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Singh J, Jackson KL, Tang FS, Fu T, Nowell C, Salimova E, Kiriazis H, Ritchie RH, Head GA, Woodman OL, Qin CX. The pro-resolving mediator, annexin A1 regulates blood pressure, and age-associated changes in cardiovascular function and remodeling. FASEB J 2024; 38:e23457. [PMID: 38318648 DOI: 10.1096/fj.202301802r] [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: 09/05/2023] [Revised: 12/21/2023] [Accepted: 01/18/2024] [Indexed: 02/07/2024]
Abstract
Aging is associated with chronic, low-level inflammation which may contribute to cardiovascular pathologies such as hypertension and atherosclerosis. This chronic inflammation may be opposed by endogenous mechanisms to limit inflammation, for example, by the actions of annexin A1 (ANXA1), an endogenous glucocorticoid-regulated protein that has anti-inflammatory and pro-resolving activity. We hypothesized the pro-resolving mediator ANXA1 protects against age-induced changes in blood pressure (BP), cardiovascular structure and function, and cardiac senescence. BP was measured monthly in conscious mature (4-month) and middle-aged (12-month) ANXA1-deficient (ANXA1-/- ) and wild-type C57BL/6 mice. Body composition was measured using EchoMRI, and both cardiac and vascular function using ultrasound imaging. Cardiac hypertrophy, fibrosis and senescence, vascular fibrosis, elastin, and calcification were assessed histologically. Gene expression relevant to structural remodeling, inflammation, and cardiomyocyte senescence were also quantified. In C57BL/6 mice, progression from 4 to 12 months of age did not affect the majority of cardiovascular parameters measured, with the exception of mild cardiac hypertrophy, vascular calcium, and collagen deposition. Interestingly, ANXA1-/- mice exhibited higher BP, regardless of age. Additionally, age progression had a marked impact in ANXA1-/- mice, with markedly augmented vascular remodeling, impaired vascular distensibility, and body composition. Consistent with vascular dysfunction, cardiac dysfunction, and hypertrophy were also evident, together with markers of senescence and inflammation. These findings suggest that endogenous ANXA1 plays a critical role in regulating BP, cardiovascular function, and remodeling and delays cardiac senescence. Our findings support the development of novel ANXA1-based therapies to prevent age-related cardiovascular pathologies.
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Affiliation(s)
- Jaideep Singh
- Drug Discovery Biology, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, Victoria, Australia
- Baker Heart & Diabetes Institute, Melbourne, Victoria, Australia
| | - Kristy L Jackson
- Drug Discovery Biology, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, Victoria, Australia
- Baker Heart & Diabetes Institute, Melbourne, Victoria, Australia
| | - Feng Shii Tang
- Drug Discovery Biology, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, Victoria, Australia
| | - Ting Fu
- Drug Discovery Biology, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, Victoria, Australia
| | - Cameron Nowell
- Drug Discovery Biology, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, Victoria, Australia
| | - Ekaterina Salimova
- Monash Biomedical Imaging, Monash University, Clayton, Melbourne, Victoria, Australia
| | - Helen Kiriazis
- Baker Heart & Diabetes Institute, Melbourne, Victoria, Australia
- Department of Cardiometabolic Health, University of Melbourne, Melbourne, Victoria, Australia
| | - Rebecca H Ritchie
- Drug Discovery Biology, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, Victoria, Australia
- Baker Heart & Diabetes Institute, Melbourne, Victoria, Australia
- Department of Cardiometabolic Health, University of Melbourne, Melbourne, Victoria, Australia
| | - Geoffrey A Head
- Baker Heart & Diabetes Institute, Melbourne, Victoria, Australia
| | - Owen L Woodman
- Drug Discovery Biology, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, Victoria, Australia
| | - Cheng Xue Qin
- Drug Discovery Biology, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, Victoria, Australia
- Baker Heart & Diabetes Institute, Melbourne, Victoria, Australia
- Department of Pharmacology, School of Pharmaceutical Sciences, Qilu College of Medicine, Shandong University, Jinan, China
- Department of Emergency Medicine, Qilu Hospital of Shandong University, Jinan, China
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Sharma A, Choi JSY, Watson AMD, Li L, Sonntag T, Lee MKS, Murphy AJ, De Blasio M, Head GA, Ritchie RH, de Haan JB. Cardiovascular characterisation of a novel mouse model that combines hypertension and diabetes co-morbidities. Sci Rep 2023; 13:8741. [PMID: 37253814 DOI: 10.1038/s41598-023-35680-w] [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] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2022] [Accepted: 05/22/2023] [Indexed: 06/01/2023] Open
Abstract
Epidemiologic data suggest that the prevalence of hypertension in patients with diabetes mellitus is ∼1.5-2.0 times greater than in matched non-diabetic patients. This co-existent disease burden exacerbates cardiac and vascular injury, leading to structural and functional changes to the myocardium, impaired cardiac function and heart failure. Oxidative stress and persistent low-grade inflammation underlie both conditions, and are identified as major contributors to pathological cardiac remodelling. There is an urgent need for effective therapies that specifically target oxidative stress and inflammation to protect against cardiac remodelling. Animal models are a valuable tool for testing emerging therapeutics, however, there is a notable lack of appropriate animal models of co-morbid diabetes and hypertension. In this study, we describe a novel preclinical mouse model combining diabetes and hypertension to investigate cardiac and vascular pathology of co-morbid disease. Type 1 diabetes was induced in spontaneously hypertensive, 8-week old, male Schlager (BPH/2) mice via 5 consecutive, daily injections of streptozotocin (55 mg/kg in citrate buffer; i.p.). Non-diabetic mice received citrate buffer only. After 10 weeks of diabetes induction, cardiac function was assessed by echocardiography prior to post-mortem evaluation of cardiomyocyte hypertrophy, interstitial fibrosis and inflammation by histology, RT-PCR and flow cytometry. We focussed on the oxidative and inflammatory stress pathways that contribute to cardiovascular remodelling. In particular, we demonstrate that markers of inflammation (monocyte chemoattractant protein; MCP-1), oxidative stress (urinary 8-isoprostanes) and fibrosis (connective tissue growth factor; CTGF) are significantly increased, whilst diastolic dysfunction, as indicated by prolonged isovolumic relaxation time (IVRT), is elevated in this diabetic and hypertensive mouse model. In summary, this pre-clinical mouse model provides researchers with a tool to test therapeutic strategies unique to co-morbid diabetes and hypertension, thereby facilitating the emergence of novel therapeutics to combat the cardiovascular consequences of these debilitating co-morbidities.
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Affiliation(s)
- Arpeeta Sharma
- Group Leader (Oxidative Stress Laboratory), Diabetic Complications Division, Baker Heart and Diabetes Institute, 75 Commercial Road, Melbourne, VIC, 3004, Australia.
- Department of Diabetes, Central Clinical School, Monash University, Melbourne, VIC, Australia.
| | - Judy S Y Choi
- Group Leader (Oxidative Stress Laboratory), Diabetic Complications Division, Baker Heart and Diabetes Institute, 75 Commercial Road, Melbourne, VIC, 3004, Australia
| | - Anna M D Watson
- Group Leader (Oxidative Stress Laboratory), Diabetic Complications Division, Baker Heart and Diabetes Institute, 75 Commercial Road, Melbourne, VIC, 3004, Australia
- Department of Diabetes, Central Clinical School, Monash University, Melbourne, VIC, Australia
- Department of Cardiometabolic Health, University of Melbourne, Parkville, Australia
| | - Leila Li
- Group Leader (Oxidative Stress Laboratory), Diabetic Complications Division, Baker Heart and Diabetes Institute, 75 Commercial Road, Melbourne, VIC, 3004, Australia
| | - Thomas Sonntag
- Group Leader (Oxidative Stress Laboratory), Diabetic Complications Division, Baker Heart and Diabetes Institute, 75 Commercial Road, Melbourne, VIC, 3004, Australia
| | - Man K S Lee
- Group Leader (Oxidative Stress Laboratory), Diabetic Complications Division, Baker Heart and Diabetes Institute, 75 Commercial Road, Melbourne, VIC, 3004, Australia
| | - Andrew J Murphy
- Group Leader (Oxidative Stress Laboratory), Diabetic Complications Division, Baker Heart and Diabetes Institute, 75 Commercial Road, Melbourne, VIC, 3004, Australia
| | - Miles De Blasio
- Drug Discovery Biology, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, VIC, Australia
| | - Geoffrey A Head
- Group Leader (Oxidative Stress Laboratory), Diabetic Complications Division, Baker Heart and Diabetes Institute, 75 Commercial Road, Melbourne, VIC, 3004, Australia
| | - Rebecca H Ritchie
- Group Leader (Oxidative Stress Laboratory), Diabetic Complications Division, Baker Heart and Diabetes Institute, 75 Commercial Road, Melbourne, VIC, 3004, Australia
- Drug Discovery Biology, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, VIC, Australia
| | - Judy B de Haan
- Group Leader (Oxidative Stress Laboratory), Diabetic Complications Division, Baker Heart and Diabetes Institute, 75 Commercial Road, Melbourne, VIC, 3004, Australia
- Department of Immunology and Pathology, Central Clinical School, Monash University, Melbourne, VIC, Australia
- Department of Physiology, Anatomy and Microbiology, La Trobe University, Melbourne, Australia
- Faculty of Science, Engineering and Technology, Swinburne University, Melbourne, Australia
- Department of Cardiometabolic Health, University of Melbourne, Parkville, Australia
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3
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Pearson JT, Phillips JK, Head GA. Editorial: Insights in integrative physiology: 2022. Front Physiol 2023; 14:1220684. [PMID: 37304816 PMCID: PMC10247965 DOI: 10.3389/fphys.2023.1220684] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2023] [Accepted: 05/18/2023] [Indexed: 06/13/2023] Open
Affiliation(s)
- James T. Pearson
- National Cerebral and Cardiovascular Center, Suita, Japan
- Department of Physiology, Victoria Heart Institute and Monash Biomedicine Discovery Institute, Monash University, Clayton, VIC, Australia
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Jelinic M, Jackson KL, O'Sullivan K, Singh J, Giddy T, Deo M, Parry LJ, Ritchie RH, Woodman OL, Head GA, Leo CH, Qin CX. Endothelium-dependent relaxation is impaired in Schlager hypertensive (BPH/2J) mice by region-specific mechanisms in conductance and resistance arteries. Life Sci 2023; 320:121542. [PMID: 36871935 DOI: 10.1016/j.lfs.2023.121542] [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] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2022] [Revised: 02/21/2023] [Accepted: 02/27/2023] [Indexed: 03/07/2023]
Abstract
AIMS Endothelial dysfunction and arterial stiffness are hallmarks of hypertension, and major risk factors for cardiovascular disease. BPH/2J (Schlager) mice are a genetic model of spontaneous hypertension, but little is known about the vascular pathophysiology of these mice and the region-specific differences between vascular beds. Therefore, this study compared the vascular function and structure of large conductance (aorta and femoral) and resistance (mesenteric) arteries of BPH/2J mice with their normotensive BPN/2J counterparts. MAIN METHODS Blood pressure was measured in BPH/2J and BPN/3J mice via pre-implanted radiotelemetry probes. At endpoint, vascular function and passive mechanical wall properties were assessed using wire and pressure myography, qPCR and histology. KEY FINDINGS Mean arterial blood pressure was elevated in BPH/2J mice compared to BPN/3J controls. Endothelium-dependent relaxation to acetylcholine was attenuated in both the aorta and mesenteric arteries of BPH/2J mice, but through different mechanisms. In the aorta, hypertension reduced the contribution of prostanoids. Conversely, in the mesenteric arteries, hypertension reduced the contribution of both nitric oxide and endothelium-dependent hyperpolarization. Hypertension reduced volume compliance in both femoral and mesenteric arteries, but hypertrophic inward remodelling was only observed in the mesenteric arteries of BPH/2J mice. SIGNIFICANCE This is the first comprehensive investigation of vascular function and structural remodelling in BPH/2J mice. Overall, hypertensive BPH/2J mice exhibited endothelial dysfunction and adverse vascular remodelling in the macro- and microvasculature, underpinned by distinct region-specific mechanisms. This highlights BPH/2J mice as a highly suitable model for evaluating novel therapeutics to treat hypertension-associated vascular dysfunction.
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Affiliation(s)
- Maria Jelinic
- Centre for Cardiovascular Biology and Disease Research, Department of Microbiology, Anatomy, Physiology & Pharmacology, La Trobe University, Bundoora, VIC, Australia; School of BioSciences, The University of Melbourne, Parkville, VIC, Australia
| | - Kristy L Jackson
- Baker Heart and Diabetes Research Institute, Melbourne, VIC, Australia; Faculty of Pharmacy and Pharmaceutical Sciences, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, VIC, Australia
| | - Kelly O'Sullivan
- School of BioSciences, The University of Melbourne, Parkville, VIC, Australia
| | - Jaideep Singh
- Baker Heart and Diabetes Research Institute, Melbourne, VIC, Australia; Faculty of Pharmacy and Pharmaceutical Sciences, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, VIC, Australia
| | - Thomas Giddy
- Baker Heart and Diabetes Research Institute, Melbourne, VIC, Australia
| | - Minh Deo
- Baker Heart and Diabetes Research Institute, Melbourne, VIC, Australia; Faculty of Pharmacy and Pharmaceutical Sciences, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, VIC, Australia
| | - Laura J Parry
- School of BioSciences, The University of Melbourne, Parkville, VIC, Australia; School of Biological Sciences, The University of Adelaide, Adelaide, SA, Australia
| | - Rebecca H Ritchie
- Baker Heart and Diabetes Research Institute, Melbourne, VIC, Australia; Faculty of Pharmacy and Pharmaceutical Sciences, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, VIC, Australia
| | - Owen L Woodman
- Faculty of Pharmacy and Pharmaceutical Sciences, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, VIC, Australia
| | - Geoffrey A Head
- Baker Heart and Diabetes Research Institute, Melbourne, VIC, Australia
| | - Chen Huei Leo
- School of BioSciences, The University of Melbourne, Parkville, VIC, Australia; Faculty of Pharmacy and Pharmaceutical Sciences, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, VIC, Australia; Science, Math and Technology, Singapore University of Technology & Design, Singapore.
| | - Cheng Xue Qin
- Baker Heart and Diabetes Research Institute, Melbourne, VIC, Australia; Faculty of Pharmacy and Pharmaceutical Sciences, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, VIC, Australia.
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Parati G, Bilo G, Kollias A, Pengo M, Ochoa JE, Castiglioni P, Stergiou GS, Mancia G, Asayama K, Asmar R, Avolio A, Caiani EG, De La Sierra A, Dolan E, Grillo A, Guzik P, Hoshide S, Head GA, Imai Y, Juhanoja E, Kahan T, Kario K, Kotsis V, Kreutz R, Kyriakoulis KG, Li Y, Manios E, Mihailidou AS, Modesti PA, Omboni S, Palatini P, Persu A, Protogerou AD, Saladini F, Salvi P, Sarafidis P, Torlasco C, Veglio F, Vlachopoulos C, Zhang Y. Blood pressure variability: methodological aspects, clinical relevance and practical indications for management - a European Society of Hypertension position paper ∗. J Hypertens 2023; 41:527-544. [PMID: 36723481 DOI: 10.1097/hjh.0000000000003363] [Citation(s) in RCA: 30] [Impact Index Per Article: 30.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
Blood pressure is not a static parameter, but rather undergoes continuous fluctuations over time, as a result of the interaction between environmental and behavioural factors on one side and intrinsic cardiovascular regulatory mechanisms on the other side. Increased blood pressure variability (BPV) may indicate an impaired cardiovascular regulation and may represent a cardiovascular risk factor itself, having been associated with increased all-cause and cardiovascular mortality, stroke, coronary artery disease, heart failure, end-stage renal disease, and dementia incidence. Nonetheless, BPV was considered only a research issue in previous hypertension management guidelines, because the available evidence on its clinical relevance presents several gaps and is based on heterogeneous studies with limited standardization of methods for BPV assessment. The aim of this position paper, with contributions from members of the European Society of Hypertension Working Group on Blood Pressure Monitoring and Cardiovascular Variability and from a number of international experts, is to summarize the available evidence in the field of BPV assessment methodology and clinical applications and to provide practical indications on how to measure and interpret BPV in research and clinical settings based on currently available data. Pending issues and clinical and methodological recommendations supported by available evidence are also reported. The information provided by this paper should contribute to a better standardization of future studies on BPV, but should also provide clinicians with some indications on how BPV can be managed based on currently available data.
