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AEDR Peptide (Cardiogen): Molecular Characterization, Cardiac-Tissue Epigenetic Regulation, and Preclinical Research

AEDR Peptide (Cardiogen): Molecular Characterization, Cardiac-Tissue Epigenetic Regulation, and Preclinical Research

by | Oct 10, 2026 | Research

Cardiogen is a synthetic tetrapeptide bioregulator with the amino acid sequence Ala-Glu-Asp-Arg (AEDR).[1] It belongs to the class of short regulatory peptides referred to as Khavinson peptides, developed through research programs conducted at the St. Petersburg Institute of Bioregulation and Gerontology under the direction of Professor Vladimir Khavinson.[2] Cardiogen is classified as a cardiac-tissue-specific bioregulator, with preclinical investigations focusing on its putative role in modulating gene expression in cardiomyocytes and cardiac fibroblasts through direct nuclear interaction mechanisms.[2,3]

As a tetrapeptide of four amino acid residues, Cardiogen falls within the size range of ultrashort bioregulatory peptides that research suggests may penetrate cellular and nuclear membranes and interact with double-stranded DNA and histone proteins at physiologically relevant concentrations. The peptide is structurally related to other Khavinson tetrapeptides, including AEDL (Bronchogen, targeting bronchial epithelium) and AEDG (Epitalon, targeting pineal gland tissue), differing solely at position 4 where Arginine (Arg) substitutes for Leucine or Glycine, respectively. Research suggests this single amino acid variation at the C-terminus may underlie the tissue-specific activity observed across these structurally analogous compounds.[2]

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Cardiogen (20mg)
 

AEDR Historical Development

The Khavinson bioregulator peptide program originated in the late 1960s at what became the St. Petersburg Institute of Bioregulation and Gerontology.[9] The foundational hypothesis of this research program proposed that organ-specific short peptides, present endogenously in functional mammalian tissue, serve as physiological regulators of gene expression within their target tissues. The program further proposed that cellular age-associated decline in these peptide signals contributes to progressive deterioration of organ function, and that exogenous restoration of tissue-specific peptide bioregulators might attenuate age-related cellular dysfunction.[2,9]

 

Proposed Mechanism: Nuclear Penetration and Epigenetic Gene Regulation

The proposed mechanism of action of Cardiogen, consistent with that described for the broader class of Khavinson short peptides, involves cellular internalization, nuclear translocation, and subsequent interaction with specific DNA sequences within gene promoter regions and/or histone proteins.[2,3] This mechanism diverges fundamentally from classical receptor-mediated peptide signaling, in which ligands act at cell surface receptors to initiate intracellular signaling cascades. Instead, bioregulatory peptides of this class are proposed to function as direct epigenetic modulators operating within the nucleus.[2]

Experimental studies reportedly indicating nuclear penetration of short peptides were documented by Fedoreyeva et al. (2011),[3] who employed fluorescein isothiocyanate (FITC)-labeled short peptides and confocal microscopy in HeLa cell cultures. Marked fluorescence was detected in the cytoplasm, nucleus, and nucleolus following incubation with labeled peptides of the AEDG, EDR, and KEDG sequences, providing direct visualization of intracellular and nuclear translocation of ultrashort peptides.

Stern-Volmer fluorescence quenching analyses indicated sequence-specific interactions between peptides and single- and double-stranded deoxyribooligonucleotides in vitro, with binding constants varying according to peptide primary structure.³ Research suggests these findings might indicate that the specific sequence of AEDR, rather than non-specific charge interactions, may determine the selectivity of its DNA-binding activity.

A systematic analysis[7] of structural motifs in peptide-dsDNA interactions identified that short peptides with charged residue compositions exhibit preferential binding to defined nucleotide sequence motifs. Modeling data suggested that peptides within the AEDX family (where X varies at position 4) bind to overlapping but distinct promoter sequences depending on the C-terminal residue identity, potentially explaining observed tissue specificity differences between structurally related bioregulators.[7] Research suggests these computational models might indicate that Cardiogen’s arginine at position 4 may direct preferential interaction with promoter regions of cardiac-expressed genes. However, experimental validation at single-gene resolution remains limited in the published literature.

 

AEDR Scientific and Research Studies

 

Cardiomyocyte Proliferation and p53 Modulation in Organotypic Myocardial Tissue Culture

The most extensively cited preclinical investigation of Cardiogen is an organotypic tissue culture study by Chalisova et al. (2009).[4] This study examined the relevance of all 20 standard amino acids and the synthetic tetrapeptide Cardiogen on cell proliferation and apoptosis in myocardial tissue explants derived from young (3-month-old) and aged (24-month-old) murine cells. All substances were relevant at a uniform concentration of 10⁻¹² M in organotypic tissue culture systems, supporting direct comparison of cellular responses at equivalent molar concentrations.

Findings indicated that only 7 of the 20 individual amino acids stimulated cardiomyocyte proliferation in tissue from young animals, and only 2 amino acids retained proliferative activity in aged myocardial cells – a pattern interpreted as reflecting the documented impairment of amino acid transport mechanisms associated with cellular aging. Cardiogen, by contrast, was reported to produce substantial stimulation of cardiomyocyte proliferation in both young and aged tissue cultures.

Research suggests this differential response might indicate that the intact tetrapeptide sequence confers biological activity that is qualitatively distinct from that of its constituent amino acids individually. This interpretation was supported by a negative control experiment in which the four constituent amino acids of Cardiogen were evaluated individually at the same 10⁻¹² M concentration and did not replicate the tetrapeptide’s proliferative activity, suggesting the biological activity may reside in the intact peptide sequence rather than its component residues.[4]

Immunohistochemical analysis of p53 protein expression in Cardiogen-treated myocardial cultures indicated a reduction in p53 immunoreactivity relative to untreated controls. Research suggests this observation might indicate suppression of p53-mediated apoptotic signaling in cardiomyocytes, consistent with a proposed anti-apoptotic mechanism in cardiac tissue. p53 is established as a principal transcriptional activator of pro-apoptotic gene programs, and its downregulation in cardiomyocytes may be associated with reduced programmed cell death, a potentially significant finding in the context of cellular age-associated cardiomyocyte loss and myocardial remodeling biology.[10]

 

Cardioprotective Activity: Experimental Myocardial Infarction Model

Preclinical data cited in the Khavinson research program examined the relevance of Cardiogen in a rat model of experimental myocardial infarction (MI).[6] Findings reported within the review literature indicated that Cardiogen administration in this model was associated with a reduction in mortality approximately three-fold relative to untreated control animals. Histopathological observations suggested preservation of glycogen content in surviving myocardial tissue and reduced extent of necrotic tissue relative to controls, with investigators proposing that these implications may reflect Cardiogen’s putative role in stabilizing mitochondrial integrity and modulating apoptotic pathways in ischaemic cardiomyocytes.

Research suggests these preliminary observations might indicate that Cardiogen’s proposed anti-apoptotic and proliferative implications, documented at the cellular level in organotypic culture, may extend to physiological responses following acute myocardial injury in preclinical models. However, the mechanistic basis linking Cardiogen exposure to reduced mortality in this model has not been fully characterized, and independent replication of these findings in controlled experimental designs remains limited in the published literature.[6]

 

Tumor-Modifying Activity in Senescent Rat M-1 Sarcoma Models

An investigation[5] examined the tumor-modifying relevance of Cardiogen in senescent murine models bearing transplanted M-1 sarcoma. The study employed a concentration-dependent design in which Cardiogen was administered across multiple experimental groups at varying concentrations, with tumor growth, apoptotic index, and proliferative activity assessed at study endpoint.

Findings suggested that apoptosis levels in M-1 sarcoma tumor cells were elevated in all Cardiogen-treated experimental groups relative to the untreated control group, and that mitigation of tumor growth occurred in a concentration-dependent manner. Morphological analysis indicated that the observed tumor-mitigatory relevance was associated with development of hemorrhagic necrosis and stimulation of tumor cell apoptosis within the sarcoma tissue. Notably, proliferative activity parameters in the tumor were not significantly altered, leading the investigators to propose that the growth-mitigating relevance was not attributable to a direct cytostatic mechanism on tumor cells but rather operated through modulation of the tumor’s vascular network.

Research suggests these findings might indicate a dual context-dependent relevance of Cardiogen on apoptotic regulation: a proposed anti-apoptotic, pro-proliferative relevance in normal cardiac tissue contrasted with pro-apoptotic implications in malignant tumor tissue. This apparent cell-type specificity of apoptotic modulation may reflect differential expression of Cardiogen’s proposed DNA-binding targets across normal and transformed cell populations, though the precise molecular basis of this divergence has not been experimentally characterized.[5]

 

Cardiovascular Inflammaging and SASP: AEDR Peptide Regulation

A 2022 review[6] systematically examined the molecular landscape of the senescence-associated secretory phenotype (SASP) and inflammaging in cells of the cardiovascular system, with a specific focus on identifying peptide regulatory targets. SASP is characterized by the secretion of a broad spectrum of pro-inflammatory cytokines (including IL-1α/β, IL-6, IL-8, TNFα, TGFβ1, NF-κB), matrix metalloproteinases, adhesion molecules, and extracellular vesicles from senescent vascular smooth muscle cells (VSMCs), endotheliocytes, and cardiomyocytes. This chronic, low-grade secretory profile is proposed to drive systemic inflammaging and contribute to progression of cellular age-associated cardiovascular pathology including atherosclerosis, coronary artery disease, and myocardial infarction.[6]

Within this review, the AEDR tetrapeptide was identified as exhibiting cardioprotective properties with documented reduction in post-MI mortality in the experimental rat model referenced above. The review characterized the molecular targets of AEDR regulation within the SASP framework, identifying anti-proliferative proteins (p16, p19, p21, p38, p53), pro-inflammatory cytokines, and sirtuin family members as components of the SASP molecular signature that may be subject to peptide regulation. Research suggests that AEDR’s proposed modulation of p53 in cardiomyocytes may intersect with the p53-dependent pathways through which SASP is initiated and maintained in senescent cardiovascular cells, potentially positioning the peptide as a candidate tool for studying the molecular interface between cellular senescence and myocardial biology.

 

Structural Basis of Peptide-DNA Interactions: Broader Mechanistic Framework

A systematic computational study[7] employed a genome-wide structural motif search algorithm to identify binding complementarity between short Khavinson bioregulatory peptides and double-stranded DNA sequences. The analysis mapped the DNA sequence motifs to which specific peptides, including members of the AEDX tetrapeptide family, exhibit preferential binding affinity based on structural and electrostatic complementarity principles.

Findings from this computational analysis indicated that peptides within the AED-containing family bind to defined short nucleotide sequence motifs, with the identity of the C-terminal residue supporting the precise genomic binding loci. The study identified that these binding motifs are enriched within the promoter regions of genes expressed in a tissue-specific manner, consistent with the proposed tissue specificity of individual bioregulatory peptides.⁷ Research suggests these computational predictions might provide a structural model for understanding how AEDR may selectively engage cardiac gene promoters. However, empirical mapping of AEDR-specific promoter binding in cardiac tissue has not been published as an independent study.

Complementary investigations documented by Khavinson et al. (2013)[8] constructed spatial molecular models of DNA-peptide complexes for 19 short peptides using molecular docking methodology, identifying that peptides within structurally related families share DNA binding sites in some cases while exhibiting distinct binding orientations in others. For the AEDL and EDL sequences, binding was mapped to the CTCC motif, while related peptides were mapped to ACCT and AGAT motifs. Research suggests extending this docking-based modeling framework to AEDR may identify specific cardiac gene promoter binding sites that may be evaluated experimentally, representing a prospective direction for mechanistic validation of the peptide’s proposed cardiac specificity.

Disclaimer: The products mentioned are not intended for human or animal consumption. Research chemicals are intended solely for laboratory experimentation and/or in-vitro testing. Bodily introduction of any sort is strictly prohibited by law. All purchases are limited to licensed researchers and/or qualified professionals. All information shared in this article is for educational purposes only.

