Apolipoprotein A5: Extracellular and Intracellular Roles in Triglyceride Metabolism

Title:Apolipoprotein A5: Extracellular and Intracellular Roles in Triglyceride Metabolism

Volume: 16 Issue: 12

Author(s): Trudy M. Forte and Robert O. Ryan

Affiliation:

Keywords: Apolipoprotein A5, hepatocytes, hypertriglyceridemia, lipid-droplets, non-alcoholic fatty liver disease, single nucleotide polymorphisms, triglyceride-rich lipoproteins.

Abstract: This review addresses two major functions of apolipoprotein (apo) A5 including (1) its role in maintaining normal plasma levels of circulating triglyceride (TG) and (2) its role as a component of hepatic lipid droplets. ApoA5 is synthesized solely in the liver and circulating concentrations are extremely low. In the plasma, ApoA5 associates with TG-rich lipoproteins and enhances TG hydrolysis and remnant lipoprotein clearance. ApoA5 loss-of-function single nucleotide polymorphisms are associated with reduced lipolysis, poor remnant clearance and concomitantly, hypertriglyceridemia. Although there have been substantial breakthroughs in understanding pathophysiology associated with secreted ApoA5, there is a paucity of knowledge on the functionality of intracellular ApoA5. However, recent studies indicate that overexpression of intracellular ApoA5 is positively associated with accumulation of TG-rich lipid droplets in hepatocytes. It is thought that ApoA5 may have a causal role in non-alcoholic fatty liver disease (NAFLD) and thus, may serve as a target for developing therapeutics for NAFLD.

Cite this article as:

Forte M. Trudy and Ryan O. Robert, Apolipoprotein A5: Extracellular and Intracellular Roles in Triglyceride Metabolism, Current Drug Targets 2015; 16 (12) . https://dx.doi.org/10.2174/1389450116666150531161138