A synthetic analog of alpha-melanocyte-stimulating hormone that stimulates melanogenesis, increasing skin pigmentation and providing photoprotection against UV radiation.
Khong. K K; Kurtz. S E SE; Sykes. R L RL; Cone. R D RD
This study shows that a specific brain cell line (GT1-1) naturally makes the MC4‑R receptor, which reacts to the melanotan‑I peptide (NDP‑α‑MSH). When the peptide binds, the cells raise cAMP levels and release the hormone GnRH, an effect that can be blocked by the natural antagonist AGRP. The work is a basic lab finding, not a human trial, but it confirms that melanotan‑I can directly activate MC4‑R in hypothalamic cells and may influence appetite‑related and reproductive pathways.
In goldfish, the appetite‑suppressing effect of the peptide melanotan II (a synthetic version of alpha‑MSH) depends on another hormone called corticotropin‑releasing hormone (CRH). Blocking CRH receptors stopped melanotan II from reducing food intake, while blocking the melanocortin‑4 receptor did not affect CRH’s own appetite‑suppressing action. The study also showed that brain cells that make alpha‑MSH are physically close to CRH‑producing cells, suggesting a direct link.
Modi. Meera E ME; Inoue. Kiyoshi K; Barrett. Catherine E CE; Kittelberger. Kara A KA; Smith. Daniel...
In a study on prairie voles, giving the peptide Melanotan II (MTII) or a similar MC4R drug helped the animals form lasting pair bonds, and this effect depended on oxytocin. Blocking oxytocin stopped the benefit, and MTII also boosted oxytocin activity in the brain. The researchers think MC4R activation could someday be used to improve social function in people with conditions like autism or schizophrenia.
Surendran. N N; Ugwu. S O SO; Sterling. E J EJ; Blanchard. J J
Scientists created a lab test that can accurately measure the amount of Melanotan‑1 in cell culture fluid and human blood using HPLC, showing it works well across a range of concentrations and is reliable over multiple runs.
Giuliani. Daniela D; Galantucci. Maria M; Neri. Laura L; Canalini. Fabrizio F; Calevro. Anita A; Bit...
In a mouse model of moderate Alzheimer's disease, giving a tiny daily dose of the melanocortin peptide NDP‑α‑MSH (a synthetic version of melanotan‑I) lowered brain amyloid buildup, protected neurons, and improved memory. The benefits disappeared when the MC4 receptor was blocked, showing the peptide works through that pathway.
Veiksina. Santa S; Kopanchuk. Sergei S; Rinken. Ago A
The study shows a new lab test that watches how melanotan‑I‑like peptides stick to the MC4R receptor in real time. Using a brighter, more stable dye (Cy3B) gave clearer results than an older dye (TAMRA). Both peptide versions bound tightly, but they didn’t reach a steady state even after three hours, meaning the interaction is slow.
Do. Ernest U EU; Jo. Eun Bae EB; Choi. Gyu G; Piao. Long Zhu LZ; Shin. Jaekyoon J; Seo. Min-Duk MD;...
Scientists created a test to see how well different peptides stick to the human MC4R protein and found that several short frog‑derived peptides bind strongly and even activate the receptor, acting like full agonists. This shows MC4R can interact with a broader range of peptide shapes than previously thought, but the work is still early‑stage and done in test‑tube and cell‑culture systems.
In a lab cell line (COS-7), the synthetic peptide melanotan‑I (NDP‑alpha‑MSH) only triggers about half the signaling response of natural hormones and makes the receptors become unresponsive faster than the natural versions. This shows that melanotan‑I is a partial activator and that its effects may wear off quickly with repeated use, at least in this cell model.
Yang. Yingkui Y; Chen. Min M; Loux. Tara J TJ; Georgeson. Keith E KE; Harmon. Carroll M CM
The study shows that the tail end of the MC4R receptor (the C‑terminus) is essential for melanotan‑I (NDP‑MSH) to stick to the receptor and trigger its signal, while a different internal loop mainly helps the signal after binding. Cutting off parts of the tail stops the peptide from working, and even smaller cuts weaken its effect.
Gatti. Stefano S; Lonati. Caterina C; Acerbi. Francesco F; Sordi. Andrea A; Leonardi. Patrizia P; Ca...
