Endotoxins Induced ECM-Receptor Interaction Pathway Signal Effect on the Function of MUC2 in Caco2/HT29 Co-Culture Cells.

Endotoxins are toxic substances that widely exist in the environment and can enter the intestine with food and other substances. Intestinal epithelial cells are protected by a mucus layer that contains MUC2 as its main structural component. However, a detailed understanding of the mechanisms involved in the function of the mucus barrier in endotoxin penetration is lacking. Here, we established the most suitable proportion of Caco-2/HT-29 co-culture cells as a powerful tool to evaluate the intestinal mucus layer. Our findings significantly advance current knowledge as focal adhesion and ECM-receptor interaction were identified as the two most significantly implicated pathways in MUC2 small interfering RNA (siRNA)-transfected Caco-2/HT-29 co-culture cells after 24 h of LPS stimulation. When the mucus layer was not intact, LPS was found to damage the tight junctions of Caco-2/HT29 co-cultured cells. Furthermore, LPS was demonstrated to inhibit the integrin-mediated focal adhesion structure and damage the matrix network structure of the extracellular and actin microfilament skeletons. Ultimately, LPS inhibited the interactive communication between the extracellular matrix and the cytoskeleton for 24 h in the siMUC2 group compared with the LPS(+) and LPS(-) groups. Overall, we recognized the potential of MUC2 as a tool for barrier function in several intestinal bacterial diseases.

MicroRNA 181a-2-3p Alleviates the Apoptosis of Renal Tubular Epithelial Cells via Targeting GJB2 in Sepsis-Induced Acute Kidney Injury.

Acute kidney injury (AKI) is the most common complication of sepsis. MicroRNAs (miRNAs) play important roles in the sepsis-induced AKI. This paper aimed to explore the role of miRNA 181a-2-3p (miR-181a-2-3p) in the sepsis-induced AKI and the underlying mechanism. Our results revealed that miR-181a-2-3p showed low expression levels in patients with sepsis and mouse models undergoing cecal ligation and puncture (CLP). The addition of miR-181a-2-3p antagonists aggravated the sepsis-induced kidney injuries and inflammatory response in CLP mouse models, as suggested by hematoxylin and eosin (H&E) staining and quantitative real-time PCR (qRT-PCR). In addition, miR-181a-2-3p mimic alleviated the lipopolysaccharide (LPS)-induced inflammatory response, along with apoptosis of TCMK-1. Moreover, results from the GSE46955 data set indicated that GJB2 was highly expressed in septic patients but lowly expressed after recovery. Further, the dual-luciferase reporter assay and RNA immunoprecipitation (RIP) assay were carried out, which confirmed that GJB2 was a target of miR-181a-2-3p, and overexpression of GJB2 reversed the anti-inflammatory and antiapoptotic effects of miR-181a-2-3p mimic on the LPS-induced sepsis cell models. In conclusion, miR-181a-2-3p alleviates the inflammatory response and cell apoptosis of septic patients and animal models by upregulating GJB2 expression, which may provide a new therapeutic strategy for sepsis.

Anti-inflammatory potential of invasive sun corals (Scleractinia: Tubastraea spp.) from Brazil: alternative use for management?

OBJECTIVES: The objective was to analyse the anti-inflammatory potential of the invasive coral species Tubastraea coccinea and Tubastraea tagusensis. METHODS: Methanolic extracts, fractions and synthesized compounds were evaluated for their anti-inflammatory ability, and their composition was elucidated through chemical analysis. KEY FINDINGS: The genus Tubastraea (Order Scleractinia, Family Dendrophylliidae) (known as sun corals) presents compounds with pharmacological value. The introduction of these azooxanthellate hard corals into Brazil, initially in Rio de Janeiro state, occurred through their fouling of oil and gas platforms from the Campos oil Basin. The two invasive species have successfully expanded along the Brazilian coast and threaten endemic species and biodiversity. The HPLC-MS and GC-MS data suggest the presence of aplysinopsin analogues (alkaloids). Anti-inflammatory activity was observed in all samples tested in in-vivo assays, especially in T. coccinea. The ethyl acetate fraction from this sample was more effective in in-vitro assays for anti-inflammatory activity. Depending on the concentration, this fraction showed cytotoxic responses. CONCLUSIONS: These species have potential pharmacological use, and considering their invasive nature, this study presents a potential alternative use, which may enhance the management of this biological invasion.

