Alterations in the Glutamate metabolism and Aminotransferases (AAT, ALAT) during PTZ – induced Epilepsy: Protective role of Bacopa monnieri

Alterations in the Glutamate metabolism and Aminotransferases (AAT, ALAT) during PTZ – induced Epilepsy: Protective role of Bacopa monnieri

E. Komali, Ch. Venkataramaiah and W. Rajendra*

Division of Molecular Biology, Department of Zoology, Sri Venkateswara University- Tirupati

Epilepsy, a common chronic neurological disorder characterized by repeated, spontaneous seizures, also known as seizure disorder. Seizure related neuronal injury has been assumed to be mediated by glutamate, the excitatory amino acid, in the central nervous system that causes a sudden imbalance between the inhibitory and excitatory signals in the brain with glutamate, γ-aminobutyric acid (GABA), noradrenaline, serotonin, and dopamine. Since long term usage of antiepileptic drugs cause high incidence of pharmacoresistence and untoward side effects, attention has been paid in recent years to screen bioactive compounds from natural medicinal plants for treatment of several neurological disorders including Epilepsy. Keeping in view of relative importance of natural medicinal plants, the present study is mainly focused to characterize the anti-convulsant effect of Bacopa monnieri (BM), an Indian herb which is being extensively used in Ayurvedic treatments related to neurological complications. The present study is designed to assess the neurotoxicity of Pentylene tetrazole (PTZ), an epileptic compounds, on the Glutamate metabolism and Amino transferases in different brain regions (Cerebral cortex, Cerebellum, Pons medulla and Hippocampus) of rat and to explore the possible antiepileptic effect of different extracts (Ethanol, n-Hexane, Chloroform, Ethyl acetate, n-Butanol and Aqueous extracts) of BM in comparison with Diazepam (DZ) (Reference control).  The activities of glutamate dehydrogenase (GDH), glutamine synthetase (GS) and glutamine content were decreased in different regions of brain during PTZ induced epilepsy which were increased in epileptic rats pretreated with different extracts of Bacopa monnieri except EAE and AE. Glutaminase activity was increased in PTZ induced epilepsy and decreased on pretreatment with all the extracts of BM except AE. In addition aspartate (AAT) and alanine aminotransferase (ALAT) activity levels were increased during PTZ induced epilepsy when compared with normal control and levels were reversed on pretreatment with different extracts of BM. Recoveries of these parameters during antiepileptic treatment suggest that the bioactive factors present in the extracts offer neuroprotection by interrupting the pathological cascade of glutamatergic hyperexcitation that occurs during epileptogenesis.

Keywords:  Epilepsy, Bacopa monnieri, Pentylene tetrazole, Glutamate metabolism, AAT (Aspartate aminotransferase), ALAT (Alanine aminotransferase).

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E. Komali, Ch. Venkataramaiah and W. Rajendra. Alterations in the Glutamate metabolism and Aminotransferases (AAT, ALAT) during PTZ – induced Epilepsy: Protective role of Bacopa monnieri. Journal of Herbal Medicine Research, 2017, 2:20. DOI: 10.28933/JHMR-2017-11-2001


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