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Hu XQ, Zhang L. Oxidative Regulation of Vascular Ca v1.2 Channels Triggers Vascular Dysfunction in Hypertension-Related Disorders. Antioxidants (Basel) 2022; 11:antiox11122432. [PMID: 36552639 PMCID: PMC9774363 DOI: 10.3390/antiox11122432] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2022] [Revised: 11/28/2022] [Accepted: 12/06/2022] [Indexed: 12/13/2022] Open
Abstract
Blood pressure is determined by cardiac output and peripheral vascular resistance. The L-type voltage-gated Ca2+ (Cav1.2) channel in small arteries and arterioles plays an essential role in regulating Ca2+ influx, vascular resistance, and blood pressure. Hypertension and preeclampsia are characterized by high blood pressure. In addition, diabetes has a high prevalence of hypertension. The etiology of these disorders remains elusive, involving the complex interplay of environmental and genetic factors. Common to these disorders are oxidative stress and vascular dysfunction. Reactive oxygen species (ROS) derived from NADPH oxidases (NOXs) and mitochondria are primary sources of vascular oxidative stress, whereas dysfunction of the Cav1.2 channel confers increased vascular resistance in hypertension. This review will discuss the importance of ROS derived from NOXs and mitochondria in regulating vascular Cav1.2 and potential roles of ROS-mediated Cav1.2 dysfunction in aberrant vascular function in hypertension, diabetes, and preeclampsia.
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2
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Wilcox CS, Wang C, Wang D. Endothelin-1-Induced Microvascular ROS and Contractility in Angiotensin-II-Infused Mice Depend on COX and TP Receptors. Antioxidants (Basel) 2019; 8:antiox8060193. [PMID: 31234522 PMCID: PMC6616505 DOI: 10.3390/antiox8060193] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2019] [Revised: 06/12/2019] [Accepted: 06/19/2019] [Indexed: 01/16/2023] Open
Abstract
(1) Background: Angiotensin II (Ang II) and endothelin 1 (ET-1) generate reactive oxygen species (ROS) that can activate cyclooxygenase (COX). However, thromboxane prostanoid receptors (TPRs) are required to increase systemic markers of ROS during Ang II infusion in mice. We hypothesized that COX and TPRs are upstream requirements for the generation of vascular ROS by ET-1. (2) Methods: ET-1-induced vascular contractions and ROS were assessed in mesenteric arterioles from wild type (+/+) and knockout (−/−) of COX1 or TPR mice infused with Ang II (400 ng/kg/min × 14 days) or a vehicle. (3) Results: Ang II infusion appeared to increase microvascular protein expression of endothelin type A receptors (ETARs), TPRs, and COX1 and 2 in COX1 and TPR +/+ mice but not in −/− mice. Ang II infusion increased ET-1-induced vascular contractions and ROS, which were prevented by a blockade of COX1 and 2 in TPR −/− mice. ET-1 increased the activity of aortic nicotinamide adenine dinucleotide phosphate (NADPH) oxidase and decreased superoxide dismutase (SOD) 1, 2, and 3 in Ang-II-infused mice, which were prevented by a blockade of TPRs. (4) Conclusion: Activation of vascular TPRs by COX products are required for ET-1 to increase vascular contractions and ROS generation from NADPH oxidase and reduce ROS metabolism by SOD. These effects require an increase in these systems by prior infusion of Ang II.
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Affiliation(s)
- Christopher S Wilcox
- Division of Nephrology and Hypertension, Department of Medicine, Georgetown University, Washington, DC 20007, USA.
| | - Cheng Wang
- Division of Nephrology and Hypertension, Department of Medicine, Georgetown University, Washington, DC 20007, USA.
| | - Dan Wang
- Division of Nephrology and Hypertension, Department of Medicine, Georgetown University, Washington, DC 20007, USA.
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3
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Kopf PG, Phelps LE, Schupbach CD, Johnson AK, Peuler JD. Differential effects of long-term slow-pressor and subpressor angiotensin II on contractile and relaxant reactivity of resistance versus conductance arteries. Physiol Rep 2018; 6:e13623. [PMID: 29504268 PMCID: PMC5835495 DOI: 10.14814/phy2.13623] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2017] [Revised: 01/17/2018] [Accepted: 01/23/2018] [Indexed: 01/09/2023] Open
Abstract
Vascular reactivity was evaluated in three separate arteries isolated from rats after angiotensin II (Ang II) was infused chronically in two separate experiments, one using a 14-day high, slow-pressor dose known to produce hypertension and the other using a 7-day low, subpressor but hypertensive-sensitizing dose. There were three new findings. First, there was no evidence of altered vascular reactivity in resistance arteries that might otherwise explain the hypertension due to the high Ang II or the hypertensive-sensitizing effect of the low Ang II dose. Second, the high Ang II dose exerted a novel differential effect on arterial contractile responsiveness to the sympathetic neurotransmitter, norepinephrine, depending on the level of sympathetic innervation. It clearly enhanced that responsiveness in the sparsely innervated aorta but not in small mesenteric resistance arteries or the proximal (conductance) portion of the caudal artery, both of which are densely innervated. This suggests that the increased expression of alpha adrenergic receptors after long-term exposure to Ang II as previously reported for aortic smooth muscle, is prevented in densely innervated arteries, likely due to long-term Ang II-mediated increase in sympathetic neural traffic to those vessels. Third, the same high dose of Ang II impaired aortic relaxation in response to the nitric oxide (NO) donor nitroprusside without impairing aortic endothelium-dependent relaxation. NO is the main relaxing substance released by aortic endothelium. Accordingly, it is possible that this dose of Ang II is also associated with enhanced release of and/or enhanced smooth muscle responsiveness to other endothelial relaxing substances in a compensatory capacity.
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Affiliation(s)
- Phillip G. Kopf
- Department of PharmacologyMidwestern UniversityDowners GroveIllinois
| | - Laura E. Phelps
- Department of PharmacologyMidwestern UniversityDowners GroveIllinois
| | - Chad D. Schupbach
- Department of PharmacologyMidwestern UniversityDowners GroveIllinois
| | - Alan K. Johnson
- Departments of Psychological and Brain SciencesHealth and Human Physiology, and Pharmacologythe University of IowaIowa CityIowa
| | - Jacob D. Peuler
- Department of PharmacologyMidwestern UniversityDowners GroveIllinois
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4
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Wang C, Luo Z, Carter G, Wellstein A, Jose PA, Tomlinson J, Leiper J, Welch WJ, Wilcox CS, Wang D. NRF2 prevents hypertension, increased ADMA, microvascular oxidative stress, and dysfunction in mice with two weeks of ANG II infusion. Am J Physiol Regul Integr Comp Physiol 2017; 314:R399-R406. [PMID: 29167164 DOI: 10.1152/ajpregu.00122.2017] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
Nuclear factor erythyroid factor 2 (Nrf2) transcribes genes in cultured endothelial cells that reduce reactive oxygen species (ROS) and generate nitric oxide (NO) or metabolize asymmetric dimethylarginine (ADMA), which inhibits NO synthase (NOS). Therefore, we undertook a functional study to test the hypothesis that activation of Nrf2 by tert-butylhydroquinone (tBHQ) preserves microvascular endothelial function during oxidative stress. Wild-type CB57BL/6 (wt), Nrf2 wt (+/+), or knockout (-/-) mice received vehicle (Veh) or tBHQ (0.1%; activator of Nrf2) during 14-day infusions of ANG II (to induce oxidative stress) or sham. MAP was recorded by telemetry. Mesenteric resistance arterioles were studied on isometric myographs and vascular NO and ROS by fluorescence microscopy. ANG II increased the mean arterial pressure (112 ± 5 vs. 145 ± 5 mmHg; P < 0.01) and excretion of 8-isoprostane F2α (2.8 ± 0.3 vs. 3.8 ± 0.3 ng/mg creatinine; P < 0.05) at 12-14 days. However, 12 days of ANG II reduced endothelium-derived relaxation (27 ± 5 vs. 17 ± 3%; P < 0.01) and NO (0.38 ± 0.07 vs. 0.18 ± 0.03 units; P < 0.01) but increased microvascular remodeling, endothelium-derived contractions (7.5 ± 0.5 vs. 13.0 ± 1.7%; P < 0.01), superoxide (0.09 ± 0.03 vs. 0.29 ± 0.08 units; P < 0.05), and contractions to U-46,619 (87 ± 6 vs. 118 ± 3%; P < 0.05), and endothelin-1(89 ± 4 vs. 123 ± 12%; P < 0.05). tBHQ prevented all of these effects of ANG II at 12-14 days in Nrf2+/+ mice but not in Nrf2-/- mice. In conclusion, tBHQ activates Nrf2 to prevent microvascular endothelial dysfunction, remodeling, and contractility, and moderate ADMA and hypertension at 12-14 days of ANG II infusion, thereby preserving endothelial function and preventing hypertension.
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Affiliation(s)
- Cheng Wang
- Hypertension Center and Division of Nephrology and Hypertension, Georgetown University , Washington, D.C.,Division of Nephrology, Department of Medicine, 5th Hospital of Sun Yat-Sen University , Zhuhai, Guangdong , China
| | - Zaiming Luo
- Hypertension Center and Division of Nephrology and Hypertension, Georgetown University , Washington, D.C
| | - Gabriella Carter
- Hypertension Center and Division of Nephrology and Hypertension, Georgetown University , Washington, D.C
| | - Anton Wellstein
- Lombardi Cancer Center, Georgetown University , Washington, D.C
| | - Pedro A Jose
- Division of Nephrology, George Washington University School of Medicine and Health Sciences , Washington, D.C
| | - James Tomlinson
- Institute of Clinical Sciences, Faculty of Medicine, Imperial College , London , United Kingdom
| | - James Leiper
- Institute of Cardiovascular and Medical Sciences , University of Glasgow , Glasgow United Kingdom
| | - William J Welch
- Hypertension Center and Division of Nephrology and Hypertension, Georgetown University , Washington, D.C
| | - Christopher S Wilcox
- Hypertension Center and Division of Nephrology and Hypertension, Georgetown University , Washington, D.C
| | - Dan Wang
- Hypertension Center and Division of Nephrology and Hypertension, Georgetown University , Washington, D.C
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5
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Siedlinski M, Nosalski R, Szczepaniak P, Ludwig-Gałęzowska AH, Mikołajczyk T, Filip M, Osmenda G, Wilk G, Nowak M, Wołkow P, Guzik TJ. Vascular transcriptome profiling identifies Sphingosine kinase 1 as a modulator of angiotensin II-induced vascular dysfunction. Sci Rep 2017; 7:44131. [PMID: 28276483 PMCID: PMC5343497 DOI: 10.1038/srep44131] [Citation(s) in RCA: 30] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2016] [Accepted: 02/03/2017] [Indexed: 12/22/2022] Open
Abstract
Vascular dysfunction is an important phenomenon in hypertension. We hypothesized that angiotensin II (AngII) affects transcriptome in the vasculature in a region-specific manner, which may help to identify genes related to vascular dysfunction in AngII-induced hypertension. Mesenteric artery and aortic transcriptome was profiled using Illumina WG-6v2.0 chip in control and AngII infused (490 ng/kg/min) hypertensive mice. Gene set enrichment and leading edge analyses identified Sphingosine kinase 1 (Sphk1) in the highest number of pathways affected by AngII. Sphk1 mRNA, protein and activity were up-regulated in the hypertensive vasculature. Chronic sphingosine-1-phosphate (S1P) infusion resulted in a development of significantly increased vasoconstriction and endothelial dysfunction. AngII-induced hypertension was blunted in Sphk1-/- mice (systolic BP 167 ± 4.2 vs. 180 ± 3.3 mmHg, p < 0.05), which was associated with decreased aortic and mesenteric vasoconstriction in hypertensive Sphk1-/- mice. Pharmacological inhibition of S1P synthesis reduced vasoconstriction of mesenteric arteries. While Sphk1 is important in mediating vasoconstriction in hypertension, Sphk1-/- mice were characterized by enhanced endothelial dysfunction, suggesting a local protective role of Sphk1 in the endothelium. S1P serum level in humans was correlated with endothelial function (arterial tonometry). Thus, vascular transcriptome analysis shows that S1P pathway is critical in the regulation of vascular function in AngII-induced hypertension, although Sphk1 may have opposing roles in the regulation of vasoconstriction and endothelium-dependent vasorelaxation.
