Lutein Protects Retinal Health

VRP Staff

The carotenoid lutein protects against macular degeneration through its ability to act as an anti-inflammatory, new research indicates.

Past studies have shown that lutein is a major nutrient in the retina. It acts as an antioxidant and protects against macular degeneration and retinal degenerative disease. However, lutein’s mechanism is not clear in retinal degeneration, and a role for lutein is not known in ischemic injury when the eye is deprived of its blood flow.

In the current study, researchers injected lutein into the vitreous of the animals’ eyes then induced ischemia and high intraocular pressure in the rat retinas. They then examined the animals to determine the effect of lutein on ischemic retinal cell death and retinal degeneration. Markers of inflammation such as neuronal nitric oxide synthase (nNOS) and cyclo-oxygenase-2 (COX-2) were measured at various times after retinal ischemia.

Results indicated that inflammatory markers were increased early in ischemic control retinas. In the lutein-treated retinas, however, these increases were inhibited. In addition, lutein’s inhibitory effect was dose dependent. Furthermore, lutein inhibited ischemia-induced cell death. In fact, lutein-injected ischemic retinas appeared similar to normal retinas.

“These results suggest,” the researchers wrote, “that a supplement with lutein may have the potential to inhibit ischemic cell death by this mechanism in the neural retina.”

Reference:
Choi JS, Kim D, Hong YM, Mizuno S, Joo CK. Inhibition of nNOS and COX-2 expression by lutein in acute retinal ischemia. Nutrition. 2006 Jun;22(6):668-71. Epub 2006 May 2.