title: Effect of ceramide acyl chain length on skin permeability and thermotropic phase behavior of model stratum corneum lipid membranes.
abstract: Stratum corneum ceramides play an essential role in the barrier properties of skin. However, their structure-activity relationships are poorly understood. We investigated the effects of acyl chain length in the non-hydroxy acyl sphingosine type (NS) ceramides on the skin permeability and their thermotropic phase behavior. Neither the long- to medium-chain ceramides (8-24 C) nor free sphingosine produced any changes of the skin barrier function. In contrast, the short-chain ceramides decreased skin electrical impedance and increased skin permeability for two marker drugs, theophylline and indomethacin, with maxima in the 4-6C acyl ceramides. The thermotropic phase behavior of pure ceramides and model stratum corneum lipid membranes composed of ceramide/lignoceric acid/cholesterol/cholesterol sulfate was studied by differential scanning calorimetry and infrared spectroscopy. Differences in thermotropic phase behavior of these lipids were found: those ceramides that had the greatest impact on the skin barrier properties displayed the lowest phase transitions and formed the least dense model stratum corneum lipid membranes at 32°C. In conclusion, the long hydrophobic chains in the NS-type ceramides are essential for maintaining the skin barrier function. However, this ability is not shared by their short-chain counterparts despite their having the same polar head structure and hydrogen bonding ability.
authors.affiliation: Department of Inorganic and Organic Chemistry, Charles University in Prague, Hradec Králové, Czech Republic.
authors.forename: Barbora
authors.initials: B
authors.lastname: Janůšová
authors.forename: Jarmila
authors.initials: J
authors.lastname: Zbytovská
authors.forename: Petr
authors.initials: P
authors.lastname: Lorenc
authors.forename: Helena
authors.initials: H
authors.lastname: Vavrysová
authors.forename: Karel
authors.initials: K
authors.lastname: Palát
authors.forename: Alexandr
authors.initials: A
authors.lastname: Hrabálek
authors.forename: Kateřina
authors.initials: K
authors.lastname: Vávrová
mesh_terms: D000894:Anti-Inflammatory Agents, Non-Steroidal / Q000494:pharmacology; D002518:Ceramides / Q000737:chemistry* / Q000378:metabolism; D006358:Hot Temperature; D006801:Humans; D007213:Indomethacin / Q000494:pharmacology; D008956:Models, Chemical; D010539:Permeability / Q000187:drug effects; D010726:Phosphodiesterase Inhibitors / Q000494:pharmacology; D012867:Skin / Q000737:chemistry* / Q000378:metabolism; D013110:Sphingosine / Q000737:chemistry / Q000378:metabolism; D013806:Theophylline / Q000494:pharmacology
chemical_list: D000894:Anti-Inflammatory Agents, Non-Steroidal; D002518:Ceramides; D010726:Phosphodiesterase Inhibitors; D013806:Theophylline; D013110:Sphingosine; D007213:Indomethacin