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Affiliation(s)
- Mateusz Siedlinski
- Department of Internal and Agricultural Medicine, Faculty of Medicine, Jagiellonian University Medical College, Kraków, Poland
| | - Ryszard Nosalski
- Department of Internal and Agricultural Medicine, Faculty of Medicine, Jagiellonian University Medical College, Kraków, Poland.,British Heart Foundation Centre for Excellence, Institute of Cardiovascular and Medical Sciences, University of Glasgow, Glasgow, Scotland, UK
| | - Piotr Szczepaniak
- Department of Internal and Agricultural Medicine, Faculty of Medicine, Jagiellonian University Medical College, Kraków, Poland
| | | | - Tomasz Mikołajczyk
- Department of Internal and Agricultural Medicine, Faculty of Medicine, Jagiellonian University Medical College, Kraków, Poland.,British Heart Foundation Centre for Excellence, Institute of Cardiovascular and Medical Sciences, University of Glasgow, Glasgow, Scotland, UK
| | - Magdalena Filip
- Department of Internal and Agricultural Medicine, Faculty of Medicine, Jagiellonian University Medical College, Kraków, Poland
| | - Grzegorz Osmenda
- Department of Internal and Agricultural Medicine, Faculty of Medicine, Jagiellonian University Medical College, Kraków, Poland
| | - Grzegorz Wilk
- Department of Internal and Agricultural Medicine, Faculty of Medicine, Jagiellonian University Medical College, Kraków, Poland
| | - Michał Nowak
- Department of Internal and Agricultural Medicine, Faculty of Medicine, Jagiellonian University Medical College, Kraków, Poland
| | - Paweł Wołkow
- Centre for Medical Genomics-OMICRON, Jagiellonian University Medical College, Kraków, Poland
| | - Tomasz J Guzik
- Department of Internal and Agricultural Medicine, Faculty of Medicine, Jagiellonian University Medical College, Kraków, Poland.,British Heart Foundation Centre for Excellence, Institute of Cardiovascular and Medical Sciences, University of Glasgow, Glasgow, Scotland, UK
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6
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Heo KS, Berk BC, Abe JI. Disturbed Flow-Induced Endothelial Proatherogenic Signaling Via Regulating Post-Translational Modifications and Epigenetic Events. Antioxid Redox Signal 2016; 25:435-50. [PMID: 26714841 PMCID: PMC5076483 DOI: 10.1089/ars.2015.6556] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/27/2015] [Revised: 12/02/2015] [Accepted: 12/23/2015] [Indexed: 12/21/2022]
Abstract
SIGNIFICANCE Hemodynamic shear stress, the frictional force exerted onto the vascular endothelial cell (EC) surface, influences vascular EC functions. Atherosclerotic plaque formation in the endothelium is known to be site specific: disturbed blood flow (d-flow) formed at the lesser curvature of the aortic arch and branch points promotes plaque formation, and steady laminar flow (s-flow) at the greater curvature is atheroprotective. RECENT ADVANCES Post-translational modifications (PTMs), including phosphorylation and SUMOylation, and epigenetic events, including DNA methylation and histone modifications, provide a new perspective on the pathogenesis of atherosclerosis, elucidating how gene expression is altered by d-flow. Activation of PKCζ and p90RSK, SUMOylation of ERK5 and p53, and DNA hypermethylation are uniquely induced by d-flow, but not by s-flow. CRITICAL ISSUES Extensive cross talk has been observed among the phosphorylation, SUMOylation, acetylation, and methylation PTMs, as well as among epigenetic events along the cascade of d-flow-induced signaling, from the top (mechanosensory systems) to the bottom (epigenetic events). In addition, PKCζ activation plays a role in regulating SUMOylation-related enzymes of PIAS4, p90RSK activation plays a role in regulating SUMOylation-related enzymes of Sentrin/SUMO-specific protease (SENP)2, and DNA methyltransferase SUMOylation may play a role in d-flow signaling. FUTURE DIRECTIONS Although possible contributions of DNA events such as histone modification and the epigenetic and cytosolic events of PTMs in d-flow signaling have become clearer, determining the interplay of each PTM and epigenetic event will provide a new paradigm to elucidate the difference between d-flow and s-flow and lead to novel therapeutic interventions to inhibit plaque formation. Antioxid. Redox Signal. 25, 435-450.
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Affiliation(s)
- Kyung-Sun Heo
- Department of Cardiology, Division of Internal Medicine, The University of Texas MD Anderson Cancer Center, Houston, Texas
| | - Bradford C. Berk
- Department of Medicine, Aab Cardiovascular Research Institute, University of Rochester Medical Center, Rochester, New York
| | - Jun-ichi Abe
- Department of Cardiology, Division of Internal Medicine, The University of Texas MD Anderson Cancer Center, Houston, Texas
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7
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Romero M, Jiménez R, Toral M, León-Gómez E, Gómez-Gúzman M, Sánchez M, Zarzuelo MJ, Rodríguez-Gómez I, Rath G, Tamargo J, Pérez-Vizcaíno F, Dessy C, Duarte J. Vascular and Central Activation of Peroxisome Proliferator-Activated Receptor-β Attenuates Angiotensin II-Induced Hypertension: Role of RGS-5. J Pharmacol Exp Ther 2016; 358:151-63. [PMID: 27189971 DOI: 10.1124/jpet.116.233106] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2016] [Accepted: 04/25/2016] [Indexed: 11/22/2022] Open
Abstract
Activation of peroxisome proliferator-activated receptor-β/δ (PPARβ) lowers blood pressure in genetic and mineralocorticoid-induced hypertension. Regulator of G-protein-coupled receptor signaling 5 (RGS5) protein, which interferes in angiotensin II (AngII) signaling, is a target gene to PPARβ The aim of the present study was to examine whether PPARβ activation in resistance arteries and brain tissues prevents the elevated blood pressure in AngII-induced hypertension and evaluate the role of RGS5 in this effect. C57BL/6J male mice were divided into five groups (control mice, PPARβ agonist [4-[[[2-[3-Fluoro-4-(trifluoromethyl)phenyl]-4-methyl-5-thiazolyl]methyl]thio]-2-methylphenoxy]acetic acid (GW0742)-treated mice AngII-infused mice, GW0742-treated AngII-infused mice, and AngII-infused mice treated with GW0742 plus PPARβ antagonist 3-[[[2-Methoxy-4-(phenylamino)phenyl]amino]sulfonyl]-2-thiophenecarboxylic acid methyl ester (GSK0660)) and were followed for 3 weeks. GW0742 prevented the increase in both arterial blood pressure and plasma noradrenaline levels and the higher reduction of blood pressure after ganglionic blockade, whereas it reduced the mesenteric arterial remodeling and the hyper-responsiveness to vasoconstrictors (AngII and endothelin-1) in AngII-infused mice. These effects were accompanied by an inhibition of NADPH oxidase expression and activity in the brain. Gene expression profiling revealed a marked loss of brainstem and vascular RGS5 in AngII-infused mice, which was restored by GW0742. GW0742-induced effects were abolished by GSK0660. Small interfering RNA targeting RGS5 caused augmented contractile response to AngII in resistance mesenteric arteries and blunted the inhibitory effect of GW0742 on this response. In conclusion, GW0742 exerted antihypertensive effects, restoring sympathetic tone and vascular structure and function in AngII-infused mice by PPARβ activation in brain and vessels inhibiting AngII signaling as a result of RGS5 upregulation.
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Affiliation(s)
- Miguel Romero
- Department of Pharmacology, School of Pharmacy (M.R., R.J., M.T., M.G.-G., M.S., M.J.Z., J.D.), and Department of Physiology (I.R.-G.); University of Granada, Granada, Spain; Center for Biomedical Research, Granada, Spain (R.J., J.D.); Pole of Pharmacology and Therapeutics, Institute of Experimental and Clinical Research, School of Medicine, University of Louvain, Brussels, Belgium (E.L.-G., G.R., C.D.); Department of Pharmacology, School of Medicine, University Complutense of Madrid, Madrid, Spain (J.T., F.P.-V.); and Ciber Enfermedades Respiratorias (Ciberes) and Instituto de Investigación Sanitaria Gregorio Marañón (IISGM), Madrid, Spain (F.P.-V.)
| | - Rosario Jiménez
- Department of Pharmacology, School of Pharmacy (M.R., R.J., M.T., M.G.-G., M.S., M.J.Z., J.D.), and Department of Physiology (I.R.-G.); University of Granada, Granada, Spain; Center for Biomedical Research, Granada, Spain (R.J., J.D.); Pole of Pharmacology and Therapeutics, Institute of Experimental and Clinical Research, School of Medicine, University of Louvain, Brussels, Belgium (E.L.-G., G.R., C.D.); Department of Pharmacology, School of Medicine, University Complutense of Madrid, Madrid, Spain (J.T., F.P.-V.); and Ciber Enfermedades Respiratorias (Ciberes) and Instituto de Investigación Sanitaria Gregorio Marañón (IISGM), Madrid, Spain (F.P.-V.)
| | - Marta Toral
- Department of Pharmacology, School of Pharmacy (M.R., R.J., M.T., M.G.-G., M.S., M.J.Z., J.D.), and Department of Physiology (I.R.-G.); University of Granada, Granada, Spain; Center for Biomedical Research, Granada, Spain (R.J., J.D.); Pole of Pharmacology and Therapeutics, Institute of Experimental and Clinical Research, School of Medicine, University of Louvain, Brussels, Belgium (E.L.-G., G.R., C.D.); Department of Pharmacology, School of Medicine, University Complutense of Madrid, Madrid, Spain (J.T., F.P.-V.); and Ciber Enfermedades Respiratorias (Ciberes) and Instituto de Investigación Sanitaria Gregorio Marañón (IISGM), Madrid, Spain (F.P.-V.)
| | - Elvira León-Gómez
- Department of Pharmacology, School of Pharmacy (M.R., R.J., M.T., M.G.-G., M.S., M.J.Z., J.D.), and Department of Physiology (I.R.-G.); University of Granada, Granada, Spain; Center for Biomedical Research, Granada, Spain (R.J., J.D.); Pole of Pharmacology and Therapeutics, Institute of Experimental and Clinical Research, School of Medicine, University of Louvain, Brussels, Belgium (E.L.-G., G.R., C.D.); Department of Pharmacology, School of Medicine, University Complutense of Madrid, Madrid, Spain (J.T., F.P.-V.); and Ciber Enfermedades Respiratorias (Ciberes) and Instituto de Investigación Sanitaria Gregorio Marañón (IISGM), Madrid, Spain (F.P.-V.)
