The short version of copper(II) complex fits in a sentence. The long version — which is the one that helps — is below.
Reviewed 2025-10-25. Anything still debated is marked as such rather than presented as settled.
GHK-Cu is a coordination complex formed between the tripeptide glycyl-L-histidyl-L-lysine and a copper(II) ion. The peptide backbone consists of glycine, histidine, and lysine joined in that order. Copper is held through the imidazole nitrogen of histidine and the alpha-amino group at the N-terminus, which together produce a square-planar arrangement around the metal center. The solid appears blue to violet, a color that originates from d-d electronic transitions within the copper coordination sphere. The complex is indexed under CAS number 89030-95-5.
The sequence now called GHK was first reported in the early 1970s after isolation from human plasma, where it was noted to influence liver cell behavior in laboratory preparations. Later work described a copper-binding form and its activity in fibroblast and wound-model experiments. Review articles frequently group the substance with other copper peptides. Concentrations in blood appear to fall with age in several small surveys, although the reason for this trend is not settled. Whether such a decline carries functional consequences remains an open question.
Published work on GHK-Cu concentrates largely on cell culture systems rather than whole organisms. Frequently used endpoints include collagen synthesis, expression of matrix metalloproteinases, and migration of fibroblasts. Some reports describe antioxidant behavior, while others stress delivery of copper into cells. These mechanisms are proposed rather than demonstrated, and the relative weight of each pathway is unclear. Human trials are few and generally small, so laboratory findings should not be read as confirmed clinical results.
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.
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.
| Property | Value | Notes |
|---|---|---|
| Chemical class | Copper(II) peptide complex | Peptide chain coordinated to a single metal ion |
| CAS number | 89030-95-5 | Indexed for the peptide-copper complex |
| Molecular formula | C14H22CuN6O4 | Approximate formula for a one-to-one complex |
| Appearance | Blue to violet solid | Color from copper d-d transitions |
| Solubility class | Freely soluble in water | Also dispersible in some polar solvents |
Several names circulate for the same material, which complicates literature searches. Cosmetic ingredient lists often use copper tripeptide-1, while older biochemistry papers use glycyl-L-histidyl-lysine or its abbreviation GHK. The copper complex is sometimes written as GHK-Cu(II) to make the oxidation state explicit. Terminology is not fully standardized, so matching a compound across sources requires attention to the exact sequence, the counterion, and the stated copper content. Reviews that compare studies must account for these naming differences before drawing conclusions.
GHK-Cu is the copper(II) complex of the tripeptide glycyl-L-histidyl-L-lysine, a short sequence of three amino acids. The peptide was first isolated from human plasma in 1973 during research on factors that influence tissue repair in liver. Its ability to bind copper ions became a central point of interest because the metal changes the peptide's chemistry and its behaviour in laboratory systems. Today the compound appears in cosmetic formulations, cell-culture studies, and biochemistry literature under several names.
The peptide sequence places a histidine in the middle, and this residue dominates metal binding. Copper(II) coordinates through the imidazole nitrogen of histidine and the terminal amino group, forming a stable chelate ring system. Loss of the copper ion leaves the free tripeptide, which has different solubility and reactivity. This structural detail matters because assays that measure only the peptide backbone can miss whether copper is still bound to it.
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.
Material described in research and cosmetic supply chains is typically a synthetic peptide supplied as a lyophilized powder. Purity is commonly reported through chromatographic separation, often at 95 percent or higher, while copper content is confirmed by separate elemental analysis. Batch variation in color and solubility can reflect residual counter-ions, moisture, or partial oxidation of the peptide. Because the complex is not a single regulatory entity, specifications differ between suppliers and are not standardized internationally.
GHK-Cu is a coordination complex formed between the tripeptide glycyl-L-histidyl-L-lysine and a copper(II) ion. The peptide binds copper through its histidine imidazole nitrogen, its terminal amino group, and a deprotonated amide nitrogen, creating a stable chelate ring. The resulting complex carries a distinctive blue to blue-violet color, which arises from copper d-d electronic transitions. In the solid state it is usually handled as a powder, while in solution the complex can dissociate and re-form depending on pH and competing ligands. The name copper tripeptide-1 is widely used in ingredient listings.
In March 2002, as part of Task Force K-Bar, ODAs from 3rd SFG took part in Operation Anaconda, at around midnight on March 2, Task Force Hammer (consisting of Special Forces A-teams Texas 14/ODA 594 and 450 Afghan Militia Fighters led by Commander Zia Lodin) left their base at Gardez to take part in the operation. They were to enter the Shahikot valley from the north, then they would assault through the villages of Serkhankheyl and Marzak, where intelligence indicated that the enemy was concentrated, and channel fleeing enemy into the Task Force Rakkasan blocking positions Several soldiers were injured when their truck overturned due to the poor condition of the road, they decided to use their headlights, even though they would lose the element of surprise. An AC-130 Gunship, callsign Grim 31, that was providing fire support and reconnaissance for the operation, spotted the convoy; and due to a problem with the aircraft's inertial navigation system the aircraft failed to identify the Column as friendly unit. Grim 31 engaged the convoy killing CWO Stanley Harriman and wounding two other Green Berets and Afghan militia.
