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Sung DJ, Park S, Noh HJ, Golpasandi S, Eun SH, Lee H, Kim B, Wie J, Seo MS, Park SW, Bae YM. Receptor-specific contributions of caveolae, PKC, and Src tyrosine kinase to serotonergic and adrenergic regulation of Kv channels and vasoconstriction. Life Sci 2023; 328:121903. [PMID: 37394095 DOI: 10.1016/j.lfs.2023.121903] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2023] [Revised: 06/28/2023] [Accepted: 06/28/2023] [Indexed: 07/04/2023]
Abstract
AIMS Caveolae are invaginated, Ω-shaped membrane structures. They are now recognized as portals for signal transduction of multiple chemical and mechanical stimuli. Notably, the contribution of caveolae has been reported to be receptor-specific. However, details of how they differentially contribute to receptor signaling remain unclear. MAIN METHODS Using isometric tension measurements, patch-clamping, and western blotting, we examined the contribution of caveolae and their related signaling pathways to serotonergic (5-HT2A receptor-mediated) and adrenergic (α1-adrenoceptor-mediated) signaling in rat mesenteric arteries. KEY FINDINGS Disruption of caveolae by methyl-β-cyclodextrin effectively blocked vasoconstriction mediated by the 5-HT2A receptor (5-HT2AR), but not by the α1-adrenoceptor. Caveolar disruption selectively impaired 5-HT2AR-mediated voltage-dependent K+ channel (Kv) inhibition, but not α1-adrenoceptor-mediated Kv inhibition. In contrast, both serotonergic and α1-adrenergic effects on vasoconstriction, as well as Kv currents, were similarly blocked by the Src tyrosine kinase inhibitor PP2. However, inhibition of protein kinase C (PKC) by either GO6976 or chelerythrine selectively attenuated the effects mediated by the α1-adrenoceptor, but not by 5-HT2AR. Disruption of caveolae decreased 5-HT2AR-mediated Src phosphorylation, but not α1-adrenoceptor-mediated Src phosphorylation. Finally, the PKC inhibitor GO6976 blocked Src phosphorylation by the α1-adrenoceptor, but not by 5-HT2AR. SIGNIFICANCE 5-HT2AR-mediated Kv inhibition and vasoconstriction are dependent on caveolar integrity and Src tyrosine kinase, but not on PKC. In contrast, α1-adrenoceptor-mediated Kv inhibition and vasoconstriction are not dependent on caveolar integrity, but rather on PKC and Src tyrosine kinase. Caveolae-independent PKC is upstream of Src activation for α1-adrenoceptor-mediated Kv inhibition and vasoconstriction.
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Affiliation(s)
- Dong Jun Sung
- Department of Sport and Health Studies, College of Biomedical and Health Science, Konkuk University, Chungju 27478, Republic of Korea; Sports Convergence Institute, Konkuk University, Chungju 27478, Republic of Korea; Center for Metabolic Diseases, Konkuk University, Chungju 27478, Republic of Korea; Research Institute for Biomedical & Health Science, Chungju 27478, Republic of Korea
| | - Solah Park
- Department of Physiology, KU Open Innovation Center, Research Institute of Medical Science, Konkuk University School of Medicine, Chungju 27478, Republic of Korea
| | - Hyun Ju Noh
- Department of Physiology, KU Open Innovation Center, Research Institute of Medical Science, Konkuk University School of Medicine, Chungju 27478, Republic of Korea
| | - Shadi Golpasandi
- Department of Physiology, KU Open Innovation Center, Research Institute of Medical Science, Konkuk University School of Medicine, Chungju 27478, Republic of Korea
| | - Seo Hyeon Eun
- Department of Physiology, KU Open Innovation Center, Research Institute of Medical Science, Konkuk University School of Medicine, Chungju 27478, Republic of Korea
| | - Hyeryeong Lee
- Department of Physiology, KU Open Innovation Center, Research Institute of Medical Science, Konkuk University School of Medicine, Chungju 27478, Republic of Korea
| | - Bokyung Kim
- Department of Physiology, KU Open Innovation Center, Research Institute of Medical Science, Konkuk University School of Medicine, Chungju 27478, Republic of Korea
| | - Jinhong Wie
- Department of Physiology, KU Open Innovation Center, Research Institute of Medical Science, Konkuk University School of Medicine, Chungju 27478, Republic of Korea
| | - Mi Seon Seo
- Department of Physiology, KU Open Innovation Center, Research Institute of Medical Science, Konkuk University School of Medicine, Chungju 27478, Republic of Korea
| | - Sang Woong Park
- Department of Emergency Medical Services, Eulji University, Seongnam 13135, Republic of Korea.
| | - Young Min Bae
- Department of Physiology, KU Open Innovation Center, Research Institute of Medical Science, Konkuk University School of Medicine, Chungju 27478, Republic of Korea.
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Contribution of the STAT Family of Transcription Factors to the Expression of the Serotonin 2B (HTR2B) Receptor in Human Uveal Melanoma. Int J Mol Sci 2022; 23:ijms23031564. [PMID: 35163491 PMCID: PMC8836204 DOI: 10.3390/ijms23031564] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2021] [Revised: 01/21/2022] [Accepted: 01/26/2022] [Indexed: 11/16/2022] Open
Abstract
Uveal melanoma (UM) remains the most common intraocular malignancy among diseases affecting the adult eye. The primary tumor disseminates to the liver in half of patients and leads to a 6 to 12-month survival rate, making UM a particularly aggressive type of cancer. Genomic analyses have led to the development of gene-expression profiles that can efficiently predict metastatic progression. Among these genes, that encoding the serotonin receptor 2B (HTR2B) represents the most discriminant from this molecular signature, its aberrant expression being the hallmark of UM metastatic progression. Recent evidence suggests that expression of HTR2B might be regulated through the Janus kinase/Signal Transducer and Activator of Transcription proteins (JAK/STAT) intracellular signalization pathway. However, little is actually known about the molecular mechanisms involved in the abnormally elevated expression of the HTR2B gene in metastatic UM and whether activated STAT proteins participates to this mechanism. In this study, we determined the pattern of STAT family members expressed in both primary tumors and UM cell-lines, and evaluated their contribution to HTR2B gene expression. Examination of the HTR2B promoter sequence revealed the presence of a STAT putative target site (5′-TTC (N)3 GAA3′) located 280 bp upstream of the mRNA start site that is completely identical to the high affinity binding site recognized by these TFs. Gene profiling on microarrays provided evidence that metastatic UM cell lines with high levels of HTR2B also express high levels of STAT proteins whereas low levels of these TFs are observed in non-metastatic UM cells with low levels of HTR2B, suggesting that STAT proteins contribute to HTR2B gene expression in UM cells. All UM cell lines tested were found to express their own pattern of STAT proteins in Western blot analyses. Furthermore, T142 and T143 UM cells responded to interleukins IL-4 and IL-6 by increasing the phosphorylation status of STAT1. Most of all, expression of HTR2B also considerably increased in response to both IL-4 and IL-6 therefore providing evidence that HTR2B gene expression is modulated by STAT proteins in UM cells. The binding of STAT proteins to the −280 HTR2B/STAT site was also demonstrated by electrophoretic mobility shift assay (EMSA) analyses and site-directed mutation of that STAT site also abolished both IL-4 and IL-6 responsiveness in in vitro transfection analyses. The results of this study therefore demonstrate that members from the STAT family of TFs positively contribute to the expression of HTR2B in uveal melanoma.
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Stojanović M, Prostran M, Radenković M. The enhancement of serotonin-induced contraction of rat femoral artery is mediated by angiotensin II release from intact endothelium. Arch Physiol Biochem 2019; 125:44-55. [PMID: 29429366 DOI: 10.1080/13813455.2018.1437185] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
We have performed an in vitro study on isolated intact or denuded femoral artery (FA) of healthy, diabetic, and/or rats submitted to the FA occlusion. The aim was to determine the contribution of endothelium and endothelial dysfunction (ED) on serotonin-induced action in FA. Further, the contribution of angiotensin II and cyclooxygenase products of arachidonic acid was investigated. A marker of ED, vWF was measured in animal serum. Serotonin induced contraction-dependent contraction of isolated FA, which was increased in preparations with endothelium. Pathological conditions such as endothelial denudation, nicotine-induced ED, diabetes or occlusion of FA reduced serotonin-induced contraction. Comparable reduction of serotonin-induced contraction was achieved after inhibition of AT1 receptors with losartan in isolated FA with intact endothelium. Our results demonstrate that angiotensin II contributes to the enhancement of serotonin-induced contraction of femoral arteries with intact endothelium. This increase is attenuated by endothelium removal, nicotine treatment, vascular occlusion, and/or hyperglycemia.
