Fructus Gardeniae-induced gastrointestinal injury was associated with the inflammatory response mediated by the disturbance of vitamin B6, phenylalanine, arachidonic acid, taurine and hypotaurine metabolism

Ethnopharmacological relevance Fructus Gardenia (FG) is a widely used bitter and cold herb for clearing heat and detoxicating. Currently, toxicity of FG and its relative formula has been reported in many clinical and animal studies. However, no systematic research has been carried out on FG-related gastrointestinal (GI) injury which has been emphasized in China since the Ming Dynasty. Aim of the study The purpose of this article is to investigate whether FG could damage GI and explore the mechanisms involved. Material and methods FG was given to male mice by 7-day intragastric administration at average doses of 0.90 g (L group), 1.50 g (M group), and 3.00 g (H group) crude drug/kg FG. Comprehensive understanding of changes in weight, diarrhea degree, stool routine, histomorphology and inflammatory factors of stomach, small intestine, and colon for evaluating the effect of different doses of FG on GI injury. Moreover, metabolomics-based mechanisms exploration of FG on GI injury was carried out via HPLC-Q-TOF/MS analysis on mice urine. Results High dose FG caused GI injury with serious diarrhea, decreased weight, abnormal stool routine, sever alteration in histomorphology of small intestine and colon (mild change in stomach), and significant change in inflammatory factors. The results of metabolomics suggested that 55 endogenous metabolites dispersed in 21 significantly altered metabolic pathways in 3.00 g/kg crude FG treated mice. The hub metabolites of GI injury were mainly related with vitamin B6 metabolism, phenylalanine metabolism, arachidonic acid metabolism, and taurine and hypotaurine metabolism via correlated network analysis. Conclusion FG affected the normal functions of GI via the regulating a variety of metabolic pathways to an abnormal state, and our results provided a research paradigm for the GI-injury of the relative bitter and cold traditional Chinese medicines.