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Shen G, Sanchez K, Hu S, Zhao Z, Zhang L, Ma Q. 3D doppler ultrasound imaging of cerebral blood flow for assessment of neonatal hypoxic-ischemic brain injury in mice. PLoS One 2023; 18:e0285434. [PMID: 37159455 PMCID: PMC10168578 DOI: 10.1371/journal.pone.0285434] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2023] [Accepted: 04/21/2023] [Indexed: 05/11/2023] Open
Abstract
Cerebral blood flow (CBF) acutely reduces in neonatal hypoxic-ischemic encephalopathy (HIE). Clinic studies have reported that severe CBF impairment can predict HIE outcomes in neonates. Herein, the present study uses a non-invasive 3D ultrasound imaging approach to evaluate the changes of CBF after HI insult, and explores the correlation between CBF alterations and HI-induced brain infarct in mouse pups. The neonatal HI brain injury was induced in postnatal day 7 mouse pups using the Rice-Vannucci model. Non-invasive 3D ultrasound imaging was conducted to image CBF changes with multiple frequencies on mouse pups before common carotid artery (CCA) ligation, immediately after ligation, and 0 or 24 hours after HI. Vascularity ratio of the ipsilateral hemisphere was acutely reduced after unilateral ligation of the CCA alone or in combination with hypoxia, and partially restored at 24 hours after HI. Moreover, regression analysis showed that the vascularity ratio of ipsilateral hemisphere was moderately correlated with brain infarct size 24 hours after HI, indicating that CBF reduction contributes to of HI brain injury. To further verify the association between CBF and HI-induced brain injury, a neuropeptide C-type natriuretic peptide (CNP) or PBS was intranasally administrated to the brain of mouse pups one hour after HI insult. Brain infarction, CBF imaging and long-term neurobehavioral tests were conducted. The result showed that intranasal administration of CNP preserved ipsilateral CBF, reduced the infarct size, and improved neurological function after HI brain injury. Our findings suggest that CBF alteration is an indicator for neonatal HI brain injury, and 3D ultrasound imaging is a useful non-invasive approach for assessment of HI brain injury in mouse model.
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Affiliation(s)
- Guofang Shen
- Department of Basic Sciences, The Lawrence D. Longo, MD Center for Perinatal Biology, Loma Linda University School of Medicine, Loma Linda, CA, United States of America
- Department of Hematologic Malignancies Translational Science, Beckman Research Institute of City of Hope, Duarte, CA, United States of America
| | - Kayla Sanchez
- Department of Basic Sciences, The Lawrence D. Longo, MD Center for Perinatal Biology, Loma Linda University School of Medicine, Loma Linda, CA, United States of America
| | - Shirley Hu
- Department of Basic Sciences, The Lawrence D. Longo, MD Center for Perinatal Biology, Loma Linda University School of Medicine, Loma Linda, CA, United States of America
| | - Zhen Zhao
- Zilkha Neurogenetic Institute and Department of Physiology and Neuroscience, Center for Neurodegeneration and Regeneration, Keck School of Medicine, University of Southern California, Los Angeles, CA, United States of America
| | - Lubo Zhang
- Department of Basic Sciences, The Lawrence D. Longo, MD Center for Perinatal Biology, Loma Linda University School of Medicine, Loma Linda, CA, United States of America
| | - Qingyi Ma
- Department of Basic Sciences, The Lawrence D. Longo, MD Center for Perinatal Biology, Loma Linda University School of Medicine, Loma Linda, CA, United States of America
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Belemnaba L, Nitiéma M, Ilboudo S, Ouédraogo GG, Ouédraogo N, Belemlilga MB, Compaoré S, Ouédraogo S, Ouédraogo S. Preclinical Evaluation of the Antihypertensive Effect of an Aqueous Extract of Anogeissus leiocarpa (DC) Guill et Perr. Bark of Trunk in L-NAME-Induced Hypertensive Rat. J Exp Pharmacol 2021; 13:739-754. [PMID: 34393522 PMCID: PMC8357407 DOI: 10.2147/jep.s319787] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2021] [Accepted: 07/19/2021] [Indexed: 12/22/2022] Open
Abstract
BACKGROUND The present study investigates the effect of an aqueous extract of Anogeissus leiocarpa (AEAL) on normotensive Wistar rats and its chronic antihypertensive effects in L-NAME-induced hypertensive rats by using a non-invasive tail-cuff model. METHODS The effects of AEAL (50mg/kg) and NaCl 0.9% on blood pressure were investigated by daily oral administration in normotensive Wistar rats over four weeks. L-NAME-induced hypertensive rats were produced by L-NAME (40mg/kg) daily oral administration for two weeks. For chronic antihypertensive effects, induced hypertensive rats have received L-NAME in combination with AEAL (10 or 50mg/kg/day) for two following weeks. RESULTS In normotensive rats, daily administration of AEAL (50mg/kg) has no significant effect on their blood pressure, which was similar to that of the control group. L-NAME's daily oral administration induces a progressive increase in systolic blood pressure (SBP) from 115.8 ± 7.9mmHg to 153.5 ± 4.6mmHg after two weeks, which was maintained to the end of the treatment. In L-NAME-induced hypertensive rats, AEAL (50mg/kg/day) significantly decreases the SPB from 160.0 ± 5.8 mmHg to 108.8 ± 2.7mmHg after only four days of administration. However, the lower dose of AEAL (10mg/kg) also normalized the SBP of L-NAME-induced hypertensive rats but only evident after seven days of administration. Moreover, AEAL does not effect on the serum biochemical parameters (ALAT, ASAT, CREAT, etc.) and any macroscopic adverse effect was detected on the sensible organs involved during hypertension. In the aorta rings from treated rats, AEAL (50mg/kg/day) alone or in combination with L-NAME has enhanced the vasodilation effect of acetylcholine. However, the vasodilation effect of AEAL alone or in association with L-NAME has enhanced the sodium nitroprusside effect in treated rat aorta rings after autopsy. CONCLUSION These findings suggest that AEAL affords significant antihypertensive effects against L-NAME-induced hypertensive rats without modification of serum parameters and deleterious effects.
