The short version of eumelanin fits in a sentence. The long version — which is the one that helps — is below.
Reviewed 2025-11-27. Anything still debated is marked as such rather than presented as settled.
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.
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.
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.
Melanotan-2 is a synthetic cyclic heptapeptide designed as a structural analogue of alpha-melanocyte-stimulating hormone, the endogenous tridecapeptide that regulates pigment production. Two modifications distinguish it from the natural hormone: norleucine replaces methionine at the N-terminus, which limits oxidation, and a D-phenylalanine substitution raises receptor affinity. The ring is closed through an aspartate-lysine lactam bridge, giving the molecule a constrained conformation. The free base has a molecular mass near 1024 daltons, and commercial material is usually supplied as an acetate salt. It appears in the literature as a research peptide rather than an approved therapeutic agent.
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.
| Property | Value | Notes |
|---|---|---|
| Common synonyms | Melanotan II; MT-II; N-acetyl-norleucyl-cyclo[Asp-His-D-Phe-Arg-Trp-Lys] amide | Naming follows peptide convention; the numeral distinguishes it from melanotan-1 |
| Molecular formula | C50H69N15O9 | Includes the lactam bridge; no counter-ion assumed |
| Monoisotopic mass | 1023.53 Da | Free base; salts and counter-ions shift the observed value |
| Appearance | White to off-white lyophilised powder | Batch-to-batch colour variation is not itself proof of impurity |
| Typical analytical method | RP-HPLC purity determination with ESI-MS identity confirmation | Retention time alone does not establish sequence identity |
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.
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.
Overall, without considering race, approximately 1.5% of infants born in the United States are carriers of at least one copy of the mutant (disease-causing) gene. In June 2026 it was reported that Daniel Cressy, an African American from Louisiana was cured from the disease after going through curative gene therapy.
Adams (1935), Kafka scholar and professor at the University of California, Los Angeles Frederick Hartt (1935), Michelangelo expert, professor at University of Virginia, member of the Monuments, Fine Arts, and Archives program Herbert Aptheker (1936), Marxist historian and political activist Maurice Matloff (1936), chief historian of the United States Army 1970–1981 John Alexander Moore (1936), professor of zoology at University of California, Riverside Joseph Greenberg (1936), prominent linguist known for work in linguistic typology and genetic classification of languages Carl E. Schorske (1936), cultural historian and winner of the 1981 Pulitzer Prize for History Quentin Anderson (1937), cultural historian and literary critic Charles Frankel (1937), political philosopher, assistant secretary of state for educational and cultural affairs Herbert Hyman (1939), sociologist and expert on opinion polling Herbert E. Klarman (1939), professor of the economics of healthcare at New York University Barry Ulanov (1939), English professor and scholar of jazz and religion Robert J.
=== Switzerland === In Switzerland, the equivalent profession to a clinical biologist is the FAMH Specialist in Laboratory Medicine. This title is awarded by the Foederatio Analyticorum Medicinalium Helveticorum (FAMH), the Swiss organization responsible for the postgraduate training and certification of specialists in medical laboratory diagnostics. To obtain this title, professionals must complete a four-year postgraduate training program, which is carried out alongside employment in an accredited medical laboratory. The program is open to individuals holding a medical degree (MD), a pharmacy degree, or a master’s/PhD in biomedical sciences, biology, or related disciplines. The training covers several specialties, including hematology, clinical chemistry, medical microbiology, immunology, and genetics. The FAMH Specialist in Laboratory Medicine plays a key role in medical diagnostics. They are responsible for the supervision and interpretation of laboratory analyses, validation of results, and communication with clinicians. They also ensure quality management and compliance with ISO 15189 standards, while contributing to the training and supervision of laboratory technical staff. The FAMH Specialist title is federally recognized and is a mandatory requirement to lead and validate medical diagnostic laboratories in Switzerland.
=== Enzyme probes === To investigate enzymatic activity as opposed to total protein, activity-based reagents have been developed to label the enzymatically active form of proteins (see Activity-based proteomics). For example, serine hydrolase- and cysteine protease-inhibitors have been converted to suicide inhibitors. This strategy enhances the ability to selectively analyze low abundance constituents through direct targeting. Enzyme activity can also be monitored through converted substrate. Identification of enzyme substrates is a problem of significant difficulty in proteomics and is vital to the understanding of signal transduction pathways in cells. A method that has been developed uses "analog-sensitive" kinases to label substrates using an unnatural ATP analog, facilitating visualization and identification through a unique handle.
