The gut microbiome – the trillions of bacteria and other microorganisms that live in the gastrointestinal tract – drive essential processes that protect the colon from tissue damage, according to a study co-led by researchers at Cedars-Sinai University of Health Sciences.
This discovery is cell, This has important implications for understanding how various intestinal diseases develop.
“Our research opens the door to therapies that focus on restoring critical molecular signals in vulnerable regions of the colon,” said Ofir Klein, MD, executive director of Cedars-Sinai Guerin Children’s Hospital, associate director of child health, and David Kaplan and Meredith Kaplan Distinguished Chair in Child Health. Klein is the study’s senior author.
Previous studies have shown that the four sections of the colon (ascending, transverse, descending, and sigmoid) have different functions and disease risks, but it was not clear why these differences exist.
In this study, the researchers showed that the identity of different regions of the colon is regulated by the gut microbiome. They identified that nicotinic acid, a molecule produced by specific bacteria within the gut microbiome, was the main driver of these regional differences in sections of the colon. Nicotinic acid, also known as niacin, which is part of the vitamin B3 family, helps the body convert food into energy and supports cellular health.
The researchers compared lab mice with and without microbiomes. They found that the production of nicotinic acid by bacteria in the upper colon activates protective mechanisms in colon cells. Mice without a microbiome had minimal nicotinic acid production, making cells in the upper colon more vulnerable to injury and disease.
The researchers also studied human colon tissue samples. They found that different parts of the human colon exhibit: Regional features similar to the pattern observed in mice. And this defense mechanism was reduced in samples from human patients with Crohn’s disease, a type of intestinal disease in which abnormal immune system activity causes inflammation.
Our study highlights the importance of studying host microbiome interactions with close attention to specific colon regions, rather than treating the colon as a homogeneous organ. We learned that the microbiome controls regional differences and tissue protection. ”
Dr. Jeremy Rispal, Postdoctoral Fellow, University of California, San Francisco, and lead author of this study
Further research will be needed to confirm the exact mechanism behind this protective effect and determine how these findings may be used for new treatments for intestinal diseases.
sauce:
Cedars-Sinai Medical Center
Reference magazines:
Rispal, J. Others. (2026). Nicotinic acid produced by the microbiome controls regional identity and susceptibility to injury in the colon. cell. DOI: 10.1016/j.cell.2026.02.007. https://www.cell.com/cell/abstract/S0092-8674(26)00172-8

