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Olsson M, Stanne TM, Pedersen A, Lorentzen E, Kara E, MartinezâPalacian A, RÃnnow Sand NP, Jacobsen AF, Sandset PM, Sidelmann JJ, EngstrÃm G, Melander O, Kanse SM, Jern C. Genome-wide analysis of genetic determinants of circulating factor VII-activating protease (FSAP) activity. J Thromb Haemost 2018; 16:2024-2034. [PMID: 30070759 PMCID: PMC6485504 DOI: 10.1111/jth.14258] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2018] [Indexed: 01/17/2023]
Abstract
Essentials Knowledge of genetic regulators of plasma factor VII activating protease (FSAP) levels is limited. We performed a genome-wide analysis of variants influencing FSAP activity in Scandinavian cohorts. We replicated an association for Marburg-1 and identified an association for a HABP2 stop variant. We identified a novel locus near ADCY2 as a potential additional regulator of FSAP activity. SUMMARY Background Factor VII-activating protease (FSAP) has roles in both coagulation and fibrinolysis. Recent data indicate its involvement in several other processes, such as vascular remodeling and inflammation. Plasma FSAP activity is highly variable among healthy individuals and, apart from the low-frequency missense variant Marburg-I (rs7080536) in the FSAP-encoding gene HABP2, determinants of this variation are unclear. Objectives To identify novel genetic variants within and outside of the HABP2 locus that influence circulating FSAP activity. Patients/Methods We performed an exploratory genome-wide association study (GWAS) on plasma FSAP activity amongst 3230 Swedish subjects. Directly genotyped rare variants were also analyzed with gene-based tests. Using GWAS, we confirmed the strong association between the Marburg-I variant and FSAP activity. HABP2 was also significant in the gene-based analysis, and remained significant after exclusion of Marburg-I carriers. This was attributable to a rare HABP2 stop variant (rs41292628). Carriers of this stop variant showed a similar reduction in FSAP activity as Marburg-I carriers, and this finding was replicated. A secondary genome-wide significant locus was identified at a 5p15 locus (rs35510613), and this finding requires future replication. This common variant is located upstream of ADCY2, which encodes a protein catalyzing the formation of cAMP. Results and Conclusions This study verified the Marburg-I variant to be a strong regulator of FSAP activity, and identified an HABP2 stop variant with a similar impact on FSAP activity. A novel locus near ADCY2 was identified as a potential additional regulator of FSAP activity.
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Affiliation(s)
- M. Olsson
- Department of Pathology and GeneticsInstitute of BiomedicineThe Sahlgrenska Academy at University of GothenburgGothenburgSweden
| | - T. M. Stanne
- Department of Pathology and GeneticsInstitute of BiomedicineThe Sahlgrenska Academy at University of GothenburgGothenburgSweden
| | - A. Pedersen
- Department of Pathology and GeneticsInstitute of BiomedicineThe Sahlgrenska Academy at University of GothenburgGothenburgSweden
| | - E. Lorentzen
- Bioinformatics Core FacilityUniversity of GothenburgGothenburgSweden
| | - E. Kara
- Institute of Basic Medical SciencesFaculty of MedicineUniversity of OsloOsloNorway
| | - A. MartinezâPalacian
- Institute of Basic Medical SciencesFaculty of MedicineUniversity of OsloOsloNorway
| | - N. P. RÃnnow Sand
- Department of CardiologyHospital of South West DenmarkEsbjerg and Department of Regional Health ResearchFaculty of Health ScienceUniversity of Southern DenmarkEsbjergDenmark
| | - A. F. Jacobsen
- Department of ObstetricsOslo University Hospital and University of OsloOsloNorway
| | - P. M. Sandset
- Department of HematologyOslo University Hospital and University of OsloOsloNorway
| | - J. J. Sidelmann
- Unit for Thrombosis ResearchDepartment of Regional Health ResearchFaculty of Health ScienceUniversity of Southern DenmarkEsbjergDenmark
| | - G. EngstrÃm
- Department of Clinical Sciences, MalmÃLund UniversityLundSweden
| | - O. Melander
- Department of Clinical Sciences, MalmÃLund UniversityLundSweden
| | - S. M. Kanse
- Institute of Basic Medical SciencesFaculty of MedicineUniversity of OsloOsloNorway
| | - C. Jern
- Department of Pathology and GeneticsInstitute of BiomedicineThe Sahlgrenska Academy at University of GothenburgGothenburgSweden
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Preissner KT, May AE, Wohn KD, Germer M, Kanse SM. Molecular Crosstalk Between Adhesion Receptors and Proteolytic Cascades in Vascular Remodelling. Thromb Haemost 2018. [DOI: 10.1055/s-0038-1657507] [Citation(s) in RCA: 30] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
Affiliation(s)
| | - A E May
- Max-Planck-lnstitut, Bad Nauheim, Germany
| | - K D Wohn
- Max-Planck-lnstitut, Bad Nauheim, Germany
| | - M Germer
- Max-Planck-lnstitut, Bad Nauheim, Germany
| | - S M Kanse
- Max-Planck-lnstitut, Bad Nauheim, Germany
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Abstract
SummaryFactor VII activating protease (FSAP) is a circulating serine protease with high homology to fibrinolytic enzymes. A role in the regulation of coagulation and fibrinolysis is suspected based on in vitro studies demonstrating activation of FVII or pro-urokinase plasminogen activator (uPA). However, considering the paucity of any studies in animal models or any correlative studies in humans the role of FSAP in haemostasis remains unclear. In relation to vascular remodeling processes or inflammation it has been convincingly shown that FSAP interacts with growth factors as well as protease activated receptors (PAR). Against this sparse background there are a plethora of studies which have investigated the linkage of single nucleotide polymorphisms (SNP) in the FSAP gene (HABP2) to various diseases. The G534E SNP of FSAP is associated with a low proteolytic activity due to an amino acid exchange in the protease domain. This and other SNPs have been linked to carotid stenosis, stroke as well as thrombosis in the elderly and plaque calcification. These SNP analyses indicate an important role for FSAP in the regulation of the haemostasis system as well as fibroproliferative inflammatory processes.
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Daniel JM, Reichel CA, Schmidt-Woell T, Dutzmann J, Zuchtriegel G, Krombach F, Herold J, Bauersachs J, Sedding DG, Kanse SM. Factor VII-activating protease deficiency promotes neointima formation by enhancing leukocyte accumulation. J Thromb Haemost 2016; 14:2058-2067. [PMID: 27431088 DOI: 10.1111/jth.13417] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2015] [Accepted: 07/01/2016] [Indexed: 01/08/2023]
Abstract
Essentials Factor VII-activating protease (FSAP) is a plasma protease involved in vascular processes. Neointima formation was investigated after vascular injury in FSAP-/- mice. The neointimal lesion size and the accumulation of macrophages were increased in FSAP-/- mice. This was due to an increased activity of the chemokine (C-C motif) ligand 2 (CCL2). SUMMARY Background Factor VII-activating protease (FSAP) is a multifunctional circulating plasma serine protease involved in thrombosis and vascular remodeling processes. The Marburg I single-nucleotide polymorphism (MI-SNP) in the FSAP-coding gene is characterized by low proteolytic activity, and is associated with increased rates of stroke and carotid stenosis in humans. Objectives To determine whether neointima formation after vascular injury is increased in FSAP-/- mice. Methods and Results The neointimal lesion size and the proliferation of vascular smooth muscle cells (VSMCs) were significantly enhanced in FSAP-/- mice as compared with C57BL/6 control mice after wire-induced injury of the femoral artery. Accumulation of leukocytes and macrophages was increased within the lesions of FSAP-/- mice at day 3 and day 14. Quantitative zymography demonstrated enhanced activity of gelatinases/matrix metalloproteinase (MMP)-2 and MMP-9 within the neointimal lesions of FSAP-/- mice, and immunohistochemistry showed particular costaining of MMP-9 with accumulating leukocytes. Using intravital microscopy, we observed that FSAP deficiency promoted the intravascular adherence and the subsequent transmigration of leukocytes in vivo in response to chemokine ligand 2 (CCL2). CCL2 expression was increased in FSAP-/- monocytes but not in the vessel wall. There was no difference in the expression of platelet-derived growth factor (PDGF-BB). Conclusions FSAP deficiency causes an increase in CCL2 expression and CCL2-mediated infiltration of leukocytes into the injured vessel, thereby promoting SMC proliferation and migration by the activation of leukocyte-derived gelatinases. These results provide a possible explanation for the observed association of the loss-of-function MI-SNP with vascular proliferative diseases.
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Affiliation(s)
- J-M Daniel
- Department of Biochemistry, Justus-Liebig-Universität Giessen, Giessen, Germany
- Department of Cardiology and Angiology, Hannover Medical School, Hannover, Germany
| | - C A Reichel
- Department of Otorhinolaryngology, Head and Neck Surgery, Ludwig-Maximilians-Universität München, Munich, Germany
- Walter Brendel Center of Experimental Medicine, Ludwig-Maximilians-Universität München, Munich, Germany
| | - T Schmidt-Woell
- Department of Biochemistry, Justus-Liebig-Universität Giessen, Giessen, Germany
| | - J Dutzmann
- Department of Cardiology and Angiology, Hannover Medical School, Hannover, Germany
| | - G Zuchtriegel
- Department of Otorhinolaryngology, Head and Neck Surgery, Ludwig-Maximilians-Universität München, Munich, Germany
- Walter Brendel Center of Experimental Medicine, Ludwig-Maximilians-Universität München, Munich, Germany
| | - F Krombach
- Walter Brendel Center of Experimental Medicine, Ludwig-Maximilians-Universität München, Munich, Germany
| | - J Herold
- Department of Cardiology, Angiology and Pneumology, Otto-von-Guericke University Magdeburg, Magdeburg, Germany
| | - J Bauersachs
- Department of Cardiology and Angiology, Hannover Medical School, Hannover, Germany
| | - D G Sedding
- Department of Cardiology and Angiology, Hannover Medical School, Hannover, Germany
| | - S M Kanse
- Department of Biochemistry, Justus-Liebig-Universität Giessen, Giessen, Germany.
- Oslo University Hospital and University of Oslo, Oslo, Norway.