Toll-Like Receptor 4 Signaling Licenses the Cytosolic Transport of Lipopolysaccharide From Bacterial Outer Membrane Vesicles.

Outer membrane vesicles (OMVs), released by variety of bacteria, are membrane-enclosed entities enriched in microbial components, toxins, and virulent factors. OMVs could deliver lipopolysaccharide (LPS) into the cytosol of host cells and subsequently activate caspase-11, which critically orchestrates immune responses and mediates septic shock. Although it is known that caspase-11 is activated by intracellular LPS, how OMVs deliver LPS into the cytosol remains largely unknown. Here we show that the activation of toll-like receptor 4 (TLR4), a LPS receptor on the cytoplasmic membrane, licenses macrophages to transport LPS from OMVs into the cytosol through TIR domain-containing adaptor-inducing interferon-ß (TRIF). TRIF-mediated cytosolic delivery of LPS from OMVs depends on the production of type 1 interferon and the expression of guanylate-binding proteins (GBPs). Deletion of TRIF or GBPs prevents pyroptosis and lethality induced by OMVs or OMVs-releasing Escherichia coli. Together, these findings provide novel insight into how host coordinates extracellular and intracellular LPS sensing to orchestrate immune responses during gram-negative bacterial infection.

Prolyl hydroxylases positively regulated LPS-induced inflammation in human gingival fibroblasts via TLR4/MyD88-mediated AKT/NF-κB and MAPK pathways.

OBJECTIVES: Prolyl hydroxylases (PHDs) play essential roles in oxygen-sensing system, whereas the effects of PHDs on inflammation have not been totally uncovered. Our study aimed to investigate the role of PHDs in lipopolysaccharide (LPS)-induced inflammation of human gingival fibroblasts (HGFs) and clarify the potential mechanisms. MATERIALS AND METHODS: A pan hydroxylase inhibitor, dimethyloxallyl glycine (DMOG), and RNA interference were used to explore the role of PHDs in inflammation. Cytotoxic effect of DMOG was determined by cell-counting kit-8 and flow cytometry respectively. The secretion levels of IL-6 and IL-8 were assessed by ELISA. The mRNA levels of inflammatory cytokines, Toll-like receptor (TLR) 4 and MyD88 were evaluated by quantitative real-time PCR. The activation of NF-κB, mitogen-activated protein kinase (MAPK) and PI3K/AKT pathways were detected by western blot and the nuclear translocation of NF-κB p65 was examined by immunofluorescence. Downregulation of PHD1 and PHD2 was performed with siRNA transfection. RESULTS: Dimethyloxallyl glycine inhibited LPS-induced inflammatory cytokine, TLR4 and MyD88 expression in gene level and the elevated secretion of IL-6 and IL-8 was also downregulated. Additionally, LPS-induced activation of NF-κB, MAPK and AKT pathways was abolished by DMOG treatment. Importantly, LPS-induced inflammatory cytokine expression was merely suppressed by PHD2 knockdown. CONCLUSIONS: Prolyl hydroxylases acted as a positive regulator in LPS-induced inflammation of HGFs via TLR4/MyD88-mediated NF-κB, MAPK and AKT signalling pathways and PHD2 among three isoforms was principally responsible for the effects.

Distinct pattern of immune tolerance in dendritic cells treated with lipopolysaccharide or lipoteichoic acid.

