ANGPTL3, also known as angiopoietin-related protein 3 or angiopoietin-5 (ANGPT5), is a secreted factor in the angiopoietin-like family. Predominantly expressed in the liver, it features a signal peptide, an N-terminal coiled-coil domain, and a C-terminal fibrinogen-like domain. The fibrinogen-like domain binds alpha-5/beta-3 integrins, promoting endothelial cell adhesion and migration, and may regulate angiogenesis. ANGPTL3 also inhibits lipoprotein lipase and endothelial lipase, increasing plasma triglycerides and HDL cholesterol in rodents. By blocking endothelial lipase, it raises HDL-phospholipid levels, enhancing cholesterol efflux.