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Research Only Immune & Anti-Inflammatory

Alpha-MSH

also known as: α-MSH, Alpha-Melanocyte Stimulating Hormone, α-Melanotropin

The endogenous anti-inflammatory melanocortin — the 13-amino-acid POMC fragment that PT-141, melanotan, setmelanotide, and the entire melanocortin drug class are built on.

A tridecapeptide cleaved from pro-opiomelanocortin (POMC) in the pituitary and skin, activating melanocortin-1 receptor (MC1R) to drive melanogenesis and producing potent anti-inflammatory effects via NF-κB suppression in immune cells.

Mechanism of action

Agonist at MC1R (melanocortin-1 receptor) on melanocytes (stimulates melanin production), immune cells (suppresses NF-κB, reduces TNF-α/IL-1β/IL-6, promotes IL-10), and keratinocytes. The His-Phe-Arg-Trp tetrapeptide core is the pharmacophore shared by all melanocortin drugs. Also acts at MC3R and MC5R with lower affinity. Central MC4R activation (by analogs) mediates appetite suppression and sexual arousal.

Primary uses

  • Melanocortin signaling research
  • Anti-inflammatory pathway studies
  • Parent molecule for melanocortin drug design
  • UV protection and pigmentation research

Typical dosing

Not established

Research reagent. Therapeutic activity delivered via stabilized analogs (afamelanotide, PT-141, setmelanotide).

Regulatory status

Not approved as a therapeutic. Parent molecule for afamelanotide (Scenesse, FDA-approved for EPP), setmelanotide (Imcivree, approved for genetic obesity), PT-141 (Vyleesi, approved for HSDD), and melanotan II (research/grey market).

References

  1. [review] Catania A, et al. "The melanocortin system in control of inflammation." ScientificWorldJournal, 2010;10:1840-1853.
  2. [review] Brzoska T, et al. "Alpha-melanocyte-stimulating hormone and related tripeptides: biochemistry, antiinflammatory and protective effects in vitro and in vivo." Endocr Rev, 2008;29:581-602.

Related peptides

PT-141

An FDA-approved melanocortin agonist for acquired, generalized hypoactive sexual desire disorder in premenopausal women.

Melanotan II

An unapproved cyclic heptapeptide melanocortin agonist marketed for tanning and sexual function — strongly associated with melanocytic changes and dysplastic nevi in case reports. Not recommended.

Afamelanotide

An FDA-approved selective MC1R agonist marketed as Scenesse — the first-in-class treatment for erythropoietic protoporphyria (EPP), delivered as a subdermal implant.

Setmelanotide

Rhythm Pharmaceuticals' Imcivree — the first and only FDA-approved MC4R agonist. Indicated for obesity due to POMC, PCSK1, or LEPR deficiency (2020) and Bardet-Biedl syndrome (2022). Restores downstream MC4R signaling when upstream leptin-melanocortin pathway components are genetically deficient.

KPV

A tripeptide derived from α-MSH with potent anti-inflammatory activity — studied in preclinical models of IBD, psoriasis, and acne.
Disclaimer

This entry is for educational purposes only and does not constitute medical advice. Dosing information reflects published regulatory or research data and is not a recommendation. Many compounds described here are not approved for human use in the United States. Consult a licensed medical professional before considering any peptide therapy.