Octyl glucoside as a tool to induce structural modifications in the stratum corneum

The combined action of the octyl glucoside (OG) surfactant at concentrations 10 and 20 mM and ultrasonic stimulation was used to induce structural modifications in the pig stratum corneum (SC). The composition of the disaggregated material and the microstructure of the residual tissue after treatment were studied. This combined treatment mainly removed proteins and small amounts of lipids. The disaggregated components formed complexes via hydrophobic interactions and covalent bonds. The presence in the disaggregated fraction of glutamic acid residues covalently linked to ceramides indicated that the OG affected the corneocyte envelopes. The loss of SC cohesion was associated with the disaggregation of the protein tissue components. This fact underlines the important role played by the corneocyte envelopes in the tissue cohesion. Transmission electron microscopy (TEM) showed that the lamellar lipid structure was only slightly affected by the treatment, despite the strong disruption of the protein domains. TEM image analysis also confirmed that the interlamellar spaces of treated SC were similar to those of the native tissue. High resolution low-temperature scanning electron microscopy corroborated these observations. However, this technique detected alterations of the lipid areas attributed to the interaction of the proteins liberated from the corneocytes and the lipids. These results suggest a tissue disaggregation process in layers, which occurred by disruption of SC into corneocytes, disaggregation of the corneocyte envelopes and preservation of the intercellular lamellae structure.