1
|
Guevara A, Smith CER, Caldwell JL, Ngo L, Mott LR, Lee IJ, Tapa S, Wang Z, Wang L, Woodward WR, Ng GA, Habecker BA, Ripplinger CM. Chronic nicotine exposure is associated with electrophysiological and sympathetic remodeling in the intact rabbit heart. Am J Physiol Heart Circ Physiol 2024. [PMID: 38551482 DOI: 10.1152/ajpheart.00749.2023] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/28/2023] [Accepted: 03/27/2024] [Indexed: 04/09/2024]
Abstract
Nicotine is the primary addictive component in tobacco products. Through its actions on the heart and autonomic nervous system, nicotine exposure is associated with electrophysiological changes and increased arrhythmia susceptibility. To assess underlying mechanisms, we treated rabbits with transdermal nicotine (NIC, 21 mg/day) or control (CT) patches for 28 days prior to performing dual optical mapping of transmembrane potential (RH237) and intracellular Ca2+ (Rhod-2 AM) in isolated hearts with intact sympathetic innervation. Sympathetic nerve stimulation (SNS) was performed at the 1st - 3rd thoracic vertebrae, and β-adrenergic responsiveness was additionally evaluated following norepinephrine (NE) perfusion. Baseline ex vivo HR and SNS stimulation threshold were higher in NIC vs. CT (P = 0.004 and P = 0.003, respectively). Action potential duration alternans emerged at longer pacing cycle lengths (PCL) in NIC vs. CT at baseline (P = 0.002) and during SNS (P = 0.0003), with similar results obtained for Ca2+ transient alternans. SNS shortened the PCL at which alternans emerged in CT but not NIC hearts. NIC exposed hearts tended to have slower and reduced HR responses to NE perfusion, but ventricular responses to NE were comparable between groups. While fibrosis was unaltered, NIC hearts had lower sympathetic nerve density (P = 0.03) but no difference in NE content vs. CT. These results suggest both sympathetic hypo-innervation of the myocardium and regional differences in β-adrenergic responsiveness with NIC. This autonomic remodeling may contribute to the increased risk of arrhythmias associated with nicotine exposure, which may be further exacerbated with long-term use.
Collapse
Affiliation(s)
- Amanda Guevara
- Pharmacology, University of California, Davis, Davis, California, United States
| | | | | | - Lena Ngo
- Pharmacology, University of California, Davis, United States
| | - Lilian R Mott
- Pharmacology, University of California, Davis, Davis, CA, United States
| | - I-Ju Lee
- Pharmacology, University of California, Davis, United States
| | - Srinivas Tapa
- Pharmacology, University of California, Davis, Davis, CA, United States
| | - Zhen Wang
- Shantou University Medical College, Shantou, Guangdong, China
| | - Lianguo Wang
- Pharmacology, University of California, Davis, Davis, CA, United States
| | - William R Woodward
- Neurology, Oregon Health & Science University, Portland, Oregon, United States
| | | | - Beth A Habecker
- Chemical Physiology & Biochemistry, Oregon Health and Science University, Portland, Oregon, United States
| | | |
Collapse
|
2
|
Diba P, Sattler AL, Korzun T, Habecker BA, Marks DL. Unraveling the lost balance: Adrenergic dysfunction in cancer cachexia. Auton Neurosci 2024; 251:103136. [PMID: 38071925 PMCID: PMC10883135 DOI: 10.1016/j.autneu.2023.103136] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2023] [Revised: 11/05/2023] [Accepted: 11/30/2023] [Indexed: 01/23/2024]
Abstract
Cancer cachexia, characterized by muscle wasting and widespread inflammation, poses a significant challenge for patients with cancer, profoundly impacting both their quality of life and treatment management. However, existing treatment modalities remain very limited, accentuating the necessity for innovative therapeutic interventions. Many recent studies demonstrated that changes in autonomic balance is a key driver of cancer cachexia. This review consolidates research findings from investigations into autonomic dysfunction across cancer cachexia, spanning animal models and patient cohorts. Moreover, we explore therapeutic strategies involving adrenergic receptor modulation through receptor blockers and agonists. Mechanisms underlying adrenergic hyperactivity in cardiac and adipose tissues, influencing tissue remodeling, are also examined. Looking ahead, we present a perspective for future research that delves into autonomic dysregulation in cancer cachexia. This comprehensive review highlights the urgency of advancing research to unveil innovative avenues for combatting cancer cachexia and improving patient well-being.
Collapse
Affiliation(s)
- Parham Diba
- Medical Scientist Training Program, Oregon Health & Science University, 3181 SW Sam Jackson Park Road, Portland, OR 97239, USA; Papé Family Pediatric Research Institute, Oregon Health & Science University, SW Sam Jackson Park Rd, Mail Code L481 Portland, OR 97239, USA
| | - Ariana L Sattler
- Papé Family Pediatric Research Institute, Oregon Health & Science University, SW Sam Jackson Park Rd, Mail Code L481 Portland, OR 97239, USA; Knight Cancer Institute, Oregon Health & Science University, 2720 S Moody Avenue, Portland, OR 97201, USA; Brenden-Colson Center for Pancreatic Care, Oregon Health & Science University, 2730 S Moody Avenue, Portland, OR 97201, USA
| | - Tetiana Korzun
- Medical Scientist Training Program, Oregon Health & Science University, 3181 SW Sam Jackson Park Road, Portland, OR 97239, USA; Papé Family Pediatric Research Institute, Oregon Health & Science University, SW Sam Jackson Park Rd, Mail Code L481 Portland, OR 97239, USA
| | - Beth A Habecker
- Department of Chemical Physiology and Biochemistry, Oregon Health and Science University, Portland, OR 97239, USA; Department of Medicine, Knight Cardiovascular Institute, Oregon Health and Science University, Portland, OR 97239, USA
| | - Daniel L Marks
- Papé Family Pediatric Research Institute, Oregon Health & Science University, SW Sam Jackson Park Rd, Mail Code L481 Portland, OR 97239, USA; Knight Cancer Institute, Oregon Health & Science University, 2720 S Moody Avenue, Portland, OR 97201, USA; Brenden-Colson Center for Pancreatic Care, Oregon Health & Science University, 2730 S Moody Avenue, Portland, OR 97201, USA.
| |
Collapse
|
3
|
Habecker BA. Identifying vagal sensory neurons driving the Bezold-Jarisch reflex. Trends Neurosci 2024; 47:90-91. [PMID: 38030510 PMCID: PMC10922441 DOI: 10.1016/j.tins.2023.11.007] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2023] [Accepted: 11/22/2023] [Indexed: 12/01/2023]
Abstract
Homeostatic reflexes are crucial for life, but the subpopulations of sensory neurons that stimulate these reflexes are largely unknown. A recent paper from Lovelace, Ma, and colleagues identified a population of sensory neurons in the cardiac ventricle that underlies the Bezold-Jarisch reflex and triggers syncope (fainting).
Collapse
Affiliation(s)
- Beth A Habecker
- Department of Chemical Physiology and Biochemistry, Oregon Health & Science University, Portland, OR 97239, USA; Department of Medicine, Knight Cardiovascular Institute, Oregon Health & Science University, Portland, OR 97239, USA.
| |
Collapse
|
4
|
Barrett MS, Bauer TC, Li MH, Hegarty DM, Mota CMD, Amaefuna CJ, Ingram SL, Habecker BA, Aicher SA. Ischemia-reperfusion myocardial infarction induces remodeling of left cardiac-projecting stellate ganglia neurons. Am J Physiol Heart Circ Physiol 2024; 326:H166-H179. [PMID: 37947434 DOI: 10.1152/ajpheart.00582.2023] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/19/2023] [Revised: 10/23/2023] [Accepted: 11/08/2023] [Indexed: 11/12/2023]
Abstract
Neurons in the stellate ganglion (SG) provide sympathetic innervation to the heart, brown adipose tissue (BAT), and other organs. Sympathetic innervation to the heart becomes hyperactive following myocardial infarction (MI). The impact of MI on the morphology of cardiac sympathetic neurons is not known, but we hypothesized that MI would stimulate increased cell and dendritic tree size in cardiac neurons. In this study, we examined the effects of ischemia-reperfusion MI on sympathetic neurons using dual retrograde tracing methods to allow detailed characterization of cardiac- and BAT-projecting neurons. Different fluorescently conjugated cholera toxin subunit B (CTb) tracers were injected into the pericardium and the interscapular BAT pads, respectively. Experimental animals received a 45-min occlusion of the left anterior descending coronary artery and controls received sham surgery. One week later, hearts were collected for assessment of MI infarct and SGs were collected for morphological or electrophysiological analysis. Cardiac-projecting SG neurons from MI mice had smaller cell bodies and shorter dendritic trees compared with sham animals, specifically on the left side ipsilateral to the MI. BAT-projecting neurons were not altered by MI, demonstrating the subpopulation specificity of the response. The normal size and distribution differences between BAT- and cardiac-projecting stellate ganglion neurons were not altered by MI. Patch-clamp recordings from cardiac-projecting left SG neurons revealed increased spontaneous excitatory postsynaptic currents despite the decrease in cell and dendritic tree size. Thus, increased dendritic tree size does not contribute to the enhanced sympathetic neural activity seen after MI.NEW & NOTEWORTHY Myocardial infarction (MI) causes structural and functional changes specifically in stellate ganglion neurons that project to the heart, but not in cells that project to brown adipose fat tissue.
Collapse
Affiliation(s)
- Madeleine S Barrett
- Department of Chemical Physiology and Biochemistry, Oregon Health and Science University, Portland, Oregon, United States
| | - Temerity C Bauer
- Department of Chemical Physiology and Biochemistry, Oregon Health and Science University, Portland, Oregon, United States
| | - Ming-Hua Li
- Department of Chemical Physiology and Biochemistry, Oregon Health and Science University, Portland, Oregon, United States
| | - Deborah M Hegarty
- Department of Chemical Physiology and Biochemistry, Oregon Health and Science University, Portland, Oregon, United States
| | - Clarissa M D Mota
- Department of Chemical Physiology and Biochemistry, Oregon Health and Science University, Portland, Oregon, United States
| | - Chimezie J Amaefuna
- Department of Chemical Physiology and Biochemistry, Oregon Health and Science University, Portland, Oregon, United States
| | - Susan L Ingram
- Department of Chemical Physiology and Biochemistry, Oregon Health and Science University, Portland, Oregon, United States
| | - Beth A Habecker
- Department of Chemical Physiology and Biochemistry, Oregon Health and Science University, Portland, Oregon, United States
| | - Sue A Aicher
- Department of Chemical Physiology and Biochemistry, Oregon Health and Science University, Portland, Oregon, United States
| |
Collapse
|
5
|
Usselman CW, Lindsey ML, Robinson AT, Habecker BA, Taylor CE, Merryman WD, Kimmerly D, Bender JR, Regensteiner JG, Moreau KL, Pilote L, Wenner MM, O'Brien M, Yarovinsky TO, Stachenfeld NS, Charkoudian N, Denfeld QE, Moreira-Bouchard JD, Pyle WG, DeLeon-Pennell KY. Guidelines on the use of sex and gender in cardiovascular research. Am J Physiol Heart Circ Physiol 2024; 326:H238-H255. [PMID: 37999647 DOI: 10.1152/ajpheart.00535.2023] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/31/2023] [Revised: 11/02/2023] [Accepted: 11/21/2023] [Indexed: 11/25/2023]
Abstract
In cardiovascular research, sex and gender have not typically been considered in research design and reporting until recently. This has resulted in clinical research findings from which not only all women, but also gender-diverse individuals have been excluded. The resulting dearth of data has led to a lack of sex- and gender-specific clinical guidelines and raises serious questions about evidence-based care. Basic research has also excluded considerations of sex. Including sex and/or gender as research variables not only has the potential to improve the health of society overall now, but it also provides a foundation of knowledge on which to build future advances. The goal of this guidelines article is to provide advice on best practices to include sex and gender considerations in study design, as well as data collection, analysis, and interpretation to optimally establish rigor and reproducibility needed to inform clinical decision-making and improve outcomes. In cardiovascular physiology, incorporating sex and gender is a necessary component when optimally designing and executing research plans. The guidelines serve as the first guidance on how to include sex and gender in cardiovascular research. We provide here a beginning path toward achieving this goal and improve the ability of the research community to interpret results through a sex and gender lens to enable comparison across studies and laboratories, resulting in better health for all.
Collapse
Affiliation(s)
- Charlotte W Usselman
- Cardiovascular Health and Autonomic Regulation Laboratory, Department of Kinesiology and Physical Education, McGill University, Montreal, Quebec, Canada
| | - Merry L Lindsey
- School of Graduate Studies, Meharry Medical College, Nashville, Tennessee, United States
- Research Service, Nashville Veterans Affairs Medical Center, Nashville, Tennessee, United States
| | - Austin T Robinson
- Neurovascular Physiology Laboratory, School of Kinesiology, Auburn University, Auburn, Alabama, United States
| | - Beth A Habecker
- Department of Chemical Physiology and Biochemistry and Knight Cardiovascular Institute, Oregon Health and Science University, Portland, Oregon, United States
| | - Chloe E Taylor
- School of Health Sciences, Western Sydney University, Sydney, New South Wales, Australia
| | - W David Merryman
- Department of Biomedical Engineering, Vanderbilt University, Nashville, Tennessee, United States
| | - Derek Kimmerly
- Autonomic Cardiovascular Control and Exercise Laboratory, Division of Kinesiology, School of Health and Human Performance, Faculty of Health, Dalhousie University, Halifax, Nova Scotia, Canada
| | - Jeffrey R Bender
- Section of Cardiovascular Medicine, Department of Internal Medicine, Yale Cardiovascular Research Center, New Haven, Connecticut, United States
- Department of Immunobiology, Yale University School of Medicine, New Haven, Connecticut, United States
| | - Judith G Regensteiner
- Divisions of General Internal Medicine and Cardiology, Department of Medicine, Ludeman Family Center for Women's Health Research, University of Colorado Anschutz Medical Campus, Aurora, Colorado, United States
| | - Kerrie L Moreau
- Division of Geriatrics, Department of Medicine, University of Colorado Anschutz Medical Campus, Aurora, Colorado, United States
- Eastern Colorado Health Care System, Geriatric Research Education and Clinical Center, Aurora, Colorado, United States
| | - Louise Pilote
- Centre for Outcomes Research and Evaluation, Research Institute of the McGill University Health Centre, McGill University, Montreal, Quebec, Canada
| | - Megan M Wenner
- Department of Kinesiology and Applied Physiology, University of Delaware, Newark, Delaware, United States
| | - Myles O'Brien
- School of Physiotherapy and Department of Medicine, Faculty of Health, Dalhousie University, Halifax, Nova Scotia, Canada
| | - Timur O Yarovinsky
- Section of Cardiovascular Medicine, Department of Internal Medicine, Yale Cardiovascular Research Center, New Haven, Connecticut, United States
- Department of Immunobiology, Yale University School of Medicine, New Haven, Connecticut, United States
| | - Nina S Stachenfeld
- John B. Pierce Laboratory, New Haven, Connecticut, United States
- Department of Obstetrics, Gynecology and Reproductive Sciences, Yale School of Medicine, New Haven, Connecticut, United States
| | - Nisha Charkoudian
- Thermal and Mountain Medicine Division, United States Army Research Institute of Environmental Medicine, Natick, Massachusetts, United States
| | - Quin E Denfeld
- School of Nursing and Knight Cardiovascular Institute, Oregon Health and Science University, Portland, Oregon, United States
| | - Jesse D Moreira-Bouchard
- Q.U.E.E.R. Lab, Programs in Human Physiology, Department of Health Sciences, Boston University College of Health and Rehabilitation Sciences: Sargent College, Boston, Massachusetts, United States
| | - W Glen Pyle
- IMPART Team Canada Network, Dalhousie Medicine, Saint John, New Brunswick, Canada
- Department of Biomedical Sciences, University of Guelph, Guelph, Ontario, Canada
| | - Kristine Y DeLeon-Pennell
- School of Medicine, Division of Cardiology, Department of Medicine, Medical University of South Carolina, Charleston, South Carolina, United States
- Research Service, Ralph H. Johnson Veterans Affairs Medical Center, Charleston, South Carolina, United States
| |
Collapse
|
6
|
Guevara A, Smith CER, Caldwell JL, Ngo L, Mott LR, Lee IJ, Tapa I, Wang Z, Wang L, Woodward WR, Ng GA, Habecker BA, Ripplinger CM. Chronic nicotine exposure is associated with electrophysiological and sympathetic remodeling in the intact rabbit heart. bioRxiv 2023:2023.11.23.567754. [PMID: 38045290 PMCID: PMC10690259 DOI: 10.1101/2023.11.23.567754] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/05/2023]
Abstract
Nicotine is the primary addictive component in tobacco products. Through its actions on the heart and autonomic nervous system, nicotine exposure is associated with electrophysiological changes and increased arrhythmia susceptibility. However, the underlying mechanisms are unclear. To address this, we treated rabbits with transdermal nicotine (NIC, 21 mg/day) or control (CT) patches for 28 days prior to performing dual optical mapping of transmembrane potential (RH237) and intracellular Ca 2+ (Rhod-2 AM) in isolated hearts with intact sympathetic innervation. Sympathetic nerve stimulation (SNS) was performed at the 1 st - 3 rd thoracic vertebrae, and β-adrenergic responsiveness was additionally evaluated as changes in heart rate (HR) following norepinephrine (NE) perfusion. Baseline ex vivo HR and SNS stimulation threshold were increased in NIC vs. CT ( P = 0.004 and P = 0.003 respectively). Action potential duration alternans emerged at longer pacing cycle lengths (PCL) in NIC vs. CT at baseline ( P = 0.002) and during SNS ( P = 0.0003), with similar results obtained for Ca 2+ transient alternans. SNS reduced the PCL at which alternans emerged in CT but not NIC hearts. NIC exposed hearts also tended to have slower and reduced HR responses to NE perfusion. While fibrosis was unaltered, NIC hearts had lower sympathetic nerve density ( P = 0.03) but no difference in NE content vs. CT. These results suggest both sympathetic hypo-innervation of the myocardium and diminished β-adrenergic responsiveness with NIC. This autonomic remodeling may underlie the increased risk of arrhythmias associated with nicotine exposure, which may be further exacerbated with continued long-term usage. NEW & NOTEWORTHY Here we show that chronic nicotine exposure was associated with increased heart rate, lower threshold for alternans and reduced sympathetic electrophysiological responses in the intact rabbit heart. We suggest that this was due to the sympathetic hypo-innervation of the myocardium and diminished β- adrenergic responsiveness observed following nicotine treatment. Though these differences did not result in increased arrhythmia propensity in our study, we hypothesize that prolonged nicotine exposure may exacerbate this pro-arrhythmic remodeling.
