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Griffiths K, Lee JJ, Frenneaux MP, Feelisch M, Madhani M. Nitrite and myocardial ischaemia reperfusion injury. Where are we now? Pharmacol Ther 2021; 223:107819. [PMID: 33600852 DOI: 10.1016/j.pharmthera.2021.107819] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2020] [Accepted: 01/25/2021] [Indexed: 02/06/2023]
Abstract
Cardiovascular disease remains the leading cause of death worldwide despite major advances in technology and treatment, with coronary heart disease (CHD) being a key contributor. Following an acute myocardial infarction (AMI), it is imperative that blood flow is rapidly restored to the ischaemic myocardium. However, this restoration is associated with an increased risk of additional complications and further cardiomyocyte death, termed myocardial ischaemia reperfusion injury (IRI). Endogenously produced nitric oxide (NO) plays an important role in protecting the myocardium from IRI. It is well established that NO mediates many of its downstream functions through the 'canonical' NO-sGC-cGMP pathway, which is vital for cardiovascular homeostasis; however, this pathway can become impaired in the face of inadequate delivery of necessary substrates, in particular L-arginine, oxygen and reducing equivalents. Recently, it has been shown that during conditions of ischaemia an alternative pathway for NO generation exists, which has become known as the 'nitrate-nitrite-NO pathway'. This pathway has been reported to improve endothelial dysfunction, protect against myocardial IRI and attenuate infarct size in various experimental models. Furthermore, emerging evidence suggests that nitrite itself provides multi-faceted protection, in an NO-independent fashion, against a myriad of pathophysiologies attributed to IRI. In this review, we explore the existing pre-clinical and clinical evidence for the role of nitrate and nitrite in cardioprotection and discuss the lessons learnt from the clinical trials for nitrite as a perconditioning agent. We also discuss the potential future for nitrite as a pre-conditioning intervention in man.
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Affiliation(s)
- Kayleigh Griffiths
- Institute of Cardiovascular Sciences, College of Medical and Dental Sciences, University of Birmingham, Birmingham B15 2TT, UK
| | - Jordan J Lee
- Institute of Cardiovascular Sciences, College of Medical and Dental Sciences, University of Birmingham, Birmingham B15 2TT, UK
| | - Michael P Frenneaux
- Norwich Medical School, University of East Anglia, Bob Champion Research and Education Building, Norwich Research Park, Norwich NR4 7UQ, UK
| | - Martin Feelisch
- Clinical and Experimental Sciences, Faculty of Medicine, University of Southampton, Southampton General Hospital, Southampton, UK
| | - Melanie Madhani
- Institute of Cardiovascular Sciences, College of Medical and Dental Sciences, University of Birmingham, Birmingham B15 2TT, UK.
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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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Li W, Yang J, Lyu Q, Wu G, Lin S, Yang Q, Hu J. Taurine attenuates isoproterenol-induced H9c2 cardiomyocytes hypertrophy by improving antioxidative ability and inhibiting calpain-1-mediated apoptosis. Mol Cell Biochem 2020; 469:119-132. [PMID: 32304004 DOI: 10.1007/s11010-020-03733-7] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2020] [Accepted: 04/08/2020] [Indexed: 12/18/2022]
Abstract
Pathological cardiac hypertrophy is ultimately accompanied by cardiomyocyte apoptosis. Apoptosis mainly related to calpain-1-mediated apoptotic pathways. Studies had proved that taurine can maintain heart health through antioxidation and antiapoptotic functions, but the effect of taurine on cardiac hypertrophy is still unclear. This study aimed to determine whether taurine could inhibit calpain-1-mediated mitochondria-dependent apoptotic pathways in isoproterenol (ISO)-induced hypertrophic cardiomyocytes. We found that taurine could inhibit the increase in cell surface area and reduce the protein expression levels of the hypertrophic markers atrial natriuretic peptide, brain natriuretic polypeptide, and β-myosin heavy chain. Taurine also reduced ROS, intracellular Ca2+ overload and mitochondrial membrane potential. Moreover, taurine inhibited cardiomyocyte apoptosis by decreasing the protein expression of calpain-1, Bax, t-Bid, cytosolic cytochrome c, Apaf-1, cleaved caspase-9 and cleaved caspase-3 and by enhancing calpastatin and Bcl-2 protein expression. Calpain-1 small interfering RNA transfection results showed similar antiapoptotic effects as the taurine prevention group. However, compared with the two treatments, taurine inhibited the expression of cleaved caspase-9 more significantly. Therefore, we believe that taurine prevents ISO-induced H9c2 cardiomyocyte hypertrophy by inhibiting oxidative stress, intracellular Ca2+ overload, the calpain-1-mediated mitochondria-dependent apoptotic pathway and cleaved caspase-9 levels.
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Affiliation(s)
- Weiwei Li
- Liaoning Provincial Key Laboratory of Zoonosis, College of Animal Science and Veterinary Medicine, Shenyang Agricultural University, Shenyang, 110866, Liaoning, People's Republic of China
| | - Jiancheng Yang
- Liaoning Provincial Key Laboratory of Zoonosis, College of Animal Science and Veterinary Medicine, Shenyang Agricultural University, Shenyang, 110866, Liaoning, People's Republic of China
| | - Qiufeng Lyu
- Liaoning Provincial Key Laboratory of Zoonosis, College of Animal Science and Veterinary Medicine, Shenyang Agricultural University, Shenyang, 110866, Liaoning, People's Republic of China
| | - Gaofeng Wu
- Liaoning Provincial Key Laboratory of Zoonosis, College of Animal Science and Veterinary Medicine, Shenyang Agricultural University, Shenyang, 110866, Liaoning, People's Republic of China
| | - Shumei Lin
- Liaoning Provincial Key Laboratory of Zoonosis, College of Animal Science and Veterinary Medicine, Shenyang Agricultural University, Shenyang, 110866, Liaoning, People's Republic of China
| | - Qunhui Yang
- Liaoning Provincial Key Laboratory of Zoonosis, College of Animal Science and Veterinary Medicine, Shenyang Agricultural University, Shenyang, 110866, Liaoning, People's Republic of China.
| | - Jianmin Hu
- Liaoning Provincial Key Laboratory of Zoonosis, College of Animal Science and Veterinary Medicine, Shenyang Agricultural University, Shenyang, 110866, Liaoning, People's Republic of China.
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Mulkareddy V, Racette SB, Coggan AR, Peterson LR. Dietary nitrate's effects on exercise performance in heart failure with reduced ejection fraction (HFrEF). Biochim Biophys Acta Mol Basis Dis 2019; 1865:735-740. [PMID: 30261290 PMCID: PMC6401215 DOI: 10.1016/j.bbadis.2018.09.026] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2018] [Revised: 09/13/2018] [Accepted: 09/18/2018] [Indexed: 01/09/2023]
Abstract
Heart failure with reduced ejection fraction (HFrEF) is a deadly and disabling disease. A key derangement contributing to impaired exercise performance in HFrEF is decreased nitric oxide (NO) bioavailability. Scientists recently discovered the inorganic nitrate pathway for increasing NO. This has advantages over organic nitrates and NO synthase production of NO. Small studies using beetroot juice as a source of inorganic nitrate demonstrate its power to improve exercise performance in HFrEF. A larger-scale trial is now underway to determine if inorganic nitrate may be a new arrow for physicians' quiver of HFrEF treatments.
