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ABSTRACT: PURPOSE: Adipose tissue-associated chronic inflammation is involved in the pathogenesis of obesity-related diseases. Dietary fatty acids are known to influence inflammatory processes. The aim of this study was to investigate, whether diets with regular fat contents but variable fat qualities affect adipose tissue-associated inflammation through the fatty acid composition of mesenteric adipose tissue (MAT). METHODS: Obese Zucker rats were fed diets containing 7 % wt:wt rapeseed oil, corn oil, or lard for 10 weeks. Fatty acid composition and endocrine function regarding adipokines and cytokines of MAT, number of total CD3(+) T cells, and cytokine secretion of mesenteric lymph node (MLN)-derived lymphocytes were determined. Local effects in MAT and MLN were compared to systemic effects assessed in serum and peripheral blood mononuclear cells. RESULTS: Fatty acid composition of MAT reflected dietary fatty acid intake, without affecting endocrine function. Feeding the lard diet for 10 weeks increased the serum adiponectin and TNF-α secretion of blood lymphocytes, whereas CD3(+) T cells in blood were decreased. No effects were seen for the secretion of adipokines and cytokines from MAT, the amount of T cells in MLN, and cytokine secretion of MLN lymphocytes. CONCLUSIONS: In conclusion, feeding obese rats a diet with regular fat content but variable fat sources for 10 weeks, changed the fatty acid composition of MAT but not its secretory properties or MLN functions. Although the local immune system was not influenced, lard-feeding induced minor changes in systemic immune function.
European Journal of Nutrition 04/2013; · 2.75 Impact Factor
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ABSTRACT: The effect of polyphenol-rich cloudy apple juice (CloA) consumption on plasma parameters related to the obesity phenotype and potential effects of interactions between CloA and allelic variants in obesity candidate genes were assessed in obese men.
In this controlled, randomized, and parallel study, n = 68, non-smoking, non-diabetic men with a BMI ≥27 kg/m(2) received 750 mL/day CloA (802.5 mg polyphenols) or 750 mL/day control beverage (CB, isocaloric equivalent to CloA) for 4 weeks. Further, study participants were genotyped for single-nucleotide polymorphisms in PPARγ (rs1801282), UCP3 (rs1800849), IL-6 (rs1800795), FABP2 (rs1799883), INSIG2 (rs7566605), and PGC1 (rs8192678) genes. At the beginning and at the end of intervention plasma lipids, distinct adipokines and cytokines as well as anthropometric parameters were determined.
CloA compared to CB had no significant effect on plasma lipids, plasma adipokine and cytokine levels, BMI, and waist circumference. However, CloA consumption significantly reduced percent body fat compared to CB (∆ % body fat: CloA: -1.0 ± 1.3 vs. CB: -0.2 ± 0.9, p < 0.05). The IL-6-174 G/C polymorphism showed an interaction with body fat reduction induced by CloA. Solely in C/C, but not in G/C or G/G variants, a significant reduction in body fat after 4 weeks of CloA intervention was detectable.
The observed diet-gene interaction might be a first indication for the impact of individual genetic background on CloA-mediated bioactivity on obesity-associated comorbidities.
European Journal of Nutrition 10/2011; 51(7):841-50. · 2.75 Impact Factor
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ABSTRACT: This study aimed at developing a sensitive LC-MS/MS method for the quantification of sulforaphane (SFN) and indole-3-carbinol metabolites in plasma and urine after dietary intake of regular and selenium-fertilized broccoli using stable isotope dilution analysis. In a three-armed, placebo-controlled, randomized human intervention study with 76 healthy volunteers, 200 g of regular (485 μg of total glucosinolates and <0.01 μg of selenium per gram fresh weight) or selenium-fertilized broccoli (589 μg of total glucosinolates and 0.25 μg of selenium per gram fresh weight) was administered daily for 4 weeks. Glucoraphanin and glucobrassicin metabolites quantified in plasma and urine were SFN-glutathione, SFN-cysteine, SFN-cysteinylglycine, SFN-acetylcysteine, and indole-3-carboxaldehyde, indole-3-carboxylic acid, and ascorbigen, respectively. Dietary intake of selenium-fertilized broccoli increased serum selenium concentration analyzed by means of atomic absorption spectroscopy by up to 25% (p < 0.001), but affected neither glucosinolate concentrations in broccoli nor their metabolite concentrations in plasma and urine compared to regular broccoli.
