Serum Zeaxanthin Concentrations Research Articles

Association between Advanced Glycation End-Products, Carotenoids, and Severe Erectile Dysfunction.

To investigate the association between skin advanced glycation end-products (AGEs) levels, blood antioxidative vitamin and carotenoid concentrations, and severe erectile dysfunction (ED) in community-dwelling men. This cross-sectional study used the 5-Item International Index of Erectile Function to identify 335 community-dwelling men with ED. The accumulation of skin AGEs was assessed noninvasively by measuring skin autofluorescence. Background-adjusted multivariable logistic regression analyses using the inverse probability of treatment weighting method were performed to evaluate the effects of AGEs, vitamins, and carotenoids on severe ED. Moreover, multiple linear regression analyses were performed to assess the association between skin AGEs levels and serum carotenoid concentrations. The median age of study participants was 57 years. Of the 335 men, 289 (86.3%) and 46 (13.7%) were classified into the mild/moderate and severe ED groups, respectively. Multivariable analyses revealed that skin AGEs levels, blood vitamins C and E, lutein, zeaxanthin, β-cryptoxanthin, α-carotene, β-carotene, total lycopene, and cis-lycopenes concentrations were significantly associated with severe ED, whereas all-trans lycopene concentrations were not. In the multiple linear regression analyses, serum zeaxanthin concentrations were negatively and significantly correlated with skin AGEs levels. Higher skin AGEs levels and lower blood antioxidative vitamin and carotenoid concentrations were significantly associated with severe ED. Serum zeaxanthin levels were negatively and significantly correlated with skin AGEs levels, suggesting the possible effects of zeaxanthin on ED by decreasing tissue AGEs levels.

(3R, 3’R)-zeaxanthin protects the retina from photo-oxidative damage via modulating the inflammation and visual health molecular markers

Purpose: Zeaxanthin protects the macula from ocular damage due to light or radiation by scavenging harmful reactive oxygen species. In the present study, zeaxanthin product (OmniXan®; OMX), derived from paprika pods (Capsicum annum; Family-Solanaceae), was tested for its efficacy in the rat retina against photooxidation.Methods: Forty-two male 8-week-old Wistar rats exposed to 12L/12D, 16L/8D and 24L/0D hours of intense light conditions were orally administrated either 0 or 100 mg/kg BW of zeaxanthin concentration. Retinal morphology was analyzed by histopathology, and target gene expressions were detected with real-time polymerase chain reaction methods.Results: OMX treatment significantly increased the serum zeaxanthin concentration (p < 0.001) and ameliorated oxidative damage by increasing the antioxidant enzyme activities in the retina induced by light (p < 0.001). OMX administration significantly upregulated the expression of genes, including Rhodopsin (Rho), Rod arrestin (SAG), Gα Transducin 1 (GNAT-1), neural cell adhesion molecule (NCAM), growth-associated protein 43 (GAP43), nuclear factor-(erythroid-derived 2)-like 2 (Nrf2) and heme oxygenase (HO-1) and decreased the expression of nuclear factor-κB (NF- κB) and GFAP by OMX treatment rats. The histologic findings confirmed the antioxidant and gene expression data.Conclusions: This study suggests that OMX is a potent substance that can be used to protect photoreceptor cell degeneration in the retina exposed to intense light.

Correlations Between Macular, Skin, and Serum Carotenoids.

PurposeOcular and systemic measurement and imaging of the macular carotenoids lutein and zeaxanthin have been employed extensively as potential biomarkers of AMD risk. In this study, we systematically compare dual wavelength retinal autofluorescence imaging (AFI) of macular pigment with skin resonance Raman spectroscopy (RRS) and serum carotenoid levels in a clinic-based population.MethodsEighty-eight patients were recruited from retina and general ophthalmology practices from a tertiary referral center and excluded only if they did not have all three modalities tested, had a diagnosis of macular telangiectasia (MacTel) or Stargardt disease, or had poor AFI image quality. Skin, macular, and serum carotenoid levels were measured by RRS, AFI, and HPLC, respectively.ResultsSkin RRS measurements and serum zeaxanthin concentrations correlated most strongly with AFI macular pigment volume under the curve (MPVUC) measurements up to 9° eccentricity relative to MPVUC or rotationally averaged macular pigment optical density (MPOD) measurements at smaller eccentricities. These measurements were reproducible and not significantly affected by cataracts. We also found that these techniques could readily identify subjects taking oral carotenoid-containing supplements.ConclusionsLarger macular pigment volume AFI and skin RRS measurements are noninvasive, objective, and reliable methods to assess ocular and systemic carotenoid levels. They are an attractive alternative to psychophysical and optical methods that measure MPOD at a limited number of eccentricities. Consequently, skin RRS and MPVUC at 9° are both reasonable biomarkers of macular carotenoid status that could be readily adapted to research and clinical settings.

