1
|
Hao WY, Wang JX, Xu XY, Chen JL, Chen Q, Li YH, Zhu GQ, Chen AD. Chemerin in caudal division of nucleus tractus solitarius increases sympathetic activity and blood pressure. Eur J Neurosci 2024; 60:4830-4842. [PMID: 39044301 DOI: 10.1111/ejn.16475] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2023] [Revised: 06/28/2024] [Accepted: 07/08/2024] [Indexed: 07/25/2024]
Abstract
Chemerin is an adipokine that contributes to metabolism regulation. Nucleus tractus solitarius (NTS) is the first relay station in the brain for accepting various visceral afferent activities for regulating cardiovascular activity. However, the roles of chemerin in the NTS in regulating sympathetic activity and blood pressure are almost unknown. This study aimed to determine the role and potential mechanism of chemerin in the NTS in modulating sympathetic outflow and blood pressure. Bilateral NTS microinjections were performed in anaesthetized adult male Sprague-Dawley rats. Renal sympathetic nerve activity (RSNA), mean arterial pressure (MAP) and heart rate (HR) were continuously recorded. Chemerin and its receptor chemokine-like receptor 1 (CMKLR1) were highly expressed in caudal NTS (cNTS). Microinjection of chemerin-9 to the cNTS increased RSNA, MAP and HR, which were prevented by CMKLR1 antagonist α-NETA, superoxide scavenger tempol or N-acetyl cysteine, nicotinamide adenine dinucleotide phosphate (NADPH) oxidase inhibitors diphenyleneiodonium or apocynin. Chemerin-9 increased superoxide production and NADPH oxidase activity in the cNTS. The increased superoxide production induced by chemerin-9 was inhibited by α-NETA. The effects of cNTS microinjection of chemerin-9 on the RSNA, MAP and HR were attenuated by the pretreatment with paraventricular nucleus (PVN) microinjection of NMDA receptor antagonist MK-801 rather than AMPA/kainate receptor antagonist CNQX. These results indicate that chemerin-9 in the NTS increases sympathetic outflow, blood pressure and HR via CMKLR1-mediated NADPH oxidase activation and subsequent superoxide production in anaesthetized normotensive rats. Glutamatergic inputs in the PVN are needed for the chemerin-9-induced responses.
Collapse
Affiliation(s)
- Wen-Yuan Hao
- Key Laboratory of Targeted Intervention of Cardiovascular Disease, Collaborative Innovation Center for Cardiovascular Disease Translational Medicine, and Department of Physiology, Nanjing Medical University, Nanjing, Jiangsu, China
| | - Jing-Xiao Wang
- Key Laboratory of Targeted Intervention of Cardiovascular Disease, Collaborative Innovation Center for Cardiovascular Disease Translational Medicine, and Department of Physiology, Nanjing Medical University, Nanjing, Jiangsu, China
| | - Xiao-Yu Xu
- Key Laboratory of Targeted Intervention of Cardiovascular Disease, Collaborative Innovation Center for Cardiovascular Disease Translational Medicine, and Department of Physiology, Nanjing Medical University, Nanjing, Jiangsu, China
| | - Jun-Liu Chen
- Key Laboratory of Targeted Intervention of Cardiovascular Disease, Collaborative Innovation Center for Cardiovascular Disease Translational Medicine, and Department of Physiology, Nanjing Medical University, Nanjing, Jiangsu, China
| | - Qi Chen
- Department of Pathophysiology, Nanjing Medical University, Nanjing, Jiangsu, China
| | - Yue-Hua Li
- Department of Pathophysiology, Nanjing Medical University, Nanjing, Jiangsu, China
| | - Guo-Qing Zhu
- Key Laboratory of Targeted Intervention of Cardiovascular Disease, Collaborative Innovation Center for Cardiovascular Disease Translational Medicine, and Department of Physiology, Nanjing Medical University, Nanjing, Jiangsu, China
| | - Ai-Dong Chen
- Key Laboratory of Targeted Intervention of Cardiovascular Disease, Collaborative Innovation Center for Cardiovascular Disease Translational Medicine, and Department of Physiology, Nanjing Medical University, Nanjing, Jiangsu, China
| |
Collapse
|
2
|
van Weperen VYH, Ripplinger CM, Vaseghi M. Autonomic control of ventricular function in health and disease: current state of the art. Clin Auton Res 2023; 33:491-517. [PMID: 37166736 PMCID: PMC10173946 DOI: 10.1007/s10286-023-00948-8] [Citation(s) in RCA: 10] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2023] [Accepted: 04/20/2023] [Indexed: 05/12/2023]
Abstract
PURPOSE Cardiac autonomic dysfunction is one of the main pillars of cardiovascular pathophysiology. The purpose of this review is to provide an overview of the current state of the art on the pathological remodeling that occurs within the autonomic nervous system with cardiac injury and available neuromodulatory therapies for autonomic dysfunction in heart failure. METHODS Data from peer-reviewed publications on autonomic function in health and after cardiac injury are reviewed. The role of and evidence behind various neuromodulatory therapies both in preclinical investigation and in-use in clinical practice are summarized. RESULTS A harmonic interplay between the heart and the autonomic nervous system exists at multiple levels of the neuraxis. This interplay becomes disrupted in the setting of cardiovascular disease, resulting in pathological changes at multiple levels, from subcellular cardiac signaling of neurotransmitters to extra-cardiac, extra-thoracic remodeling. The subsequent detrimental cycle of sympathovagal imbalance, characterized by sympathoexcitation and parasympathetic withdrawal, predisposes to ventricular arrhythmias, progression of heart failure, and cardiac mortality. Knowledge on the etiology and pathophysiology of this condition has increased exponentially over the past few decades, resulting in a number of different neuromodulatory approaches. However, significant knowledge gaps in both sympathetic and parasympathetic interactions and causal factors that mediate progressive sympathoexcitation and parasympathetic dysfunction remain. CONCLUSIONS Although our understanding of autonomic imbalance in cardiovascular diseases has significantly increased, specific, pivotal mediators of this imbalance and the recognition and implementation of available autonomic parameters and neuromodulatory therapies are still lagging.
Collapse
Affiliation(s)
- Valerie Y H van Weperen
- Division of Cardiology, Department of Medicine, UCLA Cardiac Arrythmia Center, University of California, 100 Medical Plaza, Suite 660, Los Angeles, CA, 90095, USA
| | | | - Marmar Vaseghi
- Division of Cardiology, Department of Medicine, UCLA Cardiac Arrythmia Center, University of California, 100 Medical Plaza, Suite 660, Los Angeles, CA, 90095, USA.
| |
Collapse
|
3
|
Hermes TDA, Mizobuti DS, da Rocha GL, da Silva HNM, Covatti C, Pereira ECL, Ferretti R, Minatel E. Tempol improves redox status in mdx dystrophic diaphragm muscle. Int J Exp Pathol 2020; 101:289-297. [PMID: 33098599 DOI: 10.1111/iep.12376] [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: 02/13/2020] [Revised: 08/10/2020] [Accepted: 08/23/2020] [Indexed: 12/15/2022] Open
Abstract
Oxidative stress is a critical element in relationship to the pathophysiology of Duchenne muscular dystrophy (DMD). In the mice the diaphragm (DIA) is most resembles the dystrophic human pathology. In this study we have evaluated the consequences of a synthetic antioxidant (tempol) on oxidative stress parameters in the DIA muscle of mdx mice. The mdx mice were separated into two groups: mdx, the control group receiving intraperitoneal (i.p.) injections of saline solution (100 µL), and mdxT, the treated group receiving i.p. injections of tempol (100 mg/kg). The tempol-treated group showed reduced oxidative stress markers, decreasing the dihydroethidium reaction (DHE) area; autofluorescent lipofuscin granules; and 4-hydroxynonenal (4-HNE)-protein adduct levels. DIA muscle of mdx mice. At the same time, the manganese-superoxide dismutase 2 (SOD2) levels were increased in the tempol-treated group. In addition, the tempol-treated group showed reduced levels of glutathione-disulphide reductase (GSR), glutathione peroxidase 1 (GPx1) and catalase (CAT) in immunoblots. The tempol-treated group has also shown lower relative gene expression of SOD1, CAT and GPx than the non-treated group. Our data demonstrated that tempol treatment reduced oxidant parameters and increased anti-oxidant SOD2 levels in the DIA muscle of mdx mice, which may contribute to the normalization of the redox homeostasis of dystrophic muscles.
Collapse
Affiliation(s)
- Túlio de Almeida Hermes
- Department of Structural and Functional Biology, Institute of Biology, State University of Campinas (UNICAMP), Campinas, Brazil
| | - Daniela Sayuri Mizobuti
- Department of Structural and Functional Biology, Institute of Biology, State University of Campinas (UNICAMP), Campinas, Brazil
| | - Guilherme Luiz da Rocha
- Department of Structural and Functional Biology, Institute of Biology, State University of Campinas (UNICAMP), Campinas, Brazil
| | | | - Caroline Covatti
- Department of Structural and Functional Biology, Institute of Biology, State University of Campinas (UNICAMP), Campinas, Brazil
| | - Elaine Cristina Leite Pereira
- Department of Structural and Functional Biology, Institute of Biology, State University of Campinas (UNICAMP), Campinas, Brazil.,Faculty of Ceilandia, University of Brasilia (UnB), Brasília, Brazil
| | - Renato Ferretti
- Department of Anatomy, Institute of Bioscience of Botucatu, São Paulo State University (UNESP), Botucatu, Brazil
| | - Elaine Minatel
- Department of Structural and Functional Biology, Institute of Biology, State University of Campinas (UNICAMP), Campinas, Brazil
| |
Collapse
|
4
|
Wang Q, Deng F, Zhu D. Superoxide anions modulate the effects of alarin in the paraventricular nucleus on sympathetic activity and blood pressure in spontaneously hypertensive rats. Neuropeptides 2020; 80:102021. [PMID: 32033788 DOI: 10.1016/j.npep.2020.102021] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/10/2019] [Revised: 01/19/2020] [Accepted: 01/19/2020] [Indexed: 12/19/2022]
Abstract
Neuropeptides are involved in the regulation of the sympathetic activity and blood pressure in the paraventricular nucleus of the hypothalamus (PVN). The present study was designed to determine how alarin modulates the renal sympathetic nerve activity (RSNA), arterial blood pressure and mean arterial pressure (MAP) in the PVN, and whether superoxide anions regulate the effects of alarin in the PVN of spontaneously hypertensive rats (SHRs). Acute experiment was carried out with male Wistar-Kyoto rats (WKY) and SHRs under anesthesia. RSNA, systolic blood pressure (SBP), diastolic blood pressure (DBP), and MAP were measured. Alarin microinjection into the PVN increased RSNA (7.8 ± 1.8 vs. 14.8 ± 2.3%), SBP (5.9 ± 1.4 vs. 12.1 ± 1.6 mmHg), DBP (5.1 ± 0.8 vs. 10.0 ± 1.1 mmHg), and MAP (5.4 ± 1.2 vs. 10.7 ± 1.3 mmHg) in WKY rats and SHRs,. Alarin antagonist ala6-25 Cys decreased RSNA, SBP, DBP, and MAP in SHRs, and inhibited the effects of alarin. The alarin level was increased in the PVN of SHR compared to WKY rats. (29.7 ± 4.9 vs. 14.6 ± 2.4 pg/mg protein). PVN microinjection of superoxide anion scavengers tempol and tiron, or NAD(P)H oxidase inhibitor apocynin, decreased RSNA, SBP, DBP, and MAP in SHRs, and inhibited the effects of alarin, but the superoxide dismutase inhibitor diethyldithiocarbamic acid potentiated the effects of alarin. Superoxide anions and NAD(P)H oxidase activity levels in the PVN were increased by alarin, but decreased by alarin antagonist ala6-25 Cys. The alarin-induced increases in superoxide anions and NAD(P)H oxidase activity levels were abolished by pre-treatment with ala6-25 Cys. The results suggest that alarin in the PVN increases sympathetic outflow and blood pressure. The enhanced activity of endogenous alarin in the PVN contributes to sympathetic activation in hypertension, and the superoxide anion is involved in these alarin-mediated processes in the PVN.
