151
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Dronadula N, Rizvi F, Blaskova E, Li Q, Rao GN. Involvement of cAMP-response element binding protein-1 in arachidonic acid-induced vascular smooth muscle cell motility. J Lipid Res 2005; 47:767-77. [PMID: 16382163 DOI: 10.1194/jlr.m500369-jlr200] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
In addition to their role in many vital cellular functions, arachidonic acid (AA) and its eicosanoid metabolites are involved in the pathogenesis of several diseases, including atherosclerosis and cancer. To understand the potential mechanisms by which these lipid molecules could influence the disease processes, particularly cardiovascular diseases, we studied AA's effects on vascular smooth muscle cell (VSMC) motility and the role of cAMP-response element binding protein-1 (CREB-1) in this process. AA exerted differential effects on VSMC motility; at lower doses, it stimulated motility, whereas at higher doses, it was inhibitory. AA-induced VSMC motility requires its conversion via the lipoxygenase (LOX) and cyclooxygenase (COX) pathways. AA stimulated the phosphorylation of extracellular signal-regulated kinases (ERKs), Jun N-terminal kinases (JNKs), and p38 mitogen-activated protein kinase (p38MAPK) in a time-dependent manner, and blockade of these serine/threonine kinases significantly attenuated AA-induced VSMC motility. In addition, AA stimulated CREB-1 phosphorylation and activity in a manner that was also dependent on its metabolic conversion via the LOX and COX pathways and the activation of ERKs and p38MAPK but not JNKs. Furthermore, suppression of CREB-1 activation inhibited AA-induced VSMC motility. 15(S)-Hydroxyeicosatetraenoic acid and prostaglandin F2alpha, the 15-LOX and COX metabolites of AA, respectively, that are produced by VSMC at lower doses, were also found to stimulate motility in these cells. Together, these results suggest that AA induces VSMC motility by complex mechanisms involving its metabolism via the LOX and COX pathways as well as the ERK- and p38MAPK-dependent and JNK-independent activation of CREB-1.
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MESH Headings
- Animals
- Arachidonic Acid/metabolism
- Arachidonic Acid/pharmacology
- Cell Movement/drug effects
- Cell Movement/physiology
- Cells, Cultured
- Cyclic AMP Response Element-Binding Protein/genetics
- Cyclic AMP Response Element-Binding Protein/metabolism
- Cytochrome P-450 Enzyme System/metabolism
- Dinoprost/metabolism
- Extracellular Signal-Regulated MAP Kinases/metabolism
- Genes, Reporter
- Hydroxyeicosatetraenoic Acids/metabolism
- JNK Mitogen-Activated Protein Kinases/metabolism
- Lipoxygenase/metabolism
- Male
- Muscle, Smooth, Vascular/cytology
- Muscle, Smooth, Vascular/drug effects
- Myocytes, Smooth Muscle/cytology
- Myocytes, Smooth Muscle/drug effects
- Myocytes, Smooth Muscle/metabolism
- Prostaglandin-Endoperoxide Synthases/metabolism
- Rats
- Rats, Sprague-Dawley
- Signal Transduction/physiology
- p38 Mitogen-Activated Protein Kinases/metabolism
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Affiliation(s)
- Nagadhara Dronadula
- Department of Physiology, University of Tennessee Health Science Center, Memphis, TN 38163, USA
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152
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Babaev VR, Ding L, Reese J, Morrow JD, Breyer MD, Dey SK, Fazio S, Linton MF. Cyclooxygenase-1 deficiency in bone marrow cells increases early atherosclerosis in apolipoprotein E- and low-density lipoprotein receptor-null mice. Circulation 2005; 113:108-17. [PMID: 16380543 DOI: 10.1161/circulationaha.105.591537] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
BACKGROUND Cyclooxygenase-1 (COX-1) has been implicated in the pathogenesis of atherothrombosis and is expressed by the major cell types of atherosclerotic lesions. COX-1-mediated platelet thromboxane (TX) production has been proposed to promote both early atherosclerosis and thrombosis. Here, we examined the impact of COX-1 deficiency in bone marrow-derived cells on early atherogenesis in the mouse. METHODS AND RESULTS LDL receptor (LDLR)(-/-) and apolipoprotein E (apoE)(-/-) recipient mice were lethally irradiated and transplanted with COX-1(-/-) bone marrow. Mice reconstituted with COX-1(-/-) marrow had nearly complete (99.7%) loss of platelet TXA2 and significantly suppressed levels of macrophage and urinary TXA2 metabolites. Serum lipid levels and lipoprotein distributions did not differ between recipients reconstituted with COX-1(+/+) and COX-1(-/-) marrow. Surprisingly, the extent of atherosclerotic lesions in both LDLR(-/-) and apoE(-/-) mice reconstituted with COX-1(-/-) marrow was increased significantly compared with control mice transplanted with COX-1(+/+) marrow. Peritoneal macrophages isolated from LDLR(-/-) mice reconstituted with COX-1(-/-) marrow had increased lipopolysaccharide-induced levels of COX-2 mRNA and protein expression. Fetal liver cell transplantation studies revealed a 30% increase in atherosclerosis in COX-1(-/-)-->LDLR(-/-)mice compared with COX-1(+/+)-->LDLR(-/-)mice, whereas the extent of atherosclerosis was unchanged in COX-1(-/-)/COX-2(-/-)-->LDLR(-/-)mice. CONCLUSIONS COX-1 deficiency in bone marrow-derived cells worsens early atherosclerosis in apoE(-/-) and LDLR(-/-) mice despite virtual elimination of platelet TX production. These data demonstrate that platelet TX production does not aggravate early atherosclerotic lesion formation and that upregulation of COX-2 expression in COX-1(-/-) macrophages is proatherogenic.
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Affiliation(s)
- Vladimir R Babaev
- Department of Medicine, Vanderbilt University Medical Center, Nashville, TN, USA.
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153
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Abstract
Atherosclerotic plaque rupture is promoted by metalloproteinase (MMP)-2 and MMP-9, enzymes that degrade the fibrous cap leading to plaque erosion. MMP biosynthesis is mediated by prostaglandin (PG)E2, the product of cyclooxygenase (COX)-2/inducible PGE synthase (mPGES) activity. We have recently reported the overexpression of COX-2/mPGES-1 in vulnerable plaques as a basis of MMP-mediated plaque instability. Hypercholesterolemia and hypertension are two important risk factors for atherosclerosis. Recent trial showed that statins and AT1 receptor blockers significantly reduce the incidence of cardiovascular events in humans. Since anti-inflammatory effects have been reported in association to therapy with statins or AT1 receptor blockers, in two different studies we hypothesized that these drugs can stabilize atherosclerotic plaques through modulation of COX-2/mPGES-1-dependent MMP biosynthesis. Our data demonstrated the stabilizing effect of atherosclerotic plaques by simvastatin or irbesartan, that is due, at least in part, to the reduction of inflammatory burden and suppression of PGE2-dependent metalloproteinases release.
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Affiliation(s)
- A Mezzetti
- Atherosclerosis Prevention Center, G d'Annunzio University of Chieti, Chieti, Italy.
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154
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Pavlovic S, Du B, Sakamoto K, Khan KMF, Natarajan C, Breyer RM, Dannenberg AJ, Falcone DJ. Targeting prostaglandin E2 receptors as an alternative strategy to block cyclooxygenase-2-dependent extracellular matrix-induced matrix metalloproteinase-9 expression by macrophages. J Biol Chem 2005; 281:3321-8. [PMID: 16338931 DOI: 10.1074/jbc.m506846200] [Citation(s) in RCA: 81] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
COX-2-dependent prostaglandin (PG) E2 synthesis regulates macrophage MMP expression, which is thought to destabilize atherosclerotic plaques. However, the administration of selective COX-2 inhibitors paradoxically increases the frequency of adverse cardiovascular events potentially through the loss of anti-inflammatory prostanoids and/or disturbance in the balance of pro- and anti-thrombotic prostanoids. To avoid these collateral effects of COX-2 inhibition, a strategy to identify and block specific prostanoid-receptor interactions may be required. We previously reported that macrophage engagement of vascular extracellular matrix (ECM) triggers proteinase expression through a MAPKerk1/2-dependent increase in COX-2 expression and PGE2 synthesis. Here we demonstrate that elicited macrophages express the PGE2 receptors EP1-4. When plated on ECM, their expression of EP2 and EP4, receptors linked to PGE2-induced activation of adenylyl cyclase, is strongly stimulated. Forskolin and dibutryl cyclic-AMP stimulate macrophage matrix metalloproteinase (MMP)-9 expression in a dose-dependent manner. However, an EP2 agonist (butaprost) has no effect on MMP-9 expression, and macrophages from EP2 null mice exhibited enhanced COX-2 and MMP-9 expression when plated on ECM. In contrast, the EP4 agonist (PGE1-OH) stimulated macrophage MMP-9 expression, which was inhibited by the EP4 antagonist ONO-AE3-208. When compared with COX-2 silencing by small interfering RNA or inhibition by celecoxib, the EP4 antagonist was as effective in inhibiting ECM-induced proteinase expression. In addition, ECM-induced MMP-9 expression was blocked in macrophages in which EP4 was silenced by small interfering RNA. Thus, COX-2-dependent ECM-induced proteinase expression is effectively blocked by selective inhibition of EP4, a member of the PGE2 family of receptors.
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Affiliation(s)
- Svetlana Pavlovic
- Department of Pathology and Laboratory Medicine, Vascular Biology Center, Joan and Sanford I. Weill Medical College of Cornell University, New York, New York 10021, USA
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155
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Federici M, Hribal ML, Menghini R, Kanno H, Marchetti V, Porzio O, Sunnarborg SW, Rizza S, Serino M, Cunsolo V, Lauro D, Mauriello A, Smookler DS, Sbraccia P, Sesti G, Lee DC, Khokha R, Accili D, Lauro R. Timp3 deficiency in insulin receptor-haploinsufficient mice promotes diabetes and vascular inflammation via increased TNF-alpha. J Clin Invest 2005; 115:3494-505. [PMID: 16294222 PMCID: PMC1283942 DOI: 10.1172/jci26052] [Citation(s) in RCA: 132] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2005] [Accepted: 09/26/2005] [Indexed: 11/17/2022] Open
Abstract
Activation of inflammatory pathways may contribute to the beginning and the progression of both atherosclerosis and type 2 diabetes. Here we report a novel interaction between insulin action and control of inflammation, resulting in glucose intolerance and vascular inflammation and amenable to therapeutic modulation. In insulin receptor heterozygous (Insr+/-) mice, we identified the deficiency of tissue inhibitor of metalloproteinase 3 (Timp3, an inhibitor of both TNF-alpha-converting enzyme [TACE] and MMPs) as a common bond between glucose intolerance and vascular inflammation. Among Insr+/- mice, those that develop diabetes have reduced Timp3 and increased TACE activity. Unchecked TACE activity causes an increase in levels of soluble TNF-alpha, which subsequently promotes diabetes and vascular inflammation. Double heterozygous Insr+/-Timp3+/- mice develop mild hyperglycemia and hyperinsulinemia at 3 months and overt glucose intolerance and hyperinsulinemia at 6 months. A therapeutic role for Timp3/TACE modulation is supported by the observation that pharmacological inhibition of TACE led to marked reduction of hyperglycemia and vascular inflammation in Insr+/- diabetic mice, as well as by the observation of increased insulin sensitivity in Tace+/- mice compared with WT mice. Our results suggest that an interplay between reduced insulin action and unchecked TACE activity promotes diabetes and vascular inflammation.
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Affiliation(s)
- Massimo Federici
- Center for Atherosclerosis, Policlinico Tor Vergata University Hospital, Rome, Italy.
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156
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Dogné JM, Hanson J, Pratico D. Thromboxane, prostacyclin and isoprostanes: therapeutic targets in atherogenesis. Trends Pharmacol Sci 2005; 26:639-44. [PMID: 16243403 DOI: 10.1016/j.tips.2005.10.001] [Citation(s) in RCA: 75] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2005] [Revised: 08/22/2005] [Accepted: 10/06/2005] [Indexed: 01/18/2023]
Abstract
Atherosclerosis is a chronic disease of the vasculature that is influenced by multiple factors that involve a complex interplay between some components of the blood and the arterial wall. Inflammation and oxidative stress have key roles in atherogenesis. The production of F2-isoprostanes (F2-IPs), thromboxane A2 (TxA2) and prostacyclin (PGI2) increases in atherosclerosis, and recent studies show that pharmacological modulation of their biosynthesis and biological activities are important therapeutic targets for managing atherosclerosis. In this review, we highlight recent breakthroughs in the roles of F2-IPs, TxA2 and PGI2 in atherogenesis, and identify pertinent therapeutic targets.
