European Journal of Nutrition (v.49, #6)

Effects of Mediterranean diets with low and high proportions of phytate-rich foods on the urinary phytate excretion by Rafael M. Prieto; M. Fiol; J. Perello; R. Estruch; E. Ros; P. Sanchis; F. Grases (321-326).
Important health benefits have been reported recently to phytate intake. This includes the prevention of pathological calcifications such as renal calculi, dental calculi and cardiovascular calcification, due its action as crystallization inhibitor of calcium salts, and as preventive of cancer.The aim of this study was to establish a relation between the intake of phytate, through consumption of typical components of the Mediterranean diet (including nuts), and its excretion in urine.This study recruited participants from subjects included in a larger trial (PREDIMED) of food habits, that were assigned to one of two diet groups: (1) the Mediterranean diet with low proportion of phytate-rich food group, where participants were asked to maintain their usual diet; and (2) the Mediterranean diet with high proportion of phytate-rich food group, where participants were asked to increase phytate-rich foods in their diet. Phytate intake was assessed on the basis of a food frequency questionnaire. Urinary phytate excretion was determined in 2-h urine samples.The overall phytate consumption of the Mediterranean diet with high proportion of phytate-rich food group (672 ± 50 mg) was significantly higher than the Mediterranean diet with low proportion of phytate-rich food group (422 ± 34 mg), representing a 59% difference. Urinary phytate excretion was also significantly higher (54%) in the Mediterranean diet with high proportion of phytate-rich food group (1,016 ± 70 μg/L) than the Mediterranean diet with low proportion of phytate-rich food group (659 ± 45 μg/L).Mediterranean diets high in whole cereals, legumes and nuts compared to Mediterranean diets low in these phytate-rich foods increase the urinary phytate excretion in humans.
Keywords: Phytate; Food consumption; Urinary excretion

Competitive inhibition of carotenoid transport and tissue concentrations by high dose supplements of lutein, zeaxanthin and beta-carotene by Yingming Wang; D. Roger Illingworth; Sonja L. Connor; P. Barton Duell; William E. Connor (327-336).
Carotenoids may interact differently in their absorption and transport in animals and humans. The simultaneous administration of large amounts of lutein, zeaxanthin and beta carotene would affect not only plasma values but also their concentrations in the retina and other tissues.In this study, we investigated the transport, distribution and interactions of lutein, zeaxanthin and beta-carotene in the plasma, retina and other tissues of chicks fed supplements rich in lutein, zeaxanthin or beta-carotene.Newly hatched male Leghorn chicks were randomly assigned to ten groups. One group provided baseline data (1-day-old group). The other groups were fed one of the following six diets for 14 or 28 days: high lutein diet; high zeaxanthin diet; three high beta-carotene supplemented diets and the control diet. Plasma and tissues including retina were analyzed for lutein and zeaxanthin and beta-carotene at baseline and at 14 and 28 days.All tissues had increased concentrations of lutein after the high lutein diet and had increased concentrations of zeaxanthin after the high zeaxanthin diet. After 28 days, the retinal concentrations of lutein and zeaxanthin in the chicks supplemented with lutein (27.2 mg/kg diet) and zeaxanthin (15.3 mg/kg diet) increased 128 and 116%, respectively, compared to the retinas of chicks fed the control diet (lutein 5.2 mg/kg and zeaxanthin 1.7 mg/kg). Lutein was decreased in plasma and other non-retinal tissues when the diet was supplemented with zeaxanthin; likewise, zeaxanthin was decreased in plasma and non-retinal tissues after the lutein supplement. Zeaxanthin increased in the retina after the high lutein supplement, and retinal lutein was maintained after the high zeaxanthin supplement. The high beta-carotene supplement increased the beta-carotene content of plasma and liver very little, and beta-carotene was not found in any other tissue in the chick, including the retina. More importantly, beta-carotene decreased the concentrations of both lutein and zeaxanthin in the plasma and most tissues, including the retina.High dose dietary supplementation of a single carotenoid may alter the assimilation of other carotenoids. The retina appears to have the capacity to preserve accumulation of lutein and zeaxanthin, but this capacity is diminished when intake of beta-carotene is high.
Keywords: Supplements; Carotenoid absorption and interactions; Retinal carotenoids

