151
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Souied E, Le Tien V, Coscas G, Soubrane G. [Toward prevention of age-related macular degeneration]. J Fr Ophtalmol 2007; 30:449-55. [PMID: 17568337 DOI: 10.1016/s0181-5512(07)89624-0] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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152
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Fang IM, Yang CH, Yang CM, Chen MS. Linoleic acid-induced expression of inducible nitric oxide synthase and cyclooxygenase II via p42/44 mitogen-activated protein kinase and nuclear factor-kappaB pathway in retinal pigment epithelial cells. Exp Eye Res 2007; 85:667-77. [PMID: 17825288 DOI: 10.1016/j.exer.2007.07.021] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2007] [Revised: 07/14/2007] [Accepted: 07/25/2007] [Indexed: 11/17/2022]
Abstract
High linoleic acid (LA) intake is known to correlate with age-related macular degeneration (AMD), but the molecular mechanisms remain unclear. This study was conducted to investigate the effects of LA on expression of inducible nitric oxide synthase (iNOS) and cyclooxygenase II (COX-2) and their associated signaling pathways in human retinal pigment epithelial (RPE) cells. ARPE-19 cells were treated with different concentrations of LA. Expressions of iNOS and COX-2 were examined using semiquantitative reverse transcription polymerase chain reaction (RT-PCR) and Western blot analysis. Concentrations of nitric oxide (NO) and prostaglandin E(2) (PGE(2)) in the culture medium were determined by enzyme-link immunosorbent assay (ELISA). Activation of p42/44, p38, JNK mitogen-activated protein kinase (MAPK) and nuclear factors (NF)-kappaB were evaluated by Western blot analysis and electrophoretic mobility shift assay (EMSA). We found that LA induced expression of iNOS and COX-2 in RPE cells at the mRNA and protein levels in a time-and dose-dependent manner. Upregulation of iNOS and COX-2 resulted in increased production of NO and PGE(2). Moreover, LA caused degradation of IkappaB and increased NF-kappaB DNA binding activity. Effects of LA-induced iNOS and COX-2 expression were inhibited by a NF-kappaB inhibitor, pyrrolidine dithiocarbamate (PDTC). LA activated p42/44, but not p38 or JNK MAPK. Inhibition of p42/44 activity by PD98059 significantly reduced LA-induced activation of NF-kappaB. Linoleic acid-induced expression of iNOS and COX-2 as well as PGE(2) and NO release in RPE cells were sequentially mediated through activation of p42/p44, MAPK, then NF-kappaB. These results may provide new insights into both mechanisms of LA action on RPE cells and pathogenesis of age-related macular degeneration.
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Affiliation(s)
- I-Mo Fang
- Department of Ophthalmology, National Taiwan University Hospital, No. 7, Chung-Shan S. Rd, Taipei, Taiwan
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153
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Lotery A, Trump D. Progress in defining the molecular biology of age related macular degeneration. Hum Genet 2007; 122:219-36. [PMID: 17659362 DOI: 10.1007/s00439-007-0406-3] [Citation(s) in RCA: 52] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2007] [Accepted: 07/11/2007] [Indexed: 01/15/2023]
Abstract
Age related macular degeneration (AMD) is an extremely prevalent complex genetic disorder. Its incidence rises exponentially in the elderly to a frequency of 1 in 2 in the general population by age 85. It affects approximately 25 million people and is the commonest cause of irreversible visual loss in the Western world. It is therefore a major public health problem. However, until recently its aetiology was unknown. Our understanding of both the molecular biology of AMD and the relevant clinical treatments has progressed dramatically in the last 2 years. Two genes of large effect have been identified which together contribute to over 70% of the population attributable risk of AMD. Treatments which inhibit expression of vascular endothelial growth factor have been developed which can rescue vision in the "wet" form of the disease. The association of complement factor H with AMD highlights the importance of the alternative complement pathway in the development of AMD whilst the pathophysiology of the serine protease HTRA1 is now under intensive study. This review will give an insight into these developments and will summarise our current knowledge of the molecular biology of AMD.
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Affiliation(s)
- Andrew Lotery
- Clinical Neurosciences Division, University of Southampton, Southampton General Hospital, Southampton, SO16 6YD, UK.
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154
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Chiu CJ, Milton RC, Gensler G, Taylor A. Association between dietary glycemic index and age-related macular degeneration in nondiabetic participants in the Age-Related Eye Disease Study. Am J Clin Nutr 2007; 86:180-8. [PMID: 17616779 DOI: 10.1093/ajcn/86.1.180] [Citation(s) in RCA: 61] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
BACKGROUND Age-related macular degeneration (AMD) is the major cause of irreversible blindness. AMD appears to share several carbohydrate-related mechanisms and risk factors with diabetes-related diseases, including retinopathy and cardiovascular disease (CVD); however, to date, only one small study has addressed this issue. OBJECTIVE The objective was to test the hypothesis that dietary glycemic index (dGI), which has been related to the risk of diabetes and CVD, is associated with the risk and severity of AMD in nondiabetic elderly populations. DESIGN Dietary information was obtained from 4099 participants aged 55-80 y (56% women) in the Age-Related Eye Disease Study (AREDS). A total of 8125 eligible eyes at baseline were classified into 1 of 5 AMD groups according to the size and extent of drusen, the presence of geographic atrophy, and neovascular changes. We used a generalized estimating approach to evaluate the relations between dGI and risk and severity of AMD with eyes as the unit of analysis. RESULTS Compared with eyes in the first quintile of dGI, eyes in the fourth and fifth quintiles had a significantly or suggestively higher risk of large drusen, geographic atrophy, and neovascularization. The multivariate-adjusted odds ratios (95% CIs) for the highest quintile were 1.42 (1.09, 1.84), 1.78 (0.81, 3.90), and 1.41 (0.95, 2.08), respectively, of which only the odds ratio for large drusen was significant. A significant positive relation between dGI and severity of AMD was also noted (P for trend < 0.001). There was a 49% increase in the risk of advanced AMD (geographic atrophy plus neovascularization) for persons with a dGI higher than the sex median (women: >or=77.9; men: >or=79.3). This result indicated that 20% of prevalent cases of AMD would have been eliminated if the AREDS participants consumed diets with a dGI below the median. CONCLUSION The association between dGI and AMD from the AREDS cross-sectional analysis at baseline suggests that a reduction in the dGI, a modifiable risk factor, may provide a means of diminishing the risk of AMD.
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Affiliation(s)
- Chung-Jung Chiu
- Jean Mayer US Department of Agriculture, Human Nutrition Research Center on Aging at Tufts University, Boston, MA 02111, USA
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155
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Douglas IJ, Cook C, Chakravarthy U, Hubbard R, Fletcher AE, Smeeth L. A case-control study of drug risk factors for age-related macular degeneration. Ophthalmology 2007; 114:1164-9. [PMID: 17544775 DOI: 10.1016/j.ophtha.2006.09.018] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2006] [Revised: 09/12/2006] [Accepted: 09/26/2006] [Indexed: 10/23/2022] Open
Abstract
OBJECTIVE To investigate the association between age-related macular degeneration (AMD) and exposure to antacids, antithyroids, thyroid hormones, and thiazide diuretics. DESIGN Matched case-control study. PARTICIPANTS Population-based participants were selected from the United Kingdom General Practice Research Database. A total of 18,007 people with diagnosed AMD were compared with 86 169 controls matched for age, gender, and general practice. METHODS Conditional logistic regression was used to determine the association between exposure to each drug group of interest and a diagnosis of AMD, adjusting for relevant confounding variables. MAIN OUTCOME MEASURES The primary outcome was the odds ratio for the association between exposure to antacids, antithyroids, thyroid hormones, or thiazide diuretics and AMD. Secondary analyses were conducted to assess the effect of recent exposure to the drugs of interest, the total number of prescriptions received, and restricting the data set to participants with more than 2 years of observation time. RESULTS The crude odds ratios for association between any record of drug exposure and AMD were as follows: 1.34 (95% confidence interval [CI], 1.29-1.39) for antacids; 1.15 (95% CI, 0.92-1.44) for antithyroids; 1.34 (95% CI, 1.29-1.39) for thyroid hormones; and 1.13 (95% CI, 1.08-1.17) for thiazide diuretics. After adjusting for consultation rate, observation time, diabetes, heart failure, hyperlipidemia, cardiovascular drug use, atherosclerosis, hypertension, aspirin use, hormone replacement therapy use, body mass index, alcohol consumption, and smoking, the odds ratios reduced to: 1.06 (95% CI, 1.02-1.10) for antacids, 0.98 (95% CI, 0.78-1.24) for antithyroids, 0.99 (95% CI, 0.92-1.06) for thyroid hormones, and 0.98 (95% CI, 0.94-1.02) for thiazides. Secondary analyses were consistent with these findings for all 4 drug categories. CONCLUSIONS No association was detected between short- and medium-term use of antithyroids, thyroid hormones, and thiazide diuretics and the risk of AMD. Short- and medium-term use of antacids seems to be associated with a small increase in the risk of this disease. However, this increased risk is likely the result of residual confounding by smoking or uncontrolled confounding resulting from socioeconomic status. No conclusions could be drawn regarding longer-term use of each drug category.
