A Novel In Vivo Model for Evaluating Agents That Protect Against Ultraviolet A-Induced Photoaging

The study developed a novel in vivo model using transgenic mice to evaluate agents that protect against UVA-induced photoaging. This model used a human elastin promoter linked to a CAT reporter gene to measure elastin gene induction. It showed that PUVA treatment significantly increased promoter activation, which was reduced by sunscreens, particularly those with SPF 15 and UVA filters. The combination sunscreen provided the greatest protection, reducing CAT activity to near baseline levels. This model proved effective for rapidly identifying and comparing compounds that protect against UVA-induced photoaging, despite differences between murine and human skin responses.