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Background and Aims: Stress is hypothesized to facilitate the development of obesity, whose the foundations are already set during childhood and adolescence. We investigated the relationship between the stress-system, selected mechanisms of energy homeostasis and insulin resistance (IR) in a sample of European adolescents., Methods and Results: Within HELENA-CSS, 723 adolescents (12.5-17.5 years) from 10 European cities provided all the necessary data for this study. Fasting blood samples were collected for cortisol, leptin, insulin and glucose analysis. HOMA-IR was calculated from insulin and glucose concentrations. Adolescents' body fat (BF) %, age and duration of exclusive breastfeeding were assessed. For boys and girls separately, the relationship of cortisol with leptin, insulin, glucose and HOMA-IR was examined by computing Pearson correlation coefficients and Hierarchical Linear Models (HLMs), with 'city' as cluster unit, adjusting for age, BF% and duration of exclusive breastfeeding. In boys, Pearson correlation coefficients illustrated positive correlations of cortisol with insulin (r = 0.144; p = 0.013), glucose (r = 0.315; p < 0.001) and HOMA-IR (r = 0.180; p = 0.002), whilst in girls, this positive relationship was observed for leptin (r = 0.147; p = 0.002), insulin (r = 0.095; p = 0.050) and HOMA-IR (r = 0.099; p = 0.041), but not for glucose (r = 0.054; p = 0.265). Observed associations were independent of adolescents' age, BF% and duration of exclusive breastfeeding after computing HLMs., Conclusion: This study suggests that the stress-system is positively related to mechanisms of energy homeostasis and IR in European adolescents, and reveals a potential small gender difference in this relationship. The hypothesis that stress might facilitate the development of obesity during adolescence is supported., (Copyright © 2014 Elsevier B.V. All rights reserved.)

The association between in vitro antioxidant capacity of dark chocolates with different cocoa percentage and the in vivo response on antioxidant status was investigated. In a randomized crossover design, 15 healthy volunteer consumed 100g of high antioxidants dark chocolate (HADC) or dark chocolate (DC). In vitro, HADC displayed a higher Total Antioxidant Capacity (TAC) than DC. In vivo, plasma TAC significantly peaked 2h after ingestion of both chocolates. TAC levels went back to zero 5h after DC ingestion whilst levels remained significantly higher for HADC. HADC induced a significantly higher urinary TAC in the 5-12h interval time than DC. No change was detected in urinary excretion of F2-isoprostanes. Plasma thiols and triacylglycerol (TG) levels significantly increased for both chocolate with a peak at 2h remaining significantly higher for DC after 5h respect to HADC. Results provide evidence of a direct association between antioxidant content of chocolate and the extent of in vivo response on plasma antioxidant capacity., (Copyright © 2011 Elsevier Ltd. All rights reserved.)

We propose a new data analysis approach for reactive oxygen species detection using Dihydrorhodamine 123 in blood monocytes and neutrophils. This approach, based on data transformation using lymphocytes as internal standard, allows to appreciate free radical production by monocytes also without Phorbol 12-myristate 13-acetate (PMA) activation. In addition, this method is sensitive to differences in healthy subjects due to sub-pathological conditions, such as hypercholesterolemia., (Copyright © 2012 Elsevier B.V. All rights reserved.)

Aim: The aim of the study was to assess food consumption in a group of Roman adolescents in order to compare the energy and nutrient intakes with requirements., Methods: The authors have carried out a food survey on the whole scholastic population of two schools of Rome from 2003 to 2005. Nutritional status of students was assessed by measuring height, weight according to international indications. Food consumption was assessed by food records., Results: Seventy hundred and seventy three subjects (773) 52% males, with an average age of 12.3 + or - 0.9 years were surveyed. The average daily intakes of fruit (128 g), vegetables (161 g), and legumes (12 g) were lower than recommended. The percentage of energy intake from fat (39%) and that from saturated fats (12%) were high. On the other hand, the percentage of energy intake from carbohydrates was low (46%) even if that from saturated fats (12%) was rather high. The students' diet was characterized by low intakes of fibre (16 g), calcium (815 mg) and iron (12 mg) in both males and females., Conclusion: Results indicate that the diet of these students is unbalanced in terms of macronutrients and deficient for some micro-nutrients, suggesting the need for nutrition education policy.

