GHK Cu: The Copper Peptide And The Claims Around It GHK Cu is a naturally occurring copper binding tripeptide found in human plasma. Mechanistically, it's linked to tissue repair signaling, immune modulation, glycosaminoglycan and collagen Quantitation of Copper Tripeptide in Cosmetics via Fabric Phase Sorptive Extraction Combined with Zwitterionic Hydrophilic Interaction Liquid Chromatography and UV Vis Detection JCI Disruption of CSF 1 receptormediated metal ion homeostasis in the murine brain promotes neurodegenerative disease Cholinergic Control of GnRH Neuron Physiology and Luteinizing Hormone Secretion in Male Mice: Involvement of ACh GABA Cotransmission Journal of Neuroscience