Exercise alters brain chemistry and prevents dementia - here’s how
5 December 2022
We’ve all heard that exercise is good for us, mainly how it strengthens our body and helps us prevent diseases. But many people don’t know about the other important benefits of exercise – that it can help in reducing ageing too.
It was already established that exercising lowers the risk of developing dementia. However, new research takes things one step further by starting to demonstrate exactly how this might happen. According to a study by University of California, exercise can help protect the brain against ageing, with this new data showing how physical activity can alter brain chemistry.
The University of California researchers showed that physical activity may help build synaptic health. Synapses are the connections which carry information between brain cells (neurones). They are critical for thinking, memory, decision making, perception and movement. Data from the researchers are the first to actually demonstrate a link between lifestyle behaviour, physical activity, and markers of synaptic integrity in human brain tissue. It was seen that when elderly people stay active, their brains have more of a class of proteins that enhances the connections between neurons to maintain healthy cognition.
The team found that elderly people who remained active had higher levels of proteins that facilitate the exchange of information between neurons. This result dovetailed with earlier findings that people who had more of these proteins in their brains when they died were better able to maintain their cognition late in life. To their surprise, the scholars found that the effects ranged beyond the hippocampus, considered the brain’s seat of memory, to encompass other brain regions associated with cognitive function. The research team believed that such an impact was found during brain autopsies of people with Alzheimer’s and other neurogenerative diseases. It could be possible that physical activity exerts a “global sustaining effect”, supporting and stimulating healthy function of proteins that facilitate synaptic transmission throughout the brain.
Synapses safeguard the brain from symptoms of dementia
The brains of older adults accumulate amyloid and tau – two proteins that are the hallmarks of Alzheimer’s disease pathology. Scientists believe that amyloid accumulates first, then tau, causing synapses and neurons to eventually fall apart.
The team at the University of California previously found that synaptic integrity, either measured in the spinal fluid of living adults or the brain tissue of autopsied adults, appeared to reduce the relationship between amyloid and tau, and between tau and neurodegeneration. They concluded that in older adults with higher levels of the proteins associated with synaptic integrity, the cascade of neurotoxicity that leads to Alzheimer’s disease appears to be attenuated. This potentially shows the importance of maintaining synaptic health to support the brain against Alzheimer’s disease.
The new data shows the benefits of physical activity and clearly sets out another reason to stay active in older age. As said, the brains of most older adults accumulate toxic proteins, which are the hallmarks of Alzheimer’s and related neurological diseases. Many researchers trust that toxins cause synapses and neurons to break down, and this study demonstrates the importance of maintaining synaptic integrity to slow down this process.
Living healthier and better
Because we are living longer, it is vital we understand better how we can age healthily. According to a US Census Bureau, the number of adults aged over 65 globally will double between 2025 and 2050, expecting to reach by 1.6 billion. This will only add more challenges as older adults are more affected by chronic ailments. It also means that cases of dementia are predicted to rise exponentially. This research has immense potential as it is helping us to understand the nature of the disease and allows us to develop new treatments and potential cures to improve the care for people.
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