sought to determine in moderate and severe diabetes (i) whether NO• resistance also occurs in the myocardium, and (ii) whether the NO• redox sibling nitroxyl (HNO) circumvents this. Results: The spectrum of acute NO• effects (induced by diethylamine-NONOate), including vasodilation, and enhanced myocardial contraction and relaxation were impaired by moderately diabetic rats ([blood glucose] ∼20 mM). In contrast, acute HNO effects (induced by isopropylamine-NONOate) were preserved even in more severe diabetes ([blood glucose] >28 mM). Intriguingly, the positive inotropic effects of HNO were significantly enhanced in diabetic rat hearts. Further, progressive attenuation of soluble guanylyl cyclase (sGC) contribution to myocardial NO• responses occurred with increasing severity of diabetes. Nevertheless, activation of sGC by HNO remained intact in the myocardium. Innovation: Diabetes is associated with marked attenuation of vascular and myocardial effects of NO and NO donors, and this NO• resistance is circumvented by HNO, suggesting potential therapeutic utility for HNO donors in cardiovascular emergencies in diabetics. Conclusion: These results provide the first evidence that NO• resistance occurs in diabetic hearts, and that HNO largely circumvents this problem. Further, the positive inotropic and lusitropic effects of HNO are enhanced in a severely diabetic myocardium, a finding that warrants further mechanistic interrogation. The results support a potential role for therapeutic HNO administration in acute treatment of ischemia and/or heart failure in diabetics.
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Affiliation(s)
- Cheng Xue Qin
- Heart Failure Pharmacology, Baker Heart & Diabetes Institute, Melbourne, Australia.,Department of Pharmacology and Therapeutics, University of Melbourne, Melbourne, Australia.,Department of Medicine (Central Clinical School), Monash University, Melbourne, Australia
| | - Jarryd Anthonisz
- Heart Failure Pharmacology, Baker Heart & Diabetes Institute, Melbourne, Australia.,Department of Medicine (Central Clinical School), Monash University, Melbourne, Australia
| | - Chen Huei Leo
- School of Biosciences, University of Melbourne, Parkville, Australia.,Science and Maths Cluster, Singapore University of Technology & Design, Singapore Singapore
| | - Nicola Kahlberg
- School of Biosciences, University of Melbourne, Parkville, Australia
| | - Anida Velagic
- Heart Failure Pharmacology, Baker Heart & Diabetes Institute, Melbourne, Australia.,Department of Medicine (Central Clinical School), Monash University, Melbourne, Australia
| | - Mandy Li
- Heart Failure Pharmacology, Baker Heart & Diabetes Institute, Melbourne, Australia
| | - Edwina Jap
- Heart Failure Pharmacology, Baker Heart & Diabetes Institute, Melbourne, Australia
| | - Owen L Woodman
- Heart Failure Pharmacology, Baker Heart & Diabetes Institute, Melbourne, Australia
| | - Laura J Parry
- School of Biosciences, University of Melbourne, Parkville, Australia
| | - John D Horowitz
- Cardiology Unit, The Queen Elizabeth Hospital, Basil Hetzel Institute, The University of Adelaide, Woodville SA, Australia
| | - Barbara K Kemp-Harper
- Department of Pharmacology, Biomedicine Discovery Institute, Monash University, Clayton, Australia
| | - Rebecca H Ritchie
- Heart Failure Pharmacology, Baker Heart & Diabetes Institute, Melbourne, Australia.,Department of Pharmacology and Therapeutics, University of Melbourne, Melbourne, Australia.,Department of Medicine (Central Clinical School), Monash University, Melbourne, Australia
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6
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Fukuto JM. A recent history of nitroxyl chemistry, pharmacology and therapeutic potential. Br J Pharmacol 2019; 176:135-146. [PMID: 29859009 PMCID: PMC6295406 DOI: 10.1111/bph.14384] [Citation(s) in RCA: 42] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2018] [Accepted: 05/23/2018] [Indexed: 12/11/2022] Open
Abstract
Due to the excitement surrounding the discovery of NO as an endogenously generated signalling molecule, a number of other nitrogen oxides were also investigated as possible physiological mediators. Among these was nitroxyl (HNO). Over the past 25 years or so, a significant amount of work by this laboratory and many others has disclosed that HNO possesses unique chemical properties and important pharmacological utility. Indeed, the pharmacological potential for HNO as a treatment for heart failure, among other uses, has garnered this curious molecule a considerable amount of recent attention. This review summarizes the events that led to this recent attention as well as poses important questions that are still to be answered with regards to understanding the chemistry and biology of HNO. LINKED ARTICLES: This article is part of a themed section on Nitric Oxide 20 Years from the 1998 Nobel Prize. To view the other articles in this section visit http://onlinelibrary.wiley.com/doi/10.1111/bph.v176.2/issuetoc.