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Affiliation(s)
- Jean-Michel Dogné
- Department of Pharmacy, University of Namur, rue de Bruxelles 61, B-5000 Namur, Belgium.
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157
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Gómez-Hernández A, Martín-Ventura JL, Sánchez-Galán E, Vidal C, Ortego M, Blanco-Colio LM, Ortega L, Tuñón J, Egido J. Overexpression of COX-2, Prostaglandin E synthase-1 and prostaglandin E receptors in blood mononuclear cells and plaque of patients with carotid atherosclerosis: regulation by nuclear factor-kappaB. Atherosclerosis 2005; 187:139-49. [PMID: 16212965 DOI: 10.1016/j.atherosclerosis.2005.08.035] [Citation(s) in RCA: 73] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/07/2005] [Revised: 06/28/2005] [Accepted: 08/24/2005] [Indexed: 12/12/2022]
Abstract
BACKGROUND AND OBJECTIVE Prostaglandin E2 (PGE(2), a product of the cyclooxygenase 2 (COX-2) and membrane-associated Prostaglandin E Synthase (mPGES-1) pathway, has been implicated in the instability of atherosclerotic plaques. We have studied COX-2, mPGES-1 and PGE2 receptors (EPs) expression in peripheral blood mononuclear cells (PBMC) and atherosclerotic plaques of 29 patients with carotid stenosis as well as the effect of different nuclear factor-kappaB (NF-kappaB) inhibitors on COX-2, mPGES-1 and EPs expression in cultured monocytic cells (THP-1). METHODS COX-2, mPGES-1 and EP expression was analyzed by RT-PCR (PBMC), immunohistochemistry (plaques) and Western blot (THP-1). PGE2 levels were determined by ELISA (plasma and cell supernatants). RESULTS In relation to healthy controls, COX-2, mPGES-1 and EP-3/EP-4 mRNA expression was increased in PBMC from patients. In the inflammatory region of atherosclerotic plaques, an increase of COX-2, mPGES-1 and EPs expression was also observed. Activated NF-kappaB and COX-2, mPGES-1 and EPs proteins were colocalized in the plaque's cells. In cytokine-treated cultured THP-1, the NF-kappaB inhibitors parthenolide, Bay 11-7082 and PDTC reduced COX-2, mPGES-1 and EP-1/EP-3/EP-4 expression as well as PGE2 levels. By employing specific agonists and antagonists, we noted that the cytokine- and PGE2-induced metalloproteinase 9 (MMP-9) expression and activity occurs through EP-1/EP-3/EP-4, an effect downregulated by NF-kappaB inhibitors. CONCLUSIONS Patients with carotid atherosclerosis depict an overexpression of COX-2, mPGES-1 and EPs simultaneously in the PBMC as well as in the vulnerable region of plaques. The studies in cultured monocytic cells suggest that NF-kappaB inhibitors and/or EPs antagonists could represent a novel therapeutic approach to the treatment of plaque instability and rupture.
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Affiliation(s)
- Almudena Gómez-Hernández
- Vascular Research Laboratory, Fundación Jiménez Díaz, Avda Reyes Católicos 2, 28040 Madrid, Spain
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158
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Abstract
Arachidonic acid metabolism plays an important role in acute ischemic syndromes affecting the coronary or cerebrovascular territory, as reflected by biochemical measurements of eicosanoid biosynthesis and the results of inhibitor trials in these settings. Two cyclooxygenase (COX)-isozymes have been characterized, COX-1 and COX-2, that differ in terms of regulatory mechanisms of expression, tissue distribution, substrate specificity, preferential coupling to upstream and downstream enzymes and susceptibility to inhibition by the extremely heterogeneous class of COX-inhibitors. While the role of platelet COX-1 in acute coronary syndromes and ischemic stroke is firmly established through approximately 20 years of thromboxane metabolite measurements and aspirin trials, the role of COX-2 expression and inhibition in atherothrombosis is substantially uncertain, because the enzyme was first characterized in 1991 and selective COX-2 inhibitors became commercially available only in 1998. In this review, we discuss the pattern of expression of COX-2 in the cellular players of atherothrombosis, its role as a determinant of plaque 'vulnerability,' and the clinical consequences of COX-2 inhibition. Recent studies from our group suggest that variable expression of upstream and downstream enzymes in the prostanoid biosynthetic cascade may represent important determinants of the functional consequences of COX-2 expression and inhibition in different clinical settings.
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Affiliation(s)
- F Cipollone
- Atherosclerosis Prevention Center and Clinical Research Center, 'G. d'Annunzio' University Foundation, 'G. d'Annunzio' University of Chieti, Chieti, Italy.
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159
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Cipollone F, Fazia ML, Iezzi A, Cuccurullo C, De Cesare D, Ucchino S, Spigonardo F, Marchetti A, Buttitta F, Paloscia L, Mascellanti M, Cuccurullo F, Mezzetti A. Association Between Prostaglandin E Receptor Subtype EP4 Overexpression and Unstable Phenotype in Atherosclerotic Plaques in Human. Arterioscler Thromb Vasc Biol 2005; 25:1925-31. [PMID: 16020747 DOI: 10.1161/01.atv.0000177814.41505.41] [Citation(s) in RCA: 77] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Objective—
We recently demonstrated that inducible cyclooxygenase/PGE synthase-1 (COX-2/mPGES-1) are overexpressed in symptomatic plaques in association with PGE
2
-dependent metalloproteinase (matrix metalloproteinase [MMP]) biosynthesis and plaque rupture. However, it is not known which of the 4 PGE
2
receptors (EP1–4) mediates macrophage metalloproteinase generation. The aim of this study was to characterize EP1–4 expression in plaques from symptomatic and asymptomatic patients undergoing carotid endarterectomy and correlate it with the extent of inflammatory infiltration, COX-2/mPGES-1 and MMP expression and clinical features of patients’ presentation.
Methods and Results—
Plaques were analyzed for COX-2, mPGES-1, EP1–4, MMP-2, and MMP-9 by immunohistochemistry, reverse-transcription polymerase chain reaction and Western blot; zymography was used to detect MMP activity. We observed strong EP4 immunoreactivity, only very weak staining for EP2, and no expression of EP1 and EP3 in atherosclerotic plaques. EP4 was more abundant in MMP-rich symptomatic lesions, whereas EP2 was no different between symptomatic and asymptomatic plaques. Finally, MMP induction by PGE
2
in vitro was inhibited by the EP4 antagonist L-161 982, but not by its inactive analog L-161 983 or by the EP2 antagonist AH6809.
Conclusions—
This study shows that EP4 overexpression is associated with enhanced inflammatory reaction in atherosclerotic plaques. This effect might contribute to plaque destabilization by inducing culprit metalloproteinase expression.
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MESH Headings
- Aged
- Carotid Artery Diseases/genetics
- Carotid Artery Diseases/immunology
- Carotid Artery Diseases/metabolism
- Cyclooxygenase 2/genetics
- Cyclooxygenase 2/metabolism
- Female
- Gene Expression
- Humans
- Intramolecular Oxidoreductases/genetics
- Intramolecular Oxidoreductases/metabolism
- Macrophages/enzymology
- Macrophages/immunology
- Male
- Matrix Metalloproteinase 2/genetics
- Matrix Metalloproteinase 2/metabolism
- Matrix Metalloproteinase 9/genetics
- Matrix Metalloproteinase 9/metabolism
- Middle Aged
- Phenotype
- Prostaglandin-E Synthases
- Receptors, Prostaglandin E/genetics
- Receptors, Prostaglandin E/metabolism
- Receptors, Prostaglandin E, EP1 Subtype
- Receptors, Prostaglandin E, EP2 Subtype
- Receptors, Prostaglandin E, EP3 Subtype
- Receptors, Prostaglandin E, EP4 Subtype
- Signal Transduction/immunology
- Stroke/genetics
- Stroke/immunology
- Stroke/metabolism
- Vasculitis/genetics
- Vasculitis/immunology
- Vasculitis/metabolism
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Affiliation(s)
- Francesco Cipollone
- Atherosclerosis Prevention Center, G.d'Annunzio University of Chieti, Chieti, Italy.
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160
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McAdam BF, Byrne D, Morrow JD, Oates JA. Contribution of cyclooxygenase-2 to elevated biosynthesis of thromboxane A2 and prostacyclin in cigarette smokers. Circulation 2005; 112:1024-9. [PMID: 16087791 DOI: 10.1161/circulationaha.105.542696] [Citation(s) in RCA: 56] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
BACKGROUND Cigarette smoking is highly pathogenic to the vasculature. In smokers, the biosynthesis of both thromboxane (Tx) A2 and prostacyclin is increased. We hypothesized that the excess in prostacyclin biosynthesis in smokers was derived from the inducible cyclooxygenase-2 (COX-2). We further hypothesized that if the overproduction of prostacyclin in smokers were restraining platelet activation, then inhibition of COX-2 would lead to an increase in the activation of platelets, with a corresponding increase in the biosynthesis of TxA2. METHODS AND RESULTS Smokers and nonsmokers received rofecoxib 25 mg twice daily or placebo for 1 week each in random sequence. The systemic biosynthesis of TxA2 and prostacyclin was assessed by analysis of their respective urinary metabolites, 11-dehydrothromboxane B2 (Tx-M) and 2'3-donor-6-keto-PGF(1alpha) (PGI-M). Serum TxB2 was measured as an indicator of platelet COX-1 activity. Results are expressed as mean+/-SE with median and range. The elevated PGI-M in smokers (189+/-25, median 174, range 85 to 390 pg/mg creatinine) was reduced by rofecoxib to 78+/-27, median 71.5, range 50 to 135 pg/mg creatinine (P=0.002), and in nonsmokers, PGI-M at baseline (115+/-10, median 107, range 67 to 198 pg/mg creatinine) fell to 56+/-15, median 50, range 34 to 125 pg/mg creatinine (P=0.001) with rofecoxib. The increased excretion of Tx-M in smokers (284+/-26, median 252, range 200 to 569 pg/mg creatinine) was reduced by 21% to 223+/-16, median 206, range 154 to 383 pg/mg creatinine by rofecoxib (P=0.04) but was not changed in nonsmokers. Levels of serum TxB2 were not different in smokers and nonsmokers and were unaffected by rofecoxib. CONCLUSIONS The increased prostacyclin biosynthesis in smokers is derived largely from the inducible COX-2. COX-2 also contributes to the increased biosynthesis of TxA2 in smokers, most likely from inflammatory cells.
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Affiliation(s)
- Brendan F McAdam
- Division of Cardiovascular Medicine, Department of Medicine, Vanderbilt University Medical Center, Nashville, TN 37232-8802, USA.
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161
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Affiliation(s)
- Elliott M Antman
- Cardiovascular Division, Department of Medicine, Brigham & Women's Hospital, 75 Francis St, Boston, MA 02115, USA.
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162
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Burleigh ME, Babaev VR, Patel MB, Crews BC, Remmel RP, Morrow JD, Oates JA, Marnett LJ, Fazio S, Linton MF. Inhibition of cyclooxygenase with indomethacin phenethylamide reduces atherosclerosis in apoE-null mice. Biochem Pharmacol 2005; 70:334-42. [PMID: 15950196 DOI: 10.1016/j.bcp.2005.04.044] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2004] [Accepted: 04/14/2005] [Indexed: 11/22/2022]
Abstract
Non-selective inhibition of cyclooxygenase (COX) has been reported to reduce atherosclerosis in both rabbit and murine models. In contrast, selective inhibition of COX-2 has been shown to suppress early atherosclerosis in LDL-receptor null mice but not more advanced lesions in apoE deficient (apoE(-/-)) mice. We investigated the efficacy of the novel COX inhibitor indomethacin phenethylamide (INDO-PA) on the development of different stages of atherosclerotic lesion formation in female apoE(-/-) mice. INDO-PA, which is highly selective for COX-2 in vitro, reduced platelet thromboxane production by 61% in vivo, indicating partial inhibition of COX-1 in vivo. Treatment of female apoE(-/-) mice with 5mg/kg INDO-PA significantly reduced early to intermediate aortic atherosclerotic lesion formation (44 and 53%, respectively) in both the aortic sinus and aorta en face compared to controls. Interestingly, there was no difference in the extent of atherosclerosis in the proximal aorta in apoE(-/-) mice treated from 11 to 21 weeks of age with INDO-PA, yet there was a striking (76%) reduction in lesion size by en face analysis in these mice. These studies demonstrate the ability of non-selective COX inhibition with INDO-PA to reduce early to intermediate atherosclerotic lesion formation in apoE(-/-) mice, supporting a role for anti-inflammatory approaches in the prevention of atherosclerosis.
