Arterial cord blood lutein levels in preterm and term healthy newborns are sex and gestational age dependent

Objective

Lutein is an antioxidant carotenoid exerting a key role in eye health, but no reference curve in the perinatal period is available.

Design and methods

We conducted a prospective study on the distribution of lutein and its metabolite 3′-oxolutein in arterial cord blood of preterm (n = 40) and term (n = 76) newborns according to gestational age, sex and delivery modalities.

Results

Lutein and 3′-oxolutein concentrations peaked at the beginning of third trimester (P < 0.01, for both) being higher in the preterm than in term group. From 36 weeks onwards, lutein and 3′-oxolutein levels progressively decreased reaching the lowest levels at term between 41 and 42 weeks (P < 0.01, for both). Lutein and 3′-oxolutein significantly (P < 0.01, for all) correlated with each other (R = 0.33) and with gestational age at sampling (R = 0.31 and R = 0.38 for lutein and 3-oxolutein, respectively) (P < 0.001, for all). Indeed, lutein and 3′-oxolutein concentrations were significantly higher (P < 0.05, for all) in female than in male and significantly lower (P < 0.01, for both) in newborns delivered by caesarean section when compared to vaginal delivery.

Conclusions

Since macula densa and retina are sites of lutein accumulation, the present findings open-up a new cue on the potential role of lutein in the prevention of the retinopathy of prematurity.     

叶黄素对小鼠葡萄膜炎氧化应激状态的改善作用

<正>葡萄膜炎发病机制尚未完全解明,因此人们十分关注对其预防和治疗的研究[1]。Bosch-Morell等[2]认为自由基清除剂和抗氧化剂可以缓解炎症反应,以及减轻炎症对眼组织的损伤。     

Preparation optimisation and storage stability of nanoemulsion-based lutein delivery systems

Abstract

The present work formed lutein-enriched nanoemulsions stabilised by sodium caseinate (SC) using a high-pressure homogenisation process, and the influence of environmental conditions on the physicochemical stability of the nanoemulsion was investigated. The results showed that the droplet diameter of the nanoemulsion was largely dependent on homogenisation conditions. Optimum results were obtained for 1.0% (w/w) SC, 100?MPa pressure, and 7 homogenisation cycles, which produced a nanoemulsion with a mean droplet diameter of 234.01?±?3.40?nm, polydispersity index of 0.123?±?0.028, and zeta potential of ?36.56?±?1.51?mV. The nanoemulsion remained physically stable after a 30 d storage at 4?°C, and the chemical degradation rate of lutein was considerably decreased. Thermal treatment at 60–100?°C had little effect on its physicochemical stability; conversely, pH, ionic strength (NaCl or CaCl₂), concentration treatment, and freeze–thaw cycling had major impacts on the physicochemical stability of nanoemulsion.     

叶黄素和玉米黄质治疗年龄相关性黄斑变性的多焦视网膜电图变化观察

目的 应用多焦视网膜电图(multifocal electroretinography,mfERC)评价叶黄素(lutein)和玉米黄质(zeaxanthin)治疗年龄相关性黄斑变性(age-related macular degeneration,ARMD)的视网膜功能变化情况.方法 ARMD患者6例9只眼在接受叶黄素和玉米黄质治疗前及治疗后100d分别对各患眼5个环状视网膜区域进行b波反应密度的测量比较.记录以黄斑中心凹为中心呈同心圆排列的5个环区,自内至外分别是1环(2.18度),2环(7.46度),3环(12.36度),4环(19.66度)和5环(29.75度)的b波反应振幅密度,应用EPi Info统计软件中两个独立样本的t检验进行统计学分析.结果 9只眼ARMD患者治疗前后mf-ERG b波反应振幅密度比较,1,2,3,4,5环各环的振幅密度均明显提高,与治疗前相比差异具有统计学意义(P<0.05).结论 mf-ERG 显示叶黄素和玉米黄质治疗能有效提高ARMD患者mf-ERG的b波反应振幅密度,改善患眼视网膜光感受器功能.     

What is meso-zeaxanthin,and where does it come from?

The carotenoids lutein (L), zeaxanthin (Z), and meso-zeaxanthin (MZ) accumulate in the central retina, where they are collectively known as macular pigment (MP). Each of these three compounds exhibit a regional dominance, with MZ, Z, and L being the dominant carotenoids at the epicentre, mid-periphery, and periphery of the macula, respectively. There is a growing and evidence-based consensus that MP is important for optimal visual performance, because of its blue light-filtering properties and consequential attenuation of chromatic aberration, veiling luminance, and blue haze. It has also been hypothesised that MP may protect against age-related macular degeneration because of the same optical properties and also because of the antioxidant capacity of the three macular carotenoids. Challenges inherent in the separation and quantification of MZ have resulted in a paucity of data on the content of this carotenoid in foodstuffs, and have rendered the study of tissue concentrations of this compound problematic. As a consequence, the few studies that have investigated MZ have, perhaps, been disproportionately influential in the ongoing debate about the origins of this macular carotenoid. Certainly, the narrative that retinal MZ is derived wholly and solely from retinal L needs to be revisited.     

A role for the macular carotenoids in visual motor response

Abstract

Objectives

Lutein (L), zeaxanthin (Z), and meso-zeaxanthin are the dominant carotenoids within the central retina (there, termed macular pigment, MP). L is also the dominant carotenoid in the brain. The presence of L and Z in both motor and visual areas of the central nervous system is consistent with a role of these carotenoids in visual–motor behavior. The purpose of this study was to provide a first test of this hypothesis.

