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Dhyani N, Tian C, Gao L, Rudebush TL, Zucker IH. Nrf2-Keap1 in Cardiovascular Disease: Which Is the Cart and Which the Horse? Physiology (Bethesda) 2024; 39:0. [PMID: 38687468 DOI: 10.1152/physiol.00015.2024] [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: 03/11/2024] [Revised: 04/23/2024] [Accepted: 04/24/2024] [Indexed: 05/02/2024] Open
Abstract
High levels of oxidant stress in the form of reactive oxidant species are prevalent in the circulation and tissues in various types of cardiovascular disease including heart failure, hypertension, peripheral arterial disease, and stroke. Here we review the role of nuclear factor erythroid 2-related factor 2 (Nrf2), an important and widespread antioxidant and anti-inflammatory transcription factor that may contribute to the pathogenesis and maintenance of cardiovascular diseases. We review studies showing that downregulation of Nrf2 exacerbates heart failure, hypertension, and autonomic function. Finally, we discuss the potential for using Nrf2 modulation as a therapeutic strategy for cardiovascular diseases and autonomic dysfunction.
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Affiliation(s)
- Neha Dhyani
- Department of Cellular and Integrative Physiology, University of Nebraska Medical Center, Omaha, Nebraska, United States
| | - Changhai Tian
- Department of Toxicology and Cancer Biology, University of Kentucky College of Medicine, Lexington, Kentucky, United States
| | - Lie Gao
- Department of Anesthesiology, University of Nebraska Medical Center, Omaha, Nebraska, United States
| | - Tara L Rudebush
- Department of Cellular and Integrative Physiology, University of Nebraska Medical Center, Omaha, Nebraska, United States
| | - Irving H Zucker
- Department of Cellular and Integrative Physiology, University of Nebraska Medical Center, Omaha, Nebraska, United States
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Plunkett MJ, Holwerda S, Young BE, Fadel PJ, Fisher JP. Respiratory modulation of sympathetic transduction to blood pressure in health and type 2 diabetes. J Physiol 2024; 602:3909-3927. [PMID: 39073892 PMCID: PMC11326975 DOI: 10.1113/jp286627] [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: 03/25/2024] [Accepted: 07/12/2024] [Indexed: 07/31/2024] Open
Abstract
Type 2 diabetes (T2D) is often accompanied by hypertension, exaggerated blood pressure (BP) responses to sympatho-excitatory stressors, and raised cardiovascular disease risk. Appropriate respiratory-sympathetic coupling and sympathetic transduction to BP are important for short- and longer-term BP control. We tested the hypotheses that respiratory modulation of muscle sympathetic nerve activity (MSNA) and its transduction to BP would be impaired in T2D and associated with higher BP and respiratory-coupled BP variability. Resting MSNA, respiration and beat-to-beat BP were recorded in 20 T2D (49.1 ± 7.4 years; mean ± SD) and 13 healthy control (46.3 ± 9.4 years) participants. MSNA and the transduction of sympathetic bursts (signal-averaging) to mean arterial pressure (MAP) were compared at low and high lung volume phases. The peak MAP response following a sympathetic burst was lower during the high lung volume than low lung volume phase in controls (P = 0.005), whereas it was unchanged with phase in T2D participants (P = 0.522). Respiratory modulation of MSNA was impaired in T2D participants, who had an attenuated reduction in burst incidence from low to the high lung volume phase, versus controls (27.8 ± 38.4% vs. 49.4 ± 24.6%, respectively; P = 0.043). The T2D participants were grouped into unimpaired respiratory modulators (burst incidence modulation median or above) or impaired respiratory modulators (below median). Impaired modulators had higher systolic BP (133 ± 14 vs. 121 ± 11 mmHg, P = 0.046), greater Traube-Hering wave amplitudes (6.3 ± 2.4 vs. 4.6 ± 1.1 mmHg; P = 0.028) and higher BP variability (MAP average real variability, 2.0 ± 0.7 vs. 1.4 ± 0.3, P = 0.033). Respiratory modulation of MSNA and sympathetic transduction to BP are altered in T2D patients and may contribute to their increased hypertension and cardiovascular risk. KEY POINTS: Respiratory-sympathetic coupling and sympathetic transduction to blood pressure (BP) contribute to short- and longer-term BP control. Our understanding of these processes in health and type 2 diabetes (T2D), a condition with high prevalence of hypertension and cardiovascular risk, is incomplete. We found that respiration and sympathetic transduction to BP are coupled in healthy individuals. The mean arterial pressure response to a sympathetic burst was reduced during the high lung volume compared to the low lung volume phase. This coupling was absent in T2D. Respiratory modulation of muscle sympathetic nerve activity (MSNA) is impaired in T2D, with a blunted reduction of MSNA observed during the high lung volume phase. T2D patients with impaired respiratory MSNA modulation had augmented systolic BP, respiratory-related BP excursions (Traube-Hering waves) and BP variability. Abnormal respiratory modulation of MSNA and sympathetic transduction to BP in T2D may contribute to altered blood pressure control and cardiovascular risk in this population.
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Affiliation(s)
- Michael J Plunkett
- Manaaki Manawa - The Centre for Heart Research, Department of Physiology, Faculty of Medical and Health Sciences, University of Auckland, Auckland, New Zealand
| | - Seth Holwerda
- Department of Anesthesiology, University of Kansas Medical Center, Kansas City, KS, USA
| | - Benjamin E Young
- Department of Kinesiology, Health Promotion and Recreation, College of Education, The University of North Texas, Denton, TX, USA
| | - Paul J Fadel
- Department of Kinesiology, College of Nursing and Health Innovation, University of Texas at Arlington, Arlington, TX, USA
| | - James P Fisher
- Manaaki Manawa - The Centre for Heart Research, Department of Physiology, Faculty of Medical and Health Sciences, University of Auckland, Auckland, New Zealand
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Lin WL, Hsiao YW, Liu SH, Cheng WH, Tsai TY, Chou YH, Yang CCH, Kuo TBJ, Chen SA, Lo LW. Effects of low-density lipoprotein cholesterol on sleep apnea: Insights from a rat model of cardiovascular autonomic dysregulation. Sleep Med 2024; 115:76-82. [PMID: 38340526 DOI: 10.1016/j.sleep.2024.02.008] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/11/2023] [Revised: 01/20/2024] [Accepted: 02/01/2024] [Indexed: 02/12/2024]
Abstract
INTRODUCTION The levels of low-density lipoprotein (LDL) cholesterol in plasma are important risk factors for coronary heart disease. Several reports suggest that elevated plasma cholesterol is associated with cardiac arrhythmias. In a subsequent study investigating LDL cholesterol levels and the frequency of LDL cholesterol measurements, a positive correlation was observed between the severity of sleep apnea and visit-to-visit LDL cholesterol variability. Our objective was to assess the effects of hypercholesterolemia on cardiac autonomic activity, disordered sleep patterns, and increased incidence of arrhythmias in freely moving rats. METHODS Wireless transmission of polysomnographic recordings was performed in control and high cholesterol male rats during normal daytime sleep. Spectral analyses were conducted on the electroencephalogram and electromyogram (EMG) recordings to distinguish active waking, quiet sleep, and paradoxical sleep. Heart rate variability power spectrum analysis was used to measure cardiac autonomic activity. RESULTS The high cholesterol group exhibited a higher low-frequency (LF)/high-frequency (HF) power ratio during all sleep stages compared to the control group. Additionally, the frequency of sleep interruptions was increased in the high cholesterol group compared to the control group. CONCLUSIONS Our results show significant sleep fragmentation with sympathetic hyperactivity after exposure to high cholesterol. This indicates that high cholesterol may increase the risk of sleep apnea and poor sleep quality by disrupting autonomic homeostasis.
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Affiliation(s)
- Wei-Lun Lin
- Heart Rhythm Center, Division of Cardiology, Department of Internal Medicine, Taipei Veterans General Hospital, Taipei, Taiwan; Institute of Clinical Medicine, National Yang Ming Chiou Tung University, Taipei, Taiwan; Department of Medical Research, Taichung Veterans General Hospital, Taichung, Taiwan; Cardiovascular Center, Taichung Veterans General Hospital, Taichung, Taiwan; Institute of Biomedical Sciences, MacKay Medical College, New Taipei City, Taiwan
| | - Ya-Wen Hsiao
- Heart Rhythm Center, Division of Cardiology, Department of Internal Medicine, Taipei Veterans General Hospital, Taipei, Taiwan
| | - Shin-Huei Liu
- Heart Rhythm Center, Division of Cardiology, Department of Internal Medicine, Taipei Veterans General Hospital, Taipei, Taiwan; Institute of Clinical Medicine, National Yang Ming Chiou Tung University, Taipei, Taiwan
| | - Wen-Han Cheng
- Heart Rhythm Center, Division of Cardiology, Department of Internal Medicine, Taipei Veterans General Hospital, Taipei, Taiwan; Institute of Clinical Medicine, National Yang Ming Chiou Tung University, Taipei, Taiwan
| | - Tsung-Ying Tsai
- Cardiovascular Center, Taichung Veterans General Hospital, Taichung, Taiwan
| | - Yu-Hui Chou
- Heart Rhythm Center, Division of Cardiology, Department of Internal Medicine, Taipei Veterans General Hospital, Taipei, Taiwan
| | - Cheryl C H Yang
- Institute of Brain Science, National Yang Ming Chiou Tung University, Taipei, Taiwan; Sleep Research Center, National Yang Ming Chiou Tung University, Taipei, Taiwan; Taoyuan Psychiatric Center, Taoyuan Psychiatric Hospital, Taoyuan, Taiwan
| | - Terry B J Kuo
- Institute of Brain Science, National Yang Ming Chiou Tung University, Taipei, Taiwan
| | - Shih-Ann Chen
- Heart Rhythm Center, Division of Cardiology, Department of Internal Medicine, Taipei Veterans General Hospital, Taipei, Taiwan; Institute of Clinical Medicine, National Yang Ming Chiou Tung University, Taipei, Taiwan; Cardiovascular Center, Taichung Veterans General Hospital, Taichung, Taiwan; Department of Post Baccalaureate Medicine, College of Medicine, National Chung Hsing University, Taichung, Taiwan
| | - Li-Wei Lo
- Heart Rhythm Center, Division of Cardiology, Department of Internal Medicine, Taipei Veterans General Hospital, Taipei, Taiwan; Institute of Clinical Medicine, National Yang Ming Chiou Tung University, Taipei, Taiwan.
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Bunsawat K, Skow RJ, Kaur J, Wray DW. Neural control of the circulation during exercise in heart failure with reduced and preserved ejection fraction. Am J Physiol Heart Circ Physiol 2023; 325:H998-H1011. [PMID: 37682236 PMCID: PMC10907034 DOI: 10.1152/ajpheart.00214.2023] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/17/2023] [Revised: 08/23/2023] [Accepted: 09/06/2023] [Indexed: 09/09/2023]
Abstract
Patients with heart failure with reduced (HFrEF) and preserved ejection fraction (HFpEF) exhibit severe exercise intolerance that may be due, in part, to inappropriate cardiovascular and hemodynamic adjustments to exercise. Several neural mechanisms and locally released vasoactive substances work in concert through complex interactions to ensure proper adjustments to meet the metabolic demands of the contracting skeletal muscle. Specifically, accumulating evidence suggests that disease-related alterations in neural mechanisms (e.g., central command, exercise pressor reflex, arterial baroreflex, and cardiopulmonary baroreflex) contribute to heightened sympathetic activation and impaired ability to attenuate sympathetic vasoconstrictor responsiveness that may contribute to reduced skeletal muscle blood flow and severe exercise intolerance in patients with HFrEF. In contrast, little is known regarding these important aspects of physiology in patients with HFpEF, though emerging data reveal heightened sympathetic activation and attenuated skeletal muscle blood flow during exercise in this patient population that may be attributable to dysregulated neural control of the circulation. The overall goal of this review is to provide a brief overview of the current understanding of disease-related alterations in the integrative neural cardiovascular responses to exercise in both HFrEF and HFpEF phenotypes, with a focus on sympathetic nervous system regulation during exercise.
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Affiliation(s)
- Kanokwan Bunsawat
- Division of Geriatrics, Department of Internal Medicine, University of Utah, Salt Lake City, Utah, United States
- Geriatric Research, Education, and Clinical Center, George E. Wahlen Department of Veterans Affairs Medical Center, Salt Lake City, Utah, United States
| | - Rachel J Skow
- Department of Kinesiology, The University of Texas at Arlington, Arlington, Texas, United States
- Faculty of Nursing, University of Alberta, Edmonton, Alberta, Canada
| | - Jasdeep Kaur
- Department of Kinesiology and Health Education, The University of Texas at Austin, Austin, Texas, United States
| | - D Walter Wray
- Division of Geriatrics, Department of Internal Medicine, University of Utah, Salt Lake City, Utah, United States
- Geriatric Research, Education, and Clinical Center, George E. Wahlen Department of Veterans Affairs Medical Center, Salt Lake City, Utah, United States
- Department of Nutrition and Integrative Physiology, University of Utah, Salt Lake City, Utah, United States
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Jia S, Lu W, Hang M, Zhang C, Ma Z, Xue K, Lu Y, Zhang S, Guo Y, Zhang J, Zhang X, Wang Y, Zhao H. Study on the effect of acupunture treatment on autonomic nerve dysfunction in convalescent period of stroke based on heart rate variability assessment technique. Medicine (Baltimore) 2022; 101:e32355. [PMID: 36550889 PMCID: PMC9771218 DOI: 10.1097/md.0000000000032355] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
Stroke patients with autonomic dysfunction are more likely to develop cardiac problems, which have been linked to lower functional outcomes and increased mortality. In this study, heart rate variability (HRV) detection paired with the Clinical Feature Scale will be utilized to elucidate the immediate impact of manual acupuncture on autonomic dysfunction of varying severity in the convalescence stroke phase. This is a randomized, single-blind, controlled clinical trial approach. At a ratio of 1:1, 60 appropriate patients will be randomly randomized into either the experimental or control group. On the basis of symptomatic treatment drugs, the experimental group will additionally undertake acupuncture therapy 3 times a week for 4 weeks, for a total of 12 times. Primary outcomes include 24-hour HRV and 60-minute HRV detection at week 4 compared with baseline. The secondary outcome is the score of clinical feature scale at week 4 compared with the baseline. Adverse events and safety indices will be recorded throughout the experiment. The SPSS V.25.0 statistical program was applied for analysis, and measurement data were expressed as mean ± SD.
