Exercise delivers a litany of benefits for the body and brain, but exactly how is a mystery yet to be solved. Researchers investigating the benefits of exercise may have found an important clue: a hormone called “Irisin” triggered by exercise that turns ordinary fat into brown fat, which vigorously burns calories even at rest. Irisin also appears to make the body more sensitive to glucose, a key to preventing the onset of diabetes.
Drilling down into the benefits of exercise
Scientists have known that secretion of a beneficial protein in the body called PGC1-alpha is triggered by exercise. In an effort to learn more about how and why PGC1-alpha promotes resistance to metabolic diseases, a team of scientists from the Dana Farber Cancer Institute in Boston discovered a new hormone hidden inside a complex molecule of PGC1-alpha.
The hormone sends a signal to the body that stimulates the production of energy-burning brown fat. Researchers christened the new hormone Irisin, after the Greek messenger goddess Iris for its ability to send information to surrounding body tissue.
Irisin and exercise (or not)
In the study, Irisin levels in the body remained high long after exercise sessions had concluded. People who underwent 10 weeks of endurance training had twice the Irisin in their blood than sedentary people. Mice in the laboratory on a three-week treadmill regimen had Irisin levels 65 percent higher than unexercised mice.
After observing those results, the researchers wondered if Irisin alone could generate exercise benefits minus the physical activity. So they injected obese mice on a high-fat diet that were on the verge of diabetes with the amount of Irisin they would produce from a daily workout. After 10 days, the mice actually lost a little weight and gained glucose sensitivity. Later, the mice were dissected and no ill effects from the jolt of Irisin were found.
A future treatment for obesity and diabetes prevention?
Although the weight loss was small, the researchers speculate that a daily dose of Irisin should result in greater weight loss and glucose sensitivity over longer periods. It’s common knowledge that obesity and diabetes are major health problems. A sedentary lifestyle has also been identified as a risk factor for cancer. Because it’s a natural substance, identical in both mice and humans, Irisin-based drugs could be used to help treat a variety of metabolic diseases in the near future.
The researchers are now investigating the effects of Irisin on other diseases, including neurodegenerative conditions like Parkinson’s disease. Their findings have been licensed to a pharmaceutical company for development of an Irisin-based drug.
Don’t cancel your gym membership
But if Irisin is proven a safe supplement for humans in clinical trials, it will never be a replacement for your gym membership. Irisin injections did not increase muscle mass for the mice in the study. And a significant increase in Irisin levels is only evident after consistent and prolonged exercise in humans. But it might help at risk people fight off obesity, retain glucose sensitivity and prevent diabetes.
Source: Scientific American, Medical News Today, New Scientist