Oat (Avena sativa) Extract against Oxidative Stress-Induced Apoptosis in Human Keratinocytes.

Oat (Avena sativa) is well known for its various health benefits. The protective effect of oat extract against oxidative stress-induced apoptosis in human keratinocytes HaCaT was determined. First, extracts of two varieties of oat, Daeyang and Choyang, were analyzed for fat-soluble antioxidants such as α-tocotrienol, γ-oryzanols, lutein and zeaxanthin using an UPLC system and for antioxidant activity using a DPPH assay. Specifically, an 80% ethanol extract of Daeyang oat (Avena sativa cv. Daeyang), which had high amounts of antioxidants and potent radical scavenging activity, was further evaluated for protective effect against oxidative stress-induced cell death, intracellular reactive oxygen species levels, the phosphorylation of DNA damage mediating genes such as H2AX, checkpoint kinase 1 and 2, and p53 and the activation of apoptotic genes such as cleaved caspase-3 and 7 and poly (ADP-ribose) polymerase in HaCaT cells. The Daeyang and Choyang oat 80% ethanol extracts had 26.9 and 24.1 mg/100 g γ-oryzanols, 7.69 and 8.38 mg/100 g α-tocotrienol, 1.25 and 0.34 mg/100 g of lutein and 1.20 and 0.17 mg/100 g of zeaxanthin, respectively. The oat 80% ethanol extract treatment (Avena sativa cv. Daeyang) had a protective effect on oxidative stress-induced cell death in HaCaT cells. In addition, the oat 80% ethanol extracts led to a significant decrease in the intracellular ROS level at a concentration of 50-200 µg/mL, the attenuation of DNA damage mediating genes and the inhibition of apoptotic caspase activities in a dose dependent manner (50-200 µg/mL). Thus, the current study indicates that an oat (Avena sativa cv. Daeyang) extract rich in antioxidants, such as polyphenols, avenanthramides, γ-oryzanols, tocotrienols and carotenoids, has a protective role against oxidative stress-induced keratinocyte injuries and that oat may a useful source for oxidative stress-associated skin damage.

Black rice with giant embryo ameliorates serum C-reactive protein in adults with metabolic syndrome.

Metabolic syndrome is well known to increase the risk of cardiovascular diseases. We have reported that phytochemicals rich black rice with giant embryo reduced fat mass and metabolic disorders in an animal model. However, such effects have not been evaluated in humans. Subjects with metabolic syndrome (n = 49, 38 male, 44.3 ± 6.1 years) were randomly assigned into two groups and ingested roasted black-rice with giant embryo (BR, n = 26, 20 male) or white-rice (WR, n = 23, 18 male) powders mixed with water for breakfast for three months. Subjects were evaluated for various metabolic parameters before and after intervention. All parameters were not significantly different between groups before starting the intervention. After three months of consumption of either BR or WR, changes of body weight in BR vs WR groups (-1.54 kg vs -1.29 kg, p = 0.649) as well as waist circumference (-1.63 cm vs -1.02 cm, p = 0.365) were not significantly different between groups. However, changes in highly-sensitive C reactive proteins in BR vs WR groups (-0.110 mg/dl vs 0.017 mg/dl, p = 0.003) had significant differences. Three months of meal replacement with BR had a significant reduction of highly-sensitive C reactive protein compared to those with WR in adults with metabolic syndrome.

Enhanced Antioxidant Activity of Bioactives in Colored Grains by Nano-Carriers in Human Lens Epithelial Cells.

