2022
Humanized Dsp ACM Mouse Model Displays Stress-Induced Cardiac Electrical and Structural Phenotypes
Stevens TL, Manring HR, Wallace MJ, Argall A, Dew T, Papaioannou P, Antwi-Boasiako S, Xu X, Campbell SG, Akar FG, Borzok MA, Hund TJ, Mohler PJ, Koenig SN, El Refaey M. Humanized Dsp ACM Mouse Model Displays Stress-Induced Cardiac Electrical and Structural Phenotypes. Cells 2022, 11: 3049. PMID: 36231013, PMCID: PMC9562631, DOI: 10.3390/cells11193049.Peer-Reviewed Original ResearchConceptsArrhythmogenic cardiomyopathyMouse modelStructural phenotypesFibro-fatty infiltrationFirst mouse modelHeart failureChamber dilationVentricular arrhythmiasPressure overloadArrhythmic eventsCardiac performanceCardiac stressSudden deathCardiovascular stressInherited disorderG variantConnexin 43MiceDesmosomal genesReduced expressionExternal stressorsACM familyDisease developmentMurine equivalentIncomplete penetranceAtrial AMP-activated protein kinase is critical for prevention of dysregulation of electrical excitability and atrial fibrillation
Su KN, Ma Y, Cacheux M, Ilkan Z, Raad N, Muller GK, Wu X, Guerrera N, Thorn SL, Sinusas AJ, Foretz M, Viollet B, Akar JG, Akar FG, Young LH. Atrial AMP-activated protein kinase is critical for prevention of dysregulation of electrical excitability and atrial fibrillation. JCI Insight 2022, 7: e141213. PMID: 35451373, PMCID: PMC9089788, DOI: 10.1172/jci.insight.141213.Peer-Reviewed Original ResearchConceptsTranscription factorsKey transcription factorMaster metabolic regulatorIon channel subunitsGap junction proteinTranscriptional reprogrammingAMPK deletionProtein kinaseBiological functionsTranscriptional downregulationMetabolic regulatorChannel subunitsIon channelsAMPK expressionMetabolic stressAtrial fibrillationAMPKJunction proteinsElectrical excitabilityHomeostatic roleStructural remodelingConnexinsAtrial ion channelsRemodelingDownregulationGene editing reverses arrhythmia susceptibility in humanized PLN-R14del mice: modelling a European cardiomyopathy with global impact
Dave J, Raad N, Mittal N, Zhang L, Fargnoli A, Oh JG, Savoia ME, Hansen J, Fava M, Yin X, Theofilatos K, Ceholski D, Kohlbrenner E, Jeong D, Wills L, Nonnenmacher M, Haghighi K, Costa KD, Turnbull IC, Mayr M, Cai CL, Kranias EG, Akar FG, Hajjar RJ, Stillitano F. Gene editing reverses arrhythmia susceptibility in humanized PLN-R14del mice: modelling a European cardiomyopathy with global impact. Cardiovascular Research 2022, 118: 3140-3150. PMID: 35191471, PMCID: PMC9732517, DOI: 10.1093/cvr/cvac021.Peer-Reviewed Original ResearchConceptsAdeno-associated virus 9Ventricular tachycardiaCardiac functionStroke volumeHigh arrhythmia burdenSustained ventricular tachycardiaSudden cardiac deathCardiac magnetic resonancePre-symptomatic carriersYoung adult miceWeeks of ageDroplet digital polymerase chain reactionArrhythmia burdenVulnerable myocardiumCardiac deathEjection fractionPreclinical evidenceMalignant arrhythmiasVentricular dilationHumanized miceWT miceCardiac outputPolymerase chain reactionPLN-R14DelAdult mice
2021
Arrhythmia Mechanism and Dynamics in a Humanized Mouse Model of Inherited Cardiomyopathy Caused by Phospholamban R14del Mutation
