Short-term isocaloric fructose restriction lowers apoC-III levels and yields less atherogenic lipoprotein profiles in children with obesity and metabolic syndrome

Background and aims: Dietary fructose may play a role in the pathogenesis of metabolic syndrome (MetS). In a recently published study of obese children with MetS, we showed that isocaloric fructose restriction reduced fasting triglyceride (TG) and LDL-cholesterol (LDL-C). In these ancillary analyses, we tested the hypothesis that these effects were also accompanied by improved quantitative and qualitative changes in LDL and HDL subclasses and their apolipoproteins; as well as change in VLDL, particularly apoC-III. Methods: Obese children with MetS (n = 37) consumed a diet that matched self-reported macronutrient composition for nine days, with the exception that dietary fructose was reduced from 11.7 +/- 4.0% to 3.8 +/- 0.5% of daily calories and substituted with glucose (in starch). Participants underwent fasting biochemical analyses on Days 0 and 10. HDL and LDL subclasses were analyzed using the Lipoprint HDL and LDL subfraction analysis systems from Quantimetrix. Results: Significant reductions in apoB (78 +/- 24 vs. 66 = 24 mg/dl) apoC-III (8.7 +/- 3.5 vs. 6.5 +/- 2.6 mg/dl) and apoE (4.6 +/- 2.3 vs. 3.6 +/- 1.1 mg/dl), all p < 0.001) were observed. LDL size increased by 0.87 angstrom (p = 0.008). Small dense LDL was present in 25% of our cohort and decreased by 68% (p = 0.04). Small HDL decreased by 2.7% (p < 0.001) and large HDL increased by 2.4% (p = 0.04). The TG/HDL-C ratio decreased from 3.1 = 2.5 to 2.4 +/- 1.4 (p = 0.02). These changes in fasting lipid profiles correlated with changes in insulin sensitivity. Conclusions: Isocaloric fructose restriction for 9 days improved lipoprotein markers of CVD risk in children with obesity and MetS. The most dramatic reduction was seen for apoC-III, which has been associated with atherogenic hypertriglyceridemia. (C) 2016 Elsevier Ireland Ltd. All rights reserved.