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Zarate SM, Kirabo A, Hinton AO, Santisteban MM. Neuroimmunology of Cardiovascular Disease. Curr Hypertens Rep 2024; 26:339-347. [PMID: 38613621 PMCID: PMC11199253 DOI: 10.1007/s11906-024-01301-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/15/2024] [Indexed: 04/15/2024]
Abstract
PURPOSE OF REVIEW Cardiovascular disease (CVD) is a leading cause of death and chronic disability worldwide. Yet, despite extensive intervention strategies the number of persons affected by CVD continues to rise. Thus, there is great interest in unveiling novel mechanisms that may lead to new treatments. Considering this dilemma, recent focus has turned to the neuroimmune mechanisms involved in CVD pathology leading to a deeper understanding of the brain's involvement in disease pathology. This review provides an overview of new and salient findings regarding the neuroimmune mechanisms that contribute to CVD. RECENT FINDINGS The brain contains neuroimmune niches comprised of glia in the parenchyma and immune cells at the brain's borders, and there is strong evidence that these neuroimmune niches are important in both health and disease. Mechanistic studies suggest that the activation of glia and immune cells in these niches modulates CVD progression in hypertension and heart failure and contributes to the inevitable end-organ damage to the brain. This review provides evidence supporting the role of neuroimmune niches in CVD progression. However, additional research is needed to understand the effects of prolonged neuroimmune activation on brain function.
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Affiliation(s)
- Sara M Zarate
- Division of Clinical Pharmacology, Department of Medicine, Vanderbilt University Medical Center, Nashville, USA
| | - Annet Kirabo
- Division of Clinical Pharmacology, Department of Medicine, Vanderbilt University Medical Center, Nashville, USA
- Department of Molecular Physiology and Biophysics, Vanderbilt University, Nashville, USA
- Vanderbilt Center for Immunobiology, Nashville, USA
- Vanderbilt Institute for Infection, Immunology, and Inflammation, Nashville, USA
- Vanderbilt Institute for Global Health, Nashville, USA
| | - Antentor O Hinton
- Department of Molecular Physiology and Biophysics, Vanderbilt University, Nashville, USA
| | - Monica M Santisteban
- Division of Clinical Pharmacology, Department of Medicine, Vanderbilt University Medical Center, Nashville, USA.
- Vanderbilt Institute for Infection, Immunology, and Inflammation, Nashville, USA.
- Vanderbilt Memory and Alzheimer's Center, Vanderbilt University Medical Center, Nashville, USA.
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Wu XL, Zhang L, Zhang J, Sun J, Li YY, Yang KZ, Liu Y, Gao XY, Liu QG. Acupuncture modulation of the ACE/Ang II/AT1R and ACE2/Ang(1-7)/MasR pathways in the rostral ventrolateral medulla reduces sympathetic output and prevents cardiac injury caused by SHR hypertension. Neuroreport 2024:00001756-990000000-00262. [PMID: 38973500 DOI: 10.1097/wnr.0000000000002073] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/09/2024]
Abstract
Acupuncture can reduce blood pressure, heart rate (HR), and ameliorate cardiac damage by modulating the excitability of the sympathetic nervous system, but the exact mechanism of this effect remains unclear. This study investigated the potential mechanisms of acupuncture in the treatment of cardiac damage in hypertension. Spontaneously hypertensive rats (SHR) were used as the hypertension model with Wistar-Kyoto rats as the control. Manual acupuncture, electroacupuncture, and metoprolol were used as interventions. Systolic and diastolic blood pressure (SBP, DBP) plus HR were monitored with cardiac structure determined using Masson staining. Angiotensin II (Ang II) and norepinephrine in myocardium were detected with ELISA as was Ang(1-7) and gamma aminobutyric acid (GABA) in the rostral ventrolateral medulla (RVLM). Expression of mRNA for collagen type I (Col-I), Col-III, actin α1 (ACTA1), and thrombospondin 4 (THBS4) in myocardium was detected using real-time PCR. Expression of angiotensin converting enzyme (ACE), Ang II, angiotensin II type 1 receptor (AT1R), ACE2, and Mas receptor (MasR) proteins in RVLM was monitored using western blot. After manual acupuncture and electroacupuncture treatment, SHRs showed decreased SBP, DBP and HR, reduced myocardial damage. There was decreased expression of the ACE/Ang II/AT1R axis, and increased expression of the ACE2/Ang(1-7)/MasR axis within the RVLM. GABA levels were increased within the RVLM and norepinephrine levels were decreased in myocardial tissue. Metoprolol was more effective than either manual acupuncture or electroacupuncture. Acupuncture directed against hypertensive cardiac damage may be associated with regulation of ACE/Ang II/AT1R and the ACE2/Ang(1-7)/MasR pathway within the RLVM to reduce cardiac sympathetic excitability.
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Affiliation(s)
- Xiao-Li Wu
- School of Acupuncture-Moxibustion and Tuina, Beijing University of Chinese Medicine, Beijing
| | - Lin Zhang
- School of Acupuncture-Moxibustion and Tuina, Beijing University of Chinese Medicine, Beijing
| | - Jing Zhang
- School of Acupuncture-Moxibustion and Tuina, Beijing University of Chinese Medicine, Beijing
| | - Jiao Sun
- School of Acupuncture-Moxibustion and Tuina, Beijing University of Chinese Medicine, Beijing
| | - Yin-Yin Li
- School of Acupuncture-Moxibustion and Tuina, Beijing University of Chinese Medicine, Beijing
| | - Ke-Zhen Yang
- Department of Rehabilitation Medicine, Sir Run Run Shaw Hospital, Zhejiang University School of Medicine, Hangzhou
| | - Yu Liu
- Dongzhimen Hospital Affiliated to Beijing University of Chinese Medicine, Beijing, China
| | - Xin-Yu Gao
- School of Acupuncture-Moxibustion and Tuina, Beijing University of Chinese Medicine, Beijing
| | - Qing-Guo Liu
- School of Acupuncture-Moxibustion and Tuina, Beijing University of Chinese Medicine, Beijing
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Wei W, Ma D, Li L, Zhang L. Cognitive impairment in cerebral small vessel disease induced by hypertension. Neural Regen Res 2024; 19:1454-1462. [PMID: 38051887 PMCID: PMC10883517 DOI: 10.4103/1673-5374.385841] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2023] [Accepted: 08/22/2023] [Indexed: 12/07/2023] Open
Abstract
ABSTRACT Hypertension is a primary risk factor for the progression of cognitive impairment caused by cerebral small vessel disease, the most common cerebrovascular disease. However, the causal relationship between hypertension and cerebral small vessel disease remains unclear. Hypertension has substantial negative impacts on brain health and is recognized as a risk factor for cerebrovascular disease. Chronic hypertension and lifestyle factors are associated with risks for stroke and dementia, and cerebral small vessel disease can cause dementia and stroke. Hypertension is the main driver of cerebral small vessel disease, which changes the structure and function of cerebral vessels via various mechanisms and leads to lacunar infarction, leukoaraiosis, white matter lesions, and intracerebral hemorrhage, ultimately resulting in cognitive decline and demonstrating that the brain is the target organ of hypertension. This review updates our understanding of the pathogenesis of hypertension-induced cerebral small vessel disease and the resulting changes in brain structure and function and declines in cognitive ability. We also discuss drugs to treat cerebral small vessel disease and cognitive impairment.
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Affiliation(s)
- Weipeng Wei
- Department of Pharmacy, Xuanwu Hospital of Capital Medical University, Beijing, China
- Beijing Geriatric Medical Research Center; Beijing Engineering Research Center for Nervous System Drugs; National Center for Neurological Disorders; National Clinical Research Center for Geriatric Diseases, Beijing, China
| | - Denglei Ma
- Department of Pharmacy, Xuanwu Hospital of Capital Medical University, Beijing, China
- Beijing Geriatric Medical Research Center; Beijing Engineering Research Center for Nervous System Drugs; National Center for Neurological Disorders; National Clinical Research Center for Geriatric Diseases, Beijing, China
| | - Lin Li
- Department of Pharmacy, Xuanwu Hospital of Capital Medical University, Beijing, China
- Beijing Geriatric Medical Research Center; Beijing Engineering Research Center for Nervous System Drugs; National Center for Neurological Disorders; National Clinical Research Center for Geriatric Diseases, Beijing, China
| | - Lan Zhang
- Department of Pharmacy, Xuanwu Hospital of Capital Medical University, Beijing, China
- Beijing Geriatric Medical Research Center; Beijing Engineering Research Center for Nervous System Drugs; National Center for Neurological Disorders; National Clinical Research Center for Geriatric Diseases, Beijing, China
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Dalmasso C, Ahmed NS, Ghuneim S, Cincinelli C, Leachman JR, Giani JF, Cassis L, Loria AS. Obese Male Mice Exposed to Early Life Stress Display Sympathetic Activation and Hypertension Independent of Circulating Angiotensin II. J Am Heart Assoc 2024; 13:e029511. [PMID: 38156515 PMCID: PMC10863837 DOI: 10.1161/jaha.123.029511] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/20/2023] [Accepted: 11/03/2023] [Indexed: 12/30/2023]
Abstract
BACKGROUND We have previously reported that male mice exposed to maternal separation and early weaning (MSEW), a model of early life stress, show sympathetic activation and increased blood pressure in response to a chronic high-fat diet. The goal of this study was to investigate the contribution of the renin-angiotensin-aldosterone system to the mechanism by which MSEW increases blood pressure and vasomotor sympathetic tone in obese male mice. METHODS AND RESULTS Mice were exposed to MSEW during postnatal life. Undisturbed litters served as controls. At weaning, both control and MSEW offspring were placed on a low-fat diet or a high-fat diet for 20 weeks. Angiotensin peptides in serum were similar in control and MSEW mice regardless of the diet. However, a high-fat diet induced a similar increase in angiotensinogen levels in serum, renal cortex, liver, and fat in both control and MSEW mice. No evidence of renin-angiotensin system activation was found in adipose tissue and renal cortex. After chronic treatment with enalapril (2.5 mg/kg per day, drinking water, 7 days), an angiotensin-converting enzyme inhibitor that does not cross the blood-brain barrier, induced a similar reduction in blood pressure in both groups, while the vasomotor sympathetic tone remained increased in obese MSEW mice. In addition, acute boluses of angiotensin II (1, 10, 50 μg/kg s.c.) exerted a similar pressor response in MSEW and control mice before and after enalapril treatment. CONCLUSIONS Overall, elevated blood pressure and vasomotor sympathetic tone remained exacerbated in MSEW mice compared with controls after the peripheral inhibition of angiotensin-converting enzyme, suggesting a mechanism independent of angiotensin II.
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Affiliation(s)
- Carolina Dalmasso
- Department of Pharmacology and Nutritional SciencesUniversity of KentuckyLexingtonKYUSA
| | - Nermin S. Ahmed
- Department of Pharmacology and Nutritional SciencesUniversity of KentuckyLexingtonKYUSA
| | - Sundus Ghuneim
- Department of Pharmacology and Nutritional SciencesUniversity of KentuckyLexingtonKYUSA
| | - Cole Cincinelli
- Department of Pharmacology and Nutritional SciencesUniversity of KentuckyLexingtonKYUSA
| | - Jaqueline R. Leachman
- Department of Pharmacology and Nutritional SciencesUniversity of KentuckyLexingtonKYUSA
| | - Jorge F. Giani
- Department of Biomedical SciencesCedars‐Sinai Medical CenterLos AngelesCAUSA
| | - Lisa Cassis
- Department of Pharmacology and Nutritional SciencesUniversity of KentuckyLexingtonKYUSA
| | - Analia S. Loria
- Department of Pharmacology and Nutritional SciencesUniversity of KentuckyLexingtonKYUSA
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Althammer F, Roy RK, Kirchner MK, McGrath S, Lira EC, Stern JE. Angiotensin-II drives changes in microglia-vascular interactions in rats with heart failure. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.12.22.573045. [PMID: 38187537 PMCID: PMC10769361 DOI: 10.1101/2023.12.22.573045] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/09/2024]
Abstract
Activation of microglia, the resident immune cells of the central nervous system, leading to the subsequent release of pro-inflammatory cytokines, has been linked to cardiac remodeling, autonomic disbalance, and cognitive deficits in heart failure (HF). While previous studies emphasized the role of hippocampal Angiotensin II (AngII) signaling in HF-induced microglial activation, unanswered mechanistic questions persist. Evidence suggests significant interactions between microglia and local microvasculature, potentially affecting blood-brain barrier integrity and cerebral blood flow regulation. Still, whether the microglial-vascular interface is affected in the brain during HF remains unknow. Using a well-established ischemic HF rat model, we demonstrate increased vessel-associated microglia (VAM) in HF rat hippocampi, which showed heightened expression of AngII AT1a receptors. Acute AngII administration to sham rats induced microglia recruitment to the perivascular space, along with increased expression of TNFa. Conversely, administering an AT1aR blocker to HF rats prevented the recruitment of microglia to the perivascular space, normalizing their levels to those in healthy rats. These results highlight the critical importance of a rather understudied phenomenon (i.e., microglia-vascular interactions in the brain) in the context of the pathophysiology of a highly prevalent cardiovascular disease, and unveil novel potential therapeutic avenues aimed at mitigating neuroinflammation in cardiovascular diseases.
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Althammer F, Roy RK, Kirchner MK, Lira EC, Schimmer S, Charlet A, Grinevich V, Stern JE. Impaired oxytocin signaling in the central amygdala in rats with chronic heart failure. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.11.22.568271. [PMID: 38045233 PMCID: PMC10690294 DOI: 10.1101/2023.11.22.568271] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/05/2023]
Abstract
Aims Heart failure (HF) patients often suffer from cognitive decline, depression, and mood impairments, but the molecular signals and brain circuits underlying these effects remain elusive. The hypothalamic neuropeptide oxytocin (OT) is critically involved in the regulation of mood, and OTergic signaling in the central amygdala (CeA) is a key mechanism controlling emotional responses including anxiety-like behaviors. Based on this, we used in this study a well-established ischemic rat HF model and aimed to study alterations in the hypothalamus-to-CeA OTergic circuit. Methods and Results To study potential HF-induced changes in the hypothalamus-to-CeA OTertic circuit, we combined patch-clamp electrophysiology, immunohistochemical analysis, RNAScope assessment of OTR mRNA, brain region-specific stereotaxic injections of viral vectors and retrograde tracing, optogenetic stimulation and OT biosensors in the ischemic HF model. We found that most of OTergic innervation of the central amygdala (CeA) originated from the hypothalamic supraoptic nucleus (SON). While no differences in the numbers of SON→CeA OTertic neurons (or their OT content) was observed between sham and HF rats, we did observe a blunted content and release of OT from axonal terminals within the CeA. Moreover, we report downregulation of neuronal and astrocytic OT receptors, and impaired OTR-driven GABAergic synaptic activity within the CeA microcircuit of rats with HF. Conclusions Our study provides first evidence that HF rats display various perturbations in the hypothalamus-to-amygdala OTergic circuit, and lays the foundation for future translational studies targeting either the OT system or GABAergic amygdala GABA microcircuit to ameliorate depression or mood impairments in rats or patients with chronic HF.
