Aquaporin 1 (AQP1) is a water channel protein that facilitates rapid water transport across cell membranes. In the central nervous system, AQP1 is expressed in choroid plexus epithelial cells, where it plays a crucial role in cerebrospinal fluid (CSF) production and brain water homeostasis.
AQP1 forms a selective water channel that allows rapid transmembrane water movement while excluding ions and other solutes:
AQP1 is critically involved in brain edema formation and resolution. Following ischemic stroke or traumatic brain injury, AQP1 expression increases in choroid plexus, contributing to CSF overproduction and subsequent edema[4]. AQP1 inhibitors are being investigated as potential therapies for cytotoxic edema.
In neuroinflammatory conditions, AQP1 expression is modulated in various brain cell types. Studies suggest AQP1 plays a dual role in both promoting and resolving neuroinflammation depending on the context[5].
Following cerebral ischemia, AQP1 upregulation in the choroid plexus contributes to edema formation. AQP1 modulators may provide neuroprotection by reducing water accumulation in the brain[6].
AQP1 represents a target for treating brain water balance disorders: