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Dashwood MR, Loesch A. Endothelin-1, endothelin receptor antagonists, and vein graft occlusion in coronary artery bypass surgery: 20 years on and still no journey from bench to bedside. Can J Physiol Pharmacol 2020; 98:570-578. [PMID: 32343914 DOI: 10.1139/cjpp-2019-0598] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
The saphenous vein is the most commonly used bypass graft in patients with coronary artery disease. During routine coronary artery bypass, grafting the vascular damage inflicted on the vein is likely to stimulate the release of endothelin-1, a potent endothelium-derived vasoconstrictor that also possesses cell proliferation and inflammatory properties, conditions associated with vein graft failure. In both in vitro and in vivo studies, endothelin receptor antagonists reduce neointimal thickening. The mechanisms underlying these observations are multifactorial and include an effect on cell proliferation and cell/tissue damage. Much of the data supporting the beneficial action of endothelin-1 receptor antagonism at reducing intimal thickening and occlusion in experimental vein grafts were published over 20 years ago. The theme of the recent ET-16 conference in Kobe was "Visiting Old and Learning New". This short review article provides an overview of studies showing the potential of endothelin receptor antagonists to offer an adjuvant therapeutic approach for reducing saphenous vein graft failure and poses the question why this important area of research has not been translated from bench to bedside given the potential benefit for coronary artery bypass patients.
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Affiliation(s)
- Michael R Dashwood
- Surgical and Interventional Sciences, Royal Free Hospital Campus, University College Medical School, London, United Kingdom
| | - Andrzej Loesch
- Centre for Rheumatology, Royal Free Hospital Campus, University College Medical School, London, United Kingdom
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2
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Joddar B, Firstenberg MS, Reen RK, Varadharaj S, Khan M, Childers RC, Zweier JL, Gooch KJ. Arterial levels of oxygen stimulate intimal hyperplasia in human saphenous veins via a ROS-dependent mechanism. PLoS One 2015; 10:e0120301. [PMID: 25799140 PMCID: PMC4370681 DOI: 10.1371/journal.pone.0120301] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2014] [Accepted: 02/05/2015] [Indexed: 11/19/2022] Open
Abstract
Saphenous veins used as arterial grafts are exposed to arterial levels of oxygen partial pressure (pO2), which are much greater than what they experience in their native environment. The object of this study is to determine the impact of exposing human saphenous veins to arterial pO2. Saphenous veins and left internal mammary arteries from consenting patients undergoing coronary artery bypass grafting were cultured ex vivo for 2 weeks in the presence of arterial or venous pO2 using an established organ culture model. Saphenous veins cultured with arterial pO2 developed intimal hyperplasia as evidenced by 2.8-fold greater intimal area and 5.8-fold increase in cell proliferation compared to those freshly isolated. Saphenous veins cultured at venous pO2 or internal mammary arteries cultured at arterial pO2 did not develop intimal hyperplasia. Intimal hyperplasia was accompanied by two markers of elevated reactive oxygen species (ROS): increased dihydroethidium associated fluorescence (4-fold, p<0.05) and increased levels of the lipid peroxidation product, 4-hydroxynonenal (10-fold, p<0.05). A functional role of the increased ROS saphenous veins exposed to arterial pO2 is suggested by the observation that chronic exposure to tiron, a ROS scavenger, during the two-week culture period, blocked intimal hyperplasia. Electron paramagnetic resonance based oximetry revealed that the pO2 in the wall of the vessel tracked that of the atmosphere with a ~30 mmHg offset, thus the cells in the vessel wall were directly exposed to variations in pO2. Monolayer cultures of smooth muscle cells isolated from saphenous veins exhibited increased proliferation when exposed to arterial pO2 relative to those cultured at venous pO2. This increased proliferation was blocked by tiron. Taken together, these data suggest that exposure of human SV to arterial pO2 stimulates IH via a ROS-dependent pathway.
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Affiliation(s)
- Binata Joddar
- Department of Biomedical Engineering at The Ohio State University, Columbus, OH 43210, United States of America
- Davis Heart & Lung Research Institute at The Ohio State University, Columbus, OH 43210, United States of America
| | - Michael S. Firstenberg
- Division of Cardiothoracic Surgery at The Ohio State University, Columbus, OH 43210, United States of America
| | - Rashmeet K. Reen
- Department of Biomedical Engineering at The Ohio State University, Columbus, OH 43210, United States of America
- Davis Heart & Lung Research Institute at The Ohio State University, Columbus, OH 43210, United States of America
| | - Saradhadevi Varadharaj
- Davis Heart & Lung Research Institute at The Ohio State University, Columbus, OH 43210, United States of America
| | - Mahmood Khan
- Davis Heart & Lung Research Institute at The Ohio State University, Columbus, OH 43210, United States of America
- Department of Emergency Medicine at The Ohio State University, Columbus, OH 43210, United States of America
| | - Rachel C. Childers
- Department of Biomedical Engineering at The Ohio State University, Columbus, OH 43210, United States of America
- Davis Heart & Lung Research Institute at The Ohio State University, Columbus, OH 43210, United States of America
| | - Jay L. Zweier
- Davis Heart & Lung Research Institute at The Ohio State University, Columbus, OH 43210, United States of America
| | - Keith J. Gooch
- Department of Biomedical Engineering at The Ohio State University, Columbus, OH 43210, United States of America
- Davis Heart & Lung Research Institute at The Ohio State University, Columbus, OH 43210, United States of America
- * E-mail:
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3
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Xie P, Shi E, Gu T, Zhang Y, Mao N. Inhibition of intimal hyperplasia of the vein graft with degradable poly lactic-co-glycolic acid vascular external sheaths carrying slow-release bosentan. Eur J Cardiothorac Surg 2015; 48:842-9; discussion 849. [DOI: 10.1093/ejcts/ezv025] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/14/2014] [Accepted: 12/11/2014] [Indexed: 11/14/2022] Open
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Dashwood MR, Tsui JC. 'No-touch' saphenous vein harvesting improves graft performance in patients undergoing coronary artery bypass surgery: a journey from bedside to bench. Vascul Pharmacol 2012; 58:240-50. [PMID: 22967905 DOI: 10.1016/j.vph.2012.07.008] [Citation(s) in RCA: 50] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2012] [Revised: 07/14/2012] [Accepted: 07/31/2012] [Indexed: 11/19/2022]
Abstract
The saphenous vein is the most commonly used conduit in patients undergoing coronary artery bypass surgery yet its patency is inferior to the internal thoracic artery. Vascular damage inflicted to the vein when using conventional harvesting techniques affects its structure. Endothelial denudation is associated with early vein graft failure while damage of the outermost vessel layers has adverse long-term effects on graft performance. While many in vitro and in vivo experimental studies aimed at improving vein graft patency have been performed to date no significant 'bench to bedside' advances have been made. Among experimental strategies employed is the use of pharmacological agents, gene targeting and external stents. A 'no-touch' technique, where the saphenous vein is removed with minimal trauma and normal architecture preserved, produces a superior graft with long term patency comparable to the internal thoracic artery. Interestingly, many experimental studies are aimed at repairing or replacing those regions of the saphenous vein damaged when harvesting conventionally. 'No-touch' harvesting is superior in coronary artery bypass patients with long-term data published 5years ago. Here we describe a 'bedside to bench' situation where the mechanisms underlying the improved performance of 'no touch' saphenous vein grafts in patients have been studied in the laboratory.
