GHK-Cu
GHK-Cu — Glycyl-L-histidyl-L-lysine copper complex, a naturally occurring tripeptide-copper chelate studied for its role in wound healing and tissue remodeling signaling.
What Is GHK-Cu?
GHK-Cu (copper peptide, glycyl-L-histidyl-L-lysine:copper(II)) is a naturally occurring tripeptide with the amino acid sequence Gly-His-Lys that forms a strong complex with copper(II) ions. It was first identified in human plasma by Dr. Loren Pickart in 1973, where its concentration decreases significantly with age, from approximately 200 ng/mL at age 20 to 80 ng/mL by age 60.
The peptide-copper complex has a molecular weight of 403.93 Da and is one of the smallest bioactive peptide sequences known. Its compact size and metal-chelating properties make it structurally and functionally distinct from most other research peptides.
Mechanism of Action
GHK-Cu functions through multiple mechanisms. The copper ion is essential for activity, as the apo-peptide (GHK without copper) shows significantly reduced biological effects. The complex acts as a bidentate copper transporter, delivering copper to cells where it serves as a cofactor for enzymes including superoxide dismutase (SOD), lysyl oxidase, and cytochrome c oxidase.
Gene expression studies have shown that GHK-Cu can modulate the expression of over 4,000 genes, with significant effects on genes involved in:
- Extracellular matrix remodeling: Upregulation of collagen I, III, and V, elastin, and decorin synthesis
- Antioxidant defense: Induction of superoxide dismutase and other free radical scavengers
- Anti-inflammatory pathways: Suppression of TGF-beta, TNF-alpha, and IL-6 in cell models
- Tissue repair signaling: Activation of stem cell markers and growth factor receptors
Published Research
GHK-Cu has one of the most extensive publication histories of any research peptide, with studies spanning over five decades:
- Wound healing: Controlled studies have demonstrated accelerated wound contraction, increased angiogenesis, and enhanced collagen deposition (Pickart et al., 2012)
- Skin biology: GHK-Cu has shown the ability to stimulate collagen synthesis, improve skin elasticity, and reduce photodamage markers in tissue culture models
- Hair biology: Research has demonstrated enlargement of hair follicle size and stimulation of hair growth in organ culture models
- Bone biology: The peptide has shown osteogenic effects, promoting differentiation of mesenchymal stem cells toward bone-forming osteoblasts
Reconstitution and Stability
GHK-Cu is supplied as a blue-tinged lyophilized powder (the color comes from the copper complex). Reconstitute in sterile water or bacteriostatic water. The solution will appear light blue, confirming the copper complex is intact. Store reconstituted solutions at 2-8°C and protect from light, as copper peptide complexes can be photosensitive.
Unlike many peptides, GHK-Cu is relatively stable in aqueous solution due to the stabilizing effect of the copper coordination. However, exposure to strong reducing agents like DTT will disrupt the copper complex and should be avoided.
Frequently Asked Questions
What is GHK-Cu?
Glycyl-L-histidyl-L-lysine copper complex, a naturally occurring tripeptide-copper chelate studied for its role in wound healing and tissue remodeling signaling.
Why is GHK-Cu important in peptide research?
GHK-Cu is a fundamental concept in compound as it relates to peptide science. It directly influences experimental design, compound characterization, and the reliability of research outcomes across biochemistry and molecular biology disciplines.