Secretory Phospholipase A(2) Enzymes in Acute Lung Injury

The secretory phospholipase A(2) (sPLA(2)) group of secreted enzymes hydrolyze phospholipids and lead to the production of multiple biologically active lipid mediators. sPLA(2)s 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 sPLA(2) isoforms are upregulated in patients with ARDS as well as in multiple ALI preclinical models, and individual sPLA(2)s exert unique roles in regulating ALI pathophysiology. This brief review will summarize the contributions of specific sPLA(2) isoforms as markers and mediators in ALI, supporting a potential therapeutic role for targeting them in ARDS.