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1.
Nutrients ; 13(10)2021 Sep 24.
Artigo em Inglês | MEDLINE | ID: mdl-34684356

RESUMO

BACKGROUND: Carotenoids and docosahexaenoic acid (DHA) were identified as essential components for eye health and are both naturally present in eggs. OBJECTIVE: We aimed to evaluate the effect of the daily consumption of two eggs enriched with lutein/zeaxanthin and DHA on macular pigment optical density (MPOD) and on circulating xanthophyll and fatty acid concentrations in healthy participants. METHODS: Ninety-nine healthy volunteers consumed either two standard eggs or two enriched eggs per day for 4 months. MPOD was measured at baseline (V0) and at follow-up (V4) using a modified confocal scanning laser ophthalmoscope (primary outcome). Blood samples were collected to determine total plasma and lipoprotein fatty acids and lutein/zeaxanthin compositions at V0 and V4 (secondary outcomes). RESULTS: A slight but significant increase in MPOD was observed for all study participants consuming two eggs per day for 4 months at all eccentricities (0.5°, 1°, 2°, and 4°). Plasma and lipoprotein lutein, zeaxanthin, and DHA concentrations significantly increased in both groups but were greater in the enriched group (for the enriched group (V0 vs. V4): lutein, 167 vs. 369 ng/mL; zeaxanthin, 17.7 vs. 29.2 ng/mL; DHA, 1.89 vs. 2.56% of total fatty acids). Interestingly, lutein from high-density lipoprotein (HDL) was strongly correlated with MPOD at 0.5 and 1° eccentricities (rho = 0.385, p = 0.008, and rho = 0.461, p = 0.001, respectively). CONCLUSIONS: MPOD was slightly increased in both groups. Lutein, zeaxanthin, and DHA plasma concentrations were strongly enhanced in the enriched group compared with the standard group. A significant correlation was found between MPOD level and lutein concentration in HDL.


Assuntos
Ácidos Docosa-Hexaenoicos/sangue , Alimentos Fortificados , Luteína/sangue , Pigmento Macular/sangue , Adulto , Eritrócitos/metabolismo , Feminino , Humanos , Lipoproteínas/sangue , Masculino , Fenômenos Ópticos , Cooperação do Paciente , Xantofilas/sangue , Adulto Jovem , Zeaxantinas/sangue
2.
Nutrients ; 13(10)2021 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-34684614

RESUMO

Lutein is mainly supplied by dietary fruit and vegetables, and they are commonly jointly assessed in observational and interventional studies. Lutein bioavailability and health benefits depend on the food matrix. This study aimed to assess the effect of dietary intervention with lutein-rich fruit or vegetables on lutein status markers, including serum and faecal concentrations (by high pressure liquid chromatography), dietary intake (24 h recalls ×3), and macular pigment optical density (MPOD) and contrast threshold (CT) as visual outcomes. Twenty-nine healthy normolipemic subjects, aged 45-65 y, consumed 1.8 mg lutein/day supplied from fruits (14 subjects, 500 g/day of oranges, kiwi and avocados) or vegetables (15 subjects, 180 g/day of green beans, pumpkin, and sweet corn) for four weeks. Serum lutein concentration increased by 37%. The effect of the food group intervention was statistically significant for serum lutein+zeaxanthin concentration (p = 0.049). Serum α- and ß-carotene were influenced by food type (p = 0.008 and p = 0.005, respectively), but not by time. Serum lutein/HDL-cholesterol level increased by 29% (total sample, p = 0.008). Lutein+zeaxanthin/HDL-cholesterol increased, and the intervention time and food group eaten had an effect (p = 0.024 and p = 0.010, respectively) which was higher in the vegetable group. The MPOD did not show variations, nor did it correlate with CT. According to correlation matrixes, serum lutein was mainly related to lutein+zeaxanthin expressed in relation to lipids, and MPOD with the vegetable group. In faecal samples, only lutein levels increased (p = 0.012). This study shows that a relatively low amount of lutein, supplied by fruit or vegetables, can have different responses in correlated status markers, and that a longer intervention period is needed to increase the MPOD. Therefore, further study with larger sample sizes is needed on the different responses in the lutein status markers and on food types and consumption patterns in the diet, and when lutein in a "pharmacological dose" is not taken to reduce a specific risk.


Assuntos
Fezes/química , Frutas/química , Luteína/sangue , Pigmento Macular/sangue , Verduras/química , Biomarcadores/sangue , Carotenoides/sangue , Dieta , Análise Fatorial , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Análise de Componente Principal , Zeaxantinas/sangue
3.
Vestn Oftalmol ; 137(5. Vyp. 2): 262-267, 2021.
Artigo em Russo | MEDLINE | ID: mdl-34669336

RESUMO

The non-exudative form of age-related macular degeneration (AMD) is a disease with long-term progression for which effective treatments have not been found. Many studies are being conducted to find effective drugs to prevent the appearance of drusen and increase in RPE atrophy area, which could help avoid this more dangerous form of AMD. The main drugs (nutraceuticals) that are used to treat the dry form of AMD are lutein, zeaxanthin and omega-3 fatty acids. Additionally, treatment may include nanosecond laser therapy for drusen in advanced AMD, panretinal subthreshold micropulse laser exposure for atrophic AMD, as well as microcurrent stimulation. Further research in this area should be aimed at understanding all the pathogenetic mechanisms associated with the development of AMD, and developing new approaches to the treatment of this disease including physiotherapy.


