Studying more than 400 human brains, scientists find new evidence that exercise benefits brain health

Source | The benefits of academic exercise with cloves are countless, not only can improve the body's metabolism, strengthen the body, but also bring pleasure and reduce stress
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At the same time, many studies have shown that exercise also has a positive impact on brain health
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Physical activity is associated with reduced incidence of Alzheimer's disease dementia
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It is estimated that physical inactivity can lead to 4 million cases of dementia
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However, the biological mechanisms underlying physical activity and human brain health are still being explored
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The accumulation of amyloid and tau proteins in the brain is considered a pathological feature of Alzheimer's disease
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Many scientists believe that the accumulation of these proteins eventually causes synapses and neurons to collapse
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In previous research, Kaitlin Casaletto's team at the University of California, San Francisco, found that synaptic integrity appears to be attenuated in amyloid and tau proteins, both in adult cerebrospinal fluid and in postmortem adult brain tissue.
and the relationship between tau protein and neurodegeneration
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On January 7, 2022, Kaitlin Casaletto's team published a research paper titled: Late-life physical activity relates to brain tissue synaptic integrity markers in older adults in the journal Alzheimer's & Dementia.
They found that when older adults remain active , their brains grew more of a class of proteins associated with synaptic integrity that strengthen the connections between neurons for healthy cognition
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The researchers analyzed data from 404 deceased individuals from the Rush Memory and Aging Project (MAP) at Rush University in Chicago
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The project tracked the physical activity of older participants, who also agreed to donate their brains after death
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After the participants died, the researchers performed autopsies on their brain tissue and analyzed multiple synaptic proteins (synaptophysin, synaptotagmin-1, vesicle-associated membrane protein [VAMP], synaptosome-associated protein 25 [SNAP-25], syntaxin, complexin-I, complexin-II), and modeled the relationship between the number and duration of physical activity in later life and the expression of synaptic proteins
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Physical activity in later life correlates with levels of synaptic proteins in the brain at death.
Participants wore activity monitors on their wrists for 10 days, and their rest/activity status was monitored and recorded 24 hours a day
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After statistical analysis, average later-life physical activity had little or no association with age at death, education, and gender
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More physical activity was associated with better motor performance in later life
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Analysis of synaptic protein levels in the participants' brain tissue revealed that more physical activity was associated with higher levels of synaptophysin, VAMP, SNAP-25, synaptotagmin-1 and syntaxin in the brain at death, but not with the protein complexins (complexin).
-I; complexin-II) no significant correlation
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Does the time lag between synapsin measurement and exercise affect the correlation between the two? Given that animal models suggest that the relationship between physical activity and synapsin outcomes shows both acute and long-term effects, the investigators divided the cohorts by time of death to better understand how the relationship between physical activity and synapsin outcomes in humans time dynamics
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The results of the analysis showed that the relationship between physical activity and synapsin levels increased in a dose-dependent manner the closer synapsin was measured to the time of death
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There were moderately sized positive associations between physical activity and all synaptic protein markers (except complexin-II) between 0 and 2 years after participant death
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This relationship weakened as the actigraphy measurement progressed further
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These data suggest that the proximity between physical activity and measurements of synaptic protein levels may be an important factor
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Are the correlations between physical activity and synaptic proteins the same in different regions of the brain? By analyzing the relationship between physical activity and synaptic protein levels in different regions of the brain, the researchers found that greater physical activity was more strongly associated with higher synaptic protein levels within 0 to 2 years of death, an effect that was observed in all cases.
are similar across brain regions
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Honer, one of the researchers, said they were surprised that the study found that physical activity affects synaptic proteins in the brain beyond the hippocampus, the brain's memory center, to include other brain regions associated with cognitive function.

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"It may be that physical activity exerts a systemic sustained effect that supports and stimulates the healthy function of these proteins, promoting synaptic transmission throughout the brain," Honer said
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The study showed that when older adults remained active, their brains became more of a type of protein associated with synaptic integrity that strengthens connections between neurons for healthy cognition
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The findings, taken together with the team's previous research, show the potential importance of maintaining synaptic health to support the brain's fight against Alzheimer's disease
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Dr.
Kaitlin Casaletto, lead author of the study, said: "Our work is the first to use human data to show that synaptic protein regulation correlates with physical activity and may drive beneficial cognitive outcomes
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Since synapses are where cognition occurs, maintaining The integrity of the connections between neurons may be critical in fighting off dementia
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Physical activity, which is simple and accessible, may help enhance this synaptic function
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In view of so many benefits of exercise, my friends are not quick to get active! Paper link: https://doi.
org/10.
1002/alz.
12530 Open for reprinting, welcome to forward to Moments and WeChat groups