56 results on '"Lepore JJ"'
Search Results
2. Inhibition of p38 mitogen-activated protein kinase improves nitric oxide-mediated vasodilatation and reduces inflammation in hypercholesterolemia.
- Author
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Cheriyan J, Webb AJ, Sarov-Blat L, Elkhawad M, Wallace SM, Mäki-Petäjä KM, Collier DJ, Morgan J, Fang Z, Willette RN, Lepore JJ, Cockcroft JR, Sprecher DL, Wilkinson IB, Cheriyan, Joseph, Webb, Andrew J, Sarov-Blat, Lea, Elkhawad, Maysoon, Wallace, Sharon M L, and Mäki-Petäjä, Kaisa M
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- 2011
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3. Sildenafil improves exercise hemodynamics and oxygen uptake in patients with systolic heart failure.
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Lewis GD, Lachmann J, Camuso J, Lepore JJ, Shin J, Martinovic ME, Systrom DM, Bloch KD, and Semigran MJ
- Published
- 2007
4. Hemodynamic effects of sildenafil in patients with congestive heart failure and pulmonary hypertension: combined administration with inhaled nitric oxide.
- Author
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Lepore JJ, Maroo A, Bigatello LM, Dec GW, Zapol WM, Bloch KD, and Semigran MJ
- Abstract
Study objectives: In patients with pulmonary hypertension (PH) secondary to congestive heart failure, inhaled nitric oxide (NO) increases pulmonary vascular smooth-muscle intracellular cyclic guanosine monophosphate (cGMP) concentration, thereby decreasing pulmonary vascular resistance (PVR) and increasing cardiac index (CI). However, these beneficial effects of inhaled NO are limited in magnitude and duration, at least in part due to cGMP hydrolysis by the type 5 isoform of phosphodiesterase (PDE5). The goal of this study was to determine the acute pulmonary and systemic hemodynamic effects of the selective PDE5 inhibitor, sildenafil, administered alone or in combination with inhaled NO in patients with congestive heart failure and PH.Design: Single center, case series, pharmacohemodynamic study.Setting: Cardiac catheterization laboratory of a tertiary care academic teaching hospital.Patients: We studied 11 patients with left ventricular systolic dysfunction due to coronary artery disease or idiopathic dilated cardiomyopathy who had PH.Interventions: We administered oral sildenafil (50 mg), inhaled NO (80 ppm), and the combination of sildenafil and inhaled NO during right-heart and micromanometer left-heart catheterization.Measurements and results: Sildenafil administered alone decreased mean pulmonary artery pressure by 12 +/- 5%, PVR by 12 +/- 5%, systemic vascular resistance (SVR) by 13 +/- 6%, and pulmonary capillary wedge pressure by 12 +/- 7%, and increased CI by 14 +/- 5% (all p < 0.05) [+/- SEM]. The combination of inhaled NO and sildenafil decreased PVR by 50 +/- 4%, decreased SVR by 24 +/- 3%, and increased CI by 30 +/- 4% (all p < 0.01). These effects were greater than those observed with either agent alone (p < 0.05). In addition, sildenafil prolonged the pulmonary vasodilator effect of inhaled NO. Administration of sildenafil alone or in combination with inhaled NO did not change systemic arterial pressure or indexes of myocardial systolic or diastolic function.Conclusions: PDE5 inhibition with sildenafil improves cardiac output by balanced pulmonary and systemic vasodilation, and augments and prolongs the hemodynamic effects of inhaled NO in patients with chronic congestive heart failure and PH. [ABSTRACT FROM AUTHOR]
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- 2005
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5. Detection of cardiac allograft rejection and response to immunosuppressive therapy with peripheral blood gene expression.
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Horwitz PA, Tsai EJ, Putt ME, Gilmore JM, Lepore JJ, Parmacek MS, Kao AC, Desai SS, Goldberg LR, Brozena SC, Jessup ML, Epstein JA, and Cappola TP
- Published
- 2004
6. A Randomized, Placebo-Controlled Trial to Assess the Effects of 8 Weeks of Administration of GSK256073, a Selective GPR109A Agonist, on High-Density Lipoprotein Cholesterol in Subjects With Dyslipidemia.
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Olson EJ, Mahar KM, Haws TF, Fossler MJ, Gao F, de Gouville AC, Sprecher DL, and Lepore JJ
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- Aged, Drug Administration Routes, Dyslipidemias metabolism, Female, Humans, Male, Middle Aged, Niacin adverse effects, Receptors, G-Protein-Coupled agonists, Treatment Outcome, Xanthines adverse effects, Xanthines pharmacology, Cholesterol, HDL analysis, Dyslipidemias drug therapy, Flushing chemically induced, Xanthines administration & dosage
- Abstract
GPR109A (HM74A), a G-protein-coupled receptor, is hypothesized to mediate lipid and lipoprotein changes and dermal flushing associated with niacin administration. GSK256073 (8-chloro-3-pentyl-1H-purine-2,6[3H,7H]-dione) is a selective GPR109A agonist shown to suppress fatty acid levels and produce mild flushing in short-term clinical studies. This study evaluated the effects of GSK256073 on lipids in subjects with low high-density lipoprotein cholesterol (HDLc). Subjects (n = 80) were randomized (1:1:1:1) to receive GSK256073 5, 50, or 150 mg/day or matching placebo for 8 weeks. The primary end point was determining the GSK256073 exposure-response relationship for change from baseline in HDLc. No significant exposure response was observed between GSK256073 and HDLc levels. GSK256073 did not significantly alter HDLc levels versus placebo, but rather revealed a trend at the 150-mg dose for a nonsignificant decrease in HDLc (-6.31%; P = .12) and an increase in triglycerides (median, 24.4%; 95% confidence interval, 7.3%-41.6%). Flushing was reported in 21%, 25%, and 60% of subjects (5, 50, and 150 mg, respectively) versus 24% for placebo. Results indicated that selective activation of the GPR109A receptor with GSK256073 did not produce niacin-like lipid effects. These findings add to the increasing evidence that niacin-mediated lipoprotein changes occur predominantly via GPR109A-independent pathways., (© 2019, The American College of Clinical Pharmacology.)
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- 2019
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7. Daprodustat for anemia: a 24-week, open-label, randomized controlled trial in participants on hemodialysis.
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Meadowcroft AM, Cizman B, Holdstock L, Biswas N, Johnson BM, Jones D, Nossuli AK, Lepore JJ, Aarup M, and Cobitz AR
- Abstract
Background: This study evaluated the hemoglobin dose response, other efficacy measures and safety of daprodustat, an orally administered, hypoxia-inducible factor prolyl hydroxylase inhibitor in development for anemia of chronic kidney disease., Methods: Participants ( n = 216) with baseline hemoglobin levels of 9-11.5 g/dL on hemodialysis (HD) previously receiving stable doses of recombinant human erythropoietin (rhEPO) were randomized in a 24-week dose-range, efficacy and safety study. Participants discontinued rhEPO and then were randomized to receive daily daprodustat (4, 6, 8, 10 or 12 mg) or control (placebo for 4 weeks then open-label rhEPO as required). After 4 weeks, doses were titrated to achieve a hemoglobin target of 10-11.5 g/dL. The primary outcome was characterization of the dose-response relationship between daprodustat and hemoglobin at 4 weeks; additionally, the efficacy and safety of daprodustat were assessed over 24 weeks., Results: Over the first 4 weeks, the mean hemoglobin change from baseline increased dose-dependently from -0.29 (daprodustat 4 mg) to 0.69 g/dL (daprodustat 10 and 12 mg). The mean change from baseline hemoglobin (10.4 g/dL) at 24 weeks was 0.03 and -0.11 g/dL for the combined daprodustat and control groups, respectively. The median maximum observed plasma EPO levels in the control group were ∼14-fold higher than in the combined daprodustat group. Daprodustat demonstrated an adverse event profile consistent with the HD population., Conclusions: Daprodustat produced dose-dependent changes in hemoglobin over the first 4 weeks after switching from a stable dose of rhEPO as well as maintained hemoglobin target levels over 24 weeks.
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- 2019
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8. Daprodustat for anemia: a 24-week, open-label, randomized controlled trial in participants with chronic kidney disease.
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Holdstock L, Cizman B, Meadowcroft AM, Biswas N, Johnson BM, Jones D, Kim SG, Zeig S, Lepore JJ, and Cobitz AR
- Abstract
Background: This study assessed the short-term safety and efficacy of daprodustat (an oral hypoxia-inducible factor-prolyl hydroxylase inhibitor) to achieve a target hemoglobin in patients with anemia of chronic kidney disease (CKD)., Methods: Patients ( n = 252) with Stages 3-5 CKD not receiving dialysis were enrolled in this 24-week, multicenter trial [hemoglobin entry criteria: 8-10 g/dL (Cohort 1) or 8-11 g/dL (Cohort 2) for recombinant human erythropoietin (rhEPO)-naïve participants; 9-10.5 g/dL (Cohort 1) or 9-11.5 g/dL (Cohort 2) for rhEPO users]. rhEPO-naïve participants were randomized 3:1 to daprodustat (1, 2 or 4 mg) or control (rhEPO per standard of care). rhEPO users were randomized 1:1 to daprodustat 2 mg or control. Study medication was titrated to maintain hemoglobin 9-10.5 g/dL (Cohort 1) or 10-11.5 g/dL (Cohort 2). Hemoglobin, iron metabolism markers and safety parameters were measured every 4 weeks., Results: Mean hemoglobin levels at Week 24 were 10.2 g/dL (Cohort 1) and 10.9 g/dL (Cohort 2) in the daprodustat group and 10.7 g/dL (Cohort 1) and 11.0 g/dL (Cohort 2) in the control group. Participants had hemoglobin levels within the target range a median of 82% and 66% of the time between Weeks 12 and 24 in the daprodustat and control groups, respectively. The adverse event profile was consistent with clinical events in the CKD population., Conclusions: Daprodustat effectively maintained target hemoglobin over 24 weeks in CKD patients with anemia who were rhEPO naïve or had switched from existing rhEPO therapy.
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- 2019
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9. Effects of the Novel Long-Acting GLP-1 Agonist, Albiglutide, on Cardiac Function, Cardiac Metabolism, and Exercise Capacity in Patients With Chronic Heart Failure and Reduced Ejection Fraction.
- Author
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Lepore JJ, Olson E, Demopoulos L, Haws T, Fang Z, Barbour AM, Fossler M, Davila-Roman VG, Russell SD, and Gropler RJ
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- Adult, Aged, Carbon Radioisotopes, Chronic Disease, Echocardiography, Female, Fluorodeoxyglucose F18, Glucagon-Like Peptide 1 therapeutic use, Glucose metabolism, Heart Failure diagnostic imaging, Heart Failure metabolism, Heart Failure physiopathology, Humans, Male, Middle Aged, Myocardium metabolism, Oxygen Consumption, Positron Emission Tomography Computed Tomography, Quality of Life, Radiopharmaceuticals, Walk Test, Exercise Tolerance, Glucagon-Like Peptide 1 analogs & derivatives, Heart Failure drug therapy, Incretins therapeutic use, Stroke Volume
- Abstract
Objectives: This study sought to determine if glucagon-like peptide (GLP)-1 ameliorates myocardial metabolic abnormalities in chronic heart failure., Background: Albiglutide (GSK716155) is a GLP-1 agonist indicated for type 2 diabetes., Methods: We performed a randomized, placebo-controlled study evaluating 12 weeks of albiglutide in New York Heart Association II or III subjects with ejection fraction <40%. Subjects received weekly placebo (n = 30) or albiglutide 3.75 mg (n = 12), 15 mg (n = 13), or 30 mg (n = 27). The primary comparison was between albiglutide 30 mg and placebo. Assessments included echocardiography, 6-minute-walk test, and peak oxygen consumption. In a subgroup of patients, myocardial glucose and oxygen use were assessed. Endpoints are reported as change from baseline ± SE., Results: Albiglutide 30 mg compared with placebo did not improve change from baseline in left ventricular ejection fraction (2.4% [1.1%] vs. 4.4% [1.1%]; p = 0.22), 6-min walk test (18 [12] m vs. 9 [11] m; p = 0.58), myocardial glucose use (p = 0.59), or oxygen use (p = 0.25). In contrast, albiglutide 30 mg versus placebo improved change from baseline in peak oxygen consumption (0.9 [0.5] ml/kg/min vs. -0.6 [0.5] ml/kg/min; p = 0.02). Albiglutide was well tolerated., Conclusions: Although there was no detectable effect of albiglutide on cardiac function or myocardial glucose use, there was a modest increase in peak oxygen consumption, which could have been mediated by noncardiac effects. (A Multi-center, Placebo-controlled Study to Evaluate the Safety of GSK716155 and Its Effects on Myocardial Metabolism, Myocardial Function, and Exercise Capacity in Patients With NYHA Class II/III Congestive Heart Failure; NCT01357850)., (Copyright © 2016 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.)
- Published
- 2016
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10. Effect of Losmapimod on Cardiovascular Outcomes in Patients Hospitalized With Acute Myocardial Infarction: A Randomized Clinical Trial.