The use of phytochemicals for preventing chronic diseases associated with oxidative stress such as cataracts is hindered by their low bioavailability. The effects of nano-carriers on the antioxidant activities of extracts of black rice with giant embryo (BRGEx) and soybeans (SBx) have been determined in human lens epithelial B3 cells. Scanning (SEM) and transmission electron microscopy (TEM) demonstrated that rGO (reduced graphene oxide) has a flat surface unlike GO (graphene oxide), which has a distinctive wrinkled structure with defects. UPLC analysis revealed 41.9 µg/100 g of γ-oryzanols in water extract of BRGE, and 111.8 µg /100 g of lutein, 757.7 µg/100 g of γ-tocotrienol, 4071.4 µg/100 g of γ-tocopherol in 40% ethanol extract of soybeans, respectively. Even though a low concentration of BRGEx alone did not show any antioxidant activity in B3 cells, co-treatment of BRGEx with rGO together substantially reduced hydrogen peroxide and methylglyoxal-induced DNA damage, as determined by phosphorylated γH2AX. In addition, SBx with rGO also attenuated DNA damage. Furthermore, intracellular reactive oxygen species were significantly decreased by combining extracts of these colored grains with rGO. These results suggest a potential application of nanocarriers for enhancing the bioavailability of phytochemicals.

Identification of Enzymatic Cleavage Products of ß-Carotene-Rich Extracts of Kale and Biofortified Maize.

Provitamin A carotenoids in plant foods provide more than 80% of vitamin A intake for people in developing countries. Therefore, the conversion efficiency of ß-carotene to vitamin A is important, as it determines the effectiveness of plant foods as sources of vitamin A in humans. The objective of this study was to determine the effect of plant food antioxidants such as α-tocopherol, γ-tocopherol, α-tocotrienol, γ-tocotrienol and total γ-oryzanol on the cleavage of ß-carotene in vitro. Rat intestinal mucosa post mitochondrial fractions were incubated with ß-carotene-rich extracts of kale and biofortified maize for an hour at 37°C. Rat intestinal mucosa post mitochondrial fractions were also incubated with ß-carotene in the presence of either α-tocopherol, γ-tocopherol, α-tocotrienol, γ-tocotrienol or γ-oryzanol for 60 min at 37°C. The ß-carotene cleavage products were extracted and analyzed by an HPLC equipped with a C18 column at 340nm and 450nm. When ß-carotene alone was incubated without intestinal mucosa homogenate (control), no cleavage products were detected. When ß-carotene alone was incubated with intestinal mucosa homogenate, ß-apo-13-carotenone, ß-apo-14-carotenal, retinal, retinol and retinoic acid were formed. However, incubation of ß-carotene with either α-tocopherol, γ-tocopherol or α-tocotrienol resulted in a 10 fold inhibition of ß-apo-14-carotenal and ß-apo-13-carotenone formation. Antioxidant rich biofortified maize extract incubated with postmitochondrial fraction produced less ß-apo-13-carotenone compared to the kale extract. These results suggest that antioxidants inhibit the cleavage of ß-carotene and the formation of excentric cleavage products (ß-apo-13-carotenone, ß-apo-14-carotenal).

Targeting Reactive Carbonyl Species with Natural Sequestering Agents.

Reactive carbonyl species generated by the oxidation of polyunsaturated fatty acids and sugars are highly reactive due to their electrophilic nature, and are able to easily react with the nucleophilic sites of proteins as well as DNA causing cellular dysfunction. Levels of reactive carbonyl species and their reaction products have been reported to be elevated in various chronic diseases, including metabolic disorders and neurodegenerative diseases. In an effort to identify sequestering agents for reactive carbonyl species, various analytical techniques such as spectrophotometry, high performance liquid chromatography, western blot, and mass spectrometry have been utilized. In particular, recent advances using a novel high resolution mass spectrometry approach allows screening of complex mixtures such as natural products for their sequestering ability of reactive carbonyl species. To overcome the limited bioavailability and bioefficacy of natural products, new techniques using nanoparticles and nanocarriers may offer a new attractive strategy for increased in vivo utilization and targeted delivery of bioactives.

Elevated serum ferritin and mercury concentrations are associated with hypertension; analysis of the fourth and fifth Korea national health and nutrition examination survey (KNHANES IV-2, 3, 2008-2009 and V-1, 2010).