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Affiliation(s)
- Vinaya Mulkareddy
- The Department of Medicine, 4960 Children's Place, Campus Box 8066, St. Louis, MO 63110, USA.
| | - Susan B Racette
- The Department of Medicine, 4960 Children's Place, Campus Box 8066, St. Louis, MO 63110, USA; Program in Physical Therapy, Washington University School of Medicine, Campus Box 8502, 4444 Forest Park Ave., St. Louis, MO 63108-2212, USA.
| | - Andrew R Coggan
- Department of Kinesiology, Indiana University Purdue University Indianapolis, 901 West New York Street, Indianapolis, IN 46202, USA; Department of Cellular and Integrative Physiology, Indiana University Purdue University Indianapolis, 901 West New York Street, Indianapolis, IN 46202, USA.
| | - Linda R Peterson
- Department of Medicine, Cardiovascular Division, Washington University School of Medicine, St. Louis, MO, USA.
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Dietary nitrate lowers ambulatory blood pressure in treated, uncontrolled hypertension: a 7-d, double-blind, randomised, placebo-controlled, cross-over trial. Br J Nutr 2018; 119:658-663. [DOI: 10.1017/s0007114518000144] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
AbstractDietary nitrate has been shown to increase nitrate/nitrite levels and decrease blood pressure (BP) in multiple populations. There are few reports among hypertensives and these reports have provided conflicting evidence. We aimed to assess the effect of daily nitrate compared with placebo in subjects with uncontrolled hypertension (HTN). On day 0, hypertensives wore an ambulatory BP monitor (ABPM) for 24 h and blood was taken. Subjects were then randomised to 7-d nitrate-rich beetroot juice (NO3−) (12·9 mmol nitrate) followed by 7-d nitrate-depleted beetroot juice (0·5 mmol nitrate) or vice versa. ABPM and blood were assessed before and after both conditions. In all, twenty subjects with treated yet uncontrolled HTN entered and completed the trial (mean age=62·5 years, mean BMI=30·7 kg/m2). Baseline BP was 137/80 (sd7/7) mmHg. Dietary nitrate was well tolerated and resulted in significantly increased plasma nitrite (P=0·0004) and decreased 24-h systolic BP and diastolic BP compared with placebo (−8 mmHg;P=0·012 and −4 mmHg;P=0·018, respectively). Our results support the existing data suggesting an anti-hypertensive effect of dietary nitrate in treated yet uncontrolled hypertensives. Targeted dietary strategies appear promising contributors to BP control.
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Münzel T, Daiber A. Inorganic nitrite and nitrate in cardiovascular therapy: A better alternative to organic nitrates as nitric oxide donors? Vascul Pharmacol 2018; 102:1-10. [DOI: 10.1016/j.vph.2017.11.003] [Citation(s) in RCA: 36] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2017] [Revised: 11/11/2017] [Accepted: 11/12/2017] [Indexed: 01/08/2023]
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Poole DC, Richardson RS, Haykowsky MJ, Hirai DM, Musch TI. Exercise limitations in heart failure with reduced and preserved ejection fraction. J Appl Physiol (1985) 2017; 124:208-224. [PMID: 29051336 DOI: 10.1152/japplphysiol.00747.2017] [Citation(s) in RCA: 69] [Impact Index Per Article: 9.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023] Open
Abstract
The hallmark symptom of chronic heart failure (HF) is severe exercise intolerance. Impaired perfusive and diffusive O2 transport are two of the major determinants of reduced physical capacity and lowered maximal O2 uptake in patients with HF. It has now become evident that this syndrome manifests at least two different phenotypic variations: heart failure with preserved or reduced ejection fraction (HFpEF and HFrEF, respectively). Unlike HFrEF, however, there is currently limited understanding of HFpEF pathophysiology, leading to a lack of effective pharmacological treatments for this subpopulation. This brief review focuses on the disturbances within the O2 transport pathway resulting in limited exercise capacity in both HFpEF and HFrEF. Evidence from human and animal research reveals HF-induced impairments in both perfusive and diffusive O2 conductances identifying potential targets for clinical intervention. Specifically, utilization of different experimental approaches in humans (e.g., small vs. large muscle mass exercise) and animals (e.g., intravital microscopy and phosphorescence quenching) has provided important clues to elucidating these pathophysiological mechanisms. Adaptations within the skeletal muscle O2 delivery-utilization system following established and emerging therapies (e.g., exercise training and inorganic nitrate supplementation, respectively) are discussed. Resolution of the underlying mechanisms of skeletal muscle dysfunction and exercise intolerance is essential for the development and refinement of the most effective treatments for patients with HF.
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Coggan AR, Broadstreet SR, Mahmood K, Mikhalkova D, Madigan M, Bole I, Park S, Leibowitz JL, Kadkhodayan A, Thomas DP, Thies D, Peterson LR. Dietary Nitrate Increases VO 2peak and Performance but Does Not Alter Ventilation or Efficiency in Patients With Heart Failure With Reduced Ejection Fraction. J Card Fail 2017; 24:65-73. [PMID: 28916479 DOI: 10.1016/j.cardfail.2017.09.004] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2017] [Revised: 09/01/2017] [Accepted: 09/06/2017] [Indexed: 11/16/2022]
Abstract
BACKGROUND Patients with heart failure with reduced ejection fraction (HFrEF) exhibit lower efficiency, dyspnea, and diminished peak oxygen uptake (VO2peak) during exercise. Dietary nitrate (NO3-), a source of nitric oxide (NO), has improved these measures in some studies of other populations. We determined the effects of acute NO3- ingestion on exercise responses in 8 patients with HFrEF using a randomized, double-blind, placebo-controlled, crossover design. METHODS AND RESULTS Plasma NO3-, nitrite (NO2-), and breath NO were measured at multiple time points and respiratory gas exchange was determined during exercise after ingestion of beetroot juice containing or devoid of 11.2 mmol of NO3-. NO3- intake increased (P < .05-0.001) plasma NO3- and NO2- and breath NO by 1469 ± 245%, 105 ± 34%, and 60 ± 18%, respectively. Efficiency and ventilation during exercise were unchanged. However, NO3- ingestion increased (P < .05) VO2peak by 8 ± 2% (ie, from 21.4 ± 2.1 to 23.0 ± 2.3 mL.min-1.kg-1). Time to fatigue improved (P < .05) by 7 ± 3 % (ie, from 582 ± 84 to 612 ± 81 seconds). CONCLUSIONS Acute dietary NO3- intake increases VO2peak and performance in patients with HFrEF. These data, in conjunction with our recent data demonstrating that dietary NO3- also improves muscle contractile function, suggest that dietary NO3- supplementation may be a valuable means of enhancing exercise capacity in this population.
