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Zhang H, Chen S, Deng X, Yang X, Huang X. Danggui-Buxue-Tang decoction has an anti-inflammatory effect in diabetic atherosclerosis rat model. Diabetes Res Clin Pract 2006; 74:194-6. [PMID: 16713007 DOI: 10.1016/j.diabres.2006.04.003] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/05/2006] [Accepted: 04/06/2006] [Indexed: 11/19/2022]
Abstract
Danggui-Buxue-Tang (DBT) is a famous traditional Chinese formula. We examined the anti-inflammatory effect of it in diabetic atherosclerosis rats. DBT (3 or 6g/kg/day for 4 weeks) was orally administrated to the diabetic atherosclerosis rats, which were induced by nitric oxide inhibition (l-NAME in drinking water, 1mg/ml) plus high-fat diet. The concentrations of circulating inflammatory markers C-reactive protein (CRP) and tumour necrosis factor-alpha (TNF-alpha) and serum fructosamine were determined. The results showed that DBT had no direct effect in lowering serum fructosamine level, but can decrease the concentrations of CRP and TNF-alpha, produce a higher survival rate and less body weight loss, and decrease water intake in diabetic atherosclerosis in GK rats.
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Affiliation(s)
- Hongmin Zhang
- Laboratory of Ethnopharmacology, West China Hospital, Sichuan University, Chengdu 610041, PR China
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Tsuchiya K, Yoshimoto T, Hirono Y, Tateno T, Sugiyama T, Hirata Y. Angiotensin II induces monocyte chemoattractant protein-1 expression via a nuclear factor-kappaB-dependent pathway in rat preadipocytes. Am J Physiol Endocrinol Metab 2006; 291:E771-8. [PMID: 16705055 DOI: 10.1152/ajpendo.00560.2005] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Both monocyte chemoattractant protein-1 (MCP-1), a member of chemokine family, and angiotensinogen, a precursor of angiotensin (ANG) II, are produced by adipose tissue and increased in obese state. MCP-1 has been shown to decrease insulin-stimulated glucose uptake and several adipogenic genes expression in adipocytes in vitro, suggesting its pathophysiological significance in obesity. However, the pathophysiological interaction between MCP-1 and ANG II in adipose tissue remains unknown. The present study was undertaken to investigate the potential mechanisms by which ANG II affects MCP-1 gene expression in rat primary cultured preadipocytes and adipose tissue in vivo. ANG II significantly increased steady-state MCP-1 mRNA levels in a time- and dose-dependent manner. The ANG II-induced MCP-1 mRNA and protein expression was completely abolished by ANG II type 1 (AT1)-receptor antagonist (valsartan). An antioxidant/NF-kappaB inhibitor (pyrrolidine dithiocarbamate) and an inhibitor of 1kappaB-alpha phosphorylation (Bay 11-7085) also blocked ANG II-induced MCP-1 mRNA expression. ANG II induced translocation of NF-kappaB p65 subunit from cytoplasm to nucleus by immunocytochemical study. Luciferase assay using reporter constructs containing MCP-1 promoter region revealed that two NF-kappaB binding sites in its enhancer region were essential for the ANG II-induced promoter activities. Furthermore, basal mRNA and protein of MCP-1 during preadipocyte differentiation were significantly greater in preadipocytes than in differentiated adipocytes, whose effect was more pronounced in the presence of ANG II. Exogenous administration of ANG II to rats led to increased MCP-1 expression in epididymal, subcutaneous, and mesenteric adipose tissue. In conclusion, our present study demonstrates that ANG II increases MCP-1 gene expression via ANG II type 1 receptor-mediated and NF-kappaB-dependent pathway in rat preadipocytes as well as adipose MCP-1 expression in vivo. Thus the augmented MCP-1 expression by ANG II in preadipocytes may provide a new link between obesity and cardiovascular disease.
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Affiliation(s)
- Kyoichiro Tsuchiya
- Department of Clinical and Molecular Endocrinology, Tokyo Medical and Dental University Graduate School, 1-5-45 Yushima, Bunkyo-ku, Tokyo 113-8513, Japan
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Igarashi M, Hirata A, Kadomoto Y, Tominaga M. Dual blockade of angiotensin II with enalapril and losartan reduces proteinuria in hypertensive patients with type 2 diabetes. Endocr J 2006; 53:493-501. [PMID: 16829707 DOI: 10.1507/endocrj.k06-025] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
In this study we evaluated the effect of a dual blockade with enalapril and losartan on the reduction of overt macroproteinuria and its potential mechanism(s) in hypertensive patients with type 2 diabetes. Twenty-six hypertensive patients with type 2 diabetes at the baseline were administered 5 mg of enalapril once daily for 12 weeks. At the beginning of the study, the subjects were assigned to receive an add-on of 50 mg of losartan once daily or 5 mg of enalapril once daily for another 12 weeks. Blood samples were collected at the baseline, at the beginning, and at the end of the study for the measurement of laboratory parameters, and these data, including blood pressure, were compared between the two groups. Treatment with 5 mg of enalapril significantly decreased the systolic blood pressure level in both groups, and the addition of losartan and/or enalapril further decreased the levels. There was no difference in blood pressure between the two groups. However, the addition of losartan, but not enalapril, significantly decreased the urinary protein excretion level, plasma aldosterone, and hypersensitive-C-reactive protein at the end of the study. The results established that the dual blockade of angiotensin II with enalapril and losartan has a greater clinical benefit for high-risk patients with hypertension and advanced diabetic nephropathy.
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Affiliation(s)
- Masahiko Igarashi
- Department of Laboratory Medicine, Yamagata University School of Medicine, Yamagata, Japan
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Saavedra JM, Benicky J, Zhou J. Mechanisms of the Anti-Ischemic Effect of Angiotensin II AT( 1 ) Receptor Antagonists in the Brain. Cell Mol Neurobiol 2006; 26:1099-111. [PMID: 16636899 DOI: 10.1007/s10571-006-9009-0] [Citation(s) in RCA: 61] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2005] [Accepted: 01/09/2006] [Indexed: 01/23/2023]
Abstract
1. Circulating and locally formed Angiotensin II regulates the cerebral circulation through stimulation of AT(1) receptors located in cerebrovascular endothelial cells and in brain centers controlling cerebrovascular flow. 2. The cerebrovascular autoregulation is designed to maintain a constant blood flow to the brain, by vasodilatation when blood pressure decreases and vasoconstriction when blood pressure increases. 3. During hypertension, there is a shift in the cerebrovascular autoregulation to the right, in the direction of higher blood pressures, as a consequence of decreased cerebrovascular compliance resulting from vasoconstriction and pathological growth. In hypertension, when perfusion pressure decreases as a consequence of blockade of a cerebral artery, reduced cerebrovascular compliance results in more frequent and more severe strokes with a larger area of injured tissue. 4. There is a cerebrovascular angiotensinergic overdrive in genetically hypertensive rats, manifested as an increased expression of cerebrovascular AT(1) receptors and increased activity of the brain Angiotensin II system. Excess AT(1) receptor stimulation is a main factor in the cerebrovascular pathological growth and decreased compliance, the alteration of the cerebrovascular eNOS/iNOS ratio, and in the inflammatory reaction characteristic of cerebral blood vessels in genetic hypertension. All these factors increase vulnerability to brain ischemia and stroke. 5. Sustained blockade of AT(1) receptors with peripheral and centrally active AT(1) receptor antagonists (ARBs) reverses the cerebrovascular pathological growth and inflammation, increases cerebrovascular compliance, restores the eNOS/iNOS ratio and decreases cerebrovascular inflammation. These effects result in a reduction of the vulnerability to brain ischemia, revealed, when an experimental stroke is produced, in protection of the blood flow in the zone of penumbra and substantial reduction in neuronal injury. 6. The protection against ischemia resulting is related to inhibition of the Renin-Angiotensin System and not directly related to the decrease in blood pressure produced by these compounds. A similar decrease in blood pressure as a result of the administration of beta-adrenergic receptor and calcium channel blockers does not protect from brain ischemia. 7. In addition, sustained AT(1) receptor inhibition enhances AT(2) receptor expression, associated with increased eNOS activity and NO formation followed by enhanced vasodilatation. Direct AT(1) inhibition and indirect AT(2) receptor stimulation are associated factors normalizing cerebrovascular compliance, reducing cerebrovascular inflammation and decreasing the vulnerability to brain ischemia.8. These results strongly suggest that inhibition of AT(1) receptors should be considered as a preventive therapeutic measure to protect the brain from ischemia, and as a possible novel therapy of inflammatory conditions of the brain.
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Affiliation(s)
- Juan M Saavedra
- Section on Pharmacology, Division of Intramural Research Programs, National Institute of Mental Health, National Institutes of Health, Department of Health and Human Services, Bethesda, Maryland, USA.
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Benter IF, Yousif MHM, Anim JT, Cojocel C, Diz DI. Angiotensin-(1-7) prevents development of severe hypertension and end-organ damage in spontaneously hypertensive rats treated with L-NAME. Am J Physiol Heart Circ Physiol 2006; 290:H684-91. [PMID: 16403946 DOI: 10.1152/ajpheart.00632.2005] [Citation(s) in RCA: 144] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
We examined the influence of chronic treatment with ANG-(1-7) on development of hypertension and end-organ damage in spontaneously hypertensive rats (SHR) chronically treated with the nitric oxide synthesis inhibitor L-NAME (SHR-L-NAME). L-NAME administered orally (80 mg/l) for 4 wk significantly elevated mean arterial pressure (MAP) compared with SHR controls drinking regular water (269 +/- 10 vs. 196 +/- 6 mmHg). ANG-(1-7) (24 microg x kg(-1) x h(-1)) or captopril (300 mg/l) significantly attenuated the elevation in MAP due to L-NAME (213 +/- 7 and 228 +/- 8 mmHg, respectively), and ANG-(1-7) + captopril completely reversed the L-NAME-dependent increase in MAP (193 +/- 5 mmHg). L-NAME-induced increases in urinary protein were significantly lower in ANG-(1-7)-treated animals (226 +/- 6 vs. 145 +/- 12 mg/day). Captopril was more effective (96 +/- 12 mg/day), and there was no additional effect of captopril + ANG-(1-7) (87 +/- 5 mg/day). The abnormal vascular responsiveness to endothelin-1, carbachol, and sodium nitroprusside in perfused mesenteric vascular bed of SHR-L-NAME was improved by ANG-(1-7) or captopril, with no additive effect of ANG-(1-7) + captopril. In isolated perfused hearts, recovery of left ventricular function from 40 min of global ischemia was significantly better in ANG-(1-7)- or captopril-treated SHR-L-NAME, with additive effects of combined treatment. The beneficial effects of ANG-(1-7) on MAP and cardiac function were inhibited when indomethacin was administered with ANG-(1-7), but indomethacin did not reverse the protective effects on proteinuria or vascular reactivity. The protective effects of the ANG-(1-7) analog AVE-0991 were qualitatively comparable to those of ANG-(1-7) but were not improved over those of captopril alone. Thus, during reduced nitric oxide availability, ANG-(1-7) attenuates development of severe hypertension and end-organ damage; prostaglandins participate in the MAP-lowering and cardioprotective effects of ANG-(1-7); and additive effects of captopril + ANG-(1-7) on MAP, but not proteinuria or endothelial function, suggest common, as well as different, mechanisms of action for the two treatments. Together, the results provide further evidence of a role for ANG-(1-7) in protective effects of angiotensin-converting enzyme inhibition and suggest dissociation of factors influencing MAP and those influencing end-organ damage.
