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1.
J Am Med Dir Assoc ; 21(2): 240-247.e5, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31401047

RESUMO

OBJECTIVES: To examine the associations between 3 frailty instruments and circulating micronutrients in a large representative sample of older adults. DESIGN: Cross-sectional data from a nationally representative cohort study conducted between October 2009 and July 2011. PARTICIPANTS AND SETTING: Adults age ≥50 years (n = 4068) living in the community in Ireland. MEASUREMENTS: Circulating micronutrients (lutein, zeaxanthin, folate, vitamin B-12, and vitamin D) were measured, transformed, and standardized. Frailty was assessed using the Frailty Phenotype, the Frailty Index, and the FRAIL Scale (fatigue, resistance, ambulation, illnesses, and loss of weight), instruments. Multinomial logistic regression determined associations between micronutrients and prefrailty or frailty. Models were adjusted for sociodemographic, lifestyle, health, and seasonal factors. RESULTS: Adjusting for age, sex, and educational attainment, all 3 measures of frailty were associated with lower levels of lutein [relative risk ratios (RRRs): 0.43‒0.63], zeaxanthin (RRRs: 0.49‒0.63), and vitamin D (RRRs: 0.51‒0.75), and with the accumulation of micronutrient insufficiencies (RRRs: 1.42‒1.90). Attenuated but significant associations were also observed with all measures of prefrailty for lutein, vitamin D, and number of micronutrient insufficiencies. The associations with frailty persisted following additional adjustment for social, lifestyle, and health and seasonal factors, and following multiple test correction. CONCLUSIONS AND IMPLICATIONS: We have presented the most consistent evidence in the largest study to date that micronutrient concentrations are associated with prefrailty and frailty in older adults. Our data suggest that low micronutrient status has potential as an easily modifiable marker and intervention target for frailty and supports further investigation into micronutrient supplementation and fortification to prevent frailty and disability among older adults.


Assuntos
Biomarcadores , Fragilidade , Idoso , Envelhecimento , Estudos de Coortes , Estudos Transversais , Idoso Fragilizado , Fragilidade/diagnóstico , Fragilidade/epidemiologia , Humanos , Irlanda , Estudos Longitudinais , Micronutrientes , Pessoa de Meia-Idade
3.
J Alzheimers Dis ; 61(3): 947-961, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29332050

RESUMO

BACKGROUND: There is a biologically plausible rationale whereby the dietary carotenoids lutein (L), zeaxanthin (Z), and meso-zeaxanthin (MZ), which are collectively referred to as macular pigment (MP) in the central retina (macula), support the maintenance of cognition via their antioxidant and anti-inflammatory properties. OBJECTIVE: To investigate the impact of supplemental L, Z, and MZ on memory, executive function, and verbal fluency among healthy individuals with low MP levels. METHODS: In this double-blind, placebo-controlled, randomized clinical trial, subjects (n = 91; mean±SD age = 45.42±12.40; % male = 51.6) consumed a daily formulation of 10 mg L, 10 mg MZ, and 2 mg Z (n = 45) or placebo (n = 46) for 12 months. Cognitive domains assessed included verbal and visual learning, immediate and delayed memory, executive function, and verbal fluency. MP and serum carotenoid concentrations of L, Z, and MZ were also measured. RESULTS: Following 12-month supplementation, individuals in the active group exhibited statistically significant improvements in memory when compared to the placebo group (paired associated learning [PAL] memory score [rANOVA, p = 0.009]; PAL errors [rANOVA, p = 0.017]). Furthermore, the observed reduction in the number of errors made in the PAL task among those in the intervention group was positively and significantly related to observed increases in MP volume (p = 0.005) and observed increases in serum concentrations of L (p = 0.009). CONCLUSION: This randomized, double-blind, placebo-controlled clinical trial demonstrates a memory-enhancing effect of daily supplementation with L, Z, and MZ in healthy subjects with low MP at baseline. The implications of these findings for intellectual performance throughout life, and for risk of cognitive decline in later life, warrant further study.


