Sequencing analysis of gut microbiota (16s rRNA) revealed two distinct IBS subgroups, one
A new study by UCLA researchers has revealed two key findings for people with irritable bowel syndrome (IBS) about the relationship between the microorganisms that live in their gut and their brains. The research has discovered 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 gut microbiome.
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.
A history of early-life trauma has been shown to be associated with structural and functional brain changes and to alter gut microbial composition. It is possible that the signals the gut and its microbes receive from the brain of an individual with a history of childhood trauma may lead to lifelong changes in the gut microbiome.
“Differences in Gut Microbial Composition Correlate with Regional Brain Volumes in Irritable Bowel Syndrome,” Microbiome, May 1, 2017