Research Brief
Melanotan 2: Safety Profile & Research Summary
Resumo da Pesquisa Pre-clinica
Key Preclinical Studies
| Estudo | Modelo | Principais Achados | Ref |
|---|---|---|---|
| Côté et al. (2017) | F344BN rats — ICV 0.04–1 µg/day × 40d | Fat pads -35% to -55% (p<0.01/0.001); iBAT thermogenesis 3-fold ↑; food intake returned to normal by day 5 — perda de peso via ↑ energy expenditure | [6] |
| Vemulapalli et al. (2001) | NZW rabbits — 66–133 µg/kg IV | Cavernosal pressure 3.2-fold ↑ (p<0.05); abolished by MC3/4 antagonist SHU 9119, pudendal nerve transection, or L-NAME → centrally-mediated NO release | [5] |
| Minakova et al. (2019) | MIA autism-model mice — ICV 2.5 µg/day × 7d | Sociability index 3.1 → 26.3 (p<0.0001); anxiety unchanged; rescued social deficits to control levels | [11] |
| Ford et al. (2024) | Prairie voles (WT vs Oxtr-KO) — IP/ICV | Social context → NAcc Fos ↑ (p<0.01) in WT but NOT Oxtr-KO; non-social → PVN ativacao apenas → oxytocin-dependent social learning mechanism | [7] |
| Jain et al. (2018) | C57BL/6J mice — 10 mg/kg IP | Plasma histamine 4-fold ↑ (p<0.0001); profound hypothermia abolished in mast cell-deficient mice; SC route ↓ histamine 63% | [8] |
| Eliason et al. (2022) | C57BL/6J mice — NAcc microinjection | All doses ↓ food intake at 1,2,4,6h (p<0.05); diminuiu lever-pressing motivation; no aversive state or metabolic rate change | [10] |
| Wu et al. (2020) | B16-F10 melanoma mice — topical | Dramatically slowed tumor growth; ↑PTEN, ↓COX-2/PGE2, induziu cell death; inibiu migration/invasion | [14] |
Human Clinical Data
| Estudo | Population | Key Results | Ref |
|---|---|---|---|
| Dorr et al. (1996) — Phase I | n=3 healthy males; 0.01–0.025 mg/kg SC | Visible tanning in 2/3 subjects; spontaneous erections 1–5h post-dose; mild nausea; recommended Phase I dose: 0.025 mg/kg | [1] |
| Wessells et al. (1998) — Psychogenic ED | n=10 men; 0.025 mg/kg SC, duplo-cego crossover | 80% response rate; tip rigidity >80% for 38 min vs 3 min placebo (p=0.0045) | [3] |
| Wessells et al. (2000) — Organic ED | n=10 men; 0.025 mg/kg SC, duplo-cego crossover | 63% erection rate (12/19 injections vs 1/21 placebo); tip rigidity >80% for 45.3 min vs 1.9 min (p=0.047); aprimorou sexual desire | [9] |
Safety Concerns — Case Reports (Unregulou Use)
| Event | Details | Ref |
|---|---|---|
| Priapism | 22-hour painful erection (unknown dose); 60-year-old required surgical shunting after 10 mg injection | [15] |
| Rhabdomyolysis | 39-year-old male: 6 mg SC → CPK 17,773 IU/L; tachycardia, hipertensao, agitation, renal dysfunction | [16] |
| Renal Infarction | 45-year-old male: 50% right kidney infarction after 10 mg injections; likely sympathomimetic vasoconstricao | [17] |
| Melanoma/Nevi Changes | 16-year-old female (FAMMM): darkened/enlarged nevi + dysplastic nevus after 2 months (0.5 mg/day); melanoma in situ reports | [18] |
| Common Side Effects | Nausea (dose-dependente), facial flushing, fatigue, yawning/stretching, diminuiu appetite, darkened moles | [1] |
Pharmacokinetics & Dosing Summary
| Parametro | Valor |
|---|---|
| Human Half-Life | ~1–2 hours (aprimorou vs α-MSH by cyclic structure) |
| BBB Penetration | Yes (diferentemente de Melanotan I) |
| Active Metabolite | Bremelanotide (PT-141) — deaminated, lacks C-terminal amide |
| ED Research Dose | 0.025 mg/kg SC (Phase I optimal for erection with manageable efeitos colaterais) |
| Contraindications | Cardiovascular disease; personal/family melanoma history; PDE5 inhibitor combination (priapism risk) |
Os produtos oferecidos neste site são fornecidos apenas para estudos in vitro. Estudos in vitro (do latim: em vidro) são realizados fora do corpo. Estes produtos não são medicamentos ou fármacos e não foram aprovados pelo FDA dos EUA para prevenir, tratar ou curar qualquer condição médica, enfermidade ou doença. A introdução corporal de qualquer tipo em humanos ou animais é estritamente proibida por lei.
Apenas para Pesquisa Laboratorial. Não se destina ao uso humano, uso médico, uso diagnóstico ou uso veterinário.
TODOS OS ARTIGOS E INFORMAÇÕES SOBRE PRODUTOS FORNECIDOS NESTE SITE SÃO APENAS PARA FINS INFORMATIVOS E EDUCACIONAIS.