The impact of simultaneously elevated serum ferritin and mercury concentrations on hypertension in the general population is not known. To determine the association of serum ferritin and mercury concentrations with hypertension, 6213 subjects (3060 men and 3153 women) over 20 years of age from 2008 to 2010 Korea National Health and Nutrition Examination Survey were divided into tertiles according to serum ferritin and mercury concentrations in each gender. Serum ferritin (258.2 vs. 94.8 pmol/L) and mercury concentrations (28.4 vs. 19.9 nmol/L) were higher in men than in women. Serum ferritin (men; P = 0.029, women; P < 0.001) and mercury (men; P < 0.001, women; P = 0.003) concentrations were significantly associated with the prevalence of hypertension. In addition, significant correlation between serum ferritin and mercury concentrations in both men (r = 0.193, P < 0.001) and women (r = 0.145, P < 0.001) were found. Also, the increase of serum ferritin concentrations were more prominent in men (P < 0.001) than in women (P = 0.017) as the serum mercury tertiles increased after proper adjustments. Furthermore, significantly higher odds ratios of hypertension were found in the second (OR = 1.86, 95% CI; 1.05-3.30), and third (OR = 1.84, 95% CI; 1.01-3.36) tertiles of serum ferritin with the top tertile of serum mercury in men. The current study indicate that serum ferritin and mercury concentrations are associated with the prevalence of hypertension and that simultaneously elevated serum ferritin and mercury concentrations are related to the risk for hypertension in men.

Home Meal Replacement Fortified with Eggshell Powder and Vitamin D Prevents Bone Loss in Postmenopausal Women: A Randomized, Double-Blind, Controlled Study.

Calcium and vitamin D deficiencies have been ongoing problems in Koreans due to a lack of food sources of calcium and vitamin D. Postmenopausal women aged 50 to 64 years (n = 25) were randomly assigned to consume three home meal replacements (HMRs)/week with (treatment) and without (control) eggshell powder and vitamin D for 6 months. Additionally, subjects who agreed to continue the study consumed the same three HMRs/week for an additional 6 months in this randomized double-blind study. We confirmed the high compliance of the study participants by analyzing carotenoids, the bioactive substances of HMRs, in the blood. The treatment group consumed an additional 261 mg/d of calcium and 10.3 µg/d of vitamin D from the HMRs, thus meeting the recommended intakes of calcium and vitamin D for Koreans. As a result of consuming fortified HMRs for 6 months, the decline in femoral neck bone density was significantly reduced in the treatment group (p = 0.035). This study indicates that inexpensive eggshell powder may be a good source of calcium for populations with low consumption of milk and dairy products. Additionally, functional HMRs fortified with eggshell powder and vitamin D can be a good dietary strategy for bone health.

Lycopene supplementation modulates plasma concentrations and epididymal adipose tissue mRNA of leptin, resistin and IL-6 in diet-induced obese rats.

Obesity is characterised by chronic low-grade inflammation, and lycopene has been reported to display anti-inflammatory effects. However, it is not clear whether lycopene supplementation modulates adipokine levels in vivo in obesity. To determine whether lycopene supplementation can regulate adipokine expression in obesity, male Wistar rats were randomly assigned to receive a control diet (C, n 6) ora hyperenergetic diet (DIO, n 12) for 6 weeks. After this period, the DIO animals were randomised into two groups: DIO (n 6) and DIO supplemented with lycopene (DIO + L, n 6). The animals received maize oil (C and DIO) or lycopene (DIO + L, 10 mg/kg body weight(BW) per d) by oral administration for a 6-week period. The animals were then killed by decapitation, and blood samples and epididymal adipose tissue were collected for hormonal determination and gene expression evaluation (IL-6, monocyte chemoattractant protein-1(MCP-1), TNF-α, leptin and resistin). There was no detectable lycopene in the plasma of the C and DIO groups. However, the mean lycopene plasma concentration was 24 nmol in the DIO + L group. Although lycopene supplementation did not affect BW or adiposity, it significantly decreased leptin, resistin and IL-6 gene expression in epididymal adipose tissue and plasma concentrations. Also, it significantly reduced the gene expression of MCP-1 in epididymal adipose tissue. Lycopene affects adipokines by reducing leptin, resistin and plasma IL-6 levels. These data suggest that lycopene may be an effective strategy in reducing inflammation in obesity.

Retinoids, carotenoids, and tocopherols in breast adipose tissue and serum of benign breast disease and breast cancer patients.