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Affiliation(s)
- Ian J Douglas
- Department of Epidemiology and Population Health, London School of Hygiene and Tropical Medicine, London, United Kingdom
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156
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Tan JSL, Mitchell P, Smith W, Wang JJ. Cardiovascular Risk Factors and the Long-term Incidence of Age-Related Macular Degeneration. Ophthalmology 2007; 114:1143-50. [PMID: 17275090 DOI: 10.1016/j.ophtha.2006.09.033] [Citation(s) in RCA: 154] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2006] [Revised: 09/21/2006] [Accepted: 09/26/2006] [Indexed: 11/25/2022] Open
Abstract
PURPOSE To assess the relationship between cardiovascular disease and cardiovascular risk factors, other than smoking, and risk of long-term incident age-related macular degeneration (AMD). DESIGN Population-based cohort study. PARTICIPANTS There were 3654 baseline (1992-1994) participants aged > or = 49 years included in the Blue Mountains region, west of Sydney, Australia. Of these, 2335 (75% of survivors) were reexamined after 5 years (1997-1999) and 1952 (76% of survivors) after 10 years (2002-2004). METHODS Stereoscopic color fundus photographs were graded using the Wisconsin Age-related Maculopathy Grading System. History, physical examination, and fasting blood samples provided data on possible risk factors. Age-related macular degeneration incidence was calculated using the Kaplan-Meier survival approach. Discrete linear logistic models were used to assess risk of incident AMD. Relative risks (RR) and 95% confidence intervals (CI) are presented after adjusting for age, gender, smoking, and other risk factors. MAIN OUTCOME MEASURE Incident early and late AMD. RESULTS Increasing high-density lipoprotein (HDL) cholesterol was inversely related to incident late AMD (RR per standard deviation [SD] increase, 0.74; 95% CI, 0.56-0.99). Elevated total/HDL cholesterol ratio predicted late AMD (RR per SD increase, 1.35; 95% CI, 1.07-1.70) and geographic atrophy (GA; RR per SD, 1.63; 95% CI, 1.18-2.25). Diabetes predicted incident GA (RR, 3.89; 95% CI, 1.36-11.08), but not neovascular AMD. History of stroke (RR 2.01; 95% CI, 1.12-3.58), or any cardiovascular disease (stroke, myocardial infarction, or angina; RR, 1.57; 95% CI, 1.13-2.16) predicted incident early AMD and incident indistinct soft or reticular drusen (RR, 2.38; 95% CI, 1.33-4.27 for stroke; RR, 1.80; 95% CI, 1.28-2.52 for any cardiovascular disease). Neither pulse pressure, systolic or diastolic blood pressure, or presence of hypertension at baseline were associated with incident AMD. CONCLUSIONS Our findings provide some evidence of links between cardiovascular risk factors and AMD. Further prospective evaluation of these relationships is warranted, as these findings could have therapeutic implications.
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Affiliation(s)
- Jennifer S L Tan
- Centre for Vision Research, Department of Ophthalmology, Westmead Millennium Institute, University of Sydney, Westmead, Australia
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157
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Richer S, Devenport J, Lang JC. LAST II: Differential temporal responses of macular pigment optical density in patients with atrophic age-related macular degeneration to dietary supplementation with xanthophylls. ACTA ACUST UNITED AC 2007; 78:213-9. [PMID: 17478338 DOI: 10.1016/j.optm.2006.10.019] [Citation(s) in RCA: 77] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2006] [Revised: 07/19/2006] [Accepted: 10/20/2006] [Indexed: 11/18/2022]
Abstract
BACKGROUND Age-related macular degeneration (ARMD) is the leading cause of vision loss in aging Western societies. The objective of the Lutein Antioxidant Supplementation Trial (LAST) was to determine whether specific dietary interventions increased macular pigment optical density (MPOD) and visual function in patients with atrophic ARMD. The current objective of LAST II is to discern those specific characteristics that increase MPOD, i.e., that might differentiate a responder from a nonresponder. METHODS The LAST study was a prospective, 12-month, randomized, double-masked, placebo-controlled trial conducted at an urban midwestern Veterans Administation Hospital from August 1999 to May 2001. Ninety patients with atrophic ARMD entered the study and were assigned randomly to 1 of 3 groups. Patients in group 1 received 10 mg lutein; in group 2, 10 mg lutein in combination with vitamins, minerals, and antioxidants; and in group 3, maltodextrin placebo. Changes in macular MPOD over time were evaluated. Characteristics potentially influencing MPOD included age, weight (body mass index), initial baseline values of macular pigment, and combining xanthophylls with other nutrients. RESULTS MPOD increased with supplementation and declined slightly without supplementation (regression slopes not equal to zero in supplemented groups, P < 0.02). The highest increases in MPOD over time occurred in patients with lower baseline values of MPOD. Statistically significant increases in MPOD density were observed in the lutein group for patients with baseline MPOD <or=0.3 optical density units and up to 0.2 optical density units in the lutein plus antioxidant group. Further analysis found that none of the subjects' eyes in the lowest quartile of baseline MPOD were in the lowest quartile for change in MPOD. CONCLUSION Noteworthy is the observation that those individuals with lowest MPOD, and in greatest need of supplementation, were also most likely to benefit from either the lutein or the lutein plus antioxidant supplementation. For those individuals who responded to supplementation, their macular pigment optical density had not ceased to increase at 12 months' duration of supplementation. The inference is that if a deficiency in macular pigment optical density is accurately diagnosed, effective interventions should be able to re-establish this prophylactic barrier.
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Affiliation(s)
- Stuart Richer
- Department of Veterans Affairs, Medical Center Eye Clinic, North Chicago, Illinois 60064-3095, USA.