Journal of Agricultural and Food Chemistry 08/2011; 59(15):8047-57. · 2.82 Impact Factor
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ABSTRACT: Oral intake of probiotic bacteria may beneficially modulate functions of NK cells. In healthy individuals, contradictory results exist as to whether NK cell functions can be modulated by probiotic bacteria. Therefore, the primary objective of our randomized, double-blind, placebo-controlled trial was to determine the effects of the probiotic strain Lactobacillus casei Shirota (LcS) on the activity of NK cells in healthy men who had been preselected for a reduced lytic function of their NK cells. Study participants (n = 68) were supplemented for 4 wk with a probiotic drink providing 1.95 × 10(10) CFU LcS/d or with a similar milk drink without probiotic additive. A run-in period of 2 wk preceded the probiotic supplementation followed by a 2-wk follow-up phase without the probiotic or control drink. Changes in the relative proportions of NK cells and other leukocytes as well as multiple functional measurements were determined longitudinally at baseline, after the 4-wk supplementation, and at the end of the follow-up. The probiotic supplementation had no significant effect on NK cell numbers and function or on phagocytosis, respiratory burst, or cytokine secretion of peripheral blood mononuclear cells. In conclusion, 4 wk of supplementation with LcS does not increase NK cell activity in healthy men with a reduced NK cell lytic activity. However, other doses of LcS, time of intervention, or differences, e.g. in the background diet, may result in a different outcome.
Journal of Nutrition 03/2011; 141(5):978-84. · 3.92 Impact Factor
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ABSTRACT: The organic food sales have been increasing during the recent years. It has been hypothesised that organically grown fruits are healthier based on their higher content of phytochemicals. However, data on the bioavailability of phytochemicals from organically or conventionally produced plant foods are scarce.
Two human intervention studies were performed to compare the bioavailability of polyphenols in healthy men after ingestion of apples from different farming systems. The administered apples were grown organically and conventionally under defined conditions and characterised regarding their polyphenol content and antioxidant capacity. No significant differences in the polyphenol content and the antioxidant capacity from the organic and conventional farming system were observed.
In the short-term intervention study, six men consumed either organically or conventionally produced apples in a randomized cross-over study. After intake of 1 kg apples, phloretin (C (max) 13 + or - 5 nmol/l, t (max) 1.7 + or - 1.2 h) and coumaric acid (C (max )35 + or - 12 nmol/l, t (max) 3.0 + or - 0.8 h) plasma concentrations increased significantly (P < 0.0001) in both intervention groups, without differences between the two farming systems. In the long-term intervention study, 43 healthy volunteers consumed organically or conventionally produced apples (500 g/day; 4 weeks) or no apples in a double-blind, randomized intervention study. In this study, 24 h after the last dosing regime, the apple intake did not result in increasing polyphenol concentrations in plasma and urine compared to the control group suggesting no accumulation of apple polyphenols or degradation products in humans.
Our study suggests that the two farming systems (organic/conventional) do not result in differences in the bioavailability of apple polyphenols.
