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Conde SV, Sacramento JF, Zinno C, Mazzoni A, Micera S, Guarino MP. Bioelectronic modulation of carotid sinus nerve to treat type 2 diabetes: current knowledge and future perspectives. Front Neurosci 2024; 18:1378473. [PMID: 38646610 PMCID: PMC11026613 DOI: 10.3389/fnins.2024.1378473] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2024] [Accepted: 03/26/2024] [Indexed: 04/23/2024] Open
Abstract
Bioelectronic medicine are an emerging class of treatments aiming to modulate body nervous activity to correct pathological conditions and restore health. Recently, it was shown that the high frequency electrical neuromodulation of the carotid sinus nerve (CSN), a small branch of the glossopharyngeal nerve that connects the carotid body (CB) to the brain, restores metabolic function in type 2 diabetes (T2D) animal models highlighting its potential as a new therapeutic modality to treat metabolic diseases in humans. In this manuscript, we review the current knowledge supporting the use of neuromodulation of the CSN to treat T2D and discuss the future perspectives for its clinical application. Firstly, we review in a concise manner the role of CB chemoreceptors and of CSN in the pathogenesis of metabolic diseases. Secondly, we describe the findings supporting the potential therapeutic use of the neuromodulation of CSN to treat T2D, as well as the feasibility and reversibility of this approach. A third section is devoted to point up the advances in the neural decoding of CSN activity, in particular in metabolic disease states, that will allow the development of closed-loop approaches to deliver personalized and adjustable treatments with minimal side effects. And finally, we discuss the findings supporting the assessment of CB activity in metabolic disease patients to screen the individuals that will benefit therapeutically from this bioelectronic approach in the future.
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Affiliation(s)
- Silvia V. Conde
- iNOVA4Health, NOVA Medical School, Faculdade de Ciências Médicas, Universidade NOVA de Lisboa, Lisbon, Portugal
| | - Joana F. Sacramento
- iNOVA4Health, NOVA Medical School, Faculdade de Ciências Médicas, Universidade NOVA de Lisboa, Lisbon, Portugal
| | - Ciro Zinno
- The BioRobotics Institute Scuola Superiore Sant’Anna, Pontedera, Italy
| | - Alberto Mazzoni
- The BioRobotics Institute Scuola Superiore Sant’Anna, Pontedera, Italy
| | - Silvestro Micera
- The BioRobotics Institute Scuola Superiore Sant’Anna, Pontedera, Italy
| | - Maria P. Guarino
- ciTechCare, School of Health Sciences Polytechnic of Leiria, Leiria, Portugal
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2
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Lataro RM, Brognara F, Iturriaga R, Paton JFR. Inflammation of some visceral sensory systems and autonomic dysfunction in cardiovascular disease. Auton Neurosci 2024; 251:103137. [PMID: 38104365 DOI: 10.1016/j.autneu.2023.103137] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2023] [Revised: 11/15/2023] [Accepted: 12/04/2023] [Indexed: 12/19/2023]
Abstract
The sensitization and hypertonicity of visceral afferents are highly relevant to the development and progression of cardiovascular and respiratory disease states. In this review, we described the evidence that the inflammatory process regulates visceral afferent sensitivity and tonicity, affecting the control of the cardiovascular and respiratory system. Some inflammatory mediators like nitric oxide, angiotensin II, endothelin-1, and arginine vasopressin may inhibit baroreceptor afferents and contribute to the baroreflex impairment observed in cardiovascular diseases. Cytokines may act directly on peripheral afferent terminals that transmit information to the central nervous system (CNS). TLR-4 receptors, which recognize lipopolysaccharide, were identified in the nodose and petrosal ganglion and have been implicated in disrupting the blood-brain barrier, which can potentiate the inflammatory process. For example, cytokines may cross the blood-brain barrier to access the CNS. Additionally, pro-inflammatory cytokines such as IL-1β, IL-6, TNF-α and some of their receptors have been identified in the nodose ganglion and carotid body. These pro-inflammatory cytokines also sensitize the dorsal root ganglion or are released in the nucleus of the solitary tract. In cardiovascular disease, pro-inflammatory mediators increase in the brain, heart, vessels, and plasma and may act locally or systemically to activate/sensitize afferent nervous terminals. Recent evidence demonstrated that the carotid body chemoreceptor cells might sense systemic pro-inflammatory molecules, supporting the novel proposal that the carotid body is part of the afferent pathway in the central anti-inflammatory reflexes. The exact mechanisms of how pro-inflammatory mediators affects visceral afferent signals and contribute to the pathophysiology of cardiovascular diseases awaits future research.
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Affiliation(s)
- R M Lataro
- Department of Physiological Sciences, Center of Biological Sciences, Federal University of Santa Catarina, Florianópolis, Santa Catarina, Brazil.
| | - F Brognara
- Department of Nursing, General and Specialized, Nursing School of Ribeirão Preto, University of São Paulo, Ribeirão Preto, São Paulo, Brazil
| | - R Iturriaga
- Facultad de Ciencias Biológicas, Pontificia Universidad Catolica de Chile, Santiago, Chile; Centro de Investigación en Fisiología y Medicina en Altura - FIMEDALT, Universidad de Antofagasta, Antofagasta, Chile
| | - J F R Paton
- Manaaki Manawa - The Centre for Heart Research, Department of Physiology, Faculty of Medical & Health Sciences, University of Auckland, Grafton, Auckland, New Zealand
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3
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Felippe ISA, Río RD, Schultz H, Machado BH, Paton JFR. Commonalities and differences in carotid body dysfunction in hypertension and heart failure. J Physiol 2023; 601:5527-5551. [PMID: 37747109 PMCID: PMC10873039 DOI: 10.1113/jp284114] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2023] [Accepted: 08/29/2023] [Indexed: 09/26/2023] Open
Abstract
Carotid body pathophysiology is associated with many cardiovascular-respiratory-metabolic diseases. This pathophysiology reflects both hyper-sensitivity and hyper-tonicity. From both animal models and human patients, evidence indicates that amelioration of this pathophysiological signalling improves disease states such as a lowering of blood pressure in hypertension, a reduction of breathing disturbances with improved cardiac function in heart failure (HF) and a re-balancing of autonomic activity with lowered sympathetic discharge. Given this, we have reviewed the mechanisms of carotid body hyper-sensitivity and hyper-tonicity across disease models asking whether there is uniqueness related to specific disease states. Our analysis indicates some commonalities and some potential differences, although not all mechanisms have been fully explored across all disease models. One potential commonality is that of hypoperfusion of the carotid body across hypertension and HF, where the excessive sympathetic drive may reduce blood flow in both models and, in addition, lowered cardiac output in HF may potentiate the hypoperfusion state of the carotid body. Other mechanisms are explored that focus on neurotransmitter and signalling pathways intrinsic to the carotid body (e.g. ATP, carbon monoxide) as well as extrinsic molecules carried in the blood (e.g. leptin); there are also transcription factors found in the carotid body endothelium that modulate its activity (Krüppel-like factor 2). The evidence to date fully supports that a better understanding of the mechanisms of carotid body pathophysiology is a fruitful strategy for informing potential new treatment strategies for many cardiovascular, respiratory and metabolic diseases, and this is highly relevant clinically.
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Affiliation(s)
- Igor S. A. Felippe
- Manaaki Manawa – The Centre for Heart Research, Department of Physiology, Faculty of Health & Medical Sciences, University of Auckland, Grafton, Auckland, 1023, New Zealand
| | - Rodrigo Del Río
- Department of Physiology, Laboratory of Cardiorespiratory Control, Pontificia Universidad Católica de Chile, Santiago, Chile
- Centro de Excelencia en Biomedicina de Magallanes (CEBIMA), Universidad de Magallanes, Punta Arenas, Chile
- Mechanisms of Myelin Formation and Repair Laboratory, Instituto de Ciencias Biomédicas, Facultad de Ciencias de la Salud, Universidad Autónoma de Chile, Santiago, Chile
- Centro de Envejecimiento y Regeneración (CARE), Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Harold Schultz
- Department of Cellular and Integrative Physiology, University of Nebraska Medical Center, Omaha, Nebraska, USA
| | - Benedito H. Machado
- Department of Physiology, School of Medicine of Ribeirão Preto, University of São Paulo, Ribeirão Preto, São Paulo, Brazil
| | - Julian F. R. Paton
- Manaaki Manawa – The Centre for Heart Research, Department of Physiology, Faculty of Health & Medical Sciences, University of Auckland, Grafton, Auckland, 1023, New Zealand
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4
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Verdoorn D, Cleypool CG, Mackaaij C, Bleys RL. Visualization of the carotid body in situ in fixed human carotid bifurcations using a xylene-based tissue clearing method. Biotech Histochem 2023; 98:166-171. [PMID: 36330775 DOI: 10.1080/10520295.2022.2140831] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The anatomy of the carotid body (CB) and its nerve supply are important, because it is a potential therapeutic target for treatment of various clinical conditions. Visualization of the CB in situ in fixed human anatomical specimens is hampered by obscuring adipose and connective tissues. We developed a tissue clearing method to optimize identification of the CB. We used single sided carotid bifurcations of six human cadavers fixed long term. Visualization of the CB was accomplished by clearing tissue with xylene. Under incident light, carotid bifurcations exhibited a less transparent, darker colored CB; hematoxylin and eosin stained paraffin sections confirmed its identity. Our visualization of the CB in situ in human carotid bifurcations fixed long term enabled targeted resection and subsequent topographic and morphometric measurements of the CB. Our procedure does not interfere with immunohistochemical staining of sections prepared from such specimens.
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Affiliation(s)
- Daphne Verdoorn
- Department of Anatomy, Division of Surgical Specialties, University Medical Center, Utrecht University, Utrecht, The Netherlands
| | - Cindy Gj Cleypool
- Department of Anatomy, Division of Surgical Specialties, University Medical Center, Utrecht University, Utrecht, The Netherlands
| | - Claire Mackaaij
- Department of Anatomy, Division of Surgical Specialties, University Medical Center, Utrecht University, Utrecht, The Netherlands
| | - Ronald Law Bleys
- Department of Anatomy, Division of Surgical Specialties, University Medical Center, Utrecht University, Utrecht, The Netherlands
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Felippe ISA, Zera T, da Silva MP, Moraes DJA, McBryde F, Paton JFR. The sympathetic nervous system exacerbates carotid body sensitivity in hypertension. Cardiovasc Res 2023; 119:316-331. [PMID: 35048948 PMCID: PMC10022867 DOI: 10.1093/cvr/cvac008] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/30/2021] [Revised: 11/24/2021] [Accepted: 01/14/2022] [Indexed: 11/14/2022] Open
Abstract
AIMS The carotid bodies (CBs) of spontaneously hypertensive (SH) rats exhibit hypertonicity and hyperreflexia contributing to heightened peripheral sympathetic outflow. We hypothesized that CB hyperexcitability is driven by its own sympathetic innervation. METHODS AND RESULTS To test this, the chemoreflex was activated (NaCN 50-100 µL, 0.4 µg/µL) in SH and Wistar rats in situ before and after: (i) electrical stimulation (ES; 30 Hz, 2 ms, 10 V) of the superior cervical ganglion (SCG), which innervates the CB; (ii) unilateral resection of the SCG (SCGx); (iii) CB injections of an α1-adrenergic receptor agonist (phenylephrine, 50 µL, 1 mmol/L), and (iv) α1-adrenergic receptor antagonist prazosin (40 µL, 1 mmol/L) or tamsulosin (50 µL, 1 mmol/L). ES of the SCG enhanced CB-evoked sympathoexcitation by 40-50% (P < 0.05) with no difference between rat strains. Unilateral SCGx attenuated the CB-evoked sympathoexcitation in SH (62%; P < 0.01) but was without effect in Wistar rats; it also abolished the ongoing firing of chemoreceptive petrosal neurones of SH rats, which became hyperpolarized. In Wistar rats, CB injections of phenylephrine enhanced CB-evoked sympathoexcitation (33%; P < 0.05), which was prevented by prazosin (26%; P < 0.05) in SH rats. Tamsulosin alone reproduced the effects of prazosin in SH rats and prevented the sensitizing effect of the SCG following ES. Within the CB, α1A- and α1B-adrenoreceptors were co-localized on both glomus cells and blood vessels. In conscious SH rats instrumented for recording blood pressure (BP), the CB-evoked pressor response was attenuated after SCGx, and systolic BP fell by 16 ± 4.85 mmHg. CONCLUSIONS The sympathetic innervation of the CB is tonically activated and sensitizes the CB of SH but not Wistar rats. Furthermore, sensitization of CB-evoked reflex sympathoexcitation appears to be mediated by α1-adrenoceptors located either on the vasculature and/or glomus cells. The SCG is novel target for controlling CB pathophysiology in hypertension.
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Affiliation(s)
- Igor S A Felippe
- Department of Physiology, Faculty of Health & Medical Sciences, Manaaki Mānawa—The Centre for Heart Research, University of Auckland, 85 Park Road, Grafton Campus, Auckland 1023, New Zealand
| | - Tymoteusz Zera
- Department of Experimental and Clinical Physiology, Laboratory of Centre for Preclinical Research, Medical University of Warsaw, Warsaw 02-091, Poland
| | - Melina P da Silva
- Department of Physiology, School of Medicine of Ribeirão Preto, University of São Paulo, Ribeirão Preto, SP 14040-900, Brazil
| | - Davi J A Moraes
- Department of Physiology, School of Medicine of Ribeirão Preto, University of São Paulo, Ribeirão Preto, SP 14040-900, Brazil
| | - Fiona McBryde
- Department of Physiology, Faculty of Health & Medical Sciences, Manaaki Mānawa—The Centre for Heart Research, University of Auckland, 85 Park Road, Grafton Campus, Auckland 1023, New Zealand
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Neder JA, Phillips DB, O'Donnell DE, Dempsey JA. Excess ventilation and exertional dyspnoea in heart failure and pulmonary hypertension. Eur Respir J 2022; 60:13993003.00144-2022. [PMID: 35618273 DOI: 10.1183/13993003.00144-2022] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2022] [Accepted: 05/05/2022] [Indexed: 01/11/2023]
Abstract
Increased ventilation relative to metabolic demands, indicating alveolar hyperventilation and/or increased physiological dead space (excess ventilation), is a key cause of exertional dyspnoea. Excess ventilation has assumed a prominent role in the functional assessment of patients with heart failure (HF) with reduced (HFrEF) or preserved (HFpEF) ejection fraction, pulmonary arterial hypertension (PAH) and chronic thromboembolic pulmonary hypertension (CTEPH). We herein provide the key pieces of information to the caring physician to 1) gain unique insights into the seeds of patients' shortness of breath and 2) develop a rationale for therapeutically lessening excess ventilation to mitigate this distressing symptom. Reduced bulk oxygen transfer induced by cardiac output limitation and/or right ventricle-pulmonary arterial uncoupling increase neurochemical afferent stimulation and (largely chemo-) receptor sensitivity, leading to alveolar hyperventilation in HFrEF, PAH and small-vessel, distal CTEPH. As such, interventions geared to improve central haemodynamics and/or reduce chemosensitivity have been particularly effective in lessening their excess ventilation. In contrast, 1) high filling pressures in HFpEF and 2) impaired lung perfusion leading to ventilation/perfusion mismatch in proximal CTEPH conspire to increase physiological dead space. Accordingly, 1) decreasing pulmonary capillary pressures and 2) mechanically unclogging larger pulmonary vessels (pulmonary endarterectomy and balloon pulmonary angioplasty) have been associated with larger decrements in excess ventilation. Exercise training has a strong beneficial effect across diseases. Addressing some major unanswered questions on the link of excess ventilation with exertional dyspnoea under the modulating influence of pharmacological and nonpharmacological interventions might prove instrumental to alleviate the devastating consequences of these prevalent diseases.
