Scientists May Have Discovered Irritable Bowel Syndrome Cause in Mice

Scientists from McMaster University and Canada have found a direct link between gut-brain communication and irritable bowel syndrome (IBS). 

The study, published in the journal Translational Medicine, observed how germ-free mice receiving fecal microbiota from patients with irritable bowel syndrome mimicked IBS symptoms such as anxiety.

Premysl Bercik and colleagues from the university collected stool samples from patients with history of IBS and diarrhea for at least two years, as well as from five individuals for control, in order to test the guts of the germ-free mice. 

After three weeks, the researchers assessed the gut microbiota of the rodents and compared the bacterial profiles to those that were from the fecal samples of the individuals.

According to Science Daily, results showed startling differences between the bacteria that appeared in the germ-free mice weeks after they received it from the patients that were diagnosed with IBS. 

In the experiment's second phase, they tried to check if anxiety-like behaviors linked to IBS was transferred along with the gut microbes.

Interestingly, mice with IBS bacteria that didn't have anxiety symptoms didn't show the same behavior. However, mice with gut bacteria from patients with IBS and the same anxiety-like symptoms also showed the same behavior.

Sarkis Mazmanian, a professor at Caltech who was involved in the work, wrote to The Scientist that this is an interesting discovery, as it demonstrates the functionality of how bacteria from irritable bowel syndrome can actually induce gastrointestinal issues and anxiety associated with the syndrome.

However, this is also not too surprising for others, as it has been known for a time that different populations of microbes from mice can have different effects on the anxiety of the said animal.

Unfortunately, this study was not able to exactly identify the bacteria that was observed, and thus could not exactly determine if these bacteria can be directly involved in the behavior of IBS in humans.