European Journal of Nutrition 08/2010; 49(5):301-10. · 2.75 Impact Factor
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ABSTRACT: It is estimated that 75-85% of all chronic diseases are linked to lifestyle-related and environmental factors. The development of colon cancer is positively associated with obesity and inversely associated with the intake of dietary fibre, fruit and vegetable. Apple juice is the most widely consumed fruit beverage in Germany. It contains a specific spectrum of polyphenols and other components that may reduce the risk of colon cancer. Epidemiologic studies suggest an inverse correlation between apple consumption and colon cancer risk, although the mechanisms for these observations are not clear. The present review summarizes the preventive potential of apple juices and different apple constituents on biomarkers related to colon carcinogenesis with special focus on the in vivo evidence and the cancer promoting condition of obesity. However, under the cancer promoting condition of obesity, apple juice did not show cancer-preventive bioactivity. In our experiments a cancer-preventive bioactivity of apple juice is lacking in rats under the cancer-promoting condition of obesity. To further investigate, whether this lack of efficacy observed in obese rats might be representative for obese individuals human intervention studies on high risk groups such as obese or diabetic individuals are of interest and will be conducted.
Molecular Nutrition & Food Research 09/2009; 53(10):1289-302. · 4.30 Impact Factor
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ABSTRACT: The present study was performed to evaluate the polyphenol content and antioxidant capacity of apples (cv. ;Golden Delicious') grown under defined organic and conventional conditions. Apples were harvested at five comparable commercial farms over the course of three years (2004-2006). In 2005 and 2006 the antioxidant capacity was 15% higher (p < 0.05) in organically produced apples than in conventionally produced fruits. In 2005 significantly higher polyphenol concentrations were found in the organically grown apples. In 2004 and 2006 no significant differences were observed (2004, 304 +/- 68 microg/g organic vs 284 +/- 69 microg/g conventional, p = 0.18; 2005, 302 +/- 58 micro/g organic vs 253 +/- 41 microg/g conventional, p = 0.002; 2006, 402 +/- 100 microg/g organic vs 365 +/- 58 microg/g conventional, p = 0.17). Year-to-year variations in the antioxidant capacity and the polyphenol content of up to 20% were more significant than the production method found within one year. Finally, flavanols and flavonols were major determinants of the antioxidant capacities in these apples. Overall, the production method had a smaller impact on the variation in the polyphenol content and antioxidant capacity of apples than the yearly climate.
Journal of Agricultural and Food Chemistry 05/2009; 57(11):4598-605. · 2.82 Impact Factor
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ABSTRACT: Isoflavone intake is associated with various properties beneficial to human health which are related to their antioxidant activity, for example, to their ability to increase LDL oxidation resistance. However, the distribution of isoflavones among plasma lipoproteins has not yet been elucidated in vivo. Therefore, the objective of the present study was to investigate the association between daidzein (DAI) and lipoproteins in human plasma upon administration of the aglycone and glucoside form. Five men aged 22-30 years participated in a randomised, double-blind study in cross-over design. After ingestion of DAI and daidzein-7-O-beta-D-glucoside (DG) (1 mg DAI aglycone equivalents/kg body weight) blood samples were drawn before isoflavone administration as well as 1, 2, 3, 4.5, 6, 8, 10, 12, 24 and 48 h post-dose. Concentrations of DAI in the different lipoprotein fractions (chylomicrons, VLDL, LDL, HDL) and in the non-lipoprotein fraction were analysed using isotope dilution capillary GC/MS. The lipoprotein fraction profiles were similar for all subjects and resembled those obtained for plasma in our previously published study. The lipoprotein distribution based on the area under the concentration-time profiles from 0 h to infinity in the different fractions were irrespective of the administered form: non-lipoprotein fraction (53%) > LDL (20%) > HDL (14%) > VLDL (9.5%) > chylomicrons (2.5%). Of DAI present in plasma, 47 % was associated to lipoproteins. Concentrations in the different lipoprotein fractions as well as in the non-lipoprotein fraction were always higher after the ingestion of DG than of DAI. Taken together, these results demonstrate an association between isoflavones and plasma lipoproteins in vivo.
