Administration of reconstituted polyphenol oil bodies efficiently suppresses dendritic cell inflammatory pathways and acute intestinal inflammation

Polyphenols are natural compounds capable of interfering with the inflammatory pathways of several in vitro model systems. In this study, we developed a stable and effective strategy to administer polyphenols to treat in vivo models of acute intestinal inflammation. The in vitro suppressive properties of several polyphenols were first tested and compared for dendritic cells (DCs) production of inflammatory cytokines. A combination of the polyphenols, quercetin and piperine, were then encapsulated into reconstituted oil bodies (OBs) in order to increase their stability. Our results showed that administration of low dose reconstituted polyphenol OBs inhibited LPS-mediated inflammatory cytokine secretion, including IL-6, IL-23, and IL-12, while increasing IL-10 and IL-1Rα production. Mice treated with the polyphenol-containing reconstituted OBs (ROBs) were partially protected from dextran sodium sulfate (DSS)-induced colitis and associated weight loss, while mortality and inflammatory scores revealed an overall anti-inflammatory effect that was likely mediated by impaired DC immune responses. Our study indicates that the administration of reconstituted quercetin and piperine-containing OBs may represent an effective and potent anti-inflammatory strategy to treat acute intestinal inflammation

Polyphenol administration impairs T-cell proliferation by imprinting a distinct dendritic cell maturational profile

Currently little is known as to how nutritionally derived compounds may affect dendritic cell (DC) maturation and potentially prevent inappropriate inflammatory responses that are characteristic of chronic inflammatory syndromes. Previous observations have demonstrated that two polyphenols Quercetin and Piperine delivered through Reconstituted Oil Bodies (ROBs-QP) can influence DC maturation in response to LPS leading to a modulated inflammatory response. In the present study, we examined the molecular effects of ROBs-QP exposure on DC differentiation in mice and identified a unique molecular signature in response to LPS administration that potentially modulates DC maturation and activity in inflammatory conditions. Following LPS administration, ROBs-QP exposed DCs expressed an altered molecular profile as compared with control DCs, including cytokine and chemokine production, chemokine receptor repertoire and antigen presentation ability. In vivo ROBs-QP administration suppresses antigen specific T-cell division in the draining lymph nodes resulting from a reduced ability to create stable immunological synapse. Our data demonstrate that polyphenols exposure can drive DCs towards a new anti-inflammatory molecular profile capable of dampening the inflammatory response, highlighting their potential as complementary nutritional approaches in the treatment of chronic inflammatory syndromes. This article is protected by copyright. All rights reserved

Preliminary results of shaking-table tests on a full-scale flat-bottom manufactured steel silo filled with wheat

This paper presents the preliminary results of a series of shaking-table tests on a full-scale flat-bottom manufactured steel silo filled with a granular material. A 3.64 m-diameter 5.5 m-height cylindrical silo has been tested in fixed-base and isolated-base configurations. The isolators put between the table and the r.c. plate are Curved Surface Sliders friction pendulum devices. Mono-axial shaking-table tests have been performed using random signals, low-frequency sinusoidal inputs and earthquake records (both artificial and real). The results are relevant to: the identification of the basic dynamic properties (frequency, damping ratio, amplification) of the grain-silo system, the experimental assessment of the static pressure (during filling phase) and seismic dynamic over-pressures and the effectiveness of the isolation system at the base of the silo

ROBs-QP administration promotes a unique cytokine profile in LPS-treated DCs.

<p>BMDCs were exposed to different ROBs-QP concentrations on day 5 and 7. LPS [1 µg/ml] was administered on day 8, and 24 h later SNs were collected. Cytokine protein levels were measured by ELISA. Data are shown as mean ± S.D. of five independent experiments. Statistically significant differences were considered when **P<0.01; ***P<0.001 between control (LPS, no polyphenols) and LPS-ROBS-QP-treated cells.</p

Characterization of polyphenol-embedded ROBs.

<p>A) model structure of a natural oil body: external PL monolayer, embedded proteins (<i>i.e</i>. oleosin) and TAGs; Piperine and quercetin were encapsulated in the core. B and D) CLSM micrograph of empty ROBs and quercetin encapsulated ROBs imaged by transmitted light. C and E) LSM micrograph of empty ROBs and ROBs quercetin imaged by fluorescence light using an excitation wavelength of 488 nm and emission recorded with a 505–530 nm filter set. F) Degradation profiles of free (squares) and NE (circles) quercetin incubated in 0.1 M phosphate buffer pH 7 at 37°C in the dark for different times; HPLC chromatograms of free quercetin (12.5 µM) incubated with 0.1 M phosphate buffer pH 7 in the dark at 37°C after 0 h (G), 4 h (H) and 48 h (I) compared to HPLC chromatograms of quercetin encapsulated ROBs (12.5 µM) treated in the same experimental conditions at 48 h (2 days, L), 144 h (6 days, M) and 432 h (18 days, N).</p

ROBs-QP <i>in vivo</i> administration reduced expression of COX2 in colon lysates even in absence of the epithelial cells layer.

