Flow-dependent expression of ectonucleotide tri(di)phosphohydrolase-1 and suppression of atherosclerosis
Yogendra Kanthi, … , Hanjoong Jo, David J. Pinsky
Yogendra Kanthi, … , Hanjoong Jo, David J. Pinsky
Published June 29, 2015
Citation Information: J Clin Invest. 2015;125(8):3027-3036. https://doi.org/10.1172/JCI79514.
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Research Article Vascular biology Article has an altmetric score of 32

Flow-dependent expression of ectonucleotide tri(di)phosphohydrolase-1 and suppression of atherosclerosis

Abstract

The ability of cells to detect and respond to nucleotide signals in the local microenvironment is essential for vascular homeostasis. The enzyme ectonucleotide tri(di)phosphohydrolase-1 (ENTPD1, also known as CD39) on the surface of leukocytes and endothelial cells metabolizes locally released, intravascular ATP and ADP, thereby eliminating these prothrombotic and proinflammatory stimuli. Here, we evaluated the contribution of CD39 to atherogenesis in the apolipoprotein E–deficient (ApoE-deficient) mouse model of atherosclerosis. Compared with control ApoE-deficient animals, plaque burden was markedly increased along with circulating markers of platelet activation in Cd39+/–Apoe–/– mice fed a high-fat diet. Plaque analysis revealed stark regionalization of endothelial CD39 expression and function in Apoe–/– mice, with CD39 prominently expressed in atheroprotective, stable flow regions and diminished in atheroprone areas subject to disturbed flow. In mice, disturbed flow as the result of partial carotid artery ligation rapidly suppressed endothelial CD39 expression. Moreover, unidirectional laminar shear stress induced atheroprotective CD39 expression in human endothelial cells. CD39 induction was dependent upon the vascular transcription factor Krüppel-like factor 2 (KLF2) binding near the transcriptional start site of CD39. Together, these data establish CD39 as a regionalized regulator of atherogenesis that is driven by shear stress.

Authors

Yogendra Kanthi, Matthew C. Hyman, Hui Liao, Amy E. Baek, Scott H. Visovatti, Nadia R. Sutton, Sascha N. Goonewardena, Mithun K. Neral, Hanjoong Jo, David J. Pinsky

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Figure 6

Laminar shear stress induces endothelial CD39 expression and nucleotidase activity in vitro and in vivo.

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Laminar shear stress induces endothelial CD39 expression and nucleotidas...
HUVECs and HAECs were exposed to laminar shear stress (15 dynes/cm2) for 48 hours and then assessed for (A) CD39 transcript expression, as measured by quantitative RT-PCR (n = 3–6 per group), and (B) protein expression, as measured by immunoblotting (n = 3–6 per group). Samples exposed to shear stress were compared with static controls. *P < 0.05; **P < 0.005. TLC demonstrated (C, representative plots, and D) enhanced CD39-mediated phosphohydrolysis of radiolabeled nucleotides by intact endothelial cells following laminar shear stress versus static conditions (n = 3–6 per group). *P < 0.05. Partial ligation of left common carotid artery in mice causes disturbed flow and reduced endothelial CD39 expression. Representative ultrasound demonstrating flow velocity profiles in the right (RCA) and left (LCA) common carotid artery revealing (E) disturbed flow (right) 48 hours following partial LCA ligation with diastolic flow reversal in the LCA (indicated by arrow), while contralateral RCA flow remains stable (left) (n = 3 mice). (F) Carotid endothelial expression of Klf2 and Cd39 is decreased under disturbed flow following partial carotid ligation (n = 3 mice) *P < 0.05, Student’s t test. Data are expressed as mean ± SEM.