Changes in gut microbiota in rats fed a high fat diet correlate with obesity-associated metabolic parameters.

Virginie Lecomte,Mukesh Raipuria,Nadeem O Kaakoush,Margaret J Morris,Hazel M Mitchell,Karina D Huinao,Christopher A Maloney,Pratibha V Nerurkar

doi:10.1371/journal.pone.0126931

Abstract

The gut microbiota is emerging as a new factor in the development of obesity. Many studies have described changes in microbiota composition in response to obesity and high fat diet (HFD) at the phylum level. In this study we used 16s RNA high throughput sequencing on faecal samples from rats chronically fed HFD or control chow (n = 10 per group, 16 weeks) to investigate changes in gut microbiota composition at the species level. 53.17% dissimilarity between groups was observed at the species level. Lactobacillus intestinalis dominated the microbiota in rats under the chow diet. However this species was considerably less abundant in rats fed HFD (P<0.0001), this being compensated by an increase in abundance of propionate/acetate producing species. To further understand the influence of these species on the development of the obese phenotype, we correlated their abundance with metabolic parameters associated with obesity. Of the taxa contributing the most to dissimilarity between groups, 10 presented significant correlations with at least one of the tested parameters, three of them correlated positively with all metabolic parameters: Phascolarctobacterium, Proteus mirabilis and Veillonellaceae, all propionate/acetate producers. Lactobacillus intestinalis was the only species whose abundance was negatively correlated with change in body weight and fat mass. This species decreased drastically in response to HFD, favouring propionate/acetate producing bacterial species whose abundance was strongly correlated with adiposity and deterioration of metabolic factors. Our observations suggest that these species may play a key role in the development of obesity in response to a HFD.

Highlights

Obesity is recognized as a worldwide epidemic, with its prevalence consistently increasing in most countries [1]
high fat diet (HFD) fed rats gained more weight than controls, and three weeks after the commencement of diet, HFD fed rats were significantly heavier than chow fed animals (Chow: 355.4 ± 6.4 g; HFD: 375.9 ± 8.7 g; P
At the end point of the experiment (16 weeks of diet), HFD fed animals were 39% heavier than chow fed animals (P = 4.11E-7; Table 1) and consumed 25% more energy throughout the whole study compared to the chow fed group

Summary

Introduction

Obesity is recognized as a worldwide epidemic, with its prevalence consistently increasing in most countries [1]. Multiple environmental and genetic factors are at play in the development of metabolic diseases. The last decade has seen the emergence of a new player thought to be involved in the onset of the metabolic syndrome associated with obesity: the gut microbiota. Gut Microbiota and Metabolic Parameters in Obese Rats. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript

Methods

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Discussion

Conclusion