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Autoimmune optic neuritis (AON), a model of multiple sclerosis-associated optic neuritis, is accompanied by degeneration of retinal ganglion cells (RGCs) and optic nerve demyelination and axonal loss. In order to investigate the role of N-methyl-d-aspartate (NMDA) receptors in mediating RGC degeneration, upstream changes in the optic nerve actin cytoskeleton and associated deterioration in visual function, we induced AON in Brown Norway rats by immunization with myelin oligodendrocyte glycoprotein. Subsequently, visual acuity was assessed by recording visual evoked potentials and electroretinograms prior to extraction of optic nerves for western blot analysis and retinas for quantification of RGCs. As previously reported, in Brown Norway rats RGC degeneration is observed prior to onset of immune cell infiltration and demyelination of the optic nerves. However, within the optic nerve, destabilization of the actin cytoskeleton could be seen as indicated by an increase in the globular to filamentous actin ratio. Interestingly, these changes could be mimicked by intravitreal injection of glutamate, and similarly blocked by application of the NMDA receptor blocker MK-801, leading us to propose that prior to optic nerve lesion formation, NMDA receptor activation within the retina leads to retinal calcium accumulation, actin destabilization within the optic nerve as well as a deterioration of visual acuity during AON.
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http://dx.doi.org/10.1111/jnc.14980 | DOI Listing |
Metabolomics
September 2025
Laboratoire de Biochimie et Biologie Moléculaire, Centre Hospitalier Universitaire, Angers, France.
Introduction: The definition of Leber's hereditary optic neuropathy (LHON) does not take into account a preclinical phase during which the thickness of retinal nerve fiber layer (RNFL) is increased, prior to optic nerve atrophy, reducing the chances of visual recovery.
Objectives: Search for a metabolomic signature characterizing this preclinical phase and identify biomarkers predicting the risk of LHON onset.
Methods And Results: The blood and tear metabolomic profiles of 90 asymptomatic LHON mutation carriers followed for one year will be explored as a function of RNFL thickness and compared to those of a healthy control.
J Glaucoma
September 2025
Hamilton Glaucoma Center, Shiley Eye Institute, Viterbi Family Department of Ophthalmology, University of California San Diego, La Jolla, CA, United States.
Precis: Artificial intelligence applied to OCTA images demonstrated high accuracy in estimating 24-2 visual field maps by leveraging information from pararpapillary area.
Purpose: To develop deep learning (DL) models estimating 24-2 visual field (VF) maps from optical coherence tomography angiography (OCTA) optic nerve head (ONH) en face images.
Methods: A total of 3148 VF OCTA pairs were collected from 994 participants (1684 eyes).
Am J Ophthalmol
September 2025
Singapore Eye Research Institute, Singapore National Eye Centre, Singapore; Duke-NUS Graduate Medical School, Singapore; Department of Ophthalmology, Emory University School of Medicine, Emory University; Department of Biomedical Engineering, Georgia Institute of Technology/Emory University, Atlanta
Purpose: To characterize the 3D structural phenotypes of the optic nerve head (ONH) in patients with glaucoma, high myopia, and concurrent high myopia and glaucoma, and to evaluate their variations across these conditions.
Design: Retrospective cross-sectional study.
Participants: A total of 685 optical coherence tomography (OCT) scans from 754 subjects of Singapore-Chinese ethnicity, including 256 healthy (H), 94 highly myopic (HM), 227 glaucomatous (G), and 108 highly myopic with glaucoma (HMG) cases METHODS: We segmented the retinal and connective tissue layers from OCT volumes and their boundary edges were converted into 3D point clouds.
Am J Ophthalmol
September 2025
Bascom Palmer Eye Institute, University of Miami, Miami, FL, USA. Electronic address:
Purpose: To compare retinal ganglion cell (RGC) loss in glaucoma suspect eyes with diffuse versus localized neuroretinal rim loss at the time of the first confirmed visual field defect.
Design: Prospective observational cohort study.
Subjects: Fifty-three glaucoma suspect eyes and 124 healthy eyes.
Vestn Oftalmol
September 2025
Krasnov Research Institute of Eye Diseases, Moscow, Russia.
Primary open-angle glaucoma (POAG) is characterized by chronic progressive damage to the retinal ganglion cell layer (GCL) and their axons, leading to gradual visual function loss. Currently, the gold standards for structural and functional assessment of the retina in glaucoma are static automated perimetry (SAP) and optical coherence tomography (OCT). However, in clinical practice, data from SAP and OCT may be insufficient to reliably determine the stage of glaucomatous optic neuropathy, monitor its progression, or differentiate it from other causes of visual dysfunction.
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