 

References:

  1. National Center for Biotechnology Information. PubChem Compound Summary for CID 11583989, H-Ala-Glu-Asp-Arg-OH (Cardiogen). 2024. Available from: https://pubchem.ncbi.nlm.nih.gov/compound/H-Ala-Glu-Asp-Arg-OH
  2. Khavinson VK, Popovich IG, Linkova NS, Mironova ES, Ilina AR. Peptide Regulation of Gene Expression: A Systematic Review. Molecules. 2021;26(22):7053. doi:10.3390/molecules26227053. PMID: 34834147. Available from: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8619776/
  3. Fedoreyeva LI, Kireev II, Khavinson VKh, Vanyushin BF. Penetration of short fluorescence-labeled peptides into the nucleus in HeLa cells and in vitro specific interaction of the peptides with deoxyribooligonucleotides and DNA. Biochemistry (Moscow). 2011;76(11):1210-1219. doi:10.1134/S0006297911110022. Available from: https://link.springer.com/article/10.1134/S0006297911110022
  4. Chalisova NI, Lesniak VV, Balykina NA, Urt’eva SA, Urt’eva TA, Sukhonos IuA, Zhekalov AN. The effect of the amino acids and cardiogen on the development of myocardial tissue culture from young and old rats. Adv Gerontol (Uspekhi Gerontologii). 2009;22(3):409-13. PMID: 20210190. Available from: https://pubmed.ncbi.nlm.nih.gov/20210190/
  5. Levdik NV, Knyazkin IV. Tumor-modifying effect of cardiogen peptide on M-1 sarcoma in senescent rats. Bull Exp Biol Med. 2009;148(3):433-436. doi:10.1007/s10517-010-0730-9. PMID: 20396706. Available from: https://pubmed.ncbi.nlm.nih.gov/20396706/
  6. Khavinson V, Linkova N, Dyatlova A, Kantemirova R, Kozlov K. Senescence-Associated Secretory Phenotype of Cardiovascular System Cells and Inflammaging: Perspectives of Peptide Regulation. Cells. 2022;12(1):106. doi:10.3390/cells12010106. Available from: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9818427/
  7. Kolchina N, Khavinson V, Linkova N, Yakimov A, Baitin D, Afanasyeva A, Petukhov M. Systematic search for structural motifs of peptide binding to double-stranded DNA. Nucleic Acids Res. 2019;47(20):10553-10563. doi:10.1093/nar/gkz850. PMID: 31586398. Available from: https://pubmed.ncbi.nlm.nih.gov/31586398/
  8. Khavinson VK, Linkova NS, Tarnovskaya SI, Shataeva LK, Yakutseni PP. Short cell-penetrating peptides: a model of interactions with gene promoter sites. Bull Exp Biol Med. 2013;154(3):403-410. doi:10.1007/s10517-013-1965-0. PMID: 24771399. Available from: https://pubmed.ncbi.nlm.nih.gov/24771399/
  9. Anisimov VN, Khavinson VK. Peptide bioregulation of aging: results and prospects. Biogerontology. 2010;11(2):139-149. doi:10.1007/s10522-009-9249-8. PMID: 19830585. Available from: https://link.springer.com/article/10.1007/s10522-009-9249-8
  10. Khavinson VK, Tarnovskaya SI, Linkova NS, Gutop EO, Elashkina EV. Epigenetic aspects of peptidergic regulation of vascular endothelial cell proliferation during aging. Adv Gerontol. 2015;5(4):250-256. doi:10.1134/S2079057015040116. Available from: https://link.springer.com/article/10.1134/S2079057015040116
KLOW Blend (BPC-157, TB-500, GHK-Cu, KPV): Molecular Characterization, Receptor Mechanisms, and Multi-Pathway Tissue Research

KLOW Blend (BPC-157, TB-500, GHK-Cu, KPV): Molecular Characterization, Receptor Mechanisms, and Multi-Pathway Tissue Research

by | Aug 29, 2026 | Research

The KLOW blend is a research-grade formulation comprising four structurally distinct peptides: BPC-157 (Body Protection Compound-157), TB-500 (Ac-LKKTETQ, the actin-binding fragment of thymosin beta-4), GHK-Cu (glycyl-L-histidyl-L-lysine copper complex), and KPV (Lys-Pro-Val). Each constituent engages a pharmacologically discrete molecular target. BPC-157 acts principally via VEGFR2-mediated angiogenesis and the nitric oxide signaling axis.[1][2] TB-500 functions through G-actin sequestration and integrin-linked kinase (ILK) activation.[5][6]

GHK-Cu modulates extracellular matrix (ECM) remodeling via matrix metalloproteinase regulation and collagen synthesis.[7][8] KPV mitigates NF-κB-dependent inflammatory signaling through intracellular uptake mediated by the PepT1 transporter.[10] This convergent but non-redundant receptor architecture may provide a research framework for studying multi-pathway tissue biology, inflammation modulation, and cellular regeneration across diverse preclinical models.

Featured Product

BPC-157 & KPV & TB-500 & GHK-Cu Blend (KLOW) - 80mg
 

KLOW Blend Historical Development of Constituent Peptides

BPC-157 was first isolated and characterized from gastric juice by Professor Predrag Sikirić and colleagues at the University of Zagreb, Croatia, in the early 1990s.[1] The compound (CAS 137525-51-0; also designated PL 14736) was identified as a 15-amino acid partial sequence of the endogenous protection compound protein, exhibiting cytoprotective properties in gastric mucosal models. Its stability relative to other bioactive peptides-attributable to its proline-rich central motif-facilitated investigation across a range of murine tissue systems.[3]

TB-500 is a synthetic heptapeptide corresponding to residues 17–23 of full-length thymosin beta-4 (β4), a ubiquitous 43-amino acid G-actin sequestering protein originally isolated from bovine thymus in the 1960s.[4][6] The designation TB-500 refers to the acetylated active fragment Ac-LKKTETQ, which retains the actin-binding motif of the parent molecule. The full-length β4 molecule underpins the preponderance of the published academic literature, with TB-500 used in research contexts to access this actin-regulatory biology.[4]

GHK-Cu was isolated from plasma by Pickart in 1973, originally identified as a factor within the albumin fraction that induced aged liver cells to synthesize proteins with a profile resembling that of younger tissue.[7] Subsequent investigations established that this activity resided in the tripeptide glycyl-L-histidyl-L-lysine, which forms a stable chelate with copper(II) ions (GHK-Cu). Research has since characterized GHK-Cu as a regulator of ECM synthesis, collagen production, and tissue remodeling processes.[7][8]

KPV (Lys-Pro-Val) corresponds to C-terminal residues 11–13 of α-melanocyte-stimulating hormone (α-MSH), a 13-amino acid neuropeptide of pituitary origin. Research investigations identified that this tripeptide fragment retains the anti-inflammatory activity of the parent hormone while lacking its pigmentation-inducing and hunger hormone-modulating implications.[10][11] The small molecular size of KPV may confer oral stability and facilitate intracellular entry via di/tripeptide transporters, properties that have been examined in gastrointestinal and inflammatory research models.

 

KLOW Blend Receptor Mechanisms and Intracellular Signaling

BPC-157 engages VEGFR2 (vascular endothelial growth factor receptor 2), a receptor tyrosine kinase expressed on endothelial cells. VEGFR2 activation may initiate downstream phosphorylation cascades through the Akt-eNOS axis, promoting nitric oxide (NO) synthesis and endothelial cell proliferation.[2] Separately, BPC-157 has been observed to activate the focal adhesion kinase (FAK)-paxillin pathway in tendon fibroblasts, a signaling axis associated with increased cell migration and cytoskeletal reorganization.[1] Research suggests BPC-157 may also upregulate growth hormone receptor expression in fibroblast populations, potentially potentiating GH-mediated repair signaling.[3]

TB-500’s primary mechanism involves sequestration of monomeric G-actin, maintaining the intracellular pool of actin in a polymerization-competent state and enabling rapid cytoskeletal reorganization during cell migration.[6] Integrin-linked kinase (ILK) activation represents a downstream consequence of TB-500/β4 exposure in cardiac and endothelial cells, initiating Akt-mediated survival signaling.⁵ In cardiac injury models, ILK and Akt upregulation following β4 exposure has been associated with supported early cardiomyocyte survival and neovascularisation.

GHK-Cu engages fibroblasts and dermal cells to upregulate matrix metalloproteinase-2 (MMP-2), an enzyme involved in ECM remodeling and turnover of fibrillar collagen.[8] Concurrently, GHK-Cu may stimulate synthesis of type I collagen, elastin, and sulfated glycosaminoglycans – key structural ECM components. Research suggests these dual MMP-upregulatory and collagen-stimulatory implications might indicate a coordinated ECM remodeling capacity, consistent with its historical characterization as a wound recovery activator.

KPV enters intestinal epithelial cells and immune cells primarily through the PepT1 di/tripeptide transporter, an uptake mechanism that is upregulated in inflamed intestinal tissue during inflammatory bowel conditions. Once internalized, KPV mitigates NF-κB nuclear translocation by attenuating IkB-α degradation, thereby reducing transcriptional activation of pro-inflammatory cytokine genes including IL-8, TNF-α, and IL-1β.[10][11] Research suggests this intracellular NF-κB mitigation may operate independently of melanocortin receptor (MCR) engagement, distinguishing its mechanism from the parent α-MSH molecule.

 

KLOW Blend Scientific and Research Studies

 

BPC-157: FAK-Paxillin Pathway Activation and Tendon Fibroblast Biology

Researchers studied the mechanistic basis of BPC-157’s implications on tendon recovery using cultured murine model Achilles tendon fibroblasts and tendon explant outgrowth assays.[1] BPC-157 significantly accelerated the outgrowth of tendon fibroblasts from explant cultures and markedly increased in vitro fibroblast migration in a concentration-dependent manner. Cell proliferation, as measured by MTT assay, was not directly altered, suggesting that the primary implication may involve cell motility and tissue invasion rather than proliferative expansion.

Western blot analysis indicated that BPC-157 produced concentration-dependent increases in the phosphorylation of FAK and paxillin-key components of focal adhesion complexes-without altering total protein levels. FITC-phalloidin staining further suggested supported F-actin formation in BPC-157-treated fibroblasts. Research suggests these findings might indicate that BPC-157 promotes tendon cell migration and structural reorganization through activation of the FAK-paxillin focal adhesion pathway, potentially contributing to observed accelerations in tendon wound recovery in preclinical models.

 

BPC-157: VEGFR2-Mediated Angiogenesis and Vascular Signaling

Hsieh et al. (2017)[2] examined the angiogenic signaling mechanisms of BPC-157 in endothelial cell models and correlated receptor-level activity with vascular outcomes. Findings suggested that BPC-157 may upregulate VEGFR2 expression in endothelial cells and activate downstream Akt-eNOS phosphorylation cascades, which are associated with endothelial nitric oxide production and angiogenic sprouting. These receptor-level observations were correlated with supported vessel formation markers in the murine models studied.

Brcic et al. (2009)[3] examined the angiogenic potential of BPC-157 across muscle tissue and murine tendon recovery research models, correlating peptide exposure with VEGF expression using cell culture and animal systems. Observations suggested that BPC-157 may stimulate angiogenesis by upregulating VEGF expression at wound sites, with the angiogenic response appearing closely associated with the recovery progression documented histologically across tissue compartments. Research suggests these findings might indicate that VEGFR2-driven angiogenesis represents a mechanistically central element of BPC-157’s tissue repair activity in preclinical settings.

 

TB-500 (Thymosin Beta-4): ILK-Akt Activation and Cardiac Cell Survival

Bock-Marquette et al. (2004)[5] studied the role of thymosin beta-4 in cardiac cell biology following myocardial injury. In a murine coronary artery ligation model, β4 exposure was associated with upregulation of integrin-linked kinase (ILK) and Akt activity within the cardiac tissue. supported early cardiomyocyte survival was observed in treated animals, alongside support for cardiac functional parameters relative to control groups.

The investigators further characterized β4’s implications on cardiac progenitor cell migration in vitro, finding that the peptide promoted cardiomyocyte migration through ILK-dependent pathways. Research suggests these findings might indicate that β4-mediated ILK-Akt signaling may represent a cardioprotective mechanism with potential relevance to preclinical models of ischemic cardiac injury. These observations provide mechanistic context for TB-500’s G-actin-based biology in cardiac tissue, where cytoskeletal regulation is central to cell migration and structural repair.

 

TB-500 (Thymosin Beta-4): Epicardial Progenitor Mobilization and Neovascularisation

Smart et al. (2007)[12] examined the capacity of thymosin beta-4 to mobilize adult epicardial progenitor cells and stimulate neovascularisation in a murine cardiac injury model. Following myocardial infarction, β4 exposure was associated with reactivation of dormant epicardial progenitor populations and promotion of new coronary vessel formation. The investigators proposed that β4 may stimulate the re-expression of embryonic epicardial genes, enabling adult epicardial cells to contribute to vascular repair processes.

