Absence of intestinal microbiota increases beta-cyclodextrin stimulated reverse cholesterol transport

作者：Mistry Rima H; Verkade Henkjan J; Tietge Uwe J F^*

来源：Molecular Nutrition & Food Research, 2017, 61(5): 1600674.

DOI：10.1002/mnfr.201600674

• beta-cyclodextrin
• Bile
• Germ-free
• Microbiota
• Reverse cholesterol transport

Scope: Non-digestible oligosaccharides are used as prebiotics for perceived health benefits, among these modulating lipid metabolism. However, the mechanisms of action are incompletely understood. The present study characterized the impact of dietary beta-cyclodextrin (beta CD, 10%, w/w), a cyclic oligosaccharide, on sterol metabolism and reverse cholesterol transport (RCT) in conventional and also germ-free mice to establish dependency on metabolism by intestinal bacteria.
Methods and Results: In conventional beta CD-fed C57BL/6J wild-type mice plasma cholesterol decreased significantly (-40%, p< 0.05), largely within HDL, while fecal neutral sterol excretion increased (3-fold, p < 0.01) and fecal bile acid excretion was unchanged. Hepatic cholesterol levels and biliary cholesterol secretion were unaltered. Changes in cholesterol metabolism translated into increased macrophage-to-feces RCT in beta CD-administered mice (1.5-fold, p < 0.05). In germ-free C57BL/6J mice beta CD similarly lowered plasma cholesterol (-40%, p< 0.05). However, beta CD increased fecal neutral sterol excretion (7.5-fold, p < 0.01), bile acid excretion (2-fold, p < 0.05) and RCT (2.5-fold, p < 0.01) even more substantially in germ-free mice compared with the effect in conventional mice.
Conclusion: In summary, this study demonstrates that beta CD lowers plasma cholesterol levels and increases fecal cholesterol excretion from a RCT-relevant pool. Intestinal bacteria decrease the impact of beta CD on RCT. These data suggest that dietary beta CD might have cardiovascular health benefits.

• 出版日期2017-5