Assuntos
Suplementos Nutricionais/análise , Luteína/farmacologia , Pigmento Macular/fisiologia , Memória Episódica , Retina/efeitos dos fármacos , Adulto , Cognição , Método Duplo-Cego , Função Executiva , Feminino , Voluntários Saudáveis , Humanos , Luteína/administração & dosagem , Masculino , Pessoa de Meia-Idade , Retina/fisiologia , Testes Visuais , Zeaxantinas/administração & dosagem , Zeaxantinas/farmacologia
4.
Curr Eye Res ; 43(3): 383-390, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29172786

RESUMO

PURPOSE: To investigate plasma lutein (L) and zeaxanthin (Z) concentrations with grading-confirmed and self-reported prevalence of age-related macular degeneration (AMD). MATERIAL AND METHODS: Data collected from a nationally representative prospective cohort study of community-dwelling adults aged 50 years and over in the Republic of Ireland. Participants underwent a computer-assisted personal interview and a center-based health assessment. Plasma concentrations of L and total Z (Z and meso-zeaxanthin [MZ]) were measured by high performance liquid chromatography, and retinal photographs were graded using a version of the AMD International Classification and Grading System. Consumption of supplements containing L and/or Z and/or MZ was recorded as supplement use. Four groups were identified: Group 1 (n = 24): AMD-afflicted and correctly aware; Group 2 (n = 264): AMD-afflicted but unaware; Group 3 (n = 41): AMD-free and incorrectly believed that they were afflicted with the condition; Group 4 (n = 4094): AMD-free and correctly self-reported absence of AMD. RESULTS: Of 4,423 participants with plasma concentrations of L and Z and gradable retinal photographs, 288 (6.5%) were afflicted with AMD, and 65 (1.5%) self-reported AMD. Controlling for family history and age, the relationship between grading-confirmed AMD and plasma L was positive and significant (p < 0.001). Mean plasma concentrations of L in Group 2 (mean = 0.2162 ± 0.132 µmol) and Group 4 (mean = 0.2040 ± 0.121 µmol/L) were significantly lower than Group 1 (mean = 0.4691 ± 0.0.372 µmol/L) and Group 3 (mean = 0.3176 ± 0.0.235 µmol/L). Supplement use was reported by 41.7% and 17.1% of participants in Groups 1 and 3, respectively, but only 2.7% and 1.9% of participants in Groups 2 and 4, respectively. CONCLUSION: A belief that one suffers from AMD, whether justified or not, is associated with supplement use and with higher plasma concentrations of L.


Assuntos
Luteína/sangue , Macula Lutea/patologia , Degeneração Macular/epidemiologia , Vigilância da População/métodos , Zeaxantinas/sangue , Idoso , Feminino , Seguimentos , Humanos , Irlanda/epidemiologia , Degeneração Macular/sangue , Degeneração Macular/diagnóstico , Masculino , Pessoa de Meia-Idade , Prevalência , Estudos Prospectivos , Autorrelato
5.
Invest Ophthalmol Vis Sci ; 58(12): 5347-5360, 2017 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-29053808

RESUMO

Purpose: The purpose of this study was to evaluate the impact of supplemental macular carotenoids (including versus not including meso-zeaxanthin) in combination with coantioxidants on visual function in patients with nonadvanced age-related macular degeneration. Methods: In this study, 121 participants were randomly assigned to group 1 (Age-Related Eye Disease Study 2 formulation with a low dose [25 mg] of zinc and an addition of 10 mg meso-zeaxanthin; n = 60) or group 2 (Age-Related Eye Disease Study 2 formulation with a low dose [25 mg] of zinc; n = 61). Visual function was assessed using best-corrected visual acuity, contrast sensitivity (CS), glare disability, retinal straylight, photostress recovery time, reading performance, and the National Eye Institute Visual Function Questionnaire-25. Macular pigment was measured using customized heterochromatic flicker photometry. Results: There was a statistically significant improvement in the primary outcome measure (letter CS at 6 cycles per degree [6 cpd]) over time (P = 0.013), and this observed improvement was statistically comparable between interventions (P = 0.881). Statistically significant improvements in several secondary outcome visual function measures (letter CS at 1.2 and 2.4 cpd; mesopic and photopic CS at all spatial frequencies; mesopic glare disability at 1.5, 3, and 6 cpd; photopic glare disability at 1.5, 3, 6, and 12 cpd; photostress recovery time; retinal straylight; mean and maximum reading speed) were also observed over time (P < 0.05, for all), and were statistically comparable between interventions (P > 0.05, for all). Statistically significant increases in macular pigment at all eccentricities were observed over time (P < 0.0005, for all), and the degree of augmentation was statistically comparable between interventions (P > 0.05). Conclusions: Antioxidant supplementation in patients with nonadvanced age-related macular degeneration results in significant increases in macular pigment and improvements in CS and other measures of visual function. (Clinical trial, http://www.isrctn.com/ISRCTN13894787).


