Abstract 18760: Interactions Between Dietary Fiber and Gut Microbiota Modulate the Development of Atherosclerosis
Diets rich in plant polysaccharides (i.e., fiber) confer protection against cardiovascular disease (CVD). Some of these benefits are derived from the interactions between carbohydrates that reach the distal gut and microbes, via production of short chain fatty acids (SCFA, e.g., acetate, propionate and butyrate). However, there are large interpersonal differences in gut microbiota composition and in the amounts of SCFA produced in response to dietary fiber, and it is not clear whether the capacity of a microbiota to produce SCFA from fiber impacts the beneficial effects associated with its consumption. We tested whether changes in the representation of a prominent human gut butyrate-producing species, R. intestinalis, modulates the development of atherosclerosis in mice fed diets that vary in the amount of fiber. Germ-free ApoE knockout mice were orally gavaged with the following microbial mixtures: (i) a “core” community which included nine species commonly found in the human microbiota that have little or no capacity to produce butyrate; or (ii) the same “core” community plus R. intestinalis. Mice were fed either a low- or high-plant polysaccharide (LPP or HPP) diet for sixteen weeks after microbial inoculation. Introduction of R. intestinalis did not affect cecal butyrate levels or development of atherosclerosis in mice fed the LPP diet. In contrast, it resulted in a 5-fold increase in cecal butyrate levels and a significant reduction in the size of the atherosclerotic lesions in mice fed the HPP diet. Additionally, reduced atherosclerotic lesions were associated with lower expression levels of Tnfα and Vcam1 in the aorta from mice colonized with R. intestinalis. These results demonstrate an athero-protective effect of R. intestinalis in the presence of dietary plant polysaccharides and provide a tractable system to dissect diet-microbe interactions relevant to CVD. Moreover, our results suggest that the metabolic potential of the gut microbiota should be considered when making dietary recommendations to prevent development of CVD.
Author Disclosures: K. Kasahara: None. R.L. Kerby: None. K.A. Romano: None. E.I. Vivas: None. M. Mehrabian: None. A.J. Lusis: None. F.E. Rey: None.
- © 2016 by American Heart Association, Inc.