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Alternative or complementary treatments to a gluten-free diet are urgently needed for Celiac Dis-ease. By exploiting the health-promoting properties of polyphenols on a transgenic mouse model of Celiac Disease enteropathy, this study provides the first in vivo evidences regarding the ability of 1 mg.day-1 doses of green tea catechins and grape seed procyanidins to ameliorate some of the most characteristic histological changes of gliadin-treated DQ8 mice, including villus flattening, crypt hyperplasia, and infiltration of intraepithelial lymphocytes. Mechanistically, polyphenols were found to increase the intestinal nucleophilic tone of DQ8 mice by orchestrating an adaptive antioxidant response characterized by enhanced GSR enzyme activity and GSH content. Taken together, this work constitutes a highly relevant breakthrough as it provides the fundamental basis concerning the significance of natural polyphenols to be used in, for instance, the development of innovative functional foods aimed at CD individuals.

In the original published version of this article, an error was present in the author's name. The last name of "Delia Luongo" was incorrectly listed as "Lungo". The authors apologize for this mistake. Both the HTML and PDF versions of the article have been updated to correct the error. Abstract In the current era of high consumption and increasing waste, many products that are believed to be unusable can find a new purpose in the market. For example, the grape peel waste resulting from the production of wine contains numerous bioactive compounds. In reality, grape peels are by-products of winemaking that can be conveniently reused in many different ways, including agronomic use and cosmetic industry applications. Moreover, the by-products can also be used in the energy field as biomass for the production of biogas or in food plants for the production of energy. In this article, to extract polyphenols, grape peels were processed via a cyclically pressurized extraction method known as rapid solid-liquid dynamic extraction (RSLDE), which does not require the use of any organic solvent or include heating or cooling processes that can cause the loss of substances of interest. To better understand the cyclically pressurized extraction process, a numerical simulation was performed to evaluate the exchange between the grape piece solid matrix and water during the extraction process. Furthermore, a finite element model was used to numerically determine the time-dependent concentration distribution at specific times.

Oxidative stress is a key mediator of autoimmune/neurodegenerative disorders. The antioxidant/anti-inflammatory effect of a synthetic conjugated linoleic acid (CLA) mixture in MRL/MpJ-Faslpr mice (MRL/lpr), an animal model of neuropsychiatric lupus, was previously associated with the improvement of Nuclear factor-E2-related factor 2 (Nrf2) defences in the spleen and liver. However, little is known about the neuroprotective ability of CLA mixture. This study investigates the age-dependent progression of oxidative stress and the hyperactivation of redox-sensitive compensatory pathways (macroautophagy, Nrf2) in old/diseased MRL/lpr mice brains, and examines the effect produced by dietary CLA supplementation. Disrupted redox homeostasis was evidenced in the blood, liver and brain of 21- to 22-week old MRL/lpr mice (Old) compared to young animals (Y; 8- to 10-week old). This alteration was associated with significant hyperactivation of compensatory mechanisms (macroautophagy, Nrf2 and astrocyte activation) in the brains of Old mice. Five-week daily supplementation with CLA (650 mg/kg-1 body weight) of 16-week old mice (CLA+Old) diminished all the pathological hallmarks at a level comparable to Y mice or healthy controls (BALB/c). Such data demonstrated that MRL/lpr mice can serve as a valuable model for the evaluation of the effectiveness of neuroprotective drugs. Notably, the preventive effect provided by CLA supplementation against age-associated neuronal damage and hyperactivation of compensatory mechanisms suggests that the activation of an adaptive response is, at least in part, accountable for its neuroprotective ability.