Assuntos
Antioxidantes/administração & dosagem , Luteína/uso terapêutico , Degeneração Macular/tratamento farmacológico , Pigmento Macular/uso terapêutico , Acuidade Visual/fisiologia , Idoso , Ácido Ascórbico/administração & dosagem , Sensibilidades de Contraste/fisiologia , Método Duplo-Cego , Quimioterapia Combinada , Feminino , Ofuscação , Humanos , Degeneração Macular/fisiopatologia , Masculino , Pessoa de Meia-Idade , Fotometria/métodos , Leitura , Oligoelementos/administração & dosagem , Vitamina E/administração & dosagem , Zeaxantinas/uso terapêutico , Zinco/administração & dosagem
6.
Br J Nutr ; 117(1): 108-123, 2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-28122649

RESUMO

The macular carotenoids lutein (L), zeaxanthin (Z) and meso-zeaxanthin (MZ) accumulate at the macula, where they are collectively referred to as macular pigment (MP). Augmentation of this pigment, typically achieved through diet and supplementation, enhances visual function and protects against progression of age-related macular degeneration. However, it is known that eggs are a rich dietary source of L and Z, in a highly bioavailable matrix. In this single-blind placebo-controlled study, L- and MZ-enriched eggs and control non-enriched eggs were fed to human subjects (mean age 41 and 35 years, respectively) over an 8-week period, and outcome measures included MP, visual function and serum concentrations of carotenoids and cholesterol. Serum carotenoid concentrations increased significantly in control and enriched egg groups, but to a significantly greater extent in the enriched egg group (P<0·001 for L, Z and MZ). There was no significant increase in MP in either study group post intervention, and we saw no significant improvement in visual performance in either group. Total cholesterol increased significantly in each group, but it did not exceed the upper limit of the normative range (6·5 mmol/l). Therefore, carotenoid-enriched eggs may represent an effective dietary source of L, Z and MZ, reflected in significantly raised serum concentrations of these carotenoids, and consequentially improved bioavailability for capture by target tissues. However, benefits in terms of MP augmentation and /or improved visual performance were not realised over the 8-week study period, and a study of greater duration will be required to address these questions.


Assuntos
Dieta , Ovos/análise , Macula Lutea/efeitos dos fármacos , Xantofilas/farmacologia , Adulto , Feminino , Análise de Alimentos , Humanos , Masculino , Pessoa de Meia-Idade , Fenômenos Fisiológicos da Nutrição , Visão Ocular/efeitos dos fármacos , Xantofilas/administração & dosagem , Xantofilas/química
7.
Invest Ophthalmol Vis Sci ; 57(7): 3429-39, 2016 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-27367585

RESUMO

PURPOSE: The high-performance visual function associated with central vision is mediated by the macula (the central retina), which accumulates three diet-derived pigments (the carotenoids lutein [L], zeaxanthin [Z], and meso-zeaxanthin [MZ]). Our study sought to investigate the impact on visual function, including contrast sensitivity (CS), of supplementation with these naturally occurring carotenoids, in individuals with low retinal concentrations. METHODS: Subjects consumed daily a formulation containing 10 mg L, 2 mg Z, and 10 mg MZ (active group; n = 53) or placebo (n = 52) for a period of 12 months. Study visits were at baseline, 3, 6, and 12 months. Contrast sensitivity at 6 cycles per degree (cpd) was the primary outcome measure (POM). Secondary outcome measures included CS at other spatial frequencies, best-corrected visual acuity (BCVA), glare disability, photostress recovery, and light scatter. Macular pigment optical density (MPOD) was measured using dual-wavelength autofluorescence, and serum carotenoid concentrations were analyzed using high performance liquid chromatography (HPLC). RESULTS: Compared to placebo, statistically significant improvements from baseline CS were detected at 6 (P = 0.002) and 1.2 (P = 0.004) cpd in the active group. Additionally, improvements in CS were commensurate with the observed increases in retinal concentrations of these carotenoids (r = 0.342, P = 0.002 at 6 cpd). CONCLUSIONS: These results indicate that dietary fortification with the macular carotenoids can have meaningful effects on visual function.