Crohn's disease and ulcerative colitis are two forms of inflammatory bowel disease (IBD). Genetic and environmental factors influencing the onset and course of this disease have recently been identified. Among the environmental and dietary factors involved in the development of inflammatory colon diseases, dietary polyphenols have been proposed as protective agents in distinct models of colon inflammation. However, despite the huge number of studies on the beneficial effects of polyphenols on health, their dietary effectiveness is unclear. In this review, we examine some of the evidence linking dietary polyphenol intake with protection against IBD., (Copyright 2009 Elsevier España, S.L. All rights reserved.)

Probiotic bacteria are normal inhabitants of microflora and may confer several benefits, including prevention against intestinal inflammation. However, the exact mode of action of probiotics is still largely unknown. The first line of defense against the entry of pathogens is represented by the gut membrane barrier and probiotics may prevent pathogen-induced membrane damage by inhibiting pathogen adhesion and maintaining the correct organization of the tight junction and cytoskeleton proteins. The gut immune system should not only protect the mucosa against pathogens, but also avoid hypersensitivity reactions to food proteins and normal microflora. Failure of induction or maintenance of oral tolerance has been postulated to be a cause of food allergy. Feeding probiotic bacteria may prevent or ameliorate the onset of allergic disease and the associated inflammatory reactions through mechanisms involving modulation of T regulatory cells. Breakdown in tolerance toward intestinal bacteria is a primary cause of inflammatory bowel disease. Recent studies have shown that probiotics may ameliorate experimental colitis in mice by inducing interleukin 10 and interleukin 10-dependent T regulatory cells. In this article, an update of the anti-inflammatory activity of different probiotics and of the more accredited mechanisms underlying such activities are reported.

Ceruloplasmin, a blue copper oxidase circulating in serum of all vertebrates, is a glycoprotein synthesized mainly in hepatocytes and secreted into plasma with six tightly bound atoms of copper per molecule. Many aspects of the mechanisms by which synthesis and secretion of this protein are regulated by copper are still not known. In HepG2 hepatocarcinoma cells this fine regulation is not maintained; we have then utilized Met-murine-hepatocytes (MMH), isolated from the liver of transgenic mice expressing a truncated form of c-Met (hepatocyte growth factor receptor), that are immortalized but not transformed. Copper deficiency was induced by treatment of cells with bathocuproine disulphonate. Experiments of metabolic labeling with 35S-methionine-cysteine and of Western blotting followed by immunostaining, demonstrated that maturation and secretion of ceruloplasmin but not its synthesis are affected by copper availability. In this paper we have shown that in copper deficiency ceruloplasmin accumulates in a pre-Golgi compartment, in which the protein is still in a Endo H sensitive form, and where presumably copper binding to the apo-protein takes place. Moreover, we found that treatment of copper-deficient cells with the proteasomal inhibitor lactacycstin leads to immature ceruloplasmin accumulation in the cell. We have optimized conditions to induce in vitro copper deficiency and found that MMH-D3 cells represent a suitable model to study in detail the molecular mechanism of copper-regulated ceruloplasmin synthesis, secretion and degradation.

