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Bunsawat K, Ratchford SM, Alpenglow JK, Stehlik J, Smith AS, Richardson RS, Wray DW. Sympathoinhibitory effect of sacubitril-valsartan in heart failure with reduced ejection fraction: A pilot study. Auton Neurosci 2021; 235:102834. [PMID: 34186274 DOI: 10.1016/j.autneu.2021.102834] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2021] [Revised: 05/07/2021] [Accepted: 06/13/2021] [Indexed: 01/08/2023]
Abstract
Chronic sympathetic nervous system (SNS) overactivity, characteristic of heart failure (HF) with reduced ejection fraction (HFrEF), is associated with poor prognosis and contributes to increased mortality risk. Sacubitril-valsartan is a recently approved, first-in-class, angiotensin receptor neprilysin inhibitor (ARNI) drug that markedly reduces the risks of death from cardiovascular causes and hospitalization for HF in patients with HFrEF, but the physiological mechanisms underlying these benefits are not fully understood. This single-arm, open-label, prospective study sought to test the hypothesis that short-term treatment with sacubitril-valsartan reduces SNS activity, measured directly via muscle sympathetic nerve activity (MSNA), in patients with HFrEF. MSNA, heart rate (HR), and arterial blood pressure (BP) were assessed in stable Class II and III patients with HFrEF (n = 9, 69 ± 8 yrs.; 28.6 ± 3.6 kg/m2) on contemporary, guideline-directed medical treatment who were subsequently started on sacubitril-valsartan. These measurements were repeated after two months of treatment with sacubitril-valsartan. Sacubitril-valsartan reduced MSNA burst frequency (baseline: 43 ± 10 bursts/min; 2-month: 36 ± 10 bursts/min, p = 0.05) and burst incidence (baseline: 68 ± 16 bursts/100 heartbeats; 2-month: 55 ± 16 bursts/100 heartbeats, p = 0.02), while HR and BP were unchanged following of treatment (p > 0.05). These preliminary findings provide new evidence regarding the ability of sacubitril-valsartan to rapidly reduce SNS activity in patients with HFrEF, suggesting the presence of a novel sympathoinhibitory effect of this new drug class.
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Affiliation(s)
- Kanokwan Bunsawat
- Department of Internal Medicine, Division of Geriatrics, University of Utah, Salt Lake City, UT, United States of America.
| | - Stephen M Ratchford
- Department of Internal Medicine, Division of Geriatrics, University of Utah, Salt Lake City, UT, United States of America; Geriatric Research, Education, and Clinical Center, George E. Wahlen Department of Veterans Affairs Medical Center, Salt Lake City, UT, United States of America; Department of Health and Exercise Science, Appalachian State University, Boone, NC, United States of America
| | - Jeremy K Alpenglow
- Department of Nutrition and Integrative Physiology, University of Utah, Salt Lake City, UT, United States of America
| | - Josef Stehlik
- Department of Internal Medicine, Division of Cardiovascular Medicine, University of Utah, Salt Lake City, UT, United States of America
| | - Adam S Smith
- Department of Pharmacy Services, University of Utah, Salt Lake City, UT, United States of America
| | - Russell S Richardson
- Department of Internal Medicine, Division of Geriatrics, University of Utah, Salt Lake City, UT, United States of America; Geriatric Research, Education, and Clinical Center, George E. Wahlen Department of Veterans Affairs Medical Center, Salt Lake City, UT, United States of America; Department of Nutrition and Integrative Physiology, University of Utah, Salt Lake City, UT, United States of America
| | - D Walter Wray
- Department of Internal Medicine, Division of Geriatrics, University of Utah, Salt Lake City, UT, United States of America; Geriatric Research, Education, and Clinical Center, George E. Wahlen Department of Veterans Affairs Medical Center, Salt Lake City, UT, United States of America; Department of Nutrition and Integrative Physiology, University of Utah, Salt Lake City, UT, United States of America
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Chen W, Shen J, Chen R, You H, Ye F, Zheng J, Lu L, Lu X, Ni J, Wu Y, Qiao Z. Amelioration of ischemic cardiomyopathy in patients using physiological ischemic training. Herz 2020; 46:173-179. [PMID: 32886131 DOI: 10.1007/s00059-020-04975-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2020] [Revised: 07/01/2020] [Accepted: 08/01/2020] [Indexed: 10/23/2022]
Abstract
BACKGROUND This study aimed to observe the effect and potential mechanism of physiological ischemic training (PIT) in patients with ischemic cardiomyopathy. METHODS A total of 165 patients with ischemic cardiomyopathy were randomly selected by the convenience sampling method and were divided into the control and experimental groups. The control group received conventional drug treatment, while the experimental group received additional PIT. All patients were followed up for 6 months and renin-angiotensin-aldosterone system (RAS) activity parameters and myocardial remodeling indicators were recorded. RESULTS After the 6‑month intervention, cardiac function indicators in the two groups were significantly improved compared with before intervention (all P < 0.01), but the experimental group showed significantly more improvement compared with the control group (all P < 0.01). Similarly, RAS activity parameters and myocardial remodeling indicators of the two groups were significantly reduced after intervention compared with before intervention (all P < 0.01). However, the experimental group showed significantly lower myocardial remodeling indicators than the control group (all P < 0.01). Vascular endothelial growth factor (VEGF) and nitric oxide (NO) concentrations in peripheral blood in the experimental group were significantly increased after intervention compared with before intervention (both P < 0.01). CONCLUSIONS PIT can be applied in patients with ischemic cardiomyopathy on the basis of the original standardized drug treatment. PIT ameliorates cardiac blood flow reserve by increasing VEGF and NO concentrations in the peripheral blood, as well as by inhibiting the RAS system and myocardial remodeling. This ultimately improves the patient's cardiac function to a greater extent.
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Affiliation(s)
- Weihai Chen
- Department of Cardiology, Suzhou Ninth People's Hospital, Affiliated Wujiang Hospital of Nantong University, Ludang Road, 2666, Suzhou, China
| | - Jun Shen
- Department of Cardiology, Suzhou Ninth People's Hospital, Affiliated Wujiang Hospital of Nantong University, Ludang Road, 2666, Suzhou, China
| | - Rongrong Chen
- Department of Geriatric Medicine, Suzhou Municipal Hospital, Suzhou Cancer Medical Center, Affiliated Suzhou Hospital of Nanjing Medical University, Suzhou, China
| | - Hua You
- Department of Cardiology, Suzhou Ninth People's Hospital, Affiliated Wujiang Hospital of Nantong University, Ludang Road, 2666, Suzhou, China
| | - Fulong Ye
- Department of Cardiology, Suzhou Ninth People's Hospital, Affiliated Wujiang Hospital of Nantong University, Ludang Road, 2666, Suzhou, China
| | - Ju Zheng
- Department of Cardiology, Suzhou Ninth People's Hospital, Affiliated Wujiang Hospital of Nantong University, Ludang Road, 2666, Suzhou, China
| | - Lijuan Lu
- Department of Gynecology and Obstetrics, Suzhou Hospital of Traditional Chinese Medicine, Suzhou, China
| | - Xiao Lu
- Department of Rehabilitation, The First Affiliated Hospital of Nanjing Medical University, Nanjing, China
| | - Jun Ni
- Department of Rehabilitation, Affiliated Hospital of Nantong University, Nantong, China
| | - Yanming Wu
- Department of Cardiology, Suzhou Ninth People's Hospital, Affiliated Wujiang Hospital of Nantong University, Ludang Road, 2666, Suzhou, China.
| | - Zhenguo Qiao
- Department of Gastroenterology, Suzhou Ninth People's Hospital, Affiliated Wujiang Hospital of Nantong University, 2666 Ludang Road, 215200, Suzhou, China.