Assuntos
Sensibilidades de Contraste/efeitos dos fármacos , Suplementos Nutricionais , Luteína/farmacologia , Pigmento Macular/fisiologia , Zeaxantinas/farmacologia , Adulto , Análise de Variância , Feminino , Humanos , Luteína/administração & dosagem , Luteína/sangue , Macula Lutea/fisiopatologia , Pigmento Macular/metabolismo , Masculino , Pessoa de Meia-Idade , Recuperação de Função Fisiológica/efeitos dos fármacos , Estresse Psicológico , Acuidade Visual/efeitos dos fármacos , Zeaxantinas/administração & dosagem , Zeaxantinas/sangue
8.
Eur Food Res Technol ; 242: 599-608, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27069419

RESUMO

We investigated the concordance between actual and declared content of the three macular carotenoids in commercially available supplements aimed at eye health. Three batches of nine products were tested for content of lutein (L), zeaxanthin (Z) and meso-zeaxanthin (MZ) by chiral HPLC-DAD. In every product tested, actual L concentration was close to target, but Z concentration varied greatly (47-248 % of declared concentration), and the L:Z ratio within some supplements was adversely affected in consequence. In six of seven products not declaring MZ, we found this carotenoid, and four of them, using the same L source, contained a concentration of MZ that correlated positively and significantly with measured concentrations of L (r2 = 0.86; P < 0.001). More transparency is needed in terms of concordance between actual and declared concentrations of Z in commercially available formulations, and MZ should be declared in those formulations where it is present.

9.
J Nutr Sci ; 5: e1, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26793307

RESUMO

The xanthophyll carotenoids lutein (L), zeaxanthin (Z) and meso-zeaxanthin (MZ) are found at the macula, the central part of the retina, where they are referred to as macular pigment (MP). MP is studied in human subjects because of its proven role in enhancing visual function and its putative role in protecting against age-related macular degeneration. These benefits are probably due to the antioxidant and short-wavelength filtering properties of MP. It is known that eggs are a dietary source of L and Z. This experiment was designed to measure the egg yolk carotenoid response to hen supplementation with L, Z and MZ. A total of forty hens were used in the trial and were divided into eight groups of five hens. Each group was supplemented (with about 140 mg active xanthophylls/kg feed) with one of the following oil-based carotenoid formulations for 6 weeks: unesterified L (group 1); L diacetate (group 2); unesterified Z (group 3); Z diacetate (group 4); unesterified MZ (group 5); MZ diacetate (group 6); L-MZ (1:1) diacetate mixture (group 7); L-MZ diacetate (1:3) mixture (group 8). Yolk carotenoid content was analysed weekly (in four randomly selected eggs) by HPLC. We found that hens supplemented with Z diacetate and MZ diacetate produced eggs with significantly greater carotenoid concentrations than their free form counterparts. This finding potentially represents the development of a novel food, suitable to increase MP and its constituent carotenoids in serum.

10.
Invest Ophthalmol Vis Sci ; 56(13): 8207-14, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26720473

RESUMO

PURPOSE: We compared macular pigment (MP) measurements using customized heterochromatic flicker photometry (Macular Metrics Densitometer) and dual-wavelength fundus autofluorescence (Heidelberg Spectralis HRA + OCT MultiColor) in subjects with early age-related macular degeneration (AMD). METHODS: Macular pigment was measured in 117 subjects with early AMD (age, 44-88 years) using the Densitometer and Spectralis, as part of the Central Retinal Enrichment Supplementation Trial (CREST; ISRCTN13894787). Baseline and 6-month study visits data were used for the analyses. Agreement was investigated at four different retinal eccentricities, graphically and using indices of agreement, including Pearson correlation coefficient (precision), accuracy coefficient, and concordance correlation coefficient (ccc). RESULTS: Agreement was poor between the Densitometer and Spectralis at all eccentricities, at baseline (e.g., at 0.25° eccentricity, accuracy = 0.63, precision = 0.35, ccc = 0.22) and at 6 months (e.g., at 0.25° eccentricity, accuracy = 0.52, precision = 0.43, ccc = 0.22). Agreement between the two devices was significantly greater for males at 0.5° and 1.0° of eccentricity. At all eccentricities, agreement was unaffected by cataract grade. CONCLUSIONS: In subjects with early AMD, MP measurements obtained using the Densitometer and Spectralis are not statistically comparable and should not be used interchangeably in either the clinical or research setting. Despite this lack of agreement, statistically significant increases in MP, following 6 months of supplementation with macular carotenoids, were detected with each device, confirming that these devices are capable of measuring change in MP within subjects over time. (http://www.controlled-trials.com number, ISRCTN13894787.).