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Affiliation(s)
- Ibrahim F Benter
- Dept. of Pharmacology and Toxicology, Faculty of Medicine, Kuwait Univ., PO Box 24923, Safat 13110, Kuwait.
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Müller AM, Maas M, Kozianka U, Franke FE. [Expression of angiotensin I converting enzyme in pulmonary hypertension]. DER PATHOLOGE 2006; 27:133-9. [PMID: 16453109 DOI: 10.1007/s00292-006-0820-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
We studied angiotensin I converting enzyme (ACE) expression in lung tissue from patients with different forms of pulmonary hypertension (PH) in comparison with that from morphologically normal lung specimens. ACE antigen expression was analysed by immunohistochemistry in morphologically normal lung tissue from 33 patients (19 males, 32-77 years; 14 females, 34-93 years) and compared to that in specimens from 94 patients (67 males, 30-97 years; 27 females: 27-90 years) with different clinically proven forms of PH (according to Venedig classification). Type specific vessel expression pattern as described for normal lung tissue was generally intensified in arteries, arterioles and capillaries of the lung specimens with PH. Specimens with PH due to left heart disease and chronic obstructive pulmonary disease (COPD) showed only very weak or no augmented arterial ACE expression, while PH due to collagenoses or interstitial lung disease showed significantly higher ACE expression. In human PH there is--comparable to animal models--a raised ACE expression in pulmonary lung vessels, with differences between the various forms of PH. These differences in ACE expression may be relevant for subtly differentiated therapeutic anti-ACE therapy regimes.
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Affiliation(s)
- A M Müller
- Institut für Pathologie der Ruhr-Universität Bochum, Berufsgenossenschaftliche Kliniken Bergmannsheil, Bochum.
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Zicha J, Dobesová Z, Kunes J. Antihypertensive Mechanisms of Chronic Captopril or N-Acetylcysteine Treatment in L-NAME Hypertensive Rats. Hypertens Res 2006; 29:1021-7. [PMID: 17378375 DOI: 10.1291/hypres.29.1021] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Hypertension due to chronic inhibition of NO synthase (NOS) by Nomega-nitro-L-arginine methyl ester (L-NAME) administration is characterized by both impaired NO-dependent vasodilation and enhanced sympathetic vasoconstriction. The aim of our study was to evaluate changes in the participation of major vasoactive systems in L-NAME-treated rats which were subjected to simultaneous antihypertensive (captopril) or antioxidant (N-acetylcysteine, NAC) treatment. Three-month-old Wistar males treated with L-NAME (60 mg/kg/day) for 5 weeks were compared to rats in which L-NAME treatment was combined with simultaneous chronic administration of captopril or NAC. Basal blood pressure (BP) and its acute responses to consecutive i.v. injections of captopril (10 mg/kg), pentolinium (5 mg/kg), L-NAME (30 mg/kg), tetraethylammonium (TEA, 16 mg/kg) and nitroprusside (NP, 20 microg/kg) were determined in conscious rats at the end of the study. The development of L-NAME hypertension was prevented by captopril treatment, whereas NAC treatment caused only a moderate BP reduction. Captopril treatment normalized the sympathetic BP component and significantly reduced residual BP (measured at full NP-induced vasodilation). In contrast, chronic NAC treatment did not modify the sympathetic BP component or residual BP, but significantly enhanced NO-dependent vasodilation. Neither captopril nor NAC treatment influenced the compensatory increase of TEA-sensitive vasodilation mediated by endothelium-derived hyperpolarizing factor in L-NAME-treated rats. Chronic captopril treatment prevented L-NAME hypertension by lowering of sympathetic tone, whereas chronic NAC treatment attenuated L-NAME hypertension by reduction in the vasodilator deficit due to enhanced NO-dependent vasodilation.
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Affiliation(s)
- Josef Zicha
- Institute of Physiology AS CR and Cardiovascular Research Center, Prague, Czech Republic.
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Wu L, Iwai M, Li Z, Li JM, Mogi M, Horiuchi M. Nifedipine inhibited angiotensin II-induced monocyte chemoattractant protein 1 expression: involvement of inhibitor of nuclear factor kappa B kinase and nuclear factor kappa B-inducing kinase. J Hypertens 2006; 24:123-30. [PMID: 16331110 DOI: 10.1097/01.hjh.0000198031.30095.d1] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
OBJECTIVE The effect of nifedipine, a 1,4-dihydropyridine calcium antagonist, on the expression of monocyte chemoattractant protein 1 (MCP-1) induced by angiotensin II (Ang II) was examined using vascular smooth muscle cells (VSMC) isolated from rat thoracic aorta. METHODS AND RESULTS Ang II increased the expression of MCP-1 messenger RNA accompanied by an increase in nuclear factor kappa B (NF-kappaB) binding activity to the cis DNA element in the promoter region of MCP-1. Ang II also decreased the cytosolic level of the inhibitor of NF-kappaB (IkappaB) and increased the phosphorylation of IkappaB subunits, IkappaBalpha and IkappaBbeta, as well as the phosphorylation of IkappaB kinase (IKK) subunits, IKKalpha and IKKbeta, suggesting that Ang II enhanced the breakdown of IkappaB. Nifedipine decreased MCP-1 mRNA expression, together with NF-kappaB binding activity to the promoter region of MCP-1 induced by Ang II. Nifedipine also attenuated the decrease in the cytosolic level of IkappaB, and the phosphorylation of IkappaB and IKK subunits induced by Ang II. Moreover, Ang II increased the phosphorylation of NF-kappaB-inducing kinase (NIK), and this increase was significantly inhibited by nifedipine. CONCLUSION As NIK is reported to activate IKK, our results suggest that nifedipine attenuates the effect of Ang II on MCP-1 expression in VSMC by regulating the activity of NF-kappaB through NIK, IKK and IkappaB.
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MESH Headings
- Angiotensin II/pharmacology
- Animals
- Aorta, Thoracic/cytology
- Blotting, Northern
- Blotting, Western
- Cells, Cultured
- Chemokine CCL2/biosynthesis
- Chemokine CCL2/genetics
- Gene Expression Regulation/drug effects
- Gene Expression Regulation/physiology
- I-kappa B Kinase/metabolism
- Male
- Muscle, Smooth, Vascular/cytology
- Muscle, Smooth, Vascular/drug effects
- Muscle, Smooth, Vascular/metabolism
- Nifedipine/pharmacology
- Promoter Regions, Genetic
- Protein Serine-Threonine Kinases/antagonists & inhibitors
- Protein Serine-Threonine Kinases/metabolism
- RNA, Messenger/metabolism
- Rats
- Rats, Sprague-Dawley
- Receptor, Angiotensin, Type 1/drug effects
- Receptor, Angiotensin, Type 1/physiology
- Reverse Transcriptase Polymerase Chain Reaction
- NF-kappaB-Inducing Kinase
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Affiliation(s)
- Lan Wu
- Department of Molecular and Cellular Biology, Division of Medical Biochemistry and Cardiovascular Biology, Ehime University School of Medicine, Shitsukawa, Tohon, Ehime 791-0295, Japan
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Sadamatsu K, Shimokawa H, Tashiro H, Seto T, Kakizoe H, Yamamoto K. Different effects of simvastatin and losartan on cytokine levels in coronary artery disease. Am J Cardiovasc Drugs 2006; 6:169-75. [PMID: 16780390 DOI: 10.2165/00129784-200606030-00004] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
BACKGROUND AND OBJECTIVE Use of HMG-CoA reductase inhibitors (statins) and angiotensin II type 1 (AT(1)) receptor antagonists reduces the incidence of cardiovascular events. The cytokines macrophage colony-stimulating factor (M-CSF) and transforming growth factor (TGF)-beta may exert proatherogenic and antiatherogenic effects, respectively. In this study, we examined whether treatment with a statin or an AT(1) receptor antagonist alters M-CSF and TGF-beta levels in patients with coronary artery disease. METHODS Twenty-seven consecutive patients with coronary artery disease were randomly assigned to the following three treatment groups for 8 weeks: simvastatin 5 mg/day (n = 10); losartan 50 mg/day (n = 9); or control (usual treatment; n = 8). Blood samples were collected before and after treatment. RESULTS Clinical characteristics and baseline cytokine levels were comparable among the three groups. Serum levels of M-CSF were significantly decreased only in the simvastatin group (from 403 +/- 71 to 303 +/- 116 pg/mL; p = 0.009). Plasma levels of TGF-beta were significantly increased only in the losartan group (from 5.01 +/- 1.13 to 7.50 +/- 3.83 ng/mL; p = 0.021). Simvastatin decreased serum M-CSF levels independently of changes in total cholesterol or low-density lipoprotein-cholesterol. CONCLUSIONS The results of this study indicate that simvastatin decreases serum levels of M-CSF while losartan increases plasma levels of TGF-beta, suggesting that the two drugs may have different anti-atherosclerotic properties.
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Affiliation(s)
- Kenji Sadamatsu
- Department of Cardiology, St Mary's Hospital, Kurume, Japan.
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Zhan Y, Brown C, Maynard E, Anshelevich A, Ni W, Ho IC, Oettgen P. Ets-1 is a critical regulator of Ang II-mediated vascular inflammation and remodeling. J Clin Invest 2005; 115:2508-16. [PMID: 16138193 PMCID: PMC1193876 DOI: 10.1172/jci24403] [Citation(s) in RCA: 176] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2005] [Accepted: 06/14/2005] [Indexed: 12/24/2022] Open
Abstract
Ang II is a central mediator of vascular inflammation and remodeling. The transcription factor Ets-1 is rapidly induced in vascular smooth muscle and endothelial cells of the mouse thoracic aorta in response to systemic Ang II infusion. Arterial wall thickening, perivascular fibrosis, and cardiac hypertrophy are significantly diminished in Ets1-/- mice compared with control mice in response to Ang II. The induction of 2 known targets of Ets-1, cyclin-dependent kinase inhibitor p21CIP and plasminogen activator inhibitor-1 (PAI-1), by Ang II is markedly blunted in the aorta of Ets1-/- mice compared with wild-type controls. Expression of p21CIP in VSMCs leads to cellular hypertrophy, whereas expression of p21CIP in endothelial cells is associated with cell cycle arrest, apoptosis, and endothelial dysfunction. PAI-1 promotes the development of perivascular fibrosis. We have identified monocyte chemoattractant protein-1 (MCP-1) as a novel target for Ets-1. Expression of MCP-1 is similarly reduced in Ets1-/- mice compared with control mice in response to Ang II, which results in significantly diminished recruitment of T cells and macrophages to the vessel wall. In summary, our results support a critical role for Ets-1 as a transcriptional mediator of vascular inflammation and remodeling in response to Ang II.