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Affiliation(s)
- Shijing Jia
- Longhua Hospital, Shanghai University of Traditional Chinese Medicine, Shanghai, China
- Shanghai University of Traditional Chinese Medicine, Shanghai, China
| | - Wang Lu
- Longhua Hospital, Shanghai University of Traditional Chinese Medicine, Shanghai, China
- Shanghai University of Traditional Chinese Medicine, Shanghai, China
- * Correspondence: Wang Lu, Longhua Hospital, Shanghai University of Traditional Chinese Medicine, 725 South Wanping Road, Shanghai, China (e-mail: )
| | - Minghui Hang
- Longhua Hospital, Shanghai University of Traditional Chinese Medicine, Shanghai, China
- Shanghai University of Traditional Chinese Medicine, Shanghai, China
| | - Chu Zhang
- Longhua Hospital, Shanghai University of Traditional Chinese Medicine, Shanghai, China
- Shanghai University of Traditional Chinese Medicine, Shanghai, China
| | - Zilin Ma
- Longhua Hospital, Shanghai University of Traditional Chinese Medicine, Shanghai, China
| | - Kun Xue
- Shanghai Changning Tianshan Traditional Chinese Medicine Hospital, Shanghai, China
| | - Yunqi Lu
- Shanghai Fifth People’s Hospital, Shanghai, China
| | - Shenghong Zhang
- Longhua Hospital, Shanghai University of Traditional Chinese Medicine, Shanghai, China
| | - Yijin Guo
- Longhua Hospital, Shanghai University of Traditional Chinese Medicine, Shanghai, China
| | - Jiabao Zhang
- Longhua Hospital, Shanghai University of Traditional Chinese Medicine, Shanghai, China
| | - Xinyu Zhang
- Longhua Hospital, Shanghai University of Traditional Chinese Medicine, Shanghai, China
| | - Yimeng Wang
- Longhua Hospital, Shanghai University of Traditional Chinese Medicine, Shanghai, China
| | - Haiyin Zhao
- Longhua Hospital, Shanghai University of Traditional Chinese Medicine, Shanghai, China
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Statins: Neurobiological underpinnings and mechanisms in mood disorders. Neurosci Biobehav Rev 2021; 128:693-708. [PMID: 34265321 DOI: 10.1016/j.neubiorev.2021.07.012] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2020] [Revised: 06/28/2021] [Accepted: 07/10/2021] [Indexed: 12/26/2022]
Abstract
Statins (3-hydroxy-3-methylglutaryl-coenzyme A reductase inhibitors) treat dyslipidaemia and cardiovascular disease by inhibiting cholesterol biosynthesis. They also have immunomodulatory and anti-inflammatory properties. Beyond cardiovascular disease, cholesterol and inflammation appear to be components of the pathogenesis and pathophysiology of neuropsychiatric disorders. Statins may therefore afford some therapeutic benefit in mood disorders. In this paper, we review the pathophysiology of mood disorders with a focus on pharmacologically relevant pathways, using major depressive disorder and bipolar disorder as exemplars. Statins are discussed in the context of these disorders, with particular focus on the putative mechanisms involved in their anti-inflammatory and immunomodulatory effects. Recent clinical data suggest that statins may have antidepressant properties, however given their interactions with many known biological pathways, it has not been fully elucidated which of these are the major determinants of clinical outcomes in mood disorders. Moreover, it remains unclear what the appropriate dose, or appropriate patient phenotype for adjunctive treatment may be. High quality randomised control trials in concert with complementary biological investigations are needed if the potential clinical effects of statins on mood disorders, as well as their biological correlates, are to be better understood.
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Effects of Statins on Renin-Angiotensin System. J Cardiovasc Dev Dis 2021; 8:jcdd8070080. [PMID: 34357323 PMCID: PMC8305238 DOI: 10.3390/jcdd8070080] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2021] [Revised: 07/02/2021] [Accepted: 07/05/2021] [Indexed: 12/16/2022] Open
Abstract
Statins, a class of drugs for lowering serum LDL-cholesterol, have attracted attention because of their wide range of pleiotropic effects. An important but often neglected effect of statins is their role in the renin–angiotensin system (RAS) pathway. This pathway plays an integral role in the progression of several diseases including hypertension, heart failure, and renal disease. In this paper, the role of statins in the blockade of different components of this pathway and the underlying mechanisms are reviewed and new therapeutic possibilities of statins are suggested.
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8
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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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Prasad B, Morgan BJ, Gupta A, Pegelow DF, Teodorescu M, Dopp JM, Dempsey JA. The need for specificity in quantifying neurocirculatory vs. respiratory effects of eucapnic hypoxia and transient hyperoxia. J Physiol 2020; 598:4803-4819. [PMID: 32770545 DOI: 10.1113/jp280515] [Citation(s) in RCA: 28] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2020] [Accepted: 08/04/2020] [Indexed: 12/24/2022] Open
Abstract
KEY POINTS The carotid chemoreceptor mediates the ventilatory and muscle sympathetic nerve activity (MSNA) responses to hypoxia and contributes to tonic sympathetic and respiratory drives. It is often presumed that both excitatory and inhibitory tests of chemoreflex function show congruence in the end-organ responses. Ventilatory and neurocirculatory (MSNA, blood pressure and heart rate) responses to chemoreflex inhibition elicited by transient hyperoxia and to chemoreflex excitation produced by steady-state eucapnic hypoxia were measured in a cohort of 82 middle-aged individuals. Ventilatory and MSNA responsiveness to hyperoxia and hypoxia were not significantly correlated within individuals. It was concluded that ventilatory responses to hypoxia and hyperoxia do not predict MSNA responses and it is recommended that tests using the specific outcome of interest, i.e. MSNA or ventilation, are required. Transient hyperoxia is recommended as a sensitive and reliable means of quantifying tonic chemoreceptor-driven levels of sympathetic nervous system activity and respiratory drive. ABSTRACT Hypersensitivity of the carotid chemoreceptor leading to sympathetic nervous system activation and ventilatory instability has been implicated in the pathogenesis and consequences of several common clinical conditions. A variety of treatment approaches aimed at lessening chemoreceptor-driven sympathetic overactivity are now under investigation; thus, the ability to quantify this outcome variable with specificity and precision is crucial. Accordingly, we measured ventilatory and neurocirculatory responses to chemoreflex inhibition elicited by transient hyperoxia and chemoreflex excitation produced by exposure to graded, steady-state eucapnic hypoxia in middle-aged men and women (n = 82) with continuous positive airway pressure-treated obstructive sleep apnoea. Progressive, eucapnic hypoxia produced robust and highly variable increases in ventilation (+83 ± 59%) and muscle sympathetic nerve activity (MSNA) burst frequency (+55 ± 31%), whereas transient hyperoxia caused marked reductions in these variables (-35 ± 14% and -42 ± 16%, respectively). Coefficients of variation for ventilatory and MSNA burst frequency responses, indicating test-retest reproducibility, were respectively 9% and 24% for hyperoxia and 35% and 28% for hypoxia. Based on statistical measures of rank correlation or even comparisons across quartiles of corresponding ventilatory and MSNA responses, we found that the magnitudes of ventilatory inhibition with hyperoxia or excitation with eucapnic hypoxia were not correlated with corresponding MSNA responses within individuals. We conclude that, in conscious, behaving humans, ventilatory sensitivities to progressive, steady-state, eucapnic hypoxia and transient hyperoxia do not predict MSNA responsiveness. Our findings also support the use of transient hyperoxia as a reliable, sensitive, measure of the carotid chemoreceptor contribution to tonic sympathetic nervous system activity and respiratory drive.
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Affiliation(s)
- Bharati Prasad
- Department of Medicine, University of Illinois at Chicago, Chicago, IL, USA
| | - Barbara J Morgan
- John Rankin Laboratory of Pulmonary Medicine, School of Medicine and Public Health, University of Wisconsin-Madison, Madison, WI, USA.,Department of Orthopedics and Rehabilitation, School of Medicine and Public Health, University of Wisconsin-Madison, Madison, WI, USA
| | - Ahana Gupta
- GPPA Medical Scholars Program, University of Illinois at Chicago, Chicago, IL, USA
| | - David F Pegelow
- Department of Pediatrics, School of Medicine and Public Health, University of Wisconsin-Madison, Madison, WI, USA
| | - Mihaela Teodorescu
- Department of Medicine, School of Medicine and Public Health, University of Wisconsin-Madison, Madison, WI, USA
| | - John M Dopp
- Pharmacy Practice Division, School of Pharmacy, University of Wisconsin-Madison, Madison, WI, USA
| | - Jerome A Dempsey
- John Rankin Laboratory of Pulmonary Medicine, School of Medicine and Public Health, University of Wisconsin-Madison, Madison, WI, USA.,Department of Population Health Sciences, School of Medicine and Public Health, University of Wisconsin-Madison, WI, USA
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10
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Bunsawat K, Ratchford SM, Alpenglow JK, Park SH, Jarrett CL, Stehlik J, Drakos SG, Richardson RS, Wray DW. Chronic antioxidant administration restores macrovascular function in patients with heart failure with reduced ejection fraction. Exp Physiol 2020; 105:1384-1395. [PMID: 32495411 DOI: 10.1113/ep088686] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2020] [Accepted: 06/02/2020] [Indexed: 12/26/2022]
Abstract
NEW FINDINGS What is the central question of this study? We aimed to examine oxidative stress, antioxidant capacity and macro- and microvascular function in response to 30 days of oral antioxidant administration in patients with heart failure with reduced ejection fraction. What is the main finding and its importance? We observed an approximately twofold improvement in macrovascular function, assessed via brachial artery flow-mediated dilatation, and a reduction in oxidative stress after antioxidant administration in patients with heart failure with reduced ejection fraction. The improvement in macrovascular function was reversed 1 week after treatment cessation. These findings have identified the potential of oral antioxidant administration to optimize macrovascular health in this patient group. ABSTRACT Heart failure with reduced ejection fraction (HFrEF) is characterized by macrovascular dysfunction and elevated oxidative stress that may be mitigated by antioxidant (AOx) administration. In this prospective study, we assessed flow-mediated dilatation (FMD) and reactive hyperaemia responses in 14 healthy, older control participants and 14 patients with HFrEF, followed by 30 days of oral AOx administration (1 g vitamin C, 600 I.U. vitamin E and 0.6 g α-lipoic acid) in the patient group. Blood biomarkers of oxidative stress (malondialdehyde) and AOx capacity (ferric reducing ability of plasma) were also assessed. Patients with HFrEF had a lower %FMD (2.63 ± 1.57%) than control participants (5.62 ± 2.60%), and AOx administration improved %FMD in patients with HFrEF (30 days, 4.90 ± 2.38%), effectively restoring macrovascular function to that of control participants. In a subset of patients, we observed a progressive improvement in %FMD across the treatment period (2.62 ± 1.62, 4.23 ± 2.69, 4.33 ± 2.24 and 4.97 ± 2.56% at days 0, 10, 20 and 30, respectively, n = 12) that was abolished 7 days after treatment cessation (2.99 ± 1.78%, n = 9). No difference in reactive hyperaemia was evident between groups or as a consequence of the AOx treatment. Ferric reducing ability of plasma levels increased (from 6.08 ± 2.80 to 6.70 ± 1.59 mm, day 0 versus 30) and malondialdehyde levels decreased (from 6.81 ± 2.80 to 6.22 ± 2.84 μm, day 0 versus 30) after treatment. These findings demonstrate the efficacy of chronic AOx administration in attenuating oxidative stress, improving AOx capacity and restoring macrovascular function in patients with HFrEF.
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Affiliation(s)
- Kanokwan Bunsawat
- Department of Internal Medicine, Division of Geriatrics, University of Utah, Salt Lake City, UT, USA
| | - Stephen M Ratchford
- Department of Internal Medicine, Division of Geriatrics, University of Utah, Salt Lake City, UT, USA.,Geriatric Research, Education, and Clinical Center, George E. Wahlen Department of Veterans Affairs Medical Center, Salt Lake City, UT, USA.,Department of Health & Exercise Science, Appalachian State University, Boone, NC, USA
| | - Jeremy K Alpenglow
- Department of Nutrition and Integrative Physiology, University of Utah, Salt Lake City, UT, USA
| | - Soung Hun Park
- Department of Nutrition and Integrative Physiology, University of Utah, Salt Lake City, UT, USA
| | - Catherine L Jarrett
- Department of Internal Medicine, Division of Geriatrics, University of Utah, Salt Lake City, UT, USA.,Geriatric Research, Education, and Clinical Center, George E. Wahlen Department of Veterans Affairs Medical Center, Salt Lake City, UT, USA
| | - Josef Stehlik
- Department of Internal Medicine, Division of Cardiovascular Medicine, University of Utah, Salt Lake City, UT, USA
| | - Stavros G Drakos
- Department of Internal Medicine, Division of Cardiovascular Medicine, University of Utah, Salt Lake City, UT, USA
| | - Russell S Richardson
- Department of Internal Medicine, Division of Geriatrics, University of Utah, Salt Lake City, UT, USA.,Geriatric Research, Education, and Clinical Center, George E. Wahlen Department of Veterans Affairs Medical Center, Salt Lake City, UT, USA.,Department of Nutrition and Integrative Physiology, University of Utah, Salt Lake City, UT, USA
| | - D Walter Wray
- Department of Internal Medicine, Division of Geriatrics, University of Utah, Salt Lake City, UT, USA.,Geriatric Research, Education, and Clinical Center, George E. Wahlen Department of Veterans Affairs Medical Center, Salt Lake City, UT, USA.,Department of Nutrition and Integrative Physiology, University of Utah, Salt Lake City, UT, USA
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11
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The Role of Oxidative Stress in Cardiac Disease: From Physiological Response to Injury Factor. OXIDATIVE MEDICINE AND CELLULAR LONGEVITY 2020; 2020:5732956. [PMID: 32509147 PMCID: PMC7244977 DOI: 10.1155/2020/5732956] [Citation(s) in RCA: 119] [Impact Index Per Article: 29.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/18/2019] [Revised: 01/11/2020] [Accepted: 04/22/2020] [Indexed: 02/07/2023]
Abstract
Reactive oxygen species (ROS) are highly reactive chemical species containing oxygen, controlled by both enzymatic and nonenzymatic antioxidant defense systems. In the heart, ROS play an important role in cell homeostasis, by modulating cell proliferation, differentiation, and excitation-contraction coupling. Oxidative stress occurs when ROS production exceeds the buffering capacity of the antioxidant defense systems, leading to cellular and molecular abnormalities, ultimately resulting in cardiac dysfunction. In this review, we will discuss the physiological sources of ROS in the heart, the mechanisms of oxidative stress-related myocardial injury, and the implications of experimental studies and clinical trials with antioxidant therapies in cardiovascular diseases.