Assuntos
Angiofluoresceinografia/métodos , Degeneração Macular/metabolismo , Pigmento Macular/metabolismo , Fotometria/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Densitometria/métodos , Feminino , Fundo de Olho , Humanos , Degeneração Macular/diagnóstico , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes
11.
J Alzheimers Dis ; 44(4): 1157-69, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25408222

RESUMO

BACKGROUND: Patients with Alzheimer's disease (AD) exhibit significantly less macular pigment (MP) and poorer vision when compared to control subjects. OBJECTIVE: To investigate supplementation with the macular carotenoids on MP, vision, and cognitive function in patients with AD versus controls. METHODS: A randomized, double-blind clinical trial with placebo and active arms. 31 AD patients and 31 age-similar control subjects were supplemented for six months with either Macushield (10 mg meso-zeaxanthin [MZ]; 10 mg lutein [L]; 2 mg zeaxanthin [Z]) or placebo (sunflower oil). MP was measured using dual-wavelength autofluorescence (Heidelberg Spectralis®). Serum L, Z, and MZ were quantified by high performance liquid chromatography. Visual function was assessed by best corrected visual acuity and contrast sensitivity (CS). Cognitive function was assessed using a battery of cognition tests, including the Cambridge Neuropsychological Test Automated Battery (CANTAB)). RESULTS: Subjects on the active supplement (for both AD and non-AD controls) exhibited statistically significant improvement in serum concentrations of L, Z, MZ, and MP (p < 0.001, for all) and also CS at (p = 0.039). Also, for subjects on the active supplement, paired samples t-tests exhibited four significant results (from five spatial frequencies tested) in the AD group, and two for the non-AD group, and all indicating improvements in CS. We found no significant changes in any of the cognitive function outcome variables measured (p > 0.05, for all). CONCLUSION: Supplementation with the macular carotenoids (MZ, Z, and L) benefits patients with AD, in terms of clinically meaningful improvements in visual function and in terms of MP augmentation.


Assuntos
Doença de Alzheimer/dietoterapia , Antioxidantes/uso terapêutico , Carotenoides/uso terapêutico , Transtornos Cognitivos/dietoterapia , Suplementos Nutricionais , Idoso , Idoso de 80 Anos ou mais , Doença de Alzheimer/complicações , Carotenoides/sangue , Cromatografia Líquida de Alta Pressão , Transtornos Cognitivos/etiologia , Sensibilidades de Contraste/efeitos dos fármacos , Método Duplo-Cego , Feminino , Humanos , Estudos Longitudinais , Luteína , Pigmento Macular/metabolismo , Masculino , Entrevista Psiquiátrica Padronizada , Testes Neuropsicológicos , Acuidade Visual/efeitos dos fármacos , Zeaxantinas
12.
Graefes Arch Clin Exp Ophthalmol ; 253(8): 1231-43, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25311651

RESUMO

PURPOSE: Our aim was to investigate the macular response to three different supplements containing lutein (L), zeaxanthin (Z) and meso-zeaxanthin (MZ) in normal subjects and those with age-related macular degeneration (AMD). MATERIALS AND METHODS: Macular pigment optical density (MPOD) and serum xanthophyll concentrations were measured in normal (n = 31) and AMD subjects (n = 32), randomly assigned to: group 1 (20 mg L, 2 mg Z, 0.3 mg MZ), group 2 (10 mg L, 2 mg Z, 10 mg MZ) or group 3 (3 mg L, 2 mg Z, 17 mg MZ). MPOD was measured at baseline, 2, 4, 6 and 8 weeks and at 0.25°, 0.5°, 1.0° and 1.75° of eccentricity using customised heterochromatic flicker photometry and serum xanthophylls by HPLC. RESULTS: MPOD increased significantly at all eccentricities in each group (p < 0.05), except at 1.75° in group 3 (p = 0.242). There was no difference in MPOD measurements between AMD and normal subjects, except for group 2, where AMD subjects exhibited a greater response at 1.75° (p = 0.012). Final serum concentrations of MZ were positively and significantly related to final MPOD values at each eccentricity in all subjects. Targeted analysis of those subjects receiving the MZ-containing supplements exhibited stronger relationships between serum MZ concentrations and MPOD at 0.25° in group 3 than group 2; in group 2 all associations were positive, but only significant at 1.75°. CONCLUSIONS: Serum concentrations of MZ were strongly correlated with MPOD after 8 weeks of supplementation with the group 3 formulation, but the inclusion of L in the group 2 formulation may result in greater MPOD augmentation across the spatial profile.


