Novel strains of Bacteroides fragilis and Bacteroides ovatus alleviate the LPS-induced inflammation in mice

Appl Microbiol Biotechnol. 2019 Mar;103(5):2353-2365. doi: 10.1007/s00253-019-09617-1. Epub 2019 Jan 21.

Abstract

Lipopolysaccharide (LPS) can promote the expression of pro-inflammatory cytokines, damage the tight junction of epithelial walls, and thereby lead to chronic low-grade intestinal inflammatory disorders. Evidences of many beneficial functions from Bacteroides strains suggest their intervention capabilities in LPS-induced inflammation. In the present study, both healthy and LPS-treated mice were consistently treated with Bacteroides strains for 5 days. The intestinal microbiota alteration, epithelial permeability, cytokine expression, and autoimmune and innate immune responses were analyzed. B. fragilis HCK-B3 and B. ovatus ELH-B2 from our laboratory collection were demonstrated to assist intestinal equilibrium by maintaining the diversity of gut microbiota and relieve LPS-induced inflammation by either modulating cytokine production or restoring the Treg/Th-17 balance. Our research indicated that the Bacteroides strains with capabilities of alleviating inflammation have the potential as therapeutics to prevent intestinal inflammatory disorders and provided scientific supports for discovering next-generation probiotics.

Keywords: Bacteroides; Inflammation; Lipopolysaccharide; Next-generation probiotics; Regulatory T cells.

MeSH terms

  • Animals
  • Bacteroides fragilis / classification
  • Bacteroides fragilis / immunology*
  • Bacteroides fragilis / metabolism*
  • Cytokines / biosynthesis
  • Cytokines / immunology
  • Female
  • Gastrointestinal Microbiome / drug effects
  • Inflammation / therapy
  • Lipopolysaccharides / toxicity
  • Mice
  • Mice, Inbred C57BL
  • Probiotics / metabolism*
  • T-Lymphocytes, Regulatory / immunology*
  • Th17 Cells / immunology*

Substances

  • Cytokines
  • Lipopolysaccharides