Collapse
|
7
|
Blake MR, Parrish DC, Staffenson MA, Johnson MA, Woodward WR, Habecker BA. Loss of chondroitin sulfate proteoglycan sulfation allows delayed sympathetic reinnervation after cardiac ischemia-reperfusion. Physiol Rep 2023; 11:e15702. [PMID: 37226390 DOI: 10.14814/phy2.15702] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2023] [Revised: 03/23/2023] [Accepted: 03/23/2023] [Indexed: 05/26/2023] Open
Abstract
Sympathetic nerve loss in the heart predicts the risk of ventricular arrhythmias after myocardial infarction (MI) in patients. Sympathetic denervation after cardiac ischemia-reperfusion is sustained by matrix components chondroitin sulfate proteoglycans (CSPGs) in the cardiac scar. We showed that 4,6-sulfation of CSPGs was critical for preventing nerve growth into the scar. Promoting early reinnervation with therapeutics reduces arrhythmias during the first 2 weeks after MI, but the longer-term consequences of restoring innervation are unknown. Therefore, we asked if the beneficial effects of early reinnervation were sustained. We compared cardiac function and arrhythmia susceptibility 40 days after MI in mice treated on Days 3-10 with vehicle or with intracellular sigma peptide to restore innervation. Surprisingly, both groups had normal innervation density in the cardiac scar 40 days after MI, indicating delayed reinnervation of the infarct in vehicle-treated mice. That coincided with similar cardiac function and arrhythmia susceptibility in the two groups. We investigated the mechanism allowing delayed reinnervation of the cardiac scar. We found that CSPG 4,6-sulfation, which is elevated early after ischemia-reperfusion, was reduced to control levels allowing reinnervation of the infarct. Thus, remodeling of extracellular matrix weeks after injury leads to remodeling of sympathetic neurons in the heart.
Collapse
Affiliation(s)
- Matthew R Blake
- Department of Chemical Physiology and Biochemistry, Oregon Health and Science University, Portland, Oregon, USA
| | - Diana C Parrish
- Department of Chemical Physiology and Biochemistry, Oregon Health and Science University, Portland, Oregon, USA
| | - Melanie A Staffenson
- Department of Chemical Physiology and Biochemistry, Oregon Health and Science University, Portland, Oregon, USA
| | - Morgan A Johnson
- Department of Neurology, Oregon Health and Science University, Portland, Oregon, USA
| | - William R Woodward
- Department of Chemical Physiology and Biochemistry, Oregon Health and Science University, Portland, Oregon, USA
- Department of Neurology, Oregon Health and Science University, Portland, Oregon, USA
| | - Beth A Habecker
- Department of Chemical Physiology and Biochemistry, Oregon Health and Science University, Portland, Oregon, USA
| |
Collapse
|
8
|
Clyburn C, Li MH, Ingram SL, Andresen MC, Habecker BA. Cholinergic collaterals arising from noradrenergic sympathetic neurons in mice. J Physiol 2023; 601:1247-1264. [PMID: 36797985 PMCID: PMC10065914 DOI: 10.1113/jp284059] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2022] [Accepted: 02/07/2023] [Indexed: 02/18/2023] Open
Abstract
The sympathetic nervous system vitally regulates autonomic functions, including cardiac activity. Postganglionic neurons of the sympathetic chain ganglia relay signals from the central nervous system to autonomic peripheral targets. Disrupting this flow of information often dysregulates organ function and leads to poor health outcomes. Despite the importance of these sympathetic neurons, fundamental aspects of the neurocircuitry within peripheral ganglia remain poorly understood. Conventionally, simple monosynaptic cholinergic pathways from preganglionic neurons are thought to activate postganglionic sympathetic neurons. However, early studies suggested more complex neurocircuits may be present within sympathetic ganglia. The present study recorded synaptic responses in sympathetic stellate ganglia neurons following electrical activation of the pre- and postganglionic nerve trunks and used genetic strategies to assess the presence of collateral projections between postganglionic neurons of the stellate ganglia. Orthograde activation of the preganglionic nerve trunk, T-2, uncovered high jitter synaptic latencies consistent with polysynaptic connections. Pharmacological inhibition of nicotinic acetylcholine receptors with hexamethonium blocked all synaptic events. To confirm that high jitter, polysynaptic events were due to the presence of cholinergic collaterals from postganglionic neurons within the stellate ganglion, we knocked out choline acetyltransferase in adult noradrenergic neurons. This genetic knockout eliminated orthograde high jitter synaptic events and EPSCs evoked by retrograde activation. These findings suggest that cholinergic collateral projections arise from noradrenergic neurons within sympathetic ganglia. Identifying the contributions of collateral excitation to normal physiology and pathophysiology is an important area of future study and may offer novel therapeutic targets for the treatment of autonomic imbalance. KEY POINTS: Electrical stimulation of a preganglionic nerve trunk evoked fast synaptic transmission in stellate ganglion neurons with low and high jitter latencies. Retrograde stimulation of a postganglionic nerve trunk evoked direct, all-or-none action currents and delayed nicotinic EPSCs indistinguishable from orthogradely-evoked EPSCs in stellate neurons. Nicotinic acetylcholine receptor blockade prevented all spontaneous and evoked synaptic activity. Knockout of acetylcholine production in noradrenergic neurons eliminated all retrogradely-evoked EPSCs but did not change retrograde action currents, indicating that noradrenergic neurons have cholinergic collaterals connecting neurons within the stellate ganglion.
Collapse
Affiliation(s)
- Courtney Clyburn
- Department of Chemical Physiology and Biochemistry, Oregon Health and Science University, Portland, OR, USA
| | - Ming-Hua Li
- Department of Chemical Physiology and Biochemistry, Oregon Health and Science University, Portland, OR, USA
| | - Susan L Ingram
- Department of Anesthesiology, University of Colorado Anschutz Medical Campus, Aurora, CO, USA
| | - Michael C Andresen
- Department of Chemical Physiology and Biochemistry, Oregon Health and Science University, Portland, OR, USA
| | - Beth A Habecker
- Department of Chemical Physiology and Biochemistry, Oregon Health and Science University, Portland, OR, USA
| |
Collapse
|
9
|
Denfeld QE, Purnell JQ, Lee CS, Orwoll ES, Camacho SA, Hiatt SO, Davis MR, Winters-Stone K, Woodward WR, Habecker BA. Candidate biomarkers of physical frailty in heart failure: an exploratory cross-sectional study. Eur J Cardiovasc Nurs 2023; 22:149-157. [PMID: 35727092 PMCID: PMC10243450 DOI: 10.1093/eurjcn/zvac054] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/08/2022] [Revised: 05/31/2022] [Accepted: 06/01/2022] [Indexed: 02/05/2023]
Abstract
AIMS Physical frailty is highly prevalent and predictive of worse outcomes in heart failure (HF). Candidate biomarker analysis may help in understanding the mechanisms underlying physical frailty in HF. We aimed to identify candidate biomarkers associated with physical frailty in HF using a multimarker strategy of distinct pathophysiological processes. METHODS AND RESULTS We collected data and plasma samples from 113 adults with New York Heart Association Functional Class I-IV HF. Physical frailty was measured with the Frailty Phenotype Criteria. Plasma biomarkers included: N-terminal pro-B-type natriuretic peptide, norepinephrine, dihydroxyphenylglycol, soluble tumour necrosis factor alpha receptor-1, adiponectin, insulin, glucose, insulin-like growth factor-1 (IGF-1), and myostatin. Comparative statistics and multivariate linear regression were used to test group differences and associations. The average age was 63.5 ± 15.7 years, half were women (48%), and most had a non-ischaemic aetiology of HF (73%). Physical frailty was identified in 42% and associated with female sex, higher body mass index and percent body fat, more comorbidities, and HF with preserved ejection fraction. Adjusting for Seattle HF Model projected survival score, comorbidities, body composition, and sex, physical frailty was associated with significantly lower plasma adiponectin [β ± standard error (SE) -0.28 ± 0.14, P = 0.047], IGF-1 (β ± SE -0.21 ± 0.10, P = 0.032), and myostatin (β ± SE -0.22 ± 0.09, P = 0.011). In sex-stratified analyses, IGF-1 and myostatin were significantly associated with physical frailty in men but not women. CONCLUSION We identified biomarkers involved in adipose tissue and skeletal muscle development, maintenance, and function that were associated with physical frailty in HF.
Collapse
Affiliation(s)
- Quin E. Denfeld
- Oregon Health & Science University, School of Nursing, Portland, OR, USA
- Oregon Health & Science University, Knight Cardiovascular Institute, Portland, OR, USA
| | - Jonathan Q. Purnell
- Oregon Health & Science University, Knight Cardiovascular Institute, Portland, OR, USA
| | - Christopher S. Lee
- Boston College, William F. Connell School of Nursing, Chestnut Hill, MA, USA
- Australian Catholic University, Melbourne, Australia
| | - Eric S. Orwoll
- Oregon Health & Science University, School of Medicine, Portland, OR, USA
| | - S. Albert Camacho
- Oregon Health & Science University, Knight Cardiovascular Institute, Portland, OR, USA
| | - Shirin O. Hiatt
- Oregon Health & Science University, School of Nursing, Portland, OR, USA
| | - Mary Roberts Davis
- Oregon Health & Science University, School of Nursing, Portland, OR, USA
| | - Kerri Winters-Stone
- Oregon Health & Science University, School of Nursing, Portland, OR, USA
- Oregon Health & Science University, Knight Cancer Institute, Portland, OR, USA
| | - William R. Woodward
- Oregon Health & Science University, Department of Chemical Physiology & Biochemistry, Portland, OR, USA
| | - Beth A. Habecker
- Oregon Health & Science University, Knight Cardiovascular Institute, Portland, OR, USA
- Oregon Health & Science University, Department of Chemical Physiology & Biochemistry, Portland, OR, USA
| |
Collapse
|
10
|
Sepe JJ, Gardner RT, Blake MR, Brooks DM, Staffenson MA, Betts CB, Sivagnanam S, Larson W, Kumar S, Bayles RG, Jin H, Cohen MS, Coussens LM, Habecker BA. Therapeutics That Promote Sympathetic Reinnervation Modulate the Inflammatory Response After Myocardial Infarction. JACC Basic Transl Sci 2022; 7:915-930. [PMID: 36317132 PMCID: PMC9617125 DOI: 10.1016/j.jacbts.2022.04.009] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/11/2022] [Revised: 04/13/2022] [Accepted: 04/15/2022] [Indexed: 02/05/2023]
Abstract
Myocardial infarction (MI) triggers an inflammatory response that transitions from pro-inflammatory to reparative over time. Restoring sympathetic nerves in the heart after MI prevents arrhythmias. This study investigated if reinnervation altered the immune response after MI. This study used quantitative multiplex immunohistochemistry to identify the immune cells present in the heart 2 weeks after ischemia-reperfusion. Two therapeutics stimulated reinnervation, preventing arrhythmias and shifting the immune response from inflammatory to reparative, with fewer pro-inflammatory macrophages and more regulatory T cells and reparative macrophages. Treatments did not alter macrophage phenotype in vitro, which suggested reinnervation contributed to the altered immune response.
Collapse
Key Words
- ACh, acetylcholine
- IP, intraperitoneal
- ISP, intracellular sigma peptide
- MI, myocardial infarction
- NE, norepinephrine
- PBS, phosphate-buffered saline
- TH, tyrosine hydroxylase
- Tregs, regulatory T cells
- VEH, vehicle
- inflammation
- mIHC, multiplex immunohistochemistry
- macrophages
- multiplex IHC
- myocardial infarction
- sympathetic nervous system
- β1-AR, adrenergic receptor
Collapse
Affiliation(s)
- Joseph J. Sepe
- Department of Chemical Physiology and Biochemistry, Oregon Health and Science University, Portland, Oregon, USA
- Department of Medicine, Knight Cardiovascular Institute, Oregon Health and Science University, Portland, Oregon, USA
| | - Ryan T. Gardner
- Department of Chemical Physiology and Biochemistry, Oregon Health and Science University, Portland, Oregon, USA
- Department of Medicine, Knight Cardiovascular Institute, Oregon Health and Science University, Portland, Oregon, USA
| | - Matthew R. Blake
- Department of Chemical Physiology and Biochemistry, Oregon Health and Science University, Portland, Oregon, USA
| | - Deja M. Brooks
- Department of Chemical Physiology and Biochemistry, Oregon Health and Science University, Portland, Oregon, USA
| | - Melanie A. Staffenson
- Department of Chemical Physiology and Biochemistry, Oregon Health and Science University, Portland, Oregon, USA
| | - Courtney B. Betts
- Department of Cell, Developmental and Cancer Biology, Oregon Health and Science University, Portland, Oregon, USA
- Knight Cancer Institute, Oregon Health and Science University, Portland, Oregon, USA
| | - Sam Sivagnanam
- Department of Cell, Developmental and Cancer Biology, Oregon Health and Science University, Portland, Oregon, USA
- Knight Cancer Institute, Oregon Health and Science University, Portland, Oregon, USA
| | - William Larson
- Department of Cell, Developmental and Cancer Biology, Oregon Health and Science University, Portland, Oregon, USA
- Knight Cancer Institute, Oregon Health and Science University, Portland, Oregon, USA
| | - Sushil Kumar
- Department of Cell, Developmental and Cancer Biology, Oregon Health and Science University, Portland, Oregon, USA
- Knight Cancer Institute, Oregon Health and Science University, Portland, Oregon, USA
| | - Richard G. Bayles
- Department of Chemical Physiology and Biochemistry, Oregon Health and Science University, Portland, Oregon, USA
| | - Haihong Jin
- Department of Chemical Physiology and Biochemistry, Oregon Health and Science University, Portland, Oregon, USA
| | - Michael S. Cohen
- Department of Chemical Physiology and Biochemistry, Oregon Health and Science University, Portland, Oregon, USA
| | - Lisa M. Coussens
- Department of Cell, Developmental and Cancer Biology, Oregon Health and Science University, Portland, Oregon, USA
- Knight Cancer Institute, Oregon Health and Science University, Portland, Oregon, USA
| | - Beth A. Habecker
- Department of Chemical Physiology and Biochemistry, Oregon Health and Science University, Portland, Oregon, USA
- Department of Medicine, Knight Cardiovascular Institute, Oregon Health and Science University, Portland, Oregon, USA
| |
Collapse
|
11
|
Barrett MS, Hegarty DM, Habecker BA, Aicher SA. Distinct morphology of cardiac- and brown adipose tissue-projecting neurons in the stellate ganglia of mice. Physiol Rep 2022; 10:e15334. [PMID: 35621038 PMCID: PMC9136702 DOI: 10.14814/phy2.15334] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2022] [Revised: 05/02/2022] [Accepted: 05/07/2022] [Indexed: 11/24/2022] Open
Abstract
Sympathetic neurons that innervate the heart are located primarily in the stellate ganglia (SG), which also contains neurons that project to brown adipose tissue (BAT). These studies were designed to examine the morphology of these two populations (cardiac- and BAT-projecting) and their target connectivity. We examined SG neurons in C57BL/6J mice following injections of the retrograde tracer cholera toxin B (CTb) conjugated to Alexa Fluor 488 and Alexa Fluor 555, into cardiac tissue and intrascapular BAT. BAT-projecting SG neurons were widely dispersed in SG, while cardiac-projecting SG neurons were localized primarily near the inferior cardiac nerve base. SG neurons were not dual-labeled, suggesting that sympathetic innervation is specific to the heart and BAT, supporting the idea of "labeled lines" of efferents. Morphologically, cardiac-projecting SG somata had more volume and were less abundant than BAT-projecting neurons using our tracer-labeling paradigm. We found a positive correlation between the number of primary dendrites per neuron and soma volume in cardiac-projecting SG neurons, though not in BAT-projecting neurons. In both SG subpopulations, the number of cholinergic inputs marked with vesicular acetylcholine transporter (VAChT) puncta contacting the soma was positively correlated to soma volume, suggesting scaling of inputs across a range of neuronal sizes. In separate studies using dual tracing from left and right BAT, we found that BAT-projecting SG neurons were located predominately ipsilateral to the injection, but a small subset of SG neurons project bilaterally to BAT. This tracing approach will allow the assessment of cell-specific mechanisms of plasticity within subpopulations of SG neurons.