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Affiliation(s)
- Andrew R Coggan
- Department of Kinesiology, Indiana University Purdue University Indianapolis, Indianapolis, Indiana; Department of Cellular and Integrative Physiology, Indiana University Purdue University Indianapolis, Indianapolis, Indiana; Department of Radiology, Washington University School of Medicine, St. Louis, Missouri.
| | - Seth R Broadstreet
- Department of Kinesiology, Indiana University Purdue University Indianapolis, Indianapolis, Indiana
| | - Kiran Mahmood
- Department of Medicine, Washington University School of Medicine, St. Louis, Missouri
| | - Deana Mikhalkova
- Department of Medicine, Washington University School of Medicine, St. Louis, Missouri
| | - Michael Madigan
- Department of Medicine, Washington University School of Medicine, St. Louis, Missouri
| | - Indra Bole
- Department of Medicine, Washington University School of Medicine, St. Louis, Missouri
| | - Soo Park
- Department of Medicine, Washington University School of Medicine, St. Louis, Missouri
| | - Joshua L Leibowitz
- Department of Medicine, Washington University School of Medicine, St. Louis, Missouri
| | - Ana Kadkhodayan
- Department of Medicine, Washington University School of Medicine, St. Louis, Missouri
| | - Deepak P Thomas
- Department of Medicine, Washington University School of Medicine, St. Louis, Missouri
| | - Dakkota Thies
- Department of Radiology, Washington University School of Medicine, St. Louis, Missouri
| | - Linda R Peterson
- Department of Radiology, Washington University School of Medicine, St. Louis, Missouri; Department of Medicine, Washington University School of Medicine, St. Louis, Missouri
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Hirai DM, Zelt JT, Jones JH, Castanhas LG, Bentley RF, Earle W, Staples P, Tschakovsky ME, McCans J, O’Donnell DE, Neder JA. Dietary nitrate supplementation and exercise tolerance in patients with heart failure with reduced ejection fraction. Am J Physiol Regul Integr Comp Physiol 2017; 312:R13-R22. [DOI: 10.1152/ajpregu.00263.2016] [Citation(s) in RCA: 51] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2016] [Revised: 10/03/2016] [Accepted: 10/26/2016] [Indexed: 11/22/2022]
Abstract
Endothelial dysfunction and reduced nitric oxide (NO) signaling are key abnormalities leading to skeletal muscle oxygen delivery-utilization mismatch and poor physical capacity in patients with heart failure with reduced ejection fraction (HFrEF). Oral inorganic nitrate supplementation provides an exogenous source of NO that may enhance locomotor muscle function and oxygenation with consequent improvement in exercise tolerance in HFrEF. Thirteen patients (left ventricular ejection fraction ≤40%) were enrolled in a double-blind, randomized crossover study to receive concentrated nitrate-rich (nitrate) or nitrate-depleted (placebo) beetroot juice for 9 days. Low- and high-intensity constant-load cardiopulmonary exercise tests were performed with noninvasive measurements of central hemodynamics (stroke volume, heart rate, and cardiac output via impedance cardiography), arterial blood pressure, pulmonary oxygen uptake, quadriceps muscle oxygenation (near-infrared spectroscopy), and blood lactate concentration. Ten patients completed the study with no adverse clinical effects. Nitrate-rich supplementation resulted in significantly higher plasma nitrite concentration compared with placebo (240 ± 48 vs. 56 ± 8 nM, respectively; P < 0.05). There was no significant difference in the primary outcome of time to exercise intolerance between nitrate and placebo (495 ± 53 vs. 489 ± 58 s, respectively; P > 0.05). Similarly, there were no significant differences in central hemodynamics, arterial blood pressure, pulmonary oxygen uptake kinetics, skeletal muscle oxygenation, or blood lactate concentration from rest to low- or high-intensity exercise between conditions. Oral inorganic nitrate supplementation with concentrated beetroot juice did not present with beneficial effects on central or peripheral components of the oxygen transport pathway thereby failing to improve exercise tolerance in patients with moderate HFrEF.
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Affiliation(s)
- Daniel M. Hirai
- Department of Medicine, Division of Respirology, Laboratory of Clinical Exercise Physiology, Queen’s University, Kingston, Ontario, Canada
- Department of Medicine, Respiratory Division, Pulmonary Function and Clinical Exercise Physiology Unit, Federal University of Sao Paulo, Sao Paulo, Brazil
| | - Joel T. Zelt
- Department of Medicine, Division of Respirology, Laboratory of Clinical Exercise Physiology, Queen’s University, Kingston, Ontario, Canada
| | - Joshua H. Jones
- Department of Medicine, Division of Respirology, Laboratory of Clinical Exercise Physiology, Queen’s University, Kingston, Ontario, Canada
| | - Luiza G. Castanhas
- Department of Medicine, Division of Respirology, Laboratory of Clinical Exercise Physiology, Queen’s University, Kingston, Ontario, Canada
| | - Robert F. Bentley
- School of Kinesiology and Health Studies, Human Vascular Control Laboratory, Queen’s University, Kingston, Ontario, Canada
| | - Wendy Earle
- Department of Medicine, Division of Cardiology, Queen’s University, Kingston, Ontario, Canada; and
| | - Patti Staples
- Department of Medicine, Division of Cardiology, Queen’s University, Kingston, Ontario, Canada; and
| | - Michael E. Tschakovsky
- School of Kinesiology and Health Studies, Human Vascular Control Laboratory, Queen’s University, Kingston, Ontario, Canada
| | - John McCans
- Department of Medicine, Division of Cardiology, Queen’s University, Kingston, Ontario, Canada; and
| | - Denis E. O’Donnell
- Department of Medicine, Division of Respirology, Respiratory Investigation Unit, Queen’s University, Kingston, Ontario, Canada
| | - J. Alberto Neder
- Department of Medicine, Division of Respirology, Laboratory of Clinical Exercise Physiology, Queen’s University, Kingston, Ontario, Canada
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Colburn TD, Ferguson SK, Holdsworth CT, Craig JC, Musch TI, Poole DC. Effect of sodium nitrite on local control of contracting skeletal muscle microvascular oxygen pressure in healthy rats. J Appl Physiol (1985) 2016; 122:153-160. [PMID: 27789769 DOI: 10.1152/japplphysiol.00367.2016] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2016] [Revised: 10/13/2016] [Accepted: 10/20/2016] [Indexed: 12/21/2022] Open
Abstract
Exercise intolerance characteristic of diseases such as chronic heart failure (CHF) and diabetes is associated with reduced nitric oxide (NO) bioavailability from nitric oxide synthase (NOS), resulting in an impaired microvascular O2 driving pressure (Po2mv; O2 delivery/O2 utilization) and metabolic control. Infusions of the potent NO donor sodium nitroprusside augment NO bioavailability yet decrease mean arterial pressure (MAP) thereby reducing its potential efficacy for patient populations. To eliminate or reduce hypotensive sequelae, [Formula: see text] was superfused onto the spinotrapezius muscle. It was hypothesized that local [Formula: see text] administration would elevate resting Po2mv and slow Po2mv kinetics [increased time constant (τ) and mean response time (MRT)] following the onset of muscle contractions without decreasing MAP. In 12 anesthetized male Sprague-Dawley rats, Po2mv of the circulation-intact spinotrapezius muscle was measured by phosphorescence quenching during 180 s of electrically induced twitch contractions (1 Hz) before and after superfusion of sodium nitrite (NaNO2 30 mM). [Formula: see text] superfusion elevated resting Po2mv (control: 28.4 ± 1.1 vs. [Formula: see text]: 31.6 ± 1.2 mmHg; P ≤ 0.05), τ (control: 12.3 ± 1.2 vs. [Formula: see text]: 19.7 ± 2.2 s; P ≤ 0.05), and MRT (control: 19.3 ± 1.9 vs. [Formula: see text]: 25.6 ± 3.3 s; P ≤ 0.05). Importantly, these effects occurred in the absence of any reduction in MAP (103 ± 4 vs. 105 ± 4 mmHg, pre- and postsuperfusion respectively; P > 0.05). These results indicate that [Formula: see text] supplementation delivered to the muscle directly through [Formula: see text] superfusion enhances the blood-myocyte oxygen driving pressure without compromising MAP at rest and following the onset of muscle contraction. This strategy has substantial clinical utility for a range of ischemic conditions. NEW & NOTEWORTHY Ischemic conditions as diverse as chronic heart failure (CHF) and frostbite inflict tissue damage via inadequate O2 delivery. Herein we demonstrate that direct application of sodium nitrite enhances the O2 supply-O2 demand relationship, raising microvascular O2 pressure in healthy skeletal muscle. This therapeutic action of nitrite-derived nitric oxide occurred without inducing systemic hypotension and has the potential to relieve focal ischemia and preserve tissue vitality by enhancing O2 delivery.
