GHK-Cu

1. Studied for

   GHK-Cu: randomized human trial, topical gel, diabetic neuropathic ulcers

   In a multicenter, randomized, evaluator-blinded, placebo-controlled clinical trial, a topical GHK-Cu gel was applied to diabetic neuropathic plantar ulcers on top of an aggressive standardized wound-care protocol: sharp debridement at study entry, daily application, pressure-relieving footwear and education on diabetes control. The published report gives a median area-percentage closure of 98.5% in the GHK-Cu gel group versus 60.8% in the vehicle group, a higher proportion of people healing 98% or better, and a closure rate described as roughly 3 times faster than vehicle plus standard care. In the larger ulcers at study entry, the enhancement was more pronounced: a median of 89.2% versus a negative value for vehicle, meaning the larger ulcers given only vehicle tended to grow rather than close over the study period. Ulcer infection was also less frequent with immediate post-debridement use. This is a single 1994 trial of a single named topical gel formulation on open diabetic plantar ulcers under an aggressive wound-care protocol; it describes that gel in that population and says nothing about any other format or about a lyophilized research compound outside that formulation. HUMAN randomized, evaluator-blinded, placebo-controlled human trial, topical gel formulation, diabetic neuropathic plantar ulcers Preclinical strong Convergent results from more than one independent laboratory across more than one experimental system, or a single well-designed randomized human trial. Still the ceiling of what this page shows: 'strong' here never means the compound is an approved or recommended treatment. Open for the full finding and the paper it came from.

   In the literature

   GHK-Cu: randomized human trial, topical gel, diabetic neuropathic ulcers

   In a multicenter, randomized, evaluator-blinded, placebo-controlled clinical trial, a topical GHK-Cu gel was applied to diabetic neuropathic plantar ulcers on top of an aggressive standardized wound-care protocol: sharp debridement at study entry, daily application, pressure-relieving footwear and education on diabetes control. The published report gives a median area-percentage closure of 98.5% in the GHK-Cu gel group versus 60.8% in the vehicle group, a higher proportion of people healing 98% or better, and a closure rate described as roughly 3 times faster than vehicle plus standard care. In the larger ulcers at study entry, the enhancement was more pronounced: a median of 89.2% versus a negative value for vehicle, meaning the larger ulcers given only vehicle tended to grow rather than close over the study period. Ulcer infection was also less frequent with immediate post-debridement use. This is a single 1994 trial of a single named topical gel formulation on open diabetic plantar ulcers under an aggressive wound-care protocol; it describes that gel in that population and says nothing about any other format or about a lyophilized research compound outside that formulation.^{References 1}

   Modelrandomized, evaluator-blinded, placebo-controlled human trial, topical gel formulation, diabetic neuropathic plantar ulcers

   Confidence: strong

   Convergent results from more than one independent laboratory across more than one experimental system, or a single well-designed randomized human trial. Still the ceiling of what this page shows: 'strong' here never means the compound is an approved or recommended treatment.

   Source

   Mulder GD, Patt LM, Sanders L, Rosenstock J, Altman MI, Hanley ME, Duncan GW. Enhanced healing of ulcers in patients with diabetes by topical treatment with glycyl-L-histidyl-L-lysine copper. Wound Repair Regen. 1994;2(4):259-269. DOI 10.1046/j.1524-475X.1994.20406.x.

   Source

   How this citation was checked

   The Crossref API was queried live for this DOI and returned this exact title, these 7 authors in this order, Wound Repair and Regeneration, 1994, volume 2, issue 4, pages 259 to 269, plus the full abstract, read directly: it confirms the multicenter randomized evaluator-blinded placebo-controlled design, the standardized wound-care protocol, the 98.5% versus 60.8% median closure figures, the roughly-3-times-faster language, the 89.2%-versus-negative result in larger ulcers, and the lower infection incidence with immediate post-debridement use. A PubMed search for this paper returned no hit, confirming it is not MEDLINE-indexed, so the Crossref-hosted abstract is the load-bearing verification and no PMID is asserted for this reference.

2. Studied for

   GHK-Cu: wound-repair investigation across species

   A 2015 peer-reviewed review reports that GHK-Cu accelerated wound healing and increased blood vessel formation and antioxidant enzyme levels in rabbits, induced systemic wound healing in rats, mice and pigs, and improved the healing of diabetic and ischemic wounds in rats while lowering an inflammatory marker (TNF-alpha) and stimulating collagen synthesis in that same rat tissue. These are animal findings, synthesized inside a review rather than independently re-resolved to their individual original reports in this pass; no human outcome is implied by any of them. rabbit, rat, mouse and pig models, as synthesized in a peer-reviewed review Preclinical moderate A well-described result with several independent outcome measures, but from a single laboratory, a single research program, or a review's own synthesis of earlier work. Open for the full finding and the paper it came from.

   In the literature

   GHK-Cu: wound-repair investigation across species

   A 2015 peer-reviewed review reports that GHK-Cu accelerated wound healing and increased blood vessel formation and antioxidant enzyme levels in rabbits, induced systemic wound healing in rats, mice and pigs, and improved the healing of diabetic and ischemic wounds in rats while lowering an inflammatory marker (TNF-alpha) and stimulating collagen synthesis in that same rat tissue. These are animal findings, synthesized inside a review rather than independently re-resolved to their individual original reports in this pass; no human outcome is implied by any of them.^{References 2}

   Modelrabbit, rat, mouse and pig models, as synthesized in a peer-reviewed review

   Confidence: moderate

   A well-described result with several independent outcome measures, but from a single laboratory, a single research program, or a review's own synthesis of earlier work.

