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ToolsCompareFollistatin 315 vs Bronchogen

Follistatin 315 vs Bronchogen

Side-by-side comparison of key properties, dosing, and research.

Anabolic & IGF
Follistatin 315
Anti-Aging & Longevity
Bronchogen
Summary
Follistatin 315 is a splice variant isoform of follistatin produced by alternative mRNA processing. Unlike Follistatin 344 which is tethered to cell surfaces via heparan sulfate proteoglycans, FST-315 circulates freely in the bloodstream and has broader systemic distribution. It is the predominant circulating form and exerts systemic myostatin inhibition as well as FSH suppression, making it relevant to both muscle growth and reproductive endocrinology.
Bronchogen is a tetrapeptide bioregulator (Ala-Glu-Asp-Leu) developed by Professor Vladimir Khavinson at the St. Petersburg Institute of Bioregulation and Gerontology. It is a tissue-specific bioregulator designed for the bronchi and lungs, promoting normalization of bronchial epithelial cell function. Research suggests benefits for respiratory health, protection against pulmonary aging, and support for bronchopulmonary conditions.
Half-Life
~3–5 hours (longer systemic circulation vs FST-344)
Short (minutes to hours); bioregulator effects are gene-mediated and longer lasting
Admin Route
SubQ, IM
SubQ, Oral
Research
Typical Dose
No established human dosing protocol
10 mg per day
Frequency
Research use only
Daily for 10–30 days
Key Benefits
  • Systemic myostatin inhibition for whole-body muscle growth
  • Freely circulating — broader tissue distribution than FST-344
  • Strong FSH-suppressive activity useful in certain hormonal protocols
  • Potential for greater anabolic effect across multiple muscle groups simultaneously
  • May be more relevant to reproductive endocrinology applications
  • Studied in gene therapy approaches for muscular dystrophy
  • Tissue-specific support for bronchial and lung health
  • Promotes normalization of bronchial epithelial cell function
  • Potential benefits in chronic bronchitis and COPD support
  • Anti-aging effects on pulmonary tissue
  • May reduce frequency of respiratory infections
  • Supports lung function preservation with aging
  • Compatible with other Khavinson bioregulator peptides
Side Effects
  • Systemic FSH suppression — significant concern for fertility
  • Greater potential for off-target effects vs FST-344 due to systemic distribution
  • Limited human safety data
  • Potential cardiac hypertrophy with prolonged high-dose exposure
  • Generally well tolerated in research studies
  • Mild local reactions at injection site (if injected)
  • No significant systemic side effects reported at standard doses
Stacks With