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Garcia-Martinez V, Lopez Sanchez C, Hamed W, Hamed W, Hsu JH, Ferrer-Lorente R, Alshamrani M, Pizzicannella J, Vindis C, Badi I, Korte L, Voellenkle C, Niculescu LS, Massaro M, Babaeva AR, Da Silva F, Woudstra L, Berezin A, Bae MK, Del Giudice C, Bageghni SA, Krobert K, Levay M, Vignier N, Ranieri A, Magenta A, Orlandi A, Porro B, Jeon ES, Omori Y, Herold J, Barnett GA, Grochot-Przeczek A, Korpisalo P, Deffge C, Margariti A, Rong W, Maring JA, Gambardella J, Mitrofan CG, Karpinska O, Morbidelli L, Wilkinson FL, Berezin A, Kostina AS, De Mey JGR, Kumar A, Lupieri A, Pellet-Many C, Stamatiou R, Gromotowicz A, Dickhout A, Murina M, Roka-Moiia YM, Malinova L, Diaz-Canestro C, Vigliarolo T, Cuzzocrea S, Szantai A, Medic B, Cassambai S, Korda A, Revnic CR, Borile G, Diokmetzidou A, Murfitt L, Budko A, Fiordelisi A, De Wijs-Meijler DPM, Gevaert AB, Noriega De La Colina A, Benes J, Guillermo Solache Berrocal GSB, Gafarov V, Zhebel VM, Prakaschandra R, Stepien EL, Smith LE, Carluccio MA, Timasheva Y, Paci M, Dorofeyeva NA, Chimed CH, Petelina TI, Sorop O, Genis A, Parepa IR, Tscharre M, Krestjyaninov MV, Maia-Rocha C, Borges L, Sasonko ML, Kapel SS, Stam K, Sommariva E, Stojkovic S, O'reilly J, Chiva-Blanch G, Malinova L, Evtushenko A, Skopal J, Sunderland N, Gegenava T, Charnaia MA, Di Lascio N, Tarvainen SJ, Malandraki-Miller S, Uitterdijk A, Benzoni P, Ruivo E, Humphrey EJ, Arokiaraj MC, Franco D, Garcia-Lopez V, Aranega A, Lopez-Sanchez C, Franco D, Garcia-Lopez V, Aranega A, Garcia-Martinez V, Tayel S, Khader H, El-Helbawy N, Tayel S, Alrefai A, El-Barbary H, Wu JR, Dai ZK, Yeh JL, Sanjurjo-Rodriguez C, Richaud-Patin Y, Blanco FJ, Badimon L, Raya A, Cahill PA, Diomede F, Merciaro I, Trubiani O, Nahapetyan H, Swiader A, Faccini J, Boya P, Elbaz M, Zeni F, Burba I, Bertolotti M, Capogrossi MC, Pompilio G, Raucci A, Widmer-Teske R, Dutzmann J, Bauersachs J, Donde K, Daniel JM, Sedding DG, Simionescu N, Sanda GM, Carnuta MG, Stancu CS, Popescu AC, Popescu MR, Vlad A, Dimulescu DR, Sima AV, Scoditti E, Pellegrino M, Calabriso N, Carluccio MA, Storelli C, De Caterina R, Solodenkova KS, Kalinina EV, Usachiova MN, Lappalainen J, Lee-Rueckert MDEC, Kovanen PT, Biesbroek PS, Emmens RWE, Van Rossum AC, Juffermans LJM, Niessen JWM, Krijnen PAJ, Kremzer A, Samura T, Berezina T, Gronenko E, Kim MK, Park HJ, Bae SK, Sorriento D, Ciccarelli M, Vernieri E, Campiglia P, Trimarco B, Iaccarino G, Hemmings KE, Porter KE, Ainscough JF, Drinkhill MJ, Turner NA, Hiis HG, Cosson MV, Levy FO, Wieland T, Macquart C, Chatzifrangkeskou M, Evans A, Bonne G, Muchir A, Kemp E, Avkiran M, Carlomosti F, D'agostino M, Beji S, Zaccagnini G, Maimone B, Di Stefano V, De Santa F, Cordisco S, Antonini A, Ciarapica R, Dellambra E, Martelli F, Avitabile D, Capogrossi MC, Scioli MG, Bielli A, Agostinelli S, Tarquini C, Tarallo V, De Falco S, Zaninoni A, Fiorelli S, Bianchi P, Teruzzi G, Squellerio I, Turnu L, Lualdi A, Tremoli E, Cavalca V, Lee YJ, Ju ES, Choi JO, Lee GY, Lim BK, Manickam MANOJ, Jung SH, Omiya S, Otsu K, Deffge C, Nowak S, Wagner M, Braun-Dullaeus RC, Kostin S, Daniel JM, Francke A, Subramaniam S, Kanse SM, Al-Lamee K, Schofield CJ, Egginton S, Gershlick AH, Kloska D, Kopacz A, Augustyniak A, Dulak J, Jozkowicz A, Hytonen J, Halonen P, Taavitsainen J, Tarvainen S, Hiltunen T, Liimatainen T, Kalliokoski K, Knuuti J, Yla-Herttuala S, Wagner M, Weinert S, Isermann B, Lee J, Braun-Dullaeus RC, Herold J, Cochrane A, Kelaini S, Bojdo J, Vila Gonzalez M, Hu Y, Grieve D, Stitt AW, Zeng L, Xu Q, Margariti A, Reglin B, Xiang W, Nitzsche B, Maibier M, Pries AR, Vrijsen KR, Chamuleau SAJ, Verhage V, Metz CHG, Lodder K, Van Eeuwijk ECM, Van Dommelen SM, Doevendans PA, Smits AM, Goumans MJ, Sluijter JPG, Sorriento D, Bova M, Loffredo S, Trimarco B, Iaccarino G, Ciccarelli M, Appleby S, Morrell N, Baranowska-Kuczko M, Kloza M, Ambrozewicz E, Kozlowski M, Malinowska B, Kozlowska H, Monti M, Terzuoli E, Ziche M, Mahmoud AM, Jones AM, Wilkinson JA, Romero M, Duarte J, Alexander MY, Kremzer A, Berezina T, Gronenko E, Faggian G, Kostareva AA, Malashicheva AB, Leurgans TM, Nguyen TN, Irmukhamedov A, Riber LP, Mcgeogh R, Comer S, Blanco Fernandez A, Ghigo A, Blaise R, Smirnova NF, Malet N, Vincent P, Limon I, Gayral S, Hirsch E, Laffargue M, Mehta V, Zachary I, Aidonidis I, Kramkowski K, Miltyk W, Kolodziejczyk P, Gradzka A, Szemraj J, Chabielska E, Dijkgraaf I, Bitsch N, Van Hoof S, Verhaegen F, Koenen R, Hackeng TM, Roshchupkin DI, Buravleva KV, Sergienko VI, Zhernossekov DD, Rybachuk VM, Grinenko TV, Furman N, Dolotovskaya P, Shamyunov M, Denisova T, Reiner M, Akhmedov A, Keller S, Miranda M, Briand S, Barile L, Kullak-Ublick G, Luscher T, Camici G, Guida L, Magnone M, Ameri P, Lazzarini E, Fresia C, Bruzzone S, Zocchi E, Di Paola R, Cordaro M, Crupi R, Siracusa R, Campolo M, Bruschetta G, Fusco R, Pugliatti P, Esposito E, Paloczi J, Ruivo E, Gaspar R, Dinnyes A, Kobolak J, Ferdinandy P, Gorbe A, Todorovic Z, Krstic D, Savic Vujovic K, Jovicic D, Basta Jovanovic G, Radojevic Skodric S, Prostran M, Dean S, Mee CJ, Harvey KL, Hussain A, Pena C, Paltineanu B, Voinea S, Revnic F, Ginghina C, Zaglia T, Ceriotti P, Campo A, Carullo P, Armani A, Coppini R, Vida V, Olivotto I, Stellin G, Rizzuto R, De Stefani D, Sandri M, Catalucci D, Mongillo M, Soumaka E, Kloukina I, Tsikitis M, Makridakis M, Varela A, Davos C, Vlachou A, Capetanaki Y, Iqbal MM, Bennett H, Davenport B, Pinali C, Cooper G, Cartwright E, Kitmitto A, Strutynska NA, Mys LA, Sagach VF, Franco A, Sorriento D, Trimarco B, Iaccarino G, Ciccarelli M, Verzijl A, Stam K, Van Duin R, Reiss IKM, Duncker DJ, Merkus D, Shakeri H, Orije M, Leloup AJ, Van Hove CE, Van Craenenbroeck EM, De Meyer GRY, Vrints CJ, Lemmens K, Desjardins-Creapeau L, Wu R, Lamarre-Cliche M, Larochelle P, Bherer L, Girouard H, Melenovsky M, Kvasilova A, Benes J, Ruskova K, Sedmera D, Ana Barral ABV, Martin Fernandez M, Pablo Roman Garcia PRG, Juan Carlos Llosa JCLL, Manuel Naves Diaz MND, Cesar Moris CM, Jorge B Cannata-Andia JBCA, Isabel Rodriguez IR, Voevoda M, Gromova E, Maximov V, Panov D, Gagulin I, Gafarova A, Palahniuk H, Pashkova IP, Zhebel NV, Starzhynska OL, Naidoo DP, Rawojc K, Enguita FJ, Grudzien G, Cordwell SJ, White MY, Massaro M, Scoditti E, Calabriso N, Pellegrino M, Martinelli R, Gatta V, De Caterina R, Nasibullin TR, Erdman VV, Tuktarova IA, Mustafina OE, Hyttinen J, Severi S, Vorobyov GG, Sagach VF, Batmyagmar KH, Lkhagvasuren Z, Gapon LI, Musikhina NA, Avdeeva KS, Dyachkov SM, Heinonen I, Van Kranenburg M, De Beer VJ, Octavia Y, Van Geuns RJ, Van Den Meiracker AH, Van Der Velden J, Merkus D, Duncker DJ, Everson FP, Ogundipe T, Grandjean T, De Boever P, Goswami N, Strijdom H, Suceveanu AI, Suceveanu AP, Mazilu L, Tofoleanu DE, Catrinoiu D, Rohla M, Hauser C, Huber K, Wojta H, Weiss TW, Melnikova MA, Olezov NV, Gimaev RH, Khalaf H, Ruzov VI, Adao R, Mendes-Ferreira P, Santos-Ribeiro D, Rademaker M, Leite-Moreira AF, Bras-Silva C, Alvarenga LAA, Falcao RSP, Dias RR, Lacchini S, Gutierrez PS, Michel JB, Gurfinkel YUI, Atkov OYU, Teichert M, Korn C, Mogler C, Hertel S, Arnold C, Korff T, Augustin HG, Van Duin RWB, De Wijs-Meijler DPM, Verzijl A, Duncker DJ, Merkus D, D'alessandra Y, Farina FM, Casella M, Catto V, Carbucicchio C, Dello Russso A, Stadiotti I, Brambilla S, Chiesa M, Giacca M, Colombo GI, Pompilio G, Tondo C, Ahlin F, Andric T, Tihanyi D, Wojta J, Huber K, O'connell E, Butt A, Murphy L, Pennington S, Ledwidge M, Mcdonald K, Baugh J, Watson C, Suades R, Crespo J, Estruch R, Badimon L, Dyachenko A, Ryabukho V, Evtushenko V, Saushkina YU, Lishmanov YU, Smyshlyaev K, Bykov A, Popov S, Pavlyukova E, Anfinogenova Y, Szigetfu E, Kapornai B, Forizs E, Jenei ZS, Nagy Z, Merkely B, Zima E, Cai A, Dworakowski R, Gibbs T, Piper S, Jegard N, Mcdonagh T, Gegenava M, Dementieva II, Morozov YUA, Barsanti C, Stea F, Lenzarini F, Kusmic C, Faita F, Halonen PJ, Puhakka PH, Hytonen JP, Taavitsainen JM, Yla-Herttuala S, Supit EA, Carr CA, Groenendijk BCW, Gorsse-Bakker C, Panasewicz A, Sneep S, Tempel D, Van Der Giessen WJ, Duncker DJ, Rys J, Daraio C, Dell'era P, Paloczi J, Pigler J, Eder A, Ferdinandy P, Eschenhagen T, Gorbe A, Mazo MM, Amdursky N, Peters NS, Stevens MM, Terracciano CM. Poster session 2Morphogenetic mechanisms290MiR-133 regulates retinoic acid pathway during early cardiac chamber specification291Bmp2 regulates atrial differentiation through miR-130 during early heart looping formationDevelopmental genetics294Association of deletion allele of insertion/deletion polymorphism in alpha 2B adrenoceptor gene and hypertension with or without type 2 diabetes mellitus295Association of G1359A polymorphism of the endocannabinoid type 1 receptor (CNR1) with coronary artery disease (CAD) with type 2 diabetes mellitusCell growth, differentiation and stem cells - Vascular298Gamma-secretase inhibitor prevents proliferation and migration of ductus arteriosus smooth muscle cells: a role of Notch signaling in postnatal closure of ductus arteriosus299Mesenchymal stromal-like cells (MLCs) derived from induced pluripotent stem (iPS) cells: a promising therapeutic option to promote neovascularization300Sonic Hedgehog promotes mesenchymal stem cell differentiation to vascular smooth muscle cells in cardiovacsular disease301Proinflammatory cytokine secretion and epigenetic modification in endothelial cells treated LPS-GinfivalisCell death and apoptosis - Vascular304Mitophagy acts as a safeguard mechanism against human vascular smooth muscle cell apoptosis induced by atherogenic lipidsTranscriptional control and RNA species - Vascular307MicroRNA-34a role in vascular calcification308Local delivery of a miR-146a inhibitor utilizing a clinically applicable approach attenuates neointima formation after vascular injury309Long noncoding RNA landscape of hypoxic endothelial cells310Specific circulating microRNAs levels associate with hypertension, hyperglycemia and dysfunctional HDL in acute coronary syndrome patientsCytokines and cellular inflammation - Vascular313Phosphodiesterase5A up-regulation in vascular endothelium under pro-inflammatory conditions: a newly disclosed anti-inflammatory activity for the omega-3polyunsaturated aatty acid docosahexaenoic acid314Cardiovascular risk modifying with extra-low dose anticytokine drugs in rhematoid arthritis315Conversion of human M-CSF macrophages into foam cells reduces their proinflammatory responses to classical M1-polarizing activation316Lymphocytic myocarditis coincides with increased plaque inflammation and plaque hemorrhage in coronary arteries, facilitating myocardial infarction317Serum osteoprotegerin level predictsdeclined numerous of circulating endothelial- derived and mononuclear-derived progenitor cells in patients with metabolic syndromeGrowth factors and neurohormones - Vascular320Effect of gastrin-releasing peptide (GRP) on vascular inflammationSignal transduction - Heart323A new synthetic peptide regulates hypertrophy in vitro through means of the inhibition of nfkb324Inducible fibroblast-specific knockout of p38 alpha map kinase is cardioprotective in a mouse model of isoproterenol-induced cardiac hypertrophy325Regulation of beta-adrenoceptor-evoked inotropic responses by inhibitory G protein, adenylyl cyclase isoforms 5 and 6 and phosphodiesterases326Binding to RGS3 and stimulation of M2 muscarinic acetylcholine receptors modulates the substrate specificity of p190RhoGAP in cardiac myocytes327Cardiac regulation of post-translational modifications, parylation and deacetylation in LMNA dilated cardiomyopathy mouse model328Beta-adrenergic regulation of the b56delta/pp2a holoenzyme in cardiac myocytes through b56delta phosphorylation at serine 573Nitric oxide and reactive oxygen species - Vascular331Oxidative stress-induced miR-200c disrupts the regulatory loop among SIRT1, FOXO1 and eNOS332Antioxidant therapy prevents oxidative stress-induced endothelial dysfunction and Enhances Wound Healing333Morphological and biochemical characterization of red blood cell in coronary artery diseaseCytoskeleton and mechanotransduction - Heart336Novel myosin activator, JSH compounds, increased myocardial contractility without chronotropic effect in ratsExtracellular matrix and fibrosis - Vascular339Ablation of Toll-like receptor 9 causes cardiac rupture after myocardial infarction by attenuating proliferation and differentiation of cardiac fibroblasts340Altered vascular remodeling in the mouse hind limb ischemia model in Factor VII activating protease (FSAP) deficiencyVasculogenesis, angiogenesis and arteriogenesis343Pro-angiogenic effects of proly-hydroxylase inhibitors and their potential for use in a novel strategy of therapeutic angiogenesis for coronary total occlusion344Nrf2 drives angiogenesis in transcription-independent manner: new function of the master regulator of oxidative stress response345Angiogenic gene therapy, despite efficient vascular growth, is not able to improve muscle function in normoxic or chronically ischemic rabbit hindlimbs -role of capillary arterialization and shunting346Effect of PAR-1 inhibition on collateral vessel growth in the murine hind limb model347Quaking is a key regulator of endothelial cell differentiation, neovascularization and angiogenesis348"Emerging angiogenesis" in the chick chorioallantoic membrane (CAM). An in vivo study349Exosomes from cardiomyocyte progenitor cells and mesenchymal stem cells stimulate angiogenesis in vitro and in vivo via EMMPRINEndothelium352Reciprocal regulation of GRK2 and bradykinin receptor stimulation modulate Ca2+ intracellular level in endothelial cells353The roles of bone morphogenetic proteins 9 and 10 in endothelial inflammation and atherosclerosis354The contribution of GPR55 to the L-alpha-lysophosphatidylinositol-induced vasorelaxation in isolated human pulmonary arteries355The endothelial protective ACE inhibitor Zofenoprilat exerts anti-inflammatory activities through H2S production356A new class of glycomimetic drugs to prevent free fatty acid-induced endothelial dysfunction357Endothelial progenitor cells to apoptotic endothelial cell-derived microparticles ration differentiatesas preserved from reduced ejection fractionheart failure358Proosteogenic genes are activated in endothelial cells of patients with thoracic aortic aneurysm359Endothelin ETB receptors mediate relaxing responses to insulin in pericardial resistance arteries from patients with cardiovascular disease (CVD)Smooth muscle and pericytes362CX3CR1 positive myeloid cells regulate vascular smooth muscle tone by inducing calcium oscillations via activation of IP3 receptors363A novel function of PI3Kg on cAMP regulation, role in arterial wall hyperplasia through modulation of smooth muscle cells proliferation364NRP1 and NRP2 play important roles in the development of neointimal hyperplasia in vivo365Azithromycin induces autophagy in aortic smooth muscle cellsCoagulation, thrombosis and platelets368The real time in vivo evaluation of platelet-dependent aldosterone prothrombotic action in mice369Development of a method for in vivo detection of active thrombi in