A POTENTIAL link has been discerned between gut bacteria and behaviour in patients with irritable bowel syndrome (IBS), a common gastrointestinal disorder with an approximate worldwide incidence of 11%. It is hoped that the findings from this study will assist in the development of new treatments; to date, treatment options have primarily been focussed on symptomatic relief rather than cure. Currently, treatment options are based on medication, including laxatives and antispasmodics, and changes in diet; however, because the causes of IBS are unknown, the effectiveness of these existing treatments is limited.
Previous research has revealed that patients with IBS display changes in their gut microbiota, yet the relevance of this change is undetermined. This study aimed to investigate the role of gut microbiota in IBS and the potential effect this flora may have on gut and brain function. Faecal transplants were used to transfer microbiota from three groups of individuals into germ-free mice. The first group were healthy volunteers who did not have IBS, the second group had IBS, but not anxiety, and the final group had both IBS and anxiety. Gut function and behaviour in the mice was then studied.
Following the faecal transplant, the researchers found that the mice who received a faecal transplant from the group without IBS displayed no difference in gut function and behaviour. In contrast, the mice who received faecal microbiota from patients with IBS were found to display anxiety-like behaviour, faster gastrointestinal transit, intestinal barrier dysfunction, and innate immune activation.
Speaking about the importance of these findings, the study’s first author Dr Giada De Palma, Farncombe Family Digestive Health Research Institute, Hamilton, Canada, commented: “This is a landmark study because it moves the field beyond a simple association, and towards evidence that changes in the microbiota impact both intestinal and behavioural responses in IBS.” It is hoped that the results will provide a stepping stone towards the development of microbiota-based therapies for IBS. Additionally, the authors noted that this study adds to the body of evidence that gut microbiota can influence the brain and a range of mental health conditions. Further research studies are required to fully ascertain the connection.