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Immuno-laser capture microdissection (Immuno-LCM) has been used to analyze cell-specific gene expression profiles. However, the usefulness of such a technique is frequently limited by RNA degradation. We, therefore, developed a rapid protocol of LCM on mirror sections, which allows for preserving RNA integrity. With such a procedure, we investigated cell-type-specific gene expression of γδ intraepithelial lymphocytes (IELs) in untreated celiac disease (CD). An increase in TGF-β mRNA expression levels was observed in γδ + IELs compared to intestinal enterocytes (IEs), whereas anti-inflammatory IL-10 mRNA production from γδ + IELs was lower compared to IEs. In untreated CD patients, the production of anti-inflammatory cytokines by γδ + IELs is suggestive of a regulatory function, thus playing a critical role in limiting inflammation. This work underscores the importance of LCM on mirror sections as a valuable tool to perform cell-type-specific molecular analysis in tissue.

miRNAs are small noncoding RNAs that control gene expression at the posttranscriptional level. It has been recognised that miRNA dysregulation reflects the state and function of cells and tissues, contributing to their dysfunction. The identification of hundreds of extracellular miRNAs in biological fluids has underscored their potential in the field of biomarker research. In addition, the therapeutic potential of miRNAs is receiving increasing attention in numerous conditions. On the other hand, many operative problems including stability, delivery systems, and bioavailability, still need to be solved. In this dynamic field, biopharmaceutical companies are increasingly engaged, and ongoing clinical trials point to anti-miR and miR-mimic molecules as an innovative class of molecules for upcoming therapeutic applications. This article aims to provide a comprehensive overview of current knowledge on several pending issues and new opportunities offered by miRNAs in the treatment of diseases and as early diagnostic tools in next-generation medicine.

What is the central question of this study? Are differential patterns of circulating miRNAs associated with sleep duration in normal-weight European children and adolescents? What is the main finding and its importance? Differences in the expression level of circulating miR-26b-3p and miR-485-5p are positively associated with total sleep duration in healthy normal-weight children and adolescents.It is commonly recognized that sleep is essential for children's health, and that insufficient sleep duration is associated with negative health outcomes. In humans, sleep duration and quality are influenced by genetic, environmental and social factors. Epigenetic mechanisms, likewise, regulate circadian rhythms and sleep patterns. In the present study, we aimed to identify circulating microRNAs associated with sleep duration in a subsample of normal-weight European children/adolescents (n = 111) participating in the I.Family Study. Subjects were divided into two groups based upon self-reported sleep duration, according to the recommended amount of sleep for paediatric populations. Sleep needs for children 13 years were at least 9 h per day, and for children 13 were at least 8 h per day. There were group differences (short sleepers versus normal sleepers) in circulating levels of miR-26b-3p (mean (95% CI) = 2.0 (1.3-2.7) versus 2.3 (1.9-2.7), P = 0.05) and miR-485-5p (mean (95% CI) = 0.6 (0.3-0.9) versus 0.9 (0.7 - 1.0), P 0.001), adjusting for country of origin, age, sex, pubertal status, screen time and highest educational level of parents. Our findings show for the first time that sleep duration reflects the profile of specific circulating microRNAs in school-aged children and adolescents. It is conceivable that epigenetic modifications, mainly related to circadian rhythm control, may be modulated or interfere with sleep duration.

Scope Several studies reported a role of amylase/trypsin-inhibitors (ATIs) of common wheat species in promoting immune reactions. Here, we investigated in celiac disease (CD), the immunogenic properties of ATIs from diploid compared to common hexaploid wheats after an in vitro proteolytic hydrolysis. Methods and Results ATIs purified from two lines of diploid Triticum monococcum (TM), Monlis and Norberto-ID331, and from Triticum aestivum (TA), Sagittario, were digested with pepsin-chymotrypsin (PC) enzymes and analyzed using a proteomic approach, and subsequently their immune stimulatory properties were investigated on jejunal biopsies and T-cell lines from CD patients. No significant expression of IL-8 and TNF-α were detected on biopsies cultured with ATIs from TM in comparison with ATIs from TA. No significant IFN-γ production was observed in intestinal gliadin- raised T-cells in response to ATIs from both TM and TA wheats. Proteomic results revealed that both TM ATIs showed reduced stability to proteolytic enzymes compared to TA ones. Conclusion TM ATIs are substantially different from those of TA, showing a reduced ability to trigger the innate immunity in CD and a higher susceptibility to enzymatic hydrolysis.

Laser capture microdissection (LCM) is a powerful tool for selection and isolation of single cells or compartments from complex primary tissues to perform molecular analyses. Celiac disease is a genetic autoimmune disorder where the ingestion of gluten leads to damage in the small intestine. Increased intraepithelial lymphocytes and the presence of the lamina propria inflammatory infiltrate of the duodenal mucosa is a common part of the disease. These cells promote inflammatory processes through the release of cytokines. Here, we describe the use of LCM and real-time quantitative PCR (RT-qPCR) to analyze cytokine profile information in distinct duodenal mucosa tissue compartments of celiac patients.

