Follistatin vs PE-22-28
Side-by-side comparison of key properties, dosing, and research.
Anabolic & IGF
FollistatinCognitive Enhancement
PE-22-28- Summary
- Follistatin is an endogenous glycoprotein that acts as a potent inhibitor of myostatin and activin, two proteins that limit muscle growth. By binding and neutralizing myostatin, follistatin removes the primary brake on skeletal muscle hypertrophy, enabling significant muscle growth beyond normal physiological limits. It is distinct from its isoforms Follistatin 315 and Follistatin 344 in tissue distribution and binding affinity.
- PE-22-28 is a synthetic analog of spadin derived from sortilin, designed to block TREK-1 potassium channels with rapid-onset antidepressant and neurogenic effects. It shows fast-acting depression relief (within 24 hours) and promotes hippocampal neurogenesis.
- Half-Life
- ~3–5 hours (endogenous form)
- Relatively short; CNS effects may persist due to neurogenic mechanisms
- Admin Route
- IM, SubQ
- SubQ, Intranasal
- Research
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- Typical Dose
- 50–100 mcg per injection site
- 200–400 mcg
- Frequency
- Every other day or 2–3x per week
- Once daily
- Key Benefits
- Potent myostatin inhibition enabling supraphysiological muscle growth
- Increases skeletal muscle mass and fiber size
- May accelerate recovery from muscle injury
- Potential benefits in muscular dystrophy and sarcopenia
- Synergistic with IGF-1 and growth hormone in anabolic protocols
- Animal studies show dramatic increases in muscle mass
- Reduces muscle fibrosis in dystrophic models
- Rapid-onset antidepressant effects (within 24 hours)
- Promotes hippocampal neurogenesis
- Improves cognitive performance and memory
- Reduces anxiety and depressive behavior
- Novel mechanism — does not act on serotonin/dopamine/GABA receptors directly
- May help treatment-resistant depression
- Neuroprotective effects
- Side Effects
- Potential for excessive muscle growth if doses are not controlled
- FSH suppression with implications for fertility in women
- Theoretical risk of cardiac hypertrophy with prolonged high-dose use
- Limited human safety data available
- +1 more
- Generally well tolerated in animal models
- Limited human data available
- Possible mild headache or transient mood changes at initiation
- Injection site reactions (SC)
- Stacks With
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