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Sample records for coli endotoxin lipopolysaccharide

  1. The roots of Nardostachys jatamansi inhibits lipopolysaccharide-induced endotoxin shock.

    PubMed

    Bae, Gi-Sang; Seo, Sang-Wan; Kim, Min-Sun; Park, Kyoung-Chel; Koo, Bon Soon; Jung, Won-Seok; Cho, Gil-Hwan; Oh, Hyun Cheol; Yun, Seung-Won; Kim, Jong-Jin; Kim, Sung Gyu; Hwang, Sung-Yeon; Song, Ho-Joon; Park, Sung-Joo

    2011-01-01

    Nardostachys jatamansi (NJ) has been used in the treatment of inflammatory diseases. However, it is not clear how NJ produces anti-inflammatory effects. In the present study, using an experimental model of lipopolysaccharide (LPS)-induced endotoxin shock, the protective effects and mechanisms of action of NJ were investigated. The water extract of roots of NJ was administrated to mice orally (1, 5, and 10 mg/kg) 1 h after or before LPS challenge. The administration of NJ inhibited LPS-induced endotoxin shock and the production of inflammatory mediators, such as interleukin (IL)-1?, IL-6, tumor necrosis factor (TNF)-?, and interferon (IFN)-?/?. Murine peritoneal macrophages were used to determine the production of inflammatory mediators. In peritoneal macrophages, NJ also inhibited LPS-induced production of inflammatory mediators, such as IL-1?, IL-6, TNF-?, and IFN-?/?. In addition, NJ reduced the activation of mitogen-activated protein kinases (MAPKs) and the level of expression of interferon regulatory factor (IRF)-1 and IRF-7 mRNA. Furthermore, post-treatment with NJ reduced LPS-induced endotoxin shock and the production of inflammatory mediators. These results suggest that NJ inhibits endotoxin shock by inhibiting the production of IL-1?, IL-6, TNF-?, and IFN-?/? through the inhibition of MAPKs activation and IRF induction. PMID:20799070

  2. Synthesis, characterization and immunological properties of Escherichia coli 0157:H7 lipopolysaccharide- diphtheria toxoid conjugate vaccine

    PubMed Central

    Rokhsartalab-Azar, Shadi; Shapouri, Reza; Rahnema, Mehdi; Najafzadeh, Faezeh

    2015-01-01

    Background and Objective: Escherichia coli O157:H7, an emerging pathogen, causes severe enteritis and the extraintestinal complication of hemolytic-uremic syndrome. The goal of this study was to evaluate the conjugate of E. coli O157: H7 lipopolysaccharide (LPS) with diphtheria toxoid (DT) as a candidate vaccine in mice model. Material and Methods: LPS from E. coli O157:H7 was extracted by hot phenol method and then detoxified. Purified LPS was coupled to DT with adipic acid dihydrazide (ADH) as a spacer and 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide (EDAC) as a linker. The coupling molar ratio of LPS to DT was 3:1. Clinical evaluation of E. coli O157:H7 LPS-DT conjugate was also performed. Results: The conjugate was devoid of endotoxin activity and indicated 0.125 U/ml of D-LPS. Mice immunization with D-LPS DT conjugate elicited fourfold higher IgG antibody in comparison to D-LPS. Also, in vivo protection of mice with conjugate provided high protection against the LD50 of E. coli O157:H7, which indicated a good correlation with the IgG titer. Conclusion: Our results showed that the suggested vaccine composed of E. coli O157:H7 LPS and DT had a significant potential to protect against E. coli infections. PMID:26668702

  3. TOPOMIMETICS OF AMPHIPATHIC ?-SHEET AND HELIX-FORMING BACTERICIDAL PEPTIDES NEUTRALIZE LIPOPOLYSACCHARIDE ENDOTOXINS

    PubMed Central

    Chen, Xuemei; Dings, Ruud P.M.; Nesmelova, Irina; Debbert, Stefan; Haseman, Judith R.; Maxwell, Jacques; Hoye, Thomas R.; Mayo, Kevin H.

    2008-01-01

    Release of lipopolysaccharide (LPS) endotoxin from Gram negative bacterial membranes triggers macrophages to produce large quantities of cytokines that can lead to septic shock and eventual death. Agents that bind to and neutralize LPS may provide a means to clinically prevent septic shock upon bacterial infection. Previously, we reported the design of antibacterial helix peptide SC4 and ?-sheet-forming ?pep peptides that neutralize LPS in vitro. We hypothesized that the ability of these and other such peptides to neutralize LPS rested in the common denominator of positively charged amphipathic structure. Here, we describe the design and synthesis of non-peptide, calixarene-based helix/sheet topomimetics that mimic the folded conformations of these peptides in their molecular dimensions, amphipathic surface topology, and compositional properties. From a small library of topomimetics, we identified several compounds that neutralize LPS in the 10?8 M range, making them as effective as bactericidal/permeability increasing (BPI) protein and polymyxin B. In an endotoxemia mouse model, three of the most in vitro effective topomimetics are shown to be at least partially protective against challenges of LPS from different bacterial species. NMR studies provide mechanistic insight by suggesting the site of molecular interaction between topomimetics and the lipid A component of LPS, with binding being mediated by electrostatic and hydrophobic interactions. This research contributes to the development of pharmaceutical agents against endotoxemia and septic shock. PMID:17181157

  4. Capture of Lipopolysaccharide (Endotoxin) by the Blood Clot: A Comparative Study

    PubMed Central

    Armstrong, Margaret T.; Rickles, Frederick R.; Armstrong, Peter B.

    2013-01-01

    In vertebrates and arthropods, blood clotting involves the establishment of a plug of aggregated thrombocytes (the cellular clot) and an extracellular fibrillar clot formed by the polymerization of the structural protein of the clot, which is fibrin in mammals, plasma lipoprotein in crustaceans, and coagulin in the horseshoe crab, Limulus polyphemus. Both elements of the clot function to staunch bleeding. Additionally, the extracellular clot functions as an agent of the innate immune system by providing a passive anti-microbial barrier and microbial entrapment device, which functions directly at the site of wounds to the integument. Here we show that, in addition to these passive functions in immunity, the plasma lipoprotein clot of lobster, the coagulin clot of Limulus, and both the platelet thrombus and the fibrin clot of mammals (human, mouse) operate to capture lipopolysaccharide (LPS, endotoxin). The lipid A core of LPS is the principal agent of gram-negative septicemia, which is responsible for more than 100,000 human deaths annually in the United States and is similarly toxic to arthropods. Quantification using the Limulus Amebocyte Lysate (LAL) test shows that clots capture significant quantities of LPS and fluorescent-labeled LPS can be seen by microscopy to decorate the clot fibrils. Thrombi generated in the living mouse accumulate LPS in vivo. It is suggested that capture of LPS released from gram-negative bacteria entrapped by the blood clot operates to protect against the disease that might be caused by its systemic dispersal. PMID:24282521

  5. Gram-negative endotoxin lipopolysaccharide induces cardiac hypertrophy: detrimental role of Na(+)-Ca(2+) exchanger.

    PubMed

    Magi, Simona; Nasti, Annamaria Assunta; Gratteri, Santo; Castaldo, Pasqualina; Bompadre, Stefano; Amoroso, Salvatore; Lariccia, Vincenzo

    2015-01-01

    Several molecular pathways involved in the development of cardiac hypertrophy are triggered by perturbation of intracellular Ca(2+) homeostasis. Within the heart, Na(+)/Ca(2+) exchanger 1 (NCX1) is one of the main determinant in controlling Ca(2+) homeostasis. In cardiac hypertrophy and heart failure NCX1 expression and activity have been reported to be altered. It has been shown that chronic bacterial infections (sepsis, endocarditis, and myocarditis) can promote cardiac hypertrophy. Bacterial stressors, such as the Gram-negative endotoxin lipopolysaccharide (LPS), can directly or indirectly affect intracellular Ca(2+) homeostasis in the heart and induce the development of cardiac hypertrophy. The present study aimed at evaluating the potential link between the signal pathways activated in LPS-exposed myocytes and NCX1. In the whole rat heart, LPS perfusion induced an early hypertrophy response during which NCX1 expression significantly increased. Notably, all these changes were completely prevented by the NCX inhibitor SN-6. We further dissect the role of NCX1 in the LPS-induced hypertrophic response in an in vitro cardiac model based on two H9c2 cardiomyoblast clones, namely H9c2-WT (lacking endogenous NCX1 expression) and H9c2-NCX1 (stably transfected with a functional NCX1). H9c2-NCX1 were more susceptible than H9c2-WT to develop a hypertrophic phenotype, and they displayed a significant increase in NCX1 expression and function after LPS treatment. SN-6 completely counteracted both hypertrophic response and exchanger alterations induced by LPS in H9c2-NCX1 cells, but it had no effects on H9c2-WT. Collectively, our results suggest that NCX1 plays a critical role in promoting myocardial hypertrophy triggered by LPS. PMID:25445045

  6. Effects of endotoxin on mammary secretion of lactating cows. [Escherichia coli

    SciTech Connect

    Lengemann, F.W.; Pitzrick, M.

    1986-05-01

    The objectives were to describe the magnitude and time course of changes in milk pH, Na, K, lactose, and somatic cells and to determine if paracellular pathways were altered after infusion of Escherichia coli endotoxin (serotype 0128:AB12) to produce inflammation in one-half of the udder of the goat. Intramammary infusion of endotoxin increased pH, number of somatic cells, and Na and decreased K and lactose in milk. Sodium and number of somatic cells were increased by as little as .1..mu..g of endotoxin; .25 ..mu..g produced changes in most of the other parameters; maximal effect was elicited by 1..mu..g of endotoxin. The gland response peaked from 5 to 7 h after infusion of endotoxin with an increase in milk cellularity as the only significant effect noted in the control gland. Infusion of (/sup 14/C)lactose into the gland and (/sup 99m/Tc)albumin into the blood demonstrated that large molecules were more able to cross into and out of udder halves after endotoxin treatment. It is suggested that ion interchange rather than bulk flow across paracellular paths is responsible for changes. In addition, endotoxin appeared to reduce lactose secretion and synthesis.

  7. Airway administration of Escherichia coli endotoxin to mice induces glucocorticosteroid-resistant bronchoconstriction and vasopermeation.

    PubMed

    Lefort, J; Motreff, L; Vargaftig, B B

    2001-03-01

    The effects of the administration of Escherichia coli endotoxin (lipopolysaccharide, LPS) into the airways of C57Bl/6 mice were studied. Neutrophil sequestration in the lungs and their enrichment, together with tumor necrosis factor (TNF)-alpha, in bronchoalveolar lavage fluid (BALF) were associated with bronchoconstriction and bronchopulmonary hyperreactivity (BHR) to methacholine and alveolocapillary dysfunction. Granulocyte depletion by the myelotoxic drug vinblastine failed to modify TNF-alpha production and prevented LPS-induced neutrophil recruitment to lungs and BALF, bronchoconstriction, and BHR. Neutrophils were again sequestered in the lungs when LPS was administered 4 to 5 d after vinblastine, whereas inhibition of their passage to BALF persisted. Under those conditions, bronchoconstriction and BHR by LPS also recovered, showing that these functional effects are independent from BALF neutrophil enrichment but require lung sequestration. Administration of granulocyte colony-stimulating factor after vinblastine counteracted its effects and allowed the recovery of lung neutrophil sequestration by LPS and a partial recovery of bronchoconstriction under conditions where neutrophils still failed to migrate to BALF. Dexamethasone (the phosphate salt and its free base) suppressed LPS-induced TNF-alpha generation in BALF and its neutrophil enrichment, whereas neutrophil lung sequestration, bronchoconstriction, BHR, and alveolocapillary dysfunction were marginally reduced and only so at low doses of dexamethasone, higher doses being inactive or aggravating. In situ neutrophil activation could account for LPS-induced bronchoconstriction and BHR, both of which are refractory to steroids and appear to be mediated by unrelated mechanisms, which may be relevant for acute respiratory distress syndrome, a condition for which LPS administration is used as a model. PMID:11245635

  8. Endotoxin of Escherichia coli and permeability of the mammary glands of goats

    SciTech Connect

    Lengemann, F.W.; Pitzrick, M.

    1987-01-01

    Serial collections of milk were used to determine where in the mammary gland endotoxin of Escherichia coli was effective in altering the transfer of selected milk components into blood and blood components into milk. Lactating goats had half the gland infused with 1 ..mu..g of endotoxin and the other half served as a control. Sodium-24 and /sup 42/K or (/sup 14/C) lactose were included with /sup 141/Ce in the infusate in some experiments, whereas in others /sup 99m/Tc-labelled albumin or /sup 24/Na and /sup 42/K were given intravenously 2 h after the endotoxin infusion. Milk was collected 3 h after endotoxin infusion. Endotoxin increased the loss of /sup 24/Na, /sup 42/K, and (/sup 14/C) lactose from the mammary gland and increased the transfer of /sup 24/Na and /sup 99m/Tc-albumin into the gland. The transfer in of /sup 42/K was reduced compared with control halves. Movement of stable Na and K was in accord with the movement of the /sup 24/Na and /sup 42/K. Endotoxin was effective in all parts of the gland but particularly from the mid-portion upward to the alveoli. For the control halves there was evidence that some /sup 24/Na and /sup 42/K crossed the ductal or cisternal epithelium into blood outside of the alveoli, whereas only /sup 42/K provided evidence for transfer from blood to milk in these same regions. There was no demonstrable transfer of lactose and albumin in regions other than the alveoli.

  9. Exposure of periodontal ligament progenitor cells to lipopolysaccharide from Escherichia coli changes osteoblast differentiation pattern

    PubMed Central

    ALBIERO, Mayra Laino; AMORIM, Bruna Rabelo; MARTINS, Luciane; CASATI, Márcio Zaffalon; SALLUM, Enilson Antonio; NOCITI, Francisco Humberto; SILVÉRIO, Karina Gonzales

    2015-01-01

    Periodontal ligament mesenchymal stem cells (PDLMSCs) are an important alternative source of adult stem cells and may be applied for periodontal tissue regeneration, neuroregenerative medicine, and heart valve tissue engineering. However, little is known about the impact of bacterial toxins on the biological properties of PDLSMSCs, including self-renewal, differentiation, and synthesis of extracellular matrix. Objective : This study investigated whether proliferation, expression of pro-inflammatory cytokines, and osteogenic differentiation of CD105-enriched PDL progenitor cell populations (PDL-CD105+ cells) would be affected by exposure to bacterial lipopolysaccharide from Escherichia coli (EcLPS). Material and Methods : Toll-like receptor 4 (TLR4) expression was assessed in PDL-CD105+ cells by the immunostaining technique and confirmed using Western blotting assay. Afterwards, these cells were exposed to EcLPS, and the following assays were carried out: (i) cell viability using MTS; (ii) expression of the interleukin-1 beta (IL-1?), interleukin-6 (IL-6), interleukin-8 (IL-8), and tumor necrosis factor alpha (TNF-?) genes; (iii) osteoblast differentiation assessed by mineralization in vitro, and by mRNA levels of run-related transcription factor-2 (RUNX2), alkaline phosphatase (ALP) and osteocalcin (OCN) determined by quantitative PCR. Results : PDL-CD105+ cells were identified as positive for TLR4. EcLPS did not affect cell viability, but induced a significant increase of transcripts for IL-6 and IL-8. Under osteogenic condition, PDL-CD105+ cells exposed to EcLPS presented an increase of mineralized matrix deposition and higher RUNX2 and ALP mRNA levels when compared to the control group. Conclusions : These results provide evidence that CD105-enriched PDL progenitor cells are able to adapt to continuous Escherichia coli endotoxin challenge, leading to an upregulation of osteogenic activities. PMID:26018305

  10. Oral administration of Saccharomyces cerevisiae boulardii reduces Escherichia coli endotoxin associated mortality in weaned pigs

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The effects of active dry yeast, Saccharomyces cerevisiae boulardii (Scb), on the immune/neuroendocrine response and subsequent mortality to E. coli lipopolysaccharide (LPS) administration were evaluated in newly weaned pigs (26.1 + or - 3.4 d of age). Barrows were assigned to 1 of 2 treatment group...

  11. Underlying mechanisms involved in the decrease of milk secretion during Escherichia coli endotoxin induced mastitis in lactating mice

    PubMed Central

    2013-01-01

    Mastitis, the inflammation of mammary glands resulting from bacterial infection, disrupts milk production in lactating mammary glands. In this study, we injected lipopolysaccharide (LPS), one of the endotoxins from Escherichia coli into mouse mammary glands to disrupt milk production, and we investigated the influence of LPS on nutrient uptake, synthesis, and secretion processes for milk component production in alveolar epithelial cells (AEC). The expression of genes relevant to the three-staged milk component production process (nutrient uptake, synthesis, and secretion of milk components) were down-regulated within 12 h after LPS injection in AEC. The internalization of glucose transporter 1 (GLUT-1) from the basolateral membrane to the cytoplasm occurred in accordance with the down-regulation of gene expression 3 h after LPS injection. The abnormal localization of adipophilin and beta-casein was also observed in the LPS-injected mammary glands. SLC7A1, an amino acid transporter, was up-regulated 3 and 6 h after LPS injection. Furthermore, the inactivation of signal transducer and activator of transcription 5 (STAT5) and the activation of STAT3 and nuclear factor-kappa B (NFkappaB) occurred 3 h after LPS injection. These results indicate that the nutrient uptake, synthesis, and secretion of milk components in AEC are rapidly shut down in the lactating mammary glands after LPS injection. PMID:24308795

  12. The influence of sanitizers on the lipopolysaccharide composition of Escherichia coli O111.

    PubMed

    Venter, P; Abraham, M; Lues, J F R; Ivanov, I

    2006-10-01

    This study focused on the influence of typical sanitizers on the composition of the lipopolysaccharides (LPS) produced by the verocytotoxin-producing (VTEC) Escherichia coli O111. We also aimed to cast light on the applicability of O-antigen-based serotyping and endotoxin based Limulus Amebocyte Lysate (LAL) assays applied in the food industry for the identification and quantification of Gram-negative bacteria. E. coli O111 was propagated in the presence of three typical commercially applied sanitizing solutions that included a Clean in Place (CIP) chlorinated sanitizer (bacteriocidal), heavy-duty alkaline sanitizer (bacteriocidal) and a phenolic hand wash solution (bacteriostatic). After the required growth phase was reached the LPS from both the intact cells and debris was extracted and methanolysed followed by trifluoroacetylation. Subsequently GC-MS analysis and the chromogenic LAL assay were applied to assess both the ultra-structure and the toxicity of the extracted LPS. The viability and debris formation during growth was also evaluated to verify the bacteriocidial and static effect of the applied sanitizers as well as to assess its relationship with LPS formation. The total LPS produced was quantified at 1.3 x 10(6) [KDO] x OD(620 nm)(-1) for the control samples, 6.5 x 10(3) [KDO] x OD(620 nm)(-1) for E. coli grown in the presence of CIP chlorinated sanitizer and 2.1 x 10(5) and 2.85 x 10(6) [KDO] x OD(620 nm)(-1) for the organisms grown in the presence of heavy-duty alkaline sanitizer and phenolic hand wash solution respectively (KDO = 2-keto-3-deoxy-octulosonic acid). A negative correlation (gamma(2)= -0.880) between the [KDO] and Delta viability was evident and indicated that E. coli O111 responds to factors that hinder viability by producing more LPS in its outer membrane. Subsequent assessment of the LPS ultra-structure revealed a definite change in both the total assessed saccharide and lipid fractions. The cumulative change of the LPS in response to the sanitizers further appeared to influence the toxicity of the LPS as the latter change could not be related to an individual compound within any of the assessed fractions. This emphasised the fact that the quantity of LPS obtained from E. coli O111 in this study, did not seem to determine the toxicity of the organism. From the results we further propose a coefficient that could be applied to describe the response of E. coli O111 LPS to sanitizers and caution against the application of serotyping (based on the O-antigen) and the LAL assay to quantify and identify E. coli O111 obtained from food strata where the possibility of sanitizer contamination exists. PMID:16859796

  13. The effects of ACTH, prednisolone and Escherichia coli endotoxin on some clinical haematological and blood biochemical parameters in dwarf goats.

    PubMed

    van Miert, A S; van Duin, C T; Wensing, T

    1986-07-01

    ACTH (microgram kg-1 i.v.) and prednisolone (1 microgram-1 i.v.) caused a moderate but statistically significant inhibition of rumen contractions, whereas no effects on heart rate and body temperature were observed. Both hormones induced hyperglycaemia and leucocytosis, characterised by moderate lymphopenia and a profound increase in the number of circulating neutrophils. A significant decrease in plasma iron and increase in plasma zinc concentrations were observed. After 3 daily i.m. injections of ACTH (10 micrograms-1 day-1) decreases were seen in both serum Alkaline phosphatase (ALP) activity and plasma trace metal concentrations; heart rate was significantly higher. Intraveneous injection of E. coli endotoxin (0.1 microgram kg-1) caused shivering, fever, inhibition of rumen contractions, changes in heart rate, lymphopenia, neutropenia followed by neutrophilic leucocytosis, hypoferraemia, hypozincaemia, hypoglycaemia and a decline in serum ALP activity. ACTH, given i.m. for 3 days, reduced the febrile responses to E. coli endotoxin, modified the changes in heart rate, intensified the inhibition of rumen contractions, and induced a more marked decrease in the number of circulating neutrophils. ACTH pretreatment did not affect the endotoxin-induced decrease in blood glucose concentrations nor the drop in plasma zinc and iron values. These results suggest that glucocorticosteroids are not primarily involved in the fall in plasma iron and zinc concentrations during E. coli endotoxin-induced fever, the effects of endotoxin released glucocorticosteroids on white blood cells and blood glucose are masked by some other effect(s) of endotoxin, and in dwarf goats, ACTH has antipyretic properties without influencing normal body temperature. This effect is probably not dependent on adrenal cortical activity. PMID:3018991

  14. GENE EXPRESSION PROFILING OF BOVINE MACROPHAGES IN RESPONSE TO ESCHERICHIA COLI O157:H7 LIPOPOLYSACCHARIDE

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The aim of this study was to identify changes in bovine macrophage gene expression in response to treatment with Escherichia coli 0157:H7 lipopolysaccharide (LPS), utilizing a human gene microarray. Bovine cDNA from control and LPS-treated primary macrophages hybridized to greater than 5,644 (79.8%)...

  15. The Structural Basis for Lipid and Endotoxin Binding in RP105-MD-1, and Consequences for Regulation of Host Lipopolysaccharide Sensitivity.

    PubMed

    Ortiz-Suarez, Maite L; Bond, Peter J

    2016-01-01

    MD-1 is a member of the MD-2-related lipid-recognition (ML) family, and associates with RP105, a cell-surface protein that resembles Toll-like receptor 4 (TLR4). The RP105?MD-1 complex has been proposed to play a role in fine-tuning the innate immune response to endotoxin such as bacterial lipopolysaccharide (LPS) via TLR4?MD-2, but controversy surrounds its mechanism. We have used atomically detailed simulations to reveal the structural basis for ligand binding and consequent functional dynamics of MD-1 and the RP105 complex. We rationalize reports of endogenous phospholipid binding, by showing that they prevent collapse of the malleable MD-1 fold, before refining crystallographic models and uncovering likely binding modes for LPS analogs. Subsequent binding affinity calculations reveal that endotoxin specificity arises from the entropic cost of expanding the MD-1 cavity to accommodate bulky lipid tails, and support the role of MD-1 as a "sink" that sequesters endotoxin from TLR4 and stabilizes RP105/TLR4 interactions. PMID:26671709

  16. In vivo effects of the antiglucocorticoid RU 486 on glucocorticoid and cytokine responses to Escherichia coli endotoxin.

    PubMed Central

    Hawes, A S; Rock, C S; Keogh, C V; Lowry, S F; Calvano, S E

    1992-01-01

    The endogenous adrenocortical response to sepsis is critical for host survival. The in vivo interactions among the endogenous glucocorticoid response, the induction of cytokines, and host survival during endotoxemia were explored in this study by use of the glucocorticoid receptor antagonist RU 486. Male Lewis rats underwent sterile insertion of a right jugular venous catheter. After a 72-h recovery period, animals received a 50% lethal dose of Escherichia coli endotoxin (2.5 mg/kg) via the catheter after pretreatment for 30 min prior to lipopolysaccharide (LPS) treatment with (i) vehicle alone intravenously (i.v.) (-corticosterone [-Cort]/-RU 486/+LPS) (n = 10), (ii) the antiglucocorticoid RU 486 (10 mg/kg) i.v. (-Cort/+RU 486/+LPS) (n = 11), or (iii) RU 486 (10 mg/kg) i.v. in animals that had undergone subcutaneous implantation of a corticosterone pellet at the time of catheter insertion (+Cort/+RU 486/+LPS) (n = 10). Except in animals receiving corticosterone pretreatment, baseline plasma corticosterone levels were low in all groups. Plasma corticosterone levels increased significantly (P less than 0.001) above the baseline following LPS administration. Animals in the -Cort/+RU 486/+LPS-treated group exhibited significantly increased mortality (P less than 0.001), with only 9% of the animals surviving at 72 h, as well as significantly increased plasma interleukin-6 levels, compared with animals receiving the vehicle alone (-Cort/-RU 486/+LPS), which showed 50% mortality. Pretreatment with corticosterone and RU 486 (+Cort/+RU 486/+LPS) significantly (P less than 0.001) reversed the mortality observed with RU 486 pretreatment alone (-Cort/+RU 486/+LPS), with 70% of the animals surviving at 72 h, and significantly attenuated the peak plasma tumor necrosis factor and interleukin-6 responses to LPS, compared with those in the animals treated with vehicle alone. These data demonstrate that the blockade of glucocorticoid binding by RU 486 increases LPS-induced mortality. The reversal of this effect by the induction of hypercorticosteronemia prior to RU 486 and LPS exposure (+Cort/+RU 486/+LPS) improves survival and is further associated with significant attenuation of cytokine production. Therefore, these data suggest that the protective effect of the endogenous glucocorticoid response to acute endotoxemia may result from the down-regulation of a potentially lethal cytokine response. PMID:1612734

  17. Cloning and characterization of the Escherichia coli Heptosyltransferase III: Exploring substrate specificity in lipopolysaccharide core biosynthesis.

    PubMed

    Mudapaka, Jagadesh; Taylor, Erika Anne

    2015-06-01

    Bacterial lipopolysaccharide (LPS) molecules are an important cell surface component that enables adhesion to surfaces and cell motility, amongst other functions. In Escherichia coli, there are multiple Heptosyltransferase enzymes involved in the biosynthesis of the core region of LPS. Here we describe the first ever cloning, expression, purification and characterization of Heptosyltransferase III (HepIII) from E. coli, which catalyzes the addition of an L-glycero-D-manno-heptose (Hep) residue to the growing LPS core via an ?(1?7) bond. Inspired by results from our lab on the E. coli HepI, we assessed the catalytic efficiency with phospho-Hep2-Kdo2-Lipid A (PH2K2LA) and two deacylated analogues. PMID:25957775

  18. Morphological damage induced by Escherichia coli lipopolysaccharide in cultured hepatocytes: localization and binding properties.

    PubMed Central

    Pagani, R.; Portolés, M. T.; Díaz-Laviada, I.; Municio, A. M.

    1988-01-01

    Lipopolysaccharides (LPS) from Gram-negative bacteria are considered to be the responsible agents for the induction of endotoxic shock, affecting the liver as a target organ. In this study, the cell morphology and some biochemical properties of 24 h-culture-hepatocyte monolayers treated with Escherichia coli 0111:B4 lipopolysaccharide, were observed. Cell morphology was observed by scanning electron microscopy and immunofluorescence methods. LPS interaction induced an increase in rounded cells with diminished adhesion capacity. As biochemical parameters, albumin synthesis and 2-deoxyglucose uptake were measured. LPS decreased the hexose uptake in a dose-dependent manner. Binding of (14C)LPS to cultured hepatocytes showed that LPS binds to non-specific constituents of the membrane bilayer. Images Fig. 1 Fig. 2 Fig. 3 Fig. 7 PMID:3052562

  19. Trapped lipopolysaccharide and LptD intermediates reveal lipopolysaccharide translocation steps across the Escherichia coli outer membrane

    PubMed Central

    Li, Xuejun; Gu, Yinghong; Dong, Haohao; Wang, Wenjian; Dong, Changjiang

    2015-01-01

    Lipopolysaccharide (LPS) is a main component of the outer membrane of Gram-negative bacteria, which is essential for the vitality of most Gram-negative bacteria and plays a critical role for drug resistance. LptD/E complex forms a N-terminal LPS transport slide, a hydrophobic intramembrane hole and the hydrophilic channel of the barrel, for LPS transport, lipid A insertion and core oligosaccharide and O-antigen polysaccharide translocation, respectively. However, there is no direct evidence to confirm that LptD/E transports LPS from the periplasm to the external leaflet of the outer membrane. By replacing LptD residues with an unnatural amino acid p-benzoyl-L-phenyalanine (pBPA) and UV-photo-cross-linking in E.coli, the translocon and LPS intermediates were obtained at the N-terminal domain, the intramembrane hole, the lumenal gate, the lumen of LptD channel, and the extracellular loop 1 and 4, providing the first direct evidence and “snapshots” to reveal LPS translocation steps across the outer membrane. PMID:26149544

  20. The presence of endotoxin in powdered infant formula milk and the influence of endotoxin and Enterobacter sakazakii on bacterial translocation in the infant rat.

    PubMed

    Townsend, Stacy; Caubilla Barron, Juncal; Loc-Carrillo, Catherine; Forsythe, Stephen

    2007-02-01

    Lipopolysaccharide (LPS) is a heat stable endotoxin that persists during the processing of powdered infant formula milk (IFM). Upon ingestion it may increase the permeability of the neonatal intestinal epithelium and consequently bacterial translocation from the gut. To determine the level of endotoxin present in IFM, 75 samples were collected from seven countries (representing 31 brands) and analysed for endotoxin using the kinetic colorimetric Limulus amoebocyte lysate (LAL) assay. The endotoxin levels ranged from 40 to 5.5 x 10(4) endotoxin units (EU) per gram and did not correlate with the number of viable bacteria. The neonate rat model was used to address the risk of endotoxin-induced bacterial translocation from the gut. Purified Escherichia coli LPS was administered to rat pups followed by inoculation with Enterobacter sakazakii ATCC 12868. Bacteria were isolated from the mesentery, spleen, blood and cerebral spinal fluid (CSF) of endotoxin-treated rats due to enhanced gut and blood brain barrier penetration. Histological analysis of the colon showed marked distension of the mucosal and muscular layers. It is plausible that the risk of neonatal bacteraemia and endotoxemia, especially in neonates with immature innate immune systems, may be raised due to ingestion of IFM with high endotoxin levels. PMID:16943096

  1. Enhanced host immune recognition of E.coli causing mastitis in CD-14 transgenic mice.

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Escherchia coli causes mastitis, an economically significant disease in dairy animals. E. coli endotoxin (lipopolysaccharide, LPS) when bound by host membrane proteins such as CD-14, causes release of pro-inflammatory cytokines recruiting neutrophils as a early innate immune response. Excessive pr...

  2. Lipopolysaccharide biosynthesis without the lipids: recognition promiscuity of Escherichia coli heptosyltransferase I.

    PubMed

    Czyzyk, Daniel J; Liu, Cassie; Taylor, Erika A

    2011-12-13

    Heptosyltransferase I (HepI) is responsible for the transfer of l-glycero-d-manno-heptose to a 3-deoxy-?-D-oct-2-ulopyranosonic acid (Kdo) of the growing core region of lipopolysaccharide (LPS). The catalytic efficiency of HepI with the fully deacylated analogue of Escherichia coli HepI LipidA is 12-fold greater than with the fully acylated substrate, with a k(cat)/K(m) of 2.7 × 10(6) M(-1) s(-1), compared to a value of 2.2 × 10(5) M(-1) s(-1) for the Kdo(2)-LipidA substrate. Not only is this is the first demonstration that an LPS biosynthetic enzyme is catalytically enhanced by the absence of lipids, this result has significant implications for downstream enzymes that are now thought to utilize deacylated substrates. PMID:22059588

  3. Lipopolysaccharide Biosynthesis without the Lipids: Recognition Promiscuity of Escherichia coli Heptosyltransferase I

    PubMed Central

    Czyzyk, Daniel J.; Liu, Cassie; Taylor, Erika A.

    2011-01-01

    Heptosyltransferase I (HepI) is responsible for the transfer of L-glycero-D-manno-heptose to a 3-deoxy-?-D-oct-2-ulopyranosonic acid (Kdo) of the growing core region of lipopolysaccharide (LPS). The catalytic efficiency of HepI with the fully deacylated analogue of Escherichia coli HepI LipidA is 12-fold greater than with the fully acylated substrate, with a kcat/Km of 2.7 × 106 M?1 s?1, compared to a value of 2.2 × 105 M?1 s?1 for the Kdo2-LipidA substrate. Not only is this is the first demonstration that an LPS biosynthetic enzyme is catalytically enhanced by the absence of lipids, this result has significant implications for downstream enzymes that are now thought to utilize deacylated substrates. PMID:22059588

  4. Bladder instillation of Escherichia coli lipopolysaccharide alters the muscle contractions in rat urinary bladder via a protein kinase C-related pathway

    SciTech Connect

    Weng, T.I.; Chen, W.J.; Liu, S.H. . E-mail: shliu@ha.mc.ntu.edu.tw

    2005-10-15

    Uropathogenic Escherichia coli is a common cause of urinary tract infection. We determined the effects of intravesical instillation of E. coli lipopolysaccharide (LPS, endotoxin) on muscle contractions, protein kinase C (PKC) translocation, and inducible nitric oxide synthase (iNOS) expression in rat urinary bladder. The contractions of the isolated rat detrusor muscle evoked by electrical field stimulations were measured short-term (1 h) or long-term (24 h) after intravesical instillation of LPS. One hour after LPS intravesical instillation, bladder PKC-{alpha} translocation from cytosolic fraction to membrane fraction and endothelial (e)NOS protein was elevated, and detrusor muscle contractions were significantly increased. PKC inhibitors chelerythrine and Ro32-0432 inhibited this LPS-enhanced contractile response. Application of PKC activator {beta}-phorbol-12,13-dibutyrate enhanced the muscle contractions. Three hours after intravesical instillation of LPS, iNOS mRNA was detected in the bladder. Immunoblotting study also demonstrated that the induction of iNOS proteins is detected in bladder in which LPS was instilled. 24 h after intravesical instillation of LPS, PKC-{alpha} translocation was impaired in the bladder; LPS did not affect PKC-{delta} translocation. Muscle contractions were also decreased 24 h after LPS intravesical instillation. Aminoguanidine, a selective iNOS inhibitor, blocked the decrease in PKC-{alpha} translocation and detrusor contractions induced by LPS. These results indicate that there are different mechanisms involved in the alteration of urinary bladder contractions after short-term and long-term treatment of LPS; an iNOS-regulated PKC signaling may participate in causing the inhibition of muscle contractions in urinary bladder induced by long-term LPS treatment.

  5. Oral administration of Saccharomyces cerevisiae boulardii reduces mortality associated with immune and cortisol responses to Escherichia coli endotoxin in weaned pigs

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The effects of active dry yeast, Saccharomyces cerevisiae boulardii (Scb), on the immune/cortisol response and subsequent mortality to E. coli lipopolysaccharide (LPS) administration were evaluated in newly weaned piglets (26.1 +/- 3.4 d of age). Barrows were assigned to 1 of 2 treatment groups, wit...

  6. Role of Cell Surface Lipopolysaccharides in Escherichia coli K12 adhesion and transport.

    PubMed

    Walker, Sharon L; Redman, Jeremy A; Elimelech, Menachem

    2004-08-31

    The influence of bacterial surface lipopolysaccharides (LPS) on cell transport and adhesion has been examined by use of three mutants of Escherichia coli K12 with well-characterized LPS of different lengths and molecular composition. Two experimental techniques, a packed-bed column and a radial stagnation point flow system, were employed to investigate bacterial adhesion kinetics onto quartz surfaces over a wide range of solution ionic strengths. Although the two systems capture distinct deposition (adhesion) mechanisms because of their different hydrodynamics, similar deposition kinetics trends were observed for each bacterial strain. Bacterial deposition rates were directly related to the electrostatic double layer interaction between the bacteria and quartz surfaces, in qualitative agreement with classic Derjaguin-Landau-Verwey-Overbeek (DLVO) theory. However, DLVO theory does not fully explain the deposition behavior for the bacterial strain with the lengthy, uncharged O-antigen portion of the LPS. Neither the length nor the charge characteristics of the LPS molecule directly correlated to deposition kinetics, suggesting a complex combination of cell surface charge heterogeneity and LPS composition controls the bacterial adhesive characteristics. It is further suggested that bacterial deposition behavior is determined by the combined influence of DLVO interactions, LPS-associated chemical interactions, and the hydrodynamics of the deposition system. PMID:15323526

  7. Biologic properties of nontoxic derivatives of a lipopolysaccharide from Escherichia coli K235.

    PubMed

    McIntire, F C; Hargie, M P; Schenck, J R; Finley, R A; Sievert, H W; Rietschel, E T; Rosenstreich, D L

    1976-08-01

    Lipopolysaccharide (LPS)2 from Escherichia coli K235 was treated with o-phthalic anhydride to obtain a high degree of esterification of available hydroxyl groups, leaving a free carboxyl for each hydroxyl esterified (SPLPS). Although there was no demonstrable loss of fatty acids, this conversion of LPS to a polyanionic molecule altered dramatically the spectrum of biologic properties, most of which are normally attributed to the lipid A (LA) moiety. Mitogenicity for mouse B cells was decreased several hundred-fold; reaction with antibodies to LPS was abolished; pyrogenicity and toxicity were decreased by factors of 10(5) and 10(4); the ability to induce the Shwartzman reaction in rabbits was decreased 500-fold, and the ability to stimulate production of interferon in mice was decreased by more than 2 x 10(3). However, despite the loss of these properties, SPLPS retained the ability to act as an immunologic adjuvant. The nature of the anionic group is important, e.g., sodium succinyl-LPS (SuLPS) is 10-fold more pyrogenic and toxic than sodium phthalyl-LPS (SPLPS). Data on another LPS derivative, from which ester-linked fatty acid residues were removed before phthalylation, suggest that the ester-linked fatty acid groups in the lipid A moeity of SPLPS may not be necessary for its immunologic adjuvant effect. PMID:781135

  8. Removal of Endotoxins from Bacteriophage Preparations by Extraction with Organic Solvents

    PubMed Central

    Szermer-Olearnik, Bo?ena; Boraty?ski, Janusz

    2015-01-01

    Lipopolysaccharide (LPS, endotoxin, pyrogen) constitutes a very troubling contaminant of crude phage lysates produced in Gram-negative bacteria. Toxicity of LPS depends on the strong innate immunity response including the cytokines. Therefore, its removal is important for bacteriophage applications. In this paper, we present a procedure for extractive removal of endotoxin from bacteriophage preparations with water immiscible solvents (1-octanol or 1-butanol). During extraction most of the phage lytic activity is retained in the aqueous phase, while endotoxin accumulates in the organic solvent. The levels of endotoxin (expressed as endotoxin units, EU) in the aqueous bacteriophage-containing fraction determined by limulus amebocyte lysate or EndoLISA assay were exceptionally low. While the initial endotoxin levels in the crude phage lysates ranged between 103 and 105 EU/ml the average level after organic extraction remaining in the aqueous fraction was 5.3 EU/ml. These values when related to phage titers decreased from 103-105 EU/109 PFU (plaque forming units) down to an average of 2.8 EU/109 PFU. The purification procedure is scalable, efficient and applicable to all the bacteriophages tested: T4, HAP1 (E. coli) and F8 (P. aeruginosa). PMID:25811193

  9. Metabolic and Hematological Consequences of Dietary Deoxynivalenol Interacting with Systemic Escherichia coli Lipopolysaccharide

    PubMed Central

    Bannert, Erik; Tesch, Tanja; Kluess, Jeannette; Frahm, Jana; Kersten, Susanne; Kahlert, Stefan; Renner, Lydia; Rothkötter, Hermann-Josef; Dänicke, Sven

    2015-01-01

    Previous studies have shown that chronic oral deoxynivalenol (DON) exposure modulated Escherichia coli lipopolysaccharide (LPS)-induced systemic inflammation, whereby the liver was suspected to play an important role. Thus, a total of 41 barrows was fed one of two maize-based diets, either a DON-diet (4.59 mg DON/kg feed, n = 19) or a control diet (CON, n = 22). Pigs were equipped with indwelling catheters for pre- or post-hepatic (portal vs. jugular catheter) infusion of either control (0.9% NaCl) or LPS (7.5 µg/kg BW) for 1h and frequent blood sampling. This design yielded six groups: CON_CONjugular-CONportal, CON_CONjugular-LPSportal, CON_LPSjugular-CONportal, DON_CONjugular-CONportal, DON_CONjugular-LPSportal and DON_LPSjugular-CONportal. Blood samples were analyzed for blood gases, electrolytes, glucose, pH, lactate and red hemogram. The red hemogram and electrolytes were not affected by DON and LPS. DON-feeding solely decreased portal glucose uptake (p < 0.05). LPS-decreased partial oxygen pressure (pO2) overall (p < 0.05), but reduced pCO2 only in arterial blood, and DON had no effect on either. Irrespective of catheter localization, LPS decreased pH and base-excess (p < 0.01), but increased lactate and anion-gap (p < 0.01), indicating an emerging lactic acidosis. Lactic acidosis was more pronounced in the group DON_LPSjugular-CONportal than in CON-fed counterparts (p < 0.05). DON-feeding aggravated the porcine acid-base balance in response to a subsequent immunostimulus dependent on its exposure site (pre- or post-hepatic). PMID:26580654

  10. Metabolic and Hematological Consequences of Dietary Deoxynivalenol Interacting with Systemic Escherichia coli Lipopolysaccharide.

    PubMed

    Bannert, Erik; Tesch, Tanja; Kluess, Jeannette; Frahm, Jana; Kersten, Susanne; Kahlert, Stefan; Renner, Lydia; Rothkötter, Hermann-Josef; Dänicke, Sven

    2015-01-01

    Previous studies have shown that chronic oral deoxynivalenol (DON) exposure modulated Escherichia coli lipopolysaccharide (LPS)-induced systemic inflammation, whereby the liver was suspected to play an important role. Thus, a total of 41 barrows was fed one of two maize-based diets, either a DON-diet (4.59 mg DON/kg feed, n = 19) or a control diet (CON, n = 22). Pigs were equipped with indwelling catheters for pre- or post-hepatic (portal vs. jugular catheter) infusion of either control (0.9% NaCl) or LPS (7.5 µg/kg BW) for 1h and frequent blood sampling. This design yielded six groups: CON_CONjugular?CONportal, CON_CONjugular?LPSportal, CON_LPSjugular?CONportal, DON_CONjugular?CONportal, DON_CONjugular?LPSportal and DON_LPSjugular?CONportal. Blood samples were analyzed for blood gases, electrolytes, glucose, pH, lactate and red hemogram. The red hemogram and electrolytes were not affected by DON and LPS. DON-feeding solely decreased portal glucose uptake (p < 0.05). LPS-decreased partial oxygen pressure (pO?) overall (p < 0.05), but reduced pCO? only in arterial blood, and DON had no effect on either. Irrespective of catheter localization, LPS decreased pH and base-excess (p < 0.01), but increased lactate and anion-gap (p < 0.01), indicating an emerging lactic acidosis. Lactic acidosis was more pronounced in the group DON_LPSjugular-CONportal than in CON-fed counterparts (p < 0.05). DON-feeding aggravated the porcine acid-base balance in response to a subsequent immunostimulus dependent on its exposure site (pre- or post-hepatic). PMID:26580654

  11. Resistance of MMP9 and TIMP1 to endotoxin tolerance.

    PubMed

    Muthukuru, Manoj; Cutler, Christopher W

    2015-07-01

    Inflammatory cytokines activate tissue collagenases such as matrix metalloproteinases (MMPs). MMPs are antagonized by tissue inhibitors of metalloproteinases (TIMPs) that attempt to regulate excessive collagenase activity during inflammatory conditions. During chronic inflammatory conditions, induction of endotoxin tolerance negatively regulates the cytokine response in an attempt to curtail excessive host tissue damage. However, little is known about how downregulation of inflammatory cytokines during endotoxin tolerance regulates MMP activities. In this study, human monocyte-derived macrophages were either sensitized or further challenged to induce tolerance with lipopolysaccharide (LPS) from Porphyromonas gingivalis (PgLPS) or Escherichia coli (EcLPS). Inflammatory cytokines, such as TNF-? and IL-1?, and levels of MMP9 and TIMP1 were analyzed by a combination of cytometric bead array, western blot/gelatin zymography and real-time RT-PCR. Functional blocking with anti-TLR4 but not with anti-TLR2 significantly downregulated TNF-? and IL-1?. However, MMP9 levels were not inhibited by toll-like receptor (TLR) blocking. Interestingly, endotoxin tolerance significantly upregulated TIMP1 relative to MMP9 and downmodulated MMP9 secretion and its enzymatic activity. These results suggest that regulatory mechanisms such as induction of endotoxin tolerance could inhibit MMP activities and could facilitate restoring host tissue homeostasis. PMID:25951835

  12. Naturally occurring hypothermia is more advantageous than fever in severe forms of lipopolysaccharide- and Escherichia coli-induced systemic inflammation

    PubMed Central

    Liu, Elaine; Lewis, Kevin; Al-Saffar, Hiba; Krall, Catherine M.; Singh, Anju; Kulchitsky, Vladimir A.; Corrigan, Joshua J.; Simons, Christopher T.; Petersen, Scott R.; Musteata, Florin M.; Bakshi, Chandra S.; Romanovsky, Andrej A.; Sellati, Timothy J.

    2012-01-01

    The natural switch from fever to hypothermia observed in the most severe cases of systemic inflammation is a phenomenon that continues to puzzle clinicians and scientists. The present study was the first to evaluate in direct experiments how the development of hypothermia vs. fever during severe forms of systemic inflammation impacts the pathophysiology of this malady and mortality rates in rats. Following administration of bacterial lipopolysaccharide (LPS; 5 or 18 mg/kg) or of a clinical Escherichia coli isolate (5 × 109 or 1 × 1010 CFU/kg), hypothermia developed in rats exposed to a mildly cool environment, but not in rats exposed to a warm environment; only fever was revealed in the warm environment. Development of hypothermia instead of fever suppressed endotoxemia in E. coli-infected rats, but not in LPS-injected rats. The infiltration of the lungs by neutrophils was similarly suppressed in E. coli-infected rats of the hypothermic group. These potentially beneficial effects came with costs, as hypothermia increased bacterial burden in the liver. Furthermore, the hypotensive responses to LPS or E. coli were exaggerated in rats of the hypothermic group. This exaggeration, however, occurred independently of changes in inflammatory cytokines and prostaglandins. Despite possible costs, development of hypothermia lessened abdominal organ dysfunction and reduced overall mortality rates in both the E. coli and LPS models. By demonstrating that naturally occurring hypothermia is more advantageous than fever in severe forms of aseptic (LPS-induced) or septic (E. coli-induced) systemic inflammation, this study provides new grounds for the management of this deadly condition. PMID:22513748

  13. ELEVATED MILK SOLUBLE CD 14 IN BOVINE MAMMARY GLANDS CHALLENGED WITH E. COLI LIPOPOLYSACCHARIDE

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The purpose of this study was to determine whether soluble CD 14 in milk were affected by the stage of lactation, the level of milk somatic cell count (SCC), the presence of bacteria or lipopolysaccharide (LPS)-induced inflammation. First, milk samples from 100 lactating cows (396 functional quarter...

  14. Changes of stress oxidative enzymes in rat mammary tissue, blood and milk after experimental mastitis induced by E. coli lipopolysaccharide

    PubMed Central

    Eslami, Hadi; Batavani, Rooz Ali; Asr?i-Rezaei, Siamak; Hobbenaghi, Rahim

    2015-01-01

    The present study investigated the effects of E. coli lipopolysaccharide (LPS) induced mastitis model in rat on the activity of antioxidant enzyme systems. To achieve this purpose, E. coli LPS were infused into the mammary gland of 12 rats 72 hr postpartum and compared with 12 rats in control group infused intramammary placebo sterile pyrogene – free, physiological saline. The antioxidant activities of the enzymes, superoxide dismutase, glutathione peroxidase, and catalase together with ??malondialdehyde (MDA) level were assayed in blood serum, milk and mammary tissue. Results obtained showed that, the antioxidant enzyme activities in milk, blood serum and mammary tissue were significantly decreased while the level of MDA, the indicator of lipid peroxidation were significantly increased following intramammary inoculation of LPS compared to the control animals. Histopathological examination also revealed the infiltration of inflammatory cells in mammary tissue and disruption of acinar structure and acinar lumina in mastitic rats. The results indicated that E. coli LPS-induced ?mastitis could alter antioxidant enzymes and increase lipid peroxidation. PMID:26261708

  15. ENDOTOXINS, ALGAE AND 'LIMULUS' AMOEBOCYTE LYSATE TEST IN DRINKING WATER

    EPA Science Inventory

    Field and laboratory studies were conducted to determine the distribution of algae and bacteria, and investigate sources of endotoxins (lipopolysaccharides) in drinking water. The field survey was performed on five drinking water systems located in Allegheny County, Pennsylvania ...

  16. IFIT2 is an effector protein of type I IFN-mediated amplification of lipopolysaccharide (LPS)-induced TNF-? secretion and LPS-induced endotoxin shock.

    PubMed

    Siegfried, Alexandra; Berchtold, Susanne; Manncke, Birgit; Deuschle, Eva; Reber, Julia; Ott, Thomas; Weber, Michaela; Kalinke, Ulrich; Hofer, Markus J; Hatesuer, Bastian; Schughart, Klaus; Gailus-Durner, Valérie; Fuchs, Helmut; Hrabe de Angelis, Martin; Weber, Friedemann; Hornef, Mathias W; Autenrieth, Ingo B; Bohn, Erwin

    2013-10-01

    Type I IFN signaling amplifies the secretion of LPS-induced proinflammatory cytokines such as TNF-? or IL-6 and might thus contribute to the high mortality associated with Gram-negative septic shock in humans. The underlying molecular mechanism, however, is ill defined. In this study, we report the generation of mice deficient in IFN-induced protein with tetratricopeptide repeats 2 (Ifit2) and demonstrate that Ifit2 is a critical signaling intermediate for LPS-induced septic shock. Ifit2 expression was significantly upregulated in response to LPS challenge in an IFN-? receptor- and IFN regulatory factor (Irf)9-dependent manner. Also, LPS induced secretion of IL-6 and TNF-? by bone marrow-derived macrophages (BMDMs) was significantly enhanced in the presence of Ifit2. In accordance, Ifit2-deficient mice exhibited significantly reduced serum levels of IL-6 and TNF-? and reduced mortality in an endotoxin shock model. Investigation of the underlying signal transduction events revealed that Ifit2 upregulates Irf3 phosphorylation. In the absence of Irf3, reduced Ifn-? mRNA expression and Ifit2 protein expression after LPS stimulation was found. Also, Tnf-? and Il-6 secretion but not Tnf-? and Il-6 mRNA expression levels were reduced. Thus, IFN-stimulated Ifit2 via enhanced Irf3 phosphorylation upregulates the secretion of proinflammatory cytokines. It thereby amplifies LPS-induced cytokine production and critically influences the outcome of endotoxin shock. PMID:24014876

  17. The structural characterization of the O-polysaccharide antigen in the lipopolysaccharide of Escherichia coli serotype O118 and its relationship to the O-antigens of Salmonella enterica O47 and Escherichia coli serotype O151

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Mild acid hydrolysis of the lipopolysaccharide produced by Escherichia coli O118:H16 (standard reference strain; NRCC 6613) contained an O-polysaccharide (O-PS) composed of D-galactose, 2-acetimidoylamino-2,6-dideoxy-L-galactose (L-FucNAm), 2-acetamido-2-deoxy-D-glucose, ribitol, and phosphate (1:1...

  18. Endotoxin induced uncoupling of the somatotrophic axis in nursery pigs

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Lipopolysaccharide (LPS) is an endotoxin known to stimulate the innate immune response and stress axis in pigs. However, little is known about the effects of LPS on pig somatotrophic responses. The objective of this study was to determine the effects of an endotoxin challenge on weaned pig serum con...

  19. Effect of endotoxin administration in pregnant camels

    PubMed Central

    AL-Dughaym, A.M.; Homeida, A.M.

    2010-01-01

    Intravenous administration of Escherichia coli endotoxin at a dose of 0.05 ?g/kg bodyweight to pregnant camels resulted in abortion. The injection of endotoxin caused significant increases in the plasma concentration of 13,14-dihydro-15-prostaglandin F2?, the metabolite of prostaglandin F2? (PG F2?) and cortisol and a significant decrease in the concentration of progesterone. It is suggested that endotoxin caused abortion in camels was a consequence of endotoxin induced PG F2? secretion resulting in luteal regression and decreased progesterone concentration. PMID:23961064

  20. Interleukin-1 decreases renal sodium reabsorption: possible mechanism of endotoxin-induced natriuresis

    SciTech Connect

    Caverzasio, J.; Rizzoli, R.; Dayer, J.M.; Bonjour, J.P.

    1987-05-01

    Administration of pyrogen or endotoxins such as Escherichia coli lipopolysaccharide can elicit a marked increase in urinary sodium excretion. This response occurs without any elevation in the filtered load of sodium and it does not appear to be prostaglandin mediated. The various effects produced by endotoxins appear to have interleukin-1 as a common mediator. In the present work, the authors have studied whether human recombinant interleukin-1..beta.. (hrIL-1) could affect the renal handling of sodium and thus, could be implicated in natriuretic response to pyrogens or endotoxins. They observed that hrIL-1 intravenously injected into conscious rats provokes a marked increase in sodium excretion. This natriuretic response was not associated with any increase in glomerular filtration rate (clearance of (/sup 3/H)inulin), nor was it accompanied by significant changes in the urinary excretion of potassium, calcium, or inorganic phosphate. The only concomitant alteration was a decrease in urinary pH. Pretreatment with indomethacin abolished the effect of hrIL-1 on urinary pH but did not modify the natriuretic response. In conclusion, hrIL-1 elicits a selective decrease in tubular sodium reabsorption, which does not appear to involve a change in prostaglandin synthesis. This observation strongly suggests that interleukin-1 could be a key mediator in endotoxin-induced natriuresis.

  1. The Lipopolysaccharide Export Pathway in Escherichia coli: Structure, Organization and Regulated Assembly of the Lpt Machinery

    PubMed Central

    Polissi, Alessandra; Sperandeo, Paola

    2014-01-01

    The bacterial outer membrane (OM) is a peculiar biological structure with a unique composition that contributes significantly to the fitness of Gram-negative bacteria in hostile environments. OM components are all synthesized in the cytosol and must, then, be transported efficiently across three compartments to the cell surface. Lipopolysaccharide (LPS) is a unique glycolipid that paves the outer leaflet of the OM. Transport of this complex molecule poses several problems to the cells due to its amphipatic nature. In this review, the multiprotein machinery devoted to LPS transport to the OM is discussed together with the challenges associated with this process and the solutions that cells have evolved to address the problem of LPS biogenesis. PMID:24549203

  2. Dose dependence of endotoxin-induced activation of the plasma contact system: an in vitro study.

    PubMed

    Roeise, O; Bouma, B N; Stadaas, J O; Aasen, A O

    1988-12-01

    The dose and time dependence of endotoxin-induced activation of the plasma contact system have been studied. Citrated pool plasma was incubated at 37 degrees C with endotoxin doses of 2.10(5), 2.10(6), 2.10(7), and 2.10(9) ng/l (lipopolysaccharide B, E. coli 026: B6, Difco Laboratories, Detroit, MI) for 24 hr. Samples for determination of components of the contact system were obtained prior to incubation and at 1, 2, 4, 6, 12, and 24 hr. Plasma kallikrein (KK) activity markedly increased at 12 hr in test plasma containing the highest dose of endotoxin (2.10(9) ng/l). Coincident with the elevated KK activity, reductions of both plasma prekallikrein (PKK) and functional kallikrein inhibition (KKI) were seen as assayed by chromogenic peptide substrate analyses. Also, functionally determined alpha 2-macroglobulin (alpha 2-M) and C1 inhibitor (C1INH) values were decreased, confirming the reduction of KKI values. Changes of Hageman factor (FXII), PKK, and high molecular weight kininogen (HMWK) values were also found at the same time point when assayed by immunochemical techniques. The same pattern of changes was seen in test plasma containing 2.10(7) and 2.10(6) ng/l of endotoxin. These changes, however, were less pronounced and not seen until 24 hr after beginning incubation. In control plasma and in plasma containing the lowest dose of endotoxin (2.10(5) ng/l), no changes were seen in any factors of the contact system. Our study shows that in vitro endotoxin-induced activation of the contact system is a slow process that is both time and dose dependent. PMID:2463883

  3. The potential of lipopolysaccharide as a real-time biomarker of bacterial contamination in marine bathing water.

    PubMed

    Sattar, Anas A; Jackson, Simon K; Bradley, Graham

    2014-03-01

    The use of total lipopolysaccharide (LPS) as a rapid biomarker for bacterial pollution was investigated at a bathing and surfing beach during the UK bathing season. The levels of faecal indicator bacteria Escherichia coli (E. coli), the Gram-positive enterococci, and organisms commonly associated with faecal material, such as total coliforms and Bacteroides, were culturally monitored over four months to include a period of heavy rainfall and concomitant pollution. Endotoxin measurement was performed using a kinetic Limulus Amebocyte Lysate (LAL) assay and found to correlate well with all indicators. Levels of LPS in excess of 50 Endotoxin Units (EU) mL(-1) were found to correlate with water that was unsuitable for bathing under the current European regulations. Increases in total LPS, mainly from Gram-negative indicator bacteria, are thus a potential real-time, qualitative method for testing bacterial quality of bathing waters. PMID:24642437

  4. Endotoxin removal by radio frequency gas plasma (glow discharge)

    NASA Astrophysics Data System (ADS)

    Poon, Angela

    2011-12-01

    Contaminants remaining on implantable medical devices, even following sterilization, include dangerous fever-causing residues of the outer lipopolysaccharide-rich membranes of Gram-negative bacteria such as the common gut microorganism E. coli. The conventional method for endotoxin removal is by Food & Drug Administration (FDA)-recommended dry-heat depyrogenation at 250°C for at least 45 minutes, an excessively time-consuming high-temperature technique not suitable for low-melting or heat-distortable biomaterials. This investigation evaluated the mechanism by which E. coli endotoxin contamination can be eliminated from surfaces during ambient temperature single 3-minute to cumulative 15-minute exposures to radio-frequency glow discharge (RFGD)-generated residual room air plasmas activated at 0.1-0.2 torr in a 35MHz electrodeless chamber. The main analytical technique for retained pyrogenic bio-activity was the Kinetic Chromogenic Limulus Amebocyte Lysate (LAL) Assay, sufficiently sensitive to document compliance with FDA-required Endotoxin Unit (EU) titers less than 20 EU per medical device by optical detection of enzymatic color development corresponding to < 0.5 EU/ml in sterile water extracts of each device. The main analytical technique for identification of chemical compositions, amounts, and changes during sequential reference Endotoxin additions and subsequent RFGD-treatment removals from infrared (IR)-transparent germanium (Ge) prisms was Multiple Attenuated Internal Reflection (MAIR) infrared spectroscopy sensitive to even monolayer amounts of retained bio-contaminant. KimaxRTM 60 mm x 15 mm and 50mm x 15mm laboratory glass dishes and germanium internal reflection prisms were inoculated with E. coli bacterial endotoxin water suspensions at increments of 0.005, 0.05, 0.5, and 5 EU, and characterized by MAIR-IR spectroscopy of the dried residues on the Ge prisms and LAL Assay of sterile water extracts from both glass and Ge specimens. The Ge prism MAIR-IR measurements were repeated after employing 3-minute RFGD treatments sequentially for more than 10 cycles to observe removal of deposited matter that correlated with diminished EU titers. The results showed that 5 cycles, for a total exposure time of 15 minutes to low-temperature gas plasma, was sufficient to reduce endotoxin titers to below 0.05 EU/ml, and correlated with concurrent reduction of major endotoxin reference standard absorption bands at 3391 cm-1, 2887 cm-1, 1646 cm -1 1342 cm-1, and 1103 cm-1 to less than 0.05 Absorbance Units. Band depletion varied from 15% to 40% per 3-minute cycle of RFGD exposure, based on peak-to-peak analyses. In some cases, 100% of all applied biomass was removed within 5 sequential 3-minute RFGD cycles. The lipid ester absorption band expected at 1725 cm-1 was not detectable until after the first RFGD cycle, suggesting an unmasking of the actual bacterial endotoxin membrane induced within the gas plasma environment. Future work must determine the applicability of this low-temperature, quick depyrogenation process to medical devices of more complicated geometry than the flat surfaces tested here.

  5. Endotoxin-free protein production--ClearColiTM A new Escherichia coli strain with a genetically modified lipopolysaccharide (LPS) molecule has been

    E-print Network

    Cai, Long

    are regularly used as the first-choice host for DNA cloning and protein production, including in FDA as research tools and protein production platforms for therapeutic proteins. Lucigen and Research Corporation

  6. Endotoxin-Binding Peptides Derived from Casein Glycomacropeptide Inhibit Lipopolysaccharide-Stimulated Inflammatory Responses via Blockade of NF-?B activation in macrophages

    PubMed Central

    Cheng, Xue; Gao, Dongxiao; Chen, Bin; Mao, Xueying

    2015-01-01

    Systemic low-grade inflammation and increased circulating lipopolysaccharide (LPS) contribute to metabolic dysfunction. The inhibitory effects and underlying molecular mechanisms of casein glycomacropeptide (GMP) hydrolysate on the inflammatory response of LPS-stimulated macrophages were investigated. Results showed that the inhibitory effect of GMP hydrolysates obtained with papain on nitric oxide (NO) production were obviously higher than that of GMP hydrolysates obtained with pepsin, alcalase and trypsin (p < 0.05), and the hydrolysate obtained with papain for 1 h hydrolysis (GHP) exhibited the highest inhibitory effect. Compared with native GMP, GHP markedly inhibited LPS-induced NO production in a dose-dependent manner with decreased mRNA level of inducible nitric oxide synthase (iNOS). GHP blocked toll-like receptor 4 (TLR4)/myeloid differentiation primary response 88 (MyD88)/nuclear factor-?B (NF-?B) signaling pathway activation, accompanied by downregulation of LPS-triggered significant upregulation of tumor necrosis factor (TNF)-? and interleukin (IL)-1? gene expression. Furthermore, GHP could neutralize LPS not only by direct binding to LPS, but also by inhibiting the engagement of LPS with the TLR4/MD2 complex, making it a potential LPS inhibitor. In conclusion, these findings suggest that GHP negatively regulates TLR4-mediated inflammatory response in LPS-stimulated RAW264.7 cells, and therefore may hold potential to ameliorate inflammation-related issues. PMID:25923657

  7. Structure and Functional Analysis of LptC, a Conserved Membrane Protein Involved in the Lipopolysaccharide Export Pathway in Escherichia coli*

    PubMed Central

    Tran, An X.; Dong, Changjiang; Whitfield, Chris

    2010-01-01

    LptC is a conserved bitopic inner membrane protein from Escherichia coli involved in the export of lipopolysaccharide from its site of synthesis in the cytoplasmic membrane to the outer membrane. LptC forms a complex with the ATP-binding cassette transporter, LptBFG, which is thought to facilitate the extraction of lipopolysaccharide from the inner membrane and release it into a translocation pathway that includes the putative periplasmic chaperone LptA. Cysteine modification experiments established that the catalytic domain of LptC is oriented toward the periplasm. The structure of the periplasmic domain is described at a resolution of 2.2-? from x-ray crystallographic data. The periplasmic domain of LptC consists of a twisted boat structure with two ?-sheets in apposition to each other. The ?-sheets contain seven and eight antiparallel ?-strands, respectively. This structure bears a high degree of resemblance to the crystal structure of LptA. Like LptA, LptC binds lipopolysaccharide in vitro. In vitro, LptA can displace lipopolysaccharide from LptC (but not vice versa), consistent with their locations and their proposed placement in a unidirectional export pathway. PMID:20720015

  8. A comparison of the endotoxin biosynthesis and protein oxidation pathways in the biogenesis of the outer membrane of Escherichia coli and Neisseria meningitidis

    PubMed Central

    Piek, Susannah; Kahler, Charlene M.

    2012-01-01

    The Gram-negative bacterial cell envelope consists of an inner membrane (IM) that surrounds the cytoplasm and an asymmetrical outer-membrane (OM) that forms a protective barrier to the external environment. The OM consists of lipopolysaccahride (LPS), phospholipids, outer membrane proteins (OMPs), and lipoproteins. Oxidative protein folding mediated by periplasmic oxidoreductases is required for the biogenesis of the protein components, mainly constituents of virulence determinants such as pili, flagella, and toxins, of the Gram-negative OM. Recently, periplasmic oxidoreductases have been implicated in LPS biogenesis of Escherichia coli and Neisseria meningitidis. Differences in OM biogenesis, in particular the transport pathways for endotoxin to the OM, the composition and role of the protein oxidation, and isomerization pathways and the regulatory networks that control them have been found in these two Gram-negative species suggesting that although form and function of the OM is conserved, the pathways required for the biosynthesis of the OM and the regulatory circuits that control them have evolved to suit the lifestyle of each organism. PMID:23267440

  9. Acute mammary and liver transcriptome responses after an intramammary Escherichia coli lipopolysaccharide challenge in postpartal dairy cows

    PubMed Central

    Minuti, Andrea; Zhou, Zheng; Graugnard, Daniel E; Rodriguez-Zas, Sandra L; Palladino, Alejandro R; Cardoso, Felipe C; Trevisi, Erminio; Loor, Juan J

    2015-01-01

    The study investigated the effect of an intramammary lipopolysaccharide (LPS) challenge on the bovine mammary and liver transcriptome and its consequences on metabolic biomarkers and liver tissue composition. At 7 days of lactation, 7 cows served as controls (CTR) and 7 cows (LPS) received an intramammary Escherichia coli LPS challenge. The mammary and liver tissues for transcriptomic profiling were biopsied at 2.5 h from challenge. Liver composition was evaluated at 2.5 h and 7 days after challenge, and blood biomarkers were analyzed at 2, 3, 7 and 14 days from challenge. In mammary tissue, the LPS challenge resulted in 189 differentially expressed genes (DEG), with 20 down-regulated and 169 up-regulated. In liver tissue, there were 107 DEG in LPS compared with CTR with 42 down-regulated and 65 up-regulated. In mammary, bioinformatics analysis highlighted that LPS led to activation of NOD-like receptor signaling, Toll-like receptor signaling, RIG-I-like receptor signaling and apoptosis pathways. In liver, LPS resulted in an overall inhibition of fatty acid elongation in mitochondria and activation of the p53 signaling pathway. The LPS challenge induced changes in liver lipid composition, a systemic inflammation (rise of blood ceruloplasmin and bilirubin), and an increase in body fat mobilization. The data suggest that cells within the inflamed mammary gland respond by activating mechanisms of pathogen recognition. However, in the liver the response likely depends on mediators originating from the udder that affect liver functionality and specifically fatty acid metabolism (?-oxidation, ketogenesis, and lipoprotein synthesis). PMID:25921778

  10. Advances and needs for endotoxin-free production strains.

    PubMed

    Taguchi, Seiichi; Ooi, Toshihiko; Mizuno, Kouhei; Matsusaki, Hiromi

    2015-11-01

    The choice of an appropriate microbial host cell and suitable production conditions is crucial for the downstream processing of pharmaceutical- and food-grade products. Although Escherichia coli serves as a highly valuable leading platform for the production of value-added products, like most Gram-negative bacteria, this bacterium contains a potent immunostimulatory lipopolysaccharide (LPS), referred to as an endotoxin. In contrast, Gram-positive bacteria, notably Bacillus, lactic acid bacteria (LAB), Corynebacterium, and yeasts have been extensively used as generally recognized as safe (GRAS) endotoxin-free platforms for the production of a variety of products. This review summarizes the currently available knowledge on the utilization of these representative Gram-positive bacteria for the production of eco- and bio-friendly products, particularly natural polyesters, polyhydroxyalkanoates, bacteriocins, and membrane proteins. The successful case studies presented here serve to inspire the use of these microorganisms as a main-player or by-player depending on their individual properties for the industrial production of these desirable targets. PMID:26362682

  11. Design, Syntheses, and Evaluation of Lipopolyamines as Anti-Endotoxin Agents

    E-print Network

    Shrestha, Anurupa

    2007-12-19

    Endotoxins, or Lipopolysaccharides (LPS) present on the surface of Gram negative bacteria play a key role in the pathogenesis of septic shock, a common clinical problem and a leading cause of mortality in critically ill patients, for which...

  12. Research paper Simultaneous metal chelate affinity purification and endotoxin

    E-print Network

    Lebendiker, Mario

    . coli using a non-ionic detergent. Endotoxin content was as low as 5 to 9 EU mg-1 with a recovery of antibody fragments of over 90%. Non-ionic detergent treatment did not compromise integrity-ionic detergent takes advantage of the hydrophobic properties of endotoxin trapping them in the detergent phase

  13. The biological activity of a liposomal complete core lipopolysaccharide vaccine.

    PubMed

    Erridge, Clett; Stewart, John; Bennett-Guerrero, Elliott; McIntosh, Thomas J; Poxton, Ian R

    2002-01-01

    A vaccine that induces humoral immunity to lipopolysaccharide (LPS), while remaining non-pyrogenic should be beneficial, as high levels of antibodies against LPS are associated with a reduced risk of adverse outcome. However, pure LPS or bacteria expressing LPS are generally considered too toxic to be used as vaccines. Recently, a novel, immunogenic complete core lipopolysaccharide vaccine has been described, which has been designed to prevent endotoxin-related inflammatory reactions in surgical and high-risk hospitalized patients. In vivo studies have shown that while administration of the vaccine to rabbits results in no toxicity over 7 days, it does induce significantly enhanced antibody responses towards a broad range of clinically relevant Gram-negative LPSs. Here we show that encapsulation of the four complete core LPS types Escherichia coli K12, Escherichia coli R1, Bacteroides fragilis and Pseudomonas aeruginosa into liposomes greatly reduces the ability of a given amount of LPS to induce TNF-alpha production in vitro from human monocytes. In contrast to previous studies of liposomal LPS, we demonstrate a reduction in activity of approximately 100,000-fold; a reduction approximately 100-1,000-fold more than that previously described. The signalling by the liposomal LPS appears to be entirely dependent on serum factors, though this can be partially restored by soluble CD14 or, to a lesser extent, by lipopolysaccharide binding protein. Time-course experiments reveal that liposomal LPS signalling shows similar kinetics to pure LPS signalling. Therefore, as well as inducing specific antibody responses, liposomal LPS demonstrates characteristics suitable for use as a vaccine to be used in human beings. PMID:11981444

  14. Bound To Shock: Protection from Lethal Endotoxemic Shock by a Novel, Nontoxic, Alkylpolyamine Lipopolysaccharide Sequestrant

    E-print Network

    Sil, Diptesh; Shrestha, Anurupa; Kimbrell, Matthew R.; Nguyen, Thuan B.; Adisechan, Ashok K.; Balakrishna, Rajalakshmi; Abbo, Benjamin G.; Malladi, Subbalakshmi S.; Miller, Kelly A.; Short, Shannon; Cromer, Jens R.; Arora, Shravan; Datta, Apurba; David, Sunil A.

    2007-08-01

    Lipopolysaccharide (LPS), or endotoxin, a structural component of gram-negative bacterial outer membranes, plays a key role in the pathogenesis of septic shock, a syndrome of severe systemic inflammation which leads to multiple-system organ failure...

  15. Contamination of nanoparticles by endotoxin: evaluation of different test methods

    PubMed Central

    2012-01-01

    Background Nanomaterials can be contaminated with endotoxin (lipopolysaccharides, LPS) during production or handling. In this study, we searched for a convenient in vitro method to evaluate endotoxin contamination in nanoparticle samples. We assessed the reliability of the commonly used limulus amebocyte lysate (LAL) assay and an alternative method based on toll-like receptor (TLR) 4 reporter cells when applied with particles (TiO2, Ag, CaCO3 and SiO2), or after extraction of the endotoxin as described in the ISO norm 29701. Results Our results indicate that the gel clot LAL assay is easily disturbed in the presence of nanoparticles; and that the endotoxin extraction protocol is not suitable at high particle concentrations. The chromogenic-based LAL endotoxin detection systems (chromogenic LAL assay and Endosafe-PTS), and the TLR4 reporter cells were not significantly perturbed. Conclusion We demonstrated that nanoparticles can interfere with endotoxin detection systems indicating that a convenient test method must be chosen before assessing endotoxin contamination in nanoparticle samples. PMID:23140310

  16. GM1 and GD1a gangliosides modulate toxic and inflammatory effects of E. coli lipopolysaccharide by preventing TLR4 translocation into lipid rafts.

    PubMed

    Nikolaeva, Svetlana; Bayunova, Lubov; Sokolova, Tatyana; Vlasova, Yulia; Bachteeva, Vera; Avrova, Natalia; Parnova, Rimma

    2015-03-01

    Exogenous gangliosides are known to inhibit the effects of Escherichia coli lipopolysaccharide (LPS) in different cells exhibiting anti-inflammatory and immunosuppressive activities. The mechanisms underlying ganglioside action are not fully understood. Because LPS recognition and receptor complex formation occur in lipid rafts, and gangliosides play a key role in their maintenance, we hypothesize that protective effects of exogenous gangliosides would depend on inhibition of LPS signaling via prevention of TLR4 translocation into lipid rafts. The effect of GM1 and GD1a gangliosides on LPS-induced toxic and inflammatory reactions in PC12 cells, and in epithelial cells isolated from the frog urinary bladder, was studied. In PC12 cells, GD1a and GM1 significantly reduced the effect of LPS on the decrease of cell survival and on stimulation of reactive oxygen species production. In epithelial cells, gangliosides decreased LPS-stimulated iNOS expression, NO, and PGE2 production. Subcellular fractionation, in combination with immunoblotting, showed that pretreatment of cells with GM1, GD1a, or methyl-?-cyclodextrin, completely eliminated the effect of LPS on translocation of TLR4 into lipid rafts. The results are consistent with the hypothesis that ganglioside-induced prevention of TLR4 translocation into lipid rafts could be a mechanism of protection against LPS in various cells. PMID:25499607

  17. Structural analysis of the lipid A isolated from Hafnia alvei 32 and PCM 1192 lipopolysaccharides[S

    PubMed Central

    Lukasiewicz, Jolanta; Jachymek, Wojciech; Niedziela, Tomasz; Kenne, Lennart; Lugowski, Czeslaw

    2010-01-01

    Hafnia alvei, a Gram-negative bacterium, is an opportunistic pathogen associated with mixed hospital infections, bacteremia, septicemia, and respiratory diseases. The majority of clinical symptoms of diseases caused by this bacterium have a lipopolysaccharide (LPS, endotoxin)-related origin. The lipid A structure affects the biological activity of endotoxins predominantly. Thus, the structure of H. alvei lipid A was analyzed for the first time. The major form, asymmetrically hexa-acylated lipid A built of ?-d-GlcpN4P-(1?6)-?-d-GlcpN1P substituted with (R)-14:0(3-OH) at N-2 and O-3, 14:0(3-(R)-O-12:0) at N-2?, and 14:0(3-(R)-O-14:0) at O-3?, was identified by ESI-MSn and MALDI-time-of-flight (TOF) MS. Comparative analysis performed by MS suggested that LPSs of H. alvei 32, PCM 1192, PCM 1206, and PCM 1207 share the identified structure of lipid A. LPSs of H. alvei are yet another example of enterobacterial endotoxins having the Escherichia coli-type structure of lipid A. The presence of hepta-acylated forms of H. alvei lipid A resulted from the addition of palmitate (16:0) substituting 14:0(3-OH) at N-2 of the ?-GlcpN residue. All the studied strains of H. alvei have an ability to modify their lipid A structure by palmitoylation. PMID:19706748

  18. Neutralizing and cross-reactive antibodies against enterobacterial lipopolysaccharide.

    PubMed

    Müller-Loennies, Sven; Brade, Lore; Brade, Helmut

    2007-09-01

    Lipopolysaccharide (LPS, endotoxin) elicits an immune reaction which is responsible for many of the harmful effects seen in septic shock patients. The eradication of bacteria by antibiotics is insufficient to resolve the pathology due to the lack of LPS neutralization. LPS-neutralizing antibodies have been described; however, these were specific for the serotype of the infecting bacteria and thus not useful for the treatment of septic shock patients. Structural analyses revealed that the LPS structures of Escherichia coli and Salmonella are structurally conserved in the inner core region. Using whole LPS and a panel of neoglycoconjugates containing purified LPS oligosaccharides, which we have obtained from all E. coli core types (K-12, R1, R2, R3 and R4), Salmonella enterica, and the mutant strain E. coli J-5, we have identified an epitope which is bound with high affinity by the monoclonal antibody WN1 222-5, which has been shown previously shown to be cross-reactive against a large collection of blood, fecal, and urinary isolates of E. coli, S. enterica, some Citrobacter, independently of the serotype [Di Padova, F.E., Brade, H., Barclay, G.R., Poxton, I.R., Liehl, E., Schuetze, E., Kocher, H.P., Ramsay, G., Schreier, M.H., McClelland, D.B., Rietschel, E.T., 1993. A broadly cross-protective monoclonal antibody binding to Escherichia coli and Salmonella lipopolysaccharides. Infect. Immun. 61, 3863-3872]. Importantly, WN1 222-5 was protective in various models of endotoxic shock. The minimal structural element necessary for high-affinity binding consists of R(1)-alpha-d-Glcp-(1-->3)-[l-alpha-d-Hepp-(1-->7)]-l-alpha-d-Hepp 4P-(1-->3)-R(2) (R(1), R(2)=additional sugars of LPS) in which the side-chain heptose and the 4-phosphate on the branched heptose are the main determinants of the epitope. Additional sugars of the outer core (R(1)) enhance the affinity, whereas loss of an intact Kdo region and/or lipid A (R(2)) prevent binding. The identification of the epitope provides the structural basis for the rational development of a potential vaccine against E. coli LPS. PMID:17544324

  19. Statistical optimization of medium composition and culture condition for the production of recombinant anti-lipopolysaccharide factor of Eriocheir sinensis in Escherichia coli

    NASA Astrophysics Data System (ADS)

    Jiang, Shan; Liu, Mei; Wang, Baojie; Jiang, Keyong; Wang, Lei

    2011-11-01

    Anti-lipopolysaccharide factors (ALFs) are important antimicrobial peptides that are isolated from some aquatic species. In a previous study, we isolated ALF genes from Chinese mitten crab, Eriocheir sinensis. In this study, we optimized the production of a recombinant ALF by expressing E. sinensis ALF genes in Escherichia coli maintained in shake-flasks. In particular, we focused on optimization of both the medium composition and the culture condition. Various medium components were analyzed by the Plackett-Burman design, and two significant screened factors, (NH4)2SO4 and KH2PO4, were further optimized via the central composite design (CCD). Based on the CCD analysis, we investigated the induction start-up time, the isopropylthio-D-galactoside (IPTG) concentration, the post-induction time, and the temperature by response surface methodology. We found that the highest level of ALF fusion protein was achieved in the medium containing 1.89 g/L (NH4)2SO4 and 3.18 g/L KH2PO4, with a cell optical density of 0.8 at 600 nm before induction, an IPTG concentration of 0.5 mmol/L, a post-induction temperature of 32.7°C, and a post-induction time of 4 h. Applying the whole optimization strategy using all optimal factors improved the target protein content from 6.1% (without optimization) to 13.2%. We further applied the optimized medium and conditions in high cell density cultivation, and determined that the soluble target protein constituted 10.5% of the total protein. Our identification of the economic medium composition, optimal culture conditions, and details of the fermentation process should facilitate the potential application of ALF for further research.

  20. Vagus nerve stimulation attenuates the systemic inflammatory response to endotoxin

    NASA Astrophysics Data System (ADS)

    Borovikova, Lyudmila V.; Ivanova, Svetlana; Zhang, Minghuang; Yang, Huan; Botchkina, Galina I.; Watkins, Linda R.; Wang, Haichao; Abumrad, Naji; Eaton, John W.; Tracey, Kevin J.

    2000-05-01

    Vertebrates achieve internal homeostasis during infection or injury by balancing the activities of proinflammatory and anti-inflammatory pathways. Endotoxin (lipopolysaccharide), produced by all gram-negative bacteria, activates macrophages to release cytokines that are potentially lethal. The central nervous system regulates systemic inflammatory responses to endotoxin through humoral mechanisms. Activation of afferent vagus nerve fibres by endotoxin or cytokines stimulates hypothalamic-pituitary-adrenal anti-inflammatory responses. However, comparatively little is known about the role of efferent vagus nerve signalling in modulating inflammation. Here, we describe a previously unrecognized, parasympathetic anti-inflammatory pathway by which the brain modulates systemic inflammatory responses to endotoxin. Acetylcholine, the principle vagal neurotransmitter, significantly attenuated the release of cytokines (tumour necrosis factor (TNF), interleukin (IL)-1?, IL-6 and IL-18), but not the anti-inflammatory cytokine IL-10, in lipopolysaccharide-stimulated human macrophage cultures. Direct electrical stimulation of the peripheral vagus nerve in vivo during lethal endotoxaemia in rats inhibited TNF synthesis in liver, attenuated peak serum TNF amounts, and prevented the development of shock.

  1. Mechanisms of endotoxin tolerance. The role of the spleen.

    PubMed Central

    Greisman, S E; Young, E J; Workman, J B; Ollodart, R M; Hornick, R B

    1975-01-01

    Splenectomy markedly impaired the production of circulating anti-endotoxin antibodies during the initial 10 days after .v. administration of a Boivin preparation of Escherichia coli endotoxin (ET) in both rabbit and man. Increase in antibodies with secondary (flocculating and bactericidal) activities were virtually abolished, whereas increases in antibodies with primary (binding) activity were significantly reduced. On the basis of these findings, splenectomized rabbit and man were employed to test the hypothesis that the early phase (less than 72 h) of pyrogenic tolerance to endotoxin is independent of anti-endotoxin antibody but that such antibody contributes significantly to the later phase (less than or equal to 72 h) of tolerance. In the splenectomized rabbit, the initial pyrogenic reponses to ET and the subsequent tolerant responses at 24 and 48 h were comparable to sham-operated controls... PMID:1104660

  2. Anti-endotoxin therapy in primate bacteremia with HA-1A and BPI.

    PubMed Central

    Rogy, M A; Moldawer, L L; Oldenburg, H S; Thompson, W A; Montegut, W J; Stackpole, S A; Kumar, A; Palladino, M A; Marra, M N; Lowry, S F

    1994-01-01

    OBJECTIVE: The in vivo neutralizing activities of an anti-lipopolysaccharide (LPS) antibody HA-1A (Centoxin [Centocor, Malvern, PA]), a human immunoglobulin M monoclonal antibody, and of bactericidal/permeability-increasing protein (BPI), an endogenously produced human LPS-neutralizing protein, were studied in a primate model of lethal Escherichia coli bacteremia. SUMMARY BACKGROUND DATA: HA-1A has been used with variable success against LPS activity in some animal models and in a recently reported clinical trial. However, no data assessing the efficacy of this agent in subhuman primates is available. Bactericidal/permeability-increasing protein is a product of polymorphomononuclear cells (PMNs) that is stored in azurophilic granules and exhibits LPS-neutralizing activity in vitro and in some in vivo models. METHODS: Immediately after E. coli infusion and in a blinded fashion, three baboons were treated with BPI (5 mg/kg bolus infusion and 95 micrograms/kg/min infusion over 4 hr). Three animals received 3 mg/kg BW of HA-1A, whereas another three baboons received a placebo treatment. RESULTS: The BPI-treated animals demonstrated significantly (p < 0.03) lower circulating LPS-limulus amoebocyte lysate (LAL) activity compared with the control animals, but this reduction in LPS-LAL activity was not associated with improved survival. HA-1A treatment did not reduce LPS-LAL activity. However, both BPI and HA-1A treatment did attenuate the pro-inflammatory cytokine response. CONCLUSION: The current data suggests that incomplete neutralization of endotoxin activity does not alter mortality from severe bacteremia. Given the diversity of mediator production under such circumstances, a strategy of combination therapy in the form of anti-lipopolysaccharide and anticytokine treatment may be necessary to achieve optimal survival. PMID:8024362

  3. Cynandione A attenuates lipopolysaccharide-induced production of inflammatory mediators via MAPK inhibition and NF-?B inactivation in RAW264.7 macrophages and protects mice against endotoxin shock.

