NV NIACINAMIDE

Niacinamide, also known as nicotinamide, is the active form of vitamin B3, which is water- soluble. It has several biological effects, as it is essentially involved in metabolism, trans- cription processes and DNA synthesis regula- tion. This vitamin is essential in cellular energy supply, acts as a precursor of the coenzymes NADH and NADPH, and is thus involved in more than 200 enzymatic reactions in the body, including ATP3 forma- tion. When topically applied, niacinamide has been shown to be useful in improving cuta- neous homeostasis and barrier function, and acts as a therapeutic adjuvant in the treat- ment of various skin conditions . Niacinamide stimulates the synthesis of collagen and proteins involved in the formation of keratin, filaggrin and involucrin, thus improving the skin's hydration, elasticity and general struc- ture. Furthermore, studies have observed the positive impact of niacinamide on the synthe- sis of ceramides, free fatty acids and choles- terol contained in the intercellular spaces of the stratum corneum.

The intercellular spaces of the stratum corneum contain mainly non-polar lipids represented by free fatty acids, cholesterol and ceramides. Lipids are formed by multi- layer bilamellar structures separated by a hydrophilic phase, which form fundamental barriers for maintaining the stratum corneum hydration. There is a correlation between impaired epidermal barrier function and skin conditions such as rosacea, atopic dermatitis, aging and winter xerosis, which can be obser- ved by an increase in transepidermal water loss and reduced stratum corneum hydration. In addition to the rebalancing of lipid produc- tion, niacinamide has been shown to decrease skin dehydration through a regulatory action on aquaporin 3, which plays a significant role in restoring the skin's barrier function.