TNF and glaucoma: In human and experimental models of glaucoma, activated astrocytes [23,24] and activated microglia [25,26] are detected in the ONH, and coincide with the increased expression of proinflammatory cytokines, such as IL-1β and TNFα, and neurotoxic mediators, such as nitric oxide (NO), reactive oxygen species (ROS), and glutamate [26,27].