Lysophosphatidic acid induces IL‐1β expression and reactive oxygen species production in human macrophages

Lysophosphatidic acid (LPA) is a platelet‐, and oxidized low‐density lipoprotein (ox‐LDL)‐enriched lysophospholipid (LPL). By binding to its cognate G protein coupled‐receptors, LPA is known to regulate multiple biological functions, including inflammation and atherosclerosis. Our previous studies suggested that LPA induces IL‐1β in mouse peritoneal macrophages and J774A.1 mouse macrophage cell line. Furthermore, reactive oxygen species (ROS) production in J774A.1 cells is also elevated by LPA. Based on these observations, we intended to investigate if LPA has similar effects in human system. To answer this question, human macrophages derived from umbilical cord blood were used. By using realtime PCR, western blot, and ELISA, we show that LPA induces IL‐1β expression in both transcriptional and translational levels. In addition, LPA enhances ROS production in these cells through a concentration‐dependent manner as detected by flowcytometry. In conclusion, our results suggested that LPA regulates inflammation‐related behavior of human macrophages.