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- Parsons, Bryony N., et al.
(författare)
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Dietary Supplementation with Soluble Plantain Non-Starch Polysaccharides Inhibits Intestinal Invasion of Salmonella Typhimurium in the Chicken
- 2014
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Ingår i: PLOS ONE. - : Public Library of Science. - 1932-6203. ; 9:2, s. 87658-
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Tidskriftsartikel (refereegranskat)abstract
- Soluble fibres (non-starch polysaccharides, NSP) from edible plants but particularly plantain banana (Musa spp.), have been shown in vitro and ex vivo to prevent various enteric pathogens from adhering to, or translocating across, the human intestinal epithelium, a property that we have termed contrabiotic. Here we report that dietary plantain fibre prevents invasion of the chicken intestinal mucosa by Salmonella. In vivo experiments were performed with chicks fed from hatch on a pellet diet containing soluble plantain NSP (0 to 200 mg/d) and orally infected with S. Typhimurium 4/74 at 8 d of age. Birds were sacrificed 3, 6 and 10 d post-infection. Bacteria were enumerated from liver, spleen and caecal contents. In vitro studies were performed using chicken caecal crypts and porcine intestinal epithelial cells infected with Salmonella enterica serovars following pre-treatment separately with soluble plantain NSP and acidic or neutral polysaccharide fractions of plantain NSP, each compared with saline vehicle. Bacterial adherence and invasion were assessed by gentamicin protection assay. In vivo dietary supplementation with plantain NSP 50 mg/d reduced invasion by S. Typhimurium, as reflected by viable bacterial counts from splenic tissue, by 98.9% (95% CI, 98.1-99.7; Pless than0.0001). In vitro studies confirmed that plantain NSP (5-10 mg/ml) inhibited adhesion of S. Typhimurium 4/74 to a porcine epithelial cell-line (73% mean inhibition (95% CI, 64-81); Pless than0.001) and to primary chick caecal crypts (82% mean inhibition (95% CI, 75-90); Pless than0.001). Adherence inhibition was shown to be mediated via an effect on the epithelial cells and Ussing chamber experiments with ex-vivo human ileal mucosa showed that this effect was associated with increased short circuit current but no change in electrical resistance. The inhibitory activity of plantain NSP lay mainly within the acidic/pectic (homogalacturonan-rich) component. Supplementation of chick feed with plantain NSP was well tolerated and shows promise as a simple approach for reducing invasive salmonellosis.
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| 2. |
- Roberts, Carol L, et al.
(författare)
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Translocation of Crohns disease Escherichia coli across M-cells: contrasting effects of soluble plant fibres and emulsifiers
- 2010
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Ingår i: GUT. - : BMJ Publishing Group. - 0017-5749. ; 59:10, s. 1331-1339
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Tidskriftsartikel (refereegranskat)abstract
- Background Crohns disease is common in developed nations where the typical diet is low in fibre and high in processed food. Primary lesions overlie Peyers patches and colonic lymphoid follicles where bacterial invasion through M-cells occurs. We have assessed the effect of soluble non-starch polysaccharide (NSP) and food emulsifiers on translocation of Escherichia coli across M-cells. Methods To assess effects of soluble plant fibres and food emulsifiers on translocation of mucosa-associated E coli isolates from Crohns disease patients and from non-Crohns controls, we used M-cell monolayers, generated by co-culture of Caco2-cl1 and Raji B cells, and human Peyers patches mounted in Ussing chambers. Results E coli translocation increased across M-cells compared to parent Caco2-cl1 monocultures; 15.8-fold (IQR 6.2-32.0) for Crohns disease E coli (N=8) and 6.7-fold (IQR 3.7-21.0) for control isolates (N=5). Electronmicroscopy confirmed E coli within M-cells. Plantain and broccoli NSP markedly reduced E coli translocation across M-cells at 5 mg/ml (range 45.3-82.6% inhibition, pandlt;0.01); apple and leek NSP had no significant effect. Polysorbate-80, 0.01% vol/vol, increased E coli translocation through Caco2-cl1 monolayers 59-fold (pandlt;0.05) and, at higher concentrations, increased translocation across M-cells. Similarly, E coli translocation across human Peyers patches was reduced 45+/-7% by soluble plantain NSP (5 mg/ml) and increased 2-fold by polysorbate-80 (0.1% vol/vol). Conclusions Translocation of E coli across M-cells is reduced by soluble plant fibres, particularly plantain and broccoli, but increased by the emulsifier Polysorbate-80. These effects occur at relevant concentrations and may contribute to the impact of dietary factors on Crohns disease pathogenesis.
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