Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0151744 (myocardial ischemia)
 31,282 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The time course of endothelial P-selectin, ICAM-1, and E-selectin expression was studied in a feline model of myocardial ischemia and reperfusion. Cats were subjected to 90 min of myocardial ischemia followed by 0, 10, 20, 60, 150, or 270 min of reperfusion. At the end of reperfusion, the coronary vasculature was examined immunohistochemically to localize monoclonal antibodies (mAbs) PB1.3, RR1/1, and Cy1787 directed against P-selectin, ICAM-1, and E-selectin, respectively. Immunohistochemical localization for P-selectin, recognized by mAb PB1.3, was maximally expressed 20 min after reperfusion in 60 +/- 6% of coronary venules (P < 0.05 compared to non-reperfused controls), and covered 59 +/- 3% of the endothelial cell perimeter of immunostained coronary venules. Immunolocalization of mAb PB1.3 gradually declined at 60, 150, and 270 min of reperfusion. Immunohistochemical localization of mAb RR1/1 (anti-ICAM-1) in endothelial cells of coronary venules was observed to a modest extent in non-ischemic myocardium and at 10, 20, and 60 min of reperfusion, but was significantly increased following 150 and 270 min of reperfusion (P < 0.05 compared non-reperfused controls). At 270 min post-reperfusion, mAb RR1/1 was seen in 50 +/- 4% of coronary venules. Endothelial immunolocalization of mAb Cy1787 (anti-E-selectin) was only observed in 13 +/- 1 and 14 +/- 3% of coronary venules after 150 and 270 min of reperfusion, respectively, suggesting that pronounced expression of E-selectin does not occur within 270 min after reperfusion. These results demonstrate sequential expression of three major endothelial cell adherence molecules in situ following myocardial ischemia and reperfusion. The timing of endothelial cell expressed P-selectin and ICAM-1 could coordinate neutrophil trafficking during the early stages of reperfusion.
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PMID:Time course of coronary vascular endothelial adhesion molecule expression during reperfusion of the ischemic feline myocardium. 753 Feb 83

Marine fish consumption is known to reduce mortality from ischemic heart disease. The use of fish oil as a dietary supplement, however, is not universally recommended. In large doses, fish oil reduces plasma cholesterol and triacylglycerol but increases low density lipoprotein (LDL) levels and the potential for free radical generation and bleeding. Moderate marine fish consumption is known to reduce mortality without altering commonly measured variables, i.e., plasma cholesterol levels, in vitro platelet aggregation, and bleeding times. In swine, we observed that monocyte adhesions and platelet clumps over the lesion surface of proximal left anterior descending (LAD) coronary arteries are markedly reduced when an atherogenic diet was supplemented with cod-liver oil, even when the cholesterol levels were equalized with the untreated group. These findings suggest that fish oil is hypothrombogenic. We developed an in vitro assay to delineate the mechanism whereby fish oil reduced monocyte-endothelial cell interactions in vivo. The effects of supplementing the culture medium with different fatty acids on adhesions between lipopolysaccharide (LPS) stimulated swine aortic endothelial cells (SAEC) and the human monocyte-like cell line, U937, was investigated in a 10 minute adhesion assay at 37 degrees C. Exposure of SAEC for 6 hours to media containing 50-200 microMs eicosapentaenoic (EPA), stearic, oleic, linoleic, and arachidonic acid, respectively, revealed that only EPA reduced U937-SAEC adhesion. Exposure of U937 to EPA also reduced adhesions. EPA was not effective when added to the SAEC more than 2 hours after they were stimulated with LPS. Exposure of human umbilical vein endothelial cells (HUVEC) to EPA reduced the expression of VCAM-1, ELAM-1, and ICAM-1 after 5 hours of stimulation with LPS. These results suggest that EPA may functionally impair the induction/expression of adhesion molecules.
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PMID:Fish oil, atherogenesis, and thrombogenesis. 753 28

