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Ruisanchez É, Dancs P, Kerék M, Németh T, Faragó B, Balogh A, Patil R, Jennings BL, Liliom K, Malik KU, Smrcka AV, Tigyi G, Benyó Z. Lysophosphatidic acid induces vasodilation mediated by LPA1 receptors, phospholipase C, and endothelial nitric oxide synthase. FASEB J 2013; 28:880-90. [PMID: 24249637 DOI: 10.1096/fj.13-234997] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
Lysophosphatidic acid (LPA) has been implicated as a mediator of several cardiovascular functions, but its potential involvement in the control of vascular tone is obscure. Here, we show that both LPA (18:1) and VPC31143 (a synthetic agonist of LPA1-3 receptors) relax intact mouse thoracic aorta with similar Emax values (53.9 and 51.9% of phenylephrine-induced precontraction), although the EC50 of LPA- and VPC31143-induced vasorelaxations were different (400 vs. 15 nM, respectively). Mechanical removal of the endothelium or genetic deletion of endothelial nitric oxide synthase (eNOS) not only diminished vasorelaxation by LPA or VPC31143 but converted it to vasoconstriction. Freshly isolated mouse aortic endothelial cells expressed LPA1, LPA2, LPA4 and LPA5 transcripts. The LPA1,3 antagonist Ki16425, the LPA1 antagonist AM095, and the genetic deletion of LPA1, but not that of LPA2, abolished LPA-induced vasorelaxation. Inhibition of the phosphoinositide 3 kinase-protein kinase B/Akt pathway by wortmannin or MK-2206 failed to influence the effect of LPA. However, pharmacological inhibition of phospholipase C (PLC) by U73122 or edelfosine, but not genetic deletion of PLCε, abolished LPA-induced vasorelaxation and indicated that a PLC enzyme, other than PLCε, mediates the response. In summary, the present study identifies LPA as an endothelium-dependent vasodilator substance acting via LPA1, PLC, and eNOS.
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Affiliation(s)
- Éva Ruisanchez
- 1Z.B., Institute of Human Physiology and Clinical Experimental Research, Semmelweis University, POB 448, H-1446 Budapest, Hungary.
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Wijesinghe DS, Chalfant CE. Systems-Level Lipid Analysis Methodologies for Qualitative and Quantitative Investigation of Lipid Signaling Events During Wound Healing. Adv Wound Care (New Rochelle) 2013; 2:538-548. [PMID: 24527363 DOI: 10.1089/wound.2012.0402] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2012] [Accepted: 04/14/2013] [Indexed: 01/06/2023] Open
Abstract
OBJECTIVE Accumulating evidence implicates a prominent role for lipid signaling molecules in the regulation of wound healing. These lipids regulate hemostasis, onset and resolution of inflammation, migration and proliferation cells, angiogenesis, epithelialization, and remodeling of collagen. The objective of this overview is to demonstrate the applicability of systems level lipid analyses to identify and quantify lipid involved in events leading to wound healing. APPROACH Current advances in liquid chromatography coupled to tandem mass spectrometry have provided the means for carrying out quantitative and qualitative analysis of lipids at a systems level. This emerging field is collectively referred to as lipidomics and its potential in wound healing research is largely ignored. RESULTS While comprehensive applications of lipidomics in wound healing are limited, studies carried out by the authors as well as others demonstrate distinct changes in the lipidome during the wound healing process. INNOVATION Until recently, investigations into lipids were limited to the study of a few lipids at a time. Lipidomics approaches provide the capability to quantitatively and qualitatively assay almost the full complement of lipid signaling circuits at the same time. This allows obtaining a system level understanding of changes to the entire lipidome during the wound healing process. CONCLUSION The technology provides promising approach to understanding new signaling pathways based on lipids involved in wound healing. The understanding gained from such studies has the potential for the development of novel lipid based treatment strategies to promote wound healing.
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Affiliation(s)
- Dayanjan S. Wijesinghe
- Research and Development, Hunter Holmes McGuire Veterans' Affairs Medical Center, Richmond, Virginia
- Department of Biochemistry and Molecular Biology, School of Medicine, Virginia Commonwealth University, Richmond, Virginia
- Virginia Commonwealth University Reanimation Engineering Science Center (VCURES); Virginia Commonwealth University, Richmond, Virginia
| | - Charles E. Chalfant
- Research and Development, Hunter Holmes McGuire Veterans' Affairs Medical Center, Richmond, Virginia
- Department of Biochemistry and Molecular Biology, School of Medicine, Virginia Commonwealth University, Richmond, Virginia
- Virginia Commonwealth University Reanimation Engineering Science Center (VCURES); Virginia Commonwealth University, Richmond, Virginia
- The Massey Cancer Center, Richmond, Virginia
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Uchida Y. Ceramide signaling in mammalian epidermis. Biochim Biophys Acta Mol Cell Biol Lipids 2013; 1841:453-62. [PMID: 24055887 DOI: 10.1016/j.bbalip.2013.09.003] [Citation(s) in RCA: 73] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2013] [Revised: 09/05/2013] [Accepted: 09/06/2013] [Indexed: 12/12/2022]
Abstract
Ceramide, the backbone structure of all sphingolipids, as well as a minor component of cellular membranes, has a unique role in the skin, by forming the epidermal permeability barrier at the extracellular domains of the outermost layer of the skin, the stratum corneum, which is required for terrestrial mammalian survival. In contrast to the role of ceramide in forming the permeability barrier, the signaling roles of ceramide and its metabolites have not yet been recognized. Ceramide and/or its metabolites regulate proliferation, differentiation, and apoptosis in epidermal keratinocytes. Recent studies have further demonstrated that a ceramide metabolite, sphingosine-1-phosphate, modulates innate immune function. Ceramide has already been applied to therapeutic approaches for treatment of eczema associated with attenuated epidermal permeability barrier function. Pharmacological modulation of ceramide and its metabolites' signaling can also be applied to cutaneous disease prevention and therapy. The author here describes the signaling roles of ceramide and its metabolites in mammalian cells and tissues, including the epidermis. This article is part of a Special Issue entitled The Important Role of Lipids in the Epidermis and their Role in the Formation and Maintenance of the Cutaneous Barrier. Guest Editors: Kenneth R. Feingold and Peter Elias.
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Affiliation(s)
- Yoshikazu Uchida
- Department of Dermatology, University of California, San Francisco, CA, USA; School of Medicine, University of California, San Francisco, CA, USA; Dermatology Service and Research Unit, Veterans Affairs Medical Center, San Francisco, CA, USA; Northern California Institute for Research and Education, San Francisco, CA, USA.
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Abu El-Asrar AM, Mohammad G, Nawaz MI, Siddiquei MM, Kangave D, Opdenakker G. Expression of lysophosphatidic acid, autotaxin and acylglycerol kinase as biomarkers in diabetic retinopathy. Acta Diabetol 2013; 50:363-71. [PMID: 22864860 DOI: 10.1007/s00592-012-0422-1] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/12/2012] [Accepted: 07/23/2012] [Indexed: 02/01/2023]
Abstract
The proinflammatory lysophosphatidic acid (LPA) is a potent activator of several transcriptional factors and signaling pathways and a potent modulator of genes involved in inflammation, angiogenesis and fibrosis. This study was conducted to measure the levels of LPA and LPA-producing enzymes, autotaxin (ATX) and acylglycerol kinase (AGK) in the vitreous fluid from patients with proliferative diabetic retinopathy (PDR) and to correlate their levels with clinical disease activity and the level of vascular endothelial growth factor (VEGF). In addition, we examined the expression of ATX, AGK and VEGF receptor-2 (VEGFR-2) in the retinas of diabetic rats. Vitreous samples from 42 PDR and 35 nondiabetic patients were studied by enzyme-linked immunosorbent assay. Vitreous samples and retinas of rats were examined by Western blot analysis. VEGF, LPA and AGK levels in vitreous samples from PDR patients were significantly higher than those in control patients without diabetes (p < 0.001 for all comparisons). ATX levels in PDR with active neovascularization and inactive PDR were significantly lower than those in nondiabetic patients (p = 0.045). Mean VEGF and AGK levels in PDR with active neovascularization were significantly higher than those in inactive PDR and nondiabetic patients (p < 0.001 for both comparisons). A significant correlation was observed between levels of VEGF and levels of AGK in PDR patients (r = 0.954; p < 0.001). Western blot analysis revealed a significant increase in the expression of AGK and VEGFR-2 in vitreous samples and the retinas of diabetic rats compared to nondiabetic controls, whereas ATX was significantly downregulated. Our findings suggest that ATX-AGK-LPA signaling axis might be an important player in the development and progression of diabetic retinopathy.
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Affiliation(s)
- Ahmed M Abu El-Asrar
- Department of Ophthalmology, College of Medicine, King Saud University, Riyadh, Saudi Arabia.
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Tatematsu S, Francis SA, Natarajan P, Rader DJ, Saghatelian A, Brown JD, Michel T, Plutzky J. Endothelial lipase is a critical determinant of high-density lipoprotein-stimulated sphingosine 1-phosphate-dependent signaling in vascular endothelium. Arterioscler Thromb Vasc Biol 2013; 33:1788-94. [PMID: 23723371 DOI: 10.1161/atvbaha.113.301300] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
OBJECTIVE In addition to an extensively characterized role of high-density lipoprotein (HDL) in reverse cholesterol transport, bioactive lipids bound to HDL can also exert diverse vascular effects. Despite this, integration of HDL action in the vasculature with pathways that metabolize HDL and release bioactive lipids has been much less explored. The effects of HDL on endothelial cells are mediated in part by HDL-associated sphingosine 1-phosphate (S1P), which binds to S1P1 receptors and promotes activation of endothelial NO synthase (eNOS) and the kinase Akt. In these studies, we characterized the role of endothelial lipase (EL) in the control of endothelial signaling and biology, including those mediated by HDL-associated S1P. APPROACH AND RESULTS HDL-induced angiogenesis in aortic rings from EL-deficient (EL(-/-)) mice was markedly decreased compared with wild-type controls. In cultured endothelial cells, small interfering RNA-mediated knockdown of EL abrogated HDL-promoted endothelial cell migration and tube formation. Small interfering RNA-mediated EL knockdown also attenuated HDL-induced phosphorylation of eNOS(1179) and Akt(473). S1P stimulation restored HDL-induced endothelial migration and Akt/eNOS phosphorylation that had been blocked by small interfering RNA-mediated EL knockdown. HDL-induced endothelial cell migration and Akt/eNOS phosphorylation were completely inhibited by the S1P1 antagonist W146 but not by the S1P3 antagonist CAY10444. CONCLUSIONS EL is a critical determinant of the effects of HDL on S1P-mediated vascular responses and acts on HDL to promote activation of S1P1, leading to Akt/eNOS phosphorylation and subsequent endothelial migration and angiogenesis. The role of EL in HDL-associated S1P effects provides new insights into EL action, the responses seen through EL and HDL interaction, and S1P signaling.
