Melanotan 2 Spray 10 mg

One-Peptides MELANOTAN 2 10 mg — an α-MSH analogue in a nasal spray for laboratory research

MELANOTAN 2 10 mg in a nasal spray is a research reagent (Research Use Only) in the form of a pre-dissolved solution. Melanotan 2 (MT-2) is not authorised as a medicine in any major jurisdiction (EMA, FDA). It is a synthetic analogue of α-MSH intended solely for laboratory research into the pharmacology of melanocortin receptors. It is not a cosmetic product, a tanning agent, a supplement or a product for human use. The related, authorised melanocortin analogues (afamelanotide, bremelanotide) are distinct molecules with their own narrow medical indications — they are not identical to MT-2.

Melanotan 2 is one of the most extensively documented synthetic analogues of the melanotropic hormone α-MSH (alpha-melanocyte-stimulating hormone) in the literature. The molecule was developed at the University of Arizona during the 1980s and 1990s as part of the work of the teams of Victor Hruby and Mac Hadley on the pharmacology of pigmentation. MT-2 is a non-selective agonist of melanocortin receptors — it binds and activates the MC1R, MC3R, MC4R and MC5R receptors, which makes it a valuable tool for studying the entire family of these receptors.

In the One Peptides catalogue, Melanotan 2 functions as a RUO chemical reagent in a nasal spray format, that is, a pre-dissolved solution with a spray applicator. This format organises work around one specific research question — the intranasal route of administration. The nasal mucosa is an area under intensive study as an alternative route for introducing peptides, including in the context of nose-to-brain transport (the nasal–brain axis). The spray does not require reconstitution of a lyophilisate and allows the solution to be dosed reproducibly onto the mucosal surface in experimental models — this is a technical solution for researchers, not a dosage form for administration to humans.

Melanotan 2 (MT-2) is a cyclic, synthetic analogue of the α-MSH hormone and a non-selective agonist of the MC1R/MC3R/MC4R/MC5R melanocortin receptors, with the sequence Ac-Nle-cyclo[Asp-His-D-Phe-Arg-Trp-Lys]-NH₂. In the One Peptides catalogue it is supplied as a pre-dissolved Research Use Only reagent in a nasal spray, intended solely for laboratory research into the pharmacology of melanocortins.

What Melanotan 2 is — sequence and class

Melanotan 2 is a cyclic α-MSH analogue — a synthetic peptide designed as a more stable and more potent counterpart of the natural melanotropic hormone. Natural α-MSH has a very short serum half-life (minutes); cyclisation and amino-acid substitutions in MT-2 extend its stability and increase its affinity for melanocortin receptors.

Sequence: Ac-Nle-cyclo[Asp-His-D-Phe-Arg-Trp-Lys]-NH₂ — a cyclic heptapeptide core with a D-phenylalanine residue and a lactam bridge stabilising the conformation. These modifications account for its resistance to enzymatic degradation and its high receptor activity towards α-MSH.

Chemical characteristics

Mechanism of action in research

Melanotan 2 activates the melanocortin receptor family — G protein-coupled receptors whose stimulation increases the intracellular concentration of cAMP. The individual subtypes are responsible for different physiological effects studied in the literature.

1. MC1R — melanogenesis. The MC1R receptor on the surface of melanocytes regulates eumelanin synthesis. Activation of MC1R triggers the cAMP → MITF → tyrosinase pathway, leading to the production of dark pigment. In cell and animal models, MT-2 stimulates melanogenesis more strongly than native α-MSH — this is the basis for using MT-2 as a tool for studying pigmentation at the receptor level.
2. MC4R — central signalling. The MC4R receptor in the central nervous system participates in the regulation of appetite, energy expenditure and pathways related to sexual function. It was on the basis of selectively stimulating MC4R that a separate, authorised molecule was developed — bremelanotide. In research, MT-2 serves as a reference agonist for this receptor.
3. MC3R and MC5R. MC3R contributes to the regulation of energy homeostasis and inflammatory processes; MC5R is associated with the function of exocrine glands. The non-selectivity of MT-2 means that it stimulates all four subtypes — which is an advantage in studies of the entire receptor family and a limitation where selectivity for a single subtype is required.

