A Review: Role of Ultraviolet Radiation in Age-Related Macular Degeneration

Abstract

Age-related macular degeneration (AMD) is a leading cause of blindness in the western world. The retina is highly susceptible to photochemical damage from continuous exposure of light and oxygen. The cornea and the lens block a major portion of the ultraviolet (UV) radiation from reaching the retina (<295 nm). The relationship between UV light exposure and AMD is unclear, although short wavelength radiation and the blue light induce significant oxidative stress to the retinal pigment epithelium. Epidemiologic evidence indicates a trend toward association between severity of light exposure and AMD. In this review, we discuss type 1 and type 2 photochemical damage that occurs in response to UV exposure. We examine the impact of different doses of exposure to UV radiation and the subsequent production of oxidative stress in AMD. Local and systemic protective mechanisms of the retina including antioxidant enzymes and macular pigments are reviewed. This article provides a review of possible cellular and molecular effects of UV radiation exposure in AMD and potential therapies that may prevent blindness resulting from this disease.

Corneal crosslinking in Pasteurella multocida –induced severe keratitis

“…This is known to be a risk for age-related macular degeneration, primarily because of continuous exposure to light. 16 Riboflavin also protects the cornea from dehydration and thereby reduces the possibility of stromal scarring. The decrease in corneal thickness can be as much as 25%.…”

UV-induced retinal proteome changes in the rat model of age-related macular degeneration

“…It has been previously shown that short wavelength radiation and the blue light induce significant oxidative stress to the retinal pigment epithelium [25]. Oxidative and radical damages can alter functions of metabolic enzymes such as creatine kinase (CK), whose expression was reduced in both, UVA and UVB exposed rat retina.…”

Review of nutrient actions on age-related macular degeneration

“…Oxygen exacerbates this damage via free-radical chain reactions [10,11]. This photochemical damage typically involves a compromised region in the macula in patients with AMD.…”

“…An increase in the intake of these carotenoids may modify the overall risk of AMD via the protection of retinal tissues from photo-oxidative damage. In fact, the macular pigment contains lutein and zeaxanthin, which protects the photoreceptor cell layer from light damage by filtering blue light [11,13]. Some of the dietary sources of lutein and zeaxanthin have been largely investigated as a protective factor in AMD.…”

“…Some of the dietary sources of lutein and zeaxanthin have been largely investigated as a protective factor in AMD. Primary studies have focused on the dietary intake of carotenoids, which is obtained from vegetables (eg, kale, spinach, and Brussels sprouts) [11,14], as well as supplements. As expected, however, the dietary contribution of lutein and zeaxanthin is largely dependent on population and dietary habits [15].…”