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

In earlier studies it has been shown that prolactin (PRL) is a stimulating factor for the immune system, and it has been suggested that PRL might antagonize immunosuppressive effects of glucocorticoids. PRL has been reported to affect the cytokine secretion pattern, by elevating cytokine gene expression in macrophages, after the onset of sepsis. It also promotes the antibody response in mice where it increases the production of interferon-gamma (IFN-gamma) and inhibits interleukin-1 (IL-1) production. Due to these properties, PRL might influence the development of autoimmune type 1 diabetes. The aim of the present study was to examine the effects of two drugs; PRL and bromocriptine (BC) in vivo on the development of hyperglycemia and pancreatic insulitis in mice treated with multiple doses of streptozotocin (STZ) (40 mg/kg body weight, i.p.). The dopaminergic agonist BC is known to inhibit PRL secretion. In another set of experiments, the direct effects of PRL on the function of pancreatic islets exposed to STZ in vitro were studied. Mice treated with STZ became gradually hyperglycemic, and concomitant treatment with PRL (4 mg/kg body weight) for 21 days significantly reduced the elevation in blood glucose levels from day 10 onwards (P<0.05). Morphologic examinations of the pancreas on day 21 of mice receiving STZ injections revealed a marked insulitis, but only moderate insulitis in the STZ treated animals given PRL. BC administration (10 mg/kg body weight) in combination with STZ did not significantly affect the elevation in blood glucose levels or the insulitis. PRL or BC administration alone did not change the serum glucose concentration. This study indicates that PRL may affect hyperglycemia in the early phase of autoimmune diabetes. We suggest that it might be due to counteraction of autoimmune immunologic mechanisms and/or enhancement of beta-cell regeneration.
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PMID:Prolactin protects against diabetes induced by multiple low doses of streptozotocin in mice. 1055 72

Tyrosine phosphorylation pathways are essential components of the process of macrophage activation and the resultant production of inflammatory mediators such as tumor necrosis factor (TNF) and nitric oxide (NO). Several lines of evidence suggest that members of the src family of protein tyrosine kinases play important roles in macrophage activation by gram-negative bacterial lipopolysaccharide (LPS) or the cytokine interferon-gamma (IFN-gamma), but targeted disruption of three members of the src family (hck, fgr, and lyn) in mice failed to demonstrate a requirement for these particular kinases in macrophage activation. We report that the pyrazolopyrimidine PP1, a src family-selective tyrosine kinase inhibitor, potently inhibits the production of TNF and inducible nitric oxide synthase (iNOS) in RAW 264.7 murine macrophages stimulated with LPS, rlFN-gamma, or LPS + rIFN-gamma. Furthermore, the tested concentrations of PP1 inhibit LPS- and rlFN-gamma-mediated tyrosine phosphorylation of the hck tyrosine kinase and its putative substrate, vav, but fail to block rlFN-gamma-mediated JAK2 tyrosine phosphorylation. These findings provide additional support for a model of macrophage activation involving one or more src-related kinases. Selective inhibitors of this signaling pathway should be studied in animal models of sepsis.
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PMID:The src family-selective tyrosine kinase inhibitor PP1 blocks LPS and IFN-gamma-mediated TNF and iNOS production in murine macrophages. 1056 9

Animal experiments suggest that hyperproduction of nitric oxide (NO) by the inducible isoform of the enzyme NO synthase (iNOS) may contribute to hypotension, cardiodepression and vascular hyporeactivity in septic shock. Lipopolysaccarides and cytokines, like tumor necrosis factor, interleukin-1 and interferon-gamma, have been shown to induce iNOS in the endothelium, vascular smooth muscle cells, macrophages and different parenchymal cells. In several animal models of septic shock, treatment with inhibitors of NO synthesis has been shown to improve haemodynamic variables and survival. In human septic shock, inhibition of NO synthesis has been shown to alter haemodynamic variables in short term studies. However, a large multicentre study was recently stopped due to increased mortality in patients in septic shock treated with the NO synthase inhibitor NG-monomethyl-L-arginine. The aim of this review is to discuss the role of NO in sepsis and the potential therapeutic implications of NO as a target in treatment of human septic shock. We emphasize that many septic patients have preexisting endothelial dysfunction or lung diseases, which may predispose to severe adverse effects during systemic inhibition of NO synthesis. We also focus on the lack of direct evidence for iNOS expression in human septic shock and on the discrepancy between animal and human data.
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PMID:[Nitric oxide--an important mediator in sepsis?]. 1061 98

