Experimental models to study oxidative stress in glaucoma: integrating in vitro, in vivo, and clinical studies

Glaucoma is a complex optic neuropathy and the leading cause of permanent blindness worldwide. Elevated intraocular pressure (IOP) is the major modifiable risk factor for this disease. Growing evidence suggests that oxidative stress and reactive oxygen species (ROS) are key mediators of retinal ganglion cell (RGC) death and optic nerve (ON) damage. In this review, we summarize experimental models that are routinely used to study oxidative stress in glaucoma and discuss the translational value of each model system for biomarker discovery and treatment development. This narrative review focuses on studies that emphasize experimental and clinical models relevant to oxidative stress in glaucoma. Primary experimental and clinical studies that directly investigated pathways of oxidative stress in glaucoma models were included for contextual synthesis. In vitro systems such as TM cells, RGCs, and induced pluripotent stem cell (iPSC)-derived models enable controlled conditions to study cellular processes of ROS-induced stress and to screen potential therapeutic agents. Three-dimensional culture systems provide even more physiological insights by replicating retinal development, organization, and function. In vivo models include microbead-induced ocular hypertension (OHT), episcleral vein cauterization (EVC), and genetic models, allowing for the study of oxidative stress in the context of raised IOP, neuroinflammation, and vascular dysregulation. Findings from human donor tissues and clinical biospecimens provide translational support for experimental models by showing oxidative damage in glaucomatous eyes. Across model systems, oxidative stress is associated with glaucoma-related cellular and molecular changes, including mitochondrial dysfunction, neuroinflammation, synaptic instability, and altered neurotrophic signaling. This review provides a structured, model-based overview of how oxidative stress can be investigated across in vitro, in vivo, and clinical systems for glaucoma research. Although it is not intended to be fully comprehensive, it highlights key experimental platforms that can guide model selection for studying ROS-mediated mechanisms and developing neuroprotective strategies.