Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UMLS:C0243026 (sepsis)
 52,417 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The influence of granulocyte-macrophage colony-stimulating factor (GM-CSF) and IFN-gamma on the restoration of impaired TNF-alpha release in LPS-desensitized mice or their refractory macrophages was investigated. Mice pretreated with GM-CSF or IFN-gamma (50 microg/kg i.v.) and injected with 3 mg/kg LPS i.p. displayed increased plasma TNF-alpha levels compared with LPS controls. IL-10 was marginally up-regulated by GM-CSF but abrogated by IFN-gamma pretreatment. LPS-tolerant mice (30 microg/kg LPS i.p., -24 h) showed an attenuated plasma TNF-alpha and IL-10 response to LPS and survived LPS shock. Pretreatment of such mice with GM-CSF or IFN-gamma restored the previously impaired TNF-alpha response. In cultures of murine monocyte/macrophage-containing cell populations, i.e., alveolar, peritoneal, spleen, bone marrow cells, or blood, the presence of GM-CSF or IFN-gamma (10 ng/ml) resulted in an enhanced release of TNF-alpha initiated by 1 microg/ml LPS. Cells from LPS-tolerant mice showed a diminished responsiveness to LPS. However, when exposed to GM-CSF or IFN-gamma ex vivo, their TNF-alpha response to LPS was partially restored. These findings characterize GM-CSF and IFN-gamma as potent enhancers of LPS-induced TNF-alpha production in normal as well as in experimentally immunocompromised mice and provide the rationale for further experiments to explore the pharmacologic use of these cytokines for restoration of immunocompetence in sepsis-associated immunosuppression.
 ...
PMID:Granulocyte-macrophage colony-stimulating factor and IFN-gamma restore the systemic TNF-alpha response to endotoxin in lipopolysaccharide-desensitized mice. 905 23

The effects of lisofylline [(R)-1-(5-hydroxyhexyl)-3,7-dimethylxanthine] (LSF), an inhibitor of de novo phosphatidic acid (PA) generation, on sepsis-induced acute lung injury was studied using Hanford minipigs weighing 18 to 25 kg. Sepsis was induced by an intravenous infusion of Pseudomonas aeruginosa (1 x 10(6)/colony-forming units/kg/min over 2 h). Saline was used as the control vehicle. Six groups were studied: saline control group (SALINE: n = 5); sepsis control group (SEPSIS: n = 5); LSF control group (LSF: n = 5), which received a 25-mg/kgbolus of LSF 30 min before time zero followed by continuous infusion of 10 mg/kg/h throughout the study; LSF-treated septic groups, which were treated with LSF 30 min prior to sepsis (Pre: n = 5), 1 h postonset (Post-1 h: n = 8) or h postonset (Post-2 h: n = 8) of the bacterial infusion. Hemodynamics PaO2, neutrophil counts, and plasma porcine tumor necrosis factor-alpha concentrations were monitored for 6 h. After the minipigs were killed, lung tissue was sampled to measured wet-to-dry weight ratio (W/D), tissue albumin index (TAI), thiobarbituric acid-reactive material content (TBARM), and myeloperoxidase (MPO) activity. Compared with the SALINE group, the SEPSIS group showed significant systemic hypotension, pulmonary hypertension, arterial hypoxemia, neutropenia, and increase in TNF-alpha, MPO activity, W/D, TBARM, and TAI. LSF treatment attenuated sepsis-induced pulmonary hypertension, neutropenia, and hypoxemia, and increased MPO activity and lung injury measurements in the Pre and Post-1 h groups, but its efficacy was blunted in the Post-2 h group. Plasma TNF-alpha was decreased only in the Pre group. Thus, inhibition of intracellular PA generation through de novo pathways attenuates sepsis-induced acute lung injury.
 ...
PMID:The effects of post-treatment with lisofylline, a phosphatidic acid generation inhibitor, on sepsis-induced acute lung injury in pigs. 911 28