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Affiliation(s)
- Jon M Fukuto
- Department of ChemistrySonoma State UniversityRohnert ParkCAUSA
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Cortese-Krott MM, Butler AR, Woollins JD, Feelisch M. Inorganic sulfur-nitrogen compounds: from gunpowder chemistry to the forefront of biological signaling. Dalton Trans 2016; 45:5908-19. [PMID: 26898846 DOI: 10.1039/c5dt05034k] [Citation(s) in RCA: 53] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
The reactions between inorganic sulfur and nitrogen-bearing compounds to form S-N containing species have a long history and, besides assuming importance in industrial synthetic processes, are of relevance to microbial metabolism; waste water treatment; aquatic, soil and atmospheric chemistry; and combustion processes. The recent discovery that hydrogen sulfide and nitric oxide exert often similar, sometimes mutually dependent effects in a variety of biological systems, and that the chemical interaction of these two species leads to formation of S-N compounds brought this chemistry to the attention of physiologists, biochemists and physicians. We here provide a perspective about the potential role of S-N compounds in biological signaling and briefly review their chemical properties and bioactivities in the context of the chronology of their discovery. Studies of the biological role of NO revealed why its chemistry is ideally suited for the tasks Nature has chosen for it; realising how the distinctive properties of sulfur can enrich this bioactivity does much to revive 'die Freude am experimentellen Spiel' of the pioneers in this field.
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Affiliation(s)
- Miriam M Cortese-Krott
- Cardiovascular Research Laboratory, Department of Cardiology, Pneumology and Angiology, Medical Faculty, Heinrich Heine University of Düsseldorf, Düsseldorf, Germany
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HNO/Thiol Biology as a Therapeutic Target. OXIDATIVE STRESS IN APPLIED BASIC RESEARCH AND CLINICAL PRACTICE 2016. [DOI: 10.1007/978-3-319-30705-3_14] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
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Nitroxyl (HNO): A Reduced Form of Nitric Oxide with Distinct Chemical, Pharmacological, and Therapeutic Properties. OXIDATIVE MEDICINE AND CELLULAR LONGEVITY 2015; 2016:4867124. [PMID: 26770654 PMCID: PMC4685437 DOI: 10.1155/2016/4867124] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/05/2015] [Revised: 08/14/2015] [Accepted: 09/01/2015] [Indexed: 01/18/2023]
Abstract
Nitroxyl (HNO), the one-electron reduced form of nitric oxide (NO), shows a distinct chemical and biological profile from that of NO. HNO is currently being viewed as a vasodilator and positive inotropic agent that can be used as a potential treatment for heart failure. The ability of HNO to react with thiols and thiol containing proteins is largely used to explain the possible biological actions of HNO. Herein, we summarize different aspects related to HNO including HNO donors, chemistry, biology, and methods used for its detection.
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Key bioactive reaction products of the NO/H2S interaction are S/N-hybrid species, polysulfides, and nitroxyl. Proc Natl Acad Sci U S A 2015. [PMID: 26224837 DOI: 10.1073/pnas.1509277112] [Citation(s) in RCA: 209] [Impact Index Per Article: 23.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023] Open
Abstract
Experimental evidence suggests that nitric oxide (NO) and hydrogen sulfide (H2S) signaling pathways are intimately intertwined, with mutual attenuation or potentiation of biological responses in the cardiovascular system and elsewhere. The chemical basis of this interaction is elusive. Moreover, polysulfides recently emerged as potential mediators of H2S/sulfide signaling, but their biosynthesis and relationship to NO remain enigmatic. We sought to characterize the nature, chemical biology, and bioactivity of key reaction products formed in the NO/sulfide system. At physiological pH, we find that NO and sulfide form a network of cascading chemical reactions that generate radical intermediates as well as anionic and uncharged solutes, with accumulation of three major products: nitrosopersulfide (SSNO(-)), polysulfides, and dinitrososulfite [N-nitrosohydroxylamine-N-sulfonate (SULFI/NO)], each with a distinct chemical biology and in vitro and in vivo bioactivity. SSNO(-) is resistant to thiols and cyanolysis, efficiently donates both sulfane sulfur and NO, and potently lowers blood pressure. Polysulfides are both intermediates and products of SSNO(-) synthesis/decomposition, and they also decrease blood pressure and enhance arterial compliance. SULFI/NO is a weak combined NO/nitroxyl donor that releases mainly N2O on decomposition; although it affects blood pressure only mildly, it markedly increases cardiac contractility, and formation of its precursor sulfite likely contributes to NO scavenging. Our results unveil an unexpectedly rich network of coupled chemical reactions between NO and H2S/sulfide, suggesting that the bioactivity of either transmitter is governed by concomitant formation of polysulfides and anionic S/N-hybrid species. This conceptual framework would seem to offer ample opportunities for the modulation of fundamental biological processes governed by redox switching and sulfur trafficking.
