PE-22-28 vs Testagen
Side-by-side comparison of key properties, dosing, and research.
- Summary
- 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.
- 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.
- Half-Life
- Relatively short; CNS effects may persist due to neurogenic mechanisms
- Short (minutes); sustained gene-regulatory effects
- Admin Route
- SubQ, Intranasal
- SubQ, Oral
- Research
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- Typical Dose
- 200–400 mcg
- 10 mg per day
- Frequency
- Once daily
- Daily for 10–30 days
- Key Benefits
- 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
- 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
- Side Effects
- Generally well tolerated in animal models
- Limited human data available
- Possible mild headache or transient mood changes at initiation
- Injection site reactions (SC)
- Generally well tolerated
- Mild injection site reactions
- No significant endocrine disruption reported at standard doses
- Stacks With
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