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Affiliation(s)
- Marko Stojanović
- a Department of Pharmacology, Clinical Pharmacology and Toxicology; Faculty of Medicine , University of Belgrade , Belgrade , Serbia
| | - Milica Prostran
- a Department of Pharmacology, Clinical Pharmacology and Toxicology; Faculty of Medicine , University of Belgrade , Belgrade , Serbia
| | - Miroslav Radenković
- a Department of Pharmacology, Clinical Pharmacology and Toxicology; Faculty of Medicine , University of Belgrade , Belgrade , Serbia
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Huhtinen A, Hongisto V, Laiho A, Löyttyniemi E, Pijnenburg D, Scheinin M. Gene expression profiles and signaling mechanisms in α 2B-adrenoceptor-evoked proliferation of vascular smooth muscle cells. BMC SYSTEMS BIOLOGY 2017; 11:65. [PMID: 28659168 PMCID: PMC5490158 DOI: 10.1186/s12918-017-0439-8] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/03/2016] [Accepted: 06/09/2017] [Indexed: 12/31/2022]
Abstract
BACKGROUND α2-adrenoceptors are important regulators of vascular tone and blood pressure. Regulation of cell proliferation is a less well investigated consequence of α2-adrenoceptor activation. We have previously shown that α2B-adrenoceptor activation stimulates proliferation of vascular smooth muscle cells (VSMCs). This may be important for blood vessel development and plasticity and for the pathology and therapeutics of cardiovascular disorders. The underlying cellular mechanisms have remained mostly unknown. This study explored pathways of regulation of gene expression and intracellular signaling related to α2B-adrenoceptor-evoked VSMC proliferation. RESULTS The cellular mechanisms and signaling pathways of α2B-adrenoceptor-evoked proliferation of VSMCs are complex and include redundancy. Functional enrichment analysis and pathway analysis identified differentially expressed genes associated with α2B-adrenoceptor-regulated VSMC proliferation. They included the upregulated genes Egr1, F3, Ptgs2 and Serpine1 and the downregulated genes Cx3cl1, Cav1, Rhoa, Nppb and Prrx1. The most highly upregulated gene, Lypd8, represents a novel finding in the VSMC context. Inhibitor library screening and kinase activity profiling were applied to identify kinases in the involved signaling pathways. Putative upstream kinases identified by two different screens included PKC, Raf-1, Src, the MAP kinases p38 and JNK and the receptor tyrosine kinases EGFR and HGF/HGFR. As a novel finding, the Src family kinase Lyn was also identified as a putative upstream kinase. CONCLUSIONS α2B-adrenoceptors may mediate their pro-proliferative effects in VSMCs by promoting the activity of bFGF and PDGF and the growth factor receptors EGFR, HGFR and VEGFR-1/2. The Src family kinase Lyn was also identified as a putative upstream kinase. Lyn is known to be expressed in VSMCs and has been identified as an important regulator of GPCR trafficking and GPCR effects on cell proliferation. Identified Ser/Thr kinases included several PKC isoforms and the β-adrenoceptor kinases 1 and 2. Cross-talk between the signaling mechanisms involved in α2B-adrenoceptor-evoked VSMC proliferation thus appears to involve PKC activation, subsequent changes in gene expression, transactivation of EGFR, and modulation of kinase activities and growth factor-mediated signaling. While many of the identified individual signals were relatively small in terms of effect size, many of them were validated by combining pathway analysis and our integrated screening approach.
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Affiliation(s)
- Anna Huhtinen
- Department of Pharmacology, Drug Development and Therapeutics, Institute of Biomedicine, University of Turku, Kiinamyllynkatu 10, FI-20520 Turku, Finland
- Unit of Clinical Pharmacology, Turku University Hospital, Turku, Finland
| | - Vesa Hongisto
- Toxicology Division, Misvik Biology Oy, Turku, Finland
| | - Asta Laiho
- Turku Centre for Biotechnology, University of Turku and Åbo Akademi University, Turku, Finland
| | - Eliisa Löyttyniemi
- Department of Biostatistics, Department of Clinical Medicine, University of Turku, Turku, Finland
| | - Dirk Pijnenburg
- PamGene International BV, Wolvenhoek 10, 5211HH s’Hertogenbosch, The Netherlands
| | - Mika Scheinin
- Department of Pharmacology, Drug Development and Therapeutics, Institute of Biomedicine, University of Turku, Kiinamyllynkatu 10, FI-20520 Turku, Finland
- Unit of Clinical Pharmacology, Turku University Hospital, Turku, Finland
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Zhou L, Wang N, Li H, Tong G, Yang J, Lai L, Pan H, Ye X, Huang J. SOCS1 gene promoter methylation status is associated with in-stent restenosis after percutaneous coronary intervention. Oncotarget 2017; 8:56959-56967. [PMID: 28915645 PMCID: PMC5593616 DOI: 10.18632/oncotarget.18398] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2017] [Accepted: 05/02/2017] [Indexed: 11/25/2022] Open
Abstract
Background Inflammation is involved in the development of In-stent restenosis (ISR) after percutaneous coronary intervention. We aimed to investigate the association between of suppressor of cytokine signaling-1 (SOCS1), a major negative regulator for inflammation, and the occurrence of ISR in Chinese patients. Methods We enrolled patients with coronary artery disease who underwent PCI with stenting. PCI procedures were performed successfully and a follow-up angiography was repeated 1 year later to determine ISR presence. Real-time quantitative reverse transcription polymerase chain reaction and methylation-specific polymerase chain reaction (MSP) was used for SOCS1 methylation status determination. Results There are a total of 187 patients had SOCS1 methylation while there are 275 had no methylated SOCS1. Patients with SOCS1 methylation have a higher inflammatory status. Of note, patients with SOCS1 methylation had a significantly lower SOCS1 mRNA levels compared to those without. Patients with ISR tend to have a significantly higher percentage of SOCS1 gene methylation (P<0.001). We next conducted the Binary logistic regression analyses to determine the correlation of SOCS1 with ISR, using demographic and clinical characteristics. Our data show that SOCS1 methylation is the only factors which are closely associated with ISR incidence. Patients with SOCS1 methylation are 5 times more likely to have ISR after successful PCI as opposed to those without SOCS1 methylation (P<0.001). Conclusion Our data suggest that blood SOCS1 gene promoter methylation status is closely associated with ISR occurrence, thus may be used as a marker to predict ISR.
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Affiliation(s)
- Liang Zhou
- Department of Cardiology, Hangzhou First People's Hospital, Nanjing Medical University Hangzhou Hospital, Hangzhou, 310006 China
| | - Ningfu Wang
- Department of Cardiology, Hangzhou First People's Hospital, Nanjing Medical University Hangzhou Hospital, Hangzhou, 310006 China
| | - Hong Li
- Department of Cardiology, Hangzhou First People's Hospital, Nanjing Medical University Hangzhou Hospital, Hangzhou, 310006 China
| | - Guoxin Tong
- Department of Cardiology, Hangzhou First People's Hospital, Nanjing Medical University Hangzhou Hospital, Hangzhou, 310006 China
| | - Jianmin Yang
- Department of Cardiology, Hangzhou First People's Hospital, Nanjing Medical University Hangzhou Hospital, Hangzhou, 310006 China
| | - Lei Lai
- Department of Cardiology, Hangzhou First People's Hospital, Nanjing Medical University Hangzhou Hospital, Hangzhou, 310006 China
| | - Hao Pan
- Department of Cardiology, Hangzhou First People's Hospital, Nanjing Medical University Hangzhou Hospital, Hangzhou, 310006 China
| | - Xianhua Ye
- Department of Cardiology, Hangzhou First People's Hospital, Nanjing Medical University Hangzhou Hospital, Hangzhou, 310006 China
| | - Jinyu Huang
- Department of Cardiology, Hangzhou First People's Hospital, Nanjing Medical University Hangzhou Hospital, Hangzhou, 310006 China
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7
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Cardiovascular remodeling and the peripheral serotonergic system. Arch Cardiovasc Dis 2017; 110:51-59. [DOI: 10.1016/j.acvd.2016.08.002] [Citation(s) in RCA: 36] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/24/2016] [Revised: 08/12/2016] [Accepted: 08/19/2016] [Indexed: 02/08/2023]
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Esteban V, Méndez-Barbero N, Jiménez-Borreguero LJ, Roqué M, Novensá L, García-Redondo AB, Salaices M, Vila L, Arbonés ML, Campanero MR, Redondo JM. Regulator of calcineurin 1 mediates pathological vascular wall remodeling. ACTA ACUST UNITED AC 2011; 208:2125-39. [PMID: 21930771 PMCID: PMC3182048 DOI: 10.1084/jem.20110503] [Citation(s) in RCA: 53] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Angiotensin-II–driven calcineurin activation and regulator of calcineurin-1 (Rcan-1) expression is required for pathological vascular remodeling in mice. Artery wall remodeling, a major feature of diseases such as hypertension, restenosis, atherosclerosis, and aneurysm, involves changes in the tunica media mass that reduce or increase the vessel lumen. The identification of molecules involved in vessel remodeling could aid the development of improved treatments for these pathologies. Angiotensin II (AngII) is a key effector of aortic wall remodeling that contributes to aneurysm formation and restenosis through incompletely defined signaling pathways. We show that AngII induces vascular smooth muscle cell (VSMC) migration and vessel remodeling in mouse models of restenosis and aneurysm. These effects were prevented by pharmacological inhibition of calcineurin (CN) or lentiviral delivery of CN-inhibitory peptides. Whole-genome analysis revealed >1,500 AngII-regulated genes in VSMCs, with just 11 of them requiring CN activation. Of these, the most sensitive to CN activation was regulator of CN 1 (Rcan1). Rcan1 was strongly activated by AngII in vitro and in vivo and was required for AngII-induced VSMC migration. Remarkably, Rcan1−/− mice were resistant to AngII-induced aneurysm and restenosis. Our results indicate that aneurysm formation and restenosis share mechanistic elements and identify Rcan1 as a potential therapeutic target for prevention of aneurysm and restenosis progression.
