2024
Quantitative Assessment of Mitochondrial Morphology and Electrophysiological Function in the Diabetic Heart
Cacheux M, Rudokas M, Tieu A, Rizk J, Hummel M, Akar F. Quantitative Assessment of Mitochondrial Morphology and Electrophysiological Function in the Diabetic Heart. Methods In Molecular Biology 2024, 2803: 75-86. PMID: 38676886, DOI: 10.1007/978-1-0716-3846-0_6.Peer-Reviewed Original ResearchConceptsMitochondrial shapeMitochondrial networkMitochondrial architectureSubcellular localizationMitochondrial morphologyDiabetic heartOxidative phosphorylationATP synthesisAction potentialsSarcolemmal ion channelsExcitation-contraction couplingFission eventsOptical action potentialsExcitation-contractionCardiac myocytesElectrophysiological properties
2016
Reducing mitochondrial bound hexokinase II mediates transition from non-injurious into injurious ischemia/reperfusion of the intact heart
Nederlof R, Gürel-Gurevin E, Eerbeek O, Xie C, Deijs GS, Konkel M, Hu J, Weber NC, Schumacher CA, Baartscheer A, Mik EG, Hollmann MW, Akar FG, Zuurbier CJ. Reducing mitochondrial bound hexokinase II mediates transition from non-injurious into injurious ischemia/reperfusion of the intact heart. Journal Of Physiology And Biochemistry 2016, 73: 323-333. PMID: 28258543, PMCID: PMC5534207, DOI: 10.1007/s13105-017-0555-3.Peer-Reviewed Original ResearchConceptsIschemia/reperfusionR injuryCardiac energeticsRecovery of functionHexokinase IISignificant LDH releasePossible underlying mechanismsIschemic insultCardiac recoveryControl heartsMtHKIIReperfusionIschemiaDHE fluorescenceRat heartR intervalLDH releasePeptide treatmentIntact heartInjuryUnderlying mechanismHeartMVO2NecrosisTreatment
2014
Effect of bortezomib on the efficacy of AAV9.SERCA2a treatment to preserve cardiac function in a rat pressure-overload model of heart failure
Chaanine A, Nonnenmacher M, Kohlbrenner E, Jin D, Kovacic J, Akar F, Hajjar R, Weber T. Effect of bortezomib on the efficacy of AAV9.SERCA2a treatment to preserve cardiac function in a rat pressure-overload model of heart failure. Gene Therapy 2014, 21: 379-386. PMID: 24572786, PMCID: PMC3976435, DOI: 10.1038/gt.2014.7.Peer-Reviewed Original ResearchConceptsHeart failureCardiac functionRodent heart failure modelsRat cardiomyocytesHeart failure modelPressure overload modelEffect of bortezomibProteasome inhibitor bortezomibNeonatal rat cardiomyocytesAdult rat cardiomyocytesWestern blot analysisSERCA2a proteinPressure-volume analysisSERCA2a levelsBortezomib treatmentConcurrent treatmentSERCA2a mRNAInhibitor bortezomibBortezomibHeart samplesHuman SERCA2aSerotype 1Proteasome inhibitorsAAV serotypes 1Proteasome inhibition
2013
Advancing functional engineered cardiac tissues toward a preclinical model of human myocardium
Turnbull IC, Karakikes I, Serrao GW, Backeris P, Lee J, Xie C, Senyei G, Gordon RE, Li RA, Akar FG, Hajjar RJ, Hulot J, Costa KD. Advancing functional engineered cardiac tissues toward a preclinical model of human myocardium. The FASEB Journal 2013, 28: 644-654. PMID: 24174427, PMCID: PMC3898643, DOI: 10.1096/fj.13-228007.Peer-Reviewed Original ResearchConceptsHuman myocardiumPreclinical modelsCardiac tissueAlternative preclinical modelsAction potential durationFrank-Starling mechanismCycle length dependenceHuman embryonic stem cell-derived cardiomyocytesDose-response curveEmbryonic stem cell-derived cardiomyocytesStem cell-derived cardiomyocytesHuman heart musclePositive chronotropicInotropic responseCardiac refractorinessCell-derived cardiomyocytesTrabecular musclesPotential durationPharmacodynamic modelMRNA expressionMyocardiumHeart muscleCardiac-specific genesTranslational researchCardiac electrophysiology
