Exploring Extracellular Matrix Crosslinking as a Therapeutic Approach to Fibrosis GHK Cu: Four Decades of Copper Peptide Science and What Researchers Are Finding Praetorian Peptides Frontiers Molecular Insights Into Lysyl Oxidases in Cartilage Regeneration and Rejuvenation Introduction GHK Cu is a copper peptide complex formed from the tripeptide glycyl L histidyl L lysine bound to copper. This compound has garnered significant attention in both laboratory and formulation research due to its critical role