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O'Donoghue ML, Glaser R, Cavender MA, Aylward PE, Bonaca MP, Budaj A, Davies RY, Dellborg M, Fox KA, Gutierrez JA, Hamm C, Kiss RG, Kovar F, Kuder JF, Im KA, Lepore JJ, Lopez-Sendon JL, Ophuis TO, Parkhomenko A, Shannon JB, Spinar J, Tanguay JF, Ruda M, Steg PG, Theroux P, Wiviott SD, Laws I, Sabatine MS, and Morrow DA
- Subjects
- Aged, Algorithms, C-Reactive Protein analysis, Cyclopropanes adverse effects, Double-Blind Method, Drug Administration Schedule, Female, Hospitalization, Humans, Male, Middle Aged, Myocardial Infarction enzymology, Myocardial Infarction mortality, Myocardial Ischemia prevention & control, Myocardial Ischemia surgery, Myocardial Revascularization, Protein Kinase Inhibitors adverse effects, Pyridines adverse effects, Recurrence, Secondary Prevention, Treatment Failure, Cyclopropanes therapeutic use, Myocardial Infarction drug therapy, Protein Kinase Inhibitors therapeutic use, Pyridines therapeutic use, p38 Mitogen-Activated Protein Kinases antagonists & inhibitors
- Abstract
Importance: p38 Mitogen-activated protein kinase (MAPK)-stimulated inflammation is implicated in atherogenesis, plaque destabilization, and maladaptive processes in myocardial infarction (MI). Pilot data in a phase 2 trial in non-ST elevation MI indicated that the p38 MAPK inhibitor losmapimod attenuates inflammation and may improve outcomes., Objective: To evaluate the efficacy and safety of losmapimod on cardiovascular outcomes in patients hospitalized with an acute myocardial infarction., Design, Setting, and Patients: LATITUDE-TIMI 60, a randomized, placebo-controlled, double-blind, parallel-group trial conducted at 322 sites in 34 countries from June 3, 2014, until December 8, 2015. Part A consisted of a leading cohort (n = 3503) to provide an initial assessment of safety and exploratory efficacy before considering progression to part B (approximately 22,000 patients). Patients were considered potentially eligible for enrollment if they had been hospitalized with an acute MI and had at least 1 additional predictor of cardiovascular risk., Interventions: Patients were randomized to either twice-daily losmapimod (7.5 mg; n = 1738) or matching placebo (n = 1765) on a background of guideline-recommended therapy. Patients were treated for 12 weeks and followed up for an additional 12 weeks., Main Outcomes and Measures: The primary end point was the composite of cardiovascular death, MI, or severe recurrent ischemia requiring urgent coronary revascularization with the principal analysis specified at week 12., Results: In part A, among the 3503 patients randomized (median age, 66 years; 1036 [29.6%] were women), 99.1% had complete ascertainment for the primary outcome. The primary end point occurred by 12 weeks in 123 patients treated with placebo (7.0%) and 139 patients treated with losmapimod (8.1%; hazard ratio, 1.16; 95% CI, 0.91-1.47; P = .24). The on-treatment rates of serious adverse events were 16.0% with losmapimod and 14.2% with placebo., Conclusions and Relevance: Among patients with acute MI, use of losmapimod compared with placebo did not reduce the risk of major ischemic cardiovascular events. The results of this exploratory efficacy study did not justify proceeding to a larger efficacy trial in the existing patient population., Trial Registration: clinicaltrials.gov Identifier: NCT02145468.
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- 2016
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11. Four-Week Studies of Oral Hypoxia-Inducible Factor-Prolyl Hydroxylase Inhibitor GSK1278863 for Treatment of Anemia.
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Holdstock L, Meadowcroft AM, Maier R, Johnson BM, Jones D, Rastogi A, Zeig S, Lepore JJ, and Cobitz AR
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- Aged, Anemia blood, Anemia etiology, Erythropoietin therapeutic use, Female, Glycine therapeutic use, Hemoglobins analysis, Humans, Hypoxia-Inducible Factor-Proline Dioxygenases antagonists & inhibitors, Male, Middle Aged, Renal Dialysis, Renal Insufficiency, Chronic blood, Renal Insufficiency, Chronic complications, Renal Insufficiency, Chronic therapy, Single-Blind Method, Time Factors, Anemia drug therapy, Barbiturates therapeutic use, Glycine analogs & derivatives
- Abstract
Hypoxia-inducible factor prolyl hydroxylase inhibitors stabilize levels of hypoxia-inducible factor that upregulate transcription of multiple genes associated with the response to hypoxia, including production of erythropoietin. We conducted two phase 2a studies to explore the relationship between the dose of the hypoxia-inducible factor-prolyl hydroxylase inhibitor GSK1278863 and hemoglobin response in patients with anemia of CKD (baseline hemoglobin 8.5-11.0 g/dl) not undergoing dialysis and not receiving recombinant human erythropoietin (nondialysis study) and in patients with anemia of CKD (baseline hemoglobin 9.5-12.0 g/dl) on hemodialysis and being treated with stable doses of recombinant human erythropoietin (hemodialysis study). Participants were randomized 1:1:1:1 to a once-daily oral dose of GSK1278863 (0.5 mg, 2 mg, or 5 mg) or control (placebo for the nondialysis study; continuing on recombinant human erythropoietin for the hemodialysis study) for 4 weeks, with a 2-week follow-up. In the nondialysis study, GSK1278863 produced dose-dependent effects on hemoglobin, with the highest dose resulting in a mean increase of 1 g/dl at week 4. In the hemodialysis study, treatment with GSK1278863 in the 5-mg arm maintained mean hemoglobin concentrations after the switch from recombinant human erythropoietin, whereas mean hemoglobin decreased in the lower-dose arms. In both studies, the effects on hemoglobin occurred with elevations in endogenous erythropoietin within the range usually observed in the respective populations and markedly lower than those in the recombinant human erythropoietin control arm in the hemodialysis study, and without clinically significant elevations in plasma vascular endothelial growth factor concentrations. GSK1278863 was generally safe and well tolerated at the doses and duration studied. GSK1278863 may prove an effective alternative for managing anemia of CKD., (Copyright © 2016 by the American Society of Nephrology.)
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- 2016
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12. Cardioprotection Resulting from Glucagon-Like Peptide-1 Administration Involves Shifting Metabolic Substrate Utilization to Increase Energy Efficiency in the Rat Heart.
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Aravindhan K, Bao W, Harpel MR, Willette RN, Lepore JJ, and Jucker BM
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- Animals, Carbon Isotopes metabolism, Cardiotonic Agents administration & dosage, Cyclic AMP metabolism, Energy Metabolism physiology, Fatty Acids metabolism, Glucagon-Like Peptide 1 administration & dosage, Glucose metabolism, Hydrogen-Ion Concentration, Magnetic Resonance Spectroscopy, Myocytes, Cardiac metabolism, Oxygen Consumption physiology, Rats, Cardiotonic Agents pharmacology, Energy Metabolism drug effects, Glucagon-Like Peptide 1 pharmacology, Myocardium metabolism, Reperfusion Injury metabolism
- Abstract
Previous studies have shown that glucagon-like peptide-1 (GLP-1) provides cardiovascular benefits independent of its role on peripheral glycemic control. However, the precise mechanism(s) by which GLP-1 treatment renders cardioprotection during myocardial ischemia remain unresolved. Here we examined the role for GLP-1 treatment on glucose and fatty acid metabolism in normal and ischemic rat hearts following a 30 min ischemia and 24 h reperfusion injury, and in isolated cardiomyocytes (CM). Relative carbohydrate and fat oxidation levels were measured in both normal and ischemic hearts using a 1-13C glucose clamp coupled with NMR-based isotopomer analysis, as well as in adult rat CMs by monitoring pH and O2 consumption in the presence of glucose or palmitate. In normal heart, GLP-1 increased glucose uptake (↑64%, p<0.05) without affecting glycogen levels. In ischemic hearts, GLP-1 induced metabolic substrate switching by increasing the ratio of carbohydrate versus fat oxidation (↑14%, p<0.01) in the LV area not at risk, without affecting cAMP levels. Interestingly, no substrate switching occurred in the LV area at risk, despite an increase in cAMP (↑106%, p<0.05) and lactate (↑121%, p<0.01) levels. Furthermore, in isolated CMs GLP-1 treatment increased glucose utilization (↑14%, p<0.05) and decreased fatty acid oxidation (↓15%, p<0.05) consistent with in vivo finding. Our results show that this benefit may derive from distinct and complementary roles of GLP-1 treatment on metabolism in myocardial sub-regions in response to this injury. In particular, a switch to anaerobic glycolysis in the ischemic area provides a compensatory substrate switch to overcome the energetic deficit in this region in the face of reduced tissue oxygenation, whereas a switch to more energetically favorable carbohydrate oxidation in more highly oxygenated remote regions supports maintaining cardiac contractility in a complementary manner.
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- 2015
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13. Losmapimod, a novel p38 mitogen-activated protein kinase inhibitor, in non-ST-segment elevation myocardial infarction: a randomised phase 2 trial.
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Newby LK, Marber MS, Melloni C, Sarov-Blat L, Aberle LH, Aylward PE, Cai G, de Winter RJ, Hamm CW, Heitner JF, Kim R, Lerman A, Patel MR, Tanguay JF, Lepore JJ, Al-Khalidi HR, Sprecher DL, and Granger CB
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- Aged, Area Under Curve, Double-Blind Method, Drug Administration Schedule, Female, Humans, Kaplan-Meier Estimate, Magnetic Resonance Angiography, Male, Middle Aged, Myocardial Infarction mortality, Treatment Outcome, Cyclopropanes administration & dosage, Myocardial Infarction drug therapy, Protein Kinase Inhibitors administration & dosage, Pyridines administration & dosage, p38 Mitogen-Activated Protein Kinases antagonists & inhibitors
- Abstract
Background: p38 MAPK inhibition has potential myocardial protective effects. We assessed losmapimod, a potent oral p38 MAPK inhibitor, in patients with non-ST-segment elevation myocardial infarction (NSTEMI) in a double-blind, randomised, placebo-controlled trial., Methods: From October, 2009, to November, 2011, NSTEMI patients were assigned oral losmapimod (7·5 mg or 15·0 mg loading dose followed by 7·5 mg twice daily) or matching placebo in a 3:3:2 ratio. Safety outcomes were serious adverse events and alanine aminotransferase (ALT) concentrations over 12 weeks, and cardiac events (death, myocardial infarction, recurrent ischaemia, stroke, and heart failure) at 90 days. Efficacy outcomes were high-sensitivity C-reactive protein (hsCRP) and B-type natriuretic peptide (BNP) concentrations at 72 h and 12 weeks, and troponin I area under the curve (AUC) over 72 h. The losmapimod groups were pooled for analysis. This trial is registered with ClinicalTrials.gov, number NCT00910962., Findings: Of 535 patients enrolled, 526 (98%) received at least one dose of study treatment (losmapimod n=388 and placebo n=138). Safety outcomes did not differ between groups. HsCRP concentrations at 72 h were lower in the losmapimod group than in the placebo group (geometric mean 64·1 nmol/L, 95% CI 53·0-77·6 vs 110·8 nmol/L, 83·1-147·7; p=0·0009) but were similar at 12 weeks. Early geometric mean BNP concentrations were similar at 72 h but significantly lower in the losmapimod group at 12 weeks (37·2 ng/L, 95% CI 32·3-42·9 vs 49·4 ng/L, 38·7-63·0; p=0·04). Mean troponin I AUC values did not differ., Interpretation: p38 MAPK inhibition with oral losmapimod was well tolerated in NSTEMI patients and might improve outcomes after acute coronary syndromes., Funding: GlaxoSmithKline., (Copyright © 2014 Elsevier Ltd. All rights reserved.)
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- 2014
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14. Combined TRPC3 and TRPC6 blockade by selective small-molecule or genetic deletion inhibits pathological cardiac hypertrophy.
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Seo K, Rainer PP, Shalkey Hahn V, Lee DI, Jo SH, Andersen A, Liu T, Xu X, Willette RN, Lepore JJ, Marino JP Jr, Birnbaumer L, Schnackenberg CG, and Kass DA
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- Animals, HEK293 Cells, Humans, Mice, Mice, Inbred C57BL, Mice, Knockout, Phosphorylation, Rats, TRPC Cation Channels genetics, TRPC6 Cation Channel, Cardiomegaly genetics, TRPC Cation Channels antagonists & inhibitors
- Abstract
Chronic neurohormonal and mechanical stresses are central features of heart disease. Increasing evidence supports a role for the transient receptor potential canonical channels TRPC3 and TRPC6 in this pathophysiology. Channel expression for both is normally very low but is increased by cardiac disease, and genetic gain- or loss-of-function studies support contributions to hypertrophy and dysfunction. Selective small-molecule inhibitors remain scarce, and none target both channels, which may be useful given the high homology among them and evidence of redundant signaling. Here we tested selective TRPC3/6 antagonists (GSK2332255B and GSK2833503A; IC50, 3-21 nM against TRPC3 and TRPC6) and found dose-dependent blockade of cell hypertrophy signaling triggered by angiotensin II or endothelin-1 in HEK293T cells as well as in neonatal and adult cardiac myocytes. In vivo efficacy in mice and rats was greatly limited by rapid metabolism and high protein binding, although antifibrotic effects with pressure overload were observed. Intriguingly, although gene deletion of TRPC3 or TRPC6 alone did not protect against hypertrophy or dysfunction from pressure overload, combined deletion was protective, supporting the value of dual inhibition. Further development of this pharmaceutical class may yield a useful therapeutic agent for heart disease management., Competing Interests: X.X, R.N.W., J.J.L., J.P.M., and C.G.S. are employees of Glaxo Smith Kline and contributed substantial resources in developing the new TRPC3/6 channel blockers.
- Published
- 2014
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15. Platelet aggregation unchanged by lipoprotein-associated phospholipase A₂ inhibition: results from an in vitro study and two randomized phase I trials.
