Glucose utilization and role of blood in endotoxin shock.

1977 ◽  
Vol 233 (2) ◽  
pp. E71
Author(s):  
L B Hinshaw ◽  
L T Archer ◽  
B K Beller ◽  
G L White ◽  
T M Schroeder ◽  
...  
Keyword(s):  
Glucose Uptake ◽  
Glucose Utilization ◽  
Lactic Acid Production ◽  
White Blood Cells ◽  
Endotoxin Shock ◽  
E Coli ◽  
Predicted Values

The present study was conducted to explore influences modifying glucose uptake in canine blood administered LD100 E. coli endotoxin. Particular emphasis was given to assay the role of the white blood cell (WBC) in glucose utilization. Significant increases in glucose uptake and lactic acid production, attributed to increased activity of the WBC, were observed 1-3 h after endotoxin was added to blood in vitro. Although a net increase in glucose utilization was noted, endotoxin simultaneously exerted adverse effects by depressing glucose uptake below predicted values (Q10 = 2.12 with LD100 endotoxin vs. 2.78 in saline controls) and increasing WBC mortality rate. Blood from dogs pretreated with sublethal doses of endotoxin in vivo utilized glucose at an accelerated rate when subjected to endotoxin in vitro. Excess glucose was consumed because of elevated numbers of white blood cells although additional glucose requirements after endotoxin were independent of temperature between the ranges of 34-41 degrees C. All animals pretreated with daily sublethal injections of endotoxin for 3 days survived superlethal doses of endotoxin.

scholarly journals Arabidopsis Disulfide Reductase, Trx-h2, Functions as an RNA Chaperone under Cold Stress

2021 ◽  
Vol 11 (15) ◽  
pp. 6865
Author(s):  
Eun Seon Lee ◽  
Joung Hun Park ◽  
Seong Dong Wi ◽  
Ho Byoung Chae ◽  
Seol Ki Paeng ◽  
...  
Keyword(s):  
Cold Stress ◽  
Wild Type ◽  
Rna Chaperone ◽  
E Coli ◽  
Cold Sensitive ◽  
Thioredoxin H ◽  
Functional Rnas

The thioredoxin-h (Trx-h) family of Arabidopsis thaliana comprises cytosolic disulfide reductases. However, the physiological function of Trx-h2, which contains an additional 19 amino acids at its N-terminus, remains unclear. In this study, we investigated the molecular function of Trx-h2 both in vitro and in vivo and found that Arabidopsis Trx-h2 overexpression (Trx-h2OE) lines showed significantly longer roots than wild-type plants under cold stress. Therefore, we further investigated the role of Trx-h2 under cold stress. Our results revealed that Trx-h2 functions as an RNA chaperone by melting misfolded and non-functional RNAs, and by facilitating their correct folding into active forms with native conformation. We showed that Trx-h2 binds to and efficiently melts nucleic acids (ssDNA, dsDNA, and RNA), and facilitates the export of mRNAs from the nucleus to the cytoplasm under cold stress. Moreover, overexpression of Trx-h2 increased the survival rate of the cold-sensitive E. coli BX04 cells under low temperature. Thus, our data show that Trx-h2 performs function as an RNA chaperone under cold stress, thus increasing plant cold tolerance.

Abstract 344: FNDC5, a PGC1-a-Dependent Myokine, Increases Glucose Utilization and Fatty-Acid Oxidation by AMPK Signaling Pathway

2013 ◽  
Vol 113 (suppl_1) ◽  
Author(s):  
Ling Tao ◽  
Yi Liu ◽  
Chao Xin ◽  
Weidong Huang ◽  
Lijian Zhang ◽  
...  
Keyword(s):  
Fatty Acid ◽  
Glucose Uptake ◽  
Fatty Acid Oxidation ◽  
Glucose Utilization ◽  
C2c12 Cells ◽  
Time Dependent ◽  
Acid Oxidation ◽  
Ampk Signaling