Assuntos
Atrofia Geográfica , Degeneração Macular , Drusas Retinianas , Progressão da Doença , Humanos , Luteína , Degeneração Macular/terapia , Zeaxantinas
4.
Nutrients ; 13(9)2021 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-34579116

RESUMO

Lutein is a dietary carotenoid preferentially accumulated in the eye and the brain in early life and throughout the life span. Lutein accumulation in areas of high metabolism and oxidative stress such as the eye and the brain suggest a unique role of this ingredient during the development and maturation of these organs of common embryological origin. Lutein is naturally provided to the developing baby via the cord blood, breast milk and then infant diet. The presence of this carotenoid depends on fruit and vegetable intakes and its bioavailability is higher in breastmilk. This paper aims to review the anatomical development of the eye and the brain, explore the presence and selective deposition of lutein in these organs during pregnancy and infancy and, based on its functional characteristics, present the latest available research on the beneficial role of lutein in the pediatric population. The potential effects of lutein in ameliorating conditions associated with increase oxidative stress such as in prematurity will be also addressed. Since consumption of lutein rich foods falls short of government guidelines and in most region of the world infant formulas lack this bioactive, dietary recommendations for pregnant and breastfeeding women and their child can help to bridge the gap.


Assuntos
Encéfalo/crescimento & desenvolvimento , Olho/crescimento & desenvolvimento , Luteína/administração & dosagem , Adolescente , Adulto , Encéfalo/metabolismo , Aleitamento Materno/métodos , Carotenoides/administração & dosagem , Carotenoides/metabolismo , Criança , Pré-Escolar , Dieta/métodos , Olho/metabolismo , Feminino , Frutas/química , Humanos , Lactente , Fórmulas Infantis/química , Luteína/metabolismo , Masculino , Leite Humano/química , Estresse Oxidativo , Gravidez , Xantofilas/metabolismo , Adulto Jovem , Zeaxantinas/metabolismo
5.
J Agric Food Chem ; 69(39): 11626-11636, 2021 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-34554747

RESUMO

Crocetin, a high-value apocarotenoid in saffron, is widely applied to the fields of food and medicine. However, the existing method of obtaining crocetin through large-scale cultivation is far from meeting the market demand. Microbial synthesis of crocetin is a potential alternative to traditional resources, and it is found that carotenoid cleavage dioxygenase (CCD) is the critical enzyme to synthesize crocetin. So, in this study, we used "hybrid-tunnel" engineering to obtain variants of Crocus sativus-derived CsCCD2, essential for zeaxanthin conversion into crocetin, with a broader substrate specificity and higher catalytic efficiency. Variants including S323A, with a lower charge bias and a larger tunnel size than the wild-type, showed a 5-fold higher crocetin titer in yeast-based fermentations. S323A could also convert the ß-carotene substrate to crocetin dialdehyde and exhibited a 12.83-fold greater catalytic efficiency (kcat/Km) toward zeaxanthin than the wild-type in vitro. This strategy enabled the production of 107 mg/L crocetin in 5 L fed-batch fermentation, higher than that previously reported. Our findings demonstrate that engineering access tunnels to expand the substrate profile by in silico protein design represents a viable strategy to refine the catalytic properties of enzymes across a range of applications.


Assuntos
Crocus , Dioxigenases , Carotenoides , Vitamina A/análogos & derivados , Zeaxantinas
6.
Nutrients ; 13(9)2021 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-34579067

