Apolipoproteiner

Apolipoproteiner is not a standard term in English, and it most likely refers to apolipoprotein, the protein component of lipoprotein particles. In humans, apolipoproteins are essential for the assembly, stabilization, transport, and receptor recognition of lipids carried in the bloodstream by lipoproteins such as chylomicrons, VLDL, LDL, and HDL.

Most apolipoproteins are encoded by a family of APO genes. Notable examples include APOA1, APOA2, APOB, APOC1, APOC2, APOC3, and APOE. Apolipoprotein B exists in two forms produced from the same gene through RNA editing: ApoB-100, produced mainly in the liver as part of VLDL and LDL particles, and ApoB-48, produced in the intestine for chylomicrons. ApoA-I is the major structural protein of HDL and activates enzymes such as lecithin–cholesterol acyltransferase (LCAT). ApoE serves as a ligand for hepatic receptors and also facilitates brain lipid transport. ApoC-II activates lipoprotein lipase, promoting triglyceride hydrolysis, while ApoC-III can inhibit lipolysis and delay clearance of triglyceride-rich particles.

Apolipoproteins influence lipid metabolism and cardiovascular risk. Genetic variants, such as APOE alleles, affect cholesterol transport and disease susceptibility, including risks for coronary artery disease and, in some contexts, neurodegenerative conditions. Clinically, apolipoprotein levels are measured to assess particle number and atherogenic burden, sometimes providing information beyond traditional cholesterol measurements. Because apolipoproteiner is not standard terminology, it is typically understood as a linguistic variant or misspelling of apolipoprotein.