Collapse
Affiliation(s)
- Qian Wang
- Pediatric Department, Shanghai General Hospital, Shanghai, China
| | - Fanxin Deng
- Department of Cardiothoracic Surgery, Sir Run Run Hospital, Nanjing Medical University, Nanjing, China
| | - Dawei Zhu
- Department of Cardiothoracic Surgery, Sir Run Run Hospital, Nanjing Medical University, Nanjing, China.
| |
Collapse
|
5
|
Zhao Y, Li Y, Li Z, Xu B, Chen P, Yang X. Superoxide anions modulate the performance of apelin in the paraventricular nucleus on sympathetic activity and blood pressure in spontaneously hypertensive rats. Peptides 2019; 121:170051. [PMID: 30582943 DOI: 10.1016/j.peptides.2018.12.005] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/25/2018] [Revised: 12/17/2018] [Accepted: 12/18/2018] [Indexed: 01/24/2023]
Abstract
The present study was designed to determine how apelin in paraventricular nucleus (PVN) modulates the renal sympathetic nerve activity (RSNA), arterial blood pressure (ABP), mean arterial pressure (MAP), and heart rate (HR), and whether superoxide anions regulate the performance of PVN apelin in spontaneously hypertensive rats (SHRs). Acute experiment was carried out with 13-week-old male Wistar-Kyoto rats (WKY) and SHRs under anaesthesia. RSNA, ABP, MAP and HR after PVN microinjection were measured. Apelin microinjection into PVN increased RSNA, ABP, MAP and HR in WKY rats and SHRs, more obviously in SHRs. APJ antagonist F13A decreased the RSNA, ABP, MAP and HR in SHRs, and inhibited the effects of apelin. Apelin and APJ mRNA levels were higher in the PVN in SHRs. PVN microinjection of superoxide anion scavengers tempol and tiron, or NAD(P)H oxidase inhibitor apocynin, decreased the RSNA, ABP, MAP and HR in SHRs, and inhibited the effects of apelin, but the superoxide dismutase (SOD) inhibitor diethyldithiocarbamic acid (DETC) potentiated the effects of apelin. NAD(P)H oxidase activity and superoxide anion levels in PVN were increased by apelin, but decreased by APJ antagonist F13A. The apelin-induced increases in NAD(P)H oxidase activity and superoxide anion level were abolished by pre-treatment with F13A. These results indicate that apelin in PVN increases the sympathetic outflow and blood pressure via activating APJ receptor. The enhanced activity of endogenous apelin and APJ receptor in PVN contributes to sympathetic activation in hypertension, and the superoxide anion is involved in these apelin-mediated processes in PVN.
Collapse
Affiliation(s)
- Yuewu Zhao
- Department of Cardiology, The First Affiliated Hospital of Soochow University, Suzhou, China; Department of Cardiology, Xuzhou No. 1 People's Hospital, Xuzhou, China
| | - Yong Li
- Department of Cardiology, The First Affiliated Hospital of Nanjing Medical University, Nanjing, China
| | - Zhengzhang Li
- Department of Cardiology, The First Affiliated Hospital of Soochow University, Suzhou, China
| | - Bing Xu
- Department of Cardiology, The First Affiliated Hospital of Soochow University, Suzhou, China
| | - Peng Chen
- Department of Cardiology, The First Affiliated Hospital of Soochow University, Suzhou, China
| | - Xiangjun Yang
- Department of Cardiology, The First Affiliated Hospital of Soochow University, Suzhou, China.
| |
Collapse
|
6
|
Kulthinee S, Rakmanee S, Michael Wyss J, Roysommuti S. Taurine Supplementation Ameliorates the Adverse Effects of Perinatal Taurine Depletion and High Sugar Intake on Cardiac Ischemia/Reperfusion Injury of Adult Female Rats. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2018; 975 Pt 2:741-755. [PMID: 28849496 DOI: 10.1007/978-94-024-1079-2_58] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 03/18/2023]
Abstract
Perinatal taurine depletion followed by high sugar intake after weaning adversely affects myocardial and arterial pressure function following a myocardial ischemia and reperfusion (IR) insult in adult female rats. This study tests the hypothesis that taurine supplementation ameliorates this adverse effect. Female Sprague-Dawley rats were fed normal rat chow and drank water containing β-alanine from conception until weaning (taurine depletion, TD). After weaning, female offspring were fed normal rat chow and drank either water containing 5% glucose (TDG) or water alone (TDW). At 6-7 weeks of age, half the rats in each group were supplemented with taurine and 1 week later subjected to cardiac IR. Body weight, heart weight, plasma electrolytes, plasma creatinine, blood urea nitrogen, and hematocrit were not significantly different among the four groups. The mean arterial pressures significantly increased in all groups after IR, but values were not significantly different among the four groups. Heart rates were significantly increased after IR only in TDW group. Compared to TDW, TDG displayed increased plasma cardiac injury markers (creatinine kinase-MB, troponin T, and N-terminal prohormone brain natriuretic peptide), increased sympathetic activity, decreased parasympathetic activity, and decreased baroreflex sensitivity after IR. Taurine supplementation completely restored the baroreflex and autonomic dysfunction of TDG to TDW levels and partially decreased myocardial injury after cardiac IR. The present study indicates that in adult female rats, perinatal taurine depletion followed by high sugar intake after weaning exacerbates cardiac IR injury and arterial pressure dysregulation and these adverse effects can be partially prevented by taurine supplementation.
Collapse
Affiliation(s)
- Supaporn Kulthinee
- Department of Physiology, Faculty of Medicine, Khon Kaen University, Khon Kaen, 40002, Thailand
| | - Sasipa Rakmanee
- Department of Physiology, Faculty of Medicine, Khon Kaen University, Khon Kaen, 40002, Thailand
| | - J Michael Wyss
- Department of Cell, Developmental and Integrative Biology, School of Medicine, University of Alabama at Birmingham, Birmingham, AL, 35294, USA
| | - Sanya Roysommuti
- Department of Physiology, Faculty of Medicine, Khon Kaen University, Khon Kaen, 40002, Thailand.
| |
Collapse
|
7
|
Lu P, Jiang SJ, Pan H, Xu AL, Wang GH, Ma CL, Shi Z. Short hairpin RNA interference targeting interleukin 1 receptor type I in the paraventricular nucleus attenuates hypertension in rats. Pflugers Arch 2017; 470:439-448. [PMID: 29143938 DOI: 10.1007/s00424-017-2081-0] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2017] [Revised: 10/11/2017] [Accepted: 10/16/2017] [Indexed: 01/08/2023]
Abstract
Blood pressure is controlled by tonic sympathetic activities, excessive activation of which contributes to the pathogenesis and progression of hypertension. Interleukin (IL)-1β in the paraventricular nucleus (PVN) is involved in sympathetic overdrive and hypertension. Here, we investigated the therapeutic effects of IL-1 receptor type I (IL-1R1) gene silencing in the PVN on hypertension. Recombinant lentivirus vectors expressing a short hairpin RNA (shRNA) targeting IL-1R1 (Lv-shR-IL-1R1) or a control shRNA were microinjected into PVN of spontaneously hypertensive rats (SHRs) and normotensive WKY rats. The fluorescence of green fluorescent protein-labelled vectors appeared at 2 weeks after injection and persisted for at least 8 weeks. IL-1R1 protein expression in the PVN was reduced 4 weeks after Lv-shR-IL-1R1 injection in SHRs. IL-1R1 interference also reduced basal sympathetic activity, cardiac sympathetic afferent reflex in SHRs. Depressor effects were observed from week 2 to 10 after Lv-shR-IL-1R1 treatment in SHRs, with the most prominent effects seen at the end of week 4. Furthermore, Lv-shR-IL-1R1 treatment decreased the ratio of left ventricular weight to body weight and cross-sectional areas of myocardial cells in SHRs. Additionally, Lv-shR-IL-1R1 treatment prevented an increase in superoxide anion and pro-inflammatory cytokines (PICs, TNF-α and IL-1β) in the PVN of SHR, and upregulated anti-inflammatory cytokine (AIC, IL-10) expression. These results indicate that shRNA interference targeting IL-1R1 in the PVN decreases arterial blood pressure, attenuates excessive sympathetic activity and cardiac sympathetic afferent reflex, and improves myocardial remodelling in SHRs by restoring the balance between PICs and AICs to attenuate oxidative stress.
Collapse
Affiliation(s)
- Peng Lu
- Department of Education, Yantai Affiliated Hospital of Binzhou Medical University, Yantai, 264003, China.,Shandong Province Key Laboratory of Stroke, Yantai, 264003, China
| | - Shu-Jun Jiang
- Department of Physiology, Binzhou Medical University, 346 Guanhai Rd, Laishan District, Yantai, Shandong Province, 264003, China
| | - Hong Pan
- Department of Physiology, Binzhou Medical University, 346 Guanhai Rd, Laishan District, Yantai, Shandong Province, 264003, China
| | - Ai-Li Xu
- Department of Physiology, Binzhou Medical University, 346 Guanhai Rd, Laishan District, Yantai, Shandong Province, 264003, China
| | - Gui-Hua Wang
- Experimental Teaching Management Center, Binzhou Medical University, Yantai, 264003, China
| | - Chun-Lei Ma
- Department of Physiology, Binzhou Medical University, 346 Guanhai Rd, Laishan District, Yantai, Shandong Province, 264003, China.,Shandong Province Key Laboratory of Stroke, Yantai, 264003, China
| | - Zhen Shi
- Department of Physiology, Binzhou Medical University, 346 Guanhai Rd, Laishan District, Yantai, Shandong Province, 264003, China.
| |
Collapse
|
8
|
Ren X, Zhang F, Zhao M, Zhao Z, Sun S, Fraidenburg DR, Tang H, Han Y. Angiotensin-(1-7) in Paraventricular Nucleus Contributes to the Enhanced Cardiac Sympathetic Afferent Reflex and Sympathetic Activity in Chronic Heart Failure Rats. Cell Physiol Biochem 2017; 42:2523-2539. [PMID: 28848201 PMCID: PMC6022399 DOI: 10.1159/000480214] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2017] [Accepted: 06/15/2017] [Indexed: 01/08/2023] Open
Abstract
Background/Aims Cardiac sympathetic afferent reflex (CSAR) enhancement contributes to exaggerated sympathetic activation in chronic heart failure (CHF). The current study aimed to investigate the roles of angiotensin (Ang)-(1-7) in CSAR modulation and sympathetic activation and Ang-(1-7) signaling pathway in paraventricular nucleus of CHF rats. Methods CHF was induced by coronary artery ligation. Responses of renal sympathetic nerve activity (RSNA) and mean arterial pressure (MAP) to epicardial application of capsaicin were used to evaluate CSAR in rats with anesthesia. Results Ang-(1-7) increased RSNA, MAP, CSAR activity, cAMP level, NAD(P)H oxidase activity and superoxide anion level more significantly in CHF than in sham-operated rats, while Mas receptor antagonist A-779 had the opposite effects. Moreover, Ang-(1-7) augmented effects of Ang II in CHF rats. The effects of Ang-(1-7) were blocked by A-779, adenylyl cyclase inhibitor SQ22536, protein kinase A inhibitor Rp-cAMP, superoxide anion scavenger tempol and NAD(P)H oxidase inhibitor apocynin. Mas and AT1 receptor protein expressions, Ang-(1-7) and Ang II levels in CHF increased. Conclusions These results indicate that Ang-(1-7) in paraventricular nucleus enhances CSAR and sympathetic output not only by exerting its own effects but also by augmenting the effects of Ang II through Mas receptor in CHF. Endogenous Ang-(1-7)/Mas receptor activity contributes to CSAR enhancement and sympathetic activation in CHF, and NAD(P)H oxidase-derived superoxide anions and the cAMP-PKA signaling pathway are involved in mediating the effects of Ang-(1-7) in CHF.
