Diarrhea Caused by High-Fat and High-Protein Diet Was Associated With Intestinal Lactase-Producing Bacteria.

ABSTRACT

BACKGROUND/AIMS: This study aimed to investigate the effect of diarrhea induced by a high-fat and high-protein diet on lactase-producing bacteria in the intestinal contents of mice from the perspective of diarrhea-related genes. MATERIALS AND METHODS: Ten specific pathogen-free Kunming male mice were chosen and randomly divided into the normal group and model group. The mice in the normal group were fed with high-fat and high-protein diet plus gavage of vegetable oil, while those in the model group were fed with general diet plus gavage of distilled water. After successful modeling, the distribution and diversity of lactase-producing bacteria in the intestinal contents were characterized by metagenomic sequencing technology. RESULTS: After high-fat and high-protein diet intervention, Chao1, observed species index, and operational taxonomic units number decreased in the model group (P > .05), while the Shannon, Simpson, Pielou's evenness, and Goods coverage indices increased (P > .05). The principal coordinate analysis showed that the composition of lactase-producing bacteria differed between the normal group and model group (P < .05). The lactase-producing bacterial source in the intestinal contents of mice was Actinobacteria, Firmicutes, and Proteobacteria, of which Actinobacteria was the most abundant phylum. At the genus level, both groups had their unique genera, respectively. Compared to the normal group, the abundance of Bifidobacterium, Rhizobium, and Sphingobium increased, while Lachnoclostridium, Lactobacillus, Saccharopolyspora, and Sinorhizobium decreased in the model group. CONCLUSION: High-fat and high-protein diet altered the structure of lactase-producing bacteria in the intestinal contents, elevating the abundance of dominant lactase-producing bacteria, while decreasing the richness of lactase-producing bacteria, which may further induce the occurrence of diarrhea.