Assuntos
Luteína/administração & dosagem , Degeneração Macular/tratamento farmacológico , Pigmento Macular/sangue , Zeaxantinas/administração & dosagem , Idoso , Cromatografia Líquida de Alta Pressão , Densitometria , Dieta , Método Duplo-Cego , Composição de Medicamentos , Feminino , Voluntários Saudáveis , Humanos , Luteína/sangue , Degeneração Macular/sangue , Masculino , Pessoa de Meia-Idade , Xantofilas/sangue , Zeaxantinas/sangue
13.
J Alzheimers Dis ; 42(4): 1191-202, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25024317

RESUMO

BACKGROUND: The macula (central retina) contains a yellow pigment, comprising the dietary carotenoids lutein (L), zeaxanthin (Z), and meso-zeaxanthin, known as macular pigment (MP). The concentrations of MP's constituent carotenoids in retina and brain tissue correlate, and there is a biologically-plausible rationale, supported by emerging evidence, that MP's constituent carotenoids are also important for cognitive function. OBJECTIVE: To investigate if patients with Alzheimer's disease (AD) are comparable to controls in terms of MP and visual function. METHODS: 36 patients with moderate AD and 33 controls with the same age range participated. MP was measured using dual-wavelength autofluorescence (Heidelberg Spectralis®); cognitive function was assessed using a battery of cognition tests (including Cambridge Neuropsychological Test Automated Battery). Visual function was recorded by measuring best corrected visual acuity (BCVA) and contrast sensitivity (CS). Serum L and Z concentrations (by HPLC) and age-related macular degeneration (AMD, by retinal examination) status were also assessed. RESULTS: In the AD group, central MP (i.e., at 0.23°) and MP volume were significantly lower than the control group (p < 0.001 for both), as were measures of BCVA, CS, and serum L and Z concentrations (p < 0.05, for all). CONCLUSION: AD patients were observed to exhibit significantly less MP, lower serum concentrations of L and Z, poorer vision, and a higher occurrence of AMD when compared to control subjects. A clinical trial in AD patients designed to investigate the impact of macular carotenoid supplementation with respect to MP, visual function, and cognitive function is merited.


Assuntos
Doença de Alzheimer/fisiopatologia , Doença de Alzheimer/psicologia , Degeneração Macular/fisiopatologia , Pigmento Macular/metabolismo , Acuidade Visual , Idoso , Idoso de 80 Anos ou mais , Doença de Alzheimer/patologia , Dieta , Feminino , Humanos , Luteína/administração & dosagem , Luteína/sangue , Degeneração Macular/patologia , Masculino , Pessoa de Meia-Idade , Testes Neuropsicológicos , Retina/patologia , Zeaxantinas/administração & dosagem , Zeaxantinas/sangue
14.
Retina ; 34(9): 1757-66, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24887490

RESUMO

PURPOSE: To investigate the impact of three different macular carotenoid formulations on macular pigment optical density and visual performance in subjects with early age-related macular degeneration. METHODS: Fifty-two subjects were supplemented and followed for 12 months, 17 of them were in intervention Group 1 (20 mg/day lutein and 2 mg/day zeaxanthin); 21 in Group 2 (10 mg/day meso-zeaxanthin, 10 mg/day lutein, and 2 mg/day zeaxanthin); and 14 in Group 3 (17 mg/day meso-zeaxanthin, 3 mg/day lutein, and 2 mg/day zeaxanthin). The macular pigment optical density was measured using customized heterochromatic flicker photometry, and visual function was assessed using corrected distance visual acuity and by letter contrast sensitivity. RESULTS: A statistically significant increase in the macular pigment optical density was observed at all measured eccentricities in Group 2 (P ≤ 0.005) and in Group 3 (P < 0.05, for all), but only at 1.75° in Group 1 (P = 0.018). Statistically significant (P < 0.05) improvements in letter contrast sensitivity were seen at all spatial frequencies (except 1.2 cycles per degree) in Group 3, and at low spatial frequencies in Groups 1 and 2. CONCLUSION: Augmentation of the macular pigment optical density across its spatial profile and enhancements in contrast sensitivity were best achieved after supplementation with a formulation containing high doses of meso-zeaxanthin in combination with lutein and zeaxanthin.