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Affiliation(s)
- Lazare Belemnaba
- Institut de Recherche en Sciences de la Santé/Centre National de la Recherche Scientifique et Technologique (IRSS/CNRST), 03 BP 7047, Ouagadougou, 03, Burkina Faso
| | - Mathieu Nitiéma
- Institut de Recherche en Sciences de la Santé/Centre National de la Recherche Scientifique et Technologique (IRSS/CNRST), 03 BP 7047, Ouagadougou, 03, Burkina Faso
| | - Sylvain Ilboudo
- Institut de Recherche en Sciences de la Santé/Centre National de la Recherche Scientifique et Technologique (IRSS/CNRST), 03 BP 7047, Ouagadougou, 03, Burkina Faso
| | - Gueswindé Geoffroy Ouédraogo
- Institut de Recherche en Sciences de la Santé/Centre National de la Recherche Scientifique et Technologique (IRSS/CNRST), 03 BP 7047, Ouagadougou, 03, Burkina Faso
| | - Noufou Ouédraogo
- Institut de Recherche en Sciences de la Santé/Centre National de la Recherche Scientifique et Technologique (IRSS/CNRST), 03 BP 7047, Ouagadougou, 03, Burkina Faso
| | - Mohamed Bonewendé Belemlilga
- Institut de Recherche en Sciences de la Santé/Centre National de la Recherche Scientifique et Technologique (IRSS/CNRST), 03 BP 7047, Ouagadougou, 03, Burkina Faso
| | - Souleymane Compaoré
- Institut de Recherche en Sciences de la Santé/Centre National de la Recherche Scientifique et Technologique (IRSS/CNRST), 03 BP 7047, Ouagadougou, 03, Burkina Faso
- Université Joseph KI-ZERBO, 03 BP 7021, Ouagadougou, 03, Burkina Faso
| | - Salfo Ouédraogo
- Institut de Recherche en Sciences de la Santé/Centre National de la Recherche Scientifique et Technologique (IRSS/CNRST), 03 BP 7047, Ouagadougou, 03, Burkina Faso
- Université Joseph KI-ZERBO, 03 BP 7021, Ouagadougou, 03, Burkina Faso
| | - Sylvin Ouédraogo
- Institut de Recherche en Sciences de la Santé/Centre National de la Recherche Scientifique et Technologique (IRSS/CNRST), 03 BP 7047, Ouagadougou, 03, Burkina Faso
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Obesity-associated cardiovascular risk in women: hypertension and heart failure. Clin Sci (Lond) 2021; 135:1523-1544. [PMID: 34160010 DOI: 10.1042/cs20210384] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2021] [Revised: 05/14/2021] [Accepted: 06/07/2021] [Indexed: 02/07/2023]
Abstract
The pathogenesis of obesity-associated cardiovascular diseases begins long prior to the presentation of a cardiovascular event. In both men and women, cardiovascular events, and their associated hospitalizations and mortality, are often clinically predisposed by the presentation of a chronic cardiovascular risk factor. Obesity increases the risk of cardiovascular diseases in both sexes, however, the clinical prevalence of obesity, as well as its contribution to crucial cardiovascular risk factors is dependent on sex. The mechanisms via which obesity leads to cardiovascular risk is also discrepant in women between their premenopausal, pregnancy and postmenopausal phases of life. Emerging data indicate that at all reproductive statuses and ages, the presentation of a cardiovascular event in obese women is strongly associated with hypertension and its subsequent chronic risk factor, heart failure with preserved ejection fraction (HFpEF). In addition, emerging evidence indicates that obesity increases the risk of both hypertension and heart failure in pregnancy. This review will summarize clinical and experimental data on the female-specific prevalence and mechanisms of hypertension and heart failure in women across reproductive stages and highlight the particular risks in pregnancy as well as emerging data in a high-risk ethnicity in women of African ancestry (AA).
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Cardiac morphological and functional changes induced by C-type natriuretic peptide are different in normotensive and spontaneously hypertensive rats. J Hypertens 2021; 38:2305-2317. [PMID: 32649642 DOI: 10.1097/hjh.0000000000002570] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
OBJECTIVE Inflammation and fibrosis are key mechanisms in cardiovascular remodeling. C-type natriuretic peptide (CNP) is an endothelium-derived factor with a cardiovascular protective role, although its in-vivo effect on cardiac remodeling linked to hypertension has not been investigated. The aim of this study was to determine the effects of chronic administration of CNP on inflammatory and fibrotic cardiac mechanisms in normotensive Wistar rats and spontaneously hypertensive rats (SHR). METHODS Twelve-week-old male SHR and normotensive rats were infused with CNP (0.75 μg/h/100 g) or isotonic saline (NaCl 0.9%) for 14 days (subcutaneous micro-osmotic pumps). Echocardiograms and electrocardiograms were performed, and SBP was measured. After treatment, transforming growth factor-beta 1, Smad proteins, tumor necrosis factor-alpha, interleukin-1 and interleukin-6, nitric oxide (NO) system and 2-thiobarbituric acid-reactive substances were evaluated in left ventricle. Histological studies were also performed. RESULTS SHR showed lower cardiac output with signs of fibrosis and hypertrophy in left ventricle, higher NO-system activity and more oxidative damage, as well as higher pro-inflammatory and pro-fibrotic markers than normotensive rats. Chronic CNP treatment-attenuated hypertension and ventricular hypertrophy in SHR, with no changes in normotensive rats. In left ventricle, CNP induced an anti-inflammatory and antifibrotic response, decreasing both pro-fibrotic and pro-inflammatory cytokines in SHR. In addition, CNP reduced oxidative damage as well as collagen content, and upregulated the NO system in both groups. CONCLUSION Chronic CNP treatment appears to attenuate hypertension and associated end-organ damage in the heart by reducing inflammation and fibrosis.