Various retinoic acid (RA) isomers (all-trans, 13-cis, 11-cis, and 9-cis) as well as retinol, carotenoids, and tocopherol concentrations were determined in both serum and breast adipose tissue of 22 benign breast disease patients and 52 breast cancer patients categorized into 4 stages by malignancy. Serum RA isomers were analyzed by a newly developed sensitive method combining a high-performance liquid chromatography and a gas chromatography-mass spectrometry, and retinol, carotenoid, and tocopherol concentrations using a high-performance liquid chromatography system. The breast cancer patients showed significantly lower serum retinol, whereas significantly higher breast adipose tissue retinol concentration than those of benign breast disease patients. Although breast cancer patients showed significantly higher serum all-trans and 13-cis RA concentrations, 11-cis RA in breast adipose tissue was significantly lower in the breast cancer patients than those of benign breast disease patients and it was associated with the stage of malignancy. The current study indicates that the retinol and RA isomers in the target tissue of breast tumor patients are not reflecting their concentrations in circulation. The mechanisms of tissue specific uptake of RA isomers and their functions warrant further studies.

Effects of inhaled nitric oxide on oxidative stress and histopathological and inflammatory lung injury in a saline-lavaged rabbit model of acute lung injury.

BACKGROUND: Conventional mechanical ventilation (CMV) is fundamental in acute respiratory distress syndrome (ARDS) treatment. Inhaled nitric oxide (INO), an adjunctive therapy, has been used with ventilation in an attempt to improve oxygenation and reduce lung injury. OBJECTIVE: To analyze the early effects of low INO dose on oxygenation, oxidative stress, inflammatory, and histopathological lung injury in a rabbit model of acute lung injury (ALI). METHODS: This was a prospective, controlled, in vivo animal laboratory study. Forty rabbits were instrumented and ventilated at F(IO(2)) 1.0. ALI was induced by tracheal infusion of warm saline (30 mL/kg, 38°C) and lung oxidative stress was assessed by total antioxidant performance (TAP) assay. Animals were assigned to groups: control group (no. = 10, low tidal volume [V(T)] = 6 mL/kg, PEEP = 5 cm H(2)O), ALI without INO (no-INO group, no. = 10, low V(T) = 6 mL/kg, PEEP = 10 cm H(2)O), ALI plus INO (INO group, no. = 10, low V(T) = 6 mL/kg, PEEP = 10 cm H(2)O, INO = 5 ppm). Plateau pressure was limited to 30 cm H(2)O in all groups. Ten non-instrumented animals (healthy group) were studied for TAP assay. Ventilatory and hemodynamic parameters were recorded every 30 min for 4 hours. RESULTS: After lung injury, the instrumented groups were worse than the control group for P(aO(2)) (control group 438 ± 87 mm Hg, no-INO group 80 ± 13 mm Hg, INO group 81 ± 24 mm Hg, P < .001). The INO group showed decreased lung inflammation by leukocyte count in lung lavage fluid (no-INO group 4.8 ± 1.64, control group 0.16 ± 0.15, INO group 0.96 ± 0.35 polymorphonuclear cells × 10(6)/bronchoalveolar lavage fluid/lung, P < .001), decreased histopathological injury score (no-INO group 5 [range 1-16], INO group 2 [range 0-5], control group 0 [range 0-3], P < .001), and better lung protection against oxidative injury than the no-INO group (healthy group 68 ± 8.7, control group 66.4 ± 6.8, INO group 56.3 ± 5.1, no-INO group 45.9 ± 3.4 percent protection/g protein, P < .001). CONCLUSIONS: INO attenuates oxidative stress and histopathological and inflammatory lung injury in a saline-lavaged rabbit ALI model.

The carbonyl scavenger carnosine ameliorates dyslipidaemia and renal function in Zucker obese rats.

