FST-344 (Follistatin 344)

FST-344 from Super Human Peptides UK is a synthetic, recombinant version of the naturally occurring Follistatin glycoprotein. In humans and animals, follistatin acts as a highly potent autocrine glycoprotein that binds to and neutralizes ligands of the TGF-beta family. In laboratory research, FST-344 is revered as the ultimate model for investigating myostatin blockade.

Myostatin (GDF-8) is the primary regulatory protein that actively limits and halts muscle growth. Researchers utilize FST-344 because it binds directly to myostatin and activin, completely neutralizing their muscle-wasting signals. By removing the biological "brakes" on muscle growth, FST-344 triggers profound cellular hypertrophy and hyperplasia.

Produced under GMP-compliant conditions and verified for 99% purity or higher, FST-344 is an essential tool for advanced research into muscular dystrophy, cachexia, and extreme musculoskeletal regeneration.

• —Myostatin Inhibitor: Binds to and neutralizes Growth Differentiation Factor 8 (GDF-8).
• —Activin Binding: Suppresses activin, further reducing muscle catabolism and fibrosis.
• —Muscle Hyperplasia & Hypertrophy: Studied for its ability to induce massive increases in both muscle cell size and number.
• —High Purity: 99% purity or higher (verified by HPLC and MS analysis).
• —Quality Standard: GMP / ISO certified manufacturing.
• —Documentation: Full Certificate of Analysis (COA) included with every batch.

• —Myostatin Neutralization: Studying the physical binding of Follistatin to GDF-8 to prevent it from activating the ActRIIB receptor on muscle cells.
• —Muscular Dystrophy Models: Preclinical models investigating the rescue of severe muscle wasting in Duchenne and Becker muscular dystrophy.
• —Cachexia Reversal: Researching the prevention of severe lean tissue loss induced by oncology treatments or metabolic disease.
• —Fibrosis Reduction: Evaluating the peptide's ability to inhibit activin-mediated tissue scarring and fibrosis in aged skeletal muscle. Hypertrophy vs.
• —Hyperplasia: Measuring the distinct increases in muscle fiber cross-sectional area alongside the generation of entirely new muscle fibers.

Follistatin was initially discovered in the late 1980s as a reproductive hormone regulator, but its role in muscle biology revolutionized the field of musculoskeletal research. Landmark studies by Se-Jin Lee and others demonstrated that manipulating the myostatin pathway leads to the "double-muscling" phenotype observed in certain animal species (like the Belgian Blue cow). Laboratory studies utilizing FST-344 have consistently shown staggering results.

Because the 344-amino-acid variant of Follistatin circumvents certain tissue-binding limitations of other variants (like FST-315), it allows for profound systemic and localized myostatin inhibition. Animal models administered FST-344 exhibit massive, rapid increases in lean muscle mass and strength, often exceeding the results seen with traditional anabolic agents. Furthermore, research indicates that unlike direct anabolic hormones, FST-344 does not cause organomegaly (enlargement of internal organs) to the same degree, making it a critical focus for safe, targeted muscle-wasting therapies.

• 1.Lee, S.J. et al., "Regulation of muscle growth by multiple ligands signaling through activin type II receptors," Proceedings of the National Academy of Sciences, 2005.
• 2.Haidet, A.M. et al., "Long-term enhancement of skeletal muscle mass and strength by single gene administration of myostatin inhibitors," Proceedings of the National Academy of Sciences, 2008.
• 3.Nakatani, M. et al., "Transgenic expression of a myostatin inhibitor derived from follistatin increases skeletal muscle mass and ameliorates dystrophic pathology in mdx mice," The FASEB Journal, 2008.
• 4.Datta, A. et al., "Follistatin, a mutant myostatin propeptide, and an adeno-associated virus-mediated follistatin gene therapy all improve muscle pathology in mdx mice," Human Gene Therapy, 2009.