According to a recent report in the journal Cell Stem Cell, a shot of human stem cells may help rebuild the protective layer of neurons, damaged by radiation therapy – a popular cancer treatment.
The researchers directed human stem cells to become the types of neuroglia that become affected by the treatment, and grafted them onto the brains of lab rats blasted with radiation.
Two months later, the poor critters began to show clear improvements in memory and learning.
“This technique, translated to humans, could be a major step forward for the treatment of radiation-induced brain… injury,” said Jonathan Glass, a neurologist at Emory University in Atlanta.
Radiation therapy, while effective for some forms of cancer, often leaves patients with severe disability – even decreasing the adult IQs of young children who are forced to undergo the procedure.
“Fuzzy thinking, a loss in higher intellectual functions, decreases in memory – all those are part and parcel of radiation therapy to the brain,” noted Steve Goldman from the University of Rochester, New York.
Radiation has been found to destroy cells that mature into oligodendrocytes – a type of cell that provides support and insulation to axons in the central nervous system by covering them with what is known as the myelin sheath.
Without it, neurons lose their ability to transmit information, leading to memory loss and other neurological problems.
Rats who were given an injection into their forebrains showed better perception of objects in motion, while those who received a transplant into the cerebellum demonstrated improved balance.
Images of the rats’ brains revealed that most of the grafted cells survived and successfully restored the myelin sheath of the irradiated neurons.
“Being able to repair radiation damage could imply two important things: improving the quality of life of survivors and potentially expanding the therapeutic window of radiation,” said study co-author Dr. Viviane Tabar, MD. “This will have to be proven further, but if we can repair the brain effectively, we could be bolder with our radiation dosing, within limits.”
Tabar hopes to repeat the trial with a larger number of subjects and include other treatments (such as chemotherapy) that people often undergo while also receiving radiation therapy.