Gene expression modulation assessed by quantitative PCR in fibroblasts of reconstructed skins exposed to UVA1.

Reconstructed skins were exposed to 20 or 40 J/cm2 UVA1 and recovered 2, 6 or 24 hours later. Expression of genes found modulated in the microarray study and/or representative of main functional families was analyzed by quantitative PCR in fibroblasts of reconstructed skin. Ratios of modulation induced by UVA1 exposure were calculated for each condition as the ratio of mean mRNA amount in UVA1 exposed samples to mean mRNA amount in sham exposed control samples (columns 2 to 7). Bold text indicate mean ratio values with significant differences between UVA1 exposed and control samples (p <0.05, Student's t test). All studied genes, except those underlined and those marked with an asterisk, were found modulated by UVA1 in microarray experiments, in fibroblasts. Underlined genes were not found modulated in microarray experiments but were of interest regarding UVA stress and photoageing. Asterisks indicate genes found modulated in keratinocytes but not in fibroblasts, in microarray experiments. ND, not detected.