GHK-Cu (Glycyl-L-Histidyl-L-Lysine-Copper)

GHK‑Cu is a naturally occurring tripeptide–copper complex studied for its regenerative, anti‑inflammatory, and skin‑repair properties across wound healing and cosmetic dermatology contexts.151617 Clinical and mechanistic literature suggests benefits for collagen production, dermal density, and visible signs of skin aging.

GHK is a tripeptide (glycyl‑L‑histidyl‑L‑lysine) present in human plasma, saliva, and urine, which typically functions as a chelator for copper(II), forming the biologically active GHK‑Cu complex.1617 Physiological GHK‑Cu levels decline with age, paralleling reductions in tissue repair capacity and dermal matrix quality.1716

In vitro and gene‑expression studies indicate that GHK‑Cu modulates a broad set of genes related to tissue remodeling, inflammation, and antioxidant defense, effectively shifting expression patterns toward a more youthful profile.1517 It has been shown to stimulate collagen and elastin synthesis, enhance angiogenesis, support stem‑cell–related markers, and promote keratinocyte proliferation in skin models.1617

Placebo‑controlled clinical studies in middle‑aged women have reported improved skin laxity, clarity, firmness, and wrinkle appearance with topical GHK‑Cu compared to vitamin C or retinoic acid creams.1716 A recent IRB‑approved trial using a GHK‑Cu topical gel formulation found an average 28% increase in collagen density after 3 months of daily application, with top‑quartile responses above 50%.15

• Cosmetic dermatology: facial wrinkles, laxity, pigmentation, and dermal density1617
• Wound healing and scar modulation in dermal injury models1716
• Broad epigenetic effects on aging‑related gene expression networks1517
• Potential systemic applications in tissue repair and anti‑aging (largely preclinical)

Many cosmetic studies are relatively small, short‑term, and sponsored by product developers, raising typical concerns about external validity and publication bias.161715 Evidence is strongest for topical use on photoaged skin; systemic safety and efficacy profiles for non‑topical administration remain poorly characterized.1716

1. Pickart L et al. Regenerative and protective actions of the GHK‑Cu peptide in the skin. Clin Cosmet Investig Dermatol. 2018.17
2. Pickart L. Facial studies of GHK‑Cu: placebo‑controlled trials comparing collagen stimulation and cosmetic outcomes. (Review section). 2015.16
3. Epigenetic mechanisms activated by GHK‑Cu increase skin collagen density: IRB‑approved human clinical trial of NEEL gel. 2023.15