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Hofmaenner DA, Singer M. Challenging management dogma where evidence is non-existent, weak or outdated. Intensive Care Med 2022; 48:548-558. [PMID: 35303116 PMCID: PMC8931587 DOI: 10.1007/s00134-022-06659-4] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2022] [Accepted: 02/25/2022] [Indexed: 12/19/2022]
Abstract
Medical practice is dogged by dogma. A conclusive evidence base is lacking for many aspects of patient management. Clinicians, therefore, rely upon engrained treatment strategies as the dogma seems to work, or at least is assumed to do so. Evidence is often distorted, overlooked or misapplied in the re-telling. However, it is incorporated as fact in textbooks, policies, guidelines and protocols with resource and medicolegal implications. We provide here four examples of medical dogma that underline the above points: loop diuretic treatment for acute heart failure; the effectiveness of heparin thromboprophylaxis; the rate of sodium correction for hyponatraemia; and the mantra of "each hour counts" for treating meningitis. It is notable that the underpinning evidence is largely unsupportive of these doctrines. We do not necessarily advocate change, but rather encourage critical reflection on current practices and the need for prospective studies.
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Affiliation(s)
- Daniel A Hofmaenner
- Bloomsbury Institute of Intensive Care Medicine, Division of Medicine, University College London, Cruciform Building, Gower St, London, WC1 6BT, UK
| | - Mervyn Singer
- Bloomsbury Institute of Intensive Care Medicine, Division of Medicine, University College London, Cruciform Building, Gower St, London, WC1 6BT, UK.
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2
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Reddy YNV, Stewart GM, Obokata M, Koepp KE, Borlaug BA. Peripheral and pulmonary effects of inorganic nitrite during exercise in heart failure with preserved ejection fraction. Eur J Heart Fail 2021; 23:814-823. [PMID: 33421267 DOI: 10.1002/ejhf.2093] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/21/2020] [Revised: 12/01/2020] [Accepted: 01/01/2021] [Indexed: 01/06/2023] Open
Abstract
AIMS To determine whether inorganic nitrite improves peripheral and pulmonary oxygen (O2 ) transport during exercise in heart failure with preserved ejection fraction (HFpEF). METHODS AND RESULTS Data from two invasive, randomized, double-blind, placebo-controlled trials with matched workload exercise of inhaled and intravenous sodium nitrite were pooled for this analysis (n = 51). Directly measured O2 consumption (VO2 ) and blood gas data were used to evaluate the effect of nitrite on skeletal muscle O2 conductance (Dm), VO2 kinetics, alveolar capillary membrane O2 conductance (DL ), and O2 utilization during submaximal exercise. As compared to placebo, treatment with nitrite resulted in an improvement in Dm (+4.9 ± 6.5 vs. -0.9 ± 4.3 mL/mmHg*min, P = 0.0008) as well as VO2 kinetics measured by mean response time (-5.0 ± 6.9 vs. -0.6 ± 6.0 s, P = 0.03), with preserved O2 utilization despite increased convective O2 delivery through cardiac output (+0.4 ± 0.7 vs. -0.3 ± 0.9 L/min, P = 0.02). Nitrite improved DL (+2.5 ± 6.3 vs. -2.0 ± 9.0 mL/mmHg*min, P = 0.05) with exercise, which was associated with lower pulmonary capillary pressures (r = -0.34, P = 0.02), and reduced pulmonary dead space ventilation fraction (-0.01 ± 0.05 vs. +0.02 ± 0.05, P = 0.02). CONCLUSION Sodium nitrite enhances skeletal muscle Dm during exercise as well as pulmonary O2 diffusion, optimizing O2 kinetics in tandem with increased convective O2 delivery through cardiac output augmentation. The favourable combined pulmonary, cardiac and peripheral effects of nitrite may improve exercise tolerance in people with HFpEF and requires further investigation. CLINICAL TRIAL REGISTRATION ClinicalTrials.gov ID NCT01932606 and NCT02262078.
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Affiliation(s)
- Yogesh N V Reddy
- Department of Cardiovascular Medicine, Mayo Clinic, Rochester, MN, USA
| | - Glenn M Stewart
- Department of Cardiovascular Medicine, Mayo Clinic, Rochester, MN, USA
| | - Masaru Obokata
- Department of Cardiovascular Medicine, Mayo Clinic, Rochester, MN, USA
| | - Katlyn E Koepp
- Department of Cardiovascular Medicine, Mayo Clinic, Rochester, MN, USA
| | - Barry A Borlaug
- Department of Cardiovascular Medicine, Mayo Clinic, Rochester, MN, USA
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3
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Chen J, Hamm LL, Bundy JD, Kumbala DR, Bodana S, Chandra S, Chen CS, Starcke CC, Guo Y, Schaefer CM, Lustigova E, Mahone E, Vadalia AM, Livingston T, Obst K, Hernandez J, Bokhari SR, Kleinpeter M, Alper AB, Lukitsch I, He H, Nieman DC, He J. Combination Treatment with Sodium Nitrite and Isoquercetin on Endothelial Dysfunction among Patients with CKD: A Randomized Phase 2 Pilot Trial. Clin J Am Soc Nephrol 2020; 15:1566-1575. [PMID: 33023894 PMCID: PMC7646238 DOI: 10.2215/cjn.02020220] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2020] [Accepted: 08/28/2020] [Indexed: 01/04/2023]
Abstract
BACKGROUND AND OBJECTIVES Endothelial dysfunction is common among patients with CKD. We tested the efficacy and safety of combination treatment with sodium nitrite and isoquercetin on biomarkers of endothelial dysfunction in patients with CKD. DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS This randomized, double-blind, placebo-controlled phase 2 pilot trial enrolled 70 patients with predialysis CKD. Thirty-five were randomly assigned to combination treatment with sodium nitrite (40 mg twice daily) and isoquercetin (225 mg once daily) for 12 weeks, and 35 were randomly assigned to placebo. The primary outcome was mean change in flow-mediated vasodilation over the 12-week intervention. Secondary and safety outcomes included biomarkers of endothelial dysfunction, inflammation, and oxidative stress as well as kidney function, methemoglobin, and adverse events. Intention-to-treat analysis was conducted. RESULTS Baseline characteristics, including age, sex, race, cigarette smoking, history of hypertension and diabetes, use of renin-angiotensin system blockers, BP, fasting glucose, lipid profile, kidney function, urine albumin-creatinine ratio, and endothelial biomarkers, were comparable between groups. Over the 12-week intervention, flow-mediated vasodilation increased 1.1% (95% confidence interval, -0.1 to 2.3) in the treatment group and 0.3% (95% confidence interval, -0.9 to 1.5) in the placebo group, and net change was 0.8% (95% confidence interval, -0.9 to 2.5). In addition, changes in biomarkers of endothelial dysfunction (vascular adhesion molecule-1, intercellular adhesion molecule-1, E-selectin, vWf, endostatin, and asymmetric dimethylarginine), inflammation (TNF-α, IL-6, C-reactive protein, IL-1 receptor antagonist, and monocyte chemoattractant protein-1), and oxidative stress (oxidized LDL and nitrotyrosines) were not significantly different between the two groups. Furthermore, changes in eGFR, urine albumin-creatinine ratio, methemoglobin, and adverse events were not significantly different between groups. CONCLUSIONS This randomized phase 2 pilot trial suggests that combination treatment with sodium nitrite and isoquercetin did not significantly improve flow-mediated vasodilation or other endothelial function biomarkers but also did not increase adverse events compared with placebo among patients with CKD. CLINICAL TRIAL REGISTRY NAME AND REGISTRATION NUMBER Nitrite, Isoquercetin, and Endothelial Dysfunction (NICE), NCT02552888.
