Researchers Discover a Way to Restore Memories

Researchers at the University of California Irvine were able to demonstrate that neural stem cells may be able to restore memories after brain damage.

According to Frank LaFerla, a professor of neurobiology and behavior at the University of California, Irvine, their research proves that stem cells can reverse memory loss and thus give hope that stem cells could someday restore brain function in persons suffering from diseases and injuries that damage memories.

LaFerla together with Mathew Blurton-Jones and Tritia Yamasaki conducted their experiment on mice by giving them brain lesions in the hippocampus, the area of the brain associated with memory formation. They did gave an object and place recognition test on both healthy mice and mice with brain lesions. The results showed that in the place test, the healthy mice were able to remember their surroundings about 70 percent of the time while mice with brain injuries were only able to remember their surroundings 40 percent of the time.

The scientists then injected the mice with brain injuries with genetically engineered neural stem cells which they colored green so that they can track it inside the mouse's brain after transplantation. About 200,000 neural stems cells were transplanted into each mouse. Three months after injecting the stem cells, the scientists did a place test on the mice and found that the mice injected with neural stem cells were able to remember their surroundings 70 percent of the time, the same percentage as that of the healthy mice, while the other mice that had brain injuries but did not receive neural stem cells injection still had trouble remembering their surroundings.

The scientists then studied the behavior of the neural stem cells in the brain and found that only four percent of the transplanted stem cells turned into neurons. These lead scientists to believe that the transplanted stem cells were not improving memory by replacing the dead brain cells but they believe that the stem cells are actually enhancing the brain environment by making beneficial proteins. These beneficial proteins are called neurotrophins and according to the scientists, they protect vulnerable cells from death, thus saving memories.

Scientists believes that if the neurotrophins are responsible for saving memories, they could try and make a drug that could produce or foster the production of the proteins. According to the researchers, with this discovery, scientists can now spend less time turning stem cells into neurons when it comes to memory research since they didn't actually made neurons to improve the memory.

The results of the UCI study appeared in the October 31 issue of the Journal of NeuroScience.

SOURCE:

University of California, Irvine. "Stem cells can improve memory after brain injury". UCI.edu