2024
Interplay of Nav1.8 and Nav1.7 channels drives neuronal hyperexcitability in neuropathic pain
Vasylyev D, Zhao P, Schulman B, Waxman S. Interplay of Nav1.8 and Nav1.7 channels drives neuronal hyperexcitability in neuropathic pain. The Journal Of General Physiology 2024, 156: e202413596. PMID: 39378238, PMCID: PMC11465073, DOI: 10.1085/jgp.202413596.Peer-Reviewed Original ResearchConceptsDorsal root ganglionGain-of-function Nav1.7 mutationsDorsal root ganglion neuronsSodium channel Nav1.7Inherited erythromelalgiaNav1.7 mutationsNeuropathic painNeuronal hyperexcitabilityOpen-probabilityVoltage-gated sodium channel Nav1.7Hyperexcitability of DRG neuronsModel of neuropathic painSubthreshold membrane potential oscillationsResting membrane potentialMembrane potential oscillationsReduced firing probabilityIncreased rheobaseNav1.8 channelsDRG neuronsHuman genetic modelsNav1.8Root ganglionNav1.7 channelsNav1.7AP generation
2022
Fibroblast growth factor homologous factor 2 attenuates excitability of DRG neurons
Effraim PR, Estacion M, Zhao P, Sosniak D, Waxman SG, Dib-Hajj SD. Fibroblast growth factor homologous factor 2 attenuates excitability of DRG neurons. Journal Of Neurophysiology 2022, 128: 1258-1266. PMID: 36222860, PMCID: PMC9909838, DOI: 10.1152/jn.00361.2022.Peer-Reviewed Original ResearchConceptsDRG neuron excitabilityDRG neuronal excitabilityNeuronal excitabilityFibroblast growth factor homologous factorsNerve injuryDRG neuronsInflammatory mediatorsNeuron excitabilityDorsal root ganglion neuronsFunction of Nav1.7Peripheral nerve axotomyMultiple neurological disordersVoltage-gated sodium channelsDRG excitabilityFibroblast growth factor homologous factor 2Inflammatory painNerve axotomyGanglion neuronsIsoform-dependent mannerNeurological disordersBasal conditionsExcitabilityGating propertiesNeuron firingInjury
2021
Contributions of NaV1.8 and NaV1.9 to excitability in human induced pluripotent stem-cell derived somatosensory neurons
Alsaloum M, Labau JIR, Liu S, Estacion M, Zhao P, Dib-Hajj F, Waxman SG. Contributions of NaV1.8 and NaV1.9 to excitability in human induced pluripotent stem-cell derived somatosensory neurons. Scientific Reports 2021, 11: 24283. PMID: 34930944, PMCID: PMC8688473, DOI: 10.1038/s41598-021-03608-x.Peer-Reviewed Original ResearchMeSH KeywordsAction PotentialsAutopsyCell DifferentiationElectrophysiologyHumansImmunohistochemistryInduced Pluripotent Stem CellsMembrane PotentialsMutationNAV1.8 Voltage-Gated Sodium ChannelNAV1.9 Voltage-Gated Sodium ChannelNeuronsNeurosciencesPainPatch-Clamp TechniquesProtein IsoformsSensory Receptor CellsSomatosensory CortexConceptsNeuronal excitabilitySomatosensory neuronsPluripotent stem cell-derived sensory neuronsDynamic clamp electrophysiologyTreatment of painPromising novel modalityVoltage-gated sodium channelsSodium channel isoformsNeuronal membrane potentialGenetic knockout modelsNav1.9 currentsPharmacologic blockSensory neuronsNav1.8Cellular correlatesRepetitive firingClamp electrophysiologyExcitabilityNeuronal backgroundNovel modalityChannel isoformsSodium channelsNeuronsNav1.9Knockout models
