alpha-MSH analogue 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 2026-08-01. Where a claim depends on a specific study, the study is described rather than over-claimed.
Lyophilized peptide powder is generally stored frozen, protected from light and moisture. Tryptophan residues are susceptible to oxidation, and the lactam bridge can hydrolyze under strongly acidic or basic conditions. Solutions prepared for laboratory work degrade faster than dry powder, and repeated freeze-thaw cycles accelerate loss. Common practice is to aliquot solutions before freezing and to avoid alkaline buffers. Reported stability windows vary with concentration, buffer, and temperature, so exact shelf lives are method-specific rather than universal.
Regulatory status differs by country, and in many places supplying the compound for human consumption is unlawful. Vendors frequently label material as intended for research use only, a designation that shifts stated purpose but does not create a legal pathway for personal use. Certificates of analysis accompanying such products vary widely in detail and provenance. Third-party testing exists but is voluntary, and results are rarely linked to a specific lot in a publicly verifiable way.
Identity testing for a synthetic peptide relies on several complementary methods. Reversed-phase high-performance liquid chromatography separates the target from related impurities and reports purity as a percentage of total peak area. Mass spectrometry confirms molecular mass and can reveal deletions or truncations. Amino acid analysis and peptide mapping provide sequence-level confirmation, while counter-ion content and residual solvents are measured separately. A purity figure alone does not establish identity, so a complete dataset combines chromatographic and spectrometric evidence.
Melanotan-2 is a synthetic cyclic heptapeptide designed as an analogue of alpha-melanocyte-stimulating hormone, a naturally occurring peptide involved in pigmentation signalling. Its sequence incorporates modified residues that increase potency and extend biological activity relative to the native hormone. The compound binds receptors of the melanocortin family and is examined mainly in laboratory research. It does not occur naturally and exists only as a manufactured chemical entity produced by solid-phase synthesis.
The peptide was developed during the 1980s by researchers investigating melanocortin signalling and skin pigmentation pathways. Early work focused on analogues of alpha-melanocyte-stimulating hormone that would resist enzymatic breakdown more effectively than the parent molecule. Melanotan-2 emerged from that programme as a shortened, cyclised variant. Reports describing its synthesis and receptor activity later appeared in the scientific literature. Commercial availability grew through unregulated channels rather than through pharmaceutical approval.
| Property | Value | Notes |
|---|---|---|
| Molecular formula | C50H69N15O9 | Free base; salt forms differ |
| Molecular mass | About 1024.2 g/mol | Monoisotopic value for the free base |
| Appearance | White to off-white lyophilized powder | Visual inspection is not an identity test |
| Solubility | Soluble in water and polar organic solvents | Dissolution depends on salt form and pH |
| Typical storage | -20 °C, dry, protected from light | Powder is more stable than prepared solutions |
Solid peptide kept dry at minus twenty degrees Celsius, shielded from light and moisture, is generally considered stable for extended periods. Solutions are divided into single-use aliquots and held at minus twenty or minus eighty degrees Celsius, because repeated freeze-thaw cycles promote aggregation and loss of material to container surfaces. Hydrolysis of the backbone and oxidation of tryptophan are the principal degradation routes in aqueous solution, and both accelerate at ambient temperature. Hygroscopic uptake after a vial is opened can also shift the actual mass weighed, which affects any concentration calculated from it.
Routine characterisation relies on reversed-phase high-performance liquid chromatography with ultraviolet detection near 214 nanometres, using a C18 column and a water-acetonitrile gradient containing trifluoroacetic acid. Electrospray ionisation mass spectrometry confirms the expected molecular mass and can reveal truncated or oxidised by-products that co-elute poorly. Sequence and stereochemistry require additional work, such as peptide mapping or amino acid analysis, because a chromatographic purity figure alone does not distinguish a diastereomer from the target peptide. Independent testing of research-grade material frequently shows measured content below the stated label, so a certificate of analysis is best read together with the method that produced it.
Melanotan-2 is handled in the laboratory as a lyophilised powder that dissolves readily in water, dimethyl sulfoxide and dimethylformamide, with limited solubility in ethanol. Stock solutions prepared in an organic solvent often precipitate when diluted into aqueous buffer, so gradual dilution with mixing is standard practice. The peptide carries a tryptophan residue and a histidine residue, both sensitive to oxidation and to alkaline conditions. Working solutions are therefore kept near neutral to slightly acidic pH, protected from light, and consumed within the same working session whenever that is practical.