    PubMed

    Kim, Sung Hwan; Lee, Tae Hoon; Lee, Sang Min; Park, Ji Hae; Park, Keun Hyung; Jung, Mira; Jung, Hana; Mohamed, Mohamed Antar Aziz; Baek, Nam-In; Chung, In Sik; Kim, Jiyoung

    2015-07-01

    Cynanchum wilfordii has been traditionally used in eastern Asia for the treatment of various diseases such as gastrointestinal diseases and arteriosclerosis. Cynandione A (CA), an acetophenone, is one of major constituents from roots of C. wilfordii. In the present study, the anti-inflammatory activities of CA were investigated in lipopolysaccharide (LPS)-treated RAW264.7 macrophages and LPS-administered C57BL/6?N mice. CA significantly decreased LPS-induced production of nitric oxide and prostaglandin E2 in a dose-dependent manner, while CA up to 200??M did not exhibit cytotoxic activity. Our data also showed that CA significantly attenuated expression of iNOS and COX-2 in LPS-stimulated macrophages. CA inhibited phosphorylation of I?B-? and MAP kinases such as ERK and p38. Furthermore, we demonstrated that CA inhibited translocation of NF-?B to the nucleus, transcription of the NF-?B minimal promoter and NF-?B DNA binding activity. Administration of CA significantly decreased the plasma levels of pro-inflammatory cytokines such as TNF-?, IL-6, and IL-1? in LPS-injected mice and improved survival of septic mice with lethal endotoxemia. These results demonstrate that CA has effective inhibitory effects on production of inflammatory mediators via suppressing activation of NF-?B and MAPK signaling pathways, suggesting that CA may be used as a potential anti-inflammatory agent for the prevention and treatment of inflammatory diseases. PMID:25361770

  4. The natural immunity to evolutionary atavistic endotoxin for human cancer.

    PubMed

    Moncevi?i?t?-Eringien?, Elena; Rotkevi?, Kristina; Grikienis, Ruta Grikienyte

    2015-11-01

    We propose a new theory of the immunological control of cancer corresponding to the hypothesis that the specific natural immunity to evolutionary atavistic endotoxin has a potential role in human cancer prevention. The results of our studies have shown that IgMNAE, i.e. endogenous or spontaneous IgM class antibodies to enterobacterial lipopolysaccharide molecules (lipid A), control the immune mechanisms responsible for the internal medium stability not only against the damaging impact of the carcinogenic factors, but also against the malignant transformation of its own degenerated cells. Among people who in 1979 and 1982 had IgMNAE in their blood serum, after 15-30years fell ill with cancer 10%, versus 15% among people who had no IgMNAE (p<0.05). Therefore, it is possible to maintain that the stimulation of IgMNAE synthesis would help in the destruction and elimination of damaged somatic cells or prevent their mechanisms from the formation of invasiveness, metastatic and other properties of their parasitism. In the mechanism of the natural immunity to endotoxin it is possible to see the formation of the respective evolutionary protective reactions which protect the damaged cells from acquiring resistance to damaging factors and thus from becoming an independent new parasitic population. Thereby the presented theory of the immunological control of cancer has a causal connection with our evolutionary resistance theory of the origin of cancer. Collectively, these data suggest that activation of natural immunity to endotoxin and production of vaccines against evolutionary atavistic endotoxin or gram-negative bacterial endotoxin can be helpful when applied in cancer prophylaxis for persons with a low level of natural immunity to endotoxin and perhaps in creating immunotherapeutic methods for stopping the endogenous parasitism of tumour cells by binding IgMNAE to atavistic endotoxin in cancer patients. PMID:26350411

  5. RECOMBINANT BOVINE SOLUBLE CD14 REDUCES FATALITY OF ENDOTOXIN CHALLENGED MICE

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Endotoxin, or lipopolysaccharide (LPS), has been demonstrated to be responsible for the pathogenesis of Gram-negative bacterial infections, such as bovine coliform mastitis. In the US, 300,000 dairy cows are removed from herds or die annually because of acute coliform mastitis. Standard therapy for ...

  6. Endotoxin and Cancer

    PubMed Central

    Lundin, Jessica I.; Checkoway, Harvey

    2009-01-01

    Objective Exposure to endotoxin, a component of gram-negative bacterial cell walls, is widespread in many industrial settings and in the ambient environment. Heavy-exposure environments include livestock farms, cotton textile facilities, and saw mills. Concentrations are highly variable in non-occupational indoor and outdoor environments. Endotoxin is a potent inflammagen with recognized health effects, including fever, shaking chills, septic shock, toxic pneumonitis, and respiratory symptoms. Somewhat paradoxically, given the putative role of inflammation in carcinogenesis, various lines of evidence suggest that endotoxin may prevent cancer initiation or limit tumor growth. The hypothesis that components of bacteria may retard cancer progression dates back to William B. Coley’s therapeutic experiments (“bacterial vaccine”) in the 1890s. Data sources In this article, we review epidemiologic, clinical trial, and experimental studies pertinent to the hypothesis that endotoxin prevents cancer. Since the 1970s, epidemiologic studies of cotton textile and other endotoxin-exposed occupational groups have consistently demonstrated reduced lung cancer risks. Experimental animal toxicology research and some limited therapeutic trials in cancer patients offer additional support for an anticarcinogenic potential. The underlying biological mechanisms of anticarcinogenesis are not entirely understood but are thought to involve the recruitment and activation of immune cells and proinflammatory mediators (e.g., tumor necrosis factor ? and interleukin-1 and -6). Conclusions In view of the current state of knowledge, it would be premature to recommend endotoxin as a cancer-chemopreventive agent. Nonetheless, further epidemiologic and experimental investigations that can clarify further dose–effect and exposure–timing relations could have substantial public health and basic biomedical benefits. PMID:19750096

  7. Lipopolysaccharide found in aseptic loosening of patients with inflammatory arthritis.

    PubMed

    Nalepka, Jennifer L; Lee, Michael J; Kraay, Matthew J; Marcus, Randall E; Goldberg, Victor M; Chen, Xin; Greenfield, Edward M

    2006-10-01

    Aseptic loosening of orthopaedic implants occurs in the absence of clinical signs of infection. Nevertheless, bacterial endotoxins derived from subclinical infections, systemic sources, or the implant manufacturing process may contribute to aseptic loosening. Also, the rate of implant infection is greater in patients with inflammatory arthritis than in patients with osteoarthritis. We hypothesized that lipopolysaccharide, the classic endotoxin derived from gram-negative bacteria, is more prevalent in periprosthetic tissue surrounding aseptically loose implants in patients with inflammatory arthritis than in patients with osteoarthritis. To test this, we used a modified Limulus amebocyte assay not affected by beta-glucan-like molecules in mammalian tissues. Lipopolysaccharide rarely was detected in periprosthetic tissue from patients with osteoarthritis and aseptic loosening (one of six patients). In contrast, lipopolysaccharide was detected despite the absence of any clinical signs of infection in peri-prosthetic tissue from all four patients with inflammatory arthritis (rheumatoid arthritis, juvenile rheumatoid arthritis, and systemic lupus erythematosus). Lipopolysaccharide also was detected in two patients with gram-negative infections, who were included as positive control subjects. Endotoxins derived from low-grade or systemic bacteremia may be important contributors to aseptic loosening particularly in patients with autoimmune conditions such as inflammatory arthritis. PMID:16735873

  8. Removal of endotoxin from water by microfiltration through a microporous polyethylene hollow-fiber membrane

    SciTech Connect

    Sawada, Y.; Fujii, R.; Igami, I.; Kawai, A.; Kamiki, T.; Niwa, M.

    1986-04-01

    The microporous polyethylene hollow-fiber membrane has a unique microfibrile structure throughout its depth and has been found to possess the functions of filtration and adsorption of endotoxin in water. The membrane has a maximum pore diameter of approximately 0.04 micron, a diameter which is within the range of microfiltration. Approximately 10 and 20% of the endotoxin in tap water and subterranean water, respectively, was smaller than 0.025 micron. Endotoxin in these water sources was efficiently removed by the microporous polyethylene hollow-fiber membrane. Escherichia coli O113 culture broth contained 26.4% of endotoxin smaller than 0.025 micron which was also removed. Endotoxin was leaked into the filtrate only when endotoxin samples were successively passed through the membrane. These results indicate that endotoxin smaller than the pore size of the membrane was adsorbed and then leaked into the filtrate because of a reduction in binding sites. Dissociation of /sup 3/H-labeled endotoxin from the membrane was performed, resulting in the removal of endotoxin associated with the membrane by alcoholic alkali at 78% efficiency.

  9. Response of Saccharomyces cerevisiae to the Stimulation of Lipopolysaccharide

    PubMed Central

    Shen, Lulu; Li, Ye; Jiang, Linghuo; Wang, Xiaoyuan

    2014-01-01

    Lipopolysaccharide, known as endotoxin, can stimulate potent host immune responses through the complex of Toll-like-receptor 4 and myeloid differentiation protein 2; but its influence on Saccharomyces cerevisiae, a model organism for studying eukaryotes, is not clear. In this study, we found that lipopolysaccharide-treated S. cerevisiae cells could be stained by methylene blue, but did not die. Transcriptional profiling of the lipopolysaccharide-treated S. cerevisiae cells showed that 5745 genes were modulated: 2491 genes up-regulated and 3254 genes down-regulated. Significantly regulated genes (460 up-regulated genes and 135 down-regulated genes) in lipopolysaccharide-treated S. cerevisiae cells were analyzed on Gene Ontology, and used to establish physical protein-protein interaction network and protein phosphorylation network. Based on these analyses, most of the regulated genes in lipopolysaccharide-treated S. cerevisiae cells were related to cell wall, membrane, peroxisome and mitochondrion. Further experiments demonstrated that lipopolysaccharide stimulation caused the exposure of phosphatidylserine and the increase of mitochondrial membrane potential in S. cerevisiae cells, but levels of intracellular reactive oxygen species and metacaspase activation were not increased. This study demonstrated that lipopolysaccharide stimulation causes significant changes in S. cerevisiae cells, and the results would contribute to understand the response of eukaryotic cells to lipopolysaccharide stimulation. PMID:25105496

  10. 21 CFR 866.3210 - Endotoxin assay.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ...2010-04-01 2010-04-01 false Endotoxin assay. 866.3210 Section 866.3210 Food and...Serological Reagents § 866.3210 Endotoxin assay. (a) Identification. An endotoxin assay is a device that uses serological...

  11. Effect of Heat-Killed Escherichia coli, Lipopolysaccharide, and Muramyl Dipeptide Treatments on the Immune Response Phenotype and Allergy in Neonatal Pigs Sensitized to the Egg White Protein Ovomucoid

    PubMed Central

    Schmied, Julie; Rupa, Prithy; Garvie, Sarah

    2012-01-01

    Predisposition to food allergies may reflect a type 2 immune response (IR) bias in neonates due to the intrauterine environment required to maintain pregnancy. The hygiene hypothesis states that lack of early environmental stimulus leading to inappropriate development and bias in IR may also contribute. Here, the ability of heat-killed Escherichia coli, lipopolysaccharide (LPS), or muramyl dipeptide (MDP) to alter IR bias and subsequent allergic response in neonatal pigs was investigated. Three groups of three litters of pigs (12 pigs/litter) were given intramuscular injections of E. coli, LPS, MDP, or phosphate-buffered saline (PBS) (control) and subsequently sensitized to the egg white allergen ovomucoid using an established protocol. To evaluate change in IR bias, immunoglobulin isotype-associated antibody activity (AbA), concentrations of type 1 and 2 and proinflammatory cytokines released from mitogen-stimulated blood mononuclear cells, and the percentage of T-regulatory cells (T-regs) in blood were measured. Clinical signs of allergy were assessed after oral challenge with egg white. The greatest effect on IR bias was observed in MDP-treated pigs, which had a type 2-biased phenotype by isotype-specific AbA, cytokine production, and a low proportion of T-regs. LPS-treated pigs had decreased type 1- and type 2-associated AbA. E. coli-treated pigs displayed increased response to Ovm as AbA and had more balanced cytokine profiles, as well as the highest proportion of T-regs. Accordingly, pigs treated with MDP were more susceptible to allergy than PBS controls, while pigs treated with LPS were less susceptible. Treatment with E. coli did not significantly alter the frequency of clinical signs. PMID:23081818

  12. Effect of heat-killed Escherichia coli, lipopolysaccharide, and muramyl dipeptide treatments on the immune response phenotype and allergy in neonatal pigs sensitized to the egg white protein ovomucoid.

    PubMed

    Schmied, Julie; Rupa, Prithy; Garvie, Sarah; Wilkie, Bruce

    2012-12-01

    Predisposition to food allergies may reflect a type 2 immune response (IR) bias in neonates due to the intrauterine environment required to maintain pregnancy. The hygiene hypothesis states that lack of early environmental stimulus leading to inappropriate development and bias in IR may also contribute. Here, the ability of heat-killed Escherichia coli, lipopolysaccharide (LPS), or muramyl dipeptide (MDP) to alter IR bias and subsequent allergic response in neonatal pigs was investigated. Three groups of three litters of pigs (12 pigs/litter) were given intramuscular injections of E. coli, LPS, MDP, or phosphate-buffered saline (PBS) (control) and subsequently sensitized to the egg white allergen ovomucoid using an established protocol. To evaluate change in IR bias, immunoglobulin isotype-associated antibody activity (AbA), concentrations of type 1 and 2 and proinflammatory cytokines released from mitogen-stimulated blood mononuclear cells, and the percentage of T-regulatory cells (T-regs) in blood were measured. Clinical signs of allergy were assessed after oral challenge with egg white. The greatest effect on IR bias was observed in MDP-treated pigs, which had a type 2-biased phenotype by isotype-specific AbA, cytokine production, and a low proportion of T-regs. LPS-treated pigs had decreased type 1- and type 2-associated AbA. E. coli-treated pigs displayed increased response to Ovm as AbA and had more balanced cytokine profiles, as well as the highest proportion of T-regs. Accordingly, pigs treated with MDP were more susceptible to allergy than PBS controls, while pigs treated with LPS were less susceptible. Treatment with E. coli did not significantly alter the frequency of clinical signs. PMID:23081818

  13. Comparison of the binding of gram-negative bacterial endotoxin by polymyxin B sulphate, colistin sulphate and colistin sulphomethate sodium.

    PubMed

    Rogers, M J; Cohen, J

    1986-01-01

    Polymyxins are cyclic polypeptide antibiotics. In addition to their bactericidal activity they bind lipid A and neutralize the biological effects of bacterial endotoxin. We have studied the three available polymyxin preparations: polymyxin B sulphate (PB), colistin sulphate (CS) and colistin sulphomethate sodium (CMS), and compared their endotoxin binding capacity at equivalent therapeutic dosage. Each polymyxin was bound to a column of Sepharose 4B and challenged with 5 micrograms of endotoxin from Escherichia coli O127:B8. Recovery of endotoxin in the eluate was measured by a quantitative Limulus lysate microassay. PB and CS bound 94% of the challenge dose, CMS 89% and the control column (Sepharose alone) 24%. These results suggest that parenteral CMS (the least toxic polymyxin) retains useful anti-endotoxin capacity, and that in neutropenic patients, oral polymyxin may exert both anti-endotoxin and antimicrobial effects. PMID:3011678

  14. Maternal supplementation with fishmeal protects against late gestation endotoxin-induced fetal programming of the ovine hypothalamic-pituitary-adrenal axis.

    PubMed

    Fisher, R E; Or'Rashid, M; Quinton, M; AlZahal, O; Boermans, H J; McBride, B W; Karrow, N A

    2014-06-01

    Adverse uterine environments caused by maternal stress (such as bacterial endotoxin) can alter programming of the fetal hypothalamic-pituitary-adrenal axis (HPAA) rendering offspring susceptible to various adulthood diseases. Thus, protection against this type of stress may be critical for ensuring offspring health. The present study was designed to determine if maternal supplementation with omega-3 polyunsaturated fatty acids (n-3 PUFAs) during pregnancy helps to protect against stress-induced fetal programming. Briefly, 53 ewes were fed a diet supplemented with fishmeal (FM) or soybean meal (SM) from day 100 of gestation (gd100) through lactation. On gd135, half the ewes from each dietary group were challenged with either 1.2 ?g/kg Escherichia coli lipopolysaccharide (LPS) endotoxin, or saline as the control. The offspring's cortisol response to weaning stress was assessed 50 days postpartum by measuring serum cortisol concentrations 0, 6 and 24 h post weaning. Twenty-four hours post-weaning, lambs were subjected to an adrenocorticotropic hormone (ACTH) challenge (0.5 ?g/kg) and serum cortisol concentrations were measured 0, 0.25, 0.5, 1 and 2 h post injection. At 5.5 months of age, offspring were also challenged with 400 ng/kg of LPS, and serum cortisol concentrations were measured 0, 2, 4 and 6 h post challenge. Interestingly, female offspring born to FM+LPS mothers had a greater cortisol response to weaning and endotoxin challenge compared with the other treatments, while female offspring born to SM+LPS mothers had a faster cortisol response to the ACTH stressor. Additionally, males born to FM+LPS mothers had a greater cortisol response to the ACTH challenge than the other treatments. Overall, FM supplementation during gestation combined with LPS challenge alters HPAA responsiveness of the offspring into adulthood. PMID:24901660

  15. Influence of an in vivo endotoxin challenge on ex vivo phagocytic and oxidative burst capacities of bovine neutrophils

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Neutrophils promote health by reducing the early growth of invading pathogens. The objective of this study was to elucidate the temporal effects of an exogenous endotoxin (lipopolysaccharide; LPS) challenge on neutrophil function. Brahman heifers (186.1±11.8 kg; n=6) were challenged with an intraven...

  16. The effect of yeast cell wall supplementation on the metabolic responses of crossbred heifers to endotoxin challenge

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This study examined the effect of feeding yeast cell wall (YCW) products on the metabolic responses of newly-received heifers to endotoxin (lipopolysaccharide; LPS) challenge. Heifers (n=24; 218.9±2.4 kg) were obtained from commercial sale barns and transported to the Texas Tech University Beef Cent...

  17. The effect of yeast cell wall supplementation on the physiological and acute phase responses of crossbred heifers to endotoxin challenge

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A study was conducted to determine the effect of feeding yeast cell wall (YCW) products on the physiological and acute phase responses of crossbred newly-received heifers to endotoxin (lipopolysaccharide; LPS) challenge. Heifers (n=24; 218.9+/-2.4 kg) were obtained from commercial sale barns and tra...

  18. Dried citrus pulp modulates the physiological and acute phase responses of crossbred heifers to an endotoxin challenge

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This study examined the effect of feeding dried citrus pulp (CP) pellets on the physiological and acute phase responses (APR) of newly-received crossbred heifers to an endotoxin (lipopolysaccharide; LPS) challenge. Heifers (n=24; 218.3±2.4 kg) were obtained from commercial sale barns and transported...

  19. Sexually dimorphic secretion of cortisol but not catecholamines in response to an endotoxin challenge in beef cattle

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This study was designed to determine the effect of endotoxin (lipopolysaccharide; LPS) challenge on secretion of the adrenal stress-related hormones cortisol, epinephrine, and norepinephrine in bull and heifer calves. Brahman calves (n = 12; 269 ± 11.7 kg) were randomly selected from the fall 2007 c...

  20. Modulation of the metabolic response to an endotoxin challenge in Brahman heifers through OmniGen-AF supplementation

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This study examined the effect of feeding OmniGen-AF (OG; Prince Agri Products) on the metabolic response of newly-weaned heifers to an endotoxin (lipopolysaccharide; LPS) challenge. Brahman heifers (n=24; 183±5 kilograms) from the Texas AgriLife Research Center in Overton, TX, were separated into 2...

  1. Ultrasound body composition traits response to an endotoxin challenge in Brahman heifers supplemented with Omnigen-AF

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This study examined the effect of feeding OmniGen-AF (OG; Prince Agri Products) on the body composition traits response of newly-weaned heifers to an endotoxin (lipopolysaccharide; LPS) challenge. Brahman heifers (n=24; 183 ± 5 kg) from the Texas AgriLife Research Center in Overton, TX, were separat...

  2. Temperament influences endotoxin-induced changes in rectal temperature, sickness behavior, and plasma epinephrine concentrations in bulls

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This study was designed to determine the influence of temperament on endotoxin (lipopolysaccharide; LPS) induced changes in body temperature and the secretion of cortisol and epinephrine. Purebred Brahman bulls were selected based on temperament score (average of exit velocity, EV, and pen score, PS...

  3. OmniGen-AF supplementation modulated the physiological and acute phase responses of Brahman heifers to an endotoxin challenge

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This study examined the effect of feeding OmniGen-AF (OG; Prince Agri Products) on the physiological and acute phase responses (APR) of newly-weaned heifers to an endotoxin (lipopolysaccharide; LPS) challenge. Brahman heifers (n=24; 183±5 kilograms) from the Texas AgriLife Research Center in Overton...

  4. Tumor necrosis factor and interleukin 1 as mediators of endotoxin-induced beneficial effects

    SciTech Connect

    Urbaschek, R.; Urbaschek, B.

    1987-09-01

    Bacterial lipopolysaccharides or endotoxins are known to induce tumor necrosis; enhanced nonspecific resistance to bacterial, viral, and parasitic infections and to radiation sickness; and tolerance to lethal doses of endotoxin. These beneficial effects are achieved by pretreatment with minute amounts of endotoxin. Recombinant tumor necrosis factor (TNF) and interleukin 1 (IL-1) are among the mediators capable of invoking radioprotection or resistance to the consequences of cecal ligation and puncture. Both cytokines are potent inducers of serum colony-stimulating factor (CSF) in C3H/HeJ mice (low responders to endotoxin). The number of splenic granulocyte-macrophage precursors was found to increase 5 days after injection of TNF in these mice. Although with IL-1 no increase in the number of granulocyte-macrophage colonies occurred in culture in the presence of serum CSF, a marked stimulation was observed when TNF was added. This stimulation of myelopoiesis observed in vivo and in vitro may be related to the radioprotective effect of TNF. The data presented suggest that TNF and IL-1 released after injection of endotoxin participate in the mediation of endotoxin-induced enhancement of nonspecific resistance and stimulation of hematopoiesis. 76 references.

  5. Oxidative degradation of endotoxin by advanced oxidation process (O3/H2O2 & UV/H2O2).

    PubMed

    Oh, Byung-Taek; Seo, Young-Suk; Sudhakar, Dega; Choe, Ji-Hyun; Lee, Sang-Myeong; Park, Youn-Jong; Cho, Min

    2014-08-30

    The presence of endotoxin in water environments may pose a serious public health hazard. We investigated the effectiveness of advanced oxidative processes (AOP: O3/H2O2 and UV/H2O2) in the oxidative degradation of endotoxin. In addition, we measured the release of endotoxin from Escherichia coli following typical disinfection methods, such as chlorine, ozone alone and UV, and compared it with the use of AOPs. Finally, we tested the AOP-treated samples in their ability to induce tumor necrosis factor alpha (TNF-?) in mouse peritoneal macrophages. The production of hydroxyl radical in AOPs showed superior ability to degrade endotoxin in buffered solution, as well as water samples from Korean water treatment facilities, with the ozone/H2O2 being more efficient compared to UV/H2O2. In addition, the AOPs proved effective not only in eliminating E. coli in the samples, but also in endotoxin degradation, while the standard disinfection methods lead to the release of endotoxin following the bacteria destruction. Furthermore, in the experiments with macrophages, the AOPs-deactivated endotoxin lead to the smallest induction of TNF-?, which shows the loss of inflammation activity, compared to ozone treatment alone. In conclusion, these results suggest that AOPs offer an effective and mild method for endotoxin degradation in the water systems. PMID:25038578

  6. Lipopolysaccharides and divalent cations are involved in the formation of an assembly-competent intermediate of outer-membrane protein PhoE of E.coli.

    PubMed Central

    de Cock, H; Tommassen, J

    1996-01-01

    To identify the requirements for the biogenesis of outer-membrane proteins in Gram-negative bacteria, the sorting and assembly of the trimeric, pore-forming protein PhoE was studied in vitro. Purified lipopolysaccharide (LPS) in combination with low amounts of Triton X-100 and divalent cations induced the formation of folded monomers. LPS of deep-rough strains was far less efficient in the formation of folded monomers than wild-type LPS was. These folded monomers could be converted into heat-stable trimers upon addition of outer membranes and higher amounts of Triton X-100. Trimerization could precede the insertion step. These in vitro data suggest that the assembly in vivo proceeds sequentially by (i) formation of a folded monomer by interaction with LPS; (ii) sorting of the folded monomers to assembly sites in the outer membrane; (iii) trimerization; and (iv) insertion. Images PMID:8896450

  7. The Chemical Composition of Endotoxin Isolated from Intestinal Strain of Desulfovibrio desulfuricans

    PubMed Central

    Lodowska, Jolanta; Wolny, Daniel; Jaworska-Kik, Marzena; Kurkiewicz, S?awomir; Dzier?ewicz, Zofia; W?glarz, Ludmi?a

    2012-01-01

    Desulfovibrio desulfuricans anaerobes are constituents of human alimentary tract microflora. There are suggestions that they take part in the pathogenesis of periodontitis and some gastrointestinal inflammatory disorders, such as ulcerative colitis or Crohn's disease. Endotoxin is one of Gram-negative bacteria cellular components that influence these microorganisms pathogenicity. Endotoxin is a lipid-polisaccharide heteropolymer consisting of three elements: lipid A, core oligosaccharide, and O-specific polysaccharide, also called antigen-O. The biological activity of lipopolysaccharide (LPS) is determined by its structure. In this study, we show that rhamnose, fucose, mannose, glucose, galactose, heptose, and 2-keto-3-deoxyoctulosonic acid (Kdo) are constituents of D. desulfuricans endotoxin oligosaccharide core and O-antigen. Lipid A of these bacteria LPS is composed of glucosamine disaccharide substituted by 3-acyloxyacyl residues: ester-bound 3-(dodecanoyloxy)tetradecanoic, 3-(hexadecanoyloxy)tetradecanoic acid, and amide-bound 3-(tetradecanoyloxy)tetradecanoic acid. PMID:22629175

  8. Farm dust and endotoxin protect against allergy through A20 induction in lung epithelial cells.

    PubMed

    Schuijs, Martijn J; Willart, Monique A; Vergote, Karl; Gras, Delphine; Deswarte, Kim; Ege, Markus J; Madeira, Filipe Branco; Beyaert, Rudi; van Loo, Geert; Bracher, Franz; von Mutius, Erika; Chanez, Pascal; Lambrecht, Bart N; Hammad, Hamida

    2015-09-01

    Growing up on a dairy farm protects children from allergy, hay fever, and asthma. A mechanism linking exposure to this endotoxin (bacterial lipopolysaccharide)-rich environment with protection has remained elusive. Here we show that chronic exposure to low-dose endotoxin or farm dust protects mice from developing house dust mite (HDM)-induced asthma. Endotoxin reduced epithelial cell cytokines that activate dendritic cells (DCs), thus suppressing type 2 immunity to HDMs. Loss of the ubiquitin-modifying enzyme A20 in lung epithelium abolished the protective effect. A single-nucleotide polymorphism in the gene encoding A20 was associated with allergy and asthma risk in children growing up on farms. Thus, the farming environment protects from allergy by modifying the communication between barrier epithelial cells and DCs through A20 induction. PMID:26339029

  9. Effects of endotoxin induced lung injury and exercise in goats/sheep. Final report, 1 February 1992-2 June 1993

    SciTech Connect

    Mundie, T.G.

    1993-06-02

    This study was designed the effects of exercise performed on animals already injured with E. coli endotoxin. This would tell us whether exercise makes the lung injury worse. It would also tell us how much exercise performance is impaired. These studies were designed to give further insights into the underlying causes of acute lung injury. Premature termination of the study prevented completion of the research project. It appeared from the limited experimentation conducted that maximal exercise was impaired by endotoxin-induced lung injury. Conclusions regarding exacerbation of endotoxin-induced lung injury cannot be made.... Acute lung injury, Maximal exercise, Endotoxin.

  10. Interactions of lipopolysaccharide with lipid membranes, raft models - a solid state NMR study.

    PubMed

    Ciesielski, Filip; Griffin, David C; Rittig, Michael; Moriyón, Ignacio; Bonev, Boyan B

    2013-08-01

    Lipopolysaccharide (LPS) is a major component of the external leaflet of bacterial outer membranes, key pro-inflammatory factor and an important mediator of host-pathogen interactions. In host cells it activates the complement along with a pro-inflammatory response via a TLR4-mediated signalling cascade and shows preference for cholesterol-containing membranes. Here, we use solid state (13)C and (31)P MAS NMR to investigate the interactions of LPS from three bacterial species, Brucella melitensis, Klebsiella pneumoniae and Escherichia coli, with mixed lipid membranes, raft models. All endotoxin types are found to be pyrophosphorylated and Klebsiellar LPS is phosphonylated, as well. Carbon-13 MAS NMR indicates an increase in lipid order in the presence of LPS. Longitudinal (31)P relaxation, providing a direct probe of LPS molecular and segmental mobility, reveals a significant reduction in (31)P T1 times and lower molecular mobility in the presence of ternary lipid mixtures. Along with the ordering effect on membrane lipid, this suggests a preferential partitioning of LPS into ordered bilayer sphingomyelin/cholesterol-rich domains. We hypothesise that this is an important evolutionary drive for the selection of GPI-anchored raft-associated LPS-binding proteins as a first line of response to membrane-associated LPS. PMID:23567915

  11. Asparagine attenuates intestinal injury, improves energy status and inhibits AMP-activated protein kinase signalling pathways in weaned piglets challenged with Escherichia coli lipopolysaccharide.

    PubMed

    Wang, Xiuying; Liu, Yulan; Li, Shuang; Pi, Dingan; Zhu, Huiling; Hou, Yongqing; Shi, Haifeng; Leng, Weibo

    2015-08-28

    The intestine requires a high amount of energy to maintain its health and function; thus, energy deficits in intestinal mucosa may lead to intestinal damage. Asparagine (Asn) is a precursor for many other amino acids such as aspartate, glutamine and glutamate, which can be used to supply energy to enterocytes. In the present study, we hypothesise that dietary supplementation of Asn could alleviate bacterial lipopolysaccharide (LPS)-induced intestinal injury via improvement of intestinal energy status. A total of twenty-four weaned piglets were assigned to one of four treatments: (1) non-challenged control; (2) LPS+0 % Asn; (3) LPS+0·5 % Asn; (4) LPS+1·0 % Asn. On day 19, piglets were injected with LPS or saline. At 24 h post-injection, piglets were slaughtered and intestinal samples were collected. Asn supplementation improved intestinal morphology, indicated by higher villus height and villus height:crypt depth ratio, and lower crypt depth. Asn supplementation also increased the ratios of RNA:DNA and protein:DNA as well as disaccharidase activities in intestinal mucosa. In addition, Asn supplementation attenuated bacterial LPS-induced intestinal energy deficits, indicated by increased ATP and adenylate energy charge levels, and decreased AMP:ATP ratio. Moreover, Asn administration increased the activities of key enzymes involved in the tricarboxylic acid cycle, including citrate synthase, isocitrate dehydrogenase and ?-ketoglutarate dehydrogenase complex. Finally, Asn administration decreased the mRNA abundance of intestinal AMP-activated protein kinase-?1 (AMPK?1), AMPK?2, silent information regulator 1 (SIRT1) and PPAR? coactivator-1? (PGC1?), and reduced intestinal AMPK? phosphorylation. Collectively, these results indicate that Asn supplementation alleviates bacterial LPS-induced intestinal injury by modulating the AMPK signalling pathway and improving energy status. PMID:26277838

  12. Deoxynivalenol, but not E. coli lipopolysaccharide, changes the response pattern of intestinal porcine epithelial cells (IPEC-J2) according to its route of application.

    PubMed

    Kluess, J W; Kahlert, S; Kröber, A; Diesing, A-K; Rothkötter, H-J; Wimmers, Klaus; Dänicke, S

    2015-12-15

    The porcine intestinal epithelium is a primary target for mycotoxin deoxynivalenol (DON) and lipopolysaccharides (LPS). Although epithelial cells are exposed to these toxins mainly from the luminal-chyme compartment an exposure from the blood side resulting from systemic absorption cannot be excluded. Thus, we investigated the effect of DON and LPS, alone or combined, on porcine intestinal epithelial cells IPEC-J2 on a transcriptional, translational and functional level when administered either from apical or basolateral. IPEC-J2 cells were cultured on 12-well inserts in complete medium at 5% CO2 and 39°C and subjected to following treatments: control (CON), 2000ng/mL DON, 1?g/mL LPS or DON+LPS for 72h, either from apical or basolateral. Transepithelial electrical resistance (TEER), protein and IL-8 content were measured and microarray analysis, qRT-PCR (IL-8, zonula occludens-1 ZO-1, ?-actin), Western Blot (ZO-1, ?-actin) and immunofluorescence (ZO-1) were performed. Data of at least three independent experiments were analysed with ANOVA and Dunnett's post hoc test. Basolateral DON resulted in significantly lower cell counts (p<0.05) with larger cells (p<0.01), whereas apical DON reduced total (p<0.001) and specific protein content (IL-8 content CON vs. DON: 2378pg/3mL vs. 991 pg/3mL; p<0.001). Transcripts of ß-actin and ZO-1 were significantly upregulated in response to DON, irrespective of direction, whereas IL-8 mRNA remained unaffected. However, ZO-1 spatial distribution in the tight junction and its function (TEER) were detrimentally affected by basolateral DON only. In conclusion, direction of DON exposure affected IPEC-J2 differently on a translational and functional level, but was mainly inconsequential on a transcriptional level. PMID:26417708

  13. Obesity Increases Sensitivity to Endotoxin Liver Injury: Implications for the Pathogenesis of Steatohepatitis

    NASA Astrophysics Data System (ADS)

    Yang, Shi Qi; Zhi Lin, Hui; Lane, M. Daniel; Clemens, Mark; Diehl, Anna Mae

    1997-03-01

    Genetically obese fatty/fatty rats and obese/obese mice exhibit increased sensitivity to endotoxin hepatotoxicity, quickly developing steatohepatitis after exposure to low doses of lipopolysaccharide (LPS). Among obese animals, females are more sensitive to endotoxin liver injury than males. LPS induction of tumor necrosis factor ? (TNF? ), the proven affecter of endotoxin liver injury, is no greater in the livers, white adipose tissues, or sera of obese animals than in those of lean controls. Indeed, the lowest serum concentrations of TNF occur in female obese rodents, which exhibit the most endotoxin-induced liver injury. Several cytokines that modulate the biological activity of TNF are regulated abnormally in the livers of obese animals. After exposure to LPS, mRNA of interferon ? , which sensitizes hepatocytes to TNF toxicity, is overexpressed, and mRNA levels of interleukin 10, a TNF inhibitor, are decreased. The phagocytic activity of liver macrophages and the hepatic expression of a gene encoding a macrophage-specific receptor are also decreased in obesity. This new animal model of obesity-associated liver disease demonstrates that hepatic macrophage dysfunction occurs in obesity and suggests that this might promote steatohepatitis by sensitizing hepatocytes to endotoxin.

  14. High in vitro immune reactivity to Escherichia coli in neuromyelitis optica patients is correlated with both neurological disabilities and elevated plasma lipopolysaccharide levels.

    PubMed

    Barros, Priscila O; Linhares, Ulisses C; Teixeira, Bruna; Kasahara, Taissa M; Ferreira, Thais B; Alvarenga, Regina; Hygino, Joana; Silva-Filho, Renato G; Bittencourt, Vera Carolina B; Andrade, Regis M; Andrade, Arnaldo F; Bento, Cleonice A M

    2013-09-01

    The pathogenesis of neuromyelitis optica (NMO) is influenced by a combination of genetic and environmental factors, including infectious agents. Several infectious diseases can both trigger or exacerbate autoimmunity. The objective of the present work was to evaluate the in vitro immune responsiveness to Escherichia coli (EC), Staphylococcus aureus (SA) and Candida albicans (CA) in remittent-recurrent NMO patients, and correlate it with the level of neurological disability. Our results revealed that the extent of lymphoproliferation and cytokine profile in response to SA- and CA-stimulated PBMC cultures was similar between NMO patients and healthy individuals. Nevertheless, a higher in vitro CD4(+) T cell proliferation associated with elevated IL-1?, IL-6 and IL-17 release was observed in NMO-derived EC-stimulated cell cultures. Additionally, in these last cultures, the IL-10 production was significantly lower as compared with control group. The in vitro EC-induced levels of IL-6 and IL-17 were positively related with neurological disabilities. This higher tendency to produce Th17-related cytokines was proportional to the production of IL-23 and IL-6 by LPS-activated monocytes. Interestingly, elevated LPS levels were quantified in the plasma of NMO patients. The results suggest that a higher Th17-responsiveness to E. coli could be involved in the NMO pathogenesis. PMID:23777933

  15. Endotoxin induces fibrosis in vascular endothelial cells through a mechanism dependent on transient receptor protein melastatin 7 activity.

    PubMed

    Echeverría, Cesar; Montorfano, Ignacio; Hermosilla, Tamara; Armisén, Ricardo; Velásquez, Luis A; Cabello-Verrugio, Claudio; Varela, Diego; Simon, Felipe

    2014-01-01

    The pathogenesis of systemic inflammatory diseases, including endotoxemia-derived sepsis syndrome, is characterized by endothelial dysfunction. It has been demonstrated that the endotoxin lipopolysaccharide (LPS) induces the conversion of endothelial cells (ECs) into activated fibroblasts through endothelial-to-mesenchymal transition mechanism. Fibrogenesis is highly dependent on intracellular Ca2+ concentration increases through the participation of calcium channels. However, the specific molecular identity of the calcium channel that mediates the Ca2+ influx during endotoxin-induced endothelial fibrosis is still unknown. Transient receptor potential melastatin 7 (TRPM7) is a calcium channel that is expressed in many cell types, including ECs. TRPM7 is involved in a number of crucial processes such as the conversion of fibroblasts into activated fibroblasts, or myofibroblasts, being responsible for the development of several characteristics of them. However, the role of the TRPM7 ion channel in endotoxin-induced endothelial fibrosis is unknown. Thus, our aim was to study whether the TRPM7 calcium channel participates in endotoxin-induced endothelial fibrosis. Using primary cultures of ECs, we demonstrated that TRPM7 is a crucial protein involved in endotoxin-induced endothelial fibrosis. Suppression of TRPM7 expression protected ECs from the fibrogenic process stimulated by endotoxin. Downregulation of TRPM7 prevented the endotoxin-induced endothelial markers decrease and fibrotic genes increase in ECs. In addition, TRPM7 downregulation abolished the endotoxin-induced increase in ECM proteins in ECs. Furthermore, we showed that intracellular Ca2+ levels were greatly increased upon LPS challenge in a mechanism dependent on TRPM7 expression. These results demonstrate that TRPM7 is a key protein involved in the mechanism underlying endotoxin-induced endothelial fibrosis. PMID:24710004

  16. Endotoxin Induces Fibrosis in Vascular Endothelial Cells through a Mechanism Dependent on Transient Receptor Protein Melastatin 7 Activity

    PubMed Central

    Echeverría, Cesar; Montorfano, Ignacio; Hermosilla, Tamara; Armisén, Ricardo; Velásquez, Luis A.; Cabello-Verrugio, Claudio; Varela, Diego; Simon, Felipe

    2014-01-01

    The pathogenesis of systemic inflammatory diseases, including endotoxemia-derived sepsis syndrome, is characterized by endothelial dysfunction. It has been demonstrated that the endotoxin lipopolysaccharide (LPS) induces the conversion of endothelial cells (ECs) into activated fibroblasts through endothelial­to­mesenchymal transition mechanism. Fibrogenesis is highly dependent on intracellular Ca2+ concentration increases through the participation of calcium channels. However, the specific molecular identity of the calcium channel that mediates the Ca2+ influx during endotoxin-induced endothelial fibrosis is still unknown. Transient receptor potential melastatin 7 (TRPM7) is a calcium channel that is expressed in many cell types, including ECs. TRPM7 is involved in a number of crucial processes such as the conversion of fibroblasts into activated fibroblasts, or myofibroblasts, being responsible for the development of several characteristics of them. However, the role of the TRPM7 ion channel in endotoxin-induced endothelial fibrosis is unknown. Thus, our aim was to study whether the TRPM7 calcium channel participates in endotoxin-induced endothelial fibrosis. Using primary cultures of ECs, we demonstrated that TRPM7 is a crucial protein involved in endotoxin-induced endothelial fibrosis. Suppression of TRPM7 expression protected ECs from the fibrogenic process stimulated by endotoxin. Downregulation of TRPM7 prevented the endotoxin-induced endothelial markers decrease and fibrotic genes increase in ECs. In addition, TRPM7 downregulation abolished the endotoxin-induced increase in ECM proteins in ECs. Furthermore, we showed that intracellular Ca2+ levels were greatly increased upon LPS challenge in a mechanism dependent on TRPM7 expression. These results demonstrate that TRPM7 is a key protein involved in the mechanism underlying endotoxin-induced endothelial fibrosis. PMID:24710004

  17. Interaction of lipopolysaccharide with a mammalian lyso-phosphatidate acyltransferase (LPAAT) transfected into E. coli, and effect of lisofylline on LPAAT transfected into mammalian cells.

    PubMed

    Bursten, S L

    1998-01-01

    1. Lipid A and LPS stimulate LPAAT activity (and hence unsaturated PA formation) in RMC membranes and whole cells. 2. This correlates with cell phenotypic and membrane changes associated with small G proteins. 3. Unsaturated PA and Lipid A have similar effects on cells when given exogenously. 4. Human LPAAT-alpha and -beta isoforms were cloned and transfected into E. coli, demonstrating the ability to restore PA synthesis and reduce lyso-PA accumulation in plsC strains (LPAAT deficient mutants), as well as restoring growth at high temperatures. 5. LPAAT transfection into E. coli plsC (JC201) strains results in an increase in LPS content, suggesting stimulation of LPS synthesis. 6. LPAAT transfection into human A549 lung epithelial carcinoma and endothelial ECV304 cells results in increased cytokine mRNA transcription at baseline, and a significant increase in stimulated cytokine mRNA transcription. In addition, LPAAT transfection also results in increased cytokine release in response to IL-1 beta. 7. LSF, which reduces rodent deaths in sepsis models, reduces unsaturated acyl incorporation into PA in monoblastic cell lines, and reduces serum FFA increase in human sepsis, also reduces unsaturated acyl incorporation into PA in ECV304 cells. LPAAT-alpha transfection increases linolenate incorporation into PA at the expense of linoleate incorporation, which is reversed by LSF. LPAAT-beta increases both linoleate and linolenate incorporation into PA, which is also reduced by LSF. We conclude that LPAAT and PA remodeling may play a role in diffuse renal toxicity in sepsis due to induction of cellular phenotype changes associated with PA induction by Lipid A and/or LPS. Two human isoforms of LPAAT have been cloned, and apparently address C18 unsaturated acyl chains somewhat selectively. LSF causes functional reduction in LPAAT activity in transfected systems. This does not yet imply a direct effect of LSF on LPAAT. LPAAT and LPS may interact in the membrane in a not-yet-understood manner. PMID:9575575

  18. Amelioration of endotoxin-induced uveitis treated with the sea urchin pigment echinochrome in rats

    PubMed Central

    Kitaichi, Nobuyoshi; Noda, Kousuke; Mizuuchi, Kazuomi; Ando, Ryo; Dong, Zhenyu; Fukuhara, Junichi; Kinoshita, Satoshi; Namba, Kenichi; Ohno, Shigeaki; Ishida, Susumu

    2014-01-01

    Purpose Echinochrome is a pigment present in the shells and spines of sea urchins. It has been reported to have several biologic protective effects, including in experimental models of myocardial ischemia/reperfusion injury, for which the proposed mechanisms are scavenging reactive oxygen species (ROS) and chelating iron. Endotoxin-induced uveitis (EIU) is an animal model of acute anterior segment intraocular inflammation that is induced by the injection of lipopolysaccharide (LPS). In this study, the therapeutic effect of echinochrome was examined in uveitis using the EIU model. Methods EIU was induced in Lewis rats via 200 ?g subcutaneous injections of LPS from Escherichia coli. Echinochrome was administered intravenously in 10, 1, or 0.1 mg/kg doses suspended in PBS (controls were injected with PBS only). Twenty-four hours after LPS injection, the number of infiltrating cells and the protein concentration in aqueous humor were determined. Aqueous tumor necrosis factor ? (TNF-?) concentration was quantified with enzyme-linked immunosorbent assay, eyes were stained with nuclear factor (NF) ?B antibodies, and ROS production was determined by dihydroethidium staining in fresh frozen samples. Results The number of inflammatory aqueous cells and protein levels were lower in the groups treated with 10 and 1 mg/kg of echinochrome than in the untreated LPS group (p<0.01). Treatment with 10 and 1 mg/kg of echinochrome significantly reduced TNF-? concentrations in aqueous humor (p<0.01). The numbers of NF?B-positive cells and ROS signals were also reduced by echinochrome administration (p<0.05). Conclusions Echinochrome ameliorated intraocular inflammation caused by EIU by reducing ROS production, thereby also decreasing the expression of NF?B and TNF-?. As a natural pigment, echinochrome may therefore be a promising candidate for the safe treatment of intraocular inflammation. The use of sea urchin shells and spines in health foods and medical products is thus both economically and environmentally meaningful. PMID:24520186

  19. Effect of endotoxin on lipid peroxidation in vivo in selenium and vitamin E deficient rats

    SciTech Connect

    Sword, J.T.; Pope, A.L.; Hoekstra, W.G.

    1986-03-01

    The authors have used respiratory ethane production by selenium (Se) and vitamin E (E) deficient rats, an index of lipid peroxidation, to identify oxidant stressors which might precipitate sudden tissue degeneration in deficient animals. Other studies have suggested that endotoxin (gram-negative bacterial lipopolysaccharide-LPS) might be such an oxidant stressor, especially in the lungs. Male weanling rats were fed a Se and E deficient diet for about 80 days. Rats were injected ip with Salmonella typhimurium LPS (.25, .5, or 1.0 mg/kg) or saline, and respiratory ethane was collected for 16 hr. In a representative experiment, mean rate of ethane production (nm/100g/hr) was increased (p < .01) by LPS: saline, .48 +/- .04 (SEM); .25 mg LPS/kg, 1.30 +/- .17; .5, 1.47 +/- .18 and 1.0, 1.68 +/- .18. E. coli and S. minnesota LPS gave similar results. Rats fed a supplemented diet (.2 ppm Se and 200 IU E/kg diet) produced less (p < .01) ethane: saline, .068 +/- .009 and .5 mg LPS/kg, .114 +/- .01. Over all experiments LPS produced a small yet significant increase in ethane in rats receiving Se or E supplementation but produced a marked increase in unsupplemented rats. In further studies with LPS treated rats, Se supplementation alone was 73%, and E supplementation alone 99% as effective as Se + E. These results showed that LPS stimulates lipid peroxidation in Se and E deficient rats and that infections may initiate oxidative cell damage in deficient animals. E was more protective than Se against LPS-induced peroxidation.

  20. A rapid assay of endotoxin in whole blood using autologous neutrophil dependent chemiluminescence.

    PubMed

    Romaschin, A D; Harris, D M; Ribeiro, M B; Paice, J; Foster, D M; Walker, P M; Marshall, J C

    1998-03-15

    A rapid (30 min) whole blood assay for the detection of lipopolysaccharide (LPS) is described. This chemiluminescent (CL) assay utilizes the CR1 and CR3 receptor-induced oxidant production of polymorphonuclear leucocytes as a detection platform. The differential priming of neutrophils in whole blood by LPS-antibody complexes allows the specificity of the assay to be achieved. Oxidant released in response to complement opsonized zymosan results in luminol oxidation and subsequent light emission. This is dependent on heat labile putative complement proteins in the plasma. The assay consists of a control which measures baseline whole blood neutrophil oxidant production. The test assay contains murine monoclonal IgM antibody against the Lipid A epitope of LPS and measures the enhanced chemiluminescent response of the neutrophils in the presence of LPS-antibody complexes. Maximal sensitivity of the CL assay is dependent upon optimal antigen-antibody equivalence and duration of pre-incubation with the whole blood sample. The quantification of LPS is possible by inclusion of a positive control containing a maximally reactive LPS dose (800 pg/ml Escherichia coli 055:B5 LPS at an antibody concentration of 0.8 microg/assay). The CL assay is insensitive to variations in patient neutrophil concentration over a minimum range of 0.5 to 20 x 10(9) cells/l. The CL assay is widely reactive with the LPS of many strains of gram negative bacteria but not with the cell wall products of gram positive bacteria or Candida and Aspergillus. In comparison to acid extraction chromogenic LAL, the CL assay demonstrates superior recovery precision and accuracy in in vitro studies. This was reproducible over a wide range of LPS concentrations (0.017-1.6 EU/ml or 20-2000 pg/ml). This assay may be a clinically useful tool for the diagnosis of infection or endotoxin in patients. PMID:9672205

  1. SUBCHRONIC ENDOTOXIN INHALATION CAUSES PERSISTENT AIRWAY DISEASE

    EPA Science Inventory

    ABSTRACT

    The endotoxin component of organic dusts causes acute reversible airflow obstruction and airway inflammation. To test the hypothesis that endotoxin alone causes airway remodeling, we have compared the response of two inbred mouse strains to subchronic endotoxin ...

  2. 21 CFR 866.3210 - Endotoxin assay.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Endotoxin assay. 866.3210 Section 866.3210 Food... DEVICES IMMUNOLOGY AND MICROBIOLOGY DEVICES Serological Reagents § 866.3210 Endotoxin assay. (a) Identification. An endotoxin assay is a device that uses serological techniques in whole blood. The device...

  3. Endotoxin Studies And Biosolids Stabilization Research

    EPA Science Inventory

    This presentation has three parts; a review of bench-scale endotoxin research, a review of observations from a field scale endotoxin release study, and discussion of biosolids stabilization and characterization by PLFA/FAME microbial community analysis. Endotoxins are part of th...

  4. Plasma endotoxin in typhoid fever.

    PubMed

    Suyasa, I G; Reka, I G; Inada, K; Suda, H; Kojima, M; Mushiaki, K; Okamoto, S; Yoshida, M

    1995-10-01

    Plasma endotoxin contents of the patients with sepsis or typhoid fever were measured by two sophisticated chromogenic limulus tests; Endospecy and Toxicolor tests. Endospecy test is the endotoxin-specific test and Toxicolor is responsible for both endotoxin and (1,3)-beta-D-glucan. Plasma was pretreated by our new PCA method which resolved the problem as to the detection of a lesser amount of plasma endotoxin when pretreated by the conventional PCA method. Although Toxicolor values have been reported to exceed more than the Endospecy value, under complicated pathophysiological situations, almost all specimens of these patients had a similar value, except in one expired septic shock case. In 18 typhoid fever cases, Salmonella typhi was isolated only from the bile in 5 cases, however endotoxemia occurred in 11 cases (61.1%). Within the first 4 days, the incidence of endotoxemia was higher (10/14, 71.4%). These results suggest that endotoxin assay seemed to be a useful tool for the diagnosis of typhoid fever. PMID:8929638

  5. Lipopolysaccharide Phosphorylation by the WaaY Kinase Affects the Susceptibility of Escherichia coli to the Human Antimicrobial Peptide LL-37.

    PubMed

    Bociek, Karol; Ferluga, Sara; Mardirossian, Mario; Benincasa, Monica; Tossi, Alessandro; Gennaro, Renato; Scocchi, Marco

    2015-08-01

    The human cathelicidin LL-37 is a multifunctional host defense peptide with immunomodulatory and antimicrobial roles. It kills bacteria primarily by altering membrane barrier properties, although the exact sequence of events leading to cell lysis has not yet been completely elucidated. Random insertion mutagenesis allowed isolation of Escherichia coli mutants with altered susceptibility to LL-37, pointing to factors potentially relevant to its activity. Among these, inactivation of the waaY gene, encoding a kinase responsible for heptose II phosphorylation in the LPS inner core, leads to a phenotype with decreased susceptibility to LL-37, stemming from a reduced amount of peptide binding to the surface of the cells, and a diminished capacity to lyse membranes. This points to a specific role of the LPS inner core in guiding LL-37 to the surface of Gram-negative bacteria. Although electrostatic interactions are clearly relevant, the susceptibility of the waaY mutant to other cationic helical cathelicidins was unaffected, indicating that particular structural features or LL-37 play a role in this interaction. PMID:26100635

  6. Experimental Study on Inactivation of Bacterial Endotoxin by Using Dielectric Barrier Discharge

    NASA Astrophysics Data System (ADS)

    Shi, Xingmin; Li, Yaxi; Zhang, Guanjun; Ma, Yue; Shao, Xianjun

    2011-12-01

    The low-temperature plasma (LTP) generated by dielectric barrier discharge (DBD) was used to sterilize the E.coli endotoxin, which is usually difficult to kill by traditional methods. Three different concentrations of bacterial endotoxin (1 EU/mL, 0.5 EU/mL and 0.25 EU/mL) were treated by LTP for different time (20 s, 40 s and 60 s). Tachypleus amebocyte lysate (TAL) method was employed to detect the concentration variation of bacterial endotoxin before and after the plasma treatment, and endotoxic shock mice model was used to evaluate the inactivation effects of LTP on endotoxin for further study. Experimental results demonstrated that, DBD plasma can inactivate the bacterial endotoxin quickly and effectively, and when the LTP treatment time was increased, the concentrations of bacterial endotoxin decreased gradually (after 60 s plasma treatment, its inactivation effect was beyond the Chinese pharmacopoeia standard), and the average survival time of mice gradually extended. The possible inactivation mechanisms are proposed to be related to reactive oxygen species (ROSs).

  7. Comparison of Different Irrigants in the Removal of Endotoxins and Cultivable Microorganisms from Infected Root Canals

    PubMed Central

    Valera, Marcia Carneiro; Cardoso, Flávia Goulart da Rosa; Chung, Adriana; Xavier, Ana Cláudia Carvalho; Figueiredo, Mariana Diehl; Martinho, Frederico Canato; Palo, Renato Miotto

    2015-01-01

    This study was conducted to compare the effectiveness of different irrigants used to remove endotoxins and cultivable microorganisms during endodontic therapy. Forty root canals were contaminated and divided into groups according to the irrigant: 2% NaOCl + surfactant, 2% CHX, 2.5% NaOCl, and pyrogen-free saline solution (control). Samples were collected after root canal contamination (S1), after instrumentation (S2), and 7 days after instrumentation (S3). Microorganisms and endotoxins were recovered from 100% of the contaminated root canals (S1). At S2, 2% NaOCl + surfactant, 2% CHX, and 2.5% NaOCl were able to completely eliminate cultivable microorganisms. At S3, both 2% CHX and 2.5% NaOCl were effective in preventing C. albicans and E. coli regrowth, but E. faecalis was still detected. No microorganism species was recovered from root canals instrumented with 2% NaOCl + surfactant. At S2, a higher percentage value of endotoxin reduction was found for 2% NaOCl + surfactant (99.3%) compared to 2% CHX (98.9%) and 2.5% NaOCl (97.18%) (p < 0.05). Moreover, at S3, 2% NaOCl + surfactant (100%) was the most effective irrigant against endotoxins. All irrigants tested were effective in reducing microorganisms and endotoxins from root canals. Moreover, 2% NaOCl + surfactant was the most effective irrigant against endotoxins and regrowth of microorganisms. PMID:26346574

  8. Predictors of airborne endotoxin in the home.

    PubMed Central

    Park, J H; Spiegelman, D L; Gold, D R; Burge, H A; Milton, D K

    2001-01-01

    We identified home characteristics associated with the level of airborne endotoxin in 111 Boston-area homes enrolled in a cohort study of home exposures and childhood asthma, and we developed a predictive model to estimate airborne endotoxin. We measured endotoxin in family-room air and in dust from the baby's bed, family room, bedroom, and kitchen floor. Level of airborne endotoxin was weakly correlated (r < 0.3) with level of endotoxin in each of the four types of dust samples and was significantly correlated with endotoxin in family-room dust (p < 0.05). Endotoxin in family-room dust accounted for < 6% of the variability of airborne endotoxin. In a multivariate model, certain home characteristics were positively (p < 0.05) associated with airborne endotoxin. These included current presence of dog (difference in level, dog vs. no dog = 72%, partial R(2 )= 12.8%), past presence of dog (partial R(2) = 5.5%), and endotoxin level in family-room dust (partial R(2) = 5.3%). Use of a dehumidifier (partial R(2) = 6.4%) was negatively associated (p = 0.02; difference = -31%) with airborne endotoxin. Other home characteristics were identified as important determinants of increased airborne endotoxin in this model, but individual coefficients were not statistically significant (alpha = 0.05): total amount of fine dust collected in the home (partial R(2 )= 3.8%), concrete floor in family room (3.7%), water damage (3.6%), and use of cool-mist humidifier in past year (2.7%). This multivariate model explained 42% of the variability of airborne endotoxin levels, a substantial improvement over that with dust endotoxin alone. Airborne endotoxin in Boston-area homes appears to be determined by the presence of dogs, moisture sources, and increased amounts of settled dust. PMID:11564624

  9. Lipopolysaccharide O antigen size distribution is determined by a chain extension complex of variable stoichiometry in Escherichia coli O9a

    PubMed Central

    King, Jerry D.; Berry, Scott; Clarke, Bradley R.; Morris, Richard J.; Whitfield, Chris

    2014-01-01

    The lengths of bacterial polysaccharides can be critical for their biological function. Unlike DNA or protein synthesis, where polymer length is implicit in the nucleic acid template, the molecular mechanisms for regulating polysaccharide length are poorly understood. Two models are commonly cited: a “molecular clock” regulates length by controlling the duration of the polymer extension process, whereas a “molecular ruler” determines length by measurement against a physical structure in the biosynthetic complex. Escherichia coli O9a is a prototype for the biosynthesis of O polysaccharides by ATP-binding cassette transporter-dependent processes. The length of the O9a polysaccharide is determined by two proteins: an extension enzyme, WbdA, and a termination enzyme, WbdD. WbdD is known to self-oligomerize and also to interact with WbdA. Changing either enzyme’s concentration can alter the polysaccharide length. We quantified the O9a polysaccharide length distribution and the enzyme concentration dependence in vivo, then made mathematical models to predict the polymer length distributions resulting from hypothetical length-regulation mechanisms. Our data show qualitative features that cannot be explained by either a molecular clock or a molecular ruler model. Therefore, we propose a “variable geometry” model, in which a postulated biosynthetic WbdA–WbdD complex assembles with variable stoichiometry dependent on relative enzyme concentration. Each stoichiometry produces polymers with a distinct, geometrically determined, modal length. This model reproduces the enzyme concentration dependence and modality of the observed polysaccharide length distributions. Our work highlights limitations of previous models and provides new insight into the mechanisms of length control in polysaccharide biosynthesis. PMID:24733938

  10. Inactivation of endotoxin by polymyxin B.

    PubMed

    Cooperstock, M S

    1974-10-01

    The limulus gelation assay was utilized to investigate endotoxin inactivation by a number of antibiotics in vitro. Endotoxin activity was sharply reduced by polymyxin B and sodium colistimethate. The effect of the polymyxin was not significantly inhibited by 0.001 M calcium or 90% serum. Crude endotoxins from a variety of aerobic gram-negative bacteria, including several not previously studied, could be inactivated 1 or more logs by as little as 1 mug of polymyxin B per ml, whereas Bacteroides fragilis endotoxin was poorly detoxified. A 10,000-fold range in the relative susceptibility of different endotoxins to inactivation by polymyxin B was found. The endotoxin most susceptible to polymyxin B was derived from an organism resistant to polymyxin B by disk sensitivity testing, suggesting that the bacteriocidal and endotoxin detoxifying properties of polymyxin need not be directly related. PMID:4157338

  11. Endotoxin markers in bronchoalveolar lavage fluid of patients with interstitial lung diseases

    PubMed Central

    2012-01-01

    Background Exposure to inhaled endotoxins (lipopolysaccharides, LPS) of Gram-negative bacteria commonly found in indoor environments and assessed in secondary tobacco smoke, has been associated with airway inflammation and asthma exacerbation. The bronchoalveolar lavage fluid (BALf) from patients with interstitial lung diseases (sarcoidosis, lung fibrosis, smoking-related ILD, eosinophilic disorders) was analyzed for the markers of lipopolysaccharide (LPS, endotoxin). Methods BALf was obtained from patients with diffuse lung diseases: idiopathic pulmonary fibrosis (n = 42), sarcoidosis (n = 22), smoking-related-ILD (n = 11) and eosinophilic disorders (n = 8). Total cell count and differential cell count were performed. In addition, samples were analyzed for 3-hydroxy fatty acids (3-OHFAs) of 10–18 carbon chain lengths, as markers of LPS, by gas chromatography-tandem mass spectrometry. Results The highest LPS concentration was found in patients with eosinophilic disorders and the lowest in patients with sarcoidosis (p< 0.05) followed by the lung fibrosis and the sr-ILD patients. The difference between LPS in BALf with extremely high eosinophil proportion (> 25%) and those with lower proportion was also significant (p = 0.014). A significant correlation was found between LPS and eosinophils, but not between LPS and lymphocytes, neutrophils, or macrophages count. Conclusions A positive relationship of LPS and eosinophilic pulmonary disorders may be linked to a persistent eosinophil activation mediated by Th2 pathway: chronic endotoxin exposure would intensify Th2 pathway resulting in fibrosis and, at the same time, eosinophil stimulation, and hence in eosinophilic pulmonary disorders. PMID:23259971

  12. Escherichia coli morphological changes and lipid A removal induced by reduced pressure nitrogen afterglow exposure.

    PubMed

    Zerrouki, Hayat; Rizzati, Virginie; Bernis, Corinne; Nègre-Salvayre, Anne; Sarrette, Jean Philippe; Cousty, Sarah

    2015-01-01

    Lipid A is a major hydrophobic component of lipopolysaccharides (endotoxin) present in the membrane of most Gram-negative bacteria, and the major responsible for the bioactivity and toxicity of the endotoxin. Previous studies have demonstrated that the late afterglow region of flowing post-discharges at reduced pressure (1-20 Torr) can be used for the sterilization of surfaces and of the reusable medical instrumentation. In the present paper, we show that the antibacterial activity of a pure nitrogen afterglow can essentially be attributed to the large concentrations of nitrogen atoms present in the treatment area and not to the UV radiation of the afterglow. In parallel, the time variation of the inactivation efficiency quantified by the log reduction of the initial Escherichia coli (E. coli) population is correlated with morphologic changes observed on the bacteria by scanning electron microscopy (SEM) for increasing afterglow exposure times. The effect of the afterglow exposure is also studied on pure lipid A and on lipid A extracted from exposed E. coli bacteria. We report that more than 60% of lipid A (pure or bacteria-extracted) are lost with the used operating conditions (nitrogen flow QN2 = 1 standard liter per minute (slpm), pressure p = 5 Torr, microwave injected power PMW = 200 W, exposure time: 40 minutes). The afterglow exposure also results in a reduction of the lipid A proinflammatory activity, assessed by the net decrease of the redox-sensitive NF?B transcription factor nuclear translocation in murine aortic endothelial cells stimulated with control vs afterglow-treated (pure and extracted) lipid A. Altogether these results point out the ability of reduced pressure nitrogen afterglows to neutralize the cytotoxic components in Gram-negative bacteria. PMID:25837580

  13. Escherichia coli Morphological Changes and Lipid A Removal Induced by Reduced Pressure Nitrogen Afterglow Exposure

    PubMed Central

    Zerrouki, Hayat; Rizzati, Virginie; Bernis, Corinne; Nègre-Salvayre, Anne; Sarrette, Jean Philippe; Cousty, Sarah

    2015-01-01

    Lipid A is a major hydrophobic component of lipopolysaccharides (endotoxin) present in the membrane of most Gram-negative bacteria, and the major responsible for the bioactivity and toxicity of the endotoxin. Previous studies have demonstrated that the late afterglow region of flowing post-discharges at reduced pressure (1-20 Torr) can be used for the sterilization of surfaces and of the reusable medical instrumentation. In the present paper, we show that the antibacterial activity of a pure nitrogen afterglow can essentially be attributed to the large concentrations of nitrogen atoms present in the treatment area and not to the UV radiation of the afterglow. In parallel, the time variation of the inactivation efficiency quantified by the log reduction of the initial Escherichia coli (E. coli) population is correlated with morphologic changes observed on the bacteria by scanning electron microscopy (SEM) for increasing afterglow exposure times. The effect of the afterglow exposure is also studied on pure lipid A and on lipid A extracted from exposed E. coli bacteria. We report that more than 60% of lipid A (pure or bacteria-extracted) are lost with the used operating conditions (nitrogen flow QN2 = 1 standard liter per minute (slpm), pressure p = 5 Torr, microwave injected power PMW = 200 W, exposure time: 40 minutes). The afterglow exposure also results in a reduction of the lipid A proinflammatory activity, assessed by the net decrease of the redox-sensitive NF?B transcription factor nuclear translocation in murine aortic endothelial cells stimulated with control vs afterglow-treated (pure and extracted) lipid A. Altogether these results point out the ability of reduced pressure nitrogen afterglows to neutralize the cytotoxic components in Gram-negative bacteria. PMID:25837580

  14. Immobilization of ?-polylysine onto the probe surface for molecular adsorption type endotoxin detection system

    NASA Astrophysics Data System (ADS)

    Ooe, Katsutoshi; Tsuji, Akihito; Nishishita, Naoki; Hirano, Yoshiaki

    2007-04-01

    Patients with renal failure become not able to expel the waste product, and they accumulate the toxic products for themselves. They therefore must use the hemodialysis to weed out the metabolic decomposition product. Hemodialysis for chronic renal failure is the most popular treatment method with artificial organs. However, hemodialysis patients must continue the treatment throughout their life, the results of long term extracorporeal dialysis, those patients develop the various complications and diseases, for example, dialysis amyloidosis etc. Dialysis amyloidosis is one of the refractory complications, and the prevention of this complication is important. Recently, endotoxin is thought to be the most likely cause of the complication. Endotoxin is one of the major cell wall components of gram-negative bacteria, and it forms the complex with proteins and lipopolysaccharide (LPS). It has various biological activities, e.g. attack of fever, when it gets mixed into human blood. In addition, it is known that large amount of endotoxin exists in living environment, and medicine is often contaminated with endotoxin. When contaminated dialyzing fluids are used to hemodialysis, above-mentioned dialysis amyloidosis is developed. Therefore, it is important that the detection and removal of endotoxin from dialyzing fluids. Until now, the measurement methods using Limulus Amebosyte Lysate (LAL) reagent were carried out as the tests for the presence of endotoxin. However, these methods include several different varieties of measurement techniques. The following are examples of them, gelatinization method, turbidimetric assay method, colorimetric assay method and fluoroscopic method. However, these techniques needed 30-60 minutes for the measurement. From these facts, they are not able to use as a "real-time endotoxin detector". The detection of endotoxin has needed to carry out immediately, for that reason, a new "real-time" detection method is desired. We focused attention to adsorption reaction between ?-polylysine and endotoxin. ?-polylysine has the structure of straight chain molecule composed by 25-30 residues made by lysine, and it is used as an antimicrobial agent, moreover, cellulose beads with immobilized ?-polylysine is used as the barrier filter for endotoxin removal. Therefore, it is expected that the endotoxin be adsorbed to the immobilized ?-polylysine onto the probe. As the result of this reaction, the mass of the probe is increased, and endotoxin can be detected by using of Quartz Crystal Microbalance (QCM). In our previous research, we have already acquired the proteins immobilization technique onto Au and Si surface. In this report, the proposal of molecular adsorption type endotoxin detection system, and the immobilization of ?-polylysine onto the probe are described. We use X-ray Photoelectron Spectroscopy (XPS) to confirm the ?-polylysine immobilization, and the adsorptive activity of immobilized ?-polylysine is measured by XPS and AFM. The purpose of this study is to bring about the realization of "Real-time endotoxin detection system".

  15. Investigation of adrenergic and prostaglandin influences in the endotoxin alteration of hepatic heme oxygenase, microsomal mixed-function oxidase, and glucocorticoid-induced tryptophan oxygenase activities.

    PubMed

    Williams, J F; Szentivanyi, A

    1983-08-01

    The possible role for adrenergic influences or prostaglandins in the effects of endotoxin to inhibit the glucocorticoid induction of hepatic tryptophan oxygenase (TO) activity, to decrease the hepatic microsomal cytochrome P--450-dependent drug-metabolizing activity, and to induce heme oxygenase activity was examined. Administration of the alpha-adrenergic locking agents phenoxybenzamine or phentolamine attenuated the inhibitory effect of the bacterial lipopolysaccharide on the induction of TO activity by dexamethasone. Injection of a beta-adrenergic blocker, propranolol, or of indomethacin, an inhibitor of prostaglandin biosynthesis, accentuated the effect of endotoxin to inhibit TO induction. Neither phenoxybenzamine, propranolol, nor indomethacin altered the effect of endotoxin to decrease aniline hydroxylase activity, ethylmorphine N-demethylase activity, or the levels of cytochrome P--450. Also, dexamethasone administration did not significantly protect against the effects of endotoxin on the hepatic microsomal drug metabolizing enzyme system, and none of the pharmacological agents diminished the effects of endotoxin to induce hepatic heme oxygenase activity. Endotoxin administration was also shown to diminish, but not prevent, the induction of cytochrome P--450 and ethylmorphine N-demethylase activity produced by phenobarbital. The results indicate that alpha-adrenergic mechanisms are involved in the endotoxic inhibition of the glucocorticoid induction of TO activity and suggest that neither adrenergic influences nor prostaglandins play a significant role in the effect of endotoxin to decrease hepatic mixed-function oxidase activity. PMID:6136493

  16. Piceatannol Suppresses endotoxin-induced ocular inflammation in Rats

    PubMed Central

    Kalariya, Nilesh M.; Shoeb, Mohammad; Reddy, Aramati B. M.; Sawhney, Rahul; Ramana, Kota V.

    2013-01-01

    Anti-inflammatory effect of piceatannol, a naturally occurring polyphenol and a potent free radical scavenger, on ocular inflammation is not known. We examined the anti-inflammatory role of piceatannol in ocular inflammatory response due to endotoxin-induced uveitis (EIU) in rats. EIU was induced in Lewis rats by subcutaneous injection of lipopolysaccharide (LPS; 150 ug/rat). Piceatannol (30 mg/kg body wt, i.p) was injected either 2 h prior to or 1 h post LPS induction. A significant increase in the number of infiltrating cells, total protein, and various cytokines and chemokines in AqH were observed in the EIU rat eyes as compared to control groups. However, pre- or post- treatment of piceatannol significantly blocked the LPS-induced changes. Further, piceatannol also suppressed the expression of Cox-2, iNOS and activation of NF-?B in the ciliary bodies as well as retina. Further, piceatannol also inhibited the expression of Cox-2, iNOS, and phosphorylation of NF-?B in primary human non-pigmented ciliary epithelial cells (HNPECs) treated with LPS. Similarly, piceatannol also diminished LPS-induced level of NO and PGE2 in HNPECs. Thus our results demonstrate an anti-inflammatory role of piceatannol in suppressing ocular inflammation induced by endotoxin in rats. PMID:23892029

  17. Piceatannol suppresses endotoxin-induced ocular inflammation in rats.

    PubMed

    Kalariya, Nilesh M; Shoeb, Mohammad; Reddy, Aramati B M; Sawhney, Rahul; Ramana, Kota V

    2013-10-01

    Anti-inflammatory effect of piceatannol, a naturally occurring polyphenol and a potent free radical scavenger, on ocular inflammation is not known. We examined the anti-inflammatory role of piceatannol in ocular inflammatory response due to endotoxin-induced uveitis (EIU) in rats. EIU was induced in Lewis rats by subcutaneous injection of lipopolysaccharide (LPS; 150 ug/rat). Piceatannol (30mg/kg body wt, i.p) was injected either 2h prior to or 1h post LPS induction. A significant increase in the number of infiltrating cells, total protein, and various cytokines and chemokines in AqH were observed in the EIU rat eyes as compared to control groups. However, pre- or post-treatment of piceatannol significantly blocked the LPS-induced changes. Further, piceatannol also suppressed the expression of cyclooxygenase-2 (Cox-2), inducible nitric oxide synthase (iNOS) and activation of NF-?B in the ciliary bodies as well as retina. Further, piceatannol also inhibited the expression of Cox-2, iNOS, and phosphorylation of NF-?B in primary human non-pigmented ciliary epithelial cells (HNPECs) treated with LPS. Similarly, piceatannol also diminished LPS-induced level of NO and prostaglandin E2 in HNPECs. Thus our results demonstrate an anti-inflammatory role of piceatannol in suppressing ocular inflammation induced by endotoxin in rats. PMID:23892029

  18. Protection from Oxygen Toxicity with Endotoxin

    PubMed Central

    Frank, L.; Summerville, J.; Massaro, D.

    1980-01-01

    Endotoxin treatment of adult rats before hyperoxic exposure significantly increases their survival rate in >95% O2 (J. Clin. Invest.61: 269, 1978). In this study, we wished to determine: (a) whether endotoxin would protect against O2 toxicity if it were administered after the animals were already in >95% O2 for 12-48 h; and (b) the relationship between the endogenous antioxidant enzymes of the lung and the protective effect of endotoxin treatment. Our results showed that adult rats given a single 500 ?g/kg dose of endotoxin up to 36 h after the onset of O2 exposure had significantly increased survival rates and decreased lung fluid accumulation compared to untreated animals in O2 (P < 0.05). (Survival, 16/49 [untreated rats]; 18/20 [endotoxin at 12 h after the start of O2 exposure]; 25/26 [endotoxin-24 h]; 15/20 [endotoxin-36 h].) Endotoxin-treated animals in O2 showed increases in pulmonary superoxide dismutase, catalase, and glutathione peroxidase activities before the usual time of onset of measurable pulmonary edema in untreated animals in O2. When diethyldithiocarbamate was used to block the superoxide dismutase enzyme rise in the endotoxin-treated rats in O2, the protective action of endotoxin against pulmonary O2 toxicity was nullified. In endotoxin-treated, O2-exposed mice, there were no lung antioxidant enzyme increases, and no protective effect from O2 toxicity was achieved. We conclude that, in the rat, a single dose of endotoxin given even 36 h after the onset of hyperoxic exposure results in marked protection against O2-induced lung damage; and the increased lung antioxidant enzyme activity in the endotoxin-treated rats appears to be an essential component of this protective action. PMID:6245106

  19. Mifepristone (RU486) restores humoral and T cell-mediated immune response in endotoxin immunosuppressed mice.

    PubMed

    Rearte, B; Maglioco, A; Balboa, L; Bruzzo, J; Landoni, V I; Laborde, E A; Chiarella, P; Ruggiero, R A; Fernández, G C; Isturiz, M A

    2010-12-01

    Sepsis and septic shock can be caused by Gram-positive and -negative bacteria and other microorganisms. In the case of Gram-negative bacteria, endotoxin, a normal constituent of the bacterial wall, also known as lipopolysaccharide (LPS), has been considered as one of the principal agents causing the undesirable effects in this critical illness. The response to LPS involves a rapid secretion of proinflammatory cytokines such as tumour necrosis factor (TNF)-?, interleukin (IL)-1, IL-6, interferon (IFN)-? and the concomitant induction of anti-inflammatory mediators such as IL-10, transforming growth factor (TGF)-? or glucocorticoids, which render the host temporarily refractory to subsequent lethal doses of LPS challenge in a process known as LPS or endotoxin tolerance. Although protective from the development of sepsis or systemic inflammation, endotoxin tolerance has also been pointed out as the main cause of the non-specific humoral and cellular immunosuppression described in these patients. In this report we demonstrate, using a mouse model, that mifepristone (RU486), a known glucocorticoid receptor antagonist, could play an important role in the restoration of both adaptive humoral and cellular immune response in LPS immunosuppressed mice, suggesting the involvement of endogenous glucocorticoids in this phenomenon. On the other hand, using cyclophosphamide and gemcitabine, we demonstrated that regulatory/suppressor CD4(+) CD25(+) forkhead boxP3(+) and GR-1(+) CD11b(+) cells do not play a major role in the establishment or the maintenance of endotoxin tolerance, a central mechanism for inducing an immunosuppression state. PMID:20964639

  20. Sufficient production of geranylgeraniol is required to maintain endotoxin tolerance in macrophages

    PubMed Central

    Kim, Jinyong; Lee, Joon No; Ye, James; Hao, Rosy; DeBose-Boyd, Russell; Ye, Jin

    2013-01-01

    Endotoxin tolerance allows macrophages to produce large quantities of proinflammatory cytokines immediately after their contact with lipopolysaccharides (LPSs), but prevents their further production after repeated exposure to LPSs. While this response is known to prevent overproduction of proinflammatory cytokines, the mechanism through which endotoxin tolerance is established has not been identified. In the current study, we demonstrate that sufficient production of geranylgeraniol (GGOH) in macrophages is required to maintain endotoxin tolerance. We show that increased synthesis of 3-hydroxy-3-methyl-glutaryl-CoA reductase (HMGCR) protein following LPS treatment is required to produce enough GGOH to inhibit expression of Malt1, a protein known to stimulate expression of proinflammatory cytokines, in macrophages repeatedly exposed to LPSs. Depletion of GGOH caused by inhibition of HMGCR led to increased Malt1 expression in macrophages subjected to repeated exposure to LPSs. Consequently, endotoxin tolerance was impaired, and production of interleukin 1-? and other proinflammatory cytokines was markedly elevated in these cells. These results suggest that insufficient production of GGOH in macrophages may cause autoinflammatory diseases. PMID:24062519

  1. Bench-to-bedside review: Clinical experience with the endotoxin activity assay.

    PubMed

    Romaschin, Alexander D; Klein, David J; Marshall, John C

    2012-01-01

    Endotoxin detection in human patients has been a difficult challenge, in part due to the fact that the conserved active portion of the molecule (lipid A) is a relatively small epitope only amenable to binding by a single ligand at any one instance and low levels (pg/ml) are capable of stimulating the immune system. The endotoxin activity assay, a bioassay based on neutrophil activation by complement opsonized immune complexes of lipopolysaccharide (LPS), has allowed the specific detection of the lipid A epitope of LPS in a rapid whole blood assay format. This review summarizes diagnostic studies utilizing the endotoxin activity assay in a variety of hospital patient populations in whom endotoxin is postulated to play a significant role in disease etiology. These include ICU patients at risk of developing 'sepsis syndrome', abdominal and cardiovascular surgery patients and patients with serious traumatic injury. Significant features of these studies include the high negative predictive value of the assay (98.6%) for rule out of Gram-negative infection, ability to risk stratify patients progressing to severe sepsis (odds ratio 3.0) and evidence of LPS release in patients with gut hypoperfusion. Preliminary studies have successfully combined the assay with anti-LPS removal strategies to prospectively identify patients who might benefit from this therapy with early evidence of clinical benefit. PMID:23206992

  2. Inhibition of lipopolysaccharide induced acute inflammation in lung by chlorination.

    PubMed

    Zhang, Jinshan; Xue, Jinling; Xu, Bi; Xie, Jiani; Qiao, Juan; Lu, Yun

    2016-02-13

    Lipopolysaccharide (LPS, also called endotoxin) is a pro-inflammatory constituent of gram negative bacteria and cyanobacteria, which causes a potential health risk in the process of routine urban application of reclaimed water, such as car wash, irrigation, scenic water refilling, etc. Previous studies indicated that the common disinfection treatment, chlorination, has little effect on endotoxin activity removal measured by Limulus amebocyte lysate (LAL) assay. However, in this study, significant decrease of acute inflammatory effects was observed in mouse lung, while LAL assay still presented a moderate increase of endotoxin activity. To explore the possible mechanisms, the nuclear magnetic resonance (NMR) results showed the chlorination happened in alkyl chain of LPS molecules, which could affect the interaction between LPS and LPS-binding protein. Also the size of LPS aggregates was found to drop significantly after treatment, which could be another results of chlorination caused polarity change. In conclusion, our observation demonstrated that chlorination is effective to reduce the LPS induced inflammation in lung, and it is recommended to use health effect-based methods to assess risk removal of water treatment technologies. PMID:26530889

  3. Inhibition of IRAK-4 activity for rescuing endotoxin LPS-induced septic mortality in mice by lonicerae flos extract

    SciTech Connect

    Park, Sun Hong; Roh, Eunmiri; Kim, Hyun Soo; Baek, Seung-Il; Choi, Nam Song; Kim, Narae; Hwang, Bang Yeon; Han, Sang-Bae; Kim, Youngsoo

    2013-12-13

    Highlights: •Lonicerae flos extract (HS-23) is a clinical candidate, Phase I for sepsis treatment. •Here, HS-23 or its major constituents rescued LPS-induced septic mortality in mice. •As a mechanism, they directly inhibited IRAK-4-catalyzed kinase activity. •Thus, they suppressed LPS-induced expression of NF-?B/AP-1-target inflammatory genes. -- Abstract: Lonicerae flos extract (HS-23) is a clinical candidate currently undergoing Phase I trial in lipopolysaccharide (LPS)-injected healthy human volunteers, but its molecular basis remains to be defined. Here, we investigated protective effects of HS-23 or its major constituents on Escherichia coli LPS-induced septic mortality in mice. Intravenous treatment with HS-23 rescued LPS-intoxicated C57BL/6J mice under septic conditions, and decreased the levels of cytokines such as tumor necrosis factor ? (TNF-?), interleukin (IL)-1? and high-mobility group box-1 (HMGB-1) in the blood. Chlorogenic acid (CGA) and its isomers were assigned as major constituents of HS-23 in the protection against endotoxemia. As a molecular mechanism, HS-23 or CGA isomers inhibited endotoxin LPS-induced autophosphorylation of the IL-1 receptor-associated kinase 4 (IRAK-4) in mouse peritoneal macrophages as well as the kinase activity of IRAK-4 in cell-free reactions. HS-23 consequently suppressed downstream pathways critical for LPS-induced activation of nuclear factor (NF)-?B or activating protein 1 (AP-1) in the peritoneal macrophages. HS-23 also inhibited various toll-like receptor agonists-induced nitric oxide (NO) production, and down-regulated LPS-induced expression of NF-?B/AP-1-target inflammatory genes in the cells. Taken together, HS-23 or CGA isomers exhibited anti-inflammatory therapy against LPS-induced septic mortality in mice, at least in part, mediated through the inhibition of IRAK-4.

  4. 21 CFR 866.3210 - Endotoxin assay.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Endotoxin assay. 866.3210 Section 866.3210 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES IMMUNOLOGY AND MICROBIOLOGY DEVICES Serological Reagents § 866.3210 Endotoxin assay....

  5. 21 CFR 866.3210 - Endotoxin assay.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Endotoxin assay. 866.3210 Section 866.3210 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES IMMUNOLOGY AND MICROBIOLOGY DEVICES Serological Reagents § 866.3210 Endotoxin assay....