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Affiliation(s)
- Yumei Zhan
- Division of Cardiology, Beth Israel Deaconess Medical Center, Harvard Institutes of Medicine, Boston, Massachusetts 02115, USA
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Sohn EJ, Kang DG, Choi DH, Lee AS, Mun YJ, Woo WH, Kim JS, Lee HS. Effect of methanol extract of Sorbus cortex in a rat model of L-NAME-induced atherosclerosis. Biol Pharm Bull 2005; 28:1239-43. [PMID: 15997106 DOI: 10.1248/bpb.28.1239] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Chronic inhibition of nitric oxide (NO) synthesis by administration of high dose of N(G)-nitro-L-arginine methylester (L-NAME) induces vascular inflammation and subsequent atherosclerosis. We aimed to investigate whether the methanol extract of Sorbus commixta cortex (MSC) is able to prevent inflammatory process in a rat model of L-NAME-induced atherosclerosis. Chronic treatment with low or high doses of MSC prevented the L-NAME-induced increase in monocyte chemoattractant protein-1 (MCP-1) and nuclear factor-kappaB (NF-kappaB) p65 expressions as well as adhesion molecules including intercellular adhesion molecule-1 (ICAM-1) and vascular cell adhesion molecule-1 (VCAM-1), and E-selectin in aorta. In addition, increased endothelin-1 (ET-1) and angiotensin converting enzyme (ACE) expressions and decreased endothelial cell NO synthase (ecNOS) expression in aorta from L-NAME treated group was reversed by treatment with MSC. From the histological examination, aortic segment from the L-NAME-treated rats revealed a thickening of intima and media, which was ameliorated by treatment with MSC. In conclusion, our results indicate that MSC can prevent atherosclerosis by inhibiting vascular over-expressions of vasoactive materials, pro-inflammatory transcription factor, and adhesion molecules and by augmenting ecNOS in chronic L-NAME-treated rat model.
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Affiliation(s)
- Eun Jin Sohn
- Professional Graduate School of Oriental Medicine and Medicinal Resources Research Institute (MeRRI), Wonkwang University, Jeonbuk, Republic of Korea
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Nabah YNA, Mateo T, Cerdá-Nicolás M, Alvarez A, Martinez M, Issekutz AC, Sanz MJ. L-NAME induces direct arteriolar leukocyte adhesion, which is mainly mediated by angiotensin-II. Microcirculation 2005; 12:443-53. [PMID: 16020392 DOI: 10.1080/10739680590960962] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
OBJECTIVE Acute inhibition (1 h) of nitric oxide synthase (NOS) with L-NAME causes leukocyte recruitment in the rat mesenteric postcapillary venules that is angiotensin-II (Ang-II) dependent. Since 4-h exposure to Ang-II provokes arteriolar leukocyte adhesion, this study was designed to investigate whether subacute (4-h) NOS inhibition also causes this effect. METHODS Rats were intraperitoneally injected with saline, L-NAME, or 1H-[1,2,4]-oxidazolol-[4,3-a]-quinoxalin-1-one (ODQ). Leukocyte accumulation in the mesenteric microcirculation was examined 4 h later via intravital microscopy. Some groups were pretreated with losartan, an AT(1) Ang-II receptor antagonist. RESULTS At 4-h, L-NAME caused a significant increase in arteriolar leukocyte adhesion and leukocyte-endothelial cell interactions in postcapillary venules. Mononuclear cells were the predominant leukocytes attached to the arteriolar endothelium. Administration of losartan inhibited L-NAME-induced arteriolar leukocyte adhesion by 90%. L-NAME provoked increased expression of P-selectin, E-selectin, ICAM-1, and VCAM-1 in arterial endothelium, which was attenuated by losartan pretreatment. Inhibition of guanylyl cyclase with ODQ mimicked the effects exerted by L-NAME and losartan also reduced these effects. CONCLUSIONS NOS inhibition for 4-h results in the attachment of leukocytes to the arterial endothelium, a critical event in disease states such as hypertension and atherosclerosis, which could be prevented by the administration of AT(1)Ang-II receptor antagonists.
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Benter IF, Francis I, Cojocel C, Juggi JS, Yousif MHM, Canatan H. Contribution of cytochrome P450 metabolites of arachidonic acid to hypertension and end-organ damage in spontaneously hypertensive rats treated with l-NAME. ACTA ACUST UNITED AC 2005; 25:143-54. [PMID: 16176445 DOI: 10.1111/j.1474-8673.2005.00343.x] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
1 The purpose of this study was to examine the effect of inhibition of the formation of cytochrome P450 metabolites of arachidonic acid with 1-aminobenzotriazole (ABT) on the development of hypertension and end-organ damage in spontaneously hypertensive rats (SHR) chronically treated with nitric oxide synthesis inhibitor L-NAME (SHR-L-NAME). 2 Administration of L-NAME in drinking water (80 mg l(-1)) to SHR for 3 weeks significantly elevated mean arterial blood pressure (MABP) (223 +/- 4 mmHg) as compared to SHR controls drinking regular water (165 +/- 3 mmHg). The administration of ABT (50 mg kg(-1) i.p. alt diem) for 6 days significantly attenuated elevation of blood pressure in SHR-L-NAME (204 +/- 4 mmHg). 3 L-NAME-induced increase in urine volume and protein was significantly lower in ABT-treated animals. 4 The impaired vascular responsiveness to noradrenaline and isoprenaline in the perfused mesenteric vascular bed of SHR-L-NAME-treated animals was significantly improved by ABT treatment. 5 Morphological studies of the kidneys and hearts showed that treatment with ABT minimized the extensive arterial fibrinoid necrosis, arterial thrombosis, significant narrowing of arterial lumen with marked arterial hyperplastic arterial changes that were observed in vehicle treated SHR-L-NAME. 6 In isolated perfused hearts, recovery of left ventricular function from 40 min of global ischaemia was significantly better in ABT-treated SHR-L-NAME. 7 These results suggest that in hypertensive individuals with endothelial dysfunction and chronic NO deficiency, inhibitors of 20-HETE synthesis may be able to attenuate development of high blood pressure and end-organ damage.
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Affiliation(s)
- I F Benter
- Department of Pharmacology and Toxicology, Faculty of Medicine, Kuwait Univesity, P.O. box 24923, Safat 13110, Kuwait
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Abstract
Adiponectin is an adipocyte-derived anti-atherogenic protein. Adiponectin levels are decreased in patients and animal models with obesity, diabetes, and coronary artery disease. However, the mechanism by which adiponectin levels are reduced remains unknown. Since hypoadiponectinemia is closely linked to endothelial dysfunction, we examined the regulation of adiponectin in a rat model of chronic blockade of nitric oxide (NO) synthesis by N omega-nitro-L-arginine methyl ester (L-NAME). Decreased production of NO and increased production of O2- were observed in aorta from L-NAME-treated rats. Plasma adiponectin levels and adiponectin mRNA levels of adipose tissue were markedly decreased in L-NAME-treated rats. Cotreatment of pioglitazone (PIO) or allopurinol (ALL) with L-NAME restored plasma adiponectin concentration and fat adiponectin mRNA levels to control levels. Thus, adiponectin levels were decreased in L-NAME-treated rats, however, they returned to normal following administration of PIO due to transcriptional activation of the adiponectin gene, as well as administration of ALL, likely due to elimination of oxidative stress. Oxidative stress appears to be an important cause of hypoadiponectinemia.
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Affiliation(s)
- Sachiko Hattori
- Department of Endocrinology and Metabolism, Dokkyo University School of Medicine, Mibu, Tochigi, Japan
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66
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Oliveira MVB, Badia E, Carbonneau MA, Grimaldi P, Fouret G, Lauret C, Léger CL. Potential anti-atherogenic cell action of the naturally occurring 4-O-methyl derivative of gallic acid on Ang II-treated macrophages. FEBS Lett 2005; 577:239-44. [PMID: 15527792 DOI: 10.1016/j.febslet.2004.10.015] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2004] [Revised: 10/05/2004] [Accepted: 10/05/2004] [Indexed: 10/26/2022]
Abstract
We have recently established that the blood concentrations of gallic acid (GA), a polyphenolic component naturally found in food, and its O-methyl derivatives are very low (practically < or = 1 microM) in physiological (postprandial) condition. Using acellular oxidant systems and macrophage-differentiated promonocytes (MDPs) THP-1, we show here that the direct and indirect (through depressing effect on the superoxide cell production) antioxidant properties of these components were not effective at these concentrations. In contrast, 4-O-methyl GA was the most efficient component to depress AT1R and CD36 mRNA expression in Ang II-treated MDPs, suggesting a strong inhibition of Ang II-triggered pro-atherogenic mechanisms of foam cell formation.
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Affiliation(s)
- Maria V Bizerra Oliveira
- Laboratoire de Nutrition Humaine et Athérogénèse, EA 2993, Institut de Biologie, Université Montpellier I, Montpellier, France
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67
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Toba H, Nakagawa Y, Miki S, Shimizu T, Yoshimura A, Inoue R, Asayama J, Kobara M, Nakata T. Calcium Channel Blockades Exhibit Anti-Inflammatory and Antioxidative Effects by Augmentation of Endothelial Nitric Oxide Synthase and the Inhibition of Angiotensin Converting Enzyme in the NG-Nitro-L-Arginine Methyl Ester-Induced Hypertensive Rat Aorta: Vasoprotective Effects beyond the Blood Pressure-Lowering Effects of Amlodipine and Manidipine. Hypertens Res 2005; 28:689-700. [PMID: 16392774 DOI: 10.1291/hypres.28.689] [Citation(s) in RCA: 50] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Long-acting dihydropyridine calcium channel blockades have been shown to limit the progression of atherosclerosis and decrease the incidence of cardiovascular events in humans and animals. To investigate the vasoprotective effects beyond the blood pressure-lowering effects of these agents, amlodipine (20 mg/kg/ day) and manidipine (10 mg/kg/day) were administered by gavage to N(G)-nitro-L-arginine methyl ester (L-NAME)-induced hypertensive rats for 2 weeks. L-NAME treatment (0.7 mg/ml in drinking water) significantly decreased the gene and protein expression of endothelial nitric oxide synthase (eNOS) and increased nicotinamide adenine dinucleotide phosphate (NADPH) oxidase, vascular cell adhesion molecule-1 (VCAM-1), and monocyte chemoattractant protein-1 (MCP-1) mRNA levels in the aorta, as determined by Western blotting and reverse transcription (RT)-polymerase chain reaction (PCR). Amlodipine and manidipine normalized the decreased expression of eNOS gene and protein, and attenuated the overexpression of NADPH oxidase, VCAM-1, and MCP-1 mRNA. Furthermore, amlodipine and manidipine prevented the L-NAME-induced increase in the angiotensin converting enzyme (ACE) mRNA content, thereby restoring control levels in the aorta. On the other hand, hydralazine treatment had no such effect in L-NAME treated rats. Furthermore, the increased expression of manganese superoxide dismutase (Mn-SOD) by L-NAME treatment was not affected by amlodipine, manidipine, or hydralazine. We concluded that the direct anti-inflammatory and antioxidative effects of calcium channel blockades in the aorta of rats with L-NAME-induced hypertension were not likely to have been mediated by the blood pressure-lowering action of these agents, but instead these beneficial effects appear to have been mediated by an augmentation of eNOS expression and by the inhibition of the expression of ACE.
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Affiliation(s)
- Hiroe Toba
- Department of Clinical Pharmacology, Kyoto Pharmaceutical University, Kyoto, Japan.
