Comparison
Afamelanotide vs. Humanin
Two peptides side-by-side — identity, evidence base, legal status and known adverse events.
Identity
Category
Research other
Research other
CAS no.
75921-69-6
330936-69-1
Molecular weight
1646.87 g/mol
2687.27 g/mol
Half-life
12 h
no data
Sequence
Ac-Ser-Tyr-Ser-Nle-Glu-His-D-Phe-Arg-Trp-Gly-Lys-Pro-Val-NH2Met-Ala-Pro-Arg-Gly-Phe-Ser-Cys-Leu-Leu-Leu-Leu-Thr-Ser-Glu-Ile-Asp-Leu-Pro-Val-Lys-Arg-Arg-AlaMechanism of action
Afamelanotide
Afamelanotide is a synthetic analogue of α-melanocyte-stimulating hormone. It differs from native α-MSH by two substitutions — norleucine at position 4 and D-phenylalanine at position 7 — which make it metabolically more stable and more potent. As an agonist at the melanocortin-1 receptor (MC1R) on melanocytes, it activates adenylate cyclase, raises cAMP and increases tyrosinase activity via the transcription factor MITF. This shifts pigment synthesis toward eumelanin, which absorbs UV and visible light and has antioxidant properties — the presumed mechanism of photoprotection in EPP.
Humanin
Humanin arises from a short open reading frame within the 16S rRNA region of the mitochondrial genome (MT-RNR2) — it is therefore not encoded by nuclear DNA. Mechanistically, preclinical work describes a cytoprotective, anti-apoptotic effect via multiple pathways: an extracellular interaction with a trimeric receptor complex of gp130, CNTFR and WSX-1 with downstream activation of JAK2/STAT3 signalling, as well as intracellular interactions including inhibition of the pro-apoptotic protein BAX (and of tBID), binding to IGFBP-3 with modulation of the IGF-1 axis, and interaction with FPRL1/FPRL2 receptors. These models derive predominantly from cell culture and rodents; the extent to which they reflect human physiology after administration of exogenous synthetic humanin is not established by controlled human trials.
Evidence base
Highest evidence
Human RCT
Human trial
Studies
4
4
of which in humans
4
1
Effects recorded
4
4
Open conflicts
1
1
Documented adverse events
4
0
Legal status
Full entries
Frequently asked questions
- What is the difference between Afamelanotide and Humanin?
- Afamelanotide is classified as "Research other", while Humanin is classified as "Research other". Afamelanotide: Afamelanotide (brand name Scenesse) is a synthetic 13-amino-acid analogue of α-melanocyte-stimulating hormone (α-MSH) and a melanocortin-1 receptor agonist. Unlike most peptides covered here, it is a regularly approved medicine: EMA approval in 2014/2015, FDA approval in 2019, in each case as a subcutaneous implant for the prevention of phototoxicity in adults with erythropoietic protoporphyria (EPP). It promotes eumelanin formation in the skin. Humanin: Humanin is a 24-amino-acid mitochondrial-encoded peptide (mitochondrial-derived peptide, MDP) whose open reading frame lies within the 16S rRNA region (gene MT-RNR2) of mitochondrial DNA. It is considered the founding member of the MDP family and was discovered in 2001 by the Hashimoto/Nishimoto group while searching for neuroprotective factors in the brain of an Alzheimer's patient. In basic research (including the laboratory of Pinchas Cohen) humanin is described as a cytoprotective, anti-apoptotic peptide and is studied in the contexts of Alzheimer's/neuroprotection, metabolism/insulin action and aging. The evidence comes almost entirely from cell and animal models and from observations of endogenous levels in humans; controlled human trials of exogenous humanin as a therapeutic are lacking. It is not approved as a medicine anywhere and is traded on the grey market as a research chemical. This page contrasts both neutrally and source-based — with no usage or dosing recommendation.
- Which peptide is better supported by science, Afamelanotide or Humanin?
- The highest available evidence level is "Human RCT" for Afamelanotide and "Human trial" for Humanin. A higher evidence level means more robust data, but says nothing about suitability for an individual. The full body of evidence is on each peptide's own page.
- What is the legal status of Afamelanotide and Humanin in Germany and the United States?
- Germany: Afamelanotide — Prescription, Humanin — Unapproved. United States: Afamelanotide — Prescription, Humanin — Research only. These are factual summaries with source and review date on the individual pages.