GHK-Cu (Glycyl-L-Histidyl-L-Lysine copper complex, CAS 49557-75-7) is a naturally occurring tripeptide first isolated from human plasma by Loren Pickart in 1973. With over four decades of peer-reviewed publication, it is among the most extensively characterised peptide compounds in biochemical research literature — studied in extracellular matrix gene expression models, fibroblast culture assays, antioxidant enzyme pathway studies, and preclinical wound models. Supplied exclusively as a laboratory research compound for in vitro use.
GHK-Cu functions through multiple interconnected pathways. Most characterised are its effects on fibroblast activity: GHK-Cu stimulates synthesis of collagen (types I, III, IV, VII), elastin, proteoglycans, glycosaminoglycans (dermatan sulphate, chondroitin sulphate), and the proteoglycan decorin — the structural matrix components that define skin architecture and tissue integrity.
Gene profiling studies using the Broad Institute's Connectivity Map revealed that GHK modulates a remarkably broad gene set — stimulating 47 DNA repair genes (≥50% expression increase), upregulating antioxidant enzyme genes, and influencing pathways related to blood vessel development, nerve outgrowth, and NFκB suppression. This transcriptomic breadth may explain how a single tripeptide can exert diverse biological effects across different tissue types.
GHK-Cu also acts as a chemoattractant, drawing immune cells and endothelial cells to injury sites — accelerating inflammatory resolution and triggering vascular recruitment for repair. In irradiated fibroblast studies, GHK-Cu restored replicative vitality and growth factor production (bFGF, VEGF) in cells where radiation had impaired normal function.
In a randomised double-blind study using nano-lipid carrier encapsulation, topically-applied GHK-Cu demonstrated statistically significant differences versus control in quantitative wrinkle measurement parameters over 8 weeks. A 1999 study by Abdulghani et al. reported differences in collagen mRNA expression versus comparator compounds in a controlled research setting.
Published placebo-controlled studies have reported differences in dermal thickness, extracellular matrix composition, and skin hydration markers as assessed by biopsy immunohistochemistry. All data is from controlled research contexts; these findings do not constitute approval for therapeutic or cosmetic use.
Animal model studies have reported differences in wound closure rate, granulation tissue formation, antioxidant enzyme expression levels, and TNF-β concentrations in GHK-Cu-treated groups versus controls. In rodent diabetic and ischaemic wound models, differences in MMP-2, MMP-9, and TNF-β expression were recorded. All data is preclinical in origin.
Published studies in wound model contexts have reported differences in re-epithelialisation markers. A 1993 rat implant model measured extracellular matrix accumulation (total protein and collagen expression) in treated groups. These are preclinical research findings only and do not constitute approval for therapeutic application.