Everything below concerns cyclic heptapeptide. We keep the language plain, cite what the science says, and separate well-supported claims from open questions.
Last reviewed on 2026-08-01. Where a claim depends on a specific study, the study is described rather than over-claimed.
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.
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.
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.
| 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.
Biohazardous safety issues are identified with specified labels, signs and paragraphs established by the American National Standards Institute (ANSI). Today, ANSI Z535 standards for biohazards are used worldwide and should always be used appropriately within ANSI Z535 Hazardous Communications (HazCom) signage, labeling and paragraphs. The goal is to help workers rapidly identify the severity of a biohazard from a distance and through colour and design standardization. Biological hazard symbol design:
Team Fortress Classic is a 1999 first-person shooter game developed by Valve and published by Sierra Studios. It was originally released in April 1999 as a mod for Valve's 1998 Windows game Half-Life, and is based on Team Fortress, a mod for the 1996 game Quake. In Team Fortress Classic, two teams compete in online multiplayer matches. Players choose one of nine classes, each with different skills. The scenarios include capture the flag, territorial control, and escorting a "VIP" player. Valve hired the developers of the Team Fortress mod to develop Team Fortress Classic. It received generally positive reviews, although the graphics were a point for criticism. In 2000, Valve released a standalone version, Team Fortress 1.5, with new character models, maps and other features. Team Fortress 2 was released in 2007.
== External links == Clinical trial number NCT02715258 for "Safety and Efficacy of Bexagliflozin as Monotherapy in Patients With Type 2 Diabetes" at ClinicalTrials.gov Clinical trial number NCT03259789 for "Safety and Efficacy of Bexagliflozin Compared to Placebo as Add-on Therapy to Metformin in Type 2 Diabetes Subjects" at ClinicalTrials.gov Clinical trial number NCT02769481 for "Safety and Efficacy of Bexagliflozin Compared to Glimepiride as Add-on Therapy to Metformin in Type 2 Diabetes Subjects" at ClinicalTrials.gov Clinical trial number NCT03115112 for "Safety and Efficacy of Bexagliflozin Compared to Sitagliptin as Add-on Therapy to Metformin in Type 2 Diabetes Subjects" at ClinicalTrials.gov Clinical trial number NCT02836873 for "Safety and Efficacy of Bexagliflozin in Type 2 Diabetes Mellitus Patients With Moderate Renal Impairment" at ClinicalTrials.gov Clinical trial number NCT02558296 for "Bexagliflozin Efficacy and Safety Trial (BEST)" at ClinicalTrials.gov
And you do not set 2,000 tanks and 20,000 men in motion within 48 hours." On 31 August 2008, Matthew Bryza stated at Bled Strategic Forum in Slovenia that the United States had actively been working to prevent Georgia from responding to South Ossetian attacks. In August 2008, Vadim Kozaev, employee of Ministry of Internal Affairs of North Ossetia–Alania, and his brother Vladislav Kozaev, hero of Abkhazia and South Ossetia, alleged that Eduard Kokoity, the president of South Ossetia, knew in advance that the war was coming and fled Tskhinvali.
== Screening and diagnosis == Screening for VRE can be done in several ways. For inoculating peri-rectal/anal swabs or stool specimens directly, one method uses bile esculin azide agar plates containing 6 μg/ml of vancomycin. Black colonies should be identified as an enterococcus to species level and further confirmed as vancomycin resistant by an MIC method before reporting as VRE. Vancomycin resistance can be determined for enterococcal colonies available in pure culture by inoculating a suspension of the organism onto a commercially available brain heart infusion agar (BHIA) plate containing 6 μg/ml vancomycin. The Clinical and Laboratory Standards Institute (CLSI) recommends performing a vancomycin MIC test and also motility and pigment production tests to distinguish species with acquired resistance (vanA and vanB) from those with vanC intrinsic resistance. Detection of vancomycin resistance by the use of PCR targeting vanA and vanB can also be performed. Once the individual has VRE, it is important to ascertain which strain.
Sources: en.wikipedia.org
The findings of biochemistry are applied primarily in medicine, nutrition, and agriculture. In medicine, biochemists investigate the causes and cures of diseases. Nutrition studies how to maintain health and wellness and also the effects of nutritional deficiencies. In agriculture, biochemists investigate soil and fertilizers with the goal of improving crop cultivation, crop storage, and pest control. In recent decades, biochemical principles and methods have been combined with problem-solving approaches from engineering to manipulate living systems in order to produce useful tools for research, industrial processes, and diagnosis and control of disease—the discipline of biotechnology.