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Affiliation(s)
- Vanesa Esteban
- Department of Vascular Biology and Inflammation, Centro Nacional de Investigaciones Cardiovasculares (CNIC), E-28029 Madrid, Spain
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Beamish JA, He P, Kottke-Marchant K, Marchant RE. Molecular regulation of contractile smooth muscle cell phenotype: implications for vascular tissue engineering. TISSUE ENGINEERING PART B-REVIEWS 2011; 16:467-91. [PMID: 20334504 DOI: 10.1089/ten.teb.2009.0630] [Citation(s) in RCA: 282] [Impact Index Per Article: 21.7] [Reference Citation Analysis] [Abstract] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
The molecular regulation of smooth muscle cell (SMC) behavior is reviewed, with particular emphasis on stimuli that promote the contractile phenotype. SMCs can shift reversibly along a continuum from a quiescent, contractile phenotype to a synthetic phenotype, which is characterized by proliferation and extracellular matrix (ECM) synthesis. This phenotypic plasticity can be harnessed for tissue engineering. Cultured synthetic SMCs have been used to engineer smooth muscle tissues with organized ECM and cell populations. However, returning SMCs to a contractile phenotype remains a key challenge. This review will integrate recent work on how soluble signaling factors, ECM, mechanical stimulation, and other cells contribute to the regulation of contractile SMC phenotype. The signal transduction pathways and mechanisms of gene expression induced by these stimuli are beginning to be elucidated and provide useful information for the quantitative analysis of SMC phenotype in engineered tissues. Progress in the development of tissue-engineered scaffold systems that implement biochemical, mechanical, or novel polymer fabrication approaches to promote contractile phenotype will also be reviewed. The application of an improved molecular understanding of SMC biology will facilitate the design of more potent cell-instructive scaffold systems to regulate SMC behavior.
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Affiliation(s)
- Jeffrey A Beamish
- Department of Biomedical Engineering, Case Western Reserve University, Cleveland, Ohio 44106-7207, USA
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Zhang F, Sun AS, Yu LM, Wu Q, Gong QH. Effects of isorhynchophylline on angiotensin II-induced proliferation in rat vascular smooth muscle cells. J Pharm Pharmacol 2010. [DOI: 10.1211/jpp.60.12.0014] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
Abstract
Proliferation of vascular smooth muscle cells (VSMCs) is a crucial event in cardiovascular diseases. Isorhynchophylline, an alkaloid from a traditional Chinese medicine Gambirplant, has been used to treat cardiovascular diseases. The aim of this study was to investigate the effects of isorhynchophylline on angiotensin II (Ang II)-induced proliferation of rat VSMCs. VSMCs were isolated from rat artery and cultured for 14 days before experimentation. The effect of isorhynchophylline on Ang II-induced proliferation was evaluated by cell number, MTT assay and flow cytometry, and nitric oxide (NO) content and activity of NO synthase (NOS) were measured. The expression of proto-oncogene c-fos, osteopontin (OPN) and proliferating cell nuclear antigen (PCNA) mRNAs was measured by real-time RT-PCR. VSMC cultures were verified by morphology and immunostaining with α-smooth muscle actin. Isorhynchophylline (0.1–10.0 μM) was not toxic to VSMCs, but markedly decreased Ang II (1.0 μm)-enhanced cell number and MTT intensity, and blocked cell transition from G0/G1 to S phase. Furthermore, isorhynchophylline increased the NO content and NOS activity, and suppressed Ang II-induced over-expression of c-fos, OPN and PCNA. Thus, isorhynchophylline was effective against Ang-II induced cell proliferation, an effect that appears to be due, at least in part, to increased NO production, regulation of the cell cycle, and depressed expression of c-fos, OPN and PCNA related to VMSC proliferation.
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Affiliation(s)
- Feng Zhang
- Department of Pharmacology, Zunyi Medical College, Zunyi, 563000, China
| | - An-Sheng Sun
- Department of Pharmacology, Zunyi Medical College, Zunyi, 563000, China
| | - Li-Mei Yu
- Department of Pharmacology, Zunyi Medical College, Zunyi, 563000, China
| | - Qin Wu
- Department of Pharmacology, Zunyi Medical College, Zunyi, 563000, China
| | - Qi-Hai Gong
- Department of Pharmacology, Zunyi Medical College, Zunyi, 563000, China
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Sathishkumar K, Yallampalli U, Elkins R, Yallampalli C. Raf-1 kinase regulates smooth muscle contraction in the rat mesenteric arteries. J Vasc Res 2010; 47:384-98. [PMID: 20110729 DOI: 10.1159/000277726] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2009] [Accepted: 09/04/2009] [Indexed: 01/30/2023] Open
Abstract
We investigated the potential role of Raf-1 kinase in mesenteric arterial contraction. Inhibitors of Raf-1 kinase, GW5074, L779450 and ZM 336372 reversed phenylephrine (PE)-induced mesenteric vascular contraction. Studies in vivo in rats showed that GW5074 inhibited PE-induced increase in mean arterial pressure in adult female Sprague-Dawley rats. Isometric tension studies in mesenteric arteries of rats showed that GW5074 did not change the KCl-evoked contraction but significantly inhibited the contractions to PE, 5-HT, U46619, endothelin 1, angiotensin II and phorbol 12, 13-dibutyrate (PDBu). In mesenteric vascular smooth muscle cells (VSMCs), PE stimulated increase in Raf-1 phosphorylation which was inhibited by GW5074. Measurement of [Ca(2+)](i) with Fura-2 showed that GW5074-mediated inhibition of PE-induced contraction was not associated with decreases in [Ca(2+)](i). VSMCs treated with PE exhibited higher levels of the contractile proteins, p-MYPT1 and p-MLC(20), which was inhibited by GW5074. Similarly, PDBu induced increases in phosphorylation of Raf-1, MLC(20) and MYPT1 and this was inhibited by GW5074. However, GW5074 did not have any significant effect on PE/PDBu-induced MEK/ERK activation. The results indicate that Raf-1 kinase plays an important role in the regulation of vascular contractility through regulation of calcium sensitization.