Collapse
Affiliation(s)
- Xingsheng Ren
- Key Laboratory of Cardiovascular Disease and Molecular Intervention, Department of Physiology, Nanjing Medical University, Nanjing, China
| | - Feng Zhang
- Key Laboratory of Cardiovascular Disease and Molecular Intervention, Department of Physiology, Nanjing Medical University, Nanjing, China
| | - Mingxia Zhao
- Key Laboratory of Cardiovascular Disease and Molecular Intervention, Department of Physiology, Nanjing Medical University, Nanjing, China
| | - Zhenzhen Zhao
- Key Laboratory of Cardiovascular Disease and Molecular Intervention, Department of Physiology, Nanjing Medical University, Nanjing, China.,The first clinical medical college, Nanjing Medical University, Nanjing, China
| | - Shuo Sun
- Key Laboratory of Cardiovascular Disease and Molecular Intervention, Department of Physiology, Nanjing Medical University, Nanjing, China
| | - Dustin R Fraidenburg
- Division of Translational and Regenerative Medicine, Department of Medicine, University of Arizona, Tucson, Arizona, USA.,Department of Medicine, University of Illinois at Chicago, Chicago, Illinois, USA
| | - Haiyang Tang
- Division of Translational and Regenerative Medicine, Department of Medicine, University of Arizona, Tucson, Arizona, USA
| | - Ying Han
- Key Laboratory of Cardiovascular Disease and Molecular Intervention, Department of Physiology, Nanjing Medical University, Nanjing, China
| |
Collapse
|
9
|
Ma L, Zhu J, Gao Q, Rebecchi MJ, Wang Q, Liu L. Restoring Pharmacologic Preconditioning in the Aging Heart: Role of Mitophagy/Autophagy. J Gerontol A Biol Sci Med Sci 2017; 72:489-498. [PMID: 27565512 DOI: 10.1093/gerona/glw168] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2016] [Accepted: 07/27/2016] [Indexed: 12/16/2022] Open
Abstract
We previously reported that pretreatment with the potent antioxidant TEMPOL improves mitochondrial function and restores preconditioning in the aging heart. Because mitophagy is implicated in cardiac preconditioning and declines with age, this study was designed to investigate how age influences mitophagy in response to preconditioning and whether TEMPOL pretreatment improves it. Old (22-24 months) rats were pretreated with or without 4-week TEMPOL and compared with young (4-6 months) untreated rats. Cardioprotection induced by isoflurane (ISO) in vivo and in isolated cardiomyocytes in vitro was assessed following ischemia/reperfusion and simulated hypoxia/reoxygenation, respectively. Mitophagy was determined by comparing the levels/subcellular locations of key mitophagic markers using Western blotting and immunofluorescence techniques. ISO preconditioned the young but not old heart in vivo and in vitro. Aging impaired ISO-induced mitochondrial accumulation of PINK1 and Parkin, as well as mitochondrial ubiquitination, and baseline and ISO-induced autophagic flux assessed by LC3 puncta, membrane associated LC3-II and p62. Pretreatment with TEMPOL improved these processes and restored ISO preconditioning. Inhibition of autophagy abolished ISO-induced protection in cardiomyocytes from young and TEMPOL pretreated old rats. Thus, antioxidant pretreatment significantly improves mitophagic response to ISO in old myocardium, which may contribute to restoration of cardioprotection in senescent animals.
Collapse
Affiliation(s)
- Li Ma
- Department of Anesthesiology, School of Medicine, Stony Brook University, New York
| | - Jiang Zhu
- Department of Anesthesiology, The Second Affiliated Hospital of Soochow University, Suzhou, Jiangsu, People's Republic of China
| | - Qun Gao
- Department of Anesthesiology, School of Medicine, Stony Brook University, New York
| | - Mario J Rebecchi
- Department of Anesthesiology, School of Medicine, Stony Brook University, New York
| | - Qiang Wang
- Department of Anesthesiology, The First Affiliated Hospital of Xi'an Jiaotong University, Xi'an, Shaanxi, People's Republic of China
| | - Lixin Liu
- Department of Anesthesiology, School of Medicine, Stony Brook University, New York
| |
Collapse
|
10
|
Kaur J, Young BE, Fadel PJ. Sympathetic Overactivity in Chronic Kidney Disease: Consequences and Mechanisms. Int J Mol Sci 2017; 18:ijms18081682. [PMID: 28767097 PMCID: PMC5578072 DOI: 10.3390/ijms18081682] [Citation(s) in RCA: 79] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2017] [Revised: 07/20/2017] [Accepted: 07/28/2017] [Indexed: 12/19/2022] Open
Abstract
The incidence of chronic kidney disease (CKD) is increasing worldwide, with more than 26 million people suffering from CKD in the United States alone. More patients with CKD die of cardiovascular complications than progress to dialysis. Over 80% of CKD patients have hypertension, which is associated with increased risk of cardiovascular morbidity and mortality. Another common, perhaps underappreciated, feature of CKD is an overactive sympathetic nervous system. This elevation in sympathetic nerve activity (SNA) not only contributes to hypertension but also plays a detrimental role in the progression of CKD independent of any increase in blood pressure. Indeed, high SNA is associated with poor prognosis and increased cardiovascular morbidity and mortality independent of its effect on blood pressure. This brief review will discuss some of the consequences of sympathetic overactivity and highlight some of the potential pathways contributing to chronically elevated SNA in CKD. Mechanisms leading to chronic sympathoexcitation in CKD are complex, multifactorial and to date, not completely understood. Identification of the mechanisms and/or signals leading to sympathetic overactivity in CKD are crucial for development of effective therapeutic targets to reduce the increased cardiovascular risk in this patient group.
Collapse
Affiliation(s)
- Jasdeep Kaur
- Department of Kinesiology, University of Texas at Arlington, Arlington, TX 76019, USA.
| | - Benjamin E Young
- Department of Kinesiology, University of Texas at Arlington, Arlington, TX 76019, USA.
| | - Paul J Fadel
- Department of Kinesiology, University of Texas at Arlington, Arlington, TX 76019, USA.
| |
Collapse
|
11
|
Shimokawa T, Tsutsui H, Miura T, Nishinaka T, Terada T, Takama M, Yoshida S, Tanba T, Tojo A, Yamagata M, Yukimura T. Renoprotective effect of yohimbine on ischaemia/reperfusion-induced acute kidney injury through α2C-adrenoceptors in rats. Eur J Pharmacol 2016; 781:36-44. [DOI: 10.1016/j.ejphar.2016.03.059] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2015] [Revised: 03/25/2016] [Accepted: 03/30/2016] [Indexed: 11/29/2022]
|
12
|
Angiotensin-(1–7) enhances the effects of angiotensin II on the cardiac sympathetic afferent reflex and sympathetic activity in rostral ventrolateral medulla in renovascular hypertensive rats. ACTA ACUST UNITED AC 2015; 9:865-77. [DOI: 10.1016/j.jash.2015.08.005] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2015] [Revised: 04/11/2015] [Accepted: 08/06/2015] [Indexed: 11/21/2022]
|
13
|
Zhou Q, Zhou X, TuEr-Hong ZL, Wang H, Yin T, Li Y, Zhang L, Lu Y, Xing Q, Zhang J, Yang Y, Tang B. Renal sympathetic denervation suppresses atrial fibrillation induced by acute atrial ischemia/infarction through inhibition of cardiac sympathetic activity. Int J Cardiol 2015; 203:187-95. [PMID: 26512836 DOI: 10.1016/j.ijcard.2015.10.120] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/20/2015] [Revised: 10/13/2015] [Accepted: 10/16/2015] [Indexed: 12/14/2022]
Abstract
OBJECTIVE This study aims to explore the effects of renal sympathetic denervation (RSD) on atrial fibrillation (AF) inducibility and sympathetic activity induced by acute atrial ischemia/infarction. METHODS Acute ischemia/infarction was induced in 12 beagle dogs by ligating coronary arteries that supply the atria. Six dogs in the sham-RSD group did not undergo RSD, and six dogs without coronary artery ligation served as controls. AF induction rate, sympathetic discharge, catecholamine concentration and densities of tyrosine hydroxylase-positive nerves were measured. RESULTS Acute atrial ischemia/infarction resulted in a significant increase of AF induction rate, which was decreased by RSD compared to controls (P<0.05). The root-mean-square peak value, peak area and number of sympathetic discharges were significantly augmented by atrial ischemia relative to the baseline and control (P<0.05). The number of sympathetic discharges was significantly reduced in the RSD group, compared to the control and sham-RSD groups (P<0.05). Norepinephrine and epinephrine concentrations in the atria, ventricle and kidney were elevated by atrial ischemia/infarction, but were reduced by RSD (P<0.05). CONCLUSIONS Sympathetic hyperactivity was associated with pacing-induced AF after acute atrial ischemia/infarction. RSD has the potential to reduce the incidence of new-onset AF after acute atrial ischemia/infarction. The inhibition of cardiac sympathetic activity by RSD may be one of the major underlying mechanisms for the marked reduction of AF inducibility.
Collapse
Affiliation(s)
- Qina Zhou
- Clinical Medicine, Postdoctoral Scientific Research Station, Xinjiang Medical University, Urumqi, China
| | - Xianhui Zhou
- Heart Center, Cardiac Pacing and Electrophysiology Department, The First Affiliated Hospital of Xinjiang Medical University, Urumqi, China
| | - ZuKe-la TuEr-Hong
- Heart Center, Cardiac Pacing and Electrophysiology Department, The First Affiliated Hospital of Xinjiang Medical University, Urumqi, China
| | - Hongli Wang
- Clinical Medical Research Institute, The First Affiliated Hospital of Xinjiang Medical University, Urumqi, China
| | - Tingting Yin
- Heart Center, Cardiac Pacing and Electrophysiology Department, The First Affiliated Hospital of Xinjiang Medical University, Urumqi, China
| | - Yaodong Li
- Heart Center, Cardiac Pacing and Electrophysiology Department, The First Affiliated Hospital of Xinjiang Medical University, Urumqi, China
| | - Ling Zhang
- Heart Center, Cardiac Pacing and Electrophysiology Department, The First Affiliated Hospital of Xinjiang Medical University, Urumqi, China
| | - Yanmei Lu
- Heart Center, Cardiac Pacing and Electrophysiology Department, The First Affiliated Hospital of Xinjiang Medical University, Urumqi, China
| | - Qiang Xing
- Heart Center, Cardiac Pacing and Electrophysiology Department, The First Affiliated Hospital of Xinjiang Medical University, Urumqi, China
| | - Jianghua Zhang
- Heart Center, Cardiac Pacing and Electrophysiology Department, The First Affiliated Hospital of Xinjiang Medical University, Urumqi, China
| | - Yining Yang
- Clinical Medical Research Institute, The First Affiliated Hospital of Xinjiang Medical University, Urumqi, China.
| | - Baopeng Tang
- Heart Center, Cardiac Pacing and Electrophysiology Department, The First Affiliated Hospital of Xinjiang Medical University, Urumqi, China.
| |
Collapse
|
14
|
Sang HQ, Jiang ZM, Zhao QP, Xin F. MicroRNA-133a improves the cardiac function and fibrosis through inhibiting Akt in heart failure rats. Biomed Pharmacother 2015; 71:185-9. [DOI: 10.1016/j.biopha.2015.02.030] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2015] [Accepted: 02/21/2015] [Indexed: 11/16/2022] Open
|
15
|
Chen WW, Xiong XQ, Chen Q, Li YH, Kang YM, Zhu GQ. Cardiac sympathetic afferent reflex and its implications for sympathetic activation in chronic heart failure and hypertension. Acta Physiol (Oxf) 2015; 213:778-94. [PMID: 25598170 DOI: 10.1111/apha.12447] [Citation(s) in RCA: 63] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2014] [Revised: 10/22/2014] [Accepted: 12/23/2014] [Indexed: 12/21/2022]
Abstract
Persistent excessive sympathetic activation greatly contributes to the pathogenesis of chronic heart failure (CHF) and hypertension. Cardiac sympathetic afferent reflex (CSAR) is a sympathoexcitatory reflex with positive feedback characteristics. Humoral factors such as bradykinin, adenosine and reactive oxygen species produced in myocardium due to myocardial ischaemia stimulate cardiac sympathetic afferents and thereby reflexly increase sympathetic activity and blood pressure. The CSAR is enhanced in myocardial ischaemia, CHF and hypertension. The enhanced CSAR at least partially contributes to the sympathetic activation and pathogenesis of these diseases. Nucleus of the solitary tract (NTS), hypothalamic paraventricular nucleus (PVN) and rostral ventrolateral medulla are the most important central sites involved in the modulation and integration of the CSAR. Angiotensin II, AT1 receptors and NAD(P)H oxidase-derived superoxide anions pathway in the PVN are mainly responsible for the enhanced CSAR in CHF and hypertension. Central angiotensin-(1-7), nitric oxide, endothelin, intermedin, hydrogen peroxide and several other signal molecules are involved in regulating CSAR. Blockade of the CSAR shows beneficial effects in CHF and hypertension. This review focuses on the anatomical and physiological basis of the CSAR, the interaction of CSAR with baroreflex and chemoreflex, and the role of enhanced CSAR in the pathogenesis of CHF and hypertension.
