- Summary
- GHK is the natural tripeptide (Gly-His-Lys) released from human albumin that activates tissue remodeling, collagen synthesis, and anti-aging gene expression. The copper-free form is the biological signaling molecule; it chelates copper in tissue to form GHK-Cu but also has independent biological activity.
- P21 is a synthetic peptide derived from CNTF (ciliary neurotrophic factor) that promotes hippocampal neurogenesis, enhances memory and spatial learning, and may reduce amyloid-beta pathology. It is used as a neurogenic and cognitive enhancer with potential anti-Alzheimer's applications.
- Half-Life
- Extremely short as free peptide; tissue binding extends local effects
- Not well characterized; likely short, but neurogenic effects persist long after administration
- Admin Route
- SubQ, Topical, Oral
- SubQ, Intranasal
- Research
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- Typical Dose
- 100–500 mcg
- 100–500 mcg
- Frequency
- Daily or 5x per week
- Once daily
- Key Benefits
- Stimulates collagen and extracellular matrix synthesis
- Activates tissue repair gene expression programs
- Anti-aging: reverses 57% of age-related gene changes
- Antioxidant and anti-inflammatory
- Wound healing and skin barrier repair
- Improves skin laxity, texture, and radiance
- Neuroprotective (stimulates NGF, BDNF)
- Anti-fibrotic in liver and lung models
- Promotes hippocampal neurogenesis
- Enhances spatial memory and learning
- Increases BDNF expression
- Reduces amyloid-beta plaque formation (animal models)
- Anti-tau pathology potential
- Cognitive enhancement without stimulant effects
- Potential therapeutic for Alzheimer's and cognitive aging
- Side Effects
- Excellent safety profile (naturally occurring peptide)
- Rare: mild injection site reaction (SC)
- No significant adverse effects identified in research
- Generally well tolerated in animal studies
- Limited human clinical data
- Injection site reactions
- Potential mild fatigue at initiation
- Stacks With
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