GHKCU is one of the most popular peptides out there and for good reason. Results are not instant, as it regenerates the skin form the inside out, and it also will awaken Glutathione Supplements vs. Food Sources: Which is Better? Three amino acids. One copper ion. Decades of research. What makes GHK Cu relevant: 1.Extracellular matrix signaling and collagen pathways 2.Gene expression modulation across tissue models 3.Oxidative stress response mechanisms 4.Cellular repair and NL GHK Cu in the nervous system Synthagen PL