Study shows association between gut microbes and brain structure in people with IBS

May 5, 2017 by Enrique Rivero

A new study by researchers at UCLA has revealed two key findings for people with irritable bowel syndrome about the relationship between the microorganisms that live in the gut and the brain.

For people with IBS research shows for the first time that there is an association between the gut microbiota and the brain regions involved in the processing of sensory information from their bodies. The results suggest that signals generated by the brain can influence the composition of microbes residing in the intestine and that the chemicals in the gut can shape the human brain's structure.

Additionally, the researchers gained insight into the connections among childhood trauma, brain development and the composition of the .

Previous studies performed in mice have demonstrated effects of gut microbiota on brain function and behavior, as well as the influence of the brain on the composition of microbes in the gut. However, to date, only one study performed in human subjects has confirmed the translatability of such findings to the human brain.

Studies have also reported evidence for alterations in the composition of gut microbiota in people with , but there has been little consistency among studies regarding the specific microbial alterations and the relationship of such alterations with the cardinal symptoms of IBS, recurring abdominal pain and altered bowel habits.

In relation to a person's history with childhood trauma, it has been shown to be associated with structural and functional brain changes; trauma in young children has also been shown to alter gut microbial composition. But how they are related has been unknown.

The UCLA researchers collected behavioral and clinical measures, stool samples and structural brain images from 29 adults diagnosed with IBS, and 23 healthy control subjects. They used DNA sequencing and various mathematical approaches to quantify composition, abundance and diversity of the gut microbiota. They also estimated the microbial gene content and gene products of the stool samples. Then the researchers cross-referenced these gut microbial measures with structural features of the brain.

Based on the composition of the microbes in the gut, the samples from those diagnosed with IBS clustered into two subgroups. One group was indistinguishable from the healthy control subjects, while the other differed. Those in the group with an altered gut microbiota had more history of early life trauma and longer duration of IBS symptoms.

The two groups also displayed differences in brain structure.

Analysis of a person's gut may become a routine screening test for people with IBS in clinical practice, and in the future, therapies such as certain diets and probiotics may become personalized based on an individual's gut microbial profile. At the same time, subgroups of people with IBS distinguished by brain and microbial signatures may show different responsiveness to brain-directed therapies such as mindfulness-based stress reduction, cognitive behavioral therapy and targeted drugs.

A history of early life trauma has been shown to be associated with structural and functional brain changes and to alter gut microbial . It is possible that the signals the gut and its microbes get from the brain of an individual with a history of may lead to lifelong changes in the gut microbiome. These alterations in the may feed back into sensory regions, altering the sensitivity to gut stimuli, a hallmark of people with IBS.

The study was published online in the peer-reviewed journal Microbiome.

Explore further: Magnetic brain stimulation causes weight loss by making gut bacteria healthier

More information: Jennifer S. Labus et al. Differences in gut microbial composition correlate with regional brain volumes in irritable bowel syndrome, Microbiome (2017). DOI: 10.1186/s40168-017-0260-z

Related Stories

Magnetic brain stimulation causes weight loss by making gut bacteria healthier

April 3, 2017
A new study finds that a noninvasive electromagnetic brain stimulation technique helps obese people lose weight, partly by changing the composition of their intestinal bacteria—the so-called gut microbiota. Results of the ...

Prolonged military-style training causes changes to intestinal bacteria, increases inflammation

May 5, 2017
A new study finds that long periods of physiological stress can change the composition of microorganisms residing in the intestines (intestinal microbiota), which could increase health risks in endurance athletes and military ...

Intestinal bacteria alter gut and brain function

March 1, 2017
Research from McMaster University has found that bacteria in the gut impacts both intestinal and behavioural symptoms in patients suffering from irritable bowel syndrome (IBS), a finding which could lead to new microbiota-directed ...

Can changes in the brain affect your microbiome?

October 29, 2015
The microbiome in your gut can affect your brain: More and more data have recently shown that. But can it go the other way? Can brain changes affect your gut microbiome? And if so, do these changes affect your health and ...

Research on gut bacteria may change the way we look at anxiety, depression, and behavioural disorders

October 21, 2016
If aliens were to examine a human, they would think we were just slavish organisms designed to feed microbes and carry them around. Our bodies contain 10 times more bacteria than cells, and there are an estimated 3.3 million ...

Recommended for you

After a half-century of attempts, psilocybin has finally been synthesized in the lab

August 16, 2017
A team of researchers at Friedrich Schiller University Jena has figured how out to make psilocybin, the chemical responsible for creating hallucinations in people who consume the mushrooms that produce it naturally. In their ...

Using barcodes to trace cell development

August 16, 2017
How do the multiple different cell types in the blood develop? Scientists have been pursuing this question for a long time. According to the classical model, different developmental lines branch out like in a tree. The tree ...

The unexpected role of a well-known gene in creating blood

August 16, 2017
One of the first organ systems to form and function in the embryo is the cardiovascular system: in fact, this developmental process starts so early that scientists still have many unresolved questions on the origin of the ...

Researchers unlock clues to how cells move through the body

August 16, 2017
During its 120-day cycle the circulatory system transports red blood cells and nutrients throughout the human body. This system helps keep the body in balance and fight against infections and diseases by filtering old or ...

Eating habits affect skin's protection against sun

August 15, 2017
Sunbathers may want to avoid midnight snacks before catching some rays.

Chewing gum rapid test for inflammation

August 15, 2017
Dental implants occasionally entail complications. Six to 15 percent of patients develop an inflammatory response in the years after receiving a dental implant. This is caused by bacteria destroying the soft tissue and the ...

0 comments

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.