Calcium Signaling of Lysophosphatidylethanolamine through LPA(1) in Human SH-SY5Y Neuroblastoma Cells

Lysophosphatidylethanolamine (LPE), a lyso-type metabolite of phosphatidylethanolamine, has been reported to be an intercellular signaling molecule. LPE mobilizes intracellular Ca(2+) through G-protein-coupled receptor (GPCR) in some cells types. However, GPCRs for lysophosphatidic acid (LPA) were not implicated in the LPE-mediated activities in LPA GPCR overexpression systems or in SK-OV3 ovarian cancer cells. In the present study, in human SH-SY5Y neuroblastoma cells, experiments with LPA(1) antagonists showed LPE induced intracellular Ca(2+) increases in an LPA(1) GPCR-dependent manner. Furthermore, LPE increased intracellular Ca(2+) through pertussis-sensitive G proteins, edelfosine-sensitive-phospholipase C, 2-APB-sensitive IP(3) receptors, Ca(2+) release from intracellular Ca(2+) stores, and subsequent Ca(2+) influx across plasma membranes, and LPA acted on LPA(1) and LPA(2) receptors to induce Ca(2+) response in a 2-APB-sensitive and insensitive manner. These findings suggest novel involvements for LPE and LPA in calcium signaling in human SH-SY5Y neuroblastoma cells.