When elderly people stay active, their brains have more of a class of proteins that enhances the connections between neurons (神经元) to maintain healthy cognition (认知), a UC San Francisco study has found.
"Our work is the first that uses human data to show that synapse protein regulation (突触蛋白质调节) is related to physical activity and may drive the beneficial cognitive outcomes we see," said Kaitlin Casaletto, PhD, an assistant professor of neurology and lead author on the study. The beneficial effects of physical activity on cognition have been shown in mice but have been much harder to demonstrate in people.
The project tracked the late-life physical activity of elderly participants, who also agreed to donate their brains when they died. Maintaining the integrity of these connections between neurons may be vital to fighting against mental disorder, since the synapse is really the site where cognition happens. Physical activity — a readily available tool — may help boost this synaptic functioning.
Casaletto found that elderly people who remained active had higher levels of proteins that facilitate the exchange of information between neurons. This result agreed with the earlier finding that people who had more of these proteins in their brains when they died were better able to maintain their cognition late in life.
"It may be that physical activity generates a global sustaining effect, supporting the healthy function of proteins that facilitate synaptic transmission throughout the brain," Casaletto said.
The brains of most older adults store poisonous proteins that are the marks of mental illnesses, and the proteins can cause synapses and neurons to fall apart. "In older adults with higher levels of the proteins associated with synaptic integrity, this effect that leads to mental diseases appears to be weakened," she said. "The study shows the potential importance of maintaining synaptic health to support the brain against mental diseases like Alzheimer's."