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Ruzicka M, Knoll G, Leenen FHH, Leech J, Aaron SD, Hiremath S. Effects of CPAP on Blood Pressure and Sympathetic Activity in Patients With Diabetes Mellitus, Chronic Kidney Disease, and Resistant Hypertension. CJC Open 2020; 2:258-264. [PMID: 32695977 PMCID: PMC7365815 DOI: 10.1016/j.cjco.2020.03.010] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2020] [Accepted: 03/19/2020] [Indexed: 12/19/2022] Open
Abstract
Background Patients with obstructive sleep apnea (OSA) have increased sympathetic activity and frequently also have resistant hypertension (HTN). Treatment of OSA with continuous positive airway pressure (CPAP) decreases awake and sleep blood pressure (BP) and sympathetic activity. This study was designed to assess the effect of treatment of OSA with CPAP on sympathetic activity and BP in patients with diabetes mellitus (DM), chronic kidney disease (CKD), and resistant HTN. Methods This was a randomized, double-blind, sham-controlled trial. Patients with DM, CKD, and resistant HTN were randomized to treatment with a therapeutic or subtherapeutic CPAP for 6 weeks. They underwent 24-hour ambulatory BP monitoring and assessment of muscle sympathetic nerve activity before and after 6 weeks on treatment. Results Treatment with therapeutic CPAP caused significant decreases in awake systolic and diastolic BP from 144 to 136 mm Hg (P = 0.004) and from 79 to 74 mm Hg (P = 0.004) and in sleep BP from 135 to 119 mm Hg (P = 0.045) and from 75 to 65 mm Hg (P = 0.015) compared with treatment with subtherapeutic CPAP. In contrast, treatment with therapeutic CPAP did not decrease sympathetic activity as assessed from muscle sympathetic nerve activity. Conclusions Decrease in BP by treatment with CPAP in patients with DM, CKD, and OSA indicates the contribution of OSA to severity of HTN in this clinical scenario. Decrease in BP in the absence of changes in sympathetic activity is suggestive that other mechanisms induced by OSA play a larger role in the maintenance of HTN in these patients.
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Affiliation(s)
- Marcel Ruzicka
- Division of Nephrology, Department of Medicine, University of Ottawa, Ottawa, Ontario, Canada
| | - Greg Knoll
- Division of Nephrology, Department of Medicine, University of Ottawa, Ottawa, Ontario, Canada
| | - Frans H H Leenen
- Division of Cardiology, Department of Medicine, University of Ottawa Heart Institute, Ottawa, Ontario, Canada
| | - Judith Leech
- Division of Respirology, Department of Medicine, University of Ottawa, Ottawa, Ontario, Canada
| | - Shawn D Aaron
- Division of Respirology, Department of Medicine, University of Ottawa, Ottawa, Ontario, Canada
| | - Swapnil Hiremath
- Division of Nephrology, Department of Medicine, University of Ottawa, Ottawa, Ontario, Canada
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Sympathetic neural overdrive in congestive heart failure and its correlates: systematic reviews and meta-analysis. J Hypertens 2020; 37:1746-1756. [PMID: 30950979 DOI: 10.1097/hjh.0000000000002093] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
BACKGROUND AND OBJECTIVES Sympathetic neural activation occurs in congestive heart failure (CHF). However, the small sample size of the microneurographic studies, heterogeneity of the patients examined, presence of comorbidities as well as confounders (including treatment) represented major weaknesses not allowing to identify the major features of the phoenomenon, particularly in mild CHF. This meta-analysis evaluated 2530 heart failure (CHF) patients recruited in 106 microneurographic studies. It was based on muscle sympathetic nerve activity (MSNA) quantification in CHF of different clinical severity, but data from less widely addressed conditions, such as ischemic vs. idiopathic, were also considered. METHODS Assessment was extended to the relationships of MSNA with venous plasma norepinephrine, heart rate (HR) and echocardiographic parameters of cardiac morphology [left ventricular (LV) end-diastolic diameter] and function (LV ejection fraction) as well. RESULTS MSNA was significantly greater (1.9 times, P < 0.001) in CHF patients as compared with healthy controls, a progressive significant increase being observed from New York Heart Association classes I-IV in unadjusted and adjusted analyses. MSNA was significantly greater in both untreated and treated CHF (P < 0.001 for both), related to left ventricular (LV) end-diastolic diameter and to a lesser extent to LV ejection fraction (r = 0.24 and -0.05, P < 0.001 and <0.01, respectively), and closely associated with HR (r = 0.66, P < 0.001) and plasma norepinephrine (r = 0.68, P < 0.001). CONCLUSION CHF is characterized by sympathetic overactivity which mirrors the degree of LV dysfunction independently of the stage of CHF, its cause and presence of confounders or pharmacological treatment. plasma norepinephrine and HR represent potentially valuable surrogate markers of sympathetic activation in the clinical setting.
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Brooks VL, Fu Q, Shi Z, Heesch CM. Adaptations in autonomic nervous system regulation in normal and hypertensive pregnancy. HANDBOOK OF CLINICAL NEUROLOGY 2020; 171:57-84. [PMID: 32736759 DOI: 10.1016/b978-0-444-64239-4.00003-5] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
There is an increase in basal sympathetic nerve activity (SNA) during normal pregnancy; this counteracts profound primary vasodilation. However, pregnancy also impairs baroreflex control of heart rate and SNA, contributing to increased mortality secondary to peripartum hemorrhage. Pregnancy-induced hypertensive disorders evoke even greater elevations in SNA, which likely contribute to the hypertension. Information concerning mechanisms is limited. In normal pregnancy, increased angiotensin II acts centrally to support elevated SNA. Hypothalamic sites, including the subfornical organ, paraventricular nucleus, and arcuate nucleus, are likely (but unproven) targets. Moreover, no definitive mechanisms for exaggerated sympathoexcitation in hypertensive pregnancy have been identified. In addition, normal pregnancy increases gamma aminobutyric acid inhibition of the rostral ventrolateral medulla (RVLM), a key brainstem site that transmits excitatory inputs to spinal sympathetic preganglionic neurons. Accumulated evidence supports a major role for locally increased production and actions of the neurosteroid allopregnanolone as one mechanism. A consequence is suppression of baroreflex function, but increased basal SNA indicates that excitatory influences predominate in the RVLM. However, many questions remain regarding other sites and factors that support increased SNA during normal pregnancy and, more importantly, the mechanisms underlying excessive sympathoexcitation in life-threatening hypertensive pregnancy disorders such as preeclampsia.