| | - Manuel Gómez-Gúzman
- Department of Pharmacology, School of Pharmacy (M.R., R.J., M.T., M.G.-G., M.S., M.J.Z., J.D.), and Department of Physiology (I.R.-G.); University of Granada, Granada, Spain; Center for Biomedical Research, Granada, Spain (R.J., J.D.); Pole of Pharmacology and Therapeutics, Institute of Experimental and Clinical Research, School of Medicine, University of Louvain, Brussels, Belgium (E.L.-G., G.R., C.D.); Department of Pharmacology, School of Medicine, University Complutense of Madrid, Madrid, Spain (J.T., F.P.-V.); and Ciber Enfermedades Respiratorias (Ciberes) and Instituto de Investigación Sanitaria Gregorio Marañón (IISGM), Madrid, Spain (F.P.-V.)
| | - Manuel Sánchez
- Department of Pharmacology, School of Pharmacy (M.R., R.J., M.T., M.G.-G., M.S., M.J.Z., J.D.), and Department of Physiology (I.R.-G.); University of Granada, Granada, Spain; Center for Biomedical Research, Granada, Spain (R.J., J.D.); Pole of Pharmacology and Therapeutics, Institute of Experimental and Clinical Research, School of Medicine, University of Louvain, Brussels, Belgium (E.L.-G., G.R., C.D.); Department of Pharmacology, School of Medicine, University Complutense of Madrid, Madrid, Spain (J.T., F.P.-V.); and Ciber Enfermedades Respiratorias (Ciberes) and Instituto de Investigación Sanitaria Gregorio Marañón (IISGM), Madrid, Spain (F.P.-V.)
| | - María José Zarzuelo
- Department of Pharmacology, School of Pharmacy (M.R., R.J., M.T., M.G.-G., M.S., M.J.Z., J.D.), and Department of Physiology (I.R.-G.); University of Granada, Granada, Spain; Center for Biomedical Research, Granada, Spain (R.J., J.D.); Pole of Pharmacology and Therapeutics, Institute of Experimental and Clinical Research, School of Medicine, University of Louvain, Brussels, Belgium (E.L.-G., G.R., C.D.); Department of Pharmacology, School of Medicine, University Complutense of Madrid, Madrid, Spain (J.T., F.P.-V.); and Ciber Enfermedades Respiratorias (Ciberes) and Instituto de Investigación Sanitaria Gregorio Marañón (IISGM), Madrid, Spain (F.P.-V.)
| | - Isabel Rodríguez-Gómez
- Department of Pharmacology, School of Pharmacy (M.R., R.J., M.T., M.G.-G., M.S., M.J.Z., J.D.), and Department of Physiology (I.R.-G.); University of Granada, Granada, Spain; Center for Biomedical Research, Granada, Spain (R.J., J.D.); Pole of Pharmacology and Therapeutics, Institute of Experimental and Clinical Research, School of Medicine, University of Louvain, Brussels, Belgium (E.L.-G., G.R., C.D.); Department of Pharmacology, School of Medicine, University Complutense of Madrid, Madrid, Spain (J.T., F.P.-V.); and Ciber Enfermedades Respiratorias (Ciberes) and Instituto de Investigación Sanitaria Gregorio Marañón (IISGM), Madrid, Spain (F.P.-V.)
| | - Geraldine Rath
- Department of Pharmacology, School of Pharmacy (M.R., R.J., M.T., M.G.-G., M.S., M.J.Z., J.D.), and Department of Physiology (I.R.-G.); University of Granada, Granada, Spain; Center for Biomedical Research, Granada, Spain (R.J., J.D.); Pole of Pharmacology and Therapeutics, Institute of Experimental and Clinical Research, School of Medicine, University of Louvain, Brussels, Belgium (E.L.-G., G.R., C.D.); Department of Pharmacology, School of Medicine, University Complutense of Madrid, Madrid, Spain (J.T., F.P.-V.); and Ciber Enfermedades Respiratorias (Ciberes) and Instituto de Investigación Sanitaria Gregorio Marañón (IISGM), Madrid, Spain (F.P.-V.)
| | - Juan Tamargo
- Department of Pharmacology, School of Pharmacy (M.R., R.J., M.T., M.G.-G., M.S., M.J.Z., J.D.), and Department of Physiology (I.R.-G.); University of Granada, Granada, Spain; Center for Biomedical Research, Granada, Spain (R.J., J.D.); Pole of Pharmacology and Therapeutics, Institute of Experimental and Clinical Research, School of Medicine, University of Louvain, Brussels, Belgium (E.L.-G., G.R., C.D.); Department of Pharmacology, School of Medicine, University Complutense of Madrid, Madrid, Spain (J.T., F.P.-V.); and Ciber Enfermedades Respiratorias (Ciberes) and Instituto de Investigación Sanitaria Gregorio Marañón (IISGM), Madrid, Spain (F.P.-V.)
| | - Francisco Pérez-Vizcaíno
- Department of Pharmacology, School of Pharmacy (M.R., R.J., M.T., M.G.-G., M.S., M.J.Z., J.D.), and Department of Physiology (I.R.-G.); University of Granada, Granada, Spain; Center for Biomedical Research, Granada, Spain (R.J., J.D.); Pole of Pharmacology and Therapeutics, Institute of Experimental and Clinical Research, School of Medicine, University of Louvain, Brussels, Belgium (E.L.-G., G.R., C.D.); Department of Pharmacology, School of Medicine, University Complutense of Madrid, Madrid, Spain (J.T., F.P.-V.); and Ciber Enfermedades Respiratorias (Ciberes) and Instituto de Investigación Sanitaria Gregorio Marañón (IISGM), Madrid, Spain (F.P.-V.)
| | - Chantal Dessy
- Department of Pharmacology, School of Pharmacy (M.R., R.J., M.T., M.G.-G., M.S., M.J.Z., J.D.), and Department of Physiology (I.R.-G.); University of Granada, Granada, Spain; Center for Biomedical Research, Granada, Spain (R.J., J.D.); Pole of Pharmacology and Therapeutics, Institute of Experimental and Clinical Research, School of Medicine, University of Louvain, Brussels, Belgium (E.L.-G., G.R., C.D.); Department of Pharmacology, School of Medicine, University Complutense of Madrid, Madrid, Spain (J.T., F.P.-V.); and Ciber Enfermedades Respiratorias (Ciberes) and Instituto de Investigación Sanitaria Gregorio Marañón (IISGM), Madrid, Spain (F.P.-V.)
| | - Juan Duarte
- Department of Pharmacology, School of Pharmacy (M.R., R.J., M.T., M.G.-G., M.S., M.J.Z., J.D.), and Department of Physiology (I.R.-G.); University of Granada, Granada, Spain; Center for Biomedical Research, Granada, Spain (R.J., J.D.); Pole of Pharmacology and Therapeutics, Institute of Experimental and Clinical Research, School of Medicine, University of Louvain, Brussels, Belgium (E.L.-G., G.R., C.D.); Department of Pharmacology, School of Medicine, University Complutense of Madrid, Madrid, Spain (J.T., F.P.-V.); and Ciber Enfermedades Respiratorias (Ciberes) and Instituto de Investigación Sanitaria Gregorio Marañón (IISGM), Madrid, Spain (F.P.-V.)
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8
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Epigenetic Modifications in Essential Hypertension. Int J Mol Sci 2016; 17:451. [PMID: 27023534 PMCID: PMC4848907 DOI: 10.3390/ijms17040451] [Citation(s) in RCA: 69] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2016] [Revised: 03/15/2016] [Accepted: 03/21/2016] [Indexed: 12/17/2022] Open
Abstract
Essential hypertension (EH) is a complex, polygenic condition with no single causative agent. Despite advances in our understanding of the pathophysiology of EH, hypertension remains one of the world’s leading public health problems. Furthermore, there is increasing evidence that epigenetic modifications are as important as genetic predisposition in the development of EH. Indeed, a complex and interactive genetic and environmental system exists to determine an individual’s risk of EH. Epigenetics refers to all heritable changes to the regulation of gene expression as well as chromatin remodelling, without involvement of nucleotide sequence changes. Epigenetic modification is recognized as an essential process in biology, but is now being investigated for its role in the development of specific pathologic conditions, including EH. Epigenetic research will provide insights into the pathogenesis of blood pressure regulation that cannot be explained by classic Mendelian inheritance. This review concentrates on epigenetic modifications to DNA structure, including the influence of non-coding RNAs on hypertension development.
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9
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Fransen P, Van Hove CE, Leloup AJA, Schrijvers DM, De Meyer GRY, De Keulenaer GW. Effect of angiotensin II-induced arterial hypertension on the voltage-dependent contractions of mouse arteries. Pflugers Arch 2015; 468:257-67. [PMID: 26432297 DOI: 10.1007/s00424-015-1737-x] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2015] [Accepted: 09/22/2015] [Indexed: 11/28/2022]
Abstract
Arterial hypertension (AHT) affects the voltage dependency of L-type Ca(2+) channels in cardiomyocytes. We analyzed the effect of angiotensin II (AngII)-induced AHT on L-type Ca(2+) channel-mediated isometric contractions in conduit arteries. AHT was induced in C57Bl6 mice with AngII-filled osmotic mini-pumps (4 weeks). Normotensive mice treated with saline-filled osmotic mini-pumps were used for comparison. Voltage-dependent contractions mediated by L-type Ca(2+) channels were studied in vaso-reactive studies in vitro in isolated aortic and femoral arteries by using extracellular K(+) concentration-response (KDR) experiments. In aortic segments, AngII-induced AHT significantly sensitized isometric contractions induced by elevated extracellular K(+) and depolarization. This sensitization was partly prevented by normalizing blood pressure with hydralazine, suggesting that it was caused by AHT rather than by direct AngII effects on aortic smooth muscle cells. The EC50 for extracellular K(+) obtained in vitro correlated significantly with the rise in arterial blood pressure induced by AngII in vivo. The AHT-induced sensitization persisted when aortic segments were exposed to levcromakalim or to inhibitors of basal nitric oxide release. Consistent with these observations, AngII-treatment also sensitized the vaso-relaxing effects of the L-type Ca(2+) channel blocker diltiazem during K(+)-induced contractions. Unlike aorta, AngII-treatment desensitized the isometric contractions to depolarization in femoral arteries pointing to vascular bed specific responses of arteries to hypertension. AHT affects the voltage-dependent L-type Ca(2+) channel-mediated contraction of conduit arteries. This effect may contribute to the decreased vascular compliance in AHT and explain the efficacy of Ca(2+) channel blockers to reduce vascular stiffness and central blood pressure in AHT.