2014
Dynamic-clamp analysis of wild-type human Nav1.7 and erythromelalgia mutant channel L858H
Vasylyev DV, Han C, Zhao P, Dib-Hajj S, Waxman SG. Dynamic-clamp analysis of wild-type human Nav1.7 and erythromelalgia mutant channel L858H. Journal Of Neurophysiology 2014, 111: 1429-1443. PMID: 24401712, DOI: 10.1152/jn.00763.2013.Peer-Reviewed Original ResearchMeSH KeywordsAnimalsBiophysicsCells, CulturedElectric StimulationErythromelalgiaGanglia, SpinalHEK293 CellsHumansMembrane PotentialsMiceMice, KnockoutModels, BiologicalMutationNAV1.7 Voltage-Gated Sodium ChannelNeural ConductionNeuronsPatch-Clamp TechniquesSodium Channel BlockersTetrodotoxinTransfectionConceptsDRG neuronsMutant Nav1.7 channelsNav1.7 channelsDorsal root ganglion neuronsSodium influxPrimary nociceptive neuronsSmall DRG neuronsNet sodium influxSodium channel Nav1.7Current thresholdMechanistic linkAction potential generationNeuropathic painNociceptive neuronsNociceptor functionGanglion neuronsNociceptor hyperexcitabilityPain phenotypesChannel expressionChannel Nav1.7Subthreshold depolarizationHuman Nav1.7Electrophysiological recordingsDynamic-Clamp AnalysisIdentification of gain
2013
Sodium Channels Contribute to Degeneration of Dorsal Root Ganglion Neurites Induced by Mitochondrial Dysfunction in an In Vitro Model of Axonal Injury
Persson AK, Kim I, Zhao P, Estacion M, Black JA, Waxman SG. Sodium Channels Contribute to Degeneration of Dorsal Root Ganglion Neurites Induced by Mitochondrial Dysfunction in an In Vitro Model of Axonal Injury. Journal Of Neuroscience 2013, 33: 19250-19261. PMID: 24305821, PMCID: PMC6618782, DOI: 10.1523/jneurosci.2148-13.2013.Peer-Reviewed Original ResearchMeSH KeywordsAnimalsAxonsAxotomyCell DeathCells, CulturedGanglia, SpinalHumansHydrogen PeroxideImmunohistochemistryMiceMice, TransgenicMicrotubulesMitochondrial DiseasesNerve DegenerationNeuritesOxidantsRotenoneSodium Channel BlockersSodium ChannelsSodium-Calcium ExchangerSodium-Potassium-Exchanging ATPaseTetrodotoxinThioureaUncoupling AgentsConceptsAxonal degenerationNeurite degenerationSodium channelsKB-R7943Mouse peripheral sensory neuronsRotenone-induced mitochondrial dysfunctionOxidative stressMitochondrial dysfunctionPeripheral sensory neuronsDorsal root gangliaPeripheral nervous systemDegeneration of neuritesMitochondrial functionVoltage-gated sodium channelsMultiple neurodegenerative disordersSodium-calcium exchangerImpaired mitochondrial functionInjurious cascadeAxonal injuryActivity blockadeRoot gangliaAxonal neuropathySensory neuronsNCX activityDysfunctional intracellularSmall-Fiber Neuropathy Nav1.8 Mutation Shifts Activation to Hyperpolarized Potentials and Increases Excitability of Dorsal Root Ganglion Neurons
