Credit: Kira Mosher, University of California, Berkeley
After a challenging day at work or school, sometimes it may seem like you are down to your last brain cell. But have no fear—in actuality, the brains of humans and other mammals have the potential to produce new neurons throughout life. This remarkable ability is due to a specific type of cell—adult neural stem cells—so beautifully highlighted in this award-winning micrograph.
Here you see the nuclei (purple) and arm-like extensions (green) of neural stem cells, along with nuclei of other cells (blue), in brain tissue from a mature mouse. The sample was taken from the subgranular zone of the hippocampus, a region of the brain associated with learning and memory. This zone is also one of the few areas in the adult brain where stem cells are known to reside.
Infusing blood from younger creatures into older ones in hopes of halting—or even reversing—the aging process may sound like a macabre scene straight out of “Game of Thrones.” However, several scientific studies have shown that when older animals receive blood from younger counterparts, it improves the function of stem cells throughout the body, boosting tissue regeneration and healing. What’s not been clear is whether this activity can also rejuvenate the brain’s cognitive powers.
Let’s face it: aging is tough on the brain. The number of neural stem cells shrinks, producing fewer neurons; and many of the genes that promote brain development and neural connections become less active. To find out if young blood might hold some of the answers to this complex problem, two teams of NIH-funded researchers—one in Massachusetts and the other in California—recently turned to mice as a model system.