2011
Biophysical properties and functional consequences of reactive oxygen species (ROS)‐induced ROS release in intact myocardium
Biary N, Xie C, Kauffman J, Akar FG. Biophysical properties and functional consequences of reactive oxygen species (ROS)‐induced ROS release in intact myocardium. The Journal Of Physiology 2011, 589: 5167-5179. PMID: 21825030, PMCID: PMC3225672, DOI: 10.1113/jphysiol.2011.214239.Peer-Reviewed Original ResearchMeSH KeywordsAnimalsAntioxidantsArrhythmias, CardiacCyclosporineDiazepamEthidiumFluorescenceFluorescent DyesHydrogen PeroxideIn Vitro TechniquesIntracellular MembranesMitochondrial Membrane Transport ProteinsMitochondrial Permeability Transition PoreMyocardiumOrganometallic CompoundsOxidantsOxidative StressRatsSalicylatesSuperoxidesVoltage-Dependent Anion ChannelsConceptsIncidence of arrhythmiasIntact myocardiumOxidative stressMitochondrial permeability transition poreReactive oxygen speciesSustained ventricular tachycardiaROS releaseExposure of heartsGlobal oxidative stressPerfusion of heartsSuperoxide dismutase/catalase mimetic EUK-134Functional consequencesOS protocolArrhythmia scoreAcute modelDihydroethidium fluorescenceUntreated heartsVentricular tachycardiaVentricular fibrillationOxygen speciesArrhythmic consequencesElevated ROS levelsRat heartEUK-134PerfusionDisruption of Hexokinase II–Mitochondrial Binding Blocks Ischemic Preconditioning and Causes Rapid Cardiac Necrosis
Smeele KM, Southworth R, Wu R, Xie C, Nederlof R, Warley A, Nelson JK, van Horssen P, van den Wijngaard JP, Heikkinen S, Laakso M, Koeman A, Siebes M, Eerbeek O, Akar FG, Ardehali H, Hollmann MW, Zuurbier CJ. Disruption of Hexokinase II–Mitochondrial Binding Blocks Ischemic Preconditioning and Causes Rapid Cardiac Necrosis. Circulation Research 2011, 108: 1165-1169. PMID: 21527739, DOI: 10.1161/circresaha.111.244962.Peer-Reviewed Original ResearchConceptsIschemic preconditioningWild-type heartsCardiac functionProtective effectHKII levelsBaseline cardiac functionIschemia-reperfusion injuryNormal cardiac functionMitochondrial permeability transition openingContractile impairmentReperfusion injuryAcute reductionCardiac necrosisMyocardial functionGlycolytic enzymes hexokinaseCardiac contractionMild mitochondrial uncouplingMembrane depolarizationMitochondrial membrane depolarizationHKIIMitochondrial hexokinaseControl peptideHeartPreconditioningTissue disruption
2010
Ultrastructure and Regulation of Lateralized Connexin43 in the Failing Heart
