Video report of the presentation given by Prof. Jonathan Rhodes, University of Liverpool, United Kingdom, at the Falk Symposium 192 " IBD 2014: Thinking out of the Box" in Paris, May 30 - 31, 2014.
© Falk Foundation e.V., Freiburg. All rights reserved.
There is no doubt whatsoever that changes to intestinal microbiota play a fundamental role in inflammatory bowel disease. This is supported by numerous studies showing altered fecal and mucosa-associated microbiota and also by case histories such as that of a 14-year-old patient with Crohn’s disease whose microbiome profile normalised after reaching clinical remission by enteral nutrition.
The pathological mechanisms of Crohn’s disease and ulcerative colitis are probably different. It seems, for example, that in the case of Crohn’s disease, genetic (or environmental) changes may cause a defect in the innate immune system which allows bacteria, and E. coli in particular, to invade the intestinal wall more easily. In ulcerative colitis, however, environmental factors seem to play an even greater role, modulating interactions between bacterial components and the colonic surface epithelium.
In theory there are several approaches we can take to normalising disturbed gut microbiota. However, treatment trials involving prebiotics, plant fibres that promote the growth of probiotic bacteria in the bowel, have so far been disappointing. Results achieved using genetically modified bacteria as probiotics may hold more promise, and they may also prove to be of value for maintaining remission in ulcerative colitis patients. “Contrabiotics”, i.e. soluble plant fibres that prevent interaction between bacteria and the intestinal wall, are virtually untested in humans to date. A diet high in fruit fibre does, however, appear to halve the risk of developing Crohn’s disease. Finally, the precise mechanism of action of enteral nutrition is still unclear and needs further study.