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Affiliation(s)
- Paul Fransen
- Department of Pharmaceutical Sciences, Physiopharmacology, Campus Drie Eiken, University of Antwerp, T2, Universiteitsplein 1, 2610, Antwerp, Belgium.
| | - Cor E Van Hove
- Faculty of Medicine & Health Sciences, Pharmacology, Campus Drie Eiken, University of Antwerp, T2, Universiteitsplein 1, 2610, Antwerp, Belgium
| | - Arthur J A Leloup
- Department of Pharmaceutical Sciences, Physiopharmacology, Campus Drie Eiken, University of Antwerp, T2, Universiteitsplein 1, 2610, Antwerp, Belgium
| | - Dorien M Schrijvers
- Department of Pharmaceutical Sciences, Physiopharmacology, Campus Drie Eiken, University of Antwerp, T2, Universiteitsplein 1, 2610, Antwerp, Belgium
| | - Guido R Y De Meyer
- Department of Pharmaceutical Sciences, Physiopharmacology, Campus Drie Eiken, University of Antwerp, T2, Universiteitsplein 1, 2610, Antwerp, Belgium
| | - Gilles W De Keulenaer
- Department of Pharmaceutical Sciences, Physiopharmacology, Campus Drie Eiken, University of Antwerp, T2, Universiteitsplein 1, 2610, Antwerp, Belgium
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10
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Wang C, Luo Z, Kohan D, Wellstein A, Jose PA, Welch WJ, Wilcox CS, Wang D. Thromboxane prostanoid receptors enhance contractions, endothelin-1, and oxidative stress in microvessels from mice with chronic kidney disease. Hypertension 2015; 65:1055-63. [PMID: 25733239 DOI: 10.1161/hypertensionaha.115.05244] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2015] [Accepted: 02/10/2015] [Indexed: 02/06/2023]
Abstract
Cardiovascular disease is frequent in chronic kidney disease and has been related to angiotensin II, endothelin-1 (ET-1), thromboxane A2, and reactive oxygen species (ROS). Because activation of thromboxane prostanoid receptors (TP-Rs) can generate ROS, which can generate ET-1, we tested the hypothesis that chronic kidney disease induces cyclooxygenase-2 whose products activate TP-Rs to enhance ET-1 and ROS generation and contractions. Mesenteric resistance arterioles were isolated from C57/BL6 or TP-R+/+ and TP-R-/- mice 3 months after SHAM-operation (SHAM) or surgical reduced renal mass (RRM, n=6/group). Microvascular contractions were studied on a wire myograph. Cellular (ethidium: dihydroethidium) and mitochondrial (mitoSOX) ROS were measured by fluorescence microscopy. Mice with RRM had increased excretion of markers of oxidative stress, thromboxane, and microalbumin; increased plasma ET-1; and increased microvascular expression of p22(phox), cyclooxygenase-2, TP-Rs, preproendothelin and endothelin-A receptors, and increased arteriolar remodeling. They had increased contractions to U-46,619 (118 ± 3 versus 87 ± 6, P<0.05) and ET-1 (108 ± 5 versus 89 ± 4, P<0.05), which were dependent on cellular and mitochondrial ROS, cyclooxygenase-2, and TP-Rs. RRM doubled the ET-1-induced cellular and mitochondrial ROS generation (P<0.05). TP-R-/- mice with RRM lacked these abnormal structural and functional microvascular responses and lacked the increased systemic and the increased microvascular oxidative stress and circulating ET-1. In conclusion, RRM leads to microvascular remodeling and enhanced ET-1-induced cellular and mitochondrial ROS and contractions that are mediated by cyclooxygenase-2 products activating TP-Rs. Thus, TP-Rs can be upstream from enhanced ROS, ET-1, microvascular remodeling, and contractility and may thereby coordinate vascular dysfunction in chronic kidney disease.
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Affiliation(s)
- Cheng Wang
- From the Hypertension, Kidney and Vascular Research Center and Division of Nephrology and Hypertension, Department of Medicine (C.W., Z.L., W.J.W., C.S.W., D.W.) and Department of Oncology, Lombardi Cancer Center (A.W.), Georgetown University, Washington, DC; Department of Nephrology, The Third Hospital of Sun Yat-sen University, Guangzhou, People's Republic of China (C.W.); Division of Nephrology, Department of Medicine, University of Utah, Salt Lake City (D.K.); and Division of Nephrology, Department of Medicine and Department of Physiology, University of Maryland, Baltimore, MD (P.A.J.)
| | - Zaiming Luo
- From the Hypertension, Kidney and Vascular Research Center and Division of Nephrology and Hypertension, Department of Medicine (C.W., Z.L., W.J.W., C.S.W., D.W.) and Department of Oncology, Lombardi Cancer Center (A.W.), Georgetown University, Washington, DC; Department of Nephrology, The Third Hospital of Sun Yat-sen University, Guangzhou, People's Republic of China (C.W.); Division of Nephrology, Department of Medicine, University of Utah, Salt Lake City (D.K.); and Division of Nephrology, Department of Medicine and Department of Physiology, University of Maryland, Baltimore, MD (P.A.J.)
| | - Donald Kohan
- From the Hypertension, Kidney and Vascular Research Center and Division of Nephrology and Hypertension, Department of Medicine (C.W., Z.L., W.J.W., C.S.W., D.W.) and Department of Oncology, Lombardi Cancer Center (A.W.), Georgetown University, Washington, DC; Department of Nephrology, The Third Hospital of Sun Yat-sen University, Guangzhou, People's Republic of China (C.W.); Division of Nephrology, Department of Medicine, University of Utah, Salt Lake City (D.K.); and Division of Nephrology, Department of Medicine and Department of Physiology, University of Maryland, Baltimore, MD (P.A.J.)
| | - Anton Wellstein
- From the Hypertension, Kidney and Vascular Research Center and Division of Nephrology and Hypertension, Department of Medicine (C.W., Z.L., W.J.W., C.S.W., D.W.) and Department of Oncology, Lombardi Cancer Center (A.W.), Georgetown University, Washington, DC; Department of Nephrology, The Third Hospital of Sun Yat-sen University, Guangzhou, People's Republic of China (C.W.); Division of Nephrology, Department of Medicine, University of Utah, Salt Lake City (D.K.); and Division of Nephrology, Department of Medicine and Department of Physiology, University of Maryland, Baltimore, MD (P.A.J.)
| | - Pedro A Jose
- From the Hypertension, Kidney and Vascular Research Center and Division of Nephrology and Hypertension, Department of Medicine (C.W., Z.L., W.J.W., C.S.W., D.W.) and Department of Oncology, Lombardi Cancer Center (A.W.), Georgetown University, Washington, DC; Department of Nephrology, The Third Hospital of Sun Yat-sen University, Guangzhou, People's Republic of China (C.W.); Division of Nephrology, Department of Medicine, University of Utah, Salt Lake City (D.K.); and Division of Nephrology, Department of Medicine and Department of Physiology, University of Maryland, Baltimore, MD (P.A.J.)
| | - William J Welch
- From the Hypertension, Kidney and Vascular Research Center and Division of Nephrology and Hypertension, Department of Medicine (C.W., Z.L., W.J.W., C.S.W., D.W.) and Department of Oncology, Lombardi Cancer Center (A.W.), Georgetown University, Washington, DC; Department of Nephrology, The Third Hospital of Sun Yat-sen University, Guangzhou, People's Republic of China (C.W.); Division of Nephrology, Department of Medicine, University of Utah, Salt Lake City (D.K.); and Division of Nephrology, Department of Medicine and Department of Physiology, University of Maryland, Baltimore, MD (P.A.J.)
| | - Christopher S Wilcox
- From the Hypertension, Kidney and Vascular Research Center and Division of Nephrology and Hypertension, Department of Medicine (C.W., Z.L., W.J.W., C.S.W., D.W.) and Department of Oncology, Lombardi Cancer Center (A.W.), Georgetown University, Washington, DC; Department of Nephrology, The Third Hospital of Sun Yat-sen University, Guangzhou, People's Republic of China (C.W.); Division of Nephrology, Department of Medicine, University of Utah, Salt Lake City (D.K.); and Division of Nephrology, Department of Medicine and Department of Physiology, University of Maryland, Baltimore, MD (P.A.J.)
| | - Dan Wang
- From the Hypertension, Kidney and Vascular Research Center and Division of Nephrology and Hypertension, Department of Medicine (C.W., Z.L., W.J.W., C.S.W., D.W.) and Department of Oncology, Lombardi Cancer Center (A.W.), Georgetown University, Washington, DC; Department of Nephrology, The Third Hospital of Sun Yat-sen University, Guangzhou, People's Republic of China (C.W.); Division of Nephrology, Department of Medicine, University of Utah, Salt Lake City (D.K.); and Division of Nephrology, Department of Medicine and Department of Physiology, University of Maryland, Baltimore, MD (P.A.J.).
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11
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Gomolak JR, Didion SP. Angiotensin II-induced endothelial dysfunction is temporally linked with increases in interleukin-6 and vascular macrophage accumulation. Front Physiol 2014; 5:396. [PMID: 25400581 PMCID: PMC4212611 DOI: 10.3389/fphys.2014.00396] [Citation(s) in RCA: 58] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2014] [Accepted: 09/24/2014] [Indexed: 01/18/2023] Open
Abstract
Angiotensin II (Ang II) is associated with vascular hypertrophy, endothelial dysfunction and activation of a number of inflammatory molecules, however the linear events involved in the development of hypertension and endothelial dysfunction produced in response to Ang II are not well defined. The goal of this study was to examine the dose- and temporal-dependent development of endothelial dysfunction in response to Ang II. Blood pressure and responses of carotid arteries were examined in control (C57Bl/6) mice and in mice infused with 50, 100, 200, 400, or 1000 ng/kg/min Ang II for either 14 or 28 Days. Infusion of Ang II was associated with graded and marked increases in systolic blood pressure and plasma Ang II concentrations. While low doses of Ang II (i.e., 50 and 100 ng/kg/min) had little to no effect on blood pressure or endothelial function, high doses of Ang II (e.g., 1000 ng/kg/min) were associated with large increases in arterial pressure and marked impairment of endothelial function. In contrast, intermediate doses of Ang II (200 and 400 ng/kg/min) while initially having no effect on systolic blood pressure were associated with significant increases in pressure over time. Despite increasing blood pressure, 200 ng/kg/min had no effect on endothelial function, whereas 400 ng/kg/min produced modest impairment on Day 14 and marked impairment of endothelial function on Day 28. The degree of endothelial dysfunction produced by 400 and 1000 ng/kg/min Ang II was reflective of parallel increases in plasma IL-6 levels and vascular macrophage content, suggesting that increases in arterial blood pressure precede the development of endothelial dysfunction. These findings are important as they demonstrate that along with increases in arterial pressure that increases in IL-6 and vascular macrophage accumulation correlate with the impairment of endothelial function produced by Ang II.
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Affiliation(s)
- Jessica R Gomolak
- Department of Pharmacology, The University of Mississippi Medical Center Jackson, MS, USA
| | - Sean P Didion
- Department of Pharmacology, The University of Mississippi Medical Center Jackson, MS, USA ; Department of Neurology, The University of Mississippi Medical Center Jackson, MS, USA
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12
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Kang KT. Endothelium-derived Relaxing Factors of Small Resistance Arteries in Hypertension. Toxicol Res 2014; 30:141-8. [PMID: 25343007 PMCID: PMC4206740 DOI: 10.5487/tr.2014.30.3.141] [Citation(s) in RCA: 81] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2014] [Revised: 08/27/2014] [Accepted: 09/15/2014] [Indexed: 12/13/2022] Open
Abstract
Endothelium-derived relaxing factors (EDRFs), including nitric oxide (NO), prostacyclin (PGI2), and endothelium-derived hyperpolarizing factor (EDHF), play pivotal roles in regulating vascular tone. Reduced EDRFs cause impaired endothelium-dependent vasorelaxation, or endothelial dysfunction. Impaired endothelium-dependent vasorelaxation in response to acetylcholine (ACh) is consistently observed in conduit vessels in human patients and experimental animal models of hypertension. Because small resistance arteries are known to produce more than one type of EDRF, the mechanism(s) mediating endothelium-dependent vasorelaxation in small resistance arteries may be different from that observed in conduit vessels under hypertensive conditions, where vasorelaxation is mainly dependent on NO. EDHF has been described as one of the principal mediators of endothelium-dependent vasorelaxation in small resistance arteries in normotensive animals. Furthermore, EDHF appears to become the predominant endothelium-dependent vasorelaxation pathway when the endothelial NO synthase (NOS3)/NO pathway is absent, as in NOS3-knockout mice, whereas some studies have shown that the EDHF pathway is dysfunctional in experimental models of hypertension. This article reviews our current knowledge regarding EDRFs in small arteries under normotensive and hypertensive conditions.