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Affiliation(s)
- Michael E Burleigh
- Department of Pharmacology, Vanderbilt University Medical Center, Nashville, TN 37232-6300, USA
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163
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De Caterina R, Massaro M. Omega-3 Fatty Acids and the Regulation of Expression of Endothelial Pro-Atherogenic and Pro-Inflammatory Genes. J Membr Biol 2005; 206:103-16. [PMID: 16456721 DOI: 10.1007/s00232-005-0783-2] [Citation(s) in RCA: 76] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2005] [Indexed: 01/19/2023]
Abstract
By partially replacing the corresponding omega-6 analogues in membrane phospholipids, omega-3 fatty acids have been shown to decrease the transcriptional activation of genes--e.g., adhesion molecules, chemoattractants, inflammatory cytokines--involved in endothelial activation in response to inflammatory and pro-atherogenic stimuli. This regulation occurs, at least in part, through a decreased activation of the nuclear factor-kappaB system of transcription factors, secondary to decreased generation of intracellular hydrogen peroxide. Such regulation by omega-3 fatty acids is likely linked to the presence of a higher number of double bonds in the fatty acid chain in omega-3 compared with omega-6 fatty acids. By similar mechanisms, omega-3 fatty acids have been recently shown to reduce gene expression of cyclooxygenase-2, an inflammatory gene involved, through the activation of some metalloproteinases, in plaque angiogenesis and plaque rupture. The quenching of gene expression of pro-inflammatory pro-atherogenic genes by omega-3 fatty acids has consequences on the extent of leukocyte adhesion to vascular endothelium, early atherogenesis and later stages of plaque development and plaque rupture, ultimately yielding a plausible comprehensive explanation for the vasculoprotective effects of these nutrients.
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164
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Hermann M, Enseleit F, Ruschitzka FT. Anti-inflammatory strategies in hypertension: focus on COX-1 and COX-2. Curr Hypertens Rep 2005; 7:52-60. [PMID: 15683587 DOI: 10.1007/s11906-005-0055-7] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
An increasing body of evidence suggests that elevated levels of blood pressure may induce a proinflammatory response. Indeed, both C-reactive protein and blood pressure are independent determinants of cardiovascular risk, and, in combination, each parameter has additional predictive value. Hence, strategies targeted to lower blood pressure and reduce vascular inflammation may potentially provide clinical benefit. In this review, we discuss the role of chronic low-grade inflammation in the context of cardiovascular disease with a focus on roles of cyclooxygenase-1 and -2 in potential anti-inflammatory treatment strategies.
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Affiliation(s)
- Matthias Hermann
- Cardiology, University Hospital Zürich, Rämistrasse 100, 8091 Zürich, Switzerland
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165
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Krotz F, Schiele TM, Klauss V, Sohn HY. Selective COX-2 inhibitors and risk of myocardial infarction. J Vasc Res 2005; 42:312-24. [PMID: 15976506 DOI: 10.1159/000086459] [Citation(s) in RCA: 78] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2005] [Accepted: 04/08/2005] [Indexed: 12/31/2022] Open
Abstract
Selective inhibitors of cyclooxygenase-2 (COX-2, 'coxibs') are highly effective anti-inflammatory and analgesic drugs that exert their action by preventing the formation of prostanoids. Recently some coxibs, which were designed to exploit the advantageous effects of non-steroidal anti-inflammatory drugs while evading their side effects, have been reported to increase the risk of myo cardial infarction and atherothrombotic events. This has led to the withdrawal of rofecoxib from global markets, and warnings have been issued by drug authorities about similar events during the use of celecoxib or valdecoxib/parecoxib, bringing about questions of an inherent atherothrombotic risk of all coxibs and consequences that should be drawn by health care professionals. These questions need to be addressed in light of the known effects of selective inhibition of COX-2 on the cardiovascular system. Although COX-2, in contrast to the cyclooxygenase-1 (COX-1) isoform, is regarded as an inducible enzyme that only has a role in pathophysiological processes like pain and inflammation, experimental and clinical studies have shown that COX-2 is constitutively expressed in tissues like the kidney or vascular endothelium, where it executes important physiological functions. COX-2-dependent formation of prostanoids not only results in the mediation of pain or inflammatory signals but also in the maintenance of vascular integrity. Especially prostacyclin (PGI(2)), which exerts vasodilatory and antiplatelet properties, is formed to a significant extent by COX-2, and its levels are reduced to less than half of normal when COX-2 is inhibited. This review outlines the rationale for the development of selective COX-2 inhibitors and the pathophysiological consequences of selective inhibition of COX-2 with special regard to vasoactive prostaglandins. It describes coxibs that are current ly available, evaluates the current knowledge on the risk of atherothrombotic events associated with their intake and critically discusses the consequences that should be drawn from these insights.
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Affiliation(s)
- Florian Krotz
- Institute of Cardiology, Medical Polyclinic, Ludwig Maximilians University, Munich, Germany.
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166
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Cyrus T, Yao Y, Tung LX, Praticò D. Stabilization of advanced atherosclerosis in low-density lipoprotein receptor-deficient mice by aspirin. Atherosclerosis 2005; 184:8-14. [PMID: 16326168 DOI: 10.1016/j.atherosclerosis.2004.10.047] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/18/2004] [Accepted: 10/12/2004] [Indexed: 11/22/2022]
Abstract
COX-1-dependent eicosanoid formation accelerates atherogenesis, and low-dose aspirin reduces early atherosclerosis. However, the role of aspirin in modulating progression of vascular atherosclerotic lesions once established is less investigated. We wished to determine the effect of low-dose aspirin on vascular inflammation, plaque composition, and progression of established atherosclerosis. Low-density lipoprotein receptor-deficient mice (LDLR(-/-)) were fed a high-fat diet for 3 months. At this time, one group of mice underwent baseline analysis. Two additional groups, while continuing the high-fat diet, were randomized to receive placebo or aspirin for additional 3 months. At the end of the study, LDLR(-/-) mice that had received aspirin had suppressed biosynthesis of thromboxane B2, the major products of COX-1 activity, reduced monocyte chemoattractant protein-1, and soluble intercellular adhesion molecule-1 levels compared with controls. Compared with baseline, the placebo group had significant progression of atherosclerosis. In contrast, aspirin treated mice showed a significant reduction in progression of atherosclerosis, and a significant decrease in foam cell content. These results suggest that in murine atherosclerosis, low-dose aspirin retards progression of established and advanced vascular atherosclerotic lesions by suppressing the formation of bioactive lipids and vascular inflammation.
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Affiliation(s)
- Tillmann Cyrus
- Division of Cardiology, Department of Medicine, Barnes-Jewish Hospital, Washington University School of Medicine, Saint Louis, MO 63110, USA.
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167
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Bennett JS, Daugherty A, Herrington D, Greenland P, Roberts H, Taubert KA. The Use of Nonsteroidal Anti-Inflammatory Drugs (NSAIDs). Circulation 2005; 111:1713-6. [PMID: 15781731 DOI: 10.1161/01.cir.0000160005.90598.41] [Citation(s) in RCA: 61] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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168
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Liu Z, Zhang C, Dronadula N, Li Q, Rao GN. Blockade of Nuclear Factor of Activated T Cells Activation Signaling Suppresses Balloon Injury-induced Neointima Formation in a Rat Carotid Artery Model. J Biol Chem 2005; 280:14700-8. [PMID: 15681847 DOI: 10.1074/jbc.m500322200] [Citation(s) in RCA: 77] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
We have previously reported that nuclear factor of activated T cells (NFATs) play an important role in the regulation of vascular smooth muscle cell migration and proliferation by receptor tyrosine kinase and G protein-coupled receptor agonists, platelet-derived growth factor-BB and thrombin, respectively. To understand the role of NFATs in vascular disease, we have now studied the involvement of these transcription factors in neointima formation in a rat carotid artery balloon injury model. The levels of NFATc1 in injured right common carotid arteries were increased at 72 h, 1 week, and 2 weeks after balloon injury compared with its levels in uninjured left common carotid arteries. Intraperitoneal injection of cyclosporine A (CsA), a pharmacological inhibitor of the calcineurin-NFAT activation pathway, suppressed balloon injury-induced neointima formation by 40%. Similarly, adenoviral-mediated expression of GFPVIVIT, a competent peptide inhibitor of the calcineurin-NFAT activation pathway, in injured arteries also reduced neointima formation by about 40%. Furthermore, CsA and GFPVIVIT attenuated balloon injury-induced neointimal smooth muscle cell proliferation as determined by bromodeoxyuridine staining. Platelet-derived growth factor-BB induced the expression of COX-2 in cultured VSMC in a time- and NFAT-dependent manner. COX-2 expression was also increased in the right common carotid artery in a time-dependent manner after balloon injury as compared with its levels in uninjured left common carotid artery and both CsA and GFPVIVIT negated this response. Together these results for the first time demonstrate that NFATs play a critical role in neointima formation via induction of expression of COX-2.
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Affiliation(s)
- Zhimin Liu
- Department of Physiology, University of Tennessee Health Science Center, Memphis, Tennessee 38163, USA
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169
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Abstract
Our understanding of the role of vitamin E in human nutrition, health, and disease has broadened and changed over the past two decades. Viewed initially as nature's most potent lipid-soluble antioxidant (and discovered for its crucial role in mammalian reproduction) we have now come to realize that vitamin E action has many more facets, depending on the physiological context. Although mainly acting as an antioxidant, vitamin E can also be a pro-oxidant; it can even have nonantioxidant functions: as a signaling molecule, as a regulator of gene expression, and, possibly, in the prevention of cancer and atherosclerosis. Since the term vitamin E encompasses a group of eight structurally related tocopherols and tocotrienols, individual isomers have different propensities with respect to these novel, nontraditional roles. The particular beneficial effects of the individual isomers have to be considered when dissecting the physiological impact of dietary vitamin E or supplements (mainly containing only the alpha-tocopherol isomer) in clinical trials. These considerations are also relevant for the design of transgenic crop plants with the goal of enhancing vitamin E content because an engineered biosynthetic pathway may be biased toward formation of one isomer. In contrast to the tremendous recent advances in knowledge of vitamin E chemistry and biology, there is little hard evidence from clinical and epidemiologic studies on the beneficial effects of supplementation with vitamin E beyond the essential requirement.
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Affiliation(s)
- Claus Schneider
- Division of Clinical Pharmacology, Department of Pharmacology, Vanderbilt University Medical School, Nashville, TN 37232-6602, USA.
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170
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de Winther MPJ, Kanters E, Kraal G, Hofker MH. Nuclear factor kappaB signaling in atherogenesis. Arterioscler Thromb Vasc Biol 2005; 25:904-14. [PMID: 15731497 DOI: 10.1161/01.atv.0000160340.72641.87] [Citation(s) in RCA: 459] [Impact Index Per Article: 23.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
Atherosclerosis is an inflammatory disease, characterized by the accumulation of macrophage-derived foam cells in the vessel wall and accompanied by the production of a wide range of chemokines, cytokines, and growth factors. These factors regulate the turnover and differentiation of immigrating and resident cells, eventually influencing plaque development. One of the key regulators of inflammation is the transcription factor nuclear factor kappaB (NF-kappaB), which, for a long time, has been regarded as a proatherogenic factor, mainly because of its regulation of many of the proinflammatory genes linked to atherosclerosis. NF-kappaB may play an important role in guarding the delicate balance of the atherosclerotic process as a direct regulator of proinflammatory and anti-inflammatory genes and as a regulator of cell survival and proliferation. Here we address recent literature on the function of NF-kappaB in inflammatory responses and its relation to atherosclerosis.