  6. 21 CFR 866.3210 - Endotoxin assay.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Endotoxin assay. 866.3210 Section 866.3210 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES IMMUNOLOGY AND MICROBIOLOGY DEVICES Serological Reagents § 866.3210 Endotoxin assay....

  7. 21 CFR 866.3210 - Endotoxin assay.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Endotoxin assay. 866.3210 Section 866.3210 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES IMMUNOLOGY AND MICROBIOLOGY DEVICES Serological Reagents § 866.3210 Endotoxin assay....

  8. Escherichia coli (E. coli)

    MedlinePLUS

    ... Asked Questions Expand All Collapse All What are Escherichia coli ? Escherichia coli (abbreviated as E. coli ) are a large and ... When you hear news reports about outbreaks of “ E. coli ” infections, they are usually talking about E. coli O157. ...

  9. Effects of Propofol and Midazolam on the Inflammation of Lungs after Intravenous Endotoxin Administration in Rats

    PubMed Central

    Celik, Mine Gursac; Saracoglu, Ayten; Saracoglu, Tolga; Kursad, Husnu; Dostbil, Aysenur; Aksoy, Mehmet; Ahiskalioglu, Ali; Ince, Ilker

    2015-01-01

    Objective: Pulmonary complications are important sepsis (such as ARDS, diffuse pneumonia). Acute respiratory distress syndrome (ARDS) is characterized by the extensive migration of neutrophils into alveoli of the lungs. Propofol and midazolam are the most widely used agents for sedation in intensive care units. Aimed to investigate the effects of anaesthesia with propofol and midazolam on measured hemodynamic variables and neutrophil migration induced by Escherichia Coli endotoxin (ECE) in pulmonary viscera. Materials and Methods: Forty Sprague Dawley male rats were randomly assigned to four groups: Thiopental Sodium 30 mg/kg was administered intraperitoneally to anesthetize the rats. They were ventilated via tracheotomy. Femoral artery was cannulated for the measurement of continuous blood pressure and gases. Group C was the control. After the administration of 1 mL/kg 0.9% NaCL, infusion began at 1 mL/kg/h rate. In Group E 15 mg/kg lipopolysaccharide derived from ECE was administered iv. In Group PE, after a bolus dose of 10 mg/kg propofol and 15 mg/kg ECE, 10 mg/kg/h infusion was applied. In Group ME, after 0.1 mg/kg midazolam bolus dose and 15 mg/kg ECE administration, 0.1 mg/kg/h infusion was administered iv. Rats were sacrified by iv potassium chloride. The lungs were then removed, fixed in 10% buffered formalin for 3 days and embedded in paraffin. They were graded on a scale of 0–3 according to the aggregation of neutrophils. Results: There was intense neutrophil migration in Group E (grade 2, 3). However, although mild neutrophil migration was obtained in 70% of the rat lungs in Group ME (grade 1, 2), it was recorded in only 30% of Group PE (grade 1). Conclusion: The sepsis model induced by ECE and compared with midazolam, propofol anaesthesia is associated with less neutrophil infiltration. In the light of the literature, propofol attenuate the free-radical-mediated lipid peroxidation and systemic inflammation in patients. PMID:26180495

  10. Endotoxin-induced changes in IGF-I differ in rats provided enteral vs. parenteral nutrition.

    PubMed

    Wojnar, M M; Fan, J; Li, Y H; Lang, C H

    1999-03-01

    The purpose of the present study was to determine whether acute changes in the insulin-like growth factor (IGF) system induced by mild surgical trauma/fasting or endotoxin [lipopolysaccharide (LPS)] are differentially modulated by total enteral nutrition (TEN) or total parenteral nutrition (TPN). Rats had vascular catheters and a gastrostomy tube surgically placed and were fasted overnight. The next morning animals randomly received an isocaloric, isonitrogenous (250 kcal. kg-1. day-1, 1.6 g N. kg-1. day-1) infusion of either TEN or TPN for 48 h. Then rats were injected intravenously with Escherichia coli LPS (1 mg/kg) while nutritional support was continued. Time-matched control animals were injected with saline. After mild surgical trauma and an 18-h fast, TEN was more effective at increasing plasma IGF-I levels than TPN. Subsequent injection of LPS decreased IGF-I in blood, liver, and muscle in both TEN- and TPN-fed rats compared with saline-injected control animals. However, this decrease was approximately 30% greater in rats fed TPN compared with those fed TEN. LPS-induced downregulation of IGF-I mRNA expression in liver and muscle was also more prominent in TPN-fed rats. The LPS-induced increase in plasma corticosterone and tumor necrosis factor-alpha was greater (2- and 1.6-fold, respectively) in TPN-fed rats, and these changes were consistent with the greater reduction in IGF-I seen in these animals. In similarly treated rats allowed to survive for 24 h after LPS injection, the LPS-induced increase in the urinary 3-methylhistidine-to-creatinine ratio was smaller in TEN-fed rats. In summary, LPS reduced systemic levels of IGF-I as well as IGF-I protein and mRNA in critical target organs. Enteral feeding greatly attenuated this response. Maintenance of higher IGF-I levels in TEN-fed rats was associated with a reduction in inflammatory cytokine levels and lower rates of myofibrillar degradation. PMID:10070010

  11. Super-low Dose Endotoxin Pre-conditioning Exacerbates Sepsis Mortality

    PubMed Central

    Chen, Keqiang; Geng, Shuo; Yuan, Ruoxi; Diao, Na; Upchurch, Zachary; Li, Liwu

    2015-01-01

    Sepsis mortality varies dramatically in individuals of variable immune conditions, with poorly defined mechanisms. This phenomenon complements the hypothesis that innate immunity may adopt rudimentary memory, as demonstrated in vitro with endotoxin priming and tolerance in cultured monocytes. However, previous in vivo studies only examined the protective effect of endotoxin tolerance in the context of sepsis. In sharp contrast, we report herein that pre-conditioning with super-low or low dose endotoxin lipopolysaccharide (LPS) cause strikingly opposite survival outcomes. Mice pre-conditioned with super-low dose LPS experienced severe tissue damage, inflammation, increased bacterial load in circulation, and elevated mortality when they were subjected to cecal-ligation and puncture (CLP). This is in contrast to the well-reported protective phenomenon with CLP mice pre-conditioned with low dose LPS. Mechanistically, we demonstrated that super-low and low dose LPS differentially modulate the formation of neutrophil extracellular trap (NET) in neutrophils. Instead of increased ERK activation and NET formation in neutrophils pre-conditioned with low dose LPS, we observed significantly reduced ERK activation and compromised NET generation in neutrophils pre-conditioned with super-low dose LPS. Collectively, our findings reveal a mechanism potentially responsible for the dynamic programming of innate immunity in vivo as it relates to sepsis risks. PMID:26029736

  12. Differential effects of glucocorticoids in the establishment and maintenance of endotoxin tolerance.

    PubMed

    Rearte, B; Landoni, V; Laborde, E; Fernández, G; Isturiz, M

    2010-02-01

    Gram-negative infections can result in endotoxic shock, which is the most common cause of death in intensive care units. Most of the undesirable effects in sepsis and septic shock have been ascribed to lipopolysaccharide (LPS), a normal constituent of the bacterial wall. The response to LPS involves rapid secretion of proinflammatory cytokines [tumour necrosis factor-alpha, interleukin (IL)-1, IL-6, IL-8, interferon-gamma] and the concomitant induction of anti-inflammatory mediators such as IL-10 and transforming growth factor-beta and glucocorticoids (GC), which render the host temporarily refractory to subsequent lethal doses of LPS challenge in a process known as LPS or endotoxin tolerance. Although protective from the development of sepsis or systemic inflammation, endotoxin tolerance has also been pointed out as the principal cause of the non-specific immunosuppression described in these patients. In this report we demonstrate, using a mouse model, that while the maintenance of tolerance is dependent upon GC, the establishment of tolerance by LPS could be inhibited by dexamethasone (Dex), a synthetic GC. Conversely, we demonstrated that mifepristone (RU486), a known GC receptor antagonist, was capable of inducing a transient and reversible disruption of endotoxin tolerance, also permitting partial restoration of the humoral immune response in LPS tolerant/immunosuppressed mice. These results are encouraging for the management of immunosuppression in sepsis and/or non-infectious shock, and deserve further investigation in the future. PMID:19912256

  13. Endotoxins enhance hepatocarcinogenesis induced by oral intake of thioacetamide in rats

    PubMed Central

    Yang, Jin-Ming; Han, De-Wu; Xie, Chun-Ming; Liang, Quan-Cheng; Zhao, Yuan-Chang; Ma, Xue-Hui

    1998-01-01

    AIM: To clarify whether endotoxin is of pathogenic importance for hepatocarcinogenesis,or the increased cancer risk results solely from thecirrhotic process. METHODS: The rat model of hepatoma was treated by the intake of 0.03% thioacetamide in drinking water for six months. During induction of hepatoma, rats were additionally treated with splenectomy and/or lipopolysaccharide administration. The liver nuclear DNA index and proliferation index were quantitatively analyzed by flow cytometry. Hepatic histology was examined with light and electron microscopes. Plasmic endotoxin concentration and ?-glutamyl transpeptidase activity were measured, and hepatoma incidence was recorded. RESULTS: Thioacetamide induced cirrhosis and hepatoma in Wistar rats with histology or regenerative nodule, fibrosis and neoplastic foci were quite similar to the pathogenic process of human cirrhosis leading to hepatoma. In comparison with TAA controls (DNA index: 1.15 ± 0.21), exo-endotoxin increased the DNA index by 7.8% (1.24 ± 0.25, P < 0.02) and hepatoma rate by 16.7. Splenectomy-induced enteric endotoxemia increased the DNA index by 25% (1.44 ± 0.15, P < 0.01) and hepatoma rate by 33%. A summation of the effects of these two factors increased the DNA index by 36% (P£¼0.01)and hepatoma incidence by 50%, moreover, the level of endotoxemia showed a close relation with DNA index (r = 0.96, P < 0.01), as well as with the occurrence rate of hepatoma (r = 0.00, P < 0.01). Histological findings further verified such alterations. CONCLUSION: Lipopolysaccharide administration and/or splenectomy-induced enterogenic endotoxemia may enhance rat hepatocarcinogenesis induced by oral intake of thioacetamide. PMID:11819255

  14. Effect of naloxone on regional cerebral blood flow during endotoxin shock in conscious rats

    SciTech Connect

    Law, W.R.; Ferguson, J.L. )

    1987-09-01

    Maintenance of cerebral blood flow (CBF) is vital during cardiovascular shock. Since opioids have been implicated in the pathophysiology of endotoxin shock and have been shown to alter cerebral perfusion patterns, the authors determined whether opioids were responsible for any of the changes in regional CBF observed during endotoxin shock and whether the use of naloxone might impair or aid in the maintenance of CBF. When blood flow (BF) is studied with radioactively-labeled microspheres in rats, the left ventricle of the heart is often cannulated via the right carotid artery. Questions have arisen concerning the potential adverse effects of this method on CBF in the hemisphere ipsilateral to the ligated artery. They measured right and left regional CBF by use of this route of cannulation. Twenty-four hours after cannulations were performed, flow measurements were made using radiolabeled microspheres in conscious unrestrained male Sprague-Dawley rats (300-400 g) before and 10, 30, and 60 min after challenging with 10 mg/kg Escherichia coli endotoxin (etx) or saline. Naloxone (2 mg/kg) or saline was given as a treatment 25 min post-etx. They found no significant differences between right and left cortical, midbrain, or cerebellar BF at any time in any treatment group. Therefore naloxone treatment of endotoxin shock may be beneficial in preventing decreases in regional CBF.

  15. Effect of Zingiber officinale and propolis on microorganisms and endotoxins in root canals

    PubMed Central

    MAEKAWA, Lilian Eiko; VALERA, Marcia Carneiro; de OLIVEIRA, Luciane Dias; CARVALHO, Cláudio Antonio Talge; CAMARGO, Carlos Henrique Ribeiro; JORGE, Antonio Olavo Cardoso

    2013-01-01

    The purpose of this study was to evaluate the effectiveness of glycolic propolis (PRO) and ginger (GIN) extracts, calcium hydroxide (CH), chlorhexidine (CLX) gel and their combinations as ICMs (ICMs) against Candida albicans, Enterococcus faecalis, Escherichia coli and endotoxins in root canals. Material and Methods: After 28 days of contamination with microorganisms, the canals were instrumented and then divided according to the ICM: CH+saline; CLX, CH+CLX, PRO, PRO+CH; GIN; GIN+CH; saline. The antimicrobial activity and quantification of endotoxins by the chromogenic test of Limulus amebocyte lysate were evaluated after contamination and instrumentation at 14 days of ICM application and 7 days after ICM removal. Results and Conclusion: After analysis of results and application of the Kruskal-Wallis and Dunn statistical tests at 5% significance level, it was concluded that all ICMs were able to eliminate the microorganisms in the root canals and reduce their amount of endotoxins; however, CH was more effective in neutralizing endotoxins and less effective against C. albicans and E. faecalis, requiring the use of medication combinations to obtain higher success. PMID:23559108

  16. Detection of endotoxin in the plasma of patients with gram-negative bacterial sepsis by the Limulus amoebocyte lysate assay.

    PubMed

    Pearson, F C; Dubczak, J; Weary, M; Bruszer, G; Donohue, G

    1985-06-01

    A total of 120 Limulus amoebocyte lysate (LAL) determinations were made on plasma obtained from normal, healthy human blood donors. Results demonstrated a mean endotoxin level in blood of 0.02 to 1.57 pg/ml. The amount of Escherichia coli endotoxin added to human plasma samples can be quantitated by both nephelometry and turbidimetry. Endotoxin-spiked samples were shown to be significantly different from unspiked samples. When plasma samples were collected from 45 patients hospitalized at three centers, a strong association was demonstrated between a positive Limulus amoebocyte lysate assay and a septic condition. Sensitivity, specificity, and false-positive and false-negative rates for the Limulus amoebocyte lysate assay as a diagnostic test for gram-negative bacteremia were estimated. PMID:4008617

  17. Endotoxins in cotton: washing effects and size distribution

    SciTech Connect

    Olenchock, S.A.; Mull, J.C.; Jones, W.G.

    1983-01-01

    Endotoxin contamination was measured in washed and unwashed cottons from three distinct growing areas, California, Mississippi, and Texas. The data show differences in endotoxin contamination based upon the geographic source of the cotton. It is also shown that washing bulk cotton before the carding process results in lower endotoxin in the cotton dust. Washing conditions can affect the endotoxin levels, and all size fractions of the airborne dust contain quantifiable endotoxin contamination. Endotoxin analyses provide a simple and reliable method for monitoring the cleanliness of cotton or airborne cotton dusts.

  18. A true theranostic approach to medicine: towards tandem sensor detection and removal of endotoxin in blood.

    PubMed

    Thompson, Michael; Blaszykowski, Christophe; Sheikh, Sonia; Romaschin, Alexander

    2015-05-15

    Sepsis is one of the leading causes of death around the world. The condition occurs when a local infection overcomes the host natural defense mechanism and suddenly spreads into the circulatory system, triggering a vigorous, self-injurious inflammatory host response. The pathogenesis of sepsis is relatively well known, one of the most potent immuno-activator being bacterial lipopolysaccharide (LPS) - also known as 'endotoxin'. Tests exist to detect endotoxin in bodily fluids, but are expensive, not necessarily user-friendly and require reporter molecules. In addition, the situation for safe and effective anti-endotoxin therapy is problematical. At the present time, endotoxin removal through cartridge hemoperfusion is one of the better alternatives to combat sepsis. The capability to both measure endotoxemia levels and offer an adapted response treatment in a timely manner is crucial for better management and improved prognosis, but is currently unavailable. In this context, we describe herein preliminary research towards the development of an alternative LPS biosensor and an innovative LPS neutralization cartridge to be eventually combined in an all-integrated configuration for the theranostic, personalized treatment of blood endotoxemia/sepsis. LPS detection is performed in a real-time and label-free manner in full human blood plasma, using ultra-high frequency acoustic wave sensing in combination with ultrathin, oligoethylene glycol-based mixed surface chemistry imposed on piezoelectric quartz discs. Biosensing platforms are functionalized with polymyxin B (PMB), a cyclic peptide antibiotic with high affinity for LPS. Analogous surface modification is used on glass beads for the therapeutic cartridge component of the combined strategy. Incubation of LPS-spiked whole blood with PMB-bead chemistry resulted in a significant decrease in the production of pro-inflammatory TNF-? cytokine. LPS neutralization is discussed in relation to the perturbation of its supramolecular chemistry in solution. PMID:25067837

  19. Lipopolysaccharide-induced apoptosis in swine lymphocytes in vivo.

    PubMed Central

    Norimatsu, M; Ono, T; Aoki, A; Ohishi, K; Takahashi, T; Watanabe, G; Taya, K; Sasamoto, S; Tamura, Y

    1995-01-01

    The in vivo effects of bacterial lipopolysaccharide (LPS) on the immune systems of piglets were investigated. Intravenous injection of 0.5 mg of LPS per kilogram of body weight induced apoptosis, which was characterized by nuclear chromatin condensation and fragmentation and a ladder formation of nucleosomal DNA in lymphocytes both in the cortex of the thymus and in the germinal centers and paracortical areas of mesenteric lymph nodes at 24 h postinjection. The levels of endotoxin, tumor necrosis factor alpha, and cortisol in serum increased, generally according to the dose of LPS. These findings suggest that LPS can induce in vivo apoptosis of lymphocytes in piglets and support the notion that cytokine and endocrine responses may play an important role in LPS-induced apoptosis in the immune system. PMID:7868236

  20. MECHANISMS OF ENDOTOXIN TOLERANCE. 3. THE REFRACTORY STATE DURING CONTINUOUS INTRAVENOUS INFUSIONS OF ENDOTOXIN.

    PubMed

    GREISMAN, S E; WOODWARD, W E

    1965-06-01

    Bacterial endotoxins were administered by continuous intravenous infusions at constant rates to normal man and rabbits. An initial progressive febrile reaction was followed by progressive defervescence to baseline. The resulting pyrogenic refractory state was characterized as follows: (a) reticuloendothelial blockade with thorotrast neither prevented nor reversed its course; (b) passive transfer was unsuccessful with refractory phase plasma; (c) infusions of normal plasma or fresh whole blood failed to restore responsiveness; (d) a minimum of 4 hours of continuous endotoxin infusion was required for full development of unresponsiveness; (e) circulating antibody titers to endotoxin remained unaltered; (f) peripheral leukocytosis appeared; (g) infusion of febrile phase plasma reevoked an immediate, monophasic fever; (h) endotoxinemia could be demonstrated by pyrogen bioassay; (i) 10-fold increases in endotoxin infusion rates reevoked fever; (j) impaired responsiveness extended to heterologous endotoxins; (k) dermal inflammatory responses to endotoxin were suppressed in man while tuberculin reactivity remained unimpaired; dermal inflammatory responses to endotoxin were enhanced in rabbits; and (l) pyrogenic reactivity to endotoxin reappeared within 24 hours in man; refractoriness persisted in rabbits. It is concluded that the pyrogenic refractory state reflects an inability of the host to continue to mobilize endogenous pyrogen during sustained endotoxinemia. Such observations, together with previous studies, are consistent with two distinct immunologic mechanisms of resistance to endotoxin pyrogenicity: (a) desensitization at the cellular level; and (b) elaboration of circulating antibodies which assist reticuloendothelial clearance and destruction of endotoxin. Whereas both such mechanisms may contribute to pyrogenic tolerance, the characteristics of the pyrogenic refractory state suggest the participation only of the former. PMID:14319407

  1. Lipopolysaccharides of Salmonella T Mutants

    PubMed Central

    Wheat, R. W.; Berst, M.; Ruschmann, E.; Lüderitz, O.; Westphal, O.

    1967-01-01

    The composition of lipopolysaccharides derived from various Salmonella T forms was studied. All T1-form lipopolysaccharides examined contained 14 to 22% each of both d-galactose and pentose in addition to 4 to 9% each of ketodeoxyoctonic acid, heptose, d-glucosamine, and d-glucose. The pentose was identified as d-ribose. The T2-form lipopolysaccharide examined did not contain a significant amount of pentose, nor more than the usual amounts of d-galactose. Periodate oxidation of T1 (lipo) polysaccharides followed by NaBH4 reduction revealed that ribose was almost quantitatively protected, galactose was destroyed, and threitol and mannose were newly formed. The latter two products probably originated from 4-linked galactose and heptose, respectively. Ribose and galactose were found in specific precipitates of T1 lipopolysaccharide with anti-T1 antiserum but were not found in specific precipitates of alkali-treated T1 lipopolysaccharide and of Freeman degraded polysaccharide with anti-T1 serum Ribose and galactose are present in these degraded preparations in the form of nondialyzable polymers. The T1-form mutant lipopolysaccharides lacked the O-specific sugars constituting the side-chains in the wild-type antigens. They did not produce the soluble O-specific haptenic polysaccharide known to be accumulated in RI strains. With these properties, T1 lipopolysaccharides resemble RII lipopolysaccharides. Like RII degraded polysaccharides, T1-degraded polysaccharides also contained glucosamine. Furthermore, strong cross-reactions were found to exist between T1 and RII lipopolysaccharides in both hemagglutination inhibition assays and in precipitation tests. It is proposed that T1 lipopolysaccharides represent RII lipopolysaccharides to which polymers consisting of ribose and galactose are attached. PMID:6057795

  2. Altered Toll-like Receptor 2-mediated Endotoxin Tolerance Is Related to Diminished Interferon ? Production

    PubMed Central

    Zaric, Svetislav S.; Coulter, Wilson A.; Shelburne, Charles E.; Fulton, Catherine R.; Zaric, Marija S.; Scott, Aaron; Lappin, Mark J.; Fitzgerald, Denise C.; Irwin, Christopher R.; Taggart, Clifford C.

    2011-01-01

    Induction of endotoxin tolerance leads to a reduced inflammatory response after repeated challenge by LPS and is important for resolution of inflammation and prevention of tissue damage. Enterobacterial LPS is recognized by the TLR4 signaling complex, whereas LPS of some non-enterobacterial organisms is capable of signaling independently of TLR4 utilizing TLR2-mediated signal transduction instead. In this study we report that Porphyromonas gingivalis LPS, a TLR2 agonist, fails to induce a fully endotoxin tolerant state in a human monocytic cell line (THP-1) and mouse bone marrow-derived macrophages. In contrast to significantly decreased production of human IL-8 and TNF-? and, in mice, keratinocyte-derived cytokine (KC), macrophage inflammatory protein-2 (MIP-2), and TNF-? after repeated challenge with Escherichia coli LPS, cells repeatedly exposed to P. gingivalis LPS responded by producing less TNF-? but sustained elevated secretion of IL-8, KC, and MIP-2. Furthermore, in endotoxin-tolerant cells, production of IL-8 is controlled at the signaling level and correlates well with NF-?B activation, whereas TNF-? expression is blocked at the gene transcription level. Interferon ? plays an important role in attenuation of chemokine expression in endotoxin-tolerized cells as shown in interferon regulatory factor-3 knock-out mice. In addition, human gingival fibroblasts, commonly known not to display LPS tolerance, were found to be tolerant to repeated challenge by LPS if pretreated with interferon ?. The data suggest that the inability of the LPS-TLR2 complex to induce full endotoxin tolerance in monocytes/macrophages is related to diminished production of interferon ? and may partly explain the involvement of these LPS isoforms in the pathogenesis of chronic inflammatory diseases. PMID:21705332

  3. Effect of endotoxin on portal hemodynamic in rats

    PubMed Central

    Bi, Xiang-Jun; Chen, Min-Hu; Wang, Jing-Hui; Chen, Jie

    2002-01-01

    AIM: To study the effects of endotoxin on portal hemodynamic of normal and noncirrhotic portal hypertensive rats. METHODS: Normal rats were intraperitonealy injected with 0.1, 0.25, 0.5, 1.0, 2.0, 4.0 mg·kg-1 of lipopolysaccharide (LPS) respectively, portal vein ligation (PVL) and intrahepatic portal occlusion (IPO) rats as well as sham-operated rats were treated with an intraperitoneal injection of 1.0 mg·kg-1 of LPS, the portal vein pressure (PVP), portal venous flow (PVF), inferior vena cava pressure (IVCP) and portal vein resistance (PVR) were detected 4 hours after injection. RESULTS: PVF of the 5 groups of rats accepting intraperitoneal injection of LPS were increased from 14.0 to 18.0, 22.2, 26.2, 34.8, 39.6, 38.8 mL·min-1 4 hours after injection of LPS (P < 0.01). PVP of the 4 groups of rats accepting more than 0.1 mg/kg·b.w of LPS was increased from 1.04 to1.25, 1.50, 1.80, 1.95, 2.05 kPa (P < 0.01). The increments of PVF and PVP were in a dose-dependent manner of LPS. PVR of the 5 groups of rats was decreased from 51 to 42, 44, 48, 45, 44, 47 kPa·min·L-1 (P < 0.05) and no dose-dependent manner was observed. PVF of PVL, IPO and sham-operated rats increased from 22.6 to 32.8, 22.0 to 28.0, 14.0 to 34.8 mL·min-1 (P < 0.01), and PVP increased from 1.86 to 2.24, 1.74 to 1.95, 1.04 to 1.80 kPa (P < 0.01), PVR decreased from 71 to 61, 67 to 61, 52 to 44 kPa·min·L-1 after intraperitoneal injection of 1 mg·kg-1 of LPS. The increments of PVF and PVP of PVL and IPO rats were significantly less than the sham-operated rats (P < 0.01), There was no significant difference between the amounts of PVR decreased in the two groups of PHT model rats and sham-operated rats (P > 0.05) after intraperitoneal injection 1 mg·kg-1 of LPS. CONCLUSION: Endotoxin could prompt portal hypertension of the normal and noncirrhotic portal hypertensive rats by increasing portal blood flow mainly. PMID:12046085

  4. Ambient endotoxin concentrations in PM10 from Southern California.

    PubMed Central

    Mueller-Anneling, Linda; Avol, Ed; Peters, John M; Thorne, Peter S

    2004-01-01

    Concentrations of endotoxin in urban air pollution have not previously been extensively characterized. We measured 24-hr levels of PM10 (particulate matter < 10 microm in aerodynamic diameter) and the associated endotoxin component once every 6 weeks for 1 year in 13 communities in Southern California. All the samples collected had detectable PM10 and endotoxin levels. The geometric mean PM10 was 34.6 microg/m3 [geometric SD (GSD), 2.1; range, 3.0-135]. By volume, the endotoxin geometric mean was 0.44 endotoxin units (EU)/m3 (GSD, 3.1; range, 0.03-5.44). Per unit material collected, the geometric mean of endotoxin collected was 13.6 EU/mg (GSD, 3.2; range, 0.7-96.8). No correlation was found between endotoxin concentrations and other ambient pollutants concurrently measured [ozone, nitrogen dioxide, total acids, or PM2.5 (particulate matter < 2.5 micro m in aerodynamic diameter]. PM10 and endotoxin concentrations were significantly correlated, most strongly in summer. Samples collected in more rural and agricultural areas had lower PM10 and mid-range endotoxin levels. The high desert and mountain communities had lower PM10 levels but endotoxin levels comparable with or higher than the rural agricultural sites. By volume, endotoxin levels were highest at sites downwind of Los Angeles, California, which were also the locations of highest PM10. Endotoxin concentrations measured in this study were all < 5.5 EU/m3, which is lower than recognized thresholds for acute adverse health effects for occupational exposures but in the same range as indoor household concentrations. This study provides the first extensive characterization of endotoxin concentration across a large metropolitan area in relation to PM10 and other pollutant monitoring, and supports the need for studies of the role of endotoxin in childhood asthma in urban settings. PMID:15064165

  5. Interactions of Bacterial Lipopolysaccharides with Gold Nanorod Surfaces Investigated by Refractometric Sensing.

    PubMed

    Abadeer, Nardine S; Fülöp, Gerg?; Chen, Si; Käll, Mikael; Murphy, Catherine J

    2015-11-11

    The interface between nanoparticles and bacterial surfaces is of great interest for applications in nanomedicine and food safety. Here, we demonstrate that interactions between gold nanorods and bacterial surface molecules are governed by the nanoparticle surface coating. Polymer-coated gold nanorod substrates are exposed to lipopolysaccharides extracted from Pseudomonas aeruginosa, Salmonella enterica and Escherichia coli, and attachment is monitored using localized surface plasmon resonance refractometric sensing. The number of lipopolysaccharide molecules attached per nanorod is calculated from the shift in the plasmon maximum, which results from the change in refractive index after analyte binding. Colloidal gold nanorods in water are also incubated with lipopolysaccharides to demonstrate the effect of lipopolysaccharide concentration on plasmon shift, ?-potential, and association constant. Both gold nanorod surface charge and surface chemistry affect gold nanorod-lipopolysaccharide interactions. In general, anionic lipopolysaccharides was found to attach more effectively to cationic gold nanorods than to neutral or anionic gold nanorods. Some variation in lipopolysaccharide attachment is also observed between the three strains studied, demonstrating the potential complexity of bacteria-nanoparticle interactions. PMID:26488238

  6. COX-2 mediated induction of endothelium-independent contraction to bradykinin in endotoxin-treated porcine coronary artery.

    PubMed

    More, Amar S; Kim, Hye Min; Zhao, Ru; Khang, Gilson; Hildebrandt, Tobias; Bernlöhr, Christian; Doods, Henri; Lee, Dongwon; Lee, Seung Hee; Vanhoutte, Paul M; Wu, Dongmei

    2014-09-01

    This study examined the vascular effects of bradykinin in health and vascular inflammation comparing responses of isolated pig coronary arteries in the absence and presence of endotoxins. Bradykinin induced contractions in lipopolysaccharide-treated, but not untreated, arterial rings without endothelium. The B2-receptor antagonist HOE140, but not the B1-receptor inhibitor SSR240612, blocked these endothelium-independent contractions in response to bradykinin. The bradykinin-induced contractions were blocked by indomethacin, celecoxib, and terbogrel but not valeryl salicylate, AH6809, AL 8810, or RO1138452. They were attenuated by N-(p-amylcinnamoyl) anthranilic acid, and by diethyldithiocarbamate plus tiron but not by L-NAME. Quantitative reverse-transcription polymerase chain reaction revealed significant upregulations of messenger RNA expressions of B1 receptors, COX-2, and thromboxane A synthase 1 (TBXAS1) following lipopolysaccharide incubation but not of B2 receptors or COX-1. The present data demonstrate that bradykinin induces contractions mediated by the COX-2 pathway in endotoxin-treated pig coronary arteries. These results support differential roles of bradykinin in health and disease. PMID:25192543

  7. Removal of endotoxin from dairy wastewater

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The efficacy of various treatments on removing endotoxin (ET) from wastewater was tested by using the treated water to induce a systemic reaction via intratracheal inoculation (20 ml/goat, 6 goats/group). Treatments (T1-T7) of wastewater were as follows: 1) autoclaved 15 min, centrifuged and contain...

  8. Anti-CD14 mAb treatment provides therapeutic benefit after in vivo exposure to endotoxin

    PubMed Central

    Schimke, Jan; Mathison, John; Morgiewicz, Janice; Ulevitch, Richard J.

    1998-01-01

    The presence of endotoxin from Gram-negative bacteria signals the innate immune system to up-regulate bacterial clearance and/or killing mechanisms. Paradoxically, such responses also contribute to septic shock, a clinical problem occurring with high frequency in Gram-negative septicemia. CD14 is a receptor for endotoxin (lipopolysaccharide, LPS) and is thought to have an essential role in innate immune responses to infection and thereby in the development of septic shock. Using a novel rabbit model of endotoxic shock produced by multiple exposures to endotoxin, we show that anti-rabbit CD14 mAb, which blocks LPS-CD14 binding, protects against organ injury and death even when the antibody is administered after initial exposures to LPS. In contrast, anti-rabbit tumor necrosis factor mAb treatment fails to protect when administered after LPS injections. These results support the concept that anti-CD14 treatment provides a new therapeutic window for the prevention of pathophysiologic changes that result from cumulative exposures to LPS during septic shock in man. PMID:9811894

  9. Identification of single nucleotide polymorphisms in hematopoietic cell transplant patients affecting early recognition of, and response to, endotoxin

    PubMed Central

    Guinan, Eva C; Palmer, Christine D; Mancuso, Christy J; Brennan, Lisa; Stoler-Barak, Liat; Kalish, Leslie A; Suter, Eugenie E; Gallington, Leighanne C; Huhtelin, David P; Mansilla, Maria; Schumann, Ralf R; Murray, Jeffrey C; Weiss, Jerrold; Levy, Ofer

    2014-01-01

    Hematopoietic cell transplant (HCT) is a life-saving therapy for many malignant and non-malignant bone marrow diseases. Associated morbidities are often due to transplant-related toxicities and infections, exacerbated by regimen-induced immune suppression and systemic incursion of bacterial products. Patients undergoing myeloablative conditioning for HCT become endotoxemic and display blood/plasma changes consistent with lipopolysaccharide (LPS)-induced systemic innate immune activation. Herein, we addressed whether patients scheduled for HCT display differences in recognition/response to LPS ex vivo traceable to specific single nucleotide polymorphisms (SNPs). Two SNPs of LPS binding protein (LBP) were associated with changes in plasma LBP levels, with one LBP SNP also associating with differences in efficiency of extraction and transfer of endotoxin to myeloid differentiation factor-2 (MD-2), a step needed for activation of TLR4. None of the examined SNPs of CD14, bactericidal/permeability-increasing protein (BPI), TLR4 or MD-2 were associated with corresponding protein plasma levels or endotoxin delivery to MD-2, but CD14 and BPI SNPs significantly associated with differences in LPS-induced TNF-? release ex vivo and infection frequency, respectively. These findings suggest that specific LBP, CD14 and BPI SNPs might be contributory assessments in studies where clinical outcome may be affected by host response to endotoxin and bacterial infection. PMID:24107515

  10. Analusis by 252Cf plasma desorption mass spectrometry of Bordetella pertussis endotoxin after nitrous deamination

    NASA Astrophysics Data System (ADS)

    Deprun, C.; Karibian, D.; Caroff, M.

    1993-07-01

    Endotoxic lipopolysaccharides (LPSs) are the major components of Gram-negative bacterial outer membrane. Like many amphipathic molecules, they pose problems of heterogeneity, purity, solubility, and aggregation. Nevertheless, PDMS has recently have been applied to unmodified endotoxins composed of LPS having uip to five sugar units in their saccharide chain. The B. Pertussis LPSs, most of which have a dodecasaccharide domain, ahve been analysed by classical methods and the masses of the separate lipid and saccharide domains determined after rupture of the bond linking them. However, the acid treatment employed for these and most chemical analyses can also modify structures in the vicinity of the bond. In order to investigate this biologically-important region, the endotoxin was treated to nitrous deamination, which shortens the saccharide chain to five sugars, but preserves the acid-labile region of the LPS. The PDM spectrum of this derivative, which required new conditions for its desorption, confirmed the structure analysis and demonstrated the presence of at least four molecular species.

  11. Lipopolysaccharide-Binding Alkylpolyamine DS-96 Inhibits Chlamydia trachomatis Infection by Blocking Attachment and Entry

    E-print Network

    Osaka, Ichie; Hefty, Scott

    2014-03-24

    to Escherichia coli lipid A, was previously demonstrated to bind and neutralize lipopolysaccharide (LPS) from a wide variety of Gram-negative bacteria (D. Sil et al., Antimicrob. Agents Chemother. 51:2811–2819, 2007, doi:10.1128/AAC.00200-07). Aside from the lack...

  12. Airborne endotoxin in fine particulate matter in Beijing

    NASA Astrophysics Data System (ADS)

    Guan, Tianjia; Yao, Maosheng; Wang, Junxia; Fang, Yanhua; Hu, Songhe; Wang, Yan; Dutta, Anindita; Yang, Junnan; Wu, Yusheng; Hu, Min; Zhu, Tong

    2014-11-01

    Endotoxin is an important biological component of particulate matter (PM) which, upon inhalation, can induce adverse health effects, and also possibly complicate the diseases in combination with other pollutants. From 1 March 2012 to 27 February 2013 we collected air samples using quartz filters daily for the quantification of airborne endotoxin and also fine PM (PM2.5) in Beijing, China. The geometric means for endotoxin concentration and the fraction of endotoxin in PM were 0.65 EU/m3 (range: 0.10-75.02) and 10.25 EU/mg PM2.5 (range: 0.38-1627.29), respectively. The endotoxin concentrations were shown to vary greatly with seasons, typically with high values in the spring and winter seasons. Temperature and relative humidity, as well as concentrations of sulfur dioxide and nitrogen oxides were found to be significantly correlated with airborne endotoxin concentrations (p < 0.05). Additionally, positive correlations were also detected between endotoxin concentrations and natural sources of Na+, K+, Mg2+, and F-, while negative correlations were observed between endotoxin concentrations and anthropogenic sources of P, Co, Zn, As, and Tl. Oxidative potential analysis revealed that endotoxin concentrations were positively correlated with reactive oxygen species (ROS), but not dithiothreitol (DTT) of PM. This study provided the first continuous time series of airborne endotoxin concentrations in Beijing, and identifies its potential associations with atmospheric factors. The information developed here can assist in the assessment of health effects of air pollution in Beijing.

  13. E. Coli

    MedlinePLUS

    ... CDC Cancel Submit Search The CDC E.coli (Escherichia coli) Note: Javascript is disabled or is not supported ... Recommend on Facebook Tweet Share Compartir E. coli (Escherichia coli) General Information E. coli O157:H7 Infections Linked ...

  14. Interception of the endotoxin-induced arterial hyporeactivity to vasoconstrictors

    PubMed Central

    Zhang, Shuang; Cui, Ningren; Li, Shanshan; Guo, Lei; Wu, Yang; Zhu, Daling; Jiang, Chun

    2014-01-01

    Septic shock is a severe pathophysiologic condition characterized by vasodilation, hypotension, hypoperfusion, tissue hypoxia, multiple organ failure and death. It is unclear what causes the septic vasodilation that may result from general dysfunction of vascular smooth muscles (VSMs) or selective disruption of vasomotor balances in VSMs. The latter could be due to enhanced vasorelaxation and/or depressed vasoconstriction. Understanding these may lead to pharmacological interventions to septic vasodilation. Therefore, we performed studies in isolated and perfused mesenteric arterial rings. A 20-h exposure of the rings to lipopolysaccharide (LPS, 1?g/ml) led to hyporeactivity to phenylephrine (PE). However, the responses of the LPS-treated rings to high concentrations of KCl (60mM) and ATP remained comparable to control rings, suggesting that contractility of VSMs is retained. The hyporeactivity was marginally affected by atropine, indomethacin and L-NAME, suggesting that endothelium-dependent vasorelaxation does not play a major role. In addition to PE, the LPS-treated rings were hyporeactive to dopamine, histamine and angiotensin II. They showed intermediate hyporeactivity to the thromboxane-A2 receptor agonist U46619. Little hyporeactivity to endothelin-1 (ET-1), serotonin (5-HT) and vasopressin was found. ET-1-induced vasoconstriction occurred without endothelium, whereas the effect of serotonin was endothelium dependent. Although rings were hyporeactive to some of the vasopressors, their vasoconstriction effects were significantly potentiated by PE co-application. Taken together, these data suggest that the endotoxin-induced vasodilation may not result from general dysfunction of VSMs, neither from the endothelium-dependent vasorelaxation. The promising vascular response to various vasoconstrictors found in this study warrants further investigations of therapeutic potentials of these agents. PMID:24792896

  15. Endotoxin-Induced Changes in Phospholipid Dynamics of the Stomach

    PubMed Central

    Dial, Elizabeth J.; Tran, Duy M.; Hyman, Ari; Lichtenberger, Lenard M.

    2012-01-01

    Background The gastric mucosa is protected in part by a hydrophobic layer of phosphatidylcholine (PC) that overlies the mucus gel on the stomach. Endotoxin treatment (i.e., lipopolysaccharide or LPS) results in an apparent disruption of this layer as evidenced by a reduction in surface hydrophobicity and an increase in transmural permeability. The current studies compared PC and lyso-PC levels in mucus and gastric mucosa before and after LPS treatment, and examined potential mechanisms for surface phospholipid changes. Methods Rats were administered LPS (5 mg//kg, ip) and samples were collected after 5 h for analysis of PC and its primary degradant, lyso-PC, in the loosely and firmly adherent mucus layers, and the mucosa. The dependence of LPS-induced effects on gastric alkalinization, PC synthetic activity, and intestinal reflux material was assessed. Results The gastric contents after LPS, which also contained duodenal reflux material, had greatly increased amounts of PC and lyso-PC. The firmly adherent mucus layer was unchanged. The gastric mucosa after LPS revealed significant reductions of PC levels and no change in lyso-PC content. These phospholipid changes were not caused by alkalinization of the stomach or altered PC synthesis. Prevention of duodenogastric reflux by pylorus ligation blocked the LPS-induced increase in luminal lyso-PC and the reduction in mucosal PC. Conclusions LPS appears to induce a release of PC from gastric mucosa into the lumen, along with degradation of PC to lyso-PC, without an affect on PC synthesis. Component(s) of intestinal reflux material appear to be required for these effects. The lowered PC levels in gastric mucosa after LPS may contribute to reduced barrier properties of this tissue. PMID:23158407

  16. Diet-induced obesity attenuates endotoxin-induced cognitive deficits.

    PubMed

    Setti, Sharay E; Littlefield, Alyssa M; Johnson, Samantha W; Kohman, Rachel A

    2015-03-15

    Activation of the immune system can impair cognitive function, particularly on hippocampus dependent tasks. Several factors such as normal aging and prenatal experiences can modify the severity of these cognitive deficits. One additional factor that may modulate the behavioral response to immune activation is obesity. Prior work has shown that obesity alters the activity of the immune system. Whether diet-induced obesity (DIO) influences the cognitive deficits associated with inflammation is currently unknown. The present study explored whether DIO alters the behavioral response to the bacterial endotoxin, lipopolysaccharide (LPS). Female C57BL/6J mice were fed a high-fat (60% fat) or control diet (10% fat) for a total of five months. After consuming their respective diets for four months, mice received an LPS or saline injection and were assessed for alterations in spatial learning. One month later, mice received a second injection of LPS or saline and tissue samples were collected to assess the inflammatory response within the periphery and central nervous system. Results showed that LPS administration impaired spatial learning in the control diet mice, but had no effect in DIO mice. This lack of a cognitive deficit in the DIO female mice is likely due to a blunted inflammatory response within the brain. While cytokine production within the periphery (i.e., plasma, adipose, and spleen) was similar between the DIO and control mice, the DIO mice failed to show an increase in IL-6 and CD74 in the brain following LPS administration. Collectively, these data indicate that DIO can reduce aspects of the neuroinflammatory response as well as blunt the behavioral reaction to an immune challenge. PMID:25542778

  17. 40 CFR 180.1107 - Delta endotoxin of Bacillus thuringiensis variety kurstaki encapsulated into killed Pseudomonas...

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...2014-07-01 2014-07-01 false Delta endotoxin of Bacillus thuringiensis variety...Exemptions From Tolerances § 180.1107 Delta endotoxin of Bacillus thuringiensis variety...the requirement of a tolerance. The delta endotoxin of Bacillus thuringiensis...

  18. 40 CFR 180.1107 - Delta endotoxin of Bacillus thuringiensis variety kurstaki encapsulated into killed Pseudomonas...

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...2013-07-01 2013-07-01 false Delta endotoxin of Bacillus thuringiensis variety...Exemptions From Tolerances § 180.1107 Delta endotoxin of Bacillus thuringiensis variety...the requirement of a tolerance. The delta endotoxin of Bacillus thuringiensis...

  19. 40 CFR 180.1107 - Delta endotoxin of Bacillus thuringiensis variety kurstaki encapsulated into killed Pseudomonas...

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ...2012-07-01 2012-07-01 false Delta endotoxin of Bacillus thuringiensis variety...Exemptions From Tolerances § 180.1107 Delta endotoxin of Bacillus thuringiensis variety...the requirement of a tolerance. The delta endotoxin of Bacillus thuringiensis...

  20. 40 CFR 180.1107 - Delta endotoxin of Bacillus thuringiensis variety kurstaki encapsulated into killed Pseudomonas...

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...2011-07-01 2011-07-01 false Delta endotoxin of Bacillus thuringiensis variety...Exemptions From Tolerances § 180.1107 Delta endotoxin of Bacillus thuringiensis variety...the requirement of a tolerance. The delta endotoxin of Bacillus thuringiensis...

  1. 40 CFR 180.1107 - Delta endotoxin of Bacillus thuringiensis variety kurstaki encapsulated into killed Pseudomonas...

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...2010-07-01 2010-07-01 false Delta endotoxin of Bacillus thuringiensis variety...Exemptions From Tolerances § 180.1107 Delta endotoxin of Bacillus thuringiensis variety...the requirement of a tolerance. The delta endotoxin of Bacillus thuringiensis...

  2. Role of endotoxemia in cardiovascular dysfunction and mortality. Escherichia coli and Staphylococcus aureus challenges in a canine model of human septic shock.

    PubMed Central

    Natanson, C; Danner, R L; Elin, R J; Hosseini, J M; Peart, K W; Banks, S M; MacVittie, T J; Walker, R I; Parrillo, J E

    1989-01-01

    Using different types of bacteria and a canine model simulating human septic shock, we investigated the role of endotoxin in cardiovascular dysfunction and mortality. Either Escherichia coli (a microorganism with endotoxin) or Staphylococcus aureus (a microorganism without endotoxin) were placed in an intraperitoneal clot in doses of viable or formalin-killed bacteria. Cardiovascular function of conscious animals was studied using simultaneous radionuclide heart scans and thermodilution cardiac outputs. Serial plasma endotoxin levels were measured. S. aureus produced a pattern of reversible cardiovascular dysfunction over 7-10 d that was concordant (P less than 0.01) with that of E. coli. Although this cardiovascular pattern was not altered by formalin killing (S. aureus and E. coli), formalin-killed organisms produced a lower mortality and less myocardial depression (P less than 0.01). S. aureus, compared to E. coli, produced higher postmortem concentrations of microorganisms and higher mortality (P less than 0.025). E. coli produced significant endotoxemia (P less than 0.01), though viable organisms (versus nonviable) resulted in higher endotoxin blood concentrations (P less than 0.05). Significant endotoxemia did not occur with S. aureus. Thus, in the absence of endotoxemia, S. aureus induced the same cardiovascular abnormalities of septic shock as E. coli. These findings indicate that structurally and functionally distinct microorganisms, with or without endotoxin, can activate a common pathway resulting in similar cardiovascular injury and mortality. PMID:2642920

  3. An experimental model of idiopathic pneumonia syndrome after bone marrow transplantation: I. The roles of minor H antigens and endotoxin.

    PubMed

    Cooke, K R; Kobzik, L; Martin, T R; Brewer, J; Delmonte, J; Crawford, J M; Ferrara, J L

    1996-10-15

    Idiopathic pneumonia syndrome (IPS) refers to diffuse, non-infectious pneumonia that occurs after allogeneic bone marrow transplantation (BMT). We have developed a model of IPS using a well-characterized murine BMT system (B10.BR-->CBA) in which lung injury after BMT can be induced by minor histocompatibility (H) antigenic differences between donor and host. Lung pathology and broncho-alveolar lavage (BAL) fluid were analyzed in transplant recipients before and after both syngeneic and allogeneic BMT. At 2 weeks after BMT, no specific pathologic abnormalities were noted; at 6 weeks, both pneumonitis and mononuclear cell infiltration around vessels and bronchioles were observed only in mice receiving allogeneic BMT. This injury was associated with elevated BAL fluid levels of endotoxin (lipopolysaccharide [LPS]), neutrophils, and tumor necrosis factor alpha. No pathologic organisms were isolated from the respiratory tract of any animal. We also tested the role of endotoxin in the development of this injury. Injection of LPS 6 weeks after transplantation caused profound lung injury only in mice with moderate graft-versus-host disease; dramatic increases in BAL neutrophils and tumor necrosis factor alpha were observed, with alveolar hemorrhage occurring in 4 of 12 of these mice but in no other group. We conclude that (1) this murine BMT system is a potentially useful model of clinical IPS; (2) minor H differences between donor and recipient can be important stimuli in the pathogenesis of IPS; and (3) endotoxin in BAL fluid is associated with lung injury, and excess endotoxin can cause the development of alveolar hemorrhage in this model. PMID:8963063

  4. Predictors of Endotoxin Levels in U.S. Housing

    PubMed Central

    Thorne, Peter S.; Cohn, Richard D.; Mav, Deepak; Arbes, Samuel J.; Zeldin, Darryl C.

    2009-01-01

    Background The relationship of domestic endotoxin exposure to allergy and asthma has been widely investigated. However, few studies have evaluated predictors of household endotoxin, and none have done so for multiple locations within homes and on a national scale. Objectives We assayed 2,552 house dust samples in a nationwide study to understand the predictors of household endotoxin in bedroom floors, family room floors, beds, kitchen floors, and family room sofas. Methods Reservoir house dust from five locations within homes was assayed for endotoxin and demographic and housing information was assessed through questionnaire and onsite evaluation of 2,456 residents of 831 homes selected to represent national demographics. We performed repeated-measures analysis of variance (rANOVA) for 37 candidate variables to identify independent predictors of endotoxin. Meteorologic data were obtained for each primary sampling unit and tested as predictors of indoor endotoxin to determine if wetter or warmer microclimates were associated with higher endotoxin levels. Results Weighted geometric mean endotoxin concentration ranged from 18.7 to 80.5 endotoxin units (EU)/mg for the five sampling locations, and endotoxin load ranged from 4,160 to 19,500 EU/m2. Bivariate analyses and rANOVA demonstrated that major predictors of endotoxin concentration were sampling location in the home, census division, educational attainment, presence of children, current dog ownership, resident-described problems with cockroaches, food debris, cockroach stains, and evidence of smoking observed by field staff. Low household income entered the model if educational attainment was removed. Conclusion Increased endotoxin in household reservoir dust is principally associated with poverty, people, pets, household cleanliness, and geography. PMID:19479019

  5. Effects of endotoxin on monoamine metabolism in the rat.

    NASA Technical Reports Server (NTRS)

    Pohorecky, L. A.; Wurtman, R. J.; Taam, D.; Fine, J.

    1972-01-01

    Examination of effects of administered endotoxin on catecholamine metabolism in the rat brain, sympathetic neurons, and adrenal medulla. It is found that endotoxin, administered intraperitoneally, lowers the norepinephrine content in peripheral sympathetic neurons and the brain, and the catecholamine content in the adrenal medulla. It also accelerates the disappearance of H3-norepinephrine from all these tissues. It is therefore suggested that the effects of endotoxin on body temperature may be mediated in part by central non-adrenergic neurons.

  6. Hemolytic-uremic syndrome: absence of circulating endotoxin.

    PubMed

    van Wieringen, P M; Monnens, L A; Bakkeren, J A

    1976-10-01

    In children with hemolytic-uremic syndrome endotoxin determinations were carried out in the peripheral circulation in order to get evidence for the hypothetical role of endotoxin in the pathogenesis of the disease. For this purpose the Limulus test was used to determine endotoxin activity in 16 patients with hemolytic-uremic syndrome. In the plasma of these patients no endotoxin could be detected above the lower detection limit of 100 pg/ml, although in all patients with septicemia due to gram-negative bacilli the test was positive. PMID:972798

  7. Lack of the Receptor for Advanced Glycation End-Products Attenuates E. coli Pneumonia in Mice

    E-print Network

    Schierup, Mikkel Heide

    Lack of the Receptor for Advanced Glycation End- Products Attenuates E. coli Pneumonia in Mice were used to determine the role of RAGE signaling in lipopolysaccharide (LPS) and E. coli induced acute of mouse soluble RAGE on E. coli injury was also investigated. Methodology/Principal Findings: C57BL/6 wild

  8. Infusion of freshly isolated autologous bone marrow derived mononuclear cells prevents endotoxin-induced lung injury in an ex-vivo perfused swine model

    PubMed Central

    2013-01-01

    Introduction The acute respiratory distress syndrome (ARDS), affects up to 150,000 patients per year in the United States. We and other groups have demonstrated that bone marrow derived mesenchymal stromal stem cells prevent ARDS induced by systemic and local administration of endotoxin (lipopolysaccharide (LPS)) in mice. Methods A study was undertaken to determine the effects of the diverse populations of bone marrow derived cells on the pathophysiology of ARDS, using a unique ex-vivo swine preparation, in which only the ventilated lung and the liver are perfused with autologous blood. Six experimental groups were designated as: 1) endotoxin alone, 2) endotoxin + total fresh whole bone marrow nuclear cells (BMC), 3) endotoxin + non-hematopoietic bone marrow cells (CD45 neg), 4) endotoxin + hematopoietic bone marrow cells (CD45 positive), 5) endotoxin + buffy coat and 6) endotoxin + in vitro expanded swine CD45 negative adherent allogeneic bone marrow cells (cultured CD45neg). We measured at different levels the biological consequences of the infusion of the different subsets of cells. The measured parameters were: pulmonary vascular resistance (PVR), gas exchange (PO2), lung edema (lung wet/dry weight), gene expression and serum concentrations of the pro-inflammatory cytokines IL-1?, TNF-? and IL-6. Results Infusion of freshly purified autologous total BMCs, as well as non-hematopoietic CD45(-) bone marrow cells significantly reduced endotoxin-induced pulmonary hypertension and hypoxemia and reduced the lung edema. Also, in the groups that received BMCs and cultured CD45neg we observed a decrease in the levels of IL-1? and TNF-? in plasma. Infusion of hematopoietic CD45(+) bone marrow cells or peripheral blood buffy coat cells did not protect against LPS-induced lung injury. Conclusions We conclude that infusion of freshly isolated autologous whole bone marrow cells and the subset of non-hematopoietic cells can suppress the acute humoral and physiologic responses induced by endotoxemia by modulating the inflammatory response, mechanisms that do not involve engraftment or trans-differentiation of the cells. These observations may have important implications for the design of future cell therapies for ARDS. PMID:23497755

  9. In vitro toxicity and interactions of environmental contaminants (Arochlor 1254 and mercury) and immunomodulatory agents (lipopolysaccharide and cortisol) on thymocytes from lake trout (Salvelinus namaycush)

    USGS Publications Warehouse

    Miller, Gregory G.; Sweet, Leonard I.; Adams, Jean V.; Omann, Geneva M.; Passino-Reader, Dora R.; Meier, Peter G.

    2002-01-01

    The immunotoxicity of chemical combinations commonly encountered by the lake trout (Salvelinus namaycush) immune system was the focus of this study. It was hypothesised that combinations of an environmental contaminant (mercuric chloride or Aroclor 1254) and an immunomodulatory agent (bacterial endotoxin or cortisol) might interact to produce a greater toxicity than that of the environmental contaminant alone at concentrations typically encountered in piscine blood and other tissues. Thus lake trout thymocytes were isolated and treated with mercuric chloride or Aroclor 1254 in the presence and absence of cortisol or lipopolysaccharide. Incubations were performed for 6 or 20h at 4A?C or 10A?C. Lipopolysaccharide did not affect the toxicity of either contaminant. In contrast, cortisol enhanced the toxicity of both environmental contaminants. Hence, stressors that lead to increased cortisol production, but not lipopolysaccharide directly, may increase the toxicity of mercury and Aroclor 1254 to lake trout thymocytes.

  10. Milk Thistle Extract and Silymarin Inhibit Lipopolysaccharide Induced Lamellar Separation of Hoof Explants in Vitro

    PubMed Central

    Reisinger, Nicole; Schaumberger, Simone; Nagl, Veronika; Hessenberger, Sabine; Schatzmayr, Gerd

    2014-01-01

    The pathogenesis of laminitis is not completely identified and the role of endotoxins (lipopolysaccharides, LPS) in this process remains unclear. Phytogenic substances, like milk thistle (MT) and silymarin, are known for their anti-inflammatory and antioxidant properties and might therefore have the potential to counteract endotoxin induced effects on the hoof lamellar tissue. The aim of our study was to investigate the influence of endotoxins on lamellar tissue integrity and to test if MT and silymarin are capable of inhibiting LPS-induced effects in an in vitro/ex vivo model. In preliminary tests, LPS neutralization efficiency of these phytogenics was determined in an in vitro neutralization assay. Furthermore, tissue explants gained from hooves of slaughter horses were tested for lamellar separation after incubation with different concentrations of LPS. By combined incubation of explants with LPS and either Polymyxin B (PMB; positive control), MT or silymarin, the influence of these substances on LPS-induced effects was assessed. In the in vitro neutralization assay, MT and silymarin reduced LPS concentrations by 64% and 75%, respectively, in comparison PMB reduced 98% of the LPS concentration. In hoof explants, LPS led to a concentration dependent separation. Accordantly, separation force was significantly decreased by 10 µg/mL LPS. PMB, MT and silymarin could significantly improve tissue integrity of explants incubated with 10 µg/mL LPS. This study showed that LPS had a negative influence on the structure of hoof explants in vitro. MT and silymarin reduced endotoxin activity and inhibited LPS-induced effects on the lamellar tissue. Hence, MT and silymarin might be used to support the prevention of laminitis and should be further evaluated for this application. PMID:25290524

  11. Anti-inflammatory effect of desoxo-narchinol-A isolated from Nardostachys jatamansi against lipopolysaccharide.

    PubMed

    Shin, Joon Yeon; Bae, Gi-Sang; Choi, Sun-Bok; Jo, Il-Joo; Kim, Dong-Goo; Lee, Dong-Sung; An, Ren-Bo; Oh, Hyuncheol; Kim, Youn-Chul; Shin, Yong Kook; Jeong, Hyun-Woo; Song, Ho-Joon; Park, Sung-Joo

    2015-12-01

    We previously reported that Nardostachys jatamansi (NJ) exhibits anti-inflammatory activity against lipopolysaccharide (LPS). However, the active compound in NJ is unknown. Therefore, here, we examined the effects of desoxo-narchinol-A (DN) isolated from NJ against LPS-induced inflammation. To demonstrate the anti-inflammatory effect of DN against LPS, we used two models; murine endotoxin shock model for in vivo model, and peritoneal macrophage responses for in vitro. In endotoxin shock model, DN was administrated intraperitoneally 1h before LPS challenge, then we evaluated mice survival rates and organ damages. Pretreatment with DN (0.05mg/kg, 0.1mg/kg, or 0.5mg/kg) dramatically reduced mortality in a murine LPS-induced endotoxin shock model. Furthermore, DN inhibited tissue injury and production of pro-inflammatory cytokines, such as interleukin (IL)-1?, IL-6, and tumor necrosis factor alpha (TNF-?), in the liver and lung. In in vitro macrophage model, we examined the inflammatory mediators and regulatory mechanisms such as mitogen-activated protein kinases (MAPKs) and nuclear factor kappa B (NF-?B). DN inhibited the production of inflammatory mediators, such as inducible nitric oxide synthase (iNOS) and its derivative nitric oxide (NO), cyclooxygenase-2 (COX-2), prostaglandin E2 (PGE2), IL-1?, IL-6 and TNF-? and H3 protein acetylation in murine peritoneal macrophages. DN also inhibited p38 activation, but not extracellular signal-regulated kinase (ERK), c-jun NH2-terminal kinase (JNK), and NF-?B. These results suggest that DN from NJ exhibits protective effects against LPS-induced endotoxin shock and inflammation through p38 deactivation. PMID:26371857

  12. Expression of lipopolysaccharide binding protein and its receptor CD14 in experimental alcoholic liver disease

    PubMed Central

    Zuo, Guo-Qing; Gong, Jian-Ping; Liu, Chang-An; Li, Shen-Wei; Wu, Xin-Chuan; Yang, Kang; Li, Yue

    2001-01-01

    AIM: To evaluate the relationship between the expression of lipopolysaccharides (LPS) binding protein (LBP) and CD14 mRNA and the severity of liver injury in alcohol-fed rats. METHODS: Twenty Wistar rats were divided into two groups: ethanol-fed group (group E) and control group (group C). Group E was fed with ethanol (5-12 g·kg¯¹·d¯¹) and group C received dextrose instead of ethanol. Rats of the two groups were sacrificed at 4 wk and 8 wk. Levels of endotoxin and alanine transaminase (ALT) in blood were measured, and liver pathology was observed under light and electronic microscopy. Expressions of LBP and CD14 mRNA in liver tissues were determined by RT-PCR analysis. RESULTS: Plasma endotoxin levels were increased more significantly in group E (129 ± 21) ng·L¯¹ and (187 ± 35) ng·L¯¹ at 4 and 8 wk than in control rats (48 ± 9) ng·L¯¹ and (53 ± 11) ng·L¯¹, respectively (P < 0.05). Mean values of plasma ALT levels were (1867 ± 250) nkat·L¯¹ and (2450 ± 367) nkat·L¯¹ in Group E. The values were increased more dramatically in ethanol-fed rats than in Group C after 4 and 8 wk. In liver section from ethanol-fed rats, there were marked pathological changes (steatosis, cell infiltration and necrosis). In ethanol-fed rats, ethanol administration led to a significant increase in LBP and CD14 mRNA levels compared with the control group (P < 0.05). CONCLUSION: Ethanol administration led to a significant increase in endotoxin levels in serum and LBP and CD14 mRNA expressions in liver tissues. The increase of LBP and CD14 mRNA expression might wake the liver more sensitive to endotoxin and liver injury. PMID:11854912

  13. Evidence for the involvement of a plasma kallikrein-kinin system in the immediate hypotension produced by endotoxin in anaesthetized rats.

    PubMed Central

    Katori, M.; Majima, M.; Odoi-Adome, R.; Sunahara, N.; Uchida, Y.

    1989-01-01

    1. In vitro incubation of normal rat plasma with endotoxin from E. coli (3-10 mg ml-1) in the incubation mixture) caused a dose-dependent increase in levels of free kinin and plasma kallikrein in the presence of o-phenanthroline, together with a mirror-image, dose-dependent decrease in the residual levels of the precursors, plasma prekallikrein and high-molecular-weight kininogen. Low-molecular-weight kininogen levels were not modified. 2. Intravenous injection of endotoxin (3-30 mg kg-1) into the femoral vein of anaesthetized rats resulted in dose-dependent hypotension. In blood collected up to 15 min after injection, the levels of prekallikrein and high-molecular-weight kininogen in plasma were decreased while levels of the active forms, plasma kallikrein and free kinin, showed a transient increase in the blood 1 min after administration of endotoxin. 3. A degradation product of bradykinin, des-Phe8-Arg9-bradykinin, as measured by a newly developed enzyme immunoassay, was detectable up to 5 min after administration of endotoxin. 4. Intravenous infusion of soybean trypsin inhibitor inhibited both the formation of bradykinin and des-Phe8-Arg9-bradykinin and the initial hypotension. 5. It can be concluded from our results that plasma prekallikrein is activated in the blood immediately after administration of endotoxin to rats and that bradykinin is a major cause of the immediate hypotension. PMID:2692754

  14. Removal of lipopolysaccharides from protein-lipopolysaccharide complexes by nonflammable solvents.

    PubMed

    Lin, Miao-Fang; Williams, Christie; Murray, Michael V; Ropp, Philip A

    2005-02-25

    During the recovery of recombinant proteins from gram negative bacteria, many of the methods used to extract proteins from cells release lipopolysaccharides (LPS, endotoxin) along with the protein of interest. In many instances, LPS will co-purify with the target protein due to specific or non-specific protein-LPS interactions. We have investigated the ability of alkanediols to effect the separation of LPS from protein-LPS complexes while the complexes are immobilized on ion exchange chromatographic resins. Proteins were complexed with fluorescently labeled LPS and bound to ion exchange resin. Alkanediol washes of the resins were preformed and the proteins eluted. Column eluates were monitored for LPS and protein by fluorescence and UV spectroscopy, respectively. Alkanediols were effective agents for dissociating LPS from protein-LPS complexes. The efficiency of LPS removal increased with increasing alkanediol chain length. The 1,2-alkanediol isomers were more effective than terminal alkanediol isomers in the separation of LPS from protein-LPS complexes, while the separation of LPS from protein-LPS complexes was more efficient on cation exchangers than on anion exchangers. In addition, it was noted during these investigations that the 1,2-alkanediols increased the retention time of the proteins on the ion exchange resins. Alkanediols provide a safer alternative to the use of other organics such as alcohols or acetonitrile for the separation of LPS from protein due to their lower toxicity and decreased inflammability. In addition, they are less costly than many of the detergents that have been used for similar purposes. PMID:15664347

  15. Endotoxin stimulates expression of the murine urokinase receptor gene in vivo.

    PubMed Central

    Almus-Jacobs, F.; Varki, N.; Sawdey, M. S.; Loskutoff, D. J.

    1995-01-01

    The regulation of urokinase receptor (u-PAR) gene expression during endotoxemia was studied in vivo with a murine model system. Northern blot analysis demonstrated relatively high levels of u-PAR mRNA in mouse placenta, with intermediate levels in lung and spleen and very low levels in heart and kidney. No u-PAR mRNA could be detected in liver, gut, thymus, brain, or skeletal muscle. Intraperitoneal injection of endotoxin (lipopolysaccharide) increased the steady-state levels of u-PAR mRNA in most tissues examined. The greatest induction (sevenfold) was observed in the lung at 1 hour after injection. The cellular localization of u-PAR mRNA was assessed by in situ hybridization. In control mice, u-PAR mRNA was detected primarily in alveolar macrophages of the lung and lymphocytes of the spleen and thymus, although a specific signal was also present in other cell types. In general, endothelial cells lacked detectable u-PAR mRNA. The induction of u-PAR mRNA by lipopolysaccharide was apparent within 30 minutes and was localized to tissue macrophages, lymphocytes, and endothelial cells lining arteries and veins. At later times (1 to 3 hours), specialized epithelial cells present in gastrointestinal tract, bile ducts, and uterus were also positive for u-PAR mRNA. Induction of u-PAR in vivo by lipopolysaccharide may facilitate the extravasation and migration of leukocytes during inflammation. Images Figure 1 Figure 4 Figure 2 Figure 3 Figure 5 Figure 6 Figure 7 Figure 8 Figure 9 PMID:7677180

  16. E. Coli

    MedlinePLUS

    ... this: Main Content Area E. coli? Hundreds of Escherichia coli ( E. coli ) strains are harmless, including those that ... fenugreek seeds used to grow sprouts. Because STEC E. coli infections can be spread from person-to-person, the ...

  17. EFFECTS OF LIME (CAO) ON THE ENDOTOXIN LEVELS OF BIOSOLIDS

    EPA Science Inventory

    Lime addition is a common practice for treating biosolids in order to meet EPA 503 requirements for land application. Since this treatment kills the majority of microorganisms, will it increase the level of endotoxins present in biosolids? And, if endotoxin levels are increased, ...

  18. Evaluation of endotoxin retention by adsorptive-based filtration media.

    PubMed

    O'Brien, Thomas P; Conway, Robert; Chen, Hsiao-Lin; Buckland, Kim

    2007-01-01

    Control of endotoxin contamination is an important issue in pharmaceutical and bioprocess manufacturing. Endotoxins can contaminate process intermediates used in pharmaceutical formulations, aqueous- and non-aqueous-based CIP fluids used in equipment and vial cleaning, and process fluids such as buffers used for chromatographic elution, diafiltration, and suspension of therapeutic protein-based drugs. A study was undertaken to evaluate the effectiveness of adsorptive-based depth and membrane filtration media in removing suspended endotoxin. The following variables were examined in order to determine their effects on endotoxin reduction: absorptive media type, residence time (flux), challenge solution pH, and interferences in endotoxin reduction as the result of challenge solution composition-water for injection, process buffer, and the presence of protein. The endotoxin removal capacities of the various media studied were also determined. The results of the study demonstrated differences in the effect on endotoxin removal of the variables evaluated. In addition, the results provide a strategy for conducting studies to select and validate an appropriate adsorptive filter media for control of endotoxin contamination. PMID:17479715

  19. Determinants that increase the serum resistance of Escherichia coli.

    PubMed Central

    Taylor, P W; Robinson, M K

    1980-01-01

    The rfb locus, determining biosynthesis of O8-specific lipopolysaccharide side chains, was transferred to a rough mutant of Escherichia coli; recombinants producing a complete lipopolysaccharide were more resistant to the complement-mediated bactericidal action of human serum than the rough recipient. Inheritance of the his-linked genes for K27 antigen production did not alter the response to serum. The serum resistance of strains carrying O8 side chains, but not of strains with incomplete lipopolysaccharides, was further increased by inheritance of plasmids R1 and NR1.20 PMID:6995340

  20. Visualization and analysis of lipopolysaccharide distribution in binary phospholipid bilayers

    SciTech Connect

    Henning, Maria Florencia; Sanchez, Susana; Bakas, Laura; Departamento de Ciencias Biologicas, Facultad de Ciencias Exactas, UNLP, Calles 47 y 115, 1900 La Plata

    2009-05-22

    Lipopolysaccharide (LPS) is an endotoxin released from the outer membrane of Gram-negative bacteria during infections. It have been reported that LPS may play a role in the outer membrane of bacteria similar to that of cholesterol in eukaryotic plasma membranes. In this article we compare the effect of introducing LPS or cholesterol in liposomes made of dipalmitoylphosphatidylcholine/dioleoylphosphatidylcholine on the solubilization process by Triton X-100. The results show that liposomes containing LPS or cholesterol are more resistant to solubilization by Triton X-100 than the binary phospholipid mixtures at 4 {sup o}C. The LPS distribution was analyzed on GUVs of DPPC:DOPC using FITC-LPS. Solid and liquid-crystalline domains were visualized labeling the GUVs with LAURDAN and GP images were acquired using a two-photon microscope. The images show a selective distribution of LPS in gel domains. Our results support the hypothesis that LPS could aggregate and concentrate selectively in biological membranes providing a mechanism to bring together several components of the LPS-sensing machinery.

  1. Helicobacter pylori lipopolysaccharide hinders polymorphonuclear leucocyte apoptosis.

    PubMed

    Hofman, V; Ricci, V; Mograbi, B; Brest, P; Luciano, F; Boquet, P; Rossi, B; Auberger, P; Hofman, P

    2001-03-01

    A prominent histologic feature of Helicobacter pylori infection is a dense infiltration of polymorphonuclear leukocytes (PMNL) in gastric mucosa. H. pylori lipopolysaccharide (LPS) has been recognized as a primary virulence factor evoking acute mucosal inflammatory reaction. Previous works have shown that H. pylori LPS immunologic activities are lower than those of enterobacterial LPS. However, the effect of H. pylori LPS on spontaneous PMNL apoptosis, and mechanisms by which this H. pylori LPS may promote PMNL survival remain to be established. In this study, we investigated, by both morphologic and biochemical approaches, the action of H. pylori LPS on PMNL apoptosis in vitro, using broth culture filtrates (BCF) of H. pylori strains with different genotypes. We found that BCF from H. pylori caused a significant delay in spontaneous PMNL apoptosis and this delay was independent of the VacA, cag pathogenicity island and urease status. We demonstrated that LPS in BCF is responsible for this effect because it was abrogated by the LPS antagonist B287 (a synthetic analog of Rhodobactersphaeroides lipid A). Moreover, BCF from H. pylori induced P42/44MAP kinase activation in PMNL. Similar results were obtained with BCF of an Escherichia coli strain. Taken together these data suggest that longer survival of PMNL induced by H. pylori LPS may increase gastric epithelium injury in H. pylori-associated diseases. PMID:11310830

  2. Low Endotoxic Potential of Legionella pneumophila Lipopolysaccharide due to Failure of Interaction with the Monocyte Lipopolysaccharide Receptor CD14

    PubMed Central

    Neumeister, B.; Faigle, M.; Sommer, M.; Zähringer, U.; Stelter, F.; Menzel, R.; Schütt, C.; Northoff, H.

    1998-01-01

    Legionella pneumophila, a gram-negative bacterium causing Legionnaires’ disease and Pontiac fever, was shown to be highly reactive in in vitro gelation of Limulus lysate but not able to induce fever and the local Shwartzman reaction in rabbits and mice. We analyzed the capacity of purified L. pneumophila lipopolysaccharide (LPS-Lp) to induce activation of the human monocytic cell line Mono Mac 6, as revealed by secretion of proinflammatory cytokines and desensitization to subsequent LPS stimulation. We showed that despite normal reactivity of LPS-Lp in the Limulus amoebocyte lysate assay, induction of cytokine secretion in Mono Mac 6 cells and desensitization to an endotoxin challenge required LPS-Lp concentrations 1,000 times higher than for LPS of Salmonella enterica serovar Minnesota. Therefore, we examined the interaction of LPS-Lp with the LPS receptor CD14. We demonstrated that LPS-Lp did not bind to membrane-bound CD14 expressed on transfected CHO cells, nor did it react with soluble CD14. Our results suggest that the low endotoxic potential of LPS-Lp is due to a failure of interaction with the LPS receptor CD14. PMID:9712761

  3. Endotoxin Elimination in Patients with Septic Shock: An Observation Study.

    PubMed

    Adamik, Barbara; Zielinski, Stanislaw; Smiechowicz, Jakub; Kübler, Andrzej

    2015-12-01

    To evaluate the effectiveness of endotoxin elimination with an adsorption column in patients with septic shock and endotoxemia. The elimination therapy was guided by a new bedside method of measuring endotoxin activity (EA). Intensive care unit (ICU) patients with septic shock and suspected Gram-negative infection were consecutively added to the study group within the first 24 h. Endotoxin elimination was performed using hemoperfusion with the Alteco LPS Adsorber. The primary endpoint was improvement in organ function within the first 24 h of treatment. A secondary objective was to assess the usefulness of a new method of measuring EA to help guide endotoxin elimination therapy. Out of 64 patients 18 had a high baseline EA [0.70 EA units (0.66-0.77)]. Those patients had endotoxin elimination treatment in addition to conventional medical therapy. At 24 h after endotoxin elimination, the EA had decreased to 0.56 EA units (0.43-0.77), (p = 0.005); MAP increased from 69 (62-80) to 80 mm Hg (68-88), (p = 0.002), and noradrenaline use decreased from 0.28 (0.15-0.80) to 0.1 ?g/kg/min (0.00-0.70) at the same time (p = 0.04). The SOFA score had decreased from 11 (9-15) to 9 (7-14) points 24 h after endotoxin elimination (p = 0.01) with a median delta SOFA -2 points. Endotoxin elimination did not have a significant effect on the ICU length of stay or ICU mortality. Effective endotoxin elimination resulted in a significant improvement in hemodynamic parameters and of organ function. The application of the EA assay was useful for the bedside monitoring of endotoxemia in critically ill ICU patients. PMID:26093653

  4. Estrogen receptor ? mediates the effects of notoginsenoside R1 on endotoxin-induced inflammatory and apoptotic responses in H9c2 cardiomyocytes.

    PubMed

    Zhong, Lei; Zhou, Xing-Lu; Liu, Yan-Song; Wang, Yi-Min; Ma, Fei; Guo, Bao-Liang; Yan, Zhao-Qi; Zhang, Qing-Yuan

    2015-07-01

    Estrogen receptors (ERs) are important for preventing endotoxin-induced myocardial dysfunction. Therefore, plant-derived phytoestrogens, which target ERs may also affect endotoxin-induced toxicity in cardiomyocytes. Our previous study revealed that notoginsenoside-R1 (NG-R1), a predominant phytoestrogen from Panax notoginseng, protects against cardiac dysfunction. However, the effects of NG-R1 on cardiomyocytes and the precise cellular/molecular mechanisms underlying its action remain to be elucidated. In the present study, pretreatment with NG-R1 suppressed the lipopolysaccharide (LPS)-induced degradation of inhibitor of nuclear factor-?B (NF-?B) ?, the activation of NF-?B and caspase-3, and the subsequent myocardial inflammatory and apoptotic responses in H9c2 cardiomyocytes. An increase in the mRNA and protein expression of ER? was also observed in the NG-R1-treated cardiomyocytes. However, the expression pattern of ER? remained unaltered. Furthermore, the cardioprotective properties of NG-R1 against LPS-induced apoptosis and the inflammatory response in cardiomyocytes were attenuated by ICI 182780, a non-selective ER? antagonist, and methyl-piperidino-pyrazole, a selective ER? antagonist. These findings suggested that NG-R1 reduced endotoxin-induced cardiomyocyte apoptosis and the inflammatory response via the activation of ER?. Therefore, NG-R1 exerted direct anti-inflammatory and anti-apoptotic effects on the cardiomyocytes, representing a potent agent for the treatment of myocardial inflammation during septic shock. PMID:25738436

  5. [Biochemistry, molecular mechanism of action and biological effects of endotoxin].

    PubMed

    Burgmann, H; Breyer, S

    1995-01-01

    This review is a brief attempt at providing an overview of a subject of enormous complexity-endotoxins and the mediators associated with its biological effects. More specifically it deals with biochemistry and biology of endotoxin, detection of endotoxin with the Limulus amebocyte lysate test, the molecular mechanisms and biological effects, and in the last part with future aspects of therapeutical strategies. It seems certain that the subject will become even more complex and possibly controversial as scientific knowledge further involves. However, because of the high mortality rate of patients suffering from gram-negative sepsis all efforts have to be made to find effective therapeutical strategies. PMID:7543712

  6. [Loss of contractile stability induced by phenylephrine and endothelin in the aorta of rats treated with endotoxin].

    PubMed

    Auguet, M; Delaflotte, S; Chabrier, P E; Braquet, P

    1990-07-01

    The alterations of vascular reactivity in endotoxemia were investigated using the aorta from intraperitoneally endotoxin-injected rats (E. Coli 0111: B4; 10 mg/kg). After 3 hours, rings were removed and isometric contractions recorded. Using single maximal agonist concentration, similar contractions were observed in sham and shocked preparations for phenylephrine (PE), endothelin (ET-1) and phorbol 12, 13 dibutyrate (PDB) but not for KCl. Nevertheless, contraction elicited by PE lost tonicity (105 min observation). This fact was not due to endothelium, prostaglandins (since indomethacin and aspirin were ineffective) PE degradation (since medium contained, propranolol, hydrocortisone acetate, cocaine and EDTA) or excitation-contraction coupling fading (since contraction was restored by other agonists) but may involve synthesis of protein (since cycloheximide significantly antagonized this phenomenon). This loss of tonicity was also observed with ET-1 but was less pronounced with KCl and PDB. In conclusion, endotoxin induced impairment of vascular reactivity may occur through different pathways: contractile events (e.g. calcium influx as exemplified by KCl) and receptor events (loss of tonicity and/or desensitization as exemplified by PE and ET-1) from the different agonists tested, PDB, which activates the protein kinase C, was the less affected by endotoxin. PMID:2124456

  7. Comparison of lipopolysaccharide structures of Bordetella pertussis clinical isolates from pre- and post-vaccine era.

    PubMed

    Albitar-Nehme, Sami; Basheer, Soorej M; Njamkepo, Elisabeth; Brisson, Jean-Robert; Guiso, Nicole; Caroff, Martine

    2013-08-30

    Endotoxins are lipopolysaccharides (LPS), and major constituents of the outer membrane of Gram-negative bacteria. Bordetella pertussis LPS were the only major antigens, of this agent of whooping-cough, that were not yet analyzed on isolates from the pre- and post-vaccination era. We compared here the LPS structures of four clinical isolates with that of the vaccine strain BP 1414. All physico-chemical analyses, including SDS-PAGE, TLC, and different MALDI mass spectrometry approaches were convergent. They helped demonstrating that, on the contrary to some other B. pertussis major antigens, no modification occurred in the dodecasaccharide core structure, as well as in the whole LPS molecules. These results are rendering these major antigens good potential vaccine components. Molecular modeling of this conserved LPS structure also confirmed the conclusions of previous experiments leading to the production of anti-LPS monoclonal antibodies and defining the main epitopes of these major antigens. PMID:23731797

  8. E. Coli

    MedlinePLUS

    ... E. coli is short for the medical term Escherichia coli . The strange thing about these bacteria — and lots ... cause a very serious infection. Someone who has E. coli infection may have these symptoms: bad stomach cramps and ...

  9. Pellino-3 promotes endotoxin tolerance and acts as a negative regulator of TLR2 and TLR4 signaling.

    PubMed

    Murphy, Michael B; Xiong, Yanbao; Pattabiraman, Goutham; Manavalan, Tissa T; Qiu, Fu; Medvedev, Andrei E

    2015-12-01

    Development of endotoxin tolerance in macrophages during sepsis reprograms Toll-like receptor 4 signaling to inhibit proinflammatory cytokines without suppressing anti-inflammatory and antimicrobial mediators and protects the host from excessive inflammation and tissue damage. However, endotoxin tolerance renders septic patients immunocompromised and unable to control secondary infections. Although previous studies have revealed the importance of several negative regulators of Toll-like receptor signaling in endotoxin tolerance, the role of Pellino proteins has not been addressed. The present report shows that the induction of endotoxin tolerance in vivo in mice and in vitro in human monocytes and THP-1 and MonoMac-6 macrophages increases the expression of Pellino-3. Overexpression of Pellino-3 in human embryonic kidney 293/Toll-like receptor 2 or 293/Toll-like receptor 4/myeloid differentiation factor-2 cells inhibited Toll-like receptor 2/4-mediated activation of nuclear factor-?B and induction of CXCL-8 mRNA, and Pellino-3 ablation increased these responses. Pellino-3-deficient THP-1 cells had elevated Toll-like receptor 2/4-driven tumor necrosis factor-?, interleukin-6 mRNA, and Toll-like receptor 4-driven CCL5 gene expression in response to Toll-like receptor agonists and heat-killed Escherichia coli and Staphylococcus aureus, cytokines controlled by the MyD88 and Toll-interleukin-1R domain-containing protein inducing interferon-?-mediated pathways, respectively. In addition, deficiency in Pellino-3 slightly increased phagocytosis of heat-killed bacteria. Transfected Pellino-3 inhibited nuclear factor-?B activation driven by overexpression of MyD88, TIR domain-containing adapter inducing interferon-?, interleukin-1R-associated kinase-1, and tumor necrosis factor receptor activator of nuclear factor-?B-binding kinase-1, TGF-?-activated kinase 1, and tumor necrosis factor receptor-associated factor-6, and inhibited interleukin-1R-associated kinase 1 modifications and tumor necrosis factor receptor activator of nuclear factor-?B-binding kinase 1 phosphorylation. Finally, Pellino-3 ablation in THP-1 decreased the extent of endotoxin tolerization. Thus, Pellino-3 is involved in endotoxin tolerance and functions as a negative regulator of Toll-like receptor 2/4 signaling. PMID:26310831

  10. Immunohistochemical staining for endotoxin using horseshoe crab factor C in fecal peritonitis.

    PubMed

    Nakao, A; Yasui, M; Shen, S; Takagi, H

    1995-01-01

    The object of the present study was to apply a new immunohistochemical staining method to the in vivo determination of endotoxin localization. The immunohistochemical staining method requires factor C (an initiation factor in the Limulus clotting system which is mediated by endotoxin) as a specific ligand of endotoxin, and a newly developed murine monoclonal antibody to factor C. The blood endotoxin level and endotoxin localization in the rat were determined before and at 6, 12 and 24 h after intraperitoneal injection of 0.25 g/kg of fresh rat feces. The greatest blood endotoxin level was achieved at 12 h after the injection, and uptake of endotoxin was evident in Kupffer cells in the liver at 24 h after the injection. There has been no report on determining endotoxin localization in cases of endotoxemia attributed to fecal peritonitis. This new immunohistochemical staining method for determining endotoxin localization will contribute to the histopathological diagnosis of endotoxemia in humans. PMID:7544288

  11. Interactions of a designed peptide with lipopolysaccharide: Bound conformation and anti-endotoxic activity

    SciTech Connect

    Bhunia, Anirban; Chua, Geok Lin; Domadia, Prerna N.; Warshakoon, Hemamali; Cromer, Jens R.; David, Sunil A.; Bhattacharjya, Surajit

    2008-05-09

    Designed peptides that would selectively interact with lipopolysaccharide (LPS) or endotoxin and fold into specific conformations could serve as important scaffolds toward the development of antisepsis compounds. Here, we describe solution structure of a designed amphipathic peptide, H{sub 2}N-YVKLWRMIKFIR-CONH{sub 2} (YW12D) in complex with endotoxin as determined by transferred nuclear Overhauser effect spectroscopy. The conformation of the isolated peptide is highly flexible, but undergoes a dramatic structural stabilization in the presence of LPS. Structure calculations reveal that the peptide presents two amphipathic surfaces in its bound state to LPS whereby each surface is characterized by two positive charges and a number of aromatic and/or aliphatic residues. ITC data suggests that peptide interacts with two molecules of lipid A. In activity assays, YW12D exhibits neutralization of LPS toxicity with very little hemolysis of red blood cells. Structural and functional properties of YW12D would be applicable in designing low molecular weight non-toxic antisepsis molecules.

