title: Repeated short climatic change affects the epidermal differentiation program and leads to matrix remodeling in a human organotypic skin model.
abstract: Human skin is subject to frequent changes in ambient temperature and humidity and needs to cope with these environmental modifications. To decipher the molecular response of human skin to repeated climatic change, a versatile model of skin equivalent subject to "hot-wet" (40°C, 80% relative humidity [RH]) or "cold-dry" (10°C, 40% RH) climatic stress repeated daily was used. To obtain an exhaustive view of the molecular mechanisms elicited by climatic change, large-scale gene expression DNA microarray analysis was performed and modulated function was determined by bioinformatic annotation. This analysis revealed several functions, including epidermal differentiation and extracellular matrix, impacted by repeated variations in climatic conditions. Some of these molecular changes were confirmed by histological examination and protein expression. Both treatments (hot-wet and cold-dry) reduced the expression of genes encoding collagens, laminin, and proteoglycans, suggesting a profound remodeling of the extracellular matrix. Strong induction of the entire family of late cornified envelope genes after cold-dry exposure, confirmed at protein level, was also observed. These changes correlated with an increase in epidermal differentiation markers such as corneodesmosin and a thickening of the stratum corneum, indicating possible implementation of defense mechanisms against dehydration. This study for the first time reveals the complex pattern of molecular response allowing adaption of human skin to repeated change in its climatic environment.
authors.affiliation: Departement de Biologie, Université Claude Bernard Lyon I.
authors.forename: Laetitia-Barbollat
authors.initials: LB
authors.lastname: Boutrand
authors.affiliation: LabSkinCreations.
authors.forename: Amélie
authors.initials: A
authors.lastname: Thépot
authors.affiliation: CNRS UMR5305, Laboratoire de Biologie Tissulaire et d'Ingénierie Thérapeutique (LBTI), Lyon.
authors.forename: Charlotte
authors.initials: C
authors.lastname: Muther
authors.affiliation: LabSkinCreations.
authors.forename: Aurélie
authors.initials: A
authors.lastname: Boher
authors.affiliation: Laboratoires Clarins, Cergy-Pontoise.
authors.forename: Julie
authors.initials: J
authors.lastname: Robic
authors.affiliation: Laboratoires Clarins, Cergy-Pontoise.
authors.forename: Christelle
authors.initials: C
authors.lastname: Guéré
authors.affiliation: Laboratoires Clarins, Cergy-Pontoise.
authors.forename: Katell
authors.initials: K
authors.lastname: Vié
authors.affiliation: Banque de Tissus et Cellules, Hospices Civiles de Lyon, Lyon, France.
authors.forename: Odile
authors.initials: O
authors.lastname: Damour
authors.affiliation: Departement de Biologie, Université Claude Bernard Lyon I; CNRS UMR5305, Laboratoire de Biologie Tissulaire et d'Ingénierie Thérapeutique (LBTI), Lyon.
authors.forename: Jérôme
authors.initials: J
authors.lastname: Lamartine
keywords: climatic changes; collagen; organotypic tissue; skin; transcriptome