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Affiliation(s)
- Virginia L Brooks
- Department of Physiology and Pharmacology, Oregon Health & Science University, Portland, OR, United States.
| | - Qi Fu
- Institute for Exercise and Environmental Medicine, Texas Health Presbyterian Hospital Dallas, Dallas, TX, United States; Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, TX, United States
| | - Zhigang Shi
- Department of Physiology and Pharmacology, Oregon Health & Science University, Portland, OR, United States
| | - Cheryl M Heesch
- Department of Biomedical Sciences and Dalton Cardiovascular Research Center, University of Missouri, Columbia, MO, United States
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Oatmen KE, Zile MR, Burnett JC, Spinale FG. Bioactive Signaling in Next-Generation Pharmacotherapies for Heart Failure: A Review. JAMA Cardiol 2019; 3:1232-1243. [PMID: 30484834 DOI: 10.1001/jamacardio.2018.3789] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
Importance The standard pharmacotherapy for heart failure (HF), particularly HF with reduced ejection fraction (HFrEF), is primarily through the use of receptor antagonists, notably inhibition of the renin-angiotensin system by either angiotensin-converting enzyme inhibition or angiotensin II receptor blockade (ARB). However, the completed Prospective Comparison of ARNI With an ACE-Inhibitor to Determine Impact on Global Mortality and Morbidity in Heart Failure (PARADIGM-HF) trial identified that the use of a single molecule (sacubitril/valsartan), which is an ARB and the neutral endopeptidase inhibitor (NEPi) neprilysin, yielded improved clinical outcomes in HFrEF compared with angiotensin-converting enzyme inhibition alone. Observations This review examined specific bioactive signaling pathways that would be potentiated by NEPi and how these would affect key cardiovascular processes relevant to HFrEF. It also addressed potential additive/synergistic effects of ARB. A number of biological signaling pathways that may be potentiated by sacubitril/valsartan were identified, including some novel candidate molecules, which will act in a synergistic manner to favorably alter the natural history of HFrEF. Conclusions and Relevance This review identified that activation rather than inhibition of specific receptor pathways provided favorable cardiovascular effects that cannot be achieved by renin-angiotensin system inhibition alone. Thus, an entirely new avenue of translational and clinical research lies ahead in which HF pharmacotherapies will move beyond receptor antagonist strategies.
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Affiliation(s)
- Kelsie E Oatmen
- Cardiovascular Translational Research Center, University of South Carolina School of Medicine, Columbia
| | - Michael R Zile
- Medical University of South Carolina, Charleston.,Ralph H. Johnson Department of VA Medical Center, Charleston, South Carolina
| | - John C Burnett
- Cardiorenal Research Laboratory, Mayo Clinic, Rochester, Minnesota
| | - Francis G Spinale
- Cardiovascular Translational Research Center, University of South Carolina School of Medicine, Columbia.,William Jennings Bryan Dorn VA Medical Center, Columbia, South Carolina
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Leversha S, Allen AM, May CN, Ramchandra R. Intrathecal Administration of Losartan Reduces Directly Recorded Cardiac Sympathetic Nerve Activity in Ovine Heart Failure. Hypertension 2019; 74:896-902. [PMID: 31378100 DOI: 10.1161/hypertensionaha.119.12937] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Early and preferential activation of cardiac sympathetic nerve activity (CSNA) is one of the strongest prognostic markers of heart failure (HF) in patients. Our previous studies have implicated central angiotensin mechanisms as playing a critical role in generating this increase in cardiac sympathetic drive. However, it is unclear if inhibition of AT1R (angiotensin type-1 receptors) in different neural groups in the sympathetic pathway to the heart, such as the sympathetic preganglionic neurons in the intermediolateral column of the spinal cord, can reduce cardiac sympathetic drive. We hypothesized that in HF, localized intrathecal administration of the AT1R antagonist losartan, specifically into the T1-2 subarachnoid space, would decrease CSNA. In normal conscious sheep, intrathecal infusion of Ang II (angiotensin II; 3.0 nmol/mL per hour), significantly increased mean arterial pressure and CSNA; this effect was abolished by prior administration of losartan (1 mg/h). In an ovine rapid ventricular pacing model of HF, the resting levels of heart rate and CSNA were significantly elevated compared with normals. Intrathecal infusion of losartan (1 mg/h) in HF significantly reduced CSNA and heart rate but did not change arterial pressure. The AT1R binding density in the spinal cord was also elevated in the HF group. Our data suggest that AT1Rs within the spinal cord are responsible, in part, for the increased CSNA in HF and may represent a target for the selective reduction of CSNA in HF.
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Affiliation(s)
- Simon Leversha
- From the Florey Institute of Neuroscience and Mental Health (S.L., C.N.M., R.R.), University of Melbourne, Parkville, Australia.,Department of Physiology (S.L., A.M.A.), University of Melbourne, Parkville, Australia
| | - Andrew M Allen
- Department of Physiology (S.L., A.M.A.), University of Melbourne, Parkville, Australia
| | - Clive N May
- From the Florey Institute of Neuroscience and Mental Health (S.L., C.N.M., R.R.), University of Melbourne, Parkville, Australia
| | - Rohit Ramchandra
- From the Florey Institute of Neuroscience and Mental Health (S.L., C.N.M., R.R.), University of Melbourne, Parkville, Australia.,Department of Physiology, University of Auckland, New Zealand (R.R.)