FNDC5 is a hormone secreted by myocytes that could reduce obesity and insulin resistance, However, the exact effect of FNDC5 on glucose and lipid metabolism remain poorly identified; More importantly, the signaling pathways that mediate the metabolic effects of FNDC5 is completely unknown. Here we showed that FNDC5 stimulates β-oxidation and glucose uptake in C2C12 cells in a dose- and time-dependent fashion in vitro (n=8, all P<0.01). In vivo study revealed that FNDC5 also enhanced glucose tolerance in diabetic mice and increased the glucose uptake evidenced by increased [18F] FDG accumulation in hearts by PET scan (n=6, all P<0.05). FNDC5 decreased the expression of gluconeogenesis related molecules (PEPCK and G6Pase) and increased the phosphorylation of ACC, a key modulator of fatty-acid oxidation, both in hepatocytes and C2C12 cells (n=3, all P<0.05). In parallel with its stimulation of β-oxidation and glucose uptake, FNDC5 increased the phosphorylation of AMPK both in hepatocytes and C2C12 cells in a dose- and time-dependent fashion in vitro and in vivo. More importantly, the β-oxidation and glucose uptake, the expression of PEPCK and G6Pase and the phosphorylation of ACC induced by FNDC5 were attenuated by AMPK inhibitor in hepatocytes and C2C12 cells (P<0.05). Most importantly, the FNDC5 induced glucose uptake and phosphorylation of ACC were attenuated in AMPK-DN mice (n=6, all P<0.05). The glucose-lowering effect of FNDC5 in diabetic mice was also attenuated by AMPK inhibitor. Our data presents the direct evidence that FNDC5 stimulates glucose utilization and fatty-acid oxidation by AMPK signaling pathway, suggesting that FNDC5 be a novel pharmacological approach for type 2 diabetes.

scholarly journals Regulatory Role of PlaR (YiaJ) for Plant Utilization in Escherichia coli K-12

2019 ◽  
Vol 9 (1) ◽  
Author(s):  
Tomohiro Shimada ◽  
Yui Yokoyama ◽  
Takumi Anzai ◽  
Kaneyoshi Yamamoto ◽  
Akira Ishihama
Keyword(s):  
Escherichia Coli ◽  
Genetic System ◽  
Regulatory Role ◽  
E Coli ◽  
Warm Blooded Animal ◽  
Plant Utilization ◽  
K 12

AbstractOutside a warm-blooded animal host, the enterobacterium Escherichia coli K-12 is also able to grow and survive in stressful nature. The major organic substance in nature is plant, but the genetic system of E. coli how to utilize plant-derived materials as nutrients is poorly understood. Here we describe the set of regulatory targets for uncharacterized IclR-family transcription factor YiaJ on the E. coli genome, using gSELEX screening system. Among a total of 18 high-affinity binding targets of YiaJ, the major regulatory target was identified to be the yiaLMNOPQRS operon for utilization of ascorbate from fruits and galacturonate from plant pectin. The targets of YiaJ also include the genes involved in the utilization for other plant-derived materials as nutrients such as fructose, sorbitol, glycerol and fructoselysine. Detailed in vitro and in vivo analyses suggest that L-ascorbate and α-D-galacturonate are the effector ligands for regulation of YiaJ function. These findings altogether indicate that YiaJ plays a major regulatory role in expression of a set of the genes for the utilization of plant-derived materials as nutrients for survival. PlaR was also suggested to play protecting roles of E. coli under stressful environments in nature, including the formation of biofilm. We then propose renaming YiaJ to PlaR (regulator of plant utilization).

scholarly journals Role of interleukin-1 and tumour necrosis factor in leukocyte recruitment to acute dermal inflammation

1992 ◽  
Vol 1 (5) ◽  
pp. 347-353 ◽  
Author(s):  
Andrew C. Issekutz ◽  
Nancy Lopes ◽  
Thomas B. Issekutz
Keyword(s):  
Monoclonal Antibody ◽  
Umbilical Vein ◽  
Interleukin 1 ◽  
E Coli ◽  
Tnf Α ◽  
Lps Activation ◽  
Necrosis Factor

The cytokines IL-1 and TNF-α are involved in inflammation and their production is stimulated by various agents, especially endotoxin (LPS). Here, using the human IL-1 receptor antagonist (IL-1RA) and a new monoclonal antibody (mAb 7F11) to rabbit TNF, the role of endogenous IL-l and TNF production in acute (3h) leukocyte (PMNL) recruitment to dermal inflammation in rabbits has been studied. IL-1RA inhibited by 27% the PMNL accumulation in reactions induced by killed Escherichia coli (p < 0.05) but not by LPS. The monoclonal antibody to TNF inhibited by 27% and 38% (p < 0.002) the PMNL accumulation in LPS and E. coli reactions respectively, but a combination of the mAb with IL-1RA was not more effective. Treatment of human umbilical vein endothelium with LPS for 3 h activated endothelium to induce PMNL transendothelial migration in vitro, which was not inhibited by IL-1RA, antibody to TNF-α, IL-1 or to IL-8. In conclusion, TNF and IL-1 may partially mediate acute PMNL infiltration in vivo to LPS and Gram negative bacteria, but there is a major IL-1/TNF independent mechanism, at least in dermal inflammation, which may be due to direct LPS activation of the microvasculature or perhaps the generation of cytokines other than IL-1 and TNF.

