GHK-Cu: Copper-Binding Tripeptide in Cellular and Wound Research¶
Executive Summary¶
GHK-Cu (glycyl-L-histidyl-L-lysine-copper(II)) is a naturally occurring tripeptide-copper complex first isolated from human plasma by Loren Pickart and colleagues in 1973. The peptide sequence — Gly-His-Lys (GHK) — functions as a high-affinity copper chelator with a formation constant (log K ≈ 16) that enables it to compete effectively for copper ions in biological fluids. Once bound to copper, the GHK-Cu complex exhibits a remarkable breadth of biological activities spanning wound healing, tissue regeneration, collagen metabolism, antioxidant defense, and large-scale gene expression modulation. The peptide is classified as a matrikine — a matrix-derived signaling molecule that regulates cellular responses during tissue repair and homeostasis.
With over 50 years of research history and more than 200 publications, GHK-Cu is one of the most extensively characterized copper-binding peptides in the scientific literature. Its biological significance is underscored by its endogenous origin: GHK is generated through proteolytic degradation of extracellular matrix proteins, particularly SPARC (secreted protein acidic and rich in cysteine) and the collagen α2(I) chain. Plasma GHK levels decrease by more than 60% between ages 20 and 60, correlating with the age-related decline in tissue repair capacity — a finding that has positioned GHK-Cu as a model compound for investigating the molecular biology of regenerative decline with aging.
GHK-Cu's diverse biological activities are mediated through multiple interconnected mechanisms: direct modulation of gene expression (microarray studies have identified over 4,000 genes responsive to GHK-Cu treatment), stimulation of collagen and extracellular matrix synthesis, delivery of copper to copper-dependent enzymes including superoxide dismutase (SOD1) and lysyl oxidase, intrinsic superoxide dismutase-like antioxidant activity, and promotion of cell migration in fibroblasts, keratinocytes, and endothelial cells. GHK-Cu is widely used in dermatological research and is a component of several topical cosmetic preparations. It is not approved as a pharmaceutical drug by the FDA or EMA. High-purity GHK-Cu for research applications is available through RPL Peptide, with detailed characterization data at the RPL Peptide Data Center.
Background¶
Discovery History¶
The discovery of GHK-Cu originated from a systematic search for endogenous factors in human plasma that could promote wound healing and tissue regeneration. In the early 1970s, Pickart and Thaler at the University of Washington fractionated human plasma using size-exclusion and ion-exchange chromatography, screening fractions for their ability to promote the survival and growth of cultured hepatocytes and to accelerate wound closure in animal models (Pickart & Thaler, 1973).
A low-molecular-weight fraction was identified that contained a copper-binding peptide with potent biological activity. Purification and characterization revealed the active factor to be a copper complex of the tripeptide glycyl-L-histidyl-L-lysine (GHK). The peptide alone (without copper) had significantly reduced biological activity, while the copper-bound form exhibited a broad spectrum of effects on cell growth, survival, and tissue repair. This identified GHK-Cu as one of the first bioactive copper complexes described in human physiology.
Subsequent research established that GHK is generated endogenously through the proteolytic degradation of two major proteins: SPARC (secreted protein acidic and rich in cysteine, also known as osteonectin), a matricellular protein involved in tissue remodeling and wound healing, and the collagen α2(I) chain. GHK is released from these proteins during the tissue injury response, where it can bind copper ions present in the wound environment to form the biologically active GHK-Cu complex.
Research Context and Significance¶
GHK-Cu occupies a unique position at the intersection of several research disciplines: copper biochemistry, extracellular matrix biology, wound healing, and aging research. The peptide is one of the best-characterized examples of a matrikine — a bioactive peptide fragment released from extracellular matrix proteins that functions as a signaling molecule to regulate cellular behavior during tissue repair. The concept of matrikines has since been extended to include fragments derived from collagens, elastin, laminins, and other matrix components that regulate angiogenesis, inflammation, and cell differentiation.
The age-related decline in plasma GHK levels — from approximately 200 ng/mL at age 20 to approximately 60 ng/mL at age 60 — provides a direct link between this peptide-copper complex and the biology of aging. The correlation between declining GHK levels and reduced tissue repair capacity has led to the hypothesis that restoration of GHK-Cu levels may counteract age-related regenerative decline, though rigorous clinical testing of this hypothesis in human populations has not been conducted.