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158
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Malek G, Mace B, Saloupis P, Schmechel D, Rickman D, Sullivan P, Rickman CB. Initial observations of key features of age-related macular degeneration in APOE targeted replacement mice. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2007; 572:109-17. [PMID: 17249563 DOI: 10.1007/0-387-32442-9_17] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/13/2023]
Affiliation(s)
- Goldis Malek
- Department of Ophthalmology, Duke University Medical Center, Durham, North Carolina 27710, USA
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159
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Abstract
The retinal pigment epithelium (RPE) maintains retinal function as the metabolic gatekeeper between photoreceptors (PRs) and the choriocapillaries. The RPE and Bruch's membrane (BM) suffer cumulative damage over lifetime, which is thought to induce age-related macular degeneration (AMD) in susceptible individuals. Unlike palliative pharmacologic treatments, replacement of the RPE has a curative potential for AMD. This article reviews mechanisms leading to RPE dysfunction in aging and AMD, laboratory studies on RPE transplantation, and surgical techniques used in AMD patients. Future strategies using ex vivo steps prior to transplantation, BM prosthetics, and stem cell applications are discussed. The functional peculiarity of the macular region, epigenetic phenomena leading to an age-related shift in protein expression, along with the accumulation of lipofuscin may affect the metabolism in the central RPE. Thickening of BM with age decreases its hydraulic conductivity. Drusen are deposits of extracellular material and formed in part by activation of the alternative complement pathway in individuals carrying a mutant allele of complement factor H. AMD likely represents an umbrella term for a disease entity with multifactorial etiology and manifestations. Presently, a slow progressing (dry) non-neovascular atrophic form and a rapidly blinding neovascular (wet) form are discerned. No therapy is currently available for the former, while RPE transplantation and promising (albeit non-causal) anti-angiogenic therapies are available for the latter. The potential of RPE transplantation was demonstrated in animal models. Rejection of allogeneic homologous transplants in patients focused further studies on autologous sources. In vitro studies elucidated cell adhesion and wound healing mechanisms on aged human BM. Currently, autologous RPE, harvested from the midperiphery, is being transplanted as a cell suspension or a patch of RPE and choroid in AMD patients. These techniques have been evaluated from several groups. Autologous RPE transplants may have the disadvantage of carrying the same genetic information that may have led to AMD manifestation. An intermittent culturing step would allow for in vitro therapy of the RPE, its rejuvenation and prosthesis of BM to improve the success RPE transplants. Recent advances in stem cell biology when combined with lessons learned from studies of RPE transplantation are intriguing future therapeutic modalities for AMD patients.
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Affiliation(s)
- Susanne Binder
- Department of Ophthalmology, Rudolf Foundation Clinic, Hospital of the City of Vienna, Vienna, Austria.
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160
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Delcourt C, Carrière I, Cristol JP, Lacroux A, Gerber M. Dietary fat and the risk of age-related maculopathy: the POLANUT study. Eur J Clin Nutr 2007; 61:1341-4. [PMID: 17299457 DOI: 10.1038/sj.ejcn.1602685] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
This study aimed at assessing the associations of dietary fat with the risk of age-related maculopathy (ARM), in the framework of a population-based study from southern France. Nutritional data were collected using a dietitian-administered food-frequency questionnaire. ARM was classified from retinal photographs using the international classification and included neovascular age-related macular degeneration, geographic atrophy, soft indistinct drusen, soft distinct drusen associated with pigmentary abnormalities. After multivariate adjustment, high total, saturated and monounsaturated fat intake were associated with increased risk for ARM (odds ratio (OR)=4.74, P=0.007; OR=2.70, P=0.04; and OR= 3.50, P=0.03, respectively). Total polyunsaturated fatty acid was not significantly associated with ARM. Total and white fish intake was not significantly associated with ARM, but fatty fish intake (more than once a month versus less than once a month) was associated with a 60% reduction in risk for ARM (OR=0.42, P=0.01).
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Affiliation(s)
- C Delcourt
- Inserm, Research Unit U593 for Epidemiology, Public Health and Development, Bordeaux, France.
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161
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Metzner C, Lüder W. [Plant omega 3- and omega 6-fatty acids]. PHARMAZIE IN UNSERER ZEIT 2007; 36:134-41. [PMID: 17424999 DOI: 10.1002/pauz.200600212] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/14/2023]
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162
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Seddon JM. Multivitamin-multimineral supplements and eye disease: age-related macular degeneration and cataract. Am J Clin Nutr 2007; 85:304S-307S. [PMID: 17209215 DOI: 10.1093/ajcn/85.1.304s] [Citation(s) in RCA: 49] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023] Open
Abstract
The prevalence and effects of age-related macular degeneration (AMD) and cataract are increasing dramatically as the proportion of elderly in our population continues to rise. A multivitamin-multimineral supplement with a combination of vitamin C, vitamin E, beta-carotene, and zinc (with cupric oxide) is recommended for AMD but not cataract. Weak support exists for multivitamins or other vitamin supplements from observational studies of cataract. The results of observational studies suggest that a healthy lifestyle with a diet containing foods rich in antioxidants, particularly lutein and zeaxanthin, as well as n-3 fatty acids, appears beneficial for AMD and possibly cataract. The Age-Related Eye Disease Study II will evaluate some of these additional nutrients as dietary supplements in a randomized trial.
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Affiliation(s)
- Johanna M Seddon
- Epidemiology Unit, Massachusetts Eye and Ear Infirmary, Harvard Medical School, Boston, MA 02114, USA.
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163
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Wang JJ. Genetic and modifiable risk factors for age-related macular degeneration. EXPERT REVIEW OF OPHTHALMOLOGY 2006. [DOI: 10.1586/17469899.1.2.181] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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164
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Abstract
Dietary trans FA at sufficiently high levels have been found to increase low density lipoprotein (LDL)-cholesterol and decrease high density lipoprotein (HDL)-cholesterol (and thus to increase the ratio of LDL-cholesterol/HDL-cholesterol) compared with diets high in cis monounsaturated FA or PUFA. The dietary levels of trans FA at which these effects are easily measured are around 4% of energy or higher to increase LDL-cholesterol and around 5 to 6% of energy or higher to decrease HDL-cholesterol, compared with essentially trans-free control diets. Very limited data at lower levels of intake (less than 4% of energy) are available. Most health professional organizations and some governments now recommend reduced consumption of foods containing trans FA, and effective January 1, 2006, the U.S. Food and Drug Administration requires the labeling of the amounts of trans FA per serving in packaged foods. In response, the food industry is working on ways to eliminate or greatly reduce trans FA in food products. Current efforts focus on four technological options: (i) modification of the hydrogenation process, (ii) use of interesterification, (iii) use of fractions high in solids from natural oils, and (iv) use of trait-enhanced oils. Challenges to the food industry in replacing trans FA in foods are to develop formulation options that provide equivalent functionality, are economically feasible, and do not greatly increase saturated FA content.
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Affiliation(s)
- J Edward Hunter
- Department of Chemistry, University of Cincinnati, Cincinnati, Ohio 45221-0172, USA.
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165
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Wang JJ, Flood V, Mitchell P. Facts on fats: what are the implications? Clin Exp Ophthalmol 2006; 34:393-4. [PMID: 16872331 DOI: 10.1111/j.1442-9071.2006.01267.x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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166
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Abstract
Cardiovascular disease and age-related macular degeneration (AMD) may share common risk factors in their causal pathways. Decades of research from the cardiovascular sciences on fats have led investigators to focus on specific types of fats rather than total fat as a whole. They have established that saturated and trans-unsaturated fats (trans fats) are damaging to cardiovascular health while polyunsaturated fats, particularly the marine omega 3 fatty acids appear protective. This has led to a number of studies investigating the associations of fat and AMD. Though the causal relationship between fats and AMD remain unproven, some studies suggest that an association may be present. To be able to understand and interpret the study results and their implications, an understanding of the fats in the diet is important. This review aims to give an overview of fatty acids, particularly the trans-unsaturated fatty acids, and the relevant food groups.
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Affiliation(s)
- Elaine W-T Chong
- Centre for Eye Research Australia, The University of Melbourne, Melbourne, Victoria, Australia.
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167
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Hodge WG, Schachter HM, Barnes D, Pan Y, Lowcock EC, Zhang L, Sampson M, Morrison A, Tran K, Miguelez M, Lewin G. Efficacy of ω-3 Fatty Acids in Preventing Age-Related Macular Degeneration. Ophthalmology 2006; 113:1165-72; quiz 1172-3, 1178. [PMID: 16815401 DOI: 10.1016/j.ophtha.2006.02.043] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2005] [Revised: 02/14/2006] [Accepted: 02/14/2006] [Indexed: 10/24/2022] Open
Abstract
TOPIC What is the evidence for efficacy of dietary and/or supplemental omega-3 fatty acids in preventing age-related macular degeneration (AMD)? CLINICAL RELEVANCE Age-related macular degeneraion is the leading cause of blindness and vision impairment in persons older than 50 years living in North America. There is no cure for AMD, and treatment does not usually restore vision but only prevents disease progression to a modest degree. omega-3 fatty acids are considered potentially important antioxidants and are being considered as an arm of the Age-Related Eye Disease Study II clinical trial. METHODS/LITERATURE REVIEWED Keywords were searched in Medline, Pre-Medline, Embase, and the Cochrane Library on Ovid. There was no restriction on the year or language of publication. RESULTS There were 6 observational studies found, but the specific outcomes, exposures, and covariates studied all varied greatly. CONCLUSION There is some clinical evidence for protection of AMD from omega-3 fatty acids. However, the results are not consistent. Hence, our conclusion is that this issue is neither clearly supported nor refuted by the present world literature. This is an intriguing and extremely important question but needs further study first with prospective cohort designs and, if positive, randomized clinical trials.