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Affiliation(s)
- Gianfranco Parati
- Istituto Auxologico Italiano, IRCCS, Department of Cardiovascular Neural and Metabolic Sciences, Milan
- Department of Medicine and Surgery, University of Milano-Bicocca, Milan, Italy
| | - Grzegorz Bilo
- Istituto Auxologico Italiano, IRCCS, Department of Cardiovascular Neural and Metabolic Sciences, Milan
- Department of Medicine and Surgery, University of Milano-Bicocca, Milan, Italy
| | - Anastasios Kollias
- Hypertension Center STRIDE-7, National and Kapodistrian University of Athens, School of Medicine, Third Department of Medicine, Sotiria Hospital, Athens, Greece
| | - Martino Pengo
- Istituto Auxologico Italiano, IRCCS, Department of Cardiovascular Neural and Metabolic Sciences, Milan
- Department of Medicine and Surgery, University of Milano-Bicocca, Milan, Italy
| | - Juan Eugenio Ochoa
- Istituto Auxologico Italiano, IRCCS, Department of Cardiovascular Neural and Metabolic Sciences, Milan
| | - Paolo Castiglioni
- IRCCS Fondazione Don Carlo Gnocchi, Milan
- Department of Biotechnology and Life Sciences (DBSV), University of Insubria, Varese
| | - George S Stergiou
- Hypertension Center STRIDE-7, National and Kapodistrian University of Athens, School of Medicine, Third Department of Medicine, Sotiria Hospital, Athens, Greece
| | | | - Kei Asayama
- Department of Hygiene and Public Health, Teikyo University School of Medicine, Tokyo, Japan
- Department of Cardiovascular Sciences, University of Leuven, and Research Unit Hypertension and Cardiovascular Epidemiology, KU Leuven, Belgium
- Tohoku Institute for the Management of Blood Pressure, Sendai, Japan
| | - Roland Asmar
- Foundation-Medical Research Institutes, Geneva, Switzerland
| | - Alberto Avolio
- Department of Biomedical Sciences, Faculty of Medicine and Health Sciences, Macquarie University, Sydney, NSW, Australia
| | - Enrico G Caiani
- Istituto Auxologico Italiano, IRCCS, Department of Cardiovascular Neural and Metabolic Sciences, Milan
- Department of Electronics, Information, and Bioengineering, Politecnico di Milano, Italy
| | - Alejandro De La Sierra
- Hypertension Unit, Department of Internal Medicine, Hospital Mútua Terrassa, University of Barcelona, Barcelona, Spain
| | | | - Andrea Grillo
- Department of Medicine, Surgery and Health Sciences, University of Trieste, Italy
| | - Przemysław Guzik
- Department of Cardiology -Intensive Therapy, University School of Medicine in Poznan, Poznan, Poland
| | - Satoshi Hoshide
- Division of Cardiovascular Medicine, Department of Medicine, Jichi Medical University School of Medicine, Tochigi, Japan
| | - Geoffrey A Head
- Baker Heart and Diabetes Institute, Melbourne Victoria Australia
| | - Yutaka Imai
- Tohoku Institute for the Management of Blood Pressure, Sendai, Japan
| | - Eeva Juhanoja
- Chronic Disease Prevention Unit, National Institute for Health and Welfare, Turku
- Department of Oncology; Division of Medicine, Turku University Hospital, University of Turku, Turku, Finland
| | - Thomas Kahan
- Karolinska Institute, Department of Clinical Sciences, Division of Cardiovascular Medicine, Department of Cardiology, Danderyd University Hospital Corporation, Stockholm, Sweden
| | - Kazuomi Kario
- Division of Cardiovascular Medicine, Department of Medicine, Jichi Medical University School of Medicine, Tochigi, Japan
| | | | | | - Konstantinos G Kyriakoulis
- Hypertension Center STRIDE-7, National and Kapodistrian University of Athens, School of Medicine, Third Department of Medicine, Sotiria Hospital, Athens, Greece
| | - Yan Li
- Department of Cardiovascular Medicine, Shanghai Key Laboratory of Hypertension and Medical Genomics, National Research Centre for Translational Medicine
- Shanghai Institute of Hypertension, Ruijin Hospital, Shanghai Jiaotong University School of Medicine, Shanghai, China
| | - Efstathios Manios
- Department of Clinical Therapeutics, National and Kapodistrian University of Athens, School of Medicine, Alexandra Hospital Athens, Greece
| | - Anastasia S Mihailidou
- Department of Cardiology and Kolling Institute, Royal North Shore Hospital, St Leonards; Faculty of Medicine and Health Sciences, Macquarie University, Sydney, Australia
| | | | - Stefano Omboni
- Clinical Research Unit, Italian Institute of Telemedicine, Varese, Italy
- Department of Cardiology, Sechenov First Moscow State Medical University, Moscow, Russian Federation
| | - Paolo Palatini
- Department of Medicine. University of Padova, Padua, Italy
| | - Alexandre Persu
- Division of Cardiology, Department of Cardiovascular Diseases, Cliniques Universitaires Saint-Luc and Pole of Cardiovascular Research, Institut de Recherche Expérimentale et Clinique, Université Catholique de Louvain, Brussels, Belgium
| | - Athanasios D Protogerou
- Cardiovascular Prevention and Research Unit, Department of Pathophysiology, Medical School, National and Kapodistrian University of Athens, Laiko General Hospital, Athens, Greece
| | - Francesca Saladini
- Department of Medicine. University of Padova, Padua, Italy
- Cardiology Unit, Cittadella Town Hospital, Padova, Italy
| | - Paolo Salvi
- Istituto Auxologico Italiano, IRCCS, Department of Cardiovascular Neural and Metabolic Sciences, Milan
| | - Pantelis Sarafidis
- Department of Nephrology, Hippokration Hospital, Aristotle University of Thessaloniki, Greece
| | - Camilla Torlasco
- Istituto Auxologico Italiano, IRCCS, Department of Cardiovascular Neural and Metabolic Sciences, Milan
| | - Franco Veglio
- Internal Medicine Division and Hypertension Unit, Department of Medical Sciences, University of Turin, Turin, Italy
| | - Charalambos Vlachopoulos
- Hypertension and Cardiometabolic Syndrome Unit, 1 Department of Cardiology, Medical School, National & Kapodistrian University of Athens, Hippokration Hospital, Athens, Greece
| | - Yuqing Zhang
- Department of Cardiology, Fu Wai Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China
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Vink S, Akondi KB, Jin J, Poth K, Torres AM, Kuchel PW, Burke SL, Head GA, Alewood PF. Taipan Natriuretic Peptides Are Potent and Selective Agonists for the Natriuretic Peptide Receptor A. Molecules 2023; 28:molecules28073063. [PMID: 37049825 PMCID: PMC10095932 DOI: 10.3390/molecules28073063] [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: 02/20/2023] [Revised: 03/10/2023] [Accepted: 03/13/2023] [Indexed: 04/14/2023] Open
Abstract
Cardiovascular ailments are a major cause of mortality where over 1.3 billion people suffer from hypertension leading to heart-disease related deaths. Snake venoms possess a broad repertoire of natriuretic peptides with therapeutic potential for treating hypertension, congestive heart failure, and related cardiovascular disease. We now describe several taipan (Oxyuranus microlepidotus) natriuretic peptides TNPa-e which stimulated cGMP production through the natriuretic peptide receptor A (NPR-A) with higher potencies for the rat NPR-A (rNPR-A) over human NPR-A (hNPR-A). TNPc and TNPd were the most potent, demonstrating 100- and 560-fold selectivity for rNPR-A over hNPR-A. In vivo studies found that TNPc decreased diastolic and systolic blood pressure (BP) and increased heart rate (HR) in conscious normotensive rabbits, to a level that was similar to that of human atrial natriuretic peptide (hANP). TNPc also enhanced the bradycardia due to cardiac afferent stimulation (Bezold-Jarisch reflex). This indicated that TNPc possesses the ability to lower blood pressure and facilitate cardiac vagal afferent reflexes but unlike hANP does not produce tachycardia. The 3-dimensional structure of TNPc was well defined within the pharmacophoric disulfide ring, displaying two turn-like regions (RMSD = 1.15 Å). Further, its much greater biological stability together with its selectivity and potency will enhance its usefulness as a biological tool.
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Affiliation(s)
- Simone Vink
- Institute for Molecular Bioscience, The University of Queensland, St Lucia 4072, Australia
| | - Kalyana Bharati Akondi
- Department of Pathology and Immunology, Faculty of Medicine, University of Geneva, CH-1211 Geneva, Switzerland
| | - Jean Jin
- Institute for Molecular Bioscience, The University of Queensland, St Lucia 4072, Australia
| | - Kim Poth
- Institute for Molecular Bioscience, The University of Queensland, St Lucia 4072, Australia
| | - Allan M Torres
- Nanoscale Organisation and Dynamics Group, Western Sydney University, Penrith 2759, Australia
| | - Philip W Kuchel
- School of Life and Environmental Sciences, University of Sydney, Sydney 2006, Australia
| | - Sandra L Burke
- Baker Heart and Diabetes Institute, Melbourne 3004, Australia
| | - Geoffrey A Head
- Baker Heart and Diabetes Institute, Melbourne 3004, Australia
| | - Paul F Alewood
- Institute for Molecular Bioscience, The University of Queensland, St Lucia 4072, Australia
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7
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Pearson JT, Phillips JK, Head GA. Editorial: Insights in integrative physiology: 2021. Front Physiol 2023; 14:1186581. [PMID: 37064895 PMCID: PMC10092346 DOI: 10.3389/fphys.2023.1186581] [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] [Received: 03/15/2023] [Accepted: 03/20/2023] [Indexed: 03/29/2023] Open
Affiliation(s)
- James T. Pearson
- National Cerebral and Cardiovascular Center, Suita, Japan
- Department of Physiology, Monash Biomedicine Discovery Institute, Monash University, Clayton, VIC, Australia
| | - Jacqueline K. Phillips
- Macquarie Medical School, Macquarie University, Sydney, NSW, Australia
- *Correspondence: Jacqueline K. Phillips,
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Jama H, RhysJones D, Nakai M, Yao CKK, Climie RE, Sata Y, Anderson D, Creek DJ, Head GA, Kaye DM, Mackay C, Muir J, Marques FZ. S-57-3: GUT MICROBIAL METABOLITES LOWER 24-HOUR SYSTOLIC BLOOD PRESSURE IN HYPERTENSIVE PATIENTS. J Hypertens 2023. [DOI: 10.1097/01.hjh.0000914028.19216.37] [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] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
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Dinakis E, Nakai M, Gill P, Ribeiro R, Yiallourou S, Sata Y, Muir J, Carrington M, Head GA, Kaye DM, Marques FZ. Association Between the Gut Microbiome and Their Metabolites With Human Blood Pressure Variability. Hypertension 2022; 79:1690-1701. [PMID: 35674054 DOI: 10.1161/hypertensionaha.122.19350] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
BACKGROUND Blood pressure (BP) variability is an independent risk factor for cardiovascular events. Recent evidence supports a role for the gut microbiota in BP regulation. However, whether the gut microbiome is associated with BP variability is yet to be determined. Here, we aimed to investigate the interplay between the gut microbiome and their metabolites in relation to BP variability. METHODS Ambulatory BP monitoring was performed in 69 participants from Australia (55.1% women; mean±SD, 59.8±7.26 years; body mass index, 25.2±2.83 kg/m2). These data were used to determine nighttime dipping, morning BP surge (MBPS) and BP variability as SD. The gut microbiome was determined by 16S ribosomal RNA (rRNA) sequencing and metabolite levels by gas chromatography. RESULTS We identified specific taxa associated with systolic BP variability, nighttime dipping, and MBPS. Notably, Alistipesfinegoldii and Lactobacillus spp. were only present in participants within the normal ranges of BP variability, MBPS and dipping, while Prevotella spp. and Clostridium spp., were found to be present in extreme dippers and the highest quartiles of BP SD and MBPS. There was a negative association between MBPS and microbial α-diversity (r=-0.244, P=0.046). MBPS was also negatively associated with plasma levels of microbial metabolites called short-chain fatty acids (r=-0.305, P=0.020), particularly acetate (r=-0.311, P=0.017). CONCLUSIONS Gut microbiome diversity, levels of microbial metabolites, and the bacteria Alistipesfinegoldii and Lactobacillus were associated with lower BP variability and Clostridium and Prevotella with higher BP variability. Thus, our findings suggest the gut microbiome and metabolites may be involved in the regulation of BP variability.
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Affiliation(s)
- Evany Dinakis
- Hypertension Research Laboratory, School of Biological Sciences (E.D., M.N., F.Z.M), Monash University, Melbourne, Australia
| | - Michael Nakai
- Hypertension Research Laboratory, School of Biological Sciences (E.D., M.N., F.Z.M), Monash University, Melbourne, Australia
| | - Paul Gill
- Department of Gastroenterology (P.G., J.M.), Monash University, Melbourne, Australia
| | - Rosilene Ribeiro
- School of Life and Environmental Sciences, Charles Perkins Centre, University of Sydney, Australia (R.R.)
| | - Stephanie Yiallourou
- Central Clinical School, Faculty of Medicine Nursing and Health Sciences (Y.S., D.M.K.), Monash University, Melbourne, Australia.,Preclinical Disease and Prevention (S.Y., M.C.), Baker Heart and Diabetes Institute, Melbourne, Australia.,Department of Cardiology, Alfred Hospital, Melbourne, Australia (Y.S., D.M.K.)
| | - Yusuke Sata
- Neuropharmacology Laboratory (Y.S., G.A.H.), Baker Heart and Diabetes Institute, Melbourne, Australia
| | - Jane Muir
- Department of Gastroenterology (P.G., J.M.), Monash University, Melbourne, Australia
| | - Melinda Carrington
- Preclinical Disease and Prevention (S.Y., M.C.), Baker Heart and Diabetes Institute, Melbourne, Australia
| | - Geoffrey A Head
- Department of Pharmacology, Faculty of Medicine Nursing and Health Sciences (G.A.H.), Monash University, Melbourne, Australia.,Neuropharmacology Laboratory (Y.S., G.A.H.), Baker Heart and Diabetes Institute, Melbourne, Australia
| | - David M Kaye
- Central Clinical School, Faculty of Medicine Nursing and Health Sciences (Y.S., D.M.K.), Monash University, Melbourne, Australia.,Heart Failure Research Group (D.M.K., F.Z.M.), Baker Heart and Diabetes Institute, Melbourne, Australia.,Department of Cardiology, Alfred Hospital, Melbourne, Australia (Y.S., D.M.K.)
| | - Francine Z Marques
- Hypertension Research Laboratory, School of Biological Sciences (E.D., M.N., F.Z.M), Monash University, Melbourne, Australia.,Heart Failure Research Group (D.M.K., F.Z.M.), Baker Heart and Diabetes Institute, Melbourne, Australia
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10
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Paterson MR, Jackson KL, Dona MSI, Farrugia GE, Visniauskas B, Watson AMD, Johnson C, Prieto MC, Evans RG, Charchar F, Pinto AR, Marques FZ, Head GA. Deficiency of MicroRNA-181a Results in Transcriptome-Wide Cell-Specific Changes in the Kidney and Increases Blood Pressure. Hypertension 2021; 78:1322-1334. [PMID: 34538100 PMCID: PMC8573069 DOI: 10.1161/hypertensionaha.121.17384] [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] [Indexed: 11/16/2022]
Abstract
[Figure: see text].
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Affiliation(s)
- Madeleine R. Paterson
- Hypertension Research Laboratory, School of Biological Sciences, Faculty of Science, Monash University, Melbourne, Australia; Monash University, Melbourne, Australia
- Neuropharmacology Laboratory, Baker Heart and Diabetes Institute, Melbourne, Australia
| | - Kristy L. Jackson
- Neuropharmacology Laboratory, Baker Heart and Diabetes Institute, Melbourne, Australia
- Drug Discovery Biology, Faculty of Pharmacy and Pharmaceutical Sciences, Monash University Parkville, Australia
| | - Malathi S. I. Dona
- Cardiac Cellular Systems Laboratory, Baker Heart and Diabetes Institute, Melbourne, Australia
| | - Gabriella E. Farrugia
- Cardiac Cellular Systems Laboratory, Baker Heart and Diabetes Institute, Melbourne, Australia
| | - Bruna Visniauskas
- Department of Physiology, School of Medicine, Tulane University, New Orleans, the USA
| | - Anna M. D. Watson
- Neuropharmacology Laboratory, Baker Heart and Diabetes Institute, Melbourne, Australia
- Department of Diabetes, Central Clinical School, Monash University, Melbourne, Australia
| | - Chad Johnson
- Monash Micro Imaging, Monash University, Melbourne, Australia
| | - Minolfa C. Prieto
- Department of Physiology, School of Medicine, Tulane University, New Orleans, the USA
| | - Roger G. Evans
- Cardiovascular Disease Program, Biomedicine Discovery Institute and Department of Physiology, Monash University, Melbourne, Australia
| | - Fadi Charchar
- Health Innovation and Transformation Centre, Federation University, Ballarat, Australia
- Department of Physiology, University of Melbourne, Melbourne, Australia
| | - Alexander R. Pinto
- Drug Discovery Biology, Faculty of Pharmacy and Pharmaceutical Sciences, Monash University Parkville, Australia
- Centre for Cardiovascular Biology and Disease Research, La Trobe University, Melbourne, Australia
| | - Francine Z. Marques
- Hypertension Research Laboratory, School of Biological Sciences, Faculty of Science, Monash University, Melbourne, Australia; Monash University, Melbourne, Australia
- Heart Failure Research Group, Baker Heart and Diabetes Institute, Melbourne, Australia
| | - Geoffrey A. Head
- Neuropharmacology Laboratory, Baker Heart and Diabetes Institute, Melbourne, Australia
- Department of Pharmacology, Monash University, Melbourne, Australia
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11
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Sata Y, Burke SL, Eikelis N, Watson AMD, Gueguen C, Jackson KL, Lambert GW, Lim K, Denton KM, Schlaich MP, Head GA. Renal Deafferentation Prevents Progression of Hypertension and Changes to Sympathetic Reflexes in a Rabbit Model of Chronic Kidney Disease. Hypertension 2021; 78:1310-1321. [PMID: 34538104 DOI: 10.1161/hypertensionaha.121.17037] [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] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
[Figure: see text].
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Affiliation(s)
- Yusuke Sata
- Neuropharmacology Laboratory (Y.S., S.L.B., A.M.D.W., C.G., K.L.J., K.L., G.A.H.), Baker Heart and Diabetes Institute, Melbourne, VIC, Australia.,Human Neurotransmitters Laboratory (Y.S., M.P.S., G.W.L., N.E.), Baker Heart and Diabetes Institute, Melbourne, VIC, Australia.,Faculty of Medicine, Nursing and Health Sciences, Central Clinical School (Y.S.), Monash University, Melbourne, VIC, Australia.,Department of Cardiology, Alfred Hospital, Melbourne, VIC, Australia (Y.S.)
| | - Sandra L Burke
- Neuropharmacology Laboratory (Y.S., S.L.B., A.M.D.W., C.G., K.L.J., K.L., G.A.H.), Baker Heart and Diabetes Institute, Melbourne, VIC, Australia
| | - Nina Eikelis
- Human Neurotransmitters Laboratory (Y.S., M.P.S., G.W.L., N.E.), Baker Heart and Diabetes Institute, Melbourne, VIC, Australia.,Iverson Health Innovation Research Institute and School of Health Sciences, Swinburne University of Technology, Hawthorn, VIC, Australia (N.E., G.W.L.)
| | - Anna M D Watson
- Neuropharmacology Laboratory (Y.S., S.L.B., A.M.D.W., C.G., K.L.J., K.L., G.A.H.), Baker Heart and Diabetes Institute, Melbourne, VIC, Australia.,Department of Diabetes, Central Clinical School (A.M.D.W.), Monash University, Melbourne, VIC, Australia
| | - Cindy Gueguen
- Neuropharmacology Laboratory (Y.S., S.L.B., A.M.D.W., C.G., K.L.J., K.L., G.A.H.), Baker Heart and Diabetes Institute, Melbourne, VIC, Australia
| | - Kristy L Jackson
- Neuropharmacology Laboratory (Y.S., S.L.B., A.M.D.W., C.G., K.L.J., K.L., G.A.H.), Baker Heart and Diabetes Institute, Melbourne, VIC, Australia.,Drug Discovery Biology, Monash Institute of Pharmaceutical Sciences (K.L.J), Monash University, Melbourne, VIC, Australia
| | - Gavin W Lambert
- Human Neurotransmitters Laboratory (Y.S., M.P.S., G.W.L., N.E.), Baker Heart and Diabetes Institute, Melbourne, VIC, Australia.,Iverson Health Innovation Research Institute and School of Health Sciences, Swinburne University of Technology, Hawthorn, VIC, Australia (N.E., G.W.L.)
| | - Kyungjoon Lim
- Neuropharmacology Laboratory (Y.S., S.L.B., A.M.D.W., C.G., K.L.J., K.L., G.A.H.), Baker Heart and Diabetes Institute, Melbourne, VIC, Australia.,Department of Physiology, Anatomy and Microbiology, La Trobe University, Melbourne, VIC, Australia (K.L.)
| | - Kate M Denton
- Cardiovascular Program, Monash Biomedicine Discovery Institute and Department of Physiology, Monash University, Clayton, VIC, Australia (K.M.D.)
| | - Markus P Schlaich
- Human Neurotransmitters Laboratory (Y.S., M.P.S., G.W.L., N.E.), Baker Heart and Diabetes Institute, Melbourne, VIC, Australia.,Departments of Cardiology and Nephrology, Dobney Hypertension Centre, School of Medicine, Royal Perth Hospital Unit, University of Western Australia, Royal Perth Hospital (M.P.S.)
| | - Geoffrey A Head
- Neuropharmacology Laboratory (Y.S., S.L.B., A.M.D.W., C.G., K.L.J., K.L., G.A.H.), Baker Heart and Diabetes Institute, Melbourne, VIC, Australia.,Department of Pharmacology (G.A.H.), Monash University, Melbourne, VIC, Australia
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12
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Dinakis E, Nakai M, Gill PA, Yiallourou S, Sata Y, Muir J, Carrington M, Head GA, Kaye DM, Marques FZ. The Gut Microbiota and Their Metabolites in Human Arterial Stiffness. Heart Lung Circ 2021; 30:1716-1725. [PMID: 34452845 DOI: 10.1016/j.hlc.2021.07.022] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [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: 07/11/2021] [Revised: 07/21/2021] [Accepted: 07/26/2021] [Indexed: 01/13/2023]
Abstract
AIM Gut microbiota-derived metabolites, such as short-chain fatty acids (SCFAs) have vasodilator properties in animal and human ex vivo arteries. However, the role of the gut microbiota and SCFAs in arterial stiffness in humans is still unclear. Here we aimed to determine associations between the gut microbiome, SCFA and their G-protein coupled sensing receptors (GPCRs) in relation to human arterial stiffness. METHODS Ambulatory arterial stiffness index (AASI) was determined from ambulatory blood pressure (BP) monitoring in 69 participants from regional and metropolitan regions in Australia (55.1% women; mean, 59.8± SD, 7.26 years of age). The gut microbiome was determined by 16S rRNA sequencing, SCFA levels by gas chromatography, and GPCR expression in circulating immune cells by real-time PCR. RESULTS There was no association between metrics of bacterial α and β diversity and AASI or AASI quartiles in men and women. We identified two main bacteria taxa that were associated with AASI quartiles: Lactobacillus spp. was only present in the lowest quartile, while Clostridium spp. was present in all quartiles but the lowest. AASI was positively associated with higher levels of plasma, but not faecal, butyrate. Finally, we identified that the expression of GPR43 (FFAR2) and GPR41 (FFAR3) in circulating immune cells were negatively associated with AASI. CONCLUSIONS Our results suggest that arterial stiffness is associated with lower levels of the metabolite-sensing receptors GPR41/GPR43 in humans, blunting its response to BP-lowering metabolites such as butyrate. The role of Lactobacillus spp. and Clostridium spp., as well as butyrate-sensing receptors GPR41/GPR43, in human arterial stiffness needs to be determined.
