First Author | Barbieri SS | Year | 2012 |
Journal | Circulation | Volume | 126 |
Issue | 11 | Pages | 1373-84 |
PubMed ID | 22865892 | Mgi Jnum | J:202193 |
Mgi Id | MGI:5517641 | Doi | 10.1161/CIRCULATIONAHA.112.097295 |
Citation | Barbieri SS, et al. (2012) Cyclooxygenase-2-derived prostacyclin regulates arterial thrombus formation by suppressing tissue factor in a sirtuin-1-dependent-manner. Circulation 126(11):1373-84 |
abstractText | BACKGROUND: Selective inhibitors of cyclooxygenase (COX)-2 increase the risk of myocardial infarction and thrombotic events, but the responsible mechanisms are not fully understood. METHODS AND RESULTS: We found that ferric chloride-induced arterial thrombus formation was significantly greater in COX-2 knockout compared with wild-type mice. Cross-transfusion experiments excluded the likelihood that COX-2 knockout platelets, despite enhanced aggregation responses to collagen and thrombin, are responsible for increased arterial thrombus formation in COX-2 knockout mice. Importantly, we observed that COX-2 deletion decreased prostacyclin synthase and production and peroxisome proliferator-activated receptor- and sirtuin-1 (SIRT1) expression, with consequent increased upregulation of tissue factor (TF), the primary initiator of blood coagulation. Treatment of wild-type mice with a prostacyclin receptor antagonist or a peroxisome proliferator-activated receptor-delta antagonist, which predisposes to arterial thrombosis, decreased SIRT1 expression and increased TF activity. Conversely, exogenous prostacyclin or peroxisome proliferator-activated receptor-delta agonist completely reversed the thrombotic phenotype in COX-2 knockout mice, restoring normal SIRT1 levels and reducing TF activity. Furthermore, inhibition of SIRT1 increased TF expression and activity and promoted generation of occlusive thrombi in wild-type mice, whereas SIRT1 activation was sufficient to decrease abnormal TF activity and prothrombotic status in COX-2 knockout mice. CONCLUSIONS: Modulation of SIRT1 and hence TF by prostacyclin/peroxisome proliferator-activated receptor-delta pathways not only represents a new mechanism in controlling arterial thrombus formation but also might be a useful target for therapeutic intervention in the atherothrombotic complications associated with COX-2 inhibitors. |