mice370The antiplatelet effects of structural analogs of the taurine chloramine371The influence of heparin anticoagulant drugs on functional state of human platelets372Regulation of platelet aggregation and adenosine diphosphate release by d dimer in acute coronary syndrome (in vitro study)Oxygen sensing, ischaemia and reperfusion375Sirtuin 5 mediates brain injury in a mouse model of cerebral ischemia-reperfusion376Abscisic acid: a new player in cardiomyocyte protection from ischaemia?377Protective effects of ultramicronized palmitoylethanolamide (PEA-um) in myocardial ischaemia and reperfusion injury in vivo378Identification of stem cell-derived cardiomyocytes using cardiac specific markers and additional testing of these cells in simulated ischemia/reperfusion system379Single-dose intravenous metformin treatment could afford significant protection of the injured rat kidney in an experimental model of ischemia-reperfusion380Cardiotoxicity of long acting muscarinic receptor antagonists used for chronic obstructive pulmonary disease381Dependence antioxidant potential on the concentration of amino acids382The impact of ischemia-reperfusion on physiological parameters,apoptosis and ultrastructure of rabbit myocardium with experimental aterosclerosisMitochondria and energetics385MicroRNA-1 dependent regulation of mitochondrial calcium uniporter (MCU) in normal and hypertrophied hearts386Mitochondrial homeostasis and cardioprotection: common targets for desmin and aB-crystallin387Overexpression of mitofusin-2 (Mfn2) and associated mitochondrial dysfunction in the diabetic heart388NO-dependent prevention of permeability transition pore (MPTP) opening by H2S and its regulation of Ca2+ accumulation in rat heart mitochondria389G protein coupled receptor kinase 2 (GRK2) is fundamental in recovering mitochondrial morphology and function after exposure to ionizing radiation (IR)Gender issues392Sex differences in pulmonary vascular control; focus on the nitric oxide pathwayAging395Heart failure with preserved ejection fraction develops when feeding western diet to senescence-accelerated mice396Cardiovascular markers as predictors of cognitive decline in elderly hypertensive patients397Changes in connexin43 in old rats with volume overload chronic heart failureGenetics and epigenetics400Calcium content in the aortic valve is associated with 1G>2G matrix metalloproteinase 1 polymorphism401Neuropeptide receptor gene s (NPSR1) polymorphism and sleep disturbances402Endothelin-1 gene Lys198Asn polymorphism in men with essential hypertension complicated and uncomplicated with chronic heart failure403Association of common polymorphisms of the lipoprotein lipase and pon1 genes with the metabolic syndrome in a sample of community participantsGenomics, proteomics, metabolomics, lipidomics and glycomics405Gene expression quantification using multiplexed color-coded probe pairs to determine RNA content in sporadic cardiac myxoma406Large-scale phosphorylation study of the type 2 diabetic heart subjected to ischemia / reperfusion injury407Transcriptome-based identification of new anti-inflammatory properties of the olive oil hydroxytyrosol in vascular endothelial cell under basal and proinflammatory conditions408Gene polymorphisms combinations and risk of myocardial infarctionComputer modelling, bioinformatics and big data411Comparison of the repolarization reserve in three state-of-the-art models of the human ventricular action potentialMetabolism, diabetes mellitus and obesity414Endothelial monocyte-activating polypeptide-II improves heart function in type -I Diabetes mellitus415Admission glucose level is independent predictor of impaired left ventricular function in patients with acute myocardial infarction: a two dimensional speckle-tracking echocardiography study416Association between biochemical markers of lipid profile and inflammatory reaction and stiffness of the vascular wall in hypertensive patients with abdominal obesity417Multiple common co-morbidities produce left ventricular diastolic dysfunction associated with coronary microvascular dysfunction, oxidative stress and myocardial stiffening418Investigating the cardiovascular effects of antiretroviral drugs in a lean and high fat/sucrose diet rat model of obesity419Statins in the treatment of non-alcoholic steatohepatitis (NASH). Our experience from a 2-year prospective study in Constanta County, Romania420Epicardial adipose tissue as a predictor of cardiovascular outcome in patients with ACS undergoing PCI?Arterial and pulmonary hypertension423Dependence between heart rhythm disorers and ID polymorphism of ACE gene in hypertensive patients424Molecular mechanisms underlying the beneficial effects of Urocortin 2 in pulmonary arterial hypertension425Inhibition of TGf-b axis and action of renin-angiotensin system in human ascending aorta aneurysms426Early signs of microcirculation and macrocirculation abnormalities in prehypertension427Vascular smooth muscle cell-expressed Tie-2 controls vascular tone428Cardiac and vascular remodelling in the development of chronic thrombo-embolic pulmonary hypertension in a novel swine modelBiomarkers431Arrhythmogenic cardiomyopathy: a new, non invasive biomarker432Can circulating microRNAs distinguish type 1 and type 2 myocardial infarction?433Design of a high-throughput multiplex proteomics assay to identify left ventricular diastolic dysfunction in diabetes434Monocyte-derived and P-selectin-carrying microparticles are differently modified by a low fat diet in patients with cardiovascular risk factors who will and who will not develop a cardiovascular event435Red blood cell distribution width assessment by polychromatic interference microscopy of thin films in chronic heart failure436Invasive and noninvasive evaluation of quality of radiofrequency-induced cardiac denervation in patients with atrial fibrillation437The effect of therapeutic hypothermia on the level of brain derived neurotrophic factor (BDNF) in sera following cardiopulmonary resustitation438Novel biomarkers to predict outcome in patients with heart failure and severe aortic stenosis439Biological factors linking depression and anxiety to cardiovascular disease440Troponins and myoglobin dynamic at coronary arteries graftingInvasive, non-invasive and molecular imaging443Diet composition effects on the genetic typing of the mouse ob mutation: a micro-ultrasound characterization of cardiac function, macro and micro circulation and liver steatosis444Characterization of pig coronary and rabbit aortic lesions using IV-OCT quantitative analysis: correlations with histologyGene therapy and cell therapy447Enhancing the survival and angiogenic potential of mouse atrial mesenchymal cells448VCAM-1 expression in experimental myocardial infarction and its relation to bone marrow-derived mononuclear cell retentionTissue engineering451Advanced multi layered scaffold that increases the maturity of stem cell-derived human cardiomyocytes452Response of engineered heart tissue to simulated ischemia/reperfusion in the presence of acute hyperglycemic conditions453Serum albumin hydrogels prevent de-differentiation of neonatal cardiomyocytes454A novel paintbrush technique for transfer of low viscosity ultraviolet light curable cyan methacrylate on saline immersed in-vitro sheep heart. Cardiovasc Res 2016. [DOI: 10.1093/cvr/cvw149] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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Joshi AU, Orset C, Engelhardt B, Baumgart-Vogt E, Gerriets T, Vivien D, Kanse SM. Deficiency of Factor VII activating protease alters the outcome of ischemic stroke in mice. Eur J Neurosci 2015; 41:965-75. [DOI: 10.1111/ejn.12830] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2014] [Revised: 12/08/2014] [Accepted: 12/10/2014] [Indexed: 01/29/2023]
Affiliation(s)
- A. U. Joshi
- Institute for Biochemistry; Justus-Liebig-University; Giessen Germany
- Chemical & Systems Biology; School of Medicine; Stanford University; Stanford CA USA
| | - C. Orset
- Inserm; Inserm UMR-S U919; Serine Proteases and Pathophysiology of the Neurovascular Unit; Université de Caen Basse-Normandie, GIP Cyceron; Caen France
| | - B. Engelhardt
- Theodor Kocher Institute; University of Bern; Bern Switzerland
| | - E. Baumgart-Vogt
- Institute of Anatomy and Cell Biology; Justus-Liebig-University; Giessen Germany
| | - T. Gerriets
- Department of Neurology; Justus-Liebig-University; Giessen Germany
| | - D. Vivien
- Inserm; Inserm UMR-S U919; Serine Proteases and Pathophysiology of the Neurovascular Unit; Université de Caen Basse-Normandie, GIP Cyceron; Caen France
| | - S. M. Kanse
- Institute for Biochemistry; Justus-Liebig-University; Giessen Germany
- Institute for Basic Medical Sciences; University of Oslo; Sognvannsveien 9 Oslo 0372 Norway
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Hanson E, Kanse SM, Joshi A, Jood K, Nilsson S, Blomstrand C, Jern C. Plasma factor VII-activating protease antigen levels and activity are increased in ischemic stroke. J Thromb Haemost 2012; 10:848-56. [PMID: 22409238 DOI: 10.1111/j.1538-7836.2012.04692.x] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
BACKGROUND Factor VII-activating protease (FSAP) is a recently discovered plasma protease with a role in the regulation of hemostasis and vascular remodeling processes. Higher levels and activity of FSAP have been reported in patients with deep vein thrombosis, but there are no data on plasma FSAP in ischemic stroke (IS). OBJECTIVE To investigate whether FSAP antigen levels and activity are associated with IS and/or etiologic subtypes of IS. PATIENTS AND METHODS To assess the potential association between FSAP and IS, plasma FSAP antigen levels and activity were measured in 600 consecutive IS patients and 600 population-based controls from the case-control study the Sahlgrenska Academy Study on Ischemic Stroke (SAHLSIS). Blood sampling was performed in the acute phase and 3 months after the index stroke. FSAP was also investigated at the genetic level by genotyping of 33 single-nucleotide polymorphisms. RESULTS Increased FSAP antigen level and activity, at both time-points, were independently associated with IS. Subtype analysis revealed similar associations for both FSAP measures, at both time-points, in all main IS subtypes. FSAP genotypes showed association with both FSAP plasma measurements, but not with IS. CONCLUSIONS Increased plasma FSAP antigen levels and activity were associated with IS and all main etiologic subtypes, suggesting a possible role for FSAP in the pathophysiology of IS, irrespective of the underlying etiology.
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Affiliation(s)
- E Hanson
- Institute of Neuroscience and Physiology, Department of Clinical Neuroscience and Rehabilitation, Sahlgrenska Academy at University of Gothenburg, Gothenburg, Sweden
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Baeten KM, Richard MC, Kanse SM, Mutch NJ, Degen JL, Booth NA. Activation of single-chain urokinase-type plasminogen activator by platelet-associated plasminogen: a mechanism for stimulation of fibrinolysis by platelets. J Thromb Haemost 2010; 8:1313-22. [PMID: 20180903 DOI: 10.1111/j.1538-7836.2010.03813.x] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
BACKGROUND AND OBJECTIVE Platelets are essential for hemostasis, and they cause resistance to fibrinolysis by tissue-type plasminogen activator. In contrast, platelets enhance fibrinolysis mediated by single-chain urokinase-type plasminogen activator (scu-PA). This study investigated the mechanism behind this profibrinolytic role of platelets. METHODS AND RESULTS Platelets enhanced scu-PA activity, but not urokinase-type plasminogen activator (u-PA) activity, in plasma clot lysis and chromogenic assays. We established, using the non-cleavable scu-PA mutant (Lys158-->Glu) and protease inhibitors, that platelets increased activation to u-PA by a serine protease. Activation of scu-PA was platelet-dependent, even in plasma. It occurred in platelet-rich but not in platelet-poor plasma, as assessed by sodium dodecylsulfate polyacrylamide gel electrophoresis and zymography after addition of plasminogen activator inhibitor-1. Candidate proteases that are known to activate scu-PA and are present in platelet preparations were investigated. Factor VII activating protease was detected in platelet preparations by western blotting, but its inhibition by antibodies did not inhibit activation of scu-PA by platelets. Plasmin and plasma kallikrein both mimicked the platelet effect, but were distinguished by their responses to a range of inhibitors. Analysis of platelet-associated protease activity and the time course of scu-PA activation pointed towards plasminogen, and the data were consistent with a mechanism of reciprocal activation. The essential role of plasminogen was revealed using platelets from plasminogen-deficient mice, which could not activate scu-PA. Local plasminogen on platelet membranes was markedly more effective than solution-phase plasminogen in activation of scu-PA. CONCLUSIONS Platelets enhance fibrinolysis by scu-PA through reciprocal activation of scu-PA and platelet-associated plasminogen, a system that is potentially important in the lysis of platelet-rich thrombi.
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Affiliation(s)
- K M Baeten
- Institute of Medical Sciences, University of Aberdeen, Aberdeen, UK
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Affiliation(s)
- S M Kanse
- Institute for Biochemistry, Justus-Liebig-University, Giessen, Germany.
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Deindl E, Ziegelhöffer T, Kanse SM, Fernandez B, Neubauer E, Carmeliet P, Preissner KT, Schaper W. Receptor-independent role of the urokinase-type plasminogen activator during arteriogenesis. FASEB J 2003; 17:1174-6. [PMID: 12692088 DOI: 10.1096/fj.02-0800fje] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
To define the role of the plasminogen activators (PAs) urokinase PA (uPA) and tissue PA (tPA) as well as the uPA receptor (uPAR) in arteriogenesis, we investigated their impact in a rabbit and mouse model of adaptive collateral artery growth. Collateral artery growth was induced by occlusion of the femoral artery in rabbit and wild-type (WT) mice and in mice with targeted inactivation of uPA (uPA-/-), tPA (tPA-/-), or uPAR (uPAR-/-). Northern blot results revealed a significant up-regulation of uPA but not uPAR or tPA in the early phase of arteriogenesis in rabbit and WT mice. This up-regulation on RNA level was followed by an increased protein level and enzymatic activity. Impaired perfusion recovery upon femoral artery ligation was observed by laser Doppler analysis in vivo in uPA-deficient mice but not in uPAR or tPA deficiency compared with WT mice. Immunohistochemical studies revealed an association of leukocyte infiltration with arteriogenesis in WT mice that was strongly reduced in uPA-/- but not in uPAR- or tPA-deficient mice. We conclude that arteriogenesis is promoted by an uPA-mediated infiltration of leukocytes that is not dependent on uPAR.