Collapse
Affiliation(s)
- Madeleine S Barrett
- Department of Chemical Physiology & Biochemistry, Oregon Health & Science University, Portland, Oregon, USA
| | - Deborah M Hegarty
- Department of Chemical Physiology & Biochemistry, Oregon Health & Science University, Portland, Oregon, USA
| | - Beth A Habecker
- Department of Chemical Physiology & Biochemistry, Oregon Health & Science University, Portland, Oregon, USA
| | - Sue A Aicher
- Department of Chemical Physiology & Biochemistry, Oregon Health & Science University, Portland, Oregon, USA
| |
Collapse
|
12
|
Blake MR, Parrish DC, Staffenson MA, Sueda S, Woodward WR, Habecker BA. Chondroitin Sulfate Proteoglycan 4,6 sulfation regulates sympathetic nerve regeneration after myocardial infarction. eLife 2022; 11:78387. [PMID: 35604022 PMCID: PMC9197393 DOI: 10.7554/elife.78387] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2022] [Accepted: 05/22/2022] [Indexed: 11/13/2022] Open
Abstract
Sympathetic denervation of the heart following ischemia/reperfusion induced myocardial infarction (MI) is sustained by chondroitin sulfate proteoglycans (CSPGs) in the cardiac scar. Denervation predicts risk of sudden cardiac death in humans. Blocking CSPG signaling restores sympathetic axon outgrowth into the cardiac scar, decreasing arrhythmia susceptibility. Axon growth inhibition by CSPGs is thought to depend on the sulfation status of the glycosaminoglycans (CS-GAGs) attached to the core protein. Tandem sulfation of CS-GAGs at the 4th (4S) and 6th (6S) positions of n-acetyl-galactosamine inhibits outgrowth in several types of neurons within the central nervous system, but it is not known if sulfation is similarly critical during peripheral nerve regeneration. We asked if CSPG sulfation prevented sympathetic axon outgrowth. Neurite outgrowth of dissociated rat sympathetic neurons across purified CSPGs is restored in vitro by reducing 4S with the 4-sulfatase enzyme Arylsulfatase-B (ARSB). Additionally, we co-cultured mouse cardiac scar tissue with mouse sympathetic ganglia ex vivo and found that reducing 4S with ARSB restored axon outgrowth to control levels. We examined levels of the enzymes responsible for adding and removing sulfation to CS-GAGs by western blot to determine if they were altered in the left ventricle after MI. We found that CHST15 (4S dependent 6-sulfotransferase) was upregulated, and ARSB was downregulated after MI. Increased CHST15 combined with decreased ARSB suggests a mechanism for production and maintenance of sulfated CSPGs in the cardiac scar. We altered tandem sulfated 4S,6S CS-GAGs in vivo by transient siRNA knockdown of Chst15 and found that reducing 4S,6S restored Tyrosine Hydroxylase (TH) positive sympathetic nerve fibers in the cardiac scar and reduced arrhythmias using a mouse model of MI. Overall, our results suggest that modulating CSPG-sulfation after MI may be a therapeutic target to promote sympathetic nerve regeneration in the cardiac scar and reduce post-MI cardiac arrhythmias.
Collapse
Affiliation(s)
- Matthew R Blake
- Department of Chemical Physiology and Biochemistry, Oregon Health and Science University, Portland, United States
| | - Diana C Parrish
- Department of Chemical Physiology and Biochemistry, Oregon Health and Science University, Portland, United States
| | - Melanie A Staffenson
- Department of Chemical Physiology and Biochemistry, Oregon Health and Science University, Portland, United States
| | | | - William R Woodward
- Department of Chemical Physiology and Biochemistry, Oregon Health and Science University, Portland, United States
| | - Beth A Habecker
- Department of Chemical Physiology and Biochemistry, Oregon Health and Science University, Portland, United States
| |
Collapse
|
13
|
Clyburn C, Andresen MC, Ingram SL, Habecker BA. Evidence for Cholinergic Collateral Projections between Sympathetic Neurons in the Murine Stellate Ganglia. FASEB J 2022. [DOI: 10.1096/fasebj.2022.36.s1.r3743] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Courtney Clyburn
- Chemical Physiology and BiochemistryOregon Health and Science UniversityPortlandOR
| | - Michael C. Andresen
- Chemical Physiology and BiochemistryOregon Health and Science UniversityPortlandOR
| | - Susan L. Ingram
- Neurological SurgeryOregon Health and Science UniversityPortlandOR
| | - Beth A. Habecker
- Chemical Physiology and BiochemistryOregon Health and Science UniversityPortlandOR
| |
Collapse
|
14
|
Barrett MS, Hegarty DM, Habecker BA, Aicher SA. Diverse Morphology of Sympathetic Neuron Subpopulations in the Stellate Ganglia. FASEB J 2022. [DOI: 10.1096/fasebj.2022.36.s1.l7605] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Madeleine S. Barrett
- Chemical Physiology and BiochemistryOregon Health and Science UniversityPortlandOR
| | - Deborah M. Hegarty
- Chemical Physiology and BiochemistryOregon Health and Science UniversityPortlandOR
| | - Beth A. Habecker
- Chemical Physiology and BiochemistryOregon Health and Science UniversityPortlandOR
| | - Sue A. Aicher
- Chemical Physiology and BiochemistryOregon Health and Science UniversityPortlandOR
| |
Collapse
|
15
|
Wang L, Guevara AM, Caldwell JL, Lee IJ(E, Habecker BA, Ripplinger CM. BS-512-01 PHARMACOLOGICAL SYMPATHETIC REINNERVATION AFTER MYOCARDIAL INFARCTION PREVENTS ARRHYTHMIAS IN THE MOUSE HEART. Heart Rhythm 2022. [DOI: 10.1016/j.hrthm.2022.03.095] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
|
16
|
Blake MR, Gardner RT, Jin H, Staffenson MA, Rueb NJ, Barrios AM, Dudley GB, Cohen MS, Habecker BA. Small Molecules Targeting PTPσ-Trk Interactions Promote Sympathetic Nerve Regeneration. ACS Chem Neurosci 2022; 13:688-699. [PMID: 35156811 DOI: 10.1021/acschemneuro.1c00854] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
Chondroitin sulfate proteoglycans (CSPGs) prevent sympathetic nerve regeneration in the heart after myocardial infarction and prevent central nerve regrowth after traumatic brain injury and spinal cord injury. Currently, there are no small-molecule therapeutics to promote nerve regeneration through CSPG-containing scars. CSPGs bind to monomers of receptor protein tyrosine phosphatase sigma (PTPσ) on the surface of neurons, enhancing the ability of PTPσ to bind and dephosphorylate tropomyosin receptor kinases (Trks), inhibiting their activity and preventing axon outgrowth. Targeting PTPσ-Trk interactions is thus a potential therapeutic target. Here, we describe the development and synthesis of small molecules (HJ-01 and HJ-02) that disrupt PTPσ interactions with Trks, enhance Trk signaling, and promote sympathetic nerve regeneration over CSPGs.
Collapse
Affiliation(s)
- Matthew R. Blake
- Department of Chemical Physiology and Biochemistry, Oregon Health and Science University, Portland, Oregon 97239, United States
- Graduate Program in Biomedical Sciences, Oregon Health and Science University, Portland, Oregon 97239, United States
| | - Ryan T. Gardner
- Department of Chemical Physiology and Biochemistry, Oregon Health and Science University, Portland, Oregon 97239, United States
| | - Haihong Jin
- Department of Chemical Physiology and Biochemistry, Oregon Health and Science University, Portland, Oregon 97239, United States
| | - Melanie A. Staffenson
- Department of Chemical Physiology and Biochemistry, Oregon Health and Science University, Portland, Oregon 97239, United States
| | - Nicole J. Rueb
- Department of Medicinal Chemistry, University of Utah College of Pharmacy, Salt Lake City, Utah 84112, United States
| | - Amy M. Barrios
- Department of Medicinal Chemistry, University of Utah College of Pharmacy, Salt Lake City, Utah 84112, United States
| | - Gregory B. Dudley
- C. Eugene Bennett Department of Chemistry, West Virginia University, Morgantown, West Virginia 26506, United States
| | - Michael S. Cohen
- Department of Chemical Physiology and Biochemistry, Oregon Health and Science University, Portland, Oregon 97239, United States
| | - Beth A. Habecker
- Department of Chemical Physiology and Biochemistry, Oregon Health and Science University, Portland, Oregon 97239, United States
| |
Collapse
|
17
|
Mehra R, Tjurmina OA, Ajijola OA, Arora R, Bolser DC, Chapleau MW, Chen PS, Clancy CE, Delisle BP, Gold MR, Goldberger JJ, Goldstein DS, Habecker BA, Handoko ML, Harvey R, Hummel JP, Hund T, Meyer C, Redline S, Ripplinger CM, Simon MA, Somers VK, Stavrakis S, Taylor-Clark T, Undem BJ, Verrier RL, Zucker IH, Sopko G, Shivkumar K. Research Opportunities in Autonomic Neural Mechanisms of Cardiopulmonary Regulation: A Report From the National Heart, Lung, and Blood Institute and the National Institutes of Health Office of the Director Workshop. JACC Basic Transl Sci 2022; 7:265-293. [PMID: 35411324 PMCID: PMC8993767 DOI: 10.1016/j.jacbts.2021.11.003] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/16/2021] [Revised: 11/09/2021] [Accepted: 11/10/2021] [Indexed: 12/22/2022]
Abstract
This virtual workshop was convened by the National Heart, Lung, and Blood Institute, in partnership with the Office of Strategic Coordination of the Office of the National Institutes of Health Director, and held September 2 to 3, 2020. The intent was to assemble a multidisciplinary group of experts in basic, translational, and clinical research in neuroscience and cardiopulmonary disorders to identify knowledge gaps, guide future research efforts, and foster multidisciplinary collaborations pertaining to autonomic neural mechanisms of cardiopulmonary regulation. The group critically evaluated the current state of knowledge of the roles that the autonomic nervous system plays in regulation of cardiopulmonary function in health and in pathophysiology of arrhythmias, heart failure, sleep and circadian dysfunction, and breathing disorders. Opportunities to leverage the Common Fund's SPARC (Stimulating Peripheral Activity to Relieve Conditions) program were characterized as related to nonpharmacologic neuromodulation and device-based therapies. Common themes discussed include knowledge gaps, research priorities, and approaches to develop novel predictive markers of autonomic dysfunction. Approaches to precisely target neural pathophysiological mechanisms to herald new therapies for arrhythmias, heart failure, sleep and circadian rhythm physiology, and breathing disorders were also detailed.
Collapse
Key Words
- ACE, angiotensin-converting enzyme
- AD, autonomic dysregulation
- AF, atrial fibrillation
- ANS, autonomic nervous system
- Ach, acetylcholine
- CNS, central nervous system
- COPD, chronic obstructive pulmonary disease
- CSA, central sleep apnea
- CVD, cardiovascular disease
- ECG, electrocardiogram
- EV, extracellular vesicle
- GP, ganglionated plexi
- HF, heart failure
- HFpEF, heart failure with preserved ejection fraction
- HFrEF, heart failure with reduced ejection fraction
- HRV, heart rate variability
- LQT, long QT
- MI, myocardial infarction
- NE, norepinephrine
- NHLBI, National Heart, Lung, and Blood Institute
- NPY, neuropeptide Y
- NREM, non-rapid eye movement
- OSA, obstructive sleep apnea
- PAH, pulmonary arterial hypertension
- PV, pulmonary vein
- REM, rapid eye movement
- RV, right ventricular
- SCD, sudden cardiac death
- SDB, sleep disordered breathing
- SNA, sympathetic nerve activity
- SNSA, sympathetic nervous system activity
- TLD, targeted lung denervation
- asthma
- atrial fibrillation
- autonomic nervous system
- cardiopulmonary
- chronic obstructive pulmonary disease
- circadian
- heart failure
- pulmonary arterial hypertension
- sleep apnea
- ventricular arrhythmia
Collapse
Affiliation(s)
- Reena Mehra
- Cleveland Clinic, Cleveland, Ohio, USA
- Case Western Reserve University, Cleveland, Ohio, USA
| | - Olga A. Tjurmina
- National Heart, Lung, and Blood Institute, Bethesda, Maryland, USA
| | | | - Rishi Arora
- Feinberg School of Medicine at Northwestern University, Chicago, Illinois, USA
| | | | - Mark W. Chapleau
- University of Iowa Carver College of Medicine, Iowa City, Iowa, USA
| | | | | | | | - Michael R. Gold
- Medical University of South Carolina, Charleston, South Carolina, USA
| | | | - David S. Goldstein
- National Institute of Neurological Disorders and Stroke, Bethesda, Maryland, USA
| | - Beth A. Habecker
- Oregon Health and Science University School of Medicine, Portland, Oregon, USA
| | - M. Louis Handoko
- Amsterdam University Medical Centers, Amsterdam, the Netherlands
| | | | - James P. Hummel
- Yale University School of Medicine, New Haven, Connecticut, USA
| | | | | | | | | | - Marc A. Simon
- University of Pittsburgh Medical Center, Pittsburgh, Pennsylvania, USA
- University of California-San Francisco, San Francisco, California, USA
| | | | - Stavros Stavrakis
- University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma, USA
| | | | | | - Richard L. Verrier
- Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, Massachusetts, USA
| | | | - George Sopko
- National Heart, Lung, and Blood Institute, Bethesda, Maryland, USA
| | | |
Collapse
|
18
|
Clyburn C, Andresen MC, Ingram SL, Habecker BA. Untangling Peripheral Sympathetic Neurocircuits. Front Cardiovasc Med 2022; 9:842656. [PMID: 35224065 PMCID: PMC8866570 DOI: 10.3389/fcvm.2022.842656] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2021] [Accepted: 01/19/2022] [Indexed: 11/13/2022] Open
Abstract
The sympathetic nervous system plays a critical role in regulating many autonomic functions, including cardiac rhythm. The postganglionic neurons in the sympathetic chain ganglia are essential components that relay sympathetic signals to target tissues and disruption of their activity leads to poor health outcomes. Despite this importance, the neurocircuitry within sympathetic ganglia is poorly understood. Canonically, postganglionic sympathetic neurons are thought to simply be activated by monosynaptic inputs from preganglionic cholinergic neurons of the intermediolateral cell columns of the spinal cord. Early electrophysiological studies of sympathetic ganglia where the peripheral nerve trunks were electrically stimulated identified excitatory cholinergic synaptic events in addition to retrograde action potentials, leading some to speculate that excitatory collateral projections are present. However, this seemed unlikely since sympathetic postganglionic neurons were known to synthesize and release norepinephrine and expression of dual neurochemical phenotypes had not been well recognized. In vitro studies clearly established the capacity of cultured sympathetic neurons to express and release acetylcholine and norepinephrine throughout development and even in pathophysiological conditions. Given this insight, we believe that the canonical view of ganglionic transmission needs to be reevaluated and may provide a mechanistic understanding of autonomic imbalance in disease. Further studies likely will require genetic models manipulating neurochemical phenotypes within sympathetic ganglia to resolve the function of cholinergic collateral projections between postganglionic neurons. In this perspective article, we will discuss the evidence for collateral projections in sympathetic ganglia, determine if current laboratory techniques could address these questions, and discuss potential obstacles and caveats.
