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

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

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