Young Goose Blue Peptide Spray Your body already knows how to heal. The question is whether the signals are still strong enough. One of the most fascinating peptides studied in regenerative medicine is GHK Cu, a naturally occurring GHK Cu is a copper peptide that plays a role in tissue repair and collagen synthesis. The result: improved texture, firmness, and overall skin quality. GHK Cu may Prevent Oxidative Stress in Skin by Regulating Copper and Modifying Expression of Numerous Antioxidant Genes