   Source

   Pickart L, Vasquez-Soltero JM, Margolina A. GHK Peptide as a Natural Modulator of Multiple Cellular Pathways in Skin Regeneration. Biomed Res Int. 2015;2015:648108. DOI 10.1155/2015/648108. PMC4508379.

   Source

   How this citation was checked

   The Crossref API was queried live for this DOI and returned this exact title, these 3 authors (Loren Pickart, Jessica Michelle Vasquez-Soltero, Anna Margolina) in this order, BioMed Research International, 2015, volume 2015, article 648108. The full text was fetched live from PMC4508379 and read directly: it states, of the sentence quoted in _verbatim_quotes, that GHK-Cu 'also induced systemic wound healing in rats, mice, and pigs' and 'improved the healing of diabetic and ischemic wounds in rats, decreasing the level of TNF-alpha and stimulating collagen synthesis.' The review does not name which primary papers underlie each species result in the sentence quoted, and those primary reports were not separately traced in this pass, which is why this area stays at moderate rather than strong despite the multi-species breadth. No PMID is given in the source material for this review; it is cited by DOI and PMC ID.

3. Studied for

   GHK-Cu: independent laboratory replication of matrix remodeling (MMP-2, TIMPs, proteoglycans)

   A French laboratory independently studied GHK-Cu's effects on the extracellular matrix in 2 related reports. In cultured dermal fibroblasts, GHK-Cu increased matrix metalloproteinase-2 (MMP-2) protein and mRNA levels and increased secretion of the tissue inhibitors of metalloproteinases TIMP-1 and TIMP-2; the authors state that GHK-Cu is an activator of both connective-tissue production and of extracellular-matrix remodeling, not unidirectional collagen building. A key form-specific result from this same report: the MMP-2 increase was reproduced by copper ions but not by the tripeptide GHK alone, meaning this particular effect depended on the copper, not just the peptide backbone. In a second report from the same laboratory, repeated GHK-Cu use in a rat experimental wound-chamber model increased wound-tissue dry weight, total protein, type I collagen and glycosaminoglycan content, and increased chondroitin sulfate and dermatan sulfate accumulation over controls; it also raised decorin gene expression in both the wound chamber and in separate rat skin-cell cultures, while a second small proteoglycan, biglycan, responded differently in tissue than in culture, read by the authors as evidence that different proteoglycans are regulated differently across the wound-repair process rather than uniformly. Both reports test GHK-Cu, the copper complex, except for the copper-dependence comparison itself. IN VITRO cultured human and rat dermal fibroblasts (in vitro), plus a rat experimental wound-chamber model (in vivo) for the proteoglycan report Preclinical moderate A well-described result with several independent outcome measures, but from a single laboratory, a single research program, or a review's own synthesis of earlier work. Open for the full finding and the paper it came from.

   In the literature

   GHK-Cu: independent laboratory replication of matrix remodeling (MMP-2, TIMPs, proteoglycans)

   A French laboratory independently studied GHK-Cu's effects on the extracellular matrix in 2 related reports. In cultured dermal fibroblasts, GHK-Cu increased matrix metalloproteinase-2 (MMP-2) protein and mRNA levels and increased secretion of the tissue inhibitors of metalloproteinases TIMP-1 and TIMP-2; the authors state that GHK-Cu is an activator of both connective-tissue production and of extracellular-matrix remodeling, not unidirectional collagen building. A key form-specific result from this same report: the MMP-2 increase was reproduced by copper ions but not by the tripeptide GHK alone, meaning this particular effect depended on the copper, not just the peptide backbone. In a second report from the same laboratory, repeated GHK-Cu use in a rat experimental wound-chamber model increased wound-tissue dry weight, total protein, type I collagen and glycosaminoglycan content, and increased chondroitin sulfate and dermatan sulfate accumulation over controls; it also raised decorin gene expression in both the wound chamber and in separate rat skin-cell cultures, while a second small proteoglycan, biglycan, responded differently in tissue than in culture, read by the authors as evidence that different proteoglycans are regulated differently across the wound-repair process rather than uniformly. Both reports test GHK-Cu, the copper complex, except for the copper-dependence comparison itself.^{References 3, 4}

   Modelcultured human and rat dermal fibroblasts (in vitro), plus a rat experimental wound-chamber model (in vivo) for the proteoglycan report

   Confidence: moderate

   A well-described result with several independent outcome measures, but from a single laboratory, a single research program, or a review's own synthesis of earlier work.

   Source

   Simeon A, Emonard H, Hornebeck W, Maquart FX. The tripeptide-copper complex glycyl-L-histidyl-L-lysine-Cu2+ stimulates matrix metalloproteinase-2 expression by fibroblast cultures. Life Sci. 2000;67(18):2257-2265. PMID 11045606. Simeon A, Wegrowski Y, Bontemps Y, Maquart FX. Expression of glycosaminoglycans and small proteoglycans in wounds: modulation by the tripeptide-copper complex glycyl-L-histidyl-L-lysine-Cu(2+). J Invest Dermatol. 2000;115(6):962-968. PMID 11121126.