Amitriptyline is supposed to have effect on reducing mast cell degranulation, thus reducing pain and the symptoms associated with mast cell activation, such as IBS pain; people with IBS exhibit increased mucosal mast cells, elevated tryptase/histamine, and enhanced proximity of degranulating mast cells to enteric nerves, each correlating with subjective pain scores. The ability of amitriptyline to have mast-cell stabilizing effects and to reduce subjective pain score are believed to help not simply by altering mood, but by reducing visceral afferent firing, possibly through attenuation of nerve-mast cell crosstalk. Tricyclic antidepressants decrease the frequency, severity, and duration of cyclic vomiting syndrome episodes. Amitriptyline, as the most commonly used of them, is recommended as a first-line agent for its therapy. Amitriptyline may improve pain and urgency intensity associated with bladder pain syndrome and can be used in the management of this syndrome. Amitriptyline can be used in the treatment of nocturnal enuresis in children. However, its effect is not sustained after the treatment ends. Alarm therapy gives better short- and long-term results. In the US, amitriptyline is commonly used in children with ADHD as an adjunct to stimulant medications without any evidence or guideline supporting this practice. Many physicians in the UK (and the US also) commonly prescribe amitriptyline for insomnia; however, Cochrane reviewers were not able to find any randomized controlled studies that would support or refute this practice.
Sources: en.wikipedia.org
== History == The sequence of human GM-CSF was first identified in 1985 and soon three recominbant human GM-CSFs were produced, one in bacteria, one in mammalian cells, and one in yeast; Immunex developed GM-CSF manufactured in yeast into Leukine. Clinical trials of sargramostim were initiated in 1987; in that same year it was administered to six people as part of a compassionate-use protocol for the victims of cesium irradiation from the Goiânia accident. It was approved by the FDA in March 1991, under the brand name Leukine for acceleration of white blood cell recovery following autologous bone marrow transplantation in people with non-Hodgkin's lymphoma, acute lymphocytic leukemia, or Hodgkin's disease. In November 1996, the FDA also approved sargramostim for treatment of fungal infections and replenishment of white blood cells following chemotherapy. A liquid formulation was approved in 1995. Immunex was acquired by Amgen in 2002. As part of the acquisition, Leukine was spun off to Berlex, which became Bayer HealthCare in 2007. In January 2008, Bayer informed healthcare professionals of the market withdrawal of the current liquid formulation of sargramostim. The liquid formulation was withdrawn because of an upward trend in spontaneous reports of adverse reactions, including syncope (fainting), which are temporally correlated with a change that was made to the formulation around April 2007 to include edetate disodium (EDTA). The upward trend in adverse reaction reporting rates had not been observed with the use of lyophilized sargramostim.
Curcumin is a bright yellow chemical produced by the plant species Curcuma longa. It is the principal curcuminoid of turmeric (Curcuma longa), a member of the ginger family, Zingiberaceae. It is sold as an herbal supplement, cosmetics ingredient, food flavoring, and food coloring. Chemically, curcumin is a polyphenol, more particularly a diarylheptanoid, belonging to the group of curcuminoids, which are phenolic pigments responsible for the yellow color of turmeric. Extensive studies have consistently failed to show any medical value for curcumin. It is difficult to study because it is both unstable and poorly bioavailable. It is unlikely to produce useful leads for drug development as a lead compound.
Constipation refers to bowel movements that are infrequent or hard to pass. Constipation is a common cause of painful defecation. Severe constipation includes obstipation (failure to pass stools or gas) and fecal impaction, which can progress to bowel obstruction and become life-threatening.
Systemic amyloidoses affect more than one body organ or system. Examples are AL, AA and Aβ2m. Localised amyloidoses affect only one body organ or tissue type. Examples are Aβ, IAPP, Atrial natriuretic factor (in isolated atrial amyloidosis), and Calcitonin (in medullary carcinoma of the thyroid) Another classification is primary or secondary.
Sources: en.wikipedia.org
=== South Korea === The crisis has not had a dramatic impact on the lives of most South Koreans, and energy minister Kim Sung-hwan has said that the country would not experience problems with supply for over a year. However, the Korean Government launched an energy-saving campaign, encouraging its citizens to have brief showers, and limit their use of washing machines, and it has postponed the decommissioning of coal-fired power plants as well as reducing the limit on electricity made from coal.