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Affiliation(s)
- Ferdinand Althammer
- Center for Neuroinflammation and Cardiometabolic Diseases, Georgia State University, Atlanta, GA, USA
- Institute of Human Genetics, Heidelberg University, Heidelberg
| | - Ranjan K. Roy
- Center for Neuroinflammation and Cardiometabolic Diseases, Georgia State University, Atlanta, GA, USA
- Neuroscience Institute, Georgia State University, Atlanta, GA, USA
| | - Matthew K. Kirchner
- Center for Neuroinflammation and Cardiometabolic Diseases, Georgia State University, Atlanta, GA, USA
- Neuroscience Institute, Georgia State University, Atlanta, GA, USA
| | - Elba Campos Lira
- Center for Neuroinflammation and Cardiometabolic Diseases, Georgia State University, Atlanta, GA, USA
- Neuroscience Institute, Georgia State University, Atlanta, GA, USA
| | - Stephanie Schimmer
- Department of Neuropeptide Research in Psychiatry, Central Institute of Mental Health, Heidelberg University, Mannheim, Germany
| | - Alexandre Charlet
- Centre National de la Recherche Scientifique and University of Strasbourg, Institute of Cellular and Integrative Neuroscience, Strasbourg, France
| | - Valery Grinevich
- Department of Neuropeptide Research in Psychiatry, Central Institute of Mental Health, Heidelberg University, Mannheim, Germany
| | - Javier E. Stern
- Center for Neuroinflammation and Cardiometabolic Diseases, Georgia State University, Atlanta, GA, USA
- Neuroscience Institute, Georgia State University, Atlanta, GA, USA
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7
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Xi H, Li X, Zhou Y, Sun Y. The Regulatory Effect of the Paraventricular Nucleus on Hypertension. Neuroendocrinology 2023; 114:1-13. [PMID: 37598678 DOI: 10.1159/000533691] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/18/2023] [Accepted: 08/17/2023] [Indexed: 08/22/2023]
Abstract
Hypertension is among the most harmful factors of cardiovascular and cerebrovascular diseases and poses an urgent problem for the development of human society. In addition to previous studies on its pathogenesis focusing on the peripheral sympathetic nervous system, investigating the central causes of high blood pressure involving the neuroendocrine and neuroinflammatory mechanisms of the hypothalamic paraventricular nucleus (PVN) is paramount. This nucleus is considered to regulate the output of neurohormones and sympathetic nerve activity. In this article, we focussed on the neuroendocrine mechanism, primarily exploring the specific contributions and interactions of various neurons and neuroendocrine hormones, including GABAergic and glutamatergic neurons, nitric oxide, arginine vasopressin, oxytocin, and the renin-angiotensin system. Additionally, the neuroinflammatory mechanism in the PVN was discussed, encompassing microglia, reactive oxygen species, inflammatory factors, and pathways, as well as immune connections between the brain and extracerebral organs. Notably, the two central mechanisms involved in the PVN not only exist independently but also communicate with each other, jointly maintaining the hypertensive state of the body. Furthermore, we introduce well-known molecules and signal transduction pathways within the PVN that can play a regulatory role in the two mechanisms to provide a basis and inspire ideas for further research.
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Affiliation(s)
- Hanyu Xi
- The Fifth Clinical Medical College of Shanxi Medical University, Taiyuan, China
| | - Xingru Li
- The Fifth Clinical Medical College of Shanxi Medical University, Taiyuan, China
| | - Yun Zhou
- The Fifth Clinical Medical College of Shanxi Medical University, Taiyuan, China
- Department of Nephrology, Shanxi Provincial Integrated Traditional Chinese Medicine and Western Medicine Hospital, Taiyuan, China
| | - Yaojun Sun
- Key Laboratory of Cellular Physiology, Ministry of Education, Shanxi Medical University, Taiyuan, China
- School of Basic Medicine, Shanxi Medical University, Taiyuan, China
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8
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Althammer F, Roy RK, Kirchner MK, Campos-Lira E, Whitley KE, Davis S, Montanez J, Ferreira-Neto HC, Danh J, Feresin R, Biancardi VC, Zafar U, Parent MB, Stern JE. Angiotensin II-Mediated Neuroinflammation in the Hippocampus Contributes to Neuronal Deficits and Cognitive Impairment in Heart Failure Rats. Hypertension 2023; 80:1258-1273. [PMID: 37035922 PMCID: PMC10192104 DOI: 10.1161/hypertensionaha.123.21070] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2023] [Accepted: 03/22/2023] [Indexed: 04/11/2023]
Abstract
BACKGROUND Heart failure (HF) is a debilitating disease affecting >64 million people worldwide. In addition to impaired cardiovascular performance and associated systemic complications, most patients with HF suffer from depression and substantial cognitive decline. Although neuroinflammation and brain hypoperfusion occur in humans and rodents with HF, the underlying neuronal substrates, mechanisms, and their relative contribution to cognitive deficits in HF remains unknown. METHODS To address this critical gap in our knowledge, we used a well-established HF rat model that mimics clinical outcomes observed in the human population, along with a multidisciplinary approach combining behavioral, electrophysiological, neuroanatomical, molecular and systemic physiological approaches. RESULTS Our studies support neuroinflammation, hypoperfusion/hypoxia, and neuronal deficits in the hippocampus of HF rats, which correlated with the progression and severity of the disease. An increased expression of AT1aRs (Ang II [angiotensin II] receptor type 1a) in hippocampal microglia preceded the onset of neuroinflammation. Importantly, blockade of AT1Rs with a clinically used therapeutic drug (Losartan), and delivered in a clinically relevant manner, efficiently reversed neuroinflammatory end points (but not hypoxia ones), resulting in turn in improved cognitive performance in HF rats. Finally, we show than circulating Ang II can leak and access the hippocampal parenchyma in HF rats, constituting a possible source of Ang II initiating the neuroinflammatory signaling cascade in HF. CONCLUSIONS In this study, we identified a neuronal substrate (hippocampus), a mechanism (Ang II-driven neuroinflammation) and a potential neuroprotective therapeutic target (AT1aRs) for the treatment of cognitive deficits in HF.
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Affiliation(s)
- Ferdinand Althammer
- Center for Neuroinflammation and Cardiometabolic Diseases,
Georgia State University, GA, USA
| | - Ranjan K. Roy
- Center for Neuroinflammation and Cardiometabolic Diseases,
Georgia State University, GA, USA
| | - Matthew K. Kirchner
- Center for Neuroinflammation and Cardiometabolic Diseases,
Georgia State University, GA, USA
| | - Elba Campos-Lira
- Center for Neuroinflammation and Cardiometabolic Diseases,
Georgia State University, GA, USA
- Neuroscience Institute, Georgia State University, GA,
USA
| | | | - Steven Davis
- Neuroscience Institute, Georgia State University, GA,
USA
| | - Juliana Montanez
- Center for Neuroinflammation and Cardiometabolic Diseases,
Georgia State University, GA, USA
| | | | - Jessica Danh
- Department of Nutrition, Georgia State University, Atlanta,
GA 30302, USA
| | - Rafaela Feresin
- Department of Nutrition, Georgia State University, Atlanta,
GA 30302, USA
| | - Vinicia Campana Biancardi
- Anatomy, Physiology, & Pharmacology, College of
Veterinary Medicine, Auburn University, Auburn, AL, USA
| | - Usama Zafar
- Center for Neuroinflammation and Cardiometabolic Diseases,
Georgia State University, GA, USA
- Neuroscience Institute, Georgia State University, GA,
USA
| | - Marise B. Parent
- Center for Neuroinflammation and Cardiometabolic Diseases,
Georgia State University, GA, USA
- Neuroscience Institute, Georgia State University, GA,
USA
- Department of Psychology, Georgia State University,
Atlanta, GA 30302, USA
| | - Javier E. Stern
- Center for Neuroinflammation and Cardiometabolic Diseases,
Georgia State University, GA, USA
- Neuroscience Institute, Georgia State University, GA,
USA
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9
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Chapp AD, Collins AR, Driscoll KM, Behnke JE, Shan Z, Zhang L, Chen QH. Ethanol Metabolite, Acetate, Increases Excitability of the Central Nucleus of Amygdala Neurons through Activation of NMDA Receptors. ACS Chem Neurosci 2023; 14:1278-1290. [PMID: 36957993 PMCID: PMC11163875 DOI: 10.1021/acschemneuro.2c00784] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/25/2023] Open
Abstract
The central nucleus of the amygdala (CeA) is a key brain region involved in emotional and stressor responses due to its many projections to autonomic regulatory centers. It is also a primary site of action from ethanol consumption. However, the influence of active metabolites of ethanol such as acetate on the CeA neural circuitry has yet to be elucidated. Here, we investigated the effect of acetate on CeA neurons with the axon projecting to the rostral ventrolateral medulla (CeA-RVLM), as well as quantified cytosolic calcium responses in primary neuronal cultures. Whole-cell patch-clamp recordings in brain slices containing autonomic CeA-RVLM neurons revealed a dose-dependent increase in neuronal excitability in response to acetate. N-Methyl-d-aspartate receptor (NMDAR) antagonists suppressed the acetate-induced increase in CeA-RVLM neuronal excitability and memantine suppressed the direct activation of NMDAR-dependent inward currents by acetate in brain slices. We observed that acetate increased cytosolic Ca2+ in a time-dependent manner in primary neuronal cell cultures. The acetate enhancement of calcium signaling was abolished by memantine. Computational modeling of acetic acid at NMDAR/NR1 glutamatergic and glycinergic sites suggests potential active site interactions. These findings suggest that within the CeA, acetate is excitatory at least partially through activation of NMDAR, which may underlie the impact of ethanol consumption on autonomic circuitry.
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Affiliation(s)
- Andrew D Chapp
- Department of Kinesiology and Integrative Physiology, Michigan Technological University, SDC, 1400 Townsend Drive, Houghton, Michigan 49931, United States
- Department of Biological Sciences, Michigan Technological University, Houghton, Michigan 49931, United States
- Department of Neuroscience, University of Minnesota, Twin Cities, 321 Church Street SE, Minneapolis, Minnesota 55455, United States
| | - Andréa R Collins
- Department of Psychiatry, University of California, San Francisco, Fresno, California 93701, United States
| | - Kyle M Driscoll
- Department of Biological Sciences, Michigan Technological University, Houghton, Michigan 49931, United States
| | - Jessica E Behnke
- Department of Kinesiology and Integrative Physiology, Michigan Technological University, SDC, 1400 Townsend Drive, Houghton, Michigan 49931, United States
- Department of Biological Sciences, Michigan Technological University, Houghton, Michigan 49931, United States
| | - Zhiying Shan
- Department of Kinesiology and Integrative Physiology, Michigan Technological University, SDC, 1400 Townsend Drive, Houghton, Michigan 49931, United States
- Department of Biological Sciences, Michigan Technological University, Houghton, Michigan 49931, United States
| | - Li Zhang
- Laboratory for Integrative Neuroscience, National Institute on Alcohol Abuse and Alcoholism, National Institutes of Health, Rockville, Maryland 20852, United States
| | - Qing-Hui Chen
- Department of Kinesiology and Integrative Physiology, Michigan Technological University, SDC, 1400 Townsend Drive, Houghton, Michigan 49931, United States
- Department of Biological Sciences, Michigan Technological University, Houghton, Michigan 49931, United States
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10
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Tacke C, Bischoff AM, Harb A, Vafadari B, Hülsmann S. Angiotensin II increases respiratory rhythmic activity in the preBötzinger complex without inducing astroglial calcium signaling. Front Cell Neurosci 2023; 17:1111263. [PMID: 36816850 PMCID: PMC9932970 DOI: 10.3389/fncel.2023.1111263] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2022] [Accepted: 01/17/2023] [Indexed: 02/05/2023] Open
Abstract
Angiotensin II (Ang II) is the primary modulator of the renin-angiotensin system and has been widely studied for its effect on the cardiovascular system. While a few studies have also indicated an involvement of Ang II in the regulation of breathing, very little is known in this regard and its effect on brainstem respiratory regions such as the preBötzinger complex (preBötC), the kernel for inspiratory rhythm generation, has not been investigated yet. This study reports that Ang II temporarily increases phrenic nerve activity in the working heart-brainstem preparation, indicating higher central respiratory drive. Previous studies have shown that the carotid body is involved in mediating this effect and we revealed that the preBötC also plays a part, using acute slices of the brainstem. It appears that Ang II is increasing the respiratory drive in an AT1R-dependent manner by optimizing the interaction of inhibitory and excitatory neurons of the preBötC. Thus, Ang II-mediated effects on the preBötC are potentially involved in dysregulating breathing in patients with acute lung injury.
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11
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Oliveira KB, de Melo IS, da Silva BRM, Oliveira KLDS, Sabino-Silva R, Anhezini L, Katayama PL, Santos VR, Shetty AK, de Castro OW. SARS-CoV-2 and Hypertension: Evidence Supporting Invasion into the Brain Via Baroreflex Circuitry and the Role of Imbalanced Renin-Angiotensin-Aldosterone-System. Neurosci Insights 2023; 18:26331055231151926. [PMID: 36756280 PMCID: PMC9900164 DOI: 10.1177/26331055231151926] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2022] [Accepted: 01/04/2023] [Indexed: 02/05/2023] Open
Abstract
Hypertension is considered one of the most critical risk factors for COVID-19. Evidence suggests that SARS-CoV-2 infection produces intense effects on the cardiovascular system by weakening the wall of large vessels via vasa-vasorum. In this commentary, we propose that SARS-CoV-2 invades carotid and aortic baroreceptors, leading to infection of the nucleus tractus solitari (NTS) and paraventricular hypothalamic nucleus (PVN), and such dysregulation of NTS and PVN following infection causes blood pressure alteration at the central level. We additionally explored the hypothesis that SARS-CoV-2 favors the internalization of membrane ACE2 receptors generating an imbalance of the renin-angiotensin-aldosterone system (RAAS), increasing the activity of angiotensin II (ANG-II), disintegrin, and metalloproteinase 17 domain (ADAM17/TACE), eventually modulating the integration of afferents reaching the NTS from baroreceptors and promoting increased blood pressure. These mechanisms are related to the increased sympathetic activity, which leads to transient or permanent hypertension associated with SARS-CoV-2 invasion, contributing to the high number of deaths by cardiovascular implications.
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Affiliation(s)
- Kellysson Bruno Oliveira
- Department of Physiology, Institute of
Biological Sciences and Health, Federal University of Alagoas (UFAL), Maceió,
Alagoas, Brazil
| | - Igor Santana de Melo
- Department of Physiology, Institute of
Biological Sciences and Health, Federal University of Alagoas (UFAL), Maceió,
Alagoas, Brazil
| | - Bianca Rodrigues Melo da Silva
- Department of Physiology, Institute of
Biological Sciences and Health, Federal University of Alagoas (UFAL), Maceió,
Alagoas, Brazil
| | - Keylla Lavínia da Silva Oliveira
- Department of Physiology, Institute of
Biological Sciences and Health, Federal University of Alagoas (UFAL), Maceió,
Alagoas, Brazil
| | - Robinson Sabino-Silva
- Department of Physiology, Institute of
Biomedical Sciences, Federal University of Uberlandia (UFU), Uberlândia, Minas
Gerais, Brazil
| | - Lucas Anhezini
- Department of Histology, Institute of
Biological Sciences and Health, Federal University of Alagoas, Maceió, Alagoas,
Brazil
| | - Pedro Lourenco Katayama
- Department of Physiology and Pathology,
Dentistry School of Araraquara, São Paulo State University, Araraquara, São Paulo,
Brazil
| | - Victor Rodrigues Santos
- Department of Morphology, Institute of
Biological Science, Federal University of Minas Gerais (UFMG), Belo Horizonte, Minas
Gerais, Brazil
| | - Ashok K Shetty
- Institute for Regenerative Medicine,
Department of Cell Biology and Genetics, Texas A&M University School of
Medicine, College Station, TX, USA
| | - Olagide Wagner de Castro
- Department of Physiology, Institute of
Biological Sciences and Health, Federal University of Alagoas (UFAL), Maceió,
Alagoas, Brazil,Olagide Wagner de Castro, Institute of
Biological Sciences and Health, Federal University of Alagoas (UFAL), Av.
Lourival de Melo Mota, km 14, Campus A. C. Simões, Cidade Universitária, Maceió,
Alagoas CEP 57072-970, Brazil.