   PubMed 11045606 PubMed 11121126

   How this citation was checked

   NCBI E-utilities esummary and efetch were queried live for both PMIDs. PMID 11045606 returned Simeon A, Emonard H, Hornebeck W, Maquart FX, Life Sciences, 2000, volume 67, issue 18, pages 2257 to 2265, and the abstract confirms verbatim that the MMP-2 effect 'was reproduced by copper ions but not by the tripeptide GHK alone' and that GHK-Cu increased secretion of TIMP-1 and TIMP-2. PMID 11121126 returned Simeon A, Wegrowski Y, Bontemps Y, Maquart FX, Journal of Investigative Dermatology, 2000, volume 115, issue 6, pages 962 to 968, and its abstract confirms the rat wound-chamber model, the dry-weight and total-protein increases, the collagen and glycosaminoglycan increases, the chondroitin and dermatan sulfate accumulation, the decorin increase in both systems, and that biglycan responded differently across them. Neither paper carries the 2015 review's lead author, and the laboratory (Reims, France) is described in _source as historically linked to that author through a separate 1988 founding paper rather than fully independent; confidence is held at moderate on that basis, alongside the absence of human data in either report. No DOI was located for either PMID in this pass.

4. Studied for

   GHK-Cu: protective effects in animal models of oxidative and inflammatory organ injury (2020 to 2025)

   A cluster of studies published from 2020 to 2025, independent of the 2015 review, tested systemically given GHK-Cu in mouse models of organ injury driven by oxidative stress and inflammation. In bleomycin-induced pulmonary fibrosis, GHK-Cu reduced inflammatory cytokines and collagen deposition in lung tissue and reduced markers of epithelial-to-mesenchymal transition. In cigarette-smoke-induced pulmonary emphysema, GHK-Cu lessened the emphysematous tissue changes, partially reversed an MMP-9/TIMP-1 imbalance in lung tissue, and reduced inflammatory cytokines in lung-lavage fluid, with a matching antioxidant effect shown separately in cultured human lung-lining cells. In a silicosis model, GHK-Cu was reported to reduce lung inflammation and fibrosis, linked by the authors to the antioxidant enzyme peroxiredoxin 6. In a cigarette-smoke skeletal-muscle-dysfunction model, GHK-Cu improved muscle function measures through a pathway the authors tie to the protein sirtuin 1; the same report includes a small human observational comparison, endogenous plasma GHK measured in 9 people with chronic lung disease against 11 age-matched healthy people, a correlational comparison of naturally occurring peptide levels, not a study of given GHK-Cu, and is reported here as exactly that. A related 2025 report from a partly overlapping author network extended a similar oxidative-stress and inflammation-reduction pattern to a mouse model of chemically induced colitis, reporting reduced disease-activity scores, preserved gut-lining cells, reduced inflammatory cytokines and improved gut-barrier protein expression. Four of these 5 reports share overlapping authorship centered on 2 institutions, so this is convergent evidence across several organ-injury models from a largely contiguous research program, not independent replication by unconnected laboratories. All animal work here used GHK-Cu, the copper complex; none of it is human interventional data. mouse models of bleomycin-induced pulmonary fibrosis, cigarette-smoke-induced emphysema, silica-induced silicosis, cigarette-smoke skeletal muscle dysfunction, and colitis, plus cultured human lung-epithelial cells and a small human observational plasma comparison Preclinical moderate A well-described result with several independent outcome measures, but from a single laboratory, a single research program, or a review's own synthesis of earlier work. Open for the full finding and the paper it came from.

   In the literature

   GHK-Cu: protective effects in animal models of oxidative and inflammatory organ injury (2020 to 2025)

   A cluster of studies published from 2020 to 2025, independent of the 2015 review, tested systemically given GHK-Cu in mouse models of organ injury driven by oxidative stress and inflammation. In bleomycin-induced pulmonary fibrosis, GHK-Cu reduced inflammatory cytokines and collagen deposition in lung tissue and reduced markers of epithelial-to-mesenchymal transition. In cigarette-smoke-induced pulmonary emphysema, GHK-Cu lessened the emphysematous tissue changes, partially reversed an MMP-9/TIMP-1 imbalance in lung tissue, and reduced inflammatory cytokines in lung-lavage fluid, with a matching antioxidant effect shown separately in cultured human lung-lining cells. In a silicosis model, GHK-Cu was reported to reduce lung inflammation and fibrosis, linked by the authors to the antioxidant enzyme peroxiredoxin 6. In a cigarette-smoke skeletal-muscle-dysfunction model, GHK-Cu improved muscle function measures through a pathway the authors tie to the protein sirtuin 1; the same report includes a small human observational comparison, endogenous plasma GHK measured in 9 people with chronic lung disease against 11 age-matched healthy people, a correlational comparison of naturally occurring peptide levels, not a study of given GHK-Cu, and is reported here as exactly that. A related 2025 report from a partly overlapping author network extended a similar oxidative-stress and inflammation-reduction pattern to a mouse model of chemically induced colitis, reporting reduced disease-activity scores, preserved gut-lining cells, reduced inflammatory cytokines and improved gut-barrier protein expression. Four of these 5 reports share overlapping authorship centered on 2 institutions, so this is convergent evidence across several organ-injury models from a largely contiguous research program, not independent replication by unconnected laboratories. All animal work here used GHK-Cu, the copper complex; none of it is human interventional data.^{References 5, 6, 7, 8, 9}