Titanium dioxide (TiO2) is enclosed in many consumer products including pharmaceuticals, cosmetics, and foods. TiO2 (E171) is daily ingested as mixed nano- and submicron-sized particles since it is approved as a white colorant in Europe in a wide variety of food products, Noteworthy, the relevant risk assessment has never been satisfactorily concluded and growing alarms for human hazards deriving from TiO2 exposure are incrementally reported. The objective of the present study was to establish conceivable mechanisms by which nano-sized TiO2 particles affect physiological function of the intestinal epithelium layer. The well-established Caco-2 cell line differentiated for 21 days on permeable supports was used as a predictive model of the human intestinal mucosa to identify the biological response triggered by TiO2 particles. Exposure to 42 μg/mL TiO2 nanoparticles disrupted the tight junctions-permeability barrier with a prompt effect detectable after 4 h incubation time and wide effects on barrier integrity at 24 h. Transport and ultrastructural localization of TiO2 nanoparticles were determined by ICP-OES, TEM and ESI/EELS analysis, respectively. Nano-sized particles were efficiently internalized and preferentially entrapped by Caco-2 monolayers. Storage of TiO2 nanoparticles inside the cells affected enterocytes viability and triggered the production of pro-inflammatory cytokines, including TNF-α and IL-8. Taken together these data indicate that nano-sized TiO2 particles exert detrimental effects on the intestinal epithelium layer.

Laser capture microdissection (LCM) is a powerful tool for selection and isolation of single cells or compartments from complex primary tissues to perform molecular analyses. Celiac disease is a genetic autoimmune disorder where the ingestion of gluten leads to damage in the small intestine. Increased intraepithelial lymphocytes and the presence of the lamina propria inflammatory infiltrate of the duodenal mucosa is a common part of the disease. These cells promote inflammatory processes through the release of cytokines. Here, we describe the use of LCM and real-time quantitative PCR (RT-qPCR) to analyze cytokine profile information in distinct duodenal mucosa tissue compartments of celiac patients.

Enzymatic dough improvers (DIs) are increasingly used as baking co-adjuvants. Herein, an array of techniques, including Western blotting, PCR, electrophoresis-based and shotgun proteomics, was addressed to identify the enzymes in six commercial DI preparations. In particular, this work sought to exclude the possible undeclared use of amylolytic enzymes from porcine (or other animal origin) pancreas in DIs. PCR-amplified mitochondrial cytochrome b (mt cyt b) gene region and porcine pancreatic α-amylase were the targets of DNA-based and protein methods, respectively, both assuring a limit of detection lower than 0.5-0.1% (w/w). Aspergillum oryzae α-amylase and Hordeum vulgare (barley) β-amylase were the most represented enzymes in all DI samples. Although one sample was PCR-positive, none among the DIs contained porcine pancreatic enzymes. Comparative gas chromatographic analysis of fatty acids suggested that the porcine contamination might arise from hard fats of porcine origin (lard), emphasizing the need of performing analyses at the protein level when the targets are enzymes or proteins.

Background and aims Laser capture microdissection (LCM) is a powerful tool for the isolation of specific tissue compartments. We aimed to investigate the mucosal immune response that takes place in different intestinal compartments of IBD patients, dissected by LCM, analyzing cytokines expression profile and endoplasmic reticulum (ER) stress markers. Methods Frozen sections of gut were obtained from patients with Crohn’s disease (CD), ulcerative colitis (UC) and from controls. Using LCM, surface epithelium (SE) and lamina propria (LP) compartments were isolated and total RNA extracted. The relative expression of Th1, Th17 and Treg cytokines was evaluated by quantitative reverse transcriptase real-time PCR (qRT-PCR), in addition to the assessment of mRNA splicing of the transcription factor X-box binding protein-1 (XBP1). Human neutrophil elastase (HNE) and the transcription factor forkhead box P3 (Foxp3) were also analyzed by immunohistochemistry. Results The increased expression of IL-17 was observed in both intestinal compartments of IBD patients when compared to controls. IFN- γ, TNF-α , IL-10, HNE and Foxp3 were overexpressed in the LP compartment of both IBD patients as compared to controls. An upregulation of IFN-γ and an infiltration of HNE+ cells was found in the SE of patients with UC. Splicing of XBP1 mRNA was recognized in both intestinal compartments of IBD patients when compared to controls. Conclusions In IBD patients, both intestinal compartments are involved in Th17 response, whereas, LP compartment plays a prominent role in Th1 and Treg immune responses. Nevertheless, high level of IFN- γ was found in the SE of UC patients, suggesting that this compartment is involved in the Th1 immune response. Our data also suggested that ER stress signalling is active in both LP and SE compartment of IBD patients, thus advocating that ER stress and immunity are intertwined.