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Affiliation(s)
- J Alberto Neder
- Clinical Exercise Physiology and Respiratory Investigation Unit, Division of Respiratory and Critical Care Medicine, Dept of Medicine, Queen's University and Kingston Health Sciences Centre, Kingston, ON, Canada
| | - Devin B Phillips
- Clinical Exercise Physiology and Respiratory Investigation Unit, Division of Respiratory and Critical Care Medicine, Dept of Medicine, Queen's University and Kingston Health Sciences Centre, Kingston, ON, Canada
| | - Denis E O'Donnell
- Clinical Exercise Physiology and Respiratory Investigation Unit, Division of Respiratory and Critical Care Medicine, Dept of Medicine, Queen's University and Kingston Health Sciences Centre, Kingston, ON, Canada
| | - Jerome A Dempsey
- John Rankin Laboratory of Pulmonary Medicine, Dept of Population Health Sciences, University of Wisconsin-Madison, Madison, WI, USA
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7
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Kious KW, Philipose A, Smith LJ, Kemble JP, Twohey SCE, Savage K, Díaz HS, Del Rio R, Marcus NJ. Peripheral chemoreflex modulation of renal hemodynamics and renal tissue PO2 in chronic heart failure with reduced ejection fraction. Front Physiol 2022; 13:955538. [PMID: 36091359 PMCID: PMC9459040 DOI: 10.3389/fphys.2022.955538] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2022] [Accepted: 07/25/2022] [Indexed: 11/13/2022] Open
Abstract
Aberrant carotid body chemoreceptor (CBC) function contributes to increased sympathetic nerve activity (SNA) and reduced renal blood flow (RBF) in chronic heart failure (CHF). Intermittent asphyxia (IA) mimicking sleep apnea is associated with additional increases in SNA and may worsen reductions in RBF and renal PO2 (RPO2) in CHF. The combined effects of decreased RBF and RPO2 may contribute to biochemical changes precipitating renal injury. This study sought to determine the role of CBC activity on glomerular filtration rate (GFR), RBF and RPO2 in CHF, and to assess the additive effects of IA. Furthermore, we sought to identify changes in gene expression that might contribute to renal injury. We hypothesized that GFR, RBF, and RPO2 would be reduced in CHF, that decreases in RBF and RPO2 would be worsened by IA, and that these changes would be ameliorated by CBC ablation (CBD). Finally, we hypothesized that CHF would be associated with pro-oxidative pro-fibrotic changes in renal gene expression that would be ameliorated by CBD. CHF was induced in adult male Sprague Dawley rats using coronary artery ligation (CAL). Carotid body denervation was performed by cryogenic ablation. GFR was assessed in conscious animals at the beginning and end of the experimental period. At 8-weeks post-CAL, cardiac function was assessed via echocardiography, and GFR, baseline and IA RBF and RPO2 were measured. Renal gene expression was measured using qRT-PCR. GFR was lower in CHF compared to sham (p < 0.05) but CBD had no salutary effect. RBF and RPO2 were decreased in CHF compared to sham (p < 0.05), and this effect was attenuated by CBD (p < 0.05). RBF and RPO2 were reduced to a greater extent in CHF vs. sham during exposure to IA (p < 0.05), and this effect was attenuated by CBD for RBF (p < 0.05). Downregulation of antioxidant defense and fibrosis-suppressing genes was observed in CHF vs. sham however CBD had no salutary effect. These results suggest that aberrant CBC function in CHF has a clear modulatory effect on RBF during normoxia and during IA simulating central sleep apnea.
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Affiliation(s)
- Kiefer W. Kious
- Department of Physiology and Pharmacology, Des Moines University Medicine and Health Sciences, Des Moines, IA, United States
| | - Andrew Philipose
- Department of Physiology and Pharmacology, Des Moines University Medicine and Health Sciences, Des Moines, IA, United States
| | - Luke J. Smith
- Department of Physiology and Pharmacology, Des Moines University Medicine and Health Sciences, Des Moines, IA, United States
| | - Jayson P. Kemble
- Department of Physiology and Pharmacology, Des Moines University Medicine and Health Sciences, Des Moines, IA, United States
| | - Stephanie C. E. Twohey
- Department of Physiology and Pharmacology, Des Moines University Medicine and Health Sciences, Des Moines, IA, United States
- Department of Biology, Simpson College, Indianola, IA, United States
| | - Kalie Savage
- Department of Physiology and Pharmacology, Des Moines University Medicine and Health Sciences, Des Moines, IA, United States
| | - Hugo S. Díaz
- Laboratory of Cardiorespiratory Control, Department of Physiology, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Rodrigo Del Rio
- Laboratory of Cardiorespiratory Control, Department of Physiology, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Noah J. Marcus
- Department of Physiology and Pharmacology, Des Moines University Medicine and Health Sciences, Des Moines, IA, United States
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8
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Deep Singh T. Abnormal Sleep-Related Breathing Related to Heart Failure. Sleep Med Clin 2022; 17:87-98. [PMID: 35216764 DOI: 10.1016/j.jsmc.2021.10.007] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
Abstract
Sleep-disordered breathing (SDB) is highly prevalent in patients with heart failure (HF). Untreated obstructive sleep apnea (OSA) and central sleep apnea (CSA) in patients with HF are associated with worse outcomes. Detailed sleep history along with polysomnography (PSG) should be conducted if SDB is suspected in patients with HF. First line of treatment is the optimization of medical therapy for HF and if symptoms persist despite optimization of the treatment, positive airway pressure (PAP) therapy will be started to treat SDB. At present, there is limited evidence to prescribe any drugs for treating CSA in patients with HF. There is limited evidence for the efficacy of continuous positive airway pressure (CPAP) or adaptive servo-ventilation (ASV) in improving mortality in patients with heart failure with reduced ejection fraction (HFrEF). There is a need to perform well-designed studies to identify different phenotypes of CSA/OSA in patients with HF and to determine which phenotype responds to which therapy. Results of ongoing trials, ADVENT-HF, and LOFT-HF are eagerly awaited to shed more light on the management of CSA in patients with HF. Until then the management of SDB in patients with HF is limited due to the lack of evidence and guidance for treating SDB in patients with HF.
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Affiliation(s)
- Tripat Deep Singh
- Academy of Sleep Wake Science, #32 St.no-9 Guru Nanak Nagar, near Gurbax Colony, Patiala, Punjab, India 147003.
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9
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Jorbenadze A, Fudim M, Mahfoud F, Adamson PB, Bekfani T, Wachter R, Sievert H, Ponikowski PP, Cleland JGF, Anker SD. Extra-cardiac targets in the management of cardiometabolic disease: Device-based therapies. ESC Heart Fail 2021; 8:3327-3338. [PMID: 34002946 PMCID: PMC8318435 DOI: 10.1002/ehf2.13361] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2021] [Revised: 03/14/2021] [Accepted: 03/29/2021] [Indexed: 12/14/2022] Open
Abstract
Heart failure (HF) does not occur in a vacuum and is commonly defined and exacerbated by its co‐morbid conditions. Neurohormonal imbalance and systemic inflammation are some of the key pathomechanisms of HF but also commonly encountered co‐morbidities such as arterial hypertension, diabetes mellitus, cachexia, obesity and sleep‐disordered breathing. A cornerstone of HF management is neurohormonal blockade, which in HF with reduced ejection fraction has been tied to a reduction in morbidity and mortality. Pharmacological treatment effective in patients with HF with reduced ejection fraction did not show substantial effects in HF with preserved ejection fraction. Here, we review novel device‐based therapies using neuromodulation of extra‐cardiac targets to treat cardiometabolic disease.
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Affiliation(s)
| | - Marat Fudim
- Division of Cardiology, Duke University Medical Center, Durham, NC, USA.,Duke Clinical Research Institute, Durham, NC, USA
| | - Felix Mahfoud
- Department of Internal Medicine III, Cardiology, Angiology, and Intensive Care Medicine, Saarland University, Saarbrücken, Germany
| | | | - Tarek Bekfani
- Department of Internal Medicine I, Division of Cardiology, Angiology and Intensive Medical Care, University Hospital Magdeburg, Otto von Guericke University, Magdeburg, Germany
| | - Rolf Wachter
- Clinic and Polyclinic for Cardiology, University Hospital Leipzig, Leipzig, Germany
| | | | | | - John G F Cleland
- Robertson Centre for Biostatistics, University of Glasgow, Glasgow, UK
| | - Stefan D Anker
- Division of Cardiology and Metabolism - Heart Failure, Cachexia & Sarcopenia, Department of Cardiology, Campus Virchow-Klinikum, Charité - Universitätsmedizin Berlin, Berlin, Germany.,Berlin-Brandenburg Centre for Regenerative Therapies (BCRT), Charité - Universitätsmedizin Berlin, Berlin, Germany
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10
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Keir DA, Duffin J, Floras JS. Measuring Peripheral Chemoreflex Hypersensitivity in Heart Failure. Front Physiol 2020; 11:595486. [PMID: 33447244 PMCID: PMC7802759 DOI: 10.3389/fphys.2020.595486] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2020] [Accepted: 11/30/2020] [Indexed: 01/08/2023] Open
Abstract
Heart failure with reduced ejection fraction (HFrEF) induces chronic sympathetic activation. This disturbance is a consequence of both compensatory reflex disinhibition in response to lower cardiac output and patient-specific activation of one or more excitatory stimuli. The result is the net adrenergic output that exceeds homeostatic need, which compromises cardiac, renal, and vascular function and foreshortens lifespan. One such sympatho-excitatory mechanism, evident in ~40-45% of those with HFrEF, is the augmentation of carotid (peripheral) chemoreflex ventilatory and sympathetic responsiveness to reductions in arterial oxygen tension and acidosis. Recognition of the contribution of increased chemoreflex gain to the pathophysiology of HFrEF and to patients' prognosis has focused attention on targeting the carotid body to attenuate sympathetic drive, alleviate heart failure symptoms, and prolong life. The current challenge is to identify those patients most likely to benefit from such interventions. Two assumptions underlying contemporary test protocols are that the ventilatory response to acute hypoxic exposure quantifies accurately peripheral chemoreflex sensitivity and that the unmeasured sympathetic response mirrors the determined ventilatory response. This Perspective questions both assumptions, illustrates the limitations of conventional transient hypoxic tests for assessing peripheral chemoreflex sensitivity and demonstrates how a modified rebreathing test capable of comprehensively quantifying both the ventilatory and sympathoneural efferent responses to peripheral chemoreflex perturbation, including their sensitivities and recruitment thresholds, can better identify individuals most likely to benefit from carotid body intervention.
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Affiliation(s)
- Daniel A. Keir
- University Health Network and Mount Sinai Hospital Division of Cardiology and Department of Medicine, University of Toronto, Toronto General Research Institute, Toronto, ON, Canada
- School of Kinesiology, The University of Western Ontario, London, ON, Canada
| | - James Duffin
- Department of Anesthesia and Pain Management, University of Toronto, Toronto, ON, Canada
- Department of Physiology, University of Toronto, Toronto, ON, Canada
- Thornhill Research Inc., Toronto, ON, Canada
| | - John S. Floras
- University Health Network and Mount Sinai Hospital Division of Cardiology and Department of Medicine, University of Toronto, Toronto General Research Institute, Toronto, ON, Canada
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11
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Macchione AF, Trujillo V, Anunziata F, Sahonero M, Anastasia A, Abate P, Molina JC. Early ethanol pre-exposure alters breathing patterns by disruptions in the central respiratory network and serotonergic balance in neonate rats. Behav Brain Res 2020; 396:112908. [PMID: 32961215 DOI: 10.1016/j.bbr.2020.112908] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2020] [Revised: 08/04/2020] [Accepted: 09/13/2020] [Indexed: 10/23/2022]
Abstract
Early ethanol exposure alters neonatal breathing plasticity. Respiratory EtOH's effects are attributed to central respiratory network disruptions, particularly in the medullary serotonin (5HT) system. In this study we evaluated the effects of neonatal pre-exposure to low/moderate doses upon breathing rates, activation patterns of brainstem's nuclei and expression of 5HT 2A and 2C receptors. At PD9, breathing frequencies, tidal volumes and apneas were examined in pups pre-exposed to vehicle or ethanol (2.0 g/kg) at PDs 3, 5 and 7. This developmental stage is equivalent to the 3rd human gestational trimester, characterized by increased levels of synaptogenesis. Pups were tested under sobriety or under the state of ethanol intoxication and when subjected to normoxia or hypoxia. Number of c-Fos and 5HT immunolabelled cells and relative mRNA expression of 5HT 2A and 2C receptors were quantified in the brainstem. Under normoxia, ethanol pre-exposed pups exhibited breathing depressions and a high number of apneas. An opposite phenomenon was found in ethanol pre-treated pups tested under hypoxia where an exacerbated hypoxic ventilatory response (HVR) was observed. The breathing depression was associated with an increase in the neural activation levels of the raphe obscurus (ROb) and a high mRNA expression of the 5HT 2A receptor in the brainstem while desactivation of the ROb and high activation levels in the solitary tract nucleus and area postrema were associated to the exacerbated HVR. In summary, early ethanol experience induces respiratory disruptions indicative of sensitization processes. Neuroadaptive changes in central respiratory areas under consideration appear to be strongly associated with changes in their respiratory plasticity.
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Affiliation(s)
- A F Macchione
- Instituto De Investigación Médica Mercedes y Martín Ferreyra, INIMEC-CONICET- Universidad Nacional De Córdoba, Córdoba, Argentina; Facultad De Psicología, Universidad Nacional De Córdoba, Córdoba, Argentina; Instituto De Investigaciones Psicológicas, IIPsi-CONICET-Universidad Nacional De Córdoba, Córdoba, Argentina.
| | - V Trujillo
- Instituto De Investigación Médica Mercedes y Martín Ferreyra, INIMEC-CONICET- Universidad Nacional De Córdoba, Córdoba, Argentina
| | - F Anunziata
- Instituto De Investigación Médica Mercedes y Martín Ferreyra, INIMEC-CONICET- Universidad Nacional De Córdoba, Córdoba, Argentina
| | - M Sahonero
- Facultad De Psicología, Universidad Nacional De Córdoba, Córdoba, Argentina
| | - A Anastasia
- Instituto De Investigación Médica Mercedes y Martín Ferreyra, INIMEC-CONICET- Universidad Nacional De Córdoba, Córdoba, Argentina; Facultad De Psicología, Universidad Nacional De Córdoba, Córdoba, Argentina
| | - P Abate
- Facultad De Psicología, Universidad Nacional De Córdoba, Córdoba, Argentina; Instituto De Investigaciones Psicológicas, IIPsi-CONICET-Universidad Nacional De Córdoba, Córdoba, Argentina
| | - J C Molina
- Instituto De Investigación Médica Mercedes y Martín Ferreyra, INIMEC-CONICET- Universidad Nacional De Córdoba, Córdoba, Argentina; Facultad De Psicología, Universidad Nacional De Córdoba, Córdoba, Argentina.
