title: E-Prostanoid 3 Receptor Mediates Sprouting Angiogenesis Through Suppression of the Protein Kinase A/β-Catenin/Notch Pathway.
abstract: Angiogenesis is a hallmark of embryonic development and various ischemic and inflammatory diseases. Prostaglandin E2 receptor subtype 3 (EP3) plays an important role in pathophysiologic angiogenesis; however, the precise mechanisms remain unknown. Here, we investigated the role of EP3 in zebra fish embryo and mouse retina angiogenesis and evaluated the underlying mechanisms.
  
  
  
  The EP3 receptor was highly expressed in the vasculature in both zebra fish embryos and murine fetal retinas. Pharmacological inhibition or genetic deletion of EP3 significantly reduced vasculature formation in zebra fish embryos and mouse retinas. Further characterization revealed reduced filopodia extension of tip cells in embryonic retinas in EP3-deficient mice. EP3 deletion activated Notch activity by upregulation of delta-like ligand 4 expression in endothelial cells (ECs). Inhibition of Notch signaling rescued the angiogenic defects in EP3-deficient mouse retinas. Moreover, EP3 deficiency led to a significant increase in β-catenin phosphorylation at Ser675 and nuclear accumulation of β-catenin in ECs. Knockdown or inhibition of β-catenin restored the impaired sprouting angiogenesis resulting from EP3 deficiency in ECs. The EP3 receptor depressed protein kinase A activity in ECs by coupling to Gαi. Inhibition of protein kinase A activity significantly reduced Ser675 phosphorylation and nuclear translocation of β-catenin, abolished the increased delta-like ligand 4 expression, and subsequently restored the impaired angiogenic capacity of EP3-deficient ECs both in vitro and in vivo.
  
  
  