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Affiliation(s)
- Michael R Dashwood
- Department of Clinical Biochemistry, Royal Free and University College Medical School, Pond Street, London NW3 2QG, United Kingdom.
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Wiedemann D, Kocher A, Bonaros N, Semsroth S, Laufer G, Grimm M, Schachner T. Perivascular administration of drugs and genes as a means of reducing vein graft failure. Curr Opin Pharmacol 2012; 12:203-16. [DOI: 10.1016/j.coph.2012.02.012] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2011] [Revised: 02/20/2012] [Accepted: 02/23/2012] [Indexed: 01/21/2023]
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Macitentan (ACT-064992), a tissue-targeting endothelin receptor antagonist, enhances therapeutic efficacy of paclitaxel by modulating survival pathways in orthotopic models of metastatic human ovarian cancer. Neoplasia 2011; 13:167-79. [PMID: 21403842 DOI: 10.1593/neo.10806] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2010] [Revised: 10/18/2010] [Accepted: 10/22/2010] [Indexed: 11/18/2022] Open
Abstract
Potential treatments for ovarian cancers that have become resistant to standard chemotherapies include modulators of tumor cell survival, such as endothelin receptor (ETR) antagonist. We investigated the therapeutic efficacy of the dual ETR antagonist, macitentan, on human ovarian cancer cells, SKOV3ip1 and IGROV1, growing orthotopically in nude mice. Mice with established disease were treated with vehicle (control), paclitaxel (weekly, intraperitoneal injections), macitentan (daily oral administrations), or a combination of paclitaxel and macitentan. Treatment with paclitaxel decreased tumor weight and volume of ascites. Combination therapy with macitentan and paclitaxel reduced tumor incidence and further reduced tumor weight and volume of ascites when compared with paclitaxel alone. Macitentan alone occasionally reduced tumor weight but alone had no effect on tumor incidence or ascites. Immunohistochemical analyses revealed that treatment with macitentan and macitentan plus paclitaxel inhibited the phosphorylation of ETRs and suppressed the survival pathways of tumor cells by decreasing the levels of pVEGFR2, pAkt, and pMAPK. The dose of macitentan necessary for inhibition of phosphorylation correlated with the dose required to increase antitumor efficacy of paclitaxel. Treatment with macitentan enhanced the cytotoxicity mediated by paclitaxel as measured by the degree of apoptosis in tumor cells and tumor-associated endothelial cells. Collectively, these results show that administration of macitentan in combination with paclitaxel prevents the progression of ovarian cancer in the peritoneal cavity of nude mice in part by inhibiting survival pathways of both tumor cells and tumor-associated endothelial cells.
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Joddar B, Shaffer RJG, Reen RK, Gooch KJ. Arterial pO₂ stimulates intimal hyperplasia and serum stimulates inward eutrophic remodeling in porcine saphenous veins cultured ex vivo. Biomech Model Mechanobiol 2010; 10:161-75. [PMID: 20512609 DOI: 10.1007/s10237-010-0224-8] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2009] [Accepted: 05/03/2010] [Indexed: 10/19/2022]
Abstract
Ex vivo culture of arteries and veins is an established tool for investigating mechanically induced remodeling. Porcine saphenous veins (PSV) cultured ex vivo with a venous mechanical environment, serum-supplemented cell-culture medium and standard cell-culture conditions (5% CO₂ and 95% balance air ~140 mmHg pO₂) develop intimal hyperplasia (IH), increased cellular proliferation, decreased compliance and exhibit inward eutrophic remodeling thereby suggesting that nonmechanical factors stimulate some changes observed ex vivo. Herein we explore the contribution of exposure to greater than venous pO₂ and serum to these changes in cultured veins. Removing serum from culture medium did not inhibit development of IH, but did reduce cellular proliferation and inward eutrophic remodeling. In contrast, veins perfused using reduced pO₂ (75 mmHg) showed reduced IH. Among the statically cultured vessels, veins cultured at arterial pO₂ (95 mmHg) and above showed IH as well as increase in proliferation and vessel weight compared to fresh veins; veins cultured at venous pO₂ did not. Taken together, these data suggest that exposure of SV to arterial pO₂ stimulates IH and cellular proliferation independent of changes in the mechanical environment, which might provide insight into the etiology of IH in SV used as arterial grafts.
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Affiliation(s)
- Binata Joddar
- Department of Biomedical Engineering, Ohio State University, 1080 Carmack Road, Columbus, OH 43210, USA
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8
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Aubert JD, Juillerat-Jeanneret L. Therapeutic potential of endothelin receptor modulators: lessons from human clinical trials. Expert Opin Ther Targets 2009; 13:1069-84. [PMID: 19659448 DOI: 10.1517/14728220903074570] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
The endothelin system, and in particular endothelin receptors, are targets for therapeutic intervention in human diseases. Endothelin receptor antagonists have reached clinical use for treating pulmonary arterial hypertension, and are under clinical investigation for several other diseases, such as cancer, vasospasm or fibrogenic diseases. We review the molecules that have been evaluated in the main clinical trials, from the point of view of receptor selectivity and of their chemical characteristics which were important for efficacy in pulmonary hypertension. We will also discuss future use of antagonists to endothelin receptor(s) in several human diseases and what should be the necessary properties of the future molecules for efficacy in diseases where the presently tested molecules displayed suboptimal efficacy.
