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)

Although previous studies have demonstrated that microvascular dysfunction and inflammation occur in ischemia-reperfusion injury (IRI), the underlying mechanisms are poorly understood. We hypothesized that T cells could mediate renal vascular permeability (RVP) during IRI. We evaluated renal vascular permeability by extravasation of Evans blue dye from the kidney in CD3, CD4 or CD8 T cell deficient mice as well as in TNF receptor knock out mice in our mouse model of kidney ischemia-reperfusion injury. In wild type mice, RVP was significantly increased at 3 h, peaked at 6 h and declined by 24 h after ischemia. Immunohistochemistry revealed that CD3(+) T cells trafficked into ischemic kidney at 1 h and peaked at 6 h. Gene microarray analysis demonstrated that endothelial-related genes including TNF-alpha were up-regulated in ischemic kidney. The production of TNF-alpha and IFN-gamma protein was increased in CD3 and CD4 T cells from the blood and kidney after ischemia. The rise in RVP after ischemia in wild type mice was attenuated in CD3, CD4 or CD8 T cell deficient mice as well as in TNF receptor knock out mice. The attenuation of RVP in CD3 T-cell deficient mice after ischemia was restored by adoptive transfer of T cells from WT mice. Our data demonstrate that T cells directly contribute to the increased RVP after kidney ischemia-reperfusion, potentially through T cell cytokine production.
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PMID:Effect of T cells on vascular permeability in early ischemic acute kidney injury in mice. 1932 71

Ischemia-reperfusion injury (IRI) triggers an inflammatory cascade that is initiated by the activation of CD1d-restricted iNKT cells. In sickle cell disease (SCD), misshapen erythrocytes evoke repeated transient bouts of microvascular IRI. Compared with C57BL/6 controls, NY1DD mice have more numerous and activated (CD69(+), interferon-gamma(+) [IFN-gamma(+)]) lung, liver, and spleen iNKT cells that are hyperresponsive to hypoxia/reoxygenation. NY1DD mice have increased pulmonary levels of IFN-gamma, IFN-gamma-inducible chemokines (CXCL9, CXCL10), and elevated numbers of lymphocytes expressing the chemokine receptor CXCR3. Treating NY1DD mice with anti-CD1d antibody to inhibit iNKT cell activation reverses baseline pulmonary dysfunction manifested as elevated vascular permeability, decreased arterial oxygen saturation, and increased numbers of activated leukocytes. Anti-CD1d antibodies decrease pulmonary levels of IFN-gamma and CXCR3 chemokines. Neutralization of CXCR3 receptors ameliorates pulmonary dysfunction. Crossing NY1DD to lymphocyte-deficient Rag1(-/-) mice decreases pulmonary dysfunction. This is counteracted by the adoptive transfer of 1 million NKT cells. Like mice, people with SCD have increased numbers of activated circulating iNKT cells expressing CXCR3. Together, these data indicate that iNKT cells play a pivotal role in sustaining inflammation in SCD mice by a pathway involving IFN-gamma and production of chemotactic CXCR3 chemokines and that this mechanism may translate to human disease.
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PMID:NKT cells mediate pulmonary inflammation and dysfunction in murine sickle cell disease through production of IFN-gamma and CXCR3 chemokines. 1943 55

