GHK-Cu, the tripeptide glycine-histidine-lysine complexed with copper, was first isolated from human plasma by Loren Pickart in 1973. Pickart observed that plasma from a 22-year-old donor significantly stimulated liver tissue function compared to plasma from a 60-year-old, and identified GHK-Cu as the active component. Subsequent decades of research have established GHK-Cu as one of the most biologically active naturally occurring peptide-metal complexes known, with documented effects on wound healing, collagen synthesis, anti-inflammatory signalling, antioxidant activity, and gene expression across dozens of tissue types. The Glow blend typically refers to a formulation combining GHK-Cu with complementary peptides targeted at skin quality and anti-ageing.
Effects on Collagen and Skin Architecture
GHK-Cu stimulates synthesis of collagen, elastin, and glycosaminoglycans including hyaluronic acid, the three primary structural components of the dermal extracellular matrix that are progressively lost with age. It activates matrix metalloproteinases that break down damaged collagen, allowing its replacement with newly synthesised intact collagen. Simultaneously it inhibits the TGF-beta pathway that drives fibrosis and scar formation, resulting in improved remodelling toward functional rather than scarred tissue. In human clinical studies of topical GHK-Cu, measurable increases in skin density, thickness, and elasticity have been demonstrated alongside visible reduction in fine lines and improved skin tone.
Gene Expression Effects
Pickart and colleagues performed gene expression analysis showing that GHK-Cu modulates the expression of over 4,000 human genes, approximately 31 per cent of the human genome genes analysed. The pattern of modulation is broadly anti-ageing: it upregulates genes associated with tissue repair, antioxidant defence, mitochondrial function, and stem cell activation, while downregulating genes associated with inflammation, cancer progression, and tissue degradation. This broad gene expression effect has led researchers to propose GHK-Cu as a potential systemic anti-ageing intervention, not merely a topical skincare ingredient, though systematic human clinical trial evidence for systemic administration remains limited.
The Glow Blend
Commercial Glow blends for skin and anti-ageing purposes typically combine GHK-Cu with epithalon, a tetrapeptide studied for its telomerase-activating and pineal gland-regulating properties; collagen peptides including types I and III; and sometimes sermorelin or similar growth hormone secretagogues for their effects on skin thickness and texture. The rationale is addressing skin ageing from multiple angles simultaneously: extracellular matrix support from GHK-Cu, telomere protection from epithalon, structural collagen from dietary collagen peptides, and growth hormone-mediated skin thickness maintenance from secretagogue inclusion.
Topical Versus Systemic Administration
GHK-Cu is most extensively researched in topical application and is a well-established ingredient in premium skincare formulations. Topical penetration into the dermis is documented and its effects on local collagen synthesis are well established. Subcutaneous and intravenous administration have been studied primarily in research contexts and are proposed to produce systemic effects on organ systems beyond the skin. The topical route is the most accessible, best-evidenced, and lowest-risk approach for most people. Formulations containing 2 to 5 per cent GHK-Cu have shown the most consistent clinical effects in skin studies.