Content area
Full Text
Eur J Nutr (2013) 52:869875 DOI 10.1007/s00394-012-0393-6
ORIGINAL CONTRIBUTION
Blueberry anthocyanins at doses of 0.5 and 1 % lowered plasma cholesterol by increasing fecal excretion of acidic and neutral sterols in hamsters fed a cholesterol-enriched diet
Yintong Liang Jingnan Chen Yuanyuan Zuo
Ka Ying Ma Yue Jiang Yu Huang
Zhen-Yu Chen
Received: 23 April 2012 / Accepted: 25 May 2012 / Published online: 9 June 2012 Springer-Verlag 2012
AbstractPurpose The present study investigated the underlying mechanism associated with the hypocholesterolemic activity of blueberry anthocyanins by examining its effect on fecal sterol excretion and gene expression of major receptors, enzymes, and transporters involved in cholesterol metabolism.
Methods Hamsters were divided into three groups and fed a 0.1 % cholesterol diet containing 0 % (CTL), 0.5 % (BL), and 1.0 % (BH) blueberry anthocyanins, respectively, for six weeks. Plasma total cholesterol (TC), triacylglycerols (TAG), and non-high-density lipoproteins cholesterol (non-HDL-C) were measured using the enzymatic kits, and the gene expression of transporters, enzymes, and receptors involved in cholesterol absorption and metabolism was quantied using the quantitative PCR. GC analysis was used to quantify hepatic cholesterol and fecal acidic and neutral sterols.
Results Dietary supplementation of 0.5 and 1.0 % blueberry anthocyanins for 6 weeks decreased plasma TC concentration by 612 % in a dose-dependent manner. This was accompanied by increasing the excretion of fecal neutral and acidic sterols by 2229 % and 4174 %, respectively. Real-
time PCR analyses demonstrated that incorporation of blueberry anthocyanins into diet down-regulated the genes of NPC1L1, ACAT-2, MTP, and ABCG 8. In addition, blueberry anthocyanins were also able to down-regulate the gene expression of hepatic HMG-CoA reductase. Conclusion The cholesterol-lowering activity of blueberry anthocyanins was most likely mediated by enhancing the excretion of sterols accompanied with down-regulation on gene expression of intestinal NPC1L1, ACAT-2, MTP, and ABCG 8.
Keywords Anthocyanins Cholesterol Blueberry
NPC1L1 Sterol excretion
Introduction
Blueberry is one of the most popular fruits and is also rich in anthocyanins [1]. Consumption of blueberry has been shown to prevent the risk of cardiovascular disease, neurodegenerative diseases, diabetes, and cancer. In obese people, consumption of blueberry improves the metabolic syndrome at dietary achievable doses [2]. Daily consumption of blueberry juice demonstrates an improvement in memory function in older adults [3]. Incorporation of blueberry...