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Affiliation(s)
- Trenton D Colburn
- Department of Kinesiology, Kansas State University, Manhattan, Kansas; and
| | - Scott K Ferguson
- Department of Anatomy and Physiology, Kansas State University, Manhattan, Kansas
| | - Clark T Holdsworth
- Department of Anatomy and Physiology, Kansas State University, Manhattan, Kansas
| | - Jesse C Craig
- Department of Kinesiology, Kansas State University, Manhattan, Kansas; and
| | - Timothy I Musch
- Department of Kinesiology, Kansas State University, Manhattan, Kansas; and.,Department of Anatomy and Physiology, Kansas State University, Manhattan, Kansas
| | - David C Poole
- Department of Kinesiology, Kansas State University, Manhattan, Kansas; and .,Department of Anatomy and Physiology, Kansas State University, Manhattan, Kansas
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Chirinos JA, Zamani P. The Nitrate-Nitrite-NO Pathway and Its Implications for Heart Failure and Preserved Ejection Fraction. Curr Heart Fail Rep 2016; 13:47-59. [PMID: 26792295 DOI: 10.1007/s11897-016-0277-9] [Citation(s) in RCA: 45] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
The pathogenesis of exercise intolerance in patients with heart failure and preserved ejection fraction (HFpEF) is likely multifactorial. In addition to cardiac abnormalities (diastolic dysfunction, abnormal contractile reserve, chronotropic incompetence), several peripheral abnormalities are likely to be involved. These include abnormal pulsatile hemodynamics, abnormal arterial vasodilatory responses to exercise, and abnormal peripheral O2 delivery, extraction, and utilization. The nitrate-nitrite-NO pathway is emerging as a potential target to modify key physiologic abnormalities, including late systolic left ventricular (LV) load from arterial wave reflections (which has deleterious short- and long-term consequences for the LV), arterial vasodilatory reserve, muscle O2 delivery, and skeletal muscle mitochondrial function. In a recently completed randomized trial, the administration of a single dose of exogenous inorganic nitrate has been shown to exert various salutary arterial hemodynamic effects, ultimately leading to enhanced aerobic capacity in patients with HFpEF. These effects have the potential for both immediate improvements in exercise tolerance and for long-term "disease-modifying" effects. In this review, we provide an overview of key mechanistic contributors to exercise intolerance in HFpEF, and of the potential therapeutic role of drugs that target the nitrate-nitrite-NO pathway.
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Affiliation(s)
- Julio A Chirinos
- University of Pennsylvania Perelman School of Medicine, Philadelphia, PA, USA. .,Hospital of the University of Pennsylvania, Philadelphia, PA, USA. .,Ghent University, Ghent, Belgium.
| | - Payman Zamani
- University of Pennsylvania Perelman School of Medicine, Philadelphia, PA, USA.,Hospital of the University of Pennsylvania, Philadelphia, PA, USA
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Rix PJ, Vick A, Attkins NJ, Barker GE, Bott AW, Alcorn H, Gladwin MT, Shiva S, Bradley S, Hussaini A, Hoye WL, Parsley EL, Masamune H. Pharmacokinetics, pharmacodynamics, safety, and tolerability of nebulized sodium nitrite (AIR001) following repeat-dose inhalation in healthy subjects. Clin Pharmacokinet 2015; 54:261-72. [PMID: 25421879 PMCID: PMC4335132 DOI: 10.1007/s40262-014-0201-y] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
Introduction The efficacy of nebulized sodium nitrite (AIR001) has been demonstrated in animal models of pulmonary arterial hypertension (PAH), but it was not known if inhaled nitrite would be well tolerated in human subjects at exposure levels associated with efficacy in these models. Methods Inhaled nebulized sodium nitrite was assessed in three independent studies in a total of 82 healthy male and female subjects. Study objectives included determination of the maximum tolerated dose (MTD) and dose-limiting toxicity (DLT) under normal and mildly hypoxic conditions, and following co-administration with steady-state sildenafil, assessment of nitrite pharmacokinetics, and evaluation of the fraction exhaled nitric oxide (FENO) and concentrations of iron-nitrosyl hemoglobin (Hb(Fe)-NO) and S-nitrosothiols (R-SNO) as biomarkers of local and systemic NO exposure, respectively. Results Nebulized sodium nitrite was well tolerated following 6 days of every 8 h administration up to 90 mg, producing significant increases in circulating Hb(Fe)-NO, R-SNO, and FENO. Pulmonary absorption of nitrite was rapid and complete, and plasma exposure dose was proportional through the MTD dosage level of 90 mg, without accumulation following repeated inhalation. At higher dosage levels, DLTs were orthostasis (observed at 120 mg) and hypotension with tachycardia (at 176 mg), but venous methemoglobin did not exceed 3.0 % at any time in any subject. Neither the tolerability nor pharmacokinetics of nitrite was impacted by conditions of mild hypoxia, or co-administration with sildenafil, supporting the safe use of inhaled nitrite in the clinical setting of PAH. Conclusion On the basis of these results, nebulized sodium nitrite (AIR001) has been advanced into randomized trials in PAH patients. Electronic supplementary material The online version of this article (doi:10.1007/s40262-014-0201-y) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Peter J Rix
- Seragon Pharmaceuticals, Inc., 12780 El Camino Real, San Diego, CA, 92130, USA,
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Glean AA, Ferguson SK, Holdsworth CT, Colburn TD, Wright JL, Fees AJ, Hageman KS, Poole DC, Musch TI. Effects of nitrite infusion on skeletal muscle vascular control during exercise in rats with chronic heart failure. Am J Physiol Heart Circ Physiol 2015; 309:H1354-60. [PMID: 26371165 DOI: 10.1152/ajpheart.00421.2015] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/03/2015] [Accepted: 09/02/2015] [Indexed: 11/22/2022]
Abstract
Chronic heart failure (CHF) reduces nitric oxide (NO) bioavailability and impairs skeletal muscle vascular control during exercise. Reduction of NO2 (-) to NO may impact exercise-induced hyperemia, particularly in muscles with pathologically reduced O2 delivery. We tested the hypothesis that NO2 (-) infusion would increase exercising skeletal muscle blood flow (BF) and vascular conductance (VC) in CHF rats with a preferential effect in muscles composed primarily of type IIb + IId/x fibers. CHF (coronary artery ligation) was induced in adult male Sprague-Dawley rats. After a >21-day recovery, mean arterial pressure (MAP; carotid artery catheter) and skeletal muscle BF (radiolabeled microspheres) were measured during treadmill exercise (20 m/min, 5% incline) with and without NO2 (-) infusion. The myocardial infarct size (35 ± 3%) indicated moderate CHF. NO2 (-) infusion increased total hindlimb skeletal muscle VC (CHF: 0.85 ± 0.09 ml·min(-1)·100 g(-1)·mmHg(-1) and CHF + NO2 (-): 0.93 ± 0.09 ml·min(-1)·100 g(-1)·mmHg(-1), P < 0.05) without changing MAP (CHF: 123 ± 4 mmHg and CHF + NO2 (-): 120 ± 4 mmHg, P = 0.17). Total hindlimb skeletal muscle BF was not significantly different (CHF: 102 ± 7 and CHF + NO2 (-): 109 ± 7 ml·min(-1)·100 g(-1) ml·min(-1)·100 g(-1), P > 0.05). BF increased in 6 (∼21%) and VC in 8 (∼29%) of the 28 individual muscles and muscle parts. Muscles and muscle portions exhibiting greater BF and VC after NO2 (-) infusion comprised ≥63% type IIb + IId/x muscle fibers. These data demonstrate that NO2 (-) infusion can augment skeletal muscle vascular control during exercise in CHF rats. Given the targeted effects shown herein, a NO2 (-)-based therapy may provide an attractive "needs-based" approach for treatment of the vascular dysfunction in CHF.
