Metabolic regulation by secreted phospholipase A(2)

Within the phospholipase A(2) (PLA(2)) superfamily that hydrolyzes phospholipids to yield fatty acids and lysophospholipids, the secreted PLA(2) (sPLA(2)) enzymes comprise the largest family that contains 11 isoforms in mammals. Individual sPLA(2)s exhibit unique distributions and specific enzymatic properties, suggesting their distinct biological roles. While sPLA(2)s have long been implicated in inflammation and atherosclerosis, it has become evident that they are involved in diverse biological events through lipid mediator-dependent or mediator-independent processes in a given microenvironment. In recent years, new biological aspects of sPLA(2)s have been revealed using their transgenic and knockout mouse models in combination with mass spectrometric lipidomics to unveil their target substrates and products in vivo. In this review, we summarize our current knowledge of the roles of sPLA(2)s in metabolic disorders including obesity, hepatic steatosis, diabetes, insulin resistance, and adipose tissue inflammation.