Raad N, Bittihn P, Cacheux M, Jeong D, Ilkan Z, Ceholski D, Kohlbrenner E, Zhang L, Cai CL, Kranias EG, Hajjar RJ, Stillitano F, Akar FG. Arrhythmia Mechanism and Dynamics in a Humanized Mouse Model of Inherited Cardiomyopathy Caused by Phospholamban R14del Mutation. Circulation 2021, 144: 441-454. PMID: 34024116, PMCID: PMC8456417, DOI: 10.1161/circulationaha.119.043502.Peer-Reviewed Original ResearchConceptsHuman PLNRapid pacingInterventricular activation delayHumanized mouse modelAction potential prolongationLocal conduction blockSteep repolarization gradientsArrhythmogenic featuresMacroreentrant circuitHemodynamic changesElectric remodelingElectrophysiological remodelingRight ventricleVentricular tachycardiaPotential prolongationSudden deathConduction blockMouse modelAdult knockArrhythmia susceptibilityAdrenergic stimulationStructural remodelingArrhythmogenic phenotypeArrhythmia mechanismsRegulatory protein phospholamban
2019
Cardiomyocyte-Specific STIM1 (Stromal Interaction Molecule 1) Depletion in the Adult Heart Promotes the Development of Arrhythmogenic Discordant Alternans
Cacheux M, Strauss B, Raad N, Ilkan Z, Hu J, Benard L, Feske S, Hulot JS, Akar FG. Cardiomyocyte-Specific STIM1 (Stromal Interaction Molecule 1) Depletion in the Adult Heart Promotes the Development of Arrhythmogenic Discordant Alternans. Circulation Arrhythmia And Electrophysiology 2019, 12: e007382-e007382. PMID: 31726860, PMCID: PMC6867678, DOI: 10.1161/circep.119.007382.Peer-Reviewed Original ResearchConceptsVT/VFAPD alternansStore-operated CaVentricular tachycardia/ventricular fibrillationOptical action potential mappingAdult heartVT/Adult murine modelDiscordant alternansConduction velocity slowingSarcoplasmic reticulum CaArrhythmogenic discordant alternansInitial beatsEarly mortalityFlox/Poor survivalVentricular fibrillationDiscordant APD alternansMurine modelCardiac hypertrophyConduction velocityLittermate controlsAdult miceRapid pacingElectrophysiological substrate
2015
LKB1 deletion causes early changes in atrial channel expression and electrophysiology prior to atrial fibrillation
Kim GE, Ross JL, Xie C, Su KN, Zaha VG, Wu X, Palmeri M, Ashraf M, Akar JG, Russell KS, Akar FG, Young LH. LKB1 deletion causes early changes in atrial channel expression and electrophysiology prior to atrial fibrillation. Cardiovascular Research 2015, 108: 197-208. PMID: 26378152, PMCID: PMC4571838, DOI: 10.1093/cvr/cvv212.Peer-Reviewed Original ResearchConceptsLiver kinase B1Protein kinaseLKB1 deletionMetabolic regulator AMPAtrial fibrillationChannel expressionMHC-CreElectrophysiological functionKnockout mouse modelRelated kinasesLKB1 pathwayGene expressionPerpetuation of AFKinase B1Neonatal atrial myocytesΑMHC-CreKinasePostnatal day 1Patch-clamp recordingsAtrial growthWeeks of ageDeletionSodium current densityAction potential generationSpecific role
2012
GSH or Palmitate Preserves Mitochondrial Energetic/Redox Balance, Preventing Mechanical Dysfunction in Metabolically Challenged Myocytes/Hearts From Type 2 Diabetic Mice
Tocchetti CG, Caceres V, Stanley BA, Xie C, Shi S, Watson WH, O’Rourke B, Spadari-Bratfisch RC, Cortassa S, Akar FG, Paolocci N, Aon MA. GSH or Palmitate Preserves Mitochondrial Energetic/Redox Balance, Preventing Mechanical Dysfunction in Metabolically Challenged Myocytes/Hearts From Type 2 Diabetic Mice. Diabetes 2012, 61: 3094-3105. PMID: 22807033, PMCID: PMC3501888, DOI: 10.2337/db12-0072.Peer-Reviewed Original ResearchConceptsMechanical dysfunctionReactive oxygen speciesType 2 diabetic db/db miceDiabetic db/db miceHigh glucoseType 2 diabetic patientsType 2 diabetic miceDb/db miceLower cardiac performanceLimited exercise capacityPoor glycemic controlType 2 diabetesΒ-agonist isoproterenolCardiac work demandsFatty acid palmitateExercise capacitySympathetic driveGlycemic controlDiabetic patientsDiabetic miceDb miceHeart dysfunctionPatient's inabilityMitochondrial reactive oxygen speciesHeart preparation
