Everything below concerns GHK-Cu. We keep the language plain, cite what the science says, and separate well-supported claims from open questions.
Updated 2025-11-24. Numbers and descriptions here follow the published literature rather than marketing material.
Copper binds to the peptide through the histidine imidazole nitrogen and the terminal amino group, forming a stable square-planar complex. Binding constants reported for copper(II) with GHK are high, so the peptide competes effectively for copper in solution. The complex absorbs visible light, which gives solutions a blue to violet colour. Whether the metal-free peptide has a distinct biological function of its own is still an open question; some work treats it mainly as a copper delivery vehicle, while other work reports peptide-specific effects.
The compound was first isolated from human plasma in the 1970s by Loren Pickart, who later described copper-binding activity in liver and other tissues. Early reports focused on its presence in blood and its ability to carry copper between proteins. Commercial and cosmetic use of the term 'copper peptide' has since broadened, and labels rarely distinguish GHK-Cu from other copper-binding fragments. This naming overlap makes literature searching harder, because cosmetic ingredient lists, supplier catalogues and laboratory papers use different vocabularies for the same molecule.
Commercial products list GHK-Cu as copper tripeptide-1, a cosmetic ingredient. Formulators value its blue color and water solubility, which allow incorporation into serums, creams, and masks. Regulatory treatment varies: in the United States it appears in cosmetics, while some jurisdictions classify certain claims as drug-like. The compound is not an approved drug for any indication. Studies continue to examine its effects on skin, hair, and wound repair, but dosage, delivery, and long-term safety questions remain open.
GHK-Cu is a coordination complex formed between the tripeptide glycyl-L-histidyl-L-lysine and copper(II). The peptide sequence consists of glycine, histidine, and lysine, and its imidazole and amino groups provide binding sites for the metal ion. In the complex, copper is held through nitrogen donors from the histidine side chain, the N-terminal amine, and deprotonated amide nitrogens. The resulting compound is intensely blue and water-soluble. It occurs naturally in human plasma, saliva, and urine at low concentrations.
The peptide was first isolated from human albumin in 1973 by Loren Pickart, who later described its copper-binding behavior. Early work linked the complex to wound healing and tissue remodeling. Plasma levels of GHK decline with age, a pattern that stimulated interest in topical and supplemental applications. Researchers have reported that the tripeptide influences collagen synthesis, antioxidant defense, and inflammatory signaling in cell and animal models. Human clinical evidence remains limited and often relies on small studies.
| Property | Value | Notes |
|---|---|---|
| Sequence | Gly-His-Lys | Three amino acids; histidine supplies the main copper-binding nitrogen |
| Bound metal | Copper(II) | Coordination is described as square-planar around the metal centre |
| Appearance | Blue to violet solid | Colour originates from copper d-d electronic transitions |
| Solubility class | Freely soluble in water | Aqueous solutions are often slightly acidic |
| Common synonyms | Copper tripeptide, Cu-GHK | Ingredient lists may say only 'copper peptide' without giving the sequence |
Research interest in GHK-Cu centers on its ability to deliver copper and to influence cellular processes in laboratory models. In cell culture and animal studies, the complex has been linked to collagen synthesis, antioxidant enzyme activity, and expression of genes associated with tissue remodeling. These effects are not equivalent to proven clinical outcomes. The mechanisms proposed include copper transfer to cuproenzymes, modulation of growth factor signaling, and interactions with extracellular matrix components. How much of the observed activity depends on intact GHK-Cu versus free copper or free peptide is not fully resolved.
The compound entered scientific literature in the 1970s, when plasma factors with copper-binding activity were isolated and characterized. Later work expanded into wound healing, skin biology, and cosmetic formulation, where copper tripeptide-1 became a recognized ingredient name. Most published studies remain preclinical or small-scale, and findings are often reported in specialized dermatology or peptide journals. Regulatory treatment varies: some jurisdictions allow it as a cosmetic ingredient, while research-grade material is sold for laboratory use. Questions about optimal delivery, target tissues, and long-term effects continue to be investigated rather than settled.
