Research demonstrates that senescence is associated with tissue and organ dysfunction, and the eye is no exception. Sequelae arising from aging have been well defined as distinct clinical entities and vision impairment has significant psychosocial consequences. Retina and adjacent tissues like
retinal pigmented epithelium and choroid are the key structures that are required for visual perception. Any structural and functional changes in
retinal layers and blood retinal barrier could lead to
age-related macular degeneration,
diabetic retinopathy, and
glaucoma. Further, there are significant
oxygen gradients in the eye that can lead to excessive
reactive oxygen species, resulting in endoplasmic reticulum and mitochondrial stress response. These radicals are source of functional and morphological impairment in
retinal pigmented epithelium and retinal ganglion cells. Therefore, ocular diseases could be summarized as disturbance in the redox homeostasis.
Hyperhomocysteinemia is a risk factor and causes vascular occlusive disease of the retina. Interestingly,
hydrogen sulfide (H2S) has been proven to be an effective
antioxidant agent, and it can help treat diseases by alleviating stress and
inflammation. Concurrent
glutamate excitotoxicity, endoplasmic reticulum stress, and microglia activation are also linked to stress; thus, H2S may offer additional interventional strategy. A refined understanding of the aging eye along with H2S biology and pharmacology may help guide newer
therapies for the eye.