Many changes related to aging at the cellular level may be due to the physiological condition of mitochondria. One of the most common types of damage of mtDNA is the so-called "common deletion" referring to a deletion of 4977 base pairs. In the skin cells this phenomenon probably is caused by oxidative damage of mtDNA induced by UV. The present study was aimed at evaluating the effect of the antioxidant L-ergothioneine on UV-induced damage in skin cells. The effect of L-ergothioneine on the reduced glutathione level was studied. The presence of the "common deletion" in human fibroblasts irradiated with UVA and treated with L-ergothioneine was evaluated by a polymerase chain reaction. We have demonstrated that L-ergothioneine enhanced the level of reduced glutathione and protected cells from the induction of a photoaging-associated mtDNA "common deletion". In view of our results, L-ergothioneine could be an effective skin care and anti-photoaging ingredient.

The results of this study show that both complementary technologies (Visioscan and Primos) are appropriate for characterizing the skin surface and could be useful in testing the efficacy of anti-aging properties. There are some measurements which are unique to just one method, none, however, seems to be significantly more useful for efficacy testing than the other.