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Affiliation(s)
- Satoru Tatematsu
- Division of Cardiovascular Medicine, Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, MA 02115, USA
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Avraham-Davidi I, Grunspan M, Yaniv K. Lipid signaling in the endothelium. Exp Cell Res 2013; 319:1298-305. [PMID: 23328305 DOI: 10.1016/j.yexcr.2013.01.009] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2012] [Accepted: 01/07/2013] [Indexed: 12/16/2022]
Affiliation(s)
- Inbal Avraham-Davidi
- Department of Biological Regulation, Weizmann Institute of Science, Rehovot 76100, Israel
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Ren H, Panchatcharam M, Mueller P, Escalante-Alcalde D, Morris AJ, Smyth SS. Lipid phosphate phosphatase (LPP3) and vascular development. BIOCHIMICA ET BIOPHYSICA ACTA 2013; 1831:126-32. [PMID: 22835522 PMCID: PMC3683602 DOI: 10.1016/j.bbalip.2012.07.012] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/06/2012] [Revised: 07/15/2012] [Accepted: 07/16/2012] [Indexed: 01/12/2023]
Abstract
Lipid phosphate phosphatases (LPP) are integral membrane proteins with broad substrate specificity that dephosphorylate lipid substrates including phosphatidic acid, lysophosphatidic acid, ceramide 1-phosphate, sphingosine 1-phosphate, and diacylglycerol pyrophosphate. Although the three mammalian enzymes (LPP1-3) demonstrate overlapping catalytic activities and substrate preferences in vitro, the phenotypes of mice with targeted inactivation of the Ppap2 genes encoding the LPP enzymes reveal nonredundant functions. A specific role for LPP3 in vascular development has emerged from studies of mice lacking Ppap2b. A meta-analysis of multiple, large genome-wide association studies identified a single nucleotide polymorphism in PPAP2B as a novel predictor of coronary artery disease. In this review, we will discuss the evidence that links LPP3 to vascular development and disease and evaluate potential molecular mechanisms. This article is part of a Special Issue entitled Advances in Lysophospholipid Research.
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Affiliation(s)
- H Ren
- The Gill Heart Institute, Division of Cardiovascular Medicine, Lexington, KY 40536-0200, USA
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Ren Y, Guo L, Tang X, Apparsundaram S, Kitson C, Deguzman J, Fuentes ME, Coyle L, Majmudar R, Allard J, Truitt T, Hamid R, Chen Y, Qian Y, Budd DC. Comparing the differential effects of LPA on the barrier function of human pulmonary endothelial cells. Microvasc Res 2012; 85:59-67. [PMID: 23084965 DOI: 10.1016/j.mvr.2012.10.004] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2012] [Revised: 10/08/2012] [Accepted: 10/09/2012] [Indexed: 02/08/2023]
Abstract
Lysophosphatidic acid (LPA) is a class of bioactive lyso-phospholipid that mediates most of its biological effects through a family of G protein-coupled receptors of which six have been identified. The role of the LPA pathway in driving chronic lung diseases such as idiopathic pulmonary fibrosis (IPF) has gained considerable academic and industry attention. Modulation of the pulmonary artery endothelial barrier function by the LPA1 receptor has been shown to drive pulmonary fibrosis in murine models of disease. The purpose of this study was (i) to assess the effect of LPA on the barrier function of human pulmonary arterial (HPAEC) and microvascular (HMVEC) endothelial cells and (ii) to identify the LPA receptor subtype(s) responsible for changes in human pulmonary endothelial cell permeability using LPA receptor antagonists and siRNA technology. Analysis of the LPA receptor subtype expression demonstrated predominant expression of LPA2 and LPA6 receptor subtypes in both HPAECs and HMVECs. HPAECs also exhibit low expression of LPA1, LPA3, and LPA4 receptor subtypes. Treatment of cells with increasing concentrations of LPA caused loss of barrier function in HPAECs but not HMVECs, despite both cell types exhibiting very similar LPA receptor expression profiles. The LPA-mediated loss of barrier function in HPAECs appears to be independent of the LPA1 receptor and likely to be mediated via the LPA6 receptor although we cannot exclude an additional role for the LPA2 and LPA4 receptors in mediating these effects. These results suggest cell-specific mechanisms exist in human pulmonary endothelial cells to permit regulation of barrier function downstream of LPA receptors. More importantly, our data indicate that selective LPA1 receptor antagonism may be insufficient for therapeutic use in pulmonary diseases where impaired endothelial barrier function is related to disease initiation and progression.
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Affiliation(s)
- Yonglin Ren
- Inflammation Discovery Therapeutic Area, Hoffmann-La Roche Inc., Nutley, NJ 07110-1199, USA
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Sefcik LS, Petrie Aronin CE, Botchwey EA. Engineering vascularized tissues using natural and synthetic small molecules. Organogenesis 2012; 4:215-27. [PMID: 19337401 DOI: 10.4161/org.4.4.6963] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2008] [Accepted: 09/10/2008] [Indexed: 12/21/2022] Open
Abstract
Vascular growth and remodeling are complex processes that depend on the proper spatial and temporal regulation of many different signaling molecules to form functional vascular networks. The ability to understand and regulate these signals is an important clinical need with the potential to treat a wide variety of disease pathologies. Current approaches have focused largely on the delivery of proteins to promote neovascularization of ischemic tissues, most notably VEGF and FGF. Although great progress has been made in this area, results from clinical trials are disappointing and safer and more effective approaches are required. To this end, biological agents used for therapeutic neovascularization must be explored beyond the current well-investigated classes. This review focuses on potential pathways for novel drug discovery, utilizing small molecule approaches to induce and enhance neovascularization. Specifically, four classes of new and existing molecules are discussed, including transcriptional activators, receptor selective agonists and antagonists, natural product-derived small molecules, and novel synthetic small molecules.
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Affiliation(s)
- Lauren S Sefcik
- Department of Biomedical Engineering; and Department of Orthopaedic Surgery; University of Virginia; Charlottesville, Virginia USA; Center for Immunity, Inflammation and Regenerative Medicine (CIIR); University of Virginia; Charlottesville, Virginia USA
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Farahat WA, Wood LB, Zervantonakis IK, Schor A, Ong S, Neal D, Kamm RD, Asada HH. Ensemble analysis of angiogenic growth in three-dimensional microfluidic cell cultures. PLoS One 2012; 7:e37333. [PMID: 22662145 PMCID: PMC3360734 DOI: 10.1371/journal.pone.0037333] [Citation(s) in RCA: 84] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2011] [Accepted: 04/20/2012] [Indexed: 11/19/2022] Open
Abstract
We demonstrate ensemble three-dimensional cell cultures and quantitative analysis of angiogenic growth from uniform endothelial monolayers. Our approach combines two key elements: a micro-fluidic assay that enables parallelized angiogenic growth instances subject to common extracellular conditions, and an automated image acquisition and processing scheme enabling high-throughput, unbiased quantification of angiogenic growth. Because of the increased throughput of the assay in comparison to existing three-dimensional morphogenic assays, statistical properties of angiogenic growth can be reliably estimated. We used the assay to evaluate the combined effects of vascular endothelial growth factor (VEGF) and the signaling lipid sphingoshine-1-phosphate (S1P). Our results show the importance of S1P in amplifying the angiogenic response in the presence of VEGF gradients. Furthermore, the application of S1P with VEGF gradients resulted in angiogenic sprouts with higher aspect ratio than S1P with background levels of VEGF, despite reduced total migratory activity. This implies a synergistic effect between the growth factors in promoting angiogenic activity. Finally, the variance in the computed angiogenic metrics (as measured by ensemble standard deviation) was found to increase linearly with the ensemble mean. This finding is consistent with stochastic agent-based mathematical models of angiogenesis that represent angiogenic growth as a series of independent stochastic cell-level decisions.
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Affiliation(s)
- Waleed A Farahat
- Department of Mechanical Engineering, Massachusetts Institute of Technology (MIT), Cambridge, Massachusetts, United States of America.
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ε-Viniferin is more effective than its monomer resveratrol in improving the functions of vascular endothelial cells and the heart. Biosci Biotechnol Biochem 2012; 76:954-60. [PMID: 22738966 DOI: 10.1271/bbb.110975] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
The present study compared the effects of resveratrol and its dimer ε-viniferin on vascular endothelial cells (VECs) functions, and on the blood pressure and cardiac mass of spontaneously hypertensive rats (SHRs). Treatment of VECs with these compounds enhanced cell proliferation via nitric oxide generation and protected the cells from oxidative stress by suppressing increases in intracellular oxygen species. ε-Viniferin was more potent than resveratrol in most of these effects. ε-Viniferin, but not resveratrol inhibited angiotensin-converting enzyme activity in vitro. Three weeks of ε-viniferin treatment (5 mg/kg) reduced the systolic blood pressure and improved the whole cardiac mass and left ventricle mass indexes in SHRs. In contrast, resveratrol administration (2.5 mg/kg) failed to lower the blood pressure and significantly improve these mass indexes. These data suggest that ε-viniferin as well as resveratrol may be involved in protecting the functions of VECs and the heart.
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Abu El-Asrar AM, Missotten L, Geboes K. Expression of autotaxin and acylglycerol kinase in proliferative vitreoretinal epiretinal membranes. Acta Ophthalmol 2012; 90:e84-9. [PMID: 22103573 DOI: 10.1111/j.1755-3768.2011.02303.x] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
PURPOSE Lysophosphatidic acid (LPA)/LPA(1) receptor pathway is involved in inflammation, angiogenesis and fibrosis. This study was conducted to analyse the expression of LPA-producing enzymes, autotaxin (ATX) and acylglycerol kinase (AGK) and LPA(1) receptor, in proliferative diabetic retinopathy (PDR) and proliferative vitreoretinopathy (PVR) epiretinal membranes. METHODS Nine active and 13 inactive membranes from patients with PDR and 21 membranes from patients with PVR were studied by immunohistochemistry. RESULTS In PDR membranes, vascular endothelial cells expressed ATX and AGK in 16 and 19 membranes, respectively. Stromal cells expressed ATX and AGK in 19 and 22 membranes, respectively. Immunoreactivity for LPA(1) receptor was noted in vascular endothelial cells and stromal cells in the five membranes stained for LPA(1) receptor. Numbers of blood vessels and stromal cells expressing CD34, ATX and AGK were significantly higher in active membranes than in inactive membranes. Significant correlations were detected between number of blood vessels expressing the panendothelial cell marker CD34 and number of blood vessels and stromal cells expressing ATX and AGK. In PVR membranes, spindle-shaped myofibroblasts expressing α-smooth muscle actin co-expressed ATX, AGK and LPA(1) receptor. CONCLUSIONS The LPA/LPA(1) receptor pathway may be involved in inflammatory, angiogenic and fibrotic responses in proliferative vitreoretinal disorders.
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Affiliation(s)
- Ahmed M Abu El-Asrar
- Department of Ophthalmology, College of Medicine, King Saud University, Riyadh, Saudi Arabia.