Assuntos
Sensibilidades de Contraste/efeitos dos fármacos , Luteína/administração & dosagem , Degeneração Macular/tratamento farmacológico , Pigmento Macular/metabolismo , Acuidade Visual/efeitos dos fármacos , Zeaxantinas/administração & dosagem , Administração Oral , Idoso , Quimioterapia Combinada , Feminino , Humanos , Degeneração Macular/fisiopatologia , Masculino , Pessoa de Meia-Idade , Preparações Farmacêuticas , Fotometria , Método Simples-Cego
15.
Ophthalmic Epidemiol ; 21(2): 111-23, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24621122

RESUMO

PURPOSE: The Central Retinal Enrichment Supplementation Trials (CREST) aim to investigate the potential impact of macular pigment (MP) enrichment, following supplementation with a formulation containing 10 mg lutein (L), 2 mg zeaxanthin (Z) and 10 mg meso-zeaxanthin (MZ), on visual function in normal subjects (Trial 1) and in subjects with early age-related macular degeneration (AMD; Trial 2). METHODS: CREST is a single center, double-blind, randomized clinical trial. Trial 1 (12-month follow-up) subjects are randomly assigned to a formulation containing 10 mg L, 10 mg MZ and 2 mg Z (n = 60) or placebo (n = 60). Trial 2 (24-month follow-up) subjects are randomly assigned to a formulation containing 10 mg L, 10 mg MZ, 2 mg Z plus 500 mg vitamin C, 400 IU vitamin E, 25 mg zinc and 2 mg copper (Intervention A; n = 75) or 10 mg L and 2 mg Z plus 500 mg vitamin C, 400 IU vitamin E, 25 mg zinc and 2 mg copper (Intervention B; n = 75). Contrast sensitivity (CS) at 6 cycles per degree represents the primary outcome measure in each trial. Secondary outcomes include: CS at other spatial frequencies, MP, best-corrected visual acuity, glare disability, photostress recovery, light scatter, cognitive function, foveal architecture, serum carotenoid concentrations, and subjective visual function. For Trial 2, AMD morphology, reading speed and reading acuity are also being recorded. CONCLUSIONS: CREST is the first study to investigate the impact of supplementation with all three macular carotenoids in the context of a large, double-blind, randomized clinical trial.


Assuntos
Sensibilidades de Contraste/efeitos dos fármacos , Luteína/administração & dosagem , Degeneração Macular/prevenção & controle , Vitaminas/administração & dosagem , Xantofilas/administração & dosagem , Adulto , Idoso , Suplementos Nutricionais , Método Duplo-Cego , Combinação de Medicamentos , Feminino , Seguimentos , Ofuscação , Voluntários Saudáveis , Humanos , Masculino , Preparações Farmacêuticas , Fotometria , Projetos de Pesquisa , Pigmentos da Retina , Perfil de Impacto da Doença , Inquéritos e Questionários , Tomografia de Coerência Óptica , Acuidade Visual/fisiologia , Zeaxantinas
16.
Exp Eye Res ; 115: 172-7, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23891863

