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Purpose Lutein and zeaxanthin are macular pigments with a protective function in the retina. These xanthophylls must be obtained from the diet or added to foods or supplements via easy-to-use, stable formulations. The technique employed to produce these formulations may affect the bioavailability of the xanthophylls. Methods Forty-eight healthy volunteers were randomized into this double-blind, cross-over study investigating the plasma kinetics of lutein provided as two different beadlet formulations. Subjects ( n  = 48) received a single dose of 20 mg of lutein as either a starch-matrix (“SMB”, FloraGLO ® Lutein 5 %) or as a cross-linked alginate-matrix beadlet (“AMB”, Lyc-O-Lutein 20 %) formulation. Plasma concentrations of lutein and zeaxanthin were measured at 0, 1, 3, 6, 9, 12, 14, 24, 26, 28, 32, 36, 48, 72, 168, and 672 h. Results The mean plasma AUC (0–72h) , AUC (0–672h) , and C max for total lutein and zeaxanthin and their all - E -isomers were significantly increased ( p  < 0.001) from pre-dose concentrations in response to SMB and AMB. There was no difference in lutein T max between the two test articles. However, by 14 h post-dose, total plasma lutein increased by 7 % with AMB and by 126 % with SMB. Total lutein AUC (0–72h) and AUC (0–672h) were 1.8-fold and 1.3-fold higher, respectively, for SMB compared to AMB. Both formulations were well tolerated by subjects in this study. Conclusion These findings confirm that the bioavailability of lutein and zeaxanthin critically depends on the formulation used and document a superiority of the starch-based over the alginate-based product in this study.

Purpose: To assess the effects of nilvadipine on the progression of central visual field defect in retinitis pigmentosa (RP). Design: Prospective, randomized, nonmasked, single-center trial. Methods: Patients with RP were randomly divided into a treated group receiving oral nilvadipine at 4 mg/day for ≧30 months and a control group receiving tocopherol nicotinate at 300 mg/day, helenien at 15 mg/day or no medication for the same periods. Progression of RP was evaluated using the 10-2 SITA Fast Program of the Humphrey Visual Field Analyzer, and regression coefficients calculated from the time courses of mean deviation (MD slope) were compared between groups. Results: Nineteen patients in the treated group and 14 patients in the control group completed the follow-up for ≧30 months. The mean (±standard deviation) duration of observation was 48.8 ± 11.8 months (median 48 months, range 30–66 months) for the treated group and 49.2 ± 18.1 months (median 48 months, range 30–90 months) for the control group (p = 0.94). Mean (±standard error of the mean, SEM) regression coefficients of the averaged MD values for the initial 30 months were –0.35 ± 0.17 dB/year in the treated group and –0.75 ± 0.06 dB/year in the control group (p < 0.01). Mean (±SEM) MD slopes for total observational periods were –0.49 ± 0.17 dB/year in the treated group and –0.89 ± 0.16 dB/year in the control group (mean ± SEM, p = 0.042). Conclusion: Nilvadipine at 4 mg/day significantly retarded progression of central visual field defects in RP in this small patient series.

The photoprotective role of the universal violaxanthin cycle that interconverts violaxanthin (V), antheraxanthin (A), and zeaxanthin (Z) is well established, but functions of the analogous conversions of lutein-5,6-epoxide (Lx) and lutein (L) in the selectively occurring Lx cycle are still unclear. We investigated carotenoid pools in Lx-rich leaves of avocado (Persea americana) during sun or shade acclimation at different developmental stages. During sun exposure of mature shade leaves, an unusual decrease in L preceded the deepoxidation of Lx to L and of V to A+ Z. In addition to deepoxidation, de novo synthesis increased the L and A+ Z pools. Epoxidation of L was exceptionally slow, requiring about 40 d in the shade to restore the Lx pool, and residual A+ Z usually persisted overnight. In young shade leaves, the Lx cycle was reversed initially, with Lx accumulating in the sun and declining in the shade. De novo synthesis of xanthophylls did not affect a-and -carotene pools on the first day, but during long-term acclimation a-carotene pools changed noticeably. Nonetheless, the total change in a-and β-branch carotenoid pools was equal. We discuss the implications for regulation of metabolic flux through the a-and β-branches of carotenoid biosynthesis and potential roles for L in photoprotection and Lx in energy transfer to photosystem II and explore physiological roles of both xanthophyll cycles as determinants of photosystem II efficiency.

