Autophagy: Eat Your Heart Out with Exercise

February 20, 2012

Autophagy:  Eat Your Heart Out with Exercise 

 Reference: Economist Jan 21, 2012, Nature Beth Levine, MD 

 Autophagy is a hot topic out there in the anti-aging world.  It literally means, “eating oneself” which sounds a bit gruesome.  But that’s it in a nutshell. And exercise makes you do more of it.  It’s the details that are interesting. Dr. Levine and her team from Texas Southwestern explored how autophagy works in mice by manipulating their autophagy genes, and making them with a green-glowing fluorescence.  Then, they got the mice to exercise.  

What they found was that the more the mice ran on a treadmill, up to 80 minutes a day, the more autophagosomes they developed.  An autophagosome is a structure that forms around parts of your cells and body that are used up and need to be recycled.  It envelopes those parts and digests them, sort of a recycling feature.  Having more autophagosomes is a good thing.  And the more your exercise, the more you have, up to the peak of 80 minutes a day in mice. 

 Now, the interesting part.  The researchers got a second strain of mice that couldn’t make autophagosomes in response to exercise.  Compared to the mice with the ability to increase the number of their autophagosome, the altered mice were less able to develop endurance to exercise and more likely to become glucose resistant.  That suggests that the process of autophagy is central to the process of preventing degenerative, aging illnesses.  

Fascinating! We know that exercise increases your ability to resist diabetes.  It also decreases dramatically your risk for cognitive decline and improves many markers of inflammation.   Your chance of dying from all causes drops as much as 50% in age-matched groups over 60 years old when you walk just 2 miles a day.  If you have sore knees and aching backs, exercising gets you better, not worse.  The phrase, “use it or lose it” comes to mind but this offers a whole new twist.   

When you exercise, you turn on your autophagy mechanisms, you boost your number of autophagosomes and you reprocess all your old used up parts.  So you “lose” your old, dead, used up parts and rebuild new parts.  So, “losing it” makes you regrow it! This research doesn’t prove that exercise helps you live longer.  What it gives is a plausible mechanism for why exercise is so unbelievably good for you.  We can’t genetically modify humans with glowing autophagosomes.  Something about ethics. But we sure can encourage you to get yourself out there and walk a mile or two. 

 WWW. What will work for me?  I’ve got this image of a Pac-Man gobbling up all my rotten used up parts when I jog.  Maybe that’s why I feel so good when I do it.  On vacation last week, I had the lovely experience of passing a jogger who must have been in her eighties. She smiled and flashed a V for victory to me.   Fellow exercisers unite! 

Pop Quiz

1.   What is autophagy?              Answer: the structured dismantling of senescent cells and cellular elements. (junk). Aka, recycling.

2.   What happens to your natural autophagy when you exercise?                   Answer: It increases dramatically.

3.    With an increase in autophagy, what is then observed is an improvement in glucose control.

4.    Can you show that exercise makes humans live longer?                Answer: that's easy to do.   The increase in autophagy is a plausible explanation how.

 Written by John E Whitcomb, MD  Brookfield Longevity and Healthy Living Clinic, 17585 W North Ave, Suite 160   Brookfield, WI 53045   262-784-5300