The human skin barrier is organized as stacked bilayers of fully extended ceramides with cholesterol molecules associated with the ceramide sphingoid moiety.

I. IWAI; H.HAN; L. DEN HOLLANDER; S. SVENSSON; L.G. OFVERSTEDT; J.ANWAR; J. BREWER; M. BLOKSGAARD; L. LALOEUF; D. NOSEK; S. MASICH; LUIS A. BAGATOLLI; U. SKOGLUND; L. NORLÉN

JOURNAL OF INVESTIGATIVE DERMATOLOGY

NATURE PUBLISHING GROUP

Lugar: Londres; Año: 2012 vol. 132 p. 2215 - 2215

0022-202X

he skin barrier is fundamental to terrestrial life and its evolution; it upholds homeostasis and protects against the environment. Skin barrier capacity is controlled by lipids that fill the extracellular space of the skin´s surface layer--the stratum corneum. Here we report on the determination of the molecular organization of the skin´s lipid matrix in situ, in its near-native state, using a methodological approach combining very high magnification cryo-electron microscopy (EM) of vitreous skin section defocus series, molecular modeling, and EM simulation. The lipids are organized in an arrangement not previously described in a biological system-stacked bilayers of fully extended ceramides (CERs) with cholesterol molecules associated with the CER sphingoid moiety. This arrangement rationalizes the skin´s low permeability toward water and toward hydrophilic and lipophilic substances, as well as the skin barrier´s robustness toward hydration and dehydration, environmental temperature