Collapse
Affiliation(s)
- W.-W. Chen
- Department of Physiology; Key Laboratory of Cardiovascular Disease and Molecular Intervention; Nanjing Medical University; Nanjing Jiangsu China
| | - X.-Q. Xiong
- Department of Physiology; Key Laboratory of Cardiovascular Disease and Molecular Intervention; Nanjing Medical University; Nanjing Jiangsu China
| | - Q. Chen
- Department of Pathophysiology; Nanjing Medical University; Nanjing Jiangsu China
| | - Y.-H. Li
- Department of Pathophysiology; Nanjing Medical University; Nanjing Jiangsu China
| | - Y.-M. Kang
- Department of Physiology and Pathophysiology; Cardiovascular Research Center; Xi'an Jiaotong University School of Medicine; Xi'an China
| | - G.-Q. Zhu
- Department of Physiology; Key Laboratory of Cardiovascular Disease and Molecular Intervention; Nanjing Medical University; Nanjing Jiangsu China
| |
Collapse
|
16
|
Sun HJ, Zhou H, Feng XM, Gao Q, Ding L, Tang CS, Zhu GQ, Zhou YB. Superoxide anions in the paraventricular nucleus mediate cardiac sympathetic afferent reflex in insulin resistance rats. Acta Physiol (Oxf) 2014; 212:267-82. [PMID: 25307720 DOI: 10.1111/apha.12405] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2014] [Revised: 05/26/2014] [Accepted: 10/06/2014] [Indexed: 12/14/2022]
Abstract
AIM Cardiac sympathetic afferent reflex (CSAR) participates in sympathetic over-excitation. Superoxide anions and angiotensin II (Ang II) mechanisms are associated with sympathetic outflow and CSAR in the paraventricular nucleus (PVN). This study was designed to investigate whether PVN superoxide anions mediate CSAR and Ang II-induced CSAR enhancement response in fructose-induced insulin resistance (IR) rats. METHODS CSAR was evaluated with the changes of renal sympathetic nerve activity (RSNA) and mean arterial pressure (MAP) responses to the epicardial application of capsaicin (CAP) in anaesthetized rats. RESULTS Compared with Control rats, IR rats showed that CSAR, PVN NAD(P)H oxidase activity, superoxide anions, malondialdehyde (MDA), Ang II and AT1 receptor levels were significantly increased, whereas PVN superoxide dismutase (SOD) and catalase (CAT) activities were decreased. In Control and IR rats, PVN microinjection of superoxide anions scavengers tempol, tiron and PEG-SOD (an analogue of endogenous superoxide dismutase) or inhibition of PVN NAD(P)H oxidase with apocynin caused significant reduction of CSAR, respectively, but DETC (a superoxide dismutase inhibitor) strengthened the CSAR. PVN pre-treatment with tempol abolished, whereas DETC potentiated, Ang II-induced CSAR enhancement response. Moreover, PVN pre-treatment with tempol or losartan prevented superoxide anions increase caused by Ang II in IR rats. CONCLUSION PVN superoxide anions mediate CSAR and Ang II-induced CSAR response in IR rats. In IR state, increased NAD(P)H oxidase activity and decreased SOD and CAT activities in the PVN promote superoxide anions increase to involve in CSAR enhancement. Ang II may increase NAD(P)H oxidase activity via AT1 receptor to induce superoxide anion production.
Collapse
Affiliation(s)
- H.-J. Sun
- Key Laboratory of Cardiovascular Disease and Molecular Intervention; Department of Physiology; Nanjing Medical University; Nanjing China
| | - H. Zhou
- Laboratory Center for Basic Medical Sciences; Nanjing Medical University; Nanjing China
| | - X.-M. Feng
- Clinical Laboratory of Luyi Xian People's Hospital; Zhoukou China
| | - Q. Gao
- Laboratory Center for Basic Medical Sciences; Nanjing Medical University; Nanjing China
| | - L. Ding
- Key Laboratory of Cardiovascular Disease and Molecular Intervention; Department of Physiology; Nanjing Medical University; Nanjing China
| | - C.-S. Tang
- Key Laboratory of Molecular Cardiovascular Science; Ministry of Education; Beijing China
| | - G.-Q. Zhu
- Key Laboratory of Cardiovascular Disease and Molecular Intervention; Department of Physiology; Nanjing Medical University; Nanjing China
| | - Y.-B. Zhou
- Key Laboratory of Cardiovascular Disease and Molecular Intervention; Department of Physiology; Nanjing Medical University; Nanjing China
| |
Collapse
|
17
|
Ziolo MT, Houser SR. Abnormal Ca(2+) cycling in failing ventricular myocytes: role of NOS1-mediated nitroso-redox balance. Antioxid Redox Signal 2014; 21:2044-59. [PMID: 24801117 PMCID: PMC4208612 DOI: 10.1089/ars.2014.5873] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
SIGNIFICANCE Heart failure (HF) results from poor heart function and is the leading cause of death in Western society. Abnormalities of Ca(2+) handling at the level of the ventricular myocyte are largely responsible for much of the poor heart function. RECENT ADVANCES Although studies have unraveled numerous mechanisms for the abnormal Ca(2+) handling, investigations over the past decade have indicated that much of the contractile dysfunction and adverse remodeling that occurs in HF involves oxidative stress. CRITICAL ISSUES Regrettably, antioxidant therapy has been an immense disappointment in clinical trials. Thus, redox signaling is being reassessed to elucidate why antioxidants failed to treat HF. FUTURE DIRECTIONS A recently identified aspect of redox signaling (specifically the superoxide anion radical) is its interaction with nitric oxide, known as the nitroso-redox balance. There is a large nitroso-redox imbalance with HF, and we suggest that correcting this imbalance may be able to restore myocyte contraction and improve heart function.
Collapse
Affiliation(s)
- Mark T Ziolo
- 1 Department of Physiology and Cell Biology, Davis Heart and Lung Research Institute, The Ohio State University , Columbus, Ohio
| | | |
Collapse
|
18
|
Gao L, Zhu T, Xie G, Lou X, Li S, Zhou Y, Deng Z, Chu D, Lou J, Du D. GABA(A) receptor overexpression in the lateral hypothalamic area attenuates gastric ischemia‑reperfusion injury in rats. Mol Med Rep 2014; 11:1057-62. [PMID: 25354809 DOI: 10.3892/mmr.2014.2816] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2014] [Accepted: 08/22/2014] [Indexed: 11/05/2022] Open
Abstract
Excessive activation of the greater splanchnic nerve (GSN) has previously been determined to contribute to the progression of gastric ischemia‑reperfusion (GI‑R) injury. The present study was designed to estimate the protective effects of GABAA receptor (GABA(A)R) overexpression in the lateral hypothalamic area (LHA) against GI‑R injury. The GI‑R injury model was induced in rats by clamping the celiac artery for 30 min and then reperfusing for 1 h. Microinjection of recombinant adenoviral vectors overexpressing GABA(A)R (Ad‑GABA(A)R) or control adenoviral vectors (Ad‑Con) into the LHA was conducted in GI‑R and normal control rats. Significant protective effects were observed on day 2 after Ad‑GABA(A)R treatment in the GI‑R injury rats. Ad‑GABA(A)R treatment reduced plasma norepinephrine levels, plasma angiotensin II levels and peripheral GSN activity, but increased the gastric mucosal blood flow, as compared with Ad‑Con treatment. These results indicate that adenoviral vector‑induced GABA(A)R overexpression in the LHA blunts GSN activity and subsequently alleviates the effects of gastric injury in GI‑R rats.
Collapse
Affiliation(s)
- Lin Gao
- Department of Neurology, The Affiliated Second Hospital of Zhengzhou University, Zhengzhou, Henan 450014, P.R. China
| | - Tao Zhu
- Laboratory of Neuropharmacology and Neurotoxicology, Shanghai University, Shanghai 200444, P.R. China
| | - Guilin Xie
- Life Science College of Northeast Agricultural University, Harbin, Heilongjiang 150030, P.R. China
| | - Xiangxin Lou
- Department of Bioengineering, College of Chemistry, Chemical Engineering and Biotechnology, Donghua University, Shanghai 201620, P.R. China
| | - Shibao Li
- Department of Laboratory Medicine, Lianyungang Hospital Affiliated Bengbu Medical College, Lianyungang, Jiangsu 222006, P.R. China
| | - Yan Zhou
- Department of Laboratory Medicine, Lianyungang Hospital Affiliated Bengbu Medical College, Lianyungang, Jiangsu 222006, P.R. China
| | - Zhenxu Deng
- Department of Life Science, Heze University, Heze, Shandong 274500, P.R. China
| | - Dechang Chu
- Department of Life Science, Heze University, Heze, Shandong 274500, P.R. China
| | - Jiyu Lou
- Department of Neurology, The Affiliated Second Hospital of Zhengzhou University, Zhengzhou, Henan 450014, P.R. China
| | - Dongshu Du
- Laboratory of Neuropharmacology and Neurotoxicology, Shanghai University, Shanghai 200444, P.R. China
| |
Collapse
|
19
|
Salusin-β in rostral ventrolateral medulla increases sympathetic outflow and blood pressure via superoxide anions in hypertensive rats. J Hypertens 2014; 32:1059-67; discussion 1067. [DOI: 10.1097/hjh.0000000000000143] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
|
20
|
Sun HJ, Zhang LL, Fan ZD, Chen D, Zhang L, Gao XY, Kang YM, Zhu GQ. Superoxide anions involved in sympathoexcitation and pressor effects of salusin-β in paraventricular nucleus in hypertensive rats. Acta Physiol (Oxf) 2014; 210:534-45. [PMID: 24304512 DOI: 10.1111/apha.12188] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2013] [Revised: 07/18/2013] [Accepted: 10/23/2013] [Indexed: 12/20/2022]
Abstract
AIMS Salusin-β in paraventricular nucleus (PVN) increases renal sympathetic nerve activity (RSNA), mean arterial pressure (MAP), heart rate (HR) and arginine vasopressin (AVP) release in hypertensive rats but not in normal rats. The present study was designed to investigate the downstream molecular mechanism of salusin-β in the PVN in hypertension. METHOD Renovascular hypertension was induced by two-kidney, one-clip (2K1C) in male SD rats. Acute experiments were carried out 4 weeks after 2K1C or sham operation under anaesthesia. RESULTS MrgA1 mRNA expression and salusin-β level in the PVN as well as plasma salusin-β level were increased in 2K1C rats. Bilateral PVN microinjection of salusin-β increased the RSNA, MAP and HR in 2K1C rats, which were abolished by the pre-treatment with polyethylene glycol-superoxide dismutase (PEG-SOD), the superoxide anion scavenger tempol, the NAD(P)H oxidase inhibitor apocynin or the protein kinase C (PKC) inhibitor chelerythrine chloride (CLC), but not affected by the AT1 receptor antagonist losartan, the Mas receptor antagonist A-779, the NOS inhibitor L-NAME or the GABAA and GABAB receptor antagonists gabazine+CGP-35348. Salusin-β-induced increases in superoxide anion level and NAD(P)H oxidase activity in the PVN were abolished by the PVN pre-treatment with CLC. Salusin-β increased AVP levels in rostral ventrolateral medulla and plasma, which were prevented by the pre-treatment with PEG-SOD, apocynin or CLC in 2K1C rats. Salusin-β augmented the enhanced activity of PKC in the PVN in 2K1C rats. CONCLUSION Protein kinase C-NAD(P)H oxidase-superoxide anions pathway in the PVN is involved in salusin-β-induced sympathetic activation, pressor response and AVP release in renovascular hypertension.