GHK-Cu is a coordination complex formed between the tripeptide glycyl-L-histidyl-lysine and a copper(II) ion. The peptide sequence is conventionally written as Gly-His-Lys, abbreviated GHK. Copper binds through the imidazole nitrogen of histidine, the alpha-amino group, and a deprotonated amide nitrogen, producing a square-planar geometry. The complex carries a net positive charge near physiological pH and is intensely blue in aqueous solution. The metal-free peptide is often written simply as GHK, while the copper-bound form is written GHK-Cu.
The compound was first isolated from human plasma by the biochemist Loren Pickart in 1973. Early work identified it as a factor that altered the behavior of cultured liver cells, and later studies linked it to connective tissue and wound-related processes. Reported plasma concentrations fall markedly between roughly age twenty and age sixty, a pattern that generated interest in copper peptide biology. Whether that decline has functional consequences remains an open question, because differences observed across age groups do not by themselves establish causation. Research interest later expanded into cosmetic and tissue-culture settings.
=== Environmental disturbance === American kestrels' response to environmental stress is measured as blood concentration of corticosterone (CORT), a hormone produced by the hypothalamic-pituitary-adrenal (HPA) axis that releases stored energy for essential body functions. Extended periods of elevated blood CORT levels may direct metabolic energy away from growth and reproduction. Thus, high levels of traffic disturbance and human development surrounding American kestrel nests are found to increase stress hormones leading to reproductive failure. Among successful nests, however, nestlings do not typically experience a higher stress response to environmental human disturbance, suggesting that they can tolerate a considerable degree of human activity near the nest.
=== Acquisition by Take-Two Interactive (2024–present) === Take-Two Interactive announced its plans to acquire Gearbox Entertainment and its intellectual properties from Embracer Group for $460 million on March 28, 2024, to be added under the 2K label. The acquisition also includes Gearbox Software with its satellite studios and Gearbox Publishing. Embracer will retain Gearbox San Francisco, Gearbox Shanghai, Lost Boys Interactive, Captured Dimensions, and Cryptic Studios, along with publishing rights to Remnant, Hyper Light Breaker, and other unannounced titles. Less than a day after the announcement, it was reported that an unknown number of employees were laid off from Gearbox. On June 12, 2024, Take-Two Interactive closed the Gearbox Software transaction.
== Intracrines in biology and cancer == Intracrines involvement in cancer is primarily through their regulation of growth factors, angiogenesis, and cellular signaling networks that contribute to tumor growth and therapy resistance.
By the end of August 1944 the German forces in Italy had formed the Gothic Line along the Apennine Mountains, and the 6th Division had come under the command of the US Fifth Army. The difficulty of using tanks in the mountains led to the Rhodesians of Prince Alfred's Guard temporarily adopting an infantry role, using dismounted tank machine-guns to support the Natal Carabineers during the fighting for Pistoia during early September. The Southern Rhodesian Anti-Tank Battery meanwhile converted partially from guns to 4.2-inch mortars. The South Africans and Rhodesians met with fierce resistance from the 16th SS Panzer Grenadier Division, but helped push the Germans northwards towards the Reno river. Hoping to repel Allied advances towards Bologna, the Germans took up positions on Monte Stanco overlooking the main roads towards the city. Two Allied assaults on the mountain—one by an Indian battalion, the other by the Royal Natal Carabineers—were repulsed. A third, larger attack at dawn on 13 October provided the Rhodesian Company of the Cape Town Highlanders with some of the fiercest combat they encountered in Italy. Advancing up the slope on the Allied right flank while being fired on from two directions, they suffered heavy casualties but achieved their objective and held it. Both Rhodesian artillery batteries provided support during the assault. When the line stabilised in November 1944, the portion occupied by the 6th Armoured Division extended for 16 kilometres (9.9 mi) along the heights over the Reno River.
