Lipoprotein carotenoid profiles and the susceptibility of low density lipoprotein to oxidative modification in healthy elderly volunteers

Abstract

The results of this study suggest that, in unsupplemented individuals, plasma can act as a biomarker of carotenoid and gamma-tocopherol concentrations in both LDL and HDL. Supplementation with carotenes or lycopene do not reduce or delay oxidation of LDL. These results support the assumption that carotenoids, such as beta-carotene and lycopene, may show protective effects because they are good markers of fruit and vegetable intake.

Effects of enhanced consumption of fruit and vegetables on plasma antioxidant status and oxidative resistance of LDL in smokers supplemented with fish oil

“…No other correlations between changes in individual or total plasma carotenoid levels and the changes in lag phase LDL were observed between weeks 3 and 6. However, recent carotenoid supplementation studies have failed to show any significant decreases in susceptibility to oxidation (Carroll et al, 2000;Hininger et al, 2001). Hence, the increases in LDL lag phases seen in carotenoid-rich vegetable supplementation studies are probably due to other antioxidant components within the vegetables.…”

Antioxidant Activity and Oxidative Stress: An Overview

“…Most of these studies were carried out in homogeneous solvent systems (i.e. either aqueous or lipid) (Niki et al 1984 ) or artifi cial membranes (liposomes, micelles) in buffer solutions (Fukuzawa et al 1997, Woodall et al 1995, or by using isolated LDLs (Carroll et al 2000 ), cells (Palozza et al 2004 ), and tissue preparations (Palozza and Krinsky 1992b ). However, these types of model systems are far different from an actual biological system such as human serum/plasma, in that plasma is a heterogeneous entity consisting of hydrophilic and lipophilic compartments and contains high concentrations of other components such as protein ( ∼ 600 μ mol/L).…”

Tomato lycopene and cardiovascular prevention

“…Ils ont des propriétés antioxydants in vitro, qui sont en réalité des propriétés antiradicalaires : ils neutralisent l'oxygène singulet (forme active de l'oxygène) et ils piègent les radicaux peroxydes (radicaux libres oxygénés). C'est le cas du lycopène [1,2,6]. Certains comme la lutéine et la zéaxanthine se concentrent au niveau de la macula et sont responsables de la densité maculaire et y jouent un rôle de filtre vis-à-vis de la lumière bleue.…”

“…L'effet antioxydant des caroténoïdes s'exerce sur l'ADN (cancérogenèse), sur les protéines (vieillissement, diabète), sur les LDL (athérosclérose) [1,2,6]. Il est fonction de multiples paramètres physico-chimiques tels que la pression d'oxygène (in vitro), la concentration en caroténoïdes, l'interaction avec d'autres antioxydants tels que la vitamine E (a-tocophérol) qui interagit en synergie avec les caroténoïdes.…”