GDF-8 (Myostatin)
Your body's built-in limit on muscle size. Myostatin is the protein that tells your muscles 'stop growing' — it's the brake, not the accelerator. Included here because it's the target that drugs like follistatin and ACE-031 try to block. When this protein doesn't work (due to genetic mutations), the result is extraordinary muscle development — seen in certain cattle breeds, racing dogs, and at least one documented human case. Blocking myostatin is one of the most researched goals in muscle science.
Dosage
Not administered therapeutically — research reagent only
Dosages shown are for research reference only. Always consult a qualified healthcare provider.
Administration
Not applicable (research reagent)
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Mechanism of Action
Myostatin (GDF-8) is a secreted TGF-beta superfamily member that serves as the body's primary negative regulator of skeletal muscle mass. It is predominantly expressed by skeletal myocytes and secreted into the circulation as a latent complex bound to its propeptide. Activation requires proteolytic cleavage by BMP-1/tolloid metalloproteases, which release the mature myostatin dimer for receptor engagement.
Active myostatin binds to the activin type IIB receptor (ActRIIB) on the surface of muscle cells and satellite cells. This triggers recruitment and phosphorylation of the type I receptor ALK4 or ALK5, which in turn phosphorylates the intracellular signaling molecules Smad2 and Smad3. Phosphorylated Smad2/3 forms a complex with the common mediator Smad4, and this trimeric complex translocates to the nucleus where it directly suppresses the transcription of key myogenic regulatory factors including MyoD, Myf5, myogenin, and MRF4. The suppression of these transcription factors inhibits both satellite cell differentiation (preventing the formation of new myonuclei) and muscle protein synthesis in existing myofibers.
Myostatin also activates the ubiquitin-proteasome pathway through FoxO transcription factors, upregulating the muscle-specific E3 ubiquitin ligases atrogin-1/MAFbx and MuRF1, which tag muscle proteins for degradation. Additionally, myostatin signaling inhibits the Akt/mTOR pathway, further suppressing protein synthesis. The combined effect is a powerful dual mechanism: simultaneously reducing protein synthesis and increasing protein degradation, creating a strongly catabolic environment. The biological importance of myostatin is dramatically demonstrated by natural loss-of-function mutations — Belgian Blue cattle, Piedmontese cattle, whippet dogs, and at least one documented human case all show extraordinary muscle hypertrophy when myostatin is absent or non-functional. This has made myostatin inhibition one of the most actively pursued therapeutic targets for muscle wasting diseases.
Regulatory Status
Not a therapeutic agent. Sold as a research reagent/protein. Myostatin inhibitors (antibodies, traps) are in clinical development for muscle wasting diseases.
Risks & Safety
Serious
exogenous myostatin administration would inhibit muscle growth and promote muscle wasting. Not intended for self-administration.
Compare GDF-8 (Myostatin) With
Research Papers
30Published: January 14, 2025
AI Summary
Serum irisin and myostatin were linked to COVID-19 severity. The work explores how these muscle-derived signals may influence inflammation and metabolism during SARS-CoV-2 infection.
Published: February 4, 2026
AI Summary
A gene assay showed that five cattle myostatin variants do not affect RNA splicing, unlike a known intronic variant. SpliceAI and Pangolin predicted effects matched the assay, supporting their use for screening before lab validation.
Published: January 28, 2026
AI Summary
Soft diets raised myostatin and lowered IL-6 and IL-10 in jaw muscle, reducing muscle size and increasing fat. Adequate chewing during growth appears important for muscle development and metabolic health.
Published: January 12, 2026
AI Summary
CRISPR-Cas9 was used to edit the myostatin gene in swimming crab zygotes. The work establishes genome editing in this species and could support genetic improvement of aquaculture stocks.
Published: January 17, 2026
AI Summary
Myostatin links obesity to muscle and tendon damage through fibrosis and fat accumulation. Restoring normal myostatin levels may help reverse tissue breakdown and improve mechanical function in obesity.
Published: January 14, 2026
AI Summary
NCAPG and MSTN mutations both increased muscle and reduced fat in cattle, but each affected different traits. The work clarifies how these genes shape carcass composition and meat quality.
Published: January 23, 2026
AI Summary
GLP-1 and dual GLP-1/GIP drugs cause substantial lean muscle loss. Myostatin inhibitors, SARMs, and siRNA therapies may help preserve muscle, but more trials with body composition and functional outcomes are needed.
Published: April 7, 2025
AI Summary
Teens with long-standing type 1 diabetes had lower apelin and higher myostatin linked to insulin dose and blood pressure. These myokines may reflect beta-cell function and insulin sensitivity in T1D.
