Role of secretory and cytosolic phospholipase A2 enzymes in lysophosphatidylcholine‐stimulated monocyte arachidonic acid release

摘要

>To determine if lysophosphatidylcholine (lysoPC) is able to induce proinflammatory changes in monocytes, its ability to stimulate arachidonic acid (AA) release, a product of phospholipase A2 (PLA₂) activity, has been analyzed. LysoPC increased AA release in THP-1 and Mono Mac6 cells in a time- and concentration-dependent manner. The monocytes expressed both secretory and cytosolic PLA₂ enzymes and AA release was strongly reduced by cellular pretreatment with different PLA₂ inhibitors and by pertussis toxin, an inhibitor of G_i-protein activation. This indicates that both cytosolic and secretory PLA₂ enzymes regulate specific lysoPC receptor-induced AA release, suggesting lysoPC participation in monocyte proinflammatory activation.