AUTHOR=Liu Jinglong , Lin Hao , Cao Man , Lin Tan , Lin Aiqiang , Xu Wei , Wang Han , He Jianquan , Li Yuantao , Tang Hailing , Zhang Bangzhou 

TITLE=Shifts and importance of viable bacteria in treatment of DSS-induced ulcerative colitis mice with FMT

JOURNAL=Frontiers in Cellular and Infection Microbiology

VOLUME=Volume 13 - 2023

YEAR=2023

URL=https://www.frontiersin.org/journals/cellular-and-infection-microbiology/articles/10.3389/fcimb.2023.1124256

DOI=10.3389/fcimb.2023.1124256

ISSN=2235-2988

ABSTRACT=Ulcerative colitis (UC) has become a global public health concern, and is in urgent need of novel therapies. Fecal microbiota transplantation (FMT) targeting gut microbiota has recently been applied to the treatment of UC. Despite its recent successes, it is still largely unknown how FMT functionally modulates the gut microbiota and improves the disease. In this paper, we presented a pioneer work to evaluate the importance and communities of viable gut microbiota in UC mice. We prospectively collected fecal samples from the 40 mice (30 mice for dextran sulfate sodium (DSS)-induced, 10 for controls), followed by Propidium monoazide treatment for 16S rRNA gene sequencing. These 30 mice were divided equally into 3 groups, which were transplanted with original donor microbiota (DO), inactivated donor microbiota (DI) and saline, respectively. We demonstrated that the community structure of viable bacteria was significantly different from fecal bacteria based on total DNA. Furthermore, the intestinal viable microbiota and colonic mucosal structure of mice were significantly changed by DSS induction. The histological analysis showed that only the mice treated with original donor microbiota group (HF) achieved a significant improvement. Compared with inactivated donor microbiota group (IF) and saline (NF), Lactobacillus and Halomonas were significantly enriched in the HF group. Cumulatively, we inferred that only live bacteria from human donor reversed the histopathology and symptoms of UC in mice and altered the gut microbiota. Therefore, this study implies that the activity of gut microbiota in donor samples should be considered in FMT and that detailed analysis of viable microbiota is essential to understand the mechanisms by which FMT produces therapeutic effects in the future.