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C-type natriuretic peptide-induced relaxation through cGMP-dependent protein kinase and SERCA activation is impaired in two kidney-one clip rat aorta. Life Sci 2021; 272:119223. [PMID: 33610574 DOI: 10.1016/j.lfs.2021.119223] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2020] [Revised: 01/28/2021] [Accepted: 02/09/2021] [Indexed: 11/22/2022]
Abstract
AIMS Hypertension underlies endothelial dysfunction, and activation of vasorelaxation signaling with low dependence on nitric oxide (NO) represents a good alternative for vascular modulation. C-type natriuretic peptide (CNP) causes relaxation by increasing cyclic guanosine 3',5'-monophosphate (cGMP) or Gi-protein activation through its natriuretic peptide receptor-B or -C, respectively. We have hypothesized that CNP could exerts its effects and could overcome endothelial dysfunction in two kidney-one clip (2K-1C) hypertensive rat aorta. Here, we investigate the intracellular signaling involved in CNP effects in hypertension. MATERIALS AND METHODS The 2K-1C hypertension was induced in male Wistar rats (200 g). CNP-induced vascular relaxation and cGMP production were investigated in rat thoracic aortas. The natriuretic peptide receptor-B and -C localization was evaluated by immunofluorescence. Calcium mobilization was assessed in endothelial cells from rat aortas. KEY FINDINGS CNP induced similar relaxation in normotensive and 2K-1C hypertensive rat aortas, which increased after endothelium removal. CNP-induced relaxation involved natriuretic peptide receptor-B and -C activation in 2K-1C rats. Nitric oxide synthase (NOS) and soluble guanylyl cyclase (sGC) counter-regulated CNP-particulate GC (pGC) activation in aortas. CNP reduced endothelial calcium and increased cGMP production, which was lower in 2K-1C. CNP-induced cGMP-dependent protein kinase (PKG) and sarcoplasmic/endoplasmic reticulum Ca2+-ATPase (SERCA) activation was impaired in 2K-1C rat aorta. SIGNIFICANCE Our results indicated CNP triggered relaxation through its natriuretic peptide receptor-B and -C in 2K-1C rat aortas, and that CNP-induced relaxation overcomes endothelial dysfunction in hypertension. In addition, NOS and sGC activities counter-regulate CNP-pGC activation to induce vascular relaxation.
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Faulkner JL, Harwood D, Kennard S, Antonova G, Clere N, Belin de Chantemèle EJ. Dietary sodium restriction sex specifically impairs endothelial function via mineralocorticoid receptor-dependent reduction in NO bioavailability in Balb/C mice. Am J Physiol Heart Circ Physiol 2021; 320:H211-H220. [PMID: 33095056 PMCID: PMC7847080 DOI: 10.1152/ajpheart.00413.2020] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/02/2020] [Revised: 10/20/2020] [Accepted: 10/20/2020] [Indexed: 12/17/2022]
Abstract
Recent findings from our group demonstrated that females exhibit higher endothelial mineralocorticoid receptor (MR) expression than males, which predisposes them to aldosterone-mediated endothelial dysfunction in the context of metabolic disorders. However, whether the endothelium of female mice presents a higher propensity to MR-mediated dysfunction than that of males in the absence of comorbidities remains unknown. We therefore sought to investigate whether increasing aldosterone production endogenously with sodium restriction impairs endothelial function in otherwise healthy female mice. We fed male and female Balb/C mice a normal (0.4% NaCl; NSD) or sodium-restricted diet (0.05% NaCl; SRD) for 4 wk. Females exhibited higher baseline endothelial function (relaxation to acetylcholine) and lower vascular contractility (constriction to phenylephrine, serotonin, and KCl). However, SRD impaired endothelial-dependent relaxation and increased vascular contractility in female mice, effectively ablating the baseline sex difference. Female sex also increased baseline adrenal CYP11B2 expression; however, SRD significantly enhanced CYP11B2 expression in male and female mice and ablated the sex difference. Nitric oxide synthase (NOS) inhibition with Nω-nitro-l-arginine methyl ester hydrochloride eliminated both sex as well as diet-induced differences in endothelial dysfunction. In accordance, females demonstrated higher vascular endothelial NOS expression at baseline, which SRD significantly decreased. In addition, SRD diminished vascular NOX4 expression in female mice only. MR blockade with spironolactone-protected female mice from decreases in endothelial-dependent relaxation but not increases in vascular contractility. Utilizing sodium restriction as a method to increase plasma aldosterone levels in healthy female mice, we demonstrated that female mice are more susceptible to vascular damage via MR activation in the vascular endothelium only.NEW & NOTEWORTHY Female sex confers improved endothelial relaxation and vascular constriction responses in female Balb/C mice compared with males under baseline conditions. Sodium restriction impairs endothelial function, which is nitric oxide dependent, and increases vascular contractility in association with reduced vascular endothelial nitric oxide synthase and NOX4 expression in female mice ablating the baseline sex difference. Mineralocorticoid receptor antagonism ablates sodium restriction-induced endothelial dysfunction, but not increased vascular contractility, in female mice.
