GHK-Cu

GHK-Cu is a naturally occurring copper-binding tripeptide (Gly-His-Lys complexed with Cu2+) found in human plasma, saliva, and urine. It plays a fundamental role in tissue remodeling by stimulating collagen and elastin synthesis, promoting angiogenesis, recruiting immune cells to wound sites, and modulating inflammatory responses. Plasma levels of GHK-Cu decline significantly with age — from approximately 200 ng/mL at age 20 to 80 ng/mL by age 60 — which correlates with the progressive loss of regenerative capacity observed in aging tissues.

The biological reach of GHK-Cu extends far beyond its initial cosmetic applications. A landmark 2012 study using the Connectivity Map (cMap) database revealed that GHK modulates the expression of over 4,000 human genes, representing roughly 6% of the human genome. Many of these genes are involved in tissue repair, antioxidant defense, stem cell differentiation, and extracellular matrix remodeling. The copper component is essential for full biological activity, serving as a cofactor for enzymes involved in collagen cross-linking (lysyl oxidase) and antioxidant defense (superoxide dismutase).

GHK-Cu is widely used in topical skincare products for anti-aging and wound healing, making it one of the most commercially successful peptides in the cosmetic industry. Subcutaneous injection for systemic effects is also practiced in the wellness community, though this route of administration has less clinical validation. The peptide is active at very low concentrations (nanomolar range), and its naturally occurring status in human physiology contributes to an excellent safety and tolerability profile.

GHK-Cu was first identified in 1973 by Dr. Loren Pickart while studying the differences between old and young human blood at the Biochemistry Department of the University of Washington. He discovered that a factor in young blood plasma promoted the synthesis of fibrinogen by old liver tissue, and this factor was identified as the tripeptide glycyl-L-histidyl-L-lysine complexed with copper (GHK-Cu). Subsequent work throughout the 1980s and 1990s established its roles in wound healing, skin remodeling, and collagen synthesis. The discovery that GHK-Cu modulates the expression of over 4,000 human genes (published in 2012) expanded understanding of its biological significance far beyond its initial cosmetic applications. It is now one of the most commercially successful peptides in the skincare industry.