scholarly journals Role of Escherichia coli Nitrogen Regulatory Genes in the Nitrogen Response of the Azotobacter vinelandiiNifL-NifA Complex

2001 ◽  
Vol 183 (10) ◽  
pp. 3076-3082 ◽  
Author(s):  
Francisca Reyes-Ramirez ◽  
Richard Little ◽  
Ray Dixon
Keyword(s):  
Escherichia Coli ◽  
Signal Transduction ◽  
Nitrogen Control ◽  
Fixed Nitrogen ◽  
Nitrogen Response ◽  
E Coli ◽  
Nitrogen Excess

ABSTRACT The redox-sensing flavoprotein NifL inhibits the activity of the nitrogen fixation (nif)-specific transcriptional activator NifA in Azotobacter vinelandii in response to molecular oxygen and fixed nitrogen. Although the mechanism whereby the A. vinelandii NifL-NifA system responds to fixed nitrogen in vivo is unknown, the glnK gene, which encodes a PII-like signal transduction protein, has been implicated in nitrogen control. However, the precise function of A. vinelandii glnK in this response is difficult to establish because of the essential nature of this gene. We have shown previously that A. vinelandii NifL is able to respond to fixed nitrogen to control NifA activity when expressed inEscherichia coli. In this study, we investigated the role of the E. coli PII-like signal transduction proteins in nitrogen control of the A. vinelandii NifL-NifA regulatory system in vivo. In contrast to recent findings with Klebsiella pneumoniae NifL, our results indicate that neither the E. coli PII nor GlnK protein is required to relieve inhibition byA. vinelandii NifL under nitrogen-limiting conditions. Moreover, disruption of both the E. coli glnB andntrC genes resulted in a complete loss of nitrogen regulation of NifA activity by NifL. We observe that glnB ntrC and glnB glnK ntrC mutant strains accumulate high levels of intracellular 2-oxoglutarate under conditions of nitrogen excess. These findings are in accord with our recent in vitro observations (R. Little, F. Reyes-Ramirez, Y. Zhang, W. Van Heeswijk, and R. Dixon, EMBO J. 19:6041–6050, 2000) and suggest a model in which nitrogen control of the A. vinelandii NifL-NifA system is achieved through the response to the level of 2-oxoglutarate and an interaction with PII-like proteins under conditions of nitrogen excess.

scholarly journals THE ROLE OF PENICILLIN-INDUCED BACTERIAL VARIANTS IN EXPERIMENTAL PYELONEPHRITIS

1967 ◽  
Vol 125 (4) ◽  
pp. 607-618 ◽  
Author(s):  
Richard H. Winterbauer ◽  
Laura T. Gutman ◽  
Marvin Turck ◽  
Ralph J. Wedgwood ◽  
Robert G. Petersdorf
Keyword(s):  
Escherichia Coli ◽  
Renal Medulla ◽  
Round Cell ◽  
Histologic Response ◽  
E Coli ◽  
Round Cell Infiltration ◽  
Kidney Liver

1. After injection into the renal medulla of rats Escherichia coli 06 variants reverted rapidly in vivo in the absence of penicillin. These variants had previously been shown to be stable in vitro. 2. Variants failed to survive following intramedullary injection when animals were receiving penicillin. 3. Late reversion of variants also failed to occur in animals treated with penicillin for only 1 or 2 days. 4. Variants survived and reverted more readily when injected in the renal medulla, compared with liver and spleen. Classical bacteria injected into the kidney, liver, and spleen were recovered in approximately equal numbers. 5. The histologic response to nonreverting variants, medium not containing variants, and killed variants was similar and was characterized by a fibrotic reaction with moderate round cell infiltration. 6. In contrast, the histologic response to reverting variants and to classical E. coli was characterized by an intense, acute, polymorphonuclear leukocytosis typical of acute pyelonephritis.

