Coenzyme A and hyperlipoproteinaemias

Coenzyme A (CoA) exerts a favourable effect in lowering plasma lipids in patients with primary hyperlipoproteinaemias of phenotype IV (hypertriglyceridaemia) and of phenotype IIb (combined hyperlipidaemia). The mechanism by which CoA influences plasma lipids may be associated with the well-known role of this coenzyme in the catalysis of acylation reactions and in the control of lipid metabolism. The administration of CoA in animals fed on hyperlipidaemic diets reduces plasma lipid levels and causes a reduction of the hepatic concentrations of triglycerides and/or lipids. Mitochondria and peroxisomes isolated from liver of rats fed on a hyperlipidaemic diet and treated with CoA present an increased oxidation of palmitate. These results suggest that the primary effect of CoA is to increase fatty-acid oxidation in the liver that results in a decrease in endogenous synthesis of triglycerides as well as a reduced formation of VLDL and probably of cholesterol. The stimulation of fatty-acid oxidation in extrahepatic tissues may be also responsible for an increased catabolism of VLDL.