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12
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Lamptey RNL, Sun C, Layek B, Singh J. Neurogenic Hypertension, the Blood-Brain Barrier, and the Potential Role of Targeted Nanotherapeutics. Int J Mol Sci 2023; 24:ijms24032213. [PMID: 36768536 PMCID: PMC9916775 DOI: 10.3390/ijms24032213] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2022] [Revised: 01/13/2023] [Accepted: 01/16/2023] [Indexed: 01/26/2023] Open
Abstract
Hypertension is a major health concern globally. Elevated blood pressure, initiated and maintained by the brain, is defined as neurogenic hypertension (NH), which accounts for nearly half of all hypertension cases. A significant increase in angiotensin II-mediated sympathetic nervous system activity within the brain is known to be the key driving force behind NH. Blood pressure control in NH has been demonstrated through intracerebrovascular injection of agents that reduce the sympathetic influence on cardiac functions. However, traditional antihypertensive agents lack effective brain permeation, making NH management extremely challenging. Therefore, developing strategies that allow brain-targeted delivery of antihypertensives at the therapeutic level is crucial. Targeting nanotherapeutics have become popular in delivering therapeutics to hard-to-reach regions of the body, including the brain. Despite the frequent use of nanotherapeutics in other pathological conditions such as cancer, their use in hypertension has received very little attention. This review discusses the underlying pathophysiology and current management strategies for NH, as well as the potential role of targeted therapeutics in improving current treatment strategies.
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Affiliation(s)
| | | | - Buddhadev Layek
- Correspondence: (B.L.); (J.S.); Tel.: +1-701-231-7906 (B.L.); +1-701-231-7943 (J.S.); Fax: +1-701-231-8333 (B.L. & J.S.)
| | - Jagdish Singh
- Correspondence: (B.L.); (J.S.); Tel.: +1-701-231-7906 (B.L.); +1-701-231-7943 (J.S.); Fax: +1-701-231-8333 (B.L. & J.S.)
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13
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Ong WY, Satish RL, Herr DR. ACE2, Circumventricular Organs and the Hypothalamus, and COVID-19. Neuromolecular Med 2022; 24:363-373. [PMID: 35451691 PMCID: PMC9023728 DOI: 10.1007/s12017-022-08706-1] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2021] [Accepted: 03/01/2022] [Indexed: 12/29/2022]
Abstract
The SARS-CoV-2 virus gains entry to cells by binding to angiotensin-converting enzyme 2 (ACE2). Since circumventricular organs and parts of the hypothalamus lack a blood-brain barrier, and immunohistochemical studies demonstrate that ACE2 is highly expressed in circumventricular organs which are intimately connected to the hypothalamus, and the hypothalamus itself, these might be easy entry points for SARS-CoV-2 into the brain via the circulation. High ACE2 protein expression is found in the subfornical organ, area postrema, and the paraventricular nucleus of the hypothalamus (PVH). The subfornical organ and PVH are parts of a circuit to regulate osmolarity in the blood, through the secretion of anti-diuretic hormone into the posterior pituitary. The PVH is also the stress response centre in the brain. It controls not only pre-ganglionic sympathetic neurons, but is also a source of corticotropin-releasing hormone, that induces the secretion of adrenocorticotropic hormone from the anterior pituitary. It is proposed that the function of ACE2 in the circumventricular organs and the PVH could be diminished by binding with SARS-CoV-2, thus leading to a reduction in the ACE2/Ang (1-7)/Mas receptor (MasR) signalling axis, that modulates ACE/Ang II/AT1R signalling. This could result in increased presympathetic activity/neuroendocrine secretion from the PVH, and effects on the hypothalamic-pituitary-adrenal axis activity. Besides the bloodstream, the hypothalamus might also be affected by SARS-CoV-2 via transneuronal spread along the olfactory/limbic pathways. Exploring potential therapeutic pathways to prevent or attenuate neurological symptoms of COVID-19, including drugs which modulate ACE signalling, remains an important area of unmet medical need.
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Affiliation(s)
- Wei-Yi Ong
- Department of Anatomy, National University of Singapore, Singapore, 119260, Singapore.
- Neurobiology Research Programme, Life Sciences Institute, National University of Singapore, Singapore, 119260, Singapore.
| | - R L Satish
- Department of Anatomy, National University of Singapore, Singapore, 119260, Singapore
| | - Deron R Herr
- Department of Pharmacology, National University of Singapore, Singapore, 119260, Singapore
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14
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Herrera Moro Chao D, Kirchner MK, Pham C, Foppen E, Denis RGP, Castel J, Morel C, Montalban E, Hassouna R, Bui LC, Renault J, Mouffle C, García-Cáceres C, Tschöp MH, Li D, Martin C, Stern JE, Luquet SH. Hypothalamic astrocytes control systemic glucose metabolism and energy balance. Cell Metab 2022; 34:1532-1547.e6. [PMID: 36198294 PMCID: PMC9615252 DOI: 10.1016/j.cmet.2022.09.002] [Citation(s) in RCA: 26] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/23/2022] [Revised: 06/23/2022] [Accepted: 09/02/2022] [Indexed: 01/29/2023]
Abstract
The hypothalamus is key in the control of energy balance. However, strategies targeting hypothalamic neurons have failed to provide viable options to treat most metabolic diseases. Conversely, the role of astrocytes in systemic metabolic control has remained largely unexplored. Here, we show that obesity promotes anatomically restricted remodeling of hypothalamic astrocyte activity. In the paraventricular nucleus (PVN) of the hypothalamus, chemogenetic manipulation of astrocytes results in bidirectional control of neighboring neuron activity, autonomic outflow, glucose metabolism, and energy balance. This process recruits a mechanism involving the astrocytic control of ambient glutamate levels, which becomes defective in obesity. Positive or negative chemogenetic manipulation of PVN astrocyte Ca2+ signals, respectively, worsens or improves metabolic status of diet-induced obese mice. Collectively, these findings highlight a yet unappreciated role for astrocytes in the direct control of systemic metabolism and suggest potential targets for anti-obesity strategy.
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Affiliation(s)
| | - Matthew K Kirchner
- Neuroscience Institute, Georgia State University, Atlanta, GA 30303, USA; Center for Neuroinflammation and Cardiometabolic Diseases, Georgia State University, Atlanta, GA 30302, USA
| | - Cuong Pham
- Institute of Biology Paris Seine, Neuroscience Paris Seine, CNRS UMR8246, INSERM U1130, Sorbonne Universite, Paris 75005, France
| | - Ewout Foppen
- Université Paris Cité, CNRS, Unité de Biologie Fonctionnelle et Adaptative, Paris, France
| | - Raphael G P Denis
- Université Paris Cité, CNRS, Unité de Biologie Fonctionnelle et Adaptative, Paris, France; Institut Cochin, Université Paris Cité, INSERM U1016, CNRS UMR 8104, 75014 Paris, France
| | - Julien Castel
- Université Paris Cité, CNRS, Unité de Biologie Fonctionnelle et Adaptative, Paris, France
| | - Chloe Morel
- Université Paris Cité, CNRS, Unité de Biologie Fonctionnelle et Adaptative, Paris, France
| | - Enrica Montalban
- Université Paris Cité, CNRS, Unité de Biologie Fonctionnelle et Adaptative, Paris, France
| | - Rim Hassouna
- Université Paris Cité, CNRS, Unité de Biologie Fonctionnelle et Adaptative, Paris, France
| | - Linh-Chi Bui
- Université Paris Cité, CNRS, Unité de Biologie Fonctionnelle et Adaptative, Paris, France
| | - Justine Renault
- Université Paris Cité, CNRS, Unité de Biologie Fonctionnelle et Adaptative, Paris, France
| | - Christine Mouffle
- Institute of Biology Paris Seine, Neuroscience Paris Seine, CNRS UMR8246, INSERM U1130, Sorbonne Universite, Paris 75005, France
| | - Cristina García-Cáceres
- Helmholtz Diabetes Center (HDC) & German Center for Diabetes Research (DZD), Helmholtz Zentrum München, Neuherberg, 85764, Germany; Division of Metabolic Diseases, Technische Universität München, Munich, 80333, Germany; Medizinische Klinik and Poliklinik IV, Klinikum der Universität, Ludwig-Maximilians-Universität München, Munich, Germany
| | - Matthias H Tschöp
- Helmholtz Diabetes Center (HDC) & German Center for Diabetes Research (DZD), Helmholtz Zentrum München, Neuherberg, 85764, Germany; Division of Metabolic Diseases, Technische Universität München, Munich, 80333, Germany
| | - Dongdong Li
- Institute of Biology Paris Seine, Neuroscience Paris Seine, CNRS UMR8246, INSERM U1130, Sorbonne Universite, Paris 75005, France
| | - Claire Martin
- Université Paris Cité, CNRS, Unité de Biologie Fonctionnelle et Adaptative, Paris, France
| | - Javier E Stern
- Neuroscience Institute, Georgia State University, Atlanta, GA 30303, USA; Center for Neuroinflammation and Cardiometabolic Diseases, Georgia State University, Atlanta, GA 30302, USA
| | - Serge H Luquet
- Université Paris Cité, CNRS, Unité de Biologie Fonctionnelle et Adaptative, Paris, France.
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15
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Chen J, Chu Y, Gao M, Dai X, Li B, Qu X, Yin D. Cardiac sympathetic afferent ablation to prevent ventricular arrhythmia complicating acute myocardial infarction by inhibiting activated astrocytes. J Cell Mol Med 2022; 26:4805-4813. [PMID: 35934775 PMCID: PMC9465199 DOI: 10.1111/jcmm.17508] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2021] [Revised: 05/30/2022] [Accepted: 07/08/2022] [Indexed: 11/29/2022] Open
Abstract
Enhanced cardiac sympathetic afferent reflex (CSAR) contributes to ventricular arrhythmia (VA) after acute myocardial infarction (AMI). However, central regulation mechanisms remain unknown. The aim of this study was to investigate whether local cardiac sympathetic afferent ablation (LCSAA) could reduce VA by inhibiting activated astrocytes in the hypothalamus paraventricular (PVN) in an AMI rat model. The rats were randomly divided into AMI, AMI + BD (baroreceptor denervation), AMI + LCSAA and AMI + BD+ LCSAA groups. Before the generation of AMI, BD and (or) LCSAA were performed. At 24 h after AMI, the incidence and duration of VA in AMI + LCSAA group and AMI + BD + LCSAA group were significantly reduced than AMI group (P < 0.05). Furthermore, LCSAA significantly reduced GFAP (a marker for activated astrocytes) positive cells and their projections as well as the level of TNF‐α and IL‐6 in the PVN of AMI + LCSAA group and AMI + BD+ LCSAA group, along with the decrease of neuronal activation in PVN and sympathetic nerve activity (P < 0.05). but BD had no obvious difference between AMI + LCSAA and AMI + BD + LCSAA group (P > 0.05). Therefore, LCSAA could decrease sympathoexcitation and VA occurrence in AMI rats by inhibiting astrocyte and neuronal activation in the PVN. Our study demonstrates that activated astrocytes may play an important role on CSAR in AMI.
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Affiliation(s)
- Jugang Chen
- Department of Cardiology, The First Affiliated Hospital of Harbin Medical University, Harbin, China.,Department of Cardiology, Henan Provincial People's Hospital, People's Hospital of Zhengzhou University, Zhengzhou, China
| | - Yingjie Chu
- Department of Cardiology, Henan Provincial People's Hospital, People's Hospital of Zhengzhou University, Zhengzhou, China
| | - Meng Gao
- Department of Cardiology, The First Affiliated Hospital of Harbin Medical University, Harbin, China
| | - Xin Dai
- Department of Oncology, The First Affiliated Hospital of Harbin Medical University, Harbin, China
| | - Bin Li
- Department of Cardiology, The First Affiliated Hospital of Harbin Medical University, Harbin, China
| | - Xiufen Qu
- Department of Cardiology, The First Affiliated Hospital of Harbin Medical University, Harbin, China
| | - Dechun Yin
- Department of Cardiology, The First Affiliated Hospital of Harbin Medical University, Harbin, China
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16
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Zhu L, Huang L, Le A, Wang TJ, Zhang J, Chen X, Wang J, Wang J, Jiang C. Interactions between the Autonomic Nervous System and the Immune System after Stroke. Compr Physiol 2022; 12:3665-3704. [PMID: 35766834 DOI: 10.1002/cphy.c210047] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Acute stroke is one of the leading causes of morbidity and mortality worldwide. Stroke-induced immune-inflammatory response occurs in the perilesion areas and the periphery. Although stroke-induced immunosuppression may alleviate brain injury, it hinders brain repair as the immune-inflammatory response plays a bidirectional role after acute stroke. Furthermore, suppression of the systemic immune-inflammatory response increases the risk of life-threatening systemic bacterial infections after acute stroke. Therefore, it is essential to explore the mechanisms that underlie the stroke-induced immune-inflammatory response. Autonomic nervous system (ANS) activation is critical for regulating the local and systemic immune-inflammatory responses and may influence the prognosis of acute stroke. We review the changes in the sympathetic and parasympathetic nervous systems and their influence on the immune-inflammatory response after stroke. Importantly, this article summarizes the mechanisms on how ANS regulates the immune-inflammatory response through neurotransmitters and their receptors in immunocytes and immune organs after stroke. To facilitate translational research, we also discuss the promising therapeutic approaches modulating the activation of the ANS or the immune-inflammatory response to promote neurologic recovery after stroke. © 2022 American Physiological Society. Compr Physiol 12:3665-3704, 2022.
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Affiliation(s)
- Li Zhu
- Department of Neurology, The Fifth Affiliated Hospital of Zhengzhou University, Zhengzhou, PR China
| | - Leo Huang
- Department of Psychology, University of Toronto, Toronto, Ontario, Canada
| | - Anh Le
- Washington University in St. Louis, Saint Louis, Missouri, USA
| | - Tom J Wang
- Winston Churchill High School, Potomac, Maryland, USA
| | - Jiewen Zhang
- Department of Neurology, People's Hospital of Zhengzhou University, Zhengzhou, PR China
| | - Xuemei Chen
- Department of Anatomy, School of Basic Medical Sciences, Zhengzhou University, Zhengzhou, PR China
| | - Junmin Wang
- Department of Anatomy, School of Basic Medical Sciences, Zhengzhou University, Zhengzhou, PR China
| | - Jian Wang
- Department of Neurology, The Fifth Affiliated Hospital of Zhengzhou University, Zhengzhou, PR China.,Department of Anatomy, School of Basic Medical Sciences, Zhengzhou University, Zhengzhou, PR China
| | - Chao Jiang
- Department of Neurology, The Fifth Affiliated Hospital of Zhengzhou University, Zhengzhou, PR China
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17
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Roy RK, Ferreira-Neto HC, Felder RB, Stern JE. Angiotensin II inhibits the A-type K + current of hypothalamic paraventricular nucleus neurons in rats with heart failure: role of MAPK-ERK1/2 signaling. Am J Physiol Regul Integr Comp Physiol 2022; 322:R526-R534. [PMID: 35319903 PMCID: PMC9076419 DOI: 10.1152/ajpregu.00308.2021] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2021] [Revised: 03/03/2022] [Accepted: 03/18/2022] [Indexed: 11/22/2022]
Abstract
Angiotensin II (ANG II)-mediated sympathohumoral activation constitutes a pathophysiological mechanism in heart failure (HF). Although the hypothalamic paraventricular nucleus (PVN) is a major site mediating ANG II effects in HF, the precise mechanisms by which ANG II influences sympathohumoral outflow from the PVN remain unknown. ANG II activates the ubiquitous intracellular MAPK signaling cascades, and recent studies revealed a key role for ERK1/2 MAPK signaling in ANG II-mediated sympathoexcitation in HF rats. Importantly, ERK1/2 was reported to inhibit the transient outward potassium current (IA) in hippocampal neurons. Given that IA is a critical determinant of the PVN neuronal excitability, and that downregulation of IA in the brain has been reported in cardiovascular disease states, including HF, we investigated here whether ANG II modulates IA in PVN neurons via the MAPK-ERK pathway, and, whether these effects are altered in HF rats. Patch-clamp recordings from identified magnocellular neurosecretory neurons (MNNs) and presympathetic (PS) PVN neurons revealed that ANG II inhibited IA in both PVN neuronal types, both in sham and HF rats. Importantly, ANG II effects were blocked by inhibiting MAPK-ERK signaling as well as by inhibiting epidermal growth factor receptor (EGFR), a gateway to MAPK-ERK signaling. Although no differences in basal IA magnitude were found between sham and HF rats under normal conditions, MAPK-ERK blockade resulted in significantly larger IA in both PVN neuronal types in HF rats. Taken together, our studies show that ANG II-induced ERK1/2 activity inhibits IA, an effect expected to increase the excitability of presympathetic and neuroendocrine PVN neurons, contributing in turn to the neurohumoral overactivity that promotes progression of the HF syndrome.