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Miao Z, Reisz JA, Mitroka SM, Pan J, Xian M, King SB. A selective phosphine-based fluorescent probe for nitroxyl in living cells. Bioorg Med Chem Lett 2015; 25:16-9. [PMID: 25465170 PMCID: PMC4355083 DOI: 10.1016/j.bmcl.2014.11.041] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2014] [Revised: 11/11/2014] [Accepted: 11/13/2014] [Indexed: 12/31/2022]
Abstract
A novel fluorescein-based fluorescent probe for nitroxyl (HNO) based on the reductive Staudinger ligation of HNO with an aromatic phosphine was prepared. This probe reacts with HNO derived from Angeli's salt and 4-bromo Piloty's acid under physiological conditions without interference by other biological redox species. Confocal microscopy demonstrates this probe detects HNO by fluorescence in HeLa cells and mass spectrometric analysis of cell lysates confirms this probe detects HNO following the proposed mechanism.
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Affiliation(s)
- Zhengrui Miao
- Department of Chemistry, Wake Forest University, Winston-Salem, North Carolina 27109, United States
| | - Julie A. Reisz
- Department of Chemistry, Wake Forest University, Winston-Salem, North Carolina 27109, United States
| | - Susan M. Mitroka
- Department of Chemistry, Wake Forest University, Winston-Salem, North Carolina 27109, United States
| | - Jia Pan
- Department of Chemistry, Washington State University, Pullman, Washington 99164, United States
| | - Ming Xian
- Department of Chemistry, Washington State University, Pullman, Washington 99164, United States
| | - S. Bruce King
- Department of Chemistry, Wake Forest University, Winston-Salem, North Carolina 27109, United States
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12
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Chin KY, Qin C, Cao N, Kemp-Harper BK, Woodman OL, Ritchie RH. The concomitant coronary vasodilator and positive inotropic actions of the nitroxyl donor Angeli's salt in the intact rat heart: contribution of soluble guanylyl cyclase-dependent and -independent mechanisms. Br J Pharmacol 2014; 171:1722-34. [PMID: 24372173 DOI: 10.1111/bph.12568] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2012] [Revised: 12/11/2013] [Accepted: 12/20/2013] [Indexed: 01/01/2023] Open
Abstract
BACKGROUND AND PURPOSE The NO redox sibling nitroxyl (HNO) elicits soluble guanylyl cyclase (sGC)-dependent vasodilatation. HNO has high reactivity with thiols, which is attributed with HNO-enhanced left ventricular (LV) function. Here, we tested the hypothesis that the concomitant vasodilatation and inotropic actions induced by a HNO donor, Angeli's salt (sodium trioxodinitrate), were sGC-dependent and sGC-independent respectively. EXPERIMENTAL APPROACH Haemodynamic responses to Angeli's salt (10 pmol-10 μmol), alone and in the presence of scavengers of HNO (L-cysteine, 4 mM) or of NO [hydroxocobalamin (HXC), 100 μM] or a selective inhibitor of sGC [1H-[1,2,4]oxadiazolo[4,3-a]quinoxalin-1-one (ODQ), 10 μM], a CGRP receptor antagonist (CGRP8-37 , 0.1 μM) or a blocker of voltage-dependent potassium channels [4-aminopyridine (4-AP), 1 mM] were determined in isolated hearts from male rats. KEY RESULTS Angeli's salt elicited concomitant, dose-dependent increases in coronary flow and LV systolic and diastolic function. Both L-cysteine and ODQ shifted (but did not abolish) the dose-response curve of each of these effects to the right, implying contributions from HNO and sGC in both the vasodilator and inotropic actions. In contrast, neither HXC, CGRP8-37 nor 4-AP affected these actions. CONCLUSIONS AND IMPLICATIONS Both vasodilator and inotropic actions of the HNO donor Angeli's salt were mediated in part by sGC-dependent mechanisms, representing the first evidence that sGC contributes to the inotropic and lusitropic action of HNO in the intact heart. Thus, HNO acutely enhances LV contraction and relaxation, while concomitantly unloading the heart, potentially beneficial actions in failing hearts.