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12
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Greaney JL, Stanhewicz AE, Kenney WL. Chronic statin therapy is associated with enhanced cutaneous vascular responsiveness to sympathetic outflow during passive heat stress. J Physiol 2019; 597:4743-4755. [PMID: 31397898 DOI: 10.1113/jp278237] [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] [Received: 05/02/2019] [Accepted: 08/08/2019] [Indexed: 12/20/2022] Open
Abstract
KEY POINTS Impairments in both central sympathetic and peripheral microvascular function contribute to blunted reflex cutaneous vasodilatation during heat stress in healthy older adults. Hypercholesterolaemia is associated with decrements in neurovascular function; however, little is known about the impact of hypercholesterolaemia on the integrated responses to heat stress. Further, whether chronic statin therapy alters skin sympathetic outflow or its relation to cutaneous vascular conductance during heat stress is unknown. We demonstrate that reflex cutaneous vasodilatation is impaired in older hypercholesterolaemic adults but not in formerly hypercholesterolaemic adults currently treated with a statin compared to age-matched controls. Additionally, chronic statin treatment-induced improvements in reflex vasodilatation are mediated, in part, by increases in end-organ responsiveness to efferent sympathetic outflow during whole-body heating. These data add to the growing body of literature substantiating the beneficial pleiotropic neurovascular effects of chronic statin treatment and provide further support for the use of statins to confer additional cardioprotective benefits in older adults. ABSTRACT Attenuated reflex cutaneous vasodilatation in healthy human ageing is mediated by alterations in both central (sympathetic outflow) and peripheral (microvascular endothelial) function. Hypercholesterolaemia is associated with further impairments in neurovascular function. HMG-CoA reductase inhibitors (statins) improve cutaneous endothelium-dependent dilatation; however, whether statin therapy alters skin sympathetic nervous system activity (SSNA) or its relation to cutaneous vascular conductance (CVC) during passive heat stress is unknown. We hypothesized that (1) hypercholesterolaemic older adults would demonstrate blunted increases in both SSNA and CVC during passive heating and (2) chronic statin treatment would improve the response range and sensitivity of the SSNA:CVC relation. Reflex vasodilatation in response to a 1.0°C rise in oral temperature (Tor ; water perfused suit) was induced in 13 healthy normocholesterolaemic adults (62 ± 2 years; LDL = 113 ± 7 mg/dl), 10 hypercholesterolaemic adults (60 ± 1 years; LDL = 183 ± 2 mg/dl), and 10 previously hypercholesterolaemic adults (64 ± 1 years; LDL = 102 ± 2 mg/dl) treated with lipophilic statin (10-40 mg daily). SSNA (peroneal microneurography) and red cell flux (laser-Doppler flowmetry) in the innervated dermatome (dorsum of foot) were continuously measured. Reflex vasodilatation was blunted in hypercholesterolaemic adults, but not in statin-treated adults, compared to normocholesterolaemic adults (at ∆Tor = 1.0°C: normal = 36 ± 1%CVCmax , high = 32 ± 1%CVCmax , statin = 38 ± 1%CVCmax ; P < 0.01). ∆SSNA was not different (at ∆Tor = 1.0°C: normal: ∆ = 393 ± 96%, high: ∆ = 311 ± 120%, statin: ∆ = 256 ± 90%; P = 0.11). The slope of the SSNA:CVC relation was blunted in hypercholesterolaemic adults (0.02 ± 0.03%CVCmax /%baseline ) compared to both normocholesterolaemic (0.09 ± 0.02%CVCmax /%baseline ; P = 0.024) and statin-treated (0.12 ± 0.05%CVCmax /%baseline ; P = 0.03) adults. Chronic statin treatment improves reflex cutaneous vasodilatation in formerly hypercholesterolaemic older adults by increasing end-organ responsiveness to sympathetic outflow during passive heat stress.
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Affiliation(s)
- Jody L Greaney
- Noll Laboratory, Department of Kinesiology, The Pennsylvania State University, University Park, PA, USA.,Department of Kinesiology, The University of Texas at Arlington, Arlington, TX, USA
| | - Anna E Stanhewicz
- Noll Laboratory, Department of Kinesiology, The Pennsylvania State University, University Park, PA, USA
| | - W Larry Kenney
- Noll Laboratory, Department of Kinesiology, The Pennsylvania State University, University Park, PA, USA
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13
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Young BE, Holwerda SW, Vranish JR, Keller DM, Fadel PJ. Sympathetic Transduction in Type 2 Diabetes Mellitus. Hypertension 2019; 74:201-207. [PMID: 31188673 DOI: 10.1161/hypertensionaha.119.12928] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Approximately 60% of patients with type 2 diabetes mellitus (T2D) develop hypertension. Recent work also indicates greater blood pressure (BP) excursions throughout the day in T2D. Collectively, these findings suggest altered BP control in T2D. Although muscle sympathetic nerve activity (MSNA) recordings in T2D have provided equivocal results, quantification of MSNA alone does not account for ensuing vasoconstriction and BP responses elicited by MSNA. Thus, we tested the hypothesis that patients with T2D exhibit enhanced sympathetic transduction to BP. MSNA (microneurography) and beat-to-beat BP (Finometer) were measured at rest in 21 T2D and 13 age-matched and body mass index-matched control subjects and, signal-averaging was performed to quantify the mean arterial pressure and total vascular conductance responses to spontaneous bursts of MSNA. The peak mean arterial pressure and total vascular conductance responses to spontaneous MSNA were similar between T2D and control (both P>0.05). However, further analysis, separating T2D into those taking statins (n=13, T2D +statin) and not taking statins (n=8, T2D -statin), indicated that T2D -statin patients (4.2±0.6 mm Hg) exhibited greater peak mean arterial pressure responses compared with both T2D +statin patients (2.5±0.3 mm Hg, P=0.01) and control (control: 2.8±0.3 mm Hg, P=0.02). Likewise, nadir total vascular conductance responses to spontaneous MSNA bursts were greater in T2D -statin patients (T2D -statin: -3.3±0.6 mL/(min·mm Hg), T2D +statin: -1.6±0.3 mL/(min·mm Hg), P=0.03; control -2.2±0.3 mL/(min·mm Hg), P=0.08). Notably, T2D +statin patients exhibited similar peak mean arterial pressure and total vascular conductance responses to MSNA compared with control. Collectively, these findings demonstrate, for the first time, that patients with T2D exhibit augmented sympathetic transduction and this effect seems to be offset by statin therapy.
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Affiliation(s)
- Benjamin E Young
- From the Department of Kinesiology, University of Texas at Arlington (B.E.Y., D.M.K., P.J.F.)
| | - Seth W Holwerda
- Department of Health and Human Physiology, University of Iowa (S.W.H.)
| | - Jennifer R Vranish
- Department of Integrative Physiology and Health Science, Alma College, MI (J.R.V.)
| | - David M Keller
- From the Department of Kinesiology, University of Texas at Arlington (B.E.Y., D.M.K., P.J.F.)
| | - Paul J Fadel
- From the Department of Kinesiology, University of Texas at Arlington (B.E.Y., D.M.K., P.J.F.)
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14
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Kakehi K, Iwanaga Y, Watanabe H, Sonobe T, Akiyama T, Shimizu S, Yamamoto H, Miyazaki S. Modulation of Sympathetic Activity and Innervation With Chronic Ivabradine and β-Blocker Therapies: Analysis of Hypertensive Rats With Heart Failure. J Cardiovasc Pharmacol Ther 2019; 24:387-396. [PMID: 30786751 DOI: 10.1177/1074248419829168] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
BACKGROUND Whether the reduction of heart rate with ivabradine (IVA) could affect sympathetic activation and cardiac innervation in heart failure (HF) remains unknown. PURPOSE The present study assessed the chronic effects of IVA and β-blocker on the systemic and local sympathetic nervous systems of hypertensive animals with HF. METHODS AND RESULTS The Dahl salt-sensitive rats received chronic IVA, bisoprolol (BIS), or placebo (CTL) therapy. The survival of the animal models with IVA and BIS significantly improved (median; 19.7 in IVA and 19.7 in BIS vs 17.0 weeks in CTL, P < .001). A similar decrease in 24-hour heart rate (mean; 305 in IVA and 329 in BIS vs 388 beats/min in CTL, P < .001) without effect on blood pressure, and an improvement in the left ventricular dysfunction (mean fractional shortening; 56.7% in IVA and 47.8% in BIS vs 39.0% in CTL, P < .001) were observed in the animals with IVA and BIS. However, a negative inotropic effect was only observed in the animals with BIS. Excessive urinary noradrenaline excretion in animals with CTL was only suppressed with the use of IVA (mean; 1.35 μg/d in IVA and 1.95 μg/d in BIS vs 2.27 μg/d in CTL, P = .002). In contrast, atrial noradrenaline and acetylcholine depletion in the animals with CTL improved and the tyrosine hydroxylase expression in the both atria were restored with the use of both IVA and BIS. CONCLUSIONS IVA therapy improved the survival of hypertensive animals with HF. Furthermore, it was associated with the amelioration of systemic sympathetic activation and cardiac sympathetic and parasympathetic nerve innervations. Chronic β-blocker therapy with negative inotropic effects had beneficial effects only on cardiac innervations.
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Affiliation(s)
- Kazuyoshi Kakehi
- 1 Division of Cardiology, Department of Internal Medicine, Kindai University Faculty of Medicine, Osakasayama, Japan
| | - Yoshitaka Iwanaga
- 1 Division of Cardiology, Department of Internal Medicine, Kindai University Faculty of Medicine, Osakasayama, Japan
| | - Heitaro Watanabe
- 1 Division of Cardiology, Department of Internal Medicine, Kindai University Faculty of Medicine, Osakasayama, Japan
| | - Takashi Sonobe
- 2 Department of Cardiac Physiology, National Cerebral and Cardiovascular Center, Suita, Japan
| | - Tsuyoshi Akiyama
- 2 Department of Cardiac Physiology, National Cerebral and Cardiovascular Center, Suita, Japan
| | - Shuji Shimizu
- 3 Department of Cardiovascular Dynamics, National Cerebral and Cardiovascular Center, Suita, Japan
| | - Hiromi Yamamoto
- 1 Division of Cardiology, Department of Internal Medicine, Kindai University Faculty of Medicine, Osakasayama, Japan
| | - Shunichi Miyazaki
- 1 Division of Cardiology, Department of Internal Medicine, Kindai University Faculty of Medicine, Osakasayama, Japan
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15
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Cobalt(II), nickel(II) and zinc(II) coordination chemistry of the N,N′-disubstituted hydroxylamine-(diamido) ligand, 3,3′-(hydroxyazanediyl)dipropanamide. Polyhedron 2018. [DOI: 10.1016/j.poly.2018.06.002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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16
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Moralez G, Jouett NP, Tian J, Zimmerman MC, Bhella P, Raven PB. Effect of centrally acting angiotensin converting enzyme inhibitor on the exercise-induced increases in muscle sympathetic nerve activity. J Physiol 2018; 596:2315-2332. [PMID: 29635787 PMCID: PMC6002210 DOI: 10.1113/jp274697] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2018] [Accepted: 03/21/2018] [Indexed: 01/01/2023] Open
Abstract
KEY POINTS The arterial baroreflex's operating point pressure is reset upwards and rightwards from rest in direct relation to the increases in dynamic exercise intensity. The intraneural pathways and signalling mechanisms that lead to upwards and rightwards resetting of the operating point pressure, and hence the increases in central sympathetic outflow during exercise, remain to be identified. We tested the hypothesis that the central production of angiotensin II during dynamic exercise mediates the increases in sympathetic outflow and, therefore, the arterial baroreflex operating point pressure resetting during acute and prolonged dynamic exercise. The results identify that perindopril, a centrally acting angiotensin converting enzyme inhibitor, markedly attenuates the central sympathetic outflow during acute and prolonged dynamic exercise. ABSTRACT We tested the hypothesis that the signalling mechanisms associated with the dynamic exercise intensity related increases in muscle sympathetic nerve activity (MSNA) and arterial baroreflex resetting during exercise are located within the central nervous system. Participants performed three randomly ordered trials of 70° upright back-supported dynamic leg cycling after ingestion of placebo and two different lipid soluble angiotensin converting enzyme inhibitors (ACEi): perindopril (high lipid solubility), captopril (low lipid solubility). Repeated measurements of whole venous blood (n = 8), MSNA (n = 7) and arterial blood pressures (n = 14) were obtained at rest and during an acute (SS1) and prolonged (SS2) bout of steady state dynamic exercise. Arterial baroreflex function curves were modelled at rest and during exercise. Peripheral venous superoxide concentrations measured by electron spin resonance spectroscopy were elevated during exercise and were not altered by ACEi at rest (P ≥ 0.4) or during exercise (P ≥ 0.3). Baseline MSNA and mean arterial pressure were unchanged at rest (P ≥ 0.1; P ≥ 0.8, respectively). However, during both SS1 and SS2, the centrally acting ACEi perindopril attenuated MSNA compared to captopril and the placebo (P < 0.05). Arterial pressures at the operating point and threshold pressures were decreased with perindopril from baseline to SS1 with no further changes in the operating point pressure during SS2 under all three conditions. These data suggest that centrally acting ACEi is significantly more effective at attenuating the increase in the acute and prolonged exercise-induced increases in MSNA.