Actin regulation by the β4 molecule was identified as integral to the progenitor mobilization response, linking the peptide’s primary biochemical function (G-actin sequestration) to downstream biological outcomes in a clinically relevant injury model. Research suggests these findings might indicate that TB-500’s actin-regulatory mechanism may drive paracrine and regenerative signalling beyond the immediate site of peptide engagement.

 

GHK-Cu: ECM Remodeling, Collagen Synthesis, and Glycosaminoglycan Production

Researchers conducted a comprehensive review[7] of GHK-Cu’s biological activity across dermatology and wound biology models. Investigations cited therein indicated that GHK-Cu may stimulate collagen synthesis in fibroblast cultures, accelerate wound contraction and epithelialization, and promote the take of transplanted dermal cells in murine models. The review further identified GHK-Cu’s capacity to upregulate MMP-2 expression, facilitating ECM remodeling and clearance of damaged matrix proteins. Endogenous plasma GHK concentrations of approximately 200 ng/mL at age 20 were reported to decline to approximately 80 ng/mL by age 60, with this decline noted to correlate with observed reductions in tissue regenerative capacity.

Scientists[8] examined the role of matrikines-ECM-derived peptide fragments including GHK-in the regulation of ECM degradation and synthesis. Findings supported the characterization of GHK as a matrikine capable of modulating MMP expression and promoting glycosaminoglycan synthesis in wound tissue models, implications potentially relevant to the maintenance of structural ECM integrity during repair processes. Research suggests these findings might indicate that GHK-Cu may function as an endogenous ECM regulatory signal with broad relevance to tissue homeostasis research.

 

GHK-Cu: Anti-Inflammatory Activity in Acute Tissue Injury Models

Research was conducted studying the implications of GHK-Cu in a murine model of lipopolysaccharide (LPS)-induced acute lung injury (ALI). GHK-Cu exposure was associated with suppression of pro-inflammatory mediators including reactive oxygen species (ROS), nitric oxide (NO), and cyclooxygenase-2 (COX-2) in pulmonary tissue. Reductions in transforming growth factor-beta (TGF-β) and tumor necrosis factor-alpha (TNF-α) concentrations were also reported in treated animals relative to untreated controls.[9]

Histopathological evaluation of lung tissue suggested reduced inflammatory infiltrate and structural preservation in GHK-Cu-exposed groups. Research suggests these observations might indicate that GHK-Cu may engage anti-inflammatory pathways beyond its ECM-regulatory function, potentially through modulation of iron-mediated oxidative stress and cytokine regulatory networks. These findings may complement the anti-inflammatory mechanism of KPV within the KLOW blend by providing an additional, mechanistically distinct pathway of inflammatory modulation.

 

KPV: PepT1-Mediated Uptake and NF-κB Mitigation in Intestinal Inflammation Models

Dalmasso et al. (2008)[10] studied the mechanism underlying KPV’s anti-inflammatory activity in intestinal epithelial and immune cell models. Using intestinal epithelial cell lines (Caco2-BBE and HT29-Cl.19A) and Jurkat T cells stimulated with pro-inflammatory cytokines, the investigators examined whether KPV’s anti-inflammatory implication required the PepT1 di/tripeptide transporter. Uptake experiments using radiolabelled [3H]KPV and competitive mitigation assays confirmed PepT1-mediated intracellular entry in PepT1-expressing cells.

Mechanistic assays indicated that KPV attenuated NF-κB-dependent gene expression by mitigating IkB-α degradation, with downstream reductions in IL-8 mRNA expression. In two murine colitis models (DSS-induced and CD45RBhi transfer colitis), systemic KPV exposure was associated with attenuation of colonic inflammation, as assessed by histological scoring and cytokine measurement. Research suggests these findings might indicate that PepT1-mediated intracellular delivery may be a prerequisite for KPV’s anti-inflammatory activity in epithelial tissues, and that upregulation of PepT1 during intestinal inflammation may support local peptide uptake at inflamed mucosal sites.

 

KPV: Melanocortin-Derived Anti-Inflammatory Activity in IBD Models

Scientists evaluated KPV’s potential in two established murine intestinal inflammation models: DSS-induced colitis and CD45RBhi transfer colitis. The study additionally examined KPV activity in animals carrying a non-functional melanocortin-1 receptor (MC1Re/e), enabling dissection of receptor-dependent from receptor-independent anti-inflammatory mechanisms.[11]

Findings suggested that KPV attenuated clinical and histological indices of colitis in both models, and that this anti-inflammatory activity was preserved in MC1R-deficient animals. Research suggests these results might indicate that KPV’s gastrointestinal anti-inflammatory mechanism may not require functional MCR engagement, consistent with the NF-κB-centric, receptor-independent intracellular pathway characterized by Dalmasso et al.[11] The mechanistic independence of KPV from its parent hormone’s receptor may have implications for the design of research models investigating targeted mucosal anti-inflammatory signaling.

Disclaimer: The products mentioned are not intended for human or animal consumption. Research chemicals are intended solely for laboratory experimentation and/or in-vitro testing. Bodily introduction of any sort is strictly prohibited by law. All purchases are limited to licensed researchers and/or qualified professionals. All information shared in this article is for educational purposes only.

 

References:

  1. Chang CH, Tsai WC, Lin MS, Hsu YH, Pang JH. The promoting effect of pentadecapeptide BPC 157 on tendon healing involves tendon outgrowth, cell survival, and cell migration. J Appl Physiol. 2011;110(3):774-780. doi:10.1152/japplphysiol.00945.2010. PMID: 21030672. Available from: https://pubmed.ncbi.nlm.nih.gov/21030672/
  2. Hsieh MJ, Liu HT, Wang CN, Huang HY, Lin Y, Ko YS, et al. Therapeutic potential of pro-angiogenic BPC157 is associated with VEGFR2 activation and up-regulation. J Mol Med (Berl). 2017;95(3):323-333. doi:10.1007/s00109-016-1488-y. Available from: https://link.springer.com/article/10.1007/s00109-016-1488-y
  3. Brcic L, Brcic I, Staresinic M, Novinscak T, Sikiric P, Seiwerth S. Modulatory effect of gastric pentadecapeptide BPC 157 on angiogenesis in muscle and tendon healing. J Physiol Pharmacol. 2009;60(Suppl 7):191-196. Available from: https://www.researchgate.net/publication/51443032
  4. Goldstein AL, Hannappel E, Sosne G, Kleinman HK. Thymosin β4: a multi-functional regenerative peptide. Basic properties and clinical applications. Expert Opin Biol Ther. 2012;12(1):37-51. doi:10.1517/14712598.2012.634793. PMID: 22136436. Available from: https://pubmed.ncbi.nlm.nih.gov/22136436/
  5. Bock-Marquette I, Saxena A, White MD, Dimaio JM, Srivastava D. Thymosin beta4 activates integrin-linked kinase and promotes cardiac cell migration, survival and cardiac repair. Nature. 2004;432(7016):466-472. doi:10.1038/nature03040. PMID: 15565145. Available from: https://pubmed.ncbi.nlm.nih.gov/15565145/
  6. Huff T, Müller CS, Otto AM, Netzker R, Hannappel E. β-Thymosins, small acidic peptides with multiple functions. Int J Biochem Cell Biol. 2001;33(3):205-220. doi:10.1016/s1357-2725(00)00087-x. PMID: 11311852. Available from: https://pubmed.ncbi.nlm.nih.gov/11311852/
  7. 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. PMID: 26236730. Available from: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4508379/
  8. Maquart FX, Bellon G, Pasco S, Monboisse JC. Matrikines in the regulation of extracellular matrix degradation. Biochimie. 2005;87(3-4):353-360. doi:10.1016/j.biochi.2004.10.013. PMID: 15781325. Available from: https://pubmed.ncbi.nlm.nih.gov/15781325/
  9. Park JR, Lee H, Kim SI, Yang SR. The tri-peptide GHK-Cu complex ameliorates lipopolysaccharide-induced acute lung injury in mice. Oncotarget. 2016;7(36):58405-58417. doi:10.18632/oncotarget.11168. PMID: 27542263. Available from: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5295439/
  10. Dalmasso G, Charrier-Hisamuddin L, Nguyen HT, Yan Y, Sitaraman S, Merlin D. PepT1-mediated tripeptide KPV uptake reduces intestinal inflammation. Gastroenterology. 2008;134(1):166-178. doi:10.1053/j.gastro.2007.10.026. PMID: 18061177. Available from: https://www.gastrojournal.org/article/S0016-5085(07)01852-5/fulltext
  11. Kannengiesser K, Maaser C, Heidemann J, Luegering A, Ross M, Brzoska T, et al. Melanocortin-derived tripeptide KPV has anti-inflammatory potential in murine models of inflammatory bowel disease. Inflamm Bowel Dis. 2008;14(3):324-331. doi:10.1002/ibd.20334. Available from: https://academic.oup.com/ibdjournal/article-abstract/14/3/324/4653598
  12. Smart N, Risebro CA, Melville AA, Moses K, Schwartz RJ, Bhatt DL, et al. Thymosin beta4 induces adult epicardial progenitor mobilization and neovascularisation. Nature. 2007;445(7124):177-182. doi:10.1038/nature05383. PMID: 17187048. Available from: https://pubmed.ncbi.nlm.nih.gov/17187048/
EDR (Pinealon): Molecular Characterization, Epigenetic Mechanisms, and Neuroprotective Research

EDR (Pinealon): Molecular Characterization, Epigenetic Mechanisms, and Neuroprotective Research

by | Aug 3, 2026 | Research

EDR is a synthetic tripeptide composed of three amino acids in the sequence L-glutamic acid-L-aspartic acid-L-arginine (Glu-Asp-Arg), designated in single-letter code as Pinealon.[1] It is classified within the Khavinson peptide bioregulator framework as a cytogen, a short peptide hypothesized to modulate gene expression in targeted tissue types through direct interaction with cellular DNA.

The term EDR reflects early hypotheses regarding the peptide’s proposed support for neuroendocrine functions associated with the pineal gland, including circadian rhythm regulation and melatonin biosynthesis pathways. However, the compound was isolated from Cortexin, a polypeptide complex derived from the cerebral cortex of bovine neonates, rather than from pineal tissue directly.[3] This isolation positioned EDR within a broader class of neuroprotective peptide bioregulators hypothesized to reproduce the regulatory activity of endogenous CNS short peptides at the transcriptional level.

Featured Product

Pinealon (20mg)
 

EDR Historical Development

Pinealon was identified and characterized by Vladimir Khavinson and colleagues at the Saint Petersburg Institute of Bioregulation and Gerontology (Russia). Its development forms part of a systematic research program initiated in the 1970s to investigate short peptide fractions isolated from organ-specific polypeptide preparations and their capacity to modulate tissue-specific gene expression.[3] The biological rationale underlying Pinealon’s development rested on observations that endogenous di- and tripeptides within the CNS may participate in transcriptional regulation of genes relevant to neuronal survival, antioxidant defense, and neuroendocrine signaling.[3]

 

EDR Proposed Mechanism of Action

The proposed mechanism of Pinealon’s biological activity diverges from receptor-mediated signaling paradigms. Research suggests the peptide may cross both plasma membranes and the nuclear envelope, facilitated by its small molecular size and the physicochemical properties of the arginine residue.[3] Once intranuclear, Pinealon is hypothesized to interact with chromatin and modulate transcription factor binding at specific gene promoter sequences, functioning as an epigenetic regulator rather than a classical receptor agonist.[3,4]

Research data collected in laboratory settings suggests that EDR may regulate the expression of MAPK signaling pathway components, specifically ERK1/2, which may in turn support oxidative stress responses, anti-apoptotic gene programs, and neuroplasticity-related transcription in neural cell populations.[2,3] Research suggests this ERK1/2-associated signaling might provide a mechanistic link between Pinealon’s proposed DNA interactions and its observed downstream implications on ROS accumulation, cell cycle dynamics, and neuronal morphological integrity.[2]

 

EDR Scientific and Research Studies

 

Free Radical Suppression and Cell Viability in Neural Models

A foundational in vitro investigation[2] examined the implications of Pinealon on cell viability and oxidative stress parameters in three cell models: cerebellar granule cells, neutrophils, and PC12 pheochromocytoma cells exposed to receptor-dependent and receptor-independent oxidative stress conditions. The study characterized dose-dependent implications of the EDR peptide on ROS accumulation, necrotic cell death (assessed by propidium iodide positivity), and ERK1/2 activation.[2]

Findings suggested that EDR produced concentration-dependent restriction of ROS accumulation and reduced the proportion of propidium-iodide-positive necrotic cells across the evaluated cell types under oxidative challenge. The antioxidant and cytoprotective implications were reported to saturate at lower peptide concentrations, while cell-cycle modulatory implications associated with delayed ERK1/2 activation continued at higher concentrations. Research suggests these differential concentration-response profiles might indicate mechanistically distinct implications at the antioxidant and genomic levels, potentially consistent with a dual mode of action involving both direct free radical quenching and downstream transcriptional regulation.

