Beta carotene uptake into atherosclerotic plaque: Enhanced staining and preferential ablation with the pulsed dye laser

The yellow color of atherosclerotic plaque is due to the presence of carotenoids, which absorb light between 430–530 nm and account for the preferential ablation of plaque by the pulsed dye laser operating at 480 nm. This study was designed to examine tissue uptake of β-carotene and the effect of uptake on arterial plaque ablation. Forty-two atherosclerotic NZW rabbits were given intravenous β-carotene at a dose of 40 mg/kg, twice weekly and killed between 1 hour and 28 days after the initial injection. β-carotene was not detected in control specimens but was significantly greater in plaque than in normal wall at all time points following β-carotene injection (P < 0.04 Mann Whitney U test). The ablation threshold was significantly lower in β-carotene treated plaque than in untreated plaque or normal arterial wall (P < 0.01, Fisher's exact test). In this model β-carotene is preferentially taken up into arterial plaque, resulting in increased absorption of laser radiation at 480 nm and enhanced tissue ablation. © 1993 Wiley-Liss, Inc.     

A Randomized Study of Nutritional Supplementation in Patients with Unilateral Wet Age-Related Macular Degeneration

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.     

Vitamin A Status Improvement in Obesity: Findings and Perspectives Using Encapsulation Techniques

The association between obesity and vitamin A has been studied. Some studies point to the anti-obesity activity related to this vitamin, carotenoids with provitamin A activity, and carotenoid conversion products. This performance has been evaluated in respect of adipogenesis, metabolic activity, oxidation processes, secretory function, and oxidative stress modulation, showing a new property attributed to vitamin A in preventing and treating obesity. However, vitamin A and its precursors are highly sensitive and easily degraded when subjected to heat, the presence of light, and oxygen, in addition to losses related to the processes of digestion and absorption. In this context, encapsulation presents itself as an alternative capable of increasing vitamin A’s stability in the face of unfavorable conditions in the environment, which can reduce its functionality. Considering that vitamin A’s status shows a strong correlation with obesity and is an innovative theme, this article addresses the associations between vitamin A’s consumption and its precursors, encapsulated or not, and its physiological effects on obesity. The present narrative review points out those recent studies that demonstrate that vitamin A and its encapsulated precursors have the most preserved functionality, which guarantees better effects on obesity therapy.     

类胡萝卜素和维甲酸对不同雌激素状态乳腺癌细胞增殖的影响

目的：通过体外细胞研究,观察类胡萝卜素和维甲酸对人乳腺癌细胞的作用。方法：用噻唑蓝（MTT）法观察维甲酸和类胡萝卜素对体外培养的雌激素受体阳性（ER＋）乳腺癌细胞MCF－7和雌激素受体阴性（ER－）乳腺癌细胞MDA－MB－435S的抑制作用。结果：发现维甲酸和类胡萝卜素对乳腺癌细胞的增殖抑制表现出剂量、时间和结构效应以及细胞的特异性。其中β-胡萝卜素对ER＋和ER－乳腺癌细胞均有很强的抑制作用,而维甲酸和其他4种类胡萝卜素（玉米黄素、虾青素、角黄素、玉米黄素双棕榈酸酯）对ER＋乳腺癌细胞的抑制作用强于ER－乳腺癌细胞。结论：β－胡萝卜素对乳腺癌细胞的抑制机制不同于维甲酸和其他4种类胡萝卜素,也不需转化为维甲酸而起作用。     

Dietary retinoids and carotenoids in rodent models of mammary tumorigenesis

In this review of the scientific literature the relationship between retinoids, carotenoids, and mammary carcinogenesis is examined. Several retinoids have shown promise as chemopreventive agents against chemically induced mammary carcinogenesis in mice and especially in rats. The most promising retinoids are retinyl acetate (RA) and N-(4-hydroxyphenyl)retinamide (4-HPR, fenretinide). In rats, dietary administration of these retinoids reduced tumor incidence and multiplicity, and increased the latency of DMBA or MNU-induced mammary cancers. In mice, 4-HPR reduced the number of hyperplastic alveolar nodules and the number of tumors in MTV- and MTV+ mice, respectively. Among retinoids, 4-HPR is at present the most promising analogue, due to its ability to concentrate in the mammary gland. The combination of 4-HPR with tamoxifen not only is more effective in suppressing breast cancer than either agent alone, but also inhibits the appearance of subsequent cancers following the surgical removal of the first tumor. These studies suggest that retinoids, like tamoxifen, may be applicable to the prevention of contralateral breast cancer in women who underwent breast cancer surgery. It is also becoming evident that differentiation therapy and chemoprevention can become attractive alternative approaches to intensive cytotoxic chemotherapy. The role of carotenoids in the prevention of mammary carcinogenesis, however, is ambiguous. Poor absorption and low levels of carotenoids that reach the target tissues complicate interpretation of data in rodent models of mammary carcinogenesis. Very few animal studies are presently available in which purified carotenoids were found effective against mammary carcinogenesis. These results do not justify undertaking clinical evaluation of individual carotenoids against breast cancer at this time.     

