zeaxanthin and Cognition-Disorders

Lutein (L) and zeaxanthin (Z) are dietary carotenoids derived from dark green leafy vegetables, orange and yellow fruits that form the macular pigment of the human eyes. It was hypothesized that they protect against visual disorders and cognition diseases, such as age-related macular degeneration (AMD), age-related cataract (ARC), cognition diseases, ischemic/hypoxia induced retinopathy, light damage of the retina, retinitis pigmentosa, retinal detachment, uveitis and diabetic retinopathy. The mechanism by which they are involved in the prevention of eye diseases may be due their physical blue light filtration properties and local antioxidant activity. In addition to their protective roles against light-induced oxidative damage, there are increasing evidences that L and Z may also improve normal ocular function by enhancing contrast sensitivity and by reducing glare disability. Surveys about L and Z supplementation have indicated that moderate intakes of L and Z are associated with decreased AMD risk and less visual impairment. Furthermore, this review discusses the appropriate consumption quantities, the consumption safety of L, side effects and future research directions.

Topics: Age Factors; Animals; Cognition; Cognition Disorders; Dietary Supplements; Humans; Lutein; Macular Degeneration; Molecular Structure; Vision Disorders; Zeaxanthins

Patients with Alzheimer's disease (AD) exhibit significantly less macular pigment (MP) and poorer vision when compared to control subjects.. To investigate supplementation with the macular carotenoids on MP, vision, and cognitive function in patients with AD versus controls.. 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)).. 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).. 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.

Topics: Aged; Aged, 80 and over; Alzheimer Disease; Antioxidants; Carotenoids; Chromatography, High Pressure Liquid; Cognition Disorders; Contrast Sensitivity; Dietary Supplements; Double-Blind Method; Female; Humans; Longitudinal Studies; Lutein; Macular Pigment; Male; Mental Status Schedule; Neuropsychological Tests; Visual Acuity; Zeaxanthins

Macular pigment (MP) levels correlate with brain concentrations of lutein (L) and zeaxanthin (Z), and have also been shown to correlate with cognitive performance in the young and elderly.. To investigate the relationship between MP, serum concentrations of L and Z, and cognitive function in subjects free of retinal disease with low MP (Group 1, n = 105) and in subjects with AMD (Group 2, n = 121).. MP was measured using customized heterochromatic flicker photometry and dual-wavelength autofluorescence; cognitive function was assessed using a battery of validated cognition tests; serum L and Z concentrations were determined by HPLC.. Significant correlations were evident between MP and various measures of cognitive function in both groups (r = -0.273 to 0.261, p≤0.05, for all). Both serum L and Z concentrations correlated significantly (r = 0.187, p≤0.05 and r = 0.197, p≤0.05, respectively) with semantic (animal) fluency cognitive scores in Group 2 (the AMD study group), while serum L concentrations also correlated significantly with Verbal Recognition Memory learning slope scores in the AMD study group (r = 0.200, p = 0.031). Most of the correlations with MP, but not serum L or Z, remained significant after controlling for age, gender, diet, and education level.. MP offers potential as a non-invasive clinical biomarker of cognitive health, and appears more successful in this role than serum concentrations of L or Z.

Topics: Adult; Aged; Carotenoids; Chromatography, High Pressure Liquid; Cognition Disorders; Double-Blind Method; Female; Humans; Lutein; Macular Degeneration; Macular Pigment; Male; Middle Aged; Neuropsychological Tests; Photometry; Tomography, Optical Coherence; Zeaxanthins

Alzheimer's disease (AD) is a progressive, neurodegenerative disease, characterised by decline of memory, cognitive function and changes in behaviour. Generic markers of lipid peroxidation are increased in AD and reactive oxygen species have been suggested to be involved in the aetiology of cognitive decline. Carotenoids are depleted in AD serum, therefore we have compared serum lipid oxidation between AD and age-matched control subjects before and after carotenoid supplementation. The novel oxidised phospholipid biomarker 1-palmitoyl-2-(5'-oxo-valeroyl)-sn-glycero-3-phosphocholine (POVPC) was analysed using electrospray ionisation tandem mass spectrometry (MS) with multiple reaction monitoring (MRM), 8-isoprostane (IsoP) was measured by ELISA and ferric reducing antioxidant potential (FRAP) was measured by a colorimetric assay. AD patients (n=21) and healthy age-matched control subjects (n=16) were supplemented with either Macushield™ (10mg meso-zeaxanthin, 10mg lutein, 2mg zeaxanthin) or placebo (sunflower oil) for six months. The MRM-MS method determined serum POVPC sensitively (from 10µl serum) and reproducibly (CV=7.9%). At baseline, AD subjects had higher serum POVPC compared to age-matched controls, (p=0.017) and cognitive function was correlated inversely with POVPC (r=-0.37; p=0.04). After six months of carotenoid intervention, serum POVPC was not different in AD patients compared to healthy controls. However, POVPC was significantly higher in control subjects after six months of carotenoid intervention compared to their baseline (p=0.03). Serum IsoP concentration was unrelated to disease or supplementation. Serum FRAP was significantly lower in AD than healthy controls but was unchanged by carotenoid intervention (p=0.003). In conclusion, serum POVPC is higher in AD patients compared to control subjects, is not reduced by carotenoid supplementation and correlates with cognitive function.

