Copper tripeptide (GHK-Cu) is a tripeptide. During wound healing, copper tripeptide may be freed from existing extracellular proteins via proteolysis and serves as a chemoattractant for inflammatory and endothelial cells. Copper tripeptide has been shown to increase messenger RNA production for collagen, elastin, proteoglycans, and glycosaminoglycans in fibroblasts. Copper tripeptide is a natural modulator of multiple cllular pathways in skin regeneration.