Figure 6.
Abrogation of UV-A1–induced antifibrotic responses in skin with darker pigmentation. Based on L* (luminescence) values, 28 healthy subjects were stratified according to skin pigmentation as light (n=8), medium (n=8), or dark (n=12). Skin was then exposed to the indicated UV-A1 doses. Biopsies were performed 24 hours later, and the indicated transcripts were assessed by real-time polymerase chain reaction: type I procollagen (A), type III procollagen (B), matrix metalloproteinase (MMP) 1 (C), MMP-3 (D), and MMP-9 (E). Data are presented as mean fold change relative to untreated skin (normalized to 1). Error bars represent SEM. *P<.05 for light skin vs untreated skin. †P<.05 for medium skin vs untreated skin.