Background: Nearly ten years ago, the WHO reported the increasing prevalence of obesity worldwide as a challenge for public health due the associated adverse consequences. Omic studies demonstrated that microRNA (miRNA) changes in tissues correlate with several diseases, including obesity. Other studies suggested a remarkable stability of miRNA also in blood, emphasing their potential as theranostic agents. Aim: This study investigated the profiles of circulating miRNAs in plasma samples of normal weight (n=159) and overweight/obese (n=149) children participating to the I.Family study, an EC funded study finalized to investigate the etiology of overweight, obesity and related disorders in children of eight European countries (www.ifamilystudy.eu). Differences in miRNA expression patterns with respect to anthropometric and biochemical variables were explored. Results: A high degree of variability in levels of circulating miRNAs was recognised among children from different countries. Several miRNAs differentially expressed in overweight/low grade obesity children were characterized (miR-551a and miR-501-5p up-regulated; miR-10b-5p, miR-191-3p, miR-215-5p and miR-874-3p down-regulated). ROC curves were constructed for confirmed miRNAs. Single miRNAs exhibited low AUC values with the highest values for miR-874-3p and miR-501-5p which in combination provided an interesting value (AUC=0.755). Pearson's analysis confirmed that miR-10b-5p, miR-215-5p, miR-501-5p, miR-551a, and miR-874-3p correlated with BMI z-score. Molecular interactions of obesity-associated miRNAs were also predicted. Computational analysis indicated that miRNAs act as key regulators of metabolism, playing pivotal roles in early stages of obesity by affecting multiple candidate genes. Conclusions: Although causal pathways cannot be definitely inferred it is conceivable that circulating miRNAs may be new biomarkers of early childhood obesity.

RATIONALE In the nuclei of eukaryotic cells, polyamines and phosphate ions self-assemble via ionic interactions and hydrogen bonding, generating three families of supramolecular compounds that have been named large (l-), medium (m-) and small (s-) nuclear aggregates of polyamines (NAPs). In a simulated nuclear environment, polyamines and phosphate ions generate the in vitro NAPs (ivNAPs) that share strict structural and functional analogies with their cellular cognates. Mass spectrometric data are expected to provide important structural details of NAPs/ivNAPs. METHODS We used both electrospray ionization (ESI) and nitrocellulose (NC) matrix-assisted laser desorption ionization time-of-flight (MALDI-TOF) mass spectrometry (MS) to support a variety of analytical techniques previously addressed to structurally characterize NAPs/ivNAPs. RESULTS The dominant m/z values of s-ivNAP (m/z 735, 749, 761) are compatible with a defined set of cyclic or linear aggregates. On the basis of the experimental molecular mass (a cluster centred at m/z 2980), the m-ivNAP corresponds to the supramolecular assembly of four modules of s-ivNAPs. No informative mass spectra were obtained for the l-ivNAP. CONCLUSIONS MS data support the models of NAPs that have been inferred by using an array of analytical techniques. NC MALDI-MS contributed much more effectively than ESI-MS to the structural characterization of ivNAPs. Copyright © 2014 John Wiley & Sons, Ltd.

Polyamines (PAs) are linear polycations that are involved in many biological functions. Putrescine, spermidine and spermine are highly represented in the nucleus of eukaryotic cells and have been the subject of decades of extensive research. Nevertheless, their capability to modulate the structure and functions of DNA has not been fully elucidated. We found that polyamines self-assemble with phosphate ions in the cell nucleus and generate three forms of compounds referred to as Nuclear Aggregates of Polyamines (NAPs), which interact with genomic DNA. In an in vitro setting that mimics the nuclear environment, the assembly of PAs occurs within well-defined ratios, independent of the presence of the DNA template. Strict structural and functional analogies exist between the in vitro NAPs ( iv NAPs) and their cellular homologues. Atomic force microscopy showed that iv NAPs, as theoretically predicted, have a cyclic structure, and in the presence of DNA, they form a tube-like arrangement around the double helix. Features of the interaction between iv NAPs and genomic DNA provide evidence for the decisive role of “natural” NAPs in regulating important aspects of DNA physiology, such as conformation, protection and packaging, thus suggesting a new vision of the functions that PAs accomplish in the cell nucleus.

Natural polyamines (putrescine, spermidine, and spermine) self-assemble in a simulated physiological environment (50 mm sodium phosphate buffer, pH 7.2), generating in vitro nuclear aggregates of polyamines (ivNAPs). These supramolecular compounds are similar in structure and molecular mass to naturally occurring cellular nuclear aggregates of polyamines, and they share the ability of NAPs to interact with and protect the genomic DNA against nuclease degradation. Three main ivNAP compounds were separated by gel permeation chromatography. Their elution was carried out with 50 mm sodium phosphate buffer supplemented with 150 mm NaCl. Freezing and thawing of selected chromatographic fractions obtained by GPC runs in which the mobile phase was sodium phosphate buffer not supplemented with NaCl yielded three different microcrystallites, specifically corresponding to the ivNAPs, all of which were able to bind DNA. In this study, we demonstrated that in vitro self-assembly of polyamines and phosphates is a spontaneous, reproducible and inexpensive event, and provided the indications for the production of the ivNAPs as a new tool for manipulating the genomic DNA machinery.