PROSTACYCLIN (PGI2) FORMATION IN RELATION TO ANAPHYLATOXIN C5a GENERATION DURING RABBIT ENDOTOXIN SHOCK

1987 ◽  
Author(s):  
M Rampart ◽  
H Bult ◽  
A G Herman ◽  
P J Jose ◽  
T J Williams
Keyword(s):  
Blood Pressure ◽  
Arterial Blood Pressure ◽  
Endotoxin Shock ◽  
Rabbit Serum ◽  
Classical Pathway ◽  
E Coli ◽  
Arterial Blood ◽  
Anaphylatoxin C5a

Injection of endotoxin (LPS) in animals, a model for gram-negative septic shock, leads to intravascular activation of the complement system, and is one of the few conditions in which 6-oxo-PGF]CX and thromboxane (TX) B2 (non-enzymic metabolites of PGI2 and TXA2) can be detected in arterial blood. Previously we reported associations between complement activation, PGI2 biosynthesis and LPS-induced hypotension in rabbits. As C5a and C5adesArg trigger endothelial PGI2 formation in vitro, we have now measured the plasma levels of immunoreactive (ir) C5a in relation to generation of PGI2 and changes in arterial blood pressure in LPS shock. Pentobarbitone anaesthethized rabbits received LPS (E. coli 0111:B4, 0.5 mg/kg) or saline via the marginal ear vein. A catheter in the left carotid artery was used to collect blood and to monitor mean arterial blood pressure (MABP). Platelet and leukocyte numbers, haemolytic complement titre (CH50), and plasma ir6-oxo-PGFioc , irTXB2 and irC5a were measured 15 min before and at different times after saline or LPS injection. LPS caused a dose- and time-dependent formation of irC5a in rabbit serum in vitro, predominantly via the classical pathway. LPS also activated complement in vivo, as indicated by about 20 % reduction of CH50 titre (measured after 3h) and a marked increase of arterial irC5a (20-120 ng/ml) in the first 2 to 5 min. After 30 min, irC5a had returned to baseline levels (< 2-5 ng/ml) and remained so up to 3h after injection of LPS. This irC5a peak correlated with a shortlasting initiation of PGI2 release (from < 20 pg/ml up to 550 pg/ml) and a drop in MABP (from about 95 mmHg to 50 mmHg) 2-5 min after LPS. None of these changes occurred after saline injection.In conclusion, LPS activates complement in vivo with concomitant formation of C5a. This peptide may trigger -either directly or after phagocyte activation - endothelial PGI2 biosynthesis, leading to arterial hypotension. This is supported by the suppression of the initial rise of arterial ir6-oxo-PGF1α and hypotension in complement-depleted rabbits. Inhibition of C5a formation or activity may prove to be a meaningful approach to the treatment of septic circulatory shock.

scholarly journals Gout and pseudo-gout-related crystals promote GLUT1-mediated glycolysis that governs NLRP3 and interleukin-1β activation on macrophages

2020 ◽  
Vol 79 (11) ◽  
pp. 1506-1514
Author(s):  
Felix Renaudin ◽  
Lucie Orliaguet ◽  
Florence Castelli ◽  
François Fenaille ◽  
Aurelie Prignon ◽  
...  
Keyword(s):  
Plasma Membrane ◽  
Glucose Uptake ◽  
Aerobic Glycolysis ◽  
Metabolic Reprogramming ◽  
Metabolic Phenotype ◽  
Glucose Transporter 1 ◽  
Gout Flare

ObjectiveMacrophage activation by monosodium urate (MSU) and calcium pyrophosphate (CPP) crystals mediates an interleukin (IL)-1β-dependent inflammation during gout and pseudo-gout flare, respectively. Since metabolic reprogramming of macrophages goes along with inflammatory responses dependently on stimuli and tissue environment, we aimed to decipher the role of glycolysis and oxidative phosphorylation in the IL-1β-induced microcrystal response.MethodsBriefly, an in vitro study (metabolomics and real-time extracellular flux analysis) on MSU and CPP crystal-stimulated macrophages was performed to demonstrate the metabolic phenotype of macrophages. Then, the role of aerobic glycolysis in IL-1β production was evaluated, as well in vitro as in vivo using 18F-fluorodeoxyglucose positron emission tomography imaging and glucose uptake assay, and molecular approach of glucose transporter 1 (GLUT1) inhibition.ResultsWe observed that MSU and CPP crystals led to a metabolic rewiring toward the aerobic glycolysis pathway explained by an increase in GLUT1 plasma membrane expression and glucose uptake on macrophages. Also, neutrophils isolated from human synovial fluid during gout flare expressed GLUT1 at their plasma membrane more frequently than neutrophils isolated from bloodstream. Both glucose deprivation and treatment with either 2-deoxyglucose or GLUT1 inhibitor suppressed crystal-induced NLRP3 activation and IL-1β production, and microcrystal inflammation in vivo.ConclusionIn conclusion, we demonstrated that GLUT1-mediated glucose uptake is instrumental during the inflammatory IL-1β response induced by MSU and CPP crystals. These findings open new therapeutic paths to modulate crystal-related inflammation.

