Exercise In A Pill – Available Drugs Enhance Muscle Fibers Even Without Working Out – Salk Institute Research Study
(Best Syndication News) A new pill may give you the benefits of exercise without actually having to perform at the gym. Researchers are calling the drug, AICAR, the couch potato pill, and it is in the third phase of experimental trials. Another drug, GW1516, can enhance endurance when combined with exercise.
The “exercise in a pill” has been tested on mice with great results, according to Ronald Evans of the Salk Institute. "When we gave the mice a small amount of daily exercise in the presence or not of the drug, all showed an increased ability to run. But those on the drug gained an additional hour,” Evans said.
Currently the drugs are being developed for treating metabolic diseases, but some wonder if it could be used to treat obesity. Even without exercise, mice were “endowed” with endurance. The pills fooled the muscles.
"It's tricking the muscle into 'believing' it's been exercised daily," Evans said. "It's basically the couch potato experiment, and it proves you can have a pharmacologic equivalent to exercise."
The drugs tap into the molecular pathways that normally reprogram muscle in response to exercise. There are two types of skeletal muscle: Fast twitch and slow twitch. The fast twitch muscles burn sugar and help with quick runs, but slow twitch muscles burn fat and are used for endurance (like long runs).
In earlier experiments Evans and his colleagues were able to genetically engineer (or “pre-program”) juvenile mice to produce more slow-twitch muscle fibers. They did this by “ramping up” the activity of a gene in the muscle called PPARd. In adulthood, these untrained mice had much more endurance.
To see if they could re-program adult lazy mice, Evans gave them a drug called GW1516 which increased the activity of PPARd. "It was a spectacular failure," Evans said. "The drug by itself had no impact on running ability" even though there were changes in muscle gene activity.”
The scientists went back to the drawing board. They tested the drug on mice undergoing exercise training. After four weeks these mice were able to run 70 percent more than exercising-mice given the placebo.
This prompted them to try a drug called AICAR that works on the AMPK gene. Amazingly after four weeks, even the sedentary mice induced metabolic genes and enhanced running endurance by 44 percent. "We were blown away that AICAR alone mimicked exercise; not to the same level but a healthy boost," Evans said.
They concluded that either AICAR alone or GW1516 with exercise provided the desired result. "We believe that the strategy of re-organizing the preset genetic imprint of muscle (as well as other tissues) using exercise mimetic drugs has therapeutic potential in treating certain muscle diseases such as wasting and frailty as well as obesity where exercise is known to be beneficial."
As of July 31st, AICAR is in late stage human testing by Kenilworth, N.J.-based Schering-Plough Corp. to see if it can prevent a complication during heart bypass surgery. There has also been interest in using the drugs to treat high cholesterol and heart disease. There are human trials involved in that as well.
Both drugs are taken orally. Although the drugs are not yet approved for human use, they are readily available from laboratory supply companies. Toronto Research Chemicals Inc is selling AICAR for $120 a gram.
Athletic organizations are worried that the drugs could be used for muscle enhancement similar to steroids. Evans says that this is possible, but there is also the possibility that the drug can be used as a therapy. Patients that are bedridden or in a wheelchair would still be able to exercise. The drug may also be used to treat obesity, diabetes and muscle-wasting diseases such as muscular dystrophy.
The complete report is in the July 31 advance online edition of the journal Cell. See what others are saying and join the discussion at our Forum
By Jeffrey Workman
Best Syndication News Health Writer