The lutein-5,6-epoxide (Lx) cycle operates in some plants between lutein (L) and its monoepoxide, Lx. Whereas recent studies have established the photoprotective roles of the analogous violaxanthin cycle, physiological functions of the Lx cycle are still unknown. In this article, we investigated the operation of the Lx cycle in light-harvesting antenna complexes (Lhcs) of Inga sapindoides Willd, a tropical tree legume accumulating substantial Lx in shade leaves, to identify the xanthophyll-binding sites involved in short- and long-term responses of the Lx cycle and to analyze the effects on light-harvesting efficiency. In shade leaves, Lx was converted into L upon light exposure, which then replaced Lx in the peripheral V1 site in trimeric Lhcs and the internal L2 site in both monomeric and trimeric Lhcs, leading to xanthophyll composition resembling sun-type Lhcs. Similar to the violaxanthin cycle, the Lx cycle was operating in both photosystems, yet the light-induced Lx [rightward arrow] L conversion was not reversible overnight. Interestingly, the experiments using recombinant Lhcb5 reconstituted with different Lx and/or L levels showed that reconstitution with Lx results in a significantly higher fluorescence yield due to higher energy transfer efficiencies among chlorophyll (Chl) a molecules, as well as from xanthophylls to Chl a. Furthermore, the spectroscopic analyses of photosystem I-LHCI from I. sapindoides revealed prominent red-most Chl forms, having the lowest energy level thus far reported for higher plants, along with reduced energy transfer efficiency from antenna pigments to Chl a. These results are discussed in the context of photoacclimation and shade adaptation.

The kinetics of response to strong light have been examined in deeply shaded leaves of the tropical tree legume (Inga sp.) which have extraordinarily high levels of the [alpha]-xanthophyll lutein-epoxide that are co-located in pigment-protein complexes of the photosynthetic apparatus with the {szligbeta}-xanthophyll violaxanthin. As in other species, rapidly reversible photoprotection (measured as non-photochemical chlorophyll fluorescence quenching) is initiated within the time frame of sun-flecks (minutes), before detectable conversion of violaxanthin to antheraxanthin or zeaxanthin. Photoprotection is stabilized within hours of exposure to strong light by simultaneously engaging the reversible violaxanthin cycle and a slowly reversible conversion of lutein-epoxide to lutein. It is proposed that this lutein 'locks in' a primary mechanism of photoprotection during photoacclimation in this species, converting efficient light-harvesting antennae of the shade plant into potential excitation dissipating centres. It is hypothesized that lutein occupies sites L2 and V1 in light-harvesting chlorophyll protein complexes of photosystem II, facilitating enhanced photoprotection through the superior singlet and/or triplet chlorophyll quenching capacity of lutein.

Breastfed infants require an adequate supply of critical nutrients for growth, tissue functions, and health. Recommended intakes for several nutrients are considerably higher in lactating than non-lactating women but are not always met with habitual diets. We report a randomized, double-blind clinical trial in 70 healthy lactating women in Germany evaluating the effects of supplementation with multiple micronutrients, lutein, and docosahexaenoic acid (DHA) compared to placebo on maternal nutrient status and milk composition. The primary endpoint was the effect on the change of human milk DHA content (as a proportion of total milk fatty acids) during 12 weeks of supplementation. Maternal blood and milk biomarkers were measured as secondary endpoints. Supplementation increased maternal milk DHA by 30% compared to a decline in the placebo group. Supplementation also increased maternal blood DHA (17%), eicosapentaenoic acid (4%), 25-OH-vitamin D (24%), vitamin B12 (12%), lutein (4%), and beta carotene (49%), while homocysteine decreased. No significant difference in the number of adverse events was observed between supplementation and placebo groups. In conclusion, multi-micronutrient supplementation was safe and increased maternal blood and milk concentrations of selected nutrients in healthy women.

Glycation is known as an important factor inducing human diseases, including diabetic complications. As oxidative stress contributes to procedures of glycation, antioxidants may inhibit glycation and delay the progression of diabetic complications. Our previous investigation of human aqueous humor after the intake of a lutein-containing supplement demonstrated increases in antioxidative activities and decreases in peroxidative products. This study enrolled 25 patients with diabetes (DM group) and 100 age-matched controls. Aqueous humor samples were collected during cataract surgery before and after 6 weeks of oral intake of the lutein-containing antioxidant supplement, Ocuvite + Lutein®. The carboxymethyl-lysine level (CML) was measured as an indicator of glycation. Levels of superoxide dismutase activities (SOD) and total hydroperoxide (TH) were measured as indicators of oxidation. Changes after intake and the differences between age-matched controls and the DM group were evaluated. CML decreased after intake among the DM group, while there were no changes among the age-matched controls. SOD was significantly lower and TH was significantly higher in the DM group as compared to the age-matched controls, both before and after intake. In line with the decreases in glycation, the intake of lutein-containing antioxidant supplements may inhibit diabetic complications in diabetic patients.