Fructose and saturated fats predispose hyperinsulinemia in lean male rat offspring by C.-Y. Oliver Chen; Jimmy Crott; Zhenhua Liu; Donald E. Smith (337-343).
Early exposure to suboptimal nutrition during perinatal period imposes risk to metabolic disorders later in life. Fructose intake has been associated with increases in de novo lipogenesis, dyslipidemia, insulin resistance, and obesity. Excess consumption of saturated fat is associated with metabolic disorders.Objective of this animal study was to investigate morphological, metabolic, and endocrine phenotypes of male offspring born to dams consuming diets containing either 30% fructose, 9.9% coconut fat and 0.5% cholesterol (F + SFA) or 30% glucose, and 11% corn oil (C), 1 month before conception and during gestation and nursing.Proven male and female Sprague Dawley breeders were fed ad libitum with either F + SFA or C diet throughout the study. At weaning, five male pups from each group were sacrificed for determining morphological phenotypes. The other five male offspring from each group were rehabilitated to the C diet for an additional 12 weeks. At the age of 15 weeks, morphological phenotypes and blood biochemistries [glucose, insulin, growth hormone (GH), insulin-like growth factor-1 (IGF-1), corticosterone, and testosterone] of male adult offspring were then assessed.Body weight (BW) and body length of the F + SFA male adult offspring was slightly smaller than the C. The BW-adjusted epididymal and retroperitoneal fat depots of the F + SFA adult offspring were significantly 18 and 44% smaller than the C, respectively. GH and IGF-1 were not different in adult offspring between groups. Fasted plasma insulin of the F + SFA adult offspring was 64% larger than the C (P ≤ 0.0001) and homeostasis model assessment value was 55% larger (P = 0.004). There were negative correlations between fat depot sizes and plasma insulin in adult offspring.Our results suggest that, through fetal programming, an early exposure to both fructose and saturated fats may cause hyperinsulinemia and insulin insensitivity in the nonobese male rats later in life.
Keywords: Adiposity; Metabolic programming; Fructose; Insulin; Saturated fat

Bilberry juice modulates plasma concentration of NF-κB related inflammatory markers in subjects at increased risk of CVD by Anette Karlsen; Ingvild Paur; Siv K. Bøhn; Amrit K. Sakhi; Grethe I. Borge; Mauro Serafini; Iris Erlund; Petter Laake; Serena Tonstad; Rune Blomhoff (345-355).
Bilberries are abundant in polyphenols. Dietary polyphenols have been associated with strategies for prevention and treatment of chronic inflammatory diseases. We investigated the effect of bilberry juice on serum and plasma biomarkers of inflammation and antioxidant status in subjects with elevated levels of at least one risk factor for cardiovascular disease (CVD).In a randomized controlled trial, participants consumed either bilberry juice (n = 31) or water (n = 31) for 4 weeks.Supplementation with bilberry juice resulted in significant decreases in plasma concentrations of C-reactive protein (CRP), interleukin (IL)-6, IL-15, and monokine induced by INF-γ (MIG). Unexpectedly, an increase in the plasma concentration of tumor nuclear factor-α (TNF-α) was observed in the bilberry group. CRP, IL-6, IL15, MIG, and TNF-α are all target genes of nuclear factor- kappa B (NF-κB), —a transcription factor that is crucial in orchestrating inflammatory responses. Plasma quercetin and p-coumaric acid increased in the bilberry group, otherwise no differences were observed for clinical parameters, oxidative stress or antioxidant status. Furthermore, we studied the effect of polyphenols from bilberries on lipopolysaccharide (LPS)-induced NF-κB activation in a monocytic cell line. We observed that quercetin, epicatechin, and resveratrol inhibited NF-κB activation.These findings suggest that supplementation with bilberry polyphenols may modulate the inflammation processes. Further testing of bilberry supplementation as a potential strategy in prevention and treatment of chronic inflammatory diseases is warranted.
Keywords: Bilberry; NF-κB; Cytokines; Polyphenols; Human intervention; Cell culture

