• Biomolecules & Therapeutics
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• v.28 no.2
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• pp.137-144
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• 2020

Epilepsy is a brain disorder that affects millions of people worldwide and is usually managed using currently available antiepileptic drugs, which result in adverse effects and are ineffective in approximately 20-25% of patients. Thus, there is growing interest in the development of new antiepileptic drugs with fewer side effects. In a previous study, we showed that a Rehmannia glutinosa (RG) water extract has protective effects against electroshock- and pentylenetetrazol (PTZ)-induced seizures, with fewer side effects. In this study, the objective was to identify the RG components that are responsible for its anticonvulsant effects. Initially, a number of RG components (aucubin, acteoside, catalpol, and mannitol) were screened, and the anticonvulsant effects of different doses of catalpol, mannitol, and their combination on electroshock- and chemically (PTZ or strychnine)-induced seizures in mice, were further assessed. Gamma-aminobutyric acid (GABA) receptor binding assay and electroencephalography (EEG) analysis were conducted to identify the potential underlying drug mechanism. Additionally, treated mice were tested using open-field and rotarod tests. Catalpol, mannitol, and their combination increased threshold against electroshock-induced seizures, and decreased the percentage of seizure responses induced by PTZ, a GABA antagonist. GABA receptor binding assay results revealed that catalpol and mannitol are associated with GABA receptor activity, and EEG analysis provided evidence that catalpol and mannitol have anticonvulsant effects against PTZ-induced seizures. In summary, our results indicate that catalpol and mannitol have anticonvulsant properties, and may mediate the protective effects of RG against seizures.

• Journal of Applied Biological Chemistry
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• v.48 no.1
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• pp.32-34
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• 2005

Arils of Euporia longana L. was extracted with 80% aqueous MeOH and partitioned successively with EtOAc, n-BuOH and $H_2O$. From the n-BuOH fraction, furan compound was isolated through silica gel column chromatography. The results of physico-chemical data including NMR, MS and IR revealed the compound to be 5-(hydroxymethyl)-2-furfuraldehyde. This compound stimulated GDH I activity by $19.2{\pm}0.6$, $41.2{\pm}0.9$, $68.4{\pm}1.1$, $80.3{\pm}0.9$ and $85.9{\pm}1.6%$ at in vitro concentrations of 0.005, 0.008, 0.02 and 0.03 %, respectively.

• Korean Journal of Pharmacognosy
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• v.30 no.3
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• pp.284-289
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• 1999

In order to find active ingradients having an agonistic activity to benzodiazepine receptor from Gastrodia elata Blume (Orchidaceae) which has been used as an anticonvulsant in oriental medicine, one component and some fractions were separated from the butanol extract of the rhizomes of this plant and evaluated for their activities on GABA/benzodiazepine receptor in vitro. As a result, one crude mixture (F4f) obtained from the most active fraction (F4) inhibited significantly the binding of $[^3H]Ro15-1788$, a selective benzodiazepine receptor antagonist, to benzodiazepine receptor of rat cortices. GABA significantly enhanced the inhibition of $[^3H]flunitrazepam$ binding by F4f, and this positive GABA shift supported the strong possibility of the agonistic activity of F4f to benzodiazepine receptor.

• The Journal of Korean Medicine
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• v.23 no.3
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• pp.211-222
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• 2002

Currently convulsion is considered to be a chronic central nerve disease characterized by involuntary and severe muscle contraction or spasm. In many recent studies, convulsion's mechanism is due to unbalance between stimulation and suppression of the central nerve system, such as GABA and glutamic acid. Objectives : This study was performed to examine the anticonvulsant effects of Podam-hwan on brain GABA levels and glutamate content in picrotoxin-induced convulsions and to determine the inhibitory activity on GABA transaminase. Methods : Brain GABA levels and glutamate content in the brains of picrotoxin-induced mice using reverse phase HPLC method, anticonvulsant effect in vivo, and the inhibitory effect on GABA transaminase activity in vivo have been investigated. Results : Podam-hwan significantly lengthened the onset time of picrotoxin-induced convulsion at a concentration of 15mg/kg, but did not show a dose-dependent pattern. Also, Podam-hwan shortened the duration of convulsion by 52.2% at a dose of 30mg/kg in comparison with the control group. Podam-hwan inhibited dose-dependently GABA transaminase activity by 35.5% at 30mg/kg, comparing with the control gmup. Podam-hwan also increased the brain GABA level by 38.7% and 68.8% at doses 15mg/kg and 30mg/kg, respectively. In addition, Podam-hwan decreased the brain glutamate level by 9.6% and 17.8% at doses 15mg/kg and 30mg/kg, respectively. Conclusions : Podam-hwan can be prescribed for the treatment of convulsion by enhancement of brain GABA level and inhibition of GABA transaminase activity.