The human intestinal Caco-2 cell line has been extensively used over the last twenty years as a model of the intestinal barrier. The parental cell line, originally obtained from a human colon adenocarcinoma, undergoes in culture a process of spontaneous differentiation that leads to the formation of a monolayer of cells, expressing several morphological and functional characteristics of the mature enterocyte. Culture-related conditions were shown to influence the expression of these characteristics, in part due to the intrinsic heterogeneity of the parental cell line, leading to selection of sub-populations of cells becoming prominent in the culture. In addition, several clonal cell lines have been isolated from the parental line, exhibiting in general a more homogeneous expression of differentiation traits, while not always expressing all characteristics of the parental line. Culture-related conditions, as well as the different Caco-2 cell lines utilized in different laboratories, often make it extremely difficult to compare results in the literature. This review is aimed at summarizing recent, or previously unreviewed, data from the literature on the effects of culture-related factors and the influence of line sub-types (parental vs. different clonal lines) on the expression of differentiation traits important for the use of Caco-2 cells as a model of the absorptive and defensive properties of the intestinal mucosa. Since the use of Caco-2 cells has grown exponentially in recent years, it is particularly important to highlight these methodological aspects in order to promote the standardization and optimisation of this intestinal model.

There is some evidence that zinc oxide (ZnO) protects against intestinal diseases. However, despite the suggestions that ZnO may have an antibacterial effect, the mechanisms of this protective effect have not yet been elucidated. We investigated the potential benefits of ZnO in protecting intestinal cells from damage induced by enterotoxigenic Escherichia coli (ETEC, strain K88) and the related mechanisms, using human Caco-2 enterocytes. Cell permeability, measured as transepithelial electrical resistance (TEER), was unaffected by 0.01 and 1 mmol/L ZnO treatments and moderately increased by 5 mmol/L ZnO, compared with untreated cells. Transfer of (14)C-inulin was slightly increased by 5 mmol/L ZnO compared with untreated cells; transfer was unaffected by lower concentrations. The TEER and (14)C-inulin transfer were lower in ETEC-infected cells than in uninfected cells. Treatment of ETEC exposure with 0.2 mmol/L ZnO prevented disruption of membrane integrity. The ETEC was able to adhere to enterocytes and, to some extent, invade the cells. The ZnO treatment reduced bacterial adhesion and blocked bacterial invasion. The ETEC infection upregulated the expression of the inflammatory cytokines interleukin-8, growth-related oncogene-alpha and tumor necrosis factor-alpha, and reduced that of the anti-inflammatory cytokine transforming growth factor-beta, compared with uninfected cells. The addition of 0.2 or 1 mmol/L ZnO counteracted the alteration of cytokine mRNA levels caused by ETEC. The protective effects of ZnO were not due to any antibacterial activity, because the viability of ETEC grown in a medium containing ZnO was unaffected. In conclusion, ZnO may protect intestinal cells from ETEC infection by inhibiting the adhesion and internalization of bacteria, preventing the increase of tight junction permeability and modulating cytokine gene expression.

Retinol-binding protein (RBP) is the specific plasma carrier of retinol, encharged of the vitamin transport from the liver to target cells. Ligand binding influences the RBP affinity for transthyretin (TTR), a homotetrameric protein involved in the RBP/TTR circulating complex, and the secretion rate of RBP. In fact, in vitamin A deficiency, the RBP release from the hepatocytes dramatically decreases and the protein accumulates in the cells, until retinol is available again. The mechanism is still not clear and new cellular models are needed to understand in detail how the soluble RBP can be retained inside the cell. In fish, a vitamin A transport system similar to that of higher vertebrates is emerging, although with significant differences.

The present study investigated whether storage under modified-atmosphere packaging (MAP) affected the antioxidant properties of fresh lettuce (Lactuca sativa). Eleven healthy volunteers (six men, five women) consumed 250 g fresh lettuce, and blood was sampled before (0 h) and 2, 3 and 6 h after consumption. The protocol was repeated 3 d later with the same lettuce stored at 5 degrees C under MAP conditions (O2-N2 (5:95, v/v)). Results showed that after ingestion of fresh lettuce, plasma total radical-trapping antioxidant potential (TRAP), measured as area under the curve, was significantly higher (1.3 (sem 0.3) mmol/l per 6 h; P<0.05) than the value obtained with MAP-stored lettuce (0.1 (sem 0.2) mmol/l per 6 h). Plasma TRAP, quercetin and p-coumaric acid were significantly different from baseline values (P

