GHK Cu is a naturally occurring tripeptide in human plasma. Levels average 200 ng ml at age 20 and drop to 80 ng ml by age 60 (Pickart et al., 2020). That decline tracks with Noninvasive and Efficient Peptide Delivery by a Novel Biocompatible Ionic Liquid ACS Sustainable Chemistry & Engineering How GHK Peptide Works Signaling GHK acts as a switch for skin repair: Interacts with adenosine receptors reduces inflammation Activates MAPK ERK, PI3K Akt, TGF pathways Stimulates fibroblasts & keratinocytes boosts collagen, elastin GHK Cu vs AHK Cu: Which Copper Peptide Is More Effective? Frontiers Exploring the beneficial effects of GHK Cu on an experimental model of colitis and the underlying mechanisms