GHK-Cu and AHK-Cu compared: chemistry, targets and regulatory records
GHK-Cu and AHK-Cu are copper(II) complexes of two tripeptides that differ only at the first residue, glycine in GHK and alanine in AHK. GHK-Cu has a large literature; AHK-Cu has a small one.
Research-use information. This page summarises published literature and regulator records. It is not guidance for use, not medical advice, and not a statement that any material is suitable for use in people or animals.
How do GHK-Cu and AHK-Cu differ on the facts?
| Fact | GHK-Cu | AHK-Cu |
|---|---|---|
| Class | Copper-binding tripeptide complex | Copper-binding tripeptide complex |
| Length | 3 residues | 3 residues |
| Molecular formula | C14H23CuN6O4+ | C15H26N6O4 |
| Average molecular weight | 402.92 g/mol | 354.41 g/mol |
| Receptor or pathway background | Copper-binding tripeptides | Copper-binding tripeptides |
| FDA (Drugs@FDA) | No application listed | No application listed |
| EMA (centrally authorised) | No centrally authorised medicine listed | No centrally authorised medicine listed |
| MHRA (Products) | No product document found | No product document found |
| WADA 2026 list | Not named | Not named |
| Studies in our library | 6 | 2 |
| PubMed records for the search terms | 165 | 31 |
| Registered studies (ClinicalTrials.gov) | 2 | 0 |
Data dates: chemistry checked against PubChem 2026-10-05; regulatory records 2026-10-05; WADA list 2026-10-05; PubMed counts 2026-10-05.
What do the cited papers say differs between GHK-Cu and AHK-Cu?
- The two peptides differ only at residue 1 (Gly-His-Lys against Ala-His-Lys), computed from the catalog sequences.
- GHK's copper(II) complexes have determined X-ray and solution structures and a fibroblast collagen-synthesis study; AHK-Cu has one ex vivo hair-follicle study and a conjugate cell study.[4],[6],[5],[2]
- Reviews of GHK-Cu cover extracellular-matrix turnover and gene expression datasets.[3],[1]
Nothing on this page ranks one compound above the other or states what either does for a person.
Which studies are cited on this page?
[1] Pickart L, Margolina A. Regenerative and Protective Actions of the GHK-Cu Peptide in the Light of the New Gene Data. Int J Mol Sci. 2018;19.
Narrative review of reported GHK-Cu actions on extracellular-matrix, tissue-repair and gene-expression data, including genome-wide expression datasets.
[2] Jung JI, Park KY, Lee Y, Park M, Kim J. Vitamin C-linker-conjugated tripeptide AHK stimulates BMP-2-induced osteogenic differentiation of mouse myoblast C2C12 cells. Differentiation. 2018;101:1-7.
Examined a vitamin C-linked conjugate of the AHK tripeptide (not the copper complex) on osteoblast differentiation in a cell culture model.
[3] Pickart L, Vasquez-Soltero JM, Margolina A. GHK Peptide as a Natural Modulator of Multiple Cellular Pathways in Skin Regeneration. Biomed Res Int. 2015;2015:648108.
Review of GHK in skin biology: collagen and glycosaminoglycan synthesis, metalloproteinase modulation and copper-dependent pathways.
[4] Hureau C, Eury H, Guillot R, Bijani C, Sayen S, Solari PL, et al.. X-ray and solution structures of Cu(II) GHK and Cu(II) DAHK complexes: influence on their redox properties. Chemistry. 2011;17:10151-60.
Solid-state (X-ray) and solution structures of the copper(II) complexes of GHK and DAHK, with spectroscopy of their redox properties.
[5] Pyo HK, Yoo HG, Won CH, Lee SH, Kang YJ, Eun HC, et al.. The effect of tripeptide-copper complex on human hair growth in vitro. Arch Pharm Res. 2007;30:834-9.
Examined AHK-Cu on human hair follicles ex vivo and on cultured dermal papilla cells.
[6] Maquart FX, Pickart L, Laurent M, Gillery P, Monboisse JC, Borel JP. Stimulation of collagen synthesis in fibroblast cultures by the tripeptide-copper complex glycyl-L-histidyl-L-lysine-Cu2+. FEBS Lett. 1988;238:343-6.
Measured collagen synthesis in cultured fibroblasts exposed to the GHK-Cu complex over a range of concentrations.