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Affiliation(s)
- Menno P J de Winther
- Department of Molecular Genetics, Cardiovascular Research Institute Maastricht, Maastricht, The Netherlands.
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171
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Abstract
Cyclooxygenase-2 (COX-2) is a highly inducible enzyme exerting diverse actions on cell functions, including proliferation, migration, and DNA damage. Enhanced COX-2 expression may be protective, but excessive expression may be harmful, causing inflammation, atheromatous plaque instability, and intimal hyperplasia. COX-2 transcriptional activation by proinflammatory mediators has been extensively characterized. In this review, the role of C/EBP in regulating COX-2 transcription is highlighted. Recent advances in control of COX-2 transcription by aspirin and salicylate and by a cell cycle-dependent endogenous mechanism are described. The recent progress sheds light on the pathophysiological mechanisms of COX-2 and new transcription-based strategy for controlling COX-2 overexpression and COX-2-mediated cardiovascular diseases.
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Affiliation(s)
- Kenneth K Wu
- Vascular Biology Research Center, Institute of Molecular Medicine and Division of Hematology, University of Texas Health Science Center at Houston, 6431 Fannin, MSB 5.016, Houston, TX 77030, USA.
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172
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Egan KM, Wang M, Fries S, Lucitt MB, Zukas AM, Puré E, Lawson JA, FitzGerald GA. Cyclooxygenases, Thromboxane, and Atherosclerosis. Circulation 2005; 111:334-42. [PMID: 15655126 DOI: 10.1161/01.cir.0000153386.95356.78] [Citation(s) in RCA: 149] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Background—
Antagonism or deletion of the receptor (the TP) for the cyclooxygenase (COX) product thromboxane (Tx)A
2
, retards atherogenesis in apolipoprotein E knockout (ApoE KO) mice. Although inhibition or deletion of COX-1 retards atherogenesis in ApoE and LDL receptor (LDLR) KOs, the role of COX-2 in atherogenesis remains controversial. Other products of COX-2, such as prostaglandin (PG) I
2
and PGE
2
, may both promote inflammation and restrain the effects of TxA
2
. Thus, combination with a TP antagonist might reveal an antiinflammatory effect of a COX-2 inhibitor in this disease. We addressed this issue and the role of TxA
2
in the promotion and regression of diffuse, established atherosclerosis in Apobec-1/LDLR double KOs (DKOs).
Methods and Results—
TP antagonism with S18886, but not combined inhibition of COX-1 and COX-2 with indomethacin or selective inhibition of COX-2 with Merck Frosst (MF) tricyclic, retards significantly atherogenesis in DKOs. Although indomethacin depressed urinary excretion of major metabolites of both TxA
2
, 2,3-dinor TxB
2
(Tx-M), and PGI
2
, 2,3-dinor 6-keto PGF
1α
(PGI-M), only PGI-M was depressed by the COX-2 inhibitor. None of the treatments modified significantly the increase in lipid peroxidation during atherogenesis, reflected by urinary 8,12-iso-iPF
2α
-VI. Combination with the COX-2 inhibitor failed to augment the impact of TP antagonism alone on lesion area. Rather, analysis of plaque morphology reflected changes consistent with destabilization of the lesion coincident with augmented formation of TxA
2
. Despite a marked effect on disease progression, TP antagonism failed to induce regression of established atherosclerotic disease in this model.
Conclusions—
TP antagonism is more effective than combined inhibition of COX-1 and COX-2 in retarding atherogenesis in Apobec-1/LDLR DKO mice, which perhaps reflects activation of the receptor by multiple ligands during disease initiation and early progression. Despite early intervention, selective inhibition of COX-2, alone or in combination with a TP antagonist, failed to modify disease progression but may undermine plaque stability when combined with the antagonist. TP antagonism failed to induce regression of established atherosclerotic disease. TP ligands, including COX-1 (but not COX-2)–derived TxA
2
, promote initiation and early progression of atherogenesis in Apobec-1/LDLR DKOs but appear unimportant in the maintenance of established disease.
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Affiliation(s)
- Karine M Egan
- Institute for Translational Medicine and Therapeutics, University of Pennsylvania, Philadelphia, PA 19104, USA
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173
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Fries S, Grosser T. The cardiovascular pharmacology of COX-2 inhibition. HEMATOLOGY. AMERICAN SOCIETY OF HEMATOLOGY. EDUCATION PROGRAM 2005:445-51. [PMID: 16304418 DOI: 10.1182/asheducation-2005.1.445] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/05/2023]
Abstract
Selective inhibitors of cyclooxygenase (COX)-2, the coxibs, were developed to inhibit inflammatory prostaglandins derived from COX-2, while sparing gastroprotective prostaglandins primarily formed by COX-1. However, COX-2-derived prostaglandins mediate not only pain and inflammation but also affect vascular function, the regulation of hemostasis/ thrombosis, and blood pressure control. All coxibs depress COX-2-dependent prostacyclin (PGI(2)) biosynthesis without effective suppression of platelet COX-1-derived thromboxane (Tx) A(2), unlike aspirin or traditional nonsteroidal anti-inflammatory drugs, which inhibit both COX-1 and COX-2. The actions of PGI(2) oppose mediators, which stimulate platelets, elevate blood pressure, and accelerate atherogenesis, including TxA(2). Indeed, structurally distinct inhibitors of COX-2 have increased the likelihood of hypertension, myocardial infarction and stroke in controlled clinical trials. The detection of these events in patients is related to the duration of exposure and to their baseline risk of cardiovascular disease. Thus, coxibs should be withheld from patients with preexisting cardiovascular risk factors, and exposed patients at low cardiovascular baseline risk should be monitored for changes in their risk factor profile, such as increases in arterial blood pressure.
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Affiliation(s)
- Susanne Fries
- Institute for Translational Medicine and Therapeutics, University of Pennsylvania School of Medicine, 809 Biomedical Research Building, 421 Curie Blvd., Philadelphia, PA 19104-6084, USA
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174
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Kobayashi T, Tahara Y, Matsumoto M, Iguchi M, Sano H, Murayama T, Arai H, Oida H, Yurugi-Kobayashi T, Yamashita JK, Katagiri H, Majima M, Yokode M, Kita T, Narumiya S. Roles of thromboxane A(2) and prostacyclin in the development of atherosclerosis in apoE-deficient mice. J Clin Invest 2004; 114:784-94. [PMID: 15372102 PMCID: PMC516261 DOI: 10.1172/jci21446] [Citation(s) in RCA: 121] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2004] [Accepted: 07/27/2004] [Indexed: 12/30/2022] Open
Abstract
Production of thromboxane (TX) A2 and PG I2/prostacyclin (PGI2) is increased in patients with atherosclerosis. However, their roles in atherogenesis have not been critically defined. To examine this issue, we cross-bred atherosclerosis-prone apoE-deficient mice with mice deficient in either the TXA receptor (TP) or the PGI receptor (IP). Although they showed levels of serum cholesterol and triglyceride similar to those of apoE-deficient mice, apoE-/-TP-/- mice exhibited a significant delay in atherogenesis, and apoE-/-IP-/- mice exhibited a significant acceleration in atherogenesis compared with mice deficient in apoE alone. The plaques in apoE-/-IP-/- mice showed partial endothelial disruption and exhibited enhanced expression of ICAM-1 and decreased expression of platelet endothelial cell adhesion molecule 1 (PECAM-1) in the overlying endothelial cells compared with those of apoE-/-TP-/- mice. Platelet activation with thrombin ex vivo revealed higher and lower sensitivity for surface P-selectin expression in platelets of apoE-/-IP-/- and apoE-/-TP-/- mice, respectively, than in those of apoE-/- mice. Intravital microscopy of the common carotid artery revealed a significantly greater number of leukocytes rolling on the vessel walls in apoE-/-IP-/- mice than in either apoE-/-TP-/- or apoE-/- mice. We conclude that TXA2 promotes and PGI2 prevents the initiation and progression of atherogenesis through control of platelet activation and leukocyte-endothelial cell interaction.
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Affiliation(s)
- Takuya Kobayashi
- Department of Pharmacology, Kyoto University Faculty of Medicine, Japan
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175
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Mouithys-Mickalad A, Deby-Dupont G, Dogne JM, de Leval X, Kohnen S, Navet R, Sluse F, Hoebeke M, Pirotte B, Lamy M. Effects of COX-2 inhibitors on ROS produced by Chlamydia pneumoniae-primed human promonocytic cells (THP-1). Biochem Biophys Res Commun 2004; 325:1122-30. [PMID: 15555544 DOI: 10.1016/j.bbrc.2004.10.155] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2004] [Indexed: 11/30/2022]
Abstract
Chronic inflammation through foam cells and macrophages is important in atherosclerosis development, and can be considered as therapeutic targets. Cyclooxygenase and NADPH-oxidase were expressed within atherosclerotic lesions. Reactive oxygen species produced by NADPH oxidase were found to trigger the cyclooxygenase-2 expression. The effects of preferential COX-2 inhibitors on ROS produced by Chlamydia-primed human monocytes (THP-1 cells) were evaluated by fluorescence, chemiluminescence, oxymetry, and EPR spin trapping. Fluorescence assays showed an increased production of ROS with Chlamydia versus cells primed by 10(-8)M PMA. COX-2 inhibitors inhibited in a dose-dependent manner the luminol-enhanced CL while ibuprofen and diclofenac increased the chemiluminescence response. By EPR spin trapping, COX-2 inhibitors, ibuprofen, and diclofenac, exhibited a dose-dependent inhibiting effect (10 and 100muM) on the EPR signal appearance. Our cell model combining EPR, chemiluminescence, and oxymetry appeared relevant to study the modulating effects of preferential COX-2 inhibitors on the cell oxidant activity and chronic inflammatory diseases.
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Affiliation(s)
- Ange Mouithys-Mickalad
- Centre for Oxygen, Research and Development (C.O.R.D.), Institut de Chimie, B6a, University of Liège, Sart Tilman, 4000 Liège, Belgium.
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176
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Beloqui O, Páramo JA, Orbe J, Benito A, Colina I, Monasterio A, Díez J. Monocyte cyclooxygenase-2 overactivity: a new marker of subclinical atherosclerosis in asymptomatic subjects with cardiovascular risk factors? Eur Heart J 2004; 26:153-8. [PMID: 15618071 DOI: 10.1093/eurheartj/ehi016] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
AIMS Cyclooxygenase-2 (COX-2)-mediated prostaglandin production by activated macrophages is associated with inflammation and atherosclerosis. We investigated the relationship between COX-2-mediated prostaglandin-E2 (PGE2) release, cardiovascular risk factors, and carotid atherosclerosis in apparently healthy subjects. METHODS AND RESULTS PGE2 release by lipopolysaccharide-stimulated blood monocytes was measured by ELISA in 291 subjects (76.5% men, mean age 58) who underwent global vascular risk assessment and carotid ultrasonography. COX-2 expression (real-time RT-PCR) was analysed in a subgroup of 100 subjects (76% men, mean age 59). Inducible PGE2 production was associated with smoking and diabetes (P<0.05), but not with arterial hypertension, dyslipidaemia, or obesity. Subjects in the highest tertile of PGE2 (>8.1 ng/mL) had significantly higher mean carotid intima-media thickness (IMT) than those in the lowest tertile (P<0.01). No significant differences among tertiles were observed in the levels of inflammatory markers (C-reactive protein, fibrinogen, and von Willebrand factor). The association between PGE2 and carotid IMT remained statistically significant (P=0.012) after adjustment for a number of cardiovascular and inflammatory risk factors. A correlation between COX-2 expression and PGE2 production was observed (P<0.005). CONCLUSIONS COX-2-mediated PGE2 overproduction by stimulated monocytes might provide a new marker of subclinical atherosclerosis in asymptomatic subjects exposed to cardiovascular risk factors.
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Affiliation(s)
- Oscar Beloqui
- Department of Internal Medicine, University Clinic, Clínica Universitaria, Avenida de Pío XII 36, 31008 Pamplona, Spain.