In this study we have assayed the pathophysiological role of intercellular adhesion molecule (ICAM-1), a cytokine-inducible adhesion molecule, in a model of ischaemia reperfusion in the rat. Anaesthetized rats were subjected to occlusion (1 h) of the left main coronary artery followed by reperfusion (1 h). Sham myocardial ischaemia-reperfusion rats (Sham MI/R) were used as controls. Myocardial ischaemia plus reperfusion in untreated rats decreased survival rate, produced a marked myocardial necrosis, increased serum creatine phosphokinase activity, and cardiac myeloperoxidase activity (a marker enzyme commonly used to assess polymorphonuclear leukocyte accumulation). Furthermore, rats subjected to myocardial ischaemia-reperfusion showed an increased pressure rate index, studied as a quantitative means for assessing myocardial oxygen demand. Treatment with monoclonal anti-rat ICAM-1 (1 mg/kg i.v.), 3 h before occlusion of the left main coronary artery, significantly lowered serum creatine phosphokinase activity, blunted leukocyte accumulation and protected the myocardium from injury subsequent to ischaemia and reperfusion injury. These investigations have revealed that ICAM-1 is a critical adhesion molecule in the pathogenesis of ischaemia-reperfusion injury. In addition these results suggest that the use of monoclonal antibodies raised against ICAM-1 can represent a useful tool for the prevention of ischaemia-reperfusion damage.
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PMID:Antibodies against intercellular adhesion molecule 1 protect against myocardial ischaemia-reperfusion injury in rat. 785 76

When activated neutrophils are recruited and bind to endothelial tissues, they release leukotrienes, proteolytic enzymes, and free radicals. The latter has been implicated in myocardial stunning following periods of ischemia and reperfusion, as may occur following cardiopulmonary bypass (CPB). The neutrophil surface complex CD11/CD18 promotes the neutrophil-endothelial adhesion process. Monoclonal antibodies have been developed that can block neutrophil adhesion to the endothelium by preventing CD11/CD18 binding to adhesion molecules (ICAM-1 or ELAM-1) located on endothelial cells. We used monoclonal IgG antibody 60.3 to block neutrophil adherence and thereby potentially reduce myocardial stunning. Pretreatment of rabbits subjected to myocardial ischemia/reperfusion with either monoclonal 60.3 or saline resulted in only a small increase in the rate of recovery of preload recruitable stroke work index during reperfusion. More severe occlusion may have been needed to see significant results. We also evaluated the effects of anti-neutrophil therapy in animal models of CPB. Rhesus monkeys were subjected to deep hypothermia and CPB, followed by 24 hours of fluid resuscitation. Animals receiving monoclonal 60.3 (N = 3) showed less weight gain, less infused resuscitative fluid, and higher terminal hematocrit and PaO2 than controls (N = 3). Antineutrophil therapy may prevent multiorgan system failure in certain high risk patients.
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PMID:Potential role of neutrophil anti-adhesion therapy in myocardial stunning, myocardial infarction, and organ dysfunction after cardiopulmonary bypass. 846 23

Intercellular adhesion molecule-1 (ICAM-1) is a major ligand for 2 members of the CD18 family of leukocyte integrin adhesion molecules and mediates adhesion between leukocytes and stimulated endothelial cells. We examined plasma soluble ICAM-1 (sICAM-1) levels in 30 patients with acute myocardial infarction (AMI) within 6 h of symptom onset, 21 patients with unstable angina (UA), 35 patients with stable exertional angina (SEA) and 21 control subjects. Plasma sICAM-1 levels (ng/ml) were significantly higher in both the acute and chronic phases of AMI and in the UA group than in the SEA and the control groups (195 +/- 14, 198 +/- 16 in the acute and chronic phases of AMI, 188 +/- 11 in the UA group vs 142 +/- 7 in the SEA group, 141 +/- 10 in the control group, p < 0.01). Plasma sICAM-1 levels were significantly higher in AMI patients when preceded by unstable angina than when not preceded by unstable angina at any point over the time course except 1 week after admission (p < 0.01 vs admission, 12 h, 2 days, 3 days, 5 days, 2 weeks, 3 weeks. p < 0.05 vs 24 h). These results suggest that the increase in sICAM-1 is associated with repeated episodes of myocardial ischemia and reperfusion not leading to myocardial necrosis. The increase in sICAM-1 may play an important role as an inflammatory component in the pathogenesis of the ischemic myocardium.
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PMID:Increased plasma soluble intercellular adhesion molecule-1 levels in patients with acute myocardial infarction. 929 3