Since pentoxifylline (PTX) was recently recognized as a substance with antiinflammatory capacities, we studied the in vivo and in vitro effect of PTX on the expression of the intercellular adhesion molecule-1 (ICAM-1) on human monocytes. For this purpose four healthy volunteers were treated with PTX (5 x 400 mg/day) for 2 days. Monocytes were isolated before and after PTX treatment and ICAM-1 expression was investigated. As shown by fluorescence-activated cell sorter (FACS) analysis, cultured monocytes isolated after oral application of PTX expressed significantly decreased amounts of ICAM-1 when compared with monocytes collected prior to oral PTX application. Northern blot analysis revealed reduced amounts of ICAM-1 mRNA in monocytes derived from volunteers after oral PTX treatment in comparison with monocytes isolated before oral PTX administration. Similarly, in monocytes treated with PTX (200 micrograms/ml) in vitro ICAM-1 was found decreased both at the protein and mRNA level in comparison with untreated cells. The inhibitory effect of PTX on ICAM-1 expression in monocytes could be reversed by the addition of exogenous tumour necrosis factor-alpha (TNF-alpha; 200 U/ml) suggesting that ICAM-1 down-regulation is mediated secondary to TNF-alpha suppression by PTX. The specific role of TNF-alpha in mediating ICAM-1 expression in cultured monocytes could be confirmed by the finding that a neutralizing anti-TNF-alpha antibody partially down-regulated ICAM-1 expression. The observed suppressive in vivo and in vitro effects of PTX on ICAM-1 expression in monocytes may contribute to the recently described antiinflammatory effects of PTX, e.g. in sepsis or allergic contact dermatitis.
 ...
PMID:Pentoxifylline in vivo and in vitro down-regulates the expression of the intercellular adhesion molecule-1 in monocytes. 915 52

IFN-gamma receptor-deficient (IFN-gammaR -/-) mice were used to study the innate immune responses during infection with Listeria monocytogenes. Mutant mice were unable to limit bacterial growth and died of sepsis even with an infection dose of 70 Listeria. At day 2, they showed an exacerbated listeriosis and mice succumbed to infection before the onset of an effective specific immunity, demonstrating a defective innate immunity. Recruitment and extravasation of phagocytic cells to infected organs was present and dominated by neutrophils. However, during the early course of infection, mutant mice responded by an elevated inflammatory type 1 cytokine response, as determined by IL-12, IFN-gamma, TNF-alpha, and IL-1alpha-specific RNA expression. Induction of inducible nitric oxide synthase was present and also increased in mutant mice. Interestingly, IFN-gammaR -/- neutrophils expressed substantial TNF-alpha- and IL-1alpha-specific RNA, suggesting a substantial contribution in the overall inflammatory cytokine response. In contrast, IFN-gammaR -/- macrophages showed reduced MHC class II surface expression levels and impaired TNF-alpha and IL-1alpha but normal IL-6 production after restimulation with heat-killed L. monocytogenes. Moreover, IFN-gammaR -/- macrophages showed defective listericidal activities. In contrast to normal macrophages, Listeria escaped rapidly from the phagosome in IFN-gammaR -/- macrophages to the cytoplasm, where they productively survived. In conclusion, these data suggest that IFN-gammaR signaling activates yet unknown functions in macrophages, preventing Listeria-induced escape from the phagosome and consequent killing of the invader. Together with the impaired cytokine responses, these macrophage defects seem to be responsible for the dramatic susceptibility during innate immunity, whereas predominant neutrophil responses mediate limited protective role in mutant mice.
 ...
PMID:Impaired macrophage listericidal and cytokine activities are responsible for the rapid death of Listeria monocytogenes-infected IFN-gamma receptor-deficient mice. 916 49

Activation of the resident macrophage populations of the reticuloendothelial system is a key component of the complex pathophysiology of sepsis. Macrophage activation leads to production and secretion of inflammatory mediators such as cytokines, vasoactive substances, free radicals, and chemokines, which have been associated with high morbidity and mortality in the septic patient. The goal of the present study was to determine whether antioxidants could suppress Kupffer cell activation at points beyond the initiation of activation. Kupffer cells were studied since they are central to the clearance of bacteria and endotoxins, and have been associated with hepatocellular dysfunction in sepsis. Cells were activated with 10 ng/ml LPS for various times whereupon N-acetylcysteine (30 mM) and alpha-tocopherol (50 microM) were added. Steady state levels of cytokine mRNA, activation of nuclear factor-kappaB, and TNF-alpha secretion were determined when expression was maximal in control cells. The results of this study show that antioxidants can be used to suppress Kupffer cell activation at points beyond the initiation of activation. Furthermore, we show that N-acetylcysteine-mediated inhibition of activation requires secondary protein synthesis, but does not modulate IkappaB-alpha mRNA expression. The inhibitory effect of these drugs occurs at the very earliest steps of the LPS signal transduction cascade as it is currently understood. The results of the present study suggest that the inflammatory response to sepsis may be controlled through appropriate antioxidant therapy.
 ...
PMID:N-acetylcysteine and alpha-tocopherol reverse the inflammatory response in activated rat Kupffer cells. 916 63