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Lu J, Wang HW, Ahmad M, Keshtkar-Jahromi M, Blaustein MP, Hamlyn JM, Leenen FHH. Central and peripheral slow-pressor mechanisms contributing to Angiotensin II-salt hypertension in rats. Cardiovasc Res 2019; 114:233-246. [PMID: 29126194 DOI: 10.1093/cvr/cvx214] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/19/2017] [Accepted: 11/07/2017] [Indexed: 12/17/2022] Open
Abstract
Aims High salt intake markedly enhances hypertension induced by angiotensin II (Ang II). We explored central and peripheral slow-pressor mechanisms which may be activated by Ang II and salt. Methods and results In protocol I, Wistar rats were infused subcutaneously with low-dose Ang II (150 ng/kg/min) and fed regular (0.4%) or high salt (2%) diet for 14 days. In protocol II, Ang II-high salt was combined with intracerebroventricular infusion of mineralocorticoid receptor (MR) blockers (eplerenone, spironolactone), epithelial sodium channel (ENaC) blocker (benzamil), angiotensin II type 1 receptor (AT1R) blocker (losartan) or vehicles. Ang II alone raised mean arterial pressure (MAP) ∼10 mmHg, but Ang II-high salt increased MAP ∼50 mmHg. Ang II-high salt elevated plasma corticosterone, aldosterone and endogenous ouabain but not Ang II alone. Both Ang II alone and Ang II-high salt increased mRNA and protein expression of CYP11B2 (aldosterone synthase gene) in the adrenal cortex but not of CYP11B1 (11-β-hydroxylase gene). In the aorta, Ang II-high salt increased sodium-calcium exchanger-1 (NCX1) protein. The Ang II-high salt induced increase in MAP was largely prevented by central infusion of MR blockers, benzamil or losartan. Central blockades significantly lowered plasma aldosterone and endogenous ouabain and markedly decreased Ang II-high salt induced CYP11B2 mRNA expression in the adrenal cortex and NCX1 protein in the aorta. Conclusion These results suggest that in Ang II-high salt hypertension, MR-ENaC-AT1R signalling in the brain increases circulating aldosterone and endogenous ouabain, and arterial NCX1. These factors can amplify blood pressure responses to centrally-induced sympatho-excitation and thereby contribute to severe hypertension.
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Affiliation(s)
- Jiao Lu
- Brain and Heart Research Group, University of Ottawa Heart Institute, 40 Ruskin Street, Ottawa, ON K1Y 4W7, Canada
| | - Hong-Wei Wang
- Brain and Heart Research Group, University of Ottawa Heart Institute, 40 Ruskin Street, Ottawa, ON K1Y 4W7, Canada
| | - Monir Ahmad
- Brain and Heart Research Group, University of Ottawa Heart Institute, 40 Ruskin Street, Ottawa, ON K1Y 4W7, Canada
| | - Marzieh Keshtkar-Jahromi
- Brain and Heart Research Group, University of Ottawa Heart Institute, 40 Ruskin Street, Ottawa, ON K1Y 4W7, Canada.,Department of Physiology, University of Maryland School of Medicine, 655 West Baltimore S, Baltimore, MD 21201, USA
| | - Mordecai P Blaustein
- Department of Physiology, University of Maryland School of Medicine, 655 West Baltimore S, Baltimore, MD 21201, USA.,Department of Medicine, University of Maryland School of Medicine, 655 West Baltimore S, Baltimore, MD 21201, USA
| | - John M Hamlyn
- Department of Physiology, University of Maryland School of Medicine, 655 West Baltimore S, Baltimore, MD 21201, USA
| | - Frans H H Leenen
- Brain and Heart Research Group, University of Ottawa Heart Institute, 40 Ruskin Street, Ottawa, ON K1Y 4W7, Canada
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Specific Inhibition of Brain Angiotensin III Formation as a New Strategy for Prevention of Heart Failure After Myocardial Infarction. J Cardiovasc Pharmacol 2019; 73:82-91. [DOI: 10.1097/fjc.0000000000000638] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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10
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Increased cardiac sympathetic nerve activity in ovine heart failure is reduced by lesion of the area postrema, but not lamina terminalis. Basic Res Cardiol 2018; 113:35. [DOI: 10.1007/s00395-018-0695-9] [Citation(s) in RCA: 46] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/06/2018] [Revised: 07/30/2018] [Accepted: 08/01/2018] [Indexed: 12/15/2022]
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Restoration of normal sympathetic neural function in heart failure following baroreflex activation therapy: final 43-month study report. J Hypertens 2018; 35:2532-2536. [PMID: 28816745 PMCID: PMC5673301 DOI: 10.1097/hjh.0000000000001498] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
Background: Baroreflex activation therapy (BAT) exerts in severe heart failure sympathoinhibitory effects, improving clinical variables and reducing hospitalization rate. The current follow-up study was aimed at determining the long-term effects of BAT, assessing whether BAT in heart failure allows to restore physiological levels of sympathetic function. Methods: Seven patients out of the 11 heart failure patients aged 66.5 ± 3 years (mean ± SEM) in New York Heart Association Class III with left ventricular ejection fraction 40% or less and impaired functional capacity recruited in the study survived at the final follow-up (43.5 ± 2.1 months). Measurements included muscle sympathetic nerve activity (MSNA, microneurography) and spontaneous baroreflex-MSNA sensitivity together with hospitalization rate, echocardiography, Minnesota score, New York Heart Association class and standard clinical data. Measurements were collected before and at 6, 21 and 43 months following BAT. Data were compared with those collected in 17 age-matched healthy controls. All assessments were made with the heart failure patient on optimal active therapy. Results: In the seven patients, BAT maintained its beneficial effects over 43.5 ± 2.1 months of follow-up. MSNA values underwent a progressive significant reduction from baseline to 21 and 43 months follow-up following BAT (from 46.2 ± 2.4 to 31.3 ± 3.0 e 26.6 ± 2.0 bursts/min, P < 0.05 at least), becoming almost superimposable to the ones seen in healthy controls (25.5 ± 0.8 bursts/min). Baroreflex-MSNA sensitivity improved, without achieving, however, a full normalization. Blood pressure and heart rate did not change. Left ventricular ejection fraction improved significantly from 32.3 ± 2 to 36.7 ± 3% (P < 0.05). Hospitalization rate decreased substantially when measured as days/year/patients it decreased from 10.3 ± 2.5 preimplant to 1.01 ± 1.4 at the 43.5th month follow-up (P < 0.02). No side effects were reported in the long-term period. Conclusion: The current study provides evidence that BAT in heart failure with reduced ejection fraction allows not only to improve hemodynamic and clinical profile but also to exert profound sympathoinhibitory effects, allowing an almost complete restoration of physiological levels of the sympathetic neural function.
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Cooper SG, Trivedi DP, Yamamoto R, Worker CJ, Feng CY, Sorensen JT, Yang W, Xiong Z, Feng Y. Increased (pro)renin receptor expression in the subfornical organ of hypertensive humans. Am J Physiol Heart Circ Physiol 2017; 314:H796-H804. [PMID: 29351470 DOI: 10.1152/ajpheart.00616.2017] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
The central nervous system plays an important role in essential hypertension in humans and in animal models of hypertension through modulation of sympathetic activity and Na+ and body fluid homeostasis. Data from animal models of hypertension suggest that the renin-angiotensin system in the subfornical organ (SFO) of the brain is critical for hypertension development. We recently reported that the brain (pro)renin receptor (PRR) is a novel component of the brain renin-angiotensin system and could be a key initiator of the pathogenesis of hypertension. Here, we examined the expression level and cellular distribution of PRR in the SFO of postmortem human brains to assess its association with the pathogenesis of human hypertension. Postmortem SFO tissues were collected from hypertensive and normotensive human subjects. Immunolabeling for the PRR and a retrospective analysis of clinical data were performed. We found that human PRR was prominently expressed in most neurons and microglia, but not in astrocytes, in the SFO. Importantly, PRR levels in the SFO were elevated in hypertensive subjects. Moreover, PRR immunoreactivity was significantly correlated with systolic blood pressure but not body weight, age, or diastolic blood pressure. Interestingly, this correlation was independent of antihypertensive drug therapy. Our data indicate that PRR in the SFO may be a key molecular player in the pathogenesis of human hypertension and, as such, could be an important focus of efforts to understand the neurogenic origin of hypertension. NEW & NOTEWORTHY This study provides evidence that, in the subfornical organ of the human brain, the (pro)renin receptor is expressed in neurons and microglia cells but not in astrocytes. More importantly, (pro)renin receptor immunoreactivity in the subfornical organ is increased in hypertensive humans and is significantly correlated with systolic blood pressure.