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68
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Rauchová H, Pechánová O, Kunes J, Vokurková M, Dobesová Z, Zicha J. Chronic N-Acetylcysteine Administration Prevents Development of Hypertension in N.OMEGA.-Nitro-L-Arginine Methyl Ester-Treated Rats: The Role of Reactive Oxygen Species. Hypertens Res 2005; 28:475-82. [PMID: 16156512 DOI: 10.1291/hypres.28.475] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
The aim of this study was to evaluate the production of superoxide anions as well as their role in the induction and/or maintenance of high blood pressure in rats with N(omega)-nitro-L-arginine methyl ester (L-NAME)-induced hypertension. In the preventive study, we compared adult Wistar rats treated with L-NAME for 4 weeks with L-NAME-treated rats that were simultaneously given N-acetylcysteine (NAC) in their drinking water. Basal blood pressure, superoxide production, conjugated dienes concentration and NO synthase (NOS) activity were measured at the end of the experiment. Chronic NOS inhibition by L-NAME treatment increased blood pressure, enhanced superoxide production in the aorta and elevated the concentration of conjugated dienes in the heart and kidney. All these changes were prevented by simultaneous NAC administration, which augmented NOS activity in L-NAME-treated rats. In the therapeutic study, the effects of chronic NAC treatment were studied in rats with established hypertension which developed during 4 weeks of L-NAME administration. The blood pressure effects of chronic NAC treatment in established L-NAME hypertension were only moderate, although this treatment also restored NOS activity and lowered conjugated dienes in the heart and kidney. Since chronic NAC treatment had better preventive than therapeutic effects, it seems that reactive oxygen species play a more important role in the induction than in the maintenance of L-NAME hypertension.
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Affiliation(s)
- Hana Rauchová
- Institute of Physiology, Academy of Sciences of the Czech Republic, Prague, Czech Republic
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69
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Husain K. Physical conditioning modulates rat cardiac vascular endothelial growth factor gene expression in nitric oxide-deficient hypertension. Biochem Biophys Res Commun 2004; 320:1169-74. [PMID: 15249212 DOI: 10.1016/j.bbrc.2004.06.058] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2004] [Indexed: 12/15/2022]
Abstract
Many individuals with cardiac diseases undergo periodic physical conditioning with or without medication to improve cardiovascular health. Therefore, this study investigated the interaction of physical training and chronic nitric oxide synthase (NOS) inhibitor (nitro-L-arginine methyl ester, L-NAME) treatment on blood pressure (BP), cardiac vascular endothelial factor (VEGF) gene expression, and nitric oxide (NO) systems in rats. Fisher 344 rats were divided into four groups and treated as follows: (1) sedentary control, (2) exercise training (ET) for 8 weeks, (3) L-NAME (10mg/kg, s.c. for 8 weeks), and (4) ET+L-NAME. BP was monitored with tail-cuff method. The animals were sacrificed 24h after last treatments and hearts were isolated and analyzed. Physical conditioning significantly increased respiratory exchange ratio, cardiac NO levels, NOS activity, endothelial eNOS, and inducible iNOS protein expression as well as VEGF gene expression. Training also caused depletion of cardiac malondialdehyde (MDA) levels indicating the beneficial effects of the training. Chronic L-NAME administration resulted in a depletion of cardiac NO level, NOS activity, and eNOS, nNOS, and iNOS protein expressions, as well as VEGF gene expression (2-fold increase in VEGF mRNA). Chronic L-NAME administration also enhanced cardiac MDA levels indicating cardiac oxidative injury. These biochemical changes were accompanied by increases in BP after L-NAME administration. Interaction of training and NOS inhibitor treatment resulted in normalization of BP and up-regulation of cardiac VEGF gene expression. The data suggest that physical conditioning attenuated the oxidative injury caused by chronic NOS inhibition by up-regulating the cardiac VEGF and NO levels and lowering the BP in rats.
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Affiliation(s)
- Kazim Husain
- Department of Pharmacology and Toxicology, Ponce School of Medicine, P.O. Box 7004, Ponce, PR 00732-7004, USA.
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70
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Linardi A, Panunto PC, Ferro ES, Hyslop S. Peptidase activities in rats treated chronically with N-nitro-l-arginine methyl ester (L-NAME). Biochem Pharmacol 2004; 68:205-14. [PMID: 15193992 DOI: 10.1016/j.bcp.2004.03.016] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2003] [Accepted: 03/17/2004] [Indexed: 10/26/2022]
Abstract
The chronic treatment of rats with N(omega)-nitro-L-arginine methyl ester (L-NAME), an inhibitor of nitric oxide (NO) biosynthesis, results in hypertension. This inhibition of NO production results in activation of the renin-angiotensin system, with increased activity of the carboxypeptidase angiotensin I-converting enzyme (ACE). Since chronic NO inhibition increases ACE activity, we hypothesized that this inhibition could also affect the activities of other peptidases involved in cardiovascular functions. To test this possibility, we examined the activities of aminopeptidase M (APM), dipeptidyl peptidase IV (DPP IV), metalloendopeptidase 24.15 (MEP 24.15) and neutral endopeptidase 24.11 (NEP 24.11) in rat brain, heart, kidney, liver, lung and thoracic aorta. Male Wistar rats were treated chronically with L-NAME (80mgkg(-1) per day) administered in the drinking water for 4 weeks and their organs then removed and processed for the determination of peptidase activities. Treatment with L-NAME did not significantly alter the activities of the four peptidases in brain, heart, kidney, liver and lung. In contrast, in aorta, the activity of APM was slightly but significantly reduced whereas those of DPP IV and MEP 24.15 were markedly enhanced; NEP 24.11 was not detected in this tissue. Immunoblotting for DPP IV and MEP 24.15 showed increased expression in aortic tissue. Neither L-NAME (1-100microM) nor the NO donors sodium nitroprusside and 3-morpholinosydnonimine (SIN-1; 1-100microM) had any consistent effect on the activity of recombinant MEP 24.15 or renal DPP IV. The importance of MEP 24.15 in peptide metabolism was confirmed in pentobartibal-anesthetized rats pretreated with the MEP 24.15 inhibitor N-[1-(R,S)-carboxy-3-phenylpropyl]-Ala-Aib-Tyr-p-aminobenzoate (JA2), which significantly potentiated the hypotensive response to bradykinin. The altered peptidase activities seen in aorta may contribute to modulating vascular responses in this model of hypertension.
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Affiliation(s)
- Alessandra Linardi
- Departamento de Farmacologia, Faculdade de Ciências Médicas, Universidade Estadual de Campinas, Campinas, SP, Brazil
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71
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72
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Kitamoto S, Egashira K. Anti-monocyte chemoattractant protein-1 gene therapy for cardiovascular diseases. Expert Rev Cardiovasc Ther 2004; 1:393-400. [PMID: 15030267 DOI: 10.1586/14779072.1.3.393] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Recent studies have revealed that increased expression of monocyte chemoattractant protein (MCP)-1 plays a central role in the pathogenesis of cardiovascular diseases. 7ND is the amino-terminal deletion mutant of human MCP-1 and works as a dominant negative inhibitor of MCP-1. We devised a new strategy of anti-MCP-1 gene therapy by transfecting the 7ND gene into skeletal muscles. 7ND gene transfection suppressed arteriosclerotic changes induced by chronic inhibition of nitric oxide synthesis in rats and inhibited the development, progression and destabilization of atherosclerosis in apolipoprotein E knockout mice. This strategy also reduced restenosis after balloon injury in rats, rabbits and monkeys, and reduced neointimal formation after stent implantation in rabbits and monkeys. This new strategy can be a useful and feasible gene therapy against MCP-1 related cardiovascular diseases.
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Affiliation(s)
- Shiro Kitamoto
- Department of Cardiovascular Medicine, Graduate School of Medical Sciences, Kyushu University, 3-1-1, Maidashi, Higashi-ku, Fukuoka 812-8582, Japan
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Ohtani K, Egashira K, Usui M, Ishibashi M, Hiasa KI, Zhao Q, Aoki M, Kaneda Y, Morishita R, Takeshita A. Inhibition of neointimal hyperplasia after balloon injury by cis-element 'decoy' of early growth response gene-1 in hypercholesterolemic rabbits. Gene Ther 2004; 11:126-32. [PMID: 14712296 DOI: 10.1038/sj.gt.3302153] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Early growth response factor-1 (Egr-1) is a transcription factor that is rapidly activated after vascular injury and thus might contribute to vascular proliferation and inflammation. We hypothesized that Egr-1 might therefore be a therapeutic target against restenosis. Hypercholesterolemic rabbits were intraluminally administered synthetic DNA as a 'decoy' against Egr-1 immediately after carotid artery balloon injury. Efficient transfection was confirmed by the delivery of a fluorescence-labeled decoy. Gel mobility-shift assay showed increased Egr-1 activity after balloon injury and its prevention by Egr-1 decoy transfection in vivo. Egr-1 decoy transfection attenuated early inflammation and proliferation and later neointimal hyperplasia. In addition, Egr-1 decoy transfection reduced gene expression and protein production of Egr-1-dependent genes such as platelet-derived growth factor-B, transforming growth factor-beta1, and monocyte chemoattractant protein-1. The Egr-1 pathway has an essential role in the pathogenesis of neointimal hyperplasia after balloon injury in hypercholesterolemic rabbits. This decoy strategy is a potential practical form of therapy for human restenosis.
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Affiliation(s)
- K Ohtani
- Department of Cardiovascular Medicine, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan
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74
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Wu L, Iwai M, Li Z, Shiuchi T, Min LJ, Cui TX, Li JM, Okumura M, Nahmias C, Horiuchi M. Regulation of Inhibitory Protein-κB and Monocyte Chemoattractant Protein-1 by Angiotensin II Type 2 Receptor-Activated Src Homology Protein Tyrosine Phosphatase-1 in Fetal Vascular Smooth Muscle Cells. Mol Endocrinol 2004; 18:666-78. [PMID: 14684844 DOI: 10.1210/me.2003-0053] [Citation(s) in RCA: 56] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
In the present study we examined the effects of angiotensin II (Ang II) type 2 (AT(2)) receptor stimulation on AT(1) receptor-mediated monocyte chemoattractant protein-1 (MCP-1) expression and the possible mechanisms of AT(2) receptor-mediated signaling in cultured rat fetal vascular smooth muscle cells, which express both AT(1) and AT(2) receptors. Ang II stimulation induced MCP-1 mRNA expression as well as an increase in nuclear factor-kappaB (NF-kappaB) binding to the corresponding cis DNA element of the MCP-1 promoter region and a decrease in the cytosolic inhibitory protein-kappaB (IkappaB) protein level via AT(1) receptor stimulation, whereas stimulation of the AT(2) receptor decreased Ang II-induced MCP-1 expression, NF-kappaB DNA binding, and IkappaB degradation, suggesting that activation of the AT(2) receptor attenuated AT(1) receptor-mediated MCP-1 expression via a decrease in NF-kappaB DNA binding and an increase in IkappaB stability. Moreover, we demonstrated that AT(2) receptor stimulation attenuated TNFalpha-mediated NF-kappaB activation and MCP-1 expression. A tyrosine phosphatase inhibitor, orthovanadate, attenuated the AT(2) receptor-mediated increase in IkappaB protein. Moreover, we observed that two IkappaB subunits (IkappaBalpha and IkappaBbeta) were tyrosine-phosphorylated after Ang II stimulation. Transfection of a dominant-negative Src homology protein tyrosine phosphatase-1 mutant into vascular smooth muscle cells inhibited the AT(2) receptor-mediated increase in IkappaB, leading to a significant increase in AT(1) receptor-induced NF-kappaB activation and MCP-1 expression. Taken together, our results demonstrated that AT(2) receptor stimulation attenuated MCP-1 expression via IkappaB stabilization, and Src homology protein tyrosine phosphatase-1 might play a critical role in the transcriptional regulation of MCP-1 expression through the control of IkappaB protein stability.
