Effect of virgin olive oil phenolic compounds on in vitro oxidation of human low density lipoproteins

Background and Aim: Substantial evidence suggests that oxidative modificati ons of low density lipoproteins (LDL) critically contribute to the pathogen esis and progression of human atherosclerosis. Oxidized LDL (oxLDL) are pre sent in atherosclerotic plaques and contain oxysterols that exhibit a varie ty of adverse biological activities, Antioxidants have also been shown to p revent LDL modification. We have therefore assessed the efficacy of virgin olive oil phenolic compounds in preventing oxidative modifications of human LDL oxidized by UV light. Methods and Results: Cholesterol oxides formed during LDL photo-oxidation w ere determined by UV-HPLC in the presence of different concentrations of ph enolic compounds and their pure components (tyrosol and oleuropein), and pr obucol, a widely used synthetic antioxidant. Electrophoretic mobility was a lso assayed The results demonstrate that phenolic compounds are much more p otent in preventing cholesterol oxide formation and apoproteic moiety modif ication than their pure components and probucol, Conclusions: The beneficial effects of a Mediterranean diet may be ascribab le not only to the high unsaturated/saturated fatty acid ratio characterist ic of olive oil, but also to the unique antioxidant properties of its pheno lic compounds. (C) 1999, Medikal Press.