Published: January 19, 2026
AI Summary
Liraglutide's early effects on body composition and circulating muscle and bone regulators like myostatin, activin, follistatin, and IGF-1 were assessed in a crossover trial. The work clarifies how GLP-1 drugs affect muscle and bone metabolism in the first weeks of treatment.
Published: February 15, 2026
AI Summary
The link between sarcopenia and cognition in older adults was explored, with irisin, BDNF, myostatin, and IGF-1 as possible mediators. The work tests whether myokines help explain the muscle-brain connection.
Published: February 27, 2026
AI Summary
Peptides from digested chicken breast blocked ActRIIB, reduced myostatin signaling, and boosted muscle cell growth. These peptides could serve as functional food ingredients for muscle-wasting conditions.
Published: December 11, 2025
AI Summary
Feed composition changed myostatin and myogenic gene expression in rainbow trout muscle, especially in smaller fish. Diet influences muscle growth regulation during early development.
Published: January 2, 2026
AI Summary
Carnosine reduced muscle protein loss at high altitude by lowering myostatin, raising IGF-1, and improving antioxidant and protein balance. Carnosine supplementation may help prevent altitude-related muscle wasting.
Published: December 19, 2025
AI Summary
Myokines like myostatin and irisin link inflammation to insulin resistance across muscle, fat, liver, and other organs. Preserving muscle mass through exercise should be a core target in metabolic and thyroid disease.
Published: January 6, 2026
AI Summary
Short-term liraglutide changed the blood proteome in a crossover trial; results were compared with published semaglutide data. The work clarifies systemic protein mechanisms of GLP-1 drugs.
Published: January 8, 2026
AI Summary
Beyond bone, denosumab may influence muscle by modulating inflammation, myostatin, and insulin sensitivity via RANK/RANKL/OPG. The review summarizes evidence for muscle-related effects of this osteoporosis drug.
Published: June 3, 2026
AI Summary
A peptide (BV2) targets blood vessel epicardial substance and delivers drugs to skeletal and cardiac muscle. BV2-anti-myostatin increased muscle mass in atrophy models and improved dystrophin restoration in DMD mice.
Published: December 16, 2025
AI Summary
Myokines like myostatin, IL-6, and irisin regulate muscle mass, metabolism, and immunity, and their release can vary by muscle fiber type. Understanding this may support new therapies for metabolic and regenerative medicine.
Published: January 1, 2026
AI Summary
Luspatercept and sotatercept trap activin and related ligands at type II receptors and are approved for anemia and pulmonary hypertension. They have not consistently increased muscle mass in trials but represent advances in blood and vascular disease.
Published: December 28, 2025
AI Summary
Blocking myostatin, including with antibodies and follistatin-based approaches, increases muscle mass and function in preclinical and early clinical studies. The review outlines how these therapies could address age-related muscle loss and the hurdles to bringing them to patients.
Published: November 25, 2025
AI Summary
Lipophilic siRNAs silenced myostatin in muscle for months with a single dose, increasing lean mass and grip strength. Biweekly dosing maintained strong silencing for half a year, offering a durable option for muscle-wasting disorders.
Published: November 29, 2025
AI Summary
Myostatin inhibitors may offset muscle loss from GLP-1 drugs and are being tested alone and with GLP-1 analogs for obesity and diabetes. The review discusses their emerging role in metabolic disorders.
Published: November 30, 2025
AI Summary
GLP-1 agonists can protect muscle in animal models by boosting myogenic factors and suppressing myostatin, but human trials show weight loss with lean mass loss. Low-dose GLP-1 may be useful in sarcopenic obesity if combined with strategies to preserve muscle.
Published: January 31, 2026
AI Summary
Myostatin-mutant cattle reached final pH sooner and had higher histone crotonylation and glycolysis-related gene expression during aging. The findings clarify meat quality changes in double-muscled beef.
Published: November 27, 2025
AI Summary
Organokines like myostatin, FGF-21, and irisin link the liver to muscle, fat, and other organs in fatty liver disease. Targeting these signals could yield new biomarkers and treatments for MASLD.
Published: March 7, 2026
AI Summary
Fermented mealworm extract reduced bone and muscle loss after ovary removal by modulating RANKL-NF-kB/MAPK and IGF-1-PI3K-Akt, and by suppressing myostatin. It may help treat postmenopausal osteoporosis and muscle atrophy together.
