title: Stratum corneum drying drives vertical compression and lipid organization and improves barrier function in vitro.
abstract: The stratum corneum dehydrates after exogenous hydration due to skincare or bathing. In this study, sheets of stratum corneum were isolated from reconstructed human epidermis and the barrier function and structure of these sheets were assessed during drying with the aim of improving our understanding of skincare. Water diffusion through the sheets of stratum corneum decreased with drying, accompanied by decreased thickness and increased visible light transmission through the sheets. Electron paramagnetic resonance revealed that the order parameter values of stratum corneum lipids increased with drying. X-ray diffraction analysis revealed increases in the diffraction intensity of lamellar structures, with an 11-12 nm periodicity and spacing of 0.42 nm for lattice structures with drying. These results suggest that the drying process improves the barrier function of the stratum corneum by organizing the intercellular lipids in a vertically compressed arrangement.
authors.affiliation: Shiseido Research Center, 2-2-1 Hayabuchi, Yokohama 224-8558, Japan. ichiro.iwai@to.shiseido.co.jp
authors.forename: Ichiro
authors.initials: I
authors.lastname: Iwai
authors.forename: Naomi
authors.initials: N
authors.lastname: Kunizawa
authors.forename: Eiichiro
authors.initials: E
authors.lastname: Yagi
authors.forename: Tetsuji
authors.initials: T
authors.lastname: Hirao
authors.forename: Ichiro
authors.initials: I
authors.lastname: Hatta
mesh_terms: D001494:Baths / Q000009:adverse effects; D001834:Body Water / Q000378:metabolism*; D003890:Desiccation; D004058:Diffusion; D004578:Electron Spin Resonance Spectroscopy; D004817:Epidermis / Q000378:metabolism* / Q000473:pathology; D006801:Humans; D050356:Lipid Metabolism; D018613:Microscopy, Confocal; D010539:Permeability; D017592:Skin Care / Q000009:adverse effects; D013997:Time Factors; D046509:Tissue Culture Techniques; D014870:Water Loss, Insensible; D014961:X-Ray Diffraction