Objective: Short chain fatty acids (SCFAs) derived from dietary fiber fermentation by gut microbiota have been identified as one of the mechanisms behind the association between habitual whole- grain intake and a lower risk of cardiometabolic diseases. The aims of the present work are: (1) to evaluate whether a whole-grain wheat-based diet may increase SCFAs concentration, and (2) to identify possible associations between SCFAs and metabolic changes observed after the nutritional intervention. Methods: Fifty-four subjects participated in the trial. They underwent a 12-wk dietary intervention based on whole-grain or refined cereal products. At baseline and after the intervention, glucose, insulin, triacylglycerol, inflammatory markers (hs-CRP, IL-1 ra, IL-6, and TNF-a), and SCFAs plasma concentrations were evaluated. Results: After the intervention, in the whole-grain group fasting plasma propionate concentrations were higher than at baseline, whereas a reduction was detected in the control group. The absolute changes (end of trial minus baseline) in fasting plasma propionate concentrations were signifi- cantly different between the two groups (P ¼ 0.048). The absolute changes of fasting propionate correlated with cereal fiber intake (r ¼ 0.358, P ¼ 0.023), but no significant correlations with clinical outcomes were found. However, postprandial insulin was significantly decreased in the group having the absolute changes of fasting propionate concentration above the median value (P ¼ 0.022 versus subjects with fasting propionate changes below the median value). Conclusions: A 12-wk whole-grain wheat-based diet increases fasting plasma propionate. This increase correlates with the cereal fiber intake and is associated with lower postprandial insulin concentrations.

Celiac Disease (CD) is characterized by activation of intestinal gliadin-specific CD4+ T cells with a Th1 phenotype that plays a major role in the induction of enteropathy (1). HLA-DQ8-transgenic mice (DQ8) have widely been used to dissect the mechanisms underlying CD pathogenesis. In this model, we analysed the residual toxicity and immune response of an enzymatically modified (transamidated) gliadin (spf).

Polychlorinated biphenyls (PCBs) are persistent organic pollutants (POPs) causing adverse effects on both humans and animals such as endocrine disruption, neurotoxicity and immunomodulation. Immune system is an important target organ for many environmental contaminants. Macrophages represent an important component of the immune system of humans and animals; in fact, they are responsible for triggering innate immune response and host defence. Although it is well known that different environmental pollutants may affect immune function, only few studies have been carried out to date about the effects of PCBs in macrophages; while, at our knowledge, no study investigated the effects of these contaminants on porcine macrophages. The aim of the current study was to evaluate the effects of three non dioxin like PCB congeners (PCB 138, PCB 153 and PCB 180) alone and differently combined, on porcine macrophages cell line (3D4/31). The results of the current study showed that ndl-PCBs reduced significantly cell viability only at the highest tested concentrations (50 µM); such effect was not linked to apoptosis induction or cell cycle arrest. The contemporary presence of more than one contaminant (differently combined) did not induce any enhancement of effects on 3D4/31 cell line. These data highlighted the need to continue the evaluation of toxic properties of ndl-PCBs, which represent less studied PBCs, in particular in term of risk assessment.

The mucosal lesion present in coeliac disease is an immune-mediated injury triggered by gliadin and restricted by a particular assortment of major histocompatibility complex genes. In view of this, an immunomodulatory approach that induces tolerance to this antigen appears to be a possible alternative to a strict gluten-free diet in treating coeliac disease. We have shown that intranasal administration of multiple doses of whole gliadin is required to specifically inhibit T helper 1-like T-cell reactivity in BALB/c mice immunized parenterally with whole gliadin. However, T-cell activation to multiple antigens, as a consequence of the chemical complexity shown by the antigen gliadin, could hamper efforts to identify single component(s) useful for tolerance induction. In this study, gliadin fractions were purified and administered intranasally to study their ability to induce tolerance to whole gliadin in our animal model. We found that the alpha fraction was particularly effective in downregulating both the in vitro gliadin-specific T-cell proliferation and interferon-gamma production to whole gliadin. In particular, a purified alpha-gliadin was able to suppress the immune response to the entire gliadin mixture. These results demonstrate how an immune response to a complex antigen may be controlled by treatment with a purified component and specifically indicate alpha-gliadin to be a good candidate for further identification of short peptides to be used as tolerogens in this model.