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Affiliation(s)
- Jessica L Faulkner
- Vascular Biology Center, Medical College of Georgia at Augusta University, Augusta, Georgia
| | - Daisy Harwood
- Vascular Biology Center, Medical College of Georgia at Augusta University, Augusta, Georgia
| | - Simone Kennard
- Vascular Biology Center, Medical College of Georgia at Augusta University, Augusta, Georgia
| | - Galina Antonova
- Vascular Biology Center, Medical College of Georgia at Augusta University, Augusta, Georgia
| | - Nicolas Clere
- Micro and Nanomédecines Translationelles-MINT, UNIV Angers, INSERM U1066, CNRS UMR 6021, Université Bretagne Loire, Angers, France
| | - Eric J Belin de Chantemèle
- Vascular Biology Center, Medical College of Georgia at Augusta University, Augusta, Georgia
- Department of Cardiology, Medical College of Georgia at Augusta University, Augusta, Georgia
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Korshunov VA, Smolock EM, Wines-Samuelson ME, Faiyaz A, Mickelsen DM, Quinn B, Pan C, Dugbartey GJ, Yan C, Doyley MM, Lusis AJ, Berk BC. Natriuretic Peptide Receptor 2 Locus Contributes to Carotid Remodeling. J Am Heart Assoc 2020; 9:e014257. [PMID: 32394795 PMCID: PMC7660849 DOI: 10.1161/jaha.119.014257] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Background Carotid artery intima/media thickness (IMT) is a hallmark trait associated with future cardiovascular events. The goal of this study was to map new genes that regulate carotid IMT by genome-wide association. Methods and Results We induced IMT by ligation procedure of the left carotid artery in 30 inbred mouse strains. Histologic reconstruction revealed significant variation in left carotid artery intima, media, adventitia, external elastic lamina volumes, intima-to-media ratio, and (intima+media)/external elastic lamina percent ratio in inbred mice. The carotid remodeling trait was regulated by distinct genomic signatures with a dozen common single-nucleotide polymorphisms associated with left carotid artery intima volume, intima-to-media ratio, and (intima+media)/external elastic lamina percent ratio. Among genetic loci on mouse chromosomes 1, 4, and 12, there was natriuretic peptide receptor 2 (Npr2), a strong candidate gene. We observed that only male, not female, mice heterozygous for a targeted Npr2 deletion (Npr2+/-) exhibited defective carotid artery remodeling compared with Npr2 wild-type (Npr2+/+) littermates. Fibrosis in carotid IMT was significantly increased in Npr2+/- males compared with Npr2+/- females or Npr2+/+ mice. We also detected decreased Npr2 expression in human atherosclerotic plaques, similar to that seen in studies in Npr2+/- mice. Conclusions We found that components of carotid IMT were regulated by distinct genetic factors. We also showed a critical role for Npr2 in genetic regulation of vascular fibrosis associated with defective carotid remodeling.
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Affiliation(s)
| | - Elaine M Smolock
- Department of Medicine Aab Cardiovascular Research Institute Rochester NY
| | | | - Abrar Faiyaz
- Department of Electrical & Computer Engineering University of Rochester and Hajim School of Engineering & Applied Sciences Rochester NY
| | - Deanne M Mickelsen
- Department of Medicine Aab Cardiovascular Research Institute Rochester NY
| | - Breandan Quinn
- Department of Medicine Aab Cardiovascular Research Institute Rochester NY
| | - Calvin Pan
- Department of Medicine David Geffen School of Medicine University of California Los Angeles Los Angeles CA
| | - George J Dugbartey
- Department of Medicine Aab Cardiovascular Research Institute Rochester NY
| | - Chen Yan
- Department of Medicine Aab Cardiovascular Research Institute Rochester NY
| | - Marvin M Doyley
- Department of Electrical & Computer Engineering University of Rochester and Hajim School of Engineering & Applied Sciences Rochester NY
| | - Aldons J Lusis
- Department of Medicine David Geffen School of Medicine University of California Los Angeles Los Angeles CA
| | - Bradford C Berk
- Department of Medicine Aab Cardiovascular Research Institute Rochester NY.,University of Rochester Neurorestoration Institute University of Rochester School of Medicine and Dentistry Rochester NY
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Itakura R, Inoue Y, Ogawa K, Nagoshi T, Minai K, Ogawa T, Kawai M, Yoshimura M. A Highly-sensitized Response of B-type Natriuretic Peptide to Cardiac Ischaemia Quantified by Intracoronary Pressure Measurements. Sci Rep 2020; 10:2403. [PMID: 32051484 PMCID: PMC7015889 DOI: 10.1038/s41598-020-59309-4] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2018] [Accepted: 01/27/2020] [Indexed: 01/15/2023] Open
Abstract
B-type natriuretic peptide (BNP) secretion is stimulated by cardiac dysfunction. However, it is unclear how finely myocardial ischaemia contributes to BNP secretion and whether increases in BNP secretion contribute to coronary vasodilation. This study investigated the direct interaction between plasma BNP levels and cardiac ischaemia using the baseline distal-to-aortic pressure ratio (Pd/Pa). We examined the baseline Pd/Pa and fractional flow reserve (FFR) in 167 patients with intermediate coronary stenosis. The plasma BNP level appeared to be associated with the baseline Pd/Pa in the study population, and this association appeared to become clear only in patients with an FFR ≤ 0.80. To examine the effect of the baseline Pd/Pa on the BNP level in these patients, structural equation modeling (SEM) was performed. The baseline Pd/Pa significantly affected the BNP level (β: -0.37, p = 0.003) and the left ventricular ejection fraction (β: 0.43, p = 0.001). To examine the role of BNP in coronary vasodilation, we proposed another path model using a novel value obtained by dividing the FFR by the baseline Pd/Pa (FFR/baseline Pd/Pa) as an index of the hyperaemic response. The BNP level significantly affected the FFR/baseline Pd/Pa (β: 0.48, p = 0.037). This study demonstrated that BNP finely responded to an exacerbation of cardiac ischaemia and that increases in BNP secretion effectively ameliorated coronary vasoconstriction.
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Affiliation(s)
- Ryosuke Itakura
- Division of Cardiology, Department of Internal Medicine, The Jikei University School of Medicine, 3-25-8 Nishi-shinbashi, Minato-ku, Tokyo, 105-8461, Japan
| | - Yasunori Inoue
- Division of Cardiology, Department of Internal Medicine, The Jikei University School of Medicine, 3-25-8 Nishi-shinbashi, Minato-ku, Tokyo, 105-8461, Japan.
