Diet-Induced Metabolic Improvements in a Hamster Model of Hypercholesterolemia Are Strongly Linked to Alterations of the Gut Microbiota

Department of Food Science and Technology, University of Nebraska, Lincoln, 68583-0919, USA.
Applied and Environmental Microbiology (Impact Factor: 3.67). 06/2009; 75(12):4175-84. DOI: 10.1128/AEM.00380-09
Source: PubMed

ABSTRACT The mammalian gastrointestinal microbiota exerts a strong influence on host lipid and cholesterol metabolism. In this study, we have characterized the interplay among diet, gut microbial ecology, and cholesterol metabolism in a hamster model of hypercholesterolemia. Previous work in this model had shown that grain sorghum lipid extract (GSL) included in the diet significantly improved the high-density lipoprotein (HDL)/non-HDL cholesterol equilibrium (T. P. Carr, C. L. Weller, V. L. Schlegel, S. L. Cuppett, D. M. Guderian, Jr., and K. R. Johnson, J. Nutr. 135:2236-2240, 2005). Molecular analysis of the hamsters' fecal bacterial populations by pyrosequencing of 16S rRNA tags, PCR-denaturing gradient gel electrophoresis, and Bifidobacterium-specific quantitative real-time PCR revealed that the improvements in cholesterol homeostasis induced through feeding the hamsters GSL were strongly associated with alterations of the gut microbiota. Bifidobacteria, which significantly increased in abundance in hamsters fed GSL, showed a strong positive association with HDL plasma cholesterol levels (r = 0.75; P = 0.001). The proportion of members of the family Coriobacteriaceae decreased when the hamsters were fed GSL and showed a high positive association with non-HDL plasma cholesterol levels (r = 0.84; P = 0.0002). These correlations were more significant than those between daily GSL intake and animal metabolic markers, implying that the dietary effects on host cholesterol metabolism are conferred, at least in part, through an effect on the gut microbiota. This study provides evidence that modulation of the gut microbiota-host metabolic interrelationship by dietary intervention has the potential to improve mammalian cholesterol homeostasis, which has relevance for cardiovascular health.

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    • "The major purpose of our work was to try to evaluate potential changes in the gut microbiota that could be due to the hypolipidemic treatment. Numerous studies have proposed that gut microbiota participates in the regulation of cholesterol metabolism [11] [13] [27]. Changing gut microbiota composition, mainly in favor of Bifidobacterium spp., led to an inhibition of the cholesterol synthesis pathway [13]. "
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    Life sciences 04/2015; 132. DOI:10.1016/j.lfs.2015.04.004 · 2.70 Impact Factor
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    • "and Enterococcus spp. which are known for their anti-inflammatory, immunoregulatory and cholesterol lowering properties through production of short chain fatty acids [5,6]. The most biologically relevant compounds contributing to the sensory and nutritional aspects of olives and olive oil are oleuropein, hydroxytyrosol, quercetin, ferulic acid, caffeic acid, p-hydroxybenzoic acid, protocatechuic acid, 3,4-dyhydroxyphenylacetic acid (3,4-DHPA), homovanillic acid and vanilethanediol, whose metabolic and transcriptional profiling has been recently evaluated during fruit development [7]. "
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    • "We take up a different problem: the reconstruction of organismal composition for each sample. Overall DNA content provides useful information on overall community function, but many physiological and evolutionary processes may be understood only at the organismal level (Partida-Martinez and Hertweck 2005; Martinez et al. 2009). "
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    Genetics 05/2014; 197(3). DOI:10.1534/genetics.114.161299 · 5.96 Impact Factor
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