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Affiliation(s)
- Kai Yee Chin
- Heart Failure Pharmacology, Baker IDI Heart & Diabetes Institute, Melbourne, Vic., Australia; School of Medical Sciences, RMIT University, Bundoora, Vic., Australia
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Irvine JC, Ravi RM, Kemp-Harper BK, Widdop RE. Nitroxyl donors retain their depressor effects in hypertension. Am J Physiol Heart Circ Physiol 2013; 305:H939-45. [PMID: 23851276 DOI: 10.1152/ajpheart.00630.2012] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Nitroxyl (HNO), the redox congener of nitric oxide, has numerous vasoprotective actions including an ability to induce vasodilation and inhibit platelet aggregation. Given HNO is resistant to scavenging by superoxide and does not develop tolerance, we hypothesised that HNO would retain its in vivo vasodilatory action in the setting of hypertension. The in vitro and in vivo vasodilator properties of the HNO donors Angeli's salt (AS) and isopropylamine/NONOate (IPA/NO) were compared with the NO donor diethylamine/NONOate (DEA/NO) in spontaneously hypertensive rats (SHR) and normotensive [Wistar-Kyoto (WKY) rats]. AS (10, 50, and 200 μg/kg), IPA/NO (10, 50, and 200 μg/kg), and DEA/NO (1, 5, and 20 μg/kg) caused dose-dependent depressor responses in conscious WKY rats of similar magnitude. Depressor responses to AS and IPA/NO were significantly attenuated (P < 0.01) after infusion of the HNO scavenger N-acetyl-l-cysteine (NAC), confirming that AS and IPA/NO function as HNO donors in vivo. In contrast, responses to DEA/NO were unchanged following NAC infusion. Depressor responses to AS and IPA/NO in conscious SHR retained their sensitivity to the inhibitory effects of NAC (P < 0.01), yet those to DEA/NO in SHR were significantly (P < 0.05) enhanced following NAC infusion. Importantly, depressor responses to AS, IPA/NO, and DEA/NO were preserved in hypertension and vasorelaxation to AS and DEA/NO, in isolated aorta, unchanged in SHR as compared with WKY rats. This study has shown for the first time that HNO donors exert antihypertensive effects in vivo and may, therefore, offer a therapeutic alternative to traditional nitrovasodilators in the treatment of cardiovascular disorders such as hypertension.
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Affiliation(s)
- Jennifer C Irvine
- Department of Pharmacology, Monash University, Clayton, Victoria, Australia
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14
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Donzelli S, Fischer G, King BS, Niemann C, DuMond JF, Heeren J, Wieboldt H, Baldus S, Gerloff C, Eschenhagen T, Carrier L, Böger RH, Espey MG. Pharmacological characterization of 1-nitrosocyclohexyl acetate, a long-acting nitroxyl donor that shows vasorelaxant and antiaggregatory effects. J Pharmacol Exp Ther 2012; 344:339-47. [PMID: 23211362 DOI: 10.1124/jpet.112.199836] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Nitroxyl (HNO) donors have potential benefit in the treatment of heart failure and other cardiovascular diseases. 1-Nitrosocyclohexyl acetate (NCA), a new HNO donor, in contrast to the classic HNO donors Angeli's salt and isopropylamine NONOate, predominantly releases HNO and has a longer half-life. This study investigated the vasodilatative properties of NCA in isolated aortic rings and human platelets and its mechanism of action. NCA was applied on aortic rings isolated from wild-type mice and apolipoprotein E-deficient mice and in endothelial-denuded aortae. The mechanism of action of HNO was examined by applying NCA in the absence and presence of the HNO scavenger glutathione (GSH) and inhibitors of soluble guanylyl cyclase (sGC), adenylyl cyclase (AC), calcitonin gene-related peptide receptor (CGRP), and K(+) channels. NCA induced a concentration-dependent relaxation (EC(50), 4.4 µM). This response did not differ between all groups, indicating an endothelium-independent relaxation effect. The concentration-response was markedly decreased in the presence of excess GSH; the nitric oxide scavenger 2-(4-carboxyphenyl)-4,4,5,5-tetramethylimidazoline-1-oxyl-3-oxide had no effect. Inhibitors of sGC, CGRP, and voltage-dependent K(+) channels each significantly impaired the vasodilator response to NCA. In contrast, inhibitors of AC, ATP-sensitive K(+) channels, or high-conductance Ca(2+)-activated K(+) channels did not change the effects of NCA. NCA significantly reduced contractile response and platelet aggregation mediated by the thromboxane A(2) mimetic 9,11-dideoxy-11α,9α-epoxymethanoprostaglandin F(2)(α) in a cGMP-dependent manner. In summary, NCA shows vasoprotective effects and may have a promising profile as a therapeutic agent in vascular dysfunction, warranting further evaluation.
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Affiliation(s)
- Sonia Donzelli
- Department of Experimental Pharmacology and Toxicology, University Medical Center Hamburg-Eppendorf., Martinistr. 52, D-20246 Hamburg, Germany.
