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The authors acknowledge J. David, C. Prolhac, D. Durand and the personnel of the Animal Facility (C. de L’Homme, B. Cohade) for technical assistance; PurposeIn the present study, we aimed to metabolically characterize the postprandial adaptations of the major tissues involved in energy, lipids and amino acids metabolisms in mini-pigs.MethodMini-pigs were fed on high-fat–high-sucrose (HFHS) diet for 2 months and several tissues explored for metabolic analyses. Further, the urine metabolome was followed over the time to picture the metabolic adaptations occurring at the whole body level following overfeeding.ResultsAfter 2 months of HFHS consumption, mini-pigs displayed an obese phenotype characterized by high circulating insulin, triglycerides and cholesterol levels. At the tissue level, a general (muscle, adipose tissue, intestine) reduction in the capacity to phosphorylate glucose was observed. This was also supported by the enhanced hepatic gluconeogenesis potential, despite the concomitant normoglycaemia, suggesting that the high circulating insulin levels would be enough to maintain glucose homoeostasis. The HFHS feeding also resulted in a reduced capacity of two other pathways: the de novo lipogenesis, and the ranched-chain amino acids transamination. Finally, the follow-up of the urine metabolome over the time allowed determining breaking points in the metabolic trajectory of the animals.ConclusionsSeveral features confirmed the pertinence of the animal model, including increased body weight, adi-posity and porcine obesity index. At the metabolic level,we observed a perturbed glucose and amino acid metabolism, known to be related to the onset of the obesity. The urine metabolome analyses revealed several metabolic pathways potentially involved in the obesity onset, including TCA (citrate, pantothenic acid), amino acids catabolism (cysteine, threonine, leucine).

Supplemental Material can be found at: http://jn.nutrition.org/cgi/content/full/jn.108.103655/DC1 Publication Inra prise en compte dans l'analyse bibliométrique des publications scientifiques mondiales sur les Fruits, les Légumes et la Pomme de terre. Période 2000-2012. http://prodinra.inra.fr/record/256699; International audience; Epidemiological studies have suggested that high consumption of tomato products is associated with a lower risk for chronic diseases. To exert their health effect, the phytochemicals of tomatoes have to be bioavailable and therefore it implies their stability through the digestion process. Here, we assessed the digestive stability of the red-pigmented lycopene and other carotenoids brought in nutritional quantity within different food matrixes, using the TNO gastrointestinal tract model (TIM). This multicompartmental dynamic system accurately reproduces the main parameters of gastric and small intestinal digestion in human. In vitro digestions of a standard meal containing red tomato (RT), yellow tomato (devoid of lycopene), or lycopene beadlets were performed. Zeaxanthin and lutein were stable throughout artificial digestions, whereas beta-carotene and all-trans lycopene were degraded (similar to 30 and 20% loss at the end of digestion, respectively) in the jejunal and ileal compartments. The recovery of beta-carotene in the digesta of the RT meal was significantly lower than that in the yellow one, showing a food matrix effect. In the same way, until 180 min of digestion, the recovery percentages of all-trans lycopene from RT were significantly lower than those issued from the supplement. Isomeric conformation also influenced the stability of carotenoids, 5-cis lycopene being the most stable isomer followed by all-trans and 9-cis. No trans-cis isomerization of lycopene occurred in the TIM. By using a relevant dynamic in vitro system, this study allowed us to gain further insight into the parameters influencing the digestive stability of carotenoids, and therefore their bioavailability, in humans.

