Phenolic content of extra virgin olive oil is essential to restore endothelial dysfunction but not to prevent vascular inflammation in atherosclerotic lesions of Apo E deficient mice

• Endothelial dysfunction was restored by polyphenol enriched VOO.
• EVOO reduced inflammation in atherosclerotic plaque independently of its polyphenol content.
• Polyphenol-enriched VOO reduced atherosclerotic plaque lipid content.

Extra Virgin Olive Oil (EVOO) contains monounsaturated fatty acids and multiple minor components with biological properties and health benefits. We evaluate whether a diet supplemented on Oleaster®(OT), an EVOO obtained by a new process aimed to increase phenolic composition, provided additional benefits to those observed in the animals fed a diet rich in traditional EVOO on atherosclerosis development and vasomotor function in aortic vessel of ApoE−/− mice. Results were compared with those obtained in mice fed an EVOO, a standard diet (SD) or a high fat diet (HFD) rich in saturated fatty acids. Both extra-virgin olive oils reduced macrophage accumulation and protein expression of iNOS, ICAM-1 and VCAM-1, TNF-α and NF-κB, independently of its phenolic content toward values found in SD. Superoxide anion production was also reduced to the same extent in Apo E−/− mice fed EVOO or OT. Endothelial function assessed by ACh-induced vasodilatation, and lipid accumulation within the atherosclerotic plaque were restored in OT- but not in EVOO-fed mice. We conclude that EVOO contribute to prevent the inflammatory markers of atherosclerosis plaque progression but the polyphenolic content is not responsible for this effect. However, those compounds are able to restore endothelial function and to reduce lipid accumulation within the atherosclerotic lesion.