The reference data on MT-2 come mainly from cell models (melanocyte lines), animal models of pigmentation and early pharmacological studies of the melanocortin system.

The nasal spray format — research context

The nasal spray is a reagent form oriented towards one specific area of science: the intranasal administration of peptide compounds. The mucous membrane of the nasal cavity is well vascularised and directly accessible, and its connection with the olfactory bulb has long been analysed as a potential route for transporting molecules to the central nervous system while bypassing the blood–brain barrier (the nose-to-brain axis). For this reason, the intranasal route is an attractive direction for centrally active peptides, and MT-2 — as a melanocortin agonist acting, among other things, on MC4R and MC3R in the CNS — is sometimes considered a model molecule in such work.

This must, however, be stated plainly. For intranasal administration, Melanotan 2 lacks robust clinical data. The well-documented pharmacokinetic and pharmacodynamic studies of MT-2 in humans were based on subcutaneous (injectable) administration; it is from this work that the known absorption and half-life parameters derive. Intranasal use of MT-2, by contrast, exists mainly in the recreational sphere and remains poorly studied — there are no reliable clinical data confirming the bioavailability, kinetics or safety of this route for this molecule. The nasal spray format should therefore be treated as a tool for research into the intranasal administration of MT-2, not as a validated method of delivering the peptide. Any conclusion regarding the intranasal absorption of MT-2 requires separate experimental verification.

Melanotan 2 (RUO) versus authorised melanocortin analogues

Conceptual confusion has grown up around MT-2 because molecules authorised as medicines also derive from melanocortin chemistry. These are, however, distinct substances with a distinct status.

Melanotan 2 is none of the authorised melanocortin medicines. Afamelanotide and bremelanotide are different molecules, with a different selectivity profile, authorised for narrow, specific indications under medical supervision. MT-2 as a RUO reagent has no status as a medicinal product and is not intended for any human use — regardless of the form in which it is supplied.

Applications in scientific research

Melanotan 2 as a RUO reagent finds application in several directions.

Pharmacology of melanocortin receptors. Analyses of the receptor activity of the four MCR subtypes, EC50 measurements in cell cultures with cAMP reporters, profiling of agonists and comparisons with selective ligands. The non-selectivity of MT-2 makes it a useful reference agonist for the entire family.

Melanogenesis research. Cell models of melanocytes and melanoma lines (B16) for studying the tyrosinase/MITF pathway, the regulation of eumelanin synthesis and the pigmentary response to MC1R agonists.

Models of central energy regulation. Research into the role of MC4R and MC3R in energy homeostasis, appetite and energy expenditure — MT-2 as a tool for stimulating melanocortin pathways in animal models.

Research into intranasal administration. The spray format allows analysis of the behaviour of a melanocortin peptide on the nasal mucosa and in nose-to-brain transport models, in work on alternative routes for delivering centrally active molecules — with the caveat that there are no validated clinical data for this route.

One Peptides quality specification

Every Melanotan 2 spray undergoes a five-stage analytical control process.

• HPLC ≥98% — the area of the main peak is ≥98% of the sum of areas (liquid chromatography with UV detection).
• MS confirmation — confirmation of the peptide’s identity by molecular weight (~1024 Da).
• COA per batch — a public certificate of analysis for each batch (theoretical/measured mass, HPLC profile, date of synthesis, batch number).
• Cold chain 2–8°C — a monitored cold chain from synthesis to delivery.
• Batch traceability — the batch number in three places: the spray label, the invoice and the COA.

Safety and limitations in the light of research

Melanotan 2 is a pharmacologically active substance with a broad, non-selective profile of action on melanocortin receptors. The literature and reports document a range of effects relevant to risk awareness when working with the reagent:

• Darkening of naevi and freckles. Stimulation of MC1R intensifies melanogenesis not only in the skin generally but also in existing pigmented naevi — enlargement and darkening of pigmented lesions has been documented. This raises justified oncological vigilance: case reports of melanoma and dysplastic lesions in the context of MT-2 use in humans have appeared in the literature. A causal link has not been established, but the signal calls for caution.
• Nausea and facial flushing — frequently reported effects of melanocortin activation, particularly on first exposure.
• Spontaneous erections — a consequence of MC4R stimulation; this is the same mechanism on which the selective medicine bremelanotide is based.
• Reduced appetite — a result of central action on MC4R/MC3R.
• No data for the intranasal route. The profile of MT-2 is known from injectable studies; the bioavailability and safety of intranasal administration of this molecule remain clinically unstudied.
• No authorisation and no long-term data. MT-2 has not undergone full marketing-authorisation studies — its long-term safety profile in humans remains undetermined.