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Affiliation(s)
- Kunju Sathishkumar
- Department of Obstetrics and Gynecology, University of Texas Medical Branch, Galveston, Tex. 77555-1062, USA
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Kanome T, Watanabe T, Nishio K, Takahashi K, Hongo S, Miyazaki A. Angiotensin II upregulates acyl-CoA:cholesterol acyltransferase-1 via the angiotensin II Type 1 receptor in human monocyte-macrophages. Hypertens Res 2009; 31:1801-10. [PMID: 18971559 DOI: 10.1291/hypres.31.1801] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Angiotensin II (Ang II) is known to accelerate the progression of macrophage-driven atherosclerotic lesions. Acyl-CoA:cholesterol acyltransferase-1 (ACAT1) converts intracellular free cholesterol into cholesterol ester (CE) for storage in lipid droplets, and promotes foam cell formation in atherosclerotic lesions. The present study explored the effect of Ang II on ACAT1 expression as a molecular mechanism of foam cell formation in primary cultured human monocyte-macrophages. Ang II significantly increased ACAT1 protein expression in a time- or concentration-dependent manner. Application of an Ang II type 1 (AT(1)) receptor agonist (L162313), but not an Ang II type 2 (AT(2)) receptor agonist (CGP42112A), mimicked the effects of Ang II treatment in inducing ACAT1 protein expression. ACAT activity and ACAT1 mRNA levels were also significantly increased by Ang II. Two-fold increases in ACAT1 protein expression and ACAT activity with Ang II treatment were completely inhibited by AT(1) receptor antagonists (candesartan, [Sar(1),Ile(8)]-Ang II), but not by an AT(2) receptor antagonist (PD123319). Treatment with a G-protein inactivator (GDP-beta-S), a c-Src tyrosine kinase inhibitor (PP2), a protein kinase C (PKC) inhibitor (rottlerin), or a mitogen activated protein kinase (MAPK) kinase inhibitor (PD98059) significantly reduced Ang II-induced ACAT1 protein expression. Macrophage foam cell formation assessed using acetylated low-density lipoprotein (LDL)-induced CE accumulation was significantly enhanced by Ang II, which was completely inhibited by treatment with candesartan. These results suggested that Ang II enhances foam cell formation by upregulating ACAT1 expression predominantly through the actions of AT(1) receptor via the G protein/c-Src/PKC/MAPK pathway in human monocyte-macrophages.
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Affiliation(s)
- Tomoko Kanome
- Department of Biochemistry, Showa University School of Medicine, 1-5-8 Hatanodai, Shinagawa-ku, Tokyo, Japan
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Son DJ, Lee HW, Shin HW, Lee JJ, Yoo HS, Kim TJ, Yun YP, Hong JT. Enhanced release of sphingosine-1-phosphate from hypercholesterolemic platelets: role in development of hypercholesterolemic atherosclerosis. Prostaglandins Leukot Essent Fatty Acids 2008; 78:383-90. [PMID: 18571912 DOI: 10.1016/j.plefa.2008.04.010] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/24/2007] [Revised: 04/30/2008] [Accepted: 04/30/2008] [Indexed: 11/27/2022]
Abstract
Although it is well known that sphingosine-1-phosphate (S1P), which induces many biological responses, is present in plasma and is mainly released from activated platelets, little is known whether the release of S1P is increased when platelets are activated in the hypercholesterolemic condition, and what are the roles of increased S1P generation in the development or progression of the atherosclerosis. Results show that 0.5% cholesterol diet for 16 weeks induces platelet hyperaggregability to low doses of agonists as well as development of hypercholesterolemic atherosclerosis in the rabbits. The generation and released level of S1P were significantly increased in the hypersensitized platelets and blood plasma in hypercholesterolemic rabbits. We also demonstrated that S1P increased VSMC proliferation via endothelial differentiation gene (EDG)-1 receptor dependent pathway. Our results indicate that release of S1P from activated platelets was increased by enhanced platelet sensitivity in hypercholesterolemia, which potentiated the ox-LDL-induced VSMC proliferation via EDG-1 receptor pathway.
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MESH Headings
- Animals
- Aorta/cytology
- Aorta, Thoracic/pathology
- Arachidonic Acid/pharmacology
- Atherosclerosis/etiology
- Atherosclerosis/metabolism
- Blood Platelets/drug effects
- Blood Platelets/metabolism
- Cell Proliferation/drug effects
- Cells, Cultured
- Cholesterol/blood
- Cholesterol, Dietary/administration & dosage
- Cholesterol, HDL/blood
- Cholesterol, LDL/blood
- Collagen/pharmacology
- Hypercholesterolemia/chemically induced
- Hypercholesterolemia/complications
- Hypercholesterolemia/metabolism
- Lipoproteins, LDL/pharmacology
- Lysophospholipids/blood
- Lysophospholipids/metabolism
- Lysophospholipids/pharmacology
- Male
- Muscle, Smooth, Vascular/cytology
- Myocytes, Smooth Muscle/cytology
- Myocytes, Smooth Muscle/drug effects
- Myocytes, Smooth Muscle/metabolism
- Platelet Aggregation/drug effects
- Rabbits
- Receptors, Lysosphingolipid/antagonists & inhibitors
- Receptors, Lysosphingolipid/metabolism
- Sphingosine/analogs & derivatives
- Sphingosine/blood
- Sphingosine/metabolism
- Sphingosine/pharmacology
- Thrombin/pharmacology
- Triglycerides/blood
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Affiliation(s)
- Dong Ju Son
- College of Pharmacy and CBITRC, Chungbuk National University, Cheongju, Chungbuk 361-763, Republic of Korea
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14
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Tamura A, Watanabe T, Shinozaki K, Kotoku M, Yano S, Kadota J. Comparison of sarpogrelate and ticlopidine in bare metal coronary stent implantation. Int J Cardiol 2008; 126:79-83. [PMID: 17507105 DOI: 10.1016/j.ijcard.2007.03.120] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/07/2006] [Revised: 02/19/2007] [Accepted: 03/30/2007] [Indexed: 10/23/2022]
Abstract
BACKGROUND The efficacy and safety of sarpogrelate, a selective 5-hydroxytryptamine receptor subtype 2A antagonist, have not yet been established in bare metal coronary stenting. Accordingly, we sought to clarify whether treatment with sarpogrelate is clinically useful in bare metal coronary stenting. METHODS A total of 450 patients who underwent successfully planned or unplanned bare metal coronary stenting were randomly divided into the following 2 groups: the sarpogrelate (300 mg/day) plus aspirin (100 mg/day) group (group S, n=225) and the ticlopidine (200 mg/day) plus aspirin (100 mg/day) group (group T, n=225). Either sarpogrelate or ticlopidine was administered for at least 4 weeks after the procedure. Follow-up coronary arteriography was performed at 6 months after the procedure. The primary endpoints were the incidence of adverse drug reactions requiring a withdrawal of treatment and the rate of binary restenosis. The secondary endpoint was the incidence of stent thrombosis. RESULTS The incidence of adverse drug reactions requiring a withdrawal of treatment was significantly lower in group S than in group T (0.44% vs 8%, p=0.002). The rate of binary restenosis did not differ significantly between groups S and T (16.9% vs 18.2%). In addition, the incidence of subacute stent thrombosis did not differ between groups S and T (0.44% vs 0.44%). CONCLUSIONS The incidence of adverse drug reactions requiring a withdrawal of treatment was significantly lower with sarpogrelate use than with ticlopidine use. The rate of binary restenosis and the incidence of subacute stent thrombosis did not differ between both drug groups.
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Affiliation(s)
- Akira Tamura
- Second Department of Internal Medicine, Oita University, Idaigaoka 1-1, Hasama-machi, Yufu, Oita 879-5593, Japan.
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15
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Pang H, Wen YY, Ma N, Wang YT, Shi L. Protective role of a novel erythrocyte-derived depressing factor on blood vessels of renovascular hypertensive rats. Clin Exp Pharmacol Physiol 2007; 34:393-8. [PMID: 17439406 DOI: 10.1111/j.1440-1681.2007.04561.x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
1. We have isolated a novel human erythrocyte-derived depressing factor (EDDF) that has a significant antihypertensive effect in various rat models of hypertension. The aim of the present study was to examine the mechanisms of action of EDDF on vascular function in two-kidney, one-clip (2K1C) renovascular hypertensive rats. 2. The EDDF was prepared from human erythrocytes. Experiments were performed in 18 male Wistar rats. The vascular ring perfusion assay and a two-photon laser scanning fluorescence microscope (TMP) were used to evaluate the vascular contractile response. The effects of EDDF on phenylephrine (PE)- and noradrenaline (NA)-induced vascular contraction were evaluated in 2K1C hypertensive rats. The proliferation and DNA synthesis in vascular smooth muscle cells (VSMC) were determined using the [3H]-TdR (thymidine) incorporation and 3-(4,5-dimethyl-2 thiazoyl)-2,5-diphenyl-2H-tetrazolium bromide (MTT) assays. Flow cytometry, reverse transcription-polymerase chain reaction and western blots were used to measure cell cycle and apoptotic profiles, platelet-derived growth factor (PDGF)-A expression and the activity of extracellular signal-regulated kinase (ERK)-1/2, as well as the expression of cyclin D1 and cyclin-dependent kinase (CDK) 4. 3. At 10(-5) g/mL, EDDF significantly decreased the PE- and NA-induced hypertensive vascular contraction. In addition, EDDF inhibited DNA synthesis in primary VSMC from 2K1C rats. The mRNA expression of PDGF-A in VSMC was twofold higher in 2K1C rats compared with control rats, whereas EDDF significantly inhibited the increment in PDGF-A mRNA expression. In addition, EDDF inhibited the phosphorylation of ERK1/2 and decreased the expression of cyclin D1 and CDK4; p21 (Cip1) levels were increased after treatment with EDDF. 4. In conclusion, EDDF inhibits VSMC proliferation in 2K1C rats through G0/G1 cell cycle arrest. The effects may be mediated, in part, by enhanced expression of p21 (Cip1) and the inhibition of ERK1/2 phosphorylation and the expression of cyclin D1/CDK4 and PDGF-A.
