The endogenous antagonist that neutralizes myostatin and activin. Structurally it is Secreted glycoprotein (multiple isoforms).

How strong is the evidence for Follistatin?

PeptideHormone grades Follistatin at the "Established" evidence tier — its mechanism and core effects are settled across the peer-reviewed literature. It is catalogued as an endogenous signal the body produces itself, and the tier is an editorial judgment about the public literature that can change as the science does.

What is the half-life of Follistatin?

The reported circulating half-life of Follistatin is ~minutes (rapid clearance; form-dependent).

Follistatin

The endogenous antagonist that neutralizes myostatin and activin.

EndogenousEstablished

The body's own antagonist to its own brake. Before anyone thought to inhibit myostatin, the physiology had already done it.

Identity

Class: Secreted glycoprotein (multiple isoforms)
Source: Many tissues
Receptor: Ligand trap — binds activin/myostatin, no signaling receptor of its own

Key properties

Evidence floorPreclinicalREF1PRE1

Molecular weight

≈ 35,000 Da

REF

Half-life (native)

~minutes (rapid clearance; form-dependent)

PRE

Approximate values for the native hormone; engineered analogs are often deliberately larger and far longer-acting. Each figure carries its own provenance tier, and the floor is the weakest of them - the Standard.

Mechanism

Follistatin does not signal through a receptor; it binds activin and myostatin directly and neutralizes them. By removing the brake, raising follistatin increases muscle mass — making it a focus of gene-therapy and muscle-disease research.

Reference notes

Follistatin is a ligand trap, not a receptor agonist — it works by sequestering activin and myostatin.
Increasing follistatin raises muscle mass by relieving the myostatin/activin brake.
It is studied in muscular dystrophy and muscle-wasting research.

Common questions

What is Follistatin?: The endogenous antagonist that neutralizes myostatin and activin. Structurally it is Secreted glycoprotein (multiple isoforms).
How does Follistatin work?: Follistatin does not signal through a receptor; it binds activin and myostatin directly and neutralizes them. By removing the brake, raising follistatin increases muscle mass — making it a focus of gene-therapy and muscle-disease research.
How strong is the evidence for Follistatin?: PeptideHormone grades Follistatin at the "Established" evidence tier — its mechanism and core effects are settled across the peer-reviewed literature. It is catalogued as an endogenous signal the body produces itself, and the tier is an editorial judgment about the public literature that can change as the science does.
What is the half-life of Follistatin?: The reported circulating half-life of Follistatin is ~minutes (rapid clearance; form-dependent).

Selected literature

Curated peer-reviewed reviews, sourced from PubMed. Selected for relevance, not exhaustive — open any entry on PubMed for the full record and its primary citations.

1.Follistatin · The international journal of biochemistry & cell biology, 1998 · PMID 9785474
2.Follistatin and follistatin-like 3 in metabolic disorders · Prostaglandins & other lipid mediators, 2023 · PMID 37739334

External references

Follistatin in the public knowledge graph — the same entity resolved across the authoritative chemistry and protein databases.