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Shaddinger BC, Xu Y, Roger JH, Macphee CH, Handel M, Baidoo CA, Magee M, Lepore JJ, and Sprecher DL
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- Acetamides pharmacology, Adult, Analysis of Variance, Cross-Over Studies, Dose-Response Relationship, Drug, Humans, Male, Models, Biological, New South Wales, Phospholipase A2 Inhibitors metabolism, Platelet Aggregation physiology, Quinolones pharmacology, Lipoproteins metabolism, Phospholipase A2 Inhibitors pharmacology, Platelet Aggregation drug effects
- Abstract
Background: We explored the theorized upregulation of platelet-activating factor (PAF)- mediated biologic responses following lipoprotein-associated phospholipase A2 (Lp-PLA2) inhibition using human platelet aggregation studies in an in vitro experiment and in 2 clinical trials., Methods and Results: Full platelet aggregation concentration response curves were generated in vitro to several platelet agonists in human plasma samples pretreated with rilapladib (selective Lp-PLA2 inhibitor) or vehicle. This was followed by a randomized, double-blind crossover study in healthy adult men (n = 26) employing a single-agonist dose assay of platelet aggregation, after treatment of subjects with 250 mg oral rilapladib or placebo once daily for 14 days. This study was followed by a second randomized, double-blind parallel-group trial in healthy adult men (n = 58) also treated with 250 mg oral rilapladib or placebo once daily for 14 days using a full range of 10 collagen concentrations (0-10 µg/ml) for characterizing EC50 values for platelet aggregation for each subject. Both clinical studies were conducted at the GlaxoSmithKline Medicines Research Unit in the Prince of Wales Hospital, Sydney, Australia. EC50 values derived from multiple agonist concentrations were compared and no pro-aggregant signals were observed during exposure to rilapladib in any of these platelet studies, despite Lp-PLA2 inhibition exceeding 90%. An increase in collagen-mediated aggregation was observed 3 weeks post drug termination in the crossover study (15.4% vs baseline; 95% confidence interval [CI], 3.9-27.0), which was not observed during the treatment phase and was not observed in the parallel-group study employing a more robust EC50 examination., Conclusions: Lp-PLA2 inhibition does not enhance platelet aggregation., Trial Registration: 1) Study 1: ClinicalTrials.gov NCT01745458 2) Study 2: ClinicalTrials.gov NCT00387257.
- Published
- 2014
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16. Ephrin-B2 controls PDGFRβ internalization and signaling.
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Nakayama A, Nakayama M, Turner CJ, Höing S, Lepore JJ, and Adams RH
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- Animals, Cell Membrane metabolism, Cells, Cultured, Ephrin-B2 genetics, Female, Male, Mice, Mutation, Myocytes, Smooth Muscle pathology, Protein Transport, Ephrin-B2 metabolism, Receptor, Platelet-Derived Growth Factor beta metabolism, Signal Transduction
- Abstract
B-class ephrins, ligands for EphB receptor tyrosine kinases, are critical regulators of growth and patterning processes in many organs and species. In the endothelium of the developing vasculature, ephrin-B2 controls endothelial sprouting and proliferation, which has been linked to vascular endothelial growth factor (VEGF) receptor endocytosis and signaling. Ephrin-B2 also has essential roles in supporting mural cells (namely, pericytes and vascular smooth muscle cells [VSMCs]), but the underlying mechanism is not understood. Here, we show that ephrin-B2 controls platelet-derived growth factor receptor β (PDGFRβ) distribution in the VSMC plasma membrane, endocytosis, and signaling in a fashion that is highly distinct from its role in the endothelium. Absence of ephrin-B2 in cultured VSMCs led to the redistribution of PDGFRβ from caveolin-positive to clathrin-associated membrane fractions, enhanced PDGF-B-induced PDGFRβ internalization, and augmented downstream mitogen-activated protein (MAP) kinase and c-Jun N-terminal kinase (JNK) activation but impaired Tiam1-Rac1 signaling and proliferation. Accordingly, mutant mice lacking ephrin-B2 expression in vascular smooth muscle developed vessel wall defects and aortic aneurysms, which were associated with impaired Tiam1 expression and excessive activation of MAP kinase and JNK. Our results establish that ephrin-B2 is an important regulator of PDGFRβ endocytosis and thereby acts as a molecular switch controlling the downstream signaling activity of this receptor in mural cells.
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- 2013
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17. Inhibition of the cardiomyocyte-specific kinase TNNI3K limits oxidative stress, injury, and adverse remodeling in the ischemic heart.
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Vagnozzi RJ, Gatto GJ Jr, Kallander LS, Hoffman NE, Mallilankaraman K, Ballard VL, Lawhorn BG, Stoy P, Philp J, Graves AP, Naito Y, Lepore JJ, Gao E, Madesh M, and Force T
- Subjects
- Acute Coronary Syndrome complications, Acute Coronary Syndrome enzymology, Acute Coronary Syndrome pathology, Acute Coronary Syndrome physiopathology, Animals, Cell Death drug effects, Disease Models, Animal, Energy Metabolism drug effects, Enzyme Activation drug effects, Gene Deletion, Heart Failure complications, Heart Failure enzymology, Heart Failure physiopathology, Humans, MAP Kinase Kinase Kinases metabolism, Mice, Mice, Inbred C57BL, Mitochondria metabolism, Myocardial Ischemia complications, Myocardial Ischemia pathology, Myocardial Reperfusion Injury pathology, Myocytes, Cardiac enzymology, Myocytes, Cardiac pathology, Protein Kinase Inhibitors chemistry, Protein Kinase Inhibitors pharmacology, Protein Serine-Threonine Kinases, Small Molecule Libraries chemistry, Small Molecule Libraries pharmacology, Superoxides metabolism, Up-Regulation drug effects, Ventricular Dysfunction, Left complications, Ventricular Dysfunction, Left enzymology, Ventricular Dysfunction, Left pathology, Ventricular Dysfunction, Left physiopathology, p38 Mitogen-Activated Protein Kinases metabolism, MAP Kinase Kinase Kinases antagonists & inhibitors, Myocardial Ischemia enzymology, Myocardial Ischemia physiopathology, Oxidative Stress drug effects, Protein Kinases metabolism, Ventricular Remodeling drug effects
- Abstract
Percutaneous coronary intervention is first-line therapy for acute coronary syndromes (ACS) but can promote cardiomyocyte death and cardiac dysfunction via reperfusion injury, a phenomenon driven in large part by oxidative stress. Therapies to limit this progression have proven elusive, with no major classes of new agents since the development of anti-platelets/anti-thrombotics. We report that cardiac troponin I-interacting kinase (TNNI3K), a cardiomyocyte-specific kinase, promotes ischemia/reperfusion injury, oxidative stress, and myocyte death. TNNI3K-mediated injury occurs through increased mitochondrial superoxide production and impaired mitochondrial function and is largely dependent on p38 mitogen-activated protein kinase (MAPK) activation. We developed a series of small-molecule TNNI3K inhibitors that reduce mitochondrial-derived superoxide generation, p38 activation, and infarct size when delivered at reperfusion to mimic clinical intervention. TNNI3K inhibition also preserves cardiac function and limits chronic adverse remodeling. Our findings demonstrate that TNNI3K modulates reperfusion injury in the ischemic heart and is a tractable therapeutic target for ACS. Pharmacologic TNNI3K inhibition would be cardiac-selective, preventing potential adverse effects of systemic kinase inhibition.
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- 2013
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18. Novel fusion of GLP-1 with a domain antibody to serum albumin prolongs protection against myocardial ischemia/reperfusion injury in the rat.
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Bao W, Holt LJ, Prince RD, Jones GX, Aravindhan K, Szapacs M, Barbour AM, Jolivette LJ, Lepore JJ, Willette RN, DeAngelis E, and Jucker BM
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- Animals, Cardiotonic Agents administration & dosage, Cardiotonic Agents blood, Cardiotonic Agents pharmacokinetics, Disease Models, Animal, Exenatide, Glucagon-Like Peptide 1 administration & dosage, Glucagon-Like Peptide 1 blood, Glucagon-Like Peptide 1 pharmacokinetics, Glucagon-Like Peptide-1 Receptor, Immunoconjugates administration & dosage, Immunoconjugates blood, Immunoconjugates pharmacokinetics, Injections, Subcutaneous, Male, Myocardial Contraction drug effects, Myocardial Infarction metabolism, Myocardial Infarction pathology, Myocardial Infarction physiopathology, Myocardial Reperfusion Injury metabolism, Myocardial Reperfusion Injury pathology, Myocardial Reperfusion Injury physiopathology, Myocardium metabolism, Myocardium pathology, Peptide Fragments administration & dosage, Peptide Fragments blood, Peptide Fragments pharmacokinetics, Peptides pharmacology, Rats, Rats, Sprague-Dawley, Receptors, Glucagon agonists, Receptors, Glucagon genetics, Single-Domain Antibodies administration & dosage, Single-Domain Antibodies blood, Venoms pharmacology, Ventricular Function, Left drug effects, Cardiotonic Agents pharmacology, Glucagon-Like Peptide 1 pharmacology, Immunoconjugates pharmacology, Myocardial Infarction prevention & control, Myocardial Reperfusion Injury prevention & control, Peptide Fragments pharmacology, Serum Albumin immunology, Single-Domain Antibodies pharmacology
- Abstract
Background: Glucagon-like peptide-1 (GLP-1) and its mimetics reduce infarct size in the setting of acute myocardial ischemia/reperfusion (I/R) injury. However, the short serum half-life of GLP-1 and its mimetics may limit their therapeutic use in acute myocardial ischemia. Domain antibodies to serum albumin (AlbudAbs) have been developed to extend the serum half-life of short lived therapeutic proteins, peptides and small molecules. In this study, we compared the effect of a long acting GLP-1 agonist, DPP-IV resistant GLP-1 (7-36, A8G) fused to an AlbudAb (GAlbudAb), with the effect of the GLP-1 mimetic, exendin-4 (short half-life GLP-1 agonist) on infarct size following acute myocardial I/R injury., Methods: Male Sprague-Dawley rats (8-week-old) were treated with vehicle, GAlbudAb or exendin-4. Myocardial ischemia was induced 2 h following the final dose for GAlbudAb and 30 min post the final dose for exendin-4. In a subgroup of animals, the final dose of exendin-4 was administered (1 μg/kg, SC, bid for 2 days) 6 h prior to myocardial ischemia when plasma exendin-4 was at its minimum concentration (C(min)). Myocardial infarct size, area at risk and cardiac function were determined 24 h after myocardial I/R injury., Results: GAlbudAb and exendin-4 significantly reduced myocardial infarct size by 28% and 23% respectively, compared to vehicle (both p < 0.01 vs. vehicle) after I/R injury. Moreover, both GAlbudAb and exendin-4 markedly improved post-ischemic cardiac contractile function. Body weight loss and reduced food intake consistent with the activation of GLP-1 receptors was observed in all treatment groups. However, exendin-4 failed to reduce infarct size when administered 6 h prior to myocardial ischemia, suggesting continuous activation of the GLP-1 receptors is needed for cardioprotection., Conclusions: Cardioprotection provided by GAlbudAb, a long acting GLP-1 mimetic, following myocardial I/R injury was comparable in magnitude, but more sustained in duration than that produced by short-acting exendin-4. Very low plasma concentrations of exendin-4 failed to protect the heart from myocardial I/R injury, suggesting that sustained GLP-1 receptor activation plays an important role in providing cardioprotection in the setting of acute myocardial I/R injury. Long-acting GLP-1 agonists such as GAlbudAb may warrant additional evaluation as novel therapeutic agents to reduce myocardial I/R injury during acute coronary syndrome.
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- 2013
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19. Human-induced pluripotent stem cell-derived cardiomyocytes exhibit temporal changes in phenotype.
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Ivashchenko CY, Pipes GC, Lozinskaya IM, Lin Z, Xiaoping X, Needle S, Grygielko ET, Hu E, Toomey JR, Lepore JJ, and Willette RN
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- Cell Differentiation physiology, Cell Line, Humans, Ion Channels physiology, Myocytes, Cardiac classification, Phenotype, Pluripotent Stem Cells classification, Action Potentials physiology, Calcium Signaling physiology, Gene Expression Regulation, Developmental physiology, Myocytes, Cardiac cytology, Myocytes, Cardiac physiology, Pluripotent Stem Cells cytology, Pluripotent Stem Cells physiology
- Abstract
Human-induced pluripotent stem cell-derived cardiomyocytes (hiPS-CMs) have been recently derived and are used for basic research, cardiotoxicity assessment, and phenotypic screening. However, the hiPS-CM phenotype is dependent on their derivation, age, and culture conditions, and there is disagreement as to what constitutes a functional hiPS-CM. The aim of the present study is to characterize the temporal changes in hiPS-CM phenotype by examining five determinants of cardiomyocyte function: gene expression, ion channel functionality, calcium cycling, metabolic activity, and responsiveness to cardioactive compounds. Based on both gene expression and electrophysiological properties, at day 30 of differentiation, hiPS-CMs are immature cells that, with time in culture, progressively develop a more mature phenotype without signs of dedifferentiation. This phenotype is characterized by adult-like gene expression patterns, action potentials exhibiting ventricular atrial and nodal properties, coordinated calcium cycling and beating, suggesting the formation of a functional syncytium. Pharmacological responses to pathological (endothelin-1), physiological (IGF-1), and autonomic (isoproterenol) stimuli similar to those characteristic of isolated adult cardiac myocytes are present in maturing hiPS-CMs. In addition, thyroid hormone treatment of hiPS-CMs attenuated the fetal gene expression in favor of a more adult-like pattern. Overall, hiPS-CMs progressively acquire functionality when maintained in culture for a prolonged period of time. The description of this evolving phenotype helps to identify optimal use of hiPS-CMs for a range of research applications.
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- 2013
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20. An orally active TRPV4 channel blocker prevents and resolves pulmonary edema induced by heart failure.
