Reduced Expression of Voltage-Gated Sodium Channel Beta 2 Restores Neuronal Injury and Improves Cognitive Dysfunction Induced by Aß1-42.

ABSTRACT

Voltage-gated sodium channel beta 2 (Nav2.2 or Navß2, coded by SCN2B mRNA), a gene involved in maintaining normal physiological functions of the prefrontal cortex and hippocampus, might be associated with prefrontal cortex aging and memory decline. This study investigated the effects of Navß2 in amyloid-ß 1-42- (Aß1-42-) induced neural injury model and the potential underlying molecular mechanism. The results showed that Navß2 knockdown restored neuronal viability of Aß1-42-induced injury in neurons; increased the contents of brain-derived neurotrophic factor (BDNF), enzyme neprilysin (NEP) protein, and NEP enzyme activity; and effectively altered the proportions of the amyloid precursor protein (APP) metabolites including Aß42, sAPPα, and sAPPß, thus ameliorating cognitive dysfunction. This may be achieved through regulating NEP transcription and APP metabolism, accelerating Aß degradation, alleviating neuronal impairment, and regulating BDNF-related signal pathways to repair neuronal synaptic efficiency. This study provides novel evidence indicating that Navß2 plays crucial roles in the repair of neuronal injury induced by Aß1-42 both in vivo and in vitro.