Background & Aims: Dietary antioxidants, with additive and synergistic effects, can mediate the observed inverse association between plant food intake and risk of gastric cancer. We investigated whether the total dietary antioxidant potential of fruit and vegetables is an appropriate means of estimating the antioxidant impact on gastric cancer risk in a large population-based study., Methods: With a population-based case-control design, data were collected through face-to-face interviews with 505 newly diagnosed gastric adenocarcinoma patients and 1116 control subjects to assess dietary habits 20 years before interview. The total radical-trapping antioxidant potential (TRAP) of different plant foods was used to convert food frequency intake into antioxidant potential. Gastric cancer risk in groups exposed to higher levels of oxidative stress (smoking and Helicobacter pylori infection) was also examined., Results: Intake of antioxidant equivalents was inversely associated with the risk of both cardia and distal gastric cancer (odds ratio [OR], 0.65; 95% confidence interval [CI], 0.48-0.89 for the highest quartile of TRAP). Controlling for smoking, the inverse relationship between TRAP values displayed a clearer dose-response pattern. Never-smokers with the highest antioxidant intake had the lowest risk of cancer, 0.44 (95% CI, 0.27-0.71). Among H. pylori-infected subjects, the ORs varied between 0.66 and 0.41 for increasing levels of antioxidant potential., Conclusions: Our results suggest that dietary intake of antioxidants measured as total antioxidant potential is inversely associated with risk of both cardia and distal cancer. The innovative approach used in this study provides a new tool for investigating the relationship between dietary antioxidants and oxidative stress-related carcinogenesis.

Objectives: The present study was aimed at surveying the Italian food consumption patterns in the 90s. It represented the second nationwide food intake survey that was carried out by the Istituto Nazionale di Ricerca per gli Alimenti e la Nutrizione (INRAN)., Design: Cross-sectional study., Setting: Free-living households., Subjects: Sampled subjects: 1147 households randomly selected to be representative of the four main geographical areas (North-West, North-East, Centre, South). Analysed subjects: 1978 individuals out of 2734 initially collected in 15 Collaborative Centres strategically scattered through the national territory., Methods: A mixed 7-day based survey technique was applied in order to survey both individual and household consumption. At individual level, food intake was recorded by a self-compiled diary. At household level food data collection was by compilation of a food inventory by the dietician, a purchased/wasted foods diary and a recipes form both compiled by the person responsible for food related activities (decision of purchase, purchase, preparation of meals) in the household. All recorded data were monitored by the dieticians who visited the households participating in the study, at least three times. Household members were interviewed in order to collect socio-demographic, lifestyle and motivational information. Furthermore, field-workers performed the food coding and the input of data by an ad hoc developed software. The survey design allowed an internal quantitative check of food data. Several check steps were centrally performed, Results: The complex methodology caused the 46.8% response rate and afterwards a reduction of the analysed units (72% of the surveyed individuals). However, the analysed sample provided sufficiently reliable data for outlining the most relevant aspects of dietary patterns in Italy. In order to better interpret the results, controversial aspects are also illustrated and discussed in the text. The disparity analysis found that traditional diversities among Italian regions are still alive. In general, males eat more than females. Analysis according to the age class (children: 1-9 years old; adolescents: 10-17; adults: 18-64; elderly: >64) showed differences especially between the group of children vs all the others, but also in the two groups of young individuals vs adults and the elderly, that could represent clues of an incorrect way of eating., Conclusions: Taking into account the different methodology, the comparison with previous results showed changes in the Italian average diet complying with an increasing attention to healthy aspects by large sectors of the population, but also opposite tendencies that should be carefully monitored., Sponsorship: Minister delle Politiche Agricole e Forestali (Mi.P.A.F.).