 

Prenatal Neuroprotection in Hyperhomocysteinemia Models

Arutjunyan et al. (2012)[6] investigated the neuroprotective capacity of Pinealon in a murine model of prenatal hyperhomocysteinemia, a condition associated with elevated maternal homocysteine levels, oxidative CNS stress, and adverse neurodevelopmental outcomes in offspring. Pregnant rats were exposed to elevated homocysteine during gestation, and offspring were subsequently evaluated for markers of oxidative neuronal injury and behavioral parameters.

Findings suggested that Pinealon may attenuate oxidative stress markers in the brains of offspring from hyperhomocysteinaemic dams, with associated implications for ROS levels and indices of neuronal integrity. Behavioral assessments suggested partial preservation of motor coordination and cognitive parameters relative to hyperhomocysteinaemic control groups that received no intervention. Research suggests these findings might indicate that EDR may exert neuroprotective implications during critical neurodevelopmental windows under conditions of oxidative CNS insult. However, further independent replication in comparable prenatal models would be required to substantiate these observations.

 

Cytokine Regulation and Caspase-3 Activity Under Hypoxic Conditions

Another study[8] examined the implications of Pinealon in combination with the polypeptide complex Cortexin on cytokine profiles in blood serum and caspase-3 activity in the brains of aged rats subjected to acute hypoxia. The experimental model employed 18-month-old rats, representing an aged cohort with heightened susceptibility to hypoxia-induced neuronal injury.

Observations suggested that the combined Pinealon and Cortexin intervention was associated with modulation of pro-inflammatory cytokine concentrations in serum and attenuation of caspase-3 activity in brain tissue relative to hypoxia-exposed controls. Caspase-3 is a terminal protease in apoptotic cascades, and its activity serves as a widely employed surrogate marker of apoptotic neuronal death in preclinical models. Research suggests these findings might indicate that Pinealon may contribute to anti-apoptotic signaling in aged neural tissue under acute hypoxic challenge, potentially through regulation of upstream pro-inflammatory or oxidative stress pathways that converge on caspase-3 activation.

 

Serotonin Expression in Brain Cortex Cells

Khavinson et al. (2014)[9] investigated the support of short peptides, including EDR, on serotonin expression in cortical brain cells. Serotonin (5-hydroxytryptamine, 5-HT) is a monoamine neurotransmitter with pleiotropic functions in CNS signaling, including roles in behavioral regulation, circadian rhythm entrainment, and neuroprotective signaling cascades. The study evaluated whether Pinealon exposure might modulate serotonergic gene expression or serotonin synthesis in cortical cell preparations.

Findings suggested that EDR and related short peptides may support serotonin expression levels in cortical brain cell cultures. Research suggests these observations might indicate a potential neuromodulatory role for Pinealon within cortical serotonergic pathways, providing a mechanistic connection between EDR’s proposed transcriptional regulatory activity and neuroendocrine signaling networks in the central nervous system. These findings may be relevant to broader investigations of circadian biology and neuroendocrine axis regulation in the context of peptide bioregulator research.

 

Dendritic Spine Restoration in Alzheimer’s Disease Cell Models

Kraskovskaya et al. (2017)[7] examined the capacity of EDR and the related tripeptide KED (Lys-Glu-Asp) to restore dendritic spine density in neuronal cultures under conditions modeling Alzheimer’s disease (AD) synaptotoxicity. Dendritic spines constitute the postsynaptic sites of excitatory synaptic contacts, and their progressive loss is a recognized early pathological feature of AD, correlating with cognitive decline in preclinical and clinical settings.

In vitro observations suggested that the EDR peptide was associated with partial restoration of neuronal spine number in AD-model preparations, with implications attributed to modulation of gene expression networks involved in synaptic plasticity and cytoskeletal organization.[7] Research suggests these findings might indicate that Pinealon may attenuate synaptotoxic processes in AD-relevant neuronal models, potentially through the proposed epigenetic regulatory mechanism involving promoter-region DNA interactions. Independent replication of these findings in additional AD cell models would be required to establish the generalisability of these observations.

 

Dendritic Spine Preservation and Neuroplasticity in Transgenic Alzheimer’s Disease Murine Models

Khavinson et al. (2021)[4] extended the investigation of EDR neuroprotection to a 5xFAD transgenic murine model of Alzheimer’s disease, a model characterized by five familial AD mutations producing aggressive amyloid accumulation, progressive synapse loss, and cognitive impairment. The study examined whether EDR and KED tripeptides may preserve dendritic spines and neuroplasticity markers in this stringent transgenic model.

Findings suggested that EDR peptide exposure was associated with mitigation of dendritic spine loss in 5xFAD mice compared to transgenic controls receiving no intervention, with implications for hippocampal neuroplasticity markers. Molecular docking analyses conducted within the same study identified putative binding sites for the EDR peptide within the promoter sequences of genes including CASP3, NES, GAP43, APOE, SOD2, PPARA, PPARG, and GPX1, providing computational support for the proposed epigenetic mechanism. Research suggests these preclinical data might indicate a potential role for Pinealon in attenuating synaptic pathology in AD-relevant research models, though translation to clinical settings would require further investigation.

 

Neuroprotection in Huntington’s Disease Models

Khavinson et al. (2017)[10] evaluated the neuroprotective activity of the EDR peptide in a murine model of Huntington’s disease (HD), a neurodegenerative disorder characterized by polyglutamine-expanded huntingtin protein aggregation, striatal neurodegeneration, and progressive motor and cognitive deterioration. The model employed 3-nitropropionic acid (3-NPA) to recapitulate key aspects of HD-associated neuronal injury.[10]

Observations suggested that EDR exposure was associated with attenuation of HD-relevant neuronal pathology in the experimental model, with findings interpreted as consistent with the peptide’s proposed anti-apoptotic and antioxidant mechanisms. Research suggests these findings might indicate that Pinealon’s neuroprotective activity may extend across neurodegeneration-relevant models beyond Alzheimer’s disease, potentially reflecting the broad genomic regulatory targets proposed by computational docking investigations.

 

Protection of Fibroblast-Derived Neurons from Age-Related Changes

A recent study[5] employed a novel in vitro model of neuronal aging based on the direct transdifferentiation of aged dermal fibroblasts from elderly donors into induced cortical neurons. This experimental design offered a methodological advance over rodent or established cell line models, as the resulting neurons retained epigenetic aging signatures from the original donor fibroblasts, enabling investigation of neuroprotective implications in a cellular context reflective of biological aging.

Findings suggested that EDR peptide promoted arborization of the dendritic tree in the induced neurons, increasing both the number of primary processes and the total length of dendrites relative to controls receiving no intervention. Additionally, immunofluorescent analysis indicated that EDR reduced oxidative DNA damage in the aged induced neurons, with a reported reduction in 8-hydroxydeoxyguanosine (8-OHdG) levels, a validated biomarker of oxidative DNA lesions, relative to aged neuron controls receiving no intervention. Research suggests these findings might indicate that Pinealon exerts dendritogenic and DNA-protective implications in neuronal populations exhibiting age-associated epigenetic signatures, supporting its further investigation as a research tool for studying neuroprotective mechanisms in the context of cellular aging.

 

EDR Peptide Regulation of Alzheimer’s Disease-Relevant Gene Networks

A comprehensive mechanistic review[3] analyzed the molecular and genetic dimensions of EDR’s proposed neuroprotective action in the context of Alzheimer’s disease pathogenesis. The review integrated computational modeling data, experimental in vitro observations, and pathway analysis to characterize the gene regulatory networks potentially modulated by EDR–DNA interactions.

The review proposed that EDR may regulate gene expression associated with the MAPK signaling pathway, including ERK1/2, and may support the expression of genes encoding antioxidant enzymes (SOD2, GPX1), nuclear receptors (PPARA, PPARG), and apoptotic mediators (CASP3) through direct interaction with their respective promoter sequences.

Research suggests this multi-target gene regulatory profile might confer pleiotropic neuroprotective implications in AD-relevant experimental contexts. The review further noted that molecular docking studies identified contact sites between EDR and specific hexanucleotide sequences within gene promoter regions, providing structural specificity to the proposed transcriptional regulatory mechanism.

Disclaimer: The products mentioned are not intended for human or animal consumption. Research chemicals are intended solely for laboratory experimentation and/or in-vitro testing. Bodily introduction of any sort is strictly prohibited by law. All purchases are limited to licensed researchers and/or qualified professionals. All information shared in this article is for educational purposes only.

 

References:

  1. National Center for Biotechnology Information. PubChem Compound Summary for CID 71462546, Pinealon (Glu-Asp-Arg). 2024. Available from: https://pubchem.ncbi.nlm.nih.gov/compound/71462546
  2. Khavinson VKh, Ribakova Y, Kulebiakin K, Vladychenskaya E, Kozina L, Arutjunyan A, Boldyrev A. Pinealon increases cell viability by suppression of free radical levels and activating proliferative processes. Rejuvenation Res. 2011;14(5):535-41. doi:10.1089/rej.2011.1172. PMID: 22117547. Available from: https://pubmed.ncbi.nlm.nih.gov/22117547/
  3. Khavinson V, Linkova N, Kozhevnikova E, Trofimova S. EDR Peptide: Possible Mechanism of Gene Expression and Protein Synthesis Regulation Involved in the Pathogenesis of Alzheimer’s Disease. Molecules. 2021;26(1):159. doi:10.3390/molecules26010159. PMID: 33383957. Available from: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7795577/
  4. Khavinson V, Ilina A, Kraskovskaya N, Linkova N, Cai H, Burman A, Morozov A, Tarnovskaya S, Beeraka NM. Neuroprotective Effects of Tripeptides—Epigenetic Regulators in Mouse Model of Alzheimer’s Disease. Pharmaceuticals (Basel). 2021;14(6):515. doi:10.3390/ph14060515. PMID: 34072073. Available from: https://www.mdpi.com/1424-8247/14/6/515
  5. Kraskovskaya NA, Linkova NS, Sakhenberg EI, Umnov RS, Petukhov MG, Khavinson VKh. Short Peptides Protect Fibroblast-Derived Induced Neurons from Age-Related Changes. Int J Mol Sci. 2024;25(21):11363. doi:10.3390/ijms252111363. Available from: https://pmc.ncbi.nlm.nih.gov/articles/PMC11546785/
  6. Arutjunyan A, Kozina L, Stvolinskiy S, Bulygina Y, Mashkina A, Khavinson V. Pinealon protects the rat offspring from prenatal hyperhomocysteinemia. Int J Clin Exp Med. 2012;5(2):179-85. PMID: 22567179. Available from: https://pubmed.ncbi.nlm.nih.gov/22567179/
  7. Kraskovskaya NA, Kukanova EO, Linkova NS, Korf EA, Khavinson VKh. Tripeptides Restore the Number of Neuronal Spines under Conditions of In Vitro Modeled Alzheimer’s Disease. Bull Exp Biol Med. 2017;163(6):741-744. doi:10.1007/s10517-017-3886-z. Available from: https://pubmed.ncbi.nlm.nih.gov/29038981/
  8. Mendzheritskii AM, Karantysh GV, Ryzhak GA, Dem’ianenko SV. Regulation of content of cytokines in blood serum and of caspase-3 activity in brains of old rats in model of sharp hypoxic hypoxia with Cortexin and Pinealon. Adv Gerontol. 2014;27(1):94-97. PMID: 25006604. Available from: https://pubmed.ncbi.nlm.nih.gov/25006604/
  9. Khavinson VKh, Linkova NS, Tarnovskaya SI, Diatlova AS. Short Peptides Stimulate Serotonin Expression in Cells of Brain Cortex. Bull Exp Biol Med. 2014;157(1):77-80. doi:10.1007/s10517-014-2496-y. PMID: 24824757. Available from: https://pubmed.ncbi.nlm.nih.gov/24824757/
  10. Khavinson VKh, Linkova NS, Kukanova EO, Kraskovskaya NA, Ilina A, Korf EA. Neuroprotective Effect of EDR Peptide in Mouse Model of Huntington’s Disease. J Behav Brain Sci. 2017;7:321-338. doi:10.4236/jbbs.2017.79023. Available from: https://khavinson.info/assets/files/skan/2017-khavinson_lin_kukanova.pdf
Biopeptide EL: Molecular Characterization, Elastin-Binding Receptor Dermatology, and Extracellular Matrix Research

Biopeptide EL: Molecular Characterization, Elastin-Binding Receptor Dermatology, and Extracellular Matrix Research

by | Jul 23, 2026 | Research

Biopeptide EL is the commercial designation for a synthetic lipopeptide formally classified under the INCI as Palmitoyl Hexapeptide-12. Biopeptide EL is composed of a hexapeptide sequence Val-Gly-Val-Ala-Pro-Gly (VGVAPG), covalently conjugated at its N-terminus to palmitic acid (C16:0), a 16-carbon saturated fatty acid chain. This palmitoyl conjugation confers amphiphilic character upon the molecule, yielding a lipopeptide with better-supported lipid membrane affinity relative to the unconjugated peptide.[10]

The VGVAPG hexapeptide sequence constitutes an endogenously occurring repeating motif within the hydrophobic domain of tropoelastin, the soluble precursor to elastin. This sequence is present as a repeating hexapeptide unit approximately six times within the tropoelastin polypeptide backbone, where it contributes to the characteristic spring-like elastic recoil properties of the mature elastin fiber.[1]

Research suggests that VGVAPG may function as a matrikine, a bioactive peptide fragment released upon extracellular matrix (ECM) degradation that may signal to resident dermal cells through specific cell surface receptor engagement.[6] Biopeptide EL is investigated primarily as a research tool for studying elastin-binding protein (EBP)-mediated signaling and its downstream relevance to fibroblast activity, ECM protein synthesis, and dermal structural biology.