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12
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Brognara F, Felippe ISA, Salgado HC, Paton JFR. Autonomic innervation of the carotid body as a determinant of its sensitivity: implications for cardiovascular physiology and pathology. Cardiovasc Res 2020; 117:1015-1032. [PMID: 32832979 DOI: 10.1093/cvr/cvaa250] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/18/2020] [Revised: 07/01/2020] [Accepted: 08/18/2020] [Indexed: 12/14/2022] Open
Abstract
The motivation for this review comes from the emerging complexity of the autonomic innervation of the carotid body (CB) and its putative role in regulating chemoreceptor sensitivity. With the carotid bodies as a potential therapeutic target for numerous cardiorespiratory and metabolic diseases, an understanding of the neural control of its circulation is most relevant. Since nerve fibres track blood vessels and receive autonomic innervation, we initiate our review by describing the origins of arterial feed to the CB and its unique vascular architecture and blood flow. Arterial feed(s) vary amongst species and, unequivocally, the arterial blood supply is relatively high to this organ. The vasculature appears to form separate circuits inside the CB with one having arterial venous anastomoses. Both sympathetic and parasympathetic nerves are present with postganglionic neurons located within the CB or close to it in the form of paraganglia. Their role in arterial vascular resistance control is described as is how CB blood flow relates to carotid sinus afferent activity. We discuss non-vascular targets of autonomic nerves, their possible role in controlling glomus cell activity, and how certain transmitters may relate to function. We propose that the autonomic nerves sub-serving the CB provide a rapid mechanism to tune the gain of peripheral chemoreflex sensitivity based on alterations in blood flow and oxygen delivery, and might provide future therapeutic targets. However, there remain a number of unknowns regarding these mechanisms that require further research that is discussed.
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Affiliation(s)
- Fernanda Brognara
- Department of Physiology, Faculty of Medical and Health Sciences, University of Auckland, 85 Park Road, Grafton Auckland 1023, New Zealand.,Department of Physiology, Ribeirão Preto Medical School, University of São Paulo, Ribeirão Preto, São Paulo, Brazil
| | - Igor S A Felippe
- Department of Physiology, Faculty of Medical and Health Sciences, University of Auckland, 85 Park Road, Grafton Auckland 1023, New Zealand
| | - Helio C Salgado
- Department of Physiology, Ribeirão Preto Medical School, University of São Paulo, Ribeirão Preto, São Paulo, Brazil
| | - Julian F R Paton
- Department of Physiology, Faculty of Medical and Health Sciences, University of Auckland, 85 Park Road, Grafton Auckland 1023, New Zealand
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13
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Precision Targeted Ablation of Fine Neurovascular Structures In Vivo Using Dual-mode Ultrasound Arrays. Sci Rep 2020; 10:9249. [PMID: 32514058 PMCID: PMC7280193 DOI: 10.1038/s41598-020-66209-0] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2019] [Accepted: 05/18/2020] [Indexed: 12/14/2022] Open
Abstract
Carotid bodies (CBs) are chemoreceptors that monitor and register changes in the blood, including the levels of oxygen, carbon dioxide, and pH, and regulate breathing. Enhanced activity of CBs was shown to correlate with a significant elevation in the blood pressure of patients with hypertension. CB removal or denervation were previously shown to reduce hypertension. Here we demonstrate the feasibility of a dual-mode ultrasound array (DMUA) system to safely ablate the CB in vivo in a spontaneously hypertensive rat (SHR) model of hypertension. DMUA imaging was used for guiding and monitoring focused ultrasound (FUS) energy delivered to the target region. In particular, 3D imaging was used to identify the carotid bifurcation for targeting the CBs. Intermittent, high frame rate imaging during image-guided FUS (IgFUS) delivery was used for monitoring the lesion formation. DMUA imaging provided feedback for closed-loop control (CLC) of the lesion formation process to avoid overexposure. The procedure was tolerated well in over 100 SHR and normotensive rats that received unilateral and bilateral treatments. The measured mean arterial pressure (MAP) exhibited measurable deviation from baseline 2–4 weeks post IgFUS treatment. The results suggest that the direct unilateral FUS treatment of the CB might be sufficient to reduce the blood pressure in hypertensive rats and justify further investigation in large animals and eventually in human patients.
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14
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Javaheri S, Brown LK, Khayat RN. Update on Apneas of Heart Failure With Reduced Ejection Fraction: Emphasis on the Physiology of Treatment. Chest 2020; 157:1637-1646. [DOI: 10.1016/j.chest.2019.12.020] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2019] [Revised: 12/17/2019] [Accepted: 12/31/2019] [Indexed: 02/07/2023] Open
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15
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Machado AC, Vianna LC, Gomes EAC, Teixeira JAC, Ribeiro ML, Villacorta H, Nobrega ACL, Silva BM. Carotid chemoreflex and muscle metaboreflex interact to the regulation of ventilation in patients with heart failure with reduced ejection fraction. Physiol Rep 2020; 8:e14361. [PMID: 32026605 PMCID: PMC7002537 DOI: 10.14814/phy2.14361] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2019] [Revised: 01/06/2020] [Accepted: 01/07/2020] [Indexed: 01/16/2023] Open
Abstract
Synergism among reflexes probably contributes to exercise hyperventilation in patients with heart failure with reduced ejection fraction (HFrEF). Thus, we investigated whether the carotid chemoreflex and the muscle metaboreflex interact to the regulation of ventilation ( V ˙ E ) in HFrEF. Ten patients accomplished 4-min cycling at 60% peak workload and then recovered for 2 min under either: (a) 21% O2 inhalation (tonic carotid chemoreflex activity) with legs' circulation free (inactive muscle metaboreflex); (b) 100% O2 inhalation (suppressed carotid chemoreflex activity) with legs' circulation occluded (muscle metaboreflex activation); (c) 21% O2 inhalation (tonic carotid chemoreflex activity) with legs' circulation occluded (muscle metaboreflex activation); or (d) 100% O2 inhalation (suppressed carotid chemoreflex activity) with legs' circulation free (inactive muscle metaboreflex) as control. V ˙ E , tidal volume (VT ) and respiratory frequency (fR ) were similar between each separated reflex (protocols a and b) and control (protocol d). Calculated sum of separated reflexes effects was similar to control. Oppositely, V ˙ E (mean ± SEM: Δ vs. control = 2.46 ± 1.07 L/min, p = .05) and fR (Δ = 2.47 ± 0.77 cycles/min, p = .02) increased versus control when both reflexes were simultaneously active (protocol c). Therefore, the carotid chemoreflex and the muscle metaboreflex interacted to V ˙ E regulation in a fR -dependent manner in patients with HFrEF. If this interaction operates during exercise, it can have some contribution to the HFrEF exercise hyperventilation.
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Affiliation(s)
- Alessandro C. Machado
- Laboratory of Exercise SciencesDepartment of Physiology and PharmacologyFluminense Federal UniversityNiteróiRJBrazil
- Latin American Institute of Life and Nature SciencesFederal University of Latin American IntegrationFoz do IguaçuPRBrazil
| | - Lauro C. Vianna
- Faculty of Physical EducationUniversity of BrasíliaBrasiliaDFBrazil
| | - Erika A. C. Gomes
- Laboratory of Exercise SciencesDepartment of Physiology and PharmacologyFluminense Federal UniversityNiteróiRJBrazil
| | - Jose A. C. Teixeira
- Antonio Pedro University HospitalFaculty of MedicineFluminense Federal UniversityNiteróiRJBrazil
| | - Mario L. Ribeiro
- Antonio Pedro University HospitalFaculty of MedicineFluminense Federal UniversityNiteróiRJBrazil
| | - Humberto Villacorta
- Antonio Pedro University HospitalFaculty of MedicineFluminense Federal UniversityNiteróiRJBrazil
| | - Antonio C. L. Nobrega
- Laboratory of Exercise SciencesDepartment of Physiology and PharmacologyFluminense Federal UniversityNiteróiRJBrazil
| | - Bruno M. Silva
- Department of PhysiologyFederal University of São PauloSão PauloSPBrazil
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16
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Heusser K, Thöne A, Lipp A, Menne J, Beige J, Reuter H, Hoffmann F, Halbach M, Eckert S, Wallbach M, Koziolek M, Haarmann H, Joyner MJ, Paton JFR, Diedrich A, Haller H, Jordan J, Tank J. Efficacy of Electrical Baroreflex Activation Is Independent of Peripheral Chemoreceptor Modulation. Hypertension 2019; 75:257-264. [PMID: 31786986 DOI: 10.1161/hypertensionaha.119.13925] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Arterial baroreflex activation through electrical carotid sinus stimulation has been developed for the treatment of resistant hypertension. Previous studies suggested that the peripheral chemoreflex is tonically active in hypertensive patients and may inhibit baroreflex responses. We hypothesized that peripheral chemoreflex activation attenuates baroreflex efficacy evoked by electrical carotid sinus stimulation. We screened 35 patients with an implanted electrical carotid sinus stimulator. Of those, 11 patients with consistent acute depressor response were selected (7 men/4 women, age: 67±8 years, body mass index: 31.6±5.2 kg/m2, 6±2 antihypertensive drug classes). We assessed responses to electrical baroreflex stimulation during normoxia, isocapnic hypoxia (SpO2: 79.0±1.5%), and hyperoxia (40% end-tidal O2 fraction) by measuring heart rate, blood pressure, ventilation, oxygen saturation, end-tidal CO2 and O2 fractions, and muscle sympathetic nerve activity. During normoxia, baroreflex activation reduced systolic blood pressure from 164±27 to 151±25 mm Hg (mean±SD, P<0.001), heart rate from 64±13 to 61±13 bpm (P=0.002), and muscle sympathetic nerve activity from 42±12 to 36±12 bursts/min (P=0.004). Hypoxia increased systolic blood pressure 8±12 mm Hg (P=0.057), heart rate 10±6 bpm (P<0.001), muscle sympathetic nerve activity 7±7 bursts/min (P=0.031), and ventilation 10±7 L/min (P=0.002). However, responses to electrical carotid sinus stimulation did not differ between hypoxic and hyperoxic conditions: systolic blood pressure: -15±7 versus -14±8 mm Hg (P=0.938), heart rate: -2±3 versus -2±2 bpm (P=0.701), and muscle sympathetic nerve activity: -6±4 versus -4±3 bursts/min (P=0.531). We conclude that moderate peripheral chemoreflex activation does not attenuate acute responses to electrical baroreflex activation therapy in patients with resistant hypertension. These patients provided insight into human baroreflex-chemoreflex interactions that could not be gained otherwise.
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Affiliation(s)
- Karsten Heusser
- From the Institute of Aerospace Medicine, German Aerospace Center, Cologne, Germany (K.H., F.H., J.J., J.T.)
| | | | - Axel Lipp
- Department of Neurology, Park Clinic Weissensee, Berlin, Germany (A.L.)
| | - Jan Menne
- Department of Nephrology and Hypertensiology, Hannover Medical School, Germany (J.M., H. Haller)
| | - Joachim Beige
- Department of Nephrology and KfH Renal Unit, Hospital St. Georg, Leipzig, Germany (J.B.).,Faculty of Medicine, Martin Luther University Halle/Wittenberg, Germany (J.B.)
| | - Hannes Reuter
- Department of Cardiology, Pneumology, and Angiology, Heart Center of the University of Cologne, Germany (H.R., F.H., M.H.).,Department of Internal Medicine, Ev. Klinikum Köln Weyertal, Cologne, Germany (H.R.)
| | - Fabian Hoffmann
- From the Institute of Aerospace Medicine, German Aerospace Center, Cologne, Germany (K.H., F.H., J.J., J.T.).,Department of Cardiology, Pneumology, and Angiology, Heart Center of the University of Cologne, Germany (H.R., F.H., M.H.)
| | - Marcel Halbach
- Department of Cardiology, Pneumology, and Angiology, Heart Center of the University of Cologne, Germany (H.R., F.H., M.H.)
| | - Siegfried Eckert
- Department of Cardiology, Heart and Diabetes Centre North Rhine-Westphalia, University Hospital, Ruhr University Bochum, Bad Oeynhausen, Germany (S.E.)
| | - Manuel Wallbach
- Department of Nephrology & Rheumatology (M.W., M.K.), University Medical Center Göttingen, Germany
| | - Michael Koziolek
- Department of Nephrology & Rheumatology (M.W., M.K.), University Medical Center Göttingen, Germany
| | - Helge Haarmann
- Clinic for Cardiology and Pneumology (H.Haarmann), University Medical Center Göttingen, Germany
| | - Michael J Joyner
- Department of Anesthesiology, Mayo Clinic, Rochester, MN (M.J.J.)
| | - Julian F R Paton
- School of Physiology, Pharmacology, and Neuroscience, University of Bristol, United Kingdom (J.F.R.P.).,Department of Physiology, University of Auckland, Grafton, New Zealand (J.F.R.P.)
| | - André Diedrich
- Department of Medicine, Division of Clinical Pharmacology, Autonomic Dysfunction Center, Vanderbilt University Medical Center, Nashville, TN (A.D.)
| | - Hermann Haller
- Department of Nephrology and Hypertensiology, Hannover Medical School, Germany (J.M., H. Haller)
| | - Jens Jordan
- From the Institute of Aerospace Medicine, German Aerospace Center, Cologne, Germany (K.H., F.H., J.J., J.T.)
| | - Jens Tank
- From the Institute of Aerospace Medicine, German Aerospace Center, Cologne, Germany (K.H., F.H., J.J., J.T.)