Cytokine induction is often critical for the host defense during acute immune responses while, if not tightly regulated, it may cause an immunological pathology coincident with tissue damage. Despite the fact that gram-positive bacterial infection has become increasingly prevalent, immune modulation induced by lipoteichoic acid (LTA), the major cell wall component of gram-positive bacteria has not been studied thoroughly at the cellular level. In the current study, tolerance induction in mouse bone marrow-derived dendritic cells (BMDCs) treated with single or repeated stimulation of Staphylococcus aureus LTA was compared with those of Escherichia coli lipopolysaccharide (LPS). The results showed that repeated LTA stimulation significantly suppressed pro-inflammatory cytokine (TNF-α and IL-6) production in BMDCs, comparable to that of LPS, but with less extent, down-regulated IL-10 and enhanced the inhibitory molecule, LAG-3-associated protein (LAP). Furthermore, we observed a sustained expression of unique negative regulators, Toll interacting protein (TOLLIP) and Indoleamine 2,3-dioxygenase (IDO), in BMDCs treated with LTA. A transient hyporesponsiveness period appeared when DCs were treated repeatedly with LTA or LPS showing a distinctive pattern. Intriguingly, LPS exposure induced cross tolerance to LTA while LTA exposure did not to LPS, implicating that a distinct signaling components are involved in response to LTA. Collectively, a distinct immune regulation appeared to be responsible for the LPS- and LTA-induced tolerance on cytokine production, expression of surface markers and intracellular proteins.

Retinoic acid-mediated anti-inflammatory responses in equine immune cells stimulated by LPS and allogeneic mesenchymal stem cells.

Retinoic acid (RA), an active metabolite of vitamin A, has shown potential therapeutic immunomodulatory properties. Allogeneic mesenchymal stem cells (MSCs)-based therapy is an effective approach to induce tissue healing and regeneration in many equine orthopedic conditions. However, MSCs-based therapies induced inflammatory responses in vivo. This study aimed to: 1. Determine the effect of RA cell culture treatment on inflammatory responses of lipopolysaccharides (LPS)- and allogeneic MSCs-stimulated peripheral blood mononuclear cells (PBMCs). 2. Determine the effect of RA on stimulated MSCs viability and morphology. Allogeneic MSCs-stimulated PBMCs had significant decreases in the anti-inflammatory cytokines (IL-10, IL-1ra, TGF-ß1), increases in the pro-inflammatory mediators (IL-1ß, IL-6, TNF-α, SAA), and increases of CD14 and MHC II percent positive cells compared to LPS- and non-stimulated PBMCs. Retinoic acid treatment of LPS- and allogeneic MSCs-stimulated PBMCs counterbalanced the induced inflammatory responses. Moreover, RA significantly improved the viability and morphology of stimulated MSCs. These findings highlighted the potential complications of equine allogeneic MSCs-based therapies and the immuno-modulatory effect of RA on equine stimulated cells. In conclusion, the use of RA to ameliorate allogeneic MSCs therapy associated inflammation may offer advantages that would require further investigations.

Proteomic analysis of Arabidopsis plasma membranes reveals lipopolysaccharide-responsive changes.

Plant plasma membranes (PMs) contain pattern recognition receptors (PRRs), lately believed to be associated within multicomponent complexes, which perceive microbe-associated molecular pattern (MAMP) molecules like lipopolysaccharides (LPSs) and result in signal transduction events that lead to activated immune defense responses. As such, Arabidopsis thaliana leaves were treated with LPS from Escherichia coli (LPSE.coli) over time, and PM fractions isolated and evaluated using gel-based and subsequent mass spectrometry approaches for identification of LPS-responsive proteins. From the identified protein bands and spots, it is concluded that perception of hexaacylated LPS and resulting signal transduction occurs via PM-associated protein(s), amongst others, receptor-like kinases (RLKs) including G-type lectin S-receptor kinase and BAK1, and mostly likely within specialized perception domains.

Inflammation induced by inhaled lipopolysaccharide depends on particle size in healthy volunteers.