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.
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.
Regulatory treatment of this peptide varies by country. It holds no marketing authorization as a medicine in the United States, the European Union, or most other jurisdictions. Some countries classify products containing it as prescription-only or unlicensed medicines, which restricts lawful supply. Authorities have issued public notices warning that unregulated products may contain undeclared or incorrect ingredients. The molecule also appears on prohibited lists for competitive sport. These measures address supply oversight rather than any approved therapeutic role.
Published research on the compound remains limited. Much of the human data comes from small, early-stage studies rather than large controlled trials, and several questions about effects and variability between individuals remain open. Investigators have examined receptor activity, pigment pathways, and related physiological responses in laboratory and animal models. Findings from those models do not automatically translate to human outcomes. Reviews frequently note the scarcity of rigorous clinical evidence and call for better-characterized study material.
Because the substance circulates mainly through informal markets, verification is a recurring theme in technical discussion. Independent analyses have found that labeled content and actual content can diverge, and that purity varies between samples. Analytical laboratories use reversed-phase chromatography to separate components and mass spectrometry to confirm identity. Isotope-labeled internal standards improve quantification in complex matrices. Such methods describe what a sample contains but say nothing about its sterility, lawful status, or suitability for any use. Open questions remain about how consistently testing is applied across the supply chain.
Melanotan-2 is a synthetic cyclic heptapeptide designed as an analogue of alpha-melanocyte-stimulating hormone. Its sequence incorporates a lactam bridge that constrains the peptide into a ring, which increases resistance to enzymatic breakdown relative to the natural hormone. Researchers at the University of Arizona synthesised the compound in the late 1980s and early 1990s while studying pigmentation pathways. It has never received marketing approval from any national medicines regulator. In the scientific literature it is usually described as a laboratory research reagent rather than a therapeutic product.
The peptide acts as a non-selective agonist at melanocortin receptors, showing affinity for MC1R, MC3R, MC4R and MC5R. Activation of MC1R on melanocytes drives the conversion of tyrosine into melanin and shifts production toward the darker eumelanin form. MC4R signalling in the central nervous system is linked to appetite and energy balance, which helps explain why reduced food intake appeared in early human studies. Effects on MC4R and on vascular tone also account for the erectile responses recorded as unexpected findings in those same trials.
== Meetings == The APS organizes a four-day annual meeting called the Lorne Proteomics Symposium, traditional starting on the first Thursday of February, in Lorne, Victoria. In addition, the APS is active in organizing other symposia both in Australia and in New Zealand.
=== Condensate microenvironment === The condensate microenvironment refers to the distinct internal physical and chemical conditions within biomolecular condensates that influence molecular behavior and biochemical activity. These environments can differ markedly from the surrounding cellular milieu in terms of material property, pH, and chemical property. Rather than acting solely as passive concentration hubs, condensates modulate their internal milieu to promote selective partitioning, regulate reaction kinetics, and enable context-specific biological functions. Experimental studies have revealed several mechanisms by which condensate microenvironments operate. The material properties of condensates have been linked to condensate composition and functions. Nucleolar condensates have been shown to maintain internal pH gradients that influence RNA processing and protein composition. Other studies have demonstrated that different nuclear condensates exhibit distinct solvent characteristics, shaping the partitioning behavior of small molecules and biochemical cofactors. Further direct evidence comes from experiments using synthetic tools to manipulate condensate material properties. One study introduced a genetically encoded peptide, killswitch, that selectively arrests condensate dynamics without disrupting their scaffolds, enabling controlled perturbation of condensate material property in live cells. This intervention altered the protein composition of transcriptional condensates and impaired their biological activity.
Indeed, SIRT3 deacetylates and activates the mammalian mitochondrial acetyl-coA synthetase (AceCS2). Furthermore, SIRT3 and AceCS2 are found complexed with one another, suggesting a critical role for control of AceCS2 activity by SIRT3. Activation of the NMNAT2 enzyme, which catalyze an essential step in the nicotinamide adenine dinucleotide (NAD+) biosynthetic pathway by SIRT3 may be a means of inhibiting axon degeneration and dysfunction.
