Restoring Memory After Brain Damage Enabled by Neural Stem Cells

Research at the UC Irvine is among the first to demonstrate that neural stem cells may help to restore memory after brain damage.

In the study, mice with brain injuries experienced enhanced memory -- similar to the level found in healthy mice -- up to three months after receiving a stem cell treatment. Scientists believe the stem cells secreted proteins called neurotrophins that protected vulnerable cells from death and rescued memory. This creates hope that a drug to boost production of these proteins could be developed to restore the ability to remember in patients with neuronal loss.

“Our research provides clear evidence that stem cells can reverse memory loss,” said Frank LaFerla, professor of neurobiology and behavior at UCI. “This gives us hope that stem cells someday could help restore brain function in humans suffering from a wide range of diseases and injuries that impair memory formation.”

The results of the study appear Oct. 31 in the Journal of Neuroscience.

LaFerla, Mathew Blurton-Jones and Tritia Yamasaki performed their experiments using a new type of genetically engineered mouse that develops brain lesions in areas designated by the scientists. For this study, they destroyed cells in the hippocampus, an area of the brain vital to memory formation and where neurons often die.

To test memory, the researchers gave place and object recognition tests to healthy mice and mice with brain injuries. Memories of place depend upon the hippocampus, and memories of objects depend more upon the cortex. In the place test, healthy mice remembered their surroundings about 70 percent of the time, but mice with brain injuries remembered it just 40 percent of the time. In the object test, healthy mice remembered objects about 80 percent of the time, while injured mice remembered as poorly as about 65 percent of the time.