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177
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Rue CA, Jarvis MA, Knoche AJ, Meyers HL, DeFilippis VR, Hansen SG, Wagner M, Früh K, Anders DG, Wong SW, Barry PA, Nelson JA. A cyclooxygenase-2 homologue encoded by rhesus cytomegalovirus is a determinant for endothelial cell tropism. J Virol 2004; 78:12529-36. [PMID: 15507640 PMCID: PMC525102 DOI: 10.1128/jvi.78.22.12529-12536.2004] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
Cyclooxygenase-2 (COX-2) is a cellular enzyme in the eicosanoid synthetic pathway that mediates the synthesis of prostaglandins from arachidonic acid. The eicosanoids function as critical regulators of a number of cellular processes, including the acute and chronic inflammatory response, hemostasis, and the innate immune response. Human cytomegalovirus (HCMV), which does not encode a viral COX-2 isoform, has been shown to induce cellular COX-2 expression. Importantly, although the precise role of COX-2 in CMV replication is unknown, COX-2 induction was shown to be critical for normal HCMV replication. In an earlier study, we identified an open reading frame (Rh10) within the rhesus cytomegalovirus (RhCMV) genome that encoded a putative protein (designated vCOX-2) with high homology to cellular COX-2. In the current study, we show that vCOX-2 is expressed with early-gene kinetics during RhCMV infection, resulting in production of a 70-kDa protein. Consistent with the expression of a viral COX-2 isoform, cellular COX-2 expression was not induced during RhCMV infection. Finally, analysis of growth of recombinant RhCMV with vCOX-2 deleted identified vCOX-2 as a critical determinant for replication in endothelial cells.
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Affiliation(s)
- Cary A Rue
- Department of Molecular Microbiology and Immunology, 3181 SW Sam Jackson Road, Oregon Health Sciences University, Portland, OR 97239, USA
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178
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Bunderson M, Brooks DM, Walker DL, Rosenfeld ME, Coffin JD, Beall HD. Arsenic exposure exacerbates atherosclerotic plaque formation and increases nitrotyrosine and leukotriene biosynthesis. Toxicol Appl Pharmacol 2004; 201:32-9. [PMID: 15519606 DOI: 10.1016/j.taap.2004.04.008] [Citation(s) in RCA: 88] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2003] [Accepted: 04/19/2004] [Indexed: 10/26/2022]
Abstract
A correlation between arsenic and cardiovascular disease (CVD) has been established through epidemiological studies, although the mechanisms are unknown. Using a mouse model that develops atherosclerotic lesions on a normal chow diet, we have confirmed a connection between long-term arsenic intake and CVD. Our results reveal a significant increase in the degree of atherosclerotic plaque stenosis within the innominate artery of ApoE-/-/LDLr-/- mice treated with 10 ppm sodium arsenite (133 microM) in drinking water for 18 weeks compared to controls. Immunohistochemistry shows nitrotyrosine formation, a marker of reactive nitrogen species generation, is significantly higher within the atherosclerotic plaque of arsenic-treated mice. In addition, there is a significant increase in the 5-lipoxygenase (5-LO) product, leukotriene E4 (LTE4), in the serum of arsenic-treated mice. This is supported by induction of the 5-LO protein and subsequent increases in LTE4 synthesis in bovine aortic endothelial cells. This increase in LTE4 is partially inhibited by inhibitors of nitric oxide synthase, suggesting a link between reactive nitrogen species and arsenic-induced inflammation. Furthermore, there is a significant increase in prostacyclin (PGI2) in the serum of arsenic-treated mice. We conclude that changes in specific inflammatory mediators such as LTE4 and PGI2 are related to arsenic-induced atherosclerosis. In addition, amplified synthesis of reactive species such as peroxynitrite results in increased protein nitration in response to arsenic exposure. This finding is consistent with the pathology seen in human atherosclerotic plaques.
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Affiliation(s)
- Melisa Bunderson
- Center for Environmental Health Sciences, University of Montana, Missoula, MT 59812-1552, USA
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179
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Abstract
Atherosclerosis is now understood to be a disease characterized by inflammation that results in a host of complications, including ischemia, acute coronary syndromes (unstable angina pectoris and myocardial infarction), and stroke. Inflammation may be caused by a response to oxidized low-density lipoproteins, chronic infection, or other factors; and markers of this process, such as C-reactive protein, may be useful to predict an increased risk of coronary heart disease. Thus, we believe that inflammatory processes may be potential targets of therapy in preventing or treating atherosclerosis and its complications.
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Affiliation(s)
- Rodolfo Paoletti
- Department of Pharmacological Sciences, University of Milan, via Balzaretti 9, 20133, Milan, Italy.
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180
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Muralidhar B, Carpenter KLH, Müller K, Skepper JN, Arends MJ. Potency of arachidonic acid in polyunsaturated fatty acid-induced death of human monocyte-macrophages: implications for atherosclerosis. Prostaglandins Leukot Essent Fatty Acids 2004; 71:251-262. [PMID: 15301796 DOI: 10.1016/j.plefa.2004.03.020] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/20/2003] [Accepted: 03/17/2004] [Indexed: 12/23/2022]
Abstract
Evidence suggests that oxidation of LDL is involved in the progression of atherosclerosis by inducing apoptosis in macrophages. Polyunsaturated fatty acids (PUFAs) are prominent components of LDL and are highly peroxidisable. We therefore tested PUFAs for induction of apoptosis in human monocyte-macrophages in vitro. Arachidonic acid (AA) induced the highest levels of apoptosis followed by docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA), despite DHA and EPA being more peroxidisable than AA. alpha-Linolenic acid induced lower levels of apoptosis. Linoleic and oleic acids were innocuous. Results of experiments with AA products and enzyme inhibitors suggest roles for peroxidation, cyclooxygenase and lipoxygenase in AA-induced apoptosis. Our results further suggest activation of PPARgamma by AA and DHA associated with apoptosis induction. These findings may be relevant to potential mechanisms of fatty acid influences on plaques and may suggest strategies for combating atherosclerosis progression.
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Affiliation(s)
- Balaji Muralidhar
- Department of Pathology, University of Cambridge, Tennis Court Road, Cambridge CB2 1QP, UK
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181
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Justice E, Carruthers DM. Cardiovascular risk and COX-2 inhibition in rheumatological practice. J Hum Hypertens 2004; 19:1-5. [PMID: 15385947 DOI: 10.1038/sj.jhh.1001777] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
The use of specific COX-2 inhibitors in place of standard nonsteroidals for the treatment of arthritis appears to reduce the risk of serious gastrointestinal toxicity in this group of patients. However, the role played by these inhibitors in the generation or exacerbation of ischaemic cardiovascular disease is less clear. Clinical studies demonstrate that hypertension can be induced or aggravated by COX-2 inhibitors to a degree similar to that which occurs with standard nonsteroidals. Endothelial dysfunction, an indicator of cardiac ischaemia, may also be exacerbated by specific COX-2 inhibition and there is much debate as to whether these changes lead to an absolute increase in ischaemic cardiac events. These effects on cardiovascular risk factors appear all the more important in patients with rheumatoid arthritis where there is an increase in the incidence of ischaemic heart disease. Here we review the available data on COX-2 inhibition and cardiovascular disease and conclude that all patients who started these agents should have a careful assessment and modification of any cardiovascular risk factors.
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Affiliation(s)
- E Justice
- Department of Rheumatology, Sandwell and West Birmingham Hospitals Trust, City Hospital, Dudley Road, Birmingham, UK
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182
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Kobayashi T, Tahara Y, Matsumoto M, Iguchi M, Sano H, Murayama T, Arai H, Oida H, Yurugi-Kobayashi T, Yamashita JK, Katagiri H, Majima M, Yokode M, Kita T, Narumiya S. Roles of thromboxane A2 and prostacyclin in the development of atherosclerosis in apoE-deficient mice. J Clin Invest 2004. [DOI: 10.1172/jci200421446] [Citation(s) in RCA: 267] [Impact Index Per Article: 12.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023] Open
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183
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Bogaty P, Brophy JM, Noel M, Boyer L, Simard S, Bertrand F, Dagenais GR. Impact of prolonged cyclooxygenase-2 inhibition on inflammatory markers and endothelial function in patients with ischemic heart disease and raised C-reactive protein: a randomized placebo-controlled study. Circulation 2004; 110:934-9. [PMID: 15302800 DOI: 10.1161/01.cir.0000139338.12464.5f] [Citation(s) in RCA: 71] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
BACKGROUND The impact of cyclooxygenase (COX)-2 antagonist treatment on acute coronary risk is controversial. We investigated the effect of prolonged COX-2 inhibition on inflammatory profile and endothelial function in patients with ischemic heart disease and high serum C-reactive protein (CRP) values. METHODS AND RESULTS In a double-blind study, 35 stable subjects on low-dose aspirin with > or =2 previous acute coronary events and 2 of 2 screening CRP values >2.0 mg/L were randomized to the COX-2 inhibitor rofecoxib (25 mg) or placebo daily for 6 months. Serum CRP, interleukin-6 (IL-6), P-selectin, matrix metalloproteinase-9 (MMP-9), and brachial artery endothelial function were evaluated. In the placebo group, CRP (median) was 3.16 mg/L (25% and 75% quartiles, 1.90 and 5.78 mg/L) at baseline and 4.22 mg/L (25% and 75% quartiles, 2.04 and 6.25 mg/L) at 6 months; in the rofecoxib group, CRP was 3.45 mg/L (25% and 75% quartiles, 2.08 and 5.78 mg/L) at baseline and 1.41 mg/L (25% and 75% quartiles, 1.17 and 4.81 mg/L) at 6 months (P=0.03). Rofecoxib compared with placebo also lowered IL-6 at 6 months (P=0.0002). There was a significant off-drug effect on CRP and IL-6 levels in the rofecoxib group 3 months after treatment (P=0.005 and P=0.009, respectively). Rofecoxib did not significantly affect P-selectin, MMP-9, and brachial artery vasoreactivity. CONCLUSIONS Prolonged COX-2 inhibition attenuates CRP and IL-6, does not modify P-selectin and MMP-9, and has no deleterious effect on endothelial function in stable patients with a history of recurrent acute coronary events and raised CRP. These results strengthen the rationale for evaluating the clinical benefit of COX-2 inhibition in patients with ischemic heart disease.
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Affiliation(s)
- Peter Bogaty
- Quebec Heart Institute/Laval Hospital, Laval University, 2725 Chemin Ste-Foy, Quebec City, Quebec, Canada G1V 4G5.
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184
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Fischer JW, Hawkins S, Clowes AW. Pharmacologic inhibition of nitric oxide synthases and cyclooxygenases enhances intimal hyperplasia in balloon-injured rat carotid arteries. J Vasc Surg 2004; 40:115-22. [PMID: 15218471 PMCID: PMC1381983 DOI: 10.1016/j.jvs.2004.03.037] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
OBJECTIVE Extensive proliferation and migration of smooth muscle cells (SMCs) contribute to development of fibromuscular intimal hyperplasia in response to balloon catheter-induced injury of the left carotid artery in Fischer 344 rats. The purpose of the present study was to test the hypothesis that endogenously generated nitric oxide (NO) and prostaglandins act synergistically to limit the extent of neointimal hyperplasia. METHODS The left carotid artery of Fischer 344 rats was injured with a 2F balloon catheter. The following treatment was initiated 24 hours before arterial injury, and was continued for 2 weeks: N-nitro-l-arginine (L-NA; 10 mg/kg/d, in drinking water), indomethacin (1.5 mg/kg/d per gavage), and L-NA (10 mg/kg/d) plus indomethacin (1.5 mg/kg/d). After application of an overdose of pentobarbital animals were formalin-fixed. Subsequently, paraffin-embedded cross sections of the uninjured and injured carotid arteries were analyzed morphometrically. SMC proliferation was determined by incorporation of 5-bromo-2'-deoxyuridine. RESULTS Two weeks after injury, L-NA caused a 1.29-fold +/- 0.29-fold (mean +/- SD; n = 14; P <.05) increase in the intima-media ratio, compared with control animals, whereas indomethacin had no effect. Combined treatment with L-NA plus indomethacin further increased intima-media ratio (1.65-fold +/- 0.5-fold over control; n = 14; P <.05). SMC proliferation in the neointima of rats treated with L-NA and L-NA plus indomethacin was elevated. Furthermore, neointimal cell density (nuclei per square millimeter) was reduced after combined inhibition of cyclooxygenases and NO synthases. CONCLUSION The present results of pharmacologic NO synthase and cyclooxygenase inhibition suggest that NO and prostaglandins are part of an endogenous growth inhibitory mechanism that synergistically suppresses intimal thickening. CLINICAL RELEVANCE The role of cyclooxygenase-1 (COX1) and cyclooxygenase-2 (COX2) during vascular recurrent stenosis and atherosclerosis is not clear yet. In particular, the effects of selective COX2 inhibitors on the frequency of cardiovascular events is still controversial. It is shown here in rats that the application of a non-selective COX inhibitor does not affect arterial stenosis. However, the concurrent inhibition of endogenous nitric oxide generation and COX1 or COX2 causes overshooting neointimal hyperplasia. These results suggest that increased vascular stenosis can result from administration of drugs that pharmacologically block 2 or more inhibitory pathways that normally counterbalance the effect of promotors of neointimal hyperplasia.
