First and foremost, myostatin is a myokine. Myokines are just one of hundreds of different types of cytokines, or small proteins. Cell signaling and commands are reliant on these smaller sized proteins. So, following along logically, myostatin is a protein that is inherently in charge of cellular signaling.
While myostatin is found in other animals as well, it’s located in the MSTN gene in human beings. The medical community has worked out enough of the Human Proteome Project to know that myostatin is a part of the TGF-β, or transforming growth factor beta, protein family. Unique from the other families of proteins, the TGF-β family is derived from white blood cells, exclusively.
Growth Differentiation Factor 8
Each myokine has an individual uniqueness and purpose. Myostatin is also know as the growth differentiation factor 8, or GDF-8. Growth differentiation factor proteins are those that directly influence development of cells in the body. Some may dictate muscle strength and cell growth while others can influence the strength of internal organs.
GDF-8, or myostatin, is specifically in charge of the cellular signaling that influences and dictates muscle mass. Note that mass and strength might be related but aren’t technically the same thing. GDF-8 has been the subject of many research projects over the past couple of decades, most of which revolve around the idea that GDF-8 supplementation can be leveraged to help humans or animals with naturally occurring deficiencies of myostatin.
Though GDF-8/myostatin was discovered in the ‘90s, it wasn’t until after the new millennium started that the medical community was able to understand what it was used for. In 2001, a team from the Genetics Institute in Cambridge, MA observed that GDF-8 did in fact “antagonize biological activity by inhibiting receptor binding.” The groundwork was laid for further myostatin observation and use case exploration. By the time 2010 rolled around, we were confident that myostatin was directly responsible for muscle mass growth. That’s when things got a little more heavy…
In September of 2010, a team from the Department of Cellular Biology and Anatomy of the Medical College located in Augusta, Georgia explored the possibility that myostatin could be leveraged to repair and regenerate muscle and bone after serious injury. The study’s results were largely conclusive, showing the potential that myostatin had when it came to improving wound repair. Surely this caught the attention of big pharmaceutical companies around the world.
More recent studies are more focused on the mechanisms of activation. Understanding exactly how the GDF-8 is activated within the system of an animal, or a human, will allow for streamlined application. Improving the speed of efficacy could theoretically speed the healing process in injured individuals. One of the most recent studies completed seems to have figured out the molecular characterization of latent GDF8, revealing the mechanisms of activation. This breakthrough is sure to transform the future of myostatin based medications and supplements forever.
1 “MSTN Gene – Genetics Home Reference – NIH.” U.S. National Library of Medicine, National Institutes of Health, https://ghr.nlm.nih.gov/gene/MSTN.
2 Thies, R S, et al. “GDF-8 Propeptide Binds to GDF-8 and Antagonizes Biological Activity by Inhibiting GDF-8 Receptor Binding.” Current Neurology and Neuroscience Reports., U.S. National Library of Medicine, 2001, www.ncbi.nlm.nih.gov/pubmed/11519824.
3 Hamrick, M W, et al. “Recombinant Myostatin (GDF-8) Propeptide Enhances the Repair and Regeneration of Both Muscle and Bone in a Model of Deep Penetrant Musculoskeletal Injury.” Current Neurology and Neuroscience Reports., U.S. National Library of Medicine, Sept. 2010, www.ncbi.nlm.nih.gov/pubmed/20173658.
4 Walker, R G, et al. “Molecular Characterization of Latent GDF8 Reveals Mechanisms of Activation.” Current Neurology and Neuroscience Reports., U.S. National Library of Medicine, 30 Jan. 2018, www.ncbi.nlm.nih.gov/pubmed/29348202.