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Affiliation(s)
- John-David Aubert
- University Institute of Pathology, University of Lausanne (UNIL), Centre Hospitalier Universitaire Vaudois (CHUV), Lausanne, Switzerland
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9
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Kitada K, Yui N, Matsumoto C, Mori T, Ohkita M, Matsumura Y. Inhibition of endothelin ETB receptor system aggravates neointimal hyperplasia after balloon injury of rat carotid artery. J Pharmacol Exp Ther 2009; 331:998-1004. [PMID: 19737855 DOI: 10.1124/jpet.109.157065] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Endothelin-1 (ET)/ET(A) receptor system has been known to play an important role in the pathogenesis of neointimal hyperplasia after endothelial injury. However, the pathological role of endothelin ET(B) receptors on neointimal hyperplasia remains to be elucidated. In the present study, we investigated the pathological role of ET(B) receptors on neointimal hyperplasia in balloon-injured rat carotid arteries by pharmacological blockade with use of 2R-(4-propoxyphenyl)-4S-(1,3-benzodioxol-5-yl)-1-(N-(2,6-diethylphenyl)aminocarbonyl-methyl)-pyrrolidine-3R-carboxylic acid (A-192621), a selective ET(B) receptor antagonist, 2R-(4-methoxyphenyl)-4S-(1,3-benzodioxol-5-yl)-1-(N,N-di(n-butyl)aminocarbonyl-methyl)-pyrrolidine-3R-carboxylic acid (ABT-627), a selective ET(A) receptor antagonist, and (+)-(5S,6R,7R)-2-butyl-7-[2-((2S)-2-carboxypropyl)-4-methoxyphenyl]-5-(3,4-methylenedioxyphenyl)cyclopenteno[1,2-b]pyridine-6-carboxylic acid (J-104132), an ET(A)/ET(B) dual receptor antagonist. Moreover, the spotting-lethal rats, which carry a naturally occurring deletion in the endothelin ET(B) receptor gene, were used to examine the effects of genetic deficiency for this receptor subtype. Two weeks after balloon injury, the ratio of the neointimal to the medial area (neointima/media ratio) was determined. Treatment with A-192621 (30 mg/kg/day) for 2 weeks after injury significantly increased the neointima/media ratio in the injured artery. In contrast, ABT-627 (10 mg/kg/day) and J-104132 (10 mg/kg/day) markedly decreased the neointima/media ratio to the same extent. Furthermore, the neointima/media ratio in the injured artery of the ET(B)-deficient rat was significantly increased compared with that of the wild-type rat, and this increase was abolished by treatment with J-104132. These findings suggest that the inhibition of the ET(B) receptor system leads to an aggravation of neointimal hyperplasia after balloon injury, and the augmentation of ET(A)-mediated actions are responsible for the neointimal hyperplasia aggravated by the pharmacological blockade of ET(B) receptor or by its genetic deficiency. The antagonism of the ET(A) receptor system is essential for preventing restenosis after angioplasty.
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Affiliation(s)
- Kento Kitada
- Laboratory of Pathological and Molecular Pharmacology, Osaka University of Pharmaceutical Sciences, 4-20-1 Nasahara, Takatsuki, Osaka 569-1094, Japan
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10
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Abstract
The saphenous vein is the most commonly used graft for revascularization procedures in patients with coronary artery disease and critical limb ischaemia. However, the patency rate of this vessel is poor, with a high proportion of patients requiring further surgery. Early graft occlusion is caused by vasoconstriction or thrombus formation, with later stages of graft failure being due to neointimal formation or atherosclerosis. Apart from its potent constrictor action, endothelin-1 is also a potent proliferative and proinflammatory peptide that is implicated in a number of vascular diseases. The surgical trauma caused during preparation of the saphenous vein as a bypass graft stimulates the release of a number of factors affecting vascular reactivity and structure, including endothelin-1. Endothelin-1 not only constricts animal and human isolated saphenous vein segments but also causes vascular smooth muscle proliferation and neointimal thickening in vitro, actions that are mediated via endothelin (A and B) receptors. Experimentally, the effects of subtype-selective and dual receptor antagonists have been shown to inhibit endothelin-1-mediated constriction and cell proliferation of the saphenous vein. In this review, data supporting a role of endothelin-1 in vein graft occlusion are presented, and the therapeutic potential of endothelin receptor antagonists in improving graft performance is discussed.
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Affiliation(s)
- M R Dashwood
- Royal Free and University College Medical School, London, UK.
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11
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Kassimatis TI, Konstantinopoulos PA. The role of statins in chronic kidney disease (CKD): Friend or foe? Pharmacol Ther 2009; 122:312-23. [DOI: 10.1016/j.pharmthera.2009.03.008] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2009] [Accepted: 03/20/2009] [Indexed: 01/11/2023]
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12
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Iglarz M, Binkert C, Morrison K, Fischli W, Gatfield J, Treiber A, Weller T, Bolli MH, Boss C, Buchmann S, Capeleto B, Hess P, Qiu C, Clozel M. Pharmacology of macitentan, an orally active tissue-targeting dual endothelin receptor antagonist. J Pharmacol Exp Ther 2008; 327:736-45. [PMID: 18780830 DOI: 10.1124/jpet.108.142976] [Citation(s) in RCA: 231] [Impact Index Per Article: 14.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
Macitentan, also called Actelion-1 or ACT-064992 [N-[5-(4-bromophenyl)-6-(2-(5-bromopyrimidin-2-yloxy)ethoxy)-pyrimidin-4-yl]-N'-propylaminosulfonamide], is a new dual ET(A)/ET(B) endothelin (ET) receptor antagonist designed for tissue targeting. Selection of macitentan was based on inhibitory potency on both ET receptors and optimization of physicochemical properties to achieve high affinity for lipophilic milieu. In vivo, macitentan is metabolized into a major and pharmacologically active metabolite, ACT-132577. Macitentan and its metabolite antagonized the specific binding of ET-1 on membranes of cells overexpressing ET(A) and ET(B) receptors and blunted ET-1-induced calcium mobilization in various natural cell lines, with inhibitory constants within the nanomolar range. In functional assays, macitentan and ACT-132577 inhibited ET-1-induced contractions in isolated endothelium-denuded rat aorta (ET(A) receptors) and sarafotoxin S6c-induced contractions in isolated rat trachea (ET(B) receptors). In rats with pulmonary hypertension, macitentan prevented both the increase of pulmonary pressure and the right ventricle hypertrophy, and it markedly improved survival. In diabetic rats, chronic administration of macitentan decreased blood pressure and proteinuria and prevented end-organ damage (renal vascular hypertrophy and structural injury). In conclusion, macitentan, by its tissue-targeting properties and dual antagonism of ET receptors, protects against end-organ damage in diabetes and improves survival in pulmonary hypertensive rats. This profile makes macitentan a new agent to treat cardiovascular disorders associated with chronic tissue ET system activation.