Collapse
Affiliation(s)
- Courtney Clyburn
- Department of Chemical Physiology and Biochemistry, Oregon Health and Science University, Portland, OR, United States
| | - Michael C. Andresen
- Department of Chemical Physiology and Biochemistry, Oregon Health and Science University, Portland, OR, United States
| | - Susan L. Ingram
- Department of Neurological Surgery, Oregon Health and Science University, Portland, OR, United States
| | - Beth A. Habecker
- Department of Chemical Physiology and Biochemistry, Oregon Health and Science University, Portland, OR, United States
- *Correspondence: Beth A. Habecker
| |
Collapse
|
19
|
Denfeld QE, Camacho SA, Dieckmann N, Hiatt SO, Davis MR, Cramer DV, Rupert A, Habecker BA, Lee CS. Background and Design of the Biological and Physiological Mechanisms of Symptom Clusters in Heart Failure (BIOMES-HF) Study. J Card Fail 2022; 28:973-981. [PMID: 35045322 DOI: 10.1016/j.cardfail.2022.01.003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2021] [Revised: 01/05/2022] [Accepted: 01/06/2022] [Indexed: 10/19/2022]
Abstract
BACKGROUND Symptoms, which often cluster together, are a significant problem in heart failure (HF). There is considerable heterogeneity in symptom burden, particularly in the vulnerable transition period after a hospitalization for HF, and the biological underpinnings of symptom during transitions are unclear. The purpose of this paper is to describe the background and design of a study that addresses these knowledge gaps, entitled "Biological and Physiological Mechanisms of Symptom Clusters in Heart Failure" (BIOMES-HF). STUDY DESIGN AND METHODS BIOMES-HF is a prospective gender- and age-balanced longitudinal study of 240 adults during the 6-month transition period after a HF hospitalization. The aims are to: 1) identify clusters of change in physical symptoms, 2) quantify longitudinal associations between biomarkers and physical symptoms, and 3) quantify longitudinal associations between physical frailty and physical symptoms among adults with heart failure. We will measure multiple symptoms, biomarkers, and physical frailty at discharge and then at 1 week and 1, 3, and 6 months post-hospitalization. We will use growth mixture modeling and longitudinal mediation modeling to examine changes in symptoms, biomarkers, and physical frailty post-HF hospitalization and associations therein. CONCLUSIONS This innovative study will advance HF symptom science by utilizing a multi-biomarker panel and the physical frailty phenotype to capture the multifaceted nature of HF. Using advanced quantitative modeling, we will characterize heterogeneity and identify potential mechanisms of symptoms in HF. As a result, this research will pinpoint amenable targets for intervention to provide better, individualized treatment to improve symptom burden in HF. BRIEF LAY SUMMARY Adults with heart failure may have significant symptom burden. This study is designed to shed light on our understanding of the role of biological and physiological mechanisms in explaining heart failure symptoms, particularly groups of co-occurring symptoms, over time. We will explore how symptoms, biomarkers, and physical frailty changes after a heart failure hospitalization. The knowledge generated from this study will be used to guide the management and self-care for adults with heart failure.
Collapse
Affiliation(s)
- Quin E Denfeld
- Oregon Health & Science University School of Nursing, Portland, OR, USA; Oregon Health & Science University Knight Cardiovascular Institute Portland, OR, USA.
| | - S Albert Camacho
- Oregon Health & Science University Knight Cardiovascular Institute Portland, OR, USA
| | - Nathan Dieckmann
- Oregon Health & Science University School of Nursing, Portland, OR, USA; Oregon Health & Science University School of Medicine Division of Psychology, Portland, OR
| | - Shirin O Hiatt
- Oregon Health & Science University School of Nursing, Portland, OR, USA
| | | | - Daniela V Cramer
- Oregon Health & Science University School of Nursing, Portland, OR, USA
| | - Allissah Rupert
- Oregon Health & Science University School of Nursing, Portland, OR, USA
| | - Beth A Habecker
- Oregon Health & Science University Knight Cardiovascular Institute Portland, OR, USA; Oregon Health & Science University Department of Chemical Physiology & Biochemistry, Portland, OR, USA
| | - Christopher S Lee
- Boston College William F. Connell School of Nursing, Chestnut Hill, MA, USA; Australian Catholic University, Melbourne, Australia
| |
Collapse
|
20
|
Denfeld QE, Lee CS, Habecker BA. A Primer on Incorporating Sex as a Biological Variable into the Conduct and Reporting of Basic and Clinical Research Studies. Am J Physiol Heart Circ Physiol 2022; 322:H350-H354. [PMID: 35030071 DOI: 10.1152/ajpheart.00605.2021] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The recent move to require sex as a biological variable (SABV), which includes gender, into the reporting of research published by the American Journal of Physiology - Heart and Circulatory Physiology follows a growing, and much-needed, trend by journals. Understandably, there is concern over how to do this without adding considerable work, especially if one's primary research focus is not on elucidating sex/gender differences. The purpose of this article is to provide additional guidance and examples on how to incorporate SABV into the conduct and reporting of basic and clinical research. Using examples from our research, which includes both studies focused and not focused on sex/gender differences, we offer suggestions for how to incorporate SABV into basic and clinical research studies.
Collapse
Affiliation(s)
- Quin E Denfeld
- Oregon Health & Science University School of Nursing, Portland, OR, United States.,Oregon Health & Science University Knight Cardiovascular Institute, Portland, OR, United States
| | - Christopher S Lee
- William F. Connell School of Nursing, Boston College, Chestnut Hill, MA, United States.,Australian Catholic University, Melbourne, Victoria, Australia
| | - Beth A Habecker
- Oregon Health & Science University Knight Cardiovascular Institute, Portland, OR, United States.,Oregon Health & Science University Department of Chemical Physiology and Biochemistry, Portland, OR, United States
| |
Collapse
|
21
|
Clyburn C, Sepe JJ, Habecker BA. What gets on the nerves of cardiac patients? Pathophysiological changes in cardiac innervation. J Physiol 2021; 600:451-461. [PMID: 34921407 PMCID: PMC8810748 DOI: 10.1113/jp281118] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2021] [Accepted: 12/10/2021] [Indexed: 11/08/2022] Open
Abstract
The autonomic nervous system regulates cardiac function by balancing the actions of sympathetic and parasympathetic inputs to the heart. Intrinsic cardiac neurocircuits integrate these autonomic signals to fine-tune cardiac control, and sensory feedback loops regulate autonomic transmission in the face of external stimuli. These interconnected neural systems allow the heart to adapt to constantly changing circumstances that range from simple fluctuations in body position to running a marathon. The cardiac reflexes that serve to maintain homeostasis in health are disrupted in many disease states. This is often characterized by increased sympathetic and decreased parasympathetic transmission. Studies of cardiovascular disease reveal remodelling of cardiac neurocircuits at several functional and anatomical levels. Central circuits change so that sympathetic pathways become hyperactive, while parasympathetic circuits exhibit decreased activity. Peripheral sensory nerves also become hyperactive in disease, which increases patients' risk for poor cardiac outcomes. Injury and disease also alter the types of neurotransmitters and neuropeptides released by autonomic nerves in the heart, and can lead to regional hyperinnervation (increased nerve density) or denervation (decreased nerve density) of cardiac tissue. The mechanisms responsible for neural remodelling are not fully understood, but neurotrophins and inflammatory cytokines are likely involved. Areas of active investigation include the role of immune cells and inflammation in neural remodelling, as well as the role of glia in modulating peripheral neuronal activity. Our growing understanding of autonomic dysfunction in disease has facilitated development of new therapeutic strategies to improve health outcomes.
Collapse
Affiliation(s)
- Courtney Clyburn
- Department of Chemical Physiology and Biochemistry, Oregon Health and Science University, Portland, Oregon, USA
| | - Joseph J Sepe
- Department of Chemical Physiology and Biochemistry, Oregon Health and Science University, Portland, Oregon, USA
| | - Beth A Habecker
- Department of Chemical Physiology and Biochemistry, Oregon Health and Science University, Portland, Oregon, USA
| |
Collapse
|
22
|
Olaopa MA, Ai T, Chao B, Xiao X, Vatta M, Habecker BA. Phosphorylation of Lamin A/C at serine 22 modulates Na v 1.5 function. Physiol Rep 2021; 9:e15121. [PMID: 34806324 PMCID: PMC8606869 DOI: 10.14814/phy2.15121] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2021] [Revised: 10/29/2021] [Accepted: 10/31/2021] [Indexed: 12/17/2022] Open
Abstract
Variants in the LMNA gene, which encodes for Lamin A/C, are associated with cardiac conduction disease (CCD). We previously reported that Lamin A/C variants p.R545H and p.A287Lfs*193, which were identified in CCD patients, decreased peak INa in HEK-293 cells expressing Nav 1.5. Decreased peak INa in the cardiac conduction system could account for patients' atrioventricular block. We found that serine 22 (Ser 22) phosphorylation of Lamin A/C was decreased in the p.R545H variant and hypothesized that lamin phosphorylation modulated Nav 1.5 activity. To test this hypothesis, we assessed Nav 1.5 function in HEK-293 cells co-transfected with LMNA variants or treated with the small molecule LBL1 (lamin-binding ligand 1). LBL1 decreased Ser 22 phosphorylation by 65% but did not affect Nav 1.5 function. To test the complete loss of phosphorylation, we generated a version of LMNA with serine 22 converted to alanine 22 (S22A-LMNA); and a version of mutant R545H-LMNA that mimics phosphorylation via serine 22 to aspartic acid 22 substitution (S22D-R545H-LMNA). We found that S22A-LMNA inhibited Lamin-mediated activation of peak INa by 63% and shifted voltage-dependency of steady-state inactivation of Nav 1.5. Conversely, S22D-R545H-LMNA abolished the effects of mutant R545H-LMNA on voltage-dependency but not peak INa . We conclude that Lamin A/C Ser 22 phosphorylation can modulate Nav 1.5 function and contributes to the mechanism by which R545H-LMNA alters Nav 1.5 function. The differential impact of complete versus partial loss of Ser 22 phosphorylation suggests a threshold of phosphorylation that is required for full Nav 1.5 modulation. This is the first study to link Lamin A/C phosphorylation to Nav 1.5 function.
Collapse
Affiliation(s)
- Michael A. Olaopa
- Department of Chemical Physiology and BiochemistryOregon Health & Science UniversityPortlandOregonUSA
- Krannert Institute of CardiologyDepartment of MedicineIndiana University School of MedicineIndianapolisIndianaUSA
| | - Tomohiko Ai
- Krannert Institute of CardiologyDepartment of MedicineIndiana University School of MedicineIndianapolisIndianaUSA
- Department of Clinical Laboratory MedicineJuntendo UniversityTokyoJapan
| | - Bo Chao
- Department of Chemical Physiology and BiochemistryOregon Health & Science UniversityPortlandOregonUSA
| | - Xiangshu Xiao
- Department of Chemical Physiology and BiochemistryOregon Health & Science UniversityPortlandOregonUSA
| | - Matteo Vatta
- Krannert Institute of CardiologyDepartment of MedicineIndiana University School of MedicineIndianapolisIndianaUSA
| | - Beth A. Habecker
- Department of Chemical Physiology and BiochemistryOregon Health & Science UniversityPortlandOregonUSA
| |
Collapse
|
23
|
Denfeld QE, Habecker BA, Camacho SA, Roberts Davis M, Gupta N, Hiatt SO, Medysky ME, Purnell JQ, Winters-Stone K, Lee CS. Characterizing Sex Differences in Physical Frailty Phenotypes in Heart Failure. Circ Heart Fail 2021; 14:e008076. [PMID: 34428925 DOI: 10.1161/circheartfailure.120.008076] [Citation(s) in RCA: 29] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
BACKGROUND Although women with heart failure (HF) are potentially more likely to be physically frail compared with men with HF, the underlying contributors to this sex difference are poorly understood. The purpose of this study was to characterize sex differences in physical frailty phenotypes in HF. METHODS We prospectively enrolled adults with class I-IV HF. Physical frailty was measured with the frailty phenotype criteria. Symptoms of dyspnea, sleep-related impairment, pain interference, depression, and anxiety were assessed. Body composition was measured using dual-energy x-ray absorptiometry. Simple comparative statistics and stepwise regression modeling were used. RESULTS The average age of the sample (n=115) was 63.6±15.7 years, 49% were women, and 73% had nonischemic cause. Forty-three percent of the sample was physically frail. Women had a 4.6 times greater odds of being physically frail compared with men, adjusting for covariates (odds ratio=4.63 [95% CI, 1.81-11.84], P=0.001). Both physically frail men and women were characterized by more type 2 diabetes, higher comorbidity burden, and worse dyspnea symptoms. Physically frail women had significantly worse symptoms compared with non-physically frail women but no difference in body composition characteristics. Physically frail men had significantly lower appendicular muscle mass, higher percent fat, lower hemoglobin, and more depressive symptoms compared with non-physically frail men. CONCLUSIONS Women are significantly more likely to be physically frail compared with men in HF. Physical frailty in both women and men is characterized by comorbidities and worse symptoms; physical frailty in men is characterized by worse physiological characteristics.
Collapse
Affiliation(s)
- Quin E Denfeld
- School of Nursing (Q.E.D., M.R.D., S.O.H., M.E.M., K.W.-S.), Oregon Health and Science University, Portland.,Knight Cardiovascular Institute (Q.E.D., B.A.H., S.A.C., N.G., J.Q.P.), Oregon Health and Science University, Portland
| | - Beth A Habecker
- Knight Cardiovascular Institute (Q.E.D., B.A.H., S.A.C., N.G., J.Q.P.), Oregon Health and Science University, Portland.,Department of Chemical Physiology and Biochemistry (B.A.H.), Oregon Health and Science University, Portland
| | - S Albert Camacho
- Knight Cardiovascular Institute (Q.E.D., B.A.H., S.A.C., N.G., J.Q.P.), Oregon Health and Science University, Portland
| | - Mary Roberts Davis
- School of Nursing (Q.E.D., M.R.D., S.O.H., M.E.M., K.W.-S.), Oregon Health and Science University, Portland
| | - Nandita Gupta
- Knight Cardiovascular Institute (Q.E.D., B.A.H., S.A.C., N.G., J.Q.P.), Oregon Health and Science University, Portland
| | - Shirin O Hiatt
- School of Nursing (Q.E.D., M.R.D., S.O.H., M.E.M., K.W.-S.), Oregon Health and Science University, Portland
| | - Mary E Medysky
- School of Nursing (Q.E.D., M.R.D., S.O.H., M.E.M., K.W.-S.), Oregon Health and Science University, Portland
| | - Jonathan Q Purnell
- Knight Cardiovascular Institute (Q.E.D., B.A.H., S.A.C., N.G., J.Q.P.), Oregon Health and Science University, Portland
| | - Kerri Winters-Stone
- School of Nursing (Q.E.D., M.R.D., S.O.H., M.E.M., K.W.-S.), Oregon Health and Science University, Portland.,Knight Cancer Institute (K.W.-S.), Oregon Health and Science University, Portland
| | - Christopher S Lee
- Boston College William F. Connell School of Nursing, Chestnut Hill, MA (C.S.L.)
| |
Collapse
|
24
|
Denfeld QE, Faulkner KM, Davis MR, Habecker BA, Chien CV, Gelow JM, Mudd JO, Hiatt SO, Grady KL, Lee CS. Exploring gender differences in trajectories of clinical markers and symptoms after left ventricular assist device implantation. Eur J Cardiovasc Nurs 2021; 20:648-656. [PMID: 34080624 DOI: 10.1093/eurjcn/zvab032] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/22/2020] [Revised: 10/14/2020] [Accepted: 03/23/2021] [Indexed: 11/14/2022]
Abstract
AIMS Despite well-known gender differences in heart failure, it is unknown if clinical markers and symptoms differ between women and men after left ventricular assist device (LVAD) implantation. Our aim was to examine gender differences in trajectories of clinical markers (echocardiographic markers and plasma biomarkers) and symptoms from pre- to post-LVAD implantation. METHODS AND RESULTS This was a secondary analysis of data collected from a study of patients from pre- to 1, 3, and 6 months post-LVAD implantation. Data were collected on left ventricular internal end-diastolic diameter (LVIDd) and ejection fraction (LVEF), plasma N-terminal pro-B-type natriuretic peptide (NT-proBNP), and soluble suppressor of tumorigenicity (sST2). Physical and depressive symptoms were measured using the Heart Failure Somatic Perception Scale and Patient Health Questionnaire-9, respectively. Latent growth curve modelling was used to compare trajectories between women and men. The average age of the sample (n = 98) was 53.3 ± 13.8 years, and most were male (80.6%) and had non-ischaemic aetiology (65.3%). Pre-implantation, women had significantly narrower LVIDd (P < 0.001) and worse physical symptoms (P = 0.041) compared with men. Between pre- and 6 months post-implantation, women had an increase in plasma sST2 followed by a decrease, whereas men had an overall decrease (slope: P = 0.014; quadratic: P = 0.011). Between 1 and 6 months post-implantation, women had a significantly greater increase in LVEF (P = 0.045) but lesser decline in plasmoa NT-proBNP compared with men (P = 0.025). CONCLUSION Trajectories of clinical markers differed somewhat between women and men, but trajectories of symptoms were similar, indicating some physiologic but not symptomatic gender differences in response to LVAD.
