This is a working overview of melanotan-2, written for readers who want more than a one-paragraph summary but less than a textbook.
This page was last updated on 2026-01-21 and is reviewed periodically as new material appears.
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.
Receptor studies place melanotan-2 among non-selective melanocortin agonists, binding MC1R, MC3R, MC4R and MC5R rather than a single subtype. Activation of MC1R on cutaneous melanocytes raises tyrosinase activity and shifts pigment synthesis toward eumelanin, which is darker and more photostable than pheomelanin. Central receptors, particularly MC4R, are associated with appetite suppression and with reported effects on sexual function. Because subtype selectivity is low, the same molecule engages pigment, metabolic and vascular pathways at once, and this breadth is a common explanation offered for the range of adverse events described in user reports.
No regulatory authority has approved melanotan-2 for human use, and several countries classify it as a prescription-only or controlled substance, which restricts lawful supply. Material sold online is generally labelled as a research chemical and is not required to meet pharmaceutical standards of identity or purity. Published human data consist mainly of small uncontrolled studies, case reports and adverse-event notifications, so the evidence base is descriptive rather than confirmatory. Whether repeated melanocyte stimulation alters long-term naevus behaviour remains an open question that no completed trial has resolved.
| Property | Value | Notes |
|---|---|---|
| Molecular formula | C50H69N15O9 | Free base; salt forms differ |
| Molecular weight | Approximately 1024 g/mol | Calculated for the free base |
| Appearance | White to off-white powder | Typically supplied as a lyophilised solid |
| Solubility | Soluble in water and polar solvents | Poorly soluble in non-polar solvents |
| Typical storage | -20 degrees Celsius, dry, protected from light | Refers to the solid form |
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.
Pharmacologically, melanotan-2 behaves as a non-selective agonist across the melanocortin receptor family. Binding at MC1R on dermal melanocytes promotes eumelanin synthesis, which underlies the tanning response described in early human work. Activity at the centrally expressed MC4R receptor is associated with reported effects on appetite and erectile function. Because the peptide does not discriminate strongly among receptor subtypes, attributing any single observed effect to one receptor pathway is generally not possible without selective antagonists or receptor knockout models.
=== P187s === One widespread single-nucleotide polymorphism of the NQO1 gene (NQO1*2), found homozygous in 4% to 20% of different populations, has found to be connected with different forms of cancer and a lowered efficiency of some chemotherapeutics like mitomycin C. This single nucleotide polymorphism leads to a proline serine exchange on position 187. NAD(P)H dehydrogenase [quinone] 1 P187S has been shown to have a lowered activity and stability. Crystallographic and nuclear magnetic resonance data show that the reason for this different behaviour is found in a flexible C-terminus of the protein leading to a destabilization of the whole protein. Recent pharmacological research suggests feasibility of genotype-directed redox chemotherapeutic intervention targeting NQO1*2 breast cancer. A comprehensive meta-analysis showed an association between overall cancer risk and P187S.
Combination of small size, ease of engineering, high affinity and specificity makes Affibody molecules suitable alternative as monoclonal antibodies for both molecular imaging and therapeutical applications, especially for the receptor-overexpressing tumors. These proteins are characterized by a high rate of extravasation and rapid clearance of non-bound tracer from the circulation, as well as other nonspecific compartments, when compared to antibodies and their fragments
== Non-research use == Since ibutamoren is still an Investigational New Drug, it has not yet been approved to be marketed for consumption by humans in the United States. However, it has been used experimentally by some in the bodybuilding community. The use of ibutamoren is banned in most sports.
Many of the former Varian employees now honor Russell Varian's legacy of innovation by funding the Varian Young Investigator Award that recognizes early career investigators in NMR that make significant advancements in instrument development.
Sources: en.wikipedia.org
=== Other uses === The distinctive dried seed heads, which resemble the spouts of watering cans, are widely sold throughout the world for decorative purposes and for dried flower arranging. A unique fabric called lotus silk, from the lotus plant fibres, is produced only at Inle Lake, Myanmar, and in Siem Reap, Cambodia. This thread is used for weaving special robes for Buddha images called kya thingan (lotus robe).