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Affiliation(s)
- Angela A Glean
- Department of Kinesiology, Kansas State University, Manhattan, Kansas
| | - Scott K Ferguson
- Department of Anatomy and Physiology, Kansas State University, Manhattan, Kansas; and
| | - Clark T Holdsworth
- Department of Anatomy and Physiology, Kansas State University, Manhattan, Kansas; and
| | - Trenton D Colburn
- Department of Kinesiology, Kansas State University, Manhattan, Kansas
| | - Jennifer L Wright
- Department of Anatomy and Physiology, Kansas State University, Manhattan, Kansas; and
| | - Alex J Fees
- Department of Anatomy and Physiology, Kansas State University, Manhattan, Kansas; and
| | - Karen S Hageman
- Department of Anatomy and Physiology, Kansas State University, Manhattan, Kansas; and
| | - David C Poole
- Department of Anatomy and Physiology, Kansas State University, Manhattan, Kansas; and Department of Kinesiology, Kansas State University, Manhattan, Kansas
| | - Timothy I Musch
- Department of Anatomy and Physiology, Kansas State University, Manhattan, Kansas; and Department of Kinesiology, Kansas State University, Manhattan, Kansas
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Ferguson SK, Glean AA, Holdsworth CT, Wright JL, Fees AJ, Colburn TD, Stabler T, Allen JD, Jones AM, Musch TI, Poole DC. Skeletal Muscle Vascular Control During Exercise: Impact of Nitrite Infusion During Nitric Oxide Synthase Inhibition in Healthy Rats. J Cardiovasc Pharmacol Ther 2015; 21:201-8. [PMID: 26272082 DOI: 10.1177/1074248415599061] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/05/2015] [Accepted: 06/17/2015] [Indexed: 12/26/2022]
Abstract
The nitric oxide synthase (NOS)-independent pathway of nitric oxide (NO) production in which nitrite (NO2 (-)) is reduced to NO may have therapeutic applications for those with cardiovascular diseases in which the NOS pathway is downregulated. We tested the hypothesis that NO2 (-) infusion would reduce mean arterial pressure (MAP) and increase skeletal muscle blood flow (BF) and vascular conductance (VC) during exercise in the face of NOS blockade via L-NAME. Following infusion of L-NAME (10 mg kg(-1), L-NAME), male Sprague-Dawley rats (3-6 months, n = 8) exercised without N(G)-nitro-L arginine methyl ester (L-NAME) and after infusion of sodium NO2 (-) (7 mg kg(-1); L-NAME + NO2 (-)). MAP and hindlimb skeletal muscle BF (radiolabeled microsphere infusions) were measured during submaximal treadmill running (20 m min(-1), 5% grade). Across group comparisons were made with a published control data set (n = 11). Relative to L-NAME, NO2 (-) infusion significantly reduced MAP (P < 0.03). The lower MAP in L-NAME+NO2 (-) was not different from healthy control animals (control: 137 ± 3 L-NAME: 157 ± 7, L-NAME + NO2 (-): 136 ± 5 mm Hg). Also, NO2 (-) infusion significantly increased VC when compared to L-NAME (P < 0.03), ultimately negating any significant differences from control animals (control: 0.78 ± 0.05, L-NAME: 0.57 ± 0.03, L-NAME + NO2 (-); 0.69 ± 0.04 mL min(-1) 100 g(-1) mm Hg(-1)) with no apparent fiber-type preferential effect. Overall, hindlimb BF was decreased significantly by L-NAME; however, in L-NAME + NO2 (-), BF improved to a level not significantly different from healthy controls (control: 108 ± 8, L-NAME: 88 ± 3, L-NAME + NO2 (-): 94 ± 6 mL min(-1) 100 g(-1), P = 0.38 L-NAME vs L-NAME + NO2 (-)). Individuals with diseases that impair NOS activity, and thus vascular function, may benefit from a NO2 (-)-based therapy in which NO bioavailability is elevated in an NOS-independent manner.
