Stratum corneum water and polar components (NMF)

The stratum corneum (SC) water and polar components, primarily represented by the Natural Moisturizing Factor (NMF), are critical for maintaining the hydration, elasticity, and barrier integrity of the skin's outermost layer (Source: StatPearls, Physiology, Stratum Corneum). The NMF consists of a complex mixture of low-molecular-weight, highly hygroscopic substances such as amino acids, pyrrolidone carboxylic acid (PCA), urea, and lactates, which are largely generated through the proteolytic degradation of the protein filaggrin (Source: Journal of Investigative Dermatology, Filaggrin in the pathway to atopic dermatitis). These polar components function by capturing and holding water within the corneocytes, which is essential for the activity of enzymes involved in desquamation and for preventing the skin from becoming brittle (Source: PubMed, The role of water in the stratum corneum). In pathological states like atopic dermatitis or xerosis, a reduction in these components leads to impaired barrier function, increased transepidermal water loss (TEWL), and inflammation (Source: NIH, Skin Barrier Function and the Natural Moisturizing Factor). Therapeutic strategies target these components using humectants like glycerin, urea, and hyaluronic acid, which topically supplement the SC's ability to retain moisture and restore its physiological properties (Source: Clinical, Cosmetic and Investigational Dermatology, Moisturizers: The Slippery Road).

Other names

Natural Moisturizing FactorCorneocyte hydrationStratum corneum hydrationSkin polar componentsHydrophilic components of the stratum corneum

Humectancy and osmotic hydration of the stratum corneum through the attraction and binding of water molecules.