AbstractFerulic acid is a potent ubiquitous plant antioxidant. Its incorporation into a topical solution of 15% L-ascorbic acid and 1% a-tocopherol improved chemical stability of the vitamins (C þ E) and doubled photoprotection to solarsimulated irradiation of skin from 4-fold to approximately 8-fold as measured by both erythema and sunburn cell formation. Inhibition of apoptosis was associated with reduced induction of caspase-3 and caspase-7. This antioxidant formulation efficiently reduced thymine dimer formation. This combination of pure natural low molecular weight antioxidants provides meaningful synergistic protection against oxidative stress in skin and should be useful for protection against photoaging and skin cancer.Keywords: antioxidant/ferulic acid/photoprotection/vitamin C/vitamin EThe Journal of Investigative Dermatology 125:826 –832, 2005Fu-Hsiung Lin, Jing-Yi Lin, Ravindra D. Gupta, Joshua A. Tournas, James A. Burch, M. Angelica Selim, Nancy A. Monteiro-Riviere, James M. Grichnik, Jan Zielinski, and Sheldon R. Pinnell