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Affiliation(s)
- Jens W Fischer
- Molekulare Pharmakologie, Institut für Pharmakologie und Klinische Pharmakologie, Universitätsklinikum Düsseldorf, Germany.
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185
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Michelsen KS, Wong MH, Shah PK, Zhang W, Yano J, Doherty TM, Akira S, Rajavashisth TB, Arditi M. Lack of Toll-like receptor 4 or myeloid differentiation factor 88 reduces atherosclerosis and alters plaque phenotype in mice deficient in apolipoprotein E. Proc Natl Acad Sci U S A 2004; 101:10679-84. [PMID: 15249654 PMCID: PMC489994 DOI: 10.1073/pnas.0403249101] [Citation(s) in RCA: 801] [Impact Index Per Article: 38.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023] Open
Abstract
Toll-like receptors (TLRs) and the downstream adaptor molecule myeloid differentiation factor 88 (MyD88) play an essential role in the innate immune responses. Here, we demonstrate that genetic deficiency of TLR4 or MyD88 is associated with a significant reduction of aortic plaque areas in atherosclerosis-prone apolipoprotein E-deficient mice, despite persistent hypercholesterolemia, implying an important role for the innate immune system in atherogenesis. Apolipoprotein E-deficient mice that also lacked TLR4 or MyD88 demonstrated reduced aortic atherosclerosis that was associated with reductions in circulating levels of proinflammatory cytokines IL-12 or monocyte chemoattractant protein 1, plaque lipid content, numbers of macrophage, and cyclooxygenase 2 immunoreactivity in their plaques. Endothelial-leukocyte adhesion in response to minimally modified low-density lipoprotein was reduced in aortic endothelial cells derived from MyD88-deficient mice. Taken together, our results suggest an important role for TLR4 and MyD88 signaling in atherosclerosis in a hypercholesterolemic mouse model, providing a pathophysiologic link between innate immunity, inflammation, and atherogenesis.
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MESH Headings
- Adaptor Proteins, Signal Transducing
- Animals
- Antigens, Differentiation/genetics
- Antigens, Differentiation/immunology
- Aorta/cytology
- Aorta/pathology
- Apolipoproteins E/genetics
- Apolipoproteins E/metabolism
- Arteriosclerosis/genetics
- Arteriosclerosis/immunology
- Arteriosclerosis/pathology
- Cells, Cultured
- Chemokine CCL2/metabolism
- Cyclooxygenase 2
- Endothelial Cells/cytology
- Endothelial Cells/metabolism
- Female
- Humans
- Immunity, Innate/physiology
- Interleukin-12/blood
- Isoenzymes/metabolism
- Lipid Metabolism
- Lipids/chemistry
- Macrophages/metabolism
- Male
- Membrane Glycoproteins/genetics
- Membrane Glycoproteins/immunology
- Membrane Proteins
- Mice
- Mice, Inbred C57BL
- Mice, Knockout
- Myeloid Differentiation Factor 88
- Phenotype
- Prostaglandin-Endoperoxide Synthases/metabolism
- Receptors, Cell Surface/genetics
- Receptors, Cell Surface/immunology
- Receptors, Immunologic/genetics
- Receptors, Immunologic/immunology
- Signal Transduction/physiology
- Toll-Like Receptor 4
- Toll-Like Receptors
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Affiliation(s)
- Kathrin S Michelsen
- Division of Pediatric Infectious Diseases, Atherosclerosis Research Center, Burns and Allen Research Institute, Cedars-Sinai Medical Center and David Geffen School of Medicine, University of California, Los Angeles, CA 90048, USA
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186
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Niederberger E, Manderscheid C, Grösch S, Schmidt H, Ehnert C, Geisslinger G. Effects of the selective COX-2 inhibitors celecoxib and rofecoxib on human vascular cells. Biochem Pharmacol 2004; 68:341-50. [PMID: 15194006 DOI: 10.1016/j.bcp.2004.03.029] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2004] [Accepted: 03/30/2004] [Indexed: 01/28/2023]
Abstract
Rheumatoid arthritis (RA) is associated with a reduced life expectancy considered to be partly caused by cardiovascular events. A growing concern is that accelerated atherosclerosis is driven by inflammatory mechanisms similar to those responsible for RA. Therefore, selective COX-2 inhibitors, which are widely used for the symptomatic treatment of pain and inflammation in RA, may have an impact on atherosclerotic processes. Their anti-inflammatory properties might provoke anti-atherogenic effects but on the other hand, selective inhibition of anti-thrombotic prostacyclin and COX-2 independent effects might promote the risk of increased prothrombotic activity. In the current study, the effects of the presently marketed selective COX-2 inhibitors celecoxib and rofecoxib on vascular cells have been investigated. Celecoxib inhibited the proliferation of human umbilical vein endothelial cells (HUVECs) in a concentration-dependent manner. At high concentrations, it induced apoptosis and the modulation of inhibitory cell cycle proteins. In contrast rofecoxib-even at high concentrations-had no effect on cell proliferation, apoptosis or cell cycle distribution indicating that celecoxib and rofecoxib do not affect the same signal transduction pathways in endothelial cells. Both drugs did not affect apoptosis induction or cell cycle proliferation in human vascular smooth muscle cells. The observed effects on endothelial cells appear to be COX-independent since both drugs selectively inhibited COX-2-activity and the applied concentrations lay beyond the IC(50) for inhibition of prostacyclin production. Regarding endothelial apoptosis as a relevant event in the initiation and progression of atherosclerosis the present data put forward the hypothesis that the presently marketed COX-2 inhibitors have a different impact on atherosclerotic processes.
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Affiliation(s)
- Ellen Niederberger
- Pharmazentrum frankfurt, Klinikum der Johann Wolfgang Goethe-Universität Frankfurt, Theodor Stern Kai 7, 60590 Frankfurt am Main, Germany.
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187
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Davies NM, Teng XW, Skjodt NM. Pharmacokinetics of rofecoxib: a specific cyclo-oxygenase-2 inhibitor. Clin Pharmacokinet 2004; 42:545-56. [PMID: 12793839 DOI: 10.2165/00003088-200342060-00004] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
Rofecoxib is a commonly used specific cyclo-oxygenase-2 (COX-2) inhibitor. Rofecoxib has high bioavailability, poor aqueous solubility, an elimination half-life suitable for daily administration and a volume of distribution approximating body mass. Species-specific, predominantly hepatic, metabolism occurs, with novel enterohepatic circulation in rats and O-glucuronidation by uridine diphosphate-glucuronosyl transferase (UGT) 2B7 and 2B15 in human liver microsomes. Discrepancies in studies of postoperative analgesia can be putatively explained by known pharmacokinetics. Changes in rofecoxib disposition and pharmacokinetics are evident between races, in elderly patients, in patients with chronic renal insufficiency and in patients with mild to moderate hepatic impairment. Despite the selective action of COX-2 inhibitors, there remains the potential for significant drug interactions. Rofecoxib has been shown to have interactions with rifampicin (rifampin), warfarin, lithium and angiotensin converting enzyme (ACE) inhibitors and theophylline. COX-2 inhibitors represent a major therapeutic advance in terms of gastrointestinal safety; however, long-term safety in other organ systems and with concomitant drug administration still remain to be proven.
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Affiliation(s)
- Neal M Davies
- Department of Pharmaceutical Sciences, College of Pharmacy, Washington State University, Pullman, Washington 99164, USA.
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188
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Abstract
Inflammation occurs in the vasculature as a response to injury, lipid peroxidation, and perhaps infection. Various risk factors, including hypertension, diabetes, and smoking, are amplified by the harmful effects of oxidized low-density-lipoprotein cholesterol, initiating a chronic inflammatory reaction, the result of which is a vulnerable plaque, prone to rupture and thrombosis. Epidemiological and clinical studies have shown strong and consistent relationships between markers of inflammation and risk of future cardiovascular events. Inflammation can potentially be detected locally by imaging techniques as well as emerging techniques, such as identification of temperature or pH heterogeneity. It can be detected systemically by measurement of inflammatory markers. Of these, the most reliable and accessible for clinical use is currently high-sensitivity C-reactive protein. A combination of methods may provide the best identification of persons at risk for cardiovascular events who would benefit from treatment. In randomized, controlled trials, 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase inhibitors, in the form of statins, have been shown to provide effective therapy for lowering CRP, in conjunction with their lipid-lowering effects. Although the magnitude of risk reduction associated with statin use appears to be largest for those with the highest serum levels of CRP, whether CRP reduction per se lowers cardiovascular risk is unknown.
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Affiliation(s)
- James T Willerson
- University of Texas Health Science Center and Texas Heart Institute at Houston, 77225, USA.
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189
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Gross GJ, Moore J. Effect of COX-1/COX-2 Inhibition versus Selective COX-2 Inhibition on Coronary Vasodilator Responses to Arachidonic Acid and Acetylcholine. Pharmacology 2004; 71:135-42. [PMID: 15161995 DOI: 10.1159/000077447] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2003] [Accepted: 11/15/2003] [Indexed: 11/19/2022]
Abstract
The effect of a nonselective COX-1/COX-2 inhibitor, naproxen, was compared with a COX-2-selective inhibitor (SC-58236) on coronary vasodilatory responses in the anesthetized dog. Coronary vasodilation was induced by direct intracoronary injection of acetylcholine (ACH) and arachidonic acid (AA) in control animals and in those treated with either naproxen (1, 3, or 10 mg/kg p.o. 24 h prior to the experiment) or SC-58236 (1, 5, or 15 mg/kg p.o. 24 h prior to the experiment). Naproxen, at 10 mg/kg, significantly attenuated the AA-induced vasodilation (prostacyclin dependent) with no effect on ACH-induced vasodilation (nitric oxide dependent). SC-58236 failed to attenuate either AA- or ACH-induced vasodilation. Ex vivo assays were utilized to establish inhibition of COX-2 (lipopolysaccharide-stimulated prostaglandin E2 formation) and COX-1 (serum thromboxane B2) in blood taken from dogs administered 1, 3, or 10 mg/kg naproxen or 15 mg/kg SC-58236. Naproxen (3 and 10 mg/kg) and SC-58236 (15 mg/kg) markedly reduced the lipopolysaccharide-induced prostaglandin E2 formation, whereas SC- 58236 (15 mg/kg) had no effect on serum thromboxane B2. Naproxen significantly reduced thromboxane B2 at all three doses studied. Furthermore, naproxen (10 mg/kg p.o.) significantly inhibited the AA-induced platelet aggregation (thromboxane B2 dependent), whereas SC-58236 had no effect. Collectively, these results demonstrate that SC-58236 is selective for COX-2, while naproxen is a nonselective inhibitor. These data also suggest that vasodilatory responses to AA in the dog are primarily COX-1 dependent. Selective COX-2 inhibition does not affect either prostacyclin or nitric oxide mediated vasodilation in the canine coronary circulation.
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Affiliation(s)
- Garrett J Gross
- Department of Pharmacology and Toxicology, Medical College of Wisconsin, Milwaukee, Wisc. 53226-3548, USA.