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Abstract
INTRODUCTION Pharmacological mobilization has been exploited as a means to obtain hematopoietic stem progenitor cells (HSPCs) for hematopoietic reconstitution. HSPCs mobilized from bone marrow into peripheral blood (PB) are a preferred source of stem cells for transplantation, because they are easily accessible and evidence indicates that they engraft faster after transplantation than HSPCs directly harvested from bone marrow (BM) or umbilical cord blood (UCB). AREAS COVERED Since chemokine-chemokine receptor axes are involved in retention of HSPCs in the BM microenvironment, chemokine receptor agonists have been proposed as therapeutics to facilitate the mobilization process. These compounds include agonists of the CXCR4 receptor expressed on HSPCs (CTCE-0021 and ATI-2341) or chemokines binding to chemokine receptors expressed on granuclocytes and monocytes (e.g., CXCL2, also known as the growth-related oncogene protein-beta (Gro-β); CCL3, also known as macrophage inflammatory protein-1α (MIP-1α); or CXCL8, also known as IL-8) could be employed alone or in combination with other mobilizing agents (e.g., G-CSF or Plerixafor (AMD3100)). We discuss the current state of knowledge about chemokine receptor agonists and the rationale for their application in mobilization protocols. EXPERT OPINION Evidence is accumulating that CXCR4 receptor agonists could be employed alone or with other agents as mobilizing drugs. In particular they may provide an alternative for patients that are poor mobilizers.
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Affiliation(s)
- Mariusz Z Ratajczak
- University of Louisville, Stem Cell Institute at James Graham Brown Cancer Center, 500 S. Floyd Street, Room. 107, Louisville, KY 40202, USA.
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Hwang SH, Shin TJ, Choi SH, Cho HJ, Lee BH, Pyo MK, Lee JH, Kang J, Kim HJ, Park CW, Shin HC, Nah SY. Gintonin, newly identified compounds from ginseng, is novel lysophosphatidic acids-protein complexes and activates G protein-coupled lysophosphatidic acid receptors with high affinity. Mol Cells 2012; 33:151-62. [PMID: 22286231 PMCID: PMC3887723 DOI: 10.1007/s10059-012-2216-z] [Citation(s) in RCA: 96] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2011] [Revised: 11/30/2011] [Accepted: 12/02/2011] [Indexed: 11/27/2022] Open
Abstract
Recently, we isolated a subset of glycolipoproteins from Panax ginseng, that we designated gintonin, and demonstrated that it induced [Ca2+]i transients in cells via G protein-coupled receptor (GPCR) signaling pathway(s). However, active components responsible for Ca2+ mobilization and the corresponding receptor(s) were unknown. Active component(s) for [Ca2+]i transients of gintonin were analyzed by liquid chromatography-electrospray ionization-tandem mass spectrometry and ion-mobility mass spectrometry, respectively. The corresponding receptor(s)were investigated through gene expression assays. We found that gintonin contains LPA C18:2 and other LPAs. Proteomic analysis showed that ginseng major latex-like protein and ribonuclease-like storage proteins are protein components of gintonin. Gintonin induced [Ca2+]i transients in B103 rat neuroblastoma cells transfected with human LPA receptors with high affinity in order of LPA2 >LPA5 > LPA1 > LPA3 > LPA4. The LPA1/LPA3 receptor antagonist Ki16425 blocked gintonin action in cells expressing LPA1 or LPA3. Mutations of binding sites in the LPA3 receptor attenuated gintonin action. Gintonin acted via pertussis toxin (PTX)-sensitive and -insensitive G protein-phospholipase C (PLC)-inositol 1,4,5-trisphosphate (IP3)-Ca2+ pathways. However, gintonin had no effects on other receptors examined. In human umbilical vein endothelial cells (HUVECs) gintonin stimulated cell proliferation and migration. Gintonin stimulated ERK1/2 phosphorylation. PTX blocked gintonin-mediated migration and ERK1/2 phosphorylation. In PC12 cells gintonin induced morphological changes, which were blocked by Rho kinase inhibitorY-27632. Gintonin contains GPCR ligand LPAs in complexes with ginseng proteins and could be useful in the development of drugs targeting LPA receptors.
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Affiliation(s)
- Sung Hee Hwang
- Ginsentology Research Laboratory and Department of Physiology, and Bio/Molecular Informatics Center, College of Veterinary Medicine, Konkuk University, Seoul 143-701,
Korea
| | - Tae-Joon Shin
- Ginsentology Research Laboratory and Department of Physiology, and Bio/Molecular Informatics Center, College of Veterinary Medicine, Konkuk University, Seoul 143-701,
Korea
| | - Sun-Hye Choi
- Ginsentology Research Laboratory and Department of Physiology, and Bio/Molecular Informatics Center, College of Veterinary Medicine, Konkuk University, Seoul 143-701,
Korea
| | - Hee-Jung Cho
- Department of Veterinary Pharmacology and Toxicology, College of Veterinary Medicine, Konkuk University, Seoul 143-701,
Korea
| | - Byung-Hwan Lee
- Ginsentology Research Laboratory and Department of Physiology, and Bio/Molecular Informatics Center, College of Veterinary Medicine, Konkuk University, Seoul 143-701,
Korea
| | - Mi Kyung Pyo
- International Ginseng and Herb Research Institute, Geumsan 312-804,
Korea
| | - Jun-Ho Lee
- Ginsentology Research Laboratory and Department of Physiology, and Bio/Molecular Informatics Center, College of Veterinary Medicine, Konkuk University, Seoul 143-701,
Korea
| | - Jiyeon Kang
- Ginsentology Research Laboratory and Department of Physiology, and Bio/Molecular Informatics Center, College of Veterinary Medicine, Konkuk University, Seoul 143-701,
Korea
| | - Hyeon-Joong Kim
- Ginsentology Research Laboratory and Department of Physiology, and Bio/Molecular Informatics Center, College of Veterinary Medicine, Konkuk University, Seoul 143-701,
Korea
| | - Chan-Woo Park
- Ginsentology Research Laboratory and Department of Physiology, and Bio/Molecular Informatics Center, College of Veterinary Medicine, Konkuk University, Seoul 143-701,
Korea
| | - Ho-Chul Shin
- Department of Veterinary Pharmacology and Toxicology, College of Veterinary Medicine, Konkuk University, Seoul 143-701,
Korea
| | - Seung-Yeol Nah
- Ginsentology Research Laboratory and Department of Physiology, and Bio/Molecular Informatics Center, College of Veterinary Medicine, Konkuk University, Seoul 143-701,
Korea
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Cheng HY, Dong A, Panchatcharam M, Mueller P, Yang F, Li Z, Mills G, Chun J, Morris AJ, Smyth SS. Lysophosphatidic acid signaling protects pulmonary vasculature from hypoxia-induced remodeling. Arterioscler Thromb Vasc Biol 2011; 32:24-32. [PMID: 22015657 DOI: 10.1161/atvbaha.111.234708] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
OBJECTIVE Lysophosphatidic acid (LPA) is a bioactive lipid molecule produced by the plasma lysophospholipase D enzyme autotaxin that is present at ≥100 nmol/L in plasma. Local administration of LPA promotes systemic arterial remodeling in rodents. To determine whether LPA contributes to remodeling of the pulmonary vasculature, we examined responses in mice with alterations in LPA signaling and metabolism. METHODS AND RESULTS Enpp2(+/-) mice, which are heterozygous for the autotaxin-encoding gene and which have reduced expression of autotaxin/lysophospholipase D and approximately half normal plasma LPA, were hyperresponsive to hypoxia-induced vasoconstriction and remodeling, as evidenced by the development of higher right ventricular (RV) systolic pressure, greater decline in peak flow velocity across the pulmonary valve, and a higher percentage of muscularized arterioles. Mice lacking LPA(1) and LPA(2), 2 LPA receptors abundantly expressed in the vasculature, also had enhanced hypoxia-induced pulmonary remodeling. With age, Lpar1(-/-)2(-/-) mice spontaneously developed elevated RV systolic pressure and RV hypertrophy that was not observed in Lpar1(-/-) mice or Lpar2(-/-) mice. Expression of endothelin-1, a potent vasoconstrictor, was elevated in lungs of Lpar1(-/-)2(-/-) mice, and expression of endothelin(B) receptor, which promotes vasodilation and clears endothelin, was reduced in Enpp2(+/-) and Lpar1(-/-)2(-/-) mice. CONCLUSIONS Our findings indicate that LPA may negatively regulate pulmonary vascular pressure through LPA(1) and LPA(2) receptors and that in the absence of LPA signaling, upregulation in the endothelin system favors remodeling.
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Affiliation(s)
- Hsin-Yuan Cheng
- Division of Cardiovascular Medicine, Gill Heart Institute, University of Kentucky, Lexington, KY, USA
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66
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Cui MZ. Lysophosphatidic acid effects on atherosclerosis and thrombosis. ACTA ACUST UNITED AC 2011; 6:413-426. [PMID: 22162980 DOI: 10.2217/clp.11.38] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Lysophosphatidic acid (LPA) has been found to accumulate in high concentrations in atherosclerotic lesions. LPA is a bioactive phospholipid produced by activated platelets and formed during the oxidation of LDL. Accumulating evidence suggests that this lipid mediator may serve as an important risk factor for development of atherosclerosis and thrombosis. The role of LPA in atherogenesis is supported by the evidence that LPA: stimulates endothelial cells to produce adhesion molecules and chemoattractants; induces smooth muscle cells to produce inflammatory cytokines; stimulates smooth muscle cell dedifferentiation, proliferation, and migration; increases monocyte migration and decreases monocyte-derived cell emigration from the vessel wall; induces hypertension and vascular neointimal formation in vivo; and promotes plaque progression in a mouse atherosclerosis model. The role of LPA in thrombogenesis is supported by the evidence that LPA markedly induces the aggregation of platelets and the expression of tissue factor, which is the principal initiator of blood coagulation. Recent experimental data indicate that LPA is produced by specific enzymes and that LPA binds to and activates multiple G-protein-coupled receptors, leading to intracellular signaling. Therapeutics targeting LPA biosynthesis, metabolism and signaling pathways could be viable for prevention and treatment of atherosclerosis and thrombosis.
