Effect of HDL and apoAI on PGE2 production by monocyte-derived macrophages.

Effect of antiatherogenic high density lipoprotein (HDL) and apolipoprotein AI (apoAI) on production of prostaglandin E2 (PGE2) by human monocyte-derived macrophages was investigated. Macrophages were loaded with acetylated low density lipoprotein followed by incubation with HDL3 or apoAI. PGE2 produced and secreted in culture supernatant was quantified by enzyme immunoassay. HDL3 induced production of PGE2 by macrophages in a time-dependent manner. 24 h after incubation, PGE2 production by HDL3-treated macrophages increased 3.7-fold of that by control cells. ApoAI also induced PGE2 secretion to 2.1-fold, which was significantly less than HDL3. The data indicate that both HDL3 and lipid-free apoAI enhance PGE2 synthesis and secretion by human macrophages and this may further contribute to the protection from atherosclerosis.