GHK

Overview

GHK (Glycyl-L-Histidyl-L-Lysine) is a naturally occurring human tripeptide first isolated from human plasma in 1973 by Dr. Loren Pickart. It is the base peptide that forms GHK-Cu when complexed with copper ions. GHK alone has significant biological activity — it can reset gene expression of multiple genes to a healthier state.

A landmark 2012 study by Pickart and colleagues found that GHK could reset the expression of 4,000+ genes in human fibroblasts toward patterns associated with younger, healthier tissue. This gene-resetting ability distinguishes it from most other peptides that target single pathways. GHK levels in human plasma decline from ~200 ng/mL at age 20 to ~80 ng/mL by age 60.

Mechanism of Action

GHK modulates gene expression through multiple mechanisms: it activates or suppresses genes involved in collagen synthesis, anti-oxidant defense, DNA repair, apoptosis regulation, and immune modulation. When complexed with copper (as GHK-Cu), it additionally delivers bioavailable copper to tissues for metalloenzyme function. The peptide's ability to simultaneously affect thousands of genes suggests it acts as a master regulatory signal rather than targeting a single pathway.

Key Research Benefits

Clinical Evidence Summary

Not FDA-approved. Available as cosmetic ingredient and research compound. GHK-Cu (copper complex) is the more commonly available form. Extensive published research by Loren Pickart and others.

Key Studies / PubMed References

Side Effects & Safety

Known Interactions

Frequently Asked Questions

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