Mechanisms of actions of phytosterols in the intestines [Mécanismes d'actions des phytostérols au niveau intestinal]

摘要

Phytosterols are plant lipids structurally similar to cholesterol. A daily pharmacological dose (2 g/d) reduces serum concentrations of low density lipoprotein cholesterol (LDL-c). Hypocholesterolemic effect is caused by a decreased in intestinal cholesterol absorption, resulting from the loss in its micellar solubility and increases in its fecal excretion. Phytosterols also act directly on cholesterol metabolism by an improved clearance of LDL-c and a reduce activity of Acyl-CoA: cholesterol O-acyltransferase 2 (ACAT2). ACAT2 is a key enzyme that esterifies cholesterol an essential step for its packaging into the neutral lipid core of nascent chylomicrons, prior to its export out of the enterocyte. Phytosterols probably have other actions on cholesterol metabolism, but further studies are needed to understand their functioning.