RESUMO

Twilight and low luminance levels are visually challenging environments for the elderly, especially when driving at night. Carotenoid rich diets are known to increase macular pigment optical density (MPOD), which in turn leads to an improvement in visual function. It is not known whether augmenting MPOD can lead to a decrease in vision related night driving difficulties. Additionally, it is unknown if carotenoid supplementation provides additional measurable benefits to one's useful field of view (UFOV) along with a decreased composite crash risk score. The aim of the study was to evaluate changes in night vision function and UFOV in individuals that took carotenoid vitamin supplements for a six-month period compared to a placebo group. METHODS: A prospective, randomized, double-blind, six-month trial of a 14 mg zeaxanthin/7 mg lutein-based supplement was carried out. Participants were randomized into active or placebo group (approx 2:1). RESULTS: n = 33 participants (26 males/7 females) participated with 93% capsule intake compliance in the supplemented group (n = 24) and placebo group (n = 9). MPOD (mean/standard error SE) in the active group increased in the Right eye from 0.35 density units (du)/0.04 SE to 0.41 du/0.05 SE; p < 0.001 and in the Left eye from 0.35 du/0.05 SE to 0.37 du, p > 0.05). The supplemented group showed significant improvements in contrast sensitivity with glare in both eyes with improvements in LogMAR scores of 0.147 and 0.149, respectively (p = 0.02 and 0.01, respectively), monocularly tested glare recovery time improved 2.76 and 2.54 s, respectively, (p = 0.008 and p = 0.02), and we also noted a decreased preferred luminance required to complete visual tasks (p = 0.02 and 0.03). Improvements in UFOV scores of divided attention (p < 0.001) and improved composite crash risk score (p = 0.004) were seen in the supplemented group. The placebo group remained unchanged. CONCLUSIONS: The NVC demonstrates that augmenting MPOD in individuals with difficulty in night vision showed measurable benefits in numerous visual functions that are important for night vision driving in this small sample RCT. Additionally, we observed an improvement in UFOV divided attention test scores and decreased composite risk scores.


Assuntos
Suplementos Nutricionais , Luteína/farmacologia , Pigmento Macular/metabolismo , Visão Noturna/efeitos dos fármacos , Visão Ocular/efeitos dos fármacos , Acuidade Visual/efeitos dos fármacos , Zeaxantinas/farmacologia , Acidentes de Trânsito/prevenção & controle , Idoso , Condução de Veículo , Método Duplo-Cego , Feminino , Humanos , Macula Lutea/efeitos dos fármacos , Macula Lutea/metabolismo , Degeneração Macular , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Testes de Campo Visual
7.
Nutrients ; 13(8)2021 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-34444721

RESUMO

The study was designed to: (1) Analyze and create protocols of obtaining measurements using the Macular Pigment Reflectometry (MPR). (2) To assess the agreement of MPOD measurements obtained using the heterochromatic flicker photometry (MPS II) and MPR. (3) To obtain the lutein and zeaxanthin optical density obtained using the MPR in the central one-degree of the macula. The measurements were performed using the MPR and heterochromatic flicker photometry. The MPR measurements were performed twice without pupillary dilation and twice following pupillary dilation. The MPR measurements were performed for a 40-s period and the spectrometer signal was parsed at different time points: 10-20, 10-30, 10-40, 20-30, 20-40, and 30-40 s. The MPR analyzes the high-resolution spectrometer signal and calculates MPOD, lutein optical density and zeaxanthin optical density automatically. The MPR-MPOD data was compared with MPPS II-MPOD results. The MPR-MPOD values are highly correlated and in good agreement with the MPS II-MPOD. Of the various parsing of the data, the data 10-30 interval was the best at obtaining the MPOD, lutein, and zeaxanthin values (8-12% coefficient of repeatability). The lutein to zeaxanthin ratio in the central one-degree of the macula was 1:2.40. Dilation was not needed to obtain the MPOD values but provided better repeatability of lutein and zeaxanthin optical density. MPR generates MPOD measurements that is in good agreement with MPS II. The device can produce lutein and zeaxanthin optical density which is not available from other clinical devices.


Assuntos
Técnicas de Diagnóstico Oftalmológico , Luteína/análise , Macula Lutea/química , Pigmento Macular/análise , Adulto , Protocolos Clínicos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fotometria , Reprodutibilidade dos Testes , Adulto Jovem , Zeaxantinas/análise
8.
Appl Microbiol Biotechnol ; 105(16-17): 6133-6142, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34338805

RESUMO

Violaxanthin is biosynthesized from zeaxanthin with zeaxanthin epoxidase (ZEP) by way of antheraxanthin only in photosynthetic eukaryotes including higher plants and involved in the xanthophyll cycle to eliminate excessive light energy. Violaxanthin and antheraxanthin have commercially been unavailable, in contrast to commercial production of other carotenoids contained in higher plants, e.g., lycopene, ß-carotene, lutein, zeaxanthin, ß-cryptoxanthin, and capsanthin. One of the reasons is considered that resource plants or other resource organisms do not exist for enabling efficient supply of the epoxy-carotenoids, which are expected to be produced through (metabolic) pathway engineering with heterologous microbial hosts such as Escherichia coli and Saccharomyces cerevisiae. In this Mini-Review, we show heterologous production of violaxanthin with the two microorganisms that have exhibited significant advances these days. We further describe natural function and occurrence, and biosynthesis involving violaxanthin, antheraxanthin, and their derivatives that include auroxanthin and mutatoxanthin. KEY POINTS: • A comprehensive review on epoxy-carotenoids violaxanthin and antheraxanthin. • Pathway engineering for the epoxy-carotenoids in heterologous microbes. • Our new findings on violaxanthin production with the budding yeast.


