Regulated expression of endothelial lipase in atherosclerosis.

Endothelial lipase (EL) is a major determinant of HDL metabolism and associated with the development of atherosclerosis, however the regulated expression of EL in atherosclerosis is unclear. In this study, we investigated EL expression in rat atherosclerosis and explored the potential mechanisms regulating EL expression by employing LPS on Raw264.7 cells in vitro. Rat atherosclerosis model was established fed on high-cholesterol diet (HCD) combined with vitamin D(2) (VD). Western blotting and immunochemistry staining revealed that EL expression was increased in the aorta, especially the atherosclerotic lesions in HCD rats. LPS increased EL expression in a time and dose dependent manner in Raw264.7 cells and NFkappaB inhibitor, PDTC attenuated the effects of LPS on EL. EMSA revealed that LPS stimulated NFkappaB binding to EL promoter. In summary, EL was upregulated in rat atherosclerosis and LPS stimulates EL expression in vitro through NFkappaB activation. 2009 Elsevier Ireland Ltd. All rights reserved.