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MESH Headings
- Animals
- Aorta, Thoracic/drug effects
- Aorta, Thoracic/physiopathology
- Biological Factors/chemistry
- Biological Factors/pharmacology
- Blotting, Western
- Cell Cycle/drug effects
- Cyclin D1/genetics
- Cyclin D1/metabolism
- Cyclin-Dependent Kinase 4/genetics
- Cyclin-Dependent Kinase 4/metabolism
- Cyclin-Dependent Kinase Inhibitor p21/genetics
- Cyclin-Dependent Kinase Inhibitor p21/metabolism
- Dose-Response Relationship, Drug
- Erythrocytes/chemistry
- Humans
- Hypertension, Renovascular/pathology
- Hypertension, Renovascular/physiopathology
- Hypertension, Renovascular/prevention & control
- Male
- Microscopy, Fluorescence
- Mitogen-Activated Protein Kinase 3/antagonists & inhibitors
- Mitogen-Activated Protein Kinase 3/genetics
- Mitogen-Activated Protein Kinase 3/metabolism
- Muscle, Smooth, Vascular/drug effects
- Muscle, Smooth, Vascular/metabolism
- Muscle, Smooth, Vascular/pathology
- Norepinephrine/pharmacology
- Phenylephrine/pharmacology
- Phosphorylation/drug effects
- Platelet-Derived Growth Factor/genetics
- Platelet-Derived Growth Factor/metabolism
- RNA, Messenger/genetics
- RNA, Messenger/metabolism
- Rats
- Rats, Wistar
- Reverse Transcriptase Polymerase Chain Reaction
- Vasoconstriction/drug effects
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Affiliation(s)
- Huan Pang
- Department of Physiology, Institute of Basic Medical Sciences, Chinese Academy of Medical Sciences, School of Basic Medicine, Peking Union Medical College, Beijing, China
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16
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Martins RAP, Pearson RA. Control of cell proliferation by neurotransmitters in the developing vertebrate retina. Brain Res 2007; 1192:37-60. [PMID: 17597590 DOI: 10.1016/j.brainres.2007.04.076] [Citation(s) in RCA: 82] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2007] [Revised: 04/04/2007] [Accepted: 04/20/2007] [Indexed: 01/24/2023]
Abstract
In the developing vertebrate retina, precise coordination of retinal progenitor cell proliferation and cell-cycle exit is essential for the formation of a functionally mature retina. Unregulated or disrupted cell proliferation may lead to dysplasia, retinal degeneration or retinoblastoma. Both cell-intrinsic and -extrinsic factors regulate the proliferation of progenitor cells during CNS development. There is now growing evidence that in the developing vertebrate retina, both slow and fast neurotransmitter systems modulate the proliferation of retinal progenitor cells. Classic neurotransmitters, such as GABA (gamma-amino butyric acid), glycine, glutamate, ACh (acetylcholine) and ATP (adenosine triphosphate) are released, via vesicular or non-vesicular mechanisms, into the immature retinal environment. Furthermore, these neurotransmitters signal through functional receptors even before synapses are formed. Recent evidence indicates that the activation of purinergic and muscarinic receptors may regulate the cell-cycle machinery and consequently the expansion of the retinal progenitor pool. Interestingly, GABA and glutamate appear to have opposing roles, inducing retinal progenitor cell-cycle exit. In this review, we present recent findings that begin to elucidate the roles of neurotransmitters as regulators of progenitor cell proliferation at early stages of retinal development. These studies also raise several new questions, including how these neurotransmitters regulate specific cell-cycle pathways and the mechanisms by which retinal progenitor cells integrate the signals from neurotransmitters and other exogenous factors during vertebrate retina development.
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Affiliation(s)
- Rodrigo A P Martins
- Department of Developmental Neurobiology, St. Jude Children's Research Hospital, MS323, Memphis, TN 38105, USA.
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17
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Danielyan L, Lourhmati A, Verleysdonk S, Kabisch D, Proksch B, Thiess U, Umbreen S, Schmidt B, Gleiter CH. Angiotensin Receptor Type 1 Blockade in Astroglia Decreases Hypoxia-Induced Cell Damage and TNF Alpha Release. Neurochem Res 2007; 32:1489-98. [PMID: 17406976 DOI: 10.1007/s11064-007-9337-6] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2006] [Accepted: 03/16/2007] [Indexed: 12/25/2022]
Abstract
The present study investigated the role of angiotensin receptors (AT-R) in the survival and inflammatory response of astroglia upon hypoxic injury. Exposure of rat astroglial primary cultures (APC) to hypoxic conditions (HC) led to decreased viability of the cells and to a 3.5-fold increase in TNF-alpha release. AT-R type1 (AT1-R) antagonist losartan and its metabolite EXP3174 decrease the LDH release (by 36 +/- 9%; 45 +/- 6%) from APC under HC. Losartan diminished TNF-alpha release (by 40 +/- 15%) and the number of TUNEL-cells by 204 +/- 38% under HC, alone and together with angiotensin II (ATII), while EXP3174 was dependent on ATII for its effect on TNF-alpha. The AT2-R antagonist, PD123.319, did not influence the release of LDH and TNF-alpha under normoxic (NC) and HC. These data suggest that AT1-R may decrease the susceptibility of astrocytes to hypoxic injury and their propensity to release TNF-alpha. AT1-R antagonists may therefore be of therapeutic value during hypoxia-associated neurodegeneration.
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Affiliation(s)
- Lusine Danielyan
- Department of Clinical Pharmacology, University Hospital of Tuebingen, Otfried-Mueller Strasse 45, 72076 Tuebingen, Germany.
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18
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Li C, Xu Q. Mechanical stress-initiated signal transduction in vascular smooth muscle cells in vitro and in vivo. Cell Signal 2007; 19:881-91. [PMID: 17289345 DOI: 10.1016/j.cellsig.2007.01.004] [Citation(s) in RCA: 100] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2006] [Accepted: 01/08/2007] [Indexed: 12/29/2022]
Abstract
Increasing evidence has been demonstrated that hypertension-initiated abnormal biomechanical stress is strongly associated with cardio-/cerebrovascular diseases e.g. atherosclerosis, stroke, and heart failure, which is main cause of morbidity and mortality. How the cells in the cardiovascular system sense and transduce the extracellular physical stimuli into intracellular biochemical signals is a crucial issue for understanding the mechanisms of the disease development. Recently, collecting data derived from our and other laboratories showed that many kinds of molecules in the cells such as receptors, ion channels, caveolin, G proteins, cell cytoskeleton, kinases and transcriptional factors could serve as mechanoceptors directly or indirectly in response to mechanical stimulation implying that the activation of mechanoceptors represents a non-specific manner. The sensed signals can be further sorted and/or modulated by processing of the molecules both on the cell surface and by the network of intracellular signaling pathways resulting in a sophisticated and dynamic set of cues that enable cardiovascular cell responses. The present review will summarise the data on mechanotransduction in vascular smooth muscle cells and formulate a new hypothesis, i.e. a non-specific activation of mechanoceptors followed by a variety of signal cascade activation. The hypothesis could provide us some clues for exploring new therapeutic targets for the disturbed mechanical stress-initiated diseases such as hypertension and atherosclerosis.