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Affiliation(s)
- Evany Dinakis
- Hypertension Research Laboratory, School of Biological Sciences, Monash University, Melbourne, Vic, Australia
| | - Michael Nakai
- Hypertension Research Laboratory, School of Biological Sciences, Monash University, Melbourne, Vic, Australia
| | - Paul A Gill
- Department of Gastroenterology, Monash University, Melbourne, Vic, Australia
| | - Stephanie Yiallourou
- Preclinical Disease and Prevention, Baker Heart and Diabetes Institute, Melbourne, Vic, Australia
| | - Yusuke Sata
- Neuropharmacology Laboratory, Baker Heart and Diabetes Institute, Melbourne, Vic, Australia; Central Clinical School, Faculty of Medicine Nursing and Health Sciences, Monash University, Melbourne, Vic, Australia; Department of Cardiology, Alfred Hospital, Melbourne, Vic, Australia
| | - Jane Muir
- Department of Gastroenterology, Monash University, Melbourne, Vic, Australia
| | - Melinda Carrington
- Preclinical Disease and Prevention, Baker Heart and Diabetes Institute, Melbourne, Vic, Australia
| | - Geoffrey A Head
- Neuropharmacology Laboratory, Baker Heart and Diabetes Institute, Melbourne, Vic, Australia; Department of Pharmacology, Faculty of Medicine Nursing and Health Sciences, Monash University, Melbourne, Vic, Australia
| | - David M Kaye
- Central Clinical School, Faculty of Medicine Nursing and Health Sciences, Monash University, Melbourne, Vic, Australia; Department of Cardiology, Alfred Hospital, Melbourne, Vic, Australia; Heart Failure Research Group, Baker Heart and Diabetes Institute, Melbourne, Vic, Australia
| | - Francine Z Marques
- Hypertension Research Laboratory, School of Biological Sciences, Monash University, Melbourne, Vic, Australia; Heart Failure Research Group, Baker Heart and Diabetes Institute, Melbourne, Vic, Australia.
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13
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Eikelis N, Dixon JB, Lambert EA, Hanin G, Tzur Y, Greenberg DS, Soreq H, Marques FZ, Fahey MT, Head GA, Schlaich MP, Lambert GW. MicroRNA-132 may be associated with blood pressure and liver steatosis-preliminary observations in obese individuals. J Hum Hypertens 2021; 36:911-916. [PMID: 34453104 DOI: 10.1038/s41371-021-00597-2] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2021] [Revised: 08/08/2021] [Accepted: 08/18/2021] [Indexed: 11/09/2022]
Abstract
Recent findings in experimental models have shown that the microRNA miR-132 (mir-132) is an important regulator of liver homeostasis and lipid metabolism. We aimed to assess miR-132 expression in liver and fat tissues of obese individuals and examine its association with blood pressure (BP) and hepatic steatosis. We examined obese individuals undergoing bariatric surgery for weight loss (n = 19). Clinical and demographic information was obtained. Quantitative PCR was performed to determine tissue expression of miR-132 in liver and subcutaneous and visceral fat biopsies obtained during bariatric surgery. Liver biopsies were read by a single liver pathologist and graded for steatosis, inflammation and fibrosis. Participants (aged 39 ± 8.1 years) had a body mass index (BMI) of 42 ± 4.5 kg/m2 and presented with 2.2 ± 1.2 metabolic abnormalities. Supine BP was 127 ± 16/74 ± 11 mmHg. Hepatic and visceral fat expression of miR-132 were correlated (r = 0.59, P = 0.033). There was no correlation between subcutaneous and visceral expression of miR-132 (r = -0.31, P = 0.20). Hepatic and visceral fat miR-132 expression were associated with BMI (r = 0.62 and r = 0.68, P = 0.049 respectively) and degree of liver steatosis (r = 0.60 and r = 0.55, P < 0.05, respectively). Subcutaneous fat miRNA-132 expression was correlated to office systolic BP (r = 0.46, P < 0.05), several aspects of 24 h BP (24 h systolic BP: r = 0.52; day systolic BP: r = 0.59, P < 0.05 for all), plasma triglycerides (r = 0.51, P < 0.01) and liver enzymes (ALT: r = -0.52; AST: r = -0.48, P < 0.05 for all). We found an association between miR-132 and markers of cardiovascular and metabolic disease. Reduction of miR-132 may be a target for the regulation of liver lipid homeostasis and control of obesity-related blood pressure.
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Affiliation(s)
- Nina Eikelis
- Iverson Health Innovation Research Institute and School of Health Sciences, Swinburne University of Technology, Melbourne, VIC, Australia.,Baker Heart & Diabetes Institute, Melbourne, VIC, Australia
| | - John B Dixon
- Iverson Health Innovation Research Institute and School of Health Sciences, Swinburne University of Technology, Melbourne, VIC, Australia.,Baker Heart & Diabetes Institute, Melbourne, VIC, Australia
| | - Elisabeth A Lambert
- Iverson Health Innovation Research Institute and School of Health Sciences, Swinburne University of Technology, Melbourne, VIC, Australia.,Baker Heart & Diabetes Institute, Melbourne, VIC, Australia
| | - Geula Hanin
- Department of Genetics, University of Cambridge, Cambridge, UK.,The Institute of Life Sciences, The Hebrew University of Jerusalem, Jerusalem, Israel
| | - Yonat Tzur
- The Institute of Life Sciences, The Hebrew University of Jerusalem, Jerusalem, Israel
| | - David S Greenberg
- The Institute of Life Sciences, The Hebrew University of Jerusalem, Jerusalem, Israel
| | - Hermona Soreq
- The Institute of Life Sciences, The Hebrew University of Jerusalem, Jerusalem, Israel
| | - Francine Z Marques
- Hypertension Research Laboratory, School of Biological Sciences, Faculty of Science, Monash University, Melbourne, VIC, Australia
| | - Michael T Fahey
- Iverson Health Innovation Research Institute and School of Health Sciences, Swinburne University of Technology, Melbourne, VIC, Australia
| | - Geoffrey A Head
- Baker Heart & Diabetes Institute, Melbourne, VIC, Australia.,Department of Pharmacology, Monash University, Melbourne, VIC, Australia
| | - Markus P Schlaich
- Baker Heart & Diabetes Institute, Melbourne, VIC, Australia.,Dobney Hypertension Centre, School of Medicine-Royal Perth Hospital Unit, University of Western Australia, Perth, WA, Australia
| | - Gavin W Lambert
- Iverson Health Innovation Research Institute and School of Health Sciences, Swinburne University of Technology, Melbourne, VIC, Australia. .,Baker Heart & Diabetes Institute, Melbourne, VIC, Australia.
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14
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Jama HA, Muralitharan RR, Xu C, O'Donnell JA, Bertagnolli M, Broughton BRS, Head GA, Marques FZ. Rodent models of hypertension. Br J Pharmacol 2021; 179:918-937. [PMID: 34363610 DOI: 10.1111/bph.15650] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [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: 12/17/2020] [Revised: 03/02/2021] [Accepted: 03/03/2021] [Indexed: 01/03/2023] Open
Abstract
Elevated blood pressure (BP), or hypertension, is the main risk factor for cardiovascular disease. As a multifactorial and systemic disease that involves multiple organs and systems, hypertension remains a challenging disease to study. Models of hypertension are invaluable to support the discovery of the specific genetic, cellular and molecular mechanisms underlying essential hypertension, as well as to test new possible treatments to lower BP. Rodent models have proven to be an invaluable tool for advancing the field. In this review, we discuss the strengths and weaknesses of rodent models of hypertension through a systems approach. We highlight the ways how target organs and systems including the kidneys, vasculature, the sympathetic nervous system (SNS), immune system and the gut microbiota influence BP in each rodent model. We also discuss often overlooked hypertensive conditions such as pulmonary hypertension and hypertensive-pregnancy disorders, providing an important resource for researchers.
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Affiliation(s)
- Hamdi A Jama
- Hypertension Research Laboratory, School of Biological Sciences, Faculty of Science, Monash University, Melbourne, Australia.,Heart Failure Research Laboratory, Baker Heart and Diabetes Institute, Melbourne, Australia
| | - Rikeish R Muralitharan
- Hypertension Research Laboratory, School of Biological Sciences, Faculty of Science, Monash University, Melbourne, Australia.,Institute for Medical Research, Ministry of Health Malaysia, Kuala Lumpur, Malaysia
| | - Chudan Xu
- Hypertension Research Laboratory, School of Biological Sciences, Faculty of Science, Monash University, Melbourne, Australia
| | - Joanne A O'Donnell
- Hypertension Research Laboratory, School of Biological Sciences, Faculty of Science, Monash University, Melbourne, Australia
| | - Mariane Bertagnolli
- Laboratory of Maternal-child Health, Hospital Sacre-Coeur Research Center, CIUSSS Nord-de-l'Île-de-Montréal, Montreal, Canada.,School of Physical and Occupational Therapy, Faculty of Medicine, McGill University, Montreal, Canada
| | - Bradley R S Broughton
- Department of Pharmacology, Biomedicine Discovery Institute, Faculty of Medicine Nursing and Health Sciences, Monash University, Melbourne, Australia
| | - Geoffrey A Head
- Department of Pharmacology, Biomedicine Discovery Institute, Faculty of Medicine Nursing and Health Sciences, Monash University, Melbourne, Australia.,Neuropharmacology Laboratory, Baker Heart and Diabetes Institute, Melbourne, Australia
| | - Francine Z Marques
- Hypertension Research Laboratory, School of Biological Sciences, Faculty of Science, Monash University, Melbourne, Australia.,Heart Failure Research Laboratory, Baker Heart and Diabetes Institute, Melbourne, Australia
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15
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Nakai M, Ribeiro RV, Stevens BR, Gill P, Muralitharan RR, Yiallourou S, Muir J, Carrington M, Head GA, Kaye DM, Marques FZ. Essential Hypertension Is Associated With Changes in Gut Microbial Metabolic Pathways: A Multisite Analysis of Ambulatory Blood Pressure. Hypertension 2021; 78:804-815. [PMID: 34333988 DOI: 10.1161/hypertensionaha.121.17288] [Citation(s) in RCA: 30] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
[Figure: see text].
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Affiliation(s)
- Michael Nakai
- Hypertension Research Laboratory, School of Biological Sciences, Monash University, Melbourne, Australia (M.N., R.R.M., F.Z.M.)
| | - Rosilene V Ribeiro
- Charles Perkins Centre, University of Sydney, Australia (R.V.R.).,School of Life and Environmental Sciences, Faculty of Science, The University of Sydney, Australia (R.V.R.)
| | - Bruce R Stevens
- Department of Physiology and Functional Genomics, University of Florida, College of Medicine, Gainesville (B.R.S.)
| | - Paul Gill
- Department of Gastroenterology (P.G., J.M.), Monash University, Melbourne, Australia
| | - Rikeish R Muralitharan
- Hypertension Research Laboratory, School of Biological Sciences, Monash University, Melbourne, Australia (M.N., R.R.M., F.Z.M.).,Institute for Medical Research, Ministry of Health Malaysia, Kuala Lumpur (R.R.M.)
| | - Stephanie Yiallourou
- Preclinical Disease and Prevention, Baker Heart and Diabetes Institute, Melbourne, Australia (S.Y., M.C.)
| | - Jane Muir
- Department of Gastroenterology (P.G., J.M.), Monash University, Melbourne, Australia
| | - Melinda Carrington
- Preclinical Disease and Prevention, Baker Heart and Diabetes Institute, Melbourne, Australia (S.Y., M.C.)
| | - Geoffrey A Head
- Department of Pharmacology, Faculty of Medicine Nursing and Health Sciences (G.A.H.), Monash University, Melbourne, Australia.,Neuropharmacology Laboratory, Baker Heart and Diabetes Institute, Melbourne, Australia (G.A.H.)
| | - David M Kaye
- Clinical School, Faculty of Medicine Nursing and Health Sciences (D.M.K.), Monash University, Melbourne, Australia.,Heart Failure Research Group, Baker Heart and Diabetes Institute, Melbourne, Australia (D.M.K., F.Z.M.).,Department of Cardiology, Alfred Hospital, Melbourne, Australia (D.M.K.)
| | - Francine Z Marques
- Hypertension Research Laboratory, School of Biological Sciences, Monash University, Melbourne, Australia (M.N., R.R.M., F.Z.M.).,Heart Failure Research Group, Baker Heart and Diabetes Institute, Melbourne, Australia (D.M.K., F.Z.M.)
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16
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Rhys-Jones D, Climie RE, Gill PA, Jama HA, Head GA, Gibson PR, Kaye DM, Muir JG, Marques FZ. Microbial Interventions to Control and Reduce Blood Pressure in Australia (MICRoBIA): rationale and design of a double-blinded randomised cross-over placebo controlled trial. Trials 2021; 22:496. [PMID: 34315522 PMCID: PMC8313879 DOI: 10.1186/s13063-021-05468-2] [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] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2021] [Accepted: 07/17/2021] [Indexed: 12/01/2022] Open
Abstract
Background Hypertension is a prevalent chronic disease worldwide that remains poorly controlled. Recent studies support the concept that the gut microbiota is involved in the development of hypertension and that dietary fibre intake may act through the gut microbiota to lower blood pressure (BP). Resistant starch is a type of prebiotic fibre which is metabolised by commensal bacteria in the colon to produce short-chain fatty acids (SCFAs), including acetate, propionate, and butyrate. Previous work in pre-clinical models provides strong evidence that both prebiotic fibre as well as SCFAs (i.e. postbiotics) can prevent the development of hypertension. The aim of this clinical trial is to determine if acetylated and butyrylated modified resistant starch can decrease BP of hypertensive individuals via the modulation of the gut microbiota and release of high levels of SCFAs. Methods This is a phase IIa double-blinded, randomised, cross-over, placebo controlled trial. Participants are randomly allocated to receive either a diet containing 40 g/day of the modified resistant starch or placebo (corn starch or regular flour) for 3 weeks on each diet, with a 3-week washout period between the two diets. BP is measured in the office, at home, and using a 24-h ambulatory device. Arterial stiffness is measured using carotid-to-femoral pulse wave velocity. Our primary endpoint is a reduction in ambulatory daytime systolic BP. Secondary endpoints include changes to circulating cytokines, immune markers, and modulation to the gut microbiome. Discussion The findings of this study will provide the first evidence for the use of a combination of pre- and postbiotics to lower BP in humans. The results are expected at the end of 2021. Trial registration Australia and New Zealand Clinical Trial Registry ACTRN12619000916145. Registered on 1 July 2019.
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Affiliation(s)
- Dakota Rhys-Jones
- Hypertension Research Laboratory, School of Biological Sciences, Faculty of Science, Monash University, 25 Rainforest Walk, Clayton, Victoria, 3800, Australia.,Department of Gastroenterology, Central Clinical School, Monash University, Melbourne, Australia
| | - Rachel E Climie
- Sports Cardiology, Baker Heart and Diabetes Institute, Melbourne, Australia.,Menzies Institute for Medical Research, University of Tasmanian, Hobart, Australia
| | - Paul A Gill
- Department of Gastroenterology, Central Clinical School, Monash University, Melbourne, Australia
| | - Hamdi A Jama
- Hypertension Research Laboratory, School of Biological Sciences, Faculty of Science, Monash University, 25 Rainforest Walk, Clayton, Victoria, 3800, Australia
| | - Geoffrey A Head
- Neuropharmacology Laboratory, Baker Heart and Diabetes Institute, Melbourne, Australia.,Department of Pharmacology, Monash University, Melbourne, Australia
| | - Peter R Gibson
- Department of Gastroenterology, Central Clinical School, Monash University, Melbourne, Australia
| | - David M Kaye
- Heart Failure Research Group, Baker Heart and Diabetes Institute, Melbourne, Australia.,Central Clinical School, Faculty of Medicine Nursing and Health Sciences, Monash University, Melbourne, Australia.,Department of Cardiology, Alfred Hospital, Melbourne, Australia
| | - Jane G Muir
- Department of Gastroenterology, Central Clinical School, Monash University, Melbourne, Australia
| | - Francine Z Marques
- Hypertension Research Laboratory, School of Biological Sciences, Faculty of Science, Monash University, 25 Rainforest Walk, Clayton, Victoria, 3800, Australia. .,Heart Failure Research Group, Baker Heart and Diabetes Institute, Melbourne, Australia.
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17
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Lim K, Burke SL, Marques FZ, Jackson KL, Gueguen C, Sata Y, Armitage JA, Head GA. Leptin and Melanocortin Signaling Mediates Hypertension in Offspring From Female Rabbits Fed a High-Fat Diet During Gestation and Lactation. Front Physiol 2021; 12:693157. [PMID: 34248679 PMCID: PMC8264761 DOI: 10.3389/fphys.2021.693157] [Citation(s) in RCA: 7] [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] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2021] [Accepted: 05/24/2021] [Indexed: 01/02/2023] Open
Abstract
Maternal high-fat diet in rabbits leads to hypertension and elevated renal sympathetic nerve activity (RSNA) in adult offspring but whether this is due to adiposity or maternal programming is unclear. We gave intracerebroventricular (ICV) and ventromedial hypothalamus (VMH) administration of leptin-receptor antagonist, α-melanocyte-stimulating hormone (αMSH), melanocortin-receptor antagonist (SHU9119), or insulin-receptor (InsR) antagonist to conscious adult offspring from mothers fed a high-fat diet (mHFD), control diet (mCD), or mCD offspring fed HFD for 10d (mCD10d, to deposit equivalent fat but not during development). mHFD and mCD10d rabbits had higher mean arterial pressure (MAP, +6.4 mmHg, +12.1 mmHg, p < 0.001) and RSNA (+2.3 nu, +3.2 nu, p < 0.01) than mCD, but all had similar plasma leptin. VMH leptin-receptor antagonist reduced MAP (−8.0 ± 3.0 mmHg, p < 0.001) in mCD10d but not in mHFD or mCD group. Intracerebroventricular leptin-receptor antagonist reduced MAP only in mHFD rabbits (p < 0.05). Intracerebroventricular SHU9119 reduced MAP and RSNA in mHFD but only reduced MAP in the mCD10d group. VMH αMSH increased RSNA (+85%, p < 0.001) in mHFD rabbits but ICV αMSH increased RSNA in both mHFD and mCD10d rabbits (+45%, +51%, respectively, p < 0.001). The InsR antagonist had no effect by either route on MAP or RSNA. Hypothalamic leptin receptor and brain-derived neurotrophic factor (BDNF) mRNA were greater in mHFD compared with mCD rabbits and mCD10d rabbits. In conclusion, the higher MAP in mHFD and mCD10d offspring was likely due to greater central leptin signaling at distinct sites within the hypothalamus while enhanced melanocortin contribution was common to both groups suggesting that residual body fat was mainly responsible. However, the effects of SHU9119 and αMSH on RSNA pathways only in mHFD suggest a maternal HFD may program sympatho-excitatory capacity in these offspring and that this may involve increased leptin receptor and BDNF expression.
