apoC2

Apolipoprotein C-II (apoC-II) is a critical regulator of triglyceride-rich lipoprotein metabolism and functions as an essential cofactor for lipoprotein lipase (LPL), the enzyme responsible for hydrolyzing plasma triglycerides carried by chylomicrons and very-low-density lipoproteins (VLDL)^[1]. ApoC-II is present on chylomicrons, VLDL, low-density lipoproteins (LDL), and high-density lipoproteins (HDL), where it coordinates lipid utilization and lipoprotein remodeling through LPL activation^[1][2]. Mechanistically, the C-terminal helix of apoC-II mediates the interaction with LPL, whereas the N-terminal region primarily contributes to lipid binding^[2]. Through activation of LPL-dependent triglyceride hydrolysis, apoC-II regulates fatty acid delivery to peripheral tissues and supports the clearance of triglyceride-rich lipoproteins from circulation^[1][2]. Deficiency of apoC-II impairs LPL activity and causes severe hypertriglyceridemia and familial chylomicronemia, establishing the protein as a key determinant of plasma lipid homeostasis^[1][2]. Disease relevance is further supported by observations that altered apoC-II levels are associated with changes in triglyceride-rich particles and HDL distribution, processes linked to cardiovascular risk^[2]. Compared with related apolipoprotein C family members, apoC-II is distinguished by its role as an activator of LPL, whereas apoC-III functions predominantly as an inhibitor of LPL-mediated lipolysis^[3][4]. This functional opposition makes apoC-II a valuable experimental target for studies investigating triglyceride metabolism, hypertriglyceridemia, lipoprotein clearance, and LPL-dependent metabolic pathways^[1][2].

References: