A single population of neural stem cells contributes to the continuous production of neurons in the adult hippocampus.
Though it was once believed that no neurogenesis occurred in the central nervous system post birth, in the past few years neuroscientists have demonstrated the regenerative ability of the olfactory system and the hippocampus.
In a study recently published in Cell, researchers from the University of Pennsylvania (PA, USA) have found the source of such a capability and demonstrated that, in murine models, a single population of neural stem cells are responsible for the development of new neurons in the hippocampus. The cellular activity in this brain region, known for its role in learning and memory, may provide inspiration for neuroscientists in their attempt to figure out ways to repair and regenerate parts of the brain after injury and aging.
"In the hippocampus, these cells never stop replicating and contribute to the flexibility of the brain in mammals."
“We’ve shown for the first time, in mammals, that neurons in the dentate gyrus of the hippocampus grow and develop from a single population of stem cells, over an entire lifespan,” explained co-senior author Hongjun Song. “The new immature neurons are more flexible in making connections in the hippocampus compared to mature neurons, which is paramount for healthy learning, memory, and adjusting mood.”
By labeling neural stem cells in a still developing embryo, the researchers were able to show that the cells had a common molecular signature across the lifespan of the mice. New stem cells with their precursor’s label were found to be continuously making new neurons throughout the lifetime of the animal.
“This process is unique in the brain,” commented co-senior author Guo-li Ming. “In the hippocampus, these cells never stop replicating and contribute to the flexibility of the brain in mammals.”
The plasticity of the brain and its ability to compensate for injury and form new connections is relatively well understood, though the results of this study are some of the first to demonstrate its regenerative capacity.
The next steps for the team will be to look at this stem cell population in greater detail in other mammals, including humans, and investigate how the cells are regulated.
Written By Jenny Straiton
Updated 13 May, 2019
Source Berg DA, Su Y, Jimenez-Cyrus D. A common embryonic origin of stem cells drives developmental and adult neurogenesis. Cell. 177(3), 654-668 (2019); https://www.cell.com/cell/fulltext/S0092-8674(19)30159-X?_returnURL=https%3A%2F%2Flinkinghub.elsevier.com%2Fretrieve%2Fpii%2FS009286741930159X%3Fshowall%3Dtrue https://penntoday.upenn.edu/index.php/news/researchers-discover-source-new-neurons-brain-hippocampus