The Effect of the Human Peptide GHK on Gene Expression Relevant to Nervous System Function and Cognitive Decline GHK Cu is not Botox. It does not freeze a single muscle. It works because it works at the matrix level. GHK Cu stimulates collagen and glycosaminoglycan synthesis, modulates the matrix metalloproteinases that govern Molecular crystal structure of the tripeptide GHK Cu. In solution, Download Scientific Diagram GHK Cu Peptide: Turn Back the Clock Naturally Calibrate Hydration