The CD14 molecule, which is known to be a receptor for endotoxin, is expressed on monocytes and neutrophils. It is found as a soluble CD14 (sCD14) in circulation, and the plasma level has been shown to be increased in some infectious diseases, including sepsis. To investigate the potential significance of circulating sCD14 in Kawasaki disease (KD), the plasma level of sCD14 was measured using ELISA in patients with KD, patients with a Gram-negative bacterial infection (GNBI) including sepsis, patients with viral infection (VI), and healthy controls. We also analysed CD14 receptor expression in monocytes and neutrophils using flow cytometry and a semiquantitative reverse transcription-polymerase chain reaction. Although KD patients had significantly lower counts of peripheral neutrophils and monocytes than GNBI patients, KD patients had significantly higher levels of sCD14 than GNBI. No significant correlations were observed between sCD14 levels and clinical laboratory values or the cytokine (interferon-gamma, tumour necrosis factor-alpha) levels in the acute phase. The mean intensity of CD14 receptor expression on neutrophils markedly increased in the acute phases of KD and GNBI compared with that in their convalescent phases, while that on monocytes decreased. The expression of CD14 mRNA in neutrophils increased in the acute phases of KD and GNBI, while that in monocytes did not decrease but instead remained quite abundant. The present findings suggest that the elevated level of circulating sCD14 appears to be an important parameter for KD and that sCD14 shedding is accompanied by different kinetics regarding the expression of CD14 antigen and CD14 gene between monocytes and neutrophils.
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PMID:Increased levels of circulating soluble CD14 in Kawasaki disease. 1063 78

Interleukin-12 (IL-12) is thought to play an important role as a modulator of levels of IL-10 and interferon-gamma (IFN-gamma). To address the therapeutic effects of rIL-12 in an endogenous sepsis model in mice, which closely mimics the pathophysiology of septicaemia in man, the effects of rIL-12 on the levels of cytokines such as IL-10 and IFN-gamma, and on the survival of septic mice infected with Pseudomonas aeruginosa PAO1 were examined. First, in the endogenous sepsis model, the serum levels of IFN-gamma and IL-10 remained normal until days 8 and 10, respectively, when significant rises were seen. On day 11, levels of IFN-gamma returned to normal, but levels of IL-10 remained high. Interestingly, the IL-10 serum level reached a maximum 2 days later than the IFN-gamma serum level. In the light of these results, septic mice were given 0.01 microg of rIL-12 by intraperitoneal injection and the serum levels of endogenous cytokines and the survival times were examined. Mice treated with rIL-12 on days 5, 6 and 7 after infection survived significantly longer than control septic mice treated with saline only. Treatment with rIL-12 also led to a significant increase of the serum IFN-gamma level and a decrease of the serum IL-10 level on day 11. These results suggest that rIL-12 exerts therapeutic activity against endogenous sepsis caused by P. aeruginosa by stimulating proinflammatory responses and attenuating anti-inflammatory responses.
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PMID:Prolonged survival of mice with Pseudomonas aeruginosa-induced sepsis by rIL-12 modulation of IL-10 and interferon-gamma. 1093 54

Interleukin-18 (IL-18) is a recently identified immunoregulatory cytokine that shares biochemical features with IL-1beta and acts in part by inducing interferon-gamma (IFN-gamma). Endotoxic bacterial lipopolysaccharide (LPS) (1 or 2 ng/kg) was insufficient to increase plasma IL-18 in five healthy adults measured 3, 12, and 24 hr following challenge. In contrast, in the first 96 hr of admission to the surgical intensive care unit, mean maximal serum IL-18 was elevated (1,122 +/- 259 pg/ml) in nine septic patients compared to six healthy adults (191 +/- 42 pg/ml), P < 0.01). Serum IL-18 concentrations in septic patients did not correlate with other measured inflammatory mediators: tumor necrosis factor, IL-6, IL-10, or secretory leukocyte protease inhibitor. Therefore, IL-18 circulates in healthy adults and is a component of the human systemic inflammatory response. Further, stimuli other than LPS may induce IL-18 production in vivo in human sepsis.
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PMID:Elevation of IL-18 in human sepsis. 1094 29

