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GHK-Cu Peptide: A Review of Mechanisms and Studies
May
GHK-Cu: The Science Behind Copper Peptide Hair Regeneration
Introduction
1.1 | What Is a Copper Peptide?
Peptides were first described in the early nineteenth century and have since become foundational components of modern biomedical research [1]. Among these, the copper tripeptide glycyl‐L‐histidyl‐L‐lysine (GHK‐Cu) represents one of the earliest and most extensively investigated bioactive peptides. GHK‐Cu was initially identified and developed by Loren Pickart in 1973 [2, 3]. Since its discovery, GHK‐Cu has garnered increasing attention for its diverse biological effects, particularly within aesthetic medicine, wound healing, and regenerative therapies.
This review examines the historical background, biological mechanisms, and expanding clinical relevance of GHK‐Cu, with emphasis on applications in skin rejuvenation, hair restoration, tissue repair, and regenerative medicine [4–21].
1.2 | Overview of Peptides
The term “peptide” originated in the early 1800s, following foundational work by Emil Fischer and Franz Hofmeister, who first characterized peptide chemical structures [1]. In 1901, Fischer and Fourneau successfully synthesized the first peptide—glycyl‐glycine—thereby establishing the structural framework for dipeptides, tripeptides, and larger polypeptides [1]. Continued advancements in biochemistry led to the development of a wide array of naturally occurring and synthetic peptides with diverse biological functions.
A major milestone in peptide research occurred in 1973 with the identification of the copper‐binding tripeptide GHK‐Cu by Loren Pickart, which later became a key focus in regenerative and aesthetic medicine research [2, 3]. Despite its early discovery, widespread commercial incorporation of copper peptides into topical skincare formulations did not occur until the late 1980s [1].
In cosmeceutical science, topical peptides are commonly classified into four primary functional categories: signal peptides, carrier peptides, neurotransmitter‐inhibiting peptides, and enzyme‐inhibiting peptides [1]. For effective topical activity, peptides typically require a molecular weight below 500 Da to facilitate penetration through the skin barrier and achieve biological efficacy [1].
© 2026 John Wiley & Sons Ltd.
1 of 5 Dermatological Reviews, 2026; 7:e70067
https://doi.org/10.1002/der2.70067
Carrier peptides—particularly copper‐ and manganese‐binding tripeptides—play a critical role in stabilizing and transporting trace elements essential for enzymatic activity, wound repair, and tissue regeneration [1, 5]. Among these, GHK‐Cu (also known as lamin) remains one of the most thoroughly studied. GHK‐Cu functions as both a signaling and carrier peptide, contributing to extracellular matrix remodeling and being released at sites of tissue injury or inflammation. At these sites, it stimulates the synthesis of collagen, elastin, proteoglycans, and glycosaminoglycans while demonstrating significant anti‐inflammatory and antioxidant properties [6–13].
Currently, GHK‐Cu holds a prominent position in cosmetic and dermatologic medicine due to its broad therapeutic profile. Its documented benefits include anti‐aging and anti‐wrinkle effects, post‐ultraviolet repair, enhancement of skin hydration, and stimulation of hair growth, supporting its continued integration into both clinical and cosmeceutical applications [7–13].
1.3 | Why GHK Is Chelated to Copper
GHK (glycyl‐L‐histidyl‐L‐lysine) is an endogenous tripeptide originally identified in human plasma, serum, saliva, and urine, where it was observed to stimulate cellular growth and tissue regeneration [2, 3]. A defining biochemical feature of this peptide is its high affinity for divalent copper ions (Cu²⁺), resulting in the formation of the biologically active chelated complex GHK‐Cu [2, 3].
Physiologically, circulating levels of GHK peak in early adulthood, with average plasma concentrations of approximately 200 ng/mL at 20 years of age. These levels progressively decline with aging, reaching roughly 80 ng/mL by 60 years of age—a reduction that may correlate with diminished regenerative capacity over time [2, 3, 9]. Experimental and clinical investigations consistently demonstrate that GHK‐Cu plays a critical role in maintaining skin and connective‐tissue integrity by promoting cellular proliferation, collagen synthesis, and repair‐related signaling pathways [7–13].