Nuclear aggregates of polyamines (NAPs) are supramolecular compounds generated by the self-assembly of protonated nuclear polyamines (spermine, spermidine and putrescine) and phosphate ions. In the presence of genomic DNA, the hierarchical process of self-structuring ultimately produces nanotube-like polymers that envelop the double helix. Because of their modular nature and their aggregation-disaggregation dynamics, NAPs confer plasticity and flexibility to DNA. Through the disposition of charges, NAPs also enable a bidirectional stream of information between the genome and interacting moieties. High mobility group (HMG) B1 is a non-histone chromosomal protein that binds to DNA and that influences multiple nuclear processes. Because genomic DNA binds to either NAPs or HMGB1 protein, we explored the ability of in vitro self-assembled NAPs ( iv NAPs) to mediate the DNA-HMGB1 interaction. To this end, we structured DNA-NAPs-HMGB1 and DNA-HMGB1-NAPs ternary complexes in vitro through opportune sequential incubations. Mobility shift electrophoresis and atomic force microscopy showed that the DNA- iv NAPs-HGMB1 complex had conformational assets supposedly more suitable those of the DNA-HGMB1- iv NAPs to comply with the physiological and functional requirements of DNA. Our findings indicated that iv NAPs act as mediators of the DNA-HMGB1 interaction.

Different approaches have been used to study the pattern of cytokines in celiac disease (CD). Laser capture microdissection (LCM) is a powerful tool for the isolation of specific tissue compartments. We aimed to investigate the mucosal immune response that takes place in different intestinal compartments of CD patients, dissected by LCM, analyzing cytokine expression profile. Frozen section of jejunum was obtained from 15 untreated CD and 15 control. Surface epithelium and lamina propria compartment were isolated by LCM. RNA from each LCM sample was extracted and, after a retrotranscription step, messenger RNA levels for MxA, IL-15, TNF-α, IFN-γ, IL-17α, IL-21, IL-10, and TGF-β were determined by quantitative reverse transcriptase-PCR. Increased gene expression levels of MxA, IL-15, TNF-α, IL-10, and TGF-β was observed in the surface epithelium of untreated CD with respect to control. Furthermore, all the cytokines investigated were upregulated in the lamina propria of untreated CD as compared to control. Within the untreated CD group the expression of IL-15 was higher, in the surface epithelium than in the lamina propria, whereas the expression levels of IL-17 and IL-21 were higher in the lamina propria than in the surface epithelium. Finally, high levels of IL-10 and TGF-β were detected in both compartments of untreated CD biopsies. In CD, surface epithelium and lamina propria compartments, play a prominent role in determining innate and adaptive immunity, respectively. Conversely, surface epithelium and lamina propria produce high levels of anti-inflammatory cytokines, suggesting that both compartments are involved in the immunoregulatory response.

A growing interest in developing new strategies for preventing coeliac disease has motivated efforts to identify cereals with null or reduced toxicity. In the current study, we investigate the biological effects of ID331 Triticum monococcum gliadin-derived peptides in human Caco-2 intestinal epithelial cells. Triticum aestivum gliadin derived peptides were employed as a positive control. The effects on epithelial permeability, zonulin release, viability, and cytoskeleton reorganization were investigated. Our findings confirmed that ID331 gliadin did not enhance permeability and did not induce zonulin release, cytotoxicity or cytoskeleton reorganization of Caco-2 cell monolayers. We also demonstrated that ID331 omega-gliadin and its derived peptide omega(105-123) exerted a protective action, mitigating the injury of Triticum aestivum gliadin on cell viability and cytoskeleton reorganization. These results may represent a new opportunity for the future development of innovative strategies to reduce gluten toxicity in the diet of patients with gluten intolerance. (C) 2016 Elsevier Ltd. All rights reserved.

Una sfida ambiziosa nella gestione della malattia celiaca è la ricerca di cereali con nulla o ridotta tossicità. In questo studio, è stato valutato l'effetto biologico di gliadine appartenenti a due cultivar di monococco, ID331 e Monlis, sul modello di cellule Caco-2 differenziate. Inoltre, è stato valutato l'effetto protettivo dell'?-gliadina e del suo peptide ?(105-123) derivativo nel prevenire la tossicità indotta da gliadine di grano tenero. I nostri risultati hanno evidenziato la minore tossicità in termini di permeabilità dei grani ancestrali e un ridotto effetto citotossico dell'ID331. Tali peculiarità permettono di annoverare l'ID331 come la cultivar a ridotta tossicità aprendo così alla possibilità di un suo futuro utilizzo nella dieta per la prevenzione della malattia celiaca.

Taking advantage of the DNA array screening technology, we analysed the effect of sodium butyrate on mRNA transcription in human HT29 colon adenocarcinoma cells. Out of 588 mRNA species analysed, only 119 resulted expressed. Among these, 60 exhibited a variable degree of modulation after butyrate treatment. Genes linked to the cell growth, apoptosis and oxidative metabolism appeared the most significantly affected. Furthermore, many of the differentially expressed genes are transcription factors and this may account for the variability of the biological effects of butyrate. The pattern of butyrate-affected genes may represent a reference in further analyses of gene expression of intestinal cells and tissues.

