Modulation of Corticotropin-Releasing Hormone Receptor Expression During In Vitro Keratinocyte Differentiation

Corticotropin-releasing hormone (CRH) and its receptors CRHR1 and CRHR2 are major actors in the stress response and are well established as components of the hypothalamic–pituitary–adrenal (HPA) axis. Evidence also suggests they are expressed in peripheral tissues and, more interestingly, in the skin. While CRHR1 expression in keratinocytes is documented in terms of presence or absence, data on CRHR2 remain sparse. Moreover, there is no detailed description of the exact localization of CRHR1/2 receptors within the different layers of the epidermis, leaving this question fully unexplored. To better understand the link between stress and skin disorders, we aimed to investigate the differential expression of CRHR1 and CRHR2 in keratinocytes, depending on their level of differentiation. In vitro results demonstrated that CRHR1 appears to be more abundant at early stages of differentiation and CRHR2 at more advanced stages.