Cosmetic use of at least one ligand of the neuropeptide Y (NPY) receptor (I) comprising agonist and antagonist of NPY, in a composition containing a medium, as an agent for the maintenance and/or restoration of homeostasis of the epidermis and/or mucous membranes, is claimed. ACTIVITY : Dermatological; Antiseborrheic; Antipsoriatic; Keratolytic; Vasotropic; Vasodilator; Metabolic. MECHANISM OF ACTION : Neuropeptide Y (NPY) receptor modulator.