Moisture barrier function

The **moisture barrier function** refers to the composite property of the skin’s outermost layers (primarily the stratum corneum) that prevents excessive loss of water from the body and maintains internal hydration. This function is mediated by a combination of structural proteins (such as keratin), natural moisturizing factors (NMFs), lipids (including ceramides, cholesterol, and fatty acids), and cellular arrangements (like corneocytes and tight junctions)[1][2][3][4][7]. Defects in the barrier can result in transepidermal water loss, dry skin, inflammatory skin diseases, and increased vulnerability to allergens and pathogens[3][4][5][7]. Common strategies to support or restore the moisture barrier include using topical moisturizers that contain ceramides, hyaluronic acid, and occlusives, which reinforce or mimic the natural components of the skin barrier[4][7]. Unlike named molecular targets (such as "Interleukin-17A" or "Epidermal growth factor receptor"), "moisture barrier function" is not a defined protein, receptor, or transporter and cannot directly be targeted by drugs; rather, drugs and skincare products act upon the barrier through various mechanisms affecting its constituent components[1][2][4][5][7].

Other names

Skin barrier functionTransepidermal water loss preventionStratum corneum barrierSkin moisture retention mechanism

Not applicable; this term describes a physiological property, not a molecular target with a direct mechanism of action for drug binding. Therapeutic interventions aim to support or restore the barrier's constituent components.