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Affiliation(s)
- Gilbert Moralez
- Institute for Cardiovascular and Metabolic DiseaseUniversity of North Texas Health Science CenterFort WorthTXUSA
- Institute for Exercise and Environmental MedicineTexas Health Presbyterian Hospital Dallas and The University of Texas Southwestern Medical CenterDallasTXUSA
| | - Noah P. Jouett
- Institute for Cardiovascular and Metabolic DiseaseUniversity of North Texas Health Science CenterFort WorthTXUSA
| | - Jun Tian
- Department of Cellular and Integrative PhysiologyUniversity of Nebraska Medical CenterOmahaNEUSA
| | - Matthew C. Zimmerman
- Department of Cellular and Integrative PhysiologyUniversity of Nebraska Medical CenterOmahaNEUSA
| | - Paul Bhella
- Department of Cardiac Imaging at the John Peter Smith Health NetworkFort WorthTXUSA
- Department of Internal MedicineTCU and UNTHSC School of MedicineFort WorthTXUSA
| | - Peter B. Raven
- Institute for Cardiovascular and Metabolic DiseaseUniversity of North Texas Health Science CenterFort WorthTXUSA
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17
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Differential effects of lipophilic and hydrophilic statins on muscle sympathetic nerve activity in heart failure with preserved left ventricular ejection fraction. Auton Neurosci 2018; 213:8-14. [PMID: 30005743 DOI: 10.1016/j.autneu.2018.04.006] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2018] [Revised: 04/24/2018] [Accepted: 04/27/2018] [Indexed: 11/23/2022]
Abstract
Augmented sympathetic nerve activity is associated with heart failure with preserved left ventricular ejection fraction (HFpEF). Lipophilic statins reduce sympathetic nerve activity in patients with heart failure with reduced left ventricular ejection fraction. However, little is known about whether all types of statins, regardless of solubility, reduce sympathetic nerve activity in HFpEF. We evaluated the effect of atorvastatin, a lipophilic statin, and rosuvastatin, a hydrophilic statin, on muscle sympathetic nerve activity (MSNA) in HFpEF patients. This study was conducted as a prospective, randomized, open-label, crossover trial. Ten HFpEF patients with untreated hyperlipidemia participated in this study. Subjects were assigned to either the atorvastatin (lipophilic) or the rosuvastatin (hydrophilic) group with each drug administered for 8 weeks. Atorvastatin and rosuvastatin treatment resulted in a similar reduction in low-density lipoprotein cholesterol (LDL-C) levels. There was no difference in the effect of either treatment on blood pressure, heart rate, or left ventricular function. Atorvastatin significantly decreased MSNA frequency compared with baseline (31.5 ± 6.3 vs. 47.5 ± 10.7 bursts/min, p < 0.01), but rosuvastatin had no effect on MSNA (40.9 ± 7.3 bursts/min). MSNA was significantly lower in the atorvastatin group than rosuvastatin group (p < 0.05). However, the reduction in MSNA seen in either group did not correlate with the reduction in LDL-C. No significant differences were observed in either the baroreflex control of heart rate or MSNA between the two groups. These results suggest that lipophilic statins have a favorable effect on sympathetic nerve activity beyond lowering LDL-C in HFpEF, but hydrophilic statins do not.
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18
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Cao Q, Zhang J, Gao L, Zhang Y, Dai M, Bao M. Dickkopf‑3 upregulation mediates the cardioprotective effects of curcumin on chronic heart failure. Mol Med Rep 2018; 17:7249-7257. [PMID: 29568962 PMCID: PMC5928680 DOI: 10.3892/mmr.2018.8783] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2017] [Accepted: 02/28/2018] [Indexed: 01/20/2023] Open
Abstract
Curcumin, isolated from rhizome of turmeric, has been widely studied as a potential therapeutic drug for cancer. However, protective effects of curcumin on chronic heart failure (CHF) have not been fully studied. In the present study, the effects of curcumin on CHF and the underlying mechanisms were investigated. A total of 40 rabbits were randomized into 4 groups: Control rabbits fed with placebo (Con) or curcumin (Con‑cur), CHF rabbits fed with placebo (CHF) or curcumin (CHF‑cur). CHF was induced by volume and pressure overload. The effects of curcumin on cardiac function and left ventricular (LV) structure were assessed by echocardiography and histology. The effects of curcumin on CHF molecular biomarkers were detected by dihydroethidium and immunohistochemical staining. The effects of curcumin on Dickkopf‑related protein 3 (DKK‑3), p38 mitogen‑activated protein kinase (p38), c‑Jun N‑terminal kinase (JNK) and apoptosis signal‑regulating kinase 1 (ASK1) were assessed by immunohistochemical staining and western blot analysis. Cardiac dysfunction and LV remodeling were successfully produced by ten weeks volume overload and eight weeks pressure overload in the CHF group. Compared with the Con group, the CHF group demonstrated higher levels of CHF molecular biomarkers, a lower level of DKK‑3 expression and alterations of p38, JNK and ASK1 protein expression. Curcumin alleviated all those abnormalities markedly in the CHF‑cur group. In summary, curcumin may exert cardioprotective effects by up‑regulating DKK‑3, which in turn may inhibit p38 and JNK signaling pathways in an ASK1‑dependent way. The present study demonstrated that Dickkopf‑3 upregulation mediates the cardioprotective effects of curcumin on chronic heart failure for the first time.
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Affiliation(s)
- Quan Cao
- Department of Cardiology, Renmin Hospital of Wuhan University, Wuhan, Hubei 430060, P.R. China
| | - Junxia Zhang
- Department of Endocrinology, Wuhan General Hospital of the Chinese People's Liberation Army, Wuhan, Hubei 430070, P.R. China
| | - Ling Gao
- Department of Endocrinology and Metabolism, Renmin Hospital of Wuhan University, Wuhan, Hubei 430060, P.R. China
| | - Yijie Zhang
- Department of Cardiology, Renmin Hospital of Wuhan University, Wuhan, Hubei 430060, P.R. China
| | - Mingyan Dai
- Department of Cardiology, Renmin Hospital of Wuhan University, Wuhan, Hubei 430060, P.R. China
| | - Mingwei Bao
- Department of Cardiology, Renmin Hospital of Wuhan University, Wuhan, Hubei 430060, P.R. China
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Kaur J, Young BE, Fadel PJ. Sympathetic Overactivity in Chronic Kidney Disease: Consequences and Mechanisms. Int J Mol Sci 2017; 18:ijms18081682. [PMID: 28767097 PMCID: PMC5578072 DOI: 10.3390/ijms18081682] [Citation(s) in RCA: 79] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2017] [Revised: 07/20/2017] [Accepted: 07/28/2017] [Indexed: 12/19/2022] Open
Abstract
The incidence of chronic kidney disease (CKD) is increasing worldwide, with more than 26 million people suffering from CKD in the United States alone. More patients with CKD die of cardiovascular complications than progress to dialysis. Over 80% of CKD patients have hypertension, which is associated with increased risk of cardiovascular morbidity and mortality. Another common, perhaps underappreciated, feature of CKD is an overactive sympathetic nervous system. This elevation in sympathetic nerve activity (SNA) not only contributes to hypertension but also plays a detrimental role in the progression of CKD independent of any increase in blood pressure. Indeed, high SNA is associated with poor prognosis and increased cardiovascular morbidity and mortality independent of its effect on blood pressure. This brief review will discuss some of the consequences of sympathetic overactivity and highlight some of the potential pathways contributing to chronically elevated SNA in CKD. Mechanisms leading to chronic sympathoexcitation in CKD are complex, multifactorial and to date, not completely understood. Identification of the mechanisms and/or signals leading to sympathetic overactivity in CKD are crucial for development of effective therapeutic targets to reduce the increased cardiovascular risk in this patient group.
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Affiliation(s)
- Jasdeep Kaur
- Department of Kinesiology, University of Texas at Arlington, Arlington, TX 76019, USA.
| | - Benjamin E Young
- Department of Kinesiology, University of Texas at Arlington, Arlington, TX 76019, USA.
| | - Paul J Fadel
- Department of Kinesiology, University of Texas at Arlington, Arlington, TX 76019, USA.
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20
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Thompson K, Razi R, Lee MS, Shen A, Stone GW, Hiremath S, Mehran R, Brar SS. Statin use prior to angiography for the prevention of contrast-induced acute kidney injury: a meta-analysis of 19 randomised trials. EUROINTERVENTION 2017; 12:366-74. [PMID: 25982920 DOI: 10.4244/eijy15m05_03] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
AIMS A systematic review and a meta-analysis were performed to define better the role of statin use prior to angiography in preventing contrast-induced acute kidney injury (CI-AKI). METHODS AND RESULTS MEDLINE, Embase, Cochrane Library, references from review articles, and conference proceedings were searched, with no language restriction, for randomised controlled trials (RCT) evaluating the use of statin therapy prior to angiography for the prevention of CI-AKI. Nineteen RCTs including 7,161 patients were identified. The pooled analysis demonstrated a significant reduction in the incidence of CI-AKI in patients treated with statin prior to invasive angiography when compared with control (RR 0.52; 95% CI: 0.40-0.67). Patients with chronic kidney disease stage 3 or worse were largely underrepresented in these trials, and statin therapy did not significantly reduce the risk of CI-AKI in the three studies which enrolled a patient population with a mean eGFR of <60 ml/min (RR 0.54; 95% CI: 0.2-1.42). CONCLUSIONS This meta-analysis suggests a potential benefit for statin use prior to angiography to reduce the incidence of CI-AKI. Additional research is needed to define better the benefits of statin therapy prior to angiography to prevent CI-AKI, especially in high-risk patients with chronic kidney disease who were largely underrepresented in the available trials.
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21
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Eikelis N, Lambert EA, Phillips S, Sari CI, Mundra PA, Weir JM, Huynh K, Grima MT, Straznicky NE, Dixon JB, Schlaich MP, Meikle PJ, Lambert GW. Muscle Sympathetic Nerve Activity Is Associated With Elements of the Plasma Lipidomic Profile in Young Asian Adults. J Clin Endocrinol Metab 2017; 102:2059-2068. [PMID: 28323975 DOI: 10.1210/jc.2016-3738] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/20/2016] [Accepted: 03/10/2017] [Indexed: 02/13/2023]
Abstract
BACKGROUND Asian subjects are at increased cardio-metabolic risk at comparatively lower body mass index (BMI) compared with white subjects. Sympathetic nervous system activation and dyslipidemia, both characteristics of increased adiposity, appear to be related. We therefore analyzed the association of muscle sympathetic nerve activity (MSNA) with the plasma lipidomic profile in young adult Asian and white subjects. METHODS Blood samples were collected from 101 participants of either Asian or white background (age, 18 to 30 years; BMI, 28.1 ± 5.9 kg/m2). Lipids were extracted from plasma and analyzed using electrospray ionization-tandem mass spectrometry. MSNA was quantified using microneurography. The association of MSNA and obesity with lipid species was examined using linear regression analysis. RESULTS The plasma concentrations of total dihydroceramide, ceramide, GM3 ganglioside, lysoalkylphosphatidylcholine, alkenylphosphatidylethanolamine, and lysophosphatidylinositol were elevated in the Asian subjects relative to the white subjects. After adjustment for confounders, diacylglycerols and triacylglycerols, cholesterol esters, phosphatidylinositols, phosphatidylethanolamines, and phosphatidylglycerols bore significant associations with MSNA but only in the Asian subjects. These associations remained significant after further adjustment for the participants' degree of insulin resistance and appeared not to be related to differences in diet macronutrient content between groups. CONCLUSIONS The lipidomic profile differs between Asian and white subjects. There exists a strong relationship between certain lipid species and MSNA. The association is stronger in Asian subjects, despite their lower BMI. This study demonstrates an association between circulating lipids and central sympathetic outflow. Whether the stronger association between the lipid profile and sympathetic activation underpins the apparent greater risk posed by increased adiposity in Asian individuals merits further attention.
