Reactive astrogliosis is a response to CNS trauma or disease is characterized by astrocyte activation, proliferation, up regulation of the structural intermediate filament protein glial fibrillary acidic protein (GFAP), cellular hypertrophy, and development of a pronounced stellate morphology (Lee et al., 2000; Liu et al., 2000; Messing and Brenner, 2003). Both beneficial and detrimental elements of astrogliosis have been described. In spinal cord injury (SCI), the stellate processes of astrocytes interdigitate to form a dense plexus that creates a physical and molecular barrier to nerve regeneration (Fitch and Silver, 2008; Ridet et al., 1997). Chronic demyelinated plaques in multiple sclerosis are also characterized by a dense network of larger than normal stellate astroglia (Holley et al., 2003). Activated astrocytes may help drive inflammatory responses by producing a variety of cytokines and chemokines, and by virtue of their ability to present antigens to T-cells (Hariri et al., 1994). With astrogliosis, the normal physiologic and protective functions of astrocytes may also be diminished or lost. …show more content…
In addition, astrocytic end feet, which together with endothelial cell