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190
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Abstract
Type 2 diabetes is associated with significantly accelerated rates of macrovascular complications such as atherosclerosis. Emerging evidence now indicates that atherosclerosis is an inflammatory disease and that certain inflammatory markers may be key predictors of diabetic atherosclerosis. Proinflammatory cytokines and cellular adhesion molecules expressed by vascular and blood cells during stimulation by growth factors and cytokines seem to play major roles in the pathophysiology of atherosclerosis and diabetic vascular complications. However, more recently, data suggest that inflammatory responses can also be elicited by smaller oxidized lipids that are components of atherogenic oxidized low-density lipoprotein or products of phospholipase activation and arachidonic acid metabolism. These include oxidized lipids of the lipoxygenase and cyclooxygenase pathways of arachidonic acid and linoleic acid metabolism. These lipids have potent growth, vasoactive, chemotactic, oxidative, and proinflammatory properties in vascular smooth muscle cells, endothelial cells, and monocytes. Cellular and animal models indicate that these enzymes are induced under diabetic conditions, have proatherogenic effects, and also mediate the actions of growth factors and cytokines. This review highlights the roles of the inflammatory cyclooxygenase and 12/15-lipoxygenase pathways in the pathogenesis of diabetic vascular disease. Evidence suggests that inflammatory responses in the vasculature can be elicited by small oxidized lipids that are components of oxidized low-density lipoprotein or products of the lipoxygenase and cyclooxygenase pathways of arachidonic and linoleic acid metabolism. This review evaluates these inflammatory and proatherogenic pathways in the pathogenesis of diabetic vascular disease.
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Affiliation(s)
- Rama Natarajan
- Gonda Diabetes Research Center, Beckman Research Institute of City of Hope, 1500 East Duarte Road, Duarte, CA 91010, USA.
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191
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Solomon DH, Schneeweiss S, Glynn RJ, Kiyota Y, Levin R, Mogun H, Avorn J. Relationship Between Selective Cyclooxygenase-2 Inhibitors and Acute Myocardial Infarction in Older Adults. Circulation 2004; 109:2068-73. [PMID: 15096449 DOI: 10.1161/01.cir.0000127578.21885.3e] [Citation(s) in RCA: 324] [Impact Index Per Article: 15.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Background—
Although cyclooxygenase-2 inhibitors (coxibs) were developed to cause less gastrointestinal hemorrhage than nonselective nonsteroidal antiinflammatory drugs (NSAIDs), there has been concern about their cardiovascular safety. We studied the relative risk of acute myocardial infarction (AMI) among users of celecoxib, rofecoxib, and NSAIDs in Medicare beneficiaries with a comprehensive drug benefit.
Methods and Results—
We conducted a matched case-control study of 54 475 patients 65 years of age or older who received their medications through 2 state-sponsored pharmaceutical benefits programs in the United States. All healthcare use encounters were examined to identify hospitalizations for AMI. Each of the 10 895 cases of AMI was matched to 4 controls on the basis of age, gender, and the month of index date. We constructed matched logistic regression models including indicators for patient demographics, healthcare use, medication use, and cardiovascular risk factors to assess the relative risk of AMI in patients who used rofecoxib compared with persons taking no NSAID, taking celecoxib, or taking NSAIDs. Current use of rofecoxib was associated with an elevated relative risk of AMI compared with celecoxib (odds ratio [OR], 1.24; 95% CI, 1.05 to 1.46;
P
=0.011) and with no NSAID (OR, 1.14; 95% CI, 1.00 to 1.31;
P
=0.054). The adjusted relative risk of AMI was also elevated in dose-specific comparisons: rofecoxib ≤25 mg versus celecoxib ≤200 mg (OR, 1.21; 95% CI, 1.01 to 1.44;
P
=0.036) and rofecoxib >25 mg versus celecoxib >200 mg (OR, 1.70; 95% CI, 1.07 to 2.71;
P
=0.026). The adjusted relative risks of AMI associated with rofecoxib use of 1 to 30 days (OR, 1.40; 95% CI, 1.12 to 1.75;
P
=0.005) and 31 to 90 days (OR, 1.38; 95% CI, 1.11 to 1.72;
P
=0.003) were higher than >90 days (OR, 0.96; 95% CI, 0.72 to 1.25;
P
=0.8) compared with celecoxib use of similar duration. Celecoxib was not associated with an increased relative risk of AMI in these comparisons.
Conclusions—
In this study, current rofecoxib use was associated with an elevated relative risk of AMI compared with celecoxib use and no NSAID use. Dosages of rofecoxib >25 mg were associated with a higher risk than dosages ≤25 mg. The risk was elevated in the first 90 days of use but not thereafter.
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Affiliation(s)
- Daniel H Solomon
- Division of Pharmacoepidemiology and Pharmacoeconomics, Brigham and Women's Hospital, Harvard Medical School, 1620 Tremont St, Suite 3030, Boston, Mass 02120, USA.
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192
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Khan KMF, Howe LR, Falcone DJ. Extracellular Matrix-induced Cyclooxygenase-2 Regulates Macrophage Proteinase Expression. J Biol Chem 2004; 279:22039-46. [PMID: 15024003 DOI: 10.1074/jbc.m312735200] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Chronic inflammatory diseases are characterized by the persistent presence of macrophages and other mononuclear cells, tissue destruction, cell proliferation, and the deposition of extracellular matrix (ECM). The tissue degradation is mediated, in part, by enhanced proteinase expression by macrophages. It has been demonstrated recently that macrophage proteinase expression can be stimulated or inhibited by purified ECM components. However, in an intact ECM the biologically active domains of matrix components may be masked either by tertiary conformation or by complex association with other matrix molecules. In an effort to determine whether a complex ECM produced by vascular smooth muscle cells (SMC) regulates macrophage degradative phenotype, we prepared insoluble SMC matrices and examined their ability to regulate proteinase expression by RAW264.7 and thioglycollate-elicited peritoneal macrophages. Here we demonstrate that macrophage engagement of SMC-ECM triggers PKC-dependent activation of MAPK(erk1/2) leading to increased expression of cyclooxygenase (COX)-2 and prostaglandin (PG) E(2) synthesis. The addition of PGE(2) to macrophage cultures stimulates their expression of both urokinase-type plasminogen activator and MMP-9, and the selective COX-2 inhibitor NS-398 blocks ECM-induced proteinase expression. Moreover, ECM-induced PGE(2) and MMP-9 expression by elicited COX-2(-/-) macrophages is markedly reduced when compared with the response of either COX-2(+/-) or COX-2(+/+) macrophages. These data clearly demonstrate that SMC-ECM exerts a regulatory role on the degradative phenotype of macrophages via enhanced urokinase-type plasminogen activator and MMP-9 expression, and identify COX-2 as a targetable component of the signaling pathway leading to increased proteinase expression.
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Affiliation(s)
- K M Faisal Khan
- Department of Pathology and Laboratory Medicine, Joan and Sanford I. Weill Medical College, Cornell University, New York, New York 10021, USA
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193
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Cipollone F, Fazia M, Iezzi A, Pini B, Cuccurullo C, Zucchelli M, de Cesare D, Ucchino S, Spigonardo F, De Luca M, Muraro R, Bei R, Bucci M, Cuccurullo F, Mezzetti A. Blockade of the Angiotensin II Type 1 Receptor Stabilizes Atherosclerotic Plaques in Humans by Inhibiting Prostaglandin E
2
–Dependent Matrix Metalloproteinase Activity. Circulation 2004; 109:1482-8. [PMID: 15037537 DOI: 10.1161/01.cir.0000121735.52471.ac] [Citation(s) in RCA: 102] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Background—
Clinical trials have demonstrated that agents that inhibit the angiotensin II pathway confer benefit beyond the reduction of blood pressure alone. However, the molecular mechanism underlying this effect has yet to be investigated. Recently, we have demonstrated enhanced expression of inducible cyclooxygenase (COX) and prostaglandin (PG)E
2
-dependent synthase (COX-2/mPGES-1) in human symptomatic plaques and provided evidence that it is associated with metalloproteinase (MMP)-induced plaque rupture. Thus, the aim of this study was to characterize the effect of the angiotensin II type 1 (AT
1
) receptor antagonist irbesartan on the inflammatory infiltration and expression of COX-2/mPGES-1 and MMPs in human carotid plaques.
Methods and Results—
Seventy patients with symptomatic carotid artery stenosis were randomized to irbesartan (300 mg/d) or chlorthalidone (50 mg/d) for 4 months before endarterectomy. Plaques were subjected to analysis of COX-1, COX-2, mPGES-1, MMP-2, and MMP-9, angiotensin II, AT
1
, AT
2
, and collagen content by immunocytochemistry, Western blot, and reverse-transcriptase polymerase chain reaction, whereas zymography was used to detect MMP activity. Immunohistochemistry was also used to identify CD68+ macrophages, CD3+ T lymphocytes, smooth muscle cells (SMCs), and HLA-DR+ inflammatory cells. Plaques from the irbesartan group had fewer (
P
<0.0001) macrophages, T lymphocytes, and HLA-DR+ cells; less (
P
<0.0001) immunoreactivity for COX-2/mPGES-1 and MMPs; reduced (
P
<0.0001) gelatinolytic activity; and increased (
P
<0.0001) collagen content. It is worth noting that COX-2/mPGES-1 inhibition was observed after incubation in vitro with irbesartan but not with the selective AT
2
blockade PD123,319.
Conclusions—
This study demonstrates that irbesartan decreases inflammation and inhibits COX-2/mPGES-1 expression in plaque macrophages, and this effect may in turn contribute to plaque stabilization by inhibition of MMP-induced plaque rupture.
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Affiliation(s)
- Francesco Cipollone
- G. d'Annunzio University of Chieti and the G. d'Annunzio University Foundation, Chieti, Italy
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194
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Fazio S, Linton MF. The role of fibrates in managing hyperlipidemia: Mechanisms of action and clinical efficacy. Curr Atheroscler Rep 2004; 6:148-57. [PMID: 15023300 DOI: 10.1007/s11883-004-0104-8] [Citation(s) in RCA: 91] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
At a time when the lipid management guidelines give more and more emphasis to the identification and treatment of high-risk patients with the metabolic syndrome and diabetes, there is an obvious need to balance the known effects of low-density lipoprotein (LDL) lowering with the new evidence of clinical efficacy derived from the adjustment of high-density lipoprotein (HDL) and triglyceride levels. Whereas the statins remain the drug of choice for patients who need to reach the LDL goal, fibrate therapy may represent the best intervention for subjects with atherogenic dyslipidemia and an LDL already close to goal. In addition, the concomitant use of fibrates may significantly reduce cardiovascular risk in patients whose LDL is controlled by statin therapy. In this review, we evaluate the pharmacologic properties of the fibrate drugs, with particular attention to the effects of peroxisome proliferator activated receptor a activation in the control of dyslipidemia as well as in the attenuation of arterial inflammation. Clinical trials of fibrates, such as the Helsinki Heart Study, Veterans Affairs High-density lipoprotein Intervention Trial, Diabetes Atherosclerosis Intervention Study, and Bezafibrate Infarction Prevention trial, have conjured up a scenario for the clinical utility of fibrates and their possible superiority to statins in the management of obese, insulin-resistant, and diabetic patients presenting with near-goal LDL and inappropriate HDL and triglyceride levels.
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Affiliation(s)
- Sergio Fazio
- Division of Cardiovascular Medicine, Vanderbilt University Medical Center, 383 PRB, Nashville, TN 37232-6300, USA.
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195
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Shanmugam N, Gaw Gonzalo IT, Natarajan R. Molecular mechanisms of high glucose-induced cyclooxygenase-2 expression in monocytes. Diabetes 2004; 53:795-802. [PMID: 14988266 DOI: 10.2337/diabetes.53.3.795] [Citation(s) in RCA: 84] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
The cyclooxygenase (COX)-2 enzyme has been implicated in the pathogenesis of several inflammatory diseases. However, its role in diabetic vascular disease is unclear. In this study, we evaluated the hypothesis that diabetic conditions can induce COX-2 in monocytes. High glucose treatment of THP-1 monocytic cells led to a significant three- to fivefold induction of COX-2 mRNA and protein expression but not COX-1 mRNA. High glucose-induced COX-2 mRNA was blocked by inhibitors of nuclear factor-kappaB (NF-kappaB), protein kinase C, and p38 mitogen-activated protein kinase. In addition, an antioxidant and inhibitors of mitochondrial superoxide, NADPH oxidase, and glucose metabolism to glucosamine also blocked high glucose-induced COX-2 expression to varying degrees. High glucose significantly increased transcription from a human COX-2 promoter-luciferase construct (twofold, P < 0.001). Promoter deletion analyses and inhibition of transcription by NF-kappaB superrepressor and cAMP-responsive element binding (CREB) mutants confirmed the involvement of NF-kappaB and CREB transcription factors in high glucose-induced COX-2 regulation. In addition, isolated peripheral blood monocytes from type 1 and type 2 diabetic patients had high levels of COX-2 mRNA, whereas those from normal volunteers showed no expression. These results show that high glucose and diabetes can augment inflammatory responses by upregulating COX-2 via multiple signaling pathways, leading to monocyte activation relevant to the pathogenesis of diabetes complications.
