4/10/2023 0 Comments Mars density![]() It is also not entirely clear in which tissue compartments the MP is stored. Our recent study using optical coherence tomography supports such a concept. These results support the idea that genetically determined structural components are responsible for the storability and availability of MP in the macula and that successful supplementation with lutein or zeaxanthin always depends on macular microanatomy. such ring-like patterns are highly inheritable and constant in individuals. Interestingly, ring-like distributions of MPOD appear not to be affected by supplementation of lutein/zeaxanthin. ![]() These results are compatible with the hypothesis that MP is stored in retinal tissue structures that are characteristic of an individual and that determine also the spatial patterns of MPOD distribution : supplementation can therefore increase MPOD levels only where such storage facilities were pre-existing. Supplementation did not produce an increase in areas where MPOD had been lacking at baseline. demonstrated that, after oral supplementation with lutein and zeaxanthin, an increase in MPOD can be detected only in areas where MPOD had been measurable before in persons with macular telangiectasia. On the other hand, a reduced availability and potentially also storability of carotenoids in the retina may independently lead to the degeneration of functional retinal tissue. It seems conceivable that degenerative processes cause impairments in transport and storage of lutein and zeaxanthin resulting in decreased MP in the retina. There is presently some debate as to whether a loss of MP is the result of progressed AMD or whether it is a cause. Commonly, lutein meso-zeaxanthin and zeaxanthin, known to accumulate in the macula as macular pigment (MP) and having antioxidant and light-screening properties for short wavelengths, are hypothesized to protect the eye against the development of various degenerative retinal diseases, including AMD. The level of macular pigment in the central retina is thought to also have an impact on AMD, however, the precise roles and mechanisms of this process are not yet clearly understood. Recent research has shown that the occurrence and progression of age-related macular degeneration (AMD), the leading cause of legal blindness among the elderly population in industrialized countries, is mainly influenced by demographic, environmental and genetic factors. ![]() The persistence of ring-like MPOD distributions over time seems to suggest their determination by anatomical structures. Significant MPOD rises in perifoveal regions probably indicate effects of lutein containing supplements. Overall, the magnitude and spatial arrangement of MPOD was remarkably stable over time in elderly eyes. A ring-like spatial distribution of MPOD persisted in over 80 % of the affected eyes. Early AMD at baseline and ring-like MPOD distribution did not significantly impact on MPOD changes over time. Serum concentrations of lutein at follow-up, presumably reflecting recent intake of antioxidant supplements, raised MPOD levels significantly at 1.0° and 2.0° (both p < 0.01) but not in the central fovea. Multivariate analyses, adjusting for sex, body mass and carotenoid supplement intake, revealed that MPOD increments, at any distance from the fovea, were slightly less pronounced in older eyes. After a median follow-up time of 3.96 years, the MPOD averaged over all eyes was slightly raised at the central fovea (from 0.658 to 0.670 D.U. Early AMD was present in 150 study eyes (39.5 %) and a ring-like distribution of MPOD was found in 87 study eyes (22.9 %). The study participants’ mean age at baseline was 70.5 years. Changes were assessed with mixed linear models. MP optical density (MPOD) was measured in density units (D.U.) at eccentricities of 0.25°, 0.5°, 1.0° and 2.0° from the fovea using dual-wavelength autofluorescence ring-like MP distributions were identified from MP density profiles. The study included 380 eyes from 237 participants of the Münster Ageing and Retina Study cohort which were free of advanced stages of AMD. We investigated prospectively in eyes of elderly individuals how magnitude and spatial distribution of MP had changed after 4 years. Macular pigment (MP) has been related to the occurrence of age related macular degeneration (AMD).
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