High Red Meat Intake Exacerbates Dextran Sulfate-Induced Colitis by Altering Gut Microbiota in Mice.

Dan-Ping Li,Ping Yao,Xiao-Yan Liu,Min Cui,Fang Tan

doi:10.3389/fnut.2021.646819

Abstract

Inflammatory bowel disease (IBD) is a serious hazard to public health, but the precise etiology of the disease is unclear. High intake of red meat diet is closely related to the occurrence of IBD. In this study, we investigated whether the high intake of red meat can increase the sensitivity of colitis and the underlying mechanism. Mice were fed with different levels of red meat for 8 weeks and then the colonic contents were analyzed by 16S rRNA sequencing. Then 3% dextran sulfate sodium was used to induce colitis in mice. We observed the severity of colitis and inflammatory cytokines. We found that high-dose red meat caused intestinal microbiota disorder, reduced the relative abundance of Lachnospiraceae_NK4A136_group, Faecalibaculum, Blautia and Dubosiella, and increased the relative abundance of Bacteroides and Alistipes. This in turn leads to an increase in colitis and inflammatory cytokine secretion. Moreover, we found that high red meat intake impaired the colon barrier integrity and decreased the expression of ZO-1, claudin, and occludin. We also found high red meat intake induced the production of more inflammatory cytokines such as IL-1β, TNF-α, IL-17, and IL-6 and inflammatory inducible enzymes such as COX-2 and iNOS in dextran sulfate sodium-induced colitis. These results suggest that we should optimize the diet and reduce the intake of red meat to prevent the occurrence of IBD.

Highlights

The gut microbiota is an indispensable part of the human body
We found the incidence of inflammatory bowel disease (IBD) was higher than other places in Xinjiang of China, which was believed to be related with their custom of daily high red meat intake for a long time
Mice were fed with different levels of red meat diets for 8 weeks and the colonic contents were analyzed by 16S rRNA gene sequencing

Summary

INTRODUCTION

The gut microbiota is an indispensable part of the human body. It evolves with the host and acts as a natural barrier to help the body digest food, absorb nutrients and maintain health [1]. A cohort study of 67,511 people in France showed that highprotein, high-fat diets of red meat were significantly associated with the onset of IBD [8]. In a prospective study on cancer and nutrition in Europe, red meat, margarine, sunflower oil and corn oil were found to contain large amounts of omega-6 unsaturated fatty acids, while omega-6 unsaturated fatty acids have been shown to increase UC risk [10]. High protein intake causes disturbances in the gut microbiota, which in turn leads to changes in metabolites such as branchedchain fatty acids, amino acids and hydrogen sulfide. These all affect the viability and proliferation of epithelial cells, intestinal barrier function and immune response. We assessed the effects of red meat diet on gut microbiota composition in mice and their subsequent sensitivity to DSS (dextran sulfate sodium)-induced colitis

MATERIALS AND METHODS

RESULTS

DISCUSSION

ETHICS STATEMENT