Tiny 'water bears' may hold key to reducing radiation-induced side effects
Experts believe that a tiny near-microscopic animal may hold the key to reducing the severity of symptoms associated with radiation therapy.
Tardigrades are tiny aquatic animals typically less than a millimeter in size. When viewed under a microscope, they appear as plump, segmented creatures with flat heads and eight legs that have up to eight claws on the end. As if the physical description of these so called “water bears” or “moss piglets” weren’t eerie enough, the animals also have a party trick that makes them seem like something straight from a sci-fi movie—they're virtually indestructible.
These animals have long outlived the dinosaurs due to their ability to withstand extreme cold, heat and other natural disasters. They also are known to tolerate huge amounts of radiation—up to 2,000 times the amount humans can. This fact recently caught the attention of researchers from MIT, Brigham and Women’s Hospital and the University of Iowa.
Inspired by the survival mentality of the tiny water bears, the team sought to determine if some aspect of tardigrade's chemical makeup offered it an advantage over all the species it has outlived thus far. The group focused on a protein tardigrades are known to carry called Dsup. This is the key to the creature’s natural defenses against radiation-induced injury.
“Radiation can be very helpful for many tumors, but we also recognize that the side effects can be limiting. There’s an unmet need with respect to helping patients mitigate the risk of damaging adjacent tissue,” noted Giovanni Traverso, MD, PhD, an associate professor of mechanical engineering at MIT and Brigham and Women’s Hospital gastroenterologist.
Researchers hypothesized that by delivering messenger RNA encoding Dsup to patients scheduled to undergo radiation therapy, it could help mitigate some of the treatment’s most unpleasant side effects. They predicted that injecting the mRNA into tissue would prompt patients’ cells to express the protein, thus protecting their own DNA.
After settling on a suitable delivery method that included two polymer-liquid particles, the group put their theory to the test in mice. They injected a group of mice in the cheek or rectum with the mRNA-carrying particles hours before exposing them to a dose of radiation. In doing this, they observed a 50% reduction in the amount of double-stranded DNA breaks induced by radiation damage.
What’s more, the mRNA did not migrate beyond the injection site. This is important because its purpose is to protect the tissue near the tumor from radiation damage, not the tumor itself.
The next phase of research will focus on developing an appropriate remedy for humans. The group has plans to concoct a version of the protein that will not invoke an immune response, as it’s likely that it would if deployed in humans in its current form. If successful, the team believes their method can be utilized in both radiation and chemotherapy to improve patients’ treatment experience.
Learn more about their work here.
In addition to her background in journalism, Hannah also has patient-facing experience in clinical settings, having spent more than 12 years working as a registered rad tech. She began covering the medical imaging industry for Innovate Healthcare in 2021.