Justicia spicigera Schltdl. and kaempferitrin as potential anticonvulsant natural products

Justicia spicigera Schltdl. is a vegetal species traditionally used to control epilepsy, but scientific evidence is required to reinforce this activity. The aim of the study was to evaluate the anticonvulsant-like activity of J. spicigera aqueous extract (JsAE) and a bioactive compound. JsAE was assessed in a dose-response manner (30, 100 and 1000 mg/kg, i.p.) using the pentylenetetrazol (PTZ)-induced seizures and maximal electroshock seizure (MES) test in mice in comparison to ethosuximide (ETX, reference drug 100 mg/kg, i.p.) or phenytoin (25 mg/kg, i.p.), respectively. Then a significant dosage (1000 mg/kg, i.p.) was chosen to examine electrographic activity (EEG) in rats. Treatment groups were compared to the vehicle and ETX in the convulsive behavior alone or simultaneous to EEG after PTZ-induced seizures (80 or 35 mg/kg, i.p., mice or rats). Kaempferitrin (a flavonoid of JsAE) and ETX were administered via intracerebroventricular (i.c.v, 4th ventricle, 1 μg/μL) and tested in the presence of PTZ in rats. Results confirmed that JsAE delayed the onset of seizures and reduced frequency of tonic convulsion and mortality in mice. JsAE or kaempferitrin also decreased the EEG spikes frequency and amplitude in a similar manner than EXT in rats. In conclusion, these preliminary data give evidence of the potential of J. spicigera as possible anticonvulsant as recommended in folk medicine for treating epilepsy, where kaempferitrin is suggested as a partial responsible bioactive compound.