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Affiliation(s)
- E Deindl
- Max-Planck-Institute, Department of Exp. Cardiology, Benekestrasse 2, D-61231 Bad Nauheim, Germany.
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Chavakis T, Kanse SM, May AE, Preissner KT. Haemostatic factors occupy new territory: the role of the urokinase receptor system and kininogen in inflammation. Biochem Soc Trans 2002; 30:168-173. [PMID: 12023845] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
Vascular cell adhesion and migration, proliferation or differentiation are cellular responses that are induced by haemostatic factors of the urokinase/plasminogen activation complex, but the respective underlying mechanisms are largely undefined. The direct and indirect contributions of the urokinase-type plasminogen activator receptor (uPAR) system in inflammatory processes, as they relate to recruitment of leukocytes, define novel functions and could serve as therapeutic targets for related vasculopathies. The presence of uPAR plays a crucial role in beta2-integrin-mediated adhesion of leukocytes; uPAR also directly mediates leukocyte adhesion to vitronectin, a multifunctional adhesion protein that is associated with the extracellular matrix. The latter process is inhibited by plasminogen activator inhibitor-1. Both beta2-integrin- and uPAR-dependent processes are activated by Zn2+ and are blocked by high-molecular-mass kininogen. Domain 5 of kininogen was identified, in particular, as an anti-adhesive component with a potent anti-inflammatory action in a peritonitis mouse model. In patients with acute myocardial infarction, elevated expression of uPAR on monocytes resulted in their increased adherence to the endothelium, which indicates a possible role of the uPAR system in monocyte recruitment to the infarcted area. Urokinase-type plasminogen activator was identified as a potent mitogen for vascular smooth muscle cells, an observation that was independent of the presence of uPAR and its proteolytic activity. Taken together, these results strongly suggest an essential role for the uPAR system in acute inflammation as well as in chronic degenerative vascular processes such as atherosclerosis. Targeting the uPAR system may allow specific therapeutic intervention in vascular pathologies.
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Affiliation(s)
- T Chavakis
- Institut für Biochemie, Fachbereich Humanmedizin, Justus-Liebig-Universität, Friedrichstrasse 24, D-35392 Giessen, Germany
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Chavakis T, Kanse SM, Pixley RA, May AE, Isordia-Salas I, Colman RW, Preissner KT. Regulation of leukocyte recruitment by polypeptides derived from high molecular weight kininogen. FASEB J 2001; 15:2365-76. [PMID: 11689462 DOI: 10.1096/fj.01-0201com] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Proteolytic cleavage of single-chain, high molecular weight kininogen (HK) by kallikrein releases the short-lived vasodilator bradykinin and leaves behind a two-chain, high molecular weight kininogen (HKa) reported to bind to the beta2-integrin Mac-1 (CR3, CD11b/CD18, alphaMbeta2) on neutrophils and exert antiadhesive properties by binding to the urokinase receptor (uPAR) and vitronectin. We define the molecular mechanisms for the antiadhesive effects of HK related to disruption of beta2-integrin-mediated cellular interactions in vitro and in vivo. In a purified system, HK and HKa inhibited the binding of soluble fibrinogen and ICAM-1 to immobilized Mac-1, but not the binding of ICAM-1 to immobilized LFA-1 (CD11a/CD18, alphaLbeta2). This inhibitory effect could be attributed to HK domain 5 and to a lesser degree to HK domain 3, consistent with the requirement of both domains for binding to Mac-1. Accordingly, HK, HKa, and domain 5 inhibited the adhesion of Mac-1 but not LFA-1-transfected K562 human erythroleukemic cells to ICAM-1. Moreover, adhesion of human monocytic cells to fibrinogen and to human endothelial cells was blocked by HK, HKa, and domain 5. By using peptides derived from HK domain 5, the sequences including amino acids H475-G497 (and to a lesser extent, G440-H455) were identified as responsible for the antiadhesive effect, which was independent of uPAR. Finally, administration of domain 5 into mice, followed by induction of thioglycollate-provoked peritonitis, decreased the recruitment of neutrophils by approximately 70% in this model of acute inflammation. Taken together, HKa (and particularly domain 5) specifically interacts with Mac-1 but not with LFA-1, thereby blocking Mac-1-dependent leukocyte adhesion to fibrinogen and endothelial cells in vitro and in vivo and serving as a novel endogenous regulator of leukocyte recruitment into the inflamed tissue.
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Affiliation(s)
- T Chavakis
- Institute for Biochemistry, and, Third Department of Internal Medicine, Justus-Liebig-Universität, Giessen, Germany.
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Abstract
The interaction between urokinase plasminogen activator (uPA) and its cellular receptor (uPAR) is a key event in cell surface-associated plasminogen activation, relevant for cell migration and invasion. In order to define receptor recognition sites for uPA, we have expressed uPAR fragments as fusion products with the minor coat protein on the surface of M13 bacteriophages. Sequence analysis of cDNA fragments encoding uPA-binding peptides indicated the existence of a composite uPA-binding structure including all three uPAR domains. This finding was confirmed by experiments using an overlapping 15-mer peptide array covering the entire uPAR molecule. Four regions within the uPAR sequence were found to directly bind to uPA: two distinct regions containing amino acids 13--20 and amino acids 74--84 of the uPAR domain I, and regions in the putative loop 3 of the domains II and III. All the uPA-binding fragments from the three domains were shown to have an agonistic effect on uPA binding to immobilized uPAR. Furthermore, uPAR-(154--176) increased uPAR-transfected BAF3-cell adhesion on vitronectin in the presence of uPA, whereas uPAR-(247--276) stimulated the cell adhesion both in the absence or presence of uPA. The latter fragment was also able to augment the binding of vitronectin to uPAR in a purified system, thereby mimicking the effect of uPA on this interaction. These results indicate that uPA binding can take place to particular part(s) on several uPAR molecules and that direct uPAR-uPAR contacts may contribute to receptor activation and ligand binding.
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Affiliation(s)
- O D Liang
- Institut für Biochemie, Fachbereich Humanmedizin, Justus-Leipzig-Universität, Giessen, Germany
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Chavakis T, Willuweit AK, Lupu F, Preissner KT, Kanse SM. Release of soluble urokinase receptor from vascular cells. Thromb Haemost 2001; 86:686-93. [PMID: 11522023] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/21/2023]
Abstract
Urokinase-type plasminogen activator (uPA) and its cell surface-receptor (uPAR) regulate cellular functions linked to adhesion and migration and contribute to pericellular proteolysis in tissue remodelling processes. Soluble uPAR (suPAR) is present in the circulation, peritoneal and ascitic fluid and in the cystic fluid from ovarian cancer. We have investigated the origin and the vascular distribution of the soluble receptor, which accounts for 10-20% of the total receptor in vascular endothelial and smooth muscle cells. Phase separation analysis of the cell conditioned media with Triton X-114 indicated that suPAR associates with the aqueous phase, indicative of the absence of the glycolipid anchor. There was a polarized release of suPAR from cultured endothelial cells towards the basolateral direction, whereas the membrane-bound receptor was found preferentially on the apical surface. Both, uPAR and suPAR became upregulated 2-4 fold after activation of protein kinase C with phorbol ester, which required de-novo protein biosynthesis. Interleukin-1beta (IL-1beta), basic fibroblast growth factor (bFGF) or vascular endothelial growth factor increased suPAR release from endothelial cells, whereas platelet derived growth factor-BB, bFGF or IL-1beta stimulated suPAR release from vascular smooth muscle cells. Immune electron microscopy indicated that in atherosclerotic vessels (s)uPAR was observed on cell membranes as well as in the extracellular matrix. These findings indicate that (s)uPAR from vascular cells is upregulated by proangiogenic as well as proatherogenic growth factors and cytokines, is preferentially released towards the basolateral side of endothelial cells and accumulates in the vessel wall.
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MESH Headings
- Arteriosclerosis/metabolism
- Arteriosclerosis/pathology
- Cell Culture Techniques
- Cell Membrane/chemistry
- Cell Polarity
- Culture Media, Conditioned/analysis
- Endothelium, Vascular/cytology
- Endothelium, Vascular/drug effects
- Endothelium, Vascular/metabolism
- Growth Substances/pharmacology
- Humans
- Microscopy, Electron
- Muscle, Smooth, Vascular/cytology
- Muscle, Smooth, Vascular/drug effects
- Muscle, Smooth, Vascular/metabolism
- Phorbol Esters/pharmacology
- Plasminogen Activators/biosynthesis
- Plasminogen Activators/chemistry
- Plasminogen Activators/metabolism
- Receptors, Cell Surface/biosynthesis
- Receptors, Cell Surface/chemistry
- Receptors, Cell Surface/metabolism
- Receptors, Urokinase Plasminogen Activator
- Solubility
- Up-Regulation/drug effects
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Affiliation(s)
- T Chavakis
- Biochemisches Institut, Fachbereich Humanmedizin, Giessen, Germany
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Abstract
In a variety of cell types, the glycolipid-anchored urokinase receptor (uPAR) is colocalized pericellularly with components of the plasminogen activation system and endocytosis receptors. uPAR is also coexpressed with caveolin and members of the integrin adhesion receptor superfamily. The formation of functional units with these various proteins allows the uPAR to mediate the focused proteolysis required for cell migration and invasion and to contribute both directly and indirectly to cell adhesive processes in a non-proteolytic fashion. This dual activity, together with the initiation of signal transduction pathways by uPAR, is believed to influence cellular behaviour in angiogenesis, inflammation, wound repair and tumor progression/metastasis and open up the way for uPAR-based therapeutic approaches.
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Affiliation(s)
- K T Preissner
- Institut für Biochemie, Fachbereich Humanmedizin, Justus-Liebig-Universität, Friedrichstrasse 24, D-35392, Giessen, Germany.
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Chavakis T, Kanse SM, Lupu F, Hammes HP, Müller-Esterl W, Pixley RA, Colman RW, Preissner KT. Different mechanisms define the antiadhesive function of high molecular weight kininogen in integrin- and urokinase receptor-dependent interactions. Blood 2000; 96:514-22. [PMID: 10887113] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/17/2023] Open
Abstract
Proteolytic cleavage of single-chain high molecular weight kininogen (HK) by kallikrein releases the short-lived vasodilator bradykinin and leaves behind 2-chain high molecular weight kininogen (HKa) that has been previously reported to exert antiadhesive properties as well as to bind to the urokinase receptor (uPAR) on endothelial cells. In this study we defined the molecular mechanisms for the antiadhesive effects of HKa related to disruption of integrin- and uPAR-mediated cellular interactions. Vitronectin (VN) but not fibrinogen or fibronectin-dependent alphavbeta(3) integrin-mediated adhesion of endothelial cells was blocked by HKa or its isolated domain 5. In a purified system, HKa but not HK competed for the interaction of VN with alphavbeta(3) integrin, because HKa and the isolated domain 5 but not HK bound to both multimeric and native VN in a Zn(2+)-dependent manner. The interaction between HKa or domain 5 with VN was prevented by heparin, plasminogen activator inhibitor-1, and a recombinant glutathione-S-transferase (GST)-fusion peptide GST-VN (1-77) consisting of the amino terminal portion of VN (amino acids 1-77), but not by a cyclic arginyl-glycyl-aspartyl peptide, indicating that HKa interacts with the amino terminal portion of VN ("somatomedin B region"). Furthermore, we have confirmed that HKa but not HK bound to uPAR and to the truncated 2-domain form of uPAR lacking domain 1 in a Zn(2+)-dependent manner. Through these interactions, HKa or its recombinant His-Gly-Lys-rich domain 5 completely inhibited the uPAR-dependent adhesion of myelomonocytic U937 cells and uPAR-transfected BAF-3 cells to VN and thereby promoted cell detachment. By immunogold electron microscopy, both VN and HK/HKa were found to be colocalized in sections from human atherosclerotic coronary artery, indicating that the described interactions are likely to take place in vivo. Taken together, HK and HKa inhibit different VN-responsive adhesion receptor systems and may thereby influence endothelial cell- or leukocyte-related interactions in the vasculature, particularly under inflammatory conditions. (Blood. 2000;96:514-522)
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Affiliation(s)
- T Chavakis
- Institute for Biochemistry and the Department of Internal Medicine, Justus-Liebig-University, Giessen, Germany
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Abstract
The endothelium plays a crucial dynamic role as a protective interface between blood and the underlying tissues during the haemostatic process, which maintains blood flow in the circulation and prevents life-threatening blood loss. Following vessel wall injury with initial platelet adhesion and aggregation to exposed subendothelial extracellular matrix, the initiation, amplification, and control of haemostasis depend on structurally unrelated membrane-associated receptors for blood coagulation proteases including tissue factor, G-protein-coupled protease-activatable receptors, thrombomodulin, and protein C receptor, respectively. In addition to their regulatory role in haemostasis, the respective (pro-)enzyme ligands such as Factors VIIa and Xa, thrombin or protein C mediate specific signalling pathways in vascular cells related to migration, proliferation or adhesion. The functional importance of these receptors beyond haemostasis has been manifested by various lethal and pathological phenotypes in knock-out mice. These protease receptors thereby provide important molecular links in the vascular system and serve to integrate haemostasis with endothelial cell functions which are relevant for the (patho-)physiological responses to injury or inflammatory challenges.
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Affiliation(s)
- K T Preissner
- Institut für Biochemie, Fachbereich Humanmedizin, Justus-Liebig-Universität, D-35392 Giessen, Germany.
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Preissner KT, Kanse SM, Chavakis T, May AE. The dual role of the urokinase receptor system in pericellular proteolysis and cell adhesion: implications for cardiovascular function. Basic Res Cardiol 1999; 94:315-21. [PMID: 10543306 DOI: 10.1007/s003950050157] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Cell-cell and cell-matrix interactions are key events in morphogenetic processes during development and tissue remodelling. In the vascular system, overexpression of adhesion receptors such as integrins, protease (receptors) or dysregulation of adhesive interactions are directly related to the pathophysiology of cardiovascular diseases (atherosclerosis, restenosis, thrombosis) or angiogenesis-driven tumor progression. Protease cascades such as the plasminogen activation system exhibit a dual role in cell invasion by promoting pericellular proteolysis as well as by regulating cell adhesion and migration in a non-proteolytic fashion. In both these mechanisms, the urokinase receptor (uPAR) plays a central role and may become engaged in complexes with beta1-, beta2-, and beta3-integrins. This article will focus on the molecular and functional interactions between the uPAR system and vascular integrins and discuss implications for cardiovascular function.
