How exercise helps keep your memory sharp

One fun study Recently made shows how a file physical exercise strengthens health brain. Research, conducted on rodents, found that a hormone secreted by muscles during exercise enters the brain and strengthens the health and functioning of neurons, improves mental and practical operation. memory In the case of healthy animals and those with copy Alzheimer’s disease in rodents. A previous study showed that people produce the same hormone during exercise, and the results of the two studies together suggest that movement alters the pathway memory loss employment Elderly it’s at mad.

We have plenty of evidence that Playing sports It’s good for brain. Studies in people and animals have shown that exercise leads to Creating new neurons It is in the brain’s memory center and helps those new cells survive, mature, and integrate into the brain’s neural network, where they improve thinking and remembering functions. Extensive epidemiological studies also indicate that active people They have less tendency To develop Alzheimer’s disease And other types of dementia who rarely exercise.

But how does exercise affect the internal activity of our brain at the molecular level? Scientists hypothesize that Playing sports It can directly change the biochemical environment within the brain without muscle interference. Instead, muscles and other tissues release substances during physical activity that go to the brain and trigger processes there, leading to a subsequent improvement in mental health. But in this case, the substances would have to pass through the protective and particularly impermeable blood-brain barrier that separates our brain from the rest of our bodies.

These woven fabrics were of particular interest a decade ago to a large group of scientists at Harvard Medical School and other institutions. In 2012, Stanley J. Korsmeyer Professor of Cell Biology and Medicine at the Dana-Farber Cancer Institute and Harvard Medical School Identified a previously unknown hormone Produced in the laboratory in the muscles of rodents and humans during exercises, which are released into the bloodstream. They named the new hormone Irisina, based on the name of the goddess of the apostle Eris from Greek mythology.

By observing the pathway of irisin in the blood, they found that it often shelters in adipose tissue, where it is absorbed by fat cells, triggering a series of biochemical reactions that contribute to the browning of normal white fat. This brown fat is more metabolically active than the more common white type. It burns a lot of calories. So IrisinaBy helping to produce brown fat, it also helps increase our metabolism.

But Spiegelman and colleagues suspected that irisin also played a role in Brain health. Study conducted in 2019 Other researchers showed that it was produced in the brains of mice after exercise. Previous research also revealed the hormone in most human brains in the Brain Bank — unless the donors had died from Alzheimer’s disease In this case, your brain does not have this hormone.

The study suggested that aricin reduces the risk of dementia. And in the new work published this week in the magazine nature metabolism, Spiegelmann and his collaborators, including Christian D. Ran, MD, a professor at Massachusetts General Hospital and Harvard Medical School and author of the new study.

They began by breeding mice that were congenitally incapable of producing aricin, and then subjected them and other normal adult rats to exercise Playing sports On wheels for a few days is something the animals seem to enjoy. This type of exercise usually improves performance in tests on mice. memory NS The period of training in the profession. But animals unable to produce irisin showed a slight improvement in cognition, leading the researchers to conclude that the hormone is important in the case of exercise to strengthen mental activity.

Then take a closer look at the brains of the mice that practiced it exercises With or without the ability to produce irisin. They all contain more newborn neurons than the brains of stable mice. But in animals without the hormone, the new cells looked strange. There were a few synapses, junctions where brain cells send and receive signals, and dendrites that allow neurons to connect to the neural communication system. The researchers concluded that these newly formed neurons easily integrate into the existing brain network.

But when scientists used chemicals to increase licorice levels in the blood of animals unable to produce it, the situation changed markedly. The youngest mice, the oldest, and even those with advanced cases Alzheimer’s disease He started doing better on tests of memory and ability to learn. The researchers also found signs of reduced inflammation in the brains of animals with dementia, which is significant since then Inflammation of neurons is thought to accelerate memory loss.

Taken together, these new experiences strongly suggest that irisin is a key component in “associating exercise with cognition,” Spiegelman said.

It may one day be developed as a drug. Spiegelman and his collaborators hope to one day test whether pharmaceutical versions of iris slow cognitive decline or increase thinking ability in people with iris disease. Alzheimer’s disease.

This was a study in mice and a lot of research will be needed to determine if our brains react like rodents to irisin. It is also not known when or what types of files Playing sports They further amplify our hormone levels. So far, the study reinforces the idea that exercise may be “one of the most important regulators” of brain health, Christina Wran said. / Translation by TEREZINHA MARTINO

The New York Times Licensing Group – All rights reserved. Reproduction of any kind without written permission of the New York Times is prohibited.