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Affiliation(s)
- Kyu-Tae Kang
- College of Pharmacy, Duksung Women's University, Seoul, Korea ; Innovative Drug Center, Duksung Women's University, Seoul, Korea
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13
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Dias AT, Cintra AS, Frossard JC, Palomino Z, Casarini DE, Gomes IBS, Balarini CM, Gava AL, Campagnaro BP, Pereira TMC, Meyrelles SS, Vasquez EC. Inhibition of phosphodiesterase 5 restores endothelial function in renovascular hypertension. J Transl Med 2014; 12:250. [PMID: 25223948 PMCID: PMC4172908 DOI: 10.1186/s12967-014-0250-x] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2014] [Accepted: 08/30/2014] [Indexed: 01/25/2023] Open
Abstract
Background The clipping of an artery supplying one of the two kidneys (2K1C) activates the renin-angiotensin (Ang) system (RAS), resulting in hypertension and endothelial dysfunction. Recently, we demonstrated the intrarenal beneficial effects of sildenafil on the high levels of Ang II and reactive oxygen species (ROS) and on high blood pressure (BP) in 2K1C mice. Thus, in the present study, we tested the hypothesis that sildenafil improves endothelial function in hypertensive 2K1C mice by improving the NO/ROS balance. Methods 2K1C hypertension was induced in C57BL/6 mice. Two weeks later, they were treated with sildenafil (40 mg/kg/day, via oral) or vehicle for 2 weeks and compared with sham mice. At the end of the treatment, the levels of plasma and intrarenal Ang peptides were measured. Endothelial function and ROS production were assessed in mesenteric arterial bed (MAB). Results The 2K1C mice exhibited normal plasma levels of Ang I, II and 1–7, whereas the intrarenal Ang I and II were increased (~35% and ~140%) compared with the Sham mice. Sildenafil normalized the intrarenal Ang I and II and increased the plasma (~45%) and intrarenal (+15%) Ang 1–7. The 2K1C mice exhibited endothelial dysfunction, primarily due to increased ROS and decreased NO productions by endothelial cells, which were ameliorated by treatment with sildenafil. Conclusion These data suggest that the effects of sildenafil on endothelial dysfunction in 2K1C mice may be due to interaction with RAS and restoring NO/ROS balance in the endothelial cells from MAB. Thus, sildenafil is a promising candidate drug for the treatment of hypertension accompanied by endothelial dysfunction and kidney disease.
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14
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Sutliff RL, Walp ER, Kim YH, Walker LA, El-Ali AM, Ma J, Bonsall R, Ramosevac S, Eaton DC, Verlander JW, Hansen L, Gleason RLJ, Pham TD, Hong S, Pech V, Wall SM. Contractile force is enhanced in Aortas from pendrin null mice due to stimulation of angiotensin II-dependent signaling. PLoS One 2014; 9:e105101. [PMID: 25148130 PMCID: PMC4141771 DOI: 10.1371/journal.pone.0105101] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2013] [Accepted: 07/20/2014] [Indexed: 11/19/2022] Open
Abstract
Pendrin is a Cl−/HCO3− exchanger expressed in the apical regions of renal intercalated cells. Following pendrin gene ablation, blood pressure falls, in part, from reduced renal NaCl absorption. We asked if pendrin is expressed in vascular tissue and if the lower blood pressure observed in pendrin null mice is accompanied by reduced vascular reactivity. Thus, the contractile responses to KCl and phenylephrine (PE) were examined in isometrically mounted thoracic aortas from wild-type and pendrin null mice. Although pendrin expression was not detected in the aorta, pendrin gene ablation changed contractile protein abundance and increased the maximal contractile response to PE when normalized to cross sectional area (CSA). However, the contractile sensitivity to this agent was unchanged. The increase in contractile force/cross sectional area observed in pendrin null mice was due to reduced cross sectional area of the aorta and not from increased contractile force per vessel. The pendrin-dependent increase in maximal contractile response was endothelium- and nitric oxide-independent and did not occur from changes in Ca2+ sensitivity or chronic changes in catecholamine production. However, application of 100 nM angiotensin II increased force/CSA more in aortas from pendrin null than from wild type mice. Moreover, angiotensin type 1 receptor inhibitor (candesartan) treatment in vivo eliminated the pendrin-dependent changes contractile protein abundance and changes in the contractile force/cross sectional area in response to PE. In conclusion, pendrin gene ablation increases aorta contractile force per cross sectional area in response to angiotensin II and PE due to stimulation of angiotensin type 1 receptor-dependent signaling. The angiotensin type 1 receptor-dependent increase in vascular reactivity may mitigate the fall in blood pressure observed with pendrin gene ablation.
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MESH Headings
- Angiotensin II/pharmacology
- Animals
- Anion Transport Proteins/deficiency
- Anion Transport Proteins/genetics
- Aorta/drug effects
- Aorta/metabolism
- Aorta/pathology
- Calcium/metabolism
- Catecholamines/biosynthesis
- Dose-Response Relationship, Drug
- Gene Expression
- Kidney/metabolism
- Male
- Mice
- Mice, Knockout
- Muscle, Smooth, Vascular/drug effects
- Muscle, Smooth, Vascular/metabolism
- Nitric Oxide/metabolism
- Phenylephrine/pharmacology
- Potassium Chloride/pharmacology
- RNA, Messenger/genetics
- RNA, Messenger/metabolism
- Receptor, Angiotensin, Type 1/metabolism
- Signal Transduction/drug effects
- Sulfate Transporters
- Vasoconstriction/drug effects
- Vasoconstriction/genetics
- Vasoconstrictor Agents/pharmacology
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Affiliation(s)
- Roy L. Sutliff
- Atlanta Veterans Affairs Medical Center, Atlanta, Georgia, United States of America
- Department of Medicine, Emory University, Atlanta, Georgia, United States of America
| | - Erik R. Walp
- Atlanta Veterans Affairs Medical Center, Atlanta, Georgia, United States of America
- Department of Medicine, Emory University, Atlanta, Georgia, United States of America
| | - Young Hee Kim
- Department of Medicine, Emory University, Atlanta, Georgia, United States of America
| | - Lori A. Walker
- Departments of Medicine and Cardiology, University of Colorado Health Sciences Center, Aurora, Colorado, United States of America
| | - Alexander M. El-Ali
- Atlanta Veterans Affairs Medical Center, Atlanta, Georgia, United States of America
- Department of Medicine, Emory University, Atlanta, Georgia, United States of America
| | - Jing Ma
- Atlanta Veterans Affairs Medical Center, Atlanta, Georgia, United States of America
- Department of Medicine, Emory University, Atlanta, Georgia, United States of America
| | - Robert Bonsall
- Department of Psychiatry and Behavioral Sciences, Emory University, Atlanta, Georgia, United States of America
| | - Semra Ramosevac
- Department of Physiology, Emory University, Atlanta, Georgia, United States of America
| | - Douglas C. Eaton
- Department of Physiology, Emory University, Atlanta, Georgia, United States of America
| | - Jill W. Verlander
- Department of Medicine, University of Florida, Gainesville, Florida, United States of America
| | - Laura Hansen
- School of Mechanical Engineering, Georgia Institute of Technology, Atlanta, Georgia, United States of America
| | - Rudolph L. Jr. Gleason
- School of Mechanical Engineering, Georgia Institute of Technology, Atlanta, Georgia, United States of America
| | - Truyen D. Pham
- Department of Medicine, Emory University, Atlanta, Georgia, United States of America
| | - Seongun Hong
- Department of Medicine, Emory University, Atlanta, Georgia, United States of America
| | - Vladimir Pech
- Department of Medicine, Emory University, Atlanta, Georgia, United States of America
| | - Susan M. Wall
- Department of Medicine, Emory University, Atlanta, Georgia, United States of America
- Department of Physiology, Emory University, Atlanta, Georgia, United States of America
- * E-mail:
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15
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Epigenetics, the missing link in hypertension. Life Sci 2014; 129:22-6. [PMID: 25128856 DOI: 10.1016/j.lfs.2014.08.003] [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: 05/05/2014] [Revised: 07/15/2014] [Accepted: 08/01/2014] [Indexed: 12/11/2022]
Abstract
Epigenetics refers to functional alterations in gene expression or phenotype without any change of the underlying DNA sequence. It is the study of the potential of a cell or organism to express different traits through functional regulation of its gene transcription. Though it is met as a necessary process in biology, epigenetics may often play a crucial part in the development of specific pathologic conditions, including cardiovascular diseases and hypertension.
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16
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Bild W, Hritcu L, Stefanescu C, Ciobica A. Inhibition of central angiotensin II enhances memory function and reduces oxidative stress status in rat hippocampus. Prog Neuropsychopharmacol Biol Psychiatry 2013; 43:79-88. [PMID: 23266710 DOI: 10.1016/j.pnpbp.2012.12.009] [Citation(s) in RCA: 60] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/05/2012] [Revised: 12/11/2012] [Accepted: 12/11/2012] [Indexed: 02/07/2023]
Abstract
While it is now well established that the independent brain renin-angiotensin system (RAS) has some important central functions besides the vascular ones, the relevance of its main bioactive peptide angiotensin II (Ang II) on the memory processes, as well as on oxidative stress status is not completely understood. The purpose of the present work was to evaluate the effects of central Ang II administration, as well as the effects of Ang II inhibition with either AT1 and AT 2 receptor specific blockers (losartan and PD-123177, respectively) or an angiotensin-converting enzyme (ACE) inhibitor (captopril). These effects were studied on the short-term memory (assessed through Y-maze) or long-term memory (as determined in passive avoidance) and on the oxidative stress status of the hippocampus. Our results demonstrate memory deficits induced by the administration of Ang II, as showed by the significant decrease of the spontaneous alternation in Y-maze (p=0.015) and latency-time in passive avoidance task (p=0.001) when compared to saline. On the other side, the administration of all the aforementioned Ang II blockers significantly improved the spontaneous alternation in Y-maze task, while losartan also increased the latency time as compared to saline in step-through passive avoidance (p=0.042). Also, increased oxidative stress status was induced in the hippocampus by the administration of Ang II, as demonstrated by increased levels of lipid peroxidation markers (malondialdehyde-MDA concentration) (p<0.0001) and a decrease in both antioxidant enzymes determined: superoxide dismutase-SOD (p<0.0001) and glutathione peroxidase-GPX (p=0.01), as compared to saline. Additionally, the administration of captopril resulted in an increase of both antioxidant enzymes and decreased levels of lipid peroxidation (p=0.001), while PD-123177 significantly decreased MDA concentration (p>0.0001) vs. saline. Moreover, significant correlations were found between all of the memory related behavioral parameters and the main oxidative stress markers from the hippocampus, which is known for its implication in the processes of memory and also where RAS components are well expressed. This could be relevant for the complex interactions between Ang II, behavioral processes and neuronal oxidative stress, and could generate important therapeutic approaches.
