The study, reported in the BMJ journal Gut, suggests translocation of Escherichia coli in gut mucosal M-cells is reduced by plantain and broccoli soluble fibers, but increased by the emulsifier Polysorbate-80.
“This implies that dietary supplementation with such fibers might have a protective effect against Crohn’s disease relapse by preventing bacterial invasion of the mucosa,” wrote the researchers, led by Dr. Barry Campbell and Dr Jonathan Rhodes, both from the University of Liverpool.
Low fiber link?
Crohn’s disease is an inflammatory disease that can affect any part of the gastrointestinal tract, causing a wide variety of symptoms including abdominal pain, diarrhea, vomiting, and weight loss.
Crohn’s disease is common in developed nations where the typical diet is low in fiber and high in processed food. Its incidence has been rising, with diet believed to be linked to higher prevalence in industrialized countries.
Increased numbers of E coli have been found in association with Crohn’s mucosa by previous research. A bacterial invasion of gut epithelium cells is known to occur initially through specialized microfold epithelial cells (M-cells).
Researchers reported that parts of the world - like as Africa, India and Central America - where plantains form an important part of the staple diet have low rates for inflammatory bowel disease such as Crohn’s disease.
The new study aimed to assesses the effects of soluble plant fibers and food emulsifiers on translocation of Escherichia coli across M-cells in Crohn’s disease and from non-Crohn’s patients.
The effects of non-starch polysaccharide (NSP) plant fibers from plantain, broccoli, apple and leek were assessed and compared with the effects of food emulsifiers Polysorbate-80 and Polysorbate-60 - commonly used in the food industry.
The study reports plantain and broccoli NSP distinctly reduced E coli translocation across M-cells, whereas apple and leek NSP had no significant effects.
“Plantain NSP was shown to significantly block translocation of Crohn’s disease E coli through M-cells, both at 5 and 50 mg/mL. Likewise, broccoli NSP significantly inhibited bacterial translocation across M-cells in a dose-dependent manner,” reported the researchers
At high concentrations Polysorbate-80 was seen to increase E coli translocation across M-cells.
Similarly, E coli translocation across human Peyer’s patches was reduced by over 4,500 percent by soluble plantain NSP, whereas translocation was doubled with polysorbate-80 emulsions.
“Soluble plant fibers, particularly those present in plantain and broccoli, are shown to inhibit translocation of Crohn’s mucosa associated E coli isolates across M-cells, at concentrations that should be readily achievable in vivo,” wrote the researchers.
The researchers suggest the effects of food emulsifiers on E coli translocation could offer potential explanations for the association between the modern ‘Western’ diet and Crohn’s disease.
“Different dietary components may have powerful and contrasting effects on bacterial translocation across intestinal M-cells. These effects may be relevant to the role of environmental factors in the pathogenesis of Crohn’s disease and suggest possible novel therapeutic approaches
“These effects occur at relevant concentrations and may contribute to the impact of dietary factors on Crohn’s disease pathogenesis,” reported the authors
Intervention studies are needed to assess the effects of dietary changes in soluble plant fiber and emulsifier intake on Crohn’s disease activity, conclude the researchers.
Published online ahead of print, doi: 10.1136/gut.2009.195370
“Translocation of Crohn’s disease Escherichia coli across M-cells: contrasting effects of soluble plant fibres and emulsifiers”
Authors: C.L Roberts, A.V Keita, S.H Duncan, N. O’Kennedy, J.D Soderholm, J.M Rhodes, B.J Campbell