RESUMO

Supplementation with carotenoids is proposed to protect against age-related macular degeneration. There is, however, considerable variability in retinal macular pigment response, which may be due to underlying genetic variation. The purpose of this study was to determine whether genetic factors, which have been previously associated with cross-sectional macular pigment levels in the retina or serum lutein, also influence response to supplementation. To this end we conducted an association study in 310 subjects from the TwinsUK cohort between variants in 8 candidate genes and serum lutein and retinal macular pigment optical density (MPOD) levels before and after supplementation. Four variants were associated with MPOD response to supplementation (p < 0.05): rs11057841 (SCARB1), rs4926339 (RPE65), rs1929841 (ABCA1) and rs174534 (FADS1). We also confirmed previous associations between rs6564851 near BMCO1 (p < 0.001) and rs11057841 within SCARB1 (p = 0.01) and baseline measures of serum lutein; while the latter was also associated with MPOD response, none of the BMCO1 variants were. Finally, there was evidence for association between variants near RPE65 and ELOVL2 and changes in lutein concentration after supplementation. This study is the first to show association between genetic variants and response to carotenoids supplementation. Our findings suggest an important link between MP response and the biological processes of carotenoids transport and fatty acid metabolism.


Assuntos
Luteína/administração & dosagem , Característica Quantitativa Herdável , Pigmentos da Retina/genética , Gêmeos Dizigóticos/genética , Gêmeos Monozigóticos/genética , Xantofilas/administração & dosagem , Transportador 1 de Cassete de Ligação de ATP/genética , Adulto , Cromatografia Líquida de Alta Pressão , Dessaturase de Ácido Graxo Delta-5 , Suplementos Nutricionais , Ácidos Graxos Dessaturases/genética , Feminino , Variação Genética , Genótipo , Humanos , Luteína/sangue , Pessoa de Meia-Idade , Polimorfismo de Nucleotídeo Único , Estudos Prospectivos , Pigmentos da Retina/metabolismo , Receptores Depuradores Classe B/genética , Xantofilas/sangue , Adulto Jovem , Zeaxantinas , cis-trans-Isomerases/genética
17.
Nutrients ; 5(6): 1962-9, 2013 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-23760061

RESUMO

Three dietary carotenoids, lutein (L), zeaxanthin (Z) and meso-zeaxanthin (MZ) accumulate at the central retina (macula), where they are collectively referred to as macular pigment (MP). MP's pre-receptoral absorption of blue light and consequential attenuation of the effects of chromatic aberration and light scatter are important for optimal visual function. Furthermore, antioxidant activity of MP's constituent carotenoids and the same blue light-filtering properties underlie the rationale for its putative protective role for age-related macular degeneration (AMD). Supplementation with L, Z and MZ augments MP and enhances visual performance in diseased and non-diseased eyes, and may reduce risk of AMD development and/or progression.


Assuntos
Suplementos Nutricionais , Luteína/administração & dosagem , Macula Lutea/efeitos dos fármacos , Visão Ocular/efeitos dos fármacos , Xantofilas/administração & dosagem , Dieta , Ofuscação , Humanos , Degeneração Macular/prevenção & controle , Neurofisiologia , Zeaxantinas
20.
Eur J Nutr ; 52 Suppl 1: 1-9, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23455383

RESUMO

Nutrients can be classified as either "essential" or "non-essential," the latter are also termed bioactive substances. Whereas the absence of essential nutrients from the diet results in overt deficiency often times with moderate to severe physiological decrements, the absence of bioactive substances from the diet results in suboptimal health. Nutrient reference values are set by Codex Alimentarius and regulatory bodies in many countries, mostly for essential nutrients with recommended daily intakes. The IOM in the United States has defined a set of four DRIs that, when data are appropriate, include an EAR, a RDA that is derived from the EAR, an AI for nutrients without appropriate data to identify an EAR, and an UL. From the RDA, the United States derives a labeling value called the DV, which applies to older children and most adults. In Codex, the equivalents of the DVs are the NRVs to be used in calculating percentage values on food labels. Nothing in the IOM documents specifies that labeling values can be set only for what have been defined to date as essential nutrients. Indeed, the US Food and Drug Administration sets a labeling value for dietary fiber based on the IOM AI for this ingredient. This conference explores the definitions, concepts, and data on two of the best examples of bioactive substances that, perhaps, should have NRVs: lutein and zeaxanthin, and n-3 long-chain polyunsaturated fatty acids.


Assuntos
Dieta , Ácidos Graxos Ômega-3 , Luteína , Política Nutricional , Xantofilas , Encéfalo/fisiologia , Carotenoides , Criança , Alimentos , Rotulagem de Alimentos , Promoção da Saúde , Humanos , Degeneração Macular/prevenção & controle , Necessidades Nutricionais , Valores de Referência , Estados Unidos , Visão Ocular , Zeaxantinas
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