Vegetable fibres could help in fight against Crohn's disease
27 August 2010
Researchers from the University of Liverpool are working with biotechnology company Provexis to test whether a new plantain-based food product could be used to treat patients with the disease.
Crohn's is a condition that affects one in 800 people in the UK and causes chronic intestinal inflammation, leading to pain, bleeding and diarrhoea, but the exact causes of the disease are still unknown. Bacteria in the gut have long been suspected as playing an important role and scientists have previously shown that people with Crohn's have higher numbers of the bacteria E.coli in their gut than healthy individuals.
University of Liverpool Professor, Jon Rhodes, part of the Liverpool Biomedical Research Centre (BRC), explains: "Crohn's disease affects people from all over the world, but it is much more prevalent in developed countries, where a diet of low fibre and processed foods is common. There has been a rapid increase in incidence of the disease in Japan, for example, which now has more of a western processed food diet. Dietary factors and the increased numbers of E.coli in the intestines of patients with Crohn's suggested to us that there could be a link between the food that we eat and the transportation of bacteria in the body".
Notably, people with Crohn's have more of a particular strain of E.coli that sticks to the gut wall more than others. The 'sticky' E.coli are capable of penetrating the gut wall via specialised cells called M cells. It is thought that this triggers an immune reaction and chronic inflammation, which causes the symptoms that are associated with Crohn's disease.
The Liverpool team investigated whether selected dietary agents could influence the ability of these ‘sticky’ E.coli to penetrate M cells.
In cell culture experiments, the researchers found that soluble fibres from broccoli and plantain (a type of large banana) prevented E.coli from getting into M cells. In contrast, a common stabiliser added to processed foods known as polysorbate-80 encouraged the movement of bacteria through the cells. This latter finding could offer a potential explanation for the association between Crohn's disease and the 'Western' diet.
Scientists are now conducting clinical trials to test whether a medical food containing plantain fibres could keep Crohn's patients in remission.
Dr Barry Campbell, from the University's Institute of Translational Medicine, added: "This research shows that different dietary components can have powerful effects on the movement of bacteria through the bowel. We have known for some time the general health benefits of eating plantain and broccoli, which are both high in vitamins and minerals, but until now we have not understood how they can boost the body's natural defences against infection common in Crohn's patients. Our work suggests that it might be important for patients with this condition to eat healthily and limit their intake of processed foods."
Peter Laing, Head of Research and Development at Provexis, said: "We are hopeful that this new medical food, containing soluble plantain fibres, could help halt the progression of the disease and prevent it from returning."
The research, funded by the Wellcome Trust and the National Institute for Health Research, is published this week in the journal 'Gut'.
Image: Broccoli; churl on Flickr
Reference
Roberts C et al. Translocation of Crohn's disease in Escherichia coli across M-cells: contrasting effects of soluble plant fibres and emulsifiers. Gut 2010.