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Affiliation(s)
- Marc Iglarz
- Drug Discovery Department, Actelion Pharmaceuticals Ltd., Allschwil, Switzerland
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13
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Dai J, Lee CH, Poburko D, Szado T, Kuo KH, van Breemen C. Endothelin-1-mediated wave-like [Ca2+]i oscillations in intact rabbit inferior vena cava. J Vasc Res 2007; 44:495-503. [PMID: 17657165 DOI: 10.1159/000106553] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2007] [Accepted: 04/13/2007] [Indexed: 11/19/2022] Open
Abstract
Endothelin-1 (ET1) is an endogenous vasoconstrictor released by the vascular system to regulate the contractility of vascular smooth muscle cells (VSMC). It is implicated in the pathogenesis of hypertension and diabetic vasculopathy. In rabbit inferior vena cava (IVC), 10 nM ET1 induces tonic contraction mainly via type A endothelin receptor activation. Using confocal imaging of Fluo-3 loaded in thein situ VSMC within the intact IVC, we found that ET1 elicited [Ca2+]i oscillations with an average frequency of 0.31 +/- 0.01 Hz. These [Ca2+]i oscillations occurred as repetitive Ca2+ waves traveling along the longitudinal axis of the cells with an average velocity of 29 +/- 3 microm/s. The Ca2+ waves were not synchronized between neighboring VSMC nor were they propagated between them. Nifedipine (10 microM) inhibited the tonic contraction by 27.0 +/- 5.0% while SKF96365 (50 microM) abolished the remaining contraction. In a parallel Ca2+ study, nifedipine reduced the frequency of the oscillations to 0.22 +/- 0.01 Hz while SKF96365 abolished the remaining [Ca2+]i oscillations. Subsequent application of 25 mM caffeine elicited no further Ca2+ signal. Thus, we conclude that ET1 stimulates tonic contraction in the rabbit IVC by inducing [Ca2+]i oscillations and that stimulated Ca2+ entry through both the L-type voltage-gated Ca2+ channels and a nifedipine-resistant and SKF96365-sensitive pathway is crucial for the maintenance of [Ca2+]i oscillations and tonic contraction.
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MESH Headings
- Animals
- Calcium Channel Blockers/pharmacology
- Calcium Channels/drug effects
- Calcium Channels/metabolism
- Calcium Channels, L-Type/metabolism
- Calcium Signaling/drug effects
- Endothelin-1/metabolism
- Endothelin-1/pharmacology
- Female
- Imidazoles/pharmacology
- In Vitro Techniques
- Microscopy, Confocal
- Muscle, Smooth, Vascular/drug effects
- Muscle, Smooth, Vascular/metabolism
- Nifedipine/pharmacology
- Oligopeptides/pharmacology
- Peptides, Cyclic/pharmacology
- Piperidines/pharmacology
- Rabbits
- Receptor, Endothelin A/drug effects
- Receptor, Endothelin A/metabolism
- Time Factors
- Vasoconstriction/drug effects
- Vasoconstrictor Agents/metabolism
- Vasoconstrictor Agents/pharmacology
- Vena Cava, Inferior/metabolism
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Affiliation(s)
- Jiazhen Dai
- The James Hogg iCAPTURE Centre for Cardiovascular and Pulmonary Research, University of British Columbia, Vancouver, B.C., Canada
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14
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Clozel M, Flores S. Endothelin receptors as drug targets in chronic cardiovascular diseases: the rationale for dual antagonism. Drug Dev Res 2007. [DOI: 10.1002/ddr.20156] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
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15
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Schachner T. Pharmacologic inhibition of vein graft neointimal hyperplasia. J Thorac Cardiovasc Surg 2006; 131:1065-72. [PMID: 16678591 DOI: 10.1016/j.jtcvs.2005.11.043] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/09/2005] [Accepted: 11/16/2005] [Indexed: 11/25/2022]
Abstract
Although arterial conduits are widely used and have improved the long-term results of coronary artery bypass grafting, vein grafts remain important additional conduits in coronary surgery. Newer studies show a saphenous vein graft patency of 60% or more at 10 years postoperatively. The pathology of vein graft disease consists of thrombosis, neointimal hyperplasia, and vein graft atherosclerosis, which limit graft longevity. Therapeutic strategies to prevent vein graft disease include external stenting, pharmacotherapy, and gene therapy. The potential benefits of a pharmacologic approach are as follows: (1) Drugs with a broad clinical experience can be used; (2) side effects of systemic application can be minimized by local therapy; and (3) no vascular injury, such as pressurizing the vein for a viral transfection approach, is necessary. The different sites for pharmacotherapy in vein graft disease are reviewed in this article.
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Affiliation(s)
- Thomas Schachner
- Department of Cardiac Surgery, Innsbruck Medical University, Innsbruck, Austria.
