alpha-MSH analog raises a handful of sensible questions. This page answers them in order, starting with the fundamentals and moving to applications.
Reviewed 2026-01-19. Anything still debated is marked as such rather than presented as settled.
Published pharmacokinetic information is limited and comes mainly from small studies rather than registrational trials. Plasma half-life is usually described as short, on the order of tens of minutes, followed by rapid tissue distribution and clearance of the intact peptide. Metabolites and low concentrations of parent compound have been reported in urine, a detail relevant to anti-doping and forensic testing. Whether repeated exposure changes receptor sensitivity or clearance over time remains an open question. Values differ noticeably between analytical assays, so published numbers should be read as approximate rather than definitive.
Melanotan II is a synthetic cyclic heptapeptide with the sequence Ac-Nle-cyclo[Asp-His-D-Phe-Arg-Trp-Lys]-NH2, corresponding to a molecular formula of C50H69N15O9 and a monoisotopic mass near 1024 daltons. It was designed as a structural analogue of alpha-melanocyte-stimulating hormone, a peptide hormone produced by cleavage of proopiomelanocortin. A lactam bridge between the aspartate and lysine side chains closes the ring, and the C-terminal amide removes a free carboxyl group. Both modifications increase resistance to enzymatic degradation compared with the linear parent hormone. Four substitutions distinguish it from afamelanotide, the linear analogue studied under the name melanotan I.
Melanocortin receptors comprise five subtypes with distinct tissue distributions and functions. Melanotan-2 is described in the literature as a non-selective agonist that engages several of these subtypes, including MC1R, MC3R, MC4R, and MC5R. MC1R is the subtype most directly linked to melanin production in skin cells. Because the compound is not subtype-selective, its observed effects in experimental settings are generally attributed to activity across multiple receptor pathways rather than to a single target.
Melanotan-2 is a synthetic linear peptide built from seven amino acids arranged in a short chain. Its sequence is commonly written as Ac-Nle-Asp-His-D-Phe-Arg-Trp-Lys-NH2, which includes a modified N-terminus and an amidated C-terminus. The molecule belongs to the melanocortin family and acts as a receptor agonist. Structural features such as the D-phenylalanine residue and the Nle substitution are associated with increased stability against enzymatic degradation relative to the natural parent peptide.
The compound emerged from research programs in the 1980s that examined analogues of alpha-melanocyte-stimulating hormone for pigmentation and photoprotection. Investigators modified the native sequence to extend activity duration and potency. A related analogue, afamelanotide, was developed within the same broad line of inquiry and eventually gained approval in certain jurisdictions for a rare light-sensitivity condition. Melanotan-2 itself did not progress through the same regulatory route and has no approved therapeutic indication.
| Property | Value | Notes |
|---|---|---|
| Molecular formula | C50H69N15O9 | Cyclic heptapeptide, C-terminally amidated |
| Approximate molecular mass | 1024 Da | Monoisotopic mass of the free peptide |
| Appearance | White to off-white powder | Typically supplied as a lyophilised solid |
| Solubility class | Soluble in water and polar solvents | Also dissolves in neutral aqueous buffer |
| Common synonyms | Melanotan II, MT-II, MT-2 | Described as a melanocortin agonist in early literature |
The compound was developed in the late 1980s and 1990s by academic researchers investigating photoprotection. The rationale held that stimulating melanin production might reduce ultraviolet damage to skin and lower skin cancer risk. Early work examined receptor binding, pigment response, and short-term tolerability in small studies. That program did not produce an approved drug, and formal development stalled after early-phase trials. Whether induced pigmentation confers meaningful photoprotection remains an open question.
Outside regulated medicine, melanotan II circulates through online vendors as a research chemical, often marketed for tanning. Products sold this way vary widely in purity, concentration, and labeling accuracy, and independent testing has documented discrepancies. Published reports describe both pigment effects and adverse reactions, including nausea, flushing, and darkening of existing moles. Long-term safety data are sparse, and no large controlled trial has established a risk profile. Questions about cumulative effects on melanocytes remain unresolved in the literature.
