The Effects of Aging and Injury on the Murine Ependymal Barrier and Subventricular Zone

Previous research has shown that numerous age-related changes occur in the subventricular zone (SVZ) and diminish the neurogenic output of the region. Here, various agerelated changes in the structure of the lateral ventricle, the ependymal barrier, and the SVZ were examined. It was found that the walls of the lateral ventricles move together, adhere, and eventually fuse. This results in a degradation of the SVZ. Other changes associated with aging were found, including ependymal cell stretching, heightened, ependymal repair, changes in CSF flow velocity and dynamics, and altered ependymal cell polarity. These changes may be related to the process of intraventricular fusion. Similar age-related changes did not occur in other parts of the ventricular system. The effects of injuries, including repetitive, mild traumatic brain injury (rmTBI) and Neuraminidase injections were also investigated. Preliminary studies on rmTBI did not produce an effect on the volume of the lateral ventricle, but did increase the prevalence of intraventricular fusion. However, further analysis is needed. Neuraminidase injection resulted in a significant increase in the volume of the lateral ventricles. Taken together, these results demonstrate the lateral ventricle’s unique susceptibility to changes associated with the aging process.