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17
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Keir DA, Duffin J, Millar PJ, Floras JS. Simultaneous assessment of central and peripheral chemoreflex regulation of muscle sympathetic nerve activity and ventilation in healthy young men. J Physiol 2019; 597:3281-3296. [DOI: 10.1113/jp277691] [Citation(s) in RCA: 32] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2019] [Accepted: 05/13/2019] [Indexed: 12/20/2022] Open
Affiliation(s)
- Daniel A. Keir
- University Health Network and Mount Sinai Hospital Division of CardiologyDepartment of Medicine, University of Toronto Toronto Ontario Canada
| | - James Duffin
- Departments of Anaesthesia and PhysiologyUniversity of Toronto Toronto Ontario Canada
- Thornhill Research Inc. Toronto Ontario Canada
| | - Philip J. Millar
- University Health Network and Mount Sinai Hospital Division of CardiologyDepartment of Medicine, University of Toronto Toronto Ontario Canada
- Human Health and Nutritional ScienceUniversity of Guelph Guelph Ontario Canada
| | - John S. Floras
- University Health Network and Mount Sinai Hospital Division of CardiologyDepartment of Medicine, University of Toronto Toronto Ontario Canada
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18
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Porzionato A, Macchi V, Stecco C, De Caro R. The Carotid Sinus Nerve-Structure, Function, and Clinical Implications. Anat Rec (Hoboken) 2018; 302:575-587. [PMID: 29663677 DOI: 10.1002/ar.23829] [Citation(s) in RCA: 39] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2017] [Revised: 06/24/2017] [Accepted: 08/01/2017] [Indexed: 12/12/2022]
Abstract
Interest has been renewed in the anatomy and physiology of the carotid sinus nerve (CSN) and its targets (carotid sinus and carotid body, CB), due to recent proposals of surgical procedures for a series of common pathologies, such as carotid sinus syndrome, hypertension, heart failure, and insulin resistance. The CSN originates from the glossopharyngeal nerve soon after its appearance from the jugular foramen. It shows frequent communications with the sympathetic trunk (usually at the level of the superior cervical ganglion) and the vagal nerve (main trunk, pharyngeal branches, or superior laryngeal nerve). It courses on the anterior aspect of the internal carotid artery to reach the carotid sinus, CB, and/or intercarotid plexus. In the carotid sinus, type I (dynamic) carotid baroreceptors have larger myelinated A-fibers; type II (tonic) baroreceptors show smaller A- and unmyelinated C-fibers. In the CB, afferent fibers are mainly stimulated by acetylcholine and ATP, released by type I cells. The neurons are located in the petrosal ganglion, and centripetal fibers project on to the solitary tract nucleus: chemosensory inputs to the commissural subnucleus, and baroreceptor inputs to the commissural, medial, dorsomedial, and dorsolateral subnuclei. The baroreceptor component of the CSN elicits sympatho-inhibition and the chemoreceptor component stimulates sympatho-activation. Thus, in refractory hypertension and heart failure (characterized by increased sympathetic activity), baroreceptor electrical stimulation, and CB removal have been proposed. Instead, denervation of the carotid sinus has been proposed for the "carotid sinus syndrome." Anat Rec, 302:575-587, 2019. © 2018 Wiley Periodicals, Inc.
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Affiliation(s)
- Andrea Porzionato
- Department of Neuroscience, Institute of Human Anatomy, University of Padova, Padova, Italy
| | - Veronica Macchi
- Department of Neuroscience, Institute of Human Anatomy, University of Padova, Padova, Italy
| | - Carla Stecco
- Department of Neuroscience, Institute of Human Anatomy, University of Padova, Padova, Italy
| | - Raffaele De Caro
- Department of Neuroscience, Institute of Human Anatomy, University of Padova, Padova, Italy
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19
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Naeije R, Faoro V. The breathlessness of pulmonary hypertension. Int J Cardiol 2018; 259:183-184. [DOI: 10.1016/j.ijcard.2017.12.018] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/01/2017] [Accepted: 12/05/2017] [Indexed: 10/17/2022]
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20
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Sacramento JF, Chew DJ, Melo BF, Donegá M, Dopson W, Guarino MP, Robinson A, Prieto-Lloret J, Patel S, Holinski BJ, Ramnarain N, Pikov V, Famm K, Conde SV. Bioelectronic modulation of carotid sinus nerve activity in the rat: a potential therapeutic approach for type 2 diabetes. Diabetologia 2018; 61:700-710. [PMID: 29332196 PMCID: PMC6448966 DOI: 10.1007/s00125-017-4533-7] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/05/2017] [Accepted: 11/20/2017] [Indexed: 02/08/2023]
Abstract
AIMS/HYPOTHESIS A new class of treatments termed bioelectronic medicines are now emerging that aim to target individual nerve fibres or specific brain circuits in pathological conditions to repair lost function and reinstate a healthy balance. Carotid sinus nerve (CSN) denervation has been shown to improve glucose homeostasis in insulin-resistant and glucose-intolerant rats; however, these positive effects from surgery appear to diminish over time and are heavily caveated by the severe adverse effects associated with permanent loss of chemosensory function. Herein we characterise the ability of a novel bioelectronic application, classified as kilohertz frequency alternating current (KHFAC) modulation, to suppress neural signals within the CSN of rodents. METHODS Rats were fed either a chow or high-fat/high-sucrose (HFHSu) diet (60% lipid-rich diet plus 35% sucrose drinking water) over 14 weeks. Neural interfaces were bilaterally implanted in the CSNs and attached to an external pulse generator. The rats were then randomised to KHFAC or sham modulation groups. KHFAC modulation variables were defined acutely by respiratory and cardiac responses to hypoxia (10% O2 + 90% N2). Insulin sensitivity was evaluated periodically through an ITT and glucose tolerance by an OGTT. RESULTS KHFAC modulation of the CSN, applied over 9 weeks, restored insulin sensitivity (constant of the insulin tolerance test [KITT] HFHSu sham, 2.56 ± 0.41% glucose/min; KITT HFHSu KHFAC, 5.01 ± 0.52% glucose/min) and glucose tolerance (AUC HFHSu sham, 1278 ± 20.36 mmol/l × min; AUC HFHSu KHFAC, 1054.15 ± 62.64 mmol/l × min) in rat models of type 2 diabetes. Upon cessation of KHFAC, insulin resistance and glucose intolerance returned to normal values within 5 weeks. CONCLUSIONS/INTERPRETATION KHFAC modulation of the CSN improves metabolic control in rat models of type 2 diabetes. These positive outcomes have significant translational potential as a novel therapeutic modality for the purpose of treating metabolic diseases in humans.
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Affiliation(s)
- Joana F Sacramento
- CEDOC, NOVA Medical School, Faculdade de Ciências, Universidade NOVA de Lisboa, Rua Camara Pestana, no. 6, 6A, edificio II, piso 3, 1150-082, Lisboa, Portugal
| | | | - Bernardete F Melo
- CEDOC, NOVA Medical School, Faculdade de Ciências, Universidade NOVA de Lisboa, Rua Camara Pestana, no. 6, 6A, edificio II, piso 3, 1150-082, Lisboa, Portugal
| | | | | | - Maria P Guarino
- CEDOC, NOVA Medical School, Faculdade de Ciências, Universidade NOVA de Lisboa, Rua Camara Pestana, no. 6, 6A, edificio II, piso 3, 1150-082, Lisboa, Portugal
- Escola Superior de Saúde de Leiria-Instituto Politécnico de Leiria, Leiria, Portugal
| | | | - Jesus Prieto-Lloret
- CEDOC, NOVA Medical School, Faculdade de Ciências, Universidade NOVA de Lisboa, Rua Camara Pestana, no. 6, 6A, edificio II, piso 3, 1150-082, Lisboa, Portugal
| | | | | | | | | | | | - Silvia V Conde
- CEDOC, NOVA Medical School, Faculdade de Ciências, Universidade NOVA de Lisboa, Rua Camara Pestana, no. 6, 6A, edificio II, piso 3, 1150-082, Lisboa, Portugal.
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21
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Pijacka W, Katayama PL, Salgado HC, Lincevicius GS, Campos RR, McBryde FD, Paton JFR. Variable role of carotid bodies in cardiovascular responses to exercise, hypoxia and hypercapnia in spontaneously hypertensive rats. J Physiol 2018; 596:3201-3216. [PMID: 29313987 DOI: 10.1113/jp275487] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2017] [Accepted: 12/29/2017] [Indexed: 12/20/2022] Open
Abstract
KEY POINTS Carotid bodies play a critical role in maintaining arterial pressure during hypoxia and this has important implications when considering resection therapy of the carotid body in disease states such as hypertension. Curbing hypertension in patients whether resting or under stress remains a major global health challenge. We demonstrated previously the benefits of removing carotid body afferent input into the brain for both alleviating sympathetic overdrive and reducing blood pressure in neurogenic hypertension. We describe a new approach in rats for selective ablation of the carotid bodies that spares the functional integrity of the carotid sinus baroreceptors, and demonstrate the importance of the carotid bodies in the haemodynamic response to forced exercise, hypoxia and hypercapnia in conditions of hypertension. Selective ablation reduced blood pressure in hypertensive rats and re-set baroreceptor reflex function accordingly; the increases in blood pressure seen during exercise, hypoxia and hypercapnia were unaffected, abolished and augmented, respectively, after selective carotid body removal. The data suggest that carotid body ablation may trigger potential cardiovascular risks particularly during hypoxia and hypercapnia and that suppression rather than obliteration of their activity may be a more effective and safer route to pursue. ABSTRACT The carotid body has recently emerged as a promising therapeutic target for treating cardiovascular disease, but the potential impact of carotid body removal on the dynamic cardiovascular responses to acute stressors such as exercise, hypoxia and hypercapnia in hypertension is an important safety consideration that has not been studied. We first validated a novel surgical approach to selectively resect the carotid bodies bilaterally (CBR) sparing the carotid sinus baroreflex. Second, we evaluated the impact of CBR on the cardiovascular responses to exercise, hypoxia and hypercapnia in conscious, chronically instrumented spontaneously hypertensive (SH) rats. The results confirm that our CBR technique successfully and selectively abolished the chemoreflex, whilst preserving carotid baroreflex function. CBR produced a sustained fall in arterial pressure in the SH rat of ∼20 mmHg that persisted across both dark and light phases (P < 0.001), with baroreflex function curves resetting around lower arterial pressure levels. The cardiovascular and respiratory responses to moderate forced exercise were similar between CBR and Sham rats. In contrast, CBR abolished the pressor response to hypoxia seen in Sham animals, although the increases in heart rate and respiration were similar between Sham and CBR groups. Both the pressor and the respiratory responses to 7% hypercapnia were augmented after CBR (P < 0.05) compared to sham. Our finding that the carotid bodies play a critical role in maintaining arterial pressure during hypoxia has important implications when considering resection therapy of the carotid body in disease states such as hypertension as well as heart failure with sleep apnoea.
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Affiliation(s)
- Wioletta Pijacka
- Bristol CardioNomics Group, School of Physiology, Pharmacology and Neuroscience, Medical Sciences Building, University of Bristol, Bristol, BS8 1TD, UK
| | - Pedro L Katayama
- Bristol CardioNomics Group, School of Physiology, Pharmacology and Neuroscience, Medical Sciences Building, University of Bristol, Bristol, BS8 1TD, UK.,Department of Physiology, Ribeirão Preto Medical School, University of São Paulo, Ribeirão Preto, Brazil
| | - Helio C Salgado
- Department of Physiology, Ribeirão Preto Medical School, University of São Paulo, Ribeirão Preto, Brazil
| | - Gisele S Lincevicius
- Bristol CardioNomics Group, School of Physiology, Pharmacology and Neuroscience, Medical Sciences Building, University of Bristol, Bristol, BS8 1TD, UK.,Cardiovascular Division - Department of Physiology, Escola Paulista de Medicina, Universidade Federal de Sao Paulo, Brazil
| | - Ruy R Campos
- Cardiovascular Division - Department of Physiology, Escola Paulista de Medicina, Universidade Federal de Sao Paulo, Brazil
| | - Fiona D McBryde
- Cardiovascular Autonomic Research Cluster, Department of Physiology, Faculty of Medical and Health Sciences, University of Auckland, Private Bag 92019, Auckland, 1142, New Zealand
| | - Julian F R Paton
- Bristol CardioNomics Group, School of Physiology, Pharmacology and Neuroscience, Medical Sciences Building, University of Bristol, Bristol, BS8 1TD, UK.,Cardiovascular Autonomic Research Cluster, Department of Physiology, Faculty of Medical and Health Sciences, University of Auckland, Private Bag 92019, Auckland, 1142, New Zealand
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22
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Naeije R, Faoro V. The great breathlessness of cardiopulmonary diseases. Eur Respir J 2018; 51:51/2/1702517. [PMID: 29437948 DOI: 10.1183/13993003.02517-2017] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2017] [Accepted: 12/05/2017] [Indexed: 11/05/2022]
Affiliation(s)
- Robert Naeije
- Dept of Cardiology, Erasme University Hospital, Brussels, Belgium .,Dept of Cardiorespiratory Exercise Physiology, Faculty of Motor Sciences, Université Libre de Bruxelles, Brussels, Belgium
| | - Vitalie Faoro
- Dept of Cardiorespiratory Exercise Physiology, Faculty of Motor Sciences, Université Libre de Bruxelles, Brussels, Belgium
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23
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Conde SV, Sacramento JF, Guarino MP. Carotid body: a metabolic sensor implicated in insulin resistance. Physiol Genomics 2018; 50:208-214. [PMID: 29373079 DOI: 10.1152/physiolgenomics.00121.2017] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
Abstract
The carotid body is now looked at as a multipurpose sensor for blood gases, blood pH, and several hormones. The matter of glucose sensing by the carotid body has been debated for several years in the literature, and these days there is a consensus that carotid body activity is modified by metabolic factors that contribute to glucose homeostasis. However, the sensing ability for glucose is still being pondered: are the carotid bodies low glucose sensors or, in contrast, are they overresponsive in high-glucose conditions? Herein, we debate the glucose and insulin sensing capabilities of the carotid body as key early events in the overactivation of the carotid body, which is increasingly recognized as an important feature of metabolic diseases. Additionally, we dedicate a final section to discuss new outside-the-box therapies designed to decrease carotid body activity that may be used for treating metabolic diseases.
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Affiliation(s)
- Silvia V Conde
- CEDOC, NOVA Medical School, Faculdade de Ciências, Universidade NOVA de Lisboa , Lisbon , Portugal
| | - Joana F Sacramento
- CEDOC, NOVA Medical School, Faculdade de Ciências, Universidade NOVA de Lisboa , Lisbon , Portugal
| | - Maria P Guarino
- CEDOC, NOVA Medical School, Faculdade de Ciências, Universidade NOVA de Lisboa , Lisbon , Portugal.,School of Health Sciences, Polytechnic Institute of Leiria , Leiria , Portugal
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24
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Conde SV, Monteiro EC, Sacramento JF. Purines and Carotid Body: New Roles in Pathological Conditions. Front Pharmacol 2017; 8:913. [PMID: 29311923 PMCID: PMC5733106 DOI: 10.3389/fphar.2017.00913] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2017] [Accepted: 11/29/2017] [Indexed: 01/28/2023] Open
Abstract
It is known that adenosine and adenosine-5′-triphosphate (ATP) are excitatory mediators involved in carotid body (CB) hypoxic signaling. The CBs are peripheral chemoreceptors classically defined by O2, CO2, and pH sensors. When hypoxia activates the CB, it induces the release of neurotransmitters from chemoreceptor cells leading to an increase in the action potentials frequency at the carotid sinus nerve (CSN). This increase in the firing frequency of the CSN is integrated in the brainstem to induce cardiorespiratory compensatory responses. In the last decade several pathologies, as, hypertension, diabetes, obstructive sleep apnea and heart failure have been associated with CB overactivation. In the first section of the present manuscript we review in a concise manner fundamental aspects of purine metabolism. The second section is devoted to the role of purines on the hypoxic response of the CB, providing the state-of-the art for the presence of adenosine and ATP receptors in the CB; for the role of purines at presynaptic level in CB chemoreceptor cells, as well as, its metabolism and regulation; at postsynaptic level in the CSN activity; and on the ventilatory responses to hypoxia. Recently, we have showed that adenosine is involved in CB hypersensitization during chronic intermittent hypoxia (CIH), which mimics obstructive sleep apnea, since caffeine, a non-selective adenosine receptor antagonist that inhibits A2A and A2B adenosine receptors, decreased CSN chemosensory activity in animals subjected to CIH. Apart from this involvement of adenosine in CB sensitization in sleep apnea, it was recently found that P2X3 ATP receptor in the CB contributes to increased chemoreflex hypersensitivity and hypertension in spontaneously hypertension rats. Therefore the last section of this manuscript is devoted to review the recent findings on the role of purines in CB-mediated pathologies as hypertension, diabetes and sleep apnea emphasizing the potential clinical importance of modulating purines levels and action to treat pathologies associated with CB dysfunction.