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Affiliation(s)
- Silvana G Cooper
- Departments of Pharmacology, Physiology, and Cell Biology; Center for Cardiovascular Research, School of Medicine, University of Nevada , Reno, Nevada
| | - Darshan P Trivedi
- Department of Pathology, Tulane University School of Medicine , New Orleans, Louisiana
| | - Rieko Yamamoto
- Departments of Pharmacology, Physiology, and Cell Biology; Center for Cardiovascular Research, School of Medicine, University of Nevada , Reno, Nevada.,Tokyo Medical and Dental University, Faculty of Medicine , Tokyo , Japan
| | - Caleb J Worker
- Departments of Pharmacology, Physiology, and Cell Biology; Center for Cardiovascular Research, School of Medicine, University of Nevada , Reno, Nevada
| | - Cheng-Yuan Feng
- Departments of Pharmacology, Physiology, and Cell Biology; Center for Cardiovascular Research, School of Medicine, University of Nevada , Reno, Nevada
| | - Jacob T Sorensen
- Departments of Pharmacology, Physiology, and Cell Biology; Center for Cardiovascular Research, School of Medicine, University of Nevada , Reno, Nevada
| | - Wei Yang
- School of Community Health Sciences, University of Nevada , Reno, Nevada
| | - Zhenggang Xiong
- Department of Pathology, Tulane University School of Medicine , New Orleans, Louisiana
| | - Yumei Feng
- Departments of Pharmacology, Physiology, and Cell Biology; Center for Cardiovascular Research, School of Medicine, University of Nevada , Reno, Nevada
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Welch V, Doull M, Yoganathan M, Jull J, Boscoe M, Coen SE, Marshall Z, Pardo JP, Pederson A, Petkovic J, Puil L, Quinlan L, Shea B, Rader T, Runnels V, Tudiver S. Reporting of sex and gender in randomized controlled trials in Canada: a cross-sectional methods study. Res Integr Peer Rev 2017; 2:15. [PMID: 29451565 PMCID: PMC5803639 DOI: 10.1186/s41073-017-0039-6] [Citation(s) in RCA: 36] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2017] [Accepted: 06/26/2017] [Indexed: 11/21/2022] Open
Abstract
BACKGROUND Accurate reporting on sex and gender in health research is integral to ensuring that health interventions are safe and effective. In Canada and internationally, governments, research organizations, journal editors, and health agencies have called for more inclusive research, provision of sex-disaggregated data, and the integration of sex and gender analysis throughout the research process. Sex and gender analysis is generally defined as an approach for considering how and why different subpopulations (e.g., of diverse genders, ages, and social locations) may experience health conditions and interventions in different or similar ways.The objective of this study was to assess the extent and nature of reporting about sex and/or gender, including whether sex and gender analysis (SGA) was carried out in a sample of Canadian randomized controlled trials (RCTs) with human participants. METHODS We searched MEDLINE from 01 January 2013 to 23 July 2014 using a validated filter for identification of RCTs, combined with terms related to Canada. Two reviewers screened the search results to identify the first 100 RCTs that were either identified in the trial publication as funded by a Canadian organization or which had a first or last author based in Canada. Data were independently extracted by two people from 10% of the RCTs during an initial training period; once agreement was reached on this sample, the remainder of the data extraction was completed by one person and verified by a second. RESULTS The search yielded 1433 records. We screened 256 records to identify 100 RCTs which met our eligibility criteria. The median sample size of the RCTs was 107 participants (range 12-6085). While 98% of studies described the demographic composition of their participants by sex, only 6% conducted a subgroup analysis across sex and 4% reported sex-disaggregated data. No article defined "sex" and/or "gender." No publication carried out a comprehensive sex and gender analysis. CONCLUSIONS Findings highlight poor uptake of sex and gender considerations in the Canadian RCT context and underscore the need for better articulated guidance on sex and gender analysis to improve reporting of evidence, inform policy development, and guide future research.
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Affiliation(s)
- V. Welch
- Bruyère Research Institute, Bruyère Continuing Care, 304b-85 Primrose Avenue, Ottawa, Ontario K1R 6 M1 Canada
- University of Ottawa, Ontario, Canada
| | - M. Doull
- School of Nursing, University of British Columbia, T223-2211 Wesbrook Mall, Vancouver, British Columbia V6T 2B5 Canada
| | - M. Yoganathan
- Bruyère Research Institute, Bruyère Continuing Care, 304b-85 Primrose Avenue, Ottawa, Ontario K1R 6 M1 Canada
| | - J. Jull
- Ottawa Hospital Research Institute, University of Ottawa, Ottawa, Ontario Canada
| | - M. Boscoe
- Research Sex/gender, Health Equity, Primary Care Consultant, 906 Bowron Court, North Vancouver, BC V7H 2S7 Canada
| | - S. E. Coen
- Department of Geography and Planning, Queen’s University, Mackintosh-Corry Hall, Kingston, Ontario K7L 3 N6 Canada
| | - Z. Marshall
- Renison University College, University of Waterloo, 240 Westmount Road North, Waterloo, Ontario N2L 3G4 Canada
| | - J. Pardo Pardo
- Cochrane Musculoskeletal, University of Ottawa, Ottawa Hospital Research Institute, The Ottawa Hospital, General Campus, 501 Smyth Road, Ottawa, ON K1H 8L6 Canada
| | - A. Pederson
- B.C. Women’s Hospital + Health Centre, E305, 4500 Oak Street, Vancouver, BC V6H 3E1 Canada
| | - J. Petkovic
- Bruyère Research Institute, Bruyère Continuing Care, 304b-85 Primrose Avenue, Ottawa, Ontario K1R 6 M1 Canada
- University of Ottawa, Ontario, Canada
| | - L. Puil
- Department of Anesthesiology, Pharmacology & Therapeutics, Faculty of Medicine, University of British Columbia, 2176 Health Sciences Mall, Vancouver, BC V6T 1Z3 Canada
| | - L. Quinlan
- Bruyère Research Institute, Bruyère Continuing Care, 304b-85 Primrose Avenue, Ottawa, Ontario K1R 6 M1 Canada
| | - B. Shea
- Bruyère Research Institute, Bruyère Continuing Care, 304b-85 Primrose Avenue, Ottawa, Ontario K1R 6 M1 Canada
- University of Ottawa, Ontario, Canada
| | - T. Rader
- Canadian Agency for Drugs and Technology in Health, 865 Carling Ave, Ottawa, Ontario Canada
| | - V. Runnels