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Affiliation(s)
- Walther Bild
- Gr. T. Popa University of Medicine and Pharmacy, 16 Universitatii Street, 700115, Iasi, Romania
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17
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Bild W, Ciobica A. Angiotensin-(1-7) central administration induces anxiolytic-like effects in elevated plus maze and decreased oxidative stress in the amygdala. J Affect Disord 2013; 145:165-71. [PMID: 22868060 DOI: 10.1016/j.jad.2012.07.024] [Citation(s) in RCA: 45] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/12/2012] [Revised: 07/18/2012] [Accepted: 07/18/2012] [Indexed: 12/21/2022]
Abstract
There is increasing evidence that besides the well-known angiotensin (Ang) II, other renin-angiotensin system (RAS) peptides, including Ang-(1-7), could have important effects at the central level. However, very few things are known about the central actions of Ang-(1-7), while the effects of its administration alone on anxiety have not been tested to date, to the best of our knowledge. In this way, we were interested in studying the effects of Ang-(1-7) intracerebroventricular administration on anxiety levels, as studied through some main behavioral parameters in the elevated plus maze, as well as the importance of Ang-(1-7) in the oxidative stress status from the amygdala, which is one of the key brain regions involved in mediating anxiety. We report here a possible anxiolytic-like effect of Ang-(1-7) administration, as demonstrated by the increased percentage of time spent and frequency of entries in the open arms of the elevated plus maze, as well as increased head-dipping behavior in the open arms and decreased stretching in closed arms. Also some antioxidant effects of Ang-(1-7) are suggested since a significant increase of GPX specific activity and a decrease of the main peroxidation marker MDA were observed in the amygdala. Moreover, we found a significant correlation between most of the behavioral parameters in the elevated plus maze and the levels of the oxidative stress markers. However, further studies are necessary in order to elucidate the effects of Ang-(1-7) administration on anxiety and oxidative stress status and also on the possible correlation that might exists between these aspects.
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Affiliation(s)
- Walther Bild
- "Gr. T. Popa" University of Medicine and Pharmacy, 16 Universitatii Street, 700115 Iasi, Romania
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18
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Effects of angiotensin II receptor antagonists on anxiety and some oxidative stress markers in rat. Open Med (Wars) 2011. [DOI: 10.2478/s11536-011-0010-8] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
AbstractIn addition to its known classical roles, the renin angiotensin system (RAS) has more subtle functions which include the regulation of emotional responses. Previous studies regarding the anxiety related behavior of RAS have showed controversial results. There is also evidence that oxidative stress accompanies angiotensin II infusion, but the role of AT1/AT2 specific receptors is not clear. The aim of this study was to evaluate the effects of central angiotensin II receptor blockers on anxiety state and oxidative stress. Behavioral testing included elevated plus maze, while oxidative stress status was measured though the extent of a lipid peroxidation product (malondialdehyde-MDA) and the specific activity of some defense antioxidant enzymes (superoxide dismutase-SOD and glutathione peroxidase-GPx). The rats treated with angiotensin II spent significantly less time in the open-arms of elevated-plus-maze, while the administration of losartan resulted in a significant increase of this time. We observed a significant increase of MDA concentration in the angiotensin II group and a decrease of MDA levels in both losartan and PD-123177 groups. In addition, a significant correlation was seen between the time spent in the open arms and oxidative stress markers. These findings could lead to important therapeutic aspects regarding the use of angiotensin II receptor blockers in anxiety-related disorders.
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19
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Abstract
Epigenetics refers to mechanisms for environment-gene interactions (mainly by methylation of DNA and modification of histones) that do not alter the underlying base sequence of the gene. This article reviews evidence for epigenetic contributions to hypertension. For example, DNA methylation at CpG islands and histone acetylation pathways are known to limit nephron development, thereby unmasking hypertension associated with exposure to a high-salt diet. Maternal water deprivation and protein deficiency are shown to increase expression of renin-angiotensin system genes in the offspring. The methylation pattern of a serine protease inhibitor gene in human placentas is shown to be a marker for preeclampsia-associated hypertension. Mental stress induces phenylethanolamine n-methyltransferase, which may act as a DNA methylase and mimic the gene-silencing effects of methyl CpG binding protein-2 on the norepinephrine transporter gene, which, in turn, may exaggerate autonomic responsiveness. A disrupter of telomeric silencing (Dot1) is known to modulate the expression of a connective-tissue growth-factor gene associated with blood vessel remodeling, which could alter vascular compliance and elastance. Dot1a also interacts with the Af9 gene to produce high sodium channel permeability and silences the hydroxysteroid dehydrogenase-11β2 gene, thereby preventing metabolism of cortisol to cortisone and overstimulating aldosterone receptors. These findings indicate targets for environment-gene interactions in various hypertensive states and in essential hypertension.
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Affiliation(s)
- Richard M Millis
- Department of Physiology & Biophysics, Howard University College of Medicine, 520 "W" Street NW, Washington, DC 20059, USA.
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20
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López-Novoa JM, Bernabeu C. The physiological role of endoglin in the cardiovascular system. Am J Physiol Heart Circ Physiol 2010; 299:H959-74. [PMID: 20656886 DOI: 10.1152/ajpheart.01251.2009] [Citation(s) in RCA: 152] [Impact Index Per Article: 10.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Endoglin (CD105) is an integral membrane glycoprotein that serves as a coreceptor for members of the transforming growth factor-β superfamily of proteins. A major role for endoglin in regulating transforming growth factor-β-dependent vascular remodeling and angiogenesis has been postulated based on the following: 1) endoglin is the gene mutated in hereditary hemorrhagic telangiectasia type 1, a disease characterized by vascular malformations; 2) endoglin knockout mice die at midgestation because of defective angiogenesis; 3) endoglin is overexpressed in neoangiogenic vessels, during inflammation, and in solid tumors; and 4) endoglin regulates the expression and activity of endothelial nitric oxide synthase, which is involved in angiogenesis and vascular tone. Besides the predominant form of the endoglin receptor (long endoglin isoform), two additional forms of endoglin have been recently reported to play a role in the vascular pathology and homeostasis: the alternatively spliced short endoglin isoform and a soluble endoglin form that is proteolytically cleaved from membrane-bound endoglin. The purpose of this review is to underline the role that the different forms of endoglin play in regulating angiogenesis, vascular remodeling, and vascular tone, as well as to analyze the molecular and cellular mechanisms supporting these effects.
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Affiliation(s)
- José M López-Novoa
- Instituto Reina Sofía de Investigación Nefrológica, Departamento de Fisiologia y Farmacologia, Universidad de Salamanca, and Red de Investigación Renal, Instituto de Salud Carlos III, Salamanca, Spain.
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21
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Wang W, Pang L, Palade P. Angiotensin II upregulates Ca(V)1.2 protein expression in cultured arteries via endothelial H(2)O(2) production. J Vasc Res 2010; 48:67-78. [PMID: 20639649 DOI: 10.1159/000318776] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2009] [Accepted: 03/15/2010] [Indexed: 11/19/2022] Open
Abstract
BACKGROUND We previously reported that angiotensin II caused an endothelial-dependent increase in L-type voltage-dependent Ca(2+) channel (Ca(V)1.2) in cultured arteries, but the signaling pathways are not clear. METHODS Endothelial damage was generated by brief intra-arterial perfusion with 0.3% CHAPS. Ca(V)1.2 expression, function and H(2)O(2) were measured by Western blot, tension recording and Amplex Red H(2)O(2) assay kit, respectively. RESULTS Angiotensin II dose-dependently upregulated Ca(V)1.2 expression in endothelium-intact arteries. The angiotensin II upregulation of Ca(V)1.2 expression in endothelium-intact arteries was blocked by NAD(P)H oxidase inhibitor diphenyleneiodonium (DPI), apocynin, a more specific NAD(P)H oxidase inhibitor gp91ds-tat and also by catalase. H(2)O(2) similarly upregulated Ca(V)1.2 expression in endothelium-intact and endothelium-damaged arteries, and the latter effect was also blocked by DPI and apocynin. Angiotensin II increased H(2)O(2) production by endothelium-intact but not by endothelium-damaged arteries, and this effect was blocked by apocynin, catalase and gp91ds-tat. The upregulation of Ca(V)1.2 by angiotensin II and H(2)O(2) is accompanied by an increased tension response to KCl and the Ca(2+) channel activator FPL 64176, and this effect was also attenuated by gp91ds-tat. CONCLUSION These results suggest that angiotensin II stimulates endothelial NAD(P)H oxidase-produced H(2)O(2,) which may additionally act through vascular smooth muscle NAD(P)H oxidase, to upregulate vascular Ca(V)1.2 protein.
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Affiliation(s)
- Wenze Wang
- Department of Pharmaceutical Sciences, University of Arkansas for Medical Sciences, Little Rock, Ark 72205, USA. wwang @ uams.edu
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22
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Sheppard SJ, Khalil RA. Risk factors and mediators of the vascular dysfunction associated with hypertension in pregnancy. Cardiovasc Hematol Disord Drug Targets 2010; 10:33-52. [PMID: 20041838 DOI: 10.2174/187152910790780096] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2009] [Accepted: 12/24/2009] [Indexed: 01/24/2023]
Abstract
Normal pregnancy is associated with significant hemodynamic changes and vasodilation in the uterine and systemic circulation in order to meet the metabolic demands of the mother and developing fetus. Hypertension in pregnancy (HTN-Preg) and preeclampsia (PE) are major complications and life-threatening conditions to both the mother and fetus. PE is precipitated by various genetic, dietary and environmental factors. Although the initiating events of PE are unclear, inadequate invasion of cytotrophoblasts into the uterine artery is thought to reduce uteroplacental perfusion pressure and lead to placental ischemia/hypoxia. Placental hypoxia induces the release of biologically active factors such as growth factor inhibitors, anti-angiogenic proteins, inflammatory cytokines, reactive oxygen species, hypoxia-inducible factors, and antibodies to vascular angiotensin II receptor. These bioactive factors affect the production/activity of various vascular mediators in the endothelium, smooth muscle and extracellular matrix, leading to severe vasoconstriction and HTN. As an endothelial cell disorder, PE is associated with decreased vasodilator mediators such as nitric oxide, prostacyclin and hyperpolarizing factor and increased vasoconstrictor mediators such as endothelin, angiotensin II and thromboxane A(2). PE also involves enhanced mechanisms of vascular smooth muscle contraction including intracellular free Ca(2+) concentration ([Ca(2+)](i)), and [Ca(2+)](i) sensitization pathways such as protein kinase C, Rho-kinase and mitogen-activated protein kinase. Changes in extracellular matrix composition and matrix metalloproteases activity also promote vascular remodeling and further vasoconstriction in the uterine and systemic circulation. Characterization of the predisposing risk factors, the biologically active factors, and the vascular mediators associated with PE holds the promise for early detection, and should help design specific genetic and pharmacological tools for the management of the vascular dysfunction associated with HTN-Preg.
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Affiliation(s)
- Stephanie J Sheppard
- Division of Vascular and Endovascular Surgery, Brigham and Women's Hospital, and Harvard Medical School, Boston, Massachusetts 02115, USA
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23
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Tanbe AF, Khalil RA. Circulating and Vascular Bioactive Factors during Hypertension in Pregnancy. ACTA ACUST UNITED AC 2010; 6:60-75. [PMID: 20419111 DOI: 10.2174/157340710790711737] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Normal pregnancy is associated with significant vascular remodeling in the uterine and systemic circulation in order to meet the metabolic demands of the mother and developing fetus. The pregnancy-associated vascular changes are largely due to alterations in the amount/activity of vascular mediators released from the endothelium, vascular smooth muscle and extracellular matrix. The endothelium releases vasodilator substances such as nitric oxide, prostacyclin and hyperpolarizing factor as well as vasoconstrictor factors such as endothelin, angiotensin II and thromboxane A(2). Vascular smooth muscle contraction is mediated by intracellular free Ca(2+) concentration ([Ca(2+)](i)), and [Ca(2+)](i) sensitization pathways such as protein kinase C, Rho-kinase and mitogen-activated protein kinase. Extracellular matrix and vascular remodeling are regulated by matrix metalloproteases. Hypertension in pregnancy and preeclampsia are major complications and life threatening conditions to both the mother and fetus, precipitated by various genetic, dietary and environmental factors. The initiating mechanism of preeclampsia and hypertension in pregnancy is unclear; however, most studies have implicated inadequate invasion of cytotrophoblasts into the uterine artery, leading to reduction in the uteroplacental perfusion pressure and placental ischemia/hypoxia. This placental hypoxic state is thought to induce the release of several circulating bioactive factors such as growth factor inhibitors, anti-angiogenic proteins, inflammatory cytokines, reactive oxygen species, hypoxia-inducible factors, and vascular receptor antibodies. Increases in the plasma levels and vascular content of these factors during pregnancy could cause an imbalance in the vascular mediators released from the endothelium, smooth muscle and extracellular matrix, and lead to severe vasoconstriction and hypertension. This review will discuss the interactions between the various circulating bioactive factors and the vascular mediators released during hypertension in pregnancy, and provide an insight into the current and future approaches in the management of preeclampsia.
