Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0022116 (ischemia)
 91,303 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The experiments were carried out to explore the interactions between IL-1 beta gene expression, protein level and phospholipase A(2) PLA(2) inhibition after intestinal ischemia/reperfusion injury. Using a rat intestinal ischemia/reperfusion injury model, after collecting the serum, lung lavage, abdomen cavity lavage and important organ tissue samples from control, injury and PLA(2) inhibitor treated groups, IL-1 beta level was measured by radioimmunoassay, and the mRNA expression of IL-1 beta and type II PLA (2)was determined by RT-PCR. After 6 h of injury, the IL-1 beta level in serum was significantly higher than that in the control group; an increase in IL-1 beta was also observed in abdomen cavity lavage 1 or 3 h after injury. IL-1 beta was significantly increased in liver tissue after injury, but was not changed obviously in the lung, kidney and intestinal tissues. IL-1 beta in the lung lavage was significantly higher than that of control group. The mRNA expression of IL-1 beta in lung tissue was increased after injury, but type II PLA(2) mRNA expression was decreased. There were different changes in IL-1 beta level and gene expression after treatment with PLA(2) inhibitor chloroquine, cyclo-oxidase inhibitor indomethacin, or PAF receptor antagonist SR27417 respectively after injury. All these results indicate that after intestinal ischemia/reperfusion injury, the IL-1 beta level and mRNA gene expression are significantly increased, however, the relationship among IL-1 beta, PLA(2) activation and its metabolite release remains to be further elucidated.
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PMID:Interleukin-1beta expression and phospholipase A(2) activation after intestinal ischemia/reperfusion injury. 1193 Feb 37

TNF alpha administration mimics ischemic preconditioning and neutralizing antibodies to TNF alpha and IL-1 beta abolish exercise-induced preconditioning. However, the pharmacology of TNF alpha's cardioprotective effects and associated downstream signaling events has not been delineated. We evaluated the temporal and dose specific requirements of TNF alpha to function as a preconditioning mimetic. Furthermore we postulated that the preconditioning effect of TNF alpha might be orchestrated via sphingolipid signaling. The cardioprotective effect of TNF alpha and the role of sphingolipid signaling were assessed using a classical preconditioning protocol in the isolated perfused rat heart with the measurement of infarct size and contractile function modulation in response to index ischemia and reperfusion. Recombinant TNF alpha at an optimal dose of 0.5 ng/ml mimicked ischemic preconditioning by reducing infarct size by 60%v non-preconditioned ischemia-reperfusion controls (P<0.01). The infarct sparing effect of TNF alpha required a wash-out period prior to the index ischemic-reperfusion. Moreover, the classic ischemic preconditioning antagonist such as 5-hydroxydecanoate abolished TNF alpha preconditioning. An inhibitor of the sphingolipid signaling pathway, N-oleoylethanolamine (NOE, 1 microm) attenuated ischemic and TNF alpha preconditioning. Likewise, cell-permeable C(2)-ceramide and sphingosine 1-phosphate (sphingolipid signaling intermediates) both reproduced the preconditioning cardioprotective phenotype. Finally, TNF alpha and ceramide conferred preconditioning-like cardioprotection against post-ischemic contractile dysfunction and this cardioprotective effect was attenuated by NOE. In contrast, NOE did not reverse ischemic preconditioning enhanced post-ischemic contractile function. In conclusion, TNF alpha activates preconditioning-like tolerance against infarction and contractile dysfunction. This cardioprotection is mediated, in part, via activation of novel sphingolipid signaling intermediates.
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PMID:Identification of a novel role for sphingolipid signaling in TNF alpha and ischemic preconditioning mediated cardioprotection. 1205 55

Interleukin-1 (IL-1) exerts a number of diverse actions in the brain, and it is currently well accepted that it contributes to experimentally induced neurodegeneration. Much of this is based on studies using the IL-1 receptor antagonist, which inhibits cell death caused by ischemia, brain injury, or excitotoxins. Our aim is to determine how and where in the brain IL-1 acts to produce these effects. Most of the neurodegenerative effects of IL-1 are thought to be through IL-1 beta. However, we have data implicating IL-1 alpha in excitotoxic cell death. Furthermore mice lacking both IL-1 alpha and IL-1 beta show dramatically reduced ischemic cell death, whereas deletion of IL-1 alpha or IL-1 beta alone fails to modify damage. It has also been demonstrated that IL-1 exacerbates ischemic injury in mice in the absence of the type I IL-1 receptor, suggesting the existence of novel IL-1 receptors in the brain. IL-1 also dramatically exacerbates neuronal loss in response to intrastriatal administration of the excitotoxin AMPA in the rat brain, an effect accompanied by marked increases in cytokine expression in the frontoparietal cortex, which precedes subsequent cell death in this region. Intrastriatal AMPA also results in limbic seizures that are exacerbated by IL-1, and we hypothesize, therefore, that IL-1 exacerbates cell death through increased seizure activity. Therefore, IL-1 appears to induce acute neurodegeneration through a number of mechanisms.
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PMID:Interleukin-1 in the brain: mechanisms of action in acute neurodegeneration. 1279 45