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MESH Headings
- Angiotensin II/antagonists & inhibitors
- Angiotensin II/pharmacology
- Angiotensin II Type 1 Receptor Blockers
- Angiotensin II Type 2 Receptor Blockers
- Animals
- Cells, Cultured
- Chemokine CCL2/genetics
- Chemokine CCL2/metabolism
- Cytosol/drug effects
- Cytosol/metabolism
- Gene Expression Regulation
- I-kappa B Proteins/drug effects
- I-kappa B Proteins/genetics
- I-kappa B Proteins/metabolism
- Imidazoles/pharmacology
- Intracellular Signaling Peptides and Proteins
- Muscle, Smooth, Vascular/cytology
- Muscle, Smooth, Vascular/embryology
- Muscle, Smooth, Vascular/metabolism
- Mutation
- NF-kappa B
- Oligopeptides/pharmacology
- Protein Phosphatase 1
- Protein Tyrosine Phosphatase, Non-Receptor Type 1
- Protein Tyrosine Phosphatase, Non-Receptor Type 6
- Protein Tyrosine Phosphatases/drug effects
- Protein Tyrosine Phosphatases/genetics
- Protein Tyrosine Phosphatases/metabolism
- Pyridines/pharmacology
- Rats
- Rats, Sprague-Dawley
- Receptor, Angiotensin, Type 1/drug effects
- Receptor, Angiotensin, Type 1/metabolism
- Receptor, Angiotensin, Type 2/drug effects
- Receptor, Angiotensin, Type 2/metabolism
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Affiliation(s)
- Lan Wu
- Department of Medical Biochemistry, Ehime University School of Medicine, Shigenobu, Onsen-gun, Ehime 791-0295, Japan
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75
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Behr TM, Willette RN, Coatney RW, Berova M, Angermann CE, Anderson K, Sackner-Bernstein JD, Barone FC. Eprosartan improves cardiac performance, reduces cardiac hypertrophy and mortality and downregulates myocardial monocyte chemoattractant protein-1 and inflammation in hypertensive heart disease. J Hypertens 2004; 22:583-92. [PMID: 15076165 DOI: 10.1097/00004872-200403000-00022] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
OBJECTIVE The purpose of this investigation was to determine whether angiotensin II receptor (AII1R) antagonism interferes with cardiac monocyte chemoattractant protein-1 (MCP-1) expression in hypertrophic cardiomyopathy and failure. DESIGN We studied the effects of the AII1R antagonist eprosartan on MCP-1 expression, and on the recruitment of macrophages into the myocardium in a model of cardiac hypertrophy and morbidity/mortality. METHODS Stroke-prone spontaneously hypertensive rats fed a high-salt, high-fat diet (SFD) developed heart failure characterized by left ventricular (LV) hypertrophy/pathology and hypocontractility. These rats received either normal diet, SFD, or SFD with the daily administration of 30 mg/kg eprosartan for 28 weeks. LV function and wall thickness was assessed by echocardiography, MCP-1 expression was measured by TaqMan real-time polymerase chain reaction, enzyme-linked immunosorbent assay and immunohistochemistry, and macrophage infiltration into the LV was determined by microscopy. RESULTS Eprosartan reduced the rate of morbidity/mortality (P = 0.001), LV MCP-1 mRNA (P < 0.05) and protein expression (P < 0.01), and LV macrophage infiltration (P < 0.01), while preserving ventricular function (P < 0.05). Eprosartan also produced a moderate (16%; P < 0.05) decrease in blood pressure. CONCLUSIONS These data demonstrate that AII1R antagonism in an animal model of hypertensive heart disease reduces MCP-1 expression in the myocardium that results in reduced macrophage recruitment. These effects parallel the preservation of LV systolic function and the reduction in cardiac remodeling/disease progression and reduced morbidity/mortality. Suppression of MCP-1 expression might explain in part the beneficial effects of AII1R antagonism in this model.
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Affiliation(s)
- Thomas M Behr
- Medizinische Poliklinik, Department of Cardiology, University of Wuerzburg, Germany.
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76
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Shimizu H, Miyoshi M, Matsumoto K, Goto O, Imoto T, Watanabe T. The Effect of Central Injection of Angiotensin-Converting Enzyme Inhibitor and the Angiotensin Type 1 Receptor Antagonist on the Induction by Lipopolysaccharide of Fever and Brain Interleukin-1β Response in Rats. J Pharmacol Exp Ther 2003; 308:865-73. [PMID: 14617687 DOI: 10.1124/jpet.103.060392] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
We recently reported an involvement of peripheral angiotensin II (ANG II) in the development of both the fever and the peripheral interleukin (IL)-1beta production induced in rats by a systemic injection of lipopolysaccharide (LPS). The present study was performed to investigate whether brain ANG II contributes to the fever and IL-1beta production in the rat brain induced by i.c.v. injection of LPS. LPS (0.2 and 2 microg i.c.v.) induced dose-related fevers and increases in the brain (hypothalamus, hippocampus, and cerebellum) concentrations of IL-1beta. These effects were significantly inhibited by i.c.v. administration of either an angiotensin-converting-enzyme (ACE) inhibitor or an angiotensin type 1 (AT(1)) receptor antagonist. By contrast, the ACE inhibitor had no effect on the IL-1beta (i.c.v.)-induced fever, whereas the AT(1) receptor antagonist enhanced (rather than reduced) it. The AT(1) receptor antagonist had no effect on the brain levels of prostaglandin E(2) in rats given an i.c.v. injection of IL-1beta. These results suggest that in rats, brain ANG II and AT(1) receptors are involved in the LPS-induced production of brain IL-1beta, thus contributing to the fever induced by the presence of LPS within the brain.
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Affiliation(s)
- Hideki Shimizu
- Department of Functional, Morphological, and Regulatory Science, Tottori University Faculty of Medicine, Yonago, Tottori, Japan
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77
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Kataoka C, Egashira K, Ishibashi M, Inoue S, Ni W, Hiasa KI, Kitamoto S, Usui M, Takeshita A. Novel anti-inflammatory actions of amlodipine in a rat model of arteriosclerosis induced by long-term inhibition of nitric oxide synthesis. Am J Physiol Heart Circ Physiol 2003; 286:H768-74. [PMID: 14592942 DOI: 10.1152/ajpheart.00937.2002] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
Amlodipine (a new class of calcium channel antagonist) has been shown to limit the progression of arteriosclerosis and decrease the incidence of cardiovascular events. The mechanisms underlying the beneficial effects of amlodipine, however, remain unclear. Therefore, we hypothesized that amlodipine attenuates the development of arteriosclerosis through the inhibition of inflammation in vivo. Long-term inhibition of nitric oxide (NO) by administration of a NO synthase inhibitor, N(omega)-nitro-L-arginine methyl ester (L-NAME), to rats induces coronary vascular inflammation [monocyte infiltration, monocyte chemoattractant protein-1 (MCP-1) expression, increased activity of angiotensin-converting enzyme (ACE)], and arteriosclerosis. Here, we used the rat model to investigate the anti-inflammatory effects of amlodipine in vivo. Treatment with amlodipine markedly inhibited the L-NAME-induced increase in vascular inflammation, oxidative stress, and local ACE and Rho activity and prevented arteriosclerosis. Interestingly, amlodipine prevented the L-NAME-induced increase in MCP-1 receptor CCR2 expression in circulating monocytes. Amlodipine markedly attenuated the high mortality rate at 8 wk of treatment. These data suggest that amlodipine attenuated arteriosclerosis through inhibiting inflammatory disorders in the rat model of long-term inhibition of NO synthesis. The anti-inflammatory effects of amlodipine seem to be mediated not only by the inhibition of local factors such as MCP-1 but also by the decrease in CCR2 in circulating monocytes. Inhibition of the MCP-1 to CCR2 pathway may represent novel anti-inflammatory actions of amlodipine beyond blood pressure lowering.
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Affiliation(s)
- Chu Kataoka
- Department of Cardiovascular Medicine, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan
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78
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Kitamoto S, Egashira K. Gene therapy targeting monocyte chemoattractant protein-1 for vascular disease. J Atheroscler Thromb 2003; 9:261-5. [PMID: 12560586 DOI: 10.5551/jat.9.261] [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: 11/11/2022] Open
Abstract
Monocyte chemoattractant protein-1 (MCP-1) has been shown to play an essential role in the pathogenesis of arteriosclerosis and other vascular diseases, such as restenosis after arterial injury, by recruiting monocytes into the arterial wall. We devised a new strategy for anti-MCP-1 gene therapy against arteriosclerosis by transfecting an amino-terminal deletion mutant (7ND), which lacks the amino-terminal amino acids 2 to 8 of the human MCP-1 gene, into a remote organ (skeletal muscles). Intramuscular transduction with the mutant MCP-1 gene suppressed inflammatory and proliferative changes and arteriosclerosis formation induced by the chronic inhibition of nitric oxide synthesis in rats. 7ND gene transfection also inhibited the initiation, progression, and destabilization of atherosclerosis in Apolipoprotein E-knockout mice. Moreover, the strategy reduced restenosis after balloon injury in rabbits, rats, and monkeys, or neointimal formation after stent implantation in monkeys. This new strategy may be a useful and feasible gene therapy against atherosclerosis and restenosis after angioplasty.
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Affiliation(s)
- Shiro Kitamoto
- Department of Cardiovascular Medicine, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan
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79
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Matz RL, Andriantsitohaina R. Age-related endothelial dysfunction : potential implications for pharmacotherapy. Drugs Aging 2003; 20:527-50. [PMID: 12749750 DOI: 10.2165/00002512-200320070-00005] [Citation(s) in RCA: 66] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Aging per se is associated with abnormalities of the vascular wall linked to both structural and functional changes that can take place at the level of the extracellular matrix, the vascular smooth muscle and the endothelium of blood vessels. Endothelial dysfunction is generally defined as a decrease in the capacity of the endothelium to dilate blood vessels in response to physical and chemical stimuli. It is one of the characteristic changes that occur with age, independently of other known cardiovascular risk factors. This may account in part for the increased incidence of cardiovascular events in elderly people that can be reversed by restoring endothelial function. A better understanding of the mechanisms involved and the aetiopathogenesis of this process will help in the search for new therapeutic agents.Age-dependent alteration of endothelium-dependent relaxation seems to be a widespread phenomenon both in conductance and resistance arteries from several species. In the course of aging, there is an alteration in the equilibrium between relaxing and contracting factors released by the endothelium. Hence, there is a progressive reduction in the participation of nitric oxide and endothelium-derived hyperpolarising factor associated with increased participation of oxygen-derived free radicals and cyclo-oxygenase-derived prostanoids. Also, the endothelin-1 and angiotensin II pathways may play a role in age-related endothelial dysfunction. The use of drugs acting at different levels of these signalling cascades, including antioxidant therapy, lipid-lowering drugs and estrogens, seems to be promising.