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Affiliation(s)
- Kyungjoon Lim
- Neuropharmacology Laboratory, Baker Heart and Diabetes Institute, Melbourne, VIC, Australia.,Department of Physiology, Anatomy and Microbiology, La Trobe University, Bundoora, VIC, Australia
| | - Sandra L Burke
- Neuropharmacology Laboratory, Baker Heart and Diabetes Institute, Melbourne, VIC, Australia
| | - Francine Z Marques
- Heart Failure Research Group, Baker Heart and Diabetes Institute, Melbourne, VIC, Australia.,Hypertension Research Laboratory, School of Biological Sciences, Faculty of Science, Monash University, Clayton, VIC, Australia
| | - Kristy L Jackson
- Neuropharmacology Laboratory, Baker Heart and Diabetes Institute, Melbourne, VIC, Australia
| | - Cindy Gueguen
- Neuropharmacology Laboratory, Baker Heart and Diabetes Institute, Melbourne, VIC, Australia
| | - Yusuke Sata
- Neuropharmacology Laboratory, Baker Heart and Diabetes Institute, Melbourne, VIC, Australia.,Human Neurotransmitters Laboratory, Baker Heart and Diabetes Institute, Melbourne, VIC, Australia.,Faculty of Medicine, Nursing and Health Sciences, Central Clinical School, Monash University, Melbourne, VIC, Australia.,Department of Cardiology, Alfred Hospital, Melbourne, VIC, Australia
| | - James A Armitage
- School of Medicine (Optometry), and IMPACT Institute for Innovation in Physical and Mental Health and Clinical Translation, Faculty of Health, Deakin University, Waurn Ponds, VIC, Australia
| | - Geoffrey A Head
- Neuropharmacology Laboratory, Baker Heart and Diabetes Institute, Melbourne, VIC, Australia.,Department of Pharmacology, Monash University, Clayton, VIC, Australia
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18
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Dragoljevic D, Veiga CB, Michell DL, Shihata WA, Al-Sharea A, Head GA, Murphy AJ, Kraakman MJ, Lee MKS. A spontaneously hypertensive diet-induced atherosclerosis-prone mouse model of metabolic syndrome. Biomed Pharmacother 2021; 139:111668. [PMID: 34243630 DOI: 10.1016/j.biopha.2021.111668] [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] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2021] [Revised: 04/20/2021] [Accepted: 04/23/2021] [Indexed: 02/07/2023] Open
Abstract
Metabolic Syndrome (MetS) is a complex and multifactorial condition often characterised by obesity, hypertension, hyperlipidaemia, insulin resistance, glucose intolerance and fasting hyperglycaemia. Collectively, MetS can increase the risk of atherosclerotic-cardiovascular disease, which is the leading cause of death worldwide. However, no animal model currently exists to study MetS in the context of atherosclerosis. In this study we developed a pre-clinical mouse model that recapitulates the spectrum of MetS features while developing atherosclerosis. When BPHx mice were placed on a western type diet for 16 weeks, all the classical characteristics of MetS were observed. Comprehensive metabolic analyses and atherosclerotic imaging revealed BPHx mice to be obese and hypertensive, with elevated total plasma cholesterol and triglyceride levels, that accelerated atherosclerosis. Altogether, we demonstrate that the BPHx mouse has all the major components of MetS, and accelerates the development of atherosclerosis.
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Affiliation(s)
- Dragana Dragoljevic
- Baker Heart and Diabetes Institute, Melbourne, VIC, Australia; The University of Melbourne, Melbourne, VIC, Australia; Monash University, Melbourne, VIC, Australia
| | - Camilla Bertuzzo Veiga
- Baker Heart and Diabetes Institute, Melbourne, VIC, Australia; The University of Melbourne, Melbourne, VIC, Australia
| | | | - Waled A Shihata
- Baker Heart and Diabetes Institute, Melbourne, VIC, Australia
| | - Annas Al-Sharea
- Baker Heart and Diabetes Institute, Melbourne, VIC, Australia
| | - Geoffrey A Head
- Baker Heart and Diabetes Institute, Melbourne, VIC, Australia
| | - Andrew J Murphy
- Baker Heart and Diabetes Institute, Melbourne, VIC, Australia; The University of Melbourne, Melbourne, VIC, Australia; Monash University, Melbourne, VIC, Australia
| | | | - Man K S Lee
- Baker Heart and Diabetes Institute, Melbourne, VIC, Australia; The University of Melbourne, Melbourne, VIC, Australia; Monash University, Melbourne, VIC, Australia.
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19
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Burke SL, Barzel B, Jackson KL, Gueguen C, Young MJ, Head GA. Role of Mineralocorticoid and Angiotensin Type 1 Receptors in the Paraventricular Nucleus in Angiotensin-Induced Hypertension. Front Physiol 2021; 12:640373. [PMID: 33762970 PMCID: PMC7982587 DOI: 10.3389/fphys.2021.640373] [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] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2020] [Accepted: 02/16/2021] [Indexed: 11/25/2022] Open
Abstract
The hypothalamic paraventricular nucleus (PVN) is an important site where an interaction between circulating angiotensin (Ang) and mineralocorticoid receptor (MR) activity may modify sympathetic nerve activity (SNA) to influence long-term elevation of blood pressure. We examined in conscious Ang II-treated rabbits, the effects on blood pressure and tonic and reflex renal SNA (RSNA) of microinjecting into the PVN either RU28318 to block MR, losartan to block Ang (AT1) receptors or muscimol to inhibit GABAA receptor agonist actions. Male rabbits received a moderate dose of Ang II (24 ng/kg/min subcutaneously) for 3 months (n = 13) or sham treatment (n = 13). At 3 months, blood pressure increased by +19% in the Ang II group compared to 10% in the sham (P = 0.022) but RSNA was similar. RU28318 lowered blood pressure in both Ang II and shams but had a greater effect on RSNA and heart rate in the Ang II-treated group (P < 0.05). Losartan also lowered RSNA, while muscimol produced sympatho-excitation in both groups. In Ang II-treated rabbits, RU28318 attenuated the blood pressure increase following chemoreceptor stimulation but did not affect responses to air jet stress. In contrast losartan and muscimol reduced blood pressure and RSNA responses to both hypoxia and air jet. While neither RU28318 nor losartan changed the RSNA baroreflex, RU28318 augmented the range of the heart rate baroreflex by 10% in Ang II-treated rabbits. Muscimol, however, augmented the RSNA baroreflex by 11% in sham animals and none of the treatments altered baroreflex sensitivity. In conclusion, 3 months of moderate Ang II treatment promotes activation of reflex RSNA principally via MR activation in the PVN, rather than via activation of AT1 receptors. However, the onset of hypertension is independent of both. Interestingly, the sympatho-excitatory effects of muscimol in both groups suggest that overall, the PVN regulates a tonic sympatho-inhibitory influence on blood pressure control.
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Affiliation(s)
- Sandra L Burke
- Neuropharmacology Laboratory, Baker Heart and Diabetes Institute, Melbourne, VIC, Australia
| | - Benjamin Barzel
- Neuropharmacology Laboratory, Baker Heart and Diabetes Institute, Melbourne, VIC, Australia
| | - Kristy L Jackson
- Neuropharmacology Laboratory, Baker Heart and Diabetes Institute, Melbourne, VIC, Australia
| | - Cindy Gueguen
- Neuropharmacology Laboratory, Baker Heart and Diabetes Institute, Melbourne, VIC, Australia
| | - Morag J Young
- Cardiovascular Endocrinology Laboratory, Baker Heart and Diabetes Institute, Melbourne, VIC, Australia
| | - Geoffrey A Head
- Neuropharmacology Laboratory, Baker Heart and Diabetes Institute, Melbourne, VIC, Australia.,Department of Pharmacology, Monash University, Clayton, VIC, Australia
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20
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Mouat MA, Jackson KL, Coleman JLJ, Paterson MR, Graham RM, Head GA, Smith NJ. Deletion of Orphan G Protein-Coupled Receptor GPR37L1 in Mice Alters Cardiovascular Homeostasis in a Sex-Specific Manner. Front Pharmacol 2021; 11:600266. [PMID: 33633567 PMCID: PMC7901490 DOI: 10.3389/fphar.2020.600266] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [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: 08/29/2020] [Accepted: 12/16/2020] [Indexed: 11/13/2022] Open
Abstract
GPR37L1 is a family A orphan G protein-coupled receptor (GPCR) with a putative role in blood pressure regulation and cardioprotection. In mice, genetic ablation of Gpr37l1 causes sex-dependent effects; female mice lacking Gpr37l1 (GPR37L1-/-) have a modest but significant elevation in blood pressure, while male GPR37L1-/- mice are more susceptible to cardiovascular dysfunction following angiotensin II-induced hypertension. Given that this receptor is highly expressed in the brain, we hypothesize that the cardiovascular phenotype of GPR37L1-/- mice is due to changes in autonomic regulation of blood pressure and heart rate. To investigate this, radiotelemetry was employed to characterize baseline cardiovascular variables in GPR37L1-/- mice of both sexes compared to wildtype controls, followed by power spectral analysis to quantify short-term fluctuations in blood pressure and heart rate attributable to alterations in autonomic homeostatic mechanisms. Additionally, pharmacological ganglionic blockade was performed to determine vasomotor tone, and environmental stress tests were used to assess whether cardiovascular reactivity was altered in GPR37L1-/- mice. We observed that mean arterial pressure was significantly lower in female GPR37L1-/- mice compared to wildtype counterparts, but was unchanged in male GPR37L1-/- mice. GPR37L1-/- genotype had a statistically significant positive chronotropic effect on heart rate across both sexes when analyzed by two-way ANOVA. Power spectral analysis of these data revealed a reduction in power in the heart rate spectrum between 0.5 and 3 Hz in female GPR37L1-/- mice during the diurnal active period, which indicates that GPR37L1-/- mice may have impaired cardiac vagal drive. GPR37L1-/- mice of both sexes also exhibited attenuated depressor responses to ganglionic blockade with pentolinium, indicating that GPR37L1 is involved in maintaining sympathetic vasomotor tone. Interestingly, when these mice were subjected to aversive and appetitive behavioral stressors, the female GPR37L1-/- mice exhibited an attenuation of cardiovascular reactivity to aversive, but not appetitive, environmental stimuli. Together, these results suggest that loss of GPR37L1 affects autonomic maintenance of blood pressure, giving rise to sex-specific cardiovascular changes in GPR37L1-/- mice.
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Affiliation(s)
- Margaret A Mouat
- Molecular Pharmacology Laboratory, Victor Chang Cardiac Research Institute, Sydney, NSW, Australia.,St Vincent's Clinical School, UNSW Sydney, Sydney, NSW, Australia.,Molecular Cardiology and Biophysics Division, Victor Chang Cardiac Research Institute, Sydney, NSW, Australia
| | - Kristy L Jackson
- Neuropharmacology Laboratory, Baker Heart and Diabetes Institute, Melbourne, VIC, Australia.,Drug Discovery Biology, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, VIC, Australia
| | - James L J Coleman
- Molecular Pharmacology Laboratory, Victor Chang Cardiac Research Institute, Sydney, NSW, Australia.,St Vincent's Clinical School, UNSW Sydney, Sydney, NSW, Australia.,Molecular Cardiology and Biophysics Division, Victor Chang Cardiac Research Institute, Sydney, NSW, Australia
| | - Madeleine R Paterson
- Neuropharmacology Laboratory, Baker Heart and Diabetes Institute, Melbourne, VIC, Australia
| | - Robert M Graham
- St Vincent's Clinical School, UNSW Sydney, Sydney, NSW, Australia.,Molecular Cardiology and Biophysics Division, Victor Chang Cardiac Research Institute, Sydney, NSW, Australia
| | - Geoffrey A Head
- Neuropharmacology Laboratory, Baker Heart and Diabetes Institute, Melbourne, VIC, Australia
| | - Nicola J Smith
- Molecular Pharmacology Laboratory, Victor Chang Cardiac Research Institute, Sydney, NSW, Australia.,St Vincent's Clinical School, UNSW Sydney, Sydney, NSW, Australia.,Molecular Cardiology and Biophysics Division, Victor Chang Cardiac Research Institute, Sydney, NSW, Australia
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21
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Macefield VG, Head GA. Editorial: Central Cardiovascular and Respiratory Control: New Techniques, New Directions, New Horizons. Front Physiol 2020; 11:617092. [PMID: 33329068 PMCID: PMC7710852 DOI: 10.3389/fphys.2020.617092] [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] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2020] [Accepted: 10/22/2020] [Indexed: 11/19/2022] Open
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22
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Sata Y, Burke SL, Gueguen C, Lim K, Watson AM, Jha JC, Eikelis N, Jackson KL, Lambert GW, Denton KM, Schlaich MP, Head GA. Contribution of the Renal Nerves to Hypertension in a Rabbit Model of Chronic Kidney Disease. Hypertension 2020; 76:1470-1479. [DOI: 10.1161/hypertensionaha.120.15769] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Overactivity of the sympathetic nervous system and high blood pressure are implicated in the development and progression of chronic kidney disease (CKD) and independently predict cardiovascular events in end-stage renal disease. To assess the role of renal nerves, we determined whether renal denervation (RDN) altered the hypertension and sympathoexcitation associated with a rabbit model of CKD. The model involves glomerular layer lesioning and uninephrectomy, resulting in renal function reduced by one-third and diuresis. After 3-week CKD, blood pressure was 13±2 mm Hg higher than at baseline (P<0.001), and compared with sham control rabbits, renal sympathetic nerve activity was 1.2±0.5 normalized units greater (P=0.01). The depressor response to ganglion blockade was also +8.0±3 mm Hg greater, but total norepinephrine spillover was 8.7±3.7 ng/min lower (bothP<0.05). RDN CKD rabbits only increased blood pressure by 8.0±1.5 mm Hg. Renal sympathetic activity, the response to ganglion blockade and diuresis were similar to sham denervated rabbits (non-CKD). CKD rabbits had intact renal sympathetic baroreflex gain and range, as well as normal sympathetic responses to airjet stress. However, hypoxia-induced sympathoexcitation was reduced by −9±0.4 normalized units. RDN did not alter the sympathetic response to hypoxia or airjet stress. CKD increased oxidative stress markers Nox5 and MCP-1 (monocyte chemoattractant protein-1) in the kidney, but RDN had no effect on these measures. Thus, RDN is an effective treatment for hypertension in this model of CKD without further impairing renal function or altering the normal sympathetic reflex responses to various environmental stimuli.
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Affiliation(s)
- Yusuke Sata
- From the Neuropharmacology Laboratory (Y.S., S.L.B., C.G., K.L., K.L.J., G.A.H.), Baker Heart and Diabetes Institute, Melbourne, VIC, Australia
- Human Neurotransmitters Laboratory (Y.S., M.P.S.), Baker Heart and Diabetes Institute, Melbourne, VIC, Australia
- Faculty of Medicine, Nursing and Health Sciences, Central Clinical School (Y.S.), Monash University, Melbourne, VIC, Australia
- Department of Cardiology, Alfred Hospital, Melbourne, VIC, Australia (Y.S.)
| | - Sandra L. Burke
- From the Neuropharmacology Laboratory (Y.S., S.L.B., C.G., K.L., K.L.J., G.A.H.), Baker Heart and Diabetes Institute, Melbourne, VIC, Australia
| | - Cindy Gueguen
- From the Neuropharmacology Laboratory (Y.S., S.L.B., C.G., K.L., K.L.J., G.A.H.), Baker Heart and Diabetes Institute, Melbourne, VIC, Australia
| | - Kyungjoon Lim
- From the Neuropharmacology Laboratory (Y.S., S.L.B., C.G., K.L., K.L.J., G.A.H.), Baker Heart and Diabetes Institute, Melbourne, VIC, Australia
- Department of Physiology, Anatomy and Microbiology, La Trobe University, Melbourne, VIC, Australia (K.L.)
| | - Anna M.D. Watson
- Department of Diabetes, Central Clinical School (A.M.D.W., J.C.J.), Monash University, Melbourne, VIC, Australia
| | - Jay C. Jha
- Department of Diabetes, Central Clinical School (A.M.D.W., J.C.J.), Monash University, Melbourne, VIC, Australia
| | - Nina Eikelis
- Iverson Health Innovation Research Institute and School of Health Science, Swinburne University of Technology, Hawthorn, VIC, Australia (N.E., G.W.L.)
| | - Kristy L. Jackson
- From the Neuropharmacology Laboratory (Y.S., S.L.B., C.G., K.L., K.L.J., G.A.H.), Baker Heart and Diabetes Institute, Melbourne, VIC, Australia
| | - Gavin W. Lambert
- Iverson Health Innovation Research Institute and School of Health Science, Swinburne University of Technology, Hawthorn, VIC, Australia (N.E., G.W.L.)
| | - Kate M. Denton
- Cardiovascular Program, Monash Biomedicine Discovery Institute and Department of Physiology, Monash University, Clayton, VIC, Australia (K.M.D.)
| | - Markus P. Schlaich
- Human Neurotransmitters Laboratory (Y.S., M.P.S.), Baker Heart and Diabetes Institute, Melbourne, VIC, Australia
- Dobney Hypertension Centre, School of Medicine, Royal Perth Hospital Unit, University of Western Australia (M.P.S.)
- Departments of Cardiology (M.P.S.), Royal Perth Hospital, Western Australia, Australia
- Nephrology (M.P.S.), Royal Perth Hospital, Western Australia, Australia
| | - Geoffrey A. Head
- From the Neuropharmacology Laboratory (Y.S., S.L.B., C.G., K.L., K.L.J., G.A.H.), Baker Heart and Diabetes Institute, Melbourne, VIC, Australia
- Department of Pharmacology (G.A.H.), Monash University, Melbourne, VIC, Australia
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23
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Gueguen C, Burke SL, Barzel B, Eikelis N, Watson AMD, Jha JC, Jackson KL, Sata Y, Lim K, Lambert GW, Jandeleit-Dahm KAM, Cooper ME, Thomas MC, Head GA. Empagliflozin modulates renal sympathetic and heart rate baroreflexes in a rabbit model of diabetes. Diabetologia 2020; 63:1424-1434. [PMID: 32372207 DOI: 10.1007/s00125-020-05145-0] [Citation(s) in RCA: 8] [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: 01/21/2020] [Accepted: 03/10/2020] [Indexed: 10/24/2022]
Abstract
AIMS/HYPOTHESIS We determined whether empagliflozin altered renal sympathetic nerve activity (RSNA) and baroreflexes in a diabetes model in conscious rabbits. METHODS Diabetes was induced by alloxan, and RSNA, mean arterial pressure (MAP) and heart rate were measured before and after 1 week of treatment with empagliflozin, insulin, the diuretic acetazolamide or the ACE inhibitor perindopril, or no treatment, in conscious rabbits. RESULTS Four weeks after alloxan administration, blood glucose was threefold and MAP 9% higher than non-diabetic controls (p < 0.05). One week of treatment with empagliflozin produced a stable fall in blood glucose (-43%) and increased water intake (+49%) but did not change RSNA, MAP or heart rate compared with untreated diabetic rabbits. The maximum RSNA to hypotension was augmented by 75% (p < 0.01) in diabetic rabbits but the heart rate baroreflex was unaltered. Empagliflozin and acetazolamide reduced the augmentation of the RSNA baroreflex (p < 0.05) to be similar to the non-diabetic group. Noradrenaline (norepinephrine) spillover was similar in untreated diabetic and non-diabetic rabbits but twofold greater in empagliflozin- and acetazolamide-treated rabbits (p < 0.05). CONCLUSIONS/INTERPRETATION As empagliflozin can restore diabetes-induced augmented sympathetic reflexes, this may be beneficial in diabetic patients. A similar action of the diuretic acetazolamide suggests that the mechanism may involve increased sodium and water excretion. Graphical abstract.