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Affiliation(s)
- Jing Chen
- Department of Medicine, Tulane University School of Medicine, New Orleans, Louisiana .,Department of Epidemiology, Tulane University School of Public Health and Tropical Medicine, New Orleans, Louisiana.,Tulane University Translational Science Institute, New Orleans, Louisiana.,Department of Medicine, Southeast Louisiana Veterans Health Care System, New Orleans, Louisiana
| | - L Lee Hamm
- Department of Medicine, Tulane University School of Medicine, New Orleans, Louisiana.,Tulane University Translational Science Institute, New Orleans, Louisiana
| | - Joshua D Bundy
- Department of Epidemiology, Tulane University School of Public Health and Tropical Medicine, New Orleans, Louisiana.,Tulane University Translational Science Institute, New Orleans, Louisiana
| | | | - Shirisha Bodana
- Department of Nephrology, Ochsner Health System, New Orleans, Louisiana
| | - Sehgal Chandra
- Department of Radiology, University of Pennsylvania Perelman School of Medicine, Philadelphia, Pennsylvania
| | - Chung-Shiuan Chen
- Department of Epidemiology, Tulane University School of Public Health and Tropical Medicine, New Orleans, Louisiana .,Tulane University Translational Science Institute, New Orleans, Louisiana
| | - Charlton C Starcke
- Department of Epidemiology, Tulane University School of Public Health and Tropical Medicine, New Orleans, Louisiana.,Tulane University Translational Science Institute, New Orleans, Louisiana
| | - Yajun Guo
- Department of Epidemiology, Tulane University School of Public Health and Tropical Medicine, New Orleans, Louisiana
| | - Caroline M Schaefer
- Department of Epidemiology, Tulane University School of Public Health and Tropical Medicine, New Orleans, Louisiana
| | - Eva Lustigova
- Department of Epidemiology, Tulane University School of Public Health and Tropical Medicine, New Orleans, Louisiana
| | - Erin Mahone
- Department of Epidemiology, Tulane University School of Public Health and Tropical Medicine, New Orleans, Louisiana.,Tulane University Translational Science Institute, New Orleans, Louisiana
| | - Aarti M Vadalia
- Department of Epidemiology, Tulane University School of Public Health and Tropical Medicine, New Orleans, Louisiana.,Tulane University Translational Science Institute, New Orleans, Louisiana
| | - Terra Livingston
- Department of Epidemiology, Tulane University School of Public Health and Tropical Medicine, New Orleans, Louisiana.,Tulane University Translational Science Institute, New Orleans, Louisiana
| | - Katherine Obst
- Department of Epidemiology, Tulane University School of Public Health and Tropical Medicine, New Orleans, Louisiana.,Tulane University Translational Science Institute, New Orleans, Louisiana
| | - Jesus Hernandez
- Department of Medicine, Tulane University School of Medicine, New Orleans, Louisiana
| | - Syed Rizwan Bokhari
- Department of Medicine, Tulane University School of Medicine, New Orleans, Louisiana
| | - Myra Kleinpeter
- Department of Medicine, Tulane University School of Medicine, New Orleans, Louisiana
| | - Arnold B Alper
- Department of Medicine, Tulane University School of Medicine, New Orleans, Louisiana
| | - Ivo Lukitsch
- Department of Nephrology, Ochsner Health System, New Orleans, Louisiana
| | - Hua He
- Department of Epidemiology, Tulane University School of Public Health and Tropical Medicine, New Orleans, Louisiana .,Tulane University Translational Science Institute, New Orleans, Louisiana
| | - David C Nieman
- Human Performance Lab, Appalachian State University, Kannapolis, North Carolina
| | - Jiang He
- Department of Medicine, Tulane University School of Medicine, New Orleans, Louisiana .,Department of Epidemiology, Tulane University School of Public Health and Tropical Medicine, New Orleans, Louisiana.,Tulane University Translational Science Institute, New Orleans, Louisiana
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4
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Parasuraman SK, Loudon BL, Lowery C, Cameron D, Singh S, Schwarz K, Gollop ND, Rudd A, McKiddie F, Phillips JJ, Prasad SK, Wilson AM, Sen-Chowdhry S, Clark A, Vassiliou VS, Dawson DK, Frenneaux MP. Diastolic Ventricular Interaction in Heart Failure With Preserved Ejection Fraction. J Am Heart Assoc 2020; 8:e010114. [PMID: 30922153 PMCID: PMC6509705 DOI: 10.1161/jaha.118.010114] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Background Exercise‐induced pulmonary hypertension is common in heart failure with preserved ejection fraction (HFpEF). We hypothesized that this could result in pericardial constraint and diastolic ventricular interaction in some patients during exercise. Methods and Results Contrast stress echocardiography was performed in 30 HFpEF patients, 17 hypertensive controls, and 17 normotensive controls (healthy). Cardiac volumes, and normalized radius of curvature (NRC) of the interventricular septum at end‐diastole and end‐systole, were measured at rest and peak‐exercise, and compared between the groups. The septum was circular at rest in all 3 groups at end‐diastole. At peak‐exercise, end‐systolic NRC increased to 1.47±0.05 (P<0.001) in HFpEF patients, confirming development of pulmonary hypertension. End‐diastolic NRC also increased to 1.54±0.07 (P<0.001) in HFpEF patients, indicating septal flattening, and this correlated significantly with end‐systolic NRC (ρ=0.51, P=0.007). In hypertensive controls and healthy controls, peak‐exercise end‐systolic NRC increased, but this was significantly less than observed in HFpEF patients (HFpEF, P=0.02 versus hypertensive controls; P<0.001 versus healthy). There were also small, non‐significant increases in end‐diastolic NRC in both groups (hypertensive controls, +0.17±0.05, P=0.38; healthy, +0.06±0.03, P=0.93). In HFpEF patients, peak‐exercise end‐diastolic NRC also negatively correlated (r=−0.40, P<0.05) with the change in left ventricular end‐diastolic volume with exercise (ie, the Frank‐Starling mechanism), and a trend was noted towards a negative correlation with change in stroke volume (r=−0.36, P=0.08). Conclusions Exercise pulmonary hypertension causes substantial diastolic ventricular interaction on exercise in some patients with HFpEF, and this restriction to left ventricular filling by the right ventricle exacerbates the pre‐existing impaired Frank‐Starling response in these patients.
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Affiliation(s)
| | - Brodie L Loudon
- 1 Norwich Medical School University of East Anglia Norwich United Kingdom
| | - Crystal Lowery
- 1 Norwich Medical School University of East Anglia Norwich United Kingdom
| | - Donnie Cameron
- 1 Norwich Medical School University of East Anglia Norwich United Kingdom
| | | | | | - Nicholas D Gollop
- 1 Norwich Medical School University of East Anglia Norwich United Kingdom
| | - Amelia Rudd
- 4 Department of Cardiology School of Medicine & Dentistry University of Aberdeen United Kingdom
| | - Fergus McKiddie
- 5 Nuclear Medicine Aberdeen Royal Infirmary NHS Grampian Aberdeen United Kingdom
| | - Jim J Phillips
- 5 Nuclear Medicine Aberdeen Royal Infirmary NHS Grampian Aberdeen United Kingdom
| | - Sanjay K Prasad
- 6 Royal Brompton Hospital and Imperial College London London United Kingdom
| | - Andrew M Wilson
- 1 Norwich Medical School University of East Anglia Norwich United Kingdom
| | - Srijita Sen-Chowdhry
- 7 Institute of Cardiovascular Science University College London London United Kingdom
| | - Allan Clark
- 1 Norwich Medical School University of East Anglia Norwich United Kingdom
| | | | - Dana K Dawson
- 4 Department of Cardiology School of Medicine & Dentistry University of Aberdeen United Kingdom
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5
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Kapil V, Khambata RS, Jones DA, Rathod K, Primus C, Massimo G, Fukuto JM, Ahluwalia A. The Noncanonical Pathway for In Vivo Nitric Oxide Generation: The Nitrate-Nitrite-Nitric Oxide Pathway. Pharmacol Rev 2020; 72:692-766. [DOI: 10.1124/pr.120.019240] [Citation(s) in RCA: 69] [Impact Index Per Article: 17.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
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6
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Ntessalen M, Procter NEK, Schwarz K, Loudon BL, Minnion M, Fernandez BO, Vassiliou VS, Vauzour D, Madhani M, Constantin‐Teodosiu D, Horowitz JD, Feelisch M, Dawson D, Crichton PG, Frenneaux MP. Inorganic nitrate and nitrite supplementation fails to improve skeletal muscle mitochondrial efficiency in mice and humans. Am J Clin Nutr 2020; 111:79-89. [PMID: 31599928 PMCID: PMC6944528 DOI: 10.1093/ajcn/nqz245] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2019] [Accepted: 09/03/2019] [Indexed: 01/06/2023] Open
Abstract
BACKGROUND Inorganic nitrate, abundant in leafy green vegetables and beetroot, is thought to have protective health benefits. Adherence to a Mediterranean diet reduces the incidence and severity of coronary artery disease, whereas supplementation with nitrate can improve submaximal exercise performance. Once ingested, oral commensal bacteria may reduce nitrate to nitrite, which may subsequently be reduced to nitric oxide during conditions of hypoxia and in the presence of "nitrite reductases" such as heme- and molybdenum-containing enzymes. OBJECTIVE We aimed to explore the putative effects of inorganic nitrate and nitrite on mitochondrial function in skeletal muscle. METHODS Mice were subjected to a nitrate/nitrite-depleted diet for 2 wk, then supplemented with sodium nitrate, sodium nitrite, or sodium chloride (1 g/L) in drinking water ad libitum for 7 d before killing. Skeletal muscle mitochondrial function and expression of uncoupling protein (UCP) 3, ADP/ATP carrier protein (AAC) 1 and AAC2, and pyruvate dehydrogenase (PDH) were assessed by respirometry and Western blotting. Studies were also undertaken in human skeletal muscle biopsies from a cohort of coronary artery bypass graft patients treated with either sodium nitrite (30-min infusion of 10 μmol/min) or vehicle [0.9% (wt:vol) saline] 24 h before surgery. RESULTS Neither sodium nitrate nor sodium nitrite supplementation altered mitochondrial coupling efficiency in murine skeletal muscle, and expression of UCP3, AAC1, or AAC2, and PDH phosphorylation status did not differ between the nitrite and saline groups. Similar results were observed in human samples. CONCLUSIONS Sodium nitrite failed to improve mitochondrial metabolic efficiency, rendering this mechanism implausible for the purported exercise benefits of dietary nitrate supplementation. This trial was registered at clinicaltrials.gov as NCT04001283.