Intercellular adhesion molecule-1 (ICAM-1) plays an important role in the pathogenesis of either human and experimental myocardial ischaemia. Tacrolimus, formerly known as FK506, has been previously shown to display cardioprotective effects on experimental ischaemia/reperfusion-induced myocardial damage. This study investigated whether cardioprotection induced by tacrolimus in myocardial ischaemia-reperfusion (MI/R) injury might be due to inhibition of the nuclear factor kappa B (NF- kappaB) that in turn causes reduced cardiac ICAM-1 expression and blunted polymorphonuclear leukocyte accumulation. Anaesthetized rats were subjected to total occlusion (45 min) of the left main coronary artery followed by 5 h reperfusion (MI/R). Sham myocardial ischaemia-reperfusion rats (Sham MI/R) were used as controls. Myocardial necrosis, myocardial myeloperoxidase activity, serum creatine kinase (CK) activity, cardiac mRNA for ICAM-1 reverse-transcriptase polymerase chain reaction, the inhibitory protein of NF- kappaB I kappaB alpha (Western blot analysis) in the myocardium-at-risk, and left ventricle d P/d t(max)were evaluated. Myocardial ischaemia plus reperfusion in untreated rats produced marked myocardial necrosis, increased serum CK activity and myeloperoxidase activity (MPO, a marker of leukocyte accumulation) both in the area at risk and in the necrotic area, and reduced the left ventricle dP/d t(max). Furthermore, inhibitory protein I kappaB alpha levels decreased, and cardiac mRNA for ICAM-1 increased, after 0.5 and 5 h of reperfusion, respectively. Administration of tacrolimus (25, 50 and 100microg/kg as an i.v. infusion 5 min after reperfusion) lowered myocardial necrosis and myeloperoxidase activity in the area at risk and in necrotic area, decreased serum CK activity, increased left ventricle dP/d t(max), reduced the loss the of inhibitory protein I kappaB alpha and blunted the message for ICAM-1. The present data suggest that tacrolimus blocks the early activation of the transcription factor NF- kappaB, suppresses ICAM-1 gene activation, reduces leukocyte accumulation and protects against myocardial ischaemia-reperfusion injury.
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PMID:Tacrolimus limits polymorphonuclear leucocyte accumulation and protects against myocardial ischaemia- reperfusion injury. 1073 42

Myocardial damage due to reperfusion of ischemic tissue is caused primarily by infiltrating neutrophils. Although leukocyte beta2 integrins (CD18) play a critical role, significant neutrophil emigration persists when CD18 is neutralized or absent. This study examined the role of leukocyte beta1 integrin (alpha4) and its endothelial ligand VCAM-1 in CD18-independent neutrophil migration across cardiac endothelium. In a mouse model of myocardial ischemia and reperfusion, we show that compared with wild-type mice, neutrophil infiltration efficiency was reduced by 50% in CD18-null mice; in both types of mice, myocardial VCAM-1 staining increased after reperfusion. In wild-type mice, antibodies against CD18, ICAM-1 (an endothelial ligand for CD18), or VCAM-1 given 30 minutes before ischemia did not block neutrophil emigration at 3 hours reperfusion. Although anti-VCAM-1 attenuated neutrophil emigration by 90% in CD18-null mice, it did not diminish myocardial injury. To determine if CD18-independent neutrophil emigration was a tissue-specific response, we used isolated peripheral blood neutrophils from wild-type or CD18-null mice and showed neutrophil migration across lipopolysaccharide-activated cultured cardiac endothelium is CD18-independent, whereas migration across endothelium obtained from inferior vena cava is CD18-dependent. Consistent with our in vivo findings, migration of CD18-deficient neutrophils on cardiac endothelial monolayers is blocked by antibodies against alpha4 integrin or VCAM-1. We conclude tissue-specific differences in endothelial cells account, at least partially, for CD18-independent neutrophil infiltration in the heart.
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PMID:Role of alpha4 integrin and VCAM-1 in CD18-independent neutrophil migration across mouse cardiac endothelium. 1190 20

