Fig. 1.

Known mechanisms of action of niacin. Niacin increases circulating HDL particles for peripheral cholesterol scavenging by two described mechanisms: First, by reducing the surface expression of the hepatic HDL receptor β-ATP synthase, which is involved in the endocytosis of HDL particles in the liver, and, second, by increasing the expression of ABCA1, which promotes ApoA-I lipidation and stabilization and thus promotes HDL production. Moreover, niacin reduces the activity of DGAT, which leads to reduced TG synthesis, Apo B degradation, and reduced VLDL and LDL production and circulation.