What exactly is the skin barrier? We spend all day in our offices treating the skin barrier, but very few of us can discuss the skin barrier in the explicit detail presented in this text entitled Cosmetic Lipids and the Skin Barrier, edited by Thomas Förster. This book, largely written by European experts, presents the current thinking on the subject. It introduces the chemistry and structure of skin lipids, beginning with an elegant distinction between ceramides, cholesterol, and water that occupy the intercellular spaces, and sebum that contains no ceramides, little cholesterol, and a substantial proportion of squalene that resides on the skin surface. This leads to a discussion on the development of artificial ceramides and lipid liposomes that represent the up-and-coming ingredients in skin moisturizers. Many of these lipid analogues are designed and studied by computer modeling of molecular dynamics. If success is achieved in the computer model, in vitro models are then used to further examine their utility. These in vitro models include monolayer keratinocyte and fibroblast cultures, as well as tissue-engineered epidermis. The next step is clinical testing to determine if the newly synthesized lipid has value in vivo.
Draelos ZD. Cosmetic Lipids and the Skin Barrier (Cosmetic Science and Technology Series, Vol 24). Arch Dermatol. 2003;139(4):549-000. doi:10.1001/archderm.139.4.549