The metabolic syndrome is a risk factor that increases the risk for development of renal and vascular complications. This study addresses the effects of chronic administration of the endogenous dipeptide carnosine (ß-alanyl-L-histidine, L-CAR) and of its enantiomer (ß-alanyl-D-histidine, D-CAR) on hyperlipidaemia, hypertension, advanced glycation end products, advanced lipoxidation end products formation and development of nephropathy in the non-diabetic, Zucker obese rat. The Zucker rats received a daily dose of L-CAR or D-CAR (30 mg/kg in drinking water) for 24 weeks. Systolic blood pressure was recorded monthly. At the end of the treatment, plasma levels of triglycerides, total cholesterol, glucose, insulin, creatinine and urinary levels of total protein, albumin and creatinine were measured. Several indices of oxidative/carbonyl stress were also measured in plasma, urine and renal tissue. We found that both L- and D-CAR greatly reduced obese-related diseases in obese Zucker rat, by significantly restraining the development of dyslipidaemia, hypertension and renal injury, as demonstrated by both urinary parameters and electron microscopy examinations of renal tissue. Because the protective effect elicited by L- and D-CAR was almost superimposable, we conclude that the pharmacological action of L-CAR is not due to a pro-histaminic effect (D-CAR is not a precursor of histidine, since it is stable to peptidic hydrolysis), and prompted us to propose that some of the biological effects can be mediated by a direct carbonyl quenching mechanism.

Lutein and zeaxanthin supplementation reduces H2O2-induced oxidative damage in human lens epithelial cells.

PURPOSE: Epidemiological studies suggest that dietary intake of lutein and zeaxanthin is inversely related to the risk for senile cataract. The objectives of this work were to investigate the mechanisms by which these nutrients provide anti-cataract effects. We evaluated their modulation of oxidative damage in human lens epithelial cells (HLEC) and their interaction with intracellular glutathione (GSH). METHODS: Subconfluent HLEC were pre-incubated with or without 5 µM lutein, zeaxanthin, or α-tocopherol for 48 h and then exposed to 100 µM H(2)O(2) for 1 h. Levels of protein carbonyls in the cells were measured by western-blotting analysis following reaction with 2,4-dinitrophenylhydrazine (DNPH). Levels of malondialdehyde (MDA), reduced glutathione (GSH) and oxidized glutathione (GSSG) were measured by an HPLC system. DNA damage was assessed using comet assays. Cell viability was determined by 3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium (MTS) assay. RESULTS: In the absence of H(2)O(2), HLEC had very low levels of protein carbonyl and MDA. Supplementation with lutein, zeaxanthin, or α-tocopherol to the unstressed HLEC had no detectable effects on levels of oxidized proteins and lipid in the cells. Exposure of HLEC to H(2)O(2) significantly increased levels of oxidized proteins, lipid peroxidation, and DNA damage. Pre-incubation with lutein, zeaxanthin, or α-tocopherol dramatically reduced the levels of H(2)O(2) -induced protein carbonyl, MDA, and DNA damage in HLEC. The protective effects of lutein, zeaxanthin, and α-tocopherol against protein oxidation, lipid peroxidation, and DNA damage were comparable. Supplementation with lutein, zeaxanthin, or α-tocopherol increased GSH levels and GSH:GSSG ratio, particularly in response to oxidative stress. Depletion of GSH resulted in significant increase in susceptibility to H(2)O(2)-induced cell death. Supplementation with α-tocopherol, but not lutein or zeaxanthin, can partially restore the resistance of GSH-depleted cells to H(2)O(2). CONCLUSIONS: These data indicate that lutein or zeaxanthin supplementation protects lens protein, lipid, and DNA from oxidative damage and improves intracellular redox status upon oxidative stress. The protective effects are comparable to that of α-tocopherol, except that lutein and zeaxanthin cannot compensate for GSH depletion. The data imply that sufficient intake of lutein and zeaxanthin may reduce the risk for senile cataract via protecting the lens from oxidative damage.

Profiling histidine dipeptides in plasma and urine after ingesting beef, chicken or chicken broth in humans.