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Affiliation(s)
- William G Hodge
- Department of Ophthalmology, University of Ottawa Eye Institute, Ottawa, Canada.
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168
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Haddad S, Chen CA, Santangelo SL, Seddon JM. The Genetics of Age-Related Macular Degeneration: A Review of Progress to Date. Surv Ophthalmol 2006; 51:316-63. [PMID: 16818082 DOI: 10.1016/j.survophthal.2006.05.001] [Citation(s) in RCA: 225] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
Age-related macular degeneration (AMD) is the leading cause of vision loss and blindness among older adults in the USA and throughout the developed world. Etiological research suggests that AMD is a complex disease, caused by the actions and interactions of multiple genes and environmental factors. Familial aggregation studies, twin studies, and segregation analyses have provided strong evidence for the heritability of AMD, and linkage and association studies have been conducted to localize the disease-causing genes. Whole genome linkage scans have implicated nearly every chromosome in the human genome, with the most replicated signals residing on 1q25-31 and 10q26. Association studies have identified a major risk variant within the complement factor H gene (CFH), and recent reports suggest that PLEKHA1/LOC387715 and the BF/C2 regions may be major risk loci for AMD as well. Several other genes have had at least one positive association finding and deserve further exploration. Among these, apolipoprotein E (APOE) may be a minor risk locus. Additional genes will likely be identified, and future studies should explore the potential interactions of these genes with other genes as well as environmental factors.
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Affiliation(s)
- Stephen Haddad
- Psychiatric and Neurodevelopmental Genetics Unit, Massachusetts General Hospital, Boston, 02114, USA
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169
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Johnson EJ, Schaefer EJ. Potential role of dietary n-3 fatty acids in the prevention of dementia and macular degeneration. Am J Clin Nutr 2006; 83:1494S-1498S. [PMID: 16841859 DOI: 10.1093/ajcn/83.6.1494s] [Citation(s) in RCA: 69] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Dementia and age-related macular degeneration (AMD) are major causes of disability in the elderly. n-3 Fatty acids, particularly docosahexaenoic acid (DHA), are highly concentrated in brain and retinal tissue and may prevent or delay the progression of dementia and AMD. Low dietary intakes and plasma concentrations have been reported to be associated with dementia, cognitive decline, and AMD risk. The major dietary sources of DHA are fish and fish oils, although dietary supplements are available. At this point, it is not possible to make firm recommendations regarding n-3 fatty acids and the prevention of dementia and AMD. Our own unpublished observations from the Framingham Heart Study suggest that > or =180 mg/d of dietary DHA (approximately 2.7 fish servings/wk) is associated with an approximately 50% reduction in dementia risk. At least this amount of DHA is generally found in one commercially available 1-g fish oil capsule given daily.
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Affiliation(s)
- Elizabeth J Johnson
- Carotenoid & Health and Lipid Metabolism Laboratories, Jean Mayer U.S. Department of Agriculture Human Nutrition Research Center on Aging at Tufts University, Boston, MA 02111, USA.
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170
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Guymer RH, Chong EWT. Modifiable risk factors for age‐related macular degeneration. Med J Aust 2006; 184:455-8. [PMID: 16646746 DOI: 10.5694/j.1326-5377.2006.tb00318.x] [Citation(s) in RCA: 51] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2005] [Accepted: 03/07/2006] [Indexed: 11/17/2022]
Abstract
Age-related macular degeneration (AMD) is the leading cause of irreversible blindness in Australia and other Western countries. As there is no cure for AMD, and treatments to stop its progression have met with limited success, there is an interest in identifying modifiable risk factors to prevent or slow disease progression. To date, smoking is the only proven modifiable risk factor for AMD. Other factors under study include (i) cardiovascular risk factors such as hypertension, body mass index, and atherosclerosis; and (ii) dietary risk factors including fat and antioxidant intake, but so far these studies have produced conflicting results. Dietary fat in relation to AMD has recently attracted media attention. Despite very limited work supporting an association between vegetable fat and AMD, widespread publicity advocating margarine as a cause of AMD and encouraging use of butter instead has caused confusion and anxiety among sufferers of AMD and the general public, as well as concern among health professionals. The antioxidant carotenoids--lutein and zeaxanthin--found in dark green or yellow vegetables exist in high concentrations in the macula and are hypothesised to play a protective role. Of nine controlled trials of supplementation with carotenoids and other antioxidants, three suggested that various combinations of antioxidants and carotenoids were protective. While a low-fat diet rich in dark green and yellow vegetables is advocated in general, any specific recommendations regarding certain fats or antioxidant supplementation and AMD are not based on consistent findings at this stage.
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Affiliation(s)
- Robyn H Guymer
- Department of Ophthalmology, Centre for Eye Research Australia, University of Melbourne, Melbourne, VIC, Australia
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171
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Chiu CJ, Hubbard LD, Armstrong J, Rogers G, Jacques PF, Chylack LT, Hankinson SE, Willett WC, Taylor A. Dietary glycemic index and carbohydrate in relation to early age-related macular degeneration. Am J Clin Nutr 2006; 83:880-6. [PMID: 16600942 DOI: 10.1093/ajcn/83.4.880] [Citation(s) in RCA: 50] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023] Open
Abstract
BACKGROUND Several dietary factors have been linked to age-related maculopathy (ARM), the early form of age-related macular degeneration, and there is reason to think that dietary carbohydrate may play a role in the development of ARM. OBJECTIVE The purpose of the present study was to examine the relation between dietary carbohydrate quality, as measured by dietary glycemic index (GI) or total carbohydrate intake, and ARM. DESIGN From the Nurses' Health Study, 1036 eyes from 526 Boston-area participants without a previous ARM diagnosis were included in the present study. The presence and degree of ARM were classified by the Age-Related Eye Diseases Study system. Long-term dietary information was based on data from an average of 4 food-frequency questionnaires collected over a 10-y period before the assessment of ARM. With eyes as the unit of analysis, we used a generalized estimating approach to logistic regression to estimate the odds ratios for ARM in a manner that accounted for the lack of independence between the 2 eyes from the same subject. RESULTS After multivariate adjustment, dietary GI was related to ARM (specifically to retinal pigmentary abnormalities), whereas total carbohydrate intake was not. The odds ratio for ARM being in the highest tertile of dietary GI (> or =77.0) versus the lowest (<74.6) was 2.71 (95% CI: 1.24, 5.93; P for trend = 0.01). Neither dietary GI nor total carbohydrate intake was related to drusen. CONCLUSION Our results suggest that dietary GI may be an independent risk factor for ARM.