Hesketh GG, Shah MH, Halperin VL, Cooke CA, Akar FG, Yen TE, Kass DA, Machamer CE, Van Eyk JE, Tomaselli GF. Ultrastructure and Regulation of Lateralized Connexin43 in the Failing Heart. Circulation Research 2010, 106: 1153-1163. PMID: 20167932, PMCID: PMC2896878, DOI: 10.1161/circresaha.108.182147.Peer-Reviewed Original ResearchMeSH KeywordsAnimalsAutophagyConnexin 43Disease Models, AnimalDogsGap JunctionsHeart FailureHeart VentriclesHeLa CellsHumansMembrane MicrodomainsMicroscopy, ConfocalMicroscopy, Electron, TransmissionMicrotubule-Associated ProteinsMyocardiumPhosphorylationRatsRats, Sprague-DawleyRecombinant Fusion ProteinsTransfectionConceptsGFP-LC3Gap junctionsLateral membranesDistinct phosphorylated formsGap junction turnoverGap junction internalizationForm of LC3Internalized gap junctionsGap junction proteinJunction turnoverSubcellular locationBiochemical regulationCellular pathwaysMultilamellar membrane structuresEndogenous Cx43Phosphorylated formNeonatal rat ventricular myocytesHeLa cellsIntracellular Cx43Membrane structureJunction proteinsCx43ProteinPotential therapeutic implicationsConnexin43Translational potential of human embryonic and induced pluripotent stem cells for myocardial repair: Insights from experimental models
Kong CW, Akar FG, Li RA. Translational potential of human embryonic and induced pluripotent stem cells for myocardial repair: Insights from experimental models. Thrombosis And Haemostasis 2010, 104: 30-38. PMID: 20539906, DOI: 10.1160/th10-03-0189.Peer-Reviewed Original Research
2008
Key pathways associated with heart failure development revealed by gene networks correlated with cardiac remodeling
Gao Z, Barth AS, DiSilvestre D, Akar FG, Tian Y, Tanskanen A, Kass DA, Winslow RL, Tomaselli GF. Key pathways associated with heart failure development revealed by gene networks correlated with cardiac remodeling. Physiological Genomics 2008, 35: 222-230. PMID: 18780759, PMCID: PMC2585017, DOI: 10.1152/physiolgenomics.00100.2007.Peer-Reviewed Original ResearchEffects of 4′-chlorodiazepam on cellular excitation–contraction coupling and ischaemia–reperfusion injury in rabbit heart
Brown DA, Aon MA, Akar FG, Liu T, Sorarrain N, O’Rourke B. Effects of 4′-chlorodiazepam on cellular excitation–contraction coupling and ischaemia–reperfusion injury in rabbit heart. Cardiovascular Research 2008, 79: 141-149. PMID: 18304929, PMCID: PMC2562874, DOI: 10.1093/cvr/cvn053.Peer-Reviewed Original ResearchConceptsIschaemia-reperfusion injuryExcitation-contraction couplingReperfusion arrhythmiasRabbit heartsDose-dependent negative inotropic responseCellular excitation-contraction couplingPost-ischemic cardiac dysfunctionOnset of reperfusionMin of reperfusionSingle bolus doseNegative inotropic responseIschaemia/reperfusionIntracellular calcium transientsSarcolemmal ion channelsIsolated rabbit cardiomyocytesIon channelsCardiac action potentialContractile impairmentCardiac dysfunctionBolus doseContractile dysfunctionInotropic responseGlobal ischaemiaVoltage clamp methodCalcium current
2005
The mitochondrial origin of postischemic arrhythmias
Akar FG, Aon MA, Tomaselli GF, O'Rourke B. The mitochondrial origin of postischemic arrhythmias. Journal Of Clinical Investigation 2005, 115: 3527-3535. PMID: 16284648, PMCID: PMC1280968, DOI: 10.1172/jci25371.Peer-Reviewed Original ResearchMeSH KeywordsAction PotentialsAnimalsAnionsArrhythmias, CardiacDose-Response Relationship, DrugElectrophysiologyGuinea PigsHeartIntracellular MembranesIon ChannelsIschemiaMembrane PotentialsMicroscopy, ConfocalMitochondria, HeartMyocardial IschemiaMyocardial ReperfusionMyocardial Reperfusion InjuryMyocardiumMyocytes, CardiacOscillometryReactive Oxygen SpeciesReceptors, GABA-AReperfusion