Bacteria in the intestine protect against dangerous radiation exposure

A new study by scientists showed that certain bacteria in the intestines of laboratory mice were exposed to lethal levels of whole-body radiationprotect against radiation damage. Such radiation, absorbed in a clinical setting or during accidental exposure, can cause tissue damage. In this study, gut bacteria reduced radiation exposure and improved the recovery of blood cell production and gastrointestinal tract repair.

Protective shield of bacteria in the intestine during cancer therapy

The researchers found that one group of mice had high abundances of two types of bacteria in the gut. These were the so-called Lachnospiraceae and Enterococcaceae and were able to counteract the effects of intense radiation quite effectively. What is important for humans in this case is that these two types of bacteria are common in leukemia patients with mild symptoms who have undergone radiation therapy. The study showed that the presence of the two types of microbes led to increased production of small molecules. These are known as propionate and tryptophan. Such metabolites provided long-term protection from radiation and reduced damage to the production of stem cells in the bone marrow. They also mitigated the development of severe gastrointestinal problems and reduced DNA damage. Both metabolites can be purchased as dietary supplements in some countries. However, there is currently no evidence that such a dietary supplement could help people exposed to intense forms of radiation.

Damage to body organs from high levels of radiation, either through accidental exposure, cancer radiotherapy, targeted radiation attacks, and other forms of exposure, can result in serious illness and even death. Blood cells in the body and tissue in the tract renew themselves quickly and therefore remain particularly vulnerable to such damage from radiation therapy. However, on the protective side, the gastrointestinal tract is home to over 10 trillion microbial microorganisms. These could play an important role in limiting radiation-induced damage. The research yielded a comprehensive data set of bacteria and metabolites that can serve as a powerful resource for identifying actionable therapeutic targets in future microbiome studies.

Study results

Radiation therapy, which is often used to treat cancer, often causes side effects. The researchers therefore wanted to understand how their experiments on mice could be transferred to humans. They examined stool samples from 21 leukemia patients who were scheduled to receive radiation therapy as part of a grueling stem cell transplant. The scientists found that patients with shorter symptoms had significantly higher levels of Lachnospiraceae and Enterococcaceae than others. These results correlated closely with the results of research in mice. The authorsof the studyhowever, warn that much larger studies are needed to test these conclusions. The researchers hope to be able to start a clinical study on humans soon. This will allow them to test the benefits of administering these metabolites to patients receiving radiation.