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Affiliation(s)
- Chung-Jung Chiu
- Jean Mayer US Department of Agriculture Human Nutrition Research Center on Aging at Tufts University, 711 Washington Street, Boston, MA 02111, USA
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Leung IYF, Sandstrom MM, Zucker CL, Neuringer M, Max Snodderly D. Nutritional manipulation of primate retinas. IV. Effects of n--3 fatty acids, lutein, and zeaxanthin on S-cones and rods in the foveal region. Exp Eye Res 2006; 81:513-29. [PMID: 15916761 DOI: 10.1016/j.exer.2005.03.009] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2004] [Revised: 02/28/2005] [Accepted: 03/21/2005] [Indexed: 11/25/2022]
Abstract
Lutein and zeaxanthin are xanthophylls selectively accumulated by primate retinas that may protect the macula from age-related macular degeneration. In this project, we manipulated n-3 fatty acids, lutein and/or zeaxanthin levels in the diet and studied their possible outcome on S-cone and rod cell density in the foveal region. Rhesus monkeys (7-16 year, n=17) were fed from birth xanthophyll-free semipurified diets with either adequate or low n-3 fatty acids. Five monkeys were supplemented with lutein and six with zeaxanthin for 6-24 months, while six remained xanthophyll-free until sacrifice. Retinas were embedded in methacrylate and serial 2 microm sections were cut along the vertical meridian. Rod nuclei, and immuno-labelled outer segments of S-cones and rods, were reconstructed and counted in an 8 microm strip. The density profiles were compared with data from control monkeys (n=7) fed a standard laboratory diet. S-cone density profiles were symmetrical along the vertical meridian and the densities decreased rapidly with retinal eccentricity. Rod densities were higher in the superior region than the inferior region in most of the control and experimental animals. Unlike the significant effects observed for retinal pigment epithelial cells of these same monkeys (Leung, I.Y-F., Sandstrom, M.M., Zucker, C.L., Neuringer, M., Snodderly, D.M., 2004. Nutritional manipulation of primate retinas. II. Effects of age, n-3 fatty acids, lutein, and zeaxanthin on retinal pigment epithelium. Invest. Ophthalmol. Vis. Sci. 45, 3244-3256), neither xanthophyll supplementation nor low dietary n-3 fatty acids produced consistent effects on S-cone or rod density profiles of the experimental animals. However, monkeys low in n-3 fatty acids had increased variability of S-cone density in the fovea and low density of foveal rod outer segments. The high variability suggests that the photoreceptors of some animals were resistant to the nutritional manipulations, while others may have been affected. Thus, the photoreceptors appear less sensitive than the retinal pigment epithelium to these nutritional manipulations. However, it is possible that more consistent effects would emerge at a later age or after exposure to stressors such as high light levels.
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Affiliation(s)
- Ivan Y-F Leung
- The Schepens Eye Research Institute, 20 Staniford Street, Boston, MA 02114, USA.
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173
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Epidemiology of Age-Related Macular Degeneration. Retina 2006. [DOI: 10.1016/b978-0-323-02598-0.50064-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/07/2023]
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Lu M, Cho E, Taylor A, Hankinson SE, Willett WC, Jacques PF. Prospective study of dietary fat and risk of cataract extraction among US women. Am J Epidemiol 2005; 161:948-59. [PMID: 15870159 DOI: 10.1093/aje/kwi118] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
The authors examined prospectively the association between dietary fat intake and cataract extraction in adult women from the Nurses' Health Study. A total of 71,083 women were followed prospectively for up to 16 years between 1984 and 2000. Dietary fat was assessed by repeated food frequency questionnaires. Incident cases of cataract extraction were determined by a biennial questionnaire. The multivariate-adjusted relative risk for the highest compared with the lowest quintile of total fat intake was 1.10 (95% confidence interval (CI): 0.99, 1.22; p(trend) = 0.01). Women in the highest quintile of long-chain omega-3 fatty acid had a 12% lower risk of cataract extraction compared with those in the lowest quintile (relative risk = 0.88, 95% CI: 0.79, 0.98; p(trend) = 0.02). Total fish intake was inversely associated with cataract (for intake of > or = 3/week vs. <1/month: relative risk = 0.89, 95% CI: 0.81, 0.98; p(trend) = 0.01). The authors' findings suggest that higher intake of long-chain omega-3 fatty acid (eicosapentaenoic acid and docosahexaenoic acid) and consumption of fish may modestly reduce the risk of cataract.
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Affiliation(s)
- Minyi Lu
- Nutritional Epidemiology Program, Jean Mayer US Department of Agriculture Human Nutrition Research Center on Aging at Tufts University, Boston, MA 02111, USA
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175
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Lu M, Taylor A, Chylack LT, Rogers G, Hankinson SE, Willett WC, Jacques PF. Dietary fat intake and early age-related lens opacities. Am J Clin Nutr 2005; 81:773-9. [PMID: 15817851 DOI: 10.1093/ajcn/81.4.773] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
BACKGROUND Dietary fat may affect lens cell membrane composition and function, which are related to age-related cataract. OBJECTIVE The objective of the study was to examine the association between long-term dietary fat intake and the prevalence of age-related nuclear, cortical, and posterior subcapsular lens opacities. DESIGN Women (n = 440) aged 53-73 y from the Boston area without previously diagnosed cancer, diabetes, or cataract were selected from the Nurses' Health Study cohort. Intakes of total fat and selected fatty acids were calculated as the average of intake data from 5 food-frequency questionnaires collected between 1980 and the study eye examination (1993-1995). Nuclear opacity was defined as grade >/=2.5, cortical opacity as grade >/=1.0, and posterior subcapsular opacity as grade >/=0.5 according to the Lens Opacities Classification System III. RESULTS There were significant positive associations between linoleic and linolenic acid intakes and the prevalence of nuclear opacity. The odds ratios for nuclear opacity in women with intakes in the highest quartile and women with intakes in the lowest quartile were 2.2 (95% CI: 1.1, 4.6; P for trend = 0.02) for linoleic acid and 2.2 (95% CI: 1.1, 4.5; P for trend = 0.05) for linolenic acid. There were no significant associations between intakes of any type of fat and either cortical or posterior subscapular opacity. CONCLUSIONS High intake of the 18-carbon polyunsaturated fatty acids linoleic acid and linolenic acid may increase the risk of age-related nuclear opacity. Further study is needed to clarify the relation between dietary fat and cataract risk.
