AQP3 and Alzheimer disease: In AD, an increase in the expression of aquaporin 3 has been observed, which may be related to water loss and the severity of the disease, in contrast to healthy individuals who maintain a balanced expression of this protein in the basal, horny, and spinous layers.5 The consequences of aquaporin 3 (AQP3) overexpression extend beyond cutaneous water retention as it becomes a target for the exacerbated immune response in AD inflammation.