Publication Inra prise en compte dans l'analyse bibliométrique des publications scientifiques mondiales sur les Fruits, les Légumes et la Pomme de terre. Période 2000-2012. http://prodinra.inra.fr/record/256699; International audience; BACKGROUND: Cohort studies suggested that individuals with higher intake of tomatoes and tomato products have a lower risk of degenerative diseases. Lycopene, an antioxidant and antiproliferative carotenoid, has been hypothesized to be responsible for the health benefits of tomatoes. However, studies demonstrated a higher potential of tomatoes compared to lycopene to reduce oxidative stress or carcinogenesis. AIM OF THE STUDY: Our study aimed at distinguishing lycopene effect from that of tomato on oxidative stress, by using yellow tomato, a tomato variety devoid of lycopene. METHODS: Effects of feeding with none (control), 16% freeze-dried yellow tomato (YT), 16% freeze-dried red tomato (RT) or 0.05% lycopene beadlets (LB) were compared in a rat model with mild oxidative stress induced by low vitamin E diet (LVED). Four groups of 10 rats were fed ad libitum for 6 weeks. Physiological parameters such as ingesta, body, spleen and liver weights, cholesterol and triglycerides (TG) levels were assessed. Lycopene and vitamin E concentrations and oxidative stress biomarkers were measured in the plasma and/or liver and/or heart tissue of the rats. RESULTS: RT, YT, and LB had no effect on rats' ingesta, body and spleen weights. RT, YT and LB had no effect on plasma cholesterol concentration. RT decreased TG level compared to control, YT and LB (P < 0.05). Rats fed RT or LB accumulated lycopene in plasma in contrast with rats fed YT. Heart level of thiobarbituric reactive species (TBARS) in rats fed RT or YT was lower than that in the control and the LB fed rats (P < 0.05). Despite similar concentrations of lycopene in plasma and liver, rats fed LB showed a significantly higher heart level of TBARS than rats fed tomatoes. RT increased erythrocyte superoxide dismutase (eSOD) activity compared with LB and nitric oxide (NO) level compared with control and LB. LB decreased ferric reducing ability of plasma (FRAP) level compared with control, RT and LB (P < 0.05). CONCLUSION: Our study showed for the first time that tomatoes, containing or not containing lycopene, have a higher potential than lycopene to attenuate and or to reverse oxidative stress-related parameters in a mild oxidative stress context.

The ZENITH Study is supported by the European Commission ‘Quality of Life and Management of Living Resources’ Fifth Framework Program, Contract No : QLK1-CT-2001-00168; International audience; BACKGROUND: Adjustments in intestinal absorption and losses of zinc (Zn) are thought to maintain Zn homeostasis when dietary intake levels are altered. Zn status may also influence efficiency of intestinal Zn absorption. OBJECTIVES: To determine the impact of dietary intake and status of some micronutrients on Zn absorption in late middle-aged men. DESIGN AND PARTICIPANTS: Dietary intake and status of Zn, Cu, Fe, vitamin A, C and fibre, and absorption of Zn were measured in 48 men, aged 58-68 y, confined to a metabolic unit and consuming a typical French diet. Dietary intake was estimated using 4-day food-intake records (including the weekend) and the GENI program. To assess Zn status, serum, erythrocyte, urine Zn levels and serum alkaline phosphatase activity were determined. Zn absorption was determined using the isotope double-labelling method. Zn stable isotopic ratios were measured in plasma samples collected before and 48 h after isotope administration using ICP/MS. RESULTS: Zn intake within the group of men varied from 5.7 to 20.5 mg/day and averaged 12.9 mg/day. Serum Zn level varied from 10 to 18 micromol/l and averaged 12.9 micromol/l. Zn absorption varied from 12 to 46% and averaged 29.7%. Zn absorption was not significantly (P > 0.05) correlated with Zn intake or with any of the Zn status parameters. Zn absorption was only slightly negatively correlated with serum and erythrocyte Zn levels and with serum Fe and ferritin levels in this study. CONCLUSION: Zn dietary intake and Zn absorption were satisfactory and led to an adequate Zn status in this population.

Background Prospective studies indicate that tomato consumers are protected against prostate cancer. Lycopene has been hypothesized to be responsible for tomato health benefits. Objective Our aim was to differentiate the effects of tomato matrix from those of lycopene by using lycopene-rich red tomatoes, lycopene-free yellow tomatoes, and purified lycopene. Design Thirty healthy men (aged 50-70 y old) were randomly assigned to 2 groups after a 2-wk washout period. In a crossover design, each group consumed yellow and red tomato paste (200 g/d, which provided 0 and 16 mg lycopene, respectively) as part of their regular diet for 1 wk separated by 2 wk of washout. Then, in a parallel design, the first group underwent supplementation with purified lycopene (16 mg/d) for 1 wk, whereas the second group received a placebo. Sera collected before and after the interventions were incubated with lymph node cancer prostate cells to measure the expression of 45 target genes. Results Circulating lycopene concentration increased only after consumption of red tomato paste and purified lycopene. Lipid profile, antioxidant status, prostate-specific antigen, and insulin-like growth factor I were not modified by consumption of tomato pastes and lycopene. We observed significant up-regulation of IGFBP-3 and Bax:Bcl-2 ratio and down-regulation of cyclin-D1, p53, and Nrf-2 after cell incubation with sera from men who consumed red tomato paste when compared with sera collected after the first washout period, with intermediate values for yellow tomato paste consumption. Cell incubation with sera from men who consumed purified lycopene led to significant up-regulation of IGFBP-3, c-fos, and uPAR compared with sera collected after placebo consumption. Conclusion Dietary lycopene can affect gene expression whether or not it is included in its food matrix. This trial was registered by the French Health Ministry at http://www.sante-sports.gouv.fr as 2006-A00396-45.