   Modelmouse models of bleomycin-induced pulmonary fibrosis, cigarette-smoke-induced emphysema, silica-induced silicosis, cigarette-smoke skeletal muscle dysfunction, and colitis, plus cultured human lung-epithelial cells and a small human observational plasma comparison

   Confidence: moderate

   A well-described result with several independent outcome measures, but from a single laboratory, a single research program, or a review's own synthesis of earlier work.

   Source

   Ma WH, Li M, Ma HF, Li W, Liu L, Yin Y, Zhou XM, Hou G. Protective effects of GHK-Cu in bleomycin-induced pulmonary fibrosis via anti-oxidative stress and anti-inflammation pathways. Life Sci. 2020;241:117139. PMID 31809714. Zhang Q, Yan L, Lu J, Zhou X. Glycyl-L-histidyl-L-lysine-Cu(2+) attenuates cigarette smoke-induced pulmonary emphysema and inflammation by reducing oxidative stress pathway. Front Mol Biosci. 2022;9:925700. PMID 35936787. Deng M, Zhang Q, Yan L, Bian Y, Li R, Gao J, Wang Y, Miao J, Li J, Zhou X, Hou G. Glycyl-l-histidyl-l-lysine-Cu(2+) rescues cigarette smoking-induced skeletal muscle dysfunction via a sirtuin 1-dependent pathway. J Cachexia Sarcopenia Muscle. 2023;14(3):1365-1380. PMID 36905132. Bian Y, Deng M, Liu J, Li J, Zhang Q, Wang Z, Liao L, Miao J, Li R, Zhou X, Hou G. The glycyl-l-histidyl-l-lysine-Cu(2+) tripeptide complex attenuates lung inflammation and fibrosis in silicosis by targeting peroxiredoxin 6. Redox Biol. 2024;75:103237. PMID 38879894. Mao S, Huang J, Li J, Sun F, Zhang Q, Cheng Q, Zeng W, Lei D, Wang S, Yao J. Exploring the beneficial effects of GHK-Cu on an experimental model of colitis and the underlying mechanisms. Front Pharmacol. 2025;16:1551843. PMID 40672369.

   PubMed 31809714 PubMed 35936787 PubMed 36905132 PubMed 38879894 PubMed 40672369

   How this citation was checked

   NCBI E-utilities esummary and efetch were queried live for all 5 PMIDs; author order, journal, year, volume, issue and pages matched what is written above in every case. Abstracts were read in full and confirm the bleomycin, emphysema, silicosis, muscle and colitis models and outcomes described. Author overlap was checked directly: Zhou X appears on 4 of the 5 papers and Hou G on 3 of the 5. None of the source abstracts describes a human treatment outcome for given GHK-Cu; the muscle report's human arm measures only endogenous, unexposed plasma levels. No DOI was located for any of the 5 PMIDs in this pass.

5. Studied for

   GHK-Cu: extracellular-matrix and collagen turnover, low-nanomolar in vitro

   In cell-culture work summarized in the 2015 review, GHK-Cu, at very low, non-toxic concentrations, stimulated both synthesis and breakdown of collagen and glycosaminoglycans, stimulated dermatan sulfate, chondroitin sulfate and the small proteoglycan decorin, and modulated the activity of metalloproteinases and their inhibitors TIMP-1 and TIMP-2. The review's own wording is that it affects 'both synthesis and breakdown,' meaning turnover and remodeling, not unidirectional collagen building. This entry is the review's own narrative summary of earlier work rather than a separately re-resolved original report. IN VITRO in vitro (cultured cells), as summarized in a peer-reviewed review Preclinical preliminary A single study, an early mechanistic observation, or a result whose interpretation is the authors' own inference. Open for the full finding and the paper it came from.

   In the literature

   GHK-Cu: extracellular-matrix and collagen turnover, low-nanomolar in vitro

   In cell-culture work summarized in the 2015 review, GHK-Cu, at very low, non-toxic concentrations, stimulated both synthesis and breakdown of collagen and glycosaminoglycans, stimulated dermatan sulfate, chondroitin sulfate and the small proteoglycan decorin, and modulated the activity of metalloproteinases and their inhibitors TIMP-1 and TIMP-2. The review's own wording is that it affects 'both synthesis and breakdown,' meaning turnover and remodeling, not unidirectional collagen building. This entry is the review's own narrative summary of earlier work rather than a separately re-resolved original report.^{References 2}

   Modelin vitro (cultured cells), as summarized in a peer-reviewed review

   Confidence: preliminary

   A single study, an early mechanistic observation, or a result whose interpretation is the authors' own inference.

   Source

   Pickart L, Vasquez-Soltero JM, Margolina A. GHK Peptide as a Natural Modulator of Multiple Cellular Pathways in Skin Regeneration. Biomed Res Int. 2015;2015:648108. DOI 10.1155/2015/648108. PMC4508379.

