GHK Cu is getting a lot of attention right now, and for good reason. This is not just a skin peptide. It's a copper binding tripeptide with documented effects on gene expression, collagen synthesis, GHK Cu vs NAD+: Which Longevity Peptide Should You Take or Stack? GHK Cu Copper Peptide: Dosage, Before and After Results, and How It Works Perfect B The Effect of the Human Peptide GHK on Gene Expression Relevant to Nervous System Function and Cognitive Decline