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15
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Reisz JA, Zink CN, King SB. Rapid and selective nitroxyl (HNO) trapping by phosphines: kinetics and new aqueous ligations for HNO detection and quantitation. J Am Chem Soc 2011; 133:11675-85. [PMID: 21699183 DOI: 10.1021/ja203652z] [Citation(s) in RCA: 96] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Recent studies distinguish the biological and pharmacological effects of nitroxyl (HNO) from its oxidized/deprotonated product nitric oxide (·NO), but the lack of HNO detection methods limits the understanding its in vivo mechanisms and the identification of endogenous sources. We previously demonstrated that reaction of HNO with triarylphosphines provides aza-ylides and HNO-derived amides, which may serve as stable HNO biomarkers. We now report a kinetic analysis for the trapping of HNO by phosphines, ligations of enzyme-generated HNO, and compatibility studies illustrating the selectivity of phosphines for HNO over other physiologically relevant nitrogen oxides. Quantification of HNO using phosphines is demonstrated using an HPLC-based assay and ligations of phosphine carbamates generate HNO-derived ureas. These results further demonstrate the potential of phosphine probes for reliable biological detection and quantification of HNO.
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Affiliation(s)
- Julie A Reisz
- Department of Chemistry, Wake Forest University, Winston-Salem, North Carolina 27109, USA
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Bullen ML, Miller AA, Andrews KL, Irvine JC, Ritchie RH, Sobey CG, Kemp-Harper BK. Nitroxyl (HNO) as a vasoprotective signaling molecule. Antioxid Redox Signal 2011; 14:1675-86. [PMID: 20673125 DOI: 10.1089/ars.2010.3327] [Citation(s) in RCA: 60] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
Nitroxyl (HNO), the one electron reduced and protonated form of nitric oxide (NO(•)), is rapidly emerging as a novel nitrogen oxide with distinct pharmacology and therapeutic advantages over its redox sibling. Whilst the cardioprotective effects of HNO in heart failure have been established, it is apparent that HNO may also confer a number of vasoprotective properties. Like NO(•), HNO induces vasodilatation, inhibits platelet aggregation, and limits vascular smooth muscle cell proliferation. In addition, HNO can be putatively generated within the vasculature, and recent evidence suggests it also serves as an endothelium-derived relaxing factor (EDRF). Significantly, HNO targets signaling pathways distinct from NO(•) with an ability to activate K(V) and K(ATP) channels in resistance arteries, cause coronary vasodilatation in part via release of calcitonin-gene related peptide (CGRP), and exhibits resistance to scavenging by superoxide and vascular tolerance development. As such, HNO synthesis and bioavailability may be preserved and/or enhanced during disease states, in particular those associated with oxidative stress. Moreover, it may compensate, in part, for a loss of NO(•) signaling. Here we explore the vasoprotective actions of HNO and discuss the therapeutic potential of HNO donors in the treatment of vascular dysfunction.
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Affiliation(s)
- Michelle L Bullen
- Vascular Biology and Immunopharmacology Group, Department of Pharmacology, Monash University, Clayton, Victoria, Australia
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Irvine JC, Kemp-Harper BK, Widdop RE. Chronic administration of the HNO donor Angeli's salt does not lead to tolerance, cross-tolerance, or endothelial dysfunction: comparison with GTN and DEA/NO. Antioxid Redox Signal 2011; 14:1615-24. [PMID: 20849324 DOI: 10.1089/ars.2010.3269] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
Nitroxyl (HNO) displays distinct pharmacology to its redox congener nitric oxide (NO(•)) with therapeutic potential in the treatment of heart failure. It remains unknown if HNO donors are resistant to tolerance development following chronic in vivo administration. Wistar-Kyoto rats received a 3-day subcutaneous infusion of one of the NO(•) donors, glyceryl trinitrate (GTN) or diethylamine/NONOate (DEA/NO), or the HNO donor Angeli's salt (AS). GTN infusion (10 μg/kg/min) resulted in significantly blunted depressor responses to intravenous bolus doses of GTN, demonstrating tolerance development. By contrast, infusion with AS (20 μg/kg/min) or DEA/NO (2 μg/kg/min) did not alter their subsequent depressor responses. Similarly, ex vivo vasorelaxation responses in isolated aortae revealed that GTN infusion elicited a significant 6-fold decrease in the sensitivity to GTN and reduction in the maximum response to acetylcholine (ACh). Chronic infusion of AS or DEA/NO had no effect on subsequent vasorelaxation responses to themselves or to ACh. No functional cross-tolerance between nitrovasodilators was evident, either in vivo or ex vivo, although an impaired ability of a nitrovasodilator to increase tissue cGMP content was not necessarily indicative of a reduced functional response. In conclusion, HNO donors may represent novel therapies for cardiovascular disease with therapeutic potential over clinically used organic nitrates.