This study was designed to investigate the effects of various chemically distinct activators of PPAR-gamma and PPAR-alpha in a rat model of acute myocardial infarction. Using Northern blot analysis and RT-PCR in samples of rat heart, we document the expression of the mRNA for PPAR-gamma (isoform 1 but not isoform 2) as well as PPAR-beta and PPAR-alpha in freshly isolated cardiac myocytes and cardiac fibroblasts and in the left and right ventricles of the heart. Using a rat model of regional myocardial ischemia and reperfusion (in vivo), we have discovered that various chemically distinct ligands of PPAR-gamma (including the TZDs rosiglitazone, ciglitazone, and pioglitazone, as well as the cyclopentanone prostaglandins 15D-PGJ2 and PGA1) cause a substantial reduction of myocardial infarct size in the rat. We demonstrate that two distinct ligands of PPAR-alpha (including clofibrate and WY 14643) also cause a substantial reduction of myocardial infarct size in the rat. The most pronounced reduction in infarct size was observed with the endogenous PPAR-gamma ligand, 15-deoxyDelta12,14-prostagalndin J2 (15D-PGJ2). The mechanisms of the cardioprotective effects of 15D-PGJ2 may include 1) activation of PPAR-alpha, 2) activation of PPAR-gamma, 3) expression of HO-1, and 4) inhibition of the activation of NF-kappaB in the ischemic-reperfused heart. Inhibition by 15D-PGJ2 of the activation of NF-kappaB in turn results in a reduction of the 1) expression of inducible nitric oxide synthase and the nitration of proteins by peroxynitrite, 2) formation of the chemokine MCP-1, and 3) expression of the adhesion molecule ICAM-1. We speculate that ligands of PPAR-gamma and PPAR-alpha may be useful in the therapy of conditions associated with ischemia-reperfusion of the heart and other organs. Our findings also imply that TZDs and fibrates may help protect the heart against ischemia-reperfusion injury. This beneficial effect of 15D-PGJ2 was associated with a reduction in the expression of the 1) adhesion molecules ICAM-1 and P-selectin, 2) chemokine macrophage chemotactic protein 1, and 3) inducible isoform of nitric oxide synthase. 15D-PGJ2 reduced the nitration of proteins (immunohistological analysis of nitrotyrosine formation) caused by ischemia-reperfusion, likely due to the generation of peroxynitrite. Not all of the effects of 15D-PGJ2, however, are due to the activation of PPAR-gamma. For instance, exposure of rat cardiac myocytes to 15D-PGJ2, but not to rosiglitazone, results in an up-regulation of the expression of the mRNA for heme-oxygenase-1 (HO-1). Taken together, these results provide convincing evidence that several, chemically distinct ligands of PPAR-gamma reduce the tissue necrosis associated with acute myocardial infarction.
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PMID:Ligands of the peroxisome proliferator-activated receptors (PPAR-gamma and PPAR-alpha) reduce myocardial infarct size. 1208 64

