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1.
Changes in Lutein Status Markers (Serum and Faecal Concentrations, Macular Pigment) in Response to a Lutein-Rich Fruit or Vegetable (Three Pieces/Day) Dietary Intervention in Normolipemic Subjects.
Olmedilla-Alonso, B, Rodríguez-Rodríguez, E, Beltrán-de-Miguel, B, Sánchez-Prieto, M, Estévez-Santiago, R
Nutrients. 2021;(10)
Abstract
Lutein is mainly supplied by dietary fruit and vegetables, and they are commonly jointly assessed in observational and interventional studies. Lutein bioavailability and health benefits depend on the food matrix. This study aimed to assess the effect of dietary intervention with lutein-rich fruit or vegetables on lutein status markers, including serum and faecal concentrations (by high pressure liquid chromatography), dietary intake (24 h recalls ×3), and macular pigment optical density (MPOD) and contrast threshold (CT) as visual outcomes. Twenty-nine healthy normolipemic subjects, aged 45-65 y, consumed 1.8 mg lutein/day supplied from fruits (14 subjects, 500 g/day of oranges, kiwi and avocados) or vegetables (15 subjects, 180 g/day of green beans, pumpkin, and sweet corn) for four weeks. Serum lutein concentration increased by 37%. The effect of the food group intervention was statistically significant for serum lutein+zeaxanthin concentration (p = 0.049). Serum α- and β-carotene were influenced by food type (p = 0.008 and p = 0.005, respectively), but not by time. Serum lutein/HDL-cholesterol level increased by 29% (total sample, p = 0.008). Lutein+zeaxanthin/HDL-cholesterol increased, and the intervention time and food group eaten had an effect (p = 0.024 and p = 0.010, respectively) which was higher in the vegetable group. The MPOD did not show variations, nor did it correlate with CT. According to correlation matrixes, serum lutein was mainly related to lutein+zeaxanthin expressed in relation to lipids, and MPOD with the vegetable group. In faecal samples, only lutein levels increased (p = 0.012). This study shows that a relatively low amount of lutein, supplied by fruit or vegetables, can have different responses in correlated status markers, and that a longer intervention period is needed to increase the MPOD. Therefore, further study with larger sample sizes is needed on the different responses in the lutein status markers and on food types and consumption patterns in the diet, and when lutein in a "pharmacological dose" is not taken to reduce a specific risk.
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2.
Development of a reference database for assessing dietary nitrate in vegetables.
Blekkenhorst, LC, Prince, RL, Ward, NC, Croft, KD, Lewis, JR, Devine, A, Shinde, S, Woodman, RJ, Hodgson, JM, Bondonno, CP
Molecular nutrition & food research. 2017;(8)
Abstract
SCOPE Nitrate from vegetables improves vascular health with short-term intake. Whether this translates into improved long-term health outcomes has yet to be investigated. To enable reliable analysis of nitrate intake from food records, there is a strong need for a comprehensive nitrate content of vegetables database. METHODS AND RESULTS A systematic literature search (1980-2016) was performed using Medline, Agricola and Commonwealth Agricultural Bureaux abstracts databases. The nitrate content of vegetables database contains 4237 records from 255 publications with data on 178 vegetables and 22 herbs and spices. The nitrate content of individual vegetables ranged from Chinese flat cabbage (median; range: 4240; 3004-6310 mg/kg FW) to corn (median; range: 12; 5-1091 mg/kg FW). The database was applied to estimate vegetable nitrate intake using 24-h dietary recalls (24-HDRs) and food frequency questionnaires (FFQs). Significant correlations were observed between urinary nitrate excretion and 24-HDR (r = 0.4, P = 0.013), between 24-HDR and 12 month FFQs (r = 0.5, P < 0.001) as well as two 4 week FFQs administered 8 weeks apart (r = 0.86, P < 0.001). CONCLUSION This comprehensive nitrate database allows quantification of dietary nitrate from a large variety of vegetables. It can be applied to dietary records to explore the associations between nitrate intake and health outcomes in human studies.
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3.
Short-term effects of a high nitrate diet on nitrate metabolism in healthy individuals.