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Affiliation(s)
- Cindy Gueguen
- Neuropharmacology Laboratory, Baker Heart and Diabetes Institute, P.O. Box 6492, Melbourne, VIC, 3004, Australia
| | - Sandra L Burke
- Neuropharmacology Laboratory, Baker Heart and Diabetes Institute, P.O. Box 6492, Melbourne, VIC, 3004, Australia
| | - Benjamin Barzel
- Neuropharmacology Laboratory, Baker Heart and Diabetes Institute, P.O. Box 6492, Melbourne, VIC, 3004, Australia
| | - Nina Eikelis
- Iverson Health Innovation Research Institute and School of Health Science, Swinburne University of Technology, Melbourne, VIC, Australia
| | - Anna M D Watson
- Department of Diabetes, Central Clinical School, Monash University, Melbourne, VIC, Australia
| | - Jay C Jha
- Department of Diabetes, Central Clinical School, Monash University, Melbourne, VIC, Australia
| | - Kristy L Jackson
- Neuropharmacology Laboratory, Baker Heart and Diabetes Institute, P.O. Box 6492, Melbourne, VIC, 3004, Australia
| | - Yusuke Sata
- Neuropharmacology Laboratory, Baker Heart and Diabetes Institute, P.O. Box 6492, Melbourne, VIC, 3004, Australia
- Central Clinical School, Faculty of Medicine, Nursing and Health Sciences, Monash University, Melbourne, VIC, Australia
| | - Kyungjoon Lim
- Neuropharmacology Laboratory, Baker Heart and Diabetes Institute, P.O. Box 6492, Melbourne, VIC, 3004, Australia
- Department of Physiology, Anatomy & Microbiology, La Trobe University, Melbourne, VIC, Australia
| | - Gavin W Lambert
- Iverson Health Innovation Research Institute and School of Health Science, Swinburne University of Technology, Melbourne, VIC, Australia
| | - Karin A M Jandeleit-Dahm
- Department of Diabetes, Central Clinical School, Monash University, Melbourne, VIC, Australia
- Diabetic Nephropathy Research Group, Institute for Clinical Diabetology, German Diabetes Center (DDZ), Leibnitz Center for Diabetes Research, Heinrich Heine University, Düsseldorf, Germany
| | - Mark E Cooper
- Department of Diabetes, Central Clinical School, Monash University, Melbourne, VIC, Australia
- Baker Heart and Diabetes Institute, Melbourne, VIC, Australia
| | - Merlin C Thomas
- Department of Diabetes, Central Clinical School, Monash University, Melbourne, VIC, Australia
| | - Geoffrey A Head
- Neuropharmacology Laboratory, Baker Heart and Diabetes Institute, P.O. Box 6492, Melbourne, VIC, 3004, Australia.
- Department of Pharmacology, Monash University, Melbourne, VIC, Australia.
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24
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Jackson KL, Gueguen C, Lim K, Eikelis N, Stevenson ER, Charchar FJ, Lambert GW, Burke SL, Paterson MR, Marques FZ, Head GA. Neural suppression of miRNA-181a in the kidney elevates renin expression and exacerbates hypertension in Schlager mice. Hypertens Res 2020; 43:1152-1164. [PMID: 32427944 DOI: 10.1038/s41440-020-0453-x] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [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: 02/18/2020] [Revised: 04/05/2020] [Accepted: 04/14/2020] [Indexed: 11/09/2022]
Abstract
BPH/2J mice are a genetic model of hypertension with overactivity of the sympathetic nervous system (SNS) and renin-angiotensin system (RAS). BPH/2J display higher renal renin mRNA and low levels of its negative regulator microRNA-181a (miR-181a). We hypothesise that high renal SNS activity may reduce miR-181a expression, which contributes to elevated RAS activity and hypertension in BPH/2J. Our aim was to determine whether in vivo administration of a renal-specific miR-181a mimic or whether renal denervation could increase renal miR-181a abundance to reduce renal renin mRNA, RAS activity and hypertension in BPH/2J mice. Blood pressure (BP) in BPH/2J and normotensive BPN/3J mice was measured via radiotelemetry probes. Mice were administered miR-181a mimic or a negative control (1-25 nmol, i.v., n = 6-10) with BP measured for 48 h after each dose or they underwent renal denervation or sham surgery (n = 7-9). Injection of 5-25 nmol miR-181a mimic reduced BP in BPH/2J mice after 36-48 h (-5.3 ± 1.8, -6.1 ± 1.9 mmHg, respectively, P < 0.016). Treatment resulted in lower renal renin and inflammatory marker (TLR4) mRNA levels in BPH/2J. The mimic abolished the hypotensive effect of blocking the RAS with enalaprilat (P < 0.01). No differences between mimic or vehicle were observed in BPN/3J mice except for a higher level of renal angiotensinogen in the mimic-treated mice. Renal miR-181a levels that were lower in sham BPH/2J mice were greater following renal denervation and were thus similar to those of BPN/3J. Our findings suggest that the reduced renal miR-181a may partially contribute to the elevated BP in BPH/2J mice, through an interaction between the renal sympathetic nerves and miR-181a regulation of the RAS.
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Affiliation(s)
- Kristy L Jackson
- Neuropharmacology Laboratory, Baker Heart and Diabetes Institute, Melbourne, VIC, Australia
| | - Cindy Gueguen
- Neuropharmacology Laboratory, Baker Heart and Diabetes Institute, Melbourne, VIC, Australia
| | - Kyungjoon Lim
- Neuropharmacology Laboratory, Baker Heart and Diabetes Institute, Melbourne, VIC, Australia.,Department of Physiology, Anatomy & Microbiology, School of Life Sciences, La Trobe University, Melbourne, VIC, Australia
| | - Nina Eikelis
- Human Neurotransmitters Laboratory, Baker Heart and Diabetes Institute, Melbourne, VIC, Australia.,Iverson Health Innovation Research Institute, Swinburne University of Technology, Hawthorn, VIC, Australia
| | - Emily R Stevenson
- Neuropharmacology Laboratory, Baker Heart and Diabetes Institute, Melbourne, VIC, Australia
| | - Fadi J Charchar
- Faculty of Science and Technology, Federation University Australia, Ballarat, VIC, Australia
| | - Gavin W Lambert
- Human Neurotransmitters Laboratory, Baker Heart and Diabetes Institute, Melbourne, VIC, Australia.,Iverson Health Innovation Research Institute, Swinburne University of Technology, Hawthorn, VIC, Australia
| | - Sandra L Burke
- Neuropharmacology Laboratory, Baker Heart and Diabetes Institute, Melbourne, VIC, Australia
| | - Madeleine R Paterson
- Hypertension Research Laboratory, School of Biological Sciences, Monash University, Clayton, VIC, Australia
| | - Francine Z Marques
- Faculty of Science and Technology, Federation University Australia, Ballarat, VIC, Australia.,Hypertension Research Laboratory, School of Biological Sciences, Monash University, Clayton, VIC, Australia.,Heart Failure Research Group, Baker Heart and Diabetes Institute, Melbourne, VIC, Australia
| | - Geoffrey A Head
- Neuropharmacology Laboratory, Baker Heart and Diabetes Institute, Melbourne, VIC, Australia. .,Department of Pharmacology, Monash University, Clayton, VIC, Australia.
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25
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Affiliation(s)
- Geoffrey A Head
- Baker Heart and Diabetes Institute, Melbourne, VIC, Australia
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26
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Gueguen C, Burke SL, Barzel B, Lim K, Eikelis N, Watson AM, Jha JC, Jackson KL, Sata Y, Lambert GW, Jandeleit-Dahm KA, Cooper ME, Thomas MC, Head GA. Treatment with SGLT2 Inhibitor Empagliflozin Modulates Renal Sympathetic Nerve Activity in Diabetic Rabbits. FASEB J 2020. [DOI: 10.1096/fasebj.2020.34.s1.04880] [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)
| | | | | | | | - Nina Eikelis
- Iverson Health Innovation Research Institute and School of Health Science Swinburne University of Technology
| | | | - Jay C. Jha
- Central Clinical School Monash University
| | | | | | - Gavin W. Lambert
- Iverson Health Innovation Research Institute and School of Health Science Swinburne University of Technology
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27
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Gueguen C, Le-Pham PN, Jackson KL, Paterson MR, Esler M, Marques FZ, Lambert E, Head GA. Hypotensive Effects of Ganaxolone are Associated with an Upregulation of GABA
A
Receptor Subunit Expression in Male Hypertensive Schlager Mice. FASEB J 2020. [DOI: 10.1096/fasebj.2020.34.s1.04950] [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)
| | | | | | | | | | | | - Elisabeth Lambert
- Iverson Health Innovation Research Institute and School of Health Science Swinburne University of Technology
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28
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Herat LY, Magno AL, Kiuchi MG, Jackson KL, Carnagarin R, Head GA, Schlaich MP, Matthews VB. The Schlager mouse as a model of altered retinal phenotype. Neural Regen Res 2020; 15:512-518. [PMID: 31571663 PMCID: PMC6921339 DOI: 10.4103/1673-5374.266069] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [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] [Indexed: 12/03/2022] Open
Abstract
Hypertension is a risk factor for a large number of vision-threatening eye disorders. In this study, we investigated for the first time the retinal neural structure of the hypertensive BPH/2J mouse (Schlager mouse) and compared it to its control counterpart, the normotensive BPN/3J strain. The BPH/2J mouse is a selectively inbred mouse strain that develops chronic hypertension due to elevated sympathetic nervous system activity. When compared to the BPN/3J strain, the hypertensive BPH/2J mice showed a complete loss of outer layers of the neural retina at 21 weeks of age, which was indicative of a severe vision-threatening disease potentially caused by hypertension. To elucidate whether the retinal neural phenotype in the BPH/2J strain was attributed to increased BP, we investigated the neural retina of both BPN/3J and BPH/2J mice at 4 weeks of age. Our preliminary results showed for the first time that the BPH/2J strain develops severe retinal neural damage at a young age. Our findings suggest that the retinal phenotype in the BPH/2J mouse is possibly due to elevated blood pressure and may be contributed by an early onset spontaneous mutation which is yet to be identified or a congenital defect occurring in this strain. Further characterization of the BPH/2J mouse strain is likely to i) elucidate gene defects underlying retinal disease; ii) understand mechanisms leading to neural retinal disease and iii) permit testing of molecules for translational research to interfere with the progression of retinal disease. The animal experiments were performed with the approval of the Royal Perth Hospital Animal Ethics Committee (R535/17-18) on June 1, 2017.
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Affiliation(s)
- Lakshini Y Herat
- Dobney Hypertension Centre, School of Biomedical Science - Royal Perth Hospital Unit, University of Western Australia, Perth, Australia
| | - Aaron L Magno
- Research Centre, Royal Perth Hospital, Perth, Australia
| | - Márcio G Kiuchi
- Dobney Hypertension Centre, School of Medicine - Royal Perth Hospital Unit, University of Western Australia, Perth, Australia
| | - Kristy L Jackson
- Neuropharmacology Laboratory, Baker Heart and Diabetes Institute, Melbourne, Australia
| | - Revathy Carnagarin
- Dobney Hypertension Centre, School of Medicine - Royal Perth Hospital Unit, University of Western Australia, Perth, Australia
| | - Geoffrey A Head
- Neuropharmacology Laboratory, Baker Heart and Diabetes Institute, Melbourne, Australia
| | - Markus P Schlaich
- Dobney Hypertension Centre, School of Medicine - Royal Perth Hospital Unit, University of Western Australia; Department of Cardiology and Department of Nephrology, Royal Perth Hospital, Perth, Australia
| | - Vance B Matthews
- Dobney Hypertension Centre, School of Biomedical Science - Royal Perth Hospital Unit, University of Western Australia, Perth, Australia
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Abstract
The sympathetic nervous system (SNS) contribution to long-term setting of blood pressure (BP) and hence hypertension has been a continuing controversy over many decades. However, the contribution of increased sympathetic vasomotor tone to the heart, kidney, and blood vessels has been suggested as a major influence on the development of high BP which affects 30-40% of the population. This is relevant to hypertension associated with chronic stress, being overweight or obese as well to chronic kidney disease. Treatments that have attempted to block the peripheral aspects of the SNS contribution have included surgery to cut the sympathetic nerves as well as agents to block α- and β-adrenoceptors. Other treatments, such as centrally acting drugs like clonidine, rilmenidine, or moxonidine, activate receptors within the ventrolateral medulla to reduce the vasomotor tone overall but have side effects that limit their use. None of these treatments target the cause of the enhanced sympathetic tone. Recently we have identified an antihypertensive action of the neurosteroid allopregnanolone in a mouse model of neurogenic hypertension. Allopregnanolone is known to facilitate high-affinity extra-synaptic γ-aminobutyric acid A receptors (GABAAR) through allosteric modulation and transcriptional upregulation. The antihypertensive effect was specific for increased expression of δ subunits in the amygdala and hypothalamus. This focused review examines the possibility that neurosteroids may be a novel therapeutic approach to address the neurogenic contribution to hypertension. We discuss the causes and prevalence of neurogenic hypertension, current therapeutic approaches, and the applicability of using neurosteroids as antihypertensive therapy.
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Affiliation(s)
- Geoffrey A Head
- Neuropharmacology Laboratory, Baker Heart and Diabetes Institute, Melbourne, VIC, Australia
| | - Kristy L Jackson
- Neuropharmacology Laboratory, Baker Heart and Diabetes Institute, Melbourne, VIC, Australia
| | - Cindy Gueguen
- Neuropharmacology Laboratory, Baker Heart and Diabetes Institute, Melbourne, VIC, Australia
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Stergiou GS, Parati G, McManus RJ, Head GA, Myers MG, Whelton PK. Guidelines for blood pressure measurement: development over 30 years. J Clin Hypertens (Greenwich) 2019; 20:1089-1091. [PMID: 30003695 DOI: 10.1111/jch.13295] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [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: 03/24/2018] [Accepted: 03/26/2018] [Indexed: 12/01/2022]
Abstract
In the last 2 decades, several scientific societies have published specific guidelines for blood pressure (BP) measurement, providing detailed recommendations for office, home, and ambulatory BP monitoring. These documents typically provided strong support for using out-of-office BP monitoring (ambulatory and home). More recently, several organizations recommended out-of-office BP evaluation as a primary method for diagnosing hypertension and for treatment titration, with office BP regarded as a screening method. Efforts should now be directed towards making ambulatory and home BP monitoring readily available in primary care and ensuring that such measurements are obtained by following current guidelines. Moreover, it should be mandatory for all published clinical research papers on hypertension to provide details on the methodology of the BP measurement.
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Affiliation(s)
- George S Stergiou
- Hypertension Center STRIDE-7, School of Medicine, Third Department of Medicine, Sotiria Hospital, National and Kapodistrian University of Athens, Athens, Greece
| | - Gianfranco Parati
- Department of Medicine and Surgery, University of Milano-Bicocca, Milano, Italy.,Cardiology Unit, Department of Cardiovascular, Neural, and Metabolic Sciences, Istituto Auxologco Italiano, S. Luca Hospital, Milano, Italy
| | - Richard J McManus
- Nuffield Department of Primary Care Health Sciences, Green Templeton College, University of Oxford, Oxford, UK
| | - Geoffrey A Head
- Baker Heart and Diabetes Institute, Melbourne, Vic, Australia
| | - Martin G Myers
- Division of Cardiology, Schulich Heart Program, Sunnybrook Health Sciences Centre, University of Toronto, Toronto, ON, Canada
| | - Paul K Whelton
- Department of Epidemiology, Tulane University School of Public Health and Tropical Medicine, New Orleans, LA, USA
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31
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Lambert GW, Head GA, Chen WS, Hamer M, Malan NT, Quinn S, Schlaich MP, Malan L. Ambulatory blood pressure monitoring and morning surge in blood pressure in adult black and white South Africans. J Clin Hypertens (Greenwich) 2019; 22:21-28. [PMID: 31769175 DOI: 10.1111/jch.13740] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [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: 07/15/2019] [Revised: 09/24/2019] [Accepted: 10/07/2019] [Indexed: 12/01/2022]
Abstract
We examined whether there were differences in the circadian variation in blood pressure and the morning surge in blood pressure between black and white Africans. Clinic and ambulatory blood pressure data obtained from the Sympathetic Activity and Ambulatory Blood Pressure in Africans (SABPA) study was examined (n = 406; 49% black African). Ambulatory blood pressure readings were fitted to a six-parameter double logistic equation to determine the power and rate of the morning surge in blood pressure. Multiple linear regression analysis was used to examine differences in blood pressure between black and white participants. Clinic and ambulatory blood pressure were higher in black participants throughout the day and night. In those taking medications, blood pressure was less well controlled in black subjects. Despite the higher systolic blood pressure, the day-night difference estimated by the logistic function was similar in black and white participants. However, the rate of rise and power in the morning surge in blood pressure was lower in black participants. We conclude that black participants of the SABPA study present with higher blood pressure throughout the day and night but have a lower power of the morning surge in blood pressure due to a slower morning rate of increase. Moreover, they had an increased prevalence of undiagnosed hypertension and, in those taking medication, were less likely to have their blood pressure controlled than their white counterparts.
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Affiliation(s)
- Gavin W Lambert
- Iverson Health Innovation Research Institute, Swinburne University of Technology, Melbourne, Vic., Australia.,School of Health Science, Swinburne University of Technology, Melbourne, Vic., Australia.,Human Neurotransmitters Laboratory, Baker Heart and Diabetes Institute, Melbourne, Vic., Australia
| | - Geoffrey A Head
- Neuropharmacology Laboratory, Baker Heart and Diabetes Institute, Melbourne, Vic., Australia
| | - Won Sun Chen
- Department of Statistics, Data Science and Epidemiology, Swinburne University of Technology, Melbourne, Vic., Australia
| | - Mark Hamer
- School Sport, Exercise & Health Sciences, Loughborough University, Loughborough, UK
| | - Nicolaas T Malan
- Hypertension in Africa Research Team (HART), North-West University, Potchefstroom, South Africa
| | - Stephen Quinn
- Department of Statistics, Data Science and Epidemiology, Swinburne University of Technology, Melbourne, Vic., Australia
| | - Markus P Schlaich
- Neurovascular Hypertension and Kidney Disease Laboratory, Baker Heart and Diabetes Institute, Melbourne, Vic, Australia.,Royal Perth Hospital Unit, Dobney Hypertension Centre, School of Medicine, University of Western Australia, Perth, WA, Australia
| | - Leone Malan
- Hypertension in Africa Research Team (HART), North-West University, Potchefstroom, South Africa
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Jackson KL, Head GA, Gueguen C, Stevenson ER, Lim K, Marques FZ. Mechanisms Responsible for Genetic Hypertension in Schlager BPH/2 Mice. Front Physiol 2019; 10:1311. [PMID: 31681017 PMCID: PMC6813185 DOI: 10.3389/fphys.2019.01311] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [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: 08/30/2019] [Accepted: 09/30/2019] [Indexed: 01/18/2023] Open
Abstract
It has been 45 years since Gunther Schlager used a cross breeding program in mice to develop inbred strains with high, normal, and low blood pressure (BPH/2, BPN/3, and BPL/1 respectively). Thus, it is timely to gather together the studies that have characterized and explored the mechanisms associated with the hypertension to take stock of exactly what is known and what remains to be determined. Growing evidence supports the notion that the mechanism of hypertension in BPH/2 mice is predominantly neurogenic with some of the early studies showing aberrant brain noradrenaline levels in BPH/2 compared with BPN/3. Analysis of the adrenal gland using microarray suggested an association with the activity of the sympathetic nervous system. Indeed, in support of this, there is a larger depressor response to ganglion blockade, which reduced blood pressure in BPH/2 mice to the same level as BPN/3 mice. Greater renal tyrosine hydroxylase staining and greater renal noradrenaline levels in BPH/2 mice suggest sympathetic hyperinnervation of the kidney. Renal denervation markedly reduced the blood pressure in BPH/2 but not BPN/3 mice, confirming the importance of renal sympathetic nervous activity contributing to the hypertension. Further, there is an important contribution to the hypertension from miR-181a and renal renin in this strain. BPH/2 mice also display greater neuronal activity of amygdalo-hypothalamic cardiovascular regulatory regions. Lesions of the medial nucleus of the amygdala reduced the hypertension in BPH/2 mice and abolished the strain difference in the effect of ganglion blockade, suggesting a sympathetic mechanism. Further studies suggest that aberrant GABAergic inhibition may play a role since BPH/2 mice have low GABAA receptor δ, α4 and β2 subunit mRNA expression in the hypothalamus, which are predominantly involved in promoting tonic neuronal inhibition. Allopregnanolone, an allosteric modulator of GABAA receptors, which increase the expression of these subunits in the amygdala and hypothalamus, is shown to reduce the hypertension and sympathetic nervous system contribution in BPH/2 mice. Thus far, evidence suggests that BPH/2 mice have aberrant GABAergic inhibition, which drives neuronal overactivity within amygdalo-hypothalamic brain regions. This overactivity is responsible for the greater sympathetic contribution to the hypertension in BPH/2 mice, thus making this an ideal model of neurogenic hypertension.