| | - Kazuo Ogawa
- Division of Cardiology, Department of Internal Medicine, The Jikei University School of Medicine, 3-25-8 Nishi-shinbashi, Minato-ku, Tokyo, 105-8461, Japan
| | - Tomohisa Nagoshi
- Division of Cardiology, Department of Internal Medicine, The Jikei University School of Medicine, 3-25-8 Nishi-shinbashi, Minato-ku, Tokyo, 105-8461, Japan
| | - Kosuke Minai
- Division of Cardiology, Department of Internal Medicine, The Jikei University School of Medicine, 3-25-8 Nishi-shinbashi, Minato-ku, Tokyo, 105-8461, Japan
| | - Takayuki Ogawa
- Division of Cardiology, Department of Internal Medicine, The Jikei University School of Medicine, 3-25-8 Nishi-shinbashi, Minato-ku, Tokyo, 105-8461, Japan
| | - Makoto Kawai
- Division of Cardiology, Department of Internal Medicine, The Jikei University School of Medicine, 3-25-8 Nishi-shinbashi, Minato-ku, Tokyo, 105-8461, Japan
| | - Michihiro Yoshimura
- Division of Cardiology, Department of Internal Medicine, The Jikei University School of Medicine, 3-25-8 Nishi-shinbashi, Minato-ku, Tokyo, 105-8461, Japan
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Špiranec K, Chen W, Werner F, Nikolaev VO, Naruke T, Koch F, Werner A, Eder-Negrin P, Diéguez-Hurtado R, Adams RH, Baba HA, Schmidt H, Schuh K, Skryabin BV, Movahedi K, Schweda F, Kuhn M. Endothelial C-Type Natriuretic Peptide Acts on Pericytes to Regulate Microcirculatory Flow and Blood Pressure. Circulation 2019; 138:494-508. [PMID: 29626067 DOI: 10.1161/circulationaha.117.033383] [Citation(s) in RCA: 88] [Impact Index Per Article: 17.6] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
BACKGROUND Peripheral vascular resistance has a major impact on arterial blood pressure levels. Endothelial C-type natriuretic peptide (CNP) participates in the local regulation of vascular tone, but the target cells remain controversial. The cGMP-producing guanylyl cyclase-B (GC-B) receptor for CNP is expressed in vascular smooth muscle cells (SMCs). However, whereas endothelial cell-specific CNP knockout mice are hypertensive, mice with deletion of GC-B in vascular SMCs have unaltered blood pressure. METHODS We analyzed whether the vasodilating response to CNP changes along the vascular tree, ie, whether the GC-B receptor is expressed in microvascular types of cells. Mice with a floxed GC-B ( Npr2) gene were interbred with Tie2-Cre or PDGF-Rβ-Cre ERT2 lines to develop mice lacking GC-B in endothelial cells or in precapillary arteriolar SMCs and capillary pericytes. Intravital microscopy, invasive and noninvasive hemodynamics, fluorescence energy transfer studies of pericyte cAMP levels in situ, and renal physiology were combined to dissect whether and how CNP/GC-B/cGMP signaling modulates microcirculatory tone and blood pressure. RESULTS Intravital microscopy studies revealed that the vasodilatatory effect of CNP increases toward small-diameter arterioles and capillaries. CNP consistently did not prevent endothelin-1-induced acute constrictions of proximal arterioles, but fully reversed endothelin effects in precapillary arterioles and capillaries. Here, the GC-B receptor is expressed both in endothelial and mural cells, ie, in pericytes. It is notable that the vasodilatatory effects of CNP were preserved in mice with endothelial GC-B deletion, but abolished in mice lacking GC-B in microcirculatory SMCs and pericytes. CNP, via GC-B/cGMP signaling, modulates 2 signaling cascades in pericytes: it activates cGMP-dependent protein kinase I to phosphorylate downstream targets such as the cytoskeleton-associated vasodilator-activated phosphoprotein, and it inhibits phosphodiesterase 3A, thereby enhancing pericyte cAMP levels. These pathways ultimately prevent endothelin-induced increases of pericyte calcium levels and pericyte contraction. Mice with deletion of GC-B in microcirculatory SMCs and pericytes have elevated peripheral resistance and chronic arterial hypertension without a change in renal function. CONCLUSIONS Our studies indicate that endothelial CNP regulates distal arteriolar and capillary blood flow. CNP-induced GC-B/cGMP signaling in microvascular SMCs and pericytes is essential for the maintenance of normal microvascular resistance and blood pressure.
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Affiliation(s)
- Katarina Špiranec
- Institute of Physiology, University of Würzburg and Comprehensive Heart Failure Center, University Hospital Würzburg, Germany (K. Špiranec, W.C., S.C., F.W., T.N., F.K., P.E.-N., K. Schuh, M.K.)
| | - Wen Chen
- Institute of Physiology, University of Würzburg and Comprehensive Heart Failure Center, University Hospital Würzburg, Germany (K. Špiranec, W.C., S.C., F.W., T.N., F.K., P.E.-N., K. Schuh, M.K.)
| | - Franziska Werner
- Institute of Physiology, University of Würzburg and Comprehensive Heart Failure Center, University Hospital Würzburg, Germany (K. Špiranec, W.C., S.C., F.W., T.N., F.K., P.E.-N., K. Schuh, M.K.)
| | - Viacheslav O Nikolaev
- Institute of Experimental Cardiovascular Research, University Medical Center Hamburg-Eppendorf, Germany (V.O.N.)
| | - Takashi Naruke
- Institute of Physiology, University of Würzburg and Comprehensive Heart Failure Center, University Hospital Würzburg, Germany (K. Špiranec, W.C., S.C., F.W., T.N., F.K., P.E.-N., K. Schuh, M.K.)
| | - Franziska Koch
- Institute of Physiology, University of Würzburg and Comprehensive Heart Failure Center, University Hospital Würzburg, Germany (K. Špiranec, W.C., S.C., F.W., T.N., F.K., P.E.-N., K. Schuh, M.K.)
| | - Andrea Werner
- Institute of Physiology, University of Regensburg, Germany (A.W., F.S.)
| | - Petra Eder-Negrin
- Institute of Physiology, University of Würzburg and Comprehensive Heart Failure Center, University Hospital Würzburg, Germany (K. Špiranec, W.C., S.C., F.W., T.N., F.K., P.E.-N., K. Schuh, M.K.)
| | - Rodrigo Diéguez-Hurtado
- Max-Planck-Institute for Molecular Biomedicine, Department of Tissue Morphogenesis (R.D.-H., R.H.A.)
| | - Ralf H Adams
- Max-Planck-Institute for Molecular Biomedicine, Department of Tissue Morphogenesis (R.D.-H., R.H.A.)
