Glycyl-L-Histidyl-L-Lysine-Copper Complex (GHK-Cu) is a naturally derived, copper-binding tripeptide that plays a significant role in tissue repair and remodeling. It was first identified in human plasma, where its concentration decreases with age, suggesting a link to the aging process. The peptide exhibits a high affinity for copper(II) ions, forming a stable complex that is central to its biological activity. GHK-Cu is recognized for its ability to promote wound healing, stimulate collagen and glycosaminoglycan synthesis, and exert antioxidant and anti-inflammatory effects, making it a molecule of considerable interest in regenerative medicine, dermatology, and aging research. Its significance lies in its pleiotropic actions, influencing multiple pathways involved in tissue homeostasis and repair.
Quick Facts
| Also Known As | GHK-Cu, Copper Peptide GHK, Copper Tripeptide-1, Gly-His-Lys-Cu(II), Alamin |
|---|---|
| Sequence | Gly-His-Lys |
| Molecular Formula | C14H24CuN6O4 |
| Molecular Weight | Approximately 401.9 Da (for GHK-Cu complex; theoretical average). |
Research Parameters
| Half-Life | Unknown for the intact complex in vivo; likely short (minutes to hours) due to peptide degradation. |
|---|---|
| Stability | Lyophilized powder is stable for at least 24 months when stored at -20°C, protected from light and moisture. After reconstitution in sterile or bacteriostatic water, the solution should be stored at 2-8°C and used within 7-14 days, although stability data can vary. |
| Solubility | Sterile Water or Bacteriostatic Water (0.9% NaCl). Soluble in aqueous solutions. |
| Vial Size | 10 mg |
| Storage (Lyophilized) | -20°C, protect from light and moisture. |
| Storage (Reconstituted) | 2-8°C (refrigerated), protected from light. Use within 7-14 days. |
| Typical Research Dose | Research doses are highly context-dependent. Topical research uses formulations in the 1-10 ppm range (equivalent to 1-10 mcg/mL). Systemic animal research doses are not well-standardized. |
| Cycle Parameters | Research protocols vary widely. Topical studies often involve daily application for 4-12 weeks. Systemic administration protocols in animal models are not standardized for cycles. |
| Amino Acid Count | 3 |
Mechanism of Action
The mechanism of action of GHK-Cu is multifaceted, primarily centered around its role as a copper transporter and signaling molecule that modulates gene expression and cellular processes. Copper is an essential cofactor for numerous enzymes involved in extracellular matrix formation and antioxidant defense.
Copper-Dependent Enzyme Activation: GHK-Cu delivers copper ions to enzymes such as lysyl oxidase (critical for collagen and elastin cross-linking), superoxide dismutase (SOD, an antioxidant enzyme), and cytochrome c oxidase (involved in cellular energy production).
Gene Expression Modulation: GHK-Cu upregulates the expression of genes related to tissue remodeling, including collagen types I, III, and IV, decorin, and metalloproteinases (MMPs) and their inhibitors (TIMPs), promoting a balanced matrix synthesis and degradation.
Anti-inflammatory and Antioxidant Pathways: The complex reduces the production of pro-inflammatory cytokines like TNF-α and TGF-β1, while increasing the synthesis of protective proteins. It also scavenges free radicals directly and via SOD activation.
Stem Cell and Growth Factor Activity: GHK-Cu promotes the mobilization and differentiation of stem cells and increases the synthesis of growth factors such as vascular endothelial growth factor (VEGF), supporting angiogenesis and tissue regeneration.
Research Applications
Wound Healing and Tissue Repair: Research demonstrates that GHK-Cu accelerates wound closure in animal models by enhancing collagen deposition, angiogenesis, and re-epithelialization. It modulates inflammatory responses to create a pro-healing environment.
Dermatology and Skin Aging: Studies show GHK-Cu improves skin firmness, elasticity, and reduces wrinkles by stimulating collagen and elastin synthesis. It also promotes the repair of photodamaged skin and improves the appearance of scars.
Anti-inflammatory and Antioxidant Effects: In vitro and in vivo research indicates GHK-Cu possesses significant antioxidant capacity, protecting cells from oxidative stress, and exerts anti-inflammatory actions by downregulating key inflammatory mediators.
Hair Growth: Preliminary research suggests GHK-Cu may stimulate hair follicle growth and prolong the anagen phase, potentially through its effects on growth factors and cellular metabolism in the dermal papilla.
Nerve Regeneration: Animal studies indicate GHK-Cu can promote neurite outgrowth and support the repair of peripheral nerves, highlighting its potential in neuroregenerative applications.
Safety & Side Effects
Based on animal studies and human topical clinical trials, GHK-Cu is generally well-tolerated. In topical applications, it is considered non-irritating and non-sensitizing for most individuals. Anecdotally, with topical use, minor skin irritation or transient redness has been rarely reported. No serious systemic side effects have been reported from topical use in research. Theoretical concerns for systemic administration would relate to copper overload, though the peptide is believed to regulate copper homeostasis. Long-term safety data for systemic use is lacking.
Dosage Information
Disclaimer: The following information is derived from published preclinical and clinical research studies only and is not a recommendation for human use.
In research settings, typical doses have varied. In cell culture and topical formulations, concentrations often range from 1-100 µM. In animal wound healing studies, topical application of gels or creams containing 1-10 ppm (mg/L) GHK-Cu has been used. For systemic research in animal models, doses are less standardized but have involved subcutaneous injection. Human clinical trials for topical skincare have used formulations with GHK-Cu at concentrations around 1-10 ppm applied daily. The primary routes of administration in research are topical and subcutaneous. Frequency is typically daily for topical applications, and protocol duration in studies has ranged from several weeks to months.
References
Pickart, L., et al. 'The human tripeptide GHK-Cu in prevention of oxidative stress and degenerative conditions of aging: implications for cognitive health.' Oxidative Medicine and Cellular Longevity, 2012.
Maquart, F.X., et al. 'Stimulation of collagen synthesis in fibroblast cultures by the tripeptide-copper complex glycyl-L-histidyl-L-lysine-Cu2+.' FEBS Letters, 1988.
Pickart, L. 'The human tri-peptide GHK and tissue remodeling.' Journal of Biomaterials Science, Polymer Edition, 2008.
Buffoni, F., et al. 'The copper-binding tripeptide GHK-Cu complex as a potential activator of angiogenesis for wound healing applications.' Journal of Peptide Science, 1995.
Leyden, J.J., et al. 'Skin care benefits of copper peptide containing facial creams.' Journal of Cosmetic Dermatology, 2002.
Siméon, A., et al. 'Expression of glycosaminoglycans and small proteoglycans in wounds: modulation by the tripeptide-copper complex glycyl-L-histidyl-L-lysine-Cu(II).' Journal of Investigative Dermatology, 2000.