In rats, a synthetic version of the hormone alpha‑MSH called NDP‑MSH helped protect brain blood vessels after a simulated bleed in the space around the brain. The peptide reduced harmful gene activity, lowered stress‑related protein signals, and lessened the narrowing of arteries that usually follows such bleeding.
Cerdá-Reverter. José Miguel JM; Schiöth. Helgi Birgir HB; Peter. Richard Ector RE
Researchers found that a peptide similar to the skin‑tanning drug melanotan‑I can shrink appetite when directly injected into the brain of goldfish, showing that the appetite‑controlling system using melanocortin signals is ancient and works across species.
Koegler. F H FH; Grove. K L KL; Schiffmacher. A A; Smith. M S MS; Cameron. J L JL
In rhesus monkeys, a drug that mimics the natural hormone alpha‑MSH (NDP‑MSH) lowered how much they ate when given directly into the brain, while blocking that hormone’s action made them eat more. Skipping a meal or fasting also lowered the brain’s production of the hormone’s precursor, showing the system’s role in controlling hunger. This shows the brain’s melanocortin pathway can quickly change food intake in primates.
The study shows that in goldfish, activating the brain’s MC4R receptor with the peptide MTII reduces food intake, while blocking it with HS024 increases eating, suggesting the melanocortin system normally suppresses appetite.
Kim. M S MS; Small. C J CJ; Stanley. S A SA; Morgan. D G DG; Seal. L J LJ; Kong. W M WM; Edwards. C...
The study shows that activating the brain's melanocortin system (like with an alpha‑MSH mimic) can boost thyroid‑stimulating hormone and thyroid hormone levels in rats, while blocking this system with AgRP does the opposite. This links the melanocortin pathway to the thyroid axis, especially during fasting.
Kim. M S MS; Rossi. M M; Abusnana. S S; Sunter. D D; Morgan. D G DG; Small. C J CJ; Edwards. C M CM;...
This rat study shows that activating the MC4R receptor in certain brain areas (especially the PVN, DMN, and MPO) cuts food intake, while blocking it makes rats eat a lot more. The effects were seen when the compounds were injected directly into the brain, not when taken orally or by injection elsewhere. So while it backs up the idea that MC4R‑activating peptides like melanotan‑I could curb appetite, the work doesn’t give a practical dosing guide for humans.
Frändberg. P A PA; Doufexis. M M; Kapas. S S; Chhajlani. V V
This study shows that specific cysteine parts of the skin‑color receptor (MC1R) are crucial for how it binds and reacts to hormone‑like peptides such as alpha‑MSH (the natural version) and synthetic versions like NDP‑MSH. Changing one cysteine (C78) makes the synthetic peptide stop working as an activator and instead block the receptor. While the work is very detailed and done in cells, it hints that natural genetic differences in MC1R could change how people respond to melanotan‑I and similar compounds.
In rats, injecting the alpha‑melanocyte‑stimulating hormone analog NDP‑MSH directly into the brain cuts food intake, even when the animals are hungry or when another appetite‑stimulating peptide (NPY) is given. It doesn’t change water drinking and triggers activity in several brain areas linked to feeding, but we still don’t know exactly where it works.
Yang. Y K YK; Fong. T M TM; Dickinson. C J CJ; Mao. C C; Li. J Y JY; Tota. M R MR; Mosley. R R; Van...
Scientists changed specific parts of the human MC4R protein to see which spots are needed for a peptide like melanotan‑I to stick and work. They found a few key amino acids (especially D122, D126, F261, H264) that are crucial for strong binding and activation.
Catania. Anna A; Lonati. Caterina C; Sordi. Andrea A; Leonardi. Patrizia P; Carlin. Andrea A; Gatti....
In rats, a single IV dose of the melanotan‑I analogue NDP‑MSH triggered heart changes that look a lot like the protective effect you get from brief, repeated bouts of low‑oxygen (ischemic pre‑conditioning). The drug boosted certain inflammation‑related signals (IL‑6, STAT3, SOCS3) and a protein called Nur77, which together may help the heart survive damage when blood flow returns after a blockage.
Zheng. T T; Villalobos. C C; Nusser. K D KD; Gettys. T W TW; Faught. W J WJ; Castaño. J P JP; F...
The study shows that the hormone alpha‑MSH (the natural version of melanotan‑I) sticks to a specific type of pituitary cell that makes prolactin, and it triggers a calcium signal inside those cells. It doesn’t share the same binding spot as dopamine. This was seen in lactating rats, not humans.