   Source

   How this citation was checked

   Same Crossref DOI resolution as the wound-repair entry above. PMC4508379 was fetched live and read directly; it states that GHK-Cu 'stimulated both synthesis and breakdown of collagen and glycosaminoglycans' and, in an adjoining sentence, that it stimulated collagen, dermatan sulfate, chondroitin sulfate and decorin, and modulated metalloproteinase and TIMP activity. Rated preliminary because it is a review's narrative synthesis of the originating investigator's own earlier work, not an independently traced primary study; compare the moderate-rated independent replication of a related but distinct effect elsewhere in this dossier.

6. Studied for

   GHK-Cu: anti-inflammatory cytokine modulation in dermal fibroblasts

   An independent Polish laboratory reported that GHK-Cu, its copper-free precursor GHK, the related tripeptide Gly-Gly-His and its copper complex, and copper chloride itself all decreased TNF-alpha-driven secretion of the pro-inflammatory cytokine IL-6 in cultured normal human dermal fibroblasts, while a comparison ingredient had no effect. The authors propose, as their own interpretation, that these copper-peptides could be explored as topical alternatives to corticosteroids or non-steroidal anti-inflammatory drugs for skin surface use; that is the study authors' own framing of a possible future direction, not a demonstrated outcome, and no drug-replacement claim is made in this dossier. IN VITRO in vitro, cultured normal human dermal fibroblasts, IL-6 measured by ELISA Preclinical preliminary A single study, an early mechanistic observation, or a result whose interpretation is the authors' own inference. Open for the full finding and the paper it came from.

   In the literature

   GHK-Cu: anti-inflammatory cytokine modulation in dermal fibroblasts

   An independent Polish laboratory reported that GHK-Cu, its copper-free precursor GHK, the related tripeptide Gly-Gly-His and its copper complex, and copper chloride itself all decreased TNF-alpha-driven secretion of the pro-inflammatory cytokine IL-6 in cultured normal human dermal fibroblasts, while a comparison ingredient had no effect. The authors propose, as their own interpretation, that these copper-peptides could be explored as topical alternatives to corticosteroids or non-steroidal anti-inflammatory drugs for skin surface use; that is the study authors' own framing of a possible future direction, not a demonstrated outcome, and no drug-replacement claim is made in this dossier.^{References 10}

   Modelin vitro, cultured normal human dermal fibroblasts, IL-6 measured by ELISA

   Confidence: preliminary

   A single study, an early mechanistic observation, or a result whose interpretation is the authors' own inference.

   Source

   Gruchlik A, Jurzak M, Chodurek E, Dzierzewicz Z. Effect of Gly-Gly-His, Gly-His-Lys and their copper complexes on TNF-alpha-dependent IL-6 secretion in normal human dermal fibroblasts. Acta Pol Pharm. 2012;69(6):1303-1306. PMID 23285694.

   PubMed 23285694

   How this citation was checked

   This citation was located inside the 2015 review's own reference list and then independently re-resolved to PubMed directly rather than carried over secondhand. NCBI E-utilities esummary and efetch were queried live and returned Gruchlik A, Jurzak M, Chodurek E, Dzierzewicz Z, Acta Poloniae Pharmaceutica, 2012, volume 69, issue 6, pages 1303 to 1306, author affiliation Medical University of Silesia, Sosnowiec, Poland, confirming a laboratory with no connection to the review's authors. The abstract confirms the decreased IL-6 secretion result and the corticosteroid-alternative framing as the authors' own proposal. Rated preliminary because it is a single in vitro study with no replication located. No DOI was located for this PMID in this pass.

7. Studied for

   GHK-Cu and copper-free GHK: keratinocyte proliferation and epidermal stem-cell markers

   2 separate lines of evidence, testing 2 different forms of the molecule, both point toward increased keratinocyte proliferation and proliferation-marker expression. First, the 2015 review states that GHK-Cu, at low concentrations, increased expression of epidermal stem-cell markers such as integrins and p63 in basal keratinocytes in skin-equivalent models, which the cited authors interpret as increased proliferative potential; this is the review's own summary, not independently re-resolved to its underlying original report in this pass. Second, and independently, a Korean laboratory tested copper-free GHK specifically and reported that it increased proliferation of cultured normal human keratinocytes, increased integrin staining and proliferation-marker-positive cell counts in skin-equivalent models, and increased integrin expression by Western blot. The authors' own conclusion is that copper-free GHK produced effects similar to what had been reported for GHK-Cu in that system, which they read as support for using the copper-free form to obtain effects otherwise associated with the copper complex; that is the cited authors' own inference, not a conclusion this dossier repeats as its own claim. IN VITRO in vitro, cultured human keratinocytes and skin-equivalent (organotypic) models Preclinical preliminary A single study, an early mechanistic observation, or a result whose interpretation is the authors' own inference. Open for the full finding and the paper it came from.

