 The aim of the study is to investigate the gene expression in human epidermis treated with ER4017 following sequential sellotapes strips after a 3 months ER4017 topical application. For this purpose, the modulation of gene expression is determined using a cDNA microarray technology. Stratum corneum disruption is performed following 3 months topical application on skin inner forearms. All the experiments are performed in 10 elderly healthy men. Volunteers are clinically and biophysically evaluated at baseline and then at monthly intervals or at 3 months respectively. 