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Affiliation(s)
- Maria Ntessalen
- Institute of Medical Sciences, University of Aberdeen, Aberdeen, United Kingdom
| | - Nathan E K Procter
- Norwich Medical School, University of East Anglia, Norwich, United Kingdom
| | - Konstantin Schwarz
- Institute of Medical Sciences, University of Aberdeen, Aberdeen, United Kingdom
| | - Brodie L Loudon
- Norwich Medical School, University of East Anglia, Norwich, United Kingdom
| | - Magdalena Minnion
- Clinical & Experimental Sciences, Faculty of Medicine, University of Southampton, Southampton General Hospital, Southampton, United Kingdom
| | - Bernadette O Fernandez
- Clinical & Experimental Sciences, Faculty of Medicine, University of Southampton, Southampton General Hospital, Southampton, United Kingdom
| | | | - David Vauzour
- Norwich Medical School, University of East Anglia, Norwich, United Kingdom
| | - Melanie Madhani
- Institute of Cardiovascular Sciences, University of Birmingham, Birmingham, United Kingdom
| | - Dumitru Constantin‐Teodosiu
- Medical Research Council/Arthritis Research UK Centre for Musculoskeletal Ageing Research, National Institute for Health Research Nottingham Biomedical Research Centre, School of Life Sciences, Nottingham University Medical School, Nottingham, United Kingdom
| | - John D Horowitz
- Department of Cardiology, The Queen Elizabeth Hospital, University of Adelaide, Adelaide, South Australia, Australia
| | - Martin Feelisch
- Clinical & Experimental Sciences, Faculty of Medicine, University of Southampton, Southampton General Hospital, Southampton, United Kingdom
| | - Dana Dawson
- Department of Cardiology, School of Medicine & Dentistry, University of Aberdeen, Aberdeen, United Kingdom
| | - Paul G Crichton
- Norwich Medical School, University of East Anglia, Norwich, United Kingdom
| | - Michael P Frenneaux
- Institute of Medical Sciences, University of Aberdeen, Aberdeen, United Kingdom,Norwich Medical School, University of East Anglia, Norwich, United Kingdom,Address correspondence to MPF (E-mail: )
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7
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Uray T, Empey PE, Drabek T, Stezoski JP, Janesko-Feldman K, Jackson T, Garman RH, Kim F, Kochanek PM, Dezfulian C. Nitrite pharmacokinetics, safety and efficacy after experimental ventricular fibrillation cardiac arrest. Nitric Oxide 2019; 93:71-77. [PMID: 31526855 DOI: 10.1016/j.niox.2019.09.003] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2019] [Revised: 07/12/2019] [Accepted: 09/10/2019] [Indexed: 12/13/2022]
Abstract
INTRODUCTION Besides therapeutic hypothermia or targeted temperature management no novel therapies have been developed to improve outcomes of patients after cardiac arrest (CA). Recent studies suggest that nitrite reduces neurological damage after asphyxial CA. Nitrite is also implicated as a new mediator of remote post conditioning produced by tourniquet inflation-deflation, which is under active investigation in CA. However, little is known about brain penetration or pharmacokinetics (PK). Therefore, to define the optimal use of this agent, studies on the PK of nitrite in experimental ventricular fibrillation (VF) are needed. We tested the hypothesis that nitrite administered after resuscitation from VF is detectable in cerebrospinal fluid (CSF), brain and other organ tissues, produces no adverse hemodynamic effects, and improves neurologic outcome in rats. METHODS After return of spontaneous circulation (ROSC) of 5 min untreated VF, adult male Sprague-Dawley rats were given intravenous nitrite (8 μM, 0.13 mg/kg) or placebo as a 5 min infusion beginning at 5 min after CA. Additionally, sham groups with and without nitrite treatment were also studied. Whole blood nitrite levels were serially measured. After 15 min, CSF, brain, heart and liver tissue were collected. In a second series, using a randomized and blinded treatment protocol, rats were treated with nitrite or placebo after arrest. Neurological deficit scoring (NDS) was performed daily and eight days after resuscitation, fear conditioning testing (FCT) and brain histology were assessed. RESULTS In an initial series of experiments, rats (n = 21) were randomized to 4 groups: VF-CPR and nitrite therapy (n = 6), VF-CPR and placebo therapy (n = 5), sham (n = 5), or sham plus nitrite therapy (n = 5). Whole blood nitrite levels increased during drug infusion to 57.14 ± 10.82 μM at 11 min post-resuscitation time (1 min after dose completion) in the VF nitrite group vs. 0.94 ± 0.58 μM in the VF placebo group (p < 0.001). There was a significant difference between the treatment and placebo groups in nitrite levels in blood between 7.5 and 15 min after CPR start and between groups with respect to nitrite levels in CSF, brain, heart and liver. In a second series (n = 25 including 5 shams), 19 out of 20 animals survived until day 8. However, NDS, FCT and brain histology did not show any statistically significant difference between groups. CONCLUSIONS Nitrite, administered early after ROSC from VF, was shown to cross the blood brain barrier after a 5 min VF cardiac arrest. We characterized the PK of intravenous nitrite administration after VF and were able to demonstrate nitrite safety in this feasibility study.
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Affiliation(s)
- Thomas Uray
- Safar Center for Resuscitation Research, University of Pittsburgh School of Medicine, PA, USA; Department of Critical Care Medicine, University of Pittsburgh School of Medicine, PA, USA; Department of Emergency Medicine, Medical University of Vienna, Austria
| | - Philip E Empey
- Safar Center for Resuscitation Research, University of Pittsburgh School of Medicine, PA, USA; Department of Pharmacy and Therapeutics, University of Pittsburgh, PA, USA
| | - Tomas Drabek
- Safar Center for Resuscitation Research, University of Pittsburgh School of Medicine, PA, USA; Department of Anesthesiology, University of Pittsburgh School of Medicine, PA, USA
| | - Jason P Stezoski
- Safar Center for Resuscitation Research, University of Pittsburgh School of Medicine, PA, USA; Department of Critical Care Medicine, University of Pittsburgh School of Medicine, PA, USA
| | - Keri Janesko-Feldman
- Safar Center for Resuscitation Research, University of Pittsburgh School of Medicine, PA, USA
| | - Travis Jackson
- Safar Center for Resuscitation Research, University of Pittsburgh School of Medicine, PA, USA; Department of Critical Care Medicine, University of Pittsburgh School of Medicine, PA, USA
| | - Robert H Garman
- Department of Pathology, University of Pittsburgh, Pittsburgh, PA, USA
| | - Francis Kim
- Department of Medicine, Harborview Medical Center, University of Washington, Seattle, WA, USA
| | - Patrick M Kochanek
- Safar Center for Resuscitation Research, University of Pittsburgh School of Medicine, PA, USA; Department of Critical Care Medicine, University of Pittsburgh School of Medicine, PA, USA
| | - Cameron Dezfulian
- Safar Center for Resuscitation Research, University of Pittsburgh School of Medicine, PA, USA; Department of Critical Care Medicine, University of Pittsburgh School of Medicine, PA, USA; Vascular Medicine Institute, University of Pittsburgh, Pittsburgh, PA, USA.
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8
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Borgognone A, Shantsila E, Worrall SM, Prompunt E, Loka T, Loudon BL, Chimen M, Ed Rainger G, Lord JM, Turner A, Nightingale P, Feelisch M, Kirchhof P, Lip GYH, Watson SP, Frenneaux MP, Madhani M. Nitrite circumvents platelet resistance to nitric oxide in patients with heart failure preserved ejection fraction and chronic atrial fibrillation. Cardiovasc Res 2019; 114:1313-1323. [PMID: 29659727 PMCID: PMC6054254 DOI: 10.1093/cvr/cvy087] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/05/2016] [Accepted: 04/09/2018] [Indexed: 12/18/2022] Open
Abstract
Aims Heart failure (HF) is a pro-thrombotic state. Both platelet and vascular responses to nitric oxide (NO) donors are impaired in HF patients with reduced ejection fraction (HFrEF) compared with healthy volunteers (HVs) due to scavenging of NO, and possibly also reduced activity of the principal NO sensor, soluble guanylate cyclase (sGC), limiting the therapeutic potential of NO donors as anti-aggregatory agents. Previous studies have shown that nitrite inhibits platelet activation presumptively after its reduction to NO, but the mechanism(s) involved remain poorly characterized. Our aim was to compare the effects of nitrite on platelet function in HV vs. HF patients with preserved ejection fraction (HFpEF) and chronic atrial fibrillation (HFpEF–AF), vs. patients with chronic AF without HF, and to assess whether these effects occur independent of the interaction with other formed elements of blood. Methods and results Platelet responses to nitrite and the NO donor sodium nitroprusside (SNP) were compared in age-matched HV controls (n = 12), HFpEF–AF patients (n = 29), and chronic AF patients (n = 8). Anti-aggregatory effects of nitrite in the presence of NO scavengers/sGC inhibitor were determined and vasodilator-stimulated phosphoprotein (VASP) phosphorylation was assessed using western blotting. In HV and chronic AF, both nitrite and SNP inhibited platelet aggregation in a concentration-dependent manner. Inhibition of platelet aggregation by the NO donor SNP was impaired in HFpEF-AF patients compared with healthy and chronic AF individuals, but there was no impairment of the anti-aggregatory effects of nitrite. Nitrite circumvented platelet NO resistance independently of other blood cells by directly activating sGC and phosphorylating VASP. Conclusion We here show for the first time that HFpEF-AF (but not chronic AF without HF) is associated with marked impairment of platelet NO responses due to sGC dysfunction and nitrite circumvents the ‘platelet NO resistance’ phenomenon in human HFpEF, at least partly, by acting as a direct sGC activator independent of NO.
