Fig. 9.

S1PR/PKC/ERK/SphK signaling pathways involved in COX-2 expression and PGI-2 release induced by HDL in HUVECs. SphK-2 signaling pathways involved in HDL-induced COX-2 expression and PGI-2 release in HUVECs. Binding of HDL-S1P to S1P receptors resulted transactivation of PKC/ERK linking to SphK-2. The COX-2 transcription is dependently regulated by SphK-2 interaction with CREB. These signaling pathways contribute to COX-2 expression and PGI-2 release in HUVECs. Speculated that the activation of SphK-1 which increases the cytosolic pool of S1P leading to cellular release and the activation of S1P receptors on the cell surface