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Affiliation(s)
- K T Preissner
- Institut für Biochemie, Fachbereich Humanmedizin, Justus-Liebig-Universität, Giessen, Germany
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19
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Chavakis T, May AE, Preissner KT, Kanse SM. Molecular mechanisms of zinc-dependent leukocyte adhesion involving the urokinase receptor and beta2-integrins. Blood 1999; 93:2976-83. [PMID: 10216093] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/12/2023] Open
Abstract
The trace element Zinc (Zn2+) has been implicated as a mediator in host defense, yet the molecular basis for its extracellular functions remains obscure. Here, we demonstrate that Zn2+ can induce the adhesion of myelomonocytic cells to the endothelium, as well as to the provisional matrix proteins vitronectin (VN) and fibrinogen (FBG), which are pivotal steps for the recruitment of leukocytes into inflamed/injured tissue. Physiologic concentrations of Zn2+ increased the urokinase receptor (uPAR)-mediated adhesion of myelomonocytic cells to VN, whereas other divalent cations had smaller effects. Zn2+-induced cell adhesion to VN was abolished by cation chelators such as 1-10-phenanthroline, as well as by plasminogen activator inhibitor-1 (PAI-1) and a monoclonal antibody (MoAb) against uPAR. These characteristics could be recapitulated with a uPAR-transfected cell line emphasizing the specificity of this receptor system for Zn2+-dependent cell adhesion. Like urokinase (uPA), Zn2+ increased the binding of radiolabeled VN to uPAR-expressing cells, as well as the interaction of VN with immobilized uPAR in an isolated system. Moreover, Zn2+ enhanced leukocytic cell adhesion to FBG and endothelial cell monolayers by activating beta2-integrins. Instead of the direct beta2-integrin activation through the divalent cation binding site, Zn2+-induced integrin activation was mediated via uPAR, a crucial regulator of this system. The present study uncovers for the first time Zn2+-mediated cell adhesion mechanisms that may play a crucial role in modulating leukocyte adhesion to vessel wall components.
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Affiliation(s)
- T Chavakis
- Haemostasis Research Unit, Kerckhoff-Klinik, MPI, Bad Nauheim, Medizinische Klinik und Deutsches Herzzentrum, Technische Universität München, Munich, Germany
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20
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Wohn KD, Schmidt T, Kanse SM, Yutzy B, Germer M, Morgenstern E, Preissner KT. The role of plasminogen activator inhibitor-1 as inhibitor of platelet and megakaryoblastic cell adhesion. Br J Haematol 1999; 104:901-8. [PMID: 10192457 DOI: 10.1046/j.1365-2141.1999.01242.x] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
In the present study the ability of plasminogen activator inhibitor type-1 (PAI-1) to interfere with platelet and megakaryoblastic cell adhesion was investigated. Both cell types exhibited integrin-dependent adhesion in a static system, mediated by alphaIIb beta3 on platelets and alpha v-integrins on different megakaryoblastic cell lines, even though they also expressed alphaIIb beta3. In a concentration-dependent manner, active, but not latent or complexed, PAI-1 abrogated cell adhesion onto vitronectin but not onto fibrinogen or other matrix substrata. Urokinase as well as thrombin neutralized the anti-adhesive effect of active PAI-1. The direct binding of vitronectin, but not of other matrix proteins, to integrin alphaIIb beta3 was blocked by active PAI-1 in a purified system. Since activated platelets release active and latent PAI-1 as well as structurally and functionally distinct forms of vitronectin, the described interactions appear to be physiologically significant. Co-distribution of vitronectin and PAI-1 at sites of fibrin polymers within platelet thrombi was demonstrated by transmission electron microscopy, suggesting an extracellular functional relationship of both release products with regard to cell adhesion. Our data emphasize the regulatory role of active PAI-1 in platelet adhesion to provisional matrix proteins as found during wound healing independent of its anti-proteolytic activity. Furthermore, megakaryocyte maturation may depend on the intact vitronectin-integrin adhesion system that is influenced by PAI-1, thereby proposing a regulatory role for the inhibitor in cellular differentiation.
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Affiliation(s)
- K D Wohn
- Haemostasis Research Unit, Max-Planck-Institut, Kerckhoff-Klinik, Bad Nauheim, Germany
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21
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Klouche M, May AE, Hemmes M, Messner M, Kanse SM, Preissner KT, Bhakdi S. Enzymatically modified, nonoxidized LDL induces selective adhesion and transmigration of monocytes and T-lymphocytes through human endothelial cell monolayers. Arterioscler Thromb Vasc Biol 1999; 19:784-93. [PMID: 10073987 DOI: 10.1161/01.atv.19.3.784] [Citation(s) in RCA: 42] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Circulating monocytes and T lymphocytes extravasate through the endothelium at sites of developing atheromatous lesions, where they tend to accumulate and mediate the progression of the disease. We have previously demonstrated the presence of an enzymatically degraded, nonoxidized form of LDL (E-LDL) in early human fatty streaks, which possesses major biological properties of an atherogenic lipoprotein. The effects of E-LDL on human endothelial cells have now been studied with respect to adhesion and transmigration of monocytes and T lymphocytes. E-LDL induced a rapid and dose-dependent selective adhesion of monocytes and T lymphocytes to endothelial cell monolayers within 30 minutes of incubation. Maximal increases in the number of adherent monocytes (8-fold) and of adherent T lymphocytes (4-fold) were observed after treatment with 50 microg/mL E-LDL. E-LDL was more active than oxidized LDL (ox-LDL), whereas native LDL produced only minor adhesive effects. Both E-LDL and ox-LDL enhanced transmigration of monocytes and of T lymphocytes through endothelial monolayers. Again, E-LDL was more potent than ox-LDL, inducing transmigration to a similar extent as N-formyl-Met-Leu-Phe. In endothelial cells, E-LDL stimulated upregulation of intercellular adhesion molecule-1 (ICAM-1), platelet-endothelial cells adhesion molecule-1 (PECAM-1), P-selectin, and E-selectin with distinct kinetics. Analyses with blocking antibodies indicated that ICAM-1 and P-selectin together mediated approximately 70% of cell adhesion, whereas blocking of PECAM-1 had no effect on adhesion but reduced transmigration to less than 50% of controls. E-LDL also upregulated expression of ICAM-1 in human aortic smooth muscle cells, and this correlated with increased adhesion of T lymphocytes. E-LDL is thus able to promote the selective adhesion of monocytes and T lymphocytes to the endothelium, stimulate transmigration of these cells, and foster their retention in the vessel wall by increasing their adherence to smooth muscle cells. These findings underline the potential significance of E-LDL in the pathogenesis of atherosclerosis.
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MESH Headings
- Arteriosclerosis/metabolism
- Arteriosclerosis/pathology
- Cell Adhesion/drug effects
- Cell Adhesion/physiology
- Cell Movement/drug effects
- Cell Movement/physiology
- Cholesterol, LDL/metabolism
- Cholesterol, LDL/pharmacology
- Dose-Response Relationship, Drug
- E-Selectin/analysis
- Endothelium, Vascular/chemistry
- Endothelium, Vascular/cytology
- Endothelium, Vascular/enzymology
- HL-60 Cells
- Humans
- Intercellular Adhesion Molecule-1/analysis
- Kinetics
- Lipoproteins, LDL/pharmacology
- Monocytes/cytology
- Muscle, Smooth, Vascular/chemistry
- Muscle, Smooth, Vascular/cytology
- Muscle, Smooth, Vascular/enzymology
- P-Selectin/analysis
- Platelet Endothelial Cell Adhesion Molecule-1/analysis
- T-Lymphocytes/cytology
- Umbilical Veins/cytology
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Affiliation(s)
- M Klouche
- Institute of Medical Microbiology, Johannes Gutenberg University of Mainz, Germany.
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22
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Abstract
The urokinase receptor (CD87; uPAR) is found in close association with beta 2 integrins on leukocytes. We studied the functional consequence of this association for leukocyte adhesion and migration. In vivo, the beta 2 integrin-dependent recruitment of leukocytes to the inflamed peritoneum of uPAR-deficient mice was significantly reduced as compared with wild-type animals. In vitro, beta 2 integrin-mediated adhesion of leukocytes to endothelium was lost upon removal of uPAR from the leukocyte surface by phosphatidyl-inositol-specific phospholipase C. Leukocyte adhesion was reconstituted when soluble intact uPAR, but not a truncated form lacking the uPA-binding domain, was allowed to reassociate with the cell surface. uPAR ligation with a monoclonal antibody induced adhesion of monocytic cells and neutrophils to vascular endothelium by six- to eightfold, whereas ligation with inactivated uPA significantly reduced cell-to-cell adhesion irrespective of the beta 2 integrin-stimulating pathway. These data indicate that beta 2 integrin-mediated leukocyte-endothelial cell interactions and recruitment to inflamed areas require the presence of uPAR and define a new phenotype for uPAR-deficient mice. Moreover, uPAR ligation differentially modulates leukocyte adhesion to endothelium and provides novel targets for therapeutic strategies in inflammation-related vascular pathologies.
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MESH Headings
- Animals
- Antibodies, Monoclonal/pharmacology
- CD18 Antigens/metabolism
- CD18 Antigens/physiology
- Cell Adhesion/immunology
- Cell Movement/immunology
- Endothelium, Vascular/cytology
- Endothelium, Vascular/immunology
- Female
- Humans
- Leukocytes/enzymology
- Leukocytes/immunology
- Leukocytes/metabolism
- Mice
- Mice, Knockout
- Muscle, Smooth/cytology
- Muscle, Smooth/immunology
- Plasminogen Activators/metabolism
- Receptors, Cell Surface/genetics
- Receptors, Cell Surface/immunology
- Receptors, Cell Surface/physiology
- Receptors, Urokinase Plasminogen Activator
- Tumor Cells, Cultured
- Umbilical Veins
- Urokinase-Type Plasminogen Activator/metabolism
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Affiliation(s)
- A E May
- Haemostasis Research Unit, Max-Planck Institute, Kerckhoff-Klinik, D-61231 Bad Nauheim, Germany
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23
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Germer M, Kanse SM, Kirkegaard T, Kjøller L, Felding-Habermann B, Goodman S, Preissner KT. Kinetic analysis of integrin-dependent cell adhesion on vitronectin--the inhibitory potential of plasminogen activator inhibitor-1 and RGD peptides. Eur J Biochem 1998; 253:669-74. [PMID: 9654064 DOI: 10.1046/j.1432-1327.1998.2530669.x] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Distinct binding interactions between cell-surface receptors and extracellular matrix components are characteristic of multifunctional adhesion proteins such as vitronectin. The close proximity of binding sites for alpha(v)-integrins and plasminogen activator inhibitor-1 (PAI-1) on vitronectin may have consequences for cell adhesion and migration, or for the localized inhibition of plasminogen activators. In this study, the kinetics and reversibility of vitronectin-dependent cell adhesion via alpha(v)-integrins was investigated using RGD peptides and PAI-1 as competitors. Active, but not latent or cleaved PAI-1, and RGD peptides were effective in preventing cell adhesion to vitronectin provided the inhibitor was present at the time of cell seeding. In a concentration-dependent manner urokinase or thrombin abrogated the inhibitory effect of PAI-1. Following cell seeding onto a vitronectin substratum, delayed addition of RGD peptides or active PAI-1 (10-20 min post-seeding) resulted in the loss of their inhibitory potential. These data were supported by experiments in a purified system where delayed addition of active PAI-1 could no longer prevent vitronectin binding to immobilized alpha(v)beta3, while a cyclic RGD peptide gave some moderate inhibition. The apparent stabilization of vitronectin-integrin contacts was observed with immobilized native or multimeric vitronectin but not with the more rigid form of denatured, aggregated multimers. These results demonstrate that the cell adhesive properties of vitronectin depend on its conformational flexibility and can be tightly regulated in a spatio-temporal manner through direct competition of cellular integrins by soluble or matrix-bound factors such as PAI-1.
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Affiliation(s)
- M Germer
- Haemostasis Research Unit, Kerckhoff-Klinik, Max-Planck-Institute, Bad Nauheim, Germany
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24
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Chavakis T, Kanse SM, Yutzy B, Lijnen HR, Preissner KT. Vitronectin concentrates proteolytic activity on the cell surface and extracellular matrix by trapping soluble urokinase receptor-urokinase complexes. Blood 1998; 91:2305-12. [PMID: 9516128] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Urokinase-type-plasminogen activator (uPA) and its receptor are localized in the vessel wall where they are involved in cellular activation and remodelling processes. Besides the cell surface glycolipid (GPI)-anchored urokinase receptor (uPAR), which binds uPA with high affinity, recent evidence points to the existence of soluble uPAR (suPAR), as well. In the present study, the origin, binding mechanism, and cellular effects of suPAR were examined. Under basal conditions human vascular smooth muscle cells (HVSMC), human umbilical vein endothelial cells (HUVEC), and monocytic cells released 0.1 to 2 ng/mL suPAR, which was increased twofold to fivefold after phorbol ester (PMA) stimulation, as measured by a function-dependent enzyme-linked immunosorbent assay (ELISA). suPAR alone did not bind to HVSMC or HUVEC, but reduced cellular uPA binding by 50% to 70%. However, after removal of GPI-uPAR with phosphatidylinositol-specific phospholipase C, suPAR dose-dependently increased uPA binding by fourfold to fivefold. This increase in binding was completely inhibited by vitronectin (VN) and by a monoclonal antibody against VN, but not by other matrix proteins or antibodies. Thus, VN-mediated uPA binding to cells was regulated by the ratio of soluble to surface-associated uPAR. In a uPAR-deficient cell line (LM-TK-), suPAR increased uPA binding up to 10-fold, whereas the truncated receptor lacking the amino-terminal uPA-binding domain was ineffective. The formation of a ternary uPA/suPAR/VN-complex on the cell surface and the free extracellular matrix could be inhibited by a monoclonal antibody against VN, as well as by plasminogen activator inhibitor-1 (PAI-1). Moreover, VN-mediated binding of the uPA/suPAR-complex led to a fivefold increase in plasminogen activator activity. Through this novel pathway, VN concentrates the uPA/suPAR-complex to cell surfaces and extracellular matrix sites, leading to the accumulation of plasminogen activator activity required for cell migration and tissue remodelling processes.