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Affiliation(s)
- Scott K Ferguson
- Department of Anatomy and Physiology, College of Veterinary Medicine, Kansas State University, Manhattan, KS, USA
| | - Angela A Glean
- Department of Kinesiology, Kansas State University, Manhattan, KS, USA
| | - Clark T Holdsworth
- Department of Anatomy and Physiology, College of Veterinary Medicine, Kansas State University, Manhattan, KS, USA
| | - Jennifer L Wright
- Department of Anatomy and Physiology, College of Veterinary Medicine, Kansas State University, Manhattan, KS, USA
| | - Alex J Fees
- Department of Anatomy and Physiology, College of Veterinary Medicine, Kansas State University, Manhattan, KS, USA
| | - Trenton D Colburn
- Department of Kinesiology, Kansas State University, Manhattan, KS, USA
| | - Thomas Stabler
- Institute of Sport Exercise and Active Living, Victoria University, Melbourne, Victoria, Australia
| | - Jason D Allen
- Institute of Sport Exercise and Active Living, Victoria University, Melbourne, Victoria, Australia
| | - Andrew M Jones
- Sport and Health Sciences, University of Exeter, St Luke's Campus, Exeter, United Kingdom
| | - Timothy I Musch
- Department of Anatomy and Physiology, College of Veterinary Medicine, Kansas State University, Manhattan, KS, USA Department of Kinesiology, Kansas State University, Manhattan, KS, USA
| | - David C Poole
- Department of Anatomy and Physiology, College of Veterinary Medicine, Kansas State University, Manhattan, KS, USA Department of Kinesiology, Kansas State University, Manhattan, KS, USA
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15
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Arif S, Borgognone A, Lin ELS, O'Sullivan AG, Sharma V, Drury NE, Menon A, Nightingale P, Mascaro J, Bonser RS, Horowitz JD, Feelisch M, Frenneaux MP, Madhani M. Role of aldehyde dehydrogenase in hypoxic vasodilator effects of nitrite in rats and humans. Br J Pharmacol 2015; 172:3341-52. [PMID: 25754766 PMCID: PMC4500370 DOI: 10.1111/bph.13122] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2014] [Revised: 02/09/2015] [Accepted: 02/27/2015] [Indexed: 12/24/2022] Open
Abstract
BACKGROUND AND PURPOSE Hypoxic conditions favour the reduction of nitrite to nitric oxide (NO) to elicit vasodilatation, but the mechanism(s) responsible for bioconversion remains ill defined. In the present study, we assess the role of aldehyde dehydrogenase 2 (ALDH2) in nitrite bioactivation under normoxia and hypoxia in the rat and human vasculature. EXPERIMENTAL APPROACH The role of ALDH2 in vascular responses to nitrite was studied using rat thoracic aorta and gluteal subcutaneous fat resistance vessels from patients with heart failure (HF; 16 patients) in vitro and by measurement of changes in forearm blood flow (FBF) during intra-arterial nitrite infusion (21 patients) in vivo. Specifically, we investigated the effects of (i) ALDH2 inhibition by cyanamide or propionaldehyde and the (ii) tolerance-independent inactivation of ALDH2 by glyceryl trinitrate (GTN) on the vasodilator activity of nitrite. In each setting, nitrite effects were measured via evaluation of the concentration-response relationship under normoxic and hypoxic conditions in the absence or presence of ALDH2 inhibitors. KEY RESULTS Both in rat aorta and human resistance vessels, dilatation to nitrite was diminished following ALDH2 inhibition, in particular under hypoxia. In humans there was a non-significant trend towards attenuation of nitrite-mediated increases in FBF. CONCLUSIONS AND IMPLICATIONS In human and rat vascular tissue in vitro, hypoxic nitrite-mediated vasodilatation involves ALDH2. In patients with HF in vivo, the role of this enzyme in nitrite bioactivation is at the most, modest, suggesting the involvement of other more important mechanisms.
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Affiliation(s)
- Sayqa Arif
- Centre for Cardiovascular Sciences, College of Medical and Dental Sciences, University of Birmingham, Birmingham, UK
| | - Alessandra Borgognone
- Centre for Cardiovascular Sciences, College of Medical and Dental Sciences, University of Birmingham, Birmingham, UK
| | - Erica Lai-Sze Lin
- Centre for Cardiovascular Sciences, College of Medical and Dental Sciences, University of Birmingham, Birmingham, UK
| | - Aine G O'Sullivan
- Centre for Cardiovascular Sciences, College of Medical and Dental Sciences, University of Birmingham, Birmingham, UK
| | - Vishal Sharma
- Department of Cardiology, Royal Liverpool University Hospital, Liverpool, UK
| | - Nigel E Drury
- Centre for Cardiovascular Sciences, College of Medical and Dental Sciences, University of Birmingham, Birmingham, UK
| | - Ashvini Menon
- Centre for Cardiovascular Sciences, College of Medical and Dental Sciences, University of Birmingham, Birmingham, UK
| | - Peter Nightingale
- Wellcome Trust Clinical Research Facility, Queen Elizabeth Hospital, Edgbaston, Birmingham, UK
| | - Jorge Mascaro
- Department of Cardiothoracic Surgery, Queen Elizabeth Hospital, University Hospitals Birmingham, Edgbaston, Birmingham, UK
| | - Robert S Bonser
- Department of Cardiothoracic Surgery, Queen Elizabeth Hospital, University Hospitals Birmingham, Edgbaston, Birmingham, UK
| | - John D Horowitz
- Basil Hetzel Institute, Queen Elizabeth Hospital, University of Adelaide, Adelaide, Australia
| | - Martin Feelisch
- Clinical and Experimental Sciences, Faculty of Medicine, University of Southampton, Southampton, UK
| | | | - Melanie Madhani
- Centre for Cardiovascular Sciences, College of Medical and Dental Sciences, University of Birmingham, Birmingham, UK
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16
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Ormerod JOM, Arif S, Mukadam M, Evans JDW, Beadle R, Fernandez BO, Bonser RS, Feelisch M, Madhani M, Frenneaux MP. Short-term intravenous sodium nitrite infusion improves cardiac and pulmonary hemodynamics in heart failure patients. Circ Heart Fail 2015; 8:565-71. [PMID: 25838311 PMCID: PMC4435579 DOI: 10.1161/circheartfailure.114.001716] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/15/2014] [Accepted: 03/25/2015] [Indexed: 11/16/2022]
Abstract
BACKGROUND Nitrite exhibits hypoxia-dependent vasodilator properties, selectively dilating capacitance vessels in healthy subjects. Unlike organic nitrates, it seems not to be subject to the development of tolerance. Currently, therapeutic options for decompensated heart failure (HF) are limited. We hypothesized that by preferentially dilating systemic capacitance and pulmonary resistance vessels although only marginally dilating resistance vessels, sodium nitrite (NaNO2) infusion would increase cardiac output but reduce systemic arterial blood pressure only modestly. We therefore undertook a first-in-human HF proof of concept/safety study, evaluating the hemodynamic effects of short-term NaNO2 infusion. METHODS AND RESULTS Twenty-five patients with severe chronic HF were recruited. Eight received short-term (5 minutes) intravenous NaNO2 at 10 μg/kg/min and 17 received 50 μg/kg/min with measurement of cardiac hemodynamics. During infusion of 50 μg/kg/min, left ventricular stroke volume increased (from 43.22±21.5 to 51.84±23.6 mL; P=0.003), with marked falls in pulmonary vascular resistance (by 29%; P=0.03) and right atrial pressure (by 40%; P=0.007), but with only modest falls in mean arterial blood pressure (by 4 mm Hg; P=0.004). The increase in stroke volume correlated with the increase in estimated trans-septal gradient (=pulmonary capillary wedge pressure-right atrial pressure; r=0.67; P=0.003), suggesting relief of diastolic ventricular interaction as a contributory mechanism. Directionally similar effects were observed for the above hemodynamic parameters with 10 μg/kg/min; this was significant only for stroke volume, not for other parameters. CONCLUSIONS This first-in-human HF efficacy/safety study demonstrates an attractive profile during short-term systemic NaNO2 infusion that may be beneficial in decompensated HF and warrants further evaluation with longer infusion regimens.
