MADISON (WKOW) -- The University of Wisconsin- Madison reports a study conducted there is the first to show that human stem cells can successfully implant themselves in the brain and then heal neurological deficits.
Once inside the mouse brain, the implanted stem cells formed two common, vital types of neurons, which communicate with the chemicals GABA or acetylcholine. "These two neuron types are involved in many kinds of human behavior, emotions, learning, memory, addiction and many other psychiatric issues," says senior author Su-Chun Zhang, a professor of neuroscience and neurology.
After the transplant, the mice scored significantly better on common tests of learning and memory in mice.
Zhang says location, timing and purity were critical for success. "Developing brain cells get their signals from the tissue that they reside in, and the location in the brain we chose directed these cells to form both GABA and cholinergic neurons."
The initial destruction was in an area called the medial septum. This area connects to the hippocampus, a vital memory center, by GABA and cholinergic neurons. Zhang says the connection is "fundamental to our ability to learn and remember."
Zhang says the process is similar to removing a section of telephone cable, finding the correct route, and wiring the replacement from either end.
"Cholinergic neurons are involved in Alzheimer's and Down syndrome, but GABA neurons are involved in many additional disorders, including schizophrenia, epilepsy, depression and addiction," says Zhang.
He notes that "for many psychiatric disorders, you don't know which part of the brain has gone wrong." Zhang suspects the new study will be used in creating models for drug screening and discovery.
The study by Zhang and first author Yan Liu, a postdoctoral associate, is published in the current issue of Nature Biotechnology.