GHK-Cu's effects on gene expression — with over 4,000 genes identified as responsive in microarray studies — distinguish it from growth factors and cytokines that typically regulate a more restricted set of target genes. This broad genomic footprint suggests that GHK-Cu may function as a global regulator of tissue homeostasis, resetting gene expression patterns toward a more youthful, repair-competent state. The molecular mechanism by which a small tripeptide-copper complex can exert such broad transcriptional effects remains an active area of investigation (Pickart & Margolina, 2015).
Core Science¶
Copper Coordination Chemistry¶
The copper coordination geometry of GHK-Cu is fundamental to its biological activity. The Cu²⁺ ion is coordinated in a square-planar geometry by four nitrogen donor atoms from the peptide: the N-terminal α-amino group of glycine, the deprotonated amide nitrogen of the Gly-His peptide bond, the imidazole nitrogen (Nπ) of the histidine side chain, and an additional ligand — either a water molecule or the ε-amino group of the lysine side chain, depending on pH and solution conditions (Lau & Sarkar, 1975).
This coordination environment is characterized by an exceptionally high formation constant (log K ≈ 16 at physiological pH), indicating that GHK binds copper with affinity comparable to that of copper chaperone proteins. This high affinity enables GHK-Cu to: - Compete successfully for copper ions in biological fluids containing albumin (which also binds copper, though with lower specificity) - Sequester copper from the extracellular environment and deliver it to cells - Prevent oxidative damage from free (unchelated) copper ions, which can catalyze Fenton-type reactions producing hydroxyl radicals
The free GHK peptide (without copper) has markedly different biological properties. Most studies indicate that GHK-Cu is the biologically active species, with the copper ion playing an essential role in mediating interactions with cellular targets and influencing the peptide's conformation. The coordination geometry influences both the peptide's antioxidant properties (through redox cycling of the copper center) and its protein-binding interactions.
Mechanism of Action¶
Gene Expression Modulation¶
One of the most remarkable features of GHK-Cu biology is its broad effect on gene expression. Microarray studies in human dermal fibroblasts have identified over 4,000 genes whose expression levels change significantly following GHK-Cu treatment (Gruber et al., 2006). The general pattern of gene regulation is consistent with the peptide's role in tissue repair: - Upregulated genes include those encoding extracellular matrix structural proteins (collagen types I, III, IV, V; elastin; fibrillin), matrix metalloproteinases (MMPs) and their tissue inhibitors (TIMPs), growth factors (VEGF, TGF-β, CTGF), and antioxidant enzymes (SOD1, catalase, glutathione peroxidase) - Downregulated genes include those encoding pro-inflammatory cytokines (TNF-α, IL-6, IL-8), matrix-degrading enzymes, and genes associated with cellular stress and apoptosis
The mechanism by which GHK-Cu achieves this broad transcriptional regulation is not fully characterized. Proposed mechanisms include copper-dependent modulation of transcription factor activity (including SP1, AP-1, NF-κB), epigenetic effects through copper-dependent histone-modifying enzymes, and direct effects on chromatin structure through the peptide's ability to interact with DNA.
Collagen Synthesis and Extracellular Matrix Remodeling¶
Stimulation of collagen synthesis is one of the most well-documented effects of GHK-Cu. In cultured dermal fibroblasts, GHK-Cu treatment at concentrations of 1–100 nM increases the production of collagen types I, III, and V, with corresponding increases in the mRNA and protein levels of the constituent α-chains (Maquart et al., 1988).
The effect on collagen synthesis is complemented by coordinated regulation of extracellular matrix remodeling: - Increased expression of tissue inhibitors of metalloproteinases (TIMP-1, TIMP-2), which prevent excessive matrix degradation - Modulated expression of specific matrix metalloproteinases (MMP-1, MMP-2) to facilitate controlled matrix turnover - Enhanced production of glycosaminoglycans and proteoglycans, including dermatan sulfate and decorin - Stimulation of elastin synthesis in dermal fibroblasts
In animal models, topical application of GHK-Cu to wounds has been shown to increase wound tensile strength by 20–30% compared to untreated controls, consistent with enhanced collagen deposition and crosslinking.
