Direct Answer
Tripeptide-1 (GHK; glycyl-L-histidyl-L-lysine) is a naturally occurring tripeptide used in cosmetics. Much of the skin literature concerns its copper complex (copper tripeptide-1 / GHK-Cu, summarized separately); cited evidence for the copper-free tripeptide is largely in vitro and review-level.
Summary Table
Evidence Level
High
Key Information
Classification
Key Takeaways
- Tripeptide-1 (GHK) is a naturally occurring tripeptide used in cosmetics
- Most skin-appearance evidence concerns the copper complex GHK-Cu (covered separately)
- Cited copper-free GHK evidence is in vitro and review-level
Scientific Overview
In Plain English
Tripeptide-1, also called GHK, is a small peptide the body produces and that is used in skincare. Most skin research is on its copper-bound form (GHK-Cu); for the copper-free peptide, the cited evidence is mainly laboratory (cell) studies and review summaries.
Scientific Details
Tripeptide-1 (GHK) is a glycyl-histidyl-lysine tripeptide. A review summarizes tissue-remodeling activity and indicates that controlled human skincare findings (skin firmness, elasticity, and fine-line and photodamage appearance) are largely described for the copper complex GHK-Cu. An in vitro study in human dermal fibroblasts reported that GHK and its copper complex reduced IGF-2-dependent TGF-beta1 secretion, relevant to scar-related signaling.
How It Works
GHK is described in research in relation to extracellular-matrix and tissue-remodeling signaling; the cited human skincare appearance findings are largely associated with the copper complex GHK-Cu rather than the copper-free peptide.
Mechanism of Action
Tissue-remodeling signaling
cell
Review and in vitro work describe GHK in relation to extracellular-matrix remodeling; the human appearance findings are largely associated with the copper complex.
Evidence Level
Human Evidence
Human skincare appearance findings in the cited review are largely attributed to the copper complex (GHK-Cu), summarized separately.
Cell Evidence
An in vitro fibroblast study reported reduced TGF-beta1 secretion with GHK and its copper complex.
Limitations
For the copper-free tripeptide specifically, cited evidence is in vitro and review-level; much of the skin-appearance evidence concerns GHK-Cu.
References
- The human tri-peptide GHK and tissue remodeling. Journal of Biomaterials Science, Polymer Edition.Reviewdoi:10.1163/156856208784909435 →
- Effect of GLY-HIS-LYS and its copper complex on TGF-beta secretion in normal human dermal fibroblasts. Acta Poloniae Pharmaceutica.Cell / In VitroPMID: 25745767 →
Alternative Names
- GHK
- Glycyl-L-histidyl-L-lysine
- Gly-His-Lys
Claim Boundaries
ION BLUE is an educational research aggregator. This content summarizes published scientific literature. It is not medically reviewed, is not medical advice, and is not a recommendation to use any substance. Several peptides discussed are research chemicals not approved for human use. Consult a licensed healthcare provider. Much skin-appearance evidence concerns the copper complex (GHK-Cu); this entry is not a recommendation to use the ingredient for any purpose.
This page summarizes published research and is for informational purposes only; it is not medical advice.