Decreased Calcium-Sensing Receptor Expression Controls Calcium Signaling and Cell-To-Cell Adhesion Defects in Aged Skin.

The calcium-sensing receptor (CaSR) drives essential calcium ion (Ca) and E-cadherin‒mediated processes in the epidermis, including differentiation, cell-to-cell adhesion, and epidermal barrier homeostasis in cells and in young adult mice. We now report that decreased CaSR expression leads to impaired Ca signal propagation in aged mouse (aged >22 months) epidermis and human (aged >79 years, donor age) keratinocytes. Baseline cytosolic Ca concentrations were higher, and capacitive Ca entry was lower in aged than in young keratinocytes.