This data is for laboratory research purposes only. Not for human or animal consumption.
What is Melanotan I (Bremelanotide)?
Melanotan I, also known as bremelanotide, is a melanocortin receptor agonist peptide that selectively activates melanocortin receptors 3 and 4 (MC3R/MC4R). In glioblastoma cell line models, this peptide demonstrates cytotoxic activity through survivin pathway inhibition, with potential synergistic effects when combined with standard chemotherapeutic agents.
Mechanism of Action
Bremelanotide exerts its anti-glioblastoma effects by binding to and activating melanocortin receptors 3 and 4 on tumor cell membranes. This activation triggers a downstream signaling cascade that suppresses survivin (an anti-apoptotic protein from the inhibitor of apoptosis family), thereby removing a critical survival signal and sensitizing glioblastoma cells to programmed cell death. The mechanism is receptor-dependent, as MC3R/MC4R antagonists completely block the observed cytotoxic effects, confirming target specificity.
Observed Laboratory Results
- Survivin suppression: Bremelanotide reduced survivin expression in human glioblastoma cell lines at concentrations non-toxic to normal human cells, with forced survivin overexpression completely preventing bremelanotide-induced cell death.
- Chemotherapy sensitization: Bremelanotide promoted cell death induced by temozolomide and osimertinib in glioblastoma models, suggesting synergistic potential in combination therapeutic approaches.
- Receptor specificity: All observed cytotoxic effects were abolished in the presence of melanocortin receptor 3/4 antagonists, establishing MC3R/MC4R as the molecular targets responsible for anti-tumor activity.