A new study from Cornell University has revealed that stem cells can delay their death to help heal the body. The research was focused on tiny worms called planarians because of their incredible ability to regenerate lost body parts with the help of stem cells.
“Planarian stem cells, even when challenged and under a lot of duress, will still respond to an injury by delaying death,” said study first author Divya Shiroor.
For the investigation, the researchers exposed planarians to radiation and then subjected half of them to injury. The group of worms with no injuries were found to experience predicted levels of stem cell death.
Among the injured worms, however, stem cells survived and gathered around the site of the wound. According to the researchers, these specialized cells actually postponed their death to mount a response to injury.
“We show that this inevitable radiation-induced cell death can be significantly delayed if animals are injured soon after radiation exposure,” said Shiroor.
The findings have major implications for cancer research and therapies, especially when it comes to chemotherapy and surgery options for patients.
“By understanding how injury prompts planarian stem cells to withstand radiation, we hope to identify genes that, if shared with mammals, could perhaps help hone existing therapies,” said Shiroor.
Planarians are a good proxy for studying the human body due to the similarities of their organs and genes.
On the other hand, planarians are much better at healing their wounds. This is because the worms have a larger volume of stem cells and a simple immune system that does not complicate the healing process like that of humans.
“This really simplifies the process of understanding the effects of both injury and radiation on stem cells, and allows us to study it directly without being hampered by parallel processes integral to wound healing, such as inflammation, that get simultaneously triggered in mammals,” said Shiroor.
The research may ultimately lead to the development of human stem cells that respond to injury in a much more efficient way.
The research team will continue to study planarians to investigate how the specialized cells are alerted to an injury and the role that other cells may play in the response.
“We have identified a key gene that is required for stem cell persistence after radiation and injury, and we plan on using this as a stepping stone for further exploration,” said Shiroor.
The study is published in the journal Current Biology.