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Affiliation(s)
- Mei-Zhen Cui
- Department of Pathobiology, College of Veterinary Medicine, University of Tennessee, 2407 River Drive, Knoxville, TN 37996, USA
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67
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Kundu S, Sengupta S, Bhattacharyya A. EGFR upregulates inflammatory and proliferative responses in human lung adenocarcinoma cell line (A549), induced by lower dose of cadmium chloride. Inhal Toxicol 2011; 23:339-48. [DOI: 10.3109/08958378.2011.572931] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
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68
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Zrelli H, Matsuoka M, Kitazaki S, Araki M, Kusunoki M, Zarrouk M, Miyazaki H. Hydroxytyrosol induces proliferation and cytoprotection against oxidative injury in vascular endothelial cells: role of Nrf2 activation and HO-1 induction. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2011; 59:4473-4482. [PMID: 21438539 DOI: 10.1021/jf104151d] [Citation(s) in RCA: 88] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
Hydroxytyrosol (HT), a phenolic compound in olive oil and leaves, has been reported to prevent various human pathologies including cardiovascular diseases. This study investigated the effects of HT on proliferation and protection against oxidative stress-induced damage in vascular endothelial cells (VECs) and the molecular mechanism(s) involved. Treatment of VECs with HT increased cell proliferation, promoted wound repair, and protected cells against H(2)O(2) cytotoxicity through the activation of Akt and ERK1/2, but not p38 MAPK. HT increased the expression and nuclear translocation of nuclear factor-E2-related factor-2 (Nrf2). Nrf2 expression was attenuated by LY294002 and U0126, inhibitors of phosphatidylinositol-3-kinase and MEK1/2, respectively. Nrf2 siRNA decreased both proliferative and cytoprotective effects of HT and abrogated HO-1 induction. Moreover, HO-1 inhibition with HO-1 siRNA or zinc protoporphyrin IX significantly prevented HT-induced cell proliferation, cytoprotection, and reduction in intracellular reactive oxygen species (ROS), suggesting that HO-1 is involved in these HT functions. The findings demonstrate that HT positively regulates the antioxidant defense system in VECs through the activation of Nrf2 followed by cell proliferation and resistance to vascular injury. The present study provides a molecular basis for the contribution of HT in the Mediterranean diet to the prevention of cardiovascular diseases.
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Affiliation(s)
- Houda Zrelli
- Graduate School of Life and Environment Sciences, Alliance for Research on North Africa, University of Tsukuba, Tsukuba, Ibaraki, Japan
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69
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Soleimani R, Heytens E, Oktay K. Enhancement of neoangiogenesis and follicle survival by sphingosine-1-phosphate in human ovarian tissue xenotransplants. PLoS One 2011; 6:e19475. [PMID: 21559342 PMCID: PMC3084884 DOI: 10.1371/journal.pone.0019475] [Citation(s) in RCA: 144] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2011] [Accepted: 04/04/2011] [Indexed: 11/26/2022] Open
Abstract
Ovarian transplantation is one of the key approaches to restoring fertility in women who became menopausal as a result of cancer treatments. A major limitation of human ovarian transplants is massive follicular loss during revascularization. Here we investigated whether sphingosine-1-phosphate or its receptor agonists could enhance neoangiogenesis and follicle survival in ovarian transplants in a xenograft model. Human ovarian tissue xenografts in severe-combined-immunodeficient mice were treated with sphingosine-1-phosphate, its analogs, or vehicle for 1–10 days. We found that sphingosine-1-phosphate treatment increased vascular density in ovarian transplants significantly whereas FTY720 and SEW2871 had the opposite effect. In addition, sphingosine-1-phosphate accelerated the angiogenic process compared to vehicle-treated controls. Furthermore, sphingosine-1-phosphate treatment was associated with a significant proliferation of ovarian stromal cell as well as reduced necrosis and tissue hypoxia compared to the vehicle-treated controls. This resulted in a significantly lower percentage of apoptotic follicles in sphingosine-1-phosphate-treated transplants. We conclude that while sphingosine-1-phosphate promotes neoangiogenesis in ovarian transplants and reduces ischemic reperfusion injury, sphingosine-1-phosphate receptor agonists appear to functionally antagonize this process. Sphingosine-1-phosphate holds great promise to clinically enhance the survival and longevity of human autologous ovarian transplants.
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Affiliation(s)
- Reza Soleimani
- Laboratory of Molecular Reproduction, Institute for Fertility Preservation, Departments of Obstetrics and Gynecology and Cell Biology and Anatomy, New York Medical College, Valhalla, New York, United States of America
| | - Elke Heytens
- Laboratory of Molecular Reproduction, Institute for Fertility Preservation, Departments of Obstetrics and Gynecology and Cell Biology and Anatomy, New York Medical College, Valhalla, New York, United States of America
| | - Kutluk Oktay
- Laboratory of Molecular Reproduction, Institute for Fertility Preservation, Departments of Obstetrics and Gynecology and Cell Biology and Anatomy, New York Medical College, Valhalla, New York, United States of America
- * E-mail:
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70
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Lysophosphatidic acid suppresses endothelial cell CD36 expression and promotes angiogenesis via a PKD-1-dependent signaling pathway. Blood 2011; 117:6036-45. [PMID: 21441463 DOI: 10.1182/blood-2010-12-326017] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
In pathologic settings including retinal ischemia and malignant tumors, robust angiogenesis occurs despite the presence in the microenvironment of antiangiogenic proteins containing thrombospondin structural homology (TSR) domains. We hypothesized that antiangiogenesis mediated by TSR-containing proteins could be blunted by localized down-regulation of their cognate receptor on microvascular endothelial cells (MVECs), CD36. Through screening a panel of endothelial cell agonists, we found that lysophosphatidic acid (LPA) dramatically down-regulated CD36 surface expression on primary MVECs. LPA is a lipid-signaling mediator known to have proangiogenic activity, but the mechanisms are largely unknown. We observed that LPA caused CD36 down-regulation in a dose- and time-dependent manner and was long lasting. Down-regulation occurred at the transcriptional level via a signaling pathway involving specific LPA receptors and protein kinase D. LPA-induced MVEC CD36 repression significantly attenuated in vitro antiangiogenic responses to thrombospondin-1, including blockade of migration, tube formation, and VEGFR-2 signaling in response to fibroblast growth factor-2. In vivo relevance was demonstrated by showing that LPA abrogated thrombospondin-1-mediated inhibition of neovascularization of Matrigel plugs implanted in mice. Our data thus indicate that the proangiogenic mechanism of LPA may in part be via switching off the antiangiogenic switch mediated by TSR proteins and CD36.
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71
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Berdichevets IN, Tyazhelova TV, Shimshilashvili KR, Rogaev EI. Lysophosphatidic acid is a lipid mediator with wide range of biological activities. Biosynthetic pathways and mechanism of action. BIOCHEMISTRY (MOSCOW) 2011; 75:1088-97. [PMID: 21077828 DOI: 10.1134/s0006297910090026] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Lysophosphatidic acid (LPA) is a lipid mediator required for maintaining homeostasis of numerous physiological functions and also involved in development of some pathological processes through interactions with G protein-coupled receptors. Recently many data have appeared about the role of this phospholipid in humans, but pathways of LPA biosynthesis and mechanisms of its action remain unclear. This review presents modern concepts about biosynthesis, reception, and biological activity of LPA in humans. Natural and synthetic LPA analogs are considered in the view of their possible use in pharmacology as agonists and/or antagonists of G protein-coupled receptors of LPA.
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Affiliation(s)
- I N Berdichevets
- Vavilov Institute of General Genetics, Russian Academy of Sciences, Moscow, 119991, Russia.
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72
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Sefcik LS, Petrie Aronin CE, Awojoodu AO, Shin SJ, Mac Gabhann F, MacDonald TL, Wamhoff BR, Lynch KR, Peirce SM, Botchwey EA. Selective activation of sphingosine 1-phosphate receptors 1 and 3 promotes local microvascular network growth. Tissue Eng Part A 2011; 17:617-29. [PMID: 20874260 PMCID: PMC3043977 DOI: 10.1089/ten.tea.2010.0404] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2010] [Accepted: 09/27/2010] [Indexed: 01/12/2023] Open
Abstract
Proper spatial and temporal regulation of microvascular remodeling is critical to the formation of functional vascular networks, spanning the various arterial, venous, capillary, and collateral vessel systems. Recently, our group has demonstrated that sustained release of sphingosine 1-phosphate (S1P) from biodegradable polymers promotes microvascular network growth and arteriolar expansion. In this study, we employed S1P receptor-specific compounds to activate and antagonize different combinations of S1P receptors to elucidate those receptors most critical for promotion of pharmacologically induced microvascular network growth. We show that S1P(1) and S1P(3) receptors act synergistically to enhance functional network formation via increased functional length density, arteriolar diameter expansion, and increased vascular branching in the dorsal skinfold window chamber model. FTY720, a potent activator of S1P(1) and S1P(3), promoted a 107% and 153% increase in length density 3 and 7 days after implantation, respectively. It also increased arteriolar diameters by 60% and 85% 3 and 7 days after implantation. FTY720-stimulated branching in venules significantly more than unloaded poly(D, L-lactic-co-glycolic acid). When implanted on the mouse spinotrapezius muscle, FTY720 stimulated an arteriogenic response characterized by increased tortuosity and collateralization of branching microvascular networks. Our results demonstrate the effectiveness of S1P(1) and S1P(3) receptor-selective agonists (such as FTY720) in promoting microvascular growth for tissue engineering applications.
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Affiliation(s)
- Lauren S. Sefcik
- Department of Chemical and Biomolecular Engineering, Lafayette College, Easton, Pennsylvania
| | - Caren E. Petrie Aronin
- National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland
| | - Anthony O. Awojoodu
- Department of Biomedical Engineering, University of Virginia, Charlottesville, Virginia
| | - Soo J. Shin
- Department of Biomedical Engineering, University of Virginia, Charlottesville, Virginia
| | - Feilim Mac Gabhann
- Institute for Computational Medicine and Department of Biomedical Engineering, Johns Hopkins University, Baltimore, Maryland
| | | | - Brian R. Wamhoff
- Department of Cardiovascular Medicine, University of Virginia, Charlottesville, Virginia
- The Robert M. Berne Cardiovascular Research Center, Charlottesville, Virginia
| | - Kevin R. Lynch
- Department of Pharmacology, University of Virginia, Charlottesville, Virginia
| | - Shayn M. Peirce
- Department of Biomedical Engineering, University of Virginia, Charlottesville, Virginia
| | - Edward A. Botchwey
- Department of Biomedical Engineering, University of Virginia, Charlottesville, Virginia
- Department of Orthopaedic Surgery, University of Virginia, Charlottesville, Virginia
- Center for Immunity, Inflammation and Regenerative Medicine, University of Virginia, Charlottesville, Virginia
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73
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Goyal P, Behring A, Kumar A, Siess W. STK35L1 associates with nuclear actin and regulates cell cycle and migration of endothelial cells. PLoS One 2011; 6:e16249. [PMID: 21283756 PMCID: PMC3024402 DOI: 10.1371/journal.pone.0016249] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2010] [Accepted: 12/08/2010] [Indexed: 11/18/2022] Open
Abstract
BACKGROUND Migration and proliferation of vascular endothelial cells are essential for repair of injured endothelium and angiogenesis. Cyclins, cyclin-dependent kinases (CDKs), and cyclin-dependent kinase inhibitors play an important role in vascular tissue injury and wound healing. Previous studies suggest a link between the cell cycle and cell migration: cells present in the G(1) phase have the highest potential to migrate. The molecular mechanism linking these two processes is not understood. METHODOLOGY/PRINCIPAL FINDINGS In this study, we explored the function of STK35L1, a novel Ser/Thr kinase, localized in the nucleus and nucleolus of endothelial cells. Molecular biological analysis identified a bipartite nuclear localization signal, and nucleolar localization sequences in the N-terminal part of STK35L1. Nuclear actin was identified as a novel binding partner of STK35L1. A class III PDZ binding domains motif was identified in STK35L1 that mediated its interaction with actin. Depletion of STK35L1 by siRNA lead to an accelerated G(1) to S phase transition after serum-stimulation of endothelial cells indicating an inhibitory role of the kinase in G(1) to S phase progression. Cell cycle specific genes array analysis revealed that one gene was prominently downregulated (8.8 fold) in STK35L1 silenced cells: CDKN2A alpha transcript, which codes for p16(INK4a) leading to G(1) arrest by inhibition of CDK4/6. Moreover in endothelial cells seeded on Matrigel, STK35L1 expression was rapidly upregulated, and silencing of STK35L1 drastically inhibited endothelial sprouting that is required for angiogenesis. Furthermore, STK35L1 depletion profoundly impaired endothelial cell migration in two wound healing assays. CONCLUSION/SIGNIFICANCE The results indicate that by regulating CDKN2A and inhibiting G1- to S-phase transition STK35L1 may act as a central kinase linking the cell cycle and migration of endothelial cells. The interaction of STK35L1 with nuclear actin might be critical in the regulation of these fundamental endothelial functions.