The British journal of nutrition 04/2009; 102(6):793-6. · 3.45 Impact Factor
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ABSTRACT: It has been hypothesised that organically grown vegetables are healthier than conventionally produced ones due to a higher content of phytochemicals. However, few data from controlled human studies exist. The aim of the present study was to compare the carotenoid content and antioxidant capacity of organically and conventionally produced carrots under defined conditions. Furthermore, a human intervention study was conducted to compare bioavailability, plasma antioxidant capacity, endogenous DNA strand breaks and immune parameters in healthy men ingesting carrots from different agricultural systems. Thirty-six volunteers consumed either organically or conventionally produced blanched carrots (200 g/d; 2 weeks) or no carrots in a double-blind, randomised intervention study. No statistically significant differences were observed in the total carotenoid contents (121 (sd 7) microg/g organic v. 116 (sd 13) microg/g conventional) and the antioxidant capacities (0.43 (sd 0.08) mumol Trolox equivalents/g organic v. 0.32 (sd 0.07) mumol Trolox equivalents/g conventional) of the carrots administered to the volunteers. Intake of organically or conventionally produced carrots significantly increased (P < 0.001) plasma alpha- and beta-carotene concentrations in both intervention groups without differences in plasma carotenoid concentrations. Consumption of carrots did not lead to significant changes in the plasma antioxidant status, endogenous DNA strand breaks and parameters of the immune system in all groups. Therefore, these results indicate that the agricultural system has neither an effect on the carotenoid content, the antioxidant capacity of carrots, nor on the bioavailability of carotenoids and on antioxidant, antigenotoxic and immunological effects as assessed in a human intervention study.
The British journal of nutrition 12/2008; 101(11):1664-72. · 3.45 Impact Factor
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ABSTRACT: The objective of the present study was to investigate the bioavailability and the configurational isomer distribution of the carotenoid astaxanthin (AST) in human plasma after ingestion of wild (Oncorhynchus spp.) and aquacultured (Salmo salar) salmon. In a randomised and double-blind trial, twenty-eight healthy men consumed 250 g wild or aquacultured salmon daily for 4 weeks which provided 5 mug AST/g salmon flesh. The plasma AST concentrations as well as the isomer distribution were measured by HPLC using a reversed and a chiral stationary phase. After 6 d of intervention with salmon, plasma AST concentrations reached a plateau of 39 nmol/l after consumption of wild salmon and of 52 nmol/l after administration of aquacultured salmon. At days 3, 6, 10 and 14 -- but not at day 28 -- the AST concentrations in human plasma were significantly greater after ingestion of aquacultured salmon. After administration of wild salmon, the (3S,3'S) isomer predominated in plasma (80 %), whereas after intake of aquacultured salmon the meso form (3R,3'S) prevailed (48 %). Therefore, the AST isomer pattern in human plasma resembles that of the ingested salmon. However, after consumption of both wild and aquacultured salmon for 28 d the relative proportion of the (3S,3'S) isomer was slightly higher and the (3R,3'R) form lower in human plasma compared with the isomer distribution in salmon flesh. A selective process of isomer absorption could be responsible for the observed differences in the relative proportions of the (3S,3'S) and (3R,3'R) isomers in human plasma compared with salmon flesh.
British Journal Of Nutrition 06/2008; 99(5):1048-54. · 3.01 Impact Factor
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ABSTRACT: There are conflicting results in the literature on the bioavailability of isoflavones in the aglycone and the glucoside forms.
The objective was to investigate the pharmacokinetics of the soy isoflavone daidzein (DAI) on oral administration of both the aglycone and glucoside form in a human intervention study. In addition, the pharmacokinetics of the bacterial and oxidative metabolites of DAI was assessed.
Seven German men aged 22-30 y participated in a randomized, double-blind study in a crossover design. After ingestion of pure DAI or pure daidzein-7-O-beta-d-glucoside (DG) (1 mg DAI aglycone equivalent/kg body weight), blood samples were drawn before isoflavone administration and 1, 2, 3, 4.5, 6, 8, 10, 12, 24, and 48 h after the dose. Urine was collected before and 0-6, 6-12, and 12-24 h after the intake of the isoflavones. The concentrations of DAI and its major bacterial and oxidative metabolites in plasma and urine were measured with isotope dilution capillary gas chromatography-mass spectrometry.
