GHK-Cu

What Is GHK-Cu?

GHK-Cu is a naturally occurring tripeptide (glycyl-L-histidyl-L-lysine) bound to a copper(II) ion. It circulates in human plasma at roughly 200 ng/mL at age 20 and falls to about 80 ng/mL by age 60, the observation Pickart used in his foundational work to frame it as a signal the body loses with age. It is among the most transcriptionally active peptides characterised: a 2010 Broad Institute Connectivity Map analysis found GHK modulates expression of over 4,000 human genes, shifting the transcriptome of aged or damaged cells toward a younger profile.

The dominant effects are upregulation of collagen I, III, and IV, fibronectin, decorin, and glycosaminoglycan synthesis in dermal fibroblasts; balancing of matrix metalloproteinases (MMPs) against their inhibitors (TIMPs) so collagen turnover is controlled rather than degradative; VEGF-mediated angiogenesis; and activation of TGF-beta superfamily signalling that drives the wound-repair cascade. The copper ion is the functional cargo: GHK acts as a chaperone that delivers copper into cells as a cofactor for lysyl oxidase (collagen and elastin crosslinking) and superoxide dismutase (antioxidant defence). Systemic plasma half-life is short, roughly 25 to 60 minutes, while tissue-level effects on MMP activity and collagen turnover persist 24 to 72 hours and the regenerative cascade unfolds over weeks in the published wound models.