   In the literature

   GHK-Cu and copper-free GHK: keratinocyte proliferation and epidermal stem-cell markers

   2 separate lines of evidence, testing 2 different forms of the molecule, both point toward increased keratinocyte proliferation and proliferation-marker expression. First, the 2015 review states that GHK-Cu, at low concentrations, increased expression of epidermal stem-cell markers such as integrins and p63 in basal keratinocytes in skin-equivalent models, which the cited authors interpret as increased proliferative potential; this is the review's own summary, not independently re-resolved to its underlying original report in this pass. Second, and independently, a Korean laboratory tested copper-free GHK specifically and reported that it increased proliferation of cultured normal human keratinocytes, increased integrin staining and proliferation-marker-positive cell counts in skin-equivalent models, and increased integrin expression by Western blot. The authors' own conclusion is that copper-free GHK produced effects similar to what had been reported for GHK-Cu in that system, which they read as support for using the copper-free form to obtain effects otherwise associated with the copper complex; that is the cited authors' own inference, not a conclusion this dossier repeats as its own claim.^{References 2, 11}

   Modelin vitro, cultured human keratinocytes and skin-equivalent (organotypic) models

   Confidence: preliminary

   A single study, an early mechanistic observation, or a result whose interpretation is the authors' own inference.

   Source

   Pickart L, Vasquez-Soltero JM, Margolina A. Biomed Res Int. 2015;2015:648108. DOI 10.1155/2015/648108. PMC4508379 (GHK-Cu figure). Choi HR, Kang YA, Ryoo SJ, Shin JW, Na JI, Huh CH, Park KC. Stem cell recovering effect of copper-free GHK in skin. J Pept Sci. 2012;18(11):685-690. PMID 23019153 (copper-free GHK study).

   Source PubMed 23019153

   How this citation was checked

   The review DOI was re-resolved via Crossref as elsewhere in this dossier, and PMC4508379 was fetched live and read directly; its stem-cell section states that GHK-Cu, at low concentrations, increased expression of epidermal stem-cell markers in basal keratinocytes in dermal skin equivalents. PMID 23019153 was independently re-resolved via NCBI esummary and efetch, returning Choi HR and 6 co-authors, Seoul National University Bundang Hospital, Korea, Journal of Peptide Science, 2012, volume 18, issue 11, pages 685 to 690, with no author overlap with the review. The abstract confirms the keratinocyte proliferation result, the integrin and marker findings, and the authors' own statement that copper-free GHK showed similar effects to copper-GHK. Rated preliminary: the review portion is secondhand and the independent portion is a single in vitro study testing the copper-free form. No DOI was located for the Choi PMID in this pass.

8. Studied for

   GHK-Cu: topical cosmetic-study results reported secondhand in the review

   The 2015 review describes 2 separate topical human studies that should not be merged. First, a placebo-controlled study in which creams were applied to the thigh for 1 month measured collagen increases in 70% of the women who used a GHK-Cu cream, versus 50% for a vitamin C cream and 40% for retinoic acid. Second, a separate 12-week facial-cream study in 71 women with mild to advanced photoaging assessed visible skin parameters (laxity, clarity, fine lines, wrinkle depth, density and thickness) and did not measure collagen; the review attributes this to a conference presentation rather than a peer-reviewed paper. Both are reported here strictly as described inside the review; this pass re-resolved the review itself, not these 2 underlying original reports, and both are finished cosmetic cream products, not the compound alone, which is the boundary this dossier holds throughout. human topical cosmetic-cream studies, described secondhand within a peer-reviewed review Preclinical preliminary A single study, an early mechanistic observation, or a result whose interpretation is the authors' own inference. Open for the full finding and the paper it came from.

   In the literature

   GHK-Cu: topical cosmetic-study results reported secondhand in the review

   The 2015 review describes 2 separate topical human studies that should not be merged. First, a placebo-controlled study in which creams were applied to the thigh for 1 month measured collagen increases in 70% of the women who used a GHK-Cu cream, versus 50% for a vitamin C cream and 40% for retinoic acid. Second, a separate 12-week facial-cream study in 71 women with mild to advanced photoaging assessed visible skin parameters (laxity, clarity, fine lines, wrinkle depth, density and thickness) and did not measure collagen; the review attributes this to a conference presentation rather than a peer-reviewed paper. Both are reported here strictly as described inside the review; this pass re-resolved the review itself, not these 2 underlying original reports, and both are finished cosmetic cream products, not the compound alone, which is the boundary this dossier holds throughout.^{References 2}

   Modelhuman topical cosmetic-cream studies, described secondhand within a peer-reviewed review

   Confidence: preliminary

   A single study, an early mechanistic observation, or a result whose interpretation is the authors' own inference.

   Source

   Pickart L, Vasquez-Soltero JM, Margolina A. Biomed Res Int. 2015;2015:648108. DOI 10.1155/2015/648108. PMC4508379.

   Source

   How this citation was checked

   Same Crossref DOI resolution as elsewhere in this dossier. PMC4508379 was fetched live and read directly; it attributes the collagen-increase figures to Abdulghani et al. 1998, a journal article, and the facial-cream study to a Leyden et al. American Academy of Dermatology meeting presentation from 2002, a named conference presentation rather than a journal article, confirmed by reading the review's own reference-list entry types. Neither underlying original report was independently resolved in this pass, which keeps this entry at preliminary.

