Permeation of Nicotinamide Mononucleotide (NMN) in an Artificial Membrane as a Cosmetic Skin Permeability Test Model

Skin aging progresses owing to intrinsic factors, including chronological alterations, and extrinsic factors, including ultraviolet radiation (UV), smoking, and air pollution. One of the mechanisms of aging is a decrease in NAD⁺ levels in the body, as an increase in NAD⁺ levels prevents skin aging phenotypes. Nicotinamide mononucleotide (NMN) is a precursor of NAD⁺ in the salvage pathway and the primary source of NAD⁺ in mammals.

This Study Aimed to Evaluate the Permeability, Functionality, and Stability of NMN in Cosmetics.

The permeation of NMN contained in a yeast-fermented filtrate (YFF) was evaluated in vitro using artificial skin membranes (Strat-M). Localization of NMN in the membrane was detected by MALDI-imaging mass spectrometry (MALDI-IMS) analysis. Collagen production in dermal fibroblasts was determined using Collagen Type I pro (ELISA). The analysis of the NMN degradation reaction and the determination of the half-life of NMN in the YFF were performed using high-performance liquid chromatography.

NMN Permeated and Was Detected Only in the Papillary Dermis Region of the Membrane by MALDI-IMS. Furthermore, Collagen Type 1 Production Was Increased in Human Fibroblasts When Treated With NMN. On the Other Hand, the NMN Degradation Reaction Was a First-Order Reaction, and the Half-Life of NMN in the YFF Was Approximately 7 months at 20°C. These Results Suggest That NMN Was Relatively Stable in the YFF and Did Not Reach the Subcutaneous Tissue, and That NMN Increased Collagen Production by Fibroblasts in the Papillary Dermis.

NMN in the YFF permeated artificial skin membranes, and NMN contained in YFF enhanced collagen Type 1 production in fibroblasts. Therefore, the YFF, containing NMN, may be a potential cosmetic ingredient.