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Affiliation(s)
- Ranjan K Roy
- Neuroscience Institute, Georgia State University, Atlanta, Georgia
| | | | - Robert B Felder
- Division of Cardiovascular Medicine, Department of Internal Medicine, University of Iowa Carver College of Medicine, Iowa City, Iowa
| | - Javier E Stern
- Neuroscience Institute, Georgia State University, Atlanta, Georgia
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18
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Zhu X, Li K, Gao Y. Adeno-associated virus-mediated in vivo suppression of expression of EPHX2 gene modulates the activity of paraventricular nucleus neurons in spontaneously hypertensive rats. Biochem Biophys Res Commun 2022; 606:121-127. [PMID: 35344709 DOI: 10.1016/j.bbrc.2022.03.084] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2022] [Accepted: 03/16/2022] [Indexed: 11/29/2022]
Abstract
BACKGROUND Hypertension can be attributed to increased sympathetic activities. Presympathetic neurons in the paraventricular nucleus (PVN) of the hypothalamus are capable of modulating sympathetic outflow, thus contributing to the pathogenesis of neurogenic hypertension. Epoxyeicosatrienoic acids (EETs) were reported to have anti-hypertensive effects, which could be degraded by soluble epoxide hydrolase (sEH), encoded by EPHX2. However, the potential effect of EETs on PVN neuron activity and the underlying molecular mechanism are largely unknown. METHODS Knockdown of EPHX2 in spontaneously hypertensive rats (SHRs) was achieved by tail-intravenous injection of AAV plasmid containing shRNA targeting EPHX2. Whole-cell patch clamp was used to record action potentials of PVN neurons. An LC-MS/MS System was employed to determine 14,15-EET levels in rat cerebrospinal fluid. qPCR and western blotting were applied to examine the expression level of EPHX2 in various tissues. ELISA and immunofluorescence staining were applied to examine the levels of ATP, D-serine and glial fibrillary acidic protein (GFAP) in isolated astrocytes. RESULTS The expression level of EPHX2 was higher, while the level of 14,15-EET was lower in SHRs than normotensive Wistar-Kyoto rats (WKY) rats. The spike firing frequency of PNV neurons in SHRs was higher than in WKY rats at a given stimulus current, which could be reduced by either EPHX2 downregulation or 14,15-EET administration. In isolated hypothalamic astrocytes, the elevated intracellular ATP or D-serine induced by Angiotensin II (Ang II) treatment could be rescued by 14,15-EET addition or 14,15-EET combing serine racemase (SR) downregulation by siRNA, respectively. Furthermore, 14,15-EET treatment reduced the Ang II-induced elevation of GFAP immunofluorescence. CONCLUSIONS The elevation of EET levels by EPHX2 downregulation reduced presympathetic neuronal activity in the PVN of SHRs, leading to a reduced sympathetic outflow in hypertension rats. The ATP/SR/D-serine pathway of astrocytes is involved in EET-mediated neuroprotection.
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Affiliation(s)
- Xiaoming Zhu
- Heart Center and Beijing Key Laboratory of Hypertension, Beijing Chaoyang Hospital, Capital Medical University, Beijing, China.
| | - Kuibao Li
- Heart Center and Beijing Key Laboratory of Hypertension, Beijing Chaoyang Hospital, Capital Medical University, Beijing, China.
| | - Yuanfeng Gao
- Heart Center and Beijing Key Laboratory of Hypertension, Beijing Chaoyang Hospital, Capital Medical University, Beijing, China.
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19
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Souders CL, Zubcevic J, Martyniuk CJ. Tumor Necrosis Factor Alpha and the Gastrointestinal Epithelium: Implications for the Gut-Brain Axis and Hypertension. Cell Mol Neurobiol 2022; 42:419-437. [PMID: 33594519 PMCID: PMC8364923 DOI: 10.1007/s10571-021-01044-z] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2020] [Accepted: 01/11/2021] [Indexed: 12/17/2022]
Abstract
The colonic epithelium is the site of production and transport of many vasoactive metabolites and neurotransmitters that can modulate the immune system, affect cellular metabolism, and subsequently regulate blood pressure. As an important interface between the microbiome and its host, the colon can contribute to the development of hypertension. In this critical review, we highlight the role of colonic inflammation and microbial metabolites on the gut brain axis in the pathology of hypertension, with special emphasis on the interaction between tumor necrosis factor α (TNFα) and short chain fatty acid (SCFA) metabolites. Here, we review the current literature and identify novel pathways in the colonic epithelium related to hypertension. A network analysis on transcriptome data previously generated in spontaneously hypertensive rats (SHR) and Wistar-Kyoto (WKY) rats reveals differences in several pathways associated with inflammation involving TNFα (NF-κB and STAT Expression Targets) as well as oxidative stress. We also identify down-regulation of networks associated with gastrointestinal function, cardiovascular function, enteric nervous system function, and cholinergic and adrenergic transmission. The analysis also uncovered transcriptome responses related to glycolysis, butyrate oxidation, and mitochondrial function, in addition to gut neuropeptides that serve as modulators of blood pressure and metabolic function. We present a model for the role of TNFα in regulating bacterial metabolite transport and neuropeptide signaling in the gastrointestinal system, highlighting the complexity of host-microbiota interactions in hypertension.
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Affiliation(s)
- Christopher L. Souders
- Department of Physiological Sciences and Center for Environmental and Human Toxicology, University of Florida Genetics Institute, Interdisciplinary Program in Biomedical Sciences Neuroscience, College of Veterinary Medicine, University of Florida, Gainesville, FL, 32611 USA
| | - Jasenka Zubcevic
- Department of Physiological Sciences and Center for Environmental and Human Toxicology, University of Florida Genetics Institute, Interdisciplinary Program in Biomedical Sciences Neuroscience, College of Veterinary Medicine, University of Florida, Gainesville, FL, 32611, USA. .,Department of Physiological Sciences, College of Veterinary Medicine, University of Florida, PO BOX 100274, Gainesville, FL, 32611, USA.
| | - Christopher J. Martyniuk
- Department of Physiological Sciences and Center for Environmental and Human Toxicology, University of Florida Genetics Institute, Interdisciplinary Program in Biomedical Sciences Neuroscience, College of Veterinary Medicine, University of Florida, Gainesville, FL, 32611 USA,Corresponding authors contact information: Department of Physiological Sciences, College of Veterinary Medicine, University of Florida PO BOX 100274 GAINESVILLE FL 326100274 United States; and
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20
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Wu H, Sun Q, Yuan S, Wang J, Li F, Gao H, Chen X, Yang R, Xu J. AT1 Receptors: Their Actions from Hypertension to Cognitive Impairment. Cardiovasc Toxicol 2022; 22:311-325. [PMID: 35211833 PMCID: PMC8868040 DOI: 10.1007/s12012-022-09730-0] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/11/2021] [Accepted: 02/07/2022] [Indexed: 12/18/2022]
Abstract
Hypertension is one of the most prevalent cardiovascular disorders worldwide, affecting 1.13 billion people, or 14% of the global population. Hypertension is the single biggest risk factor for cerebrovascular dysfunction. According to the American Heart Association, high blood pressure (BP), especially in middle-aged individuals (~ 40 to 60 years old), is associated with an increased risk of dementia, later in life. Alzheimer’s disease and cerebrovascular disease are the two leading causes of dementia, accounting for around 80% of the total cases and usually combining mixed pathologies from both. Little is known regarding how hypertension affects cognitive function, so the impact of its treatment on cognitive impairment has been difficult to assess. The brain renin-angiotensin system (RAS) is essential for BP regulation and overactivity of this system has been established to precede the development and maintenance of hypertension. Angiotensin II (Ang-II), the main peptide within this system, induces vasoconstriction and impairs neuro-vascular coupling by acting on brain Ang-II type 1 receptors (AT1R). In this review, we systemically analyzed the association between RAS and biological mechanisms of cognitive impairment, from the perspective of AT1R located in the central nervous system. Additionally, the possible contribution of brain AT1R to global cognition decline in COVID-19 cases will be discussed as well.
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Affiliation(s)
- Hanxue Wu
- Department of Physiology and Pathophysiology, School of Medicine, Xi'an Jiaotong University, 76 West Yanta Road, Xi'an, 710061, China
| | - Qi Sun
- The First Affiliated Hospital of Xi'an Jiaotong University, Xi'an, 710061, China
| | - Shenglan Yuan
- Department of Physiology and Pathophysiology, School of Medicine, Xi'an Jiaotong University, 76 West Yanta Road, Xi'an, 710061, China
| | - Jiawei Wang
- Department of Physiology and Pathophysiology, School of Medicine, Xi'an Jiaotong University, 76 West Yanta Road, Xi'an, 710061, China
| | - Fanni Li
- The First Affiliated Hospital of Xi'an Jiaotong University, Xi'an, 710061, China
| | - Hongli Gao
- Department of Physiology and Pathophysiology, School of Medicine, Xi'an Jiaotong University, 76 West Yanta Road, Xi'an, 710061, China
| | - Xingjuan Chen
- Institute of Medical Research, Northwestern Polytechnical University, Xi'an, 710072, China
| | - Rui Yang
- Department of Physiology and Pathophysiology, School of Medicine, Xi'an Jiaotong University, 76 West Yanta Road, Xi'an, 710061, China
| | - Jiaxi Xu
- Department of Physiology and Pathophysiology, School of Medicine, Xi'an Jiaotong University, 76 West Yanta Road, Xi'an, 710061, China.
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21
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Mowry FE, Peaden SC, Stern JE, Biancardi VC. TLR4 and AT1R mediate blood-brain barrier disruption, neuroinflammation, and autonomic dysfunction in spontaneously hypertensive rats. Pharmacol Res 2021; 174:105877. [PMID: 34610452 PMCID: PMC8648989 DOI: 10.1016/j.phrs.2021.105877] [Citation(s) in RCA: 30] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/28/2021] [Revised: 09/03/2021] [Accepted: 09/05/2021] [Indexed: 01/23/2023]
Abstract
Angiotensin II (AngII) is implicated in neuroinflammation, blood-brain barrier (BBB) disruption, and autonomic dysfunction in hypertension. We have previously shown that exogenous AngII stimulates Toll-like receptor 4 (TLR4) via AngII type 1 receptor (AT1R), inducing activation of hypothalamic microglia ex vivo, and that AngII-AT1R signaling is necessary for the loss of BBB integrity in spontaneously hypertensive rats (SHRs). Herein, we hypothesized that microglial TLR4 and AT1R signaling interactions represent a crucial mechanistic link between AngII-mediated neuroinflammation and BBB disruption, thereby contributing to sympathoexcitation in SHRs. Male SHRs were treated with TAK-242 (TLR4 inhibitor; 2 weeks), Losartan (AT1R inhibitor; 4 weeks), or vehicle, and age-matched to control Wistar Kyoto rats (WKYs). TLR4 and AT1R inhibitions normalized increased TLR4, interleukin-6, and tumor necrosis factor-α protein densities in SHR cardioregulatory nuclei (hypothalamic paraventricular nucleus [PVN], rostral ventrolateral medulla [RVLM], and nucleus tractus solitarius [NTS]), and abolished enhanced microglial activation. PVN, RVLM, and NTS BBB permeability analyses revealed complete restoration after TAK-242 treatment, whereas SHRs presented with elevated dye leakage. Mean arterial pressure was normalized in Losartan-treated SHRs, and attenuated with TLR4 inhibition. In conscious assessments, TLR4 blockade rescued SHR baroreflex sensitivity to vasoactive drugs, and reduced the SHR pressor response to ganglionic blockade to normal levels. These data suggest that TLR4 activation plays a substantial role in mediating a feed-forward pro-hypertensive cycle involving BBB disruption, neuroinflammation, and autonomic dysfunction, and that TLR4-specific therapeutic interventions may represent viable alternatives in the treatment of hypertension.
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Affiliation(s)
- Francesca E Mowry
- Department of Anatomy, Physiology & Pharmacology, College of Veterinary Medicine, Auburn University, Auburn, AL, USA; Center for Neurosciences Initiative, Auburn University, Auburn, AL, USA
| | - Sarah C Peaden
- Department of Anatomy, Physiology & Pharmacology, College of Veterinary Medicine, Auburn University, Auburn, AL, USA
| | - Javier E Stern
- Center for Neuroinflammation, Georgia State University, Atlanta, GA, USA
| | - Vinicia C Biancardi
- Department of Anatomy, Physiology & Pharmacology, College of Veterinary Medicine, Auburn University, Auburn, AL, USA; Center for Neurosciences Initiative, Auburn University, Auburn, AL, USA.
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Per- and Polyfluoroalkyl Substances (PFAS) in Integrated Crop-Livestock Systems: Environmental Exposure and Human Health Risks. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2021; 18:ijerph182312550. [PMID: 34886275 PMCID: PMC8657007 DOI: 10.3390/ijerph182312550] [Citation(s) in RCA: 31] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/16/2021] [Revised: 11/19/2021] [Accepted: 11/25/2021] [Indexed: 11/17/2022]
Abstract
Per- and polyfluoroalkyl substances (PFAS) are highly persistent synthetic organic contaminants that can cause serious human health concerns such as obesity, liver damage, kidney cancer, hypertension, immunotoxicity and other human health issues. Integrated crop–livestock systems combine agricultural crop production with milk and/or meat production and processing. Key sources of PFAS in these systems include firefighting foams near military bases, wastewater sludge and industrial discharge. Per- and polyfluoroalkyl substances regularly move from soils to nearby surface water and/or groundwater because of their high mobility and persistence. Irrigating crops or managing livestock for milk and meat production using adjacent waters can be detrimental to human health. The presence of PFAS in both groundwater and milk have been reported in dairy production states (e.g., Wisconsin and New Mexico) across the United States. Although there is a limit of 70 parts per trillion of PFAS in drinking water by the U.S. EPA, there are not yet regional screening guidelines for conducting risk assessments of livestock watering as well as the soil and plant matrix. This systematic review includes (i) the sources, impacts and challenges of PFAS in integrated crop–livestock systems, (ii) safety measures and protocols for sampling soil, water and plants for determining PFAS concentration in exposed integrated crop–livestock systems and (iii) the assessment, measurement and evaluation of human health risks related to PFAS exposure.
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Angiotensin II and the Cardiac Parasympathetic Nervous System in Hypertension. Int J Mol Sci 2021; 22:ijms222212305. [PMID: 34830184 PMCID: PMC8624735 DOI: 10.3390/ijms222212305] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2021] [Revised: 11/09/2021] [Accepted: 11/10/2021] [Indexed: 01/08/2023] Open
Abstract
The renin-angiotensin-aldosterone system (RAAS) impacts cardiovascular homeostasis via direct actions on peripheral blood vessels and via modulation of the autonomic nervous system. To date, research has primarily focused on the actions of the RAAS on the sympathetic nervous system. Here, we review the critical role of the RAAS on parasympathetic nerve function during normal physiology and its role in cardiovascular disease, focusing on hypertension. Angiotensin (Ang) II receptors are present throughout the parasympathetic nerves and can modulate vagal activity via actions at the level of the nerve endings as well as via the circumventricular organs and as a neuromodulator acting within brain regions. There is tonic inhibition of cardiac vagal tone by endogenous Ang II. We review the actions of Ang II via peripheral nerve endings as well as via central actions on brain regions. We review the evidence that Ang II modulates arterial baroreflex function and examine the pathways via which Ang II can modulate baroreflex control of cardiac vagal drive. Although there is evidence that Ang II can modulate parasympathetic activity and has the potential to contribute to impaired baseline levels and impaired baroreflex control during hypertension, the exact central regions where Ang II acts need further investigation. The beneficial actions of angiotensin receptor blockers in hypertension may be mediated in part via actions on the parasympathetic nervous system. We highlight important unknown questions about the interaction between the RAAS and the parasympathetic nervous system and conclude that this remains an important area where future research is needed.