Featured Product

Lipopeptide (Biopeptide EL) (200mg)
 

Proposed Mechanism of Action

The primary proposed receptor for Biopeptide EL’s VGVAPG sequence is the elastin-binding protein (EBP), also designated the 67 kDa elastin receptor, which is expressed on the surface of dermal fibroblasts, monocytes, and multiple other cell types.[1][4] EBP binding is proposed to initiate downstream signaling cascades that may promote elastin gene expression, fibroblast recruitment to ECM remodeling sites, and synthesis of structural ECM components including tropoelastin, fibronectin, and glycosaminoglycans (GAGs).[2][3] A secondary receptor, galectin-3, has also been identified as a VGVAPG-binding cell surface protein, potentially mediating additional ECM-interactive responses.[4]

Research suggests that EBP engagement by VGVAPG may activate the MEK/ERK signal transduction pathway, a mitogen-activated protein kinase cascade implicated in fibroblast proliferation and ECM gene regulatory responses.[4] Additionally, the EBP has been investigated in the context of vascular endothelial growth factor receptor-2 (VEGFR2) pathway cross-talk, with preclinical data suggesting that elastin receptor complex signaling may support VEGFR2 recruitment and downstream angiogenic regulatory processes.[4] The matrikine framework[6] proposed contextualizes these observations within a broader ECM-derived biological signaling model, in which proteolytic fragments of structural matrix proteins act as local regulatory molecules governing cell behavior and ECM homeostasis.

 

Scientific and Research Studies

 

VGVAPG as a Fibroblast and Monocyte Chemotaxin: Foundational Characterization

The foundational investigation[1] establishing VGVAPG’s chemotactic activity was conducted using modified Boyden chamber chemotaxis assays to evaluate fibroblast and monocyte migration in response to the isolated hexapeptide. Findings indicated that VGVAPG was chemotactic for both fibroblasts and monocytes, with optimal chemotactic activity observed at approximately 10⁻⁸ M. The magnitude of fibroblast chemotaxis toward VGVAPG was reported as approximately half to three-quarters of the maximal response elicited by platelet-derived growth factor (PDGF), a well-characterized fibroblast chemoattractant, under equivalent assay conditions.[1]

Critical specificity controls established that chemotactic responsiveness to VGVAPG was restricted to elastin-synthesizing fibroblast populations. Undifferentiated, non-elastin-producing bovine ligament fibroblasts indicated no chemotactic response to VGVAPG, whereas matrix-induced differentiation and onset of elastin synthesis were associated with acquisition of VGVAPG responsiveness.[1] Research suggests these observations might indicate that EBP expression, which is upregulated upon fibroblast differentiation, may be a prerequisite for VGVAPG-mediated chemotactic signaling. Polyclonal antibody blockade of the elastin receptor selectively mitigated both fibroblast and monocyte chemotaxis to VGVAPG, further implicating receptor-mediated specificity in the observed chemotactic responses.

 

VGVAPG-Mediated Fibroblast Proliferation and Elastin Expression: Dual Regulatory Observations

A study[2] examined the implications of elastin-derived peptides on fibroblast proliferation and ECM component synthesis in primary dermal fibroblast cultures. Exposure to VGVAPG and related elastin peptide sequences was associated with growth stimulation in fibroblast cultures, with findings suggesting that elastin-derived peptide engagement of EBP may initiate mitogenic signaling pathways in addition to chemotactic responses. Concurrent assessments of ECM component production indicated that fibroblast cultures exposed to elastin peptides may exhibit changes in collagen and related structural protein synthesis profiles, providing early data indicating multifunctional ECM regulatory activity associated with VGVAPG receptor engagement.

Complementary observations were reported by Tajima et al. (1997)[3] who examined the implications of VGVAPG on both fibroblast proliferation and elastin gene expression in dermal fibroblast cultures. The study found that while VGVAPG exposure may promote fibroblast proliferation at the cellular level, a concurrent reduction in elastin-related gene expression was observed at the molecular level. Research suggests these divergent cell-level and gene-level observations might indicate that VGVAPG’s engagement of EBP may activate distinct downstream signaling pathways governing cell proliferation and elastin gene transcription in a potentially dissociable manner. These findings may have implications for understanding the temporal and concentration-dependent regulatory dynamics of EBP-mediated signaling in ECM homeostasis research.

 

Elastin-Binding Protein Receptor Characterization and EBP Deficiency in Fibroblast Models

The structural and functional characterization of the EBP as the primary VGVAPG cell surface receptor has been a central theme in elastin peptide receptor biology. A study[5] examined EBP expression in dermal fibroblasts from subjects with systemic sclerosis, a fibrotic condition characterized by dysregulated ECM remodeling and elastin deficiency in dermal cells. Findings suggested that fibroblasts from subjects with systemic sclerosis exhibited diminished EBP expression relative to control fibroblast populations.[5]

Research suggests these observations might indicate that reduced EBP surface expression may impair fibroblast responsiveness to endogenous elastin-derived matrikines including VGVAPG, potentially contributing to dysregulated elastin synthesis and ECM homeostasis in fibrotic tissue environments. This study provides mechanistic context for the hypothesis that restoration or augmentation of EBP-mediated signaling through exogenous elastin peptide ligands such as the VGVAPG sequence in Biopeptide EL may represent a relevant investigational approach for studying ECM regulatory pathways in fibroblast research models. Additionally, experimental observations have linked EBP signaling to VEGFR2 pathway modulation, with research suggesting possible involvement of the elastin receptor complex in angiogenic regulatory networks.[4]

 

Biopeptide EL andMatrikine Signaling Concept and ECM-Derived Regulatory Biology

The broader conceptual framework within which Biopeptide EL’s VGVAPG sequence operates was formalized through the matrikine concept.[6] Research proposed that proteolytic remodeling of the ECM generates bioactive peptide fragments that may act as local autocrine and paracrine signaling molecules, regulating cell proliferation, migration, differentiation, and ECM synthesis in a manner analogous to classical growth factor signaling.[6]

VGVAPG and related elastin-derived hexapeptide sequences were identified as archetypal matrikines within this conceptual framework, given their well-characterized receptor-mediated biological activity despite being derived from a structural matrix protein generally considered biologically inert in its intact, polymerized form.

Research suggests that the matrikine signaling model might indicate a broader regulatory role for ECM-derived peptide fragments in tissue homeostasis and wound repair biology, beyond their structural functions within intact matrix polymers.[6] Within this framework, Biopeptide EL may be characterized as a synthetic matrikine-mimetic lipopeptide designed to facilitate investigation of EBP-mediated ECM signaling in controlled fibroblast research models. The matrikine concept further contextualizes observed associations between Biopeptide EL exposure and ECM component upregulation, including fibronectin and glycosaminoglycan synthesis, as downstream readouts of receptor-mediated transcriptional regulatory activity.[2]

 

Dermal Penetration and Stratum Corneum Permeation of Biopeptide EL

A dedicated permeation study[9] employed ATR-FTIR spectroscopy to monitor the penetration of Biopeptide EL into the stratum corneum and superficial epidermal layers under controlled exogenous conditions. ATR-FTIR spectroscopy enables non-invasive, depth-resolved molecular characterization of dermal layers and was applied here to track the lipopeptide’s permeation profile without biopsy or destructive sampling.

Findings suggested that Biopeptide EL permeated into the stratum corneum and epidermal layers under the conditions evaluated. Spectroscopic data were interpreted as potentially indicating that the palmitoyl group may undergo hydrolytic or enzymatic cleavage within the stratum corneum, releasing the free Hexapeptide-12 sequence for potential EBP receptor engagement within the viable epidermis and papillary dermis.[9]

Research suggests these permeation findings might indicate that lipidic conjugation of the VGVAPG sequence may serve a dual function in Biopeptide EL: supporting initial lipid barrier partitioning while potentially enabling post-penetration release of the biologically active peptide sequence. Additionally, research indicates that the concomitant interactions of Biopeptide EL with Ceramide NG (as in the Dermaxyl™ formulation) may further modulate dermal barrier function and ECM-associated hydration parameters, though the mechanistic basis of this combined interaction requires further controlled characterization.

 

Biopeptide EL and ECM Protein Synthesis: Clinical Data Summary

The clinical and applied research database for Biopeptide EL has been summarized in systematic reviews of exogenous peptides. Researchers reviewed controlled studies evaluating exogenous palmitoyl peptide formulations across multiple ECM-related endpoints. Within this literature, Biopeptide EL was characterized as an elastin-fragment-derived lipopeptide associated with stimulation of collagen, elastin, fibronectin, and glycosaminoglycan synthesis in dermal fibroblast-based research models.

A double-blind, placebo-controlled assessment involving subjects applying an emulsion containing Biopeptide EL twice daily over a one-month period was referenced within this review framework. Findings suggested support for dermal elasticity and firmness parameters relative to placebo-treated murine models.

Research suggests these observations might indicate that EBP-mediated ECM signaling activation by the VGVAPG sequence in Biopeptide EL may translate into measurable structural dermal endpoints under controlled interactive conditions. However, the methodological detail available from supplier-originated studies limits independent mechanistic interpretation.

Gorouhi and Maibach (2009)[7] similarly reviewed the data for exogenous peptides in mammalian dermatological studies, noting that palmitoyl conjugation represents an established delivery support strategy for ECM-regulatory hexapeptide sequences including those derived from elastin hydrophobic domain repeats.

Disclaimer: The products mentioned are not intended for human or animal consumption. Research chemicals are intended solely for laboratory experimentation and/or in-vitro testing. Bodily introduction of any sort is strictly prohibited by law. All purchases are limited to licensed researchers and/or qualified professionals. All information shared in this article is for educational purposes only.