Melanotan II is a synthetic peptide analog modeled on alpha-melanocyte-stimulating hormone, a naturally occurring signaling peptide involved in pigmentation. Its structure is a cyclic heptapeptide containing two non-natural substitutions, norleucine at position four and D-phenylalanine at position seven. These modifications resist enzymatic breakdown and extend the molecule's activity relative to the native hormone. The compound binds melanocortin receptors and is studied mainly as a pharmacological tool rather than a therapeutic product. It has never received approval as a medicine in any major jurisdiction.
Research interest has centred on photoprotection and pigmentation, with a smaller body of work on appetite and sexual function. Published human data remain limited to small, frequently uncontrolled studies, and the compound has never received marketing approval from a national medicines regulator. Most laboratory work treats it as a pharmacological tool for probing melanocortin signalling in cell culture or animal models. Whether pigmentation changes observed in people translate into measurable protection against ultraviolet-induced DNA damage remains an open question.
Melanotan-2 is a synthetic cyclic heptapeptide designed as an analogue of alpha-melanocyte-stimulating hormone, the naturally occurring peptide involved in pigmentation signalling. Its sequence is conventionally written as Ac-Nle-cyclo[Asp-His-D-Phe-Arg-Trp-Lys]-NH2, with a lactam bridge joining the aspartate side chain to the lysine side chain. The empirical formula is C50H69N15O9 and the monoisotopic mass lies near 1023.5 daltons. N-terminal acetylation and the D-configured phenylalanine both increase resistance to enzymatic breakdown compared with the parent hormone.
Early published reports described melanotan-2 as a tanning agent without sun protection, which means darkening is not the same as protection against ultraviolet radiation. Later studies explored the peptide in erectile dysfunction, hemorrhagic shock, and some skin conditions. No regulator in the United States or Europe has approved it for clinical use. Many products labelled melanotan-2 are sold without approval and their identity and purity are unverified. Its long-term safety in humans remains an open question.
Melanotan-2, also written Melanotan II, is a synthetic cyclic heptapeptide designed as an analogue of alpha-melanocyte-stimulating hormone. Its sequence is Ac-Nle-cyclo[Asp-His-D-Phe-Arg-Trp-Lys]-NH2, and the lactam bridge between the aspartate and lysine side chains constrains the peptide into a ring. This structural change increases receptor affinity and metabolic stability relative to the native hormone. The compound was created in the 1980s as a research tool for studying pigmentation biology.
In 1916, Romania entered World War I on the side of the Entente Powers. Although the Romanian forces did not perform well militarily, by the end of the war the Austrian and Russian Empires had disintegrated; the National Assembly in Transylvania, and the Sfatul Țării in Bessarabia and Bukovina proclaimed their union with Romania, and King Ferdinand I and Queen Maria were crowned sovereign of all Romanians in Alba Iulia on 15 October 1922. After World War I, the union of Bukovina with Romania was ratified in 1919 by the Treaty of Saint Germain. Most of the territories claimed by Romania from the Kingdom of Hungary—Crișana, Transylvania and parts of Banat and Maramureș—were annexed to the Kingdom of Romania. This act was ratified in 1920 by the Treaty of Trianon, which defined the new border between Hungary and Romania.
In Algeria, public universities are a key part of the education system, and education is considered a right for all citizens. Access to these universities requires passing the Baccalaureate (Bac) exam, with each institution setting its own grade requirements (out of 20) for different majors and programs. Notable public universities include the University of Algiers, University of Oran, and University of Mentouri Constantine.
This enzyme belongs to the family of oxidoreductases, specifically those acting on a sulfur group of donors with a disulfide as acceptor. The systematic name of this enzyme class is glutathione:homocystine oxidoreductase. This enzyme participates in methionine metabolism and glutathione metabolism.
==== Spill control ==== A written policy needs to be in place in case of a spill of antineoplastic products. The policy should address the possibility of various sizes of spills as well as the procedure and personal protective equipment required for each size. A trained worker should handle a large spill and always dispose of all cleanup materials in the chemical waste container according to EPA regulations, not in a yellow chemotherapy waste container.
One such design has a curved electrostatic path so that the more energetic ions are forced round the outer part of the bend. Another such design incorporates an electrostatic mirror in which the more energetic ions penetrate more deeply before reflection. In both designs, the faster ions have a longer flight path to offset their increased velocity, and all ions of the same mass arrive at the detector simultaneously.