In this study we investigated the capacity of morphine to modulate expression of cytokines in peritoneal macrophages. Mice were implanted subcutaneously with a 75-mg morphine slow-release pellet, and 48 h later resident peritoneal macrophages were harvested. Control groups received placebo pellets, naltrexone pellets, or morphine plus naltrexone pellets. Adherent cells were stimulated with lipopolysaccharide (LPS: 10 microg/mL) plus interferon-gamma (IFN-gamma: 100 units/mL) to induce cytokine production. After 24 h RNA was extracted for analysis of cytokine mRNA levels by reverse transcriptase-polymerase chain reaction, or supernatants were collected after 48 h for determination of cytokine production by enzyme-linked immunosorbent assay (ELISA). Morphine enhanced mRNA expression of interleukin (IL)-12 p40 and tumor necrosis factor alpha (TNF-alpha) compared with controls, whereas IL-10 levels were unchanged by drug treatment. ELISA data showed that both IL-12 p40 and p70 were increased by morphine. The enhancement of IL-12 at both the mRNA and protein levels was antagonized by naltrexone, indicating that the modulation of this cytokine by morphine is via a classic opioid receptor. These results are particularly interesting in light of our previous observation that 48 h after morphine pellet implantation, the peritoneal cavity is colonized with gram-negative and other enteric bacteria. The enhancement of IL-12 by morphine might be related to morphine-induced sepsis.
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PMID:Morphine enhances interleukin-12 and the production of other pro-inflammatory cytokines in mouse peritoneal macrophages. 1107 13

Most animal studies of cytokine release during sepsis or endotoxemia have used models in which studies are performed during or immediately after surgical stress. In a previous study, we showed that surgical stress as measured by elevated endogenous corticosterone concentrations attenuated the endotoxin-induced tumor necrosis factor alpha (TNFalpha) response. To determine whether surgical stress attenuates the endotoxin-induced interferon-gamma (IFN-gamma) response, chronically catheterized male Sprague-Dawley rats were treated with endotoxin 10 microg/kg immediately after surgery for catheter placement (surgical stress group, SS group) or at least 4 days postoperative (nonstressed group, NS group). We found that peak endotoxin-induced IFN-gamma responses were similar in the SS and NS groups (2094 +/- 315 pg/mL vs. 1863 +/- 307 pg/mL). Baseline corticosterone concentrations were significantly elevated in the SS group compared to the NS group (273.8 +/- 15.2 ng/mL vs. 30.0 +/- 8.5 ng/mL, P < 0.001). Peak TNFalpha concentrations were significantly reduced in the SS group compared to the NS group (5.2 +/- 1.9 ng/mL vs. 69.9 +/- 10.3 ng/mL, P = 0.0002). While peak serum TNFalpha concentrations were inversely related to baseline corticosterone concentrations, there was no correlation between peak IFN-gamma concentrations and baseline corticosterone concentrations or between TNFalpha and IFN-gamma concentrations. We conclude that surgical stress associated with elevated concentrations of endogenous corticosterone does not attenuate the endotoxin-induced IFN-gamma response despite an attenuation of the endotoxin-induced TNFalpha response. Because the effect of stress on different cytokines is varied, studies of sepsis and endotoxemia must account for the effects of experimentally-induced stress on cytokine responses.
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PMID:The effect of surgical stress on the endotoxin-induced interferon-gamma response. 1109 90