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Affiliation(s)
- Jennifer C Irvine
- Department of Pharmacology, Monash University, Clayton, Victoria, Australia
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Jackson MI, Han TH, Serbulea L, Dutton A, Ford E, Miranda KM, Houk K, Wink DA, Fukuto JM. Kinetic feasibility of nitroxyl reduction by physiological reductants and biological implications. Free Radic Biol Med 2009; 47:1130-9. [PMID: 19577638 PMCID: PMC7370859 DOI: 10.1016/j.freeradbiomed.2009.06.034] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/14/2009] [Revised: 06/17/2009] [Accepted: 06/26/2009] [Indexed: 10/20/2022]
Abstract
Nitroxyl (HNO), the one-electron reduced and protonated congener of nitric oxide (NO), is a chemically unique species with potentially important biological activity. Although HNO-based pharmaceuticals are currently being considered for the treatment of chronic heart failure or stroke/transplant-derived ischemia, the chemical events leading to therapeutic responses are not established. The interaction of HNO with oxidants results in the well-documented conversion to NO, but HNO is expected to be readily reduced as well. Recent thermodynamic calculations predict that reduction of HNO is biologically accessible. Herein, kinetic analysis suggests that the reactions of HNO with several mechanistically distinct reductants are also biologically feasible. Product analysis verified that the reductants had in fact been oxidized and that in several instances HNO had been converted to hydroxylamine. Moreover, a theoretical analysis suggests that in the reaction of HNO with thiol reductants, the pathway producing sulfinamide is significantly more favorable than that leading to disulfide. Additionally, simultaneous production of HNO and NO yielded a biphasic oxidative capacity.
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Affiliation(s)
- Matthew I. Jackson
- Interdepartmental Program in Molecular Toxicology, School of Public Health, University of California at Los Angeles, Los Angeles, CA 90095, USA
| | - Tae H. Han
- Department of Chemical Engineering, University of California at Los Angeles, Los Angeles, CA 90095, USA
| | - Laura Serbulea
- Department of Chemistry and Biochemistry, University of California at Los Angeles, Los Angeles, CA 90095, USA
| | - Andrew Dutton
- Department of Chemistry and Biochemistry, University of California at Los Angeles, Los Angeles, CA 90095, USA
| | - Eleonora Ford
- Department of Molecular and Medical Pharmacology, University of California at Los Angeles, Los Angeles, CA 90095, USA
| | | | - K.N. Houk
- Department of Chemistry and Biochemistry, University of California at Los Angeles, Los Angeles, CA 90095, USA
| | - David A. Wink
- Radiation Biology Branch, National Cancer Institute, Bethesda, MD 20892, USA
| | - Jon M. Fukuto
- Department of Chemistry, Sonoma State University, Rohnert Park, CA 94928, USA
- Corresponding author. Fax: +1 707 664 3378. (J.M. Fukuto)
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Miller TW, Cherney MM, Lee AJ, Francoleon NE, Farmer PJ, King SB, Hobbs AJ, Miranda KM, Burstyn JN, Fukuto JM. The effects of nitroxyl (HNO) on soluble guanylate cyclase activity: interactions at ferrous heme and cysteine thiols. J Biol Chem 2009; 284:21788-21796. [PMID: 19531488 PMCID: PMC2755905 DOI: 10.1074/jbc.m109.014282] [Citation(s) in RCA: 85] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
It has been previously proposed that nitric oxide (NO) is the only biologically relevant nitrogen oxide capable of activating the enzyme soluble guanylate cyclase (sGC). However, recent reports implicate HNO as another possible activator of sGC. Herein, we examine the affect of HNO donors on the activity of purified bovine lung sGC and find that, indeed, HNO is capable of activating this enzyme. Like NO, HNO activation appears to occur via interaction with the regulatory ferrous heme on sGC. Somewhat unexpectedly, HNO does not activate the ferric form of the enzyme. Finally, HNO-mediated cysteine thiol modification appears to also affect enzyme activity leading to inhibition. Thus, sGC activity can be regulated by HNO via interactions at both the regulatory heme and cysteine thiols.
