It has been known for some years that naturally occurring mutations in the gene which controls myostatin results in double-muscling in cattle, dogs and even humans. Many in the body building community believe that blocking myostatin is a shortcut to the Arnold Schwarzenegger body.

The flipside is that producing too much myostatin has been linked with muscle wasting conditions such as HIV-AIDS, starvation and now, Type 2 diabetes.

Hittel believes this may be due to a pre-diabetic condition known as insulin resistance that "tricks" the muscles into thinking the body is starving despite the fact that blood sugar levels are skyrocketing.

"When that happens, the body reverses muscle production using myostatin," says Hittel. "This is particularly worrisome because losing muscle mass further erodes your ability to control your blood sugar with exercise."

One of the tell-tale signs of the transition between insulin resistance and full-blown Type 2 diabetes is a loss of muscle mass.

"Losing muscle mass makes sense from an evolutionary perspective since having large muscles during famine puts you at a serious risk for starvation," explains Hittel. "Unfortunately, this survival mechanism has left us ill-equipped to deal with a Western lifestyle-lots of calories, little exercise-and it has laid the groundwork for the current epidemic of Type 2 diabetes."

"The goal of my research is to understand how obesity, diet and exercise influence our metabolism and interact with our genome. This research sheds some light on an important part of the puzzle."

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Finally, Freund and Sherry injected IL-1RA antiserum into the obese animals an hour before exposing them to hypoxia.

"We expected the antibodies to bind all the IL-1RA so it couldn't affect recovery," she said. "And, sure enough, these animals didn't recover until 6 hours after the hypoxic event, basically the same pattern we saw with non-obese animals."

"So we were able to prove through several different mechanisms that in cases of obesity, there's a significant increase in the anti-inflammatory molecule IL-1RA, which helps animals recover from a traumatic loss of oxygen. The obese mice recovered faster because of the leptin-induced increase in IL-1RA," said Sherry.

Sherry repeated that obesity is a predisposing factor in many inflammatory conditions and encouraged people who are at a healthy weight to maintain that weight.

"However, obese persons do have about six times more circulating IL-1RA, which again is the anti-inflammatory molecule that aids recovery in oxygen-starved parts of the body," she noted.

"Once a health problem is established, there are certain conditions-congestive heart failure, rheumatoid arthritis, and other diseases that involve the utilization of oxygen-in which obese persons have been shown to have a better prognosis. And there is a legitimate discussion among physicians about how such patients should deal with their excess weight," said Freund.

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