title: Microparticles harboring Sonic Hedgehog promote angiogenesis through the upregulation of adhesion proteins and proangiogenic factors.
abstract: Microparticles (MPs) are small fragments generated from the plasma membrane after cell stimulation or apoptosis. We have recently shown that MPs harboring the morphogen Sonic Hedgehog (MPs(Shh+)) correct endothelial injury by release of nitric oxide from endothelial cells [Agouni, Mostefai, Porro, Carusio, Favre, Richard, Henrion, Martínez and Andriantsitohaina (2007) FASEB J., 21, 2735-2741]. Here, we show that MPs(Shh+) induce the formation of capillary-like structures in an in vitro model using human endothelial cells, although they inhibited cell migration. Besides, MPs(Shh+) regulate cell proliferation. Both cell adhesion and expression of proteins involved in this process such as Rho A and phosphorylation of focal-activated kinase were increased by MPs(Shh+), via a Rho-associated coiled-coil-containing protein kinase inhibitor-sensitive pathway. We demonstrate that MPs(Shh+) increase messenger RNA and protein levels of proangiogenic factors as measured by quantitative reverse transcription-polymerase chain reaction and western blot. In spite of vascular endothelial growth factor expression, conditioned media from endothelial cells treated avec MPs(Shh+) reduces angiogenesis. Interestingly, the effects induced by MPs(Shh+) on the formation of capillary-like structures, expression of adhesion molecules and proangiogenic factors were reversed after silencing of the Shh receptor, using small interfering RNA or when Sonic Hedgehog (Shh) signaling was pharmacologically inhibited with cyclopamine. Taken together, we show that Shh carried by MPs(Shh+) regulate angiogenesis probably through both a direct and an indirect mechanisms, and we propose that MPs harboring Shh may contribute to the generation of a vascular network in pathologies associated with tumor growth.
authors.affiliation: Biologie Neuro-Vasculaire Intégrée, Centre National de la Recherche Scientifique, UMR 6214, Institut National de la Santé et de la Recherche Médicale, U771, Faculté de Médecine, Rue Haute de Reculée, Université d'Angers, F-49045 Angers, France.
authors.forename: Raffaella
authors.initials: R
authors.lastname: Soleti
authors.forename: Tarek
authors.initials: T
authors.lastname: Benameur
authors.forename: Chiara
authors.initials: C
authors.lastname: Porro
authors.forename: Maria Antonietta
authors.initials: MA
authors.lastname: Panaro
authors.forename: Ramaroson
authors.initials: R
authors.lastname: Andriantsitohaina
authors.forename: Maria Carmen
authors.initials: MC
authors.lastname: Martínez
mesh_terms: D043925:Angiogenesis Inducing Agents / Q000378:metabolism*; D002448:Cell Adhesion; D015815:Cell Adhesion Molecules / Q000378:metabolism*; D002465:Cell Movement; D049109:Cell Proliferation; D055252:Cell-Derived Microparticles / Q000502:physiology*; D002478:Cells, Cultured; D004730:Endothelium, Vascular / Q000166:cytology / Q000378:metabolism*; D053823:Hedgehog Proteins / Q000235:genetics / Q000378:metabolism*; D006801:Humans; D009389:Neovascularization, Pathologic / Q000378:metabolism*; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D034741:RNA, Small Interfering / Q000494:pharmacology; D015854:Up-Regulation; D042461:Vascular Endothelial Growth Factor A / Q000235:genetics / Q000378:metabolism; D014704:Veratrum Alkaloids / Q000494:pharmacology; D020742:rhoA GTP-Binding Protein / Q000235:genetics / Q000378:metabolism
chemical_list: D043925:Angiogenesis Inducing Agents; D015815:Cell Adhesion Molecules; D053823:Hedgehog Proteins; D012333:RNA, Messenger; D034741:RNA, Small Interfering; C509239:SHH protein, human; C467484:VEGFA protein, human; D042461:Vascular Endothelial Growth Factor A; D014704:Veratrum Alkaloids; D020742:rhoA GTP-Binding Protein; C000541:cyclopamine