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Newly Discovered Hormone Boosts Effects of Exercise, Could Help Fend Off Diabetes

The views expressed are those of the author and are not necessarily those of Scientific American.

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Hormones aren’t just for sex—they help control everything from the times when we feel hungry to the timing of our heart beats. Dozens have been described, but there is now a new one on the scene. It might help explain some of the health benefits of exercise and point the way to preventing obesity and diabetes. The find was described online Wednesday in Nature (Scientific American is part of Nature Publishing Group).

Exercise has myriad benefits for the body and brain, but many of the triggers for these improvements have so far been somewhat of a mystery.

“There has been a feeling in the field that exercise ‘talks to’ various tissues in the body,” Bruce Spiegelman, a cell biologist at Dana-Farber Cancer Institute and co-author of the new study, said in a prepared statement. “But the question has been, how?”

Speigelman and his colleagues found that exercise—in both mice and humans—starts a cascade of signaling changes, including the production of a never-before-described hormone. They dubbed the new hormone irisin, as a nod to the Greek messenger goddess Iris for its ability to send information to surrounding body tissue.

And the messages irisin carries are not trivial—they seem to effect positive changes in the body. An increase in irisin helps turn white fat into the more beneficial and metabolically active brown fat, which burns more calories. It also seems to make the body more sensitive to glucose, an important capability for keeping diabetes at bay.

In the study, the researchers discovered that exercise increases the body’s production of a metabolism-regulating protein, which in turn stimulates expression of a protein that can produce the new hormone, found to reside in the outer membranes of muscle cells.

The effects of exercise on the hormone’s production seem to be long-lived. Even after 12 hours of rest, mice that had been on a three-week jogging regimen had 65 percent more irisin in their blood than unexercised mice. And people who had gotten 10 weeks of endurance exercise training had double the amount of irisin in their blood than those who had not.

But could this hormone, the scientists wondered, mimic some of the effects of exercise—without subjects having to hit the treadmill? To find out, they injected a batch of obese, pre-diabetic mice that had been fed a high-fat diet with just about as much of an irisin boost as they would get from a workout. After 10 days of injections, the irisin-boosted mice had shed a little weight and become more sensitive to glucose—all without exercise. And a later dissection showed that the hormone spike didn’t seem to have any negative biological effects.

“It is likely that irisin is responsible for at least some of the beneficial effects of exercise on the browning of adipose tissues and increase in energy expenditure,” Speigelman and his colleagues noted in their paper. This find might help explain some of the “afterburn” of extra calories after vigorous activity.

Even if the hormone proves safe for humans to take as a supplement, it won’t replace all the benefits of going to the gym. But it might help people fight obesity and remain more sensitive to glucose, thus fighting off diabetes.

“It’s exciting to find a natural substance connected to exercise that has such clear therapeutic potential,” Pontus Bostrom, a postdoctoral researcher at Dana Farber and co-author on the new paper, said in a prepared statement. The researchers are now also investigating possible effects of the exercise-based hormone on other diseases, including neurodegenerative conditions, and have licensed the finding to Ember Therapeutics (a company co-founded by Spiegelman) for drug development.

Katherine Harmon Courage About the Author: Katherine Harmon Courage is a freelance writer and contributing editor for Scientific American. Her book Octopus! The Most Mysterious Creature In the Sea is out now from Penguin/Current. Follow on Twitter @KHCourage.

The views expressed are those of the author and are not necessarily those of Scientific American.

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  1. 1. PrettyOld 2:44 pm 01/11/2012

    The food was changed in the USA, UK and Australia 30 years ago when dangerous food chemicals from the USA was allowed into European. The food today causes stubborn insulin If you have stubborn insulin you hold fat and have a hard time losing weight.

    You can eat very little and the weight still does not come off. Stubborn insulin will hold fat and diets won’t work. When researchers used a specialized diabetes diet on overweight people all lost weight eeven those who did not have diabetes. The diet proved food chemicals are why dieting does not work.

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  2. 2. doc 2:53 pm 01/11/2012

    Now we have a new pill to reduce weight. It appears that we will soon have a pill for all our shortcomings. We can forget about positive life style changes and self control. Good idea to invest in the pharmaceutical industry.

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  3. 3. sidelight 8:59 pm 01/11/2012

    Wonderful, all seek the highly marketable supplement to do what essentially free proper diet and exercise do. We seek to erase natural human life and replace with a construct. Here’s what you’ll get. Fat, sick and dying populations who are trained to just slide down the slope to atherosclerotic diabetic decline, morbidity and early death, in exchange for non-cure treatments with snake-oil like Lipitor, and tongues and stomachs accustomed vast over consumption of sugars, starches and fats.

    The competitive, and lean will dance on their graves, but for the cost burden of caring for these slow suicides, and the grief that many are our own families.

    Note that 3/4 of the human race does not suffer from significant atherosclerosis and diabetes. They can’t afford the rich man’s diseases.


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  4. 4. Unksoldr 11:48 pm 01/11/2012

    How about they get off their lazy butts and exercise. Which will increase the hormone naturally and keep your money out of pharma’s pocket. Doctor’s tell me I’m diabetic, until I lost 50lbs and started exercising regularly I was. Now, I take no meds and my fasting blood glucose is normal but I’m still considered a diabetic, go figure.