天然红心蛋中类胡萝卜素提纯物对人肝癌细胞增殖和凋亡的影响

目的:探讨天然红心蛋中类胡萝卜素提纯物(carotenoidsextractsfromnaturalredyolk,CENRY)对人肝癌细胞QGY-7703细胞增殖和凋亡的影响。方法:采用体外培养,细胞增殖实验,激光扫描共聚焦显微镜(LSCM)观察细胞形态及钙离子浓度变化,采用流式细胞术检测细胞周期等。结果:CENRY1.0、0.5、0.25μmol/L三个剂量能显著抑制人肝癌QGY-7703细胞增殖,细胞凋亡指数随剂量增加及时间延长而上升;CENRY对QGY-7703细胞存在G2/M期阻滞作用;处理组细胞内Ca2+浓度极显著地升高。结论:CENRY能抑制QGY-7703增殖、诱导凋亡。     

运用共振拉曼散射光谱法测定皮肤类胡萝卜素

[目的]用共振拉曼散射光谱法测试皮肤类胡萝卜素水平,观察机体类胡萝卜素变化情况。[方法]120名成年受试者按照其年龄、性别和试验前皮肤类胡萝卜素指数配对后,随机分为试验组和对照组。试验组人群每天补充β-胡萝卜素12.6mg,共8周。两组人群在试验前、试验第4周末和第8周末,分别运用共振拉曼散射光谱测试受试者皮肤类胡萝卜素,观察皮肤中类胡萝卜素水平变化情况。同时进行膳食调查,了解膳食摄入情况。[结果]试食组人群补充β-胡萝卜素第4周时皮肤类胡萝卜素指数比试验前的基础值上升了24.3%、第8周时比试验前的基础值上升了44.0%,且与对照人群相比差异有统计学意义(P<0.001)。[结论]由于两组人群在试验期间的膳食摄入情况没有差异,实验中试食组人群皮肤类胡萝卜素指数的增高可认为与补充β-胡萝卜素有关。共振拉曼散射光谱作为一种非创伤性的检测方法,可用于反映皮肤类胡萝卜素水平,进而提示机体类胡萝卜素的营养状况。     

Biochemical Validation of the Older Australian’s Food Frequency Questionnaire Using Carotenoids and Vitamin E

Background: Validation of a food frequency questionnaire (FFQ) is important, as inaccurate and imprecise information may affect the association between dietary exposure and health outcomes. Objective: This study assessed the validity of the Older Australian’s FFQ against plasma carotenoids and Vitamin E. Methods: A random subsample (n = 150) of 2420 participants in the Hunter Community Study, aged 55–85 years, were included. Correlations between crude and energy-adjusted FFQ estimates of carotenoids, Vitamin E, and fruit and vegetables with corresponding biomarkers were determined. Percentages of participants correctly classified in the same quartile, and in the same ± 1 quartile, by the two methods were calculated. Results: Significant correlations (P < 0.05) were observed for α-carotene (r = 0.26–0.28), β-carotene (r = 0.21–0.25), and β-cryptoxanthin (r = 0.21–0.23). Intakes of fruits and vegetables also showed similar correlations with these plasma carotenoids. Lycopene was only significantly correlated with fruit and vegetable intakes (r = 0.19–0.23). Weak correlations were observed for lutein + zeaxanthin (r = 0.12–0.16). For Vitamin E, significant correlation was observed for energy-adjusted FFQ estimate and biomarker (r = 0.20). More than 68% of individuals were correctly classified within the same or adjacent quartile, except for lutein + zeaxanthin. Conclusion: With the exception of lutein + zeaxanthin, the Older Australian’s FFQ provides reasonable rankings for individuals according to their carotenoids, Vitamin E, fruit and vegetable intakes.     

Amino acids,major carotenoids and vitamin A activity of some traditional sauces consumed in the Far North Region of Cameroon

The aim of this study was to determine the amino acids major carotenoids and vitamin A activity in the 22 most frequently consumed traditional sauces in the Far North Region of Cameroon. Results showed that the most abundant amino acids in all sauces were glumatic acid (119–192 mg/g protein), aspartic acid (61.3–132 mg/g protein), leucine (34.5–99.2 mg/g protein) and phenylalanine (22.1–64.3 mg/g protein). High levels of amino acids were found in Gouboudou. Essential amino acids in most of the sauces represented up to 33% of total amino acids, indicating a good equilibrium between amino acids. Essential amino acids in most of these sauces met the recommended children requirement of the FAO/WHO/UNU for children 1–2 years old, except methionine and cysteine. Methionine + cysteine and lysine were the limiting amino acids in these sauces. Carotenoids and vitamin A activity (0.02–0.15 mg retinol activity equivalents/100 g dry weight) were present only in small quantities in all sauces when compared with other African sauces.     

Fruit,Vegetable and Dietary Carotenoid Intakes Explain Variation in Skin-Color in Young Caucasian Women: A Cross-Sectional Study

Fruit and vegetables contain carotenoid pigments, which accumulate in human skin, contributing to its yellowness. This effect has a beneficial impact on appearance. The aim was to evaluate associations between diet (fruit, vegetable and dietary carotenoid intakes) and skin color in young women. Ninety-one Caucasian women (Median and Interquartile Range (IQR) age 22.1 (18.1–29.1) years, BMI 22.9 (18.5–31.9) kg/m²) were recruited from the Hunter region (Australia). Fruit, vegetable and dietary carotenoid intakes were estimated by a validated food frequency questionnaire. Skin color was measured at nine body locations (sun exposed and unexposed sites) using spectrophotometry. Multiple linear regression was used to assess the relationship between fruit and vegetable intakes and skin yellowness adjusting for known confounders. Higher combined fruit and vegetable intakes (β = 0.8, p = 0.017) were associated with higher overall skin yellowness values. Higher fruit combined fruit and vegetable intakes (β = 1.0, p = 0.004) were associated with increased unexposed skin yellowness. Combined fruit and vegetables plus dietary carotenoid intakes contribute to skin yellowness in young Caucasian women. Evaluation of interventions using improvements in appearance as an incentive for increasing fruit and vegetable consumption in young women is warranted.