AIMS: In drug development, the anti-inflammatory properties of new molecules in the lung are currently tested using the inhaled lipopolysaccharide (LPS) model. The total and regional lung bioavailability of inhaled particles depends significantly on their size. The objective of the present study was to compare inflammatory responses in healthy volunteers after the inhalation of LPS of varying droplet size. METHODS: Three nebulizers were characterized by different droplet size distributions [mean mass median aerodynamic diameters: Microcirrus (2.0 µm), MB2 (3.2 µm) and Pari (7.9 µm)]. Participants inhaled three boluses of a 20 µg (technetium 99 m-labelled) solution of LPS, randomly delivered by each nebulizer. We measured the lung deposition of the nebulized LPS by gamma-scintigraphy, while blood and sputum biomarkers were evaluated before and after challenges. RESULTS: MB2 and Pari achieved greater lung deposition than Microcirrus [171.5 (±72.9) and 217.6 (±97.8) counts pixel-1 , respectively, vs. 67.9 (±20.6) counts pixel-1 ; P < 0.01]. MB2 and Pari caused higher levels of blood C-reactive protein and more total cells and neutrophils in sputum compared with Microcirrus (P < 0.05). C-reactive protein levels correlated positively with lung deposition (P < 0.01). CONCLUSIONS: Inhalation of large droplets of LPS gave rise to greater lung deposition and induced a more pronounced systemic and bronchial inflammatory response than small droplets. The systemic inflammatory response correlated with lung deposition. NCT01081392.

The cell wall component lipoteichoic acid of Staphylococcus aureus induces chemokine gene expression in bovine mammary epithelial cells.

Staphylococcus aureus (SA) is a major cause of bovine mastitis, but its pathogenic mechanism remains poorly understood. To evaluate the role of lipoteichoic acid (LTA) in the immune or inflammatory response of SA mastitis, we investigated the gene expression profile in bovine mammary epithelial cells stimulated with LTA alone or with formalin-killed SA (FKSA) using cap analysis of gene expression. Seven common differentially expressed genes related to immune or inflammatory mediators were up-regulated under both LTA and FKSA stimulations. Three of these genes encode chemokines (IL-8, CXCL6 and CCL2) functioning as chemoattractant molecules for neutrophils and macrophages. These results suggest that the initial inflammatory response of SA infection in mammary gland may be related with LTA induced chemokine genes.

Neuronal nitric oxide synthase has a role in the detrimental effects of lipopolysaccharide on spatial memory and synaptic plasticity in rats.

BACKGROUND: The role of neuronal nitric oxide synthase (nNOS) in lipopolysaccharide (LPS)-induced memory and synaptic plasticity impairment was investigated. METHODS: The rats were divided and treated as follows: (1) control (saline), (2) LPS, (3) 7NI (7-nitroindazole as a nNOS inhibitor)-LPS and (4) 7NI. RESULTS: In a Morris water maze, the LPS group took a longer amount of time and traveled a greater distance to reach the platform, this was prevented by 7NI. Malondialdehyde (MDA) and nitric oxide (NO) metabolites in the hippocampus of the LPS group were higher while the total thiol, superoxide dismutase and catalase were lower than that of the controlled specimen. Pre-treatment using 7NI prevented the changes in the biochemical criteria. The slope and amplitude of the field excitatory post-synaptic potential (fEPSP) in the LPS group decreased, whereas in 7NI-LPS group they increased. CONCLUSION: It is suggested that inhibition of nNOS by 7NI improves the deleterious effects of LPS by reducing NO metabolites and the brain tissues oxidative damage.

Characteristics of Lung Injury in Rats after Inhalation of Ultradisperse Bacterial LPS in Lipophilic and Hydrophilic Phases.

We compared cellular and tissue reactions of the lungs in Wistar rats after inhalation of LPS from E. coli 0128: B12 in the form of ultradispersion in water-salt phase and lipid phase. The estimated dose of the toxin was 200 mg/kg in both series. The content of LPS and TNF-α in lung homogenates, bronchoalveolar fluid, and blood serum was determined 3, 8, and 24 h after inhalation, morphological changes in the lungs were analyzed. Inhalation of LPS in the lipid phase was accompanied by its less intensive accumulation in the lung tissue and bloodstream, and more pronounced accumulation in the bronchoalveolar fluid as well as less intense release of TNF-α in comparison with the effects of LPS in water-salt phase. Macrophage reaction, leukocyte infiltration of the interalveolar septa, and reduction of α-antitrypsin in the lung tissue was more pronounced in series with inhalation with LPS ultradispersions in water-salt phase and lipid phase, and damage to the alveolar epithelium, in the series with the inhalation of the lipid phase.