- Globalization and Health Equity Research Unit, School of Epidemiology, Public Health and Preventive Medicine, University of Ottawa, 850 Peter Morand Crescent, Ottawa, Ontario K1G 5Z3 Canada
| | - S. Tudiver
- Gender and Health Consultant, 161 Northwestern Avenue, Ottawa, Ontario K1Y 0 M1 Canada
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Azevedo ER, Mak S, Floras JS, Parker JD. Acute effects of angiotensin-converting enzyme inhibition versus angiotensin II receptor blockade on cardiac sympathetic activity in patients with heart failure. Am J Physiol Regul Integr Comp Physiol 2017; 313:R410-R417. [PMID: 28679681 DOI: 10.1152/ajpregu.00095.2017] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2017] [Revised: 06/12/2017] [Accepted: 06/30/2017] [Indexed: 01/17/2023]
Abstract
The beneficial effects of angiotensin-converting enzyme (ACE) inhibitors and angiotensin II (ANG II) receptor antagonists in patients with heart failure secondary to reduced ejection fraction (HFrEF) are felt to result from prevention of the adverse effects of ANG II on systemic afterload and renal homeostasis. However, ANG II can activate the sympathetic nervous system, and part of the beneficial effects of ACE inhibitors and ANG II antagonists may result from their ability to inhibit such activation. We examined the acute effects of the ACE inhibitor captopril (25 mg, n = 9) and the ANG II receptor antagonist losartan (50 mg, n = 10) on hemodynamics as well as total body and cardiac norepinephrine spillover in patients with chronic HFrEF. Hemodynamic and neurochemical measurements were made at baseline and at 1, 2, and 4 h after oral dosing. Administration of both drugs caused significant reductions in systemic arterial, cardiac filling, and pulmonary artery pressures (P < 0.05 vs. baseline). There was no significant difference in the magnitude of those hemodynamic effects. Plasma concentrations of ANG II were significantly decreased by captopril and increased by losartan (P < 0.05 vs. baseline for both). Total body sympathetic activity increased in response to both captopril and losartan (P < 0.05 vs. baseline for both); however, there was no change in cardiac sympathetic activity in response to either drug. The results of the present study do not support the hypothesis that the acute inhibition of the renin-angiotensin system has sympathoinhibitory effects in patients with chronic HFrEF.
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Affiliation(s)
- Eduardo R Azevedo
- Division of Cardiology, Department of Medicine, Mount Sinai Hospital, Toronto, Ontario, Canada; Lunenfeld-Tanenbaum Research Institute, University of Toronto, Toronto, Ontario, Canada; and Department of Pharmacology and Toxicology, University of Toronto, Toronto, Ontario, Canada
| | - Susanna Mak
- Division of Cardiology, Department of Medicine, Mount Sinai Hospital, Toronto, Ontario, Canada; Lunenfeld-Tanenbaum Research Institute, University of Toronto, Toronto, Ontario, Canada; and Department of Pharmacology and Toxicology, University of Toronto, Toronto, Ontario, Canada
| | - John S Floras
- Division of Cardiology, Department of Medicine, Mount Sinai Hospital, Toronto, Ontario, Canada; Lunenfeld-Tanenbaum Research Institute, University of Toronto, Toronto, Ontario, Canada; and Department of Pharmacology and Toxicology, University of Toronto, Toronto, Ontario, Canada
| | - John D Parker
- Division of Cardiology, Department of Medicine, Mount Sinai Hospital, Toronto, Ontario, Canada; Lunenfeld-Tanenbaum Research Institute, University of Toronto, Toronto, Ontario, Canada; and Department of Pharmacology and Toxicology, University of Toronto, Toronto, Ontario, Canada
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15
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Central nervous system circuits modified in heart failure: pathophysiology and therapeutic implications. Heart Fail Rev 2015; 19:759-79. [PMID: 24573960 DOI: 10.1007/s10741-014-9427-x] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
The pathophysiology of heart failure (HF) is characterized by an abnormal activation of neurohumoral systems, including the sympathetic nervous and the renin-angiotensin-aldosterone systems, which have long-term deleterious effects on the disease progression. Perpetuation of this neurohumoral activation is partially dependent of central nervous system (CNS) pathways, mainly involving the paraventricular nucleus of the hypothalamus and some regions of the brainstem. Modifications in these integrative CNS circuits result in the attenuation of sympathoinhibitory and exacerbation of sympathoexcitatory pathways. In addition to the regulation of sympathetic outflow, these central pathways coordinate a complex network of agents with an established pathophysiological relevance in HF such as angiotensin, aldosterone, and proinflammatory cytokines. Central pathways could be potential targets in HF therapy since the current mainstay of HF pharmacotherapy aims primarily at antagonizing the peripheral mechanisms. Thus, in the present review, we describe the role of CNS pathways in HF pathophysiology and as potential novel therapeutic targets.
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16
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Floras JS, Ponikowski P. The sympathetic/parasympathetic imbalance in heart failure with reduced ejection fraction. Eur Heart J 2015; 36:1974-82b. [PMID: 25975657 DOI: 10.1093/eurheartj/ehv087] [Citation(s) in RCA: 174] [Impact Index Per Article: 19.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/29/2015] [Accepted: 03/06/2015] [Indexed: 12/20/2022] Open
Abstract
Cardiovascular autonomic imbalance, a cardinal phenotype of human heart failure, has adverse implications for symptoms during wakefulness and sleep; for cardiac, renal, and immune function; for exercise capacity; and for lifespan and mode of death. The objectives of this Clinical Review are to summarize current knowledge concerning mechanisms for disturbed parasympathetic and sympathetic circulatory control in heart failure with reduced ejection fraction and its clinical and prognostic implications; to demonstrate the patient-specific nature of abnormalities underlying this common phenotype; and to illustrate how such variation provides opportunities to improve or restore normal sympathetic/parasympathetic balance through personalized drug or device therapy.