| | - Hideo A Baba
- Faculty of Medicine, University of Münster, Germany. Institute of Pathology, University Hospital Essen, University Duisburg-Essen, Germany (H.A.B.)
| | - Hannes Schmidt
- Interfaculty Institute of Biochemistry, University of Tübingen, Germany (H.S.)
| | - Kai Schuh
- Institute of Physiology, University of Würzburg and Comprehensive Heart Failure Center, University Hospital Würzburg, Germany (K. Špiranec, W.C., S.C., F.W., T.N., F.K., P.E.-N., K. Schuh, M.K.)
| | - Boris V Skryabin
- Core Facility Transgenic Animal and genetic engineering Models (B.V.S.)
| | - Kiavash Movahedi
- Myeloid Cell Immunology Lab, Vesalius Research Center, Center for Inflammation Research, and Laboratory of Cellular and Molecular Immunology, Vrije Universiteit Brussel, Brussels, Belgium (K.M.)
| | - Frank Schweda
- Institute of Physiology, University of Regensburg, Germany (A.W., F.S.)
| | - Michaela Kuhn
- Institute of Physiology, University of Würzburg and Comprehensive Heart Failure Center, University Hospital Würzburg, Germany (K. Špiranec, W.C., S.C., F.W., T.N., F.K., P.E.-N., K. Schuh, M.K.)
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10
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Faulkner JL, Belin de Chantemèle EJ. Mineralocorticoid Receptor and Endothelial Dysfunction in Hypertension. Curr Hypertens Rep 2019; 21:78. [PMID: 31485760 DOI: 10.1007/s11906-019-0981-4] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
PURPOSE OF REVIEW To review the latest reports of the contributions of the endothelial mineralocorticoid receptor to endothelial dysfunction and hypertension to begin to determine the clinical potential for this pathway for hypertension treatment. RECENT FINDINGS Endothelial mineralocorticoid receptor expression is sex-specifically increased in female mice and humans compared with males. Moreover, the expression of endothelial mineralocorticoid receptors is increased by endothelial progesterone receptor activation and naturally occurring fluctuations in progesterone levels (estrous, pregnancy) predict endothelial mineralocorticoid receptor expression levels in female mice. These data follow many previous reports that have indicated that endothelial mineralocorticoid receptor deletion is protective in the development of obesity- and diabetes-associated endothelial dysfunction in female mouse models. These studies have more recently been followed up by reports indicating that both intact endothelial mineralocorticoid receptor and progesterone receptor expression are required for obesity-associated, leptin-mediated endothelial dysfunction in female mice. In addition, the intra-endothelial signaling pathway for endothelial mineralocorticoid receptors to induce dysfunction requires the intact expression of α-epithelial sodium channels (αENaC) in endothelial cells in females. Endothelial mineralocorticoid receptors are sex-specifically upregulated in the vasculature of females, a sex difference which is driven by endothelial progesterone receptor activation, and increased activity of these endothelial mineralocorticoid receptors is a crucial mediator of endothelial dysfunction, and potentially hypertension, in obese female experimental models.
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Affiliation(s)
- Jessica L Faulkner
- Vascular Biology Center, Department of Medicine (Cardiology), Medical College of Georgia, Augusta University, 1460 Laney Walker Blvd., Augusta, GA, 30912, USA
| | - Eric J Belin de Chantemèle
- Vascular Biology Center, Department of Medicine (Cardiology), Medical College of Georgia, Augusta University, 1460 Laney Walker Blvd., Augusta, GA, 30912, USA.
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11
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Dugbartey GJ, Quinn B, Luo L, Mickelsen DM, Ture SK, Morrell CN, Czyzyk J, Doyley MM, Yan C, Berk BC, Korshunov VA. The Protective Role of Natriuretic Peptide Receptor 2 against High Salt Injury in the Renal Papilla. THE AMERICAN JOURNAL OF PATHOLOGY 2019; 189:1721-1731. [PMID: 31220449 PMCID: PMC6724224 DOI: 10.1016/j.ajpath.2019.05.020] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/23/2019] [Revised: 05/11/2019] [Accepted: 05/28/2019] [Indexed: 12/20/2022]
Abstract
Mutations in natriuretic peptide receptor 2 (Npr2) gene cause a rare form of short-limbed dwarfism, but its physiological effects have not been well studied. Human and mouse genetic data suggest that Npr2 in the kidney plays a role in salt homeostasis. Herein, we described anatomic changes within renal papilla of Npr2 knockout (Npr2-/-) mice. Dramatic reduction was found in diuresis, and albuminuria was evident after administration of 1% NaCl in drinking water in Npr2-/- and heterozygous (Npr2+/-) mice compared with their wild-type (Npr2+/+) littermates. There was indication of renal epithelial damage accompanied by high numbers of red blood cells and inflammatory cells (macrophage surface glycoproteins binding to galectin-3) and an increase of renal epithelial damage marker (T-cell Ig and mucin domain 1) in Npr2-/- mice. Addition of 1% NaCl tended to increase apoptotic cells (cleaved caspase 3) in the renal papilla of Npr2-/- mice. In vitro, genetic silencing of the Npr2 abolished protective effects of C-type natriuretic peptide, a ligand for Npr2, against death of M-1 kidney epithelial cells exposed to 360 mmol/L NaCl. Finally, significantly lower levels of expression of the NPR2 protein were detected in renal samples of hypertensive compared with normotensive human subjects. Taken together, these findings suggest that Npr2 is essential to protect renal epithelial cells from high concentrations of salt and prevent kidney injury.