Combined effect of rifampicin-induced P-glycoprotein expression and lipopolysaccharide-induced intestinal sepsis on the effective permeability and pharmacokinetics of an anti-malarial candidate CDRI 97/78 in rats.

1. The study aimed to investigate the influences on the pharmacokinetics (PK) of an anti-malarial drug 97/78 in rats pretreated with orally administered rifampicin and bacterial endotoxin lipopolysaccharide (LPS). 2. In-situ intestinal absorption studies were conducted on rats pretreated with rifampicin and LPS or both to estimate effective permeability (Peff) of 97/78. In-vivo studies were then conducted to explore 97/78 PK profile under these conditions. In-situ studies revealed that Peff value decreased to 64% (2.7 ± 0.6) × 10(-4 )cm/s in rats pretreated with rifampicin. This decrease was further enhanced very significantly to 4.5% (0.19 ± 0.03) × 10(-4 )cm/s in rats pretreated both with rifampicin and LPS (p<0.05). For PK studies, it was found that relative bioavailability (RB) was decreased to 22.56% in rifampicin-pretreated rats and to 8.02% in rats pretreated both with rifampicin and LPS. About five-fold decrease was observed in systemic exposure (AUC) of 97/78 in rifampicin-pretreated rats. This decrease was further augmented to 12-fold upon rifampicin and LPS pretreatment. 3. Orally administered rifampicin decreased the concentration of 97/78 in circulation. This decrease was further enhanced significantly to a very low level by LPS-induced intestinal sepsis.

Antigen presenting cells targeting and stimulation potential of lipoteichoic acid functionalized lipo-polymerosome: a chemo-immunotherapeutic approach against intracellular infectious disease.

Antigen presenting cells (APC) are well-recognized therapeutic targets for intracellular infectious diseases, including visceral leishmaniasis. These targets have raised concerns regarding their potential for drug delivery due to overexpression of a variety of receptors for pathogen associated molecular pathways after infection. Since, lipoteichoic acid (LTA), a surface glycolipid of Gram-positive bacteria responsible for recognition of bacteria by APC receptors that also regulate their activation for pro-inflammatory cytokine secretion, provides additive and significant protection against parasite. Here, we report the nanoarchitechture of APC focused LTA functionalized amphotericin B encapsulated lipo-polymerosome (LTA-AmB-L-Psome) delivery system mediated by self-assembly of synthesized glycol chitosan-stearic acid copolymer (GC-SA) and cholesterol lipid, which can activate and target the chemotherapeutic agents to Leishmania parasite resident APC. Greater J774A and RAW264.7 macrophage internalization of FITC tagged LTA-AmB-L-Psome compared to core AmB-L-Psome was observed by FACSCalibur cytometer assessment. This was further confirmed by higher accumulation in macrophage rich liver, lung and spleen during biodistribution study. The LTA-AmB-L-Psome overcame encapsulated drug toxicity and significantly increased parasite growth inhibition beyond commercial AmB treatment in both in vitro (macrophage-amastigote system; IC50, 0.082 ± 0.009 µg/mL) and in vivo (Leishmania donovani infected hamsters; 89.25 ± 6.44% parasite inhibition) models. Moreover, LTA-AmB-L-Psome stimulated the production of protective cytokines like interferon-γ (IFN-γ), interleukin-12 (IL-12), tumor necrosis factor-α (TNF-α), and inducible nitric oxide synthase and nitric oxide with down-regulation of disease susceptible cytokines, like transforming growth factor-ß (TGF-ß), IL-10, and IL-4. These data demonstrate the potential use of LTA-functionalized lipo-polymerosome as a biocompatible lucrative nanotherapeutic platform for overcoming toxicity and improving drug efficacy along with induction of robust APC immune responses for effective therapeutics of intracellular diseases.