Referencias
- Dorr RT, Lines R, Levine N, et al. Evaluation of melanotan-II, a superpotent cyclic melanotropic peptide in a pilot phase-I clinical study. Life Sciences. 1996;58(20):1777-1784.
- Hadley ME, Dorr RT. Melanocortin peptide therapeutics: Historical milestones, clinical studies and commercialization. Peptides. 2006;27(4):921-930.
- Wessells H, Fuciarelli K, Hansen J, et al. Synthetic melanotropic peptide inicia erections in men with psychogenic erectile dysfunction: Double-blind, placebo controlled crossover study. The Journal of Urology. 1998;160(2):389-393.
- FDA Warning Letters regarding unauthorized marketing of Melanotan products.
- Vemulapalli R, Kurowski S, Salisbury B, et al. Activation of central melanocortin receptors by MT-II aumenta cavernosal pressure in rabbits pelo(a) neuronal release of NO. British Journal of Pharmacology. 2001;134(8):1705-1710.
- Côté I, et al. Activation do(a) central melanocortin system chronically reduz body mass sem the necessity of longo prazo caloric restriction. Canadian Journal of Physiology and Pharmacology. 2017.
- Ford CL, McDonough AA, Horie K, Young LJ. Melanocortin agonism in a social context ativa seletivamente nucleus accumbens in an oxytocin-dependent manner. Neuropharmacology. 2024;247:109848.
- Jain S, Panyutin A, Liu N, et al. Melanotan II causes hypothermia in mice by ativacao of mast cells and estimulacao of histamine 1 receptors. American Journal of Physiology-Endocrinology and Metabolism. 2018;315(3):E357-E366.
- Wessells H, Levine N, Hadley ME, Dorr RT, Hruby VJ. Effect of an alpha-melanocyte stimulating hormone analog on penile erection and sexual desire in men with organic erectile dysfunction. Urology. 2000;56(4):641-646.
- Eliason NL, Martin L, Low MJ, Sharpe AL. Melanocortin agonista do receptor melanotan-II microinjected no(a) nucleus accumbens diminui appetitive and consumptive responding for food. Neuropeptides. 2022;96:102289.
- Minakova E, Lang J, Medel-Matus JS, et al. Melanotan-II reverses autistic features in a maternal immune ativacao modelo de camundongo of autism. PLoS ONE. 2019;14(1):e0210389.
- Ter Laak MP, et al. Melanotan II promove periferico(a) regeneracao nervosa in a rat sciatic nerve crush model. 2003.
- Evans-Brown M, Dawson RT, Chandler MD, McVeigh J. Use of melanotan I and II no(a) general population. BMJ. 2009;338:b566.
- Wu JC, Tsai HE, Hsiao YH, et al. Topical MTII Therapy Suppresses Melanoma Through PTEN Upregulacao and Cyclooxygenase II Inhibition. International Journal of Molecular Sciences. 2020;21(2):681.
- Dreyer BA, Amer T, Fraser M. Melanotan-induziu priapism: a hard-earned tan. BMJ Case Reports. 2019;12(2):e227644.
- Nelson ME, Bryant SM, Aks SE. Melanotan II injection resultando em sistemico(a) toxicity and rhabdomyolysis. Clinical Toxicology. 2012;50(10):1169-1173.
- Peters B, Hadimeri H, Wahlberg R, Afghahi H. Melanotan II: a possible cause of renal infarction. CEN Case Reports. 2020;9(2):159-161.
- Sivyer GW. Dermatological changes with melanotan II use in a FAMMM patient. Dermatology Practical & Conceptual. 2012.
- Ryakhovsky VV, Khachiyan GA, Kosovova NF, et al. The primeiro(a) preparative solution phase synthesis of melanotan II. Beilstein Journal of Organic Chemistry. 2008;4:39.
- Hjuler KF, Lorentzen HF. Melanoma associado(a) com the use of melanotan-II. Dermatology. 2014;228(1):34-36.
- Giuliano F, Clement P, Droupy S, et al. Melanotan-II: Investigation do(a) inducer and facilitator effects on penile erection in anaesthetized rat. Neuroscience. 2006;138(1):293-301.
- Li G, Zhang Y, Wilsey JT, Scarpace PJ. Unabated anorexic and aprimorou thermogenic responses to melanotan II in diet-induziu ratos obesos. Journal of Endocrinology. 2004;182(1):123-132.
- King SH, et al. Melanocortin Receptors, Melanotropic Peptides and Penile Erection. Current Topics in Medicinal Chemistry. 2007;7(11):1111-1119.
- Wessells H, Levine N, Hadley ME, Dorr RT, Hruby VJ. Melanocortin agonista do receptors, penile erection, and sexual motivation: human studies with Melanotan II. International Journal of Impotence Research. 2000;12(Suppl 4):S74-S79.
Perguntas de Pesquisa Relacionadas
APENAS PARA USO EM PESQUISA
Este conteudo e fornecido apenas para fins educacionais e informativos. Os produtos sao fornecidos apenas para estudos in vitro e nao sao medicamentos, drogas ou suplementos. Nao aprovado pela FDA para prevenir, tratar ou curar qualquer condicao.