Comparison of macular pigment optical density in patients with dry and wet age-related macular degeneration

Aim:The aim of the study was to evaluate the macular pigment optical density (MPOD) levels in patients with wet age-related macular degeneration (AMD), dry AMD, and also in healthy controls.Settings and Design:This study was conducted at Department of Ophthalmology, and the study design was a prospective study.Patients and Methods:Forty-eight patients with wet AMD, 51 patients with dry AMD, and 50 controls were included in the study. All patients were naive to both previous lutein or zeaxanthin administration and any previous intravitreal injections. Fundus reflectance (VISUCAM 500, reflectance of a single 460 nm wavelength) was used to measure the MPOD levels. Three groups were compared regarding age, gender, serum lutein, and zeaxanthin concentrations as well as MPOD levels.Results:Serum lutein and zeaxanthin levels were significantly higher in control group when compared with wet AMD (Group 1) and dry AMD (Group 2) (P = 0.001 and P < 0.001, respectively). Mean MPOD was found to be similar in all of the three study subgroups (P = 0.630). However, maximum MPOD was significantly higher in control group when compared with Group 1 and 2 (P = 0.003). There was no correlation between serum lutein or zeaxanthin concentrations and mean MPOD levels (P = 0.815, r = 0.014 and P = 0.461, r = 0.043, respectively), but there was a weak correlation between serum zeaxanthin concentration and maximum MPOD level (P = 0.042, r = 0.124). Maximum MPOD level was found to be correlated with the level of AMD (Group 1, 2, and 3; r = 0.184, P = 0.041).Conclusion:Maximum MPOD level was found to be lower in patients with AMD when compared with control cases. Mean MPOD and maximum MPOD levels were similar in wet and dry AMD Groups. These results can be applied clinically keeping in mind that MPOD measurements with one wavelength reflectometry may not be completely reliable.

Consumption of 12 eggs per week for 1 year increases serum zeaxanthin concentrations but not other major carotenoids, tocopherols, and retinol in humans (645.25)

Previous work has shown that egg yolk consumption yields increase bioavailability of lutein and zeaxanthin compared to dietary supplements. However, little is known of the effects of an egg‐rich diet on serum levels of the other carotenoids, vitamin A and vitamin E. This study investigated how a diet of 12 eggs per week for 1 year influenced serum carotenoid, tocopherol, and retinol concentrations in adults. A group of 45 adults were placed into either the intervention group (n=27; consumed 12 eggs per week for 12 months) or control group (n=18; consumed no eggs or high egg products for 12 months) after 6 weeks of an egg‐free diet. Serum carotenoid and vitamin concentrations were measured by high performance liquid chromatography (HPLC) at baseline and 12 months. Seven day diet records were collected and analyzed on a monthly basis to help ensure the egg consumption protocol. Results showed that the intervention group demonstrated a statistically significant increase (83%) in serum zeaxanthin concentrations after 12 months. A notable, but not statistically significant, increase in serum lutein concentration was also observed in the intervention group (52%) after 12 months. Although serum alpha‐carotene concentration did not change in the intervention group, it significantly increased in the control group (18%) after 12 months. No other serum carotenoid, retinol, or alpha‐ or gamma‐tocopherol concentrations changed significantly during the 12 months. The findings of this study suggest that egg yolk consumption does not significantly alter the serum concentrations of tocopherols, retinol, and carotenoids other than alpha‐carotene and zeaxanthin.Grant Funding Source: Supported by the Egg Nutrition Center

The Effect of Modified Eggs and an Egg-Yolk Based Beverage on Serum Lutein and Zeaxanthin Concentrations and Macular Pigment Optical Density: Results from a Randomized Trial

Increasing evidence suggests a beneficial effect of lutein and zeaxanthin on the progression of age-related macular degeneration. The aim of this study was to investigate the effect of lutein or zeaxanthin enriched eggs or a lutein enriched egg-yolk based buttermilk beverage on serum lutein and zeaxanthin concentrations and macular pigment levels. Naturally enriched eggs were made by increasing the levels of the xanthophylls lutein and zeaxanthin in the feed given to laying hens. One hundred healthy volunteers were recruited and randomized into 5 groups for 90 days. Group one added one normal egg to their daily diet and group two received a lutein enriched egg-yolk based beverage. Group three added one lutein enriched egg and group four one zeaxanthin enriched egg to their diet. Group five was the control group and individuals in this group did not modify their daily diet. Serum lutein and zeaxanthin concentrations and macular pigment densities were obtained at baseline, day 45 and day 90. Macular pigment density was measured by heterochromatic flicker photometry. Serum lutein concentration in the lutein enriched egg and egg yolk-based beverage groups increased significantly (p<0.001, 76% and 77%). A strong increase in the serum zeaxanthin concentration was observed in individuals receiving zeaxanthin enriched eggs (P< 0.001, 430%). No changes were observed in macular pigment density in the various groups tested. The results indicate that daily consumption of lutein or zeaxanthin enriched egg yolks as well as an egg yolk-based beverage show increases in serum lutein and zeaxanthin levels that are comparable with a daily use of 5 mg supplements.Trial RegistrationClinicalTrials.gov NCT00527553