The systemic bioavailability (area under the curve; AUC(inf)), the maximal plasma concentration (C(max)), and the cumulative recovery of DAI in urine after administration of DG were 3-6 times greater than after the ingestion of DAI. Except for equol, which was formed by only one volunteer, all other quantified metabolites exhibited 2-12 times greater AUC(inf), C(max), and urinary recoveries after consumption of DG.
Our results show that DG exhibits a greater bioavailability than its aglycone when ingested in an isolated form.
American Journal of Clinical Nutrition 06/2008; 87(5):1314-23. · 6.67 Impact Factor
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ABSTRACT: Obesity and energy restriction modulate the development of precancerous aberrant crypt foci (ACF) in animal models of colon cancer.
Investigation of the major obesity-associated determinants for ACF-development and underlying mechanisms leading to ACF-modulation, such as changes in DNA damage or colonocytes hyperproliferation.
Lean and obese Zucker rats fed ad libitum (a.l.) or obese pair fed (p.f.) were induced with 1,2-dimethylhydrazine (DMH) for colon cancer. Multiple regression analyses were performed to identify major metabolic factors correlated with ACF number and size (aberrant crypts/ACF). DNA damage is analyzed by the comet-assay, epithelial proliferation by immunohistochemistry.
Aberrant crypt foci number was significantly elevated in Zucker obese a.l. (205.7+/-65.4 vs. lean 9.5+/-6.3, P<0.05) and is reduced by pair feeding in Zucker obese rats (81.4+/-28.5 vs. obese a.l., P<0.05). Compared to lean the ACF size was higher in Zucker obese a.l. (2.1+/-0.3 vs. lean 1.3+/-0.2., P<0.05) but is not reduced by pair feeding (1.7+/-0.2; P>0.05). While ACF number and size were modulated by genotype and/or pair feeding the DMH-induced DNA damage and hyperproliferation in colonocytes did not differ significantly between groups. Regression analysis showed that plasma parameters associated with lipid-metabolism (triglycerides, cholesterol, malondialdehyde) significantly correlated with the ACF number and size while parameters linked to carbohydrate-metabolism (glucose, insulin) were weaker determinants.
Obesity or pair feeding-associated modulation of ACF correlate with parameters related to lipid-metabolism but is not accompanied by changes in DNA damage and proliferation.
European Journal of Nutrition 04/2008; 47(3):161-70. · 2.75 Impact Factor
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ABSTRACT: The carotenoid zeaxanthin accumulates in the human macula lutea and protects retinal cells from blue light damage. However, zeaxanthin intake from food sources is low. Increasing zeaxanthin in common foods such as potatoes by traditional plant breeding or by genetic engineering could contribute to an increased intake of this carotenoid and, consequently, to a decreased risk of age-related macular degeneration. Our aim was to investigate whether zeaxanthin from genetically modified zeaxanthin-rich potatoes is bioavailable in humans. Three men participated in this randomized, controlled double-blinded, crossover pilot study. All subjects consumed 1,100 g of mashed potatoes, either genetically modified (Solanum tuberosum L. var. Baltica GM47/18; 3 mg zeaxanthin) or wild-type control potatoes (Solanum tuberosum L. var. Baltica; 0.14 mg zeaxanthin). A second treatment was followed after a 7-day wash-out period. The concentration of zeaxanthin was significantly increased in chylomicrons after consumption of genetically modified potatoes and 0.27 mg of the 3 mg zeaxanthin dose could be detected in chylomicrons. Consumption of control potatoes had no effect on concentrations of zeaxanthin in chylomicrons. After normalization of chylomicron zeaxanthin for plasma triacylglycerol, the time course of zeaxanthin concentrations peaked at 7 h after consumption of genetically modified potatoes. There were no significant differences in the concentrations of other major potato carotenoids such as lutein and beta-carotene in chylomicrons after consumption of genetically modified and wild type control potatoes. Thus, consumption of zeaxanthin-rich potatoes significantly increases chylomicron zeaxanthin concentrations suggesting that potentially such potatoes could be used as an important dietary source of zeaxanthin.