Assuntos
Luteína , Xantofilas , Carotenoides , Zeaxantinas
9.
Molecules ; 26(15)2021 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-34361748

RESUMO

The aim of this study was to determine the effects that the type of impregnating solution and drying method (freeze drying (FD) and vacuum drying (VD) at 45 °C and convective drying (CD) at 50, 60, and 70 °C) had on the physicochemical and quality properties of courgettes. Courgette slices were vacuum-impregnated (6 kPa) in freshly squeezed onion, kale, and onion and kale (50:50) juices with 3% NaCl solution (N). The application of vacuum impregnation (VI) with impregnating solutions from freshly squeezed onions and kale had a beneficial effect on the bioactive values of courgette. The highest contents of quercetin (41.84 µg/g d.m.) and carotenoids (276.04 µg/g d.m.) were found in courgette impregnated with onion juice after freeze drying. The highest values of lutein and zeaxanthin (216.42 µg/g d.m.) were recorded for courgette impregnated with kale juice and convective dried. By analysing the kinetics of convective drying, the best matching of the logistic model was found. Increasing the drying process temperature from 50 to 70 °C reduced the drying time from 15% to 36%, depending on the type of impregnating solution used. Water activity < 0.6 was recorded for courgette dried by freezing, vacuum, and convection at 60 and 70 °C. Conclusions: The vacuum impregnation process and the impregnation solutions from freshly squeezed vegetables can be used to develop new snacks with high levels of bioactive compounds. The FD method is the most appropriate considering both the bioactive compounds content and the obtained colour and water activity.


Assuntos
Antioxidantes/análise , Cucurbitaceae/química , Dessecação/métodos , Tecnologia de Alimentos/métodos , Liofilização/métodos , Brassica/química , Carotenoides/análise , Dessecação/instrumentação , Liofilização/instrumentação , Humanos , Cinética , Luteína/análise , Valor Nutritivo , Cebolas/química , Quercetina/análise , Lanches , Vácuo , Zeaxantinas/análise
10.
Nutrients ; 13(7)2021 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-34371951

RESUMO

Diabetic retinopathy, which was primarily regarded as a microvascular disease, is the leading cause of irreversible blindness worldwide. With obesity at epidemic proportions, diabetes-related ocular problems are exponentially increasing in the developed world. Oxidative stress due to hyperglycemic states and its associated inflammation is one of the pathological mechanisms which leads to depletion of endogenous antioxidants in retina in a diabetic patient. This contributes to a cascade of events that finally leads to retinal neurodegeneration and irreversible vision loss. The xanthophylls lutein and zeaxanthin are known to promote retinal health, improve visual function in retinal diseases such as age-related macular degeneration that has oxidative damage central in its etiopathogenesis. Thus, it can be hypothesized that dietary supplements with xanthophylls that are potent antioxidants may regenerate the compromised antioxidant capacity as a consequence of the diabetic state, therefore ultimately promoting retinal health and visual improvement. We performed a comprehensive literature review of the National Library of Medicine and Web of Science databases, resulting in 341 publications meeting search criteria, of which, 18 were found eligible for inclusion in this review. Lutein and zeaxanthin demonstrated significant protection against capillary cell degeneration and hyperglycemia-induced changes in retinal vasculature. Observational studies indicate that depletion of xanthophyll carotenoids in the macula may represent a novel feature of DR, specifically in patients with type 2 or poorly managed type 1 diabetes. Meanwhile, early interventional trials with dietary carotenoid supplementation show promise in improving their levels in serum and macular pigments concomitant with benefits in visual performance. These findings provide a strong molecular basis and a line of evidence that suggests carotenoid vitamin therapy may offer enhanced neuroprotective effects with therapeutic potential to function as an adjunct nutraceutical strategy for management of diabetic retinopathy.


Assuntos
Carotenoides/uso terapêutico , Retinopatia Diabética/dietoterapia , Suplementos Nutricionais , Luteína/uso terapêutico , Zeaxantinas/uso terapêutico , Animais , Antioxidantes/farmacologia , Antioxidantes/uso terapêutico , Carotenoides/farmacologia , Humanos , Luteína/farmacologia , Pigmento Macular/análise , Zeaxantinas/farmacologia
11.
Nutrients ; 13(6)2021 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-34204051

RESUMO

Primary open-angle glaucoma (POAG) remains a leading cause of irreversible blindness globally. Recent evidence further substantiates sustained oxidative stress, and compromised antioxidant defenses are key drivers in the onset of glaucomatous neurodegeneration. Overwhelming oxidative injury is likely attributed to compounding mitochondrial dysfunction that worsens with age-related processes, causing aberrant formation of free radical species. Thus, a compromised systemic antioxidant capacity exacerbates further oxidative insult in glaucoma, leading to apoptosis, neuroinflammation, and subsequent tissue injury. The purpose of this systematic review is to investigate the neuroprotective benefits of the macular carotenoids lutein, zeaxanthin, and meso-zeaxanthin on glaucomatous neurodegeneration for the purpose of adjunctive nutraceutical treatment in glaucoma. A comprehensive literature search was conducted in three databases (PubMed, Cochrane Library, and Web of Science) and 20 records were identified for screening. Lutein demonstrated enhanced neuroprotection on retinal ganglion cell survival and preserved synaptic activity. In clinical studies, a protective trend was seen with greater dietary consumption of carotenoids and risk of glaucoma, while greater carotenoid levels in macular pigment were largely associated with improved visual performance in glaucomatous eyes. The data suggest that carotenoid vitamin therapy exerts synergic neuroprotective benefits and has the capacity to serve adjunctive therapy in the management of glaucoma.