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Pittman QJ. Vasopressin and central control of the cardiovascular system: A 40-year retrospective. J Neuroendocrinol 2021; 33:e13011. [PMID: 34235812 DOI: 10.1111/jne.13011] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/26/2021] [Accepted: 06/25/2021] [Indexed: 01/24/2023]
Abstract
In the 40 years since vasopressin (AVP) was reported to have a central action with respect to raising blood pressure, the finding has been repeatedly replicated using a variety of complimentary approaches. The role of AVP as a central neurotransmitter involved in control of the cardiovascular system is now textbook material. However, it is evident that brain AVP plays, at best, a minor role in regulation of normal blood pressure. However, it appears to be an important player in a several cardiovascular-associated pathologies, ranging from hypertension to neural changes associated with heart failure. There are many interventions that have been shown to affect neural function, many of which are associated with alterations in behaviour. Possible alterations in neuronal AVP actions relevant to cardiovascular control in the setting of chronic inflammatory disease, early-life stress and inflammation are suggested areas for future research.
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Affiliation(s)
- Quentin J Pittman
- Department of Physiology and Pharmacology, Hotchkiss Brain Institute, University of Calgary, Calgary, AB, Canada
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25
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Cross-Talk between TNF-α and Angiotensin II in the Neural Control of Hypertension. J Neurosci 2021; 41:7512-7513. [PMID: 34497131 DOI: 10.1523/jneurosci.0193-21.2021] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2021] [Revised: 07/06/2021] [Accepted: 07/19/2021] [Indexed: 11/21/2022] Open
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Ferreira-Neto HC, Antunes VR, Stern JE. Purinergic P2 and glutamate NMDA receptor coupling contributes to osmotically driven excitability in hypothalamic magnocellular neurosecretory neurons. J Physiol 2021; 599:3531-3547. [PMID: 34053068 DOI: 10.1113/jp281411] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2021] [Accepted: 05/28/2021] [Indexed: 11/08/2022] Open
Abstract
KEY POINTS Purinergic and glutamatergic signalling pathways play a key role in regulating the activity of hypothalamic magnocellular neurosecretory neurons (MNNs). However, the precise cellular mechanisms by which ATP and glutamate act in concert to regulate osmotically driven MNN neuronal excitability remains unknown. Here, we report that ATP acts on purinergic P2 receptors in MNNs to potentiate in a Ca2+ -dependent manner extrasynaptic NMDAR function. The P2-NMDAR coupling is engaged in response to an acute hyperosmotic stimulation, contributing to osmotically driven firing activity in MNNs. These results help us to better understand the precise mechanisms contributing to the osmotic regulation of firing activity and hormone release from MNNs. ABSTRACT The firing activity of hypothalamic magnocellular neurosecretory neurons (MNNs) located in the paraventricular nucleus (PVN) and supraoptic nucleus (SON) is coordinated by the combined, fine-tuned action of intrinsic membrane properties, synaptic and extrasynaptic signalling. Among these, purinergic and glutamatergic signalling pathways have been shown to play a key role regulating the activity of MNNs. However, the precise cellular mechanisms by which ATP and glutamate act in concert to regulate osmotically driven MNN neuronal excitability remains unknown. Whole-cell patch-clamp recordings obtained from MNNs showed that ATP (100 μM) induced an increase in firing rate, an effect that was blocked by either 4-[[4-formyl-5-hydroxy-6-methyl-3-[(phosphonooxy)methyl]2-pyridinyl]azo]1,3-benzenedisulfonic acid tetrasodium salt (PPADS) (10 μM) or kynurenic acid (1 mm). While ATP did not affect the frequency or magnitude of glutamatergic excitatory postsynaptic currents (EPSCs), it induced an inward shift in the holding current that was prevented by PPADS or kynurenic acid treatment, suggesting that ATP enhances a tonic extrasynaptic glutamatergic excitatory current. We observed that ATP-potentiated glutamatergic receptor-mediated currents were evoked by focal application of L-glu (1 mm) and NMDA (50 μM), but not AMPA (50 μM). ATP potentiation of NMDA-evoked currents was blocked by PPADS (10 μM) and by chelation of intracellular Ca2+ with BAPTA (10 mm). Finally, we report that a hyperosmotic stimulus (mannitol 1%, +55 mOsm/kgH2 O) potentiated NMDA-evoked currents and increased MNN firing activity, effects that were blocked by PPADS. Taken together, our data support a functional excitatory coupling between P2 and extrasynaptic NMDA receptors in MNNs, which is engaged in response to an acute hyperosmotic stimulus.
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Affiliation(s)
- H C Ferreira-Neto
- Neuroscience Institute, Georgia State University, Atlanta, Georgia, USA
| | - V R Antunes
- Department of Physiology and Biophysics, Institute of Biomedical Sciences, University of Sao Paulo, Sao Paulo, Brazil
| | - J E Stern
- Neuroscience Institute, Georgia State University, Atlanta, Georgia, USA
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Kawarazaki W, Fujita T. Kidney and epigenetic mechanisms of salt-sensitive hypertension. Nat Rev Nephrol 2021; 17:350-363. [PMID: 33627838 DOI: 10.1038/s41581-021-00399-2] [Citation(s) in RCA: 33] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 01/21/2021] [Indexed: 02/07/2023]
Abstract
Dietary salt intake increases blood pressure (BP) but the salt sensitivity of BP differs between individuals. The interplay of ageing, genetics and environmental factors, including malnutrition and stress, contributes to BP salt sensitivity. In adults, obesity is often associated with salt-sensitive hypertension. The children of women who experience malnutrition during pregnancy are at increased risk of developing obesity, diabetes and salt-sensitive hypertension as adults. Similarly, the offspring of mice that are fed a low-protein diet during pregnancy develop salt-sensitive hypertension in association with aberrant DNA methylation of the gene encoding type 1A angiotensin II receptor (AT1AR) in the hypothalamus, leading to upregulation of hypothalamic AT1AR and renal sympathetic overactivity. Ageing is also associated with salt-sensitive hypertension. In aged mice, promoter methylation leads to reduced kidney production of the anti-ageing factor Klotho and a decrease in circulating soluble Klotho. In the setting of Klotho deficiency, salt-induced activation of the vascular Wnt5a-RhoA pathway leads to ageing-associated salt-sensitive hypertension, potentially as a result of reduced renal blood flow and increased peripheral resistance. Thus, kidney mechanisms and aberrant DNA methylation of certain genes are involved in the development of salt-sensitive hypertension during fetal development and old age. Three distinct paradigms of epigenetic memory operate on different timescales in prenatal malnutrition, obesity and ageing.
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Affiliation(s)
- Wakako Kawarazaki
- Division of Clinical Epigenetics, Research Center for Advanced Science and Technology, The University of Tokyo, Tokyo, Japan
| | - Toshiro Fujita
- Division of Clinical Epigenetics, Research Center for Advanced Science and Technology, The University of Tokyo, Tokyo, Japan. .,School of Medicine, Shinshu University, Matsumoto, Japan. .,Research Center for Social Systems, Shinshu University, Matsumoto, Japan.
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28
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Brain angiotensin converting enzyme-2 in central cardiovascular regulation. Clin Sci (Lond) 2021; 134:2535-2547. [PMID: 33016313 DOI: 10.1042/cs20200483] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2020] [Revised: 09/18/2020] [Accepted: 09/22/2020] [Indexed: 12/24/2022]
Abstract
The brain renin-angiotensin system (RAS) plays an important role in the regulation of autonomic and neuroendocrine functions, and maintains cardiovascular homeostasis. Ang-II is the major effector molecule of RAS and exerts most of its physiological functions, including blood pressure (BP) regulation, via activation of AT1 receptors. Dysregulation of brain RAS in the central nervous system results in increased Ang-II synthesis that leads to sympathetic outflow and hypertension. Brain angiotensin (Ang) converting enzyme-2 (ACE2) was discovered two decades ago as an RAS component, exhibiting a counter-regulatory role and opposing the adverse cardiovascular effects produced by Ang-II. Studies using synthetic compounds that can sustain the elevation of ACE2 activity or genetically overexpressed ACE2 in specific brain regions found various beneficial effects on cardiovascular function. More recently, ACE2 has been shown to play critical roles in neuro-inflammation, gut dysbiosis and the regulation of stress and anxiety-like behaviors. In the present review, we aim to highlight the anatomical locations and functional implication of brain ACE2 related to its BP regulation via modulation of the sympathetic nervous system and discuss the recent developments and future directions in the ACE2-mediated central cardiovascular regulation.
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29
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Abstract
Current experimental stroke research has evolved to focus on detailed understanding of the brain’s self-protective and restorative mechanisms, and harness this knowledge for development of new therapies. In this context, the role of peptidases and neuropeptides is of growing interest. In this focused review, peptidase neurolysin (Nln) and its extracellular peptide substrates are briefly discussed in relation to pathophysiology of ischemic stroke. Upregulation of Nln following stroke is viewed as a compensatory cerebroprotective mechanism in the acute phase of stroke, because the main neuropeptides inactivated by Nln are neuro/cerebrotoxic (bradykinin, substance P, neurotensin, angiotensin II, hemopressin), whereas the peptides generated by Nln are neuro/cerebroprotective (angiotensin-(1–7), Leu-/Met-enkephalins). This notion is confirmed by experimental studies documenting aggravation of stroke outcomes in mice after inhibition of Nln following stroke, and dramatic improvement of stroke outcomes in mice overexpressing Nln in the brain. The role of Nln in the (sub)chronic phase of stroke is less clear and it is likely, that this peptidase does not have a major role in neural repair mechanisms. This is because, the substrates of Nln are less uniform in modulating neurorestorative mechanisms in one direction, some appearing to have neural repair enhancing/stimulating potential, whereas others doing the opposite. Future studies focusing on the role of Nln in pathophysiology of stroke should determine its potential as a cerebroprotective target for stroke therapy, because its unique ability to modulate multiple neuropeptide systems critically involved in brain injury mechanisms is likely advantageous over modulation of one pathogenic pathway for stroke pharmacotherapy.
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Affiliation(s)
- Vardan T Karamyan
- Department of Pharmaceutical Sciences and Center for Blood Brain Barrier Research, School of Pharmacy, TTUHSC, Amarillo, TX, USA
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30
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Hirooka Y. Sympathetic Activation in Hypertension: Importance of the Central Nervous System. Am J Hypertens 2020; 33:914-926. [PMID: 32374869 DOI: 10.1093/ajh/hpaa074] [Citation(s) in RCA: 25] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2020] [Revised: 04/18/2020] [Accepted: 05/01/2020] [Indexed: 12/20/2022] Open
Abstract
The sympathetic nervous system plays a critical role in the pathogenesis of hypertension. The central nervous system (CNS) organizes the sympathetic outflow and various inputs from the periphery. The brain renin-angiotensin system has been studied in various regions involved in controlling sympathetic outflow. Recent progress in cardiovascular research, particularly in vascular biology and neuroscience, as well as in traditional physiological approaches, has advanced the field of the neural control of hypertension in which the CNS plays a vital role. Cardiovascular research relating to hypertension has focused on the roles of nitric oxide, oxidative stress, inflammation, and immunity, and the network among various organs, including the heart, kidney, spleen, gut, and vasculature. The CNS mechanisms are similarly networked with these factors and are widely studied in neuroscience. In this review, I describe the development of the conceptual flow of this network in the field of hypertension on the basis of several important original research articles and discuss potential future breakthroughs leading to clinical precision medicine.
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Affiliation(s)
- Yoshitaka Hirooka
- Department of Medical Technology and Sciences, School of Health Sciences at Fukuoka, International University of Health and Welfare, Okawa City, Fukuoka, Japan
- Department of Cardiovascular Medicine, Hypertension and Heart Failure Center, Takagi Hospital, Okawa City, Fukuoka, Japan
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31
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Tedoldi A, Argent L, Montgomery JM. The role of the tripartite synapse in the heart: how glial cells may contribute to the physiology and pathophysiology of the intracardiac nervous system. Am J Physiol Cell Physiol 2020; 320:C1-C14. [PMID: 33085497 DOI: 10.1152/ajpcell.00363.2020] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
One of the major roles of the intracardiac nervous system (ICNS) is to act as the final site of signal integration for efferent information destined for the myocardium to enable local control of heart rate and rhythm. Multiple subtypes of neurons exist in the ICNS where they are organized into clusters termed ganglionated plexi (GP). The majority of cells in the ICNS are actually glial cells; however, despite this, ICNS glial cells have received little attention to date. In the central nervous system, where glial cell function has been widely studied, glia are no longer viewed simply as supportive cells but rather have been shown to play an active role in modulating neuronal excitability and synaptic plasticity. Pioneering studies have demonstrated that in addition to glia within the brain stem, glial cells within multiple autonomic ganglia in the peripheral nervous system, including the ICNS, can also act to modulate cardiovascular function. Clinically, patients with atrial fibrillation (AF) undergoing catheter ablation show high plasma levels of S100B, a protein produced by cardiac glial cells, correlated with decreased AF recurrence. Interestingly, S100B also alters GP neuron excitability and neurite outgrowth in the ICNS. These studies highlight the importance of understanding how glial cells can affect the heart by modulating GP neuron activity or synaptic inputs. Here, we review studies investigating glia both in the central and peripheral nervous systems to discuss the potential role of glia in controlling cardiac function in health and disease, paying particular attention to the glial cells of the ICNS.
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Affiliation(s)
- Angelo Tedoldi
- Department of Physiology, University of Auckland, Auckland, New Zealand.,Manaaki Mānawa Centre for Heart Research, University of Auckland, Auckland, New Zealand
| | - Liam Argent
- Department of Physiology, University of Auckland, Auckland, New Zealand.,Manaaki Mānawa Centre for Heart Research, University of Auckland, Auckland, New Zealand
| | - Johanna M Montgomery
- Department of Physiology, University of Auckland, Auckland, New Zealand.,Manaaki Mānawa Centre for Heart Research, University of Auckland, Auckland, New Zealand
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32
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Souza MM, Vechiato FMV, Debarba LK, Leao RM, Dias MVS, Pereira AA, Cruz JC, Elias LLK, Antunes-Rodrigues J, Ruginsk SG. Effects of Hyperosmolality on Hypothalamic Astrocytic Area, mRNA Expression and Glutamate Balance In Vitro. Neuroscience 2020; 442:286-295. [PMID: 32599125 DOI: 10.1016/j.neuroscience.2020.06.029] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2019] [Revised: 06/18/2020] [Accepted: 06/19/2020] [Indexed: 11/17/2022]
Abstract
During prolonged dehydration, body fluid homeostasis is challenged by extracellular fluid (ECF) hyperosmolality, which induce important functional changes in the hypothalamus, in parallel with other effector responses, such as the activation of the local renin-angiotensin system (RAS). Therefore, in the present study we investigated the role of sodium-driven ECF hyperosmolality on glial fibrillary acid protein (GFAP) immunoreactivity and protein expression, membrane capacitance, mRNA expression of RAS components and glutamate balance in cultured hypothalamic astrocytes. Our data show that hypothalamic astrocytes respond to increased hyperosmolality with a similar decrease in GFAP expression and membrane capacitance, indicative of reduced cellular area. Hyperosmolality also downregulates the transcript levels of angiotensinogen and both angiotensin-converting enzymes, whereas upregulates type 1a angiotensin II receptor mRNA. Incubation with hypertonic solution also decreases the immunoreactivity to the membrane glutamate/aspartate transporter (GLAST) as well as tritiated-aspartate uptake by astrocytes. This latter effect is completely restored to basal levels when astrocytes previously exposed to hypertonicity are incubated under isotonic conditions. Together with a direct effect on two important local signaling systems (glutamate and RAS), these synaptic rearrangements driven by astrocytes may accomplish for a coordinated increase in the excitatory drive onto the hypothalamic neurosecretory system, ultimately culminating with increased AVP release in response to hyperosmolality.