In a search for bacteria having putative probiotic activity, we screened a collection of food-isolated microorganisms for the ability to survive at low pH in the presence of bile salts and for the production of antimicrobial compounds active against a number of animal pathogens. Among these, we found a strain that we classified as a member of Lactobacillus fermentum sp., and we further investigated its features. This organism was able to adhere to human enterocyte-like (Caco-2) cells with high efficiency as compared to that of a well known indicator strain. Chromatographic analysis indicated that at least two small (less than 3 kDa) factors were involved in mediating the in vitro interaction of L. fermentum with Caco-2 cells. Adhesion activity could be abolished by mild treatment of the bacterial cells in buffer and rescued by incubating them with either the same buffer after its use in the treatment or with chromatographic fractions containing each of the two factors, which indicated that these factors were loosely associated with the cell wall and that each of them was sufficient to warrant the adhesiveness of L. fermentum to Caco-2 cells. These data are suggestive of a novel mechanism of bacterial adhesion to epithelial cells.

The mucosal lesion in coeliac disease (CD) is an immune-mediated injury triggered by gliadin and associated with HLA-DQ2 and HLA-DQ8. In view of this, an approach that re-induces tolerance to this antigen should be considered as possible alternative to a strict gluten-free diet in treating CD. However, T-cell activation to multiple antigens, as a consequence of the chemical complexity shown by the antigen gliadin, could hamper the efforts to identify single component(s) useful for tolerance induction. To address this issue, a recombinant alpha-gliadin was tested in tolerance experiments in HLA-DQ8 transgenic mice. As tissue transglutaminase (tTG) treatment of gliadin, previously reported to enhance its stimulatory activity in CD, did not increase its immunogenicity when parenterally administered in these mice, untreated gliadin was used as immunogen. A decrease in systemic T cell responses to the recombinant alpha-gliadin was found after nasal administration of antigen, reflected by lymphocytes proliferation assay. Interestingly, while the immunisation protocol induced transcription of both Th1 (IFN-gamma) and Th2 (IL-4 and IL-10) cytokines, the tolerisation protocol down-regulated significantly only the IFN-gamma mRNA expression. More important, the recombinant alpha-gliadin induced a similar down-regulatory effect in mice immunised with a commercial preparation of wheat gliadin, that is a mixture of many different gliadin components. As the Th1 phenotype and the HLA-DQ8 molecule play a role in the pathogenesis of CD, our data underlined the potential usefulness of this recombinant protein for the immunomodulation of this disease.

The role and regulation of signal transduction pathways in proliferation and differentiation of intestinal epithelial cells are still poorly understood. However, growing evidences have been recently accumulated demonstrating that mitogen-activated protein kinases (MAPKs) play a pivotal function in the normal development of intestine. We have investigated, in the intestinal cell line HT-29, the regulation (namely activity and phosphorylation degree) of MAP kinases ERK 1 (p44) and ERK 2 (p42) during differentiation. Addition of fetal calf serum to HT-29 undifferentiated resting cells caused a rapid phosphorylation of both ERKs and an increase of their specific kinase activity. Moreover, nuclear translocation of ERK 1 and ERK 2 occurred concurrently to their activation, leading to the conclusion that ERK 1 and ERK 2 are classically regulated when quiescent HT-29 cells are induced to proliferate. Butyrate addition to the intestinal cell line resulted in terminal differentiation and in a selective down-regulation of ERK 2 activity (and phosphorylation degree) without any effect on ERK 1. Conversely, when HT-29 cells were differentiated by repeated passages in a glucose-free medium, we observed a progressive dephosphorylation and inactivation of p42 and p44 kinases along with the failure of serum to activate both the enzymes. Our findings suggest that, during the differentiation of intestinal cells, remarkable changes occur in ERK 1 and ERK 2 control mechanisms leading to an unresponsiveness of MAP kinase pathway.