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Affiliation(s)
- Pankaj Goyal
- Institut für Prophylaxe und Epidemiologie der Kreislaufkrankheiten, Klinikum Innenstadt, Universität München, Munich, Germany.
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74
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Lin CH, Lu J, Lee H. Interleukin-1β expression is required for lysophosphatidic Acid-induced lymphangiogenesis in human umbilical vein endothelial cells. Int J Inflam 2010; 2011:351010. [PMID: 21151531 PMCID: PMC2989649 DOI: 10.4061/2011/351010] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2010] [Revised: 05/24/2010] [Accepted: 06/28/2010] [Indexed: 11/20/2022] Open
Abstract
Lysophosphatidic acid (LPA) is a lipid mediator which binds to G-protein-coupled receptors and regulates various cellular responses, including inflammation of endothelial cells. Interleukin- (IL-) 1β, a proinflammatory cytokine, is elevated upon LPA treatment in human umbilical vein endothelial cells (HUVECs). Previous studies indicated that LPA upregulates vascular endothelial growth factor- (VEGF-) C and lymphatic marker expressions in HUVECs. However, the relationships between LPA-induced VEGF-C and IL-1β expressions are not clear. In this paper, we demonstrated that, in the presence of AF12198, an inhibitor of the IL-1 receptor abolished LPA-induced VEGF-C and lymphatic marker expressions in HUVECs. Furthermore, LPA-induced in vitro tube formation of HUVECs was also suppressed by pretreatment with AF12198. Our results suggest that LPA-stimulated lymphangiogenesis in HUVECs is mediated through IL-1β-induced VEGF-C expression.
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Affiliation(s)
- Chih-Hsin Lin
- Institute of Zoology, National Taiwan University, 1 Roosevelt Road, Section 4, Taipei 106, Taiwan
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75
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Son HJ, Lim YC, Ha KS, Kang SS, Cheong IY, Lee SJ, Park SW, Hwang BM. Propofol and aminophylline antagonize each other during the mobilization of intracellular calcium in human umbilical vein endothelial cells. J Korean Med Sci 2010; 25:1222-7. [PMID: 20676337 PMCID: PMC2908795 DOI: 10.3346/jkms.2010.25.8.1222] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/12/2009] [Accepted: 02/09/2010] [Indexed: 11/20/2022] Open
Abstract
This study examined whether propofol and aminophylline affect the mobilization of intracellular calcium in human umbilical vein endothelial cells. Intracellular calcium was measured using laser scanning confocal microscopy. Cultured and serum-starved cells on round coverslips were incubated with propofol or aminophylline for 30 min, and then stimulated with lysophosphatidic acid, propofol and aminophylline. The results were expressed as relative fluorescence intensity and fold stimulation. Propofol decreased the concentration of intracellular calcium, whereas aminophylline caused increased mobilization of intracellular calcium in a concentration-dependent manner. Propofol suppressed the lysophosphatidic acid-induced mobilization of intracellular calcium in a concentration-dependent manner. Propofol further prevented the aminophylline-induced increase of intracellular calcium at clinically relevant concentrations. However, aminophylline reversed the inhibitory effect of propofol on the elevation of intracellular calcium by lysophosphatidic acid. Our results suggest that propofol and aminophylline antagonize each other on the mobilization of intracellular calcium in human umbilical vein endothelial cells at clinically relevant concentrations. Serious consideration should be given to how this interaction affects mobilization of intracellular calcium when these two drugs are used together.
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Affiliation(s)
- Hee-Jeong Son
- Department of Anesthesiology and Pain Medicine, Kangwon National University Medical School, Chuncheon, Korea
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76
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Choi JW, Herr DR, Noguchi K, Yung YC, Lee CW, Mutoh T, Lin ME, Teo ST, Park KE, Mosley AN, Chun J. LPA receptors: subtypes and biological actions. Annu Rev Pharmacol Toxicol 2010; 50:157-86. [PMID: 20055701 DOI: 10.1146/annurev.pharmtox.010909.105753] [Citation(s) in RCA: 664] [Impact Index Per Article: 44.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Lysophosphatidic acid (LPA) is a small, ubiquitous phospholipid that acts as an extracellular signaling molecule by binding to and activating at least five known G protein-coupled receptors (GPCRs): LPA(1)-LPA(5). They are encoded by distinct genes named LPAR1-LPAR5 in humans and Lpar1-Lpar5 in mice. The biological roles of LPA are diverse and include developmental, physiological, and pathophysiological effects. This diversity is mediated by broad and overlapping expression patterns and multiple downstream signaling pathways activated by cognate LPA receptors. Studies using cloned receptors and genetic knockout mice have been instrumental in uncovering the significance of this signaling system, notably involving basic cellular processes as well as multiple organ systems such as the nervous system. This has further provided valuable proof-of-concept data to support LPA receptors and LPA metabolic enzymes as targets for the treatment of medically important diseases that include neuropsychiatric disorders, neuropathic pain, infertility, cardiovascular disease, inflammation, fibrosis, and cancer.
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Affiliation(s)
- Ji Woong Choi
- Department of Molecular Biology, Helen L. Dorris Institute for Neurological and Psychiatric Disorders, The Scripps Research Institute, La Jolla, California 92037, USA
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77
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Ptaszynska MM, Pendrak ML, Stracke ML, Roberts DD. Autotaxin signaling via lysophosphatidic acid receptors contributes to vascular endothelial growth factor-induced endothelial cell migration. Mol Cancer Res 2010; 8:309-21. [PMID: 20197381 PMCID: PMC2841699 DOI: 10.1158/1541-7786.mcr-09-0288] [Citation(s) in RCA: 54] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
Important roles for vascular endothelial growth factor (VEGF) and autotaxin (ATX) have been established for embryonic vasculogenesis and cancer progression. We examined whether these two angiogenic factors cooperate in regulation of endothelial cell migratory responses. VEGF stimulated expression of ATX and LPA1, a receptor for the ATX enzymatic product lysophosphatidic acid (LPA), in human umbilical vein endothelial cells. Knockdown of ATX expression significantly decreased mRNA levels for the receptors LPA1, LPA2, S1P1, S1P2, S1P3, and VEGFR2 and abolished cell migration to lysophosphatidylcholine, LPA, recombinant ATX, and VEGF. Migration to sphingosylphosphorylcholine and sphinogosine-1-phosphate was also reduced in ATX knockdown cells, whereas migration to serum remained unchanged. Furthermore, ATX knockdown decreased Akt2 mRNA levels, whereas LPA treatment strongly stimulated Akt2 expression. We propose that VEGF stimulates LPA production by inducing ATX expression. VEGF also increases LPA1 signaling, which in turn increases Akt2 expression. Akt2 is strongly associated with cancer progression, cellular migration, and promotion of epithelial-mesenchymal transition. These data show a role for ATX in maintaining expression of receptors required for VEGF and lysophospholipids to accelerate angiogenesis. Because VEGF and ATX are upregulated in many cancers, the regulatory mechanism proposed in these studies could apply to cancer-related angiogenesis and cancer progression. These data further suggest that ATX could be a prognostic factor or a target for therapeutic intervention in several cancers.
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MESH Headings
- Cell Movement/drug effects
- Cell Movement/physiology
- Cells, Cultured
- Endothelial Cells/cytology
- Endothelial Cells/drug effects
- Endothelial Cells/metabolism
- Humans
- Multienzyme Complexes/drug effects
- Multienzyme Complexes/genetics
- Multienzyme Complexes/metabolism
- Neovascularization, Pathologic/genetics
- Neovascularization, Pathologic/metabolism
- Neovascularization, Pathologic/physiopathology
- Phosphodiesterase I/drug effects
- Phosphodiesterase I/genetics
- Phosphodiesterase I/metabolism
- Phosphoric Diester Hydrolases
- Proto-Oncogene Proteins c-akt/drug effects
- Proto-Oncogene Proteins c-akt/metabolism
- Pyrophosphatases/drug effects
- Pyrophosphatases/genetics
- Pyrophosphatases/metabolism
- RNA Interference/physiology
- RNA, Messenger/drug effects
- RNA, Messenger/metabolism
- Receptors, Lysophosphatidic Acid/drug effects
- Receptors, Lysophosphatidic Acid/metabolism
- Receptors, Lysosphingolipid/drug effects
- Receptors, Lysosphingolipid/metabolism
- Receptors, Vascular Endothelial Growth Factor/drug effects
- Receptors, Vascular Endothelial Growth Factor/metabolism
- Signal Transduction/drug effects
- Signal Transduction/physiology
- Up-Regulation/drug effects
- Up-Regulation/physiology
- Vascular Endothelial Growth Factor A/metabolism
- Vascular Endothelial Growth Factor A/pharmacology
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Affiliation(s)
- Malgorzata M Ptaszynska
- Laboratory of Pathology, Center for Cancer Research, National Cancer Institute, Bethesda, MD 20892-1500, USA
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Cheng R, Cheng L, Shao MY, Yang H, Wang FM, Hu T, Zhou XD. Roles of lysophosphatidic acid and the Rho-associated kinase pathway in the migration of dental pulp cells. Exp Cell Res 2010; 316:1019-27. [PMID: 20064505 DOI: 10.1016/j.yexcr.2010.01.002] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2009] [Revised: 12/15/2009] [Accepted: 01/04/2010] [Indexed: 01/13/2023]
Abstract
During the dental pulp repair process, dental pulp cells (DPCs) migrate to the site of injury and differentiate into odontoblasts or odontoblast-like cells. Although migration of DPCs is an important reparative process, the underlying mechanism remains unknown. The objective of this study was to determine the roles of lysophosphatidic acid (LPA) and the Rho-associated kinase (ROCK) pathway in the migration and morphology of dental pulp cells and alpha smooth muscle actin expression in vitro. We demonstrated that both LPA and ROCK inhibition enhanced cell motility and that their combined effects significantly increased migration rate. LPA induced fine cytoskeleton assembly and increased the level of alpha smooth muscle actin (alpha-SMA). ROCK inhibition by Y-27632 and ROCK-(1+2) small interfering RNA (siRNA) resulted in less actin cytoskeleton formation, a lower alpha-SMA level, a star-like cellular morphology and membrane ruffling. LPA and ROCK inhibition induced activation of another Rho GTPase, Rac, which may explain how LPA and ROCK inhibition increases cellmigration and lamellipodium formation.
