LYSOPHOSPHATIDYLCHOLINE STIMULATES THE EXPRESSION AND PRODUCTION OF MCP-1 BY HUMAN VASCULAR ENDOTHELIAL-CELLS

Lysophosphatidylcholine (LPC) increased monocyte chemoattractant prote in-1 (MCP-1) messenger RNA concentrations in human umbilical vein endo thelial cells (HUVECs). A time-course study showed that the increase i n MCP-1 mRNA levels peaked at 6 hours after treatment with LPC. The ef fect of LPC on the accumulation of MCP-1 mRNA levels in HUVECs depende d on LPC concentration, and the maximal effect was obtained at 50 mu m ol/LLPC, which induced a sixfold increase in MCP-1 mRNA levels. The am ount of MCP-1 released from HUVECs measured using an enzyme-linked imm unosorbent assay (ELISA) showed a 38% increase in the presence of 50 m u mol/L LPC, but not in the presence of phosphatidylcholine or lysopho sphatidylethanolamine. Coincubation with staurosporine, a potent inhib itor of protein kinase C (PKC) activity, attenuated the LPC-induced in crease in MCP-1 mRNA levels by 53%. These results indicate that LPC ca n induce an increase in MCP-1 mRNA concentrations and stimulate the re lease of MCP-1 protein from HUVECs, and that the effect of LPC on the MCP-1 gene may be mediated through activation of the PKC pathway. (C) 1996 by W.B. Saunders Company.