Ischemic stroke triggers lipid peroxidation and neuronal injury. Docosahexaenoic acid released from membrane phospholipids during brain ischemia is a major source of lipid peroxides. Leukocyte infiltration and pro-inflammatory gene expression also contribute to stroke damage. In this study using lipidomic analysis, we have identified stereospecific messengers from docosahexaenoate-oxygenation pathways in a mouse stroke model. Aspirin, widely used to prevent cerebrovascular disease, activates an additional pathway, which includes the 17R-resolvins. The newly discovered brain messenger 10,17S-docosatriene potently inhibited leukocyte infiltration, NFkappaB, and cyclooxygenase-2 induction in experimental stroke and elicited neuroprotection. In addition, in neural cells in culture, this lipid messenger also inhibited both interleukin 1-beta-induced NFkappaB activation and cyclooxygenase-2 expression. Thus, the specific novel bioactive docosanoids generated in vivo counteract leukocyte-mediated injury as well as pro-inflammatory gene induction. These results challenge the view that docosahexaenoate only participates in brain damage and demonstrate that this fatty acid is also the endogenous precursor to a neuroprotective signaling response to ischemia-reperfusion.
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PMID:Novel docosanoids inhibit brain ischemia-reperfusion-mediated leukocyte infiltration and pro-inflammatory gene expression. 1292

Ischemic preconditioning is a phenomenon that describes how a sublethal ischemic insult can induce tolerance to subsequent ischemia. This phenomenon has been observed after focal or global ischemia in different animal models. However, the hypothesis that bacterial infection might lead to neuronal tolerance to injury has not been investigated. To mimic cerebral bacterial infection, we injected bacterial lipopolysaccharide (LPS) in the right dorsal hippocampus, followed 24 hours later by an excitotoxic lesion using kainic acid in the mouse model. Quantification of lesion size after cresyl violet counterstaining revealed that LPS pretreatment afforded neuroprotection to CA3 neurons against KA challenge. To investigate the events underlying this protection, we studied the cytokine profile induced after LPS injection. Interleukin (IL)-1 beta and transforming growth factor beta 1 (TGF-beta 1) were the main cytokines expressed at 24 hours after LPS injection. Because IL-1 beta has been described as deleterious in acute injury, we decided to investigate the function of TGF-beta 1. An adenovirus expressing a constitutively active form of TGF-beta 1 was injected intracerebrally 1 week before the induction of excitotoxic lesion, and neuronal protection was observed. To confirm the neuroprotective role of TGF-beta 1, the TGF-beta 1 adenovirus was replaced by recombinant human TGF-beta 1 protein and total neuroprotection was observed. Furthermore, the antibody-mediated blocking of TGF-beta 1 action prevented the protective effect of pretreatment with LPS. We have demonstrated in vivo that the cerebral tolerance phenomenon induced by LPS pretreatment is mediated by TGF-beta 1 cytokine.
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PMID:Transforming growth factor-beta 1-mediated neuroprotection against excitotoxic injury in vivo. 1452 28

