New study reveals why exercise is vital for Parkinson’s brain health
Physical activity raises dopamine, a key target in fighting the disease
- Aerobic exercise significantly increases dopamine release in the brain.
- This helps improve movement and coordination, offsetting dopamine loss in aging and Parkinson's.
- Regular physical activity is vital for brain health and motor performance.
Aerobic exercise triggers a surge of dopamine in the brain that can significantly improve movement and coordination during the aging process, a new study in mice suggests.
By providing “neurochemical evidence” for the benefits of staying active, researchers found that regular physical activity can help offset the natural decline of this key chemical messenger, a discovery with significant implications for individuals living with Parkinson’s disease.
The loss of dopamine, which helps control everything from motivation to motor function, is a hallmark of both Parkinson’s and healthy aging.
“These results provide neurochemical evidence for why exercise improves everything from memory to movement to mood, all of which are affected in people with Parkinson’s disease,” Margaret E. Rice, PhD, a professor at the New York University (NYU) Grossman School of Medicine, and the study’s lead author, said in an NYU Langone Health news story.
The study, “Voluntary exercise increases striatal dopamine release and improves motor performance in aging mice,” was published in the journal npj Parkinson’s Disease.
Why dopamine matters for aging and Parkinson’s
As people age, many experience gradual declines in mobility and cognitive function. One contributor to these changes is a reduction in dopamine, a neurotransmitter that plays a crucial role in movement, motivation, and learning.
Dopamine-producing nerve cells supply the striatum, a brain region critical for motor control. Degeneration of these cells in Parkinson’s disease leads to a profound loss of dopamine, resulting in hallmark motor symptoms such as slowed movement and impaired coordination. Even with healthy aging, dopamine signaling can weaken, resulting in milder but similar movement difficulties.
Exercise is widely recognized as one of the most effective ways to support brain health with age. Aerobic activity has been shown to promote nerve cell growth, strengthen communication between brain cells, and increase levels of protective molecules involved in memory and learning. In people and animal models, regular physical activity improves motor and cognitive function, including in models of Parkinson’s disease.
Previous work from researchers at NYU Langone Health showed that voluntary exercise in young male mice, roughly equivalent to humans in their late teens and early 20s, increased dopamine release in key motor regions of the brain. This effect was thought to help explain the movement-related benefits of exercise.
In the new study, researchers asked whether similar benefits could be seen in older animals. They studied 12-month-old mice, roughly comparable to humans in their 50s, and allowed them unlimited access to a freely rotating wheel for 30 days. Mice housed with locked wheels, and therefore unable to exercise, served as the control group.
During and after the mice’s exercise period, the researchers measured dopamine release in several striatal brain regions and evaluated motor behavior, including movement speed, coordination, and overall activity levels. They also examined whether acetylcholine, which is another brain chemical known to influence dopamine signaling, contributed to exercise-related effects.
Strong capacity for recovery in the aging brain
The results showed that voluntary exercise significantly increased dopamine release across multiple striatal regions in both aging male and female mice compared with controls. Notably, the magnitude of these increases was similar to those previously observed in much younger animals, suggesting the aging brain retains a strong capacity to respond to physical activity.
“Our findings make clear that the impact of exercise on brain health and mobility is not exclusive to the young,” Rice said. “By getting enough physical activity, we can still heighten dopamine release to help us move faster and more easily.”
Although female mice ran about twice as much as the males, both groups showed similar increases in dopamine and movement. This suggests that a moderate amount of exercise is enough to raise dopamine levels, and doing more does not provide additional benefits, according to the researchers.
Exercise was also linked to improvements in function. Mice that ran on the wheel moved faster in open-field tests and performed better on tasks requiring motor coordination, such as descending a vertical pole. However, exercise did not significantly affect fine motor skills or grip strength, indicating that its benefits were specific to certain aspects of movement.
Further experiments showed the dopamine-boosting effects of exercise were largely independent of acetylcholine signaling, indicating a direct impact of physical activity on dopamine-releasing nerve cells.
Overall, the findings suggest regular voluntary exercise can enhance dopamine signaling and improve motor performance, even in later life. Physical activity may help offset age-related declines in mobility and could be relevant for understanding how exercise supports movement and brain health in aging populations, the researchers noted.
The team now plans to use mouse models of Parkinson’s to expand on these results.
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