Definition
The tripeptide glycyl-histidyl-lysine bound to copper(II), isolated from human plasma and studied in tissue remodelling.
GHK-Cu is a complex of the tripeptide glycyl-L-histidyl-L-lysine with a copper(II) ion. Loren Pickart identified GHK in human plasma in 1973, and its high affinity for copper was characterised soon after. Plasma levels have been reported to decline with age. In cell culture and animal models, GHK-Cu has been investigated for effects on collagen and glycosaminoglycan synthesis, wound contraction and gene-expression signatures related to tissue remodelling. It is widely used as an ingredient in cosmetic skin-care products, where it is regulated as a cosmetic rather than a medicine. Controlled clinical evidence beyond cosmetic endpoints is limited.