1.4 | GHK‐Cu in Aesthetic Medicine
For nearly 40 years, GHK‐Cu has been recognized for its capacity to stimulate tissue remodeling and accelerate wound repair processes [4, 8–10]. Copper itself is an essential trace element required for enzymatic reactions involved in collagen cross‐linking and elastin formation. In this context, GHK functions as a physiologic copper carrier, facilitating targeted copper delivery to tissues undergoing repair and regeneration [1, 5, 10, 12].
Seminal work by Siméon and Wegrowski demonstrated that GHK‐Cu enhances the biosynthesis of glycosaminoglycans (GAGs), increases chondroitin sulfate accumulation, and up‐regulates type I collagen production. Collectively, these effects translate into measurable improvements in skin elasticity, clarity, and surface smoothness [6, 14]. These mechanistic findings underpin the longstanding inclusion of GHK‐Cu in anti‐aging and reparative skincare formulations [1, 4, 7, 8].
Notably, synergistic effects have been observed when GHK‐Cu is combined with hyaluronic acid (HA). In both in vitro and ex vivo models, this combination significantly amplifies collagen expression, with collagen IV production increasing by as much as 25‐fold in cell cultures and nearly twofold in human skin samples. The most pronounced effects were observed at a 1:9 ratio of GHK‐Cu to low‐molecular‐weight HA [5, 15]. This synergism appears to strengthen the dermal‐epidermal junction (DEJ), contributing to enhanced skin firmness and mechanical resilience [4–6, 15].
Multiple placebo‐controlled clinical trials and laboratory studies further validate the broad regenerative properties of GHK‐Cu. Documented outcomes include increased keratinocyte proliferation, improvements in skin firmness and elasticity, enhanced barrier function, and reductions in rhytides, hyperpigmentation, and ultraviolet‐induced photodamage [11]. Notably, topical GHK‐Cu has demonstrated superior stimulation of procollagen synthesis compared with established agents such as vitamin C, tretinoin, and melatonin [11].
In comparative clinical evaluations, GHK‐Cu increased collagen deposition in 70% of study participants, outperforming vitamin C (50%) and retinoic acid (40%) following 1 month of daily application [7]. Similarly, Leyden et al. reported that 12 weeks of treatment with GHK‐Cu‐containing formulations resulted in significant improvements in skin density, thickness, elasticity, and hydration, yielding visibly smoother and more youthful‐appearing skin [4]. These findings were corroborated by a separate 12‐week study involving 67 women, which demonstrated that twice‐daily application of GHK‐Cu cream significantly increased epidermal and dermal thickness and stimulated keratinocyte proliferation, corresponding with observable improvements in skin texture and radiance [7].
1.5 | GHK‐Cu and Hair Growth
The copper tripeptide GHK‐Cu (L‐alanyl‐L‐histidyl‐L‐lysine–Cu²⁺) has demonstrated strong hair‐regenerative effects in human experimental models. Ex vivo studies indicate that GHK‐Cu significantly promotes human hair‐follicle elongation at ultra‐low concentrations (10⁻¹² to 10⁻⁹ M), reflecting high biological potency [21]. In cultured dermal papilla cells (DPCs), which serve as central regulators of the hair‐growth cycle, GHK‐Cu enhances both cellular proliferation and metabolic activity, thereby strengthening signaling to the surrounding follicular matrix [21].
In addition to its proliferative effects, GHK‐Cu favorably alters apoptotic signaling within DPCs. Exposure to GHK‐Cu increases expression of the anti‐apoptotic protein Bcl‐2 while decreasing levels of the pro‐apoptotic marker Bax. Concurrently, cleaved caspase‐3 and PARP fragmentation are reduced by 42.7% and 77.5%, respectively [21]. This coordinated suppression of apoptosis supports healthier and more resilient DPCs capable of sustaining active anagen‐phase hair growth.
Overall, GHK‐Cu supports hair regeneration by stimulating DPC proliferation, promoting follicular elongation, and protecting hair‐regulatory cells from apoptosis—resulting in stronger, longer‐growing hair follicles [21]. In clinical and translational studies, GHK‐Cu has also been shown to enhance hair growth by supporting follicular enlargement, improving scalp collagen quality, and increasing hair‐shaft strength, with outcomes comparable to those observed with topical minoxidil.