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Affiliation(s)
- Julian O M Ormerod
- From the Centre for Cardiovascular Sciences, College of Medical and Dental Sciences, University of Birmingham, Birmingham, United Kingdom (J.O.M.O., S.A., J.D.W.E., R.B., M.M.); Department of Cardiothoracic Surgery, Queen Elizabeth Hospital Birmingham NHS Trust, Birmingham, United Kingdom (M.M., R.S.B.); Clinical and Experimental Sciences, Faculty of Medicine, University of Southampton, Southampton, United Kingdom (B.O.F., M.F.); and Faculty of Medicine and Health Sciences, University of East Anglia, Norwich, United Kingdom (M.P.F.)
| | - Sayqa Arif
- From the Centre for Cardiovascular Sciences, College of Medical and Dental Sciences, University of Birmingham, Birmingham, United Kingdom (J.O.M.O., S.A., J.D.W.E., R.B., M.M.); Department of Cardiothoracic Surgery, Queen Elizabeth Hospital Birmingham NHS Trust, Birmingham, United Kingdom (M.M., R.S.B.); Clinical and Experimental Sciences, Faculty of Medicine, University of Southampton, Southampton, United Kingdom (B.O.F., M.F.); and Faculty of Medicine and Health Sciences, University of East Anglia, Norwich, United Kingdom (M.P.F.)
| | - Majid Mukadam
- From the Centre for Cardiovascular Sciences, College of Medical and Dental Sciences, University of Birmingham, Birmingham, United Kingdom (J.O.M.O., S.A., J.D.W.E., R.B., M.M.); Department of Cardiothoracic Surgery, Queen Elizabeth Hospital Birmingham NHS Trust, Birmingham, United Kingdom (M.M., R.S.B.); Clinical and Experimental Sciences, Faculty of Medicine, University of Southampton, Southampton, United Kingdom (B.O.F., M.F.); and Faculty of Medicine and Health Sciences, University of East Anglia, Norwich, United Kingdom (M.P.F.)
| | - Jonathan D W Evans
- From the Centre for Cardiovascular Sciences, College of Medical and Dental Sciences, University of Birmingham, Birmingham, United Kingdom (J.O.M.O., S.A., J.D.W.E., R.B., M.M.); Department of Cardiothoracic Surgery, Queen Elizabeth Hospital Birmingham NHS Trust, Birmingham, United Kingdom (M.M., R.S.B.); Clinical and Experimental Sciences, Faculty of Medicine, University of Southampton, Southampton, United Kingdom (B.O.F., M.F.); and Faculty of Medicine and Health Sciences, University of East Anglia, Norwich, United Kingdom (M.P.F.)
| | - Roger Beadle
- From the Centre for Cardiovascular Sciences, College of Medical and Dental Sciences, University of Birmingham, Birmingham, United Kingdom (J.O.M.O., S.A., J.D.W.E., R.B., M.M.); Department of Cardiothoracic Surgery, Queen Elizabeth Hospital Birmingham NHS Trust, Birmingham, United Kingdom (M.M., R.S.B.); Clinical and Experimental Sciences, Faculty of Medicine, University of Southampton, Southampton, United Kingdom (B.O.F., M.F.); and Faculty of Medicine and Health Sciences, University of East Anglia, Norwich, United Kingdom (M.P.F.)
| | - Bernadette O Fernandez
- From the Centre for Cardiovascular Sciences, College of Medical and Dental Sciences, University of Birmingham, Birmingham, United Kingdom (J.O.M.O., S.A., J.D.W.E., R.B., M.M.); Department of Cardiothoracic Surgery, Queen Elizabeth Hospital Birmingham NHS Trust, Birmingham, United Kingdom (M.M., R.S.B.); Clinical and Experimental Sciences, Faculty of Medicine, University of Southampton, Southampton, United Kingdom (B.O.F., M.F.); and Faculty of Medicine and Health Sciences, University of East Anglia, Norwich, United Kingdom (M.P.F.)
| | - Robert S Bonser
- From the Centre for Cardiovascular Sciences, College of Medical and Dental Sciences, University of Birmingham, Birmingham, United Kingdom (J.O.M.O., S.A., J.D.W.E., R.B., M.M.); Department of Cardiothoracic Surgery, Queen Elizabeth Hospital Birmingham NHS Trust, Birmingham, United Kingdom (M.M., R.S.B.); Clinical and Experimental Sciences, Faculty of Medicine, University of Southampton, Southampton, United Kingdom (B.O.F., M.F.); and Faculty of Medicine and Health Sciences, University of East Anglia, Norwich, United Kingdom (M.P.F.)
| | - Martin Feelisch
- From the Centre for Cardiovascular Sciences, College of Medical and Dental Sciences, University of Birmingham, Birmingham, United Kingdom (J.O.M.O., S.A., J.D.W.E., R.B., M.M.); Department of Cardiothoracic Surgery, Queen Elizabeth Hospital Birmingham NHS Trust, Birmingham, United Kingdom (M.M., R.S.B.); Clinical and Experimental Sciences, Faculty of Medicine, University of Southampton, Southampton, United Kingdom (B.O.F., M.F.); and Faculty of Medicine and Health Sciences, University of East Anglia, Norwich, United Kingdom (M.P.F.)
| | - Melanie Madhani
- From the Centre for Cardiovascular Sciences, College of Medical and Dental Sciences, University of Birmingham, Birmingham, United Kingdom (J.O.M.O., S.A., J.D.W.E., R.B., M.M.); Department of Cardiothoracic Surgery, Queen Elizabeth Hospital Birmingham NHS Trust, Birmingham, United Kingdom (M.M., R.S.B.); Clinical and Experimental Sciences, Faculty of Medicine, University of Southampton, Southampton, United Kingdom (B.O.F., M.F.); and Faculty of Medicine and Health Sciences, University of East Anglia, Norwich, United Kingdom (M.P.F.)
| | - Michael P Frenneaux
- From the Centre for Cardiovascular Sciences, College of Medical and Dental Sciences, University of Birmingham, Birmingham, United Kingdom (J.O.M.O., S.A., J.D.W.E., R.B., M.M.); Department of Cardiothoracic Surgery, Queen Elizabeth Hospital Birmingham NHS Trust, Birmingham, United Kingdom (M.M., R.S.B.); Clinical and Experimental Sciences, Faculty of Medicine, University of Southampton, Southampton, United Kingdom (B.O.F., M.F.); and Faculty of Medicine and Health Sciences, University of East Anglia, Norwich, United Kingdom (M.P.F.).
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17
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Bailey JC, Feelisch M, Horowitz JD, Frenneaux MP, Madhani M. Pharmacology and therapeutic role of inorganic nitrite and nitrate in vasodilatation. Pharmacol Ther 2014; 144:303-20. [PMID: 24992304 DOI: 10.1016/j.pharmthera.2014.06.009] [Citation(s) in RCA: 43] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2014] [Accepted: 06/25/2014] [Indexed: 02/07/2023]
Abstract
Nitrite has emerged as an important bioactive molecule that can be biotransformed to nitric oxide (NO) related metabolites in normoxia and reduced to NO under hypoxic and acidic conditions to exert vasodilatory effects and confer a variety of other benefits to the cardiovascular system. Abundant research is currently underway to understand the mechanisms involved and define the role of nitrite in health and disease. In this review we discuss the impact of nitrite and dietary nitrate on vascular function and the potential therapeutic role of nitrite in acute heart failure.
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Affiliation(s)
- J C Bailey
- Centre for Cardiovascular Sciences, College of Medical and Dental Sciences, University of Birmingham, UK
| | - M Feelisch
- Clinical and Experimental Sciences, Faculty of Medicine, University of Southampton, Southampton, UK
| | - J D Horowitz
- The Queen Elizabeth Hospital, Adelaide, Australia
| | - M P Frenneaux
- School of Medicine and Dentistry, University of Aberdeen, Aberdeen, UK
| | - M Madhani
- Centre for Cardiovascular Sciences, College of Medical and Dental Sciences, University of Birmingham, UK.