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Affiliation(s)
- Kristy L Jackson
- Neuropharmacology Laboratory, Baker Heart and Diabetes Institute, Melbourne, VIC, Australia
| | - Geoffrey A Head
- Neuropharmacology Laboratory, Baker Heart and Diabetes Institute, Melbourne, VIC, Australia
| | - Cindy Gueguen
- Neuropharmacology Laboratory, Baker Heart and Diabetes Institute, Melbourne, VIC, Australia
| | - Emily R Stevenson
- Neuropharmacology Laboratory, Baker Heart and Diabetes Institute, Melbourne, VIC, Australia
| | - Kyungjoon Lim
- Neuropharmacology Laboratory, Baker Heart and Diabetes Institute, Melbourne, VIC, Australia.,Department of Physiology, Anatomy and Microbiology, School of Life Sciences, La Trobe University, Melbourne, VIC, Australia
| | - Francine Z Marques
- Neuropharmacology Laboratory, Baker Heart and Diabetes Institute, Melbourne, VIC, Australia.,Hypertension Research Laboratory, School of Biological Sciences, Monash University, Clayton, VIC, Australia
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33
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Sari CI, Eikelis N, Head GA, Schlaich M, Meikle P, Lambert G, Lambert E. Android Fat Deposition and Its Association With Cardiovascular Risk Factors in Overweight Young Males. Front Physiol 2019; 10:1162. [PMID: 31620011 PMCID: PMC6759693 DOI: 10.3389/fphys.2019.01162] [Citation(s) in RCA: 28] [Impact Index Per Article: 5.6] [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: 06/13/2019] [Accepted: 08/28/2019] [Indexed: 11/16/2022] Open
Abstract
Objective Excess adiposity increases the risk of type-2 diabetes and cardiovascular disease development. Beyond the simple level of adiposity, the pattern of fat distribution may influence these risks. We sought to examine if higher android fat distribution was associated with different hemodynamic, metabolic or vascular profile compared to a lower accumulation of android fat deposits in young overweight males. Methods Forty-six participants underwent dual-energy X-ray absorptiometry and were stratified into two groups. Group 1: low level of android fat (<9.5%) and group 2: high level of android fat (>9.5%). Assessments comprised measures of plasma lipid and glucose profile, blood pressure, endothelial function [reactive hyperemia index (RHI)] and muscle sympathetic nerve activity (MSNA). Results There were no differences in weight, BMI, total body fat and lean mass between the two groups. Glucose tolerance and insulin resistance (fasting plasma insulin) were impaired in group 2 (p < 0.05). Levels of plasma triglycerides and 5 lipid species were higher in group 2 (p < 0.05). Endothelial function was less in group 2 (RHI: 1.64 vs. 2.26, p = 0.003) and heart rate was higher (76 vs. 67 bpm, p = 0.004). No difference occurred in MSNA nor blood pressure between the 2 groups. Conclusion Preferential fat accumulation in the android compartment is associated with increased cardiovascular and metabolic risk via alteration of endothelial function.
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Affiliation(s)
- Carolina Ika Sari
- Human Neurotransmitters Laboratory, Baker Heart and Diabetes Institute, Melbourne, VIC, Australia
| | - Nina Eikelis
- Human Neurotransmitters Laboratory, Baker Heart and Diabetes Institute, Melbourne, VIC, Australia.,Iverson Health Innovation Research Institute, School of Health Sciences, Faculty of Health, Arts and Design, Swinburne University of Technology, Hawthorn, VIC, Australia
| | - Geoffrey A Head
- Neuropharmacology Laboratory, Baker Heart and Diabetes Institute, Melbourne, VIC, Australia
| | - Markus Schlaich
- Dobney Hypertension Centre, School of Medicine - Royal Perth Hospital Unit, The University of Western Australia, Perth, WA, Australia
| | - Peter Meikle
- Metabolomics Laboratories, Baker Heart and Diabetes Institute, Melbourne, VIC, Australia
| | - Gavin Lambert
- Human Neurotransmitters Laboratory, Baker Heart and Diabetes Institute, Melbourne, VIC, Australia.,Iverson Health Innovation Research Institute, School of Health Sciences, Faculty of Health, Arts and Design, Swinburne University of Technology, Hawthorn, VIC, Australia
| | - Elisabeth Lambert
- Human Neurotransmitters Laboratory, Baker Heart and Diabetes Institute, Melbourne, VIC, Australia.,Iverson Health Innovation Research Institute, School of Health Sciences, Faculty of Health, Arts and Design, Swinburne University of Technology, Hawthorn, VIC, Australia
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34
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Watson AMD, Gould EAM, Penfold SA, Lambert GW, Pratama PR, Dai A, Gray SP, Head GA, Jandeleit-Dahm KA. Diabetes and Hypertension Differentially Affect Renal Catecholamines and Renal Reactive Oxygen Species. Front Physiol 2019; 10:309. [PMID: 31040788 PMCID: PMC6477025 DOI: 10.3389/fphys.2019.00309] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [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: 11/23/2018] [Accepted: 03/07/2019] [Indexed: 01/11/2023] Open
Abstract
Patients with diabetic hypertensive nephropathy have accelerated disease progression. Diabetes and hypertension have both been associated with changes in renal catecholamines and reactive oxygen species. With a specific focus on renal catecholamines and oxidative stress we examined a combined model of hypertension and diabetes using normotensive BPN/3J and hypertensive BPH/2J Schlager mice. Induction of diabetes (5 × 55 mg/kg streptozotocin i.p.) did not change the hypertensive status of BPH/2J mice (telemetric 24 h avg. MAP, non-diabetic 131 ± 2 vs. diabetic 129 ± 1 mmHg, n.s at 9 weeks of study). Diabetes-associated albuminuria was higher in BPH/2J vs. diabetic BPN/3J (1205 + 196/-169 versus 496 + 67/-59 μg/24 h, p = 0.008). HPLC measurement of renal cortical norepinephrine and dopamine showed significantly greater levels in hypertensive mice whilst diabetes was associated with significantly lower catecholamine levels. Diabetic BPH/2J also had greater renal catecholamine levels than diabetic BPN/3J (diabetic: norepinephrine BPN/3J 40 ± 4, BPH/2J 91 ± 5, p = 0.010; dopamine: BPN/3J 2 ± 1; BPH/2J 3 ± 1 ng/mg total protein, p < 0.001 after 10 weeks of study). Diabetic BPH/2J showed greater cortical tubular immunostaining for monoamine oxidase A and cortical mitochondrial hydrogen peroxide formation was greater in both diabetic and non-diabetic BPH/2J. While cytosolic catalase activity was greater in non-diabetic BPH/2J it was significantly lower in diabetic BPH/2J (cytosolic: BPH/2J 127 ± 12 vs. 63 ± 6 nmol/min/ml, p < 0.001). We conclude that greater levels of renal norepinephrine and dopamine associated with hypertension, together with diabetes-associated compromised anti-oxidant systems, contribute to increased renal oxidative stress in diabetes and hypertension. Elevations in renal cortical catecholamines and reactive oxygen species have important therapeutic implications for hypertensive diabetic patients.
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Affiliation(s)
- Anna M D Watson
- Department of Diabetes, Central Clinical School, Faculty of Medicine, Nursing and Health Sciences, Monash University, Melbourne, VIC, Australia.,Baker Heart and Diabetes Institute, Melbourne, VIC, Australia
| | | | - Sally A Penfold
- Baker Heart and Diabetes Institute, Melbourne, VIC, Australia
| | - Gavin W Lambert
- Baker Heart and Diabetes Institute, Melbourne, VIC, Australia.,Iverson Health Innovation Research Institute, Faculty of Health, Arts and Design, Swinburne University of Technology, Hawthorn, VIC, Australia
| | | | - Aozhi Dai
- Department of Diabetes, Central Clinical School, Faculty of Medicine, Nursing and Health Sciences, Monash University, Melbourne, VIC, Australia
| | - Stephen P Gray
- Baker Heart and Diabetes Institute, Melbourne, VIC, Australia
| | - Geoffrey A Head
- Baker Heart and Diabetes Institute, Melbourne, VIC, Australia
| | - Karin A Jandeleit-Dahm
- Department of Diabetes, Central Clinical School, Faculty of Medicine, Nursing and Health Sciences, Monash University, Melbourne, VIC, Australia.,Baker Heart and Diabetes Institute, Melbourne, VIC, Australia
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Gueguen C, Jackson KL, Marques FZ, Eikelis N, Phillips S, Stevenson ER, Charchar FJ, Lambert GW, Davern PJ, Head GA. Renal nerves contribute to hypertension in Schlager BPH/2J mice. Hypertens Res 2018; 42:306-318. [PMID: 30531841 DOI: 10.1038/s41440-018-0147-9] [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] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2018] [Revised: 07/30/2018] [Accepted: 08/22/2018] [Indexed: 01/29/2023]
Abstract
Schlager mice (BPH/2J) are hypertensive due to a greater contribution of the sympathetic nervous system (SNS) and renin-angiotensin system (RAS). The kidneys of BPH/2J are hyper-innervated suggesting renal nerves may contribute to the hypertension. We therefore determined the effect of bilateral renal denervation (RD) on hypertension in BPH/2J. Mean arterial pressure (MAP) was measured by radiotelemetry before and for 3 weeks after RD in BPH/2J and BPN/3J. The effects of pentolinium and enalaprilat were examined to determine the contribution of the SNS and RAS, respectively. After 3 weeks, MAP was -10.9 ± 2.1 mmHg lower in RD BPH/2J compared to baseline and -2.1 ± 2.2 mmHg in sham BPH/2J (P < 0.001, n = 8-10). RD had no effect in BPN/3J (P > 0.1). The depressor response to pentolinium was greater in BPH/2J than BPN/3J, but in both cases the response in RD mice was similar to sham. Enalaprilat decreased MAP more in RD BPH/2J compared to sham (-12 vs -3 mmHg, P < 0.001) but had no effect in BPN/3J. RD reduced renal noradrenaline in both strains but more so in BPH/2J. RD reduced renin mRNA and protein, but not plasma renin in BPH/2J to levels comparable with BPN/3J mice. We conclude that renal nerves contribute to hypertension in BPH mice as RD induced a sustained fall in MAP, which was associated with a reduction of intrarenal renin expression. The lack of inhibition of the depressor effects of pentolinium and enalaprilat by RD suggests that vasoconstrictor effects of the SNS or RAS are not involved.
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Affiliation(s)
- Cindy Gueguen
- Neuropharmacology Laboratory, Baker Heart and Diabetes Institute, Melbourne, Australia
| | - Kristy L Jackson
- Neuropharmacology Laboratory, Baker Heart and Diabetes Institute, Melbourne, Australia
| | - Francine Z Marques
- Heart Failure Research Group, Baker Heart and Diabetes Institute, Melbourne, Australia.,Department of Pharmacology Monash University, Melbourne, Australia
| | - Nina Eikelis
- Human Neurotransmitters Laboratory, Baker Heart and Diabetes Institute, Melbourne, Australia.,Iverson Health Innovation Research Institute, Swinburne University of Technology, Hawthorn, Australia
| | - Sarah Phillips
- Human Neurotransmitters Laboratory, Baker Heart and Diabetes Institute, Melbourne, Australia.,Iverson Health Innovation Research Institute, Swinburne University of Technology, Hawthorn, Australia
| | - Emily R Stevenson
- Neuropharmacology Laboratory, Baker Heart and Diabetes Institute, Melbourne, Australia
| | - Fadi J Charchar
- Faculty of Science and Technology, Federation University Australia, Ballarat, Victoria, Australia
| | - Gavin W Lambert
- Human Neurotransmitters Laboratory, Baker Heart and Diabetes Institute, Melbourne, Australia.,Iverson Health Innovation Research Institute, Swinburne University of Technology, Hawthorn, Australia
| | - Pamela J Davern
- Neuropharmacology Laboratory, Baker Heart and Diabetes Institute, Melbourne, Australia
| | - Geoffrey A Head
- Neuropharmacology Laboratory, Baker Heart and Diabetes Institute, Melbourne, Australia. .,Department of Pharmacology Monash University, Melbourne, Australia.
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Sata Y, Head GA, Esler MD, Schlaich MP. Reply. J Hypertens 2018; 36:1606-1607. [PMID: 29847455 DOI: 10.1097/hjh.0000000000001765] [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: 11/25/2022]
Affiliation(s)
- Yusuke Sata
- Neurovascular Hypertension and Kidney Disease Laboratory.,Faculty of Medicine, Nursing and Health Sciences, Monash University, Melbourne, Victoria
| | - Geoffrey A Head
- Neuropharmacology Laboratory, Baker Heart and Diabetes Institute
| | - Murray D Esler
- Neurovascular Hypertension and Kidney Disease Laboratory.,Department of Cardiovascular Medicine, Alfred Hospital
| | - Markus P Schlaich
- Neurovascular Hypertension and Kidney Disease Laboratory.,Department of Cardiovascular Medicine, Alfred Hospital.,Faculty of Medicine, Nursing and Health Sciences, Monash University, Melbourne, Victoria.,Royal Perth Hospital Unit, Dobney Hypertension Centre, School of Medicine, University of Western Australia, Perth, Western Australia, Australia
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37
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Sata Y, Head GA, Denton K, May CN, Schlaich MP. Role of the Sympathetic Nervous System and Its Modulation in Renal Hypertension. Front Med (Lausanne) 2018; 5:82. [PMID: 29651418 PMCID: PMC5884873 DOI: 10.3389/fmed.2018.00082] [Citation(s) in RCA: 85] [Impact Index Per Article: 14.2] [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: 01/12/2018] [Accepted: 03/15/2018] [Indexed: 12/18/2022] Open
Abstract
The kidneys are densely innervated with renal efferent and afferent nerves to communicate with the central nervous system. Innervation of major structural components of the kidneys, such as blood vessels, tubules, the pelvis, and glomeruli, forms a bidirectional neural network to relay sensory and sympathetic signals to and from the brain. Renal efferent nerves regulate renal blood flow, glomerular filtration rate, tubular reabsorption of sodium and water, as well as release of renin and prostaglandins, all of which contribute to cardiovascular and renal regulation. Renal afferent nerves complete the feedback loop via central autonomic nuclei where the signals are integrated and modulate central sympathetic outflow; thus both types of nerves form integral parts of the self-regulated renorenal reflex loop. Renal sympathetic nerve activity (RSNA) is commonly increased in pathophysiological conditions such as hypertension and chronic- and end-stage renal disease. Increased RSNA raises blood pressure and can contribute to the deterioration of renal function. Attempts have been made to eliminate or interfere with this important link between the brain and the kidneys as a neuromodulatory treatment for these conditions. Catheter-based renal sympathetic denervation has been successfully applied in patients with resistant hypertension and was associated with significant falls in blood pressure and renal protection in most studies performed. The focus of this review is the neural contribution to the control of renal and cardiovascular hemodynamics and renal function in the setting of hypertension and chronic kidney disease, as well as the specific roles of renal efferent and afferent nerves in this scenario and their utility as a therapeutic target.
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Affiliation(s)
- Yusuke Sata
- Neurovascular Hypertension and Kidney Disease Laboratory, Baker Heart and Diabetes Institute, Melbourne, VIC, Australia.,Faculty of Medicine, Nursing and Health Sciences, Central Clinical School, Monash University, Melbourne, VIC, Australia
| | - Geoffrey A Head
- Neuropharmacology Laboratory, Baker Heart and Diabetes Institute, Melbourne, VIC, Australia
| | - Kate Denton
- Cardiovascular Program, Department of Physiology, Monash Biomedicine Discovery Institute, Monash University, Melbourne, VIC, Australia
| | - Clive N May
- Preclinical Critical Care Unit, The Florey Institute of Neuroscience and Mental Health, The University of Melbourne, Parkville, VIC, Australia
| | - Markus P Schlaich
- Neurovascular Hypertension and Kidney Disease Laboratory, Baker Heart and Diabetes Institute, Melbourne, VIC, Australia.,Faculty of Medicine, Nursing and Health Sciences, Central Clinical School, Monash University, Melbourne, VIC, Australia.,Dobney Hypertension Centre, School of Medicine - Royal Perth Hospital Unit, University of Western Australia, Perth, WA, Australia
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Jackson KL, Marques FZ, Lim K, Davern PJ, Head GA. Circadian Differences in the Contribution of the Brain Renin-Angiotensin System in Genetically Hypertensive Mice. Front Physiol 2018; 9:231. [PMID: 29615926 PMCID: PMC5868475 DOI: 10.3389/fphys.2018.00231] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [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: 12/20/2017] [Accepted: 03/01/2018] [Indexed: 11/21/2022] Open
Abstract
Objective: Genetically hypertensive BPH/2J mice are recognized as a neurogenic model of hypertension, primarily based on sympathetic overactivity and greater neuronal activity in cardiovascular regulatory brain regions. Greater activity of the central renin angiotensin system (RAS) and reactive oxygen species (ROS) reportedly contribute to other models of hypertension. Importantly the peripheral RAS contributes to the hypertension in BPH/2J mice, predominantly during the dark period of the 24 h light cycle. The aim of the present study was to determine whether central AT1 receptor stimulation and the associated ROS signaling contribute to hypertension in BPH/2J mice in a circadian dependent manner. Methods: Blood pressure (BP) was measured in BPH/2J and normotensive BPN/3J mice (n = 7–8) via pre-implanted telemetry devices. Acute intracerebroventricular (ICV) microinjections of AT1 receptor antagonist, candesartan, and the superoxide dismutase (SOD) mimetic, tempol, were administered during the dark and light period of the 24 h light cycle via a pre-implanted ICV guide cannula. In separate mice, the BP effect of ICV infusion of the AT1 receptor antagonist losartan for 7 days was compared with subcutaneous infusion to determine the contribution of the central RAS to hypertension in BPH/2J mice. Results: Candesartan administered ICV during the dark period induced depressor responses which were 40% smaller in BPH/2J than BPN/3J mice (Pstrain < 0.05), suggesting AT1 receptor stimulation may contribute less to BP maintenance in BPH/2J mice. During the light period candesartan had minimal effect on BP in either strain. ICV tempol had comparable effects on BP between strains during the light and dark period (Pstrain > 0.08), suggesting ROS signaling is also not contributing to the hypertension in BPH/2J mice. Chronic ICV administration of losartan (22 nmol/h) had minimal effect on BPN/3J mice. By contrast in BPH/2J mice, both ICV and subcutaneously administered losartan induced similar hypotensive responses (−12.1 ± 1.8 vs. −14.7 ± 1.8 mmHg, Proute = 0.31). Conclusion: While central effects of peripheral losartan cannot be excluded, we suggest the hypotensive effect of chronic ICV losartan was likely peripherally mediated. Thus, based on both acute and chronic AT1 receptor inhibition and acute ROS inhibition, our findings suggest that greater activation of central AT1 receptors or ROS are unlikely to be mediating the hypertension in BPH/2J mice.
