What is GHK-Cu?
GHK-Cu (glycyl-L-histidyl-L-lysine-copper) is a naturally occurring tripeptide-copper complex found in human plasma, saliva, and urine that declines with age, but it currently lacks established clinical guidelines, safety data, or FDA approval for therapeutic use. 1
Biochemical Properties
- GHK is a tripeptide consisting of glycine, histidine, and lysine that has high affinity for copper(II) ions, forming the chelate complex GHK-Cu 2, 3
- Plasma levels average approximately 200 ng/ml at age 20 but decline to around 80 ng/ml by age 60 4
- The molecule exists both as copper-free GHK and as the copper complex GHK-Cu, with both forms showing biological activity 5
Proposed Biological Mechanisms (Research-Based)
- GHK-Cu stimulates synthesis and breakdown of collagen, glycosaminoglycans (particularly dermatan sulfate and heparan sulfate), and the small proteoglycan decorin 2, 6
- The compound modulates metalloproteinase activity and their inhibitors, affecting tissue remodeling 2
- Research suggests it can up- and downregulate thousands of human genes, potentially affecting epigenetic pathways 2, 3
- In vitro studies show antioxidant and anti-inflammatory properties 3, 4
Lack of Clinical Evidence and Guidelines
- No major medical societies (European League Against Rheumatism, American College of Rheumatology) include GHK-Cu in their treatment guidelines 1
- The safety profile, appropriate dosing, drug interactions, and long-term effects in humans remain unknown 1
- Most evidence comes from in vitro studies, animal models, and cosmetic applications rather than rigorous clinical trials 2, 4
Current Applications (Non-Medical)
- GHK-Cu is used in cosmetic products for skin care, where it has been reported to improve skin elasticity, reduce wrinkles, and increase keratinocyte proliferation 2, 5
- Research shows wound healing effects in animal models (rats, mice, pigs, dogs) but human clinical data is limited 2
Critical Caveats
- The compound is not FDA-approved for therapeutic injection or systemic use 1
- Copper toxicity is a concern, particularly in patients with abnormal liver function or cholestasis, as copper is primarily excreted through bile 7
- The relationship between copper-free GHK and copper-GHK effects requires further clarification 5
- Proposed therapeutic uses for neurodegeneration, COPD, and cancer remain purely speculative without clinical trial data 2, 3