Our aim was to determine whether cytokine mRNA expression is induced by experimental manipulation including artificial perfusate or ischemia-reperfusion (I/R) in an isolated, perfused rat lung model. Constant pulmonary flow [Krebs-Henseleit solution supplemented with low-endotoxin (LE) or standard (ST) bovine serum albumin 4%, 0.04 ml/g body wt] and ventilation were maintained throughout. Right and left pulmonary arteries were isolated, and the left pulmonary artery was occluded for 60 min and then reperfused for 30 min. Analysis of tumor necrosis factor-alpha, IL-1 beta, IL-6, IL-10, and IFN-gamma mRNA expression by RT-PCR and evaluation of vascular permeability by bronchoalveolar lavage (BAL) fluid albumin content were conducted separately in right and left lung. Both LE and ST groups (each 12 rats) showed increases in vascular permeability by I/R (BAL fluid albumin content: 5.53 +/- 1.55 vs. 15.63 +/- 8.87 and 4.76 +/- 2.71 vs. 16.72 +/- 4.85 mg.ml BAL fluid-1.g lung dry wt-1, mean +/- SD; right vs. left lung in LE and ST groups, P < 0.05 between right and left). Cytokine mRNA expression was significantly higher in the I/R lung than in the control lung in the LE group, whereas it was higher in the control lung in the ST group (P < 0.05). mRNAs of not only proinflammatory but also anti-inflammatory cytokines were expressed in I/R lung, which are expected to aggravate I/R injury. The reversed pattern of cytokine mRNA expression in the ST group was possibly due to the longer perfusion of control lung with perfusate containing endotoxin, which caused no lung damage without I/R.
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PMID:Cytokine mRNA expression in unilateral ischemic-reperfused rat lung with salt solution supplemented with low-endotoxin or standard bovine serum albumin. 1465 1

It has been proposed that mitogen-activated protein kinase (MAPK) pathways may play a role in the regulation of pro-inflammatory cytokines, such as interlukine-1, during cerebral ischemia. Our previous study showed that extracellular-signal-regulated kinases 1 and 2 (ERK 1/2) were activated during focal cerebral ischemia in mice [J. Cereb. Blood Flow Metab. 20 (2000) 1320]. However, the effect of ERK 1/2 activation in focal cerebral ischemia is still unclear. In this study we reported that in vivo phospho-ERK 1/2 expression increased following 30 min of middle cerebral artery occlusion (MCAO) in the mouse brain in both the ischemic core and perifocal regions. Western blot analysis and immunohistochemistry demonstrated that pro-treatment with 1,4-diamino-2,3-dicyano-1,4-bis butadiene (U0126) [J. Biol. Chem. 273 (1998) 18623] could significantly inhibit mouse brain phospho-MEK 1/2 and phospho-ERK 1/2 expression after 1-2 h of MCAO (p<0.05). Compared to the control group of mice, brain infarct volume was significantly decreased after 24 h of MCAO in the U0126-treated mice (27+/-6 vs. 46+/-9 mm(2), p<0.05). Inhibition of the MEK/ERK 1/2 pathway also prevented downstream kinase Elk-1 phosphorylation, and further reduced cytokine IL-1beta mRNA, but not TNFalpha, IL-1alpha, or chemokine MIP-1alpha mRNA expression. Our data demonstrates that in vivo the close linking of MEK 1/2, ERK 1/2, Elk-1, and IL-1 mRNA expression in the cerebral ischemia animals suggests that ERK 1/2 pathway activation is important in pro-inflammatory cytokine IL-1beta signaling, which induces an inflammatory response and exacerbates ischemic brain injury. Inhibiting the ERK 1/2 pathway may therefore provide a novel approach for the reduction of ischemia-induced IL-1beta overexpression.
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PMID:Inhibition of MEK/ERK 1/2 pathway reduces pro-inflammatory cytokine interleukin-1 expression in focal cerebral ischemia. 1467 Jun 31

This review will focus the roles of TNF-alpha, IL-1 alpha, and IL-1 beta in the mammalian testis and in two testicular pathologies, testicular torsion and orchitis. TNF alpha in the testis is produced by round spermatids, pachytene spermatocytes, and testicular macrophages. The type 1 TNF receptor has been found on Sertoli and Leydig cells and numerous studies suggest a paracrine mode of action for TNF alpha in the normal testis. IL-1 alpha has been reported to be produced by Sertoli cells, testicular macrophages, and possibly postmeiotic germ cells. IL-1 receptors have been reported on Sertoli cells, Leydig cells, testicular macrophages, and germ cells suggesting both autocrine and paracrine functions. While these proinflammatory cytokines have important roles in normal testicular homeostasis, an elevation of their expression can lead to testicular dysfunctions. Testicular torsion is a clinical pathology with results in testicular ischemia and surgical intervention is often required for reperfusion. A pivotal role for IL-1beta in the pathology of testicular torsion has been recently described whereby an increase in IL-1beta production after reperfusion of the testis is correlated with the activation of the stress-related kinase, c-jun N-terminal kinase, and ultimately resulting in neutrophil recruitment to the testis and germ cell apoptosis. In autoimmune orchitis, on the other hand, TNF alpha produced by T-lymphocytes and macrophages of the testis has been implicated in the development and progression of the disease. Thus, both proinflammatory cytokines, TNF alpha and IL-1, have significant roles in normal testicular functions as well as in certain testicular pathologies.
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PMID:The role of tumor necrosis factor-alpha and interleukin-1 in the mammalian testis and their involvement in testicular torsion and autoimmune orchitis. 1501 31