Bondonno, CP, Liu, AH, Croft, KD, Ward, NC, Puddey, IB, Woodman, RJ, Hodgson, JM
Nutrients. 2015;(3):1906-15
Abstract
Dietary nitrate, through the enterosalivary nitrate-nitrite-NO pathway, can improve blood pressure and arterial stiffness. How long systemic nitrate and nitrite remain elevated following cessation of high nitrate intake is unknown. In 19 healthy men and women, the time for salivary and plasma nitrate and nitrite to return to baseline after 7 days increased nitrate intake from green leafy vegetables was determined. Salivary and plasma nitrate and nitrite was measured at baseline [D0], end of high nitrate diet [D7], day 9 [+2D], day 14 [+7D] and day 21 [+14D]. Urinary nitrite and nitrate was assessed at D7 and +14D. Increased dietary nitrate for 7 days resulted in a more than fourfold increase in saliva and plasma nitrate and nitrite (p < 0.001) measured at [D7]. At [+2D] plasma nitrite and nitrate had returned to baseline while saliva nitrate and nitrite were more than 1.5 times higher than at baseline levels. By [+7D] all metabolites had returned to baseline levels. The pattern of response was similar between men and women. Urinary nitrate and nitrate was sevenfold higher at D7 compared to +14D. These results suggest that daily ingestion of nitrate may be required to maintain the physiological changes associated with high nitrate intake.
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4.
The Glu298Asp single nucleotide polymorphism in the endothelial nitric oxide synthase gene differentially affects the vascular response to acute consumption of fruit and vegetable puree based drinks.
George, TW, Waroonphan, S, Niwat, C, Gordon, MH, Lovegrove, JA
Molecular nutrition & food research. 2012;(7):1014-24
Abstract
SCOPE Diets low in fruits and vegetables (FV) are responsible for 2.7 million deaths from cardiovascular diseases (CVD) and certain cancers annually. Many FV and their juices contain flavonoids, some of which increase endothelial nitric oxide synthase (eNOS) activity. A single nucleotide polymorphism in the eNOS gene, where thymine (T) replaces guanine (G) at position 894 predicting substitution of glutamate for aspartate at codon 298 (Glu298Asp), has been associated with increased CVD risk due to effects on nitric oxide synthesis and subsequently vascular reactivity. Individuals can be homozygous for guanine (GG), thymine (TT) or heterozygous (GT). METHODS AND RESULTS We investigated the effects of acute ingestion of a FV-puree-based-drink (FVPD) on vasodilation and antioxidant status in subjects retrospectively genotyped for this polymorphism. Healthy volunteers (n = 24; 11 GG, 11 GT, 2 TT) aged 30-70 were recruited to a randomized, controlled, crossover, acute study. We showed that acute consumption of 400 mL FVPD differentially affected individuals depending on their genotype. There was a significant genotype interaction for endothelium-dependent vasodilation measured by laser Doppler imaging with iontophoresis (P < 0.05) and ex vivo low-density lipoproteins (LDL) oxidation (P = 0.002). GG subjects had increased endothelium-dependent vasodilation 180 min (P = 0.028) and reduced ex vivo LDL oxidation (P = 0.013) after 60 min after FVPD compared with control, no differences were observed in GT subjects. CONCLUSION eNOS Glu298Asp genotype differentially affects vasodilation and ex vivo LDL oxidation after consumption of FV in the form of a puree-based drink.
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5.
Meal triacylglycerol profile modulates postprandial absorption of carotenoids in humans.
Goltz, SR, Campbell, WW, Chitchumroonchokchai, C, Failla, ML, Ferruzzi, MG
Molecular nutrition & food research. 2012;(6):866-77
Abstract
SCOPE Dietary lipids are considered to be primary potentiators of carotenoid absorption, yet the amount and source required to optimize bioavailability has not been systematically evaluated. The objective of this study was to examine the impact of both amount and source of triacylglycerols on postprandial absorption of carotenoids from vegetable salads. METHODS AND RESULTS Healthy subjects (n = 29) were randomized using a Latin square design (3 × 3) and consumed three identical salads with 3, 8, or 20 g of canola oil, soybean oil, or butter. Blood was collected from 0-10 h and triacylglycerol-rich fractions (TRLs) were isolated by ultracentrifugation. Carotenoid contents of TRL fractions were analyzed by HPLC-DAD. Considering all lipid sources, 20 g of lipid promoted higher absorption compared to 3 and 8 g for all carotenoid species (p < 0.05), except for α-carotene (p = 0.07). The source of lipid had less impact on the absorption of carotenoids than amount of lipid. Pooling results from all lipid amounts, monounsaturated fatty acid rich canola oil trended toward enhancing absorption of lutein and α-carotene compared to saturated fatty acid rich butter (p = 0.06 and p = 0.08, respectively). CONCLUSION While both amount and source of co-consumed lipid affect carotenoid bioavailability from vegetables, amount appears to exert a stronger effect.
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6.
Urinary excretion of flavonoids reflects even small changes in the dietary intake of fruits and vegetables.