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16
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Benza RL, Rayburn BK, Tallaj JA, Coffey CS, Pinderski LJ, Pamoukian SV, Bourge RC. Efficacy of Bosentan in a Small Cohort of Adult Patients With Pulmonary Arterial Hypertension Related to Congenital Heart Disease. Chest 2006; 129:1009-15. [PMID: 16608951 DOI: 10.1378/chest.129.4.1009] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/01/2022] Open
Abstract
OBJECTIVES This study was designed to assess the tolerability and efficacy of the oral endothelin receptor antagonist bosentan in adult patients with pulmonary arterial hypertension (PAH) related to congenital heart disease (CHD). BACKGROUND Severe PAH in the setting of CHD is a debilitating syndrome for which there are limited treatment options. This is the first long-term study experience in adults reporting on the tolerability and efficacy of therapy with bosentan for this patient population. METHODS A 12-month single-center experience with 19 women and 5 men with PAH associated with CHD (79% in New York Heart Association [NYHA] class III) was analyzed. Hemodynamic responses, exercise capacity, and Borg dyspnea index were assessed prior to the administration of bosentan, and again at 3, 6, and 12 months after the study began. Clinical assessments were performed monthly for up to 12 months. The change from baseline was tested using the Wilcoxon pairs test. RESULTS There was significant improvement in hemodynamics from baseline to 12 months (mean [+/- SD] systolic pulmonary arterial pressure, 99 +/- 30 to 87 +/- 28 mm Hg [p </= 0.001]; mean pulmonary arterial pressure, 60 +/- 18 to 52 +/- 17 mm Hg [p </= 0.001]; mean right atrial pressure, 12 +/- 6 to 8 +/- 5 mm Hg [p </= 0.001]; mean pulmonary vascular resistance, 663 +/- 386 to 504 +/- 307 dyne . s . cm(-5) [p < 0.01]; pulmonary capillary wedge pressure, 15 +/- 5 to 11 +/- 3 mm Hg [p < 0.001]). NYHA functional class also improved from baseline to 12 months (NYHA class I/II range, 17 to 71%; p < 0.001). There was a marginally significant trend toward improvement in the mean 6-min walk test distance at 12 months (299 +/- 85 to 330 +/- 95 m; p = 0.05). Three patients needed to discontinue bosentan therapy because of elevated liver function test results. There were no deaths or hospitalizations, and no significant change in arterial oxygen saturation had occurred at 12 months. CONCLUSIONS Bosentan therapy improved hemodynamics and NYHA class in patients with PAH that was associated with CHD. These effects were seen after 3 to 6 months. Bosentan therapy may provide an effective alternative to current therapies in this patient population.
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Affiliation(s)
- Raymond L Benza
- Tinsley Harrison Towers, Room 328A, 1900 University Blvd, Birmingham, AL 35294-0006, USA.
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17
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Fujimoto K, Ikenoya S. [Pharmacological characteristics and clinical efficacy of bosentan]. Nihon Yakurigaku Zasshi 2005; 126:407-18. [PMID: 16462092 DOI: 10.1254/fpj.126.407] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/06/2023]
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18
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Affiliation(s)
- Arshia Noori
- Fletcher Allen Health Care, University of Vermont, Burlington 05401, USA.
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19
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Sanmartín M, Fernández-Ortiz A, Fantidis P, Aragoncillo P, Fernández-Durango R, Rollín R, Alfonso F, Hernández R, Escaned J, Macaya C. Effects of bosentan on neointimal response following coronary angioplasty. Eur J Clin Invest 2003; 33:762-8. [PMID: 12925035 DOI: 10.1046/j.1365-2362.2003.01217.x] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
BACKGROUND Endothelins are important vasoconstrictors and cellular-growth promoters. ETA-specific antagonists have been shown to reduce neointimal response to injury in some experimental angioplasty models. However, there is little information on the effects of dual ETA/ETB receptor blockers, such as bosentan, on neointimal proliferation following experimental coronary angioplasty. MATERIALS AND METHODS Coronary injury was achieved by directional atherectomy in the left anterior descending artery of 20 pigs. Animals were randomly assigned to receive a daily dose of oral bosentan (30 mg kg-1) (group I, n = 10) or no treatment (group II, n = 10). At 4 weeks, arteries were processed for histomorphometry and endothelin characterization. RESULTS Vessel injury score was similar among the two groups. Overall, a linear correlation was found between injury and neointimal development (r = 0.57, P = 0.01). This correlation had a lower slope in group I compared with group II (P < 0.001), indicating a smaller amount of neointimal development for a similar degree of injury in bosentan-treated animals. Multivariate regression showed that neointimal response was reduced by oral treatment with bosentan (beta: -0.59 mm2, 95% CI: -1.11/-0.06 mm2). In addition, immunostaining revealed fewer positive endothelin areas in group I arteries. CONCLUSIONS Oral treatment with bosentan reduces neointimal development following coronary angioplasty in this experimental model.
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Affiliation(s)
- M Sanmartín
- Cardiovascular Institute, San Carlos University Hospital, Madrid, Spain.
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20
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Clozel M. Effects of bosentan on cellular processes involved in pulmonary arterial hypertension: do they explain the long-term benefit? Ann Med 2003; 35:605-13. [PMID: 14708970 DOI: 10.1080/07853890310017477] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/26/2022] Open
Abstract
Pulmonary arterial hypertension is a rapidly progressing disease characterized by an over- expression of endothelin. In addition to its potent pulmonary vasoconstrictor effects, endothelin has been shown to produce many of the aberrant changes, such as hypertrophy, fibrosis, inflammation, and neurohormonal activation that underlie the shortened life span in pulmonary arterial hypertensive patients. The fact that endothelin expression correlates significantly with disease severity and outcome in these patients suggests that endothelin, through binding to both ETA and ETB receptor subtypes, is a key causative agent in the pathophysiology of pulmonary arterial hypertension. The orally active dual endothelin receptor antagonist bosentan competitively antagonizes the binding of endothelin to both endothelin receptor subtypes with high affinity and specificity. In animal models relevant for the pathophysiology of pulmonary hypertension, bosentan not only causes selective pulmonary vasodilation, but also prevents vascular hypertrophy and cardiac remodeling, attenuates pulmonary fibrosis, decreases vascular inflammation, and blunts neurohormonal activation. These experimental data may explain the effects on disease progression and the long-term benefit observed with bosentan in pulmonary arterial hypertension.
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Affiliation(s)
- Martine Clozel
- Actelion Pharmaceuticals Ltd, Innovation Centre, Gewerbestrasse 16, Allschwil, CH-4123 Switzerland.
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21
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Uddman E, Adner M, Edvinsson L. Protein kinase C inhibitors decrease endothelin ET(B) receptor mRNA expression and contraction during organ culture of rat mesenteric artery. Eur J Pharmacol 2002; 452:215-22. [PMID: 12354572 DOI: 10.1016/s0014-2999(02)02303-8] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
The effect of protein kinase C (PKC) inhibitors on the induction of endothelin ET(B) receptors during organ culture was examined in isolated segments of the rat mesenteric artery. After 24 h of organ culture, the endothelin ET(B) receptor agonist sarafotoxin 6c (S6c) induced a strong contraction compared to fresh segments. The contractile response after 24-h organ culture to S6c was studied in presence (30-min preincubation) or absence, after 24-h treatment, of the PKC inhibitors staurosporine, K252a and Ro31-7549. Exposure to staurosporine or K252a in presence and after 24-h treatment reduced the S6c contraction. In contrast, presence of 2-1[1-3(aminopropyl)indol-3-yl]-3(1-methyl-1H-indol-3-yl)maleimide (Ro31-7549), did not affect the S6c-induced contraction, whereas 24-h treatment abolished the increase of contraction. The PKA inhibitor N-(2-[bromocinnamylamino]-ethyl)-5-isoquinolinesulfonamide (H89) did not affect the S6c responses. The mRNA expressions of endothelin ET(B) receptors (analysed with real-time PCR) were abolished after 24-h treatment with the PKC inhibitors. These results suggest that PKC is involved in the endothelin ET(B) receptor upregulation following organ culture.
