Cardiovascular Benefits of Phenol-Enriched Virgin Olive Oils: New Insights from the Virgin Olive Oil and HDL Functionality (VOHF) Study

Abstract

Scope: The main findings of the "Virgin Olive Oil and HDL Functionality" (VOHF) study and other related studies on the effect of phenol-enriched virgin olive oil (VOO) supplementation on cardiovascular disease are integrated in the present work.

Methods and results: VOHF assessed whether VOOs, enriched with their own phenolic compounds (FVOO) or with those from thyme (FVOOT), improve quantity and functionality of HDL. In this randomized, double-blind, crossover, and controlled trial, 33 hypercholesterolemic subjects received a control VOO (80 mg kg-1 ), FVOO (500 mg kg-1 ), and FVOOT (500 mg kg-1 ; 1:1) for 3 weeks. Both functional VOOs promoted cardioprotective changes, modulating HDL proteome, increasing fat-soluble antioxidants, improving HDL subclasses distribution, reducing the lipoprotein insulin resistance index, increasing endogenous antioxidant enzymes, protecting DNA from oxidation, ameliorating endothelial function, and increasing fecal microbial metabolic activity. Additional cardioprotective benefits were observed according to phenol source and content in the phenol-enriched VOOs. These insights support the beneficial effects of OO and PC from different sources.

Conclusion: Novel therapeutic strategies should increase HDL-cholesterol levels and enhance HDL functionality. The tailoring of phenol-enriched VOOs is an interesting and useful strategy for enhancing the functional quality of HDL, and thus, it can be used as a complementary tool for the management of hypercholesterolemic individuals.

Keywords: HDL functionality; cardiovascular; phenolic compounds; polyphenols; virgin olive oil.

Conflict of interest statement

Conflict of Interest

The authors declare no conflict of interest.

© 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Figures

Figure 1.

Scheme integrating the results and the relationships of the phenol-enriched VOOs effect on the HDL functionality in the VOHF study. Color boxes denote the different effects on HDL of phenol-enriched VOOs tested in the VOHF study: red, lipoprotein profile; blue, glucose metabolism; mint, CEC; yellow, HDL monolayer fluidity; purple, HDL antioxidant capacity; orange, HDL vasodilatory function; green, protein cargo; light blue, HDL anti-inflammatory properties. ApoA-I, apolipoprotein A-I; EC, esterified cholesterol; FC, free cholesterol; FVOO, functional VOO enriched with its own phenolic compounds; FVOOT, functional VOO enriched with its own phenolic compounds plus additional complementary ones from thyme; HDL, high-density lipoprotein; HDL-c, HDL cholesterol; HDL-P, HDL particle number; IRH, ischemic reactive hyperaemia; l-HDL, large HDL particles; LCAT, lecithin–cholesterol acyltransferase; LDL-P, low-density lipoprotein particle number; LP-IR, lipoprotein insulin resistance index; PL, phospholipids; PON, paraoxonase; s-HDL, small HDL particles; TC, total cholesterol; and VOO, virgin olive oil.

Figure 2.

Scheme integrating the main results of the MEFOPC project. Caco-2, human cancer colon cell line; HAEC, human aortic endothelial cells, MAPK, mitogen-activated protein kinase.