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Affiliation(s)
- Silvia V Conde
- Centro de Estudos de Doenças Crónicas, NOVA Medical School - Faculdade de Ciências Médicas, Universidade NOVA de Lisboa, Lisboa, Portugal
| | - Emilia C Monteiro
- Centro de Estudos de Doenças Crónicas, NOVA Medical School - Faculdade de Ciências Médicas, Universidade NOVA de Lisboa, Lisboa, Portugal
| | - Joana F Sacramento
- Centro de Estudos de Doenças Crónicas, NOVA Medical School - Faculdade de Ciências Médicas, Universidade NOVA de Lisboa, Lisboa, Portugal
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25
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Sheikhbahaei S, Gourine AV, Smith JC. Respiratory rhythm irregularity after carotid body denervation in rats. Respir Physiol Neurobiol 2017; 246:92-97. [PMID: 28782663 PMCID: PMC5637156 DOI: 10.1016/j.resp.2017.08.001] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2017] [Revised: 07/09/2017] [Accepted: 08/01/2017] [Indexed: 12/13/2022]
Abstract
Respiratory activity is controlled by inputs from the peripheral and central chemoreceptors. Since overactivity of the carotid bodies, the main peripheral chemoreceptors, is linked to the pathophysiology of disparate metabolic and cardiovascular diseases, carotid body denervation (CBD) has been proposed as a potential treatment. However, long-term effects of CBD on the respiratory rhythm and regularity of breathing remain unknown. Here, we show that five weeks after bilateral CBD in rats, the respiratory rhythm was slower and less regular. Ten weeks after bilateral CBD, the respiratory frequency was not different from the sham-operated group, but the regularity of the respiratory rhythm was still reduced. Increased frequency of randomly occurring apneas is likely to be responsible for the irregular breathing pattern after CBD. These results should be taken into consideration since any treatment that reduces the stability of the respiratory rhythm might exacerbate the cardio-respiratory instability and worsen the cardiovascular outcomes.
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Affiliation(s)
- Shahriar Sheikhbahaei
- Cellular and Systems Neurobiology Section, National Institute of Neurological Disorders and Stroke (NINDS), National Institutes of Health (NIH), Bethesda, MD, USA; Centre for Cardiovascular and Metabolic Neuroscience, Department of Neuroscience, Physiology, and Pharmacology, University College London, London WC1E 6BT, UK.
| | - Alexander V Gourine
- Centre for Cardiovascular and Metabolic Neuroscience, Department of Neuroscience, Physiology, and Pharmacology, University College London, London WC1E 6BT, UK
| | - Jeffrey C Smith
- Cellular and Systems Neurobiology Section, National Institute of Neurological Disorders and Stroke (NINDS), National Institutes of Health (NIH), Bethesda, MD, USA
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26
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Iturriaga R. Translating carotid body function into clinical medicine. J Physiol 2017; 596:3067-3077. [PMID: 29114876 DOI: 10.1113/jp275335] [Citation(s) in RCA: 39] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2017] [Accepted: 10/18/2017] [Indexed: 12/12/2022] Open
Abstract
The carotid body (CB) is considered the main O2 chemoreceptor, which contributes to cardiorespiratory homeostasis and ventilatory acclimatization. In clinical medicine, the most common pathologies associated with the CB are tumours. However, a growing body of evidence supports the novel idea that an enhanced CB chemosensory discharge contributes to the autonomic dysfunction and pathological consequences in obstructive sleep apnoea (OSA), hypertension, systolic heart failure (HF) and cardiometabolic diseases. Heightened CB chemosensory reactivity elicited by oxidative stress has been involved in sympathetic hyperactivity, cardiorespiratory instability, hypertension and insulin resistance. CB ablation, which reduces sympathetic hyperactivity, decreases hypertension in animal models of OSA and hypertension, eliminates breathing instability and improves animal survival in HF, and restores insulin tolerance in cardiometabolic models. Thus, data obtained from preclinical studies highlight the importance of the CB in the progression of sympathetic-related diseases, supporting the idea that appeasing the enhanced CB chemosensory drive may be useful in improving cardiovascular, respiratory and endocrine alterations. Accordingly, CB ablation has been proposed and used as a treatment for moderating resistant hypertension and HF-induced sympathetic hyperactivity in humans. First-in-human studies have shown that CB ablation reduces sympathetic overactivity, transiently reduces severe hypertension and improves quality of life in HF patients. Thus, CB ablation would be a useful therapy to reverse sympathetic overactivation in HF and severe hypertension, but caution is required before it is widely used due to the crucial physiological function played by the CB. Further studies in preclinical models are required to assess side-effects of CB ablation.
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Affiliation(s)
- Rodrigo Iturriaga
- Laboratorio de Neurobiología, Facultad de Ciencias Biológicas, Pontificia Universidad Católica de Chile, Santiago, Chile
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27
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van Bilsen M, Patel HC, Bauersachs J, Böhm M, Borggrefe M, Brutsaert D, Coats AJS, de Boer RA, de Keulenaer GW, Filippatos GS, Floras J, Grassi G, Jankowska EA, Kornet L, Lunde IG, Maack C, Mahfoud F, Pollesello P, Ponikowski P, Ruschitzka F, Sabbah HN, Schultz HD, Seferovic P, Slart RHJA, Taggart P, Tocchetti CG, Van Laake LW, Zannad F, Heymans S, Lyon AR. The autonomic nervous system as a therapeutic target in heart failure: a scientific position statement from the Translational Research Committee of the Heart Failure Association of the European Society of Cardiology. Eur J Heart Fail 2017; 19:1361-1378. [PMID: 28949064 DOI: 10.1002/ejhf.921] [Citation(s) in RCA: 103] [Impact Index Per Article: 14.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/09/2017] [Revised: 04/23/2017] [Accepted: 05/24/2017] [Indexed: 12/20/2022] Open
Abstract
Despite improvements in medical therapy and device-based treatment, heart failure (HF) continues to impose enormous burdens on patients and health care systems worldwide. Alterations in autonomic nervous system (ANS) activity contribute to cardiac disease progression, and the recent development of invasive techniques and electrical stimulation devices has opened new avenues for specific targeting of the sympathetic and parasympathetic branches of the ANS. The Heart Failure Association of the European Society of Cardiology recently organized an expert workshop which brought together clinicians, trialists and basic scientists to discuss the ANS as a therapeutic target in HF. The questions addressed were: (i) What are the abnormalities of ANS in HF patients? (ii) What methods are available to measure autonomic dysfunction? (iii) What therapeutic interventions are available to target the ANS in patients with HF, and what are their specific strengths and weaknesses? (iv) What have we learned from previous ANS trials? (v) How should we proceed in the future?
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Affiliation(s)
- Marc van Bilsen
- Department of Cardiology, Cardiovascular Research Institute Maastricht (CARIM), Maastricht University Medical Hospital, Maastricht, the Netherlands
| | - Hitesh C Patel
- National Institute for Health Research (NIHR) Cardiovascular Biomedical Research Unit, Royal Brompton Hospital, London, UK.,National Heart and Lung Institute, Imperial College London, London, UK.,Baker Heart and Diabetes Institute, Melbourne, Vic, Australia
| | - Johann Bauersachs
- Department of Cardiology and Angiology, Medical School Hannover, Hannover, Germany
| | - Michael Böhm
- Clinic for Internal Medicine III, Cardiology, Angiology and Intensive Internal Medicine, Homburg, Germany
| | - Martin Borggrefe
- First Department of Medicine, Cardiology Division, University Medical Centre Mannheim, Mannheim, Germany.,German Centre for Cardiovascular Research, Mannheim, Germany
| | - Dirk Brutsaert
- Department of Cardiology, Antwerp University, Antwerp, Belgium
| | - Andrew J S Coats
- Department of Medicine, Monash University, Melbourne, Vic, Australia.,Department of Medicine, University of Warwick, Coventry, UK
| | - Rudolf A de Boer
- Department of Cardiology, University Medical Centre Groningen, University of Groningen, Groningen, the Netherlands
| | | | - Gerasimos S Filippatos
- Department of Cardiology, School of Medicine, National and Kapodistrian University of Athens, Athens University Hospital Attikon, Athens, Greece
| | - John Floras
- University Health Network and Sinai Health System Division of Cardiology, Peter Munk Cardiac Centre, Toronto General and Lunenfeld-Tanenbaum Research Institutes, University of Toronto, Toronto, ON, Canada
| | - Guido Grassi
- Clinica Medica, Department of Medicine and Surgery, University of Milan-Bicocca, Milan, Italy.,IRCCS Multimedica, Milan, Italy
| | - Ewa A Jankowska
- Department of Heart Diseases, Wroclaw Medical University, Wroclaw, Poland.,Centre for Heart Diseases, Military Hospital, Wroclaw, Poland
| | - Lilian Kornet
- Medtronic, Inc., Bakken Research Centre, Maastricht, the Netherlands
| | - Ida G Lunde
- Institute for Experimental Medical Research, Oslo University Hospital, University of Oslo, Oslo, Norway
| | - Christoph Maack
- Clinic for Internal Medicine III, Cardiology, Angiology and Intensive Internal Medicine, Homburg, Germany
| | - Felix Mahfoud
- Clinic for Internal Medicine III, Cardiology, Angiology and Intensive Internal Medicine, Homburg, Germany
| | | | - Piotr Ponikowski
- Department of Heart Diseases, Wroclaw Medical University, Wroclaw, Poland.,Centre for Heart Diseases, Military Hospital, Wroclaw, Poland
| | - Frank Ruschitzka
- University Heart Centre, University Hospital Zurich, Zurich, Switzerland
| | - Hani N Sabbah
- Department of Medicine, Division of Cardiovascular Medicine, Henry Ford Hospital, Detroit, MI, USA
| | - Harold D Schultz
- Department of Cellular and Integrative Physiology, University of Nebraska College of Medicine, Omaha, NE, USA
| | - Petar Seferovic
- Department of Cardiology, Belgrade University Medical Centre, Belgrade, Serbia
| | - Riemer H J A Slart
- Department of Nuclear Medicine and Molecular Imaging, University of Groningen, University Medical Centre Groningen, Groningen, the Netherlands.,Department of Biomedical Photonic Imaging, Faculty of Science and Technology, University of Twente, Enschede, the Netherlands
| | - Peter Taggart
- Department of Cardiovascular Science, University College London, Barts Heart Centre, London, UK
| | - Carlo G Tocchetti
- Department of Translational Medical Sciences, Federico II University, Naples, Italy
| | - Linda W Van Laake
- Department of Cardiology, Heart and Lungs Division, and Regenerative Medicine Centre, University Medical Centre Utrecht, Utrecht, the Netherlands
| | - Faiez Zannad
- INSERM, Centre for Clinical Investigation 9501, Unit 961, University Hospital Centre, Nancy, France.,Department of Cardiology, Nancy University, University of the Lorraine, Nancy, France
| | - Stephane Heymans
- Netherlands Heart Institute, Utrecht, the Netherlands.,Department of Cardiovascular Sciences, Leuven University, Leuven, Belgium
| | - Alexander R Lyon
- National Institute for Health Research (NIHR) Cardiovascular Biomedical Research Unit, Royal Brompton Hospital, London, UK.,National Heart and Lung Institute, Imperial College London, London, UK
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28
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Visualizing Carotid Bodies With Doppler Ultrasound Versus CT Angiography: Preliminary Study. AJR Am J Roentgenol 2017; 209:1348-1352. [PMID: 28871807 DOI: 10.2214/ajr.17.18079] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
OBJECTIVE The purpose of this article is to evaluate the utility of ultrasound in identifying carotid bodies (CBs) in patients with drug-resistant arterial hypertension. SUBJECTS AND METHODS We enrolled 13 patients with drug-resistant hypertension into a trial for surgical CB excision. CT angiography (CTA) and Doppler ultrasound (DUS) of the cervical arteries were performed before surgery. CBs were identified in a blind manner at both CTA and DUS. CBs were defined at CTA as ovoid avidly enhancing structures at the inferomedial aspect of the carotid bifurcation. At DUS, CBs were defined as ovoid solid structures in the inferomedial aspect of the bifurcation. RESULTS CBs were identified in 12 of 13 patients (23/26 sides) using CTA and in 11 of 13 patients (18/26 sides) using DUS. Identification of CB with DUS and CTA correlated in 17 of 18 cases; in one instance, CB was identified with DUS but not CTA. There was no statistically significant difference in size and volume of CB measured by both methods. CONCLUSION Noncarcinogenic CBs can be visualized using DUS, with good correlation of size and location compared with CTA. The findings show that DUS can be reliably used to further examine the role of CBs in cardiovascular disorders and can be used in conjunction with therapies that target CBs.
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29
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Affiliation(s)
- Marat Fudim
- Division of Cardiology, Department of Internal Medicine, Duke University Hospital, Durham, NC
| | - Adrian F Hernandez
- Division of Cardiology, Department of Internal Medicine, Duke University Hospital, Durham, NC
- Duke Cardiovascular Research Institute, Durham, NC
| | - G Michael Felker
- Division of Cardiology, Department of Internal Medicine, Duke University Hospital, Durham, NC
- Duke Cardiovascular Research Institute, Durham, NC
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30
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Lachowska K, Gruchała M, Narkiewicz K, Hering D. Sympathetic Activation in Chronic Heart Failure: Potential Benefits of Interventional Therapies. Curr Hypertens Rep 2017; 18:51. [PMID: 27193773 DOI: 10.1007/s11906-016-0660-7] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
Heart failure (HF) is a major and growing public health problem. This condition is associated with poor prognosis, a high rate of mortality, frequent hospitalization and increasing costs to health care systems. Pharmacological approaches aimed at reducing morbidity and mortality in HF have primarily focused on inhibition of the renin-angiotensin-aldosterone system (RAAS) and the sympathetic nervous system (SNS), both of which have been associated with disease development, progression and adverse cardiovascular (CV) outcomes. The increasing number of hospitalizations for HF decompensation suggests the failure of available treatment options, indicating the necessity for alternative therapeutic approaches. Alongside pharmacological and cardiac resynchronization therapies in selected patients with arrhythmia, recent advancements in the management of HF have been directed at inhibiting relevant neurogenic pathways underlying disease development and progression. Initial evidence regarding the safety and effectiveness of interventional procedures suggests that HF patients may benefit from novel adjunctive therapies. Here we review the critical role of sympathetic activation in HF and the rationale for therapeutic interventions including device-based and interventional approaches aimed at restoring autonomic neural balance in this condition.
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Affiliation(s)
- Kamila Lachowska
- First Department of Cardiology, Medical University of Gdansk, Gdansk, Poland
| | - Marcin Gruchała
- First Department of Cardiology, Medical University of Gdansk, Gdansk, Poland
| | - Krzysztof Narkiewicz
- Department of Hypertension and Diabetology, Medical University of Gdansk, Gdansk, Poland
| | - Dagmara Hering
- Dobney Hypertension Centre, School of Medicine and Pharmacology-Royal Perth Hospital Unit, The University of Western Australia, Level 3 MRF Building, Rear 50 Murray Street, Perth, WA, 6000, MDBP: M570, Australia.