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Affiliation(s)
- John S Floras
- University Health Network and Mount Sinai Hospital Division of Cardiology, University of Toronto, Suite 1614, 600 University Avenue, Toronto, Ontario, Canada M5G 1X5
| | - Piotr Ponikowski
- Department for Heart Disease, Medical University, Clinical Military Hospital, Wroclaw, Poland
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Booth LC, Schlaich MP, Nishi EE, Yao ST, Xu J, Ramchandra R, Lambert GW, May CN. Short-term effects of catheter-based renal denervation on cardiac sympathetic drive and cardiac baroreflex function in heart failure. Int J Cardiol 2015; 190:220-6. [PMID: 25920032 DOI: 10.1016/j.ijcard.2015.03.440] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/29/2014] [Revised: 01/08/2015] [Accepted: 03/16/2015] [Indexed: 01/18/2023]
Abstract
OBJECTIVES Sympathetic drive, especially to the heart, is elevated in heart failure and is strongly associated with poor outcome. The mechanisms causing the increased sympathetic drive to the heart remain poorly understood. Catheter-based renal denervation (RDN), which reduces blood pressure (BP) and sympathetic drive in hypertensive patients, is a potential treatment in heart failure. The aim of this study was to investigate the short-term effects of catheter-based RDN on BP, heart rate (HR) and cardiac sympathetic nerve activity (CSNA) and on baroreflex function in a conscious, large animal model of heart failure. METHODS Adult Merino ewes were paced into heart failure (ejection fraction<40%) and then instrumented to directly record CSNA. The resting levels and baroreflex control of CSNA and HR were measured before and 24h after bilateral renal (n=6) or sham (n=6) denervation. RDN was performed using the Symplicity Flex Catheter System® (Medtronic) using the same algorithm as in patients. RESULTS Catheter-based RDN significantly reduced resting diastolic BP (P<0.01) and mean arterial blood pressure (P<0.05), but did not change resting HR or CSNA compared with sham denervation. Renal denervation reduced the BP at which CSNA was at 50% of maximum (BP50; P<0.005) compared with sham denervation. CONCLUSIONS In an ovine model of heart failure, catheter-based RDN did not reduce resting CSNA in the short-term. There was, however, a lack of a reflex increase in CSNA in response to the fall in arterial pressure due to a leftward shift in the baroreflex control of CSNA, which may be due to denervation of renal efferent and/or afferent nerves.
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Affiliation(s)
- Lindsea C Booth
- Florey Institute of Neuroscience and Mental Health, Melbourne, Australia.
| | | | - Erika E Nishi
- Florey Institute of Neuroscience and Mental Health, Melbourne, Australia; Department of Physiology, Cardiovascular Division, Federal University of São Paulo, São Paulo, Brazil
| | - Song T Yao
- Florey Institute of Neuroscience and Mental Health, Melbourne, Australia
| | - Jianzhong Xu
- Baker IDI Heart and Diabetes Institute, Melbourne, Australia; Shanghai Institute of Hypertension, Ruijin Hospital, Shanghai, China
| | - Rohit Ramchandra
- Florey Institute of Neuroscience and Mental Health, Melbourne, Australia; Department of Physiology, University of Auckland, Auckland, New Zealand
| | - Gavin W Lambert
- Baker IDI Heart and Diabetes Institute, Melbourne, Australia
| | - Clive N May
- Florey Institute of Neuroscience and Mental Health, Melbourne, Australia
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Feber J, Ruzicka M, Geier P, Litwin M. Autonomic nervous system dysregulation in pediatric hypertension. Curr Hypertens Rep 2014; 16:426. [PMID: 24633841 DOI: 10.1007/s11906-014-0426-z] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
Historically, primary hypertension (HTN) has been prevalent typically in adults. Recent data however, suggests an increasing number of children diagnosed with primary HTN, mainly in the setting of obesity. One of the factors considered in the etiology of HTN is the autonomous nervous system, namely its dysregulation. In the past, the sympathetic nervous system (SNS) was regarded as a system engaged mostly in buffering major acute changes in blood pressure (BP), in response to physical and emotional stressors. Recent evidence suggests that the SNS plays a much broader role in the regulation of BP, including the development and maintenance of sustained HTN by a chronically elevated central sympathetic tone in adults and children with central/visceral obesity. Consequently, attempts have been made to reduce the SNS hyperactivity, in order to intervene early in the course of the disease and prevent HTN-related complications later in life.
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Affiliation(s)
- Janusz Feber
- Division of Nephrology, Department of Pediatrics, Children's Hospital of Eastern Ontario, University of Ottawa, 401 Smyth Road, Ottawa, Ontario, K1H 8 L1, Canada,
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19
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Leenen FHH. Actions of circulating angiotensin II and aldosterone in the brain contributing to hypertension. Am J Hypertens 2014; 27:1024-32. [PMID: 24742639 DOI: 10.1093/ajh/hpu066] [Citation(s) in RCA: 46] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023] Open
Abstract
In the past 1-2 decades, it has become apparent that the brain renin-angiotensin-aldosterone system (RAAS) plays a crucial role in the regulation of blood pressure (BP) by the circulating RAAS. In the brain, angiotensinergic sympatho-excitatory pathways do not contribute to acute, second-to-second regulation but play a major role in the more chronic regulation of the setpoint for sympathetic tone and BP. Increases in plasma angiotensin II (Ang II) or aldosterone and in cerebrospinal fluid [Na(+)] can directly activate these pathways and chronically further activate/maintain enhanced activity by a slow neuromodulatory pathway involving local aldosterone, mineralocorticoid receptors (MRs), epithelial sodium channels, and endogenous ouabain. Blockade of any step in this slow pathway prevents Ang II-, aldosterone-, or salt and renal injury-induced forms of hypertension. It appears that the renal and arterial actions of circulating aldosterone and Ang II act as amplifiers but are not sufficient to cause chronic hypertension if their central actions are prevented, except perhaps at high concentrations. From a clinical perspective, oral treatment with an angiotensin type 1 (AT1)-receptor blocker at high doses can cause central AT1-receptor blockade and, in humans, lower sympathetic nerve activity. Low doses of the MR blocker spironolactone appear sufficient to cause central MR blockade and a decrease in sympathetic nerve activity. Integrating the brain actions of the circulating RAAS with its direct renal and arterial actions provides a better framework to understand the role of the circulating RAAS in the pathophysiology of hypertension and heart failure and to direct therapeutic strategies.
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Affiliation(s)
- Frans H H Leenen
- Hypertension Unit, University of Ottawa Heart Institute, Ottawa, Ontario, Canada.
