AQP4 and Alzheimer disease: We found that exogenous OT can realize efficient Aβ clearance from the brain, which might be due to its positive effects on the structure and function of both glymphatic and meningeal lymphatic systems, including the improvements in cerebral hemodynamics, AQP4 polarization, meningeal lymphangiogenesis and transcriptional profiles, thus greatly restoring cognitive function in AD mice.