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Affiliation(s)
- Thomas W Miller
- Department of Chemistry and Biochemistry, University of California, Los Angeles, California 90095
| | - Melisa M Cherney
- the Department of Chemistry, University of Wisconsin, Madison, Wisconsin 53706
| | - Andrea J Lee
- the Department of Chemistry, University of Wisconsin, Madison, Wisconsin 53706
| | - Nestor E Francoleon
- Department of Chemistry and Biochemistry, University of California, Los Angeles, California 90095
| | - Patrick J Farmer
- the Department of Chemistry, University of California, Irvine, California 92697
| | - S Bruce King
- the Department of Chemistry, Wake Forest University, Winston Salem, North Carolina 27109
| | - Adrian J Hobbs
- Department of Pharmacology, University College London, Medical Sciences Building, Gower Street, London WC1E 6BT, United Kingdom
| | - Katrina M Miranda
- the Department of Chemistry, University of Arizona, Tucson, Arizona 85721
| | - Judith N Burstyn
- the Department of Chemistry, University of Wisconsin, Madison, Wisconsin 53706
| | - Jon M Fukuto
- the Department of Chemistry, Sonoma State University, Rohnert Park, California 94928-3609
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Irvine JC, Ritchie RH, Favaloro JL, Andrews KL, Widdop RE, Kemp-Harper BK. Nitroxyl (HNO): the Cinderella of the nitric oxide story. Trends Pharmacol Sci 2008; 29:601-8. [PMID: 18835046 DOI: 10.1016/j.tips.2008.08.005] [Citation(s) in RCA: 212] [Impact Index Per Article: 13.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2008] [Revised: 08/10/2008] [Accepted: 08/11/2008] [Indexed: 12/22/2022]
Abstract
Until recently, most of the biological effects of nitric oxide (NO) have been attributed to its uncharged state (NO*), yet NO can also exist in the reduced state as nitroxyl (HNO or NO(-)). Putatively generated from both NO synthase (NOS)-dependent and -independent sources, HNO is rapidly emerging as a novel entity with distinct pharmacology and therapeutic advantages over its redox sibling, NO*. Thus, unlike NO*, HNO can target cardiac sarcoplasmic ryanodine receptors to increase myocardial contractility, can interact directly with thiols and is resistant to both scavenging by superoxide (*O2-) and tolerance development. HNO donors are protective in the setting of heart failure in which NO donors have minimal impact. Here, we discuss the unique pharmacology of HNO versus NO* and highlight the therapeutic potential of HNO donors in the treatment of cardiovascular disease.
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Affiliation(s)
- Jennifer C Irvine
- Department of Pharmacology, Monash University, Clayton, VIC, Australia
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Donzelli S, Espey MG, Flores-Santana W, Switzer CH, Yeh GC, Huang J, Stuehr DJ, King SB, Miranda KM, Wink DA. Generation of nitroxyl by heme protein-mediated peroxidation of hydroxylamine but not N-hydroxy-L-arginine. Free Radic Biol Med 2008; 45:578-84. [PMID: 18503778 PMCID: PMC2562766 DOI: 10.1016/j.freeradbiomed.2008.04.036] [Citation(s) in RCA: 63] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/21/2007] [Revised: 04/04/2008] [Accepted: 04/21/2008] [Indexed: 11/29/2022]
Abstract
The chemical reactivity, toxicology, and pharmacological responses to nitroxyl (HNO) are often distinctly different from those of nitric oxide (NO). The discovery that HNO donors may have pharmacological utility for treatment of cardiovascular disorders such as heart failure and ischemia reperfusion has led to increased speculation of potential endogenous pathways for HNO biosynthesis. Here, the ability of heme proteins to utilize H2O2 to oxidize hydroxylamine (NH2OH) or N-hydroxy-L-arginine (NOHA) to HNO was examined. Formation of HNO was evaluated with a recently developed selective assay in which the reaction products in the presence of reduced glutathione (GSH) were quantified by HPLC. Release of HNO from the heme pocket was indicated by formation of sulfinamide (GS(O)NH2), while the yields of nitrite and nitrate signified the degree of intramolecular recombination of HNO with the heme. Formation of GS(O)NH2 was observed upon oxidation of NH2OH, whereas NOHA, the primary intermediate in oxidation of L-arginine by NO synthase, was apparently resistant to oxidation by the heme proteins utilized. In the presence of NH2OH, the highest yields of GS(O)NH2 were observed with proteins in which the heme was coordinated to a histidine (horseradish peroxidase, lactoperoxidase, myeloperoxidase, myoglobin, and hemoglobin) in contrast to a tyrosine (catalase) or cysteine (cytochrome P450). That peroxidation of NH2OH by horseradish peroxidase produced free HNO, which was able to affect intracellular targets, was verified by conversion of 4,5-diaminofluorescein to the corresponding fluorophore within intact cells.
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Affiliation(s)
- Sonia Donzelli
- Tumor Biology Section, Radiation Biology Branch, National Cancer Institute, NIH, Bethesda, MD 20892, USA.
