Nicotinamide pretreatment may protect skin from UVB exposure

Nicotinamide, a form of vitamin B3, could protect skin cells from damaging, cancer-causing ultraviolet B exposure, according to a presentation at the European Academy of Dermatology and Venereology virtual congress.

“Nonmelanoma skin cancers include basal cell carcinoma and squamous cell carcinoma. ... The main risk factor is ultraviolet radiation that causes skin cancers,” Lara Camillo, a research student from the dermatological unit of AOU Maggiore della Carità, Novara, Italy, said. “The main consequences of ultraviolet radiation on epidermal keratinocytes is the activation of the reactive oxygen species, which can directly damage the DNA.”

Cells of non-melanoma squamous cell cancer were isolated and treated with three concentrations of nicotinamide (5 µM, 25 µM and 50 µM) for 18, 24 and 48 hours before 400 mJ/cm² UVB exposure in this study.

Treatment with 25 µM 24 hours before UV exposure protected from the effects of UV-induced oxidative stress and DNA damage. In addition, DNA repair was enhanced, antioxidant expression decreased, and local inflammation was blocked.

“In chronic irradiated human primary keratinocytes, nicotinamide has no significant effect; however, in acute ultraviolet irradiated keratinocyte, nicotinamide can block the damage effect of UV radiation,” Camillo said.