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Affiliation(s)
- M M Souza
- Department of Physiological Sciences, Biomedical Sciences Institute, Federal University of Alfenas, Alfenas, Minas Gerais, Brazil
| | - F M V Vechiato
- Department of Physiology, School of Medicine of Ribeirao Preto, University of Sao Paulo, Ribeirao Preto, Sao Paulo, Brazil
| | - L K Debarba
- Department of Physiology, School of Medicine of Ribeirao Preto, University of Sao Paulo, Ribeirao Preto, Sao Paulo, Brazil
| | - R M Leao
- Department of Physiology, School of Medicine of Ribeirao Preto, University of Sao Paulo, Ribeirao Preto, Sao Paulo, Brazil
| | - M V S Dias
- Natural Sciences Institute, Federal University of Alfenas, Alfenas, Minas Gerais, Brazil
| | - A A Pereira
- Food and Drugs Department, Pharmaceutical Sciences Faculty, Federal University of Alfenas, Alfenas, Minas Gerais, Brazil
| | - J C Cruz
- Biotechnology Center, Department of Biotechnology, Federal University of Paraiba, Joao Pessoa, Paraiba, Brazil
| | - L L K Elias
- Department of Physiology, School of Medicine of Ribeirao Preto, University of Sao Paulo, Ribeirao Preto, Sao Paulo, Brazil
| | - J Antunes-Rodrigues
- Department of Physiology, School of Medicine of Ribeirao Preto, University of Sao Paulo, Ribeirao Preto, Sao Paulo, Brazil
| | - S G Ruginsk
- Department of Physiological Sciences, Biomedical Sciences Institute, Federal University of Alfenas, Alfenas, Minas Gerais, Brazil.
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Singh P, Dutta SR, Song CY, Oh S, Gonzalez FJ, Malik KU. Brain Testosterone-CYP1B1 (Cytochrome P450 1B1) Generated Metabolite 6β-Hydroxytestosterone Promotes Neurogenic Hypertension and Inflammation. Hypertension 2020; 76:1006-1018. [PMID: 32755412 PMCID: PMC7418933 DOI: 10.1161/hypertensionaha.120.15567] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Supplemental Digital Content is available in the text. Previously, we showed that peripheral administration of 6β-hydroxytestosterone, a CYP1B1 (cytochrome P450 1B1)-generated metabolite of testosterone, promotes angiotensin II-induced hypertension in male mice. However, the site of action and the underlying mechanism by which 6β-hydroxytestosterone contributes to angiotensin II-induced hypertension is not known. Angiotensin II increases blood pressure by its central action, and CYP1B1 is expressed in the brain. This study was conducted to determine whether testosterone-CYP1B1 generated metabolite 6β-hydroxytestosterone locally in the brain promotes the effect of systemic angiotensin II to produce hypertension in male mice. Central CYP1B1 knockdown in wild-type (Cyp1b1+/+) mice by intracerebroventricular-adenovirus-GFP (green fluorescence protein)-CYP1B1-short hairpin (sh)RNA attenuated, whereas reconstitution of CYP1B1 by adenovirus-GFP-CYP1B1-DNA in the paraventricular nucleus but not in subfornical organ in Cyp1b1−/− mice restored angiotensin II-induced increase in systolic blood pressure measured by tail-cuff. Intracerebroventricular-testosterone in orchidectomized (Orchi)-Cyp1b1+/+ but not in Orchi-Cyp1b1−/−, and intracerebroventricular-6β-hydroxytestosterone in the Orchi-Cyp1b1−/− mice restored the angiotensin II-induced: (1) increase in mean arterial pressure measured by radiotelemetry, and autonomic imbalance; (2) reactive oxygen species production in the subfornical organ and paraventricular nucleus; (3) activation of microglia and astrocyte, and neuroinflammation in the paraventricular nucleus. The effect of intracerebroventricular-6β-hydroxytestosterone to restore the angiotensin II-induced increase in mean arterial pressure and autonomic imbalance in Orchi-Cyp1b1−/− mice was inhibited by intracerebroventricular-small interfering (si)RNA-androgen receptor (AR) and GPRC6A (G protein-coupled receptor C6A). These data suggest that testosterone-CYP1B1-generated metabolite 6β-hydroxytestosterone, most likely in the paraventricular nucleus via AR and GPRC6A, contributes to angiotensin II-induced hypertension and neuroinflammation in male mice.
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Affiliation(s)
- Purnima Singh
- From the Department of Pharmacology, Addiction Science, and Toxicology, College of Medicine, University of Tennessee Health Science Center, Memphis (P.S., S.R.D., C.Y.S.)
| | - Shubha Ranjan Dutta
- From the Department of Pharmacology, Addiction Science, and Toxicology, College of Medicine, University of Tennessee Health Science Center, Memphis (P.S., S.R.D., C.Y.S.)
| | - Chi Young Song
- From the Department of Pharmacology, Addiction Science, and Toxicology, College of Medicine, University of Tennessee Health Science Center, Memphis (P.S., S.R.D., C.Y.S.)
| | | | - Frank J Gonzalez
- Laboratory of Metabolism, National Cancer Institute, Bethesda, MD (F.J.G.)
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Elsaafien K, de Kloet AD, Krause EG, Sumners C. Brain Angiotensin Type-1 and Type-2 Receptors in Physiological and Hypertensive Conditions: Focus on Neuroinflammation. Curr Hypertens Rep 2020; 22:48. [PMID: 32661792 PMCID: PMC7780348 DOI: 10.1007/s11906-020-01062-0] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
PURPOSE OF REVIEW To review recent data that suggest opposing effects of brain angiotensin type-1 (AT1R) and type-2 (AT2R) receptors on blood pressure (BP). Here, we discuss recent studies that suggest pro-hypertensive and pro-inflammatory actions of AT1R and anti-hypertensive and anti-inflammatory actions of AT2R. Further, we propose mechanisms for the interplay between brain angiotensin receptors and neuroinflammation in hypertension. RECENT FINDINGS The renin-angiotensin system (RAS) plays an important role in regulating cardiovascular physiology. This includes brain AT1R and AT2R, both of which are expressed in or adjacent to brain regions that control BP. Activation of AT1R within those brain regions mediate increases in BP and cause neuroinflammation, which augments the BP increase in hypertension. The fact that AT1R and AT2R have opposing actions on BP suggests that AT1R and AT2R may have similar opposing actions on neuroinflammation. However, the mechanisms by which brain AT1R and AT2R mediate neuroinflammatory responses remain unclear. The interplay between brain angiotensin receptor subtypes and neuroinflammation exacerbates or protects against hypertension.
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Affiliation(s)
- Khalid Elsaafien
- Department of Pharmacodynamics, University of Florida College of Pharmacy, Gainesville, FL, USA
| | - Annette D de Kloet
- Department of Physiology and Functional Genomics, College of Medicine, University of Florida, Gainesville, FL, USA
- Center for Integrative Cardiovascular and Metabolic Diseases, University of Florida, Gainesville, FL, USA
- Evelyn F. and William L. McKnight Brain Institute, University of Florida, Gainesville, FL, USA
| | - Eric G Krause
- Department of Pharmacodynamics, University of Florida College of Pharmacy, Gainesville, FL, USA
- Center for Integrative Cardiovascular and Metabolic Diseases, University of Florida, Gainesville, FL, USA
- Evelyn F. and William L. McKnight Brain Institute, University of Florida, Gainesville, FL, USA
| | - Colin Sumners
- Department of Physiology and Functional Genomics, College of Medicine, University of Florida, Gainesville, FL, USA.
- Center for Integrative Cardiovascular and Metabolic Diseases, University of Florida, Gainesville, FL, USA.
- Evelyn F. and William L. McKnight Brain Institute, University of Florida, Gainesville, FL, USA.
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Shi Z, Pelletier NE, Wong J, Li B, Sdrulla AD, Madden CJ, Marks DL, Brooks VL. Leptin increases sympathetic nerve activity via induction of its own receptor in the paraventricular nucleus. eLife 2020; 9:e55357. [PMID: 32538782 PMCID: PMC7316512 DOI: 10.7554/elife.55357] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2020] [Accepted: 06/12/2020] [Indexed: 12/11/2022] Open
Abstract
Whether leptin acts in the paraventricular nucleus (PVN) to increase sympathetic nerve activity (SNA) is unclear, since PVN leptin receptors (LepR) are sparse. We show in rats that PVN leptin slowly increases SNA to muscle and brown adipose tissue, because it induces the expression of its own receptor and synergizes with local glutamatergic neurons. PVN LepR are not expressed in astroglia and rarely in microglia; instead, glutamatergic neurons express LepR, some of which project to a key presympathetic hub, the rostral ventrolateral medulla (RVLM). In PVN slices from mice expressing GCaMP6, leptin excites glutamatergic neurons. LepR are expressed mainly in thyrotropin-releasing hormone (TRH) neurons, some of which project to the RVLM. Injections of TRH into the RVLM and dorsomedial hypothalamus increase SNA, highlighting these nuclei as likely targets. We suggest that this neuropathway becomes important in obesity, in which elevated leptin maintains the hypothalamic pituitary thyroid axis, despite leptin resistance.
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Affiliation(s)
- Zhigang Shi
- Department of Physiology and PharmacologyPortlandUnited States
| | | | - Jennifer Wong
- Department of Physiology and PharmacologyPortlandUnited States
| | - Baoxin Li
- Department of Physiology and PharmacologyPortlandUnited States
| | - Andrei D Sdrulla
- Department of Anesthesiology and Perioperative MedicinePortlandUnited States
| | | | - Daniel L Marks
- Department of Pediatrics, Pape Family Pediatric Research Institute, Brenden-Colson Center for Pancreatic Care Oregon Health & Science UniversityPortlandUnited States
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Li Y, Yu R, Zhang D, Yang W, Hou Q, Li Y, Jiang H. Deciphering the Mechanism of the Anti-Hypertensive Effect of Isorhynchophylline by Targeting Neurotransmitters Metabolism of Hypothalamus in Spontaneously Hypertensive Rats. ACS Chem Neurosci 2020; 11:1563-1572. [PMID: 32356970 DOI: 10.1021/acschemneuro.9b00699] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
Essential hypertension is a major risk factor for cardiovascular disease that can lead eventually to structural and functional alterations in the brain. Accumulating evidence has suggested that the increased activities in renin-angiotensin system and sympathetic nerve participated in the pathogenesis of hypertension that is related to the imbalance between neurotransmitters. The potential role in essential hypertension arising from alterations of neurotransmitters in the central nervous system remains understudied. Isorhynchophylline is a major oxindole alkaloid extracted from Uncaria rhynchophylla, which has been widely used for treating hypertension and neurodegenerative diseases. Whether isorhynchophylline acts on neurotransmitters to lower blood pressure has been hypothesized but rarely demonstrated unequivocally. Here, we studied the metabolic neurotransmitter profiles in the hypothalamus using a targeted metabolomic approach in spontaneously hypertensive rats after isorhynchophylline intervention. Our study demonstrated that isorhynchophylline exhibited a strong anti-hypertensive effect in spontaneously hypertensive rats by improving the neurotransmitter imbalance in the hypothalamus and inhibiting the overactivation of the renin-angiotensin system and sympathetic nerve system. Overall, this study played an essential role in enhancing our understanding of the mechanism of isorhynchophylline in essential hypertension and in providing theoretical evidence for future research and clinical application.
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Affiliation(s)
- Yuan Li
- Experimental Center, Shandong University of Traditional Chinese Medicine, Jinan 250355, Shandong, China
- Key Laboratory of Traditional Chinese Medicine Classical Theory, Ministry of Education, Shandong University of Traditional Chinese Medicine, Jinan 250355, Shandong, China
- Shandong Provincial Key Laboratory of Traditional Chinese Medicine for Basic Research, Shandong University of Traditional Chinese Medicine, Jinan 250355, Shandong, China
| | - Ruixue Yu
- College of Pharmaceutical Sciences, Shandong University of Traditional Chinese Medicine, Jinan 250355, Shandong China
| | - Dan Zhang
- Experimental Center, Shandong University of Traditional Chinese Medicine, Jinan 250355, Shandong, China
- Key Laboratory of Traditional Chinese Medicine Classical Theory, Ministry of Education, Shandong University of Traditional Chinese Medicine, Jinan 250355, Shandong, China
- Shandong Provincial Key Laboratory of Traditional Chinese Medicine for Basic Research, Shandong University of Traditional Chinese Medicine, Jinan 250355, Shandong, China
| | - Wenqing Yang
- Experimental Center, Shandong University of Traditional Chinese Medicine, Jinan 250355, Shandong, China
- Key Laboratory of Traditional Chinese Medicine Classical Theory, Ministry of Education, Shandong University of Traditional Chinese Medicine, Jinan 250355, Shandong, China
- Shandong Provincial Key Laboratory of Traditional Chinese Medicine for Basic Research, Shandong University of Traditional Chinese Medicine, Jinan 250355, Shandong, China
| | - Qingqing Hou
- College of Pharmaceutical Sciences, Shandong University of Traditional Chinese Medicine, Jinan 250355, Shandong China
| | - Yunlun Li
- Experimental Center, Shandong University of Traditional Chinese Medicine, Jinan 250355, Shandong, China
- Traditional Chinese Medicine Clinical Research Base for Hypertension, Affiliated Hospital of Shandong University of Traditional Chinese Medicine, Jinan 250011, Shandong, China
| | - Haiqiang Jiang
- Experimental Center, Shandong University of Traditional Chinese Medicine, Jinan 250355, Shandong, China
- Key Laboratory of Traditional Chinese Medicine Classical Theory, Ministry of Education, Shandong University of Traditional Chinese Medicine, Jinan 250355, Shandong, China
- Shandong Provincial Key Laboratory of Traditional Chinese Medicine for Basic Research, Shandong University of Traditional Chinese Medicine, Jinan 250355, Shandong, China
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Chen J, Yin D, He X, Gao M, Choi Y, Luo G, Wang H, Qu X. Modulation of activated astrocytes in the hypothalamus paraventricular nucleus to prevent ventricular arrhythmia complicating acute myocardial infarction. Int J Cardiol 2020; 308:33-41. [DOI: 10.1016/j.ijcard.2020.01.035] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/23/2019] [Revised: 01/06/2020] [Accepted: 01/15/2020] [Indexed: 02/06/2023]
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38
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Dupont AG, Légat L. GABA is a mediator of brain AT 1 and AT 2 receptor-mediated blood pressure responses. Hypertens Res 2020; 43:995-1005. [PMID: 32451494 DOI: 10.1038/s41440-020-0470-9] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2019] [Revised: 03/24/2020] [Accepted: 04/01/2020] [Indexed: 02/07/2023]
Abstract
The nucleus tractus solitarius (NTS), paraventricular nucleus (PVN), and rostral ventrolateral medulla (RVLM) are the most targeted regions of central blood pressure control studies. Glutamate and gamma-aminobutyric acid (GABA) interact within these brain regions to modulate blood pressure. The brain renin-angiotensin system also participates in central blood pressure control. Angiotensin II increases blood pressure through the stimulation of angiotensin II type 1 (AT1) receptors within the PVN and RVLM and attenuates baroreceptor sensitivity, resulting in elevated blood pressure within the NTS. Angiotensin II type 2 (AT2) receptors in cardiovascular control centers in the brain also appear to be involved in blood pressure control and counteract AT1 receptor-mediated effects. The current review is focused on the interaction of GABA with AT1 and AT2 receptors in the control of blood pressure within the RVLM, PVN and NTS. Within the NTS, GABA is released from local GABAergic interneurons that are stimulated by local AT1 receptors and mediates a hypertensive response. In contrast, the local increase in GABA levels observed after AT2 receptor stimulation within the RVLM, likely from GABAergic nerve endings originating in the caudal ventrolateral medulla, is important in the mediation of the hypotensive response. Preliminary results suggest that the hypertensive response to AT1 receptor stimulation within the RVLM is associated with a reduction in GABA release. The current experimental evidence therefore indicates that GABA is an important mediator of brainstem responses to AT1 and AT2 receptor stimulation and that increased GABA release may play a role in hypertensive and hypotensive responses, depending on the site of action.
