Peroxiredoxin 6 delivery attenuates TNF-α-and glutamate-induced retinal ganglion cell death by limiting ROS levels and maintaining Ca²⁺ homeostasis

Higher expression of reactive oxygen species (ROS) is implicated in neurological disorders. A major event in glaucoma, the death of retinal ganglion cells (RGCs), has been associated with elevated levels of glutamate and TNF-α in the RGCs' local microenvironment. Herein we show that the transduction of Peroxiredoxin 6 (PRDX6) attenuates TNF-α- and glutamate-induced RGC death, by limiting ROS and maintaining Ca²⁺ homeostasis. Immunohistochemical staining of rat retina disclosed the presence of PRDX6 in RGCs, and Western and real-time PCR analysis revealed an abundance of PRDX6 protein and mRNA. RGCs treated with glutamate and/or TNF-α displayed elevated levels of ROS and reduced expression of PRDX6, and underwent apoptosis. A supply of PRDX6 protected RGCs from glutamate and TNF-α induced cytotoxicity by reducing ROS level and NF-κB activation, and limiting increased intracellular Ca²⁺ influx. Results provide a rationale for use of PRDX6 for blocking ROS-mediated pathophysiology in glaucoma and other neuronal disorders.