Distress do paciente oncológico: prevalência e fatores associados na opinião de familiares / Distress of cancer patients: prevalence and associated factors in the opinion of family / Angustia de los pacientes con cáncer: prevalencia y factores asociados en la opinión de la familia

Este estudo verificou a prevalência e fatores associados ao distress de pacientes oncológicos, na opinião de familiares. Foram entrevistados 140 familiares responsáveis pelo cuidado de pacientes com câncer. O Termômetro de Distress foi adaptado para uso em familiares. Estes consideraram que 72,9% dos pacientes estavam com distress relacionado a preocupações (80,4%), nervosismo (78,4%), tristeza (74,5%), dor (67,6%), fadiga (67,6%) e problemas com alimentação (57,8%). Modelos de regressão logística hierárquica mostraram que, enquanto familiares do sexo masculino (OR=0,025) e idades mais avançadas (OR=0,006 a 0,059) tiveram menor risco de perceber o distress, indivíduos protestantes, comparados a católicos, tiveram chance 12,77 vezes maior de percebê-lo. Quanto aos fatores associados, nervosismo (OR=10,8) contribuiu significativamente mais com a percepção de distress pelos familiares quando comparado a fadiga (OR=3,38) ou ter plano de saúde privado (OR=2,55). Familiares podem ser grandes aliados na avaliação e acompanhamento do distress de pacientes com câncer.

The study aimed to verify the opinion of family members about distress on cancer patients and the factors associated with it. Interviews with 140 family members of cancer patients were conducted. The Distress Thermometer was adapted to be used with family members. Approximately 72.9% of patients were considered in distress, related to concern (80.4%), nervousness (78.4%), sadness (74.5%), pain (67.6%), fatigue (67.6%) and problems with eating (57.8%). The hierarchical logistic regression models showed that while male (OR=0.025) and older ages (OR=0.006 to 0.059) had lower risk of perceiving the distress, individuals Protestants, compared to Catholics, were 12.77 times more likely to perceive it. About the associated factors, nervousness (OR=10.8) contributed significantly more to the perception of distress for family members when compared to fatigue (OR=3.38) or have private health insurance (OR=2.55). Family can be great allies in the evaluation and monitoring of distress in patients with cancer.

Este estudio examinó la prevalencia y los factores asociados con el distress de los pacientes de cáncer, de acuerdo con los familiares. Fueran entrevistados 140 cuidadores familiares de pacientes con cáncer. El Termómetro de Distress fue adaptado para el uso en los familiares. Ellos encontraron que el 72,9% de los pacientes estaban con distress relacionado con preocupaciones (80,4%), nerviosismo (78,4%), tristeza (74,5%), dolor (67,6%), fatiga (67, 6%) y problemas con la alimentación (57,8%). Modelos de regresión logística jerárquica mostraran que, mientras los familiares de sexo masculino (OR=0,025) y de edades más avanzadas (OR=0,006 a 0,059) tuvieron un menor riesgo de percibir el distress, los individuos protestantes, comparados a los católicos, tuvieron oportunidad 12,77 veces mayor para percibirlo. En cuanto a los factores asociados, el nerviosismo (OR=10,8) contribuyó significativamente más a la percepción del distress de los familiares, en comparación con la fatiga (OR=3,38) o tener un seguro de salud privado (OR=2,55). Familiares pueden ser grandes aliados en la evaluación y el seguimiento de sufrimiento en los pacientes con cáncer.

Dual labeling of lipopolysaccharides for SPECT-CT imaging and fluorescence microscopy.

