Therapeutic effects and mechanism of oat β-glucan plus montmorillonite powder on diarrhea in young rats

Oat β-glucan is a prebiotic that affects intestinal microbiota and maintains energy homeostasis. Oat β-glucan helps treat diarrhea and other associated disorders, because it can regulate intestinal microbiota. We investigated the therapeutic effects and mechanism of oat β-glucan combined with montmorillonite powder on diarrhea induced by Senna leaf extract in young Sprague-Dawley rats. Compared with the diarrhea-induced model group (DM), the combined treatment, especially in the group treated with a medium dose of Montmorillonite powder plus oat β-glucan (M+G2), effectively reduced the diarrhea (P < 0.05) and inflammation indices, alleviated damage to the colon, and promoted weight gain in rats. In the combined treatment group, the relative abundance of Firmicutes increased at the phylum level, while the relative abundance of Proteobacteria and Actinobacteria decreased. At the genus level, the Lactobacillus content recovered, and the proportion of conditional pathogens, such as Prevotella and Paraprevotella decreased. M+G2 treatment significantly reduced diarrhea in young rats, restored intestinal microbiota diversity, and promoted the production of short-chain fatty acids (SCFAs). Based on metabolomics, the mechanism of the anti-diarrheal effect of M+G2 treatment may be related to the regulation of glucose and amino acid metabolism. The metabolic micro-environment was improved through the pentose phosphate and vitamin B6 pathways. The core metabolic regulator in metabolic network analysis was L-aspartic acid. Overall, our findings suggest that the combined treatment of oat β-glucan and montmorillonite powder may provide an effective therapeutic strategy for treating diarrhea and associated disorders by regulating the inflammatory biomarkers, SCFAs, and intestinal microbiota.