An animal model for evaluation of topical photoprotection against ultraviolet A (320-380 nm) radiation.
Recent studies reporting UVA (ultraviolet A radiation 320-380 nm) as an integral part of the cumulative sun-induced damage in human skin have prompted an interest in developing effective UVA photoprotective agents. The development of such compounds has been impeded by the absence of a clinically relevant animal model for evaluating their efficacy. This report describes the development and use of such a laboratory animal system. Selected concentrations of oxybenzone (2-hydroxy-4-methoxybenzophenone) in vehicle (0.1% to 6%) or vehicle alone were applied to the depilated dorsal skin of 30 Hartley strain female albino guinea pigs. The skin was irradiated with solar simulated UVA from a xenon light source. Acute radiation-induced damage was assayed by erythema grading and inhibition of [3H]thymidine incorporation into epidermal DNA. Data from erythema grading studies indicated that a significant degree of photoprotection was achieved with 6%, 3%, and 1% solutions of benzophenone compared with the control vehicle; the 6% solution was significantly more photoprotective than the 3% and 1% solutions. A 6% solution afforded significant photoprotection when assayed by [3H]thymidine incorporation.
Chew
S
S
Department of Dermatology, Columbia University, College of Physicians and Surgeons, New York, New York 10032-3784.
DeLeo
V A
VA
Harber
L C
LC
D000287:Administration, Topical; D000818:Animals; D001577:Benzophenones / Q000008:administration & dosage / Q000627:therapeutic use*; D004247:DNA / Q000096:biosynthesis; D004261:DNA Replication / Q000528:radiation effects; D004195:Disease Models, Animal; D004305:Dose-Response Relationship, Drug; D004890:Erythema / Q000517:prevention & control; D005260:Female; D006168:Guinea Pigs; D011837:Radiation-Protective Agents; D012867:Skin / Q000528:radiation effects*; D013057:Spectrum Analysis; D014466:Ultraviolet Rays
D001577:Benzophenones; D011837:Radiation-Protective Agents; C047723:benzophenone; D004247:DNA