==== Metabolism ==== The metabolism of oxycodone in humans occurs in the liver mainly via the cytochrome P450 system and is extensive (about 95%) and complex, with many minor pathways and resulting metabolites. Around 10% (range 8–14%) of a dose of oxycodone is excreted essentially unchanged (unconjugated or conjugated) in the urine. The major metabolites of oxycodone are noroxycodone (70%), noroxymorphone ("relatively high concentrations"), and oxymorphone (5%). The immediate metabolism of oxycodone in humans is as follows:
Nausea Bone marrow suppression, including Decreased white blood cell count causing increased risk of infection Decreased platelet count causing increased risk of bleeding Less common side effects include:
These N-methyltryptamines are much more lipophilic than serotonin and, in contrast, are able to diffuse into serotonergic neurons and activate intracellular serotonin 5-HT2A receptors. Another metabolite of serotonin with possible psychedelic-like effects in animals is 5-methoxytryptamine (5-MT). DMT is a naturally occurring endogenous compound in the body. In relation to the fact that serotonin itself is unable to activate intracellular serotonin 5-HT2A receptors, it is possible that DMT might be the endogenous ligand of these receptors rather than serotonin.
Sources: en.wikipedia.org
== Immunomodulation == In addition to killing bacteria directly they have been demonstrated to have a number of immunomodulatory functions that may be involved in the clearance of infection, including the ability to alter host gene expression, act as chemokines and/or induce chemokine production, inhibiting lipopolysaccharide induced pro-inflammatory cytokine production, promoting wound healing, and modulating the responses of dendritic cells and cells of the adaptive immune response. Animal models indicate that host defense peptides are crucial for both prevention and clearance of infection. It appears as though many peptides initially isolated as and termed "antimicrobial peptides" have been shown to have more significant alternative functions in vivo (e.g. hepcidin). Dusquetide for example is an immunomodulator that acts through p62, a protein involved in toll like receptor based signalling of infection. The peptide is being examined in a Phase III clinical trial by Soligenix (SGNX) to ascertain if it can assist in repair of radiation-induced damage to oral mucosa arising during cancer radiotherapy of the head and neck.
=== Diseases === P. somniferum is susceptible to several fungal, insect and virus infections including seed borne diseases such as downy mildew and root rot. The use of pesticides in combination to cultural methods have been considered as major control measures for various poppy diseases. The fungal pathogen Peronospora arborescens, the causal agent of downy mildew, occurs preferentially during wet and humid conditions. This oomycete penetrates the roots through oospores and infects the leaves as conidia in a secondary infection. The fungus causes hypertrophy and curvature of the stem and flower stalks. The symptoms are chlorosis and curling of the affected tissues with necrotic spots. The leaf under-surface is covered with a downy mildew coating containing conidiospores that spread the infection further leading to plant damage and death. Another downy mildew species, Peronospora somniferi, produces systemic infections leading to stunting and deformation of poppy plants. Downy mildew can be controlled preventively at the initial stage of seed development through several fungicide applications. Leaf blight caused by the fungus Helminthosporium papaveris is one of the most destructive poppy diseases worldwide. The seed-borne fungus causes root rot in young plants and stunted stems in plants at a higher development stage, where leaf spots appear on the leaves and is being transmitted to capsules and seeds.
The country was the second-largest producer of pulp in the world and the eighth-largest producer of paper in 2016. In the footwear industry, Brazil was the fourth-largest producer in 2019. It was also the ninth-largest producer of steel in the world. In 2018, the chemical industry of Brazil was the eighth-largest in the world. Although it was among the five largest world producers in 2013, Brazil's textile industry is very little integrated into world trade. The tertiary sector (trade and services) represented 75.8% of the country's GDP in 2018, according to the IBGE. The service sector was responsible for 60% of GDP and trade for 13%. It covers commerce, transport, education, social and health services, research and development, sports activities, etc. Micro and small businesses represent 30% of the country's GDP. In the commercial sector they represent 53% of the GDP within the activities of the sector.
Neuroleptic, originating from the Ancient Greek terms νεῦρον ('neuron') and λαμβάνω ('to take hold of')—thus meaning 'which takes the nerve'—refers both to common neurological effects and to side-effects. An estimated 1.7% of adults in the United States take antipsychotics, according to a 2018 study.
== Medical uses == Thiotepa is used in combination with other chemotherapy agents to treat cancer. It can be given with or without total body irradiation (TBI) to prepare the body for allogeneic or autologous hematopoietic progenitor cell transplantation (HPCT), which replaces damaged blood-forming cells with donor cells. This treatment is used in both adults and children for blood cancers such as Hodgkin lymphoma and leukemia. Thiotepa is also used with high-dose chemotherapy and HPCT support to treat certain solid tumors in adults and children. Thiotepa is used in palliative care for several types of cancer, including breast cancer, ovarian cancer, papillary thyroid cancer, and bladder cancer. It is also used to control intracavitary effusions caused by serosal neoplastic deposits, which refers to fluid buildup resulting from cancer spreading to the lining of body cavities. In Japan, a widely used regimen consisting of high-dose thiotepa and melphalan, followed by autologous peripheral blood stem cell rescue, is used to treat high-risk neuroblastoma.
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.