Indigenous microbes and their soluble factors differentially modulate intestinal glycosylation steps in vivo

Abstract

It has been shown that Bacteroides thetaiotaomicron, a representative member of the gut microflora, signals intestinal epithelial cells both in vivo and in vitro and modulate specific glycosylation processes that may mediate intestinal functions. However it is not known whether these modulations depend on the presence of live bacteria or may be elicited by soluble factors produced in vitro by this bacterium. We used lectins and an histochemical approach to survey tissue sections prepared from various cellular compartments of the small and large intestine of NRMI/KI mice grown under gnotobiotic conditions. We compared the results obtained with bacterial culture supernatant and live B. thetaiotaomicron to those obtained from germ-free mice or mice having a conventional microflora. This approach allowed us to conclude that (1) a small but specific number of glycan patterns were restored after treatment with bacterial culture supernatant and (2) the B. thetaiotaomicron associated mice restored a larger number of patterns, however, the complete conventional mice pattern must be a function of the whole microflora in the gut. The possibility to modulate this complex glycosylation pattern by introducing exogenous bacteria and bacterial products should be considered as a promising approach towards understanding the molecular basis of microbial-host interactions.

Effects of in Ovo Infusion of Probiotic Strains on Performance Parameters, Jejunal Bacterial Population and Mucin Gene Expression in Broiler Chicken

“…The gut mucin amount and composition are arranged based on bacterial glucodisase, activities responsible for removal of monosaccharide residues from mucin carbohydrate side chains (Hoskins et al, 1985), as well as via regulation of intestinal glycosylation (Bry et al, 1996;Bryk et al, 1999;Freitas et al, 2005;Sharma & Schumacher, 1995). An increased mucin synthesis and secretion have been shown to occur with probiotics consisting mainly of Lactobacillus and Bifidobacterium (Mack, 1999;Mack 2003).…”

Modulation of intestinal mucin composition and mucosal morphology by dietary phytogenic inclusion level in broilers

“…Furthermore the changes in mucin monosaccharide composition pattern as in Gal, Fuc and GalNac molar ratios need to be further assessed in terms of overall gut microbial ecology, as it is known that a correlation between mucin composition and bacterial colonization and proliferation exits. The latter is evidenced via the degradation of mucin by bacterial glycosidases (Hoskins et al, 1986;Ruas-Madiedo et al, 2008), the bacterial utilization of mucin carbohydrate side chains as energy source (Salyers, 1979;Scwad and Gä nzle, 2011;Stahl et al, 2011) and the bacterial adhesion in mucin monosaccharide (Kirjavainen et al, 1998;Gusils et al, 2003), as well as the ability of gut microflora to modulate intestinal glycosylation (Bry et al, 1996;Gheri Bryk et al, 1999;Freitas et al, 2005) and mucin gene expression (Mack et al, 1999 and. Therefore, this correlation may determine to a significant extent which species or even strains within species are best suited for utilization, colonization and/or adhesion to intestinal mucus.…”

“…Mucin monosaccharide composition depends on a dynamic interaction between adhesion of intestinal bacteria (Kirjavainen et al, 1998;Ouwehand et al, 1999;Gusils et al, 2003), host intestinal glycosylation (Bry et al, 1996;Gheri Bryk et al, 1999;Freitas et al, 2005) and microbial degradation by the intestinal microflora (Hoskins et al, 1986;Ruas-Madiedo et al, 2008).…”

The histochemistry and cell biology vade mecum: a review of 2005–2006

“…Freitas et al (2005) have applied genetically identical germ-free mice to study the inXuence of Bacteroides thetaiotaomicron. It is not known whether the modulation of glycoconjugates is dependent upon on the presence of live bacteria or may be elicited by soluble factors produced by this bacterium.…”