The mechanics of why exercise is good for brain health, memory
07/13/2019 // Edsel Cook // Views

An international study presented further evidence that irisin protects neurons in the brain from degeneration. It showed that the so-called "exercise-induced hormone" can improve memory in humans and mice.

First identified in 2012 by researchers from the Harvard Medical School, irisin is a messenger hormone that helps convert white fat into brown fat, which produces heat. It was named after Iris, the heavenly messenger of the gods in Greek mythology.

Irisin levels increase whenever the body performs intense physical activities. Its discoverers believe that the hormone plays a significant role in the numerous health benefits enjoyed by the body during sessions of aerobic exercise.

"Exercise can improve cognitive function and has been linked to the increased expression of brain-derived neurotrophic factor (BDNF)," explained Harvard researcher Christiane Wrann. (Related: Physical exercise reduces severity of Alzheimer’s symptoms.)

Aerobic exercise induces the formation of neuroprotective irisin in the brains of mice

The new study took a three-pronged approach to investigate the role of irisin. In the first phase, the researchers acquired samples of cerebral tissue from human brain banks for analysis.

Post-mortem tissue evaluations showed that irisin molecules travel to the hippocampus, the region of the brain responsible for storing memories. Furthermore, the brains of patients with Alzheimer's disease have much lower concentrations of irisin in the hippocampus, which is a prime target of the neurodegenerative disease.


In the second phase, the researchers set up a mouse model and tested the ability of irisin to rescue the plasticity of synapses that connect neurons. They also evaluated the hormone's ability to preserve memory in the animals.

During this phase, the researchers deliberately disabled irisin in the brains of mice. They found that low levels of the hormone weakened both memory and synaptic function. On the other hand, increasing the levels of irisin in the brain improved the performance of the synapses and enhanced memory.

The third phase focused on the influence of aerobic exercise on irisin concentrations in the brain of mice.  The researchers made the animals swim for 60 minutes five days each week. Meanwhile, they designated another group of mice that did not swim regularly as the control.

The researchers reported that, compared with the control group, the group which swam regularly produced detectable amounts of irisin, proving that irisin production is linked to exercise.

Irisin improves memory and may protect against Alzheimer's disease

As part of their experiment, the researchers also infused beta-amyloid protein into the brains of the swimming group. The buildup of beta-amyloid plaques in the brain is linked to the onset of Alzheimer's disease.

The researchers found that the presence of exercise-induced irisin protected brain neurons against the harmful effects of beta-amyloid. When they administered a pharmaceutical drug that disables irisin to the animals, the mice lost the neuroprotective benefits they got from swimming. Similarly, irisin improved the memories of mice that swam often, but irisin-blocking drugs erased this improvement based on memory tests.

The results of the three-pronged study indicated that exercise-induced irisin offers protection against Alzheimer's disease and other forms of dementia. The study was published in the journal Nature Medicine.

"In the meantime, I would certainly encourage everyone to exercise, to promote brain function and overall health," said Columbia University researcher Ottavio Arancio, a co-author of the study.

"But that's not possible for many people, especially those with age-related conditions like heart disease, arthritis, or dementia."

That's why for their next study, Arancio and his colleagues are planning to investigate possible drugs that can increase the levels of irisin in the brain without the need for exercise.

Sources include:

Take Action:
Support Natural News by linking to this article from your website.
Permalink to this article:
Embed article link:
Reprinting this article:
Non-commercial use is permitted with credit to (including a clickable link).
Please contact us for more information.
Free Email Alerts
Get independent news alerts on natural cures, food lab tests, cannabis medicine, science, robotics, drones, privacy and more.
App Store
Android App
eTrust Pro Certified

This site is part of the Natural News Network © 2022 All Rights Reserved. Privacy | Terms All content posted on this site is commentary or opinion and is protected under Free Speech. Truth Publishing International, LTD. is not responsible for content written by contributing authors. The information on this site is provided for educational and entertainment purposes only. It is not intended as a substitute for professional advice of any kind. Truth Publishing assumes no responsibility for the use or misuse of this material. Your use of this website indicates your agreement to these terms and those published here. All trademarks, registered trademarks and servicemarks mentioned on this site are the property of their respective owners.

This site uses cookies
Natural News uses cookies to improve your experience on our site. By using this site, you agree to our privacy policy.
Learn More
Get 100% real, uncensored news delivered straight to your inbox
You can unsubscribe at any time. Your email privacy is completely protected.