Antiepileptic potential of flavonoids fraction from the leaves of Anisomeles malabarica

Ethnopharmacological relevance: The plant Chodara (Anisomeles malabarica R.Br. Family: Lamiaceae) has numerous therapeutic utilities in folk medicine. Aim of the study: To isolate and evaluate the anti-epileptic potential of fractions from the ethyl acetate extract (EAE) of Anisomeles malabarica leaves. Materials and methods: The EA extract (2.12% w/w) of the leaves of Anisomeles malabarica was prepared and fractionated into total flavonoids fraction (AMFF) and tannins fraction (AMTF), which subsequently evaluated for the antiepileptic activity against PTZ- and MES model in wistar rats. Diazepam and phenytoin (2 mg/kg and 25 mg/kg, i.p., respectively), were used as a reference drugs. Further, the presence of flavonoid was confirmed by chemical test, TLC and HPTLC were done for the identification of the number of flavonoids with reference to standard. Results: Single dose pretreatment with AMFF (25 and 50 mg/kg, i.p.) has found to be effective against both MES and PTZ-convulsions, but associated with a marked decrease in locomotor activity and motor activity performance (i.e., neurotoxic effects), similar to that of diazepam treatment. Interestingly, chronic treatment with AMFF at lower doses (6.25 and 12.5 mg/kg, i.p., 1 week) has also produced significant antiepileptic activity, but without causing neurotoxic effects. Conclusion: Thus, it may be concluded that the flavonoids fraction of the EA extract of Anisomeles malabarica leaves has antiepileptic potential against both MES and VIZ convulsion models. Acute treatment (25 and 50 mg/kg, i.p.) is associated with neurotoxic activity. Whereas, chronic treatment (6.25 and 12.5 mg/kg, i.p., 1 week) also shown significant antiepileptic effect without causing neurotoxic side effects. However, further research is in progress to determine the component(s) of the flavonoids fraction of Anisomeles malabarica involved and their mechanism of action in bringing about the desirable anti-epileptic effect. (C) 2011 Elsevier Ireland Ltd. All rights reserved.