  12. Abnormal lipopolysaccharide binding protein as marker of gastrointestinal inflammation in Parkinson disease

    PubMed Central

    Pal, Gian D.; Shaikh, Maliha; Forsyth, Christopher B.; Ouyang, Bichun; Keshavarzian, Ali; Shannon, Kathleen M.

    2015-01-01

    Objective: An inflammation-driven model of PD has been proposed based on the endotoxin lipopolysaccaride (LPS), a potential source of inflammation in the gastrointestinal system linked to neurotoxicity. Systemic exposure to bacterial endotoxin (LPS) can be determined by measuring plasma LPS binding protein (LBP). We aimed to evaluate whether lipopolysaccharide binding protein (LBP) can be used to distinguish PD subjects from control subjects and to assess whether LBP levels correlate with PD disease severity. Methods: We measured plasma LBP (ng/ml) using an ELISA kit in 94 PD subjects of various stages and 97 control subjects. Disease severity was assessed using the UPDRS and Hoehn and Yahr staging. The LBP level between the PD and control groups was compared using analysis of covariance. Spearman correlation was used to explore the relationship between LBP level and disease severity. Results: The mean LBP level in PD subjects (n = 94) was significantly different from control subjects (n = 95, p = 0.018). In PD subjects, we did not find a correlation between mean LBP level and disease severity. Conclusions: Our data suggests that LBP is one GI biomarker related to LPS induced neurotoxicity. However, there was significant variability in LBP levels within the PD and control groups, limiting its utility as a stand-alone biomarker. This study supports the role of LPS induced neurotoxicity in PD and further exploration of this pathway may be useful in developing sensitive and specific biomarkers for PD. PMID:26388718

  13. Interactions between chensinin-1, a natural antimicrobial peptide derived from Rana chensinensis, and lipopolysaccharide.

    PubMed

    Dong, Weibing; Sun, Yue; Shang, Dejing

    2015-12-01

    Lipopolysaccharide (LPS) plays a critical role in the pathogenesis of sepsis caused by gram-negative bacterial infections. Therefore, LPS-neutralizing molecules would have important clinical applications. Chensinin-1, a novel antimicrobial peptide with atypical structural features, was found in the skin secretions of the Chinese brown frog Rana chensinensis. To understand the role of LPS in the bacterial susceptibility to chensinin-1 and to investigate its anti-endotoxin effects, the interactions of chensinin-1 with LPS were investigated in this study using circular dichroism, in situ IR, isothermal titration calorimetry, and zeta potential. This study is the first to use in situ IR spectroscopy to evaluate the secondary structural changes of this peptide. The capacity of chensinin-1 to block the LPS-dependent cytokine secretion of macrophages was also investigated. Our results show that chensinin-1 can form ?-helical structures in LPS suspensions. LPS can affect the antimicrobial activity of chensinin-1, and chensinin-1 was able to mitigate the effects of LPS. These data may facilitate the development of antimicrobial peptides with potent antimicrobial and anti-endotoxin activities. PMID:26340228

  14. Lipopolysaccharide Inhibits the Channel Activity of the P2X7 Receptor

    PubMed Central

    Leiva-Salcedo, Elias; Coddou, Claudio; Rodríguez, Felipe E.; Penna, Antonello; Lopez, Ximena; Neira, Tanya; Fernández, Ricardo; Imarai, Mónica; Rios, Miguel; Escobar, Jorge; Montoya, Margarita; Huidobro-Toro, J. Pablo; Escobar, Alejandro; Acuña-Castillo, Claudio

    2011-01-01

    The purinergic P2X7 receptor (P2X7R) plays an important role during the immune response, participating in several events such as cytokine release, apoptosis, and necrosis. The bacterial endotoxin lipopolysaccharide (LPS) is one of the strongest stimuli of the immune response, and it has been shown that P2X7R activation can modulate LPS-induced responses. Moreover, a C-terminal binding site for LPS has been proposed. In order to evaluate if LPS can directly modulate the activity of the P2X7R, we tested several signaling pathways associated with P2X7R activation in HEK293 cells that do not express the TLR-4 receptor. We found that LPS alone was unable to induce any P2X7R-related activity, suggesting that the P2X7R is not directly activated by the endotoxin. On the other hand, preapplication of LPS inhibited ATP-induced currents, intracellular calcium increase, and ethidium bromide uptake and had no effect on ERK activation in HEK293 cells. In splenocytes-derived T-regulatory cells, in which ATP-induced apoptosis is driven by the P2X7R, LPS inhibited ATP-induced apoptosis. Altogether, these results demonstrate that LPS modulates the activity of the P2X7R and suggest that this effect could be of physiological relevance. PMID:21941410

  15. Lipopolysaccharide inhibits the channel activity of the P2X7 receptor.

    PubMed

    Leiva-Salcedo, Elias; Coddou, Claudio; Rodríguez, Felipe E; Penna, Antonello; Lopez, Ximena; Neira, Tanya; Fernández, Ricardo; Imarai, Mónica; Rios, Miguel; Escobar, Jorge; Montoya, Margarita; Huidobro-Toro, J Pablo; Escobar, Alejandro; Acuña-Castillo, Claudio

    2011-01-01

    The purinergic P2X7 receptor (P2X7R) plays an important role during the immune response, participating in several events such as cytokine release, apoptosis, and necrosis. The bacterial endotoxin lipopolysaccharide (LPS) is one of the strongest stimuli of the immune response, and it has been shown that P2X7R activation can modulate LPS-induced responses. Moreover, a C-terminal binding site for LPS has been proposed. In order to evaluate if LPS can directly modulate the activity of the P2X7R, we tested several signaling pathways associated with P2X7R activation in HEK293 cells that do not express the TLR-4 receptor. We found that LPS alone was unable to induce any P2X7R-related activity, suggesting that the P2X7R is not directly activated by the endotoxin. On the other hand, preapplication of LPS inhibited ATP-induced currents, intracellular calcium increase, and ethidium bromide uptake and had no effect on ERK activation in HEK293 cells. In splenocytes-derived T-regulatory cells, in which ATP-induced apoptosis is driven by the P2X7R, LPS inhibited ATP-induced apoptosis. Altogether, these results demonstrate that LPS modulates the activity of the P2X7R and suggest that this effect could be of physiological relevance. PMID:21941410

  16. The Transfer of Endotoxin Induced Immunity from Hens to Poults

    PubMed Central

    Truscott, R. B.; Friars, G. W.

    1972-01-01

    Turkey hens were vaccinated six times with Salmonella typhimurium endotoxin prior to and during their egg production cycle. The resultant poults possessed a significant degree of immunity to challenge with S. typhimurium. PMID:4258548

  17. A rapid test for endotoxin in whole blood.

    PubMed

    Rylatt, D; Wilson, K; Kemp, B E; Elms, M J; Manickavasagam, B; Shi, W; Cox, A; McArthur, M J; O'Hara, J; Corbett, M E

    1995-01-01

    A rapid whole blood agglutination test has been developed for the detection of endotoxin. The test reagent consists of polymyxin B (PmB) conjugated to the Fab fragment of the anti-glycophorin antibody 1C3/86. After addition of reagent to whole blood, red cell agglutination occurs within two minutes in samples from endotoxaemic patients or with the addition of either whole Gram negative bacteria, supernatants from Gram negative bacterial cultures or purified endotoxin. In clinical samples there was a strong correlation (r = 0.83) between the strength of agglutination and the level of endotoxin measured by the Limulus amaebolysate test (LAL). The prospect of a rapid and accurate test for endotoxin may enable better clinical management of Gram negative sepsis. PMID:8524932

  18. 40 CFR 180.1108 - Delta endotoxin of Bacillus thuringiensis variety San Diego encapsulated into killed Pseudomonas...

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...2013-07-01 2013-07-01 false Delta endotoxin of Bacillus thuringiensis variety...Exemptions From Tolerances § 180.1108 Delta endotoxin of Bacillus thuringiensis variety...the requirement of a tolerance. The delta endotoxin of Bacillus thuringiensis...

  19. 40 CFR 180.1108 - Delta endotoxin of Bacillus thuringiensis variety San Diego encapsulated into killed Pseudomonas...

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ...2012-07-01 2012-07-01 false Delta endotoxin of Bacillus thuringiensis variety...Exemptions From Tolerances § 180.1108 Delta endotoxin of Bacillus thuringiensis variety...the requirement of a tolerance. The delta endotoxin of Bacillus thuringiensis...

  20. 40 CFR 180.1108 - Delta endotoxin of Bacillus thuringiensis variety San Diego encapsulated into killed Pseudomonas...

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...2014-07-01 2014-07-01 false Delta endotoxin of Bacillus thuringiensis variety...Exemptions From Tolerances § 180.1108 Delta endotoxin of Bacillus thuringiensis variety...the requirement of a tolerance. The delta endotoxin of Bacillus thuringiensis...

  1. 40 CFR 180.1108 - Delta endotoxin of Bacillus thuringiensis variety San Diego encapsulated into killed Pseudomonas...

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...2010-07-01 2010-07-01 false Delta endotoxin of Bacillus thuringiensis variety...Exemptions From Tolerances § 180.1108 Delta endotoxin of Bacillus thuringiensis variety...the requirement of a tolerance. The delta endotoxin of Bacillus thuringiensis...

  2. 40 CFR 180.1108 - Delta endotoxin of Bacillus thuringiensis variety San Diego encapsulated into killed Pseudomonas...

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...2011-07-01 2011-07-01 false Delta endotoxin of Bacillus thuringiensis variety...Exemptions From Tolerances § 180.1108 Delta endotoxin of Bacillus thuringiensis variety...the requirement of a tolerance. The delta endotoxin of Bacillus thuringiensis...

  3. Coarse particulate matter and airborne endotoxin within wood stove homes.

    PubMed

    McNamara, M; Thornburg, J; Semmens, E; Ward, T; Noonan, C

    2013-12-01

    Emissions from indoor biomass burning are a major public health concern in developing areas of the world. Less is known about indoor air quality, particularly airborne endotoxin, in homes burning biomass fuel in residential wood stoves in higher income countries. A filter-based sampler was used to evaluate wintertime indoor coarse particulate matter (PM????.?) and airborne endotoxin (EU/m³, EU/mg) concentrations in 50 homes using wood stoves as their primary source of heat in western Montana. We investigated number of residents, number of pets, dampness (humidity), and frequency of wood stove usage as potential predictors of indoor airborne endotoxin concentrations. Two 48-h sampling events per home revealed a mean winter PM????.? concentration (± s.d.) of 12.9 (± 8.6) ?g/m³, while PM?.? concentrations averaged 32.3 (± 32.6) ?g/m³. Endotoxin concentrations measured from PM????.? filter samples were 9.2 (± 12.4) EU/m³ and 1010 (± 1524) EU/mg. PM????.? and PM?.? were significantly correlated in wood stove homes (r = 0.36, P < 0.05). The presence of pets in the homes was associated with PM????.? but not with endotoxin concentrations. Importantly, none of the other measured home characteristics was a strong predictor of airborne endotoxin, including frequency of residential wood stove usage. PMID:23551341

  4. Validity of the endotoxin assay in post surgical patients.

    PubMed

    Büller, H R; ten Cate, J W; Sturk, A; Thomas, L L

    1985-01-01

    In a prospective study 56 patients were studied after major surgery for 10 days to correlate endotoxemia with bacteremia and clinical septicemia. Endotoxemia was detected with a quantitative plasma endotoxin assay using limulus lysate and a chromogenic substrate. Clinical septicemia was defined using a set of predetermined criteria. In 29 patients both bacterial cultures and endotoxin assays were negative. One patient showed clinical signs of septicemia. In 14 patients, low grade endotoxemia (mean 47 +/- 15 pg/ml) was observed in the first three days after surgery. Only three of these patients also showed positive endotoxin tests after this period. Corresponding blood cultures were frequently negative (81%) most likely due to prior and concurrent antibiotic prophylaxis. Two endotoxin positive patients had clinical signs of septicemia. In a total of 16 patients, including two patients from the former group endotoxemia (mean 56 +/- 21 pg/ml) was noted beyond the third post-operative day. Samples for blood cultures collected simultaneously were positive for gram negative bacilli in six patients. Clinical septicemia was present in 12 of the 16 patients. The positive and negative predictive value of the endotoxin test for bacteremia and/or septicemia after the third day of surgery for all patients was found to be 75% and 98% respectively. The results of this small prospective study in surgical patients suggest that this rapid endotoxin test is a useful clinical adjunct for both the detection and exclusion of gram negative bacteremia/septicemia. PMID:4048215

  5. An Anti-Interleukin-2 Receptor Drug Attenuates T- Helper 1 Lymphocytes-Mediated Inflammation in an Acute Model of Endotoxin-Induced Uveitis

    PubMed Central

    Navea, Amparo; Almansa, Inmaculada; Muriach, María; Bosch-Morell, Francisco

    2014-01-01

    The aim of the present study was to evaluate the anti-inflammatory efficacy of Daclizumab, an anti-interleukin-2 receptor drug, in an experimental uveitis model upon a subcutaneous injection of lipopolysaccharide into Lewis rats, a valuable model for ocular acute inflammatory processes. The integrity of the blood-aqueous barrier was assessed 24 h after endotoxin-induced uveitis by evaluating two parameters: cell count and protein concentration in aqueous humors. The histopathology of all the ocular structures (cornea, lens, sclera, choroid, retina, uvea, and anterior and posterior chambers) was also considered. Enzyme-linked immunosorbent assays of the aqueous humor samples were performed to quantify the levels of the different chemokine and cytokine proteins. Similarly, a biochemical analysis of oxidative stress-related markers was also assessed. The inflammation observed in the anterior chamber of the eyes when Daclizumab was administered with endotoxin was largely prevented since the aqueous humor protein concentration substantially lowered concomitantly with a significant reduction in the uveal and vitreous histopathological grading. Th1 lymphocytes-related cytokines, such as Interleukin-2 and Interferon-?, also significantly reduced with related anti-oxidant systems recovery. Daclizumab treatment in endotoxin-induced uveitis reduced Th1 lymphocytes-related cytokines, such as Interleukin-2 and Interferon gamma, by about 60–70% and presented a preventive role in endotoxin-induced oxidative stress. This antioxidant protective effect of Daclizumab may be related to several of the observed Daclizumab effects in our study, including IL-6 cytokine regulatory properties and a substantial concomitant drop in INF?. Concurrently, Daclizumab treatment triggered a significant reduction in both the uveal histopathological grading and protein concentration in aqueous humors, but not in cellular infiltration. PMID:24595020

  6. Cow allergen (Bos d2) and endotoxin concentrations are higher in the settled dust of homes proximate to industrial-scale dairy operations.

    PubMed

    Williams, D' Ann L; McCormack, Meredith C; Matsui, Elizabeth C; Diette, Gregory B; McKenzie, Shawn E; Geyh, Alison S; Breysse, Patrick N

    2016-01-01

    Airborne contaminants produced by industrial agricultural facilities contain chemical and biological compounds that can impact the health of residents living in close proximity. Settled dust can be a reservoir for these contaminants and can influence long-term exposures. In this study, we sampled the indoor- and outdoor-settled dust from 40 homes that varied in proximity to industrial-scale dairies (ISD; industrial-scale dairy, a term used in this paper to describe a large dairy farm and adjacent waste sprayfields, concentrated animal feeding operation or animal feeding operation, that uses industrial processes) in the Yakima Valley, Washington. We analyzed settled dust samples for cow allergen (Bos d2, a cow allergen associated with dander, hair, sweat and urine, it is a member of the lipocalin family of allergens associated with mammals), mouse allergen (Mus m1; major mouse allergen, a mouse urinary allergen, in the lipocalin family), dust mite allergens (Der p1 (Dermatophagoides pteronissinus 1) and Der f1 (Dermatophagoides farinae 1)), and endotoxin (a component of the cell walls of gram negative bacteria, lipopolysaccharide, which can be found in air and dust and can produce a strong inflammatory response). A concentration gradient was observed for Bos d2 and endotoxin measured in outdoor-settled dust samples based on proximity to ISD. Indoor-settled dust concentrations of Bos d2 and endotoxin were also highest in proximal homes. While the associated health effects of exposure to cow allergen in settled dust is unknown, endotoxin at concentrations observed in these proximal homes (100?EU/mg) has been associated with increased negative respiratory health effects. These findings document that biological contaminants emitted from ISDs are elevated in indoor- and outdoor-settled dust samples at homes close to these facilities and extend to as much as three miles (4.8?km) away. PMID:25138294

  7. Endotoxin removal from water using microporous polyethylene chopped fibres as a new adsorbent.

    PubMed Central

    Sawada, Y.; Fujii, R.; Igami, I.; Kawai, A.; Kamiki, T.; Niwa, M.

    1986-01-01

    A new adsorbent, microporous polyethylene chopped fibre, was produced from a high density polyethylene. This can adsorb lipopolysaccharides (LPS) linearly up to 2 h, and showed the highest capacity to adsorb LPS when compared with two other polyethylene-based adsorbents and a polystyrene-based adsorbent. More than twice as much orange II and 4-nitroquinoline N oxide were adsorbed in the new adsorbent as was LPS. The adsorption isotherm of the new adsorbent for LPS was of Ln type, the correlation between adsorption and concentration of solute was proportional; whereas orange II and 4-nitroquinoline N oxide were of L type (greater adsorption than Ln type); tetrachloroethylene adsorption was of S type, less than Ln type. Adsorption of LPS to the new adsorbent increased when temperature rose, whereas adsorption of orange II and 4-nitroquinoline N oxide decreased. These data suggest that the binding of LPS to the new adsorbent is a hydrophobic interaction, whereas the binding of both orange II and 4-nitroquinoline N oxide is not. The new adsorbent has a greater potential for the removal of endotoxin from tap water than other commercially available adsorbents such as charcoal and Amberlite XAD-2. Images Fig. 1 PMID:3734438

  8. Maternal endotoxin exposure results in abnormal neuronal architecture in the newborn rabbit

    PubMed Central

    Balakrishnan, Bindu; Dai, Hui; Janisse, James; Romero, Roberto; Kannan, Sujatha

    2014-01-01

    Maternal intrauterine inflammation/infection is a potential risk factor for the development of neurologic disorders such as cerebral palsy in preterm and term infants. Cerebral palsy is associated with white matter and grey matter injury. In the current study, we used a rabbit model of cerebral palsy in which pregnant rabbits are administered intrauterine injections of the endotoxin lipopolysaccharide. We then investigated the extent of neuronal damage in the newborn kit brain. We observed an overall decrease in number of MAP2-stained neurons and an increase in Fluoro-Jade C-stained cells in the anterior thalamus of 1-day-old rabbit brain. We also observed an overall decrease in the number of branching points and spine density in the retrosplenial cortex, a major output region of the anterior thalamus that is involved in cognition and memory. The loss of spines and dendritic atrophy in the retrosplenial cortex may be caused by loss of presynaptic input from the thalamus. Our study indicates that the cognitive impairments seen in patients with cerebral palsy may be related to degeneration of neurons and abnormal arborization of the thalamic and cortical neurons. PMID:23988854

  9. Endotoxin tolerance alleviates experimental acute liver failure via inhibition of high mobility group box 1

    PubMed Central

    Yang, Nai-Bin; Ni, Shun-Lan; Li, Shan-Shan; Zhang, Sai-Nan; Hu, Dan-Ping; Lu, Ming-Qin

    2015-01-01

    High mobility group box 1 (HMGB1) has been widely reported to mediate damage caused by inflammatory responses. The aim of our study is to investigate the role of HMGB1 in endotoxin tolerance (ET) alleviating inflammation of acute liver failure (ALF) rats and its possible signaling mechanism. To mimic ET, male Sprague-Dawley rats were pretreated with low dose of lipopolysaccharide (LPS) (0.1 mg/kg once a day intraperitoneally for consecutive five days) before subsequent ALF induction. ALF was induced by intraperitoneal administration of D-GalN/LPS. ET induced by LPS pretreatment significantly improved the survival rate of ALF rats. Moreover, after ALF induction, ET+ALF rats exhibited lower serum enzyme (ALT, AST and TBiL) levels, lower production of inflammatory cytokines (IL-6, TNF-a and HMGB1) and more minor liver histopathological damage than ALF rats. ET+ALF rats showed enhanced expression levels of HMGB1, decreased levels of STAT1 and p-STAT1, augmented expression of SOCS1 in liver tissues than ALF rats. These results indicated that ET induced by low-dose LPS pretreatment may alleviate inflammation and liver injury in experimental acute liver failure rats mainly through inhibition of hepatic HMGB1 translocation and release. PMID:26464648

  10. Endothelin B receptors preserve renal blood flow in a normotensive model of endotoxin-induced acute kidney dysfunction.

    PubMed

    Nitescu, Nicoletta; Grimberg, Elisabeth; Ricksten, Sven-Erik; Herlitz, Hans; Guron, Gregor

    2008-03-01

    The aim was to investigate the role of endothelin 1 receptor subtypes in the early renal response to lipopolysaccharide (LPS) during normotensive endotoxemia with acute kidney dysfunction. Endotoxemia was induced in thiobutabarbital-anesthetized rats (n = 9 per group) by infusion of LPS (dosage, 1 mg/kg per hour i.v.). The study groups (1) sham-saline, (2) LPS-saline, (3) LPS-BQ123, (4) LPS-BQ788 and (5) LPS-BQ123 + BQ788 received isotonic saline, the ETA receptor antagonist BQ-123 (dosage, 30 nmol/kg per minute i.v.), and/or the ETB receptor antagonist BQ-788 (dosage, 30 nmol/kg per minute i.v.) before and during 2 h of LPS infusion. Renal clearance measurements, renal blood flow (RBF), and cortical and outer medullary perfusion (laser-Doppler flowmetry) and oxygen tension (Clark-type microelectrodes) were analyzed throughout. Before LPS administration, there were no significant differences between groups in glomerular filtration rate (GFR), RBF, or in cortical (CLDF) and outer medullary perfusion. However, mean arterial pressure (MAP) was elevated in LPS-BQ788 group compared with LPS-BQ123 + BQ788 group (P < 0.05). In saline-treated rats, endotoxin induced an approximate 35% reduction in GFR (P < 0.05), without significant effects on MAP, RBF, or on CLDF and cortical PO2. In addition, LPS increased outer medullary perfusion and PO2 (P < 0.05). The fractional urinary excretion rates of sodium, potassium, and water were not significantly different in LPS-saline group compared with sham-saline group. Neither selective nor combined ETA and ETB receptor blockade improved GFR. In BQ-788-infused rats, endotoxin produced marked reductions in RBF (-18% +/- 4% [P < 0.05]) and CLDF (-18% +/- 2% [P < 0.05]). Similarly, endotoxin decreased RBF (-14% +/- 3% [P < 0.05]) and CLDF (-10% +/- 2% [P < 0.05]) in LPS-BQ123 + BQ788 group. Endotoxin reduced MAP (-22% +/- 4% [P < 0.05]) in BQ-123-treated rats but did not significantly influence MAP in other groups. We conclude that in early normotensive endotoxemia, ETB receptors exert a renal vasodilator influence and contribute to maintain normal RBF. PMID:17693943

  11. Ragweed pollen extract intensifies lipopolysaccharide-induced priming of NLRP3 inflammasome in human macrophages

    PubMed Central

    Varga, Aliz; Budai, Marietta M; Milesz, Sándor; Bácsi, Attila; T?zsér, József; Benk?, Szilvia

    2013-01-01

    Ragweed pollen extract (RWE) possesses intrinsic NADPH oxidase activity that induces oxidative stress by initiating the production of intracellular reactive oxygen species (ROS). The ROS are important contributors to the manifestation of allergic inflammation; furthermore, concomitant exposure to an allergen and an endotoxin trigger a stronger inflammatory response. One of the main pro-inflammatory cytokines produced in inflammatory responses is interleukin-1? (IL-1?), and its production is associated with caspase-1-containing inflammasome complexes. Intracellular ROS have been implicated in NLRP3 inflammasome-mediated IL-1? production, therefore, we aimed to study whether RWE influences the function of NLRP3 inflammasome. Here we describe that, in the presence of NADPH, RWE significantly elevates lipopolysaccharide-induced IL-1? production of THP-1 cells as well as human primary macrophages and dendritic cells. We also demonstrate that increased IL-1? production is mediated through NLRP3 inflammasome in THP-1 macrophages. We provide evidence that RWE elevates cytosolic ROS level in these cells, and ROS inhibitors abolish IL-1? production. Furthermore, we show that RWE enhances lipopolysaccharide-induced gene transcription/expression of pro-IL-1? and key components of the inflammasome via a ROS-dependent mechanism. PMID:23278511

  12. Deciphering the dual effect of lipopolysaccharides from plant pathogenic Pectobacterium.

    PubMed

    Mohamed, Kettani-Halabi; Daniel, Tran; Aurélien, Dauphin; El-Maarouf-Bouteau, Hayat; Rafik, Errakhi; Arbelet-Bonnin, Delphine; Biligui, Bernadette; Florence, Val; Mustapha, Ennaji Moulay; François, Bouteau

    2015-01-01

    Lipopolysaccharides (LPS) are a component of the outer cell surface of almost all Gram-negative bacteria and play an essential role for bacterial growth and survival. Lipopolysaccharides represent typical microbe-associated molecular pattern (MAMP) molecules and have been reported to induce defense-related responses, including the expression of defense genes and the suppression of the hypersensitive response in plants. However, depending on their origin and the challenged plant, LPS were shown to have complex and different roles. In this study we showed that LPS from plant pathogens Pectobacterium atrosepticum and Pectobacterium carotovorum subsp. carotovorum induce common and different responses in A. thaliana cells when compared to those induced by LPS from non-phytopathogens Escherichia coli and Pseudomonas aeruginosa. Among common responses to both types of LPS are the transcription of defense genes and their ability to limit of cell death induced by Pectobacterium carotovorum subsp carotovorum. However, the differential kinetics and amplitude in reactive oxygen species (ROS) generation seemed to regulate defense gene transcription and be determinant to induce programmed cell death in response to LPS from the plant pathogenic Pectobacterium. These data suggest that different signaling pathways could be activated by LPS in A. thaliana cells. PMID:25760034

  13. Lipopolysaccharide mutants of Rhizobium meliloti are not defective in symbiosis

    SciTech Connect

    Clover, R.H.; Kieber, J.; Signer, E.R. )

    1989-07-01

    Mutants of Rhizobium meliloti selected primarily for bacteriophage resistance fall into 13 groups. Mutants in the four best-characterized groups (class A, lpsB, lpsC, and class D), which map to the rhizobial chromosome, appear to affect lipopolysaccharide (LPS) as judged by the reactivity with monoclonal antibodies and behavior on sodium dodecyl sulfate-polyacrylamide gels of extracted LPS. Mutations in all 13 groups, in an otherwise wild-type genetic background, are Fix{sup +} on alfalfa. This suggests that LPS does not play a major role in symbiosis. Mutations in lpsB, however, are Fix{sup {minus}} in one particular genetic background, evidently because of the cumulative effect of several independent background mutations. In addition, an auxotrophic mutation evidently equivalent to Escherichia coli carAB is Fix{sup {minus}} on alfalfa.

  14. LOW-DOSE AIRBORNE ENDOTOXIN EXPOSURE ENHANCES BRONCHIAL RESPONSIVENESS TO INHALED ALLERGEN IN ATOPIC ASTHMATICS

    EPA Science Inventory

    Endotoxin exposure has been associated with both protection against development of TH2-immune responses during childhood and exacerbation of asthma in persons who already have allergic airway inflammation.1 Occupational and experimental inhalation exposures to endotoxin have been...

  15. ALLERGEN PROVOCATION AUGMENTS ENDOTOXIN-INDUCED NASAL INFLAMMATION IN ATOPIC ASTHMATICS

    EPA Science Inventory

    Background: Recent epidemiologic and in vivo studies have suggested that inhaled endotoxin plays an important role in asthma pathogenesis.
    Objective: The present study examines the effect of nasal allergen provocation on subsequent endotoxin challenges in subjects with atopi...

  16. Lumican overexpression exacerbates lipopolysaccharide-induced renal injury in mice

    PubMed Central

    LU, XIAO-MEI; MA, LING; JIN, YU-NAN; YU, YAN-QIU

    2015-01-01

    The present study aimed to investigate the role of lumican in mice with endotoxin-induced acute renal failure (ARF). Lumican transgenic mice and wild-type mice were injected with lipopolysaccharide (LPS; 10 mg/kg) to establish a model of ARF. The mice were sacrificed at 24 h and the blood and renal tissue samples were collected. The value of serum creatinine (SCr) and blood urea nitrogen (BUN) were measured to determine renal function. An ELISA was used to determined the concentrations of renal cytokines, including tumor necrosis factor (TNF)?, interleukin (IL)-6, IL-4 and IL-10. The protein expression levels of Toll-like receptor (TLR4) and nuclear factor (NF)?B in renal tissues were assessed using western blot analysis. Terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling was performed to monitor apoptosis of renal tissue. Light microscopy and electron microscopy were used to observe structural changes in the renal tissues. Following the administration of LPS, the SCr and BUN values of mice in the lumican transgenic group were higher compared with those in the control group. The expression levels of renal TLR4, NF?B, TNF?, IL-6, IL-4 and IL-10 were upregulated in the lumican transgenic mice compared with those in the wild-type control group. Apoptosis was detected predominantly on the renal tubule. There was a significant difference in the optical density of apoptotic bodies between the control mice and the lumican transgenic mice. Light and electron microscopy demonstrated more severe renal tissue injury in the lumican transgenic mice compared with that in the control mice. In conclusion, LPS may cause excessive apoptosis in the renal tubular cells via the TLR4 signal transduction pathway, a decrease in the number of renal tubular cells and ARF. Lumican may be important in mice with LPS-induced ARF. PMID:26081832

  17. Prevention of cardiac damage induced by formyl-leurosine, a potent cytostatic agent, by radio-detoxified endotoxin (Tolerin) in dogs

    SciTech Connect

    Bertok, L.; Juhasz-Nagy, A.; Sotonyi, P.

    1984-08-01

    Radio-detoxified endotoxin (Tolerin), produced by /sup 60/Co-gamma irradiation of Escherichia coli 089 endotoxin, can protect dogs against the acute cardiotoxic side-effects of formyl-leurosine, a semi-synthetic Vinca derivative with promising antineoplastic potency. Formyl-leurosine induces a rapid decrease in arterial blood pressure and diminishes the contractile force of the myocardium in the anaesthetized dog. These responses indicate a direct pharmacologic relaxant effect of the drug on the heart and vasculature smooth muscle. The early cardiovascular depression is of short duration and is unaffected by Tolerin. Tolerin can prevent, however, the secondary, more dangerous phase of circulatory depression that is associated with the severe cardiotoxic manifestations of the drug, as demonstrated by hemodynamic and morphologic (light and electronmicroscopic) patterns.

  18. Airborne endotoxin concentrations at a large open-lot dairy in southern Idaho

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Endotoxins are derived from Gram-negative bacteria and are a potential respiratory health risk for animals and humans. To determine the potential for endotoxin transport from a large open lot dairy, airborne endotoxin concentrations were determined at an upwind location (background) and five downwi...

  19. 40 CFR 180.1107 - Delta endotoxin of Bacillus thuringiensis variety kurstaki encapsulated into killed Pseudomonas...

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 23 2010-07-01 2010-07-01 false Delta endotoxin of Bacillus... From Tolerances § 180.1107 Delta endotoxin of Bacillus thuringiensis variety kurstaki encapsulated into killed Pseudomonas fluorescens; exemption from the requirement of a tolerance. The delta endotoxin...

  20. 40 CFR 180.1107 - Delta endotoxin of Bacillus thuringiensis variety kurstaki encapsulated into killed Pseudomonas...

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 25 2012-07-01 2012-07-01 false Delta endotoxin of Bacillus... From Tolerances § 180.1107 Delta endotoxin of Bacillus thuringiensis variety kurstaki encapsulated into killed Pseudomonas fluorescens; exemption from the requirement of a tolerance. The delta endotoxin...

  1. 40 CFR 180.1107 - Delta endotoxin of Bacillus thuringiensis variety kurstaki encapsulated into killed Pseudomonas...

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 24 2014-07-01 2014-07-01 false Delta endotoxin of Bacillus... From Tolerances § 180.1107 Delta endotoxin of Bacillus thuringiensis variety kurstaki encapsulated into killed Pseudomonas fluorescens; exemption from the requirement of a tolerance. The delta endotoxin...

  2. 40 CFR 180.1107 - Delta endotoxin of Bacillus thuringiensis variety kurstaki encapsulated into killed Pseudomonas...

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 24 2011-07-01 2011-07-01 false Delta endotoxin of Bacillus... From Tolerances § 180.1107 Delta endotoxin of Bacillus thuringiensis variety kurstaki encapsulated into killed Pseudomonas fluorescens; exemption from the requirement of a tolerance. The delta endotoxin...

  3. 40 CFR 180.1107 - Delta endotoxin of Bacillus thuringiensis variety kurstaki encapsulated into killed Pseudomonas...

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 25 2013-07-01 2013-07-01 false Delta endotoxin of Bacillus... From Tolerances § 180.1107 Delta endotoxin of Bacillus thuringiensis variety kurstaki encapsulated into killed Pseudomonas fluorescens; exemption from the requirement of a tolerance. The delta endotoxin...

  4. Critical residues involved in Toll-like receptor 4 activation by cationic lipid nanocarriers are not located at the lipopolysaccharide-binding interface

    E-print Network

    Lonez, Caroline; Irvine, Kate L.; Pizzuto, Malvina; Schmidt, Boris I.; Gay, Nick J.; Ruysschaert, Jean-Marie; Gangloff, Monique; Bryant, Clare E.

    2015-05-09

    DiC14-amidine is a cationic lipid that was originally designed as a lipid nanocarrier for nucleic acid transport, and turned out to be a Toll-like receptor 4 (TLR4) agonist as well. We found that while E.coli lipopolysaccharide (LPS) is a TLR4...

  5. Innate immune activation in neonatal tracheal aspirates suggests endotoxin-driven inflammation

    PubMed Central

    Nathe, Katheryn E.; Mancuso, Christy J.; Parad, Richard; Van Marter, Linda J.; Martin, Camilia R.; Stoler-Barak, Liat; Philbin, Victoria J.; Phillips, Michele F.; Palmer, Christine D.; Levy, Ofer

    2012-01-01

    Background: Tracheal aspirates (TAs) from critically ill neonates accumulate bacterial endotoxin and demonstrate mobilization of endotoxin-binding proteins, but the potential bioactivity of endotoxin in TAs is unknown. We characterized innate immune activation in TAs of mechanically ventilated neonates. Methods: Innate immune activation in TAs of mechanically ventilated neonates was characterized using a targeted 84-gene quantitative real-time (qRT) PCR array. Protein expression of cytokines was confirmed by multiplex assay. Expression and localization of the endotoxin-inducible antimicrobial protein Calgranulin C (S100A12) was assessed by flow cytometry. Endotoxin levels were measured in TA supernatants using the Limulus amoebocyte lysate assay. Results: Analyses by qRT-PCR demonstrated expression of pattern recognition receptors, Toll-like receptor-nuclear factor ?B and inflammasome pathways, cytokines/chemokines and their receptors, and anti-infective proteins in TA cells. Endotoxin positivity increased with postnatal age. As compared with endotoxin-negative TAs, endotoxin-positive TAs demonstrated significantly greater tumor necrosis factor (TNF), interleukin (IL)-6, IL-10, and serpin peptidase inhibitor, clade E, member 1 (SERPINE1) mRNA, and IL-10, TNF, and IL-1? protein. Expression of S100A12 protein was localized to TA neutrophils. Conclusion: Correlation of endotoxin with TA inflammatory responses suggests endotoxin bioactivity and the possibility that endotoxin antagonists could mitigate pulmonary inflammation and its sequelae in this vulnerable population. PMID:22580716

  6. Reduced lipopolysaccharide (LPS)-induced nitric oxide production in peritoneal macrophages and inhibited LPS-induced lethal shock in mice by a sugar cane (Saccharum officinarum L.) extract.

    PubMed

    Hikosaka, Kenji; Koyama, Yukari; Motobu, Maki; Yamada, Manabu; Nakamura, Kikuyasu; Koge, Kenji; Shimura, Kameo; Isobe, Takashi; Tsuji, Naotoshi; Kang, Chung-Boo; Hayashidani, Hideki; Wang, Pi-Chao; Matsumura, Masatoshi; Hirota, Yoshikazu

    2006-12-01

    A sugar cane extract (SCE) has been found to have an immunostimulating effect in several animals. Lipopolysaccharide (LPS) is known to induce endotoxin shock via the production of inflammatory modulators such as tumor necrosis factor (TNF)-alpha and nitric oxide (NO). We examined in the present study the effects of SCE on the TNF-alpha and NO production in LPS-stimulated mice peritoneal cells and the endotoxin shock in mice. The supplementation of SCE to peritoneal macrophages cultured with LPS resulted in a significant decrease in NO production. All the mice injected intraperitoneally with LPS and D-galactosamine (LPS+GalN) died within 24 h. However, a peritoneal injection, but no intravenous or oral administration, of SCE (500-1,000 mg/kg) at 3 to 48 h before the LPS+GalN-challenge resulted in a significantly improved survival rate. These results suggest that SCE had a protective effect on LPS-induced endotoxin shock via one of possible mechanisms involving the suppression of NO production in the mouse peritoneal cavity. PMID:17151479

  7. Interleukin-8 induces an elevation in the endotoxin activity assay (EAA) level: does the EAA truly measure the endotoxin level?

    PubMed

    Matsumoto, Naoya; Takahashi, Gaku; Kojika, Masahiro; Suzuki, Yasushi; Inoue, Yoshihiro; Inada, Katsuya; Endo, Shigeatsu

    2013-10-01

    The endotoxin activity assay (EAA) is a FDA-approved blood endotoxin assay that is reported as a useful tool for the diagnosis of gram-negative bacterial infection. However, discrepancies between the results of the EAA and those of the limulus amebocyte lysate (LAL) assay have been reported. Thus, we verified these methods. Blood was incubated with anti-endotoxin antibody, the resultant polymorphonuclear activation to produce oxidants was measured and the EAA level calculated. As a reference endotoxin assay, we used an endotoxin-specific LAL assay. Significant increases in plasma LAL assay levels were observed only in patients with sepsis caused by gram-negative bacterial infections, whereas higher EAA levels were observed in almost all the sepsis cases and the SIRS cases, especially those with acute pancreatitis. Graded amounts of LPS (1-10,000 pg/ml) were spiked into normal blood to obtain dose-response curves: a good dose-response curve, from 1 to 1,000 pg/ml, was obtained for the LAL assay. A good dose-response curve was barely obtained for the EAA; the lowest detection limit seemed to be 1,000 pg/ml. Addition of methylprednisolone decreased the EAA levels. Interleukin-8 (IL-8) induced elevation in EAA levels when IL-8 was added to volunteers' blood samples. Overall, the EAA kit could not measure clinically relevant doses of endotoxin. Because IL-8 induced an increase in EAA level, it is suggested that the EAA level reflects the primed state of polymorphonuclear leukocytes. PMID:23460381

  8. BCG priming enhances endotoxin-induced acute lung injury independent of neutrophils.

    PubMed

    Tasaka, S; Ishizaka, A; Urano, T; Sayama, K; Sakamaki, F; Nakamura, H; Terashima, T; Waki, Y; Soejima, K; Oyamada, Y

    1995-09-01

    Bacillus Calmette Guérin (BCG) is known to increase susceptibility to endotoxin in some animal species. We investigated the effect of BCG-priming and the role of neutrophils in the priming process on the pathogenesis of acute lung injury caused by intravenously administered Escherichia coli endotoxin (LPS). Guinea pigs were divided into seven groups: (1) control (n = 8), (2) BCG-alone (n = 6), (3) cyclophosphamide (CPA)-alone (n = 6), (4) CPA+LPS (n = 6), (5) LPS-alone (n = 6), (6) BCG+LPS (n = 6), and (7) BCG+CPA+LPS (n = 6). A BCG dose of 8 mg/kg was injected subcutaneously 10 d before the study. CPA was administered intraperitoneally to induce peripheral neutropenia. Animals were observed for 4 h after intravenous administration of 0.2 mg/kg of LPS. The plasma TNF level was measured 2 h after LPS challenge. Lung wet-to-dry weight ratio, [125I] albumin leakage in lung tissue, differential cell count in bronchoalveolar lavage (BAL) fluid, and histopathologic features were examined immediately after death. Although the LPS-alone group showed PMN accumulation in lung tissue, neither excess lung water nor increased albumin leakage was induced by this dose of LPS. The BCG+LPS group showed increased lung water, histopathologic edema, and increases in BAL fluid cell counts and plasma TNF in comparison with the LPS-alone group. The BCG+CPA+LPS group also showed enhanced lung injury comparable to that seen in the BCG+LPS group. In both the CPA-alone and the CPA+LPS groups, no parameter was increased as compared with those in the control group.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:7663781

  9. Endotoxin-Induced Endothelial Fibrosis Is Dependent on Expression of Transforming Growth Factors ?1 and ?2

    PubMed Central

    Echeverría, César; Montorfano, Ignacio; Tapia, Pablo; Riedel, Claudia; Cabello-Verrugio, Claudio

    2014-01-01

    During endotoxemia-induced inflammatory disease, bacterial endotoxins circulate in the bloodstream and interact with endothelial cells (ECs), inducing dysfunction of the ECs. We previously reported that endotoxins induce the conversion of ECs into activated fibroblasts. Through endotoxin-induced endothelial fibrosis, ECs change their morphology and their protein expression pattern, thereby suppressing endothelial markers and upregulating fibrotic proteins. The most commonly used fibrotic inducers are transforming growth factor ?1 (TGF-?1) and TGF-?2. However, whether TGF-?1 and TGF-?2 participate in endotoxin-induced endothelial fibrosis remains unknown. We have shown that the endotoxin-induced endothelial fibrosis process is dependent on the TGF-? receptor, ALK5, and the activation of Smad3, a protein that is activated by ALK5 activation, thus suggesting that endotoxin elicits TGF-? production to mediate endotoxin-induced endothelial fibrosis. Therefore, we investigated the dependence of endotoxin-induced endothelial fibrosis on the expression of TGF-?1 and TGF-?2. Endotoxin-treated ECs induced the expression and secretion of TGF-?1 and TGF-?2. TGF-?1 and TGF-?2 downregulation inhibited the endotoxin-induced changes in the endothelial marker VE-cadherin and in the fibrotic proteins ?-SMA and fibronectin. Thus, endotoxin induces the production of TGF-?1 and TGF-?2 as a mechanism to promote endotoxin-induced endothelial fibrosis. To the best of our knowledge, this is the first report showing that endotoxin induces endothelial fibrosis via TGF-? secretion, which represents an emerging source of vascular dysfunction. These findings contribute to understanding the molecular mechanism of endotoxin-induced endothelial fibrosis, which could be useful in the treatment of inflammatory diseases. PMID:24935972

  10. Endotoxin-induced endothelial fibrosis is dependent on expression of transforming growth factors ?1 and ?2.

    PubMed

    Echeverría, César; Montorfano, Ignacio; Tapia, Pablo; Riedel, Claudia; Cabello-Verrugio, Claudio; Simon, Felipe

    2014-09-01

    During endotoxemia-induced inflammatory disease, bacterial endotoxins circulate in the bloodstream and interact with endothelial cells (ECs), inducing dysfunction of the ECs. We previously reported that endotoxins induce the conversion of ECs into activated fibroblasts. Through endotoxin-induced endothelial fibrosis, ECs change their morphology and their protein expression pattern, thereby suppressing endothelial markers and upregulating fibrotic proteins. The most commonly used fibrotic inducers are transforming growth factor ?1 (TGF-?1) and TGF-?2. However, whether TGF-?1 and TGF-?2 participate in endotoxin-induced endothelial fibrosis remains unknown. We have shown that the endotoxin-induced endothelial fibrosis process is dependent on the TGF-? receptor, ALK5, and the activation of Smad3, a protein that is activated by ALK5 activation, thus suggesting that endotoxin elicits TGF-? production to mediate endotoxin-induced endothelial fibrosis. Therefore, we investigated the dependence of endotoxin-induced endothelial fibrosis on the expression of TGF-?1 and TGF-?2. Endotoxin-treated ECs induced the expression and secretion of TGF-?1 and TGF-?2. TGF-?1 and TGF-?2 downregulation inhibited the endotoxin-induced changes in the endothelial marker VE-cadherin and in the fibrotic proteins ?-SMA and fibronectin. Thus, endotoxin induces the production of TGF-?1 and TGF-?2 as a mechanism to promote endotoxin-induced endothelial fibrosis. To the best of our knowledge, this is the first report showing that endotoxin induces endothelial fibrosis via TGF-? secretion, which represents an emerging source of vascular dysfunction. These findings contribute to understanding the molecular mechanism of endotoxin-induced endothelial fibrosis, which could be useful in the treatment of inflammatory diseases. PMID:24935972

  11. Crystal structure of an endotoxin-neutralizing protein from the horseshoe crab, Limulus anti-LPS factor, at 1.5 A resolution.

    PubMed Central

    Hoess, A; Watson, S; Siber, G R; Liddington, R

    1993-01-01

    Lipopolysaccharide (LPS), or endotoxin, is the major mediator of septic shock, a serious complication of Gram-negative bacterial infections in humans. Molecules that bind LPS and neutralize its biological effects or enhance its clearance could have important clinical applications. Limulus anti-LPS factor (LALF) binds LPS tightly, and, in animal models, reduces mortality when administered before or after LPS challenge or bacterial infection. Here we present the high resolution structure of a recombinant LALF. It has a single domain consisting of three alpha-helices packed against a four-stranded beta-sheet. The wedge-shaped molecule has a striking charge distribution and amphipathicity that suggest how it can insert into membranes. The binding site for LPS probably involves an extended amphipathic loop, and we propose that two mammalian LPS-binding proteins will have a similar loop. The amphipathic loop structure may be used in the design of molecules with therapeutic properties against septic shock. Images PMID:8253062

  12. Lipopolysaccharide-induced production of tumour necrosis factor and interleukin-1 is differentially regulated at the receptor level: the role of CD14-dependent and CD14-independent pathways.

    PubMed Central

    Netea, M G; Kullberg, B J; van der Meer, J W

    1998-01-01

    Cytokine production induced via CD14-dependent and CD14-independent pathways was investigated in mouse peritoneal macrophages incubated with lipopolysaccharide (LPS) or lipid A. Different LPS receptors appear to be responsible for production of tumour necrosis factor-alpha (TNF-alpha) and interleukin-1 alpha (IL-1 alpha) and IL-1 beta. TNF-alpha production is essentially CD14 dependent, both in the presence or absence of plasma. In the presence of plasma, endotoxin-induced IL-1 production is mediated by CD14-dependent mechanisms, while in its absence both CD14-dependent and CD14-independent pathways are involved. Lipid A stimulates cytokine synthesis through both CD14-dependent and CD14-independent mechanisms, but its action is weaker than that of LPS, indicating that the polysaccharide moiety may be necessary for proper stimulation of mouse macrophages by endotoxin. PMID:9767415

  13. Protective phenotypes of club cells and alveolar macrophages are favored as part of endotoxin-mediated prevention of asthma.

    PubMed

    García, Luciana N; Leimgruber, Carolina; Uribe Echevarría, Elisa M; Acosta, Patricio L; Brahamian, Jorge M; Polack, Fernando P; Miró, María S; Quintar, Amado A; Sotomayor, Claudia E; Maldonado, Cristina A

    2015-07-01

    Atopic asthma is a chronic allergic disease that involves T-helper type 2 (Th2)-inflammation and airway remodeling. Bronchiolar club cells (CC) and alveolar macrophages (AM) are sentinel cells of airway barrier against inhaled injuries, where allergy induces mucous metaplasia of CC and the alternative activation of AM, which compromise host defense mechanisms and amplify Th2-inflammation. As there is evidence that high levels of environmental endotoxin modulates asthma, the goal of this study was to evaluate if the activation of local host defenses by Lipopolysaccharide (LPS) previous to allergy development can contribute to preserving CC and AM protective phenotypes. Endotoxin stimulus before allergen exposition reduced hallmarks of allergic inflammation including eosinophil influx, Interleukin-4 and airway hyperreactivity, while the T-helper type 1 related cytokines IL-12 and Interferon-? were enhanced. This response was accompanied by the preservation of the normal CC phenotype and the anti-allergic proteins Club Cell Secretory Protein (CCSP) and Surfactant-D, thereby leading to lower levels of CC metaplasia and preventing the increase of the pro-Th2 cytokine Thymic stromal lymphopoietin. In addition, classically activated alveolar macrophages expressing nitric oxide were promoted over the alternatively activated ones that expressed arginase-1. We verified that LPS induced a long-term overexpression of CCSP and the innate immune markers Toll-like receptor 4, and Tumor Necrosis Factor-?, changes that were preserved in spite of the allergen challenge. These results demonstrate that LPS pre-exposition modifies the local bronchioalveolar microenvironment by inducing natural anti-allergic mechanisms while reducing local factors that drive Th2 type responses, thus modulating allergic inflammation. PMID:25504013

  14. Identification of tumor necrosis factor as a transcriptional regulator of the phosphoenolpyruvate carboxykinase gene following endotoxin treatment of mice.

    PubMed Central

    Hill, M R; McCallum, R E

    1992-01-01

    The decreased synthesis of hepatic phosphoenolpyruvate carboxykinase (PEPCK), the rate-limiting enzyme of gluconeogenesis, that occurs during endotoxemia was shown previously in rats to occur at the transcriptional level. In the current study, the exogenous administration of human recombinant tumor necrosis factor (TNF), a proximal mediator of endotoxic shock, reduced the PEPCK transcription rate, mRNAPEPCK levels, and PEPCK enzyme activity in a time- and dose-dependent manner in CD-1 mice. Comparable amounts of circulating TNF were measured in mice 2 h after injection of human recombinant TNF (10(5) U) or a 50% lethal dose of Escherichia coli endotoxin (20 mg/kg). Direct action of TNF to decrease the PEPCK transcription rate was confirmed in vitro with H-4-II-E Reuber hepatoma cells, in which a dose-dependent inhibition of PEPCK transcription was observed with 1 to 100 U of TNF per ml. A role for TNF-elicited changes in PEPCK gene expression during endotoxemia was confirmed by the protective effect of rabbit polyclonal antibodies to recombinant murine TNF. C57BL/6 mice passively immunized with anti-TNF 4 h prior to endotoxin challenge exhibited normal PEPCK enzyme activity. Neutralization of circulating TNF with anti-TNF failed, however, to prevent the hypoglycemia commonly observed during endotoxemia, suggesting the participation of other mediators. Anti-TNF treatment reduced circulating interleukins 1 and 6 at 3 and 6 h after endotoxin treatment, respectively. These results suggest that during endotoxemia, the development of hypoglycemia is multifaceted and that several cytokines are most likely involved. The findings from the Reuber hepatoma cell model afford an opportunity in future work to map putative cytokine response elements in the PEPCK promoter responsible for perturbed hormonal regulation of the gene during endotoxemia. PMID:1398916

  15. Streptomycetes in house dust: associations with housing characteristics and endotoxin

    EPA Science Inventory

    In addition to mold, indoor bioaerosols also contain bacterial components that may have implications for human health. Endotoxin is a cell wall component in Gram-negative bacteria present at varying levels indoors that has been found to have respiratory health implications. Stre...

  16. Optimizing the extraction, storage, and analysis of airborne endotoxins

    Technology Transfer Automated Retrieval System (TEKTRAN)

    While the Limulus amebocyte lysate (LAL) assay is part of most procedures to assess airborne endotoxin exposure, there is no universally agreed upon standard procedure. The purpose of this study was to fill in additional knowledge gaps with respect to the extraction, storage, and analysis of endotox...

  17. [Endotoxin Is a Companent in Pathogenesis of Chronic Viral Diseases].

    PubMed

    Anikhovskaya, I; Kubatiev, A; Khasanova, G; Yakovlev, M

    2015-01-01

    The level of endotoxin and indicators of activity of antiendotoxin immunity (antibody concentration to glycolipid Re-chemotype and general antigen of enterobacteria) were estimated in serum of 174 patients with persistent viral infections (viruses: herpes simplex, hepatitis C, human immunodeficiency). The presence of markers of systemic inflammatory response syndrome (interleukin IL-1?) and acquired immunodeficiency (CD4+) in HIV-infected patients were also determined. Persistent viral infections are accompanied by endotoxin aggression intestinal origin (caused by them), which is able to induce the development of systemic inflammatory response syndrome. In HIV-infected patients with this syndrome is cyclical, when the phase of hyperactivity replaced immunodeficiency. Schematically, this process can be represented as the following sequence of events: HIV-mediated damage to the intestinal barrier--the development of endotoxin aggression--induction ofsystemic inflammatory response syndrome--the depletion of the immune system, which is transient and is related to the duration of activity of the virus replication cycle, i.e., with damage to enterocytes. Using antiendotoxin component (means of reducing levels of endotoxin in the blood) in the scheme of treatment of persistent viral infections can serve as an element of a successful prevention of complications. PMID:26237956

  18. [Endotoxins in gastroenterology--a medico-historical sketch].

    PubMed

    Knoke, M

    1984-01-01

    First descriptions of effects of intestinal bacterial endotoxins date from the middle of the 19th century (P. L. Panum et al.). The antitoxic function of the liver has been investigated by I. P. Pawlow in 1893. At the turn of the last century the theory of "auto-intoxication" (C. Bouchard, I. I. Metschnikoff et al.) was well known, but there were also first systematic studies of the facultatively pathogenic intestinal bacteria (T. Escherich, H. Tissier, J. Strasburger). In the twenties of our century V. van der Reis and L. Bogendoerfer worked out important fundamentals of human gastrointestinal microecology. Endotoxins as component of cellular wall of gram-negative bacteria are found by A. Boivin et al., J. W. Walker et al. First applicable proof for the detection of endotoxins was the pyrogen test with rabbits. The Limulus amoebocyte lysate test (J. Levin and F. B. Bang) has been employed as a more simple, rapid and sensitive method and was introduced in gastroenterology in a larger extent. Connections between endotoxinaemia and liver diseases, effects of endotoxins on gastrointestinal mucosa and on the course of shock are subjects of actual investigations. PMID:6389082

  19. Early-onset inflammatory responses in vivo to adenoviral vectors in the presence or absence of lipopolysaccharide-induced inflammation.

    PubMed

    Thorne, P S; McCray, P B; Howe, T S; O'Neill, M A

    1999-06-01

    Adenoviral vectors (Ad) have potential for use in pulmonary gene transfer for treating cystic fibrosis (CF). However, Ad may induce inflammation even in the absence of gene expression. Endotoxin from gram-negative bacteria in the airways of CF patients may also induce inflammation, and may further inhibit vector delivery and gene transfer. We used a mouse model to study the time course of Ad-induced lung inflammation and to assess additivity with lipopolysaccharide (LPS)-induced inflammatory responses. C3H/HeJ endotoxin-resistant (RES) mice hyporesponsive to inflammatory stimuli and normoresponsive C3HeB/FeJ endotoxin-sensitive (SEN) mice were studied to characterize inflammatory responses that follow intratracheal instillation of inactivated Ad, with or without simultaneous inhalation exposure to LPS. Instillation of 10(10) Ad particles dramatically increased bronchoalveolar lavage fluid (BALF) concentrations of tumor necrosis factor (TNF)-alpha and interleukin (IL)-6 at 3 to 6 h and induced profound neutrophilia, maximal at 12 to 24 h. SEN mice had tenfold greater responses than did RES mice at 6, 12, and 24 h. Mice exposed to Ad alone, LPS alone, or Ad + LPS had significant inflammation at the 3-h time point as demonstrated by BALF neutrophils, TNF-alpha, and IL-6. With all three treatments, SEN mice had a five- to 300-fold greater response than did RES mice. Importantly, Ad + LPS yielded no greater inflammatory response than LPS without Ad. These data demonstrate that replication-deficient Ad induce early inflammation and LPS-induced inflammation is not augmented by concurrent treatment with Ad. PMID:10340934

  20. Endotoxin-induced skeletal muscle wasting is prevented by angiotensin-(1-7) through a p38 MAPK-dependent mechanism.

    PubMed

    Morales, María Gabriela; Olguín, Hugo; Di Capua, Gabriella; Brandan, Enrique; Simon, Felipe; Cabello-Verrugio, Claudio

    2015-09-01

    Skeletal muscle atrophy induced during sepsis syndrome produced by endotoxin in the form of LPS (lipopolysaccharide), is a pathological condition characterized by the loss of strength and muscle mass, an increase in MHC (myosin heavy chain) degradation, and an increase in the expression of atrogin-1 and MuRF-1 (muscle-specific RING-finger protein 1), two ubiquitin E3 ligases belonging to the ubiquitin-proteasome system. Ang-(1-7) [Angiotensin-(1-7)], through its Mas receptor, has beneficial effects in skeletal muscle. We evaluated in vivo the role of Ang-(1-7) and Mas receptor on the muscle wasting induced by LPS injection into C57BL/10J mice. In vitro studies were performed in murine C2C12 myotubes and isolated myofibres from EDL (extensor digitorum longus) muscle. In addition, the participation of p38 MAPK (mitogen-activated protein kinase) in the Ang-(1-7) effect on the LPS-induced muscle atrophy was evaluated. Our results show that Ang-(1-7) prevents the decrease in the diameter of myofibres and myotubes, the decrease in muscle strength, the diminution in MHC levels and the induction of atrogin-1 and MuRF-1 expression, all of which are induced by LPS. These effects were reversed by using A779, a Mas antagonist. Ang-(1-7) exerts these anti-atrophic effects at least in part by inhibiting the LPS-dependent activation of p38 MAPK both in vitro and in vivo. We have demonstrated for the first time that Ang-(1-7) counteracts the skeletal muscle atrophy induced by endotoxin through a mechanism dependent on the Mas receptor that involves a decrease in p38 MAPK phosphorylation. The present study indicates that Ang-(1-7) is a novel molecule with a potential therapeutic use to improve muscle wasting during endotoxin-induced sepsis syndrome. PMID:25989282

  1. Reduction of endotoxin attenuates liver fibrosis through suppression of hepatic stellate cell activation and remission of intestinal permeability in a rat non-alcoholic steatohepatitis model.

    PubMed

    Douhara, Akitoshi; Moriya, Kei; Yoshiji, Hitoshi; Noguchi, Ryuichi; Namisaki, Tadashi; Kitade, Mitsuteru; Kaji, Kosuke; Aihara, Yosuke; Nishimura, Norihisa; Takeda, Kosuke; Okura, Yasushi; Kawaratani, Hideto; Fukui, Hiroshi

    2015-03-01

    Previous clinical studies have demonstrated that endotoxin/toll?like receptor 4 (TLR4) signaling is critical in the inflammatory pathways associated with non?alcoholic steatohepatitis (NASH). In human and animal studies, NASH was associated with portal lipopolysaccharide (LPS) and the plasma LPS level was hypothesized to be associated with small intestinal bacterial overgrowth, change in composition of the microbiota and increased intestinal permeability. The aim of the present study was to investigate the roles of endogenous endotoxin and TLR4 in the pathogenesis of NASH. The effects of antibiotics were assessed in vivo using a choline deficiency amino acid (CDAA)?induced experimental liver fibrosis model. Antibiotics, including polymyxins and neomycins, were orally administered in drinking water. Antibiotics attenuated hepatic stellate cell (HSC) activation and liver fibrosis via TGF?? and collagen in an experimental hepatic fibrosis model. The mechanism by which antibiotics attenuated LPS?TLR4 signaling and liver fibrosis was assessed. Notably, TLR4 mRNA level in the liver was elevated in the CDAA group and the CDAA?induced increase was significantly reduced by antibiotics. However, no significant differences were observed in the intestine among all groups. Elevated mRNA levels of LPS binding protein, which was correlated with serum endotoxin levels, were recognized in the CDAA group and the CDAA?induced increase was significantly reduced by antibiotics. The intestinal permeability of the CDAA group was increased compared with the choline?supplemented amino acid group. The tight junction protein (TJP) in the intestine, determined by immunohistochemical analysis was inversely associated with intestinal permeability. Antibiotics improved the intestinal permeability and enhanced TJP expression. Inhibition of LPS?TLR4 signaling with antibiotics attenuated liver fibrosis development associated with NASH via the inhibition of HSC activation. These results indicated that reduction of LPS and restoration of intestinal TJP may be a novel therapeutic strategy for treatment of liver fibrosis development in NASH. PMID:25421042

  2. Reduction of endotoxin attenuates liver fibrosis through suppression of hepatic stellate cell activation and remission of intestinal permeability in a rat non-alcoholic steatohepatitis model

    PubMed Central

    DOUHARA, AKITOSHI; MORIYA, KEI; YOSHIJI, HITOSHI; NOGUCHI, RYUICHI; NAMISAKI, TADASHI; KITADE, MITSUTERU; KAJI, KOSUKE; AIHARA, YOSUKE; NISHIMURA, NORIHISA; TAKEDA, KOSUKE; OKURA, YASUSHI; KAWARATANI, HIDETO; FUKUI, HIROSHI

    2015-01-01

    Previous clinical studies have demonstrated that endotoxin/toll-like receptor 4 (TLR4) signaling is critical in the inflammatory pathways associated with non-alcoholic steatohepatitis (NASH). In human and animal studies, NASH was associated with portal lipopolysaccharide (LPS) and the plasma LPS level was hypothesized to be associated with small intestinal bacterial overgrowth, change in composition of the microbiota and increased intestinal permeability. The aim of the present study was to investigate the roles of endogenous endotoxin and TLR4 in the pathogenesis of NASH. The effects of antibiotics were assessed in vivo using a choline deficiency amino acid (CDAA)-induced experimental liver fibrosis model. Antibiotics, including polymyxins and neomycins, were orally administered in drinking water. Antibiotics attenuated hepatic stellate cell (HSC) activation and liver fibrosis via TGF-? and collagen in an experimental hepatic fibrosis model. The mechanism by which antibiotics attenuated LPS-TLR4 signaling and liver fibrosis was assessed. Notably, TLR4 mRNA level in the liver was elevated in the CDAA group and the CDAA-induced increase was significantly reduced by antibiotics. However, no significant differences were observed in the intestine among all groups. Elevated mRNA levels of LPS binding protein, which was correlated with serum endotoxin levels, were recognized in the CDAA group and the CDAA-induced increase was significantly reduced by antibiotics. The intestinal permeability of the CDAA group was increased compared with the choline-supplemented amino acid group. The tight junction protein (TJP) in the intestine, determined by immunohistochemical analysis was inversely associated with intestinal permeability. Antibiotics improved the intestinal permeability and enhanced TJP expression. Inhibition of LPS-TLR4 signaling with antibiotics attenuated liver fibrosis development associated with NASH via the inhibition of HSC activation. These results indicated that reduction of LPS and restoration of intestinal TJP may be a novel therapeutic strategy for treatment of liver fibrosis development in NASH. PMID:25421042

  3. Des-Arg9-bradykinin causes kinin B1 receptor mediated endothelium-independent contractions in endotoxin-treated porcine coronary arteries.

    PubMed

    More, Amar S; Kim, Hye Min; Khang, Gilson; Hildebrandt, Tobias; Bernlöhr, Christian; Doods, Henri; Vanhoutte, Paul M; Wu, Dongmei

    2014-12-01

    This study examined responses of isolated pig coronary arteries after kinin B1 receptor induction by endotoxin. Des-Arg9-bradykinin (DBK) induced concentration-dependent, endothelium-independent contractions in lipopolysaccharide (LPS)-treated but not untreated arterial rings. The B1-receptor antagonist SSR240612, but not the B2-receptor antagonist HOE140, prevented the endothelium-independent contractions to DBK. The DBK-induced contractions were blocked by indomethacin (nonselective cyclooxygenase [COX] inhibitor), celecoxib (selective COX-2 inhibitor), and terbogrel (thromboxane-prostanoid [TP] receptor antagonist) but not valeryl salicylate (selective COX-1 inhibitor), AH6809 (an E prostanoid [EP] and PGD2 receptor [DP1] receptor antagonist), AL 8810 (a selective PGF2? [FP] receptor antagonist), or RO1138452 (a selective I prostanoid [IP] receptor antagonist). They were attenuated by N-(p-amylcinnamoyl) anthranilic acid (ACA), and by DETCA plus tiron but not by l-NAME. Quantitative RT-PCR revealed excessive up-regulations of mRNA expressions of B1 receptors, COX-2, and thromboxane A synthase 1 (TBXAS1) following LPS incubation, but not of B2 receptors or COX-1. The present data demonstrate that B1 receptors are coupled to COX-2 in causing endothelium-independent contractions in endotoxin-treated pig coronary arteries. Accordingly, kinin B1 receptor induction during inflammation may have a pathological significance in the vasculature, particular in coronary arteries with dysfunctional endothelial cells. PMID:25258294

  4. Fusion Peptides CPU1 and CPU2 Inhibit Matrix Metalloproteinases and Protect Mice from Endotoxin Shock Within a Strict Time Window.

    PubMed

    Qiu, Zheng; Zhang, Fengguo; Gong, Chengxin; Xu, Hanmei; Hu, Jialiang

    2015-12-01

    Endotoxin shock induction in mice is a commonly used animal model to evaluate the protective effect of biologically active reagents. After an lipopolysaccharides (LPS) stimulus, matrix metalloproteinase-8 (MMP-8) and matrix metalloproteinase-9 (MMP-9) are rapidly degranulated and released by neutrophils, aside other enzymes and effector molecules. MMPs cleave extracellular matrix components and cytokines, and such processes contribute to shock syndrome development. CPU1 and CPU2 are two peptide MMP inhibitors with different in vitro IC50 values to several key enzymes, including MMP-8 and MMP-9. In vivo work confirmed that CPU1 and CPU2 protected mice from endotoxin shock after intravenous and intraperitoneal injections. Furthermore, their minimal effective dose after an intravenous injection and the maximum time interval between intraperitoneal peptide injection (150 mg/kg) and intravenous LPS injection were determined. With the use of an indirect competitive ELISA, plasma CPU1 and CPU2 concentrations in different experimental settings were measured. In addition, the acuteness of MMP-9 release in the mouse circulation after an intravenous LPS injection was confirmed with the zymography technique. Our findings reinforce previous work with other inhibitors about a strict time window within which effective MMP inhibition is needed to obtain significant survival rate improvements and also show that, with strict pharmacokinetic monitoring, potent protease inhibitors may in the future become life-savers in shock conditions. PMID:26111477

  5. Determination of endotoxin in injectable antibiotic preparations by the chromogenic assay method using a Limulus reagent (Tachypleus hemocyte lysate) and a chromogenic substrate.

    PubMed Central

    Yano, S; Hotta, Y; Takahashi, S

    1986-01-01

    The effects of 50 antibiotics on the detection and determination of bacterial endotoxins by the chromogenic method using a Limulus reagent (Tachypleus hemocyte lysate) and a chromogenic substrate of p-nitroaniline derivatives were tested, and the antibiotic concentration for 50% inhibition of the chromogenic reaction in the presence of 0.5 ng of endotoxin (Escherichia coli 0111:B4) per ml was estimated. All the antibiotic preparations were depyrogenized by ultrafiltration treatment before they were subjected to the test. The reaction was conducted in the presence of a high concentration (0.5 M) of Tris buffer to constantly maintain the pH of the reaction mixture, and liberated p-nitroaniline was determined by high-pressure liquid chromatography. Several aminoglycosides (amikacin, bekanamycin, kanamycin, and streptomycin sulfate), bleomycin hydrochloride, and fosfomycin disodium showed no inhibition of the reaction up to 20 mg/ml. However, other antibiotics, including penicillins, cephalosporins, macrolides, and tetracyclines, inhibited the reaction concentration dependently. Polymyxin B sulfate was the most potent inhibitor, with less than 8 micrograms/ml for 50% inhibition. It was concluded that the chromogenic method can be applied to the detection and determination of endotoxin in most of the antibiotic preparations. An application of this method to carbenicillin disodium preparations was exemplified. PMID:3700595

  6. Characterization of an aerosol chamber for human exposures to endotoxin.

    PubMed

    Taylor, L; Reist, P C; Boehlecke, B A; Jacobs, R R

    2000-03-01

    The objective of this study was to develop and characterize an exposure chamber in which human subjects could be exposed to low dust concentrations carrying an endotoxin coating. An exposure chamber, dust dispersion method, and endotoxin characterization technique were developed for inhalation exposures. A 6.27 m3 exposure chamber was designed and constructed from cinder block, glass windows, and Plexiglas. Using an acetone adhesion process, Enterobacter agglomerans were adsorbed onto respirable cellulose particles to create the endotoxin aerosol. The size distribution of the endotoxin-treated particles was verified using light microscopy and cascade impactors. A dry powder dust generator was refined to consistently disperse small quantities of the aerosol into the chamber to maintain dust concentrations at approximately 250 micrograms/m3. Dust levels during the chamber exposures were monitored using a portable continuous aerosol monitor (PCAM). During initial exposure runs, PCAM monitoring stations were positioned at different locations within a 0.5-meter matrix to document mixing patterns. Total dust and cascade impactor samples were collected throughout each exposure period to characterize the chamber operating system and insure the mean airborne dust concentration fulfilled target levels. A one-factor analysis of variance at the 95 percent confidence interval illustrated that there was not a statistically significant difference in the mean dust concentration throughout the exposure runs compared to the individual runs. Together the consistency of the total dust filters, endotoxin concentrations, and aerosol-monitoring instrument were adequate to allow use of the chamber for experimental studies involving human volunteers. PMID:10701293

  7. The interaction of human peripheral blood eosinophils with bacterial lipopolysaccharide is CD14 dependent.

    PubMed

    Plötz, S G; Lentschat, A; Behrendt, H; Plötz, W; Hamann, L; Ring, J; Rietschel, E T; Flad, H D; Ulmer, A J

    2001-01-01

    Bacterial lipopolysaccharide (LPS, endotoxin) is a ubiquitous component of dust and air pollution and is suspected to contribute after inhalation to an activation of eosinophils in bronchial tissues of asthmatic patients, provoking inflammatory and allergic processes. We were therefore interested in the interaction of eosinophil granulocytes with LPS and have examined the activation of and uptake to human peripheral blood eosinophils by LPS. Eosinophils were stimulated by LPS and the endotoxic component lipid A and the release of tumor necrosis factor alpha (TNF-alpha) and of the eosinophil-specific granule protein eosinophil cationic protein (ECP) was estimated. The results show induction of TNF-alpha and ECP-release by LPS and lipid A in a dose-dependent manner. Anti-CD14 monoclonal antibody (moAb) (clone MEM-18) and the synthetic lipid A partial structure 406 blocked the release of TNF-alpha and ECP by LPS-stimulated eosinophils. Studies with radioactively labeled LPS showed dose-dependent uptake of (3)H-LPS to eosinophils. The (3)H-LPS uptake was found to be specific because preincubation with unlabeled LPS, compound 406 and also anti-CD14 antibodies inhibited uptake of (3)H-LPS to eosinophil granulocytes. By flow cytometry using anti-CD14 moAb and by reverse transcriptase-polymerase chain reaction (RT-PCR) technique, CD14 expression was detectable. Furthermore, messenger RNA (mRNA) expression of Toll-like receptors (TLR) 2 and TLR 4 was detected, indicating the presence of these CD14 coreceptors. The results indicate that eosinophils can take up LPS and can be stimulated by LPS in a CD14-dependent manner. Hence, in addition to allergens, eosinophils interact with endotoxin, a process that possibly exacerbates ongoing inflammatory and allergic processes. PMID:11133766

  8. Lipopolysaccharide Does Not Alter Small Airway Reactivity in Mouse Lung Slices

    PubMed Central

    Donovan, Chantal; Royce, Simon G.; Vlahos, Ross; Bourke, Jane E.

    2015-01-01

    The bacterial endotoxin, lipopolysaccharide (LPS) has been associated with occupational airway diseases with asthma-like symptoms and in acute exacerbations of COPD. The direct and indirect effects of LPS on small airway reactivity have not been fully elucidated. We tested the hypothesis that both in vitro and in vivo LPS treatment would increase contraction and impair relaxation of mouse small airways. Lung slices were prepared from naïve Balb/C mice and cultured in the absence or presence of LPS (10 ?g/ml) for up to 48 h for measurement of TNF? levels in conditioned media. Alternatively, mice were challenged with PBS or LPS in vivo once a day for 4 days for preparation of lung slices or for harvest of lungs for Q-PCR analysis of gene expression of pro-inflammatory cytokines and receptors involved in airway contraction. Reactivity of small airways to contractile agonists, methacholine and serotonin, and bronchodilator agents, salbutamol, isoprenaline and rosiglitazone, were assessed using phase-contrast microscopy. In vitro LPS treatment of slices increased TNF? release 6-fold but did not alter contraction or relaxation to any agonists tested. In vivo LPS treatment increased lung gene expression of TNF?, IL-1? and ryanodine receptor isoform 2 more than 5-fold. However there were no changes in reactivity in lung slices from these mice, even when also incubated with LPS ex vivo. Despite evidence of LPS-induced inflammation, neither airway hyperresponsiveness or impaired dilator reactivity were evident. The increase in ryanodine receptor isoform 2, known to regulate calcium signaling in vascular smooth muscle, warrants investigation. Since LPS failed to elicit changes in small airway reactivity in mouse lung slices following in vitro or in vivo treatment, alternative approaches are required to define the potential contribution of this endotoxin to altered small airway reactivity in human lung diseases. PMID:25822969

  9. Granulocyte colony-stimulating factor exacerbates acute lung injury induced by intratracheal endotoxin in guinea pigs.

    PubMed

    Terashima, T; Kanazawa, M; Sayama, K; Ishizaka, A; Urano, T; Sakamaki, F; Nakamura, H; Waki, Y; Tasaka, S

    1994-05-01

    The effects of recombinant human granulocyte colony-stimulating factor (rG-CSF) on the lung injury induced by intratracheal endotoxin were studied using guinea pigs. Animals were divided into four groups: (1) saline control, (2) endotoxin alone, (3) cyclophosphamide (CPA)+endotoxin, and (4) CPA+rG-CSF+endotoxin. CPA was injected intraperitoneally to suppress hematopoietic function 7 d before the study. rG-CSF at a dose of 100 micrograms/kg was administered subcutaneously twice a day for 5 consecutive d beginning 2 d after the CPA pretreatment. Saline or 0.2 mg/kg of endotoxin was administered via the airway, and the animals were observed for 4 h. 99mTc-labeled macroaggregated albumin was mixed with saline or endotoxin to obtain a lobar distribution. Lung injury was assessed by the concentration ratio of 125I-labeled albumin in lung tissue to plasma (T/P) and lung wet-dry weight ratio (W/D). We also counted the number of neutrophils in bronchoalveolar lavage (BAL) fluid and fixed lung tissues. T/P, but not W/D, increased in endotoxin-alone and CPA+endotoxin groups compared with the saline control group (p < 0.01). Both T/P and W/D of the CPA+rG-CSF+endotoxin group were significantly higher than those of the endotoxin-alone and CPA+endotoxin groups (p < 0.01). In the CPA+rG-CSF+endotoxin group, histopathologic examination of the lung sections showed neutrophil recruitment into the lung, and neutrophil counts in BAL fluid were elevated. In conclusion, pretreatment with rG-CSF increased sequestration of neutrophils into the lung and exacerbated the lung injury induced by intratracheal endotoxin in CPA-treated guinea pigs. PMID:7513596

  10. Endotoxin inactivation via steam-heat treatment in dilute simethicone emulsions used in biopharmaceutical processes.

    PubMed

    Britt, Keith A; Galvin, Jeffrey; Gammell, Patrick; Nti-Gyabaah, Joseph; Boras, George; Kolwyck, David; Ramirez, José G; Presente, Esther; Naugle, Gregory

    2014-01-01

    Simethicone emulsion is used to regulate foaming in cell culture operations in biopharmaceutical processes. It is also a potential source of endotoxin contamination. The inactivation of endotoxins in dilute simethicone emulsions was assessed as a function of time at different steam temperatures using a Limulus amebocyte lysate kinetic chromogenic technique. Endotoxin inactivation from steam-heat treatment was fit to a four-parameter double exponential decay model, which indicated that endotoxin inactivation was biphasic, consisting of fast and slow regimes. In the fast regime, temperature-related effects were dominant. Transitioning into the slow regime, the observed temperature dependence diminished, and concentration-related effects became increasingly significant. The change in the Gibbs free energy moving through the transition state indicated that a large energy barrier must be overcome for endotoxin inactivation to occur. The corresponding Arrhenius pre-exponential factor was >10(12) s(-1) suggesting that endotoxins in aqueous solution exist as aggregates. The disorder associated with the endotoxin inactivation reaction pathway was assessed via the change in entropy moving through the transition state. This quantity was positive indicating that endotoxin inactivation may result from hydrolysis of individual endotoxin molecules, which perturbs the conformation of endotoxin aggregates, thereby modulating the biological activity observed. Steam-heat treatment decreased endotoxin levels by 1-2 logarithm (log) reduction (LRV), which may be practically relevant depending on incoming raw material endotoxin levels. Antifoam efficiency and cell culture performance were negligibly impacted following steam-heat treatment. The results from this study show that steam-heat treatment is a viable endotoxin control strategy that can be implemented to support large-scale biopharmaceutical manufacturing. PMID:24623631

  11. In vivo quantitation of the rat liver's ability to eliminate endotoxin from portal vein blood

    SciTech Connect

    Yamaguchi, Y.; Yamaguchi, K.; Babb, J.L.; Gans, H.

    1982-12-01

    The in vivo uptake of endotoxin by the liver from portal vein blood was assessed during a single passage through the liver. /sup 51/Cr labeled and unlabeled endotoxin were infused in different amounts into the femoral vein of three groups of lead-sensitized rats: a nonoperated, a sham-operated, and a surgically created reversed Eck fistula (REF) group. Whereas in the former two the infused endotoxin encounters the lung as the first filter organ, the liver performs this function in the latter experimental model. The mortality rates observed in control and sham-operated, lead-sensitized rats were found to correlate closely and reproducibly to the degree of endotoxemia. This assay was then applied to determine the amount of endotoxin eliminated by the liver by establishing, in the REF rat, the amounts of endotoxin that escaped hepatic clearance. The capacity of the liver to eliminate endotoxin from portal vein blood during a single passage increases as the portal vein endotoxin level rises; it approaches a maximum, suggesting that endotoxin's interaction with the Kupffer cells conforms to classical saturation kinetics. A Lineweaver-Burk plot prepared from these data indicates that the maximal in vivo capacity of the liver to remove endotoxin from portal vein blood approximates 1.5 micrograms/gm liver/hr. Data obtained with the use of radiolabeled endotoxin corroborate the information obtained with the bioassay technique. Endotoxin eliminated by the Kupffer cells in these quantities is slowly disintegrated; 4 hr after termination of the endotoxin infusion, less than 4% of the radiolabel is found in the urine and none in the bile. These observations indicate that the Kupffer cell's functional capacity to sequester and detoxify endotoxin is extensive and far exceeds the requirements imposed by physiological and most pathological conditions.

