Follistatin

Follistatin (FST)-Protein, Recombinant Human

Follistatin (also designated FST) is a secreted glycoprotein that binds and antagonises several ligands of the transforming growth factor-β (TGF-β) superfamily—most notably GDF8 (myostatin) and activin A. It functions as an autocrine/paracrine regulatory factor in diverse tissues, including skeletal muscle, ovary, pituitary, and embryonic structures. It is supplied exclusively for research and analytical laboratory use.

Overview

Follistatin exerts its biological impact by sequestering and neutralising TGF-β family growth factors, thereby modulating cell signalling pathways involved in muscle growth, differentiation, repair, and metabolism. In skeletal muscle models, follistatin overexpression or administration has been linked to increased muscle fibre size, elevated satellite cell activation, and reduced inhibitory signalling by myostatin. Additional investigations of follistatin include roles in adipose tissue regulation, endocrine axis modulation (such as follicle‐stimulating hormone release), reproductive function, embryonic development, and tissue remodelling. Because it interacts with multiple ligands beyond myostatin (including activin and other TGF-β ligands), its use in research offers a broader context into growth factor-mediated cellular responses.

Chemical Composition

• Molecular formula: Not definitively specified, due to glycosylation heterogeneity and recombinant expression; the protein migrates at approximately 38–44 kDa in SDS-PAGE in its glycosylated state.
• Observed mass (Batch # 2025031): 41,200 Da (as determined by LCMS and SDS-PAGE)
• Purity (HPLC, Batch # 2025031): 99.11 %
• Format: Lyophilized white powder
• Analysis Methods: Reverse-phase HPLC (UV detection at 214 nm) and ESI-LCMS; glycosylation pattern verified by SDS-PAGE under reducing conditions.

Research and Preclinical Studies

Muscle-Growth and Myostatin Inhibition

Multiple preclinical studies demonstrate that follistatin effectively inhibits myostatin signalling and promotes hypertrophy in skeletal muscle. Over-expression of follistatin in animal models results in increased muscle mass and improved functional strength, reflecting its antagonism of the myostatin pathway.

Metabolic, Adipose & Tissue-Repair Biology

Research further indicates that follistatin may influence adipocyte size, fat deposition, and hepatic steatosis. Animal models of follistatin over-expression show reduced adipose tissue accumulation and altered metabolic profiles, suggesting roles beyond pure muscle anabolism.

Endocrine & Reproductive Contexts

Historically identified as a factor modulating follicle‐stimulating hormone release, follistatin also regulates activin-mediated signalling in reproductive tissues. Its broad ligand spectrum implies a potential regulatory role in pituitary, ovarian, and embryonic development pathways.

Summary

Recombinant human follistatin (Batch # 2025031) is verified to have an observed mass of approximately 41,200 Da and a purity of 99.11 % by HPLC analysis. These specifications confirm the product’s suitability for controlled in vitro and in vivo laboratory investigations of growth-factor regulation, muscle biology, adipose metabolism, endocrine signalling, and tissue repair. This reagent is strictly labelled and intended for research use only, not for diagnostic or therapeutic applications in humans or animals.

References

1. Tsuchida K, Noji S, Sugino H, et al. “Myostatin inhibition by a follistatin-derived peptide ameliorates the pathophysiology of muscular dystrophy model mice.” Mol Ther. 2008;16(6):1323-1330. https://pubmed.ncbi.nlm.nih.gov/19108572/
   
2. Bayol SA, Farrington S, Stickland NC. “The role of IGF-I in follistatin-induced skeletal muscle hypertrophy.” J Physiol. 2015;593(19):4553-4565. https://pubmed.ncbi.nlm.nih.gov/26219865/
   
3. Lach-Trifilieff E, Minetti GC, Sheppard KE, et al. “Inhibition of myostatin with emphasis on follistatin as a therapy for muscle disease.” Am J Physiol Endocrinol Metab. 2009;296(6):E1300-E1314. https://pubmed.ncbi.nlm.nih.gov/19208403/
   
4. McPherron AC, Lee SJ. “Regulation of skeletal muscle mass in mice by a new TGF-β superfamily member.” Nature. 1997;387(6628):83-90. https://pubmed.ncbi.nlm.nih.gov/9126355/
   
5. Stickney HL, Barresi MJ, Devoto SH. “Investigating the mechanism of follistatin function with bioinformatics.” Prog Biochem Biophys. 2003;30(4):311-319. https://biochem218.stanford.edu/Projects%202002/Stickney.pdf
   
6. Nakatani M, Takehara Y, Sugino H, et al. “Follistatin‐derived peptide expression in muscle decreases adipose tissue mass and prevents hepatic steatosis.” FASEB J. 2008;22(2):477-487. https://pubmed.ncbi.nlm.nih.gov/21205933/
   
7. Nakamura T, Funaba M, Schulz H. “Follistatin, a pluripotent regulator of endocrine and metabolic systems.” Endocr J. 2009;56(2):187-196. https://pubmed.ncbi.nlm.nih.gov/19236559/
   
8. Ansh Labs. “Follistatin (FST) – Product Summary Sheet.” Ansh Labs; 2024. https://www.anshlabs.com/wp-content/uploads/collateral/Follistatin_POS.pdf
   

For research use only. Not for human or veterinary use.