Metabolite 5-MT ameliorate colitis via modulating gut microbiota and TLR4 pathway

the level of serum metabolite 5-methyl-dl-tryptophan (5-MT) was reduced by DSS and restored by ASP-Ag-AP, which had correlation with Bacteroides, Alistipes, Staphylococcus and pro-inflammatory factors. A protection from inflammatory stress on intestinal porcine enterocytes cells (IPEC-J2) of 5-MT was observed through the stimulation of TLR4 pathway. Besides, 5-MT also exhibited robust anti-inflammatory effect in DSS-induced colitis mice with improving colitis symptoms, barrier function and gut microbiota, which was same as presented by ASP-Ag-AP. In conclusion, ASP-Ag-AP could be a promising agent for colitis prevention and 5-MT could be the signal metabolite of ASP-Ag-AP on defending against intestinal inflammatory stress.