  12. Effects of recombinant human growth hormone on rat septic shock with intraabdominal infection by E. coli

    PubMed Central

    Huang, Ying; Wang, Shu-Ren; Yi, Cheng; Ying, Ming-Ying; Lin, Ying; Zhi, Mao-Hui

    2002-01-01

    AIM: To investigate the therapeutic effects of recombinant human growth hormone (rhGH) on rat septic shock with intraabdominal infection by E. coli and its possible mechanism. METHODS: 76 SD rats were divided into 3 groups randomly: control group (group C, n = 16) without any special treatment, septic shock group (group S, n = 30) received bolus injection of E.coli (1 × 1010 cfu·L-1,15 mL·kg-1, ip), treated group (group T, n = 30) received bolus injection of E.coli, and then followed by rhGH injection (2.25 U·kg-1·d-1, im). Group S and group T were further divided into 1d and 3d subgroups, respectively (n = 15 each). Mean arterial pressure (MAP), levels of plasma TNF? and endotoxin and leukocyte count were determined on 1st day and 3rd day after E.coli injection. Another 39 SD rats were divided into groups C, S and T (n = 13 each) just for observing survival rate within 1 week. RESULTS: (1) On 1st and 3rd day, MAP in group S decreased markedly, and MAP on 1st day lowered more than that of 3rd day (P < 0.01), while MAP in group T just decreased slightly. The survival rate within 1 week was much higher in group T (84.6%) than in group S (46.2%) (P < 0.01). (2)On 1st day, plasma TNF? and endotoxin elevated significantly in group S and group T (P < 0.05), and endotoxin in group S had more increase (P < 0.01). On 3rd day, TNF? in group S returned to the level of group C (P > 0.05),while TNF? in group T went down below the level of group C(P < 0.01). On 3rd day, endotoxin in group S declined, but was still higher than that of group C (P < 0.01), endotoxin in group T returned to the level of group C (P > 0.05). (3) On 1st day, neutrophil ratio in total leukocyte count in both group S and group T increased significantly (P < 0.05 vs group C). CONCLUSION: rhGH showed beneficial effects on rat septic shock. The possible mechanisms may involve the attenuation of bacteria/endotoxin translocation and decreased systemic endotoxin level; inhibition of the production and release of TNF?; improved circulatory function; improved systemic host defenses and maintenance of intestinal mucosa barrier. PMID:12439940

  13. Effect of resveratrol, a natural polyphenolic compound, on platelet activation induced by endotoxin or thrombin.

    PubMed

    Olas, Beata; Wachowicz, Barbara; Saluk-Juszczak, Joanna; Zieli?ski, Tomasz

    2002-08-15

    Resveratrol (3, 4', 5-trihydroxystilbene), a natural polyphenol, is found in some plants that are used in human nutrition. Grapes are a major source for resveratrol, and a significant amount can also be found in red wine. Several experimental studies have demonstrated biological properties of resveratrol, especially its anti-inflammatory, antioxidant, anti-platelet and antitumor effects. In the present study, we investigated the first step of platelet activation-platelet adhesion stimulated by lipopolysaccharide (LPS) from Proteus mirabilis (weak stimulator) and thrombin (strong activator) in the presence of resveratrol. Our studies show that endotoxin (0.3 microg/10(8) platelets), like thrombin (0.2 U/10(8) platelets), induced the adhesion of platelets (expressed as absorbance of cell attached proteins) to collagen and fibrinogen. Preincubation of washed platelets with resveratrol at physiological plasma concentrations (25-100 microg/ml, 30 min, 37 degrees C) had an inhibitory effect on adhesion of platelets to collagen after activation by LPS alone or LPS with thrombin. The strongest effect on this process was caused by resveratrol at the concentration of 100 microg/ml. Pretreatment of platelets with resveratrol (25-100 microg/ml, 30 min, 37 degrees C) had also inhibitory effects on adhesion of platelets to fibrinogen after stimulation of these cells by LPS alone or by LPS with thrombin at the same concentration. In conclusion, we suggest that resveratrol present in human diet may be an important compound responsible for the reduction of platelet adhesion and changed reactivity of blood platelets in inflammatory process. PMID:12431480

  14. Green Tea Extract Treatment Alleviates Ocular Inflammation in a Rat Model of Endotoxin-Induced Uveitis

    PubMed Central

    Qin, Yong Jie; Chu, Kai On; Yip, Yolanda Wong Ying; Li, Wai Ying; Yang, Ya Ping; Chan, Kwok Ping; Ren, Jia Lin

    2014-01-01

    Green tea extract (GTE) ingested by rats exerted anti-oxidative activities in various ocular tissues as shown in our previous studies. The present work investigated anti-inflammatory effects of GTE on endotoxin-induced uveitis (EIU). EIU was generated in adult rats by a footpad injection of 1 mg/kg lipopolysaccharide (LPS). Oral administration of GTE (550 mg/kg) was given one, two or four times after LPS injection. Twenty-four hours later, LPS produced severe hyperemia and edema in the iris. Immunocytochemical examinations showed an accumulation of infiltrating cells in the aqueous humor that were immunopositive for cluster of differentiation 43 (CD43) and CD68, markers for leucocytes and macrophages, respectively. Analyses of the aqueous humor showed an increase in pro-inflammatory mediators including tumor necrosis factor-alpha (TNF-?), interleukin-6 (IL-6) and monocyte chemoattractant protein-1 (MCP-1). GTE treatments improved the clinical manifestations and reduced infiltrating cells and protein exudation in the aqueous humor, which were not observed under half dose of GTE (275 mg/kg). The number of CD68 positive macrophages residing in the iris and ciliary was also reduced. GTE suppressed production of TNF-?, IL-6 and MCP-1 in the aqueous humor, which was associated with a down-regulation of LPS receptor complex subunits, Toll-like receptor 4 (TLR-4) and CD14, and suppression of nuclear factor-kappa Bp65 (NF-?Bp65) in the iris and ciliary body. Our findings show that GTE is a potent anti-inflammatory agent against the inflammation of EIU, and suggest a potential use in treatment of acute uveitis. PMID:25093862

  15. Distribution and composition of lipopolysaccharides from mycoplasmas.

    PubMed Central

    Smith, P F; Langworthy, T A; Mayberry, W R

    1976-01-01

    Polymeric carbohydrates containing glycerol and fatty acids were isolated from whole cells and membranes of mycoplasmas by hot aqueous phenol extraction and gel filtration. Lipopolysaccharides were found to occur in four species of Acholeplasma, two of Anaeroplasma, and in Mycoplasma neurolyticum. None were detected in Spiroplasma citri or in five species of Mycoplasma. All lipopolysaccharides contained both neutral and N-acylated amino sugars in ratios varying from 1:1 to 3:1. The neutral sugars found in varying distribution were glucose, galactose, and mannose. The amino sugars included fucosamine, an unidentified deoxyhexosamine, galactosamine, and glucosamine. Fucosamine and glucose were the only sugars common to all lipopolysaccharides. The fatty acids were similar to those found in the lipids of each organism. PMID:1254559

  16. Lipopolysaccharides of Brucella abortus and Brucella melitensis Induce Nitric Oxide Synthesis in Rat Peritoneal Macrophages

    PubMed Central

    López-Urrutia, Luis; Alonso, Andrés; Nieto, Maria Luisa; Bayón, Yolanda; Orduña, Antonio; Sánchez Crespo, Mariano

    2000-01-01

    Smooth lipopolysaccharide (S-LPS) and lipid A of Brucella abortus and Brucella melitensis induced the production of nitric oxide (NO) by rat adherent peritoneal cells, but they induced lower levels of production of NO than Escherichia coli LPS. The participation of the inducible isoform of NO synthase (iNOS) was confirmed by the finding of an increased expression of both iNOS mRNA and iNOS protein. These observations might help to explain (i) the acute outcome of Brucella infection in rodents, (ii) the low frequency of septic shock in human brucellosis, and (iii) the prolonged intracellular survival of Brucella in humans. PMID:10679001

  17. Use of indium-111 oxine to study pulmonary and hepatic leukocyte sequestration in endotoxin shock and effects of the beta-2 receptor agonist terbutaline

    SciTech Connect

    Sigurdsson, G.H.; Christenson, J.T.; al-Mousawi, M.; Owunwanne, A. )

    1989-01-01

    The dynamic behavior of indium-111 oxine-labeled leukocytes was simultaneously recorded in multiple organs during endotoxin shock in sheep. Also, the effects of the beta-2 receptor agonist terbutaline were studied. An experimental protocol was designed to mimic a clinical condition in an intensive care setting as far as possible. The animals were ventilated with 50% oxygen to avoid hypoxemia and were given large amounts of intravenous fluids to reduce adverse effects of hypovolemia. A moderate dose of E. coli endotoxin (10 micrograms/kg bwt) was given by intravenous infusion to 14 adult sheep, seven of them receiving continuous intravenous infusion of terbutaline (20 micrograms/kg/hr) during 4 hr, starting 30 min after endotoxin, when signs of lung injury had developed. The other seven acted as controls. A marked pulmonary and hepatic leukocyte sequestration together with a sharp drop in leukocyte counts in peripheral blood occurred within minutes after start of the endotoxin infusion in both groups. However, no changes were observed in the kidneys or the gut. After 60 min and until the end of the experiment, there was a significantly lower activity in the lungs and in the liver of the animals treated with terbutaline than in the controls (P less than .01). Furthermore, less marked hemodynamic and respiratory alterations occurred in the terbutaline group compared with the controls. This study confirms the results of other investigators showing that significant leukocyte sequestration occurs in the lungs during endotoxemia, but it also demonstrates that leukocytes sequestrate in the liver, although slightly less than in the lungs.

  18. Adhesion of a human fecal Escherichia coli strain to mouse colonic mucus.

    PubMed Central

    Cohen, P S; Arruda, J C; Williams, T J; Laux, D C

    1985-01-01

    Escherichia coli F-18 isolated from the feces of a healthy human is an excellent colonizer of the CD-1 mouse colon. In the present investigation, adhesion of E. coli F-18 to CD-1 mouse colonic mucus and bovine serum albumin (BSA), immobilized on polystyrene, was studied. Adhesion of E. coli F-18 to mucus was two- to sixfold greater than to either BSA or polystyrene. E. coli F-18 lipopolysaccharide specifically blocked adhesion of E. coli F-18 to mucus and mimicked adhesion of E. coli F-18 to mucus, BSA, and polystyrene. Purified capsule also blocked adhesion of E. coli F-18 to mucus, but this inhibition was found to be entirely nonspecific. The specific E. coli F-18 receptor in mucus appeared to be a glycoprotein, containing sugars normally found in mucins and having a maximum molecular weight of between 1.25 X 10(5) and 2.5 X 10(5). PMID:3920146

  19. Endotoxin levels at Swine farms using different waste treatment and management technologies.

    PubMed

    Ko, Gwangpyo; Simmons Iii, Otto D; Likirdopulos, Christina A; Worley-Davis, Lynn; Williams, C M; Sobsey, Mark D

    2010-05-01

    Concentrated animal feeding operations (CAFOs) are a major source of airborne endotoxins, which are air pollutants that can cause adverse health effects to both on-site farmers and neighbors. Release of airborne endotoxins to the environment can be reduced using proper waste treatment and management technologies. In this study, the levels of endotoxins released from two swine CAFOs using conventional lagoon-sprayfield technology were compared to those of 15 farms using various alternative waste management technologies in North Carolina. Over a 2-year period, 236 endotoxin samples were collected from the 17 farm units and analyzed using the Limulus amebocyte lysate (LAL) test. Concentrations of airborne endotoxins near barn exhaust fans were significantly higher than at the upwind boundary of the farm and at other farm sites. For most of the study sites, mean concentrations of endotoxins at the downwind boundary of the farm were higher than those at the upwind boundary of the farm, indicating the release of endotoxins from swine CAFOs to the neighboring environment. Endotoxin levels were significantly associated with concentrations of airborne bacteria but not fungi. Environmental factors, such as temperature, relative humidity, and wind velocity, affected the levels of airborne endotoxins at the farms. Based on the ratios of airborne endotoxins in downwind and upwind samples from the farm units, at least five different alternative waste management technologies significantly reduced the release of endotoxins from swine CAFOs. These results suggest that swine CAFOs are important sources of airborne endotoxins, the levels of which can be reduced by applying more robust and effective waste management technologies. PMID:20356077

  20. Prostaglandins mediate lipopolysaccharide effects upon cholecystokinin and neurotensin phenotypes in neuroendocrine corticotropin-releasing hormone neurons: in situ hybridization evidence in the rat.

    PubMed

    Ribot, E; Lafon, P; Ciofi, P; Sarrieau, A; Tramu, G; Corio, M

    2003-01-01

    Intraperitoneal injection of the endotoxin lipopolysaccharide produces an inflammation accompanied by immune system activation and secretion of cytokines that stimulate the hypothalamo-pituitary-adrenal (HPA) axis to release the anti-inflammatory corticosterone. Upstream in HPA axis are neuroendocrine corticotropin-releasing hormone neurons in the paraventricular nucleus whose multipeptidergic phenotype changes during inflammation: coexisting corticotropin-releasing hormone and cholecystokinin mRNAs are up-regulated whereas neurotensin mRNA expression is induced de novo. These changes may be mediated by prostaglandins released from perivascular and microglial cells in response to circulating cytokines. We examined by quantitative in situ hybridization histochemistry whether blockade of prostaglandin synthesis by indomethacin alters phenotypic expression in paraventricular nucleus neurons after lipopolysaccharide. Because indomethacin also elevated circulating corticosterone, animals were adrenalectomized and corticosterone replaced. Results showed that i.p. indomethacin administration suppressed lipopolysaccharide effects in a phenotype non-specific manner: one injection was sufficient to prevent both the increase in corticotropin-releasing hormone and cholecystokinin mRNAs expression and the induction of neurotensin mRNA expression. Therefore, neuroendocrine corticotropin-releasing hormone neurons with different peptidergic phenotypes appear to respond as a whole in the acute phase response to systemic infection. PMID:12895505

  1. Comparison of endotoxin levels in cow's milk samples derived from farms and shops.

    PubMed

    Sipka, Sándor; Béres, Andrea; Bertók, Lóránd; Varga, Tamara; Bruckner, Geza

    2015-07-01

    The observations on the protective effect of bacterial endotoxin in farm-derived cow's milk on childhood asthma and allergy are contradictory. The aim of this study was to determine the endotoxin levels in 'farm-derived whole raw' and 'processed shop' sources of cow's milk, and to test how the temperature and storing conditions might alter their endotoxin concentrations. Milk was collected from farms and shops. The level of endotoxin was measured by micro (gel-clot) Limulus amebocyte lysate test expressed as EU/ml. The concentration ranges of endotoxin were much higher and more widely scattered in the samples of whole raw farm milk than in the processed shop milk. Cold storage or heating increased the endotoxin concentrations in all samples of farm milk, but not in the processed shop milk. These results show that elevated levels of endotoxin in raw farm milk samples can occur from the cowshed or be formed during storage. In processed shop milk, storage does not cause any changes in the amount of endotoxin. Therefore, it is consistent that the handling and storage of raw milk alters the endotoxin concentrations, which may explain previous contradictory findings regarding the beneficial modulating effects on innate immunity toward allergy prevention in early childhood. PMID:25527628

  2. Detection of bacterial endotoxin in drinking tap and bottled water in Kuwait.

    PubMed

    Abdulraheem, Abdulkareem; Mustafa, Seham; Al-Saffar, Nabeel; Shahjahan, Muhammed

    2012-12-01

    This study was carried out to measure and compare the concentration of bacterial endotoxin in a variety of samples from drinking tap and bottled water available in Kuwait by using the Limulus Amoebocyte lysate test. A total of 29 samples were tested. Samples were collected from a variety of locations throughout the six governorates of Kuwait and 23 brands of local and imported bottled water samples were collected from the local market. The concentration of bacterial endotoxin was measured by using the standard Limulus Amoebocyte lysate test, gel clot method. This study showed that measured endotoxin concentrations in tap drinking water varied from 2.4 to 33.8 EU/ml with the average endotoxin concentration of 14.2 EU/ml. While the results of endotoxin concentrations in the bottled water were <0.03 to 20.1 EU/ml with an average of 1.96 EU/ml. The average concentration of endotoxin in bottled water is 13.5 % of the average concentration of endotoxin in tap drinking water. This experimental investigation has proved that drinking bottled water has less endotoxin as compared to tap water in Kuwait. It is also demonstrated that the endotoxin concentration did not exceed the acceptable level in drinking tap water. PMID:22270589

  3. [Endotoxin adsortion as adjuvant therapy in gram negative severe sepsis].

    PubMed

    Candel, F J; Martínez-Sagasti, F; Borges, M; Maseda, E; Herrera-Gutiérrez, M; Garnacho-Montero, J; Maynar, F J; Zaragoza, R; Mensa, J; Azanza, J R

    2010-09-01

    The mortality rate of severe sepsis and septic shock remains still high. Within the last years a better knowledge of its physiopathology and the implementation of a group of measures addressed to a fast identification and early treatment of the septic patients have proved to reduce mortality rate. Likewise, it continues being investigated in modulating the inflammatory response and limiting the harmful action of the bacterial products on the immune system. As a result of this research some endotoxin adsorber devices have been designed to control one of the most important targets that start the inflammatory cascade when gram negative microorganisms are involved.The usefulness that these endotoxin removal devices might have as adjuvant treatment in the Septic Syndrome and its applicability are reviewed in this paper. Likewise a profile of patient that might be to the benefit of this therapy is suggested according to the current knowledge. PMID:20844841

  4. Functional and fine structural changes in isolated rat lungs challenged with endotoxin ex vivo and in vitro.

    PubMed Central

    Uhlig, S.; Brasch, F.; Wollin, L.; Fehrenbach, H.; Richter, J.; Wendel, A.

    1995-01-01

    The aim of this study was to relate changes in rat lung functions caused by the endotoxin lipopolysaccharide (LPS) to alterations in structure. The following four experimental groups were used: 1), control in vitro, perfusion for 150 minutes; 2), LPS in vitro, perfusion for 150 minutes and infusion of 5 mg of LPS after 40 minutes; 3), control ex vivo, perfusion for 10 minutes; and 4), LPS ex vivo, lungs perfused for 10 minutes from rats treated for 110 minutes with 20 mg/kg LPS intraperitoneally. Histologically, blood-derived leukocytes were detectable only in lungs from group 4, where neutrophils were found in capillaries, interstitium, and endothelial pouches. LPS treatment increased pulmonary resistance and decreased pulmonary compliance in group 4 (ex vivo), and, to a greater extent, in group 2 (in vitro). In these two groups, formation of giant lamellar bodies in the type II pneumocytes was observed. By histological examination, the bronchoconstriction induced by LPS in vitro was localized to the terminal bronchioles. At 2 hours after LPS treatment, no edema and no change in precapillary and postcapillary resistance, capillary pressure, vascular compliance, capillary permeability, and the wet/dry ratio was observed. Thus, our major findings are that LPS induced constriction of the terminal bronchioles in vitro, formation of giant lamellar bodies in type II pneumocytes ex vivo and in vitro, and trapping of neutrophils in endothelial pouches in vivo. Images Figure 2 Figure 3 Figure 4 Figure 6 PMID:7747816

  5. Inhibition of oxidative stress and cytokine activity by curcumin in amelioration of endotoxin-induced experimental hepatoxicity in rodents

    PubMed Central

    Kaur, G; Tirkey, N; Bharrhan, S; Chanana, V; Rishi, P; Chopra, K

    2006-01-01

    Summary The present study is aimed at investigating the effect of curcumin (CMN) in salvaging endotoxin-induced hepatic dysfunction and oxidative stress in the liver of rodents. Hepatotoxicity was induced by administering lipopolysaccharide (LPS) in a single dose of 1 mg/kg intraperitoneally to the animals, which were being treated with CMN daily for 7 days. Liver enzymes serum alanine aminotransferase (ALT), serum aspartate aminotransferase (AST) and alkaline phosphatase (ALP), total bilirubin and total protein were estimated in serum. Oxidative stress in liver tissue homogenates was estimated by measuring thiobarbituric acid reactive substances (TBARS), glutathione (GSH) content and superoxide dismutase (SOD) activity. Serum and tissue nitrite was estimated using Greiss reagent and served as an indicator of NO production. A separate set of experiments was performed to estimate the effect of CMN on cytokine levels in mouse serum after LPS challenge. LPS induced a marked hepatic dysfunction evident by rise in serum levels of ALT, AST, ALP and total bilirubin (P < 0·05). TBARS levels were significantly increased, whereas GSH and SOD levels decreased in the liver homogenates of LPS-challenged rats. CMN administration attenuated these effects of LPS successfully. Further CMN treatment also regressed various structural changes induced by LPS in the livers of rats and decreased the levels of tumour necrosis factor-? and interleukin-6 in mouse plasma. In conclusion, these findings suggest that CMN attenuates LPS-induced hepatotoxicity possibly by preventing cytotoxic effects of NO, oxygen free radicals and cytokines. PMID:16879252

  6. Endotoxin-induced basal respiration alterations of renal HK-2 cells: A sign of pathologic metabolism down-regulation

    SciTech Connect

    Quoilin, C.; Mouithys-Mickalad, A.; Duranteau, J.; Gallez, B.; Hoebeke, M.

    2012-06-29

    Highlights: Black-Right-Pointing-Pointer A HK-2 cells model of inflammation-induced acute kidney injury. Black-Right-Pointing-Pointer Two oximetry methods: high resolution respirometry and ESR spectroscopy. Black-Right-Pointing-Pointer Oxygen consumption rates of renal cells decrease when treated with LPS. Black-Right-Pointing-Pointer Cells do not recover normal respiration when the LPS treatment is removed. Black-Right-Pointing-Pointer This basal respiration alteration is a sign of pathologic metabolism down-regulation. -- Abstract: To study the mechanism of oxygen regulation in inflammation-induced acute kidney injury, we investigate the effects of a bacterial endotoxin (lipopolysaccharide, LPS) on the basal respiration of proximal tubular epithelial cells (HK-2) both by high-resolution respirometry and electron spin resonance spectroscopy. These two complementary methods have shown that HK-2 cells exhibit a decreased oxygen consumption rate when treated with LPS. Surprisingly, this cellular respiration alteration persists even after the stress factor was removed. We suggested that this irreversible decrease in renal oxygen consumption after LPS challenge is related to a pathologic metabolic down-regulation such as a lack of oxygen utilization by cells.

  7. Lipid Lateral Organization on Giant Unilamellar Vesicles Containing Lipopolysaccharides

    PubMed Central

    Kubiak, Jakubs; Brewer, Jonathan; Hansen, Søren; Bagatolli, Luis A.

    2011-01-01

    We developed a new (to our knowledge) protocol to generate giant unilamellar vesicles (GUVs) composed of mixtures of single lipopolysaccharide (LPS) species and Escherichia coli polar lipid extracts. Four different LPSs that differed in the size of the polar headgroup (i.e., LPS smooth > LPS-Ra > LPS-Rc > LPS-Rd) were selected to generate GUVs composed of different LPS/E. coli polar lipid mixtures. Our procedure consists of two main steps: 1), generation and purification of oligolamellar liposomes containing LPSs; and 2), electroformation of GUVs using the LPS-containing oligolamellar vesicles at physiological salt and pH conditions. Analysis of LPS incorporation into the membrane models (both oligolamellar vesicles and GUVs) shows that the final concentration of LPS is lower than that expected from the initial E. coli lipids/LPS mixture. In particular, our protocol allows incorporation of no more than 15 mol % for LPS-smooth and LPS-Ra, and up to 25 mol % for LPS-Rc and LPS-Rd (with respect to total lipids). We used the GUVs to evaluate the impact of different LPS species on the lateral structure of the host membrane (i.e., E. coli polar lipid extract). Rhodamine-DPPE-labeled GUVs show the presence of elongated micrometer-sized lipid domains for GUVs containing either LPS-Rc or LPS-Rd above 10 mol %. Laurdan GP images confirm this finding and show that this particular lateral scenario corresponds to the coexistence of fluid disordered and gel (LPS-enriched)-like micron-sized domains, in similarity to what is observed when LPS is replaced with lipid A. For LPSs containing the more bulky polar headgroup (i.e., LPS-smooth and LPS-Ra), an absence of micrometer-sized domains is observed for all LPS concentrations explored in the GUVs (up to ?15 mol %). However, fluorescence correlation spectroscopy (using fluorescently labeled LPS) and Laurdan GP experiments in these microscopically homogeneous membranes suggests the presence of LPS clusters with dimensions below our microscope's resolution (?380 nm radial). Our results indicate that LPSs can cluster into gel-like domains in these bacterial model membranes, and that the size of these domains depends on the chemical structure and concentration of the LPSs. PMID:21320442

  8. Pantoea agglomerans: a marvelous bacterium of evil and good.Part I. Deleterious effects: Dust-borne endotoxins and allergens - focus on cotton dust.

    PubMed

    Dutkiewicz, Jacek; Mackiewicz, Barbara; Lemieszek, Marta Kinga; Golec, Marcin; Milanowski, Janusz

    2015-12-13

    The ubiquitous Gram-negative bacterium Pantoea agglomerans (synonyms: Enterobacter agglomerans, Erwinia herbicola) is known both as an epiphytic microbe developing on the surface of plants and as an endophytic organism living inside the plants. The bacterium occurs also abundantly in plant and animal products, in the body of arthropods and other animals, in water, soil, dust and air, and occasionally in humans. From the human viewpoint, the role of this organism is ambiguous, both deleterious and beneficial: on one side it causes disorders in people exposed to inhalation of organic dusts and diseases of crops, and on the other side it produces substances effective in the treatment of cancer and other diseases of humans and animals, suppresses the development of various plant pathogens, promotes plant growth, and appears as a potentially efficient biofertilizer and bioremediator. P. agglomerans was identified as a predominant bacterium on cotton plant grown all over the world, usually as an epiphyte, rarely as pathogen. It is particularly numerous on cotton bract after senescence. During processing of cotton in mills, bacteria and their products are released with cotton dust into air and are inhaled by workers, causing respiratory and general disorders, usually defined as byssinosis. The most adverse substance is endotoxin, a heteropolymer macromolecule present in the outermost part of the cell wall, consisting of lipopolysaccharide (LPS) as a major constituent, phospholipids and protein. The numerous experiments carried out in last quarter of XXth century on laboratory animals and human volunteers supported a convincing evidence that the inhaled endotoxin produced by P. agglomerans causes numerous pathologic effects similar to those elicited by cotton dust, such as influx of free lung cells into airways and activation of alveolar macrophages which secrete mediators (prostaglandins, platelet-activating factor, interleukin-1, tumor necrosis factor) that cause accumulation of platelets in pulmonary capillaries initiating an acute and chronic inflammation resulting in endothelial cell damage and extravasation of cells and fluids into the lung interstitium. These changes cause bronchoconstriction, the decrement of lung function expressed as reduction of forced expiratory volume in one second (FEV1) and/or diffusion capacity, increase in the airway hyperreactivity and subjective symptoms such as fever, airway irritation and chest tightness. The conclusions from these experiments, performed mostly 2-3 decades ago, did not loose their actuality until recently as so far no other cotton dust component was identified as a more important work-related hazard than bacterial endotoxin. Though also other microbial and plant constituents are considered as potential causative agents of byssinosis, the endotoxin produced by Pantoea agglomerans and other Gram-negative bacteria present in cotton dust is still regarded as a major cause of this mysterious disease. PMID:26706959

  9. Detection of endotoxins and other pyrogens using human whole blood.

    PubMed

    Fennrich, S; Fischer, M; Hartung, T; Lexa, P; Montag-Lessing, T; Sonntag, H G; Weigandt, M; Wendel, A

    1999-01-01

    When cells of the immune system, i.e. primarily blood monocytes and macrophages, come into contact with pyrogens (fever-inducing contaminations) they release mediators transmitting the fever reaction through the organism to the thermoregulatory centres of the brain. The new test discussed here exploits this reaction for the detection of pyrogens: human whole blood taken from healthy volunteers is incubated in the presence of the test sample. If there is pyrogen contamination, the endogenous pyrogen interleukin-1 is released, which is then determined by ELISA. According to the pharmacopoeia, the rabbit pyrogen test determines the fever reaction following injection of a test sample. In comparison, the new whole blood assay is more sensitive, less expensive and determines the reaction of the targeted species. Compared to the well established in vitro alternative, i.e. the limulus amebocyte lysate assay (LAL), the new blood assay is not restricted to endotoxins of gram-negative bacteria, it is not affected by endotoxin-binding blood proteins and it reflects the potency of different endotoxin preparations in mammals. Here, interim results of the ongoing optimization and pre-validation are reported and the present state of the evaluation for biological and pharmaceutical drugs are presented. PMID:10566786

  10. A new limulus assay for the detection of endotoxin.

    PubMed

    Harris, N S; Feinstein, R

    1977-09-01

    The limulus amebocyte lysate (LAL) assay has proven to be a highly sensitive and reliable indicator of endotoxin in most biological fluids; however, it has not been a reliable indicator when used with blood because of different inhibitors present in the blood. To avoid these problems, investigators have used difficult extraction procedures, but but even with these, results were oftentimes not uniform. It was found that a recently developed inert polymer (PSI-HAP 100) has a specific affinity for endotoxin, so that is was possible to develop a simple, reliable, reproducible method for the detection of endotoxin in blood. In the assay procedure, the polymer, compressed into a 3-mm diameter bead, is incubated with 0.2 cc of heparinized whole blood. The bead is then removed from the blood, washed in pyrogen-free saline to remove any inhibitors of the LAL, and placed in a tube containing LAL. The LAL and bead are incubated together; after incubation the LAL is examined for gellation. Using this new method, it was possible to predict Gram-negative septic episodes in burn patients several days before sepsis evolved clinically. PMID:894761

  11. Airborne Endotoxin from Indoor and Outdoor Environments:Effect of Sample Dilution on the Kinetic Limulus Amebocyte Lysate (LAL) Assay

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Airborne endotoxin in occupational environments are a potential respiratory hazard to individuals. In this study, total and inhalable airborne endotoxin samples were collected via filtration from inside animal housing units and downwind from agricultural production sites and a wastewater treatment ...

  12. E. coli

    MedlinePLUS

    ... Salmonella Shigella Staphylococcus Vibrio Infections Parasites Allergens Molds, Toxins and Contaminants Long-Term Effects How Government Responds ... even death. E. coli O157:H7 makes a toxin called Shiga toxin and is known as a ...

  13. The Effect of Residual Endotoxin Contamination on the Neuroinflammatory Response to Sterilized Intracortical Microelectrodes.

    PubMed

    Ravikumar, Madhumitha; Hageman, Daniel J; Tomaszewski, William H; Chandra, Gabriella M; Skousen, John L; Capadona, Jeffrey R

    2014-05-01

    A major limitation to the use of microelectrode technologies in both research and clinical applications is our inability to consistently record high quality neural signals. There is increasing evidence that recording instability is linked, in part, to neuroinflammation. A number of factors including extravasated blood products and macrophage released soluble factors are believed to mediate neuroinflammation and the resulting recording instability. However, the roles of other inflammatory stimuli, such as residual endotoxin contamination, are poorly understood. Therefore, to determine the effect of endotoxin contamination we examined the brain tissue response of C57/BL6 mice to non-functional microelectrodes with a range of endotoxin levels. Endotoxin contamination on the sterilized microelectrodes was measured using a limulus amebocyte lysate test following FDA guidelines. Microelectrodes sterilized by autoclave, dry heat, or ethylene oxide gas, resulted in variable levels of residual endotoxins of 0.55 EU/mL, 0.22 EU/mL, and 0.11 EU/mL, respectively. Histological evaluation at two weeks showed a direct correlation between microglia/macrophage activation and endotoxin levels. Interestingly, astrogliosis, neuronal loss, and blood brain barrier dysfunction demonstrated a threshold-dependent response to bacterial endotoxins. However, at sixteen weeks, no histological differences were detected, regardless of initial endotoxin levels. Therefore, our results demonstrate that endotoxin contamination, within the range examined, contributes to initial but not chronic microelectrode associated neuroinflammation. Our results suggest that minimizing residual endotoxins may impact early recording quality. To this end, endotoxins should be considered as a potent stimulant to the neuroinflammatory response to implanted intracortical microelectrodes. PMID:24778808

  14. The Effect of Residual Endotoxin Contamination on the Neuroinflammatory Response to Sterilized Intracortical Microelectrodes

    PubMed Central

    Ravikumar, Madhumitha; Hageman, Daniel J.; Tomaszewski, William H.; Chandra, Gabriella M.; Skousen, John L.; Capadona, Jeffrey R.

    2014-01-01

    A major limitation to the use of microelectrode technologies in both research and clinical applications is our inability to consistently record high quality neural signals. There is increasing evidence that recording instability is linked, in part, to neuroinflammation. A number of factors including extravasated blood products and macrophage released soluble factors are believed to mediate neuroinflammation and the resulting recording instability. However, the roles of other inflammatory stimuli, such as residual endotoxin contamination, are poorly understood. Therefore, to determine the effect of endotoxin contamination we examined the brain tissue response of C57/BL6 mice to non-functional microelectrodes with a range of endotoxin levels. Endotoxin contamination on the sterilized microelectrodes was measured using a limulus amebocyte lysate test following FDA guidelines. Microelectrodes sterilized by autoclave, dry heat, or ethylene oxide gas, resulted in variable levels of residual endotoxins of 0.55 EU/mL, 0.22 EU/mL, and 0.11 EU/mL, respectively. Histological evaluation at two weeks showed a direct correlation between microglia/macrophage activation and endotoxin levels. Interestingly, astrogliosis, neuronal loss, and blood brain barrier dysfunction demonstrated a threshold-dependent response to bacterial endotoxins. However, at sixteen weeks, no histological differences were detected, regardless of initial endotoxin levels. Therefore, our results demonstrate that endotoxin contamination, within the range examined, contributes to initial but not chronic microelectrode associated neuroinflammation. Our results suggest that minimizing residual endotoxins may impact early recording quality. To this end, endotoxins should be considered as a potent stimulant to the neuroinflammatory response to implanted intracortical microelectrodes. PMID:24778808

  15. Molecular mechanism underlying persistent induction of LCN2 by lipopolysaccharide in kidney fibroblasts.

    PubMed

    Glaros, Trevor; Fu, Yan; Xing, Jianhua; Li, Liwu

    2012-01-01

    The neutrophil gelatinase-associated lipocalin 2 (LCN2) is a critical inflammatory mediator persistently induced during endotoxemia, contributing to tubular damage and kidney failure. The intracellular process responsible for persistent induction of LCN2 by bacterial endotoxin Lipopolysaccharide (LPS) is not well understood. Using primary kidney fibroblasts, we observed that LPS-induced LCN2 expression requires a coupled circuit involving an early transient phase of AP-1 path and a late persistent phase of C/EBP? path, both of which are dependent upon the interleukin 1 receptor associated kinase 1 (IRAK-1). Using immunoprecipitation analysis we observed transient binding of AP-1 to the promoters of both TNF? and C/ebp?. On the other hand, we only observed persistent binding of C/EBP? to its own promoter but not on TNF?. Blockage of new protein synthesis using cyclohexamide significantly reduced the expression of C/EBP? as well as LCN2. By chromatin immunoprecipitation analyses, we demonstrated that LPS recruited C/EBP? to the Lcn2 promoter in WT, but not IRAK-1 deficient fibroblasts. A differential equation-based computational model captured the dynamic circuit leading to the persistent induction of LCN2. In vivo, we observed elevated levels of LCN2 in kidneys harvested from LPS-injected WT mice as compared to IRAK-1 deficient mice. Taken together, this study has identified an integrated intracellular network involved in the persistent induction of LCN2 by LPS. PMID:22514649

  16. Zinc Prevents Sickness Behavior Induced by Lipopolysaccharides after a Stress Challenge in Rats

    PubMed Central

    Kirsten, Thiago B.; Galvão, Marcella C.; Reis-Silva, Thiago M.; Queiroz-Hazarbassanov, Nicolle; Bernardi, Maria M.

    2015-01-01

    Sickness behavior is considered part of the specific beneficial adaptive behavioral and neuroimmune changes that occur in individuals in response to infectious/inflammatory processes. However, in dangerous and stressful situations, sickness behavior should be momentarily abrogated to prioritize survival behaviors, such as fight or flight. Taking this assumption into account, we experimentally induced sickness behavior in rats using lipopolysaccharides (LPS), an endotoxin that mimics infection by gram-negative bacteria, and then exposed these rats to a restraint stress challenge. Zinc has been shown to play a regulatory role in the immune and nervous systems. Therefore, the objective of this study was to examine the effects of zinc treatment on the sickness response of stress-challenged rats. We evaluated 22-kHz ultrasonic vocalizations, open-field behavior, tumor necrosis factor ? (TNF-?), corticosterone, and brain-derived neurotrophic factor (BDNF) plasma levels. LPS administration induced sickness behavior in rats compared to controls, i.e., decreases in the distance traveled, average velocity, rearing frequency, self-grooming, and number of vocalizations, as well as an increase in the plasma levels of TNF-?, compared with controls after a stressor challenge. LPS also decreased BDNF expression but did not influence anxiety parameters. Zinc treatment was able to prevent sickness behavior in LPS-exposed rats after the stress challenge, restoring exploratory/motor behaviors, communication, and TNF-? levels similar to those of the control group. Thus, zinc treatment appears to be beneficial for sick animals when they are facing risky/stressful situations. PMID:25775356

  17. Dynamic modulation of innate immune response by varying dosages of lipopolysaccharide (LPS) in human monocytic cells.

    PubMed

    Morris, Matthew C; Gilliam, Elizabeth A; Button, Julia; Li, Liwu

    2014-08-01

    Innate monocytes and macrophages can be dynamically programmed into distinct states depending upon the strength of external stimuli. Innate programming may bear significant relevance to the pathogenesis and resolution of human inflammatory diseases. However, systems analyses with regard to the dynamic programming of innate leukocytes are lacking. In this study, we focused on the dynamic responses of human promonocytic THP-1 cells to lipopolysaccharide (LPS). We observed that varying dosages of LPS differentially modulate the expression of selected pro- and anti- inflammatory mediators such as IL-6 and IL-33. Super-low dosages of LPS preferentially induced the pro-inflammatory mediator IL-6, while higher dosages of LPS induced both IL-6 and IL-33. Mechanistically, we demonstrated that super-low and high doses of LPS cause differential activation of GSK3 and Akt, as well as the transcription factors FoxO1 and CREB. Inhibition of GSK3 enabled THP-1 cells to express IL-33 when challenged with super-low dose LPS. On the other hand, activation of CREB with adenosine suppressed IL-6 expression. Taken together, our study reveals a dynamic modulation of monocytic cells in response to varying dosages of endotoxin, and may shed light on our understanding of the dynamic balance that controls pathogenesis and resolution of inflammatory diseases. PMID:24970893

  18. Beneficial Effects of Fractions of Nardostachys jatamansi on Lipopolysaccharide-Induced Inflammatory Response

    PubMed Central

    Heo, Kwang-Ho; Choi, Sun Bok; Jo, Il-Joo; Kim, Dong-Goo; Shin, Joon-Yeon; Seo, Seung-Hee; Park, Kyoung-Chel; Lee, Dong-Sung; Oh, Hyuncheol; Kim, Youn-Chul; Song, Ho-Joon; Shin, Byung-Cheul

    2014-01-01

    It has been previously shown that Nardostachys jatamansi (NJ) exhibits anti-inflammatory properties against lipopolysaccharide (LPS) challenges. However, the potency of NJ constituents against LPS-induced inflammatory responses has not been examined. In this present study, we determined which NJ extract fractions exhibit inhibitory effects against LPS-induced inflammatory responses. Among the NJ fractions, NJ-1, NJ-3, NJ-4, and NJ-6 inhibited LPS-induced production of NO. The NJ-3, NJ-4, and NJ-6 fractions also inhibited the production of cytokines, such as IL-1?, IL-6, and TNF-?. However, NJ-1, NJ-3, NJ-4, and NJ-6 showed differential inhibitory mechanisms against LPS-induced inflammatory responses. NJ-1, NJ-3, and NJ-4 inhibited LPS-induced activation of c-jun NH2-terminal kinase (JNK) and p38 but did not affect activation of extracellular signal-regulated kinase (ERK) or NF-?B. On the other hand, NJ-6 inhibited activation of MAPKs and NF-?B. In addition, in vivo experiments revealed that administration of NJ-1, NJ-3, NJ-4, and NJ-6 reduced LPS-induced endotoxin shock, with NJ-6 especially showing a marked protective effect. Taken together, these results provide the evidence for the potential of selective NJ fractions against LPS-induced inflammation. Thus, it will be advantageous to further isolate and determine single effective compounds from these potent fractions. PMID:24795771

  19. Beneficial Effects of Fractions of Nardostachys jatamansi on Lipopolysaccharide-Induced Inflammatory Response.

    PubMed

    Bae, Gi-Sang; Heo, Kwang-Ho; Choi, Sun Bok; Jo, Il-Joo; Kim, Dong-Goo; Shin, Joon-Yeon; Seo, Seung-Hee; Park, Kyoung-Chel; Lee, Dong-Sung; Oh, Hyuncheol; Kim, Youn-Chul; Song, Ho-Joon; Shin, Byung-Cheul; Park, Sung-Joo

    2014-01-01

    It has been previously shown that Nardostachys jatamansi (NJ) exhibits anti-inflammatory properties against lipopolysaccharide (LPS) challenges. However, the potency of NJ constituents against LPS-induced inflammatory responses has not been examined. In this present study, we determined which NJ extract fractions exhibit inhibitory effects against LPS-induced inflammatory responses. Among the NJ fractions, NJ-1, NJ-3, NJ-4, and NJ-6 inhibited LPS-induced production of NO. The NJ-3, NJ-4, and NJ-6 fractions also inhibited the production of cytokines, such as IL-1 ? , IL-6, and TNF- ? . However, NJ-1, NJ-3, NJ-4, and NJ-6 showed differential inhibitory mechanisms against LPS-induced inflammatory responses. NJ-1, NJ-3, and NJ-4 inhibited LPS-induced activation of c-jun NH2-terminal kinase (JNK) and p38 but did not affect activation of extracellular signal-regulated kinase (ERK) or NF- ? B. On the other hand, NJ-6 inhibited activation of MAPKs and NF- ? B. In addition, in vivo experiments revealed that administration of NJ-1, NJ-3, NJ-4, and NJ-6 reduced LPS-induced endotoxin shock, with NJ-6 especially showing a marked protective effect. Taken together, these results provide the evidence for the potential of selective NJ fractions against LPS-induced inflammation. Thus, it will be advantageous to further isolate and determine single effective compounds from these potent fractions. PMID:24795771

  20. Pseudomonas aeruginosa PAO-1 Lipopolysaccharide-Diphtheria Toxoid Conjugate Vaccine: Preparation, Characterization and Immunogenicity

    PubMed Central

    Najafzadeh, Faezeh; Shapouri, Reza; Rahnema, Mehdi; Rokhsartalab Azar, Shadi; Kianmehr, Anvarsadat

    2015-01-01

    Background: Treatment of Pseudomonas aeruginosa PAO-1 infections through immunological means has been proved to be efficient and protective. Objectives: The purpose of this study was to produce a conjugate vaccine composed of detoxified lipopolysaccharide (D-LPS) P. aeruginosa and diphtheria toxoid (DT). Materials and Methods: Firstly, LPS was purified and characterized from P. aeruginosa PAO1 and then detoxified. D-LPS was covalently coupled to DT as a carrier protein via amidation method with adipic acid dihydrazide (ADH) as a spacer molecule and 1-ethyl-3- (3-dimethylaminopropyl) carbodiimide (EDAC) as a linker. The molar ratio of LPS to DT in the prepared conjugate was 3:1. The immunogenicity of D-LPS-DT conjugate vaccine in mice model was evaluated as well. Results: The conjugate was devoid of endotoxin activity and 0.125 U/mL of D-LPS was acceptable for immunization. D-LPS-DT conjugate was nonpyrogenic for rabbits and nontoxic for mice. Mice immunization with D-LPS-DT conjugate vaccine elicited the fourfold higher IgG antibody compared to D-LPS. Anti-LPS IgG antibody was predominantly IgG1 subclass and then IgG3, IgG2a and IgG2b, respectively. Conclusions: Vaccine based on the conjugation of P. aeruginosa PAO-1 LPS with DT increased anti-LPS antibodies and had a significant potential to protect against Pseudomonas infections. PMID:26301059

  1. Lipopolysaccharide induced apoptosis of rat pancreatic acinar cells.

    PubMed Central

    Laine, V J; Nyman, K M; Peuravuori, H J; Henriksen, K; Parvinen, M; Nevalainen, T J

    1996-01-01

    BACKGROUND--Bacterial lipopolysaccharide (LPS) has been proposed to participate in the pathogenesis of pancreatic inflammatory disease. AIMS--This study investigated the role of endotoxaemia in the pathogenesis of pancreatic acinar cell injury. METHODS--Sixty eight male Spraque-Dawley rats were used in the study. Escherichia coli LPS (5 mg/kg) was injected into the peritoneal cavity of the rats. The concentration of pancreatic phospholipase A2 (PLA2) in plasma was measured and pancreatic tissue examined by histology, in situ detection of free DNA 3'-ends, and electrophoretic DNA analysis. RESULTS--The concentration of pancreatic PLA2 increased in plasma and the catalytic activity of PLA2 increased in pancreatic tissue after an LPS injection. Apoptosis in pancreatic acinar cells and fragmentation of DNA typical of apoptosis in pancreatic tissue was seen 24 hours after an LPS injection. Pancreatic acinar atrophy was seen 72 hours after the LPS injection. CONCLUSIONS--These data show that LPS causes release of pancreatic PLA2 into blood plasma, activation of PLA2 in pancreatic tissue, and apoptosis of acinar cells. Images Figure 3 Figure 4 Figure 5 PMID:8707123

  2. INTERLEUKIN-1B AND TUMOR NECROSIS FACTOR-A MEDIATION OF ENDOTOXIN ACTION: EFFECT ON GROWTH HORMONE

    Technology Transfer Automated Retrieval System (TEKTRAN)

    In humans and sheep, administration of endotoxin results in increased concentrations of growth hormone (GH). Experiments were designed to determine the mechanism by which endotoxin increases concentrations of GH. To determine if cytokines mediated the effect of endotoxin on GH, sheep were challeng...

  3. Enhancement of systemic and sputum granulocyte response to inhaled endotoxin in people with the GSTM1 null genotype

    EPA Science Inventory

    To determine if the GSTM1 null genotype is a risk factor for increased inflammatory response to inhaled endotoxin. Methods 35 volunteers who had undergone inhalation challenge with a 20 000 endotoxin unit dose of Clinical Center Reference Endotoxin (CCRE) were genotyped for the G...

  4. Marine aerosol as a possible source for endotoxins in coastal areas.

    PubMed

    Lang-Yona, Naama; Lehahn, Yoav; Herut, Barak; Burshtein, Noa; Rudich, Yinon

    2014-11-15

    Marine aerosols, that are very common in the highly populated coastal cities and communities, may contain biological constituents. Some of this biological fraction of marine aerosols, such as cyanobacteria and plankton debris, may influence human health by inflammation and allergic reactions when inhaled. In this study we identify and compare sources for endotoxins sampled on filters in an on-shore and more-inland site. Filter analysis included endotoxin content, total bacteria, gram-negative bacteria and cyanobacteria genome concentrations as well as ion content in order to identify possible sources for the endotoxins. Satellite images of chlorophyll-a levels and back trajectory analysis were used to further study the cyanobacteria blooms in the sea, close to the trajectory of the sampled air. The highest endotoxin concentrations found in the shoreline site were during winter (3.23±0.17 EU/m(3)), together with the highest cyanobacteria genome (1065.5 genome/m(3)). The elevated endotoxin concentrations were significantly correlated with cyanobacterial levels scaled to the presence of marine aerosol (r=0.90), as well as to chlorophyll-a (r=0.96). Filters sampled further inland showed lower and non-significant correlation between endotoxin and cyanobacteria (r=0.70, P value=0.19), suggesting decrease in marine-originated endotoxin, with possible contributions from other sources of gram-negative non-cyanobacteria. We conclude that marine cyanobacteria may be a dominant contributor to elevated endotoxin levels in coastal areas. PMID:25201818

  5. MICROWAVE RADIATION (2450 MHZ) ALTERS THE ENDOTOXIN-INDUCED HYPOTHERMIC RESPONSE OF RATS

    EPA Science Inventory

    The parental administration of bacterial endotoxin to rats causes a hypothermia that is maximal after approximately 90 minutes. When endotoxin-injected rats were held in a controlled environment at 22C and 50% relative humidity and exposed for 90 minutes to microwaves (2450 MHz, ...

  6. Exposure to wood dust and endotoxin in small-scale wood industries in Tanzania.

    PubMed

    Rongo, Larama Mb; Msamanga, Gernard I; Burstyn, Igor; Barten, Françoise; Dolmans, Wil Mv; Heederik, Dick

    2004-11-01

    Workers in small-scale wood industries (SSWI) have increased risks of developing asthma and other respiratory diseases. Wood dust and microbial agents have both been suggested to play a role, but few studies have measured endotoxin exposure in SSWI in Africa. We assessed inhalable dust levels in 281 samples from 115 workers and bacterial endotoxins levels in 157 samples from 136 workers from SSWI in Dar es Salaam, Tanzania. The overall geometric mean of personal exposure was 3.3 mg/m(3); geometric standard deviation (GSD) 2.5; range 0.45-67.0 mg/m(3)) and 91 EU/m(3) (GSD 3.7; range 9-4914.8 EU/m(3)) for wood dust and endotoxins, respectively. Dust and endotoxin levels were weakly correlated (r = 0.44, n = 157, P < 0.0001). Between- and within-worker variances and percentages explained by the differences among job titles and seasons were 0.31 (9%) and 0.35 (30%), respectively, for wood dust exposure, and 0.35 (0%) and 0.35 (38%) for endotoxin exposure. Higher dust and endotoxin exposure levels were observed in the dry compared to the wet season, after correcting for differences in exposure between jobs. Carving and manual cleaning were associated with the highest dust exposures. Sewing seat covers and manual cleaning were associated with the highest endotoxin exposures. Dust and endotoxin exposure levels in SSWI are high and appropriate control measures are necessary. PMID:15114366

  7. Electrochemical endotoxin sensors based on TLR4/MD-2 complexes immobilized on gold electrodes.

    PubMed

    Yeo, Tae Yun; Choi, Ji Suk; Lee, Byung Kook; Kim, Beob Soo; Yoon, Hwa In; Lee, Hyeong Yun; Cho, Yong Woo

    2011-10-15

    Even low concentrations of endotoxins can be life-threatening. As such, continuous effort has been directed toward the development of sensitive and specific endotoxin detection systems. In this paper, we report the design and fabrication of a new electrochemical endotoxin sensor based on a human recombinant toll-like receptor 4 (rhTLR4) and myeloid differentiation-2 (MD-2) complex. The rhTLR4/MD-2 complex, which specifically binds to endotoxin, was immobilized on gold electrodes through a self-assembled monolayer (SAM) technique involving the use of dithiobis(succinimidyl undecanoate) (DSU). The surface topography of the electrodes at each fabrication stage was characterized with a nanosurface profiler and atomic force microscope (AFM). The electrochemical signals generated from interactions between the rhTLR4/MD-2 complex and the endotoxin were characterized by cyclic voltammetry (CV) and differential pulse voltammetry (DPV). A linear relationship between the peak current and endotoxin concentration was obtained in the range of 0.0005 to 5 EU/mL with a correlation coefficient (R(2)) of 0.978. The estimated limit of detection (LOD) was fairly low, 0.0002 EU/mL. The rhTLR4/MD-2 based sensors exhibited no current responses to dipalmitoylphosphatidylcholine (DPPC) bearing two lipid chains, which is structurally similar to endotoxin, indicating the high specificity of the sensors to endotoxin. PMID:21816600

  8. Personal Exposure to Dust and Endotoxin in Robusta and Arabica Coffee Processing Factories in Tanzania

    PubMed Central

    Sakwari, Gloria

    2013-01-01

    Introduction: Endotoxin exposure associated with organic dust exposure has been studied in several industries. Coffee cherries that are dried directly after harvest may differ in dust and endotoxin emissions to those that are peeled and washed before drying. The aim of this study was to measure personal total dust and endotoxin levels and to evaluate their determinants of exposure in coffee processing factories. Methods: Using Sidekick Casella pumps at a flow rate of 2l/min, total dust levels were measured in the workers’ breathing zone throughout the shift. Endotoxin was analyzed using the kinetic chromogenic Limulus amebocyte lysate assay. Separate linear mixed-effects models were used to evaluate exposure determinants for dust and endotoxin. Results: Total dust and endotoxin exposure were significantly higher in Robusta than in Arabica coffee factories (geometric mean 3.41mg/m3 and 10 800 EU/m3 versus 2.10mg/m3 and 1400 EU/m3, respectively). Dry pre-processed coffee and differences in work tasks explained 30% of the total variance for total dust and 71% of the variance for endotoxin exposure. High exposure in Robusta processing is associated with the dry pre-processing method used after harvest. Conclusions: Dust and endotoxin exposure is high, in particular when processing dry pre-processed coffee. Minimization of dust emissions and use of efficient dust exhaust systems are important to prevent the development of respiratory system impairment in workers. PMID:23028014

  9. Relationship between chicken cellular immunity and endotoxin levels in dust from chicken housing environments

    PubMed Central

    Roque, Katharine; Shin, Kyung-Min; Jo, Ji-Hoon; Kim, Hyoung-Ah

    2015-01-01

    Hazardous biochemical agents in animal husbandry indoor environments are known to promote the occurrence of various illnesses among workers and animals. The relationship between endotoxin levels in dust collected from chicken farms and various immunological markers was investigated. Peripheral blood was obtained from 20 broiler chickens and 20 laying hens from four different chicken farms in Korea. Concentrations of total or respirable dust in the inside the chicken farm buildings were measured using a polyvinyl chloride membrane filter and mini volume sampler. Endotoxin levels in the dust were determined by the Limulus Amebocyte Lysate Kinetic method. Interferon-? production by peripheral blood mononuclear cells stimulated with concanavalin A was significantly lower in broilers or layers from the farms with higher endotoxin concentrations than the chickens from the farms with lower endotoxin levels. An opposite pattern was observed for plasma cortisol concentrations with higher cortisol levels found in chickens from the farms with higher endotoxin levels. When peripheral lymphocytes were examined, the percentage of CD3-Ia+ B cells was lower in layers from farms with higher endotoxin levels than those from locations with lower endotoxin levels. Overall, these results suggest a probable negative association between dust endotoxin levels and cell-mediated immunity in chickens. PMID:25549222

  10. Documentation of the endotoxins present in the ambient air of cotton fiber textile mills in Québec.

    PubMed

    Marchand, Geneviève; Lalonde, Michèle; Beaudet, Yves; Boivin, Gilles; Villeneuve, Sylvie; Pépin, Carole

    2007-08-01

    Cotton workers are recognized as being at risk of developing occupational lung diseases. Some researchers have identified endotoxins as being a potential etiologic agent for some of the respiratory problems. This study wants to document the concentration of endotoxins found in the ambient air of textile mills where cotton fibers are handled and to identify the processing steps where the highest endotoxins concentrations in the air were found and the one where the relative limit values (RLVs) are exceeded. The 4 mills studied process cotton fibers. All the air samples were analyzed using the chromogenic Limulus Amoebocytes lysate LAL method using a kinetic detection principle based on the IRSST's standard method. In this study, a large variability in the concentrations of endotoxins in the air was observed, depending on the mill, the processing step, and the time. Despite these variations, some processes can be identified as being major generators of endotoxins in the ambient air of the mills. The highest concentrations were measured in the weaving and drawing processes and reached 10,000 EU m(-3) of air. The opening, cleaning, carding, spinning and drawing processes are the other major endotoxins generating processes with concentrations from 24 to 8,700 EU m(-3) of air. The endotoxins concentrations exceeded the RLVs for 55% of the workstations in this project. This study demonstrated that endotoxins levels in the cotton industry are high and appropriate control measures are needed. PMID:17671669

  11. Structure and genetics of biosynthesis of the glycosyl phosphate-containing O-polysaccharide of Escherichia coli O160.

    PubMed

    Perepelov, Andrei V; Guo, Xi; Senchenkova, Sof'ya N; Shashkov, Alexander S; Knirel, Yuriy A

    2015-11-19

    On mild acid degradation of the lipopolysaccharide of Escherichia coli O160, the O-polysaccharide was cleaved by acid-labile glycosyl phosphate linkages in the main chain. The resultant oligosaccharide and the alkali-treated lipopolysaccharide were studied by sugar analysis along with (1)H and (13)C NMR spectroscopies, and the following structure of the branched pentasaccharide repeating unit of the O-polysaccharide was established: The O-antigen gene cluster of E.?coli O160 was found to be consistent with the O-polysaccharide structure established. PMID:26451883

  12. Lipopolysaccharide aggregates in native agarose gels detected by reversible negative staining with imidazole and zinc salts.

    PubMed

    Rodríguez, Caridad; Hardy, Eugenio

    2015-09-15

    We investigated the use of imidazole and zinc salts for the detection of lipopolysaccharide (LPS) aggregates separated by native agarose gel electrophoresis (NAGE). As a result, a new staining procedure was established by which as little as 1.5 ?g of Escherichia coli O55:B5 LPS aggregates was detected by means of inducing a clear, transparent pattern, contrasted against an opaque background. E. coli O55:B5 LPS preparations treated with nucleases and proteinase K proved that the reverse-stained LPS pattern is not related to any potential artifacts caused by unrelated biomolecules (e.g., nucleic acids, proteins). After this, we showed that the procedure is applicable to two-dimensional LPS separation using NAGE/SDS-PAGE, while at the same time confirming that real polydisperse LPS aggregates are represented by the stained profile. Also, we demonstrated the general applicability of this stain to the detection of different NAGE-separated LPS aggregates (e.g., from E. coli 026:B6, E. coli 0111:B4, Salmonella minnesota Re595). Finally, using lysozyme as a model protein, we found that imidazole-zinc may be combined with Coomassie brilliant blue R-250 into a double-staining process to enable the use of NAGE for investigating the interaction of cationic proteins and LPS aggregates and protein or LPS concentration effects on protein-LPS binding. PMID:26095395

  13. Immunomodulation in Sepsis: The Role of Endotoxin Removal by Polymyxin B-Immobilized Cartridge

    PubMed Central

    Ferrer, Ricard; Artigas, Antonio

    2013-01-01

    Severe sepsis results in high morbidity and mortality. Immunomodulation strategies could be an adjunctive therapy to treat sepsis. Endotoxin is a component of gram-negative bacteria and plays an important role in the pathogenesis of septic shock when it is recognized by immune cells. Removal of endotoxin could be an effective adjunctive approach to the management of sepsis. Devices to adsorb endotoxin or inflammatory cytokines have been designed as a strategy to treat severe sepsis, especially sepsis caused by gram-negative bacteria. Polymyxin B-immobilized cartridge has been successfully used to treat patients with sepsis of abdominal origin. Although this cartridge was conceived to adsorb endotoxin, several other immunological mechanisms have been elucidated, and this device has also yielded promising results in patients with nonseptic respiratory failure. In this paper, we summarize the immune modulation actions of Polymyxin B-immobilized cartridge to explore its potential usefulness beyond endotoxin elimination. PMID:24249974

  14. Insoluble glycogen, a metabolizable internal adsorbent, decreases the lethality of endotoxin shock in rats

    PubMed Central

    Bot, G.; Gergely, P.; Bertók, L.; Csongor, J.; Sápy, P.; Szappanos, M.; Nemes, J.; Duda, E.; Szegedi, G.

    1997-01-01

    Insoluble glycogen is an enzymatically modified form of naturally occurring soluble glycogen with a great adsorbing capacity. It can be metabolized by phagocytes to glucose. In this study we used insoluble glycogen intravenously in the experimental endotoxin shock of rats. Wistar male rats were sensitized to endotoxin by Pb acetate. The survival of rats were compared in groups of animals endotoxin shock treated and non-treated with insoluble glycogen. Furthermore, we have determined in vitro the binding capacity of insoluble glycogen for endotoxin, tumour necrosis factor alpha, interleukin-1 and secretable phospholipase A2. Use of 10 mg/kg dose of insoluble glycogen could completely prevent the lethality of shock induced by LD50 quantity of endotoxin in rats. All animals treated survived. Insoluble glycogen is a form of ‘metabolizable internal adsorbents’. It can potentially be used for treatment of septic shock. PMID:18472865

  15. [Detection of endotoxin in plasma: specificity and value for development and prognosis of infection].

    PubMed

    Urbaschek, R; Becker, K P

    1993-04-01

    A number of problems may be involved in the detection of endotoxin in plasma of patients using LAL (Limulus amebocyte lysate). When collecting blood or processing samples, contamination with endotoxin or its adsorption to material must be avoided. In our laboratory a kinetic LAL microtiter assay was developed that takes into account plasma-related interferences with the LAL endotoxin reaction by performing an internal standardization in each sample. Negative results do not absolutely exclude the involvement of endotoxins in the underlying disease. High levels of endotoxins do not necessarily reflect the severeness of the clinical status of the patient. Due to nonendotoxin-specific reactions with some complete lysates, false-positive levels may result, e.g., following immunoglobulin therapy. In spite of these limitations, the LAL test remains a valuable tool in the evaluation of gram-negative infections. PMID:8499746

  16. The significance of endotoxin release in experimental and clinical sepsis in surgical patients--evidence for antibiotic-induced endotoxin release?

    PubMed

    Holzheimer, R G

    1998-01-01

    Sepsis and peritonitis remain a serious challenge for surgical patients, despite improvement in surgical therapy and intensive care and the introduction of new powerful antibiotics. Recent in vitro studies revealed the potential of certain antibiotics, e.g. penicillin-binding protein (PBP) 3-specific antibiotics, to cause antibiotic-induced endotoxin release. Other types of antibiotics, e.g., PBP 2-specific antibiotics, were associated with no or less endotoxin release. Further in vitro experiments and investigations in animals support the hypothesis of antibiotic-induced endotoxin release, but there is little clinical evidence. The clinical significance of endotoxin is subject of open dispute with many pro's and contra's. Endotoxin, although an important trigger, may not be the only factor to induce cytokine release, e.g., peptidoglycans were able to stimulate cells to release cytokines. Gram-positive pathogens have gained more importance in clinical sepsis and may not be sufficiently reflected in current clinical studies. The hypothesis that neutralization of endotoxin and pro-inflammatory cytokines is beneficial in sepsis was seriously challenged by the results of recent clinical and experimental studies. The better understanding of mechanisms in endotoxin-induced cell activation and cell, cell-receptor and soluble receptor interactions led to new treatment options. Recent reports on the complex pathogenesis of peritonitis and the detection of pathogen-related factors with intraperitoneal immune response may have implications on clinical studies investigating the potential of new compounds and the effect of antibiotics on endotoxin release. However, only few reports are available on the clinical significance of antibiotic-induced endotoxin release, and association of endotoxin release with pathogens, mortality or alteration of physiological parameters were not observed. With regard to the particulars of these studies, e.g., a small study population or low mortality rate, mortality may not be an ideal outcome parameter for these studies. There is clinical evidence for antibiotic-induced endotoxin release. However, the need for well-designed and performed studies using newly developed monitoring devices in intensive care therapy is obvious. PMID:9561376

  17. E. Coli and Pregnancy

    MedlinePLUS

    ... care provider. What is E. coli? E. coli (Escherichia coli) is a bacterium that lives in your colon ( ... 10):1411-1413. Jones B, et al. 2004. Escherichia coli: a growing problem in early onset neonatal sepsis. ...

  18. E. Coli Infection

    MedlinePLUS

    ... is E. coli? E. coli is short for Escherichia coli -- bacteria (germs) that cause severe cramps and diarrhea. E. ... and especially in people who have another illness. E. coli infection is more common during the summer months and ...

  19. Alcohol, intestinal bacterial growth, intestinal permeability to endotoxin, and medical consequences: summary of a symposium.

    PubMed

    Purohit, Vishnudutt; Bode, J Christian; Bode, Christiane; Brenner, David A; Choudhry, Mashkoor A; Hamilton, Frank; Kang, Y James; Keshavarzian, Ali; Rao, Radhakrishna; Sartor, R Balfour; Swanson, Christine; Turner, Jerrold R

    2008-08-01

    This report is a summary of the symposium on Alcohol, Intestinal Bacterial Growth, Intestinal Permeability to Endotoxin, and Medical Consequences, organized by National Institute on Alcohol Abuse and Alcoholism, Office of Dietary Supplements, and National Institute of Diabetes and Digestive and Kidney Diseases of National Institutes of Health in Rockville, Maryland, October 11, 2006. Alcohol exposure can promote the growth of Gram-negative bacteria in the intestine, which may result in accumulation of endotoxin. In addition, alcohol metabolism by Gram-negative bacteria and intestinal epithelial cells can result in accumulation of acetaldehyde, which in turn can increase intestinal permeability to endotoxin by increasing tyrosine phosphorylation of tight junction and adherens junction proteins. Alcohol-induced generation of nitric oxide may also contribute to increased permeability to endotoxin by reacting with tubulin, which may cause damage to microtubule cytoskeleton and subsequent disruption of intestinal barrier function. Increased intestinal permeability can lead to increased transfer of endotoxin from the intestine to the liver and general circulation where endotoxin may trigger inflammatory changes in the liver and other organs. Alcohol may also increase intestinal permeability to peptidoglycan, which can initiate inflammatory response in liver and other organs. In addition, acute alcohol exposure may potentiate the effect of burn injury on intestinal bacterial growth and permeability. Decreasing the number of Gram-negative bacteria in the intestine can result in decreased production of endotoxin as well as acetaldehyde which is expected to decrease intestinal permeability to endotoxin. In addition, intestinal permeability may be preserved by administering epidermal growth factor, l-glutamine, oats supplementation, or zinc, thereby preventing the transfer of endotoxin to the general circulation. Thus reducing the number of intestinal Gram-negative bacteria and preserving intestinal permeability to endotoxin may attenuate alcoholic liver and other organ injuries. PMID:18504085

  20. The ability of endotoxin adsorption during a longer duration of direct hemoperfusion with a polymyxin B-immobilized fiber column in patients with septic shock.

    PubMed

    Shimizu, Tomoharu; Obata, Toru; Sonoda, Hiromichi; Akabori, Hiroya; Tabata, Takahisa; Eguchi, Yutaka; Endo, Yoshihiro; Tani, Tohru

    2013-12-01

    The patients' hemodynamic conditions of septic shock due to intra-abdominal infection were improved by the longer duration of direct hemoperfusion with a polymyxin B-immobilized fiber column (PMX), reducing plasma endotoxins measured by the novel endotoxin detection method, named endotoxin scattering photometry (ESP) method; however, turbidimetric method could not detect endotoxins. We also observed the reduction in the endotoxin after passing through column by ESP method even after the longer duration of PMX. ESP method may more sensitively detect endotoxins than the ordinary turbidimetric method. Moreover, we demonstrated the ability of endotoxin adsorption in spite of the longer duration of PMX. PMID:23683501

  1. Detection of endotoxin using a photonic crystal nanolaser

    SciTech Connect

    Takahashi, Daichi; Hachuda, Shoji; Watanabe, Takumi; Nishijima, Yoshiaki; Baba, Toshihiko

    2015-03-30

    Fast and reliable detection of endotoxin (ET) in medical equipment and pharmaceutical products is an essential precursor to clinical treatment. In this study, we demonstrate the use of shifts in wavelength of photonic crystal nanolasers for sensing the Limulus amebocyte lysate reaction, which is a standard method for detecting ET. From working curves of wavelength shift vs ET concentration, whose correlation factors were as high as 98%, we detected a required concentration of 0.001 EU/ml within 33?min and detected a low concentration of 0.0001?EU/ml.

  2. Modulation of granulocyte functions by bacterial exotoxin and endotoxins.

    PubMed Central

    Bremm, K D; König, W; Thelestam, M; Alouf, J E

    1987-01-01

    The modulation of granulocyte functions by bacterial exotoxins (Streptolysin O, alveolysin, theta toxin) and endotoxins from salmonella and lipid A is described here. Incubation of polymorphonuclear granulocytes with thiol-activated toxins resulted in an increased leukotriene generation. Toxin-pretreated PMNs revealed an increased omega oxidation of LTB4, which may explain why toxin-stimulated cells release more LTC4 than LTB4. Furthermore, toxin-pretreated PMNs showed a decreased leukotriene generation on subsequent stimulation with the Ca-ionophore A 23187 or opsonized zymosan. PMID:2889665

  3. Biophysical Mechanisms of the Neutralization of Endotoxins by Lipopolyamines

    E-print Network

    Sil, Diptesh; Heinbockel, Lena; Kaconis, Yani; Rö ssle, Manfred; Garidel, Thomas; David, Sunil A.; Brandenburg, Klaus

    2013-09-30

    stream_size 49736 stream_content_type text/plain stream_name Sil_et_al_2013.pdf.txt stream_source_info Sil_et_al_2013.pdf.txt Content-Encoding UTF-8 Content-Type text/plain; charset=UTF-8 Send Orders of Reprints... at reprints@benthamscience.net 82 The Open Biochemistry Journal, 2013, 7, 82-93 1874-091X/13 2013 Bentham Open Open Access Biophysical Mechanisms of the Neutralization of Endotoxins by Lipopoly- amines Diptesh Sil1, Lena Heinbockel2, Yani Kaconis2...

  4. Inter- and intrasubject variability of the inflammatory response to segmental endotoxin challenge in healthy volunteers.

    PubMed

    Holz, O; Tan, L; Schaumann, F; Müller, M; Scholl, D; Hidi, R; McLeod, A; Krug, N; Hohlfeld, J M

    2015-12-01

    Segmental endotoxin challenge with lipopolysaccharide (LPS) can be used as a pharmacodynamic model to safely induce a transient airway inflammation in the peripheral lung of healthy subjects and to test the anti-inflammatory efficacy of investigational new drugs. In contrast to whole lung LPS challenge only a fraction of the dose is required that can be precisely administered to a specific lung region and a vehicle challenged segment as an intra-subject control can be included. The aim of this study was to assess the intra- and inter-individual variability of the response to segmental LPS challenge for the appropriate design and power calculation of future clinical trials. Two cohorts with 10 subjects each underwent two segmental LPS challenges within five weeks. The inflammatory response was evaluated in bronchoalveolar lavage (BAL) fluid at 6 (cohort 1) and 24 h (cohort 2) both in the LPS and in a vehicle challenged segment, as well as in plasma for up to 26 h post LPS challenge. While the cytokine response was more pronounced at 6 h, the influx of neutrophils and monocytes dominated at 24 h; e.g. neutrophils increased from a median (inter-quartile range, IQR) of 0.14 (0.16) and 0.09 (0.08)x10(4) cells/mL BAL fluid at baseline to 10.2 (17.1) and 19.3 (15.9)x10(4) cells/mL 24 h after the two separate challenges. The within-subject variability was higher than the between-subject variability for most of the markers. However, sample size estimations based on the variability of outcome variables found lower or equal numbers with cross-over designs compared to parallel group designs for cellular markers at 24 h and cytokine variables at 6 h. The segmental LPS challenge model was safe. Future study designs have to balance between burden to the study subjects (4 versus 2 bronchoscopies), variability (within-versus between-subject), and the desired outcome variable (cells versus chemo/cytokine). PMID:26545873

  5. Topical administration of diminazene aceturate decreases inflammation in endotoxin-induced uveitis

    PubMed Central

    Zheng, Changwei; Lei, Chunyan; Chen, Zihe; Zheng, Shijie; Yang, Hongxia; Qiu, Yiguo

    2015-01-01

    Purpose Our previous study demonstrated that an intraperitoneal injection of Diminazene Aceturate (DIZE) attenuated uveitis by activating ocular angiotensin-converting enzyme 2 (ACE2). Here, we investigated the anti-inflammatory effects on the ocular anterior segment of a topical administration of a DIZE solution and explored the downstream target molecules involved in the anti-inflammatory mechanism after ACE2 activation. Methods Endotoxin-induced uveitis (EIU) in rats was induced by a subcutaneous injection of lipopolysaccharides (LPS, 200 ?g) in 0.1 ml of sterile saline. DIZE (0.025, 0.05, or 0.1%) and dexamethasone (0.1%) solutions were applied topically (10 ?l eyedrops) to both eyes 6X every two hours before and after LPS injection. The inflammation of the ocular anterior segment was observed and the clinical scores were evaluated 24 h after LPS injection. The total protein concentration and levels of tumor necrosis factor-? (TNF-?) and interleukin-6 (IL-6) in the aqueous humor were determined. CD11b-positive cells adjacent to the iris ciliary body (ICB) were stained by immunohistochemistry. The mRNA levels of inflammatory cytokines and mediators, including IL-1?, TNF-?, COX-2, and iNOS or NF-?B subunit p65 in the ICB, were analyzed by real time RT–PCR. The protein expression of NF-?B p65 and the phosphorylated protein of p38 MAPK were detected by western blotting. Results A topical administration of DIZE decreased clinical scores and the total protein concentration, as well as TNF-? and IL-6 levels in the aqueous humor. Meanwhile, the mRNA levels of inflammatory cytokines and mediators, including IL-1?, TNF-?, COX-2, and iNOS in the ICB, were downregulated. DIZE reduced the recruitment of CD11b-positive cells adjacent to the ICB. Furthermore, DIZE downregulated the expressions of NF-?B subunit p65 at protein and mRNA levels and inhibited the phosphorylation of p38 MAPK protein in the ICB. Conclusions A topical administration of DIZE suppressed ocular inflammation in EIU and decreased the levels of inflammatory cytokines. DIZE attenuated the activation of NF-?B and p38 MAPK in EIU, which may be associated with ACE2-mediated anti-inflammatory effects. Our data provided further evidence that DIZE may represent a novel class of drug for the management of ocular inflammation. PMID:25883526

  6. Inhibition of LiCl-induced conditioning of anticipatory nausea in rats following immune system stimulation: comparing the immunogens lipopolysaccharide, muramyl dipeptide, and polyinosinic: polycytidylic acid.

    PubMed

    Cloutier, Caylen J; Rodowa, Melinda-Sue; Cross-Mellor, Shelley K; Chan, Melissa Y T; Kavaliers, Martin; Ossenkopp, Klaus-Peter

    2012-05-15

    The effects of the bacterial endotoxins, lipopolysaccharide (LPS) and muramyl dipeptide (MDP; Experiment 1), and the viral mimetic, polyinosinic: polycytidylic acid (poly I:C; Experiment 2), on the acquisition of "conditioned gaping" behavior in the rodent model of LiCl-induced anticipatory nausea were examined. Experimentally naïve adult male Long-Evans rats were injected (intraperitoneal, i.p.) with either 200 ?g/kg LPS, 1.6 mg/kg MDP, or 0.9% saline (Experiment 1), or 4.0 mg/kg poly I:C or 0.9% saline (Experiment 2), 90 min prior to treatment with 127 mg/kg LiCl or saline control and immediately placed into a distinctive context for 30 min (repeated over 4 conditioning days, spaced 72 h apart). On a drug-free test day (72 h following conditioning day 4), each animal was re-exposed to the context for 10 min, and orofacial and aversive behavioral responses were video recorded and analyzed. The results showed that pre-treatment with LPS, MDP (Experiment 1), or poly I:C (Experiment 2) prior to LiCl+context conditioning significantly impaired the establishment of conditioned gaping behavior, thus blocking the acquisition of anticipatory nausea. Results varied in regards to peripheral acute-phase response sickness behaviors, with significantly reduced weight loss in LPS-treated animals, less robust weight loss in poly I:C-treated animals, and no significant reductions in body weight in MDP-treated animals. The learning impairments observed in the current study suggest that endotoxin treatment with bacterial and viral endotoxin may have stronger central effects on learning and memory behavior, relative to peripheral effects on body weight and other sickness-related responses. PMID:22342813

  7. Escherichia Coli

    ERIC Educational Resources Information Center

    Goodsell, David S.

    2009-01-01

    Diverse biological data may be used to create illustrations of molecules in their cellular context. I describe the scientific results that support a recent textbook illustration of an "Escherichia coli cell". The image magnifies a portion of the bacterium at one million times, showing the location and form of individual macromolecules. Results…

  8. Damage of lipopolysaccharides in outer cell membrane and production of ROS-mediated stress within bacteria makes nano zinc oxide a bactericidal agent

    NASA Astrophysics Data System (ADS)

    Patra, Prasun; Roy, Shuvrodeb; Sarkar, Sampad; Mitra, Shouvik; Pradhan, Saheli; Debnath, Nitai; Goswami, Arunava

    2014-12-01

    Zinc oxide nanoparticle (ZNP) has been synthesized by microwave-assisted technique with the aid of a buffer solution. ZNP inhibited the growth of bacterial system Escherichia coli, even its multidrug-resistant counterpart as well. Systematic evaluation reveals that bioavailable crystalline ZNP damages the lipopolysaccharide layer from outer membrane (OM) of E. coli, subsequently damages the OM followed by inner membrane, enters within the cell and generates extensive reactive oxygen species-mediated damage. A series of biochemical, biophysical and molecular techniques have been used to reach the conclusion. We believe this work is expected to enlighten the detailed mode of action study in bacterial system.

  9. Low-grade endotoxemia contributes to chronic inflammation in hemodialysis patients: examination with a novel lipopolysaccharide detection method.

    PubMed

    Terawaki, Hiroyuki; Yokoyama, Keitaro; Yamada, Yukiko; Maruyama, Yukio; Iida, Rinako; Hanaoka, Kazushige; Yamamoto, Hiroyasu; Obata, Toru; Hosoya, Tatsuo

    2010-10-01

    Chronic inflammation has recently been proposed to play a major role in the development of cardiovascular disease and mortality among advanced chronic kidney disease (CKD) patients; however, why advanced CKD promotes chronic inflammation is still unclear. We hypothesized that a very low level of plasma endotoxin (lipopolysaccharide [LPS]) contributes to chronic inflammation in advanced CKD patients. We measured the plasma LPS levels using a novel LPS detection method (ESP method, a method for endotoxin detection using laser scattering photometry) concurrently with serum C-reactive protein (CRP) levels and various blood tests in 17 stable hemodialysis (HD) patients. As a result, the median LPS levels measured by the ESP method was 0.23 pg/mL (range, 0.01-3.89) (inflow, start of HD), 0.22 pg/mL (<0.01-9.97) (outflow, start of HD), 0.37 pg/mL (<0.01-7.42) (inflow, end of HD), and 1.07 pg/mL (<0.01-10.66) (dialysate), respectively; statistically significant differences were not detected between them. The predialysis median CRP level was 0.19 mg/dL (0.04-3.02). The logarithm of plasma LPS independently correlated with serum CRP (R = 0.595, P = 0.0103). In multiple (forward stepwise) regression analysis, in which CRP was determined to be the criterion variable, LPS (log), albumin, and the white blood cell count were adopted as independent explanatory variables (R = 0.401, -0.397 and 0.387, respectively). In conclusion, the present study revealed a significant relationship between LPS and CRP using the novel ESP method, and suggested that very low-grade endotoxemia is contributing to systemic inflammation in HD patients. PMID:21175546

  10. Airway oedema and obstruction in guinea pigs exposed to inhaled endotoxin.

    PubMed Central

    Gordon, T; Balmes, J; Fine, J; Sheppard, D

    1991-01-01

    Protein extravasation and airway conductance (SGaw) were examined in awake guinea pigs exposed to inhaled endotoxin or saline for three hours. A significant increase in protein extravasation (as estimated by the leakage of protein bound Evans blue dye) was seen in the conducting airways of endotoxin exposed animals compared with saline exposed animals. Mean dye extravasation was significantly increased by one to threefold in the mainstem and hilar bronchi of endotoxin exposed animals. These changes in extravasation were accompanied by decrements in pulmonary function and by an influx of polymorphonuclear leucocytes into the airway wall. The SGaw decreased significantly by 60-90 minutes into exposure to endotoxin and had decreased by 22% and 34% at the end of exposure in the low and high dose endotoxin groups, respectively. Similar findings were obtained in animals exposed to cotton dust. Contrary to studies suggesting that platelet activating factor (PAF) is involved in the systemic and peripheral lung effects of endotoxin, pretreatment with the PAF antagonist WEB2086 did not prevent the conducting airway injury produced by inhaled endotoxin. PMID:1911406

  11. Salivary ?-amylase response to endotoxin administration in humans.

    PubMed

    Grigoleit, Jan-Sebastian; Kullmann, Jennifer S; Oberbeck, Reiner; Schedlowski, Manfred; Engler, Harald

    2013-09-01

    Salivary ?-amylase (sAA) is a digestive enzyme that plays also an important role in mucosal immunity. Secretion of the sAA is largely under the control of the autonomic nervous system and increases in sAA activity have repeatedly been observed in response to various stressors. The present study aimed at investigating whether and to what extent sAA activity levels are affected during systemic inflammation. Fourteen healthy male volunteers received intravenous injections of either bacterial endotoxin or placebo at two different occasions in a randomized and double-blinded manner. sAA activity was monitored over a period of 6h together with inflammatory markers, plasma norepinephrine (NE) and salivary cortisol levels, vital parameters, and state anxiety. Endotoxin administration elicited a transient inflammatory response reflected by increases in body temperature, whole blood cell counts, and circulating levels of interleukin (IL)-6. The immune changes were accompanied by a transient increase in sAA activity, elevations in salivary cortisol and plasma NE concentrations, as well as increases in heart rate and state anxiety. Although sAA and plasma NE responses showed distinct time courses, a significant positive correlation over the total observation period was found. Whether the observed sAA response is driven by an increase in sympathetic activity or more generally reflects inflammation induced changes in sympathetic-parasympathetic balance remains to be elucidated. PMID:23394872

  12. Variation in the ovine cortisol response to systemic bacterial endotoxin challenge is predominantly determined by signalling within the hypothalamic-pituitary-adrenal axis

    SciTech Connect

    You Qiumei; Karrow, Niel A. Cao Honghe; Rodriguez, Alexander; Mallard, Bonnie A.; Boermans, Herman J.

    2008-07-01

    Bi-directional communication between the neuroendocrine and immune systems is designed, in part, to maintain or restore homeostasis during physiological stress. Exposure to endotoxin during Gram-negative bacterial infection for example, elicits the release of pro-inflammatory cytokines that activate the hypothalamic-pituitary-adrenal axis (HPAA). The secretion of adrenal glucocorticoids subsequently down regulates the host inflammatory response, minimizing potential tissue damage. Sequence and epigenetic variants in genes involved in regulating the neuroendocrine and immune systems are likely to contribute to individual differences in the HPAA response, and this may influence the host anti-inflammatory response to toxin exposure and susceptibility to inflammatory disease. In this study, high (HCR) and low (LCR) cortisol responders were selected from a normal population of 110 female sheep challenged iv with Escherichia coli endotoxin (400 ng/kg) to identify potential determinants that contribute to variation in the cortisol response phenotype. This phenotype was stable over several years in the HCR and LCR animals, and did not appear to be attributed to differences in expression of hepatic immune-related genes or systemic pro-inflammatory cytokine concentrations. Mechanistic studies using corticotrophin-releasing factor (0.5 {mu}g/kg body weight), arginine vasopressin (0.5 {mu}g/kg), and adrenocorticotropic hormone (0.5 {mu}g/kg) administered iv demonstrated that variation in this phenotype is largely determined by signalling within the HPAA. Future studies will use this ovine HCR/LCR model to investigate potential genetic and epigenetic variants that may contribute to variation in cortisol responsiveness to bacterial endotoxin.

  13. A cerebral nitrergic pathway modulates endotoxin-induced changes in gastric motility

    PubMed Central

    Quintana, Elsa; García-Zaragozá, Eugenia; Angeles Martínez-Cuesta, M; Calatayud, Sara; Esplugues, Juan V; Barrachina, María Dolores

    2001-01-01

    This study analyses the neural pathway involved in the modulation of gastric motor function by stress.Systemic administration of low doses of endotoxin (40??g?kg?1, i.v.) prevents the increase in gastric tone induced by 2-deoxy-D-glucose (200?mg?kg?1, i.v., 2-DG) in urethane-anaesthetized rats.Functional inhibition of afferent neurones by systemic administration of capsaicin (20+30+50?mg?kg?1, i.m.) in adult rats prevented the inhibitory effects of endotoxin.Pre-treatment with the nitric oxide synthase (NOS) inhibitor, NG-nitro-L-arginine methyl ester (L-NAME), both i.v. (10?mg?kg?1) and i.c. (200??g rat?1), prevented the inhibitory effects of endotoxin on gastric tone induced by 2-DG.Immunohistochemical studies show Fos expression in the dorsal vagal complex (DVC) of the brainstem of 2-DG-treated animals. Peripheral administration of endotoxin (40??g?kg?1, i.p.) increased the number of Fos-immunoreactive cells induced by 2-DG, both in the nucleus tractus solitarii (NTS) and in the dorsal motor nucleus (DMN) of the DVC. Pre-treatment with L-NAME prevented the increase in Fos expression induced by endotoxin in both nuclei.Endotoxin (40??g?kg?1, i.p.) increased Ca2+-dependent nitric oxide synthase (cNOS) activity in the brainstem. Addition of 7-nitroindazole (600??M, 7-NI) to the assay significantly inhibited the increase in cNOS activity caused by endotoxin. No change in NOS activity of any isoform was observed in the stomach of animals treated with endotoxin.The present study suggests that inhibition of gastric motor function by low doses of endotoxin involves activation of capsaicin-sensitive afferent neurones and neuronal NOS in the brainstem. PMID:11564650

  14. Effects of various starch feeding regimens on responses of dairy cows to intramammary lipopolysaccharide infusion.

    PubMed

    Gott, P N; Hogan, J S; Weiss, W P

    2015-03-01

    Endotoxin tolerance (ET) can develop in mammals that have been challenged repeatedly with sublethal amounts of lipopolysaccharide (LPS). Previous research has shown that subclinical ruminal acidosis can increase circulating concentrations of LPS. We investigated whether ET would develop in Holstein cows that were subjected to chronic subacute ruminal acidosis (SARA) or acute SARA followed by intramammary infusion of LPS. Twenty-four cows, both primiparous and multiparous, were assigned to 8 blocks of 3 cows. Cows within blocks were randomly assigned to 1 of 3 treatments: (1) control (diet DM was 24% starch and 35% NDF), (2) high starch (formulated to induce chronic milk fat depression with 29% starch and 32% NDF), and (3) acidosis (designed to cause acute bouts of milk fat depression by short-term feeding of a diet with 32% starch, some of which came from wheat grain, and 30% NDF). Cows on the control and high-starch treatments were fed their respective diets throughout the 24-d trial. The acidosis cows were fed the control diet during most of the experiment, except during two 2-d bouts (d 10 and 11 and 17 and 18 of the experiment) in which a high-starch diet was fed. Cows on the high-starch and acidosis treatments produced milk fat with an altered fatty acid profile indicative of SARA (e.g., increased concentrations of specific trans, and odd-, and branched-chain fatty acids), but only cows on the high-starch treatment had milk fat depression. Concentrations of serum amyloid A were elevated in cows on the acidosis treatment, but did not differ between control and high-starch cows. On d 20 of the experiment, all cows were given an intramammary infusion of 10 µg of LPS into 1 mammary quarter 3h after morning milking. Milk yield and DMI decreased the day of the infusion, but the response was not affected by dietary treatment. No systemic indicators of ET were observed among treatments, but evidence of an ET response at the local level of the mammary gland was observed. Cows fed the control diet had higher concentrations of serum amyloid A in milk 12 and 24h postinfusion than did cows fed the high-starch diet and higher concentrations than cows on the acidosis treatment at 12h postinfusion. Our data suggest cows that experienced varying degrees of SARA (based on altered milk fatty acid profile) and subsequent experimental endotoxin mastitis experienced a blunted inflammatory response at the level of the mammary gland, but not a systemic reduction in some inflammatory mediators. PMID:25547311

  15. Lipopolysaccharide Potentiates the Effect of Hepatocyte Growth Factor upon Replication

    E-print Network

    Ponder, Katherine P.