Collapse
Affiliation(s)
- H.-J. Sun
- Key Laboratory of Cardiovascular Disease and Molecular Intervention; Department of Physiology; Nanjing Medical University; Nanjing China
| | - L.-L. Zhang
- Key Laboratory of Cardiovascular Disease and Molecular Intervention; Department of Physiology; Nanjing Medical University; Nanjing China
| | - Z.-D. Fan
- Department of Rheumatology and Immunology; Nanjing Children's Hospital Affiliated to Nanjing Medical University; Nanjing China
| | - D. Chen
- Key Laboratory of Cardiovascular Disease and Molecular Intervention; Department of Physiology; Nanjing Medical University; Nanjing China
| | - L. Zhang
- Key Laboratory of Cardiovascular Disease and Molecular Intervention; Department of Physiology; Nanjing Medical University; Nanjing China
| | - X.-Y. Gao
- Key Laboratory of Cardiovascular Disease and Molecular Intervention; Department of Physiology; Nanjing Medical University; Nanjing China
| | - Y.-M. Kang
- Department of Physiology and Pathophysiology; Cardiovascular Research Center; Xi'an Jiaotong University School of Medicine; Xi'an China
| | - G.-Q. Zhu
- Key Laboratory of Cardiovascular Disease and Molecular Intervention; Department of Physiology; Nanjing Medical University; Nanjing China
| |
Collapse
|
21
|
Ding L, Zhang LL, Gao R, Chen D, Wang JJ, Gao XY, Kang YM, Zhu GQ. Superoxide anions in paraventricular nucleus modulate adipose afferent reflex and sympathetic activity in rats. PLoS One 2013; 8:e83771. [PMID: 24376743 PMCID: PMC3871588 DOI: 10.1371/journal.pone.0083771] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2013] [Accepted: 11/08/2013] [Indexed: 01/04/2023] Open
Abstract
Background Adipose afferent reflex (AAR) is a sympatho-excitatory reflex induced by chemical stimulation of white adipose tissue (WAT). Ionotropic glutamate receptors including NMDA receptors (NMDAR) and non-NMDA receptors (non-NMDAR) in paraventricular nucleus (PVN) mediate the AAR. Enhanced AAR contributes to sympathetic activation and hypertension in obesity rats. This study was designed to investigate the role and mechanism of superoxide anions in PVN in modulating the AAR. Methodology/Principal Findings Renal sympathetic nerve activity (RSNA) and mean arterial pressure (MAP) were recorded in anesthetized rats. AAR was evaluated by the RSNA and MAP responses to injections of capsaicin into four sites of right inguinal WAT (8.0 nmol in 8.0 µl for each site). Microinjection of polyethylene glycol-superoxide dismutase (PEG-SOD), the superoxide anion scavenger tempol or the NAD(P)H oxidase inhibitor apocynin into the PVN decreased the baseline RSNA and MAP, and attenuated the AAR. Unilateral WAT injection of capsaicin increased superoxide anions in bilateral PVN, which was prevented by the WAT denervation. WAT injection of capsaicin increased superoxide anion level and NAD(P)H oxidase activity in the PVN, which was abolished by the PVN pretreatment with the combined NMDAR antagonist AP5 and non-NMDAR antagonist CNQX. Microinjection of the NMDAR agonist NMDA or the non-NMDAR agonist AMPA increased superoxide anion level and NAD(P)H oxidase activity in the PVN. Conclusions NAD(P)H oxidase-derived superoxide anions in the PVN contributes to the tonic modulation of AAR. Activation of ionotropic glutamate receptors in the PVN is involved in the AAR-induced production of superoxide anions in the PVN.
Collapse
Affiliation(s)
- Lei Ding
- Key Laboratory of Cardiovascular Disease and Molecular Intervention, Department of Physiology, Nanjing Medical University, Nanjing, Jiangsu, China
| | - Ling-Li Zhang
- Key Laboratory of Cardiovascular Disease and Molecular Intervention, Department of Physiology, Nanjing Medical University, Nanjing, Jiangsu, China
| | - Run Gao
- Key Laboratory of Cardiovascular Disease and Molecular Intervention, Department of Physiology, Nanjing Medical University, Nanjing, Jiangsu, China
| | - Dan Chen
- Key Laboratory of Cardiovascular Disease and Molecular Intervention, Department of Physiology, Nanjing Medical University, Nanjing, Jiangsu, China
| | - Jue-Jin Wang
- Key Laboratory of Cardiovascular Disease and Molecular Intervention, Department of Physiology, Nanjing Medical University, Nanjing, Jiangsu, China
| | - Xing-Ya Gao
- Key Laboratory of Cardiovascular Disease and Molecular Intervention, Department of Physiology, Nanjing Medical University, Nanjing, Jiangsu, China
| | - Yu-Ming Kang
- Department of Physiology and Pathophysiology, Cardiovascular Research Center, Xi'an Jiaotong University School of Medicine, Xi'an, Shanxi, China
| | - Guo-Qing Zhu
- Key Laboratory of Cardiovascular Disease and Molecular Intervention, Department of Physiology, Nanjing Medical University, Nanjing, Jiangsu, China
- * E-mail:
| |
Collapse
|
22
|
Hou Y, Hu J, Po SS, Wang H, Zhang L, Zhang F, Wang K, Zhou Q. Catheter-based renal sympathetic denervation significantly inhibits atrial fibrillation induced by electrical stimulation of the left stellate ganglion and rapid atrial pacing. PLoS One 2013; 8:e78218. [PMID: 24223140 PMCID: PMC3819364 DOI: 10.1371/journal.pone.0078218] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2013] [Accepted: 09/10/2013] [Indexed: 12/22/2022] Open
Abstract
Background Sympathetic activity involves the pathogenesis of atrial fibrillation (AF). Renal sympathetic denervation (RSD) decreases sympathetic renal afferent nerve activity, leading to decreased central sympathetic drive. The aim of this study was to identify the effects of RSD on AF inducibility induced by hyper-sympathetic activity in a canine model. Methods To establish a hyper-sympathetic tone canine model of AF, sixteen dogs were subjected to stimulation of left stellate ganglion (LSG) and rapid atrial pacing (RAP) for 3 hours. Then animals in the RSD group (n = 8) underwent radiofrequency ablation of the renal sympathetic nerve. The control group (n = 8) underwent the same procedure except for ablation. AF inducibility, effective refractory period (ERP), ERP dispersion, heart rate variability and plasma norepinephrine levels were measured at baseline, after stimulation and after ablation. Results LSG stimulation combined RAP significantly induced higher AF induction rate, shorter ERP, larger ERP dispersion at all sites examined and higher plasma norepinephrine levels (P<0.05 in all values), compared to baseline. The increased AF induction rate, shortened ERP, increased ERP dispersion and elevated plasma norepinephrine levels can be almost reversed by RSD, compared to the control group (P<0.05). LSG stimulation combined RAP markedly shortened RR-interval and standard deviation of all RR-intervals (SDNN), Low-frequency (LF), high-frequency (HF) and LF/HF ratio (P<0.05). These changes can be reversed by RSD, compared to the control group (P<0.05). Conclusions RSD significantly reduced AF inducibility and reversed the atrial electrophysiological changes induced by hyper-sympathetic activity.
Collapse
Affiliation(s)
- Yuemei Hou
- Department of Cardiovascular Diseases, The 6th People’s Hospital affiliated to Shanghai Jiaotong University, Shanghai, China
| | - Jialu Hu
- Department of Cardiovascular Diseases, Zhongshan Hospital Fudan University, Shanghai, China
| | - Sunny S. Po
- Heart Rhythm Institute and Department of Medicine, University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma, United States of America
| | - Huan Wang
- Arrhythmia Research Lab, First Affiliated Hospital of Xinjiang Medical University, Urumqi, China
| | - Ling Zhang
- Arrhythmia Research Lab, First Affiliated Hospital of Xinjiang Medical University, Urumqi, China
| | - Feng Zhang
- Arrhythmia Research Lab, First Affiliated Hospital of Xinjiang Medical University, Urumqi, China
| | - Kun Wang
- Arrhythmia Research Lab, First Affiliated Hospital of Xinjiang Medical University, Urumqi, China
| | - Qina Zhou
- Arrhythmia Research Lab, First Affiliated Hospital of Xinjiang Medical University, Urumqi, China
- * E-mail:
| |
Collapse
|
23
|
Chan SHH, Chan JYH. Angiotensin-generated reactive oxygen species in brain and pathogenesis of cardiovascular diseases. Antioxid Redox Signal 2013; 19:1074-84. [PMID: 22429119 DOI: 10.1089/ars.2012.4585] [Citation(s) in RCA: 47] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
SIGNIFICANCE Overproduction of angiotensin II (Ang II) in brain contributes to the pathogenesis of cardiovascular diseases. One of the most promising theses that emerged during the last decade is that production of reactive oxygen species (ROS) and activation of redox-dependent signaling cascades underlie those Ang II actions. This review summarizes our status of understanding on the roles of ROS and redox-sensitive signaling in brain Ang II-dependent cardiovascular diseases, using hypertension and heart failure as illustrative examples. RECENT ADVANCES ROS generated by NADPH oxidase, mitochondrial electron transport chain, and proinflammatory cytokines activates mitogen-activated protein kinases and transcription factors, which in turn modulate ion channel functions and ultimately increase neuronal activity and sympathetic outflow in brain Ang II-dependent cardiovascular diseases. Antioxidants targeting ROS have been demonstrated to be beneficial to Ang II-induced hypertension and heart failure via protection from oxidative stress in brain regions that subserve cardiovascular regulation. CRITICAL ISSUES Intra-neuronal signaling and the downstream redox-sensitive proteins involved in controlling the neuronal discharge rate, the sympathetic outflow, and the pathogenesis of cardiovascular diseases need to be identified. The cross talk between Ang II-induced oxidative stress and neuroinflammation in neural mechanisms of cardiovascular diseases also warrants further elucidation. FUTURE DIRECTIONS Future studies are needed to identify new redox-based therapeutics that work not only in animal models, but also in patients suffering from the prevalent diseases. Upregulation of endogenous antioxidants in the regulation of ROS homeostasis is a potential therapeutic target, as are small molecule- or nanoformulated conjugate-based antioxidant therapy.
Collapse
Affiliation(s)
- Samuel H H Chan
- Center for Translational Research in Biomedical Sciences, Kaohsiung Chang Gung Memorial Hospital , Kaohsiung, Taiwan, Republic of China
| | | |
Collapse
|
24
|
Rosenbaugh EG, Savalia KK, Manickam DS, Zimmerman MC. Antioxidant-based therapies for angiotensin II-associated cardiovascular diseases. Am J Physiol Regul Integr Comp Physiol 2013; 304:R917-28. [PMID: 23552499 DOI: 10.1152/ajpregu.00395.2012] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Cardiovascular diseases, including hypertension and heart failure, are associated with activation of the renin-angiotensin system (RAS) and increased circulating and tissue levels of ANG II, a primary effector peptide of the RAS. Through its actions on various cell types and organ systems, ANG II contributes to the pathogenesis of cardiovascular diseases by inducing cardiac and vascular hypertrophy, vasoconstriction, sodium and water reabsorption in kidneys, sympathoexcitation, and activation of the immune system. Cardiovascular research over the past 15-20 years has clearly implicated an important role for elevated levels of reactive oxygen species (ROS) in mediating these pathophysiological actions of ANG II. As such, the use of antioxidants, to reduce the elevated levels of ROS, as potential therapies for various ANG II-associated cardiovascular diseases has been intensely investigated. Although some antioxidant-based therapies have shown therapeutic impact in animal models of cardiovascular disease and in human patients, others have failed. In this review, we discuss the benefits and limitations of recent strategies, including gene therapy, dietary sources, low-molecular-weight free radical scavengers, polyethylene glycol conjugation, and nanomedicine-based technologies, which are designed to deliver antioxidants for the improved treatment of cardiovascular diseases. Although much work has been completed, additional research focusing on developing specific antioxidant molecules or proteins and identifying the ideal in vivo delivery system for such antioxidants is necessary before the use of antioxidant-based therapies for cardiovascular diseases become a clinical reality.
