Secretory Phospholipase A2 Enzymes in Acute Lung Injury

The secretory phospholipase A2 (sPLA2) group of secreted enzymes hydrolyze phospholipids and lead to the production of multiple biologically active lipid mediators. sPLA2s and their products (e.g., eicosanoids) play a significant role in the pathophysiology of various inflammatory diseases, including life-threatening lung disorders such as acute lung injury (ALI) and the Acute Respiratory Distress Syndrome (ARDS). The ALI/ARDS spectrum of severe inflammatory conditions is caused by direct (such as bacterial or viral pneumonia) or indirect insults (sepsis) that are associated with high morbidity and mortality. Several sPLA2 isoforms are upregulated in patients with ARDS as well as in multiple ALI preclinical models, and individual sPLA2s exert unique roles in regulating ALI pathophysiology. This brief review will summarize the contributions of specific sPLA2 isoforms as markers and mediators in ALI, supporting a potential therapeutic role for targeting them in ARDS.