Exercise keeps neurons alive!

After I started studying neurology, one of the most asked questions was: How to prevent Alzheimer's? As the world's largest neurodegenerative disease, the shadow of Alzheimer's disease looms over 9.
83 million elderly people in my country[1], making people at any age unable to help worry: Will I get Alzheimer's? ? What can I do now to prevent it? Some scientists say: exercise is enough
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Clinical studies have confirmed that exercise has a protective effect on the brain and promotes the growth of cerebral gray matter, but the mechanism of exercise protecting the brain is still unknown
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Some animal studies have found that exercise can promote synaptic growth and enhance synaptic function [2], but animals are not humans after all, and it is still far from clinical research on animals
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Fortunately, the maintenance effect of exercise on synapses has really found evidence in humans
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Scientists from the United States, Canada and Spain jointly published an article using 404 brain specimens donated after death and found that in old age, people with more daily exercise had higher expression of synaptic marker proteins in the brain, indicating that their Synaptic integrity is better preserved
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The study was published in Alzheimer's & Dementia, the top journal of Alzheimer's disease [3]
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This is also the first time that a human study has demonstrated the effect of exercise on synaptic function
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To complete the study, the researchers spent years recording the subjects' daily movements for 10 days each year until their death
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In order to comprehensively and objectively record the daily movement of the subjects, the researchers fixed the movement monitoring device on the wrist of the non-dominant hand of the subjects.
The monitoring device would send a movement record every 15 seconds for 10 days
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During this time, every action will be recorded natively
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The subjects included in the study were older people who, after their death, donated their brain tissue to researchers for the detection of synapse-related proteins in the brain tissue
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The researchers extracted gray matter from six different brain regions of each donor's brain and measured levels of seven synaptic proteins
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After collecting the above data, the researchers found that daily exercise was positively correlated with the expression of synaptic proteins, and answered three questions for us
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First, is the difference in synaptic protein expression caused by exercise? People's daily movements are very complicated.
They dance when they are happy, and do a lot of body movements when they are happy chatting.
Many hand movements do not represent sports
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At the same time, the condition of synapses is also affected by physical conditions, and synaptic damage is one of the pathological manifestations of many diseases
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Taking the two scenarios into consideration, the researchers based their data on three confounders of daily movement: social status, cognitive activity (activities related to reading and writing) and depression, as well as the presence of nine neurological disorders.
The disease situation has been adjusted, and the results still show that the more daily exercise, the stronger the exercise ability and the higher the synaptic protein expression
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The correlation between the 7 synaptic proteins and the level of exercise is shown in the figure.
Second, since each subject participated in the study and the time to death from exercise monitoring was different, whether or not the time of exercise has an impact on the test results.
of? It does
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When the subjects were grouped according to the time of death from the exercise monitoring results, the difference in synaptic protein expression was more obvious in the data monitored one year before death, and when the difference between the exercise monitoring and death was more than 3 years, the difference was more obvious.
No longer significant, nor did the nine neurological disease states affect their relationship
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This difference was most pronounced in patients with MCI (mild cognitive impairment, considered an intermediate stage between health and dementia)
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The correlation between 7 synaptic proteins and exercise levels is shown in the figure, where orange is the exercise level 0-2 years before death, and green is the exercise level 3-10 years before death.
Finally, since it is the expression difference caused by exercise, then Will it only appear in the motor cortex and have no effect on those brain areas that are not related to movement? Not so
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As mentioned earlier, this study selected 6 brain regions of each subject and found that there were motor-related correlations in the hippocampus, middle frontal lobe, inferior temporal gyrus, calcarine cortex, ventromedial caudate nucleus, and putamen.
differences in synaptic protein expression
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The boring knowledge is over, and it's time for us to summarize
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The most important message from this article is, of course, that exercise exerts neuroprotective effects by enhancing synaptic function
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Second, the benefits of exercise to the brain are time-sensitive
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So don't take chances, this year's exercise may not necessarily protect your brain next year, and exercise has to persist for a long time
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Of course, this also gives some inspiration to clinical exercise therapy.
The prodromal state of diseases such as MCI may be an important intervention window, and a reasonable exercise program can be designed to delay its progression
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Finally, exercise not only has a synaptic regulation effect on the motor-related cortex, but also positively promotes the synaptic function of the whole brain cortex
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This also explains why more exercise can not only improve athletic ability, but also improve cognitive level and memory ability, etc.
, making people more "smarter" [4,5]
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Although this study has only done a little exploration on the mechanism of exercise to protect the brain, it also illuminates the direction for the application of exercise therapy in a variety of neurological diseases
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However, this study only shows that exercise can increase the expression of synaptic function-related proteins, suggesting an enhancement of synaptic function
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However, the regulation of synaptic function by exercise may be complex and bidirectional.
This study only selected the node of death to explore, which can only reflect a long-term overall situation
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Second, the study did not document which type of exercise was most helpful in enhancing synaptic function
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The several synaptic proteins selected in the final article are just a few representatives of synaptic proteins.
If we want to find out what kind of upstream and downstream pathways these up-regulated synaptic proteins play, there is still a lot of research to be done.
Let's continue to look forward to it
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Everyone reading this article, don’t use the excuse that you are busy with work and have no time to exercise.
The increase in daily exercise is also good for the brain, even if it is to stand up from the computer and go to the toilet.
In short, being more active is good.
of
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At the end of the article, I would like to express my high respect to the 404 elderly people who participated in the research and donated their brain tissue after death, and to everyone who is willing to donate their bodies to scientific research
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Your bravery and dedication are invaluable to the development of science and the advancement of medicine
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 Reference: [1] Jia L, Du Y, Chu L, et al.
Prevalence, risk factors, and management of dementia and mild cognitive impairment in adults aged 60 years or older in China: a cross-sectional study.
Lancet Public Health .
2020;5(12):e661-e671.
doi:10.
1016/S2468-2667(20)30185-7[2] Horowitz AM, Fan X, Bieri G, et al.
Blood factors transfer beneficial effects of exercise on neurogenesis and cognition to the aged brain.
Science.
2020;369(6500):167-173.
doi:10.
1126/science.
aaw2622[3] Casaletto K, Ramos-Miguel A, VandeBunte A, et al.
Late-life physical activity relates to brain tissue synaptic integrity markers in older adults [published online ahead of print, 2022 Jan 7].
Alzheimers Dement.
2022;10.
1002/alz.
12530.
doi:10.
1002/alz.
12530[4] De Miguel Z, Khoury N, Betley MJ , et al.
Exercise plasma boosts memory and dampens brain inflammation via clusterin.
Nature.
2021;600(7889):494-499.
doi:10.
1038/s41586-021-04183-x[5] Albergaria C, Silva NT, Pritchett DL, Carey MR.
Locomotor activity modulates associative learning in mouse cerebellum.
Nat Neurosci.
2018 ;21(5):725-735.
doi:10.
1038/s41593-018-0129-x Editor in charge｜Ying Yuyan