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Thorneloe KS, Cheung M, Bao W, Alsaid H, Lenhard S, Jian MY, Costell M, Maniscalco-Hauk K, Krawiec JA, Olzinski A, Gordon E, Lozinskaya I, Elefante L, Qin P, Matasic DS, James C, Tunstead J, Donovan B, Kallal L, Waszkiewicz A, Vaidya K, Davenport EA, Larkin J, Burgert M, Casillas LN, Marquis RW, Ye G, Eidam HS, Goodman KB, Toomey JR, Roethke TJ, Jucker BM, Schnackenberg CG, Townsley MI, Lepore JJ, and Willette RN
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- Administration, Oral, Animals, Blood Pressure drug effects, Calcium metabolism, Disease Models, Animal, Diuretics pharmacology, Endothelium drug effects, Endothelium metabolism, Endothelium pathology, Heart Failure pathology, Heart Failure physiopathology, Heart Rate drug effects, Humans, In Vitro Techniques, Ion Channel Gating drug effects, Lung drug effects, Lung metabolism, Lung pathology, Membrane Transport Modulators chemistry, Membrane Transport Modulators pharmacology, Mice, Mice, Knockout, Permeability drug effects, Protein Transport drug effects, Pulmonary Edema etiology, Pulmonary Edema pathology, Rats, TRPV Cation Channels metabolism, Water-Electrolyte Balance drug effects, Heart Failure complications, Membrane Transport Modulators administration & dosage, Membrane Transport Modulators therapeutic use, Pulmonary Edema drug therapy, Pulmonary Edema prevention & control, TRPV Cation Channels antagonists & inhibitors
- Abstract
Pulmonary edema resulting from high pulmonary venous pressure (PVP) is a major cause of morbidity and mortality in heart failure (HF) patients, but current treatment options demonstrate substantial limitations. Recent evidence from rodent lungs suggests that PVP-induced edema is driven by activation of pulmonary capillary endothelial transient receptor potential vanilloid 4 (TRPV4) channels. To examine the therapeutic potential of this mechanism, we evaluated TRPV4 expression in human congestive HF lungs and developed small-molecule TRPV4 channel blockers for testing in animal models of HF. TRPV4 immunolabeling of human lung sections demonstrated expression of TRPV4 in the pulmonary vasculature that was enhanced in sections from HF patients compared to controls. GSK2193874 was identified as a selective, orally active TRPV4 blocker that inhibits Ca(2+) influx through recombinant TRPV4 channels and native endothelial TRPV4 currents. In isolated rodent and canine lungs, TRPV4 blockade prevented the increased vascular permeability and resultant pulmonary edema associated with elevated PVP. Furthermore, in both acute and chronic HF models, GSK2193874 pretreatment inhibited the formation of pulmonary edema and enhanced arterial oxygenation. Finally, GSK2193874 treatment resolved pulmonary edema already established by myocardial infarction in mice. These findings identify a crucial role for TRPV4 in the formation of HF-induced pulmonary edema and suggest that TRPV4 blockade is a potential therapeutic strategy for HF patients.
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- 2012
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21. Effects of p38 mitogen-activated protein kinase inhibition on vascular and systemic inflammation in patients with atherosclerosis.
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Elkhawad M, Rudd JH, Sarov-Blat L, Cai G, Wells R, Davies LC, Collier DJ, Marber MS, Choudhury RP, Fayad ZA, Tawakol A, Gleeson FV, Lepore JJ, Davis B, Willette RN, Wilkinson IB, Sprecher DL, and Cheriyan J
- Subjects
- Aged, Aortitis blood, Aortitis diagnostic imaging, Aortitis enzymology, Atherosclerosis blood, Atherosclerosis diagnostic imaging, Atherosclerosis enzymology, Carotid Artery Diseases blood, Carotid Artery Diseases diagnostic imaging, Carotid Artery Diseases enzymology, Double-Blind Method, Female, Fluorodeoxyglucose F18, Humans, Hydroxymethylglutaryl-CoA Reductase Inhibitors therapeutic use, Inflammation Mediators blood, Intra-Abdominal Fat diagnostic imaging, Intra-Abdominal Fat drug effects, Male, Middle Aged, Multimodal Imaging, Odds Ratio, Positron-Emission Tomography, Predictive Value of Tests, Radiopharmaceuticals, Subcutaneous Fat diagnostic imaging, Subcutaneous Fat drug effects, Time Factors, Tomography, X-Ray Computed, Treatment Outcome, United Kingdom, p38 Mitogen-Activated Protein Kinases metabolism, Anti-Inflammatory Agents therapeutic use, Aortitis drug therapy, Atherosclerosis drug therapy, Carotid Artery Diseases drug therapy, Cyclopropanes therapeutic use, Protein Kinase Inhibitors therapeutic use, Pyridines therapeutic use, p38 Mitogen-Activated Protein Kinases antagonists & inhibitors
- Abstract
Objectives: This study sought to determine the effects of a p38 mitogen-activated protein kinase inhibitor, losmapimod, on vascular inflammation, by (18)F-fluorodeoxyglucose (FDG) positron emission tomography/computed tomography imaging., Background: The p38 mitogen-activated protein kinase cascade plays an important role in the initiation and progression of inflammatory diseases, including atherosclerosis., Methods: Patients with atherosclerosis on stable statin therapy (n = 99) were randomized to receive losmapimod 7.5 mg once daily (lower dose [LD]), twice daily (higher dose [HD]) or placebo for 84 days. Vascular inflammation was assessed by FDG positron emission tomography/computed tomography imaging of the carotid arteries and aorta; analyses focused on the index vessel (the artery with the highest average maximum tissue-to-background ratio [TBR] at baseline). Serum inflammatory biomarkers and FDG uptake in visceral and subcutaneous fat were also measured., Results: The primary endpoint, change from baseline in average TBR across all segments in the index vessel, was not significantly different between HD and placebo (ΔTBR: -0.04 [95% confidence interval [CI]: -0.14 to +0.06], p = 0.452) or LD and placebo (ΔTBR: -0.02 [95% CI: -0.11 to +0.06], p = 0.579). However, there was a statistically significant reduction in average TBR in active segments (TBR ≥1.6) (HD vs. placebo: ΔTBR: -0.10 [95% CI: -0.19 to -0.02], p = 0.0125; LD vs. placebo: ΔTBR: -0.10 [95% CI: -0.18 to -0.02], p = 0.0194). The probability of a segment being active was also significantly reduced for HD when compared with placebo (OR: 0.57 [95% CI: 0.41 to 0.81], p = 0.002). Within the HD group, reductions were observed in placebo-corrected inflammatory biomarkers including high-sensitivity C-reactive protein (% reduction: -28% [95% CI: -46 to -5], p = 0.023) as well as FDG uptake in visceral fat (ΔSUV: -0.05 [95% CI: -0.09 to -0.01], p = 0.018), but not subcutaneous fat., Conclusions: Despite nonsignificant changes for the primary endpoint of average vessel TBR, HD losmapimod reduced vascular inflammation in the most inflamed regions, concurrent with a reduction in inflammatory biomarkers and FDG uptake in visceral fat. These results suggest a systemic anti-inflammatory effect. (A Study to Evaluate the Effects of 3 Months Dosing With GW856553, as Assessed FDG-PET/CT Imaging; NCT00633022)., (Copyright © 2012 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.)
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- 2012
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22. Comparison of soluble guanylate cyclase stimulators and activators in models of cardiovascular disease associated with oxidative stress.
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Costell MH, Ancellin N, Bernard RE, Zhao S, Upson JJ, Morgan LA, Maniscalco K, Olzinski AR, Ballard VL, Herry K, Grondin P, Dodic N, Mirguet O, Bouillot A, Gellibert F, Coatney RW, Lepore JJ, Jucker BM, Jolivette LJ, Willette RN, Schnackenberg CG, and Behm DJ
- Abstract
Soluble guanylate cyclase (sGC), the primary mediator of nitric oxide (NO) bioactivity, exists as reduced (NO-sensitive) and oxidized (NO-insensitive) forms. We tested the hypothesis that the cardiovascular protective effects of NO-insensitive sGC activation would be potentiated under conditions of oxidative stress compared to those of NO-sensitive sGC stimulation. The cardiovascular effects of the NO-insensitive sGC activator GSK2181236A [a low, non-depressor dose, and a high dose which lowered mean arterial pressure (MAP) by 5-10 mmHg] and those of equi-efficacious doses of the NO-sensitive sGC stimulator BAY 60-4552 were assessed in (1) Sprague Dawley rats during coronary artery ischemia/reperfusion (I/R) and (2) spontaneously hypertensive stroke prone rats (SHR-SP) on a high salt/fat diet (HSFD). In I/R, neither compound reduced infarct size 24 h after reperfusion. In SHR-SP, HSFD increased MAP, urine output, microalbuminuria, and mortality, caused left ventricular hypertrophy with preserved ejection fraction, and impaired endothelium-dependent vasorelaxation. The low dose of BAY 60-4552, but not that of GSK2181236A, decreased urine output, and improved survival. Conversely, the low dose of GSK2181236A, but not that of BAY 60-4552, attenuated the development of cardiac hypertrophy. The high doses of both compounds similarly attenuated cardiac hypertrophy and improved survival. In addition to these effects, the high dose of BAY 60-4552 reduced urine output and microalbuminuria and attenuated the increase in MAP to a greater extent than did GSK2181236A. Neither compound improved endothelium-dependent vasorelaxation. In SHR-SP isolated aorta, the vasodilatory responses to the NO-dependent compounds carbachol and sodium nitroprusside were attenuated by HSFD. In contrast, the vasodilatory responses to both GSK2181236A and BAY 60-4552 were unaltered by HSFD, indicating that reduced NO-bioavailability and not changes in the oxidative state of sGC is responsible for the vascular dysfunction. In summary, GSK2181236A and BAY 60-4552 provide partial benefit against hypertension-induced end-organ damage. The differential beneficial effects observed between these compounds could reflect tissue-specific changes in the oxidative state of sGC and might help direct the clinical development of these novel classes of therapeutic agents.
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- 2012
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23. Aortic aneurysm generation in mice with targeted deletion of integrin-linked kinase in vascular smooth muscle cells.
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Shen D, Li J, Lepore JJ, Anderson TJ, Sinha S, Lin AY, Cheng L, Cohen ED, Roberts JD Jr, Dedhar S, Parmacek MS, and Gerszten RE
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- Animals, Aortic Aneurysm pathology, Cells, Cultured, Female, Gene Targeting methods, Mice, Mice, 129 Strain, Mice, Inbred C57BL, Mice, Transgenic, Muscle, Smooth, Vascular cytology, Muscle, Smooth, Vascular embryology, Myocytes, Smooth Muscle cytology, Pregnancy, Aortic Aneurysm enzymology, Gene Deletion, Muscle, Smooth, Vascular metabolism, Myocytes, Smooth Muscle metabolism, Protein Serine-Threonine Kinases deficiency, Protein Serine-Threonine Kinases genetics
- Abstract
Rationale: Integrin-linked kinase (ILK) is located at focal adhesions and links the extracellular matrix (ECM) to the actin cytoskeleton via β1- and β3-integrins. ILK plays a role in the activation of kinases including protein kinase B/Akt and glycogen synthase kinase 3β and regulates cell proliferation, motility, and survival., Objective: To determine the function of ILK in vascular smooth muscle cells (SMCs) in vivo., Methods and Results: SM22Cre(+)Ilk(Fl/Fl) conditional mutant mice were generated in which the Ilk gene was selectively ablated in SMCs. SM22Cre(+)Ilk(Fl/Fl) conditional mutant mice survive to birth but die in the perinatal period exhibiting multiple vascular pathologies including aneurysmal dilatation of the aorta and patent ductus arteriosus (PDA). Defects in morphogenetic development of the aorta were observed as early as E12.5 in SM22Cre(+)Ilk(Fl/Fl) mutant embryos. By late gestation (E16.5 to 18.5), striking expansion of the thoracic aorta was observed in ILK mutant embryos. Histological analyses revealed that the structural organization of the arterial tunica media is severely disrupted with profound derangements in SMC morphology, cell-cell, and cell-matrix relationships, including disruption of the elastic lamellae. ILK deletion in primary aortic SMCs results in alterations of RhoA/cytoskeletal signaling transduced through aberrant localization of myocardin-related transcription factor (MRTF)-A repressing the transcription and expression of SMC genes, which are required for the maintenance of the contractile SMC phenotype., Conclusions: These data identify a molecular pathway linking ILK signaling to the contractile SMC gene program. Activation of this pathway is required for morphogenetic development of the aorta and ductus arteriosus during embryonic and postnatal survival.
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- 2011
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24. Albiglutide, a long lasting glucagon-like peptide-1 analog, protects the rat heart against ischemia/reperfusion injury: evidence for improving cardiac metabolic efficiency.
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Bao W, Aravindhan K, Alsaid H, Chendrimada T, Szapacs M, Citerone DR, Harpel MR, Willette RN, Lepore JJ, and Jucker BM
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- Animals, Blood Glucose metabolism, Body Weight drug effects, Cyclic AMP metabolism, Energy Metabolism drug effects, Feeding Behavior drug effects, Glucagon-Like Peptide 1 administration & dosage, Glucagon-Like Peptide 1 blood, Glucagon-Like Peptide 1 pharmacology, Heart, Heart Function Tests, Hemodynamics drug effects, In Vitro Techniques, Insulin blood, Lactic Acid blood, Male, Metabolic Networks and Pathways drug effects, Metabolic Networks and Pathways genetics, Myocardial Infarction complications, Myocardial Infarction pathology, Myocardial Infarction physiopathology, Myocardial Reperfusion Injury complications, Myocardial Reperfusion Injury physiopathology, Principal Component Analysis, Rats, Rats, Sprague-Dawley, Transcription, Genetic drug effects, Cardiotonic Agents pharmacology, Glucagon-Like Peptide 1 analogs & derivatives, Myocardial Reperfusion Injury prevention & control, Myocardium metabolism
- Abstract
Background: The cardioprotective effects of glucagon-like peptide-1 (GLP-1) and analogs have been previously reported. We tested the hypothesis that albiglutide, a novel long half-life analog of GLP-1, may protect the heart against I/R injury by increasing carbohydrate utilization and improving cardiac energetic efficiency., Methods/principal Findings: Sprague-Dawley rats were treated with albiglutide and subjected to 30 min myocardial ischemia followed by 24 h reperfusion. Left ventricle infarct size, hemodynamics, function and energetics were determined. In addition, cardiac glucose disposal, carbohydrate metabolism and metabolic gene expression were assessed. Albiglutide significantly reduced infarct size and concomitantly improved post-ischemic hemodynamics, cardiac function and energetic parameters. Albiglutide markedly increased both in vivo and ex vivo cardiac glucose uptake while reducing lactate efflux. Analysis of metabolic substrate utilization directly in the heart showed that albiglutide increased the relative carbohydrate versus fat oxidation which in part was due to an increase in both glucose and lactate oxidation. Metabolic gene expression analysis indicated upregulation of key glucose metabolism genes in the non-ischemic myocardium by albiglutide., Conclusion/significance: Albiglutide reduced myocardial infarct size and improved cardiac function and energetics following myocardial I/R injury. The observed benefits were associated with enhanced myocardial glucose uptake and a shift toward a more energetically favorable substrate metabolism by increasing both glucose and lactate oxidation. These findings suggest that albiglutide may have direct therapeutic potential for improving cardiac energetics and function.
