Radiotherapy is an anti-cancer treatment that can have side effects,media New Atlas reported. Gastrointestinal discomfort is a common side effect, but researchers have only now discovered how the large bacterial populations that live in the gut are affected by acute radiation. A new study led by scientists at the University of North Carolina at Chapel Hill suggests that certain bacterial species may actually provide protection from the harmful effects of radiation.
Recent research provides incredible new insights into the relationship between cancer and the gut microbiome. In addition to potentially affecting cancer risk and accelerating metastasis, specific types of gut bacteria have been found to help or hinder responses to treatment.
A new study published in the journal Science presents new evidence that certain types of gut bacteria can protect organisms from radiation-induced damage. The study first identified a small group of mice with a peculiar ability to survive high doses of radiation that kills most other mice.
The researchers referred to the mice as “elite survivors” and examined their gut microbiomes to find out how certain bacterial species gave this unexpected radiation protection. These “elite survivors” were found to contain two highly rich bacteria: Lachnospiraceae and Enterococcaceae.
Further investigations revealed that two metabolites produced by bacteria, alanine and tryptophan, appeared to play a role in protecting animals from the adverse effects of radiation exposure. These metabolites help reduce radiation-induced DNA damage and damage to bone marrow stem cell production.
To validate these findings in humans, the researchers analyzed a group of leukemia patients who received active radiotherapy. They found that those with the least adverse radiation side effects had the highest number of Lachnospiraceae and Enterococcaceae in their bodies.
Subsequent animal tests showed that direct treatment with alanate and tryptophan made mice resistant to radiation damage. A closer analysis found that “an area of metabolites affected by radiation has increased selectively among elite survivors”.
Jenny P.Y. Ting, the new study’s co-author, is cautious about not clearing the line from animal research to humans. She recommends that larger studies be needed to validate findings in the human world before doctors and patients start taking probiotics or post-probiotics in conjunction with radiotherapy.
“The granulocyte cluster stimulation factor is the only drug approved by the FDA as an effective response to high doses of radiation exposure, but it is expensive and has potentially adverse side effects,” Ting said. “However, the bacteria we can culture, especially relatively inexpensive metabolites, are already elements of the food we eat and may be a good choice.”
Currently, a clinical trial is being planned to explore whether direct giving of these metabolites to patients receiving radiation therapy can reduce adverse reactions.
The new study was published in the journal Science.