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Affiliation(s)
- Chaohong Li
- Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, Guangdong 510080, China
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19
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Koroleva SV, Nikolaeva AA, Ashmarin IP. Interactions between dopamine, serotonin, and other reward factor. BIOL BULL+ 2006. [DOI: 10.1134/s106235900604008x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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20
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Saini HK, Takeda N, Goyal RK, Kumamoto H, Arneja AS, Dhalla NS. Therapeutic Potentials of Sarpogrelate in Cardiovascular Disease*. ACTA ACUST UNITED AC 2006; 22:27-54. [PMID: 14978517 DOI: 10.1111/j.1527-3466.2004.tb00130.x] [Citation(s) in RCA: 64] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
In view of the pivotal role of serotonin (5-HT) in a wide variety of cardiovascular disorders, extensive effort has been made to develop different types of 5-HT receptor antagonists for therapeutic use. On the basis of experimental studies, this article is focused on the potentials of sarpogrelate, a specific 5-HT2A receptor antagonist as an antiplatelet, antithrombotic, antiatherosclerotic and antianginal agent. The major effects of sarpogrelate are due to the inhibition of 5-HT-induced platelet aggregation and smooth muscle cell proliferation. This agent was found to attenuate the 5-HT-mediated increase in intracellular Ca2+ and ischemia-reperfusion injury in the heart. Sarpogrelate has been found to have beneficial effects in peripheral vascular disease, restenosis after coronary stenting, pulmonary hypertension, acute and chronic myocardial infarction.
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Affiliation(s)
- Harjot K Saini
- Institute of Cardiovascular Sciences, St. Boniface General Hospital Research Centre, Department of Physiology, University of Manitoba, 351 Tache Avenue, Winnipeg, Manitoba R2H 2A6, Canada
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21
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Suguro T, Watanabe T, Kanome T, Kodate S, Hirano T, Miyazaki A, Adachi M. Serotonin acts as an up-regulator of acyl-coenzyme A:cholesterol acyltransferase-1 in human monocyte-macrophages. Atherosclerosis 2005; 186:275-81. [PMID: 16157345 DOI: 10.1016/j.atherosclerosis.2005.08.007] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/26/2005] [Revised: 07/28/2005] [Accepted: 08/01/2005] [Indexed: 10/25/2022]
Abstract
Acyl-coenzyme A:cholesterol acyltransferase-1 (ACAT-1) converts intracellular free cholesterol into cholesterol ester for storage in lipid droplets and plays an important role in the formation of macrophage-derived foam cells in atherosclerotic lesions. Serotonin (5-HT), a potent vasoconstrictor that is released from activated platelets, increases uptake of oxidized low-density lipoprotein (LDL) by macrophages, leading to foam cell formation, and contributes to the development of atherosclerotic plaque. However, it is not yet known whether 5-HT affects ACAT-1 expression in human monocyte-macrophages as the molecular mechanism of enhanced foam cell formation by 5-HT remains unclear. We examined the effects of 5-HT on ACAT-1 expression during differentiation of cultured human monocytes into macrophages. Expression of ACAT-1 protein but not 5-HT2A receptor increased in a time-dependent manner. 5-HT increased ACAT activity in a concentration-dependent manner after 7 days in primary monocyte culture. Immunoblotting analysis showed that 5-HT at 10 microM increased ACAT-1 protein expression level by two-fold, and this effect was abolished completely by a 5-HT2A receptor antagonist (sarpogrelate), its major metabolite (M-1), a G protein inactivator (GDP-beta-S), a protein kinase C (PKC) inhibitor (rottlerin), a Src family inhibitor (PP2), or a mitogen-activated protein kinase (MAPK) kinase inhibitor (PD98059). Northern blotting analysis indicated that among the four ACAT-1 mRNA transcripts (2.8-, 3.6-, 4.3-, and 7.0-kb), the levels of the 2.8- and 3.6-kb transcripts were selectively up-regulated by approximately 1.7-fold by 5-HT (10 microM). The results of the present study suggested that 5-HT may play a crucial role in macrophage-derived foam cell formation by up-regulating ACAT-1 expression via the 5-HT2A receptor/G protein/c-Src/PKC/MAPK pathway, contributing to the progression of atherosclerotic plaque.
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Affiliation(s)
- Toshiaki Suguro
- First Department of Internal Medicine, Showa University School of Medicine, Tokyo 142-8666, Japan
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22
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Duan W, Yu Y, Zhang L. Antiatherogenic Effects of Phyllanthus Emblica Associated with Corilagin and its Analogue. YAKUGAKU ZASSHI 2005; 125:587-91. [PMID: 15997216 DOI: 10.1248/yakushi.125.587] [Citation(s) in RCA: 58] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Oxidized low-density lipoprotein (ox-LDL) is the main etiologic factor in atherogenesis, and antioxidants are accepted as effective treatment of atherosclerosis. The aim of this study was to clarify whether the mechanism of the antiatherogenic effects of the herb Phyllanthus Emblica, which is widely used to treat atherosclerosis-related diseases, is associated with ox-LDL via its compounds of soluble tannin, corilagin (beta-1-O-galloyl-3,6-(R)-hexahydroxydiphenoyl-d-glucose), and its analogue Dgg16 (1,6-di-O-galloyl-beta-d-glucose). Human umbilical vein endothelial cells, ECV-304, were incubated with ox-LDL (50 mg/l), treated with corilagin or Dgg16 at different doses (0.0001-0.1 mmol/l), and then incubated with monocytes. Malondialdehyde (MDA) in the culture media was determined and the number of monocytes adhering to ECV-304 cells was counted with cytometry. In another experiment, the rat vascular smooth muscular cells (VSMC) were incubated in media with or without ox-LDL (50 mg/l), and with corilagin or Dgg16 also at different doses (0.0001-0.1 mol/l), the proliferation of which was assayed with MTT. The results showed that both corilagin and Dgg16 were able to decrease MDA, prevented ECV-304 cells from being adhering to by monocytes, and inhibited VSMC proliferation activated by ox-LDL. The results suggest that the two compounds are effective in inhibiting the progress of atherosclerosis by alleviating oxidation injury or by inhibiting ox-LDL-induced VSMC proliferation, which may be promising mechanisms for treating atherosclerosis.
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Affiliation(s)
- Weigang Duan
- Jiangsu Center for Drug Screening, China Pharmaceutical University, Nanjing 210038, China
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23
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Toshiro M, Ueno T, Tanaka M, Oka H, Miyamotq T, Osajima K, Matsumoto K. Antiproliferative Action of an Angiotensin I-Converting Enzyme Inhibitory Peptide, Val-Tyr, via an L-Type Ca2+ Channel Inhibition in Cultured Vascular Smooth Muscle Cells. Hypertens Res 2005; 28:545-52. [PMID: 16231761 DOI: 10.1291/hypres.28.545] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Recent antihypertensive studies have demonstrated that small peptides with angiotensin I-converting enzyme (ACE) inhibitory activity had an ability to lower or to modulate a pressor blood pressure response in mild hypertensive subjects. However, the underlying mechanisms still remain unclear. Based on our previous finding that a small peptide, Val-Tyr (VY), was accumulated in the rat aorta and kidney as well as in the circulating blood system, we here investigated whether antihypertensive small peptides exert an antiproliferative effect on serum- or mitogen-induced human vascular smooth muscle cells (VSMCs). Treatment with some ACE inhibitory small peptides (VY, Ile-Trp [IW], and Ile-Val-Tyr [IVY]) had diverse effects on serum-stimulated VSMC proliferation that were independent of their ACE inhibitory activity, though only VY exerted a potent antiproliferative action. VY also showed a greater inhibition of WST-8 incorporation in response to angiotensin (Ang) II-stimulation than the other two small peptides. The attenuation of Ang II-stimulated WST-8 incorporation by VY was not affected by Ang II receptor antagonists (losartan and saralasin ([Sar1, Ile8]-Ang II)), indicating that the antiproliferative action of VY may not be due to the peptide's antagonistic effect against Ang II receptors. Treatment with VY had a significant inhibitory effect on the WST-8 incorporation induced by the stimulation of a voltage-gated L-type Ca2+ channel agonist, Bay K 8644. Even in the presence of a K+ channel blocker (paxillin) the inhibition was apparent, suggesting that VY inhibited the proliferation of VSMCs by serving as a natural L-type Ca2+ channel blocker, but not as a K+ channel agonist.
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MESH Headings
- 3-Pyridinecarboxylic acid, 1,4-dihydro-2,6-dimethyl-5-nitro-4-(2-(trifluoromethyl)phenyl)-, Methyl ester/pharmacology
- Angiotensin I/antagonists & inhibitors
- Angiotensin II/pharmacology
- Angiotensin-Converting Enzyme Inhibitors/pharmacology
- Calcium Channel Agonists/pharmacology
- Calcium Channel Blockers/pharmacology
- Calcium Channels, L-Type/metabolism
- Cell Division/drug effects
- Cells, Cultured
- Cytoskeletal Proteins/pharmacology
- Dipeptides/pharmacology
- Humans
- Muscle, Smooth, Vascular/cytology
- Muscle, Smooth, Vascular/drug effects
- Paxillin
- Phosphoproteins/pharmacology
- Potassium Channel Blockers/pharmacology
- Vasoconstrictor Agents/pharmacology
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Affiliation(s)
- Matsui Toshiro
- Division of Bioscience and Bioenvironmental Sciences, Faculty of Agriculture, Graduate School of Kyushu University, Fukuoka, Japan.