Assuntos
Antioxidantes/administração & dosagem , Carotenoides/administração & dosagem , Suplementos Nutricionais , Glaucoma de Ângulo Aberto/terapia , Glaucoma de Ângulo Aberto/metabolismo , Humanos , Luteína/administração & dosagem , Pigmento Macular/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Acuidade Visual/efeitos dos fármacos , Zeaxantinas/administração & dosagem
12.
Nutrients ; 13(6)2021 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-34203817

RESUMO

Lutein and zeaxanthin may lower the risk of age-related macular degeneration (AMD). We evaluated the associations of plasma lutein and zeaxanthin with the incidence of advanced AMD in the Alienor study (Antioxydants Lipides Essentiels Nutrition et Maladies Oculaires). Alienor study is a prospective population-based cohort of 963 residents of Bordeaux, France, who were 73 years or older at baseline (2006-2008). The present study included 609 participants with complete ophthalmologic and plasma carotenoids data. Examinations were performed every two years over an eight-year period (2006 to 2017). Plasma lutein and zeaxanthin were determined at baseline from fasting blood samples using high-performance liquid chromatography. Cox proportional hazard models were used to assess associations between plasma lutein, zeaxanthin, and their (total cholesterol (TC) + triglycerides (TG)) ratios with AMD. Among the 609 included participants, 54 developed advanced incident AMD during a median follow-up time of 7.6 years (range 0.7 to 10.4). Participants with higher plasma lutein had a reduced risk for incident advanced AMD in the fully adjusted model (HR = 0.63 per 1-SD increase (95% CI, 0.41-0.97), p = 0.03). A similar association was observed using the lutein/(TC + TG) ratio (HR = 0.59 (95% CI, 0.39-0.90), p = 0.01). No associations were evidenced for other carotenoids. Higher plasma lutein was associated with a 37% reduced risk of incident advanced AMD.


Assuntos
Biomarcadores/sangue , Luteína/sangue , Degeneração Macular/sangue , Degeneração Macular/epidemiologia , Idoso , Idoso de 80 Anos ou mais , Carotenoides/sangue , Colesterol/sangue , Estudos de Coortes , Feminino , França , Humanos , Incidência , Modelos Logísticos , Masculino , Estado Nutricional , Estudos Prospectivos , Fatores de Risco , Triglicerídeos , Zeaxantinas/sangue
13.
J Alzheimers Dis ; 82(3): 1055-1066, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34151808

RESUMO

BACKGROUND: Multiple lines of evidence indicate protective effects of carotenoids in Alzheimer's disease (AD). However, previous epidemiological studies reported inconsistent results regarding the associations between carotenoids levels and the risk of AD. OBJECTIVE: Our study aims to evaluate the associations of six major members of carotenoids with the occurrence of AD by conducting a systematic review and meta-analysis. METHODS: Following PRISMA guidelines, a comprehensive literature search of PubMed, Web of Science, Ebsco, and PsycINFO databases was conducted, and the quality of each included studies was evaluated by a validated scoring systems. Standardized mean differences (SMD) with 95% confidence intervals (CI) were determined by using a random effects model. Heterogeneity was evaluated by I2 statistics. Publication bias was detected using funnel plots and Egger's test. RESULTS: Sixteen studies, with 10,633 participants were included. Pooled analysis showed significantly lower plasma/serum levels of lutein (SMD = -0.86, 95% CI: -1.67 to -0.05, p = 0.04) and zeaxanthin (SMD = -0.59; 95% CI: -1.12 to -0.06, p = 0.03) in patients with AD versus cognitively intact controls, while α-carotene (SMD = 0.21, 95% CI: -0.68 to 0.26, p = 0.39), ß-carotene (SMD = 0.04, 95% CI: -0.57 to 0.65, p = 0.9), lycopene (SMD = -0.12, 95% CI: -0.96 to 0.72, p = 0.78), and ß-cryptoxanthin (SMD = -0.09, 95% CI: -0.83 to 0.65, p = 0.81) did not achieve significant differences. CONCLUSION: Of six major members of carotenoids, only lutein and zeaxanthin concentrations in plasma/serum were inversely related to the risk of AD. More high-quality longitudinal studies are needed to verify these findings.


