Inflammatory bowel disease
Changing your diet is part of treating inflammatory bowel diseases such as Crohn’s disease and ulcerative colitis. Researchers are now tracking certain changes in the gut microbiome and the metabolic products they produce are probably an important part of remission.
Inflammatory bowel disease (IBD) is a chronic inflammatory disease of the gastrointestinal tract. Ulcerative colitis and Crohn’s disease are the two main types of IBD. Ulcerative colitis affects the large and rectum, whereas Crohn’s disease can occur in any part of the intestine. These painful and debilitating conditions affect one in 250 Australians aged 5 to 40.
Although the effect of nutrition on IBD remains poorly understood, diets that cause inflammatory changes in the gut microbiota have been associated with the development of IBD. The researchers investigated a further link between gut microbiota, diet and IBD in dogs that develop bowel disease similar to Crohn’s disease.
Using a special diet fed to 29 dogs with intestinal diseases, the research team tracked the fingerprints of the intestinal microbiome and metabolic products from fecal samples before and after the study.
Just over two-thirds of the dogs responded well to the diet and went into remission from the inflammatory disease. These dogs also showed a more metabolic product called secondary bile acids. These bile acids are associated with remission of IBD-like conditions in other animal models.
The bacterium Clostridium hiranonis is a major producer of secondary bile acids, and levels of this bacterium have been elevated in dogs that have gone into remission.
The same dogs that went into remission had fewer harmful bacteria such as Escherichia coli and Clostridium perfringens. The cultivation of these bacteria in the presence of secondary bile acids delayed their growth, indicating a probable path of their beneficial role.
In the final part of the study, the researchers looked at children with Crohn’s disease who went into remission after being fed a specialized liquid diet. These children had more Clostridium scinden bacteria, which are known producers of secondary bile acids.
This work opens up a new field of research for IBD – and in particular Crohn’s disease – for targeting the gut microbiota through specialized diets that will help suppress inflammation and potentially translate the disease into remission.
For reference: Wang S et al. Remission caused by diet in chronic enteropathy is associated with changes in the structure of the microbial community and the synthesis of secondary bile acids. Microbiome 2019; 7: 126.