Serum and macular responses to multiple xanthophyll supplements in patients with early age-related macular degeneration

ObjectiveThis randomized controlled trial examined serum and macular (in vivo measured macular pigment optical density [MPOD]) responses to supplemental lutein and zeaxanthin in Chinese subjects with early age-related macular degeneration. MethodsOne hundred and eight patients with early age-related macular degeneration older than 50 y were randomized to low lutein (LL; 10 mg/d), high lutein (HL; 20 mg/d), lutein plus zeaxanthin (LZ; each 10 mg/d), or placebo during a 48-wk intervention. Serum concentrations were quantified by C30 high-performance liquid chromatography (at baseline and 4, 12, 24, and 48 wk), and MPOD was measured by analysis of autofluorescence images (at baseline and 24 and 48 wk). ResultsSerum lutein levels in the LL, LZ, and HL groups increased significantly in the first 4 wk and then increased 4.24-, 4.66-, and 6.23-fold during the trial, respectively (all P < 0.001). The serum lutein level in the HL group was significantly higher than that in the LL or LZ group at 48 wk (P < 0.05). Similarly, the serum zeaxanthin concentration in the LZ group increased 3.11-fold at 48 wk. MPOD increased smoothly in all treated groups, and the increase from baseline was greatest in the HL group at 24 and 48 wk (both P < 0.05). MPOD and serum lutein levels increased linearly with the dosage and their increasing rates were statistically correlated (all P < 0.05). No notable changes were detected in the placebo group for MPOD and serum concentrations. ConclusionXanthophyll supplementation significantly increased serum concentrations and MPOD in patients with early age-related macular degeneration, and a higher lutein supplementation (20 mg/d) might be more effective in increasing these two biochemical markers in Chinese patients without significant side effects.

Spirulina is an effective dietary source of zeaxanthin to humans

Zeaxanthin is a predominant xanthophyll in human eyes and may reduce the risk of cataracts and age-related macular degeneration. Spirulina is an algal food that contains a high concentration of zeaxanthin. In order to determine the zeaxanthin bioavailability of spirulina for dietary supplementation in humans, spirulina was grown in nutrient solution with ²H₂O for carotenoid labelling. Single servings of ²H-labelled spirulina (4.0-5.0 g) containing 2.6-3.7 mg zeaxanthin were consumed by fourteen healthy male volunteers (four Americans and ten Chinese) with 12 g dietary fat. Blood samples were collected over a 45 d period. The serum concentrations of total zeaxanthin were measured using HPLC, and the enrichment of labelled zeaxanthin was determined using LC-atmospheric pressure chemical ionisation-MS (LC-APCI-MS). The results showed that intrinsically labelled spirulina zeaxanthin in the circulation was detected at levels as low as 10 % of the total zeaxanthin for up to 45 d after intake of the algae. A single dose of spirulina can increase mean serum zeaxanthin concentration in humans from 0.06 to 0.15 μmol/l, as shown in our study involving American and Chinese volunteers. The average 15 d area under the serum zeaxanthin response curve to the single dose of spirulina was 293 nmol × d/μmol (range 254-335) in American subjects, and 197 nmol × d/μmol (range 154-285) in Chinese subjects. It is concluded that the relative bioavailability of spirulina zeaxanthin can be studied with high sensitivity and specificity using ²H labelling and LC-APCI-MS methodology. Spirulina can serve as a rich source of dietary zeaxanthin in humans.

Relation among serum and tissue concentrations of lutein and zeaxanthin and macular pigment density

Lutein and zeaxanthin are the only carotenoids in the macular region of the retina (referred to as macular pigment [MP]). Foods that are rich in lutein and zeaxanthin can increase MP density. Response to dietary lutein and zeaxanthin in other tissues has not been studied. The objective of this study was to examine tissue responses to dietary lutein and zeaxanthin and relations among tissues in lutein and zeaxanthin concentrations. Seven subjects consumed spinach and corn, which contain lutein and zeaxanthin, with their daily diets for 15 wk. At 0, 4, 8, and 15 wk and 2 mo after the study, serum, buccal mucosa cells, and adipose tissue were analyzed for carotenoids, and MP density was measured. Serum and buccal cell concentrations of lutein increased significantly from baseline during dietary modification. Serum zeaxanthin concentrations were greater than at baseline only at 4 wk, whereas buccal cell and adipose tissue concentrations of zeaxanthin did not change. Adipose tissue lutein concentrations peaked at 8 wk. Changes in adipose tissue lutein concentration were inversely related to the changes in MP density, suggesting an interaction between adipose tissue and retina in lutein metabolism. To investigate the possibility of tissue interactions, we examined cross-sectional relations among serum, tissue, and dietary lutein concentrations, anthropometric measures, and MP density in healthy adults. Significant negative correlations were found between adipose tissue lutein concentrations and MP for women, but a significant positive relation was found for men. Sex differences in lutein metabolism may be an important factor in tissue interactions and in determining MP density.