Dysfunctioning of the heart forms part of the multiple organ dysfunction syndrome (MODS) in sepsis and SIRS. This acute septic cardiomyopathy is often underestimated in degree and relevance, although yet in fact 10% of all sepsis fatalities are due to intractable heart failure. This potentially reversible cardiomyopathy is characterized by a considerable pump failure, is not primarily ischemic, coronary blood flow being normal or even enhanced; left and right ventricle are enlarged as a consequence of an increased ventricular compliance. Damage of the heart can further be aggravated in case of an additional right ventricular impairment due to pulmonary hypertension in ARDS. SIRS-cardiomyopathy in non-infectious MODS has common traits with acute septic cardiomyopathy. The pathogenesis of heart disease in sepsis and SIRS is multifactorial, the endotoxin/TNF-alpha/NO/cGMP-cascade representing a main negative inotropic axis. Therapy of acute septic cardiomyopathy and SIRS-cardiomyopathy at present still is mainly symptomatic (volume substitution, inotropic/vasoactive agents), causal therapeutic principles are, however, put to test in the context of a comprehensive concept of causal sepsis treatment.
 ...
PMID:[The heart in infection and MODS (multiple organ dysfunction syndrome)]. 917 72

The overzealous production of proinflammatory cytokines in sepsis can result in shock, multiorgan dysfunction, and even death. In this study, we assessed the role of monocyte chemoattractant protein-1 (MCP-1) as a mediator of sepsis in endotoxin-challenged mice. Intraperitoneal administration of LPS to CD-1 mice induced a substantial time-dependent increase in MCP-1 in plasma, lung, and liver. The passive immunization of mice with rabbit antimurine MCP-1 antiserum 2 h before endotoxin administration resulted in a striking increase in LPS-induced mortality from 10% in control animals to 65% in anti-MCP-1-treated animals. Importantly, the administration of anti-MCP-1 antibodies to endotoxin-challenged mice resulted in increases in peak TNF-alpha and IL-12 levels, and also in a trend toward decreased serum levels of IL-10. Conversely, the administration of recombinant murine MCP-1 intraperitoneally significantly protected mice from endotoxin-induced lethality, and resulted in an increase in IL-10 levels, a decrease in IL-12 levels, and a trend toward decreased levels of TNF. In conclusion, our findings indicate that MCP-1 is a protective cytokine expressed in murine endotoxemia, and does so by shifting the balance in favor of antiinflammatory cytokine expression in endotoxin-challenged animals.
 ...
PMID:MCP-1 protects mice in lethal endotoxemia. 918 4

Endotoxin (LPS) can cause hepatocellular injury under several circumstances, and leukotrienes have been implicated as a contributing factor. Since ion channel activation has been associated with cytotoxicity, the aim of this study was to determine the circumstances under which LPS and/or leukotrienes activate ionic conductances in hepatocytes. LPS treatment of rats increased Cl- conductance in hepatocytes from 232+/-42 to 1236+/-134 pS/pF. Voltage dependence and inhibitor specificity of this conductance were similar to that of a swelling-activated Cl- conductance, and internal dialysis with nucleoside analogues suggested control by an inhibitory G protein. The lipoxygenase inhibitor nordihydroguaiaretic acid, the specific leukotriene D4 (LTD4) receptor antagonist MK-571, and the 5-lipoxygenase activating protein inhibitor MK-886 all significantly inhibited the conductance. Intracellular dialysis with LTD4 (1.5 microM) elevated intracellular Ca2+ from 143+/-6.5 to 388+/-114 nM within 6 min and stimulated an outwardly rectifying conductance from 642+/-159 to 1669+/-224 pS/pF (n = 9, P < 0.001). In hepatocytes prepared from untreated rats, this concentration of intracellular LTD4 neither raised intracellular Ca2+ nor activated the conductance. The LTD4 response could be induced in normal hepatocytes by culture with either conditioned medium from LPS-treated macrophages or purified TNF-alpha. In conclusion, intracellular LTD4 activates a chloride conductance in hepatocytes isolated from rats treated with LPS or primed in vitro with TNF-alpha. Changes in the hepatocellular accumulation of leukotrienes therefore mediate channel activation and may contribute to liver injury during sepsis and other inflammatory conditions.
 ...
PMID:Leukotriene D4 activates a chloride conductance in hepatocytes from lipopolysaccharide-treated rats. 918 15