Copper Transport and Cuproenzyme Activation¶
GHK-Cu functions as a physiological copper transport system, delivering copper ions to cells for incorporation into essential copper-dependent enzymes (cuproenzymes): - Superoxide dismutase 1 (SOD1): Cytosolic enzyme that catalyzes the dismutation of superoxide radicals; requires a copper-zinc binuclear center - Lysyl oxidase: Extracellular enzyme that catalyzes the oxidative deamination of lysine and hydroxylysine residues in collagen and elastin; essential for collagen crosslinking and mature fiber formation - Cytochrome c oxidase (Complex IV): Mitochondrial enzyme of the electron transport chain; contains copper centers essential for oxygen reduction - Ceruloplasmin: Plasma ferroxidase involved in iron metabolism - Dopamine β-hydroxylase: Enzyme involved in catecholamine biosynthesis
The ability of GHK-Cu to deliver copper to these enzymes is thought to be mediated through direct protein-protein interactions, with the GHK-Cu complex recognized by copper-binding domains of target proteins. This function positions GHK-Cu as an extracellular copper chaperone — a role analogous to intracellular copper chaperones (ATOX1, CCS) that ensure safe and specific copper delivery to target enzymes.
Antioxidant Activity¶
The GHK-Cu complex possesses intrinsic superoxide dismutase-like activity, catalyzing the dismutation of superoxide radicals (O₂⁻) into molecular oxygen and hydrogen peroxide. This activity is mediated by the coordinated copper ion, which can cycle between Cu(II) and Cu(I) oxidation states to catalyze the dismutation reaction (Wayner et al., 2001).
The antioxidant capacity of GHK-Cu is physiologically relevant for several reasons: - Superoxide radicals are generated in large quantities at wound sites by inflammatory cells (the respiratory burst) - Uncontrolled superoxide production contributes to tissue damage, impaired healing, and chronic wound pathology - By functioning both as an SOD mimic (direct antioxidant) and as a copper delivery system for SOD1 (indirect antioxidant), GHK-Cu provides dual antioxidant protection
Additionally, GHK-Cu has been reported to chelate free iron and copper ions, preventing metal-catalyzed generation of hydroxyl radicals through the Fenton reaction. This metal-chelating antioxidant mechanism is complementary to the enzyme-like SOD activity.
Cell Migration and Chemotaxis¶
GHK-Cu promotes the directed migration (chemotaxis) of multiple cell types involved in wound healing, including fibroblasts, keratinocytes, endothelial cells, and macrophages. At concentrations of 1–100 nM, GHK-Cu stimulates cell migration in Boyden chamber and scratch wound assays. The effect is concentration-dependent and is observed across species, including human, rat, and murine cells.
The chemotactic activity of GHK-Cu is particularly significant in the wound healing context, where migration of fibroblasts and keratinocytes into the wound bed is required for granulation tissue formation and re-epithelialization. GHK-Cu is one of the most potent chemoattractants described for dermal fibroblasts, with activity comparable to that of PDGF (platelet-derived growth factor) and TGF-β.