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Affiliation(s)
- Rachel L Matz
- Biochemisches Institut, Fachbereich Humanmedizin, Justus Liebig Universität, Giessen, Germany
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80
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Dohi Y, Ohashi M, Sugiyama M, Takase H, Sato K, Ueda R. Candesartan reduces oxidative stress and inflammation in patients with essential hypertension. Hypertens Res 2003; 26:691-7. [PMID: 14620923 DOI: 10.1291/hypres.26.691] [Citation(s) in RCA: 84] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
The present study was designed to test the hypothesis that blockade of angiotensin II type-1 receptors reduces oxidative stress and inflammation in patients with essential hypertension. The study population comprised 132 hypertensive patients, some receiving and others not receiving medical treatment. At enrollment their systolic and/or diastolic blood pressures were > or = 140 and/or > or = 90 mmHg, respectively. The serum concentration of C-reactive protein, and the urine concentrations of 8-epi-prostaglandin F2alpha and 8-hydroxydeoxyguanosine were measured at baseline and after 12 weeks of treatment either with an angiotensin II type-1 receptor blocker, candesartan (8 mg daily) (age 64 +/- 12 years; male/female 28/39; n = 67), or other antihypertensive agents that do not block the renin-angiotensin system (age 65 +/- 10 years, male/female 25/40, n = 65). Candesartan reduced the levels of C-reactive protein (from 0.07 +/- 0.04 [median value +/- median absolute deviation] to 0.06 +/- 0.03 mg/dl, p < 0.0001), 8-epi-prostaglandin F2alpha (from 210 +/- 92 to 148 +/- 59 pg/mg creatinine, p < 0.0001), and 8-hydroxydeoxyguanosine (from 5.7 +/- 1.9 to 4.0 +/- 1.3 ng/mg creatinine, p < 0.0001), while the levels of these markers were not altered after the treatment with other antihypertensive agents. Blood pressure decreased by a similar amount in both groups, and the reductions in the levels of the markers did not correlate with that of blood pressure. These results suggest that candesartan reduces oxidative stress and inflammation in hypertensive patients independently of its effects on blood pressure. This may provide useful information for determining therapeutic strategies to minimize tissue injury by inflammation and oxidative stress in hypertensive patients.
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Affiliation(s)
- Yasuaki Dohi
- Division of Hypertension and Vascular Research, Internal Medicine and Molecular Science, Graduate School of Medical Sciences, Nagoya City University, Mizuho-ku, Nagoya 467-8601, Japan.
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81
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Stanke-Labesque F, Hardy G, Caron F, Cracowski JL, Bessard G. Inhibition of leukotriene synthesis with MK-886 prevents a rise in blood pressure and reduces noradrenaline-evoked contraction in L-NAME-treated rats. Br J Pharmacol 2003; 140:186-94. [PMID: 12967948 PMCID: PMC1574003 DOI: 10.1038/sj.bjp.0705405] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022] Open
Abstract
(1) Long-term treatment of rats with Nomega-nitro-l-arginine methyl ester (l-NAME) induces hypertension associated with inflammatory and vascular changes. Leukotrienes are proinflammatory vasoactive products that are suspected to be involved in the pathogenesis of hypertension. We investigated, in rats chronically treated with l-NAME, the involvement of leukotrienes in the in vivo regulation of blood pressure and the in vitro contraction elicited by noradrenaline in isolated aorta. (2) Rats were randomly assigned to four groups and orally treated for 3 weeks with l-NAME (1 mg ml-1), l-NAME (1 mg ml-1) plus the leukotriene biosynthesis inhibitor MK-886 (0.1 mg ml-1), MK-886 (0.1 mg ml-1) alone or vehicle (Methocel, 0.1%). All the drugs were added to the drinking fluid. (3) The mean arterial blood pressure (MABP) increased significantly in l-NAME-treated rats (173.3+/-9.4 mmHg (n=25)) vs Methocel-treated rats (110.7+/-4.8 mmHg (n=11), P<0.001). Chronic treatment with MK-886 prevented this rise in MABP. (4) Aortic rings with or without endothelium were suspended in organ baths for recording isometric changes in response to noradrenaline. Pretreatment with either MK-886 (10 microm), the CysLT1 receptor antagonist MK571 (1 microm) or the dual CysLT1/CysLT2 receptor antagonist BAY-u9773 (0.1 microm) reduced (P<0.05) noradrenaline-induced contractions in intact aortic rings from l-NAME-treated rats only. (5) Noradrenaline (0.3 microm) induced a two-fold increase in cysteinyl leukotriene (CysLT) release (measured by enzyme immunoassay) in intact aortic rings from l-NAME-treated rats only. (6) These data suggested (1) a role for the 5-lipoxygenase pathway in the regulation of blood pressure in l-NAME-treated rats and (2) the involvement of endothelial CysLTs in noradrenaline-induced contraction in aorta from l-NAME-treated rats.
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82
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Egami K, Murohara T, Shimada T, Sasaki KI, Shintani S, Sugaya T, Ishii M, Akagi T, Ikeda H, Matsuishi T, Imaizumi T. Role of host angiotensin II type 1 receptor in tumor angiogenesis and growth. J Clin Invest 2003; 112:67-75. [PMID: 12840060 PMCID: PMC162282 DOI: 10.1172/jci16645] [Citation(s) in RCA: 248] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
Although the renin angiotensin system (RAS) is a major regulator of vascular homeostasis, the role of the RAS in tumor angiogenesis is little understood. Here we show that host angiotensin II (ATII) type 1 (AT1) receptor plays an important role in angiogenesis and growth of tumor cells engrafted in mice. Subcutaneous B16-F1 melanoma-induced angiogenesis as assessed by tissue capillary density and microangiography was prominent in WT mice but was reduced in AT1a receptor-deficient (AT1a-/-) mice. Consequently, tumor growth rate was significantly slower, and the mouse survival rate was greater, in AT1a-/- mice than in WT mice. Tumor growth was also reduced in WT mice treated with TCV-116, a selective blocker of AT1 receptor. Because the beta-galactosidase gene was inserted into the AT1a gene locus in AT1a-/- mice, the site of beta-galactosidase expression represents the AT1a receptor expression in these mutant mice. In tumor-implanted AT1a-/- mice, the major site of the beta-galactosidase expression was macrophages in tissues surrounding tumors. Moreover, the number of infiltrated macrophages was significantly lower in AT1a-/- mice than in WT mice, and double-immunofluorescence staining revealed that these macrophages expressed VEGF protein intensively. Therefore, the host ATII-AT1 receptor pathway supports tumor-associated macrophage infiltration, which results in enhanced tissue VEGF protein levels. The host ATII-AT1 receptor pathway thereby plays important roles in tumor-related angiogenesis and growth in vivo.
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MESH Headings
- Animals
- Benzimidazoles/pharmacology
- Biphenyl Compounds/pharmacology
- Cyclohexanes
- Endothelial Growth Factors/analysis
- Intercellular Signaling Peptides and Proteins/analysis
- Lymphokines/analysis
- Melanoma, Experimental/blood supply
- Melanoma, Experimental/pathology
- Mice
- Mice, Inbred C57BL
- Neoplasms, Experimental/blood supply
- Neoplasms, Experimental/pathology
- Neovascularization, Pathologic/etiology
- O-(Chloroacetylcarbamoyl)fumagillol
- Receptor, Angiotensin, Type 1
- Receptors, Angiotensin/analysis
- Receptors, Angiotensin/physiology
- Sesquiterpenes/pharmacology
- Tetrazoles
- Vascular Endothelial Growth Factor A
- Vascular Endothelial Growth Factors
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Affiliation(s)
- Kimiyasu Egami
- Department of Cardiology, Nagoya University Graduate School of Medicine, Kurume, Japan
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83
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Abstract
Because vasolidator peptide adrenomedullin (AM) exhibits complicated action, we developed AM knockout mice in order to elucidate the physiological and pathophysiological role of AM. The AM(-/-) mice were embryonic lethal, so we could not evaluate directly the role of AM in this mutant mice. Thus, we loaded angiotensin II (AngII) and salt in AM(+/-) mice, which were viable and fertile. As a result, AngII and salt loading caused coronary vascular damage and left ventricular hypertrophy in AM(+/-) mice more greatly than AM(+/+) mice. Moreover, cuff placement of femoral artery stimulated intimal thickening more severely. This treatment increased local AM levels in AM(+/+) mice but not in AM(+/-) mice. The accelerated organ damage in AM(+/-) mice was accompanied with enhanced production of oxidative stress. Thus, our data suggest that intrinsic AM play a vascular protective role.
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Affiliation(s)
- Katsuyuki Ando
- Department of Nephrology and Endocrinology, University of Tokyo School of Medicine, 7-3-1 Hongo, Tokyo 113-8655, Bunkyoku, Japan
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84
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Miyoshi M, Nagata K, Imoto T, Goto O, Ishida A, Watanabe T. ANG II is involved in the LPS-induced production of proinflammatory cytokines in dehydrated rats. Am J Physiol Regul Integr Comp Physiol 2003; 284:R1092-7. [PMID: 12626369 DOI: 10.1152/ajpregu.00700.2002] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
We have previously reported results that led us to speculate that ANG II is involved in the LPS-induced production of proinflammatory cytokines, especially under dehydrated conditions. To test this possibility, in this study we examined the effects of an angiotensin-converting enzyme (ACE) inhibitor and an antagonist of the type-1 ANG II receptor (AT(1) receptor) on the LPS-induced production of the proinflammatory cytokines IL-1 and IL-6 in dehydrated rats. A single intravenous injection of LPS induced a marked increase in the expression of IL-1beta mRNA in the liver, an effect that was significantly attenuated by pretreatment with the ACE inhibitor. Furthermore, the ACE inhibitor reduced the LPS-induced increase in the hepatic concentration of IL-1beta protein. When the AT(1)-receptor antagonist was given intravenously before the LPS, the increase in the hepatic concentration of IL-1beta was significantly reduced. Finally, the ACE inhibitor reduced the LPS-induced increase in the plasma concentration of IL-6. These results represent the first in vivo evidence that ANG II and its AT(1) receptor play important roles in the production of proinflammatory cytokines that is induced by LPS under dehydrated conditions.
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Affiliation(s)
- Michio Miyoshi
- The Department of Physiology, Tottori University Faculty of Medicine, Yonago, Tottori 683, Japan
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85
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Abstract
PURPOSE OF REVIEW In this review, we summarize the more recent clinical evidence highlighting the importance of vascular inflammation in terms of clinical risk prediction, and the mechanisms mediating the upregulation of inflammatory mediators in cardiovascular disease and hypertension. RECENT FINDINGS Markers of inflammation have been shown to be upregulated in different forms of cardiovascular disease, and to correlate with vascular risk. Atherosclerosis is characterized by chronic inflammation of the vascular wall. The I-kappaB/nuclear factor-kappaB system is considered a major intracellular inflammatory pathway, mediating most of the vascular inflammatory responses. Increasing evidence indicates that hypertension, through the vasoactive peptides angiotensin and endothelin-1, promotes and accelerates the atherosclerotic process via inflammatory mechanisms. In animal and human studies proinflammatory properties of angiotensin II have been demonstrated in large conduit and small arteries, in the kidney as well as in the heart. The angiotensin II receptors involved in the inflammatory process and the interaction between angiotensin II and nitric oxide in mediating vascular inflammation have been identified. In addition, recent advances concerning the role of endothelin-1 as another important mediator of chronic inflammation in the vascular wall has been documented, and the relationship between endothelin-1 and angiotensin II on vascular inflammation demonstrated. SUMMARY Inflammatory mechanisms are important participants in the pathophysiology of hypertension and cardiovascular disease. The identification of useful markers of inflammation, of new therapeutic targets to interfere with these mechanisms, and the evaluation of the efficacy of antiinflammatory treatments will allow progress in our ability to combat cardiovascular disease and the complications of hypertension.
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Affiliation(s)
- Agostino Virdis
- Multidisciplinary Research Group on Hypertension, Quebec, Canada
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86
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Abstract
Nitric oxide is involved in the regulation of resting vascular tone, adaptation of blood flow to metabolic demand of tissue, and adaptation of vessel diameter to volume of inflow, ie, flow-mediated dilation. Arterial hypertension is associated with an increased vascular tone of resistance vessels, a reduced compliance of conduit arteries, along with a thickening of the intima-media leading to vascular remodeling. Dysfunctional endothelium triggers such maladaptive processes. A reduced bioavailability of nitric oxide has been shown in hypertensive individuals dependent on the duration and severity of arterial hypertension. Angiotensin-converting enzyme inhibitors reverse endothelial dysfunction, whereas a concomitant reduction in significant cardiac events due to improved bioavailability has yet to be established. Long-term follow-up studies in individuals with manifest endothelial dysfunction and in offspring from hypertensive patients underscore the prognostic and genetic significance of a reduced nitric oxide bioavailability for the pathophysiology of arterial hypertension.
