17α‐Ethinylestradiol rapidly alters transcript levels of murine coagulation genes via estrogen receptor α

Abstract

To cite this article: Cleuren ACA, van der Linden IK, de Visser YP, Wagenaar GTM, Reitsma PH, van Vlijmen BJM. 17a-Ethinylestradiol rapidly alters transcript levels of murine coagulation genes via estrogen receptor a. J Thromb Haemost 2010; 8: 1838-46.Summary. Background: Oral estrogen use is associated with changes in plasma levels of many coagulation proteins. Objective: To gain more insight into the underlying mechanism of estrogen-induced changes in coagulation. Methods: Ovariectomized female mice were used to study the impact of oral 17a-ethinylestradiol (EE) on plasma coagulation, hepatic coagulation gene transcript levels, and dependence on estrogen receptor (ER) a and ERb. Results: Ten days of oral EE treatment resulted in significantly reduced plasma activity levels of factor (F)VIII, FXII, combined FII/FVII/FX and antithrombin, whereas FIX activity significantly increased. Regarding hepatic transcript levels, oral EE caused significant decreases in fibrinogen-c, FII, FV, FVII, FX, FXII, antithrombin, protein C, protein Z, protein Z inhibitor and heparin cofactor II mRNA levels, whereas FXI levels significantly increased and transcript levels of FVIII, FIX, protein S and a 2 -antiplasmin remained unaffected. All EE-induced coagulation-related changes were neutralized by coadministration of the nonspecific ER antagonist ICI182780. In addition, ERa-deficient mice lacked the EE-induced changes in plasma coagulation and hepatic transcript profile, whereas ERb-deficient mice responded similarly to non-deficient littermate controls. A crucial role for the ER was further demonstrated by its rapid effects on transcription, within 2.5-5 h after EE administration, suggesting a short chain of events leading to its final effects. Conclusions: Oral EE administration has a broad impact on the mouse coagulation profile at the level of both plasma and hepatic mRNA levels. The effects on transcription are rapidly induced, mostly downregulatory, and principally mediated by ERa.

Role of platelets, neutrophils, and factor XII in spontaneous venous thrombosis in mice

“…8,9 Mouse heads were fixed in 4% formaldehyde. All experimental procedures were approved by the Institutional Animal Welfare Committee.…”

“…8,9 siRNA-mediated hepatic silencing of Serpinc1 and Proc silencing were routinely confirmed. 6 Liver fibrin deposition was determined by immunoblotting using the monoclonal antibody 59D8.…”

“…11 Plasma FXII activity was determined by using an activated partial thromboplastin time (aPTT)-based assay with FXII-deficient human plasma and C57BL/6J mouse pool plasma for calibration. 9 Plasma nucleosome levels and thrombin generation (tissue factor and ellagic acid-induced) were determined as described. 12,13 Phenotype assessment…”

Intrinsic Coagulation Activation and the Risk of Arterial Thrombosis in Young Women

“…3 Furthermore, a recent murine study suggests that estrogens influence the transcription of more coagulation proteins. 15 The mechanism(s) by which these proteins are involved in the pathogenesis of IS in young women still have to be established. Perhaps such an increased activity of these proteins results in an imbalance of the several systems in which the intrinsic coagulation proteins are involved (eg, coagulation, fibrinolysis, and inflammation).…”

“…14 Because estrogens could have an impact on transcription levels of coagulation proteins, especially FXII because of an estrogen receptive element in the promoter of the F12 gene, the relation between (intrinsic) coagulation proteins and the risk of arterial thrombosis is potentially different in women. 3,15 It is unknown to what extent intrinsic coagulation proteins are involved in the pathophysiological processes that lead to the different forms of arterial thrombosis, especially in young women. This patient group is of particular interest because of their use of estrogen-containing medication (ie, oral contraceptives).…”