GHK-Cu modulates roughly 31% of human genes and drives collagen synthesis at picomolar doses.

What the GHK-Cu record establishes

GHK-Cu is the copper(II) complex of glycyl-L-histidyl-L-lysine, a tripeptide first isolated from human plasma in 1973. Molecular weight: 402.92 Da. CAS: 89030-95-5. INCI name: Copper Tripeptide-1. It is a research peptide and a cosmetic ingredient, not an approved drug by any route.

The signal is the data. In human fibroblast cultures, GHK-Cu raised collagen synthesis dose-dependently — onset between 10⁻¹² and 10⁻¹¹ M, peak near 10⁻⁹ M — without changing cell number, which marks the effect as a specific metabolic shift rather than a growth artifact ^[1]. A Connectivity Map analysis reports that GHK alters expression of about 31.2% of human genes at a 50%-or-greater change threshold: 59% up, 41% down, with strong upregulation of ubiquitin-proteasome, DNA-repair and antioxidant gene sets ^[2]. The widely repeated "~4,000 genes" figure is an extrapolation; the verified threshold table reports on the order of 2,100 genes ^[2].

The sequence is not foreign to the body. GHK occurs within the alpha-2(I) chain of type I collagen and in SPARC/osteonectin, and circulates in plasma, saliva and urine. Plasma levels decline from about 200 ng/mL at age 20 to about 80 ng/mL by age 60, paralleling reduced tissue-repair capacity ^[3]. That decline is what frames GHK research as restorative — replacing a signal the body loses with age — rather than introducing something new. Read the full GHK-Cu research summary for the study-by-study breakdown.

The evidence base has a clear shape. The strongest controlled human data are topical and dermatologic — small placebo-controlled skin trials and one 6-month hair-loss trial of a combination formulation. The broader systemic and gene-level claims rest largely on in-vitro and rodent work, and a substantial share of the foundational literature comes from one investigator group ^[2][7]. This digest leads with what each study measured and is explicit about which tier of evidence it sits in.

This is the canonical compound name and the term this digest uses throughout: GHK-Cu. Where the literature reports skin, hair, wound and gene data on the free peptide GHK rather than the copper chelate, the distinction is flagged — it matters, because copper coordination is required for most of the documented matrix activity ^[1].

GHK Copper Peptide: The Research Picture

The GHK copper peptide is the most-studied member of the copper-peptide class. Its defining feature is copper coordination: the Cu(II) ion binds through the histidine imidazole nitrogen, the glycine alpha-amino nitrogen and the deprotonated glycine-histidine amide nitrogen, leaving the lysine side chain free. The complex has a very high copper stability constant (log K approximately 16.4), far higher than free GHK, which limits pro-oxidant free-copper release ^[6].

That chelation is functional, not incidental. Copper coordination enables lysyl-oxidase-mediated collagen and elastin cross-linking and superoxide-dismutase-like antioxidant chemistry, and it is required for most documented matrix-remodeling activity — the free peptide does not reproduce MMP-2 stimulation in fibroblast cultures ^[1][6]. Across study models the GHK copper peptide stimulates synthesis of collagen, dermatan sulfate, chondroitin sulfate and the proteoglycan decorin ^[3].

What Is a Copper Peptide?

A copper peptide is a short amino-acid chain bound to a copper(II) ion. GHK-Cu — three amino acids, one copper atom — is the archetype. The peptide acts as a carrier and a signal: it delivers copper to enzymes that need it and, in study models, instructs dermal fibroblasts to rebuild the extracellular matrix ^[6].

What Is a Copper Peptide?

A copper peptide is a peptide chelated to copper(II), used as a copper chaperone and signaling molecule. GHK-Cu is the best-characterized example: glycyl-histidyl-lysine bound 1:1 to Cu(II), molecular weight 402.92 Da ^[6]. In research it stimulates fibroblast collagen, elastin and glycosaminoglycan synthesis and modulates matrix-remodeling enzymes ^[1][3].

How Does a Copper Peptide Work?

A copper peptide works by delivering copper to copper-dependent enzymes and by signaling fibroblasts directly. GHK-Cu enables lysyl-oxidase cross-linking and superoxide-dismutase-like antioxidant activity, and at picomolar-to-nanomolar concentrations stimulates collagen synthesis without changing cell number ^[1][6]. Gene-expression analysis reports modulation of roughly 31% of human genes toward repair programs ^[2].

What Is Copper Tripeptide-1 (GHK-Cu)?

Copper Tripeptide-1 is the INCI cosmetic-ingredient name for GHK-Cu — the same molecule, labeled for skincare. On a product ingredient list, "Copper Tripeptide-1" means glycyl-histidyl-lysine copper(II) complex, CAS 89030-95-5.

What Is GHK Copper Peptide?

GHK copper peptide is glycyl-L-histidyl-L-lysine bound to copper(II) — molecular weight 402.92 Da, naturally present in human plasma, saliva and urine ^[6]. In research models it stimulates fibroblast synthesis of collagen, elastin and glycosaminoglycans and modulates the matrix-remodeling enzyme system ^[1][3].

Copper Peptide Serums in the Research Literature

Copper peptide serums and copper tripeptide-1 serums deliver GHK-Cu topically, where a human skin-penetration study measured a permeability coefficient of 2.43 ± 0.51 × 10⁻⁴ cm/h, with about 97 ± 6.6 µg/cm² of copper retained as a dermal depot over 48 hours ^[5]. Native GHK-Cu penetrates poorly (free GHK clogP −2.24), so liposomal and other delivery systems are active areas of formulation research ^[6][13]. This digest summarizes that research; it does not sell or rank products.

What does a GHK-Cu peptide do?

What does a GHK-Cu peptide do?

A GHK-Cu peptide acts as a copper-binding signaling tripeptide. In research models it stimulates dermal fibroblast synthesis of collagen, elastin and glycosaminoglycans while modulating matrix-remodeling enzymes and their inhibitors ^[1][6]. It also functions as a copper chaperone, supplying the metal to copper-dependent enzymes such as lysyl oxidase ^[6].

How does GHK-Cu work?

GHK-Cu works on two levels: as a copper chaperone enabling lysyl-oxidase cross-linking and antioxidant chemistry, and as a pleiotropic signal shifting gene expression toward tissue-repair, DNA-repair and antioxidant programs ^[2][6]. Copper coordination is required — the free peptide does not reproduce key matrix effects ^[1]. See the GHK-Cu dosage in the literature for the concentrations used.

What is the difference between GHK and GHK-Cu?

GHK is the free tripeptide (MW 340.38 Da); GHK-Cu is its copper(II) chelate (MW 402.92 Da) ^[6]. Copper coordination is required for most documented matrix-remodeling activity — the free peptide does not reproduce MMP-2 stimulation in fibroblasts ^[1]. Several studies use free GHK and report systemic or gene-level effects, so the form a study used matters when reading its claims ^[2][8].