 

References:

  1. Senior RM, Griffin GL, Mecham RP, Wrenn DS, Prasad KU, Urry DW. Val-Gly-Val-Ala-Pro-Gly, a repeating peptide in elastin, is chemotactic for fibroblasts and monocytes. J Cell Biol. 1984;99(3):870-874. doi:10.1083/jcb.99.3.870. PMID: 6547961. PMCID: PMC2113419. Available from: https://rupress.org/jcb/article-abstract/99/3/870/21063/
  2. Kamoun A, Landeau JM, Godeau G, Wallach J, Duchesnay A, Pellat B, Hornebeck W. Growth stimulation of human skin fibroblasts by elastin-derived peptides. Cell Adhes Commun. 1995;3(4):273-281. doi:10.3109/15419069509081013. Available from: https://pubmed.ncbi.nlm.nih.gov/8640747/
  3. Tajima S, Wachi H, Uemura Y, Okamoto K. Modulation by elastin peptide VGVAPG of cell proliferation and elastin expression in skin fibroblasts. Arch Dermatol Res. 1997;289(8):489-492. doi:10.1007/s004030050227. PMID: 9266029. Available from: https://pubmed.ncbi.nlm.nih.gov/9266029/
  4. Scandolera A, Odoul L, Salvi A, Dambroise E, Maurissen L, Thomassin L, et al. The Elastin Receptor Complex Controls Blood Vessel Formation by Recruiting VEGFR2 and Regulating Its Signaling. J Invest Dermatol. 2016;136(8):1688-1697. doi:10.1016/j.jid.2016.04.009. PMID: 27108726. Available from: https://pubmed.ncbi.nlm.nih.gov/27108726/
  5. Bielecki M, Kowal K, Lapinska A, Pietrowska J, Chyczewski L, Kowal-Bielecka O. Diminished expression of elastin-binding protein in dermal fibroblasts as a possible cause of elastin defect in patients with systemic sclerosis. J Rheumatol. 2008;35(10):2042-2050. PMID: 18821746. Available from: https://pubmed.ncbi.nlm.nih.gov/18821746/
  6. Maquart FX, Siméon A, Pasco S, Monboisse JC. Regulation of cell activity by the extracellular matrix: the concept of matrikines. J Soc Biol. 1999;193(4-5):423-428. PMID: 10615253. Available from: https://pubmed.ncbi.nlm.nih.gov/10615253/
  7. Gorouhi F, Maibach HI. Role of topical peptides in preventing or treating aged skin. Int J Cosmet Sci. 2009;31(5):327-345. doi:10.1111/j.1468-2494.2009.00490.x. PMID: 19570099. Available from: https://pubmed.ncbi.nlm.nih.gov/19570099/
  8. Schagen SK. Topical Peptide Treatments with Effective Anti-Aging Results. Cosmetics. 2017;4(2):16. doi:10.3390/cosmetics4020016. Available from: https://www.mdpi.com/2079-9284/4/2/16
  9. Ockermann T, Schrage A, Nevoigt E, Eckert RL, Hensen H, Grether-Beck S, Krisch B, Krutmann J. Noninvasive Monitoring of Palmitoyl Hexapeptide-12 (Biopeptide EL) Penetration into the Stratum Corneum by Attenuated Total Reflectance-Fourier Transform Infrared Spectroscopy. Skin Pharmacol Physiol. 2011;24(4):202-212. doi:10.1159/000321082. Available from: https://pubmed.ncbi.nlm.nih.gov/21252463/
  10. National Center for Biotechnology Information. PubChem Compound Summary for CID 15985226, Palmitoyl Hexapeptide-12. 2024. Available from: https://pubchem.ncbi.nlm.nih.gov/compound/Palmitoyl-hexapeptide-12
BPC157: Molecular Characterization, Pleiotropic Signaling Mechanisms, and Preclinical Research

BPC157: Molecular Characterization, Pleiotropic Signaling Mechanisms, and Preclinical Research

by | Jul 14, 2026 | Research

Body Protection Compound-157 (BPC157) is a synthetic pentadecapeptide composed of 15 amino acids. It is derived from a partial sequence of a gastric protective protein identified in gastric juice.[9] The complete amino acid sequence of BPC157 is Gly-Glu-Pro-Pro-Pro-Gly-Lys-Pro-Ala-Asp-Asp-Ala-Gly-Leu-Val. BPC157 has a molecular formula of C₆₂H₉₈N₁₆O₁₂ and a molecular weight of approximately 1419.5 g/mol (PubChem CID 107842122). The peptide is characterized by its stability in gastric juice, which distinguishes it from many other peptide research compounds and has informed its investigation across gastrointestinal and systemic research contexts.[2]

Research suggests BPC157 may function through multiple, overlapping intracellular signaling pathways, engaging growth factor receptor networks, nitric oxide biosynthesis cascades, cytoskeletal regulatory mechanisms, and neurotransmitter-modulatory systems.[3] The peptide’s pleiotropic activity profile across diverse tissue and organ systems has positioned it as a broadly investigated investigational tool in preclinical research, with documented observations across musculoskeletal, gastrointestinal, vascular, and neurological implications relevant to murine research models.[2]

Featured Product

BPC-157
 

Molecular Characterization and Essential Functions

BPC157 is distinguished among synthetic research peptides by its resistance to enzymatic degradation in gastric environments, a property attributed to its partial origin from an endogenous gastric protein sequence.[2] This stability may support sustained biological activity across laboratory settings in which many shorter synthetic peptides would undergo rapid proteolytic degradation.

The peptide’s principal proposed functions encompass: modulation of vascular endothelial growth factor receptor-2 (VEGFR2)-mediated angiogenic signaling; activation of endothelial nitric oxide synthase (eNOS) through the Akt kinase axis; regulation of focal adhesion kinase (FAK) and paxillin-associated cytoskeletal remodeling pathways; upregulation of growth hormone receptor expression in fibroblast populations; and engagement of dopaminergic, serotonergic, and GABAergic neurotransmitter systems within central nervous system research models.[3][5][7]

Research suggests that these overlapping mechanisms may enable BPC157 to support tissue repair, vascular homeostasis, inflammatory regulation, and neuromodulatory signaling in a pleiotropic and context-dependent manner.

 

Scientific and Research Studies

 

BPC157 and Tendon Fibroblast Signaling: PAK-Paxillin Pathway Modulation

A controlled in vitro investigation by Chang et al. (2011)[1] evaluated the implications of BPC157 on tendon-derived fibroblasts isolated from murine Achilles tendon tissue. Cells were maintained under standard culture conditions and compared with parallel BPC157-exposed cultures. Morphological assessments indicate alterations in fibroblast spatial organization and expansion patterns in peptide-exposed groups, suggesting potential regulatory implications of cytoskeletal organization associated with tendon matrix structuring.

Oxidative stress was introduced using hydrogen peroxide to simulate reactive cellular environments. Fibroblasts exposed to BPC157 under these conditions exhibited greater survival indices relative to controls, potentially indicating involvement in cellular stress response modulation. Migration assay data further suggested better-supported cellular motility in peptide-exposed cultures, a process linked to cytoskeletal dynamics and focal adhesion regulation.

Immunoblot analyses revealed increased phosphorylation of p21-activated kinase (PAK) and paxillin following BPC157 exposure, with total protein levels remaining comparatively stable.[1] Research suggests these findings might indicate that BPC157 supports tendon fibroblast signaling primarily through post-translational modulation of FAK-paxillin-associated pathways governing F-actin assembly, cellular adhesion, and directional migration.

 

Growth Hormone Receptor Upregulation in Fibroblast Populations

An investigation[6] examined the implications of BPC157 on gene expression profiles in Achilles tendon fibroblast cultures using cDNA microarray analysis. Among the genes most substantially upregulated by BPC157 exposure was the growth hormone receptor (GHR), identified as one of the most abundantly induced transcripts across the experimental gene expression dataset.

Time-dependency increases in GHR expression were confirmed at both mRNA and protein levels by RT-PCR and Western blot analyses, respectively. Subsequent exposure of BPC157-exposed fibroblasts to growth hormone produced time-dependent increases in cellular proliferation, quantified by MTT assay and PCNA expression analysis.

Janus kinase 2 (JAK2), a downstream effector of GHR signaling, was activated in a time-dependent manner following combined BPC157 and growth hormone stimulation.[6] Research suggests these findings might indicate that BPC157 may potentiate fibroblast responsiveness to growth hormone through GHR upregulation, representing a potential secondary anabolic mechanism contributing to observed tissue repair-associated implications in musculoskeletal research models.

 

BPC157 and VEGFR2-Mediated Angiogenic Signaling

The pro-angiogenic properties of BPC157 and their mechanistic basis were characterized in a study by Hsieh et al. (2017)[5] which examined VEGFR2 expression and activation across endothelial cell culture systems and preclinical tissue injury models. Findings suggested that BPC157 exposure was associated with upregulation of VEGFR2 at both mRNA and protein levels, and with downstream activation of the phosphatidylinositol 3-kinase (PI3K)-Akt-eNOS signaling cascade.

Research suggests that Akt-mediated eNOS phosphorylation may increase nitric oxide (NO) bioavailability within vascular tissue microenvironments, potentially supporting vasodilation, microvascular integrity, and organized angiogenic responses in tissues with limited baseline vascular supply such as tendon, ligament, and fibrocartilaginous structures. ⁵

A VEGF-independent pathway involving Src kinase and caveolin-1-mediated eNOS activation was additionally proposed as a parallel angiogenic mechanism engaged by BPC157. Research suggests these dual angiogenic signaling routes might indicate that BPC157 engages overlapping vascular regulatory mechanisms, potentially enabling angiogenic responses across tissue environments with differing baseline growth factor availability.

 

BPC157 in Gastrointestinal Mucosal and Systemic Cytoprotection Models

A foundational body of research[10] has characterized BPC157’s cytoprotective activity across a range of gastrointestinal and systemic injury models. Preclinical investigations encompassing ethanol-induced gastric mucosal lesions, NSAID-mediated ulceration, cysteamine-induced duodenal injury, and inflammatory bowel disease analogues have reported associations between BPC157 exposure and reductions in mucosal lesion surface area, preservation of submucosal vascular architecture, and modulation of mucosal structural integrity.[2]

BPC157’s interactions with the NO system have been proposed as a central mechanistic contributor to its gastrointestinal cytoprotective profile, with research suggesting potential upregulation of eNOS expression and modulation of NO bioavailability within gastric mucosal microcirculation.[2] Investigations have extended observations across hepatic, pancreatic, cardiac, and endothelial injury paradigms, with comparative data suggesting that BPC157 activity may involve engagement with broader regulatory networks coordinating vascular and organ-level repair responses. Research suggests these multi-organ observations might indicate systemic cytoprotective signaling engagement rather than tissue-localized activity restricted to the gastrointestinal compartment.

 

Musculoskeletal Tissue Repair: Narrative Review Data (2025)

A 2025 narrative synthesized preclinical data on BPC157’s mechanisms and implications across musculoskeletal tissue repair research contexts. The review characterized BPC157 as activating multiple overlapping signaling pathways, notably VEGFR2-mediated angiogenesis via the PI3K-Akt-eNOS axis, FAK-paxillin-driven fibroblast migration and adhesion, ERK1/2-mediated endothelial and muscle cell repair signaling, and GHR upregulation in fibroblast populations.

The review reported that preclinical models involving surgically transected tendons, ligaments, and bone structures consistently reported associations between BPC157 exposure and accelerated structural repair, better-supported biomechanical strength indices, and better-supported collagen matrix organization.

Poorly vascularized tissues including tendons and myotendinous junctions were highlighted as particularly relevant research contexts, given that BPC157’s proposed pro-angiogenic mechanisms may provide organized vascular ingrowth to tissues with inherently limited baseline blood supply. Research suggests these synthesized findings might indicate that VEGFR2 and eNOS pathway activation by BPC157 may represent mechanistically coherent contributors to observed musculoskeletal repair-associated outcomes across diverse preclinical tissue models.

 

BPC157 and Neurotransmitter System Modulation: Brain-Gut Axis Research

Research into the central nervous system implications of BPC157 has characterized potential interactions with dopaminergic, serotonergic, GABAergic, and opioid neurotransmitter systems across preclinical behavioral and neurobiological research paradigms relevant to murine models. A seminal review[3] conceptualized BPC157’s neurological activity within a brain-gut axis framework, proposing that peripheral BPC157 exposure may produce centrally detectable implications through gut-brain signaling interconnections and direct neuromodulatory engagement.

Autoradiographic measurements of regional brain serotonin synthesis following systemic BPC157 exposure indicated time-dependent and brain region-specific changes in serotonergic activity, with substantia nigra and nucleus accumbens among the regions exhibiting altered synthesis patterns.[3] Concurrent observations suggested modulation of dopaminergic system function, with BPC157 reported to attenuate disturbances in dopaminergic signaling associated with neuroleptic exposure and amphetamine challenge in murine models.[3]

Research suggests these neurotransmitter-modulatory observations might indicate that BPC157 engages multiple monoaminergic and GABAergic regulatory systems simultaneously, potentially accounting for the range of behavioral implications, including anxiolytic and neuroprotective profiles reported across murine models.

 

BPC157 as a Putative Neurotransmitter-Like Cytoprotective Mediator

A comprehensive study[7] proposed a conceptual framework characterizing BPC157 as a cytoprotection mediator with neurotransmitter-like activity. The review synthesized data supporting BPC157’s endogenous stability in gastric juice and its capacity to produce consistent relevant implications across diverse mammalian research models regardless of experimental route, a property the authors proposed might indicate an endogenous cytoprotective regulatory function analogous to neurotransmitter signaling at the gastrointestinal and systemic level.

