[Integrated strategy for mechanism of Shenling Baizhu San in treating ulcerative colitis based on colonic metabolomics and network pharmacology]

Shenling Baizhu San(SLBZS) is a commonly used medicine for the treatment of ulcerative colitis(UC). This study aims to explore the mechanism of SLBZS in treating UC by using colonic metabolomics and network pharmacology. BALB/c mice were randomly divided into four groups: a blank group, a model group, an SLBZS group, and a sulfasalazine group. UPLC-Q-TOF-MS/MS technology was utilized to analyze the metabolic profiles of colonic tissue in mice, and differential metabolites and related metabolic pathways were screened. Based on the online database, active ingredients, action targets, and UC disease targets of SLBZS were screened. The protein-protein interaction(PPI) network of core targets of SLBZS in treating UC was constructed using STRING and Cytoscape 3.9.1. Gene Ontology(GO) functional and Kyoto Encyclopedia of Genes and Genomes(KEGG) pathway enrichment analyses were performed using the DAVID database. A "metabolite-reaction-enzyme-gene" network was constructed to conduct a combined analysis of metabolomics and network pharmacology. SLBZS reversed the levels of 25 metabolites involved in various pathways such as D-glutamine and D-glutamate metabolism, caffeine metabolism, sphingolipid metabolism, arginine biosynthesis, lysine degradation, alanine, aspartate, and glutamate metabolism, glycerophospholipid metabolism, and pyrimidine metabolism in UC colonic tissue. 47 core targets of SLBZS in treating UC were involved in pathways including the MAPK signaling pathway, TNF signaling pathway, Toll-like receptor signaling pathway, lipid and atherosclerosis, inflammatory bowel disease, and Th17 cell differentiation. Integrated analysis showed that glycerophospholipid metabolism and pyrimidine metabolism were key metabolic pathways in the treatment of UC with SLBZS. The results suggested that SLBZS improved colonic mucosal morphology by regulating colonic metabolites, down-regulated the expression of inflammation-related core target genes to reduce inflammation levels, and alleviated lipid metabolism disorders, thereby exerting a therapeutic effect on UC.