Background: UV radiation induces damage to human skin. Protection of skin by an oral photoprotective agent would have substantial benefits.
Objective: We investigated the photoprotective effect of oral administration of an extract of the natural antioxidant Polypodium leucotomos (PL).
Methods: A total of 9 healthy participants of skin types II to III were exposed to varying doses of artificial UV radiation without and after oral administration of PL (7.5 mg/kg). At 24 hours after exposure the erythema reaction was assessed and paired biopsy specimens were obtained from PL-treated and untreated skin.
Results: A significant decrease in erythema was found in PL-treated skin (P \.01). Histologically, PLtreated biopsy specimens showed less sunburn cells (P\.05), cyclobutane pyrimidine dimers (P\.001), proliferating epidermal cells (P \ .001), and dermal mast cell infiltration (P \ .05). A trend toward Langerhans cell preservation was seen.
Conclusion: Oral administration of PL is an effective systemic chemophotoprotective agent leading to significant protection of skin against UV radiation. (J Am Acad Dermatol 2004;51:910-8.)