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Affiliation(s)
- Nina Eikelis
- Human Neurotransmitters, Baker Heart & Diabetes Institute, Melbourne, Victoria 3004, Australia
- Iverson Health Innovation Research Institute, Swinburne University of Technology, Melbourne, Victoria 3122, Australia
| | - Elisabeth A Lambert
- Human Neurotransmitters, Baker Heart & Diabetes Institute, Melbourne, Victoria 3004, Australia
- Iverson Health Innovation Research Institute, Swinburne University of Technology, Melbourne, Victoria 3122, Australia
| | - Sarah Phillips
- Human Neurotransmitters, Baker Heart & Diabetes Institute, Melbourne, Victoria 3004, Australia
- Iverson Health Innovation Research Institute, Swinburne University of Technology, Melbourne, Victoria 3122, Australia
| | - Carolina Ika Sari
- Human Neurotransmitters, Baker Heart & Diabetes Institute, Melbourne, Victoria 3004, Australia
| | - Piyushkumar A Mundra
- Metabolomics Laboratories, Baker Heart & Diabetes Institute, Melbourne, Victoria 3004, Australia
| | - Jacquelyn M Weir
- Metabolomics Laboratories, Baker Heart & Diabetes Institute, Melbourne, Victoria 3004, Australia
| | - Kevin Huynh
- Metabolomics Laboratories, Baker Heart & Diabetes Institute, Melbourne, Victoria 3004, Australia
| | - Mariee T Grima
- Human Neurotransmitters, Baker Heart & Diabetes Institute, Melbourne, Victoria 3004, Australia
| | - Nora E Straznicky
- Human Neurotransmitters, Baker Heart & Diabetes Institute, Melbourne, Victoria 3004, Australia
| | - John B Dixon
- Human Neurotransmitters, Baker Heart & Diabetes Institute, Melbourne, Victoria 3004, Australia
- Primary Care Research, Monash University, Melbourne, Victoria 3800, Australia
| | - Markus P Schlaich
- Neurovascular Hypertension & Kidney Disease, Baker Heart & Diabetes Institute, Melbourne, Victoria 3004, Australia
- Dobney Hypertension Centre, School of Medicine, University of Western Australia - Royal Perth Hospital Unit, University of Western Australia, Perth, Western Australia 6000, Australia
| | - Peter J Meikle
- Metabolomics Laboratories, Baker Heart & Diabetes Institute, Melbourne, Victoria 3004, Australia
| | - Gavin W Lambert
- Human Neurotransmitters, Baker Heart & Diabetes Institute, Melbourne, Victoria 3004, Australia
- Iverson Health Innovation Research Institute, Swinburne University of Technology, Melbourne, Victoria 3122, Australia
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Zuo L, Chuang CC, Clark AD, Garrison DE, Kuhlman JL, Sypert DC. Reactive Oxygen Species in COPD-Related Vascular Remodeling. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2017; 967:399-411. [PMID: 29047102 DOI: 10.1007/978-3-319-63245-2_26] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
The pathogenesis of chronic obstructive pulmonary disease (COPD) is a multifaceted process involving the alteration of pulmonary vasculature. Such vascular remodeling can be associated with inflammation, shear stress, and hypoxia-conditions commonly seen in patients with lung diseases. Particularly, the overproduction of reactive oxygen species (ROS) in the diseased lungs contributes greatly to pulmonary vascular remodeling. ROS play an important role in vascular homeostasis, yet excessive ROS can alter pulmonary vasculature and impair lung function, as implicated in COPD at all stages. Increased inflammatory cell infiltration and endothelial dysfunction both correspond to the severity of COPD. As a byproduct of vascular remodeling, pulmonary hypertension negatively affects the long-term survival rate of COPD patients. While there is currently no cure for COPD, several treatment options have focused on alleviating COPD symptoms. Interventions such as long-term oxygen therapy, endothelium-targeted treatment, and pharmacological therapies show promising results in improving the life span of COPD patients and attenuating the progression of pulmonary hypertension. In this chapter, we aim to discuss the contributing factors of pulmonary vascular remodeling in COPD with an emphasis on the ROS, as well as potential redox treatments for COPD-related vascular remodeling.
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Affiliation(s)
- Li Zuo
- Molecular Physiology and Rehabilitation Research Laboratory, Radiologic Sciences and Respiratory Therapy Division, School of Health and Rehabilitation Sciences, The Ohio State University College of Medicine, The Ohio State University Wexner Medical Center, Columbus, OH, 43210, USA.
| | - Chia-Chen Chuang
- Molecular Physiology and Rehabilitation Research Laboratory, Radiologic Sciences and Respiratory Therapy Division, School of Health and Rehabilitation Sciences, The Ohio State University College of Medicine, The Ohio State University Wexner Medical Center, Columbus, OH, 43210, USA
| | - Alexander D Clark
- Molecular Physiology and Rehabilitation Research Laboratory, Radiologic Sciences and Respiratory Therapy Division, School of Health and Rehabilitation Sciences, The Ohio State University College of Medicine, The Ohio State University Wexner Medical Center, Columbus, OH, 43210, USA
| | - Davis E Garrison
- Molecular Physiology and Rehabilitation Research Laboratory, Radiologic Sciences and Respiratory Therapy Division, School of Health and Rehabilitation Sciences, The Ohio State University College of Medicine, The Ohio State University Wexner Medical Center, Columbus, OH, 43210, USA
| | - Jamie L Kuhlman
- Molecular Physiology and Rehabilitation Research Laboratory, Radiologic Sciences and Respiratory Therapy Division, School of Health and Rehabilitation Sciences, The Ohio State University College of Medicine, The Ohio State University Wexner Medical Center, Columbus, OH, 43210, USA
| | - David C Sypert
- Molecular Physiology and Rehabilitation Research Laboratory, Radiologic Sciences and Respiratory Therapy Division, School of Health and Rehabilitation Sciences, The Ohio State University College of Medicine, The Ohio State University Wexner Medical Center, Columbus, OH, 43210, USA
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Pellegrino PR, Schiller AM, Haack KKV, Zucker IH. Central Angiotensin-II Increases Blood Pressure and Sympathetic Outflow via Rho Kinase Activation in Conscious Rabbits. Hypertension 2016; 68:1271-1280. [PMID: 27672026 DOI: 10.1161/hypertensionaha.116.07792] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2016] [Accepted: 08/25/2016] [Indexed: 01/08/2023]
Abstract
Elevated sympathetic tone and activation of the renin-angiotensin system are pathophysiologic hallmarks of hypertension, and the interactions between these systems are particularly deleterious. The importance of Rho kinase as a mediator of the effects of angiotensin-II (AngII) in the periphery is clear, but the role of Rho kinase in sympathoexcitation caused by central AngII is not well established. We hypothesized that AngII mediates its effects in the brain by the activation of the RhoA/Rho kinase pathway. Chronically instrumented, conscious rabbits received the following intracerebroventricular infusion treatments for 2 weeks via osmotic minipump: AngII, Rho kinase inhibitor Fasudil, AngII plus Fasudil, or a vehicle control. AngII increased mean arterial pressure over the course of the infusion, and this effect was prevented by the coadministration of Fasudil. AngII increased cardiac and vascular sympathetic outflow as quantified by the heart rate response to metoprolol and the depressor effect of hexamethonium; coadministration of Fasudil abolished both of these effects. AngII increased baseline renal sympathetic nerve activity in conscious animals and impaired baroreflex control of sympathetic nerve activity; again Fasudil coinfusion prevented these effects. Each of these end points showed a statistically significant interaction between AngII and Fasudil. Quantitative immunofluorescence of brain slices confirmed that Rho kinase activity was increased by AngII and decreased by Fasudil. Taken together, these data indicate that hypertension, elevated sympathetic outflow, and baroreflex dysfunction caused by central AngII are mediated by Rho kinase activation and suggest that Rho kinase inhibition may be an important therapeutic target in sympathoexcitatory cardiovascular diseases.
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Affiliation(s)
- Peter R Pellegrino
- From the Department of Cellular and Integrative Physiology, University of Nebraska Medical Center, Omaha (P.R.P., A.M.S., I.H.Z.); U.S. Army Institute of Surgical Research, Fort Sam Houston, TX (A.M.S.); and Department of Pediatrics, Emory University School of Medicine, Atlanta, GA (K.K.V.H.)
| | - Alicia M Schiller
- From the Department of Cellular and Integrative Physiology, University of Nebraska Medical Center, Omaha (P.R.P., A.M.S., I.H.Z.); U.S. Army Institute of Surgical Research, Fort Sam Houston, TX (A.M.S.); and Department of Pediatrics, Emory University School of Medicine, Atlanta, GA (K.K.V.H.)
| | - Karla K V Haack
- From the Department of Cellular and Integrative Physiology, University of Nebraska Medical Center, Omaha (P.R.P., A.M.S., I.H.Z.); U.S. Army Institute of Surgical Research, Fort Sam Houston, TX (A.M.S.); and Department of Pediatrics, Emory University School of Medicine, Atlanta, GA (K.K.V.H.)
| | - Irving H Zucker
- From the Department of Cellular and Integrative Physiology, University of Nebraska Medical Center, Omaha (P.R.P., A.M.S., I.H.Z.); U.S. Army Institute of Surgical Research, Fort Sam Houston, TX (A.M.S.); and Department of Pediatrics, Emory University School of Medicine, Atlanta, GA (K.K.V.H.).
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Ma Y, Kong L, Qi S, Wang D. Atorvastatin blocks increased l-type Ca2+ current and cell injury elicited by angiotensin II via inhibiting oxide stress. Acta Biochim Biophys Sin (Shanghai) 2016; 48:378-84. [PMID: 26940997 DOI: 10.1093/abbs/gmw009] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2015] [Accepted: 12/12/2015] [Indexed: 12/13/2022] Open
Abstract
Thel-type Ca(2+)current (ICa,l) plays a crucial role in shaping action potential and is involved in cardiac arrhythmia. Statins have been demonstrated to contribute to anti-apoptotic and anti-arrhythmic effects in the heart. Here, we examined whether atorvastatin regulates theICa,land cell injury induced by angiotensin II (AngII) as well as the putative intracellular cascade responsible for the effects. Cultured neonatal rat ventricular myocytes were incubated with AngII for 24 h, and then cell injury and expression levels of Nox2/gp91(phox), p47(phox) ,and Cav1.2 were analyzed. In addition,ICa,lwas recorded using the whole-cell patch-clamp technique, and mechanisms of atorvastatin actions were also investigated. It was found that the number of apoptotic cardiomyocytes was increased and cell viability was significantly decreased after AngII administration. AngII also augmented the expressions of Nox2/gp91(phox)and p47(phox)compared with control cardiomyocytes. Exposure to AngII evokedICa,lin a voltage-dependent manner without affecting theI-Vrelationship. In addition, AngII enhanced membrane Cav1.2 expression. These effects were abolished in the presence of the reactive oxygen species (ROS) scavenger, manganese (III)-tetrakis 4-benzoic acid porphyrin [Mn(III)TBAP], or the 3-hydroxy-3-methylglutaryl-CoA reductase inhibitor, atorvastatin. These results suggested that atorvastatin mediates cardioprotection against arrhythmias and cell injury by controlling the AngII-ROS cascade.
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Affiliation(s)
- Yanzhuo Ma
- Department of Cardiology, Bethune International Peace Hospital, Shijiazhuang 050000, China
| | - Lingfeng Kong
- Department of Cardiology, Bethune International Peace Hospital, Shijiazhuang 050000, China Hebei Medical University, Shijiazhuang 050011, China
| | - Shuying Qi
- Department of Cardiology, Bethune International Peace Hospital, Shijiazhuang 050000, China
| | - Dongmei Wang
- Department of Cardiology, Bethune International Peace Hospital, Shijiazhuang 050000, China
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Jouett NP, Moralez G, White DW, Eubank WL, Chen S, Tian J, Smith ML, Zimmerman MC, Raven PB. N-Acetylcysteine reduces hyperacute intermittent hypoxia-induced sympathoexcitation in human subjects. Exp Physiol 2016; 101:387-96. [PMID: 27027616 DOI: 10.1113/ep085546] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2015] [Accepted: 01/12/2016] [Indexed: 01/31/2023]
Abstract
NEW FINDINGS What is the central question of this study? This study evaluated the following central question: does N-acetylcysteine (N-AC), an antioxidant that readily penetrates the blood-brain barrier, have the capability to reduce the increase in sympathetic nerve activity observed during hyperacute intermittent hypoxia? What is the main finding and its importance? We demonstrate that N-AC decreases muscle sympathetic nerve activity in response to hyperacute intermittent hypoxia versus placebo control. This finding suggests that antioxidants, such as N-AC, have therapeutic potential in obstructive sleep apnoea. This investigation tested the following hypotheses: that (i) N-acetylcysteine (N-AC) attenuates hyperacute intermittent hypoxia-induced sympathoexcitation, (ii) without elevating superoxide measured in peripheral venous blood. Twenty-eight healthy human subjects were recruited to the study. One hour before experimentation, each subject randomly ingested either 70 mg kg(-1) of N-AC (n = 16) or vehicle placebo (n = 12). Three-lead ECG and arterial blood pressure, muscle sympathetic nerve activity (n = 17) and whole-blood superoxide concentration (using electron paramagnetic resonance spectroscopy; n = 12) were measured. Subjects underwent a 20 min hyperacute intermittent hypoxia training (hAIHT) protocol that consisted of cyclical end-expiratory apnoeas with 100% nitrogen. N-AC decreased muscle sympathetic nerve activity after hAIHT compared with placebo (P < 0.02). However, N-AC did not alter superoxide concentrations in venous blood compared with placebo (P > 0.05). Moreover, hAIHT did not increase superoxide concentrations in the peripheral circulation as measured by electron paramagnetic resonance (P > 0.05). Based on these findings, we contend that (i) hAIHT and (ii) the actions of N-AC in hAIHT are primarily mediated centrally rather than peripherally, although central measurements of reactive oxygen species are difficult to obtain in human subjects, thus making this assertion difficult to verify. This investigation suggests the possibility of developing a pharmaceutical therapy to inhibit the sympathoexcitation associated with obstructive sleep apnoea.
