PeptideHormone

Activin A

A TGF-β-family signal sharing myostatin's receptors, with broader roles.

EndogenousEstablished

Identity

Class
TGF-β superfamily dimer (βA–βA)
Source
Many tissues (gonads, muscle, immune cells)
Receptor
Activin type II receptors (ActRIIA/B) → Smad2/3

Mechanism

Activin A signals through the same activin type II receptors as myostatin, contributing to muscle wasting, fibrosis, inflammation, and reproductive signaling depending on context. Its overlap with myostatin is why receptor-level blockade affects both.

Reference notes

  • Activin A and myostatin converge on the same activin type II receptors.
  • It has wide-ranging roles beyond muscle, including in reproduction and fibrosis.
  • Receptor-level (ActRII) blockade affects activin and myostatin together.

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. 1.Principles of the activin receptor signaling pathway and its inhibition · Cytokine & growth factor reviews, 2021 · PMID 33933900
  2. 2.Myostatin/Activin Receptor Ligands in Muscle and the Development Status of Attenuating Drugs · Endocrine reviews, 2022 · PMID 34520530