The glycyl l histidyl l lysine Cu2+ tripeptide complex attenuates lung inflammation and fibrosis in silicosis by targeting peroxiredoxin 6 ScienceDirect GHK Cu: The Peptide That Transforms Skin and Tissue Health Calibrate Hydration Why Collagen Loss Accelerates After 40: The Role of GHK Cu in Menopaus Pure & Cimple Defy GHK Cu (glycyl L histidyl L lysine) is a naturally occurring copper binding peptide found in human plasma. As levels decline with age, so may its support of the biological processes involved in collagen production, skin