A new study developed by the University of California San Francisco (United States) and published in the journal 'Alzheimer's & Dementia: The Journal of the Alzheimer's Association' assures that physical exercise also helps combat aging of the brain.
This is so because when older people are physically active, their brains have more of one type of protein than improves neural connections, helping to maintain healthy cognition.
The study that concerns us found this protective effect even in people whose brains at autopsy were plagued with toxic proteins associated with Alzheimer's or other types of neurodegenerative pathologies.
In this regard, Professor Kaitlin Casaletto explains that “our work is the first to use human data to show that the regulation of synaptic proteins is related to physical activity and can drive the beneficial cognitive results that we observe.”
Demonstrated brain benefits in humans
Until now, the benefits of physical activity for the brain and cognition had been demonstrated in mice. However, it has been much more complicated to certify in humans.
Casaletto, a neuropsychologist and member of the Weill Institute of Neurosciences, argues that “maintaining the integrity of these connections between neurons can be vital to avoid dementia, since the synapse is really the place where cognition occurs. Physical activity – a readily available tool – can help boost this synaptic function.”
This project tracked elderly participants and their physical activity. Furthermore, these participants agreed to donate their brains to science when they died.
Thus, this group of researchers was able to observe that older people who were physically active offered higher levels of proteins that favor the exchange of information between neurons.
For his part, William Honer, professor of psychiatry at the University of British Columbia and lead author of the study, who worked hand in hand with Casaletto, confesses that “it may be that physical activity exerts a global maintenance effect, supporting and stimulating the healthy function of proteins that facilitate synaptic transmission throughout the brain.”
Physical exercise against dementia
On the other hand, most brains of older people tend to accumulate amyloid and tau, two toxic proteins typical of Alzheimer's disease. In relation to this, a large number of scientists think that amyloid accumulates first and then tau, generating the collapse of synapses and neurons.
Previously, researcher Casaletto found that synaptic integrity, whether measured in the cerebrospinal fluid of living adults, or in the brain tissue of dead adults, seemed to dampen the relationship between amyloid and tau; and enters the tau and neurodegeneration.
In conclusion, the neuropsychologist Casaletto states that “in older adults with higher levels of proteins associated with synaptic integrity, this cascade of neurotoxicity that leads to Alzheimer's disease seems to be attenuated. Taken together, these two studies show the potential importance of maintaining synaptic health in supporting the brain against Alzheimer's disease.”