P107 DHA decreases ET-1 production in cultured human umbilical vein endothelial cells

Abstract

This study was performed to evaluate the effects of docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA) on endothelin-1 (ET-1), ICAM or TNFα production in human umbilical vein endothelial cells (HUVECs). We hypothesized DHA and EPA, and troglitazone would decrease inflammatory proteins on human vascular endothelium and that they may decrease the vaso-active material ET-1 with common action mechanism, as PPARγ ligands. HUVECs were incubated with DHA, EPA or troglitazone for 24 h dose dependently. Western blottings for PPARγ were done for each three materials. The cells were treated with LPS or IL-1β (10 μg/ml) in order to provoke inflammatory or immunologic reactions, and incubated for 8 h. ELISA tests for ET-1, ICAM and TNFα were done from the cell culture media. ET-1 production was not changed by administration of LPS or IL-1β in control cells. However, ET-1 production significantly decreased in DHA-pretreated cell media in doses of 20 μM, 50 μM and 100 μM in a dose-dependent manner when compared to the control. EPA and troglitazone could decrease the ET-1 production (in doses of 10 μM, 50 μM, 100 μM, and 20 μM, 50 μM, 100 μM, respectively), but not in a dose-dependent manner in LPS-treated HUVECs. ICAM and TNFα productions were increased significantly by either LPS or IL-1β treatment, but pretreatment with any of the three materials did not decrease ICAM or TNFα productions significantly. We could see the significantly increased activity of PPARγ by Western blotting with DHA, EPA or troglitazone, but their activities were not related to the ET-1 production changes. In conclusion, this study speculates that DHA is consistently decrease the vaso-active protein, ET-1, whether in conditions of inflammation or not in human vascular endothelial system. DHA supplementation would be helpful to pregnant women having hypertensive diseases by decreasing vascular endothelial ET-1 production.