Overview
- Slominski, A. and Wortsman, J. (2000) Endocr. Rev. 21, 457.
- Yeo, G.S. et al. (2000) QJM 93, 7.
- Ohguchi, K. et al. (2004) J. Biol. Chem. 279, 3408.
- Alomone Labs α-MSH induces melanogenesis in B16 melanoma cells.Cells were incubated with increasing concentrations of α-MSH (#GPM-100). Melanin production was measured after 3 days and plotted against α-MSH concentrations (ED50 = 67 ng/ml, upper graph). Below the graph is a visual representation of melanin production intensity following α-MSH stimulation for three days.
α-MSH is a neuropeptide originally isolated from the pituitary gland1. α-MSH is produced by post-translational processing of a precursor protein, proopiomelanocortin (POMC)2. In most vertebrates but not in mammals, α-MSH is produced in the intermediate lobe of the pituitary gland. The biological activities of α-MSH are mediated through a family of five specific G-protein coupled receptors: MCR1, MCR2, MCR3, MCR4, and MCR5. α-MSH is an evolutionarily highly conserved peptide action that induces pigment dispersion in skin melanocytes of amphibians, reptiles and mammals by stimulating melanin production3,4.
However, in human and other mammals, α-MSH acts in the brain in appetite suppression and sexual arousal. Some cases of extreme obesity have been traced to mutated α-MSH receptor in the brain. Presumably, these people are unable to respond to the appetite-suppressing effect of α-MSH5. α-MSH has significant anti-inflammatory properties, mediated through its binding to MCR16 and includes regulation of expression and secretion of chemokines, downregulation of proinflammatory signal-induced NF-kB activation and adhesion molecule expression, prostaglandin E2 synthesis, as well as induction of interleukin-107.