In addition, MT-2 is light-sensitive — the solution is stored protected from UV exposure, and cloudiness, sediment or a change in colour is a signal that the batch is no longer suitable for further work. This information is scientific and cautionary in nature and concerns risk awareness, not instructions for use. Working with MT-2 in a research setting requires the standard precautions for biologically active peptides.

Regulatory status and WADA

Melanotan 2 (this product) — a Research Use Only research reagent within the EU chemical reagent supply. The label reads “For research use only. Not for human use”. It is not a medicinal product, a cosmetic, a dietary supplement or a foodstuff. It holds no EMA or FDA authorisation.

The authorised melanocortin analogues are different molecules: afamelanotide (Scenesse, MC1R, EPP) and bremelanotide (Vyleesi, MC4R, HSDD) — with their own narrow indications and medical supervision. Medicinal status belongs solely to them, not to MT-2.

WADA. Melanotan 2 does not appear as a separate entry on the current WADA prohibited list. This status may change in subsequent editions, and the general clauses concerning biologically active substances require independent verification on the part of the researcher.

Frequently asked questions

How does Melanotan 2 differ from the melanocortin medicines (Scenesse, Vyleesi)?
They are distinct molecules. Melanotan 2 is a non-selective agonist of all four melanocortin receptors and holds RUO reagent status. Afamelanotide (Scenesse) acts mainly on MC1R and is authorised for erythropoietic protoporphyria; bremelanotide (Vyleesi) acts mainly on MC4R and is authorised for HSDD. MT-2 is not identical to either of them and has no status as a medicine.

Is Melanotan 2 a tanning agent?
No. It is a chemical reagent for laboratory research into the pharmacology of melanocortin receptors and melanogenesis. It is not a cosmetic product or a tanning agent and is not intended for human use — regardless of the form in which it is supplied.

Why is MT-2 called non-selective?
Because it activates all four subtypes of melanocortin receptors (MC1R, MC3R, MC4R, MC5R), unlike ligands designed to stimulate a single subtype. Non-selectivity is an advantage in studies of the entire receptor family and a limitation where selectivity is required.

What is the molecular formula and weight of Melanotan 2?
The molecular formula is C₅₀H₆₉N₁₅O₉, with a molecular weight of about 1024.2 Da. The molecule is a cyclic α-MSH analogue with the sequence Ac-Nle-cyclo[Asp-His-D-Phe-Arg-Trp-Lys]-NH₂. The identity of each batch is confirmed by mass spectrometry.

How long does the solution remain stable after opening?
Unopened spray: typically up to 24 months at 2–8°C, protected from light (details in the batch COA). After first opening: typically up to 28 days at 2–8°C. MT-2 is light-sensitive, so the solution should be protected from UV exposure; freeze–thaw cycles should be avoided.

Bibliography

1. Hadley ME, Hruby VJ et al. (2002). Discovery and development of novel melanogenic drugs
2. Dorr RT et al. (1996). Evaluation of melanotan-II, a superpotent cyclic melanotropic peptide in a pilot phase-I clinical study
3. Wessells H et al. (2000). Effect of an alpha-melanocyte stimulating hormone analog on penile erection and sexual desire

Melanotan 2 10 mg in a nasal spray in the One Peptides catalogue is not a medicinal product, a cosmetic, a dietary supplement or a foodstuff. It is not intended for administration to humans or animals outside a controlled experimental setting, nor for any application in tanning, skin pigmentation or the modulation of sexual function in humans. Melanotan 2 holds no EMA or FDA authorisation as a medicine. The authorised melanocortin analogues (afamelanotide, bremelanotide) are distinct molecules with a distinct status. The information in this description is educational and scientific in nature and refers to results reported in the literature — it does not constitute medical or cosmetic advice or instructions for administration.