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Affiliation(s)
- Alessandra Borgognone
- Institute of Cardiovascular Sciences, University of Birmingham, Edgbaston, Birmingham B15 2TT, UK
| | - Eduard Shantsila
- Institute of Cardiovascular Sciences, University of Birmingham, Edgbaston, Birmingham B15 2TT, UK.,Sandwell and West Birmingham NHS Trust, City Hospital, Birmingham B18 7QH, UK
| | - Sophie M Worrall
- Institute of Cardiovascular Sciences, University of Birmingham, Edgbaston, Birmingham B15 2TT, UK
| | - Eakkapote Prompunt
- Institute of Cardiovascular Sciences, University of Birmingham, Edgbaston, Birmingham B15 2TT, UK
| | - Thomas Loka
- Institute of Cardiovascular Sciences, University of Birmingham, Edgbaston, Birmingham B15 2TT, UK
| | - Brodie L Loudon
- Norwich Medical School, University of East Anglia, Norwich NR4 7UQ, UK
| | - Myriam Chimen
- Institute of Cardiovascular Sciences, University of Birmingham, Edgbaston, Birmingham B15 2TT, UK
| | - G Ed Rainger
- Institute of Cardiovascular Sciences, University of Birmingham, Edgbaston, Birmingham B15 2TT, UK
| | - Janet M Lord
- Institute of Inflammation and Ageing, University of Birmingham, Edgbaston, Birmingham B15 2TT, UK
| | - Ashley Turner
- Sandwell and West Birmingham NHS Trust, City Hospital, Birmingham B18 7QH, UK
| | - Peter Nightingale
- Wellcome Trust Clinical Research Facility, Queen Elizabeth Hospital, Edgbaston, Birmingham B15 2TT, UK
| | - Martin Feelisch
- Clinical and Experimental Sciences, Faculty of Medicine, University of Southampton, Southampton SO16 6YD, UK
| | - Paulus Kirchhof
- Institute of Cardiovascular Sciences, University of Birmingham, Edgbaston, Birmingham B15 2TT, UK.,Sandwell and West Birmingham NHS Trust, City Hospital, Birmingham B18 7QH, UK
| | - Gregory Y H Lip
- Institute of Cardiovascular Sciences, University of Birmingham, Edgbaston, Birmingham B15 2TT, UK.,Sandwell and West Birmingham NHS Trust, City Hospital, Birmingham B18 7QH, UK
| | - Steve P Watson
- Institute of Cardiovascular Sciences, University of Birmingham, Edgbaston, Birmingham B15 2TT, UK
| | | | - Melanie Madhani
- Institute of Cardiovascular Sciences, University of Birmingham, Edgbaston, Birmingham B15 2TT, UK
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9
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Tamargo J, Caballero R, Delpón E. New drugs in preclinical and early stage clinical development in the treatment of heart failure. Expert Opin Investig Drugs 2018; 28:51-71. [DOI: 10.1080/13543784.2019.1551357] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Affiliation(s)
- Juan Tamargo
- Department of Pharmacology and Toxicology, School of Medicine, Universidad Complutense, CIBERCV, Madrid,
Spain
| | - Ricardo Caballero
- Department of Pharmacology and Toxicology, School of Medicine, Universidad Complutense, CIBERCV, Madrid,
Spain
| | - Eva Delpón
- Department of Pharmacology and Toxicology, School of Medicine, Universidad Complutense, CIBERCV, Madrid,
Spain
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10
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Zhang T, Pan D, Su M, Fu LM, Miao CY, Yan QY, Wang J, Yang LG, Wang SK, Sun GJ. Determination of dietary nitrite in patients with esophageal pre-cancerous lesion and normal people: a duplicate diet study. Food Addit Contam Part A Chem Anal Control Expo Risk Assess 2018; 35:2298-2308. [DOI: 10.1080/19440049.2018.1546906] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Affiliation(s)
- Ting Zhang
- Key Laboratory of Environmental Medicine and Engineering of Ministry of Education, and Department of Nutrition and Food Hygiene, School of Public Health, Southeast University, Nanjing, P.R. China
| | - Da Pan
- Key Laboratory of Environmental Medicine and Engineering of Ministry of Education, and Department of Nutrition and Food Hygiene, School of Public Health, Southeast University, Nanjing, P.R. China
| | - Ming Su
- Chronic Noncommunicable Disease Prevention Department, Huai’an District Center for Disease Control and Prevention, Huai’an, P.R. China
| | - Ling-Meng Fu
- Key Laboratory of Environmental Medicine and Engineering of Ministry of Education, and Department of Nutrition and Food Hygiene, School of Public Health, Southeast University, Nanjing, P.R. China
| | - Cai-Yun Miao
- Chronic Noncommunicable Disease Prevention Department, Huai’an District Center for Disease Control and Prevention, Huai’an, P.R. China
| | - Qing-Yang Yan
- Chronic Noncommunicable Disease Prevention Department, Huai’an District Center for Disease Control and Prevention, Huai’an, P.R. China
| | - Jing Wang
- Key Laboratory of Environmental Medicine and Engineering of Ministry of Education, and Department of Nutrition and Food Hygiene, School of Public Health, Southeast University, Nanjing, P.R. China
| | - Li-Gang Yang
- Key Laboratory of Environmental Medicine and Engineering of Ministry of Education, and Department of Nutrition and Food Hygiene, School of Public Health, Southeast University, Nanjing, P.R. China
| | - Shao-Kang Wang
- Key Laboratory of Environmental Medicine and Engineering of Ministry of Education, and Department of Nutrition and Food Hygiene, School of Public Health, Southeast University, Nanjing, P.R. China
| | - Gui-Ju Sun
- Key Laboratory of Environmental Medicine and Engineering of Ministry of Education, and Department of Nutrition and Food Hygiene, School of Public Health, Southeast University, Nanjing, P.R. China
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11
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Kerley CP, James PE, McGowan A, Faul J, Cormican L. Dietary nitrate improved exercise capacity in COPD but not blood pressure or pulmonary function: a 2 week, double-blind randomised, placebo-controlled crossover trial. Int J Food Sci Nutr 2018; 70:222-231. [PMID: 30188220 DOI: 10.1080/09637486.2018.1492521] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
Dietary nitrate may improve exercise tolerance in some healthy and clinical populations. Existing data regarding dietary nitrate in COPD is inconsistent. We conducted a 14d double-blind, randomised, placebo-controlled, crossover trial of daily nitrate-rich beetroot juice (BRJ; 12.9 mmol) versus nitrate-depleted BRJ (PL; 0.5 mmol). At baseline and after each condition, we assessed functional capacity (incremental shuttle walk test; ISWT), ambulatory blood pressure, pulmonary function, quality of life as well as exhaled nitric oxide (eNO), and plasma nitrate/nitrite (NOx). Eight subjects with COPD completed the trial. BRJ supplementation was associated with significantly increased NOx (p < .05) and a 14.6% increase in ISWT distance (+56 m, p = .00004) as well as a trend towards increased eNO compared to PL. There was no other differences. Dietary nitrate appears to have ergogenic effect in subjects with mild-moderate COPD. This effect does not appear to be related to altering blood pressure or pulmonary function.
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Affiliation(s)
- Conor P Kerley
- a Respiratory and Sleep Diagnostics Department , Connolly Hospital , Dublin , Ireland.,b School of Biological Sciences , Dublin Institute of Technology , Dublin , Ireland
| | - Philip E James
- c School of Health Sciences , Cardiff Metropolitan University , Cardiff, UK
| | - Aisling McGowan
- a Respiratory and Sleep Diagnostics Department , Connolly Hospital , Dublin , Ireland
| | - John Faul
- a Respiratory and Sleep Diagnostics Department , Connolly Hospital , Dublin , Ireland
| | - Liam Cormican
- a Respiratory and Sleep Diagnostics Department , Connolly Hospital , Dublin , Ireland
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12
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Edwards TM, Hamlin HJ. Reproductive endocrinology of environmental nitrate. Gen Comp Endocrinol 2018; 265:31-40. [PMID: 29577898 DOI: 10.1016/j.ygcen.2018.03.021] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/02/2017] [Revised: 03/19/2018] [Accepted: 03/20/2018] [Indexed: 12/19/2022]
Abstract
Nitrate is a widespread contaminant of aquatic ecosystems and drinking water. It is also broadly active in organismal physiology, and as such, has the potential to both enhance and disrupt normal physiological function. In animals, nitrate is a proposed endocrine disrupter that is converted in vivo to nitrite and nitric oxide. Nitric oxide, in particular, is a potent cell signaling molecule that participates in diverse biological pathways and events. Here, we review in vivo nitrate cycling and downstream mechanistic physiology, with an emphasis on reproductive outcomes. However, in many cases, the research produces contradictory results, in part because there is good evidence that nitrate follows a non-monotonic dose-response curve. This conundrum highlights an array of opportunities for scientists from different fields to collaborate for a full understanding of nitrate physiology. Opposing conclusions are especially likely when in vivo/in vitro, long term/short term, high dose/low dose, or hypoxia/normoxia studies are compared. We conclude that in vivo studies are most appropriate for testing an organism's integrated endocrine response to nitrate. Based on the limited available studies, there is a generalized trend that shorter term studies (less than 1 month) or studies involving low doses (≤5 mg/L NO3-N) cause steroid hormone levels to decline. Studies that last more than a month and/or involve higher, but still environmentally relevant, exposures (>50-100 mg/L NO3-N) cause steroid hormone levels to increase. Very high nitrate doses (>500 mg/L NO3-N) are cytotoxic in many species. Hypoxia and acidity are likely to intensify the effects of nitrate. For study design, degree of study animal reproductive maturity or activity is important, with immature/reproductively quiescent animals responding to nitrate differently, compared with reproductively active animals. A detailed table of studies is presented.
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Affiliation(s)
- Thea M Edwards
- Department of Biology, University of the South, Sewanee, TN, USA.
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13
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Kim F, Dezfulian C, Empey PE, Morrell M, Olsufka M, Scruggs S, Kudenchuk P, May S, Maynard C, Sayre MR, Nichol G. Usefulness of Intravenous Sodium Nitrite During Resuscitation for the Treatment of Out-of-Hospital Cardiac Arrest. Am J Cardiol 2018; 122:554-559. [PMID: 30205886 DOI: 10.1016/j.amjcard.2018.04.060] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/03/2018] [Revised: 04/24/2018] [Accepted: 04/30/2018] [Indexed: 01/02/2023]
Abstract
It is hypothesized that intravenous (IV) sodium nitrite given during resuscitation of out-of-hospital cardiac arrest (OHCA) will improve survival. We performed a phase 1 open-label study of IV sodium nitrite given during resuscitation of 120 patents with OHCA from ventricular fibrillation or nonventricular fibrillation initial rhythms by Seattle Fire Department paramedics. A total of 59 patients received 25 mg (low) and 61 patients received 60 mg (high) of sodium nitrite during resuscitation from OHCA. Treatment effects were compared between high- and low-dose nitrite groups, and all patients in a concurrent local Emergency Medical Services registry of OHCA. Whole blood nitrite levels were measured in 97 patients. The rate of return of spontaneous circulation (48% vs 49%), rearrest in the field (15% vs 25%), use of norepinephrine (12% vs 12%), first systolic blood pressure (124 ± 32 vs 125 ± 38 mm Hg), survival to discharge (23.7% vs 16.4%), and neurologically favorable survival (18.6% vs 11.5%) were not significantly different in the low and high nitrite groups. There were no significant differences in these outcomes among patients who received IV nitrite compared with concurrent registry controls. We estimate that 60 mg achieves whole blood nitrite levels of 22 to 38 μM 10 minutes after administration, whereas 25 mg achieves a level of 9 to 16 μM 10 minutes after delivery. In conclusion, administration of IV nitrite is feasible and appears to be safe in patients with OHCA, permitting subsequent evaluation of the effectiveness of IV nitrite for the treatment of OHCA.