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Affiliation(s)
- Minyi Lu
- Nutritional Epidemiology Program and the Center for Ophthalmic Research, Department of Ophthalmology, Harvard Medical School and Brigham and Women's Hospital, Boston, MA, USA
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SanGiovanni JP, Chew EY. The role of omega-3 long-chain polyunsaturated fatty acids in health and disease of the retina. Prog Retin Eye Res 2005; 24:87-138. [PMID: 15555528 DOI: 10.1016/j.preteyeres.2004.06.002] [Citation(s) in RCA: 498] [Impact Index Per Article: 26.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
In this work we advance the hypothesis that omega-3 (omega-3) long-chain polyunsaturated fatty acids (LCPUFAs) exhibit cytoprotective and cytotherapeutic actions contributing to a number of anti-angiogenic and neuroprotective mechanisms within the retina. omega-3 LCPUFAs may modulate metabolic processes and attenuate effects of environmental exposures that activate molecules implicated in pathogenesis of vasoproliferative and neurodegenerative retinal diseases. These processes and exposures include ischemia, chronic light exposure, oxidative stress, inflammation, cellular signaling mechanisms, and aging. A number of bioactive molecules within the retina affect, and are effected by such conditions. These molecules operate within complex systems and include compounds classified as eicosanoids, angiogenic factors, matrix metalloproteinases, reactive oxygen species, cyclic nucleotides, neurotransmitters and neuromodulators, pro-inflammatory and immunoregulatory cytokines, and inflammatory phospholipids. We discuss the relationship of LCPUFAs with these bioactivators and bioactive compounds in the context of three blinding retinal diseases of public health significance that exhibit both vascular and neural pathology. How is omega-3 LCPUFA status related to retinal structure and function? Docosahexaenoic acid (DHA), a major dietary omega-3 LCPUFA, is also a major structural lipid of retinal photoreceptor outer segment membranes. Biophysical and biochemical properties of DHA may affect photoreceptor membrane function by altering permeability, fluidity, thickness, and lipid phase properties. Tissue DHA status affects retinal cell signaling mechanisms involved in phototransduction. DHA may operate in signaling cascades to enhance activation of membrane-bound retinal proteins and may also be involved in rhodopsin regeneration. Tissue DHA insufficiency is associated with alterations in retinal function. Visual processing deficits have been ameliorated with DHA supplementation in some cases. What evidence exists to suggest that LCPUFAs modulate factors and processes implicated in diseases of the vascular and neural retina? Tissue status of LCPUFAs is modifiable by and dependent upon dietary intake. Certain LCPUFAs are selectively accreted and efficiently conserved within the neural retina. On the most basic level, omega-3 LCPUFAs influence retinal cell gene expression, cellular differentiation, and cellular survival. DHA activates a number of nuclear hormone receptors that operate as transcription factors for molecules that modulate reduction-oxidation-sensitive and proinflammatory genes; these include the peroxisome proliferator-activated receptor-alpha (PPAR-alpha) and the retinoid X receptor. In the case of PPAR-alpha, this action is thought to prevent endothelial cell dysfunction and vascular remodeling through inhibition of: vascular smooth muscle cell proliferation, inducible nitric oxide synthase production, interleukin-1 induced cyclooxygenase (COX)-2 production, and thrombin-induced endothelin 1 production. Research on model systems demonstrates that omega-3 LCPUFAs also have the capacity to affect production and activation of angiogenic growth factors, arachidonic acid (AA)-based vasoregulatory eicosanoids, and MMPs. Eicosapentaenoic acid (EPA), a substrate for DHA, is the parent fatty acid for a family of eicosanoids that have the potential to affect AA-derived eicosanoids implicated in abnormal retinal neovascularization, vascular permeability, and inflammation. EPA depresses vascular endothelial growth factor (VEGF)-specific tyrosine kinase receptor activation and expression. VEGF plays an essential role in induction of: endothelial cell migration and proliferation, microvascular permeability, endothelial cell release of metalloproteinases and interstitial collagenases, and endothelial cell tube formation. The mechanism of VEGF receptor down-regulation is believed to occur at the tyrosine kinase nuclear factor-kappa B (NFkappaB). NFkappaB is a nuclear transcription factor that up-regulates COX-2 expression, intracellular adhesion molecule, thrombin, and nitric oxide synthase. All four factors are associated with vascular instability. COX-2 drives conversion of AA to a number angiogenic and proinflammatory eicosanoids. Our general conclusion is that there is consistent evidence to suggest that omega-3 LCPUFAs may act in a protective role against ischemia-, light-, oxygen-, inflammatory-, and age-associated pathology of the vascular and neural retina.
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Affiliation(s)
- John Paul SanGiovanni
- Division of Epidemiology and Clinical Research, National Eye Insitute, National Institutes of Health, 31 Center Drive, Building 31, Room 6A52, MSC 2510, Bethesda, MD 20892-2510, USA.
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177
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Constable IJ. Age-related macular degeneration and its possible prevention. Med J Aust 2004; 181:471-2. [PMID: 15516188 DOI: 10.5694/j.1326-5377.2004.tb06401.x] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2004] [Accepted: 09/07/2004] [Indexed: 11/17/2022]
Abstract
Despite well publicised claims of the therapeutic value of dietary supplements and other new treatments, the evidence for their effectiveness is modest.
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Hooper L, Thompson RL, Harrison RA, Summerbell CD, Moore H, Worthington HV, Durrington PN, Ness AR, Capps NE, Davey Smith G, Riemersma RA, Ebrahim SBJ. Omega 3 fatty acids for prevention and treatment of cardiovascular disease. Cochrane Database Syst Rev 2004:CD003177. [PMID: 15495044 PMCID: PMC4170890 DOI: 10.1002/14651858.cd003177.pub2] [Citation(s) in RCA: 120] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
BACKGROUND It has been suggested that omega 3 (W3, n-3 or omega-3) fats from oily fish and plants are beneficial to health. OBJECTIVES To assess whether dietary or supplemental omega 3 fatty acids alter total mortality, cardiovascular events or cancers using both RCT and cohort studies. SEARCH STRATEGY Five databases including CENTRAL, MEDLINE and EMBASE were searched to February 2002. No language restrictions were applied. Bibliographies were checked and authors contacted. SELECTION CRITERIA RCTs were included where omega 3 intake or advice was randomly allocated and unconfounded, and study duration was at least six months. Cohorts were included where a cohort was followed up for at least six months and omega 3 intake estimated. DATA COLLECTION AND ANALYSIS Studies were assessed for inclusion, data extracted and quality assessed independently in duplicate. Random effects meta-analysis was performed separately for RCT and cohort data. MAIN RESULTS Forty eight randomised controlled trials (36,913 participants) and 41 cohort analyses were included. Pooled trial results did not show a reduction in the risk of total mortality or combined cardiovascular events in those taking additional omega 3 fats (with significant statistical heterogeneity). Sensitivity analysis, retaining only studies at low risk of bias, reduced heterogeneity and again suggested no significant effect of omega 3 fats. Restricting analysis to trials increasing fish-based omega 3 fats, or those increasing short chain omega 3s, did not suggest significant effects on mortality or cardiovascular events in either group. Subgroup analysis by dietary advice or supplementation, baseline risk of CVD or omega 3 dose suggested no clear effects of these factors on primary outcomes. Neither RCTs nor cohorts suggested increased relative risk of cancers with higher omega 3 intake but estimates were imprecise so a clinically important effect could not be excluded. REVIEWERS' CONCLUSIONS It is not clear that dietary or supplemental omega 3 fats alter total mortality, combined cardiovascular events or cancers in people with, or at high risk of, cardiovascular disease or in the general population. There is no evidence we should advise people to stop taking rich sources of omega 3 fats, but further high quality trials are needed to confirm suggestions of a protective effect of omega 3 fats on cardiovascular health. There is no clear evidence that omega 3 fats differ in effectiveness according to fish or plant sources, dietary or supplemental sources, dose or presence of placebo.
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Affiliation(s)
- L Hooper
- MANDEC, University Dental Hospital of Manchester, Higher Cambridge Street, Manchester, UK, M15 6FH.
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Affiliation(s)
- Suzen M Moeller
- Department of Nutritional Sciences, University of Wisconsin-Madison, 53726-2336, USA
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182
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Seddon JM, Cote J, Rosner B. Progression of age-related macular degeneration: association with dietary fat, transunsaturated fat, nuts, and fish intake. ACTA ACUST UNITED AC 2004; 121:1728-37. [PMID: 14662593 PMCID: PMC8443211 DOI: 10.1001/archopht.121.12.1728] [Citation(s) in RCA: 232] [Impact Index Per Article: 11.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
BACKGROUND Individuals with early or intermediate stages of age-related macular degeneration (AMD) make up a large, growing segment of the elderly population. Evidence is sparse regarding modifiable factors that may decrease the risk of progression to the advanced forms of AMD. OBJECTIVE To advise patients with a high risk for advanced forms of AMD about preventive measures through our evaluation of the relationship between dietary fat intake and the progression of early or intermediate AMD to the advanced stages of the disease associated with visual loss. DESIGN A prospective cohort study with an average follow-up time of 4.6 years. SETTING A hospital-based clinical retinal practice specializing in macular degeneration. Patients The 261 participants were aged 60 years and older and had some sign of nonexudative AMD and visual acuity of 20/200 or better in at least 1 eye. Main Outcome Measure Progression to advanced AMD, which was defined as having geographic atrophy or neovascular disease. RESULTS Higher total fat intake increased the risk of progression to the advanced forms of AMD, with a relative risk (RR) of 2.90 (95% confidence interval, 1.15-7.32) for the highest fat-intake quartile relative to the lowest fat-intake quartile, after controlling for other factors (P trend =.01). Animal fat intake was associated with a 2-fold increased risk of progression (RR, 2.29 for the highest quartile compared with the lowest quartile; 95% confidence interval, 0.91-5.72), although the trend for increasing risk with higher animal fat intake was not significant (P=.09). Higher vegetable fat intake had a stronger relationship with increased risk of AMD progression with an RR of 3.82 (95% confidence interval, 1.58-9.28) for the highest quartile compared with the lowest quartile (P trend =.003). Saturated, monounsaturated, polyunsaturated, and transunsaturated fats increased the likelihood of progression (RR, 2.09 and P trend =.08; RR, 2.21 and P trend =.04; RR, 2.28 and P trend =.04; RR, 2.39 and P trend =.008, respectively). Higher fish intake was associated with a lower risk of AMD progression among subjects with lower linoleic acid intake. Processed baked goods, which are higher in some of these fats, increased the rate of AMD progression approximately 2-fold, and nuts were protective. CONCLUSIONS Among individuals with the early or intermediate stages of AMD, total and specific types of fat intake, as well as some fat-containing food groups, modified the risk of progression to advanced AMD. Fish intake and nuts reduced risk. Since advanced AMD is associated with visual loss and reduced quality of life, these preventive measures deserve additional research and greater emphasis.