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Affiliation(s)
- T Chavakis
- Max-Planck-Institut, Kerckhoff-Klinik, Bad Nauheim, Germany
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25
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Abstract
Recently, fragments of extracellular proteins, including endostatin, were defined as a novel group of angiogenesis inhibitors. In this study, human plasma equivalent hemofiltrate was used as a source for the purification of high molecular weight peptides (10-20 kDa), and the isolation and identification of circulating human endostatin are described. The purification of this C-terminal fragment of collagen alpha1(XVIII) was guided by MALDI-MS and the exact molecular mass determined by ESI-MS was found to be 18 494 Da. N-terminal sequencing revealed the identity of this putative angiogenesis inhibitor and its close relation to mouse endostatin. The cysteine residues 1-3 and 2-4 in the molecule are linked by disulfide bridges. In vitro biological characterization of the native protein demonstrated no anti-proliferative activity on different endothelial cell types. These data indicate that human endostatin, which is a putative angiogenesis inhibitor, is present in the circulation.
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Affiliation(s)
- L Ständker
- Lower Saxony Institute for Peptide Research (IPF), Hannover, Germany
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26
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Abstract
The interplay between adhesion receptors and proteolytic cascades is crucial for cell proliferation and migration in the (patho-)physiology of vascular function. Disregulated angiogenesis in diabetic retinopathy appears to be associated with the appearance of advanced glycation end products that disturb interactions between capillary cells and extracellular matrix. Vitronectin receptor-type integrins are expressed on angiogenic endothelial cells and contribute to unwanted vascular sprouting in the retinal tissue. In a hypoxia-induced retinal neovascularization model, intervention with low molecular weight integrin antagonist resulted in significant reduction of unwanted angiogenesis indicating that this angiostatic therapy appears to be promising also for late complications in diabetes.
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Affiliation(s)
- K T Preissner
- Haemostasis Research Unit, Kerckhoff Klinik, MPI, Bad Nauheim, Germany
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27
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Kanse SM, Benzakour O, Kanthou C, Kost C, Lijnen HR, Preissner KT. Induction of vascular SMC proliferation by urokinase indicates a novel mechanism of action in vasoproliferative disorders. Arterioscler Thromb Vasc Biol 1997; 17:2848-54. [PMID: 9409265 DOI: 10.1161/01.atv.17.11.2848] [Citation(s) in RCA: 56] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
The urokinase-type plasminogen activator (UPA) and its receptor are expressed in the vasculature and are involved in cell migration and remodeling of the extracellular matrix in the neointima. Vessels with atherosclerosis or neointimal hyperplasia, when compared with normal vessels, contain high UPA activity as well as increased levels of UPA receptor. In this study, we have identified the stimulation of vascular smooth muscle cell proliferation as a novel activity for UPA in the vessel wall. High-molecular-weight-UPA (12-200 nmol/L range) stimulated DNA synthesis and cell proliferation, which was half that induced by fetal calf serum or by platelet-derived growth factor-BB. UPA did not induce growth of endothelial cells, and tissue-type plasminogen activator showed no activity on either cell type. Induction of proliferation required the complete UPA molecule but was independent of the proteolytic activity of UPA, whereas neither the amino-terminal fragment nor the catalytic domain by itself was mitogenic. UPA also stimulated c-fos/c-myc mRNA expression and mitogen-activated protein kinase activity in smooth muscle cells. Blocking monoclonal antibodies against the UPA receptor and the enzymatic removal of receptors were ineffective in inhibiting the mitogenic effect of UPA, suggesting a UPA receptor-independent mechanism. Thus, we provide evidence for a novel function of UPA on vascular smooth muscle cell proliferation that, together with its previously documented involvement in regulating pericellular proteolysis-related events and cell migration, provides additional evidence for a role in the pathogenesis of atherosclerosis/restenosis.
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MESH Headings
- Aorta/cytology
- Calcium-Calmodulin-Dependent Protein Kinases/metabolism
- Cell Division/drug effects
- Cells, Cultured
- DNA Replication/drug effects
- Endothelium, Vascular/drug effects
- Endothelium, Vascular/metabolism
- Gene Expression Regulation/drug effects
- Genes, fos/drug effects
- Genes, myc/drug effects
- Growth Substances/pharmacology
- Humans
- Muscle, Smooth, Vascular/cytology
- Muscle, Smooth, Vascular/drug effects
- Receptors, Cell Surface/physiology
- Receptors, Urokinase Plasminogen Activator
- Saphenous Vein/cytology
- Umbilical Veins/cytology
- Urokinase-Type Plasminogen Activator/pharmacology
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Affiliation(s)
- S M Kanse
- Max-Planck-Institute, Kerckhoff-Klinik, Bad Nauheim, Germany.
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28
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Preissner KT, May AE, Wohn KD, Germer M, Kanse SM. Molecular crosstalk between adhesion receptors and proteolytic cascades in vascular remodelling. Thromb Haemost 1997; 78:88-95. [PMID: 9198134] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
The multifunctionality of adhesion receptor ligands as well as the promiscuous nature of vascular integrins and nonintegrin-dependent adhesive interactions allow ligand-receptor binding of variable strength. The cooperation with pericellular proteolysis cascades is required for vascular remodelling during angiogenesis, atherogenesis or inflammatory processes. In particular, integrin-dependent cell contact, spreading and (trans-)migration can be modulated by ECM-associated PAI-1 and uPA-receptor driven reactions that are intimately linked to the invasive potential of cells. Recently, mechanisms of molecular crosstalk between these receptor systems have been recognized: (a) uPA-receptor may directly interact with beta 1- and beta 2-integrins on circulating blood cells; (b) av beta 3-integrin-directly binds to a matrix metalloproteinase; (c) uPA and PAI-1 balance the high affinity binding of vitronectin to uPA-receptor; (d) vitronectin-dependent cell adhesion and migration involving alpha v-integrins or uPA-receptor are blocked by active PAI-1 independent of its role as protease inhibitor. These results are compatible with vascular injury studies in uPA- and PAI-1 knock-out mice and provide new targets for the treatment of diseases associated with imbalanced vascular remodelling.
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Affiliation(s)
- K T Preissner
- Haemostasis Research Unit, Kerchoff-Klinik, Bad Nauheim, Germany. klaus.t.preissnerkerckhoff.med.uni-giessen.de
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29
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Kjøller L, Kanse SM, Kirkegaard T, Rodenburg KW, Rønne E, Goodman SL, Preissner KT, Ossowski L, Andreasen PA. Plasminogen activator inhibitor-1 represses integrin- and vitronectin-mediated cell migration independently of its function as an inhibitor of plasminogen activation. Exp Cell Res 1997; 232:420-9. [PMID: 9168821 DOI: 10.1006/excr.1997.3540] [Citation(s) in RCA: 182] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Cell migration involves the integrins, their extracellular matrix ligands, and pericellular proteolytic enzyme systems. We have studied the role of plasminogen activator inhibitor-1 (PAI-1) in cell migration, using human amnion WISH cells and human epidermoid carcinoma HEp-2 cells in an assay measuring migration from microcarrier beads and a modified Boyden-chamber assay. Active, but not latent or reactive center-cleaved, PAI-1 inhibited migration. A PAI-1 mutant without ability to inhibit plasminogen activation was as active as wild-type PAI-1 as a migration inhibitor, showing that inhibition of plasminogen activation was not involved. PAI-1 specifically interfered with intergrin- and vitronectin-mediated migration: Migration onto vitronectin-coated but not onto fibronectin-coated surfaces was inhibited by PAI-1, a cyclic RGD peptide inhibited migration, and both cell lines expressed vitronectin-binding alpha v-integrins. In addition, active PAI-1, but not latent or reactive center-cleaved PAI-1, inhibited vitronectin binding to integrins in an in vitro binding assay, without affecting binding of fibronectin. Monoclonal antibodies against the urokinase receptor, another vitronectin binding protein, did not affect cell migration in the beads assay, while some inhibitory effect was observed in the Boyden-chamber assay. We conclude that PAI-1, independently of its role as a proteinase inhibitor, inhibits cell migration by competing for vitronectin binding to integrins, while the interference of PAI-1 with binding of vitronectin to the urokinase receptor may play a secondary role. These data define a novel function for the serpin PAI-1, enabling it to regulate cell migration over vitronectin-rich extracellular matrix in the body.
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Affiliation(s)
- L Kjøller
- Department of Molecular and Structural Biology, University of Arhus, Denmark
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30
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Wohn KD, Kanse SM, Deutsch V, Schmidt T, Eldor A, Preissner KT. The urokinase-receptor (CD87) is expressed in cells of the megakaryoblastic lineage. Thromb Haemost 1997; 77:540-7. [PMID: 9066008] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
Megakaryocytopoiesis is governed in the bone marrow microenvironment by cellular interactions that include various adhesion receptor systems and pericellular proteolysis for proper regulation of cell motility and differentiation. In order to define the role of cell surface molecules required for these processes, we searched for protease receptors on these cells. In an in vitro system utilizing different cell lines of the megakaryoblastic lineage (MEG-01, Dami), low level surface expression of the urokinase (uPA) receptor was noted. Following stimulation with phorbolester (PMA), a 3-6 fold higher expression of uPA receptor over a period of up to 5 days could be observed by fluorescent activated cell-sorting as well as by direct ligand-binding of amino-terminal fragment of uPA or vitronectin. Together with elevated expression of alpha IIb beta 3-integrin (glycoprotein IIb/IIIa complex), double immuno-fluorescence staining of stimulated cells confirmed the increased cell surface localization of uPA receptor. Semi-quantitative RT-PCR, ligand blot analysis and measurement of cell-bound proteolytic activity revealed a differentiation-dependent upregulation of the uPA receptor expression in megakaryoblastic cell lines as in monocytic cells. Due to its glycolipid anchorage, incubation with phosphatidylinositol-specific phospholipase C reduced uPA receptor-mediated ligand binding by about 60%, uPA receptor mRNA was expressed in cultured megakaryocytes derived from bone marrow, whereas no uPA receptor mRNA was detectable in platelets. These results indicate a differentiation-dependent increase in the expression of uPA receptor in megakaryoblastic cells. The characteristics of surface expression and functionality of the receptor on megakaryocytic cells may influence their maturation by regulating cellular communication in the bone marrow micro-environment.
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Affiliation(s)
- K D Wohn
- Haemostasis Research Unit, Kerckhoff-Klinik, MPI, Bad Nauheim, Germany
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31
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Benzakour O, Kanthou C, Kanse SM, Scully MF, Kakkar VV, Cooper DN. Evidence for cultured human vascular smooth muscle cell heterogeneity: isolation of clonal cells and study of their growth characteristics. Thromb Haemost 1996; 75:854-8. [PMID: 8725736] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
The monoclonal theory of atherosclerosis postulates that the initial vascular smooth muscle cell (VSMC) proliferative event involves the expansion of a single cell or a sub-population of cells thus implying differences in the replicative potential of VSMC. Using the technique of limited dilution, VSMC clones derived from animal tissues have been previously isolated and shown to be morphologically heterogeneous. However, the same technique applied to human VSMC (HVSMC) has been unsuccessful, possibly because HVSMC do not grow when plated at very low densities. In this report, the anchorage-independent growth factor-BB (PDGF-BB) and to lesser extent PDGF-AB and basic fibroblast growth factor (bFGF) induced colony formation. This assay provided a tool for the isolation of HVSMC clones. In terms of their growth characteristics and responsiveness to several growth factors, isolated HVSMC clones and the original parental cell population exhibited marked heterogeneity.
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Affiliation(s)
- O Benzakour
- Thrombosis Research Institute, Chelsea, London, UK
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32
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Abstract
We have previously demonstrated that vitronectin (VN), a morphoregulatory protein in the vessel wall, is internalized and translocated to the subendothelial matrix by an integrin-independent mechanism (J. Histochem. Cytochem. 41, 1823-1832, 1993). The cell surface component which mediates the initial contact of VN with endothelial cells is defined here. The specific binding of VN to endothelial cells demonstrated the following properties: a threefold increase after phorbol ester treatment; 85% inhibition by pretreatment of cells with phosphatidylinositol-phospholipase C to release glycolipid-anchored surface proteins; a 90% inhibition by urokinase (u-PA) receptor blocking antibody. u-PA increased VN binding to cells due to an eightfold increase in the affinity of VN for the u-PA receptor. Structure-function studies showed that the amino-terminal fragment of u-PA, devoid of any proteolytic activity, mediated this effect. Active plasminogen activator inhibitor-1 (PAI-1), but not inactivated PAI-1, inhibited VN binding to cells and displaced VN that was prebound to endothelial cell monolayers. Similarly, VN binding to purified (immobilized) u-PA receptor, but not to integrin, was enhanced by u-PA and inhibited by PAI-1. Hence, the binding of soluble VN to endothelial cell surfaces is mediated by the u-PA receptor, and the relative concentrations of u-PA and PAI-1 are able to regulate the strength of this interaction. Endothelial cell adhesion to immobilized VN was found to be integrin-mediated without any involvement of the VN-uPA-receptor system. Hence, the interaction of VN with the u-PA receptor may be involved in the regulation of cellular processes necessary for endothelial cell invasion and migration at VN-rich extracellular matrix sites.