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Affiliation(s)
- Alain G Dupont
- Department of Pharmacology, Research Group Experimental Pharmacology (EFAR), Center for Neurosciences, (C4N) Vrije Universiteit Brussel, Laarbeeklaan 103, Brussels, 1090, Belgium
| | - Laura Légat
- Department of Pharmacology, Research Group Experimental Pharmacology (EFAR), Center for Neurosciences, (C4N) Vrije Universiteit Brussel, Laarbeeklaan 103, Brussels, 1090, Belgium.
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Japundžić-Žigon N, Lozić M, Šarenac O, Murphy D. Vasopressin & Oxytocin in Control of the Cardiovascular System: An Updated Review. Curr Neuropharmacol 2020; 18:14-33. [PMID: 31544693 PMCID: PMC7327933 DOI: 10.2174/1570159x17666190717150501] [Citation(s) in RCA: 25] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2019] [Revised: 06/03/2019] [Accepted: 07/06/2019] [Indexed: 01/19/2023] Open
Abstract
Since the discovery of vasopressin (VP) and oxytocin (OT) in 1953, considerable knowledge has been gathered about their roles in cardiovascular homeostasis. Unraveling VP vasoconstrictor properties and V1a receptors in blood vessels generated powerful hemostatic drugs and drugs effective in the treatment of certain forms of circulatory collapse (shock). Recognition of the key role of VP in water balance via renal V2 receptors gave birth to aquaretic drugs found to be useful in advanced stages of congestive heart failure. There are still unexplored actions of VP and OT on the cardiovascular system, both at the periphery and in the brain that may open new venues in treatment of cardiovascular diseases. After a brief overview on VP, OT and their peripheral action on the cardiovascular system, this review focuses on newly discovered hypothalamic mechanisms involved in neurogenic control of the circulation in stress and disease.
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Affiliation(s)
| | - Maja Lozić
- Faculty of Medicine, University of Belgrade, Belgrade, Serbia
| | - Olivera Šarenac
- Faculty of Medicine, University of Belgrade, Belgrade, Serbia
| | - David Murphy
- School of Clinical Sciences, University of Bristol, Bristol, United Kingdom
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40
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Blood-brain barrier dysfunction: the undervalued frontier of hypertension. J Hum Hypertens 2020; 34:682-691. [PMID: 32424144 DOI: 10.1038/s41371-020-0352-2] [Citation(s) in RCA: 26] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2019] [Revised: 04/29/2020] [Accepted: 05/01/2020] [Indexed: 02/06/2023]
Abstract
The blood-brain barrier (BBB) constitutes the complex anatomic and physiologic interface between the intravascular compartment and the central nervous system, and its integrity is paramount for the maintenance of the very sensitive homeostasis of the central nervous system. Arterial hypertension is a leading cause of morbidity and mortality. The BBB has been shown to be disrupted in essential hypertension. BBB integrity is important for central autonomic control and this may be implicated in the pathophysiology of hypertension. On the other hand, evidence from experimental studies indicates that BBB disruption can be present in both hypertensive disease and dementia syndromes, suggesting a possibly key position of loss of BBB integrity in the pathophysiological pathways linking arterial hypertension with cognitive decline. Although much still remains to be elucidated with respect to the exact underlying mechanisms, the discovery of novel pathological pathways has changed our understanding of adult dementia and central nervous system disease overall, pointing out-in parallel-new potential therapeutic targets. The aim of this review is to summarize current scientific knowledge relevant to the pathophysiologic pathways that are involved in the disruption of the BBB function and potentially mediate hypertension-induced cognitive impairment. In parallel, we underline the differential cognition-preserving effect of several antihypertensive agents of similar blood pressure-lowering capacity, highlighting the presence of previously under-recognized BBB-protective actions of these drugs.
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41
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Singh P, Song CY, Dutta SR, Gonzalez FJ, Malik KU. Central CYP1B1 (Cytochrome P450 1B1)-Estradiol Metabolite 2-Methoxyestradiol Protects From Hypertension and Neuroinflammation in Female Mice. Hypertension 2020; 75:1054-1062. [PMID: 32148125 PMCID: PMC7098446 DOI: 10.1161/hypertensionaha.119.14548] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
Supplemental Digital Content is available in the text. Previously, we showed that peripheral administration of 2-ME (2-methoxyestradiol), a CYP1B1 (cytochrome P450 1B1)-catechol-O-methyltransferase (COMT) generated metabolite of E2 (17β-Estradiol), protects against angiotensin II-induced hypertension in female mice. The demonstration that central E2 inhibits angiotensin II-induced hypertension, together with the expression of CYP1B1 in the brain, led us to hypothesize that E2-CYP1B1 generated metabolite 2-ME in the brain mediates its protective action against angiotensin II-induced hypertension in female mice. To test this hypothesis, we examined the effect of intracerebroventricularly (ICV) administered E2 in ovariectomized (OVX)-wild-type (Cyp1b1+/+) and OVX-Cyp1b1−/− mice on the action of systemic angiotensin II. ICV-E2 attenuated the angiotensin II-induced increase in mean arterial blood pressure, impairment of baroreflex sensitivity, and sympathetic activity in OVX-Cyp1b1+/+ but not in ICV-injected short interfering (si)RNA-COMT or OVX-Cyp1b1−/− mice. ICV-2-ME attenuated the angiotensin II-induced increase in blood pressure in OVX-Cyp1b1−/− mice; this effect was inhibited by ICV-siRNA estrogen receptor-α (ERα) and G protein-coupled estrogen receptor 1 (GPER1). ICV-E2 in OVX-Cyp1b1+/+ but not in OVX-Cyp1b1−/− mice and 2-ME in the OVX-Cyp1b1−/− inhibited angiotensin II-induced increase in reactive oxygen species production in the subfornical organ and paraventricular nucleus, activation of microglia and astrocyte, and neuroinflammation in paraventricular nucleus. Furthermore, central CYP1B1 gene disruption in Cyp1b1+/+ mice by ICV-adenovirus-GFP (green fluorescence protein)-CYP1B1-short hairpin (sh)RNA elevated, while reconstitution by adenovirus-GFP-CYP1B1-DNA in the paraventricular nucleus but not in subfornical organ in Cyp1b1−/− mice attenuated the angiotensin II-induced increase in systolic blood pressure. These data suggest that E2-CYP1B1-COMT generated metabolite 2-ME, most likely in the paraventricular nucleus via estrogen receptor-α and GPER1, protects against angiotensin II-induced hypertension and neuroinflammation in female mice.
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Affiliation(s)
- Purnima Singh
- From the Department of Pharmacology, Addiction Science, and Toxicology, College of Medicine, University of Tennessee Health Science Center, Memphis (P.S., C.Y.S., S.R.D., K.U.M.)
| | - Chi Young Song
- From the Department of Pharmacology, Addiction Science, and Toxicology, College of Medicine, University of Tennessee Health Science Center, Memphis (P.S., C.Y.S., S.R.D., K.U.M.)
| | - Shubha Ranjan Dutta
- From the Department of Pharmacology, Addiction Science, and Toxicology, College of Medicine, University of Tennessee Health Science Center, Memphis (P.S., C.Y.S., S.R.D., K.U.M.)
| | - Frank J Gonzalez
- Laboratory of Metabolism, National Cancer Institute, Bethesda, MD (F.J.G.)
| | - Kafait U Malik
- From the Department of Pharmacology, Addiction Science, and Toxicology, College of Medicine, University of Tennessee Health Science Center, Memphis (P.S., C.Y.S., S.R.D., K.U.M.)
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42
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Donertas Ayaz B, Zubcevic J. Gut microbiota and neuroinflammation in pathogenesis of hypertension: A potential role for hydrogen sulfide. Pharmacol Res 2020; 153:104677. [PMID: 32023431 PMCID: PMC7056572 DOI: 10.1016/j.phrs.2020.104677] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/07/2019] [Revised: 11/27/2019] [Accepted: 01/27/2020] [Indexed: 02/06/2023]
Abstract
Inflammation and gut dysbiosis are hallmarks of hypertension (HTN). Hydrogen sulfide (H2S) is an important freely diffusing molecule that modulates the function of neural, cardiovascular and immune systems, and circulating levels of H2S are reduced in animals and humans with HTN. While most research to date has focused on H₂S produced endogenously by the host, H2S is also produced by the gut bacteria and may affect the host homeostasis. Here, we review an association between neuroinflammation and gut dysbiosis in HTN, with special emphasis on a potential role of H2S in this interplay.
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Affiliation(s)
- Basak Donertas Ayaz
- Department of Physiological Sciences, College of Veterinary Medicine, University of Florida, Gainesville, FL, United States; Department of Pharmacology, College of Medicine, University of Eskisehir Osmangazi, Eskisehir, Turkey
| | - Jasenka Zubcevic
- Department of Physiological Sciences, College of Veterinary Medicine, University of Florida, Gainesville, FL, United States.
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43
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Sumners C, Alleyne A, Rodríguez V, Pioquinto DJ, Ludin JA, Kar S, Winder Z, Ortiz Y, Liu M, Krause EG, de Kloet AD. Brain angiotensin type-1 and type-2 receptors: cellular locations under normal and hypertensive conditions. Hypertens Res 2019; 43:281-295. [PMID: 31853042 DOI: 10.1038/s41440-019-0374-8] [Citation(s) in RCA: 27] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2019] [Revised: 10/25/2019] [Accepted: 11/02/2019] [Indexed: 12/15/2022]
Abstract
Brain angiotensin-II (Ang-II) type-1 receptors (AT1Rs), which exert profound effects on normal cardiovascular, fluid, and metabolic homeostasis, are overactivated in and contribute to chronic sympathoexcitation and hypertension. Accumulating evidence indicates that the activation of Ang-II type-2 receptors (AT2Rs) in the brain exerts effects that are opposite to those of AT1Rs, lowering blood pressure, and reducing hypertension. Thus, it would be interesting to understand the relative cellular localization of AT1R and AT2R in the brain under normal conditions and whether this localization changes during hypertension. Here, we developed a novel AT1aR-tdTomato reporter mouse strain in which the location of brain AT1aR was largely consistent with that determined in the previous studies. This AT1aR-tdTomato reporter mouse strain was crossed with our previously described AT2R-eGFP reporter mouse strain to yield a novel dual AT1aR/AT2R reporter mouse strain, which allowed us to determine that AT1aR and AT2R are primarily localized to different populations of neurons in brain regions controlling cardiovascular, fluid, and metabolic homeostasis. Using the individual AT1aR-tdTomato reporter mice, we also demonstrated that during hypertension induced by the administration of deoxycorticosterone acetate-salt, there was no shift in the expression of AT1aR from neurons to microglia or astrocytes in the paraventricular nucleus, a brain area important for sympathetic regulation. Using AT2R-eGFP reporter mice under similar hypertensive conditions, we demonstrated that the same was true of AT2R expression in the nucleus of the solitary tract (NTS), an area critical for baroreflex control. Collectively, these findings provided a novel means to assess the colocalization of AT1R and AT2R in the brain and a novel view of their cellular localization in hypertension.
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Affiliation(s)
- Colin Sumners
- Department of Physiology and Functional Genomics, College of Medicine, University of Florida, Gainesville, FL, 32611, USA
| | - Amy Alleyne
- Department of Pharmacodynamics, College of Pharmacy, University of Florida, Gainesville, FL, 32611, USA
| | - Vermalí Rodríguez
- Department of Physiology and Functional Genomics, College of Medicine, University of Florida, Gainesville, FL, 32611, USA
| | - David J Pioquinto
- Department of Pharmacodynamics, College of Pharmacy, University of Florida, Gainesville, FL, 32611, USA
| | - Jacob A Ludin
- Department of Pharmacodynamics, College of Pharmacy, University of Florida, Gainesville, FL, 32611, USA
| | - Shormista Kar
- Department of Physiology and Functional Genomics, College of Medicine, University of Florida, Gainesville, FL, 32611, USA
| | - Zachary Winder
- Department of Physiology and Functional Genomics, College of Medicine, University of Florida, Gainesville, FL, 32611, USA.,Department of Pharmacodynamics, College of Pharmacy, University of Florida, Gainesville, FL, 32611, USA
| | - Yuma Ortiz
- Department of Pharmacodynamics, College of Pharmacy, University of Florida, Gainesville, FL, 32611, USA
| | - Meng Liu
- Department of Physiology and Functional Genomics, College of Medicine, University of Florida, Gainesville, FL, 32611, USA
| | - Eric G Krause
- Department of Pharmacodynamics, College of Pharmacy, University of Florida, Gainesville, FL, 32611, USA
| | - Annette D de Kloet
- Department of Physiology and Functional Genomics, College of Medicine, University of Florida, Gainesville, FL, 32611, USA.
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Xu J, Molinas AJR, Mukerjee S, Morgan DA, Rahmouni K, Zsombok A, Lazartigues E. Activation of ADAM17 (A Disintegrin and Metalloprotease 17) on Glutamatergic Neurons Selectively Promotes Sympathoexcitation. Hypertension 2019; 73:1266-1274. [PMID: 31006330 DOI: 10.1161/hypertensionaha.119.12832] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Chronic activation of the brain renin-angiotensin system contributes to the development of hypertension by altering autonomic balance. Beyond the essential role of Ang II (angiotensin II) type 1 receptors, ADAM17 (A disintegrin and metalloprotease 17) is also found to promote brain renin-angiotensin system overactivation. ADAM17 is robustly expressed in various cell types within the central nervous system. The aim of this study was to determine whether ADAM17 modulates presympathetic neuronal activity to promote autonomic dysregulation in salt-sensitive hypertension. To test our hypothesis, ADAM17 was selectively knocked down in glutamatergic neurons using Cre-loxP technology. In mice lacking ADAM17 in glutamatergic neurons, the blood pressure increase induced by deoxycorticosterone acetate-salt treatment was blunted. Deoxycorticosterone acetate-salt significantly elevated cardiac and vascular sympathetic drive in control mice, while such effects were reduced in mice with ADAM17 knockdown. This blunted sympathoexcitation was extended to the spleen, with a lesser activation of the peripheral immune system, translating into a sequestration of circulating T cells within this organ, compared with controls. Within the paraventricular nucleus, Ang II-induced activation of kidney-related presympathetic glutamatergic neurons was reduced in ADAM17 knockdown mice, with the majority of cells no longer responding to Ang II stimulation, confirming the supportive role of ADAM17 in increasing presympathetic neuronal activity. Overall, our data highlight the pivotal role of neuronal ADAM17 in regulating sympathetic activity and demonstrate that activation of ADAM17 in glutamatergic neurons leads to a selective increase of sympathetic output, but not vagal tone, to specific organs, ultimately contributing to dysautonomia and salt-sensitive hypertension.
