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ToolsComparePGPIPN vs Follistatin 315

PGPIPN vs Follistatin 315

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

Immune Support
PGPIPN
Anabolic & IGF
Follistatin 315
Summary
PGPIPN is a bioactive hexapeptide (Pro-Gly-Pro-Ile-Pro-Asn) derived from beta-casein during enzymatic digestion. It exhibits anti-inflammatory properties via opioid receptor modulation and cytokine suppression, making it relevant for gut health, systemic inflammation, and as a component of casein-derived functional foods.
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.
Half-Life
Estimated 30-120 minutes (peptide degradation)
~3–5 hours (longer systemic circulation vs FST-344)
Admin Route
Oral, Subcutaneous (research)
SubQ, IM
Research
Typical Dose
200-500 mg per day
No established human dosing protocol
Frequency
Once or twice daily
Research use only
Key Benefits
  • Anti-inflammatory effects via cytokine suppression
  • Gut mucosal protection and intestinal barrier support
  • Opioid receptor modulation for gut motility regulation
  • Potential analgesic activity via central and peripheral opioid pathways
  • Explored for inflammatory bowel conditions and gut dysbiosis
  • Natural origin (food-derived) with favorable safety profile
  • 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
Side Effects
  • Generally very well-tolerated given food-derived origin
  • Theoretical opioid-mediated constipation at high doses
  • Rare milk protein allergy in casein-sensitive individuals
  • 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
Stacks With