Ulcerative colitis (UC) is a common disease of the digestive system that is challenging to treat. Gegen Qinlian Decoction (GQD), which is an ancient classic formula in Chinese medicine, is effective at alleviating the symptoms of UC, but comprehensive research on its mechanism of action has not been performed. Here, we explored the material basis and potential molecular mechanism underlying GQD-mediated protection against UC by integrated metabolomics and network pharmacology. First, differentially expressed metabolites were screened and identified via a metabolomics approach, and the metabolic pathway was analyzed via MetaboAnalyst. Second, a protein–protein interaction (PPI) network was constructed to identify hub genes that encode metabolic enzymes. Third, the differentially expressed metabolites were used to construct a compound-reaction-enzyme-gene network. Finally, the metabolites were compared with relevant active components for molecular docking, molecular dynamics (MD) simulation, and verification experiment. GQD intervention alleviated UC in mice and significantly inhibited metabolic dysfunction in mice with UC; specifically, GQD reversed the abnormal changes in metabolites in the colon and serum, and regulated the arachidonic acid metabolism, tryptophan metabolism, glycerophospholipid metabolism, and purine metabolism pathways. Further literature review and molecular docking analysis with targeted MD simulation and Poisson-Boltzmann surface area (MM-PBSA) analysis were performed, revealing that GQD may inhibit the disruption of arachidonic acid metabolism and tryptophan metabolism by suppressing PTGS2 and CYP450 protein expression; these results were verified by qRT-PCR, WB, and surface plasmon resonance (SPR) assays. Our experiments indicated that GQD alleviated UC in mice by systematically regulating arachidonic acid metabolism and tryptophan metabolism, supporting further research and the development of GQD as a novel drug for ameliorating UC.
Read full abstract