Assuntos
Doença de Alzheimer/sangue , Doença de Alzheimer/diagnóstico , Carotenoides/sangue , Biomarcadores/sangue , Estudos de Casos e Controles , Humanos , Licopeno/sangue , Zeaxantinas/sangue , beta Caroteno/sangue
14.
Nutr Res ; 91: 36-43, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-34134039

RESUMO

Lutein exhibits effective antioxidant activity conferring protective action against oxidative stress in age-related macular degeneration and cognitive decline. The inability to synthesize these compounds by the human body and the necessity to combat day-to-day oxidative stress prioritizes daily consumption of lutein. However, the bioavailability of the orally consumed lutein largely depends on its gastrointestinal absorption and subsequent metabolism which is in turn governed by various intrinsic and extrinsic factors. One of the most important yet least studied factors is the genetic make-up of an individual. The proteins that partake in the absorption, transportation, metabolism and excretion of lutein are encoded by the genes that experience inter-individual variability. Reports suggest that the unanimous effect of phenotypes resulting from such inter-individual variability in the genes of interest causes modulation of lutein bioavailability which is discussed in detail in this review article. However, despite the available reports, a community-based approach to a larger population is required to obtain a stronger understanding of the relationship between inter-individual variability among these genes and lutein bioavailability. Such an understanding of nutrigenetics could not only pave a way to decipher mechanisms that modulate lutein bioavailability but also help in setting the dosage requirements of each patient.


Assuntos
Variação Genética , Luteína/farmacocinética , Zeaxantinas/metabolismo , Disponibilidade Biológica , Humanos , Absorção Intestinal , Luteína/metabolismo , Fenótipo
15.
Adv Nutr ; 12(4): 1087-1099, 2021 07 30.
Artigo em Inglês | MEDLINE | ID: mdl-33962461

RESUMO

Dietary bioactives are food substances that promote health but are not essential to prevent typical deficiency conditions. Examples include lutein and zeaxanthin, omega-3 fatty acids, and flavonoids. When quality evidence is available, quantified intake recommendations linking dietary bioactives with specific health benefits will enable health professionals to provide evidence-based information to consumers. Without evidence-based recommendations, consumers use information from available sources that often lack standards and rigor. This article describes a framework to develop guidance based on quality evidence fully vetted for efficacy and safety by qualified experts, and designed to communicate the amounts of specific dietary bioactive compounds with identified health benefits. The 4-step Framework described here can be adapted by credible health organizations to work within their guideline development process. Standards of practice used in clinical guidelines are adapted to quantify dietary bioactive intake recommendations from foods consumed by the general public, by taking into account that side effects and trade-offs are often needed for medical treatments but are not acceptable for dietary bioactives. In quantifying dietary bioactive recommendations, this Framework establishes 4 decision-making steps: 1) characterize the bioactive, determine amounts in specific food sources, and quantify intakes; 2) evaluate safety; 3) quantify the causal relation between the specific bioactive and accepted markers of health or normal function via systematic evidence reviews; and 4) translate the evidence into a quantified bioactive intake statement. This Framework provides a working model that can be updated as new approaches are advanced.


Assuntos
Dieta , Promoção da Saúde , Alimentos , Humanos , Luteína , Zeaxantinas
16.
Transl Vis Sci Technol ; 10(2): 18, 2021 02 05.
Artigo em Inglês | MEDLINE | ID: mdl-34003903

RESUMO

Purpose: Measurements of macular pigment optical density (MPOD) by the autofluorescence technique yield underestimations of actual values in eyes with cataract. We applied deep learning (DL) to correct this error. Subjects and Methods: MPOD was measured by SPECTRALIS (Heidelberg Engineering, Heidelberg, Germany) in 197 eyes before and after cataract surgery. The nominal MPOD values (= preoperative value) were corrected by three methods: the regression equation (RE) method, subjective classification (SC) method (described in our previous study), and DL method. The errors between the corrected and true values (= postoperative value) were calculated for local MPODs at 0.25°, 0.5°, 1°, and 2° eccentricities and macular pigment optical volume (MPOV) within 9° eccentricity. Results: The mean error for MPODs at four eccentricities was 32% without any correction, 15% with correction by RE, 16% with correction by SC, and 14% with correction by DL. The mean error for MPOV was 21% without correction and 14%, 10%, and 10%, respectively, with correction by the same methods. The errors with any correction were significantly lower than those without correction (P < 0.001, linear mixed model with Tukey's test). The errors with DL correction were significantly lower than those with RE correction in MPOD at 1° eccentricity and MPOV (P < 0.001) and were equivalent to those with SC correction. Conclusions: The objective method using DL was useful to correct MPOD values measured in aged people. Translational Relevance: MPOD can be obtained with small errors in eyes with cataract using DL.