Collapse
Affiliation(s)
- Erin G Rosenbaugh
- Department of Cellular and Integrative Physiology, Nebraska Center for Nanomedicine, University of Nebraska Medical Center, Omaha, NE 68198, USA
| | | | | | | |
Collapse
|
25
|
Malondialdehyde and 4-hydroxynonenal adducts are not formed on cardiac ryanodine receptor (RyR2) and sarco(endo)plasmic reticulum Ca2+-ATPase (SERCA2) in diabetes. Mol Cell Biochem 2013; 376:121-35. [PMID: 23354458 DOI: 10.1007/s11010-013-1558-1] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2012] [Accepted: 01/09/2013] [Indexed: 12/31/2022]
Abstract
Recently, we reported an elevated level of glucose-generated carbonyl adducts on cardiac ryanodine receptor (RyR2) and sarco(endo)plasmic reticulum Ca(2+)-ATPase (SERCA2) in hearts of streptozotocin(STZ)-induced diabetic rats. We also showed these adduct impaired RyR2 and SERCA2 activities, and altered evoked Ca(2+) transients. What is less clear is if lipid-derived malondialdehyde (MDA) and 4-hydroxy-2-nonenal (4-HNE) also chemically react with and impair RyR2 and SERCA2 activities in diabetes? This study used western blot assays with adduct-specific antibodies and confocal microscopy to assess levels of MDA, 4-HNE, N (ε)-carboxy(methyl)lysine (CML), pentosidine, and pyrraline adducts on RyR2 and SERCA2 and evoked intracellular transient Ca(2+) kinetics in myocytes from control, diabetic, and treated-diabetic rats. MDA and 4-HNE adducts were not detected on RyR2 and SERCA2 from either control or 8 weeks diabetic rats with altered evoked Ca(2+) transients. However, CML, pentosidine, and pyrraline adducts were elevated three- to five-fold (p < 0.05). Treating diabetic rats with pyridoxamine (a scavenger of reactive carbonyl species, RCS) or aminoguanidine (a mixed reactive oxygen species-RCS scavenger) reduced CML, pentosidine, and pyrraline adducts on RyR2 and SERCA2 and blunted SR Ca(2+) cycling changes. Treating diabetic rats with the superoxide dismutase mimetic tempol had no impact on MDA and 4-HNE adducts on RyR2 and SERCA2, and on SR Ca(2+) cycling. From these data we conclude that lipid-derived MDA and 4-HNE adducts are not formed on RyR2 and SERCA2 in this model of diabetes, and are therefore unlikely to be directly contributing to the SR Ca(2+) dysregulation.
Collapse
|
26
|
Sun HJ, Li P, Chen WW, Xiong XQ, Han Y. Angiotensin II and angiotensin-(1-7) in paraventricular nucleus modulate cardiac sympathetic afferent reflex in renovascular hypertensive rats. PLoS One 2012; 7:e52557. [PMID: 23285085 PMCID: PMC3527547 DOI: 10.1371/journal.pone.0052557] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2012] [Accepted: 11/15/2012] [Indexed: 11/18/2022] Open
Abstract
BACKGROUND The enhanced cardiac sympathetic afferent reflex (CSAR) is involved in the sympathetic activation that contributes to the pathogenesis and progression of hypertension. Activation of AT(1) receptors by angiotension (Ang) II in the paraventricular nucleus (PVN) augments the enhanced CSAR and sympathetic outflow in hypertension. The present study is designed to determine whether Ang-(1-7) in PVN plays the similar roles as Ang II and the interaction between Ang-(1-7) and Ang II on CSAR in renovascular hypertension. METHODOLOGY/PRINCIPAL FINDINGS The two-kidney, one-clip (2K1C) method was used to induce renovascular hypertension. The CSAR was evaluated by the renal sympathetic nerve activity (RSNA) and mean arterial pressure (MAP) responses to epicardial application of capsaicin in sinoaortic-denervated and cervical-vagotomized rats with urethane and α-chloralose anesthesia. Either Ang II or Ang-(1-7) in PVN caused greater increases in RSNA and MAP, and enhancement in CSAR in 2K1C rats than in sham-operated (Sham) rats. Mas receptor antagonist A-779 and AT(1) receptor antagonist losartan induced opposite effects to Ang-(1-7) or Ang II respectively in 2K1C rats, but losartan had no effects in Sham rats. Losartan but not the A-779 abolished the effects of Ang II, while A-779 but not the losartan blocked the effects of Ang-(1-7). PVN pretreatment with Ang-(1-7) dose-dependently augmented the RSNA, MAP, and CSAR responses to the Ang II in 2K1C rats. Ang II level, AT(1) receptor and Mas receptor protein expression in PVN increased in 2K1C rats compared with Sham rats but Ang-(1-7) level did not. CONCLUSIONS Ang-(1-7) in PVN is as effective as Ang II in enhancing the CSAR and increasing sympathetic outflow and both endogenous Ang-(1-7) and Ang II in PVN contribute to the enhanced CSAR and sympathetic outflow in renovascular hypertension. Ang-(1-7) in PVN potentiates the effects of Ang II in renovascular hypertension.
Collapse
Affiliation(s)
- Hai-Jian Sun
- Department of Physiology, Nanjing Medical University, Nanjing, Jiangsu, China
| | - Peng Li
- Department of Physiology, Nanjing Medical University, Nanjing, Jiangsu, China
| | - Wei-Wei Chen
- Department of Physiology, Nanjing Medical University, Nanjing, Jiangsu, China
| | - Xiao-Qing Xiong
- Department of Physiology, Nanjing Medical University, Nanjing, Jiangsu, China
| | - Ying Han
- Department of Physiology, Nanjing Medical University, Nanjing, Jiangsu, China
| |
Collapse
|
27
|
Wang Y, Seto SW, Golledge J. Angiotensin II, sympathetic nerve activity and chronic heart failure. Heart Fail Rev 2012; 19:187-98. [DOI: 10.1007/s10741-012-9368-1] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
|
28
|
Hydrogen sulfide in paraventricular nucleus enhances sympathetic activity and cardiac sympathetic afferent reflex in chronic heart failure rats. PLoS One 2012; 7:e50102. [PMID: 23166827 PMCID: PMC3499499 DOI: 10.1371/journal.pone.0050102] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2012] [Accepted: 10/19/2012] [Indexed: 11/19/2022] Open
Abstract
BACKGROUND Intracerebroventricular infusion of NaHS, a hydrogen sulfide (H(2)S) donor, increased mean arterial pressure (MAP). This study was designed to determine the roles of H(2)S in the paraventricular nucleus (PVN) in modulating sympathetic activity and cardiac sympathetic afferent reflex (CSAR) in chronic heart failure (CHF). METHODOLOGY/PRINCIPAL FINDINGS CHF was induced by left descending coronary artery ligation in rats. Renal sympathetic nerve activity (RSNA) and MAP were recorded under anesthesia. CSAR was evaluated by the RSNA and MAP responses to epicardial application of capsaicin. PVN microinjection of low doses of a H(2)S donor, GYY4137 (0.01 and 0.1 nmol), had no significant effects on RSNA, MAP and CSAR. High doses of GYY4137 (1, 2 and 4 nmol) increased baseline RSNA, MAP and heart rate (HR), and enhanced CSAR. The effects were greater in CHF rats than sham-operated rats. A cystathionine-β-synthase (CBS) inhibitor, hydroxylamine (HA) in PVN had no significant effect on the RSNA, MAP and CSAR. CBS activity and H(2)S level in the PVN were decreased in CHF rats. No significant difference in CBS level in PVN was found between sham-operated rats and CHF rats. Stimulation of cardiac sympathetic afferents with capsaicin decreased CBS activity and H(2)S level in the PVN in both sham-operated rats and CHF rats. CONCLUSIONS Exogenous H(2)S in PVN increases RSNA, MAP and HR, and enhances CSAR. The effects are greater in CHF rats than those in sham-operated rats. Endogenous H(2)S in PVN is not responsible for the sympathetic activation and enhanced CSAR in CHF rats.
Collapse
|
29
|
SOD1 gene transfer into paraventricular nucleus attenuates hypertension and sympathetic activity in spontaneously hypertensive rats. Pflugers Arch 2012; 465:261-70. [PMID: 23114721 DOI: 10.1007/s00424-012-1173-0] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2012] [Revised: 10/15/2012] [Accepted: 10/22/2012] [Indexed: 10/27/2022]
Abstract
Excessive sympathetic activity contributes to the initiation and progression of hypertension. Reactive oxygen species in the paraventricular nucleus (PVN) is involved in sympathetic overdrive and hypertension. The present study was designed to investigate whether superoxide dismutase 1 (SOD1) overexpression in the PVN attenuated sympathetic activation and hypertension. Adenoviral vectors containing human SOD1 or null adenoviral vectors were microinjected into the PVN of Wistar rats and spontaneously hypertensive rats (SHR). Significant depressor effects were observed from weeks 1 to 4 after SOD1 gene transfer in SHR. Acute experiments were carried out at the end of the 3rd week. In the PVN, superoxide anion and angiotensin II levels were increased while SOD1 activity and protein expression were decreased in SHR, which were attenuated by SOD1 overexpression in the PVN. However, SOD1 overexpression had no significant effect on the SOD2 activity in the PVN. The blood pressure response to ganglionic blockade, cardiac sympathetic nerve activity, and cardiac sympathetic afferent reflex (CSAR) were enhanced, and the plasma norepinephrine level was increased in SHR, which were prevented by SOD1 gene transfer in the PVN. Furthermore, SOD1 overexpression decreased the ratio of left ventricular weight to body weight, cross-sectional areas of myocardial cells, media thickness, and the media/lumen ratio of small arteries in the heart in SHR. These results indicate that SOD1 overexpression in the PVN reduces arterial blood pressure, attenuates excessive sympathetic activity and CSAR, and improves myocardial and vascular remodeling in SHR.
Collapse
|
30
|
Li P, Zhang F, Zhou YB, Cui BP, Han Y. Superoxide anions modulate the effects of angiotensin-(1–7) in the rostral ventrolateral medulla on cardiac sympathetic afferent reflex and sympathetic activity in rats. Neuroscience 2012; 223:388-98. [DOI: 10.1016/j.neuroscience.2012.07.048] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2012] [Revised: 06/28/2012] [Accepted: 07/19/2012] [Indexed: 11/15/2022]
|
31
|
Chen AD, Xiong XQ, Gan XB, Zhang F, Zhou YB, Gao XY, Han Y. Endothelin-1 in paraventricular nucleus modulates cardiac sympathetic afferent reflex and sympathetic activity in rats. PLoS One 2012; 7:e40748. [PMID: 22815806 PMCID: PMC3398005 DOI: 10.1371/journal.pone.0040748] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2012] [Accepted: 06/12/2012] [Indexed: 02/01/2023] Open
Abstract
Background Cardiac sympathetic afferent reflex (CSAR) is a positive-feedback, sympathoexcitatory reflex. Paraventricular nucleus (PVN) is an important component of the central neurocircuitry of the CSAR. The present study is designed to determine whether endothelin-1 (ET-1) in the PVN modulates the CSAR and sympathetic activity, and whether superoxide anions are involved in modulating the effects of ET-1 in the PVN in rats. Methodology/Principal Findings In anaesthetized Sprague–Dawley rats with cervical vagotomy and sinoaortic denervation, renal sympathetic nerve activity (RSNA) and mean arterial pressure (MAP) were recorded. The CSAR was evaluated by the responses of the RSNA and MAP to epicardial application of capsaicin. Microinjection of ET-1 into the bilateral PVN dose-dependently enhanced the CSAR, increased the baseline RSNA and MAP. The effects of ET-1 were blocked by PVN pretreatment with the ETA receptor antagonist BQ-123. However, BQ-123 alone had no significant effects on the CSAR, the baseline RSNA and MAP. Bilateral PVN pretreatment with either superoxide anion scavenger tempol or polyethylene glycol-superoxide dismutase (PEG-SOD) inhibited the effects of ET-1 on the CSAR, RSNA and MAP. Microinjection of ET-1 into the PVN increased the superoxide anion level in the PVN, which was abolished by PVN pretreatment with BQ-123. Epicardial application of capsaicin increased superoxide anion level in PVN which was further enhanced by PVN pretreatment with ET-1. Conclusions Exogenous activation of ETA receptors with ET-1 in the PVN enhances the CSAR, increases RSNA and MAP. Superoxide anions in PVN are involved in the effects of ET-1 in the PVN.