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- 2011
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25. Inhibition of p38 mitogen-activated protein kinase reduces inflammation after coronary vascular injury in humans.
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Sarov-Blat L, Morgan JM, Fernandez P, James R, Fang Z, Hurle MR, Baidoo C, Willette RN, Lepore JJ, Jensen SE, and Sprecher DL
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- Aged, C-Reactive Protein analysis, Coronary Artery Disease therapy, Double-Blind Method, Female, Humans, Hydroxymethylglutaryl-CoA Reductase Inhibitors therapeutic use, Inflammation blood, Male, Middle Aged, Prosthesis Implantation adverse effects, Vascular System Injuries blood, Vascular System Injuries etiology, Angioplasty, Balloon, Coronary adverse effects, Anti-Inflammatory Agents therapeutic use, Coronary Vessels injuries, Stents adverse effects, Vascular System Injuries prevention & control, p38 Mitogen-Activated Protein Kinases antagonists & inhibitors
- Abstract
Objective: To evaluate whether a p38α/β mitogen-activated protein kinase inhibitor, SB-681323, would limit the elevation of an inflammatory marker, high-sensitivity C-reactive protein (hsCRP), after a percutaneous coronary intervention (PCI)., Methods and Results: Coronary artery stents provide benefit by maintaining lumen patency but may incur vascular trauma and inflammation, leading to myocardial damage. A key mediator for such stress signaling is p38 mitogen-activated protein kinase. Patients with angiographically documented coronary artery disease receiving stable statin therapy and about to undergo PCI were randomly selected to receive SB-681323, 7.5 mg (n=46), or placebo (n=46) daily for 28 days, starting 3 days before PCI. On day 3, before PCI, hsCRP was decreased in the SB-681323 group relative to the placebo group (29% lower; P=0.02). After PCI, there was a statistically significant attenuation in the increase in hsCRP in the SB-681323 group relative to the placebo group (37% lower on day 5 [P=0.04]; and 40% lower on day 28 [P=0.003]). There were no adverse safety signals after 28 days of treatment with SB-681323., Conclusions: In the setting of statin therapy, SB-681323 significantly attenuated the post-PCI inflammatory response, as measured by hsCRP. This inflammatory dampening implicates p38 mitogen-activated protein kinase in the poststent response, potentially defining an avenue to limit poststent restenosis.
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- 2010
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26. Chronic inhibition of hypoxia-inducible factor prolyl 4-hydroxylase improves ventricular performance, remodeling, and vascularity after myocardial infarction in the rat.
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Bao W, Qin P, Needle S, Erickson-Miller CL, Duffy KJ, Ariazi JL, Zhao S, Olzinski AR, Behm DJ, Pipes GC, Jucker BM, Hu E, Lepore JJ, and Willette RN
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- Animals, Cell Line, Coronary Vessels metabolism, Coronary Vessels physiopathology, Glycine pharmacology, Hemodynamics drug effects, Hypoxia-Inducible Factor 1, alpha Subunit metabolism, Male, Myocardial Infarction metabolism, Myocardial Infarction physiopathology, Rats, Rats, Inbred Lew, Rats, Sprague-Dawley, Coronary Vessels drug effects, Glycine analogs & derivatives, Hypoxia-Inducible Factor 1 metabolism, Myocardial Infarction drug therapy, Procollagen-Proline Dioxygenase antagonists & inhibitors, Quinolones pharmacology, Ventricular Remodeling drug effects
- Abstract
Background: Hypoxia inducible factors (HIFs) are transcription factors that are regulated by HIF-prolyl 4-hydroxylases (PHDs) in response to changes in oxygen tension. Once activated, HIFs play an important role in angiogenesis, erythropoiesis, proliferation, cell survival, inflammation, and energy metabolism. We hypothesized that GSK360A, a novel orally active HIF-PHD inhibitor, could facilitate local and systemic HIF-1 alpha signaling and protect the failing heart after myocardial infarction (MI)., Methods and Results: GSK360A is a potent (nanomolar) inhibitor of HIF-PHDs (PHD1>PHD2 = PHD3) capable of activating the HIF-1 alpha pathway in a variety of cell types including neonatal rat ventricular myocytes and H9C2 cells. Male rats treated orally with GSK360A (30 mg x kg x d) had a sustained elevation in circulating levels of erythropoietin and hemoglobin and increased hemoxygenase-1 expression in the heart and skeletal muscle. In a rat model of established heart failure with systolic dysfunction induced by ligation of left anterior descending coronary artery, chronic treatment with GSK360A for 28 days prevented the progressive reduction in ejection fraction, ventricular dilation, and increased lung weight, which were observed in the vehicle-treated animals, for up to 3 months. In addition, the microvascular density in the periinfarct region was increased (>2-fold) in GSK360A-treated animals. Treatment was well tolerated (survival was 89% in the GSK360A group vs. 82% in the placebo group)., Conclusions: Chronic post-myocardial infarction treatment with a selective HIF PHD inhibitor (GSK360A) exerts systemic and local effects by stabilizing HIF-1 alpha signaling and improves long-term ventricular function, remodeling, and vascularity in a model of established ventricular dysfunction. These results suggest that HIF-PHD inhibitors may be suitable for the treatment of post-MI remodeling and heart failure.
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- 2010
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27. Characterization and in vivo pharmacological rescue of a Wnt2-Gata6 pathway required for cardiac inflow tract development.
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Tian Y, Yuan L, Goss AM, Wang T, Yang J, Lepore JJ, Zhou D, Schwartz RJ, Patel V, Cohen ED, and Morrisey EE
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- Animals, Disease Models, Animal, Enzyme Inhibitors pharmacology, Female, Fetal Heart drug effects, GATA6 Transcription Factor genetics, Gene Expression Regulation, Developmental drug effects, Glycogen Synthase Kinase 3 antagonists & inhibitors, Glycogen Synthase Kinase 3 beta, Heart Defects, Congenital embryology, Heart Defects, Congenital genetics, Heart Defects, Congenital physiopathology, Humans, Lithium Chloride pharmacology, Mice, Mice, Inbred C57BL, Mice, Knockout, Mice, Mutant Strains, Models, Cardiovascular, Phenotype, Pregnancy, Signal Transduction, Wnt2 Protein deficiency, Wnt2 Protein genetics, Fetal Heart embryology, Fetal Heart physiology, GATA6 Transcription Factor physiology, Wnt2 Protein physiology
- Abstract
Little is understood about the molecular mechanisms underlying the morphogenesis of the posterior pole of the heart. Here we show that Wnt2 is expressed specifically in the developing inflow tract mesoderm, which generates portions of the atria and atrio-ventricular canal. Loss of Wnt2 results in defective development of the posterior pole of the heart, resulting in a phenotype resembling the human congenital heart syndrome complete common atrio-ventricular canal. The number and proliferation of posterior second heart field progenitors is reduced in Wnt2(-/-) mutants. Moreover, these defects can be rescued in a temporally restricted manner through pharmacological inhibition of Gsk-3beta. We also show that Wnt2 works in a feedforward transcriptional loop with Gata6 to regulate posterior cardiac development. These data reveal a molecular pathway regulating the posterior cardiac mesoderm and demonstrate that cardiovascular defects caused by loss of Wnt signaling can be rescued pharmacologically in vivo., (Copyright (c) 2010 Elsevier Inc. All rights reserved.)
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- 2010
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28. BMP type II receptor regulates positioning of outflow tract and remodeling of atrioventricular cushion during cardiogenesis.
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Beppu H, Malhotra R, Beppu Y, Lepore JJ, Parmacek MS, and Bloch KD
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- Animals, Aorta abnormalities, Bone Morphogenetic Protein Receptors, Type II genetics, Cell Proliferation, Female, Heart Septal Defects, Ventricular embryology, Heart Valves abnormalities, Heart Valves embryology, Male, Mesoderm embryology, Mice, Mice, Knockout, Body Patterning physiology, Bone Morphogenetic Protein Receptors, Type II physiology, Cell Differentiation physiology, Endocardial Cushions embryology, Heart embryology
- Abstract
Signaling of bone morphogenetic protein (BMP) via type I and type II receptors is involved in multiple processes contributing to cardiogenesis. To investigate the role of the BMP type II receptor (BMPRII) in heart development, the BMPRII gene was deleted throughout the embryo during gastrulation using a Mox2-Cre transgene. BMPRII(flox/-);Mox2-Cre mice exhibited cardiac defects including double-outlet right ventricle, ventricular septal defect (VSD), atrioventricular (AV) cushion defects, and thickened valve leaflets. To characterize the tissue-specific functions of BMPRII in cardiogenesis, a series of Cre transgenes (alphaMHC-, Tie2-, Wnt1-, and SM22alpha-Cre) was employed. Interestingly, myocardial development was normal when the BMPRII gene was deleted in myocardial cells using Mox2-Cre, alphaMHC-Cre, or SM22alpha-Cre transgenes, suggesting that signaling by other BMP type II receptors may compensate for the absence of BMPRII in the myocardial cells. AV cushion defects including atrial septal defect, membranous VSD, and thickened valve leaflets were found in BMPRII(flox/-);Tie2-Cre mice. Abnormal positioning of the aorta was observed in BMPRII(flox/-);Wnt1-Cre and BMPRII(flox/-);SM22alpha-Cre mice. Taken together, these results demonstrate that endocardial BMPRII expression is required for septal formation and valvulogenesis. Moreover, mesenchymal BMPRII expression in the outflow tract cushion is required for proper positioning of the aorta.
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- 2009
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29. A Gata6-Wnt pathway required for epithelial stem cell development and airway regeneration.
- Author
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Zhang Y, Goss AM, Cohen ED, Kadzik R, Lepore JJ, Muthukumaraswamy K, Yang J, DeMayo FJ, Whitsett JA, Parmacek MS, and Morrisey EE
- Subjects
- Animals, Cell Proliferation, Embryo, Mammalian, Epithelial Cells physiology, Frizzled Receptors physiology, GATA6 Transcription Factor genetics, Gene Expression Profiling, Lung embryology, Lung metabolism, Lung physiology, Mice, Mice, Transgenic, Models, Biological, Molecular Sequence Data, Oligonucleotide Array Sequence Analysis, Receptors, G-Protein-Coupled physiology, Regeneration physiology, Respiratory Mucosa metabolism, Respiratory Physiological Phenomena, Signal Transduction physiology, Stem Cells metabolism, beta Catenin antagonists & inhibitors, GATA6 Transcription Factor physiology, Regeneration genetics, Respiratory Mucosa physiology, Stem Cells physiology, Wnt Proteins physiology
- Abstract
Epithelial organs, including the lung, are known to possess regenerative abilities through activation of endogenous stem cell populations, but the molecular pathways regulating stem cell expansion and regeneration are not well understood. Here we show that Gata6 regulates the temporal appearance and number of bronchioalveolar stem cells (BASCs) in the lung, its absence in Gata6-null lung epithelium leading to the precocious appearance of BASCs and concurrent loss in epithelial differentiation. This expansion of BASCs was the result of a pronounced increase in canonical Wnt signaling in lung epithelium upon loss of Gata6. Expression of the noncanonical Wnt receptor Fzd2 was downregulated in Gata6 mutants and increased Fzd2 or decreased beta-catenin expression rescued, in part, the lung epithelial defects in Gata6 mutants. During lung epithelial regeneration, canonical Wnt signaling was activated in the niche containing BASCs and forced activation of Wnt signaling led to a large increase in BASC numbers. Moreover, Gata6 was required for proper lung epithelial regeneration, and postnatal loss of Gata6 led to increased BASC expansion and decreased differentiation. Together, these data demonstrate that Gata6-regulated Wnt signaling controls the balance between progenitor expansion and epithelial differentiation required for both lung development and regeneration.
- Published
- 2008
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30. Notch signaling in vascular smooth muscle cells is required to pattern the cerebral vasculature.
- Author
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Proweller A, Wright AC, Horng D, Cheng L, Lu MM, Lepore JJ, Pear WS, and Parmacek MS
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- Animals, Body Patterning physiology, Brain growth & development, Cerebral Arteries cytology, Cerebral Arteries growth & development, Cerebral Arteries metabolism, Circle of Willis cytology, Circle of Willis growth & development, Circle of Willis metabolism, Humans, Mice, Mice, Inbred C57BL, Mice, Mutant Strains, Mice, Transgenic, Muscle, Smooth, Vascular cytology, Muscle, Smooth, Vascular growth & development, Myocytes, Smooth Muscle cytology, Myocytes, Smooth Muscle physiology, Neovascularization, Physiologic, Receptors, Notch deficiency, Receptors, Notch genetics, Signal Transduction, Brain blood supply, Muscle, Smooth, Vascular physiology, Receptors, Notch physiology
- Abstract
Stroke is the third leading cause of death and a significant contributor of morbidity in the United States. In humans, suboptimal cerebral collateral circulation within the circle of Willis (CW) predisposes to ischemia and stroke risk in the setting of occlusive carotid artery disease. Unique genes or developmental pathways responsible for proper CW formation are unknown. Herein we characterize a mouse model lacking Notch signaling in vascular smooth muscle cells (vSMCs), in which the animals are intolerant to reduced cerebral blood flow. Remarkably, unilateral carotid artery ligation results in profound neurological sequelae and death. After carotid ligation, perfusion of the ipsilateral cerebral hemisphere was markedly diminished, suggesting an anastomotic deficiency within the CW. High-resolution microcomputed tomographic (micro-CT) imaging revealed profound defects in cerebrovascular patterning, including interruption of the CW and anatomic deformity of the cerebral arteries. These data identify a vSMC-autonomous function for Notch signaling in patterning and collateral formation within the cerebral arterial circulation. The data further implicate genetic or functional deficiencies in Notch signaling in the pathogenesis of anatomic derangements underlying cerebrovascular accidents.