scholarly journals Macrophage Class A Scavenger Receptor-Mediated Phagocytosis of Escherichia coli: Role of Cell Heterogeneity, Microbial Strain, and Culture Conditions In Vitro

2000 ◽  
Vol 68 (4) ◽  
pp. 1953-1963 ◽  
Author(s):  
Leanne Peiser ◽  
Peter J. Gough ◽  
Tatsuhiko Kodama ◽  
Siamon Gordon
Keyword(s):  
Escherichia Coli ◽  
Host Defense ◽  
Bacterial Strain ◽  
Chinese Hamster Ovary Cells ◽  
Culture Conditions ◽  
E Coli ◽  
Class A

ABSTRACT Macrophage class A scavenger receptors (SR-AI and SR-AII) contribute to host defense by binding polyanionic ligands such as lipopolysaccharide and lipoteichoic acid. SR-A knockout (SR-A−/−) mice are more susceptible to endotoxic shock and Listeria monocytogenes infection in vivo, possibly due to decreased clearance of lipopolysaccharide and microorganisms, respectively. We have used flow cytometry to analyze the role of SR-A and other scavenger-like receptors in phagocytosis of bacteria in vitro. Chinese hamster ovary cells stably transfected with human SR-A bound Escherichia coli and Staphylococcus aureus but ingested few organisms. Primary human monocyte-derived macrophages (Mφ) bound and ingested E. coli more efficiently, and this was partially but selectively blocked by the general SR inhibitor, poly(I). A specific and selective role for SR-A was shown, since bone marrow culture-derived Mφ from SR-A−/− mice ingested fewer E. coli organisms than did wild-type cells, while uptake of antibody-opsonized E. coli was unaffected. SR-A-dependent uptake of E. colivaried with the bacterial strain; ingestion of DH5α and K1 by SR-A−/− Mφ was reduced by 30 to 60% and 70 to 75%, respectively. Phagocytosis and endocytosis via SR-A were markedly down-modulated when Mφ were plated on serum-coated tissue culture plastic compared to bacteriologic plastic, where cell adhesion is mediated by SR-A and CR3, respectively. This paper demonstrates that SR-A can bind and ingest bacteria directly, consistent with a role in host defense in vivo, and highlights the importance of the source of the Mφ, bacterial strain, and culture conditions on receptor function in vitro.

scholarly journals Interaction of Bacillus subtilis CsaA with SecA and precursor proteins

2000 ◽  
Vol 348 (2) ◽  
pp. 367-373 ◽  
Author(s):  
Jörg P. MÜLLER ◽  
Jörg OZEGOWSKI ◽  
Stefan VETTERMANN ◽  
Jelto SWAVING ◽  
Karel H. M. VAN WELY ◽  
...  
Keyword(s):  
Bacillus Subtilis ◽  
Specific Interaction ◽  
Membrane Vesicles ◽  
Protein Export ◽  
E Coli ◽  
Bacterium Bacillus Subtilis ◽  
Bacterium Bacillus

CsaA from the Gram-positive bacterium Bacillus subtilis has been identified previously as a suppressor of the growth and protein-export defect of Escherichia coli secA(Ts) mutants. CsaA has chaperone-like activities in vivo and in vitro. To examine the role of CsaA in protein export in B. subtilis, expression of the csaA gene was repressed. While export of most proteins remained unaffected, export of at least two proteins was significantly reduced upon CsaA depletion. CsaA co-immunoprecipitates and co-purifies with the SecA proteins of E. coli and B. subtilis, and binds the B. subtilis preprotein prePhoB. Purified CsaA stimulates the translocation of prePhoB into E. coli membrane vesicles bearing the B. subtilis translocase, whereas it interferes with the SecB-mediated translocation of proOmpA into membrane vesicles of E. coli. The specific interaction with the SecA translocation ATPase and preproteins suggests that CsaA acts as a chaperone that promotes the export of a subset of preproteins in B. subtilis.

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