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18
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Hypoxic potentiation of nitrite effects in human vessels and platelets. Nitric Oxide 2014; 40:36-44. [PMID: 24858215 DOI: 10.1016/j.niox.2014.05.005] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2014] [Revised: 05/13/2014] [Accepted: 05/15/2014] [Indexed: 11/22/2022]
Abstract
Previous studies in non-human blood vessels and in platelets have demonstrated that under hypoxic conditions release of NO from nitrite (NO2(-)) is potentiated by deoxyhaemoglobin. In the current study, we characterized hypoxic potentiation of NO2(-) effects in human vasculature and platelets in vitro, addressing underlying mechanisms. The vasodilator efficacy of NO2(-), in comparison with glyceryl trinitrate (GTN), was evaluated in vitro, using segments of human saphenous vein. Under hypoxic conditions, there was a leftward shift of the NO2(-) concentration-response curve (EC50: 22 μM in hyperoxia vs 3.5 μM in hypoxia; p<0.01), but no significant potentiation of GTN effect. In the presence of red blood cells, hypoxic potentiation of NO2(-) vasodilator effect was accentuated. In whole blood samples and platelet-rich plasma (PRP) we assessed inhibition of platelet aggregation by NO2(-) (1mM), in comparison with that of sodium nitroprusside (SNP, 10 μM). In individual subjects (n=37), there was a strong correlation (r=0.75, p<0.0001) between anti-aggregatory effects of NO2(-) and SNP in whole blood, signifying that resultant sGC activation underlies biological effect and responses to NO2(-) are diminished in the presence of NO resistance. In PRP, the effects of NO2(-) were less pronounced than in whole blood (p=0.0001), suggesting an important role of Hb (within RBCs) in the bioconversion of NO2(-) to NO. Inhibition of platelet aggregation by NO2(-) was almost 3-fold greater in venous than in arterial blood (p<0.0001), and deoxyHb concentration directly correlated (r=0.69, p=0.013) with anti-aggregatory response. Incremental hypoxia applied to venous blood samples (in hypoxic chamber) caused a progressive increase in both deoxyHb level and anti-aggregatory effect of NO2(-). When subjects inhaled a 12% O2 mixture for 20 min, there was a 3-fold rise in blood deoxyHb fraction (p<0.01). In PRP, response to NO2(-) also increased under hypoxia, and was further enhanced (p<0.01) by deoxyHb. Furthermore, deoxyHb exerted significant anti-aggregatory effects even in the absence of added NO2(-), suggesting a role for endogenous NO2(-). The results of this work provide further mechanistic insights into hypoxic potentiation of vasodilator and anti-aggregatory actions of NO2(-). In human saphenous veins and blood, the balance of evidence suggests differential rates of NO release from NO2(-) (largely modulated by deoxyHb) as the fundamental mechanism.
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19
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Sindler AL, Devan AE, Fleenor BS, Seals DR. Inorganic nitrite supplementation for healthy arterial aging. J Appl Physiol (1985) 2014; 116:463-77. [PMID: 24408999 PMCID: PMC3949212 DOI: 10.1152/japplphysiol.01100.2013] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2013] [Accepted: 01/03/2014] [Indexed: 12/12/2022] Open
Abstract
Aging is the major risk factor for cardiovascular diseases (CVD). This is attributable primarily to adverse changes in arteries, notably, increases in large elastic artery stiffness and endothelial dysfunction mediated by inadequate concentrations of the vascular-protective molecule, nitric oxide (NO), and higher levels of oxidative stress and inflammation. Inorganic nitrite is a promising precursor molecule for augmenting circulating and tissue NO bioavailability because it requires only a one-step reduction to NO. Nitrite also acts as an independent signaling molecule, exerting many of the effects previously attributed to NO. Results of recent studies indicate that nitrite may be effective in the treatment of vascular aging. In old mice, short-term oral sodium nitrite supplementation reduces aortic pulse wave velocity, the gold-standard measure of large elastic artery stiffness, and ameliorates endothelial dysfunction, as indicated by normalization of NO-mediated endothelium-dependent dilation. These improvements in age-related vascular dysfunction with nitrite are mediated by reductions in oxidative stress and inflammation, and may be linked to increases in mitochondrial biogenesis and health. Increasing nitrite levels via dietary intake of nitrate appears to have similarly beneficial effects in many of the same physiological and clinical settings. Several clinical trials are being performed to determine the broad therapeutic potential of increasing nitrite bioavailability on human health and disease, including studies related to vascular aging. In summary, inorganic nitrite, as well as dietary nitrate supplementation, represents a promising therapy for treatment of arterial aging and prevention of age-associated CVD in humans.
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Affiliation(s)
- Amy L Sindler
- Department of Integrative Physiology, University of Colorado Boulder, Boulder, Colorado
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20
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Dautov RF, Ngo DTM, Licari G, Liu S, Sverdlov AL, Ritchie RH, Kemp-Harper BK, Horowitz JD, Chirkov YY. The nitric oxide redox sibling nitroxyl partially circumvents impairment of platelet nitric oxide responsiveness. Nitric Oxide 2013; 35:72-8. [PMID: 24012721 DOI: 10.1016/j.niox.2013.08.006] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2013] [Revised: 08/21/2013] [Accepted: 08/28/2013] [Indexed: 01/17/2023]
Abstract
Impaired platelet responsiveness to nitric oxide (NO resistance) is a common characteristic of many cardiovascular disease states and represents an independent risk factor for cardiac events and mortality. NO resistance reflects both scavenging of NO by superoxide (O2(-)), and impairment of the NO receptor, soluble guanylate cyclase (sGC). There is thus an urgent need for circumvention of NO resistance in order to improve clinical outcomes. Nitroxyl (HNO), like NO, produces vasodilator and anti-aggregatory effects, largely via sGC activation, but is not inactivated by O2(-). We tested the hypothesis that HNO circumvents NO resistance in human platelets. In 57 subjects with or without ischemic heart disease, platelet responses to the HNO donor isopropylamine NONOate (IPA/NO) and the NO donor sodium nitroprusside (SNP) were compared. While SNP (10μM) induced 29±3% (p<0.001) inhibition of platelet aggregation, IPA/NO (10μM) caused 75±4% inhibition (p<0.001). In NO-resistant subjects (n=28), the IPA/NO:SNP response ratio was markedly increased (p<0.01), consistent with partial circumvention of NO resistance. Similarly, cGMP accumulation in platelets was greater (p<0.001) with IPA/NO than with SNP stimulation. The NO scavenger carboxy-PTIO (CPTIO, 200μM) inhibited SNP and IPA/NO responses by 92±7% and 17±4% respectively (p<0.001 for differential inhibition), suggesting that effects of IPA/NO are only partially NO-mediated. ODQ (10μM) inhibited IPA/NO responses by 36±8% (p<0.001), consistent with a contribution of sGC/haem to IPA/NO inhibition of aggregation. There was no significant relationship between whole blood ROS content and IPA/NO responses. Thus the HNO donor IPA/NO substantially circumvents platelet NO resistance while acting, at least partially, as a haem-mediated sGC activator.
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Affiliation(s)
- R F Dautov
- Cardiology Unit, Basil Hetzel Institute, The Queen Elizabeth Hospital, University of Adelaide, Woodville, Australia.
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