RESUMEN
BACKGROUND: Ulcerative colitis (UC) is considered to be closely associated with alteration of intestinal microorganisms. According to the traditional Chinese medicine (TCM) theory, UC can be divided into two disease syndromes called Pi-Xu-Shi-Yun (PXSY) and Da-Chang-Shi-Re (DCSR). The relationships among gut microbiota, TCM syndromes, and UC pathogenesis have not been well investigated. AIM: To investigate the role of gut microbiota in UC and the distinction of microbiota dysbiosis between PXSY and DCSR syndromes. METHODS: From May 2015 to February 2016, UC patients presenting to LongHua Hospital who met the established inclusion and exclusion criteria were enrolled in this retrospective study. Fresh stool specimens of UC patients with PXSY or DCSR were collected. The feces of the control group came from the health examination population of Longhua Hospital. The composition of gut bacterial communities in stool samples was determined by the pyrosequencing of 16S ribosomal RNA. The high-throughput sequencing reads were processed with QIIME, and biological functions were predicted using Phylogenetic Investigation of Communities by Reconstruction of Unobserved States. RESULTS: The composition of gut bacterial communities in 93 stool samples (30 healthy controls, 32 patients with PXSY syndrome, and 31 patients with DCSR syndrome) was determined by the pyrosequencing of 16S ribosomal RNA. Beta diversity showed that the composition of the microbiota was different among the three groups. At the family level, Porphyromonadaceae, Rikeneliaceae, and Lachnospiraceae significantly decreased while Enterococcus, Streptococcus, and other potential pathogens significantly increased in UC patients compared to healthy subjects. At the genus level, Parabacteroides, Dorea, and Ruminococcus decreased while Faeca-libacterium showed increased abundance in UC compared to healthy controls. Five differential taxa were identified between PXSY and DCSR syndromes. At the genus level, a significantly increased abundance of Streptococcus was observed in DCSR patients, while Lachnoclostridium increased in PXSY patients. The differential functional pathways of the gut microbiome between the PXSY and DCSR groups mainly included lipid metabolism, immunity, and the metabolism of polypeptides. CONCLUSION: Our study suggests that the gut microbiota contributes to the distinction between the two TCM syndromes of UC.