What Is Myostatin?

Myostatin is a secreted protein that acts as a negative regulator (inhibitor) of skeletal muscle growth. Myostatin is a member of the transforming growth factor beta (TGF-B) superfamily of growth factors and is technically referred to as growth and differentiation factor 8 (GDF-8). Myostatin actually inhibits the growth of skeletal muscle by downregulating almost every myogenic (muscle building) factor known to induce skeletal muscle growth. Myostatin also influences special stem cells known as satellite cells away from myogenesis (the formation of new muscle cells) and toward adipogenesis (the formation of new fat cells). Myostatin is almost certainly the most powerful repartitioning substance that is produced in mammals and methods that will be used to suppress this protein will change the world forever.



Cattle with a myostatin deficiency accumulate an impressive amount of muscle tissue.



Myostatin And Humans

Have you ever seen a muscular individual that can eat whatever they want and not get fat? Are you envious that this person doesn't even have to exercise to look the way they do? Chances are this person was born with some form of myostatin deficiency. The myostatin protein was only discovered in 1997 and the identification of individuals with a deficiency of this protein has not occured until recently. While there are certainly many individuals that possess a myostatin deficiency there are only a few cases where a myostatin mutation has been detected in humans. The infant in the photo below is one of them.



An unidentified German male infant with a myostatin deficiency.

This child will grow up and possess enhanced skeletal muscle mass and super endurance. It is probable that many professional athletes today possess some form of a myostatin deficiency that allows them to excel in their chosen sport. Obviously not everyone was fortunate enough to be born with a myostatin mutation, however the future holds promise for a number methods to suppress myostatin and provide numerous benefits for those that undertake one these therapies.

Myostatin And Obesity

Americans spend billions and billions each year on ways to lose weight. Weight-loss drugs and supplements, special diets, and even surgical interventions (liposuction and gastric bypass) are utilized in an attempt to win the battle of the bulge. As I mentioned earliar the suppression of myostatin can induce a powerful repartitioning effect away from fat deposition and towards skeletal muscle accretion even in animals fed a high fat diet. Once an effective method for controlling myostatin is made available to the public the weight loss industry will go bankrupt. No more weight-loss pills, no more weird diets and no more expensive surgeries will accompany this revolution. This is not an exagerration, true myostatin suppression will make these measures obsolete. Some of you (especially women) may be concerned that too much muscle will be gained by using a myostatin inhibitor. This is not likely to be an issue as there will be a means to modulate and not eliminate myostatin activity.



Myostatin suppression and other future therapies will make obesity a thing of the past.



Myostatin And Muscle

By now it should be clear that myostatin suppression will induce skeletal muscle growth, but at this point I want to clear up a popular misconception. When I attempt to describe the benefits of myostatin suppression to anyone the inevitable comparison to anabolic steroids is made. You can think of an anabolic steroid like testosterone as the "gas" and the myostatin protein as the "brake" in relation to skeletal muscle growth. Anabolic steroids are able to enhance skeletal muscle growth because they overcome the inhibitory influence of myostatin on this process. The reason that myostatin suppression is an effective method for building new skeletal muscle is because you body produces it's own growth factors (testoterone, estrogen, Insulin, GH, IGF-I, HGF, FGF, IL-4, IL-15, PGF2a, others) and with no "brake" (growth arrest) in place these growth factors can proceed uninhibited. A major difference between anabolic steroid administration and myostatin suppression boils down to the side effects. Anabolic steroids induce numerous side effects while myostatin inhibition appears to be largely void of any serious side effects. Myostatin suppression therapy will be sought after by a large percentage of American men (almost all of them) that want to develop a lean muscular body with little or no exercise. Women will also want the benefit of added strength and muscle mass that accompanies this therapy and modulation of myostatin activity will be able to prevent gross muscle hypertrophy in females that seek this treatment.





Few people have the potential to build muscle like Arnold. Myostatin suppression therapy will help change that.



Myostatin And Disease

At this point in time all the research on myostatin suppression is focused on the treatment of muscle wasting diseases. Muscular dystrophy, AIDS, sarcopenia, cancer cachexia, and other states where extreme skeletal muscle breakdown is an issue could in part be treated through myostatin inhibition. Suppression of the myostatin protein will not only help improve our appearance, it will actually save lives. There are numerous diseases that will benefit from myostatin inhibition and in fact this will be one of the biggest markets for this type of therapy.



Myostatin suppression therapy will help patients recover from potentially fatal muscle wasting diseases.



Myostatin Suppression Therapies

Now that the benefits of myostatin suppression are understood the question is how best to inhibit the activity of this protein. There are a number of supplements that claim to be myostatin inhibitors, but in reality all of these products are a scam and have never demonstrated an in vivo ability to inhibit myostatin. It may be that true myostatin suppression is only possible with the development of drugs designed for this purpose. At this time there are three pharmaceutical corporations that are developing these specific myostatin inhibitors, Acceleron Pharma Inc, Amgen, and Wyeth Pharmaceuticals.





Myostatin control will allow men and women to shed fat and build muscle.



Acceleron Pharma has produced a powerful myostatin inhibitor based on ACVR2B. The designation given to this drug is ACE-031, the first in a series of myostatin inhibiting substances that this company is working on. Mutant activin type II receptors inhibit myostatin activity and ACE-031 utilizes this pathway to suppress myostatin.



Amgen is developing AMG 745, a peptide based drug designed to bind with and suppress the activity of myostatin. AMG 745 may be similar to the myostatin propeptide. The myostatin propeptide is produced in the body and binds with myostatin thereby reducing the availability of the protein to available receptors.



Wyeth pharmaceuticals has developed MYO-029, an antibody that binds to and inhibits myostatin activity. The Wyeth myostatin antibodies should be approved in the near future for use in patients with muscular dystrophy.



An actual vaccine has been produced that would allow for the endogenous production of antibodies that inhibit myostatin. A myostatin vaccine may never be used in humans but it would be wildly popular with those individuals that raise livestock for a living. Click the link below for an abstract about the myostatin vaccine.


Follistatin and follistatin related gene (FLRG) are two other proteins that are produced by the body that also bind with myostatin and act as inhibitors of the protein. While there is no question that follistatin and FLRG act as endogenous myostatin inhibitors, the overexpression of these two proteins has been associated with reproductive organ abnormalities in both males and females. This may be the reason that these companies are not pursuing the development of myostatin suppressing drugs that based on these two proteins.



The future of myostatin suppression therapies

The myostatin inhibiting therapies that are being developed, as mentioned before, are for those that are suffering from a disorder that affects the development of skeletal muscle or for those experiencing an illness that induces skeletal muscle wasting. It is not likely that the FDA will approve these drugs for cosmetic enhancement (fat-loss and muscle accretion) anytime soon. However, effective myostatin inihibiting therapies will be sought after as soon as the public becomes aware of how these therapies can improve their body composition. If the American public is denied these therapies for cosmetic use by th FDA then a lucrative black market will emerge to fill the demand. Other nations in the world will not have to grapple with this issue, as these therapies will receive quick approval for the cosmetic use of these drugs. It is inevitable that the widespread availability of these drugs in other countries will make it easier for Americans to obtain these myostatin inhibitors via mail order. Independant individuals and companies will also cater to this black market demand. The genie is out of the bottle and he's not going back in. Every now and then a technology comes along that has a ripple effect on multiple industries and the various myostatin inhibiting therapies is one such technology. The revolution is about to begin.