title: ADAM10 and ADAM17 have opposite roles during sprouting angiogenesis.
abstract: During angiogenesis, endothelial tip cells start sprouting and express delta-like 4 (DLL4) downstream of vascular endothelial growth factor (VEGF). DLL4 subsequently activates Notch in the adjacent stalk cells suppressing sprouting. VEGF also activates A disintegrin and metalloproteases (ADAMs) that induce Notch ectodomain shedding. Although two major ADAMs, i.e. ADAM10 and ADAM17, have been implicated in Notch-signalling activation, their apparent different roles in angiogenesis have not been fully understood yet. The objective of this study was to determine the roles of ADAM10 and ADAM17 activity in angiogenesis. In mouse retinas, ADAM10 or γ-secretase inhibition induced vascular sprouting and density in vivo, whereas attenuation of both ADAM10 and ADAM17 activity produced the opposite phenotype. Retinal blood vessel analysis in ADAM17 hypomorphic mice confirmed the requirement for ADAM17 activity in angiogenesis. However, ADAM17 inhibition did not phenocopy blood vessel increase by Notch blockage. These observations suggest that ADAM17 regulates other fundamental players during angiogenesis besides Notch, which were not affected by ADAM10. By means of an angiogenesis proteome assay, we found that ADAM17 inhibition induced the expression of a naturally occurring inhibitor of angiogenesis Thrombospondin 1 (TSP1), whereas ADAM10 inhibition did not. Accordingly, ADAM17 overexpression downregulated TSP1 expression, and the TSP1 inhibitor LSKL rescued angiogenesis in the tube formation assay downstream of VEGF in the presence of ADAM17 inhibition. Finally, genetic and pharmacological ADAM17 blockade resulted in increased TSP1 expression in mouse retina. Altogether, our results show that ADAM10 and ADAM17 have opposite effects on sprouting angiogenesis that may be unrelated to Notch signalling and involves differentially expressed anti-angiogenic proteins such as TSP1.
authors.affiliation: Department of Physiology, CARIM, Maastricht University, Universiteitssingel 50, 6229 ER, Maastricht, The Netherlands.
authors.forename: V
authors.initials: V
authors.lastname: Caolo
authors.forename: G
authors.initials: G
authors.lastname: Swennen
authors.forename: A
authors.initials: A
authors.lastname: Chalaris
authors.forename: A
authors.initials: A
authors.lastname: Wagenaar
authors.forename: S
authors.initials: S
authors.lastname: Verbruggen
authors.forename: S
authors.initials: S
authors.lastname: Rose-John
authors.forename: D G M
authors.initials: DG
authors.lastname: Molin
authors.forename: M
authors.initials: M
authors.lastname: Vooijs
authors.forename: M J
authors.initials: MJ
authors.lastname: Post
mesh_terms: D051722:ADAM Proteins / Q000378:metabolism*; D000072197:ADAM10 Protein; D000072198:ADAM17 Protein; D048868:Adaptor Proteins, Signal Transducing; D053829:Amyloid Precursor Protein Secretases / Q000378:metabolism*; D000704:Analysis of Variance; D000818:Animals; D015153:Blotting, Western; D002135:Calcium-Binding Proteins; D003094:Collagen; D017931:DNA Primers; D004338:Drug Combinations; D005786:Gene Expression Regulation / Q000502:physiology*; D007150:Immunohistochemistry; D047908:Intracellular Signaling Peptides and Proteins / Q000378:metabolism; D007797:Laminin; D008565:Membrane Proteins / Q000378:metabolism*; D051379:Mice; D018919:Neovascularization, Physiologic / Q000502:physiology*; D011509:Proteoglycans; D051880:Receptors, Notch / Q000378:metabolism; D012160:Retina / Q000378:metabolism / Q000502:physiology*; D020133:Reverse Transcriptase Polymerase Chain Reaction; D015398:Signal Transduction / Q000502:physiology*; D019700:Thrombospondin 1 / Q000378:metabolism
chemical_list: D048868:Adaptor Proteins, Signal Transducing; D002135:Calcium-Binding Proteins; C519665:DLL4 protein, mouse; D017931:DNA Primers; D004338:Drug Combinations; D047908:Intracellular Signaling Peptides and Proteins; D007797:Laminin; D008565:Membrane Proteins; D011509:Proteoglycans; D051880:Receptors, Notch; D019700:Thrombospondin 1; C059485:matrigel; D003094:Collagen; D053829:Amyloid Precursor Protein Secretases; D051722:ADAM Proteins; D000072197:ADAM10 Protein; C491234:Adam10 protein, mouse; D000072198:ADAM17 Protein; C000606463:Adam17 protein, mouse