Dietary prevention of undernutrition reduces intestinal inflammation associated with an anti-inflammatory profile of gut microbiota in a preclinical model

Patients with inflammatory bowel diseases (IBD) have a high-risk for undernutrition. Undernutrition is associated with higher complications such as an increased mortality rate, a higher disease activity and an impaired quality of life in IBD patients. The aim of this study was to assess whether dietary prevention of undernutrition alleviates intestinal inflammation in mice with colitis. Mice were fed with an enriched diet (ED; 4.7 kcal/g, 38%kcal from milk fat) or a standard diet (SD; 3.9 kcal/g, 8%kcal from milk fat) for 31 days. Colitis was induced by 1% dextran sulfate sodium (DSS) in male C57BL/6 mice for 7 days. Colitis severity was assessed by monitoring inflammation-related biomarkers, such as colon weight/length ratio and fecal calprotectin levels. Cecal microbiota composition was determined by 16S rRNA gene sequencing. Body weight and body composition were recorded. DSS induced a body weight loss and a decrease in lean and fat mass in SD-fed mice, but not in ED-fed mice. In DSS-induced colitis model, only lean mass decrease correlates with colitis severity, characterized by an increase in colon weight/length ratio and fecal calprotectin levels. ED-fed mice exhibit an increase in the abundance of Eisenbergiella tayi and Vescimonas coprocola , which are known short chain fatty acid (SCFA)-producing bacteria, in comparison to SD-fed mice, both in DSS-treated and untreated mice. ED prevents a DSS-induced undernutrition state and promotes the growth of SCFA-producing bacteria, which may have anti-inflammatory properties. This study highlights the importance of better characterizing the link between gut microbiota composition and undernutrition in IBD patients.