A new study has revealed that high levels of a hormone found in gut cells may contribute to many cases of chronic diarrhea. The findings help explain up to 40% of cases of irritable bowel syndrome (IBS) in patients who experience diarrhea as a primary symptom, and they may pave the way for the development of a blood test and new treatment options.
The research was conducted by scientists at the University of Cambridge in the UK and published in the journal Gut on July 23. It was also reported on the EurekAlert website.
When we eat, the liver releases bile acid to break down fats so they can be absorbed by the body. Bile is secreted in the upper part of the small intestine and then reabsorbed in the lower part.
Roughly 1 in 100 people suffer from a condition called bile acid diarrhea (also known as bile acid malabsorption), where bile isn’t reabsorbed properly and instead travels to the large intestine (colon). There, it can cause urgent, watery diarrhea and increase the risk of fecal incontinence.
Diagnosing bile acid diarrhea is difficult because there’s currently no standard blood test for it in clinical practice. Many individuals are instead diagnosed with IBS—a general term for a range of digestive disorders.
It’s estimated that 1 in 20 people has IBS, and among them, about 1 in 3 who experience diarrhea as the main symptom may actually have undiagnosed bile acid diarrhea.
The Role of Insulin-Like Peptide 5 (INSL5)
Previous studies on mice have suggested that a gut hormone called insulin-like peptide 5 (INSL5)—found in cells located in the lower part of the colon and rectum—may play a role in chronic diarrhea. These cells release the hormone when irritated by bile acid.
Researchers wanted to investigate whether this hormone could also be responsible for chronic diarrhea in humans. This became possible thanks to a new antibody-based test developed by Eli Lilly, a pharmaceutical company collaborating with the research team. The test can detect trace amounts of INSL5 in blood samples.
A prior study conducted at the University of Adelaide in Australia explored how the gut hormone GLP-1—the target of many weight-loss medications—is triggered. Healthy volunteers received rectal bile acid enemas, which stimulated GLP-1 release but also caused unexpected diarrhea. When researchers analyzed samples from that study, they found that the bile acid enemas also caused a temporary spike in INSL5 levels. The higher the hormone levels, the more urgently participants needed to use the restroom.
These findings suggest that INSL5 may play a key role in chronic diarrhea. When the Cambridge team analyzed samples from patients with bile acid diarrhea, they found that INSL5 levels were nearly undetectable in healthy individuals, but significantly higher in patients. Moreover, the higher the INSL5 levels, the more watery the stool.
Dr. Chris Bannon, co-author of the study from the University of Cambridge, said:
“This was an extremely exciting finding because it shows us that this hormone may play a significant role in the symptoms of a misunderstood condition. It also suggests we might be able to develop a blood test to help diagnose bile acid diarrhea—if high levels of INSL5 are found only in affected individuals.”
Support Dawat Media Center
If there were ever a time to join us, it is now. Every contribution, however big or small, powers our journalism and sustains our future. Support the Dawat Media Center from as little as $/€10 – it only takes a minute. If you can, please consider supporting us with a regular amount each month. Thank you
DNB Bank AC # 0530 2294668
Account for international payments: NO15 0530 2294 668
Vipps: #557320
Support Dawat Media Center
If there were ever a time to join us, it is now. Every contribution, however big or small, powers our journalism and sustains our future. Support the Dawat Media Center from as little as $/€10 – it only takes a minute. If you can, please consider supporting us with a regular amount each month. Thank you
DNB Bank AC # 0530 2294668
Account for international payments: NO15 0530 2294 668
Vipps: #557320
Comments are closed.