Methanol leaf extract of Cusonea aborea Hochst (Araliaceae) possesses anticonvulsant activity in laboratory animals

Abstract

Cusonea aborea is used in the treatment of both infectious and  non-infectious diseases. The objective of this study was to investigate the anticonvulsant activity of methanol leaf extract of the plant in experimental animals. Phytochemical screening and acute toxicity studies were conducted. The anticonvulsant activity of the extract at doses of 75, 150, 300 and 600 mg/kg was evaluated in chicks (using maximal electroshock test) and mice (using pentylenetetrazole, 4-aminopyridine, strychnine, picrotoxin and isoniazid-induced) seizures models. Phytochemical screening revealed the presence of alkaloids, flavonoids, cardiac glycosides, saponins, tannins, streroids, anthraquinones and  triterpines. Intraperitoneal median lethal dose was estimated to be 2000 and 3800 mg/kg in mice and chicks respectively. The extract offered 40 % protection at 150, 300 and  600 mg/kg against maximal electroshock test. Protection of 50 and 33.33 % was offered at 75 and 150 mg/kg respectively against pentylenetetrazole-induced seizures. At 300 mg/kg, the extract confered 66.67 % protection and significantly (p<0.05) increased the onet of seizures in 4-aminopyridine test. Protection of 83.33 % and significant increase (p<0.05)  in the onset of seizure was seen at 300 mg/kg in strychnine-induced seizures. There was significant (p<0.05) increase in the onset of seizures at 300 mg/kg against picritoxin-induced seizures. No protection was offered by the extract against isoniazid-induced seizures at all of the tested doses. The findings revealed that the methanol leaf extract of Cusonea aborea possesses anticonvulsant activity and this may provide scientific basis for the use of the plant in the treatment of epilepsy.