Sir, We read with interest the letter from Thestrup-Pedersen & Søndergaard (1) reporting the augmentation of len-tiges and naevi in a young male patient who had been self-injecting with " melanotan ". As in a case we initially reported (2), a clinically suspicious naevus was excised, with histology revealing a benign naevus, with no evidence of malignant transformation. The patient was also not...

Alpha melanocyte stimulating hormone (α-MSH) is an agonist at the melanocortin 3 (MC3-R) and melanocortin 4 (MC4-R) receptors. α-MSH stimulates corticosterone release from rat and human adrenal cells. Patients with Cushing’s syndrome have elevated levels of serum α-MSH. Agouti related protein (AgRP) is an endogenous antagonist at the MC3-R and MC4-R and is expressed in the rat adrenal cortex. A...

OBJECTIVE Puberty is a key developmental phenomenon highly sensitive to metabolic modulation. Worrying trends of changes in the timing of puberty have been reported in humans. These might be linked to the escalating prevalence of childhood obesity and could have deleterious impacts on later (cardio-metabolic) health, but their underlying mechanisms remain unsolved. The neuropeptide α-MSH, made ...

The melanocortin 1 receptor (MC1R), a G(s) protein-coupled receptor, has an important role in human pigmentation. We investigated the regulation of expression and activity of the MC1R in primary human melanocyte cultures. Human β-defensin 3 (HBD3) acted as an antagonist for MC1R, inhibiting the α-melanocortin (α-melanocyte-stimulating hormone (α-MSH))-induced increase in the activities of adeny...

Abstract Pro-opiomelanocortin (POMC) neurons in the hypothalamus play a role both control of metabolic state and sexual behavior. Along with fast neurotransmitters glutamate and/or GABA, POMC secrete cocaine- amphetamine-regulated transcript (CART) products gene, including β-endorphin α-melanocortin stimulating hormone (α-MSH). Published data from our lab demonstrate lack interest male mice whe...

BACKGROUND Exposure to ultraviolet (UV) radiation causes various forms of acute and chronic skin damage, including immunosuppression, inflammation, premature aging and photodamage. Furthermore, it induces the generation of reactive oxygen species, produces proinflammatory cytokines and melanocyte-stimulating hormone (MSH) and increases tyrosinase activity. The aim of this study was to evaluate ...

The melanocortin 1 receptor (MC1R) is a highly polymorphic G protein-coupled receptor, which is known to modulate pigmentation and inflammation. In the current study, we investigated the pharmacological effects of select single-nucleotide polymorphisms (SNPs) (V60L, R163Q, and F196L). After transient expression of MC1Rs in human embryonic kidney 293 cells, basal and ligand-induced cAMP signalin...

Selectively bred diet-induced obese (DIO) rats become obese on a high-fat diet and are leptin resistant before becoming obese. Compared with diet-resistant (DR) neonates, DIO neonates have impaired leptin-dependent arcuate (ARC) neuropeptide Y/agouti-related peptide (NPY/AgRP) and α-melanocyte-stimulating hormone (α-MSH; from proopiomelanocortin (POMC) neurons) axon outgrowth to the paraventric...

The evolution of the melanocortin receptors (MCRs) is linked to the evolution of adrenocorticotrophic hormone (ACTH), the melanocyte-stimulating hormones (MSHs), and their common precursor pro-opiomelanocortin (POMC). The origin of the MCRs and POMC appears to be grounded in the early radiation of the ancestral protochordates. During the genome duplications that have occurred during the evoluti...