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20
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Silva JA, Santana ET, Manchini MT, Antônio EL, Bocalini DS, Krieger JE, Tucci PJF, Serra AJ. Exercise training can prevent cardiac hypertrophy induced by sympathetic hyperactivity with modulation of kallikrein-kinin pathway and angiogenesis. PLoS One 2014; 9:e91017. [PMID: 24614810 PMCID: PMC3948752 DOI: 10.1371/journal.pone.0091017] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2013] [Accepted: 02/07/2014] [Indexed: 01/19/2023] Open
Abstract
Sympathetic hyperactivity induces adverse effects in myocardial. Recent studies have shown that exercise training induces cardioprotection against sympathetic overload; however, relevant mechanisms of this issue remain unclear. We analyzed whether exercise can prevent pathological hypertrophy induced by sympathetic hyperactivity with modulation of the kallikrein-kinin and angiogenesis pathways. Male Wistar rats were assigned to non-trained group that received vehicle; non-trained isoproterenol treated group (Iso, 0.3 mg kg(-1) day-(1)); and trained group (Iso+Exe) which was subjected to sympathetic hyperactivity with isoproterenol. The Iso rats showed hypertrophy and myocardial dysfunction with reduced force development and relaxation of muscle. The isoproterenol induced severe fibrosis, apoptosis and reduced myocardial capillary. Interestingly, exercise blunted hypertrophy, myocardial dysfunction, fibrosis, apoptosis and capillary decreases. The sympathetic hyperactivity was associated with high abundance of ANF mRNA and β-MHC mRNA, which was significantly attenuated by exercise. The tissue kallikrein was augmented in the Iso+Exe group, and kinin B1 receptor mRNA was increased in the Iso group. Moreover, exercise induced an increase of kinin B2 receptor mRNA in myocardial. The myocardial content of eNOS, VEGF, VEGF receptor 2, pAkt and Bcl-2 were increased in the Iso+Exe group. Likewise, increased expression of pro-apoptotic Bad in the Iso rats was prevented by prior exercise. Our results represent the first demonstration that exercise can modulate kallikrein-kinin and angiogenesis pathways in the myocardial on sympathetic hyperactivity. These findings suggest that kallikrein-kinin and angiogenesis may have a key role in protecting the heart.
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Affiliation(s)
- José Antônio Silva
- Universidade Nove de Julho (Uninove), Programa de Pós-graduação em Ciências da Reabilitação, Rua Vergueiro, São Paulo, SP, Brazil
- Universidade Nove de Julho (Uninove), Programa de Pós-graduação em Medicina, Rua Vergueiro, São Paulo, SP, Brazil
| | - Eduardo Tadeu Santana
- Universidade Nove de Julho (Uninove), Programa de Pós-graduação em Ciências da Reabilitação, Rua Vergueiro, São Paulo, SP, Brazil
| | - Martha Trindade Manchini
- Universidade Nove de Julho (Uninove), Programa de Pós-graduação em Ciências da Reabilitação, Rua Vergueiro, São Paulo, SP, Brazil
| | - Ednei Luis Antônio
- Universidade Federal de São Paulo (Unifesp), Rua Napoleão de Barros, São Paulo, SP, Brazil
| | - Danilo Sales Bocalini
- Universidade Nove de Julho (Uninove), Programa de Pós-graduação em Ciências da Reabilitação, Rua Vergueiro, São Paulo, SP, Brazil
| | - José Eduardo Krieger
- Universidade de São Paulo, Incor. Av. Dr. Enéas de Carvalho Aguiar, São Paulo, SP, Brazil
| | | | - Andrey Jorge Serra
- Universidade Nove de Julho (Uninove), Programa de Pós-graduação em Ciências da Reabilitação, Rua Vergueiro, São Paulo, SP, Brazil
- Universidade Nove de Julho (Uninove), Programa de Pós-graduação em Medicina, Rua Vergueiro, São Paulo, SP, Brazil
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Abstract
OBJECTIVES Clinical outcomes are worse for patients with heart failure (HF) and elevated depression symptoms. Depression-related sympathoimmune dysregulation may be one mechanism leading to poorer HF prognosis. Sympathetically mediated adrenergic activity is known to regulate immune activity via β-adrenergic receptors (β-ARs). However, studies show conflicting relationships between leukocyte β-AR sensitivity and depression symptoms. The aim of this study was to determine in patients with HF the relationship of leukocyte β-AR sensitivity with two diverse measures of depression, self-report questionnaire versus clinical diagnostic interview. METHODS Patients with HF (N = 73, mean [standard deviation] age = 56.3 [13.0]) completed the Beck Depression Inventory-1A and a modified Structured Clinical Interview for the DSM-IV. Leukocyte β-AR sensitivity was determined from isoproterenol-stimulated cyclic adenosine monophosphate levels; plasma norepinephrine and epinephrine were also assessed. RESULTS Patients with major depression determined by Structured Clinical Interview for the DSM-IV had significantly higher β-AR sensitivity than did nondepressed patients (F(6,72) = 9.27, p = .003, η = 0.12). The Beck Depression Inventory-1A revealed a more complex relationship. Minimal, mild, and moderate-to-severe depression symptom groups had significant differences in β-AR sensitivity (F(7,72) = 7.03, p = .002, η = 0.18); mild symptoms were associated with reduced β-AR sensitivity and moderate-to-severe symptoms with higher β-AR sensitivity compared with patients with minimal depressive symptoms. CONCLUSIONS Clinical depression was associated with elevated β-AR sensitivity in patients with HF. By deconstructing depression measurements, a greater depth of information may be garnered to potentially reveal subtypes of depression symptoms and their relation to β-AR sensitivity.
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Abstract
Statins (3-hydroxy-3-methylglutaryl-CoA reductase inhibitors) reduce plasma cholesterol and improve endothelium-dependent vasodilation, inflammation and oxidative stress. A ‘pleiotropic’ property of statins receiving less attention is their effect on the autonomic nervous system. Increased central sympathetic outflow and diminished cardiac vagal tone are disturbances characteristic of a range of cardiovascular conditions for which statins are now prescribed routinely to reduce cardiovascular events: following myocardial infarction, and in hypertension, chronic kidney disease, heart failure and diabetes. The purpose of the present review is to synthesize contemporary evidence that statins can improve autonomic circulatory regulation. In experimental preparations, high-dose lipophilic statins have been shown to reduce adrenergic outflow by attenuating oxidative stress in central brain regions involved in sympathetic and parasympathetic discharge induction and modulation. In patients with hypertension, chronic kidney disease and heart failure, lipophilic statins, such as simvastatin or atorvastatin, have been shown to reduce MNSA (muscle sympathetic nerve activity) by 12–30%. Reports concerning the effect of statin therapy on HRV (heart rate variability) are less consistent. Because of their implications for BP (blood pressure) control, insulin sensitivity, arrhythmogenesis and sudden cardiac death, these autonomic nervous system actions should be considered additional mechanisms by which statins lower cardiovascular risk.
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Leenen FHH. CNS pathways contributing to sympathetic hyperactivity and hypertension. Hypertension 2013. [DOI: 10.2217/ebo.12.235] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Affiliation(s)
- Frans HH Leenen
- Frans HH Leenen is Professor of Medicine and Pharmacology at the University of Ottawa School of Medicine (ON, Canada), Director of the Hypertension Unit at the University of Ottawa Heart Institute (ON, Canada) and, since 2004, the first recipient of the Pfizer Research Chair in Hypertension, an endowed Chair supported by Pfizer Canada, the Ottawa Heart Institute Foundation and Canadian Institutes of Health Research. His current areas of research are the brain mechanisms determining sympathetic
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