Influence of minor components of olive oils on the composition and size of TRLs and on macrophage receptors involved in foam cell formation.

Metabolic and epidemiologic studies support the idea that the type of dietary fat is more important than the total amount of fat with respect to the development of atherosclerosis and the risk of cardiovascular heart disease. Dietary fat is carried in CMs (chylomicrons), which can be taken up by macrophages without need of further oxidation, leading to the formation of foam cells and initiating or aggravating the atherogenic process. Evidence from different studies has shown that dietary fat can influence the composition and size of TRLs (triacylglycerol-rich lipoproteins), which might modulate their atherogenicity to a certain extent. In particular, experiments in vitro have shown the anti-atherogenic effects of minor components from olive oil when forming part of TRL, as these particles give minor lipid components the opportunity to interact with the cells implicated in endothelial dysfunction and atherogenesis. However, the exact mechanisms mediating CM uptake by macrophages still remain unclear. Thus further studies are needed to understand how the modifications of TRL composition caused by dietary fats could modulate the expression of macrophage receptors and foam cell formation, or even improve the atherogenic risk of these particles.