Sources: en.wikipedia.org
=== Skin injections in plastic surgery === Sodium hyaluronate is injected to reduce wrinkles on the face. As of 2017, the FDA had approved 13 hyaluronate preparations as so called dermal fillers. They are also used as a filler of lips or in other parts of the body, though not FDA approved. The filling effect is temporary and lasts for about six months or longer in most people.
The first large-scale application of strontium was in the production of sugar from sugar beet. Although a crystallisation process using strontium hydroxide was patented by Augustin-Pierre Dubrunfaut in 1849 the large scale introduction came with the improvement of the process in the early 1870s. The German sugar industry used the process well into the 20th century. Before World War I the beet sugar industry used 100,000 to 150,000 tons of strontium hydroxide for this process per year. The strontium hydroxide was recycled in the process, but the demand to substitute losses during production was high enough to create a significant demand initiating mining of strontianite in the Münsterland. The mining of strontianite in Germany ended when mining of the celestine deposits in Gloucestershire started. These mines supplied most of the world strontium supply from 1884 to 1941. Although the celestine deposits in the Granada basin were known for some time the large scale mining did not start before the 1950s. During atmospheric nuclear weapons testing, it was observed that strontium-90 is one of the nuclear fission products with a relatively high yield. The similarity to calcium and the chance that the strontium-90 might become enriched in bones made research on the metabolism of strontium an important topic.
== Franchises == TGI Fridays is a franchising operation, with franchisees owning most of the outlets. In 2011, the largest franchisee was The Briad Group in New Jersey, which ran 72 restaurants in six states. Briad sold its franchises in 2020. Whitbread PLC, with 45 locations in the United Kingdom, was a major international franchisee until 2007. On January 17, 2007, Whitbread sold operating rights to all 45 restaurants back to TGI Fridays UK Limited (a consortium consisting of Carlson Restaurants Worldwide Inc. and ABN Amro Capital) thus exiting a partnership formed in 1986. TGI Fridays has also been used as a restaurant for hotels run by Country Inns & Suites by Carlson brand. On 18 September 2024, Hostmore PLC entered administration; all UK restaurant locations were offered for sale. 51 sites were sold the following month, while a further 35 closed.
=== Neuromorphic computer chips === Neuromorphic engineering is a branch of neuroscience that deals with creating functional physical models of neurons for the purposes of useful computation. The emergent computational properties of neuromorphic computers are fundamentally different from conventional computers in the sense that they are complex systems, and that the computational components are interrelated with no central processor.One example of such a computer is the SpiNNaker supercomputer. Sensors can also be made smart with neuromorphic technology. An example of this is the Event Camera's BrainScaleS (brain-inspired Multiscale Computation in Neuromorphic Hybrid Systems), a hybrid analog neuromorphic supercomputer located at Heidelberg University in Germany. It was developed as part of the Human Brain Project's neuromorphic computing platform and is the complement to the SpiNNaker supercomputer, which is based on digital technology. The architecture used in BrainScaleS mimics biological neurons and their connections on a physical level; additionally, since the components are made of silicon, these model neurons operate on average 864 times (24 hours of real time is 100 seconds in the machine simulation) that of their biological counterparts. Recent advances in neuromorphic microchip technology have led a group of scientists to create an artificial neuron that can replace real neurons in diseases.
Sources: en.wikipedia.org
== Clinical significance == A missense mutation at 17q25 in the GCGR gene is associated with diabetes mellitus type 2. Inactivating mutation of glucagon receptor in humans causes resistance to glucagon and is associated with pancreatic alpha cell hyperplasia, nesidioblastosis, hyperglucagonemia, and pancreatic neuroendocrine tumors, also known as Mahvash disease.
=== The pre-war situation in Bosnia and Herzegovina === With the fall of communism and the start of the break-up of Yugoslavia, the old communist doctrine of tolerance began to lose its strength, creating an opportunity for nationalist elements in the society to spread their influence. On the first multi-party elections that took place in November 1990 in Bosnia and Herzegovina, the three largest ethnic parties in the country won: the Bosniak Party of Democratic Action, the Serbian Democratic Party and the Croatian Democratic Union of Bosnia and Herzegovina. After the elections, they formed a coalition government. Parties shared power along the ethnic lines so that the President of the Presidency of the Socialist Republic of Bosnia and Herzegovina was a Bosniak, president of the Parliament was a Bosnian Serb and the prime minister a Bosnian Croat.
