Curcumin’s antiepileptic effect, and alterations in Nav1.1 and Nav1.6 expression in iron-induced epilepsy

Abstract

The present study was carried out to evaluate: the antiepileptic effect of dietary curcumin, and the effect of epileptic state and curcumin on the molecular expression of voltage-activated Na+ channel subtypes Nav1.1 and Nav1.6 in the iron-induced experimental epilepsy in the rat. Rats were divided into four groups; Group I (control rats), Group II (epileptic rats), Group III (curcumin-fed epileptic rats), and Group IV (curcumin-fed rats). Curcumin was fed chronically to rats approximately at the dose of 100 mg/kg body wt. The animals were made epileptic by intracortical injection of FeCl3. The mRNA and protein expressions of Nav1.1 and Nav1.6 were examined by RT-PCR analysis and immuno-histochemistry. Results showed a significant increase (upregulation) in the expression of both Nav1.1 and Nav1.6 with seizure activity in the cortex and hippocampus of epileptic rats. Epileptic rats fed with curcumin showed a marked decrease in epileptiform activity, and reduced mRNA and protein levels of Nav1.1. It appears that the antiepileptic action of curcumin may be associated with the downregulation of Nav1.1 in the cortex.