Scientists at the Dresden Center for Regenerative Therapies (CRTD) in Germany have shown that the growth of stem cells in the brains of old mice helps improve cognitive functions such as memory and learning that are lost with age, in a published study. In the journal ‘Nature Communications.’
As we age, the brain finds it more difficult to learn and remember. Professor Federico Calegari’s team has verified in his laboratory that adding more neurons to the hippocampus of these mice, a crucial area for remembering places and events, is enough to improve their sense of navigation and also slow down the aging process of their brain. The researchers have realized that these additional neurons can survive and form new contacts with their neighboring cells in the brains of old mice, which had lost their cognitive ability to navigate.
Individuals learn to move in new environments differently, depending on whether they are old or young. When they are young, the brain can build and remember a cognitive map of the environment, but that ability disappears as the brain ages. So the older brains have to learn a series of paths and turns necessary to reach their destination.
Although these two strategies would seem similar, in reality, the construction of a map allows the individual to navigate more efficiently from a new location or when he has to find new ways to reach a new destination. Older individuals tend to rely more on habits than on creating new maps of their environment.
Would this increase in neurons be enough to counteract this deficiency of the brain in navigation and slow down its aging process? The work of Professor Calegari’s team, together with Professor Gerd Kempermann from the German Center for Neurodegenerative Diseases and Dr. Kentaroh Takagaki, from the University of Magdeburg, have answered in the affirmative.
Old mice that had lost their ability to map their environment and remember them for a long time were able to regain this ability of younger mice and greatly speed up their learning. In addition, it not only highlighted how quickly they learned, but “how different was the learning process itself,” says Gabriel Berdugo-Vega, the first author of this study.
“Humans also have some stem cells in the brain that are known to decrease severely in number throughout their lives. Identifying the underlying causes of cognitive deficits in aging is crucial in a society like ours that ages so fast, “says Professor Calegari, senior author of the study. “Our work demonstrates that these age-related deficiencies can be rescued using the brain’s neurological potential to rejuvenate its functions,” he continues.
With this research, the team of Professor Federico Calegari aims to discover the principles of cell regeneration and use their expert knowledge on stem cells to apply them in the treatment and investment of certain neurodegenerative diseases such as Alzheimer’s or Parkinson’s, hematological diseases such as leukemia, metabolic diseases like diabetes and bone or retinal diseases.