title: Expression of ADAMTS1 in endothelial cells is induced by shear stress and suppressed in sprouting capillaries.
abstract: ADAMTS1 inhibits capillary sprouting, and since capillary sprouts do not experience the shear stress caused by blood flow, this study undertook to clarify the relationship between shear stress and ADAMTS1. It was found that endothelial cells exposed to shear stress displayed a strong upregulation of ADAMTS1, dependent upon both the magnitude and duration of their exposure. Investigation of the underlying pathways demonstrated involvement of phospholipase C, phosphoinositide 3-kinase, and nitric oxide. Forkhead box protein O1 was identified as a likely inhibitor of the system, as its knockdown was followed by a slight increase in ADAMTS1 expression. In silico prediction displayed a transcriptional binding site for Forkhead box protein O1 in the promotor region of the ADAMTS1 gene, as well as sites for nuclear factor 1, SP1, and AP-1. The anti-angiogenic effects of ADAMTS1 were attributed to its cleavage of thrombospondin 1 into a 70-kDa fragment, and a significant enhancement of this fragment was indeed demonstrated by immunoblotting shear stress-treated cells. Accordingly, scratch wound closure displayed a slowdown in conditioned medium from shear stress-treated endothelial cells, an effect that could be completely blocked by a knockdown of thrombospondin 1 and partially blocked by a knockdown of ADAMTS1. Non-perfused capillary sprouts in rat mesenteries stained negative for ADAMTS1, while vessels in the microcirculation that had already experienced blood flow yielded the opposite results. The shear stress-dependent expression of ADAMTS1 in vitro was therefore also demonstrated in vivo and thereby confirmed as a mechanism connecting blood flow with the regulation of angiogenesis.
authors.affiliation: Shear Stress and Vascular Biology Research Group, Institute of Physiology, Charité-Universitätsmedizin Berlin, Berlin, Germany.
authors.forename: Margret
authors.initials: M
authors.lastname: Hohberg
authors.forename: Judith
authors.initials: J
authors.lastname: Knöchel
authors.forename: Christian J
authors.initials: CJ
authors.lastname: Hoffmann
authors.forename: Sven
authors.initials: S
authors.lastname: Chlench
authors.forename: Wulf
authors.initials: W
authors.lastname: Wunderlich
authors.forename: Alexander
authors.initials: A
authors.lastname: Alter
authors.forename: Julian
authors.initials: J
authors.lastname: Maroski
authors.forename: Bernd J
authors.initials: BJ
authors.lastname: Vorderwülbecke
authors.forename: Luis
authors.initials: L
authors.lastname: Da Silva-Azevedo
authors.forename: Rose
authors.initials: R
authors.lastname: Knudsen
authors.forename: Robert
authors.initials: R
authors.lastname: Lehmann
authors.forename: Katarzyna
authors.initials: K
authors.lastname: Fiedorowicz
authors.forename: Mauro
authors.initials: M
authors.lastname: Bongrazio
authors.forename: Bianca
authors.initials: B
authors.lastname: Nitsche
authors.forename: Michael
authors.initials: M
authors.lastname: Hoepfner
authors.forename: Beata
authors.initials: B
authors.lastname: Styp-Rekowska
authors.forename: Axel R
authors.initials: AR
authors.lastname: Pries
authors.forename: Andreas
authors.initials: A
authors.lastname: Zakrzewicz
mesh_terms: D051722:ADAM Proteins / Q000235:genetics / Q000378:metabolism*; D000071097:ADAMTS1 Protein; D000818:Animals; D002196:Capillaries / Q000502:physiology* / Q000648:ultrastructure; D002460:Cell Line; D042783:Endothelial Cells / Q000166:cytology / Q000187:drug effects / Q000378:metabolism*; D004791:Enzyme Inhibitors / Q000494:pharmacology; D000071161:Forkhead Box Protein O1; D051858:Forkhead Transcription Factors / Q000235:genetics / Q000378:metabolism; D006801:Humans; D018919:Neovascularization, Physiologic; D009569:Nitric Oxide / Q000378:metabolism; D010100:Oxygen / Q000378:metabolism; D019869:Phosphatidylinositol 3-Kinases / Q000235:genetics / Q000378:metabolism; D011401:Promoter Regions, Genetic; D051381:Rats; D017207:Rats, Sprague-Dawley; D033081:Shear Strength; D013314:Stress, Mechanical; D019700:Thrombospondin 1 / Q000235:genetics / Q000378:metabolism; D010738:Type C Phospholipases / Q000235:genetics / Q000378:metabolism
chemical_list: D004791:Enzyme Inhibitors; C085126:FOXO1 protein, human; D000071161:Forkhead Box Protein O1; D051858:Forkhead Transcription Factors; D019700:Thrombospondin 1; D009569:Nitric Oxide; D019869:Phosphatidylinositol 3-Kinases; D010738:Type C Phospholipases; D051722:ADAM Proteins; D000071097:ADAMTS1 Protein; C103859:ADAMTS1 protein, human; C486324:Adamts1 protein, rat; D010100:Oxygen