The in vitro metabolic stability of histidine-dipeptides (HD), carnosine (CAR) and anserine (ANS), in human serum, and their absorption kinetics after ingesting pure carnosine or HD rich foods in humans have been investigated. Healthy women (n = 4) went through four phases of taking one dose of either 450 mg of pure carnosine, 150 g beef (B), 150 g chicken (C), or chicken broth (CB) from 150 g chicken with a >2-week washout period between each phase. Blood samples were collected at 0, 30, 60, 100, 180, 240, and 300 min, and urine samples before and after (up to 7 h) ingesting pure carnosine or food. Both plasma and urine samples were analyzed for HD concentrations using a sensitive and selective LC-ESI-MS/MS method. CAR was undetectable in plasma after ingesting pure carnosine, B, C or CB. By contrast, plasma ANS concentration was significantly increased (P < 0.05) after ingesting C or CB, respectively. Urinary concentrations of both CAR and ANS were 13- to 14-fold increased after ingesting B, and 14.8- and 243-fold after CB ingestion, respectively. Thus, dietary HD, which are rapidly hydrolyzed by carnosinase in plasma, and excreted in urine, may act as reactive carbonyl species sequestering agents.

Chronic and acute effects of walnuts on antioxidant capacity and nutritional status in humans: a randomized, cross-over pilot study.

BACKGROUND: Compared with other common plant foods, walnuts (Juglans regia) are consistently ranked among the highest in antioxidant capacity. In vitro, walnut polyphenols inhibit plasma and LDL oxidation, while in animal models they lower biomarkers of oxidative stress and raise antioxidant capacity. A limited number of human feeding trials indicate that walnuts improve some measures of antioxidant status, but not others. METHODS: A 19 wk, randomized crossover trial was conducted in 21 generally healthy men and postmenopausal women > or = 50 y to study the dose-response effects of walnut intake on biomarkers of antioxidant activity, oxidative stress, and nutrient status. Subjects were randomized to receive either 21 or 42 g raw walnuts/d during each 6 wk intervention phase with a 6 wk washout between phases. Subjects were instructed to consume their usual diet, but refrain from eating any other tree nuts, seeds, peanuts, or ellagitannin-rich foods during the entire study, and other polyphenol-rich foods for 2 d prior to each study visit. RESULTS: Compared to baseline levels, red blood cell (RBC) linoleic acid and plasma pyridoxal phosphate (PLP) were significantly higher after 6 wk with 42 g/d walnuts (P < 0.05 for both). Overall, changes in plasma total thiols, and other antioxidant biomarkers, were not significant with either walnut dose. However, when compared to fasting levels, plasma total thiols were elevated within 1 h of walnut consumption with both doses during the baseline and end visits for each intervention phase (P < 0.05 for all). Despite the observed increase in RBC linoleic and linolenic acids associated with walnut consumption, this substrate for lipid peroxidation only minimally affected malondialdehyde (MDA) and antioxidant capacity. The proportional changes in MDA and Oxygen Radical Absorbance Capacity (ORAC) were consistent with a dose-response effect, although no significant within- or between-group differences were observed for these measures. CONCLUSIONS: Walnut consumption did not significantly change the plasma antioxidant capacity of healthy, well-nourished older adults in this pilot study. However, improvements in linoleic acid and pyridoxal phosphate were observed with chronic consumption, while total plasma thiols were enhanced acutely. Future studies investigating the antioxidant effects of walnuts in humans are warranted, but should include either a larger sample size or a controlled feeding intervention. TRIAL REGISTRATION: ClinicalTrials.gov: NCT00626691.

Total antioxidant performance is associated with diet and serum antioxidants in participants of the diet and physical activity substudy of the Jackson Heart Study.

Total antioxidant performance (TAP) measures antioxidant capacities in both hydrophilic and lipophilic compartments of serum and interactions known to exist between them. Our objective was to assess TAP levels in a subset of Jackson Heart Study (JHS) participants and to examine associations with dietary and total (diet + supplement) intakes of alpha-tocopherol, gamma-tocopherol (diet only), beta-carotene, vitamin C, fruit, vegetables, and nuts, and serum concentrations of alpha-tocopherol, gamma-tocopherol, and beta-carotene. We conducted a cross-sectional analysis of 420 (mean age 61 y; 254 women) African American men and women participating in the Diet and Physical Activity Sub-Study of the JHS in Jackson, Mississippi. In multivariate-adjusted models, we observed positive associations between total alpha-tocopherol, total and dietary beta-carotene, and total vitamin C intakes and TAP levels (P-trend < 0.05). Positive associations were also observed for vegetable, fruit, and total fruit and vegetable intakes (P-trend < 0.05). For serum antioxidant nutrients, alpha-tocopherol but not beta-carotene was associated with serum TAP levels. There were inverse associations for serum gamma-tocopherol and TAP levels. Associations for alpha-tocopherol were seen at intake levels much higher than the current Recommended Dietary Allowance. It may, therefore, be prudent to focus on increasing consumption of fruit, vegetables, nuts, and seeds to increase total antioxidant capacity.