InjuryTemperatureTime FactorsConceptsAction potentialsVentricular fibrillationPostischemic functional recoveryIschemic heart diseaseGuinea pig heartsNew therapeutic targetsAbnormal electrical activationPostischemic arrhythmiasReperfusion arrhythmiasFunctional recoveryGlobal ischemiaHeart diseaseBolus infusionArrhythmia preventionElectrophysiological changesAP shorteningControl heartsPostischemic heartsBenzodiazepine receptorsElectrophysiological substrateTherapeutic targetArrhythmiasReperfusionPig heartsMitochondrial benzodiazepine receptor
2004
Mechanisms Underlying Conduction Slowing and Arrhythmogenesis in Nonischemic Dilated Cardiomyopathy
Akar FG, Spragg DD, Tunin RS, Kass DA, Tomaselli GF. Mechanisms Underlying Conduction Slowing and Arrhythmogenesis in Nonischemic Dilated Cardiomyopathy. Circulation Research 2004, 95: 717-725. PMID: 15345654, DOI: 10.1161/01.res.0000144125.61927.1c.Peer-Reviewed Original ResearchMeSH KeywordsAction PotentialsAnimalsArrhythmias, CardiacBlotting, WesternCadherinsCardiac Pacing, ArtificialCardiomyopathy, DilatedCell SizeConnexin 43DogsFibrosisGap JunctionsHeart Conduction SystemMicroscopy, ConfocalMicroscopy, FluorescenceMyocardiumMyocytes, CardiacNeural ConductionPatch-Clamp TechniquesPhosphorylationProtein Processing, Post-TranslationalSubcellular FractionsHeterogeneous connexin43 expression produces electrophysiological heterogeneities across ventricular wall
Poelzing S, Akar FG, Baron E, Rosenbaum DS. Heterogeneous connexin43 expression produces electrophysiological heterogeneities across ventricular wall. AJP Heart And Circulatory Physiology 2004, 286: h2001-h2009. PMID: 14704225, DOI: 10.1152/ajpheart.00987.2003.Peer-Reviewed Original Research
2002
Unique Topographical Distribution of M Cells Underlies Reentrant Mechanism of Torsade de Pointes in the Long-QT Syndrome
Akar FG, Yan GX, Antzelevitch C, Rosenbaum DS. Unique Topographical Distribution of M Cells Underlies Reentrant Mechanism of Torsade de Pointes in the Long-QT Syndrome. Circulation 2002, 105: 1247-1253. PMID: 11889021, DOI: 10.1161/hc1002.105231.Peer-Reviewed Original ResearchConceptsLong QT syndromeSpecific ion channel mutationsCongenital long QT syndromeM cellsQT interval prolongationIon channel mutationsInterval prolongationReentrant mechanismTdP arrhythmiasConduction blockCanine wedge preparationReentrant circuitTransmural dispersionLeft ventricleAction potentialsTransmural wallIntact myocardiumTopographical distributionChannel mutationsWedge preparationsMidmyocardial cellsRepolarizationLQT2Cellular basisElectrical instability
2001
Optical measurement of cell-to-cell coupling in intact heart using subthreshold electrical stimulation
Akar F, Roth B, Rosenbaum D. Optical measurement of cell-to-cell coupling in intact heart using subthreshold electrical stimulation. AJP Heart And Circulatory Physiology 2001, 281: h533-h542. PMID: 11454554, DOI: 10.1152/ajpheart.2001.281.2.h533.Peer-Reviewed Original Research
2000
Cellular basis for dispersion of repolarization underlying reentrant arrhythmias
Akar F, Laurita K, Rosenbaum D. Cellular basis for dispersion of repolarization underlying reentrant arrhythmias. Journal Of Electrocardiology 2000, 33: 23-31. PMID: 11265727, DOI: 10.1054/jelc.2000.20313.Peer-Reviewed Original Research