alpha-MSH analog is one of those subjects where the details matter more than the headlines. This page pulls together the background, the mechanisms, and the practical points readers ask about most.
Last reviewed on 2026-04-03. Where a claim depends on a specific study, the study is described rather than over-claimed.
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.
Melanotan-2 appears on the World Anti-Doping Agency prohibited list within the peptide hormone class, and several national regulators treat it as an unapproved prescription substance. Some countries restrict importation or sale for personal use. Because the compound is widely traded as a research chemical, the practical legal picture differs between jurisdictions and shifts over time. Human safety data covering long periods are limited, and whether repeated pigmentation changes carry any lasting risk to melanocytes remains an open question.
Freeze-dried melanotan-2 is normally kept as a desiccated powder at minus twenty degrees Celsius or lower, shielded from light and moisture. Peptides of this size degrade through hydrolysis, oxidation and deamidation, and each pathway accelerates as temperature and water activity rise. Repeated freeze-thaw cycles promote aggregation and loss of material, so aliquoting a stock solution before freezing is standard laboratory practice. Once dissolved, the solution is markedly less stable than the powder. In laboratory work, solutions are generally refrigerated and used within days rather than kept for months.
Identity and purity are usually assessed by reversed-phase high-performance liquid chromatography, which separates the target peptide from truncated or oxidised impurities. Mass spectrometry, most often coupled to liquid chromatography, confirms molecular mass and detects substitutions that chromatography alone may miss. Amino acid analysis and peptide mapping supply additional structural evidence, while nuclear magnetic resonance is reserved for full structural confirmation. Laboratories that examine samples sold online report wide variation in actual content, with some vials containing little or none of the labelled material.
| 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 |
Melanotan II binds several melanocortin receptor subtypes rather than a single target. MC1R on melanocytes drives melanin synthesis, while MC3R and MC4R participate in energy balance, appetite, and sexual response pathways. This lack of selectivity explains why reported effects extend beyond skin darkening. Substitutions at positions four and seven, including norleucine and D-phenylalanine, increase potency and resistance to peptidases. Understanding which receptor mediates which effect remains an active area of investigation.
Published human data come mostly from small, short studies rather than large controlled trials. Reported outcomes include increased skin pigmentation and, in some reports, effects on appetite and libido, but sample sizes are small and follow-up is limited. Whether long-term use produces durable pigment changes or adverse effects is not established. Because products sold outside pharmacies are not standardized, the actual content of any given vial is often unknown. Independent testing of such material is uncommon.
Melanotan II is a synthetic cyclic heptapeptide analog derived from the core sequence of alpha-melanocyte-stimulating hormone. Researchers at the University of Arizona synthesized it during the 1980s while studying pigmentation and appetite signaling. The compound is not an approved medicine in any major jurisdiction and appears mainly in laboratory and research-chemical settings. Its structure incorporates a lactam bridge between side chains, which constrains the ring and slows enzymatic breakdown relative to the natural hormone.
Regulatory treatment varies by country. In the United States, melanotan-2 is not approved for any indication, and products marketed for human use fall outside the approved drug framework. Some other jurisdictions have placed it under prescription controls or listed it as a prohibited or restricted substance. Online listings frequently describe the material as a research chemical, a category that does not carry the same manufacturing and labelling requirements as approved medicines.
Solid peptide material is generally stable when kept cold and dry. Common practice is storage at -20 degrees Celsius or lower, with desiccant and protection from light. Repeated freeze-thaw cycles and exposure to moisture are associated with degradation, aggregation, or loss of material. Once dissolved, stability depends on solvent, concentration, and temperature, and solutions are usually treated as short-lived unless stability data support longer periods. Handling notes typically emphasise minimising time at ambient temperature.
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.
== Mechanism == The protein obeys Michaelis-Menton kinetics and has an associated KM of 278 ± 49 μM. The GYDQL and YFPQA motifs on the C-terminal binds cystinosin to the lysosome. Mutations in the GYDQL motif cause a repositioning of cystinosin to being partially on the plasma membrane and partially on the lysosome. Mutations in both GYDQL and YFPQA motifs cause cystinosin to position itself to the plasma membrane instead of lysosomes An increase in acidity in the lumen of the lysosome initiates the reaction of CySS and H+ being transported into the cytosol.
Interferon beta-1a administered subcutaneously or intravenously was investigated since March 2020 as a potential treatment in patients hospitalized with COVID-19 in a multinational Solidarity trial (initially in combination with lopinavir) but it did not reduce in-hospital mortality compared to local standard of care. SNG001, an inhalation formulation of interferon beta-1a, is being developed as a treatment for COVID-19 by Synairgen. A pilot trial in hospitalized patients showed higher odds of clinical improvement with SNG001 compared to placebo and in January 2021 a phase 3 trial in this population started.
==== In media ==== In the 1998 Chinese movie The Great Military March Forward: Engulf the Southwest, Liu was played by actor Yang Ciyu. In the 2009 Chinese historical drama The Founding of a Republic, Liu was played by filmmaker John Woo, but his role was cut from the final film.
