Serum metabolomics study on treatment effects of ulcerative colitis of Hudichangrong capsule (HDCRC) in DSS-induced mice

Hudichangrong capsule (HDCRC) is a clinical commonly used formula with obvious curative effects on ulcerative colitis (UC), but its endogenous metabolic mechanism about UC intervention remains largely unknown so far. To study the difference of serum metabolism between HDCRC group and UC group, the UC mice model was induced by DSS, and DAI score, weight and pathological degree of intestinal inflammation were used to assess the effect of HDCRC, of which the serum chemical components were characterized in advance. Then serum untargeted metabolomics based on ultra-performance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry (UPLC-QTOF-MS/MS) was established to collect the metabolic profiles of mice and explore the metabolic changes that occurred after HDCRC treatment, followed by principal component analysis (PCA) and orthogonal projection to latent structures squares-discriminant analysis (OPLS-DA). The PCA model revealed significant differences among the animal groups, and OPLS-DA identified HDCRC-induced changes of 38 potential biomarkers mainly involved in amino acid metabolism, including phenylalanine, tyrosine and tryptophan biosynthesis, and alanine, aspartate and glutamate metabolism. The results implied that endogenous metabolic processes might play a vital role in the treatment progress of UC by HDCRC. Our study also demonstrates that 73 chemical constituents of serum such as emodin, emodin-1-O-glucoside, galloyl-piceid, liquiritigenin and liquiritin with potential treatment effects activity on UC, which exert their therapeutic effects by multiple mechanisms and might be related to their endogenous metabolism. We identified amino acid metabolites associated with UC therapy by HDCRC.