Alteration of gut microbiota in association with cholesterol gallstone formation in mice

Qihan Wang,Tianquan Han,Hai Hu,Qu Cai,Chuanqi He,Long Jiao,Haidong Sun

doi:10.1186/s12876-017-0629-2

Abstract

BackgroundThe gut microbiome exerts extensive roles in metabolism of nutrients, pharmaceuticals, organic chemicals. Little has been known for the role of gut microbiota in regulating cholesterol and bile acids in association with gallstone formation. This study investigated the changes in the composition of gut microbiota in mice fed with lithogenic diet (LD).MethodsAdult male C57BL/6 J mice were fed with either lithogenic diet (1.25% cholesterol and 0.5% cholic acid) or chow diet as control for 56 days. The fecal microbiota were determined by 16S rRNA gene sequencing.ResultsLD led to formation of cholesterol gallstone in mice. The richness and alpha diversity of gut microbial reduced in mice fed with LD. Firmicutes was significantly decreased from 59.71% under chow diet to 31.45% under LD, P < 0.01, as well as the ratio of Firmicutes to Bacteroidetes. Differences in gut microbiota composition were also observed at phylum, family and genus levels between the two groups.ConclusionOur results suggested that gut microbiota dysbiosis might play an important role in the pathogenesis of cholesterol gallstone formation in mice.

Highlights

The gut microbiome exerts extensive roles in metabolism of nutrients, pharmaceuticals, organic chemicals
Such regulation is crucial for cholesterol metabolism because conversion of cholestrol into bile acids is a key step to get rid of excess cholesterol in the body [16]
lithogenic diet (LD) remodeled the abundance of gut microbiota at different levels The relative abundance of Firmicutes and Bacteroidetes was >86% in the chow group, comprising majority of the gut microbiota (Fig. 1a and b)

Summary

Introduction

The gut microbiome exerts extensive roles in metabolism of nutrients, pharmaceuticals, organic chemicals. Little has been known for the role of gut microbiota in regulating cholesterol and bile acids in association with gallstone formation. Gut microbiota play important roles in regulating the enterohepatic bile acid recycling process through modifying bile acid composition and pool size, and consequentially, influencing intestinal cholesterol absorption [11, 12]. Gut microbiota could profound change the physical characteristics of the bile acids [13,14,15]. Such regulation is crucial for cholesterol metabolism because conversion of cholestrol into bile acids is a key step to get rid of excess cholesterol in the body [16]. Cholic acid (CA) and deoxycholic acid (DCA) have strong antimicrobial activity [19]

Methods

Results

Discussion

Conclusion