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ToolsCompareTestagen vs SLU-PP-332

Testagen vs SLU-PP-332

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

Anti-Aging & Longevity
Testagen
Recovery & RepairFat Loss & Metabolic
SLU-PP-332
Summary
Testagen is a tetrapeptide bioregulator (Lys-Glu-Asp-Gly) developed by Professor Vladimir Khavinson, tissue-specific for the testes. It supports Leydig cell function, normalization of testosterone biosynthesis, and spermatogenic activity. Testagen is used in men's health protocols for age-related testosterone decline, male fertility support, and testicular anti-aging.
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
Short (minutes); sustained gene-regulatory effects
Not established in humans; rodent pharmacokinetics suggest hours
Admin Route
SubQ, Oral
Oral (research), Subcutaneous (research)
Research
Typical Dose
10 mg per day
Not established for humans; rodent studies used ~100 mg/kg/day
Frequency
Daily for 10–30 days
Once daily in rodent studies
Key Benefits
  • Supports endogenous testosterone synthesis via Leydig cell normalization
  • Promotes spermatogenesis and sperm quality
  • Anti-aging effects on testicular tissue
  • May attenuate age-related testosterone decline
  • Mechanistically distinct from TRT — does not suppress HPG axis
  • Useful adjunct to Gonadorelin and Kisspeptin-10 in male hormonal protocols
  • Supports male fertility without exogenous hormone replacement
  • 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
  • Generally well tolerated
  • Mild injection site reactions
  • No significant endocrine disruption reported at standard doses
  • 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