Effects of diets enriched with two different plant stanol ester mixtures on plasma ubiquinol-10 and fat-soluble antioxidant concentrations

Plant stanols lower intestinal cholesterol absorption. This causes a decrea se in serum low-density lipoprotein (LDL)-cholesterol, despite a compensato ry increase in cholesterol synthesis. We therefore hypothesized that plant stanols also change LDL-cholesterol-standardized concentrations of ubiquino l-10 (a side product of the cholesterol synthesis cascade) and of those fat -soluble antioxidants that are mainly carried by LDL. To examine this, 112 nonhypercholesterolemic subjects consumed low erucic acid rapeseed oil (LEA R)-based margarine and shortening for 4 weeks. For the next 8 weeks, 42 sub jects consumed the same products, while the other subjects received product s with vegetable oil-based stanols (2.6 g sitostanol plus 1.2 g campestanol daily, n = 36) or wood-based stanols (3.7 g sitostanol plus 0.3 g campesta nol daily, n = 34). Consumption of both plant stanol ester mixtures increas ed cholesterol synthesis and lowered cholesterol absorption, as indicated b y increased serum cholesterol-standardized lathosterol and decreased plant sterol concentrations, respectively. Compared with the control group, absol ute plasma ubiquinol-10 concentrations were lowered by 12.3% +/- 18.9% (-0. 14 mug/mL v the control group; P = .004; 95% confidence interval [CI] for t he difference in changes, -0.05 to -0.22 mug/mL) in the vegetable oil-based group and by 15.4% +/- 13.0% (-0.17 mug/mL v the control group; P < .001; 95% CI for the difference, -0.08 to -0.27 <mu>g/mL) in the wood-based group . Changes in LDL-cholesterol-standardized ubiquinol-10 concentrations were not significantly changed. The most lipophylic antioxidants. the hydrocarbo n carotenoids (beta -carotene, alpha -carotene, and lycopene), decreased mo st, followed by the less lipophylic oxygenated carotenoids (lutein/zeaxanth in and beta -cryptoxanthin) and the tocopherols. These reductions were rela ted to the reduction in LDL, which carry most of these antioxidants. The de crease in the hydrocarbon carotenoids, however, was also significantly asso ciated with a decrease in cholesterol absorption. LDL-cholesterol-standardi zed antioxidant concentrations were not changed, except for beta -carotene, which was still, although not significantly, lowered by about 10%. We conc lude that the increase in endogenous cholesterol synthesis during plant sta nol ester consumption does not result in increased LDL-cholesterol-standard ized concentrations of ubiquinol-10, a side product of the cholesterol synt hesis cascade. Furthermore, decreases in absolute fat-soluble antioxidant c oncentrations are related to decreases in LDL-cholesterol. However, for the most lipophylic carotenoids, some of the reduction was also related to the decrease in cholesterol absorption. Copyright (C) 2001 by W.B. Saunders Co mpany.