The Effect of the Human Peptide GHK on Gene Expression Relevant to Nervous System Function and Cognitive Decline GHK Cu Peptide: Turn Back the Clock Naturally Calibrate Hydration Uses and Benefits #ghk GHK Cu is a naturally occurring peptide in human plasma that declines with age. When used in injections (usually subcutaneous), it can offer various benefits: Skin Rejuvenation and Anti Aging: GHK Cu Copper Peptide: Dosage, Before and After Results, and How It Works Perfect B Frontiers Exploring the beneficial effects of GHK Cu on an experimental model of colitis and the underlying mechanisms Effects of Copper Tripeptide on the Growth and Expression of Growth Factors by Normal and Irradiated Fibroblasts Jeffrey D. Pollard, Susan Quan, Thomas Kang, R. James Koch, 2005