Apolipoproteins are proteins that bind lipids (fat or cholesterol) to form lipoproteins, which are important for transporting lipids through the lymphatic and circulatory systems. There are several types of apolipoproteins, each with different physiologic roles.
Apo A-1 ("Activates") is responsible for the activation of LCAT and the esterification of cholesterols.
Apo B-48 ("Bombs Blood") plays a role in the secretion of chylomicrons from the GI tract into the blood.
Apo B-100 ("Binds") enables binding of LDL and VLDL to cells including tissue cells and hepatocytes.
Apo E ("Empties") is responsible for the hepatic emptying of chylomicrons (from the mesenteric arteries).
Apo C-2 ("Cuts") is a co-factor of lipoprotein lipase, which cleaves lipids to release free fatty acids.
Find Apolipoproteins and the Dyslipidemias among Pixorize's visual mnemonics for the USMLE Step 1 and NBME Shelf Exams.