Vascular lipases, inflammation and atherosclerosis

Members of the lipase family that include lipoprotein lipase, hepatic lipase and endothelial cell lipase play a central role in triglyceride and phospholipid hydrolysis. Because the site of action of these lipases is the endothelium, the endothelium is constantly exposed to products of lipolysis. These lipolysis products could elicit pro- or anti-inflammatory effects in endothelial as well as surrounding cells. These effects could be transient or long-term depending on the nutritional state. While lipolysis is per se anti-atherogenic due to its triglyceride lowering activity, it could also be pro-atherogenic due to prolonged exposure of endothelium to lipolysis products. In addition, lipoprotein lipase expressed in macrophages appears to be pro-atherogenic independent of plasma lipoproteins. In this review we summarize these pro- and anti-inflammatory consequences of lipolysis with respect to atherosclerosis.