- Published
- 2007
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31. The CREB leucine zipper regulates CREB phosphorylation, cardiomyopathy, and lethality in a transgenic model of heart failure.
- Author
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Huggins GS, Lepore JJ, Greytak S, Patten R, McNamee R, Aronovitz M, Wang PJ, and Reed GL
- Subjects
- Animals, Cardiac Output, Low physiopathology, Cardiomyopathies physiopathology, Cyclic AMP Response Element-Binding Protein genetics, Disease Models, Animal, Female, Leucine Zippers genetics, Male, Mice, Mice, Transgenic, Mutation genetics, Myocardium metabolism, Phosphorylation, Protein Binding, Cardiac Output, Low metabolism, Cardiomyopathies metabolism, Cyclic AMP Response Element-Binding Protein metabolism, Leucine Zippers physiology
- Abstract
Signaling through cAMP plays an important role in heart failure. Phosphorylation of cAMP response element binding protein (CREB) at serine-133 regulates gene expression in the heart. We examined the functional significance of CREB-S133 phosphorylation by comparing transgenic models in which a phosphorylation resistant CREB-S133A mutant containing either an intact or a mutated leucine zipper domain (CREB-S133A-LZ) was expressed in the heart. In vitro, CREB-S133A retained the ability to interact with wild-type CREB, whereas CREB-S133A-LZ did not. In vivo, CREB-S133A and CREB-S133A-LZ were expressed at comparable levels in the heart; however, CREB-S133A markedly suppressed the phosphorylation of endogenous CREB, whereas CREB-S133A-LZ had no effect. The one-year survival of mice from two CREB-S133A-LZ transgenic lines was equivalent to nontransgenic littermate control mice (NTG), whereas transgenic CREB-S133A mice died with heart failure at a median 30 wk of age (P < 0.0001). CREB-S133A mice had an altered gene expression characteristic of the failing heart, whereas CREB-S133A-LZ mice did not. Left ventricular contractile function was substantially reduced in CREB-S133A mice versus NTG mice and only modestly reduced in CREB-S133A-LZ mice (P < 0.02). When considered in light of other studies, these findings indicate that overexpression of the CREB leucine zipper is required for both inhibition of endogenous CREB phosphorylation and cardiomyopathy in this murine model of heart failure.
- Published
- 2007
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32. Wnt/beta-catenin signaling promotes expansion of Isl-1-positive cardiac progenitor cells through regulation of FGF signaling.
- Author
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Cohen ED, Wang Z, Lepore JJ, Lu MM, Taketo MM, Epstein DJ, and Morrisey EE
- Subjects
- Animals, Basic Helix-Loop-Helix Transcription Factors metabolism, Cell Proliferation, Embryo, Mammalian cytology, Embryo, Mammalian embryology, Embryo, Mammalian metabolism, Gene Deletion, Gene Expression Regulation, Developmental, Genetic Markers, Heart embryology, Homeodomain Proteins genetics, LIM-Homeodomain Proteins, Mice, Transcription Factors, beta Catenin deficiency, beta Catenin genetics, Fibroblast Growth Factors metabolism, Homeodomain Proteins metabolism, Myoblasts, Cardiac cytology, Myoblasts, Cardiac metabolism, Signal Transduction, Wnt Proteins metabolism, beta Catenin metabolism
- Abstract
The anterior heart field (AHF), which contributes to the outflow tract and right ventricle of the heart, is defined in part by expression of the LIM homeobox transcription factor Isl-1. The importance of Isl-1-positive cells in cardiac development and homeostasis is underscored by the finding that these cells are required for cardiac development and act as cardiac stem/progenitor cells within the postnatal heart. However, the molecular pathways regulating these cells' expansion and differentiation are poorly understood. We show that Isl-1-positive AHF progenitor cells in mice were responsive to Wnt/beta-catenin signaling, and these responsive cells contributed to the outflow tract and right ventricle of the heart. Loss of Wnt/beta-catenin signaling in the AHF caused defective outflow tract and right ventricular development with a decrease in Isl-1-positive progenitors and loss of FGF signaling. Conversely, Wnt gain of function in these cells led to expansion of Isl-1-positive progenitors with a concomitant increase in FGF signaling through activation of a specific set of FGF ligands including FGF3, FGF10, FGF16, and FGF20. These data reveal what we believe to be a novel Wnt-FGF signaling axis required for expansion of Isl-1-positive AHF progenitors and suggest future therapies to increase the number and function of these cells for cardiac regeneration.
- Published
- 2007
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33. Klf2 is an essential regulator of vascular hemodynamic forces in vivo.
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Lee JS, Yu Q, Shin JT, Sebzda E, Bertozzi C, Chen M, Mericko P, Stadtfeld M, Zhou D, Cheng L, Graf T, MacRae CA, Lepore JJ, Lo CW, and Kahn ML
- Subjects
- Anemia physiopathology, Animals, Arteriovenous Malformations physiopathology, Blood Flow Velocity, Blood Vessels cytology, Blood Vessels drug effects, Cells, Cultured, Embryo, Mammalian cytology, Embryo, Mammalian metabolism, Embryo, Nonmammalian, Endothelium, Vascular cytology, Endothelium, Vascular drug effects, Genes, Lethal, Integrases metabolism, Kruppel-Like Transcription Factors genetics, Mice, Mice, Knockout, Mice, Transgenic, Microfilament Proteins genetics, Microfilament Proteins physiology, Muscle Proteins genetics, Muscle Proteins physiology, Muscle, Smooth cytology, Muscle, Smooth drug effects, Muscle, Smooth metabolism, Myocardium cytology, Myocardium metabolism, Phenylephrine pharmacology, Polymerase Chain Reaction, Promoter Regions, Genetic, Receptor, TIE-2 genetics, Receptor, TIE-2 physiology, Stress, Mechanical, Transcription, Genetic, Umbilical Veins cytology, Umbilical Veins drug effects, Umbilical Veins metabolism, Zebrafish embryology, Zebrafish metabolism, Blood Vessels physiology, Endothelium, Vascular metabolism, Gene Expression Regulation, Developmental, Heart Failure, Kruppel-Like Transcription Factors physiology
- Abstract
Hemodynamic responses that control blood pressure and the distribution of blood flow to different organs are essential for survival. Shear forces generated by blood flow regulate hemodynamic responses, but the molecular and genetic basis for such regulation is not known. The transcription factor KLF2 is activated by fluid shear stress in cultured endothelial cells, where it regulates a large number of vasoactive endothelial genes. Here, we show that Klf2 expression during development mirrors the rise of fluid shear forces, and that endothelial loss of Klf2 results in lethal embryonic heart failure due to a high-cardiac-output state. Klf2 deficiency does not result in anemia or structural vascular defects, and it can be rescued by administration of phenylephrine, a catecholamine that raises vessel tone. These findings identify Klf2 as an essential hemodynamic regulator in vivo and suggest that hemodynamic regulation in response to fluid shear stress is required for cardiovascular development and function.
- Published
- 2006
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34. Impaired notch signaling promotes de novo squamous cell carcinoma formation.
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Proweller A, Tu L, Lepore JJ, Cheng L, Lu MM, Seykora J, Millar SE, Pear WS, and Parmacek MS
- Subjects
- Animals, Carcinoma, Squamous Cell genetics, Carcinoma, Squamous Cell pathology, Cyclin D1 biosynthesis, Cyclin D1 metabolism, Humans, Mice, Mice, Transgenic, Nuclear Proteins biosynthesis, Nuclear Proteins genetics, Receptors, Notch metabolism, Signal Transduction physiology, Skin metabolism, Skin Neoplasms genetics, Skin Neoplasms pathology, Transcription Factors biosynthesis, Transcription Factors genetics, Up-Regulation, beta Catenin metabolism, Carcinoma, Squamous Cell metabolism, Receptors, Notch antagonists & inhibitors, Skin Neoplasms metabolism
- Abstract
Signaling through Notch receptors in the skin has been implicated in the differentiation, proliferation, and survival of keratinocytes, as well as in the pathogenesis of basal cell carcinoma (BCC). To determine the composite function of Notch receptor-mediated signaling in the skin and overcome potential redundancies between receptors, conditional transgenic mice were generated that express the pan-Notch inhibitor, dominant-negative Mastermind Like 1 (DNMAML1), to repress all canonical [CBF-1/Suppressor of hairless/LAG-1 (CSL)-dependent] Notch signaling exclusively in the epidermis. Here, we report that DNMAML1 mice display hyperplastic epidermis and spontaneously develop cutaneous squamous cell carcinoma (SCC) as well as dysplastic precursor lesions, actinic keratoses. Mice expressing epidermal DNMAML1 display enhanced accumulation of nuclear beta-catenin and cyclin D1 in suprabasilar keratinocytes and in lesional cells from SCCs, which was also observed in human cutaneous SCC. These results suggest a model wherein CSL-dependent Notch signaling confers protection against cutaneous SCC. The demonstration that inhibition of canonical Notch signaling in mice leads to spontaneous formation of SCC and recapitulates the disease in humans yields fundamental insights into the pathogenesis of SCC and provides a unique in vivo animal model to examine the pathobiology of cutaneous SCC and for evaluating novel therapies.
- Published
- 2006
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35. GATA-6 regulates semaphorin 3C and is required in cardiac neural crest for cardiovascular morphogenesis.
- Author
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Lepore JJ, Mericko PA, Cheng L, Lu MM, Morrisey EE, and Parmacek MS
- Subjects
- Animals, Aorta growth & development, Aorta metabolism, Cell Differentiation, Female, GATA6 Transcription Factor genetics, Gene Deletion, Gene Targeting, Heart Defects, Congenital genetics, In Situ Hybridization, Male, Mice, Mice, Inbred C57BL, Models, Genetic, Morphogenesis, Muscle, Smooth, Vascular metabolism, Myocytes, Smooth Muscle, Semaphorins metabolism, Species Specificity, Transfection, Cardiovascular Abnormalities genetics, GATA6 Transcription Factor metabolism, Heart embryology, Neural Crest metabolism, Semaphorins genetics
- Abstract
GATA transcription factors play critical roles in restricting cell lineage differentiation during development. Here, we show that conditional inactivation of GATA-6 in VSMCs results in perinatal mortality from a spectrum of cardiovascular defects, including interrupted aortic arch and persistent truncus arteriosus. Inactivation of GATA-6 in neural crest recapitulates these abnormalities, demonstrating a cell-autonomous requirement for GATA-6 in neural crest-derived SMCs. Surprisingly, the observed defects do not result from impaired SMC differentiation but rather are associated with severely attenuated expression of semaphorin 3C, a signaling molecule critical for both neuronal and vascular patterning. Thus, the primary function of GATA-6 during cardiovascular development is to regulate morphogenetic patterning of the cardiac outflow tract and aortic arch. These findings provide new insights into the conserved functions of the GATA-4, -5, and -6 subfamily members and identify GATA-6 and GATA-6-regulated genes as candidates involved in the pathogenesis of congenital heart disease.
- Published
- 2006
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36. Combined administration of intravenous dipyridamole and inhaled nitric oxide to assess reversibility of pulmonary arterial hypertension in potential cardiac transplant recipients.
- Author
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Lepore JJ, Dec GW, Zapol WM, Bloch KD, and Semigran MJ
- Subjects
- Administration, Inhalation, Adult, Aged, Blood Pressure drug effects, Drug Combinations, Female, Humans, Infusions, Intravenous, Male, Middle Aged, Phosphodiesterase Inhibitors administration & dosage, Pulmonary Artery physiology, Dipyridamole administration & dosage, Heart Transplantation, Nitric Oxide administration & dosage, Vascular Resistance drug effects
- Abstract
Background: Irreversible, severe pulmonary hypertension (PH) can produce right heart failure and early mortality after cardiac transplantation. We hypothesized that dipyridamole, an inhibitor of Type 5 phosphodiesterase, would augment the ability of inhaled nitric oxide (NO) to identify reversibility of PH., Methods: In 9 patients with congestive heart failure (CHF) and severe PH who were breathing 100% oxygen during right heart catheterization, we administered inhaled NO (80 ppm) alone and in combination with intravenous dipyridamole (0.2-mg/kg bolus, with an infusion of 0.0375 mg/kg/min)., Results: Compared with breathing oxygen alone, NO inhalation decreased pulmonary artery pressure and pulmonary vascular resistance (PVR) (by 10 +/- 4% and 26 +/- 12% [mean +/- SEM], respectively; both p < 0.05). The combination of NO and dipyridamole reduced PVR (43 +/- 7%; p < 0.05) to a greater extent than did administration of NO alone, and increased the duration of pulmonary vasodilation produced by NO inhalation. Combined administration of inhaled NO and intravenous dipyridamole increased cardiac index (by 23 +/- 10%) and reduced SVR (by 19 +/- 6%, both p < 0.05) without changing systemic arterial pressure. NO inhalation reduced PVR to <200 dyne x s/cm5 in 3 of 7 patients who had a PVR of >200 dyne x s/cm5 when breathing oxygen alone, whereas the combination of NO and dipyridamole decreased PVR to <200 dyne.s/cm(5) in 2 additional patients., Conclusions: Intravenous dipyridamole augments and prolongs the pulmonary vasodilator effects of inhaled NO in CHF patients with severe PH and, when administered in combination with NO inhalation, can identify PH reversibility in potential cardiac transplant recipients in whom a pulmonary vasodilator response to inhalation of NO alone is not observed.
