An aqueous extract of Lantana camara attenuates seizures, memory impairment, and anxiety in kainate-treated mice: Evidence of GABA level, oxidative stress, immune and neuronal loss modulation.

BACKGROUND: Epilepsy is a neurological disorder characterized by spontaneous recurrent seizures. Lantana camara (Verbenaceae) is a plant used in Cameroonian traditional medicine to treat dementia, epilepsy, and sleeping disorders. Hence, this study aimed to assess the antiepileptic-like effects of an aqueous extract of L. camara leaves on seizures induced by kainate in mice, and possible mechanisms of action. METHODS: Mice were divided into two groups: a normal control group treated with 0.9% saline (10 ml/kg, i.p.), and a kainate group treated with kainate (10 mg/kg, i.p.). All mice that developed status epilepticus were individually observed for spontaneous seizures. Eighteen days after the induction of status epilepticus, mice that exhibited spontaneous seizures were further divided into 6 groups of 7 mice each and treated as follows: a kainate group treated with 0.9% saline (10 ml/kg, p.o.), two positive control groups either treated with sodium valproate (300 mg/kg, p.o.) or with piracetam (200 mg/kg, p.o.), and three test groups received the extract (230, 460, and 917 mg/kg, p.o.). The control group was treated with 0.9% saline (10 ml/kg, p.o.). These treatments lasted 14 days and the animals were observed 6 h per day for behavioral seizures. Subsequently, the animals were evaluated for anxiety disorders and memory impairment. Animals were then sacrificed and the hippocampus or prefrontal cortex was collected for histological and biochemical analyses. Furthermore, the dilacerates of the hippocampi were stored for white blood cell count. RESULTS: The aqueous extract of L. camara (460 mg/kg) remarkably decreased (p < 0.001) the number and duration of seizures compared to sodium valproate. Also, it significantly increased the level of GABA both in the hippocampus and prefrontal cortex and protected these organs from oxidative stress. Furthermore, the extract (230 mg/kg) induced the highest reduction in the number of white blood cells in the hippocampus. Finally, the extract (917 mg/kg) significantly attenuated neuronal loss in the CA1, CA2, and CA3 regions of the hippocampus. All these compared to the negative control. CONCLUSION: These results suggest that the aqueous extract of L. camara has an antiepileptic-like effect comparable to that of sodium valproate. This, therefore, warrants further investigation into the effect of bioactive molecules present in the extract using in vitro and in vivo models of epilepsy.

An aqueous extract of Canarium schweinfurthii attenuates seizures and potentiates sleep in mice: Evidence for involvement of GABA Pathway.

About 30% of epileptic patients continue to have seizures. The present study investigates the anticonvulsant and sedative effects of an aqueous extract of C. schweinfurthii in mice. Anticonvulsant effects of C. schweinfurthii aqueous extract (0.01-300 mg/kg, p.o.) were tested against 4-aminopyridine (4-AP, 15 mg/kg, i.p.) -, pilocarpine (PILO, 380 mg/kg, i.p.) - and pentylenetetrazole (PTZ, 75 mg/kg, i.p.) -induced seizures, while sedative effects were tested on diazepam (35 mg/kg, i.p.)-induced sleep. Afterward, the most effective dose of the extract (11.9 mg/kg) was antagonized with N-methyl-ß-carboline-3-carboxamide or flumazenil. In another set of experiments, mice were sacrificed for the estimation of GABA content and GABA-T activity in the cerebral cortex. The dose of the extract that protected 50% of mice (ED50) against 4-AP, PILO, and PTZ was respectively 4.43 mg/kg (versus 12.01 for phenobarbital), 9.59 mg/kg (vs 8.67 for diazepam), and 2.12 mg/kg (vs 0.20 for clonazepam). Further, the ED50 of the extract that increased the duration of sleep was 0.24 mg/kg (vs 0.84 for phenobarbital). N-methyl-ß-carboline-3-carboxamide or flumazenil antagonized (p < 0.001) the anticonvulsant effect of C. schweinfurthii in PTZ-induced seizures and diazepam-induced sleep when compared to the negative control group. The extract at all doses increased (p < 0.001) the GABA content and decreased (p < 0.001) GABA-T activity. These findings suggest that C. schweinfurthii possesses anticonvulsant and sedative effects. These effects seem to be mediated via the modulation of the GABA neurotransmission. These data explain the use of this plant to treat epilepsy in Cameroon traditional medicine.