Water is essential for the normal functioning of the skin, especially for the Stratum Corneum (SC), which is the selectively permeable outer layer of the skin (1). The SC provides a highly efficient barrier against water loss (2). Everyday conditions like cold, wind, air conditioning, the use of soap, and other factors are the main cause of hydration disruption in the SC resulting in noticeable scaling, itching, and damaged skin.
The skin protects us against the environment and regulates water exchange. Internal factors, such as the Natural Moisturising Factor, certain proteins involved in water transport and the effects of the natural aging process affect water content in the SC. There is a great and continuous water exchange among the SC, the underlying epidermal living cells and the atmosphere, which depends on SC adequate conditions and integrity.
Glycosaminoglycans (GAGs) are macromolecules present in the Extracellular Matrix (ECM), which are composed of repeated disaccharide units, forming long, linear and negatively charged heterogeneous polysaccharides. Hyaluronic Acid (HA) is a GAG found in the skin as a main constituent of the ECM. The hydrophilic chain ...