Deralakatte, Mangalore, India Dept of Pharmacology, Yenepoya Medical College, Yenepoya University,

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1 International Journal of Universal Pharmacy and Bio Sciences 2(3): May-June 2013 INTERNATIONAL JOURNAL OF UNIVERSAL PHARMACY AND BIO SCIENCES Pharmaceutical Sciences Research Article!!! Received: ; Accepted: ANTICONVULSANT ACTIVITY OF HYRDROETHANOLIC EXTRACT OF VALERIANA WALLICHII ROOT ON MAXIMAL ELECTROSHOCK INDUCED SEIZURE MODEL IN SWISS ALBINO MICE Lovelyn Joseph 1*, Rao Sudarshanram Narayan 2 1 Dept of Pharmacology, Yenepoya Medical College, Yenepoya University, Deralakatte, Mangalore, India Dept of Pharmacology, Yenepoya Medical College, Yenepoya University, Deralakatte, Mangalore, India KEYWORDS: ABSTRACT Epilepsy is one of the most common serious disorders of the brain, Anticonvulsant, Maximal Electroshock Seizures, affecting about 50 million people worldwide. Epilepsy accounts for 1% of the global burden of disease; 80% of the burden of epilepsy is in the developing world, where in some areas 80 90% of people with Valeriana Wallichii. epilepsy receive no treatment at all. Valeriana wallichii For Correspondence: Lovelyn Joseph * Address: Dept. of (Valerianaceae) is an indigenous medicinal and aromatic plant of Himalayan region and that is widely exploited for its roots and rhizomes which contain valepotriates and valerinic acids (with putative pharmacological activities). It is used as ethno medicine for the treatment of habitual constipation, insomnia, epilepsy, neurosis, Pharmacology, Yenepoya anxiety, diuretic, hepatoprotective, analgesic and cytotoxic, Medical College, Yenepoya University, Deralakatte, Mangalore, India antispasmodic, anticonvulsant, nematicidal, anti inflammatory, etc. Hydroethanolic extract of Valeriana wallichii root was administered orally at 200, 400, 600 mg/kg body weight and screened for anticonvulsant activity against maximal electroshock seizures induced convulsions after an hour in comparison with Phenytoin (standard) and saline (control) treated groups.. Effects of the extract on motor co ordination were tested with Rota rod test before dosing and 45 minutes post dosing Valeriana wallichii root hydroethanolic extract showed a dose dependant reduction of hind limb tonic extensor phase in comparison with standard and control groups which was statistically significant, indicating potential antiepileptic effect on grand mal type of epilepsy in man. The extract didn t show any adverse effects on motor coordination. Further investigations are required to identify the active constituents responsible for anticonvulsant activity and their mechanism(s) of action. 065

2 INTRODUCTION: The term epilepsy refers to a disorder of brain function characterized by the periodic and unpredictable occurrence of seizures [3]. Seizures are transient alteration of behavior due to the disordered, synchronous, and rhythmic firing of populations of brain neurons [4]. Seizures can be "non epileptic" when evoked in a normal brain by treatments such as electroshock or chemical convulsant and "epileptic" when occurring without evident provocation [4, 5]. Many drugs have been successfully used in treating epilepsy but still treatment resistant cases and severe adverse effects especially in long term use (which is required in majority of the cases) are major shortcomings. Therefore there is a need for better drugs and treatment strategies. Reverse pharmacology and ethno pharmacology are two research areas for discovery of new therapeutic strategies and drug candidates. Valeriana wallichii (Vw) is a rhizome herb of the genus Valeriana and belongs to the family Valerianaceae also called Indian Valerian or Tagar. Valeriana wallichi is mainly grown in the north western Himalaya, Uttaranchal and Nepal [6]. The Indian Valerian is used as ethno medicine for the treatment of habitual constipation, insomnia, epilepsy, neurosis, anxiety, diuretic, hepatoprotective, analgesic and cytotoxic, antispasmodic, anticonvulsant, nematicidal, anti inflammatory, etc [2]. The present study was designed to investigate the anticonvulsant activity of the Hydro-Ethanolic root extract of Vw with Maximal electroshock seizure test (electrical stimulation induced convulsions by using Electro-Convulsiometer) in Swiss albino mice. Maximal electroshock seizure would be mimicking generalized tonic clonic seizures (GTC/ Grandmal type of epilepsy in humans), and is a standard screening method for detecting and evaluating antiepileptic activity [7]. MATERIALS AND METHODS Plant Materials The roots of Valeriana Wallichii was procured from M.Subhash Chand And Sons, Karyana Merchants, Himachal Pradesh and authenticated the botanical name of the plant as Valeriana wallichii DC (Family :Valerianaceae) by Dr.Radhakrishna Rao, Alvas Ayurvedic Medical College, Mangalore, Karnataka. Valeriana wallichii root hydro ethanolic extract (VRHE) preparation The VW root was shade dried and exposed to exhaustive extraction using soxhlet apparatus using distilled water and ethanol (10:90) as solvent system. After drying on a water bath at 50 0 c, yield of the Hyrdroethanolic extract was 25.3%. Experimental animals: The experimental protocol was approved by the Institutional Animal Ethical Committee (IAEC), Yenepoya University and care of laboratory animals were taken as per CPCSEA 066