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Affiliation(s)
- Kristy L Jackson
- Neuropharmacology Laboratory, Baker Heart and Diabetes Research Institute, Melbourne, VIC, Australia
| | - Francine Z Marques
- Department of Pharmacology, Monash University, Victoria, VIC, Australia.,Heart Failure Research Group, Baker Heart and Diabetes Research Institute, Melbourne, VIC, Australia
| | - Kyungjoon Lim
- Neuropharmacology Laboratory, Baker Heart and Diabetes Research Institute, Melbourne, VIC, Australia.,Department of Physiology, Anatomy and Microbiology, Latrobe University, Bundoora, VIC, Australia
| | - Pamela J Davern
- Neuropharmacology Laboratory, Baker Heart and Diabetes Research Institute, Melbourne, VIC, Australia
| | - Geoffrey A Head
- Neuropharmacology Laboratory, Baker Heart and Diabetes Research Institute, Melbourne, VIC, Australia.,Department of Pharmacology, Monash University, Victoria, VIC, Australia
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Khan SI, Andrews KL, Jackson KL, Memon B, Jefferis A, Lee MKS, Diep H, Wei Z, Drummond GR, Head GA, Jennings GL, Murphy AJ, Vinh A, Sampson AK, Chin‐Dusting JPF. Y‐chromosome lineage determines cardiovascular organ T‐cell infiltration in the stroke‐prone spontaneously hypertensive rat. FASEB J 2018; 32:2747-2756. [DOI: 10.1096/fj.201700933rr] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [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)
- Shanzana I. Khan
- Department of Pharmacology Biomedicine Discovery Institute Monash University Clayton Victoria Australia
- Department of Medicine Monash University Melbourne Victoria Australia
- Baker Heart and Diabetes Institute Melbourne Victoria Australia
| | - Karen L. Andrews
- Department of Pharmacology Biomedicine Discovery Institute Monash University Clayton Victoria Australia
- Baker Heart and Diabetes Institute Melbourne Victoria Australia
| | | | - Basimah Memon
- Baker Heart and Diabetes Institute Melbourne Victoria Australia
| | - Ann‐Maree Jefferis
- Department of Pharmacology Biomedicine Discovery Institute Monash University Clayton Victoria Australia
- Baker Heart and Diabetes Institute Melbourne Victoria Australia
| | - Man K. S. Lee
- Baker Heart and Diabetes Institute Melbourne Victoria Australia
| | - Henry Diep
- Department of Pharmacology Biomedicine Discovery Institute Monash University Clayton Victoria Australia
| | - Zihui Wei
- Department of Pharmacology Biomedicine Discovery Institute Monash University Clayton Victoria Australia
| | - Grant R. Drummond
- Department of Physiology Anatomy and Microbiology La Trobe University Bundoora Victoria Australia
| | | | - Garry L. Jennings
- Baker Heart and Diabetes Institute Melbourne Victoria Australia
- Sydney Medical School University of Sydney Camperdown New South Wales Australia
| | | | - Antony Vinh
- Department of Physiology Anatomy and Microbiology La Trobe University Bundoora Victoria Australia
| | | | - Jaye P. F. Chin‐Dusting
- Department of Pharmacology Biomedicine Discovery Institute Monash University Clayton Victoria Australia
- Department of Medicine Monash University Melbourne Victoria Australia
- Baker Heart and Diabetes Institute Melbourne Victoria Australia
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40
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Lambert EA, Phillips S, Belski R, Tursunalieva A, Eikelis N, Sari CI, Dixon JB, Straznicky N, Grima M, Head GA, Schlaich M, Lambert GW. Endothelial Function in Healthy Young Individuals Is Associated with Dietary Consumption of Saturated Fat. Front Physiol 2017; 8:876. [PMID: 29170641 PMCID: PMC5684178 DOI: 10.3389/fphys.2017.00876] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [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: 09/08/2017] [Accepted: 10/18/2017] [Indexed: 11/24/2022] Open
Abstract
Background: A diet rich in fat, in particular saturated fat (SF), may be linked to cardiovascular disease development, possibly due to a detrimental effect of fat on endothelial function (EF). Objective: We aimed to determine whether the habitual SF intake [as a ratio to total fat (the sum of saturated, polyunsaturated, and monounsaturated fat)] might influence endothelial function in young, overweight but otherwise healthy adults. Design: Sixty-nine young adults (49 males, mean age: 23 ± 1 years, mean BMI: 29.1 ± 0.8 kg/m2) were classified into three tertiles according to their habitual SF intake consumption (low SF: <39%, medium SF 39.1–43.7%, and high SF: >43.7% of total fat). Endothelial function was assessed using digital amplitude tonometry. Results: The three groups of individuals were comparable for total energy intake and calories from: fat, protein, and carbohydrates. There was no difference in anthropometric and hemodynamic variables among the groups. Those in the high SF group presented with impaired endothelial function [reactive hyperemia index (RHI): high SF: 1.60 ± 0.08 compared to 2.23 ± 0.16 in the medium SF and 2.12 ± 0.14 in the low SF group, P < 0.01]. Regression analysis, including gender, age, ethnicity, body mass index indicated that the ratio of SF to total fat was an independent predictor of the RHI (P < 0.05). Conclusion: The habitual consumption of a diet high in SF in relation to polyunsaturated and monounsaturated fat was strongly associated with impaired endothelial function in young overweight adults, potentially contributing to increased risk of developing cardiovascular disease.
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Affiliation(s)
- Elisabeth A Lambert
- Faculty of Health, Arts and Design, Iverson Health Innovation Research Institute, Swinburne University of Technology, Hawthorn, VIC, Australia.,Human Neurotransmitters Laboratory, Baker Heart and Diabetes Institute, Melbourne, VIC, Australia
| | - Sarah Phillips
- Faculty of Health, Arts and Design, Iverson Health Innovation Research Institute, Swinburne University of Technology, Hawthorn, VIC, Australia.,Human Neurotransmitters Laboratory, Baker Heart and Diabetes Institute, Melbourne, VIC, Australia
| | - Regina Belski
- Department of Health Professions, School of Health Science, Swinburne University of Technology, Hawthorn, VIC, Australia
| | - Ainura Tursunalieva
- Department of Statistics Data Science and Epidemiology, School of Health Science, Swinburne University of Technology, Hawthorn, VIC, Australia
| | - Nina Eikelis
- Faculty of Health, Arts and Design, Iverson Health Innovation Research Institute, Swinburne University of Technology, Hawthorn, VIC, Australia.,Human Neurotransmitters Laboratory, Baker Heart and Diabetes Institute, Melbourne, VIC, Australia
| | - Carolina I Sari
- Faculty of Health, Arts and Design, Iverson Health Innovation Research Institute, Swinburne University of Technology, Hawthorn, VIC, Australia
| | - John B Dixon
- Faculty of Health, Arts and Design, Iverson Health Innovation Research Institute, Swinburne University of Technology, Hawthorn, VIC, Australia.,Human Neurotransmitters Laboratory, Baker Heart and Diabetes Institute, Melbourne, VIC, Australia.,Clinical Obesity Research Laboratory, Baker Heart and Diabetes Institute, Melbourne, VIC, Australia.,Department of General Practice, Monash University, Clayton, VIC, Australia
| | - Nora Straznicky
- Faculty of Health, Arts and Design, Iverson Health Innovation Research Institute, Swinburne University of Technology, Hawthorn, VIC, Australia
| | - Mariee Grima
- Faculty of Health, Arts and Design, Iverson Health Innovation Research Institute, Swinburne University of Technology, Hawthorn, VIC, Australia
| | - Geoffrey A Head
- Neuropharmacology Laboratory, Baker Heart and Diabetes Institute, Melbourne, VIC, Australia
| | - Markus Schlaich
- Dobney Hypertension Centre, School of Medicine-Royal Perth Hospital Unit, University of Western Australia, Perth, WA, Australia
| | - Gavin W Lambert
- Faculty of Health, Arts and Design, Iverson Health Innovation Research Institute, Swinburne University of Technology, Hawthorn, VIC, Australia.,Human Neurotransmitters Laboratory, Baker Heart and Diabetes Institute, Melbourne, VIC, Australia
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41
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Lambert EA, Sari CI, Eikelis N, Phillips SE, Grima M, Straznicky NE, Dixon JB, Esler M, Schlaich MP, Head GA, Lambert GW. Effects of Moxonidine and Low-Calorie Diet: Cardiometabolic Benefits from Combination of Both Therapies. Obesity (Silver Spring) 2017; 25:1894-1902. [PMID: 28865109 DOI: 10.1002/oby.21962] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/22/2017] [Revised: 06/28/2017] [Accepted: 07/20/2017] [Indexed: 11/10/2022]
Abstract
OBJECTIVE Because sympathetic nervous system activity plays a detrimental role in metabolic and cardiovascular health, this study compared the effects of a centrally acting sympatholytic agent, the effects of a weight loss (WL) program using a low-calorie diet, and the effects of a combination of both. METHODS Young (18-30 years) male subjects with overweight (BMI > 25 kg/m2 ) were allocated to a WL program (n = 10), a moxonidine treatment course (M; n = 10, 0.4 mg/d), a combination of both (WL + M; n = 11), or to a control (C) group (n = 6) for 6 months. Muscle sympathetic nerve activity (MSNA), endothelial function, renal function (Cockcroft-Gault formula), and the metabolic profile were assessed before and after intervention. RESULTS WL occurred in the WL and WL + M groups (-7.6 ± 1.9 kg, P < 0.001 in both). MSNA and systolic blood pressure decreased similarly in the WL, M, and WL + M groups (by ∼10 bursts/min, P < 0.001, and by ∼9 mm Hg, P < 0.05). All other parameters for the WL, C, and M groups remained unchanged. In the WL + M group, decreased total cholesterol (-0.78 ± 0.23 mmol/L, P < 0.001), decreased low-density lipoprotein cholesterol (-0.49 ± 0.16 mmol/L, P < 0.01), decreased insulin (-6.5 ± 2.8 mmol/L, P < 0.05), and attenuated glomerular hyperfiltration (-19 ± 5 mL/min, P < 0.01) occurred. CONCLUSIONS The combination of moxonidine with a WL program has beneficial effects on aspects of the metabolic profile and end organ damage in young males with overweight.
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Affiliation(s)
- Elisabeth A Lambert
- Human Neurotransmitters Laboratory, Baker Heart and Diabetes Institute, Melbourne, Victoria, Australia
- Faculty of Health, Arts and Design, Iverson Health Innovation Research Institute, Swinburne University of Technology, Hawthorn, Victoria, Australia
| | - Carolina I Sari
- Human Neurotransmitters Laboratory, Baker Heart and Diabetes Institute, Melbourne, Victoria, Australia
| | - Nina Eikelis
- Human Neurotransmitters Laboratory, Baker Heart and Diabetes Institute, Melbourne, Victoria, Australia
- Faculty of Health, Arts and Design, Iverson Health Innovation Research Institute, Swinburne University of Technology, Hawthorn, Victoria, Australia
| | - Sarah E Phillips
- Human Neurotransmitters Laboratory, Baker Heart and Diabetes Institute, Melbourne, Victoria, Australia
- Faculty of Health, Arts and Design, Iverson Health Innovation Research Institute, Swinburne University of Technology, Hawthorn, Victoria, Australia
| | - Mariee Grima
- Human Neurotransmitters Laboratory, Baker Heart and Diabetes Institute, Melbourne, Victoria, Australia
| | - Nora E Straznicky
- Human Neurotransmitters Laboratory, Baker Heart and Diabetes Institute, Melbourne, Victoria, Australia
| | - John B Dixon
- Clinical Obesity Research Laboratory, Baker Heart and Diabetes Institute, Melbourne, Victoria, Australia
- Department of General Practice, Monash University, Clayton, Victoria, Australia
| | - Murray Esler
- Human Neurotransmitters Laboratory, Baker Heart and Diabetes Institute, Melbourne, Victoria, Australia
| | - Markus P Schlaich
- Dobney Hypertension Centre, School of Medicine, Royal Perth Hospital Unit, University of Western Australia, Perth, Western Australia, Australia
| | - Geoffrey A Head
- Neuropharmacology Laboratory, Baker Heart and Diabetes Institute, Melbourne, Victoria, Australia
| | - Gavin W Lambert
- Human Neurotransmitters Laboratory, Baker Heart and Diabetes Institute, Melbourne, Victoria, Australia
- Faculty of Health, Arts and Design, Iverson Health Innovation Research Institute, Swinburne University of Technology, Hawthorn, Victoria, Australia
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Lee MGY, Hemmes RA, Mynard J, Lambert E, Head GA, Cheung MMH, Konstantinov IE, Brizard CP, Lambert G, d'Udekem Y. Elevated sympathetic activity, endothelial dysfunction, and late hypertension after repair of coarctation of the aorta. Int J Cardiol 2017; 243:185-190. [PMID: 28545853 DOI: 10.1016/j.ijcard.2017.05.075] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/16/2017] [Revised: 04/16/2017] [Accepted: 05/17/2017] [Indexed: 11/30/2022]
Abstract
BACKGROUND There is a high prevalence of late hypertension after coarctation repair. The relative contribution of elevated sympathetic tone and endothelial dysfunction to its development is unknown. This study aims to investigate the neural profile of coarctation patients including muscle sympathetic nerve activity testing to directly measure sympathetic nervous activity. METHODS Twenty-three patients aged ≥18years with a coarctation repair underwent measurements of clinic and 24-h blood pressures, muscle sympathetic nerve activity, sympathetic and cardiac baroreflex functions, digital endothelial function, and ambulatory arterial stiffness index. Median age at repair was 1.2months (interquartile range: 0-9months). Patients were compared to 17 healthy matched controls. RESULTS After 26±5years, 6% (1/18) and 44% (8/18) suffered clinic hypertension and prehypertension, respectively. On 24-h blood pressure monitoring, 15% (3/20) and 20% (4/20) had hypertension and prehypertension, respectively. Coarctation patients had elevated muscle sympathetic nerve activity compared with controls (49.6±24.9 vs. 29.9±14.0 bursts/100 heartbeats, p=0.02), dampened sympathetic baroreflex function (-2.2±2.1 vs. -7.0±5.6 bursts/100heartbeats·mm·Hg-1, p=0.007), normal cardiac baroreflex function (41.9±30.4 vs. 35.7±21.1ms·mm·Hg-1, p=0.6), endothelial dysfunction (pulse amplitude tonometry ratio: 0.39±0.32 vs. 0.81±0.50, p=0.004), and increased ambulatory arterial stiffness index (0.46±0.15 vs. 0.29±0.17, p=0.008). CONCLUSION After coarctation repair patients have increased muscle sympathetic nerve activity, dampened sympathetic baroreflex response, endothelial dysfunction, and increased ambulatory arterial stiffness index, all of which may contribute to the development of late hypertension.
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Affiliation(s)
- Melissa G Y Lee
- Department of Cardiac Surgery, The Royal Children's Hospital, Melbourne, Australia; Department of Paediatrics, University of Melbourne, Melbourne, Australia; Heart Research, Clinical Sciences, Murdoch Childrens Research Institute, Melbourne, Australia.
| | - Robyn A Hemmes
- Human Neurotransmitters Laboratory, Baker IDI Heart and Diabetes Institute, Melbourne, Australia.
| | - Jonathan Mynard
- Heart Research, Clinical Sciences, Murdoch Childrens Research Institute, Melbourne, Australia.
| | - Elisabeth Lambert
- Human Neurotransmitters Laboratory, Baker IDI Heart and Diabetes Institute, Melbourne, Australia; Iverson Health Innovation Research Institute, Swinburne University of Technology, Melbourne, Australia.
| | - Geoffrey A Head
- Neuropharmacology Laboratory, Baker IDI Heart and Diabetes Institute, Melbourne, Australia.
| | - Michael M H Cheung
- Department of Paediatrics, University of Melbourne, Melbourne, Australia; Heart Research, Clinical Sciences, Murdoch Childrens Research Institute, Melbourne, Australia; Department of Cardiology, The Royal Children's Hospital, Melbourne, Australia.
| | - Igor E Konstantinov
- Department of Cardiac Surgery, The Royal Children's Hospital, Melbourne, Australia; Department of Paediatrics, University of Melbourne, Melbourne, Australia; Heart Research, Clinical Sciences, Murdoch Childrens Research Institute, Melbourne, Australia.
| | - Christian P Brizard
- Department of Cardiac Surgery, The Royal Children's Hospital, Melbourne, Australia; Department of Paediatrics, University of Melbourne, Melbourne, Australia; Heart Research, Clinical Sciences, Murdoch Childrens Research Institute, Melbourne, Australia.
| | - Gavin Lambert
- Human Neurotransmitters Laboratory, Baker IDI Heart and Diabetes Institute, Melbourne, Australia; Iverson Health Innovation Research Institute, Swinburne University of Technology, Melbourne, Australia.
| | - Yves d'Udekem
- Department of Cardiac Surgery, The Royal Children's Hospital, Melbourne, Australia; Department of Paediatrics, University of Melbourne, Melbourne, Australia; Heart Research, Clinical Sciences, Murdoch Childrens Research Institute, Melbourne, Australia.
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Hart EC, Head GA, Carter JR, Wallin BG, May CN, Hamza SM, Hall JE, Charkoudian N, Osborn JW. Recording sympathetic nerve activity in conscious humans and other mammals: guidelines and the road to standardization. Am J Physiol Heart Circ Physiol 2017; 312:H1031-H1051. [PMID: 28364017 DOI: 10.1152/ajpheart.00703.2016] [Citation(s) in RCA: 103] [Impact Index Per Article: 14.7] [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: 10/26/2016] [Revised: 03/06/2017] [Accepted: 03/06/2017] [Indexed: 01/03/2023]
Abstract
Over the past several decades, studies of the sympathetic nervous system in humans, sheep, rabbits, rats, and mice have substantially increased mechanistic understanding of cardiovascular function and dysfunction. Recently, interest in sympathetic neural mechanisms contributing to blood pressure control has grown, in part because of the development of devices or surgical procedures that treat hypertension by manipulating sympathetic outflow. Studies in animal models have provided important insights into physiological and pathophysiological mechanisms that are not accessible in human studies. Across species and among laboratories, various approaches have been developed to record, quantify, analyze, and interpret sympathetic nerve activity (SNA). In general, SNA demonstrates "bursting" behavior, where groups of action potentials are synchronized and linked to the cardiac cycle via the arterial baroreflex. In humans, it is common to quantify SNA as bursts per minute or bursts per 100 heart beats. This type of quantification can be done in other species but is only commonly reported in sheep, which have heart rates similar to humans. In rabbits, rats, and mice, SNA is often recorded relative to a maximal level elicited in the laboratory to control for differences in electrode position among animals or on different study days. SNA in humans can also be presented as total activity, where normalization to the largest burst is a common approach. The goal of the present paper is to put together a summary of "best practices" in several of the most common experimental models and to discuss opportunities and challenges relative to the optimal measurement of SNA across species.Listen to this article's corresponding podcast at https://ajpheart.podbean.com/e/guidelines-for-measuring-sympathetic-nerve-activity/.
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Affiliation(s)
- Emma C Hart
- School of Physiology, Pharmacology and Neuroscience, University of Bristol, Bristol, United Kingdom;
| | - Geoffrey A Head
- Baker IDI Heart and Diabetes Institute, Melbourne, Victoria, Australia
| | | | | | - Clive N May
- Florey Institute of Neuroscience and Mental Health, University of Melbourne, Parkville, Victoria, Australia
| | | | - John E Hall
- Department of Physiology and Biophysics, Mississippi Center for Obesity Research, University of Mississippi Medical Center, Jackson, Mississippi
| | - Nisha Charkoudian
- United States Army Research Institute of Environmental Medicine, Natick, Massachusetts; and
| | - John W Osborn
- Department of Integrative Biology and Physiology, University of Minnesota Medical School, Minneapolis, Minnesota
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Lim K, Sata Y, Jackson KL, Burke SL, Head GA. Acute Effect of Central Administration of Urotensin II on Baroreflex and Blood Pressure in Conscious Normotensive Rabbits. Front Physiol 2017; 8:110. [PMID: 28280470 PMCID: PMC5322237 DOI: 10.3389/fphys.2017.00110] [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] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2017] [Accepted: 02/09/2017] [Indexed: 12/03/2022] Open
Abstract
In the present study, we examined the effects of central administration of Urotensin II on blood pressure, heart rate, and baroreceptor heart rate reflexes in conscious normotensive rabbits. Preliminary operations were undertaken to implant a balloon cuff on the inferior vena cava for baroreflex assessments and to implant cannula into the lateral and fourth ventricle. After 2 weeks of recovery cumulative dose response curves to Urotensin II (10, 100 ng, 1, 10, and 100 μg) given into the ventricles, or Ringer's solution as a vehicle were performed on separate days. Injections were given each hour and baroreflex assessments were made 30 min after each administration. Analysis of the dose response curves to Urotensin II compared to vehicle administered into the lateral or fourth ventricle, indicated little change to blood pressure or heart rate. Analysis of the time course to the highest dose over a 30 min period revealed a small (−5 mmHg) depressor response maximal at 10 min when injected into the fourth ventricle but no effect when injected into the lateral ventricle. Baroreflex assessments made at each dose showed that there was no change in baroreflex sensitivity but that an increase in the upper plateau was observed when Urotensin was injected into the lateral ventricle and a tendency for a reduced lower heart rate plateau was observed after fourth ventricle administration. Clonidine administration in the fourth ventricle decreased blood pressure and heart rate, thus confirming catheter patency. In conclusion, our findings suggest that Urotensin II in the forebrain and brainstem may play a role in modulating cardiac sympathetic and vagal baroreflexes but only during large acute changes in blood pressure.