Myocardial ischemia with subsequent reperfusion (MI/R) can lead to significant myocardial damage. Ischemia initiates inflammation at the blood-microvascular endothelial cell interface and contributes significantly to both acute injury and repair of the damaged tissue. We have found that MI/R injury in mice is associated with a cellular immune response to troponin. Myocardial cells exclusively synthesize troponin and release the troponin into the bloodstream following injury. Mucosally administered proteins induce T cells that secrete anti-inflammatory cytokines such as IL-10 and transforming growth factor beta at the anatomical site where the protein localizes. We found that nasal administration of the three subunits of troponin (C, I and T isoforms), given prior to or 1 h following MI/R, decreased infarct size by 40% measured 24 h later. At 1.5 months following MI/R, there was a 50% reduction in infarct size and improvement in cardiac function as measured by echocardiography. Protection was associated with a reduction of cellular immunity to troponin. Immunohistochemistry demonstrated increased IL-10 and reduced IFN-gamma in the area surrounding the ischemic infarct following nasal troponin. Adoptive transfer of CD4+ T cells to mice from nasally troponin-treated mice 1 h after the MI/R decreased infarct size by 72%, whereas CD4+ T cells from IL-10-/- mice or nasally BSA-treated mice had no effect. Our results demonstrate that IL-10-secreting CD4+ T cells induced by nasal troponin reduce injury following MI/R. Modulation of cardiac inflammation by nasal troponin provides a novel treatment to decrease myocardial damage and enhance recovery after myocardial ischemia.
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PMID:Nasal vaccination with troponin reduces troponin specific T-cell responses and improves heart function in myocardial ischemia-reperfusion injury. 1951 97

Reperfusion injury causes liver dysfunction after warm or cold ischemia. Emerging data suggest a role of T cells as mediators in this ischemia/reperfusion (I/R) injury. In the T cells, a part of CD4(+)CD25(+)FoxP3(+) T regulatory cells (Tregs) were reported to facilitate recovery from I/R injury. These Tregs can be induced by TGF-beta in vitro. Interestingly, rapamycin was reported to selectively expand these Tregs in vitro. In the present study, addition of rapamycin to cultures containing TGF-beta further increased the frequency and absolute number of functional CD4(+) Tregs. Using a partial (70%) hepatic warm ischemia model, we investigated the effects of liver function recovery under the treatment of Tregs induced by rapamycin and TGF-beta. The treatment of Tregs significantly reduced serum alanine aminotransferase and aspartate aminotransferase compared to I/R control animals at 24 h after reperfusion (P<0.05). They also significantly attenuated the up-regulation of IFN-gamma and IL-17 compared to the I/R control animals (P<0.05). In conclusion, Tregs ameliorate the biochemical of hepatic I/R injury by preventing proinflammatory cytokines following a warm I/R insult. These data may pave the way to use Tregs as cell therapy to prevent hepatic I/R injury.
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PMID:In vitro induced CD4(+)CD25(+)Foxp3(+) Tregs attenuate hepatic ischemia-reperfusion injury. 1953 64

Hepatic preconditioning has emerged as a promising strategy of activating natural pathways to augment tolerance to liver ischemia-reperfusion (IR) injury. Liver-resident natural killer T (NKT) cells play an important role in modulating the local immune and inflammatory responses. This work was aimed to investigate whether preactivation of NKT cells could provide a beneficial "preconditioning" effect to ameliorate the subsequent hepatic IR injury. To selectively activate NKT cells, C57BL/6 mice were treated intraperitoneally with the glycolipid antigen alpha-galactosylceramide (alpha-GalCer) 1 h prior to hepatic ischemia. Significantly reduced liver IR injury was observed in mice pretreated with alpha- GalCer, and this protective effect was specifically abrogated by a CD1d blocking antibody. Serum TNF-alpha, IFN-gamma, and IL-13 levels were markedly increased shortly after alpha-GalCer injection. Pretreatment with a neutralizing antibody against TNF-alpha or IFN-gamma did not influence the protective effect of alpha-GalCer preconditioning, whereas preadministration of an IL-13 neutralizing antibody completely abolished the effect. Treatment with alpha-GalCer also led to an increased expression of adenosine A2A receptor (A2AR) in the liver, and blockade of A2AR by SH58261 diminished alpha-GalCer pretreatment-mediated attenuation of liver IR injury. In contrast, administration of the selective A2AR agonist CGS21680 reversed the counteracting effect of the IL-13 neutralizing antibody on alpha-GalCer preconditioning. Additionally, alpha-GalCer pretreatment was associated with a decreased neutrophil accumulation in the ischemic liver. These findings provide the first evidence that hepatic preconditioning by preactivation of NKT cells with alpha-GalCer protects the liver from IR injury via an IL-13 and adenosine A2AR-dependent mechanism.
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PMID:Preactivation of NKT cells with alpha-GalCer protects against hepatic ischemia-reperfusion injury in mouse by a mechanism involving IL-13 and adenosine A2A receptor. 1955 59