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Affiliation(s)
- Johanna M Seddon
- Massachusetts Eye and Ear Infirmary, Epidemiology Unit, Harvard School of Public Health, Boston, Massachesetts 02114, USA.
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183
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Affiliation(s)
- Johanna M Seddon
- Epidemiology Unit, Massachusetts Eye and Ear Infirmary, Boston 02114, USA
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184
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Spaide RF, Armstrong D, Browne R. CHOROIDAL NEOVASCULARIZATION IN AGE-RELATED MACULAR DEGENERATION—WHAT IS THE CAUSE? Retina 2003; 23:595-614. [PMID: 14574243 DOI: 10.1097/00006982-200310000-00001] [Citation(s) in RCA: 86] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Affiliation(s)
- Richard F Spaide
- Vitreous Retina Macula Consultants, New York, New York 10021, USA.
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185
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Seddon JM, Santangelo SL, Book K, Chong S, Cote J. A genomewide scan for age-related macular degeneration provides evidence for linkage to several chromosomal regions. Am J Hum Genet 2003; 73:780-90. [PMID: 12945014 PMCID: PMC1180601 DOI: 10.1086/378505] [Citation(s) in RCA: 165] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2003] [Accepted: 07/08/2003] [Indexed: 11/04/2022] Open
Abstract
We report the results of a genomewide scan for age-related macular degeneration (AMD) in 158 multiplex families. AMD classification was based on fundus photography and was assigned a grade ranging from 1 (no disease) to 5 (exudative disease). Genotyping was performed by the National Heart, Lung, and Blood Institute Mammalian Genotyping Service at Marshfield (404 short tandem repeat markers). The sample included 158 families with two or more siblings with AMD, 490 affected individuals, 101 unaffected individuals, and 38 whose affection status was unknown. Relative pairs included 511 affected sibling, 28 avuncular, 53 cousin, 7 grandparent-grandchild, and 9 grand-avuncular pairs. Two-point parametric and multipoint parametric and nonparametric analyses were performed. Maximum two-point LOD scores of 1.0-2.0 were found for markers on chromosomes 1, 2, 8, 10, 14, 15, and 22. Multipoint analyses were consistent with the two-point results for chromosomes 1, 2, 8, 10, and 22 and provided evidence for additional linkage regions on chromosomes 3, 6, 8, 12, 16, and X. Our signals on chromosomes 1q, 6p, and 10q are consistent with some other previously published results. Significant linkage to AMD was found for one marker on chromosome 2, two adjacent markers on chromosome 3, two adjacent markers on chromosome 6, and seven contiguous markers on chromosome 8, with empirical P values of .00001. The consistency of many of the other signals across both two-point and multipoint, as well as parametric and nonparametric, analyses indicate several other regions worthy of follow-up.
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Affiliation(s)
- Johanna M Seddon
- Ophthalmology/Epidemiology Unit, Massachusetts Eye and Ear Infirmary, Harvard Medical School, Boston, MA 02114, USA.
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Ong JM, Aoki AM, Seigel GM, Sacerio I, Castellon R, Nesburn AB, Kenney MC. Oxysterol-induced toxicity in R28 and ARPE-19 cells. Neurochem Res 2003; 28:883-91. [PMID: 12718442 DOI: 10.1023/a:1023223409798] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
Studies have shown an intimate relationship between cholesterol and retinal diseases; we examined the effects of cholesterol oxides on cultured cells. Using the rat retinal precursor cell line R28 and the human RPE cell line ARPE-19, we investigated the potential cytotoxicity of cholesterol oxides. Cultured R28 and ARPE-19 cells were treated with either 25-hydroxycholesterol and 7-ketocholesterol (0-50 microg/ml). Cell viability was determined by the WST-1 colorimetric assay. Production of reactive oxygen intermediate (ROI) was assessed by a fluorescent probe-based assay (2',7'-dichlorodihydrofluorescein diacetate [H2DCFDA]). To detect the presence of apoptosis, DNA fragmentation gel analysis and Hoescht nuclear staining were performed. Both cholesterol oxides tested were toxic in a time- and dose-dependent fashion to the two cell lines used in this study. Treatment of R28 cells with either 25-hydroxycholesterol or 7-ketocholesterol at a concentration of 25 micro/ml resulted in greater than 50% loss of cell viability after 24 h. ARPE-19 cells were slightly less affected, with a loss of cell viability of approximately 20% and 40% after 24 h-exposure of 25-hydroxycholesterol and 7-ketocholesterol, respectively. DNA fragmentation and chromatin condensation demonstrated apoptotic events occurring in 7-ketocholesterol-treated cells. The fluorescent assay for ROI production showed that after an hour of exposure to 7-ketocholesterol, R28 cells responded with increased levels of ROIs, whereas no immediate production of ROIs were detected with treated ARPE-19 cells. These in vitro findings provide evidence that cholesterol oxides can directly damage cultured retinal and RPE cells. The oxysterol-induced oxidative stress in these cells may be a factor in the pathology of retinal degenerative diseases.
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Affiliation(s)
- John M Ong
- Molecular Eye Research Laboratory, Burns and Allen Research Institute, Cedars-Sinai Medical Center, Los Angeles, California 90048, USA.
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Ambati J, Ambati BK, Yoo SH, Ianchulev S, Adamis AP. Age-related macular degeneration: etiology, pathogenesis, and therapeutic strategies. Surv Ophthalmol 2003; 48:257-93. [PMID: 12745003 DOI: 10.1016/s0039-6257(03)00030-4] [Citation(s) in RCA: 609] [Impact Index Per Article: 29.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Age-related macular degeneration is the principal cause of registered legal blindness among those aged over 65 in the United States, western Europe, Australia, and Japan. Despite intensive research, the precise etiology of molecular events that underlie age-related macular degeneration is poorly understood. However, investigations on parallel fronts are addressing this prevalent public health problem. Sophisticated biochemical and biophysical techniques have refined our understanding of the pathobiology of drusen, geographic atrophy, and retinal pigment epithelial detachments. Epidemiological identification of risk factors has facilitated an intelligent search for underlying mechanisms and fueled clinical investigation of behavior modification. Gene searches have not only brought us to the cusp of identifying the culpable gene loci in age-related macular degeneration, but also localized genes responsible for other macular dystrophies. Recent and ongoing investigations, often cued by tumor biology, have revealed an important role for various growth factors, particularly in the neovascular form of the condition. Transgenic and knockout studies have provided important mechanistic insights into the development of choroidal neovascularization, the principal cause of vision loss in age-related macular degeneration. This in turn has culminated in preclinical and clinical trials of directed molecular interventions.