9. Studied for

   GHK: gene-expression database analysis

   Using the Broad Institute's Connectivity Map, a computational gene-expression database tool, GHK was reported to increase expression of DNA-repair genes, with 47 genes stimulated and 5 suppressed at a threshold of at least a 50% change. The review separately makes a much broader claim about GHK regulating thousands of genes; on direct reading of the review in this pass, no underlying study or methodology is supplied for that broader figure anywhere in the text, so it is not stated as a finding here (see cannot_support). The review's framing that this represents resetting a cell toward a healthier state is the authors' own interpretive language, not a finding, and is not repeated here. computational transcriptomic database analysis (Connectivity Map); no cell type specified in the review Preclinical preliminary A single study, an early mechanistic observation, or a result whose interpretation is the authors' own inference. Open for the full finding and the paper it came from.

   In the literature

   GHK: gene-expression database analysis

   Using the Broad Institute's Connectivity Map, a computational gene-expression database tool, GHK was reported to increase expression of DNA-repair genes, with 47 genes stimulated and 5 suppressed at a threshold of at least a 50% change. The review separately makes a much broader claim about GHK regulating thousands of genes; on direct reading of the review in this pass, no underlying study or methodology is supplied for that broader figure anywhere in the text, so it is not stated as a finding here (see cannot_support). The review's framing that this represents resetting a cell toward a healthier state is the authors' own interpretive language, not a finding, and is not repeated here.^{References 2}

   Modelcomputational transcriptomic database analysis (Connectivity Map); no cell type specified in the review

   Confidence: preliminary

   A single study, an early mechanistic observation, or a result whose interpretation is the authors' own inference.

   Source

   Pickart L, Vasquez-Soltero JM, Margolina A. Biomed Res Int. 2015;2015:648108. DOI 10.1155/2015/648108. PMC4508379.

   Source

   How this citation was checked

   Same Crossref DOI resolution as elsewhere in this dossier. PMC4508379 was fetched live and read directly; it states that Connectivity Map analysis found GHK significantly increased expression of DNA repair genes, with 47 genes stimulated and 5 suppressed at a threshold of at least a 50% change. A targeted re-read specifically for the broader gene-count figure found no supporting methodology and no named cell type for the Connectivity Map analysis anywhere in the text, both stated here as coverage limits.

10. Studied for

    GHK: antioxidant characterization

    The review characterizes GHK as able to quench some toxins generated during lipid peroxidation, describing it as an efficient antioxidant, and states it helps reduce the level of free ionic copper, which the authors relate to limiting oxidative damage. This is biochemical characterization of the molecule's chemistry, not a demonstrated outcome in a cell, tissue or organism. biochemical characterization as described in a review Preclinical preliminary A single study, an early mechanistic observation, or a result whose interpretation is the authors' own inference. Open for the full finding and the paper it came from.

    In the literature

    GHK: antioxidant characterization

    The review characterizes GHK as able to quench some toxins generated during lipid peroxidation, describing it as an efficient antioxidant, and states it helps reduce the level of free ionic copper, which the authors relate to limiting oxidative damage. This is biochemical characterization of the molecule's chemistry, not a demonstrated outcome in a cell, tissue or organism.^{References 2}

    Modelbiochemical characterization as described in a review

    Confidence: preliminary

    A single study, an early mechanistic observation, or a result whose interpretation is the authors' own inference.

    Source

    Pickart L, Vasquez-Soltero JM, Margolina A. Biomed Res Int. 2015;2015:648108. DOI 10.1155/2015/648108. PMC4508379.

    Source

    How this citation was checked

    Same Crossref DOI resolution as elsewhere in this dossier. PMC4508379 was fetched live and read directly; it states that GHK can quench toxins generated during lipid peroxidation, that this makes it an efficient antioxidant, and that it helps reduce free ionic copper, limiting the possibility of oxidative damage.

11. Studied for

    GHK-Cu: transgenic mouse model of Alzheimer's-type pathology, intranasal route

    In 5xFAD mice, a transgenic mouse line bred to develop amyloid plaques and cognitive decline resembling Alzheimer's disease, intranasal GHK-Cu over 3 months was reported to delay measured cognitive decline on standard rodent memory tasks including a maze test, reduce amyloid plaque burden in the frontal cortex and hippocampus, and lower an inflammation marker (MCP-1) in the same brain regions, compared with 5xFAD mice given no GHK-Cu. The study authors' own framing is that these observations are early groundwork for further study, not an established result. This is a single preclinical mouse study using a genetically engineered disease model; it is not human data, and nothing here should be read as evidence about Alzheimer's disease or any other dementia in a person. 5xFAD transgenic mice (a genetic Alzheimer's-type pathology model), intranasal route Preclinical preliminary A single study, an early mechanistic observation, or a result whose interpretation is the authors' own inference. Open for the full finding and the paper it came from.

    In the literature

    GHK-Cu: transgenic mouse model of Alzheimer's-type pathology, intranasal route

    In 5xFAD mice, a transgenic mouse line bred to develop amyloid plaques and cognitive decline resembling Alzheimer's disease, intranasal GHK-Cu over 3 months was reported to delay measured cognitive decline on standard rodent memory tasks including a maze test, reduce amyloid plaque burden in the frontal cortex and hippocampus, and lower an inflammation marker (MCP-1) in the same brain regions, compared with 5xFAD mice given no GHK-Cu. The study authors' own framing is that these observations are early groundwork for further study, not an established result. This is a single preclinical mouse study using a genetically engineered disease model; it is not human data, and nothing here should be read as evidence about Alzheimer's disease or any other dementia in a person.^{References 12}

    Model5xFAD transgenic mice (a genetic Alzheimer's-type pathology model), intranasal route

    Confidence: preliminary

    A single study, an early mechanistic observation, or a result whose interpretation is the authors' own inference.