The gut-associated lymphoid tissue is deputed both to protect from infectious diseases and to evoke immune tolerance. Efficient responses need mucosal adjuvants: starting from cholera toxin, new variants of cholera toxin were developed depleted of toxicity. In addition, lipid colloidal particles, bacterial DNA, and probiotics have been experimented. Tolerance is currently induced by means of the B subunit of cholera toxin, whereas new strategies encompass the use of probiotics, expansion of regulatory T cells and blocking of paracellular entry of antigens. Finally, we report different approaches developed for celiac disease, an immune-mediated disease whose triggering antigen is known.

The in vitro effects of four Fusarium toxins, fumonisin B(1) (FB(1)), alpha-zearalenol (alpha-ZEA), nivalenol (NIV) and deoxynivalenol (DON), on mitogen-induced cell proliferation were determined in swine whole-blood cultures. Considering the lack of sufficient toxicological data both on single and in combination effects, in vitro studies may contribute to risk assessment of these toxins. Incubation with increasing concentrations of FB(1) did not produce any consequence on proliferation; in contrast alpha-ZEA, NIV and DON showed an inhibitory effect. Dose-response curves for each mycotoxin were generated. NIV was found to be the most potent toxin followed by DON and alpha-ZEA. The effects of both FB(1)+alpha-ZEA and NIV+DON mixtures were also analysed to investigate possible interactions. The results indicated that combination of FB(1)+alpha-ZEA produces a synergistic inhibition of porcine cell proliferation; whereas there is no interaction between DON and NIV on porcine whole-blood proliferation, at tested concentrations.

Introduction: Celiac disease (CD), is the most common food-sensitive enteropathy in humans, caused by the lack of oral tolerance to wheat gluten (1). To study this disease we use a transgenic mouse model expressing the HLA-DQ8 molecule in the absence of endogenous class II genes (2). The adjuvant function Lactobacillus casei is well known (3). In this study we analyzed the effects of oral administration of L. casei in DQ8 transgenic mice following mucosal sensitization with gliadin along with cholera toxin. Methods: DQ8 transgenic mice were administered intragastrically with 500 mg of a chymotryptic digest of gliadin (ct-gliadin) along with 25 ?g of cholera toxin (CT) on days 0, 7 and 14. In someexperiments L. casei (1x1010/dose, four doses/week) was co-administered per os. On day 21 mice were sacrificed. Spleen and MLN were isolated for in vitro assessment of gliadin-specific immunity. Small intestine fragments were collected for RNA analysis and immunomorphometric measurements. Results: Co-administration of L.casei in gliadin-sensitive DQ8 transgenic mice caused a strong increase of the intestinal gliadin-specific cell mediated immune response (SI: 2.75 ± 0.1 vs 4.4 ± 0.03; control vs L. casei; p

Conjugated linoleic acid (CLA), a naturally occurring peroxisome proliferator-activated receptor gamma (PPAR gamma) ligand, exhibits proapoptotic, immunomodulatory, and anticancer properties. In this study, we examined the biological effects of CLA administration in the MRL/MpJ-Fas(lpr) mouse, an animal model of systemic lupus erythematosus (SLE). We found that CLA exerted apparently opposed activities in in vitro experiments, depending on its concentration: 100 microM CLA downregulated IFN gamma synthesis and cell proliferation of splenocytes, in association with apoptosis induction and a decrease of intracellular thiols (GSH + GSSG), whereas 25 microM CLA did not significantly influence cell proliferation but enhanced the expression of gamma-glutamylcysteine ligase catalytic subunit (GCLC) and intracellular GSH concentration. Interestingly, the antiproliferative effect at 100 microM was not inhibited by the PPAR gamma antagonist GW9662. In vivo, CLA administration drastically reduced SLE signs (splenomegaly, autoantibodies, and cytokine synthesis), a condition paralleled by the enhancement of GCLC expression and intracellular GSH content. Moreover, CLA administration significantly downregulated nuclear factor kappaB activity independent of PPAR gamma activation and apoptosis induction. In conclusion, enhanced GSH content and GCLC expression in CLA-treated mice suggest a novel biochemical mechanism underlying its immunomodulatory activity and the beneficial effects on murine SLE signs.