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Affiliation(s)
- Jiaxi Xu
- From the Department of Pharmacology and Experimental Therapeutics (J.X., S.M., E.L.), Louisiana State University Health Sciences Center, New Orleans.,Cardiovascular Center of Excellence (J.X., S.M., E.L.), Louisiana State University Health Sciences Center, New Orleans.,Neuroscience Center of Excellence (J.X., S.M., E.L.), Louisiana State University Health Sciences Center, New Orleans.,Research and Development, SouthEast Louisiana Veterans Health Care System, New Orleans (J.X., E.L.)
| | - Adrien J R Molinas
- Department of Physiology, Tulane University, New Orleans, LA (A.J.R.M., A.Z.)
| | - Snigdha Mukerjee
- From the Department of Pharmacology and Experimental Therapeutics (J.X., S.M., E.L.), Louisiana State University Health Sciences Center, New Orleans.,Cardiovascular Center of Excellence (J.X., S.M., E.L.), Louisiana State University Health Sciences Center, New Orleans.,Neuroscience Center of Excellence (J.X., S.M., E.L.), Louisiana State University Health Sciences Center, New Orleans
| | - Donald A Morgan
- Department of Pharmacology, University of Iowa, Iowa City, IA (D.A.M., K.R.)
| | - Kamal Rahmouni
- Department of Pharmacology, University of Iowa, Iowa City, IA (D.A.M., K.R.)
| | - Andrea Zsombok
- Department of Physiology, Tulane University, New Orleans, LA (A.J.R.M., A.Z.)
| | - Eric Lazartigues
- From the Department of Pharmacology and Experimental Therapeutics (J.X., S.M., E.L.), Louisiana State University Health Sciences Center, New Orleans.,Cardiovascular Center of Excellence (J.X., S.M., E.L.), Louisiana State University Health Sciences Center, New Orleans.,Neuroscience Center of Excellence (J.X., S.M., E.L.), Louisiana State University Health Sciences Center, New Orleans.,Research and Development, SouthEast Louisiana Veterans Health Care System, New Orleans (J.X., E.L.)
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Yang T, Rodriguez V, Malphurs WL, Schmidt JT, Ahmari N, Sumners C, Martyniuk CJ, Zubcevic J. Butyrate regulates inflammatory cytokine expression without affecting oxidative respiration in primary astrocytes from spontaneously hypertensive rats. Physiol Rep 2019; 6:e13732. [PMID: 30039527 PMCID: PMC6056753 DOI: 10.14814/phy2.13732] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2018] [Revised: 05/07/2018] [Accepted: 05/09/2018] [Indexed: 01/16/2023] Open
Abstract
Neurons and glia exhibit metabolic imbalances in hypertensive animal models, and loss of metabolic homeostasis can lead to neuroinflammation and oxidative stress. The objective of this study was to determine the effects of the microbial metabolite butyrate on mitochondrial bioenergetics and inflammatory markers in mixed brainstem and hypothalamic primary cultures of astrocytes between normotensive (Sprague-Dawley, S-D) and spontaneously hypertensive (SHR) rats. Bioenergetics of mitochondria in astrocytes from normotensive S-D rats were modified with butyrate, but this was not the case in astrocytes derived from SHR, suggesting aberrant mitochondrial function. Transcripts related to oxidative stress, butyrate transporters, butyrate metabolism, and neuroinflammation were quantified in astrocyte cultures treated with butyrate at 0, 200, 600, and 1000 μmol/L. Butyrate decreased catalase and monocarboxylate transporter 1 mRNA in astrocytes of S-D rats but not in the SHR. Moreover, while butyrate did not directly regulate the expression of 3-hydroxybutyrate dehydrogenase 1 and 2 in astrocytes of either strain, the expression levels for these transcripts in untreated cultures were lower in the SHR compared to S-D. We observed higher levels of specific inflammatory cytokines in astrocytes of SHR, and treatment with butyrate decreased expression of Ccl2 and Tlr4 in SHR astrocytes only. Conversely, butyrate treatment increased expression of tumor necrosis factor in astrocytes from SHR but not from the S-D rats. This study improves our understanding of the role of microbial metabolites in regulating astrocyte function, and provides support that butyrate differentially regulates both the bioenergetics and transcripts related to neuroinflammation in astrocytes from SHR versus S-D rats.
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Affiliation(s)
- Tao Yang
- Department of Physiological Sciences, College of Veterinary Medicine, University of Florida, Gainesville, Florida
| | - Vermali Rodriguez
- Department of Physiology and Functional Genomics, College of Medicine, University of Florida, Gainesville, Florida
| | - Wendi L Malphurs
- Department of Physiological Sciences, College of Veterinary Medicine, University of Florida, Gainesville, Florida
| | - Jordan T Schmidt
- Department of Physiological Sciences and Center for Environmental and Human Toxicology, University of Florida Genetics Institute, Interdisciplinary Program in Biomedical Sciences Neuroscience, College of Veterinary Medicine, University of Florida, Gainesville, Florida
| | - Niousha Ahmari
- Department of Physiological Sciences, College of Veterinary Medicine, University of Florida, Gainesville, Florida
| | - Colin Sumners
- Department of Physiology and Functional Genomics, College of Medicine, University of Florida, Gainesville, Florida
| | - Christopher J Martyniuk
- Department of Physiological Sciences and Center for Environmental and Human Toxicology, University of Florida Genetics Institute, Interdisciplinary Program in Biomedical Sciences Neuroscience, College of Veterinary Medicine, University of Florida, Gainesville, Florida
| | - Jasenka Zubcevic
- Department of Physiological Sciences, College of Veterinary Medicine, University of Florida, Gainesville, Florida
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Phipps JA, Dixon MA, Jobling AI, Wang AY, Greferath U, Vessey KA, Fletcher EL. The renin-angiotensin system and the retinal neurovascular unit: A role in vascular regulation and disease. Exp Eye Res 2019; 187:107753. [PMID: 31408629 DOI: 10.1016/j.exer.2019.107753] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2019] [Revised: 07/31/2019] [Accepted: 08/05/2019] [Indexed: 01/16/2023]
Abstract
The retina is known to have a local renin-angiotensin system (RAS) and dysfunction in the RAS is often associated with diseases of the retinal vasculature that cause irreversible vision loss. Regulation of the retinal vasculature to meet the metabolic needs of the tissues occurs through a mechanism called neurovascular coupling, which is critical for maintaining homeostatic function and support for neurons. Neurovascular coupling is the process by which support cells, including glia, regulate blood vessel calibre and blood flow in response to neural activity. In retinal vascular diseases, this coupling mechanism is often disrupted. However, the role that angiotensin II (Ang II), the main effector peptide of the RAS, has in regulating both the retinal vasculature and neurovascular coupling is not fully understood. As components of the RAS are located on the principal neurons, glia and blood vessels of the retina, it is possible that Ang II has a role in regulating communication and function between these three cell types, and therefore the capacity to regulate neurovascular coupling. This review focuses on components of the RAS located on the retinal neurovascular unit, and the potential of this system to contribute to blood flow modulation in the healthy and compromised retina.
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Affiliation(s)
- Joanna A Phipps
- Department of Anatomy and Neuroscience, The University of Melbourne, Parkville, 3010, Victoria, Australia
| | - Michael A Dixon
- Department of Anatomy and Neuroscience, The University of Melbourne, Parkville, 3010, Victoria, Australia
| | - Andrew I Jobling
- Department of Anatomy and Neuroscience, The University of Melbourne, Parkville, 3010, Victoria, Australia
| | - Anna Y Wang
- Department of Anatomy and Neuroscience, The University of Melbourne, Parkville, 3010, Victoria, Australia
| | - Ursula Greferath
- Department of Anatomy and Neuroscience, The University of Melbourne, Parkville, 3010, Victoria, Australia
| | - Kirstan A Vessey
- Department of Anatomy and Neuroscience, The University of Melbourne, Parkville, 3010, Victoria, Australia
| | - Erica L Fletcher
- Department of Anatomy and Neuroscience, The University of Melbourne, Parkville, 3010, Victoria, Australia.
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47
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Zubcevic J, Richards EM, Yang T, Kim S, Sumners C, Pepine CJ, Raizada MK. Impaired Autonomic Nervous System-Microbiome Circuit in Hypertension. Circ Res 2019; 125:104-116. [PMID: 31219753 PMCID: PMC6588177 DOI: 10.1161/circresaha.119.313965] [Citation(s) in RCA: 69] [Impact Index Per Article: 13.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Hypertension affects an estimated 103 million Americans, yet gaps in knowledge continue to limit its successful management. Rapidly emerging evidence is linking gut dysbiosis to many disorders and diseases including hypertension. The evolution of the -omics techniques has allowed determination of the abundance and potential function of gut bacterial species by next-generation bacterial sequencing, whereas metabolomics techniques report shifts in bacterial metabolites in the systemic circulation of hypertensive patients and rodent models of hypertension. The gut microbiome and host have evolved to exist in balance and cooperation, and there is extensive crosstalk between the 2 to maintain this balance, including during regulation of blood pressure. However, an understanding of the mechanisms of dysfunctional host-microbiome interactions in hypertension is still lacking. Here, we synthesize some of our recent data with published reports and present concepts and a rationale for our emerging hypothesis of a dysfunctional gut-brain axis in hypertension. Hopefully, this new information will improve the understanding of hypertension and help to address some of these knowledge gaps.
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Affiliation(s)
- Jasenka Zubcevic
- Department of Physiological Sciences, College of Veterinary Medicine; University of Florida, Gainesville FL32610
| | - Elaine M. Richards
- Department of Physiology and Functional Genomics, College of Medicine, University of Florida, Gainesville FL32610
| | - Tao Yang
- Department of Physiology and Functional Genomics, College of Medicine, University of Florida, Gainesville FL32610
| | - Seungbum Kim
- Department of Physiology and Functional Genomics, College of Medicine, University of Florida, Gainesville FL32610
| | - Colin Sumners
- Department of Physiology and Functional Genomics, College of Medicine, University of Florida, Gainesville FL32610
| | - Carl J Pepine
- Division of Cardiovascular Medicine, Department of Medicine, College of Medicine, University of Florida, Gainesville FL32610
| | - Mohan K Raizada
- Department of Physiology and Functional Genomics, College of Medicine, University of Florida, Gainesville FL32610
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48
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Chowen JA, Frago LM, Fernández-Alfonso MS. Physiological and pathophysiological roles of hypothalamic astrocytes in metabolism. J Neuroendocrinol 2019; 31:e12671. [PMID: 30561077 DOI: 10.1111/jne.12671] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/15/2018] [Revised: 11/27/2018] [Accepted: 12/11/2018] [Indexed: 12/26/2022]
Abstract
The role of glial cells, including astrocytes, in metabolic control has received increasing attention in recent years. Although the original interest in these macroglial cells was a result of astrogliosis being observed in the hypothalamus of diet-induced obese subjects, studies have also focused on how they participate in the physiological control of appetite and energy expenditure. Astrocytes express receptors for numerous hormones, growth factors and neuropeptides. Some functions of astrocytes include transport of nutrients and hormones from the circulation to the brain, storage of glycogen, participation in glucose sensing, synaptic plasticity, uptake and metabolism of neurotransmitters, release of substances to modify neurotransmission, and cytokine production, amongst others. In the hypothalamus, these physiological glial functions impact on neuronal circuits that control systemic metabolism to modify their outputs. The initial response of astrocytes to poor dietary habits and obesity involves activation of neuroprotective mechanisms but, with chronic exposure to these situations, hypothalamic astrocytes participate in the development of some of the damaging secondary effects. The present review discusses not only some of the physiological functions of hypothalamic astrocytes in metabolism, but also their role in the secondary complications of obesity, such as insulin resistance and cardiovascular affectations.
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Affiliation(s)
- Julie A Chowen
- Department of Endocrinology, Hospital Infantil Universitario Niño Jesús, Instituto de Investigación la Princesa, Madrid, Spain
- CIBEROBN (Centro de Investigación Biomédica en Red sobre Fisiopatología de la Obesidad y Nutrición), Instituto de Salud Carlos III, Madrid, Spain
- IMDEA Food Institute, CEI UAM + CSIC, Madrid, Spain
| | - Laura M Frago
- Department of Endocrinology, Hospital Infantil Universitario Niño Jesús, Instituto de Investigación la Princesa, Madrid, Spain
- CIBEROBN (Centro de Investigación Biomédica en Red sobre Fisiopatología de la Obesidad y Nutrición), Instituto de Salud Carlos III, Madrid, Spain
- Department of Pediatrics, Universidad Autónoma de Madrid, Madrid, Spain
| | - María Soledad Fernández-Alfonso
- Instituto Pluridisciplinar UCM y Departamento de Farmacología, Farmacognosia y Botánica, Facultad de Farmacia, Universidad Complutense, Madrid, Spain
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MacDonald AJ, Robb JL, Morrissey NA, Beall C, Ellacott KLJ. Astrocytes in neuroendocrine systems: An overview. J Neuroendocrinol 2019; 31:e12726. [PMID: 31050045 DOI: 10.1111/jne.12726] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/04/2019] [Revised: 04/26/2019] [Accepted: 04/28/2019] [Indexed: 12/11/2022]
Abstract
A class of glial cell, astrocytes, is highly abundant in the central nervous system (CNS). In addition to maintaining tissue homeostasis, astrocytes regulate neuronal communication and synaptic plasticity. There is an ever-increasing appreciation that astrocytes are involved in the regulation of physiology and behaviour in normal and pathological states, including within neuroendocrine systems. Indeed, astrocytes are direct targets of hormone action in the CNS, via receptors expressed on their surface, and are also a source of regulatory neuropeptides, neurotransmitters and gliotransmitters. Furthermore, as part of the neurovascular unit, astrocytes can regulate hormone entry into the CNS. This review is intended to provide an overview of how astrocytes are impacted by and contribute to the regulation of a diverse range of neuroendocrine systems: energy homeostasis and metabolism, reproduction, fluid homeostasis, the stress response and circadian rhythms.
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Affiliation(s)
- Alastair J MacDonald
- Neuroendocrine Research Group, Institute of Biomedical & Clinical Sciences, University of Exeter Medical School, Exeter, UK
| | - Josephine L Robb
- Neuroendocrine Research Group, Institute of Biomedical & Clinical Sciences, University of Exeter Medical School, Exeter, UK
| | - Nicole A Morrissey
- Neuroendocrine Research Group, Institute of Biomedical & Clinical Sciences, University of Exeter Medical School, Exeter, UK
| | - Craig Beall
- Neuroendocrine Research Group, Institute of Biomedical & Clinical Sciences, University of Exeter Medical School, Exeter, UK
| | - Kate L J Ellacott
- Neuroendocrine Research Group, Institute of Biomedical & Clinical Sciences, University of Exeter Medical School, Exeter, UK
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50
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Mowry FE, Biancardi VC. Neuroinflammation in hypertension: the renin-angiotensin system versus pro-resolution pathways. Pharmacol Res 2019; 144:279-291. [PMID: 31039397 DOI: 10.1016/j.phrs.2019.04.029] [Citation(s) in RCA: 30] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/01/2019] [Revised: 04/22/2019] [Accepted: 04/23/2019] [Indexed: 12/31/2022]
Abstract
Overstimulation of the pro-inflammatory pathways within brain areas responsible for sympathetic outflow is well evidenced as a primary contributing factor to the establishment and maintenance of neurogenic hypertension. However, the precise mechanisms and stimuli responsible for promoting a pro-inflammatory state are not fully elucidated. Recent work has unveiled novel compounds derived from omega-3 polyunsaturated fatty acids (ω-3 PUFAs), termed specialized pro-resolving mediators (SPMs), which actively regulate the resolution of inflammation. Failure or dysregulation of the resolution process has been linked to a variety of chronic inflammatory and neurodegenerative diseases. Given the pathologic role of neuroinflammation in the hypertensive state, SPMs and their associated pathways may provide a link between hypertension and the long-standing association of dietary ω-3 PUFAs with cardioprotection. Herein, we review recent progress in understanding the RAS-driven pathophysiology of neurogenic hypertension, particularly in regards to the chronic low-grade neuroinflammatory response. In addition, we examine the potential for an impaired resolution of inflammation process in the context of hypertension.
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Affiliation(s)
- Francesca Elisabeth Mowry
- Department of Anatomy, Physiology, and Pharmacology, College of Veterinary Medicine, Auburn University, Alabama, USA
| | - Vinicia Campana Biancardi
- Department of Anatomy, Physiology, and Pharmacology, College of Veterinary Medicine, Auburn University, Alabama, USA; Center for Neurosciences Research Initiative, Auburn University, Alabama, USA.
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