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Affiliation(s)
- Francis Kim
- Department of Medicine, Harborview Medical Center, University of Washington, Seattle, Washington.
| | - Cameron Dezfulian
- Department of Critical Care Medicine, Safar Center for Resuscitation Research and Vascular Medicine Institute, University of Pittsburgh, Pittsburgh, Pennsylvania
| | - Philip E Empey
- Department of Pharmacy and Therapeutics, Center for Clinical Pharmaceutical Sciences, School of Pharmacy, University of Pittsburgh, Pittsburgh, Pennsylvania
| | - Matthew Morrell
- Division of Pulmonary, Allergy, and Critical Care Medicine, Department of Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania
| | - Michele Olsufka
- Department of Medicine, Harborview Medical Center, University of Washington, Seattle, Washington
| | - Sue Scruggs
- Department of Medicine, Harborview Medical Center, University of Washington, Seattle, Washington
| | - Peter Kudenchuk
- Department of Medicine, Harborview Medical Center, University of Washington, Seattle, Washington
| | - Susanne May
- Department of Biostatistics, University of Washington, Seattle, Washington
| | - Charles Maynard
- Department of Health Services, University of Washington, Seattle, Washington
| | - Michael R Sayre
- Department of Emergency Medicine, Harborview Medical Center, University of Washington, Seattle, Washington
| | - Graham Nichol
- Department of Medicine, Harborview Medical Center, University of Washington, Seattle, Washington; Department of Emergency Medicine, Harborview Medical Center, University of Washington, Seattle, Washington
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14
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Yingchoncharoen T, Rakyhao T, Chuncharunee S, Sritara P, Pienvichit P, Paiboonsukwong K, Sathavorasmith P, Sirirat K, Sriwantana T, Srihirun S, Sibmooh N. Inhaled nebulized sodium nitrite decreases pulmonary artery pressure in β-thalassemia patients with pulmonary hypertension. Nitric Oxide 2018; 76:174-178. [DOI: 10.1016/j.niox.2017.09.010] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2017] [Revised: 09/23/2017] [Accepted: 09/26/2017] [Indexed: 01/19/2023]
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15
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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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16
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Dezfulian C, Olsufka M, Fly D, Scruggs S, Do R, Maynard C, Nichol G, Kim F. Hemodynamic effects of IV sodium nitrite in hospitalized comatose survivors of out of hospital cardiac arrest. Resuscitation 2017; 122:106-112. [PMID: 29175357 DOI: 10.1016/j.resuscitation.2017.11.055] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2017] [Revised: 11/08/2017] [Accepted: 11/22/2017] [Indexed: 12/24/2022]
Abstract
BACKGROUND Patients resuscitated from cardiac arrest have brain and cardiac injury. Recent animal studies suggest that the administration of sodium nitrite after resuscitation from 12min of asystole limits acute cardiac dysfunction and improves survival and neurologic outcomes. It has been hypothesized that low doses of IV sodium nitrite given during resuscitation of out of hospital cardiac arrest (OHCA) will improve survival. Low doses of sodium nitrite (e.g., 9.6mg of sodium nitrite) are safe in healthy individuals, however the effect of nitrite on blood pressure in resuscitated cardiac arrest patients is unknown. METHODS We performed a single-center, pilot trial of low dose sodium nitrite (1 or 9.6mg dose) vs. placebo in hospitalized out-of-hospital cardiac arrest patient to determine whether nitrite administration reduced blood pressure and whether whole blood nitrite levels increased in response to nitrite administration. RESULTS This is the first reported study of sodium nitrite in cardiac arrest patients. Infusion of low doses of sodium nitrite in comatose survivors of OHCA (n=7) compared to placebo (n=4) had no significant effects on heart rate within 30min after infusion (70±20 vs. 78±3 beats per minute, p=0.18), systolic blood pressure (103±20 vs 108±15mmHg, p=0.3), or methemoglobin levels (0.92±0.33 vs. 0.70±0.26, p=0.45). Serum nitrite levels of 2-4μM were achieved within 15min of a 9.6mg nitrite infusion. CONCLUSIONS Low dose sodium nitrite does not cause significant hemodynamic effect in patients with OHCA, which suggests that nitrite can be delivered safely in this critically ill patient population. Higher doses of sodium nitrite are necessary in order to achieve target serum level of 10μM.
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Affiliation(s)
- Cameron Dezfulian
- Department of Adult and Pediatric Critical Care Medicine, Safar Center for Resuscitation Research and Vascular Medicine Institute, University of Pittsburgh, United States
| | - Michele Olsufka
- Department of Medicine, Harborview Medical Center, University of Washington, United States
| | - Deborah Fly
- Department of Medicine, Harborview Medical Center, University of Washington, United States
| | - Sue Scruggs
- Department of Medicine, Harborview Medical Center, University of Washington, United States
| | - Rose Do
- Department of Medicine, Harborview Medical Center, University of Washington, United States
| | - Charles Maynard
- Department of Health Services, University of Washington, United States
| | - Graham Nichol
- Department of Medicine, Harborview Medical Center, University of Washington, United States
| | - Francis Kim
- Department of Medicine, Harborview Medical Center, University of Washington, United States.
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17
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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: 65] [Impact Index Per Article: 9.3] [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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18
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Reddy YNV, Lewis GD, Shah SJ, LeWinter M, Semigran M, Davila-Roman VG, Anstrom K, Hernandez A, Braunwald E, Redfield MM, Borlaug BA. INDIE-HFpEF (Inorganic Nitrite Delivery to Improve Exercise Capacity in Heart Failure With Preserved Ejection Fraction): Rationale and Design. Circ Heart Fail 2017; 10:CIRCHEARTFAILURE.117.003862. [PMID: 28476756 DOI: 10.1161/circheartfailure.117.003862] [Citation(s) in RCA: 43] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/21/2017] [Accepted: 03/29/2017] [Indexed: 02/06/2023]
Abstract
Approximately half of patients with heart failure have preserved ejection fraction. There is no proven treatment that improves outcome. The pathophysiology of heart failure with preserved ejection fraction is complex and includes left ventricular systolic and diastolic dysfunction, pulmonary vascular disease, endothelial dysfunction, and peripheral abnormalities. Multiple lines of evidence point to impaired nitric oxide (NO)-cGMP bioavailability as playing a central role in each of these abnormalities. In contrast to traditional organic nitrate therapies, an alternative strategy to restore NO-cGMP signaling is via inorganic nitrite. Inorganic nitrite, previously considered to be an inert byproduct of NO metabolism, functions as an important in vivo reservoir for NO generation, particularly under hypoxic and acidosis conditions. As such, inorganic nitrite becomes most active at times of greater need for NO signaling, as during exercise when left ventricular filling pressures and pulmonary artery pressures increase. Herein, we present the rationale and design for the INDIE-HFpEF trial (Inorganic Nitrite Delivery to Improve Exercise Capacity in Heart Failure with Preserved Ejection Fraction), which is a multicenter, randomized, double-blind, placebo-controlled cross-over study assessing the effect of inhaled inorganic nitrite on peak exercise capacity, conducted in the National Heart, Lung, and Blood Institute-sponsored Heart Failure Clinical Research Network. CLINICAL TRIAL REGISTRATION URL: http://www.clinicaltrials.gov. Unique identifier: NCT02742129.
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Affiliation(s)
- Yogesh N V Reddy
- From the Department of Cardiovascular Medicine, Mayo Clinic, Rochester, MN (Y.N.V.R., M.M.R., B.A.B.); Division of Cardiovascular Medicine, Department of Medicine, Massachusetts General Hospital, Boston (G.D.L., M.S.); Division of Cardiology, Department of Medicine, Northwestern University Feinberg School of Medicine, Chicago, IL (S.J.S.); Cardiology Unit, University of Vermont College of Medicine, Burlington (M.L.W.); Cardiovascular Division, Washington University School of Medicine, St. Louis, MO (V.G.D.-R.); Department of Medicine, Duke Clinical Research Institute, Duke University School of Medicine, Durham, NC (K.A., A.H.); and Cardiovascular Division, Department of Medicine, Brigham and Women's Hospital, Boston, MA (E.B.)
| | - Gregory D Lewis
- From the Department of Cardiovascular Medicine, Mayo Clinic, Rochester, MN (Y.N.V.R., M.M.R., B.A.B.); Division of Cardiovascular Medicine, Department of Medicine, Massachusetts General Hospital, Boston (G.D.L., M.S.); Division of Cardiology, Department of Medicine, Northwestern University Feinberg School of Medicine, Chicago, IL (S.J.S.); Cardiology Unit, University of Vermont College of Medicine, Burlington (M.L.W.); Cardiovascular Division, Washington University School of Medicine, St. Louis, MO (V.G.D.-R.); Department of Medicine, Duke Clinical Research Institute, Duke University School of Medicine, Durham, NC (K.A., A.H.); and Cardiovascular Division, Department of Medicine, Brigham and Women's Hospital, Boston, MA (E.B.)
| | - Sanjiv J Shah
- From the Department of Cardiovascular Medicine, Mayo Clinic, Rochester, MN (Y.N.V.R., M.M.R., B.A.B.); Division of Cardiovascular Medicine, Department of Medicine, Massachusetts General Hospital, Boston (G.D.L., M.S.); Division of Cardiology, Department of Medicine, Northwestern University Feinberg School of Medicine, Chicago, IL (S.J.S.); Cardiology Unit, University of Vermont College of Medicine, Burlington (M.L.W.); Cardiovascular Division, Washington University School of Medicine, St. Louis, MO (V.G.D.-R.); Department of Medicine, Duke Clinical Research Institute, Duke University School of Medicine, Durham, NC (K.A., A.H.); and Cardiovascular Division, Department of Medicine, Brigham and Women's Hospital, Boston, MA (E.B.)
