A form of vitamin B3 can protect skin cells from the effects of ultraviolet (UV) exposure which is the main risk factor for non-melanoma skin cancers, reveals new research.

Researchers in Italy isolated cells (human primary keratinocytes) from the skin of patients with non-melanoma skin cancers. These cells were treated with three different concentrations of nicotinamide (NAM) -- a form of vitamin B3 -- for 18, 24, and 48 hours and then exposed to UVB. Results showed that pre-treatment with 25 micron (M) of NAM 24 hours before UV irradiation protected the skin cells from the effects of UV-induced oxidative stress, including DNA damage.

NAM enhanced DNA repair, demonstrated by decreased expression of the DNA repair enzyme OGG1. Furthermore, it decreased antioxidant expression and blocked local inflammation by showing decreased nitric oxide (NO) release and reactive oxygen species (ROS) production, and reduced iNOS protein expression. "Our study indicates that increasing the consumption of vitamin B3, which is readily available in the daily diet, will protect the skin from some of the effects of UV exposure, potentially reducing the incidence of non-melanoma skin cancers," said Lara Camillo, a research student from the dermatological unit of AOU Maggiore della Carita, Novara, Italy. However, the protective effect of vitamin B3 is short-acting, so it should be consumed no later than 24 to 48 hours before sun exposure, she said during the 29th European Academy of Dermatology and Venereology virtual conference.

Non-melanoma skin cancers are the most common malignancies and are increasing worldwide. The main risk factor is UV radiation exposure, which damages the DNA, increases ROS production, activates local inflammation, and depletes cellular energy, leading to genomic instability and cell death.