Assuntos
Catarata , Aprendizado Profundo , Pigmento Macular , Idoso , Alemanha , Humanos , Luteína , Zeaxantinas
17.
PLoS One ; 16(5): e0251324, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34043644

RESUMO

INTRODUCTION: The dietary carotenoids lutein (L) and zeaxanthin (Z) are transported in the bloodstream by lipoproteins, sequestered by adipose tissue, and eventually captured in the retina where they constitute macular pigment. There are no L&Z dietary intake recommendations nor desired blood/tissue concentrations for the Spanish general population. Our aim was to assess the correlation of L&Z habitual dietary intake (excluding food supplements), resulting serum concentrations and lipid profile with macular pigment optical density (MPOD) as well as the contrast sensitivity (CT), as visual outcome in normolipemic subjects (n = 101) aged 45-65. METHODS: MPOD was measured by heterochromatic flicker photometry, serum L&Z by HPLC, the dietary intake by a 3-day food records and CT using the CGT-1000-Contrast-Glaretester at six stimulus sizes, with and without glare. RESULTS: Lutein and zeaxanthin concentrations (median) in serum: 0.361 and 0.078 µmol/L, in dietary intake: 1.1 mg L+Z/day. MPOD: 0.34du. L+Z intake correlates with their serum concentrations (rho = 0.333, p = 0.001), which in turn correlates with MPOD (rho = 0.229, p = 0.000) and with fruit and vegetable consumption (rho = 0.202, p = 0.001), but not with lutein+zeaxanthin dietary intake. MPOD correlated with CT, with and without glare (rho ranges: -0.135, 0.160 and -0.121, -0.205, respectively). MPOD predictors: serum L+Z, L+Z/HDL-cholesterol (ß-coeficient: -0.91±0.2, 95%CI: -1.3,-0.5) and HDL-cholesterol (R2 = 15.9%). CT predictors: MPOD, mainly at medium and smaller visual angles (corresponding to spatial frequencies for which sensitivity declines with age) and gender (ß-coefficients ranges: -0.95,-0.39 and -0.13,-0.39, respectively). CONCLUSION: A higher MPOD is associated with a lower ratio of L+Z/HDL-cholesterol and with a lower CT (higher contrast sensitivity). The HDL-cholesterol would also act indirectly on the CT improving the visual function.


Assuntos
Sensibilidades de Contraste/efeitos dos fármacos , Ingestão de Alimentos/fisiologia , Pigmento Macular/metabolismo , HDL-Colesterol/metabolismo , Dieta , Suplementos Nutricionais , Feminino , Ofuscação , Voluntários Saudáveis , Humanos , Lipídeos/sangue , Lipoproteínas/metabolismo , Luteína/administração & dosagem , Macula Lutea/efeitos dos fármacos , Macula Lutea/metabolismo , Masculino , Pessoa de Meia-Idade , Retina/efeitos dos fármacos , Retina/metabolismo , Visão Ocular/efeitos dos fármacos , Zeaxantinas/administração & dosagem
18.
Adv Nutr ; 12(5): 1723-1733, 2021 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-33979433

RESUMO

Previous meta-analysis studies have indicated inverse associations between some carotenoids and risks of metabolic syndrome, cardiovascular disease, cancer, and all-cause mortality. However, the results for associations between carotenoids and type 2 diabetes (T2D) remain inconsistent and no systematic assessment has been done on this topic. We conducted a systematic review and meta-analysis to examine the associations of dietary intakes and circulating concentrations of carotenoids with risk of T2D. We searched PubMed and Ovid Embase from database inception to July 2020. Prospective observational studies of carotenoids and T2D risk were included. Random-effects models were used to summarize the RRs and 95% CIs. Thirteen publications were included. Dietary intake of ß-carotene was inversely associated with the risk of T2D, and the pooled RR comparing the highest with the lowest categories was 0.78 (95% CI: 0.70, 0.87; I2 = 13.7%; n = 6); inverse associations were also found for total carotenoids (n = 2), α-carotene (n = 4), and lutein/zeaxanthin (n = 4), with pooled RRs ranging from 0.80 to 0.91, whereas no significant associations were observed for ß-cryptoxanthin and lycopene. Circulating concentration of ß-carotene was associated with a lower risk of T2D, and the pooled RR comparing extreme categories was 0.60 (95% CI: 0.46, 0.78; I2 = 56.2%; n = 7); inverse associations were also found for total carotenoids (n = 3), lycopene (n = 4), and lutein (n = 2), with pooled RRs ranging from 0.63 to 0.85, whereas no significant association was found for circulating concentrations of α-carotene and zeaxanthin when comparing extreme categories. Dose-response analysis indicated that nonlinear relations were observed for circulating concentrations of α-carotene, ß-carotene, lutein, and total carotenoids (all P-nonlinearity < 0.05), but not for other carotenoids or dietary exposures. In conclusion, higher dietary intakes and circulating concentrations of total carotenoids, especially ß-carotene, were associated with a lower risk of T2D. More studies are needed to confirm the causality and explore the role of foods rich in carotenoids in prevention of T2D. This systematic review was registered at www.crd.york.ac.uk/prospero as CRD42020196616.