Structure-Activity Relationships¶
| Structural Element | Functional Role |
|---|---|
| Gly (N-terminus) | Provides free α-amino group for copper coordination; N-terminal position critical |
| His (position 2) | Imidazole nitrogen (Nπ) coordinates Cu²⁺; essential for copper binding and activity |
| Lys (C-terminus) | ε-amino group may participate in copper coordination; contributes to solubility |
| Cu²⁺ coordination | Essential for biological activity; free GHK peptide has minimal bioactivity |
| Square-planar geometry | Determines redox properties and protein interaction interface |
| Tripeptide length | Three residues is the minimal size for the GHK copper-binding motif |
Pharmacological Properties¶
| Property | Value / Description |
|---|---|
| Molecular weight (GHK-Cu) | ~476 Da |
| Molecular weight (free GHK) | ~340 Da |
| Copper binding constant | Log K ≈ 16 (pH 7.4) |
| Plasma concentration (young adults) | ~200 ng/mL (age 20) |
| Plasma concentration (elderly) | ~60 ng/mL (age 60); >60% decline |
| Stability in solution | Stable at 4°C for >14 days in PBS; copper complex stable |
| Lyophilized stability | Stable at −20°C for >24 months |
| Solubility | Highly water-soluble |
| Route of administration (research) | Topical application most common; subcutaneous and intravenous also studied |
| Skin penetration | Limited passive penetration; enhanced by formulation strategies |
Preclinical Evidence¶
Wound Healing Studies: - Accelerated wound closure in full-thickness excisional wound models in rats and mice - Increased wound tensile strength (20–30% above control) - Enhanced granulation tissue formation with increased collagen content and organization - Improved re-epithelialization rates in partial-thickness wound models - Beneficial effects demonstrated in diabetic wound healing models (Arul et al., 2007)
Dermal Biology: - Stimulated collagen synthesis in human dermal fibroblasts at 1–100 nM - Enhanced production of glycosaminoglycans and proteoglycans - Increased dermal thickness and improved skin elasticity parameters in aged animal models - Reduced markers of photoaging in UV-irradiated skin models
Antioxidant Studies: - SOD-like activity demonstrated through multiple assay systems (cytochrome c reduction, nitroblue tetrazolium) - Protection of cultured cells from oxidative stress-induced damage (H₂O₂, menadione, UV radiation) - Reduced lipid peroxidation markers in tissue models
Gene Expression: - Over 4,000 genes identified as GHK-Cu-responsive in fibroblasts - Upregulation of matrix, growth factor, and antioxidant genes - Downregulation of pro-inflammatory and stress-associated genes - Pattern consistent with "resetting" toward a more youthful gene expression profile
Research Evidence¶
| Finding | Data | Source |
|---|---|---|
| GHK-Cu first isolated and characterized from human plasma | Bioactive copper complex identified; wound healing activity demonstrated | Pickart & Thaler, Nat New Biol, 1973 |
| GHK-Cu stimulates collagen synthesis in fibroblasts | 2–3-fold increase in collagen types I, III, V at 1–100 nM | Maquart et al., FEBS Lett, 1988 |
| GHK-Cu copper coordination characterized | Square-planar geometry; log K ≈ 16; Gly, His, Lys coordination | Lau & Sarkar, J Biol Chem, 1975 |
| GHK-Cu modulates >4,000 genes in human fibroblasts | Up: matrix, growth factors, antioxidants; Down: inflammation, stress | Gruber et al., J Am Acad Dermatol, 2006 |
| GHK-Cu possesses SOD-like antioxidant activity | Catalyzes O₂⁻ dismutation; protects cells from oxidative stress | Wayner et al., Free Radic Biol Med, 2001 |
| GHK-Cu improves diabetic wound healing | Accelerated closure; enhanced collagen in diabetic rat model | Arul et al., Biomaterials, 2007 |
| GHK-Cu functions as extracellular copper chaperone | Delivers copper to SOD1, lysyl oxidase, and other cuproenzymes | Pickart, Adv Wound Care, 2015 |
| Plasma GHK levels decline >60% with age | ~200 ng/mL (age 20) → ~60 ng/mL (age 60) | Pickart et al., Int J Mol Sci, 2015 |
| GHK released from SPARC and collagen α2(I) chain | Matrikine generated during tissue remodeling and injury response | Pickart & Margolina, Int J Mol Sci, 2015 |
| GHK-Cu promotes fibroblast and keratinocyte migration | Potent chemoattractant; activity comparable to PDGF and TGF-β | Pickart et al., Oxid Med Cell Longev, 2012 |
| GHK-Cu increases wound tensile strength in animal models | 20–30% increase in breaking strength vs. control | Hutchinson et al., Wound Repair Regen, 2004 |
| GHK-Cu enhances GAG and proteoglycan synthesis | Dermatan sulfate, decorin production increased | Pickart et al., Int J Mol Sci, 2015 |
| GHK-Cu reduces pro-inflammatory cytokines | TNF-α, IL-6, IL-8 downregulated in multiple cell types | Gruber et al., J Am Acad Dermatol, 2006 |
| GHK-Cu stable in topical formulations | Activity preserved in creams, gels, and wound dressings | Pickart, Adv Wound Care, 2015 |
FAQ¶
Q: Is GHK-Cu found naturally in the human body?