Published: December 9, 2025
AI Summary
The first myostatin-knockout buffalo was produced via CRISPR-Cas9 and cloning. The calf showed faster growth and more muscle fibers with normal meat composition, demonstrating the approach for livestock improvement.
Published: December 7, 2025
AI Summary
In aged female rats, HIIT raised muscle follistatin more than resistance training, while resistance training raised myostatin more. HIIT may be a better option for older adults aiming to improve the follistatin-myostatin balance.
Published: February 1, 2026
AI Summary
Head and neck tumors produce myostatin, activin-A, and follistatin, which may drive muscle loss in cancer. The exploratory study links these factors to sarcopenia in HNC patients.
Published: January 25, 2026
AI Summary
Editing myostatin and Callipyge in goat cells showed crosstalk between the two genes in muscle growth. MSTN knockout strongly upregulated myosin genes; TRIM28 may be involved in Callipyge regulation.
Frequently Asked Questions
What is GDF-8 (Myostatin)?
Your body's built-in limit on muscle size. Myostatin is the protein that tells your muscles 'stop growing' — it's the brake, not the accelerator. Included here because it's the target that drugs like follistatin and ACE-031 try to block. When this protein doesn't work (due to genetic mutations), the result is extraordinary muscle development — seen in certain cattle breeds, racing dogs, and at least one documented human case. Blocking myostatin is one of the most researched goals in muscle science.
What is GDF-8 (Myostatin) used for?
Your body's built-in limit on muscle size. Myostatin is the protein that tells your muscles 'stop growing' — it's the brake, not the accelerator. Included here because it's the target that drugs like follistatin and ACE-031 try to block. When this protein doesn't work (due to genetic mutations), the result is extraordinary muscle development — seen in certain cattle breeds, racing dogs, and at least one documented human case. Blocking myostatin is one of the most researched goals in muscle science.
What is the dosage for GDF-8 (Myostatin)?
Not administered therapeutically. Research reagent only — used for binding assays, antibody development, and in vitro screening of myostatin inhibitors. The therapeutic goal is to inhibit or block myostatin, not supplement it.
What are the side effects of GDF-8 (Myostatin)?
Serious: exogenous myostatin administration would inhibit muscle growth and promote muscle wasting. Not intended for self-administration.
How does GDF-8 (Myostatin) work?
Myostatin (GDF-8) is a secreted TGF-beta superfamily member that serves as the body's primary negative regulator of skeletal muscle mass. It is predominantly expressed by skeletal myocytes and secreted into the circulation as a latent complex bound to its propeptide. Activation requires proteolytic cleavage by BMP-1/tolloid metalloproteases, which release the mature myostatin dimer for receptor engagement. Active myostatin binds to the activin type IIB receptor (ActRIIB) on the surface of muscle cells and satellite cells. This triggers recruitment and phosphorylation of the type I receptor ALK4 or ALK5, which in turn phosphorylates the intracellular signaling molecules Smad2 and Smad3. Phosphorylated Smad2/3 forms a complex with the common mediator Smad4, and this trimeric complex translocates to the nucleus where it directly suppresses the transcription of key myogenic regulatory factors including MyoD, Myf5, myogenin, and MRF4. The suppression of these transcription factors inhibits both satellite cell differentiation (preventing the formation of new myonuclei) and muscle protein synthesis in existing myofibers. Myostatin also activates the ubiquitin-proteasome pathway through FoxO transcription factors, upregulating the muscle-specific E3 ubiquitin ligases atrogin-1/MAFbx and MuRF1, which tag muscle proteins for degradation. Additionally, myostatin signaling inhibits the Akt/mTOR pathway, further suppressing protein synthesis. The combined effect is a powerful dual mechanism: simultaneously reducing protein synthesis and increasing protein degradation, creating a strongly catabolic environment. The biological importance of myostatin is dramatically demonstrated by natural loss-of-function mutations — Belgian Blue cattle, Piedmontese cattle, whippet dogs, and at least one documented human case all show extraordinary muscle hypertrophy when myostatin is absent or non-functional. This has made myostatin inhibition one of the most actively pursued therapeutic targets for muscle wasting diseases.
How is GDF-8 (Myostatin) administered?
GDF-8 (Myostatin) is administered via not applicable (research reagent).
What is the half-life of GDF-8 (Myostatin)?
The half-life of GDF-8 (Myostatin) is 12 hours.
Is GDF-8 (Myostatin) legal?
Not a therapeutic agent. Sold as a research reagent/protein. Myostatin inhibitors (antibodies, traps) are in clinical development for muscle wasting diseases.
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