Transcriptional complex assembly represented in SBGN PD

This poster shows how transcriptional complex assembly can be represented in SBGN Process Description language. Example: LPS-induced TNF-alpha enhancer complex formation

Environmental Circadian Disruption Elevates the IL-6 Response to Lipopolysaccharide in Blood

The immune system is regulated by circadian clocks within the brain and immune cells. Environmental circadian disruption (ECD), consisting of a 6-h phase advance of the light:dark cycle once a week for 4 weeks, elevates the inflammatory response to lipopolysaccharide (LPS) both in vivo and in vitro. This indicates that circadian disruption adversely affects immune function; however, it remains unclear how the circadian system regulates this response under ECD conditions. Here, we develop an assay using ex vivo whole-blood LPS challenge to investigate the circadian regulation of immune responses in mice and to determine the effects of ECD on these rhythms. LPS-induced IL-6 release in whole blood was regulated in a circadian manner, peaking during subjective day under both entrained and free-running conditions. This LPS-induced IL-6 release rhythm was associated with daily variation in both white blood cell counts and immune cell responsiveness. ECD increased the overall level of LPS-induced IL-6 release by increasing immune cell responsiveness and not by affecting immune cell number or the circadian regulation of this rhythm. This indicates that ECD produces pathological immune responses by increasing the proinflammatory responses of immune cells. Also, this newly developed whole blood assay can provide a noninvasive longitudinal method to quantify potential health consequences of circadian disruption in humans

Bisdemethoxycurcumin and Its Cyclized Pyrazole Analogue Differentially Disrupt Lipopolysaccharide Signalling in Human Monocyte-Derived Macrophages

open11noSeveral studies suggest that curcumin and related compounds possess antioxidant and anti-inflammatory properties including modulation of lipopolysaccharide- (LPS-) mediated signalling in macrophage cell models. We here investigated the effects of curcumin and the two structurally unrelated analogues GG6 and GG9 in primary human blood-derived macrophages as well as the signalling pathways involved. Macrophages differentiated from peripheral blood monocytes for 7 days were activated with LPS or selective Toll-like receptor agonists for 24 h. The effects of test compounds on cytokine production and immunophenotypes evaluated as CD80+/CCR2+ and CD206+/CD163+ subsets were examined by ELISA and flow cytometry. Signalling pathways were probed by Western blot. Curcumin (2.5–10 μM) failed to suppress LPS-induced inflammatory responses. While GG6 reduced LPS-induced IκB-α degradation and showed a trend towards reduced interleukin-1β release, GG9 prevented the increase in proinflammatory CD80+ macrophage subset, downregulation of the anti-inflammatory CD206+/CD163+ subset, increase in p38 phosphorylation, and increase in cell-bound and secreted interleukin-1β stimulated by LPS, at least in part through signalling pathways not involving Toll-like receptor 4 and nuclear factor-κB. Thus, the curcumin analogue GG9 attenuated the LPS-induced inflammatory response in human blood-derived macrophages and may therefore represent an attractive chemical template for macrophage pharmacological targeting.openTedesco, Serena; Zusso, Morena; Facci, Laura; Trenti, Annalisa; Boscaro, Carlotta; Belluti, Federica; Fadini, Gian Paolo; Skaper, Stephen D.; Giusti, Pietro; Bolego, Chiara; Cignarella, AndreaTedesco, Serena; Zusso, Morena; Facci, Laura; Trenti, Annalisa; Boscaro, Carlotta; Belluti, Federica; Fadini, Gian Paolo; Skaper, Stephen D.; Giusti, Pietro; Bolego, Chiara; Cignarella, Andre

