A diet high in protein and fiber changes the gut microbiota of colorectal cancer rat model

Abstract

Emerging evidence has suggested that gut microbiota dysbiosis may have a role in colorectal cancer (CRC) progression. Dietary intake high in plant protein and fiber has been associated with reduced risk of this cancer through modulation of gut microbiota. This study aimed to evaluate the effect of the soy protein and fiber diet on gut Lactobacillus and Bifidobacterium of azoxymethane/dextran sodium sulfate (AOM/DSS)- induced rat. A total of twenty-five Wistar rats aged eight weeks were randomly assigned into five groups: the normal control group (NC), the AOM/DSS group, the high protein diet +AOM/DSS group (HP), the high fiber diet +AOM/DSS group (HF), and the combination soy protein and fiber diet+ AOM/DSS group (PF). CRC was induced by injecting 12 mg/kg BW per week of AOM and adding 2% DSS into the drinking water. After four weeks, the rats were sacrificed, and the total DNA was isolated from the cecum. The relative abundance of Lactobacillus and Bifidobacterium was analyzed using quantitative real-time PCR. The fecal cecum samples analysis demonstrated that rats receiving a high soy protein diet (HP), high fiber diet (HF), or both diets (PF) have significantly higher Lactobacillus count compared with the AOM/DSS group that only received a standard diet. In the case of Bifidobacterium, both HP and PF diets showed higher abundance relative to AOM/DSS group, though it was not significant. In conclusion, dietary intake consisting of high soy protein, fiber, or a combination of the two diets modulates the gut microbiota of AOM/DSS-treated rats.