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Affiliation(s)
- Ran Cheng
- The State Key Laboratory of Oral Diseases, Sichuan University, 14# 3rd section, Renmin South Road, Chengdu 610041, PR China.
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79
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Lysophospholipids enhance taurine release from rat retinal vascular endothelial cells under hypoosmotic stress. Microvasc Res 2009; 78:332-7. [DOI: 10.1016/j.mvr.2009.09.005] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2009] [Revised: 09/16/2009] [Accepted: 09/28/2009] [Indexed: 11/18/2022]
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Teo ST, Yung YC, Herr DR, Chun J. Lysophosphatidic acid in vascular development and disease. IUBMB Life 2009; 61:791-9. [PMID: 19621353 DOI: 10.1002/iub.220] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Lysophosphatidic acid (LPA) is a small signaling lipid that is capable of stimulating a plethora of different cellular responses through the activation of its family of cognate G protein-coupled receptors. LPA mediates a wide range of biological effects in many tissue types that have been recently reviewed; however, its effects on vasculature development and function have received comparatively less examination. In this review, literature on the actions of LPA in three main aspects of vascular development (vasculogenesis, angiogenesis, and vascular maturation) is discussed. In addition, evidence for the roles of LPA signaling in the formation of secondary vascular structures, such as the blood brain barrier, is considered, consistent with significant roles for LPA signaling in vascular development, function, and disease.
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Affiliation(s)
- Siew T Teo
- Department of Molecular Biology, Helen L. Dorris Child and Adolescent Neuropsychiatric Disorder Institute, The Scripps Research Institute, ICND-118, La Jolla, CA 92037, USA
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81
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Syuto T, Abe M, Yokoyama Y, Ishikawa O. Mammalian Diaphanous (mDia) may be involved in the signal transduction of sphingosine-1-phosphate on developing actin stress fiber of human fibroblasts. Wound Repair Regen 2009; 17:589-97. [PMID: 19614924 DOI: 10.1111/j.1524-475x.2009.00510.x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Sphingosine 1-phosphate (S1P) is a biologically active lipid mediator with many pivotal roles in the regulation of cell growth, migration, differentiation, and apoptosis. However, signal transduction mediated by S1P in human fibroblasts is still unclear. We investigated signal transduction by S1P in human fibroblasts using collagen matrix contraction in order to explore whether or not S1P could be applied for the treatment of skin wound healing. We found that S1P promoted floating collagen matrices' contraction, for the in vitro model of initial phase wound contraction, in which some kinds of G protein, such as Gialpha, Rac 1, and Rho, were involved. However, Rho-associated coiled-coil forming kinase (ROCK) was partially involved in S1P-promoting floating collagen matrices contraction. Mammalian Diaphanous (mDia) as well as ROCK have been identified to be putative downstream target molecules of Rho. In mDia-silenced cells, the ROCK inhibitor suppressed actin stress fiber formation regardless of the presence or absence of S1P. Our results indicate that mDia as well as ROCK may be situated downstream of Gialpha, Rac1, and Rho to induce actin stress fiber development by human fibroblasts stimulated with SIP.
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Affiliation(s)
- Tomoko Syuto
- Department of Dermatology, Gunma University Graduate School of Medicine, Maebashi, Japan.
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82
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Chen F, Qian Y, Duan Y, Ren W, Yang Y, Zhang C, Qiu Y, Ji Y. Down-regulation of 67LR reduces the migratory activity of human glioma cells in vitro. Brain Res Bull 2009; 79:402-8. [DOI: 10.1016/j.brainresbull.2009.04.019] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2009] [Revised: 04/13/2009] [Accepted: 04/13/2009] [Indexed: 10/20/2022]
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83
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Rosen H, Gonzalez-Cabrera PJ, Sanna MG, Brown S. Sphingosine 1-phosphate receptor signaling. Annu Rev Biochem 2009; 78:743-68. [PMID: 19231986 DOI: 10.1146/annurev.biochem.78.072407.103733] [Citation(s) in RCA: 328] [Impact Index Per Article: 20.5] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
The sphingosine 1-phosphate (S1P) receptor signaling system is a productive model system. A hydrophobic zwitterionic lysophospholipid ligand with difficult physical properties interacts with five high-affinity G protein-coupled receptors to generate multiple downstream signals. These signals modulate homeostasis and pathology on a steep agonist concentration-response curve. Ligand presence is essential for vascular development and endothelial integrity, while acute increases in ligand concentrations result in cardiac death. Understanding this integrated biochemical system has exemplified the impact of both genetics and chemistry. Developing specific tools with defined biochemical properties for the reversible modulation of signals in real time has been essential to complement insights gained from genetic approaches that may be irreversible and compensated. Despite its knife-edge between life and death, this system, based in part on receptor subtype-selectivity and in part on differential attenuation of deleterious signals, now appears to be on the cusp of meaningful therapy for multiple sclerosis.
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Affiliation(s)
- Hugh Rosen
- Departments of Chemical Physiology and Immunology and The Scripps Research Institute Molecular Screening Center, The Scripps Research Institute, La Jolla, CA 92037, USA.
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84
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Chang CL, Ho MC, Lee PH, Hsu CY, Huang WP, Lee H. S1P(5) is required for sphingosine 1-phosphate-induced autophagy in human prostate cancer PC-3 cells. Am J Physiol Cell Physiol 2009; 297:C451-8. [PMID: 19474291 DOI: 10.1152/ajpcell.00586.2008] [Citation(s) in RCA: 62] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Sphingosine 1-phosphate (S1P) is a platelet- and endothelial cell-released lysophospholipid that regulates various cellular functions through activating a specific family of G protein-coupled receptors. Both platelet activation and angiogenesis play important roles in cancer development, implying that cancer cells might encounter a large amount of S1P during these processes. Cancer cells, in the meantime, may experience nutrient deprivation and rely on autophagy for early development. Whether extracellular S1P regulates autophagy remains to be tested. In the present work, we investigated whether autophagy is regulated by S1P in PC-3 cells. Through monitoring the modification patterns of LC3 by Western blotting, we demonstrated that autophagy was induced by exogenously applied S1P in PC-3 cells. This observation was further confirmed by fluorescence microscopy using PC-3 cells stably expressing enhanced green fluorescent protein-LC3. By applying small interfering RNA and dihydro-S1P, S1P(5) activation was found to be involved in this process. Besides, mammalian target of rapamycin signaling was inhibited upon S1P treatment. Taken together, our results suggest that, under serum-starved conditions, S1P further upregulates autophagic activity through S1P(5)-dependent pathways in PC-3 cells.
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Affiliation(s)
- Chi-Lun Chang
- Institute of Zoology, National Taiwan University, Taipei, Taiwan, ROC
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85
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Michaud MD, Robitaille GA, Gratton JP, Richard DE. Sphingosine-1-phosphate: a novel nonhypoxic activator of hypoxia-inducible factor-1 in vascular cells. Arterioscler Thromb Vasc Biol 2009; 29:902-8. [PMID: 19423865 DOI: 10.1161/atvbaha.109.185280] [Citation(s) in RCA: 50] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
OBJECTIVE Sphingosine-1-phosphate (S1P) is a potent bioactive phospholipid responsible for a variety of vascular cell responses. Hypoxia-inducible factor-1 (HIF-1) is a transcriptional activator of genes essential for adaptation to low oxygen. S1P and HIF-1 are both important mediators of vascular cell responses such as migation, proliferation, and survival. Studies have shown that nonhypoxic stimuli can activate HIF-1 in oxygenated conditions. Here, we attempt to determine whether S1P can modulate the vascular activation of HIF-1. METHODS AND RESULTS We show that in vascular endothelial and smooth muscle cells, activation of the S1P type-2 receptor by S1P strongly increases HIF-1 alpha protein levels, the active subunit of HIF-1. This is achieved through pVHL-independent stabilization of HIF-1 alpha. We demonstrate that the HIF-1 nuclear complex, formed on S1P stimulation, is transcriptionally active and specifically binds to a hypoxia-responsive elements. Moreover, S1P activates the expression of genes known to be closely regulated by HIF-1. CONCLUSIONS Our results identify S1P as a novel and potent nonhypoxic activator of HIF-1. We believe that understanding the role played by HIF-1 in S1P gene regulation will have a strong impact on different aspects of vascular biology.
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Affiliation(s)
- Maude D Michaud
- Centre de Recherche du CHUQ, L'Hôtel-Dieu de Québec, Québec, Canada
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86
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Dunworth WP, Caron KM. G protein-coupled receptors as potential drug targets for lymphangiogenesis and lymphatic vascular diseases. Arterioscler Thromb Vasc Biol 2009; 29:650-6. [PMID: 19265032 PMCID: PMC2761011 DOI: 10.1161/atvbaha.109.185066] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
G protein-coupled receptors (GPCRs) are widely expressed cell surface receptors that have been successfully exploited for the treatment of a variety of human diseases. Recent studies in genetically engineered mouse models have led to the identification of several GPCRs important for lymphatic vascular development and function. The adrenomedullin receptor, which consists of an oligomer between calcitonin receptor-like receptor and receptor activity modifying protein 2, is required for normal lymphatic vascular development and regulates lymphatic capillary permeability in mice. Numerous studies also suggest that lysophospholipid receptors are involved in the development of lymphatic vessels and lymphatic endothelial cell permeability. Given our current lack of pharmacological targets for the treatment of lymphatic vascular diseases like lymphedema, the continued identification and study of GPCRs in lymphatic endothelial cells may eventually lead to major breakthroughs and new pharmacological strategies for the treatment of lymphedema.
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Affiliation(s)
- William P Dunworth
- Department of Cell and Molecular Physiology, The University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
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87
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Yanagida K, Masago K, Nakanishi H, Kihara Y, Hamano F, Tajima Y, Taguchi R, Shimizu T, Ishii S. Identification and characterization of a novel lysophosphatidic acid receptor, p2y5/LPA6. J Biol Chem 2009; 284:17731-41. [PMID: 19386608 DOI: 10.1074/jbc.m808506200] [Citation(s) in RCA: 200] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
p2y5 is an orphan G protein-coupled receptor that is closely related to the fourth lysophosphatidic acid (LPA) receptor, LPA4. Here we report that p2y5 is a novel LPA receptor coupling to the G13-Rho signaling pathway. "LPA receptor-null" RH7777 and B103 cells exogenously expressing p2y5 showed [3H]LPA binding, LPA-induced [35S]guanosine 5'-3-O-(thio)triphosphate binding, Rho-dependent alternation of cellular morphology, and Gs/13 chimeric protein-mediated cAMP accumulation. LPA-induced contraction of human umbilical vein endothelial cells was suppressed by small interfering RNA knockdown of endogenously expressed p2y5. We also found that 2-acyl-LPA had higher activity to p2y5 than 1-acyl-LPA. A recent study has suggested that p2y5 is an LPA receptor essential for human hair growth. We confirmed that p2y5 is a functional LPA receptor and propose to designate this receptor LPA6.