European Journal of Nutrition 04/2008; 47(2):99-103. · 2.75 Impact Factor
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ABSTRACT: High intakes of carotenoid-rich fruits and vegetables are associated with a reduced risk of various cancers including colon cancer. A human intervention study with carrot and tomato juice should show whether a diet rich in carotenoids, especially high in beta-carotene and lycopene, can modify luminal processes relevant to colon carcinogenesis. In a randomised cross-over trial, twenty-two healthy young men on a low-carotenoid diet consumed 330 ml tomato or carrot juice per d for 2 weeks. Intervention periods were preceded by 2-week depletion phases. At the end of each study period, faeces of twelve volunteers were collected for chemical analyses and use in cell-culture systems. Consumption of carrot juice led to a marked increase of beta-carotene and alpha-carotene in faeces and faecal water, as did lycopene after consumption of tomato juice. In the succeeding depletion phases, carotenoid contents in faeces and faecal water returned to their initial values. Faecal water showed high dose-dependent cytotoxic and anti-proliferative effects on colon adenocarcinoma cells (HT29). These effects were not markedly changed by carrot and tomato juice consumption. Neither bile acid concentrations nor activities of the bacterial enzymes beta-glucosidase and beta-glucuronidase in faecal water changed after carrot and tomato juice consumption. Faecal water pH decreased only after carrot juice consumption. SCFA were probably not responsible for this effect, as SCFA concentrations and profiles did not change significantly. In summary, in the present study, 2-week interventions with carotenoid-rich juices led only to minor changes in investigated luminal biomarkers relevant to colon carcinogenesis.
British Journal Of Nutrition 04/2008; 99(3):606-13. · 3.01 Impact Factor
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ABSTRACT: The present study was performed to compare the effects on antioxidant activity and on DNA damage of organic and conventionally produced apples grown under controlled conditions in human peripheral blood lymphocytes. Six healthy volunteers consumed either organically or conventionally grown apples (Golden Delicious, 1000 g) from two neighboring commercial farms in a double-blinded, randomized, cross-over study. The average content of total identified and quantified polyphenols in the organically and conventionally produced apples was 308 and 321 microg/g fresh weight, respectively. No statistically significant differences in the sum of phenolic compounds or in either of the polyphenol classes were found between the agricultural methods. Consumption of neither organically nor conventionally grown apples caused any changes in antioxidant capacity of low-density lipoproteins (lag time test), endogenous DNA strand breaks, Fpg protein-sensitive sites, or capacity to protect DNA against damage caused by hydrogen peroxide. However, a statistically significant decrease in the levels of endonuclease III sensitive sites and an increased capacity to protect DNA against damage induced by iron chloride were determined 24 h after consumption in both groups of either organic or conventionally grown apples, indicating the similar antigenotoxic potential of both organically and conventionally grown apples.
Journal of Agricultural and Food Chemistry 10/2007; 55(19):7716-21. · 2.82 Impact Factor
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ABSTRACT: As recently shown, a cloudy apple juice (CloA) was effective to modulate colon cancer associated parameters in rats treated with 1,2-dimethylhydrazine (DMH). To identify the bioactive substance classes in CloA, we fractionated CloA to yield a total polyphenol (PF) and a cloud (CF) fraction consisting of proteins, fatty acids, polyphenols, and cell wall polysaccharides. Rats received water (control (Cont)) or CloA, PF, and CF separate or combined (PF-CF) ad libitum for 7 weeks starting one week before the first DMH-injection. As determined by comet assay, the DMH-induced genotoxicity in colonocytes of controls (Cont/DMH: 7.7 +/- 0.5%) was significantly reduced by CloA (3.3 +/- 0.3%) but not by any of the fractions. The crypt cell proliferation induced by DMH (Cont/NaCl: 7.5 +/- 0.6%; Cont/DMH: 14.9 +/- 0.8%) was significantly decreased by CloA (9.4 +/- 0.4%), PF (12.4 +/- 0.7%), CF (11.6 +/- 0.4%), and PF-CF (12.4 +/- 0.6%). Although not statistically significant, CloA tended to reduce the number of large aberrant crypt foci (ACF) (Cont/DMH: 19.0 +/- 3.7; CloA/DMH: 12.3 +/- 1.9), while none of the fractions affected ACFs. Neither CloA nor the fractions changed mRNAs of colonic cyclooxygenases (COX-1, COX-2), glutathione-associated enzymes (GST-M2, gamma-GCS, GST-P), the splenocyte CD4/CD8 ratio, natural killer cell activity, and plasma antioxidant status. These results demonstrate that CloA had a higher cancer-preventive potential than the fractions and further, besides PF, identified CF as an additional bioactive fraction of CloA.
