Elevated IOP in glaucoma induces reduction of cytochrome c oxidase (COX) activity, mitochondrial fission, mitochondrial matrix swelling, cristae depletion, triggers release of optic nerve atrophy type-I (OPA1), and induces subsequent apoptotic cell death in differentiated RGC-5 cells [77,78] (Figure 4). This evidence concerns the gene OPA1 and glaucoma.