Limitations of Current GABA Agonists in Neonatal Seizures: Toward GABA Modulation Via the Targeting of Neuronal Cl(-) Transport

Front Neurol. 2013 Jun 25;4:78. doi: 10.3389/fneur.2013.00078. eCollection 2013.

Abstract

Neonatal intensive care has advanced rapidly in the last 40 years, with dramatic decreases in mortality and morbidity; however, for neonatal seizures, neither therapies nor outcomes have changed significantly. Basic and clinical studies indicate that seizures in neonates have long-term neurodevelopmental and psychiatric consequences, highlighting the need for novel pharmacotherapeutics. First-line treatments targeting GABAA receptors, like barbiturates and benzodiazepines, are limited in their efficacy and carry significant risks to the developing brain. Here, we review the use of current GABA agonist therapies for neonatal seizures and suggest other treatment strategies given recent developments in the understanding of disease pathogenesis. One promising avenue is the indirect manipulation of the GABAergic system, via the modulation of neuronal Cl(-) gradients, by targeting the cation-Cl(-) cotransporters (NKCC1 and KCC2) or their regulatory signaling molecules. This strategy might yield a novel class of more efficacious anti-epileptics with fewer side effects by specifically addressing disease pathophysiology. Moreover, this strategy may have ramifications for other adult seizure syndromes in which GABA receptor-mediated depolarizations play a pathogenic role, such as temporal lobe epilepsy.

Keywords: GABA; KCC2; NKCC1; SPAK/OSR1 kinase; WNK kinase; bumetanide; neonatal seizure; seizure.