GHK-Cu is the copper(II) complex of the naturally occurring tripeptide glycyl-L-histidyl-L-lysine (GHK). Researchers report it was first isolated in 1973 by Loren Pickart as an activity in human albumin, and that GHK circulates in plasma at roughly 200 ng/mL around age 20, declining to about 80 ng/mL by age 60.1 It is supplied for laboratory and cosmetic-ingredient research only. This material is offered strictly for research use; it is not an approved drug and is not intended to diagnose, treat, cure, or prevent any condition. Most published human data come from topical cosmetic formulations rather than injectable use, and much of the mechanistic work is from cell-culture and animal models.12
Sequence & identity
Gly-His-Lys · copper(II) complex C₁₄H₂₃CuN₆O₄⁺ · 402.92 g/mol (free peptide GHK: C₁₄H₂₄N₆O₄, 340.38 g/mol)
Structure of the GHK-Cu copper(II) tripeptide complex. Chemical identity confirmed against PubChem CID 71587328 (InChIKey NZWIFMYRRCMYMN-ACMTZBLWSA-M).3
Mechanisms studied
Researchers report that GHK binds copper(II) with high affinity and delivers it into cells in a redox-silenced, non-toxic form, supplying copper as a cofactor relevant to connective-tissue enzymes involved in skin remodeling.1 In cell and tissue models, investigators observed that GHK stimulates synthesis of collagen, dermatan sulfate, chondroitin sulfate, and the proteoglycan decorin, while modulating matrix metalloproteinases together with their inhibitors TIMP-1 and TIMP-2.1 A gene-expression analysis reported that GHK can up- and down-regulate on the order of 4,000 human genes, with researchers describing associated antioxidant and anti-inflammatory signatures.1 In a fibroblast study, GHK-Cu increased MMP1 and MMP2 expression at the lowest tested concentration while increasing TIMP1 expression across all concentrations.2
Dosing in the research literature
The figures below summarise regimens as reported in published research — they are not recommendations or directions for use.
| Source / model | Regimen reported | Notes |
|---|---|---|
| Badenhorst et al. 2016, J Aging Sci (in-vivo topical) 2 | Topical GHK-Cu encapsulated in a lipid nano-carrier, applied twice daily to facial skin for the in-vivo arm of the study. | As reported in this cosmetic study; not a directive for use. Concentration in the marketed comparator products was not standardized across arms. No established injectable or systemic dosing exists in the published human literature. |
| Pickart & Margolina 2015 review (topical cosmetic trials) 1 | Across cited cosmetic trials, GHK-Cu was formulated into face/eye/thigh creams and applied topically over ~12 weeks. | Reported within cosmetic formulation studies summarized in the review. Exact per-application amounts and vehicle differ by product and are not consistently reported. Provided for research context only, not as usage directions. |
Effects observed in research
In topical cosmetic trials summarized by Pickart and Margolina, investigators reported that GHK-Cu creams improved skin laxity, clarity, firmness, and density and reduced fine lines and wrinkle depth; one 12-week study in 71 women with photoaged skin reported increased skin density and thickness, and a separate 12-week eye-area study in 41 women reported that GHK-Cu outperformed placebo and a vitamin-K control.1 In a thigh-skin comparison the review reported collagen-synthesis increases in 70% of women treated with GHK-Cu versus 50% for a vitamin C cream and 40% for retinoic acid.1 In the Badenhorst study, researchers observed that a GHK-Cu nano-carrier serum reduced facial wrinkle volume by 55.8% (p<0.001) and wrinkle depth by 32.8% (p=0.012) versus a control serum, and reduced wrinkle volume by 31.6% (p=0.004) versus a Matrixyl 3000 comparator.2 These are study-reported observations in research and cosmetic settings and are not claims of medical benefit.
Strength of evidence
Evidence is graded B. Human data exist but are limited to relatively small topical cosmetic trials (tens of participants each), several of which are summarized within author reviews rather than reported as large independent randomized controlled trials.12 The mechanistic and gene-expression work is substantial but largely in-vitro and animal-based, and some originates from researchers commercially associated with the peptide, which warrants cautious interpretation.1 There is little controlled human evidence for injectable or systemic use; published outcomes are predominantly topical. Reported figures for the copper complex (CAS 49557-75-7) and the free peptide were cross-checked against PubChem.3 Where values could not be independently confirmed, they are described as reported by the cited authors rather than presented as established fact.
Reconstitution & storage
Reconstitute with bacteriostatic water for laboratory handling. Store lyophilised material frozen and reconstituted material refrigerated. Use Peptigo’s reconstitution calculator and storage cheat sheet for working figures.
References
- Pickart L, Margolina A. GHK Peptide as a Natural Modulator of Multiple Cellular Pathways in Skin Regeneration. BioMed Research International. 2015;2015:648108. doi:10.1155/2015/648108. PMID: 26236730. https://pmc.ncbi.nlm.nih.gov/articles/PMC4508379/
- Badenhorst T, Svirskis D, Merrilees M, Bolke L, Wu Z. Effects of GHK-Cu on MMP and TIMP Expression, Collagen and Elastin Production, and Facial Wrinkle Parameters. Journal of Aging Science. 2016;4(2):166. doi:10.4172/2329-8847.1000166. https://www.walshmedicalmedia.com/open-access/effects-of-ghkcu-on-mmp-and-timp-expression-collagen-and-elastin-production-and-facial-wrinkle-parameters-2329-8847-1000166.pdf
- National Center for Biotechnology Information. PubChem Compound Summary for CID 71587328 (GHK-Cu, copper tripeptide-1) and CID 73587 (free peptide GHK). https://pubchem.ncbi.nlm.nih.gov/compound/71587328