    Source

    Tucker M, Liao GY, Keely A, Park JY, Rosenfeld M, Wezeman J, Mangalindan R, Ratner D, Darvas M, Ladiges W. Behavioral and neuropathological features of Alzheimer's disease are attenuated in 5xFAD mice treated with intranasal GHK peptide. Aging Pathobiol Ther. 2024;6(3):102-108. DOI 10.31491/apt.2024.09.148. PMID 40766919.

    PubMed 40766919

    How this citation was checked

    NCBI E-utilities esummary and efetch were queried live and returned the 10 authors above, Aging Pathobiology and Therapeutics, 2024, volume 6, issue 3, pages 102 to 108, affiliation Department of Comparative Medicine, University of Washington, Seattle, with no author overlap with the 2015 review. The abstract confirms delayed cognitive decline, reduced amyloid plaques, and lowered inflammation markers in the frontal cortex and hippocampus, and the authors' own closing statement about providing a rationale for further study. It names the tested substance as GHK-Cu, the copper-bound form, despite the paper's title referring to it as 'GHK peptide.' Per this dossier's own house rule against a disease-model finding becoming a buyer-facing category, this finding renders as a research row only; see benefit_categories._note.

12. Studied for

    GHK-Cu: lifespan and stress-resistance pathways in Caenorhabditis elegans

    In the roundworm Caenorhabditis elegans, a commonly used laboratory model organism for aging and stress-pathway research, GHK-Cu was reported to extend lifespan and improve several age-related measures, including resistance to oxidative and thermal stress, motility, pharyngeal pumping, defecation rhythm, and reduced lipofuscin, a marker of cellular aging. Mechanistically, the authors report that GHK-Cu preserved mitochondrial membrane potential, shifted mitochondrial dynamics toward fusion, and activated 2 stress-response gene pathways, DAF-16 and SKN-1, conserved across many species including mammals. This is a single study in an invertebrate model organism, not a mammalian or human study; DAF-16 and SKN-1 have mammalian counterparts studied in aging research generally, but this study does not itself test or establish any effect in a mammal, and no anti-aging or longevity claim for people is made or implied from it in this dossier. Caenorhabditis elegans (invertebrate model organism) Preclinical preliminary A single study, an early mechanistic observation, or a result whose interpretation is the authors' own inference. Open for the full finding and the paper it came from.

    In the literature

    GHK-Cu: lifespan and stress-resistance pathways in Caenorhabditis elegans

    In the roundworm Caenorhabditis elegans, a commonly used laboratory model organism for aging and stress-pathway research, GHK-Cu was reported to extend lifespan and improve several age-related measures, including resistance to oxidative and thermal stress, motility, pharyngeal pumping, defecation rhythm, and reduced lipofuscin, a marker of cellular aging. Mechanistically, the authors report that GHK-Cu preserved mitochondrial membrane potential, shifted mitochondrial dynamics toward fusion, and activated 2 stress-response gene pathways, DAF-16 and SKN-1, conserved across many species including mammals. This is a single study in an invertebrate model organism, not a mammalian or human study; DAF-16 and SKN-1 have mammalian counterparts studied in aging research generally, but this study does not itself test or establish any effect in a mammal, and no anti-aging or longevity claim for people is made or implied from it in this dossier.^{References 13}

    ModelCaenorhabditis elegans (invertebrate model organism)

    Confidence: preliminary

    A single study, an early mechanistic observation, or a result whose interpretation is the authors' own inference.

    Source

    Wen H, Zhao K, Luo X, Pu J, Li Y, Dou Y, He J, Nie X, Ke Y, Zhou W. The GHK-Cu delays aging in Caenorhabditis elegans via coordinated regulation of mitochondrial function and activation of DAF-16/SKN-1 pathways. Biogerontology. 2026;27(3):100. DOI 10.1007/s10522-026-10444-x. PMID 42084774.

    PubMed 42084774

    How this citation was checked

    NCBI E-utilities esummary and efetch were queried live and returned the 10 authors above, Biogerontology, 2026, volume 27, issue 3, article 100, affiliation School of Medicine, Yunnan University and Kunming Medical University, China, with no author overlap with the 2015 review or the pulmonary and muscle cluster cited elsewhere in this dossier. The abstract confirms the extended lifespan, the stress-resistance and motility measures, reduced lipofuscin, the mitochondrial membrane potential and fusion-dynamics results, and DAF-16 and SKN-1 pathway activation. As the newest citation in this dossier, the DOI and PMID were checked specifically for a mis-transcribed or fabricated identifier; both resolve consistently to the same paper with no mismatch found. Per this dossier's benefit_categories._note, this finding has no corresponding market category for this compound and renders as a research row only.

1 strong / 3 moderate / 8 preliminaryRated by how many independent labs and how many kinds of experiment found the same thing.