• Bulletin of the Korean Chemical Society
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• v.26 no.11
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• pp.1757-1760
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• 2005

A series of 6-alkyloxyl-3,4-dihydro-2(1H)-quinoliones (5a-5n) were synthesized through nitration, reduction, diazotization, hydrolysis and alkylation from 3,4-dihydro-2(1H)-quinolione. Their structures were characterized by IR, $^1H$-NMR and MS. The anticonvulsant activity was evaluated by the Maximal electroshock test (MES) and the subcutaneous pentylenetetrazole (Metrazole) test (sc-Met). The neurotoxicity was measured by the Rotarod test (Tox). The result showed that 6-hexyloxy-3,4-dihydro-2 (1H)-quinolinone (5c) was potent in anti-MES and anti-scMet test with $ED_{50}$ of 24.0 mg/kg and 21.2 mg/kg, respectively, albeit its $TD_{50}$ (67.6 mg/kg) revealed the high neurotoxicity. 6-Benzyloxy-3,4-dihydro-2(1H)-quinolinone (5f) was less effective against MES induced seizure with $ED_{50}$ of 29.6 mg/kg, but no neurotoxicity was observed even under 300 mg/kg. Its Protective index (PI) was greater than 10 preferable to Phenytoin, Carbamazepin, Phenobarbital and Valproate.

• Archives of Pharmacal Research
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• v.29 no.12
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• pp.1080-1085
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• 2006

A series of 8-alkoxy-4,5-dihydro-[1,2,4]triazole[4,3-a]quinoline-1-one derivatives were synthesized using 7-hydroxy-3,4-dihydro-2(1H)-quinolone as the starting material. Their anticonvulsant activities were evaluated by the maximal electroshock test (MES) and the subcutaneous pentylenetetrazole test (sc-PTZ), and their neurotoxicities were measured by the rotarod neurotoxicity test (Tox). The tests demonstrated that 8-hexyloxy-4,5-dihydro-[1.2.4]triazole[4.3-a]quinoline-1-one (4e) and 8-heptyloxy-4,5-dihydro-[1,2,4]triazole[4, 3-a]quinoline-1-one (4f) were the most potent anticonvulsants, with 4e having $ED_{50}$ values of 17.17 mg/kg and 24.55 mg/kg and protective index ($PI=TD_{50}/ED_{50}$) values of 41.9 and 29.3 in the MES and sc-PTZ tests, respectively, and 4f having $ED_{50}$ values of 19.7 mg/kg and 21.2 mg/kg and PI values of 36.5 and 33.9 in the MES and sc-PTZ tests, respectively. The PI values of 4e and 4f were many fold better than that of the marketed drugs phenytoin, carbamazepine, phenobarbital and valproate, which have PI values in the range of 1.6-8.1 in the MES test and <0.22-5.2 in the sc-PTZ test. Structure-activity relationships were also discussed.