Collapse
Affiliation(s)
- Ai-Dong Chen
- Department of Physiology, Nanjing Medical University, Nanjing, China
- Department of Clinical Pharmacy, Yijishan Hospital of Wannan Medical College, Wuhu, China
| | - Xiao-Qing Xiong
- Department of Physiology, Nanjing Medical University, Nanjing, China
| | - Xian-Bing Gan
- Department of Physiology, Nanjing Medical University, Nanjing, China
| | - Feng Zhang
- Department of Physiology, Nanjing Medical University, Nanjing, China
| | - Ye-Bo Zhou
- Department of Physiology, Nanjing Medical University, Nanjing, China
| | - Xing-Ya Gao
- Department of Physiology, Nanjing Medical University, Nanjing, China
| | - Ying Han
- Department of Physiology, Nanjing Medical University, Nanjing, China
- * E-mail:
| |
Collapse
|
32
|
Zhang L, Xiong XQ, Fan ZD, Gan XB, Gao XY, Zhu GQ. Involvement of enhanced cardiac sympathetic afferent reflex in sympathetic activation in early stage of diabetes. J Appl Physiol (1985) 2012; 113:47-55. [DOI: 10.1152/japplphysiol.01228.2011] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Cardiac sympathetic afferent reflex (CSAR) is involved in sympathetic activation. The present study was designed to investigate the contribution of enhanced CSAR to sympathetic activation in the early stage of diabetes and the involvement of AT1 receptors in the paraventricular nucleus (PVN). Diabetes was induced by a single intravenous injection of streptozotocin in rats. Acute experiments were carried out under anesthesia after 3 wk. The CSAR was evaluated by the responses of renal sympathetic nerve activity (RSNA) and mean arterial pressure (MAP) to epicardial application of capsaicin or bradykinin. Sympathetic activity and CSAR were enhanced in diabetic rats. Plasma norepinephrine and angiotensin II were increased, but the transient receptor potential vanilloid 1 (TRPV1) in the left ventricle wall was not significantly increased in diabetic rats. Pericardial injection of resiniferatoxin to desensitize cardiac afferents or PVN microinjection of lidocaine attenuated the CSAR and decreased the RSNA and MAP in diabetic rats. The AT1 receptor expression in the PVN increased in diabetic rats. Angiotensin II in the PVN caused greater increases in the RSNA and MAP and enhancement in the CSAR in diabetic rats, which were abolished by the losartan pretreatment. Losartan decreased the RSNA and MAP and attenuated the CSAR in diabetic rats but not in control rats. These results indicate that the CSAR is enhanced in the early stage of diabetic rats, which contributes to the sympathetic activation. AT1 receptors in the PVN are involved in the enhanced CSAR in diabetic rats.
Collapse
Affiliation(s)
- Lei Zhang
- Key Laboratory of Cardiovascular Disease and Molecular Intervention, Department of Physiology, Nanjing Medical University, Nanjing; and
| | - Xiao-Qing Xiong
- Key Laboratory of Cardiovascular Disease and Molecular Intervention, Department of Physiology, Nanjing Medical University, Nanjing; and
| | - Zhi-Dan Fan
- Department of Rheumatology and Immunology, Nanjing Children's Hospital Affiliated to Nanjing Medical University, Nanjing, China
| | - Xian-Bing Gan
- Key Laboratory of Cardiovascular Disease and Molecular Intervention, Department of Physiology, Nanjing Medical University, Nanjing; and
| | - Xing-Ya Gao
- Key Laboratory of Cardiovascular Disease and Molecular Intervention, Department of Physiology, Nanjing Medical University, Nanjing; and
| | - Guo-Qing Zhu
- Key Laboratory of Cardiovascular Disease and Molecular Intervention, Department of Physiology, Nanjing Medical University, Nanjing; and
| |
Collapse
|
33
|
Schwenke DO, Tokudome T, Kishimoto I, Horio T, Cragg PA, Shirai M, Kangawa K. One dose of ghrelin prevents the acute and sustained increase in cardiac sympathetic tone after myocardial infarction. Endocrinology 2012; 153:2436-43. [PMID: 22434083 DOI: 10.1210/en.2011-2057] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
Acute myocardial infarction (MI) increases sympathetic nerve activity (SNA) to the heart, which exacerbates chronic cardiac deterioration. The hormone ghrelin, if administered soon after an MI, prevents the increase in cardiac SNA and improves early survival prognosis. Whether these early beneficial effects of ghrelin also impact on cardiac function in chronic heart failure has not yet been addressed and thus was the aim of this study. MI was induced in Sprague Dawley rats by ligating the left coronary artery. One bolus of saline (n = 7) or ghrelin (150 μg/kg, sc, n = 9) was administered within 30 min of MI. Two weeks after the infarct (or sham; n = 7), rats were anesthetized and cardiac function was evaluated using a Millar pressure-volume conductance catheter. Cardiac SNA was measured using whole-nerve electrophysiological techniques. Untreated-MI rats had a high mortality rate (50%), evidence of severe cardiac dysfunction (ejection fraction 28%; P < 0.001), and SNA was significantly elevated (102% increase; P = 0.03). In comparison, rats that received a single dose of ghrelin after the MI tended to have a lower mortality rate (25%; P = NS) and no increase in SNA, and cardiac dysfunction was attenuated (ejection fraction of 43%; P = 0.014). This study implicates ghrelin as a potential clinical treatment for acute MI but also highlights the importance of therapeutic intervention in the early stages after acute MI. Moreover, these results uncover an intricate causal relationship between early and chronic changes in the neural control of cardiac function in heart failure.
Collapse
Affiliation(s)
- Daryl O Schwenke
- Department of Biochemistry, National Cerebral and Cardiovascular Center Research Institute, 5-7-1 Fujishirodai, Suita, Osaka 565-8565, Japan
| | | | | | | | | | | | | |
Collapse
|
34
|
Grande MT, Pascual G, Riolobos AS, Clemente-Lorenzo M, Bardaji B, Barreiro L, Tornavaca O, Meseguer A, López-Novoa JM. Increased oxidative stress, the renin-angiotensin system, and sympathetic overactivation induce hypertension in kidney androgen-regulated protein transgenic mice. Free Radic Biol Med 2011; 51:1831-41. [PMID: 21906672 DOI: 10.1016/j.freeradbiomed.2011.08.014] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/02/2011] [Revised: 08/16/2011] [Accepted: 08/18/2011] [Indexed: 01/07/2023]
Abstract
Gender differences in the incidence and severity of hypertension have suggested the involvement of a sex-dependent mechanism. Transgenic (Tg) mice overexpressing kidney androgen-regulated protein (KAP) specifically in kidney showed hypertension associated with oxidative stress. Reactive oxygen species (ROS) are strongly implicated in the pathological signaling leading to hypertension in a framework that includes renin-angiotensin system (RAS) activation, increased sympathetic activity, and cardiac remodeling. In this report, we observed that plasma levels of angiotensin II and catecholamines were increased in KAP Tg mice, compared with wild-type animals. Systemic administration of Tempol, a membrane-permeative superoxide dismutase mimetic, reduced arterial pressure as well as urinary excretion of oxidative stress markers and reduced both angiotensin II and norepinephrine plasma levels in KAP Tg mice. Intracerebroventricular administration of Tempol also reduced arterial pressure in Tg mice. Moreover, administration of apocynin and DPI, inhibitors of NADPH oxidase, a major source of ROS, also reduced arterial pressure and both angiotensin II and norepinephrine plasma levels in Tg mice. Thus, we analyzed the involvement of the RAS and sympathetic nervous system in KAP Tg mouse hypertension. Both captopril and losartan reduced arterial blood pressure in Tg mice, as also occurred after β-adrenergic blockade with atenolol. Also, intracerebroventricular losartan administration reduced arterial pressure in KAP Tg mice. Our data demonstrate that hypertension in male KAP Tg mice is based on increased oxidative stress, increased sympathetic activity, and RAS activation. Moreover, our results suggest a role for increased oxidative stress in the CNS as a major cause of hypertension in these animals.
Collapse
Affiliation(s)
- María T Grande
- Renal and Cardiovascular Physiopathology Unit, Departamento de Fisiología y Farmacología, Universidad de Salamanca, 37007 Salamanca, Spain
| | | | | | | | | | | | | | | | | |
Collapse
|
35
|
Gao J, Zhong MK, Fan ZD, Yuan N, Zhou YB, Zhang F, Gao XY, Zhu GQ. SOD1 overexpression in paraventricular nucleus improves post-infarct myocardial remodeling and ventricular function. Pflugers Arch 2011; 463:297-307. [PMID: 22006090 DOI: 10.1007/s00424-011-1036-0] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2011] [Revised: 09/23/2011] [Accepted: 09/28/2011] [Indexed: 02/07/2023]
Abstract
Excessive sympathetic activation contributes to the progression of chronic heart failure. Reactive oxygen species in paraventricular nucleus (PVN) play an important role in the enhanced sympathetic outflow. This study was designed to determine whether superoxide dismutase 1 (SOD1) overexpression in the PVN attenuated the sympathetic activation and cardiac dysfunction in rats after an episode of myocardial infarction (MI). Adenoviral vectors containing human SOD1 (Ad-SOD) or null adenoviral vectors (Ad-null) were immediately microinjected into the PVN of rats with coronary artery ligation or sham operation. At the eighth week, the SOD1 protein level and activity in the PVN increased while the superoxide anions in the PVN decreased in Ad-SOD rats. The SOD1 overexpression in the PVN prevented the increases in left ventricular end-diastolic pressure and volume, and the decreases in ejection fraction and peak velocities of contraction in MI rats. In addition, there was an attenuation of renal sympathetic nerve activity, cardiac sympathetic afferent reflex and plasma norepinephrine level in MI rats. Furthermore, the SOD1 overexpression in the PVN reduced cardiomyocyte size, collagen deposition and the TUNEL-positive cardiomyocytes in MI rats. These results indicate that the SOD1 overexpression in the PVN attenuates the excessive sympathetic activation, myocardial remodeling, cardiomyocyte apoptosis and ventricular dysfunction in MI rats.