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Affiliation(s)
- George J Dugbartey
- Aab Cardiovascular Research Institute, Hajim School of Engineering and Applied Sciences, University of Rochester, Rochester, New York
| | - Breandan Quinn
- Aab Cardiovascular Research Institute, Hajim School of Engineering and Applied Sciences, University of Rochester, Rochester, New York
| | - Lingfeng Luo
- Aab Cardiovascular Research Institute, Hajim School of Engineering and Applied Sciences, University of Rochester, Rochester, New York
| | - Deanne M Mickelsen
- Aab Cardiovascular Research Institute, Hajim School of Engineering and Applied Sciences, University of Rochester, Rochester, New York
| | - Sara K Ture
- Aab Cardiovascular Research Institute, Hajim School of Engineering and Applied Sciences, University of Rochester, Rochester, New York
| | - Craig N Morrell
- Aab Cardiovascular Research Institute, Hajim School of Engineering and Applied Sciences, University of Rochester, Rochester, New York
| | - Jan Czyzyk
- Department of Laboratory Medicine and Pathology, University of Minnesota, Minneapolis, Minnesota
| | - Marvin M Doyley
- Department of Electrical and Computer Engineering, Hajim School of Engineering and Applied Sciences, University of Rochester, Rochester, New York
| | - Chen Yan
- Aab Cardiovascular Research Institute, Hajim School of Engineering and Applied Sciences, University of Rochester, Rochester, New York
| | - Bradford C Berk
- Aab Cardiovascular Research Institute, Hajim School of Engineering and Applied Sciences, University of Rochester, Rochester, New York; Department of Medicine, Neurorestoration Institute, Hajim School of Engineering and Applied Sciences, University of Rochester, Rochester, New York.
| | - Vyacheslav A Korshunov
- Aab Cardiovascular Research Institute, Hajim School of Engineering and Applied Sciences, University of Rochester, Rochester, New York.
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12
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CaSR participates in the regulation of vascular tension in the mesentery of hypertensive rats via the PLC‑IP3/AC‑V/cAMP/RAS pathway. Mol Med Rep 2019; 20:4433-4448. [PMID: 31485595 PMCID: PMC6797953 DOI: 10.3892/mmr.2019.10620] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2019] [Accepted: 07/12/2019] [Indexed: 12/20/2022] Open
Abstract
Hypertension is a cardiovascular disease that severely impairs human health; however, its specific etiology and pathogenesis are complex. The present study investigated the effects of the calcium sensing receptor (CaSR) on vascular tone in spontaneously hypertensive rats (SHRs), and clarified the role and mechanism of CaSR in regulating this property with respect to the phospholipase C (PLC)-inositol 1,4,5-triphosphate (IP3)/adenylate cyclase-V(AC-V)/cyclic adenosine monophosphate (cAMP)/renin-angiotensin system (RAS) pathway in these animals. CaSR protein expression in the mesenteric artery (MA) of rats and CaSR protein expression in SHRs were significantly reduced. Based on wire myography studies, vasoconstriction was significantly augmented and vasodilatation was attenuated in SHRs, and this effect was endothelium-independent. The CaSR calcimimetic NPSR568 and inhibitor NPS2143 reduced vasoconstriction and enhanced vasodilation in SHRs. Furthermore, pretreatment with PLC-IP3/AC-V/cAMP/RAS pathway blockers significantly reduced the vasoconstriction response and enhanced the vasodilator response in SHRs and Wistar-Kyoto rats (WKY), and these effects were partially dependent on the endothelium. Additionally, pretreatment with CaSR inhibitors were determined to cooperate with the PLC-IP3/AC-V/cAMP/RAS pathway inhibitors to significantly reduce vasoconstriction and enhance vasodilation in SHRs and WKY. Our results demonstrated that CaSR is functionally expressed in the MA of SHRs, and that CaSR expression is decreased in SHRs. Additionally, vasoconstriction was enhanced while vasodilatation was attenuated in SHRs; these processes were determined to be endothelium-independent. CaSR is involved in the regulation of blood pressure and vascular tension in SHRs and WKYs. In association with mechanistic differences, this effect was proposed to be partially endothelium-dependent and mediated by the PLC-IP3/AC-V/cAMP/RAS pathway.
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13
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Faulkner JL, Kennard S, Huby AC, Antonova G, Lu Q, Jaffe IZ, Patel VS, Fulton DJR, Belin de Chantemèle EJ. Progesterone Predisposes Females to Obesity-Associated Leptin-Mediated Endothelial Dysfunction via Upregulating Endothelial MR (Mineralocorticoid Receptor) Expression. Hypertension 2019; 74:678-686. [PMID: 31327274 DOI: 10.1161/hypertensionaha.119.12802] [Citation(s) in RCA: 44] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
Compelling clinical evidence indicates that obesity and its associated metabolic abnormalities supersede the protective effects of female sex-hormones and predisposes premenopausal women to cardiovascular disease. The underlying mechanisms remain poorly defined; however, recent studies have implicated overactivation of the aldosterone-MR (mineralocorticoid receptor) axis as a cause of sex-specific cardiovascular risk in obese females. Experimental evidence indicates that the MR on endothelial cells contributes to obesity-associated, leptin-induced endothelial dysfunction in female experimental models, however, the vascular-specific mechanisms via which females are predisposed to heightened endothelial MR activation remain unknown. Therefore, we hypothesized that endogenous expression of endothelial MR is higher in females than males, which predisposes them to obesity-associated, leptin-mediated endothelial dysfunction. We found that endothelial MR expression is higher in blood vessels from female mice and humans compared with those of males, and further, that PrR (progesterone receptor) activation in endothelial cells is the driving mechanism for sex-dependent increases in endothelial MR expression in females. In addition, we show that genetic deletion of either the endothelial MR or PrR in female mice prevents leptin-induced endothelial dysfunction, providing direct evidence that interaction between the PrR and MR mediates obesity-associated endothelial impairment in females. Collectively, these novel findings suggest that progesterone drives sex-differences in endothelial MR expression and predisposes female mice to leptin-induced endothelial dysfunction, which indicates that MR antagonists may be a promising sex-specific therapy to reduce the risk of cardiovascular diseases in obese premenopausal women.