Brevik, A, Rasmussen, SE, Drevon, CA, Andersen, LF
Cancer epidemiology, biomarkers & prevention : a publication of the American Association for Cancer Research, cosponsored by the American Society of Preventive Oncology. 2004;(5):843-9
Abstract
BACKGROUND Due to the random and systematic measurement errors associated with current dietary assessment instruments, there is a need to develop more objective methods of measuring the intake of foods of importance to human health. OBJECTIVE The purpose of this study was to test whether urinary excretion of flavonoids could be used to identify subjects who are meeting Norwegian recommendations for fruit and vegetable intake (5 servings per day) from individuals who are consuming the national average amount of fruits and vegetables (2 servings per day). DESIGN Twenty-four-hour urine samples were collected in a strict crossover controlled feeding study. Forty healthy subjects (19-34 years) were included in the study. After a 1-week run-in period, one group was given a controlled diet that included 2 servings (300 g) of fruits and vegetables daily for 14 days, while the other group was given a diet containing 5 servings (750 g) per day. Following a 2-week washout and a 1 week run-in period, the regimens were switched between the groups. RESULTS An increased intake of mixed fruits and vegetables from 2 to 5 servings per day significantly enhanced urinary excretion of eriodictyol, naringenin, hesperetin, quercetin, kaempferol, isorhamnetin, and tamarixetin. The citrus flavonoids naringenin and hesperetin showed a steep dose-response relationship to dietary intake of fruits and vegetables, whereas the association to eriodictyol, quercetin, kaempferol, isorhamnetin, and tamarixetin was more moderate. CONCLUSION The present study indicates that urinary excretion of dietary flavonoids may be used to assess changes of mixed fruit and vegetable intake corresponding to an increase from the present national intake in Norway to the recommended amount of 5 servings of fruits and vegetables daily.
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7.
Lymphocyte proliferation and apoptosis in HIV-seropositive and healthy subjects during long-term ingestion of fruit juices or a fruit-vegetable-concentrate rich in polyphenols and antioxidant vitamins.
Winkler, P, Ellinger, S, Boetzer, AM, Arendt, BM, Berthold, HK, Rockstroh, JK, Spengler, U, Goerlich, R
European journal of clinical nutrition. 2004;(2):317-25
Abstract
OBJECTIVE We investigated whether ingestion of polyphenols from fruit juices or a fruit-vegetable-concentrate affects lymphocyte proliferation and apoptosis in human immunodeficiency virus (HIV)-seropositive (HIV(+)) and HIV-seronegative (HIV(-)) subjects. DESIGN Randomized, prospective pilot intervention study. SETTING University of Bonn, Department of General Internal Medicine. SUBJECTS A total of 23 HIV(+) subjects from the HIV outpatient clinic, 18 HIV(-) controls. INTERVENTIONS Subjects ingested either 1 l of fruit juice or 30 ml of fruit-vegetable-concentrate daily for 16 weeks in addition to their regular diet. Lymphocyte proliferation and apoptosis were investigated in peripheral blood mononuclear cells at baseline, during 16-weeks of intervention, and after a 6-week washout. Proliferation was assessed by (3)H-thymidine incorporation and apoptosis by nuclear content as measured by flow cytometry. RESULTS Supplementation of fruit juices increased phytohemagglutinin-induced lymphocyte proliferation (mitotic index) in HIV(+) patients from 18+/-16 to 40+/-34 (P=0.004) and in healthy controls from 27+/-16 to 51+/-21 (P=0.016). Apoptosis was not affected in HIV(+) patients, but rose in healthy controls from 9+/-10 to 34+/-11 (apoptotic index; P=0.001). Intervention with concentrate did not significantly alter proliferation and apoptosis in HIV(+) and HIV(-) subjects. CONCLUSIONS Even though apoptosis did not change in HIV(+) subjects, ingestion of polyphenol-rich fruit juices might be favorable to HIV(+) patients due to enhanced proliferation, which could restore disturbances in T-cell homeostasis. In healthy controls, increased lymphocyte proliferation during juice consumption was counterbalanced by increased apoptosis.
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8.
Processing of vegetable-borne carotenoids in the human stomach and duodenum.