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Affiliation(s)
- Alain F Tanbe
- Division of Vascular and Endovascular Surgery, Brigham and Women's Hospital and Harvard Medical School, Boston, Massachusetts 02115
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24
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Baumann M, Leineweber K, Tewiele M, Wu K, Türk TR, Su S, Gössl M, Buck T, Wilde B, Heemann U, Kribben A, Witzke O. Imatinib ameliorates fibrosis in uraemic cardiac disease in BALB/c without improving cardiac function. Nephrol Dial Transplant 2010; 25:1817-24. [PMID: 20061323 DOI: 10.1093/ndt/gfp708] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
BACKGROUND Cardiovascular disease is one of the major causes of mortality and morbidity in patients with end-stage renal disease (ESRD). It is characterized by multiple left ventricular abnormalities, referred to as 'uraemic cardiomyopathy'. The aim of the study was to investigate uraemic cardiac disease in a mouse model of chronic renal failure induced by subtotal nephrectomy and to evaluate the impact of the tyrosine kinase inhibitor imatinib and its antifibrotic as well as functional properties on the extent of the disease. METHODS Male BALB/c mice were sham operated (SH) or subtotally nephrectomized and either left untreated (5/6) or treated with imatinib (5/6+I: 10 mg/kg/day p.o.) for up to 24 weeks. Cardiac and arterial structure and function were analysed using echocardiography, histology, extent of lipid peroxidation and myography, respectively. RESULTS Subtotal nephrectomy resulted in cardiac dysfunction characterized by reduced fractional shortening (SH: 21.6 +/- 4.7%; 5/6: 11.1 +/- 2.4%; 5/6+I: 8.4 +/- 2.7%; P < 0.05) and ejection fraction (SH: 38.8 +/- 4.5%; 5/6: 26.1 +/- 2.8%; 5/6+I: 18.6 +/- 2.6%; P < 0.05) after 24 weeks. This was associated with impaired endothelium-dependent vasodilatation in mesenteric resistance vessels and elevated cardiac malondialdehyde concentrations as a marker of lipid peroxidation. In this model, the continuous application of the tyrosine kinase inhibitor imatinib was associated with less myocardial fibrosis (SH: 2.52 +/- 0.34%; 5/6: 5.50 +/- 0.18%; 5/6+I: 3.52 +/- 0.52%; P < 0.05), but did not preserve myocardial function. CONCLUSIONS Uraemic cardiac disease in BALB/c results in fibrosis, oxidative damage and endothelial dysfunction. However, the anti-fibrotic activity of imatinib did not ameliorate cardiac dysfunction. Thus, our data suggest that uraemic cardiac disease in this mouse model is driven by oxidative damage and endothelial dysfunction.
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Affiliation(s)
- Marcus Baumann
- Department of Nephrology, Klinikum rechts der Isar, Technische Universität München, Germany
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25
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Abstract
The endothelial cell layer plays a major role in the development and progression of atherosclerosis. Endothelial NO synthase (eNOS) produces nitric oxide (NO) from L-arginine. NO can rapidly react with reactive oxygen species to form peroxynitrite. This reduces NO availability, impairs vasodilatation, and mediates proinflammatory and prothrombotic processes such as leukocyte adhesion and platelet aggregation. In the vessel wall, specific NAD(P)H oxidase complexes are major sources of reactive oxygen species. These NAD(P)H oxidases can transfer electrons across membranes to oxygen and generate superoxide anions. The short-lived superoxide anion rapidly dismutates to hydrogen peroxide, which can further increase the production of reactive oxygen species. This can lead to uncoupling of eNOS switching enzymatic activity from NO to superoxide production. This review describes the structure and regulation of different NAD(P)H oxidase complexes. We will also focus on NO/superoxide anion balance as modulated by hemodynamic forces, vasoconstrictors, and oxidized low-density lipoprotein. We will then summarize the recent advances defining the role of nitric oxide and NAD(P)H oxidase-derived reactive oxygen species in the development and progression of atherosclerosis. In conclusion, novel mechanisms affecting the vascular NO/superoxide anion balance will allow the development of therapeutic strategies in the treatment of cardiovascular diseases.
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Affiliation(s)
- Gregor Muller
- Department of Vascular Endothelium and Microcirculation, University of Technology Dresden, Dresden, Germany
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26
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Grgic I, Kaistha BP, Hoyer J, Köhler R. Endothelial Ca+-activated K+ channels in normal and impaired EDHF-dilator responses--relevance to cardiovascular pathologies and drug discovery. Br J Pharmacol 2009; 157:509-26. [PMID: 19302590 DOI: 10.1111/j.1476-5381.2009.00132.x] [Citation(s) in RCA: 152] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023] Open
Abstract
The arterial endothelium critically contributes to blood pressure control by releasing vasodilating autacoids such as nitric oxide, prostacyclin and a third factor or pathway termed 'endothelium-derived hyperpolarizing factor' (EDHF). The nature of EDHF and EDHF-signalling pathways is not fully understood yet. However, endothelial hyperpolarization mediated by the Ca(2+)-activated K(+) channels (K(Ca)) has been suggested to play a critical role in initializing EDHF-dilator responses in conduit and resistance-sized arteries of many species including humans. Endothelial K(Ca) currents are mediated by the two K(Ca) subtypes, intermediate-conductance K(Ca) (KCa3.1) (also known as, a.k.a. IK(Ca)) and small-conductance K(Ca) type 3 (KCa2.3) (a.k.a. SK(Ca)). In this review, we summarize current knowledge about endothelial KCa3.1 and KCa2.3 channels, their molecular and pharmacological properties and their specific roles in endothelial function and, particularly, in the EDHF-dilator response. In addition we focus on recent experimental evidences derived from KCa3.1- and/or KCa2.3-deficient mice that exhibit severe defects in EDHF signalling and elevated blood pressures, thus highlighting the importance of the KCa3.1/KCa2.3-EDHF-dilator system for blood pressure control. Moreover, we outline differential and overlapping roles of KCa3.1 and KCa2.3 for EDHF signalling as well as for nitric oxide synthesis and discuss recent evidence for a heterogeneous (sub) cellular distribution of KCa3.1 (at endothelial projections towards the smooth muscle) and KCa2.3 (at inter-endothelial borders and caveolae), which may explain their distinct roles for endothelial function. Finally, we summarize the interrelations of altered KCa3.1/KCa2.3 and EDHF system impairments with cardiovascular disease states such as hypertension, diabetes, dyslipidemia and atherosclerosis and discuss the therapeutic potential of KCa3.1/KCa2.3 openers as novel types of blood pressure-lowering drugs.
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Affiliation(s)
- Ivica Grgic
- Department of Internal Medicine-Nephrology, Philipps-University, Marburg, Germany
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27
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Wilcox CS, Pearlman A. Chemistry and antihypertensive effects of tempol and other nitroxides. Pharmacol Rev 2009; 60:418-69. [PMID: 19112152 DOI: 10.1124/pr.108.000240] [Citation(s) in RCA: 290] [Impact Index Per Article: 19.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
Nitroxides can undergo one- or two-electron reduction reactions to hydroxylamines or oxammonium cations, respectively, which themselves are interconvertible, thereby providing redox metabolic actions. 4-Hydroxy-2,2,6,6-tetramethylpiperidine-N-oxyl (tempol) is the most extensively studied nitroxide. It is a cell membrane-permeable amphilite that dismutates superoxide catalytically, facilitates hydrogen peroxide metabolism by catalase-like actions, and limits formation of toxic hydroxyl radicals produced by Fenton reactions. It is broadly effective in detoxifying these reactive oxygen species in cell and animal studies. When administered intravenously to hypertensive rodent models, tempol caused rapid and reversible dose-dependent reductions in blood pressure in 22 of 26 studies. This was accompanied by vasodilation, increased nitric oxide activity, reduced sympathetic nervous system activity at central and peripheral sites, and enhanced potassium channel conductance in blood vessels and neurons. When administered orally or by infusion over days or weeks to hypertensive rodent models, it reduced blood pressure in 59 of 68 studies. This was accompanied by correction of salt sensitivity and endothelial dysfunction and reduced agonist-evoked oxidative stress and contractility of blood vessels, reduced renal vascular resistance, and increased renal tissue oxygen tension. Thus, tempol is broadly effective in reducing blood pressure, whether given by acute intravenous injection or by prolonged administration, in a wide range of rodent models of hypertension.
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Affiliation(s)
- Christopher S Wilcox
- Division of Nephrology and Hypertension, Kidney and Vascular Disorder Center, Georgetown University, Washington, DC 20007, USA.
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28
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Abstract
NADPH oxidases have recently been shown to contribute to the pathogenesis of hypertension. The development of specific inhibitors of these enzymes has focused attention on their potential therapeutic use in hypertensive disease. Two of the most specific inhibitors, gp91ds-tat and apocynin, have been shown to decrease blood pressure in animal models of hypertension. Other inhibitors, including diphenylene iodonium, aminoethyl benzenesulfono fluoride, S17834, PR39, protein kinase C inhibitors, and VAS2870, have shown promise in vitro, but their in vivo specificity, pharmacokinetics, and effectiveness in hypertension remains to be determined. Of importance, the currently available antihypertensive agents angiotensin-converting enzyme inhibitors and angiotensin receptor blockers also effectively inhibit NADPH oxidase activation. Similarly, the cholesterol-lowering agents, statins, have been shown to attenuate NADPH oxidase activation. Although, antioxidants act to scavenge the reactive oxygen species produced by these enzymes, their effectiveness is limited. Targeting NADPH homologues may have a distinct advantage over current therapies because it would specifically prevent the pathophysiological formation of reactive oxygen species that contributes to hypertension.
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Affiliation(s)
- Holly C Williams
- Division of Cardiology, Emory University, Atlanta, GA 30322, USA
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29
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Cherney DZI, Scholey JW, Cattran DC, Kang AK, Zimpelmann J, Kennedy C, Lai V, Burns KD, Miller JA. The effect of oral contraceptives on the nitric oxide system and renal function. Am J Physiol Renal Physiol 2007; 293:F1539-44. [PMID: 17715260 DOI: 10.1152/ajprenal.00351.2007] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
We have demonstrated that oral contraceptive (OC) users exhibit elevated angiotensin II levels and angiotensin II type 1 receptor expression, indicative of renin-angiotensin system (RAS) activation, yet the renal and systemic consequences are minimal, suggesting that there is increased vasodilatory activity, counteracting the effect of RAS activation. We hypothesized that the nitric oxide (NO) system would be upregulated in OC users and that this would be reflected by a blunted hemodynamic response to l-arginine infusion. All subjects were studied after a 7-day controlled sodium and protein diet. Inulin and para-aminohippurate clearance techniques were used to assess renal function. l-Arginine was infused at 100, 250, and 500 mg/kg, each over 30 min. Skin endothelial NO synthase mRNA expression was assessed by real-time PCR. While OC nonusers exhibited significant increases in effective renal plasma flow (670.8 +/- 35.6 to 816.2 +/- 59.7 ml.min(-1).1.73 m(-2)) and glomerular filtration rate (133.4 +/- 4.3 to 151.0 +/- 5.7 ml.min(-1).1.73 m(-2), P = 0.04) and declines in renal vascular resistance (81.1 +/- 6.1 to 63.5 +/- 6.2 mmHg.ml(-1).min, P = 0.001) at the lower l-arginine infusion rates, the responses in OC users were blunted. While l-arginine reduced mean arterial pressure at the 250 and 500 mg/kg doses in OC nonusers, OC users only exhibited a decrease in mean arterial pressure at the highest infusion rate. In contrast, tissue endothelial NO synthase mRNA levels were higher in the OC users (P = 0.04). In summary, these findings suggest that the NO system is upregulated by OC use in young, healthy women. Increased activity of the NO pathway may modulate the hemodynamic effects of RAS activation in OC users.
