Anticonvulsant Effects of Chrysanthellum americanum L. (Vatke) Aqueous Extract in Mice Pilocarpine Model of Epilepsy and Associated Memory Impairment: Role of Antioxidant Defense System and Cholinergic Transmission

Abstract

Chrysanthellum americanum (L.) Vatke is a medicinal plant used by the traditional healers to treat epilepsy and associated memory impairment. This work aims at evaluating the anticonvulsant effects of Chrysanthellum americanum aqueous extract in mice pilocarpine model of epilepsy and associated memory loss. Mice were administered orally Chrysanthellum americanum aqueous extract (27.69, 69.22, 138.45, 276.9 mg/kg, prepared from the whole part) for test groups, intraperitoneally 300 mg/kg sodium valproate for the positive control group or orally 10 mL/kg distilled water for the negative control group, respectively, during a period of seven consecutive days. On the first day, temporal lobe epilepsy was induced by intraperitoneal injection of 360 mg/kg pilocarpine one hour after the administration of different treatment to mice, and the occurrence of status epilepticus was evaluated. On the second day, the anticonvulsant property was measured after the intraperitoneal injection of a sub-convulsive dose of picrotoxin (1 mg/kg). On the seventh day, the anti-amnesic properties of the extract were evaluated in the epileptic mice using the T-maze and open field paradigms. The results show that Chrysanthellum americanum extract significantly (p < 0.01) increased the latency to clonic and generalized clonic-tonic convulsions, and decreased the number and duration of seizures. The plant extract induced a significant (p < 0.001) increase in the number of entries and time spent into preferred arm of the T-maze test. The number of crossing and the time spent in the centre of the open field were increased by the extract. Chrysanthellum americanum (276.9 mg/kg) likewise sodium valproate (300 mg/kg) significantly (p < 0.01) alleviated pilocarpine-induced increase in the hippocampal malondialdehyde and nitric oxide levels; increased the reduced glutathione and acetylcholine rates, and the activities of catalase and super oxide dismutase. In summary, these results indicate that Chrysanthellum americanum aqueous extract has anticonvulsant effects against pilocarpine induced-epileptic seizures and memory impairment. These properties could be mediated by the amelioration of antioxidant defense system and cholinergic neurotransmission in epileptic mice, which could partly justify the use of Chrysanthellum americanum in the traditional medicine for the treatment of epilepsy.