The purpose of this study is evaluate the efficacy and safety of medicinal products containing the original Age-Related Eye Disease group (AREDS) formulation at doses approved in Europe (EU, control group; n = 59) with a product that adds DHA, lutein, zeaxanthin, resveratrol and hydroxytyrosol to the formula (intervention group; n = 50). This was a multicenter, randomized, observer-blinded trial conducted in patients aged 50 years or older diagnosed with unilateral exudative Age related Macular Degeneration AMD. At month 12, the intervention did not have a significant differential effect on visual acuity compared with the control group, with an estimated treatment difference in Early Treatment Diabetic Retinopathy Study (ETDRS) of −1.63 (95% CI −0.83 to 4.09; p = 0.192). The intervention exhibited a significant and, in most cases, relevant effect in terms of a reduction in some inflammatory cytokines and a greater improvement in the fatty acid profile and serum lutein and zeaxantin concentration. In patients with unilateral wet AMD, the addition of lutein, zeaxanthin, resveratrol, hydroxytyrosol and DHA to the AREDS EU recommended doses in the short-term did not have a differential effect on visual acuity compared to a standard AREDS EU formula but, in addition to improving the fatty acid profile and increasing carotenoid serum levels, may provide a beneficial effect in improving the proinflammatory and proangiogenic profile of patients with AMD.

The macular region of the primate retina is yellow in color due to the presence of the macular pigment, composed of two dietary xanthophylls, lutein and zeaxanthin, and another xanthophyll, meso-zeaxanthin. The latter is presumably formed from either lutein or zeaxanthin in the retina. By absorbing blue-light, the macular pigment protects the underlying photoreceptor cell layer from light damage, possibly initiated by the formation of reactive oxygen species during a photosensitized reaction. There is ample epidemiological evidence that the amount of macular pigment is inversely associated with the incidence of age-related macular degeneration, an irreversible process that is the major cause of blindness in the elderly. The macular pigment can be increased in primates by either increasing the intake of foods that are rich in lutein and zeaxanthin, such as dark-green leafy vegetables, or by supplementation with lutein or zeaxanthin. Although increasing the intake of lutein or zeaxanthin might prove to be protective against the development of age-related macular degeneration, a causative relationship has yet to be experimentally demonstrated.

The present cross-sectional study assessed the potential relationships of carotenoid intake with lipid and oxidative stress markers in middle-aged men. A total of 296 apparently healthy middle-aged men (mean age 50·5 (sd 5·0) years, BMI 25·8 (sd 3·5) kg/m2) were recruited to participate in the study. Dietary intake, anthropometry, blood pressure, lifestyle features, blood and urine biomarkers were assessed using validated procedures. The lipid markers included NEFA, Castelli index, and TAG:HDL ratio; oxidative stress markers included urinary 8-hydroxy-2′-deoxyguanosine (8-OHdG), 8-iso-PGF2α and plasma oxidised-LDL (ox-LDL). We observed a significant inverse association (P< 0·05) between NEFA concentrations and consumption of lutein plus zeaxanthin, β-carotene, α-carotene and total carotenoid, while Castelli index was negatively associated with daily intake of lycopene, β-carotene and total carotenoids. Regarding oxidative stress biomarkers, urinary 8-OHdG and ox-LDL concentrations were also inversely associated (P< 0·05) with consumption of lycopene, lutein plus zeaxanthin, β-carotene, α-carotene and total carotenoids, regardless of confounding variables. Moreover, there was a negative association of urinary 8-iso-PGF2α concentration with dietary lutein plus zeaxanthin (β − 0·135, 95 % CI − 0·268, − 0·001), β-carotene (β − 0·156, 95 % CI − 0·277, − 0·034) and with the sum of all carotenoids (β − 0·189, 95 % CI − 0·333, − 0·046). In conclusion, total daily carotenoid intake based on five investigated carotenoid types (β-cryptoxanthin, lycopene, lutein plus zeaxanthin, β-carotene and α-carotene) was inversely associated with relevant lipid and oxidative stress markers in middle-aged men, with emphasis on β-carotene that was negatively associated with five of the six lipid and oxidative stress markers evaluated in the present study.