Current review on inducible nitric oxide synthase and Src tyrosine kinase inhibitors as disease-modifiers in preclinical models of epilepsy.

Abstract

Acute exposure to seizurogenic chemicals, such as organophosphates (OPs) or domoic acid (kainate analogue), can trigger status epilepticus (SE), marked by central (seizures) and, with OPs, peripheral effects due to irreversible inhibition of acetylcholinesterase (AChE). The initial seizurogenic activity in the brain initiates a cascade of molecular and cellular changes, known as epileptogenesis, the process by which epilepsy develops. Among the several signaling pathways involved in epileptogenesis, this review discusses the roles of the Src family of tyrosine kinases (SFK), especially Fyn kinase, and inducible nitric oxide synthase (iNOS) mediated mechanisms. Both signaling molecules are upregulated following initial seizures and persist for a long time, contributing to neuroinflammation, elevated levels of reactive oxygen and nitrogen species (ROS/RNS), and proinflammatory cytokines, as well as neurodegeneration and spontaneously recurring seizures. Epilepsy is a progressive disease associated with unprovoked seizures and cognitive decline. While the current standard of care can alleviate symptoms and reduce mortality, they do not address long-term neurological consequences. In this review, we discuss preclinical testing of two CNS-targeted drugs, iNOS and SFK inhibitors 1400W and Saracatinib (SAR; AZD0530), respectively, as potential disease-modifiers.