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Affiliation(s)
- Malte Kelm
- Medizinische Klinik und Poliklinik B, Klinik für Kardiologie, Pneumologie und Angiologie, Moorenstrasse 5, 40225 Düsseldorf, Germany.
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87
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Usui M, Egashira K, Ohtani K, Kataoka C, Ishibashi M, Hiasa KI, Katoh M, Zhao Q, Kitamoto S, Takeshita A. Anti-monocyte chemoattractant protein-1 gene therapy inhibits restenotic changes (neointimal hyperplasia) after balloon injury in rats and monkeys. FASEB J 2002; 16:1838-40. [PMID: 12223446 DOI: 10.1096/fj.02-0094fje] [Citation(s) in RCA: 73] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Prevention of restenosis after coronary intervention is a major clinical challenge, which highlights the need of new therapeutic options. Vascular injury may involve inflammatory responses that accelerate the recruitment and activation of monocytes through the activation of chemotactic factors, including monocyte chemoattractant protein-1 (MCP-1). However, there is no definitive evidence supporting the role of MCP-1 in restenosis. We recently devised a new strategy for anti-MCP-1 gene therapy by transfecting an N-terminal deletion mutant of the MCP-1 gene into skeletal muscles. We demonstrate here that this strategy suppressed monocyte infiltration/activation in the injured site and markedly inhibited restenotic changes (neointimal hyperplasia) after balloon injury of the carotid artery in rats and monkeys. This strategy also suppressed the local production of MCP-1 and inflammatory cytokines. Therefore, monocyte infiltration and activation mediated by MCP-1 are essential in the development of restenotic changes after balloon injury. This strategy may be a useful form of gene therapy against human restenosis.
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Affiliation(s)
- Makoto Usui
- Department of Cardiovascular Medicine, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan
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88
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Abstract
Nitric oxide degradation linked to endothelial dysfunction plays a central role in cardiovascular diseases. Superoxide producing enzymes such as NADPH oxidase and xanthine oxidase are responsible for NO degradation as they generate a variety of reactive oxygen species (ROS). Moreover, superoxide is rapidly degraded by superoxide dismutase to produce hydrogen peroxide leading to the uncoupling of NO synthase and production of increased amount of superoxide. Angiotensin II is an important stimulus of NADPH oxidase. Through its AT(1) receptor, Ang II stimulates the long-term increase of several membrane component of NADPH oxidase such as P(22) phox or nox-1 and causes an increased activity of NADPH oxidase with inactivation of NO leading to impaired endothelium-dependent vasorelaxation, vascular smooth muscle cell hypertrophy, proliferation and migration, extracellular matrix formation, thrombosis, cellular infiltration and inflammatory reaction. Several preclinical and clinical studies have now confirmed the involvement of the AT(1) receptor in endothelial dysfunction. It is proposed that the AT(2) receptor counterbalances the deleterious effect of the Ang II-induced AT(1) receptor stimulation through bradykinin and NOS stimulation. This mechanism could be especially relevant in pathological cases when the NADPH oxidase activity is blocked with an AT(1) receptor antagonist.
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89
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Abstract
The renin-angiotensin system plays a major role in the pathogenesis of atherosclerosis. Most known effects of angiotensin II are mediated via activation of the AT(1)-receptor, which is in turn influenced to a great degree by levels of expression of the AT(1)-receptor. AT(1)-receptor activation is not only involved in vasoconstriction, water and salt homoeostasis and control of other neurohumoral systems, but also induces reactive oxygen species production, cellular hypertrophy and hyperplasia and apoptosis. Expression of this G-protein-coupled receptor is regulated by multiple factors. Among other conditions, oestrogen deficiency and hypercholesterolaemia increase AT(1)-receptor expression. Experimental data suggest that this augments the actions of angiotensin II, contributes to endothelial dysfunction, increases vascular production of reactive oxygen species, and via these mechanisms promotes atherosclerosis. Because of this, AT(1)-receptor regulation is likely to be critical in the development and progression of vascular lesions. Interventional studies demonstrated that ACE inhibitors which reduce AT(1)-receptor activation, improve endothelial dysfunction and inhibit onset and progression of atherosclerosis. The more specific AT(1)-receptor antagonists have also been shown to decrease blood pressure, protect renal function and to improve endothelial function. Thus, there is compelling evidence that AT(1)-receptor activation participates in the pathogenesis of atherosclerosis, and more importantly, that treatment regimens aiming at inhibition of AT(1)-receptor activation are promising anti-atherosclerotic therapeutic options.
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Affiliation(s)
- G Nickenig
- Medizinische Klinik und Poliklinik Innere Medizin III, Universität des Saarlandes, Homburg/Saar, Germany.
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90
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Abstract
The vascular endothelium is a dynamic endocrine organ that regulates vascular tone, local homeostasis, and the fibro-inflammatory-proliferative process. These responses are mediated by various substances released from the endothelium in response to physiologic stimuli, including prostacyclin, endothelin and, most importantly, nitric oxide (NO). NO mediates vasodilation and inhibits platelet aggregation, thrombus formation, expression of adhesion molecules and chemokines for leukocytes, and oxidative stress. It also attenuates growth and proliferation of vascular smooth muscle cells. Risk factors for atherosclerosis, such as hypercholesterolemia, hypertension, diabetes and cigarette smoking, impair endothelial function, which leads to atherosclerosis and results in ischemic manifestations such as acute coronary syndrome and stroke. Thus, therapeutic intervention aimed at increasing NO bioavailability by statins or angiotensin-converting enzyme inhibitors might improve patient prognosis. Vascular endothelial function is an important and clinically relevant therapeutic target for cardiovascular disease.
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Affiliation(s)
- Kensuke Egashira
- Department of Cardiovascular Medicine, School of Medical Sciences, Kyushu University, Fukuoka, Japan.
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91
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Kubo-Inoue M, Egashira K, Usui M, Takemoto M, Ohtani K, Katoh M, Shimokawa H, Takeshita A. Long-term inhibition of nitric oxide synthesis increases arterial thrombogenecity in rat carotid artery. Am J Physiol Heart Circ Physiol 2002; 282:H1478-84. [PMID: 11893585 DOI: 10.1152/ajpheart.00739.2001] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Reduced activity of endothelial nitric oxide (NO) may be involved in thrombus formation on atherosclerotic plaques, a major cause of acute coronary syndrome. However, mechanisms of such increase in arterial thrombogenecity have not been fully understood. We previously reported that long-term inhibition of NO synthesis by administration of N(G)-nitro-L-arginine methyl ester (L-NAME) causes hypertension and activates vascular tissue angiotensin-converting enzyme (ACE) activity. We used this model to investigate the mechanism by which long-term impairment of NO activity increases arterial thrombogenecity. We observed cyclic flow variations (CFVs), a reliable marker of platelet thrombi, after the production of stenosis of the carotid artery in rats treated with L-NAME for 4 wk. The thrombin antagonist argatroban suppressed the CFVs. The CFVs were detected in rats receiving L-NAME plus hydralazine but not in rats receiving L-NAME plus an ACE inhibitor (imidapril). Treatment with the ACE inhibitor imidapril, but not with hydralazine, prevented L-NAME-induced increases in carotid arterial ACE activity and attenuated tissue factor expression. These results suggest that long-term inhibition of endothelial NO synthesis may increase arterial thrombogenecity at least in part through angiotensin II-induced induction of tissue factor and the resultant thrombin generation. These data provide a new insight as to how endothelial NO exhibits antithrombogenic properties of the endothelium.
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Affiliation(s)
- Mayuko Kubo-Inoue
- Department of Cardiovascular Medicine, Graduate School of Medical Science, Kyushu University, Fukuoka 812-8582, Japan
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92
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Sasaki KI, Murohara T, Ikeda H, Sugaya T, Shimada T, Shintani S, Imaizumi T. Evidence for the importance of angiotensin II type 1 receptor in ischemia-induced angiogenesis. J Clin Invest 2002. [DOI: 10.1172/jci0213055] [Citation(s) in RCA: 96] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
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93
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Sasaki K, Murohara T, Ikeda H, Sugaya T, Shimada T, Shintani S, Imaizumi T. Evidence for the importance of angiotensin II type 1 receptor in ischemia-induced angiogenesis. J Clin Invest 2002; 109:603-11. [PMID: 11877468 PMCID: PMC150887 DOI: 10.1172/jci13055] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023] Open
Abstract
The role of the renin-angiotensin system (RAS) in angiogenesis is little known. Here, we show that the angiotensin II (ATII) type 1 (AT1) receptor plays an important role in ischemia-induced angiogenesis. Well-developed collateral vessels and angiogenesis were observed in wild-type (WT) mice in response to hindlimb ischemia, whereas these responses were reduced in ATII type 1a receptor knockout (AT1a(-/-)) mice. Ischemia-induced angiogenesis was also impaired in WT mice treated with the AT1 receptor blocker TCV-116. These effects were not due to reduced systemic blood pressure (SBP), because hydralazine treatment preserved angiogenesis in WT mice although it reduced SBP to a level similar to that of AT1a(-/-) mice. Infiltration of inflammatory mononuclear cells (MNCs), including macrophages and T lymphocytes, was suppressed in the ischemic tissues of AT1a(-/-) mice compared with WT mice. Double immunofluorescence staining revealed that infiltrated macrophages and T lymphocytes expressed VEGF, and the expression of VEGF and monocyte chemoattractant protein-1 was also decreased in AT1a(-/-). Finally, the impaired angiogenesis in AT1a(-/-) mice was rescued by intramuscular transplantation of MNCs obtained from WT mice, further indicating the importance of MNC infiltration in ischemia-induced angiogenesis. Thus, the ATII--AT1 receptor pathway promotes early angiogenesis by supporting inflammatory cell infiltration and angiogenic cytokine expression.
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MESH Headings
- Angiotensin Receptor Antagonists
- Animals
- Blood Pressure/drug effects
- Blood Pressure/physiology
- Capillaries/pathology
- Chemokine CCL2/physiology
- Endothelial Growth Factors/physiology
- Hindlimb/blood supply
- Hydralazine/pharmacology
- Imidazoles/pharmacology
- Inflammation/etiology
- Inflammation/pathology
- Ischemia/complications
- Ischemia/physiopathology
- Leukocytes, Mononuclear/pathology
- Leukocytes, Mononuclear/transplantation
- Lymphokines/physiology
- Male
- Mice
- Mice, Inbred C57BL
- Mice, Knockout
- Neovascularization, Pathologic/etiology
- Neovascularization, Pathologic/physiopathology
- Pyridines/pharmacology
- Receptor, Angiotensin, Type 1
- Receptors, Angiotensin/deficiency
- Receptors, Angiotensin/genetics
- Receptors, Angiotensin/physiology
- Vascular Endothelial Growth Factor A
- Vascular Endothelial Growth Factors
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Affiliation(s)
- Ken Sasaki
- The Cardiovascular Research Institute, and Department of Internal Medicine III, Kurume University School of Medicine, Kurume, Japan
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94
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Halkin A, Keren G. Potential indications for angiotensin-converting enzyme inhibitors in atherosclerotic vascular disease. Am J Med 2002; 112:126-34. [PMID: 11835951 DOI: 10.1016/s0002-9343(01)01001-4] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Angiotensin-converting enzyme (ACE) inhibitors are well established as first-line therapy for patients with left ventricular dysfunction, diabetic patients with hypertension or renal disease, and patients recovering from myocardial infarction. Angiotensin II and bradykinin regulate cellular proliferation, inflammation, and endothelial function, thus playing an important role in the pathogenesis of atherosclerosis. A large body of experimental evidence reporting that ACE inhibitors limit these effects has formed the rationale for major clinical trials of these drugs in the management of atherosclerotic vascular disease. The first trial to be completed demonstrated that ACE inhibition improves the prognosis of patients who have, or are at risk of, atherosclerotic vascular disease, independent of its effects on left ventricular function and hypertension. Expanding the indications for ACE inhibitors is now evidence driven, although the choice of agent for these new indications remains to be determined by further research.