Tyssandier, V, Reboul, E, Dumas, JF, Bouteloup-Demange, C, Armand, M, Marcand, J, Sallas, M, Borel, P
American journal of physiology. Gastrointestinal and liver physiology. 2003;(6):G913-23
Abstract
Carotenoids are thought to diminish the incidence of certain degenerative diseases, but the mechanisms involved in their intestinal absorption are poorly understood. Our aim was to obtain basic data on the fate of carotenoids in the human stomach and duodenum. Ten healthy men were intragastrically fed three liquid test meals differing only in the vegetable added 3 wk apart and in a random order. They contained 40 g sunflower oil and mashed vegetables as the sole source of carotenoids. Tomato purée provided 10 mg lycopene as the main carotenoid, chopped spinach (10 mg lutein), and carrot purée (10 mg beta-carotene). Samples of stomach and duodenal contents and blood samples were collected at regular time intervals after meal intake. all-trans and cis carotenoids were assayed in stomach and duodenal contents, in the fat and aqueous phases of those contents, and in chylomicrons. The cis-trans beta-carotene and lycopene ratios did not significantly vary in the stomach during digestion. Carotenoids were recovered in the fat phase present in the stomach during digestion. The proportion of all-trans carotenoids found in the micellar phase of the duodenum was as follows (means +/- SE): lutein (5.6 +/- 0.4%), beta-carotene (4.7 +/- 0.3%), lycopene (2.0 +/- 0.2%). The proportion of 13-cis beta-carotene in the micellar phase was significantly higher (14.8 +/- 1.6%) than that of the all-trans isomer (4.7 +/- 0.3%). There was no significant variation in chylomicron lycopene after the tomato meal, whereas there was significant increase in chylomicron beta-carotene and lutein after the carrot and the spinach meals, respectively. There is no significant cis-trans isomerization of beta-carotene and lycopene in the human stomach. The stomach initiates the transfer of carotenoids from the vegetable matrix to the fat phase of the meal. Lycopene is less efficiently transferred to micelles than beta-carotene and lutein. The very small transfer of carotenoids from their vegetable matrices to micelles explains the poor bioavailability of these phytomicroconstituents.
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9.
Caffeic acid derivatives in artichoke extract are metabolised to phenolic acids in vivo.
Rechner, AR, Pannala, AS, Rice-Evans, CA
Free radical research. 2001;(2):195-202
Abstract
The purpose of this study was to investigate the absorption and metabolism of hydroxycinnamates from artichoke extract by determining the urinary excretion of the conjugates. Ten healthy, non smoking volunteers (5 female, 5 male) were given three capsules containing artichoke extract every 4 h (0, 4, 8 h) following two days of a low-polyphenol diet. One capsule contained 320 mg of artichoke extract equivalent to 34.3 +/- 0.6 mg/g hydroxycinnamates (caffeic acid derivatives) and 5.6 +/- 0.1 mg/g flavonoids. Polyphenols and phenolic acids present in the artichoke extract were not detected in the urine either as conjugates or aglycones. However, ferulic, isoferulic, dihydroferulic and vanillic acid were identified as major metabolites after beta-glucuronidase treatment of urine. The amount excreted as well as the ratio to that of creatinine, a biomarker for the general excretion rate, increased significantly on the study day compared to the pre-supplementation day. Thus, the caffeic acid esters found in the artichoke extract capsule are absorbed, metabolised and excreted as methylated phenolic acids such as ferulic, isoferulic, dihydroferulic and vanillic acid.
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10.
Plasma antioxidant capacity of HIV-seropositive and healthy subjects during long-term ingestion of fruit juices or a fruit-vegetable-concentrate containing antioxidant polyphenols.
Arendt, BM, Boetzer, AM, Lemoch, H, Winkler, P, Rockstroh, JK, Berthold, HK, Spengler, U, Goerlich, R
European journal of clinical nutrition. 2001;(9):786-92
Abstract
OBJECTIVE To investigate whether antioxidant polyphenols from fruit juices or a fruit-vegetable-concentrate increase the plasma antioxidant capacity in HIV-infected and healthy subjects. DESIGN Twenty-three HIV-seropositive and 18 seronegative adults were randomized to ingest either 1 l of fruit juice or 30 ml fruit-vegetable-concentrate per day over 16 weeks in addition to their normal Western diet. METHODS Plasma antioxidant capacity was determined as Trolox equivalent antioxidant capacity (TEAC) at baseline, after 1 and 16 weeks of intervention, and after a 6 week washout. RESULTS There was no difference in plasma antioxidant capacity between HIV-infected and healthy subjects at baseline (P=0.1). After 16 weeks of intervention TEAC increased in HIV-positive subjects with both types of polyphenol supplementation (juice, 1.38+/-0.07 to 1.42+/-0.04 mM, P=0.034; concentrate, 1.40+/-0.09 to 1.46+/-0.08 mM, P=0.025). TEAC was not altered by either type of supplementation in HIV-seronegative subjects. CONCLUSION Plasma antioxidant capacity can be increased by long-term ingestion of polyphenols from fruit juices or fruit-vegetable-concentrate in HIV-seropositive but not in HIV-seronegative subjects. SPONSORSHIP This study was supported by a grant and Cellagon aurum from HG Berner GmbH, Altenholz, and fruit juices from Eckes Granini GmbH & Co. KG, Nieder-Olm.