WhatPeptide

Myostatin

The body's primary negative regulator of skeletal muscle mass — a TGF-β superfamily member encoded by the MSTN gene. Its amino acid sequence is 100% conserved across humans, mice, rats, chickens, and pigs. This is a research reagent, not a therapeutic; myostatin inhibitors (follistatin, trevogrumab) are the therapeutic approach.

Strong evidence Unregulated Growth Factor

Written by WhatPeptide Editorial Team · Last updated 2026-03-18

This is a research reagent, not a therapeutic compound. Myostatin is the biological target that inhibitors like follistatin, trevogrumab, and ACE-031 aim to block. It is listed here for educational context.

Half-life

Not characterized for exogenous administration; endogenous myostatin circulates in latent complexes

Dosage range

In vitro research: 2-100 ng/mL in cell culture assays. No human therapeutic dosing exists.

Administration

Subcutaneous injection

Research level

Strong

How Myostatin works

Active myostatin binds ActRIIB/ActRIIA receptors, recruiting ALK-4/ALK-5 to trigger Smad2/3 phosphorylation and nuclear translocation. This suppresses MyoD/myogenin, inhibits satellite cell proliferation, upregulates atrogenes (atrogin-1, MuRF-1), and blocks Akt/mTOR protein synthesis. Natural inhibitors include follistatin, FLRG, GASP-1, and decorin.

Also known as: GDF-8, GDF8, Growth Differentiation Factor 8, MSTN

Side effects & safety

Not applicable — research reagent only Elevated myostatin causes muscle atrophy and weakness

Contraindications

Not a therapeutic agent
Administering exogenous myostatin to humans would cause muscle wasting

Consult a healthcare provider before use if any of these apply to you.

FAQ

What is Myostatin? +
The body's primary negative regulator of skeletal muscle mass — a TGF-β superfamily member encoded by the MSTN gene. Its amino acid sequence is 100% conserved across humans, mice, rats, chickens, and pigs. This is a research reagent, not a therapeutic; myostatin inhibitors (follistatin, trevogrumab) are the therapeutic approach. Its mechanism of action is supported by robust clinical evidence.
What is Myostatin researched for? +
Myostatin has the strongest research relevance for . Evidence is supported by robust clinical evidence.
What are the side effects of Myostatin? +
Reported side effects include Not applicable — research reagent only, Elevated myostatin causes muscle atrophy and weakness. Key contraindications: Not a therapeutic agent; Administering exogenous myostatin to humans would cause muscle wasting.
Is Myostatin FDA approved? +
Myostatin is not FDA-approved. It is available as a research compound or through compounding pharmacies in some jurisdictions.
How is Myostatin administered? +
Myostatin is typically administered via subcutaneous route. Researched dosage range: In vitro research: 2-100 ng/mL in cell culture assays. No human therapeutic dosing exists.. Half-life: Not characterized for exogenous administration; endogenous myostatin circulates in latent complexes.

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