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Affiliation(s)
- Kyungjoon Lim
- Department of Neuropharmacology, Baker IDI Heart and Diabetes Research InstituteMelbourne, VIC, Australia; Department of Physiology, Monash UniversityClayton, VIC, Australia
| | - Yusuke Sata
- Department of Neuropharmacology, Baker IDI Heart and Diabetes Research InstituteMelbourne, VIC, Australia; Faculty of Medicine, Nursing and Health Science, Monash UniversityClayton, VIC, Australia
| | - Kristy L Jackson
- Department of Neuropharmacology, Baker IDI Heart and Diabetes Research Institute Melbourne, VIC, Australia
| | - Sandra L Burke
- Department of Neuropharmacology, Baker IDI Heart and Diabetes Research Institute Melbourne, VIC, Australia
| | - Geoffrey A Head
- Department of Neuropharmacology, Baker IDI Heart and Diabetes Research InstituteMelbourne, VIC, Australia; Department of Pharmacology, Monash UniversityClayton, VIC, Australia
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Singh RR, Sajeesh V, Booth LC, McArdle Z, May CN, Head GA, Moritz KM, Schlaich MP, Denton KM. Catheter-Based Renal Denervation Exacerbates Blood Pressure Fall During Hemorrhage. J Am Coll Cardiol 2017; 69:951-964. [DOI: 10.1016/j.jacc.2016.12.014] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/16/2016] [Revised: 12/06/2016] [Accepted: 12/13/2016] [Indexed: 10/20/2022]
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Marques FZ, Eikelis N, Bayles RG, Lambert EA, Straznicky NE, Hering D, Esler MD, Head GA, Barton DA, Schlaich MP, Lambert GW. A polymorphism in the norepinephrine transporter gene is associated with affective and cardiovascular disease through a microRNA mechanism. Mol Psychiatry 2017; 22:134-141. [PMID: 27046647 DOI: 10.1038/mp.2016.40] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/08/2015] [Revised: 02/11/2016] [Accepted: 02/17/2016] [Indexed: 12/31/2022]
Abstract
Norepinephrine released from sympathetic nerves is removed from the neuroeffector junction via the action of the norepinephrine transporter (NET). NET impairment is evident in several clinically important conditions including major depressive disorder (MDD), panic disorder (PD), essential hypertension and the postural orthostatic tachycardia syndrome (POTS). We aimed to determine whether a single nucleotide polymorphism (SNP) in the 3' untranslated region (UTR) of the NET gene is associated with NET impairment and to elucidate the mechanisms involved. The analyses were carried out in two cohorts of European ancestry, which included healthy controls and MDD, PD, hypertensive and POTS patients. Compared with controls, cases had significantly higher prevalence of the T allele of rs7194256 (C/T), arterial norepinephrine, depression and anxiety scores, larger left ventricular mass index, higher systolic and diastolic blood pressures, and heart rate. Bioinformatic analysis identified that the microRNA miR-19a-3p could bind preferentially to the sequence created by the presence of the T allele. This was supported by results of luciferase assays. Compared with controls, cases had significantly lower circulating miR-19a-3p, which was associated with pathways related to blood pressure and regulation of neurotransmission. In vitro norepinephrine downregulated miR-19a-3p. In conclusion, the T allele of the rs7194256 SNP in the 3'UTR of the NET gene is more prevalent in diseases where NET impairment is evident. This might be explained by the creation of a binding site for the microRNA miR-19a-3p. A defect in NET function may potentiate the sympathetic neurochemical signal, predisposing individuals with affective diseases to increased risk of cardiovascular disease development.
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Affiliation(s)
- F Z Marques
- The Heart Failure Research Group, Baker IDI Heart and Diabetes Institute, Melbourne, VIC, Australia.,The Central Clinical School, Faculty of Medicine, Monash University, Melbourne, VIC, Australia
| | - N Eikelis
- The Human Neurotransmitters Laboratories, Baker IDI Heart and Diabetes Institute, Melbourne, VIC, Australia
| | - R G Bayles
- The Human Neurotransmitters Laboratories, Baker IDI Heart and Diabetes Institute, Melbourne, VIC, Australia
| | - E A Lambert
- The Human Neurotransmitters Laboratories, Baker IDI Heart and Diabetes Institute, Melbourne, VIC, Australia.,The Department of Physiology, Monash University, Melbourne, VIC, Australia
| | - N E Straznicky
- The Human Neurotransmitters Laboratories, Baker IDI Heart and Diabetes Institute, Melbourne, VIC, Australia
| | - D Hering
- Neurovascular Hypertension & Kidney Disease Laboratories, Baker IDI Heart and Diabetes Institute, Melbourne, VIC, Australia.,Dobney Hypertension Centre, School of Medicine and Pharmacology, University of Western Australia, Perth, WA, Australia
| | - M D Esler
- The Central Clinical School, Faculty of Medicine, Monash University, Melbourne, VIC, Australia.,The Human Neurotransmitters Laboratories, Baker IDI Heart and Diabetes Institute, Melbourne, VIC, Australia
| | - G A Head
- Neuropharmacology Laboratories, Baker IDI Heart and Diabetes Research Institute, Melbourne, VIC, Australia.,The Department of Pharmacology, Monash University, Melbourne, VIC, Australia
| | - D A Barton
- The Central Clinical School, Faculty of Medicine, Monash University, Melbourne, VIC, Australia.,The Human Neurotransmitters Laboratories, Baker IDI Heart and Diabetes Institute, Melbourne, VIC, Australia
| | - M P Schlaich
- The Central Clinical School, Faculty of Medicine, Monash University, Melbourne, VIC, Australia.,Neurovascular Hypertension & Kidney Disease Laboratories, Baker IDI Heart and Diabetes Institute, Melbourne, VIC, Australia.,Dobney Hypertension Centre, School of Medicine and Pharmacology, University of Western Australia, Perth, WA, Australia
| | - G W Lambert
- The Central Clinical School, Faculty of Medicine, Monash University, Melbourne, VIC, Australia.,The Human Neurotransmitters Laboratories, Baker IDI Heart and Diabetes Institute, Melbourne, VIC, Australia
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Parkin ML, Lim K, Burke SL, Head GA. Comparison in Conscious Rabbits of the Baroreceptor-Heart Rate Reflex Effects of Chronic Treatment with Rilmenidine, Moxonidine, and Clonidine. Front Physiol 2016; 7:522. [PMID: 27895591 PMCID: PMC5108798 DOI: 10.3389/fphys.2016.00522] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [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: 09/01/2016] [Accepted: 10/24/2016] [Indexed: 11/13/2022] Open
Abstract
We investigated the effects of chronic subcutaneous treatment with centrally-acting antihypertensive agents moxonidine, rilmenidine, and clonidine on the baroreflex control of heart rate (HR) in conscious normotensive rabbits over 3 weeks. Infusions of phenylephrine and nitroprusside were performed at week 0 and at weeks 1 and 3 of treatment to determine mean arterial pressure (MAP)-HR baroreflex relationships. A second curve was performed after intravenous methscopolamine to determine the sympathetic baroreflex relationship. The vagal component of the reflex was determined by subtracting the sympathetic curve from the intact curve. Clonidine and moxonidine (both 1 mg/kg/day), and rilmenidine (5 mg/kg/day), reduced MAP by 13 ± 3, 15 ± 2, and 13 ± 2 mmHg, respectively, but had no effect on HR over the 3-week treatment period. Whilst all three antihypertensive agents shifted baroreflex curves to the left, parallel to the degree of hypotension, moxonidine and rilmenidine decreased the vagal contribution to the baroreflex by decreasing the HR range of the reflex but moxonidine also increased sympathetic baroreflex range and sensitivity. By contrast clonidine had little chronic effect on the cardiac baroreflex. The present study shows that second generation agents moxonidine and rilmenidine but not first generation agent clonidine chronically shift the balance of baroreflex control of HR toward greater sympathetic and lesser vagal influences. These changes if translated to hypertensive subjects, may not be particularly helpful in view of the already reduced vagal contribution in hypertension.
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Affiliation(s)
- Monique L Parkin
- Neuropharmacology Laboratory, Baker IDI Heart and Diabetes Institute Melbourne, VIC, Australia
| | - Kyungjoon Lim
- Neuropharmacology Laboratory, Baker IDI Heart and Diabetes Institute Melbourne, VIC, Australia
| | - Sandra L Burke
- Neuropharmacology Laboratory, Baker IDI Heart and Diabetes Institute Melbourne, VIC, Australia
| | - Geoffrey A Head
- Neuropharmacology Laboratory, Baker IDI Heart and Diabetes Institute Melbourne, VIC, Australia
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Veloudi P, Blizzard CL, Head GA, Abhayaratna WP, Stowasser M, Sharman JE. Blood Pressure Variability and Prediction of Target Organ Damage in Patients With Uncomplicated Hypertension. Am J Hypertens 2016; 29:1046-54. [PMID: 27076601 DOI: 10.1093/ajh/hpw037] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2016] [Accepted: 03/23/2016] [Indexed: 02/03/2023] Open
Abstract
BACKGROUND The average of multiple blood pressure (BP) readings (mean BP) independently predicts target organ damage (TOD). Observational studies have also shown an independent relationship between BP variability (BPV) and TOD, but there is limited longitudinal data. This study aimed to determine the effects of changes in mean BP levels compared with BPV on left ventricular mass index (LVMI) and aortic pulse wave velocity (aPWV). METHODS Mean BP levels (research-protocol clinic BP (clinic BP), 24-hour ambulatory BP, and 7-day home BP) and BPV were assessed in 286 patients with uncomplicated hypertension (mean age 64±8 SD years, 53% women) over 12 months. Reading-to-reading BPV (from 24-hour ambulatory BP) and day-to-day BPV (from 7-day home BP) were assessed at baseline and 12 months, and visit-to-visit BPV (clinic BP) was assessed from 5 visits over 12 months. LVMI was measured by 3D echocardiography and aPWV with applanation tonometry. RESULTS The strongest predictors of the changes in LVMI (ΔLVMI) were the changes in mean 24-hour systolic BPs (SBPs) (P < 0.02). Similarly, the strongest predictors of the changes in aPWV (ΔaPWV) were the changes in mean 24-hour ambulatory SBPs (P < 0.01) and the changes in mean clinic SBP (P < 0.001). However, none of the changes in BPV were independently associated with ΔLVMI or ΔaPWV (P > 0.05 for all). CONCLUSIONS Changes in mean BP levels, but not BPV, were most relevant to changes in TOD in patients with uncomplicated hypertension. Thus, from this point of view, BPV appears to have limited clinical utility in this patient population.
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Affiliation(s)
- Panagiota Veloudi
- Menzies Institute for Medical Research, University of Tasmania, Hobart, Tasmania, Australia
| | - Christopher L Blizzard
- Menzies Institute for Medical Research, University of Tasmania, Hobart, Tasmania, Australia
| | - Geoffrey A Head
- Baker IDI Heart and Diabetes Institute, Melbourne, Victoria, Australia
| | - Walter P Abhayaratna
- Canberra Hospital, College of Medicine, Biology and Environment, Australian National University, Garran, Canberra, Australia
| | - Michael Stowasser
- Endocrine Hypertension Research Centre, School of Medicine, University of Queensland, Brisbane, Queensland, Australia
| | - James E Sharman
- Menzies Institute for Medical Research, University of Tasmania, Hobart, Tasmania, Australia;
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Lim K, Burke SL, Moretti JL, Head GA. Differential activation of renal sympathetic burst amplitude and frequency during hypoxia, stress and baroreflexes with chronic angiotensin treatment. Exp Physiol 2016; 100:1132-44. [PMID: 26442604 DOI: 10.1113/ep085312] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2015] [Accepted: 08/20/2015] [Indexed: 11/08/2022]
Abstract
NEW FINDINGS What is the central question of this study? Is the elevated tonic renal nerve activity induced by chronic angiotensin administration mediated by recruitment or increased firing frequency and does this occur via stress, chemoreflex or baroreflex pathways? What is the main finding and its importance? Long-term angiotensin treatment in rabbits elevates renal sympathetic nerve activity by recruitment of previously silent fibres. This was similar to the effect of chemoreflex stimulation, but not to stress or baroreceptor activation, suggesting that presympathetic pathways activated by angiotensin may be common to those activated by chemoreceptors. Modulation of sympathetic nerve activity involves control by the CNS of the amplitude of neural discharges, reflecting recruitment of neurons and their firing frequency. We tested whether elevated tonic renal sympathetic nerve activity (RSNA) induced by chronic angiotensin administration is mediated by recruitment or increased firing frequency and whether this is characteristic of the pattern observed with activation of stress, chemoreflex or baroreflex pathways. Conscious rabbits treated with angiotensin II for 12 weeks to increase blood pressure by 10-30% were subjected to stress (air jet), hypoxia (10% O2 + 3% CO2) and drug-induced changes in blood pressure to produce baroreflexes. Total RSNA and RSNA burst amplitude were scaled to 100 normalized units (n.u.) by the maximal response to smoke. After 12 weeks of treatment, blood pressure was 17% higher than baseline 68 ± 1 mmHg (P = 0.02). Compared with sham treatment, total RSNA and burst amplitude were +82% (P < 0.001) and 39% (P = 0.04) greater, but burst frequency was similar. Total RSNA increased during hypoxia (+38% from 4.9 ± 0.7 n.u.), owing to greater amplitude, but not frequency. Air-jet stress increased total RSNA (+44% from 4.3 ± 0.5 n.u.) and burst frequency (+21% from 5.4 ± 0.7 bursts s(-1) ), but not amplitude. Angiotensin enhanced total RSNA responses to both air jet (+33%) and hypoxia (+58%), but only increased the amplitude response to air jet. The RSNA baroreflexes reset to the higher blood pressure, but amplitude or frequency was not differentially altered. Chronic angiotensin treatment elevated RSNA by recruitment of neurons, which is similar to chemoreflex stimulation, but not to stress or baroreceptor activation, suggesting that presympathetic pathways activated by angiotensin may be common to those activated by chemoreceptors.
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Affiliation(s)
- Kyungjoon Lim
- Neuropharmacology Laboratory, Baker IDI Heart and Diabetes Institute, Melbourne, Victoria, Australia
| | - Sandra L Burke
- Neuropharmacology Laboratory, Baker IDI Heart and Diabetes Institute, Melbourne, Victoria, Australia
| | - John-Luis Moretti
- Neuropharmacology Laboratory, Baker IDI Heart and Diabetes Institute, Melbourne, Victoria, Australia
| | - Geoffrey A Head
- Neuropharmacology Laboratory, Baker IDI Heart and Diabetes Institute, Melbourne, Victoria, Australia.,Department of Pharmacology, Monash University, Clayton, Victoria, Australia
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Lim K, Barzel B, Burke SL, Armitage JA, Head GA. Origin of Aberrant Blood Pressure and Sympathetic Regulation in Diet-Induced Obesity. Hypertension 2016; 68:491-500. [DOI: 10.1161/hypertensionaha.116.07461] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2016] [Accepted: 05/06/2016] [Indexed: 11/16/2022]
Abstract
High fat diet (HFD)–induced hypertension in rabbits is neurogenic and caused by the central action of leptin, which is thought to be dependent on activation of α-melanocortin–stimulating hormone (α-MSH) and neuropeptide Y–positive neurons projecting to the dorsomedial hypothalamus (DMH) and ventromedial hypothalamus (VMH). However, leptin may act directly in these nuclei. Here, we assessed the contribution of leptin, α-MSH, and neuropeptide Y signaling in the DMH and VMH to diet-induced hypertension. Male New Zealand white rabbits were instrumented with a cannula for drug injections into the DMH or VMH and a renal sympathetic nerve activity (RSNA) electrode. After 3 weeks of an HFD (13.3% fat; n=19), rabbits exhibited higher RSNA, mean arterial pressure (MAP), and heart rate compared with control diet–fed animals (4.2% fat; n=15). Intra-VMH injections of a leptin receptor antagonist or SHU9119, a melanocortin 3/4 receptor antagonist, decreased MAP, heart rate, and RSNA compared with vehicle in HFD rabbits (
P
<0.05) but not in control diet–fed animals. By contrast, α-MSH or neuropeptide Y injected into the VMH had no effect on MAP but produced sympathoexcitation in HFD rabbits (
P
<0.05) but not in control diet–fed rabbits. The effects of the leptin antagonist, α-MSH, or neuropeptide Y injections into the DMH on MAP or RSNA of HFD rabbits were not different from those after vehicle injection. α-MSH into the DMH of control diet–fed animals did increase MAP, heart rate, and RSNA. We conclude that the VMH is the likely origin of leptin-mediated sympathoexcitation and α-MSH hypersensitivity that contribute to obesity-related hypertension.
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Affiliation(s)
- Kyungjoon Lim
- From the Baker IDI Heart and Diabetes Institute, Melbourne, Victoria, Australia (K.L., B.B., S.L.B., J.A.A., G.A.H.); Department of Anatomy and Developmental Biology, Monash University, Clayton, Victoria, Australia (B.B., J.A.A.); School of Medicine (Optometry), Deakin University, Waurn Ponds, Victoria, Australia (J.A.A.); and Department of Pharmacology, Monash University, Clayton, Victoria, Australia (G.A.H.)
| | - Benjamin Barzel
- From the Baker IDI Heart and Diabetes Institute, Melbourne, Victoria, Australia (K.L., B.B., S.L.B., J.A.A., G.A.H.); Department of Anatomy and Developmental Biology, Monash University, Clayton, Victoria, Australia (B.B., J.A.A.); School of Medicine (Optometry), Deakin University, Waurn Ponds, Victoria, Australia (J.A.A.); and Department of Pharmacology, Monash University, Clayton, Victoria, Australia (G.A.H.)
| | - Sandra L. Burke
- From the Baker IDI Heart and Diabetes Institute, Melbourne, Victoria, Australia (K.L., B.B., S.L.B., J.A.A., G.A.H.); Department of Anatomy and Developmental Biology, Monash University, Clayton, Victoria, Australia (B.B., J.A.A.); School of Medicine (Optometry), Deakin University, Waurn Ponds, Victoria, Australia (J.A.A.); and Department of Pharmacology, Monash University, Clayton, Victoria, Australia (G.A.H.)
| | - James A. Armitage
- From the Baker IDI Heart and Diabetes Institute, Melbourne, Victoria, Australia (K.L., B.B., S.L.B., J.A.A., G.A.H.); Department of Anatomy and Developmental Biology, Monash University, Clayton, Victoria, Australia (B.B., J.A.A.); School of Medicine (Optometry), Deakin University, Waurn Ponds, Victoria, Australia (J.A.A.); and Department of Pharmacology, Monash University, Clayton, Victoria, Australia (G.A.H.)
| | - Geoffrey A. Head
- From the Baker IDI Heart and Diabetes Institute, Melbourne, Victoria, Australia (K.L., B.B., S.L.B., J.A.A., G.A.H.); Department of Anatomy and Developmental Biology, Monash University, Clayton, Victoria, Australia (B.B., J.A.A.); School of Medicine (Optometry), Deakin University, Waurn Ponds, Victoria, Australia (J.A.A.); and Department of Pharmacology, Monash University, Clayton, Victoria, Australia (G.A.H.)
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