Body fat cells have regional responses to the overfeeding that was studied in adult subjects. In the upper body, an increase of adipocyte size correlated with upper-body fat gain; however, the number of fat cells was not significantly changed. In contrast to the upper body fat cell response, the number of lower-body adipocytes did significantly increase during the course of experiment. Notably, there was no change in the size of the lower-body adipocytes. Approximately 10% of fat cells are renewed annually at all adult ages and levels of body mass index without a significant increase in the overall number of adipocytes in adulthood.
Sources: en.wikipedia.org
In September 2020, the European Medicines Agency (EMA) endorsed the use of dexamethasone in adults and adolescents, from twelve years of age and weighing at least 40 kilograms (88 lb), who require supplemental oxygen therapy. Dexamethasone can be taken by mouth or given as an injection or infusion (drip) into a vein. In November 2020, the Public Health Agency of Canada's Clinical Pharmacology Task Group recommended dexamethasone for hospitalized patients requiring mechanical ventilation. Although dexamethasone, and other glucocorticoids, reduce mortality in COVID-19 they have also been associated with an increased risk of secondary infections, secondary infections being a significant issue in critically ill COVID-19 patients. The mechanism of action of dexamethasone involves suppression of late-stage interferon type I programs in severe COVID-19 patients.
In cancer, there are substantial metabolic derangements that occur to ensure the proliferation of tumor cells, and consequently metabolites can accumulate which serve to facilitate tumorigenesis, dubbed oncometabolites. Among the best characterized oncometabolites is 2-hydroxyglutarate which is produced through a heterozygous gain-of-function mutation (specifically a neomorphic one) in isocitrate dehydrogenase (IDH) (which under normal circumstances catalyzes the oxidation of isocitrate to oxalosuccinate, which then spontaneously decarboxylates to alpha-ketoglutarate, as discussed above; in this case an additional reduction step occurs after the formation of alpha-ketoglutarate via NADPH to yield 2-hydroxyglutarate), and hence IDH is considered an oncogene. Under physiological conditions, 2-hydroxyglutarate is a minor product of several metabolic pathways as an error but readily converted to alpha-ketoglutarate via hydroxyglutarate dehydrogenase enzymes (L2HGDH and D2HGDH) but does not have a known physiologic role in mammalian cells; of note, in cancer, 2-hydroxyglutarate is likely a terminal metabolite as isotope labelling experiments of colorectal cancer cell lines show that its conversion back to alpha-ketoglutarate is too low to measure. In cancer, 2-hydroxyglutarate serves as a competitive inhibitor for a number of enzymes that facilitate reactions via alpha-ketoglutarate in alpha-ketoglutarate-dependent dioxygenases. This mutation results in several important changes to the metabolism of the cell.
==== Political resurgence ==== Heseltine, who had been seen as an arriviste in his younger days, was now something of a grandee and elder statesman. In 1994 he re-emerged as a serious political player, beginning with his testimony for the Scott Report during the Arms-to-Iraq Inquiry (whose report eventually appeared in 1996). It was revealed that he had refused to sign the Public Interest Immunity Certificates (attempting to withhold evidence from the trial in 1992, on grounds of national security) as demanded by the attorney-general Sir Nicholas Lyell, who advised him that ministers were obliged to sign such a certificate. In fact after half a dozen meetings over the course of a week, and Heseltine insisting on reading Bingham LJ's judgement in the Makanjuola case, Heseltine had agreed to sign a slightly different version of the PII which made clear his reservations. However, this was not picked up on at the trial, nor were Heseltine's concerns – contrary to assurances given to him by Lyell – that some of the documents might be useful to the defence passed on to the trial judge. Nonetheless, his evidence in February 1994 was seen as an attack on Lyell and on the ministers (Kenneth Clarke, his potential rival for the leadership, Rifkind and Tristan Garel-Jones) who had signed the certificates without demur.