Previous studies indicate a profound suppression of tumour necrosis factor alpha (TNF-gamma), IL-1 beta and IL-6 release capacity by peritoneal macrophage (PM phi), splenic macrophage (SM phi) and Kupffer cells (KC) during late sepsis. Such a loss of functional capacity may reduce the animal's ability to ward off infection. Prolactin is known to enhance monocyte, T- and B-lymphocyte immune responses under normal conditions and has beneficial effects on cell-mediated immunity after haemorrhage. In the respect, the dopamine antagonist, metoclopramide, has been reported to increase circulating prolactin levels. Nonetheless, it remains unknown whether prolactin or metoclopramide have any salutary effect on macrophage (M phi) cytokine gene expression following sepsis. To study this, male C3H/HeN mice were subjected to sepsis and immediately thereafter were treated with prolactin (100 micrograms/25 g body weight, s.c.), metoclopramide (100 micrograms/100 g BW, s.c.) or given saline. PM phi, SM phi and KC (only SM phi and KC in metoclopramide-treated animals) were isolated at 24 h after sepsis. The monolayers were stimulated with or without LPS 10 micrograms/ml for 1 h in vitro. Total RNA was extracted and mRNA was detected by semi-quantitative reverse transcription polymerase chain reaction (RT-PCR). A significant depression of constitutive and inducible mRNA levels of IL-1 beta, IL-6 and TNF-alpha in all three M phi populations were observed, when compared with shams (with exception of KC IL-6 mRNA in unstimulated cells). Prolactin as well as metoclopramide treatment after the onset of sepsis caused significant elevation of constitutive and inducible cytokine gene expression in all macrophages examined. Thus, prolactin and metoclopramide enhance the depressed M phi gene expression and may be useful in improving cell-mediated immunity during sepsis.
 ...
PMID:Effects of prolactin and metoclopramide on macrophage cytokine gene expression in late sepsis. 919 78

Early release of macrophage-derived proinflammatory cytokines, such as tumor necrosis factor (TNF), interleukin (IL)-1, and IL-6, are important in the pathogenesis of septic shock and multisystem organ failure in various models of sepsis. IL-10 is a mediator that inhibits cytokine release from activated macrophages. The aim of this study was to determine if IL-10 would decrease serum cytokine elevation in a murine model of cecal ligation and puncture (CLP). CLP in animals is a model that closely mimics the physiologic changes seen in human sepsis. Four groups of 14 female Swiss-Webster mice were used. Group 1 underwent laparotomy alone, groups 2, 3, and 4 underwent laparotomy and CLP. Groups 1 and 2 received intraperitoneal (IP) saline injections to serve as control vehicle. Group 3 (prophylactic) received 10,000 U IP IL-10 1 hr prior to CLP and every 3 hr thereafter. Group 4 (therapeutic) received 10,000 U IP IL-10 1 hr following CLP and every 3 hr thereafter. Animals were sacrificed at 3 and 9 hr following CLP. Serum TNF-alpha, IL-1 beta, and IL-6 were determined by enzyme-linked immunosorbent assay (ELISA), CLP produced a significant rise in serum TNF,IL-6, and IL-1 in untreated controls. Prophylactic or therapeutic administration of IL-10 significantly attenuated this early rise in serum cytokines. These results support the hypothesis that (1) CLP produces an early systemic rise in macrophage-derived cytokines and (2) IL-10 given either before or after the onset of CLP-induced intraabdominal infection and sepsis is able to inhibit this early release of macrophage-derived systemic mediators. IL-10 has potential clinical benefits in the therapeutic management of intraabdominal infection and sepsis.
 ...
PMID:Interleukin-10 prevents early cytokine release in severe intraabdominal infection and sepsis. 923 83


<< Previous 1 2 3 4 5 6 7 8 9 10 Next >>