http://www.ncbi.nlm.nih.gov/pubmed/21245404Nutritional Manipulation of Primate Retinas. V: Effects of Lutein, Zeaxanthin and n--3 Fatty Acids on Retinal Sensitivity to Blue Light Damage.
Barker FM 2nd, Snodderly DM, Johnson EJ, Schalch W, Koepcke W, Gerss J, Neuringer M.
Pennsylvania College of Optometry at Salus University, Elkins Park, PA, USA;
Abstract
Purpose: Blue light photooxidative damage has been implicated in the etiology of age-related macular degeneration (AMD). The macular pigment xanthophylls lutein (L) and zeaxanthin (Z) and n--3 fatty acids may reduce this damage and lower AMD risk. We investigated effects of lifelong absence of xanthophylls followed by L or Z supplementation, combined with effects of n--3 fatty acid deficiency, on acute blue light photochemical damage. Methods: Subjects included eight rhesus monkeys with no lifelong intake of xanthophylls and no detectable macular pigment. Of these, four had low n--3 fatty acid intake and four had adequate intake. Controls had typical L, Z, and n--3 fatty acid intake.
Retinas received 150 μm-diameter exposures of low-power 476 nm laser light either at 0.5 mm (∼2(o)) eccentricity, adjacent to the macular pigment peak, or parafoveally at 1.5 mm (∼6(o)). Exposures of xanthophyll-free animals were repeated after supplementation with pure L or Z for 22-28 weeks. Ophthalmoscopically visible lesion areas were plotted as a function of exposure energy, with greater slopes of the regression lines indicating greater sensitivity to damage.
Results: In control animals, the fovea was less sensitive to blue light damage than the parafovea. Foveal protection was absent in xanthophyll-free animals but evident after supplementation. In the parafovea, animals low in n--3 fatty acids showed greater sensitivity to damage than animals with adequate levels. Conclusions: After long-term xanthophyll deficiency, L or Z supplementation protected the fovea from blue light damage, whereas adequate n--3 fatty acid levels reduced damage in the parafovea.
http://www.ncbi.nlm.nih.gov/pubmed/20190863Acta Hortic. 2009 Aug 31;841:103-112.
Nutritional Interventions against Age-Related Macular Degeneration.
Bernstein PS.
Moran Eye Center, University of Utah School of Medicine, Salt Lake City, Utah, USA.
Abstract
Age-related macular degeneration (AMD) is the leading cause of irreversible visual loss in the developed world. This disease of the elderly robs them of central vision in one or both eyes leading to a devastating loss of the ability to drive, read, and recognize faces. In recent years, a number of novel treatments for the neovascular form of AMD (also known as "wet" or exudative AMD) have been introduced, and for the first time, the relentless downhill course of vision loss experienced by the majority of patients with this particularly malignant variant of AMD has been transformed to the stabilization and even improvement of vision in at least two-thirds of patients.
Likewise, the slower, more insidious form of AMD known as dry AMD which leads to geographic atrophy of the macula has become the focus of pharmaceutical firms' efforts for intervention. Unfortunately, all of these novel treatments have limitations, and they tend to be very expensive.
Thus, prevention of AMD is of paramount importance to reduce the healthcare burden of this blinding disorder. Accumulating evidence suggests that encouragement of increased consumption of fruits and vegetables rich in the xanthophyll carotenoids lutein and zeaxanthin is a simple, cost effective public health intervention that might help to decrease the incidence of AMD. In this review article, the scientific underpinnings for these nutritional recommendations will be surveyed.
PMID: 20190863
PMCID: PMC2826786Free PMC Article
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