title: Adrenomedullin/cyclic AMP pathway induces Notch activation and differentiation of arterial endothelial cells from vascular progenitors.
abstract: OBJECTIVE
  The acquisition of arterial or venous identity is highlighted in vascular development. Previously, we have reported an embryonic stem (ES) cell differentiation system that exhibits early vascular development using vascular endothelial growth factor (VEGF) receptor-2 (VEGFR2)-positive cells as common vascular progenitors. In this study, we constructively induced differentiation of arterial and venous endothelial cells (ECs) in vitro to elucidate molecular mechanisms of arterial-venous specification.
  
  
  RESULTS
  ECs were induced from VEGFR2+ progenitor cells with various conditions. VEGF was essential to induce ECs. Addition of 8bromo-cAMP or adrenomedullin (AM), an endogenous ligand-elevating cAMP, enhanced VEGF-induced EC differentiation. Whereas VEGF alone mainly induced venous ECs, 8bromo-cAMP (or AM) with VEGF supported substantial induction of arterial ECs. Stimulation of cAMP pathway induced Notch signal activation in ECs. The arterializing effect of VEGF and cAMP was abolished in recombination recognition sequence binding protein at the Jkappa site deficient ES cells lacking Notch signal activation or in ES cells treated with gamma-secretase inhibitor. Nevertheless, forced Notch activation by the constitutively active Notch1 alone did not induce arterial ECs.
  
  
  CONCLUSIONS
  Adrenomedullin/cAMP is a novel signaling pathway to activate Notch signaling in differentiating ECs. Coordinated signaling of VEGF, Notch, and cAMP is required to induce arterial ECs from vascular progenitors.
authors.affiliation: Laboratory of Stem Cell Differentiation, Stem Cell Research Center, Institute for Frontier Medical Sciences, Kyoto University, 53 Shogoin Kawahara-cho, Sakyo-ku, Kyoto 606-8507 Japan.
authors.forename: Takami
authors.initials: T
authors.lastname: Yurugi-Kobayashi
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Itoh
authors.forename: Timm
authors.initials: T
authors.lastname: Schroeder
authors.forename: Akiko
authors.initials: A
authors.lastname: Nakano
authors.forename: Genta
authors.initials: G
authors.lastname: Narazaki
authors.forename: Fumiyo
authors.initials: F
authors.lastname: Kita
authors.forename: Kentoku
authors.initials: K
authors.lastname: Yanagi
authors.forename: Mina
authors.initials: M
authors.lastname: Hiraoka-Kanie
authors.forename: Emi
authors.initials: E
authors.lastname: Inoue
authors.forename: Toshiaki
authors.initials: T
authors.lastname: Ara
authors.forename: Takashi
authors.initials: T
authors.lastname: Nagasawa
authors.forename: Ursula
authors.initials: U
authors.lastname: Just
authors.forename: Kazuwa
authors.initials: K
authors.lastname: Nakao
authors.forename: Shin-ichi
authors.initials: S
authors.lastname: Nishikawa
authors.forename: Jun K
authors.initials: JK
authors.lastname: Yamashita
mesh_terms: D015124:8-Bromo Cyclic Adenosine Monophosphate / Q000494:pharmacology; D053607:Adrenomedullin; D000818:Animals; D001158:Arteries / Q000166:cytology*; D002454:Cell Differentiation / Q000187:drug effects / Q000502:physiology*; D002460:Cell Line; D000242:Cyclic AMP / Q000378:metabolism*; D004357:Drug Synergism; D042783:Endothelial Cells / Q000166:cytology*; D051379:Mice; D010455:Peptides / Q000378:metabolism* / Q000494:pharmacology; D051880:Receptors, Notch / Q000378:metabolism*; D015398:Signal Transduction / Q000502:physiology; D013234:Stem Cells / Q000166:cytology*; D042461:Vascular Endothelial Growth Factor A / Q000494:pharmacology; D014680:Veins / Q000166:cytology
chemical_list: D010455:Peptides; D051880:Receptors, Notch; D042461:Vascular Endothelial Growth Factor A; D053607:Adrenomedullin; D015124:8-Bromo Cyclic Adenosine Monophosphate; D000242:Cyclic AMP