Publication: Cannabinoid receptors 1 and 2 oppositely regulate epidermal permeability barrier status and differentiation.
Roelandt T, Heughebaert C, Bredif S, Giddelo C, Baudouin C, Msika P, Roseeuw D, Uchida Y, Elias PM, Hachem JP. Exp Dermatol. 2012 Sep;21(9):688-93.
Synopsis and Significance: Both the outer part of skin, the epidermis, and the brain derive from the epithelial layer that covers the outside of the embryo during early fetal life. Likely because of this common origin, the epidermis and brain share virtually the same repertoire of ‘emotional’ neurotransmitters. It has been largely assumed that these chemicals and their receptors in the skin send messages on to the brain, but our recent research suggests instead that they function as a type of ‘brain within the skin’. In this paper we show in genetically-modified mice, that a family of ligands, called cannabinoids, after binding to one of their their specific receptors, regulate a host of critical metabolic responses that affect function of the permeability barrier of the skin. One of the receptors, when activated, improves barrier function, while the other impairs function. What triggers this regulatory system remains to be determined.