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Affiliation(s)
- Noah P Jouett
- Institute for Cardiovascular and Metabolic Disease, University of North Texas Health Science Center, Fort Worth, TX, USA
| | - Gilbert Moralez
- Institute for Cardiovascular and Metabolic Disease, University of North Texas Health Science Center, Fort Worth, TX, USA
| | - Daniel W White
- Integrative Physiology Laboratory, Department of Kinesiology and Nutrition, University of Illinois at Chicago, Chicago, IL, USA
| | - Wendy L Eubank
- Institute for Cardiovascular and Metabolic Disease, University of North Texas Health Science Center, Fort Worth, TX, USA
| | - Shande Chen
- Department of Biostatistics and Epidemiology, University of North Texas Health Science Center, Fort Worth, TX, USA
| | - Jun Tian
- Department of Cellular and Integrative Physiology, University of Nebraska Medical Center, Omaha, NE, USA
| | - Michael L Smith
- Institute for Cardiovascular and Metabolic Disease, University of North Texas Health Science Center, Fort Worth, TX, USA
| | - Matthew C Zimmerman
- Department of Cellular and Integrative Physiology, University of Nebraska Medical Center, Omaha, NE, USA
| | - Peter B Raven
- Institute for Cardiovascular and Metabolic Disease, University of North Texas Health Science Center, Fort Worth, TX, USA
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Bułdak Ł, Łabuzek K, Bułdak RJ, Machnik G, Bołdys A, Basiak M, Bogusław O. Metformin reduces the expression of NADPH oxidase and increases the expression of antioxidative enzymes in human monocytes/macrophages cultured in vitro. Exp Ther Med 2016; 11:1095-1103. [PMID: 26998043 DOI: 10.3892/etm.2016.2977] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2015] [Accepted: 09/25/2015] [Indexed: 01/08/2023] Open
Abstract
The treatment of diabetes and its complications is a key challenge for healthcare professionals. Accelerated atherosclerosis is associated with progressive diabetes, and it has been indicated that macrophages serve a crucial function in this process. Currently, the first-line treatment of diabetes is based on metformin, which is an inducer of AMP-activated protein kinase (AMPK) and belongs to the biguanide class of pharmaceuticals. It has been previously demonstrated that metformin exhibits more than just hypoglycemic effects. Therefore, the aim of the present study was to investigate the in vitro impact of metformin on cell viability and the expression levels of nicotinamide adenine dinucleotide phosphate (NAPDH) oxidase (p22phox), a major enzyme in reactive oxygen species generation, and the three antioxidative enzymes superoxide dismutase (SOD), glutathione peroxidase (GPx) and catalase (CAT) in monocytes/macrophages derived from 10 healthy volunteers. The effects of metformin were observed in the presence or absence of lipopolysaccharide (LPS), which was administered to induce oxidative stress. Furthermore, certain cells were treated with compound C, an inhibitor of AMPK, in order to determine the mechanistic role played by AMPK in the oxidative changes in the macrophages. Cell viability was evaluated using trypan blue and MTT assays. The mRNA and protein expression levels of p22phox and the various antioxidative enzymes were determined using polymerase chain reaction and western blot analysis, respectively. The results indicated that metformin, predominantly in LPS-pretreated monocytes/macrophages, reduced the expression levels of p22phox and increased those of SOD and GPx, but had only a minor effect on CAT levels. Therefore, metformin appears to alter the oxidative status of macrophages toward increasingly antioxidative activity, which may account for the pleiotropic effects observed during metformin treatment.
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Affiliation(s)
- Łukasz Bułdak
- Department of Internal Medicine and Clinical Pharmacology, School of Medicine in Katowice, Medical University of Silesia, Katowice 40-752, Poland
| | - Krzysztof Łabuzek
- Department of Internal Medicine and Clinical Pharmacology, School of Medicine in Katowice, Medical University of Silesia, Katowice 40-752, Poland
| | - Rafał Jakub Bułdak
- Department of Physiology, School of Medicine with the Division of Dentistry in Zabrze, Medical University of Silesia, Zabrze 41-808, Poland
| | - Grzegorz Machnik
- Department of Internal Medicine and Clinical Pharmacology, School of Medicine in Katowice, Medical University of Silesia, Katowice 40-752, Poland
| | - Aleksandra Bołdys
- Department of Internal Medicine and Clinical Pharmacology, School of Medicine in Katowice, Medical University of Silesia, Katowice 40-752, Poland
| | - Marcin Basiak
- Department of Internal Medicine and Clinical Pharmacology, School of Medicine in Katowice, Medical University of Silesia, Katowice 40-752, Poland
| | - Okopień Bogusław
- Department of Internal Medicine and Clinical Pharmacology, School of Medicine in Katowice, Medical University of Silesia, Katowice 40-752, Poland
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Statins and oxidative stress in chronic heart failure. Rev Port Cardiol 2016; 35:41-57. [PMID: 26763895 DOI: 10.1016/j.repc.2015.09.006] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2015] [Accepted: 09/13/2015] [Indexed: 11/23/2022] Open
Abstract
Statins are the most commonly prescribed drugs for the treatment of dyslipidemia. They are also recommended in primary and secondary prevention of cardiovascular disease. In addition to decreasing cholesterol synthesis, statins interfere with the synthesis of isoprenoid intermediates, which may explain many of their pleiotropic properties, including their antioxidant effects. Oxidative stress is defined as an imbalance between the synthesis of reactive oxygen species and their elimination by antioxidant defense systems, with a prevailing pro-oxidant status that results in macromolecular damage and disruption of cellular redox signaling. Reactive oxygen species interfere with various processes that affect cardiac structure and function, contributing to the contractile dysfunction, myocardial hypertrophy and fibrosis observed in the pathophysiology of heart failure. By regulating several molecular pathways that control nicotinamide adenine dinucleotide phosphate oxidase and endothelial nitric oxide synthase activity, statins help restore redox homeostasis. These drugs also contribute to the control of inflammation and appear to have a protective role in various diseases. The results of observational studies and clinical trials with statins in heart failure have not been consensual. This review aims to analyze the role of oxidative stress in heart failure and the molecular mechanisms underlying statins' antioxidant properties. It also examines current scientific evidence on the use of these drugs as a specific treatment for heart failure.
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28
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Statins and oxidative stress in chronic heart failure. REVISTA PORTUGUESA DE CARDIOLOGIA (ENGLISH EDITION) 2016. [DOI: 10.1016/j.repce.2015.12.016] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
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29
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Zhang J, Li Y, Tao GZ, Chen YD, Hu TH, Cao XB, Jing QM, Wang XZ, Ma YY, Wang G, Liu HW, Wang B, Xu K, Li J, Deng J, Han YL. Short-term rosuvastatin treatment for the prevention of contrast-induced acute kidney injury in patients receiving moderate or high volumes of contrast media: a sub-analysis of the TRACK-D study. Chin Med J (Engl) 2015; 128:784-9. [PMID: 25758273 PMCID: PMC4833983 DOI: 10.4103/0366-6999.152620] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022] Open
Abstract
BACKGROUND Current randomized trials have demonstrated the effects of short-term rosuvastatin therapy in preventing contrast-induced acute kidney injury (CIAKI). However, the consistency of these effects on patients administered different volumes of contrast media is unknown. METHODS In the TRACK-D trial, 2998 patients with type 2 diabetes and concomitant chronic kidney disease (CKD) who underwent coronary/peripheral arterial angiography with or without percutaneous intervention were randomized to short-term (2 days before and 3 days after procedure) rosuvastatin therapy or standard-of-care. This prespecified analysis compared the effects of rosuvastatin versus standard therapy in patients exposed to (moderate contrast volume [MCV], 200-300 ml, n = 712) or (high contrast volume [HCV], ≥ 300 ml, n = 220). The primary outcome was the incidence of CIAKI. The secondary outcome was a composite of death, dialysis/hemofiltration or worsened heart failure at 30 days. RESULTS Rosuvastatin treatment was associated with a significant reduction in CIAKI compared with the controls (2.1% vs. 4.4%, P = 0.050) in the overall cohort and in patients with MCV (1.7% vs. 4.5%, P = 0.029), whereas no benefit was observed in patients with HCV (3.4% vs. 3.9%, P = 0.834). The incidence of secondary outcomes was significantly lower in the rosuvastatin group compared with control group (2.7% vs. 5.3%, P = 0.049) in the overall cohort, but it was similar between the patients with MCV (2.0% vs. 4.2%, P = 0.081) or HCV (5.1% vs. 8.8%, P = 0.273). CONCLUSIONS Periprocedural short-term rosuvastatin treatment is effective in reducing CIAKI and adverse clinical events for patients with diabetes and CKD after their exposure to a moderate volume of contrast medium.
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Affiliation(s)
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | - Ya-Ling Han
- Department of Cardiology, General Hospital of Shenyang Military Region, Shenyang, Liaoning 110840, China
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30
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Zucker IH, Schultz HD, Patel KP, Wang H. Modulation of angiotensin II signaling following exercise training in heart failure. Am J Physiol Heart Circ Physiol 2015; 308:H781-91. [PMID: 25681422 PMCID: PMC4398865 DOI: 10.1152/ajpheart.00026.2015] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/15/2015] [Accepted: 02/04/2015] [Indexed: 02/07/2023]
Abstract
Sympathetic activation is a consistent finding in the chronic heart failure (CHF) state. Current therapy for CHF targets the renin-angiotensin II (ANG II) and adrenergic systems. Angiotensin converting enzyme (ACE) inhibitors and ANG II receptor blockers are standard treatments along with β-adrenergic blockade. However, the mortality and morbidity of this disease is still extremely high, even with good medical management. Exercise training (ExT) is currently being used in many centers as an adjunctive therapy for CHF. Clinical studies have shown that ExT is a safe, effective, and inexpensive way to improve quality of life, work capacity, and longevity in patients with CHF. This review discusses the potential neural interactions between ANG II and sympatho-excitation in CHF and the modulation of this interaction by ExT. We briefly review the current understanding of the modulation of the angiotensin type 1 receptor in sympatho-excitatory areas of the brain and in the periphery (i.e., in the carotid body and skeletal muscle). We discuss possible cellular mechanisms by which ExT may impact the sympatho-excitatory process by reducing oxidative stress, increasing nitric oxide. and reducing ANG II. We also discuss the potential role of ACE2 and Ang 1-7 in the sympathetic response to ExT. Fruitful areas of further investigation are the role and mechanisms by which pre-sympathetic neuronal metabolic activity in response to individual bouts of exercise regulate redox mechanisms and discharge at rest in CHF and other sympatho-excitatory states.
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Affiliation(s)
- Irving H Zucker
- Department of Cellular and Integrative Physiology, University of Nebraska Medical Center, Omaha, Nebraska
| | - Harold D Schultz
- Department of Cellular and Integrative Physiology, University of Nebraska Medical Center, Omaha, Nebraska
| | - Kaushik P Patel
- Department of Cellular and Integrative Physiology, University of Nebraska Medical Center, Omaha, Nebraska
| | - Hanjun Wang
- Department of Cellular and Integrative Physiology, University of Nebraska Medical Center, Omaha, Nebraska
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31
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The effect of statins on sympathetic activity: a meta-analysis. Clin Auton Res 2015; 25:125-31. [PMID: 25739473 PMCID: PMC4408357 DOI: 10.1007/s10286-015-0274-1] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2014] [Accepted: 12/29/2014] [Indexed: 01/13/2023]
Abstract
Objective Beyond lipid-lowering properties, statins decrease sympathetic nervous activity. Due to the limited number of studies and included participants, a meta-analysis of randomized, placebo-controlled studies using microneurography (MSNA) was performed to assess sympatholytic effect of statins. Methods We conducted a comprehensive search of online databases (Cochrane, Embase, and EBSCO) for published human studies up to April 2014. Randomized controlled trials (parallel and crossover design) were eligible for inclusion if results of statins versus placebo treatments on sympathetic activity were measured with MSNA. Results Data from five studies with a total number of subjects n = 82 were included into the meta-analysis. MSNA expressed as bursts/min and as bursts/100 heartbeats was lower in the statin group than in the placebo group with a mean difference of −4.37 95 % CI (−7.03; −1.70), p < 0.0013 and −5.85 95 % CI (−7.56; −4.13), p < 0.0001, respectively. No significant publication bias was observed. Meta-regression revealed no significant effect of baseline total cholesterol or dose of statin. No change in blood pressure and heart rate was observed. Conclusions Published data show that regardless of type and dose, statins reduce sympathetic activity measured by microneurography. The role of decreased sympathetic outflow during statin therapy on clinical end points needs to be clarified.
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32
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Vianna LC, Deo SH, Jensen AK, Holwerda SW, Zimmerman MC, Fadel PJ. Impaired dynamic cerebral autoregulation at rest and during isometric exercise in type 2 diabetes patients. Am J Physiol Heart Circ Physiol 2015; 308:H681-7. [PMID: 25599569 DOI: 10.1152/ajpheart.00343.2014] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/20/2014] [Accepted: 01/15/2015] [Indexed: 12/21/2022]
Abstract
Type 2 diabetes mellitus patients (T2D) have elevated risk of stroke, suggesting that cerebrovascular function is impaired. Herein, we examined dynamic cerebral autoregulation (CA) at rest and during exercise in T2D patients and determined whether underlying systemic oxidative stress is associated with impairments in CA. Middle cerebral artery blood velocity and arterial blood pressure (BP) were measured at rest and during 2-min bouts of low- and high-intensity isometric handgrip performed at 20% and 40% maximum voluntary contraction, respectively, in seven normotensive and eight hypertensive T2D patients and eight healthy controls. Dynamic CA was estimated using the rate of regulation (RoR). Total reactive oxygen species (ROS) and superoxide levels were measured at rest. There were no differences in RoR at rest or during exercise between normotensive and hypertensive T2D patients. However, when compared with controls, T2D patients exhibited lower RoR at rest and during low-intensity handgrip indicating impaired dynamic CA. Moreover, the RoR was further reduced by 29 ± 4% during high-intensity handgrip in T2D patients (0.307 ± 0.012/s rest vs. 0.220 ± 0.014/s high intensity; P < 0.01), although well maintained in controls. T2D patients demonstrated greater baseline total ROS and superoxide compared with controls, both of which were negatively related to RoR during handgrip (e.g., total ROS: r = -0.71, P < 0.05; 40% maximum voluntary contraction). Collectively, these data demonstrate impaired dynamic CA at rest and during isometric handgrip in T2D patients, which may be, in part, related to greater underlying systemic oxidative stress. Additionally, dynamic CA is blunted further with high intensity isometric contractions potentially placing T2D patients at greater risk for cerebral events during such activities.