==== Ovulatory cycle ==== In mice, and to a lesser extent in humans, leptin is required for male and female fertility. Ovulatory cycles in females are linked to energy balance (positive or negative depending on whether a female is losing or gaining weight) and energy flux (how much energy is consumed and expended) much more than energy status (fat levels). When energy balance is highly negative (meaning the woman is starving) or energy flux is very high (meaning the woman is exercising at extreme levels, but still consuming enough calories), the ovarian cycle stops and females stop menstruating. Only if a female has an extremely low body fat percentage does energy status affect menstruation. Leptin levels outside an ideal range may have a negative effect on egg quality and outcome during in vitro fertilization. Leptin is involved in reproduction by stimulating gonadotropin-releasing hormone from the hypothalamus.
== Weathering and biodegradion of oils within the marine environment == Environmental UCMs result from highly degraded petroleum hydrocarbons and once formed they can stay largely unchanged in sediments for many years. For example, in 1969 a diesel oil spill contaminated saltmarsh sediment within Wild Harbor River, US; by 1973 only a baseline hump was observed, which remained largely unchanged within the anaerobic sediment for the next 30 years. In a study of the potential for UCM-dominated oil to be further degraded, it was concluded that even using bacteria specifically adapted for complex UCM hydrocarbons in conjunction with nutrient enrichment, biodegradation rates would still be relatively slow. Bacterial degradation of hydrocarbons is complex and will depend on environmental conditions (e.g. aerobic or anaerobic, temperature, nutrient availability, available species of bacteria etc.).
Canada is a country in North America. Its ten provinces and three territories extend from the Atlantic Ocean to the Pacific Ocean and northward into the Arctic Ocean, making it the second-largest country by total area, with the longest coastline of any country. Its border with the United States is the longest international land border. The country is characterized by a wide range of both meteorologic and geological regions. With a population of over 41 million, it has widely varying population densities, with the majority residing in its urban areas and large areas being sparsely populated. Its capital is Ottawa and its three largest metropolitan areas are Toronto, Montreal, and Vancouver. Indigenous peoples have continuously inhabited what is now Canada for thousands of years. Beginning in the 16th century, British and French expeditions explored and later settled along the Atlantic coast. As a consequence of various armed conflicts, France ceded nearly all of its colonies in North America in 1763. In 1867, with the union of three British North American colonies through Confederation, Canada was formed as a federal dominion of four provinces. This began an accretion of provinces and territories resulting in the displacement of Indigenous populations, and a process of increasing autonomy from the United Kingdom. This increased sovereignty was highlighted by the Statute of Westminster, 1931, and culminated in the Canada Act 1982, which severed the vestiges of legal dependence on the Parliament of the United Kingdom.
1. Psychiatric Studies (1902–1906) 2. Experimental Researches (1904–1910) (trans L. Stein and D. Riviere) 3. Psychogenesis of Mental Disease (1907–1914; 1919–1958) 4. Freud and Psychoanalysis (1906–1914; 1916–1930) 5. Symbols of Transformation (1911–1912; 1952) 6. Psychological Types (1921) 7. Two Essays on Analytical Psychology (1912–1928) 8. Structure and Dynamics of the Psyche (1916–1952) 9.1 Archetypes and the Collective Unconscious (1934–1955) 9.2 Aion: Researches into the Phenomenology of the Self (1951) 10. Civilization in Transition (1918–1959) 11. Psychology and Religion: West and East (1932–1952) 12. Psychology and Alchemy (1936–1944) 13. Alchemical Studies (1919–1945) 14. Mysterium Coniunctionis (1955–1956) 15. Spirit in Man, Art, and Literature (1929–1941) 16. The Practice of Psychotherapy (1921–1925) 17. The Development of Personality (1910; 1925–1943) 18. The Symbolic Life: Miscellaneous Writings 19. General Bibliography 20. General Index Supplementary volumes
Sources: en.wikipedia.org
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.
Both are synthetic analogues derived from the same parent hormone. Reference descriptions usually characterise afamelanotide as more selective for the MC1R subtype, whereas melanotan-2 is reported to interact with a wider range of melanocortin receptors.
Early studies explored melanocortin signalling and pigmentation, which later led to informal use of the label tanning peptide. That label is not a regulatory category and does not imply approved status for any purpose.
No regulatory agency has authorised melanotan-2 as a medicine for any indication. It circulates mainly as a research chemical or through unregulated channels. As a result, identity, purity and content are not independently guaranteed.