Expression of ADAMTS1 in endothelial cells is induced by shear stress and suppressed in sprouting capillaries.
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.
Hohberg
Margret
M
Shear Stress and Vascular Biology Research Group, Institute of Physiology, Charité-Universitätsmedizin Berlin, Berlin, Germany.
Knöchel
Judith
J
Hoffmann
Christian J
CJ
Chlench
Sven
S
Wunderlich
Wulf
W
Alter
Alexander
A
Maroski
Julian
J
Vorderwülbecke
Bernd J
BJ
Da Silva-Azevedo
Luis
L
Knudsen
Rose
R
Lehmann
Robert
R
Fiedorowicz
Katarzyna
K
Bongrazio
Mauro
M
Nitsche
Bianca
B
Hoepfner
Michael
M
Styp-Rekowska
Beata
B
Pries
Axel R
AR
Zakrzewicz
Andreas
A
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
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