    Lipopolysaccharide Potentiates the Effect of Hepatocyte Growth Factor upon Replication in Lung in revised form January 10, 2001; published online April 13, 2001 Induction of replication may potentiate) increases the percentage of replicating hepatocytes to 18-fold that in normal rats, and lipopolysaccharide

  16. The molecular adsorption-type endotoxin detection system using immobilized ?-polylysine

    NASA Astrophysics Data System (ADS)

    Ooe, Katsutoshi; Tsuji, Akihito; Nishishita, Naoki; Hirano, Yoshiaki

    2007-12-01

    Hemodialysis for chronic renal failure is the most popular treatment method with artificial organs. However, hemodialysis patients must continue the treatment throughout their life, the results of long term extracorporeal dialysis, those patients develop the various complications and diseases, for example, dialysis amyloidosis etc. Dialysis amyloidosis is one of the refractory complications, and endotoxin is thought to be the most likely cause of it, recently. Endotoxin is one of the major cell wall components of gram-negative bacteria, and it has various biological activities. In addition, it is known that a mount of endotoxin exists in living environment, and medicine is often contaminated with endotoxin. When contaminated dialyzing fluids are used to hemodialysis, above-mentioned dialysis amyloidosis is developed. Therefore, it is important that the detection and removal of endotoxin from dialyzing fluids. Until now, the measurement methods using Limulus Amebosyte Lysate (LAL) reagent were carried out as the tests for the presence of endtoxin. However, these methods include several different varieties of measurement techniques. The following are examples of them, gelatinization method, turbidimetric assay method, colorimetric assay method and fluoroscopic method. However, these techniques needed 30-60 minutes for the measurement. From these facts, they are not able to use as a "real-time endotoxin detector". The detection of endotoxin has needed to carry out immediately, for that reason, a new detection method is desired. In this research, we focused attention to adsorption reaction between ?-polylysine and endotoxin. ?-polylysine has the structure of straight chain molecule composed by 25-30 residues made by lysine, and it is used as an antimicrobial agent, moreover, cellulose beads with immobilized ?-polylysine is used as the barrier filter for endotoxin removal. The endotoxin is adsorbed to immobilized ?-polylysine, as the result of this reaction, the mass incrementation is occurred, and the existence of endtoxin can be detected immediately, by using of Quartz Crystal Microbalance (QCM). In this report, the immobilization of ?-polylysine onto the Au and Si substrate and its adsorptive activity are described. We use X-ray Photoelectron Spectroscopy (XPS) to confirm the ?-polylysine immobilization, and the adsorptive activity of immobilized ?-polylysine is measured by AFM and QCM. This molecular adsorption type endotoxin sensor aims to the realization of "real-time endotoxin detection system".

  17. Histone Deacetylase Inhibitor Trichostatin A Ameliorated Endotoxin-Induced Neuroinflammation and Cognitive Dysfunction.

    PubMed

    Hsing, Chung-Hsi; Hung, Shih-Kai; Chen, Yeong-Chang; Wei, Tsui-Shan; Sun, Ding-Ping; Wang, Jhi-Joung; Yeh, Ching-Hua

    2015-01-01

    Excessive production of cytokines by microglia may cause cognitive dysfunction and long-lasting behavioral changes. Activating the peripheral innate immune system stimulates cytokine secretion in the central nervous system, which modulates cognitive function. Histone deacetylases (HDACs) modulate cytokine synthesis and release. Trichostatin A (TSA), an HDAC inhibitor, is documented to be anti-inflammatory and neuroprotective. We investigated whether TSA reduces lipopolysaccharide- (LPS-) induced neuroinflammation and cognitive dysfunction. ICR mice were first intraperitoneally (i.p.) injected with vehicle or TSA (0.3?mg/kg). One hour later, they were injected (i.p.) with saline or Escherichia coli LPS (1?mg/kg). We analyzed the food and water intake, body weight loss, and sucrose preference of the injected mice and then determined the microglia activation and inflammatory cytokine expression in the brains of LPS-treated mice and LPS-treated BV-2 microglial cells. In the TSA-pretreated mice, microglial activation was lower, anhedonia did not occur, and LPS-induced cognitive dysfunction (anorexia, weight loss, and social withdrawal) was attenuated. Moreover, mRNA expression of HDAC2, HDAC5, indoleamine 2,3-dioxygenase (IDO), TNF-?, MCP-1, and IL-1? in the brain of LPS-challenged mice and in the LPS-treated BV-2 microglial cells was lower. TSA diminished LPS-induced inflammatory responses in the mouse brain and modulated the cytokine-associated changes in cognitive function, which might be specifically related to reducing HDAC2 and HDAC5 expression. PMID:26273133

  18. Histone Deacetylase Inhibitor Trichostatin A Ameliorated Endotoxin-Induced Neuroinflammation and Cognitive Dysfunction

    PubMed Central

    Hsing, Chung-Hsi; Hung, Shih-Kai; Chen, Yeong-Chang; Wei, Tsui-Shan; Sun, Ding-Ping; Wang, Jhi-Joung; Yeh, Ching-Hua

    2015-01-01

    Excessive production of cytokines by microglia may cause cognitive dysfunction and long-lasting behavioral changes. Activating the peripheral innate immune system stimulates cytokine secretion in the central nervous system, which modulates cognitive function. Histone deacetylases (HDACs) modulate cytokine synthesis and release. Trichostatin A (TSA), an HDAC inhibitor, is documented to be anti-inflammatory and neuroprotective. We investigated whether TSA reduces lipopolysaccharide- (LPS-) induced neuroinflammation and cognitive dysfunction. ICR mice were first intraperitoneally (i.p.) injected with vehicle or TSA (0.3?mg/kg). One hour later, they were injected (i.p.) with saline or Escherichia coli LPS (1?mg/kg). We analyzed the food and water intake, body weight loss, and sucrose preference of the injected mice and then determined the microglia activation and inflammatory cytokine expression in the brains of LPS-treated mice and LPS-treated BV-2 microglial cells. In the TSA-pretreated mice, microglial activation was lower, anhedonia did not occur, and LPS-induced cognitive dysfunction (anorexia, weight loss, and social withdrawal) was attenuated. Moreover, mRNA expression of HDAC2, HDAC5, indoleamine 2,3-dioxygenase (IDO), TNF-?, MCP-1, and IL-1? in the brain of LPS-challenged mice and in the LPS-treated BV-2 microglial cells was lower. TSA diminished LPS-induced inflammatory responses in the mouse brain and modulated the cytokine-associated changes in cognitive function, which might be specifically related to reducing HDAC2 and HDAC5 expression. PMID:26273133

  19. Mechanism of interaction of optimized Limulus-derived cyclic peptides with endotoxins: thermodynamic, biophysical and microbiological analysis

    PubMed Central

    Andrä, Jörg; Howe, Jörg; Garidel, Patrick; Rössle, Manfred; Richter, Walter; Leiva-León, José; Moriyon, Ignacio; Bartels, Rainer; Gutsmann, Thomas; Brandenburg, Klaus

    2007-01-01

    On the basis of formerly investigated peptides corresponding to the endotoxin-binding domain from LALF [Limulus anti-LPS (lipopolysaccharide) factor], a protein from Limulus polyphemus, we have designed and synthesized peptides of different lengths with the aim of obtaining potential therapeutic agents against septic shock syndrome. For an understanding of the mechanisms of action, we performed a detailed physicochemical and biophysical analysis of the interaction of rough mutant LPS with these peptides by applying FTIR (Fourier-transform infrared) spectroscopy, SAXS (small-angle X-ray scattering), calorimetric techniques [DSC (differential scanning calorimetry) and ITC (isothermal titration calorimetry)] and FFTEM (freeze-fracture transmission electron microscopy). Also, the action of the peptides on bacteria of different origin in microbial assays was investigated. Using FTIR and DSC, our results indicated a strong fluidization of the lipid A acyl chains due to peptide binding, with a decrease in the endothermic melting enthalpy change of the acyl chains down to a complete disappearance in the 1:0.5 to 1:2 [LPS]:[peptide] molar ratio range. Via ITC, it was deduced that the binding is a clearly exothermic process which becomes saturated at a 1:0.5 to 1:2 [LPS]:[peptide] molar ratio range. The results obtained with SAXS indicated a drastic change of the aggregate structures of LPS into a multilamellar stack, which was visualized in electron micrographs as hundreds of lamellar layers. This can be directly correlated with the inhibition of the LPS-induced production of tumour necrosis factor ? in human mononuclear cells, but not with the action of the peptides on bacteria. PMID:17501719

  20. Age-related sensitivity to endotoxin-induced liver inflammation: Implication of inflammasome/IL-1? for steatohepatitis

    PubMed Central

    Chung, Ki Wung; Lee, Eun Kyeong; Kim, Dae Hyun; An, Hye Jin; Kim, Nam Deuk; Im, Dong Soon; Lee, Jaewon; Yu, Byung Pal; Chung, Hae Young

    2015-01-01

    Aging is associated with increased vulnerability to inflammatory challenge. However, the effects of altered inflammatory response on the metabolic status of tissues or organs are not well documented. In this study, we present evidence demonstrating that lipopolysaccharide (LPS)-induced upregulation of the inflammasome/IL-1? pathway is accompanied with an increased inflammatory response and abnormal lipid accumulation in livers of aged rats. To monitor the effects of aging on LPS-induced inflammation, we administered LPS (2 mg kg?1) to young (6-month old) and aged (24-month old) rats and found abnormal lipid metabolism in only aged rats with increased lipid accumulation in the liver. This lipid accumulation in the liver was due to the dysregulation of PPAR? and SREBP1c. We also observed severe liver inflammation in aged rats as indicated by increased ALT levels in serum and increased Kupffer cells in the liver. Importantly, among many inflammation-associated factors, the aged rat liver showed chronically increased IL-1? production. Increased levels of IL-1? were caused by the upregulation of caspase-1 activity and inflammasome activation. In vitro studies with HepG2 cells demonstrated that treatment with IL-1? significantly induced lipid accumulation in hepatocytes through the regulation of PPAR? and SREBP1c. In summary, we demonstrated that LPS-induced liver inflammation and lipid accumulation were associated with a chronically overactive inflammasome/IL-1? pathway in aged rat livers. Based on the present findings, we propose a mechanism of aging-associated progression of steatohepatitis induced by endotoxin, delineating a pathogenic role of the inflammasome/IL-1? pathway involved in lipid accumulation in the liver. PMID:25847140

  1. A low-protein diet combined with low-dose endotoxin leads to changes in glucose homeostasis in weanling rats.

    PubMed

    Bandsma, Robert H J; Ackerley, Cameron; Koulajian, Khajag; Zhang, Ling; van Zutphen, Tim; van Dijk, Theo H; Xiao, Changting; Giacca, Adria; Lewis, Gary F

    2015-09-01

    Severe malnutrition is a leading cause of global childhood mortality, and infection and hypoglycemia or hyperglycemia are commonly present. The etiology behind the changes in glucose homeostasis is poorly understood. Here, we generated an animal model of severe malnutrition with and without low-grade inflammation to investigate the effects on glucose homeostasis. Immediately after weaning, rats were fed diets containing 5 [low-protein diet (LP)] or 20% protein [control diet (CTRL)], with or without repeated low-dose intraperitoneal lipopolysaccharide (LPS; 2 mg/kg), to mimic inflammation resulting from infections. After 4 wk on the diets, hyperglycemic clamps or euglycemic hyperinsulinemic clamps were performed with infusion of [U-(13)C6]glucose and [2-(13)C]glycerol to assess insulin secretion, action, and hepatic glucose metabolism. In separate studies, pancreatic islets were isolated for further analyses of insulin secretion and islet morphometry. Glucose clearance was reduced significantly by LP feeding alone (16%) and by LP feeding with LPS administration (43.8%) compared with control during the hyperglycemic clamps. This was associated with a strongly reduced insulin secretion in LP-fed rats in vivo as well as ex vivo in islets but signficantly enhanced whole body insulin sensitivity. Gluconeogenesis rates were unaffected by LP feeding, but glycogenolysis was higher after LP feeding. A protein-deficient diet in young rats leads to a susceptibility to low-dose endotoxin-induced impairment in glucose clearance with a decrease in the islet insulin secretory pathway. A protein-deficient diet is associated with enhanced peripheral insulin sensitivity but impaired insulin-mediated suppression of hepatic glycogenolysis. PMID:26152763

  2. Volatile anesthetic sevoflurane ameliorates endotoxin-induced acute lung injury via microRNA modulation in rats

    PubMed Central

    OTSUKI, TATSURO; ISHIKAWA, MASASHI; HORI, YOKO; GOTO, GENTARO; SAKAMOTO, ATSUHIRO

    2015-01-01

    Volatile anesthetics have a lung protective effect in acute lung injury (ALI). Our previous study showed sevoflurane affects the expression of microRNA (miRNA) that control various physiological systems by regulating messenger RNA (mRNA) expression. However, the association between the anti-inflammatory effect of sevoflurane and miRNAs modulation remains unknown. The aim of the present study was to investigate the effect of sevoflurane and the expression of miRNAs in an endotoxin-induced ALI model in rats. Wistar rats were randomly assigned to three groups [lipopolysaccharide (LPS), LPS-sevoflurane and control; n=8/group]. All the rats were mechanically ventilated and intravenously-administered LPS (saline as control). Two hours post-injury, general anaesthesia was performed for 4 h with 2% sevoflurane (LPS-sevoflurane). The LPS and the control groups did not receive anaesthesia. The severity of ALI was evaluated by partial pressure of oxygen/fraction of inspired oxygen and the mRNA expression of inflammatory cytokine. The miRNA expression in lung tissue was analyzed by a reverse transcription-quantitative polymerase chain reaction. LPS caused ALI, evidenced by the impairment of pulmonary function and increased mRNA levels of tumor necrosis factor-?, interleukin-6 and nuclear factor-?B. Sevoflurane improved pulmonary function and inhibited the increased mRNAs. Of the 219 miRNAs detected, 15 and nine miRNAs were significantly changed in the LPS and LPS-sevoflurane group, respectively. In the LPS-sevoflurane group, the expression of several miRNAs that regulate inflammation was significantly changed compared to the LPS group. In conclusion, the present data showed that sevoflurane influences the expression of the miRNAs that regulate inflammation. This result suggests that the changes in miRNA expression are involved in the lung protective mechanisms of volatile anesthetics. PMID:26137246

  3. Biomarkers of oxidative stress study VI. Endogenous plasma antioxidants fail as useful biomarkers of endotoxin-induced oxidative stress.

    PubMed

    Kadiiska, Maria B; Peddada, Shyamal; Herbert, Ronald A; Basu, Samar; Hensley, Kenneth; Jones, Dean P; Hatch, Gary E; Mason, Ronald P

    2015-04-01

    This is the newest report in a series of publications aiming to identify a blood-based antioxidant biomarker that could serve as an in vivo indicator of oxidative stress. The goal of the study was to test whether acutely exposing Göttingen mini pigs to the endotoxin lipopolysaccharide (LPS) results in a loss of antioxidants from plasma. We set as a criterion that a significant effect should be measured in plasma and seen at both doses and at more than one time point. Animals were injected with two doses of LPS at 2.5 and 5 µg/kg iv. Control plasma was collected from each animal before the LPS injection. After the LPS injection, plasma samples were collected at 2, 16, 48, and 72 h. Compared with the controls at the same time point, statistically significant losses were not found for either dose at multiple time points in any of the following potential markers: ascorbic acid, tocopherols (?, ?, ?), ratios of GSH/GSSG and cysteine/cystine, mixed disulfides, and total antioxidant capacity. However, uric acid, total GSH, and total Cys were significantly increased, probably because LPS had a harmful effect on the liver. The leakage of substances from damaged cells into the plasma may have increased plasma antioxidant concentrations, making changes difficult to interpret. Although this study used a mini-pig animal model of LPS-induced oxidative stress, it confirmed our previous findings in different rat models that measurement of antioxidants in plasma is not useful for the assessment of oxidative damage in vivo. PMID:25614459

  4. Dexamethazone protects against Escherichia coli induced sickness behavior in rats.

    PubMed

    Hanaa-Mansour, A; Hassan, Wedad A; Georgy, Gehan S

    2016-01-01

    Systemic bacterial infection results in systemic inflammatory response syndrome due to the release of lipopolysaccharide (LPS) in blood that can lead to multiple organ failure, shock, and potentially death. Other impact, LPS exposure produces robust increase in anxiety-like behavior, suppression of locomotor, exploratory activity, and reduced social behavior. The therapeutic use of glucocorticoids in septic shock remains one of the first-aid approaches for their anti-inflammatory properties. The aim of this study was to evaluate the possible protective effect of dexamethazone (DEX), the most commonly used corticosteroid, against Escherichia coli (E. coli) immunohistochemical changes and neurobehavioral dysfunction. To this end, male Sprague-Dawley rats were divided into four groups; (1) Control group (2) E. coli infected group, where animals received 0.2ml of 24h growth of E. coli suspension in nutrient broth containing approximately 1.8×10(8)cfu/ml i.p for once, 48h before sacrificing (3) DEX (20mg/kg, i.p, 3 days) treated group (4) DEX and E. coli treated group. The results revealed that DEX significantly protected animals against most E. coli-induced behavioral deficits, reduced signs of cognitive impairment. DEX also reduced the LPS-evoked rise in C-reactive protein (CRP), Interferon gamma (IF?), as well as, expression of Caspase-3. In conclusion, DEX provides neuroprotection against E. coli-associated neurobehavioral and immunological changes via its anti-inflammatory and immunomodulatory effects. PMID:26541583

  5. Evaluation Of Airborne Endotoxin Concentrations Associated With Management Of Crop Grown On Applied Biosolids

    EPA Science Inventory

    Public health concerns have been expressed regarding inhalation exposure associated with the application of biosolids on cropland, which is due to the potential aerosolization of microorganisms, cell wall products, volatile chemicals, and nuisance odors. Endotoxin is a component...

  6. Importance of Lipopolysaccharide and Cyclic ?-1,2-Glucans in Brucella-Mammalian Infections

    PubMed Central

    Haag, Andreas F.; Myka, Kamila K.; Arnold, Markus F. F.; Caro-Hernández, Paola; Ferguson, Gail P.

    2010-01-01

    Brucella species are the causative agents of one of the most prevalent zoonotic diseases: brucellosis. Infections by Brucella species cause major economic losses in agriculture, leading to abortions in infected animals and resulting in a severe, although rarely lethal, debilitating disease in humans. Brucella species persist as intracellular pathogens that manage to effectively evade recognition by the host's immune system. Sugar-modified components in the Brucella cell envelope play an important role in their host interaction. Brucella lipopolysaccharide (LPS), unlike Escherichia coli LPS, does not trigger the host's innate immune system. Brucella produces cyclic ?-1,2-glucans, which are important for targeting them to their replicative niche in the endoplasmic reticulum within the host cell. This paper will focus on the role of LPS and cyclic ?-1,2-glucans in Brucella-mammalian infections and discuss the use of mutants, within the biosynthesis pathway of these cell envelope structures, in vaccine development. PMID:21151694

  7. Importance of Lipopolysaccharide and Cyclic ?-1,2-Glucans in Brucella-Mammalian Infections.

    PubMed

    Haag, Andreas F; Myka, Kamila K; Arnold, Markus F F; Caro-Hernández, Paola; Ferguson, Gail P

    2010-01-01

    Brucella species are the causative agents of one of the most prevalent zoonotic diseases: brucellosis. Infections by Brucella species cause major economic losses in agriculture, leading to abortions in infected animals and resulting in a severe, although rarely lethal, debilitating disease in humans. Brucella species persist as intracellular pathogens that manage to effectively evade recognition by the host's immune system. Sugar-modified components in the Brucella cell envelope play an important role in their host interaction. Brucella lipopolysaccharide (LPS), unlike Escherichia coli LPS, does not trigger the host's innate immune system. Brucella produces cyclic ?-1,2-glucans, which are important for targeting them to their replicative niche in the endoplasmic reticulum within the host cell. This paper will focus on the role of LPS and cyclic ?-1,2-glucans in Brucella-mammalian infections and discuss the use of mutants, within the biosynthesis pathway of these cell envelope structures, in vaccine development. PMID:21151694

  8. Transport of lipopolysaccharide to the Gram-negative bacterial cell surface.

    PubMed

    Putker, Florian; Bos, Martine P; Tommassen, Jan

    2015-11-01

    Lipopolysaccharides (LPS) are major lipidic components of the outer membrane of most Gram-negative bacteria. They form a permeability barrier that protects these bacteria from harmful compounds in the environment. In addition, they are important signaling molecules for the innate immune system. The mechanism of transport of these molecules to the bacterial cell surface has remained enigmatic for a long time. However, intense research during the last decade, particularly in Escherichia coli and Neisseria meningitidis, has led to the identification of the machinery that mediates LPS transport. In this review, we summarize the current knowledge of the LPS transport machinery and provide an overview of the distribution of the components of this machinery among diverse bacteria, even organisms that don't produce LPS. We also discuss the current insights in the regulation of LPS biosynthesis. PMID:26038291

  9. Comparison between the polymyxins and gentamicin in preventing endotoxin-induced intravascular coagulation and leukopenia.

    PubMed

    Corrigan, J J; Bell, B M

    1971-11-01

    Three antimicrobial agents were evaluated as to their ability to neutralize the toxic effects of endotoxin in rabbits. These consisted of two cyclic polypeptides, polymyxin B sulfate and colymycin M (sodium colistimethate), and an aminoglycoside, gentamicin sulfate. Polymyxin B regularly prevented endotoxin-induced leukopenia, thrombocytopenia, and disseminated intravascular coagulation. Colymycin M had similar activity but was not as effective as polymyxin B. Gentamicin demonstrated no neutralizing ability in this study. PMID:4343409

  10. E. coli enteritis

    MedlinePLUS

    ... is swelling (inflammation) of the small intestine from Escherichia coli ( E. coli ) bacteria. It is the most common ... Vomiting (rare) Symptoms of a rare but severe E. coli infection include: Bruises that happen easily Pale skin Red ...

  11. NMR Structures and Interactions of Antimicrobial Peptides with Lipopolysaccharide: Connecting Structures to Functions.

    PubMed

    Bhattacharjya, Surajit

    2016-01-01

    Antimicrobial peptides (AMPs) establish the first line of host defense mechanism against invading microorganisms including bacteria, viruses, fungi and parasites. In recent years, emergence and spread of antibiotic resistance bacterial pathogens have dawn considerable interest in investigations of AMPs. The ability of AMPs to exert lethality against multiple drug-resistant (MDR) bacteria has incited promising avenues for antibiotic development. As a mode of action, most AMPs perturb the membrane organization of bacterial cells. The outer membrane lipopolysaccharide (LPS) of Gram-negative bacteria establishes a superior permeability barrier, in contrast to the peptidoglycan layer of Gram-positive bacteria. Due to LPS barrier, development of antibiotics for drug resistant Gram- negative bacteria are more complicated, with only fewer compounds in the pipeline. Recent studies have demonstrated that LPS actively regulate mode of action of AMPs on the lethality of Gram-negative bacteria. LPS, also known as endotoxin, is the primary agent for septic shock syndromes in intensive care unit killing over 120,000 people in the USA. Currently, anti-sepsis therapies are greatly lacking. Therefore, LPS has been considered as a target for the development of antimicrobial and antisepsis drugs. In recent and past few years, 3-D structures and interactions of a number of AMPs have been determined in complex with LPS micelles. These studies have generated molecular insights towards mode of action and synergistic activity of AMPs in the outer membrane. In this review, atomic resolution structures and interactions of potent AMPs with LPS are discussed providing novel insights of their mode of action. PMID:26139110

  12. Lipopolysaccharide enhances apoptosis of corpus luteum in isolated perfused bovine ovaries in vitro.

    PubMed

    Lüttgenau, J; Möller, B; Kradolfer, D; Wellnitz, O; Bruckmaier, R M; Miyamoto, A; Ulbrich, S E; Bollwein, H

    2016-01-01

    Lipopolysaccharide (LPS), the endotoxin of Gram-negative bacteria, has detrimental effects on the structure and function of bovine corpus luteum (CL) in vivo. The objective was to investigate whether these effects were mediated directly by LPS or via LPS-induced release of PGF2?. Bovine ovaries with a mid-cycle CL were collected immediately after slaughter and isolated perfused for 240 min. After 60 min of equilibration, LPS (0.5 ?g/ml) was added to the medium of five ovaries, whereas an additional six ovaries were not treated with LPS (control). After 210 min of perfusion, all ovaries were treated with 500 iu of hCG. In the effluent perfusate, concentrations of progesterone (P4) and PGF2? were measured every 10 and 30 min, respectively. Punch biopsies of the CL were collected every 60 min and used for RT-qPCR to evaluate mRNA expression of receptors for LPS (TLR2, -4) and LH (LHCGR); the cytokine TNFA; steroidogenic (STAR, HSD3B), angiogenic (VEGFA121, FGF2), and vasoactive (EDN1) factors; and factors of prostaglandin synthesis (PGES, PGFS, PTGFR) and apoptosis (CASP3, -8, -9). Treatment with LPS abolished the hCG-induced increase in P4 (P?0.05); however, there was a tendency (P=0.10) for increased release of PGF2? at 70 min after LPS challenge. Furthermore, mRNA abundance of TLR2, TNFA, CASP3, CASP8, PGES, PGFS, and VEGFA121 increased (P?0.05) after LPS treatment, whereas all other factors remained unchanged (P>0.05). In conclusion, reduced P4 responsiveness to hCG in LPS-treated ovaries in vitro was not due to reduced steroidogenesis, but was attributed to enhanced apoptosis. However, an impact of luteal PGF2? could not be excluded. PMID:26483517

  13. Lipopolysaccharide-Induced Dynamic Lipid Membrane Reorganization: Tubules, Perforations, and Stacks

    PubMed Central

    Adams, Peter G.; Lamoureux, Loreen; Swingle, Kirstie L.; Mukundan, Harshini; Montaño, Gabriel A.

    2014-01-01

    Lipopolysaccharide (LPS) is a unique lipoglycan, with two major physiological roles: 1), as a major structural component of the outer membrane of Gram-negative bacteria and 2), as a highly potent mammalian toxin when released from cells into solution (endotoxin). LPS is an amphiphile that spontaneously inserts into the outer leaflet of lipid bilayers to bury its hydrophobic lipidic domain, leaving the hydrophilic polysaccharide chain exposed to the exterior polar solvent. Divalent cations have long been known to neutralize and stabilize LPS in the outer membrane, whereas LPS in the presence of monovalent cations forms highly mobile negatively-charged aggregates. Yet, much of our understanding of LPS and its interactions with the cell membrane does not take into account its amphiphilic biochemistry and charge polarization. Herein, we report fluorescence microscopy and atomic force microscopy analysis of the interaction between LPS and fluid-phase supported lipid bilayer assemblies (sLBAs), as model membranes. Depending on cation availability, LPS induces three remarkably different effects on simple sLBAs. Net-negative LPS-Na+ leads to the formation of 100-?m-long flexible lipid tubules from surface-associated lipid vesicles and the destabilization of the sLBA resulting in micron-size hole formation. Neutral LPS-Ca2+ gives rise to 100-?m-wide single- or multilamellar planar sheets of lipid and LPS formed from surface-associated lipid vesicles. Our findings have important implications about the physical interactions between LPS and lipids and demonstrate that sLBAs can be useful platforms to study the interactions of amphiphilic virulence factors with cell membranes. Additionally, our study supports the general phenomenon that lipids with highly charged or bulky headgroups can promote highly curved membrane architectures due to electrostatic and/or steric repulsions. PMID:24896118

  14. Time-dependent changes in inhibitory action of lipopolysaccharide on intestinal motility in rat

    PubMed Central

    MIKAWA, Shoma; OHTA, Yasuhiro; KAJI, Noriyuki; ISLAM, Md Shafiqul; MURATA, Takahisa; OZAKI, Hiroshi; HORI, Masatoshi

    2015-01-01

    Endotoxin causes gastrointestinal motility disorder. Aim of this study is to clarify inhibitory mechanisms of lipopolysaccharide (LPS) on smooth muscle contraction in rat ileum. Ileal tissues were isolated from control rat or from LPS-induced peritonitis model rat. Treatment with LPS inhibited carbachol (CCh)-mediated contraction in a time-dependent manner. Cyclooxygenase-2 (COX-2) and inducible nitric oxide synthase (iNOS) genes were also upregulated, but iNOS expression was preceded by a rising of COX-2. All subtypes of prostaglandin E2 (PGE2) receptors (EP1-EP4) were expressed in ileum, and PGE2 and selective EP2 or EP4 agonist inhibited CCh-mediated contraction. Selective iNOS inhibitor did not reverse LPS-induced inhibition of contraction by CCh at 1 and 2 hr, but reduced the inhibitory action at 4 hr after the LPS treatment. COX-2 inhibitor reversed the inhibitory action by LPS in all exposure time. Finally, in ileal tissues isolated from peritonitis model rat, iNOS expression was upregulated only at 4 hr after LPS administration, resulting in enhanced inhibitory action of LPS against CCh-induced contraction. In conclusion, LPS induces COX-2 to produce PGE2, which initially activates EP2 and/or EP4 on smooth muscle cells to inhibit the contractility in early phase of LPS exposure. Moreover, in late phase of LPS treatment, iNOS is expressed to produce NO, which in turn inhibited the contraction by CCh. The inhibitory cascade is similar in the ileum isolated from peritonitis model rat, indicating time-dependent changes of inhibitory action by LPS on intestinal motility in peritonitis. PMID:26051129

  15. Exogenous normal lymph reduces liver injury induced by lipopolysaccharides in rats

    PubMed Central

    Zhao, Z.G.; Zhang, L.L.; Niu, C.Y.; Zhang, J.

    2014-01-01

    The liver is one of the target organs damaged by septic shock, wherein the spread of endotoxins begins. This study aimed to investigate the effects of exogenous normal lymph (ENL) on lipopolysaccharide (LPS)-induced liver injury in rats. Male Wistar rats were randomly divided into sham, LPS, and LPS+ENL groups. LPS (15 mg/kg) was administered intravenously via the left jugular vein to the LPS and LPS+ENL groups. At 15 min after the LPS injection, saline or ENL without cell components (5 mL/kg) was administered to the LPS and LPS+ENL groups, respectively, at a rate of 0.5 mL/min. Hepatocellular injury indices and hepatic histomorphology, as well as levels of P-selectin, intercellular adhesion molecule 1 (ICAM-1), myeloperoxidase (MPO), and Na+-K+-ATPase, were assessed in hepatic tissues. Liver tissue damage occurred after LPS injection. All levels of alanine aminotransferase (ALT) and aspartate aminotransferase (AST) in plasma as well as the wet/dry weight ratio of hepatic tissue in plasma increased. Similarly, P-selectin, ICAM-1, and MPO levels in hepatic tissues were elevated, whereas Na+-K+-ATPase activity in hepatocytes decreased. ENL treatment lessened hepatic tissue damage and decreased levels of AST, ALT, ICAM-1, and MPO. Meanwhile, the treatment increased the activity of Na+-K+-ATPase. These results indicated that ENL could alleviate LPS-induced liver injury, thereby suggesting an alternative therapeutic strategy for the treatment of liver injury accompanied by severe infection or sepsis. PMID:24519128

  16. Effect of lipopolysaccharide on the biological characteristics of human skin fibroblasts and hypertrophic scar tissue formation.

    PubMed

    Yang, Hongming; Hu, Chao; Li, Fengyu; Liang, Liming; Liu, Lingying

    2013-06-01

    Burn injury-mediated destruction of the skin barrier normally induces microbial invasion, in turn leading to the development of systemic infection and occasional septic shock by the release of endotoxins. The objective of this work was to study the influence of lipopolysaccharide (LPS) on the biological characteristics of normal skin fibroblasts and to elucidate the influence of LPS in the initial stage of skin wound healing. Twenty patients with hypertrophic scar in proliferative stage were selected randomly and primary cultures were established from fibroblasts derived from their hypertrophic scar tissue and normal skin. Normal skin fibroblasts of passage 3 were stimulated with different concentrations of LPS. LPS stimulated the proliferation and collagen synthesis of fibroblasts within a certain extent of concentrations (0.005-0.5 ?g/mL) (P < 0.05), whereas at a concentration of 1 ?g/mL inhibited the proliferation and collagen synthesis of fibroblasts (P < 0.05). Collagen synthesis by normal skin fibroblasts after LPS stimulation mimicked those derived from hypertrophic scar tissue. LPS of 0.1 ?g/mL had significant effect on normal skin fibroblasts-continuous passage of these fibroblasts resulted in ultrastructural pattern similar to fibroblasts derived from hypertrophic scar tissue, and the findings was substantiated by hematoxylin and eosin staining and immunohistochemistry detection of proliferation cell nuclear antigen, type I procollagen and ?-smooth muscle actin. Our results suggest that LPS might convert normal skin fibroblasts to hypertrophic scar tissue fibroblasts and participate in the formation of hypertrophic scar; hence, appropriate concentration of LPS may have no effect or be beneficial to skin wound healing, whereas excessive concentration of LPS may delay the time of wound healing. PMID:23653386

  17. NMR-based Structural Analysis of the Complete Rough-type Lipopolysaccharide Isolated from Capnocytophaga canimorsus*

    PubMed Central

    Zähringer, Ulrich; Ittig, Simon; Lindner, Buko; Moll, Hermann; Schombel, Ursula; Gisch, Nicolas; Cornelis, Guy R.

    2014-01-01

    We here describe the NMR analysis of an intact lipopolysaccharide (LPS, endotoxin) in water with 1,2-dihexanoyl-sn-glycero-3-phosphocholine as detergent. When HPLC-purified rough-type LPS of Capnocytophaga canimorsus was prepared, 13C,15N labeling could be avoided. The intact LPS was analyzed by homonuclear (1H) and heteronuclear (1H,13C, and 1H,31P) correlated one- and two-dimensional NMR techniques as well as by mass spectrometry. It consists of a penta-acylated lipid A with an ?-linked phosphoethanolamine attached to C-1 of GlcN (I) in the hybrid backbone, lacking the 4?-phosphate. The hydrophilic core oligosaccharide was found to be a complex hexasaccharide with two mannose (Man) and one each of 3-deoxy-d-manno-oct-2-ulosonic acid (Kdo), Gal, GalN, and l-rhamnose residues. Position 4 of Kdo is substituted by phosphoethanolamine, also present in position 6 of the branched ManI residue. This rough-type LPS is exceptional in that all three negative phosphate residues are “masked” by positively charged ethanolamine substituents, leading to an overall zero net charge, which has so far not been observed for any other LPS. In biological assays, the corresponding isolated lipid A was found to be endotoxically almost inactive. By contrast, the intact rough-type LPS described here expressed a 20,000-fold increased endotoxicity, indicating that the core oligosaccharide significantly contributes to the endotoxic potency of the whole rough-type C. canimorsus LPS molecule. Based on these findings, the strict view that lipid A alone represents the toxic center of LPS needs to be reassessed. PMID:24993825

  18. Polymyxin B immobilized on cross-linked cellulose microspheres for endotoxin adsorption.

    PubMed

    Cao, Xiaodong; Zhu, Biyan; Zhang, Xufeng; Dong, Hua

    2016-01-20

    Cross-linked cellulose microspheres (CL-CMs) were successfully prepared by inverse crosslinking suspension method. NaOH/urea aqueous solution was used as solvent to dissolve cellulose at low temperature. The microspheres presented good spherical shape and monodispersity, which were applied to synthesize endotoxin adsorbent with polymyxin B (PMB) as ligand. The adsorbent showed good adsorption capability on endotoxin in physiologic saline solution and the maximum adsorption capacity was 3605EU/g (1EU=100pg). It was worth noting that more than 70% of endotoxin could be effectively removed from the human plasma with the initial concentration of endotoxin ranged from 1EU/mL to 5EU/mL. The dynamic adsorption efficiency of endotoxin was 72.3% at the plasma perfusion rate of 300mL/h with the endotoxin concentration of 4EU/mL, while the variation of plasma protein before and after adsorption was only 8.9%. It suggests that the PMB immobilized CL-CMs have great potential application in clinical blood purification. PMID:26572323

  19. Immunogenic mimics of Brucella lipopolysaccharide epitopes.

    PubMed

    Beninati, Concetta; Garibaldi, Manuela; Lo Passo, Carla; Mancuso, Giuseppe; Papasergi, Salvatore; Garufi, Gabriella; Pernice, Ida; Teti, Giuseppe; Felici, Franco

    2009-10-01

    Brucella melitensis and Brucella abortus are responsible for brucellosis in bovine and ovine species and for Malta fever in humans. The lipopolysaccharide (LPS) of Brucella is an important virulence factor and can elicit protective antibodies. Because of their potential importance in vaccine design and in serological diagnosis, we developed peptides mimicking the antigenic properties of distinctive antigenic determinants of Brucella LPS. These peptides were selected from several phage display random peptide libraries for their ability to bind monoclonal antibodies directed against the A- or C-type epitopes of Brucella LPS. Plasmids encoding for two of the isolated peptides induced, after DNA immunization, LPS-specific antibody responses. Although these responses were only moderate in extent, these data further suggest the feasibility of using peptide mimics of carbohydrate epitopes as immunogens, a property which may be useful in the design of novel anti-Brucella vaccines. PMID:19631246

  20. Primo Vessel Stressed by Lipopolysaccharide in Rabbits.

    PubMed

    Lee, Hye-Rie; Rho, Min-Suk; Hong, Ye-Ji; Ha, Yae-Eun; Kim, Ji-Young; Noh, Young-Il; Park, Do-Young; Kim, Chang-Kyu; Kim, Eun-Jung; Jang, In-Ho; Kang, Suk-Yun; Lee, Sang-Suk

    2015-12-01

    For tracking the primo vascular system, we observed the primo vessels in vivo in situ using the lipopolysaccharide (LPS) response in the lymphatic vessels of a rabbit. Injection of LPS (200 ?g/kg) into the lymph nodes resulted in greatly stained primo vessels, which were swollen in some cases. We were able to obtain comparative images through alcian blue and diaminobenzidine staining, which clearly showed different morphologies of the primo vessels. The mechanism causing the response of the primo vessels to the injected LPS is still unclear; however, these results might be a first attempt at giving an explanation of the function of the primo vascular system and identifying the changes in the structure and function of the primo vascular system in response to an external stimulus such as an injection of LPS. PMID:26742914

  1. Epigenetic Alterations Induced by Bacterial Lipopolysaccharides.

    PubMed

    Chiariotti, Lorenzo; Coretti, Lorena; Pero, Raffaela; Lembo, Francesca

    2016-01-01

    Lipopolysaccharide (LPS) is one of the principal bacterial products known to elicit inflammation. Cells of myeloid lineage such as monocytes and macrophages, but also epithelial cells give rise to an inflammatory response upon LPS stimulation. This phenomenon implies reprogramming of cell specific gene expression that can occur through different mechanisms including epigenetic modifications. Given their intrinsic nature, epigenetic modifications may be involved both in the acute response to LPS and in the establishment of a preconditioned genomic state (epigenomic memory) that may potentially influence the host response to further contacts with microorganisms. Information has accumulated during the last years aimed at elucidating the epigenetic mechanisms which underlie the cellular LPS response. These findings, summarized in this chapter, will hopefully be a good basis for a definition of the complete cascade of LPS-induced epigenetic events and their biological significance in different cell types. PMID:26659265

  2. Cyanobacterial lipopolysaccharides and human health – a review

    PubMed Central

    Stewart, Ian; Schluter, Philip J; Shaw, Glen R

    2006-01-01

    Cyanobacterial lipopolysaccharide/s (LPS) are frequently cited in the cyanobacteria literature as toxins responsible for a variety of heath effects in humans, from skin rashes to gastrointestinal, respiratory and allergic reactions. The attribution of toxic properties to cyanobacterial LPS dates from the 1970s, when it was thought that lipid A, the toxic moiety of LPS, was structurally and functionally conserved across all Gram-negative bacteria. However, more recent research has shown that this is not the case, and lipid A structures are now known to be very different, expressing properties ranging from LPS agonists, through weak endotoxicity to LPS antagonists. Although cyanobacterial LPS is widely cited as a putative toxin, most of the small number of formal research reports describe cyanobacterial LPS as weakly toxic compared to LPS from the Enterobacteriaceae. We systematically reviewed the literature on cyanobacterial LPS, and also examined the much lager body of literature relating to heterotrophic bacterial LPS and the atypical lipid A structures of some photosynthetic bacteria. While the literature on the biological activity of heterotrophic bacterial LPS is overwhelmingly large and therefore difficult to review for the purposes of exclusion, we were unable to find a convincing body of evidence to suggest that heterotrophic bacterial LPS, in the absence of other virulence factors, is responsible for acute gastrointestinal, dermatological or allergic reactions via natural exposure routes in humans. There is a danger that initial speculation about cyanobacterial LPS may evolve into orthodoxy without basis in research findings. No cyanobacterial lipid A structures have been described and published to date, so a recommendation is made that cyanobacteriologists should not continue to attribute such a diverse range of clinical symptoms to cyanobacterial LPS without research confirmation. PMID:16563160

  3. Phenyl-?-D-Glucopyranoside Exhibits Anti-inflammatory Activity in Lipopolysaccharide-Activated RAW 264.7 Cells.

    PubMed

    Hwang, Su Jung; Lee, Hyo-Jong

    2015-01-01

    Phenyl-?-D-glucopyranoside is a component of Phellodendron amurense with anti-cancer and anti-inflammatory activities. In the present study, we investigated the role of phenyl-?-D-glucopyranoside in inflammation using lipopolysaccharide (LPS)-stimulated murine Raw 264.7 macrophages. Phenyl-?-D-glucopyranoside not only inhibited nitric oxide (NO) production but also significantly inhibited the expression of inducible NO synthase (iNOS) and cyclooxygenase-2 (COX-2) without inducing cytotoxicity. Phenyl-?-D-glucopyranoside also attenuated proinflammatory cytokines, including tumor necrosis factor-? (TNF-?), interleukin-1? (IL-1?) and other inflammation-related genes, such as IL-6 in a concentration-dependent manner. Furthermore, phenyl-?-D-glucopyranoside abolished increased adhesion, ninjurin 1 (Ninj1) expression, and matrix metalloproteinase (MMP) activity induced by endotoxin treatment. Finally, phenyl-?-D-glucopyranoside inhibited the nuclear translocation of nuclear factor-?B (NF-?B), which is one of the most important transcription factors involved in the inflammatory process. Taken together, phenyl-?-D-glucopyranoside may be beneficial for the prevention and treatment of anti-inflammatory diseases. PMID:25502067

  4. Effect of lipopolysaccharide administration on the number, phenotype and content of nuclear molecules in blood microparticles of normal human subjects.

    PubMed

    Soop, A; Hållström, L; Frostell, C; Wallén, H; Mobarrez, F; Pisetsky, D S

    2013-08-01

    Microparticles (MPs) are small membrane-bound vesicles that arise from activated and dying cells and promote inflammation and thrombosis. To characterize the in vivo release of MPs, we used flow cytometry to measure MPs in the blood of 15 healthy volunteers administered bacterial endotoxin (lipopolysaccharide or LPS) in the presence of a low dose of hydrocortisone with or without inhaled nitric oxide. MPs, defined as particles less than 1.0 ?m in size, were assessed following labelling for CD42a, CD14 and CD62E or CD144 antibodies to identify MPs from platelets (PMPs), monocytes (MMPs) and endothelial cells (EMPs). In addition, PMPs and MMPs were labelled with anti-HMGB1 and stained with SYTO13 to assess nuclear acid content. Administration of LPS led to an increase in the numbers of PMPs, MMPs and EMPs as defined by CD62E, as well as the number of MMPs and PMPs staining with anti-HMGB1 and SYTO13. Inhalation of NO did not influence these findings. Together, these studies show that LPS can increase levels of blood MPs and influence phenotype, including nuclear content. As such, particles may be a source of HMGB1 and other nuclear molecules in the blood during inflammation. PMID:23679665

  5. ?MSH blunts endotoxin-induced MuRF1 and atrogin-1 upregulation in skeletal muscle by modulating NF-?B and Akt/FoxO1 pathway.

    PubMed

    Martín, Ana Isabel; Gómez-SanMiguel, Ana Belén; Gómez-Moreira, Carolina; Villanúa, María Ángeles; López-Calderón, Asunción

    2014-01-01

    Alpha melanocyte stimulating hormone (?MSH) has been shown to have anti-inflammatory and anticachectic actions. We hypothesized that ?MSH administration could attenuate the effect of lipopolysaccharide (LPS) on the skeletal muscle through modifications in IGF-Akt-FoxO1 pathway, or/and in serum corticosterone. Adult male Wistar rats were injected with LPS and/or ?MSH. ?MSH administration reduced LPS-induced increase in liver TNF? and serum nitrites as well as NF-?B activation in skeletal muscle. In contrast, ?MSH was not able to prevent the stimulatory effect of LPS on serum concentration of ACTH and corticosterone. LPS decreased serum levels of IGF-I and IGFBP3 and their expression in the liver (P < 0.01). However IGFBP3 expression in the gastrocnemius was increased by LPS. Treatment with ?MSH prevented the effects of LPS on IGFBP3 but not on IGF-I. In the gastrocnemius ?MSH blocked LPS-induced decrease in pAkt as well as the increase in pNF-?B(p65), FoxO1, atrogin-1, and MuRF1 levels. These results suggest that ?MSH blunts skeletal muscle response to endotoxin by downregulating atrogenes and FoxO1 at least in part by controlling NF-?B activation and Akt signalling, but not through modifications in the secretion of corticosterone or IGF-I. PMID:25294954

  6. Sleep deprivation attenuates endotoxin-induced cytokine gene expression independent of day length and circulating cortisol in male Siberian hamsters (Phodopus sungorus).

    PubMed

    Ashley, Noah T; Walton, James C; Haim, Achikam; Zhang, Ning; Prince, Laura A; Fruchey, Allison M; Lieberman, Rebecca A; Weil, Zachary M; Magalang, Ulysses J; Nelson, Randy J

    2013-07-15

    Sleep is restorative, whereas reduced sleep leads to negative health outcomes, such as increased susceptibility to disease. Sleep deprivation tends to attenuate inflammatory responses triggered by infection or exposure to endotoxin, such as bacterial lipopolysaccharide (LPS). Previous studies have demonstrated that Siberian hamsters (Phodopus sungorus), photoperiodic rodents, attenuate LPS-induced fever, sickness behavior and upstream pro-inflammatory gene expression when adapted to short day lengths. Here, we tested whether manipulation of photoperiod alters the suppressive effects of sleep deprivation upon cytokine gene expression after LPS challenge. Male Siberian hamsters were adapted to long (16 h:8 h light:dark) or short (8 h:16 h light:dark) photoperiods for >10 weeks, and were deprived of sleep for 24 h using the multiple platform method or remained in their home cage. Hamsters received an intraperitoneal injection of LPS or saline (control) 18 h after starting the protocol, and were killed 6 h later. LPS increased liver and hypothalamic interleukin-1 (IL-1) and tumor necrosis factor-alpha (TNF) gene expression compared with vehicle. Among LPS-challenged hamsters, sleep deprivation reduced IL-1 mRNA levels in liver and hypothalamus, but not TNF. IL-1 attenuation was independent of circulating baseline cortisol, which did not increase after sleep deprivation. Conversely, photoperiod altered baseline cortisol, but not pro-inflammatory gene expression in sleep-deprived hamsters. These results suggest that neither photoperiod nor glucocorticoids influence the suppressive effect of sleep deprivation upon LPS-induced inflammation. PMID:23531821

  7. A signal-on electrochemical aptasensor for ultrasensitive detection of endotoxin using three-way DNA junction-aided enzymatic recycling and graphene nanohybrid for amplification

    NASA Astrophysics Data System (ADS)

    Bai, Lijuan; Chai, Yaqin; Pu, Xiaoyun; Yuan, Ruo

    2014-02-01

    Endotoxin, also known as lipopolysaccharide (LPS), is able to induce a strong immune response on its internalization into mammalian cells. To date, aptamer-based biosensors for LPS detection have been rarely reported. This work describes a new signal-on electrochemical aptasensor for the ultrasensitive detection of LPS by combining the three-way DNA hybridization process and nanotechnology-based amplification. With the help of DNA1 (associated with the concentration of target LPS), the capture probe hybridizes with DNA1 and the assistant probe to open its hairpin structure and form a ternary ``Y'' junction structure. The DNA1 can be released from the structure in the presence of nicking endonuclease to initiate the next hybridization process. Then a great deal of cleaved capture probe produced in the cyclic process can bind with DNA2-nanocomposite, which contains the electroactive toluidine blue (Tb) with the amplification materials graphene (Gra) and gold nanoparticles (AuNPs). Thus, an enhanced electrochemical signal can be easily read out. With the cascade signal amplification, this newly designed protocol provides an ultrasensitive electrochemical detection of LPS down to the femtogram level (8.7 fg mL-1) with a linear range of 6 orders of magnitude (from 10 fg mL-1 to 50 ng mL-1). Moreover, the high sensitivity and specificity make this method versatile for the detection of other biomolecules by changing the corresponding sequences of the capture probe and the assistant probe.

  8. The assay of endotoxin by intravenous injection of lead acetate-treated mice.

    PubMed

    Kuratsuka, K; Fujiwara, H

    1984-10-01

    A new intravenous endotoxin assay method (i.v. method) for the determination of very small amounts of endotoxin was studied in mice pre-treated intraperitoneally with lead acetate and was compared with an earlier intraperitoneal (i.p.) method in which both endotoxin and lead acetate were administered by the i.p. route. Linear dose-response relationships were obtained for both the i.v. and i.p. methods between logarithmic doses of endotoxin and the responses measured as body weight ratios on the first day. The range of the linearity was longer in the i.v. method than that in the i.p. method. In the i.v. method, linearity extended to much smaller doses of endotoxin than in the i.p. method. The slope of the dose-response line obtained by the i.v. method was flatter than that obtained by the i.p. method. The minimum detectable dose defined as the smallest dose of endotoxin producing a mean response statistically distinguishable from that of the control was in the nanogram order and smaller than that obtained by the i.p. method. Therefore the i.v. method may be more suitable than the i.p. method for detection of very small amounts of endotoxin. The non-parallelism of the dose-response lines obtained in lead acetate-treated and untreated mice was demonstrated in the i.v. method as well as in the i.p. method. PMID:6526827

  9. Airborne environmental endotoxin: a cross-validation of sampling and analysis techniques.

    PubMed Central

    Walters, M; Milton, D; Larsson, L; Ford, T

    1994-01-01

    A standard method for measurement of airborne environmental endotoxin was developed and field tested in a fiberglass insulation-manufacturing facility. This method involved sampling with a capillary-pore membrane filter, extraction in buffer using a sonication bath, and analysis by the kinetic-Limulus assay with resistant-parallel-line estimation (KLARE). Cross-validation of the extraction and assay method was performed by comparison with methanolysis of samples followed by 3-hydroxy fatty acid (3-OHFA) analysis by gas chromatography-mass spectrometry. Direct methanolysis of filter samples and methanolysis of buffer extracts of the filters yielded similar 3-OHFA content (P = 0.72); the average difference was 2.1%. Analysis of buffer extracts for endotoxin content by the KLARE method and by gas chromatography-mass spectrometry for 3-OHFA content produced similar results (P = 0.23); the average difference was 0.88%. The source of endotoxin was gram-negative bacteria growing in recycled washwater used to clean the insulation-manufacturing equipment. The endotoxin and bacteria become airborne during spray cleaning operations. The types of 3-OHFAs in bacteria cultured from the washwater, present in the washwater and in the air, were similar. Virtually all of the bacteria cultured from air and water were gram negative composed mostly of two species, Deleya aesta and Acinetobacter johnsonii. Airborne countable bacteria correlated well with endotoxin (r2 = 0.64). Replicate sampling showed that results with the standard sampling, extraction, and Limulus assay by the KLARE method were highly reproducible (95% confidence interval for endotoxin measurement +/- 0.28 log10). These results demonstrate the accuracy, precision, and sensitivity of the standard procedure proposed for airborne environmental endotoxin. PMID:8161191

  10. Comparison of endotoxin and particle bounce in Marple cascade samplers with and without impaction grease.

    PubMed

    Kirychuk, Shelley P; Reynolds, Stephen J; Koehncke, Niels; Nakatsu, J; Mehaffy, John

    2009-01-01

    The health of persons engaged in agricultural activities are often related or associated with environmental exposures in their workplace. Accurately measuring, analyzing, and reporting these exposures is paramount to outcomes interpretation. This paper describes issues related to sampling air in poultry barns with a cascade impactor. Specifically, the authors describe how particle bounce can affect measurement outcomes and how the use of impaction grease can impact particle bounce and laboratory analyses such as endotoxin measurements. This project was designed to (1) study the effect of particle bounce in Marple cascade impactors that use polyvinyl chloride (PVC) filters; (2) to determine the effect of impaction grease on endotoxin assays when sampling poultry barn dust. A pilot study was undertaken utilizing six-stage Marple cascade impactors with PVC filters. Distortion of particulate size distributions and the effects of impaction grease on endotoxin analysis in samples of poultry dust distributed into a wind tunnel were studied. Although there was no significant difference in the overall dust concentration between utilizing impaction grease and not, there was a greater than 50% decrease in the mass median aerodynamic diameter (MMAD) values when impaction grease was not utilized. There was no difference in airborne endotoxin concentration or endotoxin MMAD between filters treated with impaction grease and those not treated. The results indicate that particle bounce should be a consideration when sampling poultry barn dust with Marple samplers containing PVC filters with no impaction grease. Careful consideration should be given to the utilization of impaction grease on PVC filters, which will undergo endotoxin analysis, as there is potential for interference, particularly if high or low levels of endotoxin are anticipated. PMID:19437284

  11. Beneficial effect of human umbilical cord-derived mesenchymal stem cells on an endotoxin-induced rat model of preeclampsia

    PubMed Central

    FU, LIHUA; LIU, YONGJUN; ZHANG, DAN; XIE, JIANG; GUAN, HONGBO; SHANG, TAO

    2015-01-01

    Mesenchymal stem cells (MSCs), which exhibit the property of immune-modulation, have been shown to treat various diseases, including pulmonary hypertension. There is a functional similarity between the pulmonary circulation and the placenta, but it remains to be elucidated whether MSCs can be applied to treat endotoxin-induced hypertension during pregnancy; therefore, the aim of the present study was to investigate the therapeutic effect of a human umbilical cord-derived MSC infusion on endotoxin-induced hypertension during pregnancy. Rats were randomly divided into three groups (n=7 per group): Control, endotoxin-treated and endotoxin + MSCs. The model of preeclampsia (PE) was established via the intravenous injection of endotoxin. In the endotoxin + MSCs group, MSCs at 2×106 cells/rat were injected via the vena caudalis. The blood pressure, urine protein and number of white blood cells were measured. In addition, the protein expression levels of the pro-inflammatory cytokines interleukin (IL)-1? and tumor necrosis factor-? (TNF-?) and the anti-inflammatory cytokine IL-10 were examined by ELISA. The blood pressure, levels of urine protein and number of white blood cells in the endotoxin-treated group were significantly higher than those in the control group (P<0.05); however, this increase was significantly attenuated in the endotoxin + MSCs group (P<0.05). In addition, the application of MSCs significantly reduced the levels of pro-inflammatory TNF-? and IL-1? and increased the levels of anti-inflammatory IL-10 in the endotoxin-treated rats. In conclusion, umbilical cord-derived MSCs have a protective effect in an endotoxin-induced model of PE, and this effect is likely elicited through the suppression of inflammatory factors. Umbilical cord-derived MSC-based therapy may provide a potential therapeutic method for endotoxin-induced hypertension during pregnancy.

  12. Structure elucidation and biosynthesis gene cluster organization of the O-antigen of Escherichia coli O170.

    PubMed

    Shashkov, Alexander S; Wang, Tianwei; Perepelov, Andrei V; Weintraub, Andrej; Liu, Bin; Widmalm, Göran; Knirel, Yuriy A

    2015-11-19

    Enterotoxigenic Escherichia coli are causative agents of diarrhea in humans as well as animals, and E.coli O170 belongs to this virotype. Upon mild acid degradation of the lipopolysaccharide of E.coli O170, the branched O-polysaccharide chain was partially cleaved at ?-d-glactofuranosidic linkages to give multiple products, including a linear tetrasaccharide and oligomers thereof. Studies of the acid degradation products and O-deacylated lipopolysaccharide by 1D and 2D (1)H and (13)C NMR spectroscopy enabled elucidation of the following O-polysaccharide structure: Functions of genes in the O-antigen biosynthesis gene cluster were tentatively assigned and found to be in agreement with the O-polysaccharide structure. PMID:26382081

  13. Shotgun Analysis of Rough-Type Lipopolysaccharides Using Ultraviolet Photodissociation Mass Spectrometry.

    PubMed

    Klein, Dustin R; Holden, Dustin D; Brodbelt, Jennifer S

    2016-01-01

    Detailed structural characterization of intact rough-type lipopolysaccharides (R-LPS) was accomplished using a multi-stage mass spectrometry (MS(3)) strategy consisting of collision-induced dissociation (CID) followed by 193 ultraviolet photodissociation (UVPD) implemented on an Orbitrap Fusion mass spectrometer. Complex mixtures of R-LPS from either Escherichia coli or Salmonella enterica were directly infused into the mass spectrometer using static source nanoelectrospray ionization (nanoESI). An initial CID event performed on an R-LPS precursor produced spectra with abundant ions corresponding to the lipid A and core oligosaccharide (OS) substructures. Comparison of CID spectra of R-LPS ions with varying lipid A and core OS structures verifies that lipid A and core OS ions are consistently produced in high abundance. The resulting lipid A and core OS ions were subsequently activated by CID, high-energy collision-induced dissociation (HCD), or UVPD. For both the lipid A and core OS substructures, HCD and UVPD produced highly informative complementary spectra, with UVPD of the core OS producing an extensive array of cross-ring cleavage fragments. Successful discernment of E. coli R-LPS structures with isomeric core structures confirmed the degree to which subtle structural differences could be determined using this method. PMID:26616388

  14. Lipopolysaccharide induces recurrence of arthritis in rat joints previously injured by peptidoglycan-polysaccharide

    PubMed Central

    1987-01-01

    Rat ankle joints injected intraarticularly with 5 micrograms of group A streptococcal peptidoglycan-polysaccharide (PG-APS) developed an acute course of arthritis. Recurrence of arthritis was induced in 100% of these joints by intravenous injection of as little as 10 micrograms of Salmonella typhimurium lipopolysaccharide (LPS) 3 wk after intraarticular injection. This reaction was similar in athymic and euthymic rats. Buffalo rats were less susceptible than Lewis or Sprague- Dawley rats. Neisseria gonorrhoeae, Yersinia enterocolitica, and Escherichia coli LPS, and S. typhimurium Re mutant LPS, were also active. Re mutant LPS activity was greatly reduced by mixing with polymyxin B. E. coli lipid A was weakly active. An acute synovitis of much less incidence, severity, and duration was seen in contralateral joints injected initially with saline, and in ankle joints of naive, previously uninjected rats after intravenous LPS injection. The intravenous injection of the muramidase mutanolysin on day 0 or 7 after intraarticular PG-APS injection prevented LPS-induced recurrence of arthritis. These studies suggest that the phlogistic activities of lipid A and peptidoglycan might interact in an inflammatory disease process, and that LPS may play a role in recurrent episodes of rheumatoid arthritis or reactive arthritis. PMID:3295108

  15. Effects of Endotoxin and Psychological Stress on Redox Physiology, Immunity and Feather Corticosterone in Greenfinches

    PubMed Central

    Meitern, Richard; Sild, Elin; Lind, Mari-Ann; Männiste, Marju; Sepp, Tuul; Karu, Ulvi; Hõrak, Peeter

    2013-01-01

    Assessment of costs accompanying activation of immune system and related neuroendocrine pathways is essential for understanding the selective forces operating on these systems. Here we attempted to detect such costs in terms of disruption to redox balance and interference between different immune system components in captive wild-caught greenfinches (Carduelis chloris). Study birds were subjected to an endotoxin-induced inflammatory challenge and temporary exposure to a psychological stressor (an image of a predator) in a 2*2 factorial experiment. Injection of bacterial endotoxin resulted in up-regulation of two markers of antioxidant protection – erythrocyte glutathione, and plasma oxygen radical absorbance (OXY). These findings suggest that inflammatory responses alter redox homeostasis. However, no effect on markers of oxidative damage to proteins or DNA in erythrocytes could be detected. We found no evidence that the endotoxin injection interfered with antibody production against Brucella abortus antigen or the intensity of chronic coccidiosis. The hypothesis of within-immune system trade-offs as a cost of immunity was thus not supported in our model system. We showed for the first time that administration of endotoxin can reduce the level of corticosterone deposited into feathers. This finding suggests a down-regulation of the corticosterone secretion cascade due to an endotoxin-induced immune response, a phenomenon that has not been reported previously. Exposure to the predator image did not affect any of the measured physiological parameters. PMID:23805316

  16. Microwave radiation (2450 MHz) alters the endotoxin-induced hypothermic response of rats

    SciTech Connect

    Smialowicz, R.J.; Compton, K.L.; Riddle, M.M.; Rogers, R.R.; Brugnolotti, P.L.

    1980-01-01

    The parenteral administration of bacterial endotoxin to rats causes a hypothermia that is maximal after approximately 90 minutes. When endotoxin-injected rats were held in a controlled environment at 22 degree C and 50% relative humidity and exposed for 90 minutes to microwaves (2450 MHz, CW) at 1 mW/cm2, significant increases were observed in body temperature compared with endotoxin-treated, sham-irradiated rats. The magnitude of the response was related to power density (10 mW/cm2 greater than 5 mW/cm2 greater than 1 mW/cm2). Saline-injected rats exposed for 90 minutes at 5 mW/cm2 (specific absorption rate approximately 1.0 mW/g) showed no significant increase in body temperature compared with saline-injected, sham-irradiated rats. The hypothermia induced by endotoxin in rats was also found to be affected by ambient temperature alone. Increases in ambient temperature above 22 degree C in the absence of microwaves caused a concomitant increase in body temperature. This study reveals that subtle microwave heating is detectable in endotoxin-treated rats that have impaired thermoregulatory capability. These results indicate that the interpretation of microwave-induced biological effects observed in animals at comparable rates and levels of energy absorption should include a consideration of the thermogenic potential of microwave.

  17. Control of workers' exposure to airborne endotoxins and formaldehyde during the use of metalworking fluids.

    PubMed

    Linnainmaa, Markku; Kiviranta, Hannu; Laitinen, Juha; Laitinen, Sirpa

    2003-01-01

    The study evaluated the effects of triazine use and machine enclosure on workers' exposure to bacteria, endotoxins, and formaldehyde in the use of metalworking fluids (MWF). Concentrations of triazine and bacterial contaminants were monitored in bulk samples of MWF from two machines in one workplace. One of the machines was used normally; triazine was added to the other when needed. Air sampling was used to estimate workers' exposure to endotoxins at 18 workplaces near enclosed and open machines. Concentrations of triazine in MWF and formaldehyde in the air were measured. Some recirculating local exhaust ventilation systems were also tested. The endotoxin and bacteria concentrations in the biocide test of MWF rapidly increased when the biocide levels decreased below 500 ppm. Airborne concentrations of endotoxins were substantially lower near enclosed machines than near open ones. Concentrations of airborne formaldehyde were below the Finnish occupational exposure limit at the existing levels of triazine in MWF. Concentrations of triazine in MWF correlated well with those of formaldehyde in the air near the machines (correlation coefficient r=.69). The results showed that the triazine levels in MWF should continuously be kept high enough (>500 ppm) to prevent workers' exposure to endotoxins and bacteria. Overdosing with triazine, however, should be avoided, so that the levels of airborne formaldehyde remain low. Triazine levels in MWF can be followed by the method described in this article. Workers' exposure to contaminants of MWF can be reduced substantially by enclosing the machines and equipping them with local exhausts. PMID:12908865

  18. Circulating endotoxin and antiendotoxin antibodies during severe sepsis and septic shock.

    PubMed

    Maury, Eric; Blanchard, Hervé S; Chauvin, Pierre; Guglielminotti, Jean; Alzieu, Marc; Guidet, Bertrand; Offenstadt, Georges

    2003-06-01

    The presence of circulating endotoxin is common during sepsis but its prognostic value is poor. We hypothesized that this lack of correlation with outcome could be related in part to the presence of circulating antiendotoxin antibodies. In a 14-bed medical intensive care unit, in an 821-bed tertiary teaching hospital, we prospectively assessed endotoxin and antiendotoxin antibodies in patients with severe sepsis or septic shock. Blood samples for the determination of circulating endotoxin and antiendotoxin antibodies were drawn when severe sepsis or septic shock were diagnosed (day 0) and then on day 1, day 2, and day 4. Daily measurements of antiendotoxin antibodies did not discriminate survivors from nonsurvivors. No antibody depletion was observed. However, during follow-up, the antiendotoxin immunoglobulin (Ig)M antibody level increased among survivors but decreased among nonsurvivors (51.2 vs -44.8 MU/mL, P=007). Circulating endotoxin was detectable among 9 of 17 patients on inclusion but neither the basal value nor sequential measurements correlated with outcome. These results suggest that during severe sepsis and septic shock, circulating endotoxin is a poor prognostic marker whereas the detection of an increase in IgM antiendotoxin antibody levels could identify survivors. This increase in IgM antibody levels could be attributed to a reactivation of the immune system. PMID:12800122

  19. Lipopolysaccharide inhibits transforming growth factor-beta1-stimulated Smad6 expression by inducing phosphorylation of the linker region of Smad3 through a TLR4-IRAK1-ERK1/2 pathway.

    PubMed

    Kim, Eun-Ye; Kim, Byung-Chul

    2011-03-01

    Smad6, one of the inhibitory Smads, plays an important role in transforming growth factor-beta1 (TGF-?1)-mediated negative regulation of pro-inflammatory signaling. In this study, we found that bacterial endotoxin lipopolysaccharide (LPS) inhibits TGF-?1-induced expression of Smad6 in RAW264.7 cells. This repression was accompanied by increased Smad3 linker phosphorylation at Thr-179 and Ser-208 and was dependent on ERK1/2 activity via the TLR4-IRAK1-linked signaling cascade. The expression of a mutant Smad3, that lacks the phosphorylation sites in the linker regions, significantly reversed the inhibitory effect of LPS on TGF-?1-induced Smad6 expression and its anti-inflammatory capacity. Collectively, our findings show how LPS pro-inflammatory signal antagonizes the anti-inflammatory activity of TGF-?1. PMID:21295571

  20. Effect of endotoxin and platelet-activating factor on rat vascular permeability: role of vasoactive mediators.

    PubMed

    Balsa, D; Merlos, M; Giral, M; Ferrando, R; Garcia-Rafanell, J; Forn, J

    1997-09-01

    The contribution of several vasoactive mediators such as histamine, serotonin, bradykinin, arachidonic acid metabolites and PAF to vascular permeability changes was determined in a rat model of acute endotoxemia. Lipopolysaccharide (10-40 mg/kg, i.v.) from E. coli 0127:B8 (LPS) elicited an increase in Evans blue extravasation in trachea, thymus, seminal vesicle and stomach, whereas other organs remained unaffected. LPS (25 mg/kg)-induced extravasation was not inhibited by intravenous pretreatment with histamine (H1) antagonist mepyramine (5 mg/kg) or bradykinin (B2) antagonist HOE-140 (0.1 mg/kg), whereas other standard drugs selectively inhibited leakage in particular tissues, e.g. the cyclooxygenase inhibitor indomethacin (5 mg/kg) in trachea (78%) and seminal vesicle (64%), the serotonin and H1 antagonists cyproheptadine (2 mg/kg) in trachea (88%) and stomach (56%) and the dual cyclooxygenase/lipoxygenase inhibitor phenidone (10 mg/kg) in seminal vesicle (87%). PAF antagonists lexipafant and UR-12460 (10 mg/kg), but not apafant, potently inhibited extravasation in trachea (59, 84%) and seminal vesicle (81, 78%) and in stomach only UR-12460 (52%), whereas all of them were ineffective in thymus. When extravasation was induced by PAF (4 micrograms/kg) a low dose (0.1 mg/kg) of the three PAF antagonists strongly reduced extravasation in thymus and seminal vesicle, whereas lexipafant and UR-12460 did so in trachea (82, 100%) and only lexipafant in stomach (100%). Mepyramine, cyproheptadine, HOE-140 and indomethacin did not inhibit the effect of PAF, whereas phenidone inhibited it by 58% in trachea. These results suggest that most of the LPS-induced increase in vascular permeability is mediated by secondary vasoactive mediators among which PAF plays a pivotal role, although their relative contribution may vary from tissue to tissue. PMID:9302653

  1. Seasonal variation in airborne endotoxin levels in indoor environments with different micro-environmental factors in Seoul, South Korea.

    PubMed

    Hwang, Sung Ho; Park, Dong Jin; Park, Wha Me; Park, Dong Uk; Ahn, Jae Kyoung; Yoon, Chung Sik

    2016-02-01

    This study evaluated the variation over a year in airborne endotoxin levels in the indoor environment of five university laboratories in Seoul, South Korea, and examined the micro-environmental factors that influenced endotoxin levels. These included temperature, relative humidity, CO2, CO, illumination, and wind velocity. A total of 174 air samples were collected and analyzed using the kinetic limulus amebocyte lysate assay. Endotoxin levels ranged from <0.001 to 8.90EU/m(3), with an overall geometric mean of 0.240EU/m(3). Endotoxin levels showed significantly negative correlation with temperature (r=-0.529, p<0.001), CO2 (r=-0.213, p<0.001) and illumination (r=-0.538, p<0.001). Endotoxin levels tended to be higher in winter. Endotoxin levels in laboratories with rabbits were significantly higher than those of laboratories with mice. Multivariate regression analysis showed that the environmental factors affecting endotoxin levels were temperature (coefficient=-0.388, p<0.001) and illumination (coefficient=-0.370, p<0.001). Strategies aimed at reducing airborne endotoxin levels in the indoor environments may be most effective if they focus on illumination. PMID:26656510

  2. 40 CFR 180.1108 - Delta endotoxin of Bacillus thuringiensis variety San Diego encapsulated into killed Pseudomonas...

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 24 2011-07-01 2011-07-01 false Delta endotoxin of Bacillus... From Tolerances § 180.1108 Delta endotoxin of Bacillus thuringiensis variety San Diego encapsulated into killed Pseudomonas fluorescens; exemption from the requirement of a tolerance. The delta...

  3. 40 CFR 180.1108 - Delta endotoxin of Bacillus thuringiensis variety San Diego encapsulated into killed Pseudomonas...

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 25 2013-07-01 2013-07-01 false Delta endotoxin of Bacillus... From Tolerances § 180.1108 Delta endotoxin of Bacillus thuringiensis variety San Diego encapsulated into killed Pseudomonas fluorescens; exemption from the requirement of a tolerance. The delta...

  4. 40 CFR 180.1108 - Delta endotoxin of Bacillus thuringiensis variety San Diego encapsulated into killed Pseudomonas...

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 25 2012-07-01 2012-07-01 false Delta endotoxin of Bacillus... From Tolerances § 180.1108 Delta endotoxin of Bacillus thuringiensis variety San Diego encapsulated into killed Pseudomonas fluorescens; exemption from the requirement of a tolerance. The delta...

  5. 40 CFR 180.1108 - Delta endotoxin of Bacillus thuringiensis variety San Diego encapsulated into killed Pseudomonas...

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 24 2014-07-01 2014-07-01 false Delta endotoxin of Bacillus... From Tolerances § 180.1108 Delta endotoxin of Bacillus thuringiensis variety San Diego encapsulated into killed Pseudomonas fluorescens; exemption from the requirement of a tolerance. The delta...

  6. 40 CFR 180.1108 - Delta endotoxin of Bacillus thuringiensis variety San Diego encapsulated into killed Pseudomonas...

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 23 2010-07-01 2010-07-01 false Delta endotoxin of Bacillus... From Tolerances § 180.1108 Delta endotoxin of Bacillus thuringiensis variety San Diego encapsulated into killed Pseudomonas fluorescens; exemption from the requirement of a tolerance. The delta...

  7. Lipopolysaccharide induced conversion of recombinant prion protein.

    PubMed

    Saleem, Fozia; Bjorndahl, Trent C; Ladner, Carol L; Perez-Pineiro, Rolando; Ametaj, Burim N; Wishart, David S

    2014-01-01

    The conformational conversion of the cellular prion protein (PrP(C)) to the ?-rich infectious isoform PrP(Sc) is considered a critical and central feature in prion pathology. Although PrP(Sc) is the critical component of the infectious agent, as proposed in the "protein-only" prion hypothesis, cellular components have been identified as important cofactors in triggering and enhancing the conversion of PrP(C) to proteinase K resistant PrP(Sc). A number of in vitro systems using various chemical and/or physical agents such as guanidine hydrochloride, urea, SDS, high temperature, and low pH, have been developed that cause PrP(C) conversion, their amplification, and amyloid fibril formation often under non-physiological conditions. In our ongoing efforts to look for endogenous and exogenous chemical mediators that might initiate, influence, or result in the natural conversion of PrP(C) to PrP(Sc), we discovered that lipopolysaccharide (LPS), a component of gram-negative bacterial membranes interacts with recombinant prion proteins and induces conversion to an isoform richer in ? sheet at near physiological conditions as long as the LPS concentration remains above the critical micelle concentration (CMC). More significant was the LPS mediated conversion that was observed even at sub-molar ratios of LPS to recombinant ShPrP (90-232). PMID:24819168

  8. Lipopolysaccharide induced conversion of recombinant prion protein

    PubMed Central

    Saleem, Fozia; Bjorndahl, Trent C; Ladner, Carol L; Perez-Pineiro, Rolando; Ametaj, Burim N; Wishart, David S

    2014-01-01

    The conformational conversion of the cellular prion protein (PrPC) to the ?-rich infectious isoform PrPSc is considered a critical and central feature in prion pathology. Although PrPSc is the critical component of the infectious agent, as proposed in the “protein-only” prion hypothesis, cellular components have been identified as important cofactors in triggering and enhancing the conversion of PrPC to proteinase K resistant PrPSc. A number of in vitro systems using various chemical and/or physical agents such as guanidine hydrochloride, urea, SDS, high temperature, and low pH, have been developed that cause PrPC conversion, their amplification, and amyloid fibril formation often under non-physiological conditions. In our ongoing efforts to look for endogenous and exogenous chemical mediators that might initiate, influence, or result in the natural conversion of PrPC to PrPSc, we discovered that lipopolysaccharide (LPS), a component of gram-negative bacterial membranes interacts with recombinant prion proteins and induces conversion to an isoform richer in ? sheet at near physiological conditions as long as the LPS concentration remains above the critical micelle concentration (CMC). More significant was the LPS mediated conversion that was observed even at sub-molar ratios of LPS to recombinant ShPrP (90–232). PMID:24819168

  9. Structure and Effects of Cyanobacterial Lipopolysaccharides

    PubMed Central

    Durai, Prasannavenkatesh; Batool, Maria; Choi, Sangdun

    2015-01-01

    Lipopolysaccharide (LPS) is a component of the outer membrane of mainly Gram-negative bacteria and cyanobacteria. The LPS molecules from marine and terrestrial bacteria show structural variations, even among strains within the same species living in the same environment. Cyanobacterial LPS has a unique structure, since it lacks heptose and 3-deoxy-d-manno-octulosonic acid (also known as keto-deoxyoctulosonate (KDO)), which are present in the core region of common Gram-negative LPS. In addition, the cyanobacterial lipid A region lacks phosphates and contains odd-chain hydroxylated fatty acids. While the role of Gram-negative lipid A in the regulation of the innate immune response through Toll-like Receptor (TLR) 4 signaling is well characterized, the role of the structurally different cyanobacterial lipid A in TLR4 signaling is not well understood. The uncontrolled inflammatory response of TLR4 leads to autoimmune diseases such as sepsis, and thus the less virulent marine cyanobacterial LPS molecules can be effective to inhibit TLR4 signaling. This review highlights the structural comparison of LPS molecules from marine cyanobacteria and Gram-negative bacteria. We discuss the potential use of marine cyanobacterial LPS as a TLR4 antagonist, and the effects of cyanobacterial LPS on humans and marine organisms. PMID:26198237

  10. Lipopolysaccharides and plant responses to phytopathogenic bacteria.

    PubMed

    Newman, M A; von Roepenack, E; Daniels, M; Dow, M

    2000-01-01

    Abstract Treatment of the leaves of pepper (Capsicum annuum) cv. ECW10R with lipopolysaccharides (LPS) from both plant pathogenic and enteric bacteria alters several aspects of the plant response to subsequent inoculation with phytopathogenic xanthomonads. LPS pre-treatment prevents the hypersensitive reaction caused by strains of Xanthomonas campestris pv. vesicatoria carrying the avirulence gene avrBs1 (a gene-for-gene interaction) and by X. campestris pv. campestris (a non-host interaction). Associated with this effect are the earlier synthesis of feruloyl- and coumaroyl-tyramine, phenolic conjugates that are potentially antimicrobial, and alterations in the expression patterns of genes for some pathogenesis-related (PR) proteins. Similar effects on the timing of phenolic conjugate synthesis are also seen in the compatible interaction with X. campestris pv. vesicatoria, although the level of the response is lower. Recognition of LPS by plants may allow expression of resistance in the absence of catastrophic tissue damage. However phytopathogenic bacteria may have evolved mechanisms to suppress the effects of LPS (and of other non-specific bacterial elicitors) on plant cells. PMID:20572947

  11. Interaction of Campylobacter jejuni and Campylobacter coli with lectins and blood group antibodies.

    PubMed Central

    Wong, K H; Skelton, S K; Feeley, J C

    1985-01-01

    Lectins and blood group antibodies were used to probe the surface structures of Campylobacter jejuni and Campylobacter coli. Of the 29 strains tested, there were distinct reaction patterns. The lectin-reactive and blood group antibody-reactive sites on the bacterial surface were distinguishable from the heat-stable (lipopolysaccharide) antigenic determinants. The interactions were strain specific. The reactive sites were stable with respect to culture media and passage and may be useful as additional markers for strain characterization. PMID:2410445

  12. Quantitation of endotoxin in blood from patients with meningococcal disease using a limulus lysate test in combination with chromogenic substrate.

    PubMed

    Harthug, S; Bjorvatn, B; Osterud, B

    1983-01-01

    The levels of endotoxin in blood were determined using the Limulus lysate test in combination with a chromogenic substrate. Plasma was analyzed from four patients with fatal meningococcal septicaemia and from one patient who survived meningococcal meningitis. All septicaemia patients showed high levels of endotoxin in their blood during the early stage of their disease. In two of these patients, blood samples collected at intervals of two days revealed a gradual disappearance of measurable endotoxin from the circulation. The patient with meningitis had no clinical signs of circulatory deficiency or coagulopathy and was consistently negative for endotoxin using this test procedure. Pretreating the plasma with heat and alkali and combining the Limulus lysate test with a chromogenic substrate seem to provide a sensible method for the detection and quantitation of endotoxin in blood. PMID:6352508

  13. Diarrheagenic Escherichia coli

    PubMed Central

    Nataro, James P.; Kaper, James B.

    1998-01-01

    Escherichia coli is the predominant nonpathogenic facultative flora of the human intestine. Some E. coli strains, however, have developed the ability to cause disease of the gastrointestinal, urinary, or central nervous system in even the most robust human hosts. Diarrheagenic strains of E. coli can be divided into at least six different categories with corresponding distinct pathogenic schemes. Taken together, these organisms probably represent the most common cause of pediatric diarrhea worldwide. Several distinct clinical syndromes accompany infection with diarrheagenic E. coli categories, including traveler’s diarrhea (enterotoxigenic E. coli), hemorrhagic colitis and hemolytic-uremic syndrome (enterohemorrhagic E. coli), persistent diarrhea (enteroaggregative E. coli), and watery diarrhea of infants (enteropathogenic E. coli). This review discusses the current level of understanding of the pathogenesis of the diarrheagenic E. coli strains and describes how their pathogenic schemes underlie the clinical manifestations, diagnostic approach, and epidemiologic investigation of these important pathogens. PMID:9457432

  14. Inactivation of microorganisms and endotoxins by low temperature nitrogen gas plasma exposure.

    PubMed

    Shintani, Hideharu; Shimizu, Naohiro; Imanishi, Yuichiro; Sekiya, Takayuki; Tamazawa, Kahoru; Taniguchi, Akira; Kido, Nobuo

    2007-12-01

    The plasma of several different gases has shown a sporicidal activity. From these gases, nitrogen gas was most difficult to produce atomic nitrogen radicals. However, these radicals have a high energy, indicating that nitrogen gas plasma could be used to sterilize microorganisms and inactivate endotoxins. The sterilization mechanism of nitrogen gas plasma is the synergistic effect of a high rising-up voltage pulse, UV irradiation and atomic nitrogen radicals. Thus, the target cells were damaged by degradation, which resulted in death. The biological indicator (BI) used in this study was Geobacillus stearothermophilus ATCC 7953 at a population of 1 x 10(6) CFU/sheet. Sterility assurance was confirmed by using the BI. Moreover, endotoxins were successfully inactivated. More than 5 log reduction of endotoxins could be attained with 30 minutes of nitrogen gas plasma exposure. Material functionality influenced by nitrogen gas plasma presented a satisfactory result. No deterioration of polymers could be observed by nitrogen gas plasma exposure. PMID:18198719

  15. Personal Exposure to Particulate Matter and Endotoxin in California Dairy Workers

    NASA Astrophysics Data System (ADS)

    Garcia, Johnny

    The average number of cows per dairy has increased over the last thirty years, with little known about how this increase may impact occupational exposure. Thirteen California dairies and 226 workers participated in this study throughout the 2008 summer months. Particulate Matter (PM) and endotoxin concentrations were quantified using ambient area based and personal air samplers. Two size fractions were collected, Total Suspended Particulate matter (TSP) and PM 2.5. Differences across dairies were evaluated by placing area based integrated air samplers in established locations on the dairies, e.g. milking parlor, drylot corral, and freestall barns. The workers occupational exposure was quantified using personal air samplers. We analyzed concentrations along with the time workers spent conducting specific job tasks during their shift to identify high exposure job tasks. Biological and chemical analytical methods were employed to ascertain endotoxin concentrations in personal and area based air samples. Recombinant factor C assays (rFC) were used to analyze biologically active endotoxin and gas chromatography coupled with mass spectrometry in tandem (GC-MS/MS) was used to quantify total endotoxin. The PM2.5 concentrations ranged from 2-116 mug/m3 for ambient area concentration and 7-495 mug/m3 for personal concentrations while TSP concentrations ranged from 74-1690 mug/m3 for area ambient concentrations and 191-4950 mug/m3 for personal concentrations. Biologically active endotoxin concentrations in the TSP size fraction from ambient area based samples ranged from 11-2095 EU/m3 and 45-2061 EU/m3 for personal samples. Total endotoxin in the TSP size fraction ranged from 75-10,166 pmol/m3 for area based samples and 34-11,689 pmol/m3 for personal samples. Drylot corrals were found to have higher sample mean concentrations when compared to other locations on the dairies for PM and endotoxin. Re-bedding, of the freestalls, was found to consistently lead to higher personal sample mean concentrations when compared to other tasks performed on dairies for both endotoxin and PM. In mixed effect regression models, regional ambient concentrations of PM 2.5 helped account for variation in PM2.5 concentration outcomes. We found that while upwind and downwind mean concentrations were not significantly different, central mean concentrations were higher than upwind concentration. Variation in TSP levels was largely explained by dairy-level characteristics such as the age of the dairy and number of animals in the drylot corrals and freestall barns. The different locations within the dairy were found to differ in mean concentrations for TSP. Biologically active and total endotoxin concentration variation was explained by meteorological data, wind speed, relative humidity, and dairy waste management practices. Personal exposure levels where found to be higher than area based concentrations for PM and endotoxin. Endotoxin characteristics differed by particle size and location within the dairy. The chain length proportion for endotoxin in the PM 2.5 size fraction was dominated by C12 and C16 in the TSP size fraction.