Hemoglobin-based oxygen carriers (HBOCs) Palmer's lab identifies new ways to build HBOCs. Their design strategy focus on increasing the molecular diameter of HBOCs so they're unable to traverse across blood vessel walls into the tissue space and limit negative side-effects. Supporting Publications:
Sources: en.wikipedia.org
=== 1998 === 1 January The King of Chaos, an Equinox Special which was a fictional documentary or docudrama, set 15 years in the future with Danny Webb and Christine Kavanagh, followed by the documentary Storm Over 4, which featured Channel 4's most controversial programmes, including January 1995's Beyond Love; the documentary was one of three nominees for the Originality award in the 1999 British Academy Television Awards; the mock-documentary was fictionally presented by Bella Enahoro, daughter of Nigerian Anthony Enahoro; a body is found in the Thames, missing for two days, filmed near the South Quay Footbridge, built in 1997, a few months before the production was filmed in late 1997; Everett Barnes (Burt Caesar), chief of security of Keller Corp; Robert Sinclair, chief of Keller Corp; Keller gives a speech on 18 December 2011 at the Turing Seminar; reporter Helen Parker (Christine Kavanagh); Superintendent Andrea Walker (Janet Amsden); Richard Steiner, chief of Eagle Television, obviously resemblant of Rupert Murdoch; Keller had Bulgarian heritage; the non-fictional Prof Peter Cochrane, Head of Research at BT, but he talked about a fictional story; Victor Bunin (Olegar Fedoro); Jean Tate (Margaret Enefer, now a TV producer), fictional Channel 4 reporter; non-fictional American Rob Glaser, chief of RealNetworks; David Britten (Ben Aris), fictional Director-General of the BBC, outside the Queen Elizabeth II Centre; in 2002, 40% of subscription TV channels would close; fictional MP Jean Fransley (Su Elliott).
Other uses include determining high-precision values for plutonium and uranium isotopes in a rapid fashion, investigating the atomic properties of technetium at the ultra trace level, and capturing the concurrent excitation of stable daughter atoms with the decay of their parent atoms as is the case for alpha particles, beta rays, and positrons. RIS is now in very common use in research facilities where the quick and quantitative determination of the elemental composition of materials is important. Pulsed laser light sources provide higher photon fluxes than continuous-wave lasers do, however the use of pulsed lasers currently limit vast applications of RIMS in two ways. One, photo ions are created only during short laser pulses, thus significantly reducing the duty cycle of pulsed resonance ionization mass spectrometers relative to their continuous-beam counterparts. Two, incessant drifts in laser pointing and pulse timing alongside jitters between pulses severely hamper chances of reproducibility. These issues affect the extent to which resonance ionization can be used to solve some of the challenges confronted by practical analysts today; even so, applications of RIMS are replete in various traditional and emerging disciplines such as cosmochemistry, medical research, environmental chemistry, geophysical sciences, nuclear physics, genome sequencing, and semiconductors.
=== Modern era till 1900 === Wholesaling was central to economic development, especially in periods when manufacturing and retail were still small-scale. Before 1850s, wholesale merchants were multipurpose connectors who often provided financing, warehousing, information, freight coordination, and risk-taking, and who helped establish broader market systems. As transport and communication improved, wholesaling expanded and professionalized. From the mid-1850s, national markets began to take shape "due in part to the telegraph, the railroad and maritime transportation," increasing the separation between producers and buyers and creating larger "market gaps." As mass production emerged toward the end of the 19th century and producers clustered near inputs and transport, market gaps widened further, and a broader class of middlemen grew to close those gaps.
Sources: en.wikipedia.org
The letters GHK are the one-letter codes for glycine, histidine and lysine, the three amino acids in the peptide. The suffix Cu indicates that the peptide is bound to a copper ion, normally copper(II).
The free tripeptide and its copper complex have been measured in human plasma, saliva, urine and some tissue extracts. Reported concentrations vary widely between studies, and the role of the complex in normal physiology remains partly unresolved.
The plain peptide lacks the metal, so its charge, colour and binding behaviour differ. The copper complex is blue and carries a bound copper ion, while the metal-free form is colourless and has different solution chemistry.
GHK is the free tripeptide, while GHK-Cu includes a bound copper(II) ion. The copper complex is the form most often studied for skin and wound-related activity. The two names are sometimes used interchangeably in product labeling, but they refer to distinct chemical species.