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  5. 5. bferrazd 12:45 pm 01/12/2012

    (Spiegelman’s name is at places misspelled as Speigelman)

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  6. 6. jafrates 3:10 pm 01/12/2012

    @PrettyOld: What is “stubborn insulin”? Is it chemically different from the link’s “sensitive insulin”? I suspect that while the effects may be real, there are no studies backing these labels.

    The dismissive attitudes here are dismissing other serious examples of diabetes. I had a friend growing up who needed insulin injections by age 8. If this helps people like him reduce their need for insulin, it can go a long way toward improving their quality of life. My girlfriend’s family has a long history of Type 2 diabetes, and even though she is on a diabetes-specific diet, she still struggles with it.

    Perhaps we can keep the discussion civil instead of labeling people?

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  7. 7. karounos 3:25 pm 01/12/2012

    To all the people bashing the drug for being part of the ‘evil’ pharma system: what about patients that can’t exercise for health reasons other than the ‘rich man’s disease’ and obesity, such as a weak heart, a recent surgery, or even a severe disability i.e. amputations etc?

    Does a treatment that can mimic exercise in certain ways physiologically for someone that physically can’t exercise still sound pointless and excessive to you?

    You shouldn’t be so quick to criticize, of course unless I’m sure there’s some amazing science you’re doing that deserves this article’s place!

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  8. 8. gmperkins 4:03 pm 01/13/2012

    I am suprised that they just found irisin. Makes me wonder how many more ‘hidden’ hormones have yet to be discovered. As for some comments, why talk about lifestyle? This is a new and interesting finding. But instead of talking about it, some of you feel compelled to discuss how everyone should be just like you, even if they are born with juvenile diabetes or crippled in an accident.

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  9. 9. MissLucy 11:08 pm 01/15/2012

    You know I am really sick of all of these so called exercise goo-roos that say stuff that they don’t know anything about. Like disabled plus size people that cannot go and exercise like you. We have to take pain medicine so we can walk aross the room. I have an autoimmune disease that is called Mixed Connective Tissue disease. It has alot of diseases mixed up in that one name. I have had to have a stent put into my heart I am looking at knee replacement,hip replacement, I had to have my thyriod removed. I can’t explain to you how hard it is to live everyday with this weight and pain. So I heard about this pill that might help a little with losing weight. I look it up at this site and started reading I was really encouraged then I look down at the comments I stated crying, then I decided that all of you that are saying such bad stuff about us overweight people you really did not know how it fells and what we go through. I use to weigh 115 lbs for years. And was active. Then I got sick. I now weigh enough that anything out there that can help I read and hope. Just know if I have changed anyone of your minds out there that thought so bad about us overweight people well then all of this pain I have gone through by sitting here and typing is worth it.

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  10. 10. bigfish344 7:56 pm 01/18/2012

    As a lifelong physical educator and both recreational and competitive runner, I believe profoundly in the benefits of exercise and there is no doubt in my mind that we should all take part in some form of daily exercise routine. We should also see that all of our kids receive a quality, daily period of physical education in their school. Having said that, I support anything that will help people overcome diabetes and it’s attendant infirmatives. As people lose weight, as their general health improves then they are initiate or build on an exercise program that helps continue the cycle of improving health. Throwing stones at people for various reasons or criticizing the pharmaceutical industry (which has earned a wealth of criticism)is non productive. If we’re going to take control of the health care system in this country, before it bankrupts us, dealing in proper fashion with overweight/obesity/diabetes/cardiovascular disease and stroke would be a pretty good place to start.

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  11. 11. bucketofsquid 12:51 pm 01/25/2012

    You have to forgive the spastic over exercisers because they have reduced body fat so low that the myelin sheathing is breaking down in their brains and they are becoming brain damaged.

    It is obviously better to exercise intensively every day but with modern civilization there is little need for that kind of activity level. The obvious solutions are – Genetic mutation to support reduced activity levels or alternatively, a more practical way of simulating the affects of exercise on the body. Unless you want to abandon technology those are the only options I see.

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  12. 12. Sinclairt1991 9:53 pm 02/15/2012

    @Miss Lucy,

    I can empathize that the world is cruel and there are a lot of people that spout off when they do not know what they are talking about. I am a 21 year old male in great health and am not disabled in any form at all. Therefore you are correct I can not begin to imagine what it is like to be over weight and feel the effects of obesity.

    However, I can tell you the effects that obesity can have on friends and family members, both my grandparent and parents are over weight, and as I child my concerns were, they are too old and overweight to play with me, and I spent a lot of time by myself wishing my parents could just get off the couch and spend time with me.

    Then as an adult my concerns became less about me and more about them, fearing for their health and wondering if they can live long enough to see their grandchildren grow up, and what my children’s experience will be, will they make the memories I was lucky enough to have with my grandparents.

    you mentioned finding a pill that will help you lose weight and you looked into it, due to your medical issues making it hard to exercise, this should never be an option, rather than reading the posts from insensitive people, start by reading the side affects and the possibilities of even more medical issues.

    I find it funny that most weight loss pills have as many or more possible harmful side affects than being over weight, you would be better off remaining overweight, when it boils down to it nothing beats good old fashion exercise.

    it may be hard and uncomfortable with having hips and knees replaced, however the remaining question is how long is that knee or hip going to last while you are beating it up by being overweight? it is best to start out small and work your way up.

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