Collapse
Affiliation(s)
- Quin E Denfeld
- School of Nursing, Oregon Health & Science University, SN-ORD, 3455 S.W. U.S. Veterans Hospital Road, Portland, OR 97239-2941, USA
| | - Kenneth M Faulkner
- William F. Connell School of Nursing, Boston College, Chestnut Hill, MA, USA
| | - Mary Roberts Davis
- School of Nursing, Oregon Health & Science University, SN-ORD, 3455 S.W. U.S. Veterans Hospital Road, Portland, OR 97239-2941, USA
| | - Beth A Habecker
- Knight Cardiovascular Institute, Oregon Health & Science University, Portland, OR, USA.,Department of Chemical Physiology & Biochemistry, Oregon Health & Science University, Portland, OR, USA
| | - Christopher V Chien
- Department of Medicine, Division of Cardiology, University of North Carolina, Chapel Hill, NC, USA
| | - Jill M Gelow
- Providence Heart & Vascular Institute, Portland, OR, USA
| | - James O Mudd
- Providence Sacred Heart Medical Center, Spokane, WA, USA
| | - Shirin O Hiatt
- School of Nursing, Oregon Health & Science University, SN-ORD, 3455 S.W. U.S. Veterans Hospital Road, Portland, OR 97239-2941, USA
| | - Kathleen L Grady
- Department of Surgery, Division of Cardiac Surgery, Northwestern University Feinberg School of Medicine, Chicago, IL, USA
| | - Christopher S Lee
- William F. Connell School of Nursing, Boston College, Chestnut Hill, MA, USA
| |
Collapse
|
25
|
vonderEmbse AN, Elmore SE, Jackson KB, Habecker BA, Manz KE, Pennell KD, Lein PJ, La Merrill MA. Developmental exposure to DDT or DDE alters sympathetic innervation of brown adipose in adult female mice. Environ Health 2021; 20:37. [PMID: 33794904 PMCID: PMC8017793 DOI: 10.1186/s12940-021-00721-2] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2020] [Accepted: 03/15/2021] [Indexed: 05/04/2023]
Abstract
BACKGROUND Exposure to the bioaccumulative pesticide dichlorodiphenyltrichloroethane (DDT) and its metabolite dichlorodiphenyldichloroethylene (DDE) has been associated with increased risk of insulin resistance and obesity in humans and experimental animals. These effects appear to be mediated by reduced brown adipose tissue (BAT) thermogenesis, which is regulated by the sympathetic nervous system. Although the neurotoxicity of DDT is well-established, whether DDT alters sympathetic innervation of BAT is unknown. We hypothesized that perinatal exposure to DDT or DDE promotes thermogenic dysfunction by interfering with sympathetic regulation of BAT thermogenesis. METHODS Pregnant C57BL/6 J mice were administered environmentally relevant concentrations of DDTs (p,p'-DDT and o,p'-DDT) or DDE (p,p'-DDE), 1.7 mg/kg and 1.31 mg/kg, respectively, from gestational day 11.5 to postnatal day 5 by oral gavage, and longitudinal body temperature was recorded in male and female offspring. At 4 months of age, metabolic parameters were measured in female offspring via indirect calorimetry with or without the β3 adrenergic receptor agonist, CL 316,243. Immunohistochemical and neurochemical analyses of sympathetic neurons innervating BAT were evaluated. RESULTS We observed persistent thermogenic impairment in adult female, but not male, mice perinatally exposed to DDTs or p,p'-DDE. Perinatal DDTs exposure significantly impaired metabolism in adult female mice, an effect rescued by treatment with CL 316,243 immediately prior to calorimetry experiments. Neither DDTs nor p,p'-DDE significantly altered BAT morphology or the concentrations of norepinephrine and its metabolite DHPG in the BAT of DDTs-exposed mice. However, quantitative immunohistochemistry revealed a 20% decrease in sympathetic axons innervating BAT in adult female mice perinatally exposed to DDTs, but not p,p'-DDE, and 48 and 43% fewer synapses in stellate ganglia of mice exposed to either DDTs or p,p'-DDE, respectively, compared to control. CONCLUSIONS These data demonstrate that perinatal exposure to DDTs or p,p'-DDE impairs thermogenesis by interfering with patterns of connectivity in sympathetic circuits that regulate BAT.
Collapse
Affiliation(s)
- Annalise N. vonderEmbse
- Department of Environmental Toxicology, University of California-Davis College of Agricultural and Environmental Sciences, One Shields Avenue, Davis, CA 95616 USA
- Department of Molecular Biosciences, University of California-Davis, School of Veterinary Medicine, 1089 Veterinary Medicine Drive, Davis, CA 95616 USA
| | - Sarah E. Elmore
- Department of Environmental Toxicology, University of California-Davis College of Agricultural and Environmental Sciences, One Shields Avenue, Davis, CA 95616 USA
- Present address: Office of Environmental Health Hazard Assessment, California EPA, Oakland, CA USA
| | - Kyle B. Jackson
- Department of Environmental Toxicology, University of California-Davis College of Agricultural and Environmental Sciences, One Shields Avenue, Davis, CA 95616 USA
- Integrative Genetics and Genomics Graduate Group, University of California-Davis, Davis, CA USA
| | - Beth A. Habecker
- Department of Chemical Physiology and Biochemistry, Oregon Health & Science University, 3181 SW Sam Jackson Park Road, Portland, OR 97239 USA
| | - Katherine E. Manz
- School of Engineering, Brown University, 184 Hope Street, Providence, RI 02912 USA
| | - Kurt D. Pennell
- School of Engineering, Brown University, 184 Hope Street, Providence, RI 02912 USA
| | - Pamela J. Lein
- Department of Molecular Biosciences, University of California-Davis, School of Veterinary Medicine, 1089 Veterinary Medicine Drive, Davis, CA 95616 USA
| | - Michele A. La Merrill
- Department of Environmental Toxicology, University of California-Davis College of Agricultural and Environmental Sciences, One Shields Avenue, Davis, CA 95616 USA
| |
Collapse
|
26
|
Tapa S, Wang L, Francis Stuart SD, Wang Z, Jiang Y, Habecker BA, Ripplinger CM. Adrenergic supersensitivity and impaired neural control of cardiac electrophysiology following regional cardiac sympathetic nerve loss. Sci Rep 2020; 10:18801. [PMID: 33139790 PMCID: PMC7608682 DOI: 10.1038/s41598-020-75903-y] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2020] [Accepted: 10/20/2020] [Indexed: 12/16/2022] Open
Abstract
Myocardial infarction (MI) can result in sympathetic nerve loss in the infarct region. However, the contribution of hypo-innervation to electrophysiological remodeling, independent from MI-induced ischemia and fibrosis, has not been comprehensively investigated. We present a novel mouse model of regional cardiac sympathetic hypo-innervation utilizing a targeted-toxin (dopamine beta-hydroxylase antibody conjugated to saporin, DBH-Sap), and measure resulting electrophysiological and Ca2+ handling dynamics. Five days post-surgery, sympathetic nerve density was reduced in the anterior left ventricular epicardium of DBH-Sap hearts compared to control. In Langendorff-perfused hearts, there were no differences in mean action potential duration (APD80) between groups; however, isoproterenol (ISO) significantly shortened APD80 in DBH-Sap but not control hearts, resulting in a significant increase in APD80 dispersion in the DBH-Sap group. ISO also produced spontaneous diastolic Ca2+ elevation in DBH-Sap but not control hearts. In innervated hearts, sympathetic nerve stimulation (SNS) increased heart rate to a lesser degree in DBH-Sap hearts compared to control. Additionally, SNS produced APD80 prolongation in the apex of control but not DBH-Sap hearts. These results suggest that hypo-innervated hearts have regional super-sensitivity to circulating adrenergic stimulation (ISO), while having blunted responses to SNS, providing important insight into the mechanisms of arrhythmogenesis following sympathetic nerve loss.
Collapse
Affiliation(s)
- Srinivas Tapa
- Department of Pharmacology, UC Davis School of Medicine, 2419B Tupper Hall, One Shields Ave, Davis, CA, 95616, USA
| | - Lianguo Wang
- Department of Pharmacology, UC Davis School of Medicine, 2419B Tupper Hall, One Shields Ave, Davis, CA, 95616, USA
| | - Samantha D Francis Stuart
- Department of Pharmacology, UC Davis School of Medicine, 2419B Tupper Hall, One Shields Ave, Davis, CA, 95616, USA
| | - Zhen Wang
- Department of Pharmacology, UC Davis School of Medicine, 2419B Tupper Hall, One Shields Ave, Davis, CA, 95616, USA
| | - Yanyan Jiang
- Department of Pharmacology, UC Davis School of Medicine, 2419B Tupper Hall, One Shields Ave, Davis, CA, 95616, USA
| | - Beth A Habecker
- Department of Chemical Physiology and Biochemistry, Oregon Health and Science University, Portland, OR, USA
| | - Crystal M Ripplinger
- Department of Pharmacology, UC Davis School of Medicine, 2419B Tupper Hall, One Shields Ave, Davis, CA, 95616, USA.
| |
Collapse
|
27
|
Affiliation(s)
- Beth A. Habecker
- Department of Chemical Physiology and Biochemistry, Oregon Health and Science University, Portland, Oregon
- Department of Anesthesiology and Perioperative Medicine, Oregon Health and Science University, Portland, Oregon
- Department of Medicine, Knight Cardiovascular Institute, Oregon Health and Science University, Portland, Oregon
| |
Collapse
|
28
|
Wang L, Olivas A, Francis Stuart SD, Tapa S, Blake MR, Woodward WR, Habecker BA, Ripplinger CM. Cardiac sympathetic nerve transdifferentiation reduces action potential heterogeneity after myocardial infarction. Am J Physiol Heart Circ Physiol 2020; 318:H558-H565. [PMID: 31975627 DOI: 10.1152/ajpheart.00412.2019] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Cardiac sympathetic nerves undergo cholinergic transdifferentiation following reperfused myocardial infarction (MI), whereby the sympathetic nerves release both norepinephrine (NE) and acetylcholine (ACh). The functional electrophysiological consequences of post-MI transdifferentiation have never been explored. We performed MI or sham surgery in wild-type (WT) mice and mice in which choline acetyltransferase was deleted from adult noradrenergic neurons [knockout (KO)]. Electrophysiological activity was assessed with optical mapping of action potentials (AP) and intracellular Ca2+ transients (CaT) in innervated Langendorff-perfused hearts. KO MI hearts had similar NE content but reduced ACh content compared with WT MI hearts (0.360 ± 0.074 vs. 0.493 ± 0.087 pmol/mg; KO, n = 6; WT, n = 4; P < 0.05). KO MI hearts also had higher basal ex vivo heart rates versus WT MI hearts (328.5 ± 35.3 vs. 247.4 ± 62.4 beats/min; KO, n = 8; WT, n = 6; P < 0.05). AP duration at 80% repolarization was significantly shorter in the remote and border zones of KO MI versus WT MI hearts, whereas AP durations (APDs) were similar in infarct regions. This APD heterogeneity resulted in increased APD dispersion in the KO MI versus WT MI hearts (11.9 ± 2.7 vs. 8.2 ± 2.3 ms; KO, n = 8; WT, n = 6; P < 0.05), which was eliminated with atropine. CaT duration at 80% and CaT alternans magnitude were similar between groups both with and without sympathetic nerve stimulation. These results indicate that cholinergic transdifferentiation following MI prolongs APD in the remote and border zone and reduces APD heterogeneity.NEW & NOTEWORTHY Cardiac sympathetic neurons undergo cholinergic transdifferentiation following myocardial infarction; however, the electrophysiological effects of corelease of norepinephrine and acetylcholine (ACh) have never been assessed. Using a mouse model in which choline acetyltransferase was deleted from adult noradrenergic neurons and optical mapping of innervated hearts, we found that corelease of ACh reduces dispersion of action potential duration, which may be antiarrhythmic.
Collapse
Affiliation(s)
- Lianguo Wang
- Department of Pharmacology, University of California, Davis, California
| | - Antoinette Olivas
- Department of Chemical Physiology and Biochemistry, Oregon Health and Science University, Portland, Oregon
| | | | - Srinivas Tapa
- Department of Pharmacology, University of California, Davis, California
| | - Matthew R Blake
- Department of Chemical Physiology and Biochemistry, Oregon Health and Science University, Portland, Oregon
| | - William R Woodward
- Department of Chemical Physiology and Biochemistry, Oregon Health and Science University, Portland, Oregon
| | - Beth A Habecker
- Department of Chemical Physiology and Biochemistry, Oregon Health and Science University, Portland, Oregon.,Department of Medicine and Knight Cardiovascular Institute, Oregon Health and Science University, Portland, Oregon
| | | |
Collapse
|
29
|
Bayles RG, Olivas A, Denfeld Q, Woodward WR, Fei SS, Gao L, Habecker BA. Publisher Correction: Transcriptomic and neurochemical analysis of the stellate ganglia in mice highlights sex differences. Sci Rep 2019; 9:9506. [PMID: 31239448 PMCID: PMC6592886 DOI: 10.1038/s41598-019-45211-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Abstract
A correction to this article has been published and is linked from the HTML version of this paper. The error has been fixed in the paper.
Collapse
Affiliation(s)
- R G Bayles
- Department of Physiology and Pharmacology, Oregon Health & Science University, Portland, Oregon, 97239, USA
| | - A Olivas
- Department of Physiology and Pharmacology, Oregon Health & Science University, Portland, Oregon, 97239, USA
| | - Q Denfeld
- Department of Physiology and Pharmacology, Oregon Health & Science University, Portland, Oregon, 97239, USA
| | - W R Woodward
- Department of Physiology and Pharmacology, Oregon Health & Science University, Portland, Oregon, 97239, USA
| | - S S Fei
- Biostatistics & Bioinformatics Core, Oregon National Primate Research Center, Oregon Health & Science University, Beaverton, OR, 97006, USA
| | - L Gao
- Biostatistics & Bioinformatics Core, Oregon National Primate Research Center, Oregon Health & Science University, Beaverton, OR, 97006, USA
| | - B A Habecker
- Department of Physiology and Pharmacology, Oregon Health & Science University, Portland, Oregon, 97239, USA.
| |
Collapse
|
30
|
Bayles RG, Tran J, Olivas A, Woodward WR, Fei SS, Gao L, Habecker BA. Sex differences in sympathetic gene expression and cardiac neurochemistry in Wistar Kyoto rats. PLoS One 2019; 14:e0218133. [PMID: 31194790 PMCID: PMC6564003 DOI: 10.1371/journal.pone.0218133] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2019] [Accepted: 05/26/2019] [Indexed: 11/30/2022] Open
Abstract
The stellate ganglia are the predominant source of sympathetic innervation to the heart. Remodeling of sympathetic nerves projecting to the heart has been observed in several cardiovascular diseases, and sympathetic dysfunction contributes to cardiac pathology. Wistar Kyoto rats are a common model for the study of cardiovascular diseases, but we lack a profile of the baseline transcriptomic and neurochemical characteristics of their cardiac sympathetic neurons. Most studies of cardiovascular disease have used male animals only, but in the future both male and female animals will be used for these types of studies; therefore, we sought to characterize the transcriptome of male and female stellate ganglia and to correlate that with catecholamine and acetylcholine content in the heart. We have generated a dataset of baseline RNA expression in male and female Wistar Kyoto rat stellate ganglia using RNA-seq, and have measured neurotransmitter levels in heart and stellate ganglia using HPLC and mass spectrometry. We identified numerous gene expression differences between male and female stellates, including genes encoding important developmental factors, receptors and neuropeptides. Female hearts had significantly higher neurotransmitter content than male hearts; however, no significant differences were detected in expression of the genes encoding neurotransmitter synthetic enzymes. Similarly, no statistically significant differences were identified between the sexes in cardiac tyrosine hydroxylase levels.