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Affiliation(s)
- Lauro C Vianna
- Faculty of Physical Education, University of Brasília, DF, Brazil; Department of Medical Pharmacology and Physiology, University of Missouri, Columbia, Missouri
| | - Shekhar H Deo
- Department of Medical Pharmacology and Physiology, University of Missouri, Columbia, Missouri
| | - Areum K Jensen
- Department of Medical Pharmacology and Physiology, University of Missouri, Columbia, Missouri
| | - Seth W Holwerda
- Department of Medical Pharmacology and Physiology, University of Missouri, Columbia, Missouri
| | - Matthew C Zimmerman
- Department of Cellular and Integrative Physiology, University of Nebraska Medical Center, Omaha, Nebraska
| | - Paul J Fadel
- Department of Medical Pharmacology and Physiology, University of Missouri, Columbia, Missouri; Dalton Cardiovascular Research Center, University of Missouri, Columbia, Missouri; and
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Schultz HD, Marcus NJ, Del Rio R. Mechanisms of carotid body chemoreflex dysfunction during heart failure. Exp Physiol 2015; 100:124-9. [PMID: 25398713 DOI: 10.1113/expphysiol.2014.079517] [Citation(s) in RCA: 53] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2014] [Accepted: 11/03/2014] [Indexed: 11/08/2022]
Abstract
NEW FINDINGS What is the topic of this review? Carotid body chemoreceptor activity is tonically elevated in heart failure and contributes to morbidity due to the reflex activation of sympathetic nerve activity and destabilization of breathing. The potential causes for the enhanced chemoreceptor activation in heart failure are discussed. What advances does it highlight? The role of a chronic reduction in blood flow to the carotid body due to cardiac failure and its impact on signalling pathways in the carotid body is discussed. Recent advances have attracted interest in the potential for carotid body (CB) ablation or desensitization as an effective strategy for clinical treatment and management of cardiorespiratory diseases, including hypertension, heart failure, diabetes mellitus, metabolic syndrome and renal failure. These disease states have in common sympathetic overactivity, which plays an important role in the development and progression of the disease and is often associated with breathing dysregulation, which in turn is likely to mediate or aggravate the autonomic imbalance. Evidence from both chronic heart failure (CHF) patients and animal models indicates that the CB chemoreflex is enhanced in CHF and contributes to the tonic elevation in sympathetic activity and the development of periodic breathing associated with the disease. Although this maladaptive change is likely to derive from altered function at all levels of the reflex arc, a tonic increase in afferent activity from CB glomus cells is likely to be a main driving force. This report focuses on our understanding of mechanisms that alter CB function in CHF and their potential translational impact on treatment of CHF.
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Affiliation(s)
- Harold D Schultz
- Department of Cellular and Integrative Physiology, University of Nebraska Medical Center, Omaha, NE, USA
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Role of the Carotid Body Chemoreflex in the Pathophysiology of Heart Failure: A Perspective from Animal Studies. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2015; 860:167-85. [PMID: 26303479 DOI: 10.1007/978-3-319-18440-1_19] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
The treatment and management of chronic heart failure (CHF) remains an important focus for new and more effective clinical strategies. This important goal, however, is dependent upon advancing our understanding of the underlying pathophysiology. In CHF, sympathetic overactivity plays an important role in the development and progression of the cardiac and renal dysfunction and is often associated with breathing dysregulation, which in turn likely mediates or aggravates the autonomic imbalance. In this review we will summarize evidence that in CHF, the elevation in sympathetic activity and breathing instability that ultimately lead to cardiac and renal failure are driven, at least in part, by maladaptive activation of the carotid body (CB) chemoreflex. This maladaptive change derives from a tonic increase in CB afferent activity. We will focus our discussion on an understanding of mechanisms that alter CB afferent activity in CHF and its consequence on reflex control of autonomic, respiratory, renal, and cardiac function in animal models of CHF. We will also discuss the potential translational impact of targeting the CB in the treatment of CHF in humans, with relevance to other cardio-respiratory diseases.
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De Raedt S, De Vos A, De Keyser J. Autonomic dysfunction in acute ischemic stroke: an underexplored therapeutic area? J Neurol Sci 2014; 348:24-34. [PMID: 25541326 DOI: 10.1016/j.jns.2014.12.007] [Citation(s) in RCA: 67] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2014] [Revised: 11/30/2014] [Accepted: 12/02/2014] [Indexed: 01/04/2023]
Abstract
Impaired autonomic function, characterized by a predominance of sympathetic activity, is common in patients with acute ischemic stroke. This review describes methods to measure autonomic dysfunction in stroke patients. It summarizes a potential relationship between ischemic stroke-associated autonomic dysfunction and factors that have been associated with worse outcome, including cardiac complications, blood pressure variability changes, hyperglycemia, immune depression, sleep disordered breathing, thrombotic effects, and malignant edema. Involvement of the insular cortex has been suspected to play an important role in causing sympathovagal imbalance, but its exact role and that of other brain regions remain unclear. Although sympathetic overactivity in patients with ischemic stroke appears to be a negative prognostic factor, it remains to be seen whether therapeutic strategies that reduce sympathetic activity or increase parasympathetic activity might improve outcome.
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Affiliation(s)
- Sylvie De Raedt
- Department of Neurology, Universitair Ziekenhuis Brussel, Center for Neurosciences, Vrije Universiteit Brussel (VUB), Brussels, Belgium.
| | - Aurelie De Vos
- Department of Neurology, Universitair Ziekenhuis Brussel, Center for Neurosciences, Vrije Universiteit Brussel (VUB), Brussels, Belgium.
| | - Jacques De Keyser
- Department of Neurology, Universitair Ziekenhuis Brussel, Center for Neurosciences, Vrije Universiteit Brussel (VUB), Brussels, Belgium; Department of Neurology, Universitair Medisch Centrum Groningen, Groningen, The Netherlands.
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Fernandes IA, Vianna LC, Freitas RA, Miranda SM, Mesquita ET, Mesquita CT, da Nóbrega ACL. Statin therapy and cardiac sympathetic activity in patients with heart failure: A 123Iodine-metaiodobenzylguanidine myocardial scintigraphy study. Int J Cardiol 2014; 176:1181-3. [DOI: 10.1016/j.ijcard.2014.07.243] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/22/2014] [Accepted: 07/27/2014] [Indexed: 01/08/2023]
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Koba S, Hisatome I, Watanabe T. Central command dysfunction in rats with heart failure is mediated by brain oxidative stress and normalized by exercise training. J Physiol 2014; 592:3917-31. [PMID: 24973409 DOI: 10.1113/jphysiol.2014.272377] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
Sympathoexcitation elicited by central command, a parallel activation of the motor and autonomic neural circuits in the brain, has been shown to become exaggerated in chronic heart failure (CHF). The present study tested the hypotheses that oxidative stress in the medulla in CHF plays a role in exaggerating central command-elicited sympathoexcitation, and that exercise training in CHF suppresses central command-elicited sympathoexcitation through its antioxidant effects in the medulla. In decerebrate rats, central command was activated by electrically stimulating the mesencephalic locomotor region (MLR) after neuromuscular blockade. The MLR stimulation at a current intensity greater than locomotion threshold in rats with CHF after myocardial infarction (MI) evoked larger (P < 0.05) increases in renal sympathetic nerve activity and arterial pressure than in sham-operated healthy rats (Sham) and rats with CHF that had completed longterm (8–12 weeks) exercise training (MI + TR). In the Sham and MI + TR rats, bilateral microinjection of a superoxide dismutase (SOD) mimetic Tempol into the rostral ventrolateral medulla (RVLM) had no effects on MLR stimulation-elicited responses. By contrast, in MI rats, Tempol treatment significantly reduced MLR stimulation-elicited responses. In a subset of MI rats, treatment with Tiron, another SOD mimetic, within the RVLM also reduced responses. Superoxide generation in the RVLM, as evaluated by dihydroethidium staining, was enhanced in MI rats compared with that in Sham and MI + TR rats. Collectively, these results support the study hypotheses. We suggest that oxidative stress in the medulla in CHF mediates central command dysfunction, and that exercise training in CHF is capable of normalizing central command dysfunction through its antioxidant effects in the medulla.
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Affiliation(s)
- Satoshi Koba
- Division of Integrative Physiology, Faculty of Medicine, Tottori University, Yonago, Japan
| | - Ichiro Hisatome
- Division of Regenerative Medicine and Therapeutics, Graduate School of Medical Science, Tottori University, Yonago, Japan
| | - Tatsuo Watanabe
- Division of Integrative Physiology, Faculty of Medicine, Tottori University, Yonago, Japan
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Simvastatin but not ezetimibe reduces sympathetic activity despite similar reductions in cholesterol levels. ACTA ACUST UNITED AC 2014; 8:715-23. [PMID: 25418493 DOI: 10.1016/j.jash.2014.06.003] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2014] [Revised: 06/12/2014] [Accepted: 06/19/2014] [Indexed: 11/20/2022]
Abstract
The relationship between the sympatholytic effects of statins and their lipid-lowering activity remains unclear. Ezetimibe lowers cholesterol, but its sympatholytic activity is unknown. The purpose of study was to compare the influence of equipotent doses of simvastatin and ezetimibe on sympathetic activity. This randomized double-blinded study was performed in 22 hypertensive patients (age, 45.6 ± 2.2 years; female/male, 2/20) with untreated hypercholesterolemia. The subjects were administered 20 mg/d of simvastatin (n = 11) or 20 mg/d of ezetimibe (n = 11) for 6 weeks. Pre- and post-treatment measurements of muscle sympathetic nerve activity (MSNA), baroreceptor control of heart rate (baroreflex sensitivity), and impedance cardiography were recorded. Simvastatin and ezetimibe produced similar reductions of total (-58.0 ± 23.4 vs. -45.2 ± 17.2 mg/dL; P = .15, respectively) and low-density lipoprotein cholesterol (-52.6 ± 20.9 vs. -37.9 ± 17.6 mg/dL; P = .09, respectively). There was a significant difference in the effect of simvastatin and ezetimibe on muscle sympathetic nerve activity (-8.5 ± 5.1 vs. -0.7 ± 3.5 bursts/min; P = .0005). Simvastatin improved baroreflex sensitivity as compared with ezetimibe (10.0 ± 14.3 vs. -2.8 ± 6.1 ms/mm Hg; P = .01). There was no difference in the effect of both treatments on blood pressure, heart rate, cardiac output, stroke volume, total peripheral resistance, high-density lipoprotein, and triglycerides. Simvastatin reduced sympathetic activity via lipid-independent mechanisms, but ezetimibe exerts no sympatholytic effects.
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Haack KKV, Marcus NJ, Del Rio R, Zucker IH, Schultz HD. Simvastatin treatment attenuates increased respiratory variability and apnea/hypopnea index in rats with chronic heart failure. Hypertension 2014; 63:1041-9. [PMID: 24516105 DOI: 10.1161/hypertensionaha.113.02535] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Cheyne-Stokes respiration and cardiac arrhythmias are associated with increased morbidity and mortality in patients with chronic heart failure (CHF). Enhanced carotid body chemoreflex (CBC) sensitivity is associated with these abnormalities in CHF. Reduced carotid body (CB) nitric oxide and nitric oxide synthase (NOS) levels play an important role in the enhanced CBC. In other disease models, Simvastatin (statin) treatment increases endothelial NOS, in part, by increasing Krüppel-like Factor 2 expression. We hypothesized that statin treatment would ameliorate enhanced CBC sensitivity as well as increased respiratory variability, apnea/hypopnea index, and arrhythmia index, in a rodent model of CHF. Resting breathing pattern, cardiac rhythm, and the ventilatory and CB chemoreceptor afferent responses to hypoxia were assessed in rats with CHF induced by coronary ligation. CHF was associated with enhanced ventilatory and CB afferent responses to hypoxia as well as increased respiratory variability, apnea/hypopnea index, and arrhythmia index. Statin treatment prevented the increases in CBC sensitivity and the concomitant increases in respiratory variability, apnea/hypopnea index, and arrhythmia index. Krüppel-like Factor 2 and endothelial NOS protein were decreased in the CB and nucleus tractus solitarii of CHF animals, and statin treatment increased the expression of these proteins. Our findings demonstrate that the increased CBC sensitivity, respiratory instability, and cardiac arrhythmias observed in CHF are ameliorated by statin treatment and suggest that statins may be an effective treatment for Cheyne-Stokes respiration and arrhythmias in patient populations with high chemoreflex sensitivity.
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Affiliation(s)
- Karla K V Haack
- Department of Cellular and Integrative Physiology, 985850 Nebraska Medical Center, Omaha, NE 68198.
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Dey A, Lakshmanan J. The role of antioxidants and other agents in alleviating hyperglycemia mediated oxidative stress and injury in liver. Food Funct 2014; 4:1148-84. [PMID: 23760593 DOI: 10.1039/c3fo30317a] [Citation(s) in RCA: 82] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Several antioxidants and agents having similar antioxidant effects are known to exert beneficial effects in ameliorating the injurious effects of hyperglycemia on liver in different diabetic in vitro and in vivo models. The review deals with some of the agents which have been shown to exert protective effects on liver against hyperglycemic insult and the various mechanisms involved. The different classes of agents which protect the diabetic liver or decrease the severity of hyperglycemia mediated injury include flavonoids, catechins, and other polyphenolic compounds, curcumin and its derivatives, certain vitamins, hormones and drugs, trace elements, prototypical antioxidants and amino acids. Some of the pronounced changes mediated by the antioxidants in liver exposed to hyperglycemia include decreased oxidative stress, and alterations in carbohydrate and lipid metabolism. Other mechanisms through which the agents ameliorate hyperglycemia mediated liver injury include decrease in oxidative DNA and protein damage, restoration of mitochondrial structural and functional integrity, decrease in inflammation and improved insulin signaling. Thus, antioxidants may prove to be an important mode of defense in maintaining normal hepatic functions in diabetes.
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Affiliation(s)
- Aparajita Dey
- Life Science Division, AU-KBC Research Centre, MIT Campus of Anna University, Chromepet, Chennai 600044, India.