T cells have been implicated in the early pathogenesis of ischemia reperfusion injury (IRI) of kidney, liver, lung, and brain. It is not known whether Ag-TCR engagement followed by Ag-specific T cell activation participates in IRI. T cell-deficient nu/nu mice are moderately resistant to renal IRI, which can be reversed upon reconstitution with syngeneic T cells. In this study, we found that nu/nu mice reconstituted with DO11.10 T cells, limited in their TCR repertoire, have significantly less kidney dysfunction and tubular injury after renal IRI compared with that in nu/nu mice reconstituted with wild-type T cells having a diverse TCR repertoire. CD4(+) T cells infiltrating ischemic kidneys of nu/nu mice reconstituted with DO11.10 T cells exhibited lower IFN-gamma production than that of wild-type controls. Frequency of regulatory T cells in kidneys of these mice was similar in both DO11.10 T cells and wild-type T cell recipient groups. DO11.10 mice immunized with OVA-CFA had significantly worse kidney function at 24 h after ischemia than those immunized with CFA alone. Thus, without T cell activation, diverse TCR repertoire was important for renal IRI in naive mice. However, once T cells were activated in an Ag-specific manner through TCR in DO11.10 mice, a restricted TCR repertoire no longer limited the extent of kidney injury. Thus, both TCR repertoire-dependent and -independent factors mediate T cell functions in kidney IRI.
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PMID:The role for T cell repertoire/antigen-specific interactions in experimental kidney ischemia reperfusion injury. 1956 Nov 10

Kidney ischemia-reperfusion injury (IRI) is an important contributor to delayed graft function (DGF) and poor outcome of allografts. Small clinical studies suggest a beneficial role for human anti-thymocyte globulin (ATG) in DGF. We investigated the short-term effect of mouse anti-thymocyte globulin (mATG) on kidney warm IRI in mice. We administered either mATG, rabbit immunoglobulin (RIgG), or saline with different dosing schedules in three different IRI models: 30 min bilateral, 60 min bilateral, and 45min unilateral IRI. mATG effectively depleted circulating T cells but had less effect on kidney-infiltrating T cells. There was no difference in serum creatinine levels between groups in each study. Scoring of renal tubular damage and regenerating tubules revealed no difference between groups. The percentage of CD3(+)CD4(-)CD8(-) double-negative (DN) T cells, which were reported to contribute to the pathogenesis of lupus nephritis, increased and the percentages of regulatory T cells and NK cells decreased in the post-ischemic kidneys of mATG treated mice. mATG did not alter the expression of pro-inflammatory cytokines such as IFN-gamma or anti-inflammatory cytokines such as IL-10 in post-ischemic kidneys. mATG treatment, whether initiated before ischemia or immediately after reperfusion, had minimal effects on renal injury following warm IRI in mice.
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PMID:The effect of murine anti-thymocyte globulin on experimental kidney warm ischemia-reperfusion injury in mice. 1968 79

The acute phase cytokines IL-1beta, IL-6 and TNFalpha are produced early during inflammatory processes, including ischemia-reperfusion. The appearance and role of these cytokines in the early inflammation following reperfusion of grafts remain poorly defined. This study investigated the role of TNFalpha in the induction of early leukocyte infiltration into vascularized heart allografts. TNFalpha and IL-6 mRNA levels reached an initial peak 3 h posttransplant and a second peak at 9-12 h with equivalent levels in iso- and allografts. A single dose of anti-TNFalpha mAb given at reperfusion decreased neutrophil and macrophage chemoattractant levels and early neutrophil, macrophage and memory CD8 T-cell infiltration into allografts. Anti-TNFalpha mAb also extended graft survival from 8.6+/-0.6 days to 14.1+/-0.8 days. When assessed on day 7 posttransplant, the number of donor-reactive CD8 T cells producing IFN-gamma in the spleen was reduced almost 70% in recipients treated with anti-TNFalpha mAb. Whereas anti-CD154 mAb prolonged survival to day 21, administration of anti-TNFalpha and anti-CD154 mAb delayed rejection to day 32 and resulted in long-term (>80 days) survival of 40% of the heart allografts. These data implicate TNFalpha as an important mediator of early inflammatory events in allografts that undermine graft survival.
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PMID:Role of TNFalpha in early chemokine production and leukocyte infiltration into heart allografts. 1995 33

