Polypodium leucotomos extract to decrease UV-induced damage: Exposure of human skin to sunlight containing UVA and UVB radiation exposes the skin to deleterious effects such as sunburn, immune suppression, pigmentary changes, photoaging and skin cancer. The mechanism of such cutaneous damage induction is complex, but can be broadly divided into direct oxygen-dependent damage through absorption of photons, and oxidative damage caused by formation of free radicals and reactive oxygen species. This is why antioxidants have been increasingly studied as inhibitors or quenchers of UV-induced cutaneous damage.
Currently the most widely used method of protection against UVinduced damage is the use of topical sunscreens enriched with UV-absorbing chemicals. Middelkamp-Hup et al, on the other hand, believe that a systemic photoprotective agent would provide uniform total body surface protection without the variance in protection some researchers have observed with topical sunscreens. Middelkamp-Hup et al have studied the use of Polypodium leucotomos (PL) extract to decrease UVinduced damage to human skin.4 In this study nine healthy participants of skin types II to III were exposed to varying doses of artifi cial UV radiation without and after oral administration of 7.5 mg/kg of PL These investigators report that a signifi cant decrease in erythema was found in the PL-treated skin and conclude that oral administration of PL is an effective systemic chemo protective agent leading to signifi cant protection of the skin against UV radiation. (I guess marketing this type of product would require a New Drug Application.)
Excerpt Only This is a shortened version or summary of the article that appeared in the Mar. 1, 2005 issue of Cosmetics & Toiletries magazine. The full content is not currently available online.