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24
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Banes AKL, Shaw SM, Tawfik A, Patel BP, Ogbi S, Fulton D, Marrero MB. Activation of the JAK/STAT pathway in vascular smooth muscle by serotonin. Am J Physiol Cell Physiol 2004; 288:C805-12. [PMID: 15601754 DOI: 10.1152/ajpcell.00385.2004] [Citation(s) in RCA: 70] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Serotonin (5-hydroxytryptamine, 5-HT) is a vasoconstrictor and mitogen whose levels are elevated in diabetes. Previous studies have shown the presence of 5-HT2A, 5-HT2B, and 5-HT1B receptors in vascular smooth muscle cells (VSMCs). There are currently no data regarding 5-HT2B and 5-HT1B receptor activation of the JAK/STAT pathway in VSMCs and resultant potential alterations in 5-HT signaling in diabetes. Therefore, we tested the hypothesis that 5-HT differentially activates the JAK/STAT pathway in VSMCs under conditions of normal (5 mM) and high (25 mM) glucose. Treatment of rat VSMCs with 5-HT (10(-6) M) resulted in time-dependent activation ( approximately 2-fold) of JAK2, JAK1, and STAT1, but not STAT3 (maximal at 5 min, returned to baseline by 30 min). The 5-HT2B receptor agonist BW723C86 and the 5-HT1B receptor agonist CGS12066A (10(-9)-10(-5) M, 5-min stimulation) did not activate the JAK/STAT pathway. Treatment with the 5-HT2A receptor antagonist ketanserin (10 nM) inhibited JAK2 activation by 5-HT. Treatment of streptozotocin-induced diabetic rats with ketanserin (5 mg.kg-1.day-1) reduced activation of JAK2 and STAT1 but not STAT3 in endothelium-denuded thoracic aorta in vivo. 5-HT (10(-6) M) treatment resulted in increased cell proliferation and increased DNA synthesis, which were inhibited by the JAK2 inhibitor AG490. Further studies with apocynin, diphenyleneiodonium chloride, catalase, and virally transfected superoxide dismutase had no effect at either glucose concentration on activation of the JAK/STAT pathway by 5-HT. Therefore, we conclude that 5-HT activates JAK2, JAK1, and STAT1 via the 5-HT2A receptors in a reactive oxygen species-independent manner under both normal and high glucose conditions.
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Affiliation(s)
- Amy K L Banes
- Vascular Biology Center, Medical College of Georgia, CB-3301, Augusta, GA 30912-2500, USA.
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25
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Ni W, Thompson JM, Northcott CA, Lookingland K, Watts SW. The serotonin transporter is present and functional in peripheral arterial smooth muscle. J Cardiovasc Pharmacol 2004; 43:770-81. [PMID: 15167270 DOI: 10.1097/00005344-200406000-00006] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
We tested the hypothesis that the 5-HT transporter (5-HTT) is present and functional in peripheral arterial smooth muscle. In aorta and mesenteric resistance arteries, real time RT-PCR and western analyses indicated the presence of 5-HTT mRNA and a 74 kDa 5-HTT protein. Immunohistochemistry localized the transporter to smooth muscle and endothelial cells. 5-HT and the metabolite 5-hydroxyindole acetic acid (5-HIAA) were detected in aorta, carotid, and superior mesenteric arteries using HPLC; the MAOA inhibitor pargyline significantly increased (over 400%) arterial 5-HT concentration. 5-HT was taken up by arteries in a time-dependent manner and uptake was independent of the endothelium, sympathetic nerves, and norepinephrine transporter. 5-HT-induced contraction of normal aorta was potentiated by the 5-HTT inhibitor fluvoxamine. A change in arterial 5-HTT function occurs in deoxycorticosterone (DOCA)-salt hypertension as the potency and threshold of 5-HT in contracting aorta from the DOCA-salt rat was increased by fluoxetine and fluvoxamine (1 micromol/L; DOCA fluvoxamine -log EC50 [mol/L] = 6.85 +/- 0.08, DOCA-control = 6.44 +/- 0.08); expression of transporter was significantly increased in aorta of DOCA salt rats (145% Sham). These studies show for the first time the presence of the 5-HTT in peripheral arterial smooth muscle and raise the question as to the function of the 5-HTT in regulating peripheral effects of 5-HT.
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Affiliation(s)
- Wei Ni
- Department of Pharmacology and Toxicology, Michigan State University, East Lansing 48824-1317, USA
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26
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Sundgren NC, Giraud GD, Stork PJS, Maylie JG, Thornburg KL. Angiotensin II stimulates hyperplasia but not hypertrophy in immature ovine cardiomyocytes. J Physiol 2003; 548:881-91. [PMID: 12626668 PMCID: PMC2342902 DOI: 10.1113/jphysiol.2003.038778] [Citation(s) in RCA: 72] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022] Open
Abstract
Rat and sheep cardiac myocytes become binucleate as they complete the 'terminal differentiation' process soon after birth and are not able to divide thereafter. Angiotensin II (Ang II) is known to stimulate hypertrophic changes in rodent cardiomyocytes under both in vivo and in vitro conditions via the AT1 receptor and intracellular extracellular regulated kinase (ERK) signalling cascade. We sought to develop culture methods for immature sheep cardiomyocytes in order to test the hypothesis that Ang II is a hypertrophic agent in the immature myocardium of the sheep. We isolated fetal sheep cardiomyocytes and cultured them for 96 h, added Ang II and phenylephrine (PE) for 48 h, and measured footprint area and proliferation (5-bromo-2'-deoxyuridine (BrdU) uptake) separately in mono- vs. binucleate myocytes. We found that neither Ang II nor PE changed the footprint area of mononucleated cells. PE stimulated an increase in footprint area of binucleate cells but Ang II did not. Ang II increased myocyte BrdU uptake compared to serum free conditions, but PE did not affect BrdU uptake. The MAP kinase kinase (MEK) inhibitor UO126 prevented BrdU uptake in Ang II-stimulated cells and prevented cell hypertrophy in PE-stimulated cells. This paper establishes culture methods for immature sheep cardiomyocytes and reports that: (1) Ang II is not a hypertrophic agent; (2) Ang II stimulates hyperplastic growth among mononucleate myocytes; (3) PE is a hypertrophic agent in binucleate myocytes; and (4) the ERK cascade is required for the proliferation effect of Ang II and the hypertrophic effect of PE.
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Affiliation(s)
- N C Sundgren
- Department of Physiology, Oregon Health and Science University, Portland, USA
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Doggrell SA. The role of 5-HT on the cardiovascular and renal systems and the clinical potential of 5-HT modulation. Expert Opin Investig Drugs 2003; 12:805-23. [PMID: 12720492 DOI: 10.1517/13543784.12.5.805] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
The main peripheral sources of 5-hydroxytryptamine (5-HT) are as a neurotransmitter and local hormone in the gastrointestinal tract, and stored in circulating platelets and pulmonary neuroepithelial bodies. 5-HT has been shown to have many possible physiological and pathophysiological roles on the cardiovascular and renal systems. Thus, 5-HT may contribute to valvular heart disease, coronary artery disease, pulmonary hypertension, pulmonary embolism, pre-eclampsia, peripheral vascular disease and diabetic nephropathy. Consequently, modulators of the 5-HT system have diverse clinical potential. For instance, selective 5-HT subtype 3 receptor (5-HT(3)) antagonists may have potential in the treatment of the pain associated with myocardial infarction. MCI-9042 (sarpogrelate) or other 5-HT(2A) antagonists may have clinical potential for the treatment of vasospastic angina, ischaemic heart disease, reperfusion injury and hindlimb ischaemia. Several modulators of 5-HT (5-HT transporter inhibitors, 5-HT(1B) and (2B) antagonists) may have potential alone or in combination in the treatment of pulmonary hypertension. In hypertension, agonists at the 5-HT(7) and antagonists at the 5-HT(2B) may reduce blood pressure, and in diabetes, sarpogrelate may protect against nephropathy.
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Affiliation(s)
- Sheila A Doggrell
- School of Biomedical Sciences, University of Queensland, QLD 4072, Australia.