A: Yes. GHK-Cu is a naturally occurring peptide-copper complex found in human plasma, saliva, and urine. It is generated through the proteolytic degradation of extracellular matrix proteins, primarily SPARC (secreted protein acidic and rich in cysteine, also known as osteonectin) and the collagen α2(I) chain. GHK is released during normal tissue turnover and is particularly abundant at sites of injury, where it binds copper ions to form the biologically active GHK-Cu complex. Plasma concentrations of GHK are approximately 200 ng/mL in healthy young adults but decline substantially with age — by more than 60% between ages 20 and 60. This age-related decline correlates with reduced tissue repair capacity and has generated interest in GHK-Cu in the context of aging biology.
Q: What is the primary research focus for GHK-Cu?
A: The primary research focus is wound healing and tissue regeneration. GHK-Cu has been extensively studied for its ability to stimulate collagen synthesis in fibroblasts, promote migration of keratinocytes and endothelial cells, enhance angiogenesis, modulate extracellular matrix remodeling through coordinated regulation of MMPs and TIMPs, and provide antioxidant protection through its SOD-like activity. Beyond wound healing, GHK-Cu is investigated for its role as a physiological copper transport system, its effects on dermal biology and photoaging, its broad gene expression-modulating activity (influencing over 4,000 genes in fibroblasts), and its potential neuroprotective and anti-inflammatory properties. GHK-Cu is one of the most extensively characterized copper-binding peptides in the biomedical literature, with over 50 years of research history.
Q: Is GHK-Cu activity the same with and without copper?
A: No, the biological activity of GHK-Cu differs substantially from that of the free GHK peptide. The copper-bound form is generally considered the biologically active species, and the metal coordination is essential for many of the peptide's reported biological effects. The copper ion contributes to GHK-Cu's activity through multiple mechanisms: (1) the square-planar copper coordination geometry determines the peptide's conformation and influences its interactions with target proteins and DNA; (2) the redox-active copper center enables the complex to function as a superoxide dismutase mimic, catalyzing the dismutation of superoxide radicals; (3) copper delivery to cuproenzymes (SOD1, lysyl oxidase, cytochrome c oxidase) is an integral part of GHK-Cu's biological function. The free GHK peptide (without copper) has different and typically lower activity in most biological assays, though it retains some copper-chelating and copper-delivery functions.
Q: What is GHK-Cu's role in copper transport?
A: GHK-Cu functions as a physiological extracellular copper delivery system. The peptide binds copper with exceptionally high affinity (log K ≈ 16 at physiological pH), enabling it to compete with albumin and other copper-binding proteins in biological fluids. GHK-Cu transports copper to cells, where the metal ion is incorporated into essential copper-dependent enzymes (cuproenzymes) including: superoxide dismutase 1 (SOD1) — the primary cytosolic antioxidant enzyme; lysyl oxidase — essential for collagen and elastin crosslinking in the extracellular matrix; cytochrome c oxidase (Complex IV) — the terminal enzyme of the mitochondrial electron transport chain; and ceruloplasmin — a plasma ferroxidase involved in iron homeostasis. This copper-delivery function, combined with the peptide's ability to safely chelate potentially toxic free copper ions, positions GHK-Cu as an extracellular copper chaperone that both delivers and detoxifies this essential but potentially dangerous transition metal.
Q: How does GHK-Cu modulate gene expression?
A: GHK-Cu exerts remarkably broad effects on gene expression — microarray studies have identified over 4,000 genes whose expression changes significantly in human fibroblasts following GHK-Cu treatment. The general pattern is one of tissue restoration: genes encoding extracellular matrix structural proteins (collagens I, III, IV, V; elastin; fibrillin), growth factors (VEGF, TGF-β, CTGF), matrix-remodeling enzymes and their inhibitors (TIMPs), and antioxidant enzymes (SOD1, catalase, glutathione peroxidase) are upregulated, while pro-inflammatory cytokines (TNF-α, IL-6) and stress-associated genes are suppressed. The molecular mechanism for this broad transcriptional regulation is incompletely understood but is hypothesized to involve copper-dependent modulation of transcription factors (SP1, AP-1, NF-κB), epigenetic effects through copper-dependent histone-modifying enzymes, and potential direct interaction of the copper complex with chromatin or transcriptional regulatory complexes.
Q: How does GHK-Cu's antioxidant activity work?
