Stratum corneum model membranes : molecular organization in relation to skin barrier function

Groen, D. (2011)

Doctoral Thesis

The stratum corneum (SC), the thin uppermost layer of the skin, consists of dead flattened skin cells (corneocytes) embedded in a lipid matrix. The lipid matrix is considered to play a crucial role in the skin barrier function. It consists of ceramides (CER), cholesterol (CHOL) and free fatty acids (FFA) forming crystalline lipid lamellae. From studies with native SC and SC lipid models much information has been gained on the phase behavior of the SC lipid matrix. However, little is known about the correlation between SC lipid organization and the permeability of the SC. This is difficult to investigate using native SC, due to its complex structure. Therefore SC lipids were casted on a porous membrane, resulting in a lipid organization and lamellar orientation similar to that in SC. This lipid membrane is referred to as the stratum corneum substitute (SCS). The SCS can be used to perform diffusion studies. Therefore, when modifying the lipid composition and thus the lipid organization in the SCS, it is possible to study the relationship between lipid organization and permeability. The main objectives of this thesis are 1) to investigate the influence of lipid organization on the barrier function in the SCS and 2) to obtain insights in the molecular organization within the unit cell of the lamellar phases in SC.

• X-ray diffraction
• Stratum corneum
• Skin
• Permeability model
• Neutron diffraction
• Lipid model
• FTIR
• Ceramides

• All authors: Groen, D.
• Supervisor: Bouwstra, J.A.
• Qualification: Doctor (dr.)
• Awarding Institution: Faculty of Science, Leiden University
• Date: 2011-10-25