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Affiliation(s)
- Erik Uddman
- Department of Internal Medicine, Lund University Hospital, Lund, Sweden.
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22
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D'Orléans-Juste P, Labonté J, Bkaily G, Choufani S, Plante M, Honoré JC. Function of the endothelinB receptor in cardiovascular physiology and pathophysiology. Pharmacol Ther 2002; 95:221-38. [PMID: 12243796 DOI: 10.1016/s0163-7258(02)00235-8] [Citation(s) in RCA: 111] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
One of the two receptors by which the potent vasoactive effects of endothelin (ET)-1 are mediated is the ET(B) receptor (ET(BR)), which is found in several tissues, but, more importantly from a cardiovascular point of view, on the endothelial cell. The endothelial cell also has the unique capability of releasing ET-1, as well as other factors, such as the endothelial-derived relaxing factors and prostacyclin, which counteract the myotropic effects of the peptide. The secretory and contractile responses to ET-1 rely on G-protein-coupled ET(BR)s, as well as ET(A)-G-protein-coupled receptor-like proteins. The mitogenic properties of ET-1 via ET(A) receptors (ET(AR)s) coupled to mitogen-activated protein kinases and tyrosine kinases on the vascular smooth muscle may occur in conjunction with the anti-apoptotic characteristics of the endothelial ET(BR)s. Interestingly, most of the relevant antagonists and agonists for both ET(AR)s and ET(BR)s have been developed by the pharmaceutical industry. This highlights the therapeutical potential of compounds that act on ET receptors. In normal as well as in physiopathological conditions, the ET(BR) plays an important role in the control of vascular tone, and must be taken into account when using ET receptor antagonists for the treatment of cardiovascular diseases. For the management of congestive heart failure, renal failure and primary pulmonary hypertension, the most recent literature supports the use of selective ET(AR) antagonists rather than mixed antagonists of ET(AR)s and ET(BR)s. Nonetheless, validation of this view will have to await the first clinical trials comparing the actions of ET(A) to mixed ET(A)/ET(B) receptor antagonists.
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Affiliation(s)
- P D'Orléans-Juste
- Department of Pharmacology, Institut de Pharmacologie de Sherbrooke, Medical School, Université de Sherbrooke, 3001 12th Avenue North, Sherbrooke, J1H 5N4, Québec, Canada.
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23
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Okada M, Nishikibe M. BQ-788, a selective endothelin ET(B) receptor antagonist. CARDIOVASCULAR DRUG REVIEWS 2002; 20:53-66. [PMID: 12070534 DOI: 10.1111/j.1527-3466.2002.tb00082.x] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
We describe characteristics of a selective endothelin (ET) ET(B) receptor antagonist, BQ-788 [N-cis-2,6-dimethylpiperidinocarbonyl-L-gamma-methylleucyl-D-1-methoxycarbonyltryptophanyl-D-norleucine], which is widely used to demonstrate the role of endogenous or exogenous ETs in vitro and in vivo. In vitro, BQ-788 potently and competitively inhibited (125)I-labeled ET-1 binding to ET(B) receptors in human Girrardi heart cells (hGH) with an IC(50) of 1.2 nM, but only poorly inhibited the binding to ET A receptors in human neuroblastoma cell line SK-N-MC cells (IC(50), 1300 nM). In isolated rabbit pulmonary arteries, BQ-788 showed no agonistic activity up to 10 microM and competitively inhibited the vasoconstriction induced by an ET(B)-selective agonist (pA(2), 8.4). BQ-788 also inhibited several bioactivities of ET-1, such as bronchoconstriction, cell proliferation, and clearance of perfused ET-1. Thus, it is confirmed that BQ-788 is a potent, selective ET(B) receptor antagonist. In vivo, in conscious rats, BQ-788, 3 mg/kg/h, i.v., completely inhibited a pharmacological dose of ET-1- or sarafotoxin6c (S6c) (0.5 nmol/kg, i.v.)-induced ET(B) receptor-mediated depressor, but not pressor responses. Furthermore, BQ-788 markedly increased the plasma concentration of ET-1, which is considered an index of potential ET(B) receptor blockade in vivo. In Dahl salt-sensitive hypertensive (DS) rats, BQ-788, 3 mg/kg/h, i.v., increased blood pressure by about 20 mm Hg. It is reported that BQ-788 also inhibited ET-1-induced bronchoconstriction, tumor growth and lipopolysaccharide-induced organ failure. These data suggest that BQ-788 is a good tool for demonstrating the role of ET-1 and ET(B) receptor subtypes in physiological and/or pathophysiological conditions.
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Affiliation(s)
- Megumu Okada
- Pharmacology, Tsukuba Research Institute, Banyu Pharmaceutical Co., Ltd., Tsukuba, Ibaraki 300-2611, Japan.