Collapse
Affiliation(s)
- Richard G. Bayles
- Department of Physiology and Pharmacology, Oregon Health & Science University, Portland, Oregon, United States of America
| | - Joanne Tran
- Department of Physiology and Pharmacology, Oregon Health & Science University, Portland, Oregon, United States of America
| | - Antoinette Olivas
- Department of Physiology and Pharmacology, Oregon Health & Science University, Portland, Oregon, United States of America
| | - William R. Woodward
- Department of Physiology and Pharmacology, Oregon Health & Science University, Portland, Oregon, United States of America
| | - Suzanne S. Fei
- Bioinformatics & Biostatistics Core, Oregon National Primate Research Center, Oregon Health & Science University, Beaverton, Oregon, United States of America
| | - Lina Gao
- Bioinformatics & Biostatistics Core, Oregon National Primate Research Center, Oregon Health & Science University, Beaverton, Oregon, United States of America
| | - Beth A. Habecker
- Department of Physiology and Pharmacology, Oregon Health & Science University, Portland, Oregon, United States of America
- * E-mail:
| |
Collapse
|
31
|
Francis Stuart SD, Wang L, Woodard WR, Ng GA, Habecker BA, Ripplinger CM. Age-related changes in cardiac electrophysiology and calcium handling in response to sympathetic nerve stimulation. J Physiol 2018; 596:3977-3991. [PMID: 29938794 DOI: 10.1113/jp276396] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2018] [Accepted: 06/22/2018] [Indexed: 12/16/2022] Open
Abstract
KEY POINTS Ageing results in changes to cardiac electrophysiology, Ca2+ handling, and β-adrenergic responsiveness. Sympathetic neurodegeneration also occurs with age, yet detailed action potential and Ca2+ handling responses to physiological sympathetic nerve stimulation (SNS) in the aged heart have not been assessed. Optical mapping in mouse hearts with intact sympathetic innervation revealed reduced responsiveness to SNS in the aged atria (assessed by heart rate) and aged ventricles (assessed by action potentials and Ca2+ transients). Sympathetic nerve density and noradrenaline content were reduced in aged ventricles, but noradrenaline content was preserved in aged atria. These results demonstrate that reduced responsiveness to SNS in the atria may be primarily due to decreased β-adrenergic receptor responsiveness, whereas reduced responsiveness to SNS in the ventricles may be primarily due to neurodegeneration. ABSTRACT The objective of this study was to determine how age-related changes in sympathetic structure and function impact cardiac electrophysiology and intracellular Ca2+ handling. Innervated hearts from young (3-4 months, YWT, n = 10) and aged (20-24 months, AGED, n = 11) female mice (C57Bl6) were optically mapped using the voltage (Vm ,)- and calcium (Ca2+ )-sensitive indicators Rh237 and Rhod2-AM. Sympathetic nerve stimulation (SNS) was performed at the spinal cord (T1-T3). β-Adrenergic responsiveness was assessed with isoproterenol (1 μM, ISO). Sympathetic nerve density and noradrenaline content were also quantified. Stimulation thresholds necessary to produce a defined increase in heart rate (HR) with SNS were higher in AGED vs. YWT hearts (5.4 ± 0.4 vs. 3.8 ± 0.4 Hz, P < 0.05). Maximal HR with SNS was lower in AGED vs. YWT (20.5 ± 3.41% vs. 73.0 ± 7.63% increase, P < 0.05). β-Adrenergic responsiveness of the atria (measured as percentage increase in HR with ISO) was decreased in AGED vs. YWT hearts (75.3 ± 22.5% vs. 148.5 ± 19.8%, P < 0.05). SNS significantly increased action potential duration (APD) in YWT but not AGED. Ca2+ transient durations and rise times were unchanged by SNS, yet AGED hearts had an increased susceptibility to Ca2+ alternans and ventricular arrhythmias. β-Adrenergic responsiveness of all ventricular parameters were similar between AGED and YWT. Sympathetic nerve density and noradrenaline content were decreased in the AGED ventricle, but not atria, compared to YWT. These data suggest that decreased responsiveness to SNS in the aged atria may be primarily due to decreased β-adrenergic responsiveness, whereas decreased responsiveness to SNS in the aged ventricles may be primarily due to nerve degeneration.
Collapse
Affiliation(s)
| | - Lianguo Wang
- Department of Pharmacology, University of California Davis, Davis, CA, USA
| | - William R Woodard
- Department of Physiology and Pharmacology, Oregon Health and Science University, Portland, OR, USA
| | - G Andre Ng
- Department of Cardiovascular Sciences, University of Leicester, NIHR Leicester Biomedical Research Centre, Leicester, UK
| | - Beth A Habecker
- Department of Physiology and Pharmacology, Oregon Health and Science University, Portland, OR, USA
| | | |
Collapse
|
32
|
Denfeld QE, Habecker BA, Woodward WR. Measurement of plasma norepinephrine and 3,4-dihydroxyphenylglycol: method development for a translational research study. BMC Res Notes 2018; 11:248. [PMID: 29673396 PMCID: PMC5909231 DOI: 10.1186/s13104-018-3352-3] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2018] [Accepted: 04/11/2018] [Indexed: 01/27/2023] Open
Abstract
Objective Norepinephrine (NE), a sympathetic neurotransmitter, is often measured in plasma as an index of sympathetic activity. To better understand NE dynamics, it is important to measure its principal metabolite, 3,4-dihydroxyphenylglycol (DHPG), concurrently. Our aim was to present a method, developed in the course of a translational research study, to measure NE and DHPG in human plasma using high performance liquid chromatography with electrochemical detection (HPLC-ED). Results After pre-purifying plasma samples by alumina extraction, we used HPLC-ED to separate and quantify NE and DHPG. In order to remove uric acid, which co-eluted with DHPG, a sodium bicarbonate wash was added to the alumina extraction procedure, and we oxidized the column eluates followed by reduction because catechols are reversibly oxidized whereas uric acid is irreversibly oxidized. Average recoveries of plasma NE and DHPG were 35.3 ± 1.0% and 16.3 ± 1.1%, respectively, and there was no detectable uric acid. Our estimated detection limits for NE and DHPG were approximately 85 pg/mL (0.5 pmol/mL) and 165 pg/mL (0.9 pmol/mL), respectively. The measurement of NE and DHPG in human plasma has wide applicability; thus, we describe a method to quantify plasma NE and DHPG in a laboratory setting as a useful tool for translational and clinical research. Electronic supplementary material The online version of this article (10.1186/s13104-018-3352-3) contains supplementary material, which is available to authorized users.
Collapse
Affiliation(s)
- Quin E Denfeld
- Knight Cardiovascular Institute, Oregon Health & Science University, Portland, OR, USA. .,Department of Physiology & Pharmacology, Oregon Health & Science University, Portland, OR, USA. .,School of Nursing, Oregon Health & Science University, 3455 S.W. U.S. Veterans Hospital Road, Mail code: SN-ORD, Portland, OR, 97239-2941, USA.
| | - Beth A Habecker
- Knight Cardiovascular Institute, Oregon Health & Science University, Portland, OR, USA.,Department of Physiology & Pharmacology, Oregon Health & Science University, Portland, OR, USA
| | - William R Woodward
- Department of Physiology & Pharmacology, Oregon Health & Science University, Portland, OR, USA.,Department of Neurology, Oregon Health & Science University, Portland, OR, USA
| |
Collapse
|
33
|
Francis Stuart SD, Wang L, Woodard WR, Habecker BA, Ripplinger CM. Age‐related changes in sympathetic responsiveness and cardiac electrophysiology. FASEB J 2018. [DOI: 10.1096/fasebj.2018.32.1_supplement.901.13] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
| | - Lianguo Wang
- PharmacologyUniversity of CaliforniaDavisDavisCA
| | - William R. Woodard
- Physiology and PharmacologyOregon Health and Science UniversityPortlandOR
| | - Beth A. Habecker
- Physiology and PharmacologyOregon Health and Science UniversityPortlandOR
| | | |
Collapse
|
34
|
Parrish DC, Francis Stuart SD, Olivas A, Wang L, Nykjaer A, Ripplinger CM, Habecker BA. Transient denervation of viable myocardium after myocardial infarction does not alter arrhythmia susceptibility. Am J Physiol Heart Circ Physiol 2018; 314:H415-H423. [PMID: 29101167 PMCID: PMC5899257 DOI: 10.1152/ajpheart.00300.2017] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/01/2017] [Revised: 10/30/2017] [Accepted: 10/30/2017] [Indexed: 01/14/2023]
Abstract
Cardiac sympathetic nerves stimulate heart rate and force of contraction. Myocardial infarction (MI) leads to the loss of sympathetic nerves within the heart, and clinical studies have indicated that sympathetic denervation is a risk factor for arrhythmias and cardiac arrest. Two distinct types of denervation have been identified in the mouse heart after MI caused by ischemia-reperfusion: transient denervation of peri-infarct myocardium and sustained denervation of the infarct. Sustained denervation is linked to increased arrhythmia risk, but it is not known whether acute nerve loss in peri-infarct myocardium also contributes to arrhythmia risk. Peri-infarct sympathetic denervation requires the p75 neurotrophin receptor (p75NTR), but removal of p75NTR alters the pattern of sympathetic innervation in the heart and increases spontaneous arrhythmias. Therefore, we targeted the p75NTR coreceptor sortilin and the p75NTR-induced protease tumor necrosis factor-α-converting enzyme/A disintegrin and metalloproteinase domain 17 (TACE/ADAM17) to selectively block peri-infarct denervation. Sympathetic nerve density was quantified using immunohistochemistry for tyrosine hydroxylase. Genetic deletion of sortilin had no effect on the timing or extent of axon degeneration, but inhibition of TACE/ADAM17 with the protease inhibitor marimastat prevented the loss of axons from viable myocardium. We then asked whether retention of nerves in peri-infarct myocardium had an impact on cardiac electrophysiology 3 days after MI using ex vivo optical mapping of transmembrane potential and intracellular Ca2+. Preventing acute denervation of viable myocardium after MI did not significantly alter cardiac electrophysiology or Ca2+ handling, suggesting that transient denervation at this early time point has minimal impact on arrhythmia risk. NEW & NOTEWORTHY Sympathetic denervation after myocardial infarction is a risk factor for arrhythmias. We asked whether transient loss of nerves in viable myocardium contributed to arrhythmia risk. We found that targeting protease activity could prevent acute peri-infarct denervation but that it did not significantly alter cardiac electrophysiology or Ca2+ handling 3 days after myocardial infarction.
Collapse
MESH Headings
- ADAM17 Protein/metabolism
- Action Potentials
- Adaptor Proteins, Vesicular Transport/metabolism
- Animals
- Arrhythmias, Cardiac/etiology
- Arrhythmias, Cardiac/metabolism
- Arrhythmias, Cardiac/pathology
- Arrhythmias, Cardiac/physiopathology
- Calcium Signaling
- Disease Models, Animal
- Heart/innervation
- Heart Rate
- Isolated Heart Preparation
- Mice, Inbred C57BL
- Mice, Knockout
- Myocardial Infarction/complications
- Myocardial Infarction/metabolism
- Myocardial Infarction/pathology
- Myocardial Infarction/physiopathology
- Myocardium/metabolism
- Myocardium/pathology
- Receptors, Nerve Growth Factor/deficiency
- Receptors, Nerve Growth Factor/genetics
- Sympathetic Nervous System/metabolism
- Sympathetic Nervous System/physiopathology
- Time Factors
- Tissue Survival
Collapse
Affiliation(s)
- Diana C Parrish
- Department of Physiology and Pharmacology, Oregon Health and Science University , Portland, Oregon
| | | | - Antoinette Olivas
- Department of Physiology and Pharmacology, Oregon Health and Science University , Portland, Oregon
| | - Lianguo Wang
- Department of Pharmacology, University of California , Davis, California
| | - Anders Nykjaer
- Department of Biomedicine-Medical Biochemistry, Aarhus University , Aarhus , Denmark
| | | | - Beth A Habecker
- Department of Physiology and Pharmacology, Oregon Health and Science University , Portland, Oregon
- Department of Medicine and Knight Cardiovascular Institute, Oregon Health and Science University , Portland, Oregon
| |
Collapse
|
35
|
Murphy SR, Wang L, Wang Z, Domondon P, Lang D, Habecker BA, Myles RC, Ripplinger CM. β-Adrenergic Inhibition Prevents Action Potential and Calcium Handling Changes during Regional Myocardial Ischemia. Front Physiol 2017; 8:630. [PMID: 28894423 PMCID: PMC5581400 DOI: 10.3389/fphys.2017.00630] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2017] [Accepted: 08/14/2017] [Indexed: 12/12/2022] Open
Abstract
β-adrenergic receptor (β-AR) blockers may be administered during acute myocardial infarction (MI), as they reduce energy demand through negative chronotropic and inotropic effects and prevent ischemia-induced arrhythmogenesis. However, the direct effects of β-AR blockers on ventricular electrophysiology and intracellular Ca2+ handling during ischemia remain unknown. Using optical mapping of transmembrane potential (with RH237) and sarcoplasmic reticulum (SR) Ca2+ (with the low-affinity indicator Fluo-5N AM), the effects of 15 min of regional ischemia were assessed in isolated rabbit hearts (n = 19). The impact of β-AR inhibition on isolated hearts was assessed by pre-treatment with 100 nM propranolol (Prop) prior to ischemia (n = 7). To control for chronotropy and inotropy, hearts were continuously paced at 3.3 Hz and contraction was inhibited with 20 μM blebbistatin. Untreated ischemic hearts displayed prototypical shortening of action potential duration (APD80) in the ischemic zone (IZ) compared to the non-ischemic zone (NI) at 10 and 15 min ischemia, whereas APD shortening was prevented with Prop. Untreated ischemic hearts also displayed significant changes in SR Ca2+ handling in the IZ, including prolongation of SR Ca2+ reuptake and SR Ca2+ alternans, which were prevented with Prop pre-treatment. At 5 min ischemia, Prop pre-treated hearts also showed larger SR Ca2+ release amplitude in the IZ compared to untreated hearts. These results suggest that even when controlling for chronotropic and inotropic effects, β-AR inhibition has a favorable effect during acute regional ischemia via direct effects on APD and Ca2+ handling.
Collapse
Affiliation(s)
- Shannon R Murphy
- Department of Pharmacology, University of California, DavisDavis, CA, United States
| | - Lianguo Wang
- Department of Pharmacology, University of California, DavisDavis, CA, United States
| | - Zhen Wang
- Department of Pharmacology, University of California, DavisDavis, CA, United States
| | - Philip Domondon
- Department of Biomedical Engineering, University of California, DavisDavis, CA, United States
| | - Di Lang
- Department of Pharmacology, University of California, DavisDavis, CA, United States
| | - Beth A Habecker
- Department of Physiology and Pharmacology, Oregon Health & Science UniversityPortland, OR, United States
| | - Rachel C Myles
- Institute of Cardiovascular and Medical Sciences, University of GlasgowGlasgow, United Kingdom
| | - Crystal M Ripplinger
- Department of Pharmacology, University of California, DavisDavis, CA, United States
| |
Collapse
|
36
|
Vaseghi M, Salavatian S, Rajendran PS, Yagishita D, Woodward WR, Hamon D, Yamakawa K, Irie T, Habecker BA, Shivkumar K. Parasympathetic dysfunction and antiarrhythmic effect of vagal nerve stimulation following myocardial infarction. JCI Insight 2017; 2:86715. [PMID: 28814663 DOI: 10.1172/jci.insight.86715] [Citation(s) in RCA: 54] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2016] [Accepted: 07/06/2017] [Indexed: 01/22/2023] Open
Abstract
Myocardial infarction causes sympathetic activation and parasympathetic dysfunction, which increase risk of sudden death due to ventricular arrhythmias. Mechanisms underlying parasympathetic dysfunction are unclear. The aim of this study was to delineate consequences of myocardial infarction on parasympathetic myocardial neurotransmitter levels and the function of parasympathetic cardiac ganglia neurons, and to assess electrophysiological effects of vagal nerve stimulation on ventricular arrhythmias in a chronic porcine infarct model. While norepinephrine levels decreased, cardiac acetylcholine levels remained preserved in border zones and viable myocardium of infarcted hearts. In vivo neuronal recordings demonstrated abnormalities in firing frequency of parasympathetic neurons of infarcted animals. Neurons that were activated by parasympathetic stimulation had low basal firing frequency, while neurons that were suppressed by left vagal nerve stimulation had abnormally high basal activity. Myocardial infarction increased sympathetic inputs to parasympathetic convergent neurons. However, the underlying parasympathetic cardiac neuronal network remained intact. Augmenting parasympathetic drive with vagal nerve stimulation reduced ventricular arrhythmia inducibility by decreasing ventricular excitability and heterogeneity of repolarization of infarct border zones, an area with known proarrhythmic potential. Preserved acetylcholine levels and intact parasympathetic neuronal pathways can explain the electrical stabilization of infarct border zones with vagal nerve stimulation, providing insight into its antiarrhythmic benefit.
Collapse
Affiliation(s)
- Marmar Vaseghi
- Cardiac Arrhythmia Center.,Neurocardiology Research Center of Excellence, and.,Molecular Cellular and Integrative Physiology Interdepartmental Program, UCLA, Los Angeles, California, USA
| | - Siamak Salavatian
- Cardiac Arrhythmia Center.,Neurocardiology Research Center of Excellence, and.,Molecular Cellular and Integrative Physiology Interdepartmental Program, UCLA, Los Angeles, California, USA
| | - Pradeep S Rajendran
- Cardiac Arrhythmia Center.,Neurocardiology Research Center of Excellence, and.,Molecular Cellular and Integrative Physiology Interdepartmental Program, UCLA, Los Angeles, California, USA
| | - Daigo Yagishita
- Cardiac Arrhythmia Center.,Neurocardiology Research Center of Excellence, and
| | | | - David Hamon
- Cardiac Arrhythmia Center.,Neurocardiology Research Center of Excellence, and
| | | | - Tadanobu Irie
- Cardiac Arrhythmia Center.,Neurocardiology Research Center of Excellence, and
| | - Beth A Habecker
- Department of Physiology & Pharmacology and.,Department of Medicine Knight Cardiovascular Institute, Oregon Health and Science University, Portland, Oregon, USA
| | - Kalyanam Shivkumar
- Cardiac Arrhythmia Center.,Neurocardiology Research Center of Excellence, and.,Molecular Cellular and Integrative Physiology Interdepartmental Program, UCLA, Los Angeles, California, USA
| |
Collapse
|
37
|
Sedaghat G, Gardner RT, Kabir MM, Ghafoori E, Habecker BA, Tereshchenko LG. Correlation between the high-frequency content of the QRS on murine surface electrocardiogram and the sympathetic nerves density in left ventricle after myocardial infarction: Experimental study. J Electrocardiol 2017; 50:323-331. [PMID: 28190561 DOI: 10.1016/j.jelectrocard.2017.01.014] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2016] [Indexed: 10/20/2022]
Abstract
Denervated post-infarct scar is arrhythmogenic. Our aim was to compare QRS frequency content in denervated and innervated left ventricular (LV) scar. In-vivo single lead ECG telemetry device was implanted in 17 heterozygous PTPσ (HET) and 7 lacking PTPσ (KO) transgenic mice. Myocardial infarction (MI) with reperfusion and sham surgery was performed. HET mice developed a denervated scar, whereas KO mice developed innervated scar. The power spectral density was used to assess the QRS frequency content. Denervated as compared to innervated post-MI scar was characterized by the higher relative contribution of 300-500 Hz (14 ± 1 vs. 9 ± 1%; P = 0.001) but reduced relative contribution of 200-300 Hz (86 ± 1 vs. 91 ± 1%; P = 0.001). Norepinephrine concentration in peri-infarct zone correlated with both 1-200 Hz (r = 0.75; P = 0.03) and 200-500 Hz QRS power (r = 0.73; P = 0.04). Sympathetic fiber density within the infarct correlated with 200-300/200-500 Hz QRS power ratio (r = 0.56; P = 0.005). Intracellular sigma peptide injections in post-MI HET mice restored the QRS power.