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Affiliation(s)
- Keisuke Yanagida
- Department of Biochemistry and Molecular Biology, Faculty of Medicine, Univerfsity of Tokyo, Tokyo, Japan
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88
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Abstract
Sphingosine-1-phosphate (S1P) is a phosphorylated product of sphingosine, the core structure of the class of lipids termed sphingolipids. S1P is a naturally occurring lipid metabolite, and usually is present at a concentration of a few 100 nanomolar in human sera. S1P has been found to exert a diverse set of physiological and pathophysiological responses in mammalian tissues through the activation of heterotrimeric G-proteins that in turn modulate the activity of various downstream effecter molecules. In blood vessels, vascular endothelial cells and smooth muscle cells express specific receptors for S1P that modulate vascular tone. This article will provide a brief overview of S1P metabolism in the vasculature and will discuss some of the pathways whereby S1P regulates intracellular signal transduction pathways in endothelial and smooth muscle cells, leading to the activation of both vasorelaxation and vasoconstriction responses.
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Affiliation(s)
- Junsuke Igarashi
- Department of Cardiovascular Physiology, Kagawa University, 1750-1 Ikenobe, Miki-cho, Kita-gun, Kagawa 761-0793, Japan.
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89
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Alford SK, Kaneda MM, Wacker BK, Elbert DL. Endothelial cell migration in human plasma is enhanced by a narrow range of added sphingosine 1-phosphate: implications for biomaterials design. J Biomed Mater Res A 2009; 88:205-12. [PMID: 18286622 DOI: 10.1002/jbm.a.31885] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Abstract
Sphingosine 1-phosphate (S1P) promotes endothelial cell migration in vitro and may potentially impact the endothelialization of implanted biomaterials. However, the effects of S1P on endothelial cells (EC) in flowing blood could be negligible due to preactivation of signaling cascades. We previously developed biomaterials that release S1P and wished to determine through in vitro experiments the extent to which EC respond to S1P added to human platelet poor plasma. We found that addition of 200 nM S1P to platelet poor plasma significantly increased cell migration in two migration models. A lower concentration of S1P added to plasma (100 nM) did not increase endothelial cell migration rates, while the cell migration response was saturated above 200 nM S1P. Expression of the main S1P receptor in EC, S1P(1), was elevated in plasma compared to low serum medium, but addition of VEGF or fluid flow elicited a further increase in S1P(1) mRNA, consistent with the synergistic effects observed between S1P, VEGF, and fluid flow. Thus, sustained delivery of S1P from biomaterials might only enhance endothelial cell migration if the concentration of S1P at the surface of the material stimulated adjacent EC to the same extent as approximately 200 nM S1P added to plasma.
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Affiliation(s)
- Shannon K Alford
- Department of Biomedical Engineering and Center for Materials Innovation, Washington University in St. Louis, St. Louis, Missouri, USA
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90
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Haddoub R, Rützler M, Robin A, Flitsch SL. Design, synthesis and assaying of potential aquaporin inhibitors. Handb Exp Pharmacol 2009:385-402. [PMID: 19096788 DOI: 10.1007/978-3-540-79885-9_19] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
The aquaporin protein family performs fundamental tasks in the physiology of several organs in the human body. Their roles in several disorders known to involve water movement make them attractive targets for the development of novel drug therapies.This chapter describes assays commonly used to study the water permeability across AQPs. It also describes the effect of some known inhibitors of aquaporins on water permeability, such as mercury, gold, silver, copper, phloretin, tetraethyl ammonium salts and acetazolamide compounds.
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Affiliation(s)
- Rose Haddoub
- Manchester Interdisciplinary Biocentre (MIB) & The School of Chemistry, University of Manchester, 131 Princess Street, Manchester, M1 7DN, UK
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91
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Inoue M, Ma L, Aoki J, Ueda H. Simultaneous stimulation of spinal NK1 and NMDA receptors produces LPC which undergoes ATX-mediated conversion to LPA, an initiator of neuropathic pain. J Neurochem 2008; 107:1556-65. [DOI: 10.1111/j.1471-4159.2008.05725.x] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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92
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Lee PF, Yeh AT, Bayless KJ. Nonlinear optical microscopy reveals invading endothelial cells anisotropically alter three-dimensional collagen matrices. Exp Cell Res 2008; 315:396-410. [PMID: 19041305 DOI: 10.1016/j.yexcr.2008.10.040] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2008] [Revised: 10/19/2008] [Accepted: 10/23/2008] [Indexed: 12/21/2022]
Abstract
The interactions between endothelial cells (ECs) and the extracellular matrix (ECM) are fundamental in mediating various steps of angiogenesis, including cell adhesion, migration and sprout formation. Here, we used a noninvasive and non-destructive nonlinear optical microscopy (NLOM) technique to optically image endothelial sprouting morphogenesis in three-dimensional (3D) collagen matrices. We simultaneously captured signals from collagen fibers and endothelial cells using second harmonic generation (SHG) and two-photon excited fluorescence (TPF), respectively. Dynamic 3D imaging revealed EC interactions with collagen fibers along with quantifiable alterations in collagen matrix density elicited by EC movement through and morphogenesis within the matrix. Specifically, we observed increased collagen density in the area between bifurcation points of sprouting structures and anisotropic increases in collagen density around the perimeter of lumenal structures, but not advancing sprout tips. Proteinase inhibition studies revealed membrane-associated matrix metalloproteinase were utilized for sprout advancement and lumen expansion. Rho-associated kinase (p160ROCK) inhibition demonstrated that the generation of cell tension increased collagen matrix alterations. This study followed sprouting ECs within a 3D matrix and revealed that the advancing structures recognize and significantly alter their extracellular environment at the periphery of lumens as they progress.
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Affiliation(s)
- Po-Feng Lee
- Department of Biomedical Engineering, Texas A&M University, College Station, TX 77843, USA
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93
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Shimizu H, Toyama O, Shiota M, Kim-Mitsuyama S, Miyazaki H. Protein Tyrosine Phosphatase LMW-PTP Exhibits Distinct Roles Between Vascular Endothelial and Smooth Muscle Cells. J Recept Signal Transduct Res 2008; 25:19-33. [PMID: 15960392 DOI: 10.1081/rrs-200047876] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
The present study examined the cellular functions of low-molecular-weight protein tyrosine phosphatase (LMW-PTP), which consists of two active isoforms IF-1 and IF-2, in vascular smooth muscle cells (VSMCs) and endothelial cells (ECs), focusing on cell growth and migration. We transduced recombinant IF-1 and IF-2, and ribozyme targeting both isoforms using an adenovirus vector in these cells. We detected the expression of IF-1 and IF-2 in both types of cells. IF-1 as well as IF-2 inhibited PDGF-induced DNA synthesis and migration in VSMCs. In contrast, both isoforms enhanced lysophosphatidic acid-stimulated cell migration without change in DNA synthesis in ECs. Whereas there is a report indicating that reactive oxygen species-dependent inactivation of LMW-PTP regulates actin cytoskeleton reorganization during cell spreading and migration, the isoforms conversely suppressed the PDGF-induced H2O2 generation with subsequent decrease in the p38 activity in VSMCs. Catalytically inactive LMW-PTP exerted the opposite and similar effects to the wild type in ECs and in VSMCs, respectively, suggesting that substrates for the phosphatase differ between these cells. Moreover, high concentrations of glucose suppressed the expression of LMW-PTP in both cells. These data suggest that LMW-PTP negatively regulates the pathogenesis of atherosclerosis and that glucose-dependent suppression of LMW-PTP expression may promote the development of atherosclerosis in diabetics.
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MESH Headings
- Animals
- Arteriosclerosis/enzymology
- Arteriosclerosis/etiology
- Cells, Cultured
- DNA/biosynthesis
- DNA, Complementary/genetics
- Endothelium, Vascular/cytology
- Endothelium, Vascular/drug effects
- Endothelium, Vascular/enzymology
- Gene Expression/drug effects
- Glucose/pharmacology
- Isoenzymes/chemistry
- Isoenzymes/genetics
- Isoenzymes/metabolism
- Molecular Weight
- Muscle, Smooth, Vascular/cytology
- Muscle, Smooth, Vascular/drug effects
- Muscle, Smooth, Vascular/enzymology
- Platelet-Derived Growth Factor/pharmacology
- Protein Tyrosine Phosphatases/chemistry
- Protein Tyrosine Phosphatases/genetics
- Protein Tyrosine Phosphatases/metabolism
- Rats
- Signal Transduction/drug effects
- Swine
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Affiliation(s)
- Hidehisa Shimizu
- Gene Research Center, University of Tsukuba, Ibaraki 305-8572, Japan
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94
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Peest U, Sensken SC, Andréani P, Hänel P, Van Veldhoven PP, Gräler MH. S1P-lyase independent clearance of extracellular sphingosine 1-phosphate after dephosphorylation and cellular uptake. J Cell Biochem 2008; 104:756-72. [PMID: 18172856 DOI: 10.1002/jcb.21665] [Citation(s) in RCA: 56] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Sphingosine 1-phosphate (S1P) is the natural ligand for a specific family of G protein-coupled receptors (-Rs). The type 1 S1P-R (S1P(1)) is important for lymphocyte egress, and blood-borne S1P as the natural ligand for S1P(1) is involved in the maintenance of lymphocyte circulation. This report reveals that extracellular S1P was cleared by all tested primary cells and cell lines with exponential progression. Clearance of S1P, but not sphingosine (Sph) was inhibited with the protein phosphatase inhibitor sodium orthovanadate. Fluorescence microscopy and flow cytometry using fluorescently labeled S1P and Sph showed a major cellular uptake of Sph, but not S1P. HPLC-analyses with C17-Sph demonstrated that cellular Sph accumulation was transient in tested cell lines, but enduring in mouse splenocytes. Sub cellular fractionation resulted in dephosphorylation of S1P to Sph by nuclear, membrane, and cytosolic fractions. Degradation of Sph however only occurred in combined membrane and cytosolic fractions. Inhibitors for Sph kinases 1/2, ceramide synthase, and S1P-lyase, as well as S1P-lyase deficiency did not block clearance of extracellular S1P. In vivo experiments revealed a transient increase in plasma S1P levels after single intravenous injection into C57BL/6 mice. This exogenously added S1P was cleared within 15-30 min in contrast to ex vivo incubation of whole blood which required more than 8 h for comparable clearance from plasma. Our data thus show that extracellular S1P is dephosphorylated and subsequently converted by cells, which appears to be important for clearance of the signaling molecule S1P in the local tissue environment after infections or injuries.