Lipopolysaccharides (LPS) or endotoxins are amphipathic, pro-inflammatory components of the outer membrane of Gram-negative bacteria. In the host, LPS can trigger a systemic inflammatory response syndrome. To bring insight into in vivo tissue distribution and cellular uptake of LPS, dual labeling was performed with a bimodal molecular probe designed for fluorescence and nuclear imaging. LPS were labeled with DOTA-Bodipy-NCS, and pro-inflammatory properties were controlled after each labeling step. LPS were then radiolabeled with (111)In and subsequently injected intravenously into wild-type, C57B16 mice, and their in vivo behavior was followed by single photon emission computed tomography coupled with X-ray computed tomography (SPECT-CT) and fluorescence microscopy. Time course of liver uptake of radiolabeled LPS ((111)In-DOTA-Bodipy-LPS) was visualized over a 24-h period in the whole animal by SPECT-CT. In complementary histological analyses with fluorescent microscopy, the bulk of injected (111)In-DOTA-Bodipy-LPS was found to localize early within the liver. Serum kinetics of unlabeled and DOTA-Bodipy-labeled LPS in mouse plasma were similar as ascertained by direct quantitation of ß-hydroxymyristate, and DOTA-Bodipy-LPS was found to retain the potent, pro-inflammatory property of the unlabeled molecule as assessed by serum cytokine assays. It is concluded that the dual labeling process, involving the formation of covalent bonds between a DOTA-Bodipy-NCS probe and LPS molecules is relevant for imaging and kinetic analysis of LPS biodistribution, both in vivo and ex vivo. Data of the present study come in direct and visual support of a lipopolysaccharide transport through which pro-inflammatory LPS can be transported from the periphery to the liver for detoxification. The (111)In-DOTA-Bodipy-LPS probe arises here as a relevant tool to identify key components of LPS detoxification in vivo.

RhoB is involved in lipopolysaccharide-induced inflammation in mouse in vivo and in vitro

Small GTPase RhoB has been well documented in regulating cell adhesion, motility, proliferation, and survival, but to date, there is little information about the relationship between RhoB and inflammation. In this study, the mRNA and protein levels of RhoB were induced by lipopolysaccharide (LPS) in RAW264.7 cells determined by real-time PCR and Western blot. The upregulation of RhoB by LPS was also observed in mouse peritoneal macrophages and in mouse lung, liver, and kidney. RhoB overexpression by transfecting with wild RhoB plasmid increased the secretion of tumor necrosis factor alpha (TNF-Alpha) and nitric oxide (NO) in RAW264.7 cells, while RhoB knockdown by RNA interference decreased the secretion of TNF-Alpha and NO in RAW264.7 cells. TNF-Alpha and NO synthase are the target genes of nuclear factor-kappaB (NF-KappaB), and overexpression of RhoB increased, whereas inhibition of RhoB decreased the basal and LPS-activated transcriptional activity of NF-KappaB in the cells. These results demonstrated that LPS induced RhoB expression in mouse in vivo and in vitro and in RAW264.7 cells, and the role of RhoB on LPS-induced secretion of TNF-Alpha and NO was at least partly mediated via NF-KappaB. These results indicated that RhoB was involved in LPS-induced inflammation in mouse in vivo and in vitro

Deoxynivalenol and E.coli lipopolysaccharide alter epithelial proliferation and spatial distribution of apical junction proteins along the small intestinal axis.

