Melanogenesis Research Peptide (MT-II) Scientific Profile

Product Overview: Melanotan II (MT-II)

Melanotan II (MT-II) is a synthetic analog of the naturally occurring melanocortin peptide, $\alpha$-Melanocyte-Stimulating Hormone ($\alpha$-MSH). This cyclic heptapeptide is recognized as a primary pharmacological tool for investigating the complex biochemical pathways governing melanogenesis—the process of producing melanin pigment in the skin. Its potent and selective binding capabilities make it an invaluable agent in dermatological and pharmacological research aimed at understanding skin pigmentation, photoprotection, and the functions of the melanocortin system.

Scientific Mechanism and Activity

Melanotan II acts as a potent, non-selective agonist of the melanocortin receptors (MCRs), specifically exhibiting a high affinity for the Melanocortin-1 Receptor (MC1R), the Melanocortin-3 Receptor (MC3R), and the Melanocortin-4 Receptor (MC4R).

Melanocortin-1 Receptor (MC1R) Agonism

The primary research focus for MT-II centers on its interaction with the MC1R, which is highly expressed on melanocytes in the skin.

• Mechanism: When MT-II binds to the MC1R, it initiates a cascade of intracellular signaling events. This binding leads to the activation of adenylyl cyclase, which increases intracellular levels of cyclic adenosine monophosphate (cAMP). Elevated cAMP is the central signaling molecule that drives the melanogenesis process.
• Melanin Synthesis Upregulation: The increase in cAMP activates the Microphthalmia-associated Transcription Factor (MITF). MITF is the master regulator of melanogenesis, controlling the expression of key pigment-producing enzymes, including tyrosinase, TRP-1 (Tyrosinase-Related Protein 1), and TRP-2 (Dopachrome Tautomerase).

Eumelanin vs. Pheomelanin Investigation

The type of melanin produced is genetically determined and influenced by the activity of the MC1R. MT-II research is often directed at determining its role in promoting the synthesis of the protective dark pigment.

• Eumelanin: This is the brown/black pigment, which is highly effective at absorbing and scattering ultraviolet (UV) radiation. Potent MC1R activation, as achieved by MT-II, biases the melanogenesis pathway toward the production of eumelanin.
• Pheomelanin: This is the red/yellow pigment, which offers minimal photoprotection and may even contribute to oxidative stress upon UV exposure. MT-II research explores the regulatory mechanisms that suppress pheomelanin production in favor of eumelanin.

Photoprotection Research

One of the most significant research applications of MT-II is the study of "sunless tanning" mechanisms and their potential dermatological benefits.

• UV-Induced DNA Damage: The research hypothesis is that by inducing a sustained, eumelanin-rich tan without direct UV exposure, the skin cells are pre-protected from the DNA damage and mutations typically caused by UV radiation.
• Experimental Model: MT-II serves as a tool to investigate the protective role of increased melanin density (tanning) against acute and chronic UV exposure in various in vitro and in vivo models.

[A detailed diagram illustrating the Melanocortin-1 Receptor (MC1R) signaling pathway within a melanocyte, showing the binding of MT-II, the resulting activation of adenylyl cyclase and cAMP, and the subsequent upregulation of MITF and melanin-producing enzymes.]

Ideal Applications

Melanotan II is an essential component for specific types of biological assays:

• Dermal Tissue Culture: Used to stimulate melanogenesis in primary human melanocyte cultures or co-cultures with keratinocytes for studying cell-to-cell signaling and pigment transfer.
• Pigmentation Assays: Essential for dose-response studies measuring melanin content, tyrosinase activity, and gene expression changes in response to MC1R agonism.
• Receptor Function Studies: Used to characterize the binding affinity and functional selectivity of the melanocortin receptor family.

Research Area

Primary Focus

Assay Type

Pigment Biology

Eumelanin induction and control

Melanin quantification assay

Photodermatology

UV protection mechanisms

Cell viability and DNA damage assays

Receptor Pharmacology

MC1R binding and signaling

Radioligand binding assays

Chemical and Storage Details

Attribute

Detail

Chemical Name

Melanotan II

Molecular Formula

$C_{50}H_{69}N_{15}O_{10}$

Molecular Weight

$1085.24$ g/mol

Purity

$\ge 98%$ (HPLC)

Reconstitution and Handling

MT-II is typically shipped as a lyophilized powder. For research purposes, it is generally reconstituted in bacteriostatic water or a sterile solvent.

• Storage (Lyophilized): Store at $-20^\circ C$ (Freezer).
• Storage (Reconstituted): Store at $2^\circ C$ to $8^\circ C$ (Refrigerated) for short-term use, or $-20^\circ C$ for long-term storage, protected from light.

Status and Warning

Status: Experimental Reagent.

WARNING: Melanotan II is sold strictly for in vitro laboratory research use only. It is not intended for human consumption, diagnostic, therapeutic, or veterinary use. All handling and disposal must comply with institutional safety protocols. Researchers must be trained in laboratory chemical handling.

Related Resources

Please refer to the following documents and materials for detailed experimental protocols:

• Melanotan II Safety Data Sheet (SDS): File
• Standard Operating Procedure (SOP) for Melanocyte Culture: File
• MC1R Signaling Pathway Review: [A scientific review article on the MC1R signaling pathway]

For scheduling a consultation regarding experimental design, please contact Person at the Research Support Office. Calendar event