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Affiliation(s)
- Jessica L Faulkner
- From the Vascular Biology Center (J.L.F., S.K., A.-C.H., G.A., D.J.R.F., E.J.B.d.C.), Medical College of Georgia, Augusta University, GA
| | - Simone Kennard
- From the Vascular Biology Center (J.L.F., S.K., A.-C.H., G.A., D.J.R.F., E.J.B.d.C.), Medical College of Georgia, Augusta University, GA
| | - Anne-Cecile Huby
- From the Vascular Biology Center (J.L.F., S.K., A.-C.H., G.A., D.J.R.F., E.J.B.d.C.), Medical College of Georgia, Augusta University, GA
| | - Galina Antonova
- From the Vascular Biology Center (J.L.F., S.K., A.-C.H., G.A., D.J.R.F., E.J.B.d.C.), Medical College of Georgia, Augusta University, GA
| | - Qing Lu
- Molecular Cardiology Research Institute, Tufts Medical Center, Boston, MA (Q.L., I.Z.J.)
| | - Iris Z Jaffe
- Molecular Cardiology Research Institute, Tufts Medical Center, Boston, MA (Q.L., I.Z.J.)
| | - Vijay S Patel
- Department of Surgery, Section of Cardiothoracic Surgery (V.S.P.), Medical College of Georgia, Augusta University, GA
| | - David J R Fulton
- From the Vascular Biology Center (J.L.F., S.K., A.-C.H., G.A., D.J.R.F., E.J.B.d.C.), Medical College of Georgia, Augusta University, GA
| | - Eric J Belin de Chantemèle
- From the Vascular Biology Center (J.L.F., S.K., A.-C.H., G.A., D.J.R.F., E.J.B.d.C.), Medical College of Georgia, Augusta University, GA.,Department of Medicine, Section of Cardiology (E.J.B.d.C.), Medical College of Georgia, Augusta University, GA
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14
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Caniffi C, Cerniello FM, Bouchet G, Sueiro ML, Tomat A, Maglio DG, Toblli JE, Arranz C. Chronic treatment with C-type natriuretic peptide impacts differently in the aorta of normotensive and hypertensive rats. Pflugers Arch 2019; 471:1103-1115. [DOI: 10.1007/s00424-019-02287-y] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2019] [Revised: 05/20/2019] [Accepted: 05/22/2019] [Indexed: 12/24/2022]
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15
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Moyes AJ, Hobbs AJ. C-type Natriuretic Peptide: A Multifaceted Paracrine Regulator in the Heart and Vasculature. Int J Mol Sci 2019; 20:E2281. [PMID: 31072047 PMCID: PMC6539462 DOI: 10.3390/ijms20092281] [Citation(s) in RCA: 80] [Impact Index Per Article: 16.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2019] [Revised: 04/30/2019] [Accepted: 05/02/2019] [Indexed: 12/11/2022] Open
Abstract
C-type natriuretic peptide (CNP) is an autocrine and paracrine mediator released by endothelial cells, cardiomyocytes and fibroblasts that regulates vital physiological functions in the cardiovascular system. These roles are conveyed via two cognate receptors, natriuretic peptide receptor B (NPR-B) and natriuretic peptide receptor C (NPR-C), which activate different signalling pathways that mediate complementary yet distinct cellular responses. Traditionally, CNP has been deemed the endothelial component of the natriuretic peptide system, while its sibling peptides, atrial natriuretic peptide (ANP) and brain natriuretic peptide (BNP), are considered the endocrine guardians of cardiac function and blood volume. However, accumulating evidence indicates that CNP not only modulates vascular tone and blood pressure, but also governs a wide range of cardiovascular effects including the control of inflammation, angiogenesis, smooth muscle and endothelial cell proliferation, atherosclerosis, cardiomyocyte contractility, hypertrophy, fibrosis, and cardiac electrophysiology. This review will focus on the novel physiological functions ascribed to CNP, the receptors/signalling mechanisms involved in mediating its cardioprotective effects, and the development of therapeutics targeting CNP signalling pathways in different disease pathologies.
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Affiliation(s)
- Amie J Moyes
- William Harvey Research Institute, Barts and The London School of Medicine & Dentistry, Queen Mary University of London, Charterhouse Square, London EC1M 6BQ, UK.
| | - Adrian J Hobbs
- William Harvey Research Institute, Barts and The London School of Medicine & Dentistry, Queen Mary University of London, Charterhouse Square, London EC1M 6BQ, UK.
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16
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Li Q, Pang M, Zhu M, Chen L. G-Protein-gated Inwardly-Rectifying K + Channels and Large-conductance Calcium-Activated K + Channels Are Involved in C-Type Natriuretic Peptide-Mediated Vasodilation in Human Arteries. Int Heart J 2018; 60:168-174. [PMID: 30393264 DOI: 10.1536/ihj.18-004] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
C-type natriuretic peptide (CNP) hyperpolarizes and relaxes the smooth muscle of blood vessels. We investigated whether G-protein-gated inwardly-rectifying K+ channels (GIRK) and large-conductance calcium-activated K+ channels (BKCa channels) were involved in CNP-evoked vasodilatation in human arteries. Isometric tension in human gastroepiploic arteries was measured using a wire myograph. Ion channel currents were recorded by the whole-cell patch-clamp technique. The concentration-dependent vasodilation induced by CNP was reduced significantly after inhibition of GIRK channels (by tertiapin-Q) or of BKCa channel (by paxilline). Immunochemical experiments showed that GIRK3 and GIRK4 subunits were expressed in human arteries. CNP also strongly increased the current density of GIRK and BKCa channels in human arterial smooth muscles. This suggested that the GIRK channel was functionally expressed in smooth muscle and vasodilation action was produced by CNP partly by opening the GIRK and BKCa channels in the human artery.
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Affiliation(s)
- Qiyong Li
- Department of Cardiology, Sichuan Academy of Medical Sciences & Sichuan Provincial People's Hospital
| | - Minghui Pang
- Department of Gastrointestinal Surgery, Sichuan Academy of Medical Sciences & Sichuan Provincial People's Hospital
| | - Minjia Zhu
- Department of Physiology, West China School of Basic Medical Sciences & Forensic Medicine, Sichuan University
| | - Li Chen
- Department of Physiology, West China School of Basic Medical Sciences & Forensic Medicine, Sichuan University
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