A fluorometric assay to determine antioxidant activity of both hydrophilic and lipophilic components in plant foods.

This study aimed to develop a fluorometric method to determine total antioxidant activity of plant foods. The antioxidant activities in plant foods were determined after extracting (1) hydrophilic components with acidified methanol (methanol:glacial acetate acid:water=50:3.7:46.3), (2) lipophilic components with methanol followed by tetrahydrofuran (THF), or (3) both hydrophilic and lipophilic components using sequential extraction of acidified methanol and THF together. Both the hydrophilic assay [using the hydrophilic radical initiator 2,2'-azobis-(2-amidinopropane)dihydrochloride (10 mmol/L) and hydrophilic probe 2,7-dichlorodihydrofluorescein (DCFH)] and the lipophilic assay [using the lipophilic radical initiator [2,2'-azobis (4-methoxiy-2,4-dimethylvaleronitrile), 2 mmol/L], and the lipophilic probe 4,4-difluoro-5-(4-phenyl-1,3-butadienyl)-4-bora-3a,4a-diaza-s-indacene-3-undecanoic acid (C11-BODIPY 581/591) (BODIPY: 2 micromol/L)] were used to measure antioxidant activity. The inhibition of BODIPY oxidation was significantly increased (P<.01) when both the hydrophilic and lipophilic components were extracted using acidified methanol and organic solvent as compared to those extracted by organic solvent alone. In addition, the rate of DCFH oxidation was significantly delayed (P<.05) when both components coexisted compared to DCFH oxidation of the hydrophilic component alone. The combination of lipophilic and hydrophilic components in these plant foods showed significantly greater antioxidant activity than that of either hydrophilic or lipophilic component alone. Thus, both hydrophilic and lipophilic components in plant foods and their interactions should be considered when determining their antioxidant activity.

Plasma levels of retinoids, carotenoids and tocopherols in patients with mild obstructive sleep apnoea.

BACKGROUND AND OBJECTIVE: OSA is associated with increased incidence of cardiovascular diseases. Pathogenic mechanisms of vascular diseases include thickened vascular walls due to the increased number of smooth muscle cells (SMC). Retinoic acid (RA) suppresses the growth of SMC, and reduced retinoid levels are associated with vascular diseases. Oxidant signalling promotes SMC growth, thus antioxidant levels may also influence the development of cardiovascular diseases. The present study tested the hypothesis that plasmas from OSA patients contain altered levels of retinoids, carotenoids and tocopherols. METHODS: Plasma samples were taken before and after sleep from patients with OSA (mostly mild) without known cardiovascular diseases and from control subjects. Levels of retinoids, carotenoids and tocopherols were measured using sensitive gas chromatograph-mass spectrometry and high pressure liquid chromatography methods and total antioxidant capacity was assessed fluorometrically. RESULTS: Results showed that plasmas from patients with OSA had significantly lower retinyl palmitate and 9-cis RA compared with control subjects, while levels of retinol, all-trans RA and 13-cis RA were indifferent. All-transbeta-carotene and 9-cisbeta-carotene were also lower in OSA patients. Levels of all-trans RA and 13-cis RA in OSA patients were reduced after sleep compared with before sleep. OSA patients showed significantly higher delta-tocopherol compared with controls. Treatment of cultured human vascular SMC with post-sleep OSA patient plasmas promoted cell growth, but not in controls. CONCLUSIONS: Mild OSA exhibits altered levels of specific retinoids, carotenoids and tocopherols, which may be markers and/or mediators for the increased susceptibility of patients to vascular diseases.