LPS-induced Pellino3 degradation is mediated by p62-dependent autophagy

Background: In macrophages Toll-like receptor 4 (TLR4) is activated in response to lipopolysaccharide (LPS) and induces proinflammatory cytokine expression. Therefore, mechanisms terminating proinflammatory gene expression are important. Autophagy plays a central role in controlling innate immune responses by lysosomal degradation of signaling proteins, thus contributing to the resolution of inflammation. Autophagic proteins like p62 directly interact with molecules involved in the TLR4-signaling pathway, but a correlation with the IRAK E3 ligase and scaffold protein Pellino3 remains obscure. Hence, we are interested in elucidating the function of Pellino3 to prove our hypothesis that it is a key regulator in the TLR4-signaling cascade. Methods: We used the cecal ligation and puncture (CLP) mouse model causing polymicrobial sepsis to analyze Pellino3 protein and mRNA expression. Furthermore, we induced endotoxemia in RAW264.7 mouse macrophages by LPS treatment to verify in vivo experiments. Lentiviral Pellino3 knockdown in RAW264.7 macrophages was used for cytokine measurements at mRNA level. To analyze potential Pellino3 binding partners in TLR4-signaling by mass spectrometry (MS), we overexpressed FLAG-tagged Pellino3 in RAW264.7 macrophages, treated cells for 3, 6 and 24 hours with LPS and immunoprecipitated Pellino3 via its FLAG-tag. To consider Pellino3 degradation as a result of p62-mediated autophagy, we transiently knocked down p62 by siRNA in RAW264.7 macrophages and also pharmacologically blocked LPS-induced autophagy by Bafilomycin A1. Results: We demonstrated Pellino3 protein degradation in primary CD11b+ splenocytes after 24 hours following CLP operation and confirmed this in RAW264.7 macrophages after 24-hour LPS stimulation. Knockdown of Pellino3 attenuates proinflammatory cytokines, for example IL-6 mRNA, after 6 hours of LPS. Furthermore, we found by MS and verifying immunoprecipitation experiments that p62 is a Pellino3 binding partner, thus targeting Pellino3 for degradation. In line, both p62 knockdown and Bafilomycin A1 treatment prevent Pellino3 degradation, supporting an autophagic mechanism. Conclusion: Our observations highlight a regulatory role of Pellino3 on TLR4 signaling. Thus, antagonism of Pellino3 in the hyperinflammatory phase of sepsis may counteract the cytokine storm. Furthermore, stabilization of Pellino3 by inhibition of autophagy in the hypoinflammatory phase of sepsis may improve immunity. In consideration of these two conflictive sepsis phases, modulation of Pellino3 may provide a new strategy for the development of a therapy approach in sepsis

Effect of fish oil on lipopolysaccharide-induced hydroxyapatite loss in rat alveolar bone: A Preliminary Study

Dietary fish oil has been shown to inhibit bone resorption and, therefore, the aim of the present study was to test the hypothesis that fish oil alters lipopolysaccharide (LPS)-induced hydroxyapatite loss in rat alveolar bone. Rats were divided into four groups. The animals injected with saline or Escherichia coli-derived LPS into the maxillary alveolar mucosa on the buccoapical site of the molar region daily for 8 days were served as a negative or positive control, respectively. Other groups of animals were injected with LPS and orally treated with fish oil at the same day with or after LPS injection. The results of the present study showed that the hydroxyapatite contents of alveolar bone in rats treated with fish oil at the same day with or before LPS injection were significantly higher than those in rats injected with LPS alone, but still lower than those in untreated animals. Therefore, the present study suggests that oral treatment with fish oil may reduce LPS-induced hydroxyapatite loss in rat alveolar bon

N-Acetylcysteine Suppresses LPS-Induced Pathological Angiogenesis

Background/Aims: Angiogenesis is a key feature during embryo development but is also part of the pathogenesis of cancer in adult life. Angiogenesis might be modulated by inflammation. Methods: We established an angiogenesis model in chick chorioallantoic membrane (CAM) induced by the exposure of lipopolysaccharide (LPS), and analyzed the effects of the antioxidant N-acetylcysteine (NAC) on angiogenesis in this model as well as on the expression of key genes known to involved in the regulation of angiogenesis. Results: Treatment with NAC was able to normalize LPS induced angiogenesis and restore the LPS-induced damage of vascular epithelium in chick CAM. Using quantitative PCR, we showed that NAC administration normalized the LPS induced expression of Keap1-Nrf2 signaling and oxidative stress key enzyme gene expressions (SOD, GPx and YAP1). Conclusion: We established a LPS-induced angiogenesis model in chick CAM. NAC administration could effectively inhibit LPS-induced angiogenesis and restore the integrity of endothelium on chick CAM. LPS exposure caused an increased expression of genes involved in oxidative stress in chick CAM. NAC administration could abolish this effect