With their large fore-flippers, eared seals are usually able to prevent the first bite from being secure, but are still weakened and vulnerable to being recaptured. Prey is released after it dies of blood loss, and the shark feeds on the carcass after it floats to the surface. In 1984, Timothy Tricas and John McCosker suggested that white sharks bite seals, release them, and then wait for them to bleed to death before eating based on observations at Dangerous Reef, South Australia. Others have found no evidence for this hypothesis, but the strategy is possibly employed on bull elephant seals. Off South Africa, ambushes on Cape fur seals usually involve the shark leaping or breaching out of the water. To breach, a shark starts at around 20 m (66 ft) below the surface and ascends quickly towards its target while tilting its body vertically. Sharks may breach partially or entirely out of the water at different angles, clearing up to around 3 m (10 ft) when airborne. Missed seals may be chased after; such pursuits involve the prey using its speed and agility to escape as the shark employs various maneuvers to catch them. The longer the chase, the less likely the shark is to succeed. Sharks commonly consume fur seals quickly after they are killed. White sharks in Cape Cod hunt seals in shallow water, relying on the murkiness of the water for concealment and striking them from the sides.
Rejuva is a gene therapy which is under development for the treatment of obesity and diabetes. It is an adeno-associated virus (AAV)-based gene therapy which involves an engineered variant of human insulin promotor and which aims to permanently increase nutrient-responsive secretion glucagon-like peptide-1 (GLP-1) by pancreatic β-cells. The therapy is administered via a 25-gauge needle delivery system guided by endoscopic ultrasound in a one-time outpatient treatment. It is intended as a permanent alternative to GLP-1 agonists like semaglutide. Rejuva is under development by Fractyl Health and is in the preclinical research stage of development.
The imprinted image turned out to be wash-resistant, impervious to temperatures of 250 °C (482 °F) and was undamaged by exposure to a range of harsh chemicals, including bisulphite, which, without the gelatine, would normally have degraded ferric oxide to the compound ferrous oxide. Instead of painting, it has been suggested that the bas-relief could also be heated and used to scorch an image onto the cloth. However researcher Thibault Heimburger performed some experiments with the scorching of linen, and found that a scorch mark is only produced by direct contact with the hot object—thus producing an all-or-nothing discoloration with no graduation of color as is found in the shroud.
Sources: en.wikipedia.org
=== Medication === Several medications may be used to block the actions of allergic mediators, prevent cell activation, and degranulation processes. These include antihistamines, glucocorticoids, epinephrine (adrenaline), mast cell stabilizers, and antileukotriene agents are common treatments of allergic diseases. Anticholinergics, decongestants, and other compounds thought to impair eosinophil chemotaxis are also commonly used. Although rare, the severity of anaphylaxis often requires epinephrine injection, and where medical care is unavailable, a device known as an epinephrine autoinjector may be used.
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== Structure == Erythroferrone in humans is transcribed as a precursor of 354 amino acids, with a signal peptide of 28 amino acids. The mouse gene encodes a 340 amino acid protein which is 71% identical. Homology is greater at the C-terminal where there is a TNF-alpha-like domain. As a member of the C1q/TNF-Related Protein (CTRP) family, erythroferrone has a 4-domain structure with a unique N-terminus. The two larger domains are connected by a short, proline-rich, collagenous linker that is thought to promote protein multimerization. Erythroferrone is predicted to contain two PCSK3/furin recognition sites. The protein hormone weighs approximately 35-40 kDa.
== Name == The Socialist Republic of Bosnia and Herzegovina was formed during a meeting of the State Anti-fascist Council for the National Liberation of Bosnia and Herzegovina (ZAVNOBiH) in Mrkonjić Grad on 25 November 1943. In April 1945, its name was formalized as the Federated State of Bosnia and Herzegovina (Serbo-Croatian: Federalna Država Bosna i Hercegovina / Федерална Држава Босна и Херцеговина), a constituent unit of the Democratic Federal Yugoslavia. With DF Yugoslavia changing its name to the Federal People's Republic of Yugoslavia on 29 November 1945 as well as the promulgation of the 1946 Yugoslav Constitution two months later in January, its constituent units also changed their respective names. FS Bosnia and Herzegovina thus became known as the People's Republic of Bosnia and Herzegovina (Narodna Republika Bosna i Hercegovina / Народна Република Босна и Херцеговина). This constitutional system lasted until the 1963 Yugoslav Constitution. On 7 April 1963, Yugoslavia was reconstituted as the Socialist Federal Republic of Yugoslavia, and PR Bosnia and Herzegovina changed its name to the Socialist Republic of Bosnia and Herzegovina (Socijalistička Republika Bosna i Hercegovina / Социјалистичка Република Босна и Херцеговина). After independence on 1 March 1992, the country was renamed to the Republic of Bosnia and Herzegovina. Following the Dayton Agreement that was in force, it became simply a federated state known as Bosnia and Herzegovina in 1997.
Examples include alpha-Amanitin containing mushrooms, kava, and aflatoxin producing molds. Pyrrolizidine alkaloids, which occur in some plants, can be toxic. Green tea extract is a growing cause of liver failure due to its inclusion in more products.
Sources: en.wikipedia.org
It is the copper complex of the tripeptide glycyl-L-histidyl-lysine. The metal ion is held by the histidine imidazole group and the peptide N-terminus. Most research on it concerns skin and wound models.
The tripeptide was first isolated from human plasma and has also been reported in saliva and urine. Plasma levels appear to decline with age in some small studies. Those observations rest on limited sample sizes.
It is not authorized as a systemic medicine in most countries. Cosmetic preparations list it as an ingredient rather than an active pharmaceutical substance. Legal status therefore differs by jurisdiction.
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.