Around a dozen police officers, along with judge Claise, searched Kaili's apartment, where she was subsequently arrested. According to reports, Kaili did not resist but appeared "in a state of shock and confusion, crying and terrified." She was then interrogated for more than five hours. The raids also targeted locations connected to Antonio Panzeri, an Italian former MEP. During a search of his home, police found a large quantity of cash in his "well-stocked safe". Simultaneously, investigators raided the offices of the international NGO Fight Impunity, an organisation founded to promote the fight against impunity for serious human rights violations and crimes against humanity, where Panzeri served as president. As a result of the Brussels raids, police arrested several key figures, including Eva Kaili; Antonio Panzeri; Francesco Giorgi, Kaili's life partner and an adviser of the Italian MEP Andrea Cozzolino; Alexandros Kailis, Kaili's father and a former Greek politician; Luca Visentini, the general secretary of the International Trade Union Confederation (ITUC); Niccolò Figà-Talamanca, Secretary-General of the NGO No Peace Without Justice. At Panzeri's home, police reportedly found €600,000 in cash, with additional cash discovered at Kaili's father's home, his hotel room and the residence shared by Kaili and Giorgi. The total cash seized during the raids was €1.5 million. After her arrest, Kaili was detained at the Saint-Gilles Prison before being transferred to Haren Prison five days later.
=== Microanatomy === Determination of the macroscopic structure of the mesenteric organ allowed a recent characterisation of the histological and electron microscopic properties. The microscopic structure of the mesocolon and associated fascia is consistent from ileocecal to mesorectal levels. A surface mesothelium and underlying connective tissue is universally apparent. Adipocytes lobules within the body of the mesocolon are separated by fibrous septa arising from submesothelial connective tissue. Where apposed to the retroperitoneum, two mesothelial layers separate the mesocolon and underlying retroperitoneum. Between these is Toldt's fascia, a discrete layer of connective tissue. Lymphatic channels are evident in mesocolic connective tissue and in Toldt's fascia.
With an increased public awareness and concern regarding radioactive contamination, there has been an increased interest in the development of new pathways for the capture, containment, and disposal of nuclear waste, which has largely been generated through the operation of nuclear power plants and continued decommissioning of nuclear weapons. One of the largest challenges currently recognized within the nuclear waste sector is the development and synthesis of novel materials capable of long-term containment and selective capture of actinides. Thus, metal-organic frameworks have emerged as a promising material towards this application; their remarkable modularity, high surface area, selective binding affinities, and customizable topology/crystallinity allow for a material with tunable, on-demand properties and high structural stability. These properties allow for the design of a framework that connects material properties with changes in structure at the atomic level, providing insight into the processes that these materials rely upon. For example, metal-organic frameworks tend to have high structural stability, as evidenced by their crystallinity. This has been applied towards nuclear waste by demonstrating that metal-organic frameworks, specifically a zirconium-based framework, resist prolonged exposure to gamma-rays, a deeply penetrating, hazardous form of radiation known to be emitted by radioactive substances such as 241Am, while retaining crystallinity. There are several known methods by which metal-organic frameworks have been used to sequester radionuclides.
=== Other bodies in exile === Other Grand Lodges were created for the Cuban exile community, including the United Grand Lodge of the Antilles (Spanish: Gran Logia Unida de las Antillas), and the Most Serene Grand Lodge (Spanish: Serenisima Gran Logia), and the Cuba First Federation of Cuban Masons in Exile (Spanish: Federacion de Masones Cubanos Cuba Primero).
Sources: en.wikipedia.org
It is a synthetic cyclic heptapeptide analogue of alpha-melanocyte-stimulating hormone, containing seven amino acids with a lactam ring and a D-configured phenylalanine residue. It is supplied as a lyophilised powder for laboratory research.
The natural hormone is a linear tridecapeptide that is rapidly degraded in circulation. Melanotan-2 is shortened, cyclised, N-terminally acetylated, and carries a D-amino acid substitution, all of which slow enzymatic breakdown.
No national medicines regulator has approved melanotan-2 for therapeutic or cosmetic use. In several jurisdictions it is treated as an unapproved prescription medicine, and its legal classification differs from country to country.
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.