Research Paper Volume 3, Issue 4 pp 407—416

Figure 5. Dermabrasion upregulates IGF-1 expression and restores the appropriate UVB response to geriatric skin. Small areas of dermabraded and untreated skin on geriatric volunteers described in Fig. 2 were irradiated with UVB (dose of 350 J/m²). Twenty-four hours post-UVB, the irradiated skin was biopsied. (A) Total mRNA was isolated and the relative level of IGF-1 expression was determined by quantitative PCR (normalized to actin expression). Asterisk indicates statistically significant differences from control values (p <0.006, two-tailed t-test). (B) Sections of biopsies were stained with antibodies to Ki67 and thymine dimers (TD). The number of dual Ki67(+):TD(+) basal keratinocytes were determined for both sets of biopsies. Asterisk indicates statistically significant differences from control values (p <0.05, two-tailed t-test).