Research Peptide · For laboratory research use only
Also known as Ala-His-Lys copper complex, Copper tripeptide AHK
AHK-Cu is the copper(II) complex of the tripeptide L-alanyl-L-histidyl-L-lysine (Ala-His-Lys). It is a close analogue of GHK-Cu, differing only in the N-terminal residue, alanine in place of glycine; both peptides carry the N-terminal Xxx-His arrangement that forms a well-characterised class of copper(II) binding sites3,4.
Published research specific to AHK-Cu is very limited. The principal study examined human hair follicles in organ culture and cultured dermal papilla cells1. Related work has examined a vitamin C-conjugated AHK peptide, without copper, in a myoblast cell line2, and the copper coordination chemistry of peptides with the same binding motif3,4.
As described in the research literature
As described in the research literature, peptides beginning NH2-Xxx-His, of which GHK is the canonical example, bind Cu(II) through three nitrogens from the peptide (the terminal amine, a deprotonated amide nitrogen and the histidine imidazole), with an external ligand completing the equatorial plane3,4. Structural and redox studies of Cu(II)-GHK found the complex to be inert under moderate redox potentials, with fast copper exchange4. The AHK complex itself has been characterised less extensively.
In the hair follicle study, AHK-Cu was associated with elongation of human hair follicles ex vivo and with proliferation of dermal papilla cells in vitro; in dermal papilla cells it raised the Bcl-2/Bax ratio and reduced cleaved caspase-3 and PARP, while the reduction in annexin V-labelled apoptotic cells did not reach statistical significance1.
What published studies have examined
Human hair follicles maintained ex vivo were examined for elongation, and cultured human dermal papilla cells for proliferation and apoptosis markers, including annexin V and propidium iodide labelling, Bcl-2/Bax ratio and cleaved caspase-3 and PARP1.
Sources [1]
A vitamin C-linker-conjugated AHK peptide was examined in mouse C2C12 myoblasts for proliferation, BMP-2-induced alkaline phosphatase, Smad1/5/8 and MAPK signalling, and osteoblast gene expression2. The conjugate is not a copper complex, so these findings do not transfer directly to AHK-Cu.
Sources [2]
X-ray, EPR, X-ray absorption and NMR studies characterised the Cu(II) complexes of GHK and DAHK and their redox behaviour4. A multispectroscopic study of Ala-His-His examined how the Xxx-His and Xxx-Zzz-His copper binding motifs compete with pH3.
The effect of tripeptide-copper complex on human hair growth in vitro.
Pyo HK, Yoo HG, Won CH, et al. Archives of Pharmacal Research, 2007.
Vitamin C-linker-conjugated tripeptide AHK stimulates BMP-2-induced osteogenic differentiation of mouse myoblast C2C12 cells.
Jung JI, Park KY, Lee Y, et al. Differentiation, 2018.
Cu(II) Binding to the Peptide Ala-His-His, a Chimera of the Canonical Cu(II)-Binding Motifs Xxx-His and Xxx-Zzz-His.
Gonzalez P, Vileno B, Bossak K, et al. Inorganic Chemistry, 2017.
X-ray and solution structures of Cu(II) GHK and Cu(II) DAHK complexes: influence on their redox properties.
Hureau C, Eury H, Guillot R, et al. Chemistry: A European Journal, 2011.
This page is provided for research and educational reference only. It does not constitute medical advice, dosing guidance, or a recommendation for use. All compounds are strictly for laboratory and in-vitro research purposes.