We investigated a proposed synergistic effect of deoxynivalenol (DON) and lipopolysaccharides (LPS) on small intestinal architecture and epithelial barrier integrity in pigs. Crypt depth and intestinal cell proliferation were analyzed, as well as expression of zonula occludens protein-1 (ZO-1) and ß-catenin of the apical junction complex along the small intestine. Barrows (26.2±4.1 kg) were fed restrictedly either a control diet (CON) or a diet naturally contaminated with 3.1 mg DON/kg feed (DON) for 37 d. At d 37, the control group was infused for 1 h either with 100 µg/kg BW of DON (CON-DON, n=6), 7.5 µg/kg BW of LPS (CON-LPS, n=6), a combination of both (CON-DON+LPS, n=7), or 0.9% NaCl (CON-CON, n=6) and the DON group with 7.5 µg/kg BW of LPS (DON-LPS, n=8) or 0.9% NaCl (DON-CON, n=6). Pigs were euthanized 3.25 h after start of infusion. Immunohistochemistry (5'-bromo-2'-deoxyuridine for proliferation) and immunofluorescence (ZO-1 and ß-catenin) from duodenum, proximal jejunum, mid-jejunum, proximal ileum, and terminal ileum were analyzed for crypt depth, cell proliferation, and apical junction proteins. Duodenal crypts were deeper compared with the other 4 intestinal regions, and proximal jejunal crypts were deeper than those of mid-jejunum and proximal ileum (P<0.001). Epithelial proliferation showed a bell-shaped distribution along the small intestinal axis. Duodenal proliferating cells had the least number compared with jejunal sections and proximal ileum (P<0.001). Neither DON nor LPS affected these variables. Zonula occludens-1 displayed a distinct spatial distribution in the epithelium with an apical and a cytosolic component. Apical expression of ZO-1 was severely damaged in the mid-jejunum (P<0.001) of CON-DON compared with animals treated with LPS. Also, in all animals receiving LPS systemically, the cytosolic ZO-1 fraction in the 3 upper gut sections disappeared completely. This effect was independent of DON presence. Control pigs had a greater basolateral ß-catenin accumulation (P<0.05) in the cells, whereas the protein distribution did not differ in CON-DON pigs. In conclusion, results of this experiment demonstrated that epithelial proliferation has a distinct pattern along the small intestine and is not necessarily positively linked to crypt depth in pigs. Furthermore, results indicate that LPS changed the spatial distribution of ZO-1. A synergistic effect of DON and LPS on intestinal architecture could not be verified in the present study.

A pathogenetic link between non-alcoholic fatty liver disease and celiac disease.

Non-alcoholic fatty liver disease (NAFLD) has recently been recognized as the leading cause of the abnormalities in the liver function tests in the Western countries. Celiac disease (CD) is a permanent immunological intolerance to gluten proteins in genetically predisposed individuals. CD has been reported in 4-13 % of the cases with steatohepatitis, although the pathogenesis of the liver steatosis in CD patients is unclear. Based on the literature data, it can be concluded that the inclusion of serological markers of CD should be a part of the general workup in the patients with steatosis when other causes of the liver disease are excluded and in the patients with NAFLD when metabolic risk factors are not evident.

Nadph oxidase regulates alveolar epithelial sodium channel activity and lung fluid balance in vivo via O⁻2 signaling.

To define roles for reactive oxygen species (ROS) and epithelial sodium channel (ENaC) in maintaining lung fluid balance in vivo, we used two novel whole animal imaging approaches. Live X-ray fluoroscopy enabled quantification of air space fluid content of C57BL/6J mouse lungs challenged by intratracheal (IT) instillation of saline; results were confirmed by using conventional lung wet-to-dry weight ratios and Evans blue as measures of pulmonary edema. Visualization and quantification of ROS produced in lungs was performed in mice that had been administered a redox-sensitive dye, hydro-Cy7, by IT instillation. We found that inhibition of NADPH oxidase with a Rac-1 inhibitor, NSC23766, resulted in alveolar flooding, which correlated with a decrease in lung ROS production in vivo. Consistent with a role for Nox2 in alveolar fluid balance, Nox2(-/-) mice showed increased retention of air space fluid compared with wild-type controls. Interestingly, fluoroscopic analysis of C57BL/6J lungs IT instilled with LPS showed an acute stimulation of lung fluid clearance and ROS production in vivo that was abrogated by the ROS scavenger tetramethylpiperidine-N-oxyl (TEMPO). Acute application of LPS increased the activity of 20 pS nonselective ENaC channels in rat type 1 cells; the average number of channel and single-channel open probability (NPo) increased from 0.14 ± 0.04 to 0.62 ± 0.23. Application of TEMPO to the same cell-attached recording caused an immediate significant decrease in ENaC NPo to 0.04 ± 0.03. These data demonstrate that, in vivo, ROS has the capacity to stimulate lung fluid clearance by increasing ENaC activity.