Transcriptional changes in organoculture of full-thickness human skin following topical application of all-trans retinoic acid

Abstract

In this study, we developed an organoculture of human skin to investigate the effect of topical applied all-trans retinoic acid using a gene array approach. We could by using this approach confirm previous studies on genes activated by RA in keratinocyte monocultures and also provide new insights on genes that are relevant to RA-activation in human skin. The results in the present study show this model represent a valuable pre-clinical model for studying the effects of retinoids in skin.

Keywords: acne; cell culture; dandruff; elisa; genomics; proteomics; rosacea; skin culture; striae skin physiology; structure.

Figure 1

RA does not affect the viability of skin explants. Explants were exposed for 24 h to topical RA treatment (Aberela®) at a concentration of 0.05%. Data are expressed as the mean ± SEM of three independent experiments on three explants from different donors. Two-way ANOVA test was used for statistical analysis.

Figure 2

Heat map of hierarchical clustering of 93 genes in RA-treated explants compared with placebo. Hierarchical clustering was performed using the genesis software , with default settings (e.g. Euclidian distance, average linkage) of genes differentially expressed more than less than twofold, that is, 93 genes. Green indicates reduced expression, black indicates the unaltered expression, and red indicates increased expression in RA-treated as compared to placebo-treated explants (n = 3). The colour scale bar is shown at the top of each figure.Cluster analyses of altered genes involved in metabolism genes and development genes. Hierarchal clustering analysis was performed in both the gene (row) and experiment (column) dimension. Yellow arrows indicate genes enriched in gene annotation clustering (David Bioinformatics) which resulted in cluster 1 representing genes involved in metabolism (Enrichment score 3.6). 5 genes of 10 genes in the metabolism cluster were defining genes involved in metabolism of RA. Blue arrows indicate genes enriched in cluster 2 which were defined as involved in development (Enrichment score 2.0) by David Bioinformatics.

Figure 3

Validation of microarray findings by qPCR analysis. qPCR confirmed upregulation of CYP26B1 (1.52-fold), HBEGF (3.22-fold) and DHRS9 (3.53-fold) by RA in explants from different donors. Wilcoxon signed-rank test used for statistical analysis. Data are presented as relative concentration of gene expression (mean + SD, n = 9).