Niacinamide, an amide of vitamin B3 (niacin), is a hydrophilic endogenous substance. Its effects after epicutaneous application have long been described in the literature. Given a sufficient bioavailability, niacinamide has antipruritic, antimicrobial, vasoactive, photo-protective, sebostatic and lightening effects depending on its concentration. Within a complex metabolic system niacinamide controls the NFκB-mediated transcription of signalling molecules by inhibiting the nuclear poly (ADP-ribose) polymerase-1 (PARP-1). Niacinamide is a well-tolerated and safe substance often used in cosmetics.
In 2018 Philips and co-workers showed that nicotinamide and its derivatives stimulated fibrillar collagen and heat shock protein in dermal fibroblasts. Ultraviolet radiation stimulated elastin but inhibited fibrillin 1 and 2 in dermal fibroblasts. In this study they showed that topical niacin and its derivative stimulated the expression of elastin, fibrillin 1 and 2 in nonirradiated and UVA irradiated fibroblasts and directly inhibited both elastase and metalloproteinase activity (Philips et al 2018). In another study a niacinamide derivative, N-nicotinoyltyramine (NNT) inhibited melanin production in B16F10 murine melanoma cells stimulated with α-melanocyte stimulating hormone (α-MSH) acting as an inhibitor of microphthalmia-associated transcription factor (MITF) and tyrosinase expressions in B16F10 cells. Due the ability of niacinamide in the inhibition of melanogenesis it has desirable whitening effects and would be expected to lighten the skin and also even out pigment (Kim et al 2015).
Furthermore, the topical applications of 0.05% and 0.1% NND induced skin lightening and decreased melanin production without affecting the viability and morphology of melanocytes and overall tissue histology. The vitamin also maintained high antioxidant activities and as well as a concentration of 0.1% there was no evidence for skin irritation or sensitization (Kim B et al 2011)