Mechanisms of triglyceride clearance

Dietary and liver-derived fatty acids are transported to tissues in the form of triglycerides packed inside triglyceride-rich lipoproteins. These triglyceride-rich lipoproteins include chylomicrons, VLDL, and their remnant particles. Triglyceride-rich lipoproteins are critical for the delivery of fatty acids to tissues throughout the body, and failure to efficiently clear these lipoproteins from the circulation is a risk factor for metabolic disease. Triglyceride clearance encompasses the various pathways by which circulating triglycerides are removed from the bloodstream and taken up into tissues. As triglycerides cannot pass through cell membranes, this clearance involves either the hydrolysis of triglycerides or the uptake of lipoprotein particles. Triglyceride clearance also comprises the regulatory pathways that control which tissues take up triglyceride under various physiological conditions. The proper partitioning of triglyceride to specific tissues is important as ectopic uptake of fatty acids can also result in pathologies including insulin resistance, fatty liver, and lipotoxicity. In this review we discuss the mechanisms that clear triglycerides and triglyceride-rich lipoproteins from the circulation.