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31
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Sands SA, Mebrate Y, Edwards BA, Nemati S, Manisty CH, Desai AS, Wellman A, Willson K, Francis DP, Butler JP, Malhotra A. Resonance as the Mechanism of Daytime Periodic Breathing in Patients with Heart Failure. Am J Respir Crit Care Med 2017; 195:237-246. [PMID: 27559818 DOI: 10.1164/rccm.201604-0761oc] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
RATIONALE In patients with chronic heart failure, daytime oscillatory breathing at rest is associated with a high risk of mortality. Experimental evidence, including exaggerated ventilatory responses to CO2 and prolonged circulation time, implicates the ventilatory control system and suggests feedback instability (loop gain > 1) is responsible. However, daytime oscillatory patterns often appear remarkably irregular versus classic instability (Cheyne-Stokes respiration), suggesting our mechanistic understanding is limited. OBJECTIVES We propose that daytime ventilatory oscillations generally result from a chemoreflex resonance, in which spontaneous biological variations in ventilatory drive repeatedly induce temporary and irregular ringing effects. Importantly, the ease with which spontaneous biological variations induce irregular oscillations (resonance "strength") rises profoundly as loop gain rises toward 1. We tested this hypothesis through a comparison of mathematical predictions against actual measurements in patients with heart failure and healthy control subjects. METHODS In 25 patients with chronic heart failure and 25 control subjects, we examined spontaneous oscillations in ventilation and separately quantified loop gain using dynamic inspired CO2 stimulation. MEASUREMENTS AND MAIN RESULTS Resonance was detected in 24 of 25 patients with heart failure and 18 of 25 control subjects. With increased loop gain-consequent to increased chemosensitivity and delay-the strength of spontaneous oscillations increased precipitously as predicted (r = 0.88), yielding larger (r = 0.78) and more regular (interpeak interval SD, r = -0.68) oscillations (P < 0.001 for all, both groups combined). CONCLUSIONS Our study elucidates the mechanism underlying daytime ventilatory oscillations in heart failure and provides a means to measure and interpret these oscillations to reveal the underlying chemoreflex hypersensitivity and reduced stability that foretells mortality in this population.
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Affiliation(s)
- Scott A Sands
- 1 Division of Sleep and Circadian Disorders and.,2 Department of Allergy, Immunology and Respiratory Medicine and Central Clinical School, The Alfred and Monash University, Melbourne, Victoria, Australia
| | - Yoseph Mebrate
- 3 International Center for Circulatory Health, National Heart and Lung Institute, Imperial College London, London, United Kingdom.,4 Department of Clinical Engineering, Royal Brompton Hospital, London, United Kingdom
| | - Bradley A Edwards
- 1 Division of Sleep and Circadian Disorders and.,5 Sleep and Circadian Medicine Laboratory, Department of Physiology, and.,6 School of Psychological Sciences and Monash Institute of Cognitive and Clinical Neurosciences, Monash University, Melbourne, Victoria, Australia
| | | | - Charlotte H Manisty
- 7 Institute of Cardiovascular Sciences, University College London, London, United Kingdom; and
| | - Akshay S Desai
- 8 Division of Cardiovascular Medicine, Brigham and Women's Hospital and Harvard Medical School, Boston, Massachusetts
| | | | - Keith Willson
- 3 International Center for Circulatory Health, National Heart and Lung Institute, Imperial College London, London, United Kingdom
| | - Darrel P Francis
- 3 International Center for Circulatory Health, National Heart and Lung Institute, Imperial College London, London, United Kingdom
| | | | - Atul Malhotra
- 1 Division of Sleep and Circadian Disorders and.,9 Division of Pulmonary and Critical Care Medicine, University of California San Diego, La Jolla, California
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32
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Fudim M, Piccini JP. Treating cardiac dysrhythmias by targeting the neck: Off target or on the right track? J Cardiovasc Electrophysiol 2017; 28:909-911. [DOI: 10.1111/jce.13274] [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] [Received: 05/31/2017] [Accepted: 06/05/2017] [Indexed: 11/30/2022]
Affiliation(s)
- Marat Fudim
- Cardiac Electrophsiology Section, Division of Cardiology; Duke University Medical Center; Durham NC USA
| | - Jonathan P. Piccini
- Cardiac Electrophsiology Section, Division of Cardiology; Duke University Medical Center; Durham NC USA
- Duke Clinical Research Institute; Durham NC USA
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33
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McBryde FD, Hart EC, Ramchandra R, Paton JF. Evaluating the carotid bodies and renal nerves as therapeutic targets for hypertension. Auton Neurosci 2017; 204:126-130. [DOI: 10.1016/j.autneu.2016.08.002] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2016] [Revised: 07/28/2016] [Accepted: 08/01/2016] [Indexed: 11/30/2022]
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34
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Larson KF, Limberg JK, Baker SE, Joyner MJ, Curry TB. Intact blood pressure, but not sympathetic, responsiveness to sympathoexcitatory stimuli in a patient with unilateral carotid body resection. Physiol Rep 2017; 5:5/7/e13212. [PMID: 28364029 PMCID: PMC5392508 DOI: 10.14814/phy2.13212] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2016] [Revised: 02/22/2017] [Accepted: 02/23/2017] [Indexed: 11/24/2022] Open
Abstract
Despite rapidly growing interest in the therapeutic resection of the carotid body (CB) chemoreceptors, few physiologic studies exist on the consequences of unilateral CB resection. We present a case of an otherwise healthy postmenopausal female who underwent unilateral CB resection for a paraganglioma. Approximately 4 years postoperatively, she underwent analysis of her sympathetic and hemodynamic responses to hypoxia, lower body negative pressure, cold pressor test (CPT), and ischemic hand grip exercise and postexercise ischemia (IHE/PEI). Hypoxic ventilatory response and baroreflex sensitivity were relatively normal. Hemodynamic responses to IHE/PEI and CPT showed characteristic increases in cardiac output (from 3.9 L/min to 5.2 L/min [IHE/PEI] and 4.9 L/min [CPT]) and blood pressure (from 126/72 mmHg to 161/87 mmHg [IHE/PEI] and 171/93 mmHg [CPT]). However, muscle sympathetic nerve activity (microneurography of the peroneal nerve) decreased from baseline during IHE/PEI and CPT (burst incidence nadir of 45% and 40% of baseline, respectively) and there was no observable change in total peripheral resistance (from 24 mmHg*min/L to 22 mmHg*min/L [IHE/PEI] and 25 mmHg*min/L [CPT]). These findings illustrate intact blood pressure responsiveness despite attenuated sympathoexcitation, possibly due to an increase in cardiac output and/or adaptive inhibitory effect of the baroreflex on peripheral sympathetic activity.
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Affiliation(s)
| | | | - Sarah E Baker
- Department of Anesthesiology, Mayo Clinic, Rochester, Minnesota
| | | | - Timothy B Curry
- Department of Anesthesiology, Mayo Clinic, Rochester, Minnesota
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35
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Conde SV, Ribeiro MJ, Melo BF, Guarino MP, Sacramento JF. Insulin resistance: a new consequence of altered carotid body chemoreflex? J Physiol 2017; 595:31-41. [PMID: 27027507 PMCID: PMC5199745 DOI: 10.1113/jp271684] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2015] [Accepted: 03/11/2016] [Indexed: 01/22/2023] Open
Abstract
Metabolic diseases affect millions of individuals across the world and represent a group of chronic diseases of very high prevalence and relatively low therapeutic success, making them suitable candidates for pathophysiological studies. The sympathetic nervous system (SNS) contributes to the regulation of energy balance and energy expenditure both in physiological and pathological states. For instance, drugs that stimulate sympathetic activity decrease food intake, increase resting metabolic rate and increase the thermogenic response to food, while pharmacological blockade of the SNS has opposite effects. Likewise, dysmetabolic features such as insulin resistance, dyslipidaemia and obesity are characterized by a basal overactivation of the SNS. Recently, a new line of research linking the SNS to metabolic diseases has emerged with the report that the carotid bodies (CBs) are involved in the development of insulin resistance. The CBs are arterial chemoreceptors that classically sense changes in arterial blood O2 , CO2 and pH levels and whose activity is known to be increased in rodent models of insulin resistance. We have shown that selective bilateral resection of the nerve of the CB, the carotid sinus nerve (CSN), totally prevents diet-induced insulin resistance, hyperglycaemia, dyslipidaemia, hypertension and sympathoadrenal overactivity. These results imply that the beneficial effects of CSN resection on insulin action and glucoregulation are modulated by target-related efferent sympathetic nerves through a reflex that is initiated in the CBs. It also highlights modulation of CB activity as a putative future therapeutic intervention for metabolic diseases.
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Affiliation(s)
- Silvia V. Conde
- CEDOC, Centro Estudos Doenças Crónicas, NOVA Medical School, Faculdade de Ciências MédicasUniversidade Nova de LisboaLisboaPortugal
| | - Maria J. Ribeiro
- CEDOC, Centro Estudos Doenças Crónicas, NOVA Medical School, Faculdade de Ciências MédicasUniversidade Nova de LisboaLisboaPortugal
| | - Bernardete F. Melo
- CEDOC, Centro Estudos Doenças Crónicas, NOVA Medical School, Faculdade de Ciências MédicasUniversidade Nova de LisboaLisboaPortugal
| | - Maria P. Guarino
- CEDOC, Centro Estudos Doenças Crónicas, NOVA Medical School, Faculdade de Ciências MédicasUniversidade Nova de LisboaLisboaPortugal
- UIS‐Unidade de Investigação em Saúde – Escola Superior de Saúde de Leiria – Instituto Politécnico de LeiriaLeiriaPortugal
| | - Joana F. Sacramento
- CEDOC, Centro Estudos Doenças Crónicas, NOVA Medical School, Faculdade de Ciências MédicasUniversidade Nova de LisboaLisboaPortugal
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36
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McBryde FD, Malpas SC, Paton JFR. Intracranial mechanisms for preserving brain blood flow in health and disease. Acta Physiol (Oxf) 2017; 219:274-287. [PMID: 27172364 DOI: 10.1111/apha.12706] [Citation(s) in RCA: 55] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2015] [Revised: 02/03/2016] [Accepted: 05/06/2016] [Indexed: 12/19/2022]
Abstract
The brain is an exceptionally energetically demanding organ with little metabolic reserve, and multiple systems operate to protect and preserve the brain blood supply. But how does the brain sense its own perfusion? In this review, we discuss how the brain may harness the cardiovascular system to counter threats to cerebral perfusion sensed via intracranial pressure (ICP), cerebral oxygenation and ischaemia. Since the work of Cushing over 100 years ago, the existence of brain baroreceptors capable of eliciting increases in sympathetic outflow and blood pressure has been hypothesized. In the clinic, this response has generally been thought to occur only in extremis, to perfuse the severely ischaemic brain as cerebral autoregulation fails. We review evidence that pressor responses may also occur with smaller, physiologically relevant increases in ICP. The incoming brain oxygen supply is closely monitored by the carotid chemoreceptors; however, hypoxia and other markers of ischaemia are also sensed intrinsically by astrocytes or other support cells within brain tissue itself and elicit reactive hyperaemia. Recent studies suggest that astrocytic oxygen signalling within the brainstem may directly affect sympathetic nerve activity and blood pressure. We speculate that local cerebral oxygen tension is a major determinant of the mean level of arterial pressure and discuss recent evidence that this may be the case. We conclude that intrinsic intra- and extra-cranial mechanisms sense and integrate information about hypoxia/ischaemia and ICP and play a major role in determining the long-term level of sympathetic outflow and arterial pressure, to optimize cerebral perfusion.
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Affiliation(s)
- F. D. McBryde
- Department of Physiology; Faculty of Medical and Health Sciences; University of Auckland; Auckland New Zealand
- School of Physiology, Pharmacology & Neuroscience; Biomedical Sciences; University of Bristol; Bristol UK
| | - S. C. Malpas
- Department of Physiology; Faculty of Medical and Health Sciences; University of Auckland; Auckland New Zealand
| | - J. F. R. Paton
- Department of Physiology; Faculty of Medical and Health Sciences; University of Auckland; Auckland New Zealand
- School of Physiology, Pharmacology & Neuroscience; Biomedical Sciences; University of Bristol; Bristol UK
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Siński M, Lewandowski J, Dobosiewicz A, Przybylski J, Abramczyk P, Gaciong Z. The effect of hyperoxia on central blood pressure in healthy subjects. Arch Med Sci 2016; 12:992-999. [PMID: 27695489 PMCID: PMC5016570 DOI: 10.5114/aoms.2015.49038] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/08/2014] [Accepted: 01/30/2015] [Indexed: 01/04/2023] Open
Abstract
INTRODUCTION Hyperoxia increases total peripheral resistance by acting locally but also inhibits the activity of carotid body chemoreceptors. We studied the effect of hyperoxia on central pressure in normotensive subjects. MATERIAL AND METHODS Medical air followed by 100% oxygen was provided to 19 subjects (12/7 female/male, age 28.2 ±1.1 years) for 15 min through a non-rebreather mask. Central blood pressure was then measured using applanation tonometry. RESULTS After the first 2 min of hyperoxia, heart rate decreased significantly (65 ±2.6 beats/min vs. 61 ±2.1 beats/min, p = 0.0002). Peripheral and central blood pressure remained unchanged, while hemoglobin oxygen saturation and subendocardial viability ratio index increased (97 ±0.4% vs. 99 ±0.2%, p = 0.03; 168 ±8.4% vs. 180 ±8.2%, p = 0.009). After 15 min of 100% oxygen ventilation, heart rate and peripheral and central blood pressures remained unchanged from the first 2 min. The augmentation index, augmentation pressure and ejection duration increased as compared to baseline values and those obtained at 2 min (-5.1 ±2.9% vs. -1.2 ±2.6%, p = 0.005 and -4.6 ±2.7% vs. -1.2 ±2.6%, p = 0.0015; -1.3 ±0.7 mm Hg vs. -0.2 ±1.2 mm Hg, p = 0.003 and -1.1 ±0.7 mm Hg vs. -0.2 ±1.2 mm Hg, p = 0.012; 323 ±3.6 ms vs. 330 ±3.5 ms, p = 0.0002 and 326 ±3.5 ms vs. 330 ±3.5 ms, p = 0.021, respectively). CONCLUSIONS The present study shows that hyperoxia does not affect central blood pressure in young healthy subjects and may improve myocardial blood supply estimated indirectly from applanation tonometry.