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Affiliation(s)
- Jayakrishna Ambati
- Ocular Angiogenesis Laboratory, Department of Ophthalmology, University of Kentucky, Lexington, USA
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188
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Evereklioglu C, Doganay S, Er H, Cekmen M, Ozerol E, Otlu B. Serum leptin concentrations are decreased and correlated with disease severity in age-related macular degeneration: a preliminary study. Eye (Lond) 2003; 17:350-5. [PMID: 12724698 DOI: 10.1038/sj.eye.6700345] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022] Open
Abstract
BACKGROUND Age-related maculopathy (ARM) or degeneration (ARMD) is the leading cause of irreversible blindness in developed countries. Despite several studies on the morphology of ARMD, the aetiology is unknown and factor(s) contributing to the pathogenesis remain to be characterised. More recent studies have demonstrated that cholesterol esters and lipids are present within Bruch's membrane deposits and drusen, and dietary fat intake is associated with ARMD. The product of Ob gene, leptin, is a recently discovered peptide participating in human metabolism. There is a direct relationship between serum leptin and diet, and lipoprotein metabolism, but the role of leptin in the course of ARMD has not previously been investigated. PURPOSE This cross-sectional case-control study investigated whether serum leptin level was associated with ARMD as a new possible risk factor and to assess its relationship with disease severity. Methods A total of 32 patients with ARM or ARMD (17 men, 15 women) and 20 age- and sex-matched healthy control subjects without ARMD (11 men, nine women) from a similar ethnic background were enrolled in this multicentre study. Body mass index (BMI) (weight (kg)/height (m(2))) was calculated for each group. The presence of maculopathy was assessed on the basis of colour fundus photographs using an international classification system. Patients were classified as early-ARM (n=16) or late-ARMD (n=16) using clinical examination and grading of photographs. Serum leptin levels were measured by an enzyme-linked immunosorbent assay kit. The Mann-Whitney U test or chi(2) test was used for statistics as indicated, and P&<0.05 was considered to be significant. RESULTS The age, sex ratio, and BMI between groups were comparable. Patients with maculopathy had significantly (P&<0.001) lower leptin levels (mean+/-SD, 6.01+/-2.55 ng/ml) than control subjects (13.21+/-2.27 ng/ml). In addition, late-ARMD patients had significantly lower leptin levels (3.81+/-0.58 ng/ml) than early-ARM patients (8.21+/-1.68 ng/ml, P&<0.001) or control subjects (P&<0.001). CONCLUSION Leptin seems to be a possible newly associated factor in the course of ARM and may be involved in the lipid composition of the macular lesions, especially in late-ARMD.
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Affiliation(s)
- C Evereklioglu
- Department of Ophthalmology, Erciyes University Medical Faculty, TR-38020 Kayseri, Turkey.
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189
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Heuberger RA, Fisher AI, Jacques PF, Klein R, Klein BEK, Palta M, Mares-Perlman JA. Relation of blood homocysteine and its nutritional determinants to age-related maculopathy in the third National Health and Nutrition Examination Survey. Am J Clin Nutr 2002; 76:897-902. [PMID: 12324306 DOI: 10.1093/ajcn/76.4.897] [Citation(s) in RCA: 48] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
BACKGROUND Blood homocysteine and its nutritional determinants folate and cyanocobalamin (vitamin B-12) have been shown to affect the risk of vascular disease. The pathogenesis of age-related maculopathy (ARM) is related to adverse vascular changes. OBJECTIVE The objective was to evaluate the associations between homocysteine, its nutritional determinants, and ARM in persons aged >or= 40 y participating in the third National Health and Nutrition Examination Survey. DESIGN A nonmydriatic fundus photograph of one eye, taken in a mobile examination center, was used to ascertain ARM status. Phlebotomy was performed for measurement of homocysteine, cyanocobalamin, and erythrocyte folate in participants of phase 2 of the survey (n = 3828). Logistic regressions were used to compute odds ratios and 95% CIs by quintile of serum analyte by using sample weights and jackknife replication methods to adjust for the complex survey design. The final analyses were adjusted for potential risk factors that influenced odds ratios. RESULTS Total serum homocysteine, red blood cell folate, and serum cyanocobalamin were unrelated to ARM in the overall sample. However, red blood cell folate was inversely related to one type of early ARM lesion (soft drusen) in non-Hispanic blacks. CONCLUSIONS ARM does not appear to be associated with homocysteine or its dietary determinants in this survey. There is a need for further investigation to rule out potential associations in subgroups with low folate status that may not have been detected because of the cross-sectional survey design.
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Affiliation(s)
- Roschelle A Heuberger
- Department of Ophthalmology, University of Wisconsin Medical School, Madison 53705-2397, USA
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190
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Abstract
Age-related macular degeneration (AMD) is the leading cause of irreversible vision loss in the United States and other western nations. Limited treatment is available, and there are no established means of prevention. The detection of modifiable risk factors is important to suggest preventive behaviors that can reduce disease occurrence or prevent the progression to the late stages of AMD. Results of recent studies suggest that the etiology and pathogenesis of AMD are a complex interaction of genetic and external factors. Although a number of factors seem promising, only age and cigarette smoking are confirmed as increasing AMD risk. Other factors that most likely play a significant role in AMD are nutritional factors, e.g., antioxidants, and hypertension or other underlying atherosclerotic disease processes. The results of the Age-Related Eye Disease Study suggest a moderate beneficial effect of antioxidant, vitamin, and zinc supplementation in reducing progression to severe AMD.
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Affiliation(s)
- Leslie Hyman
- Stony Brook University, Department of Preventive Medicine, Stony Brook, New York 11794-8036, USA.
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191
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Frock TL. Gaining insight into age-related macular degeneration. JOURNAL OF THE AMERICAN ACADEMY OF NURSE PRACTITIONERS 2002; 14:207-13. [PMID: 12051144 DOI: 10.1111/j.1745-7599.2002.tb00115.x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
PURPOSE/OBJECTIVE To enhance nurse practitioner (NP) recognition of clients with age-related macular degeneration (AMD) based on history and physical examination findings, to encourage prompt initial referral of these clients to an ophthalmologist for a treatment evaluation, and to acquaint NPs with low vision rehabilitation services. DATA SOURCES Government documents, professional association practice guidelines, original research articles, journal articles, and Internet resources. CONCLUSIONS Age-related macular degeneration is a common, chronic vision-threatening condition necessitating prompt recognition and professional evaluation. If not recognized early, AMD can lead to low vision and a diminished quality of life for the elderly client. IMPLICATIONS FOR PRACTICE Even though NPs have a limited role in the treatment of AMD, they are in an instrumental position as a primary care providers to screen for this disease chiefly by: (a) adherence to eye examinations intervals, (b) recognition of risk factors, (c) use of the Amsler grid, (d) awareness of psychosocial dimensions, (e) making appropriate referrals, and (f) advocating low vision rehabilitation services.
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192
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MacDonald IM. What are your patients reading? CANADIAN JOURNAL OF OPHTHALMOLOGY 2002; 37:141, 143. [PMID: 12083472 DOI: 10.1016/s0008-4182(02)80054-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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193
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MacDonald IM. Ce que lisent nos patients. Can J Ophthalmol 2002. [DOI: 10.1016/s0008-4182(02)80055-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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194
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Donoso LA, Edwards AO, Frost A, Vrabec T, Stone EM, Hageman GS, Perski T. Autosomal dominant Stargardt-like macular dystrophy. Surv Ophthalmol 2001; 46:149-63. [PMID: 11578648 DOI: 10.1016/s0039-6257(01)00251-x] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Autosomal dominant Stargardt-like macular dystrophy is one of the early onset macular dystrophies. It is characterized clinically in its early stages by visual loss and by the presence of atrophic macular changes with or without the presence of yellowish flecks. It is an important retinal dystrophy to study, not only because it has implications in the care and treatment of patients with the condition, but because it also provides important information regarding retinal function. Review of the literature suggests that many of the reported families are linked to chromosome 6q. Genetic and genealogical evidence suggests that these families have descended from a common ancestor or founder. The recent identification of a disease-causing gene that is involved in fatty acid metabolism may have implications in the study of the more common age-related macular degeneration. We review the recent clinical, genetic, and genealogical aspects of autosomal dominant Stargardt-like macular dystrophy.
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Affiliation(s)
- L A Donoso
- Henry and Corinne Bower Laboratory for Macular Degeneration, Eye Research Institute, Wills Eye Hospital, Philadelphia, PA 19107, USA.
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