In vitro
This study investigated the synthesis and biological activity of novel conjugates combining hyaluronic acid (HA) with the copper-binding tripeptide glycyl-l-histidyl-l-lysine (GHK) at varying loading ratios, forming GHK-HA conjugates. The conjugates were designed to address the individual limitations of HA and GHK, including susceptibility to hydrolytic degradation and oxidative stress. In vitro assays demonstrated that GHK-HA bound copper(II) ions effectively and showed enhanced antioxidant properties compared to the individual components alone. When complexed with copper, the conjugates promoted the expression and release of several growth and trophic factors, including brain-derived neurotrophic factor (BDNF), vascular endothelial growth factor (VEGF), and bone morphogenetic protein-2 (BMP-2), suggesting synergistic osteogenic and angiogenic potential. The study also explored a proposed mechanistic pathway, finding that copper's intracellular chaperones — CCS and Atox1 — translocated to the nucleus and appeared to function as transcription factors. Limitations include the exclusively in vitro nature of the experiments, meaning results cannot yet be extrapolated to animal models or human clinical outcomes. No in vivo validation was performed.
Bioconjugate chemistry · Mar 2025DOI ↗ Preclinical
This study developed a composite hydrogel wound dressing (termed "GEK") by combining two food-derived biomaterials — oxidized konjac glucomannan (OKGM) from konjac and egg white (EW) proteins — cross-linked via Schiff base bonds to create a self-healing scaffold. The natural tripeptide-copper complex glycyl-l-histidyl-l-lysine-Cu (GHK-Cu) was incorporated into this hydrogel matrix. Researchers characterized the material's mechanical, self-repairing, and adhesive properties, then evaluated its biological performance in vitro and in vivo (likely using rodent infected wound models). The study reports that the GEK hydrogel demonstrated antibacterial and anti-inflammatory activity, promoted hemostasis through tissue adhesion, and supported neovascularization and skin regeneration. The all-natural composition was highlighted for its biocompatibility and biodegradability, with the authors proposing it as a cost-effective clinical strategy for infected wound management. Key limitations include that this is a preclinical materials science study with no human clinical data; evidence of efficacy is derived from laboratory and animal experiments. The translation of these findings to human wound care remains to be established through clinical trials.
Biomaterials research · Feb 2025DOI ↗ Review
This review paper examines the current state of knowledge and methodology surrounding the skin permeation of GHK-Cu (glycyl-L-histidyl-L-lysine copper tripeptide), a naturally occurring cosmetically active compound (CAC) associated with properties such as reducing fine lines and wrinkles, improving skin elasticity, and tightening skin. The authors highlight a central challenge: GHK-Cu is relatively hydrophilic, which limits its ability to penetrate the lipophilic stratum corneum, the skin's outermost barrier. The paper reviews liposomal encapsulation as a strategy to improve GHK-Cu's skin permeation potential, and surveys existing methods used to study transdermal transport of CACs—both free and liposome-encapsulated. A key finding from the literature analysis is that research specifically examining liposome-mediated transport of GHK-Cu is sparse, representing a notable gap in the field. The authors argue this gap motivates further methodological development to better assess how liposomes affect GHK-Cu trafficking through skin layers. As a review, the paper synthesizes existing literature rather than presenting original experimental data, and it does not include clinical trials or controlled human studies. Its conclusions about efficacy are therefore inferential and limited by the quality and quantity of the underlying studies reviewed.
Molecules (Basel, Switzerland) · Jan 2025DOI ↗ In vitro
This study presents a novel analytical application of capillary electrophoresis coupled to inductively coupled plasma tandem mass spectrometry (CE-ICP-MS/MS) to investigate the encapsulation of the copper tripeptide complex GHK-Cu within liposomes — a delivery system commonly used in cosmetic formulations. Using an ethanol injection method to form liposomes, the researchers monitored copper (Cu) and phosphorus (P) signals to confirm liposome formation and quantify the concentration of GHK-Cu encapsulated within them. The study demonstrates that CE-ICP-MS/MS, valued for its high sensitivity and ability to preserve analytes in their intact chemical form under mild, physiologically compatible conditions, can be successfully applied in cosmetic science contexts. The authors propose this methodology could support the development and optimization of diverse liposomal cosmetic formulations. Importantly, this paper is a methodological/analytical chemistry study — it does not test GHK-Cu efficacy in humans or animals, make clinical claims, or evaluate biological outcomes. Its findings are limited to demonstrating an analytical technique for characterizing a cosmetic ingredient's encapsulation efficiency in a laboratory setting.
Electrophoresis · Oct 2024DOI ↗ Animal only
This study investigated whether the naturally occurring copper-binding peptide GHK-Cu (glycyl-L-histidyl-L-lysine copper complex) could reduce Alzheimer's disease (AD)-related pathology in a transgenic mouse model. Male and female 5xFAD mice — a well-established preclinical model of AD — were treated with intranasal GHK-Cu three times per week from 4 to 7 months of age, with a C57BL/6J background strain as context. The researchers assessed behavioral outcomes, amyloid plaque burden, and neuroinflammation markers. The study found that treated mice showed delayed cognitive impairment compared to untreated controls, along with reductions in amyloid plaques and lower levels of MCP1-associated inflammation in the frontal cortex and hippocampus. The authors suggest these findings justify further investigation of GHK-Cu as a potential AD therapeutic. Key limitations include the exclusively preclinical (animal) nature of the work — results in transgenic mouse models do not reliably predict outcomes in humans — and the fact that 5xFAD mice represent an aggressive, artificially accelerated form of amyloid pathology that may not fully reflect the complexity of human AD.
Aging pathobiology and therapeutics · Sep 2024DOI ↗ Preclinical
This study investigated whether the copper-bound tripeptide GHK-Cu (glycyl-l-histidyl-l-lysine-Cu²⁺) could reduce lung inflammation and fibrosis in silicosis — a serious occupational lung disease caused by chronic inhalation of crystalline silica (CS) with no approved specific treatment. Researchers first established a silicosis mouse model by exposing mice to CS, then assessed GHK-Cu's effects on lung inflammation and fibrosis. In parallel, they used the RAW264.7 macrophage cell line (an in vitro model of alveolar macrophages) to study cellular mechanisms. Using molecular docking and binding studies, they identified peroxiredoxin 6 (PRDX6) as a potential molecular target of GHK-Cu. The study reported that GHK-Cu bound to PRDX6 and attenuated CS-induced oxidative stress in alveolar macrophages, which was associated with reduced pulmonary inflammation and fibrosis in the mouse model. No significant systemic toxicity was observed in the treated animals. Key limitations include reliance on animal and cell-line models with no human clinical data, and the mechanistic link to PRDX6 requires further validation. The authors conclude that GHK-Cu warrants investigation as a potential therapeutic candidate for silicosis.
Redox biology · Jun 2024DOI ↗