Sources: en.wikipedia.org
Exercising regularly, as exercise increases cellular sugar uptake, which decreases excessive insulin release. Avoiding eating meals or snacks composed entirely of carbohydrates; simultaneously ingest fats and proteins, which have slower rates of absorption; Consistently choosing longer lasting, complex carbohydrates to prevent rapid blood-sugar dips in the event that one does consume a disproportionately large amount of carbohydrates with a meal; Monitoring any effects medication may have on symptoms. Low-carbohydrate diet and/or frequent small meals is the first treatment of this condition. The first important point is to add small meals at the middle of the morning and of the afternoon, when glycemia would start to decrease. If adequate composition of the meal is found, the fall in blood glucose is thus prevented. Patients should avoid rapidly absorbed sugars and thus avoid popular soft drinks rich in glucose or sucrose. They should also be cautious with drinks associating sugar and alcohol, mainly in the fasting state. As it is a short-term ailment, a sugar crash that was not caused by injecting too much insulin does not usually require medical intervention in most people. The most important factors to consider when addressing this issue are the composition and timing of foods. Acute (short-term) low blood sugar symptoms are best treated by consuming small amounts of sweet foods, so as to regain balance in the body's carbohydrate metabolism. Suggestions include sugary foods that are quickly digested, such as:
=== Metabolism === The metabolism of progesterone is rapid and extensive, and it occurs mainly in the liver, though enzymes that metabolize progesterone are also expressed widely in the brain, skin, and various other extrahepatic tissues. Progesterone has an elimination half-life of only approximately five minutes in circulation. The metabolism of progesterone is complex, and it may form as many as 35 different unconjugated metabolites when it is ingested orally. Progesterone is highly susceptible to enzymatic reduction via reductases and hydroxysteroid dehydrogenases because of its double bond (between the C4 and C5 positions) and its two ketones (at the C3 and C20 positions). The major metabolic pathway of progesterone is reduction by 5α-reductase and 5β-reductase, into the dihydrogenated 5α-dihydroprogesterone and 5β-dihydroprogesterone, respectively. This is followed by the further reduction of these metabolites via 3α-hydroxysteroid dehydrogenase and 3β-hydroxysteroid dehydrogenase into the tetrahydrogenated allopregnanolone, pregnanolone, isopregnanolone, and epipregnanolone. Subsequently, 20α-hydroxysteroid dehydrogenase and 20β-hydroxysteroid dehydrogenase reduce these metabolites to form the corresponding hexahydrogenated pregnanediols (eight different isomers in total), which are then conjugated via glucuronidation and/or sulfation, released from the liver into circulation, and excreted by the kidneys into the urine.
=== Fungi === The condition is thought to be due to a local inflammatory response to overgrowth by Malassezia fungi species in sebum-producing skin areas including the scalp, face, chest, back, underarms, and groin. This is based on observations of high counts of Malassezia species in skin affected by seborrhoeic dermatitis and on the effectiveness of antifungals in treating the condition. Species of Malassezia implicated in Seborrhoeic dermatitis include M. furfur (formerly Pityrosporum ovale), M. globosa, M. restricta, M. sympodialis, and M. slooffiae. Malassezia appears to be a significant factor in seborrhoeic dermatitis, but it is thought that other factors are necessary for the presence of Malassezia to result in seborrhoeic dermatitis. For example, summer growth of Malassezia in the skin alone does not result in seborrhoeic dermatitis. Besides antifungals, the effectiveness of anti-inflammatory drugs, which reduce inflammation, and antiandrogens, which reduce sebum production, provide further insights into the pathophysiology of seborrhoeic dermatitis.
== History == In 1950, a small amount of CoQ10 was isolated from the lining of a horse's gut, a compound initially called substance SA, but later deemed to be quinone found in many animal tissues. In 1957, the same compound was isolated from mitochondrial membranes of beef heart, with research showing that it transported electrons within mitochondria. The compound was called Q-275 as a quinone. The Q-275/substance SA was later renamed ubiquinone as it was a ubiquitous quinone found in all animal tissues. In 1958, its full chemical structure was reported. Ubiquinone was later called either mitoquinone or coenzyme Q due to its participation to the mitochondrial electron transport chain. In 1966, a study reported that reduced CoQ6 was an effective antioxidant in cells.
