Modulation of Stratum Corneum Lipid Composition and Organization of Human Skin Equivalents by Specific Medium Supplements
Authors
Varsha S. Thakoersing, Jeroen van Smeden, Walter A. Boiten, Gert S. Gooris, Aat A. Mulder, Rob J. Vreeken, Abdoelwaheb El Ghalbzouri, Joke A. Bouwstra
Institution
University of Leiden
Country
Netherlands
Year
2015
Journal
Experimental Dermatology
Abstract
Our in-house human skin equivalents contain all stratum corneum (SC) barrier lipid classes,
but have a reduced level of free fatty acids (FAs), of which a part is mono-unsaturated. These
differences lead to an altered SC lipid organization and thereby a reduced barrier function
compared to human skin. In this study we aimed to improve the SC FA composition and
consequently the SC lipid organization of the Leiden Epidermal Model (LEM) by specific
medium supplements. The standard FA mixture (consisting of palmitic, linoleic and
arachidonic acid) supplemented to the medium was modified, by replacing protonated
palmitic acid with deuterated palmitic acid or addition of deuterated arachidic acid to the
mixture, to determine whether FAs are taken up from the medium and are incorporated into
SC of LEM. Furthermore, supplementation of the total FA mixture or that of palmitic acid
alone was increased four times to examine whether this improves the SC FA composition and
lipid organization of LEM. The results demonstrate that the deuterated FAs are taken up into
LEMs and are subsequently elongated and incorporated in their SC. However, a fourfold
increase in palmitic acid supplementation does not change the SC FA composition or lipid
organization of LEM. Increasing the concentration of the total FA mixture in the medium
resulted in a decreased level of very long chain FAs and an increased level of monounsaturated
FAs, which lead to deteriorated SC lipid properties. These results indicate that SC
lipid properties can be modulated by specific medium supplements.