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Affiliation(s)
- Maciej Siński
- Department of Internal Medicine, Hypertension and Vascular Diseases, Medical University of Warsaw, Warsaw, Poland
| | - Jacek Lewandowski
- Department of Internal Medicine, Hypertension and Vascular Diseases, Medical University of Warsaw, Warsaw, Poland
| | - Anna Dobosiewicz
- Department of Pulmonary Circulation and Thromboembolic Diseases, Center of Postgraduate Medical Education, Otwock, Poland
| | - Jacek Przybylski
- Department of Biophysics and Physiology, Medical University of Warsaw, Warsaw, Poland
| | - Piotr Abramczyk
- Department of Internal Medicine, Hypertension and Vascular Diseases, Medical University of Warsaw, Warsaw, Poland
| | - Zbigniew Gaciong
- Department of Internal Medicine, Hypertension and Vascular Diseases, Medical University of Warsaw, Warsaw, Poland
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38
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Pijacka W, McBryde FD, Marvar PJ, Lincevicius GS, Abdala APL, Woodward L, Li D, Paterson DJ, Paton JFR. Carotid sinus denervation ameliorates renovascular hypertension in adult Wistar rats. J Physiol 2016; 594:6255-6266. [PMID: 27510951 DOI: 10.1113/jp272708] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2016] [Accepted: 08/03/2016] [Indexed: 01/24/2023] Open
Abstract
KEY POINTS Peripheral chemoreflex sensitization is a feature of renovascular hypertension. Carotid sinus nerve denervation (CSD) has recently been shown to relieve hypertension and reduce sympathetic activity in other rat models of hypertension. We show that CSD in renovascular hypertension halts further increases in blood pressure. Possible mechanisms include improvements in baroreceptor reflex sensitivity and renal function, restoration of cardiac calcium signalling towards control levels, and reduced neural inflammation. Our data suggest that the peripheral chemoreflex may be a viable therapeutic target for renovascular hypertension. ABSTRACT The peripheral chemoreflex is known to be hyper-responsive in both spontaneously hypertensive (SHR) and Goldblatt hypertensive (two kidney one clip; 2K1C) rats. We have previously shown that carotid sinus nerve denervation (CSD) reduces arterial blood pressure (ABP) in SHR. In the present study, we show that CSD ameliorates 2K1C hypertension and reveal the potential underlying mechanisms. Adult Wistar rats were instrumented to record ABP via telemetry, and then underwent CSD (n = 9) or sham CSD (n = 9) 5 weeks after renal artery clipping, in comparison with normal Wistar rats (n = 5). After 21 days, renal function was assessed, and tissue was collected to assess sympathetic postganglionic intracellular calcium transients ([Ca2+ ]i ) and immune cell infiltrates. Hypertensive 2K1C rats showed a profound elevation in ABP (Wistar: 98 ± 4 mmHg vs. 2K1C: 147 ± 8 mmHg; P < 0.001), coupled with impairments in renal function and baroreflex sensitivity, increased neuroinflammatory markers and enhanced [Ca2+ ]I in stellate neurons (P < 0.05). CSD reduced ABP in 2K1C+CSD rats and prevented the further progressive increase in ABP seen in 2K1C+sham CSD rats, with a between-group difference of 14 ± 2 mmHg by week 3 (P < 0.01), which was accompanied by improvements in both baroreflex control and spectral indicators of cardiac sympatho-vagal balance. Furthermore, CSD improved protein and albuminuria, decreased [Ca2+ ]i evoked responses from stellate neurons, and also reduced indicators of brainstem inflammation. In summary, CSD in 2K1C rats reduces the hypertensive burden and improves renal function. This may be mediated by improvements in autonomic balance, functional remodelling of post-ganglionic neurons and reduced inflammation. Our results suggest that the peripheral chemoreflex may be considered as a potential therapeutic target for controlling renovascular hypertension.
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Affiliation(s)
- Wioletta Pijacka
- School of Physiology, Pharmacology & Neuroscience, Biomedical Sciences, University of Bristol, Bristol, UK
| | - Fiona D McBryde
- School of Physiology, Pharmacology & Neuroscience, Biomedical Sciences, University of Bristol, Bristol, UK.,Department of Physiology, Faculty of Medical and Health Sciences, University of Auckland, Auckland, New Zealand
| | - Paul J Marvar
- Department of Pharmacology and Physiology, The George Washington University School of Medical and Health Sciences, Washington, DC, USA
| | - Gisele S Lincevicius
- Cardiovascular Division - Department of Physiology, Escola Paulista de Medicina, Universidade Federal de, Sao Paulo, Brazil
| | - Ana P L Abdala
- School of Physiology, Pharmacology & Neuroscience, Biomedical Sciences, University of Bristol, Bristol, UK
| | - Lavinia Woodward
- Burdon Sanderson Cardiac Science Centre, Department of Physiology, Anatomy and Genetics, University of Oxford, UK
| | - Dan Li
- Burdon Sanderson Cardiac Science Centre, Department of Physiology, Anatomy and Genetics, University of Oxford, UK
| | - David J Paterson
- Burdon Sanderson Cardiac Science Centre, Department of Physiology, Anatomy and Genetics, University of Oxford, UK
| | - Julian F R Paton
- School of Physiology, Pharmacology & Neuroscience, Biomedical Sciences, University of Bristol, Bristol, UK.
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39
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Niewinski P, Janczak D, Rucinski A, Tubek S, Engelman ZJ, Piesiak P, Jazwiec P, Banasiak W, Fudim M, Sobotka PA, Javaheri S, Hart EC, Paton JF, Ponikowski P. Carotid body resection for sympathetic modulation in systolic heart failure: results from first-in-man study. Eur J Heart Fail 2016; 19:391-400. [DOI: 10.1002/ejhf.641] [Citation(s) in RCA: 80] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/02/2016] [Revised: 07/10/2016] [Accepted: 07/25/2016] [Indexed: 12/30/2022] Open
Affiliation(s)
- Piotr Niewinski
- Department of Cardiology, Centre for Heart Disease; 4th Military Hospital; Wroclaw Poland
| | - Dariusz Janczak
- Department of Vascular Surgery; 4th Military Hospital; Wroclaw Poland
| | - Artur Rucinski
- Department of Vascular Surgery; 4th Military Hospital; Wroclaw Poland
| | - Stanislaw Tubek
- Department of Cardiology, Centre for Heart Disease; 4th Military Hospital; Wroclaw Poland
- Department of Heart Diseases, Faculty of Health Sciences; Wroclaw Medical University; Wroclaw Poland
| | | | - Pawel Piesiak
- Department of Pulmonology and Lung Cancer; Medical University; Wroclaw Poland
| | - Przemyslaw Jazwiec
- Department of Radiology and Diagnostics Imaging; 4th Military Hospital; Wroclaw Poland
| | - Waldemar Banasiak
- Department of Cardiology, Centre for Heart Disease; 4th Military Hospital; Wroclaw Poland
| | - Marat Fudim
- Department of Cardiology; Duke University School of Medicine; Durham NC USA
| | - Paul A. Sobotka
- Cibiem Inc.; Los Altos CA USA
- The Ohio State University; Columbus OH USA
| | - Shahrokh Javaheri
- Bethesda North Hospital; Cincinnati OH USA
- University of Cincinnati; Cincinnati OH USA
| | - Emma C.J. Hart
- School of Physiology and Pharmacology, Clinical Research & Imaging Centre; University of Bristol; Bristol UK
| | - Julian F.R. Paton
- School of Physiology and Pharmacology, Clinical Research & Imaging Centre; University of Bristol; Bristol UK
| | - Piotr Ponikowski
- Department of Cardiology, Centre for Heart Disease; 4th Military Hospital; Wroclaw Poland
- Department of Heart Diseases, Faculty of Health Sciences; Wroclaw Medical University; Wroclaw Poland
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Abstract
Cardiac control is mediated via a series of reflex control networks involving somata in the (i) intrinsic cardiac ganglia (heart), (ii) intrathoracic extracardiac ganglia (stellate, middle cervical), (iii) superior cervical ganglia, (iv) spinal cord, (v) brainstem, and (vi) higher centers. Each of these processing centers contains afferent, efferent, and local circuit neurons, which interact locally and in an interdependent fashion with the other levels to coordinate regional cardiac electrical and mechanical indices on a beat-to-beat basis. This control system is optimized to respond to normal physiological stressors (standing, exercise, and temperature); however, it can be catastrophically disrupted by pathological events such as myocardial ischemia. In fact, it is now recognized that autonomic dysregulation is central to the evolution of heart failure and arrhythmias. Autonomic regulation therapy is an emerging modality in the management of acute and chronic cardiac pathologies. Neuromodulation-based approaches that target select nexus points of this hierarchy for cardiac control offer unique opportunities to positively affect therapeutic outcomes via improved efficacy of cardiovascular reflex control. As such, understanding the anatomical and physiological basis for such control is necessary to implement effectively novel neuromodulation therapies. © 2016 American Physiological Society. Compr Physiol 6:1635-1653, 2016.
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Affiliation(s)
- Jeffrey L Ardell
- Los Angeles (UCLA) Cardiac Arrhythmia Center, David Geffen School of Medicine, University of California, Los Angeles, California, USA.,UCLA Neurocardiology Research Center of Excellence, David Geffen School of Medicine, Los Angeles, California, USA
| | - John Andrew Armour
- Los Angeles (UCLA) Cardiac Arrhythmia Center, David Geffen School of Medicine, University of California, Los Angeles, California, USA.,UCLA Neurocardiology Research Center of Excellence, David Geffen School of Medicine, Los Angeles, California, USA
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41
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Tubek S, Niewinski P, Reczuch K, Janczak D, Rucinski A, Paleczny B, Engelman ZJ, Banasiak W, Paton JFR, Ponikowski P. Effects of selective carotid body stimulation with adenosine in conscious humans. J Physiol 2016; 594:6225-6240. [PMID: 27435894 DOI: 10.1113/jp272109] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2016] [Accepted: 07/12/2016] [Indexed: 01/23/2023] Open
Abstract
KEY POINTS In humans, excitation of peripheral chemoreceptors with systemic hypoxia causes hyperventilation, hypertension and tachycardia. However, the contribution of particular chemosensory areas (carotid vs. aortic bodies) to this response is unclear. We showed that selective stimulation of the carotid body by the injection of adenosine into the carotid artery causes a dose-dependent increase in minute ventilation and blood pressure with a concomitant decrease in heart rate in conscious humans. The ventilatory response was abolished and the haemodynamic response was diminished following carotid body ablation. We found that the magnitude of adenosine evoked responses in minute ventilation and blood pressure was analogous to the responses evoked by hypoxia. By contrast, opposing heart rate responses were evoked by adenosine (bradycardia) vs. hypoxia (tachycardia). Intra-carotid adenosine administration may provide a novel method for perioperative assessment of the effectiveness of carotid body ablation, which has been recently proposed as a treatment strategy for sympathetically-mediated diseases. ABSTRACT Stimulation of peripheral chemoreceptors by acute hypoxia causes an increase in minute ventilation (VI), heart rate (HR) and arterial blood pressure (BP). However, the contribution of particular chemosensory areas, such as carotid (CB) vs. aortic bodies, to this response in humans remains unknown. We performed a blinded, randomized and placebo-controlled study in 11 conscious patients (nine men, two women) undergoing common carotid artery angiography. Doses of adenosine ranging from 4 to 512 μg or placebo solution of a matching volume were administered in randomized order via a diagnostic catheter located in a common carotid artery. Separately, ventilatory and haemodynamic responses to systemic hypoxia were also assessed. Direct excitation of a CB with intra-arterial adenosine increased VI, systolic BP, mean BP and decreased HR. No responses in these variables were seen after injections of placebo. The magnitude of the ventilatory and haemodynamic responses depended on both the dose of adenosine used and on the level of chemosensitivity as determined by the ventilatory response to hypoxia. Percutaneous radiofrequency ablation of the CB abolished the adenosine evoked respiratory response and partially depressed the cardiovascular response in one participant. The results of the present study confirm the excitatory role of purines in CB physiology in humans and suggest that adenosine may be used for selective stimulation and assessment of CB activity. The trial is registered at ClinicalTrials.gov NCT01939912.
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Affiliation(s)
- Stanislaw Tubek
- Department of Cardiology, Centre for Heart Diseases, 4th Military Hospital, Wroclaw, Poland. .,Department of Heart Diseases, Faculty of Health Sciences, Wroclaw Medical University, Wroclaw, Poland.
| | - Piotr Niewinski
- Department of Cardiology, Centre for Heart Diseases, 4th Military Hospital, Wroclaw, Poland
| | - Krzysztof Reczuch
- Department of Cardiology, Centre for Heart Diseases, 4th Military Hospital, Wroclaw, Poland.,Department of Heart Diseases, Faculty of Health Sciences, Wroclaw Medical University, Wroclaw, Poland
| | - Dariusz Janczak
- Department of Vascular Surgery, 4th Military Hospital, Wroclaw, Poland.,Department of Clinical Proceedings, Faculty of Health Sciences, Wroclaw Medical University, Wroclaw, Poland
| | - Artur Rucinski
- Department of Vascular Surgery, 4th Military Hospital, Wroclaw, Poland
| | | | | | - Waldemar Banasiak
- Department of Cardiology, Centre for Heart Diseases, 4th Military Hospital, Wroclaw, Poland
| | - Julian F R Paton
- School of Physiology, Pharmacology & Neuroscience, Biomedical Sciences, University of Bristol, Bristol, UK
| | - Piotr Ponikowski
- Department of Cardiology, Centre for Heart Diseases, 4th Military Hospital, Wroclaw, Poland.,Department of Heart Diseases, Faculty of Health Sciences, Wroclaw Medical University, Wroclaw, Poland
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Abstract
Congestive heart failure (CHF) is among the most common causes of admission to hospitals in the United States, especially in those over age 65. Few data exist regarding the prevalence CHF of Cheyne-Stokes respiration (CSR) owing to congestive heart failure in the intensive care unit (ICU). Nevertheless, CSR is expected to be highly prevalent among those with CHF. Treatment should focus on the underlying mechanisms by which CHF increases loop gain and promotes unstable breathing. Few data are available to determine prevalence of CSR in the ICU, or how CSR might affect clinical management and weaning from mechanical ventilation.
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Affiliation(s)
- Scott A Sands
- Division of Sleep Medicine, Brigham and Women's Hospital and Harvard Medical School, 221 Longwood Avenue, Boston, MA 02115, USA; Department of Allergy, Immunology and Respiratory Medicine and Central Clinical School, Alfred Hospital and Monash University, 55 Commercial Rd, Melbourne, VIC 3004, Australia
| | - Robert L Owens
- Division of Pulmonary and Critical Care Medicine, University of California San Diego, 9300 Campus Point Drive, #7381, La Jolla, CA 92037, USA.
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43
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Affiliation(s)
- Julian F R Paton
- School of Physiology, Pharmacology, and Neuroscience, Biomedical Sciences, University of Bristol, Bristol, United Kingdom.