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24
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Porter KE, Dickinson T, London NJ. Inhibition of neointima formation in an organ culture of human saphenous vein: a comparison of dual endothelin-converting enzyme/neutral endopeptidase and selective neutral endopeptidase inhibition. J Vasc Surg 2001; 34:548-54. [PMID: 11533610 DOI: 10.1067/mva.2001.115960] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
PURPOSE Endothelin-1 (ET-1) has been implicated in a variety of vascular pathologic conditions, although there is considerable controversy as to whether such effects are mediated by the ET-(A) or ET-(B) receptor. This study investigated whether inhibition of big ET-1 processing by inhibition of endothelin-converting enzyme (ECE) could, therefore, offer an alternative therapeutic strategy in the prevention of vein graft intimal hyperplasia. METHODS Human saphenous vein (3 equal segments from 10 patients) were maintained in organ culture for 14 days with either 50 micromol/L CGS 26303 (a dual ECE/neutral endopeptidase [NEP] inhibitor), 50 micromol/L CGS 24592 (a selective NEP inhibitor), or vehicle (control). They were then processed for immunostaining and neointimal thickness measurements, and conditioned media was collected for enzyme-linked immunosorbent assay analysis. RESULTS Neointimal thickness in the ECE/NEP-inhibited veins did not differ significantly from that of control segments. However, there was a highly significant augmentation in the NEP-inhibited segments, consistent with an inhibition of ET-1 degradation (median difference, 16.8; 95% CI, -23.5, -10.4; P =.002, Wilcoxon). ECE immunostaining was reduced in the ECE/NEP-inhibited veins, although ET-1 staining was also present. ET-1 expression was intense in the thickened neointimas of NEP-inhibited veins, which also showed significant ECE staining. Elevated levels of big ET-1 were measured in the ECE/NEP-inhibited veins, consistent with reduced ECE activity. However, mature ET-1 was still detectable in these segments. CONCLUSION There is a requirement for potent and selective inhibitors of ECE to evaluate fully the potential therapeutic benefits of blocking ET-1 biosynthesis. The use of dual inhibitors complicates the interpretation of results, because the observed response is likely to be a combination of both ECE and NEP inhibition.
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Affiliation(s)
- K E Porter
- Department of Surgery, Robert Kilpatrick Clinical Sciences Building, Leicester University, Leicester Royal Infirmary, United Kingdom
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25
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Weiss MF, Scivittaro V, Anderson JM. Oxidative stress and increased expression of growth factors in lesions of failed hemodialysis access. Am J Kidney Dis 2001; 37:970-80. [PMID: 11325679 DOI: 10.1016/s0272-6386(05)80013-7] [Citation(s) in RCA: 146] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
The pathological role of oxidative stress in patients treated by hemodialysis has gained increasing recognition in recent years. Because complications related to vascular access are a major source of morbidity, immunohistochemical evidence of oxidative stress and activation of growth factors were examined in native arteriovenous (AV) fistulae (n = 11) and expanded polytetrafluoroethylene (ePTFE) grafts (n = 15) recovered from hemodialysis patients at the time of surgical revision or resection. To show the presence of oxidative stress in tissues, three markers were chosen: N(epsilon)(carboxymethyl)lysine, a structurally identified advanced glycation end product; 4-hydroxy-2,3-nonenol, a lipid peroxidation product; and redox-active transition metals bound to proteins, a source of Fenton chemistry-generated free radicals. Markers of cell growth and proliferation were endothelin-1 (ET-1), a potent mitogenic peptide implicated in the formation of intimal hyperplasia; transforming growth factor-beta (TGF-beta), a stimulus to vascular cell growth and matrix production; and platelet-derived growth factor (PDGF), a mediator of intimal hyperplasia. All specimens studied showed significant intimal hyperplasia. In general, the neointima close to the vascular lumen of the AV fistula and the pseudointima close to the lumen of the ePTFE graft were positive for oxidative stress markers. At sites of injury, especially in the presence of histological evidence of inflammation and healing, expression of oxidative markers was particularly intense. Prominent staining of PDGF was shown at sites of anastomotic hyperplasia and in neovasculature. TGF-beta was associated with proliferation or repair in both AV fistulae and ePTFE grafts. ET-1 staining was most intense in the neointima and pseudointima. This study showed histochemical colocalization of markers of oxidative stress with growth factors known to contribute to intimal hyperplasia.
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Affiliation(s)
- M F Weiss
- Department of Medicine, Division of Nephrology, University Hospitals of Cleveland, OH 44106, USA.
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26
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Abstract
Saphenous vein graft stenosis is a significant clinical complication for coronary artery bypass patients. Endothelin-1, a peptide synthesised by vascular endothelial cells, is the most potent known vasoconstrictor and has mitogenic properties. Recent advances in our knowledge of endothelin-1 synthesis and endothelin receptor expression and function in normal and atherosclerotic human saphenous vein imply a role for the peptide in the progression of vein graft failure. Manipulation of the endothelin system, by selective receptor antagonism or inhibition of the specific endothelin-converting enzymes may, therefore, represent a novel therapeutic target for treating vein graft disease.
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MESH Headings
- Animals
- Aspartic Acid Endopeptidases/antagonists & inhibitors
- Aspartic Acid Endopeptidases/genetics
- Aspartic Acid Endopeptidases/metabolism
- Coronary Artery Bypass/adverse effects
- Endothelin Receptor Antagonists
- Endothelin-Converting Enzymes
- Endothelins/genetics
- Endothelins/metabolism
- Endothelins/physiology
- Endothelium, Vascular/metabolism
- Endothelium, Vascular/pathology
- Graft Occlusion, Vascular/etiology
- Graft Occlusion, Vascular/metabolism
- Graft Occlusion, Vascular/pathology
- Humans
- Hyperplasia
- Metalloendopeptidases
- Muscle, Smooth, Vascular/metabolism
- Muscle, Smooth, Vascular/pathology
- Receptors, Endothelin/genetics
- Receptors, Endothelin/metabolism
- Saphenous Vein/transplantation
- Tunica Intima/pathology
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Affiliation(s)
- A P Davenport
- Clinical Pharmacology Unit, University of Cambridge, Centre for Clinical Investigation, Addenbrooke's Hospital, Cambridge, UK.
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27
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Lauth M, Cattaruzza M, Hecker M. ACE inhibitor and AT1 antagonist blockade of deformation-induced gene expression in the rabbit jugular vein through B2 receptor activation. Arterioscler Thromb Vasc Biol 2001; 21:61-6. [PMID: 11145934 DOI: 10.1161/01.atv.21.1.61] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Deformation-induced endothelin-1 synthesis in endothelial cells may contribute to the intimal hyperplasia of venous bypass grafts. ACE inhibitors and angiotensin II type 1 (AT(1)) receptor antagonists are capable of reducing vein graft disease. Therefore, the effects of these drugs on endothelial preproendothelin-1 (ppET-1) and smooth muscle endothelin B receptor (ET(B)-R) expression were investigated in isolated perfused segments of the rabbit jugular vein. Pretreatment with ramiprilat (0.3 micromol/L) or irbesartan (0.01 to 1 micromol/L) had no effect on basal ppET-1 or ET(B)-R expression but markedly attenuated the deformation-induced expression of these gene products, and these effects were reversed by the B(2) receptor antagonist icatibant (Hoe 140) and by the NO synthase inhibitor N(G)-nitro-L-arginine. Candesartan (1 micromol/L) mimicked the inhibitory effect of irbesartan. Moreover, reporter gene analysis with a rat ppET-1 promoter-luciferase construct transiently transfected into porcine aortic cultured endothelial cells revealed that the inhibitory effect of both ramiprilat and irbesartan on deformation-induced ppET-1 expression is species independent and mediated at the level of transcription. In addition, RT-PCR analysis detected only AT(1) receptor expression in the endothelium-intact rabbit jugular vein, and neither irbesartan nor ramiprilat affected endothelial NO synthase expression. Thus, ACE inhibitors and AT(1) receptor antagonists are capable of suppressing deformation-induced gene expression in the vessel wall in both an autocrine (ppET-1) and a paracrine (ET(B)-R) manner via a common mechanism of action that constitutes a B(2) receptor-mediated increase in endothelial NO release.
