New gut insight for irritable bowel syndrome sufferers

Are you suffering from the nagging irritable bowel syndrome (IBS) and cannot enjoy your food? Here is good news.

Researcher have found that muscular lining of the intestine contains macrophage - an immune system cell - that regulates the contractions of the colon to push digested material through the digestive tract.

The interactions between macrophage and nerve cells are orchestrated by the "good" bacteria in the intestine that aids in healthy digestion.

A potential cause of IBS is a change in the bacterial environment in the intestine.

"By better understanding how the nervous system cells, the muscularis macrophages and signals from inside the intestine interact, we may be able to find new treatments for IBS or even prevent it," said Milena Bogunovic, an assistant professor of microbiology at Penn State College of Medicine.

To dig further, researchers developed a method to deplete muscularis macrophages in the intestines of mice to determine their function.

"After macrophage depletion, we observed that the normal intestinal movements went irregular, suggesting that intestinal movements are regulated by macrophages," Bogunovic explained.

Next, researchers looked for how the regulation happens.

They found that with "good bacteria", nerve cells and macrophages help each other to carry one key function - to regulate the physiology of the gut.

By giving mice antibiotics to kill off the "good" bacteria, they found the communication between macrophages and neurons was interrupted.

"By restoring the 'good' bacteria in the mice, the miscommunication between macrophages and neurons is reversed. It shows that the dialogue between the macrophages and nervous system is adaptable to the changes in the bacterial environment," Bogunovic concluded in the journal Cell.