- Published
- 2005
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37. High-efficiency somatic mutagenesis in smooth muscle cells and cardiac myocytes in SM22alpha-Cre transgenic mice.
- Author
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Lepore JJ, Cheng L, Min Lu M, Mericko PA, Morrisey EE, and Parmacek MS
- Subjects
- Animals, Female, Integrases metabolism, Male, Mice, Models, Animal, Mutagenesis, Myocytes, Cardiac, Recombination, Genetic, Cardiovascular System growth & development, Mice, Transgenic, Microfilament Proteins genetics, Microfilament Proteins physiology, Muscle Proteins genetics, Muscle Proteins physiology, Muscle, Smooth, Vascular cytology, beta-Galactosidase biosynthesis
- Abstract
The cytoskeletal protein SM22alpha is expressed in visceral and vascular smooth muscle cells (SMCs), in cardiac myocytes, and in the myotomal components of the somites during murine embryonic development. In this report, we describe the generation and characterization of transgenic mice expressing Cre-recombinase under the transcriptional control of the -2.8-kb SM22alpha promoter. Following interbreeding with the R26R reporter strain, Cre-dependent beta-galactosidase expression was observed as early as embryonic day 9.5 in SMCs of the developing vasculature, in cardiac myocytes, but not in the somites. In adult mice, Cre-mediated recombination was observed in vascular SMCs throughout the venous and arterial systems, in visceral SMCs in multiple organs, and in cardiac, but not skeletal muscle. Importantly, Cre-mediated recombination was present in nearly 100% of arterial SMCs, including in the aorta. These mice are thus an important new tool for performing in vivo loss-of-function studies of genes expressed in vascular SMCs., (Copyright (c) 2005 Wiley-Liss, Inc.)
- Published
- 2005
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38. MRL mice fail to heal the heart in response to ischemia-reperfusion injury.
- Author
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Abdullah I, Lepore JJ, Epstein JA, Parmacek MS, and Gruber PJ
- Subjects
- Animals, Heart Ventricles pathology, Male, Mice, Mice, Inbred Strains, Models, Animal, Myocardial Infarction pathology, Myocardial Reperfusion Injury pathology, Heart Ventricles physiopathology, Myocardial Infarction physiopathology, Myocardial Reperfusion Injury physiopathology, Myocardium pathology, Wound Healing physiology
- Abstract
The MRL/MpJ mouse strain has been reported to recover after right ventricular cryoinjury without scar formation or evidence of ventricular dysfunction, suggesting that this mouse strain harbors genetic traits that confer the capacity for adult myocardium to regenerate. We therefore sought to assess the capacity of adult MRL myocardium to regenerate in a left ventricular ischemia-reperfusion model of myocardial infarction, which more closely recapitulates injury that occurs in human disease. MRL (n = 13) and control C57/Bl6 (n = 12) mice underwent transient occlusion of the left anterior descending coronary artery. After 10 weeks, MRL and C57Bl/6 mice were euthanized and the extent of infarcted myocardium quantified with (2,3,5)-triphenyltetrazolium chloride and trichrome staining. There was no evidence of resistance to cardiac injury or of reduced scar formation in the MRL mice compared to C57/Bl6 controls. Myocardial infarct size (percentage of total heart weight +/- SEM) did not significantly differ between MRL and C57/Bl6 controls (18.9 +/- 1.8% for MRL vs. 15.7 + 1.3% for C57/Bl6, p = 0.20). Thickness of the infarcted anterior LV wall at the mid-papillary level normalized to body weight was not significantly different between the two groups (0.017 + 0.003 mm/mg for MRL and 0.017 + 0.002 mm/mg for C57/BL6, p = 0.91). Trichrome staining showed intense scar formation in both C57/BL6 and MRL hearts. We conclude that there appears to be no effect of the MRL genetic background on resistance to myocardial infarction in mice.
- Published
- 2005
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39. GATA-6 regulates genes promoting synthetic functions in vascular smooth muscle cells.
- Author
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Lepore JJ, Cappola TP, Mericko PA, Morrisey EE, and Parmacek MS
- Subjects
- Animals, Cell Differentiation, Cells, Cultured metabolism, DNA-Binding Proteins genetics, Drosophila Proteins, Endothelin-1 biosynthesis, Endothelin-1 genetics, GATA6 Transcription Factor, Gene Expression Profiling, Homeodomain Proteins genetics, Humans, Mice, Muscle Proteins genetics, NIH 3T3 Cells metabolism, Nuclear Proteins genetics, Nuclear Proteins physiology, Receptor, Angiotensin, Type 1 biosynthesis, Receptor, Angiotensin, Type 1 genetics, Recombinant Fusion Proteins physiology, Repressor Proteins physiology, Reverse Transcriptase Polymerase Chain Reaction, Trans-Activators genetics, Trans-Activators physiology, Transcription Factors genetics, Transcription, Genetic, DNA-Binding Proteins physiology, Muscle Proteins biosynthesis, Muscle, Smooth, Vascular metabolism, Myocytes, Smooth Muscle metabolism, Transcription Factors physiology
- Abstract
Objective: Previous studies suggested the zinc-finger transcription factor GATA-6 inhibits vascular smooth muscle cell (VSMC) proliferation and promotes the contractile VSMC phenotype. The objective of this study was to identify bona fide target genes regulated by GATA-6 in VSMCs., Methods and Results: Microarray analyses were performed comparing mRNA from rat aortic smooth muscle cells (SMCs) infected with either adenovirus encoding a dominant-negative GATA-6/engrailed fusion protein or with control adenovirus. These studies identified 122 genes differentially expressed by at least 2-fold, including multiple genes involved in cell-cell signaling and cell-matrix interactions. Among these, endothelin-1 and the angiotensin type(1a) (AT(1a)) receptor are known to be induced in VSMCs in response to inflammatory stimuli and to be expressed in a GATA-dependent manner in cardiac myocytes in response to hemodynamic stress. Consistent with these findings, the endothelin-1 and AT(1a) receptor promoters were activated by forced expression of GATA-6 and repressed by forced expression of GATA-6/engrailed. Surprisingly, genes encoding SMC contractile proteins were not altered, and myocardin-induced SMC differentiation was not impaired in GATA-6(-/-) embryonic stem cells., Conclusions: These data demonstrate that in VSMCs, GATA-6 regulates a set of genes associated with synthetic SMC functions and suggest that this transcriptional pathway may be independent from myocardin-induced SMC differentiation. An unbiased microarray screen of genes regulated by GATA-6 in VSMCs identified multiple genes involved in cell-cell signaling and cell-matrix interactions. The endothelin-1 and the AT1a receptor genes were shown to be direct GATA-6 target genes. These data suggest that GATA-6 plays a role in promoting synthetic functions in VSMCs.
- Published
- 2005
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40. Hemodynamic effects of inhaled nitric oxide in right ventricular myocardial infarction and cardiogenic shock.
- Author
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Inglessis I, Shin JT, Lepore JJ, Palacios IF, Zapol WM, Bloch KD, and Semigran MJ
- Subjects
- Administration, Inhalation, Adult, Aged, Aged, 80 and over, Echocardiography, Electrocardiography, Female, Hemodynamics, Humans, Male, Middle Aged, Myocardial Infarction diagnostic imaging, Myocardial Infarction physiopathology, Nitric Oxide administration & dosage, Prospective Studies, Shock, Cardiogenic physiopathology, Treatment Outcome, Vasodilator Agents administration & dosage, Ventricular Dysfunction, Right diagnostic imaging, Ventricular Dysfunction, Right physiopathology, Myocardial Infarction drug therapy, Nitric Oxide therapeutic use, Shock, Cardiogenic drug therapy, Vasodilator Agents therapeutic use, Ventricular Dysfunction, Right drug therapy
- Abstract
Objectives: We sought to determine whether or not inhaled nitric oxide (NO) could improve hemodynamic function in patients with right ventricular myocardial infarction (RVMI) and cardiogenic shock (CS)., Background: Inhaled NO is a selective pulmonary vasodilator that can decrease right ventricular afterload., Methods: Thirteen patients (7 males and 6 females, age 65 +/- 3 years) presenting with electrocardiographic, echocardiographic, and hemodynamic evidence of acute inferior myocardial infarction associated with RVMI and CS were studied. After administration of supplemental oxygen (inspired oxygen fraction [F(i)O(2)] = 1.0), hemodynamic measurements were recorded before, during inhalation of NO (80 ppm at F(i)O(2) = 0.90) for 10 min, and 10 min after NO inhalation was discontinued (F(i)O(2) = 1.0)., Results: Breathing NO decreased the mean right atrial pressure by 12 +/- 3%, mean pulmonary arterial pressure by 13 +/- 2%, and pulmonary vascular resistance by 36 +/- 8% (all p < 0.05). Nitric oxide inhalation increased the cardiac index by 24 +/- 11% and the stroke volume index by 23 +/- 12% (p < 0.05). The NO administration did not change systemic arterial or pulmonary capillary wedge pressures. Contrast echocardiography identified three patients with a patent foramen ovale and right-to-left shunt flow while breathing at F(i)O(2) = 1.0. Breathing NO decreased shunt flow by 56 +/- 5% (p < 0.05) and was associated with markedly improved systemic oxygen saturation., Conclusions: Nitric oxide inhalation results in acute hemodynamic improvement when administered to patients with RVMI and CS.
- Published
- 2004
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41. Megakaryoblastic leukemia factor-1 transduces cytoskeletal signals and induces smooth muscle cell differentiation from undifferentiated embryonic stem cells.
- Author
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Du KL, Chen M, Li J, Lepore JJ, Mericko P, and Parmacek MS
- Subjects
- Animals, Blotting, Northern, COS Cells, Cell Differentiation, Cell Nucleus metabolism, Cells, Cultured, Chromatin metabolism, Cytoplasm metabolism, DNA, Complementary metabolism, Genes, Dominant, Humans, Immunohistochemistry, Luciferases metabolism, Mice, NIH 3T3 Cells, Nuclear Proteins metabolism, Plasmids metabolism, Precipitin Tests, Promoter Regions, Genetic, Protein Binding, Protein Structure, Tertiary, Protein Transport, Reverse Transcriptase Polymerase Chain Reaction, Tissue Distribution, Trans-Activators metabolism, Transcriptional Activation, Transfection, Two-Hybrid System Techniques, Cytoskeleton metabolism, DNA-Binding Proteins physiology, Embryo, Mammalian cytology, Myocytes, Smooth Muscle cytology, Oncogene Proteins, Fusion physiology, Signal Transduction, Stem Cells cytology
- Abstract
The SAP domain transcription factor myocardin plays a critical role in the transcriptional program regulating smooth muscle cell differentiation. In this report, we describe the capacity of myocardin to physically associate with megakaryoblastic leukemia factor-1 (MKL1) and characterize the function of MKL1 in smooth muscle cells (SMCs). The MKL1 gene is expressed in most human tissues and myocardin and MKL are co-expressed in SMCs. MKL1 and myocardin physically associate via conserved leucine zipper domains. Overexpression of MKL1 transactivates serum response factor (SRF)-dependent SMC-restricted transcriptional regulatory elements including the SM22alpha promoter, smooth muscle myosin heavy chain promoter/enhancer, and SM-alpha-actin promoter/enhancer in non-SMCs. Moreover, forced expression of MKL1 and SRF in undifferentiated SRF(-/-) embryonic stem cells activates multiple endogenous SMC-restricted genes at levels equivalent to, or exceeding, myocardin. Forced expression of a dominant-negative MKL1 mutant reduces myocardin-induced activation of the SMC-specific SM22alpha promoter. In NIH3T3 fibroblasts MKL1 localizes to the cytoplasm and translocates to the nucleus in response to serum stimulation, actin treadmilling, and RhoA signaling. In contrast, in SMCs MKL1 is observed exclusively in the nucleus regardless of serum conditions or RhoA signaling. However, when actin polymerization is disrupted MKL1 translocates from the nucleus to the cytoplasm in SMCs. Together, these data were consistent with a model wherein MKL1 transduces signals from the cytoskeleton to the nucleus in SMCs and regulates SRF-dependent SMC differentiation autonomously or in concert with myocardin.
- Published
- 2004
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42. Cardiac hypertrophy and histone deacetylase-dependent transcriptional repression mediated by the atypical homeodomain protein Hop.
- Author
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Kook H, Lepore JJ, Gitler AD, Lu MM, Wing-Man Yung W, Mackay J, Zhou R, Ferrari V, Gruber P, and Epstein JA
- Subjects
- Animals, Cardiomegaly genetics, Cardiotonic Agents metabolism, Cell Line, Gene Expression Regulation, Hemodynamics, Homeodomain Proteins genetics, Humans, Isoproterenol metabolism, Mice, Mice, Transgenic, Myocardium pathology, Repressor Proteins genetics, Serum Response Factor genetics, Serum Response Factor metabolism, Survival Rate, Cardiomegaly metabolism, Histone Deacetylases metabolism, Homeodomain Proteins metabolism, Myocardium metabolism, Repressor Proteins metabolism, Transcription, Genetic
- Abstract
Activation of multiple pathways is associated with cardiac hypertrophy and heart failure. Repression of antihypertrophic pathways has rarely been demonstrated to cause cardiac hypertrophy in vivo. Hop is an unusual homeodomain protein that is expressed by embryonic and postnatal cardiac myocytes. Unlike other homeodomain proteins, Hop does not bind DNA. Rather, it modulates cardiac growth and proliferation by inhibiting the transcriptional activity of serum response factor (SRF) in cardiomyocytes. Here we show that Hop can inhibit SRF-dependent transcriptional activation by recruiting histone deacetylase (HDAC) activity and can form a complex that includes HDAC2. Transgenic mice that overexpress Hop develop severe cardiac hypertrophy, cardiac fibrosis, and premature death. A mutant form of Hop, which does not recruit HDAC activity, does not induce hypertrophy. Treatment of Hop transgenic mice with trichostatin A, an HDAC inhibitor, prevents hypertrophy. In addition, trichostatin A also attenuates hypertrophy induced by infusion of isoproterenol. Thus, chromatin remodeling and repression of otherwise active transcriptional processes can result in hypertrophy and heart failure, and this process can be blocked with chemical HDAC inhibitors.
