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ToolsCompareTestagen vs PGPIPN

Testagen vs PGPIPN

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

Anti-Aging & Longevity
Testagen
Immune Support
PGPIPN
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.
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.
Half-Life
Short (minutes); sustained gene-regulatory effects
Estimated 30-120 minutes (peptide degradation)
Admin Route
SubQ, Oral
Oral, Subcutaneous (research)
Research
Typical Dose
10 mg per day
200-500 mg per day
Frequency
Daily for 10–30 days
Once or twice daily
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
  • 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
Side Effects
  • Generally well tolerated
  • Mild injection site reactions
  • No significant endocrine disruption reported at standard doses
  • Generally very well-tolerated given food-derived origin
  • Theoretical opioid-mediated constipation at high doses
  • Rare milk protein allergy in casein-sensitive individuals
Stacks With