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Paolocci N, Jackson MI, Lopez BE, Tocchetti CG, Wink DA, Hobbs A, Fukuto JM. The pharmacology of nitroxyl (HNO) and its therapeutic potential: not just the Janus face of NO. Pharmacol Ther 2007; 113:442-58. [PMID: 17222913 PMCID: PMC3501193 DOI: 10.1016/j.pharmthera.2006.11.002] [Citation(s) in RCA: 193] [Impact Index Per Article: 11.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2006] [Accepted: 11/10/2006] [Indexed: 11/29/2022]
Abstract
Nitroxyl (HNO), the 1-electron reduced and protonated congener of nitric oxide (NO), has received recent attention as a potential pharmacological agent for the treatment of heart failure and as a preconditioning agent for the mitigation of ischemia-reperfusion injury. Interest in the pharmacology and biology of HNO has prompted examination, or in some instances reexamination, of many of its chemical properties. Such studies have provided insight into the chemical basis for the biological effects of HNO, although the biochemical mechanisms for many of these effects remain to be established. In this review, a brief description of the biologically relevant chemistry of HNO is given, followed by a more detailed discussion of the pharmacology and potential toxicology of HNO.
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Affiliation(s)
- Nazareno Paolocci
- Division of Cardiology, Department of Medicine, Johns Hopkins Medical Institutions, Baltimore, MD 21287
| | - Matthew I. Jackson
- Interdepartmental Program in Molecular Toxicology, UCLA School of Public Health, Los Angeles, CA, 90095-1772
| | - Brenda E. Lopez
- Department of Pharmacology, UCLA School of Medicine, Center for the Health Sciences, Los Angeles, CA 90095-1735
| | - Carlo G. Tocchetti
- Division of Cardiology, Department of Medicine, Johns Hopkins Medical Institutions, Baltimore, MD 21287
| | - David A. Wink
- Radiation Biology Branch, National Cancer Institute Bethesda, MD 20892
| | - Adrian Hobbs
- Wolfson Institute for Biomedical Research, University College, Cruciform Building, Gower Street, London, WC1E 6AE, UK
| | - Jon M. Fukuto
- Interdepartmental Program in Molecular Toxicology, UCLA School of Public Health, Los Angeles, CA, 90095-1772
- Department of Pharmacology, UCLA School of Medicine, Center for the Health Sciences, Los Angeles, CA 90095-1735
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Irvine JC, Favaloro JL, Kemp-Harper BK. NO- activates soluble guanylate cyclase and Kv channels to vasodilate resistance arteries. Hypertension 2003; 41:1301-7. [PMID: 12743008 DOI: 10.1161/01.hyp.0000072010.54901.de] [Citation(s) in RCA: 125] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Nitric oxide (NO) plays an important role in the control of vascular tone. Traditionally, its vasorelaxant activity has been attributed to the free radical form of NO (NO*), yet the reduced form of NO (NO-) is also produced endogenously and is a potent vasodilator of large conduit arteries. The effects of NO- in the resistance vasculature remain unknown. This study examines the activity of NO- in rat small isolated mesenteric resistance-like arteries and characterizes its mechanism(s) of action. With the use of standard myographic techniques, the vasorelaxant properties of NO* (NO gas solution), NO- (Angeli's salt), and the NO donor sodium nitroprusside were compared. Relaxation responses to Angeli's salt (pEC50=7.51+/-0.13, Rmax=95.5+/-1.5%) were unchanged in the presence of carboxy-PTIO (NO* scavenger) but those to NO* and sodium nitroprusside were inhibited. l-Cysteine (NO- scavenger) decreased the sensitivity to Angeli's salt (P<0.01) and sodium nitroprusside (P<0.01) but not to NO*. The soluble guanylate cyclase inhibitor ODQ (3 and 10 micromol/L) concentration-dependently inhibited relaxation responses to Angeli's salt (41.0+/-6.0% versus control 93.4+/-1.9% at 10 micromol/L). The voltage-dependent K+ channel inhibitor 4-aminopyridine (1 mmol/L) caused a 9-fold (P<0.01) decrease in sensitivity to Angeli's salt, whereas glibenclamide, iberiotoxin, charybdotoxin, and apamin were without effect. In combination, ODQ and 4-aminopyridine abolished the response to Angeli's salt. In conclusion, NO- functions as a potent vasodilator of resistance arteries, mediating its response independently of NO* and through the activation of soluble guanylate cyclase and voltage-dependent K+ channels. NO- donors may represent a novel class of nitrovasodilator relevant for the treatment of cardiovascular disorders such as angina.
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Affiliation(s)
- Jennifer C Irvine
- Department of Pharmacology, Monash University, Clayton Victoria 3800, Australia
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