Microbiote et probiotiques : impact en santé humaine

Coudeyras, Sophie; Forestier, Christiane

doi:10.1139/w10-052

Cited by 15 publications

(12 citation statements)

References 239 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…Our data are at least in part supported by our previous study indicating that bifidobacteria were also less abundant in the ilea of naive conventionally colonized NOD2 –/– mice (IL-10 +/+ ), whereas distal small intestinal lactobacilli loads were even slightly higher as compared to WT controls [29]. Particularly bifidobacterial species constitute beneficial, “probiotic” microbes with anti-inflammatory properties that are also involved in conferring host resistance against pathogens [51]. It is, however, questionable, whether the observed minor changes in intestinal lactobacilli loads would have a biologically relevant impact.…”

Section: Discussionsupporting

confidence: 85%

Microbiota composition and immune responses during Campylobacter jejuni infection in conventionally colonized IL-10−/− mice lacking nucleotide oligomerization domain 2

Heimesaat

Grundmann

Alutis

et al. 2017

EuJMI

View full text Add to dashboard Cite

Host immune responses are pivotal for combating enteropathogenic infections. We here assessed the impact of the innate receptor nucleotide oligomerization domain protein 2 (NOD2) in murine Campylobacter jejuni-infection. Conventionally colonized IL-10–/– mice lacking NOD2 and IL-10–/– controls were perorally challenged with C. jejuni strain 81-176 and displayed comparable pathogenic colonization of intestines until day 14 postinfection (p.i.). Whereas overall intestinal microbiota compositions were comparable in naive mice, NOD2–/– IL-10–/– mice exhibited less fecal bifidobacteria and lactobacilli than IL-10–/– counterparts after infection. Interestingly, NOD2–/– IL-10–/– mice were clinically more compromised during the early phase of infection, whereas, conversely, IL-10–/– animals exhibited more frequently bloody feces lateron. While colonic apoptotic cell and T lymphocyte numbers were comparable in either C. jejuni-infected mice, B lymphocytes were lower in the colon of infected NOD2–/– IL-10–/– mice versus controls. At day 14 p.i., colonic TNF and IL-23p19 mRNA levels were upregulated in NOD2–/– IL-10–/– mice only. Translocation rates of intestinal commensals to mesenteric lymphnodes and extra-intestinal compartments including liver and kidney were comparable, whereas viable bacteria were more frequently detected in spleens derived from IL-10–/– as compared to NOD2–/– IL-10–/– mice. In conclusion, NOD2 is involved during C. jejuni infection in conventionally colonized IL-10–/– mice in a time-dependent manner.

show abstract

Section: Discussionsupporting

confidence: 85%

Microbiota composition and immune responses during Campylobacter jejuni infection in conventionally colonized IL-10−/− mice lacking nucleotide oligomerization domain 2

Heimesaat

Grundmann

Alutis

et al. 2017

EuJMI

View full text Add to dashboard Cite

show abstract

“…Remarkably, the Bifidobacteria population was virtually absent in NOD2 -/- mice. Eventhough these differences might be rather subtle at the first glance, the biological impact might be significant in our parasitic infection model given that particularly Bifidobacteria are considered as beneficial, probiotic bacterial species with anti-inflammatory properties and, hence, contribute to host colonization resistance against invading pathogens [41]. This is further supported by a previous in vitro study, demonstrating that co-culture of Bifidobacteria stimulated dendritic cells with CD4+ T cells resulted in an increase of CD25+ FOXP3+ Tregs [42].…”

Section: Discussionsupporting

confidence: 53%

Nucleotide-Oligomerization-Domain-2 Affects Commensal Gut Microbiota Composition and Intracerebral Immunopathology in Acute Toxoplasma gondii Induced Murine Ileitis

et al. 2014

View full text Add to dashboard Cite

BackgroundWithin one week following peroral high dose infection with Toxoplasma (T.) gondii, susceptible mice develop non-selflimiting acute ileitis due to an underlying Th1-type immunopathology. The role of the innate immune receptor nucleotide-oligomerization-domain-2 (NOD2) in mediating potential extra-intestinal inflammatory sequelae including the brain, however, has not been investigated so far.Methodology/Principal FindingsFollowing peroral infection with 100 cysts of T. gondii strain ME49, NOD2-/- mice displayed more severe ileitis and higher small intestinal parasitic loads as compared to wildtype (WT) mice. However, systemic (i.e. splenic) levels of pro-inflammatory cytokines such as TNF-α and IFN-γ were lower in NOD2-/- mice versus WT controls at day 7 p.i. Given that the immunopathological outcome might be influenced by the intestinal microbiota composition, which is shaped by NOD2, we performed a quantitative survey of main intestinal bacterial groups by 16S rRNA analysis. Interestingly, Bifidobacteria were virtually absent in NOD2-/- but not WT mice, whereas differences in remaining bacterial species were rather subtle. Interestingly, more distinct intestinal inflammation was accompanied by higher bacterial translocation rates to extra-intestinal tissue sites such as liver, spleen, and kidneys in T. gondii infected NOD2-/- mice. Strikingly, intracerebral inflammatory foci could be observed as early as seven days following T. gondii infection irrespective of the genotype of animals, whereas NOD2-/- mice exhibited higher intracerebral parasitic loads, higher F4/80 positive macrophage and microglia numbers as well as higher IFN-γ mRNA expression levels as compared to WT control animals.Conclusion/SignificanceNOD2 signaling is involved in protection of mice from T. gondii induced acute ileitis. The parasite-induced Th1-type immunopathology at intestinal as well as extra-intestinal sites including the brain is modulated in a NOD2-dependent manner.

