Follistatin vs SLU-PP-332
Side-by-side comparison of key properties, dosing, and research.
Anabolic & IGF
FollistatinRecovery & RepairFat Loss & Metabolic
SLU-PP-332- 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.
- SLU-PP-332 is a small molecule exercise mimetic that activates estrogen-related receptors ERRalpha and ERRdelta (ERRa/d), transcription factors that drive oxidative metabolism programs. In animal studies it significantly enhanced endurance capacity and metabolic fitness without exercise, mimicking many of the cardiovascular and metabolic adaptations of aerobic training.
- Half-Life
- ~3–5 hours (endogenous form)
- Not established in humans; rodent pharmacokinetics suggest hours
- Admin Route
- IM, SubQ
- Oral (research), Subcutaneous (research)
- Research
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- Typical Dose
- 50–100 mcg per injection site
- Not established for humans; rodent studies used ~100 mg/kg/day
- Frequency
- Every other day or 2–3x per week
- Once daily in rodent studies
- 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
- Significant enhancement of aerobic endurance capacity
- Increases mitochondrial density and oxidative metabolism in muscle
- Promotes beneficial shift toward oxidative muscle fiber phenotype
- Improves cardiac efficiency and cardiovascular fitness markers
- Potential for obesity, metabolic syndrome, and heart failure treatment
- Exercise mimetic for populations unable to exercise (disability, frailty, disease)
- 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
- Limited human data; all studies are preclinical (rodent)
- Unknown cardiovascular effects with long-term or high-dose use in humans
- Potential hormonal interactions via ERR pathway (ERRs modulate estrogen-related signaling)
- Off-target effects not fully characterized
- Stacks With
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