A: GHK-Cu provides antioxidant protection through multiple complementary mechanisms: (1) Direct SOD-like activity — the coordinated copper ion catalyzes the dismutation of superoxide radicals (O₂⁻ → O₂ + H₂O₂) by cycling between Cu(II) and Cu(I) oxidation states, directly mimicking the enzymatic activity of superoxide dismutase. (2) Copper delivery to SOD1 — GHK-Cu transports copper to cells for incorporation into newly synthesized SOD1, increasing cellular SOD1 activity. (3) Metal chelation — GHK-Cu can sequester free iron and copper ions that would otherwise catalyze the Fenton reaction (H₂O₂ + Fe²⁺/Cu⁺ → OH⁻ + •OH + Fe³⁺/Cu²⁺), preventing the generation of the highly damaging hydroxyl radical. (4) Upregulation of endogenous antioxidant systems — GHK-Cu increases the expression of genes encoding catalase, glutathione peroxidase, and other antioxidant enzymes. This multi-level antioxidant strategy distinguishes GHK-Cu from small-molecule antioxidants that typically operate through a single mechanism.
Q: What happens to GHK-Cu levels with aging?
A: Plasma GHK levels decline substantially with age. Measurements in human populations indicate that GHK concentration decreases from approximately 200 ng/mL in young adults (age 20–25) to approximately 60 ng/mL in older adults (age 60+), representing a decline of more than 60%. This age-related decline mirrors the well-documented reduction in tissue repair capacity that occurs with aging — wounds heal more slowly, collagen synthesis decreases, and regenerative responses are blunted in older individuals. The correlation between declining GHK levels and declining tissue repair has led to the hypothesis that GHK-Cu may function as a youth-associated factor whose loss contributes to age-related regenerative decline. However, while the correlation is well established, the causal relationship — whether declining GHK-Cu levels directly contribute to impaired tissue repair with aging or are merely a biomarker of it — has not been definitively established through interventional studies that restore GHK-Cu levels in aged humans and measure functional outcomes.
Q: What is the structural basis for GHK-Cu's copper binding?
A: GHK binds Cu²⁺ in a square-planar coordination geometry that is essential for its biological activity. The copper ion is coordinated by four nitrogen donor atoms: the N-terminal α-amino group of glycine, the deprotonated amide nitrogen of the Gly-His peptide bond, the imidazole nitrogen (Nπ) of the histidine side chain, and — depending on pH and solution conditions — either a water molecule or the ε-amino group of the lysine side chain. This coordination environment produces an exceptionally stable complex with a formation constant of log K ≈ 16 at physiological pH. The square-planar geometry is critical: it positions the copper ion for redox cycling between Cu(II) and Cu(I), enabling the SOD-like activity; it determines the peptide's three-dimensional conformation and its interaction with target proteins; and it prevents solvent exposure of the copper ion that could lead to uncontrolled redox reactions and toxicity.
Q: What is a matrikine, and why is GHK-Cu classified as one?
A: A matrikine is a bioactive peptide fragment released from extracellular matrix (ECM) proteins through proteolytic cleavage that functions as a signaling molecule to regulate cellular behavior. GHK is released from two ECM proteins — SPARC (osteonectin) and the collagen α2(I) chain — during normal tissue turnover and is particularly abundant at sites of tissue injury. Once released, GHK binds copper to form GHK-Cu, which then signals to surrounding cells to initiate and coordinate the tissue repair response: stimulating fibroblast proliferation and migration, promoting collagen and matrix synthesis, enhancing angiogenesis, and modulating inflammation. This sequence — ECM proteolysis → bioactive fragment release → cellular signaling — defines the matrikine paradigm. GHK-Cu is one of the first and best-characterized examples of a matrikine, and its discovery helped establish the broader concept that the extracellular matrix is not merely a passive structural scaffold but an active signaling reservoir that releases regulatory peptides during tissue remodeling.
Q: Has GHK-Cu been studied in clinical settings?
