The retina of the eye is composed of neurons, glial cells (microglia and astrocytes), complex networks of connections, and specialized light receptor cells. The retina develops along with and is directly connected to the brain. As we age, the retina suffers from the same types of degeneration as the rest of the nervous system.

Like the brain and spinal cord, the retina’s microglial immune cells trigger the destruction. Immunoexcitotoxicity occurs within the retina in cases of diabetes, macular degeneration, glaucoma, retinitis pigmentosa, and other retinal diseases. Of all these diseases, the most common is damage associated with diabetes (diabetic retinopathy). And the greatest damage occurs in retinal ganglion cells, mainly secondary to destruction of small arteries within the retina (microangiopathy).

The central mechanism that causes damage appears to be chronic activation of retinal microglia, which release high levels of excitotoxins and inflammatory cytokines. This activation generates very high levels of free radicals and lipid peroxidation products that seep into the surrounding retinal tissue, causing widespread destruction and eventually blindness.

One study found that saffron extract powerfully protected the retina from damage caused by diabetes In the case of glaucoma — which causes immunoexcitotoxicity that is triggered either by high levels of pressure within the eyeball or other factors — saffron extract has been shown to provide considerable protection against suffering retinal damage.

Studies have also shown that saffron extract protects the retina by raising the levels of antioxidants such as glutathione and superoxide dismutase (SOD). This shields the retina against a number of diseases, and can reduce irritating floaters that plague many people.