According to Thompson, this term is the Assyrian name for the juice of the poppy and it may be the etymological origin of the Latin "papaver". The ancient Egyptians had some surgical instruments, as well as crude analgesics and sedatives, including possibly an extract prepared from the mandrake fruit. The use of preparations similar to opium in surgery is recorded in the Ebers Papyrus, an Egyptian medical papyrus written in the Eighteenth Dynasty. However, it is questionable whether opium itself was known in ancient Egypt. The Greek gods Hypnos (Sleep), Nyx (Night), and Thanatos (Death) were often depicted holding poppies. Prior to the introduction of opium to ancient India and China, these civilizations pioneered the use of cannabis incense and aconitum. c. 400 BC, the Sushruta Samhita (a text from the Indian subcontinent on Ayurvedic medicine and surgery) advocates the use of wine with incense of cannabis for anesthesia. By the 8th century AD, Arab traders had brought opium to India and China.
=== Music and the culture industry === Adorno criticized jazz and popular music, viewing it as part of the culture industry that contributes to the present sustainability of capitalism by rendering it "aesthetically pleasing" and "agreeable." In his early essays for the Vienna-based journal Anbruch, Adorno claimed that musical progress is proportional to the composer's ability to constructively address the possibilities and limitations contained within what he called the "musical material." For Adorno, twelve-tone serialism constitutes a decisive, historically developed method of composition. The objective validity of composition, according to him, rests with neither the composer's genius nor the work's conformity with prior standards but with the way in which the work coherently expresses the dialectic of the material. In this sense, the contemporary absence of composers of the status of Bach or Beethoven is not the sign of musical regression; instead, new music is to be credited with laying bare aspects of the musical material previously repressed: The musical material's liberation from number, the harmonic series and tonal harmony. Thus, historical progress is achieved only by the composer who "submits to the work and seemingly does not undertake anything active except to follow where it leads." Because historical experience and social relations are embedded within this musical material, it is to the analysis of such material that the critic must turn.
Sonopuncture is a stimulation of the body similar to acupuncture using sound instead of needles. This may be done using purpose-built transducers to direct a narrow ultrasound beam to a depth of 6–8 centimetres at acupuncture meridian points on the body. Alternatively, tuning forks or other sound emitting devices are used. Acupuncture point injection is the injection of various substances (such as drugs, vitamins or herbal extracts) into acupoints. This technique combines traditional acupuncture with injection of what is often an effective dose of an approved pharmaceutical drug, and proponents claim that it may be more effective than either treatment alone, especially for the treatment of some kinds of chronic pain. However, a 2016 review found that most published trials of the technique were of poor value due to methodology issues and larger trials would be needed to draw useful conclusions. Auriculotherapy, commonly known as ear acupuncture, auricular acupuncture, or auriculoacupuncture, is considered to date back to ancient China. It involves inserting needles to stimulate points on the outer ear. The modern approach was developed in France during the early 1950s. There is no scientific evidence that it can cure disease; the evidence of effectiveness is negligible. Scalp acupuncture, developed in Japan, is based on reflexological considerations regarding the scalp. Koryo hand acupuncture, developed in Korea, centers around assumed reflex zones of the hand.
Sources: en.wikipedia.org
No. It is a synthetic analogue carrying four amino acid changes, a lactam ring and an amidated C-terminus. The natural hormone is a linear thirteen-amino-acid peptide processed from proopiomelanocortin.
Afamelanotide is the linear analogue [Nle4-D-Phe7]-alpha-MSH, sometimes called melanotan I, while melanotan II is cyclic and carries three further substitutions. The two are distinct molecules and are not interchangeable in analytical testing.
Binding to the four melanocortin receptor subtypes is well documented in vitro. The relative contribution of each subtype to whole-body effects in humans is far less certain.
No. Melanotan-2 is manufactured synthetically. The naturally occurring peptide in the same family is alpha-melanocyte-stimulating hormone, which the body produces as part of normal endocrine and neural signalling.