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Affiliation(s)
- S M Kanse
- Haemostasis Research Unit, Kerckhoff-Klinik, Bad Nauheim, Germany
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Kanthou C, Kanse SM, Kakkar VV, Benzakour O. Involvement of pertussis toxin-sensitive and -insensitive G proteins in alpha-thrombin signalling on cultured human vascular smooth muscle cells. Cell Signal 1996; 8:59-66. [PMID: 8777142 DOI: 10.1016/0898-6568(95)02018-7] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
Alpha-thrombin, a key enzyme of the coagulation cascade, is also a potent mitogen for human vascular smooth muscle cells (HVSMC). Here it is demonstrated that the alpha-thrombin-mediated reduction of intracellular cAMP levels is sensitive to pertussis toxin (PTX). cAMP-elevating agents inhibited alpha-thrombin- and serum-induced mitogenesis, thus cAMP confers an anti-mitogenic signal on HVSMC. The PTX-dependent ADP-ribosylation of a 41 kDa Gi alpha protein(s) was significantly inhibited (up to 55%) by thrombin. HVSMC membranes had an intrinsic GTP'ase activity which was significantly increased (up to 36%) by thrombin. PTX treatment did not alter thrombin-induced elevation of GTP'ase activity. Thrombin stimulated phosphatidyl inositol (PI) turnover in a PTX-insensitive manner. This suggested that PTX insensitive G proteins such as Gq are also activated by thrombin. This study on HVSMC provides additional evidence for the involvement of different families of G proteins in thrombin signalling.
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Affiliation(s)
- C Kanthou
- Thrombosis Research Institute, Chelsea, London, UK
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Kanthou C, Kanse SM, Newman P, Kakkar VV, Benzakour O. Variability in the proliferative responsiveness of cultured human vascular smooth muscle cells to alpha-thrombin. Blood Coagul Fibrinolysis 1995; 6:753-60. [PMID: 8825227 DOI: 10.1097/00001721-199512000-00010] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
alpha-Thrombin, a key enzyme of the coagulation cascade, is also a potent mitogen for many cell types. In the present study, the responsiveness to alpha-thrombin of cultured human vascular smooth muscle cells (HVSMC) derived from either vein or normal and atherosclerotic arteries was investigated. All HVSMC populations examined responded mitogenically to alpha-thrombin. However, the extent of this response varied between different cell populations. No significant differences were observed between HVSMC derived from vein versus artery or atherosclerotic versus normal tissues. The responsiveness of a specific HVSMC culture to alpha-thrombin was not affected by cell density and remained constant over several passages. Unlike platelet-derived growth factor BB (PDGF-BB), alpha-thrombin did not exhibit any significant chemotactic effects on HVSMC or induce their anchorage independent growth in semi-solid medium. The hypothesis that the observed variability in HVSMC responsiveness to alpha-thrombin is due to the heterogeneity of cultured HVSMC is raised and discussed.
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Affiliation(s)
- C Kanthou
- Thrombosis Research Institute, Chelsea, London, United Kingdom
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35
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Benzakour O, Kanthou C, Newman P, Kakkar VV, Kanse SM. Long-term chemotaxis studies on adherent cells: effect of platelet-derived growth factor-BB on human vascular smooth muscle cell migration. Anal Biochem 1995; 230:215-23. [PMID: 7503410 DOI: 10.1006/abio.1995.1466] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
Several chemotaxis methods have been developed which allow the study of different aspects of cell migration. The major limitation of such methods is the lack of a sustained chemotactic signal. Long-term chemotaxis phenomena which are known to take place in vivo have remained largely uninvestigated. Ways to maintain sustained chemotactic signals were sought and the used to investigate the long-term chemotactic effect of platelet-derived growth factor BB (PDGF-BB) on human vascular smooth muscle cells (HVSMC). PDGF-BB was adsorbed onto microcarrier beads and then embedded in agar. PDGF-BB diffusion was slow and a high and sustained local concentration was maintained in the agar. When PDGF-BB-loaded beads embedded in agar were placed at the edge of a tissue culture dish with HVSMC plated in the center, preferential movement was observed in the direction of the PDGF-BB source. This method was subsequently used to study directional movement of HVSMC arising from explants. This report demonstrates that PDGF-BB if present in an anisotropic concentration induces directional cell movement from such explants. By allowing the study of the effect of sustained chemotactic signals upon cultured cells or cells arising from explants, this method may provide a suitable model for investigating in vivo chemotaxis phenomena.
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Affiliation(s)
- O Benzakour
- Thrombosis Research Institute, London, United Kingdom
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36
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Hess S, Kanse SM, Kost C, Preissner KT. The versatility of adhesion receptor ligands in haemostasis: morpho-regulatory functions of vitronectin. Thromb Haemost 1995; 74:258-65. [PMID: 8578469] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Affiliation(s)
- S Hess
- Haemostasis Research Unit, Kerckhoff-Klinik, Bad Nauheim, Germany
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37
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Abstract
Endothelin may play a role in atherosclerosis as it causes smooth muscle cell proliferation and its levels are elevated in patients with atherosclerosis. We report that interleukin-1 beta is a potent inducer of endothelin receptor expression in cultured human vascular smooth muscle cells. The effect is dose- and time-dependent and is due to an increase in receptor number. Endothelin receptor mRNA levels are also elevated. Interleukin-1 beta is a major regulator of endothelin release so, together with its effects on endothelin receptors, it may be responsible for a generalized activation of the endothelin system in diseased vessels.
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Affiliation(s)
- P Newman
- Thrombosis Research Institute, London, UK
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38
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Kanse SM, Wijelath E, Kanthou C, Newman P, Kakkar VV. The proliferative responsiveness of human vascular smooth muscle cells to endothelin correlates with endothelin receptor density. J Transl Med 1995; 72:376-82. [PMID: 7898056] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023] Open
Abstract
BACKGROUND Endothelin (ET), a potent vasoconstrictor peptide, is implicated in disorders of intimal hyperplasia such as atherosclerosis and restenosis. Data from animal models and in vitro studies indicate that ET may act at the level of vascular smooth muscle cell proliferation. In this study the effect of ET on human vascular smooth muscle cells (HVSMC) was investigated. EXPERIMENTAL DESIGN The mitogenic effect of ET on 30, early passage, HVSMC lines derived from normal donors and those undergoing aorto-coronary vein bypass grafting (ACVB) operation was examined and characterized. This was correlated with the density of endothelin receptors on these cells as well as with the rate of endothelin secretion. RESULTS There were no clear differences in the mitogenic responsiveness of cells from normal donors and those undergoing ACVB. In 10 HVSMC lines, DNA synthesis was significantly stimulated (30 to 120% stimulation above control, defined as responders), and an insignificant stimulation (< 30% above control) was observed in 20 cell lines (called non-responders); a similar pattern was observed in the cell multiplication assay. In the responder HVSMC lines, the rank order of ET isopeptides in stimulating mitogenesis was ET-1 = ET-2 > ET-3, and the effect was inhibited by the ET antagonist (BQ-123) suggesting that the ET-receptor-A (ETA) subtype was involved in mediating the actions of ET. Measurement of 125I-ET-1 binding to cells indicated there to be a strong correlation between the extent of ET mitogenic effect and receptor binding (N = 30, p = 0.034) but none with the rate of ET secretion. CONCLUSIONS These results suggest that increased levels of ET receptors on HVSMC, as observed in atherosclerotic plaques, may predispose them to ET-stimulated proliferation.
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Affiliation(s)
- S M Kanse
- Thrombosis Research Institute, London, United Kingdom
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39
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Dosso AA, Brooks RA, Beltramo E, Molinatti PA, Kanse SM, Kohner EM, Porta M. A study of the effects of human blood derivatives and individual growth factors on [3H]thymidine uptake in bovine retinal pericytes and endothelial cells. Acta Diabetol 1993; 30:207-13. [PMID: 7514054 DOI: 10.1007/bf00569931] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
Pericytes disappear early, selectively and specifically from retinal capillaries in diabetic microangiopathy, but little is known of their growth and turnover in health and disease. We have studied the effects of human blood derivatives and of a panel of individual growth factors on [3H]thymidine incorporation in bovine retinal pericytes and endothelial cells. Human serum and platelet-rich plasma stimulated incorporation of the nucleotide in a dose-dependent manner in both cell types, and did so more potently than platelet-free plasma. Consistent and significant stimulation of DNA synthesis in pericytes was observed with basic fibroblast growth factor (ED50 = 1.8 x 10(-13) mol/l), acidic fibroblast growth factor (7.4 x 10(-12) mol/l), insulin-like growth factor 1 (8.6 x 10(-10) mol/l), insulin (158 microU/ml) and endothelin-1 (6.1 x 10(-10) mol/l). Transforming growth factor beta 1 inhibited DNA synthesis (ID50 = 3.6 x 10(-10) mol/l) and so did heparin (1.4 x 10(-6) mol/l) and low molecular weight heparin (2.9 x 10(-6) mol/l). Retinal endothelial cells were stimulated by basic fibroblast growth factor (3.2 x 10(-13) mol/l) and acidic fibroblast growth factor (1.3 x 10(-9) mol/l), and inhibited by transforming growth factor beta 1 (1.6 x 10(-12) mol/l). Neither cell type was stimulated by platelet-derived growth factor (A + B chain heterodimer), epidermal growth factor, growth hormone, or nerve growth factor (7S complex). The characteristics and active concentrations of the above growth factors suggest that none is solely responsible for the pericyte mitogenic activity of platelets, serum or plasma.(ABSTRACT TRUNCATED AT 250 WORDS)
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MESH Headings
- Animals
- Arterioles/cytology
- Arterioles/drug effects
- Arterioles/metabolism
- Blood Physiological Phenomena
- Blood Platelets/physiology
- Cattle
- Cells, Cultured
- DNA/biosynthesis
- DNA/drug effects
- Dialysis
- Endothelins/pharmacology
- Endothelium, Vascular/cytology
- Endothelium, Vascular/drug effects
- Endothelium, Vascular/metabolism
- Fibroblast Growth Factor 1/pharmacology
- Fibroblast Growth Factor 2/pharmacology
- Growth Substances/pharmacology
- Heparin/pharmacology
- Humans
- Kinetics
- Muscle, Smooth, Vascular/cytology
- Muscle, Smooth, Vascular/drug effects
- Muscle, Smooth, Vascular/metabolism
- Plasma/physiology
- Retinal Vessels/cytology
- Retinal Vessels/drug effects
- Retinal Vessels/metabolism
- Thymidine/metabolism
- Transforming Growth Factor beta/pharmacology
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Affiliation(s)
- A A Dosso
- Diabetic Retinopathy Unit, Hammersmith Hospital, London, UK
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40
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Propato-Mussafiri R, Kanse SM, Ghatei MA, Bloom SR. Pituitary adenylate cyclase-activating polypeptide releases 7B2, adrenocorticotrophin, growth hormone and prolactin from the mouse and rat clonal pituitary cell lines AtT-20 and GH3. J Endocrinol 1992; 132:107-13. [PMID: 1310712 DOI: 10.1677/joe.0.1320107] [Citation(s) in RCA: 52] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Pituitary adenylate cyclase-activating polypeptide (PACAP) is a neuropeptide originally isolated from ovine hypothalami and so called because of its ability to stimulate pituitary adenylate cyclase activity. Alternative amidation and proteolytic processing of prepro-PACAP gives rise to two bioactive-amidated forms, PACAP-NH2(1-38) (PACAP-38) and PACAP-NH2(1-27) (PACAP-27). 7B2 is a polypeptide of 185 amino acids which is predominantly found in secretory granules and is widely distributed in rat and human tissues. We investigated the ability of the two forms of PACAP to stimulate GH, prolactin and 7B2 release by the rat pituitary clonal cell line GH3, and ACTH and 7B2 by the mouse pituitary clonal cell line AtT-20. PACAP-38 and PACAP-27 stimulated 7B2 and GH/prolactin or ACTH secretion with a similar efficacy over the 2-h incubation period from GH3 and AtT-20 cells respectively. 7B2 secretion was also stimulated by corticotrophin-releasing factor (CRF-41) and vasoactive intestinal polypeptide (VIP) in AtT-20 cells, and thyrotrophin-releasing hormone (TRH) and VIP in GH3 cells. Addition of PACAP to CRF-41 resulted in an additive effect on ACTH secretion and a synergistic effect on 7B2 secretion in AtT-20 cells. No synergism was observed when PACAP was added together with TRH, either on GH and prolactin secretion or on 7B2 release from GH3 cells. PACAP-mediated 7B2 secretion from both cell lines and PACAP-stimulated ACTH release from AtT-20 cells were reduced by 5 mg octapeptide synthetic somatostatin analogue/l (5 mg SMS 201-995/l).
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41
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Jamal H, Jones PM, Byrne J, Suda K, Ghatei MA, Kanse SM, Bloom SR. Peptide contents of neuropeptide Y, vasoactive intestinal polypeptide, and beta-calcitonin gene-related peptide and their messenger ribonucleic acids after dexamethasone treatment in the isolated rat islets of Langerhans. Endocrinology 1991; 129:3372-80. [PMID: 1954911 DOI: 10.1210/endo-129-6-3372] [Citation(s) in RCA: 41] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
A number of neuropeptides including neuropeptide Y (NPY), vasoactive intestinal polypeptide (VIP), and beta-calcitonin gene related peptide (beta-CGRP) are known to influence insulin secretion. In order to investigate whether they might have a local autocrine/paracrine effect within the islets of Langerhans we screened isolated islets by Northern blot analysis and RIA for a number of peptides and found evidence for the presence of messenger RNA (mRNA) encoding NPY, VIP, and beta-CGRP. Dexamethasone treatment for 12 days increased the content of NPY, VIP, and beta-CGRP significantly from 1.3 +/- 0.3 to 19.8 +/- 1.6; 0.25 +/- 0.03 to 0.91 +/- 0.1; 2.2 +/- 0.2 to 4.8 +/- 0.1 fmol/islet respectively, mean +/- SEM (n = 4, P less than 0.05) and remained elevated 24 h after recovery. However when the results were normalized and expressed as a ratio of insulin content only NPY and VIP were significantly raised. Five days post treatment VIP was still significantly elevated compared to controls. mRNA for NPY increased 10-fold and for VIP increased 2 1/2 times after dexamethasone whereas mRNA for beta-CGRP was not significantly different from controls. Neither capsaicin nor 6-hydroxydopamine affected islet content or message of NPY, VIP, and beta-CGRP. Immunoreactive NPY and its mRNA were detected in two cultured beta-cell lines, HIT T-15 and RIN m5F cells whereas VIP and beta-CGRP were undetectable. The local islet synthesis of neuropeptides, which are known to influence islet hormone release pharmacologically, suggests the possibility that they may play a role in intraislet paracrine regulation.