Collapse
Affiliation(s)
- Golriz Sedaghat
- Knight Cardiovascular Institute, Oregon Health & Science University, Portland, OR, USA; Portland State University, Portland, OR, USA
| | - Ryan T Gardner
- Department of Physiology and Pharmacology, Oregon Health and Science University, Portland, OR, USA
| | - Muammar M Kabir
- Knight Cardiovascular Institute, Oregon Health & Science University, Portland, OR, USA
| | - Elyar Ghafoori
- Knight Cardiovascular Institute, Oregon Health & Science University, Portland, OR, USA; University of Utah, Salt Lake City, UT, USA
| | - Beth A Habecker
- Department of Physiology and Pharmacology, Oregon Health and Science University, Portland, OR, USA
| | - Larisa G Tereshchenko
- Knight Cardiovascular Institute, Oregon Health & Science University, Portland, OR, USA.
| |
Collapse
|
38
|
Pinkham MI, Loftus MT, Amirapu S, Guild SJ, Quill G, Woodward WR, Habecker BA, Barrett CJ. Renal denervation in male rats with heart failure improves ventricular sympathetic nerve innervation and function. Am J Physiol Regul Integr Comp Physiol 2017; 312:R368-R379. [PMID: 28052866 DOI: 10.1152/ajpregu.00313.2016] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2016] [Revised: 12/14/2016] [Accepted: 01/02/2017] [Indexed: 01/19/2023]
Abstract
Heart failure is characterized by the loss of sympathetic innervation to the ventricles, contributing to impaired cardiac function and arrhythmogenesis. We hypothesized that renal denervation (RDx) would reverse this loss. Male Wistar rats underwent myocardial infarction (MI) or sham surgery and progressed into heart failure for 4 wk before receiving bilateral RDx or sham RDx. After additional 3 wk, left ventricular (LV) function was assessed, and ventricular sympathetic nerve fiber density was determined via histology. Post-MI heart failure rats displayed significant reductions in ventricular sympathetic innervation and tissue norepinephrine content (nerve fiber density in the LV of MI+sham RDx hearts was 0.31 ± 0.05% vs. 1.00 ± 0.10% in sham MI+sham RDx group, P < 0.05), and RDx significantly increased ventricular sympathetic innervation (0.76 ± 0.14%, P < 0.05) and tissue norepinephrine content. MI was associated with an increase in fibrosis of the noninfarcted ventricular myocardium, which was attenuated by RDx. RDx improved LV ejection fraction and end-systolic and -diastolic areas when compared with pre-RDx levels. This is the first study to show an interaction between renal nerve activity and cardiac sympathetic nerve innervation in heart failure. Our findings show denervating the renal nerves improves cardiac sympathetic innervation and function in the post-MI failing heart.
Collapse
Affiliation(s)
| | - Michael T Loftus
- Department of Physiology, University of Auckland, Auckland, New Zealand
| | - Satya Amirapu
- Department of Anatomy and Radiology, University of Auckland, Auckland, New Zealand
| | - Sarah-Jane Guild
- Department of Physiology, University of Auckland, Auckland, New Zealand
| | - Gina Quill
- Department of Medicine, University of Auckland, Auckland, New Zealand; and
| | - William R Woodward
- Department of Physiology and Pharmacology, Oregon Health & Science University, Portland, Oregon
| | - Beth A Habecker
- Department of Physiology and Pharmacology, Oregon Health & Science University, Portland, Oregon
| | - Carolyn J Barrett
- Department of Physiology, University of Auckland, Auckland, New Zealand
| |
Collapse
|
39
|
Affiliation(s)
- Olujimi A Ajijola
- UCLA Cardiac Arrhythmia Center and Neurocardiology Research Center, Los Angeles, CA, USA
| | - Kalyanam Shivkumar
- UCLA Cardiac Arrhythmia Center and Neurocardiology Research Center, Los Angeles, CA, USA
| | - Beth A Habecker
- Department of Physiology and Pharmacology, Department of Medicine Division of Cardiovascular Medicine and Knight Cardiovascular Institute, Oregon Health and Science University, Portland, OR, USA
| |
Collapse
|
40
|
Li BX, Gardner R, Xue C, Qian DZ, Xie F, Thomas G, Kazmierczak SC, Habecker BA, Xiao X. Systemic Inhibition of CREB is Well-tolerated in vivo. Sci Rep 2016; 6:34513. [PMID: 27694829 PMCID: PMC5046085 DOI: 10.1038/srep34513] [Citation(s) in RCA: 42] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2016] [Accepted: 09/15/2016] [Indexed: 11/30/2022] Open
Abstract
cAMP-response element binding protein (CREB) is a nuclear transcription factor activated by multiple extracellular signals including growth factors and hormones. These extracellular cues activate CREB through phosphorylation at Ser133 by various protein serine/threonine kinases. Once phosphorylated, it promotes its association with transcription coactivators CREB-binding protein (CBP) and its paralog p300 to activate CREB-dependent gene transcription. Tumor tissues of different origins have been shown to present overexpression and/or overactivation of CREB, indicating CREB as a potential cancer drug target. We previously identified 666-15 as a potent inhibitor of CREB with efficacious anti-cancer activity both in vitro and in vivo. Herein, we investigated the specificity of 666-15 and evaluated its potential in vivo toxicity. We found that 666-15 was fairly selective in inhibiting CREB. 666-15 was also found to be readily bioavailable to achieve pharmacologically relevant concentrations for CREB inhibition. Furthermore, the mice treated with 666-15 showed no evidence of changes in body weight, complete blood count, blood chemistry profile, cardiac contractility and tissue histologies from liver, kidney and heart. For the first time, these results demonstrate that pharmacological inhibition of CREB is well-tolerated in vivo and indicate that such inhibitors should be promising cancer therapeutics.
Collapse
Affiliation(s)
- Bingbing X Li
- Program in Chemical Biology, Department of Physiology and Pharmacology, Oregon Health &Science University, 3181 SW Sam Jackson Park Rd, Portland, OR 97239, USA
| | - Ryan Gardner
- Program in Chemical Biology, Department of Physiology and Pharmacology, Oregon Health &Science University, 3181 SW Sam Jackson Park Rd, Portland, OR 97239, USA
| | - Changhui Xue
- Knight Cancer Institute, Oregon Health &Science University, 3181 SW Sam Jackson Park Rd, Portland, OR 97239, USA
| | - David Z Qian
- Knight Cancer Institute, Oregon Health &Science University, 3181 SW Sam Jackson Park Rd, Portland, OR 97239, USA
| | - Fuchun Xie
- Program in Chemical Biology, Department of Physiology and Pharmacology, Oregon Health &Science University, 3181 SW Sam Jackson Park Rd, Portland, OR 97239, USA
| | - George Thomas
- Knight Cancer Institute, Oregon Health &Science University, 3181 SW Sam Jackson Park Rd, Portland, OR 97239, USA
| | - Steven C Kazmierczak
- Department of Pathology, Oregon Health &Science University, 3181 SW Sam Jackson Park Rd, Portland, OR 97239, USA
| | - Beth A Habecker
- Program in Chemical Biology, Department of Physiology and Pharmacology, Oregon Health &Science University, 3181 SW Sam Jackson Park Rd, Portland, OR 97239, USA.,Knight Cardiovascular Institute, Department of Medicine, Oregon Health &Science University, 3181 SW Sam Jackson Park Rd, Portland, OR 97239, USA
| | - Xiangshu Xiao
- Program in Chemical Biology, Department of Physiology and Pharmacology, Oregon Health &Science University, 3181 SW Sam Jackson Park Rd, Portland, OR 97239, USA.,Knight Cancer Institute, Oregon Health &Science University, 3181 SW Sam Jackson Park Rd, Portland, OR 97239, USA.,Knight Cardiovascular Institute, Department of Medicine, Oregon Health &Science University, 3181 SW Sam Jackson Park Rd, Portland, OR 97239, USA
| |
Collapse
|
41
|
Courter LA, Shaffo FC, Ghogha A, Parrish DJ, Lorentz CU, Habecker BA, Lein PJ. BMP7-induced dendritic growth in sympathetic neurons requires p75(NTR) signaling. Dev Neurobiol 2016; 76:1003-13. [PMID: 26663679 PMCID: PMC4905816 DOI: 10.1002/dneu.22371] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2015] [Revised: 10/26/2015] [Accepted: 12/09/2015] [Indexed: 12/29/2022]
Abstract
Dendritic morphology is a critical determinant of neuronal connectivity, and in postganglionic sympathetic neurons, tonic activity correlates directly with the size of the dendritic arbor. Thus, identifying signaling mechanisms that regulate dendritic arborization of sympathetic neurons is important to understanding how functional neural circuitry is established and maintained in the sympathetic nervous system. Bone morphogenetic proteins (BMPs) promote dendritic growth in sympathetic neurons; however, downstream signaling events that link BMP receptor activation to dendritic growth are poorly characterized. We previously reported that BMP7 upregulates p75(NTR) mRNA in cultured sympathetic neurons. This receptor is implicated in controlling dendritic growth in central neurons but whether p75(NTR) regulates dendritic growth in peripheral neurons is not known. Here, we demonstrate that BMP7 increases p75(NTR) protein in cultured sympathetic neurons, and this effect is blocked by pharmacologic inhibition of signaling via BMP type I receptor. BMP7 does not trigger dendritic growth in sympathetic neurons dissociated from superior cervical ganglia (SCG) of p75(NTR) nullizygous mice, and overexpression of p75(NTR) in p75(NTR) -/- neurons is sufficient to cause dendritic growth even in the absence of BMP7. Morphometric analyses of SCG from wild-type versus p75(NTR) nullizygous mice at 3, 6, and 12 to 16 weeks of age indicated that genetic deletion of p75(NTR) does not prevent dendritic growth but does stunt dendritic maturation in sympathetic neurons. These data support the hypotheses that p75(NTR) is involved in downstream signaling events that mediate BMP7-induced dendritic growth in sympathetic neurons, and suggest that p75(NTR) signaling positively modulates dendritic complexity in sympathetic neurons in vivo. © 2016 Wiley Periodicals, Inc. Develop Neurobiol 76: 1003-1013, 2016.
Collapse
Affiliation(s)
- Lauren A. Courter
- Center for Research on Occupational and Environmental Toxicology, Oregon Health & Science University, Portland, OR 97239
| | - Frances C. Shaffo
- Department of Molecular Biosciences, University of California, Davis, CA 95616
| | - Atefeh Ghogha
- Department of Molecular Biosciences, University of California, Davis, CA 95616
| | - Diana J. Parrish
- Department of Physiology and Pharmacology, Oregon Health & Science University, Portland, OR 97239
| | - Christina U. Lorentz
- Department of Physiology and Pharmacology, Oregon Health & Science University, Portland, OR 97239
| | - Beth A. Habecker
- Department of Physiology and Pharmacology, Oregon Health & Science University, Portland, OR 97239
| | - Pamela J. Lein
- Center for Research on Occupational and Environmental Toxicology, Oregon Health & Science University, Portland, OR 97239
- Department of Molecular Biosciences, University of California, Davis, CA 95616
| |
Collapse
|
42
|
Habecker BA, Anderson ME, Birren SJ, Fukuda K, Herring N, Hoover DB, Kanazawa H, Paterson DJ, Ripplinger CM. Molecular and cellular neurocardiology: development, and cellular and molecular adaptations to heart disease. J Physiol 2016; 594:3853-75. [PMID: 27060296 DOI: 10.1113/jp271840] [Citation(s) in RCA: 70] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2015] [Accepted: 03/15/2016] [Indexed: 12/12/2022] Open
Abstract
The nervous system and cardiovascular system develop in concert and are functionally interconnected in both health and disease. This white paper focuses on the cellular and molecular mechanisms that underlie neural-cardiac interactions during development, during normal physiological function in the mature system, and during pathological remodelling in cardiovascular disease. The content on each subject was contributed by experts, and we hope that this will provide a useful resource for newcomers to neurocardiology as well as aficionados.
Collapse
Affiliation(s)
- Beth A Habecker
- Department of Physiology and Pharmacology, Department of Medicine Division of Cardiovascular Medicine and Knight Cardiovascular Institute, Oregon Health and Science University, Portland, OR, 97239, USA
| | - Mark E Anderson
- Johns Hopkins Department of Medicine, Johns Hopkins School of Medicine, Baltimore, MD, 21287, USA
| | - Susan J Birren
- Department of Biology, Volen Center for Complex Systems, Brandeis University, Waltham, MA, 02453, USA
| | - Keiichi Fukuda
- Department of Cardiology, Keio University School of Medicine, 35-Shinanomachi, Shinjuku-ku, Tokyo, 160-8582, Japan
| | - Neil Herring
- Burdon Sanderson Cardiac Science Centre, Department of Physiology, Anatomy and Genetics, University of Oxford, Parks Road, Oxford, OX1 3PT, UK
| | - Donald B Hoover
- Department of Biomedical Sciences, Center of Excellence in Inflammation, Infectious Disease and Immunity, James H. Quillen College of Medicine, East Tennessee State University, Johnson City, TN, 37614, USA
| | - Hideaki Kanazawa
- Department of Cardiology, Keio University School of Medicine, 35-Shinanomachi, Shinjuku-ku, Tokyo, 160-8582, Japan
| | - David J Paterson
- Burdon Sanderson Cardiac Science Centre, Department of Physiology, Anatomy and Genetics, University of Oxford, Parks Road, Oxford, OX1 3PT, UK
| | | |
Collapse
|
43
|
Affiliation(s)
- Ryan T Gardner
- From the Department of Physiology and Pharmacology and Knight Cardiovascular Institute, Oregon Health and Science University, Portland (R.T.G., B.A.H.); Department of Pharmacology, School of Medicine, University of California, Davis (C.M.R.); and Institute of Cardiovascular and Medical Sciences, University of Glasgow, Glasgow, United Kingdom (R.C.M.)
| | - Crystal M Ripplinger
- From the Department of Physiology and Pharmacology and Knight Cardiovascular Institute, Oregon Health and Science University, Portland (R.T.G., B.A.H.); Department of Pharmacology, School of Medicine, University of California, Davis (C.M.R.); and Institute of Cardiovascular and Medical Sciences, University of Glasgow, Glasgow, United Kingdom (R.C.M.)
| | - Rachel C Myles
- From the Department of Physiology and Pharmacology and Knight Cardiovascular Institute, Oregon Health and Science University, Portland (R.T.G., B.A.H.); Department of Pharmacology, School of Medicine, University of California, Davis (C.M.R.); and Institute of Cardiovascular and Medical Sciences, University of Glasgow, Glasgow, United Kingdom (R.C.M.)
| | - Beth A Habecker
- From the Department of Physiology and Pharmacology and Knight Cardiovascular Institute, Oregon Health and Science University, Portland (R.T.G., B.A.H.); Department of Pharmacology, School of Medicine, University of California, Davis (C.M.R.); and Institute of Cardiovascular and Medical Sciences, University of Glasgow, Glasgow, United Kingdom (R.C.M.).
| |
Collapse
|
44
|
Obara Y, Nagasawa R, Nemoto W, Pellegrino MJ, Takahashi M, Habecker BA, Stork PJS, Ichiyanagi O, Ito H, Tomita Y, Ishii K, Nakahata N. ERK5 induces ankrd1 for catecholamine biosynthesis and homeostasis in adrenal medullary cells. Cell Signal 2015; 28:177-189. [PMID: 26739108 DOI: 10.1016/j.cellsig.2015.12.016] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2015] [Accepted: 12/24/2015] [Indexed: 01/04/2023]
Abstract
Extracellular signal-regulated kinases (ERKs) play important roles in proliferation, differentiation and gene expression. In our previous study, we demonstrated that both ERK5 and ERK1/2 were responsible for neurite outgrowth and tyrosine hydroxylase (TH) expression in rat pheochromocytoma cells (PC12) (J Biol Chem 284, 23,564-23,573, 2009). However, the functional differences between ERK5 and ERK1/2 signaling in neural differentiation remain unclear. In the present study, we show that ERK5, but not ERK1/2 regulates TH levels in rat sympathetic neurons. Furthermore, microarray analysis performed in PC12 cells using ERK5 and ERK1/2-specific inhibitors, identified ankyrin repeat domain 1 (ankrd1) as an ERK5-dependent and ERK1/2-independent gene. Here, we report a novel role of the ERK5/ankrd1 signaling in regulating TH levels and catecholamine biosynthesis. Ankrd1 mRNA was induced by nerve growth factor in time- and concentration-dependent manners. TH levels were reduced by ankrd1 knockdown with no changes in the mRNA levels, suggesting that ankrd1 was involved in stabilization of TH protein. Interestingly, ubiquitination of TH was enhanced and catecholamine biosynthesis was reduced by ankrd1 knockdown. Finally, we examined the relationship of ERK5 to TH levels in human adrenal pheochromocytomas. Whereas TH levels were correlated with ERK5 levels in normal adrenal medullas, ERK5 was down-regulated and TH was up-regulated in pheochromocytomas, indicating that TH levels are regulated by alternative mechanisms in tumors. Taken together, ERK5 signaling is required for catecholamine biosynthesis during neural differentiation, in part to induce ankrd1, and to maintain appropriate TH levels. This pathway is disrupted in pathological conditions.
