2016
A painful neuropathy-associated Nav1.7 mutant leads to time-dependent degeneration of small-diameter axons associated with intracellular Ca2+ dysregulation and decrease in ATP levels
Rolyan H, Liu S, Hoeijmakers JG, Faber CG, Merkies IS, Lauria G, Black JA, Waxman SG. A painful neuropathy-associated Nav1.7 mutant leads to time-dependent degeneration of small-diameter axons associated with intracellular Ca2+ dysregulation and decrease in ATP levels. Molecular Pain 2016, 12: 1744806916674472. PMID: 27821467, PMCID: PMC5102167, DOI: 10.1177/1744806916674472.Peer-Reviewed Original ResearchConceptsSmall fiber neuropathySmall-diameter axonsTime-dependent degenerationDorsal root ganglion neuronsNerve fiber injuryNervous system disordersPrevious clinical reportsIntracellular calcium levelsMutant Nav1.7 channelsATP levelsAδ nerve fibersHigh altitude sicknessPainful neuropathyTime-dependent increaseFiber injuryClinical onsetGanglion neuronsOxygen species productionSystem disordersCalcium levelsClinical reportsDistal extremitiesIntracellular Ca2NeuropathyNav1.7 channels
2015
Ca2+ toxicity due to reverse Na+/Ca2+ exchange contributes to degeneration of neurites of DRG neurons induced by a neuropathy-associated Nav1.7 mutation
Estacion M, Vohra BP, Liu S, Hoeijmakers J, Faber CG, Merkies IS, Lauria G, Black JA, Waxman SG. Ca2+ toxicity due to reverse Na+/Ca2+ exchange contributes to degeneration of neurites of DRG neurons induced by a neuropathy-associated Nav1.7 mutation. Journal Of Neurophysiology 2015, 114: 1554-1564. PMID: 26156380, PMCID: PMC4561630, DOI: 10.1152/jn.00195.2015.Peer-Reviewed Original ResearchConceptsSmall fiber neuropathyDRG neuronsNav1.7 mutationCell bodiesDorsal root ganglion neuronsDRG cell bodiesModes of NCXIntraepidermal nerve fibersVoltage-gated sodium channel Nav1.7Sodium/calcium exchangerDegeneration of neuritesSodium channel Nav1.7Levels of intracellularTreatment of WTAxonal degenerationGanglion neuronsFunction missense mutationsNerve fibersAxon degenerationChannel Nav1.7Reverse NCXCalcium exchangerNav1.7DegenerationNeurons
2012
Neuropathy‐associated NaV1.7 variant I228M impairs integrity of dorsal root ganglion neuron axons
Persson A, Liu S, Faber CG, Merkies IS, Black JA, Waxman SG. Neuropathy‐associated NaV1.7 variant I228M impairs integrity of dorsal root ganglion neuron axons. Annals Of Neurology 2012, 73: 140-145. PMID: 23280954, DOI: 10.1002/ana.23725.Peer-Reviewed Original ResearchConceptsSmall fiber neuropathyIntraepidermal nerve fibersIdiopathic small fiber neuropathyNa-Ca exchangeDRG neuronsNeurite lengthSensory axonsLoss of IENFsReverse Na-Ca exchangeDorsal root ganglion neuronsPeripheral sensory axonsPeripheral nerve axonsSodium channel blockers carbamazepineSodium channel activityAxonal degenerationGanglion neuronsSpontaneous firingNerve fibersAxonal integrityNeuron axonsImpaired regenerationNerve axonsFunction variantsAxonsSodium channelsFunctional profiles of SCN9A variants in dorsal root ganglion neurons and superior cervical ganglion neurons correlate with autonomic symptoms in small fibre neuropathy
Han C, Hoeijmakers JG, Liu S, Gerrits MM, Morsche R, Lauria G, Dib-Hajj SD, Drenth JP, Faber CG, Merkies IS, Waxman SG. Functional profiles of SCN9A variants in dorsal root ganglion neurons and superior cervical ganglion neurons correlate with autonomic symptoms in small fibre neuropathy. Brain 2012, 135: 2613-2628. PMID: 22826602, DOI: 10.1093/brain/aws187.Peer-Reviewed Original ResearchConceptsDorsal root ganglion neuronsSevere autonomic dysfunctionSmall fiber neuropathySuperior cervical ganglion neuronsSympathetic ganglion neuronsAutonomic dysfunctionGanglion neuronsDorsal root gangliaAutonomic symptomsRoot gangliaSmall-diameter peripheral axonsSensory dorsal root gangliaSuperior cervical ganglionPeripheral nervous systemChannel slow inactivationDetectable changeNeuropathic painSCN9A geneCervical ganglionSympathetic neuronsPeripheral axonsNeuropathyPatientsDistal extremitiesNervous system