Journal of Agricultural and Food Chemistry 03/2007; 55(4):1181-7. · 2.82 Impact Factor
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ABSTRACT: Polyphenols are probably antigenotoxic on account of their antioxidant activities and might alter phase I and II enzymes in a way that results in chemoprotection. We investigated the hypothesis that polyphenols enhance expression of glutathione S-transferases (GSTs), which increases carcinogen detoxification and thereby provides protection against oxidative stress. HGSTP1 protein expression and GST polymorphisms were determined in leucocytes obtained during an intervention study with healthy subjects consuming two fruit juices in an 8 wk trial (polyphenol-free run in phase, juice intervention phase, washout phase, second juice intervention phase, each treatment regime lasted for 2 wk). The study had originally shown that juice intervention significantly reduced oxidative DNA damage in leucocytes at week 8 (Bub, A., Watzl, B., Blockhaus, M., Briviba, K. et al., J. Nutr. Biochem. 2003, 14, 90-98). We reanalysed the levels of DNA damage based on GST genotypes. We also treated leucocytes in vitro with mixtures of polyphenols and determined cytotoxicity and expression of 96 genes related to drug metabolism. Key results with leucocytes of the intervention study were that the initial content of hGSTP1 protein was first suppressed at weeks 4 and 6. At week 8, however, hGSTP1 protein expression was significantly increased. HGSTP1 protein levels and DNA damage were inversely correlated (p = 0.005), but there was no difference for cells obtained from subjects with hGSTM1*1 and hGSTM1*0 genotypes, nor was there any difference between cells from subjects consuming the two different juices. The treatment of leucocytes with polyphenol mixtures in vitro did not result in modulated GST gene expression or total GST activity, but in an up-regulation of other biotransformation enzymes (e. g., members of the cytochrome P450 and the sulphotransferase family). In conclusion, in vitro treatment of leucocytes led to a modulated mRNA expression of selected genes, not directly related to oxidative defence systems. In vivo, however, we observed a delayed enhancement of hGSTP1, which could be associated with an initial repression of oxidative DNA damage in leucocytes from human subjects, consuming juices with high levels of polyphenols.
Molecular Nutrition & Food Research 01/2007; 50(12):1191-200. · 4.30 Impact Factor
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ABSTRACT: Whether different intakes of vegetables and fruit modulate immunologic markers is currently not known.
We investigated the effects of low, medium, and high intakes of vegetables and fruit on markers of immune functions, including nonspecific markers of inflammation.
In a randomized controlled trial, nonsmoking men consumed a diet that included < or = 2 servings/d of vegetables and fruit for 4 wk. The subjects were then randomly assigned to 1 of 3 groups to consume 2 servings/d, 5 servings/d, or 8 servings/d of carotenoid-rich vegetables and fruit for another 4-wk period. Plasma concentrations of vitamins C and E and carotenoids were measured. The assessment of immunologic and inflammatory markers included the number and activity of natural killer cells, secretion of cytokines, lymphocyte proliferation, and plasma C-reactive protein concentrations.
