Potential therapeutic effects of odorants through their ectopic receptors in pigmented cells

Several olfactory receptors (ORs) have been characterized outside of the olfactory neuro-epithelium in neuronal and non-neuronal tissues, where they were implicated in the recognition of diverse chemical signals. ORs have been found expressed and regulating melanogenesis in skin melanocytes. Besides, ORs expression have been found in the human brain nigrostriatal dopaminergic neurons, where production of melanin occurs as neuromelanin and may change with age, as well as ORs expression is down-regulated in Parkinson’s disease. Therefore, we propose several odorants as new functional ligands to ORs expressed in non-olfactory pigmented cells, as dopaminergic neurons and melanocytes, where, by acting on cAMP-induced melanin production, they could help to counteract both melanogenic and neurodegenerative dysfunctions, including melanoma, Parkinson’s and Alzheimer’s diseases.