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Affiliation(s)
- Narkunaraja Shanmugam
- Gonda Diabetes Research Center, Beckman Research Institute of the City of Hope, Duarte, California, USA
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196
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Cipollone F, Rocca B, Patrono C. Cyclooxygenase-2 Expression and Inhibition in Atherothrombosis. Arterioscler Thromb Vasc Biol 2004; 24:246-55. [PMID: 14592854 DOI: 10.1161/01.atv.0000104005.92603.f2] [Citation(s) in RCA: 90] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Arachidonic acid metabolism plays an important role in acute ischemic syndromes affecting the coronary or cerebrovascular territory, as reflected by biochemical measurements of eicosanoid biosynthesis and the results of inhibitor trials in these settings. Two cyclooxygenase (COX)-isozymes have been characterized, COX-1 and COX-2, that differ in terms of regulatory mechanisms of expression, tissue distribution, substrate specificity, preferential coupling to upstream and downstream enzymes, and susceptibility to inhibition by the extremely heterogeneous class of COX-inhibitors. Although the role of platelet COX-1 in acute coronary syndromes and ischemic stroke is firmly established through ≈20 years of thromboxane metabolite measurements and aspirin trials, the role of COX-2 expression and inhibition in atherothrombosis is substantially uncertain, because the enzyme was first characterized in 1991 and selective COX-2 inhibitors became commercially available only in 1998. In this review, we discuss the pattern of expression of COX-2 in the cellular players of atherothrombosis, its role as a determinant of plaque “vulnerability,” and the clinical consequences of COX-2 inhibition. Recent studies from our group suggest that variable expression of upstream and downstream enzymes in the prostanoid biosynthetic cascade may represent important determinants of the functional consequences of COX-2 expression and inhibition in different clinical settings.
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Affiliation(s)
- Francesco Cipollone
- Center of Excellence on Aging, G. D'Annunzio University of Chieti School of Medicine, Chieti, Italy
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197
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Sussmann M, Sarbia M, Meyer-Kirchrath J, Nüsing RM, Schrör K, Fischer JW. Induction of hyaluronic acid synthase 2 (HAS2) in human vascular smooth muscle cells by vasodilatory prostaglandins. Circ Res 2004; 94:592-600. [PMID: 14752026 DOI: 10.1161/01.res.0000119169.87429.a0] [Citation(s) in RCA: 60] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Hyaluronic acid (HA) is a prominent constituent of the extracellular matrix of atherosclerotic vascular lesions in humans known to modulate vascular smooth muscle phenotype. The regulation of HA synthesis by vasodilatory prostaglandins was analyzed in human arterial smooth muscle cells (SMCs). The prostacyclin analogue, iloprost (100 nmol/L), markedly increased pericellular formation of HA coats and HA secretion into the cell culture medium in human arterial SMCs (8.7+/-1.6-fold). Expression of HA synthase 2 (HAS2) was determined by semiquantitative RT-PCR and found to be strongly upregulated at concentrations of iloprost between 1 and 100 nmol/L after 3 hours. Furthermore, endogenous cyclooxygenase-2 (COX2) activity was required for basal expression of HAS2 mRNA in SMCs in vitro. Total HA secretion in response to iloprost was markedly decreased by RNA interference (RNAi), specific for HAS2. In addition, siRNA targeting HAS2 strongly increased the spreading of human SMCs compared with mock-transfected cells. HAS2 mRNA levels were also stimulated by a selective prostacyclin receptor (IP) agonist, cicaprost (10 nmol/L), prostaglandin E(2) (10 nmol/L), and the EP(2) receptor agonist, butaprost (1 micromol/L). Induction of HAS2 mRNA and HA synthesis by prostaglandins was mimicked by stable cAMP analogues and forskolin. In human atherectomy specimens from the internal carotid artery, HA deposits and COX2 expression colocalized frequently. In addition, strong EP(2) receptor expression was detected in SMCs in HA-rich areas. Therefore, upregulation of HAS2 expression via EP(2) and IP receptors might contribute to the accumulation of HA during human atherosclerosis, thereby mediating proatherosclerotic functions of COX2.
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MESH Headings
- 6-Ketoprostaglandin F1 alpha/biosynthesis
- Acetophenones/pharmacology
- Alprostadil/analogs & derivatives
- Alprostadil/pharmacology
- Arteriosclerosis/metabolism
- Arteriosclerosis/pathology
- Becaplermin
- Benzopyrans/pharmacology
- Bucladesine/pharmacology
- Carotid Artery Diseases/pathology
- Carotid Artery, Internal/pathology
- Cells, Cultured/drug effects
- Cells, Cultured/metabolism
- Colforsin/pharmacology
- Cyclic AMP/physiology
- Cyclooxygenase 2
- Enzyme Induction/drug effects
- Epoprostenol/analogs & derivatives
- Epoprostenol/pharmacology
- Extracellular Matrix/metabolism
- Glucuronosyltransferase/biosynthesis
- Glucuronosyltransferase/genetics
- Humans
- Hyaluronan Synthases
- Hyaluronic Acid/biosynthesis
- Hyaluronic Acid/metabolism
- Iloprost/pharmacology
- Indoles/pharmacology
- Isoenzymes/physiology
- Isoquinolines/pharmacology
- Macrophages/metabolism
- Maleimides/pharmacology
- Membrane Proteins
- Muscle Cells/drug effects
- Muscle Cells/metabolism
- Muscle, Smooth, Vascular/drug effects
- Muscle, Smooth, Vascular/metabolism
- Pertussis Toxin/pharmacology
- Platelet-Derived Growth Factor/pharmacology
- Prostaglandin-Endoperoxide Synthases/physiology
- Proto-Oncogene Proteins c-sis
- RNA, Messenger/biosynthesis
- RNA, Small Interfering/pharmacology
- Receptors, Prostaglandin E/drug effects
- Receptors, Prostaglandin E, EP2 Subtype
- Sulfonamides
- Vasodilator Agents/pharmacology
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Affiliation(s)
- M Sussmann
- Institut für Pharmakologie und Klinische Pharmakologie, Heinrich Heine Universität Düsseldorf, Germany
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198
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FitzGerald GA. COX-2 and beyond: Approaches to prostaglandin inhibition in human disease. Nat Rev Drug Discov 2004; 2:879-90. [PMID: 14668809 DOI: 10.1038/nrd1225] [Citation(s) in RCA: 346] [Impact Index Per Article: 16.5] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Affiliation(s)
- Garret A FitzGerald
- Center for Experimental Therapeutics, University of Pennsylvania, Philadelphia, Pennsylvania 19104, USA.
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199
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Dwyer JH, Allayee H, Dwyer KM, Fan J, Wu H, Mar R, Lusis AJ, Mehrabian M. Arachidonate 5-lipoxygenase promoter genotype, dietary arachidonic acid, and atherosclerosis. N Engl J Med 2004; 350:29-37. [PMID: 14702425 DOI: 10.1056/nejmoa025079] [Citation(s) in RCA: 417] [Impact Index Per Article: 19.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
BACKGROUND Leukotrienes are inflammatory mediators generated from arachidonic acid (polyunsaturated n-6 fatty acid) by the enzyme 5-lipoxygenase. Since atherosclerosis involves arterial inflammation, we hypothesized that a polymorphism in the 5-lipoxygenase gene promoter could relate to atherosclerosis in humans and that this effect could interact with the dietary intake of competing 5-lipoxygenase substrates. METHODS We determined 5-lipoxygenase genotypes, carotid-artery intima-media thickness, and markers of inflammation in a randomly sampled cohort of 470 healthy, middle-aged women and men from the Los Angeles Atherosclerosis Study. Dietary arachidonic acid and marine n-3 fatty acids (including a competing 5-lipoxygenase substrate that reduces the production of inflammatory leukotrienes) were measured with the use of six 24-hour recalls of food intake. RESULTS Variant 5-lipoxygenase genotypes (lacking the common allele) were found in 6.0 percent of the cohort. Mean (+/-SE) intima-media thickness adjusted for age, sex, height, and racial or ethnic group was increased by 80+/-19 microm (95 percent confidence interval, 43 to 116; P<0.001) among carriers of two variant alleles, as compared with carriers of the common (wild-type) allele. In multivariate analysis, the increase in intima-media thickness among carriers of two variant alleles (62 microm, P<0.001) was similar in this cohort to that associated with diabetes (64 microm, P=0.01), the strongest common cardiovascular risk factor. Increased dietary arachidonic acid significantly enhanced the apparent atherogenic effect of genotype, whereas increased dietary intake of n-3 fatty acids blunted the effect. Finally, the plasma level of C-reactive protein, a marker of inflammation, was increased by a factor of 2 among carriers of two variant alleles as compared with that among carriers of the common allele. CONCLUSIONS Variant 5-lipoxygenase genotypes identify a subpopulation with increased atherosclerosis. The observed diet-gene interactions further suggest that dietary n-6 polyunsaturated fatty acids promote, whereas marine n-3 fatty acids inhibit, leukotriene-mediated inflammation that leads to atherosclerosis in this subpopulation.
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Affiliation(s)
- James H Dwyer
- Department of Preventive Medicine, Keck School of Medicine, University of Southern California, CA 91803-8000, USA.
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200
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Belton OA, Duffy A, Toomey S, Fitzgerald DJ. Cyclooxygenase Isoforms and Platelet Vessel Wall Interactions in the Apolipoprotein E Knockout Mouse Model of Atherosclerosis. Circulation 2003; 108:3017-23. [PMID: 14638539 DOI: 10.1161/01.cir.0000104565.78013.ad] [Citation(s) in RCA: 100] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Background—
Cyclooxygenase (COX) activity is induced in human atherosclerosis, and the products formed may modify the disease directly or through an effect on platelets. We examined the role of COX-1 and -2 on platelet vessel wall interactions and development of atherosclerosis in a murine model.
Methods and Results—
Apolipoprotein E–deficient (apoE
−/−
) mice fed a 1% cholesterol diet were treated with a selective COX-1 inhibitor (SC-560), a selective COX-2 inhibitor (SC-236), or vehicle. Urinary prostacyclin and thromboxane metabolites (2,3-dinor-6-keto-PGF
1α
and 2,3-dinor-TXB
2
) were increased in the apoE
−/−
knockout mouse. There was also induction of both COX isoforms in the vascular lesions formed, which stained for CD41, a platelet-specific marker, and for CD40L. Selective inhibition of COX-2 had no effect on lesion formation and, despite selective reduction in prostacyclin generation, had no effect on platelet activity, as measured by thromboxane formation or platelet deposition. Selective inhibition of COX-1 reduced 2,3-dinor-TXB
2
generation and lesion formation. However, platelet deposition on the vessel wall persisted, with well-defined monolayers seen. There was also persistent expression of the macrophage marker CD68 and increased expression of the cell death protein Bax. In contrast to lesion development, the selective COX-1 inhibitor had no effect on the regression of evolving lesions.
Conclusions—
COX-1 plays an important role in the early stages of lesion development in the apoE
−/−
knockout model of atherosclerosis, preventing gross lesion formation in the face of continued vascular injury and inflammation. Despite the inhibition of prostacyclin, COX-2 inhibition had no effect on lesion development or platelet–vessel wall interactions.
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Affiliation(s)
- Orina A Belton
- Department of Clinical Pharmacology and Institute of Biopharmaceutical Sciences, Royal College of Surgeons in Ireland 123, St Stephens Green, Dublin 2, Ireland.
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