• Journal of Oriental Neuropsychiatry
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• v.17 no.3
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• pp.21-43
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• 2006

This study was designed to assess Effects of jingansikpungtanggagam-bang on Central Nerve System. Method : jingansikpungtanggagam-bang, a Korean traditional prescription, was evaluated for its anticonvulsant effect, hypnotic activity, analgesic action, anxiolytic effect, memory enhancement, and MAO inhibitory activity and detennined the content of neurotransmitter in brain by HPLC method. Result : 1. The extract increased potently anticonvulsant effect at 1g/kg by 5.6-fold extention of onset time against control group. 2. The extract increased hvrmsis at 500mg/kg by over twofold length of sleeping time compared to control. 3. The extract showed a significant analgesic effect with 86.0% inhibition on writhing frequency at 500mg/kg by phenylquinone-induced writhing test. 4. The extract inhibited dose-dependently the activity of monoamine oxidase in vitro. 5. This prescription increased the brain levels of serotonin and 5-hydroxyindoleacetic acid by 3.3% and 1.4%, respectively. 6. the extract exhibited the anxiolytic effect with 21.3% decrease of the immobility duration against control group. 7. the extract enhanced memory recovery on scopolamine-induced impairment of passive avoidance performance at 1g/kg pretreatment with 20.2% increase of latency time. Conclusion : The result sugguest that jiugansikpungtanggagam-bang can be used effectively as a sedative prescription in Korean traditional medicine.

• Journal of Life Science
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• v.12 no.5
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• pp.505-514
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• 2002

The aim of this study was to evaluate the anticonvulsant activity of four agents derived from tropinone (T-1: 2,4-dipyrrolylmethenylnortropinone, T-2: 2,4-diphenylmethenylnortropinone, T-3 : 2,4-difurfurylmethenylnortropinone, T-4 : 2,4-dimethoxyphenylmethenylnortropinone) in NIH Swiss mouse. Pentylenetetrazole (nZ) was injected via intraperi-toniurn in mouse and Maximal Electroshock (MES) stimulation was through both conjunctivas by electrodes. Tropinone derivatives were treated at 15 minutes before PTZ or MES procedure. PIZ of 25 mg/kg induced generalized seizure in mouse, effects of tropinone derivatives on PTZ-induced seizure were monitored. Compared with control group, T-4 decreased seizure grade most effectively. Also T-4 increased onset time of PTZ-induced seizure. This result showed that T-4 is most effective on PTZ-induced seizure. In MES-induced seizure, T-1 decreased seizure grade and recovery time. nNOS expression in hippocampus and cortex were increased in nZ- and MES-induced seizure animals compared with control. Pretreatment of tropinone derivatives in PTZ-induced seizure did not affected nNOS expression in brain tissues, but T-1 and T-4 decreased nNOS expression in cortex of MES-induced seizure animals. These findings suggest that tropinone derivatives have specific anticonvulsant activities according to PTZ- and MES-induced seizure. 2,4- dimethoxyphenylmethenylnoroopinone is most effective in PTZ-induced seizure and 2,4-di methoxyphenylmethenylnortropinone is most effective in MES-induced seizure.

• Applied Biological Chemistry
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• v.43 no.1
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• pp.72-77
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• 2000

The repeated silica gel colum chromatographies of EtOAc fraction, showing anticonvulsant activity, obtained from MeOH extracts of Schizandra chinensis B. fruits led to isolation of a sesquiterpenoid, four lignans and a sterol glycoside. Their chemical structures were determined to be chamigrenal, gomisin A, gomisin H, gomisin N. schizandrin and daucosterol. Among them, schizandrin and daucosterol inhibited GABA degrative enzymes, succinic semialdehyde dehydrogenase and succinic semialdehyde reductase, respectively. It is postulated that the schizandrin and daucosterol are able to elevate the neurotransmitter GABA levels in central nervous system by inhibitory action on GABA degrative enzymes and act as anticonvulsant drugs.

• Natural Product Sciences
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• v.12 no.1
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• pp.44-49
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• 2006

The aqueous extract of Hydrilla verticillata (AEHV) was tested for possible pharmacological effects on experimental animals. AEHV significantly potentiated the sleeping time of mice induced by standard hypnotics viz. pentobarbitone sodium, diazepam, and meprobamate in a dose dependent manner. AEHV showed significant analgesic properties as evidenced by the significant reduction in the number of writhes and stretches induced in mice by 1.2% acetic acid solution. It also potentiated analgesia induced by morphine and pethidine in mice. Pretreatment with AEHV caused significant protection against strychnine and leptazol-induced convulsions. The behavioral studies on mice indicate CNS depressant activity of the aqueous extract of H. verticillata.