Polyamines (PA) are believed to protect DNA minimizing the effect of radiation damage either by inducing DNA compaction and aggregation or acting as scavengers of free radicals. Using an in vitro pDNA double strand breakage assay based on gel electrophoretic mobility, we compared the protective capability of PA against ?-radiation with that of compounds generated by the supramolecular self-assembly of nuclear polyamines and phosphates, named Nuclear Aggregates of Polyamines (NAPs). Both unassembled PA and in vitro produced NAPs (ivNAPs) were ineffective in conferring pDNA protection at the sub-mM concentration. Single PA showed an appreciable protective effect only at high (mM) concentrations. However, concentrations of spermine (4+) within a critical range (0.48 - 1 mM) induced pDNA precipitation, an event that was not observed with NAPs-pDNA interaction. We conclude that the interaction of individual PA is ineffective to assure DNA protection, simultaneously preserving the flexibility and charge density of the double strand. Furthermore, data obtained by testing polyamine and ivNAPS with the current radiation-induced DNA damage model support the concept that PA-phosphate aggregates are the only forms through which PA interact with DNA

In the nuclei of eukaryotic cells, polyamines and phosphate ions self-assemble via ionic interactions and hydrogen bonding, generating three families of supramolecular compounds that have been named large (l-), medium (m-) and small (s-) nuclear aggregates of polyamines (NAPs). In a simulated nuclear environment, polyamines and phosphate ions generate the in vitro NAPs (ivNAPs) that share strict structural and functional analogies with their cellular cognates. Mass spectrometric data are expected to provide important structural details of NAPs/ivNAPs.We used both electrospray ionization (ESI) and nitrocellulose (NC) matrix-assisted laser desorption ionization time-of-flight (MALDI-TOF) mass spectrometry (MS) to support a variety of analytical techniques previously addressed to structurally characterize NAPs/ivNAPs.The dominant m/z values of s-ivNAP (m/z 735, 749, 761) are compatible with a defined set of cyclic or linear aggregates. On the basis of the experimental molecular mass (a cluster centred at m/z 2980), the m-ivNAP corresponds to the supramolecular assembly of four modules of s-ivNAPs. No informative mass spectra were obtained for the l-ivNAP.MS data support the models of NAPs that have been inferred by using an array of analytical techniques. NC MALDI-MS contributed much more effectively than ESI-MS to the structural characterization of ivNAPs.

Until recently, the supposed preventive effects of red wine against cardiovascular diseases, the so-called "French Paradox", has been associated to its antioxidant properties. The interest in the anticancer capacity of polyphenols present in red wine strongly increased consequently to the enormous number of studies on resveratrol. In this study, using lyophilized red wine, we present evidence that its anticancer effect in a cellular model is mediated by apoptotic and autophagic cell death. Using a human osteosarcoma cell line, U2Os, we found that the lyophilized red wine was cytotoxic in a dose-dependent manner with a maximum effect in the range of 100-200 mu g/ml equivalents of gallic acid. A mixed phenotype of types I/II cell death was evidenced by means of specific assays following treatment of U2Os with lyophilized red wine, e.g., autophagy and apoptosis. We found that cell death induced by lyophilized red wine proceeded through a mechanism independent from its anti-oxidant activity and involving the inhibition of PI3K/Akt kinase signaling. Considering the relative low concentration of each single bioactive compound in lyophilized red wine, our study suggests the activation of synergistic mechanism able to inhibit growth in malignant cells.

Transport across monolayers of human colon adenocarcinoma (Caco-2) cells represents one of the most widely accepted in vitro models of the intestinal uptake of nutrients and drugs. Herein, the entire panel of peptides produced from caseins (CN) and whey proteins (WP) that survive in vitro sequential gastro-pancreatic digestion and translocate across the Caco-2 monolayers have been characterized by high-performance liquid chromatography (HPLC) and mass spectrometry (MS). Except for traces of casein phosphopeptides, we did not detect any milk-derived peptides with proposed bioactivity. The absorption behavior of two resistant ?-Lactoglobulin (?-Lg) domains, ?- Lg 125-135 and ?-Lg 40-60, was studied in detail using synthetic peptides. The IgE-binding properties of the peptide digests and synthetic peptides recovered from both the apical and basolateral compartments of the monolayers were evaluated by a dot-immunobinding assay using the sera of children (N=5) diagnosed with cow's milk allergy. Outcomes indicated that ?-Lg 127- 135, which is a Caco-2 processed form of ?-Lg 125-135, is a possible "immune sensitizing factors" in vivo. The almost complete loss of the IgE-binding affinity of both CN and WP after enzymatic digestion and transepithelial transport also points out the need of designing in vivo experiments to track the metabolic fate of dietary proteins.