show abstract

“…Ileal loads of bifidobacteria, however, were more than two orders of magnitude lower following P. aeruginosa infection. As commensal residents with beneficial effects for intestinal homeostasis, bifidobacteria contribute to mucosal barrier functions directed against pathogenic colonization of the vertebrate host [33, 34]. Two bifidobacterial strains that were isolated from resident infant human gastrointestinal microbiota exerted antibacterial activity against several pathogens such as S. typhimurium, E. coli, Klebsiella pneumoniae, Yersinia pseudotuberculosis, Staphylococcus aureus and P. aeruginosa in vitro [34].…”

Section: Discussionmentioning

confidence: 99%

Acute ileitis facilitates infection with multidrug resistant Pseudomonas aeruginosa in human microbiota-associated mice

et al. 2017

View full text Add to dashboard Cite

BackgroundThe rising incidence of multidrug resistant (MDR) Gram-negative bacteria including Pseudomonas aeruginosa has become a serious issue in prevention of its spread particularly among hospitalized patients. It is, however, unclear whether distinct conditions such as acute intestinal inflammation facilitate P. aeruginosa infection of vertebrate hosts.Methods and resultsTo address this, we analysed P. aeruginosa infection in human microbiota-associated (hma) mice with acute ileitis induced by peroral Toxoplasma gondii challenge. When perorally infected with P. aeruginosa at day 3 post ileitis induction, hma mice displayed higher intestinal P. aeruginosa loads as compared to hma mice without ileitis. However, the overall intestinal microbiota composition was not disturbed by P. aeruginosa (except for lowered bifidobacterial populations), and the infection did not further enhance ileal immune cell responses. Pro-inflammatory cytokines including IFN-γ and IL-12p70 were similarly increased in ileum and mesenteric lymph nodes of P. aeruginosa infected and uninfected hma mice with ileitis. The anti-inflammatory cytokine IL-10 increased multifold upon ileitis induction, but interestingly more distinctly in P. aeruginosa infected as compared to uninfected controls. Immune responses were not restricted to the intestines as indicated by elevated pro-inflammatory cytokine levels in liver and kidney upon ileitis induction. However, except for hepatic TNF-α levels, P. aeruginosa infection did not result in more distinct pro-inflammatory cytokine secretion in liver and kidney of hma mice with ileitis. Whereas viable intestinal bacteria were more frequently detected in systemic compartments such as spleen and cardiac blood of P. aeruginosa infected than uninfected mice at day 7 following ileitis induction, P. aeruginosa infection did not exacerbate systemic pro-inflammatory sequelae, but resulted in lower IL-10 serum levels.ConclusionAcute intestinal inflammation facilitates infection of the vertebrate host with MDR bacteria including P. aeruginosa and might also pose particularly hospitalized patients at risk for acquisition. Since acute T. gondii induced inflammation might mask immunopathology caused by P. aeruginosa, a subacute or chronic inflammation model might be better suited to investigate the potential role of P. aeruginosa infection in the aggravation of intestinal disease.Electronic supplementary materialThe online version of this article (doi:10.1186/s13099-017-0154-4) contains supplementary material, which is available to authorized users.

show abstract

Microbiote et probiotiques : impact en santé humaine

Cited by 15 publications

References 239 publications

Microbiota composition and immune responses during Campylobacter jejuni infection in conventionally colonized IL-10−/− mice lacking nucleotide oligomerization domain 2

Microbiota composition and immune responses during Campylobacter jejuni infection in conventionally colonized IL-10−/− mice lacking nucleotide oligomerization domain 2

Nucleotide-Oligomerization-Domain-2 Affects Commensal Gut Microbiota Composition and Intracerebral Immunopathology in Acute Toxoplasma gondii Induced Murine Ileitis

Acute ileitis facilitates infection with multidrug resistant Pseudomonas aeruginosa in human microbiota-associated mice

Contact Info

Product

Resources

About