Another research demonstrated that tau can be cleaned from the brain through the paravascular pathway too, and the deletion of the AQP4 gene led to decreased waste-cleaning function, and elevated P-tau level in traumatic brain injury mice, increased axonal degeneration, neuroinflammation, and exacerbation of posttraumatic cognitive deficits were observed [33]. Here, AQP4 is linked to Cognitive impairment.