It was once believed that mammals were not able to create new neurons throughout their life. However, over the past few years, scientists have found that at least two brain regions – the hippocampus and the centers of the sense of smell – grow neurons throughout their lifetime.
Researches have shown, in mice, that one type of stem cell that makes adult neurons in the brain hippocampus throughout life. These findings are valuable as they may help neuroscientists figure out how to maintain youthful conditions for memory and learning, regenerate and repair parts of the brain after aging and injury.
The researchers showed that the neural stem cells they found had a common molecular signature across the mice lifespan. They accomplished this bylabeling the neural stem cells in embryos when the brain was still developing and following the cells from birth into adulthood.
This method revealed that new neural stem cells with their forerunner’s label were endlessly making neurons throughout an animal’s lifetime.
Guo-li Ming, MD, PhD, a professor of Neuroscience stated that this process is unique in the brain. The cells in the hippocampus never stop replicating and contribute to the flexibility of the brain.
This capacity is called plasticity, which is the brain’s capability to form new connections throughout life to compensate for diseases, injuries and to adjust to any new inputs from the environment.
The research team’s next step is to look at the same stem cells in other mammals, most importantly in humans.