Celiac disease is a chronic enteropathy caused by the ingestion of wheat gliadin and other cereal prolamines. The synthetic peptides 31-43 (P31-43) and 31-49 (P31-49) from A-gliadin are considered to be model peptides for studying innate immunity in celiac disease. Our previous study demonstrated that P31-43 and P31-49 are encrypted within peptide 31- 55 (P31-55), which is naturally released from gastropancreatic digestion and is not susceptible to hydrolysis by brush border membrane enzymes. Here, we analyzed the permeability of P31-55 through the epithelial cell layer of confluent Caco-2 cells using high-performance liquid chromatography, mass spectrometry, and fluorescence-activated cell sorting. Twenty-three percent of the P31-55 added to the apical chamber was transported to the basolateral chamber after 4 h of incubation without being degraded by hydrolysis. Treatment of Caco-2 cells with whole gliadin digests extracted from a common wheat cultivar increased the epithelial P31-55 translocation by approximately 35%. Moreover, we observed an atypical chromatographic profile consisting of a double peak. Chromatography using different column temperatures and circular dichroism highlighted the presence of more conformational structures around the amide bond of the two adjacent prolines 38 and 39. These findings confirm that P31-55 is gastrointestinally resistant and is permeable across a Caco-2 monolayer. Moreover, we hypothesize that the various conformations of P31-55 may play a role in the activation of innate immunity.

Background: Celiac disease (CD) is a chronic enteropathy caused by the ingestion of wheat gliadin and other cereal prolamines. Cereals of baking quality with reduced or absent toxicity are actively required as alternative therapy to a gluten-free diet for CD patients. T. monococcum (AA genome) wheat species are among the most promising suitable candidates. Under physiological conditions, intestinal epithelia are almost impermeable to macromolecules such as gliadin. Several studies reported that CD is a condition in which paracellular permeability is enhanced and the integrity of the tight junction system is compromised so favoring the interaction of gliadin peptides with sub-epithelial compartment. In this contest, zonulin, a recently described intestinal protein involved in tight junctions regulation, is responsible for the altered permeability in CD subjects. Objective: In the present study we investigate the effects on permeability of gliadins derived from two T. monococcum cultivars (ID331 and Monlis) using Caco-2 cells differentiated onto insert chambers. Experiments were performed in comparison with T. aestivum (italian cultivar) as the positive control. Methods: Alcohol soluble gliadins were processed using an in vitro digestion model mimicking in vivo gastric-pancreatic intestinal processes. The human Caco-2 cell line was used as a model of the gut epithelium to predict the physiological behavior. Cells were 21 days differentiated onto insert chambers. Paracellular permeability of Caco-2 cells was evaluated by measuring the Transepithelial Electrical Resistance (TEER) at appropriate time-points after treatment. The release of zonulin protein was also investigated by ELISA. Results: As previously demonstrated, Triticum aestivum gliadin induced a significant increase in Caco-2 cell permeability. On the contrary, TEER value was slightly reduced in the presence of Monlis, and remained unchanged with ID331 gliadin (Figure). Moreover, both T. monococcum cultivars did not affect Caco-2 cell viability. Preliminary data suggest that T. monococcum exert a reduced zonulin release with respect to T. aestivum.

In the cell nucleus, putrescine, spermidine, and spermine self-assemble with phosphate ions to generate three forms of compounds, named nuclear aggregates of polyamines (NAPs), which may interact with DNA. In an in vitro setting mimicking the cell nucleus milieu, this molecular aggregation occurs within well-defined ratios. Structural and functional analogies exist between the in vitro NAPs (ivNAPs) and their extractive homologues. The present Article reports images of ivNAPs at different resolution levels. Independent of the DNA template, ivNAPs become hierarchically stacked to produce ultimately macroscopic filamentous structures. The ivNAP-DNA complexes arranged in long and repetitive structures that displayed the self-similar features of natural fractals when dehydrated onto glass slides. Atomic force microscopy showed that ivNAPs have a cyclic structure and dispose around the DNA in a tube-like arrangement. Overall, the images indicate that these aggregates envelope the genomic DNA, thus proving that NAPs play a crucial role in DNA compaction and functioning.

S-Adenosylhomocysteine hydrolase from Sulfolobus solfataricus, a thermoacidophilic archaeon optimally growing at 87 degrees C, has been purified to homogeneity. The specific activity of the homogeneous enzyme is 161 nmol of S-adenosylhomocysteine formed per min per mg of protein, and the overall yield, by immunoaffinity purification, is 51%. The enzyme has a molecular mass of 190 kDa, is composed of four identical subunits (subunit mass 47 kDa), and contains four molecules of tightly-bound NAD+ per tetramer of which about 40% is in the reduced form. Physico-chemical features, including amino-acid composition and secondary structure, are reported. The pure protein, used to raise specific rabbit antisera, shows immunological properties different from other S-adenosylhomocysteine-metabolizing enzymes. The enzyme is thermophilic with an optimum temperature of 75 degrees C, and shows an apparent melting temperature of 95 degrees C by measuring its residual activity after 10 min incubation at increasing temperatures.