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Hayashi T, Sumi D, Matsui-Hirai H, Fukatsu A, Arockia Rani P J, Kano H, Tsunekawa T, Iguchi A. Sarpogrelate HCl, a selective 5-HT2A antagonist, retards the progression of atherosclerosis through a novel mechanism. Atherosclerosis 2003; 168:23-31. [PMID: 12732383 DOI: 10.1016/s0021-9150(03)00054-6] [Citation(s) in RCA: 51] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
Although sarpogrelate HCl is widely used for the prevention of arterial thrombosis, its effect on atherosclerosis is unknown. Accordingly, we here investigated the effects of sarpogrelate HCl on a rabbit model of atherosclerosis. Male rabbits were fed a 0.5% cholesterol diet (HCD) (Gp 1), HCD with vitamin E (Gp 2), HCD with vitamin E and sarpogrelate (Gp 3), or HCD with sarpogrelate alone (Gp 4) for 8 weeks. The atherosclerotic area was decreased by feeding of vitamin E and sarpogrelate (16.9+/-2.0% in Gp 1 vs. 8.2+/-2.0% in Gp 3). Tone-related basal NO release was higher in Gps 3 and 4. Acetylcholine-induced relaxation tended to be improved in Gp 3. The amount of eNOS mRNA was increased in Gp 4, and aortic cyclic GMP concentration showed the same tendency. O(2)(-) release tended to be decreased in Gps 2 and 3. The matrix metalloproteinase-1 (MMP-1)-positive area was decreased, and the percentage ratio of cell numbers of smooth muscle cells/macrophages in the plaque was increased in Gp 3. The results demonstrated that sarpogrelate HCl retards the progression of atherosclerosis in rabbits, and that this effect is enhanced by concomitant administration of vitamin E. Although upregulation of eNOS may play a role as one of the underlying mechanisms, our results suggest that an additional mechanism-possibly involving the antiproliferative effects of sarpogrelate HCl on smooth muscle cells and macrophages-may also play an important role.
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MESH Headings
- Acetylcholine/administration & dosage
- Animals
- Antioxidants/therapeutic use
- Aorta, Thoracic/drug effects
- Aorta, Thoracic/pathology
- Aorta, Thoracic/physiopathology
- Biomarkers/blood
- Blood Proteins/metabolism
- Cholesterol, HDL/blood
- Coronary Artery Disease/drug therapy
- Coronary Artery Disease/etiology
- Coronary Artery Disease/metabolism
- Cyclic GMP/metabolism
- Disease Models, Animal
- Disease Progression
- Dose-Response Relationship, Drug
- Endothelium, Vascular/drug effects
- Endothelium, Vascular/pathology
- Endothelium, Vascular/physiopathology
- Hypercholesterolemia/drug therapy
- Hypercholesterolemia/etiology
- Hypercholesterolemia/metabolism
- Male
- Matrix Metalloproteinase 1/drug effects
- Matrix Metalloproteinase 1/metabolism
- Matrix Metalloproteinase 2/drug effects
- Matrix Metalloproteinase 2/metabolism
- Models, Cardiovascular
- Myocardial Contraction/drug effects
- Myocardial Contraction/physiology
- Myocytes, Smooth Muscle/drug effects
- Myocytes, Smooth Muscle/metabolism
- Nitric Oxide Synthase/drug effects
- Nitric Oxide Synthase Type II
- Nitric Oxide Synthase Type III
- RNA, Messenger/drug effects
- RNA, Messenger/metabolism
- Rabbits
- Serotonin Antagonists/therapeutic use
- Succinates/therapeutic use
- Treatment Outcome
- Vasodilator Agents/administration & dosage
- Vitamin E/therapeutic use
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Affiliation(s)
- Toshio Hayashi
- Department of Geriatrics, Nagoya University Graduate School of Medicine, 65 Tsuruma-cho, Showa-ku, Japan.
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Pakala R. Coagulation factor Xa synergistically interacts with serotonin in inducing vascular smooth muscle cell proliferation. ACTA ACUST UNITED AC 2003; 4:69-76. [PMID: 14581086 DOI: 10.1016/s1522-1865(03)00144-6] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
INTRODUCTION Initial events following vascular interventions include activation of platelets and coagulation cascade. Activated platelets release several vasoactive mediators including serotonin. Activation of coagulation cascade results in conversion of inactive zymogens such as factor X to its active form (factor Xa). So this study designed to examine the effect of factor Xa on rabbit vascular smooth muscle cell (VSMC) proliferation and its interaction with serotonin. METHODS Growth-arrested VSMCs were incubated in a serum-free medium with different concentrations of factor Xa with or without serotonin. VSMC proliferation was examined by increase in incorporation of [3H]thymidine into DNA and by increase in cell number. RESULTS Factor Xa and serotonin stimulated DNA synthesis in a dose-dependent manner. Factor Xa had a maximal effect at 100 nM (1180+/-110%) and serotonin at 50 microM (345+/-21%). When added together, at nonmitogenic concentrations, factor Xa (0.1 nM) and serotonin (1 micoM) synergistically induced DNA synthesis (312+/-12%). These increases in DNA synthesis were paralleled by an increase in cell number. Serine protease inhibitors, active site blockers and platelet-derived growth factor receptor tyrosine kinase inhibitor blocked the mitogenic effect of factor Xa and its interaction with serotonin. Similarly, serotonin type 2 receptor inhibitor and Gi-protein-coupled receptor inhibitor inhibited the mitogenic effect of serotonin and its interaction with factor Xa. When used in combination, they blocked the interaction between factor Xa and serotonin. CONCLUSION Coagulation factor Xa and serotonin are mitogenic to VSMCs and also function as amplification factors to each other, suggesting that inhibition of neointimal proliferation after vascular injury may require the combined use of multiple growth factor inhibitors to simultaneously block several critical cellular activation pathways.
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Affiliation(s)
- Rajbabu Pakala
- Division of Cardiology, Department of Internal Medicine, University of Texas Health Science Center-Medical School, Houston, TX 77030, USA.
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Watanabe T, Pakala R, Katagiri T, Benedict CR. Antioxidant N-acetylcysteine inhibits vasoactive agents-potentiated mitogenic effect of mildly oxidized LDL on vascular smooth muscle cells. Hypertens Res 2002; 25:311-5. [PMID: 12047048 DOI: 10.1291/hypres.25.311] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Mildly oxidized LDL (mox-LDL) has been shown to induce monocyte-endothelial interactions and vascular smooth muscle cell (VSMC) proliferation, key events in the formation of the atherosclerotic lesion. Growth factors and vasoactive peptides are also thought to play a major role in atherogenesis. We examined the interaction between mox-LDL and well-known vasoactive agents such as serotonin (5-HT), angiotensin II (Ang-II), endothelin-1 (ET-1), or urotensin II (U-II) in inducing DNA synthesis in VSMCs. Growth-arrested VSMCs were incubated with different concentrations of native LDL, mox-LDL, or highly oxidized LDL (ox-LDL) with 5-HT, Ang-II, ET-1, or U-II in the absence or presence of N-acetylcysteine (NAC), an intracellular free radical scavenger. DNA synthesis in VSMCs was examined by [3H]thymidine incorporation into cellular DNA. Mox-LDL and ox-LDL stimulated [3H]thymidine incorporation with a maximal effect at 5 microg/ml (211%, 154%), which values were significantly greater than that for native LDL (128%). 5-HT, Ang-II, ET-1, or U-II also stimulated [3H]thymidine incorporation in a dose-dependent manner. 5-HT had a maximal stimulatory effect at a concentration of 50 micromol/l (205%), Ang-II at 1.75 micromol/l (202%), ET-1 at 0.1 micromol/l (205%), and U-II at 0.05 micromol/l (161%). When added together, mox-LDL (100 ng/ml)-induced [3H]thymidine incorporation was potentiated by low concentrations of 5-HT (1 micromol/l), Ang-II (0.5 micromol/l), ET-1 (1 nmol/l), or U-II (10 nmol/l) (114% to 330%, 325%, 338%, or 345%, respectively). Synergistic interactions of mox-LDL with 5-HT, Ang-II, ET-1, or U-II were significantly inhibited by NAC (400 micromol/l). Our results suggest that mild oxidation of LDL may enhance its atherogenic potential and exert a synergistic interaction with vasoactive agents in inducing DNA synthesis via the generation of reactive oxygen species in VSMCs.
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Affiliation(s)
- Takuya Watanabe
- Third Department of Internal Medicine, Showa University School of Medicine, Tokyo, Japan
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