The review documented BPC157-associated modulation of dopaminergic, serotonergic, GABAergic, and glutamatergic signaling systems, alongside interactions with NO pathways and prostaglandin cascades. Neuroprotective observations included attenuation of traumatic brain injury-associated progression, spinal cord compression injury outcomes, and encephalopathy-associated changes in murine models.

Research suggests these multi-system neuromodulatory findings might indicate that BPC157 engages interconnected regulatory pathways spanning both peripheral cytoprotective and central neurotransmitter-associated biological mechanisms, warranting further characterization across targeted mechanistic research frameworks.

 

Central Nervous System Repair: Neuroregeneration Research

A 2022 review[11] examined BPC157’s interactions with central and peripheral nervous system repair pathways across preclinical neurobiological research models. Observations reviewed encompassed somatosensory neuron protection, peripheral nerve regeneration, attenuation of traumatic brain injury-associated pathological progression, and functional recovery in spinal cord compression models exhibiting axonal necrosis, demyelination, and cyst formation.

The review further characterized BPC157’s modulation of dopaminergic and serotonergic neurotransmitter systems in the context of central nervous system regulatory biology, proposing mechanistic connections between peripheral peptide signaling and centrally observed neuroprotective and neuroregenerative outcomes.

Research suggests these neurological findings might indicate that BPC157 engages multi-level regulatory interactions between gut-derived peptide signaling and central nervous system maintenance pathways, supporting its relevance as a research tool for investigating peptide-mediated neurobiological mechanisms across diverse central and peripheral nervous system research contexts.

Disclaimer: The products mentioned are not intended for human or animal consumption. Research chemicals are intended solely for laboratory experimentation and/or in-vitro testing. Bodily introduction of any sort is strictly prohibited by law. All purchases are limited to licensed researchers and/or qualified professionals. All information shared in this article is for educational purposes only.

 

References:

  1. Chang CH, Tsai WC, Liu HT, Wang J, Mandal M, et al. The promoting effect of pentadecapeptide BPC 157 on tendon healing involves tendon outgrowth, cell survival, and cell migration. J Appl Physiol. 2011;110(3):774-80. doi:10.1152/japplphysiol.00945.2010. PMID: 21030672. Available from: https://pubmed.ncbi.nlm.nih.gov/21030672/
  2. Sikiric P, Seiwerth S, Rucman R, et al. Stable gastric pentadecapeptide BPC 157: novel therapy in gastrointestinal tract. Curr Pharm Des. 2011;17(16):1612-32. doi:10.2174/138161211796196954. PMID: 21548867. Available from: https://pubmed.ncbi.nlm.nih.gov/21548867/
  3. Sikiric P, Seiwerth S, Rucman R, et al. Brain-gut Axis and Pentadecapeptide BPC 157: Theoretical and Practical Implications. Curr Neuropharmacol. 2016;14(8):857-865. doi:10.2174/1570159X13666160502153022. PMID: 27138887. PMCID: PMC5333585. Available from: https://pmc.ncbi.nlm.nih.gov/articles/PMC5333585/
  4. Chang CH, Tsai WC, Lin MS, Hsu YH, Pang JHS. The promoting effect of pentadecapeptide BPC 157 on tendon healing involves tendon outgrowth, cell survival, and cell migration. Growth Horm IGF Res. 2011. doi:10.1007/s12020-011-9505-2. Available from: https://pubmed.ncbi.nlm.nih.gov/21030672/
  5. Hsieh MJ, Liu HT, Wang CN, Huang HY, Lin Y, Ko YS, Wang JS, Chang VH, Pang JS. Therapeutic potential of pro-angiogenic BPC157 is associated with VEGFR2 activation and up-regulation. J Mol Med (Berl). 2017;95(3):323-333. doi:10.1007/s00109-016-1488-y. PMID: 27889809. Available from: https://pubmed.ncbi.nlm.nih.gov/27889809/
  6. Chang CH, Tsai WC, Hsu YH, Pang JHS. Pentadecapeptide BPC 157 enhances the growth hormone receptor expression in tendon fibroblasts. Molecules. 2018;23(12):3153. doi:10.3390/molecules23123153. PMID: 30486346. PMCID: PMC6271067. Available from: https://pmc.ncbi.nlm.nih.gov/articles/PMC6271067/
  7. Sikiric P, Seiwerth S, Rucman R, et al. The stable gastric pentadecapeptide BPC 157 pleiotropic beneficial activity and its possible relations with neurotransmitter activity. Pharmaceuticals (Basel). 2024;17(4):461. doi:10.3390/ph17040461. PMID: 38675422. PMCID: PMC11053547. Available from: https://pmc.ncbi.nlm.nih.gov/articles/PMC11053547/
  8. McGuire FP, Martinez R, Lenz A, Skinner L, Cushman DM. Regeneration or Risk? A Narrative Review of BPC157 for Musculoskeletal Healing. Curr Rev Musculoskelet Med. 2025;18(12):611-619. doi:10.1007/s12178-025-09990-7. PMID: 40789979. PMCID: PMC12446177. Available from: https://pmc.ncbi.nlm.nih.gov/articles/PMC12446177/
  9. National Center for Biotechnology Information. PubChem Compound Summary for CID 107842122, BPC157. 2024. Available from: https://pubchem.ncbi.nlm.nih.gov/compound/BPC157
  10. Sikiric P, Seiwerth S, Rucman R, et al. Toxicity by NSAIDs. Counteraction by stable gastric pentadecapeptide BPC 157. Curr Pharm Des. 2013;19(1):76-83. PMID: 22950513. Available from: https://pubmed.ncbi.nlm.nih.gov/22950513/
  11. Vukojevic J, Milavic M, Perovic D, Ilic S, Cilic AZ, Duran N, et al. Pentadecapeptide BPC 157 and the central nervous system. Neural Regen Res. 2022;17(3):482-487. doi:10.4103/1673-5374.320969. PMID: 34380878. Available from: https://pubmed.ncbi.nlm.nih.gov/34380878/

 

Copper Peptides: Molecular Characterization, Mechanistic Biology, and Emerging Research

Copper Peptides: Molecular Characterization, Mechanistic Biology, and Emerging Research

by | Jul 10, 2026 | Research

Copper peptides are a class of naturally occurring and synthetically reproduced small peptide and copper ion complexes in which Cu²⁺ coordinates with specific amino acid sequences to form stable chelate structures. Three members of this class have received the most extensive research attention: glycyl-L-histidyl-L-lysine copper(II) (GHK-Cu), aspartyl-alanyl-histidyl-lysine copper(II) (DAHK-Cu), and alanyl-histidyl-lysine copper(II) (AHK-Cu). Each exhibits a distinct coordination chemistry, tissue distribution, and functional profile in preclinical research models.[1][2][4]

GHK-Cu is the most extensively characterized member of this class. It is a tripeptide originally isolated from plasma albumin fractions and subsequently detected in saliva, urine, and wound fluid.[11][6] Research has attributed broad biological activity to GHK-Cu, encompassing extracellular matrix (ECM) remodelling, gene expression modulation, antioxidant pathway activation, wound repair facilitation, and neuromodulatory effects in preclinical models.[13]

DAHK-Cu is a tetrapeptide corresponding to the N-terminal copper-binding domain of serum albumin, studied principally for its role in copper(II) transport, redox regulation, and neuroprotective signalling.[2] AHK-Cu (PubChem CID 168431292) is a tripeptide investigated for its capacity to stimulate dermal fibroblast activity, modulate growth factor expression, and influence follicular biology.[4][13]

Featured Product

GHK-CU (Copper) Peptide (50mg)
 

Copper Peptides Historical Development

GHK-Cu was first isolated in 1973 by Pickart and Thayer, who identified a plasma albumin-derived tripeptide fraction capable of stimulating protein synthesis in aged liver tissue to levels characteristic of younger tissue.[1] This seminal observation established the conceptual basis for GHK-Cu as a biological signalling molecule associated with tissue maintenance and cellular rejuvenation. Subsequent characterization confirmed GHK’s high affinity for cupric ions (Cu²⁺), and the resulting copper complex (GHK-Cu) was found to be the biologically active species.¹ Research suggests that plasma GHK-Cu concentrations may decline over time from approximately 200 ng/mL in the first 25% of life to approximately 80 ng/mL by the 70%, a trajectory that might suggest a functional association between GHK-Cu availability and time-related tissue repair capacity.[1]

Interest in the broader copper peptide class subsequently expanded. DAHK-Cu was identified as the N-terminal copper-binding sequence of serum albumin and investigated computationally and biochemically for its coordination geometry and redox properties.[2] AHK-Cu emerged from applied research into dermatological active ingredients, with preclinical investigations examining its effects on fibroblast proliferation and hair follicle biology.[4][13]

Early cellular biology investigations in the 1980s established that GHK-Cu could stimulate collagen synthesis in fibroblast cultures and subsequent decades of research extended the characterization of this class into wound repair, oncological, neurological, pulmonary, and skin biology research contexts.

 

Copper Peptides Coordination Chemistry and Proposed Mechanisms of Action

The biological activity of copper peptides is thought to arise primarily from their ability to coordinate and mobilize Cu²⁺ ions within the extracellular environment, modulating intracellular signalling cascades through copper-dependent enzymatic and transcriptional pathways.[13]

GHK-Cu coordinates Cu²⁺ through the imidazole nitrogen of the histidine residue, the terminal α-amino group, and deprotonated amide nitrogen atoms of the peptide backbone, forming a square-planar chelate geometry. This geometry is thought to influence the redox state of coordinated copper, potentially enabling participation in both oxidative and reductive cellular reactions.[1]

Research suggests DAHK-Cu exhibits distinct coordination behaviour attributable to the aspartyl residue at its N-terminus, which may contribute to carboxylate-mediated chelation alongside histidine imidazole coordination.[2] Computational modelling suggests DAHK-Cu may adopt multiple stable copper-binding configurations, with relative stability influenced by solvent environment and pH. These properties position DAHK-Cu as a potentially relevant species in albumin-mediated copper transport and in redox biology research contexts.

AHK-Cu has been investigated for its potential to modulate vascular endothelial growth factor (VEGF) and TGF-β1 expression in fibroblast and endothelial cell cultures, with research suggesting potential regulatory roles in angiogenesis and ECM remodelling.[4]

 

Copper Peptides Scientific and Research Studies

 

GHK-Cu and Extracellular Matrix Biology: Collagen Synthesis and Matrix Metalloproteinase Regulation

Foundational research by Maquart et al. (1988)[5] characterized the perceived effects of GHK-Cu on collagen synthesis in primary fibroblast cultures. GHK-Cu exposure at nanomolar concentrations was associated with measurable increases in collagen production relative to untreated control cultures, establishing a precedent for the peptide’s potential role as a fibroblast-activating signal. These early observations prompted investigation into the ECM regulatory mechanisms through which GHK-Cu might exert its effects.

Subsequent investigations by Siméon et al. (2000)[6] extended this characterization to matrix metalloproteinase (MMP) biology. GHK-Cu exposure in fibroblast cultures was associated with elevated matrix metalloproteinase-2 (MMP-2) expression, alongside concurrent up-regulation of tissue inhibitors of metalloproteinases-1 and -2 (TIMP-1 and TIMP-2). Research suggests this dual regulatory pattern appear to show that GHK-Cu participates in a coordinated ECM remodelling response, in which controlled MMP-mediated matrix degradation is balanced by TIMP-mediated inhibition to preserve matrix structural integrity. These findings may inform the study of age-related changes in ECM homeostasis and wound-associated tissue remodelling processes.[6]
 

GHK-Cu and Wound Repair: Comparative Preclinical Models

A controlled study by Cangul et al. (2006)[7] evaluated GHK-Cu against zinc oxide in a standardized open-wound model using 18 New Zealand White rabbits divided into three groups: GHK-Cu, zinc oxide, and placebo. Wound assessments were conducted over a 21-day period following standardized wound induction. The investigators reported that the GHK-Cu group exhibited significantly greater mean wound contraction relative to both the zinc oxide and placebo groups, and concluded that the tripeptide-copper complex may represent a more effective choice within wound care research protocols compared to zinc oxide under the conditions studied.[7]

A follow-up investigation by Gul et al. (2008)[8] compared GHK-Cu with helium-neon laser therapy at energy levels of 1 J/cm² and 3 J/cm² across 24 New Zealand White rabbits over a 28-day wound monitoring period. Post-experimental histological analysis suggest that subjects receiving GHK-Cu exhibited reduced neutrophil infiltration indicative of attenuated inflammatory response and increased neovascularization, potentially reflecting accelerated tissue regeneration. Research suggests these findings might suggest complementary anti-inflammatory and pro-angiogenic properties of GHK-Cu in wound repair contexts.[8]

 

GHK-Cu in Neuropathic Ulcer Models

A controlled trial by Mulder et al. (1994)[9] evaluated GHK-Cu peptide complex gel in subjects with neuropathic plantar ulcers, employing a randomized placebo-controlled design with a standardized sharp debridement protocol. Subjects allocated to the GHK-Cu gel group exhibited wound closure rates exceedingly high, compared to relatively lower rate in the placebo control group.9] Research suggests these findings might show that GHK-Cu engagement of tissue remodelling and cellular regeneration pathways may produce measurable improvements in wound resolution relative to standard care in neuropathic ulcer models.