Increasing evidence supports the health benefi ts of moderate consumption of alcohol as part of a healthy lifestyle. Numerous studies suggest that moderate drinking of beer is associated with lower rates of cardiovascular disease, cancer and osteoporosis. Recent researches in bioactive principles revealed many notable properties of hop compounds. Scientifi c evidence has accumulated over the last years pointing to the potential anticancer activities of selected hop-derived beer constituents. A generalized radical scavenging activity was described for most beer polyphenolic components, and a protection against DNA oxidative damage was reported. In this chapter, we will discuss the potential chemopreventive role and helpful effects on health of beer and its constituents compared to wine.

Selectively targeting death receptors to trigger apoptosis in cancer cells appears ideal in cancer therapy. The tumor necrosis factor-related apoptosis-inducing ligand (TRAIL/Apo2L) is of great interest since it has been shown to predominantly kill cancer cells without toxic effects on normal counterparts, thus representing a promising anticancer agent. However, resistance towards TRAIL/Apo2L treatment has also been described. To overcome this obstacle, co-administration of TRAIL/Apo2L plus several compounds, including histone deacetylase inhibitors (HDACi), has been attempted as a strategy to restore cancer cell sensitivity to TRAIL-induced apoptosis. In recent years, the clinical application of HDACi has been largely explored for their ability to modulate gene transcription, block cell division cycle, inhibit cell proliferation, induce cellular differentiation and apoptosis.The ability of valproic acid (VPA), a well-known HDACi, to sensitise the K562 cell line, derived from a human leukemia, to TRAIL/Apo2L-mediated apoptosis was evaluated. VPA was selected since it is currently used in clinical practice and its pharmacokinetic, pharmacodynamic and bioavailability are known.When applied with TRAIL/Apo2L, VPA increased cell death and caspase-3 activity by 4-fold compared to the treatment with TRAIL/Apo2L alone. VPA sensitized K562 cells to TRAIL/Apo2L-mediated apoptosis by increasing the expression of DR4 and DR5 by 3- and 14-fold respectively. In addition, VPA per se, in the absence of TRAIL/Apo2L, reduced the expression of antiapoptotic factors, such as c-FLPs, associated with DISC, and Bcl-2/Bcl-X(L), associated with mitochondria, acting on both extrinsic and intrinsic apoptotic pathways.Our results demonstrated the ability of VPA to sensitize TRAIL/Apo2L-resistant cells to apoptosis, thus providing an attractive approach for the treatment of leukemias and other proliferative malignancies.

Increasing evidence supports the health benefi ts of moderate consumption of alcohol as part of a healthy lifestyle. Numerous studies suggest that moderate drinking of beer is associated with lower rates of cardiovascular disease, cancer and osteoporosis. Recent researches in bioactive principles revealed many notable properties of hop compounds. Scientifi c evidence has accumulated over the last years pointing to the potential anticancer activities of selected hop-derived beer constituents. A generalized radical scavenging activity was described for most beer polyphenolic components, and a protection against DNA oxidative damage was reported. In this chapter, we will discuss the potential chemopreventive role and helpful effects on health of beer and its constituents compared to wine.

BACKGROUND: Selectively targeting death receptors to trigger apoptosis in cancer cells appears ideal in cancer therapy. The tumor necrosis factor-related apoptosis-inducing ligand (TRAIL/Apo2L) is of great interest since it has been shown to predominantly kill cancer cells without toxic effects on normal counterparts, thus representing a promising anticancer agent. However, resistance towards TRAIL/Apo2L treatment has also been described. To overcome this obstacle, co-administration of TRAIL/Apo2L plus several compounds, including histone deacetylase inhibitors (HDACi), has been attempted as a strategy to restore cancer cell sensitivity to TRAIL-induced apoptosis. In recent years, the clinical application of HDACi has been largely explored for their ability to modulate gene transcription, block cell division cycle, inhibit cell proliferation, induce cellular differentiation and apoptosis. MATERIALS AND METHODS: The ability of valproic acid (VPA), a well-known HDACi, to sensitise the K562 cell line, derived from a human leukemia, to TRAIL/Apo2L-mediated apoptosis was evaluated. VPA was selected since it is currently used in clinical practice and its pharmacokinetic, pharmacodynamic and bioavailability are known. RESULTS: When applied with TRAIL/Apo2L, VPA increased cell death and caspase-3 activity by 4-fold compared to the treatment with TRAIL/Apo2L alone. VPA sensitized K562 cells to TRAIL/Apo2L-mediated apoptosis by increasing the expression of DR4 and DR5 by 3- and 14-fold respectively. In addition, VPA per se, in the absence of TRAIL/Apo2L, reduced the expression of antiapoptotic factors, such as c-FLPs, associated with DISC, and Bcl-2/Bcl-X(L), associated with mitochondria, acting on both extrinsic and intrinsic apoptotic pathways. CONCLUSION: Our results demonstrated the ability of VPA to sensitize TRAIL/Apo2L-resistant cells to apoptosis, thus providing an attractive approach for the treatment of leukemias and other proliferative malignancies.

