OPA1 and glaucoma: The deregulation of polyamines (putrescine, spermine and spermidine) metabolism, also observed in the optic nerves of the Opa1+/− mouse model (36), in LHON fibroblasts (34) and in glaucoma patients (37), is known to be related with mitochondrial deficiency, and plays a crucial role in the post-translational processing of the eIF5A translation factor, by activating the protein translation activity (38).