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Scope: Ulcerative colitis (UC) is a common chronic recurrent inflammatory bowel disease. This study attempts to reveal the improvement mechanism of floral mushroom polysaccharide (FMPS) on UC from the perspective of coordinated interaction between intestinal microbes and intestinal helper T cell 17 (Th17)/regulatory T cell (Treg) balance., Methods and Results: Dextran sulfate sodium (DSS)-induced colitis mice model is used for the experiment. The results suggest that FMPS up-regulated the expression of occludin, ZO-1, and MUC2, and down-regulated the secretion of TNF-α, IL-1β, and IL-6 in colitis mice. Importantly, FMPS restores intestinal Th17/Treg balance. Meanwhile, FMPS can regulate intestinal microorganisms and improve the level of short-chain fatty acids (SCFAs) in colitis mice. Intestinal microbial depletion and fecal microbiota transplantation (FMT) experiments reveal that FMPS ameliorated UC is mediated by intestinal microbiome. Flow cytometry further proves that FMPS restores intestinal Th17/Treg balance in a microbial-dependent manner., Conclusion: These results indicate that FMPS has the potential to improve UC, and its mechanism depends on the restoration of Th17/Treg balance mediated by intestinal microorganisms. Therefore, it is suggested that FMPS dietary supplement can be potentially used to intervene UC., (© 2022 Wiley-VCH GmbH.)

Ulcerative colitis (UC) is a chronic inflammatory bowel disease of unknown etiology that affects the colon and rectum. It has evolved into a global burden due to the high incidence in developed countries and the highly-increased incidence in developing countries. Non-starch polysaccharides (NSPs) from natural resources, as a type of functional carbohydrates, have a significant therapeutic effect on UC because of their good anti-inflammatory and immunomodulatory activities. Based on the etiology and pathogenesis of UC, this review summarizes the intervention effects and mechanisms of NSPs in the prevention and treatment of UC. The results showed that NSPs can improve UC by protecting the intestinal mucosal barrier, regulating the immune response of the intestinal mucosa, and remodeling the intestinal flora and metabolites. These contents provide theoretical basis for the application of polysaccharides in the prevention and treatment of UC., (Copyright © 2022 Elsevier B.V. All rights reserved.)

The ameliorative effect of Dendrobium fimbriatum polysaccharide (cDFPW1) on ulcerative colitis (UC) was investigated using a dextran-sodium-sulfate-induced (DSS-induced) mouse model in the present study. The results showed that cDFPW1 effectively improved colitis in mice by ameliorating weight loss, disease activity index (DAI) and colonic pathological damage, and by protecting the intestinal barrier function integrity. Moreover, cDFPW1 modulated the composition and metabolism of intestinal microbiota through enhancing Romboutsia , Lactobacillus and Odoribacter , and reducing Parasutterella , Burkholderia-Caballeronia-Paraburkholderia and Acinetobacter in colitis mice. Notably, cDFPW1 significantly restored the homeostasis of Th17/regulatory T (Treg) cells and the expression of specific cytokines. Western blotting of colon tissues showed that cDFPW1 markedly up-regulated the expression of Nrf2 and inhibited the phosphorylation of NF-κB signaling. These results indicated that cDFPW1 possesses the potential of improving UC and its effect on palliating colitis may be connected with the regulation of Nrf2/NF-κB signaling.

Background: In gut microbiome studies, the cultured gut microbial resource plays essential roles, such as helping to unravel gut microbial functions and host-microbe interactions. Although several major studies have been performed to elucidate the cultured human gut microbiota, up to 70% of the Unified Human Gastrointestinal Genome species have not been cultured to date. Large-scale gut microbial isolation and identification as well as availability to the public are imperative for gut microbial studies and further characterizing human gut microbial functions., Results: In this study, we constructed a human Gut Microbial Biobank (hGMB; homepage: hgmb.nmdc.cn ) through the cultivation of 10,558 isolates from 31 sample mixtures of 239 fresh fecal samples from healthy Chinese volunteers, and deposited 1170 strains representing 400 different species in culture collections of the International Depository Authority for long-term preservation and public access worldwide. Following the rules of the International Code of Nomenclature of Prokaryotes, 102 new species were characterized and denominated, while 28 new genera and 3 new families were proposed. hGMB represented over 80% of the common and dominant human gut microbial genera and species characterized from global human gut 16S rRNA gene amplicon data (n = 11,647) and cultured 24 "most-wanted" and "medium priority" taxa proposed by the Human Microbiome Project. We in total sequenced 115 genomes representing 102 novel taxa and 13 previously known species. Further in silico analysis revealed that the newly sequenced hGMB genomes represented 22 previously uncultured species in the Unified Human Gastrointestinal Genome (UHGG) and contributed 24 representatives of potentially "dark taxa" that had not been discovered by UHGG. The nonredundant gene catalogs generated from the hGMB genomes covered over 50% of the functionally known genes (KEGG orthologs) in the largest global human gut gene catalogs and approximately 10% of the "most wanted" functionally unknown proteins in the FUnkFams database., Conclusions: A publicly accessible human Gut Microbial Biobank (hGMB) was established that contained 1170 strains and represents 400 human gut microbial species. hGMB expands the gut microbial resources and genomic repository by adding 102 novel species, 28 new genera, 3 new families, and 115 new genomes of human gut microbes. Video abstract.

Mice are widely used as experimental models for gut microbiome (GM) studies, yet the majority of mouse GM members remain uncharacterized. Here, we report the construction of a mouse gut microbial biobank (mGMB) that contains 126 species, represented by 244 strains that have been deposited in the China General Microorganism Culture Collection. We sequence and phenotypically characterize 77 potential new species and propose their nomenclatures. The mGMB includes 22 and 17 species that are significantly enriched in ob/ob and wild-type C57BL/6J mouse cecal samples, respectively. The genomes of the 126 species in the mGMB cover 52% of the metagenomic nonredundant gene catalog (sequence identity ≥ 60%) and represent 93-95% of the KEGG-Orthology-annotated functions of the sampled mouse GMs. The microbial and genome data assembled in the mGMB enlarges the taxonomic characterization of mouse GMs and represents a useful resource for studies of host-microbe interactions and of GM functions associated with host health and diseases.