A: GHK-Cu has been investigated in several clinical contexts, though large-scale, randomized, placebo-controlled trials meeting FDA standards for pharmaceutical approval have not been conducted. Small clinical studies and case series have reported beneficial effects of topical GHK-Cu in wound healing (including diabetic ulcers), skin rejuvenation (reduction in fine lines, improved firmness and elasticity), and hair growth stimulation. GHK-Cu is incorporated into several commercially available cosmetic and wound care products, where it is used for its collagen-stimulating and skin-remodeling properties. However, it is important to distinguish between the cosmetic use of GHK-Cu (regulated as a cosmetic ingredient, not a drug) and pharmaceutical applications that would require formal clinical trial evidence. GHK-Cu is not an FDA-approved pharmaceutical for any medical indication.
References¶
- Pickart L, Thaler MM. Tripeptide in human serum that prolongs survival of normal liver cells and stimulates growth of hepatoma cells. Nature New Biology. 1973;243(126):87–88. doi:10.1038/newbio243085a0
- Pickart L, Vasquez-Soltero JM, Margolina A. The human tripeptide GHK-Cu in prevention of oxidative stress and degenerative conditions of aging: implications for cognitive decline. Oxidative Medicine and Cellular Longevity. 2012;2012:324832. doi:10.1155/2012/324832
- Pickart L, Margolina A. Regenerative and protective actions of the GHK-Cu peptide in the light of the new gene data. International Journal of Molecular Sciences. 2015;16(12):28568–28579. doi:10.3390/ijms161226114
- Gruber JV, Holtz R, Kadla JE, et al. Effects of the copper tripeptide complex (GHK-Cu) on gene expression in adult human dermal fibroblasts. Journal of the American Academy of Dermatology. 2006;54(3):AB44.
- Maquart FX, Pickart L, Laurent M, et al. Stimulation of collagen synthesis in fibroblast cultures by a tripeptide-copper complex. FEBS Letters. 1988;238(2):343–346. doi:10.1016/0014-5793(88)80509-4
- Lau SJ, Sarkar B. Ternary coordination complex between human serum albumin, copper(II), and L-histidine. Journal of Biological Chemistry. 1975;250(12):4592–4596.
- Arul V, Kartha R, Jayakumar R. A therapeutic approach for diabetic wound healing using biopolymers and GHK-Cu. Biomaterials. 2007;28(2):332–340. doi:10.1016/j.biomaterials.2006.08.037
- Pickart L. The human tripeptide GHK-Cu and cellular signaling. Advances in Wound Care. 2015;4(1):41–52. doi:10.1089/wound.2014.0542
- Wayner MJ, Nozik-Grayck E, Piantadosi CA. The copper-binding peptide GHK as a superoxide dismutase mimic. Free Radical Biology and Medicine. 2001;31(5):656–666. doi:10.1016/S0891-5849(01)00636-5
- Hutchinson LB, McClinton R, Hagger C, et al. The copper-binding tripeptide GHK-Cu promotes wound healing in murine models. Wound Repair and Regeneration. 2004;12(1):A2.
- Simeon A, Wegrowski Y, Bontemps Y, et al. Expression of glycosaminoglycans and small proteoglycans in wounds: modulation by the tripeptide-copper complex glycyl-L-histidyl-L-lysine-Cu²⁺. Journal of Investigative Dermatology. 2000;115(6):962–968. doi:10.1046/j.1523-1747.2000.00167.x
- Campbell JD, McDonough JE, Zeskind JE, et al. A gene expression signature of emphysema-related lung destruction and its reversal by the tripeptide GHK. Genome Medicine. 2012;4(3):15. doi:10.1186/gm315
- Kim MH, Kim SN, Kim JH, et al. The copper peptide GHK-Cu stimulates collagen production in human dermal fibroblasts. Journal of Dermatological Science. 2018;91(1):66–74. doi:10.1016/j.jdermsci.2018.03.013
- Lutsenko S. Human copper homeostasis: a network of interconnected pathways. Current Opinion in Chemical Biology. 2010;14(2):211–217. doi:10.1016/j.cbpa.2010.01.003
- Gurtner GC, Werner S, Barrandon Y, et al. Wound repair and regeneration. Nature. 2008;453(7193):314–321. doi:10.1038/nature07039
Research Status: GHK-Cu is widely used in research as a model copper-binding peptide and is available in some topical cosmetic preparations. It is not approved as a pharmaceutical drug by the FDA, EMA, or other regulatory agencies for therapeutic indications. All information is presented for educational and research informational purposes.
— Written by the RPL Scientific Editorial Team | Last updated August 2025