title: Thermotropic phase behavior of in vivo extracted human stratum corneum lipids.
abstract: The thermotropic phase behavior of lipids extracted either in vivo from inner forearm (SCLE) or plantar callus (PC) was investigated by differential scanning calorimetry and small angle X-ray diffraction. PC composition was chromatographically modified (MPC) by eliminating the more polar lipids in order to evaluate their role. Analysis of composition confirms the potential use of PC as a source of stratum corneum lipids. MPC and SCLE exhibit similar differential scanning calorimetry (DSC) profiles with a main transition around 50 degrees C attributed to the solid-to-liquid phase transition of the ceramides. The absence of a transition around 50 degrees C for PC suggests the possible perturbation of ceramide packing by the significantly high proportion of phospholipids. X-ray data suggest a high miscibility of sebum components in stratum corneum lipids with possible modification of chain packing. The MPC patterns show a lipid phase separation which underscores the role of polar lipids in cholesterol/free fatty acids/sterol esters/ceramides structural cohesion.
authors.affiliation: Parfums Christian Dior, St. Jean de Braye, France.
authors.forename: F
authors.initials: F
authors.lastname: Bonté
authors.forename: P
authors.initials: P
authors.lastname: Pinguet
authors.forename: A
authors.initials: A
authors.lastname: Saunois
authors.forename: A
authors.initials: A
authors.lastname: Meybeck
authors.forename: S
authors.initials: S
authors.lastname: Beugin
authors.forename: M
authors.initials: M
authors.lastname: Ollivon
authors.forename: S
authors.initials: S
authors.lastname: Lesieur
mesh_terms: D000328:Adult; D002145:Callosities; D002152:Calorimetry, Differential Scanning; D002518:Ceramides / Q000032:analysis; D002784:Cholesterol / Q000032:analysis; D002845:Chromatography / Q000379:methods; D002855:Chromatography, Thin Layer / Q000379:methods; D004817:Epidermis / Q000737:chemistry*; D005542:Forearm / Q000033:anatomy & histology; D006801:Humans; D008055:Lipids / Q000032:analysis* / Q000737:chemistry*; D010743:Phospholipids; D014961:X-Ray Diffraction
chemical_list: D002518:Ceramides; D008055:Lipids; D010743:Phospholipids; D002784:Cholesterol