  16. Intrauterine Endotoxin Administration Leads to White Matter Diffusivity Changes in Newborn Rabbits

    PubMed Central

    Saadani-Makki, Fadoua; Kannan, Sujatha; Makki, Malek; Muzik, Otto; Janisse, James; Romero, Roberto; Chugani, Diane

    2010-01-01

    Maternal intrauterine inflammation has been implicated in the development of periventricular leukomalacia and white matter injury in the neonate. We hypothesized that intrauterine endotoxin administration would lead to microstructural changes in the neonatal rabbit white matter in vivo that could be detected at birth using diffusion tensor magnetic resonance imaging (MRI). Term newborn rabbit kits (gestational age 31 days) born to dams exposed to saline or endotoxin in utero on gestational day 28 underwent diffusion tensor imaging, and brain sections were stained for microglia. Comparison between normal and endotoxin groups showed significant decreases in both fractional anisotropy and eigenvalue (e1) in all periventricular white matter regions that showed an increase in the number of activated microglial cells, indicating that after maternal inflammation, microglial infiltration may predominantly explain this change in diffusivity in the immediate neonatal period. Diffusion tensor imaging may be a clinically useful tool for detecting neuroinflammation induced by maternal infection in neonatal white matter. PMID:19745090

  17. Structure and gene cluster of the O-antigen of Escherichia coli O43.

    PubMed

    Perepelov, Andrei V; Guo, Xi; Filatov, Andrei V; Liu, Bin; Knirel, Yuriy A

    2015-10-30

    The O-polysaccharide (O-antigen) of Escherichia coli O43 was isolated from the lipopolysaccharide and studied by chemical methods, including sugar analyses, Smith degradation, and solvolysis with anhydrous trifluoroacetic acid, along with (1)H and (13)C NMR spectroscopy. The following structure of the pentasaccharide repeating unit of the O-polysaccharide was established: Functions of genes in the O-antigen gene cluster of E. coli O43 were assigned by a comparison with sequences in the available databases and found to be in agreement with the O-polysaccharide structure. PMID:26342864

  18. Workplace Determinants of Endotoxin Exposure in Dental Healthcare Facilities in South Africa

    PubMed Central

    Singh, Tanusha S.; Bello, Braimoh; Mabe, Onnicah D.; Renton, Kevin; Jeebhay, Mohamed F.

    2010-01-01

    Objectives: Aerosols generated during dental procedures have been reported to contain endotoxin as a result of bacterial contamination of dental unit water lines. This study investigated the determinants of airborne endotoxin exposure in dental healthcare settings. Methods: The study population included dental personnel (n?=?454) from five academic dental institutions in South Africa. Personal air samples (n?=?413) in various dental jobs and water samples (n?=?403) from dental handpieces and basin taps were collected. The chromogenic-1000 limulus amebocyte lysate assay was used to determine endotoxin levels. Exposure metrics were developed on the basis of individually measured exposures and average levels within each job category. Analysis of variance and multivariate linear regression models were constructed to ascertain the determinants of exposure in the dental group. Results: There was a 2-fold variation in personal airborne endotoxin from the least exposed (administration) to the most exposed (laboratory) jobs (geometric mean levels: 2.38 versus 5.63 EU m?3). Three percent of personal samples were above DECOS recommended exposure limit (50 EU m?3). In the univariate linear models, the age of the dental units explained the most variability observed in the personal air samples (R2?=?0.20, P?endotoxin levels in water, job category (staff versus students), dental unit model type and age of dental unit. Conclusions: Apart from job type, dental unit characteristics are important predictors of airborne endotoxin levels in this setting. PMID:20044586

  19. Cotton dust, endotoxin and cancer mortality among the Shanghai textile workers cohort: a 30-year analysis

    PubMed Central

    Fang, S C; Mehta, A J; Hang, J Q; Eisen, E A; Dai, H L; Zhang, H X; Su, L; Christiani, D C

    2013-01-01

    Background Although occupational exposure to cotton dust and endotoxin is associated with adverse respiratory health, associations with cancer are unclear. We investigated cancer mortality in relation to cotton dust and endotoxin exposure in the Shanghai textile workers cohort. Methods We followed 444 cotton textile and a reference group of 467 unexposed silk workers for 30 years (26 777 person-years). HRs for all cancers combined (with and without lung cancer) and gastrointestinal cancer were estimated in Cox regression models as functions of cotton textile work and categories of cumulative exposure (low, medium, high), after adjustment for covariates including pack-years smoked. Different lag years accounted for disease latency. Results Risks of mortality from gastrointestinal cancers and all cancers combined, with the exclusion of lung cancer, were increased in cotton workers relative to silk workers. When stratified by category of cumulative cotton exposure, in general, risks were greatest for 20-year lagged medium exposure (all cancers HR=2.7 (95% CI 1.4 to 5.2); cancer excluding lung cancer HR=3.4 (1.7–7.0); gastrointestinal cancer HR=4.1 (1.8–9.7)). With the exclusion of lung cancer, risks of cancer were more pronounced. When stratified by category of cumulative endotoxin exposure, consistent associations were not observed for all cancers combined. However, excluding lung cancer, medium endotoxin exposure was associated with all cancers and gastrointestinal cancer in almost all lag models. Conclusions Cotton dust may be associated with cancer mortality, especially gastrointestinal cancer, and endotoxin may play a causative role. Findings also indirectly support a protective effect of endotoxin on lung cancer. PMID:23828454

  20. Curcumin Analog L48H37 Prevents Lipopolysaccharide-Induced TLR4 Signaling Pathway Activation and Sepsis via Targeting MD2.

    PubMed

    Wang, Yi; Shan, Xiaoou; Dai, Yuanrong; Jiang, Lili; Chen, Gaozhi; Zhang, Yali; Wang, Zhe; Dong, Lili; Wu, Jianzhang; Guo, Guilong; Liang, Guang

    2015-06-01

    Endotoxin-induced acute inflammatory diseases such as sepsis, mediated by excessive production of various proinflammatory cytokines, remain the leading cause of mortality in critically ill patients. Lipopolysaccharide (LPS), the characteristic endotoxin found in the outer membrane of Gram-negative bacteria, can induce the innate immunity system and through the myeloid differentiation protein 2 (MD2) and Toll-like receptor 4 (TLR4) complex, increase the production of inflammatory mediators. Our previous studies have found that a curcumin analog, L48H37 [1-ethyl-3,5-bis(3,4,5-trimethoxybenzylidene)piperidin-4-one], was able to inhibit LPS-induced inflammation, particularly tumor necrosis factor ? and interleukin 6 production and gene expression in mouse macrophages. In this study, a series of biochemical experiments demonstrate L48H37 specifically targets MD2 and inhibits the interaction and signaling transduction of LPS-TLR4/MD2. L48H37 binds to the hydrophobic region of MD2 pocket and forms hydrogen bond interactions with Arg(90) and Tyr(102). Subsequently, L48H37 was shown to suppress LPS-induced mitogen-activated protein kinase phosphorylation and nuclear factor ?B activation in macrophages; it also dose dependently inhibits the cytokine expression in macrophages and human peripheral blood mononuclear cells stimulated by LPS. In LPS-induced septic mice, both pretreatment and treatment with L48H37 significantly improved survival and protected lung injury. Taken together, this work identified a new MD2 specific inhibitor, L48H37, as a potential candidate in the treatment of sepsis. PMID:25862641

  1. Concentration Dependent Influence of Lipopolysaccharides on Separation of Hoof Explants and Supernatant Lactic Acid Concentration in an Ex Vivo/In Vitro Laminitis Model

    PubMed Central

    Reisinger, Nicole; Schaumberger, Simone; Nagl, Veronika; Hessenberger, Sabine; Schatzmayr, Gerd

    2015-01-01

    Laminitis is one of the most common diseases in horses. It is not only painful for the animal, but also has a significant financial impact on the equine industry. This multifactorial disease affects the connective tissue of the hoof. However, the pathogenesis of laminitis is still not fully understood. Endotoxins, also known as lipopolysaccharides (LPS), and bacterial exotoxins seem to play an important role during the development of laminitis. The aim of our study was to investigate the effect of increasing LPS concentrations (0, 2.5, 5, 10, and 100 ?g/mL) on cell viability of isolated epidermal and dermal hoof cells as well as on the tissue integrity of hoof explants. Furthermore, glucose, acetic acid, lactic acid, and propionic acid concentrations in explant supernatants were measured to evaluate the energy metabolism in the hoof tissue. LPS did not exhibit cytotoxic effects on epidermal or dermal cells. Force required to separate LPS treated hoof explants decreased in a concentration dependent manner. Specifically, explants incubated with 10 and 100 ?g/mL needed significantly less force to separate compared to control explants. Lactic acid concentrations were significantly decreased in explants incubated with 5, 10, or 100 ?g/mL LPS, while glucose, acetic acid and propionic acid concentrations were unaffected by LPS treatment. Our study indicates that LPS has no cytotoxic effect on epidermal and dermal cells isolated from hoof tissue, but impairs integrity of hoof explants. In addition, LPS led to an alteration of the lactic acid production in the lamellar tissue. Since our data highlight that LPS can affect the integrity of the equine hoof tissue in vitro, endotoxins should be further explored for their contribution to facilitate the development of laminitis. PMID:26599864

  2. Predictors of coarse particulate matter and associated endotoxin concentrations in residential environments

    NASA Astrophysics Data System (ADS)

    Bari, Md. Aynul; MacNeill, Morgan; Kindzierski, Warren B.; Wallace, Lance; Héroux, Marie-Ève; Wheeler, Amanda J.

    2014-08-01

    Exposure to coarse particulate matter (PM), i.e., particles with an aerodynamic diameter between 2.5 and 10 ?m (PM10-2.5), is of increasing interest due to the potential for health effects including asthma, allergy and respiratory symptoms. Limited information is available on indoor and outdoor coarse PM and associated endotoxin exposures. Seven consecutive 24-h samples of indoor and outdoor coarse PM were collected during winter and summer 2010 using Harvard Coarse Impactors in a total of 74 Edmonton homes where no reported smoking took place. Coarse PM filters were subsequently analyzed for endotoxin content. Data were also collected on indoor and outdoor temperature, relative humidity, air exchange rate, housing characteristics and occupants' activities. During winter, outdoor concentrations of coarse PM (median = 6.7 ?g/m3, interquartile range, IQR = 3.4-12 ?g/m3) were found to be higher than indoor concentrations (median 3.4 ?g/m3, IQR = 1.6-5.7 ?g/m3); while summer levels of indoor and outdoor concentrations were similar (median 4.5 ?g/m3, IQR = 2.3-6.8 ?g/m3, and median 4.7 ?g/m3, IQR = 2.1-7.9 ?g/m3, respectively). Similar predictors were identified for indoor coarse PM in both seasons and included corresponding outdoor coarse PM concentrations, whether vacuuming, sweeping or dusting was performed during the sampling period, and number of occupants in the home. Winter indoor coarse PM predictors also included the number of dogs and indoor endotoxin concentrations. Summer median endotoxin concentrations (indoor: 0.41 EU/m3, outdoor: 0.64 EU/m3) were 4-fold higher than winter concentrations (indoor: 0.12 EU/m3, outdoor: 0.16 EU/m3). Other than outdoor endotoxin concentrations, indoor endotoxin concentration predictors for both seasons were different. Winter endotoxin predictors also included presence of furry pets and whether the vacuum had a high efficiency particulate air (HEPA) filter. Summer endotoxin predictors were problems with mice in the previous 12 months and mean indoor relative humidity levels.

  3. Phase Variation in Helicobacter pylori Lipopolysaccharide

    PubMed Central

    Appelmelk, B. J.; Shiberu, B.; Trinks, C.; Tapsi, N.; Zheng, P. Y.; Verboom, T.; Maaskant, J.; Hokke, C. H.; Schiphorst, W. E. C. M.; Blanchard, D.; Simoons-Smit, I. M.; van den Eijnden, D. H.; Vandenbroucke-Grauls, C. M. J. E.

    1998-01-01

    Helicobacter pylori NCTC 11637 lipopolysaccharide (LPS) expresses the human blood group antigen Lewis x (Lex) in a polymeric form. Lex is ?-d-galactose-(1-4)-[?-l-fucose-(1-3)]-?-d-acetylglucosamine. Schematically the LPS structure is (Lex)n-core-lipid A. In this report, we show that Lex expression is not a stable trait but that LPS displays a high frequency (0.2 to 0.5%) of phase variation, resulting in the presence of several LPS variants in one bacterial cell population. One type of phase variation implied the loss of ?1,3-linked fucose, resulting in variants that expressed nonsubstituted polylactosamines (also called the i antigen), i.e., Lex minus fucose; LPS: (lactosamine)n-core-lipid A. The switch of Lex to i antigen was reversible. A second group of variants arose by loss of polymeric main chain which resulted in expression of monomeric Ley; LPS: (Ley)-core-lipid A. A third group of variants arose by acquisition of ?1,2-linked fucose which hence expressed Lex plus Ley; LPS: (Ley)(Lex)n-core-lipid A. The second and third group of variants switched back to the parental phenotype [(Lex)n-core-lipid A] in lower frequencies. Part of the variation can be ascribed to altered expression levels of glycosyltransferase levels as assessed by assaying the activities of galactosyl-, fucosyl-, and N-acetylglucosaminyltransferases. Clearly phase variation increases the heterogeneity of H. pylori, and this process may be involved in generating the very closely related yet genetically slightly different strains that have been isolated from one patient. PMID:9423841

  4. Lipopolysaccharide (LPS) stimulation of fungal secondary metabolism

    PubMed Central

    Khalil, Zeinab G.; Kalansuriya, Pabasara; Capon, Robert J.

    2014-01-01

    We report on a preliminary investigation of the use the Gram-negative bacterial cell wall constituent lipopolysaccharide (LPS) as a natural chemical cue to stimulate and alter the expression of fungal secondary metabolism. Integrated high-throughput micro-cultivation and micro-analysis methods determined that 6 of 40 (15%) of fungi tested responded to an optimal exposure to LPS (0.6 ng/mL) by activating, enhancing or accelerating secondary metabolite production. To explore the possible mechanisms behind this effect, we employed light and fluorescent microscopy in conjunction with a nitric oxide (NO)-sensitive fluorescent dye and an NO scavenger to provide evidence that LPS stimulation of fungal secondary metabolism coincided with LPS activation of NO. Several case studies demonstrated that LPS stimulation can be scaled from single microplate well (1.5 mL) to preparative (>400 mL) scale cultures. For example, LPS treatment of Penicillium sp. (ACM-4616) enhanced pseurotin A and activated pseurotin A1 and pseurotin A2 biosynthesis, whereas LPS treatment of Aspergillus sp. (CMB-M81F) substantially accelerated and enhanced the biosynthesis of shornephine A and a series of biosynthetically related ardeemins and activated production of neoasterriquinone. As an indication of broader potential, we provide evidence that cultures of Penicillium sp. (CMB-TF0411), Aspergillus niger (ACM-4993F), Rhizopus oryzae (ACM-165F) and Thanatephorus cucumeris (ACM-194F) were responsive to LPS stimulation, the latter two examples being particular noteworthy as neither are known to produce secondary metabolites. Our results encourage the view that LPS stimulation can be used as a valuable tool to expand the molecular discovery potential of fungal strains that either have been exhaustively studied by or are unresponsive to traditional culture methodology. PMID:25379339

  5. Genetics of lipopolysaccharide biosynthesis in enteric bacteria.

    PubMed Central

    Schnaitman, C A; Klena, J D

    1993-01-01

    From a historical perspective, the study of both the biochemistry and the genetics of lipopolysaccharide (LPS) synthesis began with the enteric bacteria. These organisms have again come to the forefront as the blocks of genes involved in LPS synthesis have been sequenced and analyzed. A number of new and unanticipated genes were found in these clusters, indicating a complexity of the biochemical pathways which was not predicted from the older studies. One of the most dramatic areas of LPS research has been the elucidation of the lipid A biosynthetic pathway. Four of the genes in this pathway have now been identified and sequenced, and three of them are located in a complex operon which also contains genes involved in DNA and phospholipid synthesis. The rfa gene cluster, which contains many of the genes for LPS core synthesis, includes at least 17 genes. One of the remarkable findings in this cluster is a group of several genes which appear to be involved in the synthesis of alternate rough core species which are modified so that they cannot be acceptors for O-specific polysaccharides. The rfb gene clusters which encode O-antigen synthesis have been sequenced from a number of serotypes and exhibit the genetic polymorphism anticipated on the basis of the chemical complexity of the O antigens. These clusters appear to have originated by the exchange of blocks of genes among ancestral organisms. Among the large number of LPS genes which have now been sequenced from these rfa and rfb clusters, there are none which encode proteins that appear to be secreted across the cytoplasmic membrane and surprisingly few which encode integral membrane proteins or proteins with extensive hydrophobic domains. These data, together with sequence comparison and complementation experiments across strain and species lines, suggest that the LPS biosynthetic enzymes may be organized into clusters on the inner surface of the cytoplasmic membrane which are organized around a few key membrane proteins. PMID:7504166

  6. Lipopolysaccharide (LPS) stimulation of fungal secondary metabolism.

    PubMed

    Khalil, Zeinab G; Kalansuriya, Pabasara; Capon, Robert J

    2014-07-01

    We report on a preliminary investigation of the use the Gram-negative bacterial cell wall constituent lipopolysaccharide (LPS) as a natural chemical cue to stimulate and alter the expression of fungal secondary metabolism. Integrated high-throughput micro-cultivation and micro-analysis methods determined that 6 of 40 (15%) of fungi tested responded to an optimal exposure to LPS (0.6 ng/mL) by activating, enhancing or accelerating secondary metabolite production. To explore the possible mechanisms behind this effect, we employed light and fluorescent microscopy in conjunction with a nitric oxide (NO)-sensitive fluorescent dye and an NO scavenger to provide evidence that LPS stimulation of fungal secondary metabolism coincided with LPS activation of NO. Several case studies demonstrated that LPS stimulation can be scaled from single microplate well (1.5 mL) to preparative (>400 mL) scale cultures. For example, LPS treatment of Penicillium sp. (ACM-4616) enhanced pseurotin A and activated pseurotin A1 and pseurotin A2 biosynthesis, whereas LPS treatment of Aspergillus sp. (CMB-M81F) substantially accelerated and enhanced the biosynthesis of shornephine A and a series of biosynthetically related ardeemins and activated production of neoasterriquinone. As an indication of broader potential, we provide evidence that cultures of Penicillium sp. (CMB-TF0411), Aspergillus niger (ACM-4993F), Rhizopus oryzae (ACM-165F) and Thanatephorus cucumeris (ACM-194F) were responsive to LPS stimulation, the latter two examples being particular noteworthy as neither are known to produce secondary metabolites. Our results encourage the view that LPS stimulation can be used as a valuable tool to expand the molecular discovery potential of fungal strains that either have been exhaustively studied by or are unresponsive to traditional culture methodology. PMID:25379339

  7. Prolonged exposure of rat aorta to low levels of endotoxin in vitro results in impaired contractility. Association with vascular cytokine release.

    PubMed Central

    McKenna, T M

    1990-01-01

    Treatment of volunteers or animals with endotoxin in vivo results in reduced vascular reactivity to catecholamines. Endotoxin also causes liberation of the vasoactive cytokines interleukin-1 (IL-1) and tumor necrosis factor (TNF) from vascular smooth muscle and endothelial cells in culture. This study tested whether defects in contractility could be induced in isolated vascular tissue by prolonged exposure to endotoxin (1-100 ng/ml) in vitro, and whether IL-1 and TNF release by blood vessels is altered during the establishment of endotoxin induced contractile dysfunction. A concentration of endotoxin as low as 1 ng/ml suppressed contractions to norepinephrine (NE) and KCl; aortic sensitivity to NE also decreased. The presence of serum constituents or an intact endothelium were not necessary for endotoxin-induced vascular suppression. Aortas incubated with endotoxin liberated IL-1 and TNF in a dose-dependent fashion. The addition of dexamethasone or indomethacin during the incubations generally suppressed release of the cytokines and improved tissue reactivity to NE. The endotoxin-induced diminished vascular contraction and augmented IL-1 and TNF liberation required de novo protein synthesis; tissue incubated with endotoxin plus actinomycin D was completely shielded from the influence of endotoxin on vascular reactivity to NE. The association between endotoxin-induced vascular cytokine release and diminished contraction suggests a possible role for cytokines derived from the vasculature in the regulation of contractile function. Images PMID:2365814

  8. E. Coli Infections

    MedlinePLUS

    ... adults with weak immune systems. You can get E. coli infections by eating foods containing the bacteria. Symptoms of ... pool contaminated with human waste. Most cases of E. coli infection get better without treatment in 5 to 10 ...

  9. Induction of tolerance in mice and rats to the effect of endotoxin to decrease the hepatic microsomal mixed-function oxidase system. Evidence for a possible macrophage-derived factor in the endotoxin effect.

    PubMed

    Williams, J F

    1985-01-01

    Daily administration of low, non-lethal doses of bacterial endotoxin to mice and rats has been shown to induce tolerance to the effect of an acute challenge dose of endotoxin to decrease the hepatic microsomal drug metabolizing activity, the level of cytochrome P-450, and to increase heme oxygenase activity. The serum collected at various times after injection of endotoxin into control animals when injected into untreated animals markedly depressed aniline hydroxylase activity, ethylmorphine N-demethylase activity, and the level of cytochrome P-450. Tolerant animals were not affected by the post-endotoxin serum injection, suggesting the decreased activity caused by the serum in untreated animals was probably due to endotoxin contained in the serum. Injection of tolerant mice and rats with supernatant medium obtained from cultures of peritoneal macrophages incubated with 100 micrograms/ml of endotoxin caused a loss of hepatic microsomal drug-metabolizing activity, and a decrease in the level of cytochrome P-450. These results suggest that peritoneal macrophages release a factor in response to endotoxin that mediates the decreased hepatic mixed-function oxidase activity. PMID:3840129

  10. Monitoring total endotoxin and (1 --> 3)-beta-D-glucan at the air exhaust of concentrated animal feeding operations.

    PubMed

    Yang, Xufei; Wang, Xinlei; Zhang, Yuanhui; Lee, Jongmin; Su, Jingwei; Gates, Richard S

    2013-10-01

    Mitigation of bioaerosol emissions from concentrated animal feeding operations (CAFOs) demands knowledge of bioaerosol concentrations feeding into an end-of-pipe air treatment process. The aim of this preliminary study was to measure total endotoxin and (1 --> 3)-beta-glucan concentrations at the air exhaust of 18 commercial CAFOs and to examine their variability with animal operation type (swine farrowing, swine gestation, swine weaning, swine finishing, manure belt laying hen, and tom turkey) and season (cold, mild, and hot). The measured airborne concentrations of total endotoxin ranged from 98 to 23,157 endotoxin units (EU)/m3, and the airborne concentrations of total (1 --> 3)-beta-D-glucan ranged from 2.4 to 537.9 ng/m3. Animal operation type in this study had a significant effect on airborne concentrations of total endotoxin and (1 --> 3)-beta-D-glucan but no significant effect on their concentrations in total suspended particulate (TSP). Both endotoxin and (1 --> 3)-beta-D-glucan attained their highest airborne concentrations in visited tom turkey buildings. Comparatively, season had no significant effect on airborne concentrations of total endotoxin or (1 --> 3)-beta-D-glucan. Endotoxin and (1 --> 3)-beta-glucan concentrations in TSP dust appeared to increase as the weather became warmer, and this seasonal effect was significant in swine buildings. Elevated indoor temperatures in the hot season were considered to facilitate the growth and propagation of bacteria and fungi, thus leading to higher biocomponent concentrations in TSP. PMID:24282971

  11. Endotoxin-like effects in acute phase response to Trypanosoma brucei brucei infection are not due to gastrointestinal leakage.

    PubMed

    Ngure, R M; Eckersall, P; Burke, J; Karori, S M; Mwangi, W W; Wachira, F N; Maathai, R; Murray, M

    2009-12-01

    Trypanosomosis is mainly an immunological and inflammatory response mediated by increased levels of pro-inflammatory cytokines. Evidence suggests that pathological changes produced during infection with trypanosomes could be initiated by nonspecific endotoxin-like substances in trypanosomes and/or Gram-negative secondary bacterial infection. Studies in trypanosome-infected rats indicate damage to the gastrointestinal tract (GIT) accompanied by increased leakage of the GIT mucosa. The current study was carried out to determine the in vivo response to endotoxin-like substances of Trypanosoma brucei brucei. To this purpose we neutralized the entrance of endotoxin through the GIT using polymyxin-B treatment and monitored the plasma concentration of the acute phase proteins SAP and Hp. The results in this study, where infection was performed in the presence of oral antibiotic that is not absorbed from GIT and which binds to and inactivates endotoxin, show that the elevated plasma levels of endotoxin-like activity and the resulting acute phase response indicated by an increase in levels of Hp and SAP, are due to trypanosome infection. Results obtained in the present study indicate that GIT is not the major source of elevated plasma endotoxin-like activity levels and the observed acute phase response was due to an increase in the levels of acute phase proteins SAP and haptoglobin. Therefore trypanosomes are responsible for the elevated plasma endotoxin-like activity levels and the subsequent systemic acute phase response in the host. PMID:19567273

  12. Autotaxin and Endotoxin-Induced Acute Lung Injury

    PubMed Central

    Oikonomou, Nikos; Katsifa, Aggeliki; Prestwich, Glenn D.; Kaffe, Eleanna; Aidinis, Vassilis

    2015-01-01

    Acute Lung Injury (ALI) is a life-threatening, diffuse heterogeneous lung injury characterized by acute onset, pulmonary edema and respiratory failure. Lipopolysaccharide (LPS) is a common cause of both direct and indirect lung injury and when administered to a mouse induces a lung phenotype exhibiting some of the clinical characteristics of human ALI. Here, we report that LPS inhalation in mice results in increased bronchoalveolar lavage fluid (BALF) levels of Autotaxin (ATX, Enpp2), a lysophospholipase D largely responsible for the conversion of lysophosphatidylcholine (LPC) to lysophosphatidic acid (LPA) in biological fluids and chronically inflamed sites. In agreement, gradual increases were also detected in BALF LPA levels, following inflammation and pulmonary edema. However, genetic or pharmacologic targeting of ATX had minor effects in ALI severity, suggesting no major involvement of the ATX/LPA axis in acute inflammation. Moreover, systemic, chronic exposure to increased ATX/LPA levels was shown to predispose to and/or to promote acute inflammation and ALI unlike chronic inflammatory pathophysiological situations, further suggesting a differential involvement of the ATX/LPA axis in acute versus chronic pulmonary inflammation. PMID:26196781

  13. Apocynin ameliorates endotoxin-induced acute lung injury in rats.

    PubMed

    Abdelmageed, Marwa E; El-Awady, Mohammed S; Suddek, Ghada M

    2016-01-01

    Acute lung injury (ALI) is a serious clinical syndrome with a high rate of mortality. In this study, the effects of apocynin, a NADPH-oxidase (NOX) inhibitor on lipopolysaccharide (LPS)-induced ALI in rats were investigated. Male Sprague-Dawley rats were treated with apocynin (10mg/kg) intraperitoneally (i.p.) 1h before LPS injection (10mg/kg, i.p.). The results revealed that apocynin attenuated LPS-induced ALI as it decreased total protein content, lactate dehydrogenase (LDH) activity and the accumulation of the inflammatory cells in the bronchoalveolar lavage fluid (BALF), In addition, apocynin significantly increased superoxide dismutase (SOD) and reduced glutathione (GSH) activities with significant decrease in the lung malondialdehyde (MDA) content as compared to LPS group in lung tissue and decreased pulmonary artery contraction induced by LPS. It also upregulated mRNA expression of inhibitory protein kappaB-alpha (NF?Bia) and downregulated mRNA expression of Toll-Like receptor 4 (TLR4) and decreased inflammation observed in lung tissues. Collectively, these results demonstrate the protective effects of apocynin against the LPS-induced ALI in rats through its antioxidant and antiinflammatory effect that may be attributed to the decrease in mRNA expression of TLR4 and increasing that of NF?Bia. PMID:26687059

  14. Performance of electrostatic dust collectors (EDCs) for endotoxin assessment in homes: Effect of mailing, placement, heating, and electrostatic charge.

    PubMed

    Kilburg-Basnyat, Brita; Metwali, Nervana; Thorne, Peter S

    2016-02-01

    Electrostatic Dust Collectors (EDCs) are in use for passive sampling of bioaerosols, but particular aspects of their performance have not yet been evaluated. This study investigated the effect of mailing EDCs on endotoxin loading and the effect of EDC deployment in front of, and away from, heated ventilation on endotoxin sampling. Endotoxin sampling efficiency of heated and unheated EDC cloths was also evaluated. Cross-country express mailing of dust-spiked EDCs yielded no significant changes in endotoxin concentrations compared to dust-only samples for both high-spiked EDCs (p = 0.30) and low-spiked EDCs (p = 0.36). EDCs were also deployed in 20 identical apartments with one EDC placed in front of the univent heater in each apartment and contemporaneous EDC placed on the built-in bookshelf in each apartment. The endotoxin concentrations were significantly different (p = 0.049) indicating that the placement of EDC does impact endotoxin sampling. Heated and unheated EDCs were deployed for 7 days in pairs in farm homes. There was a significant difference between endotoxin concentrations (p = 0.027) indicating that heating EDCs may diminish their electrostatic capabilities and impact endotoxin sampling. The last study investigated the electrostatic charge of 12 heated and 12 unheated EDC cloths. There was a significant difference in charge (p = 0.009) which suggests that heating EDC cloths may make them less effective for sampling. In conclusion, EDCs can be mailed to and from deployment sites, EDC placement in relationship to ventilation is crucial, and heating EDCs reduces their electrostatic charge which may diminish their endotoxin sampling capabilities. PMID:26325020

  15. Year-long assessment of airborne endotoxin at a concentrated dairy operation

    Technology Transfer Automated Retrieval System (TEKTRAN)

    With the increasing prevalence of concentrated animal feeding operations (CAFOs), concern over bioaerosols drifting in downwind plumes is gaining attention as they may cause health effects in humans and livestock. In this study, we monitored total airborne endotoxins at upwind and downwind locations...

  16. Concentrations of airborne endotoxin and microorganisms at a 10,000 cow open-freestall dairy

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Confined animal production systems produce elevated bioaerosol concentrations, which are a potential respiratory health risk to individuals on site and downwind. In this study, airborne endotoxin and microorganisms were collected during the spring, summer, and fall at a large open-freestall dairy i...

  17. Mineralization of the Bacillus thuringiensis Cry1Ac endotoxin in soil

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Despite a number of studies describing the fate of Bacillus thuringiensis insecticidal endotoxins in soil have been conducted in the past decade, conflicting information on persistence of this class of insecticidal toxins exists. In the present experiment, 14C from glucose was incorporated into the ...

  18. Yeast cell wall supplementation alters the metabolic responses of crossbred heifers to an endotoxin challenge

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This study examined the effect of feeding yeast cell wall (YCW) products on the metabolic responses of newly-received heifers to endotoxin challenge. Heifers (n = 24; 219 ± 2.4 kg) were separated into treatment groups receiving a Control diet (n = 8), YCW-A (2.5 grams/heifer/d; n = 8) or YCW-C (2.5 ...

  19. Chronic endotoxin exposure produces airflow obstruction and lung dendritic cell expansion.

    PubMed

    Lai, Peggy S; Fresco, Jennifer M; Pinilla, Miguel A; Macias, Alvaro A; Brown, Ronald D; Englert, Joshua A; Hofmann, Oliver; Lederer, James A; Hide, Winston; Christiani, David C; Cernadas, Manuela; Baron, Rebecca M

    2012-08-01

    Little is known about the mechanisms of persistent airflow obstruction that result from chronic occupational endotoxin exposure. We sought to analyze the inflammatory response underlying persistent airflow obstruction as a result of chronic occupational endotoxin exposure. We developed a murine model of daily inhaled endotoxin for periods of 5 days to 8 weeks. We analyzed physiologic lung dysfunction, lung histology, bronchoalveolar lavage fluid and total lung homogenate inflammatory cell and cytokine profiles, and pulmonary gene expression profiles. We observed an increase in airway hyperresponsiveness as a result of chronic endotoxin exposure. After 8 weeks, the mice exhibited an increase in bronchoalveolar lavage and lung neutrophils that correlated with an increase in proinflammatory cytokines. Detailed analyses of inflammatory cell subsets revealed an expansion of dendritic cells (DCs), and in particular, proinflammatory DCs, with a reduced percentage of macrophages. Gene expression profiling revealed the up-regulation of a panel of genes that was consistent with DC recruitment, and lung histology revealed an accumulation of DCs in inflammatory aggregates around the airways in 8-week-exposed animals. Repeated, low-dose LPS inhalation, which mirrors occupational exposure, resulted in airway hyperresponsiveness, associated with a failure to resolve the proinflammatory response, an inverted macrophage to DC ratio, and a significant rise in the inflammatory DC population. These findings point to a novel underlying mechanism of airflow obstruction as a result of occupational LPS exposure, and suggest molecular and cellular targets for therapeutic development. PMID:22517795

  20. The influence of temperament, transportation stress, and endotoxin challenge on body composition traits in Brahman bulls

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This study was designed to determine the influence of temperament of bulls on ultrasound body composition traits in response to transportation and an endotoxin challenge. Purebred Brahman bulls were selected from a pool of 60 bulls based on temperament scores measured at weaning (n=8 each: calm, int...

  1. OCCURRENCE OF ANTIBIOTIC RESISTANT BACTERIA AND ENDOTOXIN ASSOCIATED WITH THE LAND APPLICATION OF BIOSOLIDS

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The purpose of this study was to determine the prevalence of antibiotic resistant bacteria and endotoxin in soil following land application of biosolids. Soil was collected over a 15 month period following land application of biosolids, and antibiotic resistance was ascertained using clinically rel...

  2. Quantitative Limulus lysate assay for endotoxin and the effect of plasma.

    PubMed Central

    Hurley, J C; Tosolini, F A; Louis, W J

    1991-01-01

    The effects of plasma and chromogenic substrate on the kinetics of the endotoxin-activated Limulus amoebocyte lysate (LAL) assay were determined. A linear correlation was observed between the rate of development of turbidity (optical density 405) with the LAL reagent and the concentration of endotoxin over a four log ten-fold range. Like chromogenic substrate, the addition of dilution and heat treated plasma to the reaction resulted in an increase in optical density proportional to the concentration of plasma present. The presence of the treated plasma also resulted in an accelerated increase in optical density with comparable results when testing plasma at different concentrations and, additionally, serum. This accelerated increase in optical density may not be recognised in assays that monitor the progress of the reaction at a single time point and may confound assays of plasma samples that use chromogenic substrate. Plasma obtained from endotoxin sensitive and resistant strains of mice showed similar effects. The use of kinetic methodology means that a quantitative assay for endotoxin in plasma can be achieved, its variability comparable with that seen with semiquantitative serial dilution but with greater economy of the LAL reagent. PMID:1960219

  3. A comparison of equine and bovine sera as sources of lipopolysaccharide-binding protein activity in equine monocytes incubated with lipopolysaccharide.

    PubMed

    Figueiredo, Monica D; Salter, Caroline E; Hurley, David J; Moore, James N

    2008-02-15

    Lipopolysaccharide-binding protein (LBP) is an acute phase protein that binds the lipid A moiety of lipopolysaccharide (LPS) and transfers LPS monomers to soluble CD14 in plasma or membrane bound CD14 on mononuclear phagocytes. The result of these interactions is activation of the TLR4 receptor complex, and the synthesis and release of inflammatory mediators. Inclusion of LBP in cellular assays increases the sensitivity of cells expressing CD14 to LPS. Therefore, the objectives of this study were to (1) compare differentially treated sera from cattle and horses as sources of LBP activity using LPS-induced expression of procoagulant activity (PCA) by equine monocytes as a readout and (2) evaluate the use of commercial equine serum as a source of LBP activity using LPS concentration response and time course studies to validate the response. Monocytes were isolated from eight horses and incubated with five different serum preparations in the presence or absence of Escherichia coli LPS. The sera tested were heat-inactivated fetal bovine serum (HI-FBS), pooled commercial equine serum (CES), heat-inactivated pooled commercial equine serum (HI-CES), autologous equine serum (AES), and heat-inactivated autologous equine serum (HI-AES). In the absence of LPS, monocytes from half of the horses in the study had increased expression of PCA when incubated with HI-FBS alone; PCA was unaffected by incubation with the other sera. There was a four-fold increase in PCA when monocytes were incubated with LPS in the presence of CES, HI-CES or AES compared to LPS without serum. The combination of HI-FBS and LPS increased PCA 20-fold compared to LPS without serum. The HI-AES serum lacked significant LBP activity. Whereas maximal expression of PCA was induced by 1ng/ml of LPS in the absence of serum, inclusion of 1% CES reduced the LPS concentration required for maximal PCA to 30pg/ml. Monocytes incubated with LPS in the presence of CES had increased PCA at 3h and peaked at 6h. In conclusion, monocytes from many horses are directly stimulated by HI-FBS, suggesting that HI-FBS is not an optimal source of LBP for in vitro studies of LPS with equine monocytes. In contrast, CES and AES are effective sources of LBP activity for such studies, as they do not directly induce activation. Although the heat inactivation process did not affect the LBP activity in CES, it ablated LBP activity in AES. Consequently, investigators are advised to utilize either CES or AES in future studies, but not heat-inactivated AES. PMID:18023485

  4. IL-15 cis presentation is required for optimal NK cell activation in lipopolysaccharide-mediated inflammatory conditions.

    PubMed

    Zanoni, Ivan; Spreafico, Roberto; Bodio, Caterina; Di Gioia, Marco; Cigni, Clara; Broggi, Achille; Gorletta, Tatiana; Caccia, Michele; Chirico, Giuseppe; Sironi, Laura; Collini, Maddalena; Colombo, Mario P; Garbi, Natalio; Granucci, Francesca

    2013-09-26

    Natural killer (NK) cells have antitumor, antiviral, and antibacterial functions, and efforts are being made to manipulate them in immunotherapeutic approaches. However, their activation mechanisms remain poorly defined, particularly during bacterial infections. Here, we show that upon lipopolysaccharide or E. coli exposure, dendritic cells (DCs) produce three cytokines-interleukin 2 (IL-2), IL-18, and interferon ? (IFN-?)-necessary and sufficient for NK cell activation. IFN-? enhances NK cell activation by inducing IL-15 and IL-15 receptor ? not only in DCs but, surprisingly, also in NK cells. This process allows the transfer of IL-15 on NK cell surface and its cis presentation. cis-presented NK cell-derived and trans-presented DC-derived IL-15 contribute equally to optimal NK cell activation. PMID:24055061

  5. [Comparative characterization of the physico-chemical properties of lipopolysaccharides of Yersinia pestis and R-mutants of enterobacteria].

    PubMed

    Gremiakova, T A; Fomchenkov, V M; Fursova, N K; Volkovo?, K I

    1996-01-01

    Electrokinetic potentials (EKP) of the cells of R mutants of Escherichia coli and Salmonella minnesota and cells of Yersinia pestis strains EV (line NIIEG), 358/12 P-, TWJ, Java, and 231 (708) were determined, as well as EKP of lipopolysaccharide (LPS) preparations isolated from these bacteria. The electric characteristics of the cell surfaces of the strains under investigation were demonstrated to correlate with the LPS charge and the reduction extent of their molecules. Acidic hydrolysis of LPS on the cell surface resulted in the leveling of the distinctions in EKP values (their reduction to the same level). EKP values and the size of LPS micelles of the studied Y. pestis strains corresponded to those of the deep R mutants of enterobacteria, while the aggregation extent of the molecules was higher for Y. pestis. PMID:9102553

  6. Apoptotic Cells Protect Mice against Lipopolysaccharide-Induced Shock1

    E-print Network

    Fan, Jianqing

    have therapeutic potential for the treatment of septic shock. The Journal of Immunology, 2008, 180Apoptotic Cells Protect Mice against Lipopolysaccharide-Induced Shock1 Yi Ren,2 *§ Yi Xie,* Guoping agent of septic shock. There is a lack of effective therapies. In vitro studies have shown that uptake

  7. ORIGINAL RESEARCH Attenuation of Lipopolysaccharide-Induced Lung Vascular

    E-print Network

    Gardel, Margaret

    ORIGINAL RESEARCH Attenuation of Lipopolysaccharide-Induced Lung Vascular Stiffening by Lipoxin Reduces Lung Inflammation Fanyong Meng1 , Isa Mambetsariev1 , Yufeng Tian1 , Yvonne Beckham2 , Angelo. Birukova1 1 Lung Injury Center, Section of Pulmonary and Critical Care Medicine, Department of Medicine

  8. Characterization of the Lipopolysaccharides and Capsules of Shewanella spp.

    SciTech Connect

    Korenevsky, Anton A.; Vinogradov, Evgeny; Gorby, Yuri A.; Beveridge, Terrance J.

    2002-09-04

    Electron microscopy, sodium dodecyl sulfate-polyarcylamide gel electrophoresis with silver staining and 1H, 13C, and 31P-nuclear magnetic resonance (NMR) were used to detect and characterize the lipopolysaccharides produced smooth LPS (and/or capsular polysaccharides). These same polymers in S. algae may also contribute to this opportunistic pathogen's ability to promote infection.

  9. Regular paper Molecular characterization of the lipopolysaccharide/platelet activating

    E-print Network

    Dennis, Edward A.

    Regular paper Molecular characterization of the lipopolysaccharide/platelet activating factor) upon stimulation with platelet-activating factor (PAF) and zymosan. The response to PAF is dependent pathway is triggered by platelet-activating factor (PAF). PAF itself does not promote a significant

  10. O-antigen and Core Carbohydrate of Vibrio fischeri Lipopolysaccharide

    E-print Network

    McFall-Ngai, Margaret

    O-antigen and Core Carbohydrate of Vibrio fischeri Lipopolysaccharide COMPOSITION AND ANALYSIS, University of Iowa, Iowa City, Iowa 52242 Background: The structure and function of the Vibrio fischeri O of bacterial colonization of the squid light organ. Vibrio fischeri exists in a symbiotic relationship

  11. Endotoxin-induced nitric oxide production rescues airway growth and maturation in atrophic fetal rat lung explants

    SciTech Connect

    Rae, C.; Cherry, J.I.; Land, F.M.; Land, S.C. . E-mail: s.c.land@dundee.ac.uk

    2006-10-13

    Inflammation induces premature maturation of the fetal lung but the signals causing this effect remain unclear. We determined if nitric oxide (NO) synthesis, evoked by Escherichia coli lipopolysaccharide (LPS, 2 {mu}g ml{sup -1}), participated in this process. Fetal rat lung airway surface complexity rose 2.5-fold over 96 h in response to LPS and was associated with increased iNOS protein expression and activity. iNOS inhibition by N6-(1-iminoethyl)-L-lysine-2HCl (L-NIL) abolished this and induced airway atrophy similar to untreated explants. Surfactant protein-C (SP-C) expression was also induced by LPS and abolished by L-NIL. As TGF{beta} suppresses iNOS activity, we determined if feedback regulation modulated NO-dependent maturation. LPS induced TGF{beta}1 release and SMAD4 nuclear translocation 96 h after treatment. Treatment of explants with a blocking antibody against TGF{beta}1 sustained NO production and airway morphogenesis whereas recombinant TGF{beta}1 antagonized these effects. Feedback regulation of NO synthesis by TGF{beta} may, thus, modulate airway branching and maturation of the fetal lung.

  12. Effect of Bacterial Lipopolysaccharide Contamination on Gutta Percha- versus Resilon-Induced Human Monocyte Cell Line Toxicity

    PubMed Central

    Hadjati, Jamshid; Assadian, Hadi; Ghorbanzadeh, Abdollah; Nourizadeh, Maryam; Fattah, Tahereh; Shokouhinejad, Noushin

    2015-01-01

    Objectives: Cytotoxic effects of obturation materials were tested in presence and absence of endotoxin on human monocytes in vitro. Materials and Methods: Human monocytes from THP-1 cell line were cultured. Three millimeters from the tip of each Resilon and gutta percha points were cut and directly placed at the bottom of the culture wells. Cultured cells were exposed to gutta percha (groups G1 and G2) and Resilon (R1 and R2). Ten ?g/ml bacterial lipopolysaccharide (LPS) was added to the culture wells in groups G1 and R1. Positive control included the bacterial LPS without the root canal filling material and the negative control contained the cells in culture medium only. Viability of cells was tested in all groups after 24, 48, and 72 hours using the methylthiazolyldiphenyl-tetrazolium bromide (MTT) assay for at least 3 times to obtain reproducible results. Optical density values were read and the data were analyzed using three-way ANOVA and post hoc statistical test. Results: The results showed that cells in G2 had the lowest rate of viability at 24 hours, but the lowest rate of viable cells was recorded in G1 at 48 and 72 hours. The effect of LPS treatment was not statistically significant. Resilon groups showed cell viability values higher than those of gutta percha groups, although statistically non-significant (P=0.105). Cell viability values were lower in gutta percha than Resilon groups when LPS-treated and LPS-untreated groups were compared independently at each time point. Conclusion: It could be concluded that none of the tested root canal filling materials had toxic effects on cultured human monocyte cells whether in presence or absence of LPS contamination. PMID:26056523

  13. Treadmill and wheel exercise alleviate lipopolysaccharide-induced short-term memory impairment by enhancing neuronal maturation in rats.

    PubMed

    Kim, Sung-Eun; Ko, Il-Gyu; Park, Chang-Youl; Shin, Mal-Soon; Kim, Chang-Ju; Jee, Yong-Seok

    2013-01-01

    Lipopolysaccharide (LPS) is an endotoxin derived from Gram?negative bacteria, which induces brain inflammation. LPS?induced brain inflammation deteriorates hippocampus?dependent cognitive deficits. In the present study, we investigated the effects of forced treadmill exercise and voluntary wheel exercise on short?term memory in relation to neuronal maturation in LPS?induced brain inflammation of rats. Brain inflammation in rats was induced by an injection of LPS into the cerebral ventricle. Short?term memory was evaluated using a step?down avoidance task. Cell proliferation in the hippocampal dentate gyrus was determined by 5?bromo?2'?deoxyuridine (BrdU), a marker of new cells, immunohistochemistry. Western blot analysis for the determination of doublecortin (DCX), a marker of immature neurons and neuronal nuclear antigen (NeuN), a marker of mature neurons, was performed. In the present study, LPS?induced brain inflammation impaired short?term memory by increasing DCX expression and suppressing NeuN expression. These results suggest that LPS?induced brain inflammation disturbs neuronal maturation. The number of BrdU?positive cells in the hippocampal dentate gyrus was increased by LPS injection. This increase in the number of BrdU?positive cells can be ascribed to the increase in the number of of immature neurons following LPS injection. On the other hand, forced treadmill exercise and voluntary wheel exercise improved brain inflammation?induced short?term memory impairment by suppressing DCX expression and increasing NeuN expression, enhancing neuronal maturation. Forced treadmill exercise and voluntary wheel exercise showed similar efficacy. From these results, it can be inferred that forced treadmill exercise and voluntary wheel exercise may improve memory function deteriorated by brain inflammation. PMID:23128607

  14. Serum Levels of Lipopolysaccharide and 1,3-?-D-Glucan Refer to the Severity in Patients with Crohn's Disease

    PubMed Central

    Guo, Yanmin; Zhou, Guangxi; Yang, Wenjing; He, Zhenkun; Liu, Zhanju

    2015-01-01

    Objectives. Interactions between the host and gut microbial community contribute to the pathogenesis of Crohn's disease (CD). In this study, we aimed to detect lipopolysaccharide (LPS) and 1,3-?-D-glucan (BG) in the sera of CD patients and clarify the potential role in the diagnosis and therapeutic approaches. Materials and Methods. Serum samples were collected from 46 patients with active CD (A-CD), 22 CD patients at remission stage (R-CD), and 20 healthy controls, and the levels of LPS, BG, and TNF in sera were determined by ELISA. Moreover, sixteen patients with A-CD received anti-TNF monoclonal antibody therapy (infliximab, IFX) at a dose of 5?mg/kg body weight at weeks 0, 2, and 6, and the levels of LPS and BG were also tested at week 12 after the first intravenous infusion. Results. Serum levels of LPS and BG were found to be markedly increased in A-CD patients compared with R-CD patients and healthy controls (P < 0.05). They were also observed to be positively correlated with CDAI, ESR, and SES-CD, respectively (P < 0.05). Furthermore, the levels of TNF in sera had a significant correlation with LPS and BG, respectively. The concentrations of LPS and BG were demonstrated to be significantly downregulated in the sera of A-CD patients 12 weeks after IFX treatment (P < 0.05), suggesting that blockade of TNF could inhibit bacterial endotoxin absorption, partially through improving intestinal mucosal barrier. Conclusions. Serum levels of LPS and BG are significantly increased in A-CD patients and positively correlated with the severity of the disease. Blockade of intestinal mucosal inflammation with IFX could reduce the levels of LPS and BG in sera. Therefore, this study has shed some light on measurement of serum LPS and BG in the diagnosis and treatment of CD patients. PMID:26106258

  15. Bacterial lipopolysaccharide induces rainbow trout myotube atrophy via Akt/FoxO1/Atrogin-1 signaling pathway.

    PubMed

    Aedo, J E; Reyes, A E; Avendaño-Herrera, R; Molina, A; Valdés, J A

    2015-11-01

    Lipopolysaccharide (LPS) is considered as a powerful inducer of muscle atrophy in higher vertebrates due to skeletal muscle cell recognition of the endotoxin and a consequent activation of catabolic signaling pathways. In contrast, there is no evidence of LPS directly inducing skeletal muscle atrophy in lower vertebrates, such as fish. For years it has been assumed that fish are resistant to LPS, mainly due to differences in the key features of toll-like receptor (TLR) signaling pathways when compared with mammals. In this study, we report that the stimulation of cultured rainbow trout (Oncorhynchus mykiss) myotubes with LPS (100 ng/ml) resulted in a transient decrease in the pAkt/Akt ratio, a subsequent reduction in the pFoxO1/FoxO1 ratio, and a significant increase in atrogin-1 transcript expression. Preincubation with polymyxin B, an LPS-neutralizing agent, and 740 Y-P, an agonist of p85-PI3K, blocked the effects of LPS. Additionally, LPS treatment induced an increase in protein ubiquitination and a reduction in myotube diameter, both of which are associated with muscular atrophy that is not observed under polymyxin B and 740 Y-P pretreatments. Finally, rainbow trout myotubes expressed the genes tlr1, tlr3, tlr5m, tlr8a1, tlr8a2, tlr9, and tlr22, with significantly increased expressions of tlr5m and tlr9 under LPS stimulation. These results indicate that LPS is an inducer of fish skeletal muscle atrophy and suggest that TLR5M and TLR9 may play important roles in detecting LPS, which supports for the first time the hypothesis that LPS is a direct inducer of skeletal muscle atrophy in teleost species. PMID:26341977

  16. Lipopolysaccharide Renders Transgenic Mice Expressing Human Serum Amyloid P Component Sensitive to Shiga Toxin 2

    PubMed Central

    Griener, Thomas P.; Strecker, Jonathan G.; Humphries, Romney M.; Mulvey, George L.; Fuentealba, Carmen; Hancock, Robert E. W.; Armstrong, Glen D.

    2011-01-01

    Transgenic C57BL/6 mice expressing human serum amyloid P component (HuSAP) are resistant to Shiga toxin 2 (Stx2) at dosages that are lethal in HuSAP-negative wild-type mice. However, it is well established that Stx2 initiates extra-intestinal complications such as the haemolytic-uremic syndrome despite the presence of HuSAP in human sera. We now demonstrate that co-administering purified Escherichia coli O55 lipopolysaccharide (LPS), at a dosage of 300 ng/g body weight, to HuSAP-transgenic mice increases their susceptibility to the lethal effects of Stx2. The enhanced susceptibility to Stx2 correlated with an increased expression of genes encoding the pro-inflammatory cytokine TNF? and chemokines of the CXC and CC families in the kidneys of LPS-treated mice, 48 hours after the Stx2/LPS challenge. Co-administering the glucocorticoid dexamethasone, but not the LPS neutralizing cationic peptide LL-37, protected LPS-sensitized HuSAP-transgenic mice from lethal doses of Stx2. Dexamethasone protection was specifically associated with decreased expression of the same inflammatory mediators (CXC and CC-type chemokines and TNF?) linked to enhanced susceptibility caused by LPS. The studies reveal further details about the complex cascade of host-related events that are initiated by Stx2 as well as establish a new animal model system in which to investigate strategies for diminishing serious Stx2-mediated complications in humans infected with enterohemorrhagic E. coli strains. PMID:21731756

  17. Structural and functional studies of conserved nucleotide-binding protein LptB in lipopolysaccharide transport

    SciTech Connect

    Wang, Zhongshan; Xiang, Quanju; Zhu, Xiaofeng; Dong, Haohao; He, Chuan; Wang, Haiyan; Zhang, Yizheng; Wang, Wenjian; Dong, Changjiang

    2014-09-26

    Highlights: • Determination of the structure of the wild-type LptB in complex with ATP and Mg{sup 2+}. • Demonstrated that ATP binding residues are essential for LptB’s ATPase activity and LPS transport. • Dimerization is required for the LptB’s function and LPS transport. • Revealed relationship between activity of the LptB and the vitality of E. coli cells. - Abstract: Lipopolysaccharide (LPS) is the main component of the outer membrane of Gram-negative bacteria, which plays an essential role in protecting the bacteria from harsh conditions and antibiotics. LPS molecules are transported from the inner membrane to the outer membrane by seven LPS transport proteins. LptB is vital in hydrolyzing ATP to provide energy for LPS transport, however this mechanism is not very clear. Here we report wild-type LptB crystal structure in complex with ATP and Mg{sup 2+}, which reveals that its structure is conserved with other nucleotide-binding proteins (NBD). Structural, functional and electron microscopic studies demonstrated that the ATP binding residues, including K42 and T43, are crucial for LptB’s ATPase activity, LPS transport and the vitality of Escherichia coli cells with the exceptions of H195A and Q85A; the H195A mutation does not lower its ATPase activity but impairs LPS transport, and Q85A does not alter ATPase activity but causes cell death. Our data also suggest that two protomers of LptB have to work together for ATP hydrolysis and LPS transport. These results have significant impacts in understanding the LPS transport mechanism and developing new antibiotics.

  18. Gender differences in the effect of occupational endotoxin exposure on impaired lung function and death: the Shanghai Textile Worker Study

    PubMed Central

    Zhang, Feng-ying; Lin, Xinyi; Zheng, Bu-yong; Dai, Hei-Lian; Su, Li; Cai, Tianxi; Christiani, David C.

    2014-01-01

    OBJECTIVE Airborne endotoxin exposure has both adverse and protective health effects. Studies show males have augmented acute inflammatory responses to endotoxin. In this longitudinal cohort study we investigated the effect of long-term exposure to endotoxin in cotton dust on health, and determined whether these effects differ by gender. METHODS In the Shanghai Textile Worker Study, 447 cotton and 472 control silk textile workers were followed from 1981 to 2011 with repeated measures of occupational endotoxin exposure, spirometry, and health questionnaires. Impaired lung function was defined as a decline in forced expiratory volume in one second to less than the 5th percentile of population predicted. Death was ascertained by death registries. We used Cox proportional hazards models to assess the effect of endotoxin exposure on the time to development of impaired lung function and death. RESULTS 128 deaths and 164 diagnoses of impaired lung function were ascertained between 1981 and 2011. Hazard ratios (HRs) for the composite endpoint of impaired lung function or death was 1.47 (95% CI 1.09-1.97) for cotton vs. silk workers and 1.04 (95% CI 1.01-1.07) per 10,000 endotoxin units (EU)/m3-years increase in exposure. HRs for all-cause mortality was 1.36 (95% CI 0.93-1.99) for cotton vs. silk workers and 1.04 (95% CI 0.99-1.08) per 10,000 EU/m3-years. The risk associated with occupational endotoxin exposure was elevated only in men. CONCLUSIONS Occupational endotoxin exposure is associated with an increase in the risk of impaired lung function and all-cause mortality in men. PMID:24297825

  19. Evaluation of the endotoxin binding efficiency of clay minerals using the Limulus Amebocyte lysate test: an in vitro study

    PubMed Central

    2014-01-01

    Endotoxins are part of the cell wall of Gram-negative bacteria. They are potent immune stimulators and can lead to death if present in high concentrations. Feed additives, which bind endotoxins in the gastrointestinal tract of animals, could help to prevent their negative impact. The objective of our study was to determine the potential of a bentonite (Bentonite 1), a sodium bentonite (Bentonite 2), a chemically treated smectite (Organoclay 1) and a modified attapulgite (Organoclay 2) to bind endotoxins in vitro. Polymyxin B served as positive control. The kinetic chromogenic Limulus Amebocyte lysate test was adapted to measure endotoxin activity. Firstly, a single sorption experiment (10 endotoxin units/mL (EU/mL)) was performed. Polymyxin B and organoclays showed 100% binding efficiency. Secondly, the adsorption efficiency of sorbents in aqueous solution with increasing endotoxin concentrations (2,450 – 51,700 EU/mL) was investigated. Organoclay 1 (0.1%) showed a good binding efficiency in aqueous solution (average 81%), whereas Bentonite 1 (0.1%) obtained a lower binding efficiency (21-54%). The following absorbent capacities were calculated in highest endotoxin concentration: 5.59 mg/g (Organoclay 1)?>?3.97 mg/g (Polymyxin B)?>?2.58mg/g (Organoclay 2)?>?1.55 mg/g (Bentonite 1)?>?1.23 mg/g (Bentonite 2). Thirdly, a sorption experiment in artificial intestinal fluid was conducted. Especially for organoclays, which are known to be unspecific adsorbents, the endotoxin binding capacity was significantly reduced. In contrast, Bentonite 1 showed comparable results in artificial intestinal fluid and aqueous solution. Based on the results of this in vitro study, the effect of promising clay minerals will be investigated in in vivo trials. PMID:24383578

  20. Determination of single nucleotide variants in Escherichia coli DH5? by using short-read sequencing.

    PubMed

    Song, Yoseb; Lee, Bo-Rahm; Cho, Suhyung; Cho, Yoo-Bok; Kim, Seon-Won; Kang, Taek Jin; Kim, Sun Chang; Cho, Byung-Kwan

    2015-06-01

    Escherichia coli DH5? is a common laboratory strain that provides an important platform for routine use in cloning and synthetic biology applications. Many synthetic circuits have been constructed and successfully expressed in E. coli DH5?; however, its genome sequence has not been determined yet. Here, we determined E. coli DH5? genome sequence and identified genetic mutations that affect its phenotypic functions by using short-read sequencing. The sequencing results clearly described the genotypes of E. coli DH5?, which aid in further studies using the strain. Additionally, we observed 105 single nucleotide variants (SNVs), 83% of which were detected in protein-coding regions compared to the parental strain E. coli DH1. Interestingly, 23% of the protein-coding regions have mutations in their amino acid residues, whose biological functions were categorized into two-component systems, peptidoglycan biosynthesis and lipopolysaccharide biosynthesis. These results underscore the advantages of E. coli DH5?, which tolerates the components of transformation buffer and expresses foreign plasmids efficiently. Moreover, these SNVs were also observed in the commercially available strain. These data provide the genetic information of E. coli DH5? for its future application in metabolic engineering and synthetic biology. PMID:25934703

  1. Genipin attenuates lipopolysaccharide-induced persistent changes of emotional behaviors and neural activation in the hypothalamic paraventricular nucleus and the central amygdala nucleus.

    PubMed

    Araki, Ryota; Hiraki, Yosuke; Yabe, Takeshi

    2014-10-15

    Sickness behavior is a series of behavioral and psychological changes that develop in inflammatory disease, including infections and cancers. Administration of the bacterial endotoxin lipopolysaccharide (LPS) induces sickness behavior in rodents. Genipin, an aglycon derived from an iridoid glycoside geniposide extracted from the fruit of Gardenia jasminoides, has anti-inflammatory and antidepressant activities. However, the effects of genipin on inflammation-induced changes in emotional behaviors are unknown. In this study, we examined the effects of genipin on LPS-induced inflammation in BV-2 cells and sickness behavior in mice. Pretreatment with genipin inhibited LPS-induced increases in NO production and reduced the mRNA levels of inflammation-related genes (iNOS, COX-2, IL-1? and IL-6) in BV-2 cells. Oral administration of genipin ameliorated LPS-induced depressive-like behavior in the forced swim test and social behavior deficits 24h after LPS administration in mice. LPS-induced expression of mRNAs for inflammation-related genes and the number of c-fos immunopositive cells decreased in the paraventricular nucleus (PVN) of the hypothalamus and the central nucleus of the amygdala (CeA), suggesting that genipin attenuates LPS-induced changes of emotional behaviors through inhibition of neural activation and inflammatory responses in the PVN and CeA. These novel pharmacological effects of genipin may be useful for treatment of patients with sickness behavior. PMID:25084220

  2. In-Field Implementation of a Recombinant Factor C Assay for the Detection of Lipopolysaccharide as a Biomarker of Extant Life within Glacial Environments.

    PubMed

    Barnett, Megan J; Wadham, Jemma L; Jackson, Miriam; Cullen, David C

    2012-01-01

    The discovery over the past two decades of viable microbial communities within glaciers has promoted interest in the role of glaciers and ice sheets (the cryosphere) as contributors to subglacial erosion, global biodiversity, and in regulating global biogeochemical cycles. In situ or in-field detection and characterisation of microbial communities is becoming recognised as an important approach to improve our understanding of such communities. Within this context we demonstrate, for the first time, the ability to detect Gram-negative bacteria in glacial field-environments (including subglacial environments) via the detection of lipopolysaccharide (LPS); an important component of Gram-negative bacterial cell walls. In-field measurements were performed using the recently commercialised PyroGene® recombinant Factor C (rFC) endotoxin detection system and used in conjunction with a handheld fluorometer to measure the fluorescent endpoint of the assay. Twenty-seven glacial samples were collected from the surface, bed and terminus of a low-biomass Arctic valley glacier (Engabreen, Northern Norway), and were analysed in a field laboratory using the rFC assay. Sixteen of these samples returned positive LPS detection. This work demonstrates that LPS detection via rFC assay is a viable in-field method and is expected to be a useful proxy for microbial cell concentrations in low biomass environments. PMID:25585634

  3. In-Field Implementation of a Recombinant Factor C Assay for the Detection of Lipopolysaccharide as a Biomarker of Extant Life within Glacial Environments

    PubMed Central

    Barnett, Megan J.; Wadham, Jemma L.; Jackson, Miriam; Cullen, David C.

    2012-01-01

    The discovery over the past two decades of viable microbial communities within glaciers has promoted interest in the role of glaciers and ice sheets (the cryosphere) as contributors to subglacial erosion, global biodiversity, and in regulating global biogeochemical cycles. In situ or in-field detection and characterisation of microbial communities is becoming recognised as an important approach to improve our understanding of such communities. Within this context we demonstrate, for the first time, the ability to detect Gram-negative bacteria in glacial field-environments (including subglacial environments) via the detection of lipopolysaccharide (LPS); an important component of Gram-negative bacterial cell walls. In-field measurements were performed using the recently commercialised PyroGene® recombinant Factor C (rFC) endotoxin detection system and used in conjunction with a handheld fluorometer to measure the fluorescent endpoint of the assay. Twenty-seven glacial samples were collected from the surface, bed and terminus of a low-biomass Arctic valley glacier (Engabreen, Northern Norway), and were analysed in a field laboratory using the rFC assay. Sixteen of these samples returned positive LPS detection. This work demonstrates that LPS detection via rFC assay is a viable in-field method and is expected to be a useful proxy for microbial cell concentrations in low biomass environments. PMID:25585634

  4. Inflammatory Cytokines and Cell Death in BEAS-2B Lung Cells Treated with Soil Dust, Lipopolysaccharide, and Surface-Modified Particles

    PubMed Central

    Veranth, John M.; Reilly, Christopher A.; Veranth, Martha M.; Moss, Tyler A.; Langelier, Charles R.; Lanza, Diane L.; Yost, Garold S.

    2008-01-01

    Cultured human lung epithelial cells (BEAS-2B) were treated in vitro with PM2.5-enriched particles of soil-derived mineral dust from nine sites in the western United States. The particle samples simulate windblown dust and vehicle-generated emissions from unpaved roads. Five of the sites yielded relatively benign dust. Particles from three sites caused IL-6 release when cells were treated for 24 h at doses from 20 to 80 ?g/cm2, and particles from one site were highly cytotoxic. The particle components or characteristics that caused the IL-6 release were stable at temperatures below 150°C, but were inactivated by treatment at 300–550°C. The active factors were also associated predominantly with the insoluble fraction, and were partially attenuated by leaching with aqueous and organic solvents. The IL-6 release caused by the particles was much greater than the cytokine response to either lipopolysaccharide (LPS) or to surrogate particles of titanium dioxide mixed with LPS, suggesting that endotoxin was not a major factor in the inflammatory response. The release of IL-8 in response to particle treatment was qualitatively similar to the IL-6 response, but release of TNF-? was not detected at the 24-h time point. The combined results support the hypothesis that some ambient dusts from geological sources can cause cell death and cytokine release in a lung cell line that is widely used as an in vitro model to study mechanisms of environmental respiratory injury. PMID:15310859

  5. Polyphenolic extracts from cowpea (Vigna unguiculata) protect colonic myofibroblasts (CCD18Co cells) from lipopolysaccharide (LPS)-induced inflammation--modulation of microRNA 126.

    PubMed

    Ojwang, Leonnard O; Banerjee, Nivedita; Noratto, Giuliana D; Angel-Morales, Gabriela; Hachibamba, Twambo; Awika, Joseph M; Mertens-Talcott, Susanne U

    2015-01-01

    Cowpea (Vigna unguiculata) is a drought tolerant crop with several agronomic advantages over other legumes. This study evaluated varieties from four major cowpea phenotypes (black, red, light brown and white) containing different phenolic profiles for their anti-inflammatory property on non-malignant colonic myofibroblasts (CCD18Co) cells challenged with an endotoxin (lipopolysaccharide, LPS). Intracellular reactive oxygen species (ROS) assay on the LPS-stimulated cells revealed antioxidative potential of black and red cowpea varieties. Real-time qRT-PCR analysis in LPS-stimulated cells revealed down-regulation of proinflammatory cytokines (IL-8, TNF-?, VCAM-1), transcription factor NF-?B and modulation of microRNA-126 (specific post-transcriptional regulator of VCAM-1) by cowpea polyphenolics. The ability of cowpea polyphenols to modulate miR-126 signaling and its target gene VCAM-1 were studied in LPS-stimulated endothelial cells transfected with a specific inhibitor of miR-126, and treated with 10 mg GAE/L black cowpea extract where the extract in part reversed the effect of the miR-126 inhibitor. This suggests that cowpea may exert their anti-inflammatory activities at least in part through induction of miR-126 that then down-regulate VCAM-1 mRNA and protein expressions. Overall, Cowpea therefore is promising as an anti-inflammatory dietary component. PMID:25300227

  6. Trehalose alleviates PC12 neuronal death mediated by lipopolysaccharide-stimulated BV-2 cells via inhibiting nuclear transcription factor NF-?B and AP-1 activation.

    PubMed

    He, Qing; Wang, Ying; Lin, Wei; Zhang, Qiong; Zhao, Jue; Liu, Feng-Tao; Tang, Yi-Lin; Xiao, Bao-Guo; Wang, Jian

    2014-11-01

    Inflammation is implicated in the pathogenesis of Parkinson's disease (PD). Trehalose is a disaccharide which exhibits a variety of effects like anti-aggregation, autophagy enhancement in PD. It has also been known to suppress inflammation in many experimental models, involving endotoxin shock, murine dry eye and subarachnoid hemorrhage. However, whether trehalose has an anti-inflammation effect on PD is largely unknown. In the present study, we found trehalose inhibited generation of interleukin-1?, interleukin-6, tumor necrosis factor-?, and nitric oxide in the conditioned medium released from lipopolysaccharide (LPS)-stimulated BV-2 cells. LPS-induced nuclear transcription factors of NF-?B and AP-1 activation were also inhibited by trehalose. Then the conditioned medium of BV-2 cells was applied to PC12 neurons. As a result, both MTT and LDH indicated that trehalose decreased PC12 neuronal death. TUNEL assay showed that trehalose suppressed apoptosis of PC12 neurons. These results implied that trehalose exerted a protective effect on PC12 neurons against the neurotoxic effect triggered by BV-2 microglial activation through inhibiting NF-?B and AP-1 activation and inflammatory mediators and cytokines production in BV-2 cells. PMID:25125332

  7. Antimicrobial Peptides: Insights into Membrane Permeabilization, Lipopolysaccharide Fragmentation and Application in Plant Disease Control

    PubMed Central

    Datta, Aritreyee; Ghosh, Anirban; Airoldi, Cristina; Sperandeo, Paola; Mroue, Kamal H.; Jiménez-Barbero, Jesús; Kundu, Pallob; Ramamoorthy, Ayyalusamy; Bhunia, Anirban

    2015-01-01

    The recent increase in multidrug resistance against bacterial infections has become a major concern to human health and global food security. Synthetic antimicrobial peptides (AMPs) have recently received substantial attention as potential alternatives to conventional antibiotics because of their potent broad-spectrum antimicrobial activity. These peptides have also been implicated in plant disease control for replacing conventional treatment methods that are polluting and hazardous to the environment and to human health. Here, we report de novo design and antimicrobial studies of VG16, a 16-residue active fragment of Dengue virus fusion peptide. Our results reveal that VG16KRKP, a non-toxic and non-hemolytic analogue of VG16, shows significant antimicrobial activity against Gram-negative E. coli and plant pathogens X. oryzae and X. campestris, as well as against human fungal pathogens C. albicans and C. grubii. VG16KRKP is also capable of inhibiting bacterial disease progression in plants. The solution-NMR structure of VG16KRKP in lipopolysaccharide features a folded conformation with a centrally located turn-type structure stabilized by aromatic-aromatic packing interactions with extended N- and C-termini. The de novo design of VG16KRKP provides valuable insights into the development of more potent antibacterial and antiendotoxic peptides for the treatment of human and plant infections. PMID:26144972

  8. Role of a lipopolysaccharide gene for immunogenicity of the enterobacterial common antigen.

    PubMed Central

    Schmidt, G; Mannel, D; Mayer, H; Whang, H Y; Neter, E

    1976-01-01

    It is known that only certain strains of the family of Enterobacteriaceae, notably rough (R) mutants with the type R1 or R4 core, evoked antibodies in high titers against the common enterobacterial antigen (CA) after immunization of rabbits with heated cell suspensions. The present investigation deals with genetic and immunochemical aspects of certain R1 and R4 mutants isolated from Escherichia coli 08 and various Shigella serotypes which, unexpectedly, do not induce CA antibody formation. Immunochemical and genetical (transduction and conjugation) experiments revealed that the rough phenotype of these special mutants was evoked by a mutation of pyrE-linked rfa gene, called rfaL, which is involved in translocation of O-specific polysaccharides onto the lipopolysaccharide core. The transduction of the defective rfaL, allele into appropriate rough recipients results in transductants which have simultaneously lost the ability to evoke CA antibodies. This finding suggests that a close connection exists between the function of the rfaL gene and the expression of CA immunogenicity in R1 and R4 mutants. One of the strains synthesized neither O-hapten nor CA, suggesting a mutation in a region equivalent to the rfe genes of Salmonella. PMID:57114

  9. Effects of age on the synergistic interactions between lipopolysaccharide and mechanical ventilation in mice.

    PubMed

    Smith, Lincoln S; Gharib, Sina A; Frevert, Charles W; Martin, Thomas R

    2010-10-01

    Children have a lower incidence and mortality from acute lung injury (ALI) than adults, and infections are the most common event associated with ALI. To study the effects of age on susceptibility to ALI, we investigated the responses to microbial products combined with mechanical ventilation (MV) in juvenile (21-d-old) and adult (16-wk-old) mice. Juvenile and adult C57BL/6 mice were treated with inhaled Escherichia coli 0111:B4 lipopolysaccharide (LPS) and MV using tidal volume = 15 ml/kg. Comparison groups included mice treated with LPS or MV alone and untreated age-matched control mice. In adult animals treated for 3 hours, LPS plus MV caused synergistic increases in neutrophils (P < 0.01) and IgM in bronchoalveolar lavage fluid (P = 0.03) and IL-1? in whole lung homogenates (P < 0.01) as compared with either modality alone. Although juvenile and adult mice had similar responses to LPS or MV alone, the synergistic interactions between LPS and MV did not occur in juvenile mice. Computational analysis of gene expression array data suggest that the acquisition of synergy with increasing age results, in part, from the loss of antiapoptotic responses and the acquisition of proinflammatory responses to the combination of LPS and MV. These data suggest that the synergistic inflammatory and injury responses to inhaled LPS combined with MV are acquired with age as a result of coordinated changes in gene expression of inflammatory, apoptotic, and TGF-? pathways. PMID:19901347

  10. Mechanisms involved in milk endogenous proteolysis induced by a lipopolysaccharide experimental mastitis.

    PubMed

    Moussaoui, F; Michelutti, I; Le Roux, Y; Laurent, F

    2002-10-01

    Experimental mastitis has been induced by the lipopolysaccharide (LPS) of Escherichia coli on six dairy cows in order to study the mechanisms involved in milk endogenous proteolysis during the inflammatory process. Variations in somatic cell count (SCC), plasmin activity, and total casein (CN) content were measured, and proteose-peptone content and the percentage of pH 4.6 insoluble peptides including gamma-CN have been considered as indicators of endogenous proteolysis. Furthermore, polymorphonuclear neutrophils (PMN) maturity has been evaluated by optical microscopy, and proteolysis by PMN proteinases has been studied at neutral and acidic pH in order to establish a link between caseinolysis, proteinase class, and PMN maturation. Two peaks of proteose-peptones content have been noticed for the six cows. First peak could be explained by both plasmin activity and SCC, while second peak was concomitant with a low plasmin activity but a SCC remaining high. The second peak of proteose-peptones content confirmed the role of cellular proteases in milk caseinolysis. Casein breakdown by cellular proteases was confirmed by SDS-PAGE electrophoresis, and a link between neutral proteinases activity and immature PMN recruitment was shown. Acidic proteinases activity was effective with mature PMN and during the recovery phase. PMID:12416808

  11. Depression of afferent arc of the in vivo cytotoxic T-cell immunity by bacterial lipopolysaccharides

    SciTech Connect

    Mizoguchi, K.; Nakashima, I.; Hasegawa, Y.; Isobe, K.; Kato, N.; Shimokata, K.; Kawashima, K.; Nagase, F.; Ando, K.; Yoshida, T.

    1985-10-15

    The afferent arc of the in vivo cytotoxic T-cell immunity assessed by second set rejection of ascitic allogeneic tumors was shown to be depressed by bacterial lipopolysaccharide (LPS) that was administered simultaneously with or 1 day before injection of allogeneic spleen cells as stimulators. Two different LPSs from Escherichia coli O55 and Klebsiella O3 displayed similar activities whereas dextran sulfate, concanavalin A, or poly A:U was not effective. Stimulator activities of allogeneic cells was not directly modified by LPS. Any definite suppressor activity on afferent or efferent arc of the T-cell response was not demonstrable in mice receiving LPS and allogeneic cells. Further, the LPS effect for immune depression was not diminished by whole body X-ray irradiation to the recipient at 300 R, which ablated the B-cell reactivity to LPS for polyclonal activation, or by treatment of the recipient with carrageenan, a known toxic agent to macrophages. It was suggested from these results that LPS suppresses the cytotoxic T-cell immunity by modulating responder T cells to be temporarily refractory to the allogeneic stimulus rather than by activating suppressor cells such as radiation-sensitive lymphocytes and carrageenan-sensitive macrophages.

  12. Determination of biogenic amines and endotoxin in squid, musky octopus, Norway lobster, and mussel stored at room temperature.

    PubMed

    Prester, Ljerka; Orct, Tatjana; Macan, Jelena; Vukuši?, Jelena; Kip?i?, Dubravka

    2010-12-01

    Little research has been published on the indicators of spoilage in Mediterranean molluscan shellfish and crustaceans. Thus is why we studied changes in the concentrations of endotoxin and four biogenic amines (histamine, putrescine, tyramine and cadaverine) in European common squid (Loligo subulata, Lamarck, 1798), musky octopus (Eledone moschata, Lamarck, 1798), Norway lobster (Nephrops norvegicus, Linnaeus, 1758), and mussel (Mytilus galloprovincialis, Lamarck, 1819) from the Adriatic Sea stored at room temperature for 24 h. Endotoxin load in fresh squid, Norway lobster, and mussel (<1 EU mg-1) indicated good microbiological quality of raw samples. Biogenic amine index (as the sum of histamine, putrescine, tyramine, and cadaverine) correlated well with endotoxin load in squid (r=0.978, p<0.001) and musky octopus (r=0.874, p<0.01). A good correlation was also found between endotoxin and putrescine in Norway lobster (r=0.777, p<0.05). The highest endotoxin load was found in decomposed mussels and was associated with histamine alone. In conclusion, increase in biogenic amine levels is species-specific. Endotoxin analysis could be used for rapid assessment of microbiological quality of cephalopods and shellfish. PMID:21183430

  13. Effects of total parenteral nutrition on endotoxin translocation and extent of the stress response in burned rats.

    PubMed

    Sugiura, T; Tashiro, T; Yamamori, H; Takagi, K; Hayashi, N; Itabashi, T; Toyoda, Y; Sano, W; Nitta, H; Hirano, J; Nakajima, N; Ito, I

    1999-01-01

    Postburn endotoxin translocation has been well documented. However, the relationship between the secretion of catabolic hormones, degree of endotoxin translocation, and intestinal atrophy has not been previously demonstrated. In this experiment, modulation of the secretion of catabolic hormones according to the route of nutrient administration was examined in burned animals. A total of 55 rats, with and without a burn injury, were orally or parenterally fed. Urinary excretion of epinephrine and norepinephrine (U-EN) of each rat was measured for 48 h after burn injury as an indicator of the stress response. Evaluations of intestinal atrophy and endotoxin contents in the liver and spleen were also done 48 h after burn injury. U-EN after burn injury in rats administered total parenteral nutrition (TPN) was higher than in those fed orally. Endotoxin translocation and intestinal atrophy after thermal injury were also augmented by TPN. A significant positive correlation between U-EN and endotoxin content of the liver, and a negative correlation between U-EN and weight of the intestine, were observed. TPN enhances the stress response after burn injury. An increase in endotoxin translocation and intestinal atrophy by TPN are closely related to enhancement of the stress response. PMID:10422088

  14. Assessing the removal potential of soil-aquifer treatment system (soil column) for endotoxin.

    PubMed

    Guizani, Mokhtar; Kato, Hideaki; Funamizu, Naoyuki

    2011-06-01

    Soil-aquifer treatment (SAT) of wastewater is an increasingly valued practice for replenishing aquifers due to ease of operation and low maintenance needs and therefore low cost. In this study, we investigated the fate of endotoxins through laboratory-scale SAT soil columns over a four month period. The effluent of rapid sand filtration was run through the columns under gravity flow conditions. Four SAT columns were packed with four different filter materials (fine sand, medium sand, coarse sand and very coarse sand). The effluent of rapid sand filtration (average dissolved organic carbon (DOC) = 4 mg l(-1) and average endotoxin concentration = 4 EU ml(-1)) was collected from a domestic wastewater treatment plant in Sapporo, Japan. DOC removal ranged from 12.5% to greater than 22.5% during the study, with DOC levels averaging 3.1 and 3.5 mg l(-1) for the SAT columns packed with different soils. Endotoxin transformation exhibited different profiles, depending on the time and soil type. Reduction in endotoxin concentration averaged 64.3% and was as high as 86.7% across the soil columns 1, 2, 3 and 4, respectively. While DOC removal was gradual, the reductions in endotoxin levels were rather rapid and most of the removal was achieved in the top layers. Soil with a larger grain size had lower efficiency in removing endotoxin. Tests were performed to evaluate the transformation of organic matter showing endotoxicity and to determine the mechanisms responsible for changes in the structural and size properties of dissolved organic matter (OM) during SAT. Dissolved OM was fractionated using Sep-Pack C18 Cartridges into hydrophobic and hydrophilic fractions. Dialysis tubes with different molecular weight cut-offs were used to perform size fractions of OM showing endotoxicity. Evaluation of the transformation of organic matter showing endotoxicity during SAT indicated that both hydrophobic and large molecules were reduced. Moreover, experimental findings showed that adsorption test data fit to the Freundlich isotherm and were affected by the particle grain size with higher adsorption capacity for fine and medium sand. PMID:21566853

  15. Escherichia coli biofilms

    PubMed Central

    Beloin, Christophe; Roux, Agnès; Ghigo, Jean-Marc

    2008-01-01

    Escherichia coli is a predominant species among facultative anaerobic bacteria of the gastrointestinal tract. Both its frequent community lifestyle and the availability of a wide array of genetic tools contributed to establish E. coli as a relevant model organism for the study of surface colonization. Several key factors, including different extracellular appendages, are implicated in E. coli surface colonization and their expression and activity are finely regulated, both in space and time, to ensure productive events leading to mature biofilm formation. This chapter will present known molecular mechanisms underlying biofilm development in both commensal and pathogenic E. coli. PMID:18453280

  16. [The idiosyncratic hepatotoxicity of Polygonum multiflorum based on endotoxin model].

    PubMed

    Li, Chun-yu; Li, Xiao-fei; Tu, Can; Li, Na; Ma, Zhi-jie; Pang, Jing-yao; Jia, Ge-liu-chang; Cui, He-rong; You, Yun; Song, Hai-bo; Du, Xiao-xi; Zhao, Yan-ling; Wang, Jia-bo; Xiao, Xiao-he

    2015-01-01

    The liver injury induced by Polygonum multiflorum Thunb. (PM) was investigated based on idiosyncratic hepatotoxicity model co-treated with lipopolysaccharide (LPS) at a non-hepatotoxic dose. Sprague-Dawley (SD) rats were intragastrically administered with three doses (18.9, 37.8, 75.6 g crude drug per kg body weight) of 50% alcohol extracts of PM alone or co-treated with non-toxic dose of LPS (2.8 mg·kg(-1)) via tail vein injection. The plasma alanine aminotransferase (ALT) and aspartate aminotransferase (AST) activities were assayed and the isolated livers were evaluated for histopathological changes. The dose-toxicity relationships of single treatment of PM or co-treatment of LPS were investigated comparatively to elucidate the idiosyncratic hepatotoxicity of PM. The results showed that no significant alterations of plasma ALT and AST activities were observed in the groups of solo-administration of LPS (2.8 mg·kg(-1), i.v.) or different dosage (18.9, 37.8 and 75.6 g·kg(-1), i.g.) of PM, compared to normal control group (P > 0.05); while significant elevations were observed in the co-administration groups of PM and LPS. Treatment with LPS alone caused slight infiltration of inflammatory cells in portal area but no evident hepatocytes injury. Co-treatment with LPS and PM (75.6 g·kg(-1), i.g.) caused hepatocyte focal necrosis, loss of central vein intima and a large number of inflammatory cell infiltration in portal areas. When further reduce the dosage of PM, significant increases of plasma ALT and AST activities (P < 0.05) were still observed in co-administration groups of LPS and PM (1.08 or 2.16 g·kg(-1)), but not in LPS or PM solo-administration groups. Nevertheless, the co-treatment of low dosage of PM (0.54 g·kg(-1)) with LPS did not induce any alteration of plasma ALT and AST. In conclusion, intragastric administration with 75.6 g·kg(-1) of PM did not induce liver injury in normal rats model; while the 2 folds of clinical equivalent dose of PM (1.08 g·kg(-1)) could result in liver injury in the LPS-based idiosyncratic hepatotoxicity model, which could be used to evaluate the idiosyncratic hepatotoxicity of PM. PMID:25924471

  17. The Serum Resistome of a Globally Disseminated Multidrug Resistant Uropathogenic Escherichia coli Clone

    PubMed Central

    Phan, Minh-Duy; Peters, Kate M.; Sarkar, Sohinee; Lukowski, Samuel W.; Allsopp, Luke P.; Moriel, Danilo Gomes; Achard, Maud E. S.; Totsika, Makrina; Marshall, Vikki M.; Upton, Mathew; Beatson, Scott A.; Schembri, Mark A.