The high intake (8 servings/d) of vegetables and fruit significantly increased total carotenoid concentrations in plasma compared with the low intake (2 servings/d; week 4 compared with week 8), whereas concentrations of vitamins C and E did not differ between week 4 and week 8. Immunologic markers were not significantly modulated. In contrast, C-reactive protein was significantly reduced at week 8 in the subjects who consumed 8 servings/d of vegetables and fruit compared with those who consumed 2 servings/d.
In healthy, well-nourished, nonsmoking men, 4 wk of low or high intakes of carotenoid-rich vegetables and fruit did not affect markers of immune function. However, a high intake of vegetables and fruit may reduce inflammatory processes, as indicated by the reduction of plasma C-reactive protein.
American Journal of Clinical Nutrition 12/2005; 82(5):1052-8. · 6.67 Impact Factor
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ABSTRACT: Appropriate animal models such as preruminant calves are necessary to study the complex physiological functions of carotenoids and to relate them to possible health effects in humans. In this study, the bioavailability and metabolism of lycopene from 2 dietary supplements were compared. LycoVit containing synthetic lycopene and Lyc-O-Mato containing natural tomato oleoresin were administered to 2 groups of preruminant calves (each n = 8) for 14 d in daily doses of 15 mg of lycopene. Plasma was analyzed for carotenoids before the intervention period, directly after, and each day for 5 d after the end of the intervention. All-trans and 5-cis lycopene, and 3 lycopene metabolites not previously found in calf plasma were detected. These metabolites contributed 52% of the total lycopene content measured at the end of the intervention period. Based on spectroscopic data, they might be hydrogenation products, which are formed from all-trans and/or 5-cis lycopene. In the LycoVit group, total lycopene concentrations were approximately 300% higher (286 +/- 89 nmol/L) than in the Lyc-O-Mato group (72 +/- 33 nmol/L) (P < 0.001). This indicates that, unlike in humans, lycopene from LycoVit and Lyc-O-Mato does not have equal bioavailabilities in preruminant calves. Therefore, the preruminant calf may not be a suitable animal model with which to study the biological and physiological effects of lycopene.
Journal of Nutrition 12/2005; 135(11):2616-21. · 3.92 Impact Factor
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ABSTRACT: The HDL-bound enzyme paraoxonase (PON) protects LDL from oxidation and may therefore attenuate the development of atherosclerosis. We examined the effect of tomato and carrot juice consumption on PON1 activity and lipid peroxidation in healthy young volunteers with different PON1-192 genotypes (Q/R substitution at position 192). In this randomized cross-over study twenty-two healthy, non-smoking men on a low-carotenoid diet received 330 ml/d tomato juice (37.0 mg lycopene, 1.6 mg beta-carotene) or carrot juice (27.1 mg beta-carotene, 13.1 mg alpha-carotene) for 2 weeks. Intervention periods were preceded by 2-week low-carotenoid intake. We determined the PON1-192 genotype by restriction fragment length polymorphism-polymerase chain reaction (RFLP-PCR) and measured ex vivo LDL oxidation (lag time), plasma malondialdehyde and PON1 activity at the beginning and end of each intervention period. At baseline, lag time was higher (P<0.05) in QQ (111 (sd 9) min) than in QR/RR subjects (101 (sd 8) min). Neither tomato nor carrot juice consumption had significant effects on PON1 activity. However, tomato juice consumption reduced (P<0.05) plasma malondialdehyde in QR/RR (Delta: -0.073 (sd 0.11) micromol/l) as compared to QQ subjects (Delta:+0.047 (sd 0.13) micromol/l). Carrot juice had no significant effect on malondialdehyde irrespective of the PON1-192 genotype. Male volunteers with the QR/RR genotype showed an increased lipid peroxidation at baseline. Although tomato and carrot juice fail to affect PON1 activity, tomato juice intake reduced lipid peroxidation in healthy volunteers carrying the R-allele of the PON1-192 genotype and could thus contribute to CVD risk reduction in these individuals.
British Journal Of Nutrition 04/2005; 93(3):291-7. · 3.01 Impact Factor