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Affiliation(s)
- Amir Halkin
- Department of Cardiology, Tel Aviv Sourasky Medical Center and the Sackler School of Medicine, Tel Aviv University, Tel Aviv, Israel
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95
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Berry C, Touyz R, Dominiczak AF, Webb RC, Johns DG. Angiotensin receptors: signaling, vascular pathophysiology, and interactions with ceramide. Am J Physiol Heart Circ Physiol 2001; 281:H2337-65. [PMID: 11709400 DOI: 10.1152/ajpheart.2001.281.6.h2337] [Citation(s) in RCA: 183] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Angiotensin II (ANG II) is a pleiotropic vasoactive peptide that binds to two distinct receptors: the ANG II type 1 (AT(1)) and type 2 (AT(2)) receptors. Activation of the renin-angiotensin system (RAS) results in vascular hypertrophy, vasoconstriction, salt and water retention, and hypertension. These effects are mediated predominantly by AT(1) receptors. Paradoxically, other ANG II-mediated effects, including cell death, vasodilation, and natriuresis, are mediated by AT(2) receptor activation. Our understanding of ANG II signaling mechanisms remains incomplete. AT(1) receptor activation triggers a variety of intracellular systems, including tyrosine kinase-induced protein phosphorylation, production of arachidonic acid metabolites, alteration of reactive oxidant species activities, and fluxes in intracellular Ca(2+) concentrations. AT(2) receptor activation leads to stimulation of bradykinin, nitric oxide production, and prostaglandin metabolism, which are, in large part, opposite to the effects of the AT(1) receptor. The signaling pathways of ANG II receptor activation are a focus of intense investigative effort. We critically appraise the literature on the signaling mechanisms whereby AT(1) and AT(2) receptors elicit their respective actions. We also consider the recently reported interaction between ANG II and ceramide, a lipid second messenger that mediates cytokine receptor activation. Finally, we discuss the potential physiological cross talk that may be operative between the angiotensin receptor subtypes in relation to health and cardiovascular disease. This may be clinically relevant, inasmuch as inhibitors of the RAS are increasingly used in treatment of hypertension and coronary heart disease, where activation of the RAS is recognized.
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Affiliation(s)
- C Berry
- Department of Medicine and Therapeutics, Western Infirmary, University of Glasgow, G11 6NT Glasgow, United Kingdom.
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96
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Affiliation(s)
- U Landmesser
- Department of Medicine, Emory University School of Medicine and the Atlanta Veterans Administration Hospital, Atlanta, Georgia 30322, USA
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97
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Abstract
The endothelium produces a number of vasodilator and vasoconstrictor substances that not only regulate vasomotor tone, but also the recruitment and activity of inflammatory cells and the propensity towards thrombosis. Endothelial vasomotor function is a convenient way to assess these other functions, and is related to the long-term risk of cardiovascular disease. Lipids (particularly low density lipoprotein cholesterol) and oxidant stress play a major role in impairing these functions, by reducing the bioavailability of nitric oxide and activating pro-inflammatory signalling pathways such as nuclear factor kappa B. Biomechanical forces on the endothelium, including low shear stress from disturbed blood flow, also activate the endothelium increasing vasomotor dysfunction and promoting inflammation by upregulating pro-atherogenic genes. In contrast, normal laminar shear stress promotes the expression of genes that may protect against atherosclerosis. The sub-cellular structure of endothelial cells includes caveolae that play an integral part in regulating the activity of endothelial nitric oxide synthase. Low density lipoprotein cholesterol and oxidant stress impair caveolae structure and function and adversely affect endothelial function. Lipid-independent pathways of endothelial cell activation are increasingly recognized, and may provide new therapeutic targets. Endothelial vasoconstrictors, such as endothelin, antagonize endothelium-derived vasodilators and contribute to endothelial dysfunction. Some but not all studies have linked certain genetic polymorphisms of the nitric oxide synthase enzyme to vascular disease and impaired endothelial function. Such genetic heterogeneity may nonetheless offer new insights into the variability of endothelial function.
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Affiliation(s)
- S Kinlay
- Cardiovascular Division, Brigham and Women's Hospital, Boston, Massachusetts 02115, USA.
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98
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Quiroz Y, Pons H, Gordon KL, Rincón J, Chávez M, Parra G, Herrera-Acosta J, Gómez-Garre D, Largo R, Egido J, Johnson RJ, Rodríguez-Iturbe B. Mycophenolate mofetil prevents salt-sensitive hypertension resulting from nitric oxide synthesis inhibition. Am J Physiol Renal Physiol 2001; 281:F38-47. [PMID: 11399644 DOI: 10.1152/ajprenal.2001.281.1.f38] [Citation(s) in RCA: 135] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Recent studies have suggested that subtle microvascular and tubulointerstitial injury in the kidney can cause salt-sensitive hypertension. To test this hypothesis, we determined whether the mild renal disease induced by transient blockade of nitric oxide (NO) synthesis would result in salt-sensitive hypertension and whether prevention of the renal injury by coadministration of the immunosuppressive agent mycophenolate mofetil (MMF) would block the development of salt sensitivity. N(omega)-nitro-L-arginine-methyl ester (L-NAME; 70 mg/100 ml in the drinking water) was administered for 3 wk to rats with or without MMF (30 mg x kg(-1) x day(-1) by gastric gavage), followed by a 1-wk "washout" period in which the MMF was continued, which was followed in turn by placement on a high-salt (4% NaCl) diet for an additional 4 wk. Renal histology was examined at 3 and 8 wk, and blood pressure was measured serially. L-NAME treatment resulted in acute hypertension and the development of mild renal injury. During the washout period, blood pressure returned to normal, only to return to the hypertensive range on exposure of the animals to a high-salt diet. MMF treatment prevented the development of hypertension in response to a high-salt diet. This correlated with the ability of MMF to inhibit specific aspects of the renal injury, including the development of segmental glomerulosclerosis, the infiltration of T cells and ANG II-positive cells, and the thickening of afferent arterioles.
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MESH Headings
- Animals
- Blood Pressure/drug effects
- Body Weight/drug effects
- Glomerulosclerosis, Focal Segmental/chemically induced
- Glomerulosclerosis, Focal Segmental/pathology
- Hypertension/chemically induced
- Hypertension/prevention & control
- Immunosuppressive Agents/pharmacology
- Kidney/metabolism
- Kidney/pathology
- Lymphocytes/immunology
- Macrophages/immunology
- Male
- Mycophenolic Acid/analogs & derivatives
- Mycophenolic Acid/pharmacology
- NG-Nitroarginine Methyl Ester
- Nephritis, Interstitial/chemically induced
- Nephritis, Interstitial/immunology
- Nephritis, Interstitial/pathology
- Nitric Oxide Synthase/antagonists & inhibitors
- Rats
- Rats, Sprague-Dawley
- Receptor, Angiotensin, Type 1
- Receptor, Angiotensin, Type 2
- Receptors, Angiotensin/analysis
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Affiliation(s)
- Y Quiroz
- Renal Service and Department of Immunobiology (INBIOMED), Hospital Universitario de la Universidad del Zulia, Maracaibo 4001-A, Venezuela
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99
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Katoh M, Egashira K, Kataoka C, Usui M, Koyanagi M, Kitamoto S, Ohmachi Y, Takeshita A, Narita H. Regression by ACE inhibition of arteriosclerotic changes induced by chronic blockade of NO synthesis in rats. Am J Physiol Heart Circ Physiol 2001; 280:H2306-12. [PMID: 11299235 DOI: 10.1152/ajpheart.2001.280.5.h2306] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
We previously reported that chronic inhibition of nitric oxide (NO) synthesis with N(omega)-nitro-L-arginine methyl ester (L-NAME) induces vascular inflammation at week 1 and produces subsequent arteriosclerosis at week 4 and that cotreatment with an angiotensin-converting enzyme (ACE) inhibitor prevents such changes. In the present study, we tested the hypothesis that treatment with an ACE inhibitor after development of vascular inflammation could inhibit arteriosclerosis in rats. Wistar-Kyoto rats were randomized to four groups: the control group received no drugs, the 4wL-NAME group received L-NAME (100 mg x kg(-1) x day(-1)) for 4 wk, the 1wL + 3wNT group received L-NAME for 1 wk and no treatment for the subsequent 3 wk, and the 1wL + 3wACEI group received L-NAME for 1 wk and the ACE inhibitor imidapril (20 mg x kg(-1) x day(-1)) for the subsequent 3 wk. After 4 wk, we observed significant arteriosclerosis of the coronary artery (medial thickening and fibrosis) and increased cardiac ACE activity in the 1wL + 3wNT group as well as in the 4wL-NAME group, but not in the 1wL + 3wACEI group. In a separate study, we examined apoptosis formation and found that posttreatment with imidapril (20 mg x kg(-1) x day(-1)) or an ANG II AT1-receptor antagonist, CS-866 (5 mg x kg(-1) x day(-1)), induced apoptosis (TdT-mediated nick end-labeling) in monocytes and myofibroblasts appearing in the inflammatory lesions associated with a clear degradation in the heart (DNA electrophoresis). In conclusion, treatment with the ACE inhibitor after 1 wk of L-NAME administration inhibited arteriosclerosis by inducing apoptosis in the cells with inflammatory lesions in this study, suggesting that increased ANG II activity inhibited apoptosis of the cells with inflammatory lesions and thus contributed to the development of arteriosclerosis.
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Affiliation(s)
- M Katoh
- Discovery Research Laboratory, Tanabe Seiyaku Co., Ltd., Saitama 335-8055, Japan.
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100
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Berry C, Brosnan MJ, Fennell J, Hamilton CA, Dominiczak AF. Oxidative stress and vascular damage in hypertension. Curr Opin Nephrol Hypertens 2001; 10:247-55. [PMID: 11224701 DOI: 10.1097/00041552-200103000-00014] [Citation(s) in RCA: 115] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
Oxidative stress, a state of excessive reactive oxidative species activity, is associated with vascular disease states such as hypertension. In this review, we discuss the recent advances in the field of reactive oxidative species-mediated vascular damage in hypertension. These include the identification of redox-sensitive tyrosine kinases, the characterization of enzymatic sources of superoxide production in human blood vessels, and their relationship with vascular damage in atherosclerosis and hypertension. Finally, recent developments in the search for strategies to attenuate vascular oxidative stress are reviewed.
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Affiliation(s)
- C Berry
- The British Heart Foundation Blood Pressure Group, Department of Medicine and Therapeutics, University of Glasgow, Glasgow, UK
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