TNF and low tension glaucoma: In normotensive glaucoma, deletion of the apoptosis signal-regulating kinase 1 (ASK1) gene suppresses the oxidative stress that is linked to glutamate-mediated excitotoxicity, increases survival of RGCs, and reduces the production of the pro-inflammatory cytokine tumor necrosis factor-alpha (TNF-α) by macrophages, microglia, and astrocytes [132,171].