1. Myocardial injury caused by ischaemia and reperfusion comes from multiple pathogenic events, including endothelial damage, neutrophil extravasation into tissue, mast cell activation, and peroxidation of cell membrane lipids. These events are followed by myocardial cell alterations resulting eventually in cell necrosis. An enhanced formation of reactive oxygen species is widely accepted as a stimulus for tissue destruction and cardiac failure. 2. In this study, we have investigated the cardioprotective effects of M40403 in myocardial ischaemia-reperfusion injury. M40403 is a low molecular weight, synthetic manganese containing superoxide dismutase mimetic (SODm) that selectively removes superoxide anion. Ischaemia was induced in rat hearts in vivo by ligating the left anterior descending coronary artery. Thirty minutes after the induction of ischaemia, the ligature was removed and reperfusion allowed to occur for at least 60 min. M40403 (0.1-1 mg kg(-1)) was given intravenously 15 min before ischaemia. 3. The results obtained in this study showed that M40403 significantly reduced the extent of myocardial damage, mast cell degranulation and the incidence of ventricular arrhythmias. Furthermore, M40403 significantly attenuated, in a dose-dependent manner, neutrophil infiltration in the myocardium as well as the associated induction of lipid peroxidation. Calcium overload seen post-reperfusion of the ischaemic myocardium was also reduced by M40403. 4. Immunohistochemical analysis for nitrotyrosine revealed a positive staining in cardiac tissue taken after reperfusion: this was attenuated by M40403. Moreover reperfused cardiac tissue sections showed positive staining for P-selectin and for anti-intercellular adhesion molecule (ICAM-1) in the vascular endothelial cells. M40403 treatment markedly reduced the intensity and degree of P-selectin and ICAM-1 in these tissues. No staining for nitrotyrosine, P-selectin or ICAM-1 was found in cardiac tissue taken at the end of the ischaemic period. 5. Overall, M40403 treatment reduced the morphological signs of myocardial cell injury and significantly improved survival. 6. Taken together, these results clearly indicate that M40403 treatment exerts a protective effect against ischaemia-reperfusion-induced myocardial injury, supporting a key role for superoxide anion in reperfusion injuries. This suggests that synthetic enzymes of SOD such as M40403, offer a novel therapeutic approach for the treatment of ischaemic heart disease where superoxide anion plays a dominant role.
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PMID:Protective effects of M40403, a selective superoxide dismutase mimetic, in myocardial ischaemia and reperfusion injury in vivo. 1211 Jun 15

A recently identified lectin-like oxidized low-density lipoprotein receptor (LOX-1) mediates endothelial cell injury and facilitates inflammatory cell adhesion. We studied the role of LOX-1 in myocardial ischemia-reperfusion (I/R) injury. Anesthetized Sprague-Dawley rats were subjected to 60 min of left coronary artery (LCA) ligation, followed by 60 min of reperfusion. Rats were treated with saline, LOX-1 blocking antibody JXT21 (10 mg/kg), or nonspecific anti-goat IgG (10 mg/kg) before I/R. Ten other rats underwent surgery without LCA ligation and served as a sham control group. LOX-1 expression was markedly increased during I/R (P < 0.01 vs. sham control group). Simultaneously, the expression of matrix metalloproteinase-1 (MMP-1) and adhesion molecules (P-selectin, VCAM-1, and ICAM-1) was also increased in the I/R area (P < 0.01 vs. sham control group). There was intense leukocyte accumulation in the I/R area in the saline-treated group. Treatment of rats with the LOX-1 antibody prevented I/R-induced upregulation of LOX-1 and reduced MMP-1 and adhesion molecule expression as well as leukocyte recruitment. LOX-1 antibody, but not nonspecific IgG, also reduced myocardial infarct size (P < 0.01 vs. saline-treated I/R group). To explore the link between LOX-1 and adhesion molecule expression, we measured expression of oxidative stress-sensitive p38 mitogen-activated protein kinase (p38 MAPK). The activity of p38 MAPK was increased during I/R (P < 0.01 vs. sham control), and use of LOX-1 antibody inhibited p38 MAPK activation (P < 0.01). These findings indicate that myocardial I/R upregulates LOX-1 expression, which through p38 MAPK activation increases the expression of MMP-1 and adhesion molecules. Inhibition of LOX-1 exerts an important protective effect against myocardial I/R injury.
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PMID:LOX-1 inhibition in myocardial ischemia-reperfusion injury: modulation of MMP-1 and inflammation. 1238 56


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