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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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Han Y, Zhu G, Han L, Hou F, Huang W, Liu H, Gan J, Jiang T, Li X, Wang W, Ding S, Jia S, Shen W, Wang D, Sun L, Qiu J, Wang X, Li Y, Deng J, Li J, Xu K, Xu B, Mehran R, Huo Y. Short-term rosuvastatin therapy for prevention of contrast-induced acute kidney injury in patients with diabetes and chronic kidney disease. J Am Coll Cardiol 2013; 63:62-70. [PMID: 24076297 DOI: 10.1016/j.jacc.2013.09.017] [Citation(s) in RCA: 135] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/15/2013] [Revised: 09/03/2013] [Accepted: 09/05/2013] [Indexed: 10/26/2022]
Abstract
OBJECTIVES This study sought to evaluate the safety and efficacy of rosuvastatin in preventing contrast-induced acute kidney injury (CI-AKI) in patients with diabetes mellitus (DM) and chronic kidney disease (CKD). BACKGROUND CI-AKI is an important complication after contrast medium injection. While small studies have shown positive results with statin therapy, the role of statin therapy in prevention of CI-AKI remains unknown. METHODS We randomized 2,998 patients with type 2 DM and concomitant CKD who were undergoing coronary/peripheral arterial angiography with or without percutaneous intervention to receive rosuvastatin, 10 mg/day (n = 1,498), for 5 days (2 days before, and 3 days after procedure) or standard-of-care (n = 1,500). Patients' renal function was assessed at baseline, 48 h, and 72 h after exposure to contrast medium. The primary endpoint of the study was the development of CI-AKI, which was defined as an increase in serum creatinine concentration ≥0.5 mg/dl (44.2 μmol/l) or 0.25% above baseline at 72 h after exposure to contrast medium. RESULTS Patients randomized to the rosuvastatin group had a significantly lower incidence of CI-AKI than controls (2.3% vs. 3.9%, respectively; p = 0.01). During 30 days' follow-up, the rate of worsening heart failure was significantly lower in the patients treated with rosuvastatin than that in the control group (2.6% vs. 4.3%, respectively; p = 0.02). CONCLUSIONS Rosuvastatin significantly reduced the risk of CI-AKI in patients with DM and CKD undergoing arterial contrast medium injection. (Rosuvastatin Prevent Contrast Induced Acute Kidney Injury in Patients With Diabetes [TRACK-D]; NCT00786136).
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Affiliation(s)
- Yaling Han
- Department of Cardiology, Shenyang Northern Hospital, Shenyang, China.
| | - Guoying Zhu
- Department of Cardiology, WuHan Asia Heart Hospital, Wuhan, China
| | - Lixian Han
- Department of Cardiology, CangZhou Central Hospital, CangZhou, China
| | - Fengxia Hou
- Department of Cardiology, Changchun Central Hospital, Changchun, China
| | - Weijian Huang
- Department of Cardiology, The First Affiliated Hospital of Wenzhou Medical College, Wenzhou, China
| | - Huiliang Liu
- Department of Cardiology, General Hospital of Armed Police Forces, Beijing, China
| | - Jihong Gan
- Department of Cardiology, Lanzhou Military WuluMuqi PLA Hospital, Wulumuqi, China
| | - Tiemin Jiang
- Department of Cardiology, Affiliated Hospital of Medical College of Armed Police Forces, Tianjin, China
| | - Xiaoyan Li
- Department of Cardiology, Jinan Military General Hospital, Jinan, China
| | - Wei Wang
- Department of Cardiology, The First Affiliated Hospital of Guangzhou Medical University, Guangzhou, China
| | - Shifang Ding
- Department of Cardiology, Wuhan General Hospital of Guangzhou Military, Wuhan, China
| | - Shaobin Jia
- Department of Cardiology, Affiliated Hospital of Ningxia Medical College, Yinchuan, China
| | - Weifeng Shen
- Department of Cardiology, Ruijin Hospital Affiliated to the Medical College of Shanghai Jiaotong University, Shanghai, China
| | - Dongmei Wang
- Department of Cardiology, Shijiazhuang International Peace Hospital, Shijiazhuang, China
| | - Ling Sun
- Department of Cardiology, Fushun Central Hospital, Fushun, China
| | - Jian Qiu
- Department of Cardiology, General Hospital of Guangzhou Military Command of PLA, Guangzhou, China
| | - Xiaozeng Wang
- Department of Cardiology, Shenyang Northern Hospital, Shenyang, China
| | - Yi Li
- Department of Cardiology, Shenyang Northern Hospital, Shenyang, China
| | - Jie Deng
- Department of Cardiology, Shenyang Northern Hospital, Shenyang, China
| | - Jing Li
- Department of Cardiology, Shenyang Northern Hospital, Shenyang, China
| | - Kai Xu
- Department of Cardiology, Shenyang Northern Hospital, Shenyang, China
| | - Bo Xu
- Cardiac Catheterization Laboratory, Fuwai Hospital, Beijing, China
| | - Roxana Mehran
- Zena and Michael A. Weiner Cardiovascular Institute, Icahn School of Medicine at Mount Sinai, New York, New York
| | - Yong Huo
- Department of Cardiology, First Hospital of Beijing University, Beijing, China
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Deo SH, Jenkins NT, Padilla J, Parrish AR, Fadel PJ. Norepinephrine increases NADPH oxidase-derived superoxide in human peripheral blood mononuclear cells via α-adrenergic receptors. Am J Physiol Regul Integr Comp Physiol 2013; 305:R1124-32. [PMID: 24068047 DOI: 10.1152/ajpregu.00347.2013] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Many diseases associated with sympathoexcitation also exhibit elevated reactive oxygen species (ROS). A recent animal study indicated that exogenous administration of the sympathetic neurotransmitter norepinephrine (NE) increased systemic ROS via circulating leukocytes. The mechanisms contributing to this effect of NE and whether these findings can be translated to humans is unknown. Thus we tested the hypothesis that NE increases superoxide production in human peripheral blood mononuclear cells (PBMCs) via NADPH oxidase. Primary human PBMCs were freshly isolated from healthy young men and placed in culture. After NE (50 pg/ml, 50 ng/ml, and 50 μg/ml concentrations) or control treatments, NADPH oxidase mRNA expression (gp91(phox), p22(phox), and p67(phox)) was assessed using real-time RT-PCR, and intracellular superoxide production was measured using dihydroethidium fluorescence. PBMCs were also treated with selective adrenergic agonists-antagonists to determine the receptor population involved. In addition, CD14(+) monocyte-endothelial cell adhesion was determined using a fluorescent-based assay. NE significantly increased NADPH oxidase gene expression and intracellular superoxide production in a time-dependent manner (superoxide: 0.9 ± 0.2 fold, 6 h vs. 3.0 ± 0.3 fold, 36 h; NE, 50 μg/ml; P < 0.05). The sustained increase in NE-induced superoxide production was primarily mediated via α-adrenergic receptors, preferentially α2-receptors. The NADPH oxidase blocker diphenylene iodonium and protein kinase C inhibitor Staurosporine significantly attenuated NE-induced increases in superoxide production. Importantly, NE treatment increased CD14(+) monocyte-endothelial cell adhesion. These findings indicate for the first time that NE increases superoxide production in freshly isolated primary human PBMCs via NADPH oxidase through α-adrenergic receptors, an effect facilitating monocyte adhesion to the endothelium.
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Affiliation(s)
- Shekhar H Deo
- Department of Medical Pharmacology and Physiology, University of Missouri, Columbia, Missouri
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Moreira ED, Mostarda CT, Moraes-Silva IC, Ferreira JB, Dos Santos F, Lacchini S, De Angelis K, Rodrigues B, Irigoyen MC. Effect of simvastatin in the autonomic system is dependent on the increased gain/sensitivity of the baroreceptors. Physiol Rep 2013; 1:e00045. [PMID: 24303130 PMCID: PMC3835001 DOI: 10.1002/phy2.45] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2013] [Revised: 07/03/2013] [Accepted: 07/04/2013] [Indexed: 12/12/2022] Open
Abstract
A number of mechanisms have been proposed to explain the pleiotropic effect of statin therapy to reduce sympathetic outflow in cardiovascular disease. We tested the hypothesis that statin treatment could improve baroreflex gain-sensitivity triggered by morphological adaptations in the mechanoreceptor site, thus reducing sympathetic activity, regardless of arterial pressure (AP) level reduction. Male spontaneously hypertensive rats (SHR) were divided into control (SHR, n = 8) and SHR-simvastatin (5 mg/kg/day, for 7 days) (SHR-S, n = 8). After treatment, AP, baroreflex sensitivity (BRS) in response to AP-induced changes, aortic depressor nerve activity, and spectral analyses of pulse interval (PI) and AP variabilities were performed. Internal and external carotids were prepared for morphoquantitative evaluation. Although AP was similar between groups, sympathetic modulation, represented by the low frequency band of PI (SHR: 6.84 ± 3.19 vs. SHR-S: 2.41 ± 0.96 msec2) and from systolic AP variability (SHR: 3.95 ± 0.36 vs. SHR-S: 2.86 ± 0.18 mmHg2), were reduced in treated animals. In parallel, simvastatin induced an increase of 26% and 21% in the number of elastic lamellae as well as a decrease of 9% and 25% in the carotid thickness in both, external and internal carotid, respectively. Moreover, improved baroreceptor function (SHR: 0.78 ± 0.03 vs. SHR-S: 1.06 ± 0.04% mv/mmHg) was observed in addition to a 115% increase in aortic depressor nerve activity in SHR-S rats. Therefore, our data suggest that the reduction of sympathetic outflow in hypertension by simvastatin treatment may be triggered by structural changes in the carotid arteries and increased BRS in response to an improvement of the baroreceptors discharge and consequently of the afferent pathway of the baroreflex arch.
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Affiliation(s)
- Edson D Moreira
- Experimental Hypertension Laboratory, Heart Institute (InCor), University of Sao Paulo Medical School Sao Paulo, Brazil
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Fouad AA, Albuali WH, Jresat I. Simvastatin treatment ameliorates injury of rat testes induced by cadmium toxicity. Biol Trace Elem Res 2013; 153:269-78. [PMID: 23625729 DOI: 10.1007/s12011-013-9667-y] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/26/2013] [Accepted: 04/08/2013] [Indexed: 10/26/2022]
Abstract
Cadmium-induced testicular toxicity is mediated through oxidative stress and inflammation which eventually lead to cell death. Simvastatin, the antihyperlipidemic agent, exhibits additional antioxidant and anti-inflammatory activities. The aim of the present work was to investigate the protective effect of simvastatin against cadmium-induced testicular toxicity in rats. The rats received a single intraperitoneal (i.p.) injection of cadmium chloride (2 mg/kg). Simvastatin treatment (5 mg/kg/day, i.p.) was applied for three consecutive days, starting 1 day before cadmium administration. Cadmium significantly decreased serum testosterone, and testicular reduced glutathione and catalase activity, and significantly increased testicular malondialdehyde, nitric oxide, and cadmium ion levels. Simvastatin significantly ameliorated the biochemical changes induced by cadmium. Cadmium-induced testicular tissue injury observed by histopathological examination was attenuated by simvastatin. In addition, simvastatin significantly decreased the expression of inducible nitric oxide synthase, cyclooxygenase-2, tumor necrosis factor-α, nuclear factor-κB, and caspase-3, and increased heme oxygenase-1 expression in testicular tissue of rats exposed to cadmium toxicity. It was concluded that simvastatin, through its antioxidant and anti-inflammatory activities, provided a significant protective effect against cadmium-induced testicular toxicity in rats. However, starting treatment with simvastatin before cadmium exposure, as done in the present work, is not clinically applicable. Therefore, other investigations are needed to assess the protective effect of simvastatin treatment following induction of cadmium testicular toxicity.
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Affiliation(s)
- Amr A Fouad
- Department of Biomedical Sciences, Pharmacology Division, College of Medicine, King Faisal University, Al-Ahsa, 31982 Saudi Arabia.
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Rubinger D, Backenroth R, Sapoznikov D. Sympathetic Nervous System Function and Dysfunction in Chronic Hemodialysis Patients. Semin Dial 2013; 26:333-43. [DOI: 10.1111/sdi.12093] [Citation(s) in RCA: 62] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Affiliation(s)
- Dvora Rubinger
- Nephrology and Hypertension Services; Hadassah University; Medical Center; Jerusalem; Israel
| | - Rebecca Backenroth
- Nephrology and Hypertension Services; Hadassah University; Medical Center; Jerusalem; Israel
| | - Dan Sapoznikov
- Nephrology and Hypertension Services; Hadassah University; Medical Center; Jerusalem; Israel
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Haack KKV, Gao L, Schiller AM, Curry PL, Pellegrino PR, Zucker IH. Central Rho kinase inhibition restores baroreflex sensitivity and angiotensin II type 1 receptor protein imbalance in conscious rabbits with chronic heart failure. Hypertension 2013; 61:723-9. [PMID: 23283363 DOI: 10.1161/hypertensionaha.111.00396] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
The small GTPase RhoA and its associated kinase ROCKII are involved in vascular smooth muscle cell contraction and endothelial NO synthase mRNA destabilization. Overactivation of the RhoA/ROCKII pathway is implicated in several pathologies, including chronic heart failure (CHF), and may contribute to the enhanced sympathetic outflow seen in CHF as a result of decreased NO availability. Thus, we hypothesized that central ROCKII blockade would improve the sympathovagal imbalance in a pacing rabbit model of CHF in an NO-dependent manner. CHF was induced by rapid ventricular pacing and characterized by an ejection fraction of ≤45%. Animals were implanted with an intracerbroventricular cannula and osmotic minipump (rate, 1 μL/h) containing sterile saline, 1.5 µg/kg per day fasudil (Fas, a ROCKII inhibitor) for 4 days or Fas+100 µg/kg per day Nω-Nitro-l-arginine methyl ester hydrochloride, a NO synthase inhibitor. Arterial baroreflex control was assessed by intravenous infusion of sodium nitroprusside and phenylephrine. Fas infusion significantly lowered resting heart rate by decreasing sympathetic and increasing vagal tone. Furthermore, Fas improved baroreflex gain in CHF in an NO-dependent manner. In CHF Fas animals, the decrease in heart rate in response to intravenous metoprolol was similar to Sham and was reversed by Nω-Nitro-l-arginine methyl ester hydrochloride. Fas decreased angiotensin II type 1 receptor and phospho-ERM protein expression and increased endothelial NO synthase expression in the brain stem of CHF animals. These data strongly suggest that central ROCKII activation contributes to cardiac sympathoexcitation in the setting of CHF and that central Fas restores vagal and sympathetic tone in an NO-dependent manner. ROCKII may be a new central therapeutic target in the setting of CHF.
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