| | - Martin LeWinter
- From the Department of Cardiovascular Medicine, Mayo Clinic, Rochester, MN (Y.N.V.R., M.M.R., B.A.B.); Division of Cardiovascular Medicine, Department of Medicine, Massachusetts General Hospital, Boston (G.D.L., M.S.); Division of Cardiology, Department of Medicine, Northwestern University Feinberg School of Medicine, Chicago, IL (S.J.S.); Cardiology Unit, University of Vermont College of Medicine, Burlington (M.L.W.); Cardiovascular Division, Washington University School of Medicine, St. Louis, MO (V.G.D.-R.); Department of Medicine, Duke Clinical Research Institute, Duke University School of Medicine, Durham, NC (K.A., A.H.); and Cardiovascular Division, Department of Medicine, Brigham and Women's Hospital, Boston, MA (E.B.)
| | - Marc Semigran
- From the Department of Cardiovascular Medicine, Mayo Clinic, Rochester, MN (Y.N.V.R., M.M.R., B.A.B.); Division of Cardiovascular Medicine, Department of Medicine, Massachusetts General Hospital, Boston (G.D.L., M.S.); Division of Cardiology, Department of Medicine, Northwestern University Feinberg School of Medicine, Chicago, IL (S.J.S.); Cardiology Unit, University of Vermont College of Medicine, Burlington (M.L.W.); Cardiovascular Division, Washington University School of Medicine, St. Louis, MO (V.G.D.-R.); Department of Medicine, Duke Clinical Research Institute, Duke University School of Medicine, Durham, NC (K.A., A.H.); and Cardiovascular Division, Department of Medicine, Brigham and Women's Hospital, Boston, MA (E.B.)
| | - Victor G Davila-Roman
- From the Department of Cardiovascular Medicine, Mayo Clinic, Rochester, MN (Y.N.V.R., M.M.R., B.A.B.); Division of Cardiovascular Medicine, Department of Medicine, Massachusetts General Hospital, Boston (G.D.L., M.S.); Division of Cardiology, Department of Medicine, Northwestern University Feinberg School of Medicine, Chicago, IL (S.J.S.); Cardiology Unit, University of Vermont College of Medicine, Burlington (M.L.W.); Cardiovascular Division, Washington University School of Medicine, St. Louis, MO (V.G.D.-R.); Department of Medicine, Duke Clinical Research Institute, Duke University School of Medicine, Durham, NC (K.A., A.H.); and Cardiovascular Division, Department of Medicine, Brigham and Women's Hospital, Boston, MA (E.B.)
| | - Kevin Anstrom
- From the Department of Cardiovascular Medicine, Mayo Clinic, Rochester, MN (Y.N.V.R., M.M.R., B.A.B.); Division of Cardiovascular Medicine, Department of Medicine, Massachusetts General Hospital, Boston (G.D.L., M.S.); Division of Cardiology, Department of Medicine, Northwestern University Feinberg School of Medicine, Chicago, IL (S.J.S.); Cardiology Unit, University of Vermont College of Medicine, Burlington (M.L.W.); Cardiovascular Division, Washington University School of Medicine, St. Louis, MO (V.G.D.-R.); Department of Medicine, Duke Clinical Research Institute, Duke University School of Medicine, Durham, NC (K.A., A.H.); and Cardiovascular Division, Department of Medicine, Brigham and Women's Hospital, Boston, MA (E.B.)
| | - Adrian Hernandez
- From the Department of Cardiovascular Medicine, Mayo Clinic, Rochester, MN (Y.N.V.R., M.M.R., B.A.B.); Division of Cardiovascular Medicine, Department of Medicine, Massachusetts General Hospital, Boston (G.D.L., M.S.); Division of Cardiology, Department of Medicine, Northwestern University Feinberg School of Medicine, Chicago, IL (S.J.S.); Cardiology Unit, University of Vermont College of Medicine, Burlington (M.L.W.); Cardiovascular Division, Washington University School of Medicine, St. Louis, MO (V.G.D.-R.); Department of Medicine, Duke Clinical Research Institute, Duke University School of Medicine, Durham, NC (K.A., A.H.); and Cardiovascular Division, Department of Medicine, Brigham and Women's Hospital, Boston, MA (E.B.)
| | - Eugene Braunwald
- From the Department of Cardiovascular Medicine, Mayo Clinic, Rochester, MN (Y.N.V.R., M.M.R., B.A.B.); Division of Cardiovascular Medicine, Department of Medicine, Massachusetts General Hospital, Boston (G.D.L., M.S.); Division of Cardiology, Department of Medicine, Northwestern University Feinberg School of Medicine, Chicago, IL (S.J.S.); Cardiology Unit, University of Vermont College of Medicine, Burlington (M.L.W.); Cardiovascular Division, Washington University School of Medicine, St. Louis, MO (V.G.D.-R.); Department of Medicine, Duke Clinical Research Institute, Duke University School of Medicine, Durham, NC (K.A., A.H.); and Cardiovascular Division, Department of Medicine, Brigham and Women's Hospital, Boston, MA (E.B.)
| | - Margaret M Redfield
- From the Department of Cardiovascular Medicine, Mayo Clinic, Rochester, MN (Y.N.V.R., M.M.R., B.A.B.); Division of Cardiovascular Medicine, Department of Medicine, Massachusetts General Hospital, Boston (G.D.L., M.S.); Division of Cardiology, Department of Medicine, Northwestern University Feinberg School of Medicine, Chicago, IL (S.J.S.); Cardiology Unit, University of Vermont College of Medicine, Burlington (M.L.W.); Cardiovascular Division, Washington University School of Medicine, St. Louis, MO (V.G.D.-R.); Department of Medicine, Duke Clinical Research Institute, Duke University School of Medicine, Durham, NC (K.A., A.H.); and Cardiovascular Division, Department of Medicine, Brigham and Women's Hospital, Boston, MA (E.B.)
| | - Barry A Borlaug
- From the Department of Cardiovascular Medicine, Mayo Clinic, Rochester, MN (Y.N.V.R., M.M.R., B.A.B.); Division of Cardiovascular Medicine, Department of Medicine, Massachusetts General Hospital, Boston (G.D.L., M.S.); Division of Cardiology, Department of Medicine, Northwestern University Feinberg School of Medicine, Chicago, IL (S.J.S.); Cardiology Unit, University of Vermont College of Medicine, Burlington (M.L.W.); Cardiovascular Division, Washington University School of Medicine, St. Louis, MO (V.G.D.-R.); Department of Medicine, Duke Clinical Research Institute, Duke University School of Medicine, Durham, NC (K.A., A.H.); and Cardiovascular Division, Department of Medicine, Brigham and Women's Hospital, Boston, MA (E.B.).
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19
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Falls R, Seman M, Braat S, Sortino J, Allen JD, Neil CJ. Inorganic nitrate as a treatment for acute heart failure: a protocol for a single center, randomized, double-blind, placebo-controlled pilot and feasibility study. J Transl Med 2017; 15:172. [PMID: 28789663 PMCID: PMC5549289 DOI: 10.1186/s12967-017-1271-z] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2016] [Accepted: 07/24/2017] [Indexed: 01/07/2023] Open
Abstract
Background Acute heart failure (AHF) is a frequent reason for hospitalization worldwide and effective treatment options are limited. It is known that AHF is a condition characterized by impaired vasorelaxation, together with reduced nitric oxide (NO) bioavailability, an endogenous vasodilatory compound. Supplementation of inorganic sodium nitrate (NaNO3) is an indirect dietary source of NO, through bioconversion. It is proposed that oral sodium nitrate will favorably affect levels of circulating NO precursors (nitrate and nitrite) in AHF patients, resulting in reduced systemic vascular resistance, without significant hypotension. Methods and outcomes We propose a single center, randomized, double-blind, placebo-controlled pilot trial, evaluating the feasibility of sodium nitrate as a treatment for AHF. The primary hypothesis that sodium nitrate treatment will result in increased systemic levels of nitric oxide pre-cursors (nitrate and nitrite) in plasma, in parallel with improved vasorelaxation, as assessed by non-invasively derived systemic vascular resistance index. Additional surrogate measures relevant to the known pathophysiology of AHF will be obtained in order to assess clinical effect on dyspnea and renal function. Discussion The results of this study will provide evidence of the feasibility of this novel approach and will be of interest to the heart failure community. This trial may inform a larger study.
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Affiliation(s)
- Roman Falls
- Western Centre for Health Research and Education, Western Health, Melbourne, Australia.,Department of Medicine-Western Health, Melbourne Medical School, The University of Melbourne, Melbourne, Australia
| | - Michael Seman
- Western Centre for Health Research and Education, Western Health, Melbourne, Australia.,Department of Medicine-Western Health, Melbourne Medical School, The University of Melbourne, Melbourne, Australia
| | - Sabine Braat
- Department of Medicine-Western Health, Melbourne Medical School, The University of Melbourne, Melbourne, Australia.,Melbourne School of Population and Global Health and Melbourne Clinical and Translational Sciences Platform (MCATS), Parkville, Australia
| | - Joshua Sortino
- Western Centre for Health Research and Education, Western Health, Melbourne, Australia
| | - Jason D Allen
- Western Centre for Health Research and Education, Western Health, Melbourne, Australia.,Clinical Exercise Science Research Program, Institute of Sport Exercise and Active Living (ISEAL), Melbourne, Australia
| | - Christopher J Neil
- Western Centre for Health Research and Education, Western Health, Melbourne, Australia. .,Department of Medicine-Western Health, Melbourne Medical School, The University of Melbourne, Melbourne, Australia. .,Clinical Exercise Science Research Program, Institute of Sport Exercise and Active Living (ISEAL), Melbourne, Australia. .,Western Health Cardiology, Footscray Hospital, Gordon St, Locked Bag 2, Footscray, VIC, 3011, Australia.