3 guidelines. Animals were housed (Animal house, Yenepoya University, Reg.no 347/CPCSEA) in polypropylene cages; uniform temperature (25 ±2º C) and light and dark cycle (light period, ) were maintained in a controlled room with relative humidity of 50 55%. Food and water were provided ad libitum. Experiments were carried out between 15:00 to 19:00 hrs. Experimental design 30 Swiss albino mice were divided in to 5groupes, 6 animals per group (male and female in equal ratio). Group1- Control (normal saline 0.1ml/10g body weight/ oral) Group2- Positive control (Phenytoin 25mg/kg body weight, ip) Group3- VRHE 200mg/kg body weight, oral route Group4- VRHE 400mg/kg body weight, oral route Group5- VRHE 600mg/kg body weight, oral route In this experiment 3-4 months old Swiss albino mice were used, randomly divided into five groups and test drug was administered one hour prior to the seizure induction. Experimental procedures: To screen Anticonvulsant activity Maximal electroshock seizure test Maximal electroshock seizures test is performed with 0.2-second series alternating current with 50Hz frequency and an intensity of 48 m 0 A in mice applied through ear electrode primed with an electrolyte solution. Suppression of tonic hind limb extension was taken as a measure of efficacy in this test. To screen neurotoxicity-rota rod test The Rota rod test is used to assess motor coordination and balance in rodents. Mice have to keep their balance on a rotating rod. The time (latency) it takes the mouse to fall off the rotating rod is measured. Motor coordination was tested by comparing the latency to fall on the very first trial between treatment groups [8, 9] at 6 rpm. Rota rod test was conducted before and after 45minutes of dosing, 120 sec was kept as the end point. If mice treated with extract meet the end point, the extract was considered to be free of toxic effects on motor coordination. All the mice had to pass Rota rod test as an inclusion criterion (prior to the test). RESULTS 1. Maximal electroshock seizure test: The extract reduced duration of HLTE in a dose dependant manner (Fig 1). One-way Analysis of Variance (ANOVA) was conducted and P value was < 0.001considered extremely significant. i.e., Variation among column means is significantly greater than expected by chance. Dunnett Multiple Comparisons Test compared the mean difference and p value was < 0.01 indicating significant difference in HLTE duration of treated groups compared to control group. 067

4 Fig 1: Duration of Maximal electroshock induced Hind Limb Tonic Extensor Phase (in Seconds) in mice Mean and Standard Deviation A B C D E Phenytoin Column 200mg/kg 400mg/kg 600mg/kg 25mg/kg Control 2. Rota rod test for motor side effects: All the animals passed Rota rod test indicating no motor adverse effect for the extract at given dose range. 3. Another important observation was dose dependant reduction in percentage of mortality in extract treated groups (200mg/kg - 50%, 400mg/kg 0%, 600mg/kg 0% compared with 0% in Phenytoin treated group and 66.66% in control group (Fig 2). Fig 2: percentage of post MES mortality in mice Mean and Standard Error A B C D E Phenytoin Column 200mg/kg 400mg/kg 600mg/kg 25mg/kg Control 068

