Chicory, a typical vegetable in Mediterranean diet, exerts a therapeutic role in established atherosclerosis in apolipoprotein E-deficient mice

Scope: Since protocatechuic acid exerts an atheroprotective role, we investigated how chicory (Cichorium intybus L. var. foliosum, Belgian endive) rich in protocatechuic acid, a typical vegetable in Mediterranean diet, affects preestablished atherosclerosis progression. Methods and results: Apolipoprotein E-deficient mice fed AIN diets containing 0.5% freeze-dried chicory for 10 weeks displayed a reduction in lesion size with a concomitant improvement in lesion stability indicated by fewer macrophages and more collagen content. Chicory consumption suppressed aortic cholesterol accumulation and intercellular adhesion molecule-1, vascular cell adhesion molecule-1, and monocyte chemoattractant protein-1 expression, whereas it increased aortic ATP-binding cassette transporter A1 (ABCA1) and G1 (ABCG1) expression. Furthermore, chicory consumption improved peritoneal macrophage phenotype with less cellular cholesterol associated with an enhancement of cholesterol efflux capacity through upregulation of ABCA1 and ABCG1, less cellular oxidative stress associated with an inhibition of nicotinamide adenine dinucleotide phosphate oxidase activity, and weaker inflammatory responses associated with an inhibition of nuclear factor-kappa B activation. Interestingly, ABCA1 and ABCG1 silencing tended to completely block beneficial effects of chicory in peritoneal macrophages. Conclusion: Chicory exerts an atheroprotective role in mice possibly by regulating lesional macrophage content and phenotype, suggesting that chicory is one underrated contributor to Mediterranean Diet-induced atheroprotection.