Topics: Aged; Aged, 80 and over; Alzheimer Disease; Antioxidants; Biomarkers; Carotenoids; Cognition Disorders; Combined Modality Therapy; Dietary Supplements; Female; Humans; Lipid Peroxidation; Lutein; Male; Oxidation-Reduction; Phospholipid Ethers; Phospholipids; Reactive Oxygen Species; Zeaxanthins

Published studies have shown that cognitive deficit is a characteristic manifestation of neurodegenerative disease in diabetes. However, there is no effective prevention and treatment for this diabetes-associated behavior disorder. In the present study, we attempted to elucidate the effect of zeaxanthin on cognitive deficit and the change in the hippocampus correlated with cognitive decline in diabetic rats. Diabetic rats in this study were induced by high-fat diet and low-dose streptozocin (STZ), cognitive ability of rats were evaluated use morris water maze (MWM) and morphology change in hippocampus was assessed by cresyl violet stain. Moreover, we detected the expression of phosphorylated serine/threonine kinase (p-AKT) and Cleaved caspase-3, and the activity of nuclear factor-κB (NF-κB) use western-blot (WB). Results displayed that supplementation with zeaxanthin reduce blood glucose, improve cognitive deficit, survive neural cell, increase p-AKT level, inhibit Cleaved caspase-3 level and NF-κB nuclear transcription in hippocampus. This study demonstrated that zeaxanthin ameliorate diabetes-related cognitive deficit may by means of protecting neural cell from hyperglycemia involved in AKT/NF-κB signaling pathway. This study may provide a potential therapeutic approach for the prevention of diabetes- associated cognitive deficit.

Topics: Active Transport, Cell Nucleus; Animals; Caspase 3; Cell Survival; Cognition Disorders; Diabetes Mellitus, Experimental; Hippocampus; Hypoglycemic Agents; Male; Maze Learning; Neurons; Neuroprotective Agents; NF-kappa B; Nootropic Agents; Phosphatidylinositol 3-Kinases; Proto-Oncogene Proteins c-akt; Rats, Sprague-Dawley; Signal Transduction; Zeaxanthins

A large body of literature suggests that the dietary carotenoids lutein and zeaxanthin and long-chain polyunsaturated fatty acids such as docosahexaenoic acid are related to improved cognitive function across the life span. A recent report by the Age-Related Eye Disease Study (AREDS) group appears to contradict the general findings of others in the field. In this review, we look critically at the methods, study designs, and analysis techniques used in the larger body of literature and compare them with the recent AREDS reports.

Topics: Aged; Aging; Clinical Trials as Topic; Cognition Disorders; Fatty Acids; Female; Humans; Lutein; Macular Degeneration; Male; Research Design; Zeaxanthins

The hypothesis of carotenoids having a preventive role in cognitive impairment is suggested by their antioxidant properties.. We examined, in a cross-sectional analysis, the relationship between cognitive performance (assessed by the Mini-Mental State Examination, Trail Making Test Part B, Digit Symbol Substitution, Finger Tapping Test, and Word Fluency Test) and different plasma carotenoids (lutein, zeaxanthin, beta-cryptoxanthin, lycopene, alpha-carotene, and trans-beta-carotene and cis-beta-carotene) in a healthy elderly population (the EVA,"Etude du Vieillissement Artériel," study; n = 589, age = 73.5 +/- 3 years).. Logistic regression showed that participants with the lowest cognitive functioning (<25th percentile) had a higher probability of having low levels of specific plasma carotenoids (<1st quartile): lycopene and zeaxanthin. For zeaxanthin, odds ratios (ORs) were as follows: OR(DSS) = 1.97 (95% confidence interval [CI] = 1.21-3.20), OR(FTT) = 1.70 (CI = 1.05-2.74), and OR(WFT) = 1.82 (CI = 1.08-3.07); for lycopene, OR(DSS) = 1.93 (CI = 1.20-3.12) and OR(TMTB) = 1.64 (CI = 1.04-2.59).. Even if it is not possible to affirm if these low levels of carotenoids precede or are the consequence of cognitive impairment, our results suggest that low carotenoid levels could play a role in cognitive impairment. The biological significance of our findings needs further research.

Topics: Aged; Antioxidants; beta Carotene; Carotenoids; Cognition; Cognition Disorders; Cross-Sectional Studies; Cryptoxanthins; Female; Follow-Up Studies; Humans; Longitudinal Studies; Lutein; Lycopene; Male; Mental Status Schedule; Motor Skills; Sensitivity and Specificity; Stereoisomerism; Trail Making Test; Verbal Behavior; Xanthophylls; Zeaxanthins