Abstract:
Despite advances in neurobiology and the development of new antiepileptic drugs (AEDs) over the recent decades, available evidence indicate that the efficacy of drug treatment of epilepsy has not substantially improved. So the search for new antiepileptic drugs from natural compounds is imperative. This study aimed at providing supportive evidence for the folkloric use of Sphenocentrumjollyanum roots in the management of convulsions.
In this study dried, pulverized roots of Sphenocentrumjollyanum were extracted with a mixture of dichloromethane and methanol (1:1) using standard procedures to obtain Sphenocentrumjollyanum extract (SJE). The SJE was fractionated using chromatographic techniques to obtain the hexane fraction (HF), ethylacetate fraction (EF), and methanol fraction (MF). Anticonvulsant effects of SJE and the fractions were performed using strychnine- (STN), picrotoxin- (PTX) and pentylenetetrazole- (PTZ) induced seizure models in mice. Also, acute toxicity studies were performed using Lorke’s method.
The results showed that SJE significantly (p<0.05) delayed the onset of myoclonic spasms and tonic-clonic phases of seizures induced by STN, PTX, and PTZ. The percentage protection in all three seizure models was remarkable with SJE. At doses of 100, 200, and 400 mg/kg of SJE, the percentage protection against STN induced death was 100%, 80%, and 20% respectively. For PTX it was 60%, 80%, and 80% respectively, while for PTZ it was 60%, 80% and 80% respectively. However, the fractions (EF, HF, and MF) showed variable none dose-dependent effectiveness against the three chemoconvulsant models (STN: HF< EF < MF, PTX: MF < HF < EF, PTZ: HF<MF < EF), with the EF being the most effective fraction across each of the three seizure models, while the MF produced the highest delay in onset of myoclonic and tonic-clonic seizures cumulatively. The phytochemical analysis indicates the unique presence of terpenoidsamongs other phytoconstituents present, suggesting their role in the anticonvulsant effects of S. jollyanum roots. The LD50 for SJE was> 5000 mg/kg indicating that SJE is compatible with the chronic administration required in the treatment of epileptic seizures.
The results of the study suggest that Sphenocentrumjollyanum roots possesses anticonvulsant activity against seizure models in mice, thus validating the folkloric claims of the use of Sphenocentrumjollyanum root preparation in the treatment of convulsions. Further studies are needed to isolate the active compound responsible for this activity and to establish the possible mechanisms of action.
