Ameliorative effects of Atractylodes macrocephala insoluble dietary fiber on loperamide-induced functional constipation in rats.

In this study, loperamide hydrochloride (LOP) was used to establish a rat model of functional constipation (FC) to explore the mechanism of Atractylodes macrocephala insoluble dietary fiber (AMDF) in improving FC. The results showed that AMDF could increase the fecal water content and small intestinal advancement rate of FC rats, raise the levels of gastrin (GAS), vasoactive intestinal peptide (VIP), and substance P (SP) in serum, reduce the level of somatostatin (SS), reduce the levels of IL-6, TNF-α, and NO in serum, and alleviate the pathological state of colon tissue. The 16S rDNA sequencing results revealed that AMDF could enhance the diversity of the intestinal microbiota and restore the ratio of Firmicutes/Bacteroides (F/B). Metabolomics results show that AMDF treatment can regulate bile secretion, primary bile acid biosynthesis, amino acid metabolic signaling pathways, etc. Meanwhile, AMDF could inhibit the activation of the NF-κB signaling pathway in colon tissue and alleviate intestinal inflammation in FC rats. In conclusion, the research results showed that AMDF can improve the intestinal microbiota and metabolism, and inhibit the intestinal inflammatory response, achieving the effect of relieving FC.