- Published
- 2003
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43. Right-to-left shunting through a patent foramen ovale in right ventricular infarction: improvement of hypoxemia and hemodynamics with inhaled nitric oxide.
- Author
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Fessler MB, Lepore JJ, Thompson BT, and Semigran MJ
- Subjects
- Aged, Blood Gas Analysis, Heart Septal Defects, Atrial physiopathology, Humans, Male, Nitric Oxide administration & dosage, Oxygen Consumption drug effects, Vasodilator Agents administration & dosage, Ventricular Dysfunction, Right physiopathology, Heart Septal Defects, Atrial complications, Hemodynamics drug effects, Hypoxia drug therapy, Hypoxia etiology, Myocardial Infarction complications, Nitric Oxide therapeutic use, Vasodilator Agents therapeutic use, Ventricular Dysfunction, Right complications
- Abstract
Inhaled nitric oxide is a selective pulmonary vasodilator that has been used successfully to treat hemodynamic embarrassment and right-to-left interatrial shunting in acute right heart failure. Previous reports have been in the setting of disorders causing elevated right heart afterload, such as pulmonary embolism, acute respiratory distress syndrome, and chronic obstructive pulmonary disease. Right ventricular infarction is a less common, but important cause of acute right heart failure with which the intensivist should be familiar. We report a patient with right ventricular infarction for whom cardiogenic shock and refractory hypoxemia due to right-to-left interatrial shunting were effectively treated with inhaled nitric oxide. The potential for broader application of inhaled nitric oxide as a therapy for right ventricular infarction is discussed.
- Published
- 2003
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44. Adenovirus-catheter compatibility increases gene expression after delivery to porcine myocardium.
- Author
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Naimark WA, Lepore JJ, Klugherz BD, Wang Z, Guy TS, Osman H, Moainie SL, Gorman RC, Reed G, Gorman JH 3rd, Palasis M, Parmacek MS, and Wilensky RL
- Subjects
- Alloys, Animals, Cardiac Catheterization, Genes, Reporter, Stainless Steel, Swine, Adenoviridae, Gene Transfer Techniques, Genetic Vectors administration & dosage, Myocardium metabolism
- Abstract
Endomyocardial injection of adenoviral gene vectors enables localized delivery to comprised myocardial tissue. However, many materials used in endomyocardial delivery catheters may not be compatible with adenoviral gene vectors. In this study, a series of catheter-based endocardial and epicardial (direct visualization) procedures were performed to assess catheter-adenovirus compatibility in an in vivo model. A standard Nitinol-stainless steel (Ni-SS) catheter was compared with a novel Stiletto catheter designed for improved biocompatibility. In 4 animals 40 endocardial injections of adenovirus encoding beta-galactosidase (beta-Gal) were performed with the 2 catheters. After sectioning of the hearts only 8 of 20 Ni-SS beta-Gal+ sites could be identified (40% retrieval) whereas 16 of the 20 Stiletto injection sites were identified (80%). Within these areas successful transfection was observed (12.2 +/- 4.0 beta-Gal+ cells/high-power field [HPF] in the Ni-SS group vs. 30.1 +/- 6.8 beta-Gal+ cells/HPF in the Stiletto group; p = 0.03). After epicardial delivery to distinct areas of the myocardium adenoviral delivery as assayed by beta-galactosidase protein activity was >21 +/- 16-fold (range, 5 to >43-fold) greater than after Stiletto delivery. In conclusion, this study highlights the importance of adenovirus-material compatibility in gene delivery to the myocardium. Efficiency was greater when using the catheter designed to enhance biocompatibility.
- Published
- 2003
- Full Text
- View/download PDF
45. Regulation of blood and lymphatic vascular separation by signaling proteins SLP-76 and Syk.
- Author
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Abtahian F, Guerriero A, Sebzda E, Lu MM, Zhou R, Mocsai A, Myers EE, Huang B, Jackson DG, Ferrari VA, Tybulewicz V, Lowell CA, Lepore JJ, Koretzky GA, and Kahn ML
- Subjects
- Adaptor Proteins, Signal Transducing, Animals, Animals, Newborn, Antigens, CD34 metabolism, Blood Vessels abnormalities, Blood Vessels cytology, Blood Vessels metabolism, Bone Marrow Cells cytology, Bone Marrow Cells physiology, Bone Marrow Transplantation, Dextrans, Endothelium, Lymphatic cytology, Endothelium, Lymphatic metabolism, Endothelium, Vascular cytology, Endothelium, Vascular metabolism, Enzyme Precursors genetics, Glycoproteins metabolism, Hemorrhage, Homeodomain Proteins genetics, Homeodomain Proteins metabolism, Intestines blood supply, Intracellular Signaling Peptides and Proteins, Lymphatic System abnormalities, Lymphatic System cytology, Lymphatic System metabolism, Membrane Transport Proteins, Mesenteric Arteries abnormalities, Mesenteric Veins abnormalities, Mice, Phosphoproteins genetics, Protein-Tyrosine Kinases genetics, Stem Cells physiology, Syk Kinase, Tumor Suppressor Proteins, Vascular Endothelial Growth Factor Receptor-3 metabolism, Veins cytology, Veins embryology, Veins metabolism, Blood Vessels embryology, Enzyme Precursors metabolism, Fluorescein-5-isothiocyanate analogs & derivatives, Lymphatic System embryology, Phosphoproteins metabolism, Protein-Tyrosine Kinases metabolism, Signal Transduction
- Abstract
Lymphatic vessels develop from specialized endothelial cells in preexisting blood vessels, but the molecular signals that regulate this separation are unknown. Here we identify a failure to separate emerging lymphatic vessels from blood vessels in mice lacking the hematopoietic signaling protein SLP-76 or Syk. Blood-lymphatic connections lead to embryonic hemorrhage and arteriovenous shunting. Expression of slp-76 could not be detected in endothelial cells, and blood-filled lymphatics also arose in wild-type mice reconstituted with SLP-76-deficient bone marrow. These studies reveal a hematopoietic signaling pathway required for separation of the two major vascular networks in mammals.
- Published
- 2003
- Full Text
- View/download PDF
46. Effect of sildenafil on the acute pulmonary vasodilator response to inhaled nitric oxide in adults with primary pulmonary hypertension.
- Author
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Lepore JJ, Maroo A, Pereira NL, Ginns LC, Dec GW, Zapol WM, Bloch KD, and Semigran MJ
- Subjects
- Administration, Inhalation, Adult, Aged, Boston, Drug Therapy, Combination, Female, Humans, Male, Middle Aged, Oxygen therapeutic use, Pulmonary Wedge Pressure drug effects, Purines, Sildenafil Citrate, Sulfones, Time Factors, Treatment Outcome, Vascular Resistance drug effects, Vasoconstriction drug effects, Ventricular Pressure drug effects, Hypertension, Pulmonary drug therapy, Lung blood supply, Lung drug effects, Nitric Oxide therapeutic use, Piperazines therapeutic use, Vasodilation drug effects, Vasodilator Agents therapeutic use
- Published
- 2002
- Full Text
- View/download PDF
47. Oxygen therapy improves cardiac index and pulmonary vascular resistance in patients with pulmonary hypertension.
- Author
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Roberts DH, Lepore JJ, Maroo A, Semigran MJ, and Ginns LC
- Subjects
- Adult, Aged, Blood Pressure, Female, Hemodynamics, Humans, Hypertension, Pulmonary blood, Hypertension, Pulmonary physiopathology, Male, Middle Aged, Oxygen blood, Pulmonary Artery physiopathology, Vasodilation, Cardiac Output, Hypertension, Pulmonary therapy, Oxygen Inhalation Therapy, Vascular Resistance
- Abstract
Study Objectives: We tested the hypothesis that breathing 100% oxygen could result in selective pulmonary vasodilatation in patients with pulmonary hypertension, including those patients who would not meet current Health Care Finance Administration guidelines for long-term oxygen therapy., Design, Setting, and Patients: From 1996 to 1999, 23 adult patients (mean +/- SEM age, 51 +/- 4 years) with pulmonary arterial hypertension without left-heart failure underwent cardiac catheterization in a university teaching hospital while breathing air and then 100% oxygen., Measurements and Results: Treatment with 100% oxygen increased arterial oxygen saturation (91 +/- 1% to 99 +/- 0.1%, p < 0.05) and PaO(2) (64 +/- 3 to 309 +/- 28 mm Hg, p < 0.05). Treatment with 100% oxygen also decreased mean pulmonary artery pressure (56 +/- 3 to 53 +/- 2 mm Hg, p < 0.05) and increased cardiac index (2.1 +/- 0.1 to 2.5 +/- 0.2 L/min/m(2), p < 0.05). Calculated mean pulmonary vascular resistance (PVR) decreased from 14.1 +/- 1.4 to 10.6 +/- 1.0 Wood units (p < 0.05). Vasodilatation with 100% oxygen occurred preferentially in the pulmonary circulation (PVR/systemic vascular resistance, 0.53 +/- 0.04 to 0.48 +/- 0.03; p < 0.05). The magnitude of the PVR response to oxygen therapy was correlated only with decreasing patient age (r = 0.45, p < 0.05)., Conclusions: Treatment with 100% oxygen is a selective pulmonary vasodilator in patients with pulmonary hypertension, regardless of primary diagnosis, baseline oxygenation, or right ventricular function. Development of disease-specific oxygen prescription guidelines warrants consideration.
- Published
- 2001
- Full Text
- View/download PDF
48. Biocompatibility of cardiovascular gene delivery catheters with adenovirus vectors: an important determinant of the efficiency of cardiovascular gene transfer.
- Author
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Marshall DJ, Palasis M, Lepore JJ, and Leiden JM
- Subjects
- Alloys, Defective Viruses, HeLa Cells virology, Humans, Materials Testing, Serum Albumin metabolism, Stainless Steel, beta-Galactosidase metabolism, Adenoviridae physiology, Biocompatible Materials, Cardiovascular System virology, Catheterization instrumentation, Genetic Therapy, Genetic Vectors, Transfection methods
- Abstract
Gene therapy approaches hold promise for the treatment of a wide variety of cardiovascular diseases. Many strategies for cardiovascular gene therapy involve catheter-mediated vector delivery via intramyocardial injection, intracoronary infusion, or direct gene transfer into the vessel wall. Several different gene delivery catheters have been developed and utilized in preclinical and clinical studies of cardiovascular gene therapy. However, rigorous studies of the biocompatibility of these catheters with gene therapy vectors have not yet been reported. In this report, we have examined the compatibility of cardiovascular gene therapy catheters and catheter constituents with first-generation E1/E3-deleted adenovirus vectors. We show that (i) currently available catheters rapidly and efficiently inactivate adenovirus vector infectivity; (ii) this inactivation is mediated by a variety of commonly used catheter constituents including stainless steel, nitinol, and polycarbonate; (iii) catheter-mediated inactivation of adenovirus vectors can be prevented by preflushing catheters with solutions of serum albumin; and (iv) it is possible to identify a set of catheter materials that are compatible with current adenovirus vectors. These results underscore the importance of catheter/vector compatibility and suggest methods for increasing the efficiency of catheter-mediated cardiovascular gene therapy.
- Published
- 2000
- Full Text
- View/download PDF
49. Three members of the nitric oxide synthase II gene family (NOS2A, NOS2B, and NOS2C) colocalize to human chromosome 17.
- Author
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Bloch KD, Wolfram JR, Brown DM, Roberts JD Jr, Zapol DG, Lepore JJ, Filippov G, Thomas JE, Jacob HJ, and Bloch DB
- Subjects
- Amino Acid Sequence, Animals, Base Sequence, Cattle, Cloning, Molecular, DNA, Complementary genetics, Humans, Hybrid Cells, Mice, Molecular Sequence Data, Chromosome Mapping, Chromosomes, Human, Pair 17, Multigene Family, Nitric Oxide Synthase genetics
- Abstract
Nitric oxide synthases (NOSs) are a family of enzymes responsible for the synthesis of nitric oxide from L-arginine and molecular oxygen. Three human NOS enzymes (I, II, and III) with differing cellular distribution and regulatory mechanisms have been identified. To determine whether additional NOSs are encoded in the human genome, a bovine NOS II-related cDNA was used to screen two human genomic libraries. Clones containing three independent genes were isolated. One clone encoded the previously identified NOS II gene (NOS2A). The two other genes specified amino acids homologous, but not identical, to human NOS II (NOS2B and NOS2C). Southern blot hybridization demonstrated that all three genes are present in the human genome. DNA from human-mouse somatic cell hybrids were used to determine the chromosomal location of the NOS II-related genes. All three NOS II-related genes colocalized to human chromosome 17 between bands p13.1 and q25. These observations suggest that there is more than one NOS II-related gene in the human genome. This finding may have important implications for the design of NOS isoform-specific inhibitors.
- Published
- 1995
- Full Text
- View/download PDF
50. Ketocholanic acids as an adjunct in management of high fat diet allergies.
- Author
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LEPORE JJ
- Subjects
- Humans, Bile Acids and Salts therapeutic use, Dehydrocholic Acid, Diet, High-Fat, Fats, Hypersensitivity etiology, Immune System Diseases, Salts
- Published
- 1955
- Full Text
- View/download PDF
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