Huang J, Yang Y, Zhao P, Gerrits MM, Hoeijmakers JG, Bekelaar K, Merkies IS, Faber CG, Dib-Hajj SD, Waxman SG. Small-Fiber Neuropathy Nav1.8 Mutation Shifts Activation to Hyperpolarized Potentials and Increases Excitability of Dorsal Root Ganglion Neurons. Journal Of Neuroscience 2013, 33: 14087-14097. PMID: 23986244, PMCID: PMC6618513, DOI: 10.1523/jneurosci.2710-13.2013.Peer-Reviewed Original ResearchMeSH KeywordsAction PotentialsAmino Acid SequenceAnimalsCells, CulturedGanglia, SpinalHumansIon Channel GatingMaleMembrane PotentialsMiceMice, TransgenicMiddle AgedMolecular Sequence DataMutation, MissenseNAV1.8 Voltage-Gated Sodium ChannelNeuronsPeripheral Nervous System DiseasesRatsRats, Sprague-DawleyConceptsDorsal root ganglion neuronsSmall DRG neuronsDRG neuronsGanglion neuronsAction potentialsIdiopathic small fiber neuropathySmall-diameter DRG neuronsWhole-cell voltage-clamp recordingsSmall-caliber nerve fibersVoltage-gated sodium channel Nav1.7Peripheral sensory neuronsCurrent-clamp studiesLimited treatment optionsSmall fiber neuropathySodium channel Nav1.8Voltage-clamp recordingsSodium channel Nav1.7Autonomic dysfunctionIncreases excitabilityTreatment optionsUnknown etiologyFunctional variantsNerve fibersSensory neuronsRamp depolarization
2012
Nav1.7-related small fiber neuropathy
Han C, Hoeijmakers JG, Ahn H, Zhao P, Shah P, Lauria G, Gerrits MM, te Morsche R, Dib-Hajj SD, Drenth JP, Faber CG, Merkies IS, Waxman SG. Nav1.7-related small fiber neuropathy. Neurology 2012, 78: 1635-1643. PMID: 22539570, DOI: 10.1212/wnl.0b013e3182574f12.Peer-Reviewed Original ResearchConceptsSmall fiber neuropathyDorsal root gangliaDRG neuronsIdiopathic small fiber neuropathySmall-diameter peripheral axonsDRG neuron hyperexcitabilityIdentifiable underlying causeNerve conduction studiesQuantitative sensory testingSympathetic ganglion neuronsSFN symptomsNeuron hyperexcitabilityConduction studiesGanglion neuronsRoot gangliaSkin biopsiesDifferential diagnosisPeripheral axonsSensory testingVoltage-clamp analysisApparent causePatientsNoninactivating componentUnderlying causeSuprathreshold stimuli
2009
BDNF-Hypersecreting Human Mesenchymal Stem Cells Promote Functional Recovery, Axonal Sprouting, and Protection of Corticospinal Neurons after Spinal Cord Injury
Sasaki M, Radtke C, Tan AM, Zhao P, Hamada H, Houkin K, Honmou O, Kocsis JD. BDNF-Hypersecreting Human Mesenchymal Stem Cells Promote Functional Recovery, Axonal Sprouting, and Protection of Corticospinal Neurons after Spinal Cord Injury. Journal Of Neuroscience 2009, 29: 14932-14941. PMID: 19940189, PMCID: PMC2825276, DOI: 10.1523/jneurosci.2769-09.2009.Peer-Reviewed Original ResearchMeSH KeywordsAnimalsBrain-Derived Neurotrophic FactorCells, CulturedCytoprotectionDisease Models, AnimalFemaleGene ExpressionGenetic VectorsGrowth ConesHumansMesenchymal Stem Cell TransplantationNerve RegenerationNeuronal PlasticityPyramidal TractsRatsRats, Sprague-DawleyRecovery of FunctionSpinal Cord InjuriesTransfectionTransplantation, HeterologousTreatment OutcomeConceptsSpinal cord injuryMesenchymal stem cellsCord injuryFunctional outcomeBone marrowAcute spinal cord injuryBrain-derived neurotrophic factorCorticospinal tract neuronsNumber of FGImproved functional outcomesPrimary motor cortexSpinal gray matterPotential therapeutic effectsStem cellsM1 cortexTransection lesionCorticospinal neuronsTract neuronsAxonal sproutingFunctional recoveryVentral hornNeuronal densitySerotonergic fibersLesion cavityMotor cortex