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44
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Mozer MT, Holbein WW, Joyner MJ, Curry TB, Limberg JK. Reductions in carotid chemoreceptor activity with low-dose dopamine improves baroreflex control of heart rate during hypoxia in humans. Physiol Rep 2016; 4:e12859. [PMID: 27418545 PMCID: PMC4945841 DOI: 10.14814/phy2.12859] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2016] [Revised: 06/13/2016] [Accepted: 06/18/2016] [Indexed: 11/24/2022] Open
Abstract
The purpose of the present investigation was to examine the contribution of the carotid body chemoreceptors to changes in baroreflex control of heart rate with exposure to hypoxia. We hypothesized spontaneous cardiac baroreflex sensitivity (scBRS) would be reduced with hypoxia and this effect would be blunted when carotid chemoreceptor activity was reduced with low-dose dopamine. Fifteen healthy adults (11 M/4 F) completed two visits randomized to intravenous dopamine or placebo (saline). On each visit, subjects were exposed to 5-min normoxia (~99% SpO2), followed by 5-min hypoxia (~84% SpO2). Blood pressure (intra-arterial catheter) and heart rate (ECG) were measured continuously and scBRS was assessed by spectrum and sequence methodologies. scBRS was reduced with hypoxia (P < 0.01). Using the spectrum analysis approach, the fall in scBRS with hypoxia was attenuated with infusion of low-dose dopamine (P < 0.01). The decrease in baroreflex sensitivity to rising pressures (scBRS "up-up") was also attenuated with low-dose dopamine (P < 0.05). However, dopamine did not attenuate the decrease in baroreflex sensitivity to falling pressures (scBRS "down-down"; P > 0.05). Present findings are consistent with a reduction in scBRS with systemic hypoxia. Furthermore, we show this effect is partially mediated by the carotid body chemoreceptors, given the fall in scBRS is attenuated when activity of the chemoreceptors is reduced with low-dose dopamine. However, the improvement in scBRS with dopamine appears to be specific to rising blood pressures. These results may have important implications for impairments in baroreflex function common in disease states of acute and/or chronic hypoxemia, as well as the experimental use of dopamine to assess such changes.
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Affiliation(s)
- Michael T Mozer
- Department of Anesthesiology, Mayo Clinic, Rochester, Minnesota
| | | | | | - Timothy B Curry
- Department of Anesthesiology, Mayo Clinic, Rochester, Minnesota
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45
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Toledo C, Andrade DC, Lucero C, Schultz HD, Marcus N, Retamal M, Madrid C, Del Rio R. Contribution of peripheral and central chemoreceptors to sympatho-excitation in heart failure. J Physiol 2016; 595:43-51. [PMID: 27218485 DOI: 10.1113/jp272075] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2015] [Accepted: 04/20/2016] [Indexed: 12/18/2022] Open
Abstract
Chronic heart failure (CHF) is a major public health problem. Tonic hyper-activation of sympathetic neural outflow is commonly observed in patients with CHF. Importantly, sympatho-excitation in CHF exacerbates its progression and is strongly related to poor prognosis and high mortality risk. Increases in both peripheral and central chemoreflex drive are considered markers of the severity of CHF. The principal peripheral chemoreceptors are the carotid bodies (CBs) and alteration in their function has been described in CHF. Mainly, during CHF the CB chemosensitivity is enhanced leading to increases in ventilation and sympathetic outflow. In addition to peripheral control of breathing, central chemoreceptors (CCs) are considered a dominant mechanism in ventilatory regulation. Potentiation of the ventilatory and sympathetic drive in response to CC activation has been shown in patients with CHF as well as in animal models. Therefore, improving understanding of the contribution of the peripheral and central chemoreflexes to augmented sympathetic discharge in CHF could help in developing new therapeutic approaches intended to attenuate the progression of CHF. Accordingly, the main focus of this review is to discuss recent evidence that peripheral and central chemoreflex function are altered in CHF and that they contribute to autonomic imbalance and progression of CHF.
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Affiliation(s)
- Camilo Toledo
- Laboratory of Cardiorespiratory Control, Center of Biomedical Research, Universidad Autónoma de Chile, Santiago, Chile
| | - David C Andrade
- Laboratory of Cardiorespiratory Control, Center of Biomedical Research, Universidad Autónoma de Chile, Santiago, Chile
| | - Claudia Lucero
- Laboratory of Cardiorespiratory Control, Center of Biomedical Research, Universidad Autónoma de Chile, Santiago, Chile
| | - Harold D Schultz
- Department of Cellular and Integrative Physiology, University of Nebraska Medical Center, Omaha, NE, USA
| | - Noah Marcus
- Department of Physiology and Pharmacology, Des Moines University, Des Moines, IA, USA
| | - Mauricio Retamal
- Centro de Fisiología Celular e Integrativa, Facultad de Medicina, Clínica Alemana-Universidad del Desarrollo, Santiago, Chile
| | - Carlos Madrid
- Centro de Fisiología Celular e Integrativa, Facultad de Medicina, Clínica Alemana-Universidad del Desarrollo, Santiago, Chile
| | - Rodrigo Del Rio
- Laboratory of Cardiorespiratory Control, Center of Biomedical Research, Universidad Autónoma de Chile, Santiago, Chile
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46
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Mirizzi G, Giannoni A, Ripoli A, Iudice G, Bramanti F, Emdin M, Passino C. Prediction of the Chemoreflex Gain by Common Clinical Variables in Heart Failure. PLoS One 2016; 11:e0153510. [PMID: 27099934 PMCID: PMC4839709 DOI: 10.1371/journal.pone.0153510] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2015] [Accepted: 03/30/2016] [Indexed: 11/19/2022] Open
Abstract
BACKGROUND Peripheral and central chemoreflex sensitivity, assessed by the hypoxic or hypercapnic ventilatory response (HVR and HCVR, respectively), is enhanced in heart failure (HF) patients, is involved in the pathophysiology of the disease, and is under investigation as a potential therapeutic target. Chemoreflex sensitivity assessment is however demanding and, therefore, not easily applicable in the clinical setting. We aimed at evaluating whether common clinical variables, broadly obtained by routine clinical and instrumental evaluation, could predict increased HVR and HCVR. METHODS AND RESULTS 191 patients with systolic HF (left ventricular ejection fraction--LVEF--<50%) underwent chemoreflex assessment by rebreathing technique to assess HVR and HCVR. All patients underwent clinical and neurohormonal evaluation, comprising: echocardiogram, cardiopulmonary exercise test (CPET), daytime cardiorespiratory monitoring for breathing pattern evaluation. Regarding HVR, multivariate penalized logistic regression, Bayesian Model Averaging (BMA) logistic regression and random forest analysis identified, as predictors, the presence of periodic breathing and increased slope of the relation between ventilation and carbon dioxide production (VE/VCO2) during exercise. Again, the above-mentioned statistical tools identified as HCVR predictors plasma levels of N-terminal fragment of proBNP and VE/VCO2 slope. CONCLUSIONS In HF patients, the simple assessment of breathing pattern, alongside with ventilatory efficiency during exercise and natriuretic peptides levels identifies a subset of patients presenting with increased chemoreflex sensitivity to either hypoxia or hypercapnia.
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Affiliation(s)
- Gianluca Mirizzi
- Department of Cardiology and Cardiovascular Medicine, Fondazione Toscana G. Monasterio, Pisa, Italy
- * E-mail:
| | - Alberto Giannoni
- Department of Cardiology and Cardiovascular Medicine, Fondazione Toscana G. Monasterio, Pisa, Italy
| | - Andrea Ripoli
- Department of Cardiology and Cardiovascular Medicine, Fondazione Toscana G. Monasterio, Pisa, Italy
| | - Giovanni Iudice
- Department of Cardiology and Cardiovascular Medicine, Fondazione Toscana G. Monasterio, Pisa, Italy
| | - Francesca Bramanti
- Department of Cardiology and Cardiovascular Medicine, Fondazione Toscana G. Monasterio, Pisa, Italy
| | - Michele Emdin
- Department of Cardiology and Cardiovascular Medicine, Fondazione Toscana G. Monasterio, Pisa, Italy
- Scuola Superiore Sant’Anna, Pisa, Italy
| | - Claudio Passino
- Department of Cardiology and Cardiovascular Medicine, Fondazione Toscana G. Monasterio, Pisa, Italy
- Scuola Superiore Sant’Anna, Pisa, Italy
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47
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Koeners MP, Lewis KE, Ford AP, Paton JF. Hypertension: a problem of organ blood flow supply-demand mismatch. Future Cardiol 2016; 12:339-49. [PMID: 27091483 PMCID: PMC4926521 DOI: 10.2217/fca.16.5] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023] Open
Abstract
This review introduces a new hypothesis that sympathetically mediated hypertensive diseases are caused, in the most part, by the activation of visceral afferent systems that are connected to neural circuits generating sympathetic activity. We consider how organ hypoperfusion and blood flow supply–demand mismatch might lead to both sensory hyper-reflexia and aberrant afferent tonicity. We discuss how this may drive sympatho-excitatory-positive feedback and extend across multiple organs initiating, or at least amplifying, sympathetic hyperactivity. The latter, in turn, compounds the challenge to sufficient organ blood flow through heightened vasoconstriction that both maintains and exacerbates hypertension.
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Affiliation(s)
- Maarten P Koeners
- School of Physiology, Pharmacology & Neuroscience, Biomedical Sciences, University of Bristol, Bristol, UK
| | - Kirsty E Lewis
- School of Physiology, Pharmacology & Neuroscience, Biomedical Sciences, University of Bristol, Bristol, UK
| | - Anthony P Ford
- Afferent Pharmaceuticals, 2929 Campus Drive, San Mateo, CA, USA
| | - Julian Fr Paton
- School of Physiology, Pharmacology & Neuroscience, Biomedical Sciences, University of Bristol, Bristol, UK
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48
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Niewinski P. Carotid body modulation in systolic heart failure from the clinical perspective. J Physiol 2016; 595:53-61. [PMID: 26990354 DOI: 10.1113/jp271692] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2015] [Accepted: 03/10/2016] [Indexed: 01/30/2023] Open
Abstract
Augmented sensitivity of peripheral chemoreceptors (PChS) is a common finding in systolic heart failure (HF). It is related to lower left ventricle systolic function, higher plasma concentrations of natriuretic peptides, worse exercise tolerance and greater prevalence of atrial fibrillation compared to patients with normal PChS. The magnitude of ventilatory response to the activation of peripheral chemoreceptors is proportional to the level of heart rate (tachycardia) and blood pressure (hypertension) responses. All these responses can be measured non-invasively in a safe and reproducible fashion using different methods employing either hypoxia or hypercapnia. Current interventions aimed at modulation of peripheral chemoreceptors in HF are focused on carotid bodies (CBs). There is a clear link between afferent signalling from CBs and sympathetic overactivity, which remains the priority target of modern HF treatment. However, CB modulation therapies may face several potential obstacles: (1) As evidenced by HF trials, an excessive inhibition of sympathetic system may be harmful. (2) Proximity of critical anatomical structures (important vessels and nerves) makes surgical and transcutaneous interventions on CB technically demanding. (3) Co-existence of atherosclerosis in the area of carotid artery bifurcation increases the risk of central embolic events related to CB modulation. (4) The relative contribution of CBs vs. aortic bodies to sympathetic activation in HF patients is unclear. (5) Choosing optimal candidates for CB modulation from the population of HF patients may be problematic. (6) There is a risk of nocturnal hypoxia following CB ablation - mostly after bilateral procedures and in patients with concomitant obstructive sleep apnoea.
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Affiliation(s)
- Piotr Niewinski
- Cardiology Department, Centre for Heart Diseases, Military Hospital, Wroclaw, Poland
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Jaźwiec P, Gać P, Poręba M, Sobieszczańska M, Mazur G, Poręba R. The volume of the carotid bodies and blood pressure variability and pulse pressure in patients with essential hypertension. Clin Radiol 2016; 71:616.e7-616.e13. [PMID: 27029889 DOI: 10.1016/j.crad.2016.02.022] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2015] [Revised: 02/11/2016] [Accepted: 02/23/2016] [Indexed: 01/03/2023]
Abstract
AIM To assess the relationship between the volume of the carotid bodies (VrCB+lCB) examined by means of computed tomography angiography (CTA) and blood pressure variability and pulse pressure (PP) in 24-hour ambulatory blood pressure monitoring (ABPM) in patients with essential hypertension. MATERIALS AND METHODS A group of 52 patients with essential hypertension was examined (mean age: 68.32±12.31 years), the sizes of carotid bodies were measured by means of carotid artery CTA, and 24-hour ABPM was carried out. The 24-hour ABPM established systolic blood pressure (SBP), diastolic blood pressure (DBP), mean arterial pressure (MAP), PP, SBP variability (SBPV), and DBP variability (DBPV). RESULTS SBP, MAP, and SBPV were significantly higher in the group of hypertension patients with VrCB+lCB equal to or above the median than in the group of hypertension patients with VrCB+lCB less than the median, as well as in the group of hypertension patients with oversized carotid bodies, than in the group of hypertension patients with normal VrCB+lCB. Moreover, the PP was statistically significantly higher in the group of hypertension patients with VrCB+lCB equal to or above the median than in the group of hypertension patients with VrCB+lCB less than the median. The existence of statistically significant positive linear relationships was revealed between VrCB+lCB and SBP, PP, and SBPV. A higher body mass index, older age, smoking, and higher VrCB+lCB are independent risk factors increasing SBPV in the research group. CONCLUSION A positive relationship between the size of the carotid bodies and variability of the SBP and PP is observed in patients with essential hypertension.
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Affiliation(s)
- P Jaźwiec
- Department of Radiology and Diagnostic Imaging, 4th Military Hospital, Weigla 5, PL 50-981 Wroclaw, Poland
| | - P Gać
- Department of Radiology and Diagnostic Imaging, 4th Military Hospital, Weigla 5, PL 50-981 Wroclaw, Poland.
| | - M Poręba
- Department of Pathophysiology, Wroclaw Medical University, Marcinkowskiego 1, PL 50-368 Wroclaw, Poland
| | - M Sobieszczańska
- Department of Pathophysiology, Wroclaw Medical University, Marcinkowskiego 1, PL 50-368 Wroclaw, Poland
| | - G Mazur
- Department of Internal Medicine, Occupational Diseases and Hypertension, Wroclaw Medical University, Borowska 213, PL 50-556 Wroclaw, Poland
| | - R Poręba
- Department of Internal Medicine, Occupational Diseases and Hypertension, Wroclaw Medical University, Borowska 213, PL 50-556 Wroclaw, Poland
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Giannoni A, Mirizzi G, Aimo A, Emdin M, Passino C. Peripheral reflex feedbacks in chronic heart failure: Is it time for a direct treatment? World J Cardiol 2015; 7:824-828. [PMID: 26730288 PMCID: PMC4691809 DOI: 10.4330/wjc.v7.i12.824] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/30/2015] [Revised: 09/21/2015] [Accepted: 10/27/2015] [Indexed: 02/07/2023] Open
Abstract
Despite repeated attempts to develop a unifying hypothesis that explains the clinical syndrome of heart failure (HF), no single conceptual paradigm for HF has withstood the test of time. The last model that has been developed, the neurohormonal model, has the great virtue of highlighting the role of the heart as an endocrine organ, as well as to shed some light on the key role on HF progression of neurohormones and peripheral organs and tissues beyond the heart itself. However, while survival in clinical trials based on neurohormonal antagonist drugs has improved, HF currently remains a lethal condition. At the borders of the neurohormonal model of HF, a partially unexplored path trough the maze of HF pathophysiology is represented by the feedback systems. There are several evidences, from both animal studies and humans reports, that the deregulation of baro-, ergo- and chemo-reflexes in HF patients elicits autonomic imbalance associated with parasympathetic withdrawal and increased adrenergic drive to the heart, thus fundamentally contributing to the evolution of the disease. Hence, on top of guideline-recommended medical therapy, mainly based on neurohormonal antagonisms, all visceral feedbacks have been recently considered in HF patients as additional potential therapeutic targets.
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