Rejuvenating the brain
Unfortunately, the older a person gets, the more difficult it is for him to remember or learn something new. The reasons behind these changes are still unclear, but the staff of the Center for Regenerative Therapy at the Technical University in Dresden undertook to find out whether increasing the number of stem cells in the brain will help restore cognitive functions such as learning and memory, which are lost with aging.
The research team led by Professor Federico Calegari used their own method to stimulate a small pool of neural stem cells that are located in the brain in order to increase their number and, as a result, increase the number of neurons generated by these stem cells. Surprisingly, the additional neurons were able to survive in the brains of old mice and form new contacts with neighboring cells.
The scientists also investigated a key cognitive function that is lost in mice and humans during aging: spatial orientation.
It is well known that people learn to navigate in a new environment in different ways, depending on age. In youth, the brain can build and memorize a cognitive map of the environment, but this ability disappears in the aging brain. As an alternative solution to the problem, the brain of an elderly person without a cognitive map of the environment must memorize a fixed series of turns that are necessary to reach a certain destination. These two strategies may seem similar at first glance, but only a cognitive map helps people navigate effectively when starting from a new place or when they need to reach a new destination.
Will the increase in the number of neurons be sufficient to counteract the decrease in the brain's performance in orientation and slow down this aging process? Yes. Old mice with a large number of neuron stem cells regained their lost ability to map the environment and memorized it better, becoming more like young mice. When neural stem cells were stimulated in the brains of young mice, cognitive impairment was delayed and memory was better preserved throughout the animal's natural life.
Neural stem cells and new neurons (green) artificially created in the hippocampus of the mouse brain and in contact with mature cells (red). Source: TU Dresden.
In young people, the hippocampus is crucial for remembering places and events, it is responsible for creating new maps of the area. But older people use other brain structures for navigation, which are more related to the development of habits. Surprisingly, the increase in the number of neurons in the hippocampus of old mice allowed them to use strategies typical of young animals. Not only did they learn quickly, the learning process itself changed.
People have a small number of stem cells in the brain, and it decreases significantly during life. This is one of the underlying causes of cognitive deficits in aging, and the preservation of stem cells is essential for a rapidly aging society. This work demonstrates that age-related changes can be slowed down by preserving the neurogenic potential of the brain and thus rejuvenating its functions.
Article by G.Berdugo-Vega et al. Increasing neurogenesis refines hippocampal activity rejuvenating navigational learning strategies and contextual memory throughout life is published in the journal NatureCommunications.
Aminatadzhieva, portal "Eternal youth" http://vechnayamolodost.ru based on TU Dresden: Rejuvenatingthebrain: Rejuvenating the brain: more stem cells improve learning and memory of old mice.