Collapse
Affiliation(s)
- Juan Gao
- Department of Physiology, Nanjing Medical University, Nanjing, Jiangsu, 210029, China
| | | | | | | | | | | | | | | |
Collapse
|
36
|
Gan XB, Duan YC, Xiong XQ, Li P, Cui BP, Gao XY, Zhu GQ. Inhibition of cardiac sympathetic afferent reflex and sympathetic activity by baroreceptor and vagal afferent inputs in chronic heart failure. PLoS One 2011; 6:e25784. [PMID: 21991351 PMCID: PMC3185007 DOI: 10.1371/journal.pone.0025784] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2011] [Accepted: 09/09/2011] [Indexed: 11/19/2022] Open
Abstract
Background Cardiac sympathetic afferent reflex (CSAR) contributes to sympathetic activation and angiotensin II (Ang II) in paraventricular nucleus (PVN) augments the CSAR in vagotomized (VT) and baroreceptor denervated (BD) rats with chronic heart failure (CHF). This study was designed to determine whether it is true in intact (INT) rats with CHF and to determine the effects of cardiac and baroreceptor afferents on the CSAR and sympathetic activity in CHF. Methodology/Principal Findings Sham-operated (Sham) or coronary ligation-induced CHF rats were respectively subjected to BD+VT, VT, cardiac sympathetic denervation (CSD) or INT. Under anesthesia, renal sympathetic nerve activity (RSNA) and mean arterial pressure (MAP) were recorded, and the CSAR was evaluated by the RSNA and MAP responses to epicardial application of capsaicin. Either CSAR or the responses of RSNA, MAP and CSAR to Ang II in PVN were enhanced in CHF rats treated with BD+VT, VT or INT. Treatment with VT or BD+VT potentiated the CSAR and the CSAR responses to Ang II in both Sham and CHF rats. Treatment with CSD reversed the capsaicin-induced RSNA and MAP changes and the CSAR responses to Ang II in both Sham and CHF rats, and reduced the RSNA and MAP responses to Ang II only in CHF rats. Conclusions The CSAR and the CSAR responses to Ang II in PVN are enhanced in intact CHF rats. Baroreceptor and vagal afferent activities inhibit CSAR and the CSAR responses to Ang II in intact Sham and CHF rats.
Collapse
Affiliation(s)
- Xian-Bing Gan
- Department of Physiology, Nanjing Medical University, Nanjing, China
- Key Laboratory of Cardiovascular Disease and Molecular Intervention, Nanjing Medical University, Nanjing, China
| | - Yang-Can Duan
- Department of Physiology, Nanjing Medical University, Nanjing, China
- Department of Medical Ultrasound, Affiliated Hospital of Jining Medical University, Jining, China
| | - Xiao-Qing Xiong
- Department of Physiology, Nanjing Medical University, Nanjing, China
- Key Laboratory of Cardiovascular Disease and Molecular Intervention, Nanjing Medical University, Nanjing, China
| | - Peng Li
- Department of Physiology, Nanjing Medical University, Nanjing, China
| | - Bai-Ping Cui
- Department of Physiology, Nanjing Medical University, Nanjing, China
| | - Xing-Ya Gao
- Department of Physiology, Nanjing Medical University, Nanjing, China
| | - Guo-Qing Zhu
- Department of Physiology, Nanjing Medical University, Nanjing, China
- Key Laboratory of Cardiovascular Disease and Molecular Intervention, Nanjing Medical University, Nanjing, China
- * E-mail:
| |
Collapse
|
37
|
Shi Z, Gan XB, Fan ZD, Zhang F, Zhou YB, Gao XY, De W, Zhu GQ. Inflammatory cytokines in paraventricular nucleus modulate sympathetic activity and cardiac sympathetic afferent reflex in rats. Acta Physiol (Oxf) 2011; 203:289-97. [PMID: 21624097 DOI: 10.1111/j.1748-1716.2011.02313.x] [Citation(s) in RCA: 76] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
AIM This study was to determine the roles of inflammatory cytokines in paraventricular nucleus (PVN) in modulating sympathetic activity, blood pressure and cardiac sympathetic afferent reflex (CSAR). METHODS Renal sympathetic nerve activity (RSNA) and mean arterial pressure (MAP) were recorded in anaesthetized rats with bilateral sinoaortic denervation and vagotomy. The CSAR was evaluated by the RSNA response to epicardial application of bradykinin (BK). The levels of inflammatory cytokines were measured with ELISA. RESULTS The PVN microinjection of pro-inflammatory cytokines (PIC), tumour necrosis factor (TNF)-α or interleukin (IL)-1β, increased the baseline MAP and RSNA, and enhanced the CSAR. Anti-inflammatory cytokines (AIC), IL-4 or IL-13, in the PVN only increased the baseline MAP. In the rats pretreated with TNF-α or IL-1β but not in the rats pretreated with IL-4 or IL-13, sub-response dose of angiotensin II caused significant increases in the MAP and RSNA and enhancement in the CSAR. AT(1) receptor antagonist losartan in the PVN attenuated the effects of angiotensin II, TNF-α and IL-1β, but not the effects of IL-4 and IL-13. Stimulation of cardiac sympathetic afferents with epicardial application of BK increased the levels of TNF-α, IL-1β but not IL-4 in the PVN. CONCLUSION TNF-α or IL-1β in the PVN increases blood pressure and sympathetic outflow and enhances the CSAR, which is partially dependent on the AT(1) receptors, while IL-4 or IL-13 in the PVN only increases blood pressure. There is a synergetic effect of Ang II with TNF-α or IL-1β on blood pressure, sympathetic activity and CSAR.
Collapse
Affiliation(s)
- Z Shi
- Department of Physiology, Nanjing Medical University, China
| | | | | | | | | | | | | | | |
Collapse
|
38
|
Artificial microRNA interference targeting AT1a receptors in paraventricular nucleus attenuates hypertension in rats. Gene Ther 2011; 19:810-7. [DOI: 10.1038/gt.2011.145] [Citation(s) in RCA: 52] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
|
39
|
Xie J, Lu W, Gu R, Dai Q, Zong B, Ling L, Xu B. The impairment of ILK related angiogenesis involved in cardiac maladaptation after infarction. PLoS One 2011; 6:e24115. [PMID: 21949693 PMCID: PMC3174937 DOI: 10.1371/journal.pone.0024115] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2011] [Accepted: 08/01/2011] [Indexed: 12/22/2022] Open
Abstract
Background Integrin linked kinase (ILK), as an important component of mechanical stretch sensor, can initiate cellular signaling response in the heart when cardiac preload increases. Previous work demonstrated increased ILK expression could induce angiogenesis to improved heart function after MI. However the patholo-physiological role of ILK in cardiac remodeling after MI is not clear. Method and Results Hearts were induced to cardiac remodeling by infarction and studied in Sprague-Dawley rats. Until 4 weeks after infarction, ILK expression was increased in non-ischemic tissue in parallel with myocytes hypertrophy and compensatory cardiac function. 8 weeks later, when decompensation of heart function occurred, ILK level returned to baseline. Followed ILK alternation, vascular endothelial growth factor (VEGF) expression and phosphorylation of endothelial nitric oxide synthase (eNOS) was significantly decreased 8 weeks after MI. Histology study also showed significantly microvessel decreased and myocytes loss 8 weeks paralleled with ILK down-regualtion. While ILK expression was maintained by gene delivery, tissue angiogenesis and cardiac function was preserved during cardiac remodeling. Conclusion Temporally up-regulation of ILK level in non-ischemic myocytes by increased external load is associated with beneficial angiogenesis to maintain infarction-induced cardiac hypertrophy. When ILK expression returns to normal, this cardiac adaptive response for infarction is weaken. Understanding the ILK related mechanism of cardiac maladaptation leads to a new strategy for treatment of heart failure after infarction.
Collapse
Affiliation(s)
- Jun Xie
- Department of Cardiology, Drum Tower Hospital, Nanjing University Medical School, Nanjing, China
| | - Wen Lu
- Department of Cardiology, Drum Tower Hospital, Nanjing University Medical School, Nanjing, China
| | - Rong Gu
- Department of Cardiology, Drum Tower Hospital, Nanjing University Medical School, Nanjing, China
| | - Qin Dai
- Department of Cardiology, Drum Tower Hospital, Nanjing University Medical School, Nanjing, China
| | - Bin Zong
- Department of Cardiology, Drum Tower Hospital, Nanjing University Medical School, Nanjing, China
| | - Lin Ling
- Department of Cardiology, Drum Tower Hospital, Nanjing University Medical School, Nanjing, China
| | - Biao Xu
- Department of Cardiology, Drum Tower Hospital, Nanjing University Medical School, Nanjing, China
- * E-mail:
| |
Collapse
|
40
|
Xu Y, Gao Q, Gan XB, Chen L, Zhang L, Zhu GQ, Gao XY. Endogenous hydrogen peroxide in paraventricular nucleus mediates sympathetic activation and enhanced cardiac sympathetic afferent reflex in renovascular hypertensive rats. Exp Physiol 2011; 96:1282-92. [PMID: 21890522 DOI: 10.1113/expphysiol.2011.059733] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
An enhancement of the cardiac sympathetic afferent reflex (CSAR) contributes to sympathetic activation in renovascular hypertension. Angiotensin II in the paraventricular nucleus (PVN) augments the CSAR and increases sympathetic outflow and blood pressure. The present study aimed to determine whether endogenous hydrogen peroxide in the PVN mediated the enhanced CSAR, sympathetic activity and the effects of angiotensin II in the PVN in renovascular hypertension induced by the two-kidney, one-clip method (2K1C) in rats. At the end of the fourth week, the rats underwent sino-aortic and vagal denervation under general anaesthesia with urethane and α-chloralose. Renal sympathetic nerve activity (RSNA) and mean arterial pressure (MAP) were recorded. The CSAR was evaluated by the RSNA response to epicardial application of bradykinin. Microinjection of polyethylene glycol-catalase (PEG-CAT), an analogue of endogenous catalase, into the PVN decreased the RSNA and MAP and abolished the CSAR in both sham-operated and 2K1C rats. Microinjection into the PVN of the catalase inhibitor, aminotriazole, increased the RSNA and MAP and enhanced the CSAR. The effects of PEG-CAT or aminotriazole were greater in 2K1C rats than in sham-operated animals. The effects of angiotensin II in the PVN were abolished by pretreatment with PEG-CAT in both sham-operated and 2K1C rats; however, aminotriazole failed to potentiate the effects of angiotensin II. The catalase activity was decreased but the H(2)O(2) levels were increased in the PVN of 2K1C rats. These results indicate that endogenous H(2)O(2) in the PVN not only mediates the enhanced sympathetic activity and CSAR, but also the effects of angiotensin II in the PVN in renovascular hypertensive rats.
Collapse
Affiliation(s)
- Yao Xu
- Department of Physiology, Nanjing Medical University, Nanjing 210029, China
| | | | | | | | | | | | | |
Collapse
|
41
|
Effects of anthocyanins on blood pressure and stress reactivity: a double-blind randomized placebo-controlled crossover study. J Hum Hypertens 2011; 26:396-404. [PMID: 21544087 DOI: 10.1038/jhh.2011.41] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
High intakes of flavonoids are associated with reduced cardiovascular risk, and flavonoids such as cocoa and soy protein isolate have shown beneficial effects on blood pressure (BP). Anthocyanins constitute a flavonoid subgroup consumed in regular diets, but few studies have assessed the antihypertensive potential of anthocyanins. We aimed to assess whether high concentrations of relatively pure anthocyanins reduce BP and alter cardiovascular and catecholamine reactivity to stress. A total of 31 healthy men between 35-51 years of age with screening BP >140/90 mm Hg, not on antihypertensive or lipid-lowering medication, were randomised in a double-blind crossover study to placebo versus 320-mg anthoycanins twice daily. Treatment duration was 4 weeks, with a 4-week washout. Sitting and supine BP measurements, ambulatory BP recording and stress reactivity were assessed and analyzed by a paired sample t-test. In all, 27 patients completed all visits. Sitting systolic BP (primary endpoint) was 133 mm Hg after placebo versus 135 mm Hg after anthocyanin treatment (P=0.25). Anthocyanins did neither affect semiautomatic oscillometric BP measurements in the sitting or supine position nor 24-h ambulatory BP. No significant differences in stress reactivity were found across treatment periods. Overall, we conclude that high concentrations of these relatively pure anthocyanins do not reduce BP in healthy men with a high normal BP.
Collapse
|
42
|
Chen AD, Zhang SJ, Yuan N, Xu Y, De W, Gao XY, Zhu GQ. Angiotensin AT1receptors in paraventricular nucleus contribute to sympathetic activation and enhanced cardiac sympathetic afferent reflex in renovascular hypertensive rats. Exp Physiol 2011; 96:94-103. [DOI: 10.1113/expphysiol.2010.054353] [Citation(s) in RCA: 60] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
|