Determination of 9-cis beta-carotene and zeta-carotene in biological samples.

Concentrations of 9-cis beta-carotene (9-cis betaC) and zeta-carotene (zetaC) in biological samples may provide crucial information on the biological activities of these carotenoids. However, in high-performance liquid chromatography (HPLC) these carotenoids are often co-eluted. Therefore, there is an urgent need to develop a method for 9-cis betaC and zetaC quantitation. Both 9-cis betaC and zetaC have peak absorbance at 400 and 450 nm, respectively, whereas only 9-cis betaC has peak absorbance at 475 nm. We developed a HPLC method to quantitate 9-cis betaC and zetaC by using peak absorbance ratios. The 9-cis betaC/zetaC peak area was monitored at 475, 450 and 400 nm. The 9-cis betaC was quantified by using absorbance value at 475 nm; zetaC was then calculated from the 9-cis betaC/zetaC peak at 400 nm by subtracting 9-cis betaC contribution at 400 nm using the 400-nm/475-nm peak absorbance ratio of 9-cis betaC (0.39). This method was applied to determine 9-cis betaC and zetaC concentrations in serum and breast milk samples (n=12) from American lactating women and serum and breast adipose tissue samples (n=16) from Korean women with either benign or malignant breast tumors. 9-cis betaC concentrations in serum and breast milk of American women, and serum and adipose tissue of Korean women were 7.1+/-0.8 and 1.1+/-0.2 nM, and 15.6+/-1.1 nM and 0.2+/-0.1 nmol/g, respectively. zetaC concentrations in the above samples were 54.2+/-7.2 and 8.3+/-1.8 nM, and 49.0+/-3.9 nM and 0.3+/-0.1 nmol/g, respectively.

Determination of carotenoids in yellow maize, the effects of saponification and food preparations.

Maize is an important staple food consumed by millions of people in many countries. Yellow maize naturally contains carotenoids which not only provide provitamin A carotenoids but also xanthophylls, which are known to be important for eye health. This study was aimed at 1) evaluating the effect of saponification during extraction of yellow maize carotenoids, 2) determining the major carotenoids in 36 genotypes of yellow maize by high-performance liquid chromatography with a C30 column, and 3) determining the effect of cooking on the carotenoid content of yellow maize. The major carotenoids in yellow maize were identified as all-trans lutein, cis-isomers of lutein, all-trans zeaxanthin, alpha- and beta-cryptoxanthin, all-trans beta-carotene, 9-cis beta-carotene, and 13-cis beta-carotene. Our results indicated that carotenoid extraction without saponification showed a significantly higher yield than that obtained using saponification. Results of the current study indicate that yellow maize is a good source of provitamin A carotenoids and xanthophylls. Cooking by boiling yellow maize at 100 degrees C for 30 minutes increased the carotenoid concentration, while baking at 450 degrees F for 25 minutes decreased the carotenoid concentrations by almost 70% as compared to the uncooked yellow maize flour.

Fat Mass Is Associated with Serum 25-Hydroxyvitamin D Concentration Regardless of Body Size in Men.

There are no large community-based studies examining the association of body size vs. body fat with vitamin D status. Association of serum 25-hydroxyvitamin D (25OHD) with body weight and subcategories of body weight defined by fat mass were evaluated in a large, free living population. Out of a total of 29,235 subjects from the 2008⁻2010 Korean National Health and Nutrition Examination Survey, the relevant data included 6458 subjects over 50 years of age who were analyzed cross-sectionally. Serum 25OHD concentrations were compared in men (n = 3164) and in women (n = 3294) by tertiles of body weight and body fat mass, as measured by Dual-energy X-ray Absorptiometry (DXA) within sex-specific tertiles of body weight. Serum 25OHD was weakly inversely correlated with body weight in the men and the women after adjustment for age (r = −0.075 and −0.073, respectively, p < 0.001 for both). Within each tertile of body weight, serum 25OHD decreased progressively as fat mass increased in men. This pattern was similar in the women but not consistently significant. Whereas body weight predicted a small decrease in serum 25OHD in the men and the women, greater adiposity, for any given weight, predicted larger decreases in the men, but not consistently in women.