    2013-01-01

    Escherichia coli ST131 is a globally disseminated, multidrug resistant clone responsible for a high proportion of urinary tract and bloodstream infections. The rapid emergence and successful spread of E. coli ST131 is strongly associated with antibiotic resistance; however, this phenotype alone is unlikely to explain its dominance amongst multidrug resistant uropathogens circulating worldwide in hospitals and the community. Thus, a greater understanding of the molecular mechanisms that underpin the fitness of E. coli ST131 is required. In this study, we employed hyper-saturated transposon mutagenesis in combination with multiplexed transposon directed insertion-site sequencing to define the essential genes required for in vitro growth and the serum resistome (i.e. genes required for resistance to human serum) of E. coli EC958, a representative of the predominant E. coli ST131 clonal lineage. We identified 315 essential genes in E. coli EC958, 231 (73%) of which were also essential in E. coli K-12. The serum resistome comprised 56 genes, the majority of which encode membrane proteins or factors involved in lipopolysaccharide (LPS) biosynthesis. Targeted mutagenesis confirmed a role in serum resistance for 46 (82%) of these genes. The murein lipoprotein Lpp, along with two lipid A-core biosynthesis enzymes WaaP and WaaG, were most strongly associated with serum resistance. While LPS was the main resistance mechanism defined for E. coli EC958 in serum, the enterobacterial common antigen and colanic acid also impacted on this phenotype. Our analysis also identified a novel function for two genes, hyxA and hyxR, as minor regulators of O-antigen chain length. This study offers novel insight into the genetic make-up of E. coli ST131, and provides a framework for future research on E. coli and other Gram-negative pathogens to define their essential gene repertoire and to dissect the molecular mechanisms that enable them to survive in the bloodstream and cause disease. PMID:24098145

  18. The serum resistome of a globally disseminated multidrug resistant uropathogenic Escherichia coli clone.

    PubMed

    Phan, Minh-Duy; Peters, Kate M; Sarkar, Sohinee; Lukowski, Samuel W; Allsopp, Luke P; Gomes Moriel, Danilo; Achard, Maud E S; Totsika, Makrina; Marshall, Vikki M; Upton, Mathew; Beatson, Scott A; Schembri, Mark A

    2013-01-01

    Escherichia coli ST131 is a globally disseminated, multidrug resistant clone responsible for a high proportion of urinary tract and bloodstream infections. The rapid emergence and successful spread of E. coli ST131 is strongly associated with antibiotic resistance; however, this phenotype alone is unlikely to explain its dominance amongst multidrug resistant uropathogens circulating worldwide in hospitals and the community. Thus, a greater understanding of the molecular mechanisms that underpin the fitness of E. coli ST131 is required. In this study, we employed hyper-saturated transposon mutagenesis in combination with multiplexed transposon directed insertion-site sequencing to define the essential genes required for in vitro growth and the serum resistome (i.e. genes required for resistance to human serum) of E. coli EC958, a representative of the predominant E. coli ST131 clonal lineage. We identified 315 essential genes in E. coli EC958, 231 (73%) of which were also essential in E. coli K-12. The serum resistome comprised 56 genes, the majority of which encode membrane proteins or factors involved in lipopolysaccharide (LPS) biosynthesis. Targeted mutagenesis confirmed a role in serum resistance for 46 (82%) of these genes. The murein lipoprotein Lpp, along with two lipid A-core biosynthesis enzymes WaaP and WaaG, were most strongly associated with serum resistance. While LPS was the main resistance mechanism defined for E. coli EC958 in serum, the enterobacterial common antigen and colanic acid also impacted on this phenotype. Our analysis also identified a novel function for two genes, hyxA and hyxR, as minor regulators of O-antigen chain length. This study offers novel insight into the genetic make-up of E. coli ST131, and provides a framework for future research on E. coli and other Gram-negative pathogens to define their essential gene repertoire and to dissect the molecular mechanisms that enable them to survive in the bloodstream and cause disease. PMID:24098145

  19. MiR-146b Mediates Endotoxin Tolerance in Human Phagocytes

    PubMed Central

    Renzi, Tiziana Ada; Rubino, Marcello; Gornati, Laura; Garlanda, Cecilia; Locati, Massimo; Curtale, Graziella

    2015-01-01

    A proper regulation of the innate immune response is fundamental to keep the immune system in check and avoid a chronic status of inflammation. As they act as negative modulators of TLR signaling pathways, miRNAs have been recently involved in the control of the inflammatory response. However, their role in the context of endotoxin tolerance is just beginning to be explored. We here show that miR-146b is upregulated in human monocytes tolerized by LPS, IL-10, or TGF? priming and demonstrate that its transcription is driven by STAT3 and RUNX3, key factors downstream of IL-10 and TGF? signaling. Our study also found that IFN?, known to revert LPS tolerant state, inhibits miR-146b expression. Finally, we provide evidence that miR-146b levels have a profound effect on the tolerant state, thus candidating miR-146b as a molecular mediator of endotoxin tolerance. PMID:26451077

  20. Rapid detection of contaminated intravenous fluids using the Limulus in vitro endotoxin assay.

    PubMed

    Jorgensen, J H; Smith, R F

    1973-10-01

    Intravenous fluids and administration sets may become contaminated with gram-negative bacteria during use and result in a life-threatening situation to the patient. The Limulus in vitro assay for endotoxin was used in two patients whose parenteral fluids had become contaminated with Pseudomonas aeruginosa. This test allowed rapid detection of the contaminated intravenous fluids and demonstrated a concomitant endotoxemia in both patients. The same strains of pseudomon were subsequently cultured from each patient's blood, intravenous catheter tip, and parenteral fluid and administration set. A different serotype of pseudomonas was unique to each patient, indicating two separate and unrelated cases of accidental contamination of the administration sets. Endotoxin-like activity was also demonstrated from several brands of commercial human serum albumin, which may contribute low-level activity detectable by the Limulus assay. PMID:4584590

  1. The role of spermidine/spermine N1-acetyltransferase in endotoxin-induced acute kidney injury.

    PubMed

    Zahedi, Kamyar; Barone, Sharon; Kramer, Debora L; Amlal, Hassane; Alhonen, Leena; Jänne, Juhani; Porter, Carl W; Soleimani, Manoocher

    2010-07-01

    The expression of catabolic enzymes spermidine/spermine N(1)-acetyltransferase (SSAT) and spermine oxidase (SMO) increases after ischemic reperfusion injury. We hypothesized that polyamine catabolism is upregulated and that this increase in catabolic response contributes to tissue damage in endotoxin-induced acute kidney injury (AKI). SSAT mRNA expression peaked at threefold 24 h following LPS injection and returned to background levels by 48 h. The activity of SSAT correlated with its mRNA levels. The expression of SMO also increased in the kidney after LPS administration. Serum creatinine levels increased significantly at approximately 15 h, peaking by 24 h, and returned to background levels by 72 h. To test the role of SSAT in endotoxin-induced AKI, we injected wild-type (SSAT-wt) and SSAT-deficient (SSAT-ko) mice with LPS. Compared with SSAT-wt mice, the SSAT-ko mice subjected to endotoxic-AKI had less severe kidney damage as indicated by better preservation of kidney function. The role of polyamine oxidation in the mediation of kidney injury was examined by comparing the severity of renal damage in SSAT-wt mice treated with MDL72527, an inhibitor of both polyamine oxidase and SMO. Animals treated with MDL72527 showed significant protection against endotoxin-induced AKI. We conclude that increased polyamine catabolism through generation of by-products of polyamine oxidation contributes to kidney damage and that modulation of polyamine catabolism may be a viable approach for the treatment of endotoxin-induced AKI. PMID:20392931

  2. Allergens and endotoxin on mothers' mattresses and total immunoglobulin E in cord blood of neonates.

    PubMed

    Heinrich, J; Bolte, G; Hölscher, B; Douwes, J; Lehmann, I; Fahlbusch, B; Bischof, W; Weiss, M; Borte, M; Wichmann, H E

    2002-09-01

    The current authors examined whether mite and cat allergen and bacterial endotoxin levels in dust of the mothers' mattresses were associated with cord blood immunoglobulin (Ig)E (CB-IgE) levels in newborns. Data from 1,332 term and normal weight neonates, from an ongoing birth cohort study, influences of life-style related factors on the immune system and the development of allergies in childhood (LISA), with complete information on exposure to biocontaminants in mattress dust and CB-IgE were analysed. Two thirds of CB-IgE were undetectable (<0.35 kU x L(-1)). Thus, 0.35 and 0.45 kU x L(-1) (4th quartile) were chosen as cut-offs. Nonparametric smoothing (generalised additive models) showed statistically significant confounder-adjusted associations between elevated CB-IgE levels (> or = 0.45 kU x L(-1)) and log-transformed exposures to cat (linear), mite (inverse u-shaped), and endotoxin (u-shaped). After adjustment for covariables, elevated CB-IgE levels (logistic regression using the 1st-4th quartiles of exposure) were positively associated with high cat-allergen exposure and medium exposure to mite allergen, but were inversely associated with exposure to endotoxin. The associations were similar, but somewhat weaker, when 0.35 kU x L(-1) was used as cut-off. These results, showing an association between prenatal allergen and endotoxin exposures and immunoglobulin E production, suggest that the development of foetal immune responses may be affected. PMID:12358337

  3. ToxinSensorTM Chromogenic LAL Endotoxin Assay Kit Cat. No. L00350, L00350C

    E-print Network

    Lebendiker, Mario

    LAL Reagent Water. Since the LAL-endotoxin reaction is pH dependent, the pH value of the mixture AND EQUIPMENT NOT PROVIDED 1. Sodium hydroxide, 0.1 N, dissolved in LAL Reagent Water, for pH adjustment. 2. Hydrochloric acid, 0.1 N, diluted in LAL Reagent Water, for pH adjustment. 3. Water bath or heating block set

  4. PATHOGENIC ESCHERICHIA COLI

    EPA Science Inventory

    Escherichia coli is a bacterial species which inhabits the gastrointestinal tract of man and warm-blooded animals. Because of the ubiquity of this bacterium in the intestinal flora, it serves as an important indicator organism of fecal contamination. E. coli, aside from serving a...

  5. [The comparative characteristics of preparations of Yersinia pestis capsular antigen F1 obtained from producer strains with different lipopolysaccharide structures].

    PubMed

    Gremiakova, T A; Stepanshina, V N; Negri?, V F; Korobova, O V; Anisimov, G A; Apollonin, A V; Likhoded, V G

    1994-01-01

    The main protective antigen of the causative agent of plague is capsular antigen F1. The preparations of this antigen isolated from Y.pestis strain EV are characterized by a high content of polysaccharide chains of endotoxins. This can be avoided by using R-variants of bacteria as producers. In this work the comparative study of the preparations of antigen F1 obtained from Y.pestis strain EV, Escherichia coli producer strain HB101 pFS1 with the complete structure of LPS and Salmonella minnesota producer strain Re595 pFS1 with maximally reduced LPS has been made. As revealed in this study, the physico-chemical properties of these preparations (the isoelectric point, electrophoretic mobility, the molecular weight of subunits) are identical. The preparation of antigen F1 obtained from S.minnesota has been found to give the highest yield and to have the lowest content of polysaccharide admixtures. This preparation has proved to possess the maximal protective potency, which may be linked with the adjuvant and immunogenic activity of microadmixtures of glycolipid Re, contained in F1. PMID:7941851

  6. Recombinant HDL (Milano) protects endotoxin-challenged rats from multiple organ injury and dysfunction.

    PubMed

    Zhang, Xinbo; Wang, Luya; Chen, Baosheng

    2015-01-01

    Endotoxemia, the systemic inflammatory host response to infection, leads to severe septic shock and multiple organ injury and dysfunction syndrome (MOPS), which cause mortality. Apolipoprotein A-IMilano (apoAIM), a naturally occurring cysteine mutant of apoAI with dimers as its effective form, showed an enhanced cardiovascular protective activity compared with wild-type apoAI (apoAIwt). To investigate the role of recombinant high-density lipoprotein (rHDL) reconstituted with apoAIM (rHDLM) on endotoxemia and MOPS, we examined the anti-inflammatory, anti-oxidant, and protective effects of this cysteine mutant against organ injury in endotoxin-challenged rat models compared with rHDLwt. In the present study, we demonstrated for the first time that pretreatment with rHDLM significantly attenuated liver and renal dysfunction and histopathological features of lung injury in endotoxin-challenged endotoxemia rats. Administration of rHDLM to endotoxemia rats dramatically suppressed proinflammatory cytokines and adhesion molecule increase in tumor necrosis factor ?, interleukin 1?, interleukin 6, and intercellular adhesion molecule 1. In addition, rHDLM pretreatment inhibited lipid peroxidation and enhanced total antioxidant capacity in vivo. In comparison with rHDLwt, rHDLM showed enhanced capacity on anti-inflammatory and anti-oxidant functions. In summary, administration of rHDLM protected endotoxin-challenged endotoxemia and MOPS through enhanced anti-inflammatory and anti-oxidant properties. PMID:25205725

  7. Modeling Endotoxin-Induced Systemic Inflammation Using an Indirect Response Approach

    PubMed Central

    Foteinou, P.T.; Calvano, S.E.; Lowry, S.F.; Androulakis, I.P.

    2011-01-01

    A receptor mediated model of endotoxin-induced human inflammation is proposed. The activation of the innate immune system in response to the endotoxin stimulus involves the interaction between the extracellular signal and critical receptors driving downstream signal transduction cascades leading to transcriptional changes. We explore the development of an in silico model that aims at coupling extracellular signals with essential transcriptional responses through a receptor mediated indirect response model. The model consists of eight (8) variables and is evaluated in a series of biologically relevant scenarios indicative of the non–linear behavior of inflammation. Such scenarios involve a self-limited response where the inflammatory stimulus is cleared successfully; a persistent infectious response where the inflammatory instigator is not eliminated, leading to an aberrant inflammatory response, and finally, a persistent non-infectious inflammatory response that can be elicited under an overload of the pathogen-derived product; as such high dose of the inflammatory insult can disturb the dynamics of the host response leading to an unconstrained inflammatory response. Finally, the potential of the model is demonstrated by analyzing scenarios associated with endotoxin tolerance and potentiation effects. PMID:18840451

  8. Factors influencing endotoxin concentrations on cotton grown in hot, humid environments: a two year study.

    PubMed Central

    DeLucca, A J; Shaffer, G P

    1989-01-01

    Cotton leaf, bract, fibre from opened bolls, and soil samples were collected weekly during two growing seasons (1984, 1985). Total and Gram negative bacterial populations were determined for each sample. Representative bacterial isolates were identified and endotoxin concentrations determined. For both years total and Gram negative bacterial populations on all sample types remained relatively stable until plant senescence. Afterwards, until plant death by frost, counts for all samples increased dramatically. Enterobacter agglomerans was the predominant species on leaf and bract, whereas the "all other" Gram negative bacterial species classification was the most common on fibre, with E agglomerans a close second. Senescence affected the occurrence of the species isolated. Statistical analysis partitioned by sample type showed strong correlations between endotoxin concentrations and certain bacteriological and environmental variables. The data suggest that in hot, humid environments the concentration of endotoxin on cotton leaf, bract, and fibre may be predicted by total and Gram negative bacterial counts, daily high temperature, and week after plant germination. PMID:2611164

  9. Comparison of agents producing a neutrophilic leukocytosis in man. Hydrocortisone, prednisone, endotoxin, and etiocholanolone.

    PubMed Central

    Dale, D C; Fauci, A S; Guerry D, I V; Wolff, S M

    1975-01-01

    To study the potential application of glucocorticosteroid administration for the measurement of the bone marrow neutrophil reserve response, blood neutrophil count changes were measured in normal subjects after the administration of intravenous hydrocortisone (25, 50, 100, 200, and 400 mg) and oral prednisone (5, 10, 20, 40, and 80 mg). The upper three doses of both steroids increased the blood neutrophil count by approximately 4,000 cells/mm3. The neutrophilia occurring after hydrocortisone (200 mg) and/or prednisone (40 mg) was compared with that observed after endotoxin (0.8 ng/kg) and etiocholanolone (0.1 mg/kg) in 14 normal subjects, 7 patients with Wegener's granulomatosis on cyclophosphamide therapy and 10 patients with chronic idiopathic neutropenia. The normal responses (mean increase of blood neutrophils/mm3 above base line +/- 1 SEM) were: hydrocortisone 4,220 +/- 320, prednisone 4,610 +/- 360, endotoxin 6,060 +/- 880, and etiocholanolone 3,780 +/- 440. In the patient studies, etiocholanolone gave the smallest mean responses, but, in general, the results were similar for all agents. These data indicate that these glucocorticosteroids can be used as equivalent agents to endotoxin and etiocholanolone for measuring the neutrophil reserve response. PMID:1159089

  10. Escherichia coli virulence factors.

    PubMed

    Mainil, Jacques

    2013-03-15

    Escherichia coli was described in 1885 by a German pediatrician, Theodor Escherich, in the faeces of a child suffering diarrhoea. In 1893, a Danish veterinarian postulated that the E. coli species comprises different strains, some being pathogens, others not. Today the E. coli species is subdivided into several pathogenic strains causing different intestinal, urinary tract or internal infections and pathologies, in animal species and in humans. Since this congress topic is the interaction between E. coli and the mucosal immune system, the purpose of this manuscript is to present different classes of adhesins (fimbrial adhesins, afimbrial adhesins and outer membrane proteins), the type 3 secretion system, and some toxins (oligopeptide, AB, and RTX pore-forming toxins) produced by E. coli, that can directly interact with the epithelial cells of the intestinal, respiratory and urinary tracts. PMID:23083938

  11. Exposure to airborne culturable microorganisms and endotoxin in two Italian poultry slaughterhouses.

    PubMed

    Paba, Emilia; Chiominto, Alessandra; Marcelloni, Anna Maria; Proietto, Anna Rita; Sisto, Renata

    2014-01-01

    Even if slaughterhouses' workers handle large amounts of organic material and are potentially exposed to a wide range of biological agents, relatively little and not recent data are available. The main objective of this study was to characterize indoor concentrations of airborne bacteria, fungi, and endotoxin mod = Im (endotoxin?Gram-negative*plant*filter) in two Italian poultry slaughterhouses. Air samples near air handling units inlets were also collected. Since there are not standardized protocols for endotoxin sampling and extraction procedures, an additional aim of the study was to compare the extraction efficiency of three different filter.. The study was also aimed at determining the correlation between concentrations of Gram-negative bacteria and endotoxin. In Plant A bacterial levels ranged from 17.5 to 2.6×10(3) CFU/m3. The highest concentrations were observed in evisceration area of chickens, between the automatic detachment of the neck and washing offal, and near birds coupling before hair-chilling. The highest mean value of Gram-negative (266.5 CFU/m3) was found near the washing offal of turkeys. In Plant B bacterial concentration ranged from 35 to 8×10(3) CFU/m3. The highest concentration. with the highest value of Gram-negative (248 CFU/m3), was found after defeathering. Fungal concentrations were overall lower than those found for bacteria (range: 0-205 CFU/m3 in Plant A and 0-146.2 CFU/m3 in Plant B). The microbial flora was dominated by Gram-negative and coagulase-negative staphylococci for bacteria and by species belonging to Cladosporium, Penicillium and Aspergillus genera for molds. The highest endotoxin concentrations were measured in washing offal for Plant A (range: 122.7-165.9 EU/m3) and after defeathering for Plant B (range: 0.83-38.85 EU/m3). In this study airborne microorganisms concentrations were lower than those found in similar occupational settings and below the occupational limits proposed by some authors. However, these microorganisms may exert adverse effects on exposed workers, in particular for those engaged in the early slaughtering stages, as evidenced by the presence of pathogenic species. The detection of pathogenic bacteria near AHU inlet may constitute a risk to public health and environmental pollution. PMID:24467310

  12. Genomic and Phenomic Study of Mammary Pathogenic Escherichia coli.

    PubMed

    Blum, Shlomo E; Heller, Elimelech D; Sela, Shlomo; Elad, Daniel; Edery, Nir; Leitner, Gabriel

    2015-01-01

    Escherichia coli is a major etiological agent of intra-mammary infections (IMI) in cows, leading to acute mastitis and causing great economic losses in dairy production worldwide. Particular strains cause persistent IMI, leading to recurrent mastitis. Virulence factors of mammary pathogenic E. coli (MPEC) involved pathogenesis of mastitis as well as those differentiating strains causing acute or persistent mastitis are largely unknown. This study aimed to identify virulence markers in MPEC through whole genome and phenome comparative analysis. MPEC strains causing acute (VL2874 and P4) or persistent (VL2732) mastitis were compared to an environmental strain (K71) and to the genomes of strains representing different E. coli pathotypes. Intra-mammary challenge in mice confirmed experimentally that the strains studied here have different pathogenic potential, and that the environmental strain K71 is non-pathogenic in the mammary gland. Analysis of whole genome sequences and predicted proteomes revealed high similarity among MPEC, whereas MPEC significantly differed from the non-mammary pathogenic strain K71, and from E. coli genomes from other pathotypes. Functional features identified in MPEC genomes and lacking in the non-mammary pathogenic strain were associated with synthesis of lipopolysaccharide and other membrane antigens, ferric-dicitrate iron acquisition and sugars metabolism. Features associated with cytotoxicity or intra-cellular survival were found specifically in the genomes of strains from severe and acute (VL2874) or persistent (VL2732) mastitis, respectively. MPEC genomes were relatively similar to strain K-12, which was subsequently shown here to be possibly pathogenic in the mammary gland. Phenome analysis showed that the persistent MPEC was the most versatile in terms of nutrients metabolized and acute MPEC the least. Among phenotypes unique to MPEC compared to the non-mammary pathogenic strain were uric acid and D-serine metabolism. This study reveals virulence factors and phenotypic characteristics of MPEC that may play a role in pathogenesis of E. coli mastitis. PMID:26327312

  13. Genomic and Phenomic Study of Mammary Pathogenic Escherichia coli

    PubMed Central

    Blum, Shlomo E.; Heller, Elimelech D.; Sela, Shlomo; Elad, Daniel; Edery, Nir; Leitner, Gabriel

    2015-01-01

    Escherichia coli is a major etiological agent of intra-mammary infections (IMI) in cows, leading to acute mastitis and causing great economic losses in dairy production worldwide. Particular strains cause persistent IMI, leading to recurrent mastitis. Virulence factors of mammary pathogenic E. coli (MPEC) involved pathogenesis of mastitis as well as those differentiating strains causing acute or persistent mastitis are largely unknown. This study aimed to identify virulence markers in MPEC through whole genome and phenome comparative analysis. MPEC strains causing acute (VL2874 and P4) or persistent (VL2732) mastitis were compared to an environmental strain (K71) and to the genomes of strains representing different E. coli pathotypes. Intra-mammary challenge in mice confirmed experimentally that the strains studied here have different pathogenic potential, and that the environmental strain K71 is non-pathogenic in the mammary gland. Analysis of whole genome sequences and predicted proteomes revealed high similarity among MPEC, whereas MPEC significantly differed from the non-mammary pathogenic strain K71, and from E. coli genomes from other pathotypes. Functional features identified in MPEC genomes and lacking in the non-mammary pathogenic strain were associated with synthesis of lipopolysaccharide and other membrane antigens, ferric-dicitrate iron acquisition and sugars metabolism. Features associated with cytotoxicity or intra-cellular survival were found specifically in the genomes of strains from severe and acute (VL2874) or persistent (VL2732) mastitis, respectively. MPEC genomes were relatively similar to strain K-12, which was subsequently shown here to be possibly pathogenic in the mammary gland. Phenome analysis showed that the persistent MPEC was the most versatile in terms of nutrients metabolized and acute MPEC the least. Among phenotypes unique to MPEC compared to the non-mammary pathogenic strain were uric acid and D-serine metabolism. This study reveals virulence factors and phenotypic characteristics of MPEC that may play a role in pathogenesis of E. coli mastitis. PMID:26327312

  14. The role of endotoxin, TNF-?, and IL-6 in inducing the state of growth hormone insensitivity

    PubMed Central

    Wang, Ping; Li, Ning; Li, Jie-Shou; Li, Wei-Qin

    2002-01-01

    AIM: Critical illnesses such as sepsis, trauma, and burns cause a growth hormone insensitivity, which leads to an increased negative nitrogen balance. Endotoxin is generously released into blood under these conditions and stimulates the production of proinflammatory cytokines such as TNF-?, IL-6, and IL-1, which may play a very important role in inducing the growth hormone insensitivity. The objective of this current study was to investigate the role of endotoxin, TNF-? and IL-6 in inducing the growth hormone insensitivity at the receptor and post-receptor levels. METHODS: Spague-Dawley rats were injected with endotoxin, TNF-?, and IL-6, respectively and part of rats injected with endotoxin was treated with exogenous somatotropin simultaneously. All rats were killed at different time points. The expression of IGF-I, GHR, SOCS-3 and ?-actin mRNA in the liver was detected by RT-PCR and the GH levels were measured by radioimmunoassay, the levels of TNF-? and IL-6 were detected by ELISA. RESULTS: There was no significant difference in serous GH levels between experimental group and control rats after endotoxin injection, however, liver IGF-I mRNA expression had been obviously down-regulated in endotoxemic rats. Liver GHR mRNA expression also had a predominant down-regulation after endotoxin injection. The lowest regulation of liver IGF-I mRNA expression occurred at 12 h after LPS injection, being decreased by 53% compared with control rats. For GHR mRNA expression, the lowest expression occurred at 8 h and had a 81% decrease. Although SOCS-3 mRNA was weakly expressed in control rats, it was strongly up-regulated after LPS injection and had a 7.84 times increase compared with control rats. Exogenous GH could enhance IGF-I mRNA expression in control rats, but it did fail to prevent the decline in IGF-I mRNA expression in endotoxemic rats. Endotoxin stimulated the production of TNF-? and IL-6, and the elevated IL-6 levels was shown a positive correlation with increased SOCS-3 mRNA expression. The liver GHR mRNA expression was obviously down-regulated after TNF-? iv injection and had a 40% decrease at 8 h, but the liver SOCS-3 mRNA expression was the 4.94 times up-regulation occurred at 40 min after IL-6 injection. CONCLUSION: The growth hormone insensitivity could be induced by LPS injection, which was associated with down-regulated GHR mRNA expression at receptor level and with up-regulated SOCS-3 mRNA expression at post-receptor level. The in vivo biological activities of LPS were mediated by TNF-? and IL-6 indirectly, and TNF-? and IL-6 may exert their effects on the receptor and post-receptor levels respectively. PMID:12046086

  15. Comparison of the Transport of Tetracycline-Resistant and Tetracycline-Susceptible Escherichia coli Isolated from Lake Michigan.

    PubMed

    Walczak, Jacob J; Bardy, Sonia L; Feriancikova, Lucia; Xu, Shangping

    2011-11-01

    It was recently reported that tetracycline could enhance the mobility of manure-derived Escherichia coli within saturated porous media (Walczak et al. (Water Research 45:1681-1690, 2011)). It was also shown, however, that E. coli from various sources could display marked variation in their mobility (Bolster et al. (Journal of Environmental Quality 35:1018-1025, 2009)). The focus of this research was to examine if the observed difference in the mobility of manure-derived tetracycline-resistant (tet(R)) and tetracycline-susceptible (tet(S)) E. coli strains was source-dependent. Specifically, E. coli were isolated from Lake Michigan, and the influence of tetracycline resistance on Lake Michigan-derived E. coli was investigated through column transport experiments. Additionally, a variety of cell morphology and surface properties were determined and related to the observed bacterial transport behavior. Our experimental results showed that, consistent with previous observations, the deposition rate coefficients of the tet(R)E. coli strain was ~20-100% higher than those of the tet(S)E. coli strain. The zeta potential of the tet(R)E. coli cells was ~25 mV more negative than the tet(S)E. coli cells. Because the surfaces of the E. coli cells and the quartz sands were negatively charged, the repulsive electrostatic double-layer interaction between the tet(R)E. coli cells and the quartz sands was stronger, and the mobility of the tet(R)E. coli cells in the sand packs was thus higher. The tet(R)E. coli cells were also more hydrophilic than the tet(S)E. coli cells. Results from migration to hydrocarbon phase (MATH) tests showed that about ~35% more tet(S)E. coli cells partitioned to the hydrocarbon phase. As it was previously shown that cell hydrophobicity could enhance the attachment of bacterial cells to quartz sand, the difference in cell hydrophobicity could also have contributed to the observed higher mobility of the tet(R)E. coli cells. The size of the tet(R) and tet(S)E. coli cells were similar, suggesting that the observed difference in their mobility was not size-related. Characterization of cell surface properties also showed that tet(R) and tetS E. coli cells differed slightly in cell-bound lipopolysaccharide contents and had distinct outer membrane protein profiles. Such difference could alter cell surface properties which in turn led to changes in cell mobility. PMID:22121301

  16. Airborne endotoxin predicts symptoms in non-mouse-sensitized technicians and research scientists exposed to laboratory mice.

    PubMed

    Pacheco, Karin A; McCammon, Charles; Liu, Andrew H; Thorne, Peter S; O'Neill, Marsha E; Martyny, John; Newman, Lee S; Hamman, Richard F; Rose, Cecile S

    2003-04-01

    Research scientists, laboratory technicians, and animal handlers who work with animals frequently report respiratory and skin symptoms from exposure to laboratory animals (LA). However, on the basis of prick skin tests or RASTs, only half are sensitized to LA. We hypothesized that aerosolized endotoxin from mouse work is responsible for symptoms in nonsensitized workers. We performed a cross-sectional study of 269/310 (87%) workers at a research institution. Subjects completed a questionnaire and underwent prick skin tests (n = 254) or RASTs (n = 16) for environmental and LA allergens. We measured airborne mouse allergen and endotoxin in the animal facility and in research laboratories. Of 212 workers not sensitized to mice, 34 (16%) reported symptoms compared with 26 (46%) of mouse-sensitized workers (p < 0.001). Symptomatic workers were more likely to be atopic, regardless of mouse sensitization status. Symptomatic non-mouse-sensitized workers spent more time performing animal experiments in the animal facility (p = 0.0001) and in their own laboratories (p < 0.0001) and had higher daily endotoxin exposure (p = 0.008) compared with asymptomatic coworkers. In a multivariate model, daily endotoxin exposure most strongly predicted symptoms to mice in non-mouse-sensitized workers (odds ratio = 30.8, p = 0.003). We conclude that airborne endotoxin is associated with respiratory symptoms to mice in non-mouse-sensitized scientists and technicians. PMID:12663339

  17. Determination of endotoxins on hypodermic needles by means of a chromogenic Limulus amoebocyte lysate assay. Development of a test model.

    PubMed

    Vanhaecke, E; Pijck, J

    1986-10-01

    A test model was developed in order to describe the determination of endotoxins on hypodermic needles in a reliable and reproducible manner. As in all in-vitro experiments one has to be very careful about extrapolating data to in-vivo situations. However by choosing a hydrophilic (Salmonella typhimurium ATCC 14028) and a hydrophobic bacterium (Acinetobacter calcoaceticus var. anitratus RR 8212/113), one could hope to obtain a quite representative idea about the extraction of contaminating gram-negative micro-organisms. Using the proposed extraction procedure and a chromogenic LAL assay as detection system, it was possible to achieve a quantitative idea about the extraction of endotoxins on hypodermic needles. Extracting needles at 19 degrees C during 83 to 98 min produced the highest yield as to the detection of endotoxins from hydrophilic strains. For the detection of endotoxins from hydrophobic strains, the highest yield values were obtained when the extraction was performed at temperatures between 64 and 80 degrees C during 96 to 120 min. However it seems necessary to perform the extractions at least three times in order to obtain reproducible results. In conclusion, using the extraction procedure as described, it is possible to measure endotoxin-like activity, on the inner and outer surface of hypodermic needles in a simple but accurate way, using water as extraction fluid and a chromogenic Limulus Amoebocyte Lysate assay as detection system. PMID:3101323

  18. Ineffectiveness of Vi and chemically treated endotoxins as typhoid vaccines in mice challenged with a Salmonella typhosa-Salmonella typhimurium hybrid.

    PubMed Central

    Diena, B B; Ryan, A; Wallace, R; Ashton, F E; Johnson, E M; Baron, L S

    1975-01-01

    Purified Vi antigen, acetic anthydride-treated Salmonella typhosa endotoxin, and potassium methylate-treated S. typhosa endotoxin employed as vaccines in Swiss white mice failed to protect these animals against challenge with a virulent S. typhimurium hybrid expressing S. typhosa antigens. PMID:1107227

  19. Associations between endotoxin-induced metabolic changes and temperament in Brahman bulls

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The influence of temperament on the alteration of metabolic parameters in response to a lipopolysaccharide (LPS) challenge was investigated. Brahman bulls were selected for this study based on temperament score. Bulls were fitted with indwelling jugular catheters for serial sampling to evaluate peri...

  20. Lipopolysaccharide-induced elaboration of interleukin 1 by human monocytes: use for detection of lipopolysaccharide in serum and the influence of serum-lipopolysaccharide interactions.

    PubMed

    Northoff, H; Glück, D; Wölpl, A; Kubanek, B; Galanos, C

    1987-01-01

    An assay of interleukin 1 (IL-1) production by human monocytes was used to detect minute amounts of bacterial lipopolysaccharide (LPS) in sera or serum components designed for use in experiments or for injection into humans. Elaboration of IL-1 is a more sensitive criterion for the presence of LPS than is the rabbit pyrogenicity assay, and contamination of a given solution with LPS can be semiquantitatively determined by comparison with a standard. Interaction of (exogenously added) LPS with serum interferes with the recognition of LPS by monocytes but in a manner different from that encountered in the limulus test. Recognition of LPS by monocytes was not affected by the presence of naturally occurring antibodies to LPS. With use of IL-1 elaboration as an indicator, the presence of functionally active LPS in the sera of some patients with sepsis could be demonstrated. PMID:3500494

  1. The impact of IL-1 modulation on the development of lipopolysaccharide-induced cognitive dysfunction

    E-print Network

    2010-01-01

    after LPS, primarily via activation of toll-like receptorToll-like receptor 4 (TLR4)-deficient mice are hyporesponsive to lipopolysaccharide: evidence for TLR4 as the LpsLPS: lipopolysaccharide; NF: nuclear factor; PBS: phosphate-buffered saline; qPCR: quantitative polymerase chain reaction; TLR: toll-like receptor;

  2. Computer Simulation of the Rough Lipopolysaccharide Membrane of Pseudomonas Aeruginosa

    SciTech Connect

    Lins, Roberto D.; Straatsma, TP

    2001-08-01

    Lipopolysaccharides (LPS) form the major constituent of the outer membrane of Gram-negative bacteria, and are believed to play a key role in processes that govern microbial metal binding, microbial adsorption to mineral surfaces, and microbe mediated oxidation/reduction reactions at the bacterial exterior surface. A computational modeling capability is being developed for the study of geochemical reactions at the outer bacterial envelope of Gram-negative bacteria. The understanding of these mechanisms is crucial for the development of successful environmental bioremediation strategies. A molecular model for the rough LPS of Pseudomonas aeruginosa has been designed based on available experimentally determined structural information.

  3. Lipopolysaccharide Disrupts the Milk-Blood Barrier by Modulating Claudins in Mammary Alveolar Tight Junctions

    PubMed Central

    Kobayashi, Ken; Oyama, Shoko; Numata, Atsushi; Rahman, Md. Morshedur; Kumura, Haruto

    2013-01-01

    Mastitis, inflammation of the mammary gland, is the most costly common disease in the dairy industry, and is caused by mammary pathogenic bacteria, including Escherichia coli. The bacteria invade the mammary alveolar lumen and disrupt the blood-milk barrier. In normal mammary gland, alveolar epithelial tight junctions (TJs) contribute the blood-milk barrier of alveolar epithelium by blocking the leakage of milk components from the luminal side into the blood serum. In this study, we focused on claudin subtypes that participate in the alveolar epithelial TJs, because the composition of claudins is an important factor that affects TJ permeability. In normal mouse lactating mammary glands, alveolar TJs consist of claudin-3 without claudin-1, -4, and -7. In lipopolysaccharide (LPS)-induced mastitis, alveolar TJs showed 2-staged compositional changes in claudins. First, a qualitative change in claudin-3, presumably caused by phosphorylation and participation of claudin-7 in alveolar TJs, was recognized in parallel with the leakage of fluorescein isothiocyanate-conjugated albumin (FITC-albumin) via the alveolar epithelium. Second, claudin-4 participated in alveolar TJs with claudin-3 and claudin-7 12 h after LPS injection. The partial localization of claudin-1 was also observed by immunostaining. Coinciding with the second change of alveolar TJs, the severe disruption of the blood-milk barrier was recognized by ectopic localization of ?-casein and much leakage of FITC-albumin. Furthermore, the localization of toll-like receptor 4 (TLR4) on the luminal side and NF?B activation by LPS was observed in the alveolar epithelial cells. We suggest that the weakening and disruption of the blood-milk barrier are caused by compositional changes of claudins in alveolar epithelial TJs through LPS/TLR4 signaling. PMID:23626786

  4. Monoclonal antibody analysis of lipopolysaccharide from Neisseria gonorrhoeae and Neisseria meningitidis.

    PubMed Central

    Apicella, M A; Bennett, K M; Hermerath, C A; Roberts, D E

    1981-01-01

    A hybridoma produced by the polyethylene glycol fusion of the NS-1 variant of the P3x63Ag8 BALB/c plasmacytoma to splenocytes harvested from a BALB/c mouse immunized with whole gonococci was found to be producing antibody to a common region on gonococcal lipopolysaccharide (LPS). Enzyme-linked immunosorbent assay inhibition systems were established by utilizing this antibody, designated 3F11, and 100% inhibition occurred with both LPS and the LPS-LPS and LPS-derived polysaccharides partially inhibited the enzyme-linked immunosorbent assay, whereas similar preparations isolated from Escherichia coli O:111, the J-5 mutant of this strain, and Salmonella minnesota Re595 failed to inhibit the assay. Studies utilizing whole gonococcal strains 4505 and the isogenic variant 4505r, which lacks both the LPS serotype and common determinants as inhibitors, demonstrated that the determinant recognized by the 3F11 antibody was present on the surface of 4505 and absent on 4505r. Inhibition studies were performed with beta-glucose, beta-galactose, D-glucosamine, D-galactosamine, heptose, 2-keto-3-deoxyoctanoate, N-acetylglucosamine, N-acetylgalactosamine, alpha-lactose, and beta-lactose. Complete inhibition of the enzyme-linked immunosorbent assay occurred with D-galactosamine, and partial inhibition was achieved with both alpha-lactose and beta-lactose. Based on these observations, the 3F11 antibody recognizes a site common to gonococcal LPS which is partially shared by meningococcal LPS. The chemical structure of the determinant appears to be a D-galactosamine-O-D-galactopyranosyl-(1-4)-D-glucopyranose. Additional specificity may be conferred by the steric relationship of the determinant on the intact LPS. PMID:6174450

  5. Intestinal Dysbiosis and Lowered Serum Lipopolysaccharide-Binding Protein in Parkinson’s Disease

    PubMed Central

    Hasegawa, Satoru; Goto, Sae; Tsuji, Hirokazu; Okuno, Tatsuya; Asahara, Takashi; Nomoto, Koji; Shibata, Akihide; Fujisawa, Yoshiro; Minato, Tomomi; Okamoto, Akira; Ohno, Kinji; Hirayama, Masaaki

    2015-01-01

    Background The intestine is one of the first affected organs in Parkinson’s disease (PD). PD subjects show abnormal staining for Escherichia coli and ?-synuclein in the colon. Methods We recruited 52 PD patients and 36 healthy cohabitants. We measured serum markers and quantified the numbers of 19 fecal bacterial groups/genera/species by quantitative RT-PCR of 16S or 23S rRNA. Although the six most predominant bacterial groups/genera/species covered on average 71.3% of total intestinal bacteria, our analysis was not comprehensive compared to metagenome analysis or 16S rRNA amplicon sequencing. Results In PD, the number of Lactobacillus was higher, while the sum of analyzed bacteria, Clostridium coccoides group, and Bacteroides fragilis group were lower than controls. Additionally, the sum of putative hydrogen-producing bacteria was lower in PD. A linear regression model to predict disease durations demonstrated that C. coccoides group and Lactobacillus gasseri subgroup had the largest negative and positive coefficients, respectively. As a linear regression model to predict stool frequencies showed that these bacteria were not associated with constipation, changes in these bacteria were unlikely to represent worsening of constipation in the course of progression of PD. In PD, the serum lipopolysaccharide (LPS)-binding protein levels were lower than controls, while the levels of serum diamine oxidase, a marker for intestinal mucosal integrity, remained unchanged in PD. Conclusions The permeability to LPS is likely to be increased without compromising the integrity of intestinal mucosa in PD. The increased intestinal permeability in PD may make the patients susceptible to intestinal dysbiosis. Conversely, intestinal dysbiosis may lead to the increased intestinal permeability. One or both of the two mechanisms may be operational in development and progression of PD. PMID:26539989

  6. The influence of rough lipopolysaccharide structure on molecular interactions with mammalian antimicrobial peptides.

    PubMed

    Bello, Gianluca; Bodin, Alice; Lawrence, M Jayne; Barlow, David; Mason, A James; Barker, Robert D; Harvey, Richard D

    2016-02-01

    The influence of Escherichia coli rough lipopolysaccharide chemotype on the membrane activity of the mammalian antimicrobial peptides (AMPs) human cathelicidin (LL37) and bovine lactoferricin (LFb) was studied on bilayers using solid state (2)H NMR (ssNMR) and on monolayers using the subphase injection technique, Brewster angle microscopy (BAM) and neutron reflectivity (NR). The two AMPs were selected because of their differing biological activities. Chain-deuterated dipalmitoylphosphatidylcholine (d62-DPPC) was added to the LPS samples, to highlight alterations in the system properties caused by the presence of the different LPS chemotypes and upon AMP challenge. Both LPS chemotypes showed a temperature dependent influence on the packing of the DPPC molecules, with a fluidizing effect exerted below the DPPC phase transition temperature (Tm), and an ordering effect observed above the Tm. The magnitude of these effects was influenced by LPS structure; the shorter Rc LPS promoted more ordered lipid packing compared to the longer Ra LPS. These differential ordering effects in turn influenced the penetrative activity of the two peptides, as the perturbation induced by both AMPs to Ra LPS-containing models was greater than that observed in those containing Rc LPS. The NR data suggests that in addition to penetrating into the monolayers, both LL37 and LFb formed a non-interacting layer below the LPS/DPPC monolayer. The overall activity of LL37, which showed a deeper penetration into the model membranes, was more marked than that of LFb, which appeared to localise at the interfacial region, thus providing evidence for the molecular origins of their different biological activities. PMID:26592318

  7. Recognition of Heptoses and the Inner Core of Bacterial Lipopolysaccharides by Surfactant Protein D

    SciTech Connect

    Wang,H.; Head, J.; Kosma, P.; Brade, H.; Muller-Loennies, S.; Sheikh, S.; McDonald, B.; Smith, K.; Cafarella, T.; et al

    2008-01-01

    Lipopolysaccharides (LPS) of Gram-negative bacteria are important mediators of bacterial virulence that can elicit potent endotoxic effects. Surfactant protein D (SP-D) shows specific interactions with LPS, both in vitro and in vivo. These interactions involve binding of the carbohydrate recognition domain (CRD) to LPS oligosaccharides (OS); however, little is known about the mechanisms of LPS recognition. Recombinant neck+CRDs (NCRDs) provide an opportunity to directly correlate binding interactions with a crystallographic analysis of the binding mechanism. In these studies, we examined the interactions of wild-type and mutant trimeric NCRDs with rough LPS (R-LPS). Although rat NCRDs bound more efficiently than human NCRDs to Escherichia coli J-5 LPS, both proteins exhibited efficient binding to solid-phase Rd2-LPS and to Rd2-LPS aggregates presented in the solution phase. Involvement of residues flanking calcium at the sugar binding site was demonstrated by reciprocal exchange of lysine and arginine at position 343 of rat and human CRDs. The lectin activity of hNCRDs was inhibited by specific heptoses, including l-glycero-{alpha}-d-manno-heptose (l, d-heptose), but not by 3-deoxy-{alpha}-d-manno-oct-2-ulosonic acid (Kdo). Crystallographic analysis of the hNCRD demonstrated a novel binding orientation for l, d-heptose, involving the hydroxyl groups of the side chain. Similar binding was observed for a synthetic {alpha}1{yields}3-linked heptose disaccharide corresponding to heptoses I and II of the inner core region in many LPS. 7-O-Carbamoyl-l, d-heptose and d-glycero-{alpha}-d-manno-heptose were bound via ring hydroxyl groups. Interactions with the side chain of inner core heptoses provide a potential mechanism for the recognition of diverse types of LPS by SP-D.

  8. Formation of Crystalline delta-Endotoxin or Poly-beta-Hydroxybutyric Acid Granules by Asporogenous Mutants of Bacillus thuringiensis.

    PubMed

    Wakisaka, Y; Masaki, E; Nishimoto, Y

    1982-06-01

    Parental strains and asporogenous mutants of Bacillus thuringiensis subspp. kurstaki and aizawai produced high yields of delta-endotoxin on M medium, which contained 330 mug of potassium per ml, but not on ST and ST-a media, each of which contained only 11 mug of potassium per ml. On ST and ST-a media, refractile granules were formed instead. These granules had no insecticidal activity against silkworms and were isolated and identified as poly-beta-hydroxybutyric acid. Supplementation of the potassium-deficient ST-a medium with 0.1% KH(2)PO(4) (3.7 mM) led to the formation of crystalline delta-endotoxin. The replacement of KH(2)PO(4) with equimolar amounts of KCl, KNO(3), and potassium acetate or an equivalent amount of K(2)SO(4) had a similar effect, whereas the addition of an equimolar amount of NaH(2)PO(4) or NH(4)H(2)PO(4) did not cause the endotoxin to form. An asporogenous mutant, B. thuringiensis subsp. kurstaki strain 290-1, produced delta-endotoxin on ST-a medium supplemented with 3 mM or more potassium but formed only poly-beta-hydroxybutyric acid granules on the media containing endotoxin by these isolates of B. thuringiensis. Manganese could not be substituted for potassium. Phosphate ions stimulated poly-beta-hydroxybutyric acid formation by strain 290-1. The sporulation of B. thuringiensis and several other Bacillus strains was suppressed on the potassium-deficient ST medium. This suggests that potassium plays an essential role not only in Bacillus cell growth and delta-endotoxin formation but also in sporulation. PMID:16346040

  9. Bacterial colonization and endotoxin content of a new renal dialysis water system composed of acrylonitrile butadiene styrene.

    PubMed Central

    du Moulin, G C; Coleman, E C; Hedley-Whyte, J

    1987-01-01

    We measured endotoxin and bacterial levels in tap water, in water purified by reverse osmosis, and in dialysate samples over a 4-month period in a new 10-bed renal dialysis unit. Water treated by reverse osmosis is conducted to the 10 stations through 111 m of piping composed of acrylonitrile butadiene styrene (ABS). All determinations were made prior to the opening of the unit and after the system was purged for 35 h with all bedside station taps open. Formaldehyde disinfection of the piping system was attempted with a recommended protocol after 11 weeks by feeding 2.5 liters of 37% formaldehyde (0.85%, vol/vol) into the delivery system. Prior to water purging, 24 ng of endotoxin per ml was detected. This level decreased to 2.0 ng of endotoxin after the purging. Levels of endotoxin remained below 1.0 ng of endotoxin per ml throughout the duration of the study. In contrast, the level of viable microorganisms recovered from the treated water was approximately 3.5 X 10(4) CFU/100 ml. Even after disinfection of the system, there was no significant decrease in culturable bacteria from the water even though endotoxin levels were lower. Species isolated from the renal dialysis system were predominately pseudomonads, whereas species isolated from the tap water were Bacillus and Flavobacterium species. ABS provides a surface suitable for long-term colonization and growth of bacteria. Currently recommended decontamination protocols are ineffective in removing potentially pathogenic bacteria from ABS pipes and thus constitute an increased risk to patients undergoing dialysis. Images PMID:3606109

  10. Exposure to Organic Dusts, Endotoxins, and Microorganisms in the Municipal Waste Industry.

    PubMed

    Van Tongeren M; Van Amelsvoort L; Heederik

    1997-01-01

    The waste-collection and -processing industry in Europe is developing rapidly due to environmental constraints in the direction of separate collection, processing, and recycling of waste. It is likely that this will lead to an increase in the number of workers involved in the handling and processing of municipal waste, and an increase in the number of workers exposed to organic dust. This paper reports the results of an occupational hygiene study of the waste-collection and -processing industry (a compost-screening facility, a resource-recovery facility, and two waste-transfer facilities) in The Netherlands. It focuses on organic dusts, endotoxins, and microorganisms (total and gram-negative bacteria and fungi). Levels of exposure to inhalable organic dusts were highest in the waste-processing facilities (compost screening and resource recovery), with average concentrations for organic dusts up to 14.3 mg/m(3) during manual separation of waste and 9.7 mg/m(3) during compost screening activities. Personal endotoxin exposure was highest in the resource-recovery facility, ranging from 32.0 ng/m(3) for the supervisor to 131.1 ng/m(3) during manual separation of waste. High concentrations of microorganisms were found in all facilities. The highest levels for both total fungi and bacteria (<> 10&sup6; cfu/m(3)) were recorded in the dumping pit at the resource-recovery plant and in the dumping pit at one of the waste-transfer plants. It is concluded that high levels of exposures to microorganisms, and to a lesser extent organic dusts and endotoxins, are likely to occur in many processes and activities in the waste-transfer and -processing industry, and that the possibility of health effects due to these exposures cannot be excluded. PMID:9891098

  11. The Impact of a 24-h Ultra-Marathon on Circulatory Endotoxin and Cytokine Profile.

    PubMed

    Gill, S K; Hankey, J; Wright, A; Marczak, S; Hemming, K; Allerton, D M; Ansley-Robson, P; Costa, R J S

    2015-07-01

    The study aimed to determine circulatory endotoxin concentration, cytokine profile, and gastrointestinal symptoms of ultra-endurance runners (UER, n=17) in response to a 24-h continuous ultra-marathon competition (total distance range: 122-208?km) conducted in temperate ambient conditions (0-20 °C) in mountainous terrain. Body mass and body temperature were measured, and venous blood samples were taken before and immediately after competition. Samples were analysed for gram-negative bacterial endotoxin, C-reactive protein, cytokine profile, and plasma osmolality. Gastrointestinal symptoms were also monitored throughout competition. Mean exercise-induced body mass loss was (mean±SD) 1.7±1.8% in UER. Pre- and post-competition plasma osmolality in UER was 286±11?mOsmol·kg(-1) and 286±9?mOsmol·kg(-1), respectively. Pre- to post-competition increases (p<0.05) were observed for endotoxin (37%), C-reactive protein (2832%), IL-6 (3?436%), IL-1? (332%), TNF-? (35%), IL-10 (511%), and IL-8 (239%) concentrations in UER, with no change in the control group (CON; n=12) observed (p>0.05). Gastrointestinal symptoms were reported by 75% of UER, with no symptoms reported by CON. IL-10 (r=0.535) and IL-8 (r=0.503) were positively correlated with gastrointestinal symptoms. A 24-h continuous ultra-marathon competition in temperate ambient conditions resulted in a circulatory endotoxaemia and pro-inflammatory cytokinaemia, counteracted by a compensatory anti-inflammatory response. PMID:25941924

  12. Bovine recombinant lipopolysaccharide binding protein (BRLBP) regulated apoptosis and inflammation response in lipopolysaccharide-challenged bovine mammary epithelial cells (BMEC).

    PubMed

    Sun, Yu; Li, Lian; Wu, Jie; Yu, Pan; Li, Chengmin; Tang, Juan; Li, Xiaojuan; Huang, Shuai; Wang, Genlin

    2015-06-01

    Lipopolysaccharide-binding protein (LBP) is an acute-phase protein involved in host response to Gram-negative and Gram-positive pathogens. It has been reported to exert diverse biological activities, such as anti-inflammatory effects. However, what effects it has on bovine mastitis has not been investigated. The aim of this study was to verify the anti-inflammatory properties of LBP on the inflammatory response of primary bovine mammary epithelial cells (BMEC) induced by lipopolysaccharide (LPS), and to determine the underlying mechanism. Bovine mammary epithelial cells were treated with various concentrations of LPS (1, 10, 20, and 100 ?g/mL) for 3, 6, 12, and 24h. The results showed that LPS significantly inhibited cell viability in a dose-dependent manner. When cells were treated with LPS (10 ?g/mL) for 12 h, the permeability of the cell membrane increased significantly. This promoted apoptosis. Various concentrations (10 and 20 ?g/mL) of bovine recombinant lipopolysaccharide binding protein (BRLBP) could weaken the inflammation injury of BMEC induced by LPS without cytotoxicity. Toll-like receptor 4 (TLR4), nuclear factor ?B (NF-?B), IL-1?, and tumor necrosis factor ? (TNF-?) from BMEC were decreased. TLR4 and NF-?B P65 protein levels were down-regulated, and nuclear transcription factor ?B activity was also weakened. All these results indicated that the protective effects of high concentrations of BRLBP on LPS-induced inflammation injury in BMEC were at least partially achieved by the decreased production of pro-inflammatory cytokines. BRLBP was found to directly inhibit LPS/TLR4-mediated NF-?B activation. One possible anti-inflammatory mechanism can be attributed to the negative role of BRLBP in suppressing TLR4/NF-?B activation mediated by LPS. These findings suggested that BRLBP may be a useful agent to treat LPS-induced mastitis. PMID:25700343

  13. Size-fractionated PM10 monitoring in relation to the contribution of endotoxins in different polluted areas

    NASA Astrophysics Data System (ADS)

    Traversi, D.; Alessandria, L.; Schilirò, T.; Gilli, G.

    2011-07-01

    Particulate pollution is an environmental concern that is widespread and difficult to resolve. Recently various regulatory improvements around the world have been agreed upon to tackle this problem, especially as related to the fine fraction of particulates, which more closely correlates to human health effects than other fractions. The size-fractionation of inhalable particles and their organic composition represent a new area of research that has been poorly explored thus far. Endotoxins are a type of natural organic compound that can be found in particulate matter. They are correlated with Gram-negative bacterial contamination. Health outcomes associated with exposure to these toxins are not specific and often overlap with the health effects of PM (Particulate Matter) exposure, including asthma, bronchitis, acute respiratory distress syndrome and organic dust toxic syndrome. Very little information is available on the endotoxin distribution in different PM10 size fractions. This study examined PM10 size fractions and their endotoxin content. Sampling was conducted at five different locations: one urban, two rural and two rural sites that were highly influenced by large-scale farm animal production facilities. For each location, six different PM10 fractions were evaluated. PM10 sub-fractions were categorised as follows: PM 10-7.2 (1.15-31.30 ?g m -3); PM 7.2-3.0 (1.86-30.73 ?g m -3); PM 3.0-1.5 (1.74-13.90 ?g m -3); PM 1.5-0.95 (0.24-10.57 ?g m -3); PM 0.95-0.49 (1.22-14.33 ?g m -3) and PM <0.49 (13.15-85.49 ?g m -3). The ranges of endotoxin levels determined were: PM 10-7.2 (0.051-5.401 endotoxin units (EU) m -3); PM 7.2-3.0 (0.123-7.801 EU m -3); PM 3.0-1.5 (0.057-1.635 EU m -3); PM 1.5-0.95 (0.040-2.477 EU m -3); PM 0.95-0.49 (0.007-3.159 EU m -3) and PM <0.49 (0.039-3.975 EU m -3). Our results indicated consistency of the PM1 fraction at all of the sites and the predominant presence of endotoxins in the coarse fraction. The observed abatement of the PM10 and endotoxin levels was very high (above 1:10) as little as 50 m from the pollution source. This kind of model is useful to both improve our knowledge about PM10 endotoxin distribution and to evaluate the potential risks for the health of neighbouring populations.

  14. [Sensitivity of dissociation variants of Micrococcus luteus to the action of delta-endotoxins of Bacillus thuringiensis].

    PubMed

    Iudina, T G; Mil'ko, E S; Egorov, N S

    1996-01-01

    Endotoxins of Bacillus thuringiensis subsp. tenebrionis produced an antibiotic effect on three out of the four species of micrococci tested, showing an activity of 10-23 units/mg, comparable with that of bacitracin. The R variants of Micrococcus luteus were more than twice as resistant to the action of delta-endotoxins as cells of the S and M types. Enhanced growth of the tested microorganisms at concentrations of antibiotics large enough to inhibit the growth of the S and M variants, but insufficient to suppress the R-variant, was shown to be determined by the intense development of the latter variant. PMID:8992244

  15. Monitoring the effectiveness of root canal procedures on endotoxin levels found in teeth with chronic apical periodontitis

    PubMed Central

    MARINHO, Ariane Cassia Salustiano; MARTINHO, Frederico Canato; ZAIA, Alexandre Augusto; FERRAZ, Caio Cezar Randi; GOMES, Brenda Paula Figueiredo de Almeida

    2014-01-01

    Objective: The aim of this study was to monitor the effectiveness of root canal procedures by using different irrigants and intracanal medication on endotoxin levels found in root canals of teeth with chronic apical periodontitis. Material and Methods: Thirty root canals of teeth with pulpal necrosis associated with periapical lesions were selected and randomly divided into groups according to the irrigants used: GI - 2.5% NaOCl, GII - 2% chlorhexidine (CHX) gel, and GIII - saline solution (SS) (all, n=10). Samples were collected with sterile/apyrogenic paper points before (S1) and after root canal instrumentation (S2), after use of 17% ethylenediaminetetraacetic acid (EDTA) (S3), and after 30 days of intracanal medication (Ca(OH)2+SS) (S4). A turbidimetric kinetic Limulus Amebocyte Lysate assay was used for endotoxin measurement. Results: Endotoxins were detected in 100% of the root canals investigated (30/30), with a median value of 18.70 EU/mL. After S2, significant median percentage reduction was observed in all groups, irrespective of the irrigant tested: 2.5% NaOCl (99.65%) (GI), 2% CHX (94.27%) (GII), and SS (96.79%) (GIII) (all p<0.05). Root canal rinse with 17% EDTA (S3) for a 3-minute period failed to decrease endotoxin levels in GI and a slight decrease was observed in GII (59%) and GIII (61.1%) (all p>0.05). Intracanal medication for 30 days was able to significantly reduce residual endotoxins: 2.5% NaOCl (90%) (GI), 2% CHX (88.8%) (GII), and SS (85.7%) (GIII, p<0.05). No differences were found in the endotoxin reduction when comparing s2 and s4 treatment groups. Conclusion: Our findings demonstrated the effectiveness of the mechanical action of the instruments along with the flow and backflow of irrigant enduring root canal instrumentation for the endotoxin removal from root canals of teeth with chronic apical periodontitis. Moreover, the use of intracanal medication for 30 days contributed for an improvement of endotoxin reduction. PMID:25075670

  16. A Mannosyl Transferase Required for Lipopolysaccharide Inner Core Assembly in Rhizobium leguminosarum

    PubMed Central

    Kanipes, Margaret I.; Ribeiro, Anthony A.; Lin, Shanhua; Cotter, Robert J.; Raetz, Christian R. H.

    2008-01-01

    The lipopolysaccharide (LPS) core domain of Gram-negative bacteria plays an important role in outer membrane stability and host interactions. Little is known about the biochemical properties of the glycosyltransferases that assemble the LPS core. We now report the purification and characterization of the Rhizobium leguminosarum mannosyl transferase LpcC, which adds a mannose unit to the inner 3-deoxy-D-manno-octulosonic acid (Kdo) moiety of the LPS precursor, Kdo2-lipid IVA. LpcC containing an N-terminal His6 tag was assayed using GDP-mannose as the donor and Kdo2-[4?-32P]lipid IVA as the acceptor and was purified to near homogeneity. Sequencing of the N terminus confirmed that the purified enzyme is the lpcC gene product. Mild acid hydrolysis of the glycolipid generated in vitro by pure LpcC showed that the mannosylation occurs on the inner Kdo residue of Kdo2-[4?-32P]lipid IVA. A lipid acceptor substrate containing two Kdo moieties is required by LpcC, since no activity is seen with lipid IVA or Kdo-lipid IVA. The purified enzyme can use GDP-mannose or, to a lesser extent, ADP-mannose (both of which have the ?-anomeric configuration) for the glycosylation of Kdo2-[4?-32P]lipid IVA. Little or no activity is seen with ADP-glucose, UDP-glucose, UDP-GlcNAc, or UDP-galactose. A Salmonella typhimurium waaC mutant, which lacks the enzyme for incorporating the inner L-glycero-D-manno-heptose moiety of LPS, regains LPS with O-antigen when complemented with lpcC. An Escherichia coli heptose-less waaC-waaF deletion mutant expressing the R. leguminosarum lpcC gene likewise generates a hybrid LPS species consisting of Kdo2-lipid A plus a single mannose residue. Our results demonstrate that heterologous lpcC expression can be used to modify the structure of the Salmonella and E. coli LPS cores in living cells. PMID:12591937

  17. Exposure to airborne Gram-negative bacteria, dust and endotoxin in paper factories.

    PubMed

    Prazmo, Zofia; Dutkiewicz, Jacek; Skórska, Czes?awa; Sitkowska, Jolanta; Cholewa, Grazyna

    2003-01-01

    Air samples for determination of the concentration of Gram-negative bacteria, dust and endotoxin were collected at 10 sites in 2 large pulp and paper mills (paper factories) located in northern Poland, of which one (plant "A") was an older type facility while the other (plant "B") was a modern, fully automated factory with an effective ventilatory system. In both factories paper was produced from wood chips derived mostly from Scots pine. The concentrations of Gram-negative bacteria in the air of examined factories were within a range of 11.0-310.0 cfu/m(3), being greatest in the old type factory "A" at the initial stages of production cycle comprising handling of chips and pulp production. The mean value for these sites (246.9 cfu/m(3)) was significantly greater (t-test, p < 0.01) compared to final stages of paper production in the same factory (mean 32.1 cfu/m(3)) and to corresponding stages of chip handling in the modern "B" factory (mean 94.4 cfu/m(3)). The values of the respirable fraction of airborne Gram-negative flora were at most sites within a range of 40.0-56.9%. The species of the family Enterobacteriaceacae, mostly belonging to the genera Enterobacter, Pantoea, Rahnella and Klebsiella, distinctly prevailed in the air of the examined factories. Altogether, 19 species or genera of Gram-negative bacteria were identified in the collected air samples, out of these 9 were reported as having allergenic, immunotoxic and/or infectious properties. The concentration of dust in the air of paper factories ranged from 0.13-3.9 mg/m(3) and never exceeded the safe level. The concentration of bacterial endotoxin in the air of paper factories varied within a fairly wide range of 0.0042-2.5 micro g/m(3). At 4 sites associated with initial chip handling and pulp production large concentrations of airborne endotoxin between 0.2-2.5 micro g/m(3) were found, significantly exceeding suggested safe levels. In conclusion, despite Gram-negative bacteria occur in the air of paper mills in relatively low concentrations which never exceeded the value of 1,000 cfu/m(3) proposed as safe level, they may exert adverse effects on exposed workers, as evidenced by high concentrations of airborne endotoxin and the presence of numerous potentially pathogenic species. Thus, these microorganisms pose a potential risk of respiratory disease for the workers of pulp and paper mills, in particular for those engaged in handling of wood chips and production of pulp. PMID:12852739

  18. Effects of ozone and endotoxin coexposure on rat airway epithelium: potentiation of toxicant-induced alterations.

    PubMed Central

    Wagner, J G; Hotchkiss, J A; Harkema, J R

    2001-01-01

    Tropospheric ozone is the major oxidizing component in photochemical smog and is one of the most pervasive problems to human health of the criteria air pollutants for which the National Ambient Air Quality Standards have been designated by the Clean Air Act. Although many adverse health effects of ozone exposure have been documented in both humans and laboratory animals, controversy surrounds the establishment and implementation of ozone standards set forth by the U.S. Environmental Protection Agency. Because people are commonly exposed to more than one air pollutant at a time, studies that examine coexposures to airborne materials may be more relevant for assessing their risks to human health. Airborne biogenic substances such as pollens, spores, and bacterial products are ubiquitous in the environment, and when inhaled can cause adverse respiratory symptoms. One such biogenic agent, bacterial endotoxin, is a potent stimulus of airway inflammation and is a ubiquitous airborne contaminant commonly found in domestic, agricultural, and industrial settings. Little is known about the interaction of exposures to biogenic substances and criteria air pollutants such as ozone. In the last few years we have performed a series of studies in rodents that examined the biologic responses of the respiratory epithelium after airway exposures to both endotoxin and ozone. When exposed to ozone (0.5 ppm 8 hr/day for 3 days), Fischer rats develop lesions in the nasal transitional epithelium, whereas intranasal instillation of endotoxin (20 microg) elicits epithelial lesions in the respiratory epithelium of the nose and conducting airways. Our studies were designed to examine how exposure to one toxicant may affect the airway epithelial lesions induced by the other toxicant. We investigated the potential role of acute inflammation in the enhancement of airway epithelial lesions after exposure of these two toxicants in neutrophil-sufficient and neutrophil-deficient rodents. A summary of these results indicates that epithelial and inflammatory responses to coexposure of these two pollutants are greater than those elicited by either agent alone. Interestingly, each toxicant enhances the epithelial alterations induced by the other. Furthermore, the synergistic effects elicited by coexposure to ozone and endotoxin are mediated partly by neutrophils. These studies provided some new insights into how inhaled co-pollutants interact to initiate and promote alterations of airway epithelium. Further studies with these and other air pollutants will help define their true risk to human health. PMID:11544169

  19. Pathophysiology of endotoxin: microvascular dysfunction, and the roles of VEGF and nitric oxide (NO) 

    E-print Network

    Naftanel, Mark Andrew

    2013-02-22

    tultillment of thc requirements of the Lqx'IYERSITY LNDFRGRADLiATE RESFARCH FELLOWS Api il 200 l Group Biomedical Sciences PATHOPHYSIOLOGW OF ENDOTOXIN: IYI I CROYA SCU I. A R D YS F LI N CT I ON, A!VD THE ROLES OF YEGF AND NITRIC OXIDE (VO) A Senior... to VFGF have not been examined tJI'c compared microvascular endothelium-dependent relaxation (EDR) to VFGF' ' (10 '"- 3x10rnM) in mesenteric microvessels (--150 pm) isolated from comrol (sterile saline-treated) and endotoxemic (J. , cr&A LPS, 0 m~~'kg i...

  20. Effects of duration of moderate increases in grain feeding on endotoxins in the digestive tract and acute phase proteins in peripheral blood of yearling calves.

    PubMed

    Plaizier, J C; Li, S; Le Sciellour, M; Schurmann, B L; Górka, P; Penner, G B

    2014-11-01

    Effects of duration of grain feeding on the concentration of endotoxic lipopolysaccharide (LPS) in digesta throughout the digestive tract and on acute phase proteins and LPS in peripheral blood were determined in Holstein yearling calves. Twenty-five Holstein yearling steer calves received either a forage-based diet containing 92% hay and 8% of a mineral and vitamin pellet on a dry matter basis (CON) or a moderate-grain diet, obtained by replacing 41.5% of the hay in the forage-based diet with barley grain, for 3 (MG3), 7 (MG7), 14 (MG14), or 21 d (MG21) before slaughter. Immediately before slaughter, blood samples were collected from the jugular vein. Immediately after slaughter, digesta samples were collected from the rumen, jejunum, ileum, cecum, colon, and rectum. Rumen liquid digesta, digesta from the intestines, and peripheral blood plasma were analyzed for LPS. Peripheral blood plasma and serum were analyzed for the acute phase proteins amyloid A, haptoglobin, and LPS-binding protein. Feeding the grain diet increased the LPS concentration in rumen fluid linearly from 15,488 endotoxin units (EU)/mL for CON to 70,146 EU/mL for MG7. Concentrations of LPS in rumen fluid in MG14 and MG21 were 61,944 and 56,234 EU/mL, respectively, and did not differ. The LPS concentrations in jejunal digesta were much lower than that in digesta elsewhere in the digestive tract, which suggests that ruminal LPS is broken down in the abomasum or proximal jejunum. The concentration of digesta LPS in the ileum was higher than that of digesta elsewhere in the intestines and similar to that in rumen fluid. The duration of grain feeding increased the LPS concentration in digesta in the ileum and cecum and tended to increase that in the colon cubically. Concentrations of LPS in this part of the digestive tract were highest in the MG3 and MG21 groups. The highest concentrations of LPS in digesta in the cecum, colon, and rectum were 3.7, 3.8, and 5.6 times higher than that in CON, respectively. Grain feeding and the increase in LPS in digesta were not accompanied by an acute phase response or a detectable concentration of LPS in peripheral blood. The absence of LPS in peripheral blood and the lack of increase in acute phase proteins indicated that the grain feeding protocol used in the current study and the accompanying changes in LPS concentrations of the digesta did not result in systemic inflammation. PMID:25242427

  1. L-Ascorbate Attenuates the Endotoxin-Induced Production of Inflammatory Mediators by Inhibiting MAPK Activation and NF-?B Translocation in Cortical Neurons/Glia Cocultures

    PubMed Central

    Huang, Ya-Ni; Lai, Chien-Cheng; Chiu, Chien-Tsai; Lin, Jhen-Jhe; Wang, Jia-Yi

    2014-01-01

    In response to acute insults to the central nervous system, such as pathogen invasion or neuronal injuries, glial cells become activated and secrete inflammatory mediators such as nitric oxide (NO), cytokines, and chemokines. This neuroinflammation plays a crucial role in the pathophysiology of chronic neurodegenerative diseases. Endogenous ascorbate levels are significantly decreased among patients with septic encephalopathy. Using the bacterial endotoxin lipopolysaccharide (LPS) to induce neuroinflammation in primary neuron/glia cocultures, we investigated how L-ascorbate (vitamin C; Vit. C) affected neuroinflammation. LPS (100 ng/ml) induced the expression of inducible NO synthase (iNOS) and the production of NO, interleukin (IL)-6, and macrophage inflammatory protein-2 (MIP-2/CXCL2) in a time-dependent manner; however, cotreatment with Vit. C (5 or 10 mM) attenuated the LPS-induced iNOS expression and production of NO, IL-6, and MIP-2 production. The morphological features revealed after immunocytochemical staining confirmed that Vit. C suppressed LPS-induced astrocytic and microglial activation. Because Vit. C can be transported into neurons and glia via the sodium-dependent Vit. C transporter-2, we examined how Vit. C affected LPS-activated intracellular signaling in neuron/glia cocultures. The results indicated the increased activation (caused by phosphorylation) of mitogen-activated protein kinases (MAPKs), such as p38 at 30 min and extracellular signal-regulated kinases (ERKs) at 180 min after LPS treatment. The inhibition of p38 and ERK MAPK suppressed the LPS-induced production of inflammatory mediators. Vit. C also inhibited the LPS-induced activation of p38 and ERK. Combined treatments of Vit. C and the inhibitors of p38 and ERK yielded no additional inhibition compared with using the inhibitors alone, suggesting that Vit. C functions through the same signaling pathway (i.e., MAPK) as these inhibitors. Vit. C also reduced LPS-induced I?B-? degradation and NF-?B translocation. Thus, Vit. C suppressed the LPS-stimulated production of inflammatory mediators in neuron/glia cocultures by inhibiting the MAPK and NF-?B signaling pathways. PMID:24983461

  2. Endotoxin activates human vascular smooth muscle cells despite lack of expression of CD14 mRNA or endogenous membrane CD14.

    PubMed Central

    Loppnow, H; Stelter, F; Schönbeck, U; Schlüter, C; Ernst, M; Schütt, C; Flad, H D

    1995-01-01

    During infection or inflammation, cells of the blood vessel wall, such as endothelial cells (EC) and smooth muscle cells (SMC), contribute to the regulation of the immune response by production of cytokines or expression of adhesion molecules. Little is known about the mechanism(s) involved in the stimulation of vascular cells by endotoxin (lipopolysaccharide [LPS]). As reported previously, LPS antagonists reduce LPS-induced cytokine production or adhesion in vitro specifically, suggesting a specific LPS recognition mechanism. We thus investigated the role of CD14 for stimulation of vascular SMC by LPS. Complement-fixing antibodies directed against CD14 (LeuM3, RoMo I, or Mo2) lysed monocytes but failed to mediate lysis of EC or SMC, indicating the lack of endogenous membrane CD14 in vascular cells. In addition, we did not detect expression of CD14 protein on EC and SMC in cell sorting analysis or cell immunoassay experiments. These observations are in line with our finding that a CD14 probe did not hybridize with mRNA or EC or SMC in Northern (RNA) blot experiments, although it hybridized well with monocyte-derived mRNA. We obtained the same results with the much more sensitive reverse transcription-PCR. Since the vascular SMC did not express endogenous CD14, we investigated the role of human serum-derived soluble CD14 (sCD14) for activation of SMC by LPS. In medium containing human serum, anti-CD14 antibodies inhibited activation of SMC by LPS. In contrast, the same antibodies did not inhibit activation of cells cultured in medium containing fetal calf serum. SMC cultured in sCD14-depleted medium responded 1,000-fold less to LPS than cells cultured in presence of sCD14. Reconstitution of sCD14-depleted serum or supplementation of serum-free medium with recombinant CD14 restored the capacity of the cells to respond to LPS. These results show that specific activation of vascular SMC by LPS does not involve binding to endogenous membrane CD14, but that the activation of vascular SMC by LPS is mediated to a great extent by serum-derived sCD14. PMID:7532623

  3. Visualization of bacteriophage P1 infection by cryo-electron tomography of tiny Escherichia coli

    SciTech Connect

    Liu Jun; Chen Chengyen; Shiomi, Daisuke; Niki, Hironori; Margolin, William

    2011-09-01

    Bacteriophage P1 has a contractile tail that targets the conserved lipopolysaccharide on the outer membrane surface of the host for initial adsorption. The mechanism by which P1 DNA enters the host cell is not well understood, mainly because the transient molecular interactions between bacteriophage and bacteria have been difficult to study by conventional approaches. Here, we engineered tiny E. coli host cells so that the initial stages of P1-host interactions could be captured in unprecedented detail by cryo-electron tomography. Analysis of three-dimensional reconstructions of frozen-hydrated specimens revealed three predominant configurations: an extended tail stage with DNA present in the phage head, a contracted tail stage with DNA, and a contracted tail stage without DNA. Comparative analysis of various conformations indicated that there is uniform penetration of the inner tail tube into the E. coli periplasm and a significant movement of the baseplate away from the outer membrane during tail contraction.

  4. Genome-Wide Assessment of Outer Membrane Vesicle Production in Escherichia coli

    PubMed Central

    Kulp, Adam J.; Sun, Bo; Ai, Teresa; Manning, Andrew J.; Orench-Rivera, Nichole

    2015-01-01

    The production of outer membrane vesicles by Gram-negative bacteria has been well documented; however, the mechanism behind the biogenesis of these vesicles remains unclear. Here a high-throughput experimental method and systems-scale analysis was conducted to determine vesiculation values for the whole genome knockout library of Escherichia coli mutant strains (Keio collection). The resultant dataset quantitatively recapitulates previously observed phenotypes and implicates nearly 150 new genes in the process of vesiculation. Gene functional and biochemical pathway analyses suggest that mutations that truncate outer membrane structures such as lipopolysaccharide and enterobacterial common antigen lead to hypervesiculation, whereas mutants in oxidative stress response pathways result in lower levels. This study expands and refines the current knowledge regarding the cellular pathways required for outer membrane vesiculation in E. coli. PMID:26406465

  5. Structure of the core oligosaccharide in the serotype O8 lipopolysaccharide from Klebsiella pneumoniae.

    PubMed Central

    Severn, W B; Kelly, R F; Richards, J C; Whitfield, C

    1996-01-01

    Two classes of mutants with O-antigen-deficient lipopolysaccharides were isolated from the serotype O8 reference strain, belonging to Klebsiella pneumoniae subspecies ozaenae. These mutants were selected by resistance to bacteriophage KO1-2, which recognizes and lyses strains with lipopolysaccharide molecules containing the D-galactan II O antigen. Strain RFK-11 contains a defect in O-antigen synthesis and has a complete core, including the attachment site for O antigen. This mutation is complemented by a plasmid carrying the rfb (O-antigen biosynthesis) gene cluster from the related K. pneumoniae serotype O1. In sodium dodecyl sulfate-polyacrylamide gel electrophoresis, the lipopolysaccharide from strain RFK-9 has a mobility typical of deep-rough lipopolysaccharide. RFK-9 lipopolysaccharide lacks the attachment site for O antigen. Lipopolysaccharides from strains RFK-9 and RFK-11 were isolated, and their structures were determined by methylation analyses, muclear magnetic resonance spectroscopy, and mass spectroscopy. The deduced O8 core oligosaccharide includes the partial core structure reported for the K. pneumoniae subspecies pneumoniae serotype O1 lipopolysaccharide (M. Süsskind, S. Müller-Leonnies, W. Nimmich, H. Brade, and O. Holst, Carbohydr. Res. 269:C1-7, 1995), consistent with the possibility of a conserved core structure within the species. The core oligosaccharide differs from those of the genera Salmonella and Escherichia by the absence of a hexose-containing outer core, the lack of phosphate residues in the inner core, and the presence of galacturonic acid residues. PMID:8626303

  6. Facile biofunctionalization of silver nanoparticles for enhanced antibacterial properties, endotoxin removal, and biofilm control

    PubMed Central

    Lambadi, Paramesh Ramulu; Sharma, Tarun Kumar; Kumar, Piyush; Vasnani, Priyanka; Thalluri, Sitaramanjaneya Mouli; Bisht, Neha; Pathania, Ranjana; Navani, Naveen Kumar

    2015-01-01

    Infectious diseases cause a huge burden on healthcare systems worldwide. Pathogenic bacteria establish infection by developing antibiotic resistance and modulating the host’s immune system, whereas opportunistic pathogens like Pseudomonas aeruginosa adapt to adverse conditions owing to their ability to form biofilms. In the present study, silver nanoparticles were biofunctionalized with polymyxin B, an antibacterial peptide using a facile method. The biofunctionalized nanoparticles (polymyxin B-capped silver nanoparticles, PBSNPs) were assessed for antibacterial activity against multiple drug-resistant clinical strain Vibrio fluvialis and nosocomial pathogen P. aeruginosa. The results of antibacterial assay revealed that PBSNPs had an approximately 3-fold higher effect than the citrate-capped nanoparticles (CSNPs). Morphological damage to the cell membrane was followed by scanning electron microscopy, testifying PBSNPs to be more potent in controlling the bacterial growth as compared with CSNPs. The bactericidal effect of PBSNPs was further confirmed by Live/Dead staining assays. Apart from the antibacterial activity, the biofunctionalized nanoparticles were found to resist biofilm formation. Electroplating of PBSNPs onto stainless steel surgical blades retained the antibacterial activity against P. aeruginosa. Further, the affinity of polymyxin for endotoxin was exploited for its removal using PBSNPs. It was found that the prepared nanoparticles removed 97% of the endotoxin from the solution. Such multifarious uses of metal nanoparticles are an attractive means of enhancing the potency of antimicrobial agents to control infections. PMID:25834431

  7. Facile biofunctionalization of silver nanoparticles for enhanced antibacterial properties, endotoxin removal, and biofilm control.

    PubMed

    Lambadi, Paramesh Ramulu; Sharma, Tarun Kumar; Kumar, Piyush; Vasnani, Priyanka; Thalluri, Sitaramanjaneya Mouli; Bisht, Neha; Pathania, Ranjana; Navani, Naveen Kumar

    2015-01-01

    Infectious diseases cause a huge burden on healthcare systems worldwide. Pathogenic bacteria establish infection by developing antibiotic resistance and modulating the host's immune system, whereas opportunistic pathogens like Pseudomonas aeruginosa adapt to adverse conditions owing to their ability to form biofilms. In the present study, silver nanoparticles were biofunctionalized with polymyxin B, an antibacterial peptide using a facile method. The biofunctionalized nanoparticles (polymyxin B-capped silver nanoparticles, PBSNPs) were assessed for antibacterial activity against multiple drug-resistant clinical strain Vibrio fluvialis and nosocomial pathogen P. aeruginosa. The results of antibacterial assay revealed that PBSNPs had an approximately 3-fold higher effect than the citrate-capped nanoparticles (CSNPs). Morphological damage to the cell membrane was followed by scanning electron microscopy, testifying PBSNPs to be more potent in controlling the bacterial growth as compared with CSNPs. The bactericidal effect of PBSNPs was further confirmed by Live/Dead staining assays. Apart from the antibacterial activity, the biofunctionalized nanoparticles were found to resist biofilm formation. Electroplating of PBSNPs onto stainless steel surgical blades retained the antibacterial activity against P. aeruginosa. Further, the affinity of polymyxin for endotoxin was exploited for its removal using PBSNPs. It was found that the prepared nanoparticles removed 97% of the endotoxin from the solution. Such multifarious uses of metal nanoparticles are an attractive means of enhancing the potency of antimicrobial agents to control infections. PMID:25834431

  8. Coordinated Regulation of miR-155 and miR-146a Genes during Induction of Endotoxin Tolerance in Macrophages.

    PubMed

    Doxaki, Christina; Kampranis, Sotirios C; Eliopoulos, Aristides G; Spilianakis, Charalampos; Tsatsanis, Christos

    2015-12-15

    Endotoxin tolerance occurs to protect the organism from hyperactivation of innate immune responses, primarily mediated by macrophages. Regulation of endotoxin tolerance occurs at multiple levels of cell responses and requires significant changes in gene expression. In the process of macrophage activation, induced expression of microRNA (miR)-155 and miR-146a contributes to the regulation of the inflammatory response and endotoxin tolerance. In this article, we demonstrate that expression of both miRNAs is coordinately regulated during endotoxin tolerance by a complex mechanism that involves monoallelic interchromosomal association, alterations in histone methyl marks, and transcription factor binding. Upon activation of naive macrophages, Histone3 was trimethylated at lysine4 and NF?Bp65 was bound on both miR-155 and miR-146a gene loci. However, at the stage of endotoxin tolerance, both miR gene loci were occupied by C/EBP?, NF?Bp50, and the repressive Histone3 marks trimethylation of K9 of H3. DNA fluorescence in situ hybridization experiments revealed monoallelic interchromosomal colocalization of miR-155 and miR-146a gene loci at the stage of endotoxin tolerance, whereas RNA-DNA-fluorescence in situ hybridization experiments showed that the colocalized alleles were silenced, suggesting a common repression mechanism. Genetic ablation of Akt1, which is known to abrogate endotoxin tolerance, abolished induction of loci colocalization and C/EBP? binding, further supporting that this mechanism occurs specifically in endotoxin tolerance. Overall, this study demonstrates that two miRNAs are coordinately regulated via gene colocalization at the three-dimensional chromatin space, same transcriptional machinery, and similar Histone3 methylation profile, contributing to the development of endotoxin tolerance. PMID:26538391

  9. Viscoelastic and ultrastructural characteristics of whole blood and plasma in Alzheimer-type dementia, and the possible role of bacterial lipopolysaccharides (LPS).