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20
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The Use of Nitrates in the Management of Acute Heart Failure in the Emergency Department: a Review. CURRENT EMERGENCY AND HOSPITAL MEDICINE REPORTS 2017. [DOI: 10.1007/s40138-017-0132-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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21
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Dulce RA, Kulandavelu S, Schulman IH, Fritsch J, Hare JM. Nitric Oxide Regulation of Cardiovascular Physiology and Pathophysiology. Nitric Oxide 2017. [DOI: 10.1016/b978-0-12-804273-1.00024-7] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/03/2022]
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22
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Iwasaku T, Ando T, Eguchi A, Okuhara Y, Naito Y, Mano T, Masuyama T, Hirotani S. Adaptive Servo-Ventilation Treatment Increases Stroke Volume in Stable Systolic Heart Failure Patients With Low Tricuspid Annular Plane Systolic Excursion. Int Heart J 2017; 58:393-399. [DOI: 10.1536/ihj.16-327] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Affiliation(s)
- Toshihiro Iwasaku
- Division of Cardiovascular Medicine, Department of Internal Medicine, Hyogo College of Medicine
| | - Tomotaka Ando
- Division of Cardiovascular Medicine, Department of Internal Medicine, Hyogo College of Medicine
| | - Akiyo Eguchi
- Division of Cardiovascular Medicine, Department of Internal Medicine, Hyogo College of Medicine
| | - Yoshitaka Okuhara
- Division of Cardiovascular Medicine, Department of Internal Medicine, Hyogo College of Medicine
| | - Yoshiro Naito
- Division of Cardiovascular Medicine, Department of Internal Medicine, Hyogo College of Medicine
| | - Toshiaki Mano
- Division of Cardiovascular Medicine, Department of Internal Medicine, Hyogo College of Medicine
| | - Tohru Masuyama
- Division of Cardiovascular Medicine, Department of Internal Medicine, Hyogo College of Medicine
| | - Shinichi Hirotani
- Division of Cardiovascular Medicine, Department of Internal Medicine, Hyogo College of Medicine
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23
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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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24
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Simon MA, Vanderpool RR, Nouraie M, Bachman TN, White PM, Sugahara M, Gorcsan J, Parsley EL, Gladwin MT. Acute hemodynamic effects of inhaled sodium nitrite in pulmonary hypertension associated with heart failure with preserved ejection fraction. JCI Insight 2016; 1:e89620. [PMID: 27812547 PMCID: PMC5085611 DOI: 10.1172/jci.insight.89620] [Citation(s) in RCA: 67] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2016] [Accepted: 09/29/2016] [Indexed: 01/08/2023] Open
Abstract
BACKGROUND Pulmonary hypertension (PH) is associated with poor outcomes, yet specific treatments only exist for a small subset of patients. The most common form of PH is that associated with left heart disease (Group 2), for which there is no approved therapy. Nitrite has shown efficacy in preclinical animal models of Group 1 and 2 PH, as well as in patients with left heart failure with preserved ejection fraction (HFpEF). We evaluated the safety and efficacy of a potentially novel inhaled formulation of nitrite in PH-HFpEF patients as compared with Group 1 and 3 PH. METHODS Cardiopulmonary hemodynamics were recorded after acute administration of inhaled nitrite at 2 doses, 45 and 90 mg. Safety endpoints included change in systemic blood pressure and methemoglobin levels. Responses were also compared with those administered inhaled nitric oxide. RESULTS Thirty-six patients were enrolled (10 PH-HFpEF, 20 Group 1 pulmonary arterial hypertension patients on background PH-specific therapy, and 6 Group 3 PH). Drug administration was well tolerated. Nitrite inhalation significantly lowered pulmonary, right atrial, and pulmonary capillary wedge pressures, most pronounced in patients with PH-HFpEF. There was a modest decrease in cardiac output and systemic blood pressure. Pulmonary vascular resistance decreased only in Group 3 PH patients. There was substantial increase in pulmonary artery compliance, most pronounced in patients with PH-HFpEF. CONCLUSIONS Inhaled nitrite is safe in PH patients and may be efficacious in PH-HFpEF and Group 3 PH primarily via improvements in left and right ventricular filling pressures and pulmonary artery compliance. The lack of change in pulmonary vascular resistance likely may limit efficacy for Group 1 patients. TRIAL REGISTRATION ClinicalTrials.gov NCT01431313 FUNDING. This work was supported in part by the NIH grants P01HL103455 (to MAS and MTG), R01HL098032 (to MTG), and R01HL096973 (to MTG), and Mast Therapeutics, Inc.
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Affiliation(s)
- Marc A. Simon
- Heart and Vascular Institute
- Pittsburgh Heart, Lung, Blood and Vascular Medicine Institute
- Department of Bioengineering, and
- Division of Pulmonary, Allergy and Critical Care Medicine, Department of Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania, USA
| | - Rebecca R. Vanderpool
- Pittsburgh Heart, Lung, Blood and Vascular Medicine Institute
- Department of Bioengineering, and
| | - Mehdi Nouraie
- Pittsburgh Heart, Lung, Blood and Vascular Medicine Institute
- Division of Pulmonary, Allergy and Critical Care Medicine, Department of Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania, USA
| | - Timothy N. Bachman
- Pittsburgh Heart, Lung, Blood and Vascular Medicine Institute
- Department of Bioengineering, and
| | - Pamela M. White
- Division of Pulmonary, Allergy and Critical Care Medicine, Department of Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania, USA
| | | | | | | | - Mark T. Gladwin
- Pittsburgh Heart, Lung, Blood and Vascular Medicine Institute
- Division of Pulmonary, Allergy and Critical Care Medicine, Department of Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania, USA
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25
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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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26
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Dezfulian C, Kenny E, Lamade A, Misse A, Krehel N, St Croix C, Kelley EE, Jackson TC, Uray T, Rackley J, Kochanek PM, Clark RSB, Bayir H. Mechanistic characterization of nitrite-mediated neuroprotection after experimental cardiac arrest. J Neurochem 2016; 139:419-431. [PMID: 27507435 DOI: 10.1111/jnc.13764] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2016] [Revised: 08/04/2016] [Accepted: 08/05/2016] [Indexed: 12/27/2022]
Abstract
Nitrite acts as an ischemic reservoir of nitric oxide (NO) and a potent S-nitrosating agent which reduced histologic brain injury after rat asphyxial cardiac arrest (ACA). The mechanism(s) of nitrite-mediated neuroprotection remain to be defined. We hypothesized that nitrite-mediated brain mitochondrial S-nitrosation accounts for neuroprotection by reducing reperfusion reactive oxygen species (ROS) generation. Nitrite (4 μmol) or placebo was infused IV after normothermic (37°C) ACA in randomized, blinded fashion with evaluation of neurologic function, survival, brain mitochondrial function, and ROS. Blood and CSF nitrite were quantified using reductive chemiluminescence and S-nitrosation by biotin switch. Direct neuroprotection was verified in vitro after 1 and 4 h neuronal oxygen glucose deprivation measuring neuronal death with inhibition studies to examine mechanism. Mitochondrial ROS generation was quantified by live neuronal imaging using mitoSOX. Nitrite significantly reduced neurologic disability after ACA. ROS generation was reduced in brain mitochondria from nitrite- versus placebo-treated rats after ACA with congruent preservation of brain ascorbate and reduction of ROS in brain sections using immuno-spin trapping. ATP generation was maintained with nitrite up to 24 h after ACA. Nitrite rapidly entered CSF and increased brain mitochondrial S-nitrosation. Nitrite reduced in vitro mitochondrial superoxide generation and improved survival of neurons after oxygen glucose deprivation. Protection was maintained with inhibition of soluble guanylate cyclase but lost with NO scavenging and ultraviolet irradiation. Nitrite therapy results in direct neuroprotection from ACA mediated by reductions in brain mitochondrial ROS in association with protein S-nitrosation. Neuroprotection is dependent on NO and S-nitrosothiol generation, not soluble guanylate cyclase.
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Affiliation(s)
- Cameron Dezfulian
- Safar Center for Resuscitation Research, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA. .,Department of Critical Care Medicine, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA. .,Vascular Medicine Institute, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA.
| | - Elizabeth Kenny
- Safar Center for Resuscitation Research, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA
| | - Andrew Lamade
- Safar Center for Resuscitation Research, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA
| | - Amalea Misse
- Safar Center for Resuscitation Research, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA.,Department of Critical Care Medicine, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA
| | - Nicholas Krehel
- Safar Center for Resuscitation Research, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA
| | - Claudette St Croix
- Department of Cell Biology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA
| | - Eric E Kelley
- Department of Pharmacology and Chemical Biology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA
| | - Travis C Jackson
- Safar Center for Resuscitation Research, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA.,Department of Critical Care Medicine, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA
| | - Thomas Uray
- Safar Center for Resuscitation Research, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA
| | - Justin Rackley
- Safar Center for Resuscitation Research, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA
| | - Patrick M Kochanek
- Safar Center for Resuscitation Research, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA.,Department of Critical Care Medicine, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA
| | - Robert S B Clark
- Safar Center for Resuscitation Research, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA.,Department of Critical Care Medicine, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA
| | - Hulya Bayir
- Safar Center for Resuscitation Research, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA.,Department of Critical Care Medicine, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA.,Department of Environmental and Occupational Health, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA
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27
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Borlaug BA, Melenovsky V, Koepp KE. Inhaled Sodium Nitrite Improves Rest and Exercise Hemodynamics in Heart Failure With Preserved Ejection Fraction. Circ Res 2016; 119:880-6. [PMID: 27458234 DOI: 10.1161/circresaha.116.309184] [Citation(s) in RCA: 115] [Impact Index Per Article: 14.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/26/2016] [Accepted: 07/25/2016] [Indexed: 12/14/2022]
Abstract
RATIONALE Abnormalities in nitric oxide signaling play a pivotal role in heart failure with preserved ejection fraction (HFpEF). Intravenous sodium nitrite, which is converted to nitric oxide in vivo, improves hemodynamics in HFpEF, but its use is limited by the need for parenteral administration. Nitrite can also be administered using a novel, portable micronebulizer system suitable for chronic use. OBJECTIVE Determine whether inhaled nitrite improves hemodynamics in HFpEF. METHODS AND RESULTS In a double-blind, randomized, placebo-controlled, parallel-group trial, subjects with HFpEF (n=26) underwent cardiac catheterization with simultaneous expired gas analysis at rest and during exercise before and after treatment with inhaled sodium nitrite (90 mg) or placebo. The primary end point was the pulmonary capillary wedge pressure during exercise. Before study drug administration, HFpEF subjects displayed an increase in pulmonary capillary wedge pressure with exercise from 20±6 to 34±7 mm Hg (P<0.0001). After study drug administration, exercise pulmonary capillary wedge pressure was substantially improved by nitrite as compared with placebo (baseline-adjusted mean 25±5 versus 31±6 mm Hg; analysis of covariance P=0.022). Inhaled nitrite reduced resting pulmonary capillary wedge pressure (-4±3 versus -1±2 mm Hg; P=0.002), improved pulmonary artery compliance (+1.5±1.1 versus +0.6±0.9 mL/mm Hg), and decreased mean pulmonary artery pressures at rest (-7±4 versus -3±4 mm Hg; P=0.007) and with exercise (-10±6 versus -5±6 mm Hg; P=0.05). Nitrite reduced right atrial pressures, with no effect on cardiac output or stroke volume. CONCLUSIONS Acute administration of inhaled sodium nitrite reduces biventricular filling pressures and pulmonary artery pressures at rest and during exercise in HFpEF. Further study is warranted to evaluate chronic effects of inhaled nitrite in HFpEF. CLINICAL TRIAL REGISTRATION This single center randomized clinical trial is registered at clinicaltrials.gov (NCT02262078).
