11,12-EET suppressed LPS induced TF expression and thrombus formation by accelerating mRNA degradation rate via strengthening PI3K-Akt signaling pathway and inhibiting p38-TTP pathway

Abstract

Epoxyeicosatrienoic acids (EETs), which are synthesized from arachidonic acid by cytochrome P450 epoxygenases, function primarily as autocrine and paracrine effectors in the cardiovascular system. So far, most research has focused on the vasodilatory, anti-inflammatory, anti-apoptotic and mitogenic properties of EETs in the systemic circulation. However, whether EETs could suppress tissue factor (TF) expression and prevent thrombus formation remains unknown. Here we utilized in vivo and in vitro models to investigate the effects and underlying mechanisms of exogenously EETs on LPS induced TF expression and inferior vein cava ligation induced thrombosis. We observed that the thrombus formation rate and the size of the thrombus were greatly reduced in 11,12-EET treated mice，accompanied by decreased TF and inflammatory cytokines expression. Further in vitro studies showed that by enhancing p38 MAPK activation and subsequent tristetraprolin (TTP) phosphorylation, LPS strengthened the stability of TF mRNA and induced increased TF expression. However, by strengthening PI3K-dependent Akt phosphorylation, which acted as a negative regulator of p38-TTP signaling pathway，11,12-EET reduced LPS-induced TF expression in monocytes. In addition, 11,12-EET inhibited LPS-induced NF-κB nuclear translocation by activating the PI3K/Akt pathway. Further study indicated that the inhibitory effect of 11,12-EET on TF expression was mediated by antagonizing LPS-induced activation of thromboxane prostanoid receptor. In conclusion, our study demonstrated that 11,12-EET prevented thrombosis by reducing TF expression and targeting the CYP2J2 epoxygenase pathway may represent a novel approach to mitigate thrombosis related diseases.