International audience; Low intracellular magnesium (Mg) contents may be observed in case of severe Mg insufficient intake or because of genetic regulation. This work was conducted to investigate the influence of intracellular Mg content on erythrocyte Mg(2+) influx and efflux in mice with low nutritionally and genetically (MGL and MGH mice) Mg status. C57BL6 mice were fed for 2 wks a diet containing 1000 mg Mg/kg diet Mg (control group), 100 mg Mg/kg diet (Mg-marginal group) or 30 mg Mg/kg diet (Mg deficient group), while mice with low (MGL) and high (MGH) Mg levels were fed a control diet for 2 wks. The quantification of erythrocyte Mg(2+) influx and efflux was performed using a stable isotope of Mg. Our results showed that erythrocyte Mg(2+) influx and efflux were respectively increased and decreased in nutritional Mg deficiency; while in genetically determined Mg status Mg(2+) fluxes were lower in MGL mice compared to MGH mice. Moreover Mg(2+) efflux was significantly correlated to Mg level in erythrocytes in all the mice studied (p < 0.001). In conclusion, erythrocyte Mg(2+) influx and efflux are modulated by low Mg status, namely decreased Mg(2+) efflux compensate for nutritional Mg deficiency, while the genetic regulation of erythrocyte Mg(2+) content depends on modification of Mg(2+) influx.

Background previous studies have shown that non-digestible inulin-type fructan intake can increase intestinal mineral absorption in both humans and animals. However, this stimulatory effect on intestinal absorption may depend on experimental conditions such as duration of fermentable fiber intake, mineral diet levels and animals' physiological status, in particular their age. Objectives the aim of this study was to determine the effect of inulin intake on Ca and Mg absorption in rats at different age stages. Methods eighty male Wistar rats of four different ages (2, 5, 10 and 20 months) were randomized into either a control group or a group receiving 3.75% inulin in their diet for 4 days and then 7.5% inulin for three weeks. The animals were fed fresh food and water ad libitum for the duration of the experiment. Intestinal absorption of Ca and Mg was determined by fecal monitoring using stable isotopic tracers. Ca and Mg status was also assessed. Results absorption of Ca and Mg was significantly lower in the aged rats (10 and 20 mo) than in the young and adult rat groups. As expected, inulin intake increased Ca and Mg absorption in all four rat groups. However, inulin had a numerically greater effect on Ca absorption in aged rats than in younger rats whereas its effect on Mg absorption remained similar across all four rat age groups. Conclusion the extent of the stimulatory effect of inulin on absorption of Ca may differ according to animal ages. Further studies are required to explore this effect over longer inulin intake periods, and to confirm these results in humans.

The ZENITH study is supported by the European Commission “Quality of Life and Management of Living Resources” Fifth Framework Program, Contract No : QLK1-CT-2001-00168; International audience; BACKGROUND: Zinc supplementation may be beneficial for health. Assessing exchangeable zinc pools may be a useful approach to evaluate zinc status. OBJECTIVE: We evaluated the effects of long-term supplementation with 2 moderate doses of zinc on the mass of exchangeable zinc pools. DESIGN: Three groups of healthy, late-middle-aged men (n = 16 per group) participated in a stable-isotope zinc kinetic study after 6 mo of daily supplementation with 0 (placebo), 15, or 30 mg Zn. At the end of the supplementation period, each subject received an intravenous injection of 0.89 mg (70)Zn, and the plasma zinc disappearance curve was monitored for the next 10 d. Two approaches were used to determine the characteristics of the exchangeable zinc pools: 1) formal 3-compartmental modeling and 2) a simplified determination of the total mass of the rapidly exchangeable zinc pool (EZP). RESULTS: In the placebo group, the exchangeable zinc pool masses for the 3 considered pools were as follows: 2.15, 12.7, and 100.5 mg Zn. The rapidly exchangeable zinc pool mass in the placebo group was 143 mg Zn. Zinc supplementation significantly increased the exchangeable zinc pool masses regardless of the approach used to determine these pools. In addition, these data confirm that exchangeable zinc pool masses correlate positively with total zinc intake and negatively with subject age and do not correlate with plasma zinc concentrations. CONCLUSION: Our data show that long-term supplementation with 2 moderate doses of zinc is an efficient way to increase exchangeable zinc pool masses in late-middle-aged men.