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MESH Headings
- Angiotensin Receptor Antagonists
- Angiotensin-Converting Enzyme Inhibitors/pharmacology
- Animals
- Biphenyl Compounds/pharmacology
- Cells, Cultured
- Endothelin-1/biosynthesis
- Endothelin-1/genetics
- Endothelin-1/metabolism
- Gene Expression Regulation/drug effects
- Glyceraldehyde-3-Phosphate Dehydrogenases/pharmacology
- In Vitro Techniques
- Irbesartan
- Male
- Peptide Fragments/pharmacology
- Perfusion
- Pressure
- RNA, Messenger/biosynthesis
- Rabbits
- Ramipril/analogs & derivatives
- Ramipril/pharmacology
- Receptor, Angiotensin, Type 1
- Receptor, Angiotensin, Type 2
- Receptor, Bradykinin B2
- Receptor, Endothelin B
- Receptors, Angiotensin/metabolism
- Receptors, Bradykinin/metabolism
- Receptors, Endothelin/biosynthesis
- Receptors, Endothelin/genetics
- Receptors, Endothelin/metabolism
- Swine
- Tetrazoles/pharmacology
- Transfection
- Vasoconstriction/drug effects
- Vasoconstriction/genetics
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Affiliation(s)
- M Lauth
- Department of Cardiovascular Physiology, University of Göttingen, Göttingen, Germany
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28
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Wagner AH, Krzesz R, Gao D, Schroeder C, Cattaruzza M, Hecker M. Decoy oligodeoxynucleotide characterization of transcription factors controlling endothelin-B receptor expression in vascular smooth muscle cells. Mol Pharmacol 2000; 58:1333-40. [PMID: 11093771 DOI: 10.1124/mol.58.6.1333] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Endothelin-1 is not only a powerful vasoconstrictor but also a potent mitogen for vascular smooth muscle cells (SMC), acting through both the endothelin-A and endothelin-B receptor (ET(B)-R). Although vascular SMC are known to express the ET(B)-R, its transcriptional regulation has not been studied thus far. Here we demonstrate that the potent inhibitor of nuclear factor kappaB activation, pyrrolidine dithiocarbamate (PDTC; 30-100 microM), induces de novo ET(B)-R expression in rat aortic and mesenteric cultured SMC. Electrophoretic mobility shift analyses revealed that besides inhibition of nuclear factor kappaB, PDTC enhances activator protein-1 (AP-1), CCAAT/enhancer-binding protein (C/EBP), and GATA-2 activity in these cells. Preincubation of PDTC-stimulated cells with appropriate decoy oligodeoxynucleotides confirmed the involvement of these three transcription factors, namely that of AP-1, in ET(B)-R expression. The stimulatory effect of PDTC on ET(B)-R expression was also confirmed functionally by monitoring an enhanced ET-1-induced apoptosis in PDTC-treated cells that was sensitive to the ET(B)-R antagonist, BQ788. Taken together, these findings demonstrate that C/EBP, GATA-2, and in particular AP-1 can control ET(B)-R expression in vascular SMC. They further support the notion that ET(B)-R expression in these cells may play an important role in cardiovascular complications, such as restenosis following angioplasty that in the early phase is characterized by prominent SMC apoptosis.
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Affiliation(s)
- A H Wagner
- Department of Cardiovascular Physiology, University of Goettingen, Germany
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29
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Lauth M, Berger MM, Cattaruzza M, Hecker M. Pressure-induced upregulation of preproendothelin-1 and endothelin B receptor expression in rabbit jugular vein in situ : implications for vein graft failure? Arterioscler Thromb Vasc Biol 2000; 20:96-103. [PMID: 10634805 DOI: 10.1161/01.atv.20.1.96] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Upregulation of endothelin-1 (ET-1) synthesis in venous bypass grafts in response to arterial levels of blood pressure may play a major role in graft failure. To investigate this hypothesis, isolated segments of the rabbit jugular vein were perfused at physiological (0 to 5 mm Hg) and nonphysiological (20 mm Hg) levels of intraluminal pressure. As judged by reverse transcription-polymerase chain reaction analysis (mRNA level), neither endothelin-converting enzyme nor endothelin A receptor expression appeared to be pressure sensitive. In contrast, there was a profound and time-dependent increase in endothelial prepro-ET-1 mRNA and intravascular ET-1 abundance (by ELISA) as well as in smooth muscle endothelin B receptor mRNA and functional protein (by superfusion bioassay) on raising the perfusion pressure from 5 to 20 mm Hg, but not from 0 to 5 mm Hg, for up to 12 hours. Video microscopy analysis revealed that the segments were distended by 75% at 5 mm Hg and near maximally at 20 mm Hg compared with the resting diameter at 0 to 1 mm Hg. Treatment of the segments with actinomycin D (1 micromol/L), the specific protein kinase C inhibitor, Ro 31-8220 (0.1 micromol/L), or the c-Src family-specific tyrosine kinase inhibitor, herbimycin A (0.1 micromol/L), demonstrated that the pressure-induced expression of these gene products occurs at the level of transcription and requires activation of protein kinase C, but not c-Src. In venous bypass grafts such deformation-induced changes in gene expression may contribute not only to acute graft failure through ET-1-induced vasospasm but also to endothelin A receptor- and/or endothelin B receptor-mediated smooth muscle cell hyperplasia and graft occlusion.
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Affiliation(s)
- M Lauth
- Department of Cardiovascular Physiology, University of Goettingen, Goettingen, Germany
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