Extracellular ATP drives systemic inflammation, tissue damage and mortality

Systemic inflammatory response syndromes (SIRS) may be caused by both infectious and sterile insults, such as trauma, ischemia-reperfusion or burns. They are characterized by early excessive inflammatory cytokine production and the endogenous release of several toxic and damaging molecules. These are necessary to fight and resolve the cause of SIRS, but often end up progressively damaging cells and tissues, leading to life-threatening multiple organ dysfunction syndrome (MODS). As inflammasome-dependent cytokines such as interleukin-1 beta are critically involved in the development of MODS and death in SIRS, and ATP is an essential activator of inflammasomes in vitro, we decided to analyze the ability of ATP removal to prevent excessive tissue damage and mortality in a murine LPS-induced inflammation model. Our results indeed indicate an important pro-inflammatory role for extracellular ATP. However, the effect of ATP is not restricted to inflammasome activation at all. Removing extracellular ATP with systemic apyrase treatment not only prevented IL-1 beta accumulation but also the production of inflammasome-independent cytokines such as TNF and IL-10. In addition, ATP removal also prevented systemic evidence of cellular disintegration, mitochondrial damage, apoptosis, intestinal barrier disruption and even mortality. Although blocking ATP receptors with the broad-spectrum P2 purinergic receptor antagonist suramin imitated certain beneficial effects of apyrase treatment, it could not prevent morbidity or mortality at all. We conclude that removal of systemic extracellular ATP could be a valuable strategy to dampen systemic inflammatory damage and toxicity in SIRS

Immune cells and preterm labour:do invariant NKT cells hold the key?

We have developed our original made-to-measure (M2M) algorithm, PRIMAL, with the aim of modelling the Galactic disc from upcoming Gaia data. From a Milky Way like N-body disc galaxy simulation, we have created mock Gaia data using M0III stars as tracers, taking into account extinction and the expected Gaia errors. In PRIMAL, observables calculated from the N-body model are compared with the target stars, at the position of the target stars. Using PRIMAL, the masses of the N-body model particles are changed to reproduce the target mock data, and the gravitational potential is automatically adjusted by the changing mass of the model particles. We have also adopted a new resampling scheme for the model particles to keep the mass resolution of the N-body model relatively constant. We have applied PRIMAL to this mock Gaia data and we show that PRIMAL can recover the structure and kinematics of a Milky Way like barred spiral disc, along with the apparent bar structure and pattern speed of the bar despite the galactic extinction and the observational errors

A mucin-like peptide from Fasciola hepatica instructs dendritic cells with parasite specific Th1-polarizing activity

Fasciolosis is a trematode zoonosis of interest in public health and cattle production. We report here the immunostimulatory effect of a 66 mer mucin-like peptide from Fasciola hepatica (Fhmuc), which synergizes with lipopolysaccharide (LPS) to promote dendritic cell (DC) maturation, endowing these cells with Th1-polarizing capacity. Exposure of DCs to Fhmuc in presence of LPS induced enhanced secretion of pro-inflammatory cytokines and expression of co-stimulatory molecules by DCs, promoting their T cell stimulatory capacity and selectively augmenting IFN- secretion by allogeneic T cells. Furthermore, exposure of DCs to Fhmuc augmented LPS-induced Toll-like receptor (TLR) 4 expression on the cell surface. Finally, Fhmuc-conditioned DCs induced parasite specific-adaptive immunity with increased levels of IFN-gamma secreted by splenocytes from vaccinated animals, and higher parasite-specific IgG antibodies. However, DC-treated Fhmuc conferred modest protection against F. hepatica infection highlighting the potent immuno-regulatory capacity of the parasite. In summary, this work highlights the capacity of a mucin-derived peptide from F. hepatica to enhance LPS-maturation of DCs and induce parasite-specific immune responses with potential implications in vaccination and therapeutic strategies.Fil: Noya, Verónica. Universidad de la República; UruguayFil: Brossard, Natalie. Universidad de la República; UruguayFil: Rodríguez, Ernesto. Universidad de la República; UruguayFil: Dergan Dylon, Leonardo Sebastian. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Biología y Medicina Experimental. Fundación de Instituto de Biología y Medicina Experimental. Instituto de Biología y Medicina Experimental; ArgentinaFil: Carmona, Carlos. Universidad de la República; UruguayFil: Rabinovich, Gabriel Adrián. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Biología y Medicina Experimental. Fundación de Instituto de Biología y Medicina Experimental. Instituto de Biología y Medicina Experimental; ArgentinaFil: Freire, Teresa. Universidad de la República; Urugua