<p>(A) Histology from ROBs-QP treated mice indicates signs of inflammation and infiltrating granulocytes in the colon of vehicle- and ROBs-QP-treated mice. (B) Western blot staining of colon lysates obtained from mice treated as previously described. Reduced expression of COX2 can be observed with or without epithelial cells from colon lysates of ROBs-QP-treated colons. The constitutive isoform COX1 showed no detectable differences.</p

ROB-embedded polyphenol mix interferes with production of LPS-mediated cytokines from DCs.

<p>ROB-embedded piperine (ROBs-P), quercetin (ROBs-Q) or a mix of the two (ROBs-QP) were administered on day 5 and 7 [25 µM] to DC cultures. LPS [1 µg/ml] was administered on day 8. SNs were collected 24 h later and TNFα and IL-6 content evaluated by ELISA. Data are shown as mean ± S.D. of five independent experiments; **P<0.01, ***P<0.001.</p

Modulated activation of pro-inflammatory MAPK p38 signaling and inducible COX-2 on ROBs-QP treated DCs.

<p>DCs were cultured in the presence of either ROBs-P, ROBs-Q or ROBs-QP as mentioned previously; empty ROBs were used as control. LPS (A) or PG (B) was administered at indicated time points. DC lysates were subjected to immunoblotting with antibodies to detect total and phosphorylated forms of p38 MAPK and COX-2. Representative immunoblots from at least three independent experiments are shown for each condition. Each bar represents the mean ± SEM of densitometric analyses for phosphorylated proteins normalized to their respective total forms; *P<0.05, **P<0.01 vs. basal conditions.</p

Administration of Reconstituted Polyphenol Oil Bodies Efficiently Suppresses Dendritic Cell Inflammatory Pathways and Acute Intestinal Inflammation

Polyphenols are natural compounds capable of interfering with the inflammatory pathways of several in vitro model systems. In this study, we developed a stable and effective strategy to administer polyphenols to treat in vivo models of acute intestinal inflammation. The in vitro suppressive properties of several polyphenols were first tested and compared for dendritic cells (DCs) production of inflammatory cytokines. A combination of the polyphenols, quercetin and piperine, were then encapsulated into reconstituted oil bodies (OBs) in order to increase their stability. Our results showed that administration of low dose reconstituted polyphenol OBs inhibited LPS-mediated inflammatory cytokine secretion, including IL-6, IL-23, and IL-12, while increasing IL-10 and IL-1Rα production. Mice treated with the polyphenol-containing reconstituted OBs (ROBs) were partially protected from dextran sodium sulfate (DSS)-induced colitis and associated weight loss, while mortality and inflammatory scores revealed an overall anti-inflammatory effect that was likely mediated by impaired DC immune responses. Our study indicates that the administration of reconstituted quercetin and piperine-containing OBs may represent an effective and potent anti-inflammatory strategy to treat acute intestinal inflammation

Plankton dynamics across the freshwater, transitional and marine research sites of the LTER-Italy Network. Patterns, fluctuations, drivers

A first synoptic and trans-domain overview of plankton dynamics was conducted across the aquatic sites belonging to the Italian Long-Term Ecological Research Network (LTER-Italy). Based on published studies, checked and complemented with unpublished information, we investigated phytoplankton and zooplankton annual dynamics and long-term changes across domains: from the large subalpine lakes to mountain lakes and artificial lakes, from lagoons to marine coastal ecosystems. This study permitted identifying common and unique environmental drivers and ecological functional processes controlling seasonal and long-term temporal course. The most relevant patterns of plankton seasonal succession were revealed, showing that the driving factors were nutrient availability, stratification regime, and freshwater inflow. Phytoplankton and mesozooplankton displayed a wide interannual variability at most sites. Unidirectional or linear long-term trends were rarely detected but all sites were impacted across the years by at least one, but in many case several major stressor(s): nutrient inputs, meteo-climatic variability at the local and regional scale, and direct human activities at specific sites. Different climatic and anthropic forcings frequently co-occurred, whereby the responses of plankton communities were the result of this environmental complexity. Overall, the LTER investigations are providing an unparalleled framework of knowledge to evaluate changes in the aquatic pelagic systems and management options