Developmental epileptic encephalopathy associated with the CACNA1E gene mutation / 中华实用儿科临床杂志

One of the important causes of developmental epileptic encephalopathy (DEE) is the mutation of ion channel genes, including the mutation of the CACNA1E gene. CACNA1E-related DEE cases were first reported in 2018.The mutation types include new missense mutations, nonsense mutations and frameshift mutations, but the correlation between mutation sites and types with the phenotype of DEE is not clear.This review aims to summarize the reported CACNA1E-related DEE cases, and explore the correlation between the clinical phenotype of CACNA1E-related DEE and gene mutation sites and mutation types.Meanwhile, possible pathogenesis of CACNA1E-related DEE and the progress of drug intervention were reviewed to provide references for the diagnosis and precise treatment of DEE.

R-type Calcium Channel Isoform in Rat Dorsal Root Ganglion Neurons

R-type Cav2.3 high voltage-activated Ca2+ channels in peripheral sensory neurons contribute to pain transmission. Recently we have demonstrated that, among the six Cav2.3 isoforms (Cav2.3a~Cav2.3e), the Cav2.3e isoform is primarily expressed in trigeminal ganglion (TG) nociceptive neurons. In the present study, we further investigated expression patterns of Cav2.3 isoforms in the dorsal root ganglion (DRG) neurons. As in TG neurons, whole tissue RT-PCR analyses revealed the presence of two isoforms, Cav2.3a and Cav2.3e, in DRG neurons. Single-cell RT-PCR detected the expression of Cav2.3e mRNA in 20% (n=14/70) of DRG neurons, relative to Cav2.3a expression in 2.8% (n=2/70) of DRG neurons. Cav2.3e mRNA was mainly detected in small-sized neurons (n=12/14), but in only a few medium-sized neurons (n=2/14) and not in large-sized neurons, indicating the prominence of Cav2.3e in nociceptive DRG neurons. Moreover, Cav2.3e was preferentially expressed in tyrosine-kinase A (trkA)-positive, isolectin B4 (IB4)-negative and transient receptor potential vanilloid 1 (TRPV1)-positive neurons. These results suggest that Cav2.3e may be the main R-type Ca2+ channel isoform in nociceptive DRG neurons and thereby a potential target for pain treatment, not only in the trigeminal system but also in the spinal system.

Ca_V 2.3 voltage-gated calcium channel and epilepsy / 中国病理生理杂志

The CaV 2.3 encoded Ca2+ channel is one of the least well-known voltage-gated calcium channels in terms of physiology, pharmacology and clinical relevance. Epilepsy is a family of neurological disorders that are common and harmful to human health. More and more studies such as gene knock-out experiment have demonstrated that the channel is related to epileptic seizure, including participating to plateau potential generation, regulating intracellular Ca2+ concentration, CaV 2.3 splice variant, interacting with some muteins. In addition, some antiepileptic drugs inhibit the epileptiform discharges by targeting CaV 2.3 voltage-gated calcium channel.