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Affiliation(s)
- H Jamal
- Department of Medicine, Royal Postgraduate Medical School, Hammersmith Hospital, London, United Kingdom
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42
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Abstract
The presence of immunoreactive endothelin (IR-ET) in human saliva and rat parotid gland was investigated by radioimmunoassay. The IR-ET concentration (mean +/- SEM) in saliva taken from normal volunteers was 2.0 +/- 0.2 pmol/l (n = 15). The IR-ET concentration in rat parotid gland was 19.2 +/- 2.2 fmol/g wet weight (n = 10). Fast protein liquid chromatography (FPLC) of human saliva extract revealed 6 peaks; one peak eluting in the void volume, one in a position between ET-1 and -3, and the other four in the positions of synthetic ET-1, -2, -3 and big ET(1-38), respectively. A similar pattern of rat parotid gland extract was noted with FPLC, except that there was no peak after the void volume. Presence of endothelin, a potent growth factor, in saliva and salivary gland points to a role in maintaining the integrity of the oral and gastrointestinal tract mucosa.
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Affiliation(s)
- H C Lam
- Department of Medicine, Royal Postgraduate Medical School, Hammersmith Hospital, London, UK
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43
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Kanse SM, Takahashi K, Warren JB, Ghatei M, Bloom SR. Glucocorticoids induce endothelin release from vascular smooth muscle cells but not endothelial cells. Eur J Pharmacol 1991; 199:99-101. [PMID: 1893930 DOI: 10.1016/0014-2999(91)90641-3] [Citation(s) in RCA: 54] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Vascular smooth muscle cells in culture are capable of secreting endothelin which is a vasoconstrictor and mitogenic peptide. The effect of glucocorticoids on endothelin release from vascular smooth muscle cells of the rat and rabbit aortas was investigated. Micromolar concentrations of dexamethasone and cortisol caused a 2 to 5-fold increase in endothelin release from the two smooth muscle cell types but no such response was observed in endothelial cells of the bovine aorta. Glucocorticoids appear to selectively induce endothelin release from vascular smooth muscle cells and this may be relevant to glucocorticoid-induced hypertension.
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Affiliation(s)
- S M Kanse
- Department of Endocrinology, Royal Postgraduate Medical School, London, U.K
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44
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Kanse SM, Takahashi K, Lam HC, Rees A, Warren JB, Porta M, Molinatti P, Ghatei M, Bloom SR. Cytokine stimulated endothelin release from endothelial cells. Life Sci 1991; 48:1379-84. [PMID: 1901127 DOI: 10.1016/0024-3205(91)90434-d] [Citation(s) in RCA: 65] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Endothelin release from bovine endothelial cells of the aorta, pulmonary artery, and retinal microvessels was measured in response to various cytokines. Transforming growth factor beta (0.05-5 ng/ml) was found to be a potent stimulator (3-4 fold increase) of endothelin secretion in all three cell types. Tumour necrosis factor alpha (0.1-10 ng/ml) and interferon gamma (8-800 U/ml) had a small (1.5-2 fold increase) but significant effect on endothelin secretion from endothelial cells of large vessels but not the retinal microvessels. Interleukin-1 beta, Interleukin-6 and interleukin-8 at various doses did not affect endothelin secretion. These effects were observed at various time points from 6-24 hrs and indicate that of the cytokines tested, only transforming growth factor beta has a potent effect on endothelin release from endothelial cells of different organs.
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Affiliation(s)
- S M Kanse
- Department of Endocrinology, Royal Postgraduate Medical School, London, United Kingdom
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45
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Abstract
Endothelin (ET) production by cultured vascular smooth muscle cells isolated from rat and rabbit aortae was measured by a specific radioimmunoassay. Vascular smooth muscle cells released ET at a rate of 0.6 (range of 0.1-1) fmol/10(5) cells/24 h compared to 45 (range of 10-80) fmol/10(5) cells/h for endothelial cells. ET immunoreactivity was confirmed as ET-1 by fast protein liquid chromatography. Calcitonin gene-related peptide (CGRP) and vasoactive intestinal polypeptide (VIP) suppressed basal release of ET by 24-66% from both rat and rabbit vascular smooth muscle. Forskolin and dibutryl-cAMP similarly suppressed ET release by 33-86%, suggesting that increased intracellular cAMP may account for the mechanism of action of CGRP and VIP. In contrast, CGRP and VIP did not have any effect on ET release from endothelial cells. The characteristics and regulation of ET binding sites on vascular smooth muscle cells were measured using [125I]ET-1 as the radioligand. Pretreatment with CGRP, VIP, forskolin, and dibutryl-cAMP increased the ET receptor density on both smooth muscle cell types. The low level production of ET-1 by vascular smooth muscle cells may have an important autocrine function and may be under regulation of neuropeptides localized to perivascular nerves.
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Affiliation(s)
- S M Kanse
- Department of Endocrinology, Royal Postgraduate Medical School, London, U.K
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46
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Takahashi K, Jones PM, Kanse SM, Lam HC, Spokes RA, Ghatei MA, Bloom SR. Endothelin in the gastrointestinal tract. Presence of endothelinlike immunoreactivity, endothelin-1 messenger RNA, endothelin receptors, and pharmacological effect. Gastroenterology 1990; 99:1660-7. [PMID: 2172072 DOI: 10.1016/0016-5085(90)90472-d] [Citation(s) in RCA: 94] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
The possible production and role of endothelin in the gastrointestinal tract was investigated in rats by radioimmunoassay, Northern-blot hybridization, receptor assay using membrane preparations, and pharmacological study using gut strips. Endothelinlike immunoreactivity was detected in all regions (from stomach to colon) of the rat gastrointestinal tract (13-48 fmol/g wet tissue) including the mucosal layer of the ileum and colon (8.4 +/- 2.0 fmol/g wet tissue and 18.4 +/- 2.1 fmol/g wet tissue, respectively, mean +/- SEM; n = 5). Fast protein liquid chromatographic analysis of the endothelinlike immunoreactivity in jejunum, ileum, colon, and colon mucosa extracts showed peaks in the positions of endothelin-1 and endothelin-3. The presence of endothelin-1 messenger RNA was demonstrated by Northern-blot hybridization in the whole colon and pooled ileal and colonic mucosa, but not in the whole jejunum. Specific binding in the rat gastrointestinal tract was particularly high in the fundus of stomach, jejunum, ileum, and colon. In the ileum, many binding sites were found in the circular and longitudinal muscle layers, but few in the mucosal layer. Endothelin-1 and endothelin-3 caused contraction of rat stomach strips, rat colon, and guinea pig ileum. These findings indicate that endothelin is present in the rat gastrointestinal tract, perhaps produced by both vascular endothelial cells and mucosal epithelial cells, and can cause contraction of gastrointestinal smooth muscle. Thus, endothelin may have a physiological role in the control of gastrointestinal function.
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Affiliation(s)
- K Takahashi
- Department of Medicine, Royal Postgraduate Medical School, Hammersmith Hospital, London, England
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47
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Lam HC, Takahashi K, Ghatei MA, Kanse SM, Polak JM, Bloom SR. Binding sites of a novel neuropeptide pituitary-adenylate-cyclase-activating polypeptide in the rat brain and lung. Eur J Biochem 1990; 193:725-9. [PMID: 2249690 DOI: 10.1111/j.1432-1033.1990.tb19392.x] [Citation(s) in RCA: 118] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Pituitary-adenylate-cyclase-activating polypeptide (PACAP) is a novel 38-amino-acid neuropeptide isolated from ovine hypothalamic tissues based on its activity of stimulating adenylate cyclase of rat pituitary cells. Binding sites for PACAP were studied in rat tissue membranes using a 27-amino-acid N-terminal derivative of PACAP [PACAP(1-27)] labelled with 125I. Particularly high specific binding sites of 125I-PACAP(1-27) were noted in the hypothalamus, brain stem, cerebellum and lung. Specific binding sites are also present in the pituitary gland, but at a lower concentration, and mainly in the anterior lobe. Very low concentration of 125I-PACAP(1-27)-binding sites were found in the colon, aorta and kidney membranes and no binding sites were detected in the pancreas and testis. Maximal binding of 125I-PACAP(1-27) was observed at pH 7.4. Interaction of 125I-PACAP(1-27) with its binding site was rapid, specific and saturable as well as time, pH and temperature dependent. PACAP(1-27) is more potent than PACAP in displacing the binding of 125I-PACAP(1-27) with brain membranes [concentration that inhibits 50% of the binding (IC50) = 7.45 +/- 1.52 nM and 11.45 +/- 3.65 nM, respectively; mean +/- SEM, n = 4] and lung membranes (IC50 = 4.41 +/- 0.87 nM and 10.68 +/- 3.09 nM, respectively). Vasoactive intestinal peptide displaced the binding of 125I-PACAP(1-27) in lung membrane (IC50 = 16.88 +/- 5.14 nM) but not in brain membranes. The equilibrium binding of 125I-PACAP(1-27) at 4 degrees C was characterized by a single class of binding site for the brain membrane with a dissociation constant (Kd) of 2.46 +/- 0.53 nM and a maximal binding capacity (Bmax) of 8.44 +/- 3.13 pmol/mg protein, but there were two classes of binding site for lung membranes with Kd of 1.02 +/- 0.51 nM and 5.19 +/- 0.99 nM, and Bmax of 2.84 +/- 0.72 pmol/mg protein and 9.13 +/- 1.89 pmol/mg protein, respectively. These findings suggest that subtypes of PACAP-binding sites exist and PACAP may have a physiological role in the hypothalamus/pituitary axis as well as in other regions of the brain and lung.
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Affiliation(s)
- H C Lam
- Department of Medicine, Royal Postgraduate Medical School, Hammersmith Hospital, London, England
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48
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Calvo JJ, Gonzalez R, De Carvalho LF, Takahashi K, Kanse SM, Hart GR, Ghatei MA, Bloom SR. Release of substance P from rat hypothalamus and pituitary by endothelin. Endocrinology 1990; 126:2288-95. [PMID: 1691695 DOI: 10.1210/endo-126-5-2288] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Endothelin-1 is a 21 amino acid peptide originally isolated from porcine aortic endothelium and has recently been localized within the central nervous system. We have administered endothelin-1 in a dynamic perfusion system in order to study its possible effects on the rat hypothalamus and anterior pituitary. Tissue (hypothalami or quartered pituitaries) was placed into plastic chambers and was perfused with oxygenated Krebs-bicarbonate solution. After an interval to establish stable basal peptide release, endothelin-1 was administered at two doses (0.1 and 1 microM) and the release of substance P, vasoactive intestinal peptide, 7B2, and somatostatin was measured, the last being detectable only in hypothalamic perfusates. Both concentrations of endothelin-1 led to a significant increase (P less than 0.01) in the release of substance P from the hypothalamus and pituitary, but not of vasoactive intestinal peptide, 7B2, or somatostatin. Thus after the 0.1 microM and 1 microM endothelin-1 perfusion substance P release from the hypothalamus increased by 125 +/- 5% and 215 +/- 15% (mean +/- SEM) of basal and from the pituitary by 168 +/- 8% and 276 +/- 15% (mean +/- SEM). No change occurred in the output of ACTH or other pituitary hormones. The release of substance P from hypothalamus or pituitary after stimulation with endothelin-1 was not blocked when a calcium free medium was used. Endothelin-1 binding sites were identified on rat pituitary cell membranes. These findings suggest the possibility that endothelin may act as a paracrine substance, neurotransmitter, or neuromodulator in the hypothalamo-pituitary axis.
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Affiliation(s)
- J J Calvo
- Department of Medicine, Royal Postgraduate Medical School, Hammersmith Hospital, London, United Kingdom
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Takahashi K, Brooks RA, Kanse SM, Ghatei MA, Kohner EM, Bloom SR. Production of endothelin 1 by cultured bovine retinal endothelial cells and presence of endothelin receptors on associated pericytes. Diabetes 1989; 38:1200-2. [PMID: 2548910 DOI: 10.2337/diab.38.9.1200] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Endothelinlike immunoreactivity was detected by radioimmunoassay in medium conditioned by cultured endothelial cells obtained from bovine retinal microvessels (9.2 +/- 6.5 pM, n = 4). Sephadex G-25 column chromatography and fast-protein liquid chromatography revealed that most of the endothelinlike immunoreactivity was eluted in an identical position to synthetic endothelin 1. Retinal capillary pericyte-conditioned medium contained 2.9 pM endothelinlike immunoreactivity. In contrast to endothelial cells, retinal pericytes were found to bind endothelin. The dissociation constant and binding capacity were 0.14 nM and 1.5 x 10(5) sites/cell (n = 3), respectively. These findings suggest that endothelin produced by the retinal endothelial cells binds to the pericytes, adding support to the suggestion that pericytes in the retina may have a musclelike function.
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Affiliation(s)
- K Takahashi
- Department of Medicine, Royal Postgraduate Medical School, Hammersmith Hospital, London, United Kingdom
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Abstract
High-affinity binding sites for endothelin were identified on porcine aortic and rat lung membranes. Interaction of 125I-labelled endothelin with its binding site was specific, saturable, time- and temperature-dependent but dissociation of receptor-bound ligand was minimal. Maximal binding was observed at pH 7.0 in porcine aorta and at pH 3.1 in the rat lung. Treatment of membranes with trypsin destroyed the binding site in both tissues. Porcine endothelin showed a higher affinity for receptors in both tissues compared to rat endothelin. Vasoactive peptides and Ca2+ channel antagonists did not interact with this site suggesting high specificity of binding. Analysis of saturation binding showed that the number of binding sites was 1250 +/- 104 and 1650 +/- 170 fmol/mg protein and the affinity of binding sites was 0.47 +/- 0.15 and 0.16 +/- 0.07 nM in the aorta and the lungs respectively (n = 5). Presence of protease inhibitors did not alter binding suggesting that the label was stable under the incubation conditions. This was further confirmed by HPLC. Removal of the endothelium from the aorta did not change the binding characteristics of this tissue. Ca2+ and Mg2+ ions caused an increase in binding by increasing the affinity. Binding was completely abolished in the presence of Triton and dithiothreitol. The binding sites identified in this study may be responsible for the actions of endothelin in the aorta and the lung.
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Affiliation(s)
- S M Kanse
- Department of Medicine, Royal Postgraduate Medical School, London, England
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