Middle aged mice treated with GHK Cu peptide administered intraperitoneally or intranasally show behavioral rescue but divergent hippocampal aging programs bioRxiv GHK Cu Peptide Therapy: The Definitive Clinical Guide to Gene Modulation, Protocols, and Efficacy GHK Cu is a powerful copper peptide that supports collagen production, skin and hair health, and tissue repair. It may help reduce fine lines, improve elasticity, and promote faster healing. Want to learn By age 30, your skin produces about 25% less collagen. By 40, that number can reach 40%. This decline affects more than just how your skin looks. It changes how it heals, GHK Cu Peptide Therapy: The Definitive Clinical Guide to Gene Modulation, Protocols, and Efficacy By age 30, your skin produces about 25% less collagen. By 40, that number can reach 40%. This decline affects more than just how your skin looks. It changes how it heals,