DeMarco also observed this coordinated healing in humans with his gangrene patients. Despite being diabetic, the treated wound would heal correctly with minimal scar tissue. Even the toe’s print pattern would return. Hair growth and scar tissue were suppressed while select de novo protein synthesis appeared to accelerate. He deduced that this coordinated healing pattern was a result of procaine-DNA interaction since procaine has been documented to influence DNA synthesis in simpler life forms (DNA activation in sea urchin eggs) as well as humans (restores silenced gene expression).
In May 2015, the company announced the closure of its U.S. headquarters in Dublin, Ohio; in March 2015, it had 127 employees. In August 2016, Tim Hortons again changed presidents. In September 2016, Tim Hortons announced it would be expanding into the United Kingdom, with an unannounced number of locations to be built. Revenue in 2015 for Restaurant Brands International was US$4.0522 billion with a rise to $4.15 billion in 2016. Tim Hortons had 683 U.S. locations by the end of 2016, and total annual revenue of US$3.00 billion. In April 2018, Tim Hortons announced that they would be moving their head office along with its 400 employees to the Exchange Tower in downtown Toronto. In May 2018, the Reputation Institute reported that Tim Hortons had fallen from 13th to 67th in its study of Canada's most reputable companies, as "one of the largest moves down of all 250 companies it analyzed this year'" and that the brand was "still considered to have a 'strong reputation.'" In October 2018, Tim Hortons began to install self-serve kiosks at some locations in Ontario. In February 2019, Tim Hortons began to spread the installation of the self-serve kiosks across Canada.
Sources: en.wikipedia.org
== Use == The juice is drinkable, yet not palatable in its pure form due to its bitter taste. The bitterness diminishes as the hemp juice is mixed with fruit or vegetable juices. The hemp juice simultaneously heightens the fruity, savory and sweet taste of juices and foods in general. Therefore hemp juice is often used in drinks, certain food dishes, seasoning, food supplements, medical products as well as cosmetics. The press remnants can also be used as food supplements.
Electrons can enter the chain at three levels: at the level of a dehydrogenase, at the level of the quinone pool, or at the level of a mobile cytochrome electron carrier. These levels correspond to successively more positive redox potentials, or to successively decreased potential differences relative to the terminal electron acceptor. In other words, they correspond to successively smaller Gibbs free energy changes for the overall redox reaction. Individual bacteria use multiple electron transport chains, often simultaneously. Bacteria can use a number of different electron donors, a number of different dehydrogenases, a number of different oxidases and reductases, and a number of different electron acceptors. For example, E. coli (when growing aerobically using glucose and oxygen as an energy source) uses two different NADH dehydrogenases and two different quinol oxidases, for a total of four different electron transport chains operating simultaneously. A common feature of all electron transport chains is the presence of a proton pump to create an electrochemical gradient over a membrane. Bacterial electron transport chains may contain as many as three proton pumps, like mitochondria, or they may contain two or at least one.
Hong Kong has a humid subtropical climate (Köppen Cwa), characteristic of southern China, closely bordering on a tropical monsoon climate. Summers are long, hot, and humid, with occasional showers and thunderstorms and warm air from the southwest. The humid climate of Hong Kong intensifies summer heat. Typhoons occur most often then, sometimes resulting in floods or landslides. Also rarely occurring are waterspouts and tornadoes, which occurred at Hong Kong International Airport on 26 September 2020 and at Victoria Harbour on 28 September 2024. Winters are short, mild and usually sunny at the beginning, becoming cloudy towards February. Frequent cold fronts bring strong, cooling winds from the north and occasionally result in chilly weather. Autumn is the sunniest season, whilst spring is generally cloudy. Snowfall has been extremely rare in Hong Kong; the last reported instance was on Tai Mo Shan in 1975. Hong Kong averages 1,709 hours of sunshine per year. Historic temperature extremes at the Hong Kong Observatory are 36.9 °C (98.4 °F) on 9 August 2026 and 0.0 °C (32.0 °F) on 18 January 1893, record highest daily minimum temperature there was 30.2 °C (86.4 °F) on 12 August 2026 and the lowest daily maximum temperature there was 3.2 °C (37.8 °F) on 16 January 1893. The highest and lowest recorded temperatures in all of Hong Kong are 39.8 °C (104 °F) at Sheung Shui on 9 August 2026, and −6.0 °C (21.2 °F) at Tai Mo Shan on 24 January 2016.
== Organisational structure == The NNPC's business operations are managed through Strategic Business and Corporate Services Units (SBUs/CSUs) in diverse locations across Nigeria. The NNPC Group comprises the NNPC Board, the group managing director's office, Five directorates as listed below. Each of the directorate is headed by an executive vice president (EVP). Its divisions are headed by chiefs, while its subsidiary companies are headed by managing directors. NNPC has several subsidiaries, two partly owned subsidiaries and 16 associated companies. Directorates:
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.
The lyophilised solid is best kept cold, dry and dark, typically at minus twenty degrees Celsius. Moisture and repeated warming cycles are the main causes of degradation. Solutions prepared from the powder are less stable and are normally used quickly.