2011
Disruption 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
2008
Targeted deletion of kcne2 impairs ventricular repolarization via disruption of IK,slow1 and Ito,f
Roepke TK, Kontogeorgis A, Ovanez C, Xu X, Young JB, Purtell K, Goldstein PA, Christini DJ, Peters NS, Akar FG, Gutstein DE, Lerner DJ, Abbott GW. Targeted deletion of kcne2 impairs ventricular repolarization via disruption of IK,slow1 and Ito,f. The FASEB Journal 2008, 22: 3648-3660. PMID: 18603586, PMCID: PMC2537427, DOI: 10.1096/fj.08-110171.Peer-Reviewed Original ResearchConceptsAlpha subunitKv4 alpha subunitsAction potential durationVentricular action potential durationFunctional promiscuityVentricular membrane fractionsLong QT syndromeVentricular repolarizationAncillary subunitsWild typeNovel roleMembrane fractionKcne2 deletionKv1.5 proteinTargeted deletionSubunitsKcne2 disruptionMiRP1Cardiac roleProteinKCNE2DeletionKv1.5Sevoflurane anesthesiaDisruption
2006
Bioartificial Sinus Node Constructed via In Vivo Gene Transfer of an Engineered Pacemaker HCN Channel Reduces the Dependence on Electronic Pacemaker in a Sick-Sinus Syndrome Model
Tse HF, Xue T, Lau CP, Siu CW, Wang K, Zhang QY, Tomaselli GF, Akar FG, Li RA. Bioartificial Sinus Node Constructed via In Vivo Gene Transfer of an Engineered Pacemaker HCN Channel Reduces the Dependence on Electronic Pacemaker in a Sick-Sinus Syndrome Model. Circulation 2006, 114: 1000-1011. PMID: 16923751, DOI: 10.1161/circulationaha.106.615385.Peer-Reviewed Original ResearchAnimalsArrhythmias, CardiacBioartificial OrgansCyclic Nucleotide-Gated Cation ChannelsDisease Models, AnimalElectrophysiologyGene Transfer TechniquesGuinea PigsHeart RateHyperpolarization-Activated Cyclic Nucleotide-Gated ChannelsIon ChannelsMicePacemaker, ArtificialPotassium ChannelsSick Sinus SyndromeSinoatrial NodeSwineSwine, Miniature
2004
Functional Integration of Electrically Active Cardiac Derivatives From Genetically Engineered Human Embryonic Stem Cells With Quiescent Recipient Ventricular Cardiomyocytes
Xue T, Cho HC, Akar FG, Tsang SY, Jones SP, Marbán E, Tomaselli GF, Li RA. Functional Integration of Electrically Active Cardiac Derivatives From Genetically Engineered Human Embryonic Stem Cells With Quiescent Recipient Ventricular Cardiomyocytes. Circulation 2004, 111: 11-20. PMID: 15611367, DOI: 10.1161/01.cir.0000151313.18547.a2.Peer-Reviewed Original ResearchMeSH KeywordsAction PotentialsAdrenergic beta-AgonistsAnimalsCell DifferentiationCell FusionCells, CulturedDefective VirusesElectrophysiologyFemaleGenes, ReporterGenetic VectorsGiant CellsGreen Fluorescent ProteinsGuinea PigsHeartHeart Conduction SystemHeart VentriclesHIV-1HumansIsoproterenolLidocaineMiceMyocardial ContractionMyocytes, CardiacOrgan Culture TechniquesPericardiumPluripotent Stem CellsPyrimidinesRatsTransduction, GeneticConceptsVentricular cardiomyocytesCardiac impulse generationBeta-adrenergic agonist isoproterenolGuinea pig heartsSite of injectionStem cellsHuman embryonic stem cellsCell-based therapiesContractile activityAgonist isoproterenolPharmacological agentsVentricular myocardiumLeft ventricleEx vivoDonor cardiomyocytesPig heartsHuman cardiomyocytesRecombinant lentivirusMembrane depolarizationCardiomyocytesFunctional syncytiumImpulse generationEmbryonic stem cellsMyocardiumEpicardial surface