Metagenomic analysis of Tongxie Yaofang therapy for rat models of ulcerative colitis with liver depression and spleen deficiency syndrome

Tongxie Yaofang (TXYF) has therapeutic effect on the ulcerative colitis (UC) with liver depression and spleen deficiency syndrome. This study investigated the changes in the gut microbiota of UC rats treated with TXYF. Wistar rats were divided into three groups: Control, dinitrobenzene sulfonic acid (DNBS)-colitis, and DNBS + TXYF (n = 8 per group). UC model was constructed via intrarectally injection of DNBS (25 mg DNBS and 0.25 mL 50% ethanol); rats in DNBS + TXYF group were administered with TXYF (20.8 g/kg) for 21 days. Physiological parameters were measured. Five samples from each group were selected for metagenomic analysis. TXYF treatment significantly reduced disease activity index, colon mucosal damage index, and tumor necrosis factor-alpha level. TXYF treatment prevented DNBS-induced dysregulation of gut microbial communities. Compared with DNBS-colitis group, the abundance of Firmicutes increased significantly and that of Bacteroidetes and Proteobacteria decreased in DNBS + TXYF group. Pathways such as protein processing in the endoplasmic reticulum pathway was enriched in the DNBS-colitis group, whereas it was decreased in the DNBS + TXYF group. Thus, TXYF treatment could effectively restore the dysregulation of intestinal flora induced by UC.