To explore the mechanism of Xiaoyao Yiji decoction in the treatment of IBS-D by the 16s rRNA sequencing combined with metabolomics

Abstract:

Objective To investigate the mechanism of action of Xiaoyao Yiji decoction in the treatment of Diarrhea-predominant irritable bowel syndrome（IBS-D） by 16s rRNA sequencing combined with metabolomics.Methods A total of 10 IBS-D patients who met the inclusion criteria in the outpatient clinic of the Department of Shaanxi Hospital of Chinese Medicine were enrolled，feces samples were collected before and after treatment by Xiaoyao Yiji decoction，the differences of intestinal flora composition and community structure，and screened differential flora were analyzed by the 16S rRNA. The differential expressed metabolites and pathways were screened and analyzed by fecal metabolomics analysis.Results Xiaoyao Yiji decoction can significantly regulate the abundance of intestinal firmicutes，proteobacteria，actinomycetes，Bacteroides，Megamonas，Escherichia shigella，Bifidobacterium，P. pristrilla，and other flora in IBS-D patients and identify 21 disease-related differential metabolites involving 16 metabolism-related pathways，among which the pathway affects phenylalanine metabolism the most and histidine metabolism followed. With the Xiaoyao Yiji decoction treatment，the gut microbiota in IBS-D patients had been changed as Firmicutes，Proteobacteria，Actinobacteria，Bacteroidetes in the phylum level and Firmicutes increased significantly. Monelensis，Escherichia-Shigella，Bifidobacterium，Faecalibacterium，Blautia were the dominant flora. The diversity analysis showed that the species richness of the intestinal flora group decreased after the treatment，but the evenness and diversity increased，and the community structure and composition were basically consistentdiversity. Negativicutes，Veillonellales_Selenomonadales is specific flora with statistical differences between groups. Twenty-one disease-related differential metabolites were selected，involving in 16 metabolism-related pathways，with the most prominent effects on phenylalanine metabolism.Conclusion Xiaoyao Yiji decoction may achieve the therapeutic effect of IBS-D by regulating the intestinal flora of Firmicutes and Veillonellales，regulating phenylalanine metabolism and histidine metabolism pathways.