The brain and the immune system are the two major adaptive systems of the body. During an immune response the brain and the immune system "talk to each other" and this process is essential for maintaining homeostasis. Two major pathway systems are involved in this cross-talk: the hypothalamic-pituitary-adrenal (HPA) axis and the sympathetic nervous system (SNS). This overview focuses on the role of SNS in neuroimmune interactions, an area that has received much less attention than the role of HPA axis. Evidence accumulated over the last 20 years suggests that norepinephrine (NE) fulfills the criteria for neurotransmitter/neuromodulator in lymphoid organs. Thus, primary and secondary lymphoid organs receive extensive sympathetic/noradrenergic innervation. Under stimulation, NE is released from the sympathetic nerve terminals in these organs, and the target immune cells express adrenoreceptors. Through stimulation of these receptors, locally released NE, or circulating catecholamines such as epinephrine, affect lymphocyte traffic, circulation, and proliferation, and modulate cytokine production and the functional activity of different lymphoid cells. Although there exists substantial sympathetic innervation in the bone marrow, and particularly in the thymus and mucosal tissues, our knowledge about the effect of the sympathetic neural input on hematopoiesis, thymocyte development, and mucosal immunity is extremely modest. In addition, recent evidence is discussed that NE and epinephrine, through stimulation of the beta(2)-adrenoreceptor-cAMP-protein kinase A pathway, inhibit the production of type 1/proinflammatory cytokines, such as interleukin (IL-12), tumor necrosis factor-alpha, and interferon-gamma by antigen-presenting cells and T helper (Th) 1 cells, whereas they stimulate the production of type 2/anti-inflammatory cytokines such as IL-10 and transforming growth factor-beta. Through this mechanism, systemically, endogenous catecholamines may cause a selective suppression of Th1 responses and cellular immunity, and a Th2 shift toward dominance of humoral immunity. On the other hand, in certain local responses, and under certain conditions, catecholamines may actually boost regional immune responses, through induction of IL-1, tumor necrosis factor-alpha, and primarily IL-8 production. Thus, the activation of SNS during an immune response might be aimed to localize the inflammatory response, through induction of neutrophil accumulation and stimulation of more specific humoral immune responses, although systemically it may suppress Th1 responses, and, thus protect the organism from the detrimental effects of proinflammatory cytokines and other products of activated macrophages. The above-mentioned immunomodulatory effects of catecholamines and the role of SNS are also discussed in the context of their clinical implication in certain infections, major injury and sepsis, autoimmunity, chronic pain and fatigue syndromes, and tumor growth. Finally, the pharmacological manipulation of the sympathetic-immune interface is reviewed with focus on new therapeutic strategies using selective alpha(2)- and beta(2)-adrenoreceptor agonists and antagonists and inhibitors of phosphodiesterase type IV in the treatment of experimental models of autoimmune diseases, fibromyalgia, and chronic fatigue syndrome.
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PMID:The sympathetic nerve--an integrative interface between two supersystems: the brain and the immune system. 1112 11

Endotoxemia is associated with a systemic inflammatory response leading to organ-specific leukocyte recruitment and tissue injury. Chemokine expression has been demonstrated in various models of sepsis and may mediate tissue infiltration with inflammatory cells. In this study we examined expression of the C-X-C chemokine interferon-gamma-inducible protein-10 (IP-10), a potent T-lymphocyte chemoattractant, in a canine model of endotoxemia and investigated mechanisms of cytokine-mediated IP-10 induction in endothelial cells. Control canine tissues showed negligible expression of IP-10 message, with the exception of the spleen. Endotoxemic dogs demonstrated a robust induction of IP-10 mRNA in the heart, lung, kidney, liver, and spleen. Immunohistochemical studies indicated that IP-10 was predominantly localized in cardiac venular endothelial cells, bronchial epithelial cells, renal mesangial cells, and in the splenic red pulp of endotoxemic dogs. In addition, IP-10 expression was associated with T-lymphocyte infiltration in canine tissues. Tumor necrosis factor-alpha (TNF-alpha) and interleukin-1 beta (IL-1 beta) induced a marked upregulation of IP-10 message in canine venular endothelial cells. IP-10 expression in TNF-alpha-stimulated endothelial cells peaked at 6 h of stimulation and returned to baseline levels after 24 h. In addition, macrophage colony-stimulating factor (M-CSF) induced a dose-dependent induction of IP-10 mRNA in canine endothelial cells. M-CSF-mediated IP-10 expression peaked after 6 h of incubation and returned to baseline levels after 24 h. Canine endotoxemia is associated with a robust early expression of IP-10 in multiple tissues. IP-10 induction may be important in regulating lymphocyte recruitment and function. TNF-alpha, IL-1 beta, and M-CSF are potent inducers of IP-10 in canine endothelial cells and may indirectly mediate lymphocyte chemotaxis and activation in inflammatory processes.
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PMID:Induction of the synthesis of the C-X-C chemokine interferon-gamma-inducible protein-10 in experimental canine endotoxemia. 1115 48


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