GHK-Cu: Research Overview

GHK-Cu is the copper(II)-bound form of the tripeptide glycyl-L-histidyl-L-lysine (GHK). First isolated from human plasma in 1973 by Loren Pickart, GHK-Cu has been studied for its roles in wound healing, skin remodeling, anti-inflammatory signaling, and gene expression regulation. The predominant application in published literature and commercial practice is topical cosmetic dermatology; injectable use has far thinner evidence.

What Is GHK-Cu?

GHK (Gly-His-Lys) is a naturally occurring tripeptide found in human plasma, saliva, and urine. It has a high affinity for copper(II) ions, forming the complex GHK-Cu. At age 20, plasma GHK concentration is reported at approximately 200 ng/mL, declining to approximately 80 ng/mL by age 60. Its molecular weight is approximately 340 Da. GHK-Cu's primary research applications involve skin biology: it has been shown in cell culture and animal models to stimulate collagen and glycosaminoglycan synthesis, attract macrophages and mast cells to wound sites, and modulate metalloproteinase activity to promote tissue remodeling.

Mechanism of Action

GHK-Cu modulates gene expression broadly. Pickart et al. (2012–2015) reported that GHK regulates expression of more than 4,000 human genes in fibroblast studies, including upregulation of genes encoding collagen, elastin, fibronectin, and decorin, alongside downregulation of pro-inflammatory cytokines and oxidative stress markers. The copper component contributes to superoxide dismutase-like antioxidant activity and may facilitate wound-healing through enhanced angiogenesis. The precise cell-surface receptor mediating GHK-Cu’s effects has not been definitively characterized.

What the Research Shows

The majority of GHK-Cu research is in cell culture and animal models, predominantly studying topical application. Pickart and colleagues (BioMed Research International, 2015) reviewed evidence across wound healing, skin regeneration, and gene regulation, concluding that GHK-Cu promotes tissue repair and modulates a wide gene-expression network. A 2018 review in the International Journal of Molecular Sciences (PMID 29986520) further characterized GHK-Cu’s regenerative and anti-cancer-associated gene expression properties.

Human clinical data on GHK-Cu are largely limited to topical dermatology studies demonstrating improvements in skin texture, wrinkle depth, and elasticity with topical GHK-Cu-containing formulations. Controlled trials of injectable GHK-Cu in humans have not been published in the peer-reviewed literature. The evidence base for parenteral use is essentially absent.

Reported Dose Ranges

DISCLAIMER: The following information is provided for research reference only and is not medical advice or a recommendation to use this compound. Published literature on injectable GHK-Cu dosing in humans is very limited. The ranges below reflect preclinical and cosmetic topical literature and should not be extrapolated to human parenteral use.

GHK-Cu is most extensively studied and commercially used as a topical compound in skincare formulations, typically at concentrations of 0.5–2.0% in creams, serums, and shampoos. Published evidence for injectable (subcutaneous or intravenous) dose ranges in humans is absent from peer-reviewed sources. Research peptide vendors supply GHK-Cu in lyophilized form, but this market exists outside the context of clinical trials, and no controlled human PK or dose-finding study has been published.

Storage

Lyophilized GHK-Cu should be stored at 2–8 °C in a dark, dry environment; some preparations are stable at room temperature when desiccated. Reconstituted solutions should be stored at 2–8 °C and used within 28 days. Light exposure can degrade the copper complex over time.