We have reported that interleukin-1 beta (IL-1 beta) upregulates cardiac expression of vascular endothelial growth factor (VEGF) and VEGF receptor-2 (VEGFR-2), raising the possibility that IL-1 beta plays an important role in VEGF-mediated neovascularization. In this study, we examined the cellular mechanism for ischemia-induced neovascularization using IL-1 beta knock-out (-/-) mice. Recovery of blood perfusion in ischemic hindlimb in IL-1 beta-/- mice was markedly (43% decrease) impaired as compared with the wild-type mice. CD31(+) vessel numbers and Ki-67(+) neo-capillaries were significantly (P < 0.01) decreased 44% and 68%, respectively. IL-1 beta expression was localized in the capillary vessels in ischemic limb muscles. Ischemia-induced expressions of hypoxia-inducible factor 1 alpha (HIF-1 alpha), VEGF, its receptor VEGFR-2 and vascular cell adhesion molecule-1 (VCAM-1) were markedly inhibited in the IL-1 beta-/- mice. Hindlimb ischemia-induced an increase (1.22% out of total nuclear cell) in CD34(-)/B220(-)/CD3(-)/Flk-1(+) hematopoietic stem cell population in peripheral blood in the wild-type mice, whereas in the IL-1 beta-/- mice such increase was only 0.09%. Injection of IL-1 beta protein into the wild-type mice markedly increased the ratio of the CD34(-)/B220(-)/CD3(-)/Flk-1(+) cell population (from 0.03% to 0.7%) in the peripheral blood associated with an increase in the number of endothelial cells. Such IL-1 beta-mediated increases in cell numbers were blocked by co-injection of anti-VEGF antibody. CD34(-)/B220(-)CD3(-)Flk-1(+) cells trans-differentiated into eNOS- and CD31-expressing endothelial cells in vivo and in vitro. This study demonstrates that IL-1 beta plays a key role in ischemia-induced neovascularization by mobilizing CD34(-)/B220(-)CD3(-)Flk-1(+) endothelial precursor cells in a VEGF-dependent manner as well as by upregulating expressions of VEGF, VEGFR-2 and adhesion molecules on endothelial cells.
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PMID:Mechanism for IL-1 beta-mediated neovascularization unmasked by IL-1 beta knock-out mice. 1508 5

Ischemia and reperfusion injury (IRI) represents the major problem in clinical liver transplantation. We have shown that transcription of signal transducer and activator of transcription 4 (Stat4) plays a key role in the mechanism of hepatic IRI, whereas local induction of interleukin 13 (IL-13) is cytoprotective. The disruption of innate Toll-like receptor 4 (TLR4) signaling prevents mouse livers from undergoing fulminant IRI. This study analyzes in vivo interplay between innate (TLR4) and adaptive (Stat6) immunity in Ad-IL-13 (recombinant adenovirus encoding IL-13) cytoprotection in hepatic IRI. Using a partial 90-min lobar warm ischemia model, groups of wild-type and Stat6-deficient knockout mice were assessed for the severity of hepatocellular damage at 6 hr postreperfusion. Unlike in wild-type mice, treatment of Stat6 knockout recipients with Ad-IL-13 failed to improve hepatic function/histology. The expression of mRNAs encoding tumor necrosis factor alpha/IL-1 beta and IL-2/interferon gamma remained depressed in the wild-type plus Ad-IL-13 group, but not in the Stat6 knockout plus Ad-IL-13 group. Ad-IL-13 increased antioxidant heme oxygenase 1 (HO-1) expression and prevented TLR4 activation in livers of Stat6-competent (wild-type) mice. In contrast, low HO-1 expression and enhanced TLR4 expression were recorded in Stat6 knockout recipients despite Ad-IL-13 therapy. Thus (1) Stat6 is required for Ad-IL-13 to prevent IRI, and (2) depression of TLR4 activation is Stat6 dependent. In conclusion, the Stat6 pathway operates as a key negative regulator in the hepatic inflammatory ischemia-reperfusion response. This study outlines requirements for Ad-IL-13 use to maximize the organ donor pool through the use of liver transplants despite prolonged ischemia.
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PMID:Interleukin 13 gene transfer in liver ischemia and reperfusion injury: role of Stat6 and TLR4 pathways in cytoprotection. 1524 29


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