Actives proposed for skin care generally are focused on wrinkle prevention—but another sign of aging is fragile skin. During aging, the epidermis becomes thinner, the cohesion of the epidermal cells diminishes and the epidermis loses its resistance to environmental aggressors. The skin becomes dry and slack and consequently is easily damaged even with the lightest friction or shock.
To enhance epidermal cohesion, Laboratoires Sérobiologiques has developed an antiaging active designed to target two proteins that affect epidermis cohesion: syndecan-1 and type XVII collagen.
In the skin, proteoglycans (PG) and glycosaminoglycans (GAG) are present not only in the extracellular matrix of the dermis, but also in the epidermis. Syndecans represent the major form of PG synthesized by the epidermis with syndecan-1, a small PG with a MW <60,000 da, located in supra-basal layers of the epidermis. Syndecan-1 plays an important role in keratinocyte activation during wound healing. In addition, it has diverse functions including the regulation of cell signaling such as by fibroblast growth factors, participation in cell-to-cell and cell-to-laminin adhesion, and in the organization of cell matrix adhesion. According to Carey, syndecan-1 may link the intracellular cytoskeleton to the interstitial matrix.