Follistatin 344Also known as: FST-344, Follistatin, Follistatin-344

Mechanism of Action

Follistatin 344 is a recombinant peptide that functions by binding to and neutralizing myostatin (GDF-8) and other members of the transforming growth factor-beta (TGF-β) superfamily. Myostatin is a negative regulator of muscle growth, so its inhibition by Follistatin 344 releases the suppression on muscle hypertrophy, leading to increased muscle mass, enhanced regeneration, and recovery of skeletal muscle tissues in preclinical models.

Reported Research Benefits

Primarily utilized in laboratory and preclinical research to investigate muscle hypertrophy, muscle regeneration, mitigation of muscle wasting conditions such as sarcopenia and muscular dystrophies, and therapeutic recovery following muscle trauma or intensive physical stress. It is investigated as an anabolically active agent to improve muscle strength and size.

Dosing Protocol & Reconstitution

Follistatin 344 is supplied as lyophilized powder to be reconstituted with bacteriostatic water before use. Research dosing generally involves subcutaneous injection in animal models with doses tailored per experimental protocol. No standardized human dosing exists since it is exclusively for research purposes.

Research Notes

Preclinical studies show significant muscle mass increases in treated animals through myostatin neutralization. Follistatin 344 displays a role in skeletal muscle regeneration and recovery. Stability is maintained when stored refrigerated (2–8°C) after reconstitution, with a usable life of up to 60 days. Purity is consistently ≥99%, verified by Certificate of Analysis (COA).

Research Summary

Follistatin 344 is a splice variant of follistatin that binds and inhibits myostatin, activin, and other TGF-β superfamily members, removing a key brake on skeletal muscle growth. Gene therapy studies demonstrate dramatic muscle hypertrophy in animal models, and it is being investigated for muscular dystrophy and sarcopenia. The 344 isoform has a heparin-binding domain enabling it to localize to tissues.

Side Effects & Safety

Limited human safety data. Supraphysiological doses may cause organ enlargement beyond skeletal muscle (heart, liver). Potential off-target inhibition of activin signaling affecting reproductive hormones. FSH suppression reported in clinical observations.

Stability & Storage

Refer to research notes

Molecular Data

Sequence: MNRGPLFRVV PQLLTAVRVT SPLHPPGRLL SSPGQVFSWG ESMDGDGSPD HVAFAGVWLK VDTCGPDMSA LASFFLSETE NADTFVVIDA HLFFYVEREV RLALTEESVA QKVWCGKATL ADWVQELVKS HPTPKKCCLL LFSGKESGQG TVQVKWDCVQ NKKNSSSAHN QDGIDMLLKA EQVIPFVPWR HLPALRVADN LCEEKGIKGV RTVVNILSPV YESYLLKGIE ADLCRLKELG GTEVPCVVDL RDRLGALRSN SIRAVLTPGA TPPEDHQDNV PHIFDELKGG K
Molecular Weight: 37646 g/mol

Primary literature: https://pubmed.ncbi.nlm.nih.gov/?term=Follistatin+344+myostatin+muscle+growth