Exercise alters brain chemistry, protects aging synapses

This protective effect was found even in those whose brains were full of toxic proteins associated with Alzheimer's disease and other neurodegenerative diseases at autopsy

"Our work is the first to use human data to show that synaptic proteins are involved in regulating physical activity and may drive the beneficial cognitive outcomes we can see," said Kaitlin Casaletto, Ph.

The beneficial effects of physical activity on cognitive performance have been demonstrated in mice, but have been difficult to demonstrate in humans

Casaletto, a neuropsychologist and member of the Weill Institute for Neuroscience, collaborated with William Honer, MD, a professor of psychiatry at the University of British Columbia and senior author of the study, who utilized Data from the Memory and Aging Project at Rush University in Chicago

"Maintaining the integrity of the connections between neurons may be critical in preventing dementia because synapses are actually where cognition occurs," Casaletto said

More protein means better nerve signaling

Honer and Casaletto found that older adults who remained active had higher levels of proteins that help exchange information between neurons

To their surprise, the researchers found that the effects extended beyond the hippocampus, the brain's memory center, to include other brain regions associated with cognitive function, Honer said

"It may be that physical activity has a global lasting effect that supports and stimulates the healthy function of proteins that promote synaptic transmission in the brain," Honer said

Synapses protect brains showing signs of dementia

The brains of most older adults accumulate amyloid and tau, toxic proteins that are hallmarks of Alzheimer's disease

Casaletto previously found that synaptic integrity appears to be attenuated between amyloid and tau and between tau and neurodegeneration, both in the spinal fluid of living adults and in the brain tissue of autopsied adults.

"In older adults with higher levels of synaptic integrity-related proteins, this cascade of neurotoxicity leading to Alzheimer's disease appears to be attenuated," she said

Journal Reference :

1. Kaitlin Casaletto, Alfredo Ramos‐Miguel, Anna VandeBunte, Molly Memel, Aron Buchman, David Bennett, William Honer.