In a previous work, taking advantage of the gene-array screening technology, we analysed the effects of histone deacetylase (HDAC) inhibitor sodium butyrate (NaBt), on gene transcription in HT29 human adenocarcinoma cell line. In this study, we focused our attention on p55CDC/Cdc20 gene, whose expression was dramatically reduced by NaBt treatment. Mammalian p55CDC/Cdc20 interacts with the anaphase promoting complex/cyclosome (APC/C), and is involved in regulating anaphase onset and late mitotic events. Using NaBt and trichostatin A (TSA), a member of the HDAC inhibitor family, we showed that both HDAC inhibitors totally downregulated p55CDC/Cdc20 transcription and expression. Cell cycle analysis demonstrated that NaBt arrested HT29 cells in G0/G1 phase, while TSA caused a double block in G0/G1 and G2/M phases. Moreover, p55CDC/Cdc20 showed maximal expression in S and G2/M phases of HT29 cell division cycle. Based on this evidence, and by means of specific cell cycle modulators, such as nocodazole and hydroxyurea, we demonstrated that both TSA and NaBt were responsible for loss of p55CDC/Cdc20 expression, but with different mechanisms of action. Taken together, these results suggest that targeting molecules involved in spindle mitotic checkpoint, such as p55CDC/Cdc20, might account for the high cytotoxicity of HDAC inhibitors versus malignant cells.

An impressive number of studies have suggested that red wine can be considered the protective beverage of choice against chronic and degenerative pathologies. Only few and controversial data are available on a potential, similar role for beer, which represents a more cost-effective, safe, and widely available beverage. Starting from the evidence that many antioxidant compounds present in red wine are also present at similar or even higher concentrations in beers, we first screened 48 commercially available beers and selected one (Mrt-HP) with very high polyphenol concentration and antioxidant activity estimated by ferric reducing antioxidant power. We demonstrated that a lyophilized preparation of Mrt-HP beer was cytotoxic with respect to a beer with low polyphenolic content (Trt-LP) when assayed on HL-60 human leukemia cell line. We measured a 60% decrease in cell viability at a polyphenol concentration of 250 microM quercetin equivalents. We also demonstrated that Mrt-HP cytotoxicity was not an artifact due to cell growth conditions because addition of Mrt-HP extracts to cell medium generated peroxide levels indistinguishable from controls. By means of cytofluorimetric analysis of pre-G1 population and caspase 3 activation, we demonstrated that Mrt-HP extracts activated apoptosis in HL-60 cell line. Finally, we found that the concentration of quercetin, resveratrol, and gallic acid in Mrt-HP was 10, 4.6, and 4.6-fold higher, respectively, than in Trt-LP, suggesting that the presence of these molecules might be responsible for the observed cytotoxicity. These data, together with the low in vivo beer toxicity reported in the literature, suggest a possible chemopreventive role for this beverage that requires further studies in animal models.

We previously demonstrated that quercetin, a naturally occurring flavonoid with strong antioxidant properties, was able to enhance programmed cell death in HPB-acute lymphoblastic leukemia (ALL) cell line, derived from a human tymoma, when associated with the agonistic anti-CD95 monoclonal antibody. Here, we report that HPB-ALL cells are normally resistant to CD95-mediated apoptosis, and quercetin is able to sensitize this cell line through a mechanism independent of its antioxidant properties. In fact, other compounds structurally and functionally similar to quercetin, when associated with anti-CD95 antibody did not induce any CD95-mediated apoptosis, still maintaining their antioxidant capacity. We found that quercetin effects are mediated by the activation of PKCalpha. Treatment of HPB-ALL cells with quercetin slightly decreased PKCalpha activity, but when the flavonoid was associated with anti-CD95, the kinase activity increased by 12-fold with respect to the treatment with quercetin. In addition, overexpression of PKCalpha induced programmed cell death in the absence of any additional stimulus, while a kinase-defective mutant of PKCalpha was ineffective. Our data confirm the involvement of specific PKC isoforms in CD95 signaling and suggest, for the first time, that quercetin targets this pathway increasing apoptogenic response in a cell line resistant to CD95-mediated apoptosis.

The protective effect of red wine polyphenols against hydrogen peroxide (H2O2)-induced oxidation was investigated in normal human erythrocytes (RBCs). RBCs, preincubated with micromolar amounts of wine extract and challenged with H2O2, were analyzed for reactive oxygen species (ROS), hemolysis, methemoglobin production, and lipid peroxidation. All these oxidative modifications were prevented by incubating the RBCs with oak barrel aged red wine extract (SD95) containing 3.5 mM gallic acid equivalent (GAE) of phenolic compounds. The protective effect was less apparent when RBCs were incubated with wines containing lower levels of polyphenols. Furthermore, resveratrol and quercetin, well known red wine antioxidants, showed lower antioxidant properties compared with SD95, indicating that interaction between constituents may bring about effects that are not necessarily properties of the singular components. Our findings demonstrate that the nonalcoholic components of red wine, mainly polyphenols, have potent antioxidant properties, supporting the hypothesis of a beneficial effect of red wine in oxidative stress in human system. © Elsevier Science Inc. 2000