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Affiliation(s)
- Barry A Borlaug
- From the Division of Cardiovascular Diseases, Department of Medicine, Mayo Clinic Rochester, MN.
| | - Vojtech Melenovsky
- From the Division of Cardiovascular Diseases, Department of Medicine, Mayo Clinic Rochester, MN
| | - Katlyn E Koepp
- From the Division of Cardiovascular Diseases, Department of Medicine, Mayo Clinic Rochester, MN
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28
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Loudon BL, Noordali H, Gollop ND, Frenneaux MP, Madhani M. Present and future pharmacotherapeutic agents in heart failure: an evolving paradigm. Br J Pharmacol 2016; 173:1911-24. [PMID: 26993743 PMCID: PMC4882493 DOI: 10.1111/bph.13480] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2015] [Revised: 01/28/2016] [Accepted: 02/26/2016] [Indexed: 02/06/2023] Open
Abstract
Many conditions culminate in heart failure (HF), a multi‐organ systemic syndrome with an intrinsically poor prognosis. Pharmacotherapeutic agents that correct neurohormonal dysregulation and haemodynamic instability have occupied the forefront of developments within the treatment of HF in the past. Indeed, multiple trials aimed to validate these agents in the 1980s and early 1990s, resulting in a large and robust evidence‐base supporting their use clinically. An established treatment paradigm now exists for the treatment of HF with reduced ejection fraction (HFrEF), but there have been very few notable developments in recent years. HF remains a significant health concern with an increasing incidence as the population ages. We may indeed be entering the surgical era for HF treatment, but these therapies remain expensive and inaccessible to many. Newer pharmacotherapeutic agents are slowly emerging, many targeting alternative therapeutic pathways, but with mixed results. Metabolic modulation and manipulation of the nitrate/nitrite/nitric oxide pathway have shown promise and could provide the answers to fill the therapeutic gap between medical interventions and surgery, but further definitive trials are warranted. We review the significant evidence base behind the current medical treatments for HFrEF, the physiology of metabolic impairment in HF, and discuss two promising novel agents, perhexiline and nitrite.
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Affiliation(s)
- Brodie L Loudon
- Faculty of Medicine and Health Sciences, University of East Anglia, Norwich, UK
| | - Hannah Noordali
- Institute of Cardiovascular Sciences, University of Birmingham, Birmingham, UK
| | - Nicholas D Gollop
- Faculty of Medicine and Health Sciences, University of East Anglia, Norwich, UK
| | - Michael P Frenneaux
- Faculty of Medicine and Health Sciences, University of East Anglia, Norwich, UK
| | - Melanie Madhani
- Institute of Cardiovascular Sciences, University of Birmingham, Birmingham, UK
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29
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Alzahri MS, Rohra A, Peacock WF. Nitrates as a Treatment of Acute Heart Failure. Card Fail Rev 2016; 2:51-55. [PMID: 28785453 PMCID: PMC5490950 DOI: 10.15420/cfr.2016:3:3] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/04/2016] [Accepted: 04/07/2016] [Indexed: 11/04/2022] Open
Abstract
The purpose of this article is to review the clinical efficacy and safety of nitrates in acute heart failure (AHF) by examining various trials on nitrates in AHF. Management of AHF can be challenging due to the lack of objective clinical evidence guiding optimal management. There have been many articles suggesting that, despite a benefit, nitrates are underused in clinical practice. Nitrates, when appropriately dosed, have a favourable effect on symptoms, blood pressure, intubation rates, mortality and other parameters.
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Affiliation(s)
- Mohammad S Alzahri
- Baylor College of Medicine, Houston, TX, USA
- King Saud University, Riyadh, Saudi Arabia
| | - Anita Rohra
- Baylor College of Medicine, Houston, TX, USA
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30
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Latini R, Masson S, Staszewsky L. Heart failure trials on pharmacological therapy in 2015: lessons learned and future outlook. Expert Rev Cardiovasc Ther 2016; 14:703-11. [DOI: 10.1586/14779072.2016.1159957] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
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31
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Whitfield J, Ludzki A, Heigenhauser GJF, Senden JMG, Verdijk LB, van Loon LJC, Spriet LL, Holloway GP. Beetroot juice supplementation reduces whole body oxygen consumption but does not improve indices of mitochondrial efficiency in human skeletal muscle. J Physiol 2015; 594:421-35. [PMID: 26457670 DOI: 10.1113/jp270844] [Citation(s) in RCA: 73] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2015] [Accepted: 09/29/2015] [Indexed: 12/23/2022] Open
Abstract
KEY POINTS Oral consumption of nitrate (NO3(-)) in beetroot juice has been shown to decrease the oxygen cost of submaximal exercise; however, the mechanism of action remains unresolved. We supplemented recreationally active males with beetroot juice to determine if this altered mitochondrial bioenergetics. Despite reduced submaximal exercise oxygen consumption, measures of mitochondrial coupling and respiratory efficiency were not altered in muscle. In contrast, rates of mitochondrial hydrogen peroxide (H2O2) emission were increased in the absence of markers of lipid or protein oxidative damage. These results suggest that improvements in mitochondrial oxidative metabolism are not the cause of beetroot juice-mediated improvements in whole body oxygen consumption. ABSTRACT Ingestion of sodium nitrate (NO3(-)) simultaneously reduces whole body oxygen consumption (V̇O2) during submaximal exercise while improving mitochondrial efficiency, suggesting a causal link. Consumption of beetroot juice (BRJ) elicits similar decreases in V̇O2 but potential effects on the mitochondria remain unknown. Therefore we examined the effects of 7-day supplementation with BRJ (280 ml day(-1), ∼26 mmol NO3(-)) in young active males (n = 10) who had muscle biopsies taken before and after supplementation for assessments of mitochondrial bioenergetics. Subjects performed 20 min of cycling (10 min at 50% and 70% V̇O2 peak) 48 h before 'Pre' (baseline) and 'Post' (day 5 of supplementation) biopsies. Whole body V̇O2 decreased (P < 0.05) by ∼3% at 70% V̇O2 peak following supplementation. Mitochondrial respiration in permeabilized muscle fibres showed no change in leak respiration, the content of proteins associated with uncoupling (UCP3, ANT1, ANT2), maximal substrate-supported respiration, or ADP sensitivity (apparent Km). In addition, isolated subsarcolemmal and intermyofibrillar mitochondria showed unaltered assessments of mitochondrial efficiency, including ADP consumed/oxygen consumed (P/O ratio), respiratory control ratios and membrane potential determined fluorometrically using Safranine-O. In contrast, rates of mitochondrial hydrogen peroxide (H2O2) emission were increased following BRJ. Therefore, in contrast to sodium nitrate, BRJ supplementation does not alter key parameters of mitochondrial efficiency. This occurred despite a decrease in exercise V̇O2, suggesting that the ergogenic effects of BRJ ingestion are not due to a change in mitochondrial coupling or efficiency. It remains to be determined if increased mitochondrial H2O2 contributes to this response.
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Affiliation(s)
- J Whitfield
- Department of Human Health and Nutritional Sciences, University of Guelph, Guelph, Ontario, Canada, N1G 2W1
| | - A Ludzki
- Department of Human Health and Nutritional Sciences, University of Guelph, Guelph, Ontario, Canada, N1G 2W1
| | - G J F Heigenhauser
- Department of Medicine, McMaster University, Hamilton, Ontario, Canada, L8N 3Z5
| | - J M G Senden
- Department of Human Movement Sciences, Nutrition and Toxicology Research Institute Maastricht (NUTRIM), Maastricht University, 6200 MD, Maastricht, The Netherlands
| | - L B Verdijk
- Department of Human Movement Sciences, Nutrition and Toxicology Research Institute Maastricht (NUTRIM), Maastricht University, 6200 MD, Maastricht, The Netherlands
| | - L J C van Loon
- Department of Human Movement Sciences, Nutrition and Toxicology Research Institute Maastricht (NUTRIM), Maastricht University, 6200 MD, Maastricht, The Netherlands
| | - L L Spriet
- Department of Human Health and Nutritional Sciences, University of Guelph, Guelph, Ontario, Canada, N1G 2W1
| | - G P Holloway
- Department of Human Health and Nutritional Sciences, University of Guelph, Guelph, Ontario, Canada, N1G 2W1
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32
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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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