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Affiliation(s)
- D Z I Cherney
- Division of Nephrology, Toronto General Hospital, University of Toronto, Toronto
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30
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Wang D, Gill PS, Chabrashvili T, Onozato ML, Raggio J, Mendonca M, Dennehy K, Li M, Modlinger P, Leiper J, Vallance P, Adler O, Leone A, Tojo A, Welch WJ, Wilcox CS. Isoform-specific regulation by N(G),N(G)-dimethylarginine dimethylaminohydrolase of rat serum asymmetric dimethylarginine and vascular endothelium-derived relaxing factor/NO. Circ Res 2007; 101:627-35. [PMID: 17673667 DOI: 10.1161/circresaha.107.158915] [Citation(s) in RCA: 110] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Asymmetric dimethylarginine (ADMA), which inhibits NO synthase, is inactivated by N(G),N(G)-dimethylarginine dimethylaminohydrolase (DDAH). We tested whether DDAH-1 or -2 regulates serum ADMA (S(ADMA)) and/or endothelium-derived relaxing factor (EDRF)/NO. Small inhibitory (si)RNAs targeting DDAH-1 or -2, or an siRNA control were given intravenously to rats. After 72 hours, EDRF/NO was assessed from acetylcholine-induced, NO synthase-dependent relaxation and 4-amino-5-methylamino-2',7'-difluorofluorescein diacetate for NO activity in isolated mesenteric resistance vessels (MRVs). Expression of mRNA for DDAH-1 versus -2 was 2- and 7-fold higher in the kidney cortex and liver, respectively, whereas expression of DDAH-2 versus -1 was 5-fold higher in MRVs. The proteins and mRNAs for DDAH-1 or -2 were reduced selectively by 35% to 85% in the kidney cortex, liver, and MRVs 72 hours following the corresponding siRNA. S(ADMA) was increased only after siDDAH-1 (266+/-25 versus 342+/-39 [mean+/-SD] nmol x L(-1); P<0.005), whereas EDRF/NO responses and NO activity were not changed consistently by siDDAH-1 but were greatly reduced after siDDAH-2. Mean arterial pressure was not changed significantly by any siRNA. In conclusion, S(ADMA) is regulated by DDAH-1, which is expressed at sites of ADMA metabolism in the kidney cortex and liver, whereas EDRF/NO is regulated primarily by DDAH-2, which is expressed strongly in blood vessels. This implies specific functions of DDAH isoforms.
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Affiliation(s)
- Dan Wang
- Division of Nephrology and Hypertension, Georgetown University, Washington, DC 20007, USA
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31
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Chen Y, Pearlman A, Luo Z, Wilcox CS. Hydrogen peroxide mediates a transient vasorelaxation with tempol during oxidative stress. Am J Physiol Heart Circ Physiol 2007; 293:H2085-92. [PMID: 17644566 DOI: 10.1152/ajpheart.00968.2006] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Tempol catalyzes the formation of H(2)O(2) from superoxide and relaxes blood vessels. We tested the hypothesis that the generation of H(2)O(2) by tempol in vascular smooth muscle cells during oxidative stress contributes to the vasorelaxation. Tempol and nitroblue tetrazolium (NBT) both metabolize superoxide in vascular smooth muscle cells, but only tempol generates H(2)O(2). Rat pressurized mesenteric arteries were exposed for 20 min to the thromboxane-prostanoid receptor agonist, U-46619, or norepinephrine. During U-46619, tempol caused a transient dilation (22 +/- 2%), whereas NBT was ineffective (2 +/- 1%), and neither dilated vessels constricted with norepinephrine, which does not cause vascular oxidative stress. Neither endothelium removal nor blockade of K(+) channels with 40 mM KCl affected the tempol-induced dilation, but catalase blunted the tempol dilation by 53 +/- 7%. Tempol, but not NBT, increased H(2)O(2) in rat mesenteric vessels detected with dichlorofluorescein. To test physiological relevance in vivo, topical application of tempol caused a transient dilation (184 +/- 20%) of mouse cremaster arterioles exposed to angiotensin II for 30 min, which was not seen with NBT (9 +/- 4%). The vasodilation to tempol was reduced by 68 +/- 6% by catalase. We conclude that the transient relaxation of blood vessels by tempol after prolonged exposure to U-46619 or angiotensin II is mediated in part via production of H(2)O(2) and is largely independent of the endothelium and potassium channels.
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MESH Headings
- 15-Hydroxy-11 alpha,9 alpha-(epoxymethano)prosta-5,13-dienoic Acid/pharmacology
- Angiotensin II/metabolism
- Animals
- Antioxidants/pharmacology
- Catalase/metabolism
- Cells, Cultured
- Cyclic N-Oxides/pharmacology
- Dose-Response Relationship, Drug
- Endothelium, Vascular/drug effects
- Endothelium, Vascular/metabolism
- Hydrogen Peroxide/metabolism
- In Vitro Techniques
- Male
- Mesenteric Arteries/drug effects
- Mesenteric Arteries/metabolism
- Mice
- Muscle, Smooth, Vascular/drug effects
- Muscle, Smooth, Vascular/enzymology
- Muscle, Smooth, Vascular/metabolism
- Myocytes, Smooth Muscle/drug effects
- Myocytes, Smooth Muscle/enzymology
- Myocytes, Smooth Muscle/metabolism
- Nitroblue Tetrazolium/pharmacology
- Norepinephrine/pharmacology
- Oxidative Stress/drug effects
- Potassium Channels/drug effects
- Potassium Channels/metabolism
- Rats
- Rats, Inbred SHR
- Spin Labels
- Superoxide Dismutase/metabolism
- Superoxides/metabolism
- Vasoconstrictor Agents/pharmacology
- Vasodilation/drug effects
- Vasodilator Agents/pharmacology
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Affiliation(s)
- Yifan Chen
- Cardiovascular Kidney Hypertension Institute, Division of Nephrology & Hypertension, Georgetown Univ., 4000 Reservoir Road, NW, Bldg. D-399, Washington, DC 20057, USA.
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Toda N, Ayajiki K, Okamura T. Interaction of Endothelial Nitric Oxide and Angiotensin in the Circulation. Pharmacol Rev 2007; 59:54-87. [PMID: 17329548 DOI: 10.1124/pr.59.1.2] [Citation(s) in RCA: 49] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
Discovery of the unexpected intercellular messenger and transmitter nitric oxide (NO) was the highlight of highly competitive investigations to identify the nature of endothelium-derived relaxing factor. This labile, gaseous molecule plays obligatory roles as one of the most promising physiological regulators in cardiovascular function. Its biological effects include vasodilatation, increased regional blood perfusion, lowering of systemic blood pressure, and antithrombosis and anti-atherosclerosis effects, which counteract the vascular actions of endogenous angiotensin (ANG) II. Interactions of these vasodilator and vasoconstrictor substances in the circulation have been a topic that has drawn the special interest of both cardiovascular researchers and clinicians. Therapeutic agents that inhibit the synthesis and action of ANG II are widely accepted to be essential in treating circulatory and metabolic dysfunctions, including hypertension and diabetes mellitus, and increased availability of NO is one of the most important pharmacological mechanisms underlying their beneficial actions. ANG II provokes vascular actions through various receptor subtypes (AT1, AT2, and AT4), which are differently involved in NO synthesis and actions. ANG II and its derivatives, ANG III, ANG IV, and ANG-(1-7), alter vascular contractility with different mechanisms of action in relation to NO. This review article summarizes information concerning advances in research on interactions between NO and ANG in reference to ANG receptor subtypes, radical oxygen species, particularly superoxide anions, ANG-converting enzyme inhibitors, and ANG receptor blockers in patients with cardiovascular disease, healthy individuals, and experimental animals. Interactions of ANG and endothelium-derived relaxing factor other than NO, such as prostaglandin I2 and endothelium-derived hyperpolarizing factor, are also described.
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Affiliation(s)
- Noboru Toda
- Department of Pharmacology, Shiga University of Medical Science, Seta, Otsu, Japan.
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Kang KT, Sullivan JC, Sasser JM, Imig JD, Pollock JS. Novel nitric oxide synthase--dependent mechanism of vasorelaxation in small arteries from hypertensive rats. Hypertension 2007; 49:893-901. [PMID: 17309950 DOI: 10.1161/01.hyp.0000259669.40991.1e] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
To determine the mechanism(s) involved in vasorelaxation of small arteries from hypertensive rats, normotensive (NORM), angiotensin II-infused (ANG), high-salt (HS), ANG high-salt (ANG/HS), placebo, and deoxycorticosterone acetate-salt rats were studied. Third-order mesenteric arteries from ANG or ANG/HS displayed decreased sensitivity to acetylcholine (ACh)-induced vasorelaxation compared with NORM or HS, respectively. Maximal relaxations were comparable between groups. Blockade of Ca(2+)-activated K(+) channels had no effect on ANG versus blunting relaxation in NORM (log EC(50): -6.8+/-0.1 versus -7.2+/-0.1 mol/L). NO synthase (NOS) inhibition abolished ACh-mediated relaxation in small arteries from ANG, ANG/HS, and deoxycorticosterone acetate-salt versus blunting relaxation in NORM, HS, and placebo (% maximal relaxation: ANG: 2.7+/-1.8; ANG/HS: 7.2+/-3.2; NORM: 91+/-3.1; HS: 82.1+/-13.3; deoxycorticosterone acetate-salt: 35.2+/-17.7; placebo: 79.3+/-10.3), indicating that NOS is the primary vasorelaxation pathway in these arteries from hypertensive rats. We hypothesized that NO/cGMP signaling and NOS-dependent H(2)O(2) maintains vasorelaxation in small arteries from ANG. ACh increased NOS-dependent cGMP production, indicating that NO/cGMP signaling is present in small arteries from ANG (55.7+/-6.9 versus 30.5+/-5.1 pmol/mg), and ACh stimulated NOS-dependent H(2)O(2) production (ACh: 2.8+/-0.2 micromol/mg; N(omega)-nitro-l-arginine methyl ester hydrochloride+ACh: 1.8+/-0.1 micromol/mg) in small arteries from ANG. H(2)O(2) induced vasorelaxation and catalase blunted ACh-mediated vasorelaxation. In conclusion, Ca(2+)-activated K(+) channel-mediated relaxation is dysfunctional in small mesenteric arteries from hypertensive rats, and the NOS pathway compensates to maintain vasorelaxation in these arteries through NOS-mediated cGMP and H(2)O(2) production.
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Affiliation(s)
- Kyu-Tae Kang
- Vascular Biology Center, Medical College of Georgia, Augusta, GA 30912, USA
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Ford WR. Interpreting antioxidant responses to angiotensin AT1 receptor antagonists: pharmacology or chemistry? J Hypertens 2006; 24:1013-6. [PMID: 16685197 DOI: 10.1097/01.hjh.0000226187.83192.da] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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