Methods

Balance ability (measured via the Standing Leg Test) and simple reaction time (measured via a stimulus appearing in one of four quadrants of a computer monitor) were measured in 49 subjects (mean age = 54.8 years). Fixed and variable reaction time, and coincidence anticipation ability (estimating the arrival of the stimulus at a target location moving at four velocities) were assessed in 106 younger subjects (mean age = 23 years) using a customized device. MP optical density was measured in all subjects via customized heterochromatic flicker photometry.

Results

MP optical density was significantly (P < 0.05) related to reaction time and to balance ability for the older subjects. Even for the younger group, MP optical density was significantly (P < 0.05) related to fixed and variable position reaction time, as well as coincidence anticipation errors, at high speed.

Discussion

L and Z status has been linked to benefits in cognitive function in past research. The present results, and the selective presence of L and Z in visual and motor areas in the brain, are consistent with these carotenoids having a role in visual and motor integration.     

Inhibitory effects of astaxanthin, β-cryptoxanthin,canthaxanthin, lutein,and zeaxanthin on cytochrome P450 enzyme activities

Astaxanthin, β-cryptoxanthin, canthaxanthin, lutein and zeaxanthin, the major xanthophylls, are widely used in food, medicine, and health care products. To date, no studies regarding the inhibitory effects of these xanthophylls on the nine CYPs isozymes have been reported. This study investigated the reversible and time-dependent inhibitory potentials of five xanthophylls on CYPs activities in vitro. The reversible inhibition results showed that the five compounds had only a weak inhibitory effect on the nine CYPs. Lutein did not inhibit the nine CYPs activities. Astaxanthin weakly inhibited CYP2C19, with an IC₅₀ of 16.2 μM; and β-cryptoxanthin weakly inhibited CYP2C8, with an IC₅₀ of 13.8 μM. In addition, canthaxanthin weakly inhibited CYP2C19 and CYP3A4/5, with IC₅₀ values of 10.9 and 13.9 μM, respectively. Zeaxanthin weakly inhibited CYP3A4/5, with an IC₅₀ of 15.5 μM. However, these IC₅₀ values were markedly greater than the C_max values reported in humans. No significant IC₅₀ shift was observed in the time-dependent inhibition screening. Based on these observations, it is unlikely that these five xanthophylls from the diet or nutritional supplements alter the pharmacokinetics of drugs metabolized by CYPs. These findings provide some useful information for the safe use of these five xanthophylls in clinical practice.     

万寿菊提取物缓解视疲劳作用的人体试食试验效果观察

目的研究万寿菊提取物对缓解视疲劳的作用。方法依据《保健食品功能学评价程序和检验方法》(2003年版)中缓解视疲劳的功能评价方法,采用自身对照及组间对照法,选择符合实验条件的志愿受试者120例,随机分为试验组和对照组,每组60人。试验组服用受试物,对照组服用安慰剂,用法与用量同试验组,连续服用45d。试验前后观察视疲劳症状积分、明视视久度、总有效率及远视力等指标。结果试验组的视疲劳症状积分由服用前的2.89±2.77降低至服用后的1.70±1.94(P<0.01);试食后试验组视疲劳症状积分与对照组比较差异有统计学意义(P<0.01);试验组明视持久度提高率为11.21±8.12%,与对照组(0.90±6.39%)比较,差异有统计学意义(P<0.01);试验组总有效率(55.56%)显著高于对照组的(7.84%)(P<0.01);试验组远视力提高幅度比试食前有显著改善(P<0.05)。结论万寿菊提取物能有效缓解人体视疲劳。     

益肾祛瘀汤对药物流产后生殖激素水平、阴道出血及月经的影响

目的 探讨益肾祛瘀汤对药物流(以下简称药流)后生殖激素水平、阴道出血及月经失调的影响及其作用机制.方法 将168例停经49 d内妊娠者随机分为3组.药流组56例,服米非司酮及米索前列醇药物流产;人工流产(以下简称人流)组56例,采用负压吸引术术终止妊娠;药流加中药组56例,药流方法同药流组,待孕囊排出后加服益肾祛瘀汤....     

Relationships between macular pigment optical density and cognitive function in unimpaired and mildly cognitively impaired older adults

Low carotenoid status (especially of the xanthophylls, lutein [L], and zeaxanthin [Z]) is common in older adults and has been associated with a number of degenerative diseases of the central nervous system ranging from retina (e.g., macular degeneration) to brain (e.g., Alzheimer's disease). In this study, we tested whether retinal measures of L + Z (macular pigment optical density [MPOD]), used as a surrogate for brain L + Z levels, were related to cognitive function when comparing healthy older adults with mildly cognitively impaired older adults. Twenty-four subjects with mild cognitive impairment were compared with 24 matched controls. Subjects were matched with respect to age, body mass index, ethnicity, sex, and smoking status. Degree of cognitive impairment and cognitive ability was determined via structured clinical interview. MPOD was measured psychophysically. In healthy older adults, MPOD was only related to visual-spatial and constructional abilities (p = 0.04). For subjects with mild cognitive impairment (MCI), however, MPOD was broadly related to cognition including the composite score on the mini-mental state examination (p = 0.02), visual-spatial and constructional abilities (p = 0.04), language ability (p = 0.05), attention (p = 0.03), and the total scale on the Repeatable Battery for the Assessment of Neuropsychological Status (p = 0.03). It is possible that L/Z status may be more strongly related to cognition when individuals are considered with established onset of cognitive decline.