September 5, 2026 · 2 min read
GHK-Cu: the copper-binding tripeptide and what its skin and wound research shows
GHK is a three-amino-acid peptide that binds copper. A research overview of its reported effects on wound healing and skin, and of who produced the evidence.
GHK is a tripeptide of glycine, histidine and lysine. It binds copper(II) tightly and forms GHK-Cu, the form usually studied. It occurs naturally in human blood, and that fact drives much of the interest in it.
The GHK sequence
Sequence: Glycine, Histidine, Lysine.
- Glycine or proline
- Positively charged
- Length
- 3 amino acids
- Average mass (peptide only)
- 340.38 Da
- Formula
- C14H24N6O4
It declines with age
A 2020 review reports average serum GHK of about 200 ng/ml at age 20, falling to about 80 ng/ml by age 60. That decline is the basis for the hypothesis that GHK could be an anti-aging peptide. The same review is careful to call the evidence a rationale for further preclinical and clinical study. It cites preliminary observations that GHK may partially reverse cognitive impairment in aging mice.
Average GHK in human serum
- Age 20200 ng/ml
- Age 6080 ng/ml
Tissue remodeling
Pickart's 2008 review describes GHK-Cu as activating a wide set of remodeling processes after the first phase of wound healing: attracting repair cells, damping inflammation, raising synthesis of collagen and elastin, and increasing proliferation of fibroblasts and keratinocytes. It also reports controlled studies on aged skin showing improved elasticity and firmness and fewer fine lines. A 1999 paper in the Journal of Investigative Dermatology looked at how the complex modulates matrix metalloproteinases in wounds.
Processes linked to GHK-Cu
Repair cell recruitment
Chemoattraction of macrophages, mast cells and capillary cells.
Less inflammation
Suppression of free radicals, TGF-beta 1 and TNF-alpha, among others.
More matrix protein
Higher collagen, elastin and metalloproteinase synthesis.
Cell growth
More fibroblast and keratinocyte proliferation, nerve outgrowth and angiogenesis.
A note on sourcing
Much of the positive literature comes from the group that discovered GHK and developed it, which is normal for a field this young but worth knowing. Newer reviews from 2026 cover topical microneedle delivery and formulation science, and one of them explicitly calls for expanded clinical trials. Reported skin results in particular depend on the formulation and the delivery method, so a result for one product doesn't transfer to another.
References
- Pickart L. The human tri-peptide GHK and tissue remodeling. J Biomater Sci Polym Ed 2008.
- Dou Y et al. The potential of GHK as an anti-aging peptide. Aging Pathobiol Ther 2020.
- Simeon A et al. Expression and activation of matrix metalloproteinases in wounds: modulation by the tripeptide-copper complex glycyl-L-histidyl-L-lysine-Cu2+. J Invest Dermatol 1999.
- Najafi N et al. A Systematic Review of the Mechanisms and Therapeutic Applications of GHK-Cu in Topical Microneedle Delivery. Arch Intern Med Res 2026.
Related research notes
- BPC-157: what the research actually covers, from rodent studies to the first human pilotsA look at the BPC-157 literature: how much is animal work, what the three small human studies reported, and why reviewers rate the evidence as very low.
- TB-500 and thymosin beta-4: separating the parent protein from the marketed fragmentThymosin beta-4 has decades of published work. TB-500, sold as a fragment of it, has very little. A research overview of where each stands.