Sources: en.wikipedia.org
==== Rookie of the Year Award and early career (1991–1993) ==== The Astros invited Bagwell to major league camp in spring training of 1991. Bagwell, expecting for the club to assign him to their Triple-A affiliate in Tucson, enthused them with his play. Because they, too, already had an established major leaguer at third base in Ken Caminiti, they approached Bagwell about shifting to first base, which he accepted. Having not previously played the position as a regular, Bagwell received a crash course, playing minor league games in the morning and Astros games in the afternoon until Opening Day. Observed The Sporting News: "Rookie Jeff Bagwell never played first base before this spring, but the position is his to lose. It's up to his bat." Thus, Bagwell made the major league club without an assignment to AAA, making the uncommon jump from AA to the major leagues, and made his major league debut on Opening Day. On May 6, he hit the ninth-ever upper-deck home run at Three Rivers Stadium off Bob Kipper in a seventh-inning pinch hit appearance, estimated at 456 feet (139 m). Bagwell hit .350 in September. He finished the year hitting .294 with 15 home runs and 82 RBI while leading the Astros in several offensive categories. He was named the 1991 National League (NL) Rookie of the Year, the first Astros player to win the award, Baseball America's Rookie of the Year, The Sporting News Rookie of the Year and postseason All-Star and on the Topps' Rookie All-Star Team. Bagwell's power hike piqued the curiosity of many baseball observers.
The first ENSO pattern to be recognised, called Eastern Pacific (EP) ENSO, to distinguish it from others, involves temperature anomalies in the eastern Pacific. In the 1990s and 2000s, variations of ENSO conditions were observed, in which the usual place of the temperature anomaly (Niño 1 and 2) is not affected, but an anomaly also arises in the central Pacific (Niño 3.4). The phenomenon is called Central Pacific (CP) ENSO, "dateline" ENSO (because the anomaly arises near the dateline), or ENSO "Modoki" (Modoki is Japanese for "similar, but different"). There are variations of ENSO additional to the EP and CP types, and some scientists argue that ENSO exists as a continuum, often with hybrid types. The effects of the CP ENSO are different from those of the EP ENSO. The El Niño Modoki is associated with more hurricanes more frequently making landfall in the Atlantic. La Niña Modoki leads to a rainfall increase over northwestern Australia and northern Murray–Darling basin, rather than over the eastern portion of the country as in a conventional EP La Niña. Also, La Niña Modoki increases the frequency of cyclonic storms over Bay of Bengal, but decreases the occurrence of severe storms in the Indian Ocean overall. The first recorded El Niño that originated in the central Pacific and moved toward the east was in 1986. Recent Central Pacific El Niños happened in 1986–87, 1991–92, 1994–95, 2002–03, 2004–05 and 2009–10. There were "Modoki" events in 1957–59, 1963–64, 1965–66, 1968–70, 1977–78 and 1979–80.
Anne S. Ulrich (born December 31, 1966) is a German chemist. She is the director of the Institute of Biological Interfaces (IBG-2) and Chair of Biochemistry at the Karlsruhe Institute of Technology. She studied chemistry at the University of Oxford - continued her doctoral work in the laboratory of Anthony Watts - held subsequent research positions as an EMBO-Fellow with Hartmut Oschkinat at the European Molecular Biology Laboratory in Heidelberg and as a Liebig-Fellow with Felix Wieland at the University of Heidelberg - became Associate Professor at the University of Jena - until she moved her group in 2002 to the Karlsruhe Institute of Technology. Her research focuses on the structural and functional analysis of biomembranes by solid state NMR. The main systems of interest are:
Sources: en.wikipedia.org
Dry powder is usually held frozen, shielded from light, and kept away from moisture. Desiccant packaging limits hydrolysis during storage. Solutions are typically aliquoted and frozen once, because repeated thawing shortens useful life.
Mass spectrometry establishes molecular mass, and reversed-phase chromatography reports purity. Peptide mapping or amino acid analysis supports sequence-level confirmation. No single technique covers all failure modes, so laboratories combine results.
Common entries include appearance, purity by chromatographic area, measured mass, and sometimes residual solvents or counter-ion content. Methods and instrument conditions are not always described. The document reflects the supplier's own testing unless an independent laboratory is named.
It is a synthetic cyclic heptapeptide and an analogue of alpha-melanocyte-stimulating hormone. The molecule is produced by chemical synthesis rather than extracted from a biological source.