Collapse
Affiliation(s)
- Yutaro Obara
- Department of Cellular Signaling, Graduate School of Pharmaceutical Sciences, Tohoku University, Aoba 6-3, Aramaki, Aoba-ku, Sendai 980-8578, Japan; Department of Pharmacology, Yamagata University School of Medicine, Iida-Nishi 2-2-2, Yamagata 990-9585, Japan.
| | - Ryusuke Nagasawa
- Department of Cellular Signaling, Graduate School of Pharmaceutical Sciences, Tohoku University, Aoba 6-3, Aramaki, Aoba-ku, Sendai 980-8578, Japan
| | - Wataru Nemoto
- Department of Cellular Signaling, Graduate School of Pharmaceutical Sciences, Tohoku University, Aoba 6-3, Aramaki, Aoba-ku, Sendai 980-8578, Japan
| | - Michael J Pellegrino
- Department of Physiology and Pharmacology, Oregon Health & Science University, 3181 SW Sam Jackson Park Road, Portland, OR 97239-3098, USA
| | - Maho Takahashi
- The Vollum Institute, Oregon Health & Science University, 3181 SW Sam Jackson Park Road, Portland, OR 97239-3098, USA
| | - Beth A Habecker
- Department of Physiology and Pharmacology, Oregon Health & Science University, 3181 SW Sam Jackson Park Road, Portland, OR 97239-3098, USA
| | - Philip J S Stork
- The Vollum Institute, Oregon Health & Science University, 3181 SW Sam Jackson Park Road, Portland, OR 97239-3098, USA
| | - Osamu Ichiyanagi
- Department of Urology, Yamagata University School of Medicine, Iida-Nishi 2-2-2, Yamagata 990-9585, Japan
| | - Hiromi Ito
- Department of Urology, Yamagata University School of Medicine, Iida-Nishi 2-2-2, Yamagata 990-9585, Japan
| | - Yoshihiko Tomita
- Department of Urology, Yamagata University School of Medicine, Iida-Nishi 2-2-2, Yamagata 990-9585, Japan
| | - Kuniaki Ishii
- Department of Pharmacology, Yamagata University School of Medicine, Iida-Nishi 2-2-2, Yamagata 990-9585, Japan
| | - Norimichi Nakahata
- Department of Cellular Signaling, Graduate School of Pharmaceutical Sciences, Tohoku University, Aoba 6-3, Aramaki, Aoba-ku, Sendai 980-8578, Japan
| |
Collapse
|
45
|
Melone MAB, Pellegrino MJ, Nolano M, Habecker BA, Johansson S, Nathanson NM, Knappskog PM, Hahn AF, Boman H. Unusual Stüve-Wiedemann syndrome with complete maternal chromosome 5 isodisomy. Ann Clin Transl Neurol 2014; 1:926-32. [PMID: 25540807 PMCID: PMC4265064 DOI: 10.1002/acn3.126] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2014] [Revised: 08/26/2014] [Accepted: 08/27/2014] [Indexed: 01/19/2023] Open
Abstract
A woman was isozygous for a novel mutation in the leukemia inhibitory factor receptor gene (LIFR) (c.2170C>G; p.Pro724Ala) which disrupts LIFR downstream signaling and results in Stüve-Wiedemann syndrome (STWS). She inherited two identical chromosomes 5 from her mother, heterozygous for the LIFR mutation. The presentation was typical for STWS, except there was no long bone dysplasia. Prominent cold-induced sweating and heat intolerance lead to an initial diagnosis of cold-induced sweating syndrome, excluded by exome sequencing. Skin biopsies provide the first human evidence of failed postnatal cholinergic differentiation of sympathetic neurons innervating sweat glands in cold-induced sweating, and of a neuropathy.
Collapse
Affiliation(s)
- Mariarosa A B Melone
- Division of Neurology and InterUniversity Center for Research in Neuroscience, Department of Clinical and Experimental Medicine and Surgery, Second University of Naples Naples, Italy
| | - Michael J Pellegrino
- Department of Physiology and Pharmacology, OHSU School of Medicine Portland, Oregon
| | - Maria Nolano
- Neurology Division, 'Salvatore Maugeri' Foundation IRCCS, Medical Center of Telese Terme Telese Terme, Benevento, Italy
| | - Beth A Habecker
- Department of Physiology and Pharmacology, OHSU School of Medicine Portland, Oregon
| | - Stefan Johansson
- Department of Clinical Science, University of Bergen Bergen, Norway ; Center of Medical Genetics and Molecular Medicine, Haukeland University Hospital Bergen, Norway
| | - Neil M Nathanson
- Department of Pharmacology, University of Washington Seattle, Washington
| | - Per M Knappskog
- Department of Clinical Science, University of Bergen Bergen, Norway ; Center of Medical Genetics and Molecular Medicine, Haukeland University Hospital Bergen, Norway
| | - Angelika F Hahn
- Department of Clinical Neurological Sciences, London Health Sciences Centre, Western University London, Ontario, Canada
| | - Helge Boman
- Department of Clinical Science, University of Bergen Bergen, Norway ; Center of Medical Genetics and Molecular Medicine, Haukeland University Hospital Bergen, Norway
| |
Collapse
|
46
|
Abstract
This chapter addresses the role of neurotrophins in the development of the heart, blood vessels, and neural circuits that control cardiovascular function, as well as the role of neurotrophins in the mature cardiovascular system. The cardiovascular system includes the heart and vasculature whose functions are tightly controlled by the nervous system. Neurons, cardiomyocytes, endothelial cells, vascular smooth muscle cells, and pericytes are all targets for neurotrophin action during development. Neurotrophin expression continues throughout life, and several common pathologies that impact cardiovascular function involve changes in the expression or activity of neurotrophins. These include atherosclerosis, hypertension, diabetes, acute myocardial infarction, and heart failure. In many of these conditions, altered expression of neurotrophins and/or neurotrophin receptors has direct effects on vascular endothelial and smooth muscle cells in addition to effects on nerves that modulate vascular resistance and cardiac function. This chapter summarizes the effects of neurotrophins in cardiovascular physiology and pathophysiology.
Collapse
Affiliation(s)
- Costanza Emanueli
- Regenerative Medicine Section, School of Clinical Sciences, Bristol Heart Institute, University of Bristol, Bristol, UK,
| | | | | | | |
Collapse
|
47
|
Pellegrino MJ, McCully BH, Habecker BA. Leptin stimulates sympathetic axon outgrowth. Neurosci Lett 2014; 566:1-5. [PMID: 24561183 DOI: 10.1016/j.neulet.2014.02.014] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/26/2013] [Revised: 01/27/2014] [Accepted: 02/07/2014] [Indexed: 12/28/2022]
Abstract
The neurohormone leptin regulates energy homeostasis. Circulating levels of leptin secreted by adipose tissue act on hypothalamic neurons in the brain leading to decreased appetite and increased energy expenditure. Although leptin signaling in the central nervous system (CNS) is fundamental to its ability to regulate the body's metabolic balance, leptin also has a variety of effects in many peripheral tissues including the heart, the liver, and the sympathetic nervous system. Leptin stimulation of the hypothalamus can stimulate glucose uptake via the sympathetic nervous system in heart, muscle, and brown adipose tissue. Leptin receptors (Ob-Rb) are also expressed by peripheral sympathetic neurons, but their functional role is not clear. In this study, we found that leptin stimulates axonal growth of both adult and neonatal sympathetic neurons in vitro. Leptin stimulates acute activation of the transcription factor STAT3 via phosphorylation of tyrosine 705. STAT3 phosphorylation is required for leptin-stimulated sympathetic axon outgrowth. Thus, circulating levels of leptin may enhance sympathetic nerve innervation of peripheral tissues.
Collapse
Affiliation(s)
- Michael J Pellegrino
- Department of Physiology and Pharmacology, Oregon Health & Science University, Portland, OR 97239, USA.
| | - Belinda H McCully
- Trauma Research Institute of Oregon, Division of Trauma, Critical Care & Acute Care Surgery, Department of Surgery, Oregon Health & Science University, Portland, OR 97239, USA.
| | - Beth A Habecker
- Department of Physiology and Pharmacology, Oregon Health & Science University, Portland, OR 97239, USA.
| |
Collapse
|
48
|
Lorentz CU, Parrish DC, Alston EN, Pellegrino MJ, Woodward WR, Hempstead BL, Habecker BA. Sympathetic denervation of peri-infarct myocardium requires the p75 neurotrophin receptor. Exp Neurol 2013; 249:111-9. [PMID: 24013014 PMCID: PMC3826885 DOI: 10.1016/j.expneurol.2013.08.015] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2013] [Revised: 08/23/2013] [Accepted: 08/27/2013] [Indexed: 12/22/2022]
Abstract
Development of cardiac sympathetic heterogeneity after myocardial infarction contributes to ventricular arrhythmias and sudden cardiac death. Regions of sympathetic hyperinnervation and denervation appear in the viable myocardium beyond the infarcted area. While elevated nerve growth factor (NGF) is implicated in sympathetic hyperinnervation, the mechanisms underlying denervation are unknown. Recent studies show that selective activation of the p75 neurotrophin receptor (p75(NTR)) in sympathetic neurons causes axon degeneration. We used mice that lack p75(NTR) to test the hypothesis that activation of p75(NTR) causes peri-infarct sympathetic denervation after cardiac ischemia-reperfusion. Wild type hearts exhibited sympathetic denervation adjacent to the infarct 24h and 3 days after ischemia-reperfusion, but no peri-infarct sympathetic denervation occurred in p75(NTR)-/- mice. Sympathetic hyperinnervation was found in the distal peri-infarct myocardium in both genotypes 3 days after MI, and hyperinnervation was increased in the p75(NTR)-/- mice. By 7 days after ischemia-reperfusion, cardiac sympathetic innervation density returned back to sham-operated levels in both genotypes, indicating that axonal pruning did not require p75(NTR). Prior studies revealed that proNGF is elevated in the damaged left ventricle after ischemia-reperfusion, as is mRNA encoding brain-derived neurotrophic factor (BDNF). ProNGF and BDNF preferentially bind p75(NTR) rather than TrkA on sympathetic neurons. Immunohistochemistry using Bdnf-HA mice confirmed the presence of BDNF or proBDNF in the infarct after ischemia-reperfusion. Thus, at least two p75(NTR) ligands are elevated in the left ventricle after ischemia-reperfusion where they may stimulate p75(NTR)-dependent denervation of peri-infarct myocardium. In contrast, NGF-induced sympathetic hyperinnervation in the distal peri-infarct ventricle is attenuated by p75(NTR).
Collapse
Affiliation(s)
- Christina U. Lorentz
- Department of Physiology and Pharmacology, Oregon Health and Science University, 3181 SW Sam Jackson Park Rd., Portland, Oregon 97239, USA
| | - Diana C. Parrish
- Department of Physiology and Pharmacology, Oregon Health and Science University, 3181 SW Sam Jackson Park Rd., Portland, Oregon 97239, USA
| | - Eric N. Alston
- Department of Physiology and Pharmacology, Oregon Health and Science University, 3181 SW Sam Jackson Park Rd., Portland, Oregon 97239, USA
| | - Michael J. Pellegrino
- Department of Physiology and Pharmacology, Oregon Health and Science University, 3181 SW Sam Jackson Park Rd., Portland, Oregon 97239, USA
| | - William R. Woodward
- Department of Neurology, Oregon Health and Science University, 3181 SW Sam Jackson Park Rd., Portland, Oregon 97239, USA
| | - Barbara L. Hempstead
- Division of Hematology and Medical Oncology, Department of Medicine, Weill Cornell Medical College, 1300 York Avenue, New York, NY 10065, USA
| | - Beth A. Habecker
- Department of Physiology and Pharmacology, Oregon Health and Science University, 3181 SW Sam Jackson Park Rd., Portland, Oregon 97239, USA
| |
Collapse
|
49
|
McCully BH, Hasan W, Streiff CT, Houle JC, Woodward WR, Giraud GD, Brooks VL, Habecker BA. Sympathetic cardiac hyperinnervation and atrial autonomic imbalance in diet-induced obesity promote cardiac arrhythmias. Am J Physiol Heart Circ Physiol 2013; 305:H1530-7. [PMID: 24014675 DOI: 10.1152/ajpheart.00196.2013] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Obesity increases the risk of arrhythmias and sudden cardiac death, but the mechanisms are unknown. This study tested the hypothesis that obesity-induced cardiac sympathetic outgrowth and hyperinnervation promotes the development of arrhythmic events. Male Sprague-Dawley rats (250-275 g), fed a high-fat diet (33% kcal/fat), diverged into obesity-resistant (OR) and obesity-prone (OP) groups and were compared with rats fed normal chow (13% kcal/fat; CON). In vitro experiments showed that both OR and OP rats exhibited hyperinnervation of the heart and high sympathetic outgrowth compared with CON rats, even though OR rats are not obese. Despite the hyperinnervation and outgrowth, we showed that, in vivo, OR rats were less susceptible to arrhythmic events after an intravenous epinephrine challenge compared with OP rats. On examining total and stimulus-evoked neurotransmitter levels in an ex vivo system, we demonstrate that atrial acetylcholine content and release were attenuated in OP compared with OR and CON groups. OP rats also expressed elevated atrial norepinephrine content, while norepinephrine release was suppressed. These findings suggest that the consumption of a high-fat diet, even in the absence of overt obesity, stimulates sympathetic outgrowth and hyperinnervation of the heart. However, normalized cardiac parasympathetic nervous system control may protect the heart from arrhythmic events.
Collapse
Affiliation(s)
- Belinda H McCully
- Department of Physiology and Pharmacology, Oregon Health & Science University, Portland, Oregon; and
| | | | | | | | | | | | | | | |
Collapse
|
50
|
Wehrwein EA, Novotny M, Swain GM, Parker LM, Esfahanian M, Spitsbergen JM, Habecker BA, Kreulen DL. Regional changes in cardiac and stellate ganglion norepinephrine transporter in DOCA-salt hypertension. Auton Neurosci 2013; 179:99-107. [PMID: 24075956 DOI: 10.1016/j.autneu.2013.08.070] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2013] [Revised: 08/21/2013] [Accepted: 08/26/2013] [Indexed: 11/19/2022]
Abstract
Uptake of norepinephrine via the neuronal norepinephrine transporter is reduced in the heart during deoxycorticosterone (DOCA)-salt hypertension. We hypothesized that this was due to reduced norepinephrine transporter mRNA and/or protein expression in the stellate ganglia and heart. After 4 weeks of DOCA-salt treatment there was no change in norepinephrine transporter mRNA in either the right or the left stellate ganglia from hypertensive rats (n=5-7, p>0.05). Norepinephrine transporter immunoreactivity in the left stellate ganglion was significantly increased (n=4, p<0.05) while the right stellate ganglion was unchanged (n=4, p>0.05). Whole heart norepinephrine content was significantly reduced in DOCA rats consistent with reduced uptake function; however, when norepinephrine was assessed by chamber, a significant decrease was noted only in the right atrium and right ventricle (n=6, p<0.05). Cardiac norepinephrine transport binding by chamber revealed that it was only reduced in the left atrium (n=5-7, p>0.05). Therefore, 1) contrary to our hypothesis reduced reuptake in the hypertensive heart is not exclusively due to an overall reduction in norepinephrine transporter mRNA or protein in the stellate ganglion or heart, and 2) norepinephrine transporter regulation occurs regionally in the heart and stellate ganglion in the hypertensive rat heart.
Collapse
Affiliation(s)
- Erica A Wehrwein
- Department of Physiology, Michigan State University, East Lansing, MI, United States.
| | | | | | | | | | | | | | | |
Collapse
|