Assuntos
Diabetes Mellitus Tipo 2 , Carotenoides , Ingestão de Alimentos , Humanos , Luteína , Estudos Observacionais como Assunto , Fatores de Risco , Zeaxantinas
19.
Trials ; 22(1): 300, 2021 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-33888136

RESUMO

BACKGROUND: Lutein (L), zeaxanthin (Z), and meso-zeaxanthin (MZ), collectively called the macular pigment (MP), are dietary carotenoids that preferentially localize in the macula of the human eye. MP protects the macula from photo-oxidative damage and enhances visual function. Inadequate maternal intake of carotenoids, coupled with the placental transfer of maternal carotenoids to support fetal brain and retina development, potentially put mothers at risk of depletion systemically and in their ocular tissues. Presently, maternal carotenoid status throughout pregnancy remains poorly characterized, and no prospective randomized controlled trial of L and Z supplementation via prenatal vitamins has assessed maternal and infants' systemic and ocular carotenoid status during pregnancy. We hypothesize that prenatal maternal carotenoid supplementation will counteract maternal carotenoid depletion during pregnancy and will improve biomarkers of carotenoid status of both mothers and infants. METHODS: Lutein and Zeaxanthin in Pregnancy (L-ZIP) is a phase 2, single-center, prospective, double-masked, randomized active-controlled clinical trial conducted at the John A. Moran Eye Center, University of Utah, Salt Lake City, UT, USA. Participants consume a daily standard prenatal multivitamin with no added carotenoids and are randomized (1:1 allocation) to receive either a capsule containing 10 mg L and 2 mg Z in safflower oil (Carotenoid group) or a capsule containing only safflower oil with no added carotenoids (Control group) for a period of 6 to 8 months. Skin, serum, and ocular carotenoids are measured at every study visit (i.e., within the first trimester [baseline], second trimester, third trimester, and 0-2 weeks postpartum). Skin carotenoid assessment is by resonance Raman spectroscopy (RRS); serum carotenoid status is quantified using high-performance liquid chromatography (HPLC); and MP is measured with the dual-wavelength autofluorescence. Infants' MP and foveal anatomy are assessed using RetCam retinal camera and Bioptigen SD-OCT, respectively. The primary outcomes are changes in maternal systemic and ocular carotenoid status during pregnancy. DISCUSSION: L-ZIP is the first prospective RCT to investigate maternal carotenoid status throughout pregnancy and to determine whether prenatal maternal carotenoid supplementation will offset maternal carotenoid depletion and improve biomarkers of maternal and infant's carotenoid status. Findings from L-ZIP will strengthen recommendations regarding prenatal carotenoid supplementation and consequently inform policy decisions. TRIAL REGISTRATION: ClinicalTrials.gov NCT03750968 . Registered on November 23, 2018.


Assuntos
Luteína , Placenta , Suplementos Nutricionais , Feminino , Humanos , Gravidez , Estudos Prospectivos , Ensaios Clínicos Controlados Aleatórios como Assunto , Zeaxantinas
20.
Int J Mol Sci ; 22(6)2021 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-33804002

RESUMO

Antenna protein aggregation is one of the principal mechanisms considered effective in protecting phototrophs against high light damage. Commonly, it is induced, in vitro, by decreasing detergent concentration and pH of a solution of purified antennas; the resulting reduction in fluorescence emission is considered to be representative of non-photochemical quenching in vivo. However, little is known about the actual size and organization of antenna particles formed by this means, and hence the physiological relevance of this experimental approach is questionable. Here, a quasi-single molecule method, fluorescence correlation spectroscopy (FCS), was applied during in vitro quenching of LHCII trimers from higher plants for a parallel estimation of particle size, fluorescence, and antenna cluster homogeneity in a single measurement. FCS revealed that, below detergent critical micelle concentration, low pH promoted the formation of large protein oligomers of sizes up to micrometers, and therefore is apparently incompatible with thylakoid membranes. In contrast, LHCII clusters formed at high pH were smaller and homogenous, and yet still capable of efficient quenching. The results altogether set the physiological validity limits of in vitro quenching experiments. Our data also support the idea that the small, moderately quenching LHCII oligomers found at high pH could be relevant with respect to non-photochemical quenching in vivo.


Assuntos
Proteína do Homeodomínio de Antennapedia/genética , Complexos de Proteínas Captadores de Luz/genética , Processos Fototróficos/genética , Agregados Proteicos/genética , Proteína do Homeodomínio de Antennapedia/química , Clorofila/química , Clorofila/genética , Clorofila/efeitos da radiação , Análise por Conglomerados , Fluorescência , Concentração de Íons de Hidrogênio , Luz/efeitos adversos , Complexos de Proteínas Captadores de Luz/química , Fotossíntese/genética , Complexo de Proteína do Fotossistema II/genética , Complexo de Proteína do Fotossistema II/efeitos da radiação , Espectrometria de Fluorescência , Tilacoides/química , Tilacoides/genética , Tilacoides/efeitos da radiação , Zeaxantinas/genética
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