Polypodium Leucotomos--An Overview of Basic Investigative Findings

Abstract

The use of Polypodium leucotomos, a species of fern, has been reported to be beneficial in the treatment of atopic dermatitis, vitiligo, and psoriasis, and for prevention of polymorphic light eruption, sunburn, and squamous cell carcinoma. We review the in vivo animal, in vitro human, and human clinical studies performed to help elucidate the actions of and biologic pathways affected by P. leucotomos. These results serve as the scientific rationale and basis for the protection and effectiveness afforded by P. leucotomos in cutaneous diseases.

Figure

Ten healthy adult volunteers initially underwent a punch biopsy for baseline common deletion measurement (26). One week later the volunteers were exposed to 2 and 3 times their MED with an area of skin shielded from exposure. Subjects were randomized to receive oral P. leucotomos 240 mg administered 8 and 2 hours before UV exposure. Twenty-four hours after UV, each subject underwent a second and a third punch biopsy of the irradiated areas and a fourth biopsy from the shielded area site and common deletion determinations were performed on all four biopsy specimens. At two times the MED, mean common deletion values in the untreated group increased by 159.7% over baseline while the mean common deletion values in the P. leucotomos-treated decreased by 42.3% (p=0.06). At three times the MED, those values increased 702.9% and 101.6%, respectively (p=0.07).