  Activation of the EP3 receptor facilitates sprouting angiogenesis through protein kinase A-dependent Notch signaling, suggesting that EP3 and its downstream pathways maybe potential therapeutic targets in the treatment of ischemic diseases.
authors.affiliation: From the Department of Pharmacology, School of Basic Medical Sciences, Tianjin Medical University, Tianjin, China (D.C., J.Z., Y.S., Y.Y.); and Key Laboratory of Food Safety Research, CAS Center for Excellence in Molecular Cell Science, Institute for Nutritional Sciences, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, University of Chinese Academy of Sciences, Shanghai, China (D.C., J.T., Q.W., K.W., Y.Y.).
authors.forename: Di
authors.initials: D
authors.lastname: Chen
authors.affiliation: From the Department of Pharmacology, School of Basic Medical Sciences, Tianjin Medical University, Tianjin, China (D.C., J.Z., Y.S., Y.Y.); and Key Laboratory of Food Safety Research, CAS Center for Excellence in Molecular Cell Science, Institute for Nutritional Sciences, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, University of Chinese Academy of Sciences, Shanghai, China (D.C., J.T., Q.W., K.W., Y.Y.).
authors.forename: Juan
authors.initials: J
authors.lastname: Tang
authors.affiliation: From the Department of Pharmacology, School of Basic Medical Sciences, Tianjin Medical University, Tianjin, China (D.C., J.Z., Y.S., Y.Y.); and Key Laboratory of Food Safety Research, CAS Center for Excellence in Molecular Cell Science, Institute for Nutritional Sciences, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, University of Chinese Academy of Sciences, Shanghai, China (D.C., J.T., Q.W., K.W., Y.Y.).
authors.forename: Qiangyou
authors.initials: Q
authors.lastname: Wan
authors.affiliation: From the Department of Pharmacology, School of Basic Medical Sciences, Tianjin Medical University, Tianjin, China (D.C., J.Z., Y.S., Y.Y.); and Key Laboratory of Food Safety Research, CAS Center for Excellence in Molecular Cell Science, Institute for Nutritional Sciences, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, University of Chinese Academy of Sciences, Shanghai, China (D.C., J.T., Q.W., K.W., Y.Y.).
authors.forename: Jian
authors.initials: J
authors.lastname: Zhang
authors.affiliation: From the Department of Pharmacology, School of Basic Medical Sciences, Tianjin Medical University, Tianjin, China (D.C., J.Z., Y.S., Y.Y.); and Key Laboratory of Food Safety Research, CAS Center for Excellence in Molecular Cell Science, Institute for Nutritional Sciences, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, University of Chinese Academy of Sciences, Shanghai, China (D.C., J.T., Q.W., K.W., Y.Y.).
authors.forename: Kai
authors.initials: K
authors.lastname: Wang
authors.affiliation: From the Department of Pharmacology, School of Basic Medical Sciences, Tianjin Medical University, Tianjin, China (D.C., J.Z., Y.S., Y.Y.); and Key Laboratory of Food Safety Research, CAS Center for Excellence in Molecular Cell Science, Institute for Nutritional Sciences, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, University of Chinese Academy of Sciences, Shanghai, China (D.C., J.T., Q.W., K.W., Y.Y.). yuying@tmu.edu.cn yujun_shen@yahoo.com.
authors.forename: Yujun
authors.initials: Y
authors.lastname: Shen
authors.affiliation: From the Department of Pharmacology, School of Basic Medical Sciences, Tianjin Medical University, Tianjin, China (D.C., J.Z., Y.S., Y.Y.); and Key Laboratory of Food Safety Research, CAS Center for Excellence in Molecular Cell Science, Institute for Nutritional Sciences, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, University of Chinese Academy of Sciences, Shanghai, China (D.C., J.T., Q.W., K.W., Y.Y.). yuying@tmu.edu.cn yujun_shen@yahoo.com.
authors.forename: Ying
authors.initials: Y
authors.lastname: Yu
mesh_terms: D048868:Adaptor Proteins, Signal Transducing; D000818:Animals; D002135:Calcium-Binding Proteins; D002478:Cells, Cultured; D017868:Cyclic AMP-Dependent Protein Kinases / Q000235:genetics / Q000378:metabolism*; D015232:Dinoprostone / Q000378:metabolism; D004195:Disease Models, Animal; D042783:Endothelial Cells / Q000378:metabolism*; D018507:Gene Expression Regulation, Developmental; D006614:Hindlimb; D047908:Intracellular Signaling Peptides and Proteins / Q000378:metabolism; D007511:Ischemia / Q000201:enzymology / Q000235:genetics / Q000503:physiopathology; D008565:Membrane Proteins / Q000378:metabolism; D018345:Mice, Knockout; D018482:Muscle, Skeletal / Q000098:blood supply; D018919:Neovascularization, Physiologic; D010766:Phosphorylation; D034622:RNA Interference; D051880:Receptors, Notch / Q000378:metabolism*; D058308:Receptors, Prostaglandin E, EP3 Subtype / Q000172:deficiency / Q000235:genetics / Q000378:metabolism*; D015861:Retinal Neovascularization; D012171:Retinal Vessels / Q000196:embryology / Q000378:metabolism*; D015398:Signal Transduction; D014162:Transfection; D015027:Zebrafish / Q000196:embryology / Q000235:genetics / Q000378:metabolism*; D029961:Zebrafish Proteins / Q000172:deficiency / Q000235:genetics / Q000378:metabolism*; D051176:beta Catenin / Q000235:genetics / Q000378:metabolism*
chemical_list: D048868:Adaptor Proteins, Signal Transducing; C495267:CTNNB1 protein, mouse; D002135:Calcium-Binding Proteins; C519665:DLL4 protein, mouse; C000620723:E-prostanoid 3 receptor, zebrafish; D047908:Intracellular Signaling Peptides and Proteins; D008565:Membrane Proteins; C545648:Ptger3 protein, mouse; D051880:Receptors, Notch; D058308:Receptors, Prostaglandin E, EP3 Subtype; D029961:Zebrafish Proteins; D051176:beta Catenin; D017868:Cyclic AMP-Dependent Protein Kinases; D015232:Dinoprostone
keywords: E-prostanoid receptor subtype 3; angiogenesis; delta-like ligand 4/Notch signaling; endothelial cell; tip cell