NF-E2 related factor 2 (Nrf2) is a key transcription factor that plays a pivotal role in endogenous protection against oxidative stress. However, the role of Nrf2 in visual disorders remains unclear. It has been reported that oxidative stress is thought of as one of the causes of glaucoma. Here, we investigate whether the function of Nrf2 in oxidative stress-induced retinal ganglion cell (RGC) death. This study used adult male Nrf2 deficient mice (Nrf2 KO) and age-and sex-matched wild-type (WT) mice. We dissociated and purified N-4-[4-didecylaminostryryl]-N-methyl-pyridinium iodide-labeled RGCs with fluorescence-activated cell sorting, and tried to detect the Nrf2 and Keap1 genes. In the absence of nerve crush (NC), the number of RGCs in Nrf2 KO mice was almost same as that in WT mice. 1-(2-cyano-3-, 12-dioxooleana-1, 9 (11)-dien-28-oyl) imidazole (CDDO-Im), an Nrf2 activator, prevented NCinduced loss of RGCs in WT mice. Seven days after NC, without treatment, the number of RGCs in Nrf2 KO mice was significantly lower than in WT mice. In addition, after CDDO-Im treatment, quantitative RT-PCR showed increased expression of antioxidant and phase II detoxifying enzymes. These results suggest that up-regulation of Nrf2 signaling after CDDO-Im treatment may be a novel therapeutic strategy for the protection of RGCs, especially in glaucoma.

Glaucoma is an ocular disease characterized by progressive retinal ganglion cell (RGC) death caused by axonal injury. However, the underlying mechanisms involved in RGC death remain unclear. In this study, we investigated changes in the transcriptome profile following axonal injury in mice (C57BL/6) with RNA sequencing (RNA-seq) technology. The experiment group underwent an optic nerve crush (ONC) procedure to induce axonal injury in the right eye, and the control group underwent a sham procedure. Two days later, we extracted the retinas and performed RNA-seq and a pathway analysis. We identified 177 differentially expressed genes with RNA-seq, notably the endoplasmic reticulum (ER) stress-related genes Atf3, Atf4, Atf5, Chac1, Chop, Egr1 and Trb3, which were significantly upregulated. The pathway analysis revealed that ATF4 was the most significant upstream regulator. The antioxidative response-related genes Hmox1 and Srxn1, as well as the immune response-related genes C1qa, C1qb and C1qc, were also significantly upregulated. To our knowledge, this is the first reported RNA-seq investigation of the retinal transcriptome and molecular pathways in the early stages after axonal injury. Our results indicated that ER stress plays a key role under these conditions. Furthermore, the antioxidative defense and immune responses occurred concurrently in the early stages after axonal injury. We believe that our study will lead to a better understanding of and insight into the molecular mechanisms underlying RGC death after axonal injury.

These results suggest that LSFG measurements of waveform changes in ONH BF can differentiate healthy eyes from eyes with NTG, particularly those with mild NTG.

The results indicated that oral K-115 administration delayed RGC death. Although K-115 may be mediated through Nox1 downregulation, we found that it did not suppress ROS production directly. Our findings show that K-115 has a potential use in neuroprotective treatment for glaucoma and other neurodegenerative diseases.

TNFα plays a critical role in RD-induced photoreceptor degeneration. This pathway may become an important target in the prevention of RD-induced photoreceptor degeneration.