vitamins C and E work synergistical

vitamins C and E work synergistically; when vitamin
E becomes oxidized by free radicals, it is regenerated
in the membrane by vitamin C.3-5
Previously, we have reported that L-ascorbic acid
applied topically to the skin reduces the photoinjury
produced by both UVB and UVA irradiation.6 The
critical role of
-tocopherol for the antioxidant protection
of the stratum corneum lipid bilayer and
protection against stratum corneum protein oxidation
has been recently reviewed.7 In this study, we
report on a combination of antioxidants, L-ascorbic
acid and
-tocopherol, optimized with regard to concentration
and pH for maximum photoprotective effects.
We demonstrate that this combination of vitamins
C and E is superior to either antioxidant alone.
The combination provides for a 4-fold protection
when compared with vehicle against erythema produced
by solar-simulated irradiation and inhibits the
generation or accumulation of thymine dimers in skin.