 

GHK-Cu and GHK-Cu-Loaded Biomaterial Dressings: Wound Healing Research

A recent investigation by Wang et al. (2024)[15] developed and evaluated an electrospun GHK-Cu/pionin-loaded polyvinyl butyral/polyvinylpyrrolidone (PVB/PVP) smart wound dressing in a controlled wound healing model. The composite dressing was designed to enable controlled release of GHK-Cu from a fibrous scaffold matrix. Outcomes assessed included oxidative stress markers, inflammatory cytokine profiles, antimicrobial activity, and tissue regenerative endpoints across wound closure assessments.[15]

Research suggests that the GHK-Cu-loaded composite dressing was associated with accelerated wound closure, reduced pro-inflammatory cytokine expression, decreased oxidative stress markers, and enhanced tissue regeneration relative to control dressings. The investigators proposed that GHK-Cu’s anti-oxidant, anti-inflammatory, and ECM-modulatory properties may be delivered in a sustained, localized manner through electrospun scaffold integration. Research suggests these findings suggest that GHK-Cu-functionalized biomaterial platforms could represent a relevant direction for investigating advanced wound care systems in preclinical models.

 

GHK-Cu and Antioxidant and Anti-inflammatory Signalling in Pulmonary Models

Research by Zhang et al. (2022)[10] examined the potential of GHK-Cu in murine models exposed to cigarette smoke (CS), evaluating pro-inflammatory cytokine expression, neutrophil-mediated inflammatory indices, and oxidative stress biomarkers in pulmonary tissue. Findings appear to show that GHK-Cu exposure was associated with reductions in bronchoalveolar lavage concentrations of interleukin-1β (IL-1β) and tumour necrosis factor-α (TNF-α), and with attenuation of myeloperoxidase (MPO) activity in lung tissue.[10]

 

GHK-Cu and Neuromodulatory Biology: Anxiety, Aggression, and Pain

Preclinical behavioural investigations have explored the neuromodulatory properties of GHK-Cu across multiple experimental paradigms. Bobyntsev et al. (2015)[11] evaluated any anxiolytic effects using an elevated plus maze model in rodents, a validated paradigm in which increased open-arm exploration reflects reduced anxiety-like behaviour. GHK-Cu-exposed animals reportedly exhibited significant changes in anxiety-related behavioural measures relative to untreated controls, with the pattern of results interpreted as potentially consistent with anxiolytic activity.[11]

Another research[12] examined GHK effects on pain-induced aggressive-defensive behaviour in a rodent model employing mild electrical stimulation to provoke aggression between paired animals. Exposure to the Gly-His-Lys peptide sequence 12 minutes prior to stimulation was associated with an approximately fivefold reduction in aggressive interaction frequency relative to untreated controls.[12] Research suggests these observations speculate that GHK-Cu may modulate stress-induced behavioural responses through neuromodulatory mechanisms, though the specific receptor and signalling pathways underlying these preclinical findings warrant further mechanistic characterization.

 

GHK-Cu and Cognitive Resilience in Aged Animal Models

A recent preprint investigation by Tucker et al. (2023)[14] examined the potential of intranasal GHK-Cu on cognitive performance and neuroinflammatory markers in aged C57BL/6 mice at 20 months of age. The experimental model involved twice-daily intranasal GHK-Cu exposure over a two-month period, with cognitive performance evaluated using spatial memory and learning navigation tasks, and neurobiological outcomes assessed through markers of neuroinflammation and axonal integrity.

Findings suggested that aged mice receiving GHK-Cu exhibited enhanced cognitive performance in spatial memory and learning navigation tasks relative to saline-treated controls. Additionally, neuroinflammatory marker expression and axonal damage indices were reduced in GHK-Cu-treated animals compared to controls.[14] Research suggests these preliminary observations might suggest that GHK-Cu engagement of antioxidant and anti-inflammatory pathways may extend to the central nervous system, and that copper peptide signalling could represent a relevant target for investigating age-associated cognitive decline in preclinical models. The authors note that further peer-reviewed investigation is warranted to confirm and extend these findings.

 

AHK-Cu: Dermal Fibroblast Activation, Collagen Synthesis, and Hair Follicle Biology

AHK-Cu has been investigated in dermatological and follicular biology research contexts. Preclinical data reviewed by Patt et al.[4] suggest that AHK-Cu may stimulate collagen synthesis in dermal fibroblast models, with observed increases in collagen and elastin production associated with enhanced dermal matrix density in animal models. The proposed mechanism involves AHK-Cu-mediated modulation of VEGF and TGF-β1 expression, with downstream activation of both fibroblasts which produce structural matrix proteins and endothelial cells, which support vascular network formation in regenerating tissue.[4]

 

DAHK-Cu: Computational Characterization and Redox Biology

Milner et al. (2021)² conducted a computational study of copper binding to the DAHK tetrapeptide using molecular modelling approaches to characterize the coordination geometry, binding energy landscape, and electronic properties of the DAHK-Cu complex. Findings reportedly suggest that DAHK may adopt multiple stable Cu²⁺ coordination configurations, with the aspartyl carboxylate and histidyl imidazole residues contributing to a flexible multi-dentate coordination environment.² Research suggests these computational findings might suggest that DAHK-Cu’s structural flexibility could enable dynamic participation in copper ion transport and redox cycling processes in albumin-mediated copper homeostasis, with potential implications for the study of copper dysregulation in oxidative stress and neurodegenerative research contexts.

Disclaimer: The products mentioned are not intended for human or animal consumption. Research chemicals are intended solely for laboratory experimentation and/or in-vitro testing. Bodily introduction of any sort is strictly prohibited by law. All purchases are limited to licensed researchers and/or qualified professionals. All information shared in this article is for educational purposes only.

 

References:

  1. Pickart L, Margolina A. Regenerative and Protective Actions of the GHK-Cu Peptide in the Light of the New Gene Data. Int J Mol Sci. 2018;19(7):1987. doi:10.3390/ijms19071987. PMID: 29986520. Available from: https://pmc.ncbi.nlm.nih.gov/articles/PMC6073405/
  2. Milner A, Alshammari N, Platts JA. Computational study of copper binding to DAHK peptide. Inorganica Chimica Acta. 2021;528:120589. doi:10.1016/j.ica.2021.120589. Available from: https://doi.org/10.1016/j.ica.2021.120589
  3. Pickart L, Vasquez-Soltero JM, Margolina A. GHK and DNA: resetting the human genome to health. Biomed Res Int. 2014;2014:151479. doi:10.1155/2014/151479. PMID: 25302294. Available from: https://pubmed.ncbi.nlm.nih.gov/25302294/
  4. Patt LM. Neova DNA Repair Factor Nourishing Lotion Stimulates Collagen and Speeds Natural Repair Process. Procyte/Neova Clinical Study Report. Available from: https://www.dermacaredirect.co.uk/skin/frontend/default/dermacare/pdf/neova-dna-nourishing-study.pdf
  5. Maquart FX, Pickart L, Laurent M, Gillery P, Monboisse JC, Borel JP. Stimulation of collagen synthesis in fibroblast cultures by the tripeptide-copper complex glycyl-L-histidyl-L-lysine-Cu2+. FEBS Lett. 1988;238(2):343-6. doi:10.1016/0014-5793(88)80509-x. PMID: 3169264. Available from: https://pubmed.ncbi.nlm.nih.gov/3169264/
  6. Siméon 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):2257-65. doi:10.1016/s0024-3205(00)00803-1. PMID: 11045606. Available from: https://pubmed.ncbi.nlm.nih.gov/11045606/
  7. Cangul IT, Gul NY, Topal A, Yilmaz R. Evaluation of the effects of tripeptide-copper complex and zinc oxide on open-wound healing in rabbits. Vet Dermatol. 2006;17(6):417-23. doi:10.1111/j.1365-3164.2006.00551.x. PMID: 17083573. Available from: https://pubmed.ncbi.nlm.nih.gov/17083573/
  8. Gul NY, Topal A, Cangul IT, Yanik K. The effects of tripeptide copper complex and helium-neon laser on wound healing in rabbits. Vet Dermatol. 2008;19(1):7-14. doi:10.1111/j.1365-3164.2007.00647.x. PMID: 18177285. Available from: https://pubmed.ncbi.nlm.nih.gov/18177285/
  9. Mulder GD, Patt LM, Sanders L, Rosenstock J, Altman MI, Hanley ME, Duncan GW. Enhanced healing of ulcers in patients with diabetes by treatment with glycyl-l-histidyl-l-lysine copper. Wound Repair Regen. 1994;2(4):259-69. doi:10.1046/j.1524-475X.1994.20406.x. PMID: 17147644. Available from: https://pubmed.ncbi.nlm.nih.gov/17147644/
  10. Zhang Q, Yan L, Lu J, Zhou X. Glycyl-L-histidyl-L-lysine-Cu2+ attenuates cigarette smoke-induced pulmonary emphysema and inflammation by reducing oxidative stress pathway. Front Mol Biosci. 2022;9:925700. doi:10.3389/fmolb.2022.925700. Available from: https://doi.org/10.3389/fmolb.2022.925700
  11. Bobyntsev II, Chernysheva OI, Dolgintsev ME, Smakhtin MY, Belykh AE. Anxiolytic effects of Gly-His-Lys peptide and its analogs. Bull Exp Biol Med. 2015;158(6):726-8. doi:10.1007/s10517-015-2847-3. PMID: 25900608. Available from: https://pubmed.ncbi.nlm.nih.gov/25900608/
  12. Sever’yanova LA, Dolgintsev ME. Effects of Tripeptide Gly-His-Lys in Pain-Induced Aggressive-Defensive Behavior in Rats. Bull Exp Biol Med. 2017;164(2):140-143. doi:10.1007/s10517-017-3943-3. PMID: 29181666. Available from: https://pubmed.ncbi.nlm.nih.gov/29181666/
  13. Pyo HK, Yoo HG, Won CH, Lee SH, Kang YJ, Eun HC, Cho KH, Kim KH. The effect of tripeptide-copper complex on hair growth in vitro. Arch Pharm Res. 2007;30(7):834-9. doi:10.1007/BF02978833. PMID: 17703734. Available from: https://pubmed.ncbi.nlm.nih.gov/17703734/
  14. Tucker M, Keely A, Park JY, Rosenfeld M, Wezeman J, Mangalindan R, Ratner D, Ladiges W. Intranasal GHK peptide enhances resilience to cognitive decline in aging mice. bioRxiv [Preprint]. 2023 Nov 17:2023.11.16.567423. doi:10.1101/2023.11.16.567423. PMCID: PMC10680828. Available from: https://pmc.ncbi.nlm.nih.gov/articles/PMC10680828/
  15. Wang Y, Zheng Z, Pathak JL, Cheng H, Huang S, Fu Z, Li P, Wu L, Zheng H. GHK-Cu/pionin-loaded in situ electrospun PVB/PVP smart dressing promotes wound healing via anti-oxidant, anti-inflammatory, antimicrobial, and tissue regenerative effects. Chem Eng J. 2024;492:152154. doi:10.1016/j.cej.2024.152154. Available from: https://doi.org/10.1016/j.cej.2024.152154
  16. National Center for Biotechnology Information. PubChem Compound Summary for CID 133697840, GHK-Cu. 2025. Available from: https://pubchem.ncbi.nlm.nih.gov/compound/GHK-Cu
  17. National Center for Biotechnology Information. PubChem Compound Summary for CID 168431292, AHK-Cu. 2025. Available from: https://pubchem.ncbi.nlm.nih.gov/compound/168431292