5 DISCUSSION The Maximal electroshock seizure identifies those compounds which prevent seizure spread. Abolition of the hind limb tonic extensor (HLTE) component (Fig 1) indicates the test compound's ability to inhibit MES-induced seizure spread [10, 11, 12]. The model is highly reproducible with consistent endpoints. The behavioral and electrographic seizures generated in this model are consistent with the human disorder 14. Therefore since Valeriana wallichi root extract is showing protective effect against maximal electroshock induced seizures it indicates its usefulness in generalized tonic clonic seizures in humans. Moreover the extract was found to protect against the maximal electroshock induced mortality in a dose dependant manner similar to the positive control group. The extract didn t exhibit any adverse effect on motor co ordinance as seen from Rota rod test (Fig 2) which is adopted as a primary test for neurotoxicity by the Anticonvulsant Screening Program (ASP) [13], therefore the extract is devoid of any neurotoxicity according to this test at the given dose range. Phytochemical analysis of the extract to identify the active components in it and pharmacodynamic studies to discover the mechanisms of action are needed. Major phytochemicals in Valeriana wallichi are Valerian, Valipotriates and GABA [14]. More advanced studies to elucidate mechanism of action and to isolate active principles from the plant are indicated. The available valerian crude preparations marketed as sedative hypnotic neutraceuticals should undergo combination analysis with existing antiepileptic drugs to ascertain synergistic interactions if any, which may give rise synergistic combination therapy to reduce the adverse effect of the latter by reducing the required dose, and to treat treatment resistant cases but only if valerian crude extracts show synergism and a better adverse effect profile with the standard antiepileptic drugs. REFERENCES 1. Atlas: Epilepsy Care in the World, World Health Organization, Programme for 069 Neurological Diseases and Neuroscience Department of Mental Health and Substance Abuse, ISBN , Page no: Saklani Neha, Purohit VijayK., Andola Harish., Rana Mahendra, Chauhan R.S., Nautiya A. R. (2012), Biological activities of Valeriana wallichii DC Medicinal Plants - International Journal of Phytomedicines and Related Industries,Volume:4, Issue:3, page no: Laurence L. Brunton, John S. Lazo, Keith L. Parker. (2006), Goodman & Gilman s The Pharmacological Basis of Therapeutics. 11 th ed. New York: McGraw-Hill; p James OM. (2001), Drugs effective in the therapy of epilepsy. In: Joel GH, Lee EL, Alfred GG, editors. The pharmacological basis of therapeutics. 10th edition. New York: McGraw-Hill; pp

6 5. Clarke CRA. (1998), Neurological diseases. In: Parveen K, Michael C, editors. Clinical medicine. 4th edition. Edinburgh: W.B. Saunders; pp Chemical perspective of Tagar An Ayurvedic drug C S Mathela, C S Chanotiya, S Sati, M Tiwari & S S Sammal.(2006), Indian Journal of Traditional Knowledge Vol 5(4), pp James E. P. Toman, Ewart A. Swinyard and Louis S.Goodman, (1946), Seizures and their alteration by anticonvulsant drugs and other agents, J Neurophysiol 9: Lalonde, R., et al., (2003), Motor coordination in mice with hotfoot, Lurcher, and double mutations of the Grid2 gene encoding the delta-2 excitatory amino acid receptor. Physiol Behav, 80(2-3): p Buitrago, M.M., et al., (2004), Short and long-term motor skill learning in an accelerated rotarod training paradigm. Neurobiol Learn Mem, 81(3): p Swinyard, E.A., Woodhead, J.H., White, H.S. & Franklin, M.R. (1989): General principles: experimental selection, quantification, and evaluation ofanticonvulsants. In: Antiepileptic Drugs, Third Edition R.H. Levy, R.H. Mattson, B. Melrum, J.K. Penry and F.E. Dreifuss eds, pp New York: Raven Press. 11. White, H.S., Johnson, M., Wolf, H.H. & Kupferberg, H.J. (1995): The early identification of anticonvulsant activity: role of the maximal electroshock and subcutaneous pentylenetetrazol seizure models. Italian Journal of Science 16, White, H.S., Woodhead, J.H. & Franklin, M.R. (1995): General principles: experimental selection, quantification, and evaluation of antiepileptic drugs. In: Antiepileptic Drugs, Fourth Edition, eds. R.H. Levy, R.H. Mattson and B.S. Meldrum pp New York: Raven Press. 13. James P. Stables and Harvey J. Kupferberg, The NIH Anticonvulsant Drug Development (ADD) Program: preclinical anticonvulsant screening project, Chapter 16, Epilepsy Branch, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD 20892, USA. 14. Valerian root, analytical quality control and therapeutic monograph. April American herbal pharmacopoeia and therapeutic compendium. 15. William J. Giardina1 and Maciej Gasior, (2009), Acute Seizure Tests in Epilepsy Research: Electroshock- and Chemical-Induced Convulsions in the Mouse, Current Protocols in Pharmacology