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Affiliation(s)
- Ulrike Peest
- Institute for Immunology, Hannover Medical School, Carl-Neuberg-Str. 1, 30625 Hanover, Germany
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95
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Bucki R, Byfield FJ, Kulakowska A, McCormick ME, Drozdowski W, Namiot Z, Hartung T, Janmey PA. Extracellular Gelsolin Binds Lipoteichoic Acid and Modulates Cellular Response to Proinflammatory Bacterial Wall Components. THE JOURNAL OF IMMUNOLOGY 2008; 181:4936-44. [DOI: 10.4049/jimmunol.181.7.4936] [Citation(s) in RCA: 64] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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96
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Freitas VM, Rangel M, Bisson LF, Jaeger RG, Machado-Santelli GM. The geodiamolide H, derived from Brazilian sponge Geodia corticostylifera, regulates actin cytoskeleton, migration and invasion of breast cancer cells cultured in three-dimensional environment. J Cell Physiol 2008; 216:583-94. [PMID: 18330887 DOI: 10.1002/jcp.21432] [Citation(s) in RCA: 54] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
We are investigating effects of the depsipeptide geodiamolide H, isolated from the Brazilian sponge Geodia corticostylifera, on cancer cell lines grown in 3D environment. As shown previously geodiamolide H disrupts actin cytoskeleton in both sea urchin eggs and breast cancer cell monolayers. We used a normal mammary epithelial cell line MCF 10A that in 3D assay results formation of polarized spheroids. We also used cell lines derived from breast tumors with different degrees of differentiation: MCF7 positive for estrogen receptor and the Hs578T, negative for hormone receptors. Cells were placed on top of Matrigel. Spheroids obtained from these cultures were treated with geodiamolide H. Control and treated samples were analyzed by light and confocal microscopy. Geodiamolide H dramatically affected the poorly differentiated and aggressive Hs578T cell line. The peptide reverted Hs578T malignant phenotype to polarized spheroid-like structures. MCF7 cells treated by geodiamolide H exhibited polarization compared to controls. Geodiamolide H induced striking phenotypic modifications in Hs578T cell line and disruption of actin cytoskeleton. We investigated effects of geodiamolide H on migration and invasion of Hs578T cells. Time-lapse microscopy showed that the peptide inhibited migration of these cells in a dose-dependent manner. Furthermore invasion assays revealed that geodiamolide H induced a 30% decrease on invasive behavior of Hs578T cells. Our results suggest that geodiamolide H inhibits migration and invasion of Hs578T cells probably through modifications in actin cytoskeleton. The fact that normal cell lines were not affected by treatment with geodiamolide H stimulates new studies towards therapeutic use for this peptide.
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Affiliation(s)
- Vanessa M Freitas
- Department of Cell and Developmental Biology, Institute of Biomedical Sciences, University of São Paulo, São Paulo, Brazil.
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97
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Caballero S, Swaney J, Moreno K, Afzal A, Kielczewski J, Stoller G, Cavalli A, Garland W, Hansen G, Sabbadini R, Grant MB. Anti-sphingosine-1-phosphate monoclonal antibodies inhibit angiogenesis and sub-retinal fibrosis in a murine model of laser-induced choroidal neovascularization. Exp Eye Res 2008; 88:367-77. [PMID: 18723015 DOI: 10.1016/j.exer.2008.07.012] [Citation(s) in RCA: 73] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2008] [Revised: 07/10/2008] [Accepted: 07/13/2008] [Indexed: 12/30/2022]
Abstract
The efficacy of novel monoclonal antibodies that neutralize the pro-angiogenic mediator, sphingosine-1-phosphate (S1P), were tested using in vitro and in vivo angiogenesis models, including choroidal neovascularization (CNV) induced by laser disruption of Bruch's membrane. S1P receptor levels in human brain choroid plexus endothelial cells (CPEC), human lung microvascular endothelial cells, human retinal vascular endothelial cells, and circulating endothelial progenitor cells were examined by semi-quantitative PCR. The ability of murine or humanized anti-S1P monoclonal antibodies (mAbs) to inhibit S1P-mediated microvessel tube formation by CPEC on Matrigel was evaluated and capillary density in subcutaneous growth factor-loaded Matrigel plugs was determined following anti-S1P treatment. S1P promoted in vitro capillary tube formation in CPEC consistent with the presence of cognate S1P(1-5) receptor expression by these cells and the S1P antibody induced a dose-dependent reduction in microvessel tube formation. In a murine model of laser-induced rupture of Bruch's membrane, S1P was detected in posterior cups of mice receiving laser injury, but not in uninjured controls. Intravitreous injection of anti-S1P mAbs dramatically inhibited CNV formation and sub-retinal collagen deposition in all treatment groups (p<0.05 compared to controls), thereby identifying S1P as a previously unrecognized mediator of angiogenesis and subretinal fibrosis in this model. These findings suggest that neutralizing S1P with anti-S1P mAbs may be a novel method of treating patients with exudative age-related macular degeneration by reducing angiogenesis and sub-retinal fibrosis, which are responsible for visual acuity loss in this disease.
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Affiliation(s)
- Sergio Caballero
- Department of Pharmacology & Therapeutics, University of Florida, Gainesville, FL, USA
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98
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Lee SJ, Chan TH, Chen TC, Liao BK, Hwang PP, Lee H. LPA1 is essential for lymphatic vessel development in zebrafish. FASEB J 2008; 22:3706-15. [PMID: 18606866 DOI: 10.1096/fj.08-106088] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Lysophosphatidic acid (LPA) has long been implicated in regulating vascular development via endothelial cell-expressed G protein-coupled receptors. However, because of a lack of notable vascular defects reported in LPA receptor knockout mouse studies, the regulation of vasculature by LPA receptors in vivo is still uncertain. Using zebrafish as a model, we studied the gene expression patterns and functions of an LPA receptor, LPA(1), during embryonic development, in particular, vascular formation. Whole-mount in situ hybridization experiments revealed that zebrafish lpa(1) (zlpa(1)) was ubiquitously expressed early in development, and its expression domains were later localized to the head region and the vicinity of the dorsal aorta. The expression of zlpa(1) surrounding the dorsal aorta suggests its role in vasculature development. Knocking down of zLPA(1) by injecting morpholino (MO) oligonucleotides at 0.625-1.25 ng per embryo resulted in the absence of thoracic duct and edema in pericardial sac and trunk in a dose-dependent manner. These zlpa(1)-MO-resulted defects could be specifically rescued by ectopic expression of zlpa(1). In addition, overexpression of vegf-c, a well-known lymphangiogenic factor, also partially ameliorated the inhibition of thoracic duct development. Taken together, these results demonstrate that LPA(1) is necessary for lymphatic vessel formation during embryonic development in zebrafish.
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Affiliation(s)
- Shyh-Jye Lee
- Institute of Zoology, National Taiwan University, Taipei, Taiwan 106, ROC.
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99
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Sefcik LS, Petrie Aronin CE, Wieghaus KA, Botchwey EA. Sustained release of sphingosine 1-phosphate for therapeutic arteriogenesis and bone tissue engineering. Biomaterials 2008; 29:2869-77. [PMID: 18405965 PMCID: PMC2711780 DOI: 10.1016/j.biomaterials.2008.03.017] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2008] [Accepted: 03/16/2008] [Indexed: 10/22/2022]
Abstract
Sphingosine 1-phosphate (S1P) is a bioactive phospholipid that impacts migration, proliferation, and survival in diverse cell types, including endothelial cells, smooth muscle cells, and osteoblast-like cells. In this study, we investigated the effects of sustained release of S1P on microvascular remodeling and associated bone defect healing in vivo. The murine dorsal skinfold window chamber model was used to evaluate the structural remodeling response of the microvasculature. Our results demonstrated that 1:400 (w/w) loading and subsequent sustained release of S1P from poly(lactic-co-glycolic acid) (PLAGA) significantly enhanced lumenal diameter expansion of arterioles and venules after 3 and 7 days. Incorporation of 5-bromo-2-deoxyuridine (BrdU) at day 7 revealed significant increases in mural cell proliferation in response to S1P delivery. Additionally, three-dimensional (3D) scaffolds loaded with S1P (1:400) were implanted into critical-size rat calvarial defects, and healing of bony defects was assessed by radiograph X-ray, microcomputed tomography (muCT), and histology. Sustained release of S1P significantly increased the formation of new bone after 2 and 6 weeks of healing and histological results suggest increased numbers of blood vessels in the defect site. Taken together, these experiments support the use of S1P delivery for promoting microvessel diameter expansion and improving the healing outcomes of tissue-engineered therapies.
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Affiliation(s)
- Lauren S. Sefcik
- Dept. of Biomedical Engineering, University of Virginia, Box 800759, Health System, Charlottesville, VA 22908
| | - Caren E. Petrie Aronin
- Dept. of Biomedical Engineering, University of Virginia, Box 800759, Health System, Charlottesville, VA 22908
| | - Kristen A. Wieghaus
- Dept. of Biomedical Engineering, University of Virginia, Box 800759, Health System, Charlottesville, VA 22908
| | - Edward A. Botchwey
- Dept. of Biomedical Engineering, University of Virginia, Box 800759, Health System, Charlottesville, VA 22908, Tel: 434-243-9846, Fax: 434-982-3870,
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100
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Chang CL, Hsu HY, Lin HY, Chiang W, Lee H. Lysophosphatidic acid-induced oxidized low-density lipoprotein uptake is class A scavenger receptor-dependent in macrophages. Prostaglandins Other Lipid Mediat 2008; 87:20-5. [PMID: 18585471 DOI: 10.1016/j.prostaglandins.2008.05.002] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2008] [Accepted: 05/30/2008] [Indexed: 02/07/2023]
Abstract
Lysophosphatidic acid (LPA) is a low-molecular-weight lysophospholipid enriched in platelets and mildly oxidized low-density lipoprotein (OxLDL). It is suggested that LPA is involved in atherosclerosis, and our previous studies showed that LPA regulates inflammation in multiple cell types. The main aim of this study was to investigate the effects of LPA on the uptake of OxLDL by mouse J774A.1 macrophages. We observed that LPA upregulated fluorescence-labeled DiI-OxLDL uptake in J774A.1 cells. Meanwhile, expression of the class A scavenger receptor (SR-A), a receptor for modified LDL, was also enhanced. Furthermore, pertussis toxin (PTx) or Ki16425 significantly abolished LPA's effects, indicating that G(i) and LPA(3) are involved in OxLDL uptake and SR-A expression. Of most importance, the LPA-induced OxLDL uptake could be inhibited when cells were incubated with a functional blocking antibody of SR-A. Our results suggest that LPA-enhanced OxLDL uptake is mediated via LPA(3)-G(i) activation and subsequent SR-A expression.
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Affiliation(s)
- Chi-Lun Chang
- Institute of Zoology, National Taiwan University, Taipei, Taiwan, ROC
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