trans Fatty acid consumption, lifestyle and type 2 diabetes prevalence in a Spanish population by Kyriaki Papantoniou; Montserrat Fíto; Maria-Isabel Covas; Daniel Muñoz; Helmut Schröder (357-364).
To analyse the association of trans fatty acid (TFA) consumption with the risk of type 2 diabetes and lifestyle in a South European population.Data were obtained from two population-based cross-sectional surveys conducted in Gerona (Spain) in 2000 and 2005. The present analysis included 7,774 free-living Spanish men and women aged 35–74 years. Diet was assessed by a validated food frequency questionnaire. Fasting blood sugar was measured and history of diabetes recorded. trans Fatty acid intake was relatively low in our study population (1.5 g d−1 for women and 1.8 g d−1 for men). Multiple logistic regression analysis revealed a null association between TFA intake and risk of type 2 diabetes in men and women. Total energy intake, alcohol consumption and the prevalence of smoking increased across quartiles of TFA intake. An inverse association was found between TFA intake and the consumption of vegetables, fruit, fish, legumes, white bread and olive oil in both genders (p < 0.001) after adjusting for energy intake. In contrast, intakes of meat, sausages and pastry products increased across quartiles of TFA intake in both genders (p < 0.001). trans Fatty acid intake was not associated with a higher risk of type 2 diabetes. Higher TFA intake was associated with less healthy lifestyle and dietary habits in both sexes.
Keywords: trans Fatty acids; Type 2 diabetes; Lifestyle; Diet; Spanish population

Folates in bread: retention during bread-making and in vitro bioaccessibility by Veronica Öhrvik; Helena Öhrvik; Jonas Tallkvist; Cornelia Witthöft (365-372).
Bread is an important folate source in several countries. However, bread-making was reported to cause losses of endogenous bread folates (~40%) as well as added synthetic folic acid (~30%). Furthermore, the bread matrix is suggested to inhibit absorption of folates.To (1) estimate retention of both, endogenous folates and synthetic fortificants, during bread-making, (2) assess in vitro folate bioaccessibility from breads and a breakfast meal and (3) assess in vitro folate uptake.Retention of folate forms was assessed by preparing fortified (folic acid and [6S]-5-CH3-H4folate) wholemeal breads and collect samples from dough, proofed dough and the bread. In vitro folate bioaccessibility was assessed using the TNO gastrointestinal model TIM. In vitro folate uptake was assessed using a novel Caco-2 cell/stable isotope model. Folate content in samples was measured using LCMS.Bread-making resulted in losses of 41% for endogenous folates and up to 25 and 65% for folic acid and [6S]-5-CH3-H4folate fortificant, respectively. 75% of endogenous bread folates and 94% of breakfast folates were bioaccessible as assessed by TIM. From [6S]-5-CH3-H4folate-fortified bread, relative folate uptake into Caco-2 cells was 71 ± 11% (P < 0.05) when compared with a standard solution.Retention of folic acid fortificant during bread-making was substantially higher compared to retention of [6S]-5-CH3-H4folate fortificant. Data from the TIM and Caco-2 cell trials suggest an inhibiting effect of the tested bread matrices on in vitro bioaccessibility of folates, whereas folate bioaccessibility from a breakfast meal is almost complete.
Keywords: Folates; TNO gastrointestinal model TIM; Bread-making; In vitro bioaccessibility; Caco-2-cell/stable isotope model

Disease preventing effects gained by garlic consumption have been recognized since early period of history, making commercially available garlic supplements attractive to the general public. Possible pharmacokinetic interactions which could occur between applied drugs and aged garlic extract (AGE) are unknown.To test in vitro impact of some garlic phytochemicals on P-glycoprotein (Pgp), the most recognized efflux transporter, and the effect of AGE on passive membrane permeability, absorptive and secretory intestinal transporters.Rat small intestine and Caco-2 cell monolayers, mounted in side-by-side diffusion chambers were used.Hydrophilic sulphur compounds increased Pgp mediated Rhodamine 123 (Rho123) efflux, whereas the lipophilic ones increased Pgp efflux through rat ileum but not through Caco-2 cell monolayers. Increased activities of secretory (Pgp, multidrug-resistance associated protein 2) and absorptive (monocarboxylate transporter 1, organic anion transporting polypeptide) transporters involved in drug absorption were observed in rat small intestine and Caco-2 cell monolayers in the presence of AGE. Transport of drugs mediated by breast cancer resistance protein and H+-oligopeptide transporter 1 was activated in rat intestine but inhibited through Caco-2 cells. Passive membrane permeability of tested compounds remained unaltered through rat small intestine, while significant changes were observed with Caco-2 cell monolayers.Due to the observed in vitro pharmacokinetic interactions between AGE and investigated cardiovascular, antidiabetic and antiviral drugs, in vivo absorption changes are possible, but the magnitude of change depends on the most profound process involved (influx, efflux, passive diffusion) in compounds permeability.
Keywords: Aged garlic extract; Drugs; Interactions; Intestinal transporters; Rat intestine; Caco-2 cell monolayers