Prevention of ischemia-reperfusion injury (IRI) is a challenge in clinical care of the patients with kidney transplants or acute kidney injury, and understanding of the intrinsic mechanisms of resistance to injury in the kidney will lead to a novel therapy. Clusterin, a secreted glycoprotein, is an antiapoptotic protein in cancer cells. Our study is to investigate the role of clusterin in renal IRI. Renal IRI in mice was induced by clamping renal vein and artery for 45 or 50 min at 32 degrees C. Apoptosis of renal tubular epithelial cells (TECs) was determined by FACS analysis. Clusterin expression was examined by Western blot or immunohistochemistry. Here, we showed that clusterin protein was induced in TECs following IRI, and more tubules expressed clusterin in the kidneys following ischemia at higher temperatures. In human proximal TEC HKC-8 cultures, clusterin was upregulated by removal of serum and growth factors in medium and was downregulated by TNF-alpha-IFN-gamma mixture. The levels of clusterin were positively correlated with cell survival in these conditions. Knockdown or knockout of clusterin expression enhanced the sensitivity of TECs to apoptosis. In experimental models of renal IRI, deficiency in clusterin expression worsened the injury, as indicated by a significant increase in renal tissue damage with higher levels of serum creatinine and blood urea nitrogen and by a poorer recovery from the injury in clusterin-deficient mice compared with wild-type mice. Our data indicate that the reduction of inducible expression of clusterin results in an increase in TEC apoptosis in the cultures and renders mice susceptibility to IRI, implying a protective role of clusterin in kidney injury.
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PMID:Loss of clusterin expression worsens renal ischemia-reperfusion injury. 2000 48

Macrophages play a critical role in the pathophysiology of liver ischemia and reperfusion (IR) injury (IRI). However, macrophages that overexpress antioxidant heme oxygenase-1 (HO-1) may exert profound anti-inflammatory functions. This study explores the cytoprotective effects and mechanisms of ex vivo modified HO-1-expressing bone marrow-derived macrophages (BMDMs) in well-defined mouse model of liver warm ischemia followed by reperfusion. Adoptive transfer of Ad-HO-1-transduced macrophages prevented IR-induced hepatocellular damage, as evidenced by depressed serum glutamic-oxaloacetic transaminase (sGOT) levels and preserved liver histology (Suzuki scores), compared to Ad-beta-gal controls. This beneficial effect was reversed following concomitant treatment with HO-1 siRNA. Ad-HO-1-transfected macrophages significantly decreased local neutrophil accumulation, TNF-alpha/IL-1beta, IFN-gamma/E-selectin, and IP-10/MCP-1 expression, caspase-3 activity, and the frequency of apoptotic cells, as compared with controls. Unlike in controls, Ad-HO-1-transfected macrophages markedly increased hepatic expression of antiapoptotic Bcl-2/Bcl-xl and depressed caspase-3 activity. These results establish the precedent for a novel investigative tool and provide the rationale for a clinically attractive new strategy in which native macrophages can be transfected ex vivo with cytoprotective HO-1 and then infused, if needed, to prospective recipients exposed to hepatic IR-mediated local inflammation, such as during liver transplantation, resection, or trauma.
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PMID:Adoptive transfer of ex vivo HO-1 modified bone marrow-derived macrophages prevents liver ischemia and reperfusion injury. 2002 97


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